SemaDecl.cpp revision 72de6676bd30f9081ee4166bbe07b4c270258ce6
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/Diagnostic.h" 22#include "clang/Basic/TargetInfo.h" 23#include "clang/Basic/SourceManager.h" 24// FIXME: layering (ideally, Sema shouldn't be dependent on Lex API's) 25#include "clang/Lex/Preprocessor.h" 26#include "clang/Lex/HeaderSearch.h" 27#include "llvm/ADT/SmallSet.h" 28#include "llvm/ADT/STLExtras.h" 29#include <algorithm> 30#include <functional> 31 32using namespace clang; 33 34Sema::TypeTy *Sema::isTypeName(IdentifierInfo &II, Scope *S, 35 const CXXScopeSpec *SS) { 36 DeclContext *DC = 0; 37 if (SS) { 38 if (SS->isInvalid()) 39 return 0; 40 DC = static_cast<DeclContext*>(SS->getScopeRep()); 41 } 42 Decl *IIDecl = LookupDecl(&II, Decl::IDNS_Ordinary, S, DC, false); 43 44 if (IIDecl && (isa<TypedefDecl>(IIDecl) || 45 isa<ObjCInterfaceDecl>(IIDecl) || 46 isa<TagDecl>(IIDecl) || 47 isa<TemplateTypeParmDecl>(IIDecl))) 48 return IIDecl; 49 return 0; 50} 51 52DeclContext *Sema::getContainingDC(DeclContext *DC) { 53 if (CXXMethodDecl *MD = dyn_cast<CXXMethodDecl>(DC)) { 54 // A C++ out-of-line method will return to the file declaration context. 55 if (MD->isOutOfLineDefinition()) 56 return MD->getLexicalDeclContext(); 57 58 // A C++ inline method is parsed *after* the topmost class it was declared in 59 // is fully parsed (it's "complete"). 60 // The parsing of a C++ inline method happens at the declaration context of 61 // the topmost (non-nested) class it is lexically declared in. 62 assert(isa<CXXRecordDecl>(MD->getParent()) && "C++ method not in Record."); 63 DC = MD->getParent(); 64 while (CXXRecordDecl *RD = dyn_cast<CXXRecordDecl>(DC->getLexicalParent())) 65 DC = RD; 66 67 // Return the declaration context of the topmost class the inline method is 68 // declared in. 69 return DC; 70 } 71 72 if (isa<ObjCMethodDecl>(DC)) 73 return Context.getTranslationUnitDecl(); 74 75 if (ScopedDecl *SD = dyn_cast<ScopedDecl>(DC)) 76 return SD->getLexicalDeclContext(); 77 78 return DC->getLexicalParent(); 79} 80 81void Sema::PushDeclContext(Scope *S, DeclContext *DC) { 82 assert(getContainingDC(DC) == CurContext && 83 "The next DeclContext should be lexically contained in the current one."); 84 CurContext = DC; 85 S->setEntity(DC); 86} 87 88void Sema::PopDeclContext() { 89 assert(CurContext && "DeclContext imbalance!"); 90 91 CurContext = getContainingDC(CurContext); 92} 93 94/// Add this decl to the scope shadowed decl chains. 95void Sema::PushOnScopeChains(NamedDecl *D, Scope *S) { 96 // Move up the scope chain until we find the nearest enclosing 97 // non-transparent context. The declaration will be introduced into this 98 // scope. 99 while (S->getEntity() && 100 ((DeclContext *)S->getEntity())->isTransparentContext()) 101 S = S->getParent(); 102 103 S->AddDecl(D); 104 105 // Add scoped declarations into their context, so that they can be 106 // found later. Declarations without a context won't be inserted 107 // into any context. 108 if (ScopedDecl *SD = dyn_cast<ScopedDecl>(D)) 109 CurContext->addDecl(Context, SD); 110 111 // C++ [basic.scope]p4: 112 // -- exactly one declaration shall declare a class name or 113 // enumeration name that is not a typedef name and the other 114 // declarations shall all refer to the same object or 115 // enumerator, or all refer to functions and function templates; 116 // in this case the class name or enumeration name is hidden. 117 if (TagDecl *TD = dyn_cast<TagDecl>(D)) { 118 // We are pushing the name of a tag (enum or class). 119 if (CurContext->getLookupContext() 120 == TD->getDeclContext()->getLookupContext()) { 121 // We're pushing the tag into the current context, which might 122 // require some reshuffling in the identifier resolver. 123 IdentifierResolver::iterator 124 I = IdResolver.begin(TD->getDeclName(), CurContext, 125 false/*LookInParentCtx*/), 126 IEnd = IdResolver.end(); 127 if (I != IEnd && isDeclInScope(*I, CurContext, S)) { 128 NamedDecl *PrevDecl = *I; 129 for (; I != IEnd && isDeclInScope(*I, CurContext, S); 130 PrevDecl = *I, ++I) { 131 if (TD->declarationReplaces(*I)) { 132 // This is a redeclaration. Remove it from the chain and 133 // break out, so that we'll add in the shadowed 134 // declaration. 135 S->RemoveDecl(*I); 136 if (PrevDecl == *I) { 137 IdResolver.RemoveDecl(*I); 138 IdResolver.AddDecl(TD); 139 return; 140 } else { 141 IdResolver.RemoveDecl(*I); 142 break; 143 } 144 } 145 } 146 147 // There is already a declaration with the same name in the same 148 // scope, which is not a tag declaration. It must be found 149 // before we find the new declaration, so insert the new 150 // declaration at the end of the chain. 151 IdResolver.AddShadowedDecl(TD, PrevDecl); 152 153 return; 154 } 155 } 156 } else if (getLangOptions().CPlusPlus && isa<FunctionDecl>(D)) { 157 // We are pushing the name of a function, which might be an 158 // overloaded name. 159 FunctionDecl *FD = cast<FunctionDecl>(D); 160 DeclContext *DC = FD->getDeclContext()->getLookupContext(); 161 IdentifierResolver::iterator Redecl 162 = std::find_if(IdResolver.begin(FD->getDeclName(), DC, 163 false/*LookInParentCtx*/), 164 IdResolver.end(), 165 std::bind1st(std::mem_fun(&ScopedDecl::declarationReplaces), 166 FD)); 167 if (Redecl != IdResolver.end()) { 168 // There is already a declaration of a function on our 169 // IdResolver chain. Replace it with this declaration. 170 S->RemoveDecl(*Redecl); 171 IdResolver.RemoveDecl(*Redecl); 172 } 173 } 174 175 IdResolver.AddDecl(D); 176} 177 178void Sema::ActOnPopScope(SourceLocation Loc, Scope *S) { 179 if (S->decl_empty()) return; 180 assert((S->getFlags() & (Scope::DeclScope | Scope::TemplateParamScope)) && 181 "Scope shouldn't contain decls!"); 182 183 for (Scope::decl_iterator I = S->decl_begin(), E = S->decl_end(); 184 I != E; ++I) { 185 Decl *TmpD = static_cast<Decl*>(*I); 186 assert(TmpD && "This decl didn't get pushed??"); 187 188 assert(isa<NamedDecl>(TmpD) && "Decl isn't NamedDecl?"); 189 NamedDecl *D = cast<NamedDecl>(TmpD); 190 191 if (!D->getDeclName()) continue; 192 193 // Remove this name from our lexical scope. 194 IdResolver.RemoveDecl(D); 195 } 196} 197 198/// getObjCInterfaceDecl - Look up a for a class declaration in the scope. 199/// return 0 if one not found. 200ObjCInterfaceDecl *Sema::getObjCInterfaceDecl(IdentifierInfo *Id) { 201 // The third "scope" argument is 0 since we aren't enabling lazy built-in 202 // creation from this context. 203 Decl *IDecl = LookupDecl(Id, Decl::IDNS_Ordinary, 0, false); 204 205 return dyn_cast_or_null<ObjCInterfaceDecl>(IDecl); 206} 207 208/// MaybeConstructOverloadSet - Name lookup has determined that the 209/// elements in [I, IEnd) have the name that we are looking for, and 210/// *I is a match for the namespace. This routine returns an 211/// appropriate Decl for name lookup, which may either be *I or an 212/// OverloadeFunctionDecl that represents the overloaded functions in 213/// [I, IEnd). 214/// 215/// The existance of this routine is temporary; LookupDecl should 216/// probably be able to return multiple results, to deal with cases of 217/// ambiguity and overloaded functions without needing to create a 218/// Decl node. 219template<typename DeclIterator> 220static Decl * 221MaybeConstructOverloadSet(ASTContext &Context, 222 DeclIterator I, DeclIterator IEnd) { 223 assert(I != IEnd && "Iterator range cannot be empty"); 224 assert(!isa<OverloadedFunctionDecl>(*I) && 225 "Cannot have an overloaded function"); 226 227 if (isa<FunctionDecl>(*I)) { 228 // If we found a function, there might be more functions. If 229 // so, collect them into an overload set. 230 DeclIterator Last = I; 231 OverloadedFunctionDecl *Ovl = 0; 232 for (++Last; Last != IEnd && isa<FunctionDecl>(*Last); ++Last) { 233 if (!Ovl) { 234 // FIXME: We leak this overload set. Eventually, we want to 235 // stop building the declarations for these overload sets, so 236 // there will be nothing to leak. 237 Ovl = OverloadedFunctionDecl::Create(Context, 238 cast<ScopedDecl>(*I)->getDeclContext(), 239 (*I)->getDeclName()); 240 Ovl->addOverload(cast<FunctionDecl>(*I)); 241 } 242 Ovl->addOverload(cast<FunctionDecl>(*Last)); 243 } 244 245 // If we had more than one function, we built an overload 246 // set. Return it. 247 if (Ovl) 248 return Ovl; 249 } 250 251 return *I; 252} 253 254/// LookupDecl - Look up the inner-most declaration in the specified 255/// namespace. NamespaceNameOnly - during lookup only namespace names 256/// are considered as required in C++ [basic.lookup.udir] 3.4.6.p1 257/// 'When looking up a namespace-name in a using-directive or 258/// namespace-alias-definition, only namespace names are considered.' 259Decl *Sema::LookupDecl(DeclarationName Name, unsigned NSI, Scope *S, 260 const DeclContext *LookupCtx, 261 bool enableLazyBuiltinCreation, 262 bool LookInParent, 263 bool NamespaceNameOnly) { 264 if (!Name) return 0; 265 unsigned NS = NSI; 266 267 // In C++, ordinary and member lookup will always find all 268 // kinds of names. 269 if (getLangOptions().CPlusPlus && 270 (NS & (Decl::IDNS_Ordinary | Decl::IDNS_Member))) 271 NS |= Decl::IDNS_Tag | Decl::IDNS_Member | Decl::IDNS_Ordinary; 272 273 if (LookupCtx == 0 && !getLangOptions().CPlusPlus) { 274 // Unqualified name lookup in C/Objective-C is purely lexical, so 275 // search in the declarations attached to the name. 276 assert(!LookupCtx && "Can't perform qualified name lookup here"); 277 assert(!NamespaceNameOnly && "Can't perform namespace name lookup here"); 278 279 // For the purposes of unqualified name lookup, structs and unions 280 // don't have scopes at all. For example: 281 // 282 // struct X { 283 // struct T { int i; } x; 284 // }; 285 // 286 // void f() { 287 // struct T t; // okay: T is defined lexically within X, but 288 // // semantically at global scope 289 // }; 290 // 291 // FIXME: Is there a better way to deal with this? 292 DeclContext *SearchCtx = CurContext; 293 while (isa<RecordDecl>(SearchCtx) || isa<EnumDecl>(SearchCtx)) 294 SearchCtx = SearchCtx->getParent(); 295 IdentifierResolver::iterator I 296 = IdResolver.begin(Name, SearchCtx, LookInParent); 297 298 // Scan up the scope chain looking for a decl that matches this 299 // identifier that is in the appropriate namespace. This search 300 // should not take long, as shadowing of names is uncommon, and 301 // deep shadowing is extremely uncommon. 302 for (; I != IdResolver.end(); ++I) 303 if ((*I)->isInIdentifierNamespace(NS)) 304 return *I; 305 } else if (LookupCtx) { 306 // If we're performing qualified name lookup (e.g., lookup into a 307 // struct), find fields as part of ordinary name lookup. 308 if (NS & Decl::IDNS_Ordinary) 309 NS |= Decl::IDNS_Member; 310 311 // Perform qualified name lookup into the LookupCtx. 312 // FIXME: Will need to look into base classes and such. 313 DeclContext::lookup_const_iterator I, E; 314 for (llvm::tie(I, E) = LookupCtx->lookup(Name); I != E; ++I) 315 if ((*I)->isInIdentifierNamespace(NS)) { 316 // Ignore non-namespace names if we're only looking for namespaces. 317 if (NamespaceNameOnly && !isa<NamespaceDecl>(*I)) continue; 318 319 return MaybeConstructOverloadSet(Context, I, E); 320 } 321 } else { 322 // Name lookup for ordinary names and tag names in C++ requires 323 // looking into scopes that aren't strictly lexical, and 324 // therefore we walk through the context as well as walking 325 // through the scopes. 326 IdentifierResolver::iterator 327 I = IdResolver.begin(Name, CurContext, true/*LookInParentCtx*/), 328 IEnd = IdResolver.end(); 329 for (; S; S = S->getParent()) { 330 // Check whether the IdResolver has anything in this scope. 331 // FIXME: The isDeclScope check could be expensive. Can we do better? 332 for (; I != IEnd && S->isDeclScope(*I); ++I) { 333 if ((*I)->isInIdentifierNamespace(NS)) { 334 // Ignore non-namespace names if we're only looking for namespaces. 335 if (NamespaceNameOnly && !isa<NamespaceDecl>(*I)) 336 continue; 337 338 // We found something. Look for anything else in our scope 339 // with this same name and in an acceptable identifier 340 // namespace, so that we can construct an overload set if we 341 // need to. 342 IdentifierResolver::iterator LastI = I; 343 for (++LastI; LastI != IEnd; ++LastI) { 344 if (!(*LastI)->isInIdentifierNamespace(NS) || 345 !S->isDeclScope(*LastI)) 346 break; 347 } 348 return MaybeConstructOverloadSet(Context, I, LastI); 349 } 350 } 351 352 // If there is an entity associated with this scope, it's a 353 // DeclContext. We might need to perform qualified lookup into 354 // it. 355 DeclContext *Ctx = static_cast<DeclContext *>(S->getEntity()); 356 while (Ctx && Ctx->isFunctionOrMethod()) 357 Ctx = Ctx->getParent(); 358 while (Ctx && (Ctx->isNamespace() || Ctx->isRecord())) { 359 // Look for declarations of this name in this scope. 360 DeclContext::lookup_const_iterator I, E; 361 for (llvm::tie(I, E) = Ctx->lookup(Name); I != E; ++I) { 362 // FIXME: Cache this result in the IdResolver 363 if ((*I)->isInIdentifierNamespace(NS)) { 364 if (NamespaceNameOnly && !isa<NamespaceDecl>(*I)) 365 continue; 366 return MaybeConstructOverloadSet(Context, I, E); 367 } 368 } 369 370 if (!LookInParent && !Ctx->isTransparentContext()) 371 return 0; 372 373 Ctx = Ctx->getParent(); 374 } 375 } 376 } 377 378 // If we didn't find a use of this identifier, and if the identifier 379 // corresponds to a compiler builtin, create the decl object for the builtin 380 // now, injecting it into translation unit scope, and return it. 381 if (NS & Decl::IDNS_Ordinary) { 382 IdentifierInfo *II = Name.getAsIdentifierInfo(); 383 if (enableLazyBuiltinCreation && II && 384 (LookupCtx == 0 || isa<TranslationUnitDecl>(LookupCtx))) { 385 // If this is a builtin on this (or all) targets, create the decl. 386 if (unsigned BuiltinID = II->getBuiltinID()) 387 return LazilyCreateBuiltin((IdentifierInfo *)II, BuiltinID, S); 388 } 389 if (getLangOptions().ObjC1 && II) { 390 // @interface and @compatibility_alias introduce typedef-like names. 391 // Unlike typedef's, they can only be introduced at file-scope (and are 392 // therefore not scoped decls). They can, however, be shadowed by 393 // other names in IDNS_Ordinary. 394 ObjCInterfaceDeclsTy::iterator IDI = ObjCInterfaceDecls.find(II); 395 if (IDI != ObjCInterfaceDecls.end()) 396 return IDI->second; 397 ObjCAliasTy::iterator I = ObjCAliasDecls.find(II); 398 if (I != ObjCAliasDecls.end()) 399 return I->second->getClassInterface(); 400 } 401 } 402 return 0; 403} 404 405void Sema::InitBuiltinVaListType() { 406 if (!Context.getBuiltinVaListType().isNull()) 407 return; 408 409 IdentifierInfo *VaIdent = &Context.Idents.get("__builtin_va_list"); 410 Decl *VaDecl = LookupDecl(VaIdent, Decl::IDNS_Ordinary, TUScope); 411 TypedefDecl *VaTypedef = cast<TypedefDecl>(VaDecl); 412 Context.setBuiltinVaListType(Context.getTypedefType(VaTypedef)); 413} 414 415/// LazilyCreateBuiltin - The specified Builtin-ID was first used at file scope. 416/// lazily create a decl for it. 417ScopedDecl *Sema::LazilyCreateBuiltin(IdentifierInfo *II, unsigned bid, 418 Scope *S) { 419 Builtin::ID BID = (Builtin::ID)bid; 420 421 if (Context.BuiltinInfo.hasVAListUse(BID)) 422 InitBuiltinVaListType(); 423 424 QualType R = Context.BuiltinInfo.GetBuiltinType(BID, Context); 425 FunctionDecl *New = FunctionDecl::Create(Context, 426 Context.getTranslationUnitDecl(), 427 SourceLocation(), II, R, 428 FunctionDecl::Extern, false, 0); 429 430 // Create Decl objects for each parameter, adding them to the 431 // FunctionDecl. 432 if (FunctionTypeProto *FT = dyn_cast<FunctionTypeProto>(R)) { 433 llvm::SmallVector<ParmVarDecl*, 16> Params; 434 for (unsigned i = 0, e = FT->getNumArgs(); i != e; ++i) 435 Params.push_back(ParmVarDecl::Create(Context, New, SourceLocation(), 0, 436 FT->getArgType(i), VarDecl::None, 0, 437 0)); 438 New->setParams(&Params[0], Params.size()); 439 } 440 441 442 443 // TUScope is the translation-unit scope to insert this function into. 444 PushOnScopeChains(New, TUScope); 445 return New; 446} 447 448/// GetStdNamespace - This method gets the C++ "std" namespace. This is where 449/// everything from the standard library is defined. 450NamespaceDecl *Sema::GetStdNamespace() { 451 if (!StdNamespace) { 452 IdentifierInfo *StdIdent = &PP.getIdentifierTable().get("std"); 453 DeclContext *Global = Context.getTranslationUnitDecl(); 454 Decl *Std = LookupDecl(StdIdent, Decl::IDNS_Tag | Decl::IDNS_Ordinary, 455 0, Global, /*enableLazyBuiltinCreation=*/false); 456 StdNamespace = dyn_cast_or_null<NamespaceDecl>(Std); 457 } 458 return StdNamespace; 459} 460 461/// MergeTypeDefDecl - We just parsed a typedef 'New' which has the same name 462/// and scope as a previous declaration 'Old'. Figure out how to resolve this 463/// situation, merging decls or emitting diagnostics as appropriate. 464/// 465TypedefDecl *Sema::MergeTypeDefDecl(TypedefDecl *New, Decl *OldD) { 466 // Allow multiple definitions for ObjC built-in typedefs. 467 // FIXME: Verify the underlying types are equivalent! 468 if (getLangOptions().ObjC1) { 469 const IdentifierInfo *TypeID = New->getIdentifier(); 470 switch (TypeID->getLength()) { 471 default: break; 472 case 2: 473 if (!TypeID->isStr("id")) 474 break; 475 Context.setObjCIdType(New); 476 return New; 477 case 5: 478 if (!TypeID->isStr("Class")) 479 break; 480 Context.setObjCClassType(New); 481 return New; 482 case 3: 483 if (!TypeID->isStr("SEL")) 484 break; 485 Context.setObjCSelType(New); 486 return New; 487 case 8: 488 if (!TypeID->isStr("Protocol")) 489 break; 490 Context.setObjCProtoType(New->getUnderlyingType()); 491 return New; 492 } 493 // Fall through - the typedef name was not a builtin type. 494 } 495 // Verify the old decl was also a typedef. 496 TypedefDecl *Old = dyn_cast<TypedefDecl>(OldD); 497 if (!Old) { 498 Diag(New->getLocation(), diag::err_redefinition_different_kind) 499 << New->getDeclName(); 500 Diag(OldD->getLocation(), diag::note_previous_definition); 501 return New; 502 } 503 504 // If the typedef types are not identical, reject them in all languages and 505 // with any extensions enabled. 