SemaDecl.cpp revision 1dfa6e15cba39f27a438d63837435596e58af1c1
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/ExprCXX.h" 20#include "clang/Parse/DeclSpec.h" 21#include "clang/Basic/TargetInfo.h" 22#include "clang/Basic/SourceManager.h" 23// FIXME: layering (ideally, Sema shouldn't be dependent on Lex API's) 24#include "clang/Lex/Preprocessor.h" 25#include "clang/Lex/HeaderSearch.h" 26#include "llvm/ADT/SmallSet.h" 27#include "llvm/ADT/STLExtras.h" 28#include <algorithm> 29#include <functional> 30 31using namespace clang; 32 33Sema::TypeTy *Sema::getTypeName(IdentifierInfo &II, Scope *S, 34 const CXXScopeSpec *SS) { 35 Decl *IIDecl = 0; 36 LookupResult Result = LookupParsedName(S, SS, &II, LookupOrdinaryName, false); 37 switch (Result.getKind()) { 38 case LookupResult::NotFound: 39 case LookupResult::FoundOverloaded: 40 case LookupResult::AmbiguousBaseSubobjectTypes: 41 case LookupResult::AmbiguousBaseSubobjects: 42 // FIXME: In the event of an ambiguous lookup, we could visit all of 43 // the entities found to determine whether they are all types. This 44 // might provide better diagnostics. 45 return 0; 46 case LookupResult::Found: 47 IIDecl = Result.getAsDecl(); 48 break; 49 } 50 51 if (IIDecl) { 52 if (isa<TypedefDecl>(IIDecl) || 53 isa<ObjCInterfaceDecl>(IIDecl) || 54 isa<TagDecl>(IIDecl) || 55 isa<TemplateTypeParmDecl>(IIDecl)) 56 return IIDecl; 57 } 58 return 0; 59} 60 61DeclContext *Sema::getContainingDC(DeclContext *DC) { 62 if (CXXMethodDecl *MD = dyn_cast<CXXMethodDecl>(DC)) { 63 // A C++ out-of-line method will return to the file declaration context. 64 if (MD->isOutOfLineDefinition()) 65 return MD->getLexicalDeclContext(); 66 67 // A C++ inline method is parsed *after* the topmost class it was declared in 68 // is fully parsed (it's "complete"). 69 // The parsing of a C++ inline method happens at the declaration context of 70 // the topmost (non-nested) class it is lexically declared in. 71 assert(isa<CXXRecordDecl>(MD->getParent()) && "C++ method not in Record."); 72 DC = MD->getParent(); 73 while (CXXRecordDecl *RD = dyn_cast<CXXRecordDecl>(DC->getLexicalParent())) 74 DC = RD; 75 76 // Return the declaration context of the topmost class the inline method is 77 // declared in. 78 return DC; 79 } 80 81 if (isa<ObjCMethodDecl>(DC)) 82 return Context.getTranslationUnitDecl(); 83 84 if (Decl *D = dyn_cast<Decl>(DC)) 85 return D->getLexicalDeclContext(); 86 87 return DC->getLexicalParent(); 88} 89 90void Sema::PushDeclContext(Scope *S, DeclContext *DC) { 91 assert(getContainingDC(DC) == CurContext && 92 "The next DeclContext should be lexically contained in the current one."); 93 CurContext = DC; 94 S->setEntity(DC); 95} 96 97void Sema::PopDeclContext() { 98 assert(CurContext && "DeclContext imbalance!"); 99 100 CurContext = getContainingDC(CurContext); 101} 102 103/// Add this decl to the scope shadowed decl chains. 104void Sema::PushOnScopeChains(NamedDecl *D, Scope *S) { 105 // Move up the scope chain until we find the nearest enclosing 106 // non-transparent context. The declaration will be introduced into this 107 // scope. 108 while (S->getEntity() && 109 ((DeclContext *)S->getEntity())->isTransparentContext()) 110 S = S->getParent(); 111 112 S->AddDecl(D); 113 114 // Add scoped declarations into their context, so that they can be 115 // found later. Declarations without a context won't be inserted 116 // into any context. 117 CurContext->addDecl(D); 118 119 // C++ [basic.scope]p4: 120 // -- exactly one declaration shall declare a class name or 121 // enumeration name that is not a typedef name and the other 122 // declarations shall all refer to the same object or 123 // enumerator, or all refer to functions and function templates; 124 // in this case the class name or enumeration name is hidden. 125 if (TagDecl *TD = dyn_cast<TagDecl>(D)) { 126 // We are pushing the name of a tag (enum or class). 127 if (CurContext->getLookupContext() 128 == TD->getDeclContext()->getLookupContext()) { 129 // We're pushing the tag into the current context, which might 130 // require some reshuffling in the identifier resolver. 131 IdentifierResolver::iterator 132 I = IdResolver.begin(TD->getDeclName()), 133 IEnd = IdResolver.end(); 134 if (I != IEnd && isDeclInScope(*I, CurContext, S)) { 135 NamedDecl *PrevDecl = *I; 136 for (; I != IEnd && isDeclInScope(*I, CurContext, S); 137 PrevDecl = *I, ++I) { 138 if (TD->declarationReplaces(*I)) { 139 // This is a redeclaration. Remove it from the chain and 140 // break out, so that we'll add in the shadowed 141 // declaration. 142 S->RemoveDecl(*I); 143 if (PrevDecl == *I) { 144 IdResolver.RemoveDecl(*I); 145 IdResolver.AddDecl(TD); 146 return; 147 } else { 148 IdResolver.RemoveDecl(*I); 149 break; 150 } 151 } 152 } 153 154 // There is already a declaration with the same name in the same 155 // scope, which is not a tag declaration. It must be found 156 // before we find the new declaration, so insert the new 157 // declaration at the end of the chain. 158 IdResolver.AddShadowedDecl(TD, PrevDecl); 159 160 return; 161 } 162 } 163 } else if (getLangOptions().CPlusPlus && isa<FunctionDecl>(D)) { 164 // We are pushing the name of a function, which might be an 165 // overloaded name. 166 FunctionDecl *FD = cast<FunctionDecl>(D); 167 IdentifierResolver::iterator Redecl 168 = std::find_if(IdResolver.begin(FD->getDeclName()), 169 IdResolver.end(), 170 std::bind1st(std::mem_fun(&NamedDecl::declarationReplaces), 171 FD)); 172 if (Redecl != IdResolver.end()) { 173 // There is already a declaration of a function on our 174 // IdResolver chain. Replace it with this declaration. 175 S->RemoveDecl(*Redecl); 176 IdResolver.RemoveDecl(*Redecl); 177 } 178 } 179 180 IdResolver.AddDecl(D); 181} 182 183void Sema::ActOnPopScope(SourceLocation Loc, Scope *S) { 184 if (S->decl_empty()) return; 185 assert((S->getFlags() & (Scope::DeclScope | Scope::TemplateParamScope)) && 186 "Scope shouldn't contain decls!"); 187 188 for (Scope::decl_iterator I = S->decl_begin(), E = S->decl_end(); 189 I != E; ++I) { 190 Decl *TmpD = static_cast<Decl*>(*I); 191 assert(TmpD && "This decl didn't get pushed??"); 192 193 assert(isa<NamedDecl>(TmpD) && "Decl isn't NamedDecl?"); 194 NamedDecl *D = cast<NamedDecl>(TmpD); 195 196 if (!D->getDeclName()) continue; 197 198 // Remove this name from our lexical scope. 199 IdResolver.RemoveDecl(D); 200 } 201} 202 203/// getObjCInterfaceDecl - Look up a for a class declaration in the scope. 204/// return 0 if one not found. 205ObjCInterfaceDecl *Sema::getObjCInterfaceDecl(IdentifierInfo *Id) { 206 // The third "scope" argument is 0 since we aren't enabling lazy built-in 207 // creation from this context. 208 Decl *IDecl = LookupName(TUScope, Id, LookupOrdinaryName); 209 210 return dyn_cast_or_null<ObjCInterfaceDecl>(IDecl); 211} 212 213/// getNonFieldDeclScope - Retrieves the innermost scope, starting 214/// from S, where a non-field would be declared. This routine copes 215/// with the difference between C and C++ scoping rules in structs and 216/// unions. For example, the following code is well-formed in C but 217/// ill-formed in C++: 218/// @code 219/// struct S6 { 220/// enum { BAR } e; 221/// }; 222/// 223/// void test_S6() { 224/// struct S6 a; 225/// a.e = BAR; 226/// } 227/// @endcode 228/// For the declaration of BAR, this routine will return a different 229/// scope. The scope S will be the scope of the unnamed enumeration 230/// within S6. In C++, this routine will return the scope associated 231/// with S6, because the enumeration's scope is a transparent 232/// context but structures can contain non-field names. In C, this 233/// routine will return the translation unit scope, since the 234/// enumeration's scope is a transparent context and structures cannot 235/// contain non-field names. 236Scope *Sema::getNonFieldDeclScope(Scope *S) { 237 while (((S->getFlags() & Scope::DeclScope) == 0) || 238 (S->getEntity() && 239 ((DeclContext *)S->getEntity())->isTransparentContext()) || 240 (S->isClassScope() && !getLangOptions().CPlusPlus)) 241 S = S->getParent(); 242 return S; 243} 244 245void Sema::InitBuiltinVaListType() { 246 if (!Context.getBuiltinVaListType().isNull()) 247 return; 248 249 IdentifierInfo *VaIdent = &Context.Idents.get("__builtin_va_list"); 250 Decl *VaDecl = LookupName(TUScope, VaIdent, LookupOrdinaryName); 251 TypedefDecl *VaTypedef = cast<TypedefDecl>(VaDecl); 252 Context.setBuiltinVaListType(Context.getTypedefType(VaTypedef)); 253} 254 255/// LazilyCreateBuiltin - The specified Builtin-ID was first used at file scope. 256/// lazily create a decl for it. 257NamedDecl *Sema::LazilyCreateBuiltin(IdentifierInfo *II, unsigned bid, 258 Scope *S) { 259 Builtin::ID BID = (Builtin::ID)bid; 260 261 if (Context.BuiltinInfo.hasVAListUse(BID)) 262 InitBuiltinVaListType(); 263 264 QualType R = Context.BuiltinInfo.GetBuiltinType(BID, Context); 265 FunctionDecl *New = FunctionDecl::Create(Context, 266 Context.getTranslationUnitDecl(), 267 SourceLocation(), II, R, 268 FunctionDecl::Extern, false); 269 270 // Create Decl objects for each parameter, adding them to the 271 // FunctionDecl. 272 if (FunctionTypeProto *FT = dyn_cast<FunctionTypeProto>(R)) { 273 llvm::SmallVector<ParmVarDecl*, 16> Params; 274 for (unsigned i = 0, e = FT->getNumArgs(); i != e; ++i) 275 Params.push_back(ParmVarDecl::Create(Context, New, SourceLocation(), 0, 276 FT->getArgType(i), VarDecl::None, 0)); 277 New->setParams(Context, &Params[0], Params.size()); 278 } 279 280 281 282 // TUScope is the translation-unit scope to insert this function into. 283 // FIXME: This is hideous. We need to teach PushOnScopeChains to 284 // relate Scopes to DeclContexts, and probably eliminate CurContext 285 // entirely, but we're not there yet. 286 DeclContext *SavedContext = CurContext; 287 CurContext = Context.getTranslationUnitDecl(); 288 PushOnScopeChains(New, TUScope); 289 CurContext = SavedContext; 290 return New; 291} 292 293/// GetStdNamespace - This method gets the C++ "std" namespace. This is where 294/// everything from the standard library is defined. 295NamespaceDecl *Sema::GetStdNamespace() { 296 if (!StdNamespace) { 297 IdentifierInfo *StdIdent = &PP.getIdentifierTable().get("std"); 298 DeclContext *Global = Context.getTranslationUnitDecl(); 299 Decl *Std = LookupQualifiedName(Global, StdIdent, LookupNamespaceName); 300 StdNamespace = dyn_cast_or_null<NamespaceDecl>(Std); 301 } 302 return StdNamespace; 303} 304 305/// MergeTypeDefDecl - We just parsed a typedef 'New' which has the same name 306/// and scope as a previous declaration 'Old'. Figure out how to resolve this 307/// situation, merging decls or emitting diagnostics as appropriate. 308/// 309TypedefDecl *Sema::MergeTypeDefDecl(TypedefDecl *New, Decl *OldD) { 310 bool objc_types = false; 311 // Allow multiple definitions for ObjC built-in typedefs. 312 // FIXME: Verify the underlying types are equivalent! 313 if (getLangOptions().ObjC1) { 314 const IdentifierInfo *TypeID = New->getIdentifier(); 315 switch (TypeID->getLength()) { 316 default: break; 317 case 2: 318 if (!TypeID->isStr("id")) 319 break; 320 Context.setObjCIdType(New); 321 objc_types = true; 322 break; 323 case 5: 324 if (!TypeID->isStr("Class")) 325 break; 326 Context.setObjCClassType(New); 327 objc_types = true; 328 return New; 329 case 3: 330 if (!TypeID->isStr("SEL")) 331 break; 332 Context.setObjCSelType(New); 333 objc_types = true; 334 return New; 335 case 8: 336 if (!TypeID->isStr("Protocol")) 337 break; 338 Context.setObjCProtoType(New->getUnderlyingType()); 339 objc_types = true; 340 return New; 341 } 342 // Fall through - the typedef name was not a builtin type. 343 } 344 // Verify the old decl was also a type. 345 TypeDecl *Old = dyn_cast<TypeDecl>(OldD); 346 if (!Old) { 347 Diag(New->getLocation(), diag::err_redefinition_different_kind) 348 << New->getDeclName(); 349 if (!objc_types) 350 Diag(OldD->getLocation(), diag::note_previous_definition); 351 return New; 352 } 353 354 // Determine the "old" type we'll use for checking and diagnostics. 355 QualType OldType; 356 if (TypedefDecl *OldTypedef = dyn_cast<TypedefDecl>(Old)) 357 OldType = OldTypedef->getUnderlyingType(); 358 else 359 OldType = Context.getTypeDeclType(Old); 360 361 // If the typedef types are not identical, reject them in all languages and 362 // with any extensions enabled. 363 364 if (OldType != New->getUnderlyingType() && 365 Context.getCanonicalType(OldType) != 366 Context.getCanonicalType(New->getUnderlyingType())) { 367 Diag(New->getLocation(), diag::err_redefinition_different_typedef) 368 << New->getUnderlyingType() << OldType; 369 if (!objc_types) 370 Diag(Old->getLocation(), diag::note_previous_definition); 371 return New; 372 } 373 if (objc_types) return New; 374 if (getLangOptions().Microsoft) return New; 375 376 // C++ [dcl.typedef]p2: 377 // In a given non-class scope, a typedef specifier can be used to 378 // redefine the name of any type declared in that scope to refer 379 // to the type to which it already refers. 380 if (getLangOptions().CPlusPlus && !isa<CXXRecordDecl>(CurContext)) 381 return New; 382 383 // In C, redeclaration of a type is a constraint violation (6.7.2.3p1). 384 // Apparently GCC, Intel, and Sun all silently ignore the redeclaration if 385 // *either* declaration is in a system header. The code below implements 386 // this adhoc compatibility rule. FIXME: The following code will not 387 // work properly when compiling ".i" files (containing preprocessed output). 388 if (PP.getDiagnostics().getSuppressSystemWarnings()) { 389 SourceManager &SrcMgr = Context.getSourceManager(); 390 if (SrcMgr.isInSystemHeader(Old->getLocation())) 391 return New; 392 if (SrcMgr.isInSystemHeader(New->getLocation())) 393 return New; 394 } 395 396 Diag(New->getLocation(), diag::err_redefinition) << New->getDeclName(); 397 Diag(Old->getLocation(), diag::note_previous_definition); 398 return New; 399} 400 401/// DeclhasAttr - returns true if decl Declaration already has the target 402/// attribute. 403static bool DeclHasAttr(const Decl *decl, const Attr *target) { 404 for (const Attr *attr = decl->getAttrs(); attr; attr = attr->getNext()) 405 if (attr->getKind() == target->getKind()) 406 return true; 407 408 return false; 409} 410 411/// MergeAttributes - append attributes from the Old decl to the New one. 412static void MergeAttributes(Decl *New, Decl *Old) { 413 Attr *attr = const_cast<Attr*>(Old->getAttrs()), *tmp; 414 415 while (attr) { 416 tmp = attr; 417 attr = attr->getNext(); 418 419 if (!DeclHasAttr(New, tmp)) { 420 tmp->setInherited(true); 421 New->addAttr(tmp); 422 } else { 423 tmp->setNext(0); 424 delete(tmp); 425 } 426 } 427 428 Old->invalidateAttrs(); 429} 430 431/// MergeFunctionDecl - We just parsed a function 'New' from 432/// declarator D which has the same name and scope as a previous 433/// declaration 'Old'. Figure out how to resolve this situation, 434/// merging decls or emitting diagnostics as appropriate. 435/// Redeclaration will be set true if this New is a redeclaration OldD. 436/// 437/// In C++, New and Old must be declarations that are not 438/// overloaded. Use IsOverload to determine whether New and Old are 439/// overloaded, and to select the Old declaration that New should be 440/// merged with. 441FunctionDecl * 442Sema::MergeFunctionDecl(FunctionDecl *New, Decl *OldD, bool &Redeclaration) { 443 assert(!isa<OverloadedFunctionDecl>(OldD) && 444 "Cannot merge with an overloaded function declaration"); 445 446 Redeclaration = false; 447 // Verify the old decl was also a function. 448 FunctionDecl *Old = dyn_cast<FunctionDecl>(OldD); 449 if (!Old) { 450 Diag(New->getLocation(), diag::err_redefinition_different_kind) 451 << New->getDeclName(); 452 Diag(OldD->getLocation(), diag::note_previous_definition); 453 return New; 454 } 455 456 // Determine whether the previous declaration was a definition, 457 // implicit declaration, or a declaration. 458 diag::kind PrevDiag; 459 if (Old->isThisDeclarationADefinition()) 460 PrevDiag = diag::note_previous_definition; 461 else if (Old->isImplicit()) 462 PrevDiag = diag::note_previous_implicit_declaration; 463 else 464 PrevDiag = diag::note_previous_declaration; 465 466 QualType OldQType = Context.getCanonicalType(Old->getType()); 467 QualType NewQType = Context.getCanonicalType(New->getType()); 468 469 if (getLangOptions().CPlusPlus) { 470 // (C++98 13.1p2): 471 // Certain function declarations cannot be overloaded: 472 // -- Function declarations that differ only in the return type 473 // cannot be overloaded. 474 QualType OldReturnType 475 = cast<FunctionType>(OldQType.getTypePtr())->getResultType(); 476 QualType NewReturnType 477 = cast<FunctionType>(NewQType.getTypePtr())->getResultType(); 478 if (OldReturnType != NewReturnType) { 479 Diag(New->getLocation(), diag::err_ovl_diff_return_type); 480 Diag(Old->getLocation(), PrevDiag); 481 Redeclaration = true; 482 return New; 483 } 484 485 const CXXMethodDecl* OldMethod = dyn_cast<CXXMethodDecl>(Old); 486 const CXXMethodDecl* NewMethod = dyn_cast<CXXMethodDecl>(New); 487 if (OldMethod && NewMethod) { 488 // -- Member function declarations with the same name and the 489 // same parameter types cannot be overloaded if any of them 490 // is a static member function declaration. 491 if (OldMethod->isStatic() || NewMethod->isStatic()) { 492 Diag(New->getLocation(), diag::err_ovl_static_nonstatic_member); 493 Diag(Old->getLocation(), PrevDiag); 494 return New; 495 } 496 497 // C++ [class.mem]p1: 498 // [...] A member shall not be declared twice in the 499 // member-specification, except that a nested class or member 500 // class template can be declared and then later defined. 