SemaDecl.cpp revision afcc7b425bcdc8ef8092f5f510486d2f246c2d86
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 // If this typename is deprecated, emit a warning. 68 DiagnoseUseOfDeprecatedDecl(IIDecl, NameLoc); 69 70 return Context.getTypeDeclType(TD).getAsOpaquePtr(); 71 } 72 73 if (ObjCInterfaceDecl *IDecl = dyn_cast<ObjCInterfaceDecl>(IIDecl)) { 74 // If this typename is deprecated, emit a warning. 75 DiagnoseUseOfDeprecatedDecl(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 return MergeCXXFunctionDecl(New, Old); 595 } 596 597 // Fall through for conflicting redeclarations and redefinitions. 598 } 599 600 // C: Function types need to be compatible, not identical. This handles 601 // duplicate function decls like "void f(int); void f(enum X);" properly. 602 if (!getLangOptions().CPlusPlus && 603 Context.typesAreCompatible(OldQType, NewQType)) { 604 const FunctionType *NewFuncType = NewQType->getAsFunctionType(); 605 const FunctionTypeProto *OldProto = 0; 606 if (isa<FunctionTypeNoProto>(NewFuncType) && 607 (OldProto = OldQType->getAsFunctionTypeProto())) { 608 // The old declaration provided a function prototype, but the 609 // new declaration does not. Merge in the prototype. 610 llvm::SmallVector<QualType, 16> ParamTypes(OldProto->arg_type_begin(), 611 OldProto->arg_type_end()); 612 NewQType = Context.getFunctionType(NewFuncType->getResultType(), 613 &ParamTypes[0], ParamTypes.size(), 614 OldProto->isVariadic(), 615 OldProto->getTypeQuals()); 616 New->setType(NewQType); 617 New->setInheritedPrototype(); 618 619 // Synthesize a parameter for each argument type. 620 llvm::SmallVector<ParmVarDecl*, 16> Params; 621 for (FunctionTypeProto::arg_type_iterator 622 ParamType = OldProto->arg_type_begin(), 623 ParamEnd = OldProto->arg_type_end(); 624 ParamType != ParamEnd; ++ParamType) { 625 ParmVarDecl *Param = ParmVarDecl::Create(Context, New, 626 SourceLocation(), 0, 627 *ParamType, VarDecl::None, 628 0); 629 Param->setImplicit(); 630 Params.push_back(Param); 631 } 632 633 New->setParams(Context, &Params[0], Params.size()); 634 635 } 636 637 MergeAttributes(New, Old); 638 639 return false; 640 } 641 642 // A function that has already been declared has been redeclared or defined 643 // with a different type- show appropriate diagnostic 644 if (unsigned BuiltinID = Old->getBuiltinID(Context)) { 645 // The user has declared a builtin function with an incompatible 646 // signature. 647 if (Context.BuiltinInfo.isPredefinedLibFunction(BuiltinID)) { 648 // The function the user is redeclaring is a library-defined 649 // function like 'malloc' or 'printf'. Warn about the 650 // redeclaration, then ignore it. 651 Diag(New->getLocation(), diag::warn_redecl_library_builtin) << New; 652 Diag(Old->getLocation(), diag::note_previous_builtin_declaration) 653 << Old << Old->getType(); 654 return false; 655 } 656 657 PrevDiag = diag::note_previous_builtin_declaration; 658 } 659 660 Diag(New->getLocation(), diag::err_conflicting_types) << New->getDeclName(); 661 Diag(Old->getLocation(), PrevDiag) << Old << Old->getType(); 662 return true; 663} 664 665/// Predicate for C "tentative" external object definitions (C99 6.9.2). 666static bool isTentativeDefinition(VarDecl *VD) { 667 if (VD->isFileVarDecl()) 668 return (!VD->getInit() && 669 (VD->getStorageClass() == VarDecl::None || 670 VD->getStorageClass() == VarDecl::Static)); 671 return false; 672} 673 674/// CheckForFileScopedRedefinitions - Make sure we forgo redefinition errors 675/// when dealing with C "tentative" external object definitions (C99 6.9.2). 676void Sema::CheckForFileScopedRedefinitions(Scope *S, VarDecl *VD) { 677 bool VDIsTentative = isTentativeDefinition(VD); 678 bool VDIsIncompleteArray = VD->getType()->isIncompleteArrayType(); 679 680 // FIXME: I don't think this will actually see all of the 681 // redefinitions. Can't we check this property on-the-fly? 682 for (IdentifierResolver::iterator I = IdResolver.begin(VD->getIdentifier()), 683 E = IdResolver.end(); 684 I != E; ++I) { 685 if (*I != VD && isDeclInScope(*I, VD->getDeclContext(), S)) { 686 VarDecl *OldDecl = dyn_cast<VarDecl>(*I); 687 688 // Handle the following case: 689 // int a[10]; 690 // int a[]; - the code below makes sure we set the correct type. 691 // int a[11]; - this is an error, size isn't 10. 692 if (OldDecl && VDIsTentative && VDIsIncompleteArray && 693 OldDecl->getType()->isConstantArrayType()) 694 VD->setType(OldDecl->getType()); 695 696 // Check for "tentative" definitions. We can't accomplish this in 697 // MergeVarDecl since the initializer hasn't been attached. 698 if (!OldDecl || isTentativeDefinition(OldDecl) || VDIsTentative) 699 continue; 700 701 // Handle __private_extern__ just like extern. 702 if (OldDecl->getStorageClass() != VarDecl::Extern && 703 OldDecl->getStorageClass() != VarDecl::PrivateExtern && 704 VD->getStorageClass() != VarDecl::Extern && 705 VD->getStorageClass() != VarDecl::PrivateExtern) { 706 Diag(VD->getLocation(), diag::err_redefinition) << VD->getDeclName(); 707 Diag(OldDecl->getLocation(), diag::note_previous_definition); 708 // One redefinition error is enough. 709 break; 710 } 711 } 712 } 713} 714 715/// MergeVarDecl - We just parsed a variable 'New' which has the same name 716/// and scope as a previous declaration 'Old'. Figure out how to resolve this 717/// situation, merging decls or emitting diagnostics as appropriate. 718/// 719/// Tentative definition rules (C99 6.9.2p2) are checked by 720/// FinalizeDeclaratorGroup. Unfortunately, we can't analyze tentative 721/// definitions here, since the initializer hasn't been attached. 722/// 723bool Sema::MergeVarDecl(VarDecl *New, Decl *OldD) { 724 // Verify the old decl was also a variable. 725 VarDecl *Old = dyn_cast<VarDecl>(OldD); 726 if (!Old) { 727 Diag(New->getLocation(), diag::err_redefinition_different_kind) 728 << New->getDeclName(); 729 Diag(OldD->getLocation(), diag::note_previous_definition); 730 return true; 731 } 732 733 MergeAttributes(New, Old); 734 735 // Merge the types 736 QualType MergedT = Context.mergeTypes(New->getType(), Old->getType()); 737 if (MergedT.isNull()) { 738 Diag(New->getLocation(), diag::err_redefinition_different_type) 739 << New->getDeclName(); 740 Diag(Old->getLocation(), diag::note_previous_definition); 741 return true; 742 } 743 New->setType(MergedT); 744 // C99 6.2.2p4: Check if we have a static decl followed by a non-static. 745 if (New->getStorageClass() == VarDecl::Static && 746 (Old->getStorageClass() == VarDecl::None || 747 Old->getStorageClass() == VarDecl::Extern)) { 748 Diag(New->getLocation(), diag::err_static_non_static) << New->getDeclName(); 749 Diag(Old->getLocation(), diag::note_previous_definition); 750 return true; 751 } 752 // C99 6.2.2p4: Check if we have a non-static decl followed by a static. 753 if (New->getStorageClass() != VarDecl::Static && 754 Old->getStorageClass() == VarDecl::Static) { 755 Diag(New->getLocation(), diag::err_non_static_static) << New->getDeclName(); 756 Diag(Old->getLocation(), diag::note_previous_definition); 757 return true; 758 } 759 // Variables with external linkage are analyzed in FinalizeDeclaratorGroup. 760 if (New->getStorageClass() != VarDecl::Extern && !New->isFileVarDecl()) { 761 Diag(New->getLocation(), diag::err_redefinition) << New->getDeclName(); 762 Diag(Old->getLocation(), diag::note_previous_definition); 763 return true; 764 } 765 return false; 766} 767 768/// CheckParmsForFunctionDef - Check that the parameters of the given 769/// function are appropriate for the definition of a function. This 770/// takes care of any checks that cannot be performed on the 771/// declaration itself, e.g., that the types of each of the function 772/// parameters are complete. 773bool Sema::CheckParmsForFunctionDef(FunctionDecl *FD) { 774 bool HasInvalidParm = false; 775 for (unsigned p = 0, NumParams = FD->getNumParams(); p < NumParams; ++p) { 776 ParmVarDecl *Param = FD->getParamDecl(p); 777 778 // C99 6.7.5.3p4: the parameters in a parameter type list in a 779 // function declarator that is part of a function definition of 780 // that function shall not have incomplete type. 781 if (!Param->isInvalidDecl() && 782 DiagnoseIncompleteType(Param->getLocation(), Param->getType(), 783 diag::err_typecheck_decl_incomplete_type)) { 784 Param->setInvalidDecl(); 785 HasInvalidParm = true; 786 } 787 788 // C99 6.9.1p5: If the declarator includes a parameter type list, the 789 // declaration of each parameter shall include an identifier. 790 if (Param->getIdentifier() == 0 && 791 !Param->isImplicit() && 792 !getLangOptions().CPlusPlus) 793 Diag(Param->getLocation(), diag::err_parameter_name_omitted); 794 } 795 796 return HasInvalidParm; 797} 798 799/// ParsedFreeStandingDeclSpec - This method is invoked when a declspec with 800/// no declarator (e.g. "struct foo;") is parsed. 801Sema::DeclTy *Sema::ParsedFreeStandingDeclSpec(Scope *S, DeclSpec &DS) { 802 TagDecl *Tag = 0; 803 if (DS.getTypeSpecType() == DeclSpec::TST_class || 804 DS.getTypeSpecType() == DeclSpec::TST_struct || 805 DS.getTypeSpecType() == DeclSpec::TST_union || 806 DS.getTypeSpecType() == DeclSpec::TST_enum) 807 Tag = dyn_cast<TagDecl>(static_cast<Decl *>(DS.getTypeRep())); 808 809 if (RecordDecl *Record = dyn_cast_or_null<RecordDecl>(Tag)) { 810 if (!Record->getDeclName() && Record->isDefinition() && 811 DS.getStorageClassSpec() != DeclSpec::SCS_typedef) 812 return BuildAnonymousStructOrUnion(S, DS, Record); 813 814 // Microsoft allows unnamed struct/union fields. Don't complain 815 // about them. 816 // FIXME: Should we support Microsoft's extensions in this area? 817 if (Record->getDeclName() && getLangOptions().Microsoft) 818 return Tag; 819 } 820 821 if (!DS.isMissingDeclaratorOk() && 822 DS.getTypeSpecType() != DeclSpec::TST_error) { 823 // Warn about typedefs of enums without names, since this is an 824 // extension in both Microsoft an GNU. 825 if (DS.getStorageClassSpec() == DeclSpec::SCS_typedef && 826 Tag && isa<EnumDecl>(Tag)) { 827 Diag(DS.getSourceRange().getBegin(), diag::ext_typedef_without_a_name) 828 << DS.getSourceRange(); 829 return Tag; 830 } 831 832 Diag(DS.getSourceRange().getBegin(), diag::err_no_declarators) 833 << DS.getSourceRange(); 834 return 0; 835 } 836 837 return Tag; 838} 839 840/// InjectAnonymousStructOrUnionMembers - Inject the members of the 841/// anonymous struct or union AnonRecord into the owning context Owner 842/// and scope S. This routine will be invoked just after we realize 843/// that an unnamed union or struct is actually an anonymous union or 844/// struct, e.g., 845/// 846/// @code 847/// union { 848/// int i; 849/// float f; 850/// }; // InjectAnonymousStructOrUnionMembers called here to inject i and 851/// // f into the surrounding scope.x 852/// @endcode 853/// 854/// This routine is recursive, injecting the names of nested anonymous 855/// structs/unions into the owning context and scope as well. 856bool Sema::InjectAnonymousStructOrUnionMembers(Scope *S, DeclContext *Owner, 857 RecordDecl *AnonRecord) { 858 bool Invalid = false; 859 for (RecordDecl::field_iterator F = AnonRecord->field_begin(), 860 FEnd = AnonRecord->field_end(); 861 F != FEnd; ++F) { 862 if ((*F)->getDeclName()) { 863 NamedDecl *PrevDecl = LookupQualifiedName(Owner, (*F)->getDeclName(), 864 LookupOrdinaryName, true); 865 if (PrevDecl && !isa<TagDecl>(PrevDecl)) { 866 // C++ [class.union]p2: 867 // The names of the members of an anonymous union shall be 868 // distinct from the names of any other entity in the 869 // scope in which the anonymous union is declared. 870 unsigned diagKind 871 = AnonRecord->isUnion()? diag::err_anonymous_union_member_redecl 872 : diag::err_anonymous_struct_member_redecl; 873 Diag((*F)->getLocation(), diagKind) 874 << (*F)->getDeclName(); 875 Diag(PrevDecl->getLocation(), diag::note_previous_declaration); 876 Invalid = true; 877 } else { 878 // C++ [class.union]p2: 879 // For the purpose of name lookup, after the anonymous union 880 // definition, the members of the anonymous union are 881 // considered to have been defined in the scope in which the 882 // anonymous union is declared. 883 Owner->makeDeclVisibleInContext(*F); 884 S->AddDecl(*F); 885 IdResolver.AddDecl(*F); 886 } 887 } else if (const RecordType *InnerRecordType 888 = (*F)->getType()->getAsRecordType()) { 889 RecordDecl *InnerRecord = InnerRecordType->getDecl(); 890 if (InnerRecord->isAnonymousStructOrUnion()) 891 Invalid = Invalid || 892 InjectAnonymousStructOrUnionMembers(S, Owner, InnerRecord); 893 } 894 } 895 896 return Invalid; 897} 898 899/// ActOnAnonymousStructOrUnion - Handle the declaration of an 900/// anonymous structure or union. Anonymous unions are a C++ feature 901/// (C++ [class.union]) and a GNU C extension; anonymous structures 902/// are a GNU C and GNU C++ extension. 903Sema::DeclTy *Sema::BuildAnonymousStructOrUnion(Scope *S, DeclSpec &DS, 904 RecordDecl *Record) { 905 DeclContext *Owner = Record->getDeclContext(); 906 907 // Diagnose whether this anonymous struct/union is an extension. 908 if (Record->isUnion() && !getLangOptions().CPlusPlus) 909 Diag(Record->getLocation(), diag::ext_anonymous_union); 910 else if (!Record->isUnion()) 911 Diag(Record->getLocation(), diag::ext_anonymous_struct); 912 913 // C and C++ require different kinds of checks for anonymous 914 // structs/unions. 915 bool Invalid = false; 916 if (getLangOptions().CPlusPlus) { 917 const char* PrevSpec = 0; 918 // C++ [class.union]p3: 919 // Anonymous unions declared in a named namespace or in the 920 // global namespace shall be declared static. 921 if (DS.getStorageClassSpec() != DeclSpec::SCS_static && 922 (isa<TranslationUnitDecl>(Owner) || 923 (isa<NamespaceDecl>(Owner) && 924 cast<NamespaceDecl>(Owner)->getDeclName()))) { 925 Diag(Record->getLocation(), diag::err_anonymous_union_not_static); 926 Invalid = true; 927 928 // Recover by adding 'static'. 929 DS.SetStorageClassSpec(DeclSpec::SCS_static, SourceLocation(), PrevSpec); 930 } 931 // C++ [class.union]p3: 932 // A storage class is not allowed in a declaration of an 933 // anonymous union in a class scope. 934 else if (DS.getStorageClassSpec() != DeclSpec::SCS_unspecified && 935 isa<RecordDecl>(Owner)) { 936 Diag(DS.getStorageClassSpecLoc(), 937 diag::err_anonymous_union_with_storage_spec); 938 Invalid = true; 939 940 // Recover by removing the storage specifier. 941 DS.SetStorageClassSpec(DeclSpec::SCS_unspecified, SourceLocation(), 942 PrevSpec); 943 } 944 945 // C++ [class.union]p2: 946 // The member-specification of an anonymous union shall only 947 // define non-static data members. [Note: nested types and 948 // functions cannot be declared within an anonymous union. ] 949 for (DeclContext::decl_iterator Mem = Record->decls_begin(), 950 MemEnd = Record->decls_end(); 951 Mem != MemEnd; ++Mem) { 952 if (FieldDecl *FD = dyn_cast<FieldDecl>(*Mem)) { 953 // C++ [class.union]p3: 954 // An anonymous union shall not have private or protected 955 // members (clause 11). 956 if (FD->getAccess() == AS_protected || FD->getAccess() == AS_private) { 957 Diag(FD->getLocation(), diag::err_anonymous_record_nonpublic_member) 958 << (int)Record->isUnion() << (int)(FD->getAccess() == AS_protected); 959 Invalid = true; 960 } 961 } else if ((*Mem)->isImplicit()) { 962 // Any implicit members are fine. 963 } else if (isa<TagDecl>(*Mem) && (*Mem)->getDeclContext() != Record) { 964 // This is a type that showed up in an 965 // elaborated-type-specifier inside the anonymous struct or 966 // union, but which actually declares a type outside of the 967 // anonymous struct or union. It's okay. 968 } else if (RecordDecl *MemRecord = dyn_cast<RecordDecl>(*Mem)) { 969 if (!MemRecord->isAnonymousStructOrUnion() && 970 MemRecord->getDeclName()) { 971 // This is a nested type declaration. 