506 if (Old->getUnderlyingType() != New->getUnderlyingType() && 507 Context.getCanonicalType(Old->getUnderlyingType()) != 508 Context.getCanonicalType(New->getUnderlyingType())) { 509 Diag(New->getLocation(), diag::err_redefinition_different_typedef) 510 << New->getUnderlyingType() << Old->getUnderlyingType(); 511 Diag(Old->getLocation(), diag::note_previous_definition); 512 return Old; 513 } 514 515 if (getLangOptions().Microsoft) return New; 516 517 // C++ [dcl.typedef]p2: 518 // In a given non-class scope, a typedef specifier can be used to 519 // redefine the name of any type declared in that scope to refer 520 // to the type to which it already refers. 521 if (getLangOptions().CPlusPlus && !isa<CXXRecordDecl>(CurContext)) 522 return New; 523 524 // In C, redeclaration of a type is a constraint violation (6.7.2.3p1). 525 // Apparently GCC, Intel, and Sun all silently ignore the redeclaration if 526 // *either* declaration is in a system header. The code below implements 527 // this adhoc compatibility rule. FIXME: The following code will not 528 // work properly when compiling ".i" files (containing preprocessed output). 529 if (PP.getDiagnostics().getSuppressSystemWarnings()) { 530 SourceManager &SrcMgr = Context.getSourceManager(); 531 if (SrcMgr.isInSystemHeader(Old->getLocation())) 532 return New; 533 if (SrcMgr.isInSystemHeader(New->getLocation())) 534 return New; 535 } 536 537 Diag(New->getLocation(), diag::err_redefinition) << New->getDeclName(); 538 Diag(Old->getLocation(), diag::note_previous_definition); 539 return New; 540} 541 542/// DeclhasAttr - returns true if decl Declaration already has the target 543/// attribute. 544static bool DeclHasAttr(const Decl *decl, const Attr *target) { 545 for (const Attr *attr = decl->getAttrs(); attr; attr = attr->getNext()) 546 if (attr->getKind() == target->getKind()) 547 return true; 548 549 return false; 550} 551 552/// MergeAttributes - append attributes from the Old decl to the New one. 553static void MergeAttributes(Decl *New, Decl *Old) { 554 Attr *attr = const_cast<Attr*>(Old->getAttrs()), *tmp; 555 556 while (attr) { 557 tmp = attr; 558 attr = attr->getNext(); 559 560 if (!DeclHasAttr(New, tmp)) { 561 tmp->setInherited(true); 562 New->addAttr(tmp); 563 } else { 564 tmp->setNext(0); 565 delete(tmp); 566 } 567 } 568 569 Old->invalidateAttrs(); 570} 571 572/// MergeFunctionDecl - We just parsed a function 'New' from 573/// declarator D which has the same name and scope as a previous 574/// declaration 'Old'. Figure out how to resolve this situation, 575/// merging decls or emitting diagnostics as appropriate. 576/// Redeclaration will be set true if this New is a redeclaration OldD. 577/// 578/// In C++, New and Old must be declarations that are not 579/// overloaded. Use IsOverload to determine whether New and Old are 580/// overloaded, and to select the Old declaration that New should be 581/// merged with. 582FunctionDecl * 583Sema::MergeFunctionDecl(FunctionDecl *New, Decl *OldD, bool &Redeclaration) { 584 assert(!isa<OverloadedFunctionDecl>(OldD) && 585 "Cannot merge with an overloaded function declaration"); 586 587 Redeclaration = false; 588 // Verify the old decl was also a function. 589 FunctionDecl *Old = dyn_cast<FunctionDecl>(OldD); 590 if (!Old) { 591 Diag(New->getLocation(), diag::err_redefinition_different_kind) 592 << New->getDeclName(); 593 Diag(OldD->getLocation(), diag::note_previous_definition); 594 return New; 595 } 596 597 // Determine whether the previous declaration was a definition, 598 // implicit declaration, or a declaration. 599 diag::kind PrevDiag; 600 if (Old->isThisDeclarationADefinition()) 601 PrevDiag = diag::note_previous_definition; 602 else if (Old->isImplicit()) 603 PrevDiag = diag::note_previous_implicit_declaration; 604 else 605 PrevDiag = diag::note_previous_declaration; 606 607 QualType OldQType = Context.getCanonicalType(Old->getType()); 608 QualType NewQType = Context.getCanonicalType(New->getType()); 609 610 if (getLangOptions().CPlusPlus) { 611 // (C++98 13.1p2): 612 // Certain function declarations cannot be overloaded: 613 // -- Function declarations that differ only in the return type 614 // cannot be overloaded. 615 QualType OldReturnType 616 = cast<FunctionType>(OldQType.getTypePtr())->getResultType(); 617 QualType NewReturnType 618 = cast<FunctionType>(NewQType.getTypePtr())->getResultType(); 619 if (OldReturnType != NewReturnType) { 620 Diag(New->getLocation(), diag::err_ovl_diff_return_type); 621 Diag(Old->getLocation(), PrevDiag); 622 Redeclaration = true; 623 return New; 624 } 625 626 const CXXMethodDecl* OldMethod = dyn_cast<CXXMethodDecl>(Old); 627 const CXXMethodDecl* NewMethod = dyn_cast<CXXMethodDecl>(New); 628 if (OldMethod && NewMethod) { 629 // -- Member function declarations with the same name and the 630 // same parameter types cannot be overloaded if any of them 631 // is a static member function declaration. 632 if (OldMethod->isStatic() || NewMethod->isStatic()) { 633 Diag(New->getLocation(), diag::err_ovl_static_nonstatic_member); 634 Diag(Old->getLocation(), PrevDiag); 635 return New; 636 } 637 638 // C++ [class.mem]p1: 639 // [...] A member shall not be declared twice in the 640 // member-specification, except that a nested class or member 641 // class template can be declared and then later defined. 642 if (OldMethod->getLexicalDeclContext() == 643 NewMethod->getLexicalDeclContext()) { 644 unsigned NewDiag; 645 if (isa<CXXConstructorDecl>(OldMethod)) 646 NewDiag = diag::err_constructor_redeclared; 647 else if (isa<CXXDestructorDecl>(NewMethod)) 648 NewDiag = diag::err_destructor_redeclared; 649 else if (isa<CXXConversionDecl>(NewMethod)) 650 NewDiag = diag::err_conv_function_redeclared; 651 else 652 NewDiag = diag::err_member_redeclared; 653 654 Diag(New->getLocation(), NewDiag); 655 Diag(Old->getLocation(), PrevDiag); 656 } 657 } 658 659 // (C++98 8.3.5p3): 660 // All declarations for a function shall agree exactly in both the 661 // return type and the parameter-type-list. 662 if (OldQType == NewQType) { 663 // We have a redeclaration. 664 MergeAttributes(New, Old); 665 Redeclaration = true; 666 return MergeCXXFunctionDecl(New, Old); 667 } 668 669 // Fall through for conflicting redeclarations and redefinitions. 670 } 671 672 // C: Function types need to be compatible, not identical. This handles 673 // duplicate function decls like "void f(int); void f(enum X);" properly. 674 if (!getLangOptions().CPlusPlus && 675 Context.typesAreCompatible(OldQType, NewQType)) { 676 MergeAttributes(New, Old); 677 Redeclaration = true; 678 return New; 679 } 680 681 // A function that has already been declared has been redeclared or defined 682 // with a different type- show appropriate diagnostic 683 684 // TODO: CHECK FOR CONFLICTS, multiple decls with same name in one scope. 685 // TODO: This is totally simplistic. It should handle merging functions 686 // together etc, merging extern int X; int X; ... 687 Diag(New->getLocation(), diag::err_conflicting_types) << New->getDeclName(); 688 Diag(Old->getLocation(), PrevDiag); 689 return New; 690} 691 692/// Predicate for C "tentative" external object definitions (C99 6.9.2). 693static bool isTentativeDefinition(VarDecl *VD) { 694 if (VD->isFileVarDecl()) 695 return (!VD->getInit() && 696 (VD->getStorageClass() == VarDecl::None || 697 VD->getStorageClass() == VarDecl::Static)); 698 return false; 699} 700 701/// CheckForFileScopedRedefinitions - Make sure we forgo redefinition errors 702/// when dealing with C "tentative" external object definitions (C99 6.9.2). 703void Sema::CheckForFileScopedRedefinitions(Scope *S, VarDecl *VD) { 704 bool VDIsTentative = isTentativeDefinition(VD); 705 bool VDIsIncompleteArray = VD->getType()->isIncompleteArrayType(); 706 707 // FIXME: I don't think this will actually see all of the 708 // redefinitions. Can't we check this property on-the-fly? 709 for (IdentifierResolver::iterator 710 I = IdResolver.begin(VD->getIdentifier(), 711 VD->getDeclContext(), false/*LookInParentCtx*/), 712 E = IdResolver.end(); I != E; ++I) { 713 if (*I != VD && isDeclInScope(*I, VD->getDeclContext(), S)) { 714 VarDecl *OldDecl = dyn_cast<VarDecl>(*I); 715 716 // Handle the following case: 717 // int a[10]; 718 // int a[]; - the code below makes sure we set the correct type. 719 // int a[11]; - this is an error, size isn't 10. 720 if (OldDecl && VDIsTentative && VDIsIncompleteArray && 721 OldDecl->getType()->isConstantArrayType()) 722 VD->setType(OldDecl->getType()); 723 724 // Check for "tentative" definitions. We can't accomplish this in 725 // MergeVarDecl since the initializer hasn't been attached. 726 if (!OldDecl || isTentativeDefinition(OldDecl) || VDIsTentative) 727 continue; 728 729 // Handle __private_extern__ just like extern. 730 if (OldDecl->getStorageClass() != VarDecl::Extern && 731 OldDecl->getStorageClass() != VarDecl::PrivateExtern && 732 VD->getStorageClass() != VarDecl::Extern && 733 VD->getStorageClass() != VarDecl::PrivateExtern) { 734 Diag(VD->getLocation(), diag::err_redefinition) << VD->getDeclName(); 735 Diag(OldDecl->getLocation(), diag::note_previous_definition); 736 } 737 } 738 } 739} 740 741/// MergeVarDecl - We just parsed a variable 'New' which has the same name 742/// and scope as a previous declaration 'Old'. Figure out how to resolve this 743/// situation, merging decls or emitting diagnostics as appropriate. 744/// 745/// Tentative definition rules (C99 6.9.2p2) are checked by 746/// FinalizeDeclaratorGroup. Unfortunately, we can't analyze tentative 747/// definitions here, since the initializer hasn't been attached. 748/// 749VarDecl *Sema::MergeVarDecl(VarDecl *New, Decl *OldD) { 750 // Verify the old decl was also a variable. 751 VarDecl *Old = dyn_cast<VarDecl>(OldD); 752 if (!Old) { 753 Diag(New->getLocation(), diag::err_redefinition_different_kind) 754 << New->getDeclName(); 755 Diag(OldD->getLocation(), diag::note_previous_definition); 756 return New; 757 } 758 759 MergeAttributes(New, Old); 760 761 // Verify the types match. 762 QualType OldCType = Context.getCanonicalType(Old->getType()); 763 QualType NewCType = Context.getCanonicalType(New->getType()); 764 if (OldCType != NewCType && !Context.typesAreCompatible(OldCType, NewCType)) { 765 Diag(New->getLocation(), diag::err_redefinition) << New->getDeclName(); 766 Diag(Old->getLocation(), diag::note_previous_definition); 767 return New; 768 } 769 // C99 6.2.2p4: Check if we have a static decl followed by a non-static. 770 if (New->getStorageClass() == VarDecl::Static && 771 (Old->getStorageClass() == VarDecl::None || 772 Old->getStorageClass() == VarDecl::Extern)) { 773 Diag(New->getLocation(), diag::err_static_non_static) << New->getDeclName(); 774 Diag(Old->getLocation(), diag::note_previous_definition); 775 return New; 776 } 777 // C99 6.2.2p4: Check if we have a non-static decl followed by a static. 778 if (New->getStorageClass() != VarDecl::Static && 779 Old->getStorageClass() == VarDecl::Static) { 780 Diag(New->getLocation(), diag::err_non_static_static) << New->getDeclName(); 781 Diag(Old->getLocation(), diag::note_previous_definition); 782 return New; 783 } 784 // Variables with external linkage are analyzed in FinalizeDeclaratorGroup. 785 if (New->getStorageClass() != VarDecl::Extern && !New->isFileVarDecl()) { 786 Diag(New->getLocation(), diag::err_redefinition) << New->getDeclName(); 787 Diag(Old->getLocation(), diag::note_previous_definition); 788 } 789 return New; 790} 791 792/// CheckParmsForFunctionDef - Check that the parameters of the given 793/// function are appropriate for the definition of a function. This 794/// takes care of any checks that cannot be performed on the 795/// declaration itself, e.g., that the types of each of the function 796/// parameters are complete. 797bool Sema::CheckParmsForFunctionDef(FunctionDecl *FD) { 798 bool HasInvalidParm = false; 799 for (unsigned p = 0, NumParams = FD->getNumParams(); p < NumParams; ++p) { 800 ParmVarDecl *Param = FD->getParamDecl(p); 801 802 // C99 6.7.5.3p4: the parameters in a parameter type list in a 803 // function declarator that is part of a function definition of 804 // that function shall not have incomplete type. 805 if (Param->getType()->isIncompleteType() && 806 !Param->isInvalidDecl()) { 807 Diag(Param->getLocation(), diag::err_typecheck_decl_incomplete_type) 808 << Param->getType(); 809 Param->setInvalidDecl(); 810 HasInvalidParm = true; 811 } 812 813 // C99 6.9.1p5: If the declarator includes a parameter type list, the 814 // declaration of each parameter shall include an identifier. 815 if (Param->getIdentifier() == 0 && !getLangOptions().CPlusPlus) 816 Diag(Param->getLocation(), diag::err_parameter_name_omitted); 817 } 818 819 return HasInvalidParm; 820} 821 822/// ParsedFreeStandingDeclSpec - This method is invoked when a declspec with 823/// no declarator (e.g. "struct foo;") is parsed. 824Sema::DeclTy *Sema::ParsedFreeStandingDeclSpec(Scope *S, DeclSpec &DS) { 825 // FIXME: Isn't that more of a parser diagnostic than a sema diagnostic? 826 if (!DS.isMissingDeclaratorOk()) { 827 // FIXME: This diagnostic is emitted even when various previous 828 // errors occurred (see e.g. test/Sema/decl-invalid.c). However, 829 // DeclSpec has no means of communicating this information, and the 830 // responsible parser functions are quite far apart. 831 Diag(DS.getSourceRange().getBegin(), diag::err_no_declarators) 832 << DS.getSourceRange(); 833 return 0; 834 } 835 836 TagDecl *Tag 837 = dyn_cast_or_null<TagDecl>(static_cast<Decl *>(DS.getTypeRep())); 838 if (RecordDecl *Record = dyn_cast_or_null<RecordDecl>(Tag)) { 839 if (!Record->getDeclName() && Record->isDefinition() && 840 !Record->isInvalidDecl()) 841 return BuildAnonymousStructOrUnion(S, DS, Record); 842 } 843 844 return Tag; 845} 846 847/// InjectAnonymousStructOrUnionMembers - Inject the members of the 848/// anonymous struct or union AnonRecord into the owning context Owner 849/// and scope S. This routine will be invoked just after we realize 850/// that an unnamed union or struct is actually an anonymous union or 851/// struct, e.g., 852/// 853/// @code 854/// union { 855/// int i; 856/// float f; 857/// }; // InjectAnonymousStructOrUnionMembers called here to inject i and 858/// // f into the surrounding scope.x 859/// @endcode 860/// 861/// This routine is recursive, injecting the names of nested anonymous 862/// structs/unions into the owning context and scope as well. 863bool Sema::InjectAnonymousStructOrUnionMembers(Scope *S, DeclContext *Owner, 864 RecordDecl *AnonRecord) { 865 bool Invalid = false; 866 for (RecordDecl::field_iterator F = AnonRecord->field_begin(), 867 FEnd = AnonRecord->field_end(); 868 F != FEnd; ++F) { 869 if ((*F)->getDeclName()) { 870 Decl *PrevDecl = LookupDecl((*F)->getDeclName(), Decl::IDNS_Ordinary, 871 S, Owner, false, false, false); 872 if (PrevDecl && !isa<TagDecl>(PrevDecl)) { 873 // C++ [class.union]p2: 874 // The names of the members of an anonymous union shall be 875 // distinct from the names of any other entity in the 876 // scope in which the anonymous union is declared. 877 unsigned diagKind 878 = AnonRecord->isUnion()? diag::err_anonymous_union_member_redecl 879 : diag::err_anonymous_struct_member_redecl; 880 Diag((*F)->getLocation(), diagKind) 881 << (*F)->getDeclName(); 882 Diag(PrevDecl->getLocation(), diag::note_previous_declaration); 883 Invalid = true; 884 } else { 885 // C++ [class.union]p2: 886 // For the purpose of name lookup, after the anonymous union 887 // definition, the members of the anonymous union are 888 // considered to have been defined in the scope in which the 889 // anonymous union is declared. 890 Owner->insert(Context, *F); 891 S->AddDecl(*F); 892 IdResolver.AddDecl(*F); 893 } 894 } else if (const RecordType *InnerRecordType 895 = (*F)->getType()->getAsRecordType()) { 896 RecordDecl *InnerRecord = InnerRecordType->getDecl(); 897 if (InnerRecord->isAnonymousStructOrUnion()) 898 Invalid = Invalid || 899 InjectAnonymousStructOrUnionMembers(S, Owner, InnerRecord); 900 } 901 } 902 903 return Invalid; 904} 905 906/// ActOnAnonymousStructOrUnion - Handle the declaration of an 907/// anonymous structure or union. Anonymous unions are a C++ feature 908/// (C++ [class.union]) and a GNU C extension; anonymous structures 909/// are a GNU C and GNU C++ extension. 910Sema::DeclTy *Sema::BuildAnonymousStructOrUnion(Scope *S, DeclSpec &DS, 911 RecordDecl *Record) { 912 DeclContext *Owner = Record->getDeclContext(); 913 914 // Diagnose whether this anonymous struct/union is an extension. 915 if (Record->isUnion() && !getLangOptions().CPlusPlus) 916 Diag(Record->getLocation(), diag::ext_anonymous_union); 917 else if (!Record->isUnion()) 918 Diag(Record->getLocation(), diag::ext_anonymous_struct); 919 920 // C and C++ require different kinds of checks for anonymous 921 // structs/unions. 922 bool Invalid = false; 923 if (getLangOptions().CPlusPlus) { 924 const char* PrevSpec = 0; 925 // C++ [class.union]p3: 926 // Anonymous unions declared in a named namespace or in the 927 // global namespace shall be declared static. 928 if (DS.getStorageClassSpec() != DeclSpec::SCS_static && 929 (isa<TranslationUnitDecl>(Owner) || 930 (isa<NamespaceDecl>(Owner) && 931 cast<NamespaceDecl>(Owner)->getDeclName()))) { 932 Diag(Record->getLocation(), diag::err_anonymous_union_not_static); 933 Invalid = true; 934 935 // Recover by adding 'static'. 936 DS.SetStorageClassSpec(DeclSpec::SCS_static, SourceLocation(), PrevSpec); 937 } 938 // C++ [class.union]p3: 939 // A storage class is not allowed in a declaration of an 940 // anonymous union in a class scope. 941 else if (DS.getStorageClassSpec() != DeclSpec::SCS_unspecified && 942 isa<RecordDecl>(Owner)) { 943 Diag(DS.getStorageClassSpecLoc(), 944 diag::err_anonymous_union_with_storage_spec); 945 Invalid = true; 946 947 // Recover by removing the storage specifier. 