501 if (OldMethod->getLexicalDeclContext() == 502 NewMethod->getLexicalDeclContext()) { 503 unsigned NewDiag; 504 if (isa<CXXConstructorDecl>(OldMethod)) 505 NewDiag = diag::err_constructor_redeclared; 506 else if (isa<CXXDestructorDecl>(NewMethod)) 507 NewDiag = diag::err_destructor_redeclared; 508 else if (isa<CXXConversionDecl>(NewMethod)) 509 NewDiag = diag::err_conv_function_redeclared; 510 else 511 NewDiag = diag::err_member_redeclared; 512 513 Diag(New->getLocation(), NewDiag); 514 Diag(Old->getLocation(), PrevDiag); 515 } 516 } 517 518 // (C++98 8.3.5p3): 519 // All declarations for a function shall agree exactly in both the 520 // return type and the parameter-type-list. 521 if (OldQType == NewQType) { 522 // We have a redeclaration. 523 MergeAttributes(New, Old); 524 Redeclaration = true; 525 return MergeCXXFunctionDecl(New, Old); 526 } 527 528 // Fall through for conflicting redeclarations and redefinitions. 529 } 530 531 // C: Function types need to be compatible, not identical. This handles 532 // duplicate function decls like "void f(int); void f(enum X);" properly. 533 if (!getLangOptions().CPlusPlus && 534 Context.typesAreCompatible(OldQType, NewQType)) { 535 MergeAttributes(New, Old); 536 Redeclaration = true; 537 return New; 538 } 539 540 // A function that has already been declared has been redeclared or defined 541 // with a different type- show appropriate diagnostic 542 543 // TODO: CHECK FOR CONFLICTS, multiple decls with same name in one scope. 544 // TODO: This is totally simplistic. It should handle merging functions 545 // together etc, merging extern int X; int X; ... 546 Diag(New->getLocation(), diag::err_conflicting_types) << New->getDeclName(); 547 Diag(Old->getLocation(), PrevDiag); 548 return New; 549} 550 551/// Predicate for C "tentative" external object definitions (C99 6.9.2). 552static bool isTentativeDefinition(VarDecl *VD) { 553 if (VD->isFileVarDecl()) 554 return (!VD->getInit() && 555 (VD->getStorageClass() == VarDecl::None || 556 VD->getStorageClass() == VarDecl::Static)); 557 return false; 558} 559 560/// CheckForFileScopedRedefinitions - Make sure we forgo redefinition errors 561/// when dealing with C "tentative" external object definitions (C99 6.9.2). 562void Sema::CheckForFileScopedRedefinitions(Scope *S, VarDecl *VD) { 563 bool VDIsTentative = isTentativeDefinition(VD); 564 bool VDIsIncompleteArray = VD->getType()->isIncompleteArrayType(); 565 566 // FIXME: I don't think this will actually see all of the 567 // redefinitions. Can't we check this property on-the-fly? 568 for (IdentifierResolver::iterator I = IdResolver.begin(VD->getIdentifier()), 569 E = IdResolver.end(); 570 I != E; ++I) { 571 if (*I != VD && isDeclInScope(*I, VD->getDeclContext(), S)) { 572 VarDecl *OldDecl = dyn_cast<VarDecl>(*I); 573 574 // Handle the following case: 575 // int a[10]; 576 // int a[]; - the code below makes sure we set the correct type. 577 // int a[11]; - this is an error, size isn't 10. 578 if (OldDecl && VDIsTentative && VDIsIncompleteArray && 579 OldDecl->getType()->isConstantArrayType()) 580 VD->setType(OldDecl->getType()); 581 582 // Check for "tentative" definitions. We can't accomplish this in 583 // MergeVarDecl since the initializer hasn't been attached. 584 if (!OldDecl || isTentativeDefinition(OldDecl) || VDIsTentative) 585 continue; 586 587 // Handle __private_extern__ just like extern. 588 if (OldDecl->getStorageClass() != VarDecl::Extern && 589 OldDecl->getStorageClass() != VarDecl::PrivateExtern && 590 VD->getStorageClass() != VarDecl::Extern && 591 VD->getStorageClass() != VarDecl::PrivateExtern) { 592 Diag(VD->getLocation(), diag::err_redefinition) << VD->getDeclName(); 593 Diag(OldDecl->getLocation(), diag::note_previous_definition); 594 } 595 } 596 } 597} 598 599/// MergeVarDecl - We just parsed a variable 'New' which has the same name 600/// and scope as a previous declaration 'Old'. Figure out how to resolve this 601/// situation, merging decls or emitting diagnostics as appropriate. 602/// 603/// Tentative definition rules (C99 6.9.2p2) are checked by 604/// FinalizeDeclaratorGroup. Unfortunately, we can't analyze tentative 605/// definitions here, since the initializer hasn't been attached. 606/// 607VarDecl *Sema::MergeVarDecl(VarDecl *New, Decl *OldD) { 608 // Verify the old decl was also a variable. 609 VarDecl *Old = dyn_cast<VarDecl>(OldD); 610 if (!Old) { 611 Diag(New->getLocation(), diag::err_redefinition_different_kind) 612 << New->getDeclName(); 613 Diag(OldD->getLocation(), diag::note_previous_definition); 614 return New; 615 } 616 617 MergeAttributes(New, Old); 618 619 // Merge the types 620 QualType MergedT = Context.mergeTypes(New->getType(), Old->getType()); 621 if (MergedT.isNull()) { 622 Diag(New->getLocation(), diag::err_redefinition_different_type) 623 << New->getDeclName(); 624 Diag(Old->getLocation(), diag::note_previous_definition); 625 return New; 626 } 627 New->setType(MergedT); 628 // C99 6.2.2p4: Check if we have a static decl followed by a non-static. 629 if (New->getStorageClass() == VarDecl::Static && 630 (Old->getStorageClass() == VarDecl::None || 631 Old->getStorageClass() == VarDecl::Extern)) { 632 Diag(New->getLocation(), diag::err_static_non_static) << New->getDeclName(); 633 Diag(Old->getLocation(), diag::note_previous_definition); 634 return New; 635 } 636 // C99 6.2.2p4: Check if we have a non-static decl followed by a static. 637 if (New->getStorageClass() != VarDecl::Static && 638 Old->getStorageClass() == VarDecl::Static) { 639 Diag(New->getLocation(), diag::err_non_static_static) << New->getDeclName(); 640 Diag(Old->getLocation(), diag::note_previous_definition); 641 return New; 642 } 643 // Variables with external linkage are analyzed in FinalizeDeclaratorGroup. 644 if (New->getStorageClass() != VarDecl::Extern && !New->isFileVarDecl()) { 645 Diag(New->getLocation(), diag::err_redefinition) << New->getDeclName(); 646 Diag(Old->getLocation(), diag::note_previous_definition); 647 } 648 return New; 649} 650 651/// CheckParmsForFunctionDef - Check that the parameters of the given 652/// function are appropriate for the definition of a function. This 653/// takes care of any checks that cannot be performed on the 654/// declaration itself, e.g., that the types of each of the function 655/// parameters are complete. 656bool Sema::CheckParmsForFunctionDef(FunctionDecl *FD) { 657 bool HasInvalidParm = false; 658 for (unsigned p = 0, NumParams = FD->getNumParams(); p < NumParams; ++p) { 659 ParmVarDecl *Param = FD->getParamDecl(p); 660 661 // C99 6.7.5.3p4: the parameters in a parameter type list in a 662 // function declarator that is part of a function definition of 663 // that function shall not have incomplete type. 664 if (!Param->isInvalidDecl() && 665 DiagnoseIncompleteType(Param->getLocation(), Param->getType(), 666 diag::err_typecheck_decl_incomplete_type)) { 667 Param->setInvalidDecl(); 668 HasInvalidParm = true; 669 } 670 671 // C99 6.9.1p5: If the declarator includes a parameter type list, the 672 // declaration of each parameter shall include an identifier. 673 if (Param->getIdentifier() == 0 && !getLangOptions().CPlusPlus) 674 Diag(Param->getLocation(), diag::err_parameter_name_omitted); 675 } 676 677 return HasInvalidParm; 678} 679 680/// ParsedFreeStandingDeclSpec - This method is invoked when a declspec with 681/// no declarator (e.g. "struct foo;") is parsed. 682Sema::DeclTy *Sema::ParsedFreeStandingDeclSpec(Scope *S, DeclSpec &DS) { 683 TagDecl *Tag 684 = dyn_cast_or_null<TagDecl>(static_cast<Decl *>(DS.getTypeRep())); 685 if (RecordDecl *Record = dyn_cast_or_null<RecordDecl>(Tag)) { 686 if (!Record->getDeclName() && Record->isDefinition() && 687 DS.getStorageClassSpec() != DeclSpec::SCS_typedef) 688 return BuildAnonymousStructOrUnion(S, DS, Record); 689 690 // Microsoft allows unnamed struct/union fields. Don't complain 691 // about them. 692 // FIXME: Should we support Microsoft's extensions in this area? 693 if (Record->getDeclName() && getLangOptions().Microsoft) 694 return Tag; 695 } 696 697 if (!DS.isMissingDeclaratorOk()) { 698 // Warn about typedefs of enums without names, since this is an 699 // extension in both Microsoft an GNU. 700 if (DS.getStorageClassSpec() == DeclSpec::SCS_typedef && 701 Tag && isa<EnumDecl>(Tag)) { 702 Diag(DS.getSourceRange().getBegin(), diag::ext_typedef_without_a_name) 703 << DS.getSourceRange(); 704 return Tag; 705 } 706 707 // FIXME: This diagnostic is emitted even when various previous 708 // errors occurred (see e.g. test/Sema/decl-invalid.c). However, 709 // DeclSpec has no means of communicating this information, and the 710 // responsible parser functions are quite far apart. 711 Diag(DS.getSourceRange().getBegin(), diag::err_no_declarators) 712 << DS.getSourceRange(); 713 return 0; 714 } 715 716 return Tag; 717} 718 719/// InjectAnonymousStructOrUnionMembers - Inject the members of the 720/// anonymous struct or union AnonRecord into the owning context Owner 721/// and scope S. This routine will be invoked just after we realize 722/// that an unnamed union or struct is actually an anonymous union or 723/// struct, e.g., 724/// 725/// @code 726/// union { 727/// int i; 728/// float f; 729/// }; // InjectAnonymousStructOrUnionMembers called here to inject i and 730/// // f into the surrounding scope.x 731/// @endcode 732/// 733/// This routine is recursive, injecting the names of nested anonymous 734/// structs/unions into the owning context and scope as well. 735bool Sema::InjectAnonymousStructOrUnionMembers(Scope *S, DeclContext *Owner, 736 RecordDecl *AnonRecord) { 737 bool Invalid = false; 738 for (RecordDecl::field_iterator F = AnonRecord->field_begin(), 739 FEnd = AnonRecord->field_end(); 740 F != FEnd; ++F) { 741 if ((*F)->getDeclName()) { 742 Decl *PrevDecl = LookupQualifiedName(Owner, (*F)->getDeclName(), 743 LookupOrdinaryName, true); 744 if (PrevDecl && !isa<TagDecl>(PrevDecl)) { 745 // C++ [class.union]p2: 746 // The names of the members of an anonymous union shall be 747 // distinct from the names of any other entity in the 748 // scope in which the anonymous union is declared. 749 unsigned diagKind 750 = AnonRecord->isUnion()? diag::err_anonymous_union_member_redecl 751 : diag::err_anonymous_struct_member_redecl; 752 Diag((*F)->getLocation(), diagKind) 753 << (*F)->getDeclName(); 754 Diag(PrevDecl->getLocation(), diag::note_previous_declaration); 755 Invalid = true; 756 } else { 757 // C++ [class.union]p2: 758 // For the purpose of name lookup, after the anonymous union 759 // definition, the members of the anonymous union are 760 // considered to have been defined in the scope in which the 761 // anonymous union is declared. 762 Owner->makeDeclVisibleInContext(*F); 763 S->AddDecl(*F); 764 IdResolver.AddDecl(*F); 765 } 766 } else if (const RecordType *InnerRecordType 767 = (*F)->getType()->getAsRecordType()) { 768 RecordDecl *InnerRecord = InnerRecordType->getDecl(); 769 if (InnerRecord->isAnonymousStructOrUnion()) 770 Invalid = Invalid || 771 InjectAnonymousStructOrUnionMembers(S, Owner, InnerRecord); 772 } 773 } 774 775 return Invalid; 776} 777 778/// ActOnAnonymousStructOrUnion - Handle the declaration of an 779/// anonymous structure or union. Anonymous unions are a C++ feature 780/// (C++ [class.union]) and a GNU C extension; anonymous structures 781/// are a GNU C and GNU C++ extension. 782Sema::DeclTy *Sema::BuildAnonymousStructOrUnion(Scope *S, DeclSpec &DS, 783 RecordDecl *Record) { 784 DeclContext *Owner = Record->getDeclContext(); 785 786 // Diagnose whether this anonymous struct/union is an extension. 787 if (Record->isUnion() && !getLangOptions().CPlusPlus) 788 Diag(Record->getLocation(), diag::ext_anonymous_union); 789 else if (!Record->isUnion()) 790 Diag(Record->getLocation(), diag::ext_anonymous_struct); 791 792 // C and C++ require different kinds of checks for anonymous 793 // structs/unions. 794 bool Invalid = false; 795 if (getLangOptions().CPlusPlus) { 796 const char* PrevSpec = 0; 797 // C++ [class.union]p3: 798 // Anonymous unions declared in a named namespace or in the 799 // global namespace shall be declared static. 800 if (DS.getStorageClassSpec() != DeclSpec::SCS_static && 801 (isa<TranslationUnitDecl>(Owner) || 802 (isa<NamespaceDecl>(Owner) && 803 cast<NamespaceDecl>(Owner)->getDeclName()))) { 804 Diag(Record->getLocation(), diag::err_anonymous_union_not_static); 805 Invalid = true; 806 807 // Recover by adding 'static'. 808 DS.SetStorageClassSpec(DeclSpec::SCS_static, SourceLocation(), PrevSpec); 809 } 810 // C++ [class.union]p3: 811 // A storage class is not allowed in a declaration of an 812 // anonymous union in a class scope. 813 else if (DS.getStorageClassSpec() != DeclSpec::SCS_unspecified && 814 isa<RecordDecl>(Owner)) { 815 Diag(DS.getStorageClassSpecLoc(), 816 diag::err_anonymous_union_with_storage_spec); 817 Invalid = true; 818 819 // Recover by removing the storage specifier. 820 DS.SetStorageClassSpec(DeclSpec::SCS_unspecified, SourceLocation(), 821 PrevSpec); 822 } 823 824 // C++ [class.union]p2: 825 // The member-specification of an anonymous union shall only 826 // define non-static data members. [Note: nested types and 827 // functions cannot be declared within an anonymous union. ] 828 for (DeclContext::decl_iterator Mem = Record->decls_begin(), 829 MemEnd = Record->decls_end(); 830 Mem != MemEnd; ++Mem) { 831 if (FieldDecl *FD = dyn_cast<FieldDecl>(*Mem)) { 832 // C++ [class.union]p3: 833 // An anonymous union shall not have private or protected 834 // members (clause 11). 835 if (FD->getAccess() == AS_protected || FD->getAccess() == AS_private) { 836 Diag(FD->getLocation(), diag::err_anonymous_record_nonpublic_member) 837 << (int)Record->isUnion() << (int)(FD->getAccess() == AS_protected); 838 Invalid = true; 839 } 840 } else if ((*Mem)->isImplicit()) { 841 // Any implicit members are fine. 842 } else if (RecordDecl *MemRecord = dyn_cast<RecordDecl>(*Mem)) { 843 if (!MemRecord->isAnonymousStructOrUnion() && 844 MemRecord->getDeclName()) { 845 // This is a nested type declaration. 846 Diag(MemRecord->getLocation(), diag::err_anonymous_record_with_type) 847 << (int)Record->isUnion(); 848 Invalid = true; 849 } 850 } else { 851 // We have something that isn't a non-static data 852 // member. Complain about it. 853 unsigned DK = diag::err_anonymous_record_bad_member; 854 if (isa<TypeDecl>(*Mem)) 855 DK = diag::err_anonymous_record_with_type; 856 else if (isa<FunctionDecl>(*Mem)) 857 DK = diag::err_anonymous_record_with_function; 858 else if (isa<VarDecl>(*Mem)) 859 DK = diag::err_anonymous_record_with_static; 860 Diag((*Mem)->getLocation(), DK) 861 << (int)Record->isUnion(); 862 Invalid = true; 863 } 864 } 865 } else { 866 // FIXME: Check GNU C semantics 867 if (Record->isUnion() && !Owner->isRecord()) { 868 Diag(Record->getLocation(), diag::err_anonymous_union_not_member) 869 << (int)getLangOptions().CPlusPlus; 870 Invalid = true; 871 } 872 } 873 874 if (!Record->isUnion() && !Owner->isRecord()) { 875 Diag(Record->getLocation(), diag::err_anonymous_struct_not_member) 876 << (int)getLangOptions().CPlusPlus; 877 Invalid = true; 878 } 879 880 // Create a declaration for this anonymous struct/union. 881 NamedDecl *Anon = 0; 882 if (RecordDecl *OwningClass = dyn_cast<RecordDecl>(Owner)) { 883 Anon = FieldDecl::Create(Context, OwningClass, Record->getLocation(), 884 /*IdentifierInfo=*/0, 885 Context.getTypeDeclType(Record), 886 /*BitWidth=*/0, /*Mutable=*/false); 887 Anon->setAccess(AS_public); 888 if (getLangOptions().CPlusPlus) 889 FieldCollector->Add(cast<FieldDecl>(Anon)); 890 } else { 891 VarDecl::StorageClass SC; 892 switch (DS.getStorageClassSpec()) { 893 default: assert(0 && "Unknown storage class!"); 894 case DeclSpec::SCS_unspecified: SC = VarDecl::None; break; 895 case DeclSpec::SCS_extern: SC = VarDecl::Extern; break; 896 case DeclSpec::SCS_static: SC = VarDecl::Static; break; 897 case DeclSpec::SCS_auto: SC = VarDecl::Auto; break; 898 case DeclSpec::SCS_register: SC = VarDecl::Register; break; 899 case DeclSpec::SCS_private_extern: SC = VarDecl::PrivateExtern; break; 900 case DeclSpec::SCS_mutable: 901 // mutable can only appear on non-static class members, so it's always 902 // an error here 903 Diag(Record->getLocation(), diag::err_mutable_nonmember); 904 Invalid = true; 905 SC = VarDecl::None; 906 break; 907 } 908 909 Anon = VarDecl::Create(Context, Owner, Record->getLocation(), 910 /*IdentifierInfo=*/0, 911 Context.getTypeDeclType(Record), 912 SC, DS.getSourceRange().getBegin()); 913 } 914 Anon->setImplicit(); 915 916 // Add the anonymous struct/union object to the current 917 // context. We'll be referencing this object when we refer to one of 918 // its members. 919 Owner->addDecl(Anon); 920 921 // Inject the members of the anonymous struct/union into the owning 922 // context and into the identifier resolver chain for name lookup 923 // purposes. 924 if (InjectAnonymousStructOrUnionMembers(S, Owner, Record)) 925 Invalid = true; 926 927 // Mark this as an anonymous struct/union type. Note that we do not 928 // do this until after we have already checked and injected the 929 // members of this anonymous struct/union type, because otherwise 930 // the members could be injected twice: once by DeclContext when it 931 // builds its lookup table, and once by 932 // InjectAnonymousStructOrUnionMembers. 933 Record->setAnonymousStructOrUnion(true); 934 935 if (Invalid) 936 Anon->setInvalidDecl(); 937 938 return Anon; 939} 940 941bool Sema::CheckSingleInitializer(Expr *&Init, QualType DeclType, 942 bool DirectInit) { 943 // Get the type before calling CheckSingleAssignmentConstraints(), since 944 // it can promote the expression. 