SemaDecl.cpp revision 1931b44da8da86979a8d7ceb48685686503f197b
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 (isa<TagDecl>(*Mem) && (*Mem)->getDeclContext() != Record) { 843 // This is a type that showed up in an 844 // elaborated-type-specifier inside the anonymous struct or 845 // union, but which actually declares a type outside of the 846 // anonymous struct or union. It's okay. 847 } else if (RecordDecl *MemRecord = dyn_cast<RecordDecl>(*Mem)) { 848 if (!MemRecord->isAnonymousStructOrUnion() && 849 MemRecord->getDeclName()) { 850 // This is a nested type declaration. 851 Diag(MemRecord->getLocation(), diag::err_anonymous_record_with_type) 852 << (int)Record->isUnion(); 853 Invalid = true; 854 } 855 } else { 856 // We have something that isn't a non-static data 857 // member. Complain about it. 858 unsigned DK = diag::err_anonymous_record_bad_member; 859 if (isa<TypeDecl>(*Mem)) 860 DK = diag::err_anonymous_record_with_type; 861 else if (isa<FunctionDecl>(*Mem)) 862 DK = diag::err_anonymous_record_with_function; 863 else if (isa<VarDecl>(*Mem)) 864 DK = diag::err_anonymous_record_with_static; 865 Diag((*Mem)->getLocation(), DK) 866 << (int)Record->isUnion(); 867 Invalid = true; 868 } 869 } 870 } else { 871 // FIXME: Check GNU C semantics 872 if (Record->isUnion() && !Owner->isRecord()) { 873 Diag(Record->getLocation(), diag::err_anonymous_union_not_member) 874 << (int)getLangOptions().CPlusPlus; 875 Invalid = true; 876 } 877 } 878 879 if (!Record->isUnion() && !Owner->isRecord()) { 880 Diag(Record->getLocation(), diag::err_anonymous_struct_not_member) 881 << (int)getLangOptions().CPlusPlus; 882 Invalid = true; 883 } 884 885 // Create a declaration for this anonymous struct/union. 886 NamedDecl *Anon = 0; 887 if (RecordDecl *OwningClass = dyn_cast<RecordDecl>(Owner)) { 888 Anon = FieldDecl::Create(Context, OwningClass, Record->getLocation(), 889 /*IdentifierInfo=*/0, 890 Context.getTypeDeclType(Record), 891 /*BitWidth=*/0, /*Mutable=*/false); 892 Anon->setAccess(AS_public); 893 if (getLangOptions().CPlusPlus) 894 FieldCollector->Add(cast<FieldDecl>(Anon)); 895 } else { 896 VarDecl::StorageClass SC; 897 switch (DS.getStorageClassSpec()) { 898 default: assert(0 && "Unknown storage class!"); 899 case DeclSpec::SCS_unspecified: SC = VarDecl::None; break; 900 case DeclSpec::SCS_extern: SC = VarDecl::Extern; break; 901 case DeclSpec::SCS_static: SC = VarDecl::Static; break; 902 case DeclSpec::SCS_auto: SC = VarDecl::Auto; break; 903 case DeclSpec::SCS_register: SC = VarDecl::Register; break; 904 case DeclSpec::SCS_private_extern: SC = VarDecl::PrivateExtern; break; 905 case DeclSpec::SCS_mutable: 906 // mutable can only appear on non-static class members, so it's always 907 // an error here 908 Diag(Record->getLocation(), diag::err_mutable_nonmember); 909 Invalid = true; 910 SC = VarDecl::None; 911 break; 912 } 913 914 Anon = VarDecl::Create(Context, Owner, Record->getLocation(), 915 /*IdentifierInfo=*/0, 916 Context.getTypeDeclType(Record), 917 SC, DS.getSourceRange().getBegin()); 918 } 919 Anon->setImplicit(); 920 921 // Add the anonymous struct/union object to the current 922 // context. We'll be referencing this object when we refer to one of 923 // its members. 924 Owner->addDecl(Anon); 925 926 // Inject the members of the anonymous struct/union into the owning 927 // context and into the identifier resolver chain for name lookup 928 // purposes. 929 if (InjectAnonymousStructOrUnionMembers(S, Owner, Record)) 930 Invalid = true; 931 932 // Mark this as an anonymous struct/union type. Note that we do not 933 // do this until after we have already checked and injected the 934 // members of this anonymous struct/union type, because otherwise 935 // the members could be injected twice: once by DeclContext when it 936 // builds its lookup table, and once by 937 // InjectAnonymousStructOrUnionMembers. 938 Record->setAnonymousStructOrUnion(true); 939 940 if (Invalid) 941 Anon->setInvalidDecl(); 942 943 return Anon; 944} 945 946bool Sema::CheckSingleInitializer(Expr *&Init, QualType DeclType, 947 bool DirectInit) { 948 // Get the type before calling CheckSingleAssignmentConstraints(), since 949 // it can promote the expression. 950 QualType InitType = Init->getType(); 951 952 if (getLangOptions().CPlusPlus) { 953 // FIXME: I dislike this error message. A lot. 954 if (PerformImplicitConversion(Init, DeclType, "initializing", DirectInit)) 955 return Diag(Init->getSourceRange().getBegin(), 956 diag::err_typecheck_convert_incompatible) 957 << DeclType << Init->getType() << "initializing" 958 << Init->getSourceRange(); 959 960 return false; 961 } 962 963 AssignConvertType ConvTy = CheckSingleAssignmentConstraints(DeclType, Init); 964 return DiagnoseAssignmentResult(ConvTy, Init->getLocStart(), DeclType, 965 InitType, Init, "initializing"); 966} 967 968bool Sema::CheckStringLiteralInit(StringLiteral *strLiteral, QualType &DeclT) { 969 const ArrayType *AT = Context.getAsArrayType(DeclT); 970 971 if (const IncompleteArrayType *IAT = dyn_cast<IncompleteArrayType>(AT)) { 972 // C99 6.7.8p14. We have an array of character type with unknown size 973 // being initialized to a string literal. 974 llvm::APSInt ConstVal(32); 975 ConstVal = strLiteral->getByteLength() + 1; 976 // Return a new array type (C99 6.7.8p22). 977 DeclT = Context.getConstantArrayType(IAT->getElementType(), ConstVal, 978 ArrayType::Normal, 0); 979 } else { 980 const ConstantArrayType *CAT = cast<ConstantArrayType>(AT); 981 // C99 6.7.8p14. We have an array of character type with known size. 982 // FIXME: Avoid truncation for 64-bit length strings. 983 if (strLiteral->getByteLength() > (unsigned)CAT->getSize().getZExtValue()) 984 Diag(strLiteral->getSourceRange().getBegin(), 985 diag::warn_initializer_string_for_char_array_too_long) 986 << strLiteral->getSourceRange(); 987 } 988 // Set type from "char *" to "constant array of char". 989 strLiteral->setType(DeclT); 990 // For now, we always return false (meaning success). 991 return false; 992} 993 994StringLiteral *Sema::IsStringLiteralInit(Expr *Init, QualType DeclType) { 995 const ArrayType *AT = Context.getAsArrayType(DeclType); 996 if (AT && AT->getElementType()->isCharType()) { 997 return dyn_cast<StringLiteral>(Init->IgnoreParens()); 998 } 999 return 0; 1000} 1001 1002bool Sema::CheckInitializerTypes(Expr *&Init, QualType &DeclType, 1003 SourceLocation InitLoc, 1004 DeclarationName InitEntity, 1005 bool DirectInit) { 1006 if (DeclType->isDependentType() || Init->isTypeDependent()) 1007 return false; 1008 1009 // C++ [dcl.init.ref]p1: 1010 // A variable declared to be a T&, that is "reference to type T" 1011 // (8.3.2), shall be initialized by an object, or function, of 1012 // type T or by an object that can be converted into a T. 1013 if (DeclType->isReferenceType()) 1014 return CheckReferenceInit(Init, DeclType, 0, false, DirectInit); 1015 1016 // C99 6.7.8p3: The type of the entity to be initialized shall be an array 1017 // of unknown size ("[]") or an object type that is not a variable array type. 1018 if (const VariableArrayType *VAT = Context.getAsVariableArrayType(DeclType)) 1019 return Diag(InitLoc, diag::err_variable_object_no_init) 1020 << VAT->getSizeExpr()->getSourceRange(); 1021 1022 InitListExpr *InitList = dyn_cast<InitListExpr>(Init); 1023 if (!InitList) { 1024 // FIXME: Handle wide strings 1025 if (StringLiteral *strLiteral = IsStringLiteralInit(Init, DeclType)) 1026 return CheckStringLiteralInit(strLiteral, DeclType); 1027 1028 // C++ [dcl.init]p14: 1029 // -- If the destination type is a (possibly cv-qualified) class 1030 // type: 1031 if (getLangOptions().CPlusPlus && DeclType->isRecordType()) { 1032 QualType DeclTypeC = Context.getCanonicalType(DeclType); 1033 QualType InitTypeC = Context.getCanonicalType(Init->getType()); 1034 1035 // -- If the initialization is direct-initialization, or if it is 1036 // copy-initialization where the cv-unqualified version of the 1037 // source type is the same class as, or a derived class of, the 1038 // class of the destination, constructors are considered. 1039 if ((DeclTypeC.getUnqualifiedType() == InitTypeC.getUnqualifiedType()) || 1040 IsDerivedFrom(InitTypeC, DeclTypeC)) { 1041 CXXConstructorDecl *Constructor 1042 = PerformInitializationByConstructor(DeclType, &Init, 1, 1043 InitLoc, Init->getSourceRange(), 1044 InitEntity, 1045 DirectInit? IK_Direct : IK_Copy); 1046 return Constructor == 0; 1047 } 1048 1049 // -- Otherwise (i.e., for the remaining copy-initialization 1050 // cases), user-defined conversion sequences that can 1051 // convert from the source type to the destination type or 1052 // (when a conversion function is used) to a derived class 1053 // thereof are enumerated as described in 13.3.1.4, and the 1054 // best one is chosen through overload resolution 1055 // (13.3). If the conversion cannot be done or is 1056 // ambiguous, the initialization is ill-formed. The 1057 // function selected is called with the initializer 1058 // expression as its argument; if the function is a 1059 // constructor, the call initializes a temporary of the 1060 // destination type. 1061 // FIXME: We're pretending to do copy elision here; return to 1062 // this when we have ASTs for such things. 1063 if (!PerformImplicitConversion(Init, DeclType, "initializing")) 1064 return false; 1065 1066 if (InitEntity) 1067 return Diag(InitLoc, diag::err_cannot_initialize_decl) 1068 << InitEntity << (int)(Init->isLvalue(Context) == Expr::LV_Valid) 1069 << Init->getType() << Init->getSourceRange(); 1070 else 1071 return Diag(InitLoc, diag::err_cannot_initialize_decl_noname) 1072 << DeclType << (int)(Init->isLvalue(Context) == Expr::LV_Valid) 1073 << Init->getType() << Init->getSourceRange(); 1074 } 1075 1076 // C99 6.7.8p16. 1077 if (DeclType->isArrayType()) 1078 return Diag(Init->getLocStart(), diag::err_array_init_list_required) 1079 << Init->getSourceRange(); 1080 1081 return CheckSingleInitializer(Init, DeclType, DirectInit); 1082 } 1083 1084 bool hadError = CheckInitList(InitList, DeclType); 1085 Init = InitList; 1086 return hadError; 1087} 1088 1089/// GetNameForDeclarator - Determine the full declaration name for the 1090/// given Declarator. 1091DeclarationName Sema::GetNameForDeclarator(Declarator &D) { 1092 switch (D.getKind()) { 1093 case Declarator::DK_Abstract: 1094 assert(D.getIdentifier() == 0 && "abstract declarators have no name"); 1095 return DeclarationName(); 1096 1097 case Declarator::DK_Normal: 1098 assert (D.getIdentifier() != 0 && "normal declarators have an identifier"); 1099 return DeclarationName(D.getIdentifier()); 1100 1101 case Declarator::DK_Constructor: { 1102 QualType Ty = Context.getTypeDeclType((TypeDecl *)D.getDeclaratorIdType()); 1103 Ty = Context.getCanonicalType(Ty); 1104 return Context.DeclarationNames.getCXXConstructorName(Ty); 1105 } 1106 1107 case Declarator::DK_Destructor: { 1108 QualType Ty = Context.getTypeDeclType((TypeDecl *)D.getDeclaratorIdType()); 1109 Ty = Context.getCanonicalType(Ty); 1110 return Context.DeclarationNames.getCXXDestructorName(Ty); 1111 } 1112 1113 case Declarator::DK_Conversion: { 1114 QualType Ty = QualType::getFromOpaquePtr(D.getDeclaratorIdType()); 1115 Ty = Context.getCanonicalType(Ty); 1116 return Context.DeclarationNames.getCXXConversionFunctionName(Ty); 1117 } 1118 1119 case Declarator::DK_Operator: 1120 assert(D.getIdentifier() == 0 && "operator names have no identifier"); 1121 return Context.DeclarationNames.getCXXOperatorName( 1122 D.getOverloadedOperator()); 1123 } 1124 1125 assert(false && "Unknown name kind"); 1126 return DeclarationName(); 1127} 1128 1129/// isNearlyMatchingMemberFunction - Determine whether the C++ member 1130/// functions Declaration and Definition are "nearly" matching. This 1131/// heuristic is used to improve diagnostics in the case where an 1132/// out-of-line member function definition doesn't match any 1133/// declaration within the class. 1134static bool isNearlyMatchingMemberFunction(ASTContext &Context, 1135 FunctionDecl *Declaration, 1136 FunctionDecl *Definition) { 1137 if (Declaration->param_size() != Definition->param_size()) 1138 return false; 1139 for (unsigned Idx = 0; Idx < Declaration->param_size(); ++Idx) { 1140 QualType DeclParamTy = Declaration->getParamDecl(Idx)->getType(); 1141 QualType DefParamTy = Definition->getParamDecl(Idx)->getType(); 1142 1143 DeclParamTy = Context.getCanonicalType(DeclParamTy.getNonReferenceType()); 1144 DefParamTy = Context.getCanonicalType(DefParamTy.getNonReferenceType()); 1145 if (DeclParamTy.getUnqualifiedType() != DefParamTy.getUnqualifiedType()) 1146 return false; 1147 } 1148 1149 return true; 1150} 1151 1152Sema::DeclTy * 1153Sema::ActOnDeclarator(Scope *S, Declarator &D, DeclTy *lastDecl, 1154 bool IsFunctionDefinition) { 1155 NamedDecl *LastDeclarator = dyn_cast_or_null<NamedDecl>((Decl *)lastDecl); 1156 DeclarationName Name = GetNameForDeclarator(D); 1157 1158 // All of these full declarators require an identifier. If it doesn't have 1159 // one, the ParsedFreeStandingDeclSpec action should be used. 1160 if (!Name) { 1161 if (!D.getInvalidType()) // Reject this if we think it is valid. 1162 Diag(D.getDeclSpec().getSourceRange().getBegin(), 1163 diag::err_declarator_need_ident) 1164 << D.getDeclSpec().getSourceRange() << D.getSourceRange(); 1165 return 0; 1166 } 1167 1168 // The scope passed in may not be a decl scope. Zip up the scope tree until 1169 // we find one that is. 1170 while ((S->getFlags() & Scope::DeclScope) == 0 || 1171 (S->getFlags() & Scope::TemplateParamScope) != 0) 1172 S = S->getParent(); 1173 1174 DeclContext *DC; 1175 Decl *PrevDecl; 1176 NamedDecl *New; 1177 bool InvalidDecl = false; 1178 1179 // See if this is a redefinition of a variable in the same scope. 