SemaDecl.cpp revision a8cc8ce044e5d2589128f0c1a84e586cce743b27
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 // FIXME: This is hideous. We need to teach PushOnScopeChains to 445 // relate Scopes to DeclContexts, and probably eliminate CurContext 446 // entirely, but we're not there yet. 447 DeclContext *SavedContext = CurContext; 448 CurContext = Context.getTranslationUnitDecl(); 449 PushOnScopeChains(New, TUScope); 450 CurContext = SavedContext; 451 return New; 452} 453 454/// GetStdNamespace - This method gets the C++ "std" namespace. This is where 455/// everything from the standard library is defined. 456NamespaceDecl *Sema::GetStdNamespace() { 457 if (!StdNamespace) { 458 IdentifierInfo *StdIdent = &PP.getIdentifierTable().get("std"); 459 DeclContext *Global = Context.getTranslationUnitDecl(); 460 Decl *Std = LookupDecl(StdIdent, Decl::IDNS_Tag | Decl::IDNS_Ordinary, 461 0, Global, /*enableLazyBuiltinCreation=*/false); 462 StdNamespace = dyn_cast_or_null<NamespaceDecl>(Std); 463 } 464 return StdNamespace; 465} 466 467/// MergeTypeDefDecl - We just parsed a typedef 'New' which has the same name 468/// and scope as a previous declaration 'Old'. Figure out how to resolve this 469/// situation, merging decls or emitting diagnostics as appropriate. 470/// 471TypedefDecl *Sema::MergeTypeDefDecl(TypedefDecl *New, Decl *OldD) { 472 // Allow multiple definitions for ObjC built-in typedefs. 473 // FIXME: Verify the underlying types are equivalent! 474 if (getLangOptions().ObjC1) { 475 const IdentifierInfo *TypeID = New->getIdentifier(); 476 switch (TypeID->getLength()) { 477 default: break; 478 case 2: 479 if (!TypeID->isStr("id")) 480 break; 481 Context.setObjCIdType(New); 482 return New; 483 case 5: 484 if (!TypeID->isStr("Class")) 485 break; 486 Context.setObjCClassType(New); 487 return New; 488 case 3: 489 if (!TypeID->isStr("SEL")) 490 break; 491 Context.setObjCSelType(New); 492 return New; 493 case 8: 494 if (!TypeID->isStr("Protocol")) 495 break; 496 Context.setObjCProtoType(New->getUnderlyingType()); 497 return New; 498 } 499 // Fall through - the typedef name was not a builtin type. 500 } 501 // Verify the old decl was also a typedef. 502 TypedefDecl *Old = dyn_cast<TypedefDecl>(OldD); 503 if (!Old) { 504 Diag(New->getLocation(), diag::err_redefinition_different_kind) 505 << New->getDeclName(); 506 Diag(OldD->getLocation(), diag::note_previous_definition); 507 return New; 508 } 509 510 // If the typedef types are not identical, reject them in all languages and 511 // with any extensions enabled. 512 if (Old->getUnderlyingType() != New->getUnderlyingType() && 513 Context.getCanonicalType(Old->getUnderlyingType()) != 514 Context.getCanonicalType(New->getUnderlyingType())) { 515 Diag(New->getLocation(), diag::err_redefinition_different_typedef) 516 << New->getUnderlyingType() << Old->getUnderlyingType(); 517 Diag(Old->getLocation(), diag::note_previous_definition); 518 return Old; 519 } 520 521 if (getLangOptions().Microsoft) return New; 522 523 // C++ [dcl.typedef]p2: 524 // In a given non-class scope, a typedef specifier can be used to 525 // redefine the name of any type declared in that scope to refer 526 // to the type to which it already refers. 527 if (getLangOptions().CPlusPlus && !isa<CXXRecordDecl>(CurContext)) 528 return New; 529 530 // In C, redeclaration of a type is a constraint violation (6.7.2.3p1). 531 // Apparently GCC, Intel, and Sun all silently ignore the redeclaration if 532 // *either* declaration is in a system header. The code below implements 533 // this adhoc compatibility rule. FIXME: The following code will not 534 // work properly when compiling ".i" files (containing preprocessed output). 535 if (PP.getDiagnostics().getSuppressSystemWarnings()) { 536 SourceManager &SrcMgr = Context.getSourceManager(); 537 if (SrcMgr.isInSystemHeader(Old->getLocation())) 538 return New; 539 if (SrcMgr.isInSystemHeader(New->getLocation())) 540 return New; 541 } 542 543 Diag(New->getLocation(), diag::err_redefinition) << New->getDeclName(); 544 Diag(Old->getLocation(), diag::note_previous_definition); 545 return New; 546} 547 548/// DeclhasAttr - returns true if decl Declaration already has the target 549/// attribute. 550static bool DeclHasAttr(const Decl *decl, const Attr *target) { 551 for (const Attr *attr = decl->getAttrs(); attr; attr = attr->getNext()) 552 if (attr->getKind() == target->getKind()) 553 return true; 554 555 return false; 556} 557 558/// MergeAttributes - append attributes from the Old decl to the New one. 559static void MergeAttributes(Decl *New, Decl *Old) { 560 Attr *attr = const_cast<Attr*>(Old->getAttrs()), *tmp; 561 562 while (attr) { 563 tmp = attr; 564 attr = attr->getNext(); 565 566 if (!DeclHasAttr(New, tmp)) { 567 tmp->setInherited(true); 568 New->addAttr(tmp); 569 } else { 570 tmp->setNext(0); 571 delete(tmp); 572 } 573 } 574 575 Old->invalidateAttrs(); 576} 577 578/// MergeFunctionDecl - We just parsed a function 'New' from 579/// declarator D which has the same name and scope as a previous 580/// declaration 'Old'. Figure out how to resolve this situation, 581/// merging decls or emitting diagnostics as appropriate. 582/// Redeclaration will be set true if this New is a redeclaration OldD. 583/// 584/// In C++, New and Old must be declarations that are not 585/// overloaded. Use IsOverload to determine whether New and Old are 586/// overloaded, and to select the Old declaration that New should be 587/// merged with. 588FunctionDecl * 589Sema::MergeFunctionDecl(FunctionDecl *New, Decl *OldD, bool &Redeclaration) { 590 assert(!isa<OverloadedFunctionDecl>(OldD) && 591 "Cannot merge with an overloaded function declaration"); 592 593 Redeclaration = false; 594 // Verify the old decl was also a function. 595 FunctionDecl *Old = dyn_cast<FunctionDecl>(OldD); 596 if (!Old) { 597 Diag(New->getLocation(), diag::err_redefinition_different_kind) 598 << New->getDeclName(); 599 Diag(OldD->getLocation(), diag::note_previous_definition); 600 return New; 601 } 602 603 // Determine whether the previous declaration was a definition, 604 // implicit declaration, or a declaration. 605 diag::kind PrevDiag; 606 if (Old->isThisDeclarationADefinition()) 607 PrevDiag = diag::note_previous_definition; 608 else if (Old->isImplicit()) 609 PrevDiag = diag::note_previous_implicit_declaration; 610 else 611 PrevDiag = diag::note_previous_declaration; 612 613 QualType OldQType = Context.getCanonicalType(Old->getType()); 614 QualType NewQType = Context.getCanonicalType(New->getType()); 615 616 if (getLangOptions().CPlusPlus) { 617 // (C++98 13.1p2): 618 // Certain function declarations cannot be overloaded: 619 // -- Function declarations that differ only in the return type 620 // cannot be overloaded. 621 QualType OldReturnType 622 = cast<FunctionType>(OldQType.getTypePtr())->getResultType(); 623 QualType NewReturnType 624 = cast<FunctionType>(NewQType.getTypePtr())->getResultType(); 625 if (OldReturnType != NewReturnType) { 626 Diag(New->getLocation(), diag::err_ovl_diff_return_type); 627 Diag(Old->getLocation(), PrevDiag); 628 Redeclaration = true; 629 return New; 630 } 631 632 const CXXMethodDecl* OldMethod = dyn_cast<CXXMethodDecl>(Old); 633 const CXXMethodDecl* NewMethod = dyn_cast<CXXMethodDecl>(New); 634 if (OldMethod && NewMethod) { 635 // -- Member function declarations with the same name and the 636 // same parameter types cannot be overloaded if any of them 637 // is a static member function declaration. 638 if (OldMethod->isStatic() || NewMethod->isStatic()) { 639 Diag(New->getLocation(), diag::err_ovl_static_nonstatic_member); 640 Diag(Old->getLocation(), PrevDiag); 641 return New; 642 } 643 644 // C++ [class.mem]p1: 645 // [...] A member shall not be declared twice in the 646 // member-specification, except that a nested class or member 647 // class template can be declared and then later defined. 648 if (OldMethod->getLexicalDeclContext() == 649 NewMethod->getLexicalDeclContext()) { 650 unsigned NewDiag; 651 if (isa<CXXConstructorDecl>(OldMethod)) 652 NewDiag = diag::err_constructor_redeclared; 653 else if (isa<CXXDestructorDecl>(NewMethod)) 654 NewDiag = diag::err_destructor_redeclared; 655 else if (isa<CXXConversionDecl>(NewMethod)) 656 NewDiag = diag::err_conv_function_redeclared; 657 else 658 NewDiag = diag::err_member_redeclared; 659 660 Diag(New->getLocation(), NewDiag); 661 Diag(Old->getLocation(), PrevDiag); 662 } 663 } 664 665 // (C++98 8.3.5p3): 666 // All declarations for a function shall agree exactly in both the 667 // return type and the parameter-type-list. 668 if (OldQType == NewQType) { 669 // We have a redeclaration. 670 MergeAttributes(New, Old); 671 Redeclaration = true; 672 return MergeCXXFunctionDecl(New, Old); 673 } 674 675 // Fall through for conflicting redeclarations and redefinitions. 676 } 677 678 // C: Function types need to be compatible, not identical. This handles 679 // duplicate function decls like "void f(int); void f(enum X);" properly. 680 if (!getLangOptions().CPlusPlus && 681 Context.typesAreCompatible(OldQType, NewQType)) { 682 MergeAttributes(New, Old); 683 Redeclaration = true; 684 return New; 685 } 686 687 // A function that has already been declared has been redeclared or defined 688 // with a different type- show appropriate diagnostic 689 690 // TODO: CHECK FOR CONFLICTS, multiple decls with same name in one scope. 691 // TODO: This is totally simplistic. It should handle merging functions 692 // together etc, merging extern int X; int X; ... 693 Diag(New->getLocation(), diag::err_conflicting_types) << New->getDeclName(); 694 Diag(Old->getLocation(), PrevDiag); 695 return New; 696} 697 698/// Predicate for C "tentative" external object definitions (C99 6.9.2). 699static bool isTentativeDefinition(VarDecl *VD) { 700 if (VD->isFileVarDecl()) 701 return (!VD->getInit() && 702 (VD->getStorageClass() == VarDecl::None || 703 VD->getStorageClass() == VarDecl::Static)); 704 return false; 705} 706 707/// CheckForFileScopedRedefinitions - Make sure we forgo redefinition errors 708/// when dealing with C "tentative" external object definitions (C99 6.9.2). 709void Sema::CheckForFileScopedRedefinitions(Scope *S, VarDecl *VD) { 710 bool VDIsTentative = isTentativeDefinition(VD); 711 bool VDIsIncompleteArray = VD->getType()->isIncompleteArrayType(); 712 713 // FIXME: I don't think this will actually see all of the 714 // redefinitions. Can't we check this property on-the-fly? 715 for (IdentifierResolver::iterator 716 I = IdResolver.begin(VD->getIdentifier(), 717 VD->getDeclContext(), false/*LookInParentCtx*/), 718 E = IdResolver.end(); I != E; ++I) { 719 if (*I != VD && isDeclInScope(*I, VD->getDeclContext(), S)) { 720 VarDecl *OldDecl = dyn_cast<VarDecl>(*I); 721 722 // Handle the following case: 723 // int a[10]; 724 // int a[]; - the code below makes sure we set the correct type. 725 // int a[11]; - this is an error, size isn't 10. 726 if (OldDecl && VDIsTentative && VDIsIncompleteArray && 727 OldDecl->getType()->isConstantArrayType()) 728 VD->setType(OldDecl->getType()); 729 730 // Check for "tentative" definitions. We can't accomplish this in 731 // MergeVarDecl since the initializer hasn't been attached. 732 if (!OldDecl || isTentativeDefinition(OldDecl) || VDIsTentative) 733 continue; 734 735 // Handle __private_extern__ just like extern. 736 if (OldDecl->getStorageClass() != VarDecl::Extern && 737 OldDecl->getStorageClass() != VarDecl::PrivateExtern && 738 VD->getStorageClass() != VarDecl::Extern && 739 VD->getStorageClass() != VarDecl::PrivateExtern) { 740 Diag(VD->getLocation(), diag::err_redefinition) << VD->getDeclName(); 741 Diag(OldDecl->getLocation(), diag::note_previous_definition); 742 } 743 } 744 } 745} 746 747/// MergeVarDecl - We just parsed a variable 'New' which has the same name 748/// and scope as a previous declaration 'Old'. Figure out how to resolve this 749/// situation, merging decls or emitting diagnostics as appropriate. 750/// 751/// Tentative definition rules (C99 6.9.2p2) are checked by 752/// FinalizeDeclaratorGroup. Unfortunately, we can't analyze tentative 753/// definitions here, since the initializer hasn't been attached. 754/// 755VarDecl *Sema::MergeVarDecl(VarDecl *New, Decl *OldD) { 756 // Verify the old decl was also a variable. 757 VarDecl *Old = dyn_cast<VarDecl>(OldD); 758 if (!Old) { 759 Diag(New->getLocation(), diag::err_redefinition_different_kind) 760 << New->getDeclName(); 761 Diag(OldD->getLocation(), diag::note_previous_definition); 762 return New; 763 } 764 765 MergeAttributes(New, Old); 766 767 // Verify the types match. 