945 QualType InitType = Init->getType(); 946 947 if (getLangOptions().CPlusPlus) { 948 // FIXME: I dislike this error message. A lot. 949 if (PerformImplicitConversion(Init, DeclType, "initializing", DirectInit)) 950 return Diag(Init->getSourceRange().getBegin(), 951 diag::err_typecheck_convert_incompatible) 952 << DeclType << Init->getType() << "initializing" 953 << Init->getSourceRange(); 954 955 return false; 956 } 957 958 AssignConvertType ConvTy = CheckSingleAssignmentConstraints(DeclType, Init); 959 return DiagnoseAssignmentResult(ConvTy, Init->getLocStart(), DeclType, 960 InitType, Init, "initializing"); 961} 962 963bool Sema::CheckStringLiteralInit(StringLiteral *strLiteral, QualType &DeclT) { 964 const ArrayType *AT = Context.getAsArrayType(DeclT); 965 966 if (const IncompleteArrayType *IAT = dyn_cast<IncompleteArrayType>(AT)) { 967 // C99 6.7.8p14. We have an array of character type with unknown size 968 // being initialized to a string literal. 969 llvm::APSInt ConstVal(32); 970 ConstVal = strLiteral->getByteLength() + 1; 971 // Return a new array type (C99 6.7.8p22). 972 DeclT = Context.getConstantArrayType(IAT->getElementType(), ConstVal, 973 ArrayType::Normal, 0); 974 } else { 975 const ConstantArrayType *CAT = cast<ConstantArrayType>(AT); 976 // C99 6.7.8p14. We have an array of character type with known size. 977 // FIXME: Avoid truncation for 64-bit length strings. 978 if (strLiteral->getByteLength() > (unsigned)CAT->getSize().getZExtValue()) 979 Diag(strLiteral->getSourceRange().getBegin(), 980 diag::warn_initializer_string_for_char_array_too_long) 981 << strLiteral->getSourceRange(); 982 } 983 // Set type from "char *" to "constant array of char". 984 strLiteral->setType(DeclT); 985 // For now, we always return false (meaning success). 986 return false; 987} 988 989StringLiteral *Sema::IsStringLiteralInit(Expr *Init, QualType DeclType) { 990 const ArrayType *AT = Context.getAsArrayType(DeclType); 991 if (AT && AT->getElementType()->isCharType()) { 992 return dyn_cast<StringLiteral>(Init->IgnoreParens()); 993 } 994 return 0; 995} 996 997bool Sema::CheckInitializerTypes(Expr *&Init, QualType &DeclType, 998 SourceLocation InitLoc, 999 DeclarationName InitEntity, 1000 bool DirectInit) { 1001 if (DeclType->isDependentType() || Init->isTypeDependent()) 1002 return false; 1003 1004 // C++ [dcl.init.ref]p1: 1005 // A variable declared to be a T&, that is "reference to type T" 1006 // (8.3.2), shall be initialized by an object, or function, of 1007 // type T or by an object that can be converted into a T. 1008 if (DeclType->isReferenceType()) 1009 return CheckReferenceInit(Init, DeclType, 0, false, DirectInit); 1010 1011 // C99 6.7.8p3: The type of the entity to be initialized shall be an array 1012 // of unknown size ("[]") or an object type that is not a variable array type. 1013 if (const VariableArrayType *VAT = Context.getAsVariableArrayType(DeclType)) 1014 return Diag(InitLoc, diag::err_variable_object_no_init) 1015 << VAT->getSizeExpr()->getSourceRange(); 1016 1017 InitListExpr *InitList = dyn_cast<InitListExpr>(Init); 1018 if (!InitList) { 1019 // FIXME: Handle wide strings 1020 if (StringLiteral *strLiteral = IsStringLiteralInit(Init, DeclType)) 1021 return CheckStringLiteralInit(strLiteral, DeclType); 1022 1023 // C++ [dcl.init]p14: 1024 // -- If the destination type is a (possibly cv-qualified) class 1025 // type: 1026 if (getLangOptions().CPlusPlus && DeclType->isRecordType()) { 1027 QualType DeclTypeC = Context.getCanonicalType(DeclType); 1028 QualType InitTypeC = Context.getCanonicalType(Init->getType()); 1029 1030 // -- If the initialization is direct-initialization, or if it is 1031 // copy-initialization where the cv-unqualified version of the 1032 // source type is the same class as, or a derived class of, the 1033 // class of the destination, constructors are considered. 1034 if ((DeclTypeC.getUnqualifiedType() == InitTypeC.getUnqualifiedType()) || 1035 IsDerivedFrom(InitTypeC, DeclTypeC)) { 1036 CXXConstructorDecl *Constructor 1037 = PerformInitializationByConstructor(DeclType, &Init, 1, 1038 InitLoc, Init->getSourceRange(), 1039 InitEntity, 1040 DirectInit? IK_Direct : IK_Copy); 1041 return Constructor == 0; 1042 } 1043 1044 // -- Otherwise (i.e., for the remaining copy-initialization 1045 // cases), user-defined conversion sequences that can 1046 // convert from the source type to the destination type or 1047 // (when a conversion function is used) to a derived class 1048 // thereof are enumerated as described in 13.3.1.4, and the 1049 // best one is chosen through overload resolution 1050 // (13.3). If the conversion cannot be done or is 1051 // ambiguous, the initialization is ill-formed. The 1052 // function selected is called with the initializer 1053 // expression as its argument; if the function is a 1054 // constructor, the call initializes a temporary of the 1055 // destination type. 1056 // FIXME: We're pretending to do copy elision here; return to 1057 // this when we have ASTs for such things. 1058 if (!PerformImplicitConversion(Init, DeclType, "initializing")) 1059 return false; 1060 1061 if (InitEntity) 1062 return Diag(InitLoc, diag::err_cannot_initialize_decl) 1063 << InitEntity << (int)(Init->isLvalue(Context) == Expr::LV_Valid) 1064 << Init->getType() << Init->getSourceRange(); 1065 else 1066 return Diag(InitLoc, diag::err_cannot_initialize_decl_noname) 1067 << DeclType << (int)(Init->isLvalue(Context) == Expr::LV_Valid) 1068 << Init->getType() << Init->getSourceRange(); 1069 } 1070 1071 // C99 6.7.8p16. 1072 if (DeclType->isArrayType()) 1073 return Diag(Init->getLocStart(), diag::err_array_init_list_required) 1074 << Init->getSourceRange(); 1075 1076 return CheckSingleInitializer(Init, DeclType, DirectInit); 1077 } 1078 1079 bool hadError = CheckInitList(InitList, DeclType); 1080 Init = InitList; 1081 return hadError; 1082} 1083 1084/// GetNameForDeclarator - Determine the full declaration name for the 1085/// given Declarator. 1086DeclarationName Sema::GetNameForDeclarator(Declarator &D) { 1087 switch (D.getKind()) { 1088 case Declarator::DK_Abstract: 1089 assert(D.getIdentifier() == 0 && "abstract declarators have no name"); 1090 return DeclarationName(); 1091 1092 case Declarator::DK_Normal: 1093 assert (D.getIdentifier() != 0 && "normal declarators have an identifier"); 1094 return DeclarationName(D.getIdentifier()); 1095 1096 case Declarator::DK_Constructor: { 1097 QualType Ty = Context.getTypeDeclType((TypeDecl *)D.getDeclaratorIdType()); 1098 Ty = Context.getCanonicalType(Ty); 1099 return Context.DeclarationNames.getCXXConstructorName(Ty); 1100 } 1101 1102 case Declarator::DK_Destructor: { 1103 QualType Ty = Context.getTypeDeclType((TypeDecl *)D.getDeclaratorIdType()); 1104 Ty = Context.getCanonicalType(Ty); 1105 return Context.DeclarationNames.getCXXDestructorName(Ty); 1106 } 1107 1108 case Declarator::DK_Conversion: { 1109 QualType Ty = QualType::getFromOpaquePtr(D.getDeclaratorIdType()); 1110 Ty = Context.getCanonicalType(Ty); 1111 return Context.DeclarationNames.getCXXConversionFunctionName(Ty); 1112 } 1113 1114 case Declarator::DK_Operator: 1115 assert(D.getIdentifier() == 0 && "operator names have no identifier"); 1116 return Context.DeclarationNames.getCXXOperatorName( 1117 D.getOverloadedOperator()); 1118 } 1119 1120 assert(false && "Unknown name kind"); 1121 return DeclarationName(); 1122} 1123 1124/// isNearlyMatchingMemberFunction - Determine whether the C++ member 1125/// functions Declaration and Definition are "nearly" matching. This 1126/// heuristic is used to improve diagnostics in the case where an 1127/// out-of-line member function definition doesn't match any 1128/// declaration within the class. 1129static bool isNearlyMatchingMemberFunction(ASTContext &Context, 1130 FunctionDecl *Declaration, 1131 FunctionDecl *Definition) { 1132 if (Declaration->param_size() != Definition->param_size()) 1133 return false; 1134 for (unsigned Idx = 0; Idx < Declaration->param_size(); ++Idx) { 1135 QualType DeclParamTy = Declaration->getParamDecl(Idx)->getType(); 1136 QualType DefParamTy = Definition->getParamDecl(Idx)->getType(); 1137 1138 DeclParamTy = Context.getCanonicalType(DeclParamTy.getNonReferenceType()); 1139 DefParamTy = Context.getCanonicalType(DefParamTy.getNonReferenceType()); 1140 if (DeclParamTy.getUnqualifiedType() != DefParamTy.getUnqualifiedType()) 1141 return false; 1142 } 1143 1144 return true; 1145} 1146 1147Sema::DeclTy * 1148Sema::ActOnDeclarator(Scope *S, Declarator &D, DeclTy *lastDecl, 1149 bool IsFunctionDefinition) { 1150 NamedDecl *LastDeclarator = dyn_cast_or_null<NamedDecl>((Decl *)lastDecl); 1151 DeclarationName Name = GetNameForDeclarator(D); 1152 1153 // All of these full declarators require an identifier. If it doesn't have 1154 // one, the ParsedFreeStandingDeclSpec action should be used. 1155 if (!Name) { 1156 if (!D.getInvalidType()) // Reject this if we think it is valid. 1157 Diag(D.getDeclSpec().getSourceRange().getBegin(), 1158 diag::err_declarator_need_ident) 1159 << D.getDeclSpec().getSourceRange() << D.getSourceRange(); 1160 return 0; 1161 } 1162 1163 // The scope passed in may not be a decl scope. Zip up the scope tree until 1164 // we find one that is. 1165 while ((S->getFlags() & Scope::DeclScope) == 0 || 1166 (S->getFlags() & Scope::TemplateParamScope) != 0) 1167 S = S->getParent(); 1168 1169 DeclContext *DC; 1170 Decl *PrevDecl; 1171 NamedDecl *New; 1172 bool InvalidDecl = false; 1173 1174 // See if this is a redefinition of a variable in the same scope. 1175 if (!D.getCXXScopeSpec().isSet() && !D.getCXXScopeSpec().isInvalid()) { 1176 DC = CurContext; 1177 PrevDecl = LookupName(S, Name, LookupOrdinaryName); 1178 } else { // Something like "int foo::x;" 1179 DC = static_cast<DeclContext*>(D.getCXXScopeSpec().getScopeRep()); 1180 PrevDecl = LookupQualifiedName(DC, Name, LookupOrdinaryName); 1181 1182 // C++ 7.3.1.2p2: 1183 // Members (including explicit specializations of templates) of a named 1184 // namespace can also be defined outside that namespace by explicit 1185 // qualification of the name being defined, provided that the entity being 1186 // defined was already declared in the namespace and the definition appears 1187 // after the point of declaration in a namespace that encloses the 1188 // declarations namespace. 1189 // 1190 // Note that we only check the context at this point. We don't yet 1191 // have enough information to make sure that PrevDecl is actually 1192 // the declaration we want to match. For example, given: 1193 // 1194 // class X { 1195 // void f(); 1196 // void f(float); 1197 // }; 1198 // 1199 // void X::f(int) { } // ill-formed 1200 // 1201 // In this case, PrevDecl will point to the overload set 1202 // containing the two f's declared in X, but neither of them 1203 // matches. 1204 if (!CurContext->Encloses(DC)) { 1205 // The qualifying scope doesn't enclose the original declaration. 1206 // Emit diagnostic based on current scope. 1207 SourceLocation L = D.getIdentifierLoc(); 1208 SourceRange R = D.getCXXScopeSpec().getRange(); 1209 if (isa<FunctionDecl>(CurContext)) { 1210 Diag(L, diag::err_invalid_declarator_in_function) << Name << R; 1211 } else { 1212 Diag(L, diag::err_invalid_declarator_scope) 1213 << Name << cast<NamedDecl>(DC)->getDeclName() << R; 1214 } 1215 InvalidDecl = true; 1216 } 1217 } 1218 1219 if (PrevDecl && PrevDecl->isTemplateParameter()) { 1220 // Maybe we will complain about the shadowed template parameter. 1221 InvalidDecl = InvalidDecl 1222 || DiagnoseTemplateParameterShadow(D.getIdentifierLoc(), PrevDecl); 1223 // Just pretend that we didn't see the previous declaration. 1224 PrevDecl = 0; 1225 } 1226 1227 // In C++, the previous declaration we find might be a tag type 1228 // (class or enum). In this case, the new declaration will hide the 1229 // tag type. Note that this does does not apply if we're declaring a 1230 // typedef (C++ [dcl.typedef]p4). 1231 if (PrevDecl && PrevDecl->getIdentifierNamespace() == Decl::IDNS_Tag && 1232 D.getDeclSpec().getStorageClassSpec() != DeclSpec::SCS_typedef) 1233 PrevDecl = 0; 1234 1235 QualType R = GetTypeForDeclarator(D, S); 1236 assert(!R.isNull() && "GetTypeForDeclarator() returned null type"); 1237 1238 if (D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_typedef) { 1239 New = ActOnTypedefDeclarator(S, D, DC, R, LastDeclarator, PrevDecl, 1240 InvalidDecl); 1241 } else if (R.getTypePtr()->isFunctionType()) { 1242 New = ActOnFunctionDeclarator(S, D, DC, R, LastDeclarator, PrevDecl, 1243 IsFunctionDefinition, InvalidDecl); 1244 } else { 1245 New = ActOnVariableDeclarator(S, D, DC, R, LastDeclarator, PrevDecl, 1246 InvalidDecl); 1247 } 1248 1249 if (New == 0) 1250 return 0; 1251 1252 // Set the lexical context. If the declarator has a C++ scope specifier, the 1253 // lexical context will be different from the semantic context. 1254 New->setLexicalDeclContext(CurContext); 1255 1256 // If this has an identifier, add it to the scope stack. 1257 if (Name) 1258 PushOnScopeChains(New, S); 1259 // If any semantic error occurred, mark the decl as invalid. 1260 if (D.getInvalidType() || InvalidDecl) 1261 New->setInvalidDecl(); 1262 1263 return New; 1264} 1265 1266NamedDecl* 1267Sema::ActOnTypedefDeclarator(Scope* S, Declarator& D, DeclContext* DC, 1268 QualType R, Decl* LastDeclarator, 1269 Decl* PrevDecl, bool& InvalidDecl) { 1270 // Typedef declarators cannot be qualified (C++ [dcl.meaning]p1). 1271 if (D.getCXXScopeSpec().isSet()) { 1272 Diag(D.getIdentifierLoc(), diag::err_qualified_typedef_declarator) 1273 << D.getCXXScopeSpec().getRange(); 1274 InvalidDecl = true; 1275 // Pretend we didn't see the scope specifier. 1276 DC = 0; 1277 } 1278 1279 // Check that there are no default arguments (C++ only). 1280 if (getLangOptions().CPlusPlus) 1281 CheckExtraCXXDefaultArguments(D); 1282 1283 TypedefDecl *NewTD = ParseTypedefDecl(S, D, R, LastDeclarator); 1284 if (!NewTD) return 0; 1285 1286 // Handle attributes prior to checking for duplicates in MergeVarDecl 1287 ProcessDeclAttributes(NewTD, D); 1288 // Merge the decl with the existing one if appropriate. If the decl is 1289 // in an outer scope, it isn't the same thing. 1290 if (PrevDecl && isDeclInScope(PrevDecl, DC, S)) { 1291 NewTD = MergeTypeDefDecl(NewTD, PrevDecl); 1292 if (NewTD == 0) return 0; 1293 } 1294 1295 if (S->getFnParent() == 0) { 1296 // C99 6.7.7p2: If a typedef name specifies a variably modified type 1297 // then it shall have block scope. 1298 if (NewTD->getUnderlyingType()->isVariablyModifiedType()) { 1299 if (NewTD->getUnderlyingType()->isVariableArrayType()) 1300 Diag(D.getIdentifierLoc(), diag::err_vla_decl_in_file_scope); 1301 else 1302 Diag(D.getIdentifierLoc(), diag::err_vm_decl_in_file_scope); 1303 1304 InvalidDecl = true; 1305 } 1306 } 1307 return NewTD; 1308} 1309 1310NamedDecl* 1311Sema::ActOnVariableDeclarator(Scope* S, Declarator& D, DeclContext* DC, 1312 QualType R, Decl* LastDeclarator, 1313 Decl* PrevDecl, bool& InvalidDecl) { 1314 DeclarationName Name = GetNameForDeclarator(D); 1315 1316 // Check that there are no default arguments (C++ only). 1317 if (getLangOptions().CPlusPlus) 1318 CheckExtraCXXDefaultArguments(D); 1319 1320 if (R.getTypePtr()->isObjCInterfaceType()) { 1321 Diag(D.getIdentifierLoc(), diag::err_statically_allocated_object) 1322 << D.getIdentifier(); 1323 InvalidDecl = true; 1324 } 1325 1326 VarDecl *NewVD; 1327 VarDecl::StorageClass SC; 1328 switch (D.getDeclSpec().getStorageClassSpec()) { 1329 default: assert(0 && "Unknown storage class!"); 1330 case DeclSpec::SCS_unspecified: SC = VarDecl::None; break; 1331 case DeclSpec::SCS_extern: SC = VarDecl::Extern; break; 1332 case DeclSpec::SCS_static: SC = VarDecl::Static; break; 1333 case DeclSpec::SCS_auto: SC = VarDecl::Auto; break; 1334 case DeclSpec::SCS_register: SC = VarDecl::Register; break; 1335 case DeclSpec::SCS_private_extern: SC = VarDecl::PrivateExtern; break; 1336 case DeclSpec::SCS_mutable: 1337 // mutable can only appear on non-static class members, so it's always 1338 // an error here 1339 Diag(D.getIdentifierLoc(), diag::err_mutable_nonmember); 1340 InvalidDecl = true; 1341 SC = VarDecl::None; 1342 break; 1343 } 1344 1345 IdentifierInfo *II = Name.getAsIdentifierInfo(); 1346 if (!II) { 1347 Diag(D.getIdentifierLoc(), diag::err_bad_variable_name) 1348 << Name.getAsString(); 1349 return 0; 1350 } 1351 1352 if (DC->isRecord()) { 1353 // This is a static data member for a C++ class. 1354 NewVD = CXXClassVarDecl::Create(Context, cast<CXXRecordDecl>(DC), 1355 D.getIdentifierLoc(), II, 1356 R); 1357 } else { 1358 bool ThreadSpecified = D.getDeclSpec().isThreadSpecified(); 1359 if (S->getFnParent() == 0) { 1360 // C99 6.9p2: The storage-class specifiers auto and register shall not 1361 // appear in the declaration specifiers in an external declaration. 1362 if (SC == VarDecl::Auto || SC == VarDecl::Register) { 1363 Diag(D.getIdentifierLoc(), diag::err_typecheck_sclass_fscope); 1364 InvalidDecl = true; 1365 } 1366 } 1367 NewVD = VarDecl::Create(Context, DC, D.getIdentifierLoc(), 1368 II, R, SC, 1369 // FIXME: Move to DeclGroup... 1370 D.getDeclSpec().getSourceRange().getBegin()); 1371 NewVD->setThreadSpecified(ThreadSpecified); 1372 } 1373 NewVD->setNextDeclarator(LastDeclarator); 1374 1375 // Handle attributes prior to checking for duplicates in MergeVarDecl 1376 ProcessDeclAttributes(NewVD, D); 1377 1378 // Handle GNU asm-label extension (encoded as an attribute). 1379 if (Expr *E = (Expr*) D.getAsmLabel()) { 1380 // The parser guarantees this is a string. 1381 StringLiteral *SE = cast<StringLiteral>(E); 1382 NewVD->addAttr(new AsmLabelAttr(std::string(SE->getStrData(), 1383 SE->getByteLength()))); 1384 } 1385 1386 // Emit an error if an address space was applied to decl with local storage. 1387 // This includes arrays of objects with address space qualifiers, but not 1388 // automatic variables that point to other address spaces. 1389 // ISO/IEC TR 18037 S5.1.2 1390 if (NewVD->hasLocalStorage() && (NewVD->getType().getAddressSpace() != 0)) { 1391 Diag(D.getIdentifierLoc(), diag::err_as_qualified_auto_decl); 1392 InvalidDecl = true; 1393 } 1394 // Merge the decl with the existing one if appropriate. If the decl is 1395 // in an outer scope, it isn't the same thing. 