1180 if (!D.getCXXScopeSpec().isSet() && !D.getCXXScopeSpec().isInvalid()) { 1181 DC = CurContext; 1182 PrevDecl = LookupName(S, Name, LookupOrdinaryName); 1183 } else { // Something like "int foo::x;" 1184 DC = static_cast<DeclContext*>(D.getCXXScopeSpec().getScopeRep()); 1185 PrevDecl = LookupQualifiedName(DC, Name, LookupOrdinaryName); 1186 1187 // C++ 7.3.1.2p2: 1188 // Members (including explicit specializations of templates) of a named 1189 // namespace can also be defined outside that namespace by explicit 1190 // qualification of the name being defined, provided that the entity being 1191 // defined was already declared in the namespace and the definition appears 1192 // after the point of declaration in a namespace that encloses the 1193 // declarations namespace. 1194 // 1195 // Note that we only check the context at this point. We don't yet 1196 // have enough information to make sure that PrevDecl is actually 1197 // the declaration we want to match. For example, given: 1198 // 1199 // class X { 1200 // void f(); 1201 // void f(float); 1202 // }; 1203 // 1204 // void X::f(int) { } // ill-formed 1205 // 1206 // In this case, PrevDecl will point to the overload set 1207 // containing the two f's declared in X, but neither of them 1208 // matches. 1209 if (!CurContext->Encloses(DC)) { 1210 // The qualifying scope doesn't enclose the original declaration. 1211 // Emit diagnostic based on current scope. 1212 SourceLocation L = D.getIdentifierLoc(); 1213 SourceRange R = D.getCXXScopeSpec().getRange(); 1214 if (isa<FunctionDecl>(CurContext)) { 1215 Diag(L, diag::err_invalid_declarator_in_function) << Name << R; 1216 } else { 1217 Diag(L, diag::err_invalid_declarator_scope) 1218 << Name << cast<NamedDecl>(DC)->getDeclName() << R; 1219 } 1220 InvalidDecl = true; 1221 } 1222 } 1223 1224 if (PrevDecl && PrevDecl->isTemplateParameter()) { 1225 // Maybe we will complain about the shadowed template parameter. 1226 InvalidDecl = InvalidDecl 1227 || DiagnoseTemplateParameterShadow(D.getIdentifierLoc(), PrevDecl); 1228 // Just pretend that we didn't see the previous declaration. 1229 PrevDecl = 0; 1230 } 1231 1232 // In C++, the previous declaration we find might be a tag type 1233 // (class or enum). In this case, the new declaration will hide the 1234 // tag type. Note that this does does not apply if we're declaring a 1235 // typedef (C++ [dcl.typedef]p4). 1236 if (PrevDecl && PrevDecl->getIdentifierNamespace() == Decl::IDNS_Tag && 1237 D.getDeclSpec().getStorageClassSpec() != DeclSpec::SCS_typedef) 1238 PrevDecl = 0; 1239 1240 QualType R = GetTypeForDeclarator(D, S); 1241 assert(!R.isNull() && "GetTypeForDeclarator() returned null type"); 1242 1243 if (D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_typedef) { 1244 New = ActOnTypedefDeclarator(S, D, DC, R, LastDeclarator, PrevDecl, 1245 InvalidDecl); 1246 } else if (R.getTypePtr()->isFunctionType()) { 1247 New = ActOnFunctionDeclarator(S, D, DC, R, LastDeclarator, PrevDecl, 1248 IsFunctionDefinition, InvalidDecl); 1249 } else { 1250 New = ActOnVariableDeclarator(S, D, DC, R, LastDeclarator, PrevDecl, 1251 InvalidDecl); 1252 } 1253 1254 if (New == 0) 1255 return 0; 1256 1257 // Set the lexical context. If the declarator has a C++ scope specifier, the 1258 // lexical context will be different from the semantic context. 1259 New->setLexicalDeclContext(CurContext); 1260 1261 // If this has an identifier, add it to the scope stack. 1262 if (Name) 1263 PushOnScopeChains(New, S); 1264 // If any semantic error occurred, mark the decl as invalid. 1265 if (D.getInvalidType() || InvalidDecl) 1266 New->setInvalidDecl(); 1267 1268 return New; 1269} 1270 1271NamedDecl* 1272Sema::ActOnTypedefDeclarator(Scope* S, Declarator& D, DeclContext* DC, 1273 QualType R, Decl* LastDeclarator, 1274 Decl* PrevDecl, bool& InvalidDecl) { 1275 // Typedef declarators cannot be qualified (C++ [dcl.meaning]p1). 1276 if (D.getCXXScopeSpec().isSet()) { 1277 Diag(D.getIdentifierLoc(), diag::err_qualified_typedef_declarator) 1278 << D.getCXXScopeSpec().getRange(); 1279 InvalidDecl = true; 1280 // Pretend we didn't see the scope specifier. 1281 DC = 0; 1282 } 1283 1284 // Check that there are no default arguments (C++ only). 1285 if (getLangOptions().CPlusPlus) 1286 CheckExtraCXXDefaultArguments(D); 1287 1288 TypedefDecl *NewTD = ParseTypedefDecl(S, D, R, LastDeclarator); 1289 if (!NewTD) return 0; 1290 1291 // Handle attributes prior to checking for duplicates in MergeVarDecl 1292 ProcessDeclAttributes(NewTD, D); 1293 // Merge the decl with the existing one if appropriate. If the decl is 1294 // in an outer scope, it isn't the same thing. 1295 if (PrevDecl && isDeclInScope(PrevDecl, DC, S)) { 1296 NewTD = MergeTypeDefDecl(NewTD, PrevDecl); 1297 if (NewTD == 0) return 0; 1298 } 1299 1300 if (S->getFnParent() == 0) { 1301 // C99 6.7.7p2: If a typedef name specifies a variably modified type 1302 // then it shall have block scope. 1303 if (NewTD->getUnderlyingType()->isVariablyModifiedType()) { 1304 if (NewTD->getUnderlyingType()->isVariableArrayType()) 1305 Diag(D.getIdentifierLoc(), diag::err_vla_decl_in_file_scope); 1306 else 1307 Diag(D.getIdentifierLoc(), diag::err_vm_decl_in_file_scope); 1308 1309 InvalidDecl = true; 1310 } 1311 } 1312 return NewTD; 1313} 1314 1315NamedDecl* 1316Sema::ActOnVariableDeclarator(Scope* S, Declarator& D, DeclContext* DC, 1317 QualType R, Decl* LastDeclarator, 1318 Decl* PrevDecl, bool& InvalidDecl) { 1319 DeclarationName Name = GetNameForDeclarator(D); 1320 1321 // Check that there are no default arguments (C++ only). 1322 if (getLangOptions().CPlusPlus) 1323 CheckExtraCXXDefaultArguments(D); 1324 1325 if (R.getTypePtr()->isObjCInterfaceType()) { 1326 Diag(D.getIdentifierLoc(), diag::err_statically_allocated_object) 1327 << D.getIdentifier(); 1328 InvalidDecl = true; 1329 } 1330 1331 VarDecl *NewVD; 1332 VarDecl::StorageClass SC; 1333 switch (D.getDeclSpec().getStorageClassSpec()) { 1334 default: assert(0 && "Unknown storage class!"); 1335 case DeclSpec::SCS_unspecified: SC = VarDecl::None; break; 1336 case DeclSpec::SCS_extern: SC = VarDecl::Extern; break; 1337 case DeclSpec::SCS_static: SC = VarDecl::Static; break; 1338 case DeclSpec::SCS_auto: SC = VarDecl::Auto; break; 1339 case DeclSpec::SCS_register: SC = VarDecl::Register; break; 1340 case DeclSpec::SCS_private_extern: SC = VarDecl::PrivateExtern; break; 1341 case DeclSpec::SCS_mutable: 1342 // mutable can only appear on non-static class members, so it's always 1343 // an error here 1344 Diag(D.getIdentifierLoc(), diag::err_mutable_nonmember); 1345 InvalidDecl = true; 1346 SC = VarDecl::None; 1347 break; 1348 } 1349 1350 IdentifierInfo *II = Name.getAsIdentifierInfo(); 1351 if (!II) { 1352 Diag(D.getIdentifierLoc(), diag::err_bad_variable_name) 1353 << Name.getAsString(); 1354 return 0; 1355 } 1356 1357 if (DC->isRecord()) { 1358 // This is a static data member for a C++ class. 1359 NewVD = CXXClassVarDecl::Create(Context, cast<CXXRecordDecl>(DC), 1360 D.getIdentifierLoc(), II, 1361 R); 1362 } else { 1363 bool ThreadSpecified = D.getDeclSpec().isThreadSpecified(); 1364 if (S->getFnParent() == 0) { 1365 // C99 6.9p2: The storage-class specifiers auto and register shall not 1366 // appear in the declaration specifiers in an external declaration. 1367 if (SC == VarDecl::Auto || SC == VarDecl::Register) { 1368 Diag(D.getIdentifierLoc(), diag::err_typecheck_sclass_fscope); 1369 InvalidDecl = true; 1370 } 1371 } 1372 NewVD = VarDecl::Create(Context, DC, D.getIdentifierLoc(), 1373 II, R, SC, 1374 // FIXME: Move to DeclGroup... 1375 D.getDeclSpec().getSourceRange().getBegin()); 1376 NewVD->setThreadSpecified(ThreadSpecified); 1377 } 1378 NewVD->setNextDeclarator(LastDeclarator); 1379 1380 // Handle attributes prior to checking for duplicates in MergeVarDecl 1381 ProcessDeclAttributes(NewVD, D); 1382 1383 // Handle GNU asm-label extension (encoded as an attribute). 1384 if (Expr *E = (Expr*) D.getAsmLabel()) { 1385 // The parser guarantees this is a string. 1386 StringLiteral *SE = cast<StringLiteral>(E); 1387 NewVD->addAttr(new AsmLabelAttr(std::string(SE->getStrData(), 1388 SE->getByteLength()))); 1389 } 1390 1391 // Emit an error if an address space was applied to decl with local storage. 1392 // This includes arrays of objects with address space qualifiers, but not 1393 // automatic variables that point to other address spaces. 1394 // ISO/IEC TR 18037 S5.1.2 1395 if (NewVD->hasLocalStorage() && (NewVD->getType().getAddressSpace() != 0)) { 1396 Diag(D.getIdentifierLoc(), diag::err_as_qualified_auto_decl); 1397 InvalidDecl = true; 1398 } 1399 // Merge the decl with the existing one if appropriate. If the decl is 1400 // in an outer scope, it isn't the same thing. 1401 if (PrevDecl && isDeclInScope(PrevDecl, DC, S)) { 1402 if (isa<FieldDecl>(PrevDecl) && D.getCXXScopeSpec().isSet()) { 1403 // The user tried to define a non-static data member 1404 // out-of-line (C++ [dcl.meaning]p1). 1405 Diag(NewVD->getLocation(), diag::err_nonstatic_member_out_of_line) 1406 << D.getCXXScopeSpec().getRange(); 1407 NewVD->Destroy(Context); 1408 return 0; 1409 } 1410 1411 NewVD = MergeVarDecl(NewVD, PrevDecl); 1412 if (NewVD == 0) return 0; 1413 1414 if (D.getCXXScopeSpec().isSet()) { 1415 // No previous declaration in the qualifying scope. 1416 Diag(D.getIdentifierLoc(), diag::err_typecheck_no_member) 1417 << Name << D.getCXXScopeSpec().getRange(); 1418 InvalidDecl = true; 1419 } 1420 } 1421 return NewVD; 1422} 1423 1424NamedDecl* 1425Sema::ActOnFunctionDeclarator(Scope* S, Declarator& D, DeclContext* DC, 1426 QualType R, Decl *LastDeclarator, 1427 Decl* PrevDecl, bool IsFunctionDefinition, 1428 bool& InvalidDecl) { 1429 assert(R.getTypePtr()->isFunctionType()); 1430 1431 DeclarationName Name = GetNameForDeclarator(D); 1432 FunctionDecl::StorageClass SC = FunctionDecl::None; 1433 switch (D.getDeclSpec().getStorageClassSpec()) { 1434 default: assert(0 && "Unknown storage class!"); 1435 case DeclSpec::SCS_auto: 1436 case DeclSpec::SCS_register: 1437 case DeclSpec::SCS_mutable: 1438 Diag(D.getIdentifierLoc(), diag::err_typecheck_sclass_func); 1439 InvalidDecl = true; 1440 break; 1441 case DeclSpec::SCS_unspecified: SC = FunctionDecl::None; break; 1442 case DeclSpec::SCS_extern: SC = FunctionDecl::Extern; break; 1443 case DeclSpec::SCS_static: SC = FunctionDecl::Static; break; 1444 case DeclSpec::SCS_private_extern: SC = FunctionDecl::PrivateExtern;break; 1445 } 1446 1447 bool isInline = D.getDeclSpec().isInlineSpecified(); 1448 // bool isVirtual = D.getDeclSpec().isVirtualSpecified(); 1449 bool isExplicit = D.getDeclSpec().isExplicitSpecified(); 1450 1451 FunctionDecl *NewFD; 1452 if (D.getKind() == Declarator::DK_Constructor) { 1453 // This is a C++ constructor declaration. 1454 assert(DC->isRecord() && 1455 "Constructors can only be declared in a member context"); 1456 1457 InvalidDecl = InvalidDecl || CheckConstructorDeclarator(D, R, SC); 1458 1459 // Create the new declaration 1460 NewFD = CXXConstructorDecl::Create(Context, 1461 cast<CXXRecordDecl>(DC), 1462 D.getIdentifierLoc(), Name, R, 1463 isExplicit, isInline, 1464 /*isImplicitlyDeclared=*/false); 1465 1466 if (InvalidDecl) 1467 NewFD->setInvalidDecl(); 1468 } else if (D.getKind() == Declarator::DK_Destructor) { 1469 // This is a C++ destructor declaration. 1470 if (DC->isRecord()) { 1471 InvalidDecl = InvalidDecl || CheckDestructorDeclarator(D, R, SC); 1472 1473 NewFD = CXXDestructorDecl::Create(Context, 1474 cast<CXXRecordDecl>(DC), 1475 D.getIdentifierLoc(), Name, R, 1476 isInline, 1477 /*isImplicitlyDeclared=*/false); 1478 1479 if (InvalidDecl) 1480 NewFD->setInvalidDecl(); 1481 } else { 1482 Diag(D.getIdentifierLoc(), diag::err_destructor_not_member); 1483 1484 // Create a FunctionDecl to satisfy the function definition parsing 1485 // code path. 1486 NewFD = FunctionDecl::Create(Context, DC, D.getIdentifierLoc(), 1487 Name, R, SC, isInline, 1488 // FIXME: Move to DeclGroup... 1489 D.getDeclSpec().getSourceRange().getBegin()); 1490 InvalidDecl = true; 1491 NewFD->setInvalidDecl(); 1492 } 1493 } else if (D.getKind() == Declarator::DK_Conversion) { 1494 if (!DC->isRecord()) { 1495 Diag(D.getIdentifierLoc(), 1496 diag::err_conv_function_not_member); 1497 return 0; 1498 } else { 1499 InvalidDecl = InvalidDecl || CheckConversionDeclarator(D, R, SC); 1500 1501 NewFD = CXXConversionDecl::Create(Context, cast<CXXRecordDecl>(DC), 1502 D.getIdentifierLoc(), Name, R, 1503 isInline, isExplicit); 1504 1505 if (InvalidDecl) 1506 NewFD->setInvalidDecl(); 1507 } 1508 } else if (DC->isRecord()) { 1509 // This is a C++ method declaration. 1510 NewFD = CXXMethodDecl::Create(Context, cast<CXXRecordDecl>(DC), 1511 D.getIdentifierLoc(), Name, R, 1512 (SC == FunctionDecl::Static), isInline); 1513 } else { 1514 NewFD = FunctionDecl::Create(Context, DC, 1515 D.getIdentifierLoc(), 1516 Name, R, SC, isInline, 1517 // FIXME: Move to DeclGroup... 1518 D.getDeclSpec().getSourceRange().getBegin()); 1519 } 1520 NewFD->setNextDeclarator(LastDeclarator); 1521 1522 // Set the lexical context. If the declarator has a C++ 1523 // scope specifier, the lexical context will be different 1524 // from the semantic context. 1525 NewFD->setLexicalDeclContext(CurContext); 1526 1527 // Handle GNU asm-label extension (encoded as an attribute). 1528 if (Expr *E = (Expr*) D.getAsmLabel()) { 1529 // The parser guarantees this is a string. 1530 StringLiteral *SE = cast<StringLiteral>(E); 1531 NewFD->addAttr(new AsmLabelAttr(std::string(SE->getStrData(), 1532 SE->getByteLength()))); 1533 } 1534 1535 // Copy the parameter declarations from the declarator D to 1536 // the function declaration NewFD, if they are available. 1537 if (D.getNumTypeObjects() > 0) { 1538 DeclaratorChunk::FunctionTypeInfo &FTI = D.getTypeObject(0).Fun; 1539 1540 // Create Decl objects for each parameter, adding them to the 1541 // FunctionDecl. 1542 llvm::SmallVector<ParmVarDecl*, 16> Params; 1543 1544 // Check for C99 6.7.5.3p10 - foo(void) is a non-varargs 1545 // function that takes no arguments, not a function that takes a 1546 // single void argument. 