972 Diag(MemRecord->getLocation(), diag::err_anonymous_record_with_type) 973 << (int)Record->isUnion(); 974 Invalid = true; 975 } 976 } else { 977 // We have something that isn't a non-static data 978 // member. Complain about it. 979 unsigned DK = diag::err_anonymous_record_bad_member; 980 if (isa<TypeDecl>(*Mem)) 981 DK = diag::err_anonymous_record_with_type; 982 else if (isa<FunctionDecl>(*Mem)) 983 DK = diag::err_anonymous_record_with_function; 984 else if (isa<VarDecl>(*Mem)) 985 DK = diag::err_anonymous_record_with_static; 986 Diag((*Mem)->getLocation(), DK) 987 << (int)Record->isUnion(); 988 Invalid = true; 989 } 990 } 991 } else { 992 // FIXME: Check GNU C semantics 993 if (Record->isUnion() && !Owner->isRecord()) { 994 Diag(Record->getLocation(), diag::err_anonymous_union_not_member) 995 << (int)getLangOptions().CPlusPlus; 996 Invalid = true; 997 } 998 } 999 1000 if (!Record->isUnion() && !Owner->isRecord()) { 1001 Diag(Record->getLocation(), diag::err_anonymous_struct_not_member) 1002 << (int)getLangOptions().CPlusPlus; 1003 Invalid = true; 1004 } 1005 1006 // Create a declaration for this anonymous struct/union. 1007 NamedDecl *Anon = 0; 1008 if (RecordDecl *OwningClass = dyn_cast<RecordDecl>(Owner)) { 1009 Anon = FieldDecl::Create(Context, OwningClass, Record->getLocation(), 1010 /*IdentifierInfo=*/0, 1011 Context.getTypeDeclType(Record), 1012 /*BitWidth=*/0, /*Mutable=*/false); 1013 Anon->setAccess(AS_public); 1014 if (getLangOptions().CPlusPlus) 1015 FieldCollector->Add(cast<FieldDecl>(Anon)); 1016 } else { 1017 VarDecl::StorageClass SC; 1018 switch (DS.getStorageClassSpec()) { 1019 default: assert(0 && "Unknown storage class!"); 1020 case DeclSpec::SCS_unspecified: SC = VarDecl::None; break; 1021 case DeclSpec::SCS_extern: SC = VarDecl::Extern; break; 1022 case DeclSpec::SCS_static: SC = VarDecl::Static; break; 1023 case DeclSpec::SCS_auto: SC = VarDecl::Auto; break; 1024 case DeclSpec::SCS_register: SC = VarDecl::Register; break; 1025 case DeclSpec::SCS_private_extern: SC = VarDecl::PrivateExtern; break; 1026 case DeclSpec::SCS_mutable: 1027 // mutable can only appear on non-static class members, so it's always 1028 // an error here 1029 Diag(Record->getLocation(), diag::err_mutable_nonmember); 1030 Invalid = true; 1031 SC = VarDecl::None; 1032 break; 1033 } 1034 1035 Anon = VarDecl::Create(Context, Owner, Record->getLocation(), 1036 /*IdentifierInfo=*/0, 1037 Context.getTypeDeclType(Record), 1038 SC, DS.getSourceRange().getBegin()); 1039 } 1040 Anon->setImplicit(); 1041 1042 // Add the anonymous struct/union object to the current 1043 // context. We'll be referencing this object when we refer to one of 1044 // its members. 1045 Owner->addDecl(Anon); 1046 1047 // Inject the members of the anonymous struct/union into the owning 1048 // context and into the identifier resolver chain for name lookup 1049 // purposes. 1050 if (InjectAnonymousStructOrUnionMembers(S, Owner, Record)) 1051 Invalid = true; 1052 1053 // Mark this as an anonymous struct/union type. Note that we do not 1054 // do this until after we have already checked and injected the 1055 // members of this anonymous struct/union type, because otherwise 1056 // the members could be injected twice: once by DeclContext when it 1057 // builds its lookup table, and once by 1058 // InjectAnonymousStructOrUnionMembers. 1059 Record->setAnonymousStructOrUnion(true); 1060 1061 if (Invalid) 1062 Anon->setInvalidDecl(); 1063 1064 return Anon; 1065} 1066 1067bool Sema::CheckSingleInitializer(Expr *&Init, QualType DeclType, 1068 bool DirectInit) { 1069 // Get the type before calling CheckSingleAssignmentConstraints(), since 1070 // it can promote the expression. 1071 QualType InitType = Init->getType(); 1072 1073 if (getLangOptions().CPlusPlus) { 1074 // FIXME: I dislike this error message. A lot. 1075 if (PerformImplicitConversion(Init, DeclType, "initializing", DirectInit)) 1076 return Diag(Init->getSourceRange().getBegin(), 1077 diag::err_typecheck_convert_incompatible) 1078 << DeclType << Init->getType() << "initializing" 1079 << Init->getSourceRange(); 1080 1081 return false; 1082 } 1083 1084 AssignConvertType ConvTy = CheckSingleAssignmentConstraints(DeclType, Init); 1085 return DiagnoseAssignmentResult(ConvTy, Init->getLocStart(), DeclType, 1086 InitType, Init, "initializing"); 1087} 1088 1089bool Sema::CheckStringLiteralInit(StringLiteral *strLiteral, QualType &DeclT) { 1090 const ArrayType *AT = Context.getAsArrayType(DeclT); 1091 1092 if (const IncompleteArrayType *IAT = dyn_cast<IncompleteArrayType>(AT)) { 1093 // C99 6.7.8p14. We have an array of character type with unknown size 1094 // being initialized to a string literal. 1095 llvm::APSInt ConstVal(32); 1096 ConstVal = strLiteral->getByteLength() + 1; 1097 // Return a new array type (C99 6.7.8p22). 1098 DeclT = Context.getConstantArrayType(IAT->getElementType(), ConstVal, 1099 ArrayType::Normal, 0); 1100 } else { 1101 const ConstantArrayType *CAT = cast<ConstantArrayType>(AT); 1102 // C99 6.7.8p14. We have an array of character type with known size. 1103 // FIXME: Avoid truncation for 64-bit length strings. 1104 if (strLiteral->getByteLength() > (unsigned)CAT->getSize().getZExtValue()) 1105 Diag(strLiteral->getSourceRange().getBegin(), 1106 diag::warn_initializer_string_for_char_array_too_long) 1107 << strLiteral->getSourceRange(); 1108 } 1109 // Set type from "char *" to "constant array of char". 1110 strLiteral->setType(DeclT); 1111 // For now, we always return false (meaning success). 1112 return false; 1113} 1114 1115StringLiteral *Sema::IsStringLiteralInit(Expr *Init, QualType DeclType) { 1116 const ArrayType *AT = Context.getAsArrayType(DeclType); 1117 if (AT && AT->getElementType()->isCharType()) { 1118 return dyn_cast<StringLiteral>(Init->IgnoreParens()); 1119 } 1120 return 0; 1121} 1122 1123bool Sema::CheckInitializerTypes(Expr *&Init, QualType &DeclType, 1124 SourceLocation InitLoc, 1125 DeclarationName InitEntity, 1126 bool DirectInit) { 1127 if (DeclType->isDependentType() || Init->isTypeDependent()) 1128 return false; 1129 1130 // C++ [dcl.init.ref]p1: 1131 // A variable declared to be a T&, that is "reference to type T" 1132 // (8.3.2), shall be initialized by an object, or function, of 1133 // type T or by an object that can be converted into a T. 1134 if (DeclType->isReferenceType()) 1135 return CheckReferenceInit(Init, DeclType, 0, false, DirectInit); 1136 1137 // C99 6.7.8p3: The type of the entity to be initialized shall be an array 1138 // of unknown size ("[]") or an object type that is not a variable array type. 1139 if (const VariableArrayType *VAT = Context.getAsVariableArrayType(DeclType)) 1140 return Diag(InitLoc, diag::err_variable_object_no_init) 1141 << VAT->getSizeExpr()->getSourceRange(); 1142 1143 InitListExpr *InitList = dyn_cast<InitListExpr>(Init); 1144 if (!InitList) { 1145 // FIXME: Handle wide strings 1146 if (StringLiteral *strLiteral = IsStringLiteralInit(Init, DeclType)) 1147 return CheckStringLiteralInit(strLiteral, DeclType); 1148 1149 // C++ [dcl.init]p14: 1150 // -- If the destination type is a (possibly cv-qualified) class 1151 // type: 1152 if (getLangOptions().CPlusPlus && DeclType->isRecordType()) { 1153 QualType DeclTypeC = Context.getCanonicalType(DeclType); 1154 QualType InitTypeC = Context.getCanonicalType(Init->getType()); 1155 1156 // -- If the initialization is direct-initialization, or if it is 1157 // copy-initialization where the cv-unqualified version of the 1158 // source type is the same class as, or a derived class of, the 1159 // class of the destination, constructors are considered. 1160 if ((DeclTypeC.getUnqualifiedType() == InitTypeC.getUnqualifiedType()) || 1161 IsDerivedFrom(InitTypeC, DeclTypeC)) { 1162 CXXConstructorDecl *Constructor 1163 = PerformInitializationByConstructor(DeclType, &Init, 1, 1164 InitLoc, Init->getSourceRange(), 1165 InitEntity, 1166 DirectInit? IK_Direct : IK_Copy); 1167 return Constructor == 0; 1168 } 1169 1170 // -- Otherwise (i.e., for the remaining copy-initialization 1171 // cases), user-defined conversion sequences that can 1172 // convert from the source type to the destination type or 1173 // (when a conversion function is used) to a derived class 1174 // thereof are enumerated as described in 13.3.1.4, and the 1175 // best one is chosen through overload resolution 1176 // (13.3). If the conversion cannot be done or is 1177 // ambiguous, the initialization is ill-formed. The 1178 // function selected is called with the initializer 1179 // expression as its argument; if the function is a 1180 // constructor, the call initializes a temporary of the 1181 // destination type. 1182 // FIXME: We're pretending to do copy elision here; return to 1183 // this when we have ASTs for such things. 1184 if (!PerformImplicitConversion(Init, DeclType, "initializing")) 1185 return false; 1186 1187 if (InitEntity) 1188 return Diag(InitLoc, diag::err_cannot_initialize_decl) 1189 << InitEntity << (int)(Init->isLvalue(Context) == Expr::LV_Valid) 1190 << Init->getType() << Init->getSourceRange(); 1191 else 1192 return Diag(InitLoc, diag::err_cannot_initialize_decl_noname) 1193 << DeclType << (int)(Init->isLvalue(Context) == Expr::LV_Valid) 1194 << Init->getType() << Init->getSourceRange(); 1195 } 1196 1197 // C99 6.7.8p16. 1198 if (DeclType->isArrayType()) 1199 return Diag(Init->getLocStart(), diag::err_array_init_list_required) 1200 << Init->getSourceRange(); 1201 1202 return CheckSingleInitializer(Init, DeclType, DirectInit); 1203 } 1204 1205 bool hadError = CheckInitList(InitList, DeclType); 1206 Init = InitList; 1207 return hadError; 1208} 1209 1210/// GetNameForDeclarator - Determine the full declaration name for the 1211/// given Declarator. 1212DeclarationName Sema::GetNameForDeclarator(Declarator &D) { 1213 switch (D.getKind()) { 1214 case Declarator::DK_Abstract: 1215 assert(D.getIdentifier() == 0 && "abstract declarators have no name"); 1216 return DeclarationName(); 1217 1218 case Declarator::DK_Normal: 1219 assert (D.getIdentifier() != 0 && "normal declarators have an identifier"); 1220 return DeclarationName(D.getIdentifier()); 1221 1222 case Declarator::DK_Constructor: { 1223 QualType Ty = QualType::getFromOpaquePtr(D.getDeclaratorIdType()); 1224 Ty = Context.getCanonicalType(Ty); 1225 return Context.DeclarationNames.getCXXConstructorName(Ty); 1226 } 1227 1228 case Declarator::DK_Destructor: { 1229 QualType Ty = QualType::getFromOpaquePtr(D.getDeclaratorIdType()); 1230 Ty = Context.getCanonicalType(Ty); 1231 return Context.DeclarationNames.getCXXDestructorName(Ty); 1232 } 1233 1234 case Declarator::DK_Conversion: { 1235 // FIXME: We'd like to keep the non-canonical type for diagnostics! 1236 QualType Ty = QualType::getFromOpaquePtr(D.getDeclaratorIdType()); 1237 Ty = Context.getCanonicalType(Ty); 1238 return Context.DeclarationNames.getCXXConversionFunctionName(Ty); 1239 } 1240 1241 case Declarator::DK_Operator: 1242 assert(D.getIdentifier() == 0 && "operator names have no identifier"); 1243 return Context.DeclarationNames.getCXXOperatorName( 1244 D.getOverloadedOperator()); 1245 } 1246 1247 assert(false && "Unknown name kind"); 1248 return DeclarationName(); 1249} 1250 1251/// isNearlyMatchingFunction - Determine whether the C++ functions 1252/// Declaration and Definition are "nearly" matching. This heuristic 1253/// is used to improve diagnostics in the case where an out-of-line 1254/// function definition doesn't match any declaration within 1255/// the class or namespace. 1256static bool isNearlyMatchingFunction(ASTContext &Context, 1257 FunctionDecl *Declaration, 1258 FunctionDecl *Definition) { 1259 if (Declaration->param_size() != Definition->param_size()) 1260 return false; 1261 for (unsigned Idx = 0; Idx < Declaration->param_size(); ++Idx) { 1262 QualType DeclParamTy = Declaration->getParamDecl(Idx)->getType(); 1263 QualType DefParamTy = Definition->getParamDecl(Idx)->getType(); 1264 1265 DeclParamTy = Context.getCanonicalType(DeclParamTy.getNonReferenceType()); 1266 DefParamTy = Context.getCanonicalType(DefParamTy.getNonReferenceType()); 1267 if (DeclParamTy.getUnqualifiedType() != DefParamTy.getUnqualifiedType()) 1268 return false; 1269 } 1270 1271 return true; 1272} 1273 1274Sema::DeclTy * 1275Sema::ActOnDeclarator(Scope *S, Declarator &D, DeclTy *lastDecl, 1276 bool IsFunctionDefinition) { 1277 NamedDecl *LastDeclarator = dyn_cast_or_null<NamedDecl>((Decl *)lastDecl); 1278 DeclarationName Name = GetNameForDeclarator(D); 1279 1280 // All of these full declarators require an identifier. If it doesn't have 1281 // one, the ParsedFreeStandingDeclSpec action should be used. 1282 if (!Name) { 1283 if (!D.getInvalidType()) // Reject this if we think it is valid. 1284 Diag(D.getDeclSpec().getSourceRange().getBegin(), 1285 diag::err_declarator_need_ident) 1286 << D.getDeclSpec().getSourceRange() << D.getSourceRange(); 1287 return 0; 1288 } 1289 1290 // The scope passed in may not be a decl scope. Zip up the scope tree until 1291 // we find one that is. 1292 while ((S->getFlags() & Scope::DeclScope) == 0 || 1293 (S->getFlags() & Scope::TemplateParamScope) != 0) 1294 S = S->getParent(); 1295 1296 DeclContext *DC; 1297 NamedDecl *PrevDecl; 1298 NamedDecl *New; 1299 bool InvalidDecl = false; 1300 1301 // See if this is a redefinition of a variable in the same scope. 1302 if (!D.getCXXScopeSpec().isSet() && !D.getCXXScopeSpec().isInvalid()) { 1303 DC = CurContext; 1304 PrevDecl = LookupName(S, Name, LookupOrdinaryName, true, 1305 D.getDeclSpec().getStorageClassSpec() != 1306 DeclSpec::SCS_static, 1307 D.getIdentifierLoc()); 1308 } else { // Something like "int foo::x;" 1309 DC = static_cast<DeclContext*>(D.getCXXScopeSpec().getScopeRep()); 1310 PrevDecl = LookupQualifiedName(DC, Name, LookupOrdinaryName, true); 1311 1312 // C++ 7.3.1.2p2: 1313 // Members (including explicit specializations of templates) of a named 1314 // namespace can also be defined outside that namespace by explicit 1315 // qualification of the name being defined, provided that the entity being 1316 // defined was already declared in the namespace and the definition appears 1317 // after the point of declaration in a namespace that encloses the 1318 // declarations namespace. 1319 // 1320 // Note that we only check the context at this point. We don't yet 1321 // have enough information to make sure that PrevDecl is actually 1322 // the declaration we want to match. For example, given: 1323 // 1324 // class X { 1325 // void f(); 1326 // void f(float); 1327 // }; 1328 // 1329 // void X::f(int) { } // ill-formed 1330 // 1331 // In this case, PrevDecl will point to the overload set 1332 // containing the two f's declared in X, but neither of them 1333 // matches. 1334 1335 // First check whether we named the global scope. 1336 if (isa<TranslationUnitDecl>(DC)) { 1337 Diag(D.getIdentifierLoc(), diag::err_invalid_declarator_global_scope) 1338 << Name << D.getCXXScopeSpec().getRange(); 1339 } else if (!CurContext->Encloses(DC)) { 1340 // The qualifying scope doesn't enclose the original declaration. 1341 // Emit diagnostic based on current scope. 1342 SourceLocation L = D.getIdentifierLoc(); 1343 SourceRange R = D.getCXXScopeSpec().getRange(); 1344 if (isa<FunctionDecl>(CurContext)) 1345 Diag(L, diag::err_invalid_declarator_in_function) << Name << R; 1346 else 1347 Diag(L, diag::err_invalid_declarator_scope) 1348 << Name << cast<NamedDecl>(DC) << R; 1349 InvalidDecl = true; 1350 } 1351 } 1352 1353 if (PrevDecl && PrevDecl->isTemplateParameter()) { 1354 // Maybe we will complain about the shadowed template parameter. 1355 InvalidDecl = InvalidDecl 1356 || DiagnoseTemplateParameterShadow(D.getIdentifierLoc(), PrevDecl); 1357 // Just pretend that we didn't see the previous declaration. 1358 PrevDecl = 0; 1359 } 1360 1361 // In C++, the previous declaration we find might be a tag type 1362 // (class or enum). In this case, the new declaration will hide the 1363 // tag type. Note that this does does not apply if we're declaring a 1364 // typedef (C++ [dcl.typedef]p4). 1365 if (PrevDecl && PrevDecl->getIdentifierNamespace() == Decl::IDNS_Tag && 1366 D.getDeclSpec().getStorageClassSpec() != DeclSpec::SCS_typedef) 1367 PrevDecl = 0; 1368 1369 QualType R = GetTypeForDeclarator(D, S); 1370 assert(!R.isNull() && "GetTypeForDeclarator() returned null type"); 1371 1372 bool Redeclaration = false; 1373 if (D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_typedef) { 1374 New = ActOnTypedefDeclarator(S, D, DC, R, LastDeclarator, PrevDecl, 1375 InvalidDecl, Redeclaration); 1376 } else if (R.getTypePtr()->isFunctionType()) { 1377 New = ActOnFunctionDeclarator(S, D, DC, R, LastDeclarator, PrevDecl, 1378 IsFunctionDefinition, InvalidDecl, 1379 Redeclaration); 1380 } else { 1381 New = ActOnVariableDeclarator(S, D, DC, R, LastDeclarator, PrevDecl, 1382 InvalidDecl, Redeclaration); 1383 } 1384 1385 if (New == 0) 1386 return 0; 1387 1388 // Set the lexical context. If the declarator has a C++ scope specifier, the 1389 // lexical context will be different from the semantic context. 