1396 if (PrevDecl && isDeclInScope(PrevDecl, DC, S)) { 1397 if (isa<FieldDecl>(PrevDecl) && D.getCXXScopeSpec().isSet()) { 1398 // The user tried to define a non-static data member 1399 // out-of-line (C++ [dcl.meaning]p1). 1400 Diag(NewVD->getLocation(), diag::err_nonstatic_member_out_of_line) 1401 << D.getCXXScopeSpec().getRange(); 1402 NewVD->Destroy(Context); 1403 return 0; 1404 } 1405 1406 NewVD = MergeVarDecl(NewVD, PrevDecl); 1407 if (NewVD == 0) return 0; 1408 1409 if (D.getCXXScopeSpec().isSet()) { 1410 // No previous declaration in the qualifying scope. 1411 Diag(D.getIdentifierLoc(), diag::err_typecheck_no_member) 1412 << Name << D.getCXXScopeSpec().getRange(); 1413 InvalidDecl = true; 1414 } 1415 } 1416 return NewVD; 1417} 1418 1419NamedDecl* 1420Sema::ActOnFunctionDeclarator(Scope* S, Declarator& D, DeclContext* DC, 1421 QualType R, Decl *LastDeclarator, 1422 Decl* PrevDecl, bool IsFunctionDefinition, 1423 bool& InvalidDecl) { 1424 assert(R.getTypePtr()->isFunctionType()); 1425 1426 DeclarationName Name = GetNameForDeclarator(D); 1427 FunctionDecl::StorageClass SC = FunctionDecl::None; 1428 switch (D.getDeclSpec().getStorageClassSpec()) { 1429 default: assert(0 && "Unknown storage class!"); 1430 case DeclSpec::SCS_auto: 1431 case DeclSpec::SCS_register: 1432 case DeclSpec::SCS_mutable: 1433 Diag(D.getIdentifierLoc(), diag::err_typecheck_sclass_func); 1434 InvalidDecl = true; 1435 break; 1436 case DeclSpec::SCS_unspecified: SC = FunctionDecl::None; break; 1437 case DeclSpec::SCS_extern: SC = FunctionDecl::Extern; break; 1438 case DeclSpec::SCS_static: SC = FunctionDecl::Static; break; 1439 case DeclSpec::SCS_private_extern: SC = FunctionDecl::PrivateExtern;break; 1440 } 1441 1442 bool isInline = D.getDeclSpec().isInlineSpecified(); 1443 // bool isVirtual = D.getDeclSpec().isVirtualSpecified(); 1444 bool isExplicit = D.getDeclSpec().isExplicitSpecified(); 1445 1446 FunctionDecl *NewFD; 1447 if (D.getKind() == Declarator::DK_Constructor) { 1448 // This is a C++ constructor declaration. 1449 assert(DC->isRecord() && 1450 "Constructors can only be declared in a member context"); 1451 1452 InvalidDecl = InvalidDecl || CheckConstructorDeclarator(D, R, SC); 1453 1454 // Create the new declaration 1455 NewFD = CXXConstructorDecl::Create(Context, 1456 cast<CXXRecordDecl>(DC), 1457 D.getIdentifierLoc(), Name, R, 1458 isExplicit, isInline, 1459 /*isImplicitlyDeclared=*/false); 1460 1461 if (InvalidDecl) 1462 NewFD->setInvalidDecl(); 1463 } else if (D.getKind() == Declarator::DK_Destructor) { 1464 // This is a C++ destructor declaration. 1465 if (DC->isRecord()) { 1466 InvalidDecl = InvalidDecl || CheckDestructorDeclarator(D, R, SC); 1467 1468 NewFD = CXXDestructorDecl::Create(Context, 1469 cast<CXXRecordDecl>(DC), 1470 D.getIdentifierLoc(), Name, R, 1471 isInline, 1472 /*isImplicitlyDeclared=*/false); 1473 1474 if (InvalidDecl) 1475 NewFD->setInvalidDecl(); 1476 } else { 1477 Diag(D.getIdentifierLoc(), diag::err_destructor_not_member); 1478 1479 // Create a FunctionDecl to satisfy the function definition parsing 1480 // code path. 1481 NewFD = FunctionDecl::Create(Context, DC, D.getIdentifierLoc(), 1482 Name, R, SC, isInline, 1483 // FIXME: Move to DeclGroup... 1484 D.getDeclSpec().getSourceRange().getBegin()); 1485 InvalidDecl = true; 1486 NewFD->setInvalidDecl(); 1487 } 1488 } else if (D.getKind() == Declarator::DK_Conversion) { 1489 if (!DC->isRecord()) { 1490 Diag(D.getIdentifierLoc(), 1491 diag::err_conv_function_not_member); 1492 return 0; 1493 } else { 1494 InvalidDecl = InvalidDecl || CheckConversionDeclarator(D, R, SC); 1495 1496 NewFD = CXXConversionDecl::Create(Context, cast<CXXRecordDecl>(DC), 1497 D.getIdentifierLoc(), Name, R, 1498 isInline, isExplicit); 1499 1500 if (InvalidDecl) 1501 NewFD->setInvalidDecl(); 1502 } 1503 } else if (DC->isRecord()) { 1504 // This is a C++ method declaration. 1505 NewFD = CXXMethodDecl::Create(Context, cast<CXXRecordDecl>(DC), 1506 D.getIdentifierLoc(), Name, R, 1507 (SC == FunctionDecl::Static), isInline); 1508 } else { 1509 NewFD = FunctionDecl::Create(Context, DC, 1510 D.getIdentifierLoc(), 1511 Name, R, SC, isInline, 1512 // FIXME: Move to DeclGroup... 1513 D.getDeclSpec().getSourceRange().getBegin()); 1514 } 1515 NewFD->setNextDeclarator(LastDeclarator); 1516 1517 // Set the lexical context. If the declarator has a C++ 1518 // scope specifier, the lexical context will be different 1519 // from the semantic context. 1520 NewFD->setLexicalDeclContext(CurContext); 1521 1522 // Handle GNU asm-label extension (encoded as an attribute). 1523 if (Expr *E = (Expr*) D.getAsmLabel()) { 1524 // The parser guarantees this is a string. 1525 StringLiteral *SE = cast<StringLiteral>(E); 1526 NewFD->addAttr(new AsmLabelAttr(std::string(SE->getStrData(), 1527 SE->getByteLength()))); 1528 } 1529 1530 // Copy the parameter declarations from the declarator D to 1531 // the function declaration NewFD, if they are available. 1532 if (D.getNumTypeObjects() > 0) { 1533 DeclaratorChunk::FunctionTypeInfo &FTI = D.getTypeObject(0).Fun; 1534 1535 // Create Decl objects for each parameter, adding them to the 1536 // FunctionDecl. 1537 llvm::SmallVector<ParmVarDecl*, 16> Params; 1538 1539 // Check for C99 6.7.5.3p10 - foo(void) is a non-varargs 1540 // function that takes no arguments, not a function that takes a 1541 // single void argument. 1542 // We let through "const void" here because Sema::GetTypeForDeclarator 1543 // already checks for that case. 1544 if (FTI.NumArgs == 1 && !FTI.isVariadic && FTI.ArgInfo[0].Ident == 0 && 1545 FTI.ArgInfo[0].Param && 1546 ((ParmVarDecl*)FTI.ArgInfo[0].Param)->getType()->isVoidType()) { 1547 // empty arg list, don't push any params. 1548 ParmVarDecl *Param = (ParmVarDecl*)FTI.ArgInfo[0].Param; 1549 1550 // In C++, the empty parameter-type-list must be spelled "void"; a 1551 // typedef of void is not permitted. 1552 if (getLangOptions().CPlusPlus && 1553 Param->getType().getUnqualifiedType() != Context.VoidTy) { 1554 Diag(Param->getLocation(), diag::ext_param_typedef_of_void); 1555 } 1556 } else if (FTI.NumArgs > 0 && FTI.ArgInfo[0].Param != 0) { 1557 for (unsigned i = 0, e = FTI.NumArgs; i != e; ++i) 1558 Params.push_back((ParmVarDecl *)FTI.ArgInfo[i].Param); 1559 } 1560 1561 NewFD->setParams(Context, &Params[0], Params.size()); 1562 } else if (R->getAsTypedefType()) { 1563 // When we're declaring a function with a typedef, as in the 1564 // following example, we'll need to synthesize (unnamed) 1565 // parameters for use in the declaration. 1566 // 1567 // @code 1568 // typedef void fn(int); 1569 // fn f; 1570 // @endcode 1571 const FunctionTypeProto *FT = R->getAsFunctionTypeProto(); 1572 if (!FT) { 1573 // This is a typedef of a function with no prototype, so we 1574 // don't need to do anything. 1575 } else if ((FT->getNumArgs() == 0) || 1576 (FT->getNumArgs() == 1 && !FT->isVariadic() && 1577 FT->getArgType(0)->isVoidType())) { 1578 // This is a zero-argument function. We don't need to do anything. 1579 } else { 1580 // Synthesize a parameter for each argument type. 1581 llvm::SmallVector<ParmVarDecl*, 16> Params; 1582 for (FunctionTypeProto::arg_type_iterator ArgType = FT->arg_type_begin(); 1583 ArgType != FT->arg_type_end(); ++ArgType) { 1584 Params.push_back(ParmVarDecl::Create(Context, DC, 1585 SourceLocation(), 0, 1586 *ArgType, VarDecl::None, 1587 0)); 1588 } 1589 1590 NewFD->setParams(Context, &Params[0], Params.size()); 1591 } 1592 } 1593 1594 if (CXXConstructorDecl *Constructor = dyn_cast<CXXConstructorDecl>(NewFD)) 1595 InvalidDecl = InvalidDecl || CheckConstructor(Constructor); 1596 else if (isa<CXXDestructorDecl>(NewFD)) { 1597 CXXRecordDecl *Record = cast<CXXRecordDecl>(NewFD->getParent()); 1598 Record->setUserDeclaredDestructor(true); 1599 // C++ [class]p4: A POD-struct is an aggregate class that has [...] no 1600 // user-defined destructor. 1601 Record->setPOD(false); 1602 } else if (CXXConversionDecl *Conversion = 1603 dyn_cast<CXXConversionDecl>(NewFD)) 1604 ActOnConversionDeclarator(Conversion); 1605 1606 // Extra checking for C++ overloaded operators (C++ [over.oper]). 1607 if (NewFD->isOverloadedOperator() && 1608 CheckOverloadedOperatorDeclaration(NewFD)) 1609 NewFD->setInvalidDecl(); 1610 1611 // Merge the decl with the existing one if appropriate. Since C functions 1612 // are in a flat namespace, make sure we consider decls in outer scopes. 1613 if (PrevDecl && 1614 (!getLangOptions().CPlusPlus||isDeclInScope(PrevDecl, DC, S))) { 1615 bool Redeclaration = false; 1616 1617 // If C++, determine whether NewFD is an overload of PrevDecl or 1618 // a declaration that requires merging. If it's an overload, 1619 // there's no more work to do here; we'll just add the new 1620 // function to the scope. 1621 OverloadedFunctionDecl::function_iterator MatchedDecl; 1622 if (!getLangOptions().CPlusPlus || 1623 !IsOverload(NewFD, PrevDecl, MatchedDecl)) { 1624 Decl *OldDecl = PrevDecl; 1625 1626 // If PrevDecl was an overloaded function, extract the 1627 // FunctionDecl that matched. 1628 if (isa<OverloadedFunctionDecl>(PrevDecl)) 1629 OldDecl = *MatchedDecl; 1630 1631 // NewFD and PrevDecl represent declarations that need to be 1632 // merged. 1633 NewFD = MergeFunctionDecl(NewFD, OldDecl, Redeclaration); 1634 1635 if (NewFD == 0) return 0; 1636 if (Redeclaration) { 1637 NewFD->setPreviousDeclaration(cast<FunctionDecl>(OldDecl)); 1638 1639 // An out-of-line member function declaration must also be a 1640 // definition (C++ [dcl.meaning]p1). 1641 if (!IsFunctionDefinition && D.getCXXScopeSpec().isSet() && 1642 !InvalidDecl) { 1643 Diag(NewFD->getLocation(), diag::err_out_of_line_declaration) 1644 << D.getCXXScopeSpec().getRange(); 1645 NewFD->setInvalidDecl(); 1646 } 1647 } 1648 } 1649 1650 if (!Redeclaration && D.getCXXScopeSpec().isSet()) { 1651 // The user tried to provide an out-of-line definition for a 1652 // member function, but there was no such member function 1653 // declared (C++ [class.mfct]p2). For example: 1654 // 1655 // class X { 1656 // void f() const; 1657 // }; 1658 // 1659 // void X::f() { } // ill-formed 1660 // 1661 // Complain about this problem, and attempt to suggest close 1662 // matches (e.g., those that differ only in cv-qualifiers and 1663 // whether the parameter types are references). 1664 Diag(D.getIdentifierLoc(), diag::err_member_def_does_not_match) 1665 << cast<CXXRecordDecl>(DC)->getDeclName() 1666 << D.getCXXScopeSpec().getRange(); 1667 InvalidDecl = true; 1668 1669 LookupResult Prev = LookupQualifiedName(DC, Name, LookupOrdinaryName, 1670 true); 1671 assert(!Prev.isAmbiguous() && 1672 "Cannot have an ambiguity in previous-declaration lookup"); 1673 for (LookupResult::iterator Func = Prev.begin(), FuncEnd = Prev.end(); 1674 Func != FuncEnd; ++Func) { 1675 if (isa<CXXMethodDecl>(*Func) && 1676 isNearlyMatchingMemberFunction(Context, cast<FunctionDecl>(*Func), 1677 NewFD)) 1678 Diag((*Func)->getLocation(), diag::note_member_def_close_match); 1679 } 1680 1681 PrevDecl = 0; 1682 } 1683 } 1684 1685 // Handle attributes. We need to have merged decls when handling attributes 1686 // (for example to check for conflicts, etc). 1687 ProcessDeclAttributes(NewFD, D); 1688 1689 if (getLangOptions().CPlusPlus) { 1690 // In C++, check default arguments now that we have merged decls. 1691 CheckCXXDefaultArguments(NewFD); 1692 1693 // An out-of-line member function declaration must also be a 1694 // definition (C++ [dcl.meaning]p1). 1695 if (!IsFunctionDefinition && D.getCXXScopeSpec().isSet() && !InvalidDecl) { 1696 Diag(NewFD->getLocation(), diag::err_out_of_line_declaration) 1697 << D.getCXXScopeSpec().getRange(); 1698 InvalidDecl = true; 1699 } 1700 } 1701 return NewFD; 1702} 1703 1704void Sema::InitializerElementNotConstant(const Expr *Init) { 1705 Diag(Init->getExprLoc(), diag::err_init_element_not_constant) 1706 << Init->getSourceRange(); 1707} 1708 1709bool Sema::CheckAddressConstantExpressionLValue(const Expr* Init) { 1710 switch (Init->getStmtClass()) { 1711 default: 1712 InitializerElementNotConstant(Init); 1713 return true; 1714 case Expr::ParenExprClass: { 1715 const ParenExpr* PE = cast<ParenExpr>(Init); 1716 return CheckAddressConstantExpressionLValue(PE->getSubExpr()); 1717 } 1718 case Expr::CompoundLiteralExprClass: 1719 return cast<CompoundLiteralExpr>(Init)->isFileScope(); 1720 case Expr::DeclRefExprClass: 1721 case Expr::QualifiedDeclRefExprClass: { 1722 const Decl *D = cast<DeclRefExpr>(Init)->getDecl(); 1723 if (const VarDecl *VD = dyn_cast<VarDecl>(D)) { 1724 if (VD->hasGlobalStorage()) 1725 return false; 1726 InitializerElementNotConstant(Init); 1727 return true; 1728 } 1729 if (isa<FunctionDecl>(D)) 1730 return false; 1731 InitializerElementNotConstant(Init); 1732 return true; 1733 } 1734 case Expr::MemberExprClass: { 1735 const MemberExpr *M = cast<MemberExpr>(Init); 1736 if (M->isArrow()) 1737 return CheckAddressConstantExpression(M->getBase()); 1738 return CheckAddressConstantExpressionLValue(M->getBase()); 1739 } 1740 case Expr::ArraySubscriptExprClass: { 1741 // FIXME: Should we pedwarn for "x[0+0]" (where x is a pointer)? 1742 const ArraySubscriptExpr *ASE = cast<ArraySubscriptExpr>(Init); 1743 return CheckAddressConstantExpression(ASE->getBase()) || 1744 CheckArithmeticConstantExpression(ASE->getIdx()); 1745 } 1746 case Expr::StringLiteralClass: 1747 case Expr::PredefinedExprClass: 1748 return false; 1749 case Expr::UnaryOperatorClass: { 1750 const UnaryOperator *Exp = cast<UnaryOperator>(Init); 1751 1752 // C99 6.6p9 1753 if (Exp->getOpcode() == UnaryOperator::Deref) 1754 return CheckAddressConstantExpression(Exp->getSubExpr()); 1755 1756 InitializerElementNotConstant(Init); 1757 return true; 1758 } 1759 } 1760} 1761 1762bool Sema::CheckAddressConstantExpression(const Expr* Init) { 1763 switch (Init->getStmtClass()) { 1764 default: 1765 InitializerElementNotConstant(Init); 1766 return true; 1767 case Expr::ParenExprClass: 1768 return CheckAddressConstantExpression(cast<ParenExpr>(Init)->getSubExpr()); 1769 case Expr::StringLiteralClass: 1770 case Expr::ObjCStringLiteralClass: 1771 return false; 1772 case Expr::CallExprClass: 1773 case Expr::CXXOperatorCallExprClass: 1774 // __builtin___CFStringMakeConstantString is a valid constant l-value. 1775 if (cast<CallExpr>(Init)->isBuiltinCall() == 1776 Builtin::BI__builtin___CFStringMakeConstantString) 1777 return false; 1778 1779 InitializerElementNotConstant(Init); 1780 return true; 1781 1782 case Expr::UnaryOperatorClass: { 1783 const UnaryOperator *Exp = cast<UnaryOperator>(Init); 1784 1785 // C99 6.6p9 1786 if (Exp->getOpcode() == UnaryOperator::AddrOf) 1787 return CheckAddressConstantExpressionLValue(Exp->getSubExpr()); 1788 1789 if (Exp->getOpcode() == UnaryOperator::Extension) 1790 return CheckAddressConstantExpression(Exp->getSubExpr()); 1791 1792 InitializerElementNotConstant(Init); 1793 return true; 1794 } 1795 case Expr::BinaryOperatorClass: { 1796 // FIXME: Should we pedwarn for expressions like "a + 1 + 2"? 1797 const BinaryOperator *Exp = cast<BinaryOperator>(Init); 1798 1799 Expr *PExp = Exp->getLHS(); 1800 Expr *IExp = Exp->getRHS(); 1801 if (IExp->getType()->isPointerType()) 1802 std::swap(PExp, IExp); 1803 1804 // FIXME: Should we pedwarn if IExp isn't an integer constant expression? 1805 return CheckAddressConstantExpression(PExp) || 1806 CheckArithmeticConstantExpression(IExp); 1807 } 1808 case Expr::ImplicitCastExprClass: 1809 case Expr::CStyleCastExprClass: { 1810 const Expr* SubExpr = cast<CastExpr>(Init)->getSubExpr(); 1811 if (Init->getStmtClass() == Expr::ImplicitCastExprClass) { 1812 // Check for implicit promotion 1813 if (SubExpr->getType()->isFunctionType() || 1814 SubExpr->getType()->isArrayType()) 1815 return CheckAddressConstantExpressionLValue(SubExpr); 1816 } 1817 1818 // Check for pointer->pointer cast 1819 if (SubExpr->getType()->isPointerType()) 1820 return CheckAddressConstantExpression(SubExpr); 1821 1822 if (SubExpr->getType()->isIntegralType()) { 1823 // Check for the special-case of a pointer->int->pointer cast; 1824 // this isn't standard, but some code requires it. See 1825 // PR2720 for an example. 