1547 // We let through "const void" here because Sema::GetTypeForDeclarator 1548 // already checks for that case. 1549 if (FTI.NumArgs == 1 && !FTI.isVariadic && FTI.ArgInfo[0].Ident == 0 && 1550 FTI.ArgInfo[0].Param && 1551 ((ParmVarDecl*)FTI.ArgInfo[0].Param)->getType()->isVoidType()) { 1552 // empty arg list, don't push any params. 1553 ParmVarDecl *Param = (ParmVarDecl*)FTI.ArgInfo[0].Param; 1554 1555 // In C++, the empty parameter-type-list must be spelled "void"; a 1556 // typedef of void is not permitted. 1557 if (getLangOptions().CPlusPlus && 1558 Param->getType().getUnqualifiedType() != Context.VoidTy) { 1559 Diag(Param->getLocation(), diag::ext_param_typedef_of_void); 1560 } 1561 } else if (FTI.NumArgs > 0 && FTI.ArgInfo[0].Param != 0) { 1562 for (unsigned i = 0, e = FTI.NumArgs; i != e; ++i) 1563 Params.push_back((ParmVarDecl *)FTI.ArgInfo[i].Param); 1564 } 1565 1566 NewFD->setParams(Context, &Params[0], Params.size()); 1567 } else if (R->getAsTypedefType()) { 1568 // When we're declaring a function with a typedef, as in the 1569 // following example, we'll need to synthesize (unnamed) 1570 // parameters for use in the declaration. 1571 // 1572 // @code 1573 // typedef void fn(int); 1574 // fn f; 1575 // @endcode 1576 const FunctionTypeProto *FT = R->getAsFunctionTypeProto(); 1577 if (!FT) { 1578 // This is a typedef of a function with no prototype, so we 1579 // don't need to do anything. 1580 } else if ((FT->getNumArgs() == 0) || 1581 (FT->getNumArgs() == 1 && !FT->isVariadic() && 1582 FT->getArgType(0)->isVoidType())) { 1583 // This is a zero-argument function. We don't need to do anything. 1584 } else { 1585 // Synthesize a parameter for each argument type. 1586 llvm::SmallVector<ParmVarDecl*, 16> Params; 1587 for (FunctionTypeProto::arg_type_iterator ArgType = FT->arg_type_begin(); 1588 ArgType != FT->arg_type_end(); ++ArgType) { 1589 Params.push_back(ParmVarDecl::Create(Context, DC, 1590 SourceLocation(), 0, 1591 *ArgType, VarDecl::None, 1592 0)); 1593 } 1594 1595 NewFD->setParams(Context, &Params[0], Params.size()); 1596 } 1597 } 1598 1599 if (CXXConstructorDecl *Constructor = dyn_cast<CXXConstructorDecl>(NewFD)) 1600 InvalidDecl = InvalidDecl || CheckConstructor(Constructor); 1601 else if (isa<CXXDestructorDecl>(NewFD)) { 1602 CXXRecordDecl *Record = cast<CXXRecordDecl>(NewFD->getParent()); 1603 Record->setUserDeclaredDestructor(true); 1604 // C++ [class]p4: A POD-struct is an aggregate class that has [...] no 1605 // user-defined destructor. 1606 Record->setPOD(false); 1607 } else if (CXXConversionDecl *Conversion = 1608 dyn_cast<CXXConversionDecl>(NewFD)) 1609 ActOnConversionDeclarator(Conversion); 1610 1611 // Extra checking for C++ overloaded operators (C++ [over.oper]). 1612 if (NewFD->isOverloadedOperator() && 1613 CheckOverloadedOperatorDeclaration(NewFD)) 1614 NewFD->setInvalidDecl(); 1615 1616 // Merge the decl with the existing one if appropriate. Since C functions 1617 // are in a flat namespace, make sure we consider decls in outer scopes. 1618 if (PrevDecl && 1619 (!getLangOptions().CPlusPlus||isDeclInScope(PrevDecl, DC, S))) { 1620 bool Redeclaration = false; 1621 1622 // If C++, determine whether NewFD is an overload of PrevDecl or 1623 // a declaration that requires merging. If it's an overload, 1624 // there's no more work to do here; we'll just add the new 1625 // function to the scope. 1626 OverloadedFunctionDecl::function_iterator MatchedDecl; 1627 if (!getLangOptions().CPlusPlus || 1628 !IsOverload(NewFD, PrevDecl, MatchedDecl)) { 1629 Decl *OldDecl = PrevDecl; 1630 1631 // If PrevDecl was an overloaded function, extract the 1632 // FunctionDecl that matched. 1633 if (isa<OverloadedFunctionDecl>(PrevDecl)) 1634 OldDecl = *MatchedDecl; 1635 1636 // NewFD and PrevDecl represent declarations that need to be 1637 // merged. 1638 NewFD = MergeFunctionDecl(NewFD, OldDecl, Redeclaration); 1639 1640 if (NewFD == 0) return 0; 1641 if (Redeclaration) { 1642 NewFD->setPreviousDeclaration(cast<FunctionDecl>(OldDecl)); 1643 1644 // An out-of-line member function declaration must also be a 1645 // definition (C++ [dcl.meaning]p1). 1646 if (!IsFunctionDefinition && D.getCXXScopeSpec().isSet() && 1647 !InvalidDecl) { 1648 Diag(NewFD->getLocation(), diag::err_out_of_line_declaration) 1649 << D.getCXXScopeSpec().getRange(); 1650 NewFD->setInvalidDecl(); 1651 } 1652 } 1653 } 1654 1655 if (!Redeclaration && D.getCXXScopeSpec().isSet()) { 1656 // The user tried to provide an out-of-line definition for a 1657 // member function, but there was no such member function 1658 // declared (C++ [class.mfct]p2). For example: 1659 // 1660 // class X { 1661 // void f() const; 1662 // }; 1663 // 1664 // void X::f() { } // ill-formed 1665 // 1666 // Complain about this problem, and attempt to suggest close 1667 // matches (e.g., those that differ only in cv-qualifiers and 1668 // whether the parameter types are references). 1669 Diag(D.getIdentifierLoc(), diag::err_member_def_does_not_match) 1670 << cast<CXXRecordDecl>(DC)->getDeclName() 1671 << D.getCXXScopeSpec().getRange(); 1672 InvalidDecl = true; 1673 1674 LookupResult Prev = LookupQualifiedName(DC, Name, LookupOrdinaryName, 1675 true); 1676 assert(!Prev.isAmbiguous() && 1677 "Cannot have an ambiguity in previous-declaration lookup"); 1678 for (LookupResult::iterator Func = Prev.begin(), FuncEnd = Prev.end(); 1679 Func != FuncEnd; ++Func) { 1680 if (isa<CXXMethodDecl>(*Func) && 1681 isNearlyMatchingMemberFunction(Context, cast<FunctionDecl>(*Func), 1682 NewFD)) 1683 Diag((*Func)->getLocation(), diag::note_member_def_close_match); 1684 } 1685 1686 PrevDecl = 0; 1687 } 1688 } 1689 1690 // Handle attributes. We need to have merged decls when handling attributes 1691 // (for example to check for conflicts, etc). 1692 ProcessDeclAttributes(NewFD, D); 1693 1694 if (getLangOptions().CPlusPlus) { 1695 // In C++, check default arguments now that we have merged decls. 1696 CheckCXXDefaultArguments(NewFD); 1697 1698 // An out-of-line member function declaration must also be a 1699 // definition (C++ [dcl.meaning]p1). 1700 if (!IsFunctionDefinition && D.getCXXScopeSpec().isSet() && !InvalidDecl) { 1701 Diag(NewFD->getLocation(), diag::err_out_of_line_declaration) 1702 << D.getCXXScopeSpec().getRange(); 1703 InvalidDecl = true; 1704 } 1705 } 1706 return NewFD; 1707} 1708 1709void Sema::InitializerElementNotConstant(const Expr *Init) { 1710 Diag(Init->getExprLoc(), diag::err_init_element_not_constant) 1711 << Init->getSourceRange(); 1712} 1713 1714bool Sema::CheckAddressConstantExpressionLValue(const Expr* Init) { 1715 switch (Init->getStmtClass()) { 1716 default: 1717 InitializerElementNotConstant(Init); 1718 return true; 1719 case Expr::ParenExprClass: { 1720 const ParenExpr* PE = cast<ParenExpr>(Init); 1721 return CheckAddressConstantExpressionLValue(PE->getSubExpr()); 1722 } 1723 case Expr::CompoundLiteralExprClass: 1724 return cast<CompoundLiteralExpr>(Init)->isFileScope(); 1725 case Expr::DeclRefExprClass: 1726 case Expr::QualifiedDeclRefExprClass: { 1727 const Decl *D = cast<DeclRefExpr>(Init)->getDecl(); 1728 if (const VarDecl *VD = dyn_cast<VarDecl>(D)) { 1729 if (VD->hasGlobalStorage()) 1730 return false; 1731 InitializerElementNotConstant(Init); 1732 return true; 1733 } 1734 if (isa<FunctionDecl>(D)) 1735 return false; 1736 InitializerElementNotConstant(Init); 1737 return true; 1738 } 1739 case Expr::MemberExprClass: { 1740 const MemberExpr *M = cast<MemberExpr>(Init); 1741 if (M->isArrow()) 1742 return CheckAddressConstantExpression(M->getBase()); 1743 return CheckAddressConstantExpressionLValue(M->getBase()); 1744 } 1745 case Expr::ArraySubscriptExprClass: { 1746 // FIXME: Should we pedwarn for "x[0+0]" (where x is a pointer)? 1747 const ArraySubscriptExpr *ASE = cast<ArraySubscriptExpr>(Init); 1748 return CheckAddressConstantExpression(ASE->getBase()) || 1749 CheckArithmeticConstantExpression(ASE->getIdx()); 1750 } 1751 case Expr::StringLiteralClass: 1752 case Expr::PredefinedExprClass: 1753 return false; 1754 case Expr::UnaryOperatorClass: { 1755 const UnaryOperator *Exp = cast<UnaryOperator>(Init); 1756 1757 // C99 6.6p9 1758 if (Exp->getOpcode() == UnaryOperator::Deref) 1759 return CheckAddressConstantExpression(Exp->getSubExpr()); 1760 1761 InitializerElementNotConstant(Init); 1762 return true; 1763 } 1764 } 1765} 1766 1767bool Sema::CheckAddressConstantExpression(const Expr* Init) { 1768 switch (Init->getStmtClass()) { 1769 default: 1770 InitializerElementNotConstant(Init); 1771 return true; 1772 case Expr::ParenExprClass: 1773 return CheckAddressConstantExpression(cast<ParenExpr>(Init)->getSubExpr()); 1774 case Expr::StringLiteralClass: 1775 case Expr::ObjCStringLiteralClass: 1776 return false; 1777 case Expr::CallExprClass: 1778 case Expr::CXXOperatorCallExprClass: 1779 // __builtin___CFStringMakeConstantString is a valid constant l-value. 1780 if (cast<CallExpr>(Init)->isBuiltinCall() == 1781 Builtin::BI__builtin___CFStringMakeConstantString) 1782 return false; 1783 1784 InitializerElementNotConstant(Init); 1785 return true; 1786 1787 case Expr::UnaryOperatorClass: { 1788 const UnaryOperator *Exp = cast<UnaryOperator>(Init); 1789 1790 // C99 6.6p9 1791 if (Exp->getOpcode() == UnaryOperator::AddrOf) 1792 return CheckAddressConstantExpressionLValue(Exp->getSubExpr()); 1793 1794 if (Exp->getOpcode() == UnaryOperator::Extension) 1795 return CheckAddressConstantExpression(Exp->getSubExpr()); 1796 1797 InitializerElementNotConstant(Init); 1798 return true; 1799 } 1800 case Expr::BinaryOperatorClass: { 1801 // FIXME: Should we pedwarn for expressions like "a + 1 + 2"? 1802 const BinaryOperator *Exp = cast<BinaryOperator>(Init); 1803 1804 Expr *PExp = Exp->getLHS(); 1805 Expr *IExp = Exp->getRHS(); 1806 if (IExp->getType()->isPointerType()) 1807 std::swap(PExp, IExp); 1808 1809 // FIXME: Should we pedwarn if IExp isn't an integer constant expression? 1810 return CheckAddressConstantExpression(PExp) || 1811 CheckArithmeticConstantExpression(IExp); 1812 } 1813 case Expr::ImplicitCastExprClass: 1814 case Expr::CStyleCastExprClass: { 1815 const Expr* SubExpr = cast<CastExpr>(Init)->getSubExpr(); 1816 if (Init->getStmtClass() == Expr::ImplicitCastExprClass) { 1817 // Check for implicit promotion 1818 if (SubExpr->getType()->isFunctionType() || 1819 SubExpr->getType()->isArrayType()) 1820 return CheckAddressConstantExpressionLValue(SubExpr); 1821 } 1822 1823 // Check for pointer->pointer cast 1824 if (SubExpr->getType()->isPointerType()) 1825 return CheckAddressConstantExpression(SubExpr); 1826 1827 if (SubExpr->getType()->isIntegralType()) { 1828 // Check for the special-case of a pointer->int->pointer cast; 1829 // this isn't standard, but some code requires it. See 1830 // PR2720 for an example. 1831 if (const CastExpr* SubCast = dyn_cast<CastExpr>(SubExpr)) { 1832 if (SubCast->getSubExpr()->getType()->isPointerType()) { 1833 unsigned IntWidth = Context.getIntWidth(SubCast->getType()); 1834 unsigned PointerWidth = Context.getTypeSize(Context.VoidPtrTy); 1835 if (IntWidth >= PointerWidth) { 1836 return CheckAddressConstantExpression(SubCast->getSubExpr()); 1837 } 1838 } 1839 } 1840 } 1841 if (SubExpr->getType()->isArithmeticType()) { 1842 return CheckArithmeticConstantExpression(SubExpr); 1843 } 1844 1845 InitializerElementNotConstant(Init); 1846 return true; 1847 } 1848 case Expr::ConditionalOperatorClass: { 1849 // FIXME: Should we pedwarn here? 1850 const ConditionalOperator *Exp = cast<ConditionalOperator>(Init); 1851 if (!Exp->getCond()->getType()->isArithmeticType()) { 1852 InitializerElementNotConstant(Init); 1853 return true; 1854 } 1855 if (CheckArithmeticConstantExpression(Exp->getCond())) 1856 return true; 1857 if (Exp->getLHS() && 1858 CheckAddressConstantExpression(Exp->getLHS())) 1859 return true; 1860 return CheckAddressConstantExpression(Exp->getRHS()); 1861 } 1862 case Expr::AddrLabelExprClass: 1863 return false; 1864 } 1865} 1866 1867static const Expr* FindExpressionBaseAddress(const Expr* E); 1868 1869static const Expr* FindExpressionBaseAddressLValue(const Expr* E) { 1870 switch (E->getStmtClass()) { 1871 default: 1872 return E; 1873 case Expr::ParenExprClass: { 1874 const ParenExpr* PE = cast<ParenExpr>(E); 1875 return FindExpressionBaseAddressLValue(PE->getSubExpr()); 1876 } 1877 case Expr::MemberExprClass: { 1878 const MemberExpr *M = cast<MemberExpr>(E); 1879 if (M->isArrow()) 1880 return FindExpressionBaseAddress(M->getBase()); 1881 return FindExpressionBaseAddressLValue(M->getBase()); 1882 } 1883 case Expr::ArraySubscriptExprClass: { 1884 const ArraySubscriptExpr *ASE = cast<ArraySubscriptExpr>(E); 1885 return FindExpressionBaseAddress(ASE->getBase()); 1886 } 1887 case Expr::UnaryOperatorClass: { 1888 const UnaryOperator *Exp = cast<UnaryOperator>(E); 1889 1890 if (Exp->getOpcode() == UnaryOperator::Deref) 1891 return FindExpressionBaseAddress(Exp->getSubExpr()); 1892 1893 return E; 1894 } 1895 } 1896} 1897 1898static const Expr* FindExpressionBaseAddress(const Expr* E) { 1899 switch (E->getStmtClass()) { 1900 default: 1901 return E; 1902 case Expr::ParenExprClass: { 1903 const ParenExpr* PE = cast<ParenExpr>(E); 1904 return FindExpressionBaseAddress(PE->getSubExpr()); 1905 } 1906 case Expr::UnaryOperatorClass: { 1907 const UnaryOperator *Exp = cast<UnaryOperator>(E); 1908 1909 // C99 6.6p9 1910 if (Exp->getOpcode() == UnaryOperator::AddrOf) 1911 return FindExpressionBaseAddressLValue(Exp->getSubExpr()); 1912 1913 if (Exp->getOpcode() == UnaryOperator::Extension) 1914 return FindExpressionBaseAddress(Exp->getSubExpr()); 1915 1916 return E; 1917 } 1918 case Expr::BinaryOperatorClass: { 1919 const BinaryOperator *Exp = cast<BinaryOperator>(E); 1920 1921 Expr *PExp = Exp->getLHS(); 1922 Expr *IExp = Exp->getRHS(); 1923 if (IExp->getType()->isPointerType()) 1924 std::swap(PExp, IExp); 1925 1926 return FindExpressionBaseAddress(PExp); 1927 } 1928 case Expr::ImplicitCastExprClass: { 1929 const Expr* SubExpr = cast<ImplicitCastExpr>(E)->getSubExpr(); 1930 1931 // Check for implicit promotion 1932 if (SubExpr->getType()->isFunctionType() || 1933 SubExpr->getType()->isArrayType()) 1934 return FindExpressionBaseAddressLValue(SubExpr); 1935 1936 // Check for pointer->pointer cast 1937 if (SubExpr->getType()->isPointerType()) 1938 return FindExpressionBaseAddress(SubExpr); 1939 1940 // We assume that we have an arithmetic expression here; 1941 // if we don't, we'll figure it out later 1942 return 0; 1943 } 1944 case Expr::CStyleCastExprClass: { 1945 const Expr* SubExpr = cast<CastExpr>(E)->getSubExpr(); 1946 1947 // Check for pointer->pointer cast 1948 if (SubExpr->getType()->isPointerType()) 1949 return FindExpressionBaseAddress(SubExpr); 1950 1951 // We assume that we have an arithmetic expression here; 1952 // if we don't, we'll figure it out later 1953 return 0; 1954 } 1955 } 1956} 1957 1958bool Sema::CheckArithmeticConstantExpression(const Expr* Init) { 1959 switch (Init->getStmtClass()) { 1960 default: 1961 InitializerElementNotConstant(Init); 1962 return true; 1963 case Expr::ParenExprClass: { 1964 const ParenExpr* PE = cast<ParenExpr>(Init); 1965 return CheckArithmeticConstantExpression(PE->getSubExpr()); 1966 } 1967 case Expr::FloatingLiteralClass: 1968 case Expr::IntegerLiteralClass: 1969 case Expr::CharacterLiteralClass: 1970 case Expr::ImaginaryLiteralClass: 1971 case Expr::TypesCompatibleExprClass: 1972 case Expr::CXXBoolLiteralExprClass: 1973 return false; 1974 case Expr::CallExprClass: 1975 case Expr::CXXOperatorCallExprClass: { 1976 const CallExpr *CE = cast<CallExpr>(Init); 1977 1978 // Allow any constant foldable calls to builtins. 