SemaDecl.cpp revision 235e0bb2f79c241e48480447301a7e0d19f9ccb8
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()) { 214 // There is already a declaration of a function on our 215 // IdResolver chain. Replace it with this declaration. 216 S->RemoveDecl(*Redecl); 217 IdResolver.RemoveDecl(*Redecl); 218 } 219 } 220 221 IdResolver.AddDecl(D); 222} 223 224void Sema::ActOnPopScope(SourceLocation Loc, Scope *S) { 225 if (S->decl_empty()) return; 226 assert((S->getFlags() & (Scope::DeclScope | Scope::TemplateParamScope)) && 227 "Scope shouldn't contain decls!"); 228 229 for (Scope::decl_iterator I = S->decl_begin(), E = S->decl_end(); 230 I != E; ++I) { 231 Decl *TmpD = static_cast<Decl*>(*I); 232 assert(TmpD && "This decl didn't get pushed??"); 233 234 assert(isa<NamedDecl>(TmpD) && "Decl isn't NamedDecl?"); 235 NamedDecl *D = cast<NamedDecl>(TmpD); 236 237 if (!D->getDeclName()) continue; 238 239 // Remove this name from our lexical scope. 240 IdResolver.RemoveDecl(D); 241 } 242} 243 244/// getObjCInterfaceDecl - Look up a for a class declaration in the scope. 245/// return 0 if one not found. 246ObjCInterfaceDecl *Sema::getObjCInterfaceDecl(IdentifierInfo *Id) { 247 // The third "scope" argument is 0 since we aren't enabling lazy built-in 248 // creation from this context. 249 NamedDecl *IDecl = LookupName(TUScope, Id, LookupOrdinaryName); 250 251 return dyn_cast_or_null<ObjCInterfaceDecl>(IDecl); 252} 253 254/// getNonFieldDeclScope - Retrieves the innermost scope, starting 255/// from S, where a non-field would be declared. This routine copes 256/// with the difference between C and C++ scoping rules in structs and 257/// unions. For example, the following code is well-formed in C but 258/// ill-formed in C++: 259/// @code 260/// struct S6 { 261/// enum { BAR } e; 262/// }; 263/// 264/// void test_S6() { 265/// struct S6 a; 266/// a.e = BAR; 267/// } 268/// @endcode 269/// For the declaration of BAR, this routine will return a different 270/// scope. The scope S will be the scope of the unnamed enumeration 271/// within S6. In C++, this routine will return the scope associated 272/// with S6, because the enumeration's scope is a transparent 273/// context but structures can contain non-field names. In C, this 274/// routine will return the translation unit scope, since the 275/// enumeration's scope is a transparent context and structures cannot 276/// contain non-field names. 277Scope *Sema::getNonFieldDeclScope(Scope *S) { 278 while (((S->getFlags() & Scope::DeclScope) == 0) || 279 (S->getEntity() && 280 ((DeclContext *)S->getEntity())->isTransparentContext()) || 281 (S->isClassScope() && !getLangOptions().CPlusPlus)) 282 S = S->getParent(); 283 return S; 284} 285 286void Sema::InitBuiltinVaListType() { 287 if (!Context.getBuiltinVaListType().isNull()) 288 return; 289 290 IdentifierInfo *VaIdent = &Context.Idents.get("__builtin_va_list"); 291 NamedDecl *VaDecl = LookupName(TUScope, VaIdent, LookupOrdinaryName); 292 TypedefDecl *VaTypedef = cast<TypedefDecl>(VaDecl); 293 Context.setBuiltinVaListType(Context.getTypedefType(VaTypedef)); 294} 295 296/// LazilyCreateBuiltin - The specified Builtin-ID was first used at 297/// file scope. lazily create a decl for it. ForRedeclaration is true 298/// if we're creating this built-in in anticipation of redeclaring the 299/// built-in. 300NamedDecl *Sema::LazilyCreateBuiltin(IdentifierInfo *II, unsigned bid, 301 Scope *S, bool ForRedeclaration, 302 SourceLocation Loc) { 303 Builtin::ID BID = (Builtin::ID)bid; 304 305 if (Context.BuiltinInfo.hasVAListUse(BID)) 306 InitBuiltinVaListType(); 307 308 Builtin::Context::GetBuiltinTypeError Error; 309 QualType R = Context.BuiltinInfo.GetBuiltinType(BID, Context, Error); 310 switch (Error) { 311 case Builtin::Context::GE_None: 312 // Okay 313 break; 314 315 case Builtin::Context::GE_Missing_FILE: 316 if (ForRedeclaration) 317 Diag(Loc, diag::err_implicit_decl_requires_stdio) 318 << Context.BuiltinInfo.GetName(BID); 319 return 0; 320 } 321 322 if (!ForRedeclaration && Context.BuiltinInfo.isPredefinedLibFunction(BID)) { 323 Diag(Loc, diag::ext_implicit_lib_function_decl) 324 << Context.BuiltinInfo.GetName(BID) 325 << R; 326 if (Context.BuiltinInfo.getHeaderName(BID) && 327 Diags.getDiagnosticMapping(diag::ext_implicit_lib_function_decl) 328 != diag::MAP_IGNORE) 329 Diag(Loc, diag::note_please_include_header) 330 << Context.BuiltinInfo.getHeaderName(BID) 331 << Context.BuiltinInfo.GetName(BID); 332 } 333 334 FunctionDecl *New = FunctionDecl::Create(Context, 335 Context.getTranslationUnitDecl(), 336 Loc, II, R, 337 FunctionDecl::Extern, false); 338 New->setImplicit(); 339 340 // Create Decl objects for each parameter, adding them to the 341 // FunctionDecl. 342 if (FunctionTypeProto *FT = dyn_cast<FunctionTypeProto>(R)) { 343 llvm::SmallVector<ParmVarDecl*, 16> Params; 344 for (unsigned i = 0, e = FT->getNumArgs(); i != e; ++i) 345 Params.push_back(ParmVarDecl::Create(Context, New, SourceLocation(), 0, 346 FT->getArgType(i), VarDecl::None, 0)); 347 New->setParams(Context, &Params[0], Params.size()); 348 } 349 350 AddKnownFunctionAttributes(New); 351 352 // TUScope is the translation-unit scope to insert this function into. 353 // FIXME: This is hideous. We need to teach PushOnScopeChains to 354 // relate Scopes to DeclContexts, and probably eliminate CurContext 355 // entirely, but we're not there yet. 356 DeclContext *SavedContext = CurContext; 357 CurContext = Context.getTranslationUnitDecl(); 358 PushOnScopeChains(New, TUScope); 359 CurContext = SavedContext; 360 return New; 361} 362 363/// GetStdNamespace - This method gets the C++ "std" namespace. This is where 364/// everything from the standard library is defined. 365NamespaceDecl *Sema::GetStdNamespace() { 366 if (!StdNamespace) { 367 IdentifierInfo *StdIdent = &PP.getIdentifierTable().get("std"); 368 DeclContext *Global = Context.getTranslationUnitDecl(); 369 Decl *Std = LookupQualifiedName(Global, StdIdent, LookupNamespaceName); 370 StdNamespace = dyn_cast_or_null<NamespaceDecl>(Std); 371 } 372 return StdNamespace; 373} 374 375/// MergeTypeDefDecl - We just parsed a typedef 'New' which has the 376/// same name and scope as a previous declaration 'Old'. Figure out 377/// how to resolve this situation, merging decls or emitting 378/// diagnostics as appropriate. Returns true if there was an error, 379/// false otherwise. 380/// 381bool Sema::MergeTypeDefDecl(TypedefDecl *New, Decl *OldD) { 382 bool objc_types = false; 383 // Allow multiple definitions for ObjC built-in typedefs. 384 // FIXME: Verify the underlying types are equivalent! 385 if (getLangOptions().ObjC1) { 386 const IdentifierInfo *TypeID = New->getIdentifier(); 387 switch (TypeID->getLength()) { 388 default: break; 389 case 2: 390 if (!TypeID->isStr("id")) 391 break; 392 Context.setObjCIdType(New); 393 objc_types = true; 394 break; 395 case 5: 396 if (!TypeID->isStr("Class")) 397 break; 398 Context.setObjCClassType(New); 399 objc_types = true; 400 return false; 401 case 3: 402 if (!TypeID->isStr("SEL")) 403 break; 404 Context.setObjCSelType(New); 405 objc_types = true; 406 return false; 407 case 8: 408 if (!TypeID->isStr("Protocol")) 409 break; 410 Context.setObjCProtoType(New->getUnderlyingType()); 411 objc_types = true; 412 return false; 413 } 414 // Fall through - the typedef name was not a builtin type. 415 } 416 // Verify the old decl was also a type. 417 TypeDecl *Old = dyn_cast<TypeDecl>(OldD); 418 if (!Old) { 419 Diag(New->getLocation(), diag::err_redefinition_different_kind) 420 << New->getDeclName(); 421 if (!objc_types) 422 Diag(OldD->getLocation(), diag::note_previous_definition); 423 return true; 424 } 425 426 // Determine the "old" type we'll use for checking and diagnostics. 427 QualType OldType; 428 if (TypedefDecl *OldTypedef = dyn_cast<TypedefDecl>(Old)) 429 OldType = OldTypedef->getUnderlyingType(); 430 else 431 OldType = Context.getTypeDeclType(Old); 432 433 // If the typedef types are not identical, reject them in all languages and 434 // with any extensions enabled. 435 436 if (OldType != New->getUnderlyingType() && 437 Context.getCanonicalType(OldType) != 438 Context.getCanonicalType(New->getUnderlyingType())) { 439 Diag(New->getLocation(), diag::err_redefinition_different_typedef) 440 << New->getUnderlyingType() << OldType; 441 if (!objc_types) 442 Diag(Old->getLocation(), diag::note_previous_definition); 443 return true; 444 } 445 if (objc_types) return false; 446 if (getLangOptions().Microsoft) return false; 447 448 // C++ [dcl.typedef]p2: 449 // In a given non-class scope, a typedef specifier can be used to 450 // redefine the name of any type declared in that scope to refer 451 // to the type to which it already refers. 452 if (getLangOptions().CPlusPlus && !isa<CXXRecordDecl>(CurContext)) 453 return false; 454 455 // In C, redeclaration of a type is a constraint violation (6.7.2.3p1). 456 // Apparently GCC, Intel, and Sun all silently ignore the redeclaration if 457 // *either* declaration is in a system header. The code below implements 458 // this adhoc compatibility rule. FIXME: The following code will not 459 // work properly when compiling ".i" files (containing preprocessed output). 460 if (PP.getDiagnostics().getSuppressSystemWarnings()) { 461 SourceManager &SrcMgr = Context.getSourceManager(); 462 if (SrcMgr.isInSystemHeader(Old->getLocation())) 463 return false; 464 if (SrcMgr.isInSystemHeader(New->getLocation())) 465 return false; 466 } 467 468 Diag(New->getLocation(), diag::err_redefinition) << New->getDeclName(); 469 Diag(Old->getLocation(), diag::note_previous_definition); 470 return true; 471} 472 473/// DeclhasAttr - returns true if decl Declaration already has the target 474/// attribute. 475static bool DeclHasAttr(const Decl *decl, const Attr *target) { 476 for (const Attr *attr = decl->getAttrs(); attr; attr = attr->getNext()) 477 if (attr->getKind() == target->getKind()) 478 return true; 479 480 return false; 481} 482 483/// MergeAttributes - append attributes from the Old decl to the New one. 484static void MergeAttributes(Decl *New, Decl *Old) { 485 Attr *attr = const_cast<Attr*>(Old->getAttrs()), *tmp; 486 487 while (attr) { 488 tmp = attr; 489 attr = attr->getNext(); 490 491 if (!DeclHasAttr(New, tmp) && tmp->isMerged()) { 492 tmp->setInherited(true); 493 New->addAttr(tmp); 494 } else { 495 tmp->setNext(0); 496 delete(tmp); 497 } 498 } 499 500 Old->invalidateAttrs(); 501} 502 503/// MergeFunctionDecl - We just parsed a function 'New' from 504/// declarator D which has the same name and scope as a previous 505/// declaration 'Old'. Figure out how to resolve this situation, 506/// merging decls or emitting diagnostics as appropriate. 507/// 508/// In C++, New and Old must be declarations that are not 509/// overloaded. Use IsOverload to determine whether New and Old are 510/// overloaded, and to select the Old declaration that New should be 511/// merged with. 512/// 513/// Returns true if there was an error, false otherwise. 514bool Sema::MergeFunctionDecl(FunctionDecl *New, Decl *OldD) { 515 assert(!isa<OverloadedFunctionDecl>(OldD) && 516 "Cannot merge with an overloaded function declaration"); 517 518 // Verify the old decl was also a function. 519 FunctionDecl *Old = dyn_cast<FunctionDecl>(OldD); 520 if (!Old) { 521 Diag(New->getLocation(), diag::err_redefinition_different_kind) 522 << New->getDeclName(); 523 Diag(OldD->getLocation(), diag::note_previous_definition); 524 return true; 525 } 526 527 // Determine whether the previous declaration was a definition, 528 // implicit declaration, or a declaration. 529 diag::kind PrevDiag; 530 if (Old->isThisDeclarationADefinition()) 531 PrevDiag = diag::note_previous_definition; 532 else if (Old->isImplicit()) 533 PrevDiag = diag::note_previous_implicit_declaration; 534 else 535 PrevDiag = diag::note_previous_declaration; 536 537 QualType OldQType = Context.getCanonicalType(Old->getType()); 538 QualType NewQType = Context.getCanonicalType(New->getType()); 539 540 if (getLangOptions().CPlusPlus) { 541 // (C++98 13.1p2): 542 // Certain function declarations cannot be overloaded: 543 // -- Function declarations that differ only in the return type 544 // cannot be overloaded. 545 QualType OldReturnType 546 = cast<FunctionType>(OldQType.getTypePtr())->getResultType(); 547 QualType NewReturnType 548 = cast<FunctionType>(NewQType.getTypePtr())->getResultType(); 549 if (OldReturnType != NewReturnType) { 550 Diag(New->getLocation(), diag::err_ovl_diff_return_type); 551 Diag(Old->getLocation(), PrevDiag) << Old << Old->getType(); 552 return true; 553 } 554 555 const CXXMethodDecl* OldMethod = dyn_cast<CXXMethodDecl>(Old); 556 const CXXMethodDecl* NewMethod = dyn_cast<CXXMethodDecl>(New); 557 if (OldMethod && NewMethod) { 558 // -- Member function declarations with the same name and the 559 // same parameter types cannot be overloaded if any of them 560 // is a static member function declaration. 561 if (OldMethod->isStatic() || NewMethod->isStatic()) { 562 Diag(New->getLocation(), diag::err_ovl_static_nonstatic_member); 563 Diag(Old->getLocation(), PrevDiag) << Old << Old->getType(); 564 return true; 565 } 566 567 // C++ [class.mem]p1: 568 // [...] A member shall not be declared twice in the 569 // member-specification, except that a nested class or member 570 // class template can be declared and then later defined. 571 if (OldMethod->getLexicalDeclContext() == 572 NewMethod->getLexicalDeclContext()) { 573 unsigned NewDiag; 574 if (isa<CXXConstructorDecl>(OldMethod)) 575 NewDiag = diag::err_constructor_redeclared; 576 else if (isa<CXXDestructorDecl>(NewMethod)) 577 NewDiag = diag::err_destructor_redeclared; 578 else if (isa<CXXConversionDecl>(NewMethod)) 579 NewDiag = diag::err_conv_function_redeclared; 580 else 581 NewDiag = diag::err_member_redeclared; 582 583 Diag(New->getLocation(), NewDiag); 584 Diag(Old->getLocation(), PrevDiag) << Old << Old->getType(); 585 } 586 } 587 588 // (C++98 8.3.5p3): 589 // All declarations for a function shall agree exactly in both the 590 // return type and the parameter-type-list. 591 if (OldQType == NewQType) { 592 // We have a redeclaration. 593 MergeAttributes(New, Old); 594 595 // Merge the "deleted" flag. 596 if (Old->isDeleted()) 597 New->setDeleted(); 598 599 return MergeCXXFunctionDecl(New, Old); 600 } 601 602 // Fall through for conflicting redeclarations and redefinitions. 603 } 604 605 // C: Function types need to be compatible, not identical. This handles 606 // duplicate function decls like "void f(int); void f(enum X);" properly. 607 if (!getLangOptions().CPlusPlus && 608 Context.typesAreCompatible(OldQType, NewQType)) { 609 const FunctionType *NewFuncType = NewQType->getAsFunctionType(); 610 const FunctionTypeProto *OldProto = 0; 611 if (isa<FunctionTypeNoProto>(NewFuncType) && 612 (OldProto = OldQType->getAsFunctionTypeProto())) { 613 // The old declaration provided a function prototype, but the 614 // new declaration does not. Merge in the prototype. 615 llvm::SmallVector<QualType, 16> ParamTypes(OldProto->arg_type_begin(), 616 OldProto->arg_type_end()); 617 NewQType = Context.getFunctionType(NewFuncType->getResultType(), 618 &ParamTypes[0], ParamTypes.size(), 619 OldProto->isVariadic(), 620 OldProto->getTypeQuals()); 621 New->setType(NewQType); 622 New->setInheritedPrototype(); 623 624 // Synthesize a parameter for each argument type. 625 llvm::SmallVector<ParmVarDecl*, 16> Params; 626 for (FunctionTypeProto::arg_type_iterator 627 ParamType = OldProto->arg_type_begin(), 628 ParamEnd = OldProto->arg_type_end(); 629 ParamType != ParamEnd; ++ParamType) { 630 ParmVarDecl *Param = ParmVarDecl::Create(Context, New, 631 SourceLocation(), 0, 632 *ParamType, VarDecl::None, 633 0); 634 Param->setImplicit(); 635 Params.push_back(Param); 636 } 637 638 New->setParams(Context, &Params[0], Params.size()); 639 640 } 641 642 MergeAttributes(New, Old); 643 644 // Merge the "deleted" flag. 645 if (Old->isDeleted()) 646 New->setDeleted(); 647 648 return false; 649 } 650 651 // A function that has already been declared has been redeclared or defined 652 // with a different type- show appropriate diagnostic 653 if (unsigned BuiltinID = Old->getBuiltinID(Context)) { 654 // The user has declared a builtin function with an incompatible 655 // signature. 656 if (Context.BuiltinInfo.isPredefinedLibFunction(BuiltinID)) { 657 // The function the user is redeclaring is a library-defined 658 // function like 'malloc' or 'printf'. Warn about the 659 // redeclaration, then ignore it. 660 Diag(New->getLocation(), diag::warn_redecl_library_builtin) << New; 661 Diag(Old->getLocation(), diag::note_previous_builtin_declaration) 662 << Old << Old->getType(); 663 return true; 664 } 665 666 PrevDiag = diag::note_previous_builtin_declaration; 667 } 668 669 Diag(New->getLocation(), diag::err_conflicting_types) << New->getDeclName(); 670 Diag(Old->getLocation(), PrevDiag) << Old << Old->getType(); 671 return true; 672} 673 674/// Predicate for C "tentative" external object definitions (C99 6.9.2). 675static bool isTentativeDefinition(VarDecl *VD) { 676 if (VD->isFileVarDecl()) 677 return (!VD->getInit() && 678 (VD->getStorageClass() == VarDecl::None || 679 VD->getStorageClass() == VarDecl::Static)); 680 return false; 681} 682 683/// CheckForFileScopedRedefinitions - Make sure we forgo redefinition errors 684/// when dealing with C "tentative" external object definitions (C99 6.9.2). 685void Sema::CheckForFileScopedRedefinitions(Scope *S, VarDecl *VD) { 686 bool VDIsTentative = isTentativeDefinition(VD); 687 bool VDIsIncompleteArray = VD->getType()->isIncompleteArrayType(); 688 689 // FIXME: I don't think this will actually see all of the 690 // redefinitions. Can't we check this property on-the-fly? 691 for (IdentifierResolver::iterator I = IdResolver.begin(VD->getIdentifier()), 692 E = IdResolver.end(); 693 I != E; ++I) { 694 if (*I != VD && isDeclInScope(*I, VD->getDeclContext(), S)) { 695 VarDecl *OldDecl = dyn_cast<VarDecl>(*I); 696 697 // Handle the following case: 698 // int a[10]; 699 // int a[]; - the code below makes sure we set the correct type. 700 // int a[11]; - this is an error, size isn't 10. 