948 DS.SetStorageClassSpec(DeclSpec::SCS_unspecified, SourceLocation(), 949 PrevSpec); 950 } 951 952 // C++ [class.union]p2: 953 // The member-specification of an anonymous union shall only 954 // define non-static data members. [Note: nested types and 955 // functions cannot be declared within an anonymous union. ] 956 for (DeclContext::decl_iterator Mem = Record->decls_begin(), 957 MemEnd = Record->decls_end(); 958 Mem != MemEnd; ++Mem) { 959 if (FieldDecl *FD = dyn_cast<FieldDecl>(*Mem)) { 960 // C++ [class.union]p3: 961 // An anonymous union shall not have private or protected 962 // members (clause 11). 963 if (FD->getAccess() == AS_protected || FD->getAccess() == AS_private) { 964 Diag(FD->getLocation(), diag::err_anonymous_record_nonpublic_member) 965 << (int)Record->isUnion() << (int)(FD->getAccess() == AS_protected); 966 Invalid = true; 967 } 968 } else if ((*Mem)->isImplicit()) { 969 // Any implicit members are fine. 970 } else if (RecordDecl *MemRecord = dyn_cast<RecordDecl>(*Mem)) { 971 if (!MemRecord->isAnonymousStructOrUnion() && 972 MemRecord->getDeclName()) { 973 // This is a nested type declaration. 974 Diag(MemRecord->getLocation(), diag::err_anonymous_record_with_type) 975 << (int)Record->isUnion(); 976 Invalid = true; 977 } 978 } else { 979 // We have something that isn't a non-static data 980 // member. Complain about it. 981 unsigned DK = diag::err_anonymous_record_bad_member; 982 if (isa<TypeDecl>(*Mem)) 983 DK = diag::err_anonymous_record_with_type; 984 else if (isa<FunctionDecl>(*Mem)) 985 DK = diag::err_anonymous_record_with_function; 986 else if (isa<VarDecl>(*Mem)) 987 DK = diag::err_anonymous_record_with_static; 988 Diag((*Mem)->getLocation(), DK) 989 << (int)Record->isUnion(); 990 Invalid = true; 991 } 992 } 993 } else { 994 // FIXME: Check GNU C semantics 995 } 996 997 if (!Record->isUnion() && !Owner->isRecord()) { 998 Diag(Record->getLocation(), diag::err_anonymous_struct_not_member); 999 Invalid = true; 1000 } 1001 1002 // Create a declaration for this anonymous struct/union. 1003 ScopedDecl *Anon = 0; 1004 if (RecordDecl *OwningClass = dyn_cast<RecordDecl>(Owner)) { 1005 Anon = FieldDecl::Create(Context, OwningClass, Record->getLocation(), 1006 /*IdentifierInfo=*/0, 1007 Context.getTypeDeclType(Record), 1008 /*BitWidth=*/0, /*Mutable=*/false, 1009 /*PrevDecl=*/0); 1010 Anon->setAccess(AS_public); 1011 if (getLangOptions().CPlusPlus) 1012 FieldCollector->Add(cast<FieldDecl>(Anon)); 1013 } else { 1014 VarDecl::StorageClass SC; 1015 switch (DS.getStorageClassSpec()) { 1016 default: assert(0 && "Unknown storage class!"); 1017 case DeclSpec::SCS_unspecified: SC = VarDecl::None; break; 1018 case DeclSpec::SCS_extern: SC = VarDecl::Extern; break; 1019 case DeclSpec::SCS_static: SC = VarDecl::Static; break; 1020 case DeclSpec::SCS_auto: SC = VarDecl::Auto; break; 1021 case DeclSpec::SCS_register: SC = VarDecl::Register; break; 1022 case DeclSpec::SCS_private_extern: SC = VarDecl::PrivateExtern; break; 1023 case DeclSpec::SCS_mutable: 1024 // mutable can only appear on non-static class members, so it's always 1025 // an error here 1026 Diag(Record->getLocation(), diag::err_mutable_nonmember); 1027 Invalid = true; 1028 SC = VarDecl::None; 1029 break; 1030 } 1031 1032 Anon = VarDecl::Create(Context, Owner, Record->getLocation(), 1033 /*IdentifierInfo=*/0, 1034 Context.getTypeDeclType(Record), 1035 SC, /*FIXME:LastDeclarator=*/0, 1036 DS.getSourceRange().getBegin()); 1037 } 1038 Anon->setImplicit(); 1039 1040 // Add the anonymous struct/union object to the current 1041 // context. We'll be referencing this object when we refer to one of 1042 // its members. 1043 Owner->addDecl(Context, Anon); 1044 1045 // Inject the members of the anonymous struct/union into the owning 1046 // context and into the identifier resolver chain for name lookup 1047 // purposes. 1048 Invalid = Invalid || InjectAnonymousStructOrUnionMembers(S, Owner, Record); 1049 1050 // Mark this as an anonymous struct/union type. Note that we do not 1051 // do this until after we have already checked and injected the 1052 // members of this anonymous struct/union type, because otherwise 1053 // the members could be injected twice: once by DeclContext when it 1054 // builds its lookup table, and once by 1055 // InjectAnonymousStructOrUnionMembers. 1056 Record->setAnonymousStructOrUnion(true); 1057 1058 if (Invalid) 1059 Anon->setInvalidDecl(); 1060 1061 return Anon; 1062} 1063 1064bool Sema::CheckSingleInitializer(Expr *&Init, QualType DeclType) { 1065 // Get the type before calling CheckSingleAssignmentConstraints(), since 1066 // it can promote the expression. 1067 QualType InitType = Init->getType(); 1068 1069 if (getLangOptions().CPlusPlus) 1070 return PerformCopyInitialization(Init, DeclType, "initializing"); 1071 1072 AssignConvertType ConvTy = CheckSingleAssignmentConstraints(DeclType, Init); 1073 return DiagnoseAssignmentResult(ConvTy, Init->getLocStart(), DeclType, 1074 InitType, Init, "initializing"); 1075} 1076 1077bool Sema::CheckStringLiteralInit(StringLiteral *strLiteral, QualType &DeclT) { 1078 const ArrayType *AT = Context.getAsArrayType(DeclT); 1079 1080 if (const IncompleteArrayType *IAT = dyn_cast<IncompleteArrayType>(AT)) { 1081 // C99 6.7.8p14. We have an array of character type with unknown size 1082 // being initialized to a string literal. 1083 llvm::APSInt ConstVal(32); 1084 ConstVal = strLiteral->getByteLength() + 1; 1085 // Return a new array type (C99 6.7.8p22). 1086 DeclT = Context.getConstantArrayType(IAT->getElementType(), ConstVal, 1087 ArrayType::Normal, 0); 1088 } else { 1089 const ConstantArrayType *CAT = cast<ConstantArrayType>(AT); 1090 // C99 6.7.8p14. We have an array of character type with known size. 1091 // FIXME: Avoid truncation for 64-bit length strings. 1092 if (strLiteral->getByteLength() > (unsigned)CAT->getSize().getZExtValue()) 1093 Diag(strLiteral->getSourceRange().getBegin(), 1094 diag::warn_initializer_string_for_char_array_too_long) 1095 << strLiteral->getSourceRange(); 1096 } 1097 // Set type from "char *" to "constant array of char". 1098 strLiteral->setType(DeclT); 1099 // For now, we always return false (meaning success). 1100 return false; 1101} 1102 1103StringLiteral *Sema::IsStringLiteralInit(Expr *Init, QualType DeclType) { 1104 const ArrayType *AT = Context.getAsArrayType(DeclType); 1105 if (AT && AT->getElementType()->isCharType()) { 1106 return dyn_cast<StringLiteral>(Init); 1107 } 1108 return 0; 1109} 1110 1111bool Sema::CheckInitializerTypes(Expr *&Init, QualType &DeclType, 1112 SourceLocation InitLoc, 1113 DeclarationName InitEntity) { 1114 if (DeclType->isDependentType() || Init->isTypeDependent()) 1115 return false; 1116 1117 // C++ [dcl.init.ref]p1: 1118 // A variable declared to be a T&, that is "reference to type T" 1119 // (8.3.2), shall be initialized by an object, or function, of 1120 // type T or by an object that can be converted into a T. 1121 if (DeclType->isReferenceType()) 1122 return CheckReferenceInit(Init, DeclType); 1123 1124 // C99 6.7.8p3: The type of the entity to be initialized shall be an array 1125 // of unknown size ("[]") or an object type that is not a variable array type. 1126 if (const VariableArrayType *VAT = Context.getAsVariableArrayType(DeclType)) 1127 return Diag(InitLoc, diag::err_variable_object_no_init) 1128 << VAT->getSizeExpr()->getSourceRange(); 1129 1130 InitListExpr *InitList = dyn_cast<InitListExpr>(Init); 1131 if (!InitList) { 1132 // FIXME: Handle wide strings 1133 if (StringLiteral *strLiteral = IsStringLiteralInit(Init, DeclType)) 1134 return CheckStringLiteralInit(strLiteral, DeclType); 1135 1136 // C++ [dcl.init]p14: 1137 // -- If the destination type is a (possibly cv-qualified) class 1138 // type: 1139 if (getLangOptions().CPlusPlus && DeclType->isRecordType()) { 1140 QualType DeclTypeC = Context.getCanonicalType(DeclType); 1141 QualType InitTypeC = Context.getCanonicalType(Init->getType()); 1142 1143 // -- If the initialization is direct-initialization, or if it is 1144 // copy-initialization where the cv-unqualified version of the 1145 // source type is the same class as, or a derived class of, the 1146 // class of the destination, constructors are considered. 1147 if ((DeclTypeC.getUnqualifiedType() == InitTypeC.getUnqualifiedType()) || 1148 IsDerivedFrom(InitTypeC, DeclTypeC)) { 1149 CXXConstructorDecl *Constructor 1150 = PerformInitializationByConstructor(DeclType, &Init, 1, 1151 InitLoc, Init->getSourceRange(), 1152 InitEntity, IK_Copy); 1153 return Constructor == 0; 1154 } 1155 1156 // -- Otherwise (i.e., for the remaining copy-initialization 1157 // cases), user-defined conversion sequences that can 1158 // convert from the source type to the destination type or 1159 // (when a conversion function is used) to a derived class 1160 // thereof are enumerated as described in 13.3.1.4, and the 1161 // best one is chosen through overload resolution 1162 // (13.3). If the conversion cannot be done or is 1163 // ambiguous, the initialization is ill-formed. The 1164 // function selected is called with the initializer 1165 // expression as its argument; if the function is a 1166 // constructor, the call initializes a temporary of the 1167 // destination type. 1168 // FIXME: We're pretending to do copy elision here; return to 1169 // this when we have ASTs for such things. 1170 if (!PerformImplicitConversion(Init, DeclType, "initializing")) 1171 return false; 1172 1173 if (InitEntity) 1174 return Diag(InitLoc, diag::err_cannot_initialize_decl) 1175 << InitEntity << (int)(Init->isLvalue(Context) == Expr::LV_Valid) 1176 << Init->getType() << Init->getSourceRange(); 1177 else 1178 return Diag(InitLoc, diag::err_cannot_initialize_decl_noname) 1179 << DeclType << (int)(Init->isLvalue(Context) == Expr::LV_Valid) 1180 << Init->getType() << Init->getSourceRange(); 1181 } 1182 1183 // C99 6.7.8p16. 1184 if (DeclType->isArrayType()) 1185 return Diag(Init->getLocStart(), diag::err_array_init_list_required) 1186 << Init->getSourceRange(); 1187 1188 return CheckSingleInitializer(Init, DeclType); 1189 } else if (getLangOptions().CPlusPlus) { 1190 // C++ [dcl.init]p14: 1191 // [...] If the class is an aggregate (8.5.1), and the initializer 1192 // is a brace-enclosed list, see 8.5.1. 1193 // 1194 // Note: 8.5.1 is handled below; here, we diagnose the case where 1195 // we have an initializer list and a destination type that is not 1196 // an aggregate. 1197 // FIXME: In C++0x, this is yet another form of initialization. 1198 if (const RecordType *ClassRec = DeclType->getAsRecordType()) { 1199 const CXXRecordDecl *ClassDecl = cast<CXXRecordDecl>(ClassRec->getDecl()); 1200 if (!ClassDecl->isAggregate()) 1201 return Diag(InitLoc, diag::err_init_non_aggr_init_list) 1202 << DeclType << Init->getSourceRange(); 1203 } 1204 } 1205 1206 InitListChecker CheckInitList(this, InitList, DeclType); 1207 return CheckInitList.HadError(); 1208} 1209 1210/// GetNameForDeclarator - Determine the full declaration name for the 1211/// given Declarator. 1212DeclarationName Sema::GetNameForDeclarator(Declarator &D) { 1213 switch (D.getKind()) { 1214 case Declarator::DK_Abstract: 1215 assert(D.getIdentifier() == 0 && "abstract declarators have no name"); 1216 return DeclarationName(); 1217 1218 case Declarator::DK_Normal: 1219 assert (D.getIdentifier() != 0 && "normal declarators have an identifier"); 1220 return DeclarationName(D.getIdentifier()); 1221 1222 case Declarator::DK_Constructor: { 1223 QualType Ty = Context.getTypeDeclType((TypeDecl *)D.getDeclaratorIdType()); 1224 Ty = Context.getCanonicalType(Ty); 1225 return Context.DeclarationNames.getCXXConstructorName(Ty); 1226 } 1227 1228 case Declarator::DK_Destructor: { 1229 QualType Ty = Context.getTypeDeclType((TypeDecl *)D.getDeclaratorIdType()); 1230 Ty = Context.getCanonicalType(Ty); 1231 return Context.DeclarationNames.getCXXDestructorName(Ty); 1232 } 1233 1234 case Declarator::DK_Conversion: { 1235 QualType Ty = QualType::getFromOpaquePtr(D.getDeclaratorIdType()); 1236 Ty = Context.getCanonicalType(Ty); 1237 return Context.DeclarationNames.getCXXConversionFunctionName(Ty); 1238 } 1239 1240 case Declarator::DK_Operator: 1241 assert(D.getIdentifier() == 0 && "operator names have no identifier"); 1242 return Context.DeclarationNames.getCXXOperatorName( 1243 D.getOverloadedOperator()); 1244 } 1245 1246 assert(false && "Unknown name kind"); 1247 return DeclarationName(); 1248} 1249 1250/// isNearlyMatchingMemberFunction - Determine whether the C++ member 1251/// functions Declaration and Definition are "nearly" matching. This 1252/// heuristic is used to improve diagnostics in the case where an 1253/// out-of-line member function definition doesn't match any 1254/// declaration within the class. 1255static bool isNearlyMatchingMemberFunction(ASTContext &Context, 1256 FunctionDecl *Declaration, 1257 FunctionDecl *Definition) { 1258 if (Declaration->param_size() != Definition->param_size()) 1259 return false; 1260 for (unsigned Idx = 0; Idx < Declaration->param_size(); ++Idx) { 1261 QualType DeclParamTy = Declaration->getParamDecl(Idx)->getType(); 1262 QualType DefParamTy = Definition->getParamDecl(Idx)->getType(); 1263 1264 DeclParamTy = Context.getCanonicalType(DeclParamTy.getNonReferenceType()); 1265 DefParamTy = Context.getCanonicalType(DefParamTy.getNonReferenceType()); 1266 if (DeclParamTy.getUnqualifiedType() != DefParamTy.getUnqualifiedType()) 1267 return false; 1268 } 1269 1270 return true; 1271} 1272 1273Sema::DeclTy * 1274Sema::ActOnDeclarator(Scope *S, Declarator &D, DeclTy *lastDecl, 1275 bool IsFunctionDefinition) { 1276 ScopedDecl *LastDeclarator = dyn_cast_or_null<ScopedDecl>((Decl *)lastDecl); 1277 DeclarationName Name = GetNameForDeclarator(D); 1278 1279 // All of these full declarators require an identifier. If it doesn't have 1280 // one, the ParsedFreeStandingDeclSpec action should be used. 1281 if (!Name) { 1282 if (!D.getInvalidType()) // Reject this if we think it is valid. 1283 Diag(D.getDeclSpec().getSourceRange().getBegin(), 1284 diag::err_declarator_need_ident) 1285 << D.getDeclSpec().getSourceRange() << D.getSourceRange(); 1286 return 0; 1287 } 1288 1289 // The scope passed in may not be a decl scope. Zip up the scope tree until 1290 // we find one that is. 1291 while ((S->getFlags() & Scope::DeclScope) == 0 || 1292 (S->getFlags() & Scope::TemplateParamScope) != 0) 1293 S = S->getParent(); 1294 1295 DeclContext *DC; 1296 Decl *PrevDecl; 1297 ScopedDecl *New; 1298 bool InvalidDecl = false; 1299 1300 // See if this is a redefinition of a variable in the same scope. 1301 if (!D.getCXXScopeSpec().isSet()) { 1302 DC = CurContext; 1303 PrevDecl = LookupDecl(Name, Decl::IDNS_Ordinary, S); 1304 } else { // Something like "int foo::x;" 1305 DC = static_cast<DeclContext*>(D.getCXXScopeSpec().getScopeRep()); 1306 PrevDecl = LookupDecl(Name, Decl::IDNS_Ordinary, S, DC); 1307 1308 // C++ 7.3.1.2p2: 1309 // Members (including explicit specializations of templates) of a named 1310 // namespace can also be defined outside that namespace by explicit 1311 // qualification of the name being defined, provided that the entity being 1312 // defined was already declared in the namespace and the definition appears 1313 // after the point of declaration in a namespace that encloses the 1314 // declarations namespace. 1315 // 1316 // Note that we only check the context at this point. We don't yet 1317 // have enough information to make sure that PrevDecl is actually 1318 // the declaration we want to match. For example, given: 1319 // 1320 // class X { 1321 // void f(); 1322 // void f(float); 1323 // }; 1324 // 1325 // void X::f(int) { } // ill-formed 1326 // 1327 // In this case, PrevDecl will point to the overload set 1328 // containing the two f's declared in X, but neither of them 1329 // matches. 1330 if (!CurContext->Encloses(DC)) { 1331 // The qualifying scope doesn't enclose the original declaration. 1332 // Emit diagnostic based on current scope. 1333 SourceLocation L = D.getIdentifierLoc(); 1334 SourceRange R = D.getCXXScopeSpec().getRange(); 1335 if (isa<FunctionDecl>(CurContext)) { 1336 Diag(L, diag::err_invalid_declarator_in_function) << Name << R; 1337 } else { 1338 Diag(L, diag::err_invalid_declarator_scope) 1339 << Name << cast<NamedDecl>(DC)->getDeclName() << R; 1340 } 1341 InvalidDecl = true; 1342 } 1343 } 1344 1345 if (PrevDecl && PrevDecl->isTemplateParameter()) { 1346 // Maybe we will complain about the shadowed template parameter. 1347 InvalidDecl = InvalidDecl 1348 || DiagnoseTemplateParameterShadow(D.getIdentifierLoc(), PrevDecl); 1349 // Just pretend that we didn't see the previous declaration. 1350 PrevDecl = 0; 1351 } 1352 1353 // In C++, the previous declaration we find might be a tag type 1354 // (class or enum). In this case, the new declaration will hide the 1355 // tag type. 1356 if (PrevDecl && PrevDecl->getIdentifierNamespace() == Decl::IDNS_Tag) 1357 PrevDecl = 0; 1358 1359 QualType R = GetTypeForDeclarator(D, S); 1360 assert(!R.isNull() && "GetTypeForDeclarator() returned null type"); 1361 1362 if (D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_typedef) { 1363 // Typedef declarators cannot be qualified (C++ [dcl.meaning]p1). 1364 if (D.getCXXScopeSpec().isSet()) { 1365 Diag(D.getIdentifierLoc(), diag::err_qualified_typedef_declarator) 1366 << D.getCXXScopeSpec().getRange(); 1367 InvalidDecl = true; 1368 // Pretend we didn't see the scope specifier. 1369 DC = 0; 1370 } 1371 1372 // Check that there are no default arguments (C++ only). 1373 if (getLangOptions().CPlusPlus) 1374 CheckExtraCXXDefaultArguments(D); 1375 1376 TypedefDecl *NewTD = ParseTypedefDecl(S, D, R, LastDeclarator); 1377 if (!NewTD) return 0; 1378 1379 // Handle attributes prior to checking for duplicates in MergeVarDecl 1380 ProcessDeclAttributes(NewTD, D); 1381 // Merge the decl with the existing one if appropriate. If the decl is 1382 // in an outer scope, it isn't the same thing. 1383 if (PrevDecl && isDeclInScope(PrevDecl, DC, S)) { 1384 NewTD = MergeTypeDefDecl(NewTD, PrevDecl); 1385 if (NewTD == 0) return 0; 1386 } 1387 New = NewTD; 1388 if (S->getFnParent() == 0) { 1389 // C99 6.7.7p2: If a typedef name specifies a variably modified type 1390 // then it shall have block scope. 