1979 if (CE->isBuiltinCall() && CE->isEvaluatable(Context)) 1980 return false; 1981 1982 InitializerElementNotConstant(Init); 1983 return true; 1984 } 1985 case Expr::DeclRefExprClass: 1986 case Expr::QualifiedDeclRefExprClass: { 1987 const Decl *D = cast<DeclRefExpr>(Init)->getDecl(); 1988 if (isa<EnumConstantDecl>(D)) 1989 return false; 1990 InitializerElementNotConstant(Init); 1991 return true; 1992 } 1993 case Expr::CompoundLiteralExprClass: 1994 // Allow "(vector type){2,4}"; normal C constraints don't allow this, 1995 // but vectors are allowed to be magic. 1996 if (Init->getType()->isVectorType()) 1997 return false; 1998 InitializerElementNotConstant(Init); 1999 return true; 2000 case Expr::UnaryOperatorClass: { 2001 const UnaryOperator *Exp = cast<UnaryOperator>(Init); 2002 2003 switch (Exp->getOpcode()) { 2004 // Address, indirect, pre/post inc/dec, etc are not valid constant exprs. 2005 // See C99 6.6p3. 2006 default: 2007 InitializerElementNotConstant(Init); 2008 return true; 2009 case UnaryOperator::OffsetOf: 2010 if (Exp->getSubExpr()->getType()->isConstantSizeType()) 2011 return false; 2012 InitializerElementNotConstant(Init); 2013 return true; 2014 case UnaryOperator::Extension: 2015 case UnaryOperator::LNot: 2016 case UnaryOperator::Plus: 2017 case UnaryOperator::Minus: 2018 case UnaryOperator::Not: 2019 return CheckArithmeticConstantExpression(Exp->getSubExpr()); 2020 } 2021 } 2022 case Expr::SizeOfAlignOfExprClass: { 2023 const SizeOfAlignOfExpr *Exp = cast<SizeOfAlignOfExpr>(Init); 2024 // Special check for void types, which are allowed as an extension 2025 if (Exp->getTypeOfArgument()->isVoidType()) 2026 return false; 2027 // alignof always evaluates to a constant. 2028 // FIXME: is sizeof(int[3.0]) a constant expression? 2029 if (Exp->isSizeOf() && !Exp->getTypeOfArgument()->isConstantSizeType()) { 2030 InitializerElementNotConstant(Init); 2031 return true; 2032 } 2033 return false; 2034 } 2035 case Expr::BinaryOperatorClass: { 2036 const BinaryOperator *Exp = cast<BinaryOperator>(Init); 2037 2038 if (Exp->getLHS()->getType()->isArithmeticType() && 2039 Exp->getRHS()->getType()->isArithmeticType()) { 2040 return CheckArithmeticConstantExpression(Exp->getLHS()) || 2041 CheckArithmeticConstantExpression(Exp->getRHS()); 2042 } 2043 2044 if (Exp->getLHS()->getType()->isPointerType() && 2045 Exp->getRHS()->getType()->isPointerType()) { 2046 const Expr* LHSBase = FindExpressionBaseAddress(Exp->getLHS()); 2047 const Expr* RHSBase = FindExpressionBaseAddress(Exp->getRHS()); 2048 2049 // Only allow a null (constant integer) base; we could 2050 // allow some additional cases if necessary, but this 2051 // is sufficient to cover offsetof-like constructs. 2052 if (!LHSBase && !RHSBase) { 2053 return CheckAddressConstantExpression(Exp->getLHS()) || 2054 CheckAddressConstantExpression(Exp->getRHS()); 2055 } 2056 } 2057 2058 InitializerElementNotConstant(Init); 2059 return true; 2060 } 2061 case Expr::ImplicitCastExprClass: 2062 case Expr::CStyleCastExprClass: { 2063 const CastExpr *CE = cast<CastExpr>(Init); 2064 const Expr *SubExpr = CE->getSubExpr(); 2065 2066 if (SubExpr->getType()->isArithmeticType()) 2067 return CheckArithmeticConstantExpression(SubExpr); 2068 2069 if (SubExpr->getType()->isPointerType()) { 2070 const Expr* Base = FindExpressionBaseAddress(SubExpr); 2071 if (Base) { 2072 // the cast is only valid if done to a wide enough type 2073 if (Context.getTypeSize(CE->getType()) >= 2074 Context.getTypeSize(SubExpr->getType())) 2075 return false; 2076 } else { 2077 // If the pointer has a null base, this is an offsetof-like construct 2078 return CheckAddressConstantExpression(SubExpr); 2079 } 2080 } 2081 2082 InitializerElementNotConstant(Init); 2083 return true; 2084 } 2085 case Expr::ConditionalOperatorClass: { 2086 const ConditionalOperator *Exp = cast<ConditionalOperator>(Init); 2087 2088 // If GNU extensions are disabled, we require all operands to be arithmetic 2089 // constant expressions. 2090 if (getLangOptions().NoExtensions) { 2091 return CheckArithmeticConstantExpression(Exp->getCond()) || 2092 (Exp->getLHS() && CheckArithmeticConstantExpression(Exp->getLHS())) || 2093 CheckArithmeticConstantExpression(Exp->getRHS()); 2094 } 2095 2096 // Otherwise, we have to emulate some of the behavior of fold here. 2097 // Basically GCC treats things like "4 ? 1 : somefunc()" as a constant 2098 // because it can constant fold things away. To retain compatibility with 2099 // GCC code, we see if we can fold the condition to a constant (which we 2100 // should always be able to do in theory). If so, we only require the 2101 // specified arm of the conditional to be a constant. This is a horrible 2102 // hack, but is require by real world code that uses __builtin_constant_p. 2103 Expr::EvalResult EvalResult; 2104 if (!Exp->getCond()->Evaluate(EvalResult, Context) || 2105 EvalResult.HasSideEffects) { 2106 // If Evaluate couldn't fold it, CheckArithmeticConstantExpression 2107 // won't be able to either. Use it to emit the diagnostic though. 2108 bool Res = CheckArithmeticConstantExpression(Exp->getCond()); 2109 assert(Res && "Evaluate couldn't evaluate this constant?"); 2110 return Res; 2111 } 2112 2113 // Verify that the side following the condition is also a constant. 2114 const Expr *TrueSide = Exp->getLHS(), *FalseSide = Exp->getRHS(); 2115 if (EvalResult.Val.getInt() == 0) 2116 std::swap(TrueSide, FalseSide); 2117 2118 if (TrueSide && CheckArithmeticConstantExpression(TrueSide)) 2119 return true; 2120 2121 // Okay, the evaluated side evaluates to a constant, so we accept this. 2122 // Check to see if the other side is obviously not a constant. If so, 2123 // emit a warning that this is a GNU extension. 2124 if (FalseSide && !FalseSide->isEvaluatable(Context)) 2125 Diag(Init->getExprLoc(), 2126 diag::ext_typecheck_expression_not_constant_but_accepted) 2127 << FalseSide->getSourceRange(); 2128 return false; 2129 } 2130 } 2131} 2132 2133bool Sema::CheckForConstantInitializer(Expr *Init, QualType DclT) { 2134 if (DesignatedInitExpr *DIE = dyn_cast<DesignatedInitExpr>(Init)) 2135 Init = DIE->getInit(); 2136 2137 Init = Init->IgnoreParens(); 2138 2139 if (Init->isEvaluatable(Context)) 2140 return false; 2141 2142 // Look through CXXDefaultArgExprs; they have no meaning in this context. 2143 if (CXXDefaultArgExpr* DAE = dyn_cast<CXXDefaultArgExpr>(Init)) 2144 return CheckForConstantInitializer(DAE->getExpr(), DclT); 2145 2146 if (CompoundLiteralExpr *e = dyn_cast<CompoundLiteralExpr>(Init)) 2147 return CheckForConstantInitializer(e->getInitializer(), DclT); 2148 2149 if (isa<ImplicitValueInitExpr>(Init)) { 2150 // FIXME: In C++, check for non-POD types. 2151 return false; 2152 } 2153 2154 if (InitListExpr *Exp = dyn_cast<InitListExpr>(Init)) { 2155 unsigned numInits = Exp->getNumInits(); 2156 for (unsigned i = 0; i < numInits; i++) { 2157 // FIXME: Need to get the type of the declaration for C++, 2158 // because it could be a reference? 2159 2160 if (CheckForConstantInitializer(Exp->getInit(i), 2161 Exp->getInit(i)->getType())) 2162 return true; 2163 } 2164 return false; 2165 } 2166 2167 // FIXME: We can probably remove some of this code below, now that 2168 // Expr::Evaluate is doing the heavy lifting for scalars. 2169 2170 if (Init->isNullPointerConstant(Context)) 2171 return false; 2172 if (Init->getType()->isArithmeticType()) { 2173 QualType InitTy = Context.getCanonicalType(Init->getType()) 2174 .getUnqualifiedType(); 2175 if (InitTy == Context.BoolTy) { 2176 // Special handling for pointers implicitly cast to bool; 2177 // (e.g. "_Bool rr = &rr;"). This is only legal at the top level. 2178 if (ImplicitCastExpr* ICE = dyn_cast<ImplicitCastExpr>(Init)) { 2179 Expr* SubE = ICE->getSubExpr(); 2180 if (SubE->getType()->isPointerType() || 2181 SubE->getType()->isArrayType() || 2182 SubE->getType()->isFunctionType()) { 2183 return CheckAddressConstantExpression(Init); 2184 } 2185 } 2186 } else if (InitTy->isIntegralType()) { 2187 Expr* SubE = 0; 2188 if (CastExpr* CE = dyn_cast<CastExpr>(Init)) 2189 SubE = CE->getSubExpr(); 2190 // Special check for pointer cast to int; we allow as an extension 2191 // an address constant cast to an integer if the integer 2192 // is of an appropriate width (this sort of code is apparently used 2193 // in some places). 2194 // FIXME: Add pedwarn? 2195 // FIXME: Don't allow bitfields here! Need the FieldDecl for that. 2196 if (SubE && (SubE->getType()->isPointerType() || 2197 SubE->getType()->isArrayType() || 2198 SubE->getType()->isFunctionType())) { 2199 unsigned IntWidth = Context.getTypeSize(Init->getType()); 2200 unsigned PointerWidth = Context.getTypeSize(Context.VoidPtrTy); 2201 if (IntWidth >= PointerWidth) 2202 return CheckAddressConstantExpression(Init); 2203 } 2204 } 2205 2206 return CheckArithmeticConstantExpression(Init); 2207 } 2208 2209 if (Init->getType()->isPointerType()) 2210 return CheckAddressConstantExpression(Init); 2211 2212 // An array type at the top level that isn't an init-list must 2213 // be a string literal 2214 if (Init->getType()->isArrayType()) 2215 return false; 2216 2217 if (Init->getType()->isFunctionType()) 2218 return false; 2219 2220 // Allow block exprs at top level. 2221 if (Init->getType()->isBlockPointerType()) 2222 return false; 2223 2224 // GCC cast to union extension 2225 // note: the validity of the cast expr is checked by CheckCastTypes() 2226 if (CastExpr *C = dyn_cast<CastExpr>(Init)) { 2227 QualType T = C->getType(); 2228 return T->isUnionType() && CheckForConstantInitializer(C->getSubExpr(), T); 2229 } 2230 2231 InitializerElementNotConstant(Init); 2232 return true; 2233} 2234 2235void Sema::AddInitializerToDecl(DeclTy *dcl, ExprArg init) { 2236 AddInitializerToDecl(dcl, move(init), /*DirectInit=*/false); 2237} 2238 2239/// AddInitializerToDecl - Adds the initializer Init to the 2240/// declaration dcl. If DirectInit is true, this is C++ direct 2241/// initialization rather than copy initialization. 2242void Sema::AddInitializerToDecl(DeclTy *dcl, ExprArg init, bool DirectInit) { 2243 Decl *RealDecl = static_cast<Decl *>(dcl); 2244 Expr *Init = static_cast<Expr *>(init.release()); 2245 assert(Init && "missing initializer"); 2246 2247 // If there is no declaration, there was an error parsing it. Just ignore 2248 // the initializer. 2249 if (RealDecl == 0) { 2250 delete Init; 2251 return; 2252 } 2253 2254 VarDecl *VDecl = dyn_cast<VarDecl>(RealDecl); 2255 if (!VDecl) { 2256 Diag(RealDecl->getLocation(), diag::err_illegal_initializer); 2257 RealDecl->setInvalidDecl(); 2258 return; 2259 } 2260 // Get the decls type and save a reference for later, since 2261 // CheckInitializerTypes may change it. 2262 QualType DclT = VDecl->getType(), SavT = DclT; 2263 if (VDecl->isBlockVarDecl()) { 2264 VarDecl::StorageClass SC = VDecl->getStorageClass(); 2265 if (SC == VarDecl::Extern) { // C99 6.7.8p5 2266 Diag(VDecl->getLocation(), diag::err_block_extern_cant_init); 2267 VDecl->setInvalidDecl(); 2268 } else 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 if (SC == VarDecl::Static) // C99 6.7.8p4. 2276 CheckForConstantInitializer(Init, DclT); 2277 } 2278 } 2279 } else if (VDecl->isFileVarDecl()) { 2280 if (VDecl->getStorageClass() == VarDecl::Extern) 2281 Diag(VDecl->getLocation(), diag::warn_extern_init); 2282 if (!VDecl->isInvalidDecl()) 2283 if (CheckInitializerTypes(Init, DclT, VDecl->getLocation(), 2284 VDecl->getDeclName(), DirectInit)) 2285 VDecl->setInvalidDecl(); 2286 2287 // C++ 3.6.2p2, allow dynamic initialization of static initializers. 2288 if (!getLangOptions().CPlusPlus) { 2289 // C99 6.7.8p4. All file scoped initializers need to be constant. 2290 CheckForConstantInitializer(Init, DclT); 2291 } 2292 } 2293 // If the type changed, it means we had an incomplete type that was 2294 // completed by the initializer. For example: 2295 // int ary[] = { 1, 3, 5 }; 2296 // "ary" transitions from a VariableArrayType to a ConstantArrayType. 