701 if (OldDecl && VDIsTentative && VDIsIncompleteArray && 702 OldDecl->getType()->isConstantArrayType()) 703 VD->setType(OldDecl->getType()); 704 705 // Check for "tentative" definitions. We can't accomplish this in 706 // MergeVarDecl since the initializer hasn't been attached. 707 if (!OldDecl || isTentativeDefinition(OldDecl) || VDIsTentative) 708 continue; 709 710 // Handle __private_extern__ just like extern. 711 if (OldDecl->getStorageClass() != VarDecl::Extern && 712 OldDecl->getStorageClass() != VarDecl::PrivateExtern && 713 VD->getStorageClass() != VarDecl::Extern && 714 VD->getStorageClass() != VarDecl::PrivateExtern) { 715 Diag(VD->getLocation(), diag::err_redefinition) << VD->getDeclName(); 716 Diag(OldDecl->getLocation(), diag::note_previous_definition); 717 // One redefinition error is enough. 718 break; 719 } 720 } 721 } 722} 723 724/// MergeVarDecl - We just parsed a variable 'New' which has the same name 725/// and scope as a previous declaration 'Old'. Figure out how to resolve this 726/// situation, merging decls or emitting diagnostics as appropriate. 727/// 728/// Tentative definition rules (C99 6.9.2p2) are checked by 729/// FinalizeDeclaratorGroup. Unfortunately, we can't analyze tentative 730/// definitions here, since the initializer hasn't been attached. 731/// 732bool Sema::MergeVarDecl(VarDecl *New, Decl *OldD) { 733 // Verify the old decl was also a variable. 734 VarDecl *Old = dyn_cast<VarDecl>(OldD); 735 if (!Old) { 736 Diag(New->getLocation(), diag::err_redefinition_different_kind) 737 << New->getDeclName(); 738 Diag(OldD->getLocation(), diag::note_previous_definition); 739 return true; 740 } 741 742 MergeAttributes(New, Old); 743 744 // Merge the types 745 QualType MergedT = Context.mergeTypes(New->getType(), Old->getType()); 746 if (MergedT.isNull()) { 747 Diag(New->getLocation(), diag::err_redefinition_different_type) 748 << New->getDeclName(); 749 Diag(Old->getLocation(), diag::note_previous_definition); 750 return true; 751 } 752 New->setType(MergedT); 753 // C99 6.2.2p4: Check if we have a static decl followed by a non-static. 754 if (New->getStorageClass() == VarDecl::Static && 755 (Old->getStorageClass() == VarDecl::None || 756 Old->getStorageClass() == VarDecl::Extern)) { 757 Diag(New->getLocation(), diag::err_static_non_static) << New->getDeclName(); 758 Diag(Old->getLocation(), diag::note_previous_definition); 759 return true; 760 } 761 // C99 6.2.2p4: Check if we have a non-static decl followed by a static. 762 if (New->getStorageClass() != VarDecl::Static && 763 Old->getStorageClass() == VarDecl::Static) { 764 Diag(New->getLocation(), diag::err_non_static_static) << New->getDeclName(); 765 Diag(Old->getLocation(), diag::note_previous_definition); 766 return true; 767 } 768 // Variables with external linkage are analyzed in FinalizeDeclaratorGroup. 769 if (New->getStorageClass() != VarDecl::Extern && !New->isFileVarDecl()) { 770 Diag(New->getLocation(), diag::err_redefinition) << New->getDeclName(); 771 Diag(Old->getLocation(), diag::note_previous_definition); 772 return true; 773 } 774 return false; 775} 776 777/// CheckParmsForFunctionDef - Check that the parameters of the given 778/// function are appropriate for the definition of a function. This 779/// takes care of any checks that cannot be performed on the 780/// declaration itself, e.g., that the types of each of the function 781/// parameters are complete. 782bool Sema::CheckParmsForFunctionDef(FunctionDecl *FD) { 783 bool HasInvalidParm = false; 784 for (unsigned p = 0, NumParams = FD->getNumParams(); p < NumParams; ++p) { 785 ParmVarDecl *Param = FD->getParamDecl(p); 786 787 // C99 6.7.5.3p4: the parameters in a parameter type list in a 788 // function declarator that is part of a function definition of 789 // that function shall not have incomplete type. 790 if (!Param->isInvalidDecl() && 791 DiagnoseIncompleteType(Param->getLocation(), Param->getType(), 792 diag::err_typecheck_decl_incomplete_type)) { 793 Param->setInvalidDecl(); 794 HasInvalidParm = true; 795 } 796 797 // C99 6.9.1p5: If the declarator includes a parameter type list, the 798 // declaration of each parameter shall include an identifier. 799 if (Param->getIdentifier() == 0 && 800 !Param->isImplicit() && 801 !getLangOptions().CPlusPlus) 802 Diag(Param->getLocation(), diag::err_parameter_name_omitted); 803 } 804 805 return HasInvalidParm; 806} 807 808/// ParsedFreeStandingDeclSpec - This method is invoked when a declspec with 809/// no declarator (e.g. "struct foo;") is parsed. 810Sema::DeclTy *Sema::ParsedFreeStandingDeclSpec(Scope *S, DeclSpec &DS) { 811 TagDecl *Tag = 0; 812 if (DS.getTypeSpecType() == DeclSpec::TST_class || 813 DS.getTypeSpecType() == DeclSpec::TST_struct || 814 DS.getTypeSpecType() == DeclSpec::TST_union || 815 DS.getTypeSpecType() == DeclSpec::TST_enum) 816 Tag = dyn_cast<TagDecl>(static_cast<Decl *>(DS.getTypeRep())); 817 818 if (RecordDecl *Record = dyn_cast_or_null<RecordDecl>(Tag)) { 819 if (!Record->getDeclName() && Record->isDefinition() && 820 DS.getStorageClassSpec() != DeclSpec::SCS_typedef) 821 return BuildAnonymousStructOrUnion(S, DS, Record); 822 823 // Microsoft allows unnamed struct/union fields. Don't complain 824 // about them. 825 // FIXME: Should we support Microsoft's extensions in this area? 826 if (Record->getDeclName() && getLangOptions().Microsoft) 827 return Tag; 828 } 829 830 if (!DS.isMissingDeclaratorOk() && 831 DS.getTypeSpecType() != DeclSpec::TST_error) { 832 // Warn about typedefs of enums without names, since this is an 833 // extension in both Microsoft an GNU. 834 if (DS.getStorageClassSpec() == DeclSpec::SCS_typedef && 835 Tag && isa<EnumDecl>(Tag)) { 836 Diag(DS.getSourceRange().getBegin(), diag::ext_typedef_without_a_name) 837 << DS.getSourceRange(); 838 return Tag; 839 } 840 841 Diag(DS.getSourceRange().getBegin(), diag::err_no_declarators) 842 << DS.getSourceRange(); 843 return 0; 844 } 845 846 return Tag; 847} 848 849/// InjectAnonymousStructOrUnionMembers - Inject the members of the 850/// anonymous struct or union AnonRecord into the owning context Owner 851/// and scope S. This routine will be invoked just after we realize 852/// that an unnamed union or struct is actually an anonymous union or 853/// struct, e.g., 854/// 855/// @code 856/// union { 857/// int i; 858/// float f; 859/// }; // InjectAnonymousStructOrUnionMembers called here to inject i and 860/// // f into the surrounding scope.x 861/// @endcode 862/// 863/// This routine is recursive, injecting the names of nested anonymous 864/// structs/unions into the owning context and scope as well. 865bool Sema::InjectAnonymousStructOrUnionMembers(Scope *S, DeclContext *Owner, 866 RecordDecl *AnonRecord) { 867 bool Invalid = false; 868 for (RecordDecl::field_iterator F = AnonRecord->field_begin(), 869 FEnd = AnonRecord->field_end(); 870 F != FEnd; ++F) { 871 if ((*F)->getDeclName()) { 872 NamedDecl *PrevDecl = LookupQualifiedName(Owner, (*F)->getDeclName(), 873 LookupOrdinaryName, true); 874 if (PrevDecl && !isa<TagDecl>(PrevDecl)) { 875 // C++ [class.union]p2: 876 // The names of the members of an anonymous union shall be 877 // distinct from the names of any other entity in the 878 // scope in which the anonymous union is declared. 879 unsigned diagKind 880 = AnonRecord->isUnion()? diag::err_anonymous_union_member_redecl 881 : diag::err_anonymous_struct_member_redecl; 882 Diag((*F)->getLocation(), diagKind) 883 << (*F)->getDeclName(); 884 Diag(PrevDecl->getLocation(), diag::note_previous_declaration); 885 Invalid = true; 886 } else { 887 // C++ [class.union]p2: 888 // For the purpose of name lookup, after the anonymous union 889 // definition, the members of the anonymous union are 890 // considered to have been defined in the scope in which the 891 // anonymous union is declared. 892 Owner->makeDeclVisibleInContext(*F); 893 S->AddDecl(*F); 894 IdResolver.AddDecl(*F); 895 } 896 } else if (const RecordType *InnerRecordType 897 = (*F)->getType()->getAsRecordType()) { 898 RecordDecl *InnerRecord = InnerRecordType->getDecl(); 899 if (InnerRecord->isAnonymousStructOrUnion()) 900 Invalid = Invalid || 901 InjectAnonymousStructOrUnionMembers(S, Owner, InnerRecord); 902 } 903 } 904 905 return Invalid; 906} 907 908/// ActOnAnonymousStructOrUnion - Handle the declaration of an 909/// anonymous structure or union. Anonymous unions are a C++ feature 910/// (C++ [class.union]) and a GNU C extension; anonymous structures 911/// are a GNU C and GNU C++ extension. 912Sema::DeclTy *Sema::BuildAnonymousStructOrUnion(Scope *S, DeclSpec &DS, 913 RecordDecl *Record) { 914 DeclContext *Owner = Record->getDeclContext(); 915 916 // Diagnose whether this anonymous struct/union is an extension. 917 if (Record->isUnion() && !getLangOptions().CPlusPlus) 918 Diag(Record->getLocation(), diag::ext_anonymous_union); 919 else if (!Record->isUnion()) 920 Diag(Record->getLocation(), diag::ext_anonymous_struct); 921 922 // C and C++ require different kinds of checks for anonymous 923 // structs/unions. 924 bool Invalid = false; 925 if (getLangOptions().CPlusPlus) { 926 const char* PrevSpec = 0; 927 // C++ [class.union]p3: 928 // Anonymous unions declared in a named namespace or in the 929 // global namespace shall be declared static. 930 if (DS.getStorageClassSpec() != DeclSpec::SCS_static && 931 (isa<TranslationUnitDecl>(Owner) || 932 (isa<NamespaceDecl>(Owner) && 933 cast<NamespaceDecl>(Owner)->getDeclName()))) { 934 Diag(Record->getLocation(), diag::err_anonymous_union_not_static); 935 Invalid = true; 936 937 // Recover by adding 'static'. 938 DS.SetStorageClassSpec(DeclSpec::SCS_static, SourceLocation(), PrevSpec); 939 } 940 // C++ [class.union]p3: 941 // A storage class is not allowed in a declaration of an 942 // anonymous union in a class scope. 943 else if (DS.getStorageClassSpec() != DeclSpec::SCS_unspecified && 944 isa<RecordDecl>(Owner)) { 945 Diag(DS.getStorageClassSpecLoc(), 946 diag::err_anonymous_union_with_storage_spec); 947 Invalid = true; 948 949 // Recover by removing the storage specifier. 950 DS.SetStorageClassSpec(DeclSpec::SCS_unspecified, SourceLocation(), 951 PrevSpec); 952 } 953 954 // C++ [class.union]p2: 955 // The member-specification of an anonymous union shall only 956 // define non-static data members. [Note: nested types and 957 // functions cannot be declared within an anonymous union. ] 958 for (DeclContext::decl_iterator Mem = Record->decls_begin(), 959 MemEnd = Record->decls_end(); 960 Mem != MemEnd; ++Mem) { 961 if (FieldDecl *FD = dyn_cast<FieldDecl>(*Mem)) { 962 // C++ [class.union]p3: 963 // An anonymous union shall not have private or protected 964 // members (clause 11). 965 if (FD->getAccess() == AS_protected || FD->getAccess() == AS_private) { 966 Diag(FD->getLocation(), diag::err_anonymous_record_nonpublic_member) 967 << (int)Record->isUnion() << (int)(FD->getAccess() == AS_protected); 968 Invalid = true; 969 } 970 } else if ((*Mem)->isImplicit()) { 971 // Any implicit members are fine. 972 } else if (isa<TagDecl>(*Mem) && (*Mem)->getDeclContext() != Record) { 973 // This is a type that showed up in an 974 // elaborated-type-specifier inside the anonymous struct or 975 // union, but which actually declares a type outside of the 976 // anonymous struct or union. It's okay. 977 } else if (RecordDecl *MemRecord = dyn_cast<RecordDecl>(*Mem)) { 978 if (!MemRecord->isAnonymousStructOrUnion() && 979 MemRecord->getDeclName()) { 980 // This is a nested type declaration. 981 Diag(MemRecord->getLocation(), diag::err_anonymous_record_with_type) 982 << (int)Record->isUnion(); 983 Invalid = true; 984 } 985 } else { 986 // We have something that isn't a non-static data 987 // member. Complain about it. 988 unsigned DK = diag::err_anonymous_record_bad_member; 989 if (isa<TypeDecl>(*Mem)) 990 DK = diag::err_anonymous_record_with_type; 991 else if (isa<FunctionDecl>(*Mem)) 992 DK = diag::err_anonymous_record_with_function; 993 else if (isa<VarDecl>(*Mem)) 994 DK = diag::err_anonymous_record_with_static; 995 Diag((*Mem)->getLocation(), DK) 996 << (int)Record->isUnion(); 997 Invalid = true; 998 } 999 } 1000 } else { 1001 // FIXME: Check GNU C semantics 1002 if (Record->isUnion() && !Owner->isRecord()) { 1003 Diag(Record->getLocation(), diag::err_anonymous_union_not_member) 1004 << (int)getLangOptions().CPlusPlus; 1005 Invalid = true; 1006 } 1007 } 1008 1009 if (!Record->isUnion() && !Owner->isRecord()) { 1010 Diag(Record->getLocation(), diag::err_anonymous_struct_not_member) 1011 << (int)getLangOptions().CPlusPlus; 1012 Invalid = true; 1013 } 1014 1015 // Create a declaration for this anonymous struct/union. 1016 NamedDecl *Anon = 0; 1017 if (RecordDecl *OwningClass = dyn_cast<RecordDecl>(Owner)) { 1018 Anon = FieldDecl::Create(Context, OwningClass, Record->getLocation(), 1019 /*IdentifierInfo=*/0, 1020 Context.getTypeDeclType(Record), 1021 /*BitWidth=*/0, /*Mutable=*/false); 1022 Anon->setAccess(AS_public); 1023 if (getLangOptions().CPlusPlus) 1024 FieldCollector->Add(cast<FieldDecl>(Anon)); 1025 } else { 1026 VarDecl::StorageClass SC; 1027 switch (DS.getStorageClassSpec()) { 1028 default: assert(0 && "Unknown storage class!"); 1029 case DeclSpec::SCS_unspecified: SC = VarDecl::None; break; 1030 case DeclSpec::SCS_extern: SC = VarDecl::Extern; break; 1031 case DeclSpec::SCS_static: SC = VarDecl::Static; break; 1032 case DeclSpec::SCS_auto: SC = VarDecl::Auto; break; 1033 case DeclSpec::SCS_register: SC = VarDecl::Register; break; 1034 case DeclSpec::SCS_private_extern: SC = VarDecl::PrivateExtern; break; 1035 case DeclSpec::SCS_mutable: 1036 // mutable can only appear on non-static class members, so it's always 1037 // an error here 1038 Diag(Record->getLocation(), diag::err_mutable_nonmember); 1039 Invalid = true; 1040 SC = VarDecl::None; 1041 break; 1042 } 1043 1044 Anon = VarDecl::Create(Context, Owner, Record->getLocation(), 1045 /*IdentifierInfo=*/0, 1046 Context.getTypeDeclType(Record), 1047 SC, DS.getSourceRange().getBegin()); 1048 } 1049 Anon->setImplicit(); 1050 1051 // Add the anonymous struct/union object to the current 1052 // context. We'll be referencing this object when we refer to one of 1053 // its members. 1054 Owner->addDecl(Anon); 1055 1056 // Inject the members of the anonymous struct/union into the owning 1057 // context and into the identifier resolver chain for name lookup 1058 // purposes. 1059 if (InjectAnonymousStructOrUnionMembers(S, Owner, Record)) 1060 Invalid = true; 1061 1062 // Mark this as an anonymous struct/union type. Note that we do not 1063 // do this until after we have already checked and injected the 1064 // members of this anonymous struct/union type, because otherwise 1065 // the members could be injected twice: once by DeclContext when it 1066 // builds its lookup table, and once by 1067 // InjectAnonymousStructOrUnionMembers. 1068 Record->setAnonymousStructOrUnion(true); 1069 1070 if (Invalid) 1071 Anon->setInvalidDecl(); 1072 1073 return Anon; 1074} 1075 1076bool Sema::CheckSingleInitializer(Expr *&Init, QualType DeclType, 1077 bool DirectInit) { 1078 // Get the type before calling CheckSingleAssignmentConstraints(), since 1079 // it can promote the expression. 1080 QualType InitType = Init->getType(); 1081 1082 if (getLangOptions().CPlusPlus) { 1083 // FIXME: I dislike this error message. A lot. 1084 if (PerformImplicitConversion(Init, DeclType, "initializing", DirectInit)) 1085 return Diag(Init->getSourceRange().getBegin(), 1086 diag::err_typecheck_convert_incompatible) 1087 << DeclType << Init->getType() << "initializing" 1088 << Init->getSourceRange(); 1089 1090 return false; 1091 } 1092 1093 AssignConvertType ConvTy = CheckSingleAssignmentConstraints(DeclType, Init); 1094 return DiagnoseAssignmentResult(ConvTy, Init->getLocStart(), DeclType, 1095 InitType, Init, "initializing"); 1096} 1097 1098bool Sema::CheckStringLiteralInit(StringLiteral *strLiteral, QualType &DeclT) { 1099 const ArrayType *AT = Context.getAsArrayType(DeclT); 1100 1101 if (const IncompleteArrayType *IAT = dyn_cast<IncompleteArrayType>(AT)) { 1102 // C99 6.7.8p14. We have an array of character type with unknown size 1103 // being initialized to a string literal. 1104 llvm::APSInt ConstVal(32); 1105 ConstVal = strLiteral->getByteLength() + 1; 1106 // Return a new array type (C99 6.7.8p22). 1107 DeclT = Context.getConstantArrayType(IAT->getElementType(), ConstVal, 1108 ArrayType::Normal, 0); 1109 } else { 1110 const ConstantArrayType *CAT = cast<ConstantArrayType>(AT); 1111 // C99 6.7.8p14. We have an array of character type with known size. 1112 // FIXME: Avoid truncation for 64-bit length strings. 1113 if (strLiteral->getByteLength() > (unsigned)CAT->getSize().getZExtValue()) 1114 Diag(strLiteral->getSourceRange().getBegin(), 1115 diag::warn_initializer_string_for_char_array_too_long) 1116 << strLiteral->getSourceRange(); 1117 } 1118 // Set type from "char *" to "constant array of char". 1119 strLiteral->setType(DeclT); 1120 // For now, we always return false (meaning success). 1121 return false; 1122} 1123 1124StringLiteral *Sema::IsStringLiteralInit(Expr *Init, QualType DeclType) { 1125 const ArrayType *AT = Context.getAsArrayType(DeclType); 1126 if (AT && AT->getElementType()->isCharType()) { 1127 return dyn_cast<StringLiteral>(Init->IgnoreParens()); 1128 } 1129 return 0; 1130} 1131 1132bool Sema::CheckInitializerTypes(Expr *&Init, QualType &DeclType, 1133 SourceLocation InitLoc, 1134 DeclarationName InitEntity, 1135 bool DirectInit) { 1136 if (DeclType->isDependentType() || Init->isTypeDependent()) 1137 return false; 1138 1139 // C++ [dcl.init.ref]p1: 1140 // A variable declared to be a T&, that is "reference to type T" 1141 // (8.3.2), shall be initialized by an object, or function, of 1142 // type T or by an object that can be converted into a T. 1143 if (DeclType->isReferenceType()) 1144 return CheckReferenceInit(Init, DeclType, 0, false, DirectInit); 1145 1146 // C99 6.7.8p3: The type of the entity to be initialized shall be an array 1147 // of unknown size ("[]") or an object type that is not a variable array type. 1148 if (const VariableArrayType *VAT = Context.getAsVariableArrayType(DeclType)) 1149 return Diag(InitLoc, diag::err_variable_object_no_init) 1150 << VAT->getSizeExpr()->getSourceRange(); 1151 1152 InitListExpr *InitList = dyn_cast<InitListExpr>(Init); 1153 if (!InitList) { 1154 // FIXME: Handle wide strings 1155 if (StringLiteral *strLiteral = IsStringLiteralInit(Init, DeclType)) 1156 return CheckStringLiteralInit(strLiteral, DeclType); 1157 1158 // C++ [dcl.init]p14: 1159 // -- If the destination type is a (possibly cv-qualified) class 1160 // type: 1161 if (getLangOptions().CPlusPlus && DeclType->isRecordType()) { 1162 QualType DeclTypeC = Context.getCanonicalType(DeclType); 1163 QualType InitTypeC = Context.getCanonicalType(Init->getType()); 1164 1165 // -- If the initialization is direct-initialization, or if it is 1166 // copy-initialization where the cv-unqualified version of the 1167 // source type is the same class as, or a derived class of, the 1168 // class of the destination, constructors are considered. 