SemaDecl.cpp revision 22bd905673a73ccb9b5e45a7038ec060c9650ffe
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, true, 1308 D.getIdentifierLoc()); 1309 } else { // Something like "int foo::x;" 1310 DC = static_cast<DeclContext*>(D.getCXXScopeSpec().getScopeRep()); 1311 PrevDecl = LookupQualifiedName(DC, Name, LookupOrdinaryName, true); 1312 1313 // C++ 7.3.1.2p2: 1314 // Members (including explicit specializations of templates) of a named 1315 // namespace can also be defined outside that namespace by explicit 1316 // qualification of the name being defined, provided that the entity being 1317 // defined was already declared in the namespace and the definition appears 1318 // after the point of declaration in a namespace that encloses the 1319 // declarations namespace. 1320 // 1321 // Note that we only check the context at this point. We don't yet 1322 // have enough information to make sure that PrevDecl is actually 1323 // the declaration we want to match. For example, given: 1324 // 1325 // class X { 1326 // void f(); 1327 // void f(float); 1328 // }; 1329 // 1330 // void X::f(int) { } // ill-formed 1331 // 1332 // In this case, PrevDecl will point to the overload set 1333 // containing the two f's declared in X, but neither of them 1334 // matches. 1335 1336 // First check whether we named the global scope. 1337 if (isa<TranslationUnitDecl>(DC)) { 1338 Diag(D.getIdentifierLoc(), diag::err_invalid_declarator_global_scope) 1339 << Name << D.getCXXScopeSpec().getRange(); 1340 } else if (!CurContext->Encloses(DC)) { 1341 // The qualifying scope doesn't enclose the original declaration. 1342 // Emit diagnostic based on current scope. 1343 SourceLocation L = D.getIdentifierLoc(); 1344 SourceRange R = D.getCXXScopeSpec().getRange(); 1345 if (isa<FunctionDecl>(CurContext)) 1346 Diag(L, diag::err_invalid_declarator_in_function) << Name << R; 1347 else 1348 Diag(L, diag::err_invalid_declarator_scope) 1349 << Name << cast<NamedDecl>(DC) << R; 1350 InvalidDecl = true; 1351 } 1352 } 1353 1354 if (PrevDecl && PrevDecl->isTemplateParameter()) { 1355 // Maybe we will complain about the shadowed template parameter. 1356 InvalidDecl = InvalidDecl 1357 || DiagnoseTemplateParameterShadow(D.getIdentifierLoc(), PrevDecl); 1358 // Just pretend that we didn't see the previous declaration. 1359 PrevDecl = 0; 1360 } 1361 1362 // In C++, the previous declaration we find might be a tag type 1363 // (class or enum). In this case, the new declaration will hide the 1364 // tag type. Note that this does does not apply if we're declaring a 1365 // typedef (C++ [dcl.typedef]p4). 1366 if (PrevDecl && PrevDecl->getIdentifierNamespace() == Decl::IDNS_Tag && 1367 D.getDeclSpec().getStorageClassSpec() != DeclSpec::SCS_typedef) 1368 PrevDecl = 0; 1369 1370 QualType R = GetTypeForDeclarator(D, S); 1371 assert(!R.isNull() && "GetTypeForDeclarator() returned null type"); 1372 1373 bool Redeclaration = false; 1374 if (D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_typedef) { 1375 New = ActOnTypedefDeclarator(S, D, DC, R, LastDeclarator, PrevDecl, 1376 InvalidDecl, Redeclaration); 1377 } else if (R.getTypePtr()->isFunctionType()) { 1378 New = ActOnFunctionDeclarator(S, D, DC, R, LastDeclarator, PrevDecl, 1379 IsFunctionDefinition, InvalidDecl, 1380 Redeclaration); 1381 } else { 1382 New = ActOnVariableDeclarator(S, D, DC, R, LastDeclarator, PrevDecl, 1383 InvalidDecl, Redeclaration); 1384 } 1385 1386 if (New == 0) 1387 return 0; 1388 1389 // Set the lexical context. If the declarator has a C++ scope specifier, the 1390 // lexical context will be different from the semantic context. 1391 New->setLexicalDeclContext(CurContext); 1392 1393 // If this has an identifier and is not an invalid redeclaration, 1394 // add it to the scope stack. 1395 if (Name && !(Redeclaration && InvalidDecl)) 1396 PushOnScopeChains(New, S); 1397 // If any semantic error occurred, mark the decl as invalid. 1398 if (D.getInvalidType() || InvalidDecl) 1399 New->setInvalidDecl(); 1400 1401 return New; 1402} 1403 1404NamedDecl* 1405Sema::ActOnTypedefDeclarator(Scope* S, Declarator& D, DeclContext* DC, 1406 QualType R, Decl* LastDeclarator, 1407 Decl* PrevDecl, bool& InvalidDecl, 1408 bool &Redeclaration) { 1409 // Typedef declarators cannot be qualified (C++ [dcl.meaning]p1). 1410 if (D.getCXXScopeSpec().isSet()) { 1411 Diag(D.getIdentifierLoc(), diag::err_qualified_typedef_declarator) 1412 << D.getCXXScopeSpec().getRange(); 1413 InvalidDecl = true; 1414 // Pretend we didn't see the scope specifier. 1415 DC = 0; 1416 } 1417 1418 // Check that there are no default arguments (C++ only). 1419 if (getLangOptions().CPlusPlus) 1420 CheckExtraCXXDefaultArguments(D); 1421 1422 TypedefDecl *NewTD = ParseTypedefDecl(S, D, R, LastDeclarator); 1423 if (!NewTD) return 0; 1424 1425 // Handle attributes prior to checking for duplicates in MergeVarDecl 1426 ProcessDeclAttributes(NewTD, D); 1427 // Merge the decl with the existing one if appropriate. If the decl is 1428 // in an outer scope, it isn't the same thing. 1429 if (PrevDecl && isDeclInScope(PrevDecl, DC, S)) { 1430 Redeclaration = true; 1431 if (MergeTypeDefDecl(NewTD, PrevDecl)) 1432 InvalidDecl = true; 1433 } 1434 1435 if (S->getFnParent() == 0) { 1436 // C99 6.7.7p2: If a typedef name specifies a variably modified type 1437 // then it shall have block scope. 1438 if (NewTD->getUnderlyingType()->isVariablyModifiedType()) { 1439 if (NewTD->getUnderlyingType()->isVariableArrayType()) 1440 Diag(D.getIdentifierLoc(), diag::err_vla_decl_in_file_scope); 1441 else 1442 Diag(D.getIdentifierLoc(), diag::err_vm_decl_in_file_scope); 1443 1444 InvalidDecl = true; 1445 } 1446 } 1447 return NewTD; 1448} 1449 1450NamedDecl* 1451Sema::ActOnVariableDeclarator(Scope* S, Declarator& D, DeclContext* DC, 1452 QualType R, Decl* LastDeclarator, 1453 Decl* PrevDecl, bool& InvalidDecl, 1454 bool &Redeclaration) { 1455 DeclarationName Name = GetNameForDeclarator(D); 1456 1457 // Check that there are no default arguments (C++ only). 1458 if (getLangOptions().CPlusPlus) 1459 CheckExtraCXXDefaultArguments(D); 1460 1461 if (R.getTypePtr()->isObjCInterfaceType()) { 1462 Diag(D.getIdentifierLoc(), diag::err_statically_allocated_object) 1463 << D.getIdentifier(); 1464 InvalidDecl = true; 1465 } 1466 1467 VarDecl *NewVD; 1468 VarDecl::StorageClass SC; 1469 switch (D.getDeclSpec().getStorageClassSpec()) { 1470 default: assert(0 && "Unknown storage class!"); 1471 case DeclSpec::SCS_unspecified: SC = VarDecl::None; break; 1472 case DeclSpec::SCS_extern: SC = VarDecl::Extern; break; 1473 case DeclSpec::SCS_static: SC = VarDecl::Static; break; 1474 case DeclSpec::SCS_auto: SC = VarDecl::Auto; break; 1475 case DeclSpec::SCS_register: SC = VarDecl::Register; break; 1476 case DeclSpec::SCS_private_extern: SC = VarDecl::PrivateExtern; break; 1477 case DeclSpec::SCS_mutable: 1478 // mutable can only appear on non-static class members, so it's always 1479 // an error here 1480 Diag(D.getIdentifierLoc(), diag::err_mutable_nonmember); 1481 InvalidDecl = true; 1482 SC = VarDecl::None; 1483 break; 1484 } 1485 1486 IdentifierInfo *II = Name.getAsIdentifierInfo(); 1487 if (!II) { 1488 Diag(D.getIdentifierLoc(), diag::err_bad_variable_name) 1489 << Name.getAsString(); 1490 return 0; 1491 } 1492 1493 if (DC->isRecord()) { 1494 // This is a static data member for a C++ class. 1495 NewVD = CXXClassVarDecl::Create(Context, cast<CXXRecordDecl>(DC), 1496 D.getIdentifierLoc(), II, 1497 R); 1498 } else { 1499 bool ThreadSpecified = D.getDeclSpec().isThreadSpecified(); 1500 if (S->getFnParent() == 0) { 1501 // C99 6.9p2: The storage-class specifiers auto and register shall not 1502 // appear in the declaration specifiers in an external declaration. 1503 if (SC == VarDecl::Auto || SC == VarDecl::Register) { 1504 Diag(D.getIdentifierLoc(), diag::err_typecheck_sclass_fscope); 1505 InvalidDecl = true; 1506 } 1507 } 1508 NewVD = VarDecl::Create(Context, DC, D.getIdentifierLoc(), 1509 II, R, SC, 1510 // FIXME: Move to DeclGroup... 1511 D.getDeclSpec().getSourceRange().getBegin()); 1512 NewVD->setThreadSpecified(ThreadSpecified); 1513 } 1514 NewVD->setNextDeclarator(LastDeclarator); 1515 1516 // Handle attributes prior to checking for duplicates in MergeVarDecl 1517 ProcessDeclAttributes(NewVD, D); 1518 1519 // Handle GNU asm-label extension (encoded as an attribute). 1520 if (Expr *E = (Expr*) D.getAsmLabel()) { 1521 // The parser guarantees this is a string. 1522 StringLiteral *SE = cast<StringLiteral>(E); 1523 NewVD->addAttr(new AsmLabelAttr(std::string(SE->getStrData(), 1524 SE->getByteLength()))); 1525 } 1526 1527 // Emit an error if an address space was applied to decl with local storage. 1528 // This includes arrays of objects with address space qualifiers, but not 1529 // automatic variables that point to other address spaces. 1530 // ISO/IEC TR 18037 S5.1.2 1531 if (NewVD->hasLocalStorage() && (NewVD->getType().getAddressSpace() != 0)) { 1532 Diag(D.getIdentifierLoc(), diag::err_as_qualified_auto_decl); 1533 InvalidDecl = true; 1534 } 1535 // Merge the decl with the existing one if appropriate. If the decl is 1536 // in an outer scope, it isn't the same thing. 1537 if (PrevDecl && isDeclInScope(PrevDecl, DC, S)) { 1538 if (isa<FieldDecl>(PrevDecl) && D.getCXXScopeSpec().isSet()) { 1539 // The user tried to define a non-static data member 1540 // out-of-line (C++ [dcl.meaning]p1). 1541 Diag(NewVD->getLocation(), diag::err_nonstatic_member_out_of_line) 1542 << D.getCXXScopeSpec().getRange(); 1543 NewVD->Destroy(Context); 1544 return 0; 1545 } 1546 1547 Redeclaration = true; 1548 if (MergeVarDecl(NewVD, PrevDecl)) 1549 InvalidDecl = true; 1550 1551 if (D.getCXXScopeSpec().isSet()) { 1552 // No previous declaration in the qualifying scope. 1553 Diag(D.getIdentifierLoc(), diag::err_typecheck_no_member) 1554 << Name << D.getCXXScopeSpec().getRange(); 1555 InvalidDecl = true; 1556 } 1557 } 1558 return NewVD; 1559} 1560 1561NamedDecl* 1562Sema::ActOnFunctionDeclarator(Scope* S, Declarator& D, DeclContext* DC, 1563 QualType R, Decl *LastDeclarator, 1564 Decl* PrevDecl, bool IsFunctionDefinition, 1565 bool& InvalidDecl, bool &Redeclaration) { 1566 assert(R.getTypePtr()->isFunctionType()); 1567 1568 DeclarationName Name = GetNameForDeclarator(D); 1569 FunctionDecl::StorageClass SC = FunctionDecl::None; 1570 switch (D.getDeclSpec().getStorageClassSpec()) { 1571 default: assert(0 && "Unknown storage class!"); 1572 case DeclSpec::SCS_auto: 1573 case DeclSpec::SCS_register: 1574 case DeclSpec::SCS_mutable: 1575 Diag(D.getIdentifierLoc(), diag::err_typecheck_sclass_func); 1576 InvalidDecl = true; 1577 break; 1578 case DeclSpec::SCS_unspecified: SC = FunctionDecl::None; break; 1579 case DeclSpec::SCS_extern: SC = FunctionDecl::Extern; break; 1580 case DeclSpec::SCS_static: SC = FunctionDecl::Static; break; 1581 case DeclSpec::SCS_private_extern: SC = FunctionDecl::PrivateExtern;break; 1582 } 1583 1584 bool isInline = D.getDeclSpec().isInlineSpecified(); 1585 // bool isVirtual = D.getDeclSpec().isVirtualSpecified(); 1586 bool isExplicit = D.getDeclSpec().isExplicitSpecified(); 1587 1588 FunctionDecl *NewFD; 1589 if (D.getKind() == Declarator::DK_Constructor) { 1590 // This is a C++ constructor declaration. 1591 assert(DC->isRecord() && 1592 "Constructors can only be declared in a member context"); 1593 1594 InvalidDecl = InvalidDecl || CheckConstructorDeclarator(D, R, SC); 1595 1596 // Create the new declaration 1597 NewFD = CXXConstructorDecl::Create(Context, 1598 cast<CXXRecordDecl>(DC), 1599 D.getIdentifierLoc(), Name, R, 1600 isExplicit, isInline, 1601 /*isImplicitlyDeclared=*/false); 1602 1603 if (InvalidDecl) 1604 NewFD->setInvalidDecl(); 1605 } else if (D.getKind() == Declarator::DK_Destructor) { 1606 // This is a C++ destructor declaration. 1607 if (DC->isRecord()) { 1608 InvalidDecl = InvalidDecl || CheckDestructorDeclarator(D, R, SC); 1609 1610 NewFD = CXXDestructorDecl::Create(Context, 1611 cast<CXXRecordDecl>(DC), 1612 D.getIdentifierLoc(), Name, R, 1613 isInline, 1614 /*isImplicitlyDeclared=*/false); 1615 1616 if (InvalidDecl) 1617 NewFD->setInvalidDecl(); 1618 } else { 1619 Diag(D.getIdentifierLoc(), diag::err_destructor_not_member); 1620 1621 // Create a FunctionDecl to satisfy the function definition parsing 1622 // code path. 1623 NewFD = FunctionDecl::Create(Context, DC, D.getIdentifierLoc(), 1624 Name, R, SC, isInline, 1625 // FIXME: Move to DeclGroup... 1626 D.getDeclSpec().getSourceRange().getBegin()); 1627 InvalidDecl = true; 1628 NewFD->setInvalidDecl(); 1629 } 1630 } else if (D.getKind() == Declarator::DK_Conversion) { 1631 if (!DC->isRecord()) { 1632 Diag(D.getIdentifierLoc(), 1633 diag::err_conv_function_not_member); 1634 return 0; 1635 } else { 1636 InvalidDecl = InvalidDecl || CheckConversionDeclarator(D, R, SC); 1637 1638 NewFD = CXXConversionDecl::Create(Context, cast<CXXRecordDecl>(DC), 1639 D.getIdentifierLoc(), Name, R, 1640 isInline, isExplicit); 1641 1642 if (InvalidDecl) 1643 NewFD->setInvalidDecl(); 1644 } 1645 } else if (DC->isRecord()) { 1646 // This is a C++ method declaration. 