2297 if (!VDecl->isInvalidDecl() && (DclT != SavT)) { 2298 VDecl->setType(DclT); 2299 Init->setType(DclT); 2300 } 2301 2302 // Attach the initializer to the decl. 2303 VDecl->setInit(Init); 2304 return; 2305} 2306 2307void Sema::ActOnUninitializedDecl(DeclTy *dcl) { 2308 Decl *RealDecl = static_cast<Decl *>(dcl); 2309 2310 // If there is no declaration, there was an error parsing it. Just ignore it. 2311 if (RealDecl == 0) 2312 return; 2313 2314 if (VarDecl *Var = dyn_cast<VarDecl>(RealDecl)) { 2315 QualType Type = Var->getType(); 2316 // C++ [dcl.init.ref]p3: 2317 // The initializer can be omitted for a reference only in a 2318 // parameter declaration (8.3.5), in the declaration of a 2319 // function return type, in the declaration of a class member 2320 // within its class declaration (9.2), and where the extern 2321 // specifier is explicitly used. 2322 if (Type->isReferenceType() && 2323 Var->getStorageClass() != VarDecl::Extern && 2324 Var->getStorageClass() != VarDecl::PrivateExtern) { 2325 Diag(Var->getLocation(), diag::err_reference_var_requires_init) 2326 << Var->getDeclName() 2327 << SourceRange(Var->getLocation(), Var->getLocation()); 2328 Var->setInvalidDecl(); 2329 return; 2330 } 2331 2332 // C++ [dcl.init]p9: 2333 // 2334 // If no initializer is specified for an object, and the object 2335 // is of (possibly cv-qualified) non-POD class type (or array 2336 // thereof), the object shall be default-initialized; if the 2337 // object is of const-qualified type, the underlying class type 2338 // shall have a user-declared default constructor. 2339 if (getLangOptions().CPlusPlus) { 2340 QualType InitType = Type; 2341 if (const ArrayType *Array = Context.getAsArrayType(Type)) 2342 InitType = Array->getElementType(); 2343 if (Var->getStorageClass() != VarDecl::Extern && 2344 Var->getStorageClass() != VarDecl::PrivateExtern && 2345 InitType->isRecordType()) { 2346 const CXXConstructorDecl *Constructor 2347 = PerformInitializationByConstructor(InitType, 0, 0, 2348 Var->getLocation(), 2349 SourceRange(Var->getLocation(), 2350 Var->getLocation()), 2351 Var->getDeclName(), 2352 IK_Default); 2353 if (!Constructor) 2354 Var->setInvalidDecl(); 2355 } 2356 } 2357 2358#if 0 2359 // FIXME: Temporarily disabled because we are not properly parsing 2360 // linkage specifications on declarations, e.g., 2361 // 2362 // extern "C" const CGPoint CGPointerZero; 2363 // 2364 // C++ [dcl.init]p9: 2365 // 2366 // If no initializer is specified for an object, and the 2367 // object is of (possibly cv-qualified) non-POD class type (or 2368 // array thereof), the object shall be default-initialized; if 2369 // the object is of const-qualified type, the underlying class 2370 // type shall have a user-declared default 2371 // constructor. Otherwise, if no initializer is specified for 2372 // an object, the object and its subobjects, if any, have an 2373 // indeterminate initial value; if the object or any of its 2374 // subobjects are of const-qualified type, the program is 2375 // ill-formed. 2376 // 2377 // This isn't technically an error in C, so we don't diagnose it. 2378 // 2379 // FIXME: Actually perform the POD/user-defined default 2380 // constructor check. 2381 if (getLangOptions().CPlusPlus && 2382 Context.getCanonicalType(Type).isConstQualified() && 2383 Var->getStorageClass() != VarDecl::Extern) 2384 Diag(Var->getLocation(), diag::err_const_var_requires_init) 2385 << Var->getName() 2386 << SourceRange(Var->getLocation(), Var->getLocation()); 2387#endif 2388 } 2389} 2390 2391/// The declarators are chained together backwards, reverse the list. 2392Sema::DeclTy *Sema::FinalizeDeclaratorGroup(Scope *S, DeclTy *group) { 2393 // Often we have single declarators, handle them quickly. 2394 Decl *GroupDecl = static_cast<Decl*>(group); 2395 if (GroupDecl == 0) 2396 return 0; 2397 2398 Decl *Group = dyn_cast<Decl>(GroupDecl); 2399 Decl *NewGroup = 0; 2400 if (Group->getNextDeclarator() == 0) 2401 NewGroup = Group; 2402 else { // reverse the list. 2403 while (Group) { 2404 Decl *Next = Group->getNextDeclarator(); 2405 Group->setNextDeclarator(NewGroup); 2406 NewGroup = Group; 2407 Group = Next; 2408 } 2409 } 2410 // Perform semantic analysis that depends on having fully processed both 2411 // the declarator and initializer. 2412 for (Decl *ID = NewGroup; ID; ID = ID->getNextDeclarator()) { 2413 VarDecl *IDecl = dyn_cast<VarDecl>(ID); 2414 if (!IDecl) 2415 continue; 2416 QualType T = IDecl->getType(); 2417 2418 if (T->isVariableArrayType()) { 2419 const VariableArrayType *VAT = Context.getAsVariableArrayType(T); 2420 2421 // FIXME: This won't give the correct result for 2422 // int a[10][n]; 2423 SourceRange SizeRange = VAT->getSizeExpr()->getSourceRange(); 2424 if (IDecl->isFileVarDecl()) { 2425 Diag(IDecl->getLocation(), diag::err_vla_decl_in_file_scope) << 2426 SizeRange; 2427 2428 IDecl->setInvalidDecl(); 2429 } else { 2430 // C99 6.7.5.2p2: If an identifier is declared to be an object with 2431 // static storage duration, it shall not have a variable length array. 2432 if (IDecl->getStorageClass() == VarDecl::Static) { 2433 Diag(IDecl->getLocation(), diag::err_vla_decl_has_static_storage) 2434 << SizeRange; 2435 IDecl->setInvalidDecl(); 2436 } else if (IDecl->getStorageClass() == VarDecl::Extern) { 2437 Diag(IDecl->getLocation(), diag::err_vla_decl_has_extern_linkage) 2438 << SizeRange; 2439 IDecl->setInvalidDecl(); 2440 } 2441 } 2442 } else if (T->isVariablyModifiedType()) { 2443 if (IDecl->isFileVarDecl()) { 2444 Diag(IDecl->getLocation(), diag::err_vm_decl_in_file_scope); 2445 IDecl->setInvalidDecl(); 2446 } else { 2447 if (IDecl->getStorageClass() == VarDecl::Extern) { 2448 Diag(IDecl->getLocation(), diag::err_vm_decl_has_extern_linkage); 2449 IDecl->setInvalidDecl(); 2450 } 2451 } 2452 } 2453 2454 // Block scope. C99 6.7p7: If an identifier for an object is declared with 2455 // no linkage (C99 6.2.2p6), the type for the object shall be complete... 2456 if (IDecl->isBlockVarDecl() && 2457 IDecl->getStorageClass() != VarDecl::Extern) { 2458 if (!IDecl->isInvalidDecl() && 2459 DiagnoseIncompleteType(IDecl->getLocation(), T, 2460 diag::err_typecheck_decl_incomplete_type)) 2461 IDecl->setInvalidDecl(); 2462 } 2463 // File scope. C99 6.9.2p2: A declaration of an identifier for and 2464 // object that has file scope without an initializer, and without a 2465 // storage-class specifier or with the storage-class specifier "static", 2466 // constitutes a tentative definition. Note: A tentative definition with 2467 // external linkage is valid (C99 6.2.2p5). 2468 if (isTentativeDefinition(IDecl)) { 2469 if (T->isIncompleteArrayType()) { 2470 // C99 6.9.2 (p2, p5): Implicit initialization causes an incomplete 2471 // array to be completed. Don't issue a diagnostic. 2472 } else if (!IDecl->isInvalidDecl() && 2473 DiagnoseIncompleteType(IDecl->getLocation(), T, 2474 diag::err_typecheck_decl_incomplete_type)) 2475 // C99 6.9.2p3: If the declaration of an identifier for an object is 2476 // a tentative definition and has internal linkage (C99 6.2.2p3), the 2477 // declared type shall not be an incomplete type. 2478 IDecl->setInvalidDecl(); 2479 } 2480 if (IDecl->isFileVarDecl()) 2481 CheckForFileScopedRedefinitions(S, IDecl); 2482 } 2483 return NewGroup; 2484} 2485 2486/// ActOnParamDeclarator - Called from Parser::ParseFunctionDeclarator() 2487/// to introduce parameters into function prototype scope. 2488Sema::DeclTy * 2489Sema::ActOnParamDeclarator(Scope *S, Declarator &D) { 2490 const DeclSpec &DS = D.getDeclSpec(); 2491 2492 // Verify C99 6.7.5.3p2: The only SCS allowed is 'register'. 2493 VarDecl::StorageClass StorageClass = VarDecl::None; 2494 if (DS.getStorageClassSpec() == DeclSpec::SCS_register) { 2495 StorageClass = VarDecl::Register; 2496 } else if (DS.getStorageClassSpec() != DeclSpec::SCS_unspecified) { 2497 Diag(DS.getStorageClassSpecLoc(), 2498 diag::err_invalid_storage_class_in_func_decl); 2499 D.getMutableDeclSpec().ClearStorageClassSpecs(); 2500 } 2501 if (DS.isThreadSpecified()) { 2502 Diag(DS.getThreadSpecLoc(), 2503 diag::err_invalid_storage_class_in_func_decl); 2504 D.getMutableDeclSpec().ClearStorageClassSpecs(); 2505 } 2506 2507 // Check that there are no default arguments inside the type of this 2508 // parameter (C++ only). 2509 if (getLangOptions().CPlusPlus) 2510 CheckExtraCXXDefaultArguments(D); 2511 2512 // In this context, we *do not* check D.getInvalidType(). If the declarator 2513 // type was invalid, GetTypeForDeclarator() still returns a "valid" type, 2514 // though it will not reflect the user specified type. 2515 QualType parmDeclType = GetTypeForDeclarator(D, S); 2516 2517 assert(!parmDeclType.isNull() && "GetTypeForDeclarator() returned null type"); 2518 2519 // TODO: CHECK FOR CONFLICTS, multiple decls with same name in one scope. 2520 // Can this happen for params? We already checked that they don't conflict 2521 // among each other. Here they can only shadow globals, which is ok. 2522 IdentifierInfo *II = D.getIdentifier(); 2523 if (II) { 2524 if (Decl *PrevDecl = LookupName(S, II, LookupOrdinaryName)) { 2525 if (PrevDecl->isTemplateParameter()) { 2526 // Maybe we will complain about the shadowed template parameter. 2527 DiagnoseTemplateParameterShadow(D.getIdentifierLoc(), PrevDecl); 2528 // Just pretend that we didn't see the previous declaration. 2529 PrevDecl = 0; 2530 } else if (S->isDeclScope(PrevDecl)) { 2531 Diag(D.getIdentifierLoc(), diag::err_param_redefinition) << II; 2532 2533 // Recover by removing the name 2534 II = 0; 2535 D.SetIdentifier(0, D.getIdentifierLoc()); 2536 } 2537 } 2538 } 2539 2540 // Perform the default function/array conversion (C99 6.7.5.3p[7,8]). 2541 // Doing the promotion here has a win and a loss. The win is the type for 2542 // both Decl's and DeclRefExpr's will match (a convenient invariant for the 2543 // code generator). The loss is the orginal type isn't preserved. For example: 2544 // 2545 // void func(int parmvardecl[5]) { // convert "int [5]" to "int *" 2546 // int blockvardecl[5]; 2547 // sizeof(parmvardecl); // size == 4 2548 // sizeof(blockvardecl); // size == 20 2549 // } 2550 // 2551 // For expressions, all implicit conversions are captured using the 2552 // ImplicitCastExpr AST node (we have no such mechanism for Decl's). 2553 // 2554 // FIXME: If a source translation tool needs to see the original type, then 2555 // we need to consider storing both types (in ParmVarDecl)... 2556 // 2557 if (parmDeclType->isArrayType()) { 2558 // int x[restrict 4] -> int *restrict 2559 parmDeclType = Context.getArrayDecayedType(parmDeclType); 2560 } else if (parmDeclType->isFunctionType()) 2561 parmDeclType = Context.getPointerType(parmDeclType); 2562 2563 ParmVarDecl *New = ParmVarDecl::Create(Context, CurContext, 2564 D.getIdentifierLoc(), II, 2565 parmDeclType, StorageClass, 2566 0); 2567 2568 if (D.getInvalidType()) 2569 New->setInvalidDecl(); 2570 2571 // Parameter declarators cannot be qualified (C++ [dcl.meaning]p1). 2572 if (D.getCXXScopeSpec().isSet()) { 2573 Diag(D.getIdentifierLoc(), diag::err_qualified_param_declarator) 2574 << D.getCXXScopeSpec().getRange(); 2575 New->setInvalidDecl(); 2576 } 2577 2578 // Add the parameter declaration into this scope. 2579 S->AddDecl(New); 2580 if (II) 2581 IdResolver.AddDecl(New); 2582 2583 ProcessDeclAttributes(New, D); 2584 return New; 2585 2586} 2587 2588void Sema::ActOnFinishKNRParamDeclarations(Scope *S, Declarator &D) { 2589 assert(D.getTypeObject(0).Kind == DeclaratorChunk::Function && 2590 "Not a function declarator!"); 2591 DeclaratorChunk::FunctionTypeInfo &FTI = D.getTypeObject(0).Fun; 2592 2593 // Verify 6.9.1p6: 'every identifier in the identifier list shall be declared' 2594 // for a K&R function. 2595 if (!FTI.hasPrototype) { 2596 for (unsigned i = 0, e = FTI.NumArgs; i != e; ++i) { 2597 if (FTI.ArgInfo[i].Param == 0) { 2598 Diag(FTI.ArgInfo[i].IdentLoc, diag::ext_param_not_declared) 2599 << FTI.ArgInfo[i].Ident; 2600 // Implicitly declare the argument as type 'int' for lack of a better 2601 // type. 2602 DeclSpec DS; 2603 const char* PrevSpec; // unused 2604 DS.SetTypeSpecType(DeclSpec::TST_int, FTI.ArgInfo[i].IdentLoc, 2605 PrevSpec); 2606 Declarator ParamD(DS, Declarator::KNRTypeListContext); 2607 ParamD.SetIdentifier(FTI.ArgInfo[i].Ident, FTI.ArgInfo[i].IdentLoc); 2608 FTI.ArgInfo[i].Param = ActOnParamDeclarator(S, ParamD); 2609 } 2610 } 2611 } 2612} 2613 2614Sema::DeclTy *Sema::ActOnStartOfFunctionDef(Scope *FnBodyScope, Declarator &D) { 2615 assert(getCurFunctionDecl() == 0 && "Function parsing confused"); 2616 assert(D.getTypeObject(0).Kind == DeclaratorChunk::Function && 2617 "Not a function declarator!"); 2618 DeclaratorChunk::FunctionTypeInfo &FTI = D.getTypeObject(0).Fun; 2619 2620 if (FTI.hasPrototype) { 2621 // FIXME: Diagnose arguments without names in C. 2622 } 2623 2624 Scope *ParentScope = FnBodyScope->getParent(); 2625 2626 return ActOnStartOfFunctionDef(FnBodyScope, 2627 ActOnDeclarator(ParentScope, D, 0, 2628 /*IsFunctionDefinition=*/true)); 2629} 2630 2631Sema::DeclTy *Sema::ActOnStartOfFunctionDef(Scope *FnBodyScope, DeclTy *D) { 2632 Decl *decl = static_cast<Decl*>(D); 2633 FunctionDecl *FD = cast<FunctionDecl>(decl); 2634 2635 // See if this is a redefinition. 2636 const FunctionDecl *Definition; 2637 if (FD->getBody(Definition)) { 2638 Diag(FD->getLocation(), diag::err_redefinition) << FD->getDeclName(); 2639 Diag(Definition->getLocation(), diag::note_previous_definition); 2640 } 2641 2642 PushDeclContext(FnBodyScope, FD); 2643 2644 // Check the validity of our function parameters 2645 CheckParmsForFunctionDef(FD); 2646 2647 // Introduce our parameters into the function scope 2648 for (unsigned p = 0, NumParams = FD->getNumParams(); p < NumParams; ++p) { 2649 ParmVarDecl *Param = FD->getParamDecl(p); 2650 Param->setOwningFunction(FD); 2651 2652 // If this has an identifier, add it to the scope stack. 2653 if (Param->getIdentifier()) 2654 PushOnScopeChains(Param, FnBodyScope); 2655 } 2656 2657 // Checking attributes of current function definition 2658 // dllimport attribute. 2659 if (FD->getAttr<DLLImportAttr>() && (!FD->getAttr<DLLExportAttr>())) { 2660 // dllimport attribute cannot be applied to definition. 2661 if (!