1169 if ((DeclTypeC.getUnqualifiedType() == InitTypeC.getUnqualifiedType()) || 1170 IsDerivedFrom(InitTypeC, DeclTypeC)) { 1171 CXXConstructorDecl *Constructor 1172 = PerformInitializationByConstructor(DeclType, &Init, 1, 1173 InitLoc, Init->getSourceRange(), 1174 InitEntity, 1175 DirectInit? IK_Direct : IK_Copy); 1176 return Constructor == 0; 1177 } 1178 1179 // -- Otherwise (i.e., for the remaining copy-initialization 1180 // cases), user-defined conversion sequences that can 1181 // convert from the source type to the destination type or 1182 // (when a conversion function is used) to a derived class 1183 // thereof are enumerated as described in 13.3.1.4, and the 1184 // best one is chosen through overload resolution 1185 // (13.3). If the conversion cannot be done or is 1186 // ambiguous, the initialization is ill-formed. The 1187 // function selected is called with the initializer 1188 // expression as its argument; if the function is a 1189 // constructor, the call initializes a temporary of the 1190 // destination type. 1191 // FIXME: We're pretending to do copy elision here; return to 1192 // this when we have ASTs for such things. 1193 if (!PerformImplicitConversion(Init, DeclType, "initializing")) 1194 return false; 1195 1196 if (InitEntity) 1197 return Diag(InitLoc, diag::err_cannot_initialize_decl) 1198 << InitEntity << (int)(Init->isLvalue(Context) == Expr::LV_Valid) 1199 << Init->getType() << Init->getSourceRange(); 1200 else 1201 return Diag(InitLoc, diag::err_cannot_initialize_decl_noname) 1202 << DeclType << (int)(Init->isLvalue(Context) == Expr::LV_Valid) 1203 << Init->getType() << Init->getSourceRange(); 1204 } 1205 1206 // C99 6.7.8p16. 1207 if (DeclType->isArrayType()) 1208 return Diag(Init->getLocStart(), diag::err_array_init_list_required) 1209 << Init->getSourceRange(); 1210 1211 return CheckSingleInitializer(Init, DeclType, DirectInit); 1212 } 1213 1214 bool hadError = CheckInitList(InitList, DeclType); 1215 Init = InitList; 1216 return hadError; 1217} 1218 1219/// GetNameForDeclarator - Determine the full declaration name for the 1220/// given Declarator. 1221DeclarationName Sema::GetNameForDeclarator(Declarator &D) { 1222 switch (D.getKind()) { 1223 case Declarator::DK_Abstract: 1224 assert(D.getIdentifier() == 0 && "abstract declarators have no name"); 1225 return DeclarationName(); 1226 1227 case Declarator::DK_Normal: 1228 assert (D.getIdentifier() != 0 && "normal declarators have an identifier"); 1229 return DeclarationName(D.getIdentifier()); 1230 1231 case Declarator::DK_Constructor: { 1232 QualType Ty = QualType::getFromOpaquePtr(D.getDeclaratorIdType()); 1233 Ty = Context.getCanonicalType(Ty); 1234 return Context.DeclarationNames.getCXXConstructorName(Ty); 1235 } 1236 1237 case Declarator::DK_Destructor: { 1238 QualType Ty = QualType::getFromOpaquePtr(D.getDeclaratorIdType()); 1239 Ty = Context.getCanonicalType(Ty); 1240 return Context.DeclarationNames.getCXXDestructorName(Ty); 1241 } 1242 1243 case Declarator::DK_Conversion: { 1244 // FIXME: We'd like to keep the non-canonical type for diagnostics! 1245 QualType Ty = QualType::getFromOpaquePtr(D.getDeclaratorIdType()); 1246 Ty = Context.getCanonicalType(Ty); 1247 return Context.DeclarationNames.getCXXConversionFunctionName(Ty); 1248 } 1249 1250 case Declarator::DK_Operator: 1251 assert(D.getIdentifier() == 0 && "operator names have no identifier"); 1252 return Context.DeclarationNames.getCXXOperatorName( 1253 D.getOverloadedOperator()); 1254 } 1255 1256 assert(false && "Unknown name kind"); 1257 return DeclarationName(); 1258} 1259 1260/// isNearlyMatchingFunction - Determine whether the C++ functions 1261/// Declaration and Definition are "nearly" matching. This heuristic 1262/// is used to improve diagnostics in the case where an out-of-line 1263/// function definition doesn't match any declaration within 1264/// the class or namespace. 1265static bool isNearlyMatchingFunction(ASTContext &Context, 1266 FunctionDecl *Declaration, 1267 FunctionDecl *Definition) { 1268 if (Declaration->param_size() != Definition->param_size()) 1269 return false; 1270 for (unsigned Idx = 0; Idx < Declaration->param_size(); ++Idx) { 1271 QualType DeclParamTy = Declaration->getParamDecl(Idx)->getType(); 1272 QualType DefParamTy = Definition->getParamDecl(Idx)->getType(); 1273 1274 DeclParamTy = Context.getCanonicalType(DeclParamTy.getNonReferenceType()); 1275 DefParamTy = Context.getCanonicalType(DefParamTy.getNonReferenceType()); 1276 if (DeclParamTy.getUnqualifiedType() != DefParamTy.getUnqualifiedType()) 1277 return false; 1278 } 1279 1280 return true; 1281} 1282 1283Sema::DeclTy * 1284Sema::ActOnDeclarator(Scope *S, Declarator &D, DeclTy *lastDecl, 1285 bool IsFunctionDefinition) { 1286 NamedDecl *LastDeclarator = dyn_cast_or_null<NamedDecl>((Decl *)lastDecl); 1287 DeclarationName Name = GetNameForDeclarator(D); 1288 1289 // All of these full declarators require an identifier. If it doesn't have 1290 // one, the ParsedFreeStandingDeclSpec action should be used. 1291 if (!Name) { 1292 if (!D.getInvalidType()) // Reject this if we think it is valid. 1293 Diag(D.getDeclSpec().getSourceRange().getBegin(), 1294 diag::err_declarator_need_ident) 1295 << D.getDeclSpec().getSourceRange() << D.getSourceRange(); 1296 return 0; 1297 } 1298 1299 // The scope passed in may not be a decl scope. Zip up the scope tree until 1300 // we find one that is. 1301 while ((S->getFlags() & Scope::DeclScope) == 0 || 1302 (S->getFlags() & Scope::TemplateParamScope) != 0) 1303 S = S->getParent(); 1304 1305 DeclContext *DC; 1306 NamedDecl *PrevDecl; 1307 NamedDecl *New; 1308 bool InvalidDecl = false; 1309 1310 // See if this is a redefinition of a variable in the same scope. 1311 if (!D.getCXXScopeSpec().isSet() && !D.getCXXScopeSpec().isInvalid()) { 1312 DC = CurContext; 1313 PrevDecl = LookupName(S, Name, LookupOrdinaryName, true, 1314 D.getDeclSpec().getStorageClassSpec() != 1315 DeclSpec::SCS_static, 1316 D.getIdentifierLoc()); 1317 } else { // Something like "int foo::x;" 1318 DC = static_cast<DeclContext*>(D.getCXXScopeSpec().getScopeRep()); 1319 PrevDecl = LookupQualifiedName(DC, Name, LookupOrdinaryName, true); 1320 1321 // C++ 7.3.1.2p2: 1322 // Members (including explicit specializations of templates) of a named 1323 // namespace can also be defined outside that namespace by explicit 1324 // qualification of the name being defined, provided that the entity being 1325 // defined was already declared in the namespace and the definition appears 1326 // after the point of declaration in a namespace that encloses the 1327 // declarations namespace. 1328 // 1329 // Note that we only check the context at this point. We don't yet 1330 // have enough information to make sure that PrevDecl is actually 1331 // the declaration we want to match. For example, given: 1332 // 1333 // class X { 1334 // void f(); 1335 // void f(float); 1336 // }; 1337 // 1338 // void X::f(int) { } // ill-formed 1339 // 1340 // In this case, PrevDecl will point to the overload set 1341 // containing the two f's declared in X, but neither of them 1342 // matches. 1343 1344 // First check whether we named the global scope. 1345 if (isa<TranslationUnitDecl>(DC)) { 1346 Diag(D.getIdentifierLoc(), diag::err_invalid_declarator_global_scope) 1347 << Name << D.getCXXScopeSpec().getRange(); 1348 } else if (!CurContext->Encloses(DC)) { 1349 // The qualifying scope doesn't enclose the original declaration. 1350 // Emit diagnostic based on current scope. 1351 SourceLocation L = D.getIdentifierLoc(); 1352 SourceRange R = D.getCXXScopeSpec().getRange(); 1353 if (isa<FunctionDecl>(CurContext)) 1354 Diag(L, diag::err_invalid_declarator_in_function) << Name << R; 1355 else 1356 Diag(L, diag::err_invalid_declarator_scope) 1357 << Name << cast<NamedDecl>(DC) << R; 1358 InvalidDecl = true; 1359 } 1360 } 1361 1362 if (PrevDecl && PrevDecl->isTemplateParameter()) { 1363 // Maybe we will complain about the shadowed template parameter. 1364 InvalidDecl = InvalidDecl 1365 || DiagnoseTemplateParameterShadow(D.getIdentifierLoc(), PrevDecl); 1366 // Just pretend that we didn't see the previous declaration. 1367 PrevDecl = 0; 1368 } 1369 1370 // In C++, the previous declaration we find might be a tag type 1371 // (class or enum). In this case, the new declaration will hide the 1372 // tag type. Note that this does does not apply if we're declaring a 1373 // typedef (C++ [dcl.typedef]p4). 1374 if (PrevDecl && PrevDecl->getIdentifierNamespace() == Decl::IDNS_Tag && 1375 D.getDeclSpec().getStorageClassSpec() != DeclSpec::SCS_typedef) 1376 PrevDecl = 0; 1377 1378 QualType R = GetTypeForDeclarator(D, S); 1379 if (R.isNull()) { 1380 InvalidDecl = true; 1381 R = Context.IntTy; 1382 } 1383 1384 bool Redeclaration = false; 1385 if (D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_typedef) { 1386 New = ActOnTypedefDeclarator(S, D, DC, R, LastDeclarator, PrevDecl, 1387 InvalidDecl, Redeclaration); 1388 } else if (R.getTypePtr()->isFunctionType()) { 1389 New = ActOnFunctionDeclarator(S, D, DC, R, LastDeclarator, PrevDecl, 1390 IsFunctionDefinition, InvalidDecl, 1391 Redeclaration); 1392 } else { 1393 New = ActOnVariableDeclarator(S, D, DC, R, LastDeclarator, PrevDecl, 1394 InvalidDecl, Redeclaration); 1395 } 1396 1397 if (New == 0) 1398 return 0; 1399 1400 // Set the lexical context. If the declarator has a C++ scope specifier, the 1401 // lexical context will be different from the semantic context. 1402 New->setLexicalDeclContext(CurContext); 1403 1404 // If this has an identifier and is not an invalid redeclaration, 1405 // add it to the scope stack. 1406 if (Name && !(Redeclaration && InvalidDecl)) 1407 PushOnScopeChains(New, S); 1408 // If any semantic error occurred, mark the decl as invalid. 1409 if (D.getInvalidType() || InvalidDecl) 1410 New->setInvalidDecl(); 1411 1412 return New; 1413} 1414 1415/// TryToFixInvalidVariablyModifiedType - Helper method to turn variable array 1416/// types into constant array types in certain situations which would otherwise 1417/// be errors (for GCC compatibility). 1418static QualType TryToFixInvalidVariablyModifiedType(QualType T, 1419 ASTContext &Context, 1420 bool &SizeIsNegative) { 1421 // This method tries to turn a variable array into a constant 1422 // array even when the size isn't an ICE. This is necessary 1423 // for compatibility with code that depends on gcc's buggy 1424 // constant expression folding, like struct {char x[(int)(char*)2];} 1425 SizeIsNegative = false; 1426 1427 if (const PointerType* PTy = dyn_cast<PointerType>(T)) { 1428 QualType Pointee = PTy->getPointeeType(); 1429 QualType FixedType = 1430 TryToFixInvalidVariablyModifiedType(Pointee, Context, SizeIsNegative); 1431 if (FixedType.isNull()) return FixedType; 1432 FixedType = Context.getPointerType(FixedType); 1433 FixedType.setCVRQualifiers(T.getCVRQualifiers()); 1434 return FixedType; 1435 } 1436 1437 const VariableArrayType* VLATy = dyn_cast<VariableArrayType>(T); 1438 if (!VLATy) return QualType(); 1439 1440 Expr::EvalResult EvalResult; 1441 if (!VLATy->getSizeExpr() || 1442 !VLATy->getSizeExpr()->Evaluate(EvalResult, Context)) 1443 return QualType(); 1444 1445 assert(EvalResult.Val.isInt() && "Size expressions must be integers!"); 1446 llvm::APSInt &Res = EvalResult.Val.getInt(); 1447 if (Res >= llvm::APSInt(Res.getBitWidth(), Res.isUnsigned())) 1448 return Context.getConstantArrayType(VLATy->getElementType(), 1449 Res, ArrayType::Normal, 0); 1450 1451 SizeIsNegative = true; 1452 return QualType(); 1453} 1454 1455NamedDecl* 1456Sema::ActOnTypedefDeclarator(Scope* S, Declarator& D, DeclContext* DC, 1457 QualType R, Decl* LastDeclarator, 1458 Decl* PrevDecl, bool& InvalidDecl, 1459 bool &Redeclaration) { 1460 // Typedef declarators cannot be qualified (C++ [dcl.meaning]p1). 1461 if (D.getCXXScopeSpec().isSet()) { 1462 Diag(D.getIdentifierLoc(), diag::err_qualified_typedef_declarator) 1463 << D.getCXXScopeSpec().getRange(); 1464 InvalidDecl = true; 1465 // Pretend we didn't see the scope specifier. 1466 DC = 0; 1467 } 1468 1469 // Check that there are no default arguments (C++ only). 1470 if (getLangOptions().CPlusPlus) 1471 CheckExtraCXXDefaultArguments(D); 1472 1473 TypedefDecl *NewTD = ParseTypedefDecl(S, D, R, LastDeclarator); 1474 if (!NewTD) return 0; 1475 1476 // Handle attributes prior to checking for duplicates in MergeVarDecl 1477 ProcessDeclAttributes(NewTD, D); 1478 // Merge the decl with the existing one if appropriate. If the decl is 1479 // in an outer scope, it isn't the same thing. 1480 if (PrevDecl && isDeclInScope(PrevDecl, DC, S)) { 1481 Redeclaration = true; 1482 if (MergeTypeDefDecl(NewTD, PrevDecl)) 1483 InvalidDecl = true; 1484 } 1485 1486 if (S->getFnParent() == 0) { 1487 QualType T = NewTD->getUnderlyingType(); 1488 // C99 6.7.7p2: If a typedef name specifies a variably modified type 1489 // then it shall have block scope. 1490 if (T->isVariablyModifiedType()) { 1491 bool SizeIsNegative; 1492 QualType FixedTy = 1493 TryToFixInvalidVariablyModifiedType(T, Context, SizeIsNegative); 1494 if (!FixedTy.isNull()) { 1495 Diag(D.getIdentifierLoc(), diag::warn_illegal_constant_array_size); 1496 NewTD->setUnderlyingType(FixedTy); 1497 } else { 1498 if (SizeIsNegative) 1499 Diag(D.getIdentifierLoc(), diag::err_typecheck_negative_array_size); 1500 else if (T->isVariableArrayType()) 1501 Diag(D.getIdentifierLoc(), diag::err_vla_decl_in_file_scope); 1502 else 1503 Diag(D.getIdentifierLoc(), diag::err_vm_decl_in_file_scope); 1504 InvalidDecl = true; 1505 } 1506 } 1507 } 1508 return NewTD; 1509} 1510 1511NamedDecl* 1512Sema::ActOnVariableDeclarator(Scope* S, Declarator& D, DeclContext* DC, 1513 QualType R, Decl* LastDeclarator, 1514 Decl* PrevDecl, bool& InvalidDecl, 1515 bool &Redeclaration) { 1516 DeclarationName Name = GetNameForDeclarator(D); 1517 1518 // Check that there are no default arguments (C++ only). 1519 if (getLangOptions().CPlusPlus) 1520 CheckExtraCXXDefaultArguments(D); 1521 1522 if (R.getTypePtr()->isObjCInterfaceType()) { 1523 Diag(D.getIdentifierLoc(), diag::err_statically_allocated_object); 1524 InvalidDecl = true; 1525 } 1526 1527 VarDecl *NewVD; 1528 VarDecl::StorageClass SC; 1529 switch (D.getDeclSpec().getStorageClassSpec()) { 1530 default: assert(0 && "Unknown storage class!"); 1531 case DeclSpec::SCS_unspecified: SC = VarDecl::None; break; 1532 case DeclSpec::SCS_extern: SC = VarDecl::Extern; break; 1533 case DeclSpec::SCS_static: SC = VarDecl::Static; break; 1534 case DeclSpec::SCS_auto: SC = VarDecl::Auto; break; 1535 case DeclSpec::SCS_register: SC = VarDecl::Register; break; 1536 case DeclSpec::SCS_private_extern: SC = VarDecl::PrivateExtern; break; 1537 case DeclSpec::SCS_mutable: 1538 // mutable can only appear on non-static class members, so it's always 1539 // an error here 1540 Diag(D.getIdentifierLoc(), diag::err_mutable_nonmember); 1541 InvalidDecl = true; 1542 SC = VarDecl::None; 1543 break; 1544 } 1545 1546 IdentifierInfo *II = Name.getAsIdentifierInfo(); 1547 if (!II) { 1548 Diag(D.getIdentifierLoc(), diag::err_bad_variable_name) 1549 << Name.getAsString(); 1550 return 0; 1551 } 1552 1553 if (DC->isRecord()) { 1554 // This is a static data member for a C++ class. 1555 NewVD = CXXClassVarDecl::Create(Context, cast<CXXRecordDecl>(DC), 1556 D.getIdentifierLoc(), II, 1557 R); 1558 } else { 1559 bool ThreadSpecified = D.getDeclSpec().isThreadSpecified(); 1560 if (S->getFnParent() == 0) { 1561 // C99 6.9p2: The storage-class specifiers auto and register shall not 1562 // appear in the declaration specifiers in an external declaration. 1563 if (SC == VarDecl::Auto || SC == VarDecl::Register) { 1564 Diag(D.getIdentifierLoc(), diag::err_typecheck_sclass_fscope); 1565 InvalidDecl = true; 1566 } 1567 } 1568 NewVD = VarDecl::Create(Context, DC, D.getIdentifierLoc(), 1569 II, R, SC, 1570 // FIXME: Move to DeclGroup... 1571 D.getDeclSpec().getSourceRange().getBegin()); 1572 NewVD->setThreadSpecified(ThreadSpecified); 1573 } 1574 NewVD->setNextDeclarator(LastDeclarator); 1575 1576 // Handle attributes prior to checking for duplicates in MergeVarDecl 1577 ProcessDeclAttributes(NewVD, D); 1578 1579 // Handle GNU asm-label extension (encoded as an attribute). 1580 if (Expr *E = (Expr*) D.getAsmLabel()) { 1581 // The parser guarantees this is a string. 1582 StringLiteral *SE = cast<StringLiteral>(E); 1583 NewVD->addAttr(new AsmLabelAttr(std::string(SE->getStrData(), 1584 SE->getByteLength()))); 1585 } 1586 1587 // Emit an error if an address space was applied to decl with local storage. 1588 // This includes arrays of objects with address space qualifiers, but not 1589 // automatic variables that point to other address spaces. 1590 // ISO/IEC TR 18037 S5.1.2 1591 if (NewVD->hasLocalStorage() && (NewVD->getType().getAddressSpace() != 0)) { 1592 Diag(D.getIdentifierLoc(), diag::err_as_qualified_auto_decl); 1593 InvalidDecl = true; 1594 } 1595 1596 if (NewVD->hasLocalStorage() && NewVD->getType().isObjCGCWeak()) { 1597 Diag(D.getIdentifierLoc(), diag::warn_attribute_weak_on_local); 1598 } 1599 1600 // Merge the decl with the existing one if appropriate. If the decl is 1601 // in an outer scope, it isn't the same thing. 1602 if (PrevDecl && isDeclInScope(PrevDecl, DC, S)) { 1603 if (isa<FieldDecl>(PrevDecl) && D.getCXXScopeSpec().isSet()) { 1604 // The user tried to define a non-static data member 1605 // out-of-line (C++ [dcl.meaning]p1). 