1390 New->setLexicalDeclContext(CurContext); 1391 1392 // If this has an identifier and is not an invalid redeclaration, 1393 // add it to the scope stack. 1394 if (Name && !(Redeclaration && InvalidDecl)) 1395 PushOnScopeChains(New, S); 1396 // If any semantic error occurred, mark the decl as invalid. 1397 if (D.getInvalidType() || InvalidDecl) 1398 New->setInvalidDecl(); 1399 1400 return New; 1401} 1402 1403NamedDecl* 1404Sema::ActOnTypedefDeclarator(Scope* S, Declarator& D, DeclContext* DC, 1405 QualType R, Decl* LastDeclarator, 1406 Decl* PrevDecl, bool& InvalidDecl, 1407 bool &Redeclaration) { 1408 // Typedef declarators cannot be qualified (C++ [dcl.meaning]p1). 1409 if (D.getCXXScopeSpec().isSet()) { 1410 Diag(D.getIdentifierLoc(), diag::err_qualified_typedef_declarator) 1411 << D.getCXXScopeSpec().getRange(); 1412 InvalidDecl = true; 1413 // Pretend we didn't see the scope specifier. 1414 DC = 0; 1415 } 1416 1417 // Check that there are no default arguments (C++ only). 1418 if (getLangOptions().CPlusPlus) 1419 CheckExtraCXXDefaultArguments(D); 1420 1421 TypedefDecl *NewTD = ParseTypedefDecl(S, D, R, LastDeclarator); 1422 if (!NewTD) return 0; 1423 1424 // Handle attributes prior to checking for duplicates in MergeVarDecl 1425 ProcessDeclAttributes(NewTD, D); 1426 // Merge the decl with the existing one if appropriate. If the decl is 1427 // in an outer scope, it isn't the same thing. 1428 if (PrevDecl && isDeclInScope(PrevDecl, DC, S)) { 1429 Redeclaration = true; 1430 if (MergeTypeDefDecl(NewTD, PrevDecl)) 1431 InvalidDecl = true; 1432 } 1433 1434 if (S->getFnParent() == 0) { 1435 // C99 6.7.7p2: If a typedef name specifies a variably modified type 1436 // then it shall have block scope. 1437 if (NewTD->getUnderlyingType()->isVariablyModifiedType()) { 1438 if (NewTD->getUnderlyingType()->isVariableArrayType()) 1439 Diag(D.getIdentifierLoc(), diag::err_vla_decl_in_file_scope); 1440 else 1441 Diag(D.getIdentifierLoc(), diag::err_vm_decl_in_file_scope); 1442 1443 InvalidDecl = true; 1444 } 1445 } 1446 return NewTD; 1447} 1448 1449NamedDecl* 1450Sema::ActOnVariableDeclarator(Scope* S, Declarator& D, DeclContext* DC, 1451 QualType R, Decl* LastDeclarator, 1452 Decl* PrevDecl, bool& InvalidDecl, 1453 bool &Redeclaration) { 1454 DeclarationName Name = GetNameForDeclarator(D); 1455 1456 // Check that there are no default arguments (C++ only). 1457 if (getLangOptions().CPlusPlus) 1458 CheckExtraCXXDefaultArguments(D); 1459 1460 if (R.getTypePtr()->isObjCInterfaceType()) { 1461 Diag(D.getIdentifierLoc(), diag::err_statically_allocated_object) 1462 << D.getIdentifier(); 1463 InvalidDecl = true; 1464 } 1465 1466 VarDecl *NewVD; 1467 VarDecl::StorageClass SC; 1468 switch (D.getDeclSpec().getStorageClassSpec()) { 1469 default: assert(0 && "Unknown storage class!"); 1470 case DeclSpec::SCS_unspecified: SC = VarDecl::None; break; 1471 case DeclSpec::SCS_extern: SC = VarDecl::Extern; break; 1472 case DeclSpec::SCS_static: SC = VarDecl::Static; break; 1473 case DeclSpec::SCS_auto: SC = VarDecl::Auto; break; 1474 case DeclSpec::SCS_register: SC = VarDecl::Register; break; 1475 case DeclSpec::SCS_private_extern: SC = VarDecl::PrivateExtern; break; 1476 case DeclSpec::SCS_mutable: 1477 // mutable can only appear on non-static class members, so it's always 1478 // an error here 1479 Diag(D.getIdentifierLoc(), diag::err_mutable_nonmember); 1480 InvalidDecl = true; 1481 SC = VarDecl::None; 1482 break; 1483 } 1484 1485 IdentifierInfo *II = Name.getAsIdentifierInfo(); 1486 if (!II) { 1487 Diag(D.getIdentifierLoc(), diag::err_bad_variable_name) 1488 << Name.getAsString(); 1489 return 0; 1490 } 1491 1492 if (DC->isRecord()) { 1493 // This is a static data member for a C++ class. 1494 NewVD = CXXClassVarDecl::Create(Context, cast<CXXRecordDecl>(DC), 1495 D.getIdentifierLoc(), II, 1496 R); 1497 } else { 1498 bool ThreadSpecified = D.getDeclSpec().isThreadSpecified(); 1499 if (S->getFnParent() == 0) { 1500 // C99 6.9p2: The storage-class specifiers auto and register shall not 1501 // appear in the declaration specifiers in an external declaration. 1502 if (SC == VarDecl::Auto || SC == VarDecl::Register) { 1503 Diag(D.getIdentifierLoc(), diag::err_typecheck_sclass_fscope); 1504 InvalidDecl = true; 1505 } 1506 } 1507 NewVD = VarDecl::Create(Context, DC, D.getIdentifierLoc(), 1508 II, R, SC, 1509 // FIXME: Move to DeclGroup... 1510 D.getDeclSpec().getSourceRange().getBegin()); 1511 NewVD->setThreadSpecified(ThreadSpecified); 1512 } 1513 NewVD->setNextDeclarator(LastDeclarator); 1514 1515 // Handle attributes prior to checking for duplicates in MergeVarDecl 1516 ProcessDeclAttributes(NewVD, D); 1517 1518 // Handle GNU asm-label extension (encoded as an attribute). 1519 if (Expr *E = (Expr*) D.getAsmLabel()) { 1520 // The parser guarantees this is a string. 1521 StringLiteral *SE = cast<StringLiteral>(E); 1522 NewVD->addAttr(new AsmLabelAttr(std::string(SE->getStrData(), 1523 SE->getByteLength()))); 1524 } 1525 1526 // Emit an error if an address space was applied to decl with local storage. 1527 // This includes arrays of objects with address space qualifiers, but not 1528 // automatic variables that point to other address spaces. 1529 // ISO/IEC TR 18037 S5.1.2 1530 if (NewVD->hasLocalStorage() && (NewVD->getType().getAddressSpace() != 0)) { 1531 Diag(D.getIdentifierLoc(), diag::err_as_qualified_auto_decl); 1532 InvalidDecl = true; 1533 } 1534 // Merge the decl with the existing one if appropriate. If the decl is 1535 // in an outer scope, it isn't the same thing. 1536 if (PrevDecl && isDeclInScope(PrevDecl, DC, S)) { 1537 if (isa<FieldDecl>(PrevDecl) && D.getCXXScopeSpec().isSet()) { 1538 // The user tried to define a non-static data member 1539 // out-of-line (C++ [dcl.meaning]p1). 1540 Diag(NewVD->getLocation(), diag::err_nonstatic_member_out_of_line) 1541 << D.getCXXScopeSpec().getRange(); 1542 NewVD->Destroy(Context); 1543 return 0; 1544 } 1545 1546 Redeclaration = true; 1547 if (MergeVarDecl(NewVD, PrevDecl)) 1548 InvalidDecl = true; 1549 1550 if (D.getCXXScopeSpec().isSet()) { 1551 // No previous declaration in the qualifying scope. 1552 Diag(D.getIdentifierLoc(), diag::err_typecheck_no_member) 1553 << Name << D.getCXXScopeSpec().getRange(); 1554 InvalidDecl = true; 1555 } 1556 } 1557 return NewVD; 1558} 1559 1560NamedDecl* 1561Sema::ActOnFunctionDeclarator(Scope* S, Declarator& D, DeclContext* DC, 1562 QualType R, Decl *LastDeclarator, 1563 Decl* PrevDecl, bool IsFunctionDefinition, 1564 bool& InvalidDecl, bool &Redeclaration) { 1565 assert(R.getTypePtr()->isFunctionType()); 1566 1567 DeclarationName Name = GetNameForDeclarator(D); 1568 FunctionDecl::StorageClass SC = FunctionDecl::None; 1569 switch (D.getDeclSpec().getStorageClassSpec()) { 1570 default: assert(0 && "Unknown storage class!"); 1571 case DeclSpec::SCS_auto: 1572 case DeclSpec::SCS_register: 1573 case DeclSpec::SCS_mutable: 1574 Diag(D.getIdentifierLoc(), diag::err_typecheck_sclass_func); 1575 InvalidDecl = true; 1576 break; 1577 case DeclSpec::SCS_unspecified: SC = FunctionDecl::None; break; 1578 case DeclSpec::SCS_extern: SC = FunctionDecl::Extern; break; 1579 case DeclSpec::SCS_static: SC = FunctionDecl::Static; break; 1580 case DeclSpec::SCS_private_extern: SC = FunctionDecl::PrivateExtern;break; 1581 } 1582 1583 bool isInline = D.getDeclSpec().isInlineSpecified(); 1584 // bool isVirtual = D.getDeclSpec().isVirtualSpecified(); 1585 bool isExplicit = D.getDeclSpec().isExplicitSpecified(); 1586 1587 FunctionDecl *NewFD; 1588 if (D.getKind() == Declarator::DK_Constructor) { 1589 // This is a C++ constructor declaration. 1590 assert(DC->isRecord() && 1591 "Constructors can only be declared in a member context"); 1592 1593 InvalidDecl = InvalidDecl || CheckConstructorDeclarator(D, R, SC); 1594 1595 // Create the new declaration 1596 NewFD = CXXConstructorDecl::Create(Context, 1597 cast<CXXRecordDecl>(DC), 1598 D.getIdentifierLoc(), Name, R, 1599 isExplicit, isInline, 1600 /*isImplicitlyDeclared=*/false); 1601 1602 if (InvalidDecl) 1603 NewFD->setInvalidDecl(); 1604 } else if (D.getKind() == Declarator::DK_Destructor) { 1605 // This is a C++ destructor declaration. 1606 if (DC->isRecord()) { 1607 InvalidDecl = InvalidDecl || CheckDestructorDeclarator(D, R, SC); 1608 1609 NewFD = CXXDestructorDecl::Create(Context, 1610 cast<CXXRecordDecl>(DC), 1611 D.getIdentifierLoc(), Name, R, 1612 isInline, 1613 /*isImplicitlyDeclared=*/false); 1614 1615 if (InvalidDecl) 1616 NewFD->setInvalidDecl(); 1617 } else { 1618 Diag(D.getIdentifierLoc(), diag::err_destructor_not_member); 1619 1620 // Create a FunctionDecl to satisfy the function definition parsing 1621 // code path. 1622 NewFD = FunctionDecl::Create(Context, DC, D.getIdentifierLoc(), 1623 Name, R, SC, isInline, 1624 // FIXME: Move to DeclGroup... 1625 D.getDeclSpec().getSourceRange().getBegin()); 1626 InvalidDecl = true; 1627 NewFD->setInvalidDecl(); 1628 } 1629 } else if (D.getKind() == Declarator::DK_Conversion) { 1630 if (!DC->isRecord()) { 1631 Diag(D.getIdentifierLoc(), 1632 diag::err_conv_function_not_member); 1633 return 0; 1634 } else { 1635 InvalidDecl = InvalidDecl || CheckConversionDeclarator(D, R, SC); 1636 1637 NewFD = CXXConversionDecl::Create(Context, cast<CXXRecordDecl>(DC), 1638 D.getIdentifierLoc(), Name, R, 1639 isInline, isExplicit); 1640 1641 if (InvalidDecl) 1642 NewFD->setInvalidDecl(); 1643 } 1644 } else if (DC->isRecord()) { 1645 // This is a C++ method declaration. 1646 NewFD = CXXMethodDecl::Create(Context, cast<CXXRecordDecl>(DC), 1647 D.getIdentifierLoc(), Name, R, 1648 (SC == FunctionDecl::Static), isInline); 1649 } else { 1650 NewFD = FunctionDecl::Create(Context, DC, 1651 D.getIdentifierLoc(), 1652 Name, R, SC, isInline, 1653 // FIXME: Move to DeclGroup... 1654 D.getDeclSpec().getSourceRange().getBegin()); 1655 } 1656 NewFD->setNextDeclarator(LastDeclarator); 1657 1658 // Set the lexical context. If the declarator has a C++ 1659 // scope specifier, the lexical context will be different 1660 // from the semantic context. 1661 NewFD->setLexicalDeclContext(CurContext); 1662 1663 // Handle GNU asm-label extension (encoded as an attribute). 1664 if (Expr *E = (Expr*) D.getAsmLabel()) { 1665 // The parser guarantees this is a string. 1666 StringLiteral *SE = cast<StringLiteral>(E); 1667 NewFD->addAttr(new AsmLabelAttr(std::string(SE->getStrData(), 1668 SE->getByteLength()))); 1669 } 1670 1671 // Copy the parameter declarations from the declarator D to 1672 // the function declaration NewFD, if they are available. 1673 if (D.getNumTypeObjects() > 0) { 1674 DeclaratorChunk::FunctionTypeInfo &FTI = D.getTypeObject(0).Fun; 1675 1676 // Create Decl objects for each parameter, adding them to the 1677 // FunctionDecl. 1678 llvm::SmallVector<ParmVarDecl*, 16> Params; 1679 1680 // Check for C99 6.7.5.3p10 - foo(void) is a non-varargs 1681 // function that takes no arguments, not a function that takes a 1682 // single void argument. 1683 // We let through "const void" here because Sema::GetTypeForDeclarator 1684 // already checks for that case. 1685 if (FTI.NumArgs == 1 && !FTI.isVariadic && FTI.ArgInfo[0].Ident == 0 && 1686 FTI.ArgInfo[0].Param && 1687 ((ParmVarDecl*)FTI.ArgInfo[0].Param)->getType()->isVoidType()) { 1688 // empty arg list, don't push any params. 1689 ParmVarDecl *Param = (ParmVarDecl*)FTI.ArgInfo[0].Param; 1690 1691 // In C++, the empty parameter-type-list must be spelled "void"; a 1692 // typedef of void is not permitted. 1693 if (getLangOptions().CPlusPlus && 1694 Param->getType().getUnqualifiedType() != Context.VoidTy) { 1695 Diag(Param->getLocation(), diag::ext_param_typedef_of_void); 1696 } 1697 } else if (FTI.NumArgs > 0 && FTI.ArgInfo[0].Param != 0) { 1698 for (unsigned i = 0, e = FTI.NumArgs; i != e; ++i) 1699 Params.push_back((ParmVarDecl *)FTI.ArgInfo[i].Param); 1700 } 1701 1702 NewFD->setParams(Context, &Params[0], Params.size()); 1703 } else if (R->getAsTypedefType()) { 1704 // When we're declaring a function with a typedef, as in the 1705 // following example, we'll need to synthesize (unnamed) 1706 // parameters for use in the declaration. 1707 // 1708 // @code 1709 // typedef void fn(int); 1710 // fn f; 1711 // @endcode 1712 const FunctionTypeProto *FT = R->getAsFunctionTypeProto(); 1713 if (!FT) { 1714 // This is a typedef of a function with no prototype, so we 1715 // don't need to do anything. 1716 } else if ((FT->getNumArgs() == 0) || 1717 (FT->getNumArgs() == 1 && !FT->isVariadic() && 1718 FT->getArgType(0)->isVoidType())) { 1719 // This is a zero-argument function. We don't need to do anything. 1720 } else { 1721 // Synthesize a parameter for each argument type. 1722 llvm::SmallVector<ParmVarDecl*, 16> Params; 1723 for (FunctionTypeProto::arg_type_iterator ArgType = FT->arg_type_begin(); 1724 ArgType != FT->arg_type_end(); ++ArgType) { 1725 ParmVarDecl *Param = ParmVarDecl::Create(Context, DC, 1726 SourceLocation(), 0, 1727 *ArgType, VarDecl::None, 1728 0); 1729 Param->setImplicit(); 1730 Params.push_back(Param); 1731 } 1732 1733 NewFD->setParams(Context, &Params[0], Params.size()); 1734 } 1735 } 1736 1737 if (CXXConstructorDecl *Constructor = dyn_cast<CXXConstructorDecl>(NewFD)) 1738 InvalidDecl = InvalidDecl || CheckConstructor(Constructor); 1739 else if (isa<CXXDestructorDecl>(NewFD)) { 1740 CXXRecordDecl *Record = cast<CXXRecordDecl>(NewFD->getParent()); 1741 Record->setUserDeclaredDestructor(true); 1742 // C++ [class]p4: A POD-struct is an aggregate class that has [...] no 1743 // user-defined destructor. 1744 Record->setPOD(false); 1745 } else if (CXXConversionDecl *Conversion = 1746 dyn_cast<CXXConversionDecl>(NewFD)) 1747 ActOnConversionDeclarator(Conversion); 1748 1749 // Extra checking for C++ overloaded operators (C++ [over.oper]). 1750 if (NewFD->isOverloadedOperator() && 1751 CheckOverloadedOperatorDeclaration(NewFD)) 1752 NewFD->setInvalidDecl(); 1753 1754 // Merge the decl with the existing one if appropriate. Since C functions 1755 // are in a flat namespace, make sure we consider decls in outer scopes. 1756 bool OverloadableAttrRequired = false; 1757 if (PrevDecl && 1758 (!getLangOptions().CPlusPlus||isDeclInScope(PrevDecl, DC, S))) { 1759 // Determine whether NewFD is an overload of PrevDecl or 1760 // a declaration that requires merging. If it's an overload, 1761 // there's no more work to do here; we'll just add the new 1762 // function to the scope. 1763 OverloadedFunctionDecl::function_iterator MatchedDecl; 1764 1765 if (!getLangOptions().CPlusPlus && 1766 AllowOverloadingOfFunction(PrevDecl, Context)) 1767 OverloadableAttrRequired = true; 1768 1769 if (!AllowOverloadingOfFunction(PrevDecl, Context) || 1770 !IsOverload(NewFD, PrevDecl, MatchedDecl)) { 1771 Redeclaration = true; 1772 Decl *OldDecl = PrevDecl; 1773 1774 // If PrevDecl was an overloaded function, extract the 1775 // FunctionDecl that matched. 1776 if (isa<OverloadedFunctionDecl>(PrevDecl)) 1777 OldDecl = *MatchedDecl; 1778 1779 // NewFD and PrevDecl represent declarations that need to be 1780 // merged. 1781 if (MergeFunctionDecl(NewFD, OldDecl)) 1782 InvalidDecl = true; 1783 1784 if (!InvalidDecl) { 1785 NewFD->setPreviousDeclaration(cast<FunctionDecl>(OldDecl)); 1786 1787 // An out-of-line member function declaration must also be a 1788 // definition (C++ [dcl.meaning]p1). 1789 if (!IsFunctionDefinition && D.getCXXScopeSpec().isSet() && 1790 !InvalidDecl) { 1791 Diag(NewFD->getLocation(), diag::err_out_of_line_declaration) 1792 << D.getCXXScopeSpec().getRange(); 1793 NewFD->setInvalidDecl(); 1794 } 1795 } 1796 } 1797 } 1798 1799 if (D.getCXXScopeSpec().isSet() && 1800 (!PrevDecl || !Redeclaration)) { 1801 // The user tried to provide an out-of-line definition for a 1802 // function that is a member of a class or namespace, but there 1803 // was no such member function declared (C++ [class.mfct]p2, 1804 // C++ [namespace.memdef]p2). For example: 1805 // 1806 // class X { 1807 // void f() const; 1808 // }; 1809 // 1810 // void X::f() { } // ill-formed 1811 // 1812 // Complain about this problem, and attempt to suggest close 1813 // matches (e.g., those that differ only in cv-qualifiers and 1814 // whether the parameter types are references). 