SemaDecl.cpp revision 9add31798f621f843233dbff8bba103fca64447b
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 if (Decl *D = dyn_cast<Decl>(DC)) 109 return D->getLexicalDeclContext(); 110 111 return DC->getLexicalParent(); 112} 113 114void Sema::PushDeclContext(Scope *S, DeclContext *DC) { 115 assert(getContainingDC(DC) == CurContext && 116 "The next DeclContext should be lexically contained in the current one."); 117 CurContext = DC; 118 S->setEntity(DC); 119} 120 121void Sema::PopDeclContext() { 122 assert(CurContext && "DeclContext imbalance!"); 123 124 CurContext = getContainingDC(CurContext); 125} 126 127/// \brief Determine whether we allow overloading of the function 128/// PrevDecl with another declaration. 129/// 130/// This routine determines whether overloading is possible, not 131/// whether some new function is actually an overload. It will return 132/// true in C++ (where we can always provide overloads) or, as an 133/// extension, in C when the previous function is already an 134/// overloaded function declaration or has the "overloadable" 135/// attribute. 136static bool AllowOverloadingOfFunction(Decl *PrevDecl, ASTContext &Context) { 137 if (Context.getLangOptions().CPlusPlus) 138 return true; 139 140 if (isa<OverloadedFunctionDecl>(PrevDecl)) 141 return true; 142 143 return PrevDecl->getAttr<OverloadableAttr>() != 0; 144} 145 146/// Add this decl to the scope shadowed decl chains. 147void Sema::PushOnScopeChains(NamedDecl *D, Scope *S) { 148 // Move up the scope chain until we find the nearest enclosing 149 // non-transparent context. The declaration will be introduced into this 150 // scope. 151 while (S->getEntity() && 152 ((DeclContext *)S->getEntity())->isTransparentContext()) 153 S = S->getParent(); 154 155 S->AddDecl(D); 156 157 // Add scoped declarations into their context, so that they can be 158 // found later. Declarations without a context won't be inserted 159 // into any context. 160 CurContext->addDecl(D); 161 162 // C++ [basic.scope]p4: 163 // -- exactly one declaration shall declare a class name or 164 // enumeration name that is not a typedef name and the other 165 // declarations shall all refer to the same object or 166 // enumerator, or all refer to functions and function templates; 167 // in this case the class name or enumeration name is hidden. 168 if (TagDecl *TD = dyn_cast<TagDecl>(D)) { 169 // We are pushing the name of a tag (enum or class). 170 if (CurContext->getLookupContext() 171 == TD->getDeclContext()->getLookupContext()) { 172 // We're pushing the tag into the current context, which might 173 // require some reshuffling in the identifier resolver. 174 IdentifierResolver::iterator 175 I = IdResolver.begin(TD->getDeclName()), 176 IEnd = IdResolver.end(); 177 if (I != IEnd && isDeclInScope(*I, CurContext, S)) { 178 NamedDecl *PrevDecl = *I; 179 for (; I != IEnd && isDeclInScope(*I, CurContext, S); 180 PrevDecl = *I, ++I) { 181 if (TD->declarationReplaces(*I)) { 182 // This is a redeclaration. Remove it from the chain and 183 // break out, so that we'll add in the shadowed 184 // declaration. 185 S->RemoveDecl(*I); 186 if (PrevDecl == *I) { 187 IdResolver.RemoveDecl(*I); 188 IdResolver.AddDecl(TD); 189 return; 190 } else { 191 IdResolver.RemoveDecl(*I); 192 break; 193 } 194 } 195 } 196 197 // There is already a declaration with the same name in the same 198 // scope, which is not a tag declaration. It must be found 199 // before we find the new declaration, so insert the new 200 // declaration at the end of the chain. 201 IdResolver.AddShadowedDecl(TD, PrevDecl); 202 203 return; 204 } 205 } 206 } else if (isa<FunctionDecl>(D) && 207 AllowOverloadingOfFunction(D, Context)) { 208 // We are pushing the name of a function, which might be an 209 // overloaded name. 210 FunctionDecl *FD = cast<FunctionDecl>(D); 211 IdentifierResolver::iterator Redecl 212 = std::find_if(IdResolver.begin(FD->getDeclName()), 213 IdResolver.end(), 214 std::bind1st(std::mem_fun(&NamedDecl::declarationReplaces), 215 FD)); 216 if (Redecl != IdResolver.end()) { 217 // There is already a declaration of a function on our 218 // IdResolver chain. Replace it with this declaration. 219 S->RemoveDecl(*Redecl); 220 IdResolver.RemoveDecl(*Redecl); 221 } 222 } 223 224 IdResolver.AddDecl(D); 225} 226 227void Sema::ActOnPopScope(SourceLocation Loc, Scope *S) { 228 if (S->decl_empty()) return; 229 assert((S->getFlags() & (Scope::DeclScope | Scope::TemplateParamScope)) && 230 "Scope shouldn't contain decls!"); 231 232 for (Scope::decl_iterator I = S->decl_begin(), E = S->decl_end(); 233 I != E; ++I) { 234 Decl *TmpD = static_cast<Decl*>(*I); 235 assert(TmpD && "This decl didn't get pushed??"); 236 237 assert(isa<NamedDecl>(TmpD) && "Decl isn't NamedDecl?"); 238 NamedDecl *D = cast<NamedDecl>(TmpD); 239 240 if (!D->getDeclName()) continue; 241 242 // Remove this name from our lexical scope. 243 IdResolver.RemoveDecl(D); 244 } 245} 246 247/// getObjCInterfaceDecl - Look up a for a class declaration in the scope. 248/// return 0 if one not found. 249ObjCInterfaceDecl *Sema::getObjCInterfaceDecl(IdentifierInfo *Id) { 250 // The third "scope" argument is 0 since we aren't enabling lazy built-in 251 // creation from this context. 252 NamedDecl *IDecl = LookupName(TUScope, Id, LookupOrdinaryName); 253 254 return dyn_cast_or_null<ObjCInterfaceDecl>(IDecl); 255} 256 257/// getNonFieldDeclScope - Retrieves the innermost scope, starting 258/// from S, where a non-field would be declared. This routine copes 259/// with the difference between C and C++ scoping rules in structs and 260/// unions. For example, the following code is well-formed in C but 261/// ill-formed in C++: 262/// @code 263/// struct S6 { 264/// enum { BAR } e; 265/// }; 266/// 267/// void test_S6() { 268/// struct S6 a; 269/// a.e = BAR; 270/// } 271/// @endcode 272/// For the declaration of BAR, this routine will return a different 273/// scope. The scope S will be the scope of the unnamed enumeration 274/// within S6. In C++, this routine will return the scope associated 275/// with S6, because the enumeration's scope is a transparent 276/// context but structures can contain non-field names. In C, this 277/// routine will return the translation unit scope, since the 278/// enumeration's scope is a transparent context and structures cannot 279/// contain non-field names. 280Scope *Sema::getNonFieldDeclScope(Scope *S) { 281 while (((S->getFlags() & Scope::DeclScope) == 0) || 282 (S->getEntity() && 283 ((DeclContext *)S->getEntity())->isTransparentContext()) || 284 (S->isClassScope() && !getLangOptions().CPlusPlus)) 285 S = S->getParent(); 286 return S; 287} 288 289void Sema::InitBuiltinVaListType() { 290 if (!Context.getBuiltinVaListType().isNull()) 291 return; 292 293 IdentifierInfo *VaIdent = &Context.Idents.get("__builtin_va_list"); 294 NamedDecl *VaDecl = LookupName(TUScope, VaIdent, LookupOrdinaryName); 295 TypedefDecl *VaTypedef = cast<TypedefDecl>(VaDecl); 296 Context.setBuiltinVaListType(Context.getTypedefType(VaTypedef)); 297} 298 299/// LazilyCreateBuiltin - The specified Builtin-ID was first used at 300/// file scope. lazily create a decl for it. ForRedeclaration is true 301/// if we're creating this built-in in anticipation of redeclaring the 302/// built-in. 303NamedDecl *Sema::LazilyCreateBuiltin(IdentifierInfo *II, unsigned bid, 304 Scope *S, bool ForRedeclaration, 305 SourceLocation Loc) { 306 Builtin::ID BID = (Builtin::ID)bid; 307 308 if (Context.BuiltinInfo.hasVAListUse(BID)) 309 InitBuiltinVaListType(); 310 311 Builtin::Context::GetBuiltinTypeError Error; 312 QualType R = Context.BuiltinInfo.GetBuiltinType(BID, Context, Error); 313 switch (Error) { 314 case Builtin::Context::GE_None: 315 // Okay 316 break; 317 318 case Builtin::Context::GE_Missing_FILE: 319 if (ForRedeclaration) 320 Diag(Loc, diag::err_implicit_decl_requires_stdio) 321 << Context.BuiltinInfo.GetName(BID); 322 return 0; 323 } 324 325 if (!ForRedeclaration && Context.BuiltinInfo.isPredefinedLibFunction(BID)) { 326 Diag(Loc, diag::ext_implicit_lib_function_decl) 327 << Context.BuiltinInfo.GetName(BID) 328 << R; 329 if (Context.BuiltinInfo.getHeaderName(BID) && 330 Diags.getDiagnosticMapping(diag::ext_implicit_lib_function_decl) 331 != diag::MAP_IGNORE) 332 Diag(Loc, diag::note_please_include_header) 333 << Context.BuiltinInfo.getHeaderName(BID) 334 << Context.BuiltinInfo.GetName(BID); 335 } 336 337 FunctionDecl *New = FunctionDecl::Create(Context, 338 Context.getTranslationUnitDecl(), 339 Loc, II, R, 340 FunctionDecl::Extern, false); 341 New->setImplicit(); 342 343 // Create Decl objects for each parameter, adding them to the 344 // FunctionDecl. 345 if (FunctionTypeProto *FT = dyn_cast<FunctionTypeProto>(R)) { 346 llvm::SmallVector<ParmVarDecl*, 16> Params; 347 for (unsigned i = 0, e = FT->getNumArgs(); i != e; ++i) 348 Params.push_back(ParmVarDecl::Create(Context, New, SourceLocation(), 0, 349 FT->getArgType(i), VarDecl::None, 0)); 350 New->setParams(Context, &Params[0], Params.size()); 351 } 352 353 AddKnownFunctionAttributes(New); 354 355 // TUScope is the translation-unit scope to insert this function into. 356 // FIXME: This is hideous. We need to teach PushOnScopeChains to 357 // relate Scopes to DeclContexts, and probably eliminate CurContext 358 // entirely, but we're not there yet. 359 DeclContext *SavedContext = CurContext; 360 CurContext = Context.getTranslationUnitDecl(); 361 PushOnScopeChains(New, TUScope); 362 CurContext = SavedContext; 363 return New; 364} 365 366/// GetStdNamespace - This method gets the C++ "std" namespace. This is where 367/// everything from the standard library is defined. 368NamespaceDecl *Sema::GetStdNamespace() { 369 if (!StdNamespace) { 370 IdentifierInfo *StdIdent = &PP.getIdentifierTable().get("std"); 371 DeclContext *Global = Context.getTranslationUnitDecl(); 372 Decl *Std = LookupQualifiedName(Global, StdIdent, LookupNamespaceName); 373 StdNamespace = dyn_cast_or_null<NamespaceDecl>(Std); 374 } 375 return StdNamespace; 376} 377 378/// MergeTypeDefDecl - We just parsed a typedef 'New' which has the 379/// same name and scope as a previous declaration 'Old'. Figure out 380/// how to resolve this situation, merging decls or emitting 381/// diagnostics as appropriate. Returns true if there was an error, 382/// false otherwise. 383/// 384bool Sema::MergeTypeDefDecl(TypedefDecl *New, Decl *OldD) { 385 bool objc_types = false; 386 // Allow multiple definitions for ObjC built-in typedefs. 387 // FIXME: Verify the underlying types are equivalent! 388 if (getLangOptions().ObjC1) { 389 const IdentifierInfo *TypeID = New->getIdentifier(); 390 switch (TypeID->getLength()) { 391 default: break; 392 case 2: 393 if (!TypeID->isStr("id")) 394 break; 395 Context.setObjCIdType(New); 396 objc_types = true; 397 break; 398 case 5: 399 if (!TypeID->isStr("Class")) 400 break; 401 Context.setObjCClassType(New); 402 objc_types = true; 403 return false; 404 case 3: 405 if (!TypeID->isStr("SEL")) 406 break; 407 Context.setObjCSelType(New); 408 objc_types = true; 409 return false; 410 case 8: 411 if (!TypeID->isStr("Protocol")) 412 break; 413 Context.setObjCProtoType(New->getUnderlyingType()); 414 objc_types = true; 415 return false; 416 } 417 // Fall through - the typedef name was not a builtin type. 418 } 419 // Verify the old decl was also a type. 420 TypeDecl *Old = dyn_cast<TypeDecl>(OldD); 421 if (!Old) { 422 Diag(New->getLocation(), diag::err_redefinition_different_kind) 423 << New->getDeclName(); 424 if (!objc_types) 425 Diag(OldD->getLocation(), diag::note_previous_definition); 426 return true; 427 } 428 429 // Determine the "old" type we'll use for checking and diagnostics. 430 QualType OldType; 431 if (TypedefDecl *OldTypedef = dyn_cast<TypedefDecl>(Old)) 432 OldType = OldTypedef->getUnderlyingType(); 433 else 434 OldType = Context.getTypeDeclType(Old); 435 436 // If the typedef types are not identical, reject them in all languages and 437 // with any extensions enabled. 438 439 if (OldType != New->getUnderlyingType() && 440 Context.getCanonicalType(OldType) != 441 Context.getCanonicalType(New->getUnderlyingType())) { 442 Diag(New->getLocation(), diag::err_redefinition_different_typedef) 443 << New->getUnderlyingType() << OldType; 444 if (!objc_types) 445 Diag(Old->getLocation(), diag::note_previous_definition); 446 return true; 447 } 448 if (objc_types) return false; 449 if (getLangOptions().Microsoft) return false; 450 451 // C++ [dcl.typedef]p2: 452 // In a given non-class scope, a typedef specifier can be used to 453 // redefine the name of any type declared in that scope to refer 454 // to the type to which it already refers. 455 if (getLangOptions().CPlusPlus && !isa<CXXRecordDecl>(CurContext)) 456 return false; 457 458 // In C, redeclaration of a type is a constraint violation (6.7.2.3p1). 459 // Apparently GCC, Intel, and Sun all silently ignore the redeclaration if 460 // *either* declaration is in a system header. The code below implements 461 // this adhoc compatibility rule. FIXME: The following code will not 462 // work properly when compiling ".i" files (containing preprocessed output). 463 if (PP.getDiagnostics().getSuppressSystemWarnings()) { 464 SourceManager &SrcMgr = Context.getSourceManager(); 465 if (SrcMgr.isInSystemHeader(Old->getLocation())) 466 return false; 467 if (SrcMgr.isInSystemHeader(New->getLocation())) 468 return false; 469 } 470 471 Diag(New->getLocation(), diag::err_redefinition) << New->getDeclName(); 472 Diag(Old->getLocation(), diag::note_previous_definition); 473 return true; 474} 475 476/// DeclhasAttr - returns true if decl Declaration already has the target 477/// attribute. 478static bool DeclHasAttr(const Decl *decl, const Attr *target) { 479 for (const Attr *attr = decl->getAttrs(); attr; attr = attr->getNext()) 480 if (attr->getKind() == target->getKind()) 481 return true; 482 483 return false; 484} 485 486/// MergeAttributes - append attributes from the Old decl to the New one. 487static void MergeAttributes(Decl *New, Decl *Old) { 488 Attr *attr = const_cast<Attr*>(Old->getAttrs()), *tmp; 489 490 while (attr) { 491 tmp = attr; 492 attr = attr->getNext(); 493 494 if (!DeclHasAttr(New, tmp) && tmp->isMerged()) { 495 tmp->setInherited(true); 496 New->addAttr(tmp); 497 } else { 498 tmp->setNext(0); 499 delete(tmp); 500 } 501 } 502 503 Old->invalidateAttrs(); 504} 505 506/// MergeFunctionDecl - We just parsed a function 'New' from 507/// declarator D which has the same name and scope as a previous 508/// declaration 'Old'. Figure out how to resolve this situation, 509/// merging decls or emitting diagnostics as appropriate. 510/// 511/// In C++, New and Old must be declarations that are not 512/// overloaded. Use IsOverload to determine whether New and Old are 513/// overloaded, and to select the Old declaration that New should be 514/// merged with. 515/// 516/// Returns true if there was an error, false otherwise. 517bool Sema::MergeFunctionDecl(FunctionDecl *New, Decl *OldD) { 518 assert(!isa<OverloadedFunctionDecl>(OldD) && 519 "Cannot merge with an overloaded function declaration"); 520 521 // Verify the old decl was also a function. 522 FunctionDecl *Old = dyn_cast<FunctionDecl>(OldD); 523 if (!Old) { 524 Diag(New->getLocation(), diag::err_redefinition_different_kind) 525 << New->getDeclName(); 526 Diag(OldD->getLocation(), diag::note_previous_definition); 527 return true; 528 } 529 530 // Determine whether the previous declaration was a definition, 531 // implicit declaration, or a declaration. 532 diag::kind PrevDiag; 533 if (Old->isThisDeclarationADefinition()) 534 PrevDiag = diag::note_previous_definition; 535 else if (Old->isImplicit()) 536 PrevDiag = diag::note_previous_implicit_declaration; 537 else 538 PrevDiag = diag::note_previous_declaration; 539 540 QualType OldQType = Context.getCanonicalType(Old->getType()); 541 QualType NewQType = Context.getCanonicalType(New->getType()); 542 543 if (getLangOptions().CPlusPlus) { 544 // (C++98 13.1p2): 545 // Certain function declarations cannot be overloaded: 546 // -- Function declarations that differ only in the return type 547 // cannot be overloaded. 548 QualType OldReturnType 549 = cast<FunctionType>(OldQType.getTypePtr())->getResultType(); 550 QualType NewReturnType 551 = cast<FunctionType>(NewQType.getTypePtr())->getResultType(); 552 if (OldReturnType != NewReturnType) { 553 Diag(New->getLocation(), diag::err_ovl_diff_return_type); 554 Diag(Old->getLocation(), PrevDiag) << Old << Old->getType(); 555 return true; 556 } 557 558 const CXXMethodDecl* OldMethod = dyn_cast<CXXMethodDecl>(Old); 559 const CXXMethodDecl* NewMethod = dyn_cast<CXXMethodDecl>(New); 560 if (OldMethod && NewMethod) { 561 // -- Member function declarations with the same name and the 562 // same parameter types cannot be overloaded if any of them 563 // is a static member function declaration. 564 if (OldMethod->isStatic() || NewMethod->isStatic()) { 565 Diag(New->getLocation(), diag::err_ovl_static_nonstatic_member); 566 Diag(Old->getLocation(), PrevDiag) << Old << Old->getType(); 567 return true; 568 } 569 570 // C++ [class.mem]p1: 571 // [...] A member shall not be declared twice in the 572 // member-specification, except that a nested class or member 573 // class template can be declared and then later defined. 574 if (OldMethod->getLexicalDeclContext() == 575 NewMethod->getLexicalDeclContext()) { 576 unsigned NewDiag; 577 if (isa<CXXConstructorDecl>(OldMethod)) 578 NewDiag = diag::err_constructor_redeclared; 579 else if (isa<CXXDestructorDecl>(NewMethod)) 580 NewDiag = diag::err_destructor_redeclared; 581 else if (isa<CXXConversionDecl>(NewMethod)) 582 NewDiag = diag::err_conv_function_redeclared; 583 else 584 NewDiag = diag::err_member_redeclared; 585 586 Diag(New->getLocation(), NewDiag); 587 Diag(Old->getLocation(), PrevDiag) << Old << Old->getType(); 588 } 589 } 590 591 // (C++98 8.3.5p3): 592 // All declarations for a function shall agree exactly in both the 593 // return type and the parameter-type-list. 594 if (OldQType == NewQType) { 595 // We have a redeclaration. 596 MergeAttributes(New, Old); 597 return MergeCXXFunctionDecl(New, Old); 598 } 599 600 // Fall through for conflicting redeclarations and redefinitions. 601 } 602 603 // C: Function types need to be compatible, not identical. This handles 604 // duplicate function decls like "void f(int); void f(enum X);" properly. 