1647 NewFD = CXXMethodDecl::Create(Context, cast<CXXRecordDecl>(DC), 1648 D.getIdentifierLoc(), Name, R, 1649 (SC == FunctionDecl::Static), isInline); 1650 } else { 1651 NewFD = FunctionDecl::Create(Context, DC, 1652 D.getIdentifierLoc(), 1653 Name, R, SC, isInline, 1654 // FIXME: Move to DeclGroup... 1655 D.getDeclSpec().getSourceRange().getBegin()); 1656 } 1657 NewFD->setNextDeclarator(LastDeclarator); 1658 1659 // Set the lexical context. If the declarator has a C++ 1660 // scope specifier, the lexical context will be different 1661 // from the semantic context. 1662 NewFD->setLexicalDeclContext(CurContext); 1663 1664 // Handle GNU asm-label extension (encoded as an attribute). 1665 if (Expr *E = (Expr*) D.getAsmLabel()) { 1666 // The parser guarantees this is a string. 1667 StringLiteral *SE = cast<StringLiteral>(E); 1668 NewFD->addAttr(new AsmLabelAttr(std::string(SE->getStrData(), 1669 SE->getByteLength()))); 1670 } 1671 1672 // Copy the parameter declarations from the declarator D to 1673 // the function declaration NewFD, if they are available. 1674 if (D.getNumTypeObjects() > 0) { 1675 DeclaratorChunk::FunctionTypeInfo &FTI = D.getTypeObject(0).Fun; 1676 1677 // Create Decl objects for each parameter, adding them to the 1678 // FunctionDecl. 1679 llvm::SmallVector<ParmVarDecl*, 16> Params; 1680 1681 // Check for C99 6.7.5.3p10 - foo(void) is a non-varargs 1682 // function that takes no arguments, not a function that takes a 1683 // single void argument. 1684 // We let through "const void" here because Sema::GetTypeForDeclarator 1685 // already checks for that case. 1686 if (FTI.NumArgs == 1 && !FTI.isVariadic && FTI.ArgInfo[0].Ident == 0 && 1687 FTI.ArgInfo[0].Param && 1688 ((ParmVarDecl*)FTI.ArgInfo[0].Param)->getType()->isVoidType()) { 1689 // empty arg list, don't push any params. 1690 ParmVarDecl *Param = (ParmVarDecl*)FTI.ArgInfo[0].Param; 1691 1692 // In C++, the empty parameter-type-list must be spelled "void"; a 1693 // typedef of void is not permitted. 1694 if (getLangOptions().CPlusPlus && 1695 Param->getType().getUnqualifiedType() != Context.VoidTy) { 1696 Diag(Param->getLocation(), diag::ext_param_typedef_of_void); 1697 } 1698 } else if (FTI.NumArgs > 0 && FTI.ArgInfo[0].Param != 0) { 1699 for (unsigned i = 0, e = FTI.NumArgs; i != e; ++i) 1700 Params.push_back((ParmVarDecl *)FTI.ArgInfo[i].Param); 1701 } 1702 1703 NewFD->setParams(Context, &Params[0], Params.size()); 1704 } else if (R->getAsTypedefType()) { 1705 // When we're declaring a function with a typedef, as in the 1706 // following example, we'll need to synthesize (unnamed) 1707 // parameters for use in the declaration. 1708 // 1709 // @code 1710 // typedef void fn(int); 1711 // fn f; 1712 // @endcode 1713 const FunctionTypeProto *FT = R->getAsFunctionTypeProto(); 1714 if (!FT) { 1715 // This is a typedef of a function with no prototype, so we 1716 // don't need to do anything. 1717 } else if ((FT->getNumArgs() == 0) || 1718 (FT->getNumArgs() == 1 && !FT->isVariadic() && 1719 FT->getArgType(0)->isVoidType())) { 1720 // This is a zero-argument function. We don't need to do anything. 1721 } else { 1722 // Synthesize a parameter for each argument type. 1723 llvm::SmallVector<ParmVarDecl*, 16> Params; 1724 for (FunctionTypeProto::arg_type_iterator ArgType = FT->arg_type_begin(); 1725 ArgType != FT->arg_type_end(); ++ArgType) { 1726 ParmVarDecl *Param = ParmVarDecl::Create(Context, DC, 1727 SourceLocation(), 0, 1728 *ArgType, VarDecl::None, 1729 0); 1730 Param->setImplicit(); 1731 Params.push_back(Param); 1732 } 1733 1734 NewFD->setParams(Context, &Params[0], Params.size()); 1735 } 1736 } 1737 1738 if (CXXConstructorDecl *Constructor = dyn_cast<CXXConstructorDecl>(NewFD)) 1739 InvalidDecl = InvalidDecl || CheckConstructor(Constructor); 1740 else if (isa<CXXDestructorDecl>(NewFD)) { 1741 CXXRecordDecl *Record = cast<CXXRecordDecl>(NewFD->getParent()); 1742 Record->setUserDeclaredDestructor(true); 1743 // C++ [class]p4: A POD-struct is an aggregate class that has [...] no 1744 // user-defined destructor. 1745 Record->setPOD(false); 1746 } else if (CXXConversionDecl *Conversion = 1747 dyn_cast<CXXConversionDecl>(NewFD)) 1748 ActOnConversionDeclarator(Conversion); 1749 1750 // Extra checking for C++ overloaded operators (C++ [over.oper]). 1751 if (NewFD->isOverloadedOperator() && 1752 CheckOverloadedOperatorDeclaration(NewFD)) 1753 NewFD->setInvalidDecl(); 1754 1755 // Merge the decl with the existing one if appropriate. Since C functions 1756 // are in a flat namespace, make sure we consider decls in outer scopes. 1757 bool OverloadableAttrRequired = false; 1758 if (PrevDecl && 1759 (!getLangOptions().CPlusPlus||isDeclInScope(PrevDecl, DC, S))) { 1760 // Determine whether NewFD is an overload of PrevDecl or 1761 // a declaration that requires merging. If it's an overload, 1762 // there's no more work to do here; we'll just add the new 1763 // function to the scope. 1764 OverloadedFunctionDecl::function_iterator MatchedDecl; 1765 1766 if (!getLangOptions().CPlusPlus && 1767 AllowOverloadingOfFunction(PrevDecl, Context)) 1768 OverloadableAttrRequired = true; 1769 1770 if (!AllowOverloadingOfFunction(PrevDecl, Context) || 1771 !IsOverload(NewFD, PrevDecl, MatchedDecl)) { 1772 Redeclaration = true; 1773 Decl *OldDecl = PrevDecl; 1774 1775 // If PrevDecl was an overloaded function, extract the 1776 // FunctionDecl that matched. 1777 if (isa<OverloadedFunctionDecl>(PrevDecl)) 1778 OldDecl = *MatchedDecl; 1779 1780 // NewFD and PrevDecl represent declarations that need to be 1781 // merged. 1782 if (MergeFunctionDecl(NewFD, OldDecl)) 1783 InvalidDecl = true; 1784 1785 if (!InvalidDecl) { 1786 NewFD->setPreviousDeclaration(cast<FunctionDecl>(OldDecl)); 1787 1788 // An out-of-line member function declaration must also be a 1789 // definition (C++ [dcl.meaning]p1). 1790 if (!IsFunctionDefinition && D.getCXXScopeSpec().isSet() && 1791 !InvalidDecl) { 1792 Diag(NewFD->getLocation(), diag::err_out_of_line_declaration) 1793 << D.getCXXScopeSpec().getRange(); 1794 NewFD->setInvalidDecl(); 1795 } 1796 } 1797 } 1798 } 1799 1800 if (D.getCXXScopeSpec().isSet() && 1801 (!PrevDecl || !Redeclaration)) { 1802 // The user tried to provide an out-of-line definition for a 1803 // function that is a member of a class or namespace, but there 1804 // was no such member function declared (C++ [class.mfct]p2, 1805 // C++ [namespace.memdef]p2). For example: 1806 // 1807 // class X { 1808 // void f() const; 1809 // }; 1810 // 1811 // void X::f() { } // ill-formed 1812 // 1813 // Complain about this problem, and attempt to suggest close 1814 // matches (e.g., those that differ only in cv-qualifiers and 1815 // whether the parameter types are references). 1816 Diag(D.getIdentifierLoc(), diag::err_member_def_does_not_match) 1817 << cast<NamedDecl>(DC) << D.getCXXScopeSpec().getRange(); 1818 InvalidDecl = true; 1819 1820 LookupResult Prev = LookupQualifiedName(DC, Name, LookupOrdinaryName, 1821 true); 1822 assert(!Prev.isAmbiguous() && 1823 "Cannot have an ambiguity in previous-declaration lookup"); 1824 for (LookupResult::iterator Func = Prev.begin(), FuncEnd = Prev.end(); 1825 Func != FuncEnd; ++Func) { 1826 if (isa<FunctionDecl>(*Func) && 1827 isNearlyMatchingFunction(Context, cast<FunctionDecl>(*Func), NewFD)) 1828 Diag((*Func)->getLocation(), diag::note_member_def_close_match); 1829 } 1830 1831 PrevDecl = 0; 1832 } 1833 1834 // Handle attributes. We need to have merged decls when handling attributes 1835 // (for example to check for conflicts, etc). 1836 ProcessDeclAttributes(NewFD, D); 1837 AddKnownFunctionAttributes(NewFD); 1838 1839 if (OverloadableAttrRequired && !NewFD->getAttr<OverloadableAttr>()) { 1840 // If a function name is overloadable in C, then every function 1841 // with that name must be marked "overloadable". 1842 Diag(NewFD->getLocation(), diag::err_attribute_overloadable_missing) 1843 << Redeclaration << NewFD; 1844 if (PrevDecl) 1845 Diag(PrevDecl->getLocation(), 1846 diag::note_attribute_overloadable_prev_overload); 1847 NewFD->addAttr(new OverloadableAttr); 1848 } 1849 1850 if (getLangOptions().CPlusPlus) { 1851 // In C++, check default arguments now that we have merged decls. Unless 1852 // the lexical context is the class, because in this case this is done 1853 // during delayed parsing anyway. 1854 if (!CurContext->isRecord()) 1855 CheckCXXDefaultArguments(NewFD); 1856 1857 // An out-of-line member function declaration must also be a 1858 // definition (C++ [dcl.meaning]p1). 1859 if (!IsFunctionDefinition && D.getCXXScopeSpec().isSet() && !InvalidDecl) { 1860 Diag(NewFD->getLocation(), diag::err_out_of_line_declaration) 1861 << D.getCXXScopeSpec().getRange(); 1862 InvalidDecl = true; 1863 } 1864 } 1865 return NewFD; 1866} 1867 1868void Sema::InitializerElementNotConstant(const Expr *Init) { 1869 Diag(Init->getExprLoc(), diag::err_init_element_not_constant) 1870 << Init->getSourceRange(); 1871} 1872 1873bool Sema::CheckAddressConstantExpressionLValue(const Expr* Init) { 1874 switch (Init->getStmtClass()) { 1875 default: 1876 InitializerElementNotConstant(Init); 1877 return true; 1878 case Expr::ParenExprClass: { 1879 const ParenExpr* PE = cast<ParenExpr>(Init); 1880 return CheckAddressConstantExpressionLValue(PE->getSubExpr()); 1881 } 1882 case Expr::CompoundLiteralExprClass: 1883 return cast<CompoundLiteralExpr>(Init)->isFileScope(); 1884 case Expr::DeclRefExprClass: 1885 case Expr::QualifiedDeclRefExprClass: { 1886 const Decl *D = cast<DeclRefExpr>(Init)->getDecl(); 1887 if (const VarDecl *VD = dyn_cast<VarDecl>(D)) { 1888 if (VD->hasGlobalStorage()) 1889 return false; 1890 InitializerElementNotConstant(Init); 1891 return true; 1892 } 1893 if (isa<FunctionDecl>(D)) 1894 return false; 1895 InitializerElementNotConstant(Init); 1896 return true; 1897 } 1898 case Expr::MemberExprClass: { 1899 const MemberExpr *M = cast<MemberExpr>(Init); 1900 if (M->isArrow()) 1901 return CheckAddressConstantExpression(M->getBase()); 1902 return CheckAddressConstantExpressionLValue(M->getBase()); 1903 } 1904 case Expr::ArraySubscriptExprClass: { 1905 // FIXME: Should we pedwarn for "x[0+0]" (where x is a pointer)? 1906 const ArraySubscriptExpr *ASE = cast<ArraySubscriptExpr>(Init); 1907 return CheckAddressConstantExpression(ASE->getBase()) || 1908 CheckArithmeticConstantExpression(ASE->getIdx()); 1909 } 1910 case Expr::StringLiteralClass: 1911 case Expr::PredefinedExprClass: 1912 return false; 1913 case Expr::UnaryOperatorClass: { 1914 const UnaryOperator *Exp = cast<UnaryOperator>(Init); 1915 1916 // C99 6.6p9 1917 if (Exp->getOpcode() == UnaryOperator::Deref) 1918 return CheckAddressConstantExpression(Exp->getSubExpr()); 1919 1920 InitializerElementNotConstant(Init); 1921 return true; 1922 } 1923 } 1924} 1925 1926bool Sema::CheckAddressConstantExpression(const Expr* Init) { 1927 switch (Init->getStmtClass()) { 1928 default: 1929 InitializerElementNotConstant(Init); 1930 return true; 1931 case Expr::ParenExprClass: 1932 return CheckAddressConstantExpression(cast<ParenExpr>(Init)->getSubExpr()); 1933 case Expr::StringLiteralClass: 1934 case Expr::ObjCStringLiteralClass: 1935 return false; 1936 case Expr::CallExprClass: 1937 case Expr::CXXOperatorCallExprClass: 1938 // __builtin___CFStringMakeConstantString is a valid constant l-value. 1939 if (cast<CallExpr>(Init)->isBuiltinCall(Context) == 1940 Builtin::BI__builtin___CFStringMakeConstantString) 1941 return false; 1942 1943 InitializerElementNotConstant(Init); 1944 return true; 1945 1946 case Expr::UnaryOperatorClass: { 1947 const UnaryOperator *Exp = cast<UnaryOperator>(Init); 1948 1949 // C99 6.6p9 1950 if (Exp->getOpcode() == UnaryOperator::AddrOf) 1951 return CheckAddressConstantExpressionLValue(Exp->getSubExpr()); 1952 1953 if (Exp->getOpcode() == UnaryOperator::Extension) 1954 return CheckAddressConstantExpression(Exp->getSubExpr()); 1955 1956 InitializerElementNotConstant(Init); 1957 return true; 1958 } 1959 case Expr::BinaryOperatorClass: { 1960 // FIXME: Should we pedwarn for expressions like "a + 1 + 2"? 1961 const BinaryOperator *Exp = cast<BinaryOperator>(Init); 1962 1963 Expr *PExp = Exp->getLHS(); 1964 Expr *IExp = Exp->getRHS(); 1965 if (IExp->getType()->isPointerType()) 1966 std::swap(PExp, IExp); 1967 1968 // FIXME: Should we pedwarn if IExp isn't an integer constant expression? 