1606 Diag(NewVD->getLocation(), diag::err_nonstatic_member_out_of_line) 1607 << D.getCXXScopeSpec().getRange(); 1608 NewVD->Destroy(Context); 1609 return 0; 1610 } 1611 1612 Redeclaration = true; 1613 if (MergeVarDecl(NewVD, PrevDecl)) 1614 InvalidDecl = true; 1615 1616 if (D.getCXXScopeSpec().isSet()) { 1617 // No previous declaration in the qualifying scope. 1618 Diag(D.getIdentifierLoc(), diag::err_typecheck_no_member) 1619 << Name << D.getCXXScopeSpec().getRange(); 1620 InvalidDecl = true; 1621 } 1622 } 1623 return NewVD; 1624} 1625 1626NamedDecl* 1627Sema::ActOnFunctionDeclarator(Scope* S, Declarator& D, DeclContext* DC, 1628 QualType R, Decl *LastDeclarator, 1629 Decl* PrevDecl, bool IsFunctionDefinition, 1630 bool& InvalidDecl, bool &Redeclaration) { 1631 assert(R.getTypePtr()->isFunctionType()); 1632 1633 DeclarationName Name = GetNameForDeclarator(D); 1634 FunctionDecl::StorageClass SC = FunctionDecl::None; 1635 switch (D.getDeclSpec().getStorageClassSpec()) { 1636 default: assert(0 && "Unknown storage class!"); 1637 case DeclSpec::SCS_auto: 1638 case DeclSpec::SCS_register: 1639 case DeclSpec::SCS_mutable: 1640 Diag(D.getIdentifierLoc(), diag::err_typecheck_sclass_func); 1641 InvalidDecl = true; 1642 break; 1643 case DeclSpec::SCS_unspecified: SC = FunctionDecl::None; break; 1644 case DeclSpec::SCS_extern: SC = FunctionDecl::Extern; break; 1645 case DeclSpec::SCS_static: SC = FunctionDecl::Static; break; 1646 case DeclSpec::SCS_private_extern: SC = FunctionDecl::PrivateExtern;break; 1647 } 1648 1649 bool isInline = D.getDeclSpec().isInlineSpecified(); 1650 // bool isVirtual = D.getDeclSpec().isVirtualSpecified(); 1651 bool isExplicit = D.getDeclSpec().isExplicitSpecified(); 1652 1653 FunctionDecl *NewFD; 1654 if (D.getKind() == Declarator::DK_Constructor) { 1655 // This is a C++ constructor declaration. 1656 assert(DC->isRecord() && 1657 "Constructors can only be declared in a member context"); 1658 1659 InvalidDecl = InvalidDecl || CheckConstructorDeclarator(D, R, SC); 1660 1661 // Create the new declaration 1662 NewFD = CXXConstructorDecl::Create(Context, 1663 cast<CXXRecordDecl>(DC), 1664 D.getIdentifierLoc(), Name, R, 1665 isExplicit, isInline, 1666 /*isImplicitlyDeclared=*/false); 1667 1668 if (InvalidDecl) 1669 NewFD->setInvalidDecl(); 1670 } else if (D.getKind() == Declarator::DK_Destructor) { 1671 // This is a C++ destructor declaration. 1672 if (DC->isRecord()) { 1673 InvalidDecl = InvalidDecl || CheckDestructorDeclarator(D, R, SC); 1674 1675 NewFD = CXXDestructorDecl::Create(Context, 1676 cast<CXXRecordDecl>(DC), 1677 D.getIdentifierLoc(), Name, R, 1678 isInline, 1679 /*isImplicitlyDeclared=*/false); 1680 1681 if (InvalidDecl) 1682 NewFD->setInvalidDecl(); 1683 } else { 1684 Diag(D.getIdentifierLoc(), diag::err_destructor_not_member); 1685 1686 // Create a FunctionDecl to satisfy the function definition parsing 1687 // code path. 1688 NewFD = FunctionDecl::Create(Context, DC, D.getIdentifierLoc(), 1689 Name, R, SC, isInline, 1690 // FIXME: Move to DeclGroup... 1691 D.getDeclSpec().getSourceRange().getBegin()); 1692 InvalidDecl = true; 1693 NewFD->setInvalidDecl(); 1694 } 1695 } else if (D.getKind() == Declarator::DK_Conversion) { 1696 if (!DC->isRecord()) { 1697 Diag(D.getIdentifierLoc(), 1698 diag::err_conv_function_not_member); 1699 return 0; 1700 } else { 1701 InvalidDecl = InvalidDecl || CheckConversionDeclarator(D, R, SC); 1702 1703 NewFD = CXXConversionDecl::Create(Context, cast<CXXRecordDecl>(DC), 1704 D.getIdentifierLoc(), Name, R, 1705 isInline, isExplicit); 1706 1707 if (InvalidDecl) 1708 NewFD->setInvalidDecl(); 1709 } 1710 } else if (DC->isRecord()) { 1711 // This is a C++ method declaration. 1712 NewFD = CXXMethodDecl::Create(Context, cast<CXXRecordDecl>(DC), 1713 D.getIdentifierLoc(), Name, R, 1714 (SC == FunctionDecl::Static), isInline); 1715 } else { 1716 NewFD = FunctionDecl::Create(Context, DC, 1717 D.getIdentifierLoc(), 1718 Name, R, SC, isInline, 1719 // FIXME: Move to DeclGroup... 1720 D.getDeclSpec().getSourceRange().getBegin()); 1721 } 1722 NewFD->setNextDeclarator(LastDeclarator); 1723 1724 // Set the lexical context. If the declarator has a C++ 1725 // scope specifier, the lexical context will be different 1726 // from the semantic context. 1727 NewFD->setLexicalDeclContext(CurContext); 1728 1729 // Handle GNU asm-label extension (encoded as an attribute). 1730 if (Expr *E = (Expr*) D.getAsmLabel()) { 1731 // The parser guarantees this is a string. 1732 StringLiteral *SE = cast<StringLiteral>(E); 1733 NewFD->addAttr(new AsmLabelAttr(std::string(SE->getStrData(), 1734 SE->getByteLength()))); 1735 } 1736 1737 // Copy the parameter declarations from the declarator D to 1738 // the function declaration NewFD, if they are available. 1739 if (D.getNumTypeObjects() > 0) { 1740 DeclaratorChunk::FunctionTypeInfo &FTI = D.getTypeObject(0).Fun; 1741 1742 // Create Decl objects for each parameter, adding them to the 1743 // FunctionDecl. 1744 llvm::SmallVector<ParmVarDecl*, 16> Params; 1745 1746 // Check for C99 6.7.5.3p10 - foo(void) is a non-varargs 1747 // function that takes no arguments, not a function that takes a 1748 // single void argument. 1749 // We let through "const void" here because Sema::GetTypeForDeclarator 1750 // already checks for that case. 1751 if (FTI.NumArgs == 1 && !FTI.isVariadic && FTI.ArgInfo[0].Ident == 0 && 1752 FTI.ArgInfo[0].Param && 1753 ((ParmVarDecl*)FTI.ArgInfo[0].Param)->getType()->isVoidType()) { 1754 // empty arg list, don't push any params. 1755 ParmVarDecl *Param = (ParmVarDecl*)FTI.ArgInfo[0].Param; 1756 1757 // In C++, the empty parameter-type-list must be spelled "void"; a 1758 // typedef of void is not permitted. 1759 if (getLangOptions().CPlusPlus && 1760 Param->getType().getUnqualifiedType() != Context.VoidTy) { 1761 Diag(Param->getLocation(), diag::ext_param_typedef_of_void); 1762 } 1763 } else if (FTI.NumArgs > 0 && FTI.ArgInfo[0].Param != 0) { 1764 for (unsigned i = 0, e = FTI.NumArgs; i != e; ++i) 1765 Params.push_back((ParmVarDecl *)FTI.ArgInfo[i].Param); 1766 } 1767 1768 NewFD->setParams(Context, &Params[0], Params.size()); 1769 } else if (R->getAsTypedefType()) { 1770 // When we're declaring a function with a typedef, as in the 1771 // following example, we'll need to synthesize (unnamed) 1772 // parameters for use in the declaration. 1773 // 1774 // @code 1775 // typedef void fn(int); 1776 // fn f; 1777 // @endcode 1778 const FunctionTypeProto *FT = R->getAsFunctionTypeProto(); 1779 if (!FT) { 1780 // This is a typedef of a function with no prototype, so we 1781 // don't need to do anything. 1782 } else if ((FT->getNumArgs() == 0) || 1783 (FT->getNumArgs() == 1 && !FT->isVariadic() && 1784 FT->getArgType(0)->isVoidType())) { 1785 // This is a zero-argument function. We don't need to do anything. 1786 } else { 1787 // Synthesize a parameter for each argument type. 1788 llvm::SmallVector<ParmVarDecl*, 16> Params; 1789 for (FunctionTypeProto::arg_type_iterator ArgType = FT->arg_type_begin(); 1790 ArgType != FT->arg_type_end(); ++ArgType) { 1791 ParmVarDecl *Param = ParmVarDecl::Create(Context, DC, 1792 SourceLocation(), 0, 1793 *ArgType, VarDecl::None, 1794 0); 1795 Param->setImplicit(); 1796 Params.push_back(Param); 1797 } 1798 1799 NewFD->setParams(Context, &Params[0], Params.size()); 1800 } 1801 } 1802 1803 if (CXXConstructorDecl *Constructor = dyn_cast<CXXConstructorDecl>(NewFD)) 1804 InvalidDecl = InvalidDecl || CheckConstructor(Constructor); 1805 else if (isa<CXXDestructorDecl>(NewFD)) { 1806 CXXRecordDecl *Record = cast<CXXRecordDecl>(NewFD->getParent()); 1807 Record->setUserDeclaredDestructor(true); 1808 // C++ [class]p4: A POD-struct is an aggregate class that has [...] no 1809 // user-defined destructor. 1810 Record->setPOD(false); 1811 } else if (CXXConversionDecl *Conversion = 1812 dyn_cast<CXXConversionDecl>(NewFD)) 1813 ActOnConversionDeclarator(Conversion); 1814 1815 // Extra checking for C++ overloaded operators (C++ [over.oper]). 1816 if (NewFD->isOverloadedOperator() && 1817 CheckOverloadedOperatorDeclaration(NewFD)) 1818 NewFD->setInvalidDecl(); 1819 1820 // Merge the decl with the existing one if appropriate. Since C functions 1821 // are in a flat namespace, make sure we consider decls in outer scopes. 1822 bool OverloadableAttrRequired = false; 1823 if (PrevDecl && 1824 (!getLangOptions().CPlusPlus||isDeclInScope(PrevDecl, DC, S))) { 1825 // Determine whether NewFD is an overload of PrevDecl or 1826 // a declaration that requires merging. If it's an overload, 1827 // there's no more work to do here; we'll just add the new 1828 // function to the scope. 1829 OverloadedFunctionDecl::function_iterator MatchedDecl; 1830 1831 if (!getLangOptions().CPlusPlus && 1832 AllowOverloadingOfFunction(PrevDecl, Context)) { 1833 OverloadableAttrRequired = true; 1834 1835 // Functions marked "overloadable" must have a prototype (that 1836 // we can't get through declaration merging). 1837 if (!R->getAsFunctionTypeProto()) { 1838 Diag(NewFD->getLocation(), diag::err_attribute_overloadable_no_prototype) 1839 << NewFD; 1840 InvalidDecl = true; 1841 Redeclaration = true; 1842 1843 // Turn this into a variadic function with no parameters. 1844 R = Context.getFunctionType(R->getAsFunctionType()->getResultType(), 1845 0, 0, true, 0); 1846 NewFD->setType(R); 1847 } 1848 } 1849 1850 if (PrevDecl && 1851 (!AllowOverloadingOfFunction(PrevDecl, Context) || 1852 !IsOverload(NewFD, PrevDecl, MatchedDecl))) { 1853 Redeclaration = true; 1854 Decl *OldDecl = PrevDecl; 1855 1856 // If PrevDecl was an overloaded function, extract the 1857 // FunctionDecl that matched. 1858 if (isa<OverloadedFunctionDecl>(PrevDecl)) 1859 OldDecl = *MatchedDecl; 1860 1861 // NewFD and PrevDecl represent declarations that need to be 1862 // merged. 1863 if (MergeFunctionDecl(NewFD, OldDecl)) 1864 InvalidDecl = true; 1865 1866 if (!InvalidDecl) { 1867 NewFD->setPreviousDeclaration(cast<FunctionDecl>(OldDecl)); 1868 1869 // An out-of-line member function declaration must also be a 1870 // definition (C++ [dcl.meaning]p1). 1871 if (!IsFunctionDefinition && D.getCXXScopeSpec().isSet() && 1872 !InvalidDecl) { 1873 Diag(NewFD->getLocation(), diag::err_out_of_line_declaration) 1874 << D.getCXXScopeSpec().getRange(); 1875 NewFD->setInvalidDecl(); 1876 } 1877 } 1878 } 1879 } 1880 1881 if (D.getCXXScopeSpec().isSet() && 1882 (!PrevDecl || !Redeclaration)) { 1883 // The user tried to provide an out-of-line definition for a 1884 // function that is a member of a class or namespace, but there 1885 // was no such member function declared (C++ [class.mfct]p2, 1886 // C++ [namespace.memdef]p2). For example: 1887 // 1888 // class X { 1889 // void f() const; 1890 // }; 1891 // 1892 // void X::f() { } // ill-formed 1893 // 1894 // Complain about this problem, and attempt to suggest close 1895 // matches (e.g., those that differ only in cv-qualifiers and 1896 // whether the parameter types are references). 1897 Diag(D.getIdentifierLoc(), diag::err_member_def_does_not_match) 1898 << cast<NamedDecl>(DC) << D.getCXXScopeSpec().getRange(); 1899 InvalidDecl = true; 1900 1901 LookupResult Prev = LookupQualifiedName(DC, Name, LookupOrdinaryName, 1902 true); 1903 assert(!Prev.isAmbiguous() && 1904 "Cannot have an ambiguity in previous-declaration lookup"); 1905 for (LookupResult::iterator Func = Prev.begin(), FuncEnd = Prev.end(); 1906 Func != FuncEnd; ++Func) { 1907 if (isa<FunctionDecl>(*Func) && 1908 isNearlyMatchingFunction(Context, cast<FunctionDecl>(*Func), NewFD)) 1909 Diag((*Func)->getLocation(), diag::note_member_def_close_match); 1910 } 1911 1912 PrevDecl = 0; 1913 } 1914 1915 // Handle attributes. We need to have merged decls when handling attributes 1916 // (for example to check for conflicts, etc). 1917 ProcessDeclAttributes(NewFD, D); 1918 AddKnownFunctionAttributes(NewFD); 1919 1920 if (OverloadableAttrRequired && !NewFD->getAttr<OverloadableAttr>()) { 1921 // If a function name is overloadable in C, then every function 1922 // with that name must be marked "overloadable". 1923 Diag(NewFD->getLocation(), diag::err_attribute_overloadable_missing) 1924 << Redeclaration << NewFD; 1925 if (PrevDecl) 1926 Diag(PrevDecl->getLocation(), 1927 diag::note_attribute_overloadable_prev_overload); 1928 NewFD->addAttr(new OverloadableAttr); 1929 } 1930 1931 if (getLangOptions().CPlusPlus) { 1932 // In C++, check default arguments now that we have merged decls. Unless 1933 // the lexical context is the class, because in this case this is done 1934 // during delayed parsing anyway. 1935 if (!CurContext->isRecord()) 1936 CheckCXXDefaultArguments(NewFD); 1937 1938 // An out-of-line member function declaration must also be a 1939 // definition (C++ [dcl.meaning]p1). 1940 if (!IsFunctionDefinition && D.getCXXScopeSpec().isSet() && !InvalidDecl) { 1941 Diag(NewFD->getLocation(), diag::err_out_of_line_declaration) 1942 << D.getCXXScopeSpec().getRange(); 1943 InvalidDecl = true; 1944 } 1945 } 1946 return NewFD; 1947} 1948 1949void Sema::InitializerElementNotConstant(const Expr *Init) { 1950 Diag(Init->getExprLoc(), diag::err_init_element_not_constant) 1951 << Init->getSourceRange(); 1952} 1953 1954bool Sema::CheckAddressConstantExpressionLValue(const Expr* Init) { 1955 switch (Init->getStmtClass()) { 1956 default: 1957 InitializerElementNotConstant(Init); 1958 return true; 1959 case Expr::ParenExprClass: { 1960 const ParenExpr* PE = cast<ParenExpr>(Init); 1961 return CheckAddressConstantExpressionLValue(PE->getSubExpr()); 1962 } 1963 case Expr::CompoundLiteralExprClass: 1964 return cast<CompoundLiteralExpr>(Init)->isFileScope(); 1965 case Expr::DeclRefExprClass: 1966 case Expr::QualifiedDeclRefExprClass: { 1967 const Decl *D = cast<DeclRefExpr>(Init)->getDecl(); 1968 if (const VarDecl *VD = dyn_cast<VarDecl>(D)) { 1969 if (VD->hasGlobalStorage()) 1970 return false; 1971 InitializerElementNotConstant(Init); 1972 return true; 1973 } 1974 if (isa<FunctionDecl>(D)) 1975 return false; 1976 InitializerElementNotConstant(Init); 1977 return true; 1978 } 1979 case Expr::MemberExprClass: { 1980 const MemberExpr *M = cast<MemberExpr>(Init); 1981 if (M->isArrow()) 1982 return CheckAddressConstantExpression(M->getBase()); 1983 return CheckAddressConstantExpressionLValue(M->getBase()); 1984 } 1985 case Expr::ArraySubscriptExprClass: { 1986 // FIXME: Should we pedwarn for "x[0+0]" (where x is a pointer)? 1987 const ArraySubscriptExpr *ASE = cast<ArraySubscriptExpr>(Init); 1988 return CheckAddressConstantExpression(ASE->getBase()) || 1989 CheckArithmeticConstantExpression(ASE->getIdx()); 1990 } 1991 case Expr::StringLiteralClass: 1992 case Expr::PredefinedExprClass: 1993 return false; 1994 case Expr::UnaryOperatorClass: { 1995 const UnaryOperator *Exp = cast<UnaryOperator>(Init); 1996 1997 // C99 6.6p9 1998 if (Exp->getOpcode() == UnaryOperator::Deref) 1999 return CheckAddressConstantExpression(Exp->getSubExpr()); 2000 2001 InitializerElementNotConstant(Init); 2002 return true; 2003 } 2004 } 2005} 2006 2007bool Sema::CheckAddressConstantExpression(const Expr* Init) { 2008 switch (Init->getStmtClass()) { 2009 default: 2010 InitializerElementNotConstant(Init); 2011 return true; 2012 case Expr::ParenExprClass: 2013 return CheckAddressConstantExpression(cast<ParenExpr>(Init)->getSubExpr()); 2014 case Expr::StringLiteralClass: 2015 case Expr::ObjCStringLiteralClass: 2016 return false; 2017 case Expr::CallExprClass: 2018 case Expr::CXXOperatorCallExprClass: 2019 // __builtin___CFStringMakeConstantString is a valid constant l-value. 2020 if (cast<CallExpr>(Init)->isBuiltinCall(Context) == 2021 Builtin::BI__builtin___CFStringMakeConstantString) 2022 return false; 2023 2024 InitializerElementNotConstant(Init); 2025 return true; 2026 2027 case Expr::UnaryOperatorClass: { 2028 const UnaryOperator *Exp = cast<UnaryOperator>(Init); 2029 2030 // C99 6.6p9 2031 if (Exp->getOpcode() == UnaryOperator::AddrOf) 2032 return CheckAddressConstantExpressionLValue(Exp->getSubExpr()); 2033 2034 if (Exp->getOpcode() == UnaryOperator::Extension) 2035 return CheckAddressConstantExpression(Exp->getSubExpr()); 2036 2037 InitializerElementNotConstant(Init); 2038 return true; 2039 } 2040 case Expr::BinaryOperatorClass: { 2041 // FIXME: Should we pedwarn for expressions like "a + 1 + 2"? 2042 const BinaryOperator *Exp = cast<BinaryOperator>(Init); 2043 2044 Expr *PExp = Exp->getLHS(); 2045 Expr *IExp = Exp->getRHS(); 2046 if (IExp->getType()->isPointerType()) 2047 std::swap(PExp, IExp); 2048 2049 // FIXME: Should we pedwarn if IExp isn't an integer constant expression? 2050 return CheckAddressConstantExpression(PExp) || 2051 CheckArithmeticConstantExpression(IExp); 2052 } 2053 case Expr::ImplicitCastExprClass: 2054 case Expr::CStyleCastExprClass: { 2055 const Expr* SubExpr = cast<CastExpr>(Init)->getSubExpr(); 2056 if (Init->getStmtClass() == Expr::ImplicitCastExprClass) { 2057 // Check for implicit promotion 2058 if (SubExpr->getType()->isFunctionType() || 2059 SubExpr->getType()->isArrayType()) 2060 return CheckAddressConstantExpressionLValue(SubExpr); 2061 } 2062 2063 // Check for pointer->pointer cast 2064 if (SubExpr->getType()->isPointerType()) 2065 return CheckAddressConstantExpression(SubExpr); 2066 2067 if (SubExpr->getType()->isIntegralType()) { 2068 // Check for the special-case of a pointer->int->pointer cast; 2069 // this isn't standard, but some code requires it. See 2070 // PR2720 for an example. 