768 QualType OldCType = Context.getCanonicalType(Old->getType()); 769 QualType NewCType = Context.getCanonicalType(New->getType()); 770 if (OldCType != NewCType && !Context.typesAreCompatible(OldCType, NewCType)) { 771 Diag(New->getLocation(), diag::err_redefinition) << New->getDeclName(); 772 Diag(Old->getLocation(), diag::note_previous_definition); 773 return New; 774 } 775 // C99 6.2.2p4: Check if we have a static decl followed by a non-static. 776 if (New->getStorageClass() == VarDecl::Static && 777 (Old->getStorageClass() == VarDecl::None || 778 Old->getStorageClass() == VarDecl::Extern)) { 779 Diag(New->getLocation(), diag::err_static_non_static) << New->getDeclName(); 780 Diag(Old->getLocation(), diag::note_previous_definition); 781 return New; 782 } 783 // C99 6.2.2p4: Check if we have a non-static decl followed by a static. 784 if (New->getStorageClass() != VarDecl::Static && 785 Old->getStorageClass() == VarDecl::Static) { 786 Diag(New->getLocation(), diag::err_non_static_static) << New->getDeclName(); 787 Diag(Old->getLocation(), diag::note_previous_definition); 788 return New; 789 } 790 // Variables with external linkage are analyzed in FinalizeDeclaratorGroup. 791 if (New->getStorageClass() != VarDecl::Extern && !New->isFileVarDecl()) { 792 Diag(New->getLocation(), diag::err_redefinition) << New->getDeclName(); 793 Diag(Old->getLocation(), diag::note_previous_definition); 794 } 795 return New; 796} 797 798/// CheckParmsForFunctionDef - Check that the parameters of the given 799/// function are appropriate for the definition of a function. This 800/// takes care of any checks that cannot be performed on the 801/// declaration itself, e.g., that the types of each of the function 802/// parameters are complete. 803bool Sema::CheckParmsForFunctionDef(FunctionDecl *FD) { 804 bool HasInvalidParm = false; 805 for (unsigned p = 0, NumParams = FD->getNumParams(); p < NumParams; ++p) { 806 ParmVarDecl *Param = FD->getParamDecl(p); 807 808 // C99 6.7.5.3p4: the parameters in a parameter type list in a 809 // function declarator that is part of a function definition of 810 // that function shall not have incomplete type. 811 if (Param->getType()->isIncompleteType() && 812 !Param->isInvalidDecl()) { 813 Diag(Param->getLocation(), diag::err_typecheck_decl_incomplete_type) 814 << Param->getType(); 815 Param->setInvalidDecl(); 816 HasInvalidParm = true; 817 } 818 819 // C99 6.9.1p5: If the declarator includes a parameter type list, the 820 // declaration of each parameter shall include an identifier. 821 if (Param->getIdentifier() == 0 && !getLangOptions().CPlusPlus) 822 Diag(Param->getLocation(), diag::err_parameter_name_omitted); 823 } 824 825 return HasInvalidParm; 826} 827 828/// ParsedFreeStandingDeclSpec - This method is invoked when a declspec with 829/// no declarator (e.g. "struct foo;") is parsed. 830Sema::DeclTy *Sema::ParsedFreeStandingDeclSpec(Scope *S, DeclSpec &DS) { 831 // FIXME: Isn't that more of a parser diagnostic than a sema diagnostic? 832 if (!DS.isMissingDeclaratorOk()) { 833 // FIXME: This diagnostic is emitted even when various previous 834 // errors occurred (see e.g. test/Sema/decl-invalid.c). However, 835 // DeclSpec has no means of communicating this information, and the 836 // responsible parser functions are quite far apart. 837 Diag(DS.getSourceRange().getBegin(), diag::err_no_declarators) 838 << DS.getSourceRange(); 839 return 0; 840 } 841 842 TagDecl *Tag 843 = dyn_cast_or_null<TagDecl>(static_cast<Decl *>(DS.getTypeRep())); 844 if (RecordDecl *Record = dyn_cast_or_null<RecordDecl>(Tag)) { 845 if (!Record->getDeclName() && Record->isDefinition() && 846 !Record->isInvalidDecl()) 847 return BuildAnonymousStructOrUnion(S, DS, Record); 848 } 849 850 return Tag; 851} 852 853/// InjectAnonymousStructOrUnionMembers - Inject the members of the 854/// anonymous struct or union AnonRecord into the owning context Owner 855/// and scope S. This routine will be invoked just after we realize 856/// that an unnamed union or struct is actually an anonymous union or 857/// struct, e.g., 858/// 859/// @code 860/// union { 861/// int i; 862/// float f; 863/// }; // InjectAnonymousStructOrUnionMembers called here to inject i and 864/// // f into the surrounding scope.x 865/// @endcode 866/// 867/// This routine is recursive, injecting the names of nested anonymous 868/// structs/unions into the owning context and scope as well. 869bool Sema::InjectAnonymousStructOrUnionMembers(Scope *S, DeclContext *Owner, 870 RecordDecl *AnonRecord) { 871 bool Invalid = false; 872 for (RecordDecl::field_iterator F = AnonRecord->field_begin(), 873 FEnd = AnonRecord->field_end(); 874 F != FEnd; ++F) { 875 if ((*F)->getDeclName()) { 876 Decl *PrevDecl = LookupDecl((*F)->getDeclName(), Decl::IDNS_Ordinary, 877 S, Owner, false, false, false); 878 if (PrevDecl && !isa<TagDecl>(PrevDecl)) { 879 // C++ [class.union]p2: 880 // The names of the members of an anonymous union shall be 881 // distinct from the names of any other entity in the 882 // scope in which the anonymous union is declared. 883 unsigned diagKind 884 = AnonRecord->isUnion()? diag::err_anonymous_union_member_redecl 885 : diag::err_anonymous_struct_member_redecl; 886 Diag((*F)->getLocation(), diagKind) 887 << (*F)->getDeclName(); 888 Diag(PrevDecl->getLocation(), diag::note_previous_declaration); 889 Invalid = true; 890 } else { 891 // C++ [class.union]p2: 892 // For the purpose of name lookup, after the anonymous union 893 // definition, the members of the anonymous union are 894 // considered to have been defined in the scope in which the 895 // anonymous union is declared. 896 Owner->insert(Context, *F); 897 S->AddDecl(*F); 898 IdResolver.AddDecl(*F); 899 } 900 } else if (const RecordType *InnerRecordType 901 = (*F)->getType()->getAsRecordType()) { 902 RecordDecl *InnerRecord = InnerRecordType->getDecl(); 903 if (InnerRecord->isAnonymousStructOrUnion()) 904 Invalid = Invalid || 905 InjectAnonymousStructOrUnionMembers(S, Owner, InnerRecord); 906 } 907 } 908 909 return Invalid; 910} 911 912/// ActOnAnonymousStructOrUnion - Handle the declaration of an 913/// anonymous structure or union. Anonymous unions are a C++ feature 914/// (C++ [class.union]) and a GNU C extension; anonymous structures 915/// are a GNU C and GNU C++ extension. 916Sema::DeclTy *Sema::BuildAnonymousStructOrUnion(Scope *S, DeclSpec &DS, 917 RecordDecl *Record) { 918 DeclContext *Owner = Record->getDeclContext(); 919 920 // Diagnose whether this anonymous struct/union is an extension. 921 if (Record->isUnion() && !getLangOptions().CPlusPlus) 922 Diag(Record->getLocation(), diag::ext_anonymous_union); 923 else if (!Record->isUnion()) 924 Diag(Record->getLocation(), diag::ext_anonymous_struct); 925 926 // C and C++ require different kinds of checks for anonymous 927 // structs/unions. 928 bool Invalid = false; 929 if (getLangOptions().CPlusPlus) { 930 const char* PrevSpec = 0; 931 // C++ [class.union]p3: 932 // Anonymous unions declared in a named namespace or in the 933 // global namespace shall be declared static. 934 if (DS.getStorageClassSpec() != DeclSpec::SCS_static && 935 (isa<TranslationUnitDecl>(Owner) || 936 (isa<NamespaceDecl>(Owner) && 937 cast<NamespaceDecl>(Owner)->getDeclName()))) { 938 Diag(Record->getLocation(), diag::err_anonymous_union_not_static); 939 Invalid = true; 940 941 // Recover by adding 'static'. 942 DS.SetStorageClassSpec(DeclSpec::SCS_static, SourceLocation(), PrevSpec); 943 } 944 // C++ [class.union]p3: 945 // A storage class is not allowed in a declaration of an 946 // anonymous union in a class scope. 947 else if (DS.getStorageClassSpec() != DeclSpec::SCS_unspecified && 948 isa<RecordDecl>(Owner)) { 949 Diag(DS.getStorageClassSpecLoc(), 950 diag::err_anonymous_union_with_storage_spec); 951 Invalid = true; 952 953 // Recover by removing the storage specifier. 954 DS.SetStorageClassSpec(DeclSpec::SCS_unspecified, SourceLocation(), 955 PrevSpec); 956 } 957 958 // C++ [class.union]p2: 959 // The member-specification of an anonymous union shall only 960 // define non-static data members. [Note: nested types and 961 // functions cannot be declared within an anonymous union. ] 962 for (DeclContext::decl_iterator Mem = Record->decls_begin(), 963 MemEnd = Record->decls_end(); 964 Mem != MemEnd; ++Mem) { 965 if (FieldDecl *FD = dyn_cast<FieldDecl>(*Mem)) { 966 // C++ [class.union]p3: 967 // An anonymous union shall not have private or protected 968 // members (clause 11). 969 if (FD->getAccess() == AS_protected || FD->getAccess() == AS_private) { 970 Diag(FD->getLocation(), diag::err_anonymous_record_nonpublic_member) 971 << (int)Record->isUnion() << (int)(FD->getAccess() == AS_protected); 972 Invalid = true; 973 } 974 } else if ((*Mem)->isImplicit()) { 975 // Any implicit members are fine. 976 } else if (RecordDecl *MemRecord = dyn_cast<RecordDecl>(*Mem)) { 977 if (!MemRecord->isAnonymousStructOrUnion() && 978 MemRecord->getDeclName()) { 979 // This is a nested type declaration. 980 Diag(MemRecord->getLocation(), diag::err_anonymous_record_with_type) 981 << (int)Record->isUnion(); 982 Invalid = true; 983 } 984 } else { 985 // We have something that isn't a non-static data 986 // member. Complain about it. 987 unsigned DK = diag::err_anonymous_record_bad_member; 988 if (isa<TypeDecl>(*Mem)) 989 DK = diag::err_anonymous_record_with_type; 990 else if (isa<FunctionDecl>(*Mem)) 991 DK = diag::err_anonymous_record_with_function; 992 else if (isa<VarDecl>(*Mem)) 993 DK = diag::err_anonymous_record_with_static; 994 Diag((*Mem)->getLocation(), DK) 995 << (int)Record->isUnion(); 996 Invalid = true; 997 } 998 } 999 } else { 1000 // FIXME: Check GNU C semantics 1001 } 1002 1003 if (!Record->isUnion() && !Owner->isRecord()) { 1004 Diag(Record->getLocation(), diag::err_anonymous_struct_not_member); 1005 Invalid = true; 1006 } 1007 1008 // Create a declaration for this anonymous struct/union. 1009 ScopedDecl *Anon = 0; 1010 if (RecordDecl *OwningClass = dyn_cast<RecordDecl>(Owner)) { 1011 Anon = FieldDecl::Create(Context, OwningClass, Record->getLocation(), 1012 /*IdentifierInfo=*/0, 1013 Context.getTypeDeclType(Record), 1014 /*BitWidth=*/0, /*Mutable=*/false, 1015 /*PrevDecl=*/0); 1016 Anon->setAccess(AS_public); 1017 if (getLangOptions().CPlusPlus) 1018 FieldCollector->Add(cast<FieldDecl>(Anon)); 1019 } else { 1020 VarDecl::StorageClass SC; 1021 switch (DS.getStorageClassSpec()) { 1022 default: assert(0 && "Unknown storage class!"); 1023 case DeclSpec::SCS_unspecified: SC = VarDecl::None; break; 1024 case DeclSpec::SCS_extern: SC = VarDecl::Extern; break; 1025 case DeclSpec::SCS_static: SC = VarDecl::Static; break; 1026 case DeclSpec::SCS_auto: SC = VarDecl::Auto; break; 1027 case DeclSpec::SCS_register: SC = VarDecl::Register; break; 1028 case DeclSpec::SCS_private_extern: SC = VarDecl::PrivateExtern; break; 1029 case DeclSpec::SCS_mutable: 1030 // mutable can only appear on non-static class members, so it's always 1031 // an error here 1032 Diag(Record->getLocation(), diag::err_mutable_nonmember); 1033 Invalid = true; 1034 SC = VarDecl::None; 1035 break; 1036 } 1037 1038 Anon = VarDecl::Create(Context, Owner, Record->getLocation(), 1039 /*IdentifierInfo=*/0, 1040 Context.getTypeDeclType(Record), 1041 SC, /*FIXME:LastDeclarator=*/0, 1042 DS.getSourceRange().getBegin()); 1043 } 1044 Anon->setImplicit(); 1045 1046 // Add the anonymous struct/union object to the current 1047 // context. We'll be referencing this object when we refer to one of 1048 // its members. 1049 Owner->addDecl(Context, Anon); 1050 1051 // Inject the members of the anonymous struct/union into the owning 1052 // context and into the identifier resolver chain for name lookup 1053 // purposes. 1054 Invalid = Invalid || InjectAnonymousStructOrUnionMembers(S, Owner, Record); 1055 1056 // Mark this as an anonymous struct/union type. Note that we do not 1057 // do this until after we have already checked and injected the 1058 // members of this anonymous struct/union type, because otherwise 1059 // the members could be injected twice: once by DeclContext when it 1060 // builds its lookup table, and once by 1061 // InjectAnonymousStructOrUnionMembers. 1062 Record->setAnonymousStructOrUnion(true); 1063 1064 if (Invalid) 1065 Anon->setInvalidDecl(); 1066 1067 return Anon; 1068} 1069 1070bool Sema::CheckSingleInitializer(Expr *&Init, QualType DeclType) { 1071 // Get the type before calling CheckSingleAssignmentConstraints(), since 1072 // it can promote the expression. 