1391 if (NewTD->getUnderlyingType()->isVariablyModifiedType()) { 1392 if (NewTD->getUnderlyingType()->isVariableArrayType()) 1393 Diag(D.getIdentifierLoc(), diag::err_vla_decl_in_file_scope); 1394 else 1395 Diag(D.getIdentifierLoc(), diag::err_vm_decl_in_file_scope); 1396 1397 InvalidDecl = true; 1398 } 1399 } 1400 } else if (R.getTypePtr()->isFunctionType()) { 1401 FunctionDecl::StorageClass SC = FunctionDecl::None; 1402 switch (D.getDeclSpec().getStorageClassSpec()) { 1403 default: assert(0 && "Unknown storage class!"); 1404 case DeclSpec::SCS_auto: 1405 case DeclSpec::SCS_register: 1406 case DeclSpec::SCS_mutable: 1407 Diag(D.getIdentifierLoc(), diag::err_typecheck_sclass_func); 1408 InvalidDecl = true; 1409 break; 1410 case DeclSpec::SCS_unspecified: SC = FunctionDecl::None; break; 1411 case DeclSpec::SCS_extern: SC = FunctionDecl::Extern; break; 1412 case DeclSpec::SCS_static: SC = FunctionDecl::Static; break; 1413 case DeclSpec::SCS_private_extern: SC = FunctionDecl::PrivateExtern;break; 1414 } 1415 1416 bool isInline = D.getDeclSpec().isInlineSpecified(); 1417 // bool isVirtual = D.getDeclSpec().isVirtualSpecified(); 1418 bool isExplicit = D.getDeclSpec().isExplicitSpecified(); 1419 1420 FunctionDecl *NewFD; 1421 if (D.getKind() == Declarator::DK_Constructor) { 1422 // This is a C++ constructor declaration. 1423 assert(DC->isRecord() && 1424 "Constructors can only be declared in a member context"); 1425 1426 InvalidDecl = InvalidDecl || CheckConstructorDeclarator(D, R, SC); 1427 1428 // Create the new declaration 1429 NewFD = CXXConstructorDecl::Create(Context, 1430 cast<CXXRecordDecl>(DC), 1431 D.getIdentifierLoc(), Name, R, 1432 isExplicit, isInline, 1433 /*isImplicitlyDeclared=*/false); 1434 1435 if (InvalidDecl) 1436 NewFD->setInvalidDecl(); 1437 } else if (D.getKind() == Declarator::DK_Destructor) { 1438 // This is a C++ destructor declaration. 1439 if (DC->isRecord()) { 1440 InvalidDecl = InvalidDecl || CheckDestructorDeclarator(D, R, SC); 1441 1442 NewFD = CXXDestructorDecl::Create(Context, 1443 cast<CXXRecordDecl>(DC), 1444 D.getIdentifierLoc(), Name, R, 1445 isInline, 1446 /*isImplicitlyDeclared=*/false); 1447 1448 if (InvalidDecl) 1449 NewFD->setInvalidDecl(); 1450 } else { 1451 Diag(D.getIdentifierLoc(), diag::err_destructor_not_member); 1452 1453 // Create a FunctionDecl to satisfy the function definition parsing 1454 // code path. 1455 NewFD = FunctionDecl::Create(Context, DC, D.getIdentifierLoc(), 1456 Name, R, SC, isInline, LastDeclarator, 1457 // FIXME: Move to DeclGroup... 1458 D.getDeclSpec().getSourceRange().getBegin()); 1459 InvalidDecl = true; 1460 NewFD->setInvalidDecl(); 1461 } 1462 } else if (D.getKind() == Declarator::DK_Conversion) { 1463 if (!DC->isRecord()) { 1464 Diag(D.getIdentifierLoc(), 1465 diag::err_conv_function_not_member); 1466 return 0; 1467 } else { 1468 InvalidDecl = InvalidDecl || CheckConversionDeclarator(D, R, SC); 1469 1470 NewFD = CXXConversionDecl::Create(Context, cast<CXXRecordDecl>(DC), 1471 D.getIdentifierLoc(), Name, R, 1472 isInline, isExplicit); 1473 1474 if (InvalidDecl) 1475 NewFD->setInvalidDecl(); 1476 } 1477 } else if (DC->isRecord()) { 1478 // This is a C++ method declaration. 1479 NewFD = CXXMethodDecl::Create(Context, cast<CXXRecordDecl>(DC), 1480 D.getIdentifierLoc(), Name, R, 1481 (SC == FunctionDecl::Static), isInline, 1482 LastDeclarator); 1483 } else { 1484 NewFD = FunctionDecl::Create(Context, DC, 1485 D.getIdentifierLoc(), 1486 Name, R, SC, isInline, LastDeclarator, 1487 // FIXME: Move to DeclGroup... 1488 D.getDeclSpec().getSourceRange().getBegin()); 1489 } 1490 1491 // Set the lexical context. If the declarator has a C++ 1492 // scope specifier, the lexical context will be different 1493 // from the semantic context. 1494 NewFD->setLexicalDeclContext(CurContext); 1495 1496 // Handle GNU asm-label extension (encoded as an attribute). 1497 if (Expr *E = (Expr*) D.getAsmLabel()) { 1498 // The parser guarantees this is a string. 1499 StringLiteral *SE = cast<StringLiteral>(E); 1500 NewFD->addAttr(new AsmLabelAttr(std::string(SE->getStrData(), 1501 SE->getByteLength()))); 1502 } 1503 1504 // Copy the parameter declarations from the declarator D to 1505 // the function declaration NewFD, if they are available. 1506 if (D.getNumTypeObjects() > 0) { 1507 DeclaratorChunk::FunctionTypeInfo &FTI = D.getTypeObject(0).Fun; 1508 1509 // Create Decl objects for each parameter, adding them to the 1510 // FunctionDecl. 1511 llvm::SmallVector<ParmVarDecl*, 16> Params; 1512 1513 // Check for C99 6.7.5.3p10 - foo(void) is a non-varargs 1514 // function that takes no arguments, not a function that takes a 1515 // single void argument. 1516 // We let through "const void" here because Sema::GetTypeForDeclarator 1517 // already checks for that case. 1518 if (FTI.NumArgs == 1 && !FTI.isVariadic && FTI.ArgInfo[0].Ident == 0 && 1519 FTI.ArgInfo[0].Param && 1520 ((ParmVarDecl*)FTI.ArgInfo[0].Param)->getType()->isVoidType()) { 1521 // empty arg list, don't push any params. 1522 ParmVarDecl *Param = (ParmVarDecl*)FTI.ArgInfo[0].Param; 1523 1524 // In C++, the empty parameter-type-list must be spelled "void"; a 1525 // typedef of void is not permitted. 1526 if (getLangOptions().CPlusPlus && 1527 Param->getType().getUnqualifiedType() != Context.VoidTy) { 1528 Diag(Param->getLocation(), diag::ext_param_typedef_of_void); 1529 } 1530 } else if (FTI.NumArgs > 0 && FTI.ArgInfo[0].Param != 0) { 1531 for (unsigned i = 0, e = FTI.NumArgs; i != e; ++i) 1532 Params.push_back((ParmVarDecl *)FTI.ArgInfo[i].Param); 1533 } 1534 1535 NewFD->setParams(&Params[0], Params.size()); 1536 } else if (R->getAsTypedefType()) { 1537 // When we're declaring a function with a typedef, as in the 1538 // following example, we'll need to synthesize (unnamed) 1539 // parameters for use in the declaration. 1540 // 1541 // @code 1542 // typedef void fn(int); 1543 // fn f; 1544 // @endcode 1545 const FunctionTypeProto *FT = R->getAsFunctionTypeProto(); 1546 if (!FT) { 1547 // This is a typedef of a function with no prototype, so we 1548 // don't need to do anything. 1549 } else if ((FT->getNumArgs() == 0) || 1550 (FT->getNumArgs() == 1 && !FT->isVariadic() && 1551 FT->getArgType(0)->isVoidType())) { 1552 // This is a zero-argument function. We don't need to do anything. 1553 } else { 1554 // Synthesize a parameter for each argument type. 1555 llvm::SmallVector<ParmVarDecl*, 16> Params; 1556 for (FunctionTypeProto::arg_type_iterator ArgType = FT->arg_type_begin(); 1557 ArgType != FT->arg_type_end(); ++ArgType) { 1558 Params.push_back(ParmVarDecl::Create(Context, DC, 1559 SourceLocation(), 0, 1560 *ArgType, VarDecl::None, 1561 0, 0)); 1562 } 1563 1564 NewFD->setParams(&Params[0], Params.size()); 1565 } 1566 } 1567 1568 if (CXXConstructorDecl *Constructor = dyn_cast<CXXConstructorDecl>(NewFD)) 1569 InvalidDecl = InvalidDecl || CheckConstructor(Constructor); 1570 else if (isa<CXXDestructorDecl>(NewFD)) { 1571 CXXRecordDecl *Record = cast<CXXRecordDecl>(NewFD->getParent()); 1572 Record->setUserDeclaredDestructor(true); 1573 // C++ [class]p4: A POD-struct is an aggregate class that has [...] no 1574 // user-defined destructor. 1575 Record->setPOD(false); 1576 } else if (CXXConversionDecl *Conversion = 1577 dyn_cast<CXXConversionDecl>(NewFD)) 1578 ActOnConversionDeclarator(Conversion); 1579 1580 // Extra checking for C++ overloaded operators (C++ [over.oper]). 1581 if (NewFD->isOverloadedOperator() && 1582 CheckOverloadedOperatorDeclaration(NewFD)) 1583 NewFD->setInvalidDecl(); 1584 1585 // Merge the decl with the existing one if appropriate. Since C functions 1586 // are in a flat namespace, make sure we consider decls in outer scopes. 1587 if (PrevDecl && 1588 (!getLangOptions().CPlusPlus||isDeclInScope(PrevDecl, DC, S))) { 1589 bool Redeclaration = false; 1590 1591 // If C++, determine whether NewFD is an overload of PrevDecl or 1592 // a declaration that requires merging. If it's an overload, 1593 // there's no more work to do here; we'll just add the new 1594 // function to the scope. 1595 OverloadedFunctionDecl::function_iterator MatchedDecl; 1596 if (!getLangOptions().CPlusPlus || 1597 !IsOverload(NewFD, PrevDecl, MatchedDecl)) { 1598 Decl *OldDecl = PrevDecl; 1599 1600 // If PrevDecl was an overloaded function, extract the 1601 // FunctionDecl that matched. 1602 if (isa<OverloadedFunctionDecl>(PrevDecl)) 1603 OldDecl = *MatchedDecl; 1604 1605 // NewFD and PrevDecl represent declarations that need to be 1606 // merged. 1607 NewFD = MergeFunctionDecl(NewFD, OldDecl, Redeclaration); 1608 1609 if (NewFD == 0) return 0; 1610 if (Redeclaration) { 1611 NewFD->setPreviousDeclaration(cast<FunctionDecl>(OldDecl)); 1612 1613 // An out-of-line member function declaration must also be a 1614 // definition (C++ [dcl.meaning]p1). 1615 if (!IsFunctionDefinition && D.getCXXScopeSpec().isSet() && 1616 !InvalidDecl) { 1617 Diag(NewFD->getLocation(), diag::err_out_of_line_declaration) 1618 << D.getCXXScopeSpec().getRange(); 1619 NewFD->setInvalidDecl(); 1620 } 1621 } 1622 } 1623 1624 if (!Redeclaration && D.getCXXScopeSpec().isSet()) { 1625 // The user tried to provide an out-of-line definition for a 1626 // member function, but there was no such member function 1627 // declared (C++ [class.mfct]p2). For example: 1628 // 1629 // class X { 1630 // void f() const; 1631 // }; 1632 // 1633 // void X::f() { } // ill-formed 1634 // 1635 // Complain about this problem, and attempt to suggest close 1636 // matches (e.g., those that differ only in cv-qualifiers and 1637 // whether the parameter types are references). 1638 Diag(D.getIdentifierLoc(), diag::err_member_def_does_not_match) 1639 << cast<CXXRecordDecl>(DC)->getDeclName() 1640 << D.getCXXScopeSpec().getRange(); 1641 InvalidDecl = true; 1642 1643 PrevDecl = LookupDecl(Name, Decl::IDNS_Ordinary, S, DC); 1644 if (!PrevDecl) { 1645 // Nothing to suggest. 1646 } else if (OverloadedFunctionDecl *Ovl 1647 = dyn_cast<OverloadedFunctionDecl>(PrevDecl)) { 1648 for (OverloadedFunctionDecl::function_iterator 1649 Func = Ovl->function_begin(), 1650 FuncEnd = Ovl->function_end(); 1651 Func != FuncEnd; ++Func) { 1652 if (isNearlyMatchingMemberFunction(Context, *Func, NewFD)) 1653 Diag((*Func)->getLocation(), diag::note_member_def_close_match); 1654 1655 } 1656 } else if (CXXMethodDecl *Method = dyn_cast<CXXMethodDecl>(PrevDecl)) { 1657 // Suggest this no matter how mismatched it is; it's the only 1658 // thing we have. 1659 unsigned diag; 1660 if (isNearlyMatchingMemberFunction(Context, Method, NewFD)) 1661 diag = diag::note_member_def_close_match; 1662 else if (Method->getBody()) 1663 diag = diag::note_previous_definition; 1664 else 1665 diag = diag::note_previous_declaration; 1666 Diag(Method->getLocation(), diag); 1667 } 1668 1669 PrevDecl = 0; 1670 } 1671 } 1672 // Handle attributes. We need to have merged decls when handling attributes 1673 // (for example to check for conflicts, etc). 1674 ProcessDeclAttributes(NewFD, D); 1675 New = NewFD; 1676 1677 if (getLangOptions().CPlusPlus) { 1678 // In C++, check default arguments now that we have merged decls. 1679 CheckCXXDefaultArguments(NewFD); 1680 1681 // An out-of-line member function declaration must also be a 1682 // definition (C++ [dcl.meaning]p1). 1683 if (!IsFunctionDefinition && D.getCXXScopeSpec().isSet() && !InvalidDecl) { 1684 Diag(NewFD->getLocation(), diag::err_out_of_line_declaration) 1685 << D.getCXXScopeSpec().getRange(); 1686 InvalidDecl = true; 1687 } 1688 } 1689 } else { 1690 // Check that there are no default arguments (C++ only). 1691 if (getLangOptions().CPlusPlus) 1692 CheckExtraCXXDefaultArguments(D); 1693 1694 if (R.getTypePtr()->isObjCInterfaceType()) { 1695 Diag(D.getIdentifierLoc(), diag::err_statically_allocated_object) 1696 << D.getIdentifier(); 1697 InvalidDecl = true; 1698 } 1699 1700 VarDecl *NewVD; 1701 VarDecl::StorageClass SC; 1702 switch (D.getDeclSpec().getStorageClassSpec()) { 1703 default: assert(0 && "Unknown storage class!"); 1704 case DeclSpec::SCS_unspecified: SC = VarDecl::None; break; 1705 case DeclSpec::SCS_extern: SC = VarDecl::Extern; break; 1706 case DeclSpec::SCS_static: SC = VarDecl::Static; break; 1707 case DeclSpec::SCS_auto: SC = VarDecl::Auto; break; 1708 case DeclSpec::SCS_register: SC = VarDecl::Register; break; 1709 case DeclSpec::SCS_private_extern: SC = VarDecl::PrivateExtern; break; 1710 case DeclSpec::SCS_mutable: 1711 // mutable can only appear on non-static class members, so it's always 1712 // an error here 1713 Diag(D.getIdentifierLoc(), diag::err_mutable_nonmember); 1714 InvalidDecl = true; 1715 SC = VarDecl::None; 1716 break; 1717 } 1718 1719 IdentifierInfo *II = Name.getAsIdentifierInfo(); 1720 if (!II) { 1721 Diag(D.getIdentifierLoc(), diag::err_bad_variable_name) 1722 << Name.getAsString(); 1723 return 0; 1724 } 1725 1726 if (DC->isRecord()) { 1727 // This is a static data member for a C++ class. 1728 NewVD = CXXClassVarDecl::Create(Context, cast<CXXRecordDecl>(DC), 1729 D.getIdentifierLoc(), II, 1730 R, LastDeclarator); 1731 } else { 1732 bool ThreadSpecified = D.getDeclSpec().isThreadSpecified(); 1733 if (S->getFnParent() == 0) { 1734 // C99 6.9p2: The storage-class specifiers auto and register shall not 1735 // appear in the declaration specifiers in an external declaration. 1736 if (SC == VarDecl::Auto || SC == VarDecl::Register) { 1737 Diag(D.getIdentifierLoc(), diag::err_typecheck_sclass_fscope); 1738 InvalidDecl = true; 1739 } 1740 } 1741 NewVD = VarDecl::Create(Context, DC, D.getIdentifierLoc(), 1742 II, R, SC, LastDeclarator, 1743 // FIXME: Move to DeclGroup... 1744 D.getDeclSpec().getSourceRange().getBegin()); 1745 NewVD->setThreadSpecified(ThreadSpecified); 1746 } 1747 // Handle attributes prior to checking for duplicates in MergeVarDecl 1748 ProcessDeclAttributes(NewVD, D); 1749 1750 // Handle GNU asm-label extension (encoded as an attribute). 1751 if (Expr *E = (Expr*) D.getAsmLabel()) { 1752 // The parser guarantees this is a string. 1753 StringLiteral *SE = cast<StringLiteral>(E); 1754 NewVD->addAttr(new AsmLabelAttr(std::string(SE->getStrData(), 1755 SE->getByteLength()))); 1756 } 1757 1758 // Emit an error if an address space was applied to decl with local storage. 1759 // This includes arrays of objects with address space qualifiers, but not 1760 // automatic variables that point to other address spaces. 1761 // ISO/IEC TR 18037 S5.1.2 1762 if (NewVD->hasLocalStorage() && (NewVD->getType().getAddressSpace() != 0)) { 1763 Diag(D.getIdentifierLoc(), diag::err_as_qualified_auto_decl); 1764 InvalidDecl = true; 1765 } 1766 // Merge the decl with the existing one if appropriate. If the decl is 1767 // in an outer scope, it isn't the same thing. 1768 if (PrevDecl && isDeclInScope(PrevDecl, DC, S)) { 1769 if (isa<FieldDecl>(PrevDecl) && D.getCXXScopeSpec().isSet()) { 1770 // The user tried to define a non-static data member 1771 // out-of-line (C++ [dcl.meaning]p1). 1772 Diag(NewVD->getLocation(), diag::err_nonstatic_member_out_of_line) 1773 << D.getCXXScopeSpec().getRange(); 1774 NewVD->Destroy(Context); 1775 return 0; 1776 } 1777 1778 NewVD = MergeVarDecl(NewVD, PrevDecl); 1779 if (NewVD == 0) return 0; 1780 1781 if (D.getCXXScopeSpec().isSet()) { 1782 // No previous declaration in the qualifying scope. 1783 Diag(D.getIdentifierLoc(), diag::err_typecheck_no_member) 1784 << Name << D.getCXXScopeSpec().getRange(); 1785 InvalidDecl = true; 1786 } 1787 } 1788 New = NewVD; 1789 } 1790 1791 // Set the lexical context. If the declarator has a C++ scope specifier, the 1792 // lexical context will be different from the semantic context. 1793 New->setLexicalDeclContext(CurContext); 1794 1795 // If this has an identifier, add it to the scope stack. 1796 if (Name) 1797 PushOnScopeChains(New, S); 1798 // If any semantic error occurred, mark the decl as invalid. 1799 if (D.getInvalidType() || InvalidDecl) 1800 New->setInvalidDecl(); 1801 1802 return New; 1803} 1804 1805void Sema::InitializerElementNotConstant(const Expr *Init) { 1806 Diag(Init->getExprLoc(), diag::err_init_element_not_constant) 1807 << Init->getSourceRange(); 1808} 1809 1810bool Sema::CheckAddressConstantExpressionLValue(const Expr* Init) { 1811 switch (Init->getStmtClass()) { 1812 default: 1813 InitializerElementNotConstant(Init); 1814 return true; 1815 case Expr::ParenExprClass: { 1816 const ParenExpr* PE = cast<ParenExpr>(Init); 1817 return CheckAddressConstantExpressionLValue(PE->getSubExpr()); 1818 } 1819 case Expr::CompoundLiteralExprClass: 1820 return cast<CompoundLiteralExpr>(Init)->isFileScope(); 1821 case Expr::DeclRefExprClass: 1822 case Expr::QualifiedDeclRefExprClass: { 1823 const Decl *D = cast<DeclRefExpr>(Init)->getDecl(); 1824 if (const VarDecl *VD = dyn_cast<VarDecl>(D)) { 1825 if (VD->hasGlobalStorage()) 1826 return false; 1827 InitializerElementNotConstant(Init); 1828 return true; 1829 } 1830 if (isa<FunctionDecl>(D)) 1831 return false; 1832 InitializerElementNotConstant(Init); 1833 return true; 1834 } 1835 case Expr::MemberExprClass: { 1836 const MemberExpr *M = cast<MemberExpr>(Init); 1837 if (M->isArrow()) 1838 return CheckAddressConstantExpression(M->getBase()); 1839 return CheckAddressConstantExpressionLValue(M->getBase()); 1840 } 1841 case Expr::ArraySubscriptExprClass: { 1842 // FIXME: Should we pedwarn for "x[0+0]" (where x is a pointer)? 1843 const ArraySubscriptExpr *ASE = cast<ArraySubscriptExpr>(Init); 1844 return CheckAddressConstantExpression(ASE->getBase()) || 1845 CheckArithmeticConstantExpression(ASE->getIdx()); 1846 } 1847 case Expr::StringLiteralClass: 1848 case Expr::PredefinedExprClass: 1849 return false; 1850 case Expr::UnaryOperatorClass: { 1851 const UnaryOperator *Exp = cast<UnaryOperator>(Init); 1852 1853 // C99 6.6p9 1854 if (Exp->getOpcode() == UnaryOperator::Deref) 1855 return CheckAddressConstantExpression(Exp->getSubExpr()); 1856 1857 InitializerElementNotConstant(Init); 1858 return true; 1859 } 1860 } 1861} 1862 1863bool Sema::CheckAddressConstantExpression(const Expr* Init) { 1864 switch (Init->getStmtClass()) { 1865 default: 1866 InitializerElementNotConstant(Init); 1867 return true; 1868 case Expr::ParenExprClass: 1869 return CheckAddressConstantExpression(cast<ParenExpr>(Init)->getSubExpr()); 1870 case Expr::StringLiteralClass: 1871 case Expr::ObjCStringLiteralClass: 1872 return false; 1873 case Expr::CallExprClass: 1874 case Expr::CXXOperatorCallExprClass: 1875 // __builtin___CFStringMakeConstantString is a valid constant l-value. 