1826 if (const CastExpr* SubCast = dyn_cast<CastExpr>(SubExpr)) { 1827 if (SubCast->getSubExpr()->getType()->isPointerType()) { 1828 unsigned IntWidth = Context.getIntWidth(SubCast->getType()); 1829 unsigned PointerWidth = Context.getTypeSize(Context.VoidPtrTy); 1830 if (IntWidth >= PointerWidth) { 1831 return CheckAddressConstantExpression(SubCast->getSubExpr()); 1832 } 1833 } 1834 } 1835 } 1836 if (SubExpr->getType()->isArithmeticType()) { 1837 return CheckArithmeticConstantExpression(SubExpr); 1838 } 1839 1840 InitializerElementNotConstant(Init); 1841 return true; 1842 } 1843 case Expr::ConditionalOperatorClass: { 1844 // FIXME: Should we pedwarn here? 1845 const ConditionalOperator *Exp = cast<ConditionalOperator>(Init); 1846 if (!Exp->getCond()->getType()->isArithmeticType()) { 1847 InitializerElementNotConstant(Init); 1848 return true; 1849 } 1850 if (CheckArithmeticConstantExpression(Exp->getCond())) 1851 return true; 1852 if (Exp->getLHS() && 1853 CheckAddressConstantExpression(Exp->getLHS())) 1854 return true; 1855 return CheckAddressConstantExpression(Exp->getRHS()); 1856 } 1857 case Expr::AddrLabelExprClass: 1858 return false; 1859 } 1860} 1861 1862static const Expr* FindExpressionBaseAddress(const Expr* E); 1863 1864static const Expr* FindExpressionBaseAddressLValue(const Expr* E) { 1865 switch (E->getStmtClass()) { 1866 default: 1867 return E; 1868 case Expr::ParenExprClass: { 1869 const ParenExpr* PE = cast<ParenExpr>(E); 1870 return FindExpressionBaseAddressLValue(PE->getSubExpr()); 1871 } 1872 case Expr::MemberExprClass: { 1873 const MemberExpr *M = cast<MemberExpr>(E); 1874 if (M->isArrow()) 1875 return FindExpressionBaseAddress(M->getBase()); 1876 return FindExpressionBaseAddressLValue(M->getBase()); 1877 } 1878 case Expr::ArraySubscriptExprClass: { 1879 const ArraySubscriptExpr *ASE = cast<ArraySubscriptExpr>(E); 1880 return FindExpressionBaseAddress(ASE->getBase()); 1881 } 1882 case Expr::UnaryOperatorClass: { 1883 const UnaryOperator *Exp = cast<UnaryOperator>(E); 1884 1885 if (Exp->getOpcode() == UnaryOperator::Deref) 1886 return FindExpressionBaseAddress(Exp->getSubExpr()); 1887 1888 return E; 1889 } 1890 } 1891} 1892 1893static const Expr* FindExpressionBaseAddress(const Expr* E) { 1894 switch (E->getStmtClass()) { 1895 default: 1896 return E; 1897 case Expr::ParenExprClass: { 1898 const ParenExpr* PE = cast<ParenExpr>(E); 1899 return FindExpressionBaseAddress(PE->getSubExpr()); 1900 } 1901 case Expr::UnaryOperatorClass: { 1902 const UnaryOperator *Exp = cast<UnaryOperator>(E); 1903 1904 // C99 6.6p9 1905 if (Exp->getOpcode() == UnaryOperator::AddrOf) 1906 return FindExpressionBaseAddressLValue(Exp->getSubExpr()); 1907 1908 if (Exp->getOpcode() == UnaryOperator::Extension) 1909 return FindExpressionBaseAddress(Exp->getSubExpr()); 1910 1911 return E; 1912 } 1913 case Expr::BinaryOperatorClass: { 1914 const BinaryOperator *Exp = cast<BinaryOperator>(E); 1915 1916 Expr *PExp = Exp->getLHS(); 1917 Expr *IExp = Exp->getRHS(); 1918 if (IExp->getType()->isPointerType()) 1919 std::swap(PExp, IExp); 1920 1921 return FindExpressionBaseAddress(PExp); 1922 } 1923 case Expr::ImplicitCastExprClass: { 1924 const Expr* SubExpr = cast<ImplicitCastExpr>(E)->getSubExpr(); 1925 1926 // Check for implicit promotion 1927 if (SubExpr->getType()->isFunctionType() || 1928 SubExpr->getType()->isArrayType()) 1929 return FindExpressionBaseAddressLValue(SubExpr); 1930 1931 // Check for pointer->pointer cast 1932 if (SubExpr->getType()->isPointerType()) 1933 return FindExpressionBaseAddress(SubExpr); 1934 1935 // We assume that we have an arithmetic expression here; 1936 // if we don't, we'll figure it out later 1937 return 0; 1938 } 1939 case Expr::CStyleCastExprClass: { 1940 const Expr* SubExpr = cast<CastExpr>(E)->getSubExpr(); 1941 1942 // Check for pointer->pointer cast 1943 if (SubExpr->getType()->isPointerType()) 1944 return FindExpressionBaseAddress(SubExpr); 1945 1946 // We assume that we have an arithmetic expression here; 1947 // if we don't, we'll figure it out later 1948 return 0; 1949 } 1950 } 1951} 1952 1953bool Sema::CheckArithmeticConstantExpression(const Expr* Init) { 1954 switch (Init->getStmtClass()) { 1955 default: 1956 InitializerElementNotConstant(Init); 1957 return true; 1958 case Expr::ParenExprClass: { 1959 const ParenExpr* PE = cast<ParenExpr>(Init); 1960 return CheckArithmeticConstantExpression(PE->getSubExpr()); 1961 } 1962 case Expr::FloatingLiteralClass: 1963 case Expr::IntegerLiteralClass: 1964 case Expr::CharacterLiteralClass: 1965 case Expr::ImaginaryLiteralClass: 1966 case Expr::TypesCompatibleExprClass: 1967 case Expr::CXXBoolLiteralExprClass: 1968 return false; 1969 case Expr::CallExprClass: 1970 case Expr::CXXOperatorCallExprClass: { 1971 const CallExpr *CE = cast<CallExpr>(Init); 1972 1973 // Allow any constant foldable calls to builtins. 1974 if (CE->isBuiltinCall() && CE->isEvaluatable(Context)) 1975 return false; 1976 1977 InitializerElementNotConstant(Init); 1978 return true; 1979 } 1980 case Expr::DeclRefExprClass: 1981 case Expr::QualifiedDeclRefExprClass: { 1982 const Decl *D = cast<DeclRefExpr>(Init)->getDecl(); 1983 if (isa<EnumConstantDecl>(D)) 1984 return false; 1985 InitializerElementNotConstant(Init); 1986 return true; 1987 } 1988 case Expr::CompoundLiteralExprClass: 1989 // Allow "(vector type){2,4}"; normal C constraints don't allow this, 1990 // but vectors are allowed to be magic. 1991 if (Init->getType()->isVectorType()) 1992 return false; 1993 InitializerElementNotConstant(Init); 1994 return true; 1995 case Expr::UnaryOperatorClass: { 1996 const UnaryOperator *Exp = cast<UnaryOperator>(Init); 1997 1998 switch (Exp->getOpcode()) { 1999 // Address, indirect, pre/post inc/dec, etc are not valid constant exprs. 2000 // See C99 6.6p3. 2001 default: 2002 InitializerElementNotConstant(Init); 2003 return true; 2004 case UnaryOperator::OffsetOf: 2005 if (Exp->getSubExpr()->getType()->isConstantSizeType()) 2006 return false; 2007 InitializerElementNotConstant(Init); 2008 return true; 2009 case UnaryOperator::Extension: 2010 case UnaryOperator::LNot: 2011 case UnaryOperator::Plus: 2012 case UnaryOperator::Minus: 2013 case UnaryOperator::Not: 2014 return CheckArithmeticConstantExpression(Exp->getSubExpr()); 2015 } 2016 } 2017 case Expr::SizeOfAlignOfExprClass: { 2018 const SizeOfAlignOfExpr *Exp = cast<SizeOfAlignOfExpr>(Init); 2019 // Special check for void types, which are allowed as an extension 2020 if (Exp->getTypeOfArgument()->isVoidType()) 2021 return false; 2022 // alignof always evaluates to a constant. 2023 // FIXME: is sizeof(int[3.0]) a constant expression? 2024 if (Exp->isSizeOf() && !Exp->getTypeOfArgument()->isConstantSizeType()) { 2025 InitializerElementNotConstant(Init); 2026 return true; 2027 } 2028 return false; 2029 } 2030 case Expr::BinaryOperatorClass: { 2031 const BinaryOperator *Exp = cast<BinaryOperator>(Init); 2032 2033 if (Exp->getLHS()->getType()->isArithmeticType() && 2034 Exp->getRHS()->getType()->isArithmeticType()) { 2035 return CheckArithmeticConstantExpression(Exp->getLHS()) || 2036 CheckArithmeticConstantExpression(Exp->getRHS()); 2037 } 2038 2039 if (Exp->getLHS()->getType()->isPointerType() && 2040 Exp->getRHS()->getType()->isPointerType()) { 2041 const Expr* LHSBase = FindExpressionBaseAddress(Exp->getLHS()); 2042 const Expr* RHSBase = FindExpressionBaseAddress(Exp->getRHS()); 2043 2044 // Only allow a null (constant integer) base; we could 2045 // allow some additional cases if necessary, but this 2046 // is sufficient to cover offsetof-like constructs. 2047 if (!LHSBase && !RHSBase) { 2048 return CheckAddressConstantExpression(Exp->getLHS()) || 2049 CheckAddressConstantExpression(Exp->getRHS()); 2050 } 2051 } 2052 2053 InitializerElementNotConstant(Init); 2054 return true; 2055 } 2056 case Expr::ImplicitCastExprClass: 2057 case Expr::CStyleCastExprClass: { 2058 const Expr *SubExpr = cast<CastExpr>(Init)->getSubExpr(); 2059 if (SubExpr->getType()->isArithmeticType()) 2060 return CheckArithmeticConstantExpression(SubExpr); 2061 2062 if (SubExpr->getType()->isPointerType()) { 2063 const Expr* Base = FindExpressionBaseAddress(SubExpr); 2064 // If the pointer has a null base, this is an offsetof-like construct 2065 return Base ? false : CheckAddressConstantExpression(SubExpr); 2066 } 2067 2068 InitializerElementNotConstant(Init); 2069 return true; 2070 } 2071 case Expr::ConditionalOperatorClass: { 2072 const ConditionalOperator *Exp = cast<ConditionalOperator>(Init); 2073 2074 // If GNU extensions are disabled, we require all operands to be arithmetic 2075 // constant expressions. 2076 if (getLangOptions().NoExtensions) { 2077 return CheckArithmeticConstantExpression(Exp->getCond()) || 2078 (Exp->getLHS() && CheckArithmeticConstantExpression(Exp->getLHS())) || 2079 CheckArithmeticConstantExpression(Exp->getRHS()); 2080 } 2081 2082 // Otherwise, we have to emulate some of the behavior of fold here. 2083 // Basically GCC treats things like "4 ? 1 : somefunc()" as a constant 2084 // because it can constant fold things away. To retain compatibility with 2085 // GCC code, we see if we can fold the condition to a constant (which we 2086 // should always be able to do in theory). If so, we only require the 2087 // specified arm of the conditional to be a constant. This is a horrible 2088 // hack, but is require by real world code that uses __builtin_constant_p. 2089 Expr::EvalResult EvalResult; 2090 if (!Exp->getCond()->Evaluate(EvalResult, Context) || 2091 EvalResult.HasSideEffects) { 2092 // If Evaluate couldn't fold it, CheckArithmeticConstantExpression 2093 // won't be able to either. Use it to emit the diagnostic though. 2094 bool Res = CheckArithmeticConstantExpression(Exp->getCond()); 2095 assert(Res && "Evaluate couldn't evaluate this constant?"); 2096 return Res; 2097 } 2098 2099 // Verify that the side following the condition is also a constant. 2100 const Expr *TrueSide = Exp->getLHS(), *FalseSide = Exp->getRHS(); 2101 if (EvalResult.Val.getInt() == 0) 2102 std::swap(TrueSide, FalseSide); 2103 2104 if (TrueSide && CheckArithmeticConstantExpression(TrueSide)) 2105 return true; 2106 2107 // Okay, the evaluated side evaluates to a constant, so we accept this. 2108 // Check to see if the other side is obviously not a constant. If so, 2109 // emit a warning that this is a GNU extension. 2110 if (FalseSide && !FalseSide->isEvaluatable(Context)) 2111 Diag(Init->getExprLoc(), 2112 diag::ext_typecheck_expression_not_constant_but_accepted) 2113 << FalseSide->getSourceRange(); 2114 return false; 2115 } 2116 } 2117} 2118 2119bool Sema::CheckForConstantInitializer(Expr *Init, QualType DclT) { 2120 if (DesignatedInitExpr *DIE = dyn_cast<DesignatedInitExpr>(Init)) 2121 Init = DIE->getInit(); 2122 2123 Init = Init->IgnoreParens(); 2124 2125 if (Init->isEvaluatable(Context)) 2126 return false; 2127 2128 // Look through CXXDefaultArgExprs; they have no meaning in this context. 2129 if (CXXDefaultArgExpr* DAE = dyn_cast<CXXDefaultArgExpr>(Init)) 2130 return CheckForConstantInitializer(DAE->getExpr(), DclT); 2131 2132 if (CompoundLiteralExpr *e = dyn_cast<CompoundLiteralExpr>(Init)) 2133 return CheckForConstantInitializer(e->getInitializer(), DclT); 2134 2135 if (isa<ImplicitValueInitExpr>(Init)) { 2136 // FIXME: In C++, check for non-POD types. 2137 return false; 2138 } 2139 2140 if (InitListExpr *Exp = dyn_cast<InitListExpr>(Init)) { 2141 unsigned numInits = Exp->getNumInits(); 2142 for (unsigned i = 0; i < numInits; i++) { 2143 // FIXME: Need to get the type of the declaration for C++, 2144 // because it could be a reference? 2145 2146 if (CheckForConstantInitializer(Exp->getInit(i), 2147 Exp->getInit(i)->getType())) 2148 return true; 2149 } 2150 return false; 2151 } 2152 2153 // FIXME: We can probably remove some of this code below, now that 2154 // Expr::Evaluate is doing the heavy lifting for scalars. 2155 2156 if (Init->isNullPointerConstant(Context)) 2157 return false; 2158 if (Init->getType()->isArithmeticType()) { 2159 QualType InitTy = Context.getCanonicalType(Init->getType()) 2160 .getUnqualifiedType(); 2161 if (InitTy == Context.BoolTy) { 2162 // Special handling for pointers implicitly cast to bool; 2163 // (e.g. "_Bool rr = &rr;"). This is only legal at the top level. 2164 if (ImplicitCastExpr* ICE = dyn_cast<ImplicitCastExpr>(Init)) { 2165 Expr* SubE = ICE->getSubExpr(); 2166 if (SubE->getType()->isPointerType() || 2167 SubE->getType()->isArrayType() || 2168 SubE->getType()->isFunctionType()) { 2169 return CheckAddressConstantExpression(Init); 2170 } 2171 } 2172 } else if (InitTy->isIntegralType()) { 2173 Expr* SubE = 0; 2174 if (CastExpr* CE = dyn_cast<CastExpr>(Init)) 2175 SubE = CE->getSubExpr(); 2176 // Special check for pointer cast to int; we allow as an extension 2177 // an address constant cast to an integer if the integer 2178 // is of an appropriate width (this sort of code is apparently used 2179 // in some places). 2180 // FIXME: Add pedwarn? 2181 // FIXME: Don't allow bitfields here! Need the FieldDecl for that. 2182 if (SubE && (SubE->getType()->isPointerType() || 2183 SubE->getType()->isArrayType() || 2184 SubE->getType()->isFunctionType())) { 2185 unsigned IntWidth = Context.getTypeSize(Init->getType()); 2186 unsigned PointerWidth = Context.getTypeSize(Context.VoidPtrTy); 2187 if (IntWidth >= PointerWidth) 2188 return CheckAddressConstantExpression(Init); 2189 } 2190 } 2191 2192 return CheckArithmeticConstantExpression(Init); 2193 } 2194 2195 if (Init->getType()->isPointerType()) 2196 return CheckAddressConstantExpression(Init); 2197 2198 // An array type at the top level that isn't an init-list must 2199 // be a string literal 2200 if (Init->getType()->isArrayType()) 2201 return false; 2202 2203 if (Init->getType()->isFunctionType()) 2204 return false; 2205 2206 // Allow block exprs at top level. 2207 if (Init->getType()->isBlockPointerType()) 2208 return false; 2209 2210 // GCC cast to union extension 2211 // note: the validity of the cast expr is checked by CheckCastTypes() 2212 if (CastExpr *C = dyn_cast<CastExpr>(Init)) { 2213 QualType T = C->getType(); 2214 return T->isUnionType() && CheckForConstantInitializer(C->getSubExpr(), T); 2215 } 2216 2217 InitializerElementNotConstant(Init); 2218 return true; 2219} 2220 2221void Sema::AddInitializerToDecl(DeclTy *dcl, ExprArg init) { 2222 AddInitializerToDecl(dcl, move(init), /*DirectInit=*/false); 2223} 2224 2225/// AddInitializerToDecl - Adds the initializer Init to the 2226/// declaration dcl. If DirectInit is true, this is C++ direct 2227/// initialization rather than copy initialization. 2228void Sema::AddInitializerToDecl(DeclTy *dcl, ExprArg init, bool DirectInit) { 2229 Decl *RealDecl = static_cast<Decl *>(dcl); 2230 Expr *Init = static_cast<Expr *>(init.release()); 2231 assert(Init && "missing initializer"); 2232 2233 // If there is no declaration, there was an error parsing it. Just ignore 2234 // the initializer. 2235 if (RealDecl == 0) { 2236 delete Init; 2237 return; 2238 } 2239 2240 VarDecl *VDecl = dyn_cast<VarDecl>(RealDecl); 2241 if (!VDecl) { 2242 Diag(RealDecl->getLocation(), diag::err_illegal_initializer); 2243 RealDecl->setInvalidDecl(); 2244 return; 2245 } 2246 // Get the decls type and save a reference for later, since 2247 // CheckInitializerTypes may change it. 2248 QualType DclT = VDecl->getType(), SavT = DclT; 2249 if (VDecl->isBlockVarDecl()) { 2250 VarDecl::StorageClass SC = VDecl->getStorageClass(); 2251 if (SC == VarDecl::Extern) { // C99 6.7.8p5 2252 Diag(VDecl->getLocation(), diag::err_block_extern_cant_init); 2253 VDecl->setInvalidDecl(); 2254 } else if (!VDecl->isInvalidDecl()) { 2255 if (CheckInitializerTypes(Init, DclT, VDecl->getLocation(), 2256 VDecl->getDeclName(), DirectInit)) 2257 VDecl->setInvalidDecl(); 2258 2259 // C++ 3.6.2p2, allow dynamic initialization of static initializers. 2260 if (!getLangOptions().CPlusPlus) { 2261 if (SC == VarDecl::Static) // C99 6.7.8p4. 2262 CheckForConstantInitializer(Init, DclT); 2263 } 2264 } 2265 } else if (VDecl->isFileVarDecl()) { 2266 if (VDecl->getStorageClass() == VarDecl::Extern) 2267 Diag(VDecl->getLocation(), diag::warn_extern_init); 2268 if (!VDecl->isInvalidDecl()) 2269 if (CheckInitializerTypes(Init, DclT, VDecl->getLocation(), 2270 VDecl->getDeclName(), DirectInit)) 2271 VDecl->setInvalidDecl(); 2272 2273 // C++ 3.6.2p2, allow dynamic initialization of static initializers. 2274 if (!getLangOptions().CPlusPlus) { 2275 // C99 6.7.8p4. All file scoped initializers need to be constant. 2276 CheckForConstantInitializer(Init, DclT); 2277 } 2278 } 2279 // If the type changed, it means we had an incomplete type that was 2280 // completed by the initializer. For example: 2281 // int ary[] = { 1, 3, 5 }; 2282 // "ary" transitions from a VariableArrayType to a ConstantArrayType. 2283 if (!VDecl->isInvalidDecl() && (DclT != SavT)) { 2284 VDecl->setType(DclT); 2285 Init->setType(DclT); 2286 } 2287 2288 // Attach the initializer to the decl. 2289 VDecl->setInit(Init); 2290 return; 2291} 2292 2293void Sema::ActOnUninitializedDecl(DeclTy *dcl) { 2294 Decl *RealDecl = static_cast<Decl *>(dcl); 2295 2296 // If there is no declaration, there was an error parsing it. Just ignore it. 2297 if (RealDecl == 0) 2298 return; 2299 2300 if (VarDecl *Var = dyn_cast<VarDecl>(RealDecl)) { 2301 QualType Type = Var->getType(); 2302 // C++ [dcl.init.ref]p3: 2303 // The initializer can be omitted for a reference only in a 2304 // parameter declaration (8.3.5), in the declaration of a 2305 // function return type, in the declaration of a class member 2306 // within its class declaration (9.2), and where the extern 2307 // specifier is explicitly used. 2308 if (Type->isReferenceType() && 2309 Var->getStorageClass() != VarDecl::Extern && 2310 Var->getStorageClass() != VarDecl::PrivateExtern) { 2311 Diag(Var->getLocation(), diag::err_reference_var_requires_init) 2312 << Var->getDeclName() 2313 << SourceRange(Var->getLocation(), Var->getLocation()); 2314 Var->setInvalidDecl(); 2315 return; 2316 } 2317 2318 // C++ [dcl.init]p9: 2319 // 2320 // If no initializer is specified for an object, and the object 2321 // is of (possibly cv-qualified) non-POD class type (or array 2322 // thereof), the object shall be default-initialized; if the 2323 // object is of const-qualified type, the underlying class type 2324 // shall have a user-declared default constructor. 2325 if (getLangOptions().CPlusPlus) { 2326 QualType InitType = Type; 2327 if (const ArrayType *Array = Context.getAsArrayType(Type)) 2328 InitType = Array->getElementType(); 2329 if (Var->getStorageClass() != VarDecl::Extern && 2330 Var->getStorageClass() != VarDecl::PrivateExtern && 2331 InitType->isRecordType()) { 2332 const CXXConstructorDecl *Constructor 2333 = PerformInitializationByConstructor(InitType, 0, 0, 2334 Var->getLocation(), 2335 SourceRange(Var->getLocation(), 2336 Var->getLocation()), 2337 Var->getDeclName(), 2338 IK_Default); 2339 if (!Constructor) 2340 Var->setInvalidDecl(); 2341 } 2342 } 2343 2344#if 0 2345 // FIXME: Temporarily disabled because we are not properly parsing 2346 // linkage specifications on declarations, e.g., 2347 // 2348 // extern "C" const CGPoint CGPointerZero; 2349 // 2350 // C++ [dcl.init]p9: 2351 // 2352 // If no initializer is specified for an object, and the 2353 // object is of (possibly cv-qualified) non-POD class type (or 2354 // array thereof), the object shall be default-initialized; if 2355 // the object is of const-qualified type, the underlying class 2356 // type shall have a user-declared default 2357 // constructor. Otherwise, if no initializer is specified for 2358 // an object, the object and its subobjects, if any, have an 2359 // indeterminate initial value; if the object or any of its 2360 // subobjects are of const-qualified type, the program is 2361 // ill-formed. 