(FD->getAttr<DLLImportAttr>())->isInherited()) { 2662 Diag(FD->getLocation(), 2663 diag::err_attribute_can_be_applied_only_to_symbol_declaration) 2664 << "dllimport"; 2665 FD->setInvalidDecl(); 2666 return FD; 2667 } else { 2668 // If a symbol previously declared dllimport is later defined, the 2669 // attribute is ignored in subsequent references, and a warning is 2670 // emitted. 2671 Diag(FD->getLocation(), 2672 diag::warn_redeclaration_without_attribute_prev_attribute_ignored) 2673 << FD->getNameAsCString() << "dllimport"; 2674 } 2675 } 2676 return FD; 2677} 2678 2679Sema::DeclTy *Sema::ActOnFinishFunctionBody(DeclTy *D, StmtArg BodyArg) { 2680 Decl *dcl = static_cast<Decl *>(D); 2681 Stmt *Body = static_cast<Stmt*>(BodyArg.release()); 2682 if (FunctionDecl *FD = dyn_cast_or_null<FunctionDecl>(dcl)) { 2683 FD->setBody(Body); 2684 assert(FD == getCurFunctionDecl() && "Function parsing confused"); 2685 } else if (ObjCMethodDecl *MD = dyn_cast_or_null<ObjCMethodDecl>(dcl)) { 2686 MD->setBody((Stmt*)Body); 2687 } else 2688 return 0; 2689 PopDeclContext(); 2690 // Verify and clean out per-function state. 2691 2692 // Check goto/label use. 2693 for (llvm::DenseMap<IdentifierInfo*, LabelStmt*>::iterator 2694 I = LabelMap.begin(), E = LabelMap.end(); I != E; ++I) { 2695 // Verify that we have no forward references left. If so, there was a goto 2696 // or address of a label taken, but no definition of it. Label fwd 2697 // definitions are indicated with a null substmt. 2698 if (I->second->getSubStmt() == 0) { 2699 LabelStmt *L = I->second; 2700 // Emit error. 2701 Diag(L->getIdentLoc(), diag::err_undeclared_label_use) << L->getName(); 2702 2703 // At this point, we have gotos that use the bogus label. Stitch it into 2704 // the function body so that they aren't leaked and that the AST is well 2705 // formed. 2706 if (Body) { 2707 L->setSubStmt(new NullStmt(L->getIdentLoc())); 2708 cast<CompoundStmt>(Body)->push_back(L); 2709 } else { 2710 // The whole function wasn't parsed correctly, just delete this. 2711 delete L; 2712 } 2713 } 2714 } 2715 LabelMap.clear(); 2716 2717 return D; 2718} 2719 2720/// ImplicitlyDefineFunction - An undeclared identifier was used in a function 2721/// call, forming a call to an implicitly defined function (per C99 6.5.1p2). 2722NamedDecl *Sema::ImplicitlyDefineFunction(SourceLocation Loc, 2723 IdentifierInfo &II, Scope *S) { 2724 // Extension in C99. Legal in C90, but warn about it. 2725 if (getLangOptions().C99) 2726 Diag(Loc, diag::ext_implicit_function_decl) << &II; 2727 else 2728 Diag(Loc, diag::warn_implicit_function_decl) << &II; 2729 2730 // FIXME: handle stuff like: 2731 // void foo() { extern float X(); } 2732 // void bar() { X(); } <-- implicit decl for X in another scope. 2733 2734 // Set a Declarator for the implicit definition: int foo(); 2735 const char *Dummy; 2736 DeclSpec DS; 2737 bool Error = DS.SetTypeSpecType(DeclSpec::TST_int, Loc, Dummy); 2738 Error = Error; // Silence warning. 2739 assert(!Error && "Error setting up implicit decl!"); 2740 Declarator D(DS, Declarator::BlockContext); 2741 D.AddTypeInfo(DeclaratorChunk::getFunction(false, false, 0, 0, 0, Loc, D)); 2742 D.SetIdentifier(&II, Loc); 2743 2744 // Insert this function into translation-unit scope. 2745 2746 DeclContext *PrevDC = CurContext; 2747 CurContext = Context.getTranslationUnitDecl(); 2748 2749 FunctionDecl *FD = 2750 dyn_cast<FunctionDecl>(static_cast<Decl*>(ActOnDeclarator(TUScope, D, 0))); 2751 FD->setImplicit(); 2752 2753 CurContext = PrevDC; 2754 2755 return FD; 2756} 2757 2758 2759TypedefDecl *Sema::ParseTypedefDecl(Scope *S, Declarator &D, QualType T, 2760 Decl *LastDeclarator) { 2761 assert(D.getIdentifier() && "Wrong callback for declspec without declarator"); 2762 assert(!T.isNull() && "GetTypeForDeclarator() returned null type"); 2763 2764 // Scope manipulation handled by caller. 2765 TypedefDecl *NewTD = TypedefDecl::Create(Context, CurContext, 2766 D.getIdentifierLoc(), 2767 D.getIdentifier(), 2768 T); 2769 NewTD->setNextDeclarator(LastDeclarator); 2770 if (D.getInvalidType()) 2771 NewTD->setInvalidDecl(); 2772 return NewTD; 2773} 2774 2775/// ActOnTag - This is invoked when we see 'struct foo' or 'struct {'. In the 2776/// former case, Name will be non-null. In the later case, Name will be null. 2777/// TagSpec indicates what kind of tag this is. TK indicates whether this is a 2778/// reference/declaration/definition of a tag. 2779Sema::DeclTy *Sema::ActOnTag(Scope *S, unsigned TagSpec, TagKind TK, 2780 SourceLocation KWLoc, const CXXScopeSpec &SS, 2781 IdentifierInfo *Name, SourceLocation NameLoc, 2782 AttributeList *Attr, 2783 MultiTemplateParamsArg TemplateParameterLists) { 2784 // If this is not a definition, it must have a name. 2785 assert((Name != 0 || TK == TK_Definition) && 2786 "Nameless record must be a definition!"); 2787 2788 TagDecl::TagKind Kind; 2789 switch (TagSpec) { 2790 default: assert(0 && "Unknown tag type!"); 2791 case DeclSpec::TST_struct: Kind = TagDecl::TK_struct; break; 2792 case DeclSpec::TST_union: Kind = TagDecl::TK_union; break; 2793 case DeclSpec::TST_class: Kind = TagDecl::TK_class; break; 2794 case DeclSpec::TST_enum: Kind = TagDecl::TK_enum; break; 2795 } 2796 2797 DeclContext *SearchDC = CurContext; 2798 DeclContext *DC = CurContext; 2799 Decl *PrevDecl = 0; 2800 2801 bool Invalid = false; 2802 2803 if (Name && SS.isNotEmpty()) { 2804 // We have a nested-name tag ('struct foo::bar'). 2805 2806 // Check for invalid 'foo::'. 2807 if (SS.isInvalid()) { 2808 Name = 0; 2809 goto CreateNewDecl; 2810 } 2811 2812 DC = static_cast<DeclContext*>(SS.getScopeRep()); 2813 SearchDC = DC; 2814 // Look-up name inside 'foo::'. 2815 PrevDecl = dyn_cast_or_null<TagDecl>( 2816 LookupQualifiedName(DC, Name, LookupTagName).getAsDecl()); 2817 2818 // A tag 'foo::bar' must already exist. 2819 if (PrevDecl == 0) { 2820 Diag(NameLoc, diag::err_not_tag_in_scope) << Name << SS.getRange(); 2821 Name = 0; 2822 goto CreateNewDecl; 2823 } 2824 } else if (Name) { 2825 // If this is a named struct, check to see if there was a previous forward 2826 // declaration or definition. 2827 Decl *D = LookupName(S, Name, LookupTagName); 2828 PrevDecl = dyn_cast_or_null<NamedDecl>(D); 2829 2830 if (!getLangOptions().CPlusPlus && TK != TK_Reference) { 2831 // FIXME: This makes sure that we ignore the contexts associated 2832 // with C structs, unions, and enums when looking for a matching 2833 // tag declaration or definition. See the similar lookup tweak 2834 // in Sema::LookupName; is there a better way to deal with this? 2835 while (isa<RecordDecl>(SearchDC) || isa<EnumDecl>(SearchDC)) 2836 SearchDC = SearchDC->getParent(); 2837 } 2838 } 2839 2840 if (PrevDecl && PrevDecl->isTemplateParameter()) { 2841 // Maybe we will complain about the shadowed template parameter. 2842 DiagnoseTemplateParameterShadow(NameLoc, PrevDecl); 2843 // Just pretend that we didn't see the previous declaration. 2844 PrevDecl = 0; 2845 } 2846 2847 if (PrevDecl) { 2848 if (TagDecl *PrevTagDecl = dyn_cast<TagDecl>(PrevDecl)) { 2849 // If this is a use of a previous tag, or if the tag is already declared 2850 // in the same scope (so that the definition/declaration completes or 2851 // rementions the tag), reuse the decl. 2852 if (TK == TK_Reference || isDeclInScope(PrevDecl, SearchDC, S)) { 2853 // Make sure that this wasn't declared as an enum and now used as a 2854 // struct or something similar. 2855 if (PrevTagDecl->getTagKind() != Kind) { 2856 Diag(KWLoc, diag::err_use_with_wrong_tag) << Name; 2857 Diag(PrevDecl->getLocation(), diag::note_previous_use); 2858 // Recover by making this an anonymous redefinition. 2859 Name = 0; 2860 PrevDecl = 0; 2861 Invalid = true; 2862 } else { 2863 // If this is a use, just return the declaration we found. 2864 2865 // FIXME: In the future, return a variant or some other clue 2866 // for the consumer of this Decl to know it doesn't own it. 2867 // For our current ASTs this shouldn't be a problem, but will 2868 // need to be changed with DeclGroups. 2869 if (TK == TK_Reference) 2870 return PrevDecl; 2871 2872 // Diagnose attempts to redefine a tag. 2873 if (TK == TK_Definition) { 2874 if (TagDecl *Def = PrevTagDecl->getDefinition(Context)) { 2875 Diag(NameLoc, diag::err_redefinition) << Name; 2876 Diag(Def->getLocation(), diag::note_previous_definition); 2877 // If this is a redefinition, recover by making this 2878 // struct be anonymous, which will make any later 2879 // references get the previous definition. 2880 Name = 0; 2881 PrevDecl = 0; 2882 Invalid = true; 2883 } else { 2884 // If the type is currently being defined, complain 2885 // about a nested redefinition. 2886 TagType *Tag = cast<TagType>(Context.getTagDeclType(PrevTagDecl)); 2887 if (Tag->isBeingDefined()) { 2888 Diag(NameLoc, diag::err_nested_redefinition) << Name; 2889 Diag(PrevTagDecl->getLocation(), 2890 diag::note_previous_definition); 2891 Name = 0; 2892 PrevDecl = 0; 2893 Invalid = true; 2894 } 2895 } 2896 2897 // Okay, this is definition of a previously declared or referenced 2898 // tag PrevDecl. We're going to create a new Decl for it. 2899 } 2900 } 2901 // If we get here we have (another) forward declaration or we 2902 // have a definition. Just create a new decl. 2903 } else { 2904 // If we get here, this is a definition of a new tag type in a nested 2905 // scope, e.g. "struct foo; void bar() { struct foo; }", just create a 2906 // new decl/type. We set PrevDecl to NULL so that the entities 2907 // have distinct types. 2908 PrevDecl = 0; 2909 } 2910 // If we get here, we're going to create a new Decl. If PrevDecl 2911 // is non-NULL, it's a definition of the tag declared by 2912 // PrevDecl. If it's NULL, we have a new definition. 2913 } else { 2914 // PrevDecl is a namespace, template, or anything else 2915 // that lives in the IDNS_Tag identifier namespace. 2916 if (isDeclInScope(PrevDecl, SearchDC, S)) { 2917 // The tag name clashes with a namespace name, issue an error and 2918 // recover by making this tag be anonymous. 2919 Diag(NameLoc, diag::err_redefinition_different_kind) << Name; 2920 Diag(PrevDecl->getLocation(), diag::note_previous_definition); 2921 Name = 0; 2922 PrevDecl = 0; 2923 Invalid = true; 2924 } else { 2925 // The existing declaration isn't relevant to us; we're in a 2926 // new scope, so clear out the previous declaration. 2927 PrevDecl = 0; 2928 } 2929 } 2930 } else if (TK == TK_Reference && SS.isEmpty() && Name && 2931 (Kind != TagDecl::TK_enum)) { 2932 // C++ [basic.scope.pdecl]p5: 2933 // -- for an elaborated-type-specifier of the form 2934 // 2935 // class-key identifier 2936 // 2937 // if the elaborated-type-specifier is used in the 2938 // decl-specifier-seq or parameter-declaration-clause of a 2939 // function defined in namespace scope, the identifier is 2940 // declared as a class-name in the namespace that contains 2941 // the declaration; otherwise, except as a friend 2942 // declaration, the identifier is declared in the smallest 2943 // non-class, non-function-prototype scope that contains the 2944 // declaration. 2945 // 2946 // C99 6.7.2.3p8 has a similar (but not identical!) provision for 2947 // C structs and unions. 2948 2949 // Find the context where we'll be declaring the tag. 2950 // FIXME: We would like to maintain the current DeclContext as the 2951 // lexical context, 2952 while (SearchDC->isRecord()) 2953 SearchDC = SearchDC->getParent(); 2954 2955 // Find the scope where we'll be declaring the tag. 2956 while (S->isClassScope() || 2957 (getLangOptions().CPlusPlus && S->isFunctionPrototypeScope()) || 2958 ((S->getFlags() & Scope::DeclScope) == 0) || 2959 (S->getEntity() && 2960 ((DeclContext *)S->getEntity())->isTransparentContext())) 2961 S = S->getParent(); 2962 } 2963 2964CreateNewDecl: 2965 2966 // If there is an identifier, use the location of the identifier as the 2967 // location of the decl, otherwise use the location of the struct/union 2968 // keyword. 2969 SourceLocation Loc = NameLoc.isValid() ? NameLoc : KWLoc; 2970 2971 // Otherwise, create a new declaration. If there is a previous 2972 // declaration of the same entity, the two will be linked via 2973 // PrevDecl. 2974 TagDecl *New; 2975 2976 if (Kind == TagDecl::TK_enum) { 2977 // FIXME: Tag decls should be chained to any simultaneous vardecls, e.g.: 2978 // enum X { A, B, C } D; D should chain to X. 2979 New = EnumDecl::Create(Context, SearchDC, Loc, Name, 2980 cast_or_null<EnumDecl>(PrevDecl)); 2981 // If this is an undefined enum, warn. 2982 if (TK != TK_Definition) Diag(Loc, diag::ext_forward_ref_enum); 2983 } else { 2984 // struct/union/class 2985 2986 // FIXME: Tag decls should be chained to any simultaneous vardecls, e.g.: 2987 // struct X { int A; } D; D should chain to X. 2988 if (getLangOptions().CPlusPlus) 2989 // FIXME: Look for a way to use RecordDecl for simple structs. 2990 New = CXXRecordDecl::Create(Context, Kind, SearchDC, Loc, Name, 2991 cast_or_null<CXXRecordDecl>(PrevDecl)); 2992 else 2993 New = RecordDecl::Create(Context, Kind, SearchDC, Loc, Name, 2994 cast_or_null<RecordDecl>(PrevDecl)); 2995 } 2996 2997 if (Kind != TagDecl::TK_enum) { 2998 // Handle #pragma pack: if the #pragma pack stack has non-default 2999 // alignment, make up a packed attribute for this decl. These 3000 // attributes are checked when the ASTContext lays out the 3001 // structure. 3002 // 3003 // It is important for implementing the correct semantics that this 3004 // happen here (in act on tag decl). The #pragma pack stack is 3005 // maintained as a result of parser callbacks which can occur at 3006 // many points during the parsing of a struct declaration (because 3007 // the #pragma tokens are effectively skipped over during the 3008 // parsing of the struct). 3009 if (unsigned Alignment = PackContext.getAlignment()) 3010 New->addAttr(new PackedAttr(Alignment * 8)); 3011 } 3012 3013 if (getLangOptions().CPlusPlus && SS.isEmpty() && Name && !Invalid) { 3014 // C++ [dcl.typedef]p3: 3015 // [...] Similarly, in a given scope, a class or enumeration 3016 // shall not be declared with the same name as a typedef-name 3017 // that is declared in that scope and refers to a type other 3018 // than the class or enumeration itself. 