605 if (!getLangOptions().CPlusPlus && 606 Context.typesAreCompatible(OldQType, NewQType)) { 607 const FunctionType *NewFuncType = NewQType->getAsFunctionType(); 608 const FunctionTypeProto *OldProto = 0; 609 if (isa<FunctionTypeNoProto>(NewFuncType) && 610 (OldProto = OldQType->getAsFunctionTypeProto())) { 611 // The old declaration provided a function prototype, but the 612 // new declaration does not. Merge in the prototype. 613 llvm::SmallVector<QualType, 16> ParamTypes(OldProto->arg_type_begin(), 614 OldProto->arg_type_end()); 615 NewQType = Context.getFunctionType(NewFuncType->getResultType(), 616 &ParamTypes[0], ParamTypes.size(), 617 OldProto->isVariadic(), 618 OldProto->getTypeQuals()); 619 New->setType(NewQType); 620 New->setInheritedPrototype(); 621 622 // Synthesize a parameter for each argument type. 623 llvm::SmallVector<ParmVarDecl*, 16> Params; 624 for (FunctionTypeProto::arg_type_iterator 625 ParamType = OldProto->arg_type_begin(), 626 ParamEnd = OldProto->arg_type_end(); 627 ParamType != ParamEnd; ++ParamType) { 628 ParmVarDecl *Param = ParmVarDecl::Create(Context, New, 629 SourceLocation(), 0, 630 *ParamType, VarDecl::None, 631 0); 632 Param->setImplicit(); 633 Params.push_back(Param); 634 } 635 636 New->setParams(Context, &Params[0], Params.size()); 637 638 } 639 640 MergeAttributes(New, Old); 641 642 return false; 643 } 644 645 // A function that has already been declared has been redeclared or defined 646 // with a different type- show appropriate diagnostic 647 if (unsigned BuiltinID = Old->getBuiltinID(Context)) { 648 // The user has declared a builtin function with an incompatible 649 // signature. 650 if (Context.BuiltinInfo.isPredefinedLibFunction(BuiltinID)) { 651 // The function the user is redeclaring is a library-defined 652 // function like 'malloc' or 'printf'. Warn about the 653 // redeclaration, then ignore it. 654 Diag(New->getLocation(), diag::warn_redecl_library_builtin) << New; 655 Diag(Old->getLocation(), diag::note_previous_builtin_declaration) 656 << Old << Old->getType(); 657 return false; 658 } 659 660 PrevDiag = diag::note_previous_builtin_declaration; 661 } 662 663 Diag(New->getLocation(), diag::err_conflicting_types) << New->getDeclName(); 664 Diag(Old->getLocation(), PrevDiag) << Old << Old->getType(); 665 return true; 666} 667 668/// Predicate for C "tentative" external object definitions (C99 6.9.2). 669static bool isTentativeDefinition(VarDecl *VD) { 670 if (VD->isFileVarDecl()) 671 return (!VD->getInit() && 672 (VD->getStorageClass() == VarDecl::None || 673 VD->getStorageClass() == VarDecl::Static)); 674 return false; 675} 676 677/// CheckForFileScopedRedefinitions - Make sure we forgo redefinition errors 678/// when dealing with C "tentative" external object definitions (C99 6.9.2). 679void Sema::CheckForFileScopedRedefinitions(Scope *S, VarDecl *VD) { 680 bool VDIsTentative = isTentativeDefinition(VD); 681 bool VDIsIncompleteArray = VD->getType()->isIncompleteArrayType(); 682 683 // FIXME: I don't think this will actually see all of the 684 // redefinitions. Can't we check this property on-the-fly? 685 for (IdentifierResolver::iterator I = IdResolver.begin(VD->getIdentifier()), 686 E = IdResolver.end(); 687 I != E; ++I) { 688 if (*I != VD && isDeclInScope(*I, VD->getDeclContext(), S)) { 689 VarDecl *OldDecl = dyn_cast<VarDecl>(*I); 690 691 // Handle the following case: 692 // int a[10]; 693 // int a[]; - the code below makes sure we set the correct type. 694 // int a[11]; - this is an error, size isn't 10. 695 if (OldDecl && VDIsTentative && VDIsIncompleteArray && 696 OldDecl->getType()->isConstantArrayType()) 697 VD->setType(OldDecl->getType()); 698 699 // Check for "tentative" definitions. We can't accomplish this in 700 // MergeVarDecl since the initializer hasn't been attached. 701 if (!OldDecl || isTentativeDefinition(OldDecl) || VDIsTentative) 702 continue; 703 704 // Handle __private_extern__ just like extern. 705 if (OldDecl->getStorageClass() != VarDecl::Extern && 706 OldDecl->getStorageClass() != VarDecl::PrivateExtern && 707 VD->getStorageClass() != VarDecl::Extern && 708 VD->getStorageClass() != VarDecl::PrivateExtern) { 709 Diag(VD->getLocation(), diag::err_redefinition) << VD->getDeclName(); 710 Diag(OldDecl->getLocation(), diag::note_previous_definition); 711 // One redefinition error is enough. 712 break; 713 } 714 } 715 } 716} 717 718/// MergeVarDecl - We just parsed a variable 'New' which has the same name 719/// and scope as a previous declaration 'Old'. Figure out how to resolve this 720/// situation, merging decls or emitting diagnostics as appropriate. 721/// 722/// Tentative definition rules (C99 6.9.2p2) are checked by 723/// FinalizeDeclaratorGroup. Unfortunately, we can't analyze tentative 724/// definitions here, since the initializer hasn't been attached. 725/// 726bool Sema::MergeVarDecl(VarDecl *New, Decl *OldD) { 727 // Verify the old decl was also a variable. 728 VarDecl *Old = dyn_cast<VarDecl>(OldD); 729 if (!Old) { 730 Diag(New->getLocation(), diag::err_redefinition_different_kind) 731 << New->getDeclName(); 732 Diag(OldD->getLocation(), diag::note_previous_definition); 733 return true; 734 } 735 736 MergeAttributes(New, Old); 737 738 // Merge the types 739 QualType MergedT = Context.mergeTypes(New->getType(), Old->getType()); 740 if (MergedT.isNull()) { 741 Diag(New->getLocation(), diag::err_redefinition_different_type) 742 << New->getDeclName(); 743 Diag(Old->getLocation(), diag::note_previous_definition); 744 return true; 745 } 746 New->setType(MergedT); 747 // C99 6.2.2p4: Check if we have a static decl followed by a non-static. 748 if (New->getStorageClass() == VarDecl::Static && 749 (Old->getStorageClass() == VarDecl::None || 750 Old->getStorageClass() == VarDecl::Extern)) { 751 Diag(New->getLocation(), diag::err_static_non_static) << New->getDeclName(); 752 Diag(Old->getLocation(), diag::note_previous_definition); 753 return true; 754 } 755 // C99 6.2.2p4: Check if we have a non-static decl followed by a static. 756 if (New->getStorageClass() != VarDecl::Static && 757 Old->getStorageClass() == VarDecl::Static) { 758 Diag(New->getLocation(), diag::err_non_static_static) << New->getDeclName(); 759 Diag(Old->getLocation(), diag::note_previous_definition); 760 return true; 761 } 762 // Variables with external linkage are analyzed in FinalizeDeclaratorGroup. 763 if (New->getStorageClass() != VarDecl::Extern && !New->isFileVarDecl()) { 764 Diag(New->getLocation(), diag::err_redefinition) << New->getDeclName(); 765 Diag(Old->getLocation(), diag::note_previous_definition); 766 return true; 767 } 768 return false; 769} 770 771/// CheckParmsForFunctionDef - Check that the parameters of the given 772/// function are appropriate for the definition of a function. This 773/// takes care of any checks that cannot be performed on the 774/// declaration itself, e.g., that the types of each of the function 775/// parameters are complete. 776bool Sema::CheckParmsForFunctionDef(FunctionDecl *FD) { 777 bool HasInvalidParm = false; 778 for (unsigned p = 0, NumParams = FD->getNumParams(); p < NumParams; ++p) { 779 ParmVarDecl *Param = FD->getParamDecl(p); 780 781 // C99 6.7.5.3p4: the parameters in a parameter type list in a 782 // function declarator that is part of a function definition of 783 // that function shall not have incomplete type. 784 if (!Param->isInvalidDecl() && 785 DiagnoseIncompleteType(Param->getLocation(), Param->getType(), 786 diag::err_typecheck_decl_incomplete_type)) { 787 Param->setInvalidDecl(); 788 HasInvalidParm = true; 789 } 790 791 // C99 6.9.1p5: If the declarator includes a parameter type list, the 792 // declaration of each parameter shall include an identifier. 793 if (Param->getIdentifier() == 0 && 794 !Param->isImplicit() && 795 !getLangOptions().CPlusPlus) 796 Diag(Param->getLocation(), diag::err_parameter_name_omitted); 797 } 798 799 return HasInvalidParm; 800} 801 802/// ParsedFreeStandingDeclSpec - This method is invoked when a declspec with 803/// no declarator (e.g. "struct foo;") is parsed. 804Sema::DeclTy *Sema::ParsedFreeStandingDeclSpec(Scope *S, DeclSpec &DS) { 805 TagDecl *Tag = 0; 806 if (DS.getTypeSpecType() == DeclSpec::TST_class || 807 DS.getTypeSpecType() == DeclSpec::TST_struct || 808 DS.getTypeSpecType() == DeclSpec::TST_union || 809 DS.getTypeSpecType() == DeclSpec::TST_enum) 810 Tag = dyn_cast<TagDecl>(static_cast<Decl *>(DS.getTypeRep())); 811 812 if (RecordDecl *Record = dyn_cast_or_null<RecordDecl>(Tag)) { 813 if (!Record->getDeclName() && Record->isDefinition() && 814 DS.getStorageClassSpec() != DeclSpec::SCS_typedef) 815 return BuildAnonymousStructOrUnion(S, DS, Record); 816 817 // Microsoft allows unnamed struct/union fields. Don't complain 818 // about them. 819 // FIXME: Should we support Microsoft's extensions in this area? 820 if (Record->getDeclName() && getLangOptions().Microsoft) 821 return Tag; 822 } 823 824 if (!DS.isMissingDeclaratorOk() && 825 DS.getTypeSpecType() != DeclSpec::TST_error) { 826 // Warn about typedefs of enums without names, since this is an 827 // extension in both Microsoft an GNU. 828 if (DS.getStorageClassSpec() == DeclSpec::SCS_typedef && 829 Tag && isa<EnumDecl>(Tag)) { 830 Diag(DS.getSourceRange().getBegin(), diag::ext_typedef_without_a_name) 831 << DS.getSourceRange(); 832 return Tag; 833 } 834 835 Diag(DS.getSourceRange().getBegin(), diag::err_no_declarators) 836 << DS.getSourceRange(); 837 return 0; 838 } 839 840 return Tag; 841} 842 843/// InjectAnonymousStructOrUnionMembers - Inject the members of the 844/// anonymous struct or union AnonRecord into the owning context Owner 845/// and scope S. This routine will be invoked just after we realize 846/// that an unnamed union or struct is actually an anonymous union or 847/// struct, e.g., 848/// 849/// @code 850/// union { 851/// int i; 852/// float f; 853/// }; // InjectAnonymousStructOrUnionMembers called here to inject i and 854/// // f into the surrounding scope.x 855/// @endcode 856/// 857/// This routine is recursive, injecting the names of nested anonymous 858/// structs/unions into the owning context and scope as well. 859bool Sema::InjectAnonymousStructOrUnionMembers(Scope *S, DeclContext *Owner, 860 RecordDecl *AnonRecord) { 861 bool Invalid = false; 862 for (RecordDecl::field_iterator F = AnonRecord->field_begin(), 863 FEnd = AnonRecord->field_end(); 864 F != FEnd; ++F) { 865 if ((*F)->getDeclName()) { 866 NamedDecl *PrevDecl = LookupQualifiedName(Owner, (*F)->getDeclName(), 867 LookupOrdinaryName, true); 868 if (PrevDecl && !isa<TagDecl>(PrevDecl)) { 869 // C++ [class.union]p2: 870 // The names of the members of an anonymous union shall be 871 // distinct from the names of any other entity in the 872 // scope in which the anonymous union is declared. 873 unsigned diagKind 874 = AnonRecord->isUnion()? diag::err_anonymous_union_member_redecl 875 : diag::err_anonymous_struct_member_redecl; 876 Diag((*F)->getLocation(), diagKind) 877 << (*F)->getDeclName(); 878 Diag(PrevDecl->getLocation(), diag::note_previous_declaration); 879 Invalid = true; 880 } else { 881 // C++ [class.union]p2: 882 // For the purpose of name lookup, after the anonymous union 883 // definition, the members of the anonymous union are 884 // considered to have been defined in the scope in which the 885 // anonymous union is declared. 886 Owner->makeDeclVisibleInContext(*F); 887 S->AddDecl(*F); 888 IdResolver.AddDecl(*F); 889 } 890 } else if (const RecordType *InnerRecordType 891 = (*F)->getType()->getAsRecordType()) { 892 RecordDecl *InnerRecord = InnerRecordType->getDecl(); 893 if (InnerRecord->isAnonymousStructOrUnion()) 894 Invalid = Invalid || 895 InjectAnonymousStructOrUnionMembers(S, Owner, InnerRecord); 896 } 897 } 898 899 return Invalid; 900} 901 902/// ActOnAnonymousStructOrUnion - Handle the declaration of an 903/// anonymous structure or union. Anonymous unions are a C++ feature 904/// (C++ [class.union]) and a GNU C extension; anonymous structures 905/// are a GNU C and GNU C++ extension. 906Sema::DeclTy *Sema::BuildAnonymousStructOrUnion(Scope *S, DeclSpec &DS, 907 RecordDecl *Record) { 908 DeclContext *Owner = Record->getDeclContext(); 909 910 // Diagnose whether this anonymous struct/union is an extension. 911 if (Record->isUnion() && !getLangOptions().CPlusPlus) 912 Diag(Record->getLocation(), diag::ext_anonymous_union); 913 else if (!Record->isUnion()) 914 Diag(Record->getLocation(), diag::ext_anonymous_struct); 915 916 // C and C++ require different kinds of checks for anonymous 917 // structs/unions. 918 bool Invalid = false; 919 if (getLangOptions().CPlusPlus) { 920 const char* PrevSpec = 0; 921 // C++ [class.union]p3: 922 // Anonymous unions declared in a named namespace or in the 923 // global namespace shall be declared static. 924 if (DS.getStorageClassSpec() != DeclSpec::SCS_static && 925 (isa<TranslationUnitDecl>(Owner) || 926 (isa<NamespaceDecl>(Owner) && 927 cast<NamespaceDecl>(Owner)->getDeclName()))) { 928 Diag(Record->getLocation(), diag::err_anonymous_union_not_static); 929 Invalid = true; 930 931 // Recover by adding 'static'. 932 DS.SetStorageClassSpec(DeclSpec::SCS_static, SourceLocation(), PrevSpec); 933 } 934 // C++ [class.union]p3: 935 // A storage class is not allowed in a declaration of an 936 // anonymous union in a class scope. 937 else if (DS.getStorageClassSpec() != DeclSpec::SCS_unspecified && 938 isa<RecordDecl>(Owner)) { 939 Diag(DS.getStorageClassSpecLoc(), 940 diag::err_anonymous_union_with_storage_spec); 941 Invalid = true; 942 943 // Recover by removing the storage specifier. 944 DS.SetStorageClassSpec(DeclSpec::SCS_unspecified, SourceLocation(), 945 PrevSpec); 946 } 947 948 // C++ [class.union]p2: 949 // The member-specification of an anonymous union shall only 950 // define non-static data members. [Note: nested types and 951 // functions cannot be declared within an anonymous union. ] 952 for (DeclContext::decl_iterator Mem = Record->decls_begin(), 953 MemEnd = Record->decls_end(); 954 Mem != MemEnd; ++Mem) { 955 if (FieldDecl *FD = dyn_cast<FieldDecl>(*Mem)) { 956 // C++ [class.union]p3: 957 // An anonymous union shall not have private or protected 958 // members (clause 11). 959 if (FD->getAccess() == AS_protected || FD->getAccess() == AS_private) { 960 Diag(FD->getLocation(), diag::err_anonymous_record_nonpublic_member) 961 << (int)Record->isUnion() << (int)(FD->getAccess() == AS_protected); 962 Invalid = true; 963 } 964 } else if ((*Mem)->isImplicit()) { 965 // Any implicit members are fine. 966 } else if (isa<TagDecl>(*Mem) && (*Mem)->getDeclContext() != Record) { 967 // This is a type that showed up in an 968 // elaborated-type-specifier inside the anonymous struct or 969 // union, but which actually declares a type outside of the 970 // anonymous struct or union. It's okay. 971 } else if (RecordDecl *MemRecord = dyn_cast<RecordDecl>(*Mem)) { 972 if (!MemRecord->isAnonymousStructOrUnion() && 973 MemRecord->getDeclName()) { 974 // This is a nested type declaration. 975 Diag(MemRecord->getLocation(), diag::err_anonymous_record_with_type) 976 << (int)Record->isUnion(); 977 Invalid = true; 978 } 979 } else { 980 // We have something that isn't a non-static data 981 // member. Complain about it. 982 unsigned DK = diag::err_anonymous_record_bad_member; 983 if (isa<TypeDecl>(*Mem)) 984 DK = diag::err_anonymous_record_with_type; 985 else if (isa<FunctionDecl>(*Mem)) 986 DK = diag::err_anonymous_record_with_function; 987 else if (isa<VarDecl>(*Mem)) 988 DK = diag::err_anonymous_record_with_static; 989 Diag((*Mem)->getLocation(), DK) 990 << (int)Record->isUnion(); 991 Invalid = true; 992 } 993 } 994 } else { 995 // FIXME: Check GNU C semantics 996 if (Record->isUnion() && !Owner->isRecord()) { 997 Diag(Record->getLocation(), diag::err_anonymous_union_not_member) 998 << (int)getLangOptions().CPlusPlus; 999 Invalid = true; 1000 } 1001 } 1002 1003 if (!Record->isUnion() && !Owner->isRecord()) { 1004 Diag(Record->getLocation(), diag::err_anonymous_struct_not_member) 1005 << (int)getLangOptions().CPlusPlus; 1006 Invalid = true; 1007 } 1008 1009 // Create a declaration for this anonymous struct/union. 1010 NamedDecl *Anon = 0; 1011 if (RecordDecl *OwningClass = dyn_cast<RecordDecl>(Owner)) { 1012 Anon = FieldDecl::Create(Context, OwningClass, Record->getLocation(), 1013 /*IdentifierInfo=*/0, 1014 Context.getTypeDeclType(Record), 1015 /*BitWidth=*/0, /*Mutable=*/false); 1016 Anon->setAccess(AS_public); 1017 if (getLangOptions().CPlusPlus) 1018 FieldCollector->Add(cast<FieldDecl>(Anon)); 1019 } else { 1020 VarDecl::StorageClass SC; 1021 switch (DS.getStorageClassSpec()) { 1022 default: assert(0 && "Unknown storage class!"); 1023 case DeclSpec::SCS_unspecified: SC = VarDecl::None; break; 1024 case DeclSpec::SCS_extern: SC = VarDecl::Extern; break; 1025 case DeclSpec::SCS_static: SC = VarDecl::Static; break; 1026 case DeclSpec::SCS_auto: SC = VarDecl::Auto; break; 1027 case DeclSpec::SCS_register: SC = VarDecl::Register; break; 1028 case DeclSpec::SCS_private_extern: SC = VarDecl::PrivateExtern; break; 1029 case DeclSpec::SCS_mutable: 1030 // mutable can only appear on non-static class members, so it's always 1031 // an error here 1032 Diag(Record->getLocation(), diag::err_mutable_nonmember); 1033 Invalid = true; 1034 SC = VarDecl::None; 1035 break; 1036 } 1037 1038 Anon = VarDecl::Create(Context, Owner, Record->getLocation(), 1039 /*IdentifierInfo=*/0, 1040 Context.getTypeDeclType(Record), 1041 SC, DS.getSourceRange().getBegin()); 1042 } 1043 Anon->setImplicit(); 1044 1045 // Add the anonymous struct/union object to the current 1046 // context. We'll be referencing this object when we refer to one of 1047 // its members. 1048 Owner->addDecl(Anon); 1049 1050 // Inject the members of the anonymous struct/union into the owning 1051 // context and into the identifier resolver chain for name lookup 1052 // purposes. 1053 if (InjectAnonymousStructOrUnionMembers(S, Owner, Record)) 1054 Invalid = true; 1055 1056 // Mark this as an anonymous struct/union type. Note that we do not 1057 // do this until after we have already checked and injected the 1058 // members of this anonymous struct/union type, because otherwise 1059 // the members could be injected twice: once by DeclContext when it 1060 // builds its lookup table, and once by 1061 // InjectAnonymousStructOrUnionMembers. 