1876 if (cast<CallExpr>(Init)->isBuiltinCall() == 1877 Builtin::BI__builtin___CFStringMakeConstantString) 1878 return false; 1879 1880 InitializerElementNotConstant(Init); 1881 return true; 1882 1883 case Expr::UnaryOperatorClass: { 1884 const UnaryOperator *Exp = cast<UnaryOperator>(Init); 1885 1886 // C99 6.6p9 1887 if (Exp->getOpcode() == UnaryOperator::AddrOf) 1888 return CheckAddressConstantExpressionLValue(Exp->getSubExpr()); 1889 1890 if (Exp->getOpcode() == UnaryOperator::Extension) 1891 return CheckAddressConstantExpression(Exp->getSubExpr()); 1892 1893 InitializerElementNotConstant(Init); 1894 return true; 1895 } 1896 case Expr::BinaryOperatorClass: { 1897 // FIXME: Should we pedwarn for expressions like "a + 1 + 2"? 1898 const BinaryOperator *Exp = cast<BinaryOperator>(Init); 1899 1900 Expr *PExp = Exp->getLHS(); 1901 Expr *IExp = Exp->getRHS(); 1902 if (IExp->getType()->isPointerType()) 1903 std::swap(PExp, IExp); 1904 1905 // FIXME: Should we pedwarn if IExp isn't an integer constant expression? 1906 return CheckAddressConstantExpression(PExp) || 1907 CheckArithmeticConstantExpression(IExp); 1908 } 1909 case Expr::ImplicitCastExprClass: 1910 case Expr::CStyleCastExprClass: { 1911 const Expr* SubExpr = cast<CastExpr>(Init)->getSubExpr(); 1912 if (Init->getStmtClass() == Expr::ImplicitCastExprClass) { 1913 // Check for implicit promotion 1914 if (SubExpr->getType()->isFunctionType() || 1915 SubExpr->getType()->isArrayType()) 1916 return CheckAddressConstantExpressionLValue(SubExpr); 1917 } 1918 1919 // Check for pointer->pointer cast 1920 if (SubExpr->getType()->isPointerType()) 1921 return CheckAddressConstantExpression(SubExpr); 1922 1923 if (SubExpr->getType()->isIntegralType()) { 1924 // Check for the special-case of a pointer->int->pointer cast; 1925 // this isn't standard, but some code requires it. See 1926 // PR2720 for an example. 1927 if (const CastExpr* SubCast = dyn_cast<CastExpr>(SubExpr)) { 1928 if (SubCast->getSubExpr()->getType()->isPointerType()) { 1929 unsigned IntWidth = Context.getIntWidth(SubCast->getType()); 1930 unsigned PointerWidth = Context.getTypeSize(Context.VoidPtrTy); 1931 if (IntWidth >= PointerWidth) { 1932 return CheckAddressConstantExpression(SubCast->getSubExpr()); 1933 } 1934 } 1935 } 1936 } 1937 if (SubExpr->getType()->isArithmeticType()) { 1938 return CheckArithmeticConstantExpression(SubExpr); 1939 } 1940 1941 InitializerElementNotConstant(Init); 1942 return true; 1943 } 1944 case Expr::ConditionalOperatorClass: { 1945 // FIXME: Should we pedwarn here? 1946 const ConditionalOperator *Exp = cast<ConditionalOperator>(Init); 1947 if (!Exp->getCond()->getType()->isArithmeticType()) { 1948 InitializerElementNotConstant(Init); 1949 return true; 1950 } 1951 if (CheckArithmeticConstantExpression(Exp->getCond())) 1952 return true; 1953 if (Exp->getLHS() && 1954 CheckAddressConstantExpression(Exp->getLHS())) 1955 return true; 1956 return CheckAddressConstantExpression(Exp->getRHS()); 1957 } 1958 case Expr::AddrLabelExprClass: 1959 return false; 1960 } 1961} 1962 1963static const Expr* FindExpressionBaseAddress(const Expr* E); 1964 1965static const Expr* FindExpressionBaseAddressLValue(const Expr* E) { 1966 switch (E->getStmtClass()) { 1967 default: 1968 return E; 1969 case Expr::ParenExprClass: { 1970 const ParenExpr* PE = cast<ParenExpr>(E); 1971 return FindExpressionBaseAddressLValue(PE->getSubExpr()); 1972 } 1973 case Expr::MemberExprClass: { 1974 const MemberExpr *M = cast<MemberExpr>(E); 1975 if (M->isArrow()) 1976 return FindExpressionBaseAddress(M->getBase()); 1977 return FindExpressionBaseAddressLValue(M->getBase()); 1978 } 1979 case Expr::ArraySubscriptExprClass: { 1980 const ArraySubscriptExpr *ASE = cast<ArraySubscriptExpr>(E); 1981 return FindExpressionBaseAddress(ASE->getBase()); 1982 } 1983 case Expr::UnaryOperatorClass: { 1984 const UnaryOperator *Exp = cast<UnaryOperator>(E); 1985 1986 if (Exp->getOpcode() == UnaryOperator::Deref) 1987 return FindExpressionBaseAddress(Exp->getSubExpr()); 1988 1989 return E; 1990 } 1991 } 1992} 1993 1994static const Expr* FindExpressionBaseAddress(const Expr* E) { 1995 switch (E->getStmtClass()) { 1996 default: 1997 return E; 1998 case Expr::ParenExprClass: { 1999 const ParenExpr* PE = cast<ParenExpr>(E); 2000 return FindExpressionBaseAddress(PE->getSubExpr()); 2001 } 2002 case Expr::UnaryOperatorClass: { 2003 const UnaryOperator *Exp = cast<UnaryOperator>(E); 2004 2005 // C99 6.6p9 2006 if (Exp->getOpcode() == UnaryOperator::AddrOf) 2007 return FindExpressionBaseAddressLValue(Exp->getSubExpr()); 2008 2009 if (Exp->getOpcode() == UnaryOperator::Extension) 2010 return FindExpressionBaseAddress(Exp->getSubExpr()); 2011 2012 return E; 2013 } 2014 case Expr::BinaryOperatorClass: { 2015 const BinaryOperator *Exp = cast<BinaryOperator>(E); 2016 2017 Expr *PExp = Exp->getLHS(); 2018 Expr *IExp = Exp->getRHS(); 2019 if (IExp->getType()->isPointerType()) 2020 std::swap(PExp, IExp); 2021 2022 return FindExpressionBaseAddress(PExp); 2023 } 2024 case Expr::ImplicitCastExprClass: { 2025 const Expr* SubExpr = cast<ImplicitCastExpr>(E)->getSubExpr(); 2026 2027 // Check for implicit promotion 2028 if (SubExpr->getType()->isFunctionType() || 2029 SubExpr->getType()->isArrayType()) 2030 return FindExpressionBaseAddressLValue(SubExpr); 2031 2032 // Check for pointer->pointer cast 2033 if (SubExpr->getType()->isPointerType()) 2034 return FindExpressionBaseAddress(SubExpr); 2035 2036 // We assume that we have an arithmetic expression here; 2037 // if we don't, we'll figure it out later 2038 return 0; 2039 } 2040 case Expr::CStyleCastExprClass: { 2041 const Expr* SubExpr = cast<CastExpr>(E)->getSubExpr(); 2042 2043 // Check for pointer->pointer cast 2044 if (SubExpr->getType()->isPointerType()) 2045 return FindExpressionBaseAddress(SubExpr); 2046 2047 // We assume that we have an arithmetic expression here; 2048 // if we don't, we'll figure it out later 2049 return 0; 2050 } 2051 } 2052} 2053 2054bool Sema::CheckArithmeticConstantExpression(const Expr* Init) { 2055 switch (Init->getStmtClass()) { 2056 default: 2057 InitializerElementNotConstant(Init); 2058 return true; 2059 case Expr::ParenExprClass: { 2060 const ParenExpr* PE = cast<ParenExpr>(Init); 2061 return CheckArithmeticConstantExpression(PE->getSubExpr()); 2062 } 2063 case Expr::FloatingLiteralClass: 2064 case Expr::IntegerLiteralClass: 2065 case Expr::CharacterLiteralClass: 2066 case Expr::ImaginaryLiteralClass: 2067 case Expr::TypesCompatibleExprClass: 2068 case Expr::CXXBoolLiteralExprClass: 2069 return false; 2070 case Expr::CallExprClass: 2071 case Expr::CXXOperatorCallExprClass: { 2072 const CallExpr *CE = cast<CallExpr>(Init); 2073 2074 // Allow any constant foldable calls to builtins. 2075 if (CE->isBuiltinCall() && CE->isEvaluatable(Context)) 2076 return false; 2077 2078 InitializerElementNotConstant(Init); 2079 return true; 2080 } 2081 case Expr::DeclRefExprClass: 2082 case Expr::QualifiedDeclRefExprClass: { 2083 const Decl *D = cast<DeclRefExpr>(Init)->getDecl(); 2084 if (isa<EnumConstantDecl>(D)) 2085 return false; 2086 InitializerElementNotConstant(Init); 2087 return true; 2088 } 2089 case Expr::CompoundLiteralExprClass: 2090 // Allow "(vector type){2,4}"; normal C constraints don't allow this, 2091 // but vectors are allowed to be magic. 2092 if (Init->getType()->isVectorType()) 2093 return false; 2094 InitializerElementNotConstant(Init); 2095 return true; 2096 case Expr::UnaryOperatorClass: { 2097 const UnaryOperator *Exp = cast<UnaryOperator>(Init); 2098 2099 switch (Exp->getOpcode()) { 2100 // Address, indirect, pre/post inc/dec, etc are not valid constant exprs. 2101 // See C99 6.6p3. 2102 default: 2103 InitializerElementNotConstant(Init); 2104 return true; 2105 case UnaryOperator::OffsetOf: 2106 if (Exp->getSubExpr()->getType()->isConstantSizeType()) 2107 return false; 2108 InitializerElementNotConstant(Init); 2109 return true; 2110 case UnaryOperator::Extension: 2111 case UnaryOperator::LNot: 2112 case UnaryOperator::Plus: 2113 case UnaryOperator::Minus: 2114 case UnaryOperator::Not: 2115 return CheckArithmeticConstantExpression(Exp->getSubExpr()); 2116 } 2117 } 2118 case Expr::SizeOfAlignOfExprClass: { 2119 const SizeOfAlignOfExpr *Exp = cast<SizeOfAlignOfExpr>(Init); 2120 // Special check for void types, which are allowed as an extension 2121 if (Exp->getTypeOfArgument()->isVoidType()) 2122 return false; 2123 // alignof always evaluates to a constant. 2124 // FIXME: is sizeof(int[3.0]) a constant expression? 2125 if (Exp->isSizeOf() && !Exp->getTypeOfArgument()->isConstantSizeType()) { 2126 InitializerElementNotConstant(Init); 2127 return true; 2128 } 2129 return false; 2130 } 2131 case Expr::BinaryOperatorClass: { 2132 const BinaryOperator *Exp = cast<BinaryOperator>(Init); 2133 2134 if (Exp->getLHS()->getType()->isArithmeticType() && 2135 Exp->getRHS()->getType()->isArithmeticType()) { 2136 return CheckArithmeticConstantExpression(Exp->getLHS()) || 2137 CheckArithmeticConstantExpression(Exp->getRHS()); 2138 } 2139 2140 if (Exp->getLHS()->getType()->isPointerType() && 2141 Exp->getRHS()->getType()->isPointerType()) { 2142 const Expr* LHSBase = FindExpressionBaseAddress(Exp->getLHS()); 2143 const Expr* RHSBase = FindExpressionBaseAddress(Exp->getRHS()); 2144 2145 // Only allow a null (constant integer) base; we could 2146 // allow some additional cases if necessary, but this 2147 // is sufficient to cover offsetof-like constructs. 2148 if (!LHSBase && !RHSBase) { 2149 return CheckAddressConstantExpression(Exp->getLHS()) || 2150 CheckAddressConstantExpression(Exp->getRHS()); 2151 } 2152 } 2153 2154 InitializerElementNotConstant(Init); 2155 return true; 2156 } 2157 case Expr::ImplicitCastExprClass: 2158 case Expr::CStyleCastExprClass: { 2159 const Expr *SubExpr = cast<CastExpr>(Init)->getSubExpr(); 2160 if (SubExpr->getType()->isArithmeticType()) 2161 return CheckArithmeticConstantExpression(SubExpr); 2162 2163 if (SubExpr->getType()->isPointerType()) { 2164 const Expr* Base = FindExpressionBaseAddress(SubExpr); 2165 // If the pointer has a null base, this is an offsetof-like construct 2166 if (!Base) 2167 return CheckAddressConstantExpression(SubExpr); 2168 } 2169 2170 InitializerElementNotConstant(Init); 2171 return true; 2172 } 2173 case Expr::ConditionalOperatorClass: { 2174 const ConditionalOperator *Exp = cast<ConditionalOperator>(Init); 2175 2176 // If GNU extensions are disabled, we require all operands to be arithmetic 2177 // constant expressions. 2178 if (getLangOptions().NoExtensions) { 2179 return CheckArithmeticConstantExpression(Exp->getCond()) || 2180 (Exp->getLHS() && CheckArithmeticConstantExpression(Exp->getLHS())) || 2181 CheckArithmeticConstantExpression(Exp->getRHS()); 2182 } 2183 2184 // Otherwise, we have to emulate some of the behavior of fold here. 2185 // Basically GCC treats things like "4 ? 1 : somefunc()" as a constant 2186 // because it can constant fold things away. To retain compatibility with 2187 // GCC code, we see if we can fold the condition to a constant (which we 2188 // should always be able to do in theory). If so, we only require the 2189 // specified arm of the conditional to be a constant. This is a horrible 2190 // hack, but is require by real world code that uses __builtin_constant_p. 2191 Expr::EvalResult EvalResult; 2192 if (!Exp->getCond()->Evaluate(EvalResult, Context) || 2193 EvalResult.HasSideEffects) { 2194 // If Evaluate couldn't fold it, CheckArithmeticConstantExpression 2195 // won't be able to either. Use it to emit the diagnostic though. 2196 bool Res = CheckArithmeticConstantExpression(Exp->getCond()); 2197 assert(Res && "Evaluate couldn't evaluate this constant?"); 2198 return Res; 2199 } 2200 2201 // Verify that the side following the condition is also a constant. 2202 const Expr *TrueSide = Exp->getLHS(), *FalseSide = Exp->getRHS(); 2203 if (EvalResult.Val.getInt() == 0) 2204 std::swap(TrueSide, FalseSide); 2205 2206 if (TrueSide && CheckArithmeticConstantExpression(TrueSide)) 2207 return true; 2208 2209 // Okay, the evaluated side evaluates to a constant, so we accept this. 2210 // Check to see if the other side is obviously not a constant. If so, 2211 // emit a warning that this is a GNU extension. 2212 if (FalseSide && !FalseSide->isEvaluatable(Context)) 2213 Diag(Init->getExprLoc(), 2214 diag::ext_typecheck_expression_not_constant_but_accepted) 2215 << FalseSide->getSourceRange(); 2216 return false; 2217 } 2218 } 2219} 2220 2221bool Sema::CheckForConstantInitializer(Expr *Init, QualType DclT) { 2222 Expr::EvalResult Result; 2223 2224 Init = Init->IgnoreParens(); 2225 2226 if (Init->Evaluate(Result, Context) && !Result.HasSideEffects) 2227 return false; 2228 2229 // Look through CXXDefaultArgExprs; they have no meaning in this context. 2230 if (CXXDefaultArgExpr* DAE = dyn_cast<CXXDefaultArgExpr>(Init)) 2231 return CheckForConstantInitializer(DAE->getExpr(), DclT); 2232 2233 if (CompoundLiteralExpr *e = dyn_cast<CompoundLiteralExpr>(Init)) 2234 return CheckForConstantInitializer(e->getInitializer(), DclT); 2235 2236 if (InitListExpr *Exp = dyn_cast<InitListExpr>(Init)) { 2237 unsigned numInits = Exp->getNumInits(); 2238 for (unsigned i = 0; i < numInits; i++) { 2239 // FIXME: Need to get the type of the declaration for C++, 2240 // because it could be a reference? 2241 if (CheckForConstantInitializer(Exp->getInit(i), 2242 Exp->getInit(i)->getType())) 2243 return true; 2244 } 2245 return false; 2246 } 2247 2248 // FIXME: We can probably remove some of this code below, now that 2249 // Expr::Evaluate is doing the heavy lifting for scalars. 2250 2251 if (Init->isNullPointerConstant(Context)) 2252 return false; 2253 if (Init->getType()->isArithmeticType()) { 2254 QualType InitTy = Context.getCanonicalType(Init->getType()) 2255 .getUnqualifiedType(); 2256 if (InitTy == Context.BoolTy) { 2257 // Special handling for pointers implicitly cast to bool; 2258 // (e.g. "_Bool rr = &rr;"). This is only legal at the top level. 2259 if (ImplicitCastExpr* ICE = dyn_cast<ImplicitCastExpr>(Init)) { 2260 Expr* SubE = ICE->getSubExpr(); 2261 if (SubE->getType()->isPointerType() || 2262 SubE->getType()->isArrayType() || 2263 SubE->getType()->isFunctionType()) { 2264 return CheckAddressConstantExpression(Init); 2265 } 2266 } 2267 } else if (InitTy->isIntegralType()) { 2268 Expr* SubE = 0; 2269 if (CastExpr* CE = dyn_cast<CastExpr>(Init)) 2270 SubE = CE->getSubExpr(); 2271 // Special check for pointer cast to int; we allow as an extension 2272 // an address constant cast to an integer if the integer 2273 // is of an appropriate width (this sort of code is apparently used 2274 // in some places). 2275 // FIXME: Add pedwarn? 2276 // FIXME: Don't allow bitfields here! Need the FieldDecl for that. 2277 if (SubE && (SubE->getType()->isPointerType() || 2278 SubE->getType()->isArrayType() || 2279 SubE->getType()->isFunctionType())) { 2280 unsigned IntWidth = Context.getTypeSize(Init->getType()); 2281 unsigned PointerWidth = Context.getTypeSize(Context.VoidPtrTy); 2282 if (IntWidth >= PointerWidth) 2283 return CheckAddressConstantExpression(Init); 2284 } 2285 } 2286 2287 return CheckArithmeticConstantExpression(Init); 2288 } 2289 2290 if (Init->getType()->isPointerType()) 2291 return CheckAddressConstantExpression(Init); 2292 2293 // An array type at the top level that isn't an init-list must 2294 // be a string literal 2295 if (Init->getType()->isArrayType()) 2296 return false; 2297 2298 if (Init->getType()->isFunctionType()) 2299 return false; 2300 2301 // Allow block exprs at top level. 2302 if (Init->getType()->isBlockPointerType()) 2303 return false; 2304 2305 InitializerElementNotConstant(Init); 2306 return true; 2307} 2308 2309void Sema::AddInitializerToDecl(DeclTy *dcl, ExprArg init) { 2310 Decl *RealDecl = static_cast<Decl *>(dcl); 2311 Expr *Init = static_cast<Expr *>(init.release()); 2312 assert(Init && "missing initializer"); 2313 2314 // If there is no declaration, there was an error parsing it. Just ignore 2315 // the initializer. 2316 if (RealDecl == 0) { 2317 delete Init; 2318 return; 2319 } 2320 2321 VarDecl *VDecl = dyn_cast<VarDecl>(RealDecl); 2322 if (!VDecl) { 2323 Diag(dyn_cast<ScopedDecl>(RealDecl)->getLocation(), 2324 diag::err_illegal_initializer); 2325 RealDecl->setInvalidDecl(); 2326 return; 2327 } 2328 // Get the decls type and save a reference for later, since 2329 // CheckInitializerTypes may change it. 2330 QualType DclT = VDecl->getType(), SavT = DclT; 2331 if (VDecl->isBlockVarDecl()) { 2332 VarDecl::StorageClass SC = VDecl->getStorageClass(); 2333 if (SC == VarDecl::Extern) { // C99 6.7.8p5 2334 Diag(VDecl->getLocation(), diag::err_block_extern_cant_init); 2335 VDecl->setInvalidDecl(); 2336 } else if (!VDecl->isInvalidDecl()) { 2337 if (CheckInitializerTypes(Init, DclT, VDecl->getLocation(), 2338 VDecl->getDeclName())) 2339 VDecl->setInvalidDecl(); 2340 2341 // C++ 3.6.2p2, allow dynamic initialization of static initializers. 2342 if (!getLangOptions().CPlusPlus) { 2343 if (SC == VarDecl::Static) // C99 6.7.8p4. 2344 CheckForConstantInitializer(Init, DclT); 2345 } 2346 } 2347 } else if (VDecl->isFileVarDecl()) { 2348 if (VDecl->getStorageClass() == VarDecl::Extern) 2349 Diag(VDecl->getLocation(), diag::warn_extern_init); 2350 if (!VDecl->isInvalidDecl()) 2351 if (CheckInitializerTypes(Init, DclT, VDecl->getLocation(), 2352 VDecl->getDeclName())) 2353 VDecl->setInvalidDecl(); 2354 2355 // C++ 3.6.2p2, allow dynamic initialization of static initializers. 2356 if (!getLangOptions().CPlusPlus) { 2357 // C99 6.7.8p4. All file scoped initializers need to be constant. 2358 CheckForConstantInitializer(Init, DclT); 2359 } 2360 } 2361 // If the type changed, it means we had an incomplete type that was 2362 // completed by the initializer. For example: 2363 // int ary[] = { 1, 3, 5 }; 2364 // "ary" transitions from a VariableArrayType to a ConstantArrayType. 