1969 return CheckAddressConstantExpression(PExp) || 1970 CheckArithmeticConstantExpression(IExp); 1971 } 1972 case Expr::ImplicitCastExprClass: 1973 case Expr::CStyleCastExprClass: { 1974 const Expr* SubExpr = cast<CastExpr>(Init)->getSubExpr(); 1975 if (Init->getStmtClass() == Expr::ImplicitCastExprClass) { 1976 // Check for implicit promotion 1977 if (SubExpr->getType()->isFunctionType() || 1978 SubExpr->getType()->isArrayType()) 1979 return CheckAddressConstantExpressionLValue(SubExpr); 1980 } 1981 1982 // Check for pointer->pointer cast 1983 if (SubExpr->getType()->isPointerType()) 1984 return CheckAddressConstantExpression(SubExpr); 1985 1986 if (SubExpr->getType()->isIntegralType()) { 1987 // Check for the special-case of a pointer->int->pointer cast; 1988 // this isn't standard, but some code requires it. See 1989 // PR2720 for an example. 1990 if (const CastExpr* SubCast = dyn_cast<CastExpr>(SubExpr)) { 1991 if (SubCast->getSubExpr()->getType()->isPointerType()) { 1992 unsigned IntWidth = Context.getIntWidth(SubCast->getType()); 1993 unsigned PointerWidth = Context.getTypeSize(Context.VoidPtrTy); 1994 if (IntWidth >= PointerWidth) { 1995 return CheckAddressConstantExpression(SubCast->getSubExpr()); 1996 } 1997 } 1998 } 1999 } 2000 if (SubExpr->getType()->isArithmeticType()) { 2001 return CheckArithmeticConstantExpression(SubExpr); 2002 } 2003 2004 InitializerElementNotConstant(Init); 2005 return true; 2006 } 2007 case Expr::ConditionalOperatorClass: { 2008 // FIXME: Should we pedwarn here? 2009 const ConditionalOperator *Exp = cast<ConditionalOperator>(Init); 2010 if (!Exp->getCond()->getType()->isArithmeticType()) { 2011 InitializerElementNotConstant(Init); 2012 return true; 2013 } 2014 if (CheckArithmeticConstantExpression(Exp->getCond())) 2015 return true; 2016 if (Exp->getLHS() && 2017 CheckAddressConstantExpression(Exp->getLHS())) 2018 return true; 2019 return CheckAddressConstantExpression(Exp->getRHS()); 2020 } 2021 case Expr::AddrLabelExprClass: 2022 return false; 2023 } 2024} 2025 2026static const Expr* FindExpressionBaseAddress(const Expr* E); 2027 2028static const Expr* FindExpressionBaseAddressLValue(const Expr* E) { 2029 switch (E->getStmtClass()) { 2030 default: 2031 return E; 2032 case Expr::ParenExprClass: { 2033 const ParenExpr* PE = cast<ParenExpr>(E); 2034 return FindExpressionBaseAddressLValue(PE->getSubExpr()); 2035 } 2036 case Expr::MemberExprClass: { 2037 const MemberExpr *M = cast<MemberExpr>(E); 2038 if (M->isArrow()) 2039 return FindExpressionBaseAddress(M->getBase()); 2040 return FindExpressionBaseAddressLValue(M->getBase()); 2041 } 2042 case Expr::ArraySubscriptExprClass: { 2043 const ArraySubscriptExpr *ASE = cast<ArraySubscriptExpr>(E); 2044 return FindExpressionBaseAddress(ASE->getBase()); 2045 } 2046 case Expr::UnaryOperatorClass: { 2047 const UnaryOperator *Exp = cast<UnaryOperator>(E); 2048 2049 if (Exp->getOpcode() == UnaryOperator::Deref) 2050 return FindExpressionBaseAddress(Exp->getSubExpr()); 2051 2052 return E; 2053 } 2054 } 2055} 2056 2057static const Expr* FindExpressionBaseAddress(const Expr* E) { 2058 switch (E->getStmtClass()) { 2059 default: 2060 return E; 2061 case Expr::ParenExprClass: { 2062 const ParenExpr* PE = cast<ParenExpr>(E); 2063 return FindExpressionBaseAddress(PE->getSubExpr()); 2064 } 2065 case Expr::UnaryOperatorClass: { 2066 const UnaryOperator *Exp = cast<UnaryOperator>(E); 2067 2068 // C99 6.6p9 2069 if (Exp->getOpcode() == UnaryOperator::AddrOf) 2070 return FindExpressionBaseAddressLValue(Exp->getSubExpr()); 2071 2072 if (Exp->getOpcode() == UnaryOperator::Extension) 2073 return FindExpressionBaseAddress(Exp->getSubExpr()); 2074 2075 return E; 2076 } 2077 case Expr::BinaryOperatorClass: { 2078 const BinaryOperator *Exp = cast<BinaryOperator>(E); 2079 2080 Expr *PExp = Exp->getLHS(); 2081 Expr *IExp = Exp->getRHS(); 2082 if (IExp->getType()->isPointerType()) 2083 std::swap(PExp, IExp); 2084 2085 return FindExpressionBaseAddress(PExp); 2086 } 2087 case Expr::ImplicitCastExprClass: { 2088 const Expr* SubExpr = cast<ImplicitCastExpr>(E)->getSubExpr(); 2089 2090 // Check for implicit promotion 2091 if (SubExpr->getType()->isFunctionType() || 2092 SubExpr->getType()->isArrayType()) 2093 return FindExpressionBaseAddressLValue(SubExpr); 2094 2095 // Check for pointer->pointer cast 2096 if (SubExpr->getType()->isPointerType()) 2097 return FindExpressionBaseAddress(SubExpr); 2098 2099 // We assume that we have an arithmetic expression here; 2100 // if we don't, we'll figure it out later 2101 return 0; 2102 } 2103 case Expr::CStyleCastExprClass: { 2104 const Expr* SubExpr = cast<CastExpr>(E)->getSubExpr(); 2105 2106 // Check for pointer->pointer cast 2107 if (SubExpr->getType()->isPointerType()) 2108 return FindExpressionBaseAddress(SubExpr); 2109 2110 // We assume that we have an arithmetic expression here; 2111 // if we don't, we'll figure it out later 2112 return 0; 2113 } 2114 } 2115} 2116 2117bool Sema::CheckArithmeticConstantExpression(const Expr* Init) { 2118 switch (Init->getStmtClass()) { 2119 default: 2120 InitializerElementNotConstant(Init); 2121 return true; 2122 case Expr::ParenExprClass: { 2123 const ParenExpr* PE = cast<ParenExpr>(Init); 2124 return CheckArithmeticConstantExpression(PE->getSubExpr()); 2125 } 2126 case Expr::FloatingLiteralClass: 2127 case Expr::IntegerLiteralClass: 2128 case Expr::CharacterLiteralClass: 2129 case Expr::ImaginaryLiteralClass: 2130 case Expr::TypesCompatibleExprClass: 2131 case Expr::CXXBoolLiteralExprClass: 2132 return false; 2133 case Expr::CallExprClass: 2134 case Expr::CXXOperatorCallExprClass: { 2135 const CallExpr *CE = cast<CallExpr>(Init); 2136 2137 // Allow any constant foldable calls to builtins. 2138 if (CE->isBuiltinCall(Context) && CE->isEvaluatable(Context)) 2139 return false; 2140 2141 InitializerElementNotConstant(Init); 2142 return true; 2143 } 2144 case Expr::DeclRefExprClass: 2145 case Expr::QualifiedDeclRefExprClass: { 2146 const Decl *D = cast<DeclRefExpr>(Init)->getDecl(); 2147 if (isa<EnumConstantDecl>(D)) 2148 return false; 2149 InitializerElementNotConstant(Init); 2150 return true; 2151 } 2152 case Expr::CompoundLiteralExprClass: 2153 // Allow "(vector type){2,4}"; normal C constraints don't allow this, 2154 // but vectors are allowed to be magic. 2155 if (Init->getType()->isVectorType()) 2156 return false; 2157 InitializerElementNotConstant(Init); 2158 return true; 2159 case Expr::UnaryOperatorClass: { 2160 const UnaryOperator *Exp = cast<UnaryOperator>(Init); 2161 2162 switch (Exp->getOpcode()) { 2163 // Address, indirect, pre/post inc/dec, etc are not valid constant exprs. 2164 // See C99 6.6p3. 2165 default: 2166 InitializerElementNotConstant(Init); 2167 return true; 2168 case UnaryOperator::OffsetOf: 2169 if (Exp->getSubExpr()->getType()->isConstantSizeType()) 2170 return false; 2171 InitializerElementNotConstant(Init); 2172 return true; 2173 case UnaryOperator::Extension: 2174 case UnaryOperator::LNot: 2175 case UnaryOperator::Plus: 2176 case UnaryOperator::Minus: 2177 case UnaryOperator::Not: 2178 return CheckArithmeticConstantExpression(Exp->getSubExpr()); 2179 } 2180 } 2181 case Expr::SizeOfAlignOfExprClass: { 2182 const SizeOfAlignOfExpr *Exp = cast<SizeOfAlignOfExpr>(Init); 2183 // Special check for void types, which are allowed as an extension 2184 if (Exp->getTypeOfArgument()->isVoidType()) 2185 return false; 2186 // alignof always evaluates to a constant. 2187 // FIXME: is sizeof(int[3.0]) a constant expression? 2188 if (Exp->isSizeOf() && !Exp->getTypeOfArgument()->isConstantSizeType()) { 2189 InitializerElementNotConstant(Init); 2190 return true; 2191 } 2192 return false; 2193 } 2194 case Expr::BinaryOperatorClass: { 2195 const BinaryOperator *Exp = cast<BinaryOperator>(Init); 2196 2197 if (Exp->getLHS()->getType()->isArithmeticType() && 2198 Exp->getRHS()->getType()->isArithmeticType()) { 2199 return CheckArithmeticConstantExpression(Exp->getLHS()) || 2200 CheckArithmeticConstantExpression(Exp->getRHS()); 2201 } 2202 2203 if (Exp->getLHS()->getType()->isPointerType() && 2204 Exp->getRHS()->getType()->isPointerType()) { 2205 const Expr* LHSBase = FindExpressionBaseAddress(Exp->getLHS()); 2206 const Expr* RHSBase = FindExpressionBaseAddress(Exp->getRHS()); 2207 2208 // Only allow a null (constant integer) base; we could 2209 // allow some additional cases if necessary, but this 2210 // is sufficient to cover offsetof-like constructs. 2211 if (!LHSBase && !RHSBase) { 2212 return CheckAddressConstantExpression(Exp->getLHS()) || 2213 CheckAddressConstantExpression(Exp->getRHS()); 2214 } 2215 } 2216 2217 InitializerElementNotConstant(Init); 2218 return true; 2219 } 2220 case Expr::ImplicitCastExprClass: 2221 case Expr::CStyleCastExprClass: { 2222 const CastExpr *CE = cast<CastExpr>(Init); 2223 const Expr *SubExpr = CE->getSubExpr(); 2224 2225 if (SubExpr->getType()->isArithmeticType()) 2226 return CheckArithmeticConstantExpression(SubExpr); 2227 2228 if (SubExpr->getType()->isPointerType()) { 2229 const Expr* Base = FindExpressionBaseAddress(SubExpr); 2230 if (Base) { 2231 // the cast is only valid if done to a wide enough type 2232 if (Context.getTypeSize(CE->getType()) >= 2233 Context.getTypeSize(SubExpr->getType())) 2234 return false; 2235 } else { 2236 // If the pointer has a null base, this is an offsetof-like construct 2237 return CheckAddressConstantExpression(SubExpr); 2238 } 2239 } 2240 2241 InitializerElementNotConstant(Init); 2242 return true; 2243 } 2244 case Expr::ConditionalOperatorClass: { 2245 const ConditionalOperator *Exp = cast<ConditionalOperator>(Init); 2246 2247 // If GNU extensions are disabled, we require all operands to be arithmetic 2248 // constant expressions. 2249 if (getLangOptions().NoExtensions) { 2250 return CheckArithmeticConstantExpression(Exp->getCond()) || 2251 (Exp->getLHS() && CheckArithmeticConstantExpression(Exp->getLHS())) || 2252 CheckArithmeticConstantExpression(Exp->getRHS()); 2253 } 2254 2255 // Otherwise, we have to emulate some of the behavior of fold here. 2256 // Basically GCC treats things like "4 ? 1 : somefunc()" as a constant 2257 // because it can constant fold things away. To retain compatibility with 2258 // GCC code, we see if we can fold the condition to a constant (which we 2259 // should always be able to do in theory). If so, we only require the 2260 // specified arm of the conditional to be a constant. This is a horrible 2261 // hack, but is require by real world code that uses __builtin_constant_p. 2262 Expr::EvalResult EvalResult; 2263 if (!Exp->getCond()->Evaluate(EvalResult, Context) || 2264 EvalResult.HasSideEffects) { 2265 // If Evaluate couldn't fold it, CheckArithmeticConstantExpression 2266 // won't be able to either. Use it to emit the diagnostic though. 2267 bool Res = CheckArithmeticConstantExpression(Exp->getCond()); 2268 assert(Res && "Evaluate couldn't evaluate this constant?"); 2269 return Res; 2270 } 2271 2272 // Verify that the side following the condition is also a constant. 2273 const Expr *TrueSide = Exp->getLHS(), *FalseSide = Exp->getRHS(); 2274 if (EvalResult.Val.getInt() == 0) 2275 std::swap(TrueSide, FalseSide); 2276 2277 if (TrueSide && CheckArithmeticConstantExpression(TrueSide)) 2278 return true; 2279 2280 // Okay, the evaluated side evaluates to a constant, so we accept this. 2281 // Check to see if the other side is obviously not a constant. If so, 2282 // emit a warning that this is a GNU extension. 2283 if (FalseSide && !FalseSide->isEvaluatable(Context)) 2284 Diag(Init->getExprLoc(), 2285 diag::ext_typecheck_expression_not_constant_but_accepted) 2286 << FalseSide->getSourceRange(); 2287 return false; 2288 } 2289 } 2290} 2291 2292bool Sema::CheckForConstantInitializer(Expr *Init, QualType DclT) { 2293 if (DesignatedInitExpr *DIE = dyn_cast<DesignatedInitExpr>(Init)) 2294 Init = DIE->getInit(); 2295 2296 Init = Init->IgnoreParens(); 2297 2298 if (Init->isEvaluatable(Context)) 2299 return false; 2300 2301 // Look through CXXDefaultArgExprs; they have no meaning in this context. 2302 if (CXXDefaultArgExpr* DAE = dyn_cast<CXXDefaultArgExpr>(Init)) 2303 return CheckForConstantInitializer(DAE->getExpr(), DclT); 2304 2305 if (CompoundLiteralExpr *e = dyn_cast<CompoundLiteralExpr>(Init)) 2306 return CheckForConstantInitializer(e->getInitializer(), DclT); 2307 2308 if (isa<ImplicitValueInitExpr>(Init)) { 2309 // FIXME: In C++, check for non-POD types. 2310 return false; 2311 } 2312 2313 if (InitListExpr *Exp = dyn_cast<InitListExpr>(Init)) { 2314 unsigned numInits = Exp->getNumInits(); 2315 for (unsigned i = 0; i < numInits; i++) { 2316 // FIXME: Need to get the type of the declaration for C++, 2317 // because it could be a reference? 2318 2319 if (CheckForConstantInitializer(Exp->getInit(i), 2320 Exp->getInit(i)->getType())) 2321 return true; 2322 } 2323 return false; 2324 } 2325 2326 // FIXME: We can probably remove some of this code below, now that 2327 // Expr::Evaluate is doing the heavy lifting for scalars. 2328 2329 if (Init->isNullPointerConstant(Context)) 2330 return false; 2331 if (Init->getType()->isArithmeticType()) { 2332 QualType InitTy = Context.getCanonicalType(Init->getType()) 2333 .getUnqualifiedType(); 2334 if (InitTy == Context.BoolTy) { 2335 // Special handling for pointers implicitly cast to bool; 2336 // (e.g. "_Bool rr = &rr;"). This is only legal at the top level. 