2071 if (const CastExpr* SubCast = dyn_cast<CastExpr>(SubExpr)) { 2072 if (SubCast->getSubExpr()->getType()->isPointerType()) { 2073 unsigned IntWidth = Context.getIntWidth(SubCast->getType()); 2074 unsigned PointerWidth = Context.getTypeSize(Context.VoidPtrTy); 2075 if (IntWidth >= PointerWidth) { 2076 return CheckAddressConstantExpression(SubCast->getSubExpr()); 2077 } 2078 } 2079 } 2080 } 2081 if (SubExpr->getType()->isArithmeticType()) { 2082 return CheckArithmeticConstantExpression(SubExpr); 2083 } 2084 2085 InitializerElementNotConstant(Init); 2086 return true; 2087 } 2088 case Expr::ConditionalOperatorClass: { 2089 // FIXME: Should we pedwarn here? 2090 const ConditionalOperator *Exp = cast<ConditionalOperator>(Init); 2091 if (!Exp->getCond()->getType()->isArithmeticType()) { 2092 InitializerElementNotConstant(Init); 2093 return true; 2094 } 2095 if (CheckArithmeticConstantExpression(Exp->getCond())) 2096 return true; 2097 if (Exp->getLHS() && 2098 CheckAddressConstantExpression(Exp->getLHS())) 2099 return true; 2100 return CheckAddressConstantExpression(Exp->getRHS()); 2101 } 2102 case Expr::AddrLabelExprClass: 2103 return false; 2104 } 2105} 2106 2107static const Expr* FindExpressionBaseAddress(const Expr* E); 2108 2109static const Expr* FindExpressionBaseAddressLValue(const Expr* E) { 2110 switch (E->getStmtClass()) { 2111 default: 2112 return E; 2113 case Expr::ParenExprClass: { 2114 const ParenExpr* PE = cast<ParenExpr>(E); 2115 return FindExpressionBaseAddressLValue(PE->getSubExpr()); 2116 } 2117 case Expr::MemberExprClass: { 2118 const MemberExpr *M = cast<MemberExpr>(E); 2119 if (M->isArrow()) 2120 return FindExpressionBaseAddress(M->getBase()); 2121 return FindExpressionBaseAddressLValue(M->getBase()); 2122 } 2123 case Expr::ArraySubscriptExprClass: { 2124 const ArraySubscriptExpr *ASE = cast<ArraySubscriptExpr>(E); 2125 return FindExpressionBaseAddress(ASE->getBase()); 2126 } 2127 case Expr::UnaryOperatorClass: { 2128 const UnaryOperator *Exp = cast<UnaryOperator>(E); 2129 2130 if (Exp->getOpcode() == UnaryOperator::Deref) 2131 return FindExpressionBaseAddress(Exp->getSubExpr()); 2132 2133 return E; 2134 } 2135 } 2136} 2137 2138static const Expr* FindExpressionBaseAddress(const Expr* E) { 2139 switch (E->getStmtClass()) { 2140 default: 2141 return E; 2142 case Expr::ParenExprClass: { 2143 const ParenExpr* PE = cast<ParenExpr>(E); 2144 return FindExpressionBaseAddress(PE->getSubExpr()); 2145 } 2146 case Expr::UnaryOperatorClass: { 2147 const UnaryOperator *Exp = cast<UnaryOperator>(E); 2148 2149 // C99 6.6p9 2150 if (Exp->getOpcode() == UnaryOperator::AddrOf) 2151 return FindExpressionBaseAddressLValue(Exp->getSubExpr()); 2152 2153 if (Exp->getOpcode() == UnaryOperator::Extension) 2154 return FindExpressionBaseAddress(Exp->getSubExpr()); 2155 2156 return E; 2157 } 2158 case Expr::BinaryOperatorClass: { 2159 const BinaryOperator *Exp = cast<BinaryOperator>(E); 2160 2161 Expr *PExp = Exp->getLHS(); 2162 Expr *IExp = Exp->getRHS(); 2163 if (IExp->getType()->isPointerType()) 2164 std::swap(PExp, IExp); 2165 2166 return FindExpressionBaseAddress(PExp); 2167 } 2168 case Expr::ImplicitCastExprClass: { 2169 const Expr* SubExpr = cast<ImplicitCastExpr>(E)->getSubExpr(); 2170 2171 // Check for implicit promotion 2172 if (SubExpr->getType()->isFunctionType() || 2173 SubExpr->getType()->isArrayType()) 2174 return FindExpressionBaseAddressLValue(SubExpr); 2175 2176 // Check for pointer->pointer cast 2177 if (SubExpr->getType()->isPointerType()) 2178 return FindExpressionBaseAddress(SubExpr); 2179 2180 // We assume that we have an arithmetic expression here; 2181 // if we don't, we'll figure it out later 2182 return 0; 2183 } 2184 case Expr::CStyleCastExprClass: { 2185 const Expr* SubExpr = cast<CastExpr>(E)->getSubExpr(); 2186 2187 // Check for pointer->pointer cast 2188 if (SubExpr->getType()->isPointerType()) 2189 return FindExpressionBaseAddress(SubExpr); 2190 2191 // We assume that we have an arithmetic expression here; 2192 // if we don't, we'll figure it out later 2193 return 0; 2194 } 2195 } 2196} 2197 2198bool Sema::CheckArithmeticConstantExpression(const Expr* Init) { 2199 switch (Init->getStmtClass()) { 2200 default: 2201 InitializerElementNotConstant(Init); 2202 return true; 2203 case Expr::ParenExprClass: { 2204 const ParenExpr* PE = cast<ParenExpr>(Init); 2205 return CheckArithmeticConstantExpression(PE->getSubExpr()); 2206 } 2207 case Expr::FloatingLiteralClass: 2208 case Expr::IntegerLiteralClass: 2209 case Expr::CharacterLiteralClass: 2210 case Expr::ImaginaryLiteralClass: 2211 case Expr::TypesCompatibleExprClass: 2212 case Expr::CXXBoolLiteralExprClass: 2213 return false; 2214 case Expr::CallExprClass: 2215 case Expr::CXXOperatorCallExprClass: { 2216 const CallExpr *CE = cast<CallExpr>(Init); 2217 2218 // Allow any constant foldable calls to builtins. 2219 if (CE->isBuiltinCall(Context) && CE->isEvaluatable(Context)) 2220 return false; 2221 2222 InitializerElementNotConstant(Init); 2223 return true; 2224 } 2225 case Expr::DeclRefExprClass: 2226 case Expr::QualifiedDeclRefExprClass: { 2227 const Decl *D = cast<DeclRefExpr>(Init)->getDecl(); 2228 if (isa<EnumConstantDecl>(D)) 2229 return false; 2230 InitializerElementNotConstant(Init); 2231 return true; 2232 } 2233 case Expr::CompoundLiteralExprClass: 2234 // Allow "(vector type){2,4}"; normal C constraints don't allow this, 2235 // but vectors are allowed to be magic. 2236 if (Init->getType()->isVectorType()) 2237 return false; 2238 InitializerElementNotConstant(Init); 2239 return true; 2240 case Expr::UnaryOperatorClass: { 2241 const UnaryOperator *Exp = cast<UnaryOperator>(Init); 2242 2243 switch (Exp->getOpcode()) { 2244 // Address, indirect, pre/post inc/dec, etc are not valid constant exprs. 2245 // See C99 6.6p3. 2246 default: 2247 InitializerElementNotConstant(Init); 2248 return true; 2249 case UnaryOperator::OffsetOf: 2250 if (Exp->getSubExpr()->getType()->isConstantSizeType()) 2251 return false; 2252 InitializerElementNotConstant(Init); 2253 return true; 2254 case UnaryOperator::Extension: 2255 case UnaryOperator::LNot: 2256 case UnaryOperator::Plus: 2257 case UnaryOperator::Minus: 2258 case UnaryOperator::Not: 2259 return CheckArithmeticConstantExpression(Exp->getSubExpr()); 2260 } 2261 } 2262 case Expr::SizeOfAlignOfExprClass: { 2263 const SizeOfAlignOfExpr *Exp = cast<SizeOfAlignOfExpr>(Init); 2264 // Special check for void types, which are allowed as an extension 2265 if (Exp->getTypeOfArgument()->isVoidType()) 2266 return false; 2267 // alignof always evaluates to a constant. 2268 // FIXME: is sizeof(int[3.0]) a constant expression? 2269 if (Exp->isSizeOf() && !Exp->getTypeOfArgument()->isConstantSizeType()) { 2270 InitializerElementNotConstant(Init); 2271 return true; 2272 } 2273 return false; 2274 } 2275 case Expr::BinaryOperatorClass: { 2276 const BinaryOperator *Exp = cast<BinaryOperator>(Init); 2277 2278 if (Exp->getLHS()->getType()->isArithmeticType() && 2279 Exp->getRHS()->getType()->isArithmeticType()) { 2280 return CheckArithmeticConstantExpression(Exp->getLHS()) || 2281 CheckArithmeticConstantExpression(Exp->getRHS()); 2282 } 2283 2284 if (Exp->getLHS()->getType()->isPointerType() && 2285 Exp->getRHS()->getType()->isPointerType()) { 2286 const Expr* LHSBase = FindExpressionBaseAddress(Exp->getLHS()); 2287 const Expr* RHSBase = FindExpressionBaseAddress(Exp->getRHS()); 2288 2289 // Only allow a null (constant integer) base; we could 2290 // allow some additional cases if necessary, but this 2291 // is sufficient to cover offsetof-like constructs. 2292 if (!LHSBase && !RHSBase) { 2293 return CheckAddressConstantExpression(Exp->getLHS()) || 2294 CheckAddressConstantExpression(Exp->getRHS()); 2295 } 2296 } 2297 2298 InitializerElementNotConstant(Init); 2299 return true; 2300 } 2301 case Expr::ImplicitCastExprClass: 2302 case Expr::CStyleCastExprClass: { 2303 const CastExpr *CE = cast<CastExpr>(Init); 2304 const Expr *SubExpr = CE->getSubExpr(); 2305 2306 if (SubExpr->getType()->isArithmeticType()) 2307 return CheckArithmeticConstantExpression(SubExpr); 2308 2309 if (SubExpr->getType()->isPointerType()) { 2310 const Expr* Base = FindExpressionBaseAddress(SubExpr); 2311 if (Base) { 2312 // the cast is only valid if done to a wide enough type 2313 if (Context.getTypeSize(CE->getType()) >= 2314 Context.getTypeSize(SubExpr->getType())) 2315 return false; 2316 } else { 2317 // If the pointer has a null base, this is an offsetof-like construct 2318 return CheckAddressConstantExpression(SubExpr); 2319 } 2320 } 2321 2322 InitializerElementNotConstant(Init); 2323 return true; 2324 } 2325 case Expr::ConditionalOperatorClass: { 2326 const ConditionalOperator *Exp = cast<ConditionalOperator>(Init); 2327 2328 // If GNU extensions are disabled, we require all operands to be arithmetic 2329 // constant expressions. 2330 if (getLangOptions().NoExtensions) { 2331 return CheckArithmeticConstantExpression(Exp->getCond()) || 2332 (Exp->getLHS() && CheckArithmeticConstantExpression(Exp->getLHS())) || 2333 CheckArithmeticConstantExpression(Exp->getRHS()); 2334 } 2335 2336 // Otherwise, we have to emulate some of the behavior of fold here. 2337 // Basically GCC treats things like "4 ? 1 : somefunc()" as a constant 2338 // because it can constant fold things away. To retain compatibility with 2339 // GCC code, we see if we can fold the condition to a constant (which we 2340 // should always be able to do in theory). If so, we only require the 2341 // specified arm of the conditional to be a constant. This is a horrible 2342 // hack, but is require by real world code that uses __builtin_constant_p. 2343 Expr::EvalResult EvalResult; 2344 if (!Exp->getCond()->Evaluate(EvalResult, Context) || 2345 EvalResult.HasSideEffects) { 2346 // If Evaluate couldn't fold it, CheckArithmeticConstantExpression 2347 // won't be able to either. Use it to emit the diagnostic though. 2348 bool Res = CheckArithmeticConstantExpression(Exp->getCond()); 2349 assert(Res && "Evaluate couldn't evaluate this constant?"); 2350 return Res; 2351 } 2352 2353 // Verify that the side following the condition is also a constant. 2354 const Expr *TrueSide = Exp->getLHS(), *FalseSide = Exp->getRHS(); 2355 if (EvalResult.Val.getInt() == 0) 2356 std::swap(TrueSide, FalseSide); 2357 2358 if (TrueSide && CheckArithmeticConstantExpression(TrueSide)) 2359 return true; 2360 2361 // Okay, the evaluated side evaluates to a constant, so we accept this. 2362 // Check to see if the other side is obviously not a constant. If so, 2363 // emit a warning that this is a GNU extension. 2364 if (FalseSide && !FalseSide->isEvaluatable(Context)) 2365 Diag(Init->getExprLoc(), 2366 diag::ext_typecheck_expression_not_constant_but_accepted) 2367 << FalseSide->getSourceRange(); 2368 return false; 2369 } 2370 } 2371} 2372 2373bool Sema::CheckForConstantInitializer(Expr *Init, QualType DclT) { 2374 if (DesignatedInitExpr *DIE = dyn_cast<DesignatedInitExpr>(Init)) 2375 Init = DIE->getInit(); 2376 2377 Init = Init->IgnoreParens(); 2378 2379 if (Init->isEvaluatable(Context)) 2380 return false; 2381 2382 // Look through CXXDefaultArgExprs; they have no meaning in this context. 2383 if (CXXDefaultArgExpr* DAE = dyn_cast<CXXDefaultArgExpr>(Init)) 2384 return CheckForConstantInitializer(DAE->getExpr(), DclT); 2385 2386 if (CompoundLiteralExpr *e = dyn_cast<CompoundLiteralExpr>(Init)) 2387 return CheckForConstantInitializer(e->getInitializer(), DclT); 2388 2389 if (isa<ImplicitValueInitExpr>(Init)) { 2390 // FIXME: In C++, check for non-POD types. 2391 return false; 2392 } 2393 2394 if (InitListExpr *Exp = dyn_cast<InitListExpr>(Init)) { 2395 unsigned numInits = Exp->getNumInits(); 2396 for (unsigned i = 0; i < numInits; i++) { 2397 // FIXME: Need to get the type of the declaration for C++, 2398 // because it could be a reference? 2399 2400 if (CheckForConstantInitializer(Exp->getInit(i), 2401 Exp->getInit(i)->getType())) 2402 return true; 2403 } 2404 return false; 2405 } 2406 2407 // FIXME: We can probably remove some of this code below, now that 2408 // Expr::Evaluate is doing the heavy lifting for scalars. 2409 2410 if (Init->isNullPointerConstant(Context)) 2411 return false; 2412 if (Init->getType()->isArithmeticType()) { 2413 QualType InitTy = Context.getCanonicalType(Init->getType()) 2414 .getUnqualifiedType(); 2415 if (InitTy == Context.BoolTy) { 2416 // Special handling for pointers implicitly cast to bool; 2417 // (e.g. "_Bool rr = &rr;"). This is only legal at the top level. 2418 if (ImplicitCastExpr* ICE = dyn_cast<ImplicitCastExpr>(Init)) { 2419 Expr* SubE = ICE->getSubExpr(); 2420 if (SubE->getType()->isPointerType() || 2421 SubE->getType()->isArrayType() || 2422 SubE->getType()->isFunctionType()) { 2423 return CheckAddressConstantExpression(Init); 2424 } 2425 } 2426 } else if (InitTy->isIntegralType()) { 2427 Expr* SubE = 0; 2428 if (CastExpr* CE = dyn_cast<CastExpr>(Init)) 2429 SubE = CE->getSubExpr(); 2430 // Special check for pointer cast to int; we allow as an extension 2431 // an address constant cast to an integer if the integer 2432 // is of an appropriate width (this sort of code is apparently used 2433 // in some places). 2434 // FIXME: Add pedwarn? 2435 // FIXME: Don't allow bitfields here! Need the FieldDecl for that. 2436 if (SubE && (SubE->getType()->isPointerType() || 2437 SubE->getType()->isArrayType() || 2438 SubE->getType()->isFunctionType())) { 2439 unsigned IntWidth = Context.getTypeSize(Init->getType()); 2440 unsigned PointerWidth = Context.getTypeSize(Context.VoidPtrTy); 2441 if (IntWidth >= PointerWidth) 2442 return CheckAddressConstantExpression(Init); 2443 } 2444 } 2445 2446 return CheckArithmeticConstantExpression(Init); 2447 } 2448 2449 if (Init->getType()->isPointerType()) 2450 return CheckAddressConstantExpression(Init); 2451 2452 // An array type at the top level that isn't an init-list must 2453 // be a string literal 2454 if (Init->getType()->isArrayType()) 2455 return false; 2456 2457 if (Init->getType()->isFunctionType()) 2458 return false; 2459 2460 // Allow block exprs at top level. 2461 if (Init->getType()->isBlockPointerType()) 2462 return false; 2463 2464 // GCC cast to union extension 2465 // note: the validity of the cast expr is checked by CheckCastTypes() 2466 if (CastExpr *C = dyn_cast<CastExpr>(Init)) { 2467 QualType T = C->getType(); 2468 return T->isUnionType() && CheckForConstantInitializer(C->getSubExpr(), T); 2469 } 2470 2471 InitializerElementNotConstant(Init); 2472 return true; 2473} 2474 2475void Sema::AddInitializerToDecl(DeclTy *dcl, ExprArg init) { 2476 AddInitializerToDecl(dcl, move(init), /*DirectInit=*/false); 2477} 2478 2479/// AddInitializerToDecl - Adds the initializer Init to the 2480/// declaration dcl. If DirectInit is true, this is C++ direct 2481/// initialization rather than copy initialization. 2482void Sema::AddInitializerToDecl(DeclTy *dcl, ExprArg init, bool DirectInit) { 2483 Decl *RealDecl = static_cast<Decl *>(dcl); 2484 Expr *Init = static_cast<Expr *>(init.release()); 2485 assert(Init && "missing initializer"); 2486 2487 // If there is no declaration, there was an error parsing it. Just ignore 2488 // the initializer. 2489 if (RealDecl == 0) { 2490 Init->Destroy(Context); 2491 return; 2492 } 2493 2494 VarDecl *VDecl = dyn_cast<VarDecl>(RealDecl); 2495 if (!VDecl) { 2496 Diag(RealDecl->getLocation(), diag::err_illegal_initializer); 2497 RealDecl->setInvalidDecl(); 2498 return; 2499 } 2500 // Get the decls type and save a reference for later, since 2501 // CheckInitializerTypes may change it. 2502 QualType DclT = VDecl->getType(), SavT = DclT; 2503 if (VDecl->isBlockVarDecl()) { 2504 VarDecl::StorageClass SC = VDecl->getStorageClass(); 2505 if (SC == VarDecl::Extern) { // C99 6.7.8p5 2506 Diag(VDecl->getLocation(), diag::err_block_extern_cant_init); 2507 VDecl->setInvalidDecl(); 2508 } else if (!VDecl->isInvalidDecl()) { 2509 if (CheckInitializerTypes(Init, DclT, VDecl->getLocation(), 2510 VDecl->getDeclName(), DirectInit)) 2511 VDecl->setInvalidDecl(); 2512 2513 // C++ 3.6.2p2, allow dynamic initialization of static initializers. 2514 // Don't check invalid declarations to avoid emitting useless diagnostics. 2515 if (!getLangOptions().CPlusPlus && !VDecl->isInvalidDecl()) { 2516 if (SC == VarDecl::Static) // C99 6.7.8p4. 2517 CheckForConstantInitializer(Init, DclT); 2518 } 2519 } 2520 } else if (VDecl->isFileVarDecl()) { 2521 if (VDecl->getStorageClass() == VarDecl::Extern) 2522 Diag(VDecl->getLocation(), diag::warn_extern_init); 2523 if (!VDecl->isInvalidDecl()) 2524 if (CheckInitializerTypes(Init, DclT, VDecl->getLocation(), 2525 VDecl->getDeclName(), DirectInit)) 2526 VDecl->setInvalidDecl(); 2527 2528 // C++ 3.6.2p2, allow dynamic initialization of static initializers. 2529 // Don't check invalid declarations to avoid emitting useless diagnostics. 2530 if (!getLangOptions().CPlusPlus && !VDecl->isInvalidDecl()) { 2531 // C99 6.7.8p4. All file scoped initializers need to be constant. 2532 CheckForConstantInitializer(Init, DclT); 2533 } 2534 } 2535 // If the type changed, it means we had an incomplete type that was 2536 // completed by the initializer. For example: 2537 // int ary[] = { 1, 3, 5 }; 2538 // "ary" transitions from a VariableArrayType to a ConstantArrayType. 2539 if (!VDecl->isInvalidDecl() && (DclT != SavT)) { 2540 VDecl->setType(DclT); 2541 Init->setType(DclT); 2542 } 2543 2544 // Attach the initializer to the decl. 2545 VDecl->setInit(Init); 2546 return; 2547} 2548 2549void Sema::ActOnUninitializedDecl(DeclTy *dcl) { 2550 Decl *RealDecl = static_cast<Decl *>(dcl); 2551 2552 // If there is no declaration, there was an error parsing it. Just ignore it. 2553 if (RealDecl == 0) 2554 return; 2555 2556 if (VarDecl *Var = dyn_cast<VarDecl>(RealDecl)) { 2557 QualType Type = Var->getType(); 2558 // C++ [dcl.init.ref]p3: 2559 // The initializer can be omitted for a reference only in a 2560 // parameter declaration (8.3.5), in the declaration of a 2561 // function return type, in the declaration of a class member 2562 // within its class declaration (9.2), and where the extern 2563 // specifier is explicitly used. 2564 if (Type->isReferenceType() && 2565 Var->getStorageClass() != VarDecl::Extern && 2566 Var->getStorageClass() != VarDecl::PrivateExtern) { 2567 Diag(Var->getLocation(), diag::err_reference_var_requires_init) 2568 << Var->getDeclName() 2569 << SourceRange(Var->getLocation(), Var->getLocation()); 2570 Var->setInvalidDecl(); 2571 return; 2572 } 2573 2574 // C++ [dcl.init]p9: 2575 // 2576 // If no initializer is specified for an object, and the object 2577 // is of (possibly cv-qualified) non-POD class type (or array 2578 // thereof), the object shall be default-initialized; if the 2579 // object is of const-qualified type, the underlying class type 2580 // shall have a user-declared default constructor. 