2365 if (!VDecl->isInvalidDecl() && (DclT != SavT)) { 2366 VDecl->setType(DclT); 2367 Init->setType(DclT); 2368 } 2369 2370 // Attach the initializer to the decl. 2371 VDecl->setInit(Init); 2372 return; 2373} 2374 2375void Sema::ActOnUninitializedDecl(DeclTy *dcl) { 2376 Decl *RealDecl = static_cast<Decl *>(dcl); 2377 2378 // If there is no declaration, there was an error parsing it. Just ignore it. 2379 if (RealDecl == 0) 2380 return; 2381 2382 if (VarDecl *Var = dyn_cast<VarDecl>(RealDecl)) { 2383 QualType Type = Var->getType(); 2384 // C++ [dcl.init.ref]p3: 2385 // The initializer can be omitted for a reference only in a 2386 // parameter declaration (8.3.5), in the declaration of a 2387 // function return type, in the declaration of a class member 2388 // within its class declaration (9.2), and where the extern 2389 // specifier is explicitly used. 2390 if (Type->isReferenceType() && 2391 Var->getStorageClass() != VarDecl::Extern && 2392 Var->getStorageClass() != VarDecl::PrivateExtern) { 2393 Diag(Var->getLocation(), diag::err_reference_var_requires_init) 2394 << Var->getDeclName() 2395 << SourceRange(Var->getLocation(), Var->getLocation()); 2396 Var->setInvalidDecl(); 2397 return; 2398 } 2399 2400 // C++ [dcl.init]p9: 2401 // 2402 // If no initializer is specified for an object, and the object 2403 // is of (possibly cv-qualified) non-POD class type (or array 2404 // thereof), the object shall be default-initialized; if the 2405 // object is of const-qualified type, the underlying class type 2406 // shall have a user-declared default constructor. 2407 if (getLangOptions().CPlusPlus) { 2408 QualType InitType = Type; 2409 if (const ArrayType *Array = Context.getAsArrayType(Type)) 2410 InitType = Array->getElementType(); 2411 if (Var->getStorageClass() != VarDecl::Extern && 2412 Var->getStorageClass() != VarDecl::PrivateExtern && 2413 InitType->isRecordType()) { 2414 const CXXConstructorDecl *Constructor 2415 = PerformInitializationByConstructor(InitType, 0, 0, 2416 Var->getLocation(), 2417 SourceRange(Var->getLocation(), 2418 Var->getLocation()), 2419 Var->getDeclName(), 2420 IK_Default); 2421 if (!Constructor) 2422 Var->setInvalidDecl(); 2423 } 2424 } 2425 2426#if 0 2427 // FIXME: Temporarily disabled because we are not properly parsing 2428 // linkage specifications on declarations, e.g., 2429 // 2430 // extern "C" const CGPoint CGPointerZero; 2431 // 2432 // C++ [dcl.init]p9: 2433 // 2434 // If no initializer is specified for an object, and the 2435 // object is of (possibly cv-qualified) non-POD class type (or 2436 // array thereof), the object shall be default-initialized; if 2437 // the object is of const-qualified type, the underlying class 2438 // type shall have a user-declared default 2439 // constructor. Otherwise, if no initializer is specified for 2440 // an object, the object and its subobjects, if any, have an 2441 // indeterminate initial value; if the object or any of its 2442 // subobjects are of const-qualified type, the program is 2443 // ill-formed. 2444 // 2445 // This isn't technically an error in C, so we don't diagnose it. 2446 // 2447 // FIXME: Actually perform the POD/user-defined default 2448 // constructor check. 2449 if (getLangOptions().CPlusPlus && 2450 Context.getCanonicalType(Type).isConstQualified() && 2451 Var->getStorageClass() != VarDecl::Extern) 2452 Diag(Var->getLocation(), diag::err_const_var_requires_init) 2453 << Var->getName() 2454 << SourceRange(Var->getLocation(), Var->getLocation()); 2455#endif 2456 } 2457} 2458 2459/// The declarators are chained together backwards, reverse the list. 2460Sema::DeclTy *Sema::FinalizeDeclaratorGroup(Scope *S, DeclTy *group) { 2461 // Often we have single declarators, handle them quickly. 2462 Decl *GroupDecl = static_cast<Decl*>(group); 2463 if (GroupDecl == 0) 2464 return 0; 2465 2466 ScopedDecl *Group = dyn_cast<ScopedDecl>(GroupDecl); 2467 ScopedDecl *NewGroup = 0; 2468 if (Group->getNextDeclarator() == 0) 2469 NewGroup = Group; 2470 else { // reverse the list. 2471 while (Group) { 2472 ScopedDecl *Next = Group->getNextDeclarator(); 2473 Group->setNextDeclarator(NewGroup); 2474 NewGroup = Group; 2475 Group = Next; 2476 } 2477 } 2478 // Perform semantic analysis that depends on having fully processed both 2479 // the declarator and initializer. 2480 for (ScopedDecl *ID = NewGroup; ID; ID = ID->getNextDeclarator()) { 2481 VarDecl *IDecl = dyn_cast<VarDecl>(ID); 2482 if (!IDecl) 2483 continue; 2484 QualType T = IDecl->getType(); 2485 2486 if (T->isVariableArrayType()) { 2487 const VariableArrayType *VAT = Context.getAsVariableArrayType(T); 2488 2489 // FIXME: This won't give the correct result for 2490 // int a[10][n]; 2491 SourceRange SizeRange = VAT->getSizeExpr()->getSourceRange(); 2492 if (IDecl->isFileVarDecl()) { 2493 Diag(IDecl->getLocation(), diag::err_vla_decl_in_file_scope) << 2494 SizeRange; 2495 2496 IDecl->setInvalidDecl(); 2497 } else { 2498 // C99 6.7.5.2p2: If an identifier is declared to be an object with 2499 // static storage duration, it shall not have a variable length array. 2500 if (IDecl->getStorageClass() == VarDecl::Static) { 2501 Diag(IDecl->getLocation(), diag::err_vla_decl_has_static_storage) 2502 << SizeRange; 2503 IDecl->setInvalidDecl(); 2504 } else if (IDecl->getStorageClass() == VarDecl::Extern) { 2505 Diag(IDecl->getLocation(), diag::err_vla_decl_has_extern_linkage) 2506 << SizeRange; 2507 IDecl->setInvalidDecl(); 2508 } 2509 } 2510 } else if (T->isVariablyModifiedType()) { 2511 if (IDecl->isFileVarDecl()) { 2512 Diag(IDecl->getLocation(), diag::err_vm_decl_in_file_scope); 2513 IDecl->setInvalidDecl(); 2514 } else { 2515 if (IDecl->getStorageClass() == VarDecl::Extern) { 2516 Diag(IDecl->getLocation(), diag::err_vm_decl_has_extern_linkage); 2517 IDecl->setInvalidDecl(); 2518 } 2519 } 2520 } 2521 2522 // Block scope. C99 6.7p7: If an identifier for an object is declared with 2523 // no linkage (C99 6.2.2p6), the type for the object shall be complete... 2524 if (IDecl->isBlockVarDecl() && 2525 IDecl->getStorageClass() != VarDecl::Extern) { 2526 if (T->isIncompleteType() && !IDecl->isInvalidDecl()) { 2527 Diag(IDecl->getLocation(), diag::err_typecheck_decl_incomplete_type)<<T; 2528 IDecl->setInvalidDecl(); 2529 } 2530 } 2531 // File scope. C99 6.9.2p2: A declaration of an identifier for and 2532 // object that has file scope without an initializer, and without a 2533 // storage-class specifier or with the storage-class specifier "static", 2534 // constitutes a tentative definition. Note: A tentative definition with 2535 // external linkage is valid (C99 6.2.2p5). 2536 if (isTentativeDefinition(IDecl)) { 2537 if (T->isIncompleteArrayType()) { 2538 // C99 6.9.2 (p2, p5): Implicit initialization causes an incomplete 2539 // array to be completed. Don't issue a diagnostic. 2540 } else if (T->isIncompleteType() && !IDecl->isInvalidDecl()) { 2541 // C99 6.9.2p3: If the declaration of an identifier for an object is 2542 // a tentative definition and has internal linkage (C99 6.2.2p3), the 2543 // declared type shall not be an incomplete type. 2544 Diag(IDecl->getLocation(), diag::err_typecheck_decl_incomplete_type)<<T; 2545 IDecl->setInvalidDecl(); 2546 } 2547 } 2548 if (IDecl->isFileVarDecl()) 2549 CheckForFileScopedRedefinitions(S, IDecl); 2550 } 2551 return NewGroup; 2552} 2553 2554/// ActOnParamDeclarator - Called from Parser::ParseFunctionDeclarator() 2555/// to introduce parameters into function prototype scope. 2556Sema::DeclTy * 2557Sema::ActOnParamDeclarator(Scope *S, Declarator &D) { 2558 const DeclSpec &DS = D.getDeclSpec(); 2559 2560 // Verify C99 6.7.5.3p2: The only SCS allowed is 'register'. 2561 VarDecl::StorageClass StorageClass = VarDecl::None; 2562 if (DS.getStorageClassSpec() == DeclSpec::SCS_register) { 2563 StorageClass = VarDecl::Register; 2564 } else if (DS.getStorageClassSpec() != DeclSpec::SCS_unspecified) { 2565 Diag(DS.getStorageClassSpecLoc(), 2566 diag::err_invalid_storage_class_in_func_decl); 2567 D.getMutableDeclSpec().ClearStorageClassSpecs(); 2568 } 2569 if (DS.isThreadSpecified()) { 2570 Diag(DS.getThreadSpecLoc(), 2571 diag::err_invalid_storage_class_in_func_decl); 2572 D.getMutableDeclSpec().ClearStorageClassSpecs(); 2573 } 2574 2575 // Check that there are no default arguments inside the type of this 2576 // parameter (C++ only). 2577 if (getLangOptions().CPlusPlus) 2578 CheckExtraCXXDefaultArguments(D); 2579 2580 // In this context, we *do not* check D.getInvalidType(). If the declarator 2581 // type was invalid, GetTypeForDeclarator() still returns a "valid" type, 2582 // though it will not reflect the user specified type. 2583 QualType parmDeclType = GetTypeForDeclarator(D, S); 2584 2585 assert(!parmDeclType.isNull() && "GetTypeForDeclarator() returned null type"); 2586 2587 // TODO: CHECK FOR CONFLICTS, multiple decls with same name in one scope. 2588 // Can this happen for params? We already checked that they don't conflict 2589 // among each other. Here they can only shadow globals, which is ok. 2590 IdentifierInfo *II = D.getIdentifier(); 2591 if (Decl *PrevDecl = LookupDecl(II, Decl::IDNS_Ordinary, S)) { 2592 if (PrevDecl->isTemplateParameter()) { 2593 // Maybe we will complain about the shadowed template parameter. 2594 DiagnoseTemplateParameterShadow(D.getIdentifierLoc(), PrevDecl); 2595 // Just pretend that we didn't see the previous declaration. 2596 PrevDecl = 0; 2597 } else if (S->isDeclScope(PrevDecl)) { 2598 Diag(D.getIdentifierLoc(), diag::err_param_redefinition) << II; 2599 2600 // Recover by removing the name 2601 II = 0; 2602 D.SetIdentifier(0, D.getIdentifierLoc()); 2603 } 2604 } 2605 2606 // Perform the default function/array conversion (C99 6.7.5.3p[7,8]). 2607 // Doing the promotion here has a win and a loss. The win is the type for 2608 // both Decl's and DeclRefExpr's will match (a convenient invariant for the 2609 // code generator). The loss is the orginal type isn't preserved. For example: 2610 // 2611 // void func(int parmvardecl[5]) { // convert "int [5]" to "int *" 2612 // int blockvardecl[5]; 2613 // sizeof(parmvardecl); // size == 4 2614 // sizeof(blockvardecl); // size == 20 2615 // } 2616 // 2617 // For expressions, all implicit conversions are captured using the 2618 // ImplicitCastExpr AST node (we have no such mechanism for Decl's). 2619 // 2620 // FIXME: If a source translation tool needs to see the original type, then 2621 // we need to consider storing both types (in ParmVarDecl)... 2622 // 2623 if (parmDeclType->isArrayType()) { 2624 // int x[restrict 4] -> int *restrict 2625 parmDeclType = Context.getArrayDecayedType(parmDeclType); 2626 } else if (parmDeclType->isFunctionType()) 2627 parmDeclType = Context.getPointerType(parmDeclType); 2628 2629 ParmVarDecl *New = ParmVarDecl::Create(Context, CurContext, 2630 D.getIdentifierLoc(), II, 2631 parmDeclType, StorageClass, 2632 0, 0); 2633 2634 if (D.getInvalidType()) 2635 New->setInvalidDecl(); 2636 2637 // Parameter declarators cannot be qualified (C++ [dcl.meaning]p1). 2638 if (D.getCXXScopeSpec().isSet()) { 2639 Diag(D.getIdentifierLoc(), diag::err_qualified_param_declarator) 2640 << D.getCXXScopeSpec().getRange(); 2641 New->setInvalidDecl(); 2642 } 2643 2644 // Add the parameter declaration into this scope. 2645 S->AddDecl(New); 2646 if (II) 2647 IdResolver.AddDecl(New); 2648 2649 ProcessDeclAttributes(New, D); 2650 return New; 2651 2652} 2653 2654Sema::DeclTy *Sema::ActOnStartOfFunctionDef(Scope *FnBodyScope, Declarator &D) { 2655 assert(getCurFunctionDecl() == 0 && "Function parsing confused"); 2656 assert(D.getTypeObject(0).Kind == DeclaratorChunk::Function && 2657 "Not a function declarator!"); 2658 DeclaratorChunk::FunctionTypeInfo &FTI = D.getTypeObject(0).Fun; 2659 2660 // Verify 6.9.1p6: 'every identifier in the identifier list shall be declared' 2661 // for a K&R function. 2662 if (!FTI.hasPrototype) { 2663 for (unsigned i = 0, e = FTI.NumArgs; i != e; ++i) { 2664 if (FTI.ArgInfo[i].Param == 0) { 2665 Diag(FTI.ArgInfo[i].IdentLoc, diag::ext_param_not_declared) 2666 << FTI.ArgInfo[i].Ident; 2667 // Implicitly declare the argument as type 'int' for lack of a better 2668 // type. 2669 DeclSpec DS; 2670 const char* PrevSpec; // unused 2671 DS.SetTypeSpecType(DeclSpec::TST_int, FTI.ArgInfo[i].IdentLoc, 2672 PrevSpec); 2673 Declarator ParamD(DS, Declarator::KNRTypeListContext); 2674 ParamD.SetIdentifier(FTI.ArgInfo[i].Ident, FTI.ArgInfo[i].IdentLoc); 2675 FTI.ArgInfo[i].Param = ActOnParamDeclarator(FnBodyScope, ParamD); 2676 } 2677 } 2678 } else { 2679 // FIXME: Diagnose arguments without names in C. 2680 } 2681 2682 Scope *ParentScope = FnBodyScope->getParent(); 2683 2684 return ActOnStartOfFunctionDef(FnBodyScope, 2685 ActOnDeclarator(ParentScope, D, 0, 2686 /*IsFunctionDefinition=*/true)); 2687} 2688 2689Sema::DeclTy *Sema::ActOnStartOfFunctionDef(Scope *FnBodyScope, DeclTy *D) { 2690 Decl *decl = static_cast<Decl*>(D); 2691 FunctionDecl *FD = cast<FunctionDecl>(decl); 2692 2693 // See if this is a redefinition. 2694 const FunctionDecl *Definition; 2695 if (FD->getBody(Definition)) { 2696 Diag(FD->getLocation(), diag::err_redefinition) << FD->getDeclName(); 2697 Diag(Definition->getLocation(), diag::note_previous_definition); 2698 } 2699 2700 PushDeclContext(FnBodyScope, FD); 2701 2702 // Check the validity of our function parameters 2703 CheckParmsForFunctionDef(FD); 2704 2705 // Introduce our parameters into the function scope 2706 for (unsigned p = 0, NumParams = FD->getNumParams(); p < NumParams; ++p) { 2707 ParmVarDecl *Param = FD->getParamDecl(p); 2708 // If this has an identifier, add it to the scope stack. 2709 if (Param->getIdentifier()) 2710 PushOnScopeChains(Param, FnBodyScope); 2711 } 2712 2713 // Checking attributes of current function definition 2714 // dllimport attribute. 2715 if (FD->getAttr<DLLImportAttr>() && (!FD->getAttr<DLLExportAttr>())) { 2716 // dllimport attribute cannot be applied to definition. 2717 if (!(FD->getAttr<DLLImportAttr>())->isInherited()) { 2718 Diag(FD->getLocation(), 2719 diag::err_attribute_can_be_applied_only_to_symbol_declaration) 2720 << "dllimport"; 2721 FD->setInvalidDecl(); 2722 return FD; 2723 } else { 2724 // If a symbol previously declared dllimport is later defined, the 2725 // attribute is ignored in subsequent references, and a warning is 2726 // emitted. 2727 Diag(FD->getLocation(), 2728 diag::warn_redeclaration_without_attribute_prev_attribute_ignored) 2729 << FD->getNameAsCString() << "dllimport"; 2730 } 2731 } 2732 return FD; 2733} 2734 2735Sema::DeclTy *Sema::ActOnFinishFunctionBody(DeclTy *D, StmtArg BodyArg) { 2736 Decl *dcl = static_cast<Decl *>(D); 2737 Stmt *Body = static_cast<Stmt*>(BodyArg.release()); 2738 if (FunctionDecl *FD = dyn_cast_or_null<FunctionDecl>(dcl)) { 2739 FD->setBody(Body); 2740 assert(FD == getCurFunctionDecl() && "Function parsing confused"); 2741 } else if (ObjCMethodDecl *MD = dyn_cast_or_null<ObjCMethodDecl>(dcl)) { 2742 MD->setBody((Stmt*)Body); 2743 } else 2744 return 0; 2745 PopDeclContext(); 2746 // Verify and clean out per-function state. 2747 2748 // Check goto/label use. 2749 for (llvm::DenseMap<IdentifierInfo*, LabelStmt*>::iterator 2750 I = LabelMap.begin(), E = LabelMap.end(); I != E; ++I) { 2751 // Verify that we have no forward references left. If so, there was a goto 2752 // or address of a label taken, but no definition of it. Label fwd 2753 // definitions are indicated with a null substmt. 2754 if (I->second->getSubStmt() == 0) { 2755 LabelStmt *L = I->second; 2756 // Emit error. 2757 Diag(L->getIdentLoc(), diag::err_undeclared_label_use) << L->getName(); 2758 2759 // At this point, we have gotos that use the bogus label. Stitch it into 2760 // the function body so that they aren't leaked and that the AST is well 2761 // formed. 2762 if (Body) { 2763 L->setSubStmt(new NullStmt(L->getIdentLoc())); 2764 cast<CompoundStmt>(Body)->push_back(L); 2765 } else { 2766 // The whole function wasn't parsed correctly, just delete this. 2767 delete L; 2768 } 2769 } 2770 } 2771 LabelMap.clear(); 2772 2773 return D; 2774} 2775 2776/// ImplicitlyDefineFunction - An undeclared identifier was used in a function 2777/// call, forming a call to an implicitly defined function (per C99 6.5.1p2). 2778ScopedDecl *Sema::ImplicitlyDefineFunction(SourceLocation Loc, 2779 IdentifierInfo &II, Scope *S) { 2780 // Extension in C99. Legal in C90, but warn about it. 2781 if (getLangOptions().C99) 2782 Diag(Loc, diag::ext_implicit_function_decl) << &II; 2783 else 2784 Diag(Loc, diag::warn_implicit_function_decl) << &II; 2785 2786 // FIXME: handle stuff like: 2787 // void foo() { extern float X(); } 2788 // void bar() { X(); } <-- implicit decl for X in another scope. 2789 2790 // Set a Declarator for the implicit definition: int foo(); 2791 const char *Dummy; 2792 DeclSpec DS; 2793 bool Error = DS.SetTypeSpecType(DeclSpec::TST_int, Loc, Dummy); 2794 Error = Error; // Silence warning. 2795 assert(!Error && "Error setting up implicit decl!"); 2796 Declarator D(DS, Declarator::BlockContext); 2797 D.AddTypeInfo(DeclaratorChunk::getFunction(false, false, 0, 0, 0, Loc)); 2798 D.SetIdentifier(&II, Loc); 2799 2800 // Insert this function into translation-unit scope. 2801 2802 DeclContext *PrevDC = CurContext; 2803 CurContext = Context.getTranslationUnitDecl(); 2804 2805 FunctionDecl *FD = 2806 dyn_cast<FunctionDecl>(static_cast<Decl*>(ActOnDeclarator(TUScope, D, 0))); 2807 FD->setImplicit(); 2808 2809 CurContext = PrevDC; 2810 2811 return FD; 2812} 2813 2814 2815TypedefDecl *Sema::ParseTypedefDecl(Scope *S, Declarator &D, QualType T, 2816 ScopedDecl *LastDeclarator) { 2817 assert(D.getIdentifier() && "Wrong callback for declspec without declarator"); 2818 assert(!T.isNull() && "GetTypeForDeclarator() returned null type"); 2819 2820 // Scope manipulation handled by caller. 