1062 Record->setAnonymousStructOrUnion(true); 1063 1064 if (Invalid) 1065 Anon->setInvalidDecl(); 1066 1067 return Anon; 1068} 1069 1070bool Sema::CheckSingleInitializer(Expr *&Init, QualType DeclType, 1071 bool DirectInit) { 1072 // Get the type before calling CheckSingleAssignmentConstraints(), since 1073 // it can promote the expression. 1074 QualType InitType = Init->getType(); 1075 1076 if (getLangOptions().CPlusPlus) { 1077 // FIXME: I dislike this error message. A lot. 1078 if (PerformImplicitConversion(Init, DeclType, "initializing", DirectInit)) 1079 return Diag(Init->getSourceRange().getBegin(), 1080 diag::err_typecheck_convert_incompatible) 1081 << DeclType << Init->getType() << "initializing" 1082 << Init->getSourceRange(); 1083 1084 return false; 1085 } 1086 1087 AssignConvertType ConvTy = CheckSingleAssignmentConstraints(DeclType, Init); 1088 return DiagnoseAssignmentResult(ConvTy, Init->getLocStart(), DeclType, 1089 InitType, Init, "initializing"); 1090} 1091 1092bool Sema::CheckStringLiteralInit(StringLiteral *strLiteral, QualType &DeclT) { 1093 const ArrayType *AT = Context.getAsArrayType(DeclT); 1094 1095 if (const IncompleteArrayType *IAT = dyn_cast<IncompleteArrayType>(AT)) { 1096 // C99 6.7.8p14. We have an array of character type with unknown size 1097 // being initialized to a string literal. 1098 llvm::APSInt ConstVal(32); 1099 ConstVal = strLiteral->getByteLength() + 1; 1100 // Return a new array type (C99 6.7.8p22). 1101 DeclT = Context.getConstantArrayType(IAT->getElementType(), ConstVal, 1102 ArrayType::Normal, 0); 1103 } else { 1104 const ConstantArrayType *CAT = cast<ConstantArrayType>(AT); 1105 // C99 6.7.8p14. We have an array of character type with known size. 1106 // FIXME: Avoid truncation for 64-bit length strings. 1107 if (strLiteral->getByteLength() > (unsigned)CAT->getSize().getZExtValue()) 1108 Diag(strLiteral->getSourceRange().getBegin(), 1109 diag::warn_initializer_string_for_char_array_too_long) 1110 << strLiteral->getSourceRange(); 1111 } 1112 // Set type from "char *" to "constant array of char". 1113 strLiteral->setType(DeclT); 1114 // For now, we always return false (meaning success). 1115 return false; 1116} 1117 1118StringLiteral *Sema::IsStringLiteralInit(Expr *Init, QualType DeclType) { 1119 const ArrayType *AT = Context.getAsArrayType(DeclType); 1120 if (AT && AT->getElementType()->isCharType()) { 1121 return dyn_cast<StringLiteral>(Init->IgnoreParens()); 1122 } 1123 return 0; 1124} 1125 1126bool Sema::CheckInitializerTypes(Expr *&Init, QualType &DeclType, 1127 SourceLocation InitLoc, 1128 DeclarationName InitEntity, 1129 bool DirectInit) { 1130 if (DeclType->isDependentType() || Init->isTypeDependent()) 1131 return false; 1132 1133 // C++ [dcl.init.ref]p1: 1134 // A variable declared to be a T&, that is "reference to type T" 1135 // (8.3.2), shall be initialized by an object, or function, of 1136 // type T or by an object that can be converted into a T. 1137 if (DeclType->isReferenceType()) 1138 return CheckReferenceInit(Init, DeclType, 0, false, DirectInit); 1139 1140 // C99 6.7.8p3: The type of the entity to be initialized shall be an array 1141 // of unknown size ("[]") or an object type that is not a variable array type. 1142 if (const VariableArrayType *VAT = Context.getAsVariableArrayType(DeclType)) 1143 return Diag(InitLoc, diag::err_variable_object_no_init) 1144 << VAT->getSizeExpr()->getSourceRange(); 1145 1146 InitListExpr *InitList = dyn_cast<InitListExpr>(Init); 1147 if (!InitList) { 1148 // FIXME: Handle wide strings 1149 if (StringLiteral *strLiteral = IsStringLiteralInit(Init, DeclType)) 1150 return CheckStringLiteralInit(strLiteral, DeclType); 1151 1152 // C++ [dcl.init]p14: 1153 // -- If the destination type is a (possibly cv-qualified) class 1154 // type: 1155 if (getLangOptions().CPlusPlus && DeclType->isRecordType()) { 1156 QualType DeclTypeC = Context.getCanonicalType(DeclType); 1157 QualType InitTypeC = Context.getCanonicalType(Init->getType()); 1158 1159 // -- If the initialization is direct-initialization, or if it is 1160 // copy-initialization where the cv-unqualified version of the 1161 // source type is the same class as, or a derived class of, the 1162 // class of the destination, constructors are considered. 1163 if ((DeclTypeC.getUnqualifiedType() == InitTypeC.getUnqualifiedType()) || 1164 IsDerivedFrom(InitTypeC, DeclTypeC)) { 1165 CXXConstructorDecl *Constructor 1166 = PerformInitializationByConstructor(DeclType, &Init, 1, 1167 InitLoc, Init->getSourceRange(), 1168 InitEntity, 1169 DirectInit? IK_Direct : IK_Copy); 1170 return Constructor == 0; 1171 } 1172 1173 // -- Otherwise (i.e., for the remaining copy-initialization 1174 // cases), user-defined conversion sequences that can 1175 // convert from the source type to the destination type or 1176 // (when a conversion function is used) to a derived class 1177 // thereof are enumerated as described in 13.3.1.4, and the 1178 // best one is chosen through overload resolution 1179 // (13.3). If the conversion cannot be done or is 1180 // ambiguous, the initialization is ill-formed. The 1181 // function selected is called with the initializer 1182 // expression as its argument; if the function is a 1183 // constructor, the call initializes a temporary of the 1184 // destination type. 1185 // FIXME: We're pretending to do copy elision here; return to 1186 // this when we have ASTs for such things. 1187 if (!PerformImplicitConversion(Init, DeclType, "initializing")) 1188 return false; 1189 1190 if (InitEntity) 1191 return Diag(InitLoc, diag::err_cannot_initialize_decl) 1192 << InitEntity << (int)(Init->isLvalue(Context) == Expr::LV_Valid) 1193 << Init->getType() << Init->getSourceRange(); 1194 else 1195 return Diag(InitLoc, diag::err_cannot_initialize_decl_noname) 1196 << DeclType << (int)(Init->isLvalue(Context) == Expr::LV_Valid) 1197 << Init->getType() << Init->getSourceRange(); 1198 } 1199 1200 // C99 6.7.8p16. 1201 if (DeclType->isArrayType()) 1202 return Diag(Init->getLocStart(), diag::err_array_init_list_required) 1203 << Init->getSourceRange(); 1204 1205 return CheckSingleInitializer(Init, DeclType, DirectInit); 1206 } 1207 1208 bool hadError = CheckInitList(InitList, DeclType); 1209 Init = InitList; 1210 return hadError; 1211} 1212 1213/// GetNameForDeclarator - Determine the full declaration name for the 1214/// given Declarator. 1215DeclarationName Sema::GetNameForDeclarator(Declarator &D) { 1216 switch (D.getKind()) { 1217 case Declarator::DK_Abstract: 1218 assert(D.getIdentifier() == 0 && "abstract declarators have no name"); 1219 return DeclarationName(); 1220 1221 case Declarator::DK_Normal: 1222 assert (D.getIdentifier() != 0 && "normal declarators have an identifier"); 1223 return DeclarationName(D.getIdentifier()); 1224 1225 case Declarator::DK_Constructor: { 1226 QualType Ty = QualType::getFromOpaquePtr(D.getDeclaratorIdType()); 1227 Ty = Context.getCanonicalType(Ty); 1228 return Context.DeclarationNames.getCXXConstructorName(Ty); 1229 } 1230 1231 case Declarator::DK_Destructor: { 1232 QualType Ty = QualType::getFromOpaquePtr(D.getDeclaratorIdType()); 1233 Ty = Context.getCanonicalType(Ty); 1234 return Context.DeclarationNames.getCXXDestructorName(Ty); 1235 } 1236 1237 case Declarator::DK_Conversion: { 1238 // FIXME: We'd like to keep the non-canonical type for diagnostics! 1239 QualType Ty = QualType::getFromOpaquePtr(D.getDeclaratorIdType()); 1240 Ty = Context.getCanonicalType(Ty); 1241 return Context.DeclarationNames.getCXXConversionFunctionName(Ty); 1242 } 1243 1244 case Declarator::DK_Operator: 1245 assert(D.getIdentifier() == 0 && "operator names have no identifier"); 1246 return Context.DeclarationNames.getCXXOperatorName( 1247 D.getOverloadedOperator()); 1248 } 1249 1250 assert(false && "Unknown name kind"); 1251 return DeclarationName(); 1252} 1253 1254/// isNearlyMatchingFunction - Determine whether the C++ functions 1255/// Declaration and Definition are "nearly" matching. This heuristic 1256/// is used to improve diagnostics in the case where an out-of-line 1257/// function definition doesn't match any declaration within 1258/// the class or namespace. 1259static bool isNearlyMatchingFunction(ASTContext &Context, 1260 FunctionDecl *Declaration, 1261 FunctionDecl *Definition) { 1262 if (Declaration->param_size() != Definition->param_size()) 1263 return false; 1264 for (unsigned Idx = 0; Idx < Declaration->param_size(); ++Idx) { 1265 QualType DeclParamTy = Declaration->getParamDecl(Idx)->getType(); 1266 QualType DefParamTy = Definition->getParamDecl(Idx)->getType(); 1267 1268 DeclParamTy = Context.getCanonicalType(DeclParamTy.getNonReferenceType()); 1269 DefParamTy = Context.getCanonicalType(DefParamTy.getNonReferenceType()); 1270 if (DeclParamTy.getUnqualifiedType() != DefParamTy.getUnqualifiedType()) 1271 return false; 1272 } 1273 1274 return true; 1275} 1276 1277Sema::DeclTy * 1278Sema::ActOnDeclarator(Scope *S, Declarator &D, DeclTy *lastDecl, 1279 bool IsFunctionDefinition) { 1280 NamedDecl *LastDeclarator = dyn_cast_or_null<NamedDecl>((Decl *)lastDecl); 1281 DeclarationName Name = GetNameForDeclarator(D); 1282 1283 // All of these full declarators require an identifier. If it doesn't have 1284 // one, the ParsedFreeStandingDeclSpec action should be used. 1285 if (!Name) { 1286 if (!D.getInvalidType()) // Reject this if we think it is valid. 1287 Diag(D.getDeclSpec().getSourceRange().getBegin(), 1288 diag::err_declarator_need_ident) 1289 << D.getDeclSpec().getSourceRange() << D.getSourceRange(); 1290 return 0; 1291 } 1292 1293 // The scope passed in may not be a decl scope. Zip up the scope tree until 1294 // we find one that is. 1295 while ((S->getFlags() & Scope::DeclScope) == 0 || 1296 (S->getFlags() & Scope::TemplateParamScope) != 0) 1297 S = S->getParent(); 1298 1299 DeclContext *DC; 1300 NamedDecl *PrevDecl; 1301 NamedDecl *New; 1302 bool InvalidDecl = false; 1303 1304 // See if this is a redefinition of a variable in the same scope. 1305 if (!D.getCXXScopeSpec().isSet() && !D.getCXXScopeSpec().isInvalid()) { 1306 DC = CurContext; 1307 PrevDecl = LookupName(S, Name, LookupOrdinaryName, true, 1308 D.getDeclSpec().getStorageClassSpec() != 1309 DeclSpec::SCS_static, 1310 D.getIdentifierLoc()); 1311 } else { // Something like "int foo::x;" 1312 DC = static_cast<DeclContext*>(D.getCXXScopeSpec().getScopeRep()); 1313 PrevDecl = LookupQualifiedName(DC, Name, LookupOrdinaryName, true); 1314 1315 // C++ 7.3.1.2p2: 1316 // Members (including explicit specializations of templates) of a named 1317 // namespace can also be defined outside that namespace by explicit 1318 // qualification of the name being defined, provided that the entity being 1319 // defined was already declared in the namespace and the definition appears 1320 // after the point of declaration in a namespace that encloses the 1321 // declarations namespace. 1322 // 1323 // Note that we only check the context at this point. We don't yet 1324 // have enough information to make sure that PrevDecl is actually 1325 // the declaration we want to match. For example, given: 1326 // 1327 // class X { 1328 // void f(); 1329 // void f(float); 1330 // }; 1331 // 1332 // void X::f(int) { } // ill-formed 1333 // 1334 // In this case, PrevDecl will point to the overload set 1335 // containing the two f's declared in X, but neither of them 1336 // matches. 1337 1338 // First check whether we named the global scope. 1339 if (isa<TranslationUnitDecl>(DC)) { 1340 Diag(D.getIdentifierLoc(), diag::err_invalid_declarator_global_scope) 1341 << Name << D.getCXXScopeSpec().getRange(); 1342 } else if (!CurContext->Encloses(DC)) { 1343 // The qualifying scope doesn't enclose the original declaration. 1344 // Emit diagnostic based on current scope. 1345 SourceLocation L = D.getIdentifierLoc(); 1346 SourceRange R = D.getCXXScopeSpec().getRange(); 1347 if (isa<FunctionDecl>(CurContext)) 1348 Diag(L, diag::err_invalid_declarator_in_function) << Name << R; 1349 else 1350 Diag(L, diag::err_invalid_declarator_scope) 1351 << Name << cast<NamedDecl>(DC) << R; 1352 InvalidDecl = true; 1353 } 1354 } 1355 1356 if (PrevDecl && PrevDecl->isTemplateParameter()) { 1357 // Maybe we will complain about the shadowed template parameter. 1358 InvalidDecl = InvalidDecl 1359 || DiagnoseTemplateParameterShadow(D.getIdentifierLoc(), PrevDecl); 1360 // Just pretend that we didn't see the previous declaration. 1361 PrevDecl = 0; 1362 } 1363 1364 // In C++, the previous declaration we find might be a tag type 1365 // (class or enum). In this case, the new declaration will hide the 1366 // tag type. Note that this does does not apply if we're declaring a 1367 // typedef (C++ [dcl.typedef]p4). 1368 if (PrevDecl && PrevDecl->getIdentifierNamespace() == Decl::IDNS_Tag && 1369 D.getDeclSpec().getStorageClassSpec() != DeclSpec::SCS_typedef) 1370 PrevDecl = 0; 1371 1372 QualType R = GetTypeForDeclarator(D, S); 1373 assert(!R.isNull() && "GetTypeForDeclarator() returned null type"); 1374 1375 bool Redeclaration = false; 1376 if (D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_typedef) { 1377 New = ActOnTypedefDeclarator(S, D, DC, R, LastDeclarator, PrevDecl, 1378 InvalidDecl, Redeclaration); 1379 } else if (R.getTypePtr()->isFunctionType()) { 1380 New = ActOnFunctionDeclarator(S, D, DC, R, LastDeclarator, PrevDecl, 1381 IsFunctionDefinition, InvalidDecl, 1382 Redeclaration); 1383 } else { 1384 New = ActOnVariableDeclarator(S, D, DC, R, LastDeclarator, PrevDecl, 1385 InvalidDecl, Redeclaration); 1386 } 1387 1388 if (New == 0) 1389 return 0; 1390 1391 // Set the lexical context. If the declarator has a C++ scope specifier, the 1392 // lexical context will be different from the semantic context. 1393 New->setLexicalDeclContext(CurContext); 1394 1395 // If this has an identifier and is not an invalid redeclaration, 1396 // add it to the scope stack. 1397 if (Name && !(Redeclaration && InvalidDecl)) 1398 PushOnScopeChains(New, S); 1399 // If any semantic error occurred, mark the decl as invalid. 1400 if (D.getInvalidType() || InvalidDecl) 1401 New->setInvalidDecl(); 1402 1403 return New; 1404} 1405 1406NamedDecl* 1407Sema::ActOnTypedefDeclarator(Scope* S, Declarator& D, DeclContext* DC, 1408 QualType R, Decl* LastDeclarator, 1409 Decl* PrevDecl, bool& InvalidDecl, 1410 bool &Redeclaration) { 1411 // Typedef declarators cannot be qualified (C++ [dcl.meaning]p1). 1412 if (D.getCXXScopeSpec().isSet()) { 1413 Diag(D.getIdentifierLoc(), diag::err_qualified_typedef_declarator) 1414 << D.getCXXScopeSpec().getRange(); 1415 InvalidDecl = true; 1416 // Pretend we didn't see the scope specifier. 1417 DC = 0; 1418 } 1419 1420 // Check that there are no default arguments (C++ only). 1421 if (getLangOptions().CPlusPlus) 1422 CheckExtraCXXDefaultArguments(D); 1423 1424 TypedefDecl *NewTD = ParseTypedefDecl(S, D, R, LastDeclarator); 1425 if (!NewTD) return 0; 1426 1427 // Handle attributes prior to checking for duplicates in MergeVarDecl 1428 ProcessDeclAttributes(NewTD, D); 1429 // Merge the decl with the existing one if appropriate. If the decl is 1430 // in an outer scope, it isn't the same thing. 1431 if (PrevDecl && isDeclInScope(PrevDecl, DC, S)) { 1432 Redeclaration = true; 1433 if (MergeTypeDefDecl(NewTD, PrevDecl)) 1434 InvalidDecl = true; 1435 } 1436 1437 if (S->getFnParent() == 0) { 1438 // C99 6.7.7p2: If a typedef name specifies a variably modified type 1439 // then it shall have block scope. 1440 if (NewTD->getUnderlyingType()->isVariablyModifiedType()) { 1441 if (NewTD->getUnderlyingType()->isVariableArrayType()) 1442 Diag(D.getIdentifierLoc(), diag::err_vla_decl_in_file_scope); 1443 else 1444 Diag(D.getIdentifierLoc(), diag::err_vm_decl_in_file_scope); 1445 1446 InvalidDecl = true; 1447 } 1448 } 1449 return NewTD; 1450} 1451 1452NamedDecl* 1453Sema::ActOnVariableDeclarator(Scope* S, Declarator& D, DeclContext* DC, 1454 QualType R, Decl* LastDeclarator, 1455 Decl* PrevDecl, bool& InvalidDecl, 1456 bool &Redeclaration) { 1457 DeclarationName Name = GetNameForDeclarator(D); 1458 1459 // Check that there are no default arguments (C++ only). 1460 if (getLangOptions().CPlusPlus) 1461 CheckExtraCXXDefaultArguments(D); 1462 1463 if (R.getTypePtr()->isObjCInterfaceType()) { 1464 Diag(D.getIdentifierLoc(), diag::err_statically_allocated_object) 1465 << D.getIdentifier(); 1466 InvalidDecl = true; 1467 } 1468 1469 VarDecl *NewVD; 1470 VarDecl::StorageClass SC; 1471 switch (D.getDeclSpec().getStorageClassSpec()) { 1472 default: assert(0 && "Unknown storage class!"); 1473 case DeclSpec::SCS_unspecified: SC = VarDecl::None; break; 1474 case DeclSpec::SCS_extern: SC = VarDecl::Extern; break; 1475 case DeclSpec::SCS_static: SC = VarDecl::Static; break; 1476 case DeclSpec::SCS_auto: SC = VarDecl::Auto; break; 1477 case DeclSpec::SCS_register: SC = VarDecl::Register; break; 1478 case DeclSpec::SCS_private_extern: SC = VarDecl::PrivateExtern; break; 1479 case DeclSpec::SCS_mutable: 1480 // mutable can only appear on non-static class members, so it's always 1481 // an error here 1482 Diag(D.getIdentifierLoc(), diag::err_mutable_nonmember); 1483 InvalidDecl = true; 1484 SC = VarDecl::None; 1485 break; 1486 } 1487 1488 IdentifierInfo *II = Name.getAsIdentifierInfo(); 1489 if (!II) { 1490 Diag(D.getIdentifierLoc(), diag::err_bad_variable_name) 1491 << Name.getAsString(); 1492 return 0; 1493 } 1494 1495 if (DC->isRecord()) { 1496 // This is a static data member for a C++ class. 1497 NewVD = CXXClassVarDecl::Create(Context, cast<CXXRecordDecl>(DC), 1498 D.getIdentifierLoc(), II, 1499 R); 1500 } else { 1501 bool ThreadSpecified = D.getDeclSpec().isThreadSpecified(); 1502 if (S->getFnParent() == 0) { 1503 // C99 6.9p2: The storage-class specifiers auto and register shall not 1504 // appear in the declaration specifiers in an external declaration. 1505 if (SC == VarDecl::Auto || SC == VarDecl::Register) { 1506 Diag(D.getIdentifierLoc(), diag::err_typecheck_sclass_fscope); 1507 InvalidDecl = true; 1508 } 1509 } 1510 NewVD = VarDecl::Create(Context, DC, D.getIdentifierLoc(), 1511 II, R, SC, 1512 // FIXME: Move to DeclGroup... 1513 D.getDeclSpec().getSourceRange().getBegin()); 1514 NewVD->setThreadSpecified(ThreadSpecified); 1515 } 1516 NewVD->setNextDeclarator(LastDeclarator); 1517 1518 // Handle attributes prior to checking for duplicates in MergeVarDecl 1519 ProcessDeclAttributes(NewVD, D); 1520 1521 // Handle GNU asm-label extension (encoded as an attribute). 1522 if (Expr *E = (Expr*) D.getAsmLabel()) { 1523 // The parser guarantees this is a string. 