2581 if (getLangOptions().CPlusPlus) { 2582 QualType InitType = Type; 2583 if (const ArrayType *Array = Context.getAsArrayType(Type)) 2584 InitType = Array->getElementType(); 2585 if (Var->getStorageClass() != VarDecl::Extern && 2586 Var->getStorageClass() != VarDecl::PrivateExtern && 2587 InitType->isRecordType()) { 2588 const CXXConstructorDecl *Constructor 2589 = PerformInitializationByConstructor(InitType, 0, 0, 2590 Var->getLocation(), 2591 SourceRange(Var->getLocation(), 2592 Var->getLocation()), 2593 Var->getDeclName(), 2594 IK_Default); 2595 if (!Constructor) 2596 Var->setInvalidDecl(); 2597 } 2598 } 2599 2600#if 0 2601 // FIXME: Temporarily disabled because we are not properly parsing 2602 // linkage specifications on declarations, e.g., 2603 // 2604 // extern "C" const CGPoint CGPointerZero; 2605 // 2606 // C++ [dcl.init]p9: 2607 // 2608 // If no initializer is specified for an object, and the 2609 // object is of (possibly cv-qualified) non-POD class type (or 2610 // array thereof), the object shall be default-initialized; if 2611 // the object is of const-qualified type, the underlying class 2612 // type shall have a user-declared default 2613 // constructor. Otherwise, if no initializer is specified for 2614 // an object, the object and its subobjects, if any, have an 2615 // indeterminate initial value; if the object or any of its 2616 // subobjects are of const-qualified type, the program is 2617 // ill-formed. 2618 // 2619 // This isn't technically an error in C, so we don't diagnose it. 2620 // 2621 // FIXME: Actually perform the POD/user-defined default 2622 // constructor check. 2623 if (getLangOptions().CPlusPlus && 2624 Context.getCanonicalType(Type).isConstQualified() && 2625 Var->getStorageClass() != VarDecl::Extern) 2626 Diag(Var->getLocation(), diag::err_const_var_requires_init) 2627 << Var->getName() 2628 << SourceRange(Var->getLocation(), Var->getLocation()); 2629#endif 2630 } 2631} 2632 2633/// The declarators are chained together backwards, reverse the list. 2634Sema::DeclTy *Sema::FinalizeDeclaratorGroup(Scope *S, DeclTy *group) { 2635 // Often we have single declarators, handle them quickly. 2636 Decl *Group = static_cast<Decl*>(group); 2637 if (Group == 0) 2638 return 0; 2639 2640 Decl *NewGroup = 0; 2641 if (Group->getNextDeclarator() == 0) 2642 NewGroup = Group; 2643 else { // reverse the list. 2644 while (Group) { 2645 Decl *Next = Group->getNextDeclarator(); 2646 Group->setNextDeclarator(NewGroup); 2647 NewGroup = Group; 2648 Group = Next; 2649 } 2650 } 2651 // Perform semantic analysis that depends on having fully processed both 2652 // the declarator and initializer. 2653 for (Decl *ID = NewGroup; ID; ID = ID->getNextDeclarator()) { 2654 VarDecl *IDecl = dyn_cast<VarDecl>(ID); 2655 if (!IDecl) 2656 continue; 2657 QualType T = IDecl->getType(); 2658 2659 if (T->isVariableArrayType()) { 2660 const VariableArrayType *VAT = Context.getAsVariableArrayType(T); 2661 2662 // FIXME: This won't give the correct result for 2663 // int a[10][n]; 2664 SourceRange SizeRange = VAT->getSizeExpr()->getSourceRange(); 2665 if (IDecl->isFileVarDecl()) { 2666 Diag(IDecl->getLocation(), diag::err_vla_decl_in_file_scope) << 2667 SizeRange; 2668 2669 IDecl->setInvalidDecl(); 2670 } else { 2671 // C99 6.7.5.2p2: If an identifier is declared to be an object with 2672 // static storage duration, it shall not have a variable length array. 2673 if (IDecl->getStorageClass() == VarDecl::Static) { 2674 Diag(IDecl->getLocation(), diag::err_vla_decl_has_static_storage) 2675 << SizeRange; 2676 IDecl->setInvalidDecl(); 2677 } else if (IDecl->getStorageClass() == VarDecl::Extern) { 2678 Diag(IDecl->getLocation(), diag::err_vla_decl_has_extern_linkage) 2679 << SizeRange; 2680 IDecl->setInvalidDecl(); 2681 } 2682 } 2683 } else if (T->isVariablyModifiedType()) { 2684 if (IDecl->isFileVarDecl()) { 2685 Diag(IDecl->getLocation(), diag::err_vm_decl_in_file_scope); 2686 IDecl->setInvalidDecl(); 2687 } else { 2688 if (IDecl->getStorageClass() == VarDecl::Extern) { 2689 Diag(IDecl->getLocation(), diag::err_vm_decl_has_extern_linkage); 2690 IDecl->setInvalidDecl(); 2691 } 2692 } 2693 } 2694 2695 // Block scope. C99 6.7p7: If an identifier for an object is declared with 2696 // no linkage (C99 6.2.2p6), the type for the object shall be complete... 2697 if (IDecl->isBlockVarDecl() && 2698 IDecl->getStorageClass() != VarDecl::Extern) { 2699 if (!IDecl->isInvalidDecl() && 2700 DiagnoseIncompleteType(IDecl->getLocation(), T, 2701 diag::err_typecheck_decl_incomplete_type)) 2702 IDecl->setInvalidDecl(); 2703 } 2704 // File scope. C99 6.9.2p2: A declaration of an identifier for and 2705 // object that has file scope without an initializer, and without a 2706 // storage-class specifier or with the storage-class specifier "static", 2707 // constitutes a tentative definition. Note: A tentative definition with 2708 // external linkage is valid (C99 6.2.2p5). 2709 if (isTentativeDefinition(IDecl)) { 2710 if (T->isIncompleteArrayType()) { 2711 // C99 6.9.2 (p2, p5): Implicit initialization causes an incomplete 2712 // array to be completed. Don't issue a diagnostic. 2713 } else if (!IDecl->isInvalidDecl() && 2714 DiagnoseIncompleteType(IDecl->getLocation(), T, 2715 diag::err_typecheck_decl_incomplete_type)) 2716 // C99 6.9.2p3: If the declaration of an identifier for an object is 2717 // a tentative definition and has internal linkage (C99 6.2.2p3), the 2718 // declared type shall not be an incomplete type. 2719 IDecl->setInvalidDecl(); 2720 } 2721 if (IDecl->isFileVarDecl()) 2722 CheckForFileScopedRedefinitions(S, IDecl); 2723 } 2724 return NewGroup; 2725} 2726 2727/// ActOnParamDeclarator - Called from Parser::ParseFunctionDeclarator() 2728/// to introduce parameters into function prototype scope. 2729Sema::DeclTy * 2730Sema::ActOnParamDeclarator(Scope *S, Declarator &D) { 2731 const DeclSpec &DS = D.getDeclSpec(); 2732 2733 // Verify C99 6.7.5.3p2: The only SCS allowed is 'register'. 2734 VarDecl::StorageClass StorageClass = VarDecl::None; 2735 if (DS.getStorageClassSpec() == DeclSpec::SCS_register) { 2736 StorageClass = VarDecl::Register; 2737 } else if (DS.getStorageClassSpec() != DeclSpec::SCS_unspecified) { 2738 Diag(DS.getStorageClassSpecLoc(), 2739 diag::err_invalid_storage_class_in_func_decl); 2740 D.getMutableDeclSpec().ClearStorageClassSpecs(); 2741 } 2742 if (DS.isThreadSpecified()) { 2743 Diag(DS.getThreadSpecLoc(), 2744 diag::err_invalid_storage_class_in_func_decl); 2745 D.getMutableDeclSpec().ClearStorageClassSpecs(); 2746 } 2747 2748 // Check that there are no default arguments inside the type of this 2749 // parameter (C++ only). 2750 if (getLangOptions().CPlusPlus) 2751 CheckExtraCXXDefaultArguments(D); 2752 2753 // In this context, we *do not* check D.getInvalidType(). If the declarator 2754 // type was invalid, GetTypeForDeclarator() still returns a "valid" type, 2755 // though it will not reflect the user specified type. 2756 QualType parmDeclType = GetTypeForDeclarator(D, S); 2757 2758 assert(!parmDeclType.isNull() && "GetTypeForDeclarator() returned null type"); 2759 2760 // TODO: CHECK FOR CONFLICTS, multiple decls with same name in one scope. 2761 // Can this happen for params? We already checked that they don't conflict 2762 // among each other. Here they can only shadow globals, which is ok. 2763 IdentifierInfo *II = D.getIdentifier(); 2764 if (II) { 2765 if (NamedDecl *PrevDecl = LookupName(S, II, LookupOrdinaryName)) { 2766 if (PrevDecl->isTemplateParameter()) { 2767 // Maybe we will complain about the shadowed template parameter. 2768 DiagnoseTemplateParameterShadow(D.getIdentifierLoc(), PrevDecl); 2769 // Just pretend that we didn't see the previous declaration. 2770 PrevDecl = 0; 2771 } else if (S->isDeclScope(PrevDecl)) { 2772 Diag(D.getIdentifierLoc(), diag::err_param_redefinition) << II; 2773 2774 // Recover by removing the name 2775 II = 0; 2776 D.SetIdentifier(0, D.getIdentifierLoc()); 2777 } 2778 } 2779 } 2780 2781 // Perform the default function/array conversion (C99 6.7.5.3p[7,8]). 2782 // Doing the promotion here has a win and a loss. The win is the type for 2783 // both Decl's and DeclRefExpr's will match (a convenient invariant for the 2784 // code generator). The loss is the orginal type isn't preserved. For example: 2785 // 2786 // void func(int parmvardecl[5]) { // convert "int [5]" to "int *" 2787 // int blockvardecl[5]; 2788 // sizeof(parmvardecl); // size == 4 2789 // sizeof(blockvardecl); // size == 20 2790 // } 2791 // 2792 // For expressions, all implicit conversions are captured using the 2793 // ImplicitCastExpr AST node (we have no such mechanism for Decl's). 2794 // 2795 // FIXME: If a source translation tool needs to see the original type, then 2796 // we need to consider storing both types (in ParmVarDecl)... 2797 // 2798 if (parmDeclType->isArrayType()) { 2799 // int x[restrict 4] -> int *restrict 2800 parmDeclType = Context.getArrayDecayedType(parmDeclType); 2801 } else if (parmDeclType->isFunctionType()) 2802 parmDeclType = Context.getPointerType(parmDeclType); 2803 2804 ParmVarDecl *New = ParmVarDecl::Create(Context, CurContext, 2805 D.getIdentifierLoc(), II, 2806 parmDeclType, StorageClass, 2807 0); 2808 2809 if (D.getInvalidType()) 2810 New->setInvalidDecl(); 2811 2812 // Parameter declarators cannot be qualified (C++ [dcl.meaning]p1). 2813 if (D.getCXXScopeSpec().isSet()) { 2814 Diag(D.getIdentifierLoc(), diag::err_qualified_param_declarator) 2815 << D.getCXXScopeSpec().getRange(); 2816 New->setInvalidDecl(); 2817 } 2818 // Parameter declarators cannot be interface types. All ObjC objects are 2819 // passed by reference. 2820 if (parmDeclType->isObjCInterfaceType()) { 2821 Diag(D.getIdentifierLoc(), diag::err_object_cannot_be_by_value) 2822 << "passed"; 2823 New->setInvalidDecl(); 2824 } 2825 2826 // Add the parameter declaration into this scope. 2827 S->AddDecl(New); 2828 if (II) 2829 IdResolver.AddDecl(New); 2830 2831 ProcessDeclAttributes(New, D); 2832 return New; 2833 2834} 2835 2836void Sema::ActOnFinishKNRParamDeclarations(Scope *S, Declarator &D) { 2837 assert(D.getTypeObject(0).Kind == DeclaratorChunk::Function && 2838 "Not a function declarator!"); 2839 DeclaratorChunk::FunctionTypeInfo &FTI = D.getTypeObject(0).Fun; 2840 2841 // Verify 6.9.1p6: 'every identifier in the identifier list shall be declared' 2842 // for a K&R function. 2843 if (!FTI.hasPrototype) { 2844 for (unsigned i = 0, e = FTI.NumArgs; i != e; ++i) { 2845 if (FTI.ArgInfo[i].Param == 0) { 2846 Diag(FTI.ArgInfo[i].IdentLoc, diag::ext_param_not_declared) 2847 << FTI.ArgInfo[i].Ident; 2848 // Implicitly declare the argument as type 'int' for lack of a better 2849 // type. 2850 DeclSpec DS; 2851 const char* PrevSpec; // unused 2852 DS.SetTypeSpecType(DeclSpec::TST_int, FTI.ArgInfo[i].IdentLoc, 2853 PrevSpec); 2854 Declarator ParamD(DS, Declarator::KNRTypeListContext); 2855 ParamD.SetIdentifier(FTI.ArgInfo[i].Ident, FTI.ArgInfo[i].IdentLoc); 2856 FTI.ArgInfo[i].Param = ActOnParamDeclarator(S, ParamD); 2857 } 2858 } 2859 } 2860} 2861 2862Sema::DeclTy *Sema::ActOnStartOfFunctionDef(Scope *FnBodyScope, Declarator &D) { 2863 assert(getCurFunctionDecl() == 0 && "Function parsing confused"); 2864 assert(D.getTypeObject(0).Kind == DeclaratorChunk::Function && 2865 "Not a function declarator!"); 2866 DeclaratorChunk::FunctionTypeInfo &FTI = D.getTypeObject(0).Fun; 2867 2868 if (FTI.hasPrototype) { 2869 // FIXME: Diagnose arguments without names in C. 2870 } 2871 2872 Scope *ParentScope = FnBodyScope->getParent(); 2873 2874 return ActOnStartOfFunctionDef(FnBodyScope, 2875 ActOnDeclarator(ParentScope, D, 0, 2876 /*IsFunctionDefinition=*/true)); 2877} 2878 2879Sema::DeclTy *Sema::ActOnStartOfFunctionDef(Scope *FnBodyScope, DeclTy *D) { 2880 Decl *decl = static_cast<Decl*>(D); 2881 FunctionDecl *FD = cast<FunctionDecl>(decl); 2882 2883 // See if this is a redefinition. 2884 const FunctionDecl *Definition; 2885 if (FD->getBody(Definition)) { 2886 Diag(FD->getLocation(), diag::err_redefinition) << FD->getDeclName(); 2887 Diag(Definition->getLocation(), diag::note_previous_definition); 2888 } 2889 2890 // Builtin functions cannot be defined. 2891 if (unsigned BuiltinID = FD->getBuiltinID(Context)) { 2892 if (!Context.BuiltinInfo.isPredefinedLibFunction(BuiltinID)) { 2893 Diag(FD->getLocation(), diag::err_builtin_definition) << FD; 2894 FD->setInvalidDecl(); 2895 } 2896 } 2897 2898 PushDeclContext(FnBodyScope, FD); 2899 2900 // Check the validity of our function parameters 2901 CheckParmsForFunctionDef(FD); 2902 2903 // Introduce our parameters into the function scope 2904 for (unsigned p = 0, NumParams = FD->getNumParams(); p < NumParams; ++p) { 2905 ParmVarDecl *Param = FD->getParamDecl(p); 2906 Param->setOwningFunction(FD); 2907 2908 // If this has an identifier, add it to the scope stack. 2909 if (Param->getIdentifier()) 2910 PushOnScopeChains(Param, FnBodyScope); 2911 } 2912 2913 // Checking attributes of current function definition 2914 // dllimport attribute. 2915 if (FD->getAttr<DLLImportAttr>() && (!FD->getAttr<DLLExportAttr>())) { 2916 // dllimport attribute cannot be applied to definition. 2917 if (!(FD->getAttr<DLLImportAttr>())->isInherited()) { 2918 Diag(FD->getLocation(), 2919 diag::err_attribute_can_be_applied_only_to_symbol_declaration) 2920 << "dllimport"; 2921 FD->setInvalidDecl(); 2922 return FD; 2923 } else { 2924 // If a symbol previously declared dllimport is later defined, the 2925 // attribute is ignored in subsequent references, and a warning is 2926 // emitted. 2927 Diag(FD->getLocation(), 2928 diag::warn_redeclaration_without_attribute_prev_attribute_ignored) 2929 << FD->getNameAsCString() << "dllimport"; 2930 } 2931 } 2932 return FD; 2933} 2934 2935Sema::DeclTy *Sema::ActOnFinishFunctionBody(DeclTy *D, StmtArg BodyArg) { 2936 Decl *dcl = static_cast<Decl *>(D); 2937 Stmt *Body = static_cast<Stmt*>(BodyArg.release()); 2938 if (FunctionDecl *FD = dyn_cast_or_null<FunctionDecl>(dcl)) { 2939 FD->setBody(Body); 2940 assert(FD == getCurFunctionDecl() && "Function parsing confused"); 2941 } else if (ObjCMethodDecl *MD = dyn_cast_or_null<ObjCMethodDecl>(dcl)) { 2942 assert(MD == getCurMethodDecl() && "Method parsing confused"); 2943 MD->setBody((Stmt*)Body); 2944 } else { 2945 Body->Destroy(Context); 2946 return 0; 2947 } 2948 PopDeclContext(); 2949 // Verify and clean out per-function state. 2950 2951 // Check goto/label use. 2952 for (llvm::DenseMap<IdentifierInfo*, LabelStmt*>::iterator 2953 I = LabelMap.begin(), E = LabelMap.end(); I != E; ++I) { 2954 // Verify that we have no forward references left. If so, there was a goto 2955 // or address of a label taken, but no definition of it. Label fwd 2956 // definitions are indicated with a null substmt. 2957 if (I->second->getSubStmt() == 0) { 2958 LabelStmt *L = I->second; 2959 // Emit error. 2960 Diag(L->getIdentLoc(), diag::err_undeclared_label_use) << L->getName(); 2961 2962 // At this point, we have gotos that use the bogus label. Stitch it into 2963 // the function body so that they aren't leaked and that the AST is well 2964 // formed. 2965 if (Body) { 2966#if 0 2967 // FIXME: Why do this? Having a 'push_back' in CompoundStmt is ugly, 2968 // and the AST is malformed anyway. We should just blow away 'L'. 2969 L->setSubStmt(new (Context) NullStmt(L->getIdentLoc())); 2970 cast<CompoundStmt>(Body)->push_back(L); 2971#else 2972 L->Destroy(Context); 2973#endif 2974 } else { 2975 // The whole function wasn't parsed correctly, just delete this. 2976 L->Destroy(Context); 2977 } 2978 } 2979 } 2980 LabelMap.clear(); 2981 2982 return D; 2983} 2984 2985/// ImplicitlyDefineFunction - An undeclared identifier was used in a function 2986/// call, forming a call to an implicitly defined function (per C99 6.5.1p2). 2987NamedDecl *Sema::ImplicitlyDefineFunction(SourceLocation Loc, 2988 IdentifierInfo &II, Scope *S) { 2989 // Extension in C99. Legal in C90, but warn about it. 2990 if (getLangOptions().C99) 2991 Diag(Loc, diag::ext_implicit_function_decl) << &II; 2992 else 2993 Diag(Loc, diag::warn_implicit_function_decl) << &II; 2994 2995 // FIXME: handle stuff like: 2996 // void foo() { extern float X(); } 2997 // void bar() { X(); } <-- implicit decl for X in another scope. 2998 2999 // Set a Declarator for the implicit definition: int foo(); 3000 const char *Dummy; 3001 DeclSpec DS; 3002 bool Error = DS.SetTypeSpecType(DeclSpec::TST_int, Loc, Dummy); 3003 Error = Error; // Silence warning. 3004 assert(!Error && "Error setting up implicit decl!"); 3005 Declarator D(DS, Declarator::BlockContext); 3006 D.AddTypeInfo(DeclaratorChunk::getFunction(false, false, SourceLocation(), 3007 0, 0, 0, Loc, D), 3008 SourceLocation()); 3009 D.SetIdentifier(&II, Loc); 3010 3011 // Insert this function into translation-unit scope. 3012 3013 DeclContext *PrevDC = CurContext; 3014 CurContext = Context.getTranslationUnitDecl(); 3015 3016 FunctionDecl *FD = 3017 dyn_cast<FunctionDecl>(static_cast<Decl*>(ActOnDeclarator(TUScope, D, 0))); 3018 FD->setImplicit(); 3019 3020 CurContext = PrevDC; 3021 3022 AddKnownFunctionAttributes(FD); 3023 3024 return FD; 3025} 3026 3027/// \brief Adds any function attributes that we know a priori based on 3028/// the declaration of this function. 3029/// 3030/// These attributes can apply both to implicitly-declared builtins 3031/// (like __builtin___printf_chk) or to library-declared functions 3032/// like NSLog or printf. 3033void Sema::AddKnownFunctionAttributes(FunctionDecl *FD) { 3034 if (FD->isInvalidDecl()) 3035 return; 3036 3037 // If this is a built-in function, map its builtin attributes to 3038 // actual attributes. 3039 if (unsigned BuiltinID = FD->getBuiltinID(Context)) { 3040 // Handle printf-formatting attributes. 3041 unsigned FormatIdx; 3042 bool HasVAListArg; 3043 if (Context.BuiltinInfo.isPrintfLike(BuiltinID, FormatIdx, HasVAListArg)) { 3044 if (!FD->getAttr<FormatAttr>()) 3045 FD->addAttr(new FormatAttr("printf", FormatIdx + 1, FormatIdx + 2)); 3046 } 3047 3048 // Mark const if we don't care about errno and that is the only 3049 // thing preventing the function from being const. This allows 3050 // IRgen to use LLVM intrinsics for such functions. 