1073 QualType InitType = Init->getType(); 1074 1075 if (getLangOptions().CPlusPlus) 1076 return PerformCopyInitialization(Init, DeclType, "initializing"); 1077 1078 AssignConvertType ConvTy = CheckSingleAssignmentConstraints(DeclType, Init); 1079 return DiagnoseAssignmentResult(ConvTy, Init->getLocStart(), DeclType, 1080 InitType, Init, "initializing"); 1081} 1082 1083bool Sema::CheckStringLiteralInit(StringLiteral *strLiteral, QualType &DeclT) { 1084 const ArrayType *AT = Context.getAsArrayType(DeclT); 1085 1086 if (const IncompleteArrayType *IAT = dyn_cast<IncompleteArrayType>(AT)) { 1087 // C99 6.7.8p14. We have an array of character type with unknown size 1088 // being initialized to a string literal. 1089 llvm::APSInt ConstVal(32); 1090 ConstVal = strLiteral->getByteLength() + 1; 1091 // Return a new array type (C99 6.7.8p22). 1092 DeclT = Context.getConstantArrayType(IAT->getElementType(), ConstVal, 1093 ArrayType::Normal, 0); 1094 } else { 1095 const ConstantArrayType *CAT = cast<ConstantArrayType>(AT); 1096 // C99 6.7.8p14. We have an array of character type with known size. 1097 // FIXME: Avoid truncation for 64-bit length strings. 1098 if (strLiteral->getByteLength() > (unsigned)CAT->getSize().getZExtValue()) 1099 Diag(strLiteral->getSourceRange().getBegin(), 1100 diag::warn_initializer_string_for_char_array_too_long) 1101 << strLiteral->getSourceRange(); 1102 } 1103 // Set type from "char *" to "constant array of char". 1104 strLiteral->setType(DeclT); 1105 // For now, we always return false (meaning success). 1106 return false; 1107} 1108 1109StringLiteral *Sema::IsStringLiteralInit(Expr *Init, QualType DeclType) { 1110 const ArrayType *AT = Context.getAsArrayType(DeclType); 1111 if (AT && AT->getElementType()->isCharType()) { 1112 return dyn_cast<StringLiteral>(Init); 1113 } 1114 return 0; 1115} 1116 1117bool Sema::CheckInitializerTypes(Expr *&Init, QualType &DeclType, 1118 SourceLocation InitLoc, 1119 DeclarationName InitEntity) { 1120 if (DeclType->isDependentType() || Init->isTypeDependent()) 1121 return false; 1122 1123 // C++ [dcl.init.ref]p1: 1124 // A variable declared to be a T&, that is "reference to type T" 1125 // (8.3.2), shall be initialized by an object, or function, of 1126 // type T or by an object that can be converted into a T. 1127 if (DeclType->isReferenceType()) 1128 return CheckReferenceInit(Init, DeclType); 1129 1130 // C99 6.7.8p3: The type of the entity to be initialized shall be an array 1131 // of unknown size ("[]") or an object type that is not a variable array type. 1132 if (const VariableArrayType *VAT = Context.getAsVariableArrayType(DeclType)) 1133 return Diag(InitLoc, diag::err_variable_object_no_init) 1134 << VAT->getSizeExpr()->getSourceRange(); 1135 1136 InitListExpr *InitList = dyn_cast<InitListExpr>(Init); 1137 if (!InitList) { 1138 // FIXME: Handle wide strings 1139 if (StringLiteral *strLiteral = IsStringLiteralInit(Init, DeclType)) 1140 return CheckStringLiteralInit(strLiteral, DeclType); 1141 1142 // C++ [dcl.init]p14: 1143 // -- If the destination type is a (possibly cv-qualified) class 1144 // type: 1145 if (getLangOptions().CPlusPlus && DeclType->isRecordType()) { 1146 QualType DeclTypeC = Context.getCanonicalType(DeclType); 1147 QualType InitTypeC = Context.getCanonicalType(Init->getType()); 1148 1149 // -- If the initialization is direct-initialization, or if it is 1150 // copy-initialization where the cv-unqualified version of the 1151 // source type is the same class as, or a derived class of, the 1152 // class of the destination, constructors are considered. 1153 if ((DeclTypeC.getUnqualifiedType() == InitTypeC.getUnqualifiedType()) || 1154 IsDerivedFrom(InitTypeC, DeclTypeC)) { 1155 CXXConstructorDecl *Constructor 1156 = PerformInitializationByConstructor(DeclType, &Init, 1, 1157 InitLoc, Init->getSourceRange(), 1158 InitEntity, IK_Copy); 1159 return Constructor == 0; 1160 } 1161 1162 // -- Otherwise (i.e., for the remaining copy-initialization 1163 // cases), user-defined conversion sequences that can 1164 // convert from the source type to the destination type or 1165 // (when a conversion function is used) to a derived class 1166 // thereof are enumerated as described in 13.3.1.4, and the 1167 // best one is chosen through overload resolution 1168 // (13.3). If the conversion cannot be done or is 1169 // ambiguous, the initialization is ill-formed. The 1170 // function selected is called with the initializer 1171 // expression as its argument; if the function is a 1172 // constructor, the call initializes a temporary of the 1173 // destination type. 1174 // FIXME: We're pretending to do copy elision here; return to 1175 // this when we have ASTs for such things. 1176 if (!PerformImplicitConversion(Init, DeclType, "initializing")) 1177 return false; 1178 1179 if (InitEntity) 1180 return Diag(InitLoc, diag::err_cannot_initialize_decl) 1181 << InitEntity << (int)(Init->isLvalue(Context) == Expr::LV_Valid) 1182 << Init->getType() << Init->getSourceRange(); 1183 else 1184 return Diag(InitLoc, diag::err_cannot_initialize_decl_noname) 1185 << DeclType << (int)(Init->isLvalue(Context) == Expr::LV_Valid) 1186 << Init->getType() << Init->getSourceRange(); 1187 } 1188 1189 // C99 6.7.8p16. 1190 if (DeclType->isArrayType()) 1191 return Diag(Init->getLocStart(), diag::err_array_init_list_required) 1192 << Init->getSourceRange(); 1193 1194 return CheckSingleInitializer(Init, DeclType); 1195 } else if (getLangOptions().CPlusPlus) { 1196 // C++ [dcl.init]p14: 1197 // [...] If the class is an aggregate (8.5.1), and the initializer 1198 // is a brace-enclosed list, see 8.5.1. 1199 // 1200 // Note: 8.5.1 is handled below; here, we diagnose the case where 1201 // we have an initializer list and a destination type that is not 1202 // an aggregate. 1203 // FIXME: In C++0x, this is yet another form of initialization. 1204 if (const RecordType *ClassRec = DeclType->getAsRecordType()) { 1205 const CXXRecordDecl *ClassDecl = cast<CXXRecordDecl>(ClassRec->getDecl()); 1206 if (!ClassDecl->isAggregate()) 1207 return Diag(InitLoc, diag::err_init_non_aggr_init_list) 1208 << DeclType << Init->getSourceRange(); 1209 } 1210 } 1211 1212 InitListChecker CheckInitList(this, InitList, DeclType); 1213 return CheckInitList.HadError(); 1214} 1215 1216/// GetNameForDeclarator - Determine the full declaration name for the 1217/// given Declarator. 1218DeclarationName Sema::GetNameForDeclarator(Declarator &D) { 1219 switch (D.getKind()) { 1220 case Declarator::DK_Abstract: 1221 assert(D.getIdentifier() == 0 && "abstract declarators have no name"); 1222 return DeclarationName(); 1223 1224 case Declarator::DK_Normal: 1225 assert (D.getIdentifier() != 0 && "normal declarators have an identifier"); 1226 return DeclarationName(D.getIdentifier()); 1227 1228 case Declarator::DK_Constructor: { 1229 QualType Ty = Context.getTypeDeclType((TypeDecl *)D.getDeclaratorIdType()); 1230 Ty = Context.getCanonicalType(Ty); 1231 return Context.DeclarationNames.getCXXConstructorName(Ty); 1232 } 1233 1234 case Declarator::DK_Destructor: { 1235 QualType Ty = Context.getTypeDeclType((TypeDecl *)D.getDeclaratorIdType()); 1236 Ty = Context.getCanonicalType(Ty); 1237 return Context.DeclarationNames.getCXXDestructorName(Ty); 1238 } 1239 1240 case Declarator::DK_Conversion: { 1241 QualType Ty = QualType::getFromOpaquePtr(D.getDeclaratorIdType()); 1242 Ty = Context.getCanonicalType(Ty); 1243 return Context.DeclarationNames.getCXXConversionFunctionName(Ty); 1244 } 1245 1246 case Declarator::DK_Operator: 1247 assert(D.getIdentifier() == 0 && "operator names have no identifier"); 1248 return Context.DeclarationNames.getCXXOperatorName( 1249 D.getOverloadedOperator()); 1250 } 1251 1252 assert(false && "Unknown name kind"); 1253 return DeclarationName(); 1254} 1255 1256/// isNearlyMatchingMemberFunction - Determine whether the C++ member 1257/// functions Declaration and Definition are "nearly" matching. This 1258/// heuristic is used to improve diagnostics in the case where an 1259/// out-of-line member function definition doesn't match any 1260/// declaration within the class. 1261static bool isNearlyMatchingMemberFunction(ASTContext &Context, 1262 FunctionDecl *Declaration, 1263 FunctionDecl *Definition) { 1264 if (Declaration->param_size() != Definition->param_size()) 1265 return false; 1266 for (unsigned Idx = 0; Idx < Declaration->param_size(); ++Idx) { 1267 QualType DeclParamTy = Declaration->getParamDecl(Idx)->getType(); 1268 QualType DefParamTy = Definition->getParamDecl(Idx)->getType(); 1269 1270 DeclParamTy = Context.getCanonicalType(DeclParamTy.getNonReferenceType()); 1271 DefParamTy = Context.getCanonicalType(DefParamTy.getNonReferenceType()); 1272 if (DeclParamTy.getUnqualifiedType() != DefParamTy.getUnqualifiedType()) 1273 return false; 1274 } 1275 1276 return true; 1277} 1278 1279Sema::DeclTy * 1280Sema::ActOnDeclarator(Scope *S, Declarator &D, DeclTy *lastDecl, 1281 bool IsFunctionDefinition) { 1282 ScopedDecl *LastDeclarator = dyn_cast_or_null<ScopedDecl>((Decl *)lastDecl); 1283 DeclarationName Name = GetNameForDeclarator(D); 1284 1285 // All of these full declarators require an identifier. If it doesn't have 1286 // one, the ParsedFreeStandingDeclSpec action should be used. 1287 if (!Name) { 1288 if (!D.getInvalidType()) // Reject this if we think it is valid. 1289 Diag(D.getDeclSpec().getSourceRange().getBegin(), 1290 diag::err_declarator_need_ident) 1291 << D.getDeclSpec().getSourceRange() << D.getSourceRange(); 1292 return 0; 1293 } 1294 1295 // The scope passed in may not be a decl scope. Zip up the scope tree until 1296 // we find one that is. 1297 while ((S->getFlags() & Scope::DeclScope) == 0 || 1298 (S->getFlags() & Scope::TemplateParamScope) != 0) 1299 S = S->getParent(); 1300 1301 DeclContext *DC; 1302 Decl *PrevDecl; 1303 ScopedDecl *New; 1304 bool InvalidDecl = false; 1305 1306 // See if this is a redefinition of a variable in the same scope. 1307 if (!D.getCXXScopeSpec().isSet()) { 1308 DC = CurContext; 1309 PrevDecl = LookupDecl(Name, Decl::IDNS_Ordinary, S); 1310 } else { // Something like "int foo::x;" 1311 DC = static_cast<DeclContext*>(D.getCXXScopeSpec().getScopeRep()); 1312 PrevDecl = LookupDecl(Name, Decl::IDNS_Ordinary, S, DC); 1313 1314 // C++ 7.3.1.2p2: 1315 // Members (including explicit specializations of templates) of a named 1316 // namespace can also be defined outside that namespace by explicit 1317 // qualification of the name being defined, provided that the entity being 1318 // defined was already declared in the namespace and the definition appears 1319 // after the point of declaration in a namespace that encloses the 1320 // declarations namespace. 1321 // 1322 // Note that we only check the context at this point. We don't yet 1323 // have enough information to make sure that PrevDecl is actually 1324 // the declaration we want to match. For example, given: 1325 // 1326 // class X { 1327 // void f(); 1328 // void f(float); 1329 // }; 1330 // 1331 // void X::f(int) { } // ill-formed 1332 // 1333 // In this case, PrevDecl will point to the overload set 1334 // containing the two f's declared in X, but neither of them 1335 // matches. 1336 if (!CurContext->Encloses(DC)) { 1337 // The qualifying scope doesn't enclose the original declaration. 1338 // Emit diagnostic based on current scope. 1339 SourceLocation L = D.getIdentifierLoc(); 1340 SourceRange R = D.getCXXScopeSpec().getRange(); 1341 if (isa<FunctionDecl>(CurContext)) { 1342 Diag(L, diag::err_invalid_declarator_in_function) << Name << R; 1343 } else { 1344 Diag(L, diag::err_invalid_declarator_scope) 1345 << Name << cast<NamedDecl>(DC)->getDeclName() << R; 1346 } 1347 InvalidDecl = true; 1348 } 1349 } 1350 1351 if (PrevDecl && PrevDecl->isTemplateParameter()) { 1352 // Maybe we will complain about the shadowed template parameter. 1353 InvalidDecl = InvalidDecl 1354 || DiagnoseTemplateParameterShadow(D.getIdentifierLoc(), PrevDecl); 1355 // Just pretend that we didn't see the previous declaration. 1356 PrevDecl = 0; 1357 } 1358 1359 // In C++, the previous declaration we find might be a tag type 1360 // (class or enum). In this case, the new declaration will hide the 1361 // tag type. 1362 if (PrevDecl && PrevDecl->getIdentifierNamespace() == Decl::IDNS_Tag) 1363 PrevDecl = 0; 1364 1365 QualType R = GetTypeForDeclarator(D, S); 1366 assert(!R.isNull() && "GetTypeForDeclarator() returned null type"); 1367 1368 if (D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_typedef) { 1369 // Typedef declarators cannot be qualified (C++ [dcl.meaning]p1). 1370 if (D.getCXXScopeSpec().isSet()) { 1371 Diag(D.getIdentifierLoc(), diag::err_qualified_typedef_declarator) 1372 << D.getCXXScopeSpec().getRange(); 1373 InvalidDecl = true; 1374 // Pretend we didn't see the scope specifier. 