2337 if (ImplicitCastExpr* ICE = dyn_cast<ImplicitCastExpr>(Init)) { 2338 Expr* SubE = ICE->getSubExpr(); 2339 if (SubE->getType()->isPointerType() || 2340 SubE->getType()->isArrayType() || 2341 SubE->getType()->isFunctionType()) { 2342 return CheckAddressConstantExpression(Init); 2343 } 2344 } 2345 } else if (InitTy->isIntegralType()) { 2346 Expr* SubE = 0; 2347 if (CastExpr* CE = dyn_cast<CastExpr>(Init)) 2348 SubE = CE->getSubExpr(); 2349 // Special check for pointer cast to int; we allow as an extension 2350 // an address constant cast to an integer if the integer 2351 // is of an appropriate width (this sort of code is apparently used 2352 // in some places). 2353 // FIXME: Add pedwarn? 2354 // FIXME: Don't allow bitfields here! Need the FieldDecl for that. 2355 if (SubE && (SubE->getType()->isPointerType() || 2356 SubE->getType()->isArrayType() || 2357 SubE->getType()->isFunctionType())) { 2358 unsigned IntWidth = Context.getTypeSize(Init->getType()); 2359 unsigned PointerWidth = Context.getTypeSize(Context.VoidPtrTy); 2360 if (IntWidth >= PointerWidth) 2361 return CheckAddressConstantExpression(Init); 2362 } 2363 } 2364 2365 return CheckArithmeticConstantExpression(Init); 2366 } 2367 2368 if (Init->getType()->isPointerType()) 2369 return CheckAddressConstantExpression(Init); 2370 2371 // An array type at the top level that isn't an init-list must 2372 // be a string literal 2373 if (Init->getType()->isArrayType()) 2374 return false; 2375 2376 if (Init->getType()->isFunctionType()) 2377 return false; 2378 2379 // Allow block exprs at top level. 2380 if (Init->getType()->isBlockPointerType()) 2381 return false; 2382 2383 // GCC cast to union extension 2384 // note: the validity of the cast expr is checked by CheckCastTypes() 2385 if (CastExpr *C = dyn_cast<CastExpr>(Init)) { 2386 QualType T = C->getType(); 2387 return T->isUnionType() && CheckForConstantInitializer(C->getSubExpr(), T); 2388 } 2389 2390 InitializerElementNotConstant(Init); 2391 return true; 2392} 2393 2394void Sema::AddInitializerToDecl(DeclTy *dcl, ExprArg init) { 2395 AddInitializerToDecl(dcl, move(init), /*DirectInit=*/false); 2396} 2397 2398/// AddInitializerToDecl - Adds the initializer Init to the 2399/// declaration dcl. If DirectInit is true, this is C++ direct 2400/// initialization rather than copy initialization. 2401void Sema::AddInitializerToDecl(DeclTy *dcl, ExprArg init, bool DirectInit) { 2402 Decl *RealDecl = static_cast<Decl *>(dcl); 2403 Expr *Init = static_cast<Expr *>(init.release()); 2404 assert(Init && "missing initializer"); 2405 2406 // If there is no declaration, there was an error parsing it. Just ignore 2407 // the initializer. 2408 if (RealDecl == 0) { 2409 Init->Destroy(Context); 2410 return; 2411 } 2412 2413 VarDecl *VDecl = dyn_cast<VarDecl>(RealDecl); 2414 if (!VDecl) { 2415 Diag(RealDecl->getLocation(), diag::err_illegal_initializer); 2416 RealDecl->setInvalidDecl(); 2417 return; 2418 } 2419 // Get the decls type and save a reference for later, since 2420 // CheckInitializerTypes may change it. 2421 QualType DclT = VDecl->getType(), SavT = DclT; 2422 if (VDecl->isBlockVarDecl()) { 2423 VarDecl::StorageClass SC = VDecl->getStorageClass(); 2424 if (SC == VarDecl::Extern) { // C99 6.7.8p5 2425 Diag(VDecl->getLocation(), diag::err_block_extern_cant_init); 2426 VDecl->setInvalidDecl(); 2427 } else if (!VDecl->isInvalidDecl()) { 2428 if (CheckInitializerTypes(Init, DclT, VDecl->getLocation(), 2429 VDecl->getDeclName(), DirectInit)) 2430 VDecl->setInvalidDecl(); 2431 2432 // C++ 3.6.2p2, allow dynamic initialization of static initializers. 2433 if (!getLangOptions().CPlusPlus) { 2434 if (SC == VarDecl::Static) // C99 6.7.8p4. 2435 CheckForConstantInitializer(Init, DclT); 2436 } 2437 } 2438 } else if (VDecl->isFileVarDecl()) { 2439 if (VDecl->getStorageClass() == VarDecl::Extern) 2440 Diag(VDecl->getLocation(), diag::warn_extern_init); 2441 if (!VDecl->isInvalidDecl()) 2442 if (CheckInitializerTypes(Init, DclT, VDecl->getLocation(), 2443 VDecl->getDeclName(), DirectInit)) 2444 VDecl->setInvalidDecl(); 2445 2446 // C++ 3.6.2p2, allow dynamic initialization of static initializers. 2447 if (!getLangOptions().CPlusPlus) { 2448 // C99 6.7.8p4. All file scoped initializers need to be constant. 2449 CheckForConstantInitializer(Init, DclT); 2450 } 2451 } 2452 // If the type changed, it means we had an incomplete type that was 2453 // completed by the initializer. For example: 2454 // int ary[] = { 1, 3, 5 }; 2455 // "ary" transitions from a VariableArrayType to a ConstantArrayType. 2456 if (!VDecl->isInvalidDecl() && (DclT != SavT)) { 2457 VDecl->setType(DclT); 2458 Init->setType(DclT); 2459 } 2460 2461 // Attach the initializer to the decl. 2462 VDecl->setInit(Init); 2463 return; 2464} 2465 2466void Sema::ActOnUninitializedDecl(DeclTy *dcl) { 2467 Decl *RealDecl = static_cast<Decl *>(dcl); 2468 2469 // If there is no declaration, there was an error parsing it. Just ignore it. 2470 if (RealDecl == 0) 2471 return; 2472 2473 if (VarDecl *Var = dyn_cast<VarDecl>(RealDecl)) { 2474 QualType Type = Var->getType(); 2475 // C++ [dcl.init.ref]p3: 2476 // The initializer can be omitted for a reference only in a 2477 // parameter declaration (8.3.5), in the declaration of a 2478 // function return type, in the declaration of a class member 2479 // within its class declaration (9.2), and where the extern 2480 // specifier is explicitly used. 2481 if (Type->isReferenceType() && 2482 Var->getStorageClass() != VarDecl::Extern && 2483 Var->getStorageClass() != VarDecl::PrivateExtern) { 2484 Diag(Var->getLocation(), diag::err_reference_var_requires_init) 2485 << Var->getDeclName() 2486 << SourceRange(Var->getLocation(), Var->getLocation()); 2487 Var->setInvalidDecl(); 2488 return; 2489 } 2490 2491 // C++ [dcl.init]p9: 2492 // 2493 // If no initializer is specified for an object, and the object 2494 // is of (possibly cv-qualified) non-POD class type (or array 2495 // thereof), the object shall be default-initialized; if the 2496 // object is of const-qualified type, the underlying class type 2497 // shall have a user-declared default constructor. 2498 if (getLangOptions().CPlusPlus) { 2499 QualType InitType = Type; 2500 if (const ArrayType *Array = Context.getAsArrayType(Type)) 2501 InitType = Array->getElementType(); 2502 if (Var->getStorageClass() != VarDecl::Extern && 2503 Var->getStorageClass() != VarDecl::PrivateExtern && 2504 InitType->isRecordType()) { 2505 const CXXConstructorDecl *Constructor 2506 = PerformInitializationByConstructor(InitType, 0, 0, 2507 Var->getLocation(), 2508 SourceRange(Var->getLocation(), 2509 Var->getLocation()), 2510 Var->getDeclName(), 2511 IK_Default); 2512 if (!Constructor) 2513 Var->setInvalidDecl(); 2514 } 2515 } 2516 2517#if 0 2518 // FIXME: Temporarily disabled because we are not properly parsing 2519 // linkage specifications on declarations, e.g., 2520 // 2521 // extern "C" const CGPoint CGPointerZero; 2522 // 2523 // C++ [dcl.init]p9: 2524 // 2525 // If no initializer is specified for an object, and the 2526 // object is of (possibly cv-qualified) non-POD class type (or 2527 // array thereof), the object shall be default-initialized; if 2528 // the object is of const-qualified type, the underlying class 2529 // type shall have a user-declared default 2530 // constructor. Otherwise, if no initializer is specified for 2531 // an object, the object and its subobjects, if any, have an 2532 // indeterminate initial value; if the object or any of its 2533 // subobjects are of const-qualified type, the program is 2534 // ill-formed. 2535 // 2536 // This isn't technically an error in C, so we don't diagnose it. 2537 // 2538 // FIXME: Actually perform the POD/user-defined default 2539 // constructor check. 2540 if (getLangOptions().CPlusPlus && 2541 Context.getCanonicalType(Type).isConstQualified() && 2542 Var->getStorageClass() != VarDecl::Extern) 2543 Diag(Var->getLocation(), diag::err_const_var_requires_init) 2544 << Var->getName() 2545 << SourceRange(Var->getLocation(), Var->getLocation()); 2546#endif 2547 } 2548} 2549 2550/// The declarators are chained together backwards, reverse the list. 2551Sema::DeclTy *Sema::FinalizeDeclaratorGroup(Scope *S, DeclTy *group) { 2552 // Often we have single declarators, handle them quickly. 2553 Decl *GroupDecl = static_cast<Decl*>(group); 2554 if (GroupDecl == 0) 2555 return 0; 2556 2557 Decl *Group = dyn_cast<Decl>(GroupDecl); 2558 Decl *NewGroup = 0; 2559 if (Group->getNextDeclarator() == 0) 2560 NewGroup = Group; 2561 else { // reverse the list. 2562 while (Group) { 2563 Decl *Next = Group->getNextDeclarator(); 2564 Group->setNextDeclarator(NewGroup); 2565 NewGroup = Group; 2566 Group = Next; 2567 } 2568 } 2569 // Perform semantic analysis that depends on having fully processed both 2570 // the declarator and initializer. 2571 for (Decl *ID = NewGroup; ID; ID = ID->getNextDeclarator()) { 2572 VarDecl *IDecl = dyn_cast<VarDecl>(ID); 2573 if (!IDecl) 2574 continue; 2575 QualType T = IDecl->getType(); 2576 2577 if (T->isVariableArrayType()) { 2578 const VariableArrayType *VAT = Context.getAsVariableArrayType(T); 2579 2580 // FIXME: This won't give the correct result for 2581 // int a[10][n]; 2582 SourceRange SizeRange = VAT->getSizeExpr()->getSourceRange(); 2583 if (IDecl->isFileVarDecl()) { 2584 Diag(IDecl->getLocation(), diag::err_vla_decl_in_file_scope) << 2585 SizeRange; 2586 2587 IDecl->setInvalidDecl(); 2588 } else { 2589 // C99 6.7.5.2p2: If an identifier is declared to be an object with 2590 // static storage duration, it shall not have a variable length array. 2591 if (IDecl->getStorageClass() == VarDecl::Static) { 2592 Diag(IDecl->getLocation(), diag::err_vla_decl_has_static_storage) 2593 << SizeRange; 2594 IDecl->setInvalidDecl(); 2595 } else if (IDecl->getStorageClass() == VarDecl::Extern) { 2596 Diag(IDecl->getLocation(), diag::err_vla_decl_has_extern_linkage) 2597 << SizeRange; 2598 IDecl->setInvalidDecl(); 2599 } 2600 } 2601 } else if (T->isVariablyModifiedType()) { 2602 if (IDecl->isFileVarDecl()) { 2603 Diag(IDecl->getLocation(), diag::err_vm_decl_in_file_scope); 2604 IDecl->setInvalidDecl(); 2605 } else { 2606 if (IDecl->getStorageClass() == VarDecl::Extern) { 2607 Diag(IDecl->getLocation(), diag::err_vm_decl_has_extern_linkage); 2608 IDecl->setInvalidDecl(); 2609 } 2610 } 2611 } 2612 2613 // Block scope. C99 6.7p7: If an identifier for an object is declared with 2614 // no linkage (C99 6.2.2p6), the type for the object shall be complete... 2615 if (IDecl->isBlockVarDecl() && 2616 IDecl->getStorageClass() != VarDecl::Extern) { 2617 if (!IDecl->isInvalidDecl() && 2618 DiagnoseIncompleteType(IDecl->getLocation(), T, 2619 diag::err_typecheck_decl_incomplete_type)) 2620 IDecl->setInvalidDecl(); 2621 } 2622 // File scope. C99 6.9.2p2: A declaration of an identifier for and 2623 // object that has file scope without an initializer, and without a 2624 // storage-class specifier or with the storage-class specifier "static", 2625 // constitutes a tentative definition. Note: A tentative definition with 2626 // external linkage is valid (C99 6.2.2p5). 2627 if (isTentativeDefinition(IDecl)) { 2628 if (T->isIncompleteArrayType()) { 2629 // C99 6.9.2 (p2, p5): Implicit initialization causes an incomplete 2630 // array to be completed. Don't issue a diagnostic. 2631 } else if (!IDecl->isInvalidDecl() && 2632 DiagnoseIncompleteType(IDecl->getLocation(), T, 2633 diag::err_typecheck_decl_incomplete_type)) 2634 // C99 6.9.2p3: If the declaration of an identifier for an object is 2635 // a tentative definition and has internal linkage (C99 6.2.2p3), the 2636 // declared type shall not be an incomplete type. 2637 IDecl->setInvalidDecl(); 2638 } 2639 if (IDecl->isFileVarDecl()) 2640 CheckForFileScopedRedefinitions(S, IDecl); 2641 } 2642 return NewGroup; 2643} 2644 2645/// ActOnParamDeclarator - Called from Parser::ParseFunctionDeclarator() 2646/// to introduce parameters into function prototype scope. 2647Sema::DeclTy * 2648Sema::ActOnParamDeclarator(Scope *S, Declarator &D) { 2649 const DeclSpec &DS = D.getDeclSpec(); 2650 2651 // Verify C99 6.7.5.3p2: The only SCS allowed is 'register'. 2652 VarDecl::StorageClass StorageClass = VarDecl::None; 2653 if (DS.getStorageClassSpec() == DeclSpec::SCS_register) { 2654 StorageClass = VarDecl::Register; 2655 } else if (DS.getStorageClassSpec() != DeclSpec::SCS_unspecified) { 2656 Diag(DS.getStorageClassSpecLoc(), 2657 diag::err_invalid_storage_class_in_func_decl); 2658 D.getMutableDeclSpec().ClearStorageClassSpecs(); 2659 } 2660 if (DS.isThreadSpecified()) { 2661 Diag(DS.getThreadSpecLoc(), 2662 diag::err_invalid_storage_class_in_func_decl); 2663 D.getMutableDeclSpec().ClearStorageClassSpecs(); 2664 } 2665 2666 // Check that there are no default arguments inside the type of this 2667 // parameter (C++ only). 