1815 Diag(D.getIdentifierLoc(), diag::err_member_def_does_not_match) 1816 << cast<NamedDecl>(DC) << D.getCXXScopeSpec().getRange(); 1817 InvalidDecl = true; 1818 1819 LookupResult Prev = LookupQualifiedName(DC, Name, LookupOrdinaryName, 1820 true); 1821 assert(!Prev.isAmbiguous() && 1822 "Cannot have an ambiguity in previous-declaration lookup"); 1823 for (LookupResult::iterator Func = Prev.begin(), FuncEnd = Prev.end(); 1824 Func != FuncEnd; ++Func) { 1825 if (isa<FunctionDecl>(*Func) && 1826 isNearlyMatchingFunction(Context, cast<FunctionDecl>(*Func), NewFD)) 1827 Diag((*Func)->getLocation(), diag::note_member_def_close_match); 1828 } 1829 1830 PrevDecl = 0; 1831 } 1832 1833 // Handle attributes. We need to have merged decls when handling attributes 1834 // (for example to check for conflicts, etc). 1835 ProcessDeclAttributes(NewFD, D); 1836 AddKnownFunctionAttributes(NewFD); 1837 1838 if (OverloadableAttrRequired && !NewFD->getAttr<OverloadableAttr>()) { 1839 // If a function name is overloadable in C, then every function 1840 // with that name must be marked "overloadable". 1841 Diag(NewFD->getLocation(), diag::err_attribute_overloadable_missing) 1842 << Redeclaration << NewFD; 1843 if (PrevDecl) 1844 Diag(PrevDecl->getLocation(), 1845 diag::note_attribute_overloadable_prev_overload); 1846 NewFD->addAttr(new OverloadableAttr); 1847 } 1848 1849 if (getLangOptions().CPlusPlus) { 1850 // In C++, check default arguments now that we have merged decls. Unless 1851 // the lexical context is the class, because in this case this is done 1852 // during delayed parsing anyway. 1853 if (!CurContext->isRecord()) 1854 CheckCXXDefaultArguments(NewFD); 1855 1856 // An out-of-line member function declaration must also be a 1857 // definition (C++ [dcl.meaning]p1). 1858 if (!IsFunctionDefinition && D.getCXXScopeSpec().isSet() && !InvalidDecl) { 1859 Diag(NewFD->getLocation(), diag::err_out_of_line_declaration) 1860 << D.getCXXScopeSpec().getRange(); 1861 InvalidDecl = true; 1862 } 1863 } 1864 return NewFD; 1865} 1866 1867void Sema::InitializerElementNotConstant(const Expr *Init) { 1868 Diag(Init->getExprLoc(), diag::err_init_element_not_constant) 1869 << Init->getSourceRange(); 1870} 1871 1872bool Sema::CheckAddressConstantExpressionLValue(const Expr* Init) { 1873 switch (Init->getStmtClass()) { 1874 default: 1875 InitializerElementNotConstant(Init); 1876 return true; 1877 case Expr::ParenExprClass: { 1878 const ParenExpr* PE = cast<ParenExpr>(Init); 1879 return CheckAddressConstantExpressionLValue(PE->getSubExpr()); 1880 } 1881 case Expr::CompoundLiteralExprClass: 1882 return cast<CompoundLiteralExpr>(Init)->isFileScope(); 1883 case Expr::DeclRefExprClass: 1884 case Expr::QualifiedDeclRefExprClass: { 1885 const Decl *D = cast<DeclRefExpr>(Init)->getDecl(); 1886 if (const VarDecl *VD = dyn_cast<VarDecl>(D)) { 1887 if (VD->hasGlobalStorage()) 1888 return false; 1889 InitializerElementNotConstant(Init); 1890 return true; 1891 } 1892 if (isa<FunctionDecl>(D)) 1893 return false; 1894 InitializerElementNotConstant(Init); 1895 return true; 1896 } 1897 case Expr::MemberExprClass: { 1898 const MemberExpr *M = cast<MemberExpr>(Init); 1899 if (M->isArrow()) 1900 return CheckAddressConstantExpression(M->getBase()); 1901 return CheckAddressConstantExpressionLValue(M->getBase()); 1902 } 1903 case Expr::ArraySubscriptExprClass: { 1904 // FIXME: Should we pedwarn for "x[0+0]" (where x is a pointer)? 1905 const ArraySubscriptExpr *ASE = cast<ArraySubscriptExpr>(Init); 1906 return CheckAddressConstantExpression(ASE->getBase()) || 1907 CheckArithmeticConstantExpression(ASE->getIdx()); 1908 } 1909 case Expr::StringLiteralClass: 1910 case Expr::PredefinedExprClass: 1911 return false; 1912 case Expr::UnaryOperatorClass: { 1913 const UnaryOperator *Exp = cast<UnaryOperator>(Init); 1914 1915 // C99 6.6p9 1916 if (Exp->getOpcode() == UnaryOperator::Deref) 1917 return CheckAddressConstantExpression(Exp->getSubExpr()); 1918 1919 InitializerElementNotConstant(Init); 1920 return true; 1921 } 1922 } 1923} 1924 1925bool Sema::CheckAddressConstantExpression(const Expr* Init) { 1926 switch (Init->getStmtClass()) { 1927 default: 1928 InitializerElementNotConstant(Init); 1929 return true; 1930 case Expr::ParenExprClass: 1931 return CheckAddressConstantExpression(cast<ParenExpr>(Init)->getSubExpr()); 1932 case Expr::StringLiteralClass: 1933 case Expr::ObjCStringLiteralClass: 1934 return false; 1935 case Expr::CallExprClass: 1936 case Expr::CXXOperatorCallExprClass: 1937 // __builtin___CFStringMakeConstantString is a valid constant l-value. 1938 if (cast<CallExpr>(Init)->isBuiltinCall(Context) == 1939 Builtin::BI__builtin___CFStringMakeConstantString) 1940 return false; 1941 1942 InitializerElementNotConstant(Init); 1943 return true; 1944 1945 case Expr::UnaryOperatorClass: { 1946 const UnaryOperator *Exp = cast<UnaryOperator>(Init); 1947 1948 // C99 6.6p9 1949 if (Exp->getOpcode() == UnaryOperator::AddrOf) 1950 return CheckAddressConstantExpressionLValue(Exp->getSubExpr()); 1951 1952 if (Exp->getOpcode() == UnaryOperator::Extension) 1953 return CheckAddressConstantExpression(Exp->getSubExpr()); 1954 1955 InitializerElementNotConstant(Init); 1956 return true; 1957 } 1958 case Expr::BinaryOperatorClass: { 1959 // FIXME: Should we pedwarn for expressions like "a + 1 + 2"? 1960 const BinaryOperator *Exp = cast<BinaryOperator>(Init); 1961 1962 Expr *PExp = Exp->getLHS(); 1963 Expr *IExp = Exp->getRHS(); 1964 if (IExp->getType()->isPointerType()) 1965 std::swap(PExp, IExp); 1966 1967 // FIXME: Should we pedwarn if IExp isn't an integer constant expression? 1968 return CheckAddressConstantExpression(PExp) || 1969 CheckArithmeticConstantExpression(IExp); 1970 } 1971 case Expr::ImplicitCastExprClass: 1972 case Expr::CStyleCastExprClass: { 1973 const Expr* SubExpr = cast<CastExpr>(Init)->getSubExpr(); 1974 if (Init->getStmtClass() == Expr::ImplicitCastExprClass) { 1975 // Check for implicit promotion 1976 if (SubExpr->getType()->isFunctionType() || 1977 SubExpr->getType()->isArrayType()) 1978 return CheckAddressConstantExpressionLValue(SubExpr); 1979 } 1980 1981 // Check for pointer->pointer cast 1982 if (SubExpr->getType()->isPointerType()) 1983 return CheckAddressConstantExpression(SubExpr); 1984 1985 if (SubExpr->getType()->isIntegralType()) { 1986 // Check for the special-case of a pointer->int->pointer cast; 1987 // this isn't standard, but some code requires it. See 1988 // PR2720 for an example. 1989 if (const CastExpr* SubCast = dyn_cast<CastExpr>(SubExpr)) { 1990 if (SubCast->getSubExpr()->getType()->isPointerType()) { 1991 unsigned IntWidth = Context.getIntWidth(SubCast->getType()); 1992 unsigned PointerWidth = Context.getTypeSize(Context.VoidPtrTy); 1993 if (IntWidth >= PointerWidth) { 1994 return CheckAddressConstantExpression(SubCast->getSubExpr()); 1995 } 1996 } 1997 } 1998 } 1999 if (SubExpr->getType()->isArithmeticType()) { 2000 return CheckArithmeticConstantExpression(SubExpr); 2001 } 2002 2003 InitializerElementNotConstant(Init); 2004 return true; 2005 } 2006 case Expr::ConditionalOperatorClass: { 2007 // FIXME: Should we pedwarn here? 2008 const ConditionalOperator *Exp = cast<ConditionalOperator>(Init); 2009 if (!Exp->getCond()->getType()->isArithmeticType()) { 2010 InitializerElementNotConstant(Init); 2011 return true; 2012 } 2013 if (CheckArithmeticConstantExpression(Exp->getCond())) 2014 return true; 2015 if (Exp->getLHS() && 2016 CheckAddressConstantExpression(Exp->getLHS())) 2017 return true; 2018 return CheckAddressConstantExpression(Exp->getRHS()); 2019 } 2020 case Expr::AddrLabelExprClass: 2021 return false; 2022 } 2023} 2024 2025static const Expr* FindExpressionBaseAddress(const Expr* E); 2026 2027static const Expr* FindExpressionBaseAddressLValue(const Expr* E) { 2028 switch (E->getStmtClass()) { 2029 default: 2030 return E; 2031 case Expr::ParenExprClass: { 2032 const ParenExpr* PE = cast<ParenExpr>(E); 2033 return FindExpressionBaseAddressLValue(PE->getSubExpr()); 2034 } 2035 case Expr::MemberExprClass: { 2036 const MemberExpr *M = cast<MemberExpr>(E); 2037 if (M->isArrow()) 2038 return FindExpressionBaseAddress(M->getBase()); 2039 return FindExpressionBaseAddressLValue(M->getBase()); 2040 } 2041 case Expr::ArraySubscriptExprClass: { 2042 const ArraySubscriptExpr *ASE = cast<ArraySubscriptExpr>(E); 2043 return FindExpressionBaseAddress(ASE->getBase()); 2044 } 2045 case Expr::UnaryOperatorClass: { 2046 const UnaryOperator *Exp = cast<UnaryOperator>(E); 2047 2048 if (Exp->getOpcode() == UnaryOperator::Deref) 2049 return FindExpressionBaseAddress(Exp->getSubExpr()); 2050 2051 return E; 2052 } 2053 } 2054} 2055 2056static const Expr* FindExpressionBaseAddress(const Expr* E) { 2057 switch (E->getStmtClass()) { 2058 default: 2059 return E; 2060 case Expr::ParenExprClass: { 2061 const ParenExpr* PE = cast<ParenExpr>(E); 2062 return FindExpressionBaseAddress(PE->getSubExpr()); 2063 } 2064 case Expr::UnaryOperatorClass: { 2065 const UnaryOperator *Exp = cast<UnaryOperator>(E); 2066 2067 // C99 6.6p9 2068 if (Exp->getOpcode() == UnaryOperator::AddrOf) 2069 return FindExpressionBaseAddressLValue(Exp->getSubExpr()); 2070 2071 if (Exp->getOpcode() == UnaryOperator::Extension) 2072 return FindExpressionBaseAddress(Exp->getSubExpr()); 2073 2074 return E; 2075 } 2076 case Expr::BinaryOperatorClass: { 2077 const BinaryOperator *Exp = cast<BinaryOperator>(E); 2078 2079 Expr *PExp = Exp->getLHS(); 2080 Expr *IExp = Exp->getRHS(); 2081 if (IExp->getType()->isPointerType()) 2082 std::swap(PExp, IExp); 2083 2084 return FindExpressionBaseAddress(PExp); 2085 } 2086 case Expr::ImplicitCastExprClass: { 2087 const Expr* SubExpr = cast<ImplicitCastExpr>(E)->getSubExpr(); 2088 2089 // Check for implicit promotion 2090 if (SubExpr->getType()->isFunctionType() || 2091 SubExpr->getType()->isArrayType()) 2092 return FindExpressionBaseAddressLValue(SubExpr); 2093 2094 // Check for pointer->pointer cast 2095 if (SubExpr->getType()->isPointerType()) 2096 return FindExpressionBaseAddress(SubExpr); 2097 2098 // We assume that we have an arithmetic expression here; 2099 // if we don't, we'll figure it out later 2100 return 0; 2101 } 2102 case Expr::CStyleCastExprClass: { 2103 const Expr* SubExpr = cast<CastExpr>(E)->getSubExpr(); 2104 2105 // Check for pointer->pointer cast 2106 if (SubExpr->getType()->isPointerType()) 2107 return FindExpressionBaseAddress(SubExpr); 2108 2109 // We assume that we have an arithmetic expression here; 2110 // if we don't, we'll figure it out later 2111 return 0; 2112 } 2113 } 2114} 2115 2116bool Sema::CheckArithmeticConstantExpression(const Expr* Init) { 2117 switch (Init->getStmtClass()) { 2118 default: 2119 InitializerElementNotConstant(Init); 2120 return true; 2121 case Expr::ParenExprClass: { 2122 const ParenExpr* PE = cast<ParenExpr>(Init); 2123 return CheckArithmeticConstantExpression(PE->getSubExpr()); 2124 } 2125 case Expr::FloatingLiteralClass: 2126 case Expr::IntegerLiteralClass: 2127 case Expr::CharacterLiteralClass: 2128 case Expr::ImaginaryLiteralClass: 2129 case Expr::TypesCompatibleExprClass: 2130 case Expr::CXXBoolLiteralExprClass: 2131 return false; 2132 case Expr::CallExprClass: 2133 case Expr::CXXOperatorCallExprClass: { 2134 const CallExpr *CE = cast<CallExpr>(Init); 2135 2136 // Allow any constant foldable calls to builtins. 2137 if (CE->isBuiltinCall(Context) && CE->isEvaluatable(Context)) 2138 return false; 2139 2140 InitializerElementNotConstant(Init); 2141 return true; 2142 } 2143 case Expr::DeclRefExprClass: 2144 case Expr::QualifiedDeclRefExprClass: { 2145 const Decl *D = cast<DeclRefExpr>(Init)->getDecl(); 2146 if (isa<EnumConstantDecl>(D)) 2147 return false; 2148 InitializerElementNotConstant(Init); 2149 return true; 2150 } 2151 case Expr::CompoundLiteralExprClass: 2152 // Allow "(vector type){2,4}"; normal C constraints don't allow this, 2153 // but vectors are allowed to be magic. 2154 if (Init->getType()->isVectorType()) 2155 return false; 2156 InitializerElementNotConstant(Init); 2157 return true; 2158 case Expr::UnaryOperatorClass: { 2159 const UnaryOperator *Exp = cast<UnaryOperator>(Init); 2160 2161 switch (Exp->getOpcode()) { 2162 // Address, indirect, pre/post inc/dec, etc are not valid constant exprs. 2163 // See C99 6.6p3. 2164 default: 2165 InitializerElementNotConstant(Init); 2166 return true; 2167 case UnaryOperator::OffsetOf: 2168 if (Exp->getSubExpr()->getType()->isConstantSizeType()) 2169 return false; 2170 InitializerElementNotConstant(Init); 2171 return true; 2172 case UnaryOperator::Extension: 2173 case UnaryOperator::LNot: 2174 case UnaryOperator::Plus: 2175 case UnaryOperator::Minus: 2176 case UnaryOperator::Not: 2177 return CheckArithmeticConstantExpression(Exp->getSubExpr()); 2178 } 2179 } 2180 case Expr::SizeOfAlignOfExprClass: { 2181 const SizeOfAlignOfExpr *Exp = cast<SizeOfAlignOfExpr>(Init); 2182 // Special check for void types, which are allowed as an extension 2183 if (Exp->getTypeOfArgument()->isVoidType()) 2184 return false; 2185 // alignof always evaluates to a constant. 2186 // FIXME: is sizeof(int[3.0]) a constant expression? 2187 if (Exp->isSizeOf() && !Exp->getTypeOfArgument()->isConstantSizeType()) { 2188 InitializerElementNotConstant(Init); 2189 return true; 2190 } 2191 return false; 2192 } 2193 case Expr::BinaryOperatorClass: { 2194 const BinaryOperator *Exp = cast<BinaryOperator>(Init); 2195 2196 if (Exp->getLHS()->getType()->isArithmeticType() && 2197 Exp->getRHS()->getType()->isArithmeticType()) { 2198 return CheckArithmeticConstantExpression(Exp->getLHS()) || 2199 CheckArithmeticConstantExpression(Exp->getRHS()); 2200 } 2201 2202 if (Exp->getLHS()->getType()->isPointerType() && 2203 Exp->getRHS()->getType()->isPointerType()) { 2204 const Expr* LHSBase = FindExpressionBaseAddress(Exp->getLHS()); 2205 const Expr* RHSBase = FindExpressionBaseAddress(Exp->getRHS()); 2206 2207 // Only allow a null (constant integer) base; we could 2208 // allow some additional cases if necessary, but this 2209 // is sufficient to cover offsetof-like constructs. 2210 if (!LHSBase && !RHSBase) { 2211 return CheckAddressConstantExpression(Exp->getLHS()) || 2212 CheckAddressConstantExpression(Exp->getRHS()); 2213 } 2214 } 2215 2216 InitializerElementNotConstant(Init); 2217 return true; 2218 } 2219 case Expr::ImplicitCastExprClass: 2220 case Expr::CStyleCastExprClass: { 2221 const CastExpr *CE = cast<CastExpr>(Init); 2222 const Expr *SubExpr = CE->getSubExpr(); 2223 2224 if (SubExpr->getType()->isArithmeticType()) 2225 return CheckArithmeticConstantExpression(SubExpr); 2226 2227 if (SubExpr->getType()->isPointerType()) { 2228 const Expr* Base = FindExpressionBaseAddress(SubExpr); 2229 if (Base) { 2230 // the cast is only valid if done to a wide enough type 2231 if (Context.getTypeSize(CE->getType()) >= 2232 Context.getTypeSize(SubExpr->getType())) 2233 return false; 2234 } else { 2235 // If the pointer has a null base, this is an offsetof-like construct 2236 return CheckAddressConstantExpression(SubExpr); 2237 } 2238 } 2239 2240 InitializerElementNotConstant(Init); 2241 return true; 2242 } 2243 case Expr::ConditionalOperatorClass: { 2244 const ConditionalOperator *Exp = cast<ConditionalOperator>(Init); 2245 2246 // If GNU extensions are disabled, we require all operands to be arithmetic 2247 // constant expressions. 2248 if (getLangOptions().NoExtensions) { 2249 return CheckArithmeticConstantExpression(Exp->getCond()) || 2250 (Exp->getLHS() && CheckArithmeticConstantExpression(Exp->getLHS())) || 2251 CheckArithmeticConstantExpression(Exp->getRHS()); 2252 } 2253 2254 // Otherwise, we have to emulate some of the behavior of fold here. 2255 // Basically GCC treats things like "4 ? 