2362 // 2363 // This isn't technically an error in C, so we don't diagnose it. 2364 // 2365 // FIXME: Actually perform the POD/user-defined default 2366 // constructor check. 2367 if (getLangOptions().CPlusPlus && 2368 Context.getCanonicalType(Type).isConstQualified() && 2369 Var->getStorageClass() != VarDecl::Extern) 2370 Diag(Var->getLocation(), diag::err_const_var_requires_init) 2371 << Var->getName() 2372 << SourceRange(Var->getLocation(), Var->getLocation()); 2373#endif 2374 } 2375} 2376 2377/// The declarators are chained together backwards, reverse the list. 2378Sema::DeclTy *Sema::FinalizeDeclaratorGroup(Scope *S, DeclTy *group) { 2379 // Often we have single declarators, handle them quickly. 2380 Decl *GroupDecl = static_cast<Decl*>(group); 2381 if (GroupDecl == 0) 2382 return 0; 2383 2384 Decl *Group = dyn_cast<Decl>(GroupDecl); 2385 Decl *NewGroup = 0; 2386 if (Group->getNextDeclarator() == 0) 2387 NewGroup = Group; 2388 else { // reverse the list. 2389 while (Group) { 2390 Decl *Next = Group->getNextDeclarator(); 2391 Group->setNextDeclarator(NewGroup); 2392 NewGroup = Group; 2393 Group = Next; 2394 } 2395 } 2396 // Perform semantic analysis that depends on having fully processed both 2397 // the declarator and initializer. 2398 for (Decl *ID = NewGroup; ID; ID = ID->getNextDeclarator()) { 2399 VarDecl *IDecl = dyn_cast<VarDecl>(ID); 2400 if (!IDecl) 2401 continue; 2402 QualType T = IDecl->getType(); 2403 2404 if (T->isVariableArrayType()) { 2405 const VariableArrayType *VAT = Context.getAsVariableArrayType(T); 2406 2407 // FIXME: This won't give the correct result for 2408 // int a[10][n]; 2409 SourceRange SizeRange = VAT->getSizeExpr()->getSourceRange(); 2410 if (IDecl->isFileVarDecl()) { 2411 Diag(IDecl->getLocation(), diag::err_vla_decl_in_file_scope) << 2412 SizeRange; 2413 2414 IDecl->setInvalidDecl(); 2415 } else { 2416 // C99 6.7.5.2p2: If an identifier is declared to be an object with 2417 // static storage duration, it shall not have a variable length array. 2418 if (IDecl->getStorageClass() == VarDecl::Static) { 2419 Diag(IDecl->getLocation(), diag::err_vla_decl_has_static_storage) 2420 << SizeRange; 2421 IDecl->setInvalidDecl(); 2422 } else if (IDecl->getStorageClass() == VarDecl::Extern) { 2423 Diag(IDecl->getLocation(), diag::err_vla_decl_has_extern_linkage) 2424 << SizeRange; 2425 IDecl->setInvalidDecl(); 2426 } 2427 } 2428 } else if (T->isVariablyModifiedType()) { 2429 if (IDecl->isFileVarDecl()) { 2430 Diag(IDecl->getLocation(), diag::err_vm_decl_in_file_scope); 2431 IDecl->setInvalidDecl(); 2432 } else { 2433 if (IDecl->getStorageClass() == VarDecl::Extern) { 2434 Diag(IDecl->getLocation(), diag::err_vm_decl_has_extern_linkage); 2435 IDecl->setInvalidDecl(); 2436 } 2437 } 2438 } 2439 2440 // Block scope. C99 6.7p7: If an identifier for an object is declared with 2441 // no linkage (C99 6.2.2p6), the type for the object shall be complete... 2442 if (IDecl->isBlockVarDecl() && 2443 IDecl->getStorageClass() != VarDecl::Extern) { 2444 if (!IDecl->isInvalidDecl() && 2445 DiagnoseIncompleteType(IDecl->getLocation(), T, 2446 diag::err_typecheck_decl_incomplete_type)) 2447 IDecl->setInvalidDecl(); 2448 } 2449 // File scope. C99 6.9.2p2: A declaration of an identifier for and 2450 // object that has file scope without an initializer, and without a 2451 // storage-class specifier or with the storage-class specifier "static", 2452 // constitutes a tentative definition. Note: A tentative definition with 2453 // external linkage is valid (C99 6.2.2p5). 2454 if (isTentativeDefinition(IDecl)) { 2455 if (T->isIncompleteArrayType()) { 2456 // C99 6.9.2 (p2, p5): Implicit initialization causes an incomplete 2457 // array to be completed. Don't issue a diagnostic. 2458 } else if (!IDecl->isInvalidDecl() && 2459 DiagnoseIncompleteType(IDecl->getLocation(), T, 2460 diag::err_typecheck_decl_incomplete_type)) 2461 // C99 6.9.2p3: If the declaration of an identifier for an object is 2462 // a tentative definition and has internal linkage (C99 6.2.2p3), the 2463 // declared type shall not be an incomplete type. 2464 IDecl->setInvalidDecl(); 2465 } 2466 if (IDecl->isFileVarDecl()) 2467 CheckForFileScopedRedefinitions(S, IDecl); 2468 } 2469 return NewGroup; 2470} 2471 2472/// ActOnParamDeclarator - Called from Parser::ParseFunctionDeclarator() 2473/// to introduce parameters into function prototype scope. 2474Sema::DeclTy * 2475Sema::ActOnParamDeclarator(Scope *S, Declarator &D) { 2476 const DeclSpec &DS = D.getDeclSpec(); 2477 2478 // Verify C99 6.7.5.3p2: The only SCS allowed is 'register'. 2479 VarDecl::StorageClass StorageClass = VarDecl::None; 2480 if (DS.getStorageClassSpec() == DeclSpec::SCS_register) { 2481 StorageClass = VarDecl::Register; 2482 } else if (DS.getStorageClassSpec() != DeclSpec::SCS_unspecified) { 2483 Diag(DS.getStorageClassSpecLoc(), 2484 diag::err_invalid_storage_class_in_func_decl); 2485 D.getMutableDeclSpec().ClearStorageClassSpecs(); 2486 } 2487 if (DS.isThreadSpecified()) { 2488 Diag(DS.getThreadSpecLoc(), 2489 diag::err_invalid_storage_class_in_func_decl); 2490 D.getMutableDeclSpec().ClearStorageClassSpecs(); 2491 } 2492 2493 // Check that there are no default arguments inside the type of this 2494 // parameter (C++ only). 2495 if (getLangOptions().CPlusPlus) 2496 CheckExtraCXXDefaultArguments(D); 2497 2498 // In this context, we *do not* check D.getInvalidType(). If the declarator 2499 // type was invalid, GetTypeForDeclarator() still returns a "valid" type, 2500 // though it will not reflect the user specified type. 2501 QualType parmDeclType = GetTypeForDeclarator(D, S); 2502 2503 assert(!parmDeclType.isNull() && "GetTypeForDeclarator() returned null type"); 2504 2505 // TODO: CHECK FOR CONFLICTS, multiple decls with same name in one scope. 2506 // Can this happen for params? We already checked that they don't conflict 2507 // among each other. Here they can only shadow globals, which is ok. 2508 IdentifierInfo *II = D.getIdentifier(); 2509 if (II) { 2510 if (Decl *PrevDecl = LookupName(S, II, LookupOrdinaryName)) { 2511 if (PrevDecl->isTemplateParameter()) { 2512 // Maybe we will complain about the shadowed template parameter. 2513 DiagnoseTemplateParameterShadow(D.getIdentifierLoc(), PrevDecl); 2514 // Just pretend that we didn't see the previous declaration. 2515 PrevDecl = 0; 2516 } else if (S->isDeclScope(PrevDecl)) { 2517 Diag(D.getIdentifierLoc(), diag::err_param_redefinition) << II; 2518 2519 // Recover by removing the name 2520 II = 0; 2521 D.SetIdentifier(0, D.getIdentifierLoc()); 2522 } 2523 } 2524 } 2525 2526 // Perform the default function/array conversion (C99 6.7.5.3p[7,8]). 2527 // Doing the promotion here has a win and a loss. The win is the type for 2528 // both Decl's and DeclRefExpr's will match (a convenient invariant for the 2529 // code generator). The loss is the orginal type isn't preserved. For example: 2530 // 2531 // void func(int parmvardecl[5]) { // convert "int [5]" to "int *" 2532 // int blockvardecl[5]; 2533 // sizeof(parmvardecl); // size == 4 2534 // sizeof(blockvardecl); // size == 20 2535 // } 2536 // 2537 // For expressions, all implicit conversions are captured using the 2538 // ImplicitCastExpr AST node (we have no such mechanism for Decl's). 2539 // 2540 // FIXME: If a source translation tool needs to see the original type, then 2541 // we need to consider storing both types (in ParmVarDecl)... 2542 // 2543 if (parmDeclType->isArrayType()) { 2544 // int x[restrict 4] -> int *restrict 2545 parmDeclType = Context.getArrayDecayedType(parmDeclType); 2546 } else if (parmDeclType->isFunctionType()) 2547 parmDeclType = Context.getPointerType(parmDeclType); 2548 2549 ParmVarDecl *New = ParmVarDecl::Create(Context, CurContext, 2550 D.getIdentifierLoc(), II, 2551 parmDeclType, StorageClass, 2552 0); 2553 2554 if (D.getInvalidType()) 2555 New->setInvalidDecl(); 2556 2557 // Parameter declarators cannot be qualified (C++ [dcl.meaning]p1). 2558 if (D.getCXXScopeSpec().isSet()) { 2559 Diag(D.getIdentifierLoc(), diag::err_qualified_param_declarator) 2560 << D.getCXXScopeSpec().getRange(); 2561 New->setInvalidDecl(); 2562 } 2563 2564 // Add the parameter declaration into this scope. 2565 S->AddDecl(New); 2566 if (II) 2567 IdResolver.AddDecl(New); 2568 2569 ProcessDeclAttributes(New, D); 2570 return New; 2571 2572} 2573 2574void Sema::ActOnFinishKNRParamDeclarations(Scope *S, Declarator &D) { 2575 assert(D.getTypeObject(0).Kind == DeclaratorChunk::Function && 2576 "Not a function declarator!"); 2577 DeclaratorChunk::FunctionTypeInfo &FTI = D.getTypeObject(0).Fun; 2578 2579 // Verify 6.9.1p6: 'every identifier in the identifier list shall be declared' 2580 // for a K&R function. 2581 if (!FTI.hasPrototype) { 2582 for (unsigned i = 0, e = FTI.NumArgs; i != e; ++i) { 2583 if (FTI.ArgInfo[i].Param == 0) { 2584 Diag(FTI.ArgInfo[i].IdentLoc, diag::ext_param_not_declared) 2585 << FTI.ArgInfo[i].Ident; 2586 // Implicitly declare the argument as type 'int' for lack of a better 2587 // type. 2588 DeclSpec DS; 2589 const char* PrevSpec; // unused 2590 DS.SetTypeSpecType(DeclSpec::TST_int, FTI.ArgInfo[i].IdentLoc, 2591 PrevSpec); 2592 Declarator ParamD(DS, Declarator::KNRTypeListContext); 2593 ParamD.SetIdentifier(FTI.ArgInfo[i].Ident, FTI.ArgInfo[i].IdentLoc); 2594 FTI.ArgInfo[i].Param = ActOnParamDeclarator(S, ParamD); 2595 } 2596 } 2597 } 2598} 2599 2600Sema::DeclTy *Sema::ActOnStartOfFunctionDef(Scope *FnBodyScope, Declarator &D) { 2601 assert(getCurFunctionDecl() == 0 && "Function parsing confused"); 2602 assert(D.getTypeObject(0).Kind == DeclaratorChunk::Function && 2603 "Not a function declarator!"); 2604 DeclaratorChunk::FunctionTypeInfo &FTI = D.getTypeObject(0).Fun; 2605 2606 if (FTI.hasPrototype) { 2607 // FIXME: Diagnose arguments without names in C. 2608 } 2609 2610 Scope *ParentScope = FnBodyScope->getParent(); 2611 2612 return ActOnStartOfFunctionDef(FnBodyScope, 2613 ActOnDeclarator(ParentScope, D, 0, 2614 /*IsFunctionDefinition=*/true)); 2615} 2616 2617Sema::DeclTy *Sema::ActOnStartOfFunctionDef(Scope *FnBodyScope, DeclTy *D) { 2618 Decl *decl = static_cast<Decl*>(D); 2619 FunctionDecl *FD = cast<FunctionDecl>(decl); 2620 2621 // See if this is a redefinition. 2622 const FunctionDecl *Definition; 2623 if (FD->getBody(Definition)) { 2624 Diag(FD->getLocation(), diag::err_redefinition) << FD->getDeclName(); 2625 Diag(Definition->getLocation(), diag::note_previous_definition); 2626 } 2627 2628 PushDeclContext(FnBodyScope, FD); 2629 2630 // Check the validity of our function parameters 2631 CheckParmsForFunctionDef(FD); 2632 2633 // Introduce our parameters into the function scope 2634 for (unsigned p = 0, NumParams = FD->getNumParams(); p < NumParams; ++p) { 2635 ParmVarDecl *Param = FD->getParamDecl(p); 2636 Param->setOwningFunction(FD); 2637 2638 // If this has an identifier, add it to the scope stack. 2639 if (Param->getIdentifier()) 2640 PushOnScopeChains(Param, FnBodyScope); 2641 } 2642 2643 // Checking attributes of current function definition 2644 // dllimport attribute. 2645 if (FD->getAttr<DLLImportAttr>() && (!FD->getAttr<DLLExportAttr>())) { 2646 // dllimport attribute cannot be applied to definition. 2647 if (!(FD->getAttr<DLLImportAttr>())->isInherited()) { 2648 Diag(FD->getLocation(), 2649 diag::err_attribute_can_be_applied_only_to_symbol_declaration) 2650 << "dllimport"; 2651 FD->setInvalidDecl(); 2652 return FD; 2653 } else { 2654 // If a symbol previously declared dllimport is later defined, the 2655 // attribute is ignored in subsequent references, and a warning is 2656 // emitted. 2657 Diag(FD->getLocation(), 2658 diag::warn_redeclaration_without_attribute_prev_attribute_ignored) 2659 << FD->getNameAsCString() << "dllimport"; 2660 } 2661 } 2662 return FD; 2663} 2664 2665Sema::DeclTy *Sema::ActOnFinishFunctionBody(DeclTy *D, StmtArg BodyArg) { 2666 Decl *dcl = static_cast<Decl *>(D); 2667 Stmt *Body = static_cast<Stmt*>(BodyArg.release()); 2668 if (FunctionDecl *FD = dyn_cast_or_null<FunctionDecl>(dcl)) { 2669 FD->setBody(Body); 2670 assert(FD == getCurFunctionDecl() && "Function parsing confused"); 2671 } else if (ObjCMethodDecl *MD = dyn_cast_or_null<ObjCMethodDecl>(dcl)) { 2672 MD->setBody((Stmt*)Body); 2673 } else 2674 return 0; 2675 PopDeclContext(); 2676 // Verify and clean out per-function state. 2677 2678 // Check goto/label use. 2679 for (llvm::DenseMap<IdentifierInfo*, LabelStmt*>::iterator 2680 I = LabelMap.begin(), E = LabelMap.end(); I != E; ++I) { 2681 // Verify that we have no forward references left. If so, there was a goto 2682 // or address of a label taken, but no definition of it. Label fwd 2683 // definitions are indicated with a null substmt. 2684 if (I->second->getSubStmt() == 0) { 2685 LabelStmt *L = I->second; 2686 // Emit error. 2687 Diag(L->getIdentLoc(), diag::err_undeclared_label_use) << L->getName(); 2688 2689 // At this point, we have gotos that use the bogus label. Stitch it into 2690 // the function body so that they aren't leaked and that the AST is well 2691 // formed. 2692 if (Body) { 2693 L->setSubStmt(new NullStmt(L->getIdentLoc())); 2694 cast<CompoundStmt>(Body)->push_back(L); 2695 } else { 2696 // The whole function wasn't parsed correctly, just delete this. 2697 delete L; 2698 } 2699 } 2700 } 2701 LabelMap.clear(); 2702 2703 return D; 2704} 2705 2706/// ImplicitlyDefineFunction - An undeclared identifier was used in a function 2707/// call, forming a call to an implicitly defined function (per C99 6.5.1p2). 2708NamedDecl *Sema::ImplicitlyDefineFunction(SourceLocation Loc, 2709 IdentifierInfo &II, Scope *S) { 2710 // Extension in C99. Legal in C90, but warn about it. 2711 if (getLangOptions().C99) 2712 Diag(Loc, diag::ext_implicit_function_decl) << &II; 2713 else 2714 Diag(Loc, diag::warn_implicit_function_decl) << &II; 2715 2716 // FIXME: handle stuff like: 2717 // void foo() { extern float X(); } 2718 // void bar() { X(); } <-- implicit decl for X in another scope. 2719 2720 // Set a Declarator for the implicit definition: int foo(); 2721 const char *Dummy; 2722 DeclSpec DS; 2723 bool Error = DS.SetTypeSpecType(DeclSpec::TST_int, Loc, Dummy); 2724 Error = Error; // Silence warning. 2725 assert(!Error && "Error setting up implicit decl!"); 2726 Declarator D(DS, Declarator::BlockContext); 2727 D.AddTypeInfo(DeclaratorChunk::getFunction(false, false, 0, 0, 0, Loc, D)); 2728 D.SetIdentifier(&II, Loc); 2729 2730 // Insert this function into translation-unit scope. 2731 2732 DeclContext *PrevDC = CurContext; 2733 CurContext = Context.getTranslationUnitDecl(); 2734 2735 FunctionDecl *FD = 2736 dyn_cast<FunctionDecl>(static_cast<Decl*>(ActOnDeclarator(TUScope, D, 0))); 2737 FD->setImplicit(); 2738 2739 CurContext = PrevDC; 2740 2741 return FD; 2742} 2743 2744 2745TypedefDecl *Sema::ParseTypedefDecl(Scope *S, Declarator &D, QualType T, 2746 Decl *LastDeclarator) { 2747 assert(D.getIdentifier() && "Wrong callback for declspec without declarator"); 2748 assert(!T.isNull() && "GetTypeForDeclarator() returned null type"); 2749 2750 // Scope manipulation handled by caller. 2751 TypedefDecl *NewTD = TypedefDecl::Create(Context, CurContext, 2752 D.getIdentifierLoc(), 2753 D.getIdentifier(), 2754 T); 2755 NewTD->setNextDeclarator(LastDeclarator); 2756 if (D.getInvalidType()) 2757 NewTD->setInvalidDecl(); 2758 return NewTD; 2759} 2760 2761/// ActOnTag - This is invoked when we see 'struct foo' or 'struct {'. In the 2762/// former case, Name will be non-null. In the later case, Name will be null. 2763/// TagSpec indicates what kind of tag this is. TK indicates whether this is a 2764/// reference/declaration/definition of a tag. 2765Sema::DeclTy *Sema::ActOnTag(Scope *S, unsigned TagSpec, TagKind TK, 2766 SourceLocation KWLoc, const CXXScopeSpec &SS, 2767 IdentifierInfo *Name, SourceLocation NameLoc, 2768 AttributeList *Attr, 2769 MultiTemplateParamsArg TemplateParameterLists) { 2770 // If this is not a definition, it must have a name. 2771 assert((Name != 0 || TK == TK_Definition) && 2772 "Nameless record must be a definition!"); 2773 2774 TagDecl::TagKind Kind; 2775 switch (TagSpec) { 2776 default: assert(0 && "Unknown tag type!"); 2777 case DeclSpec::TST_struct: Kind = TagDecl::TK_struct; break; 2778 case DeclSpec::TST_union: Kind = TagDecl::TK_union; break; 2779 case DeclSpec::TST_class: Kind = TagDecl::TK_class; break; 2780 case DeclSpec::TST_enum: Kind = TagDecl::TK_enum; break; 2781 } 2782 2783 DeclContext *SearchDC = CurContext; 2784 DeclContext *DC = CurContext; 2785 DeclContext *LexicalContext = CurContext; 2786 Decl *PrevDecl = 0; 2787 2788 bool Invalid = false; 2789 2790 if (Name && SS.isNotEmpty()) { 2791 // We have a nested-name tag ('struct foo::bar'). 2792 2793 // Check for invalid 'foo::'. 2794 if (SS.isInvalid()) { 2795 Name = 0; 2796 goto CreateNewDecl; 2797 } 2798 2799 DC = static_cast<DeclContext*>(SS.getScopeRep()); 2800 // Look-up name inside 'foo::'. 2801 PrevDecl = dyn_cast_or_null<TagDecl>( 2802 LookupQualifiedName(DC, Name, LookupTagName).getAsDecl()); 2803 2804 // A tag 'foo::bar' must already exist. 2805 if (PrevDecl == 0) { 2806 Diag(NameLoc, diag::err_not_tag_in_scope) << Name << SS.getRange(); 2807 Name = 0; 2808 goto CreateNewDecl; 2809 } 2810 } else if (Name) { 2811 // If this is a named struct, check to see if there was a previous forward 2812 // declaration or definition. 