2668 if (getLangOptions().CPlusPlus) 2669 CheckExtraCXXDefaultArguments(D); 2670 2671 // In this context, we *do not* check D.getInvalidType(). If the declarator 2672 // type was invalid, GetTypeForDeclarator() still returns a "valid" type, 2673 // though it will not reflect the user specified type. 2674 QualType parmDeclType = GetTypeForDeclarator(D, S); 2675 2676 assert(!parmDeclType.isNull() && "GetTypeForDeclarator() returned null type"); 2677 2678 // TODO: CHECK FOR CONFLICTS, multiple decls with same name in one scope. 2679 // Can this happen for params? We already checked that they don't conflict 2680 // among each other. Here they can only shadow globals, which is ok. 2681 IdentifierInfo *II = D.getIdentifier(); 2682 if (II) { 2683 if (NamedDecl *PrevDecl = LookupName(S, II, LookupOrdinaryName)) { 2684 if (PrevDecl->isTemplateParameter()) { 2685 // Maybe we will complain about the shadowed template parameter. 2686 DiagnoseTemplateParameterShadow(D.getIdentifierLoc(), PrevDecl); 2687 // Just pretend that we didn't see the previous declaration. 2688 PrevDecl = 0; 2689 } else if (S->isDeclScope(PrevDecl)) { 2690 Diag(D.getIdentifierLoc(), diag::err_param_redefinition) << II; 2691 2692 // Recover by removing the name 2693 II = 0; 2694 D.SetIdentifier(0, D.getIdentifierLoc()); 2695 } 2696 } 2697 } 2698 2699 // Perform the default function/array conversion (C99 6.7.5.3p[7,8]). 2700 // Doing the promotion here has a win and a loss. The win is the type for 2701 // both Decl's and DeclRefExpr's will match (a convenient invariant for the 2702 // code generator). The loss is the orginal type isn't preserved. For example: 2703 // 2704 // void func(int parmvardecl[5]) { // convert "int [5]" to "int *" 2705 // int blockvardecl[5]; 2706 // sizeof(parmvardecl); // size == 4 2707 // sizeof(blockvardecl); // size == 20 2708 // } 2709 // 2710 // For expressions, all implicit conversions are captured using the 2711 // ImplicitCastExpr AST node (we have no such mechanism for Decl's). 2712 // 2713 // FIXME: If a source translation tool needs to see the original type, then 2714 // we need to consider storing both types (in ParmVarDecl)... 2715 // 2716 if (parmDeclType->isArrayType()) { 2717 // int x[restrict 4] -> int *restrict 2718 parmDeclType = Context.getArrayDecayedType(parmDeclType); 2719 } else if (parmDeclType->isFunctionType()) 2720 parmDeclType = Context.getPointerType(parmDeclType); 2721 2722 ParmVarDecl *New = ParmVarDecl::Create(Context, CurContext, 2723 D.getIdentifierLoc(), II, 2724 parmDeclType, StorageClass, 2725 0); 2726 2727 if (D.getInvalidType()) 2728 New->setInvalidDecl(); 2729 2730 // Parameter declarators cannot be qualified (C++ [dcl.meaning]p1). 2731 if (D.getCXXScopeSpec().isSet()) { 2732 Diag(D.getIdentifierLoc(), diag::err_qualified_param_declarator) 2733 << D.getCXXScopeSpec().getRange(); 2734 New->setInvalidDecl(); 2735 } 2736 2737 // Add the parameter declaration into this scope. 2738 S->AddDecl(New); 2739 if (II) 2740 IdResolver.AddDecl(New); 2741 2742 ProcessDeclAttributes(New, D); 2743 return New; 2744 2745} 2746 2747void Sema::ActOnFinishKNRParamDeclarations(Scope *S, Declarator &D) { 2748 assert(D.getTypeObject(0).Kind == DeclaratorChunk::Function && 2749 "Not a function declarator!"); 2750 DeclaratorChunk::FunctionTypeInfo &FTI = D.getTypeObject(0).Fun; 2751 2752 // Verify 6.9.1p6: 'every identifier in the identifier list shall be declared' 2753 // for a K&R function. 2754 if (!FTI.hasPrototype) { 2755 for (unsigned i = 0, e = FTI.NumArgs; i != e; ++i) { 2756 if (FTI.ArgInfo[i].Param == 0) { 2757 Diag(FTI.ArgInfo[i].IdentLoc, diag::ext_param_not_declared) 2758 << FTI.ArgInfo[i].Ident; 2759 // Implicitly declare the argument as type 'int' for lack of a better 2760 // type. 2761 DeclSpec DS; 2762 const char* PrevSpec; // unused 2763 DS.SetTypeSpecType(DeclSpec::TST_int, FTI.ArgInfo[i].IdentLoc, 2764 PrevSpec); 2765 Declarator ParamD(DS, Declarator::KNRTypeListContext); 2766 ParamD.SetIdentifier(FTI.ArgInfo[i].Ident, FTI.ArgInfo[i].IdentLoc); 2767 FTI.ArgInfo[i].Param = ActOnParamDeclarator(S, ParamD); 2768 } 2769 } 2770 } 2771} 2772 2773Sema::DeclTy *Sema::ActOnStartOfFunctionDef(Scope *FnBodyScope, Declarator &D) { 2774 assert(getCurFunctionDecl() == 0 && "Function parsing confused"); 2775 assert(D.getTypeObject(0).Kind == DeclaratorChunk::Function && 2776 "Not a function declarator!"); 2777 DeclaratorChunk::FunctionTypeInfo &FTI = D.getTypeObject(0).Fun; 2778 2779 if (FTI.hasPrototype) { 2780 // FIXME: Diagnose arguments without names in C. 2781 } 2782 2783 Scope *ParentScope = FnBodyScope->getParent(); 2784 2785 return ActOnStartOfFunctionDef(FnBodyScope, 2786 ActOnDeclarator(ParentScope, D, 0, 2787 /*IsFunctionDefinition=*/true)); 2788} 2789 2790Sema::DeclTy *Sema::ActOnStartOfFunctionDef(Scope *FnBodyScope, DeclTy *D) { 2791 Decl *decl = static_cast<Decl*>(D); 2792 FunctionDecl *FD = cast<FunctionDecl>(decl); 2793 2794 // See if this is a redefinition. 2795 const FunctionDecl *Definition; 2796 if (FD->getBody(Definition)) { 2797 Diag(FD->getLocation(), diag::err_redefinition) << FD->getDeclName(); 2798 Diag(Definition->getLocation(), diag::note_previous_definition); 2799 } 2800 2801 // Builtin functions cannot be defined. 2802 if (unsigned BuiltinID = FD->getBuiltinID(Context)) { 2803 if (Context.BuiltinInfo.isPredefinedLibFunction(BuiltinID)) { 2804 Diag(FD->getLocation(), diag::err_builtin_lib_definition) << FD; 2805 Diag(FD->getLocation(), diag::note_builtin_lib_def_freestanding); 2806 } else 2807 Diag(FD->getLocation(), diag::err_builtin_definition) << FD; 2808 FD->setInvalidDecl(); 2809 } 2810 2811 PushDeclContext(FnBodyScope, FD); 2812 2813 // Check the validity of our function parameters 2814 CheckParmsForFunctionDef(FD); 2815 2816 // Introduce our parameters into the function scope 2817 for (unsigned p = 0, NumParams = FD->getNumParams(); p < NumParams; ++p) { 2818 ParmVarDecl *Param = FD->getParamDecl(p); 2819 Param->setOwningFunction(FD); 2820 2821 // If this has an identifier, add it to the scope stack. 2822 if (Param->getIdentifier()) 2823 PushOnScopeChains(Param, FnBodyScope); 2824 } 2825 2826 // Checking attributes of current function definition 2827 // dllimport attribute. 2828 if (FD->getAttr<DLLImportAttr>() && (!FD->getAttr<DLLExportAttr>())) { 2829 // dllimport attribute cannot be applied to definition. 2830 if (!(FD->getAttr<DLLImportAttr>())->isInherited()) { 2831 Diag(FD->getLocation(), 2832 diag::err_attribute_can_be_applied_only_to_symbol_declaration) 2833 << "dllimport"; 2834 FD->setInvalidDecl(); 2835 return FD; 2836 } else { 2837 // If a symbol previously declared dllimport is later defined, the 2838 // attribute is ignored in subsequent references, and a warning is 2839 // emitted. 2840 Diag(FD->getLocation(), 2841 diag::warn_redeclaration_without_attribute_prev_attribute_ignored) 2842 << FD->getNameAsCString() << "dllimport"; 2843 } 2844 } 2845 return FD; 2846} 2847 2848Sema::DeclTy *Sema::ActOnFinishFunctionBody(DeclTy *D, StmtArg BodyArg) { 2849 Decl *dcl = static_cast<Decl *>(D); 2850 Stmt *Body = static_cast<Stmt*>(BodyArg.release()); 2851 if (FunctionDecl *FD = dyn_cast_or_null<FunctionDecl>(dcl)) { 2852 FD->setBody(Body); 2853 assert(FD == getCurFunctionDecl() && "Function parsing confused"); 2854 } else if (ObjCMethodDecl *MD = dyn_cast_or_null<ObjCMethodDecl>(dcl)) { 2855 assert(MD == getCurMethodDecl() && "Method parsing confused"); 2856 MD->setBody((Stmt*)Body); 2857 } else { 2858 Body->Destroy(Context); 2859 return 0; 2860 } 2861 PopDeclContext(); 2862 // Verify and clean out per-function state. 2863 2864 // Check goto/label use. 2865 for (llvm::DenseMap<IdentifierInfo*, LabelStmt*>::iterator 2866 I = LabelMap.begin(), E = LabelMap.end(); I != E; ++I) { 2867 // Verify that we have no forward references left. If so, there was a goto 2868 // or address of a label taken, but no definition of it. Label fwd 2869 // definitions are indicated with a null substmt. 2870 if (I->second->getSubStmt() == 0) { 2871 LabelStmt *L = I->second; 2872 // Emit error. 2873 Diag(L->getIdentLoc(), diag::err_undeclared_label_use) << L->getName(); 2874 2875 // At this point, we have gotos that use the bogus label. Stitch it into 2876 // the function body so that they aren't leaked and that the AST is well 2877 // formed. 2878 if (Body) { 2879#if 0 2880 // FIXME: Why do this? Having a 'push_back' in CompoundStmt is ugly, 2881 // and the AST is malformed anyway. We should just blow away 'L'. 2882 L->setSubStmt(new (Context) NullStmt(L->getIdentLoc())); 2883 cast<CompoundStmt>(Body)->push_back(L); 2884#else 2885 L->Destroy(Context); 2886#endif 2887 } else { 2888 // The whole function wasn't parsed correctly, just delete this. 2889 L->Destroy(Context); 2890 } 2891 } 2892 } 2893 LabelMap.clear(); 2894 2895 return D; 2896} 2897 2898/// ImplicitlyDefineFunction - An undeclared identifier was used in a function 2899/// call, forming a call to an implicitly defined function (per C99 6.5.1p2). 2900NamedDecl *Sema::ImplicitlyDefineFunction(SourceLocation Loc, 2901 IdentifierInfo &II, Scope *S) { 2902 // Extension in C99. Legal in C90, but warn about it. 2903 if (getLangOptions().C99) 2904 Diag(Loc, diag::ext_implicit_function_decl) << &II; 2905 else 2906 Diag(Loc, diag::warn_implicit_function_decl) << &II; 2907 2908 // FIXME: handle stuff like: 2909 // void foo() { extern float X(); } 2910 // void bar() { X(); } <-- implicit decl for X in another scope. 2911 2912 // Set a Declarator for the implicit definition: int foo(); 2913 const char *Dummy; 2914 DeclSpec DS; 2915 bool Error = DS.SetTypeSpecType(DeclSpec::TST_int, Loc, Dummy); 2916 Error = Error; // Silence warning. 2917 assert(!Error && "Error setting up implicit decl!"); 2918 Declarator D(DS, Declarator::BlockContext); 2919 D.AddTypeInfo(DeclaratorChunk::getFunction(false, false, 0, 0, 0, Loc, D), 2920 SourceLocation()); 2921 D.SetIdentifier(&II, Loc); 2922 2923 // Insert this function into translation-unit scope. 2924 2925 DeclContext *PrevDC = CurContext; 2926 CurContext = Context.getTranslationUnitDecl(); 2927 2928 FunctionDecl *FD = 2929 dyn_cast<FunctionDecl>(static_cast<Decl*>(ActOnDeclarator(TUScope, D, 0))); 2930 FD->setImplicit(); 2931 2932 CurContext = PrevDC; 2933 2934 AddKnownFunctionAttributes(FD); 2935 2936 return FD; 2937} 2938 2939/// \brief Adds any function attributes that we know a priori based on 2940/// the declaration of this function. 2941/// 2942/// These attributes can apply both to implicitly-declared builtins 2943/// (like __builtin___printf_chk) or to library-declared functions 2944/// like NSLog or printf. 2945void Sema::AddKnownFunctionAttributes(FunctionDecl *FD) { 2946 if (FD->isInvalidDecl()) 2947 return; 2948 2949 // If this is a built-in function, map its builtin attributes to 2950 // actual attributes. 2951 if (unsigned BuiltinID = FD->getBuiltinID(Context)) { 2952 // Handle printf-formatting attributes. 2953 unsigned FormatIdx; 2954 bool HasVAListArg; 2955 if (Context.BuiltinInfo.isPrintfLike(BuiltinID, FormatIdx, HasVAListArg)) { 2956 if (!FD->getAttr<FormatAttr>()) 2957 FD->addAttr(new FormatAttr("printf", FormatIdx + 1, FormatIdx + 2)); 2958 } 2959 } 2960 2961 IdentifierInfo *Name = FD->getIdentifier(); 2962 if (!Name) 2963 return; 2964 if ((!getLangOptions().CPlusPlus && 2965 FD->getDeclContext()->isTranslationUnit()) || 2966 (isa<LinkageSpecDecl>(FD->getDeclContext()) && 2967 cast<LinkageSpecDecl>(FD->getDeclContext())->getLanguage() == 2968 LinkageSpecDecl::lang_c)) { 2969 // Okay: this could be a libc/libm/Objective-C function we know 2970 // about. 2971 } else 2972 return; 2973 2974 unsigned KnownID; 2975 for (KnownID = 0; KnownID != id_num_known_functions; ++KnownID) 2976 if (KnownFunctionIDs[KnownID] == Name) 2977 break; 2978 2979 switch (KnownID) { 2980 case id_NSLog: 2981 case id_NSLogv: 2982 if (const FormatAttr *Format = FD->getAttr<FormatAttr>()) { 2983 // FIXME: We known better than our headers. 2984 const_cast<FormatAttr *>(Format)->setType("printf"); 2985 } else 2986 FD->addAttr(new FormatAttr("printf", 1, 2)); 2987 break; 2988 2989 case id_asprintf: 2990 case id_vasprintf: 2991 if (!FD->getAttr<FormatAttr>()) 2992 FD->addAttr(new FormatAttr("printf", 2, 3)); 2993 break; 2994 2995 default: 2996 // Unknown function or known function without any attributes to 2997 // add. Do nothing. 2998 break; 2999 } 3000} 3001 3002TypedefDecl *Sema::ParseTypedefDecl(Scope *S, Declarator &D, QualType T, 3003 Decl *LastDeclarator) { 3004 assert(D.getIdentifier() && "Wrong callback for declspec without declarator"); 3005 assert(!T.isNull() && "GetTypeForDeclarator() returned null type"); 3006 3007 // Scope manipulation handled by caller. 