1 : somefunc()" as a constant 2256 // because it can constant fold things away. To retain compatibility with 2257 // GCC code, we see if we can fold the condition to a constant (which we 2258 // should always be able to do in theory). If so, we only require the 2259 // specified arm of the conditional to be a constant. This is a horrible 2260 // hack, but is require by real world code that uses __builtin_constant_p. 2261 Expr::EvalResult EvalResult; 2262 if (!Exp->getCond()->Evaluate(EvalResult, Context) || 2263 EvalResult.HasSideEffects) { 2264 // If Evaluate couldn't fold it, CheckArithmeticConstantExpression 2265 // won't be able to either. Use it to emit the diagnostic though. 2266 bool Res = CheckArithmeticConstantExpression(Exp->getCond()); 2267 assert(Res && "Evaluate couldn't evaluate this constant?"); 2268 return Res; 2269 } 2270 2271 // Verify that the side following the condition is also a constant. 2272 const Expr *TrueSide = Exp->getLHS(), *FalseSide = Exp->getRHS(); 2273 if (EvalResult.Val.getInt() == 0) 2274 std::swap(TrueSide, FalseSide); 2275 2276 if (TrueSide && CheckArithmeticConstantExpression(TrueSide)) 2277 return true; 2278 2279 // Okay, the evaluated side evaluates to a constant, so we accept this. 2280 // Check to see if the other side is obviously not a constant. If so, 2281 // emit a warning that this is a GNU extension. 2282 if (FalseSide && !FalseSide->isEvaluatable(Context)) 2283 Diag(Init->getExprLoc(), 2284 diag::ext_typecheck_expression_not_constant_but_accepted) 2285 << FalseSide->getSourceRange(); 2286 return false; 2287 } 2288 } 2289} 2290 2291bool Sema::CheckForConstantInitializer(Expr *Init, QualType DclT) { 2292 if (DesignatedInitExpr *DIE = dyn_cast<DesignatedInitExpr>(Init)) 2293 Init = DIE->getInit(); 2294 2295 Init = Init->IgnoreParens(); 2296 2297 if (Init->isEvaluatable(Context)) 2298 return false; 2299 2300 // Look through CXXDefaultArgExprs; they have no meaning in this context. 2301 if (CXXDefaultArgExpr* DAE = dyn_cast<CXXDefaultArgExpr>(Init)) 2302 return CheckForConstantInitializer(DAE->getExpr(), DclT); 2303 2304 if (CompoundLiteralExpr *e = dyn_cast<CompoundLiteralExpr>(Init)) 2305 return CheckForConstantInitializer(e->getInitializer(), DclT); 2306 2307 if (isa<ImplicitValueInitExpr>(Init)) { 2308 // FIXME: In C++, check for non-POD types. 2309 return false; 2310 } 2311 2312 if (InitListExpr *Exp = dyn_cast<InitListExpr>(Init)) { 2313 unsigned numInits = Exp->getNumInits(); 2314 for (unsigned i = 0; i < numInits; i++) { 2315 // FIXME: Need to get the type of the declaration for C++, 2316 // because it could be a reference? 2317 2318 if (CheckForConstantInitializer(Exp->getInit(i), 2319 Exp->getInit(i)->getType())) 2320 return true; 2321 } 2322 return false; 2323 } 2324 2325 // FIXME: We can probably remove some of this code below, now that 2326 // Expr::Evaluate is doing the heavy lifting for scalars. 2327 2328 if (Init->isNullPointerConstant(Context)) 2329 return false; 2330 if (Init->getType()->isArithmeticType()) { 2331 QualType InitTy = Context.getCanonicalType(Init->getType()) 2332 .getUnqualifiedType(); 2333 if (InitTy == Context.BoolTy) { 2334 // Special handling for pointers implicitly cast to bool; 2335 // (e.g. "_Bool rr = &rr;"). This is only legal at the top level. 2336 if (ImplicitCastExpr* ICE = dyn_cast<ImplicitCastExpr>(Init)) { 2337 Expr* SubE = ICE->getSubExpr(); 2338 if (SubE->getType()->isPointerType() || 2339 SubE->getType()->isArrayType() || 2340 SubE->getType()->isFunctionType()) { 2341 return CheckAddressConstantExpression(Init); 2342 } 2343 } 2344 } else if (InitTy->isIntegralType()) { 2345 Expr* SubE = 0; 2346 if (CastExpr* CE = dyn_cast<CastExpr>(Init)) 2347 SubE = CE->getSubExpr(); 2348 // Special check for pointer cast to int; we allow as an extension 2349 // an address constant cast to an integer if the integer 2350 // is of an appropriate width (this sort of code is apparently used 2351 // in some places). 2352 // FIXME: Add pedwarn? 2353 // FIXME: Don't allow bitfields here! Need the FieldDecl for that. 2354 if (SubE && (SubE->getType()->isPointerType() || 2355 SubE->getType()->isArrayType() || 2356 SubE->getType()->isFunctionType())) { 2357 unsigned IntWidth = Context.getTypeSize(Init->getType()); 2358 unsigned PointerWidth = Context.getTypeSize(Context.VoidPtrTy); 2359 if (IntWidth >= PointerWidth) 2360 return CheckAddressConstantExpression(Init); 2361 } 2362 } 2363 2364 return CheckArithmeticConstantExpression(Init); 2365 } 2366 2367 if (Init->getType()->isPointerType()) 2368 return CheckAddressConstantExpression(Init); 2369 2370 // An array type at the top level that isn't an init-list must 2371 // be a string literal 2372 if (Init->getType()->isArrayType()) 2373 return false; 2374 2375 if (Init->getType()->isFunctionType()) 2376 return false; 2377 2378 // Allow block exprs at top level. 2379 if (Init->getType()->isBlockPointerType()) 2380 return false; 2381 2382 // GCC cast to union extension 2383 // note: the validity of the cast expr is checked by CheckCastTypes() 2384 if (CastExpr *C = dyn_cast<CastExpr>(Init)) { 2385 QualType T = C->getType(); 2386 return T->isUnionType() && CheckForConstantInitializer(C->getSubExpr(), T); 2387 } 2388 2389 InitializerElementNotConstant(Init); 2390 return true; 2391} 2392 2393void Sema::AddInitializerToDecl(DeclTy *dcl, ExprArg init) { 2394 AddInitializerToDecl(dcl, move(init), /*DirectInit=*/false); 2395} 2396 2397/// AddInitializerToDecl - Adds the initializer Init to the 2398/// declaration dcl. If DirectInit is true, this is C++ direct 2399/// initialization rather than copy initialization. 2400void Sema::AddInitializerToDecl(DeclTy *dcl, ExprArg init, bool DirectInit) { 2401 Decl *RealDecl = static_cast<Decl *>(dcl); 2402 Expr *Init = static_cast<Expr *>(init.release()); 2403 assert(Init && "missing initializer"); 2404 2405 // If there is no declaration, there was an error parsing it. Just ignore 2406 // the initializer. 2407 if (RealDecl == 0) { 2408 Init->Destroy(Context); 2409 return; 2410 } 2411 2412 VarDecl *VDecl = dyn_cast<VarDecl>(RealDecl); 2413 if (!VDecl) { 2414 Diag(RealDecl->getLocation(), diag::err_illegal_initializer); 2415 RealDecl->setInvalidDecl(); 2416 return; 2417 } 2418 // Get the decls type and save a reference for later, since 2419 // CheckInitializerTypes may change it. 2420 QualType DclT = VDecl->getType(), SavT = DclT; 2421 if (VDecl->isBlockVarDecl()) { 2422 VarDecl::StorageClass SC = VDecl->getStorageClass(); 2423 if (SC == VarDecl::Extern) { // C99 6.7.8p5 2424 Diag(VDecl->getLocation(), diag::err_block_extern_cant_init); 2425 VDecl->setInvalidDecl(); 2426 } else if (!VDecl->isInvalidDecl()) { 2427 if (CheckInitializerTypes(Init, DclT, VDecl->getLocation(), 2428 VDecl->getDeclName(), DirectInit)) 2429 VDecl->setInvalidDecl(); 2430 2431 // C++ 3.6.2p2, allow dynamic initialization of static initializers. 2432 if (!getLangOptions().CPlusPlus) { 2433 if (SC == VarDecl::Static) // C99 6.7.8p4. 2434 CheckForConstantInitializer(Init, DclT); 2435 } 2436 } 2437 } else if (VDecl->isFileVarDecl()) { 2438 if (VDecl->getStorageClass() == VarDecl::Extern) 2439 Diag(VDecl->getLocation(), diag::warn_extern_init); 2440 if (!VDecl->isInvalidDecl()) 2441 if (CheckInitializerTypes(Init, DclT, VDecl->getLocation(), 2442 VDecl->getDeclName(), DirectInit)) 2443 VDecl->setInvalidDecl(); 2444 2445 // C++ 3.6.2p2, allow dynamic initialization of static initializers. 2446 if (!getLangOptions().CPlusPlus) { 2447 // C99 6.7.8p4. All file scoped initializers need to be constant. 2448 CheckForConstantInitializer(Init, DclT); 2449 } 2450 } 2451 // If the type changed, it means we had an incomplete type that was 2452 // completed by the initializer. For example: 2453 // int ary[] = { 1, 3, 5 }; 2454 // "ary" transitions from a VariableArrayType to a ConstantArrayType. 2455 if (!VDecl->isInvalidDecl() && (DclT != SavT)) { 2456 VDecl->setType(DclT); 2457 Init->setType(DclT); 2458 } 2459 2460 // Attach the initializer to the decl. 2461 VDecl->setInit(Init); 2462 return; 2463} 2464 2465void Sema::ActOnUninitializedDecl(DeclTy *dcl) { 2466 Decl *RealDecl = static_cast<Decl *>(dcl); 2467 2468 // If there is no declaration, there was an error parsing it. Just ignore it. 2469 if (RealDecl == 0) 2470 return; 2471 2472 if (VarDecl *Var = dyn_cast<VarDecl>(RealDecl)) { 2473 QualType Type = Var->getType(); 2474 // C++ [dcl.init.ref]p3: 2475 // The initializer can be omitted for a reference only in a 2476 // parameter declaration (8.3.5), in the declaration of a 2477 // function return type, in the declaration of a class member 2478 // within its class declaration (9.2), and where the extern 2479 // specifier is explicitly used. 2480 if (Type->isReferenceType() && 2481 Var->getStorageClass() != VarDecl::Extern && 2482 Var->getStorageClass() != VarDecl::PrivateExtern) { 2483 Diag(Var->getLocation(), diag::err_reference_var_requires_init) 2484 << Var->getDeclName() 2485 << SourceRange(Var->getLocation(), Var->getLocation()); 2486 Var->setInvalidDecl(); 2487 return; 2488 } 2489 2490 // C++ [dcl.init]p9: 2491 // 2492 // If no initializer is specified for an object, and the object 2493 // is of (possibly cv-qualified) non-POD class type (or array 2494 // thereof), the object shall be default-initialized; if the 2495 // object is of const-qualified type, the underlying class type 2496 // shall have a user-declared default constructor. 2497 if (getLangOptions().CPlusPlus) { 2498 QualType InitType = Type; 2499 if (const ArrayType *Array = Context.getAsArrayType(Type)) 2500 InitType = Array->getElementType(); 2501 if (Var->getStorageClass() != VarDecl::Extern && 2502 Var->getStorageClass() != VarDecl::PrivateExtern && 2503 InitType->isRecordType()) { 2504 const CXXConstructorDecl *Constructor 2505 = PerformInitializationByConstructor(InitType, 0, 0, 2506 Var->getLocation(), 2507 SourceRange(Var->getLocation(), 2508 Var->getLocation()), 2509 Var->getDeclName(), 2510 IK_Default); 2511 if (!Constructor) 2512 Var->setInvalidDecl(); 2513 } 2514 } 2515 2516#if 0 2517 // FIXME: Temporarily disabled because we are not properly parsing 2518 // linkage specifications on declarations, e.g., 2519 // 2520 // extern "C" const CGPoint CGPointerZero; 2521 // 2522 // C++ [dcl.init]p9: 2523 // 2524 // If no initializer is specified for an object, and the 2525 // object is of (possibly cv-qualified) non-POD class type (or 2526 // array thereof), the object shall be default-initialized; if 2527 // the object is of const-qualified type, the underlying class 2528 // type shall have a user-declared default 2529 // constructor. Otherwise, if no initializer is specified for 2530 // an object, the object and its subobjects, if any, have an 2531 // indeterminate initial value; if the object or any of its 2532 // subobjects are of const-qualified type, the program is 2533 // ill-formed. 2534 // 2535 // This isn't technically an error in C, so we don't diagnose it. 2536 // 2537 // FIXME: Actually perform the POD/user-defined default 2538 // constructor check. 2539 if (getLangOptions().CPlusPlus && 2540 Context.getCanonicalType(Type).isConstQualified() && 2541 Var->getStorageClass() != VarDecl::Extern) 2542 Diag(Var->getLocation(), diag::err_const_var_requires_init) 2543 << Var->getName() 2544 << SourceRange(Var->getLocation(), Var->getLocation()); 2545#endif 2546 } 2547} 2548 2549/// The declarators are chained together backwards, reverse the list. 2550Sema::DeclTy *Sema::FinalizeDeclaratorGroup(Scope *S, DeclTy *group) { 2551 // Often we have single declarators, handle them quickly. 2552 Decl *Group = static_cast<Decl*>(group); 2553 if (Group == 0) 2554 return 0; 2555 2556 Decl *NewGroup = 0; 2557 if (Group->getNextDeclarator() == 0) 2558 NewGroup = Group; 2559 else { // reverse the list. 2560 while (Group) { 2561 Decl *Next = Group->getNextDeclarator(); 2562 Group->setNextDeclarator(NewGroup); 2563 NewGroup = Group; 2564 Group = Next; 2565 } 2566 } 2567 // Perform semantic analysis that depends on having fully processed both 2568 // the declarator and initializer. 2569 for (Decl *ID = NewGroup; ID; ID = ID->getNextDeclarator()) { 2570 VarDecl *IDecl = dyn_cast<VarDecl>(ID); 2571 if (!IDecl) 2572 continue; 2573 QualType T = IDecl->getType(); 2574 2575 if (T->isVariableArrayType()) { 2576 const VariableArrayType *VAT = Context.getAsVariableArrayType(T); 2577 2578 // FIXME: This won't give the correct result for 2579 // int a[10][n]; 2580 SourceRange SizeRange = VAT->getSizeExpr()->getSourceRange(); 2581 if (IDecl->isFileVarDecl()) { 2582 Diag(IDecl->getLocation(), diag::err_vla_decl_in_file_scope) << 2583 SizeRange; 2584 2585 IDecl->setInvalidDecl(); 2586 } else { 2587 // C99 6.7.5.2p2: If an identifier is declared to be an object with 2588 // static storage duration, it shall not have a variable length array. 2589 if (IDecl->getStorageClass() == VarDecl::Static) { 2590 Diag(IDecl->getLocation(), diag::err_vla_decl_has_static_storage) 2591 << SizeRange; 2592 IDecl->setInvalidDecl(); 2593 } else if (IDecl->getStorageClass() == VarDecl::Extern) { 2594 Diag(IDecl->getLocation(), diag::err_vla_decl_has_extern_linkage) 2595 << SizeRange; 2596 IDecl->setInvalidDecl(); 2597 } 2598 } 2599 } else if (T->isVariablyModifiedType()) { 2600 if (IDecl->isFileVarDecl()) { 2601 Diag(IDecl->getLocation(), diag::err_vm_decl_in_file_scope); 2602 IDecl->setInvalidDecl(); 2603 } else { 2604 if (IDecl->getStorageClass() == VarDecl::Extern) { 2605 Diag(IDecl->getLocation(), diag::err_vm_decl_has_extern_linkage); 2606 IDecl->setInvalidDecl(); 2607 } 2608 } 2609 } 2610 2611 // Block scope. C99 6.7p7: If an identifier for an object is declared with 2612 // no linkage (C99 6.2.2p6), the type for the object shall be complete... 2613 if (IDecl->isBlockVarDecl() && 2614 IDecl->getStorageClass() != VarDecl::Extern) { 2615 if (!IDecl->isInvalidDecl() && 2616 DiagnoseIncompleteType(IDecl->getLocation(), T, 2617 diag::err_typecheck_decl_incomplete_type)) 2618 IDecl->setInvalidDecl(); 2619 } 2620 // File scope. C99 6.9.2p2: A declaration of an identifier for and 2621 // object that has file scope without an initializer, and without a 2622 // storage-class specifier or with the storage-class specifier "static", 2623 // constitutes a tentative definition. Note: A tentative definition with 2624 // external linkage is valid (C99 6.2.2p5). 2625 if (isTentativeDefinition(IDecl)) { 2626 if (T->isIncompleteArrayType()) { 2627 // C99 6.9.2 (p2, p5): Implicit initialization causes an incomplete 2628 // array to be completed. Don't issue a diagnostic. 2629 } else if (!IDecl->isInvalidDecl() && 2630 DiagnoseIncompleteType(IDecl->getLocation(), T, 2631 diag::err_typecheck_decl_incomplete_type)) 2632 // C99 6.9.2p3: If the declaration of an identifier for an object is 2633 // a tentative definition and has internal linkage (C99 6.2.2p3), the 2634 // declared type shall not be an incomplete type. 2635 IDecl->setInvalidDecl(); 2636 } 2637 if (IDecl->isFileVarDecl()) 2638 CheckForFileScopedRedefinitions(S, IDecl); 2639 } 2640 return NewGroup; 2641} 2642 2643/// ActOnParamDeclarator - Called from Parser::ParseFunctionDeclarator() 2644/// to introduce parameters into function prototype scope. 2645Sema::DeclTy * 2646Sema::ActOnParamDeclarator(Scope *S, Declarator &D) { 2647 const DeclSpec &DS = D.getDeclSpec(); 2648 2649 // Verify C99 6.7.5.3p2: The only SCS allowed is 'register'. 2650 VarDecl::StorageClass StorageClass = VarDecl::None; 2651 if (DS.getStorageClassSpec() == DeclSpec::SCS_register) { 2652 StorageClass = VarDecl::Register; 2653 } else if (DS.getStorageClassSpec() != DeclSpec::SCS_unspecified) { 2654 Diag(DS.getStorageClassSpecLoc(), 2655 diag::err_invalid_storage_class_in_func_decl); 2656 D.getMutableDeclSpec().ClearStorageClassSpecs(); 2657 } 2658 if (DS.isThreadSpecified()) { 2659 Diag(DS.getThreadSpecLoc(), 2660 diag::err_invalid_storage_class_in_func_decl); 2661 D.getMutableDeclSpec().ClearStorageClassSpecs(); 2662 } 2663 2664 // Check that there are no default arguments inside the type of this 2665 // parameter (C++ only). 