1375 DC = 0; 1376 } 1377 1378 // Check that there are no default arguments (C++ only). 1379 if (getLangOptions().CPlusPlus) 1380 CheckExtraCXXDefaultArguments(D); 1381 1382 TypedefDecl *NewTD = ParseTypedefDecl(S, D, R, LastDeclarator); 1383 if (!NewTD) return 0; 1384 1385 // Handle attributes prior to checking for duplicates in MergeVarDecl 1386 ProcessDeclAttributes(NewTD, D); 1387 // Merge the decl with the existing one if appropriate. If the decl is 1388 // in an outer scope, it isn't the same thing. 1389 if (PrevDecl && isDeclInScope(PrevDecl, DC, S)) { 1390 NewTD = MergeTypeDefDecl(NewTD, PrevDecl); 1391 if (NewTD == 0) return 0; 1392 } 1393 New = NewTD; 1394 if (S->getFnParent() == 0) { 1395 // C99 6.7.7p2: If a typedef name specifies a variably modified type 1396 // then it shall have block scope. 1397 if (NewTD->getUnderlyingType()->isVariablyModifiedType()) { 1398 if (NewTD->getUnderlyingType()->isVariableArrayType()) 1399 Diag(D.getIdentifierLoc(), diag::err_vla_decl_in_file_scope); 1400 else 1401 Diag(D.getIdentifierLoc(), diag::err_vm_decl_in_file_scope); 1402 1403 InvalidDecl = true; 1404 } 1405 } 1406 } else if (R.getTypePtr()->isFunctionType()) { 1407 FunctionDecl::StorageClass SC = FunctionDecl::None; 1408 switch (D.getDeclSpec().getStorageClassSpec()) { 1409 default: assert(0 && "Unknown storage class!"); 1410 case DeclSpec::SCS_auto: 1411 case DeclSpec::SCS_register: 1412 case DeclSpec::SCS_mutable: 1413 Diag(D.getIdentifierLoc(), diag::err_typecheck_sclass_func); 1414 InvalidDecl = true; 1415 break; 1416 case DeclSpec::SCS_unspecified: SC = FunctionDecl::None; break; 1417 case DeclSpec::SCS_extern: SC = FunctionDecl::Extern; break; 1418 case DeclSpec::SCS_static: SC = FunctionDecl::Static; break; 1419 case DeclSpec::SCS_private_extern: SC = FunctionDecl::PrivateExtern;break; 1420 } 1421 1422 bool isInline = D.getDeclSpec().isInlineSpecified(); 1423 // bool isVirtual = D.getDeclSpec().isVirtualSpecified(); 1424 bool isExplicit = D.getDeclSpec().isExplicitSpecified(); 1425 1426 FunctionDecl *NewFD; 1427 if (D.getKind() == Declarator::DK_Constructor) { 1428 // This is a C++ constructor declaration. 1429 assert(DC->isRecord() && 1430 "Constructors can only be declared in a member context"); 1431 1432 InvalidDecl = InvalidDecl || CheckConstructorDeclarator(D, R, SC); 1433 1434 // Create the new declaration 1435 NewFD = CXXConstructorDecl::Create(Context, 1436 cast<CXXRecordDecl>(DC), 1437 D.getIdentifierLoc(), Name, R, 1438 isExplicit, isInline, 1439 /*isImplicitlyDeclared=*/false); 1440 1441 if (InvalidDecl) 1442 NewFD->setInvalidDecl(); 1443 } else if (D.getKind() == Declarator::DK_Destructor) { 1444 // This is a C++ destructor declaration. 1445 if (DC->isRecord()) { 1446 InvalidDecl = InvalidDecl || CheckDestructorDeclarator(D, R, SC); 1447 1448 NewFD = CXXDestructorDecl::Create(Context, 1449 cast<CXXRecordDecl>(DC), 1450 D.getIdentifierLoc(), Name, R, 1451 isInline, 1452 /*isImplicitlyDeclared=*/false); 1453 1454 if (InvalidDecl) 1455 NewFD->setInvalidDecl(); 1456 } else { 1457 Diag(D.getIdentifierLoc(), diag::err_destructor_not_member); 1458 1459 // Create a FunctionDecl to satisfy the function definition parsing 1460 // code path. 1461 NewFD = FunctionDecl::Create(Context, DC, D.getIdentifierLoc(), 1462 Name, R, SC, isInline, LastDeclarator, 1463 // FIXME: Move to DeclGroup... 1464 D.getDeclSpec().getSourceRange().getBegin()); 1465 InvalidDecl = true; 1466 NewFD->setInvalidDecl(); 1467 } 1468 } else if (D.getKind() == Declarator::DK_Conversion) { 1469 if (!DC->isRecord()) { 1470 Diag(D.getIdentifierLoc(), 1471 diag::err_conv_function_not_member); 1472 return 0; 1473 } else { 1474 InvalidDecl = InvalidDecl || CheckConversionDeclarator(D, R, SC); 1475 1476 NewFD = CXXConversionDecl::Create(Context, cast<CXXRecordDecl>(DC), 1477 D.getIdentifierLoc(), Name, R, 1478 isInline, isExplicit); 1479 1480 if (InvalidDecl) 1481 NewFD->setInvalidDecl(); 1482 } 1483 } else if (DC->isRecord()) { 1484 // This is a C++ method declaration. 1485 NewFD = CXXMethodDecl::Create(Context, cast<CXXRecordDecl>(DC), 1486 D.getIdentifierLoc(), Name, R, 1487 (SC == FunctionDecl::Static), isInline, 1488 LastDeclarator); 1489 } else { 1490 NewFD = FunctionDecl::Create(Context, DC, 1491 D.getIdentifierLoc(), 1492 Name, R, SC, isInline, LastDeclarator, 1493 // FIXME: Move to DeclGroup... 1494 D.getDeclSpec().getSourceRange().getBegin()); 1495 } 1496 1497 // Set the lexical context. If the declarator has a C++ 1498 // scope specifier, the lexical context will be different 1499 // from the semantic context. 1500 NewFD->setLexicalDeclContext(CurContext); 1501 1502 // Handle GNU asm-label extension (encoded as an attribute). 1503 if (Expr *E = (Expr*) D.getAsmLabel()) { 1504 // The parser guarantees this is a string. 1505 StringLiteral *SE = cast<StringLiteral>(E); 1506 NewFD->addAttr(new AsmLabelAttr(std::string(SE->getStrData(), 1507 SE->getByteLength()))); 1508 } 1509 1510 // Copy the parameter declarations from the declarator D to 1511 // the function declaration NewFD, if they are available. 1512 if (D.getNumTypeObjects() > 0) { 1513 DeclaratorChunk::FunctionTypeInfo &FTI = D.getTypeObject(0).Fun; 1514 1515 // Create Decl objects for each parameter, adding them to the 1516 // FunctionDecl. 1517 llvm::SmallVector<ParmVarDecl*, 16> Params; 1518 1519 // Check for C99 6.7.5.3p10 - foo(void) is a non-varargs 1520 // function that takes no arguments, not a function that takes a 1521 // single void argument. 1522 // We let through "const void" here because Sema::GetTypeForDeclarator 1523 // already checks for that case. 1524 if (FTI.NumArgs == 1 && !FTI.isVariadic && FTI.ArgInfo[0].Ident == 0 && 1525 FTI.ArgInfo[0].Param && 1526 ((ParmVarDecl*)FTI.ArgInfo[0].Param)->getType()->isVoidType()) { 1527 // empty arg list, don't push any params. 1528 ParmVarDecl *Param = (ParmVarDecl*)FTI.ArgInfo[0].Param; 1529 1530 // In C++, the empty parameter-type-list must be spelled "void"; a 1531 // typedef of void is not permitted. 1532 if (getLangOptions().CPlusPlus && 1533 Param->getType().getUnqualifiedType() != Context.VoidTy) { 1534 Diag(Param->getLocation(), diag::ext_param_typedef_of_void); 1535 } 1536 } else if (FTI.NumArgs > 0 && FTI.ArgInfo[0].Param != 0) { 1537 for (unsigned i = 0, e = FTI.NumArgs; i != e; ++i) 1538 Params.push_back((ParmVarDecl *)FTI.ArgInfo[i].Param); 1539 } 1540 1541 NewFD->setParams(&Params[0], Params.size()); 1542 } else if (R->getAsTypedefType()) { 1543 // When we're declaring a function with a typedef, as in the 1544 // following example, we'll need to synthesize (unnamed) 1545 // parameters for use in the declaration. 1546 // 1547 // @code 1548 // typedef void fn(int); 1549 // fn f; 1550 // @endcode 1551 const FunctionTypeProto *FT = R->getAsFunctionTypeProto(); 1552 if (!FT) { 1553 // This is a typedef of a function with no prototype, so we 1554 // don't need to do anything. 1555 } else if ((FT->getNumArgs() == 0) || 1556 (FT->getNumArgs() == 1 && !FT->isVariadic() && 1557 FT->getArgType(0)->isVoidType())) { 1558 // This is a zero-argument function. We don't need to do anything. 1559 } else { 1560 // Synthesize a parameter for each argument type. 1561 llvm::SmallVector<ParmVarDecl*, 16> Params; 1562 for (FunctionTypeProto::arg_type_iterator ArgType = FT->arg_type_begin(); 1563 ArgType != FT->arg_type_end(); ++ArgType) { 1564 Params.push_back(ParmVarDecl::Create(Context, DC, 1565 SourceLocation(), 0, 1566 *ArgType, VarDecl::None, 1567 0, 0)); 1568 } 1569 1570 NewFD->setParams(&Params[0], Params.size()); 1571 } 1572 } 1573 1574 if (CXXConstructorDecl *Constructor = dyn_cast<CXXConstructorDecl>(NewFD)) 1575 InvalidDecl = InvalidDecl || CheckConstructor(Constructor); 1576 else if (isa<CXXDestructorDecl>(NewFD)) { 1577 CXXRecordDecl *Record = cast<CXXRecordDecl>(NewFD->getParent()); 1578 Record->setUserDeclaredDestructor(true); 1579 // C++ [class]p4: A POD-struct is an aggregate class that has [...] no 1580 // user-defined destructor. 1581 Record->setPOD(false); 1582 } else if (CXXConversionDecl *Conversion = 1583 dyn_cast<CXXConversionDecl>(NewFD)) 1584 ActOnConversionDeclarator(Conversion); 1585 1586 // Extra checking for C++ overloaded operators (C++ [over.oper]). 1587 if (NewFD->isOverloadedOperator() && 1588 CheckOverloadedOperatorDeclaration(NewFD)) 1589 NewFD->setInvalidDecl(); 1590 1591 // Merge the decl with the existing one if appropriate. Since C functions 1592 // are in a flat namespace, make sure we consider decls in outer scopes. 1593 if (PrevDecl && 1594 (!getLangOptions().CPlusPlus||isDeclInScope(PrevDecl, DC, S))) { 1595 bool Redeclaration = false; 1596 1597 // If C++, determine whether NewFD is an overload of PrevDecl or 1598 // a declaration that requires merging. If it's an overload, 1599 // there's no more work to do here; we'll just add the new 1600 // function to the scope. 1601 OverloadedFunctionDecl::function_iterator MatchedDecl; 1602 if (!getLangOptions().CPlusPlus || 1603 !IsOverload(NewFD, PrevDecl, MatchedDecl)) { 1604 Decl *OldDecl = PrevDecl; 1605 1606 // If PrevDecl was an overloaded function, extract the 1607 // FunctionDecl that matched. 1608 if (isa<OverloadedFunctionDecl>(PrevDecl)) 1609 OldDecl = *MatchedDecl; 1610 1611 // NewFD and PrevDecl represent declarations that need to be 1612 // merged. 1613 NewFD = MergeFunctionDecl(NewFD, OldDecl, Redeclaration); 1614 1615 if (NewFD == 0) return 0; 1616 if (Redeclaration) { 1617 NewFD->setPreviousDeclaration(cast<FunctionDecl>(OldDecl)); 1618 1619 // An out-of-line member function declaration must also be a 1620 // definition (C++ [dcl.meaning]p1). 1621 if (!IsFunctionDefinition && D.getCXXScopeSpec().isSet() && 1622 !InvalidDecl) { 1623 Diag(NewFD->getLocation(), diag::err_out_of_line_declaration) 1624 << D.getCXXScopeSpec().getRange(); 1625 NewFD->setInvalidDecl(); 1626 } 1627 } 1628 } 1629 1630 if (!Redeclaration && D.getCXXScopeSpec().isSet()) { 1631 // The user tried to provide an out-of-line definition for a 1632 // member function, but there was no such member function 1633 // declared (C++ [class.mfct]p2). For example: 1634 // 1635 // class X { 1636 // void f() const; 1637 // }; 1638 // 1639 // void X::f() { } // ill-formed 1640 // 1641 // Complain about this problem, and attempt to suggest close 1642 // matches (e.g., those that differ only in cv-qualifiers and 1643 // whether the parameter types are references). 1644 Diag(D.getIdentifierLoc(), diag::err_member_def_does_not_match) 1645 << cast<CXXRecordDecl>(DC)->getDeclName() 1646 << D.getCXXScopeSpec().getRange(); 1647 InvalidDecl = true; 1648 1649 PrevDecl = LookupDecl(Name, Decl::IDNS_Ordinary, S, DC); 1650 if (!PrevDecl) { 1651 // Nothing to suggest. 1652 } else if (OverloadedFunctionDecl *Ovl 1653 = dyn_cast<OverloadedFunctionDecl>(PrevDecl)) { 1654 for (OverloadedFunctionDecl::function_iterator 1655 Func = Ovl->function_begin(), 1656 FuncEnd = Ovl->function_end(); 1657 Func != FuncEnd; ++Func) { 1658 if (isNearlyMatchingMemberFunction(Context, *Func, NewFD)) 1659 Diag((*Func)->getLocation(), diag::note_member_def_close_match); 1660 1661 } 1662 } else if (CXXMethodDecl *Method = dyn_cast<CXXMethodDecl>(PrevDecl)) { 1663 // Suggest this no matter how mismatched it is; it's the only 1664 // thing we have. 1665 unsigned diag; 1666 if (isNearlyMatchingMemberFunction(Context, Method, NewFD)) 1667 diag = diag::note_member_def_close_match; 1668 else if (Method->getBody()) 1669 diag = diag::note_previous_definition; 1670 else 1671 diag = diag::note_previous_declaration; 1672 Diag(Method->getLocation(), diag); 1673 } 1674 1675 PrevDecl = 0; 1676 } 1677 } 1678 // Handle attributes. We need to have merged decls when handling attributes 1679 // (for example to check for conflicts, etc). 1680 ProcessDeclAttributes(NewFD, D); 1681 New = NewFD; 1682 1683 if (getLangOptions().CPlusPlus) { 1684 // In C++, check default arguments now that we have merged decls. 1685 CheckCXXDefaultArguments(NewFD); 1686 1687 // An out-of-line member function declaration must also be a 1688 // definition (C++ [dcl.meaning]p1). 1689 if (!IsFunctionDefinition && D.getCXXScopeSpec().isSet() && !InvalidDecl) { 1690 Diag(NewFD->getLocation(), diag::err_out_of_line_declaration) 1691 << D.getCXXScopeSpec().getRange(); 1692 InvalidDecl = true; 1693 } 1694 } 1695 } else { 1696 // Check that there are no default arguments (C++ only). 