1524 StringLiteral *SE = cast<StringLiteral>(E); 1525 NewVD->addAttr(new AsmLabelAttr(std::string(SE->getStrData(), 1526 SE->getByteLength()))); 1527 } 1528 1529 // Emit an error if an address space was applied to decl with local storage. 1530 // This includes arrays of objects with address space qualifiers, but not 1531 // automatic variables that point to other address spaces. 1532 // ISO/IEC TR 18037 S5.1.2 1533 if (NewVD->hasLocalStorage() && (NewVD->getType().getAddressSpace() != 0)) { 1534 Diag(D.getIdentifierLoc(), diag::err_as_qualified_auto_decl); 1535 InvalidDecl = true; 1536 } 1537 // Merge the decl with the existing one if appropriate. If the decl is 1538 // in an outer scope, it isn't the same thing. 1539 if (PrevDecl && isDeclInScope(PrevDecl, DC, S)) { 1540 if (isa<FieldDecl>(PrevDecl) && D.getCXXScopeSpec().isSet()) { 1541 // The user tried to define a non-static data member 1542 // out-of-line (C++ [dcl.meaning]p1). 1543 Diag(NewVD->getLocation(), diag::err_nonstatic_member_out_of_line) 1544 << D.getCXXScopeSpec().getRange(); 1545 NewVD->Destroy(Context); 1546 return 0; 1547 } 1548 1549 Redeclaration = true; 1550 if (MergeVarDecl(NewVD, PrevDecl)) 1551 InvalidDecl = true; 1552 1553 if (D.getCXXScopeSpec().isSet()) { 1554 // No previous declaration in the qualifying scope. 1555 Diag(D.getIdentifierLoc(), diag::err_typecheck_no_member) 1556 << Name << D.getCXXScopeSpec().getRange(); 1557 InvalidDecl = true; 1558 } 1559 } 1560 return NewVD; 1561} 1562 1563NamedDecl* 1564Sema::ActOnFunctionDeclarator(Scope* S, Declarator& D, DeclContext* DC, 1565 QualType R, Decl *LastDeclarator, 1566 Decl* PrevDecl, bool IsFunctionDefinition, 1567 bool& InvalidDecl, bool &Redeclaration) { 1568 assert(R.getTypePtr()->isFunctionType()); 1569 1570 DeclarationName Name = GetNameForDeclarator(D); 1571 FunctionDecl::StorageClass SC = FunctionDecl::None; 1572 switch (D.getDeclSpec().getStorageClassSpec()) { 1573 default: assert(0 && "Unknown storage class!"); 1574 case DeclSpec::SCS_auto: 1575 case DeclSpec::SCS_register: 1576 case DeclSpec::SCS_mutable: 1577 Diag(D.getIdentifierLoc(), diag::err_typecheck_sclass_func); 1578 InvalidDecl = true; 1579 break; 1580 case DeclSpec::SCS_unspecified: SC = FunctionDecl::None; break; 1581 case DeclSpec::SCS_extern: SC = FunctionDecl::Extern; break; 1582 case DeclSpec::SCS_static: SC = FunctionDecl::Static; break; 1583 case DeclSpec::SCS_private_extern: SC = FunctionDecl::PrivateExtern;break; 1584 } 1585 1586 bool isInline = D.getDeclSpec().isInlineSpecified(); 1587 // bool isVirtual = D.getDeclSpec().isVirtualSpecified(); 1588 bool isExplicit = D.getDeclSpec().isExplicitSpecified(); 1589 1590 FunctionDecl *NewFD; 1591 if (D.getKind() == Declarator::DK_Constructor) { 1592 // This is a C++ constructor declaration. 1593 assert(DC->isRecord() && 1594 "Constructors can only be declared in a member context"); 1595 1596 InvalidDecl = InvalidDecl || CheckConstructorDeclarator(D, R, SC); 1597 1598 // Create the new declaration 1599 NewFD = CXXConstructorDecl::Create(Context, 1600 cast<CXXRecordDecl>(DC), 1601 D.getIdentifierLoc(), Name, R, 1602 isExplicit, isInline, 1603 /*isImplicitlyDeclared=*/false); 1604 1605 if (InvalidDecl) 1606 NewFD->setInvalidDecl(); 1607 } else if (D.getKind() == Declarator::DK_Destructor) { 1608 // This is a C++ destructor declaration. 1609 if (DC->isRecord()) { 1610 InvalidDecl = InvalidDecl || CheckDestructorDeclarator(D, R, SC); 1611 1612 NewFD = CXXDestructorDecl::Create(Context, 1613 cast<CXXRecordDecl>(DC), 1614 D.getIdentifierLoc(), Name, R, 1615 isInline, 1616 /*isImplicitlyDeclared=*/false); 1617 1618 if (InvalidDecl) 1619 NewFD->setInvalidDecl(); 1620 } else { 1621 Diag(D.getIdentifierLoc(), diag::err_destructor_not_member); 1622 1623 // Create a FunctionDecl to satisfy the function definition parsing 1624 // code path. 1625 NewFD = FunctionDecl::Create(Context, DC, D.getIdentifierLoc(), 1626 Name, R, SC, isInline, 1627 // FIXME: Move to DeclGroup... 1628 D.getDeclSpec().getSourceRange().getBegin()); 1629 InvalidDecl = true; 1630 NewFD->setInvalidDecl(); 1631 } 1632 } else if (D.getKind() == Declarator::DK_Conversion) { 1633 if (!DC->isRecord()) { 1634 Diag(D.getIdentifierLoc(), 1635 diag::err_conv_function_not_member); 1636 return 0; 1637 } else { 1638 InvalidDecl = InvalidDecl || CheckConversionDeclarator(D, R, SC); 1639 1640 NewFD = CXXConversionDecl::Create(Context, cast<CXXRecordDecl>(DC), 1641 D.getIdentifierLoc(), Name, R, 1642 isInline, isExplicit); 1643 1644 if (InvalidDecl) 1645 NewFD->setInvalidDecl(); 1646 } 1647 } else if (DC->isRecord()) { 1648 // This is a C++ method declaration. 1649 NewFD = CXXMethodDecl::Create(Context, cast<CXXRecordDecl>(DC), 1650 D.getIdentifierLoc(), Name, R, 1651 (SC == FunctionDecl::Static), isInline); 1652 } else { 1653 NewFD = FunctionDecl::Create(Context, DC, 1654 D.getIdentifierLoc(), 1655 Name, R, SC, isInline, 1656 // FIXME: Move to DeclGroup... 1657 D.getDeclSpec().getSourceRange().getBegin()); 1658 } 1659 NewFD->setNextDeclarator(LastDeclarator); 1660 1661 // Set the lexical context. If the declarator has a C++ 1662 // scope specifier, the lexical context will be different 1663 // from the semantic context. 1664 NewFD->setLexicalDeclContext(CurContext); 1665 1666 // Handle GNU asm-label extension (encoded as an attribute). 1667 if (Expr *E = (Expr*) D.getAsmLabel()) { 1668 // The parser guarantees this is a string. 1669 StringLiteral *SE = cast<StringLiteral>(E); 1670 NewFD->addAttr(new AsmLabelAttr(std::string(SE->getStrData(), 1671 SE->getByteLength()))); 1672 } 1673 1674 // Copy the parameter declarations from the declarator D to 1675 // the function declaration NewFD, if they are available. 1676 if (D.getNumTypeObjects() > 0) { 1677 DeclaratorChunk::FunctionTypeInfo &FTI = D.getTypeObject(0).Fun; 1678 1679 // Create Decl objects for each parameter, adding them to the 1680 // FunctionDecl. 1681 llvm::SmallVector<ParmVarDecl*, 16> Params; 1682 1683 // Check for C99 6.7.5.3p10 - foo(void) is a non-varargs 1684 // function that takes no arguments, not a function that takes a 1685 // single void argument. 1686 // We let through "const void" here because Sema::GetTypeForDeclarator 1687 // already checks for that case. 1688 if (FTI.NumArgs == 1 && !FTI.isVariadic && FTI.ArgInfo[0].Ident == 0 && 1689 FTI.ArgInfo[0].Param && 1690 ((ParmVarDecl*)FTI.ArgInfo[0].Param)->getType()->isVoidType()) { 1691 // empty arg list, don't push any params. 1692 ParmVarDecl *Param = (ParmVarDecl*)FTI.ArgInfo[0].Param; 1693 1694 // In C++, the empty parameter-type-list must be spelled "void"; a 1695 // typedef of void is not permitted. 1696 if (getLangOptions().CPlusPlus && 1697 Param->getType().getUnqualifiedType() != Context.VoidTy) { 1698 Diag(Param->getLocation(), diag::ext_param_typedef_of_void); 1699 } 1700 } else if (FTI.NumArgs > 0 && FTI.ArgInfo[0].Param != 0) { 1701 for (unsigned i = 0, e = FTI.NumArgs; i != e; ++i) 1702 Params.push_back((ParmVarDecl *)FTI.ArgInfo[i].Param); 1703 } 1704 1705 NewFD->setParams(Context, &Params[0], Params.size()); 1706 } else if (R->getAsTypedefType()) { 1707 // When we're declaring a function with a typedef, as in the 1708 // following example, we'll need to synthesize (unnamed) 1709 // parameters for use in the declaration. 1710 // 1711 // @code 1712 // typedef void fn(int); 1713 // fn f; 1714 // @endcode 1715 const FunctionTypeProto *FT = R->getAsFunctionTypeProto(); 1716 if (!FT) { 1717 // This is a typedef of a function with no prototype, so we 1718 // don't need to do anything. 1719 } else if ((FT->getNumArgs() == 0) || 1720 (FT->getNumArgs() == 1 && !FT->isVariadic() && 1721 FT->getArgType(0)->isVoidType())) { 1722 // This is a zero-argument function. We don't need to do anything. 1723 } else { 1724 // Synthesize a parameter for each argument type. 1725 llvm::SmallVector<ParmVarDecl*, 16> Params; 1726 for (FunctionTypeProto::arg_type_iterator ArgType = FT->arg_type_begin(); 1727 ArgType != FT->arg_type_end(); ++ArgType) { 1728 ParmVarDecl *Param = ParmVarDecl::Create(Context, DC, 1729 SourceLocation(), 0, 1730 *ArgType, VarDecl::None, 1731 0); 1732 Param->setImplicit(); 1733 Params.push_back(Param); 1734 } 1735 1736 NewFD->setParams(Context, &Params[0], Params.size()); 1737 } 1738 } 1739 1740 if (CXXConstructorDecl *Constructor = dyn_cast<CXXConstructorDecl>(NewFD)) 1741 InvalidDecl = InvalidDecl || CheckConstructor(Constructor); 1742 else if (isa<CXXDestructorDecl>(NewFD)) { 1743 CXXRecordDecl *Record = cast<CXXRecordDecl>(NewFD->getParent()); 1744 Record->setUserDeclaredDestructor(true); 1745 // C++ [class]p4: A POD-struct is an aggregate class that has [...] no 1746 // user-defined destructor. 1747 Record->setPOD(false); 1748 } else if (CXXConversionDecl *Conversion = 1749 dyn_cast<CXXConversionDecl>(NewFD)) 1750 ActOnConversionDeclarator(Conversion); 1751 1752 // Extra checking for C++ overloaded operators (C++ [over.oper]). 1753 if (NewFD->isOverloadedOperator() && 1754 CheckOverloadedOperatorDeclaration(NewFD)) 1755 NewFD->setInvalidDecl(); 1756 1757 // Merge the decl with the existing one if appropriate. Since C functions 1758 // are in a flat namespace, make sure we consider decls in outer scopes. 1759 bool OverloadableAttrRequired = false; 1760 if (PrevDecl && 1761 (!getLangOptions().CPlusPlus||isDeclInScope(PrevDecl, DC, S))) { 1762 // Determine whether NewFD is an overload of PrevDecl or 1763 // a declaration that requires merging. If it's an overload, 1764 // there's no more work to do here; we'll just add the new 1765 // function to the scope. 1766 OverloadedFunctionDecl::function_iterator MatchedDecl; 1767 1768 if (!getLangOptions().CPlusPlus && 1769 AllowOverloadingOfFunction(PrevDecl, Context)) 1770 OverloadableAttrRequired = true; 1771 1772 if (!AllowOverloadingOfFunction(PrevDecl, Context) || 1773 !IsOverload(NewFD, PrevDecl, MatchedDecl)) { 1774 Redeclaration = true; 1775 Decl *OldDecl = PrevDecl; 1776 1777 // If PrevDecl was an overloaded function, extract the 1778 // FunctionDecl that matched. 1779 if (isa<OverloadedFunctionDecl>(PrevDecl)) 1780 OldDecl = *MatchedDecl; 1781 1782 // NewFD and PrevDecl represent declarations that need to be 1783 // merged. 1784 if (MergeFunctionDecl(NewFD, OldDecl)) 1785 InvalidDecl = true; 1786 1787 if (!InvalidDecl) { 1788 NewFD->setPreviousDeclaration(cast<FunctionDecl>(OldDecl)); 1789 1790 // An out-of-line member function declaration must also be a 1791 // definition (C++ [dcl.meaning]p1). 1792 if (!IsFunctionDefinition && D.getCXXScopeSpec().isSet() && 1793 !InvalidDecl) { 1794 Diag(NewFD->getLocation(), diag::err_out_of_line_declaration) 1795 << D.getCXXScopeSpec().getRange(); 1796 NewFD->setInvalidDecl(); 1797 } 1798 } 1799 } 1800 } 1801 1802 if (D.getCXXScopeSpec().isSet() && 1803 (!PrevDecl || !Redeclaration)) { 1804 // The user tried to provide an out-of-line definition for a 1805 // function that is a member of a class or namespace, but there 1806 // was no such member function declared (C++ [class.mfct]p2, 1807 // C++ [namespace.memdef]p2). For example: 1808 // 1809 // class X { 1810 // void f() const; 1811 // }; 1812 // 1813 // void X::f() { } // ill-formed 1814 // 1815 // Complain about this problem, and attempt to suggest close 1816 // matches (e.g., those that differ only in cv-qualifiers and 1817 // whether the parameter types are references). 1818 Diag(D.getIdentifierLoc(), diag::err_member_def_does_not_match) 1819 << cast<NamedDecl>(DC) << D.getCXXScopeSpec().getRange(); 1820 InvalidDecl = true; 1821 1822 LookupResult Prev = LookupQualifiedName(DC, Name, LookupOrdinaryName, 1823 true); 1824 assert(!Prev.isAmbiguous() && 1825 "Cannot have an ambiguity in previous-declaration lookup"); 1826 for (LookupResult::iterator Func = Prev.begin(), FuncEnd = Prev.end(); 1827 Func != FuncEnd; ++Func) { 1828 if (isa<FunctionDecl>(*Func) && 1829 isNearlyMatchingFunction(Context, cast<FunctionDecl>(*Func), NewFD)) 1830 Diag((*Func)->getLocation(), diag::note_member_def_close_match); 1831 } 1832 1833 PrevDecl = 0; 1834 } 1835 1836 // Handle attributes. We need to have merged decls when handling attributes 1837 // (for example to check for conflicts, etc). 1838 ProcessDeclAttributes(NewFD, D); 1839 AddKnownFunctionAttributes(NewFD); 1840 1841 if (OverloadableAttrRequired && !NewFD->getAttr<OverloadableAttr>()) { 1842 // If a function name is overloadable in C, then every function 1843 // with that name must be marked "overloadable". 1844 Diag(NewFD->getLocation(), diag::err_attribute_overloadable_missing) 1845 << Redeclaration << NewFD; 1846 if (PrevDecl) 1847 Diag(PrevDecl->getLocation(), 1848 diag::note_attribute_overloadable_prev_overload); 1849 NewFD->addAttr(new OverloadableAttr); 1850 } 1851 1852 if (getLangOptions().CPlusPlus) { 1853 // In C++, check default arguments now that we have merged decls. Unless 1854 // the lexical context is the class, because in this case this is done 1855 // during delayed parsing anyway. 1856 if (!CurContext->isRecord()) 1857 CheckCXXDefaultArguments(NewFD); 1858 1859 // An out-of-line member function declaration must also be a 1860 // definition (C++ [dcl.meaning]p1). 1861 if (!IsFunctionDefinition && D.getCXXScopeSpec().isSet() && !InvalidDecl) { 1862 Diag(NewFD->getLocation(), diag::err_out_of_line_declaration) 1863 << D.getCXXScopeSpec().getRange(); 1864 InvalidDecl = true; 1865 } 1866 } 1867 return NewFD; 1868} 1869 1870void Sema::InitializerElementNotConstant(const Expr *Init) { 1871 Diag(Init->getExprLoc(), diag::err_init_element_not_constant) 1872 << Init->getSourceRange(); 1873} 1874 1875bool Sema::CheckAddressConstantExpressionLValue(const Expr* Init) { 1876 switch (Init->getStmtClass()) { 1877 default: 1878 InitializerElementNotConstant(Init); 1879 return true; 1880 case Expr::ParenExprClass: { 1881 const ParenExpr* PE = cast<ParenExpr>(Init); 1882 return CheckAddressConstantExpressionLValue(PE->getSubExpr()); 1883 } 1884 case Expr::CompoundLiteralExprClass: 1885 return cast<CompoundLiteralExpr>(Init)->isFileScope(); 1886 case Expr::DeclRefExprClass: 1887 case Expr::QualifiedDeclRefExprClass: { 1888 const Decl *D = cast<DeclRefExpr>(Init)->getDecl(); 1889 if (const VarDecl *VD = dyn_cast<VarDecl>(D)) { 1890 if (VD->hasGlobalStorage()) 1891 return false; 1892 InitializerElementNotConstant(Init); 1893 return true; 1894 } 1895 if (isa<FunctionDecl>(D)) 1896 return false; 1897 InitializerElementNotConstant(Init); 1898 return true; 1899 } 1900 case Expr::MemberExprClass: { 1901 const MemberExpr *M = cast<MemberExpr>(Init); 1902 if (M->isArrow()) 1903 return CheckAddressConstantExpression(M->getBase()); 1904 return CheckAddressConstantExpressionLValue(M->getBase()); 1905 } 1906 case Expr::ArraySubscriptExprClass: { 1907 // FIXME: Should we pedwarn for "x[0+0]" (where x is a pointer)? 1908 const ArraySubscriptExpr *ASE = cast<ArraySubscriptExpr>(Init); 1909 return CheckAddressConstantExpression(ASE->getBase()) || 1910 CheckArithmeticConstantExpression(ASE->getIdx()); 1911 } 1912 case Expr::StringLiteralClass: 1913 case Expr::PredefinedExprClass: 1914 return false; 1915 case Expr::UnaryOperatorClass: { 1916 const UnaryOperator *Exp = cast<UnaryOperator>(Init); 1917 1918 // C99 6.6p9 1919 if (Exp->getOpcode() == UnaryOperator::Deref) 1920 return CheckAddressConstantExpression(Exp->getSubExpr()); 1921 1922 InitializerElementNotConstant(Init); 1923 return true; 1924 } 1925 } 1926} 1927 1928bool Sema::CheckAddressConstantExpression(const Expr* Init) { 1929 switch (Init->getStmtClass()) { 1930 default: 1931 InitializerElementNotConstant(Init); 1932 return true; 1933 case Expr::ParenExprClass: 1934 return CheckAddressConstantExpression(cast<ParenExpr>(Init)->getSubExpr()); 1935 case Expr::StringLiteralClass: 1936 case Expr::ObjCStringLiteralClass: 1937 return false; 1938 case Expr::CallExprClass: 1939 case Expr::CXXOperatorCallExprClass: 1940 // __builtin___CFStringMakeConstantString is a valid constant l-value. 1941 if (cast<CallExpr>(Init)->isBuiltinCall(Context) == 1942 Builtin::BI__builtin___CFStringMakeConstantString) 1943 return false; 1944 1945 InitializerElementNotConstant(Init); 1946 return true; 1947 1948 case Expr::UnaryOperatorClass: { 1949 const UnaryOperator *Exp = cast<UnaryOperator>(Init); 1950 1951 // C99 6.6p9 1952 if (Exp->getOpcode() == UnaryOperator::AddrOf) 1953 return CheckAddressConstantExpressionLValue(Exp->getSubExpr()); 1954 1955 if (Exp->getOpcode() == UnaryOperator::Extension) 1956 return CheckAddressConstantExpression(Exp->getSubExpr()); 1957 1958 InitializerElementNotConstant(Init); 1959 return true; 1960 } 1961 case Expr::BinaryOperatorClass: { 1962 // FIXME: Should we pedwarn for expressions like "a + 1 + 2"? 1963 const BinaryOperator *Exp = cast<BinaryOperator>(Init); 1964 1965 Expr *PExp = Exp->getLHS(); 1966 Expr *IExp = Exp->getRHS(); 1967 if (IExp->getType()->isPointerType()) 1968 std::swap(PExp, IExp); 1969 1970 // FIXME: Should we pedwarn if IExp isn't an integer constant expression? 1971 return CheckAddressConstantExpression(PExp) || 1972 CheckArithmeticConstantExpression(IExp); 1973 } 1974 case Expr::ImplicitCastExprClass: 1975 case Expr::CStyleCastExprClass: { 1976 const Expr* SubExpr = cast<CastExpr>(Init)->getSubExpr(); 1977 if (Init->getStmtClass() == Expr::ImplicitCastExprClass) { 1978 // Check for implicit promotion 1979 if (SubExpr->getType()->isFunctionType() || 1980 SubExpr->getType()->isArrayType()) 1981 return CheckAddressConstantExpressionLValue(SubExpr); 1982 } 1983 1984 // Check for pointer->pointer cast 1985 if (SubExpr->getType()->isPointerType()) 1986 return CheckAddressConstantExpression(SubExpr); 1987 1988 if (SubExpr->getType()->isIntegralType()) { 1989 // Check for the special-case of a pointer->int->pointer cast; 1990 // this isn't standard, but some code requires it. See 1991 // PR2720 for an example. 