2666 if (getLangOptions().CPlusPlus) 2667 CheckExtraCXXDefaultArguments(D); 2668 2669 // In this context, we *do not* check D.getInvalidType(). If the declarator 2670 // type was invalid, GetTypeForDeclarator() still returns a "valid" type, 2671 // though it will not reflect the user specified type. 2672 QualType parmDeclType = GetTypeForDeclarator(D, S); 2673 2674 assert(!parmDeclType.isNull() && "GetTypeForDeclarator() returned null type"); 2675 2676 // TODO: CHECK FOR CONFLICTS, multiple decls with same name in one scope. 2677 // Can this happen for params? We already checked that they don't conflict 2678 // among each other. Here they can only shadow globals, which is ok. 2679 IdentifierInfo *II = D.getIdentifier(); 2680 if (II) { 2681 if (NamedDecl *PrevDecl = LookupName(S, II, LookupOrdinaryName)) { 2682 if (PrevDecl->isTemplateParameter()) { 2683 // Maybe we will complain about the shadowed template parameter. 2684 DiagnoseTemplateParameterShadow(D.getIdentifierLoc(), PrevDecl); 2685 // Just pretend that we didn't see the previous declaration. 2686 PrevDecl = 0; 2687 } else if (S->isDeclScope(PrevDecl)) { 2688 Diag(D.getIdentifierLoc(), diag::err_param_redefinition) << II; 2689 2690 // Recover by removing the name 2691 II = 0; 2692 D.SetIdentifier(0, D.getIdentifierLoc()); 2693 } 2694 } 2695 } 2696 2697 // Perform the default function/array conversion (C99 6.7.5.3p[7,8]). 2698 // Doing the promotion here has a win and a loss. The win is the type for 2699 // both Decl's and DeclRefExpr's will match (a convenient invariant for the 2700 // code generator). The loss is the orginal type isn't preserved. For example: 2701 // 2702 // void func(int parmvardecl[5]) { // convert "int [5]" to "int *" 2703 // int blockvardecl[5]; 2704 // sizeof(parmvardecl); // size == 4 2705 // sizeof(blockvardecl); // size == 20 2706 // } 2707 // 2708 // For expressions, all implicit conversions are captured using the 2709 // ImplicitCastExpr AST node (we have no such mechanism for Decl's). 2710 // 2711 // FIXME: If a source translation tool needs to see the original type, then 2712 // we need to consider storing both types (in ParmVarDecl)... 2713 // 2714 if (parmDeclType->isArrayType()) { 2715 // int x[restrict 4] -> int *restrict 2716 parmDeclType = Context.getArrayDecayedType(parmDeclType); 2717 } else if (parmDeclType->isFunctionType()) 2718 parmDeclType = Context.getPointerType(parmDeclType); 2719 2720 ParmVarDecl *New = ParmVarDecl::Create(Context, CurContext, 2721 D.getIdentifierLoc(), II, 2722 parmDeclType, StorageClass, 2723 0); 2724 2725 if (D.getInvalidType()) 2726 New->setInvalidDecl(); 2727 2728 // Parameter declarators cannot be qualified (C++ [dcl.meaning]p1). 2729 if (D.getCXXScopeSpec().isSet()) { 2730 Diag(D.getIdentifierLoc(), diag::err_qualified_param_declarator) 2731 << D.getCXXScopeSpec().getRange(); 2732 New->setInvalidDecl(); 2733 } 2734 2735 // Add the parameter declaration into this scope. 2736 S->AddDecl(New); 2737 if (II) 2738 IdResolver.AddDecl(New); 2739 2740 ProcessDeclAttributes(New, D); 2741 return New; 2742 2743} 2744 2745void Sema::ActOnFinishKNRParamDeclarations(Scope *S, Declarator &D) { 2746 assert(D.getTypeObject(0).Kind == DeclaratorChunk::Function && 2747 "Not a function declarator!"); 2748 DeclaratorChunk::FunctionTypeInfo &FTI = D.getTypeObject(0).Fun; 2749 2750 // Verify 6.9.1p6: 'every identifier in the identifier list shall be declared' 2751 // for a K&R function. 2752 if (!FTI.hasPrototype) { 2753 for (unsigned i = 0, e = FTI.NumArgs; i != e; ++i) { 2754 if (FTI.ArgInfo[i].Param == 0) { 2755 Diag(FTI.ArgInfo[i].IdentLoc, diag::ext_param_not_declared) 2756 << FTI.ArgInfo[i].Ident; 2757 // Implicitly declare the argument as type 'int' for lack of a better 2758 // type. 2759 DeclSpec DS; 2760 const char* PrevSpec; // unused 2761 DS.SetTypeSpecType(DeclSpec::TST_int, FTI.ArgInfo[i].IdentLoc, 2762 PrevSpec); 2763 Declarator ParamD(DS, Declarator::KNRTypeListContext); 2764 ParamD.SetIdentifier(FTI.ArgInfo[i].Ident, FTI.ArgInfo[i].IdentLoc); 2765 FTI.ArgInfo[i].Param = ActOnParamDeclarator(S, ParamD); 2766 } 2767 } 2768 } 2769} 2770 2771Sema::DeclTy *Sema::ActOnStartOfFunctionDef(Scope *FnBodyScope, Declarator &D) { 2772 assert(getCurFunctionDecl() == 0 && "Function parsing confused"); 2773 assert(D.getTypeObject(0).Kind == DeclaratorChunk::Function && 2774 "Not a function declarator!"); 2775 DeclaratorChunk::FunctionTypeInfo &FTI = D.getTypeObject(0).Fun; 2776 2777 if (FTI.hasPrototype) { 2778 // FIXME: Diagnose arguments without names in C. 2779 } 2780 2781 Scope *ParentScope = FnBodyScope->getParent(); 2782 2783 return ActOnStartOfFunctionDef(FnBodyScope, 2784 ActOnDeclarator(ParentScope, D, 0, 2785 /*IsFunctionDefinition=*/true)); 2786} 2787 2788Sema::DeclTy *Sema::ActOnStartOfFunctionDef(Scope *FnBodyScope, DeclTy *D) { 2789 Decl *decl = static_cast<Decl*>(D); 2790 FunctionDecl *FD = cast<FunctionDecl>(decl); 2791 2792 // See if this is a redefinition. 2793 const FunctionDecl *Definition; 2794 if (FD->getBody(Definition)) { 2795 Diag(FD->getLocation(), diag::err_redefinition) << FD->getDeclName(); 2796 Diag(Definition->getLocation(), diag::note_previous_definition); 2797 } 2798 2799 // Builtin functions cannot be defined. 2800 if (unsigned BuiltinID = FD->getBuiltinID(Context)) { 2801 if (!Context.BuiltinInfo.isPredefinedLibFunction(BuiltinID)) { 2802 Diag(FD->getLocation(), diag::err_builtin_definition) << FD; 2803 FD->setInvalidDecl(); 2804 } 2805 } 2806 2807 PushDeclContext(FnBodyScope, FD); 2808 2809 // Check the validity of our function parameters 2810 CheckParmsForFunctionDef(FD); 2811 2812 // Introduce our parameters into the function scope 2813 for (unsigned p = 0, NumParams = FD->getNumParams(); p < NumParams; ++p) { 2814 ParmVarDecl *Param = FD->getParamDecl(p); 2815 Param->setOwningFunction(FD); 2816 2817 // If this has an identifier, add it to the scope stack. 2818 if (Param->getIdentifier()) 2819 PushOnScopeChains(Param, FnBodyScope); 2820 } 2821 2822 // Checking attributes of current function definition 2823 // dllimport attribute. 2824 if (FD->getAttr<DLLImportAttr>() && (!FD->getAttr<DLLExportAttr>())) { 2825 // dllimport attribute cannot be applied to definition. 2826 if (!(FD->getAttr<DLLImportAttr>())->isInherited()) { 2827 Diag(FD->getLocation(), 2828 diag::err_attribute_can_be_applied_only_to_symbol_declaration) 2829 << "dllimport"; 2830 FD->setInvalidDecl(); 2831 return FD; 2832 } else { 2833 // If a symbol previously declared dllimport is later defined, the 2834 // attribute is ignored in subsequent references, and a warning is 2835 // emitted. 2836 Diag(FD->getLocation(), 2837 diag::warn_redeclaration_without_attribute_prev_attribute_ignored) 2838 << FD->getNameAsCString() << "dllimport"; 2839 } 2840 } 2841 return FD; 2842} 2843 2844Sema::DeclTy *Sema::ActOnFinishFunctionBody(DeclTy *D, StmtArg BodyArg) { 2845 Decl *dcl = static_cast<Decl *>(D); 2846 Stmt *Body = static_cast<Stmt*>(BodyArg.release()); 2847 if (FunctionDecl *FD = dyn_cast_or_null<FunctionDecl>(dcl)) { 2848 FD->setBody(Body); 2849 assert(FD == getCurFunctionDecl() && "Function parsing confused"); 2850 } else if (ObjCMethodDecl *MD = dyn_cast_or_null<ObjCMethodDecl>(dcl)) { 2851 assert(MD == getCurMethodDecl() && "Method parsing confused"); 2852 MD->setBody((Stmt*)Body); 2853 } else { 2854 Body->Destroy(Context); 2855 return 0; 2856 } 2857 PopDeclContext(); 2858 // Verify and clean out per-function state. 2859 2860 // Check goto/label use. 2861 for (llvm::DenseMap<IdentifierInfo*, LabelStmt*>::iterator 2862 I = LabelMap.begin(), E = LabelMap.end(); I != E; ++I) { 2863 // Verify that we have no forward references left. If so, there was a goto 2864 // or address of a label taken, but no definition of it. Label fwd 2865 // definitions are indicated with a null substmt. 2866 if (I->second->getSubStmt() == 0) { 2867 LabelStmt *L = I->second; 2868 // Emit error. 2869 Diag(L->getIdentLoc(), diag::err_undeclared_label_use) << L->getName(); 2870 2871 // At this point, we have gotos that use the bogus label. Stitch it into 2872 // the function body so that they aren't leaked and that the AST is well 2873 // formed. 2874 if (Body) { 2875#if 0 2876 // FIXME: Why do this? Having a 'push_back' in CompoundStmt is ugly, 2877 // and the AST is malformed anyway. We should just blow away 'L'. 2878 L->setSubStmt(new (Context) NullStmt(L->getIdentLoc())); 2879 cast<CompoundStmt>(Body)->push_back(L); 2880#else 2881 L->Destroy(Context); 2882#endif 2883 } else { 2884 // The whole function wasn't parsed correctly, just delete this. 2885 L->Destroy(Context); 2886 } 2887 } 2888 } 2889 LabelMap.clear(); 2890 2891 return D; 2892} 2893 2894/// ImplicitlyDefineFunction - An undeclared identifier was used in a function 2895/// call, forming a call to an implicitly defined function (per C99 6.5.1p2). 2896NamedDecl *Sema::ImplicitlyDefineFunction(SourceLocation Loc, 2897 IdentifierInfo &II, Scope *S) { 2898 // Extension in C99. Legal in C90, but warn about it. 2899 if (getLangOptions().C99) 2900 Diag(Loc, diag::ext_implicit_function_decl) << &II; 2901 else 2902 Diag(Loc, diag::warn_implicit_function_decl) << &II; 2903 2904 // FIXME: handle stuff like: 2905 // void foo() { extern float X(); } 2906 // void bar() { X(); } <-- implicit decl for X in another scope. 2907 2908 // Set a Declarator for the implicit definition: int foo(); 2909 const char *Dummy; 2910 DeclSpec DS; 2911 bool Error = DS.SetTypeSpecType(DeclSpec::TST_int, Loc, Dummy); 2912 Error = Error; // Silence warning. 2913 assert(!Error && "Error setting up implicit decl!"); 2914 Declarator D(DS, Declarator::BlockContext); 2915 D.AddTypeInfo(DeclaratorChunk::getFunction(false, false, 0, 0, 0, Loc, D), 2916 SourceLocation()); 2917 D.SetIdentifier(&II, Loc); 2918 2919 // Insert this function into translation-unit scope. 2920 2921 DeclContext *PrevDC = CurContext; 2922 CurContext = Context.getTranslationUnitDecl(); 2923 2924 FunctionDecl *FD = 2925 dyn_cast<FunctionDecl>(static_cast<Decl*>(ActOnDeclarator(TUScope, D, 0))); 2926 FD->setImplicit(); 2927 2928 CurContext = PrevDC; 2929 2930 AddKnownFunctionAttributes(FD); 2931 2932 return FD; 2933} 2934 2935/// \brief Adds any function attributes that we know a priori based on 2936/// the declaration of this function. 2937/// 2938/// These attributes can apply both to implicitly-declared builtins 2939/// (like __builtin___printf_chk) or to library-declared functions 2940/// like NSLog or printf. 2941void Sema::AddKnownFunctionAttributes(FunctionDecl *FD) { 2942 if (FD->isInvalidDecl()) 2943 return; 2944 2945 // If this is a built-in function, map its builtin attributes to 2946 // actual attributes. 2947 if (unsigned BuiltinID = FD->getBuiltinID(Context)) { 2948 // Handle printf-formatting attributes. 2949 unsigned FormatIdx; 2950 bool HasVAListArg; 2951 if (Context.BuiltinInfo.isPrintfLike(BuiltinID, FormatIdx, HasVAListArg)) { 2952 if (!FD->getAttr<FormatAttr>()) 2953 FD->addAttr(new FormatAttr("printf", FormatIdx + 1, FormatIdx + 2)); 2954 } 2955 2956 // Mark const if we don't care about errno and that is the only 2957 // thing preventing the function from being const. This allows 2958 // IRgen to use LLVM intrinsics for such functions. 2959 if (!getLangOptions().MathErrno && 2960 Context.BuiltinInfo.isConstWithoutErrno(BuiltinID)) { 2961 if (!FD->getAttr<ConstAttr>()) 2962 FD->addAttr(new ConstAttr()); 2963 } 2964 } 2965 2966 IdentifierInfo *Name = FD->getIdentifier(); 2967 if (!Name) 2968 return; 2969 if ((!getLangOptions().CPlusPlus && 2970 FD->getDeclContext()->isTranslationUnit()) || 2971 (isa<LinkageSpecDecl>(FD->getDeclContext()) && 2972 cast<LinkageSpecDecl>(FD->getDeclContext())->getLanguage() == 2973 LinkageSpecDecl::lang_c)) { 2974 // Okay: this could be a libc/libm/Objective-C function we know 2975 // about. 2976 } else 2977 return; 2978 2979 unsigned KnownID; 2980 for (KnownID = 0; KnownID != id_num_known_functions; ++KnownID) 2981 if (KnownFunctionIDs[KnownID] == Name) 2982 break; 2983 2984 switch (KnownID) { 2985 case id_NSLog: 2986 case id_NSLogv: 2987 if (const FormatAttr *Format = FD->getAttr<FormatAttr>()) { 2988 // FIXME: We known better than our headers. 2989 const_cast<FormatAttr *>(Format)->setType("printf"); 2990 } else 2991 FD->addAttr(new FormatAttr("printf", 1, 2)); 2992 break; 2993 2994 case id_asprintf: 2995 case id_vasprintf: 2996 if (!FD->getAttr<FormatAttr>()) 2997 FD->addAttr(new FormatAttr("printf", 2, 3)); 2998 break; 2999 3000 default: 3001 // Unknown function or known function without any attributes to 3002 // add. Do nothing. 3003 break; 3004 } 3005} 3006 3007TypedefDecl *Sema::ParseTypedefDecl(Scope *S, Declarator &D, QualType T, 3008 Decl *LastDeclarator) { 3009 assert(D.getIdentifier() && "Wrong callback for declspec without declarator"); 3010 assert(!T.isNull() && "GetTypeForDeclarator() returned null type"); 3011 3012 // Scope manipulation handled by caller. 3013 TypedefDecl *NewTD = TypedefDecl::Create(Context, CurContext, 3014 D.getIdentifierLoc(), 3015 D.getIdentifier(), 3016 T); 3017 NewTD->setNextDeclarator(LastDeclarator); 3018 if (D.getInvalidType()) 3019 NewTD->setInvalidDecl(); 3020 return NewTD; 3021} 3022 3023/// ActOnTag - This is invoked when we see 'struct foo' or 'struct {'. In the 3024/// former case, Name will be non-null. In the later case, Name will be null. 3025/// TagSpec indicates what kind of tag this is. TK indicates whether this is a 3026/// reference/declaration/definition of a tag. 3027Sema::DeclTy *Sema::ActOnTag(Scope *S, unsigned TagSpec, TagKind TK, 3028 SourceLocation KWLoc, const CXXScopeSpec &SS, 3029 IdentifierInfo *Name, SourceLocation NameLoc, 3030 AttributeList *Attr) { 3031 // If this is not a definition, it must have a name. 3032 assert((Name != 0 || TK == TK_Definition) && 3033 "Nameless record must be a definition!"); 3034 3035 TagDecl::TagKind Kind; 3036 switch (TagSpec) { 3037 default: assert(0 && "Unknown tag type!"); 3038 case DeclSpec::TST_struct: Kind = TagDecl::TK_struct; break; 3039 case DeclSpec::TST_union: Kind = TagDecl::TK_union; break; 3040 case DeclSpec::TST_class: Kind = TagDecl::TK_class; break; 3041 case DeclSpec::TST_enum: Kind = TagDecl::TK_enum; break; 3042 } 3043 3044 DeclContext *SearchDC = CurContext; 3045 DeclContext *DC = CurContext; 3046 NamedDecl *PrevDecl = 0; 3047 3048 bool Invalid = false; 3049 3050 if (Name && SS.isNotEmpty()) { 3051 // We have a nested-name tag ('struct foo::bar'). 3052 3053 // Check for invalid 'foo::'. 3054 if (SS.isInvalid()) { 3055 Name = 0; 3056 goto CreateNewDecl; 3057 } 3058 3059 DC = static_cast<DeclContext*>(SS.getScopeRep()); 3060 SearchDC = DC; 3061 // Look-up name inside 'foo::'. 3062 PrevDecl = dyn_cast_or_null<TagDecl>( 3063 LookupQualifiedName(DC, Name, LookupTagName, true).getAsDecl()); 3064 3065 // A tag 'foo::bar' must already exist. 3066 if (PrevDecl == 0) { 3067 Diag(NameLoc, diag::err_not_tag_in_scope) << Name << SS.getRange(); 3068 Name = 0; 3069 goto CreateNewDecl; 3070 } 3071 } else if (Name) { 3072 // If this is a named struct, check to see if there was a previous forward 3073 // declaration or definition. 3074 // FIXME: We're looking into outer scopes here, even when we 3075 // shouldn't be. Doing so can result in ambiguities that we 3076 // shouldn't be diagnosing. 3077 LookupResult R = LookupName(S, Name, LookupTagName, 3078 /*RedeclarationOnly=*/(TK != TK_Reference)); 3079 if (R.isAmbiguous()) { 3080 DiagnoseAmbiguousLookup(R, Name, NameLoc); 3081 // FIXME: This is not best way to recover from case like: 3082 // 3083 // struct S s; 3084 // 3085 // causes needless err_ovl_no_viable_function_in_init latter. 3086 Name = 0; 3087 PrevDecl = 0; 3088 Invalid = true; 3089 } 3090 else 3091 PrevDecl = R; 3092 3093 if (!getLangOptions().CPlusPlus && TK != TK_Reference) { 3094 // FIXME: This makes sure that we ignore the contexts associated 3095 // with C structs, unions, and enums when looking for a matching 3096 // tag declaration or definition. See the similar lookup tweak 3097 // in Sema::LookupName; is there a better way to deal with this? 3098 while (isa<RecordDecl>(SearchDC) || isa<EnumDecl>(SearchDC)) 3099 SearchDC = SearchDC->getParent(); 3100 } 3101 } 3102 3103 if (PrevDecl && PrevDecl->isTemplateParameter()) { 3104 // Maybe we will complain about the shadowed template parameter. 