2813 Decl *D = LookupName(S, Name, LookupTagName); 2814 PrevDecl = dyn_cast_or_null<NamedDecl>(D); 2815 2816 if (!getLangOptions().CPlusPlus && TK != TK_Reference) { 2817 // FIXME: This makes sure that we ignore the contexts associated 2818 // with C structs, unions, and enums when looking for a matching 2819 // tag declaration or definition. See the similar lookup tweak 2820 // in Sema::LookupName; is there a better way to deal with this? 2821 while (isa<RecordDecl>(SearchDC) || isa<EnumDecl>(SearchDC)) 2822 SearchDC = SearchDC->getParent(); 2823 } 2824 } 2825 2826 if (PrevDecl && PrevDecl->isTemplateParameter()) { 2827 // Maybe we will complain about the shadowed template parameter. 2828 DiagnoseTemplateParameterShadow(NameLoc, PrevDecl); 2829 // Just pretend that we didn't see the previous declaration. 2830 PrevDecl = 0; 2831 } 2832 2833 if (PrevDecl) { 2834 if (TagDecl *PrevTagDecl = dyn_cast<TagDecl>(PrevDecl)) { 2835 // If this is a use of a previous tag, or if the tag is already declared 2836 // in the same scope (so that the definition/declaration completes or 2837 // rementions the tag), reuse the decl. 2838 if (TK == TK_Reference || isDeclInScope(PrevDecl, SearchDC, S)) { 2839 // Make sure that this wasn't declared as an enum and now used as a 2840 // struct or something similar. 2841 if (PrevTagDecl->getTagKind() != Kind) { 2842 Diag(KWLoc, diag::err_use_with_wrong_tag) << Name; 2843 Diag(PrevDecl->getLocation(), diag::note_previous_use); 2844 // Recover by making this an anonymous redefinition. 2845 Name = 0; 2846 PrevDecl = 0; 2847 Invalid = true; 2848 } else { 2849 // If this is a use, just return the declaration we found. 2850 2851 // FIXME: In the future, return a variant or some other clue 2852 // for the consumer of this Decl to know it doesn't own it. 2853 // For our current ASTs this shouldn't be a problem, but will 2854 // need to be changed with DeclGroups. 2855 if (TK == TK_Reference) 2856 return PrevDecl; 2857 2858 // Diagnose attempts to redefine a tag. 2859 if (TK == TK_Definition) { 2860 if (TagDecl *Def = PrevTagDecl->getDefinition(Context)) { 2861 Diag(NameLoc, diag::err_redefinition) << Name; 2862 Diag(Def->getLocation(), diag::note_previous_definition); 2863 // If this is a redefinition, recover by making this 2864 // struct be anonymous, which will make any later 2865 // references get the previous definition. 2866 Name = 0; 2867 PrevDecl = 0; 2868 Invalid = true; 2869 } else { 2870 // If the type is currently being defined, complain 2871 // about a nested redefinition. 2872 TagType *Tag = cast<TagType>(Context.getTagDeclType(PrevTagDecl)); 2873 if (Tag->isBeingDefined()) { 2874 Diag(NameLoc, diag::err_nested_redefinition) << Name; 2875 Diag(PrevTagDecl->getLocation(), 2876 diag::note_previous_definition); 2877 Name = 0; 2878 PrevDecl = 0; 2879 Invalid = true; 2880 } 2881 } 2882 2883 // Okay, this is definition of a previously declared or referenced 2884 // tag PrevDecl. We're going to create a new Decl for it. 2885 } 2886 } 2887 // If we get here we have (another) forward declaration or we 2888 // have a definition. Just create a new decl. 2889 } else { 2890 // If we get here, this is a definition of a new tag type in a nested 2891 // scope, e.g. "struct foo; void bar() { struct foo; }", just create a 2892 // new decl/type. We set PrevDecl to NULL so that the entities 2893 // have distinct types. 2894 PrevDecl = 0; 2895 } 2896 // If we get here, we're going to create a new Decl. If PrevDecl 2897 // is non-NULL, it's a definition of the tag declared by 2898 // PrevDecl. If it's NULL, we have a new definition. 2899 } else { 2900 // PrevDecl is a namespace, template, or anything else 2901 // that lives in the IDNS_Tag identifier namespace. 2902 if (isDeclInScope(PrevDecl, SearchDC, S)) { 2903 // The tag name clashes with a namespace name, issue an error and 2904 // recover by making this tag be anonymous. 2905 Diag(NameLoc, diag::err_redefinition_different_kind) << Name; 2906 Diag(PrevDecl->getLocation(), diag::note_previous_definition); 2907 Name = 0; 2908 PrevDecl = 0; 2909 Invalid = true; 2910 } else { 2911 // The existing declaration isn't relevant to us; we're in a 2912 // new scope, so clear out the previous declaration. 2913 PrevDecl = 0; 2914 } 2915 } 2916 } else if (TK == TK_Reference && SS.isEmpty() && Name && 2917 (Kind != TagDecl::TK_enum)) { 2918 // C++ [basic.scope.pdecl]p5: 2919 // -- for an elaborated-type-specifier of the form 2920 // 2921 // class-key identifier 2922 // 2923 // if the elaborated-type-specifier is used in the 2924 // decl-specifier-seq or parameter-declaration-clause of a 2925 // function defined in namespace scope, the identifier is 2926 // declared as a class-name in the namespace that contains 2927 // the declaration; otherwise, except as a friend 2928 // declaration, the identifier is declared in the smallest 2929 // non-class, non-function-prototype scope that contains the 2930 // declaration. 2931 // 2932 // C99 6.7.2.3p8 has a similar (but not identical!) provision for 2933 // C structs and unions. 2934 2935 // Find the context where we'll be declaring the tag. 2936 // FIXME: We would like to maintain the current DeclContext as the 2937 // lexical context, 2938 while (DC->isRecord()) 2939 DC = DC->getParent(); 2940 LexicalContext = DC; 2941 2942 // Find the scope where we'll be declaring the tag. 2943 while (S->isClassScope() || 2944 (getLangOptions().CPlusPlus && S->isFunctionPrototypeScope()) || 2945 ((S->getFlags() & Scope::DeclScope) == 0) || 2946 (S->getEntity() && 2947 ((DeclContext *)S->getEntity())->isTransparentContext())) 2948 S = S->getParent(); 2949 } 2950 2951CreateNewDecl: 2952 2953 // If there is an identifier, use the location of the identifier as the 2954 // location of the decl, otherwise use the location of the struct/union 2955 // keyword. 2956 SourceLocation Loc = NameLoc.isValid() ? NameLoc : KWLoc; 2957 2958 // Otherwise, create a new declaration. If there is a previous 2959 // declaration of the same entity, the two will be linked via 2960 // PrevDecl. 2961 TagDecl *New; 2962 2963 if (Kind == TagDecl::TK_enum) { 2964 // FIXME: Tag decls should be chained to any simultaneous vardecls, e.g.: 2965 // enum X { A, B, C } D; D should chain to X. 2966 New = EnumDecl::Create(Context, DC, Loc, Name, 2967 cast_or_null<EnumDecl>(PrevDecl)); 2968 // If this is an undefined enum, warn. 2969 if (TK != TK_Definition) Diag(Loc, diag::ext_forward_ref_enum); 2970 } else { 2971 // struct/union/class 2972 2973 // FIXME: Tag decls should be chained to any simultaneous vardecls, e.g.: 2974 // struct X { int A; } D; D should chain to X. 2975 if (getLangOptions().CPlusPlus) 2976 // FIXME: Look for a way to use RecordDecl for simple structs. 2977 New = CXXRecordDecl::Create(Context, Kind, DC, Loc, Name, 2978 cast_or_null<CXXRecordDecl>(PrevDecl)); 2979 else 2980 New = RecordDecl::Create(Context, Kind, DC, Loc, Name, 2981 cast_or_null<RecordDecl>(PrevDecl)); 2982 } 2983 2984 if (Kind != TagDecl::TK_enum) { 2985 // Handle #pragma pack: if the #pragma pack stack has non-default 2986 // alignment, make up a packed attribute for this decl. These 2987 // attributes are checked when the ASTContext lays out the 2988 // structure. 2989 // 2990 // It is important for implementing the correct semantics that this 2991 // happen here (in act on tag decl). The #pragma pack stack is 2992 // maintained as a result of parser callbacks which can occur at 2993 // many points during the parsing of a struct declaration (because 2994 // the #pragma tokens are effectively skipped over during the 2995 // parsing of the struct). 2996 if (unsigned Alignment = PackContext.getAlignment()) 2997 New->addAttr(new PackedAttr(Alignment * 8)); 2998 } 2999 3000 if (getLangOptions().CPlusPlus && SS.isEmpty() && Name && !Invalid) { 3001 // C++ [dcl.typedef]p3: 3002 // [...] Similarly, in a given scope, a class or enumeration 3003 // shall not be declared with the same name as a typedef-name 3004 // that is declared in that scope and refers to a type other 3005 // than the class or enumeration itself. 3006 LookupResult Lookup = LookupName(S, Name, LookupOrdinaryName, true); 3007 TypedefDecl *PrevTypedef = 0; 3008 if (Lookup.getKind() == LookupResult::Found) 3009 PrevTypedef = dyn_cast<TypedefDecl>(Lookup.getAsDecl()); 3010 3011 if (PrevTypedef && isDeclInScope(PrevTypedef, SearchDC, S) && 3012 Context.getCanonicalType(Context.getTypeDeclType(PrevTypedef)) != 3013 Context.getCanonicalType(Context.getTypeDeclType(New))) { 3014 Diag(Loc, diag::err_tag_definition_of_typedef) 3015 << Context.getTypeDeclType(New) 3016 << PrevTypedef->getUnderlyingType(); 3017 Diag(PrevTypedef->getLocation(), diag::note_previous_definition); 3018 Invalid = true; 3019 } 3020 } 3021 3022 if (Invalid) 3023 New->setInvalidDecl(); 3024 3025 if (Attr) 3026 ProcessDeclAttributeList(New, Attr); 3027 3028 // If we're declaring or defining a tag in function prototype scope 3029 // in C, note that this type can only be used within the function. 3030 if (Name && S->isFunctionPrototypeScope() && !getLangOptions().CPlusPlus) 3031 Diag(Loc, diag::warn_decl_in_param_list) << Context.getTagDeclType(New); 3032 3033 // Set the lexical context. If the tag has a C++ scope specifier, the 3034 // lexical context will be different from the semantic context. 3035 New->setLexicalDeclContext(LexicalContext); 3036 3037 if (TK == TK_Definition) 3038 New->startDefinition(); 3039 3040 // If this has an identifier, add it to the scope stack. 3041 if (Name) { 3042 S = getNonFieldDeclScope(S); 3043 3044 // Add it to the decl chain. 3045 if (LexicalContext != CurContext) { 3046 // FIXME: PushOnScopeChains should not rely on CurContext! 3047 DeclContext *OldContext = CurContext; 3048 CurContext = LexicalContext; 3049 PushOnScopeChains(New, S); 3050 CurContext = OldContext; 3051 } else 3052 PushOnScopeChains(New, S); 3053 } else { 3054 LexicalContext->addDecl(New); 3055 } 3056 3057 return New; 3058} 3059 3060void Sema::ActOnTagStartDefinition(Scope *S, DeclTy *TagD) { 3061 TagDecl *Tag = cast<TagDecl>((Decl *)TagD); 3062 3063 // Enter the tag context. 3064 PushDeclContext(S, Tag); 3065 3066 if (CXXRecordDecl *Record = dyn_cast<CXXRecordDecl>(Tag)) { 3067 FieldCollector->StartClass(); 3068 3069 if (Record->getIdentifier()) { 3070 // C++ [class]p2: 3071 // [...] The class-name is also inserted into the scope of the 3072 // class itself; this is known as the injected-class-name. For 3073 // purposes of access checking, the injected-class-name is treated 3074 // as if it were a public member name. 3075 RecordDecl *InjectedClassName 3076 = CXXRecordDecl::Create(Context, Record->getTagKind(), 3077 CurContext, Record->getLocation(), 3078 Record->getIdentifier(), Record); 3079 InjectedClassName->setImplicit(); 3080 PushOnScopeChains(InjectedClassName, S); 3081 } 3082 } 3083} 3084 3085void Sema::ActOnTagFinishDefinition(Scope *S, DeclTy *TagD) { 3086 TagDecl *Tag = cast<TagDecl>((Decl *)TagD); 3087 3088 if (isa<CXXRecordDecl>(Tag)) 3089 FieldCollector->FinishClass(); 3090 3091 // Exit this scope of this tag's definition. 3092 PopDeclContext(); 3093 3094 // Notify the consumer that we've defined a tag. 3095 Consumer.HandleTagDeclDefinition(Tag); 3096} 3097 3098/// TryToFixInvalidVariablyModifiedType - Helper method to turn variable array 3099/// types into constant array types in certain situations which would otherwise 3100/// be errors (for GCC compatibility). 3101static QualType TryToFixInvalidVariablyModifiedType(QualType T, 3102 ASTContext &Context) { 3103 // This method tries to turn a variable array into a constant 3104 // array even when the size isn't an ICE. This is necessary 3105 // for compatibility with code that depends on gcc's buggy 3106 // constant expression folding, like struct {char x[(int)(char*)2];} 3107 const VariableArrayType* VLATy = dyn_cast<VariableArrayType>(T); 3108 if (!VLATy) return QualType(); 3109 3110 Expr::EvalResult EvalResult; 3111 if (!VLATy->getSizeExpr() || 3112 !VLATy->getSizeExpr()->Evaluate(EvalResult, Context)) 3113 return QualType(); 3114 3115 assert(EvalResult.Val.isInt() && "Size expressions must be integers!"); 3116 llvm::APSInt &Res = EvalResult.Val.getInt(); 3117 if (Res >= llvm::APSInt(Res.getBitWidth(), Res.isUnsigned())) 3118 return Context.getConstantArrayType(VLATy->getElementType(), 3119 Res, ArrayType::Normal, 0); 3120 return QualType(); 3121} 3122 3123bool Sema::VerifyBitField(SourceLocation FieldLoc, IdentifierInfo *FieldName, 3124 QualType FieldTy, const Expr *BitWidth) { 3125 // FIXME: 6.7.2.1p4 - verify the field type. 3126 3127 llvm::APSInt Value; 3128 if (VerifyIntegerConstantExpression(BitWidth, &Value)) 3129 return true; 3130 3131 // Zero-width bitfield is ok for anonymous field. 3132 if (Value == 0 && FieldName) 3133 return Diag(FieldLoc, diag::err_bitfield_has_zero_width) << FieldName; 3134 3135 if (Value.isNegative()) 3136 return Diag(FieldLoc, diag::err_bitfield_has_negative_width) << FieldName; 3137 3138 uint64_t TypeSize = Context.getTypeSize(FieldTy); 3139 // FIXME: We won't need the 0 size once we check that the field type is valid. 3140 if (TypeSize && Value.getZExtValue() > TypeSize) 3141 return Diag(FieldLoc, diag::err_bitfield_width_exceeds_type_size) 3142 << FieldName << (unsigned)TypeSize; 3143 3144 return false; 3145} 3146 3147/// ActOnField - Each field of a struct/union/class is passed into this in order 3148/// to create a FieldDecl object for it. 3149Sema::DeclTy *Sema::ActOnField(Scope *S, DeclTy *TagD, 3150 SourceLocation DeclStart, 3151 Declarator &D, ExprTy *BitfieldWidth) { 3152 IdentifierInfo *II = D.getIdentifier(); 3153 Expr *BitWidth = (Expr*)BitfieldWidth; 3154 SourceLocation Loc = DeclStart; 3155 RecordDecl *Record = (RecordDecl *)TagD; 3156 if (II) Loc = D.getIdentifierLoc(); 3157 3158 // FIXME: Unnamed fields can be handled in various different ways, for 3159 // example, unnamed unions inject all members into the struct namespace! 3160 3161 QualType T = GetTypeForDeclarator(D, S); 3162 assert(!T.isNull() && "GetTypeForDeclarator() returned null type"); 3163 bool InvalidDecl = false; 3164 3165 // C99 6.7.2.1p8: A member of a structure or union may have any type other 3166 // than a variably modified type. 3167 if (T->isVariablyModifiedType()) { 3168 QualType FixedTy = TryToFixInvalidVariablyModifiedType(T, Context); 3169 if (!FixedTy.isNull()) { 3170 Diag(Loc, diag::warn_illegal_constant_array_size); 3171 T = FixedTy; 3172 } else { 3173 Diag(Loc, diag::err_typecheck_field_variable_size); 3174 T = Context.IntTy; 3175 InvalidDecl = true; 3176 } 3177 } 3178 3179 if (BitWidth) { 3180 if (VerifyBitField(Loc, II, T, BitWidth)) 3181 InvalidDecl = true; 3182 } else { 3183 // Not a bitfield. 3184 3185 // validate II. 3186 3187 } 3188 3189 // FIXME: Chain fielddecls together. 3190 FieldDecl *NewFD; 3191 3192 NewFD = FieldDecl::Create(Context, Record, 3193 Loc, II, T, BitWidth, 3194 D.getDeclSpec().getStorageClassSpec() == 3195 DeclSpec::SCS_mutable); 3196 3197 if (II) { 3198 Decl *PrevDecl = LookupName(S, II, LookupMemberName, true); 3199 if (PrevDecl && isDeclInScope(PrevDecl, CurContext, S) 3200 && !isa<TagDecl>(PrevDecl)) { 3201 Diag(Loc, diag::err_duplicate_member) << II; 3202 Diag(PrevDecl->getLocation(), diag::note_previous_declaration); 3203 NewFD->setInvalidDecl(); 3204 Record->setInvalidDecl(); 3205 } 3206 } 3207 3208 if (getLangOptions().CPlusPlus) { 3209 CheckExtraCXXDefaultArguments(D); 3210 if (!T->isPODType()) 3211 cast<CXXRecordDecl>(Record)->setPOD(false); 3212 } 3213 3214 ProcessDeclAttributes(NewFD, D); 3215 3216 if (D.getInvalidType() || InvalidDecl) 3217 NewFD->setInvalidDecl(); 3218 3219 if (II) { 3220 PushOnScopeChains(NewFD, S); 3221 } else 3222 Record->addDecl(NewFD); 3223 3224 return NewFD; 3225} 3226 3227/// TranslateIvarVisibility - Translate visibility from a token ID to an 3228/// AST enum value. 3229static ObjCIvarDecl::AccessControl 3230TranslateIvarVisibility(tok::ObjCKeywordKind ivarVisibility) { 3231 switch (ivarVisibility) { 3232 default: assert(0 && "Unknown visitibility kind"); 3233 case tok::objc_private: return ObjCIvarDecl::Private; 3234 case tok::objc_public: return ObjCIvarDecl::Public; 3235 case tok::objc_protected: return ObjCIvarDecl::Protected; 3236 case tok::objc_package: return ObjCIvarDecl::Package; 3237 } 3238} 3239 3240/// ActOnIvar - Each ivar field of an objective-c class is passed into this 3241/// in order to create an IvarDecl object for it. 3242Sema::DeclTy *Sema::ActOnIvar(Scope *S, 3243 SourceLocation DeclStart, 3244 Declarator &D, ExprTy *BitfieldWidth, 3245 tok::ObjCKeywordKind Visibility) { 3246 3247 IdentifierInfo *II = D.getIdentifier(); 3248 Expr *BitWidth = (Expr*)BitfieldWidth; 3249 SourceLocation Loc = DeclStart; 3250 if (II) Loc = D.getIdentifierLoc(); 3251 3252 // FIXME: Unnamed fields can be handled in various different ways, for 3253 // example, unnamed unions inject all members into the struct namespace! 3254 3255 QualType T = GetTypeForDeclarator(D, S); 3256 assert(!T.isNull() && "GetTypeForDeclarator() returned null type"); 3257 bool InvalidDecl = false; 3258 3259 if (BitWidth) { 3260 // TODO: Validate. 3261 //printf("WARNING: BITFIELDS IGNORED!\n"); 3262 3263 // 6.7.2.1p3 3264 // 6.7.2.1p4 3265 3266 } else { 3267 // Not a bitfield. 3268 3269 // validate II. 3270 3271 } 3272 3273 // C99 6.7.2.1p8: A member of a structure or union may have any type other 3274 // than a variably modified type. 3275 if (T->isVariablyModifiedType()) { 3276 Diag(Loc, diag::err_typecheck_ivar_variable_size); 3277 InvalidDecl = true; 3278 } 3279 3280 // Get the visibility (access control) for this ivar. 3281 ObjCIvarDecl::AccessControl ac = 3282 Visibility != tok::objc_not_keyword ? TranslateIvarVisibility(Visibility) 3283 : ObjCIvarDecl::None; 3284 3285 // Construct the decl. 3286 ObjCIvarDecl *NewID = ObjCIvarDecl::Create(Context, Loc, II, T, ac, 3287 (Expr *)BitfieldWidth); 3288 3289 if (II) { 3290 Decl *PrevDecl = LookupName(S, II, LookupMemberName, true); 3291 if (PrevDecl && isDeclInScope(PrevDecl, CurContext, S) 3292 && !isa<TagDecl>(PrevDecl)) { 3293 Diag(Loc, diag::err_duplicate_member) << II; 3294 Diag(PrevDecl->getLocation(), diag::note_previous_declaration); 3295 NewID->setInvalidDecl(); 3296 } 3297 } 3298 3299 // Process attributes attached to the ivar. 3300 ProcessDeclAttributes(NewID, D); 3301 3302 if (D.getInvalidType() || InvalidDecl) 3303 NewID->setInvalidDecl(); 3304 3305 if (II) { 3306 // FIXME: When interfaces are DeclContexts, we'll need to add 3307 // these to the interface. 