1992 if (const CastExpr* SubCast = dyn_cast<CastExpr>(SubExpr)) { 1993 if (SubCast->getSubExpr()->getType()->isPointerType()) { 1994 unsigned IntWidth = Context.getIntWidth(SubCast->getType()); 1995 unsigned PointerWidth = Context.getTypeSize(Context.VoidPtrTy); 1996 if (IntWidth >= PointerWidth) { 1997 return CheckAddressConstantExpression(SubCast->getSubExpr()); 1998 } 1999 } 2000 } 2001 } 2002 if (SubExpr->getType()->isArithmeticType()) { 2003 return CheckArithmeticConstantExpression(SubExpr); 2004 } 2005 2006 InitializerElementNotConstant(Init); 2007 return true; 2008 } 2009 case Expr::ConditionalOperatorClass: { 2010 // FIXME: Should we pedwarn here? 2011 const ConditionalOperator *Exp = cast<ConditionalOperator>(Init); 2012 if (!Exp->getCond()->getType()->isArithmeticType()) { 2013 InitializerElementNotConstant(Init); 2014 return true; 2015 } 2016 if (CheckArithmeticConstantExpression(Exp->getCond())) 2017 return true; 2018 if (Exp->getLHS() && 2019 CheckAddressConstantExpression(Exp->getLHS())) 2020 return true; 2021 return CheckAddressConstantExpression(Exp->getRHS()); 2022 } 2023 case Expr::AddrLabelExprClass: 2024 return false; 2025 } 2026} 2027 2028static const Expr* FindExpressionBaseAddress(const Expr* E); 2029 2030static const Expr* FindExpressionBaseAddressLValue(const Expr* E) { 2031 switch (E->getStmtClass()) { 2032 default: 2033 return E; 2034 case Expr::ParenExprClass: { 2035 const ParenExpr* PE = cast<ParenExpr>(E); 2036 return FindExpressionBaseAddressLValue(PE->getSubExpr()); 2037 } 2038 case Expr::MemberExprClass: { 2039 const MemberExpr *M = cast<MemberExpr>(E); 2040 if (M->isArrow()) 2041 return FindExpressionBaseAddress(M->getBase()); 2042 return FindExpressionBaseAddressLValue(M->getBase()); 2043 } 2044 case Expr::ArraySubscriptExprClass: { 2045 const ArraySubscriptExpr *ASE = cast<ArraySubscriptExpr>(E); 2046 return FindExpressionBaseAddress(ASE->getBase()); 2047 } 2048 case Expr::UnaryOperatorClass: { 2049 const UnaryOperator *Exp = cast<UnaryOperator>(E); 2050 2051 if (Exp->getOpcode() == UnaryOperator::Deref) 2052 return FindExpressionBaseAddress(Exp->getSubExpr()); 2053 2054 return E; 2055 } 2056 } 2057} 2058 2059static const Expr* FindExpressionBaseAddress(const Expr* E) { 2060 switch (E->getStmtClass()) { 2061 default: 2062 return E; 2063 case Expr::ParenExprClass: { 2064 const ParenExpr* PE = cast<ParenExpr>(E); 2065 return FindExpressionBaseAddress(PE->getSubExpr()); 2066 } 2067 case Expr::UnaryOperatorClass: { 2068 const UnaryOperator *Exp = cast<UnaryOperator>(E); 2069 2070 // C99 6.6p9 2071 if (Exp->getOpcode() == UnaryOperator::AddrOf) 2072 return FindExpressionBaseAddressLValue(Exp->getSubExpr()); 2073 2074 if (Exp->getOpcode() == UnaryOperator::Extension) 2075 return FindExpressionBaseAddress(Exp->getSubExpr()); 2076 2077 return E; 2078 } 2079 case Expr::BinaryOperatorClass: { 2080 const BinaryOperator *Exp = cast<BinaryOperator>(E); 2081 2082 Expr *PExp = Exp->getLHS(); 2083 Expr *IExp = Exp->getRHS(); 2084 if (IExp->getType()->isPointerType()) 2085 std::swap(PExp, IExp); 2086 2087 return FindExpressionBaseAddress(PExp); 2088 } 2089 case Expr::ImplicitCastExprClass: { 2090 const Expr* SubExpr = cast<ImplicitCastExpr>(E)->getSubExpr(); 2091 2092 // Check for implicit promotion 2093 if (SubExpr->getType()->isFunctionType() || 2094 SubExpr->getType()->isArrayType()) 2095 return FindExpressionBaseAddressLValue(SubExpr); 2096 2097 // Check for pointer->pointer cast 2098 if (SubExpr->getType()->isPointerType()) 2099 return FindExpressionBaseAddress(SubExpr); 2100 2101 // We assume that we have an arithmetic expression here; 2102 // if we don't, we'll figure it out later 2103 return 0; 2104 } 2105 case Expr::CStyleCastExprClass: { 2106 const Expr* SubExpr = cast<CastExpr>(E)->getSubExpr(); 2107 2108 // Check for pointer->pointer cast 2109 if (SubExpr->getType()->isPointerType()) 2110 return FindExpressionBaseAddress(SubExpr); 2111 2112 // We assume that we have an arithmetic expression here; 2113 // if we don't, we'll figure it out later 2114 return 0; 2115 } 2116 } 2117} 2118 2119bool Sema::CheckArithmeticConstantExpression(const Expr* Init) { 2120 switch (Init->getStmtClass()) { 2121 default: 2122 InitializerElementNotConstant(Init); 2123 return true; 2124 case Expr::ParenExprClass: { 2125 const ParenExpr* PE = cast<ParenExpr>(Init); 2126 return CheckArithmeticConstantExpression(PE->getSubExpr()); 2127 } 2128 case Expr::FloatingLiteralClass: 2129 case Expr::IntegerLiteralClass: 2130 case Expr::CharacterLiteralClass: 2131 case Expr::ImaginaryLiteralClass: 2132 case Expr::TypesCompatibleExprClass: 2133 case Expr::CXXBoolLiteralExprClass: 2134 return false; 2135 case Expr::CallExprClass: 2136 case Expr::CXXOperatorCallExprClass: { 2137 const CallExpr *CE = cast<CallExpr>(Init); 2138 2139 // Allow any constant foldable calls to builtins. 2140 if (CE->isBuiltinCall(Context) && CE->isEvaluatable(Context)) 2141 return false; 2142 2143 InitializerElementNotConstant(Init); 2144 return true; 2145 } 2146 case Expr::DeclRefExprClass: 2147 case Expr::QualifiedDeclRefExprClass: { 2148 const Decl *D = cast<DeclRefExpr>(Init)->getDecl(); 2149 if (isa<EnumConstantDecl>(D)) 2150 return false; 2151 InitializerElementNotConstant(Init); 2152 return true; 2153 } 2154 case Expr::CompoundLiteralExprClass: 2155 // Allow "(vector type){2,4}"; normal C constraints don't allow this, 2156 // but vectors are allowed to be magic. 2157 if (Init->getType()->isVectorType()) 2158 return false; 2159 InitializerElementNotConstant(Init); 2160 return true; 2161 case Expr::UnaryOperatorClass: { 2162 const UnaryOperator *Exp = cast<UnaryOperator>(Init); 2163 2164 switch (Exp->getOpcode()) { 2165 // Address, indirect, pre/post inc/dec, etc are not valid constant exprs. 2166 // See C99 6.6p3. 2167 default: 2168 InitializerElementNotConstant(Init); 2169 return true; 2170 case UnaryOperator::OffsetOf: 2171 if (Exp->getSubExpr()->getType()->isConstantSizeType()) 2172 return false; 2173 InitializerElementNotConstant(Init); 2174 return true; 2175 case UnaryOperator::Extension: 2176 case UnaryOperator::LNot: 2177 case UnaryOperator::Plus: 2178 case UnaryOperator::Minus: 2179 case UnaryOperator::Not: 2180 return CheckArithmeticConstantExpression(Exp->getSubExpr()); 2181 } 2182 } 2183 case Expr::SizeOfAlignOfExprClass: { 2184 const SizeOfAlignOfExpr *Exp = cast<SizeOfAlignOfExpr>(Init); 2185 // Special check for void types, which are allowed as an extension 2186 if (Exp->getTypeOfArgument()->isVoidType()) 2187 return false; 2188 // alignof always evaluates to a constant. 2189 // FIXME: is sizeof(int[3.0]) a constant expression? 2190 if (Exp->isSizeOf() && !Exp->getTypeOfArgument()->isConstantSizeType()) { 2191 InitializerElementNotConstant(Init); 2192 return true; 2193 } 2194 return false; 2195 } 2196 case Expr::BinaryOperatorClass: { 2197 const BinaryOperator *Exp = cast<BinaryOperator>(Init); 2198 2199 if (Exp->getLHS()->getType()->isArithmeticType() && 2200 Exp->getRHS()->getType()->isArithmeticType()) { 2201 return CheckArithmeticConstantExpression(Exp->getLHS()) || 2202 CheckArithmeticConstantExpression(Exp->getRHS()); 2203 } 2204 2205 if (Exp->getLHS()->getType()->isPointerType() && 2206 Exp->getRHS()->getType()->isPointerType()) { 2207 const Expr* LHSBase = FindExpressionBaseAddress(Exp->getLHS()); 2208 const Expr* RHSBase = FindExpressionBaseAddress(Exp->getRHS()); 2209 2210 // Only allow a null (constant integer) base; we could 2211 // allow some additional cases if necessary, but this 2212 // is sufficient to cover offsetof-like constructs. 2213 if (!LHSBase && !RHSBase) { 2214 return CheckAddressConstantExpression(Exp->getLHS()) || 2215 CheckAddressConstantExpression(Exp->getRHS()); 2216 } 2217 } 2218 2219 InitializerElementNotConstant(Init); 2220 return true; 2221 } 2222 case Expr::ImplicitCastExprClass: 2223 case Expr::CStyleCastExprClass: { 2224 const CastExpr *CE = cast<CastExpr>(Init); 2225 const Expr *SubExpr = CE->getSubExpr(); 2226 2227 if (SubExpr->getType()->isArithmeticType()) 2228 return CheckArithmeticConstantExpression(SubExpr); 2229 2230 if (SubExpr->getType()->isPointerType()) { 2231 const Expr* Base = FindExpressionBaseAddress(SubExpr); 2232 if (Base) { 2233 // the cast is only valid if done to a wide enough type 2234 if (Context.getTypeSize(CE->getType()) >= 2235 Context.getTypeSize(SubExpr->getType())) 2236 return false; 2237 } else { 2238 // If the pointer has a null base, this is an offsetof-like construct 2239 return CheckAddressConstantExpression(SubExpr); 2240 } 2241 } 2242 2243 InitializerElementNotConstant(Init); 2244 return true; 2245 } 2246 case Expr::ConditionalOperatorClass: { 2247 const ConditionalOperator *Exp = cast<ConditionalOperator>(Init); 2248 2249 // If GNU extensions are disabled, we require all operands to be arithmetic 2250 // constant expressions. 2251 if (getLangOptions().NoExtensions) { 2252 return CheckArithmeticConstantExpression(Exp->getCond()) || 2253 (Exp->getLHS() && CheckArithmeticConstantExpression(Exp->getLHS())) || 2254 CheckArithmeticConstantExpression(Exp->getRHS()); 2255 } 2256 2257 // Otherwise, we have to emulate some of the behavior of fold here. 2258 // Basically GCC treats things like "4 ? 1 : somefunc()" as a constant 2259 // because it can constant fold things away. To retain compatibility with 2260 // GCC code, we see if we can fold the condition to a constant (which we 2261 // should always be able to do in theory). If so, we only require the 2262 // specified arm of the conditional to be a constant. This is a horrible 2263 // hack, but is require by real world code that uses __builtin_constant_p. 2264 Expr::EvalResult EvalResult; 2265 if (!Exp->getCond()->Evaluate(EvalResult, Context) || 2266 EvalResult.HasSideEffects) { 2267 // If Evaluate couldn't fold it, CheckArithmeticConstantExpression 2268 // won't be able to either. Use it to emit the diagnostic though. 2269 bool Res = CheckArithmeticConstantExpression(Exp->getCond()); 2270 assert(Res && "Evaluate couldn't evaluate this constant?"); 2271 return Res; 2272 } 2273 2274 // Verify that the side following the condition is also a constant. 2275 const Expr *TrueSide = Exp->getLHS(), *FalseSide = Exp->getRHS(); 2276 if (EvalResult.Val.getInt() == 0) 2277 std::swap(TrueSide, FalseSide); 2278 2279 if (TrueSide && CheckArithmeticConstantExpression(TrueSide)) 2280 return true; 2281 2282 // Okay, the evaluated side evaluates to a constant, so we accept this. 2283 // Check to see if the other side is obviously not a constant. If so, 2284 // emit a warning that this is a GNU extension. 2285 if (FalseSide && !FalseSide->isEvaluatable(Context)) 2286 Diag(Init->getExprLoc(), 2287 diag::ext_typecheck_expression_not_constant_but_accepted) 2288 << FalseSide->getSourceRange(); 2289 return false; 2290 } 2291 } 2292} 2293 2294bool Sema::CheckForConstantInitializer(Expr *Init, QualType DclT) { 2295 if (DesignatedInitExpr *DIE = dyn_cast<DesignatedInitExpr>(Init)) 2296 Init = DIE->getInit(); 2297 2298 Init = Init->IgnoreParens(); 2299 2300 if (Init->isEvaluatable(Context)) 2301 return false; 2302 2303 // Look through CXXDefaultArgExprs; they have no meaning in this context. 2304 if (CXXDefaultArgExpr* DAE = dyn_cast<CXXDefaultArgExpr>(Init)) 2305 return CheckForConstantInitializer(DAE->getExpr(), DclT); 2306 2307 if (CompoundLiteralExpr *e = dyn_cast<CompoundLiteralExpr>(Init)) 2308 return CheckForConstantInitializer(e->getInitializer(), DclT); 2309 2310 if (isa<ImplicitValueInitExpr>(Init)) { 2311 // FIXME: In C++, check for non-POD types. 2312 return false; 2313 } 2314 2315 if (InitListExpr *Exp = dyn_cast<InitListExpr>(Init)) { 2316 unsigned numInits = Exp->getNumInits(); 2317 for (unsigned i = 0; i < numInits; i++) { 2318 // FIXME: Need to get the type of the declaration for C++, 2319 // because it could be a reference? 2320 2321 if (CheckForConstantInitializer(Exp->getInit(i), 2322 Exp->getInit(i)->getType())) 2323 return true; 2324 } 2325 return false; 2326 } 2327 2328 // FIXME: We can probably remove some of this code below, now that 2329 // Expr::Evaluate is doing the heavy lifting for scalars. 2330 2331 if (Init->isNullPointerConstant(Context)) 2332 return false; 2333 if (Init->getType()->isArithmeticType()) { 2334 QualType InitTy = Context.getCanonicalType(Init->getType()) 2335 .getUnqualifiedType(); 2336 if (InitTy == Context.BoolTy) { 2337 // Special handling for pointers implicitly cast to bool; 2338 // (e.g. "_Bool rr = &rr;"). This is only legal at the top level. 2339 if (ImplicitCastExpr* ICE = dyn_cast<ImplicitCastExpr>(Init)) { 2340 Expr* SubE = ICE->getSubExpr(); 2341 if (SubE->getType()->isPointerType() || 2342 SubE->getType()->isArrayType() || 2343 SubE->getType()->isFunctionType()) { 2344 return CheckAddressConstantExpression(Init); 2345 } 2346 } 2347 } else if (InitTy->isIntegralType()) { 2348 Expr* SubE = 0; 2349 if (CastExpr* CE = dyn_cast<CastExpr>(Init)) 2350 SubE = CE->getSubExpr(); 2351 // Special check for pointer cast to int; we allow as an extension 2352 // an address constant cast to an integer if the integer 2353 // is of an appropriate width (this sort of code is apparently used 2354 // in some places). 2355 // FIXME: Add pedwarn? 2356 // FIXME: Don't allow bitfields here! Need the FieldDecl for that. 2357 if (SubE && (SubE->getType()->isPointerType() || 2358 SubE->getType()->isArrayType() || 2359 SubE->getType()->isFunctionType())) { 2360 unsigned IntWidth = Context.getTypeSize(Init->getType()); 2361 unsigned PointerWidth = Context.getTypeSize(Context.VoidPtrTy); 2362 if (IntWidth >= PointerWidth) 2363 return CheckAddressConstantExpression(Init); 2364 } 2365 } 2366 2367 return CheckArithmeticConstantExpression(Init); 2368 } 2369 2370 if (Init->getType()->isPointerType()) 2371 return CheckAddressConstantExpression(Init); 2372 2373 // An array type at the top level that isn't an init-list must 2374 // be a string literal 2375 if (Init->getType()->isArrayType()) 2376 return false; 2377 2378 if (Init->getType()->isFunctionType()) 2379 return false; 2380 2381 // Allow block exprs at top level. 2382 if (Init->getType()->isBlockPointerType()) 2383 return false; 2384 2385 // GCC cast to union extension 2386 // note: the validity of the cast expr is checked by CheckCastTypes() 2387 if (CastExpr *C = dyn_cast<CastExpr>(Init)) { 2388 QualType T = C->getType(); 2389 return T->isUnionType() && CheckForConstantInitializer(C->getSubExpr(), T); 2390 } 2391 2392 InitializerElementNotConstant(Init); 2393 return true; 2394} 2395 2396void Sema::AddInitializerToDecl(DeclTy *dcl, ExprArg init) { 2397 AddInitializerToDecl(dcl, move(init), /*DirectInit=*/false); 2398} 2399 2400/// AddInitializerToDecl - Adds the initializer Init to the 2401/// declaration dcl. If DirectInit is true, this is C++ direct 2402/// initialization rather than copy initialization. 2403void Sema::AddInitializerToDecl(DeclTy *dcl, ExprArg init, bool DirectInit) { 2404 Decl *RealDecl = static_cast<Decl *>(dcl); 2405 Expr *Init = static_cast<Expr *>(init.release()); 2406 assert(Init && "missing initializer"); 2407 2408 // If there is no declaration, there was an error parsing it. Just ignore 2409 // the initializer. 2410 if (RealDecl == 0) { 2411 Init->Destroy(Context); 2412 return; 2413 } 2414 2415 VarDecl *VDecl = dyn_cast<VarDecl>(RealDecl); 2416 if (!VDecl) { 2417 Diag(RealDecl->getLocation(), diag::err_illegal_initializer); 2418 RealDecl->setInvalidDecl(); 2419 return; 2420 } 2421 // Get the decls type and save a reference for later, since 2422 // CheckInitializerTypes may change it. 2423 QualType DclT = VDecl->getType(), SavT = DclT; 2424 if (VDecl->isBlockVarDecl()) { 2425 VarDecl::StorageClass SC = VDecl->getStorageClass(); 2426 if (SC == VarDecl::Extern) { // C99 6.7.8p5 2427 Diag(VDecl->getLocation(), diag::err_block_extern_cant_init); 2428 VDecl->setInvalidDecl(); 2429 } else if (!VDecl->isInvalidDecl()) { 2430 if (CheckInitializerTypes(Init, DclT, VDecl->getLocation(), 2431 VDecl->getDeclName(), DirectInit)) 2432 VDecl->setInvalidDecl(); 2433 2434 // C++ 3.6.2p2, allow dynamic initialization of static initializers. 2435 if (!getLangOptions().CPlusPlus) { 2436 if (SC == VarDecl::Static) // C99 6.7.8p4. 2437 CheckForConstantInitializer(Init, DclT); 2438 } 2439 } 2440 } else if (VDecl->isFileVarDecl()) { 2441 if (VDecl->getStorageClass() == VarDecl::Extern) 2442 Diag(VDecl->getLocation(), diag::warn_extern_init); 2443 if (!VDecl->isInvalidDecl()) 2444 if (CheckInitializerTypes(Init, DclT, VDecl->getLocation(), 2445 VDecl->getDeclName(), DirectInit)) 2446 VDecl->setInvalidDecl(); 2447 2448 // C++ 3.6.2p2, allow dynamic initialization of static initializers. 2449 if (!getLangOptions().CPlusPlus) { 2450 // C99 6.7.8p4. All file scoped initializers need to be constant. 2451 CheckForConstantInitializer(Init, DclT); 2452 } 2453 } 2454 // If the type changed, it means we had an incomplete type that was 2455 // completed by the initializer. For example: 2456 // int ary[] = { 1, 3, 5 }; 2457 // "ary" transitions from a VariableArrayType to a ConstantArrayType. 2458 if (!VDecl->isInvalidDecl() && (DclT != SavT)) { 2459 VDecl->setType(DclT); 2460 Init->setType(DclT); 2461 } 2462 2463 // Attach the initializer to the decl. 2464 VDecl->setInit(Init); 2465 return; 2466} 2467 2468void Sema::ActOnUninitializedDecl(DeclTy *dcl) { 2469 Decl *RealDecl = static_cast<Decl *>(dcl); 2470 2471 // If there is no declaration, there was an error parsing it. Just ignore it. 2472 if (RealDecl == 0) 2473 return; 2474 2475 if (VarDecl *Var = dyn_cast<VarDecl>(RealDecl)) { 2476 QualType Type = Var->getType(); 2477 // C++ [dcl.init.ref]p3: 2478 // The initializer can be omitted for a reference only in a 2479 // parameter declaration (8.3.5), in the declaration of a 2480 // function return type, in the declaration of a class member 2481 // within its class declaration (9.2), and where the extern 2482 // specifier is explicitly used. 2483 if (Type->isReferenceType() && 2484 Var->getStorageClass() != VarDecl::Extern && 2485 Var->getStorageClass() != VarDecl::PrivateExtern) { 2486 Diag(Var->getLocation(), diag::err_reference_var_requires_init) 2487 << Var->getDeclName() 2488 << SourceRange(Var->getLocation(), Var->getLocation()); 2489 Var->setInvalidDecl(); 2490 return; 2491 } 2492 2493 // C++ [dcl.init]p9: 2494 // 2495 // If no initializer is specified for an object, and the object 2496 // is of (possibly cv-qualified) non-POD class type (or array 2497 // thereof), the object shall be default-initialized; if the 2498 // object is of const-qualified type, the underlying class type 2499 // shall have a user-declared default constructor. 