3008 TypedefDecl *NewTD = TypedefDecl::Create(Context, CurContext, 3009 D.getIdentifierLoc(), 3010 D.getIdentifier(), 3011 T); 3012 NewTD->setNextDeclarator(LastDeclarator); 3013 if (D.getInvalidType()) 3014 NewTD->setInvalidDecl(); 3015 return NewTD; 3016} 3017 3018/// ActOnTag - This is invoked when we see 'struct foo' or 'struct {'. In the 3019/// former case, Name will be non-null. In the later case, Name will be null. 3020/// TagSpec indicates what kind of tag this is. TK indicates whether this is a 3021/// reference/declaration/definition of a tag. 3022Sema::DeclTy *Sema::ActOnTag(Scope *S, unsigned TagSpec, TagKind TK, 3023 SourceLocation KWLoc, const CXXScopeSpec &SS, 3024 IdentifierInfo *Name, SourceLocation NameLoc, 3025 AttributeList *Attr) { 3026 // If this is not a definition, it must have a name. 3027 assert((Name != 0 || TK == TK_Definition) && 3028 "Nameless record must be a definition!"); 3029 3030 TagDecl::TagKind Kind; 3031 switch (TagSpec) { 3032 default: assert(0 && "Unknown tag type!"); 3033 case DeclSpec::TST_struct: Kind = TagDecl::TK_struct; break; 3034 case DeclSpec::TST_union: Kind = TagDecl::TK_union; break; 3035 case DeclSpec::TST_class: Kind = TagDecl::TK_class; break; 3036 case DeclSpec::TST_enum: Kind = TagDecl::TK_enum; break; 3037 } 3038 3039 DeclContext *SearchDC = CurContext; 3040 DeclContext *DC = CurContext; 3041 NamedDecl *PrevDecl = 0; 3042 3043 bool Invalid = false; 3044 3045 if (Name && SS.isNotEmpty()) { 3046 // We have a nested-name tag ('struct foo::bar'). 3047 3048 // Check for invalid 'foo::'. 3049 if (SS.isInvalid()) { 3050 Name = 0; 3051 goto CreateNewDecl; 3052 } 3053 3054 DC = static_cast<DeclContext*>(SS.getScopeRep()); 3055 SearchDC = DC; 3056 // Look-up name inside 'foo::'. 3057 PrevDecl = dyn_cast_or_null<TagDecl>( 3058 LookupQualifiedName(DC, Name, LookupTagName, true).getAsDecl()); 3059 3060 // A tag 'foo::bar' must already exist. 3061 if (PrevDecl == 0) { 3062 Diag(NameLoc, diag::err_not_tag_in_scope) << Name << SS.getRange(); 3063 Name = 0; 3064 goto CreateNewDecl; 3065 } 3066 } else if (Name) { 3067 // If this is a named struct, check to see if there was a previous forward 3068 // declaration or definition. 3069 // FIXME: We're looking into outer scopes here, even when we 3070 // shouldn't be. Doing so can result in ambiguities that we 3071 // shouldn't be diagnosing. 3072 LookupResult R = LookupName(S, Name, LookupTagName, 3073 /*RedeclarationOnly=*/(TK != TK_Reference)); 3074 if (R.isAmbiguous()) { 3075 DiagnoseAmbiguousLookup(R, Name, NameLoc); 3076 // FIXME: This is not best way to recover from case like: 3077 // 3078 // struct S s; 3079 // 3080 // causes needless err_ovl_no_viable_function_in_init latter. 3081 Name = 0; 3082 PrevDecl = 0; 3083 Invalid = true; 3084 } 3085 else 3086 PrevDecl = R; 3087 3088 if (!getLangOptions().CPlusPlus && TK != TK_Reference) { 3089 // FIXME: This makes sure that we ignore the contexts associated 3090 // with C structs, unions, and enums when looking for a matching 3091 // tag declaration or definition. See the similar lookup tweak 3092 // in Sema::LookupName; is there a better way to deal with this? 3093 while (isa<RecordDecl>(SearchDC) || isa<EnumDecl>(SearchDC)) 3094 SearchDC = SearchDC->getParent(); 3095 } 3096 } 3097 3098 if (PrevDecl && PrevDecl->isTemplateParameter()) { 3099 // Maybe we will complain about the shadowed template parameter. 3100 DiagnoseTemplateParameterShadow(NameLoc, PrevDecl); 3101 // Just pretend that we didn't see the previous declaration. 3102 PrevDecl = 0; 3103 } 3104 3105 if (PrevDecl) { 3106 // If the previous declaration was deprecated, emit a warning. 3107 DiagnoseUseOfDeprecatedDecl(PrevDecl, NameLoc); 3108 3109 if (TagDecl *PrevTagDecl = dyn_cast<TagDecl>(PrevDecl)) { 3110 // If this is a use of a previous tag, or if the tag is already declared 3111 // in the same scope (so that the definition/declaration completes or 3112 // rementions the tag), reuse the decl. 3113 if (TK == TK_Reference || isDeclInScope(PrevDecl, SearchDC, S)) { 3114 // Make sure that this wasn't declared as an enum and now used as a 3115 // struct or something similar. 3116 if (PrevTagDecl->getTagKind() != Kind) { 3117 Diag(KWLoc, diag::err_use_with_wrong_tag) << Name; 3118 Diag(PrevDecl->getLocation(), diag::note_previous_use); 3119 // Recover by making this an anonymous redefinition. 3120 Name = 0; 3121 PrevDecl = 0; 3122 Invalid = true; 3123 } else { 3124 // If this is a use, just return the declaration we found. 3125 3126 // FIXME: In the future, return a variant or some other clue 3127 // for the consumer of this Decl to know it doesn't own it. 3128 // For our current ASTs this shouldn't be a problem, but will 3129 // need to be changed with DeclGroups. 3130 if (TK == TK_Reference) 3131 return PrevDecl; 3132 3133 // Diagnose attempts to redefine a tag. 3134 if (TK == TK_Definition) { 3135 if (TagDecl *Def = PrevTagDecl->getDefinition(Context)) { 3136 Diag(NameLoc, diag::err_redefinition) << Name; 3137 Diag(Def->getLocation(), diag::note_previous_definition); 3138 // If this is a redefinition, recover by making this 3139 // struct be anonymous, which will make any later 3140 // references get the previous definition. 3141 Name = 0; 3142 PrevDecl = 0; 3143 Invalid = true; 3144 } else { 3145 // If the type is currently being defined, complain 3146 // about a nested redefinition. 3147 TagType *Tag = cast<TagType>(Context.getTagDeclType(PrevTagDecl)); 3148 if (Tag->isBeingDefined()) { 3149 Diag(NameLoc, diag::err_nested_redefinition) << Name; 3150 Diag(PrevTagDecl->getLocation(), 3151 diag::note_previous_definition); 3152 Name = 0; 3153 PrevDecl = 0; 3154 Invalid = true; 3155 } 3156 } 3157 3158 // Okay, this is definition of a previously declared or referenced 3159 // tag PrevDecl. We're going to create a new Decl for it. 3160 } 3161 } 3162 // If we get here we have (another) forward declaration or we 3163 // have a definition. Just create a new decl. 3164 } else { 3165 // If we get here, this is a definition of a new tag type in a nested 3166 // scope, e.g. "struct foo; void bar() { struct foo; }", just create a 3167 // new decl/type. We set PrevDecl to NULL so that the entities 3168 // have distinct types. 3169 PrevDecl = 0; 3170 } 3171 // If we get here, we're going to create a new Decl. If PrevDecl 3172 // is non-NULL, it's a definition of the tag declared by 3173 // PrevDecl. If it's NULL, we have a new definition. 3174 } else { 3175 // PrevDecl is a namespace, template, or anything else 3176 // that lives in the IDNS_Tag identifier namespace. 3177 if (isDeclInScope(PrevDecl, SearchDC, S)) { 3178 // The tag name clashes with a namespace name, issue an error and 3179 // recover by making this tag be anonymous. 3180 Diag(NameLoc, diag::err_redefinition_different_kind) << Name; 3181 Diag(PrevDecl->getLocation(), diag::note_previous_definition); 3182 Name = 0; 3183 PrevDecl = 0; 3184 Invalid = true; 3185 } else { 3186 // The existing declaration isn't relevant to us; we're in a 3187 // new scope, so clear out the previous declaration. 3188 PrevDecl = 0; 3189 } 3190 } 3191 } else if (TK == TK_Reference && SS.isEmpty() && Name && 3192 (Kind != TagDecl::TK_enum)) { 3193 // C++ [basic.scope.pdecl]p5: 3194 // -- for an elaborated-type-specifier of the form 3195 // 3196 // class-key identifier 3197 // 3198 // if the elaborated-type-specifier is used in the 3199 // decl-specifier-seq or parameter-declaration-clause of a 3200 // function defined in namespace scope, the identifier is 3201 // declared as a class-name in the namespace that contains 3202 // the declaration; otherwise, except as a friend 3203 // declaration, the identifier is declared in the smallest 3204 // non-class, non-function-prototype scope that contains the 3205 // declaration. 3206 // 3207 // C99 6.7.2.3p8 has a similar (but not identical!) provision for 3208 // C structs and unions. 3209 3210 // Find the context where we'll be declaring the tag. 3211 // FIXME: We would like to maintain the current DeclContext as the 3212 // lexical context, 3213 while (SearchDC->isRecord()) 3214 SearchDC = SearchDC->getParent(); 3215 3216 // Find the scope where we'll be declaring the tag. 3217 while (S->isClassScope() || 3218 (getLangOptions().CPlusPlus && S->isFunctionPrototypeScope()) || 3219 ((S->getFlags() & Scope::DeclScope) == 0) || 3220 (S->getEntity() && 3221 ((DeclContext *)S->getEntity())->isTransparentContext())) 3222 S = S->getParent(); 3223 } 3224 3225CreateNewDecl: 3226 3227 // If there is an identifier, use the location of the identifier as the 3228 // location of the decl, otherwise use the location of the struct/union 3229 // keyword. 3230 SourceLocation Loc = NameLoc.isValid() ? NameLoc : KWLoc; 3231 3232 // Otherwise, create a new declaration. If there is a previous 3233 // declaration of the same entity, the two will be linked via 3234 // PrevDecl. 3235 TagDecl *New; 3236 3237 if (Kind == TagDecl::TK_enum) { 3238 // FIXME: Tag decls should be chained to any simultaneous vardecls, e.g.: 3239 // enum X { A, B, C } D; D should chain to X. 3240 New = EnumDecl::Create(Context, SearchDC, Loc, Name, 3241 cast_or_null<EnumDecl>(PrevDecl)); 3242 // If this is an undefined enum, warn. 3243 if (TK != TK_Definition) Diag(Loc, diag::ext_forward_ref_enum); 3244 } else { 3245 // struct/union/class 3246 3247 // FIXME: Tag decls should be chained to any simultaneous vardecls, e.g.: 3248 // struct X { int A; } D; D should chain to X. 3249 if (getLangOptions().CPlusPlus) 3250 // FIXME: Look for a way to use RecordDecl for simple structs. 3251 New = CXXRecordDecl::Create(Context, Kind, SearchDC, Loc, Name, 3252 cast_or_null<CXXRecordDecl>(PrevDecl)); 3253 else 3254 New = RecordDecl::Create(Context, Kind, SearchDC, Loc, Name, 3255 cast_or_null<RecordDecl>(PrevDecl)); 3256 } 3257 3258 if (Kind != TagDecl::TK_enum) { 3259 // Handle #pragma pack: if the #pragma pack stack has non-default 3260 // alignment, make up a packed attribute for this decl. These 3261 // attributes are checked when the ASTContext lays out the 3262 // structure. 3263 // 3264 // It is important for implementing the correct semantics that this 3265 // happen here (in act on tag decl). The #pragma pack stack is 3266 // maintained as a result of parser callbacks which can occur at 3267 // many points during the parsing of a struct declaration (because 3268 // the #pragma tokens are effectively skipped over during the 3269 // parsing of the struct). 3270 if (unsigned Alignment = PackContext.getAlignment()) 3271 New->addAttr(new PackedAttr(Alignment * 8)); 3272 } 3273 3274 if (getLangOptions().CPlusPlus && SS.isEmpty() && Name && !Invalid) { 3275 // C++ [dcl.typedef]p3: 3276 // [...] Similarly, in a given scope, a class or enumeration 3277 // shall not be declared with the same name as a typedef-name 3278 // that is declared in that scope and refers to a type other 3279 // than the class or enumeration itself. 3280 LookupResult Lookup = LookupName(S, Name, LookupOrdinaryName, true); 3281 TypedefDecl *PrevTypedef = 0; 3282 if (Lookup.getKind() == LookupResult::Found) 3283 PrevTypedef = dyn_cast<TypedefDecl>(Lookup.getAsDecl()); 3284 3285 if (PrevTypedef && isDeclInScope(PrevTypedef, SearchDC, S) && 3286 Context.getCanonicalType(Context.getTypeDeclType(PrevTypedef)) != 3287 Context.getCanonicalType(Context.getTypeDeclType(New))) { 3288 Diag(Loc, diag::err_tag_definition_of_typedef) 3289 << Context.getTypeDeclType(New) 3290 << PrevTypedef->getUnderlyingType(); 3291 Diag(PrevTypedef->getLocation(), diag::note_previous_definition); 3292 Invalid = true; 3293 } 3294 } 3295 3296 if (Invalid) 3297 New->setInvalidDecl(); 3298 3299 if (Attr) 3300 ProcessDeclAttributeList(New, Attr); 3301 3302 // If we're declaring or defining a tag in function prototype scope 3303 // in C, note that this type can only be used within the function. 3304 if (Name && S->isFunctionPrototypeScope() && !getLangOptions().CPlusPlus) 3305 Diag(Loc, diag::warn_decl_in_param_list) << Context.getTagDeclType(New); 3306 3307 // Set the lexical context. If the tag has a C++ scope specifier, the 3308 // lexical context will be different from the semantic context. 3309 New->setLexicalDeclContext(CurContext); 3310 3311 if (TK == TK_Definition) 3312 New->startDefinition(); 3313 3314 // If this has an identifier, add it to the scope stack. 3315 if (Name) { 3316 S = getNonFieldDeclScope(S); 3317 PushOnScopeChains(New, S); 3318 } else { 3319 CurContext->addDecl(New); 3320 } 3321 3322 return New; 3323} 3324 3325void Sema::ActOnTagStartDefinition(Scope *S, DeclTy *TagD) { 3326 AdjustDeclIfTemplate(TagD); 3327 TagDecl *Tag = cast<TagDecl>((Decl *)TagD); 3328 3329 // Enter the tag context. 