3105 DiagnoseTemplateParameterShadow(NameLoc, PrevDecl); 3106 // Just pretend that we didn't see the previous declaration. 3107 PrevDecl = 0; 3108 } 3109 3110 if (PrevDecl) { 3111 // If the previous declaration was deprecated, emit a warning. 3112 DiagnoseUseOfDeprecatedDecl(PrevDecl, NameLoc); 3113 3114 if (TagDecl *PrevTagDecl = dyn_cast<TagDecl>(PrevDecl)) { 3115 // If this is a use of a previous tag, or if the tag is already declared 3116 // in the same scope (so that the definition/declaration completes or 3117 // rementions the tag), reuse the decl. 3118 if (TK == TK_Reference || isDeclInScope(PrevDecl, SearchDC, S)) { 3119 // Make sure that this wasn't declared as an enum and now used as a 3120 // struct or something similar. 3121 if (PrevTagDecl->getTagKind() != Kind) { 3122 Diag(KWLoc, diag::err_use_with_wrong_tag) << Name; 3123 Diag(PrevDecl->getLocation(), diag::note_previous_use); 3124 // Recover by making this an anonymous redefinition. 3125 Name = 0; 3126 PrevDecl = 0; 3127 Invalid = true; 3128 } else { 3129 // If this is a use, just return the declaration we found. 3130 3131 // FIXME: In the future, return a variant or some other clue 3132 // for the consumer of this Decl to know it doesn't own it. 3133 // For our current ASTs this shouldn't be a problem, but will 3134 // need to be changed with DeclGroups. 3135 if (TK == TK_Reference) 3136 return PrevDecl; 3137 3138 // Diagnose attempts to redefine a tag. 3139 if (TK == TK_Definition) { 3140 if (TagDecl *Def = PrevTagDecl->getDefinition(Context)) { 3141 Diag(NameLoc, diag::err_redefinition) << Name; 3142 Diag(Def->getLocation(), diag::note_previous_definition); 3143 // If this is a redefinition, recover by making this 3144 // struct be anonymous, which will make any later 3145 // references get the previous definition. 3146 Name = 0; 3147 PrevDecl = 0; 3148 Invalid = true; 3149 } else { 3150 // If the type is currently being defined, complain 3151 // about a nested redefinition. 3152 TagType *Tag = cast<TagType>(Context.getTagDeclType(PrevTagDecl)); 3153 if (Tag->isBeingDefined()) { 3154 Diag(NameLoc, diag::err_nested_redefinition) << Name; 3155 Diag(PrevTagDecl->getLocation(), 3156 diag::note_previous_definition); 3157 Name = 0; 3158 PrevDecl = 0; 3159 Invalid = true; 3160 } 3161 } 3162 3163 // Okay, this is definition of a previously declared or referenced 3164 // tag PrevDecl. We're going to create a new Decl for it. 3165 } 3166 } 3167 // If we get here we have (another) forward declaration or we 3168 // have a definition. Just create a new decl. 3169 } else { 3170 // If we get here, this is a definition of a new tag type in a nested 3171 // scope, e.g. "struct foo; void bar() { struct foo; }", just create a 3172 // new decl/type. We set PrevDecl to NULL so that the entities 3173 // have distinct types. 3174 PrevDecl = 0; 3175 } 3176 // If we get here, we're going to create a new Decl. If PrevDecl 3177 // is non-NULL, it's a definition of the tag declared by 3178 // PrevDecl. If it's NULL, we have a new definition. 3179 } else { 3180 // PrevDecl is a namespace, template, or anything else 3181 // that lives in the IDNS_Tag identifier namespace. 3182 if (isDeclInScope(PrevDecl, SearchDC, S)) { 3183 // The tag name clashes with a namespace name, issue an error and 3184 // recover by making this tag be anonymous. 3185 Diag(NameLoc, diag::err_redefinition_different_kind) << Name; 3186 Diag(PrevDecl->getLocation(), diag::note_previous_definition); 3187 Name = 0; 3188 PrevDecl = 0; 3189 Invalid = true; 3190 } else { 3191 // The existing declaration isn't relevant to us; we're in a 3192 // new scope, so clear out the previous declaration. 3193 PrevDecl = 0; 3194 } 3195 } 3196 } else if (TK == TK_Reference && SS.isEmpty() && Name && 3197 (Kind != TagDecl::TK_enum)) { 3198 // C++ [basic.scope.pdecl]p5: 3199 // -- for an elaborated-type-specifier of the form 3200 // 3201 // class-key identifier 3202 // 3203 // if the elaborated-type-specifier is used in the 3204 // decl-specifier-seq or parameter-declaration-clause of a 3205 // function defined in namespace scope, the identifier is 3206 // declared as a class-name in the namespace that contains 3207 // the declaration; otherwise, except as a friend 3208 // declaration, the identifier is declared in the smallest 3209 // non-class, non-function-prototype scope that contains the 3210 // declaration. 3211 // 3212 // C99 6.7.2.3p8 has a similar (but not identical!) provision for 3213 // C structs and unions. 3214 3215 // Find the context where we'll be declaring the tag. 3216 // FIXME: We would like to maintain the current DeclContext as the 3217 // lexical context, 3218 while (SearchDC->isRecord()) 3219 SearchDC = SearchDC->getParent(); 3220 3221 // Find the scope where we'll be declaring the tag. 3222 while (S->isClassScope() || 3223 (getLangOptions().CPlusPlus && S->isFunctionPrototypeScope()) || 3224 ((S->getFlags() & Scope::DeclScope) == 0) || 3225 (S->getEntity() && 3226 ((DeclContext *)S->getEntity())->isTransparentContext())) 3227 S = S->getParent(); 3228 } 3229 3230CreateNewDecl: 3231 3232 // If there is an identifier, use the location of the identifier as the 3233 // location of the decl, otherwise use the location of the struct/union 3234 // keyword. 3235 SourceLocation Loc = NameLoc.isValid() ? NameLoc : KWLoc; 3236 3237 // Otherwise, create a new declaration. If there is a previous 3238 // declaration of the same entity, the two will be linked via 3239 // PrevDecl. 3240 TagDecl *New; 3241 3242 if (Kind == TagDecl::TK_enum) { 3243 // FIXME: Tag decls should be chained to any simultaneous vardecls, e.g.: 3244 // enum X { A, B, C } D; D should chain to X. 3245 New = EnumDecl::Create(Context, SearchDC, Loc, Name, 3246 cast_or_null<EnumDecl>(PrevDecl)); 3247 // If this is an undefined enum, warn. 3248 if (TK != TK_Definition) Diag(Loc, diag::ext_forward_ref_enum); 3249 } else { 3250 // struct/union/class 3251 3252 // FIXME: Tag decls should be chained to any simultaneous vardecls, e.g.: 3253 // struct X { int A; } D; D should chain to X. 3254 if (getLangOptions().CPlusPlus) 3255 // FIXME: Look for a way to use RecordDecl for simple structs. 3256 New = CXXRecordDecl::Create(Context, Kind, SearchDC, Loc, Name, 3257 cast_or_null<CXXRecordDecl>(PrevDecl)); 3258 else 3259 New = RecordDecl::Create(Context, Kind, SearchDC, Loc, Name, 3260 cast_or_null<RecordDecl>(PrevDecl)); 3261 } 3262 3263 if (Kind != TagDecl::TK_enum) { 3264 // Handle #pragma pack: if the #pragma pack stack has non-default 3265 // alignment, make up a packed attribute for this decl. These 3266 // attributes are checked when the ASTContext lays out the 3267 // structure. 3268 // 3269 // It is important for implementing the correct semantics that this 3270 // happen here (in act on tag decl). The #pragma pack stack is 3271 // maintained as a result of parser callbacks which can occur at 3272 // many points during the parsing of a struct declaration (because 3273 // the #pragma tokens are effectively skipped over during the 3274 // parsing of the struct). 3275 if (unsigned Alignment = getPragmaPackAlignment()) 3276 New->addAttr(new PackedAttr(Alignment * 8)); 3277 } 3278 3279 if (getLangOptions().CPlusPlus && SS.isEmpty() && Name && !Invalid) { 3280 // C++ [dcl.typedef]p3: 3281 // [...] Similarly, in a given scope, a class or enumeration 3282 // shall not be declared with the same name as a typedef-name 3283 // that is declared in that scope and refers to a type other 3284 // than the class or enumeration itself. 3285 LookupResult Lookup = LookupName(S, Name, LookupOrdinaryName, true); 3286 TypedefDecl *PrevTypedef = 0; 3287 if (Lookup.getKind() == LookupResult::Found) 3288 PrevTypedef = dyn_cast<TypedefDecl>(Lookup.getAsDecl()); 3289 3290 if (PrevTypedef && isDeclInScope(PrevTypedef, SearchDC, S) && 3291 Context.getCanonicalType(Context.getTypeDeclType(PrevTypedef)) != 3292 Context.getCanonicalType(Context.getTypeDeclType(New))) { 3293 Diag(Loc, diag::err_tag_definition_of_typedef) 3294 << Context.getTypeDeclType(New) 3295 << PrevTypedef->getUnderlyingType(); 3296 Diag(PrevTypedef->getLocation(), diag::note_previous_definition); 3297 Invalid = true; 3298 } 3299 } 3300 3301 if (Invalid) 3302 New->setInvalidDecl(); 3303 3304 if (Attr) 3305 ProcessDeclAttributeList(New, Attr); 3306 3307 // If we're declaring or defining a tag in function prototype scope 3308 // in C, note that this type can only be used within the function. 3309 if (Name && S->isFunctionPrototypeScope() && !getLangOptions().CPlusPlus) 3310 Diag(Loc, diag::warn_decl_in_param_list) << Context.getTagDeclType(New); 3311 3312 // Set the lexical context. If the tag has a C++ scope specifier, the 3313 // lexical context will be different from the semantic context. 3314 New->setLexicalDeclContext(CurContext); 3315 3316 if (TK == TK_Definition) 3317 New->startDefinition(); 3318 3319 // If this has an identifier, add it to the scope stack. 3320 if (Name) { 3321 S = getNonFieldDeclScope(S); 3322 PushOnScopeChains(New, S); 3323 } else { 3324 CurContext->addDecl(New); 3325 } 3326 3327 return New; 3328} 3329 3330void Sema::ActOnTagStartDefinition(Scope *S, DeclTy *TagD) { 3331 AdjustDeclIfTemplate(TagD); 3332 TagDecl *Tag = cast<TagDecl>((Decl *)TagD); 3333 3334 // Enter the tag context. 3335 PushDeclContext(S, Tag); 3336 3337 if (CXXRecordDecl *Record = dyn_cast<CXXRecordDecl>(Tag)) { 3338 FieldCollector->StartClass(); 3339 3340 if (Record->getIdentifier()) { 3341 // C++ [class]p2: 3342 // [...] The class-name is also inserted into the scope of the 3343 // class itself; this is known as the injected-class-name. For 3344 // purposes of access checking, the injected-class-name is treated 3345 // as if it were a public member name. 3346 RecordDecl *InjectedClassName 3347 = CXXRecordDecl::Create(Context, Record->getTagKind(), 3348 CurContext, Record->getLocation(), 3349 Record->getIdentifier(), Record); 3350 InjectedClassName->setImplicit(); 3351 PushOnScopeChains(InjectedClassName, S); 3352 } 3353 } 3354} 3355 3356void Sema::ActOnTagFinishDefinition(Scope *S, DeclTy *TagD) { 3357 AdjustDeclIfTemplate(TagD); 3358 TagDecl *Tag = cast<TagDecl>((Decl *)TagD); 3359 3360 if (isa<CXXRecordDecl>(Tag)) 3361 FieldCollector->FinishClass(); 3362 3363 // Exit this scope of this tag's definition. 3364 PopDeclContext(); 3365 3366 // Notify the consumer that we've defined a tag. 3367 Consumer.HandleTagDeclDefinition(Tag); 3368} 3369 3370/// TryToFixInvalidVariablyModifiedType - Helper method to turn variable array 3371/// types into constant array types in certain situations which would otherwise 3372/// be errors (for GCC compatibility). 3373static QualType TryToFixInvalidVariablyModifiedType(QualType T, 3374 ASTContext &Context) { 3375 // This method tries to turn a variable array into a constant 3376 // array even when the size isn't an ICE. This is necessary 3377 // for compatibility with code that depends on gcc's buggy 3378 // constant expression folding, like struct {char x[(int)(char*)2];} 3379 const VariableArrayType* VLATy = dyn_cast<VariableArrayType>(T); 3380 if (!VLATy) return QualType(); 3381 3382 Expr::EvalResult EvalResult; 3383 if (!VLATy->getSizeExpr() || 3384 !VLATy->getSizeExpr()->Evaluate(EvalResult, Context)) 3385 return QualType(); 3386 3387 assert(EvalResult.Val.isInt() && "Size expressions must be integers!"); 3388 llvm::APSInt &Res = EvalResult.Val.getInt(); 3389 if (Res >= llvm::APSInt(Res.getBitWidth(), Res.isUnsigned())) 3390 return Context.getConstantArrayType(VLATy->getElementType(), 3391 Res, ArrayType::Normal, 0); 3392 return QualType(); 3393} 3394 3395bool Sema::VerifyBitField(SourceLocation FieldLoc, IdentifierInfo *FieldName, 3396 QualType FieldTy, const Expr *BitWidth) { 3397 // FIXME: 6.7.2.1p4 - verify the field type. 3398 3399 llvm::APSInt Value; 3400 if (VerifyIntegerConstantExpression(BitWidth, &Value)) 3401 return true; 3402 3403 // Zero-width bitfield is ok for anonymous field. 3404 if (Value == 0 && FieldName) 3405 return Diag(FieldLoc, diag::err_bitfield_has_zero_width) << FieldName; 3406 3407 if (Value.isNegative()) 3408 return Diag(FieldLoc, diag::err_bitfield_has_negative_width) << FieldName; 3409 3410 uint64_t TypeSize = Context.getTypeSize(FieldTy); 3411 // FIXME: We won't need the 0 size once we check that the field type is valid. 3412 if (TypeSize && Value.getZExtValue() > TypeSize) 3413 return Diag(FieldLoc, diag::err_bitfield_width_exceeds_type_size) 3414 << FieldName << (unsigned)TypeSize; 3415 3416 return false; 3417} 3418 3419/// ActOnField - Each field of a struct/union/class is passed into this in order 3420/// to create a FieldDecl object for it. 3421Sema::DeclTy *Sema::ActOnField(Scope *S, DeclTy *TagD, 3422 SourceLocation DeclStart, 3423 Declarator &D, ExprTy *BitfieldWidth) { 3424 IdentifierInfo *II = D.getIdentifier(); 3425 Expr *BitWidth = (Expr*)BitfieldWidth; 3426 SourceLocation Loc = DeclStart; 3427 RecordDecl *Record = (RecordDecl *)TagD; 3428 if (II) Loc = D.getIdentifierLoc(); 3429 3430 // FIXME: Unnamed fields can be handled in various different ways, for 3431 // example, unnamed unions inject all members into the struct namespace! 3432 3433 QualType T = GetTypeForDeclarator(D, S); 3434 assert(!T.isNull() && "GetTypeForDeclarator() returned null type"); 3435 bool InvalidDecl = false; 3436 3437 // C99 6.7.2.1p8: A member of a structure or union may have any type other 3438 // than a variably modified type. 3439 if (T->isVariablyModifiedType()) { 3440 QualType FixedTy = TryToFixInvalidVariablyModifiedType(T, Context); 3441 if (!FixedTy.isNull()) { 3442 Diag(Loc, diag::warn_illegal_constant_array_size); 3443 T = FixedTy; 3444 } else { 3445 Diag(Loc, diag::err_typecheck_field_variable_size); 3446 T = Context.IntTy; 3447 InvalidDecl = true; 3448 } 3449 } 3450 3451 if (BitWidth) { 3452 if (VerifyBitField(Loc, II, T, BitWidth)) 3453 InvalidDecl = true; 3454 } else { 3455 // Not a bitfield. 3456 3457 // validate II. 3458 3459 } 3460 3461 // FIXME: Chain fielddecls together. 3462 FieldDecl *NewFD; 3463 3464 NewFD = FieldDecl::Create(Context, Record, 3465 Loc, II, T, BitWidth, 3466 D.getDeclSpec().getStorageClassSpec() == 3467 DeclSpec::SCS_mutable); 3468 3469 if (II) { 3470 NamedDecl *PrevDecl = LookupName(S, II, LookupMemberName, true); 3471 if (PrevDecl && isDeclInScope(PrevDecl, CurContext, S) 3472 && !isa<TagDecl>(PrevDecl)) { 3473 Diag(Loc, diag::err_duplicate_member) << II; 3474 Diag(PrevDecl->getLocation(), diag::note_previous_declaration); 3475 NewFD->setInvalidDecl(); 3476 Record->setInvalidDecl(); 3477 } 3478 } 3479 3480 if (getLangOptions().CPlusPlus) { 3481 CheckExtraCXXDefaultArguments(D); 3482 if (!T->isPODType()) 3483 cast<CXXRecordDecl>(Record)->setPOD(false); 3484 } 3485 3486 ProcessDeclAttributes(NewFD, D); 3487 3488 if (D.getInvalidType() || InvalidDecl) 3489 NewFD->setInvalidDecl(); 3490 3491 if (II) { 3492 PushOnScopeChains(NewFD, S); 3493 } else 3494 Record->addDecl(NewFD); 3495 3496 return NewFD; 3497} 3498 3499/// TranslateIvarVisibility - Translate visibility from a token ID to an 3500/// AST enum value. 3501static ObjCIvarDecl::AccessControl 3502TranslateIvarVisibility(tok::ObjCKeywordKind ivarVisibility) { 3503 switch (ivarVisibility) { 3504 default: assert(0 && "Unknown visitibility kind"); 3505 case tok::objc_private: return ObjCIvarDecl::Private; 3506 case tok::objc_public: return ObjCIvarDecl::Public; 3507 case tok::objc_protected: return ObjCIvarDecl::Protected; 3508 case tok::objc_package: return ObjCIvarDecl::Package; 3509 } 3510} 3511 3512/// ActOnIvar - Each ivar field of an objective-c class is passed into this 3513/// in order to create an IvarDecl object for it. 3514Sema::DeclTy *Sema::ActOnIvar(Scope *S, 3515 SourceLocation DeclStart, 3516 Declarator &D, ExprTy *BitfieldWidth, 3517 tok::ObjCKeywordKind Visibility) { 3518 3519 IdentifierInfo *II = D.getIdentifier(); 3520 Expr *BitWidth = (Expr*)BitfieldWidth; 3521 SourceLocation Loc = DeclStart; 3522 if (II) Loc = D.getIdentifierLoc(); 3523 3524 // FIXME: Unnamed fields can be handled in various different ways, for 3525 // example, unnamed unions inject all members into the struct namespace! 