2500 if (getLangOptions().CPlusPlus) { 2501 QualType InitType = Type; 2502 if (const ArrayType *Array = Context.getAsArrayType(Type)) 2503 InitType = Array->getElementType(); 2504 if (Var->getStorageClass() != VarDecl::Extern && 2505 Var->getStorageClass() != VarDecl::PrivateExtern && 2506 InitType->isRecordType()) { 2507 const CXXConstructorDecl *Constructor 2508 = PerformInitializationByConstructor(InitType, 0, 0, 2509 Var->getLocation(), 2510 SourceRange(Var->getLocation(), 2511 Var->getLocation()), 2512 Var->getDeclName(), 2513 IK_Default); 2514 if (!Constructor) 2515 Var->setInvalidDecl(); 2516 } 2517 } 2518 2519#if 0 2520 // FIXME: Temporarily disabled because we are not properly parsing 2521 // linkage specifications on declarations, e.g., 2522 // 2523 // extern "C" const CGPoint CGPointerZero; 2524 // 2525 // C++ [dcl.init]p9: 2526 // 2527 // If no initializer is specified for an object, and the 2528 // object is of (possibly cv-qualified) non-POD class type (or 2529 // array thereof), the object shall be default-initialized; if 2530 // the object is of const-qualified type, the underlying class 2531 // type shall have a user-declared default 2532 // constructor. Otherwise, if no initializer is specified for 2533 // an object, the object and its subobjects, if any, have an 2534 // indeterminate initial value; if the object or any of its 2535 // subobjects are of const-qualified type, the program is 2536 // ill-formed. 2537 // 2538 // This isn't technically an error in C, so we don't diagnose it. 2539 // 2540 // FIXME: Actually perform the POD/user-defined default 2541 // constructor check. 2542 if (getLangOptions().CPlusPlus && 2543 Context.getCanonicalType(Type).isConstQualified() && 2544 Var->getStorageClass() != VarDecl::Extern) 2545 Diag(Var->getLocation(), diag::err_const_var_requires_init) 2546 << Var->getName() 2547 << SourceRange(Var->getLocation(), Var->getLocation()); 2548#endif 2549 } 2550} 2551 2552/// The declarators are chained together backwards, reverse the list. 2553Sema::DeclTy *Sema::FinalizeDeclaratorGroup(Scope *S, DeclTy *group) { 2554 // Often we have single declarators, handle them quickly. 2555 Decl *GroupDecl = static_cast<Decl*>(group); 2556 if (GroupDecl == 0) 2557 return 0; 2558 2559 Decl *Group = dyn_cast<Decl>(GroupDecl); 2560 Decl *NewGroup = 0; 2561 if (Group->getNextDeclarator() == 0) 2562 NewGroup = Group; 2563 else { // reverse the list. 2564 while (Group) { 2565 Decl *Next = Group->getNextDeclarator(); 2566 Group->setNextDeclarator(NewGroup); 2567 NewGroup = Group; 2568 Group = Next; 2569 } 2570 } 2571 // Perform semantic analysis that depends on having fully processed both 2572 // the declarator and initializer. 2573 for (Decl *ID = NewGroup; ID; ID = ID->getNextDeclarator()) { 2574 VarDecl *IDecl = dyn_cast<VarDecl>(ID); 2575 if (!IDecl) 2576 continue; 2577 QualType T = IDecl->getType(); 2578 2579 if (T->isVariableArrayType()) { 2580 const VariableArrayType *VAT = Context.getAsVariableArrayType(T); 2581 2582 // FIXME: This won't give the correct result for 2583 // int a[10][n]; 2584 SourceRange SizeRange = VAT->getSizeExpr()->getSourceRange(); 2585 if (IDecl->isFileVarDecl()) { 2586 Diag(IDecl->getLocation(), diag::err_vla_decl_in_file_scope) << 2587 SizeRange; 2588 2589 IDecl->setInvalidDecl(); 2590 } else { 2591 // C99 6.7.5.2p2: If an identifier is declared to be an object with 2592 // static storage duration, it shall not have a variable length array. 2593 if (IDecl->getStorageClass() == VarDecl::Static) { 2594 Diag(IDecl->getLocation(), diag::err_vla_decl_has_static_storage) 2595 << SizeRange; 2596 IDecl->setInvalidDecl(); 2597 } else if (IDecl->getStorageClass() == VarDecl::Extern) { 2598 Diag(IDecl->getLocation(), diag::err_vla_decl_has_extern_linkage) 2599 << SizeRange; 2600 IDecl->setInvalidDecl(); 2601 } 2602 } 2603 } else if (T->isVariablyModifiedType()) { 2604 if (IDecl->isFileVarDecl()) { 2605 Diag(IDecl->getLocation(), diag::err_vm_decl_in_file_scope); 2606 IDecl->setInvalidDecl(); 2607 } else { 2608 if (IDecl->getStorageClass() == VarDecl::Extern) { 2609 Diag(IDecl->getLocation(), diag::err_vm_decl_has_extern_linkage); 2610 IDecl->setInvalidDecl(); 2611 } 2612 } 2613 } 2614 2615 // Block scope. C99 6.7p7: If an identifier for an object is declared with 2616 // no linkage (C99 6.2.2p6), the type for the object shall be complete... 2617 if (IDecl->isBlockVarDecl() && 2618 IDecl->getStorageClass() != VarDecl::Extern) { 2619 if (!IDecl->isInvalidDecl() && 2620 DiagnoseIncompleteType(IDecl->getLocation(), T, 2621 diag::err_typecheck_decl_incomplete_type)) 2622 IDecl->setInvalidDecl(); 2623 } 2624 // File scope. C99 6.9.2p2: A declaration of an identifier for and 2625 // object that has file scope without an initializer, and without a 2626 // storage-class specifier or with the storage-class specifier "static", 2627 // constitutes a tentative definition. Note: A tentative definition with 2628 // external linkage is valid (C99 6.2.2p5). 2629 if (isTentativeDefinition(IDecl)) { 2630 if (T->isIncompleteArrayType()) { 2631 // C99 6.9.2 (p2, p5): Implicit initialization causes an incomplete 2632 // array to be completed. Don't issue a diagnostic. 2633 } else if (!IDecl->isInvalidDecl() && 2634 DiagnoseIncompleteType(IDecl->getLocation(), T, 2635 diag::err_typecheck_decl_incomplete_type)) 2636 // C99 6.9.2p3: If the declaration of an identifier for an object is 2637 // a tentative definition and has internal linkage (C99 6.2.2p3), the 2638 // declared type shall not be an incomplete type. 2639 IDecl->setInvalidDecl(); 2640 } 2641 if (IDecl->isFileVarDecl()) 2642 CheckForFileScopedRedefinitions(S, IDecl); 2643 } 2644 return NewGroup; 2645} 2646 2647/// ActOnParamDeclarator - Called from Parser::ParseFunctionDeclarator() 2648/// to introduce parameters into function prototype scope. 2649Sema::DeclTy * 2650Sema::ActOnParamDeclarator(Scope *S, Declarator &D) { 2651 const DeclSpec &DS = D.getDeclSpec(); 2652 2653 // Verify C99 6.7.5.3p2: The only SCS allowed is 'register'. 2654 VarDecl::StorageClass StorageClass = VarDecl::None; 2655 if (DS.getStorageClassSpec() == DeclSpec::SCS_register) { 2656 StorageClass = VarDecl::Register; 2657 } else if (DS.getStorageClassSpec() != DeclSpec::SCS_unspecified) { 2658 Diag(DS.getStorageClassSpecLoc(), 2659 diag::err_invalid_storage_class_in_func_decl); 2660 D.getMutableDeclSpec().ClearStorageClassSpecs(); 2661 } 2662 if (DS.isThreadSpecified()) { 2663 Diag(DS.getThreadSpecLoc(), 2664 diag::err_invalid_storage_class_in_func_decl); 2665 D.getMutableDeclSpec().ClearStorageClassSpecs(); 2666 } 2667 2668 // Check that there are no default arguments inside the type of this 2669 // parameter (C++ only). 2670 if (getLangOptions().CPlusPlus) 2671 CheckExtraCXXDefaultArguments(D); 2672 2673 // In this context, we *do not* check D.getInvalidType(). If the declarator 2674 // type was invalid, GetTypeForDeclarator() still returns a "valid" type, 2675 // though it will not reflect the user specified type. 2676 QualType parmDeclType = GetTypeForDeclarator(D, S); 2677 2678 assert(!parmDeclType.isNull() && "GetTypeForDeclarator() returned null type"); 2679 2680 // TODO: CHECK FOR CONFLICTS, multiple decls with same name in one scope. 2681 // Can this happen for params? We already checked that they don't conflict 2682 // among each other. Here they can only shadow globals, which is ok. 2683 IdentifierInfo *II = D.getIdentifier(); 2684 if (II) { 2685 if (NamedDecl *PrevDecl = LookupName(S, II, LookupOrdinaryName)) { 2686 if (PrevDecl->isTemplateParameter()) { 2687 // Maybe we will complain about the shadowed template parameter. 2688 DiagnoseTemplateParameterShadow(D.getIdentifierLoc(), PrevDecl); 2689 // Just pretend that we didn't see the previous declaration. 2690 PrevDecl = 0; 2691 } else if (S->isDeclScope(PrevDecl)) { 2692 Diag(D.getIdentifierLoc(), diag::err_param_redefinition) << II; 2693 2694 // Recover by removing the name 2695 II = 0; 2696 D.SetIdentifier(0, D.getIdentifierLoc()); 2697 } 2698 } 2699 } 2700 2701 // Perform the default function/array conversion (C99 6.7.5.3p[7,8]). 2702 // Doing the promotion here has a win and a loss. The win is the type for 2703 // both Decl's and DeclRefExpr's will match (a convenient invariant for the 2704 // code generator). The loss is the orginal type isn't preserved. For example: 2705 // 2706 // void func(int parmvardecl[5]) { // convert "int [5]" to "int *" 2707 // int blockvardecl[5]; 2708 // sizeof(parmvardecl); // size == 4 2709 // sizeof(blockvardecl); // size == 20 2710 // } 2711 // 2712 // For expressions, all implicit conversions are captured using the 2713 // ImplicitCastExpr AST node (we have no such mechanism for Decl's). 2714 // 2715 // FIXME: If a source translation tool needs to see the original type, then 2716 // we need to consider storing both types (in ParmVarDecl)... 2717 // 2718 if (parmDeclType->isArrayType()) { 2719 // int x[restrict 4] -> int *restrict 2720 parmDeclType = Context.getArrayDecayedType(parmDeclType); 2721 } else if (parmDeclType->isFunctionType()) 2722 parmDeclType = Context.getPointerType(parmDeclType); 2723 2724 ParmVarDecl *New = ParmVarDecl::Create(Context, CurContext, 2725 D.getIdentifierLoc(), II, 2726 parmDeclType, StorageClass, 2727 0); 2728 2729 if (D.getInvalidType()) 2730 New->setInvalidDecl(); 2731 2732 // Parameter declarators cannot be qualified (C++ [dcl.meaning]p1). 2733 if (D.getCXXScopeSpec().isSet()) { 2734 Diag(D.getIdentifierLoc(), diag::err_qualified_param_declarator) 2735 << D.getCXXScopeSpec().getRange(); 2736 New->setInvalidDecl(); 2737 } 2738 2739 // Add the parameter declaration into this scope. 2740 S->AddDecl(New); 2741 if (II) 2742 IdResolver.AddDecl(New); 2743 2744 ProcessDeclAttributes(New, D); 2745 return New; 2746 2747} 2748 2749void Sema::ActOnFinishKNRParamDeclarations(Scope *S, Declarator &D) { 2750 assert(D.getTypeObject(0).Kind == DeclaratorChunk::Function && 2751 "Not a function declarator!"); 2752 DeclaratorChunk::FunctionTypeInfo &FTI = D.getTypeObject(0).Fun; 2753 2754 // Verify 6.9.1p6: 'every identifier in the identifier list shall be declared' 2755 // for a K&R function. 2756 if (!FTI.hasPrototype) { 2757 for (unsigned i = 0, e = FTI.NumArgs; i != e; ++i) { 2758 if (FTI.ArgInfo[i].Param == 0) { 2759 Diag(FTI.ArgInfo[i].IdentLoc, diag::ext_param_not_declared) 2760 << FTI.ArgInfo[i].Ident; 2761 // Implicitly declare the argument as type 'int' for lack of a better 2762 // type. 2763 DeclSpec DS; 2764 const char* PrevSpec; // unused 2765 DS.SetTypeSpecType(DeclSpec::TST_int, FTI.ArgInfo[i].IdentLoc, 2766 PrevSpec); 2767 Declarator ParamD(DS, Declarator::KNRTypeListContext); 2768 ParamD.SetIdentifier(FTI.ArgInfo[i].Ident, FTI.ArgInfo[i].IdentLoc); 2769 FTI.ArgInfo[i].Param = ActOnParamDeclarator(S, ParamD); 2770 } 2771 } 2772 } 2773} 2774 2775Sema::DeclTy *Sema::ActOnStartOfFunctionDef(Scope *FnBodyScope, Declarator &D) { 2776 assert(getCurFunctionDecl() == 0 && "Function parsing confused"); 2777 assert(D.getTypeObject(0).Kind == DeclaratorChunk::Function && 2778 "Not a function declarator!"); 2779 DeclaratorChunk::FunctionTypeInfo &FTI = D.getTypeObject(0).Fun; 2780 2781 if (FTI.hasPrototype) { 2782 // FIXME: Diagnose arguments without names in C. 2783 } 2784 2785 Scope *ParentScope = FnBodyScope->getParent(); 2786 2787 return ActOnStartOfFunctionDef(FnBodyScope, 2788 ActOnDeclarator(ParentScope, D, 0, 2789 /*IsFunctionDefinition=*/true)); 2790} 2791 2792Sema::DeclTy *Sema::ActOnStartOfFunctionDef(Scope *FnBodyScope, DeclTy *D) { 2793 Decl *decl = static_cast<Decl*>(D); 2794 FunctionDecl *FD = cast<FunctionDecl>(decl); 2795 2796 // See if this is a redefinition. 2797 const FunctionDecl *Definition; 2798 if (FD->getBody(Definition)) { 2799 Diag(FD->getLocation(), diag::err_redefinition) << FD->getDeclName(); 2800 Diag(Definition->getLocation(), diag::note_previous_definition); 2801 } 2802 2803 // Builtin functions cannot be defined. 2804 if (unsigned BuiltinID = FD->getBuiltinID(Context)) { 2805 if (Context.BuiltinInfo.isPredefinedLibFunction(BuiltinID)) { 2806 Diag(FD->getLocation(), diag::err_builtin_lib_definition) << FD; 2807 Diag(FD->getLocation(), diag::note_builtin_lib_def_freestanding); 2808 } else 2809 Diag(FD->getLocation(), diag::err_builtin_definition) << FD; 2810 FD->setInvalidDecl(); 2811 } 2812 2813 PushDeclContext(FnBodyScope, FD); 2814 2815 // Check the validity of our function parameters 2816 CheckParmsForFunctionDef(FD); 2817 2818 // Introduce our parameters into the function scope 2819 for (unsigned p = 0, NumParams = FD->getNumParams(); p < NumParams; ++p) { 2820 ParmVarDecl *Param = FD->getParamDecl(p); 2821 Param->setOwningFunction(FD); 2822 2823 // If this has an identifier, add it to the scope stack. 2824 if (Param->getIdentifier()) 2825 PushOnScopeChains(Param, FnBodyScope); 2826 } 2827 2828 // Checking attributes of current function definition 2829 // dllimport attribute. 2830 if (FD->getAttr<DLLImportAttr>() && (!FD->getAttr<DLLExportAttr>())) { 2831 // dllimport attribute cannot be applied to definition. 2832 if (!(FD->getAttr<DLLImportAttr>())->isInherited()) { 2833 Diag(FD->getLocation(), 2834 diag::err_attribute_can_be_applied_only_to_symbol_declaration) 2835 << "dllimport"; 2836 FD->setInvalidDecl(); 2837 return FD; 2838 } else { 2839 // If a symbol previously declared dllimport is later defined, the 2840 // attribute is ignored in subsequent references, and a warning is 2841 // emitted. 2842 Diag(FD->getLocation(), 2843 diag::warn_redeclaration_without_attribute_prev_attribute_ignored) 2844 << FD->getNameAsCString() << "dllimport"; 2845 } 2846 } 2847 return FD; 2848} 2849 2850Sema::DeclTy *Sema::ActOnFinishFunctionBody(DeclTy *D, StmtArg BodyArg) { 2851 Decl *dcl = static_cast<Decl *>(D); 2852 Stmt *Body = static_cast<Stmt*>(BodyArg.release()); 2853 if (FunctionDecl *FD = dyn_cast_or_null<FunctionDecl>(dcl)) { 2854 FD->setBody(Body); 2855 assert(FD == getCurFunctionDecl() && "Function parsing confused"); 2856 } else if (ObjCMethodDecl *MD = dyn_cast_or_null<ObjCMethodDecl>(dcl)) { 2857 assert(MD == getCurMethodDecl() && "Method parsing confused"); 2858 MD->setBody((Stmt*)Body); 2859 } else { 2860 Body->Destroy(Context); 2861 return 0; 2862 } 2863 PopDeclContext(); 2864 // Verify and clean out per-function state. 2865 2866 // Check goto/label use. 2867 for (llvm::DenseMap<IdentifierInfo*, LabelStmt*>::iterator 2868 I = LabelMap.begin(), E = LabelMap.end(); I != E; ++I) { 2869 // Verify that we have no forward references left. If so, there was a goto 2870 // or address of a label taken, but no definition of it. Label fwd 2871 // definitions are indicated with a null substmt. 2872 if (I->second->getSubStmt() == 0) { 2873 LabelStmt *L = I->second; 2874 // Emit error. 2875 Diag(L->getIdentLoc(), diag::err_undeclared_label_use) << L->getName(); 2876 2877 // At this point, we have gotos that use the bogus label. Stitch it into 2878 // the function body so that they aren't leaked and that the AST is well 2879 // formed. 2880 if (Body) { 2881#if 0 2882 // FIXME: Why do this? Having a 'push_back' in CompoundStmt is ugly, 2883 // and the AST is malformed anyway. We should just blow away 'L'. 2884 L->setSubStmt(new (Context) NullStmt(L->getIdentLoc())); 2885 cast<CompoundStmt>(Body)->push_back(L); 2886#else 2887 L->Destroy(Context); 2888#endif 2889 } else { 2890 // The whole function wasn't parsed correctly, just delete this. 2891 L->Destroy(Context); 2892 } 2893 } 2894 } 2895 LabelMap.clear(); 2896 2897 return D; 2898} 2899 2900/// ImplicitlyDefineFunction - An undeclared identifier was used in a function 2901/// call, forming a call to an implicitly defined function (per C99 6.5.1p2). 2902NamedDecl *Sema::ImplicitlyDefineFunction(SourceLocation Loc, 2903 IdentifierInfo &II, Scope *S) { 2904 // Extension in C99. Legal in C90, but warn about it. 2905 if (getLangOptions().C99) 2906 Diag(Loc, diag::ext_implicit_function_decl) << &II; 2907 else 2908 Diag(Loc, diag::warn_implicit_function_decl) << &II; 2909 2910 // FIXME: handle stuff like: 2911 // void foo() { extern float X(); } 2912 // void bar() { X(); } <-- implicit decl for X in another scope. 2913 2914 // Set a Declarator for the implicit definition: int foo(); 2915 const char *Dummy; 2916 DeclSpec DS; 2917 bool Error = DS.SetTypeSpecType(DeclSpec::TST_int, Loc, Dummy); 2918 Error = Error; // Silence warning. 2919 assert(!Error && "Error setting up implicit decl!"); 2920 Declarator D(DS, Declarator::BlockContext); 2921 D.AddTypeInfo(DeclaratorChunk::getFunction(false, false, 0, 0, 0, Loc, D), 2922 SourceLocation()); 2923 D.SetIdentifier(&II, Loc); 2924 2925 // Insert this function into translation-unit scope. 2926 2927 DeclContext *PrevDC = CurContext; 2928 CurContext = Context.getTranslationUnitDecl(); 2929 2930 FunctionDecl *FD = 2931 dyn_cast<FunctionDecl>(static_cast<Decl*>(ActOnDeclarator(TUScope, D, 0))); 2932 FD->setImplicit(); 2933 2934 CurContext = PrevDC; 2935 2936 AddKnownFunctionAttributes(FD); 2937 2938 return FD; 2939} 2940 2941/// \brief Adds any function attributes that we know a priori based on 2942/// the declaration of this function. 2943/// 2944/// These attributes can apply both to implicitly-declared builtins 2945/// (like __builtin___printf_chk) or to library-declared functions 2946/// like NSLog or printf. 2947void Sema::AddKnownFunctionAttributes(FunctionDecl *FD) { 2948 if (FD->isInvalidDecl()) 2949 return; 2950 2951 // If this is a built-in function, map its builtin attributes to 2952 // actual attributes. 2953 if (unsigned BuiltinID = FD->getBuiltinID(Context)) { 2954 // Handle printf-formatting attributes. 2955 unsigned FormatIdx; 2956 bool HasVAListArg; 2957 if (Context.BuiltinInfo.isPrintfLike(BuiltinID, FormatIdx, HasVAListArg)) { 2958 if (!FD->getAttr<FormatAttr>()) 2959 FD->addAttr(new FormatAttr("printf", FormatIdx + 1, FormatIdx + 2)); 2960 } 2961 2962 // Mark const if we don't care about errno and that is the only 2963 // thing preventing the function from being const. This allows 2964 // IRgen to use LLVM intrinsics for such functions. 2965 if (!getLangOptions().MathErrno && 2966 Context.BuiltinInfo.isConstWithoutErrno(BuiltinID)) { 2967 if (!FD->getAttr<ConstAttr>()) 2968 FD->addAttr(new ConstAttr()); 2969 } 2970 } 2971 2972 IdentifierInfo *Name = FD->getIdentifier(); 2973 if (!Name) 2974 return; 2975 if ((!getLangOptions().CPlusPlus && 2976 FD->getDeclContext()->isTranslationUnit()) || 2977 (isa<LinkageSpecDecl>(FD->getDeclContext()) && 2978 cast<LinkageSpecDecl>(FD->getDeclContext())->getLanguage() == 2979 LinkageSpecDecl::lang_c)) { 2980 // Okay: this could be a libc/libm/Objective-C function we know 2981 // about. 