3019 LookupResult Lookup = LookupName(S, Name, LookupOrdinaryName, true); 3020 TypedefDecl *PrevTypedef = 0; 3021 if (Lookup.getKind() == LookupResult::Found) 3022 PrevTypedef = dyn_cast<TypedefDecl>(Lookup.getAsDecl()); 3023 3024 if (PrevTypedef && isDeclInScope(PrevTypedef, SearchDC, S) && 3025 Context.getCanonicalType(Context.getTypeDeclType(PrevTypedef)) != 3026 Context.getCanonicalType(Context.getTypeDeclType(New))) { 3027 Diag(Loc, diag::err_tag_definition_of_typedef) 3028 << Context.getTypeDeclType(New) 3029 << PrevTypedef->getUnderlyingType(); 3030 Diag(PrevTypedef->getLocation(), diag::note_previous_definition); 3031 Invalid = true; 3032 } 3033 } 3034 3035 if (Invalid) 3036 New->setInvalidDecl(); 3037 3038 if (Attr) 3039 ProcessDeclAttributeList(New, Attr); 3040 3041 // If we're declaring or defining a tag in function prototype scope 3042 // in C, note that this type can only be used within the function. 3043 if (Name && S->isFunctionPrototypeScope() && !getLangOptions().CPlusPlus) 3044 Diag(Loc, diag::warn_decl_in_param_list) << Context.getTagDeclType(New); 3045 3046 // Set the lexical context. If the tag has a C++ scope specifier, the 3047 // lexical context will be different from the semantic context. 3048 New->setLexicalDeclContext(CurContext); 3049 3050 if (TK == TK_Definition) 3051 New->startDefinition(); 3052 3053 // If this has an identifier, add it to the scope stack. 3054 if (Name) { 3055 S = getNonFieldDeclScope(S); 3056 PushOnScopeChains(New, S); 3057 } else { 3058 CurContext->addDecl(New); 3059 } 3060 3061 return New; 3062} 3063 3064void Sema::ActOnTagStartDefinition(Scope *S, DeclTy *TagD) { 3065 TagDecl *Tag = cast<TagDecl>((Decl *)TagD); 3066 3067 // Enter the tag context. 3068 PushDeclContext(S, Tag); 3069 3070 if (CXXRecordDecl *Record = dyn_cast<CXXRecordDecl>(Tag)) { 3071 FieldCollector->StartClass(); 3072 3073 if (Record->getIdentifier()) { 3074 // C++ [class]p2: 3075 // [...] The class-name is also inserted into the scope of the 3076 // class itself; this is known as the injected-class-name. For 3077 // purposes of access checking, the injected-class-name is treated 3078 // as if it were a public member name. 3079 RecordDecl *InjectedClassName 3080 = CXXRecordDecl::Create(Context, Record->getTagKind(), 3081 CurContext, Record->getLocation(), 3082 Record->getIdentifier(), Record); 3083 InjectedClassName->setImplicit(); 3084 PushOnScopeChains(InjectedClassName, S); 3085 } 3086 } 3087} 3088 3089void Sema::ActOnTagFinishDefinition(Scope *S, DeclTy *TagD) { 3090 TagDecl *Tag = cast<TagDecl>((Decl *)TagD); 3091 3092 if (isa<CXXRecordDecl>(Tag)) 3093 FieldCollector->FinishClass(); 3094 3095 // Exit this scope of this tag's definition. 3096 PopDeclContext(); 3097 3098 // Notify the consumer that we've defined a tag. 3099 Consumer.HandleTagDeclDefinition(Tag); 3100} 3101 3102/// TryToFixInvalidVariablyModifiedType - Helper method to turn variable array 3103/// types into constant array types in certain situations which would otherwise 3104/// be errors (for GCC compatibility). 3105static QualType TryToFixInvalidVariablyModifiedType(QualType T, 3106 ASTContext &Context) { 3107 // This method tries to turn a variable array into a constant 3108 // array even when the size isn't an ICE. This is necessary 3109 // for compatibility with code that depends on gcc's buggy 3110 // constant expression folding, like struct {char x[(int)(char*)2];} 3111 const VariableArrayType* VLATy = dyn_cast<VariableArrayType>(T); 3112 if (!VLATy) return QualType(); 3113 3114 Expr::EvalResult EvalResult; 3115 if (!VLATy->getSizeExpr() || 3116 !VLATy->getSizeExpr()->Evaluate(EvalResult, Context)) 3117 return QualType(); 3118 3119 assert(EvalResult.Val.isInt() && "Size expressions must be integers!"); 3120 llvm::APSInt &Res = EvalResult.Val.getInt(); 3121 if (Res >= llvm::APSInt(Res.getBitWidth(), Res.isUnsigned())) 3122 return Context.getConstantArrayType(VLATy->getElementType(), 3123 Res, ArrayType::Normal, 0); 3124 return QualType(); 3125} 3126 3127bool Sema::VerifyBitField(SourceLocation FieldLoc, IdentifierInfo *FieldName, 3128 QualType FieldTy, const Expr *BitWidth) { 3129 // FIXME: 6.7.2.1p4 - verify the field type. 3130 3131 llvm::APSInt Value; 3132 if (VerifyIntegerConstantExpression(BitWidth, &Value)) 3133 return true; 3134 3135 // Zero-width bitfield is ok for anonymous field. 3136 if (Value == 0 && FieldName) 3137 return Diag(FieldLoc, diag::err_bitfield_has_zero_width) << FieldName; 3138 3139 if (Value.isNegative()) 3140 return Diag(FieldLoc, diag::err_bitfield_has_negative_width) << FieldName; 3141 3142 uint64_t TypeSize = Context.getTypeSize(FieldTy); 3143 // FIXME: We won't need the 0 size once we check that the field type is valid. 3144 if (TypeSize && Value.getZExtValue() > TypeSize) 3145 return Diag(FieldLoc, diag::err_bitfield_width_exceeds_type_size) 3146 << FieldName << (unsigned)TypeSize; 3147 3148 return false; 3149} 3150 3151/// ActOnField - Each field of a struct/union/class is passed into this in order 3152/// to create a FieldDecl object for it. 3153Sema::DeclTy *Sema::ActOnField(Scope *S, DeclTy *TagD, 3154 SourceLocation DeclStart, 3155 Declarator &D, ExprTy *BitfieldWidth) { 3156 IdentifierInfo *II = D.getIdentifier(); 3157 Expr *BitWidth = (Expr*)BitfieldWidth; 3158 SourceLocation Loc = DeclStart; 3159 RecordDecl *Record = (RecordDecl *)TagD; 3160 if (II) Loc = D.getIdentifierLoc(); 3161 3162 // FIXME: Unnamed fields can be handled in various different ways, for 3163 // example, unnamed unions inject all members into the struct namespace! 3164 3165 QualType T = GetTypeForDeclarator(D, S); 3166 assert(!T.isNull() && "GetTypeForDeclarator() returned null type"); 3167 bool InvalidDecl = false; 3168 3169 // C99 6.7.2.1p8: A member of a structure or union may have any type other 3170 // than a variably modified type. 3171 if (T->isVariablyModifiedType()) { 3172 QualType FixedTy = TryToFixInvalidVariablyModifiedType(T, Context); 3173 if (!FixedTy.isNull()) { 3174 Diag(Loc, diag::warn_illegal_constant_array_size); 3175 T = FixedTy; 3176 } else { 3177 Diag(Loc, diag::err_typecheck_field_variable_size); 3178 T = Context.IntTy; 3179 InvalidDecl = true; 3180 } 3181 } 3182 3183 if (BitWidth) { 3184 if (VerifyBitField(Loc, II, T, BitWidth)) 3185 InvalidDecl = true; 3186 } else { 3187 // Not a bitfield. 3188 3189 // validate II. 3190 3191 } 3192 3193 // FIXME: Chain fielddecls together. 3194 FieldDecl *NewFD; 3195 3196 NewFD = FieldDecl::Create(Context, Record, 3197 Loc, II, T, BitWidth, 3198 D.getDeclSpec().getStorageClassSpec() == 3199 DeclSpec::SCS_mutable); 3200 3201 if (II) { 3202 Decl *PrevDecl = LookupName(S, II, LookupMemberName, true); 3203 if (PrevDecl && isDeclInScope(PrevDecl, CurContext, S) 3204 && !isa<TagDecl>(PrevDecl)) { 3205 Diag(Loc, diag::err_duplicate_member) << II; 3206 Diag(PrevDecl->getLocation(), diag::note_previous_declaration); 3207 NewFD->setInvalidDecl(); 3208 Record->setInvalidDecl(); 3209 } 3210 } 3211 3212 if (getLangOptions().CPlusPlus) { 3213 CheckExtraCXXDefaultArguments(D); 3214 if (!T->isPODType()) 3215 cast<CXXRecordDecl>(Record)->setPOD(false); 3216 } 3217 3218 ProcessDeclAttributes(NewFD, D); 3219 3220 if (D.getInvalidType() || InvalidDecl) 3221 NewFD->setInvalidDecl(); 3222 3223 if (II) { 3224 PushOnScopeChains(NewFD, S); 3225 } else 3226 Record->addDecl(NewFD); 3227 3228 return NewFD; 3229} 3230 3231/// TranslateIvarVisibility - Translate visibility from a token ID to an 3232/// AST enum value. 3233static ObjCIvarDecl::AccessControl 3234TranslateIvarVisibility(tok::ObjCKeywordKind ivarVisibility) { 3235 switch (ivarVisibility) { 3236 default: assert(0 && "Unknown visitibility kind"); 3237 case tok::objc_private: return ObjCIvarDecl::Private; 3238 case tok::objc_public: return ObjCIvarDecl::Public; 3239 case tok::objc_protected: return ObjCIvarDecl::Protected; 3240 case tok::objc_package: return ObjCIvarDecl::Package; 3241 } 3242} 3243 3244/// ActOnIvar - Each ivar field of an objective-c class is passed into this 3245/// in order to create an IvarDecl object for it. 3246Sema::DeclTy *Sema::ActOnIvar(Scope *S, 3247 SourceLocation DeclStart, 3248 Declarator &D, ExprTy *BitfieldWidth, 3249 tok::ObjCKeywordKind Visibility) { 3250 3251 IdentifierInfo *II = D.getIdentifier(); 3252 Expr *BitWidth = (Expr*)BitfieldWidth; 3253 SourceLocation Loc = DeclStart; 3254 if (II) Loc = D.getIdentifierLoc(); 3255 3256 // FIXME: Unnamed fields can be handled in various different ways, for 3257 // example, unnamed unions inject all members into the struct namespace! 3258 3259 QualType T = GetTypeForDeclarator(D, S); 3260 assert(!T.isNull() && "GetTypeForDeclarator() returned null type"); 3261 bool InvalidDecl = false; 3262 3263 if (BitWidth) { 3264 // TODO: Validate. 3265 //printf("WARNING: BITFIELDS IGNORED!\n"); 3266 3267 // 6.7.2.1p3 3268 // 6.7.2.1p4 3269 3270 } else { 3271 // Not a bitfield. 3272 3273 // validate II. 3274 3275 } 3276 3277 // C99 6.7.2.1p8: A member of a structure or union may have any type other 3278 // than a variably modified type. 3279 if (T->isVariablyModifiedType()) { 3280 Diag(Loc, diag::err_typecheck_ivar_variable_size); 3281 InvalidDecl = true; 3282 } 3283 3284 // Get the visibility (access control) for this ivar. 3285 ObjCIvarDecl::AccessControl ac = 3286 Visibility != tok::objc_not_keyword ? TranslateIvarVisibility(Visibility) 3287 : ObjCIvarDecl::None; 3288 3289 // Construct the decl. 3290 ObjCIvarDecl *NewID = ObjCIvarDecl::Create(Context, Loc, II, T, ac, 3291 (Expr *)BitfieldWidth); 3292 3293 if (II) { 3294 Decl *PrevDecl = LookupName(S, II, LookupMemberName, true); 3295 if (PrevDecl && isDeclInScope(PrevDecl, CurContext, S) 3296 && !isa<TagDecl>(PrevDecl)) { 3297 Diag(Loc, diag::err_duplicate_member) << II; 3298 Diag(PrevDecl->getLocation(), diag::note_previous_declaration); 3299 NewID->setInvalidDecl(); 3300 } 3301 } 3302 3303 // Process attributes attached to the ivar. 3304 ProcessDeclAttributes(NewID, D); 3305 3306 if (D.getInvalidType() || InvalidDecl) 3307 NewID->setInvalidDecl(); 3308 3309 if (II) { 3310 // FIXME: When interfaces are DeclContexts, we'll need to add 3311 // these to the interface. 3312 S->AddDecl(NewID); 3313 IdResolver.AddDecl(NewID); 3314 } 3315 3316 return NewID; 3317} 3318 3319void Sema::ActOnFields(Scope* S, 3320 SourceLocation RecLoc, DeclTy *RecDecl, 3321 DeclTy **Fields, unsigned NumFields, 3322 SourceLocation LBrac, SourceLocation RBrac, 3323 AttributeList *Attr) { 3324 Decl *EnclosingDecl = static_cast<Decl*>(RecDecl); 3325 assert(EnclosingDecl && "missing record or interface decl"); 3326 RecordDecl *Record = dyn_cast<RecordDecl>(EnclosingDecl); 3327 3328 // Verify that all the fields are okay. 3329 unsigned NumNamedMembers = 0; 3330 llvm::SmallVector<FieldDecl*, 32> RecFields; 3331 3332 for (unsigned i = 0; i != NumFields; ++i) { 3333 FieldDecl *FD = cast_or_null<FieldDecl>(static_cast<Decl*>(Fields[i])); 3334 assert(FD && "missing field decl"); 3335 3336 // Get the type for the field. 3337 Type *FDTy = FD->getType().getTypePtr(); 3338 3339 if (!FD->isAnonymousStructOrUnion()) { 3340 // Remember all fields written by the user. 3341 RecFields.push_back(FD); 3342 } 3343 3344 // C99 6.7.2.1p2 - A field may not be a function type. 3345 if (FDTy->isFunctionType()) { 3346 Diag(FD->getLocation(), diag::err_field_declared_as_function) 3347 << FD->getDeclName(); 3348 FD->setInvalidDecl(); 3349 EnclosingDecl->setInvalidDecl(); 3350 continue; 3351 } 3352 // C99 6.7.2.1p2 - A field may not be an incomplete type except... 3353 if (FDTy->isIncompleteType()) { 3354 if (!Record) { // Incomplete ivar type is always an error. 3355 DiagnoseIncompleteType(FD->getLocation(), FD->getType(), 3356 diag::err_field_incomplete); 3357 FD->setInvalidDecl(); 3358 EnclosingDecl->setInvalidDecl(); 3359 continue; 3360 } 3361 if (i != NumFields-1 || // ... that the last member ... 3362 !Record->isStruct() || // ... of a structure ... 3363 !FDTy->isArrayType()) { //... may have incomplete array type. 3364 DiagnoseIncompleteType(FD->getLocation(), FD->getType(), 3365 diag::err_field_incomplete); 3366 FD->setInvalidDecl(); 3367 EnclosingDecl->setInvalidDecl(); 3368 continue; 3369 } 3370 if (NumNamedMembers < 1) { //... must have more than named member ... 3371 Diag(FD->getLocation(), diag::err_flexible_array_empty_struct) 3372 << FD->getDeclName(); 3373 FD->setInvalidDecl(); 3374 EnclosingDecl->setInvalidDecl(); 3375 continue; 3376 } 3377 // Okay, we have a legal flexible array member at the end of the struct. 3378 if (Record) 3379 Record->setHasFlexibleArrayMember(true); 3380 } 3381 /// C99 6.7.2.1p2 - a struct ending in a flexible array member cannot be the 3382 /// field of another structure or the element of an array. 3383 if (const RecordType *FDTTy = FDTy->getAsRecordType()) { 3384 if (FDTTy->getDecl()->hasFlexibleArrayMember()) { 3385 // If this is a member of a union, then entire union becomes "flexible". 3386 if (Record && Record->isUnion()) { 3387 Record->setHasFlexibleArrayMember(true); 3388 } else { 3389 // If this is a struct/class and this is not the last element, reject 3390 // it. Note that GCC supports variable sized arrays in the middle of 3391 // structures. 3392 if (i != NumFields-1) { 3393 Diag(FD->getLocation(), diag::err_variable_sized_type_in_struct) 3394 << FD->getDeclName(); 3395 FD->setInvalidDecl(); 3396 EnclosingDecl->setInvalidDecl(); 3397 continue; 3398 } 3399 // We support flexible arrays at the end of structs in other structs 3400 // as an extension. 