3051 if (!getLangOptions().MathErrno && 3052 Context.BuiltinInfo.isConstWithoutErrno(BuiltinID)) { 3053 if (!FD->getAttr<ConstAttr>()) 3054 FD->addAttr(new ConstAttr()); 3055 } 3056 } 3057 3058 IdentifierInfo *Name = FD->getIdentifier(); 3059 if (!Name) 3060 return; 3061 if ((!getLangOptions().CPlusPlus && 3062 FD->getDeclContext()->isTranslationUnit()) || 3063 (isa<LinkageSpecDecl>(FD->getDeclContext()) && 3064 cast<LinkageSpecDecl>(FD->getDeclContext())->getLanguage() == 3065 LinkageSpecDecl::lang_c)) { 3066 // Okay: this could be a libc/libm/Objective-C function we know 3067 // about. 3068 } else 3069 return; 3070 3071 unsigned KnownID; 3072 for (KnownID = 0; KnownID != id_num_known_functions; ++KnownID) 3073 if (KnownFunctionIDs[KnownID] == Name) 3074 break; 3075 3076 switch (KnownID) { 3077 case id_NSLog: 3078 case id_NSLogv: 3079 if (const FormatAttr *Format = FD->getAttr<FormatAttr>()) { 3080 // FIXME: We known better than our headers. 3081 const_cast<FormatAttr *>(Format)->setType("printf"); 3082 } else 3083 FD->addAttr(new FormatAttr("printf", 1, 2)); 3084 break; 3085 3086 case id_asprintf: 3087 case id_vasprintf: 3088 if (!FD->getAttr<FormatAttr>()) 3089 FD->addAttr(new FormatAttr("printf", 2, 3)); 3090 break; 3091 3092 default: 3093 // Unknown function or known function without any attributes to 3094 // add. Do nothing. 3095 break; 3096 } 3097} 3098 3099TypedefDecl *Sema::ParseTypedefDecl(Scope *S, Declarator &D, QualType T, 3100 Decl *LastDeclarator) { 3101 assert(D.getIdentifier() && "Wrong callback for declspec without declarator"); 3102 assert(!T.isNull() && "GetTypeForDeclarator() returned null type"); 3103 3104 // Scope manipulation handled by caller. 3105 TypedefDecl *NewTD = TypedefDecl::Create(Context, CurContext, 3106 D.getIdentifierLoc(), 3107 D.getIdentifier(), 3108 T); 3109 NewTD->setNextDeclarator(LastDeclarator); 3110 if (D.getInvalidType()) 3111 NewTD->setInvalidDecl(); 3112 return NewTD; 3113} 3114 3115/// ActOnTag - This is invoked when we see 'struct foo' or 'struct {'. In the 3116/// former case, Name will be non-null. In the later case, Name will be null. 3117/// TagSpec indicates what kind of tag this is. TK indicates whether this is a 3118/// reference/declaration/definition of a tag. 3119Sema::DeclTy *Sema::ActOnTag(Scope *S, unsigned TagSpec, TagKind TK, 3120 SourceLocation KWLoc, const CXXScopeSpec &SS, 3121 IdentifierInfo *Name, SourceLocation NameLoc, 3122 AttributeList *Attr) { 3123 // If this is not a definition, it must have a name. 3124 assert((Name != 0 || TK == TK_Definition) && 3125 "Nameless record must be a definition!"); 3126 3127 TagDecl::TagKind Kind; 3128 switch (TagSpec) { 3129 default: assert(0 && "Unknown tag type!"); 3130 case DeclSpec::TST_struct: Kind = TagDecl::TK_struct; break; 3131 case DeclSpec::TST_union: Kind = TagDecl::TK_union; break; 3132 case DeclSpec::TST_class: Kind = TagDecl::TK_class; break; 3133 case DeclSpec::TST_enum: Kind = TagDecl::TK_enum; break; 3134 } 3135 3136 DeclContext *SearchDC = CurContext; 3137 DeclContext *DC = CurContext; 3138 NamedDecl *PrevDecl = 0; 3139 3140 bool Invalid = false; 3141 3142 if (Name && SS.isNotEmpty()) { 3143 // We have a nested-name tag ('struct foo::bar'). 3144 3145 // Check for invalid 'foo::'. 3146 if (SS.isInvalid()) { 3147 Name = 0; 3148 goto CreateNewDecl; 3149 } 3150 3151 DC = static_cast<DeclContext*>(SS.getScopeRep()); 3152 SearchDC = DC; 3153 // Look-up name inside 'foo::'. 3154 PrevDecl = dyn_cast_or_null<TagDecl>( 3155 LookupQualifiedName(DC, Name, LookupTagName, true).getAsDecl()); 3156 3157 // A tag 'foo::bar' must already exist. 3158 if (PrevDecl == 0) { 3159 Diag(NameLoc, diag::err_not_tag_in_scope) << Name << SS.getRange(); 3160 Name = 0; 3161 goto CreateNewDecl; 3162 } 3163 } else if (Name) { 3164 // If this is a named struct, check to see if there was a previous forward 3165 // declaration or definition. 3166 // FIXME: We're looking into outer scopes here, even when we 3167 // shouldn't be. Doing so can result in ambiguities that we 3168 // shouldn't be diagnosing. 3169 LookupResult R = LookupName(S, Name, LookupTagName, 3170 /*RedeclarationOnly=*/(TK != TK_Reference)); 3171 if (R.isAmbiguous()) { 3172 DiagnoseAmbiguousLookup(R, Name, NameLoc); 3173 // FIXME: This is not best way to recover from case like: 3174 // 3175 // struct S s; 3176 // 3177 // causes needless err_ovl_no_viable_function_in_init latter. 3178 Name = 0; 3179 PrevDecl = 0; 3180 Invalid = true; 3181 } 3182 else 3183 PrevDecl = R; 3184 3185 if (!getLangOptions().CPlusPlus && TK != TK_Reference) { 3186 // FIXME: This makes sure that we ignore the contexts associated 3187 // with C structs, unions, and enums when looking for a matching 3188 // tag declaration or definition. See the similar lookup tweak 3189 // in Sema::LookupName; is there a better way to deal with this? 3190 while (isa<RecordDecl>(SearchDC) || isa<EnumDecl>(SearchDC)) 3191 SearchDC = SearchDC->getParent(); 3192 } 3193 } 3194 3195 if (PrevDecl && PrevDecl->isTemplateParameter()) { 3196 // Maybe we will complain about the shadowed template parameter. 3197 DiagnoseTemplateParameterShadow(NameLoc, PrevDecl); 3198 // Just pretend that we didn't see the previous declaration. 3199 PrevDecl = 0; 3200 } 3201 3202 if (PrevDecl) { 3203 // Check whether the previous declaration is usable. 3204 (void)DiagnoseUseOfDecl(PrevDecl, NameLoc); 3205 3206 if (TagDecl *PrevTagDecl = dyn_cast<TagDecl>(PrevDecl)) { 3207 // If this is a use of a previous tag, or if the tag is already declared 3208 // in the same scope (so that the definition/declaration completes or 3209 // rementions the tag), reuse the decl. 3210 if (TK == TK_Reference || isDeclInScope(PrevDecl, SearchDC, S)) { 3211 // Make sure that this wasn't declared as an enum and now used as a 3212 // struct or something similar. 3213 if (PrevTagDecl->getTagKind() != Kind) { 3214 Diag(KWLoc, diag::err_use_with_wrong_tag) << Name; 3215 Diag(PrevDecl->getLocation(), diag::note_previous_use); 3216 // Recover by making this an anonymous redefinition. 3217 Name = 0; 3218 PrevDecl = 0; 3219 Invalid = true; 3220 } else { 3221 // If this is a use, just return the declaration we found. 3222 3223 // FIXME: In the future, return a variant or some other clue 3224 // for the consumer of this Decl to know it doesn't own it. 3225 // For our current ASTs this shouldn't be a problem, but will 3226 // need to be changed with DeclGroups. 3227 if (TK == TK_Reference) 3228 return PrevDecl; 3229 3230 // Diagnose attempts to redefine a tag. 3231 if (TK == TK_Definition) { 3232 if (TagDecl *Def = PrevTagDecl->getDefinition(Context)) { 3233 Diag(NameLoc, diag::err_redefinition) << Name; 3234 Diag(Def->getLocation(), diag::note_previous_definition); 3235 // If this is a redefinition, recover by making this 3236 // struct be anonymous, which will make any later 3237 // references get the previous definition. 3238 Name = 0; 3239 PrevDecl = 0; 3240 Invalid = true; 3241 } else { 3242 // If the type is currently being defined, complain 3243 // about a nested redefinition. 3244 TagType *Tag = cast<TagType>(Context.getTagDeclType(PrevTagDecl)); 3245 if (Tag->isBeingDefined()) { 3246 Diag(NameLoc, diag::err_nested_redefinition) << Name; 3247 Diag(PrevTagDecl->getLocation(), 3248 diag::note_previous_definition); 3249 Name = 0; 3250 PrevDecl = 0; 3251 Invalid = true; 3252 } 3253 } 3254 3255 // Okay, this is definition of a previously declared or referenced 3256 // tag PrevDecl. We're going to create a new Decl for it. 3257 } 3258 } 3259 // If we get here we have (another) forward declaration or we 3260 // have a definition. Just create a new decl. 3261 } else { 3262 // If we get here, this is a definition of a new tag type in a nested 3263 // scope, e.g. "struct foo; void bar() { struct foo; }", just create a 3264 // new decl/type. We set PrevDecl to NULL so that the entities 3265 // have distinct types. 3266 PrevDecl = 0; 3267 } 3268 // If we get here, we're going to create a new Decl. If PrevDecl 3269 // is non-NULL, it's a definition of the tag declared by 3270 // PrevDecl. If it's NULL, we have a new definition. 3271 } else { 3272 // PrevDecl is a namespace, template, or anything else 3273 // that lives in the IDNS_Tag identifier namespace. 3274 if (isDeclInScope(PrevDecl, SearchDC, S)) { 3275 // The tag name clashes with a namespace name, issue an error and 3276 // recover by making this tag be anonymous. 3277 Diag(NameLoc, diag::err_redefinition_different_kind) << Name; 3278 Diag(PrevDecl->getLocation(), diag::note_previous_definition); 3279 Name = 0; 3280 PrevDecl = 0; 3281 Invalid = true; 3282 } else { 3283 // The existing declaration isn't relevant to us; we're in a 3284 // new scope, so clear out the previous declaration. 3285 PrevDecl = 0; 3286 } 3287 } 3288 } else if (TK == TK_Reference && SS.isEmpty() && Name && 3289 (Kind != TagDecl::TK_enum)) { 3290 // C++ [basic.scope.pdecl]p5: 3291 // -- for an elaborated-type-specifier of the form 3292 // 3293 // class-key identifier 3294 // 3295 // if the elaborated-type-specifier is used in the 3296 // decl-specifier-seq or parameter-declaration-clause of a 3297 // function defined in namespace scope, the identifier is 3298 // declared as a class-name in the namespace that contains 3299 // the declaration; otherwise, except as a friend 3300 // declaration, the identifier is declared in the smallest 3301 // non-class, non-function-prototype scope that contains the 3302 // declaration. 3303 // 3304 // C99 6.7.2.3p8 has a similar (but not identical!) provision for 3305 // C structs and unions. 3306 3307 // Find the context where we'll be declaring the tag. 3308 // FIXME: We would like to maintain the current DeclContext as the 3309 // lexical context, 3310 while (SearchDC->isRecord()) 3311 SearchDC = SearchDC->getParent(); 3312 3313 // Find the scope where we'll be declaring the tag. 3314 while (S->isClassScope() || 3315 (getLangOptions().CPlusPlus && S->isFunctionPrototypeScope()) || 3316 ((S->getFlags() & Scope::DeclScope) == 0) || 3317 (S->getEntity() && 3318 ((DeclContext *)S->getEntity())->isTransparentContext())) 3319 S = S->getParent(); 3320 } 3321 3322CreateNewDecl: 3323 3324 // If there is an identifier, use the location of the identifier as the 3325 // location of the decl, otherwise use the location of the struct/union 3326 // keyword. 3327 SourceLocation Loc = NameLoc.isValid() ? NameLoc : KWLoc; 3328 3329 // Otherwise, create a new declaration. If there is a previous 3330 // declaration of the same entity, the two will be linked via 3331 // PrevDecl. 3332 TagDecl *New; 3333 3334 if (Kind == TagDecl::TK_enum) { 3335 // FIXME: Tag decls should be chained to any simultaneous vardecls, e.g.: 3336 // enum X { A, B, C } D; D should chain to X. 3337 New = EnumDecl::Create(Context, SearchDC, Loc, Name, 3338 cast_or_null<EnumDecl>(PrevDecl)); 3339 // If this is an undefined enum, warn. 3340 if (TK != TK_Definition) Diag(Loc, diag::ext_forward_ref_enum); 3341 } else { 3342 // struct/union/class 3343 3344 // FIXME: Tag decls should be chained to any simultaneous vardecls, e.g.: 3345 // struct X { int A; } D; D should chain to X. 3346 if (getLangOptions().CPlusPlus) 3347 // FIXME: Look for a way to use RecordDecl for simple structs. 3348 New = CXXRecordDecl::Create(Context, Kind, SearchDC, Loc, Name, 3349 cast_or_null<CXXRecordDecl>(PrevDecl)); 3350 else 3351 New = RecordDecl::Create(Context, Kind, SearchDC, Loc, Name, 3352 cast_or_null<RecordDecl>(PrevDecl)); 3353 } 3354 3355 if (Kind != TagDecl::TK_enum) { 3356 // Handle #pragma pack: if the #pragma pack stack has non-default 3357 // alignment, make up a packed attribute for this decl. These 3358 // attributes are checked when the ASTContext lays out the 3359 // structure. 3360 // 3361 // It is important for implementing the correct semantics that this 3362 // happen here (in act on tag decl). The #pragma pack stack is 3363 // maintained as a result of parser callbacks which can occur at 3364 // many points during the parsing of a struct declaration (because 3365 // the #pragma tokens are effectively skipped over during the 3366 // parsing of the struct). 3367 if (unsigned Alignment = getPragmaPackAlignment()) 3368 New->addAttr(new PackedAttr(Alignment * 8)); 3369 } 3370 3371 if (getLangOptions().CPlusPlus && SS.isEmpty() && Name && !Invalid) { 3372 // C++ [dcl.typedef]p3: 3373 // [...] Similarly, in a given scope, a class or enumeration 3374 // shall not be declared with the same name as a typedef-name 3375 // that is declared in that scope and refers to a type other 3376 // than the class or enumeration itself. 3377 LookupResult Lookup = LookupName(S, Name, LookupOrdinaryName, true); 3378 TypedefDecl *PrevTypedef = 0; 3379 if (Lookup.getKind() == LookupResult::Found) 3380 PrevTypedef = dyn_cast<TypedefDecl>(Lookup.getAsDecl()); 3381 3382 if (PrevTypedef && isDeclInScope(PrevTypedef, SearchDC, S) && 3383 Context.getCanonicalType(Context.getTypeDeclType(PrevTypedef)) != 3384 Context.getCanonicalType(Context.getTypeDeclType(New))) { 3385 Diag(Loc, diag::err_tag_definition_of_typedef) 3386 << Context.getTypeDeclType(New) 3387 << PrevTypedef->getUnderlyingType(); 3388 Diag(PrevTypedef->getLocation(), diag::note_previous_definition); 3389 Invalid = true; 3390 } 3391 } 3392 3393 if (Invalid) 3394 New->setInvalidDecl(); 3395 3396 if (Attr) 3397 ProcessDeclAttributeList(New, Attr); 3398 3399 // If we're declaring or defining a tag in function prototype scope 3400 // in C, note that this type can only be used within the function. 3401 if (Name && S->isFunctionPrototypeScope() && !getLangOptions().CPlusPlus) 3402 Diag(Loc, diag::warn_decl_in_param_list) << Context.getTagDeclType(New); 3403 3404 // Set the lexical context. If the tag has a C++ scope specifier, the 3405 // lexical context will be different from the semantic context. 3406 New->setLexicalDeclContext(CurContext); 3407 3408 if (TK == TK_Definition) 3409 New->startDefinition(); 3410 3411 // If this has an identifier, add it to the scope stack. 3412 if (Name) { 3413 S = getNonFieldDeclScope(S); 3414 PushOnScopeChains(New, S); 3415 } else { 3416 CurContext->addDecl(New); 3417 } 3418 3419 return New; 3420} 3421 3422void Sema::ActOnTagStartDefinition(Scope *S, DeclTy *TagD) { 3423 AdjustDeclIfTemplate(TagD); 3424 TagDecl *Tag = cast<TagDecl>((Decl *)TagD); 3425 3426 // Enter the tag context. 3427 PushDeclContext(S, Tag); 3428 3429 if (CXXRecordDecl *Record = dyn_cast<CXXRecordDecl>(Tag)) { 3430 FieldCollector->StartClass(); 3431 3432 if (Record->getIdentifier()) { 3433 // C++ [class]p2: 3434 // [...] The class-name is also inserted into the scope of the 3435 // class itself; this is known as the injected-class-name. For 3436 // purposes of access checking, the injected-class-name is treated 3437 // as if it were a public member name. 3438 RecordDecl *InjectedClassName 3439 = CXXRecordDecl::Create(Context, Record->getTagKind(), 3440 CurContext, Record->getLocation(), 3441 Record->getIdentifier(), Record); 3442 InjectedClassName->setImplicit(); 3443 PushOnScopeChains(InjectedClassName, S); 3444 } 3445 } 3446} 3447 3448void Sema::ActOnTagFinishDefinition(Scope *S, DeclTy *TagD) { 3449 AdjustDeclIfTemplate(TagD); 3450 TagDecl *Tag = cast<TagDecl>((Decl *)TagD); 3451 3452 if (isa<CXXRecordDecl>(Tag)) 3453 FieldCollector->FinishClass(); 3454 3455 // Exit this scope of this tag's definition. 3456 PopDeclContext(); 3457 3458 // Notify the consumer that we've defined a tag. 3459 Consumer.HandleTagDeclDefinition(Tag); 3460} 3461 3462bool Sema::VerifyBitField(SourceLocation FieldLoc, IdentifierInfo *FieldName, 3463 QualType FieldTy, const Expr *BitWidth) { 3464 // FIXME: 6.7.2.1p4 - verify the field type. 3465 3466 llvm::APSInt Value; 3467 if (VerifyIntegerConstantExpression(BitWidth, &Value)) 3468 return true; 3469 3470 // Zero-width bitfield is ok for anonymous field. 3471 if (Value == 0 && FieldName) 3472 return Diag(FieldLoc, diag::err_bitfield_has_zero_width) << FieldName; 3473 3474 if (Value.isNegative()) 3475 return Diag(FieldLoc, diag::err_bitfield_has_negative_width) << FieldName; 3476 3477 uint64_t TypeSize = Context.getTypeSize(FieldTy); 3478 // FIXME: We won't need the 0 size once we check that the field type is valid. 3479 if (TypeSize && Value.getZExtValue() > TypeSize) 3480 return Diag(FieldLoc, diag::err_bitfield_width_exceeds_type_size) 3481 << FieldName << (unsigned)TypeSize; 3482 3483 return false; 3484} 3485 3486/// ActOnField - Each field of a struct/union/class is passed into this in order 3487/// to create a FieldDecl object for it. 3488Sema::DeclTy *Sema::ActOnField(Scope *S, DeclTy *TagD, 3489 SourceLocation DeclStart, 3490 Declarator &D, ExprTy *BitfieldWidth) { 3491 IdentifierInfo *II = D.getIdentifier(); 3492 Expr *BitWidth = (Expr*)BitfieldWidth; 3493 SourceLocation Loc = DeclStart; 3494 RecordDecl *Record = (RecordDecl *)TagD; 3495 if (II) Loc = D.getIdentifierLoc(); 3496 3497 // FIXME: Unnamed fields can be handled in various different ways, for 3498 // example, unnamed unions inject all members into the struct namespace! 3499 3500 QualType T = GetTypeForDeclarator(D, S); 3501 assert(!T.isNull() && "GetTypeForDeclarator() returned null type"); 3502 bool InvalidDecl = false; 3503 3504 // C99 6.7.2.1p8: A member of a structure or union may have any type other 3505 // than a variably modified type. 3506 if (T->isVariablyModifiedType()) { 3507 bool SizeIsNegative; 3508 QualType FixedTy = TryToFixInvalidVariablyModifiedType(T, Context, 3509 SizeIsNegative); 3510 if (!FixedTy.isNull()) { 3511 Diag(Loc, diag::warn_illegal_constant_array_size); 3512 T = FixedTy; 3513 } else { 3514 if (SizeIsNegative) 3515 Diag(Loc, diag::err_typecheck_negative_array_size); 3516 else 3517 Diag(Loc, diag::err_typecheck_field_variable_size); 3518 T = Context.IntTy; 3519 InvalidDecl = true; 3520 } 3521 } 3522 3523 if (BitWidth) { 3524 if (VerifyBitField(Loc, II, T, BitWidth)) 3525 InvalidDecl = true; 3526 } else { 3527 // Not a bitfield. 