3308 S->AddDecl(NewID); 3309 IdResolver.AddDecl(NewID); 3310 } 3311 3312 return NewID; 3313} 3314 3315void Sema::ActOnFields(Scope* S, 3316 SourceLocation RecLoc, DeclTy *RecDecl, 3317 DeclTy **Fields, unsigned NumFields, 3318 SourceLocation LBrac, SourceLocation RBrac, 3319 AttributeList *Attr) { 3320 Decl *EnclosingDecl = static_cast<Decl*>(RecDecl); 3321 assert(EnclosingDecl && "missing record or interface decl"); 3322 RecordDecl *Record = dyn_cast<RecordDecl>(EnclosingDecl); 3323 3324 // Verify that all the fields are okay. 3325 unsigned NumNamedMembers = 0; 3326 llvm::SmallVector<FieldDecl*, 32> RecFields; 3327 3328 for (unsigned i = 0; i != NumFields; ++i) { 3329 FieldDecl *FD = cast_or_null<FieldDecl>(static_cast<Decl*>(Fields[i])); 3330 assert(FD && "missing field decl"); 3331 3332 // Get the type for the field. 3333 Type *FDTy = FD->getType().getTypePtr(); 3334 3335 if (!FD->isAnonymousStructOrUnion()) { 3336 // Remember all fields written by the user. 3337 RecFields.push_back(FD); 3338 } 3339 3340 // C99 6.7.2.1p2 - A field may not be a function type. 3341 if (FDTy->isFunctionType()) { 3342 Diag(FD->getLocation(), diag::err_field_declared_as_function) 3343 << FD->getDeclName(); 3344 FD->setInvalidDecl(); 3345 EnclosingDecl->setInvalidDecl(); 3346 continue; 3347 } 3348 // C99 6.7.2.1p2 - A field may not be an incomplete type except... 3349 if (FDTy->isIncompleteType()) { 3350 if (!Record) { // Incomplete ivar type is always an error. 3351 DiagnoseIncompleteType(FD->getLocation(), FD->getType(), 3352 diag::err_field_incomplete); 3353 FD->setInvalidDecl(); 3354 EnclosingDecl->setInvalidDecl(); 3355 continue; 3356 } 3357 if (i != NumFields-1 || // ... that the last member ... 3358 !Record->isStruct() || // ... of a structure ... 3359 !FDTy->isArrayType()) { //... may have incomplete array type. 3360 DiagnoseIncompleteType(FD->getLocation(), FD->getType(), 3361 diag::err_field_incomplete); 3362 FD->setInvalidDecl(); 3363 EnclosingDecl->setInvalidDecl(); 3364 continue; 3365 } 3366 if (NumNamedMembers < 1) { //... must have more than named member ... 3367 Diag(FD->getLocation(), diag::err_flexible_array_empty_struct) 3368 << FD->getDeclName(); 3369 FD->setInvalidDecl(); 3370 EnclosingDecl->setInvalidDecl(); 3371 continue; 3372 } 3373 // Okay, we have a legal flexible array member at the end of the struct. 3374 if (Record) 3375 Record->setHasFlexibleArrayMember(true); 3376 } 3377 /// C99 6.7.2.1p2 - a struct ending in a flexible array member cannot be the 3378 /// field of another structure or the element of an array. 3379 if (const RecordType *FDTTy = FDTy->getAsRecordType()) { 3380 if (FDTTy->getDecl()->hasFlexibleArrayMember()) { 3381 // If this is a member of a union, then entire union becomes "flexible". 3382 if (Record && Record->isUnion()) { 3383 Record->setHasFlexibleArrayMember(true); 3384 } else { 3385 // If this is a struct/class and this is not the last element, reject 3386 // it. Note that GCC supports variable sized arrays in the middle of 3387 // structures. 3388 if (i != NumFields-1) { 3389 Diag(FD->getLocation(), diag::err_variable_sized_type_in_struct) 3390 << FD->getDeclName(); 3391 FD->setInvalidDecl(); 3392 EnclosingDecl->setInvalidDecl(); 3393 continue; 3394 } 3395 // We support flexible arrays at the end of structs in other structs 3396 // as an extension. 3397 Diag(FD->getLocation(), diag::ext_flexible_array_in_struct) 3398 << FD->getDeclName(); 3399 if (Record) 3400 Record->setHasFlexibleArrayMember(true); 3401 } 3402 } 3403 } 3404 /// A field cannot be an Objective-c object 3405 if (FDTy->isObjCInterfaceType()) { 3406 Diag(FD->getLocation(), diag::err_statically_allocated_object) 3407 << FD->getDeclName(); 3408 FD->setInvalidDecl(); 3409 EnclosingDecl->setInvalidDecl(); 3410 continue; 3411 } 3412 // Keep track of the number of named members. 3413 if (FD->getIdentifier()) 3414 ++NumNamedMembers; 3415 } 3416 3417 // Okay, we successfully defined 'Record'. 3418 if (Record) { 3419 Record->completeDefinition(Context); 3420 } else { 3421 ObjCIvarDecl **ClsFields = reinterpret_cast<ObjCIvarDecl**>(&RecFields[0]); 3422 if (ObjCInterfaceDecl *ID = dyn_cast<ObjCInterfaceDecl>(EnclosingDecl)) { 3423 ID->addInstanceVariablesToClass(ClsFields, RecFields.size(), RBrac); 3424 // Must enforce the rule that ivars in the base classes may not be 3425 // duplicates. 3426 if (ID->getSuperClass()) { 3427 for (ObjCInterfaceDecl::ivar_iterator IVI = ID->ivar_begin(), 3428 IVE = ID->ivar_end(); IVI != IVE; ++IVI) { 3429 ObjCIvarDecl* Ivar = (*IVI); 3430 IdentifierInfo *II = Ivar->getIdentifier(); 3431 ObjCIvarDecl* prevIvar = ID->getSuperClass()->FindIvarDeclaration(II); 3432 if (prevIvar) { 3433 Diag(Ivar->getLocation(), diag::err_duplicate_member) << II; 3434 Diag(prevIvar->getLocation(), diag::note_previous_declaration); 3435 } 3436 } 3437 } 3438 } 3439 else if (ObjCImplementationDecl *IMPDecl = 3440 dyn_cast<ObjCImplementationDecl>(EnclosingDecl)) { 3441 assert(IMPDecl && "ActOnFields - missing ObjCImplementationDecl"); 3442 IMPDecl->ObjCAddInstanceVariablesToClassImpl(ClsFields, RecFields.size()); 3443 CheckImplementationIvars(IMPDecl, ClsFields, RecFields.size(), RBrac); 3444 } 3445 } 3446 3447 if (Attr) 3448 ProcessDeclAttributeList(Record, Attr); 3449} 3450 3451Sema::DeclTy *Sema::ActOnEnumConstant(Scope *S, DeclTy *theEnumDecl, 3452 DeclTy *lastEnumConst, 3453 SourceLocation IdLoc, IdentifierInfo *Id, 3454 SourceLocation EqualLoc, ExprTy *val) { 3455 EnumDecl *TheEnumDecl = cast<EnumDecl>(static_cast<Decl*>(theEnumDecl)); 3456 EnumConstantDecl *LastEnumConst = 3457 cast_or_null<EnumConstantDecl>(static_cast<Decl*>(lastEnumConst)); 3458 Expr *Val = static_cast<Expr*>(val); 3459 3460 // The scope passed in may not be a decl scope. Zip up the scope tree until 3461 // we find one that is. 3462 S = getNonFieldDeclScope(S); 3463 3464 // Verify that there isn't already something declared with this name in this 3465 // scope. 3466 Decl *PrevDecl = LookupName(S, Id, LookupOrdinaryName); 3467 if (PrevDecl && PrevDecl->isTemplateParameter()) { 3468 // Maybe we will complain about the shadowed template parameter. 3469 DiagnoseTemplateParameterShadow(IdLoc, PrevDecl); 3470 // Just pretend that we didn't see the previous declaration. 3471 PrevDecl = 0; 3472 } 3473 3474 if (PrevDecl) { 3475 // When in C++, we may get a TagDecl with the same name; in this case the 3476 // enum constant will 'hide' the tag. 3477 assert((getLangOptions().CPlusPlus || !isa<TagDecl>(PrevDecl)) && 3478 "Received TagDecl when not in C++!"); 3479 if (!isa<TagDecl>(PrevDecl) && isDeclInScope(PrevDecl, CurContext, S)) { 3480 if (isa<EnumConstantDecl>(PrevDecl)) 3481 Diag(IdLoc, diag::err_redefinition_of_enumerator) << Id; 3482 else 3483 Diag(IdLoc, diag::err_redefinition) << Id; 3484 Diag(PrevDecl->getLocation(), diag::note_previous_definition); 3485 delete Val; 3486 return 0; 3487 } 3488 } 3489 3490 llvm::APSInt EnumVal(32); 3491 QualType EltTy; 3492 if (Val) { 3493 // Make sure to promote the operand type to int. 3494 UsualUnaryConversions(Val); 3495 3496 // C99 6.7.2.2p2: Make sure we have an integer constant expression. 3497 SourceLocation ExpLoc; 3498 if (VerifyIntegerConstantExpression(Val, &EnumVal)) { 3499 delete Val; 3500 Val = 0; // Just forget about it. 3501 } else { 3502 EltTy = Val->getType(); 3503 } 3504 } 3505 3506 if (!Val) { 3507 if (LastEnumConst) { 3508 // Assign the last value + 1. 3509 EnumVal = LastEnumConst->getInitVal(); 3510 ++EnumVal; 3511 3512 // Check for overflow on increment. 3513 if (EnumVal < LastEnumConst->getInitVal()) 3514 Diag(IdLoc, diag::warn_enum_value_overflow); 3515 3516 EltTy = LastEnumConst->getType(); 3517 } else { 3518 // First value, set to zero. 3519 EltTy = Context.IntTy; 3520 EnumVal.zextOrTrunc(static_cast<uint32_t>(Context.getTypeSize(EltTy))); 3521 } 3522 } 3523 3524 EnumConstantDecl *New = 3525 EnumConstantDecl::Create(Context, TheEnumDecl, IdLoc, Id, EltTy, 3526 Val, EnumVal); 3527 3528 // Register this decl in the current scope stack. 3529 PushOnScopeChains(New, S); 3530 3531 return New; 3532} 3533 3534// FIXME: For consistency with ActOnFields(), we should have the parser 3535// pass in the source location for the left/right braces. 3536void Sema::ActOnEnumBody(SourceLocation EnumLoc, DeclTy *EnumDeclX, 3537 DeclTy **Elements, unsigned NumElements) { 3538 EnumDecl *Enum = cast<EnumDecl>(static_cast<Decl*>(EnumDeclX)); 3539 QualType EnumType = Context.getTypeDeclType(Enum); 3540 3541 // TODO: If the result value doesn't fit in an int, it must be a long or long 3542 // long value. ISO C does not support this, but GCC does as an extension, 3543 // emit a warning. 3544 unsigned IntWidth = Context.Target.getIntWidth(); 3545 3546 // Verify that all the values are okay, compute the size of the values, and 3547 // reverse the list. 3548 unsigned NumNegativeBits = 0; 3549 unsigned NumPositiveBits = 0; 3550 3551 // Keep track of whether all elements have type int. 3552 bool AllElementsInt = true; 3553 3554 for (unsigned i = 0; i != NumElements; ++i) { 3555 EnumConstantDecl *ECD = 3556 cast_or_null<EnumConstantDecl>(static_cast<Decl*>(Elements[i])); 3557 if (!ECD) continue; // Already issued a diagnostic. 3558 3559 // If the enum value doesn't fit in an int, emit an extension warning. 3560 const llvm::APSInt &InitVal = ECD->getInitVal(); 3561 assert(InitVal.getBitWidth() >= IntWidth && 3562 "Should have promoted value to int"); 3563 if (InitVal.getBitWidth() > IntWidth) { 3564 llvm::APSInt V(InitVal); 3565 V.trunc(IntWidth); 3566 V.extend(InitVal.getBitWidth()); 3567 if (V != InitVal) 3568 Diag(ECD->getLocation(), diag::ext_enum_value_not_int) 3569 << InitVal.toString(10); 3570 } 3571 3572 // Keep track of the size of positive and negative values. 3573 if (InitVal.isUnsigned() || InitVal.isNonNegative()) 3574 NumPositiveBits = std::max(NumPositiveBits, 3575 (unsigned)InitVal.getActiveBits()); 3576 else 3577 NumNegativeBits = std::max(NumNegativeBits, 3578 (unsigned)InitVal.getMinSignedBits()); 3579 3580 // Keep track of whether every enum element has type int (very commmon). 3581 if (AllElementsInt) 3582 AllElementsInt = ECD->getType() == Context.IntTy; 3583 } 3584 3585 // Figure out the type that should be used for this enum. 3586 // FIXME: Support attribute(packed) on enums and -fshort-enums. 3587 QualType BestType; 3588 unsigned BestWidth; 3589 3590 if (NumNegativeBits) { 3591 // If there is a negative value, figure out the smallest integer type (of 3592 // int/long/longlong) that fits. 3593 if (NumNegativeBits <= IntWidth && NumPositiveBits < IntWidth) { 3594 BestType = Context.IntTy; 3595 BestWidth = IntWidth; 3596 } else { 3597 BestWidth = Context.Target.getLongWidth(); 3598 3599 if (NumNegativeBits <= BestWidth && NumPositiveBits < BestWidth) 3600 BestType = Context.LongTy; 3601 else { 3602 BestWidth = Context.Target.getLongLongWidth(); 3603 3604 if (NumNegativeBits > BestWidth || NumPositiveBits >= BestWidth) 3605 Diag(Enum->getLocation(), diag::warn_enum_too_large); 3606 BestType = Context.LongLongTy; 3607 } 3608 } 3609 } else { 3610 // If there is no negative value, figure out which of uint, ulong, ulonglong 3611 // fits. 3612 if (NumPositiveBits <= IntWidth) { 3613 BestType = Context.UnsignedIntTy; 3614 BestWidth = IntWidth; 3615 } else if (NumPositiveBits <= 3616 (BestWidth = Context.Target.getLongWidth())) { 3617 BestType = Context.UnsignedLongTy; 3618 } else { 3619 BestWidth = Context.Target.getLongLongWidth(); 3620 assert(NumPositiveBits <= BestWidth && 3621 "How could an initializer get larger than ULL?"); 3622 BestType = Context.UnsignedLongLongTy; 3623 } 3624 } 3625 3626 // Loop over all of the enumerator constants, changing their types to match 3627 // the type of the enum if needed. 3628 for (unsigned i = 0; i != NumElements; ++i) { 3629 EnumConstantDecl *ECD = 3630 cast_or_null<EnumConstantDecl>(static_cast<Decl*>(Elements[i])); 3631 if (!ECD) continue; // Already issued a diagnostic. 3632 3633 // Standard C says the enumerators have int type, but we allow, as an 3634 // extension, the enumerators to be larger than int size. If each 3635 // enumerator value fits in an int, type it as an int, otherwise type it the 3636 // same as the enumerator decl itself. This means that in "enum { X = 1U }" 3637 // that X has type 'int', not 'unsigned'. 3638 if (ECD->getType() == Context.IntTy) { 3639 // Make sure the init value is signed. 3640 llvm::APSInt IV = ECD->getInitVal(); 3641 IV.setIsSigned(true); 3642 ECD->setInitVal(IV); 3643 3644 if (getLangOptions().CPlusPlus) 3645 // C++ [dcl.enum]p4: Following the closing brace of an 3646 // enum-specifier, each enumerator has the type of its 3647 // enumeration. 3648 ECD->setType(EnumType); 3649 continue; // Already int type. 3650 } 3651 3652 // Determine whether the value fits into an int. 3653 llvm::APSInt InitVal = ECD->getInitVal(); 3654 bool FitsInInt; 3655 if (InitVal.isUnsigned() || !InitVal.isNegative()) 3656 FitsInInt = InitVal.getActiveBits() < IntWidth; 3657 else 3658 FitsInInt = InitVal.getMinSignedBits() <= IntWidth; 3659 3660 // If it fits into an integer type, force it. Otherwise force it to match 3661 // the enum decl type. 3662 QualType NewTy; 3663 unsigned NewWidth; 3664 bool NewSign; 3665 if (FitsInInt) { 3666 NewTy = Context.IntTy; 3667 NewWidth = IntWidth; 3668 NewSign = true; 3669 } else if (ECD->getType() == BestType) { 3670 // Already the right type! 3671 if (getLangOptions().CPlusPlus) 3672 // C++ [dcl.enum]p4: Following the closing brace of an 3673 // enum-specifier, each enumerator has the type of its 3674 // enumeration. 3675 ECD->setType(EnumType); 3676 continue; 3677 } else { 3678 NewTy = BestType; 3679 NewWidth = BestWidth; 3680 NewSign = BestType->isSignedIntegerType(); 3681 } 3682 3683 // Adjust the APSInt value. 3684 InitVal.extOrTrunc(NewWidth); 3685 InitVal.setIsSigned(NewSign); 3686 ECD->setInitVal(InitVal); 3687 3688 // Adjust the Expr initializer and type. 3689 if (ECD->getInitExpr()) 3690 ECD->setInitExpr(new ImplicitCastExpr(NewTy, ECD->getInitExpr(), 3691 /*isLvalue=*/false)); 3692 if (getLangOptions().CPlusPlus) 3693 // C++ [dcl.enum]p4: Following the closing brace of an 3694 // enum-specifier, each enumerator has the type of its 3695 // enumeration. 3696 ECD->setType(EnumType); 3697 else 3698 ECD->setType(NewTy); 3699 } 3700 3701 Enum->completeDefinition(Context, BestType); 3702} 3703 3704Sema::DeclTy *Sema::ActOnFileScopeAsmDecl(SourceLocation Loc, 3705 ExprArg expr) { 3706 StringLiteral *AsmString = cast<StringLiteral>((Expr*)expr.release()); 3707 3708 return FileScopeAsmDecl::Create(Context, CurContext, Loc, AsmString); 3709} 3710 3711 3712void Sema::ActOnPragmaPack(PragmaPackKind Kind, IdentifierInfo *Name, 3713 ExprTy *alignment, SourceLocation PragmaLoc, 3714 SourceLocation LParenLoc, SourceLocation RParenLoc) { 3715 Expr *Alignment = static_cast<Expr *>(alignment); 3716 3717 // If specified then alignment must be a "small" power of two. 3718 unsigned AlignmentVal = 0; 3719 if (Alignment) { 3720 llvm::APSInt Val; 3721 if (!Alignment->isIntegerConstantExpr(Val, Context) || 3722 !Val.isPowerOf2() || 3723 Val.getZExtValue() > 16) { 3724 Diag(PragmaLoc, diag::warn_pragma_pack_invalid_alignment); 3725 delete Alignment; 3726 return; // Ignore 3727 } 3728 3729 AlignmentVal = (unsigned) Val.getZExtValue(); 3730 } 3731 3732 switch (Kind) { 3733 case Action::PPK_Default: // pack([n]) 3734 PackContext.setAlignment(AlignmentVal); 3735 break; 3736 3737 case Action::PPK_Show: // pack(show) 3738 // Show the current alignment, making sure to show the right value 3739 // for the default. 3740 AlignmentVal = PackContext.getAlignment(); 3741 // FIXME: This should come from the target. 3742 if (AlignmentVal == 0) 3743 AlignmentVal = 8; 3744 Diag(PragmaLoc, diag::warn_pragma_pack_show) << AlignmentVal; 3745 break; 3746 3747 case Action::PPK_Push: // pack(push [, id] [, [n]) 3748 PackContext.push(Name); 3749 // Set the new alignment if specified. 3750 if (Alignment) 3751 PackContext.setAlignment(AlignmentVal); 3752 break; 3753 3754 case Action::PPK_Pop: // pack(pop [, id] [, n]) 3755 // MSDN, C/C++ Preprocessor Reference > Pragma Directives > pack: 3756 // "#pragma pack(pop, identifier, n) is undefined" 3757 if (Alignment && Name) 3758 Diag(PragmaLoc, diag::warn_pragma_pack_pop_identifer_and_alignment); 3759 3760 // Do the pop. 3761 if (!PackContext.pop(Name)) { 3762 // If a name was specified then failure indicates the name 3763 // wasn't found. Otherwise failure indicates the stack was 3764 // empty. 3765 Diag(PragmaLoc, diag::warn_pragma_pack_pop_failed) 3766 << (Name ? "no record matching name" : "stack empty"); 3767 3768 // FIXME: Warn about popping named records as MSVC does. 3769 } else { 3770 // Pop succeeded, set the new alignment if specified. 3771 if (Alignment) 3772 PackContext.setAlignment(AlignmentVal); 3773 } 3774 break; 3775 3776 default: 3777 assert(0 && "Invalid #pragma pack kind."); 3778 } 3779} 3780 3781bool PragmaPackStack::pop(IdentifierInfo *Name) { 3782 if (Stack.empty()) 3783 return false; 3784 3785 // If name is empty just pop top. 3786 if (!Name) { 3787 Alignment = Stack.back().first; 3788 Stack.pop_back(); 3789 return true; 3790 } 3791 3792 // Otherwise, find the named record. 3793 for (unsigned i = Stack.size(); i != 0; ) { 3794 --i; 3795 if (Stack[i].second == Name) { 3796 // Found it, pop up to and including this record. 3797 Alignment = Stack[i].first; 3798 Stack.erase(Stack.begin() + i, Stack.end()); 3799 return true; 3800 } 3801 } 3802 3803 return false; 3804} 3805