2821 TypedefDecl *NewTD = TypedefDecl::Create(Context, CurContext, 2822 D.getIdentifierLoc(), 2823 D.getIdentifier(), 2824 T, LastDeclarator); 2825 if (D.getInvalidType()) 2826 NewTD->setInvalidDecl(); 2827 return NewTD; 2828} 2829 2830/// ActOnTag - This is invoked when we see 'struct foo' or 'struct {'. In the 2831/// former case, Name will be non-null. In the later case, Name will be null. 2832/// TagType indicates what kind of tag this is. TK indicates whether this is a 2833/// reference/declaration/definition of a tag. 2834Sema::DeclTy *Sema::ActOnTag(Scope *S, unsigned TagType, TagKind TK, 2835 SourceLocation KWLoc, const CXXScopeSpec &SS, 2836 IdentifierInfo *Name, SourceLocation NameLoc, 2837 AttributeList *Attr, 2838 MultiTemplateParamsArg TemplateParameterLists) { 2839 // If this is not a definition, it must have a name. 2840 assert((Name != 0 || TK == TK_Definition) && 2841 "Nameless record must be a definition!"); 2842 2843 TagDecl::TagKind Kind; 2844 switch (TagType) { 2845 default: assert(0 && "Unknown tag type!"); 2846 case DeclSpec::TST_struct: Kind = TagDecl::TK_struct; break; 2847 case DeclSpec::TST_union: Kind = TagDecl::TK_union; break; 2848 case DeclSpec::TST_class: Kind = TagDecl::TK_class; break; 2849 case DeclSpec::TST_enum: Kind = TagDecl::TK_enum; break; 2850 } 2851 2852 DeclContext *DC = CurContext; 2853 ScopedDecl *PrevDecl = 0; 2854 2855 if (Name && SS.isNotEmpty()) { 2856 // We have a nested-name tag ('struct foo::bar'). 2857 2858 // Check for invalid 'foo::'. 2859 if (SS.isInvalid()) { 2860 Name = 0; 2861 goto CreateNewDecl; 2862 } 2863 2864 DC = static_cast<DeclContext*>(SS.getScopeRep()); 2865 // Look-up name inside 'foo::'. 2866 PrevDecl = dyn_cast_or_null<TagDecl>(LookupDecl(Name, Decl::IDNS_Tag,S,DC)); 2867 2868 // A tag 'foo::bar' must already exist. 2869 if (PrevDecl == 0) { 2870 Diag(NameLoc, diag::err_not_tag_in_scope) << Name << SS.getRange(); 2871 Name = 0; 2872 goto CreateNewDecl; 2873 } 2874 } else { 2875 // If this is a named struct, check to see if there was a previous forward 2876 // declaration or definition. 2877 // Use ScopedDecl instead of TagDecl, because a NamespaceDecl may come up. 2878 PrevDecl = dyn_cast_or_null<ScopedDecl>(LookupDecl(Name, Decl::IDNS_Tag,S)); 2879 2880 if (!getLangOptions().CPlusPlus && TK != TK_Reference) { 2881 // FIXME: This makes sure that we ignore the contexts associated 2882 // with C structs, unions, and enums when looking for a matching 2883 // tag declaration or definition. See the similar lookup tweak 2884 // in Sema::LookupDecl; is there a better way to deal with this? 2885 while (isa<RecordDecl>(DC) || isa<EnumDecl>(DC)) 2886 DC = DC->getParent(); 2887 } 2888 } 2889 2890 if (PrevDecl && PrevDecl->isTemplateParameter()) { 2891 // Maybe we will complain about the shadowed template parameter. 2892 DiagnoseTemplateParameterShadow(NameLoc, PrevDecl); 2893 // Just pretend that we didn't see the previous declaration. 2894 PrevDecl = 0; 2895 } 2896 2897 if (PrevDecl) { 2898 assert((isa<TagDecl>(PrevDecl) || isa<NamespaceDecl>(PrevDecl)) && 2899 "unexpected Decl type"); 2900 if (TagDecl *PrevTagDecl = dyn_cast<TagDecl>(PrevDecl)) { 2901 // If this is a use of a previous tag, or if the tag is already declared 2902 // in the same scope (so that the definition/declaration completes or 2903 // rementions the tag), reuse the decl. 2904 if (TK == TK_Reference || isDeclInScope(PrevDecl, DC, S)) { 2905 // Make sure that this wasn't declared as an enum and now used as a 2906 // struct or something similar. 2907 if (PrevTagDecl->getTagKind() != Kind) { 2908 Diag(KWLoc, diag::err_use_with_wrong_tag) << Name; 2909 Diag(PrevDecl->getLocation(), diag::note_previous_use); 2910 // Recover by making this an anonymous redefinition. 2911 Name = 0; 2912 PrevDecl = 0; 2913 } else { 2914 // If this is a use, just return the declaration we found. 2915 2916 // FIXME: In the future, return a variant or some other clue 2917 // for the consumer of this Decl to know it doesn't own it. 2918 // For our current ASTs this shouldn't be a problem, but will 2919 // need to be changed with DeclGroups. 2920 if (TK == TK_Reference) 2921 return PrevDecl; 2922 2923 // Diagnose attempts to redefine a tag. 2924 if (TK == TK_Definition) { 2925 if (TagDecl *Def = PrevTagDecl->getDefinition(Context)) { 2926 Diag(NameLoc, diag::err_redefinition) << Name; 2927 Diag(Def->getLocation(), diag::note_previous_definition); 2928 // If this is a redefinition, recover by making this struct be 2929 // anonymous, which will make any later references get the previous 2930 // definition. 2931 Name = 0; 2932 PrevDecl = 0; 2933 } 2934 // Okay, this is definition of a previously declared or referenced 2935 // tag PrevDecl. We're going to create a new Decl for it. 2936 } 2937 } 2938 // If we get here we have (another) forward declaration or we 2939 // have a definition. Just create a new decl. 2940 } else { 2941 // If we get here, this is a definition of a new tag type in a nested 2942 // scope, e.g. "struct foo; void bar() { struct foo; }", just create a 2943 // new decl/type. We set PrevDecl to NULL so that the entities 2944 // have distinct types. 2945 PrevDecl = 0; 2946 } 2947 // If we get here, we're going to create a new Decl. If PrevDecl 2948 // is non-NULL, it's a definition of the tag declared by 2949 // PrevDecl. If it's NULL, we have a new definition. 2950 } else { 2951 // PrevDecl is a namespace. 2952 if (isDeclInScope(PrevDecl, DC, S)) { 2953 // The tag name clashes with a namespace name, issue an error and 2954 // recover by making this tag be anonymous. 2955 Diag(NameLoc, diag::err_redefinition_different_kind) << Name; 2956 Diag(PrevDecl->getLocation(), diag::note_previous_definition); 2957 Name = 0; 2958 PrevDecl = 0; 2959 } else { 2960 // The existing declaration isn't relevant to us; we're in a 2961 // new scope, so clear out the previous declaration. 2962 PrevDecl = 0; 2963 } 2964 } 2965 } 2966 2967CreateNewDecl: 2968 2969 // If there is an identifier, use the location of the identifier as the 2970 // location of the decl, otherwise use the location of the struct/union 2971 // keyword. 2972 SourceLocation Loc = NameLoc.isValid() ? NameLoc : KWLoc; 2973 2974 // Otherwise, create a new declaration. If there is a previous 2975 // declaration of the same entity, the two will be linked via 2976 // PrevDecl. 2977 TagDecl *New; 2978 2979 if (Kind == TagDecl::TK_enum) { 2980 // FIXME: Tag decls should be chained to any simultaneous vardecls, e.g.: 2981 // enum X { A, B, C } D; D should chain to X. 2982 New = EnumDecl::Create(Context, DC, Loc, Name, 2983 cast_or_null<EnumDecl>(PrevDecl)); 2984 // If this is an undefined enum, warn. 2985 if (TK != TK_Definition) Diag(Loc, diag::ext_forward_ref_enum); 2986 } else { 2987 // struct/union/class 2988 2989 // FIXME: Tag decls should be chained to any simultaneous vardecls, e.g.: 2990 // struct X { int A; } D; D should chain to X. 2991 if (getLangOptions().CPlusPlus) 2992 // FIXME: Look for a way to use RecordDecl for simple structs. 2993 New = CXXRecordDecl::Create(Context, Kind, DC, Loc, Name, 2994 cast_or_null<CXXRecordDecl>(PrevDecl)); 2995 else 2996 New = RecordDecl::Create(Context, Kind, DC, Loc, Name, 2997 cast_or_null<RecordDecl>(PrevDecl)); 2998 } 2999 3000 if (Kind != TagDecl::TK_enum) { 3001 // Handle #pragma pack: if the #pragma pack stack has non-default 3002 // alignment, make up a packed attribute for this decl. These 3003 // attributes are checked when the ASTContext lays out the 3004 // structure. 3005 // 3006 // It is important for implementing the correct semantics that this 3007 // happen here (in act on tag decl). The #pragma pack stack is 3008 // maintained as a result of parser callbacks which can occur at 3009 // many points during the parsing of a struct declaration (because 3010 // the #pragma tokens are effectively skipped over during the 3011 // parsing of the struct). 3012 if (unsigned Alignment = PackContext.getAlignment()) 3013 New->addAttr(new PackedAttr(Alignment * 8)); 3014 } 3015 3016 if (Attr) 3017 ProcessDeclAttributeList(New, Attr); 3018 3019 // Set the lexical context. If the tag has a C++ scope specifier, the 3020 // lexical context will be different from the semantic context. 3021 New->setLexicalDeclContext(CurContext); 3022 3023 // If this has an identifier, add it to the scope stack. 3024 if (Name) { 3025 // The scope passed in may not be a decl scope. Zip up the scope tree until 3026 // we find one that is. 3027 while ((S->getFlags() & Scope::DeclScope) == 0) 3028 S = S->getParent(); 3029 3030 // Add it to the decl chain. 3031 PushOnScopeChains(New, S); 3032 } else if (getLangOptions().CPlusPlus) { 3033 // FIXME: We also want to do this for C, but if this tag is 3034 // defined within a structure CurContext will point to the context 3035 // enclosing the structure, and we would end up inserting the tag 3036 // type into the wrong place. 3037 CurContext->addDecl(Context, New); 3038 } 3039 3040 return New; 3041} 3042 3043void Sema::ActOnTagStartDefinition(Scope *S, DeclTy *TagD) { 3044 TagDecl *Tag = cast<TagDecl>((Decl *)TagD); 3045 3046 // Enter the tag context. 3047 PushDeclContext(S, Tag); 3048 3049 if (CXXRecordDecl *Record = dyn_cast<CXXRecordDecl>(Tag)) { 3050 FieldCollector->StartClass(); 3051 3052 if (Record->getIdentifier()) { 3053 // C++ [class]p2: 3054 // [...] The class-name is also inserted into the scope of the 3055 // class itself; this is known as the injected-class-name. For 3056 // purposes of access checking, the injected-class-name is treated 3057 // as if it were a public member name. 3058 RecordDecl *InjectedClassName 3059 = CXXRecordDecl::Create(Context, Record->getTagKind(), 3060 CurContext, Record->getLocation(), 3061 Record->getIdentifier(), Record); 3062 InjectedClassName->setImplicit(); 3063 PushOnScopeChains(InjectedClassName, S); 3064 } 3065 } 3066} 3067 3068void Sema::ActOnTagFinishDefinition(Scope *S, DeclTy *TagD) { 3069 TagDecl *Tag = cast<TagDecl>((Decl *)TagD); 3070 3071 if (isa<CXXRecordDecl>(Tag)) 3072 FieldCollector->FinishClass(); 3073 3074 // Exit this scope of this tag's definition. 3075 PopDeclContext(); 3076 3077 // Notify the consumer that we've defined a tag. 3078 Consumer.HandleTagDeclDefinition(Tag); 3079} 3080 3081/// TryToFixInvalidVariablyModifiedType - Helper method to turn variable array 3082/// types into constant array types in certain situations which would otherwise 3083/// be errors (for GCC compatibility). 3084static QualType TryToFixInvalidVariablyModifiedType(QualType T, 3085 ASTContext &Context) { 3086 // This method tries to turn a variable array into a constant 3087 // array even when the size isn't an ICE. This is necessary 3088 // for compatibility with code that depends on gcc's buggy 3089 // constant expression folding, like struct {char x[(int)(char*)2];} 3090 const VariableArrayType* VLATy = dyn_cast<VariableArrayType>(T); 3091 if (!VLATy) return QualType(); 3092 3093 Expr::EvalResult EvalResult; 3094 if (!VLATy->getSizeExpr() || 3095 !VLATy->getSizeExpr()->Evaluate(EvalResult, Context)) 3096 return QualType(); 3097 3098 assert(EvalResult.Val.isInt() && "Size expressions must be integers!"); 3099 llvm::APSInt &Res = EvalResult.Val.getInt(); 3100 if (Res > llvm::APSInt(Res.getBitWidth(), Res.isUnsigned())) 3101 return Context.getConstantArrayType(VLATy->getElementType(), 3102 Res, ArrayType::Normal, 0); 3103 return QualType(); 3104} 3105 3106bool Sema::VerifyBitField(SourceLocation FieldLoc, IdentifierInfo *FieldName, 3107 QualType FieldTy, const Expr *BitWidth) { 3108 // FIXME: 6.7.2.1p4 - verify the field type. 3109 3110 llvm::APSInt Value; 3111 if (VerifyIntegerConstantExpression(BitWidth, &Value)) 3112 return true; 3113 3114 // Zero-width bitfield is ok for anonymous field. 3115 if (Value == 0 && FieldName) 3116 return Diag(FieldLoc, diag::err_bitfield_has_zero_width) << FieldName; 3117 3118 if (Value.isNegative()) 3119 return Diag(FieldLoc, diag::err_bitfield_has_negative_width) << FieldName; 3120 3121 uint64_t TypeSize = Context.getTypeSize(FieldTy); 3122 // FIXME: We won't need the 0 size once we check that the field type is valid. 3123 if (TypeSize && Value.getZExtValue() > TypeSize) 3124 return Diag(FieldLoc, diag::err_bitfield_width_exceeds_type_size) 3125 << FieldName << (unsigned)TypeSize; 3126 3127 return false; 3128} 3129 3130/// ActOnField - Each field of a struct/union/class is passed into this in order 3131/// to create a FieldDecl object for it. 3132Sema::DeclTy *Sema::ActOnField(Scope *S, DeclTy *TagD, 3133 SourceLocation DeclStart, 3134 Declarator &D, ExprTy *BitfieldWidth) { 3135 IdentifierInfo *II = D.getIdentifier(); 3136 Expr *BitWidth = (Expr*)BitfieldWidth; 3137 SourceLocation Loc = DeclStart; 3138 RecordDecl *Record = (RecordDecl *)TagD; 3139 if (II) Loc = D.getIdentifierLoc(); 3140 3141 // FIXME: Unnamed fields can be handled in various different ways, for 3142 // example, unnamed unions inject all members into the struct namespace! 3143 3144 QualType T = GetTypeForDeclarator(D, S); 3145 assert(!T.isNull() && "GetTypeForDeclarator() returned null type"); 3146 bool InvalidDecl = false; 3147 3148 // C99 6.7.2.1p8: A member of a structure or union may have any type other 3149 // than a variably modified type. 3150 if (T->isVariablyModifiedType()) { 3151 QualType FixedTy = TryToFixInvalidVariablyModifiedType(T, Context); 3152 if (!FixedTy.isNull()) { 3153 Diag(Loc, diag::warn_illegal_constant_array_size); 3154 T = FixedTy; 3155 } else { 3156 Diag(Loc, diag::err_typecheck_field_variable_size); 3157 T = Context.IntTy; 3158 InvalidDecl = true; 3159 } 3160 } 3161 3162 if (BitWidth) { 3163 if (VerifyBitField(Loc, II, T, BitWidth)) 3164 InvalidDecl = true; 3165 } else { 3166 // Not a bitfield. 3167 3168 // validate II. 3169 3170 } 3171 3172 // FIXME: Chain fielddecls together. 3173 FieldDecl *NewFD; 3174 3175 NewFD = FieldDecl::Create(Context, Record, 3176 Loc, II, T, BitWidth, 3177 D.getDeclSpec().getStorageClassSpec() == 3178 DeclSpec::SCS_mutable, 3179 /*PrevDecl=*/0); 3180 3181 if (II) { 3182 Decl *PrevDecl 3183 = LookupDecl(II, Decl::IDNS_Member, S, 0, false, false, false); 3184 if (PrevDecl && isDeclInScope(PrevDecl, CurContext, S) 3185 && !isa<TagDecl>(PrevDecl)) { 3186 Diag(Loc, diag::err_duplicate_member) << II; 3187 Diag(PrevDecl->getLocation(), diag::note_previous_declaration); 3188 NewFD->setInvalidDecl(); 3189 Record->setInvalidDecl(); 3190 } 3191 } 3192 3193 if (getLangOptions().CPlusPlus) { 3194 CheckExtraCXXDefaultArguments(D); 3195 if (!T->isPODType()) 3196 cast<CXXRecordDecl>(Record)->setPOD(false); 3197 } 3198 3199 ProcessDeclAttributes(NewFD, D); 3200 3201 if (D.getInvalidType() || InvalidDecl) 3202 NewFD->setInvalidDecl(); 3203 3204 if (II) { 3205 PushOnScopeChains(NewFD, S); 3206 } else 3207 Record->addDecl(Context, NewFD); 3208 3209 return NewFD; 3210} 3211 3212/// TranslateIvarVisibility - Translate visibility from a token ID to an 3213/// AST enum value. 3214static ObjCIvarDecl::AccessControl 3215TranslateIvarVisibility(tok::ObjCKeywordKind ivarVisibility) { 3216 switch (ivarVisibility) { 3217 default: assert(0 && "Unknown visitibility kind"); 3218 case tok::objc_private: return ObjCIvarDecl::Private; 3219 case tok::objc_public: return ObjCIvarDecl::Public; 3220 case tok::objc_protected: return ObjCIvarDecl::Protected; 3221 case tok::objc_package: return ObjCIvarDecl::Package; 3222 } 3223} 3224 3225/// ActOnIvar - Each ivar field of an objective-c class is passed into this 3226/// in order to create an IvarDecl object for it. 3227Sema::DeclTy *Sema::ActOnIvar(Scope *S, 3228 SourceLocation DeclStart, 3229 Declarator &D, ExprTy *BitfieldWidth, 3230 tok::ObjCKeywordKind Visibility) { 3231 3232 IdentifierInfo *II = D.getIdentifier(); 3233 Expr *BitWidth = (Expr*)BitfieldWidth; 3234 SourceLocation Loc = DeclStart; 3235 if (II) Loc = D.getIdentifierLoc(); 3236 3237 // FIXME: Unnamed fields can be handled in various different ways, for 3238 // example, unnamed unions inject all members into the struct namespace! 3239 3240 QualType T = GetTypeForDeclarator(D, S); 3241 assert(!T.isNull() && "GetTypeForDeclarator() returned null type"); 3242 bool InvalidDecl = false; 3243 3244 if (BitWidth) { 3245 // TODO: Validate. 3246 //printf("WARNING: BITFIELDS IGNORED!\n"); 3247 3248 // 6.7.2.1p3 3249 // 6.7.2.1p4 3250 3251 } else { 3252 // Not a bitfield. 3253 3254 // validate II. 3255 3256 } 3257 3258 // C99 6.7.2.1p8: A member of a structure or union may have any type other 3259 // than a variably modified type. 3260 if (T->isVariablyModifiedType()) { 3261 Diag(Loc, diag::err_typecheck_ivar_variable_size); 3262 InvalidDecl = true; 3263 } 3264 3265 // Get the visibility (access control) for this ivar. 3266 ObjCIvarDecl::AccessControl ac = 3267 Visibility != tok::objc_not_keyword ? TranslateIvarVisibility(Visibility) 3268 : ObjCIvarDecl::None; 3269 3270 // Construct the decl. 3271 ObjCIvarDecl *NewID = ObjCIvarDecl::Create(Context, Loc, II, T, ac, 3272 (Expr *)BitfieldWidth); 3273 3274 if (II) { 3275 Decl *PrevDecl 3276 = LookupDecl(II, Decl::IDNS_Member, S, 0, false, false, false); 3277 if (PrevDecl && isDeclInScope(PrevDecl, CurContext, S) 3278 && !isa<TagDecl>(PrevDecl)) { 3279 Diag(Loc, diag::err_duplicate_member) << II; 3280 Diag(PrevDecl->getLocation(), diag::note_previous_declaration); 3281 NewID->setInvalidDecl(); 3282 } 3283 } 3284 3285 // Process attributes attached to the ivar. 3286 ProcessDeclAttributes(NewID, D); 3287 3288 if (D.getInvalidType() || InvalidDecl) 3289 NewID->setInvalidDecl(); 3290 3291 if (II) { 3292 // FIXME: When interfaces are DeclContexts, we'll need to add 3293 // these to the interface. 3294 S->AddDecl(NewID); 3295 IdResolver.AddDecl(NewID); 3296 } 3297 3298 return NewID; 3299} 3300 3301void Sema::ActOnFields(Scope* S, 3302 SourceLocation RecLoc, DeclTy *RecDecl, 3303 DeclTy **Fields, unsigned NumFields, 3304 SourceLocation LBrac, SourceLocation RBrac, 3305 AttributeList *Attr) { 3306 Decl *EnclosingDecl = static_cast<Decl*>(RecDecl); 3307 assert(EnclosingDecl && "missing record or interface decl"); 3308 RecordDecl *Record = dyn_cast<RecordDecl>(EnclosingDecl); 3309 3310 if (Record) { 3311 QualType RecordType = Context.getTypeDeclType(Record); 3312 if (RecordType->getAsRecordType()->getDecl()->isDefinition()) { 3313 RecordDecl *Def = RecordType->getAsRecordType()->getDecl(); 3314 // Diagnose code like: 3315 // struct S { struct S {} X; }; 3316 // We discover this when we complete the outer S. Reject and ignore the 3317 // outer S. 3318 Diag(Def->getLocation(), diag::err_nested_redefinition) 3319 << Def->getDeclName(); 3320 Diag(RecLoc, diag::note_previous_definition); 3321 Record->setInvalidDecl(); 3322 return; 3323 } 3324 } 3325 3326 // Verify that all the fields are okay. 3327 unsigned NumNamedMembers = 0; 3328 llvm::SmallVector<FieldDecl*, 32> RecFields; 3329 3330 for (unsigned i = 0; i != NumFields; ++i) { 3331 FieldDecl *FD = cast_or_null<FieldDecl>(static_cast<Decl*>(Fields[i])); 3332 assert(FD && "missing field decl"); 3333 3334 // Get the type for the field. 