3401 Diag(FD->getLocation(), diag::ext_flexible_array_in_struct) 3402 << FD->getDeclName(); 3403 if (Record) 3404 Record->setHasFlexibleArrayMember(true); 3405 } 3406 } 3407 } 3408 /// A field cannot be an Objective-c object 3409 if (FDTy->isObjCInterfaceType()) { 3410 Diag(FD->getLocation(), diag::err_statically_allocated_object) 3411 << FD->getDeclName(); 3412 FD->setInvalidDecl(); 3413 EnclosingDecl->setInvalidDecl(); 3414 continue; 3415 } 3416 // Keep track of the number of named members. 3417 if (FD->getIdentifier()) 3418 ++NumNamedMembers; 3419 } 3420 3421 // Okay, we successfully defined 'Record'. 3422 if (Record) { 3423 Record->completeDefinition(Context); 3424 } else { 3425 ObjCIvarDecl **ClsFields = reinterpret_cast<ObjCIvarDecl**>(&RecFields[0]); 3426 if (ObjCInterfaceDecl *ID = dyn_cast<ObjCInterfaceDecl>(EnclosingDecl)) { 3427 ID->addInstanceVariablesToClass(ClsFields, RecFields.size(), RBrac); 3428 // Must enforce the rule that ivars in the base classes may not be 3429 // duplicates. 3430 if (ID->getSuperClass()) { 3431 for (ObjCInterfaceDecl::ivar_iterator IVI = ID->ivar_begin(), 3432 IVE = ID->ivar_end(); IVI != IVE; ++IVI) { 3433 ObjCIvarDecl* Ivar = (*IVI); 3434 IdentifierInfo *II = Ivar->getIdentifier(); 3435 ObjCIvarDecl* prevIvar = ID->getSuperClass()->FindIvarDeclaration(II); 3436 if (prevIvar) { 3437 Diag(Ivar->getLocation(), diag::err_duplicate_member) << II; 3438 Diag(prevIvar->getLocation(), diag::note_previous_declaration); 3439 } 3440 } 3441 } 3442 } 3443 else if (ObjCImplementationDecl *IMPDecl = 3444 dyn_cast<ObjCImplementationDecl>(EnclosingDecl)) { 3445 assert(IMPDecl && "ActOnFields - missing ObjCImplementationDecl"); 3446 IMPDecl->ObjCAddInstanceVariablesToClassImpl(ClsFields, RecFields.size()); 3447 CheckImplementationIvars(IMPDecl, ClsFields, RecFields.size(), RBrac); 3448 } 3449 } 3450 3451 if (Attr) 3452 ProcessDeclAttributeList(Record, Attr); 3453} 3454 3455Sema::DeclTy *Sema::ActOnEnumConstant(Scope *S, DeclTy *theEnumDecl, 3456 DeclTy *lastEnumConst, 3457 SourceLocation IdLoc, IdentifierInfo *Id, 3458 SourceLocation EqualLoc, ExprTy *val) { 3459 EnumDecl *TheEnumDecl = cast<EnumDecl>(static_cast<Decl*>(theEnumDecl)); 3460 EnumConstantDecl *LastEnumConst = 3461 cast_or_null<EnumConstantDecl>(static_cast<Decl*>(lastEnumConst)); 3462 Expr *Val = static_cast<Expr*>(val); 3463 3464 // The scope passed in may not be a decl scope. Zip up the scope tree until 3465 // we find one that is. 3466 S = getNonFieldDeclScope(S); 3467 3468 // Verify that there isn't already something declared with this name in this 3469 // scope. 3470 Decl *PrevDecl = LookupName(S, Id, LookupOrdinaryName); 3471 if (PrevDecl && PrevDecl->isTemplateParameter()) { 3472 // Maybe we will complain about the shadowed template parameter. 3473 DiagnoseTemplateParameterShadow(IdLoc, PrevDecl); 3474 // Just pretend that we didn't see the previous declaration. 3475 PrevDecl = 0; 3476 } 3477 3478 if (PrevDecl) { 3479 // When in C++, we may get a TagDecl with the same name; in this case the 3480 // enum constant will 'hide' the tag. 3481 assert((getLangOptions().CPlusPlus || !isa<TagDecl>(PrevDecl)) && 3482 "Received TagDecl when not in C++!"); 3483 if (!isa<TagDecl>(PrevDecl) && isDeclInScope(PrevDecl, CurContext, S)) { 3484 if (isa<EnumConstantDecl>(PrevDecl)) 3485 Diag(IdLoc, diag::err_redefinition_of_enumerator) << Id; 3486 else 3487 Diag(IdLoc, diag::err_redefinition) << Id; 3488 Diag(PrevDecl->getLocation(), diag::note_previous_definition); 3489 delete Val; 3490 return 0; 3491 } 3492 } 3493 3494 llvm::APSInt EnumVal(32); 3495 QualType EltTy; 3496 if (Val) { 3497 // Make sure to promote the operand type to int. 3498 UsualUnaryConversions(Val); 3499 3500 // C99 6.7.2.2p2: Make sure we have an integer constant expression. 3501 SourceLocation ExpLoc; 3502 if (VerifyIntegerConstantExpression(Val, &EnumVal)) { 3503 delete Val; 3504 Val = 0; // Just forget about it. 3505 } else { 3506 EltTy = Val->getType(); 3507 } 3508 } 3509 3510 if (!Val) { 3511 if (LastEnumConst) { 3512 // Assign the last value + 1. 3513 EnumVal = LastEnumConst->getInitVal(); 3514 ++EnumVal; 3515 3516 // Check for overflow on increment. 3517 if (EnumVal < LastEnumConst->getInitVal()) 3518 Diag(IdLoc, diag::warn_enum_value_overflow); 3519 3520 EltTy = LastEnumConst->getType(); 3521 } else { 3522 // First value, set to zero. 3523 EltTy = Context.IntTy; 3524 EnumVal.zextOrTrunc(static_cast<uint32_t>(Context.getTypeSize(EltTy))); 3525 } 3526 } 3527 3528 EnumConstantDecl *New = 3529 EnumConstantDecl::Create(Context, TheEnumDecl, IdLoc, Id, EltTy, 3530 Val, EnumVal); 3531 3532 // Register this decl in the current scope stack. 3533 PushOnScopeChains(New, S); 3534 3535 return New; 3536} 3537 3538// FIXME: For consistency with ActOnFields(), we should have the parser 3539// pass in the source location for the left/right braces. 3540void Sema::ActOnEnumBody(SourceLocation EnumLoc, DeclTy *EnumDeclX, 3541 DeclTy **Elements, unsigned NumElements) { 3542 EnumDecl *Enum = cast<EnumDecl>(static_cast<Decl*>(EnumDeclX)); 3543 QualType EnumType = Context.getTypeDeclType(Enum); 3544 3545 // TODO: If the result value doesn't fit in an int, it must be a long or long 3546 // long value. ISO C does not support this, but GCC does as an extension, 3547 // emit a warning. 3548 unsigned IntWidth = Context.Target.getIntWidth(); 3549 3550 // Verify that all the values are okay, compute the size of the values, and 3551 // reverse the list. 3552 unsigned NumNegativeBits = 0; 3553 unsigned NumPositiveBits = 0; 3554 3555 // Keep track of whether all elements have type int. 3556 bool AllElementsInt = true; 3557 3558 for (unsigned i = 0; i != NumElements; ++i) { 3559 EnumConstantDecl *ECD = 3560 cast_or_null<EnumConstantDecl>(static_cast<Decl*>(Elements[i])); 3561 if (!ECD) continue; // Already issued a diagnostic. 3562 3563 // If the enum value doesn't fit in an int, emit an extension warning. 3564 const llvm::APSInt &InitVal = ECD->getInitVal(); 3565 assert(InitVal.getBitWidth() >= IntWidth && 3566 "Should have promoted value to int"); 3567 if (InitVal.getBitWidth() > IntWidth) { 3568 llvm::APSInt V(InitVal); 3569 V.trunc(IntWidth); 3570 V.extend(InitVal.getBitWidth()); 3571 if (V != InitVal) 3572 Diag(ECD->getLocation(), diag::ext_enum_value_not_int) 3573 << InitVal.toString(10); 3574 } 3575 3576 // Keep track of the size of positive and negative values. 3577 if (InitVal.isUnsigned() || InitVal.isNonNegative()) 3578 NumPositiveBits = std::max(NumPositiveBits, 3579 (unsigned)InitVal.getActiveBits()); 3580 else 3581 NumNegativeBits = std::max(NumNegativeBits, 3582 (unsigned)InitVal.getMinSignedBits()); 3583 3584 // Keep track of whether every enum element has type int (very commmon). 3585 if (AllElementsInt) 3586 AllElementsInt = ECD->getType() == Context.IntTy; 3587 } 3588 3589 // Figure out the type that should be used for this enum. 3590 // FIXME: Support attribute(packed) on enums and -fshort-enums. 3591 QualType BestType; 3592 unsigned BestWidth; 3593 3594 if (NumNegativeBits) { 3595 // If there is a negative value, figure out the smallest integer type (of 3596 // int/long/longlong) that fits. 3597 if (NumNegativeBits <= IntWidth && NumPositiveBits < IntWidth) { 3598 BestType = Context.IntTy; 3599 BestWidth = IntWidth; 3600 } else { 3601 BestWidth = Context.Target.getLongWidth(); 3602 3603 if (NumNegativeBits <= BestWidth && NumPositiveBits < BestWidth) 3604 BestType = Context.LongTy; 3605 else { 3606 BestWidth = Context.Target.getLongLongWidth(); 3607 3608 if (NumNegativeBits > BestWidth || NumPositiveBits >= BestWidth) 3609 Diag(Enum->getLocation(), diag::warn_enum_too_large); 3610 BestType = Context.LongLongTy; 3611 } 3612 } 3613 } else { 3614 // If there is no negative value, figure out which of uint, ulong, ulonglong 3615 // fits. 3616 if (NumPositiveBits <= IntWidth) { 3617 BestType = Context.UnsignedIntTy; 3618 BestWidth = IntWidth; 3619 } else if (NumPositiveBits <= 3620 (BestWidth = Context.Target.getLongWidth())) { 3621 BestType = Context.UnsignedLongTy; 3622 } else { 3623 BestWidth = Context.Target.getLongLongWidth(); 3624 assert(NumPositiveBits <= BestWidth && 3625 "How could an initializer get larger than ULL?"); 3626 BestType = Context.UnsignedLongLongTy; 3627 } 3628 } 3629 3630 // Loop over all of the enumerator constants, changing their types to match 3631 // the type of the enum if needed. 3632 for (unsigned i = 0; i != NumElements; ++i) { 3633 EnumConstantDecl *ECD = 3634 cast_or_null<EnumConstantDecl>(static_cast<Decl*>(Elements[i])); 3635 if (!ECD) continue; // Already issued a diagnostic. 3636 3637 // Standard C says the enumerators have int type, but we allow, as an 3638 // extension, the enumerators to be larger than int size. If each 3639 // enumerator value fits in an int, type it as an int, otherwise type it the 3640 // same as the enumerator decl itself. This means that in "enum { X = 1U }" 3641 // that X has type 'int', not 'unsigned'. 3642 if (ECD->getType() == Context.IntTy) { 3643 // Make sure the init value is signed. 3644 llvm::APSInt IV = ECD->getInitVal(); 3645 IV.setIsSigned(true); 3646 ECD->setInitVal(IV); 3647 3648 if (getLangOptions().CPlusPlus) 3649 // C++ [dcl.enum]p4: Following the closing brace of an 3650 // enum-specifier, each enumerator has the type of its 3651 // enumeration. 3652 ECD->setType(EnumType); 3653 continue; // Already int type. 3654 } 3655 3656 // Determine whether the value fits into an int. 3657 llvm::APSInt InitVal = ECD->getInitVal(); 3658 bool FitsInInt; 3659 if (InitVal.isUnsigned() || !InitVal.isNegative()) 3660 FitsInInt = InitVal.getActiveBits() < IntWidth; 3661 else 3662 FitsInInt = InitVal.getMinSignedBits() <= IntWidth; 3663 3664 // If it fits into an integer type, force it. Otherwise force it to match 3665 // the enum decl type. 3666 QualType NewTy; 3667 unsigned NewWidth; 3668 bool NewSign; 3669 if (FitsInInt) { 3670 NewTy = Context.IntTy; 3671 NewWidth = IntWidth; 3672 NewSign = true; 3673 } else if (ECD->getType() == BestType) { 3674 // Already the right type! 3675 if (getLangOptions().CPlusPlus) 3676 // C++ [dcl.enum]p4: Following the closing brace of an 3677 // enum-specifier, each enumerator has the type of its 3678 // enumeration. 3679 ECD->setType(EnumType); 3680 continue; 3681 } else { 3682 NewTy = BestType; 3683 NewWidth = BestWidth; 3684 NewSign = BestType->isSignedIntegerType(); 3685 } 3686 3687 // Adjust the APSInt value. 3688 InitVal.extOrTrunc(NewWidth); 3689 InitVal.setIsSigned(NewSign); 3690 ECD->setInitVal(InitVal); 3691 3692 // Adjust the Expr initializer and type. 3693 if (ECD->getInitExpr()) 3694 ECD->setInitExpr(new ImplicitCastExpr(NewTy, ECD->getInitExpr(), 3695 /*isLvalue=*/false)); 3696 if (getLangOptions().CPlusPlus) 3697 // C++ [dcl.enum]p4: Following the closing brace of an 3698 // enum-specifier, each enumerator has the type of its 3699 // enumeration. 3700 ECD->setType(EnumType); 3701 else 3702 ECD->setType(NewTy); 3703 } 3704 3705 Enum->completeDefinition(Context, BestType); 3706} 3707 3708Sema::DeclTy *Sema::ActOnFileScopeAsmDecl(SourceLocation Loc, 3709 ExprArg expr) { 3710 StringLiteral *AsmString = cast<StringLiteral>((Expr*)expr.release()); 3711 3712 return FileScopeAsmDecl::Create(Context, CurContext, Loc, AsmString); 3713} 3714 3715 3716void Sema::ActOnPragmaPack(PragmaPackKind Kind, IdentifierInfo *Name, 3717 ExprTy *alignment, SourceLocation PragmaLoc, 3718 SourceLocation LParenLoc, SourceLocation RParenLoc) { 3719 Expr *Alignment = static_cast<Expr *>(alignment); 3720 3721 // If specified then alignment must be a "small" power of two. 3722 unsigned AlignmentVal = 0; 3723 if (Alignment) { 3724 llvm::APSInt Val; 3725 if (!Alignment->isIntegerConstantExpr(Val, Context) || 3726 !Val.isPowerOf2() || 3727 Val.getZExtValue() > 16) { 3728 Diag(PragmaLoc, diag::warn_pragma_pack_invalid_alignment); 3729 delete Alignment; 3730 return; // Ignore 3731 } 3732 3733 AlignmentVal = (unsigned) Val.getZExtValue(); 3734 } 3735 3736 switch (Kind) { 3737 case Action::PPK_Default: // pack([n]) 3738 PackContext.setAlignment(AlignmentVal); 3739 break; 3740 3741 case Action::PPK_Show: // pack(show) 3742 // Show the current alignment, making sure to show the right value 3743 // for the default. 3744 AlignmentVal = PackContext.getAlignment(); 3745 // FIXME: This should come from the target. 3746 if (AlignmentVal == 0) 3747 AlignmentVal = 8; 3748 Diag(PragmaLoc, diag::warn_pragma_pack_show) << AlignmentVal; 3749 break; 3750 3751 case Action::PPK_Push: // pack(push [, id] [, [n]) 3752 PackContext.push(Name); 3753 // Set the new alignment if specified. 3754 if (Alignment) 3755 PackContext.setAlignment(AlignmentVal); 3756 break; 3757 3758 case Action::PPK_Pop: // pack(pop [, id] [, n]) 3759 // MSDN, C/C++ Preprocessor Reference > Pragma Directives > pack: 3760 // "#pragma pack(pop, identifier, n) is undefined" 3761 if (Alignment && Name) 3762 Diag(PragmaLoc, diag::warn_pragma_pack_pop_identifer_and_alignment); 3763 3764 // Do the pop. 3765 if (!PackContext.pop(Name)) { 3766 // If a name was specified then failure indicates the name 3767 // wasn't found. Otherwise failure indicates the stack was 3768 // empty. 3769 Diag(PragmaLoc, diag::warn_pragma_pack_pop_failed) 3770 << (Name ? "no record matching name" : "stack empty"); 3771 3772 // FIXME: Warn about popping named records as MSVC does. 3773 } else { 3774 // Pop succeeded, set the new alignment if specified. 3775 if (Alignment) 3776 PackContext.setAlignment(AlignmentVal); 3777 } 3778 break; 3779 3780 default: 3781 assert(0 && "Invalid #pragma pack kind."); 3782 } 3783} 3784 3785bool PragmaPackStack::pop(IdentifierInfo *Name) { 3786 if (Stack.empty()) 3787 return false; 3788 3789 // If name is empty just pop top. 3790 if (!Name) { 3791 Alignment = Stack.back().first; 3792 Stack.pop_back(); 3793 return true; 3794 } 3795 3796 // Otherwise, find the named record. 3797 for (unsigned i = Stack.size(); i != 0; ) { 3798 --i; 3799 if (Stack[i].second == Name) { 3800 // Found it, pop up to and including this record. 3801 Alignment = Stack[i].first; 3802 Stack.erase(Stack.begin() + i, Stack.end()); 3803 return true; 3804 } 3805 } 3806 3807 return false; 3808} 3809