1697 if (getLangOptions().CPlusPlus) 1698 CheckExtraCXXDefaultArguments(D); 1699 1700 if (R.getTypePtr()->isObjCInterfaceType()) { 1701 Diag(D.getIdentifierLoc(), diag::err_statically_allocated_object) 1702 << D.getIdentifier(); 1703 InvalidDecl = true; 1704 } 1705 1706 VarDecl *NewVD; 1707 VarDecl::StorageClass SC; 1708 switch (D.getDeclSpec().getStorageClassSpec()) { 1709 default: assert(0 && "Unknown storage class!"); 1710 case DeclSpec::SCS_unspecified: SC = VarDecl::None; break; 1711 case DeclSpec::SCS_extern: SC = VarDecl::Extern; break; 1712 case DeclSpec::SCS_static: SC = VarDecl::Static; break; 1713 case DeclSpec::SCS_auto: SC = VarDecl::Auto; break; 1714 case DeclSpec::SCS_register: SC = VarDecl::Register; break; 1715 case DeclSpec::SCS_private_extern: SC = VarDecl::PrivateExtern; break; 1716 case DeclSpec::SCS_mutable: 1717 // mutable can only appear on non-static class members, so it's always 1718 // an error here 1719 Diag(D.getIdentifierLoc(), diag::err_mutable_nonmember); 1720 InvalidDecl = true; 1721 SC = VarDecl::None; 1722 break; 1723 } 1724 1725 IdentifierInfo *II = Name.getAsIdentifierInfo(); 1726 if (!II) { 1727 Diag(D.getIdentifierLoc(), diag::err_bad_variable_name) 1728 << Name.getAsString(); 1729 return 0; 1730 } 1731 1732 if (DC->isRecord()) { 1733 // This is a static data member for a C++ class. 1734 NewVD = CXXClassVarDecl::Create(Context, cast<CXXRecordDecl>(DC), 1735 D.getIdentifierLoc(), II, 1736 R, LastDeclarator); 1737 } else { 1738 bool ThreadSpecified = D.getDeclSpec().isThreadSpecified(); 1739 if (S->getFnParent() == 0) { 1740 // C99 6.9p2: The storage-class specifiers auto and register shall not 1741 // appear in the declaration specifiers in an external declaration. 1742 if (SC == VarDecl::Auto || SC == VarDecl::Register) { 1743 Diag(D.getIdentifierLoc(), diag::err_typecheck_sclass_fscope); 1744 InvalidDecl = true; 1745 } 1746 } 1747 NewVD = VarDecl::Create(Context, DC, D.getIdentifierLoc(), 1748 II, R, SC, LastDeclarator, 1749 // FIXME: Move to DeclGroup... 1750 D.getDeclSpec().getSourceRange().getBegin()); 1751 NewVD->setThreadSpecified(ThreadSpecified); 1752 } 1753 // Handle attributes prior to checking for duplicates in MergeVarDecl 1754 ProcessDeclAttributes(NewVD, D); 1755 1756 // Handle GNU asm-label extension (encoded as an attribute). 1757 if (Expr *E = (Expr*) D.getAsmLabel()) { 1758 // The parser guarantees this is a string. 1759 StringLiteral *SE = cast<StringLiteral>(E); 1760 NewVD->addAttr(new AsmLabelAttr(std::string(SE->getStrData(), 1761 SE->getByteLength()))); 1762 } 1763 1764 // Emit an error if an address space was applied to decl with local storage. 1765 // This includes arrays of objects with address space qualifiers, but not 1766 // automatic variables that point to other address spaces. 1767 // ISO/IEC TR 18037 S5.1.2 1768 if (NewVD->hasLocalStorage() && (NewVD->getType().getAddressSpace() != 0)) { 1769 Diag(D.getIdentifierLoc(), diag::err_as_qualified_auto_decl); 1770 InvalidDecl = true; 1771 } 1772 // Merge the decl with the existing one if appropriate. If the decl is 1773 // in an outer scope, it isn't the same thing. 1774 if (PrevDecl && isDeclInScope(PrevDecl, DC, S)) { 1775 if (isa<FieldDecl>(PrevDecl) && D.getCXXScopeSpec().isSet()) { 1776 // The user tried to define a non-static data member 1777 // out-of-line (C++ [dcl.meaning]p1). 1778 Diag(NewVD->getLocation(), diag::err_nonstatic_member_out_of_line) 1779 << D.getCXXScopeSpec().getRange(); 1780 NewVD->Destroy(Context); 1781 return 0; 1782 } 1783 1784 NewVD = MergeVarDecl(NewVD, PrevDecl); 1785 if (NewVD == 0) return 0; 1786 1787 if (D.getCXXScopeSpec().isSet()) { 1788 // No previous declaration in the qualifying scope. 1789 Diag(D.getIdentifierLoc(), diag::err_typecheck_no_member) 1790 << Name << D.getCXXScopeSpec().getRange(); 1791 InvalidDecl = true; 1792 } 1793 } 1794 New = NewVD; 1795 } 1796 1797 // Set the lexical context. If the declarator has a C++ scope specifier, the 1798 // lexical context will be different from the semantic context. 1799 New->setLexicalDeclContext(CurContext); 1800 1801 // If this has an identifier, add it to the scope stack. 1802 if (Name) 1803 PushOnScopeChains(New, S); 1804 // If any semantic error occurred, mark the decl as invalid. 1805 if (D.getInvalidType() || InvalidDecl) 1806 New->setInvalidDecl(); 1807 1808 return New; 1809} 1810 1811void Sema::InitializerElementNotConstant(const Expr *Init) { 1812 Diag(Init->getExprLoc(), diag::err_init_element_not_constant) 1813 << Init->getSourceRange(); 1814} 1815 1816bool Sema::CheckAddressConstantExpressionLValue(const Expr* Init) { 1817 switch (Init->getStmtClass()) { 1818 default: 1819 InitializerElementNotConstant(Init); 1820 return true; 1821 case Expr::ParenExprClass: { 1822 const ParenExpr* PE = cast<ParenExpr>(Init); 1823 return CheckAddressConstantExpressionLValue(PE->getSubExpr()); 1824 } 1825 case Expr::CompoundLiteralExprClass: 1826 return cast<CompoundLiteralExpr>(Init)->isFileScope(); 1827 case Expr::DeclRefExprClass: 1828 case Expr::QualifiedDeclRefExprClass: { 1829 const Decl *D = cast<DeclRefExpr>(Init)->getDecl(); 1830 if (const VarDecl *VD = dyn_cast<VarDecl>(D)) { 1831 if (VD->hasGlobalStorage()) 1832 return false; 1833 InitializerElementNotConstant(Init); 1834 return true; 1835 } 1836 if (isa<FunctionDecl>(D)) 1837 return false; 1838 InitializerElementNotConstant(Init); 1839 return true; 1840 } 1841 case Expr::MemberExprClass: { 1842 const MemberExpr *M = cast<MemberExpr>(Init); 1843 if (M->isArrow()) 1844 return CheckAddressConstantExpression(M->getBase()); 1845 return CheckAddressConstantExpressionLValue(M->getBase()); 1846 } 1847 case Expr::ArraySubscriptExprClass: { 1848 // FIXME: Should we pedwarn for "x[0+0]" (where x is a pointer)? 1849 const ArraySubscriptExpr *ASE = cast<ArraySubscriptExpr>(Init); 1850 return CheckAddressConstantExpression(ASE->getBase()) || 1851 CheckArithmeticConstantExpression(ASE->getIdx()); 1852 } 1853 case Expr::StringLiteralClass: 1854 case Expr::PredefinedExprClass: 1855 return false; 1856 case Expr::UnaryOperatorClass: { 1857 const UnaryOperator *Exp = cast<UnaryOperator>(Init); 1858 1859 // C99 6.6p9 1860 if (Exp->getOpcode() == UnaryOperator::Deref) 1861 return CheckAddressConstantExpression(Exp->getSubExpr()); 1862 1863 InitializerElementNotConstant(Init); 1864 return true; 1865 } 1866 } 1867} 1868 1869bool Sema::CheckAddressConstantExpression(const Expr* Init) { 1870 switch (Init->getStmtClass()) { 1871 default: 1872 InitializerElementNotConstant(Init); 1873 return true; 1874 case Expr::ParenExprClass: 1875 return CheckAddressConstantExpression(cast<ParenExpr>(Init)->getSubExpr()); 1876 case Expr::StringLiteralClass: 1877 case Expr::ObjCStringLiteralClass: 1878 return false; 1879 case Expr::CallExprClass: 1880 case Expr::CXXOperatorCallExprClass: 1881 // __builtin___CFStringMakeConstantString is a valid constant l-value. 1882 if (cast<CallExpr>(Init)->isBuiltinCall() == 1883 Builtin::BI__builtin___CFStringMakeConstantString) 1884 return false; 1885 1886 InitializerElementNotConstant(Init); 1887 return true; 1888 1889 case Expr::UnaryOperatorClass: { 1890 const UnaryOperator *Exp = cast<UnaryOperator>(Init); 1891 1892 // C99 6.6p9 1893 if (Exp->getOpcode() == UnaryOperator::AddrOf) 1894 return CheckAddressConstantExpressionLValue(Exp->getSubExpr()); 1895 1896 if (Exp->getOpcode() == UnaryOperator::Extension) 1897 return CheckAddressConstantExpression(Exp->getSubExpr()); 1898 1899 InitializerElementNotConstant(Init); 1900 return true; 1901 } 1902 case Expr::BinaryOperatorClass: { 1903 // FIXME: Should we pedwarn for expressions like "a + 1 + 2"? 1904 const BinaryOperator *Exp = cast<BinaryOperator>(Init); 1905 1906 Expr *PExp = Exp->getLHS(); 1907 Expr *IExp = Exp->getRHS(); 1908 if (IExp->getType()->isPointerType()) 1909 std::swap(PExp, IExp); 1910 1911 // FIXME: Should we pedwarn if IExp isn't an integer constant expression? 1912 return CheckAddressConstantExpression(PExp) || 1913 CheckArithmeticConstantExpression(IExp); 1914 } 1915 case Expr::ImplicitCastExprClass: 1916 case Expr::CStyleCastExprClass: { 1917 const Expr* SubExpr = cast<CastExpr>(Init)->getSubExpr(); 1918 if (Init->getStmtClass() == Expr::ImplicitCastExprClass) { 1919 // Check for implicit promotion 1920 if (SubExpr->getType()->isFunctionType() || 1921 SubExpr->getType()->isArrayType()) 1922 return CheckAddressConstantExpressionLValue(SubExpr); 1923 } 1924 1925 // Check for pointer->pointer cast 1926 if (SubExpr->getType()->isPointerType()) 1927 return CheckAddressConstantExpression(SubExpr); 1928 1929 if (SubExpr->getType()->isIntegralType()) { 1930 // Check for the special-case of a pointer->int->pointer cast; 1931 // this isn't standard, but some code requires it. See 1932 // PR2720 for an example. 1933 if (const CastExpr* SubCast = dyn_cast<CastExpr>(SubExpr)) { 1934 if (SubCast->getSubExpr()->getType()->isPointerType()) { 1935 unsigned IntWidth = Context.getIntWidth(SubCast->getType()); 1936 unsigned PointerWidth = Context.getTypeSize(Context.VoidPtrTy); 1937 if (IntWidth >= PointerWidth) { 1938 return CheckAddressConstantExpression(SubCast->getSubExpr()); 1939 } 1940 } 1941 } 1942 } 1943 if (SubExpr->getType()->isArithmeticType()) { 1944 return CheckArithmeticConstantExpression(SubExpr); 1945 } 1946 1947 InitializerElementNotConstant(Init); 1948 return true; 1949 } 1950 case Expr::ConditionalOperatorClass: { 1951 // FIXME: Should we pedwarn here? 1952 const ConditionalOperator *Exp = cast<ConditionalOperator>(Init); 1953 if (!Exp->getCond()->getType()->isArithmeticType()) { 1954 InitializerElementNotConstant(Init); 1955 return true; 1956 } 1957 if (CheckArithmeticConstantExpression(Exp->getCond())) 1958 return true; 1959 if (Exp->getLHS() && 1960 CheckAddressConstantExpression(Exp->getLHS())) 1961 return true; 1962 return CheckAddressConstantExpression(Exp->getRHS()); 1963 } 1964 case Expr::AddrLabelExprClass: 1965 return false; 1966 } 1967} 1968 1969static const Expr* FindExpressionBaseAddress(const Expr* E); 1970 1971static const Expr* FindExpressionBaseAddressLValue(const Expr* E) { 1972 switch (E->getStmtClass()) { 1973 default: 1974 return E; 1975 case Expr::ParenExprClass: { 1976 const ParenExpr* PE = cast<ParenExpr>(E); 1977 return FindExpressionBaseAddressLValue(PE->getSubExpr()); 1978 } 1979 case Expr::MemberExprClass: { 1980 const MemberExpr *M = cast<MemberExpr>(E); 1981 if (M->isArrow()) 1982 return FindExpressionBaseAddress(M->getBase()); 1983 return FindExpressionBaseAddressLValue(M->getBase()); 1984 } 1985 case Expr::ArraySubscriptExprClass: { 1986 const ArraySubscriptExpr *ASE = cast<ArraySubscriptExpr>(E); 1987 return FindExpressionBaseAddress(ASE->getBase()); 1988 } 1989 case Expr::UnaryOperatorClass: { 1990 const UnaryOperator *Exp = cast<UnaryOperator>(E); 1991 1992 if (Exp->getOpcode() == UnaryOperator::Deref) 1993 return FindExpressionBaseAddress(Exp->getSubExpr()); 1994 1995 return E; 1996 } 1997 } 1998} 1999 2000static const Expr* FindExpressionBaseAddress(const Expr* E) { 2001 switch (E->getStmtClass()) { 2002 default: 2003 return E; 2004 case Expr::ParenExprClass: { 2005 const ParenExpr* PE = cast<ParenExpr>(E); 2006 return FindExpressionBaseAddress(PE->getSubExpr()); 2007 } 2008 case Expr::UnaryOperatorClass: { 2009 const UnaryOperator *Exp = cast<UnaryOperator>(E); 2010 2011 // C99 6.6p9 2012 if (Exp->getOpcode() == UnaryOperator::AddrOf) 2013 return FindExpressionBaseAddressLValue(Exp->getSubExpr()); 2014 2015 if (Exp->getOpcode() == UnaryOperator::Extension) 2016 return FindExpressionBaseAddress(Exp->getSubExpr()); 2017 2018 return E; 2019 } 2020 case Expr::BinaryOperatorClass: { 2021 const BinaryOperator *Exp = cast<BinaryOperator>(E); 2022 2023 Expr *PExp = Exp->getLHS(); 2024 Expr *IExp = Exp->getRHS(); 2025 if (IExp->getType()->isPointerType()) 2026 std::swap(PExp, IExp); 2027 2028 return FindExpressionBaseAddress(PExp); 2029 } 2030 case Expr::ImplicitCastExprClass: { 2031 const Expr* SubExpr = cast<ImplicitCastExpr>(E)->getSubExpr(); 2032 2033 // Check for implicit promotion 2034 if (SubExpr->getType()->isFunctionType() || 2035 SubExpr->getType()->isArrayType()) 2036 return FindExpressionBaseAddressLValue(SubExpr); 2037 2038 // Check for pointer->pointer cast 2039 if (SubExpr->getType()->isPointerType()) 2040 return FindExpressionBaseAddress(SubExpr); 2041 2042 // We assume that we have an arithmetic expression here; 2043 // if we don't, we'll figure it out later 2044 return 0; 2045 } 2046 case Expr::CStyleCastExprClass: { 2047 const Expr* SubExpr = cast<CastExpr>(E)->getSubExpr(); 2048 2049 // Check for pointer->pointer cast 2050 if (SubExpr->getType()->isPointerType()) 2051 return FindExpressionBaseAddress(SubExpr); 2052 2053 // We assume that we have an arithmetic expression here; 2054 // if we don't, we'll figure it out later 2055 return 0; 2056 } 2057 } 2058} 2059 2060bool Sema::CheckArithmeticConstantExpression(const Expr* Init) { 2061 switch (Init->getStmtClass()) { 2062 default: 2063 InitializerElementNotConstant(Init); 2064 return true; 2065 case Expr::ParenExprClass: { 2066 const ParenExpr* PE = cast<ParenExpr>(Init); 2067 return CheckArithmeticConstantExpression(PE->getSubExpr()); 2068 } 2069 case Expr::FloatingLiteralClass: 2070 case Expr::IntegerLiteralClass: 2071 case Expr::CharacterLiteralClass: 2072 case Expr::ImaginaryLiteralClass: 2073 case Expr::TypesCompatibleExprClass: 2074 case Expr::CXXBoolLiteralExprClass: 2075 return false; 2076 case Expr::CallExprClass: 2077 case Expr::CXXOperatorCallExprClass: { 2078 const CallExpr *CE = cast<CallExpr>(Init); 2079 2080 // Allow any constant foldable calls to builtins. 