3330 PushDeclContext(S, Tag); 3331 3332 if (CXXRecordDecl *Record = dyn_cast<CXXRecordDecl>(Tag)) { 3333 FieldCollector->StartClass(); 3334 3335 if (Record->getIdentifier()) { 3336 // C++ [class]p2: 3337 // [...] The class-name is also inserted into the scope of the 3338 // class itself; this is known as the injected-class-name. For 3339 // purposes of access checking, the injected-class-name is treated 3340 // as if it were a public member name. 3341 RecordDecl *InjectedClassName 3342 = CXXRecordDecl::Create(Context, Record->getTagKind(), 3343 CurContext, Record->getLocation(), 3344 Record->getIdentifier(), Record); 3345 InjectedClassName->setImplicit(); 3346 PushOnScopeChains(InjectedClassName, S); 3347 } 3348 } 3349} 3350 3351void Sema::ActOnTagFinishDefinition(Scope *S, DeclTy *TagD) { 3352 AdjustDeclIfTemplate(TagD); 3353 TagDecl *Tag = cast<TagDecl>((Decl *)TagD); 3354 3355 if (isa<CXXRecordDecl>(Tag)) 3356 FieldCollector->FinishClass(); 3357 3358 // Exit this scope of this tag's definition. 3359 PopDeclContext(); 3360 3361 // Notify the consumer that we've defined a tag. 3362 Consumer.HandleTagDeclDefinition(Tag); 3363} 3364 3365/// TryToFixInvalidVariablyModifiedType - Helper method to turn variable array 3366/// types into constant array types in certain situations which would otherwise 3367/// be errors (for GCC compatibility). 3368static QualType TryToFixInvalidVariablyModifiedType(QualType T, 3369 ASTContext &Context) { 3370 // This method tries to turn a variable array into a constant 3371 // array even when the size isn't an ICE. This is necessary 3372 // for compatibility with code that depends on gcc's buggy 3373 // constant expression folding, like struct {char x[(int)(char*)2];} 3374 const VariableArrayType* VLATy = dyn_cast<VariableArrayType>(T); 3375 if (!VLATy) return QualType(); 3376 3377 Expr::EvalResult EvalResult; 3378 if (!VLATy->getSizeExpr() || 3379 !VLATy->getSizeExpr()->Evaluate(EvalResult, Context)) 3380 return QualType(); 3381 3382 assert(EvalResult.Val.isInt() && "Size expressions must be integers!"); 3383 llvm::APSInt &Res = EvalResult.Val.getInt(); 3384 if (Res >= llvm::APSInt(Res.getBitWidth(), Res.isUnsigned())) 3385 return Context.getConstantArrayType(VLATy->getElementType(), 3386 Res, ArrayType::Normal, 0); 3387 return QualType(); 3388} 3389 3390bool Sema::VerifyBitField(SourceLocation FieldLoc, IdentifierInfo *FieldName, 3391 QualType FieldTy, const Expr *BitWidth) { 3392 // FIXME: 6.7.2.1p4 - verify the field type. 3393 3394 llvm::APSInt Value; 3395 if (VerifyIntegerConstantExpression(BitWidth, &Value)) 3396 return true; 3397 3398 // Zero-width bitfield is ok for anonymous field. 3399 if (Value == 0 && FieldName) 3400 return Diag(FieldLoc, diag::err_bitfield_has_zero_width) << FieldName; 3401 3402 if (Value.isNegative()) 3403 return Diag(FieldLoc, diag::err_bitfield_has_negative_width) << FieldName; 3404 3405 uint64_t TypeSize = Context.getTypeSize(FieldTy); 3406 // FIXME: We won't need the 0 size once we check that the field type is valid. 3407 if (TypeSize && Value.getZExtValue() > TypeSize) 3408 return Diag(FieldLoc, diag::err_bitfield_width_exceeds_type_size) 3409 << FieldName << (unsigned)TypeSize; 3410 3411 return false; 3412} 3413 3414/// ActOnField - Each field of a struct/union/class is passed into this in order 3415/// to create a FieldDecl object for it. 3416Sema::DeclTy *Sema::ActOnField(Scope *S, DeclTy *TagD, 3417 SourceLocation DeclStart, 3418 Declarator &D, ExprTy *BitfieldWidth) { 3419 IdentifierInfo *II = D.getIdentifier(); 3420 Expr *BitWidth = (Expr*)BitfieldWidth; 3421 SourceLocation Loc = DeclStart; 3422 RecordDecl *Record = (RecordDecl *)TagD; 3423 if (II) Loc = D.getIdentifierLoc(); 3424 3425 // FIXME: Unnamed fields can be handled in various different ways, for 3426 // example, unnamed unions inject all members into the struct namespace! 3427 3428 QualType T = GetTypeForDeclarator(D, S); 3429 assert(!T.isNull() && "GetTypeForDeclarator() returned null type"); 3430 bool InvalidDecl = false; 3431 3432 // C99 6.7.2.1p8: A member of a structure or union may have any type other 3433 // than a variably modified type. 3434 if (T->isVariablyModifiedType()) { 3435 QualType FixedTy = TryToFixInvalidVariablyModifiedType(T, Context); 3436 if (!FixedTy.isNull()) { 3437 Diag(Loc, diag::warn_illegal_constant_array_size); 3438 T = FixedTy; 3439 } else { 3440 Diag(Loc, diag::err_typecheck_field_variable_size); 3441 T = Context.IntTy; 3442 InvalidDecl = true; 3443 } 3444 } 3445 3446 if (BitWidth) { 3447 if (VerifyBitField(Loc, II, T, BitWidth)) 3448 InvalidDecl = true; 3449 } else { 3450 // Not a bitfield. 3451 3452 // validate II. 3453 3454 } 3455 3456 // FIXME: Chain fielddecls together. 3457 FieldDecl *NewFD; 3458 3459 NewFD = FieldDecl::Create(Context, Record, 3460 Loc, II, T, BitWidth, 3461 D.getDeclSpec().getStorageClassSpec() == 3462 DeclSpec::SCS_mutable); 3463 3464 if (II) { 3465 NamedDecl *PrevDecl = LookupName(S, II, LookupMemberName, true); 3466 if (PrevDecl && isDeclInScope(PrevDecl, CurContext, S) 3467 && !isa<TagDecl>(PrevDecl)) { 3468 Diag(Loc, diag::err_duplicate_member) << II; 3469 Diag(PrevDecl->getLocation(), diag::note_previous_declaration); 3470 NewFD->setInvalidDecl(); 3471 Record->setInvalidDecl(); 3472 } 3473 } 3474 3475 if (getLangOptions().CPlusPlus) { 3476 CheckExtraCXXDefaultArguments(D); 3477 if (!T->isPODType()) 3478 cast<CXXRecordDecl>(Record)->setPOD(false); 3479 } 3480 3481 ProcessDeclAttributes(NewFD, D); 3482 3483 if (D.getInvalidType() || InvalidDecl) 3484 NewFD->setInvalidDecl(); 3485 3486 if (II) { 3487 PushOnScopeChains(NewFD, S); 3488 } else 3489 Record->addDecl(NewFD); 3490 3491 return NewFD; 3492} 3493 3494/// TranslateIvarVisibility - Translate visibility from a token ID to an 3495/// AST enum value. 3496static ObjCIvarDecl::AccessControl 3497TranslateIvarVisibility(tok::ObjCKeywordKind ivarVisibility) { 3498 switch (ivarVisibility) { 3499 default: assert(0 && "Unknown visitibility kind"); 3500 case tok::objc_private: return ObjCIvarDecl::Private; 3501 case tok::objc_public: return ObjCIvarDecl::Public; 3502 case tok::objc_protected: return ObjCIvarDecl::Protected; 3503 case tok::objc_package: return ObjCIvarDecl::Package; 3504 } 3505} 3506 3507/// ActOnIvar - Each ivar field of an objective-c class is passed into this 3508/// in order to create an IvarDecl object for it. 3509Sema::DeclTy *Sema::ActOnIvar(Scope *S, 3510 SourceLocation DeclStart, 3511 Declarator &D, ExprTy *BitfieldWidth, 3512 tok::ObjCKeywordKind Visibility) { 3513 3514 IdentifierInfo *II = D.getIdentifier(); 3515 Expr *BitWidth = (Expr*)BitfieldWidth; 3516 SourceLocation Loc = DeclStart; 3517 if (II) Loc = D.getIdentifierLoc(); 3518 3519 // FIXME: Unnamed fields can be handled in various different ways, for 3520 // example, unnamed unions inject all members into the struct namespace! 3521 3522 QualType T = GetTypeForDeclarator(D, S); 3523 assert(!T.isNull() && "GetTypeForDeclarator() returned null type"); 3524 bool InvalidDecl = false; 3525 3526 if (BitWidth) { 3527 // TODO: Validate. 3528 //printf("WARNING: BITFIELDS IGNORED!\n"); 3529 3530 // 6.7.2.1p3 3531 // 6.7.2.1p4 3532 3533 } else { 3534 // Not a bitfield. 3535 3536 // validate II. 3537 3538 } 3539 3540 // C99 6.7.2.1p8: A member of a structure or union may have any type other 3541 // than a variably modified type. 3542 if (T->isVariablyModifiedType()) { 3543 Diag(Loc, diag::err_typecheck_ivar_variable_size); 3544 InvalidDecl = true; 3545 } 3546 3547 // Get the visibility (access control) for this ivar. 3548 ObjCIvarDecl::AccessControl ac = 3549 Visibility != tok::objc_not_keyword ? TranslateIvarVisibility(Visibility) 3550 : ObjCIvarDecl::None; 3551 3552 // Construct the decl. 3553 ObjCIvarDecl *NewID = ObjCIvarDecl::Create(Context, Loc, II, T, ac, 3554 (Expr *)BitfieldWidth); 3555 3556 if (II) { 3557 NamedDecl *PrevDecl = LookupName(S, II, LookupMemberName, true); 3558 if (PrevDecl && isDeclInScope(PrevDecl, CurContext, S) 3559 && !isa<TagDecl>(PrevDecl)) { 3560 Diag(Loc, diag::err_duplicate_member) << II; 3561 Diag(PrevDecl->getLocation(), diag::note_previous_declaration); 3562 NewID->setInvalidDecl(); 3563 } 3564 } 3565 3566 // Process attributes attached to the ivar. 3567 ProcessDeclAttributes(NewID, D); 3568 3569 if (D.getInvalidType() || InvalidDecl) 3570 NewID->setInvalidDecl(); 3571 3572 if (II) { 3573 // FIXME: When interfaces are DeclContexts, we'll need to add 3574 // these to the interface. 3575 S->AddDecl(NewID); 3576 IdResolver.AddDecl(NewID); 3577 } 3578 3579 return NewID; 3580} 3581 3582void Sema::ActOnFields(Scope* S, 3583 SourceLocation RecLoc, DeclTy *RecDecl, 3584 DeclTy **Fields, unsigned NumFields, 3585 SourceLocation LBrac, SourceLocation RBrac, 3586 AttributeList *Attr) { 3587 Decl *EnclosingDecl = static_cast<Decl*>(RecDecl); 3588 assert(EnclosingDecl && "missing record or interface decl"); 3589 RecordDecl *Record = dyn_cast<RecordDecl>(EnclosingDecl); 3590 3591 // Verify that all the fields are okay. 3592 unsigned NumNamedMembers = 0; 3593 llvm::SmallVector<FieldDecl*, 32> RecFields; 3594 3595 for (unsigned i = 0; i != NumFields; ++i) { 3596 FieldDecl *FD = cast_or_null<FieldDecl>(static_cast<Decl*>(Fields[i])); 3597 assert(FD && "missing field decl"); 3598 3599 // Get the type for the field. 3600 Type *FDTy = FD->getType().getTypePtr(); 3601 3602 if (!FD->isAnonymousStructOrUnion()) { 3603 // Remember all fields written by the user. 3604 RecFields.push_back(FD); 3605 } 3606 3607 // C99 6.7.2.1p2 - A field may not be a function type. 3608 if (FDTy->isFunctionType()) { 3609 Diag(FD->getLocation(), diag::err_field_declared_as_function) 3610 << FD->getDeclName(); 3611 FD->setInvalidDecl(); 3612 EnclosingDecl->setInvalidDecl(); 3613 continue; 3614 } 3615 // C99 6.7.2.1p2 - A field may not be an incomplete type except... 3616 if (FDTy->isIncompleteType()) { 3617 if (!Record) { // Incomplete ivar type is always an error. 3618 DiagnoseIncompleteType(FD->getLocation(), FD->getType(), 3619 diag::err_field_incomplete); 3620 FD->setInvalidDecl(); 3621 EnclosingDecl->setInvalidDecl(); 3622 continue; 3623 } 3624 if (i != NumFields-1 || // ... that the last member ... 3625 !Record->isStruct() || // ... of a structure ... 3626 !FDTy->isArrayType()) { //... may have incomplete array type. 3627 DiagnoseIncompleteType(FD->getLocation(), FD->getType(), 3628 diag::err_field_incomplete); 3629 FD->setInvalidDecl(); 3630 EnclosingDecl->setInvalidDecl(); 3631 continue; 3632 } 3633 if (NumNamedMembers < 1) { //... must have more than named member ... 3634 Diag(FD->getLocation(), diag::err_flexible_array_empty_struct) 3635 << FD->getDeclName(); 3636 FD->setInvalidDecl(); 3637 EnclosingDecl->setInvalidDecl(); 3638 continue; 3639 } 3640 // Okay, we have a legal flexible array member at the end of the struct. 3641 if (Record) 3642 Record->setHasFlexibleArrayMember(true); 3643 } 3644 /// C99 6.7.2.1p2 - a struct ending in a flexible array member cannot be the 3645 /// field of another structure or the element of an array. 3646 if (const RecordType *FDTTy = FDTy->getAsRecordType()) { 3647 if (FDTTy->getDecl()->hasFlexibleArrayMember()) { 3648 // If this is a member of a union, then entire union becomes "flexible". 3649 if (Record && Record->isUnion()) { 3650 Record->setHasFlexibleArrayMember(true); 3651 } else { 3652 // If this is a struct/class and this is not the last element, reject 3653 // it. Note that GCC supports variable sized arrays in the middle of 3654 // structures. 3655 if (i != NumFields-1) { 3656 Diag(FD->getLocation(), diag::err_variable_sized_type_in_struct) 3657 << FD->getDeclName(); 3658 FD->setInvalidDecl(); 3659 EnclosingDecl->setInvalidDecl(); 3660 continue; 3661 } 3662 // We support flexible arrays at the end of structs in other structs 3663 // as an extension. 3664 Diag(FD->getLocation(), diag::ext_flexible_array_in_struct) 3665 << FD->getDeclName(); 3666 if (Record) 3667 Record->setHasFlexibleArrayMember(true); 3668 } 3669 } 3670 } 3671 /// A field cannot be an Objective-c object 3672 if (FDTy->isObjCInterfaceType()) { 3673 Diag(FD->getLocation(), diag::err_statically_allocated_object) 3674 << FD->getDeclName(); 3675 FD->setInvalidDecl(); 3676 EnclosingDecl->setInvalidDecl(); 3677 continue; 3678 } 3679 // Keep track of the number of named members. 3680 if (FD->getIdentifier()) 3681 ++NumNamedMembers; 3682 } 3683 3684 // Okay, we successfully defined 'Record'. 3685 if (Record) { 3686 Record->completeDefinition(Context); 3687 } else { 3688 ObjCIvarDecl **ClsFields = reinterpret_cast<ObjCIvarDecl**>(&RecFields[0]); 3689 if (ObjCInterfaceDecl *ID = dyn_cast<ObjCInterfaceDecl>(EnclosingDecl)) { 3690 ID->addInstanceVariablesToClass(ClsFields, RecFields.size(), RBrac); 3691 // Must enforce the rule that ivars in the base classes may not be 3692 // duplicates. 