2982 } else 2983 return; 2984 2985 unsigned KnownID; 2986 for (KnownID = 0; KnownID != id_num_known_functions; ++KnownID) 2987 if (KnownFunctionIDs[KnownID] == Name) 2988 break; 2989 2990 switch (KnownID) { 2991 case id_NSLog: 2992 case id_NSLogv: 2993 if (const FormatAttr *Format = FD->getAttr<FormatAttr>()) { 2994 // FIXME: We known better than our headers. 2995 const_cast<FormatAttr *>(Format)->setType("printf"); 2996 } else 2997 FD->addAttr(new FormatAttr("printf", 1, 2)); 2998 break; 2999 3000 case id_asprintf: 3001 case id_vasprintf: 3002 if (!FD->getAttr<FormatAttr>()) 3003 FD->addAttr(new FormatAttr("printf", 2, 3)); 3004 break; 3005 3006 default: 3007 // Unknown function or known function without any attributes to 3008 // add. Do nothing. 3009 break; 3010 } 3011} 3012 3013TypedefDecl *Sema::ParseTypedefDecl(Scope *S, Declarator &D, QualType T, 3014 Decl *LastDeclarator) { 3015 assert(D.getIdentifier() && "Wrong callback for declspec without declarator"); 3016 assert(!T.isNull() && "GetTypeForDeclarator() returned null type"); 3017 3018 // Scope manipulation handled by caller. 3019 TypedefDecl *NewTD = TypedefDecl::Create(Context, CurContext, 3020 D.getIdentifierLoc(), 3021 D.getIdentifier(), 3022 T); 3023 NewTD->setNextDeclarator(LastDeclarator); 3024 if (D.getInvalidType()) 3025 NewTD->setInvalidDecl(); 3026 return NewTD; 3027} 3028 3029/// ActOnTag - This is invoked when we see 'struct foo' or 'struct {'. In the 3030/// former case, Name will be non-null. In the later case, Name will be null. 3031/// TagSpec indicates what kind of tag this is. TK indicates whether this is a 3032/// reference/declaration/definition of a tag. 3033Sema::DeclTy *Sema::ActOnTag(Scope *S, unsigned TagSpec, TagKind TK, 3034 SourceLocation KWLoc, const CXXScopeSpec &SS, 3035 IdentifierInfo *Name, SourceLocation NameLoc, 3036 AttributeList *Attr) { 3037 // If this is not a definition, it must have a name. 3038 assert((Name != 0 || TK == TK_Definition) && 3039 "Nameless record must be a definition!"); 3040 3041 TagDecl::TagKind Kind; 3042 switch (TagSpec) { 3043 default: assert(0 && "Unknown tag type!"); 3044 case DeclSpec::TST_struct: Kind = TagDecl::TK_struct; break; 3045 case DeclSpec::TST_union: Kind = TagDecl::TK_union; break; 3046 case DeclSpec::TST_class: Kind = TagDecl::TK_class; break; 3047 case DeclSpec::TST_enum: Kind = TagDecl::TK_enum; break; 3048 } 3049 3050 DeclContext *SearchDC = CurContext; 3051 DeclContext *DC = CurContext; 3052 NamedDecl *PrevDecl = 0; 3053 3054 bool Invalid = false; 3055 3056 if (Name && SS.isNotEmpty()) { 3057 // We have a nested-name tag ('struct foo::bar'). 3058 3059 // Check for invalid 'foo::'. 3060 if (SS.isInvalid()) { 3061 Name = 0; 3062 goto CreateNewDecl; 3063 } 3064 3065 DC = static_cast<DeclContext*>(SS.getScopeRep()); 3066 SearchDC = DC; 3067 // Look-up name inside 'foo::'. 3068 PrevDecl = dyn_cast_or_null<TagDecl>( 3069 LookupQualifiedName(DC, Name, LookupTagName, true).getAsDecl()); 3070 3071 // A tag 'foo::bar' must already exist. 3072 if (PrevDecl == 0) { 3073 Diag(NameLoc, diag::err_not_tag_in_scope) << Name << SS.getRange(); 3074 Name = 0; 3075 goto CreateNewDecl; 3076 } 3077 } else if (Name) { 3078 // If this is a named struct, check to see if there was a previous forward 3079 // declaration or definition. 3080 // FIXME: We're looking into outer scopes here, even when we 3081 // shouldn't be. Doing so can result in ambiguities that we 3082 // shouldn't be diagnosing. 3083 LookupResult R = LookupName(S, Name, LookupTagName, 3084 /*RedeclarationOnly=*/(TK != TK_Reference)); 3085 if (R.isAmbiguous()) { 3086 DiagnoseAmbiguousLookup(R, Name, NameLoc); 3087 // FIXME: This is not best way to recover from case like: 3088 // 3089 // struct S s; 3090 // 3091 // causes needless err_ovl_no_viable_function_in_init latter. 3092 Name = 0; 3093 PrevDecl = 0; 3094 Invalid = true; 3095 } 3096 else 3097 PrevDecl = R; 3098 3099 if (!getLangOptions().CPlusPlus && TK != TK_Reference) { 3100 // FIXME: This makes sure that we ignore the contexts associated 3101 // with C structs, unions, and enums when looking for a matching 3102 // tag declaration or definition. See the similar lookup tweak 3103 // in Sema::LookupName; is there a better way to deal with this? 3104 while (isa<RecordDecl>(SearchDC) || isa<EnumDecl>(SearchDC)) 3105 SearchDC = SearchDC->getParent(); 3106 } 3107 } 3108 3109 if (PrevDecl && PrevDecl->isTemplateParameter()) { 3110 // Maybe we will complain about the shadowed template parameter. 3111 DiagnoseTemplateParameterShadow(NameLoc, PrevDecl); 3112 // Just pretend that we didn't see the previous declaration. 3113 PrevDecl = 0; 3114 } 3115 3116 if (PrevDecl) { 3117 // If the previous declaration was deprecated, emit a warning. 3118 DiagnoseUseOfDeprecatedDecl(PrevDecl, NameLoc); 3119 3120 if (TagDecl *PrevTagDecl = dyn_cast<TagDecl>(PrevDecl)) { 3121 // If this is a use of a previous tag, or if the tag is already declared 3122 // in the same scope (so that the definition/declaration completes or 3123 // rementions the tag), reuse the decl. 3124 if (TK == TK_Reference || isDeclInScope(PrevDecl, SearchDC, S)) { 3125 // Make sure that this wasn't declared as an enum and now used as a 3126 // struct or something similar. 3127 if (PrevTagDecl->getTagKind() != Kind) { 3128 Diag(KWLoc, diag::err_use_with_wrong_tag) << Name; 3129 Diag(PrevDecl->getLocation(), diag::note_previous_use); 3130 // Recover by making this an anonymous redefinition. 3131 Name = 0; 3132 PrevDecl = 0; 3133 Invalid = true; 3134 } else { 3135 // If this is a use, just return the declaration we found. 3136 3137 // FIXME: In the future, return a variant or some other clue 3138 // for the consumer of this Decl to know it doesn't own it. 3139 // For our current ASTs this shouldn't be a problem, but will 3140 // need to be changed with DeclGroups. 3141 if (TK == TK_Reference) 3142 return PrevDecl; 3143 3144 // Diagnose attempts to redefine a tag. 3145 if (TK == TK_Definition) { 3146 if (TagDecl *Def = PrevTagDecl->getDefinition(Context)) { 3147 Diag(NameLoc, diag::err_redefinition) << Name; 3148 Diag(Def->getLocation(), diag::note_previous_definition); 3149 // If this is a redefinition, recover by making this 3150 // struct be anonymous, which will make any later 3151 // references get the previous definition. 3152 Name = 0; 3153 PrevDecl = 0; 3154 Invalid = true; 3155 } else { 3156 // If the type is currently being defined, complain 3157 // about a nested redefinition. 3158 TagType *Tag = cast<TagType>(Context.getTagDeclType(PrevTagDecl)); 3159 if (Tag->isBeingDefined()) { 3160 Diag(NameLoc, diag::err_nested_redefinition) << Name; 3161 Diag(PrevTagDecl->getLocation(), 3162 diag::note_previous_definition); 3163 Name = 0; 3164 PrevDecl = 0; 3165 Invalid = true; 3166 } 3167 } 3168 3169 // Okay, this is definition of a previously declared or referenced 3170 // tag PrevDecl. We're going to create a new Decl for it. 3171 } 3172 } 3173 // If we get here we have (another) forward declaration or we 3174 // have a definition. Just create a new decl. 3175 } else { 3176 // If we get here, this is a definition of a new tag type in a nested 3177 // scope, e.g. "struct foo; void bar() { struct foo; }", just create a 3178 // new decl/type. We set PrevDecl to NULL so that the entities 3179 // have distinct types. 3180 PrevDecl = 0; 3181 } 3182 // If we get here, we're going to create a new Decl. If PrevDecl 3183 // is non-NULL, it's a definition of the tag declared by 3184 // PrevDecl. If it's NULL, we have a new definition. 3185 } else { 3186 // PrevDecl is a namespace, template, or anything else 3187 // that lives in the IDNS_Tag identifier namespace. 3188 if (isDeclInScope(PrevDecl, SearchDC, S)) { 3189 // The tag name clashes with a namespace name, issue an error and 3190 // recover by making this tag be anonymous. 3191 Diag(NameLoc, diag::err_redefinition_different_kind) << Name; 3192 Diag(PrevDecl->getLocation(), diag::note_previous_definition); 3193 Name = 0; 3194 PrevDecl = 0; 3195 Invalid = true; 3196 } else { 3197 // The existing declaration isn't relevant to us; we're in a 3198 // new scope, so clear out the previous declaration. 3199 PrevDecl = 0; 3200 } 3201 } 3202 } else if (TK == TK_Reference && SS.isEmpty() && Name && 3203 (Kind != TagDecl::TK_enum)) { 3204 // C++ [basic.scope.pdecl]p5: 3205 // -- for an elaborated-type-specifier of the form 3206 // 3207 // class-key identifier 3208 // 3209 // if the elaborated-type-specifier is used in the 3210 // decl-specifier-seq or parameter-declaration-clause of a 3211 // function defined in namespace scope, the identifier is 3212 // declared as a class-name in the namespace that contains 3213 // the declaration; otherwise, except as a friend 3214 // declaration, the identifier is declared in the smallest 3215 // non-class, non-function-prototype scope that contains the 3216 // declaration. 3217 // 3218 // C99 6.7.2.3p8 has a similar (but not identical!) provision for 3219 // C structs and unions. 3220 3221 // Find the context where we'll be declaring the tag. 3222 // FIXME: We would like to maintain the current DeclContext as the 3223 // lexical context, 3224 while (SearchDC->isRecord()) 3225 SearchDC = SearchDC->getParent(); 3226 3227 // Find the scope where we'll be declaring the tag. 3228 while (S->isClassScope() || 3229 (getLangOptions().CPlusPlus && S->isFunctionPrototypeScope()) || 3230 ((S->getFlags() & Scope::DeclScope) == 0) || 3231 (S->getEntity() && 3232 ((DeclContext *)S->getEntity())->isTransparentContext())) 3233 S = S->getParent(); 3234 } 3235 3236CreateNewDecl: 3237 3238 // If there is an identifier, use the location of the identifier as the 3239 // location of the decl, otherwise use the location of the struct/union 3240 // keyword. 3241 SourceLocation Loc = NameLoc.isValid() ? NameLoc : KWLoc; 3242 3243 // Otherwise, create a new declaration. If there is a previous 3244 // declaration of the same entity, the two will be linked via 3245 // PrevDecl. 3246 TagDecl *New; 3247 3248 if (Kind == TagDecl::TK_enum) { 3249 // FIXME: Tag decls should be chained to any simultaneous vardecls, e.g.: 3250 // enum X { A, B, C } D; D should chain to X. 3251 New = EnumDecl::Create(Context, SearchDC, Loc, Name, 3252 cast_or_null<EnumDecl>(PrevDecl)); 3253 // If this is an undefined enum, warn. 3254 if (TK != TK_Definition) Diag(Loc, diag::ext_forward_ref_enum); 3255 } else { 3256 // struct/union/class 3257 3258 // FIXME: Tag decls should be chained to any simultaneous vardecls, e.g.: 3259 // struct X { int A; } D; D should chain to X. 3260 if (getLangOptions().CPlusPlus) 3261 // FIXME: Look for a way to use RecordDecl for simple structs. 3262 New = CXXRecordDecl::Create(Context, Kind, SearchDC, Loc, Name, 3263 cast_or_null<CXXRecordDecl>(PrevDecl)); 3264 else 3265 New = RecordDecl::Create(Context, Kind, SearchDC, Loc, Name, 3266 cast_or_null<RecordDecl>(PrevDecl)); 3267 } 3268 3269 if (Kind != TagDecl::TK_enum) { 3270 // Handle #pragma pack: if the #pragma pack stack has non-default 3271 // alignment, make up a packed attribute for this decl. These 3272 // attributes are checked when the ASTContext lays out the 3273 // structure. 3274 // 3275 // It is important for implementing the correct semantics that this 3276 // happen here (in act on tag decl). The #pragma pack stack is 3277 // maintained as a result of parser callbacks which can occur at 3278 // many points during the parsing of a struct declaration (because 3279 // the #pragma tokens are effectively skipped over during the 3280 // parsing of the struct). 3281 if (unsigned Alignment = getPragmaPackAlignment()) 3282 New->addAttr(new PackedAttr(Alignment * 8)); 3283 } 3284 3285 if (getLangOptions().CPlusPlus && SS.isEmpty() && Name && !Invalid) { 3286 // C++ [dcl.typedef]p3: 3287 // [...] Similarly, in a given scope, a class or enumeration 3288 // shall not be declared with the same name as a typedef-name 3289 // that is declared in that scope and refers to a type other 3290 // than the class or enumeration itself. 3291 LookupResult Lookup = LookupName(S, Name, LookupOrdinaryName, true); 3292 TypedefDecl *PrevTypedef = 0; 3293 if (Lookup.getKind() == LookupResult::Found) 3294 PrevTypedef = dyn_cast<TypedefDecl>(Lookup.getAsDecl()); 3295 3296 if (PrevTypedef && isDeclInScope(PrevTypedef, SearchDC, S) && 3297 Context.getCanonicalType(Context.getTypeDeclType(PrevTypedef)) != 3298 Context.getCanonicalType(Context.getTypeDeclType(New))) { 3299 Diag(Loc, diag::err_tag_definition_of_typedef) 3300 << Context.getTypeDeclType(New) 3301 << PrevTypedef->getUnderlyingType(); 3302 Diag(PrevTypedef->getLocation(), diag::note_previous_definition); 3303 Invalid = true; 3304 } 3305 } 3306 3307 if (Invalid) 3308 New->setInvalidDecl(); 3309 3310 if (Attr) 3311 ProcessDeclAttributeList(New, Attr); 3312 3313 // If we're declaring or defining a tag in function prototype scope 3314 // in C, note that this type can only be used within the function. 3315 if (Name && S->isFunctionPrototypeScope() && !getLangOptions().CPlusPlus) 3316 Diag(Loc, diag::warn_decl_in_param_list) << Context.getTagDeclType(New); 3317 3318 // Set the lexical context. If the tag has a C++ scope specifier, the 3319 // lexical context will be different from the semantic context. 3320 New->setLexicalDeclContext(CurContext); 3321 3322 if (TK == TK_Definition) 3323 New->startDefinition(); 3324 3325 // If this has an identifier, add it to the scope stack. 3326 if (Name) { 3327 S = getNonFieldDeclScope(S); 3328 PushOnScopeChains(New, S); 3329 } else { 3330 CurContext->addDecl(New); 3331 } 3332 3333 return New; 3334} 3335 3336void Sema::ActOnTagStartDefinition(Scope *S, DeclTy *TagD) { 3337 AdjustDeclIfTemplate(TagD); 3338 TagDecl *Tag = cast<TagDecl>((Decl *)TagD); 3339 3340 // Enter the tag context. 3341 PushDeclContext(S, Tag); 3342 3343 if (CXXRecordDecl *Record = dyn_cast<CXXRecordDecl>(Tag)) { 3344 FieldCollector->StartClass(); 3345 3346 if (Record->getIdentifier()) { 3347 // C++ [class]p2: 3348 // [...] The class-name is also inserted into the scope of the 3349 // class itself; this is known as the injected-class-name. For 3350 // purposes of access checking, the injected-class-name is treated 3351 // as if it were a public member name. 3352 RecordDecl *InjectedClassName 3353 = CXXRecordDecl::Create(Context, Record->getTagKind(), 3354 CurContext, Record->getLocation(), 3355 Record->getIdentifier(), Record); 3356 InjectedClassName->setImplicit(); 3357 PushOnScopeChains(InjectedClassName, S); 3358 } 3359 } 3360} 3361 3362void Sema::ActOnTagFinishDefinition(Scope *S, DeclTy *TagD) { 3363 AdjustDeclIfTemplate(TagD); 3364 TagDecl *Tag = cast<TagDecl>((Decl *)TagD); 3365 3366 if (isa<CXXRecordDecl>(Tag)) 3367 FieldCollector->FinishClass(); 3368 3369 // Exit this scope of this tag's definition. 3370 PopDeclContext(); 3371 3372 // Notify the consumer that we've defined a tag. 3373 Consumer.HandleTagDeclDefinition(Tag); 3374} 3375 3376/// TryToFixInvalidVariablyModifiedType - Helper method to turn variable array 3377/// types into constant array types in certain situations which would otherwise 3378/// be errors (for GCC compatibility). 3379static QualType TryToFixInvalidVariablyModifiedType(QualType T, 3380 ASTContext &Context) { 3381 // This method tries to turn a variable array into a constant 3382 // array even when the size isn't an ICE. This is necessary 3383 // for compatibility with code that depends on gcc's buggy 3384 // constant expression folding, like struct {char x[(int)(char*)2];} 3385 const VariableArrayType* VLATy = dyn_cast<VariableArrayType>(T); 3386 if (!VLATy) return QualType(); 3387 3388 Expr::EvalResult EvalResult; 3389 if (!VLATy->getSizeExpr() || 3390 !VLATy->getSizeExpr()->Evaluate(EvalResult, Context)) 3391 return QualType(); 3392 3393 assert(EvalResult.Val.isInt() && "Size expressions must be integers!"); 3394 llvm::APSInt &Res = EvalResult.Val.getInt(); 3395 if (Res >= llvm::APSInt(Res.getBitWidth(), Res.isUnsigned())) 3396 return Context.getConstantArrayType(VLATy->getElementType(), 3397 Res, ArrayType::Normal, 0); 3398 return QualType(); 3399} 3400 3401bool Sema::VerifyBitField(SourceLocation FieldLoc, IdentifierInfo *FieldName, 3402 QualType FieldTy, const Expr *BitWidth) { 3403 // FIXME: 6.7.2.1p4 - verify the field type. 3404 3405 llvm::APSInt Value; 3406 if (VerifyIntegerConstantExpression(BitWidth, &Value)) 3407 return true; 3408 3409 // Zero-width bitfield is ok for anonymous field. 3410 if (Value == 0 && FieldName) 3411 return Diag(FieldLoc, diag::err_bitfield_has_zero_width) << FieldName; 3412 3413 if (Value.isNegative()) 3414 return Diag(FieldLoc, diag::err_bitfield_has_negative_width) << FieldName; 3415 3416 uint64_t TypeSize = Context.getTypeSize(FieldTy); 3417 // FIXME: We won't need the 0 size once we check that the field type is valid. 3418 if (TypeSize && Value.getZExtValue() > TypeSize) 3419 return Diag(FieldLoc, diag::err_bitfield_width_exceeds_type_size) 3420 << FieldName << (unsigned)TypeSize; 3421 3422 return false; 3423} 3424 3425/// ActOnField - Each field of a struct/union/class is passed into this in order 3426/// to create a FieldDecl object for it. 3427Sema::DeclTy *Sema::ActOnField(Scope *S, DeclTy *TagD, 3428 SourceLocation DeclStart, 3429 Declarator &D, ExprTy *BitfieldWidth) { 3430 IdentifierInfo *II = D.getIdentifier(); 3431 Expr *BitWidth = (Expr*)BitfieldWidth; 3432 SourceLocation Loc = DeclStart; 3433 RecordDecl *Record = (RecordDecl *)TagD; 3434 if (II) Loc = D.getIdentifierLoc(); 3435 3436 // FIXME: Unnamed fields can be handled in various different ways, for 3437 // example, unnamed unions inject all members into the struct namespace! 3438 3439 QualType T = GetTypeForDeclarator(D, S); 3440 assert(!T.isNull() && "GetTypeForDeclarator() returned null type"); 3441 bool InvalidDecl = false; 3442 3443 // C99 6.7.2.1p8: A member of a structure or union may have any type other 3444 // than a variably modified type. 3445 if (T->isVariablyModifiedType()) { 3446 QualType FixedTy = TryToFixInvalidVariablyModifiedType(T, Context); 3447 if (!FixedTy.isNull()) { 3448 Diag(Loc, diag::warn_illegal_constant_array_size); 3449 T = FixedTy; 3450 } else { 3451 Diag(Loc, diag::err_typecheck_field_variable_size); 3452 T = Context.IntTy; 3453 InvalidDecl = true; 3454 } 3455 } 3456 3457 if (BitWidth) { 3458 if (VerifyBitField(Loc, II, T, BitWidth)) 3459 InvalidDecl = true; 3460 } else { 3461 // Not a bitfield. 3462 3463 // validate II. 3464 3465 } 3466 3467 // FIXME: Chain fielddecls together. 