2081 if (CE->isBuiltinCall() && CE->isEvaluatable(Context)) 2082 return false; 2083 2084 InitializerElementNotConstant(Init); 2085 return true; 2086 } 2087 case Expr::DeclRefExprClass: 2088 case Expr::QualifiedDeclRefExprClass: { 2089 const Decl *D = cast<DeclRefExpr>(Init)->getDecl(); 2090 if (isa<EnumConstantDecl>(D)) 2091 return false; 2092 InitializerElementNotConstant(Init); 2093 return true; 2094 } 2095 case Expr::CompoundLiteralExprClass: 2096 // Allow "(vector type){2,4}"; normal C constraints don't allow this, 2097 // but vectors are allowed to be magic. 2098 if (Init->getType()->isVectorType()) 2099 return false; 2100 InitializerElementNotConstant(Init); 2101 return true; 2102 case Expr::UnaryOperatorClass: { 2103 const UnaryOperator *Exp = cast<UnaryOperator>(Init); 2104 2105 switch (Exp->getOpcode()) { 2106 // Address, indirect, pre/post inc/dec, etc are not valid constant exprs. 2107 // See C99 6.6p3. 2108 default: 2109 InitializerElementNotConstant(Init); 2110 return true; 2111 case UnaryOperator::OffsetOf: 2112 if (Exp->getSubExpr()->getType()->isConstantSizeType()) 2113 return false; 2114 InitializerElementNotConstant(Init); 2115 return true; 2116 case UnaryOperator::Extension: 2117 case UnaryOperator::LNot: 2118 case UnaryOperator::Plus: 2119 case UnaryOperator::Minus: 2120 case UnaryOperator::Not: 2121 return CheckArithmeticConstantExpression(Exp->getSubExpr()); 2122 } 2123 } 2124 case Expr::SizeOfAlignOfExprClass: { 2125 const SizeOfAlignOfExpr *Exp = cast<SizeOfAlignOfExpr>(Init); 2126 // Special check for void types, which are allowed as an extension 2127 if (Exp->getTypeOfArgument()->isVoidType()) 2128 return false; 2129 // alignof always evaluates to a constant. 2130 // FIXME: is sizeof(int[3.0]) a constant expression? 2131 if (Exp->isSizeOf() && !Exp->getTypeOfArgument()->isConstantSizeType()) { 2132 InitializerElementNotConstant(Init); 2133 return true; 2134 } 2135 return false; 2136 } 2137 case Expr::BinaryOperatorClass: { 2138 const BinaryOperator *Exp = cast<BinaryOperator>(Init); 2139 2140 if (Exp->getLHS()->getType()->isArithmeticType() && 2141 Exp->getRHS()->getType()->isArithmeticType()) { 2142 return CheckArithmeticConstantExpression(Exp->getLHS()) || 2143 CheckArithmeticConstantExpression(Exp->getRHS()); 2144 } 2145 2146 if (Exp->getLHS()->getType()->isPointerType() && 2147 Exp->getRHS()->getType()->isPointerType()) { 2148 const Expr* LHSBase = FindExpressionBaseAddress(Exp->getLHS()); 2149 const Expr* RHSBase = FindExpressionBaseAddress(Exp->getRHS()); 2150 2151 // Only allow a null (constant integer) base; we could 2152 // allow some additional cases if necessary, but this 2153 // is sufficient to cover offsetof-like constructs. 2154 if (!LHSBase && !RHSBase) { 2155 return CheckAddressConstantExpression(Exp->getLHS()) || 2156 CheckAddressConstantExpression(Exp->getRHS()); 2157 } 2158 } 2159 2160 InitializerElementNotConstant(Init); 2161 return true; 2162 } 2163 case Expr::ImplicitCastExprClass: 2164 case Expr::CStyleCastExprClass: { 2165 const Expr *SubExpr = cast<CastExpr>(Init)->getSubExpr(); 2166 if (SubExpr->getType()->isArithmeticType()) 2167 return CheckArithmeticConstantExpression(SubExpr); 2168 2169 if (SubExpr->getType()->isPointerType()) { 2170 const Expr* Base = FindExpressionBaseAddress(SubExpr); 2171 // If the pointer has a null base, this is an offsetof-like construct 2172 if (!Base) 2173 return CheckAddressConstantExpression(SubExpr); 2174 } 2175 2176 InitializerElementNotConstant(Init); 2177 return true; 2178 } 2179 case Expr::ConditionalOperatorClass: { 2180 const ConditionalOperator *Exp = cast<ConditionalOperator>(Init); 2181 2182 // If GNU extensions are disabled, we require all operands to be arithmetic 2183 // constant expressions. 2184 if (getLangOptions().NoExtensions) { 2185 return CheckArithmeticConstantExpression(Exp->getCond()) || 2186 (Exp->getLHS() && CheckArithmeticConstantExpression(Exp->getLHS())) || 2187 CheckArithmeticConstantExpression(Exp->getRHS()); 2188 } 2189 2190 // Otherwise, we have to emulate some of the behavior of fold here. 2191 // Basically GCC treats things like "4 ? 1 : somefunc()" as a constant 2192 // because it can constant fold things away. To retain compatibility with 2193 // GCC code, we see if we can fold the condition to a constant (which we 2194 // should always be able to do in theory). If so, we only require the 2195 // specified arm of the conditional to be a constant. This is a horrible 2196 // hack, but is require by real world code that uses __builtin_constant_p. 2197 Expr::EvalResult EvalResult; 2198 if (!Exp->getCond()->Evaluate(EvalResult, Context) || 2199 EvalResult.HasSideEffects) { 2200 // If Evaluate couldn't fold it, CheckArithmeticConstantExpression 2201 // won't be able to either. Use it to emit the diagnostic though. 2202 bool Res = CheckArithmeticConstantExpression(Exp->getCond()); 2203 assert(Res && "Evaluate couldn't evaluate this constant?"); 2204 return Res; 2205 } 2206 2207 // Verify that the side following the condition is also a constant. 2208 const Expr *TrueSide = Exp->getLHS(), *FalseSide = Exp->getRHS(); 2209 if (EvalResult.Val.getInt() == 0) 2210 std::swap(TrueSide, FalseSide); 2211 2212 if (TrueSide && CheckArithmeticConstantExpression(TrueSide)) 2213 return true; 2214 2215 // Okay, the evaluated side evaluates to a constant, so we accept this. 2216 // Check to see if the other side is obviously not a constant. If so, 2217 // emit a warning that this is a GNU extension. 2218 if (FalseSide && !FalseSide->isEvaluatable(Context)) 2219 Diag(Init->getExprLoc(), 2220 diag::ext_typecheck_expression_not_constant_but_accepted) 2221 << FalseSide->getSourceRange(); 2222 return false; 2223 } 2224 } 2225} 2226 2227bool Sema::CheckForConstantInitializer(Expr *Init, QualType DclT) { 2228 Expr::EvalResult Result; 2229 2230 Init = Init->IgnoreParens(); 2231 2232 if (Init->Evaluate(Result, Context) && !Result.HasSideEffects) 2233 return false; 2234 2235 // Look through CXXDefaultArgExprs; they have no meaning in this context. 2236 if (CXXDefaultArgExpr* DAE = dyn_cast<CXXDefaultArgExpr>(Init)) 2237 return CheckForConstantInitializer(DAE->getExpr(), DclT); 2238 2239 if (CompoundLiteralExpr *e = dyn_cast<CompoundLiteralExpr>(Init)) 2240 return CheckForConstantInitializer(e->getInitializer(), DclT); 2241 2242 if (InitListExpr *Exp = dyn_cast<InitListExpr>(Init)) { 2243 unsigned numInits = Exp->getNumInits(); 2244 for (unsigned i = 0; i < numInits; i++) { 2245 // FIXME: Need to get the type of the declaration for C++, 2246 // because it could be a reference? 2247 if (CheckForConstantInitializer(Exp->getInit(i), 2248 Exp->getInit(i)->getType())) 2249 return true; 2250 } 2251 return false; 2252 } 2253 2254 // FIXME: We can probably remove some of this code below, now that 2255 // Expr::Evaluate is doing the heavy lifting for scalars. 2256 2257 if (Init->isNullPointerConstant(Context)) 2258 return false; 2259 if (Init->getType()->isArithmeticType()) { 2260 QualType InitTy = Context.getCanonicalType(Init->getType()) 2261 .getUnqualifiedType(); 2262 if (InitTy == Context.BoolTy) { 2263 // Special handling for pointers implicitly cast to bool; 2264 // (e.g. "_Bool rr = &rr;"). This is only legal at the top level. 2265 if (ImplicitCastExpr* ICE = dyn_cast<ImplicitCastExpr>(Init)) { 2266 Expr* SubE = ICE->getSubExpr(); 2267 if (SubE->getType()->isPointerType() || 2268 SubE->getType()->isArrayType() || 2269 SubE->getType()->isFunctionType()) { 2270 return CheckAddressConstantExpression(Init); 2271 } 2272 } 2273 } else if (InitTy->isIntegralType()) { 2274 Expr* SubE = 0; 2275 if (CastExpr* CE = dyn_cast<CastExpr>(Init)) 2276 SubE = CE->getSubExpr(); 2277 // Special check for pointer cast to int; we allow as an extension 2278 // an address constant cast to an integer if the integer 2279 // is of an appropriate width (this sort of code is apparently used 2280 // in some places). 2281 // FIXME: Add pedwarn? 2282 // FIXME: Don't allow bitfields here! Need the FieldDecl for that. 2283 if (SubE && (SubE->getType()->isPointerType() || 2284 SubE->getType()->isArrayType() || 2285 SubE->getType()->isFunctionType())) { 2286 unsigned IntWidth = Context.getTypeSize(Init->getType()); 2287 unsigned PointerWidth = Context.getTypeSize(Context.VoidPtrTy); 2288 if (IntWidth >= PointerWidth) 2289 return CheckAddressConstantExpression(Init); 2290 } 2291 } 2292 2293 return CheckArithmeticConstantExpression(Init); 2294 } 2295 2296 if (Init->getType()->isPointerType()) 2297 return CheckAddressConstantExpression(Init); 2298 2299 // An array type at the top level that isn't an init-list must 2300 // be a string literal 2301 if (Init->getType()->isArrayType()) 2302 return false; 2303 2304 if (Init->getType()->isFunctionType()) 2305 return false; 2306 2307 // Allow block exprs at top level. 2308 if (Init->getType()->isBlockPointerType()) 2309 return false; 2310 2311 InitializerElementNotConstant(Init); 2312 return true; 2313} 2314 2315void Sema::AddInitializerToDecl(DeclTy *dcl, ExprArg init) { 2316 Decl *RealDecl = static_cast<Decl *>(dcl); 2317 Expr *Init = static_cast<Expr *>(init.release()); 2318 assert(Init && "missing initializer"); 2319 2320 // If there is no declaration, there was an error parsing it. Just ignore 2321 // the initializer. 2322 if (RealDecl == 0) { 2323 delete Init; 2324 return; 2325 } 2326 2327 VarDecl *VDecl = dyn_cast<VarDecl>(RealDecl); 2328 if (!VDecl) { 2329 Diag(dyn_cast<ScopedDecl>(RealDecl)->getLocation(), 2330 diag::err_illegal_initializer); 2331 RealDecl->setInvalidDecl(); 2332 return; 2333 } 2334 // Get the decls type and save a reference for later, since 2335 // CheckInitializerTypes may change it. 2336 QualType DclT = VDecl->getType(), SavT = DclT; 2337 if (VDecl->isBlockVarDecl()) { 2338 VarDecl::StorageClass SC = VDecl->getStorageClass(); 2339 if (SC == VarDecl::Extern) { // C99 6.7.8p5 2340 Diag(VDecl->getLocation(), diag::err_block_extern_cant_init); 2341 VDecl->setInvalidDecl(); 2342 } else if (!VDecl->isInvalidDecl()) { 2343 if (CheckInitializerTypes(Init, DclT, VDecl->getLocation(), 2344 VDecl->getDeclName())) 2345 VDecl->setInvalidDecl(); 2346 2347 // C++ 3.6.2p2, allow dynamic initialization of static initializers. 2348 if (!getLangOptions().CPlusPlus) { 2349 if (SC == VarDecl::Static) // C99 6.7.8p4. 2350 CheckForConstantInitializer(Init, DclT); 2351 } 2352 } 2353 } else if (VDecl->isFileVarDecl()) { 2354 if (VDecl->getStorageClass() == VarDecl::Extern) 2355 Diag(VDecl->getLocation(), diag::warn_extern_init); 2356 if (!VDecl->isInvalidDecl()) 2357 if (CheckInitializerTypes(Init, DclT, VDecl->getLocation(), 2358 VDecl->getDeclName())) 2359 VDecl->setInvalidDecl(); 2360 2361 // C++ 3.6.2p2, allow dynamic initialization of static initializers. 2362 if (!getLangOptions().CPlusPlus) { 2363 // C99 6.7.8p4. All file scoped initializers need to be constant. 2364 CheckForConstantInitializer(Init, DclT); 2365 } 2366 } 2367 // If the type changed, it means we had an incomplete type that was 2368 // completed by the initializer. For example: 2369 // int ary[] = { 1, 3, 5 }; 2370 // "ary" transitions from a VariableArrayType to a ConstantArrayType. 