3693 if (ID->getSuperClass()) { 3694 for (ObjCInterfaceDecl::ivar_iterator IVI = ID->ivar_begin(), 3695 IVE = ID->ivar_end(); IVI != IVE; ++IVI) { 3696 ObjCIvarDecl* Ivar = (*IVI); 3697 IdentifierInfo *II = Ivar->getIdentifier(); 3698 ObjCIvarDecl* prevIvar = ID->getSuperClass()->lookupInstanceVariable(II); 3699 if (prevIvar) { 3700 Diag(Ivar->getLocation(), diag::err_duplicate_member) << II; 3701 Diag(prevIvar->getLocation(), diag::note_previous_declaration); 3702 } 3703 } 3704 } 3705 } 3706 else if (ObjCImplementationDecl *IMPDecl = 3707 dyn_cast<ObjCImplementationDecl>(EnclosingDecl)) { 3708 assert(IMPDecl && "ActOnFields - missing ObjCImplementationDecl"); 3709 IMPDecl->ObjCAddInstanceVariablesToClassImpl(ClsFields, RecFields.size()); 3710 CheckImplementationIvars(IMPDecl, ClsFields, RecFields.size(), RBrac); 3711 } 3712 } 3713 3714 if (Attr) 3715 ProcessDeclAttributeList(Record, Attr); 3716} 3717 3718Sema::DeclTy *Sema::ActOnEnumConstant(Scope *S, DeclTy *theEnumDecl, 3719 DeclTy *lastEnumConst, 3720 SourceLocation IdLoc, IdentifierInfo *Id, 3721 SourceLocation EqualLoc, ExprTy *val) { 3722 EnumDecl *TheEnumDecl = cast<EnumDecl>(static_cast<Decl*>(theEnumDecl)); 3723 EnumConstantDecl *LastEnumConst = 3724 cast_or_null<EnumConstantDecl>(static_cast<Decl*>(lastEnumConst)); 3725 Expr *Val = static_cast<Expr*>(val); 3726 3727 // The scope passed in may not be a decl scope. Zip up the scope tree until 3728 // we find one that is. 3729 S = getNonFieldDeclScope(S); 3730 3731 // Verify that there isn't already something declared with this name in this 3732 // scope. 3733 NamedDecl *PrevDecl = LookupName(S, Id, LookupOrdinaryName); 3734 if (PrevDecl && PrevDecl->isTemplateParameter()) { 3735 // Maybe we will complain about the shadowed template parameter. 3736 DiagnoseTemplateParameterShadow(IdLoc, PrevDecl); 3737 // Just pretend that we didn't see the previous declaration. 3738 PrevDecl = 0; 3739 } 3740 3741 if (PrevDecl) { 3742 // When in C++, we may get a TagDecl with the same name; in this case the 3743 // enum constant will 'hide' the tag. 3744 assert((getLangOptions().CPlusPlus || !isa<TagDecl>(PrevDecl)) && 3745 "Received TagDecl when not in C++!"); 3746 if (!isa<TagDecl>(PrevDecl) && isDeclInScope(PrevDecl, CurContext, S)) { 3747 if (isa<EnumConstantDecl>(PrevDecl)) 3748 Diag(IdLoc, diag::err_redefinition_of_enumerator) << Id; 3749 else 3750 Diag(IdLoc, diag::err_redefinition) << Id; 3751 Diag(PrevDecl->getLocation(), diag::note_previous_definition); 3752 Val->Destroy(Context); 3753 return 0; 3754 } 3755 } 3756 3757 llvm::APSInt EnumVal(32); 3758 QualType EltTy; 3759 if (Val) { 3760 // Make sure to promote the operand type to int. 3761 UsualUnaryConversions(Val); 3762 3763 // C99 6.7.2.2p2: Make sure we have an integer constant expression. 3764 SourceLocation ExpLoc; 3765 if (VerifyIntegerConstantExpression(Val, &EnumVal)) { 3766 Val->Destroy(Context); 3767 Val = 0; // Just forget about it. 3768 } else { 3769 EltTy = Val->getType(); 3770 } 3771 } 3772 3773 if (!Val) { 3774 if (LastEnumConst) { 3775 // Assign the last value + 1. 3776 EnumVal = LastEnumConst->getInitVal(); 3777 ++EnumVal; 3778 3779 // Check for overflow on increment. 3780 if (EnumVal < LastEnumConst->getInitVal()) 3781 Diag(IdLoc, diag::warn_enum_value_overflow); 3782 3783 EltTy = LastEnumConst->getType(); 3784 } else { 3785 // First value, set to zero. 3786 EltTy = Context.IntTy; 3787 EnumVal.zextOrTrunc(static_cast<uint32_t>(Context.getTypeSize(EltTy))); 3788 } 3789 } 3790 3791 EnumConstantDecl *New = 3792 EnumConstantDecl::Create(Context, TheEnumDecl, IdLoc, Id, EltTy, 3793 Val, EnumVal); 3794 3795 // Register this decl in the current scope stack. 3796 PushOnScopeChains(New, S); 3797 3798 return New; 3799} 3800 3801// FIXME: For consistency with ActOnFields(), we should have the parser 3802// pass in the source location for the left/right braces. 3803void Sema::ActOnEnumBody(SourceLocation EnumLoc, DeclTy *EnumDeclX, 3804 DeclTy **Elements, unsigned NumElements) { 3805 EnumDecl *Enum = cast<EnumDecl>(static_cast<Decl*>(EnumDeclX)); 3806 QualType EnumType = Context.getTypeDeclType(Enum); 3807 3808 // TODO: If the result value doesn't fit in an int, it must be a long or long 3809 // long value. ISO C does not support this, but GCC does as an extension, 3810 // emit a warning. 3811 unsigned IntWidth = Context.Target.getIntWidth(); 3812 3813 // Verify that all the values are okay, compute the size of the values, and 3814 // reverse the list. 3815 unsigned NumNegativeBits = 0; 3816 unsigned NumPositiveBits = 0; 3817 3818 // Keep track of whether all elements have type int. 3819 bool AllElementsInt = true; 3820 3821 for (unsigned i = 0; i != NumElements; ++i) { 3822 EnumConstantDecl *ECD = 3823 cast_or_null<EnumConstantDecl>(static_cast<Decl*>(Elements[i])); 3824 if (!ECD) continue; // Already issued a diagnostic. 3825 3826 // If the enum value doesn't fit in an int, emit an extension warning. 3827 const llvm::APSInt &InitVal = ECD->getInitVal(); 3828 assert(InitVal.getBitWidth() >= IntWidth && 3829 "Should have promoted value to int"); 3830 if (InitVal.getBitWidth() > IntWidth) { 3831 llvm::APSInt V(InitVal); 3832 V.trunc(IntWidth); 3833 V.extend(InitVal.getBitWidth()); 3834 if (V != InitVal) 3835 Diag(ECD->getLocation(), diag::ext_enum_value_not_int) 3836 << InitVal.toString(10); 3837 } 3838 3839 // Keep track of the size of positive and negative values. 3840 if (InitVal.isUnsigned() || InitVal.isNonNegative()) 3841 NumPositiveBits = std::max(NumPositiveBits, 3842 (unsigned)InitVal.getActiveBits()); 3843 else 3844 NumNegativeBits = std::max(NumNegativeBits, 3845 (unsigned)InitVal.getMinSignedBits()); 3846 3847 // Keep track of whether every enum element has type int (very commmon). 3848 if (AllElementsInt) 3849 AllElementsInt = ECD->getType() == Context.IntTy; 3850 } 3851 3852 // Figure out the type that should be used for this enum. 3853 // FIXME: Support attribute(packed) on enums and -fshort-enums. 3854 QualType BestType; 3855 unsigned BestWidth; 3856 3857 if (NumNegativeBits) { 3858 // If there is a negative value, figure out the smallest integer type (of 3859 // int/long/longlong) that fits. 3860 if (NumNegativeBits <= IntWidth && NumPositiveBits < IntWidth) { 3861 BestType = Context.IntTy; 3862 BestWidth = IntWidth; 3863 } else { 3864 BestWidth = Context.Target.getLongWidth(); 3865 3866 if (NumNegativeBits <= BestWidth && NumPositiveBits < BestWidth) 3867 BestType = Context.LongTy; 3868 else { 3869 BestWidth = Context.Target.getLongLongWidth(); 3870 3871 if (NumNegativeBits > BestWidth || NumPositiveBits >= BestWidth) 3872 Diag(Enum->getLocation(), diag::warn_enum_too_large); 3873 BestType = Context.LongLongTy; 3874 } 3875 } 3876 } else { 3877 // If there is no negative value, figure out which of uint, ulong, ulonglong 3878 // fits. 3879 if (NumPositiveBits <= IntWidth) { 3880 BestType = Context.UnsignedIntTy; 3881 BestWidth = IntWidth; 3882 } else if (NumPositiveBits <= 3883 (BestWidth = Context.Target.getLongWidth())) { 3884 BestType = Context.UnsignedLongTy; 3885 } else { 3886 BestWidth = Context.Target.getLongLongWidth(); 3887 assert(NumPositiveBits <= BestWidth && 3888 "How could an initializer get larger than ULL?"); 3889 BestType = Context.UnsignedLongLongTy; 3890 } 3891 } 3892 3893 // Loop over all of the enumerator constants, changing their types to match 3894 // the type of the enum if needed. 3895 for (unsigned i = 0; i != NumElements; ++i) { 3896 EnumConstantDecl *ECD = 3897 cast_or_null<EnumConstantDecl>(static_cast<Decl*>(Elements[i])); 3898 if (!ECD) continue; // Already issued a diagnostic. 3899 3900 // Standard C says the enumerators have int type, but we allow, as an 3901 // extension, the enumerators to be larger than int size. If each 3902 // enumerator value fits in an int, type it as an int, otherwise type it the 3903 // same as the enumerator decl itself. This means that in "enum { X = 1U }" 3904 // that X has type 'int', not 'unsigned'. 3905 if (ECD->getType() == Context.IntTy) { 3906 // Make sure the init value is signed. 3907 llvm::APSInt IV = ECD->getInitVal(); 3908 IV.setIsSigned(true); 3909 ECD->setInitVal(IV); 3910 3911 if (getLangOptions().CPlusPlus) 3912 // C++ [dcl.enum]p4: Following the closing brace of an 3913 // enum-specifier, each enumerator has the type of its 3914 // enumeration. 3915 ECD->setType(EnumType); 3916 continue; // Already int type. 3917 } 3918 3919 // Determine whether the value fits into an int. 3920 llvm::APSInt InitVal = ECD->getInitVal(); 3921 bool FitsInInt; 3922 if (InitVal.isUnsigned() || !InitVal.isNegative()) 3923 FitsInInt = InitVal.getActiveBits() < IntWidth; 3924 else 3925 FitsInInt = InitVal.getMinSignedBits() <= IntWidth; 3926 3927 // If it fits into an integer type, force it. Otherwise force it to match 3928 // the enum decl type. 3929 QualType NewTy; 3930 unsigned NewWidth; 3931 bool NewSign; 3932 if (FitsInInt) { 3933 NewTy = Context.IntTy; 3934 NewWidth = IntWidth; 3935 NewSign = true; 3936 } else if (ECD->getType() == BestType) { 3937 // Already the right type! 3938 if (getLangOptions().CPlusPlus) 3939 // C++ [dcl.enum]p4: Following the closing brace of an 3940 // enum-specifier, each enumerator has the type of its 3941 // enumeration. 3942 ECD->setType(EnumType); 3943 continue; 3944 } else { 3945 NewTy = BestType; 3946 NewWidth = BestWidth; 3947 NewSign = BestType->isSignedIntegerType(); 3948 } 3949 3950 // Adjust the APSInt value. 3951 InitVal.extOrTrunc(NewWidth); 3952 InitVal.setIsSigned(NewSign); 3953 ECD->setInitVal(InitVal); 3954 3955 // Adjust the Expr initializer and type. 3956 if (ECD->getInitExpr()) 3957 ECD->setInitExpr(new (Context) ImplicitCastExpr(NewTy, ECD->getInitExpr(), 3958 /*isLvalue=*/false)); 3959 if (getLangOptions().CPlusPlus) 3960 // C++ [dcl.enum]p4: Following the closing brace of an 3961 // enum-specifier, each enumerator has the type of its 3962 // enumeration. 3963 ECD->setType(EnumType); 3964 else 3965 ECD->setType(NewTy); 3966 } 3967 3968 Enum->completeDefinition(Context, BestType); 3969} 3970 3971Sema::DeclTy *Sema::ActOnFileScopeAsmDecl(SourceLocation Loc, 3972 ExprArg expr) { 3973 StringLiteral *AsmString = cast<StringLiteral>((Expr*)expr.release()); 3974 3975 return FileScopeAsmDecl::Create(Context, CurContext, Loc, AsmString); 3976} 3977 3978 3979void Sema::ActOnPragmaPack(PragmaPackKind Kind, IdentifierInfo *Name, 3980 ExprTy *alignment, SourceLocation PragmaLoc, 3981 SourceLocation LParenLoc, SourceLocation RParenLoc) { 3982 Expr *Alignment = static_cast<Expr *>(alignment); 3983 3984 // If specified then alignment must be a "small" power of two. 3985 unsigned AlignmentVal = 0; 3986 if (Alignment) { 3987 llvm::APSInt Val; 3988 if (!Alignment->isIntegerConstantExpr(Val, Context) || 3989 !Val.isPowerOf2() || 3990 Val.getZExtValue() > 16) { 3991 Diag(PragmaLoc, diag::warn_pragma_pack_invalid_alignment); 3992 Alignment->Destroy(Context); 3993 return; // Ignore 3994 } 3995 3996 AlignmentVal = (unsigned) Val.getZExtValue(); 3997 } 3998 3999 switch (Kind) { 4000 case Action::PPK_Default: // pack([n]) 4001 PackContext.setAlignment(AlignmentVal); 4002 break; 4003 4004 case Action::PPK_Show: // pack(show) 4005 // Show the current alignment, making sure to show the right value 4006 // for the default. 4007 AlignmentVal = PackContext.getAlignment(); 4008 // FIXME: This should come from the target. 4009 if (AlignmentVal == 0) 4010 AlignmentVal = 8; 4011 Diag(PragmaLoc, diag::warn_pragma_pack_show) << AlignmentVal; 4012 break; 4013 4014 case Action::PPK_Push: // pack(push [, id] [, [n]) 4015 PackContext.push(Name); 4016 // Set the new alignment if specified. 4017 if (Alignment) 4018 PackContext.setAlignment(AlignmentVal); 4019 break; 4020 4021 case Action::PPK_Pop: // pack(pop [, id] [, n]) 4022 // MSDN, C/C++ Preprocessor Reference > Pragma Directives > pack: 4023 // "#pragma pack(pop, identifier, n) is undefined" 4024 if (Alignment && Name) 4025 Diag(PragmaLoc, diag::warn_pragma_pack_pop_identifer_and_alignment); 4026 4027 // Do the pop. 4028 if (!PackContext.pop(Name)) { 4029 // If a name was specified then failure indicates the name 4030 // wasn't found. Otherwise failure indicates the stack was 4031 // empty. 4032 Diag(PragmaLoc, diag::warn_pragma_pack_pop_failed) 4033 << (Name ? "no record matching name" : "stack empty"); 4034 4035 // FIXME: Warn about popping named records as MSVC does. 4036 } else { 4037 // Pop succeeded, set the new alignment if specified. 4038 if (Alignment) 4039 PackContext.setAlignment(AlignmentVal); 4040 } 4041 break; 4042 4043 default: 4044 assert(0 && "Invalid #pragma pack kind."); 4045 } 4046} 4047 4048bool PragmaPackStack::pop(IdentifierInfo *Name) { 4049 if (Stack.empty()) 4050 return false; 4051 4052 // If name is empty just pop top. 4053 if (!Name) { 4054 Alignment = Stack.back().first; 4055 Stack.pop_back(); 4056 return true; 4057 } 4058 4059 // Otherwise, find the named record. 4060 for (unsigned i = Stack.size(); i != 0; ) { 4061 --i; 4062 if (Stack[i].second == Name) { 4063 // Found it, pop up to and including this record. 4064 Alignment = Stack[i].first; 4065 Stack.erase(Stack.begin() + i, Stack.end()); 4066 return true; 4067 } 4068 } 4069 4070 return false; 4071} 4072