3468 FieldDecl *NewFD; 3469 3470 NewFD = FieldDecl::Create(Context, Record, 3471 Loc, II, T, BitWidth, 3472 D.getDeclSpec().getStorageClassSpec() == 3473 DeclSpec::SCS_mutable); 3474 3475 if (II) { 3476 NamedDecl *PrevDecl = LookupName(S, II, LookupMemberName, true); 3477 if (PrevDecl && isDeclInScope(PrevDecl, CurContext, S) 3478 && !isa<TagDecl>(PrevDecl)) { 3479 Diag(Loc, diag::err_duplicate_member) << II; 3480 Diag(PrevDecl->getLocation(), diag::note_previous_declaration); 3481 NewFD->setInvalidDecl(); 3482 Record->setInvalidDecl(); 3483 } 3484 } 3485 3486 if (getLangOptions().CPlusPlus) { 3487 CheckExtraCXXDefaultArguments(D); 3488 if (!T->isPODType()) 3489 cast<CXXRecordDecl>(Record)->setPOD(false); 3490 } 3491 3492 ProcessDeclAttributes(NewFD, D); 3493 3494 if (D.getInvalidType() || InvalidDecl) 3495 NewFD->setInvalidDecl(); 3496 3497 if (II) { 3498 PushOnScopeChains(NewFD, S); 3499 } else 3500 Record->addDecl(NewFD); 3501 3502 return NewFD; 3503} 3504 3505/// TranslateIvarVisibility - Translate visibility from a token ID to an 3506/// AST enum value. 3507static ObjCIvarDecl::AccessControl 3508TranslateIvarVisibility(tok::ObjCKeywordKind ivarVisibility) { 3509 switch (ivarVisibility) { 3510 default: assert(0 && "Unknown visitibility kind"); 3511 case tok::objc_private: return ObjCIvarDecl::Private; 3512 case tok::objc_public: return ObjCIvarDecl::Public; 3513 case tok::objc_protected: return ObjCIvarDecl::Protected; 3514 case tok::objc_package: return ObjCIvarDecl::Package; 3515 } 3516} 3517 3518/// ActOnIvar - Each ivar field of an objective-c class is passed into this 3519/// in order to create an IvarDecl object for it. 3520Sema::DeclTy *Sema::ActOnIvar(Scope *S, 3521 SourceLocation DeclStart, 3522 Declarator &D, ExprTy *BitfieldWidth, 3523 tok::ObjCKeywordKind Visibility) { 3524 3525 IdentifierInfo *II = D.getIdentifier(); 3526 Expr *BitWidth = (Expr*)BitfieldWidth; 3527 SourceLocation Loc = DeclStart; 3528 if (II) Loc = D.getIdentifierLoc(); 3529 3530 // FIXME: Unnamed fields can be handled in various different ways, for 3531 // example, unnamed unions inject all members into the struct namespace! 3532 3533 QualType T = GetTypeForDeclarator(D, S); 3534 assert(!T.isNull() && "GetTypeForDeclarator() returned null type"); 3535 bool InvalidDecl = false; 3536 3537 if (BitWidth) { 3538 // TODO: Validate. 3539 //printf("WARNING: BITFIELDS IGNORED!\n"); 3540 3541 // 6.7.2.1p3 3542 // 6.7.2.1p4 3543 3544 } else { 3545 // Not a bitfield. 3546 3547 // validate II. 3548 3549 } 3550 3551 // C99 6.7.2.1p8: A member of a structure or union may have any type other 3552 // than a variably modified type. 3553 if (T->isVariablyModifiedType()) { 3554 Diag(Loc, diag::err_typecheck_ivar_variable_size); 3555 InvalidDecl = true; 3556 } 3557 3558 // Get the visibility (access control) for this ivar. 3559 ObjCIvarDecl::AccessControl ac = 3560 Visibility != tok::objc_not_keyword ? TranslateIvarVisibility(Visibility) 3561 : ObjCIvarDecl::None; 3562 3563 // Construct the decl. 3564 ObjCIvarDecl *NewID = ObjCIvarDecl::Create(Context, Loc, II, T, ac, 3565 (Expr *)BitfieldWidth); 3566 3567 if (II) { 3568 NamedDecl *PrevDecl = LookupName(S, II, LookupMemberName, true); 3569 if (PrevDecl && isDeclInScope(PrevDecl, CurContext, S) 3570 && !isa<TagDecl>(PrevDecl)) { 3571 Diag(Loc, diag::err_duplicate_member) << II; 3572 Diag(PrevDecl->getLocation(), diag::note_previous_declaration); 3573 NewID->setInvalidDecl(); 3574 } 3575 } 3576 3577 // Process attributes attached to the ivar. 3578 ProcessDeclAttributes(NewID, D); 3579 3580 if (D.getInvalidType() || InvalidDecl) 3581 NewID->setInvalidDecl(); 3582 3583 if (II) { 3584 // FIXME: When interfaces are DeclContexts, we'll need to add 3585 // these to the interface. 3586 S->AddDecl(NewID); 3587 IdResolver.AddDecl(NewID); 3588 } 3589 3590 return NewID; 3591} 3592 3593void Sema::ActOnFields(Scope* S, 3594 SourceLocation RecLoc, DeclTy *RecDecl, 3595 DeclTy **Fields, unsigned NumFields, 3596 SourceLocation LBrac, SourceLocation RBrac, 3597 AttributeList *Attr) { 3598 Decl *EnclosingDecl = static_cast<Decl*>(RecDecl); 3599 assert(EnclosingDecl && "missing record or interface decl"); 3600 RecordDecl *Record = dyn_cast<RecordDecl>(EnclosingDecl); 3601 3602 // Verify that all the fields are okay. 3603 unsigned NumNamedMembers = 0; 3604 llvm::SmallVector<FieldDecl*, 32> RecFields; 3605 3606 for (unsigned i = 0; i != NumFields; ++i) { 3607 FieldDecl *FD = cast_or_null<FieldDecl>(static_cast<Decl*>(Fields[i])); 3608 assert(FD && "missing field decl"); 3609 3610 // Get the type for the field. 3611 Type *FDTy = FD->getType().getTypePtr(); 3612 3613 if (!FD->isAnonymousStructOrUnion()) { 3614 // Remember all fields written by the user. 3615 RecFields.push_back(FD); 3616 } 3617 3618 // C99 6.7.2.1p2 - A field may not be a function type. 3619 if (FDTy->isFunctionType()) { 3620 Diag(FD->getLocation(), diag::err_field_declared_as_function) 3621 << FD->getDeclName(); 3622 FD->setInvalidDecl(); 3623 EnclosingDecl->setInvalidDecl(); 3624 continue; 3625 } 3626 // C99 6.7.2.1p2 - A field may not be an incomplete type except... 3627 if (FDTy->isIncompleteType()) { 3628 if (!Record) { // Incomplete ivar type is always an error. 3629 DiagnoseIncompleteType(FD->getLocation(), FD->getType(), 3630 diag::err_field_incomplete); 3631 FD->setInvalidDecl(); 3632 EnclosingDecl->setInvalidDecl(); 3633 continue; 3634 } 3635 if (i != NumFields-1 || // ... that the last member ... 3636 !Record->isStruct() || // ... of a structure ... 3637 !FDTy->isArrayType()) { //... may have incomplete array type. 3638 DiagnoseIncompleteType(FD->getLocation(), FD->getType(), 3639 diag::err_field_incomplete); 3640 FD->setInvalidDecl(); 3641 EnclosingDecl->setInvalidDecl(); 3642 continue; 3643 } 3644 if (NumNamedMembers < 1) { //... must have more than named member ... 3645 Diag(FD->getLocation(), diag::err_flexible_array_empty_struct) 3646 << FD->getDeclName(); 3647 FD->setInvalidDecl(); 3648 EnclosingDecl->setInvalidDecl(); 3649 continue; 3650 } 3651 // Okay, we have a legal flexible array member at the end of the struct. 3652 if (Record) 3653 Record->setHasFlexibleArrayMember(true); 3654 } 3655 /// C99 6.7.2.1p2 - a struct ending in a flexible array member cannot be the 3656 /// field of another structure or the element of an array. 3657 if (const RecordType *FDTTy = FDTy->getAsRecordType()) { 3658 if (FDTTy->getDecl()->hasFlexibleArrayMember()) { 3659 // If this is a member of a union, then entire union becomes "flexible". 3660 if (Record && Record->isUnion()) { 3661 Record->setHasFlexibleArrayMember(true); 3662 } else { 3663 // If this is a struct/class and this is not the last element, reject 3664 // it. Note that GCC supports variable sized arrays in the middle of 3665 // structures. 3666 if (i != NumFields-1) { 3667 Diag(FD->getLocation(), diag::err_variable_sized_type_in_struct) 3668 << FD->getDeclName(); 3669 FD->setInvalidDecl(); 3670 EnclosingDecl->setInvalidDecl(); 3671 continue; 3672 } 3673 // We support flexible arrays at the end of structs in other structs 3674 // as an extension. 3675 Diag(FD->getLocation(), diag::ext_flexible_array_in_struct) 3676 << FD->getDeclName(); 3677 if (Record) 3678 Record->setHasFlexibleArrayMember(true); 3679 } 3680 } 3681 } 3682 /// A field cannot be an Objective-c object 3683 if (FDTy->isObjCInterfaceType()) { 3684 Diag(FD->getLocation(), diag::err_statically_allocated_object) 3685 << FD->getDeclName(); 3686 FD->setInvalidDecl(); 3687 EnclosingDecl->setInvalidDecl(); 3688 continue; 3689 } 3690 // Keep track of the number of named members. 3691 if (FD->getIdentifier()) 3692 ++NumNamedMembers; 3693 } 3694 3695 // Okay, we successfully defined 'Record'. 3696 if (Record) { 3697 Record->completeDefinition(Context); 3698 } else { 3699 ObjCIvarDecl **ClsFields = reinterpret_cast<ObjCIvarDecl**>(&RecFields[0]); 3700 if (ObjCInterfaceDecl *ID = dyn_cast<ObjCInterfaceDecl>(EnclosingDecl)) { 3701 ID->addInstanceVariablesToClass(ClsFields, RecFields.size(), RBrac); 3702 // Must enforce the rule that ivars in the base classes may not be 3703 // duplicates. 3704 if (ID->getSuperClass()) { 3705 for (ObjCInterfaceDecl::ivar_iterator IVI = ID->ivar_begin(), 3706 IVE = ID->ivar_end(); IVI != IVE; ++IVI) { 3707 ObjCIvarDecl* Ivar = (*IVI); 3708 IdentifierInfo *II = Ivar->getIdentifier(); 3709 ObjCIvarDecl* prevIvar = ID->getSuperClass()->lookupInstanceVariable(II); 3710 if (prevIvar) { 3711 Diag(Ivar->getLocation(), diag::err_duplicate_member) << II; 3712 Diag(prevIvar->getLocation(), diag::note_previous_declaration); 3713 } 3714 } 3715 } 3716 } 3717 else if (ObjCImplementationDecl *IMPDecl = 3718 dyn_cast<ObjCImplementationDecl>(EnclosingDecl)) { 3719 assert(IMPDecl && "ActOnFields - missing ObjCImplementationDecl"); 3720 IMPDecl->ObjCAddInstanceVariablesToClassImpl(ClsFields, RecFields.size()); 3721 CheckImplementationIvars(IMPDecl, ClsFields, RecFields.size(), RBrac); 3722 } 3723 } 3724 3725 if (Attr) 3726 ProcessDeclAttributeList(Record, Attr); 3727} 3728 3729Sema::DeclTy *Sema::ActOnEnumConstant(Scope *S, DeclTy *theEnumDecl, 3730 DeclTy *lastEnumConst, 3731 SourceLocation IdLoc, IdentifierInfo *Id, 3732 SourceLocation EqualLoc, ExprTy *val) { 3733 EnumDecl *TheEnumDecl = cast<EnumDecl>(static_cast<Decl*>(theEnumDecl)); 3734 EnumConstantDecl *LastEnumConst = 3735 cast_or_null<EnumConstantDecl>(static_cast<Decl*>(lastEnumConst)); 3736 Expr *Val = static_cast<Expr*>(val); 3737 3738 // The scope passed in may not be a decl scope. Zip up the scope tree until 3739 // we find one that is. 3740 S = getNonFieldDeclScope(S); 3741 3742 // Verify that there isn't already something declared with this name in this 3743 // scope. 3744 NamedDecl *PrevDecl = LookupName(S, Id, LookupOrdinaryName); 3745 if (PrevDecl && PrevDecl->isTemplateParameter()) { 3746 // Maybe we will complain about the shadowed template parameter. 3747 DiagnoseTemplateParameterShadow(IdLoc, PrevDecl); 3748 // Just pretend that we didn't see the previous declaration. 3749 PrevDecl = 0; 3750 } 3751 3752 if (PrevDecl) { 3753 // When in C++, we may get a TagDecl with the same name; in this case the 3754 // enum constant will 'hide' the tag. 3755 assert((getLangOptions().CPlusPlus || !isa<TagDecl>(PrevDecl)) && 3756 "Received TagDecl when not in C++!"); 3757 if (!isa<TagDecl>(PrevDecl) && isDeclInScope(PrevDecl, CurContext, S)) { 3758 if (isa<EnumConstantDecl>(PrevDecl)) 3759 Diag(IdLoc, diag::err_redefinition_of_enumerator) << Id; 3760 else 3761 Diag(IdLoc, diag::err_redefinition) << Id; 3762 Diag(PrevDecl->getLocation(), diag::note_previous_definition); 3763 Val->Destroy(Context); 3764 return 0; 3765 } 3766 } 3767 3768 llvm::APSInt EnumVal(32); 3769 QualType EltTy; 3770 if (Val) { 3771 // Make sure to promote the operand type to int. 3772 UsualUnaryConversions(Val); 3773 3774 // C99 6.7.2.2p2: Make sure we have an integer constant expression. 3775 SourceLocation ExpLoc; 3776 if (VerifyIntegerConstantExpression(Val, &EnumVal)) { 3777 Val->Destroy(Context); 3778 Val = 0; // Just forget about it. 3779 } else { 3780 EltTy = Val->getType(); 3781 } 3782 } 3783 3784 if (!Val) { 3785 if (LastEnumConst) { 3786 // Assign the last value + 1. 3787 EnumVal = LastEnumConst->getInitVal(); 3788 ++EnumVal; 3789 3790 // Check for overflow on increment. 3791 if (EnumVal < LastEnumConst->getInitVal()) 3792 Diag(IdLoc, diag::warn_enum_value_overflow); 3793 3794 EltTy = LastEnumConst->getType(); 3795 } else { 3796 // First value, set to zero. 3797 EltTy = Context.IntTy; 3798 EnumVal.zextOrTrunc(static_cast<uint32_t>(Context.getTypeSize(EltTy))); 3799 } 3800 } 3801 3802 EnumConstantDecl *New = 3803 EnumConstantDecl::Create(Context, TheEnumDecl, IdLoc, Id, EltTy, 3804 Val, EnumVal); 3805 3806 // Register this decl in the current scope stack. 3807 PushOnScopeChains(New, S); 3808 3809 return New; 3810} 3811 3812// FIXME: For consistency with ActOnFields(), we should have the parser 3813// pass in the source location for the left/right braces. 3814void Sema::ActOnEnumBody(SourceLocation EnumLoc, DeclTy *EnumDeclX, 3815 DeclTy **Elements, unsigned NumElements) { 3816 EnumDecl *Enum = cast<EnumDecl>(static_cast<Decl*>(EnumDeclX)); 3817 QualType EnumType = Context.getTypeDeclType(Enum); 3818 3819 // TODO: If the result value doesn't fit in an int, it must be a long or long 3820 // long value. ISO C does not support this, but GCC does as an extension, 3821 // emit a warning. 3822 unsigned IntWidth = Context.Target.getIntWidth(); 3823 3824 // Verify that all the values are okay, compute the size of the values, and 3825 // reverse the list. 3826 unsigned NumNegativeBits = 0; 3827 unsigned NumPositiveBits = 0; 3828 3829 // Keep track of whether all elements have type int. 3830 bool AllElementsInt = true; 3831 3832 for (unsigned i = 0; i != NumElements; ++i) { 3833 EnumConstantDecl *ECD = 3834 cast_or_null<EnumConstantDecl>(static_cast<Decl*>(Elements[i])); 3835 if (!ECD) continue; // Already issued a diagnostic. 3836 3837 // If the enum value doesn't fit in an int, emit an extension warning. 3838 const llvm::APSInt &InitVal = ECD->getInitVal(); 3839 assert(InitVal.getBitWidth() >= IntWidth && 3840 "Should have promoted value to int"); 3841 if (InitVal.getBitWidth() > IntWidth) { 3842 llvm::APSInt V(InitVal); 3843 V.trunc(IntWidth); 3844 V.extend(InitVal.getBitWidth()); 3845 if (V != InitVal) 3846 Diag(ECD->getLocation(), diag::ext_enum_value_not_int) 3847 << InitVal.toString(10); 3848 } 3849 3850 // Keep track of the size of positive and negative values. 3851 if (InitVal.isUnsigned() || InitVal.isNonNegative()) 3852 NumPositiveBits = std::max(NumPositiveBits, 3853 (unsigned)InitVal.getActiveBits()); 3854 else 3855 NumNegativeBits = std::max(NumNegativeBits, 3856 (unsigned)InitVal.getMinSignedBits()); 3857 3858 // Keep track of whether every enum element has type int (very commmon). 3859 if (AllElementsInt) 3860 AllElementsInt = ECD->getType() == Context.IntTy; 3861 } 3862 3863 // Figure out the type that should be used for this enum. 3864 // FIXME: Support attribute(packed) on enums and -fshort-enums. 3865 QualType BestType; 3866 unsigned BestWidth; 3867 3868 if (NumNegativeBits) { 3869 // If there is a negative value, figure out the smallest integer type (of 3870 // int/long/longlong) that fits. 3871 if (NumNegativeBits <= IntWidth && NumPositiveBits < IntWidth) { 3872 BestType = Context.IntTy; 3873 BestWidth = IntWidth; 3874 } else { 3875 BestWidth = Context.Target.getLongWidth(); 3876 3877 if (NumNegativeBits <= BestWidth && NumPositiveBits < BestWidth) 3878 BestType = Context.LongTy; 3879 else { 3880 BestWidth = Context.Target.getLongLongWidth(); 3881 3882 if (NumNegativeBits > BestWidth || NumPositiveBits >= BestWidth) 3883 Diag(Enum->getLocation(), diag::warn_enum_too_large); 3884 BestType = Context.LongLongTy; 3885 } 3886 } 3887 } else { 3888 // If there is no negative value, figure out which of uint, ulong, ulonglong 3889 // fits. 3890 if (NumPositiveBits <= IntWidth) { 3891 BestType = Context.UnsignedIntTy; 3892 BestWidth = IntWidth; 3893 } else if (NumPositiveBits <= 3894 (BestWidth = Context.Target.getLongWidth())) { 3895 BestType = Context.UnsignedLongTy; 3896 } else { 3897 BestWidth = Context.Target.getLongLongWidth(); 3898 assert(NumPositiveBits <= BestWidth && 3899 "How could an initializer get larger than ULL?"); 3900 BestType = Context.UnsignedLongLongTy; 3901 } 3902 } 3903 3904 // Loop over all of the enumerator constants, changing their types to match 3905 // the type of the enum if needed. 3906 for (unsigned i = 0; i != NumElements; ++i) { 3907 EnumConstantDecl *ECD = 3908 cast_or_null<EnumConstantDecl>(static_cast<Decl*>(Elements[i])); 3909 if (!ECD) continue; // Already issued a diagnostic. 3910 3911 // Standard C says the enumerators have int type, but we allow, as an 3912 // extension, the enumerators to be larger than int size. If each 3913 // enumerator value fits in an int, type it as an int, otherwise type it the 3914 // same as the enumerator decl itself. This means that in "enum { X = 1U }" 3915 // that X has type 'int', not 'unsigned'. 3916 if (ECD->getType() == Context.IntTy) { 3917 // Make sure the init value is signed. 3918 llvm::APSInt IV = ECD->getInitVal(); 3919 IV.setIsSigned(true); 3920 ECD->setInitVal(IV); 3921 3922 if (getLangOptions().CPlusPlus) 3923 // C++ [dcl.enum]p4: Following the closing brace of an 3924 // enum-specifier, each enumerator has the type of its 3925 // enumeration. 3926 ECD->setType(EnumType); 3927 continue; // Already int type. 3928 } 3929 3930 // Determine whether the value fits into an int. 3931 llvm::APSInt InitVal = ECD->getInitVal(); 3932 bool FitsInInt; 3933 if (InitVal.isUnsigned() || !InitVal.isNegative()) 3934 FitsInInt = InitVal.getActiveBits() < IntWidth; 3935 else 3936 FitsInInt = InitVal.getMinSignedBits() <= IntWidth; 3937 3938 // If it fits into an integer type, force it. Otherwise force it to match 3939 // the enum decl type. 3940 QualType NewTy; 3941 unsigned NewWidth; 3942 bool NewSign; 3943 if (FitsInInt) { 3944 NewTy = Context.IntTy; 3945 NewWidth = IntWidth; 3946 NewSign = true; 3947 } else if (ECD->getType() == BestType) { 3948 // Already the right type! 3949 if (getLangOptions().CPlusPlus) 3950 // C++ [dcl.enum]p4: Following the closing brace of an 3951 // enum-specifier, each enumerator has the type of its 3952 // enumeration. 3953 ECD->setType(EnumType); 3954 continue; 3955 } else { 3956 NewTy = BestType; 3957 NewWidth = BestWidth; 3958 NewSign = BestType->isSignedIntegerType(); 3959 } 3960 3961 // Adjust the APSInt value. 3962 InitVal.extOrTrunc(NewWidth); 3963 InitVal.setIsSigned(NewSign); 3964 ECD->setInitVal(InitVal); 3965 3966 // Adjust the Expr initializer and type. 3967 if (ECD->getInitExpr()) 3968 ECD->setInitExpr(new (Context) ImplicitCastExpr(NewTy, ECD->getInitExpr(), 3969 /*isLvalue=*/false)); 3970 if (getLangOptions().CPlusPlus) 3971 // C++ [dcl.enum]p4: Following the closing brace of an 3972 // enum-specifier, each enumerator has the type of its 3973 // enumeration. 3974 ECD->setType(EnumType); 3975 else 3976 ECD->setType(NewTy); 3977 } 3978 3979 Enum->completeDefinition(Context, BestType); 3980} 3981 3982Sema::DeclTy *Sema::ActOnFileScopeAsmDecl(SourceLocation Loc, 3983 ExprArg expr) { 3984 StringLiteral *AsmString = cast<StringLiteral>((Expr*)expr.release()); 3985 3986 return FileScopeAsmDecl::Create(Context, CurContext, Loc, AsmString); 3987} 3988 3989