2371 if (!VDecl->isInvalidDecl() && (DclT != SavT)) { 2372 VDecl->setType(DclT); 2373 Init->setType(DclT); 2374 } 2375 2376 // Attach the initializer to the decl. 2377 VDecl->setInit(Init); 2378 return; 2379} 2380 2381void Sema::ActOnUninitializedDecl(DeclTy *dcl) { 2382 Decl *RealDecl = static_cast<Decl *>(dcl); 2383 2384 // If there is no declaration, there was an error parsing it. Just ignore it. 2385 if (RealDecl == 0) 2386 return; 2387 2388 if (VarDecl *Var = dyn_cast<VarDecl>(RealDecl)) { 2389 QualType Type = Var->getType(); 2390 // C++ [dcl.init.ref]p3: 2391 // The initializer can be omitted for a reference only in a 2392 // parameter declaration (8.3.5), in the declaration of a 2393 // function return type, in the declaration of a class member 2394 // within its class declaration (9.2), and where the extern 2395 // specifier is explicitly used. 2396 if (Type->isReferenceType() && 2397 Var->getStorageClass() != VarDecl::Extern && 2398 Var->getStorageClass() != VarDecl::PrivateExtern) { 2399 Diag(Var->getLocation(), diag::err_reference_var_requires_init) 2400 << Var->getDeclName() 2401 << SourceRange(Var->getLocation(), Var->getLocation()); 2402 Var->setInvalidDecl(); 2403 return; 2404 } 2405 2406 // C++ [dcl.init]p9: 2407 // 2408 // If no initializer is specified for an object, and the object 2409 // is of (possibly cv-qualified) non-POD class type (or array 2410 // thereof), the object shall be default-initialized; if the 2411 // object is of const-qualified type, the underlying class type 2412 // shall have a user-declared default constructor. 2413 if (getLangOptions().CPlusPlus) { 2414 QualType InitType = Type; 2415 if (const ArrayType *Array = Context.getAsArrayType(Type)) 2416 InitType = Array->getElementType(); 2417 if (Var->getStorageClass() != VarDecl::Extern && 2418 Var->getStorageClass() != VarDecl::PrivateExtern && 2419 InitType->isRecordType()) { 2420 const CXXConstructorDecl *Constructor 2421 = PerformInitializationByConstructor(InitType, 0, 0, 2422 Var->getLocation(), 2423 SourceRange(Var->getLocation(), 2424 Var->getLocation()), 2425 Var->getDeclName(), 2426 IK_Default); 2427 if (!Constructor) 2428 Var->setInvalidDecl(); 2429 } 2430 } 2431 2432#if 0 2433 // FIXME: Temporarily disabled because we are not properly parsing 2434 // linkage specifications on declarations, e.g., 2435 // 2436 // extern "C" const CGPoint CGPointerZero; 2437 // 2438 // C++ [dcl.init]p9: 2439 // 2440 // If no initializer is specified for an object, and the 2441 // object is of (possibly cv-qualified) non-POD class type (or 2442 // array thereof), the object shall be default-initialized; if 2443 // the object is of const-qualified type, the underlying class 2444 // type shall have a user-declared default 2445 // constructor. Otherwise, if no initializer is specified for 2446 // an object, the object and its subobjects, if any, have an 2447 // indeterminate initial value; if the object or any of its 2448 // subobjects are of const-qualified type, the program is 2449 // ill-formed. 2450 // 2451 // This isn't technically an error in C, so we don't diagnose it. 2452 // 2453 // FIXME: Actually perform the POD/user-defined default 2454 // constructor check. 2455 if (getLangOptions().CPlusPlus && 2456 Context.getCanonicalType(Type).isConstQualified() && 2457 Var->getStorageClass() != VarDecl::Extern) 2458 Diag(Var->getLocation(), diag::err_const_var_requires_init) 2459 << Var->getName() 2460 << SourceRange(Var->getLocation(), Var->getLocation()); 2461#endif 2462 } 2463} 2464 2465/// The declarators are chained together backwards, reverse the list. 2466Sema::DeclTy *Sema::FinalizeDeclaratorGroup(Scope *S, DeclTy *group) { 2467 // Often we have single declarators, handle them quickly. 2468 Decl *GroupDecl = static_cast<Decl*>(group); 2469 if (GroupDecl == 0) 2470 return 0; 2471 2472 ScopedDecl *Group = dyn_cast<ScopedDecl>(GroupDecl); 2473 ScopedDecl *NewGroup = 0; 2474 if (Group->getNextDeclarator() == 0) 2475 NewGroup = Group; 2476 else { // reverse the list. 2477 while (Group) { 2478 ScopedDecl *Next = Group->getNextDeclarator(); 2479 Group->setNextDeclarator(NewGroup); 2480 NewGroup = Group; 2481 Group = Next; 2482 } 2483 } 2484 // Perform semantic analysis that depends on having fully processed both 2485 // the declarator and initializer. 2486 for (ScopedDecl *ID = NewGroup; ID; ID = ID->getNextDeclarator()) { 2487 VarDecl *IDecl = dyn_cast<VarDecl>(ID); 2488 if (!IDecl) 2489 continue; 2490 QualType T = IDecl->getType(); 2491 2492 if (T->isVariableArrayType()) { 2493 const VariableArrayType *VAT = Context.getAsVariableArrayType(T); 2494 2495 // FIXME: This won't give the correct result for 2496 // int a[10][n]; 2497 SourceRange SizeRange = VAT->getSizeExpr()->getSourceRange(); 2498 if (IDecl->isFileVarDecl()) { 2499 Diag(IDecl->getLocation(), diag::err_vla_decl_in_file_scope) << 2500 SizeRange; 2501 2502 IDecl->setInvalidDecl(); 2503 } else { 2504 // C99 6.7.5.2p2: If an identifier is declared to be an object with 2505 // static storage duration, it shall not have a variable length array. 2506 if (IDecl->getStorageClass() == VarDecl::Static) { 2507 Diag(IDecl->getLocation(), diag::err_vla_decl_has_static_storage) 2508 << SizeRange; 2509 IDecl->setInvalidDecl(); 2510 } else if (IDecl->getStorageClass() == VarDecl::Extern) { 2511 Diag(IDecl->getLocation(), diag::err_vla_decl_has_extern_linkage) 2512 << SizeRange; 2513 IDecl->setInvalidDecl(); 2514 } 2515 } 2516 } else if (T->isVariablyModifiedType()) { 2517 if (IDecl->isFileVarDecl()) { 2518 Diag(IDecl->getLocation(), diag::err_vm_decl_in_file_scope); 2519 IDecl->setInvalidDecl(); 2520 } else { 2521 if (IDecl->getStorageClass() == VarDecl::Extern) { 2522 Diag(IDecl->getLocation(), diag::err_vm_decl_has_extern_linkage); 2523 IDecl->setInvalidDecl(); 2524 } 2525 } 2526 } 2527 2528 // Block scope. C99 6.7p7: If an identifier for an object is declared with 2529 // no linkage (C99 6.2.2p6), the type for the object shall be complete... 2530 if (IDecl->isBlockVarDecl() && 2531 IDecl->getStorageClass() != VarDecl::Extern) { 2532 if (T->isIncompleteType() && !IDecl->isInvalidDecl()) { 2533 Diag(IDecl->getLocation(), diag::err_typecheck_decl_incomplete_type)<<T; 2534 IDecl->setInvalidDecl(); 2535 } 2536 } 2537 // File scope. C99 6.9.2p2: A declaration of an identifier for and 2538 // object that has file scope without an initializer, and without a 2539 // storage-class specifier or with the storage-class specifier "static", 2540 // constitutes a tentative definition. Note: A tentative definition with 2541 // external linkage is valid (C99 6.2.2p5). 2542 if (isTentativeDefinition(IDecl)) { 2543 if (T->isIncompleteArrayType()) { 2544 // C99 6.9.2 (p2, p5): Implicit initialization causes an incomplete 2545 // array to be completed. Don't issue a diagnostic. 2546 } else if (T->isIncompleteType() && !IDecl->isInvalidDecl()) { 2547 // C99 6.9.2p3: If the declaration of an identifier for an object is 2548 // a tentative definition and has internal linkage (C99 6.2.2p3), the 2549 // declared type shall not be an incomplete type. 2550 Diag(IDecl->getLocation(), diag::err_typecheck_decl_incomplete_type)<<T; 2551 IDecl->setInvalidDecl(); 2552 } 2553 } 2554 if (IDecl->isFileVarDecl()) 2555 CheckForFileScopedRedefinitions(S, IDecl); 2556 } 2557 return NewGroup; 2558} 2559 2560/// ActOnParamDeclarator - Called from Parser::ParseFunctionDeclarator() 2561/// to introduce parameters into function prototype scope. 2562Sema::DeclTy * 2563Sema::ActOnParamDeclarator(Scope *S, Declarator &D) { 2564 const DeclSpec &DS = D.getDeclSpec(); 2565 2566 // Verify C99 6.7.5.3p2: The only SCS allowed is 'register'. 2567 VarDecl::StorageClass StorageClass = VarDecl::None; 2568 if (DS.getStorageClassSpec() == DeclSpec::SCS_register) { 2569 StorageClass = VarDecl::Register; 2570 } else if (DS.getStorageClassSpec() != DeclSpec::SCS_unspecified) { 2571 Diag(DS.getStorageClassSpecLoc(), 2572 diag::err_invalid_storage_class_in_func_decl); 2573 D.getMutableDeclSpec().ClearStorageClassSpecs(); 2574 } 2575 if (DS.isThreadSpecified()) { 2576 Diag(DS.getThreadSpecLoc(), 2577 diag::err_invalid_storage_class_in_func_decl); 2578 D.getMutableDeclSpec().ClearStorageClassSpecs(); 2579 } 2580 2581 // Check that there are no default arguments inside the type of this 2582 // parameter (C++ only). 2583 if (getLangOptions().CPlusPlus) 2584 CheckExtraCXXDefaultArguments(D); 2585 2586 // In this context, we *do not* check D.getInvalidType(). If the declarator 2587 // type was invalid, GetTypeForDeclarator() still returns a "valid" type, 2588 // though it will not reflect the user specified type. 2589 QualType parmDeclType = GetTypeForDeclarator(D, S); 2590 2591 assert(!parmDeclType.isNull() && "GetTypeForDeclarator() returned null type"); 2592 2593 // TODO: CHECK FOR CONFLICTS, multiple decls with same name in one scope. 2594 // Can this happen for params? We already checked that they don't conflict 2595 // among each other. Here they can only shadow globals, which is ok. 2596 IdentifierInfo *II = D.getIdentifier(); 2597 if (Decl *PrevDecl = LookupDecl(II, Decl::IDNS_Ordinary, S)) { 2598 if (PrevDecl->isTemplateParameter()) { 2599 // Maybe we will complain about the shadowed template parameter. 2600 DiagnoseTemplateParameterShadow(D.getIdentifierLoc(), PrevDecl); 2601 // Just pretend that we didn't see the previous declaration. 2602 PrevDecl = 0; 2603 } else if (S->isDeclScope(PrevDecl)) { 2604 Diag(D.getIdentifierLoc(), diag::err_param_redefinition) << II; 2605 2606 // Recover by removing the name 2607 II = 0; 2608 D.SetIdentifier(0, D.getIdentifierLoc()); 2609 } 2610 } 2611 2612 // Perform the default function/array conversion (C99 6.7.5.3p[7,8]). 2613 // Doing the promotion here has a win and a loss. The win is the type for 2614 // both Decl's and DeclRefExpr's will match (a convenient invariant for the 2615 // code generator). The loss is the orginal type isn't preserved. For example: 2616 // 2617 // void func(int parmvardecl[5]) { // convert "int [5]" to "int *" 2618 // int blockvardecl[5]; 2619 // sizeof(parmvardecl); // size == 4 2620 // sizeof(blockvardecl); // size == 20 2621 // } 2622 // 2623 // For expressions, all implicit conversions are captured using the 2624 // ImplicitCastExpr AST node (we have no such mechanism for Decl's). 2625 // 2626 // FIXME: If a source translation tool needs to see the original type, then 2627 // we need to consider storing both types (in ParmVarDecl)... 2628 // 2629 if (parmDeclType->isArrayType()) { 2630 // int x[restrict 4] -> int *restrict 2631 parmDeclType = Context.getArrayDecayedType(parmDeclType); 2632 } else if (parmDeclType->isFunctionType()) 2633 parmDeclType = Context.getPointerType(parmDeclType); 2634 2635 ParmVarDecl *New = ParmVarDecl::Create(Context, CurContext, 2636 D.getIdentifierLoc(), II, 2637 parmDeclType, StorageClass, 2638 0, 0); 2639 2640 if (D.getInvalidType()) 2641 New->setInvalidDecl(); 2642 2643 // Parameter declarators cannot be qualified (C++ [dcl.meaning]p1). 2644 if (D.getCXXScopeSpec().isSet()) { 2645 Diag(D.getIdentifierLoc(), diag::err_qualified_param_declarator) 2646 << D.getCXXScopeSpec().getRange(); 2647 New->setInvalidDecl(); 2648 } 2649 2650 // Add the parameter declaration into this scope. 2651 S->AddDecl(New); 2652 if (II) 2653 IdResolver.AddDecl(New); 2654 2655 ProcessDeclAttributes(New, D); 2656 return New; 2657 2658} 2659 2660Sema::DeclTy *Sema::ActOnStartOfFunctionDef(Scope *FnBodyScope, Declarator &D) { 2661 assert(getCurFunctionDecl() == 0 && "Function parsing confused"); 2662 assert(D.getTypeObject(0).Kind == DeclaratorChunk::Function && 2663 "Not a function declarator!"); 2664 DeclaratorChunk::FunctionTypeInfo &FTI = D.getTypeObject(0).Fun; 2665 2666 // Verify 6.9.1p6: 'every identifier in the identifier list shall be declared' 2667 // for a K&R function. 2668 if (!FTI.hasPrototype) { 2669 for (unsigned i = 0, e = FTI.NumArgs; i != e; ++i) { 2670 if (FTI.ArgInfo[i].Param == 0) { 2671 Diag(FTI.ArgInfo[i].IdentLoc, diag::ext_param_not_declared) 2672 << FTI.ArgInfo[i].Ident; 2673 // Implicitly declare the argument as type 'int' for lack of a better 2674 // type. 2675 DeclSpec DS; 2676 const char* PrevSpec; // unused 2677 DS.SetTypeSpecType(DeclSpec::TST_int, FTI.ArgInfo[i].IdentLoc, 2678 PrevSpec); 2679 Declarator ParamD(DS, Declarator::KNRTypeListContext); 2680 ParamD.SetIdentifier(FTI.ArgInfo[i].Ident, FTI.ArgInfo[i].IdentLoc); 2681 FTI.ArgInfo[i].Param = ActOnParamDeclarator(FnBodyScope, ParamD); 2682 } 2683 } 2684 } else { 2685 // FIXME: Diagnose arguments without names in C. 2686 } 2687 2688 Scope *ParentScope = FnBodyScope->getParent(); 2689 2690 return ActOnStartOfFunctionDef(FnBodyScope, 2691 ActOnDeclarator(ParentScope, D, 0, 2692 /*IsFunctionDefinition=*/true)); 2693} 2694 2695Sema::DeclTy *Sema::ActOnStartOfFunctionDef(Scope *FnBodyScope, DeclTy *D) { 2696 Decl *decl = static_cast<Decl*>(D); 2697 FunctionDecl *FD = cast<FunctionDecl>(decl); 2698 2699 // See if this is a redefinition. 2700 const FunctionDecl *Definition; 2701 if (FD->getBody(Definition)) { 2702 Diag(FD->getLocation(), diag::err_redefinition) << FD->getDeclName(); 2703 Diag(Definition->getLocation(), diag::note_previous_definition); 2704 } 2705 2706 PushDeclContext(FnBodyScope, FD); 2707 2708 // Check the validity of our function parameters 2709 CheckParmsForFunctionDef(FD); 2710 2711 // Introduce our parameters into the function scope 2712 for (unsigned p = 0, NumParams = FD->getNumParams(); p < NumParams; ++p) { 2713 ParmVarDecl *Param = FD->getParamDecl(p); 2714 Param->setOwningFunction(FD); 2715 2716 // If this has an identifier, add it to the scope stack. 