3526 3527 QualType T = GetTypeForDeclarator(D, S); 3528 assert(!T.isNull() && "GetTypeForDeclarator() returned null type"); 3529 bool InvalidDecl = false; 3530 3531 if (BitWidth) { 3532 // TODO: Validate. 3533 //printf("WARNING: BITFIELDS IGNORED!\n"); 3534 3535 // 6.7.2.1p3 3536 // 6.7.2.1p4 3537 3538 } else { 3539 // Not a bitfield. 3540 3541 // validate II. 3542 3543 } 3544 3545 // C99 6.7.2.1p8: A member of a structure or union may have any type other 3546 // than a variably modified type. 3547 if (T->isVariablyModifiedType()) { 3548 Diag(Loc, diag::err_typecheck_ivar_variable_size); 3549 InvalidDecl = true; 3550 } 3551 3552 // Get the visibility (access control) for this ivar. 3553 ObjCIvarDecl::AccessControl ac = 3554 Visibility != tok::objc_not_keyword ? TranslateIvarVisibility(Visibility) 3555 : ObjCIvarDecl::None; 3556 3557 // Construct the decl. 3558 ObjCIvarDecl *NewID = ObjCIvarDecl::Create(Context, CurContext, Loc, II, T,ac, 3559 (Expr *)BitfieldWidth); 3560 3561 if (II) { 3562 NamedDecl *PrevDecl = LookupName(S, II, LookupMemberName, true); 3563 if (PrevDecl && isDeclInScope(PrevDecl, CurContext, S) 3564 && !isa<TagDecl>(PrevDecl)) { 3565 Diag(Loc, diag::err_duplicate_member) << II; 3566 Diag(PrevDecl->getLocation(), diag::note_previous_declaration); 3567 NewID->setInvalidDecl(); 3568 } 3569 } 3570 3571 // Process attributes attached to the ivar. 3572 ProcessDeclAttributes(NewID, D); 3573 3574 if (D.getInvalidType() || InvalidDecl) 3575 NewID->setInvalidDecl(); 3576 3577 if (II) { 3578 // FIXME: When interfaces are DeclContexts, we'll need to add 3579 // these to the interface. 3580 S->AddDecl(NewID); 3581 IdResolver.AddDecl(NewID); 3582 } 3583 3584 return NewID; 3585} 3586 3587void Sema::ActOnFields(Scope* S, 3588 SourceLocation RecLoc, DeclTy *RecDecl, 3589 DeclTy **Fields, unsigned NumFields, 3590 SourceLocation LBrac, SourceLocation RBrac, 3591 AttributeList *Attr) { 3592 Decl *EnclosingDecl = static_cast<Decl*>(RecDecl); 3593 assert(EnclosingDecl && "missing record or interface decl"); 3594 RecordDecl *Record = dyn_cast<RecordDecl>(EnclosingDecl); 3595 3596 // Verify that all the fields are okay. 3597 unsigned NumNamedMembers = 0; 3598 llvm::SmallVector<FieldDecl*, 32> RecFields; 3599 3600 for (unsigned i = 0; i != NumFields; ++i) { 3601 FieldDecl *FD = cast_or_null<FieldDecl>(static_cast<Decl*>(Fields[i])); 3602 assert(FD && "missing field decl"); 3603 3604 // Get the type for the field. 3605 Type *FDTy = FD->getType().getTypePtr(); 3606 3607 if (!FD->isAnonymousStructOrUnion()) { 3608 // Remember all fields written by the user. 3609 RecFields.push_back(FD); 3610 } 3611 3612 // C99 6.7.2.1p2 - A field may not be a function type. 3613 if (FDTy->isFunctionType()) { 3614 Diag(FD->getLocation(), diag::err_field_declared_as_function) 3615 << FD->getDeclName(); 3616 FD->setInvalidDecl(); 3617 EnclosingDecl->setInvalidDecl(); 3618 continue; 3619 } 3620 // C99 6.7.2.1p2 - A field may not be an incomplete type except... 3621 if (FDTy->isIncompleteType()) { 3622 if (!Record) { // Incomplete ivar type is always an error. 3623 DiagnoseIncompleteType(FD->getLocation(), FD->getType(), 3624 diag::err_field_incomplete); 3625 FD->setInvalidDecl(); 3626 EnclosingDecl->setInvalidDecl(); 3627 continue; 3628 } 3629 if (i != NumFields-1 || // ... that the last member ... 3630 !Record->isStruct() || // ... of a structure ... 3631 !FDTy->isArrayType()) { //... may have incomplete array type. 3632 DiagnoseIncompleteType(FD->getLocation(), FD->getType(), 3633 diag::err_field_incomplete); 3634 FD->setInvalidDecl(); 3635 EnclosingDecl->setInvalidDecl(); 3636 continue; 3637 } 3638 if (NumNamedMembers < 1) { //... must have more than named member ... 3639 Diag(FD->getLocation(), diag::err_flexible_array_empty_struct) 3640 << FD->getDeclName(); 3641 FD->setInvalidDecl(); 3642 EnclosingDecl->setInvalidDecl(); 3643 continue; 3644 } 3645 // Okay, we have a legal flexible array member at the end of the struct. 3646 if (Record) 3647 Record->setHasFlexibleArrayMember(true); 3648 } 3649 /// C99 6.7.2.1p2 - a struct ending in a flexible array member cannot be the 3650 /// field of another structure or the element of an array. 3651 if (const RecordType *FDTTy = FDTy->getAsRecordType()) { 3652 if (FDTTy->getDecl()->hasFlexibleArrayMember()) { 3653 // If this is a member of a union, then entire union becomes "flexible". 3654 if (Record && Record->isUnion()) { 3655 Record->setHasFlexibleArrayMember(true); 3656 } else { 3657 // If this is a struct/class and this is not the last element, reject 3658 // it. Note that GCC supports variable sized arrays in the middle of 3659 // structures. 3660 if (i != NumFields-1) { 3661 Diag(FD->getLocation(), diag::err_variable_sized_type_in_struct) 3662 << FD->getDeclName(); 3663 FD->setInvalidDecl(); 3664 EnclosingDecl->setInvalidDecl(); 3665 continue; 3666 } 3667 // We support flexible arrays at the end of structs in other structs 3668 // as an extension. 3669 Diag(FD->getLocation(), diag::ext_flexible_array_in_struct) 3670 << FD->getDeclName(); 3671 if (Record) 3672 Record->setHasFlexibleArrayMember(true); 3673 } 3674 } 3675 } 3676 /// A field cannot be an Objective-c object 3677 if (FDTy->isObjCInterfaceType()) { 3678 Diag(FD->getLocation(), diag::err_statically_allocated_object) 3679 << FD->getDeclName(); 3680 FD->setInvalidDecl(); 3681 EnclosingDecl->setInvalidDecl(); 3682 continue; 3683 } 3684 // Keep track of the number of named members. 3685 if (FD->getIdentifier()) 3686 ++NumNamedMembers; 3687 } 3688 3689 // Okay, we successfully defined 'Record'. 3690 if (Record) { 3691 Record->completeDefinition(Context); 3692 } else { 3693 ObjCIvarDecl **ClsFields = reinterpret_cast<ObjCIvarDecl**>(&RecFields[0]); 3694 if (ObjCInterfaceDecl *ID = dyn_cast<ObjCInterfaceDecl>(EnclosingDecl)) { 3695 ID->addInstanceVariablesToClass(ClsFields, RecFields.size(), RBrac); 3696 // Must enforce the rule that ivars in the base classes may not be 3697 // duplicates. 3698 if (ID->getSuperClass()) { 3699 for (ObjCInterfaceDecl::ivar_iterator IVI = ID->ivar_begin(), 3700 IVE = ID->ivar_end(); IVI != IVE; ++IVI) { 3701 ObjCIvarDecl* Ivar = (*IVI); 3702 IdentifierInfo *II = Ivar->getIdentifier(); 3703 ObjCIvarDecl* prevIvar = ID->getSuperClass()->lookupInstanceVariable(II); 3704 if (prevIvar) { 3705 Diag(Ivar->getLocation(), diag::err_duplicate_member) << II; 3706 Diag(prevIvar->getLocation(), diag::note_previous_declaration); 3707 } 3708 } 3709 } 3710 } 3711 else if (ObjCImplementationDecl *IMPDecl = 3712 dyn_cast<ObjCImplementationDecl>(EnclosingDecl)) { 3713 assert(IMPDecl && "ActOnFields - missing ObjCImplementationDecl"); 3714 IMPDecl->ObjCAddInstanceVariablesToClassImpl(ClsFields, RecFields.size()); 3715 CheckImplementationIvars(IMPDecl, ClsFields, RecFields.size(), RBrac); 3716 } 3717 } 3718 3719 if (Attr) 3720 ProcessDeclAttributeList(Record, Attr); 3721} 3722 3723Sema::DeclTy *Sema::ActOnEnumConstant(Scope *S, DeclTy *theEnumDecl, 3724 DeclTy *lastEnumConst, 3725 SourceLocation IdLoc, IdentifierInfo *Id, 3726 SourceLocation EqualLoc, ExprTy *val) { 3727 EnumDecl *TheEnumDecl = cast<EnumDecl>(static_cast<Decl*>(theEnumDecl)); 3728 EnumConstantDecl *LastEnumConst = 3729 cast_or_null<EnumConstantDecl>(static_cast<Decl*>(lastEnumConst)); 3730 Expr *Val = static_cast<Expr*>(val); 3731 3732 // The scope passed in may not be a decl scope. Zip up the scope tree until 3733 // we find one that is. 3734 S = getNonFieldDeclScope(S); 3735 3736 // Verify that there isn't already something declared with this name in this 3737 // scope. 3738 NamedDecl *PrevDecl = LookupName(S, Id, LookupOrdinaryName); 3739 if (PrevDecl && PrevDecl->isTemplateParameter()) { 3740 // Maybe we will complain about the shadowed template parameter. 3741 DiagnoseTemplateParameterShadow(IdLoc, PrevDecl); 3742 // Just pretend that we didn't see the previous declaration. 3743 PrevDecl = 0; 3744 } 3745 3746 if (PrevDecl) { 3747 // When in C++, we may get a TagDecl with the same name; in this case the 3748 // enum constant will 'hide' the tag. 3749 assert((getLangOptions().CPlusPlus || !isa<TagDecl>(PrevDecl)) && 3750 "Received TagDecl when not in C++!"); 3751 if (!isa<TagDecl>(PrevDecl) && isDeclInScope(PrevDecl, CurContext, S)) { 3752 if (isa<EnumConstantDecl>(PrevDecl)) 3753 Diag(IdLoc, diag::err_redefinition_of_enumerator) << Id; 3754 else 3755 Diag(IdLoc, diag::err_redefinition) << Id; 3756 Diag(PrevDecl->getLocation(), diag::note_previous_definition); 3757 Val->Destroy(Context); 3758 return 0; 3759 } 3760 } 3761 3762 llvm::APSInt EnumVal(32); 3763 QualType EltTy; 3764 if (Val) { 3765 // Make sure to promote the operand type to int. 3766 UsualUnaryConversions(Val); 3767 3768 // C99 6.7.2.2p2: Make sure we have an integer constant expression. 3769 SourceLocation ExpLoc; 3770 if (VerifyIntegerConstantExpression(Val, &EnumVal)) { 3771 Val->Destroy(Context); 3772 Val = 0; // Just forget about it. 3773 } else { 3774 EltTy = Val->getType(); 3775 } 3776 } 3777 3778 if (!Val) { 3779 if (LastEnumConst) { 3780 // Assign the last value + 1. 3781 EnumVal = LastEnumConst->getInitVal(); 3782 ++EnumVal; 3783 3784 // Check for overflow on increment. 3785 if (EnumVal < LastEnumConst->getInitVal()) 3786 Diag(IdLoc, diag::warn_enum_value_overflow); 3787 3788 EltTy = LastEnumConst->getType(); 3789 } else { 3790 // First value, set to zero. 3791 EltTy = Context.IntTy; 3792 EnumVal.zextOrTrunc(static_cast<uint32_t>(Context.getTypeSize(EltTy))); 3793 } 3794 } 3795 3796 EnumConstantDecl *New = 3797 EnumConstantDecl::Create(Context, TheEnumDecl, IdLoc, Id, EltTy, 3798 Val, EnumVal); 3799 3800 // Register this decl in the current scope stack. 3801 PushOnScopeChains(New, S); 3802 3803 return New; 3804} 3805 3806// FIXME: For consistency with ActOnFields(), we should have the parser 3807// pass in the source location for the left/right braces. 3808void Sema::ActOnEnumBody(SourceLocation EnumLoc, DeclTy *EnumDeclX, 3809 DeclTy **Elements, unsigned NumElements) { 3810 EnumDecl *Enum = cast<EnumDecl>(static_cast<Decl*>(EnumDeclX)); 3811 QualType EnumType = Context.getTypeDeclType(Enum); 3812 3813 // TODO: If the result value doesn't fit in an int, it must be a long or long 3814 // long value. ISO C does not support this, but GCC does as an extension, 3815 // emit a warning. 3816 unsigned IntWidth = Context.Target.getIntWidth(); 3817 3818 // Verify that all the values are okay, compute the size of the values, and 3819 // reverse the list. 3820 unsigned NumNegativeBits = 0; 3821 unsigned NumPositiveBits = 0; 3822 3823 // Keep track of whether all elements have type int. 3824 bool AllElementsInt = true; 3825 3826 for (unsigned i = 0; i != NumElements; ++i) { 3827 EnumConstantDecl *ECD = 3828 cast_or_null<EnumConstantDecl>(static_cast<Decl*>(Elements[i])); 3829 if (!ECD) continue; // Already issued a diagnostic. 3830 3831 // If the enum value doesn't fit in an int, emit an extension warning. 3832 const llvm::APSInt &InitVal = ECD->getInitVal(); 3833 assert(InitVal.getBitWidth() >= IntWidth && 3834 "Should have promoted value to int"); 3835 if (InitVal.getBitWidth() > IntWidth) { 3836 llvm::APSInt V(InitVal); 3837 V.trunc(IntWidth); 3838 V.extend(InitVal.getBitWidth()); 3839 if (V != InitVal) 3840 Diag(ECD->getLocation(), diag::ext_enum_value_not_int) 3841 << InitVal.toString(10); 3842 } 3843 3844 // Keep track of the size of positive and negative values. 3845 if (InitVal.isUnsigned() || InitVal.isNonNegative()) 3846 NumPositiveBits = std::max(NumPositiveBits, 3847 (unsigned)InitVal.getActiveBits()); 3848 else 3849 NumNegativeBits = std::max(NumNegativeBits, 3850 (unsigned)InitVal.getMinSignedBits()); 3851 3852 // Keep track of whether every enum element has type int (very commmon). 3853 if (AllElementsInt) 3854 AllElementsInt = ECD->getType() == Context.IntTy; 3855 } 3856 3857 // Figure out the type that should be used for this enum. 3858 // FIXME: Support attribute(packed) on enums and -fshort-enums. 3859 QualType BestType; 3860 unsigned BestWidth; 3861 3862 if (NumNegativeBits) { 3863 // If there is a negative value, figure out the smallest integer type (of 3864 // int/long/longlong) that fits. 3865 if (NumNegativeBits <= IntWidth && NumPositiveBits < IntWidth) { 3866 BestType = Context.IntTy; 3867 BestWidth = IntWidth; 3868 } else { 3869 BestWidth = Context.Target.getLongWidth(); 3870 3871 if (NumNegativeBits <= BestWidth && NumPositiveBits < BestWidth) 3872 BestType = Context.LongTy; 3873 else { 3874 BestWidth = Context.Target.getLongLongWidth(); 3875 3876 if (NumNegativeBits > BestWidth || NumPositiveBits >= BestWidth) 3877 Diag(Enum->getLocation(), diag::warn_enum_too_large); 3878 BestType = Context.LongLongTy; 3879 } 3880 } 3881 } else { 3882 // If there is no negative value, figure out which of uint, ulong, ulonglong 3883 // fits. 3884 if (NumPositiveBits <= IntWidth) { 3885 BestType = Context.UnsignedIntTy; 3886 BestWidth = IntWidth; 3887 } else if (NumPositiveBits <= 3888 (BestWidth = Context.Target.getLongWidth())) { 3889 BestType = Context.UnsignedLongTy; 3890 } else { 3891 BestWidth = Context.Target.getLongLongWidth(); 3892 assert(NumPositiveBits <= BestWidth && 3893 "How could an initializer get larger than ULL?"); 3894 BestType = Context.UnsignedLongLongTy; 3895 } 3896 } 3897 3898 // Loop over all of the enumerator constants, changing their types to match 3899 // the type of the enum if needed. 3900 for (unsigned i = 0; i != NumElements; ++i) { 3901 EnumConstantDecl *ECD = 3902 cast_or_null<EnumConstantDecl>(static_cast<Decl*>(Elements[i])); 3903 if (!ECD) continue; // Already issued a diagnostic. 3904 3905 // Standard C says the enumerators have int type, but we allow, as an 3906 // extension, the enumerators to be larger than int size. If each 3907 // enumerator value fits in an int, type it as an int, otherwise type it the 3908 // same as the enumerator decl itself. This means that in "enum { X = 1U }" 3909 // that X has type 'int', not 'unsigned'. 3910 if (ECD->getType() == Context.IntTy) { 3911 // Make sure the init value is signed. 3912 llvm::APSInt IV = ECD->getInitVal(); 3913 IV.setIsSigned(true); 3914 ECD->setInitVal(IV); 3915 3916 if (getLangOptions().CPlusPlus) 3917 // C++ [dcl.enum]p4: Following the closing brace of an 3918 // enum-specifier, each enumerator has the type of its 3919 // enumeration. 3920 ECD->setType(EnumType); 3921 continue; // Already int type. 3922 } 3923 3924 // Determine whether the value fits into an int. 3925 llvm::APSInt InitVal = ECD->getInitVal(); 3926 bool FitsInInt; 3927 if (InitVal.isUnsigned() || !InitVal.isNegative()) 3928 FitsInInt = InitVal.getActiveBits() < IntWidth; 3929 else 3930 FitsInInt = InitVal.getMinSignedBits() <= IntWidth; 3931 3932 // If it fits into an integer type, force it. Otherwise force it to match 3933 // the enum decl type. 3934 QualType NewTy; 3935 unsigned NewWidth; 3936 bool NewSign; 3937 if (FitsInInt) { 3938 NewTy = Context.IntTy; 3939 NewWidth = IntWidth; 3940 NewSign = true; 3941 } else if (ECD->getType() == BestType) { 3942 // Already the right type! 3943 if (getLangOptions().CPlusPlus) 3944 // C++ [dcl.enum]p4: Following the closing brace of an 3945 // enum-specifier, each enumerator has the type of its 3946 // enumeration. 3947 ECD->setType(EnumType); 3948 continue; 3949 } else { 3950 NewTy = BestType; 3951 NewWidth = BestWidth; 3952 NewSign = BestType->isSignedIntegerType(); 3953 } 3954 3955 // Adjust the APSInt value. 3956 InitVal.extOrTrunc(NewWidth); 3957 InitVal.setIsSigned(NewSign); 3958 ECD->setInitVal(InitVal); 3959 3960 // Adjust the Expr initializer and type. 3961 if (ECD->getInitExpr()) 3962 ECD->setInitExpr(new (Context) ImplicitCastExpr(NewTy, ECD->getInitExpr(), 3963 /*isLvalue=*/false)); 3964 if (getLangOptions().CPlusPlus) 3965 // C++ [dcl.enum]p4: Following the closing brace of an 3966 // enum-specifier, each enumerator has the type of its 3967 // enumeration. 3968 ECD->setType(EnumType); 3969 else 3970 ECD->setType(NewTy); 3971 } 3972 3973 Enum->completeDefinition(Context, BestType); 3974} 3975 3976Sema::DeclTy *Sema::ActOnFileScopeAsmDecl(SourceLocation Loc, 3977 ExprArg expr) { 3978 StringLiteral *AsmString = cast<StringLiteral>((Expr*)expr.release()); 3979 3980 return FileScopeAsmDecl::Create(Context, CurContext, Loc, AsmString); 3981} 3982 3983