3335 Type *FDTy = FD->getType().getTypePtr(); 3336 3337 if (!FD->isAnonymousStructOrUnion()) { 3338 // Remember all fields written by the user. 3339 RecFields.push_back(FD); 3340 } 3341 3342 // C99 6.7.2.1p2 - A field may not be a function type. 3343 if (FDTy->isFunctionType()) { 3344 Diag(FD->getLocation(), diag::err_field_declared_as_function) 3345 << FD->getDeclName(); 3346 FD->setInvalidDecl(); 3347 EnclosingDecl->setInvalidDecl(); 3348 continue; 3349 } 3350 // C99 6.7.2.1p2 - A field may not be an incomplete type except... 3351 if (FDTy->isIncompleteType()) { 3352 if (!Record) { // Incomplete ivar type is always an error. 3353 Diag(FD->getLocation(), diag::err_field_incomplete) <<FD->getDeclName(); 3354 FD->setInvalidDecl(); 3355 EnclosingDecl->setInvalidDecl(); 3356 continue; 3357 } 3358 if (i != NumFields-1 || // ... that the last member ... 3359 !Record->isStruct() || // ... of a structure ... 3360 !FDTy->isArrayType()) { //... may have incomplete array type. 3361 Diag(FD->getLocation(), diag::err_field_incomplete) <<FD->getDeclName(); 3362 FD->setInvalidDecl(); 3363 EnclosingDecl->setInvalidDecl(); 3364 continue; 3365 } 3366 if (NumNamedMembers < 1) { //... must have more than named member ... 3367 Diag(FD->getLocation(), diag::err_flexible_array_empty_struct) 3368 << FD->getDeclName(); 3369 FD->setInvalidDecl(); 3370 EnclosingDecl->setInvalidDecl(); 3371 continue; 3372 } 3373 // Okay, we have a legal flexible array member at the end of the struct. 3374 if (Record) 3375 Record->setHasFlexibleArrayMember(true); 3376 } 3377 /// C99 6.7.2.1p2 - a struct ending in a flexible array member cannot be the 3378 /// field of another structure or the element of an array. 3379 if (const RecordType *FDTTy = FDTy->getAsRecordType()) { 3380 if (FDTTy->getDecl()->hasFlexibleArrayMember()) { 3381 // If this is a member of a union, then entire union becomes "flexible". 3382 if (Record && Record->isUnion()) { 3383 Record->setHasFlexibleArrayMember(true); 3384 } else { 3385 // If this is a struct/class and this is not the last element, reject 3386 // it. Note that GCC supports variable sized arrays in the middle of 3387 // structures. 3388 if (i != NumFields-1) { 3389 Diag(FD->getLocation(), diag::err_variable_sized_type_in_struct) 3390 << FD->getDeclName(); 3391 FD->setInvalidDecl(); 3392 EnclosingDecl->setInvalidDecl(); 3393 continue; 3394 } 3395 // We support flexible arrays at the end of structs in other structs 3396 // as an extension. 3397 Diag(FD->getLocation(), diag::ext_flexible_array_in_struct) 3398 << FD->getDeclName(); 3399 if (Record) 3400 Record->setHasFlexibleArrayMember(true); 3401 } 3402 } 3403 } 3404 /// A field cannot be an Objective-c object 3405 if (FDTy->isObjCInterfaceType()) { 3406 Diag(FD->getLocation(), diag::err_statically_allocated_object) 3407 << FD->getDeclName(); 3408 FD->setInvalidDecl(); 3409 EnclosingDecl->setInvalidDecl(); 3410 continue; 3411 } 3412 // Keep track of the number of named members. 3413 if (FD->getIdentifier()) 3414 ++NumNamedMembers; 3415 } 3416 3417 // Okay, we successfully defined 'Record'. 3418 if (Record) { 3419 Record->completeDefinition(Context); 3420 } else { 3421 ObjCIvarDecl **ClsFields = reinterpret_cast<ObjCIvarDecl**>(&RecFields[0]); 3422 if (ObjCInterfaceDecl *ID = dyn_cast<ObjCInterfaceDecl>(EnclosingDecl)) { 3423 ID->addInstanceVariablesToClass(ClsFields, RecFields.size(), RBrac); 3424 // Must enforce the rule that ivars in the base classes may not be 3425 // duplicates. 3426 if (ID->getSuperClass()) { 3427 for (ObjCInterfaceDecl::ivar_iterator IVI = ID->ivar_begin(), 3428 IVE = ID->ivar_end(); IVI != IVE; ++IVI) { 3429 ObjCIvarDecl* Ivar = (*IVI); 3430 IdentifierInfo *II = Ivar->getIdentifier(); 3431 ObjCIvarDecl* prevIvar = ID->getSuperClass()->FindIvarDeclaration(II); 3432 if (prevIvar) { 3433 Diag(Ivar->getLocation(), diag::err_duplicate_member) << II; 3434 Diag(prevIvar->getLocation(), diag::note_previous_declaration); 3435 } 3436 } 3437 } 3438 } 3439 else if (ObjCImplementationDecl *IMPDecl = 3440 dyn_cast<ObjCImplementationDecl>(EnclosingDecl)) { 3441 assert(IMPDecl && "ActOnFields - missing ObjCImplementationDecl"); 3442 IMPDecl->ObjCAddInstanceVariablesToClassImpl(ClsFields, RecFields.size()); 3443 CheckImplementationIvars(IMPDecl, ClsFields, RecFields.size(), RBrac); 3444 } 3445 } 3446 3447 if (Attr) 3448 ProcessDeclAttributeList(Record, Attr); 3449} 3450 3451Sema::DeclTy *Sema::ActOnEnumConstant(Scope *S, DeclTy *theEnumDecl, 3452 DeclTy *lastEnumConst, 3453 SourceLocation IdLoc, IdentifierInfo *Id, 3454 SourceLocation EqualLoc, ExprTy *val) { 3455 EnumDecl *TheEnumDecl = cast<EnumDecl>(static_cast<Decl*>(theEnumDecl)); 3456 EnumConstantDecl *LastEnumConst = 3457 cast_or_null<EnumConstantDecl>(static_cast<Decl*>(lastEnumConst)); 3458 Expr *Val = static_cast<Expr*>(val); 3459 3460 // The scope passed in may not be a decl scope. Zip up the scope tree until 3461 // we find one that is. 3462 while ((S->getFlags() & Scope::DeclScope) == 0) 3463 S = S->getParent(); 3464 3465 // Verify that there isn't already something declared with this name in this 3466 // scope. 3467 Decl *PrevDecl = LookupDecl(Id, Decl::IDNS_Ordinary, S); 3468 if (PrevDecl && PrevDecl->isTemplateParameter()) { 3469 // Maybe we will complain about the shadowed template parameter. 3470 DiagnoseTemplateParameterShadow(IdLoc, PrevDecl); 3471 // Just pretend that we didn't see the previous declaration. 3472 PrevDecl = 0; 3473 } 3474 3475 if (PrevDecl) { 3476 // When in C++, we may get a TagDecl with the same name; in this case the 3477 // enum constant will 'hide' the tag. 3478 assert((getLangOptions().CPlusPlus || !isa<TagDecl>(PrevDecl)) && 3479 "Received TagDecl when not in C++!"); 3480 if (!isa<TagDecl>(PrevDecl) && isDeclInScope(PrevDecl, CurContext, S)) { 3481 if (isa<EnumConstantDecl>(PrevDecl)) 3482 Diag(IdLoc, diag::err_redefinition_of_enumerator) << Id; 3483 else 3484 Diag(IdLoc, diag::err_redefinition) << Id; 3485 Diag(PrevDecl->getLocation(), diag::note_previous_definition); 3486 delete Val; 3487 return 0; 3488 } 3489 } 3490 3491 llvm::APSInt EnumVal(32); 3492 QualType EltTy; 3493 if (Val) { 3494 // Make sure to promote the operand type to int. 3495 UsualUnaryConversions(Val); 3496 3497 // C99 6.7.2.2p2: Make sure we have an integer constant expression. 3498 SourceLocation ExpLoc; 3499 if (VerifyIntegerConstantExpression(Val, &EnumVal)) { 3500 delete Val; 3501 Val = 0; // Just forget about it. 3502 } else { 3503 EltTy = Val->getType(); 3504 } 3505 } 3506 3507 if (!Val) { 3508 if (LastEnumConst) { 3509 // Assign the last value + 1. 3510 EnumVal = LastEnumConst->getInitVal(); 3511 ++EnumVal; 3512 3513 // Check for overflow on increment. 3514 if (EnumVal < LastEnumConst->getInitVal()) 3515 Diag(IdLoc, diag::warn_enum_value_overflow); 3516 3517 EltTy = LastEnumConst->getType(); 3518 } else { 3519 // First value, set to zero. 3520 EltTy = Context.IntTy; 3521 EnumVal.zextOrTrunc(static_cast<uint32_t>(Context.getTypeSize(EltTy))); 3522 } 3523 } 3524 3525 EnumConstantDecl *New = 3526 EnumConstantDecl::Create(Context, TheEnumDecl, IdLoc, Id, EltTy, 3527 Val, EnumVal, 3528 LastEnumConst); 3529 3530 // Register this decl in the current scope stack. 3531 PushOnScopeChains(New, S); 3532 3533 // Add this enumerator into the enum itself. 3534 // FIXME: This means that the enumerator is stored in two 3535 // DeclContexts. This is not a long-term solution. 3536 New->setLexicalDeclContext(TheEnumDecl); 3537 TheEnumDecl->addDecl(Context, New, true); 3538 return New; 3539} 3540 3541// FIXME: For consistency with ActOnFields(), we should have the parser 3542// pass in the source location for the left/right braces. 3543void Sema::ActOnEnumBody(SourceLocation EnumLoc, DeclTy *EnumDeclX, 3544 DeclTy **Elements, unsigned NumElements) { 3545 EnumDecl *Enum = cast<EnumDecl>(static_cast<Decl*>(EnumDeclX)); 3546 QualType EnumType = Context.getTypeDeclType(Enum); 3547 3548 if (EnumType->getAsEnumType()->getDecl()->isDefinition()) { 3549 EnumDecl *Def = EnumType->getAsEnumType()->getDecl(); 3550 // Diagnose code like: 3551 // enum e0 { 3552 // E0 = sizeof(enum e0 { E1 }) 3553 // }; 3554 Diag(Def->getLocation(), diag::err_nested_redefinition) 3555 << Enum->getDeclName(); 3556 Diag(Enum->getLocation(), diag::note_previous_definition); 3557 Enum->setInvalidDecl(); 3558 return; 3559 } 3560 3561 // TODO: If the result value doesn't fit in an int, it must be a long or long 3562 // long value. ISO C does not support this, but GCC does as an extension, 3563 // emit a warning. 3564 unsigned IntWidth = Context.Target.getIntWidth(); 3565 3566 // Verify that all the values are okay, compute the size of the values, and 3567 // reverse the list. 3568 unsigned NumNegativeBits = 0; 3569 unsigned NumPositiveBits = 0; 3570 3571 // Keep track of whether all elements have type int. 3572 bool AllElementsInt = true; 3573 3574 EnumConstantDecl *EltList = 0; 3575 for (unsigned i = 0; i != NumElements; ++i) { 3576 EnumConstantDecl *ECD = 3577 cast_or_null<EnumConstantDecl>(static_cast<Decl*>(Elements[i])); 3578 if (!ECD) continue; // Already issued a diagnostic. 3579 3580 // If the enum value doesn't fit in an int, emit an extension warning. 3581 const llvm::APSInt &InitVal = ECD->getInitVal(); 3582 assert(InitVal.getBitWidth() >= IntWidth && 3583 "Should have promoted value to int"); 3584 if (InitVal.getBitWidth() > IntWidth) { 3585 llvm::APSInt V(InitVal); 3586 V.trunc(IntWidth); 3587 V.extend(InitVal.getBitWidth()); 3588 if (V != InitVal) 3589 Diag(ECD->getLocation(), diag::ext_enum_value_not_int) 3590 << InitVal.toString(10); 3591 } 3592 3593 // Keep track of the size of positive and negative values. 3594 if (InitVal.isUnsigned() || InitVal.isNonNegative()) 3595 NumPositiveBits = std::max(NumPositiveBits, 3596 (unsigned)InitVal.getActiveBits()); 3597 else 3598 NumNegativeBits = std::max(NumNegativeBits, 3599 (unsigned)InitVal.getMinSignedBits()); 3600 3601 // Keep track of whether every enum element has type int (very commmon). 3602 if (AllElementsInt) 3603 AllElementsInt = ECD->getType() == Context.IntTy; 3604 3605 ECD->setNextDeclarator(EltList); 3606 EltList = ECD; 3607 } 3608 3609 // Figure out the type that should be used for this enum. 3610 // FIXME: Support attribute(packed) on enums and -fshort-enums. 3611 QualType BestType; 3612 unsigned BestWidth; 3613 3614 if (NumNegativeBits) { 3615 // If there is a negative value, figure out the smallest integer type (of 3616 // int/long/longlong) that fits. 3617 if (NumNegativeBits <= IntWidth && NumPositiveBits < IntWidth) { 3618 BestType = Context.IntTy; 3619 BestWidth = IntWidth; 3620 } else { 3621 BestWidth = Context.Target.getLongWidth(); 3622 3623 if (NumNegativeBits <= BestWidth && NumPositiveBits < BestWidth) 3624 BestType = Context.LongTy; 3625 else { 3626 BestWidth = Context.Target.getLongLongWidth(); 3627 3628 if (NumNegativeBits > BestWidth || NumPositiveBits >= BestWidth) 3629 Diag(Enum->getLocation(), diag::warn_enum_too_large); 3630 BestType = Context.LongLongTy; 3631 } 3632 } 3633 } else { 3634 // If there is no negative value, figure out which of uint, ulong, ulonglong 3635 // fits. 3636 if (NumPositiveBits <= IntWidth) { 3637 BestType = Context.UnsignedIntTy; 3638 BestWidth = IntWidth; 3639 } else if (NumPositiveBits <= 3640 (BestWidth = Context.Target.getLongWidth())) { 3641 BestType = Context.UnsignedLongTy; 3642 } else { 3643 BestWidth = Context.Target.getLongLongWidth(); 3644 assert(NumPositiveBits <= BestWidth && 3645 "How could an initializer get larger than ULL?"); 3646 BestType = Context.UnsignedLongLongTy; 3647 } 3648 } 3649 3650 // Loop over all of the enumerator constants, changing their types to match 3651 // the type of the enum if needed. 3652 for (unsigned i = 0; i != NumElements; ++i) { 3653 EnumConstantDecl *ECD = 3654 cast_or_null<EnumConstantDecl>(static_cast<Decl*>(Elements[i])); 3655 if (!ECD) continue; // Already issued a diagnostic. 3656 3657 // Standard C says the enumerators have int type, but we allow, as an 3658 // extension, the enumerators to be larger than int size. If each 3659 // enumerator value fits in an int, type it as an int, otherwise type it the 3660 // same as the enumerator decl itself. This means that in "enum { X = 1U }" 3661 // that X has type 'int', not 'unsigned'. 3662 if (ECD->getType() == Context.IntTy) { 3663 // Make sure the init value is signed. 3664 llvm::APSInt IV = ECD->getInitVal(); 3665 IV.setIsSigned(true); 3666 ECD->setInitVal(IV); 3667 3668 if (getLangOptions().CPlusPlus) 3669 // C++ [dcl.enum]p4: Following the closing brace of an 3670 // enum-specifier, each enumerator has the type of its 3671 // enumeration. 3672 ECD->setType(EnumType); 3673 continue; // Already int type. 3674 } 3675 3676 // Determine whether the value fits into an int. 3677 llvm::APSInt InitVal = ECD->getInitVal(); 3678 bool FitsInInt; 3679 if (InitVal.isUnsigned() || !InitVal.isNegative()) 3680 FitsInInt = InitVal.getActiveBits() < IntWidth; 3681 else 3682 FitsInInt = InitVal.getMinSignedBits() <= IntWidth; 3683 3684 // If it fits into an integer type, force it. Otherwise force it to match 3685 // the enum decl type. 3686 QualType NewTy; 3687 unsigned NewWidth; 3688 bool NewSign; 3689 if (FitsInInt) { 3690 NewTy = Context.IntTy; 3691 NewWidth = IntWidth; 3692 NewSign = true; 3693 } else if (ECD->getType() == BestType) { 3694 // Already the right type! 3695 if (getLangOptions().CPlusPlus) 3696 // C++ [dcl.enum]p4: Following the closing brace of an 3697 // enum-specifier, each enumerator has the type of its 3698 // enumeration. 3699 ECD->setType(EnumType); 3700 continue; 3701 } else { 3702 NewTy = BestType; 3703 NewWidth = BestWidth; 3704 NewSign = BestType->isSignedIntegerType(); 3705 } 3706 3707 // Adjust the APSInt value. 3708 InitVal.extOrTrunc(NewWidth); 3709 InitVal.setIsSigned(NewSign); 3710 ECD->setInitVal(InitVal); 3711 3712 // Adjust the Expr initializer and type. 3713 ECD->setInitExpr(new ImplicitCastExpr(NewTy, ECD->getInitExpr(), 3714 /*isLvalue=*/false)); 3715 if (getLangOptions().CPlusPlus) 3716 // C++ [dcl.enum]p4: Following the closing brace of an 3717 // enum-specifier, each enumerator has the type of its 3718 // enumeration. 3719 ECD->setType(EnumType); 3720 else 3721 ECD->setType(NewTy); 3722 } 3723 3724 Enum->completeDefinition(Context, BestType); 3725} 3726 3727Sema::DeclTy *Sema::ActOnFileScopeAsmDecl(SourceLocation Loc, 3728 ExprArg expr) { 3729 StringLiteral *AsmString = cast<StringLiteral>((Expr*)expr.release()); 3730 3731 return FileScopeAsmDecl::Create(Context, Loc, AsmString); 3732} 3733 3734 3735void Sema::ActOnPragmaPack(PragmaPackKind Kind, IdentifierInfo *Name, 3736 ExprTy *alignment, SourceLocation PragmaLoc, 3737 SourceLocation LParenLoc, SourceLocation RParenLoc) { 3738 Expr *Alignment = static_cast<Expr *>(alignment); 3739 3740 // If specified then alignment must be a "small" power of two. 3741 unsigned AlignmentVal = 0; 3742 if (Alignment) { 3743 llvm::APSInt Val; 3744 if (!Alignment->isIntegerConstantExpr(Val, Context) || 3745 !Val.isPowerOf2() || 3746 Val.getZExtValue() > 16) { 3747 Diag(PragmaLoc, diag::warn_pragma_pack_invalid_alignment); 3748 delete Alignment; 3749 return; // Ignore 3750 } 3751 3752 AlignmentVal = (unsigned) Val.getZExtValue(); 3753 } 3754 3755 switch (Kind) { 3756 case Action::PPK_Default: // pack([n]) 3757 PackContext.setAlignment(AlignmentVal); 3758 break; 3759 3760 case Action::PPK_Show: // pack(show) 3761 // Show the current alignment, making sure to show the right value 3762 // for the default. 3763 AlignmentVal = PackContext.getAlignment(); 3764 // FIXME: This should come from the target. 3765 if (AlignmentVal == 0) 3766 AlignmentVal = 8; 3767 Diag(PragmaLoc, diag::warn_pragma_pack_show) << AlignmentVal; 3768 break; 3769 3770 case Action::PPK_Push: // pack(push [, id] [, [n]) 3771 PackContext.push(Name); 3772 // Set the new alignment if specified. 3773 if (Alignment) 3774 PackContext.setAlignment(AlignmentVal); 3775 break; 3776 3777 case Action::PPK_Pop: // pack(pop [, id] [, n]) 3778 // MSDN, C/C++ Preprocessor Reference > Pragma Directives > pack: 3779 // "#pragma pack(pop, identifier, n) is undefined" 3780 if (Alignment && Name) 3781 Diag(PragmaLoc, diag::warn_pragma_pack_pop_identifer_and_alignment); 3782 3783 // Do the pop. 3784 if (!PackContext.pop(Name)) { 3785 // If a name was specified then failure indicates the name 3786 // wasn't found. Otherwise failure indicates the stack was 3787 // empty. 3788 Diag(PragmaLoc, diag::warn_pragma_pack_pop_failed) 3789 << (Name ? "no record matching name" : "stack empty"); 3790 3791 // FIXME: Warn about popping named records as MSVC does. 3792 } else { 3793 // Pop succeeded, set the new alignment if specified. 3794 if (Alignment) 3795 PackContext.setAlignment(AlignmentVal); 3796 } 3797 break; 3798 3799 default: 3800 assert(0 && "Invalid #pragma pack kind."); 3801 } 3802} 3803 3804bool PragmaPackStack::pop(IdentifierInfo *Name) { 3805 if (Stack.empty()) 3806 return false; 3807 3808 // If name is empty just pop top. 3809 if (!Name) { 3810 Alignment = Stack.back().first; 3811 Stack.pop_back(); 3812 return true; 3813 } 3814 3815 // Otherwise, find the named record. 3816 for (unsigned i = Stack.size(); i != 0; ) { 3817 --i; 3818 if (Stack[i].second == Name) { 3819 // Found it, pop up to and including this record. 3820 Alignment = Stack[i].first; 3821 Stack.erase(Stack.begin() + i, Stack.end()); 3822 return true; 3823 } 3824 } 3825 3826 return false; 3827} 3828