3528 3529 // validate II. 3530 3531 } 3532 3533 FieldDecl *NewFD = FieldDecl::Create(Context, Record, 3534 Loc, II, T, BitWidth, 3535 D.getDeclSpec().getStorageClassSpec() == 3536 DeclSpec::SCS_mutable); 3537 3538 if (II) { 3539 NamedDecl *PrevDecl = LookupName(S, II, LookupMemberName, true); 3540 if (PrevDecl && isDeclInScope(PrevDecl, CurContext, S) 3541 && !isa<TagDecl>(PrevDecl)) { 3542 Diag(Loc, diag::err_duplicate_member) << II; 3543 Diag(PrevDecl->getLocation(), diag::note_previous_declaration); 3544 NewFD->setInvalidDecl(); 3545 Record->setInvalidDecl(); 3546 } 3547 } 3548 3549 if (getLangOptions().CPlusPlus) { 3550 CheckExtraCXXDefaultArguments(D); 3551 if (!T->isPODType()) 3552 cast<CXXRecordDecl>(Record)->setPOD(false); 3553 } 3554 3555 ProcessDeclAttributes(NewFD, D); 3556 if (T.isObjCGCWeak()) 3557 Diag(Loc, diag::warn_attribute_weak_on_field); 3558 3559 if (D.getInvalidType() || InvalidDecl) 3560 NewFD->setInvalidDecl(); 3561 3562 if (II) { 3563 PushOnScopeChains(NewFD, S); 3564 } else 3565 Record->addDecl(NewFD); 3566 3567 return NewFD; 3568} 3569 3570/// TranslateIvarVisibility - Translate visibility from a token ID to an 3571/// AST enum value. 3572static ObjCIvarDecl::AccessControl 3573TranslateIvarVisibility(tok::ObjCKeywordKind ivarVisibility) { 3574 switch (ivarVisibility) { 3575 default: assert(0 && "Unknown visitibility kind"); 3576 case tok::objc_private: return ObjCIvarDecl::Private; 3577 case tok::objc_public: return ObjCIvarDecl::Public; 3578 case tok::objc_protected: return ObjCIvarDecl::Protected; 3579 case tok::objc_package: return ObjCIvarDecl::Package; 3580 } 3581} 3582 3583/// ActOnIvar - Each ivar field of an objective-c class is passed into this 3584/// in order to create an IvarDecl object for it. 3585Sema::DeclTy *Sema::ActOnIvar(Scope *S, 3586 SourceLocation DeclStart, 3587 Declarator &D, ExprTy *BitfieldWidth, 3588 tok::ObjCKeywordKind Visibility) { 3589 3590 IdentifierInfo *II = D.getIdentifier(); 3591 Expr *BitWidth = (Expr*)BitfieldWidth; 3592 SourceLocation Loc = DeclStart; 3593 if (II) Loc = D.getIdentifierLoc(); 3594 3595 // FIXME: Unnamed fields can be handled in various different ways, for 3596 // example, unnamed unions inject all members into the struct namespace! 3597 3598 QualType T = GetTypeForDeclarator(D, S); 3599 assert(!T.isNull() && "GetTypeForDeclarator() returned null type"); 3600 bool InvalidDecl = false; 3601 3602 if (BitWidth) { 3603 // 6.7.2.1p3, 6.7.2.1p4 3604 if (VerifyBitField(Loc, II, T, BitWidth)) 3605 InvalidDecl = true; 3606 } else { 3607 // Not a bitfield. 3608 3609 // validate II. 3610 3611 } 3612 3613 // C99 6.7.2.1p8: A member of a structure or union may have any type other 3614 // than a variably modified type. 3615 if (T->isVariablyModifiedType()) { 3616 Diag(Loc, diag::err_typecheck_ivar_variable_size); 3617 InvalidDecl = true; 3618 } 3619 3620 // Get the visibility (access control) for this ivar. 3621 ObjCIvarDecl::AccessControl ac = 3622 Visibility != tok::objc_not_keyword ? TranslateIvarVisibility(Visibility) 3623 : ObjCIvarDecl::None; 3624 3625 // Construct the decl. 3626 ObjCIvarDecl *NewID = ObjCIvarDecl::Create(Context, CurContext, Loc, II, T,ac, 3627 (Expr *)BitfieldWidth); 3628 3629 if (II) { 3630 NamedDecl *PrevDecl = LookupName(S, II, LookupMemberName, true); 3631 if (PrevDecl && isDeclInScope(PrevDecl, CurContext, S) 3632 && !isa<TagDecl>(PrevDecl)) { 3633 Diag(Loc, diag::err_duplicate_member) << II; 3634 Diag(PrevDecl->getLocation(), diag::note_previous_declaration); 3635 NewID->setInvalidDecl(); 3636 } 3637 } 3638 3639 // Process attributes attached to the ivar. 3640 ProcessDeclAttributes(NewID, D); 3641 3642 if (D.getInvalidType() || InvalidDecl) 3643 NewID->setInvalidDecl(); 3644 3645 if (II) { 3646 // FIXME: When interfaces are DeclContexts, we'll need to add 3647 // these to the interface. 3648 S->AddDecl(NewID); 3649 IdResolver.AddDecl(NewID); 3650 } 3651 3652 return NewID; 3653} 3654 3655void Sema::ActOnFields(Scope* S, 3656 SourceLocation RecLoc, DeclTy *RecDecl, 3657 DeclTy **Fields, unsigned NumFields, 3658 SourceLocation LBrac, SourceLocation RBrac, 3659 AttributeList *Attr) { 3660 Decl *EnclosingDecl = static_cast<Decl*>(RecDecl); 3661 assert(EnclosingDecl && "missing record or interface decl"); 3662 RecordDecl *Record = dyn_cast<RecordDecl>(EnclosingDecl); 3663 3664 // Verify that all the fields are okay. 3665 unsigned NumNamedMembers = 0; 3666 llvm::SmallVector<FieldDecl*, 32> RecFields; 3667 3668 for (unsigned i = 0; i != NumFields; ++i) { 3669 FieldDecl *FD = cast_or_null<FieldDecl>(static_cast<Decl*>(Fields[i])); 3670 assert(FD && "missing field decl"); 3671 3672 // Get the type for the field. 3673 Type *FDTy = FD->getType().getTypePtr(); 3674 3675 if (!FD->isAnonymousStructOrUnion()) { 3676 // Remember all fields written by the user. 3677 RecFields.push_back(FD); 3678 } 3679 3680 // C99 6.7.2.1p2 - A field may not be a function type. 3681 if (FDTy->isFunctionType()) { 3682 Diag(FD->getLocation(), diag::err_field_declared_as_function) 3683 << FD->getDeclName(); 3684 FD->setInvalidDecl(); 3685 EnclosingDecl->setInvalidDecl(); 3686 continue; 3687 } 3688 // C99 6.7.2.1p2 - A field may not be an incomplete type except... 3689 if (FDTy->isIncompleteType()) { 3690 if (!Record) { // Incomplete ivar type is always an error. 3691 DiagnoseIncompleteType(FD->getLocation(), FD->getType(), 3692 diag::err_field_incomplete); 3693 FD->setInvalidDecl(); 3694 EnclosingDecl->setInvalidDecl(); 3695 continue; 3696 } 3697 if (i != NumFields-1 || // ... that the last member ... 3698 !Record->isStruct() || // ... of a structure ... 3699 !FDTy->isArrayType()) { //... may have incomplete array type. 3700 DiagnoseIncompleteType(FD->getLocation(), FD->getType(), 3701 diag::err_field_incomplete); 3702 FD->setInvalidDecl(); 3703 EnclosingDecl->setInvalidDecl(); 3704 continue; 3705 } 3706 if (NumNamedMembers < 1) { //... must have more than named member ... 3707 Diag(FD->getLocation(), diag::err_flexible_array_empty_struct) 3708 << FD->getDeclName(); 3709 FD->setInvalidDecl(); 3710 EnclosingDecl->setInvalidDecl(); 3711 continue; 3712 } 3713 // Okay, we have a legal flexible array member at the end of the struct. 3714 if (Record) 3715 Record->setHasFlexibleArrayMember(true); 3716 } 3717 /// C99 6.7.2.1p2 - a struct ending in a flexible array member cannot be the 3718 /// field of another structure or the element of an array. 3719 if (const RecordType *FDTTy = FDTy->getAsRecordType()) { 3720 if (FDTTy->getDecl()->hasFlexibleArrayMember()) { 3721 // If this is a member of a union, then entire union becomes "flexible". 3722 if (Record && Record->isUnion()) { 3723 Record->setHasFlexibleArrayMember(true); 3724 } else { 3725 // If this is a struct/class and this is not the last element, reject 3726 // it. Note that GCC supports variable sized arrays in the middle of 3727 // structures. 3728 if (i != NumFields-1) { 3729 Diag(FD->getLocation(), diag::err_variable_sized_type_in_struct) 3730 << FD->getDeclName(); 3731 FD->setInvalidDecl(); 3732 EnclosingDecl->setInvalidDecl(); 3733 continue; 3734 } 3735 // We support flexible arrays at the end of structs in other structs 3736 // as an extension. 3737 Diag(FD->getLocation(), diag::ext_flexible_array_in_struct) 3738 << FD->getDeclName(); 3739 if (Record) 3740 Record->setHasFlexibleArrayMember(true); 3741 } 3742 } 3743 } 3744 /// A field cannot be an Objective-c object 3745 if (FDTy->isObjCInterfaceType()) { 3746 Diag(FD->getLocation(), diag::err_statically_allocated_object); 3747 FD->setInvalidDecl(); 3748 EnclosingDecl->setInvalidDecl(); 3749 continue; 3750 } 3751 // Keep track of the number of named members. 3752 if (FD->getIdentifier()) 3753 ++NumNamedMembers; 3754 } 3755 3756 // Okay, we successfully defined 'Record'. 3757 if (Record) { 3758 Record->completeDefinition(Context); 3759 } else { 3760 ObjCIvarDecl **ClsFields = reinterpret_cast<ObjCIvarDecl**>(&RecFields[0]); 3761 if (ObjCInterfaceDecl *ID = dyn_cast<ObjCInterfaceDecl>(EnclosingDecl)) { 3762 ID->setIVarList(ClsFields, RecFields.size(), Context); 3763 ID->setLocEnd(RBrac); 3764 3765 // Must enforce the rule that ivars in the base classes may not be 3766 // duplicates. 3767 if (ID->getSuperClass()) { 3768 for (ObjCInterfaceDecl::ivar_iterator IVI = ID->ivar_begin(), 3769 IVE = ID->ivar_end(); IVI != IVE; ++IVI) { 3770 ObjCIvarDecl* Ivar = (*IVI); 3771 IdentifierInfo *II = Ivar->getIdentifier(); 3772 ObjCIvarDecl* prevIvar = ID->getSuperClass()->lookupInstanceVariable(II); 3773 if (prevIvar) { 3774 Diag(Ivar->getLocation(), diag::err_duplicate_member) << II; 3775 Diag(prevIvar->getLocation(), diag::note_previous_declaration); 3776 } 3777 } 3778 } 3779 } 3780 else if (ObjCImplementationDecl *IMPDecl = 3781 dyn_cast<ObjCImplementationDecl>(EnclosingDecl)) { 3782 assert(IMPDecl && "ActOnFields - missing ObjCImplementationDecl"); 3783 IMPDecl->setIVarList(ClsFields, RecFields.size(), Context); 3784 CheckImplementationIvars(IMPDecl, ClsFields, RecFields.size(), RBrac); 3785 } 3786 } 3787 3788 if (Attr) 3789 ProcessDeclAttributeList(Record, Attr); 3790} 3791 3792Sema::DeclTy *Sema::ActOnEnumConstant(Scope *S, DeclTy *theEnumDecl, 3793 DeclTy *lastEnumConst, 3794 SourceLocation IdLoc, IdentifierInfo *Id, 3795 SourceLocation EqualLoc, ExprTy *val) { 3796 EnumDecl *TheEnumDecl = cast<EnumDecl>(static_cast<Decl*>(theEnumDecl)); 3797 EnumConstantDecl *LastEnumConst = 3798 cast_or_null<EnumConstantDecl>(static_cast<Decl*>(lastEnumConst)); 3799 Expr *Val = static_cast<Expr*>(val); 3800 3801 // The scope passed in may not be a decl scope. Zip up the scope tree until 3802 // we find one that is. 3803 S = getNonFieldDeclScope(S); 3804 3805 // Verify that there isn't already something declared with this name in this 3806 // scope. 3807 NamedDecl *PrevDecl = LookupName(S, Id, LookupOrdinaryName); 3808 if (PrevDecl && PrevDecl->isTemplateParameter()) { 3809 // Maybe we will complain about the shadowed template parameter. 3810 DiagnoseTemplateParameterShadow(IdLoc, PrevDecl); 3811 // Just pretend that we didn't see the previous declaration. 3812 PrevDecl = 0; 3813 } 3814 3815 if (PrevDecl) { 3816 // When in C++, we may get a TagDecl with the same name; in this case the 3817 // enum constant will 'hide' the tag. 3818 assert((getLangOptions().CPlusPlus || !isa<TagDecl>(PrevDecl)) && 3819 "Received TagDecl when not in C++!"); 3820 if (!isa<TagDecl>(PrevDecl) && isDeclInScope(PrevDecl, CurContext, S)) { 3821 if (isa<EnumConstantDecl>(PrevDecl)) 3822 Diag(IdLoc, diag::err_redefinition_of_enumerator) << Id; 3823 else 3824 Diag(IdLoc, diag::err_redefinition) << Id; 3825 Diag(PrevDecl->getLocation(), diag::note_previous_definition); 3826 Val->Destroy(Context); 3827 return 0; 3828 } 3829 } 3830 3831 llvm::APSInt EnumVal(32); 3832 QualType EltTy; 3833 if (Val) { 3834 // Make sure to promote the operand type to int. 3835 UsualUnaryConversions(Val); 3836 3837 // C99 6.7.2.2p2: Make sure we have an integer constant expression. 3838 SourceLocation ExpLoc; 3839 if (VerifyIntegerConstantExpression(Val, &EnumVal)) { 3840 Val->Destroy(Context); 3841 Val = 0; // Just forget about it. 3842 } else { 3843 EltTy = Val->getType(); 3844 } 3845 } 3846 3847 if (!Val) { 3848 if (LastEnumConst) { 3849 // Assign the last value + 1. 3850 EnumVal = LastEnumConst->getInitVal(); 3851 ++EnumVal; 3852 3853 // Check for overflow on increment. 3854 if (EnumVal < LastEnumConst->getInitVal()) 3855 Diag(IdLoc, diag::warn_enum_value_overflow); 3856 3857 EltTy = LastEnumConst->getType(); 3858 } else { 3859 // First value, set to zero. 3860 EltTy = Context.IntTy; 3861 EnumVal.zextOrTrunc(static_cast<uint32_t>(Context.getTypeSize(EltTy))); 3862 } 3863 } 3864 3865 EnumConstantDecl *New = 3866 EnumConstantDecl::Create(Context, TheEnumDecl, IdLoc, Id, EltTy, 3867 Val, EnumVal); 3868 3869 // Register this decl in the current scope stack. 3870 PushOnScopeChains(New, S); 3871 3872 return New; 3873} 3874 3875// FIXME: For consistency with ActOnFields(), we should have the parser 3876// pass in the source location for the left/right braces. 3877void Sema::ActOnEnumBody(SourceLocation EnumLoc, DeclTy *EnumDeclX, 3878 DeclTy **Elements, unsigned NumElements) { 3879 EnumDecl *Enum = cast<EnumDecl>(static_cast<Decl*>(EnumDeclX)); 3880 QualType EnumType = Context.getTypeDeclType(Enum); 3881 3882 // TODO: If the result value doesn't fit in an int, it must be a long or long 3883 // long value. ISO C does not support this, but GCC does as an extension, 3884 // emit a warning. 3885 unsigned IntWidth = Context.Target.getIntWidth(); 3886 3887 // Verify that all the values are okay, compute the size of the values, and 3888 // reverse the list. 3889 unsigned NumNegativeBits = 0; 3890 unsigned NumPositiveBits = 0; 3891 3892 // Keep track of whether all elements have type int. 3893 bool AllElementsInt = true; 3894 3895 for (unsigned i = 0; i != NumElements; ++i) { 3896 EnumConstantDecl *ECD = 3897 cast_or_null<EnumConstantDecl>(static_cast<Decl*>(Elements[i])); 3898 if (!ECD) continue; // Already issued a diagnostic. 3899 3900 // If the enum value doesn't fit in an int, emit an extension warning. 3901 const llvm::APSInt &InitVal = ECD->getInitVal(); 3902 assert(InitVal.getBitWidth() >= IntWidth && 3903 "Should have promoted value to int"); 3904 if (InitVal.getBitWidth() > IntWidth) { 3905 llvm::APSInt V(InitVal); 3906 V.trunc(IntWidth); 3907 V.extend(InitVal.getBitWidth()); 3908 if (V != InitVal) 3909 Diag(ECD->getLocation(), diag::ext_enum_value_not_int) 3910 << InitVal.toString(10); 3911 } 3912 3913 // Keep track of the size of positive and negative values. 3914 if (InitVal.isUnsigned() || InitVal.isNonNegative()) 3915 NumPositiveBits = std::max(NumPositiveBits, 3916 (unsigned)InitVal.getActiveBits()); 3917 else 3918 NumNegativeBits = std::max(NumNegativeBits, 3919 (unsigned)InitVal.getMinSignedBits()); 3920 3921 // Keep track of whether every enum element has type int (very commmon). 3922 if (AllElementsInt) 3923 AllElementsInt = ECD->getType() == Context.IntTy; 3924 } 3925 3926 // Figure out the type that should be used for this enum. 3927 // FIXME: Support attribute(packed) on enums and -fshort-enums. 3928 QualType BestType; 3929 unsigned BestWidth; 3930 3931 if (NumNegativeBits) { 3932 // If there is a negative value, figure out the smallest integer type (of 3933 // int/long/longlong) that fits. 3934 if (NumNegativeBits <= IntWidth && NumPositiveBits < IntWidth) { 3935 BestType = Context.IntTy; 3936 BestWidth = IntWidth; 3937 } else { 3938 BestWidth = Context.Target.getLongWidth(); 3939 3940 if (NumNegativeBits <= BestWidth && NumPositiveBits < BestWidth) 3941 BestType = Context.LongTy; 3942 else { 3943 BestWidth = Context.Target.getLongLongWidth(); 3944 3945 if (NumNegativeBits > BestWidth || NumPositiveBits >= BestWidth) 3946 Diag(Enum->getLocation(), diag::warn_enum_too_large); 3947 BestType = Context.LongLongTy; 3948 } 3949 } 3950 } else { 3951 // If there is no negative value, figure out which of uint, ulong, ulonglong 3952 // fits. 3953 if (NumPositiveBits <= IntWidth) { 3954 BestType = Context.UnsignedIntTy; 3955 BestWidth = IntWidth; 3956 } else if (NumPositiveBits <= 3957 (BestWidth = Context.Target.getLongWidth())) { 3958 BestType = Context.UnsignedLongTy; 3959 } else { 3960 BestWidth = Context.Target.getLongLongWidth(); 3961 assert(NumPositiveBits <= BestWidth && 3962 "How could an initializer get larger than ULL?"); 3963 BestType = Context.UnsignedLongLongTy; 3964 } 3965 } 3966 3967 // Loop over all of the enumerator constants, changing their types to match 3968 // the type of the enum if needed. 3969 for (unsigned i = 0; i != NumElements; ++i) { 3970 EnumConstantDecl *ECD = 3971 cast_or_null<EnumConstantDecl>(static_cast<Decl*>(Elements[i])); 3972 if (!ECD) continue; // Already issued a diagnostic. 3973 3974 // Standard C says the enumerators have int type, but we allow, as an 3975 // extension, the enumerators to be larger than int size. If each 3976 // enumerator value fits in an int, type it as an int, otherwise type it the 3977 // same as the enumerator decl itself. This means that in "enum { X = 1U }" 3978 // that X has type 'int', not 'unsigned'. 3979 if (ECD->getType() == Context.IntTy) { 3980 // Make sure the init value is signed. 3981 llvm::APSInt IV = ECD->getInitVal(); 3982 IV.setIsSigned(true); 3983 ECD->setInitVal(IV); 3984 3985 if (getLangOptions().CPlusPlus) 3986 // C++ [dcl.enum]p4: Following the closing brace of an 3987 // enum-specifier, each enumerator has the type of its 3988 // enumeration. 3989 ECD->setType(EnumType); 3990 continue; // Already int type. 3991 } 3992 3993 // Determine whether the value fits into an int. 3994 llvm::APSInt InitVal = ECD->getInitVal(); 3995 bool FitsInInt; 3996 if (InitVal.isUnsigned() || !InitVal.isNegative()) 3997 FitsInInt = InitVal.getActiveBits() < IntWidth; 3998 else 3999 FitsInInt = InitVal.getMinSignedBits() <= IntWidth; 4000 4001 // If it fits into an integer type, force it. Otherwise force it to match 4002 // the enum decl type. 4003 QualType NewTy; 4004 unsigned NewWidth; 4005 bool NewSign; 4006 if (FitsInInt) { 4007 NewTy = Context.IntTy; 4008 NewWidth = IntWidth; 4009 NewSign = true; 4010 } else if (ECD->getType() == BestType) { 4011 // Already the right type! 4012 if (getLangOptions().CPlusPlus) 4013 // C++ [dcl.enum]p4: Following the closing brace of an 4014 // enum-specifier, each enumerator has the type of its 4015 // enumeration. 4016 ECD->setType(EnumType); 4017 continue; 4018 } else { 4019 NewTy = BestType; 4020 NewWidth = BestWidth; 4021 NewSign = BestType->isSignedIntegerType(); 4022 } 4023 4024 // Adjust the APSInt value. 4025 InitVal.extOrTrunc(NewWidth); 4026 InitVal.setIsSigned(NewSign); 4027 ECD->setInitVal(InitVal); 4028 4029 // Adjust the Expr initializer and type. 4030 if (ECD->getInitExpr()) 4031 ECD->setInitExpr(new (Context) ImplicitCastExpr(NewTy, ECD->getInitExpr(), 4032 /*isLvalue=*/false)); 4033 if (getLangOptions().CPlusPlus) 4034 // C++ [dcl.enum]p4: Following the closing brace of an 4035 // enum-specifier, each enumerator has the type of its 4036 // enumeration. 4037 ECD->setType(EnumType); 4038 else 4039 ECD->setType(NewTy); 4040 } 4041 4042 Enum->completeDefinition(Context, BestType); 4043} 4044 4045Sema::DeclTy *Sema::ActOnFileScopeAsmDecl(SourceLocation Loc, 4046 ExprArg expr) { 4047 StringLiteral *AsmString = cast<StringLiteral>((Expr*)expr.release()); 4048 4049 return FileScopeAsmDecl::Create(Context, CurContext, Loc, AsmString); 4050} 4051 4052