2717 if (Param->getIdentifier()) 2718 PushOnScopeChains(Param, FnBodyScope); 2719 } 2720 2721 // Checking attributes of current function definition 2722 // dllimport attribute. 2723 if (FD->getAttr<DLLImportAttr>() && (!FD->getAttr<DLLExportAttr>())) { 2724 // dllimport attribute cannot be applied to definition. 2725 if (!(FD->getAttr<DLLImportAttr>())->isInherited()) { 2726 Diag(FD->getLocation(), 2727 diag::err_attribute_can_be_applied_only_to_symbol_declaration) 2728 << "dllimport"; 2729 FD->setInvalidDecl(); 2730 return FD; 2731 } else { 2732 // If a symbol previously declared dllimport is later defined, the 2733 // attribute is ignored in subsequent references, and a warning is 2734 // emitted. 2735 Diag(FD->getLocation(), 2736 diag::warn_redeclaration_without_attribute_prev_attribute_ignored) 2737 << FD->getNameAsCString() << "dllimport"; 2738 } 2739 } 2740 return FD; 2741} 2742 2743Sema::DeclTy *Sema::ActOnFinishFunctionBody(DeclTy *D, StmtArg BodyArg) { 2744 Decl *dcl = static_cast<Decl *>(D); 2745 Stmt *Body = static_cast<Stmt*>(BodyArg.release()); 2746 if (FunctionDecl *FD = dyn_cast_or_null<FunctionDecl>(dcl)) { 2747 FD->setBody(Body); 2748 assert(FD == getCurFunctionDecl() && "Function parsing confused"); 2749 } else if (ObjCMethodDecl *MD = dyn_cast_or_null<ObjCMethodDecl>(dcl)) { 2750 MD->setBody((Stmt*)Body); 2751 } else 2752 return 0; 2753 PopDeclContext(); 2754 // Verify and clean out per-function state. 2755 2756 // Check goto/label use. 2757 for (llvm::DenseMap<IdentifierInfo*, LabelStmt*>::iterator 2758 I = LabelMap.begin(), E = LabelMap.end(); I != E; ++I) { 2759 // Verify that we have no forward references left. If so, there was a goto 2760 // or address of a label taken, but no definition of it. Label fwd 2761 // definitions are indicated with a null substmt. 2762 if (I->second->getSubStmt() == 0) { 2763 LabelStmt *L = I->second; 2764 // Emit error. 2765 Diag(L->getIdentLoc(), diag::err_undeclared_label_use) << L->getName(); 2766 2767 // At this point, we have gotos that use the bogus label. Stitch it into 2768 // the function body so that they aren't leaked and that the AST is well 2769 // formed. 2770 if (Body) { 2771 L->setSubStmt(new NullStmt(L->getIdentLoc())); 2772 cast<CompoundStmt>(Body)->push_back(L); 2773 } else { 2774 // The whole function wasn't parsed correctly, just delete this. 2775 delete L; 2776 } 2777 } 2778 } 2779 LabelMap.clear(); 2780 2781 return D; 2782} 2783 2784/// ImplicitlyDefineFunction - An undeclared identifier was used in a function 2785/// call, forming a call to an implicitly defined function (per C99 6.5.1p2). 2786ScopedDecl *Sema::ImplicitlyDefineFunction(SourceLocation Loc, 2787 IdentifierInfo &II, Scope *S) { 2788 // Extension in C99. Legal in C90, but warn about it. 2789 if (getLangOptions().C99) 2790 Diag(Loc, diag::ext_implicit_function_decl) << &II; 2791 else 2792 Diag(Loc, diag::warn_implicit_function_decl) << &II; 2793 2794 // FIXME: handle stuff like: 2795 // void foo() { extern float X(); } 2796 // void bar() { X(); } <-- implicit decl for X in another scope. 2797 2798 // Set a Declarator for the implicit definition: int foo(); 2799 const char *Dummy; 2800 DeclSpec DS; 2801 bool Error = DS.SetTypeSpecType(DeclSpec::TST_int, Loc, Dummy); 2802 Error = Error; // Silence warning. 2803 assert(!Error && "Error setting up implicit decl!"); 2804 Declarator D(DS, Declarator::BlockContext); 2805 D.AddTypeInfo(DeclaratorChunk::getFunction(false, false, 0, 0, 0, Loc)); 2806 D.SetIdentifier(&II, Loc); 2807 2808 // Insert this function into translation-unit scope. 2809 2810 DeclContext *PrevDC = CurContext; 2811 CurContext = Context.getTranslationUnitDecl(); 2812 2813 FunctionDecl *FD = 2814 dyn_cast<FunctionDecl>(static_cast<Decl*>(ActOnDeclarator(TUScope, D, 0))); 2815 FD->setImplicit(); 2816 2817 CurContext = PrevDC; 2818 2819 return FD; 2820} 2821 2822 2823TypedefDecl *Sema::ParseTypedefDecl(Scope *S, Declarator &D, QualType T, 2824 ScopedDecl *LastDeclarator) { 2825 assert(D.getIdentifier() && "Wrong callback for declspec without declarator"); 2826 assert(!T.isNull() && "GetTypeForDeclarator() returned null type"); 2827 2828 // Scope manipulation handled by caller. 2829 TypedefDecl *NewTD = TypedefDecl::Create(Context, CurContext, 2830 D.getIdentifierLoc(), 2831 D.getIdentifier(), 2832 T, LastDeclarator); 2833 if (D.getInvalidType()) 2834 NewTD->setInvalidDecl(); 2835 return NewTD; 2836} 2837 2838/// ActOnTag - This is invoked when we see 'struct foo' or 'struct {'. In the 2839/// former case, Name will be non-null. In the later case, Name will be null. 2840/// TagType indicates what kind of tag this is. TK indicates whether this is a 2841/// reference/declaration/definition of a tag. 2842Sema::DeclTy *Sema::ActOnTag(Scope *S, unsigned TagType, TagKind TK, 2843 SourceLocation KWLoc, const CXXScopeSpec &SS, 2844 IdentifierInfo *Name, SourceLocation NameLoc, 2845 AttributeList *Attr, 2846 MultiTemplateParamsArg TemplateParameterLists) { 2847 // If this is not a definition, it must have a name. 2848 assert((Name != 0 || TK == TK_Definition) && 2849 "Nameless record must be a definition!"); 2850 2851 TagDecl::TagKind Kind; 2852 switch (TagType) { 2853 default: assert(0 && "Unknown tag type!"); 2854 case DeclSpec::TST_struct: Kind = TagDecl::TK_struct; break; 2855 case DeclSpec::TST_union: Kind = TagDecl::TK_union; break; 2856 case DeclSpec::TST_class: Kind = TagDecl::TK_class; break; 2857 case DeclSpec::TST_enum: Kind = TagDecl::TK_enum; break; 2858 } 2859 2860 DeclContext *DC = CurContext; 2861 ScopedDecl *PrevDecl = 0; 2862 2863 if (Name && SS.isNotEmpty()) { 2864 // We have a nested-name tag ('struct foo::bar'). 2865 2866 // Check for invalid 'foo::'. 2867 if (SS.isInvalid()) { 2868 Name = 0; 2869 goto CreateNewDecl; 2870 } 2871 2872 DC = static_cast<DeclContext*>(SS.getScopeRep()); 2873 // Look-up name inside 'foo::'. 2874 PrevDecl = dyn_cast_or_null<TagDecl>(LookupDecl(Name, Decl::IDNS_Tag,S,DC)); 2875 2876 // A tag 'foo::bar' must already exist. 2877 if (PrevDecl == 0) { 2878 Diag(NameLoc, diag::err_not_tag_in_scope) << Name << SS.getRange(); 2879 Name = 0; 2880 goto CreateNewDecl; 2881 } 2882 } else { 2883 // If this is a named struct, check to see if there was a previous forward 2884 // declaration or definition. 2885 // Use ScopedDecl instead of TagDecl, because a NamespaceDecl may come up. 2886 PrevDecl = dyn_cast_or_null<ScopedDecl>(LookupDecl(Name, Decl::IDNS_Tag,S)); 2887 2888 if (!getLangOptions().CPlusPlus && TK != TK_Reference) { 2889 // FIXME: This makes sure that we ignore the contexts associated 2890 // with C structs, unions, and enums when looking for a matching 2891 // tag declaration or definition. See the similar lookup tweak 2892 // in Sema::LookupDecl; is there a better way to deal with this? 2893 while (isa<RecordDecl>(DC) || isa<EnumDecl>(DC)) 2894 DC = DC->getParent(); 2895 } 2896 } 2897 2898 if (PrevDecl && PrevDecl->isTemplateParameter()) { 2899 // Maybe we will complain about the shadowed template parameter. 2900 DiagnoseTemplateParameterShadow(NameLoc, PrevDecl); 2901 // Just pretend that we didn't see the previous declaration. 2902 PrevDecl = 0; 2903 } 2904 2905 if (PrevDecl) { 2906 assert((isa<TagDecl>(PrevDecl) || isa<NamespaceDecl>(PrevDecl)) && 2907 "unexpected Decl type"); 2908 if (TagDecl *PrevTagDecl = dyn_cast<TagDecl>(PrevDecl)) { 2909 // If this is a use of a previous tag, or if the tag is already declared 2910 // in the same scope (so that the definition/declaration completes or 2911 // rementions the tag), reuse the decl. 2912 if (TK == TK_Reference || isDeclInScope(PrevDecl, DC, S)) { 2913 // Make sure that this wasn't declared as an enum and now used as a 2914 // struct or something similar. 2915 if (PrevTagDecl->getTagKind() != Kind) { 2916 Diag(KWLoc, diag::err_use_with_wrong_tag) << Name; 2917 Diag(PrevDecl->getLocation(), diag::note_previous_use); 2918 // Recover by making this an anonymous redefinition. 2919 Name = 0; 2920 PrevDecl = 0; 2921 } else { 2922 // If this is a use, just return the declaration we found. 2923 2924 // FIXME: In the future, return a variant or some other clue 2925 // for the consumer of this Decl to know it doesn't own it. 2926 // For our current ASTs this shouldn't be a problem, but will 2927 // need to be changed with DeclGroups. 2928 if (TK == TK_Reference) 2929 return PrevDecl; 2930 2931 // Diagnose attempts to redefine a tag. 2932 if (TK == TK_Definition) { 2933 if (TagDecl *Def = PrevTagDecl->getDefinition(Context)) { 2934 Diag(NameLoc, diag::err_redefinition) << Name; 2935 Diag(Def->getLocation(), diag::note_previous_definition); 2936 // If this is a redefinition, recover by making this struct be 2937 // anonymous, which will make any later references get the previous 2938 // definition. 2939 Name = 0; 2940 PrevDecl = 0; 2941 } 2942 // Okay, this is definition of a previously declared or referenced 2943 // tag PrevDecl. We're going to create a new Decl for it. 2944 } 2945 } 2946 // If we get here we have (another) forward declaration or we 2947 // have a definition. Just create a new decl. 2948 } else { 2949 // If we get here, this is a definition of a new tag type in a nested 2950 // scope, e.g. "struct foo; void bar() { struct foo; }", just create a 2951 // new decl/type. We set PrevDecl to NULL so that the entities 2952 // have distinct types. 2953 PrevDecl = 0; 2954 } 2955 // If we get here, we're going to create a new Decl. If PrevDecl 2956 // is non-NULL, it's a definition of the tag declared by 2957 // PrevDecl. If it's NULL, we have a new definition. 2958 } else { 2959 // PrevDecl is a namespace. 2960 if (isDeclInScope(PrevDecl, DC, S)) { 2961 // The tag name clashes with a namespace name, issue an error and 2962 // recover by making this tag be anonymous. 2963 Diag(NameLoc, diag::err_redefinition_different_kind) << Name; 2964 Diag(PrevDecl->getLocation(), diag::note_previous_definition); 2965 Name = 0; 2966 PrevDecl = 0; 2967 } else { 2968 // The existing declaration isn't relevant to us; we're in a 2969 // new scope, so clear out the previous declaration. 2970 PrevDecl = 0; 2971 } 2972 } 2973 } 2974 2975CreateNewDecl: 2976 2977 // If there is an identifier, use the location of the identifier as the 2978 // location of the decl, otherwise use the location of the struct/union 2979 // keyword. 2980 SourceLocation Loc = NameLoc.isValid() ? NameLoc : KWLoc; 2981 2982 // Otherwise, create a new declaration. If there is a previous 2983 // declaration of the same entity, the two will be linked via 2984 // PrevDecl. 2985 TagDecl *New; 2986 2987 if (Kind == TagDecl::TK_enum) { 2988 // FIXME: Tag decls should be chained to any simultaneous vardecls, e.g.: 2989 // enum X { A, B, C } D; D should chain to X. 2990 New = EnumDecl::Create(Context, DC, Loc, Name, 2991 cast_or_null<EnumDecl>(PrevDecl)); 2992 // If this is an undefined enum, warn. 2993 if (TK != TK_Definition) Diag(Loc, diag::ext_forward_ref_enum); 2994 } else { 2995 // struct/union/class 2996 2997 // FIXME: Tag decls should be chained to any simultaneous vardecls, e.g.: 2998 // struct X { int A; } D; D should chain to X. 2999 if (getLangOptions().CPlusPlus) 3000 // FIXME: Look for a way to use RecordDecl for simple structs. 3001 New = CXXRecordDecl::Create(Context, Kind, DC, Loc, Name, 3002 cast_or_null<CXXRecordDecl>(PrevDecl)); 3003 else 3004 New = RecordDecl::Create(Context, Kind, DC, Loc, Name, 3005 cast_or_null<RecordDecl>(PrevDecl)); 3006 } 3007 3008 if (Kind != TagDecl::TK_enum) { 3009 // Handle #pragma pack: if the #pragma pack stack has non-default 3010 // alignment, make up a packed attribute for this decl. These 3011 // attributes are checked when the ASTContext lays out the 3012 // structure. 3013 // 3014 // It is important for implementing the correct semantics that this 3015 // happen here (in act on tag decl). The #pragma pack stack is 3016 // maintained as a result of parser callbacks which can occur at 3017 // many points during the parsing of a struct declaration (because 3018 // the #pragma tokens are effectively skipped over during the 3019 // parsing of the struct). 3020 if (unsigned Alignment = PackContext.getAlignment()) 3021 New->addAttr(new PackedAttr(Alignment * 8)); 3022 } 3023 3024 if (Attr) 3025 ProcessDeclAttributeList(New, Attr); 3026 3027 // Set the lexical context. If the tag has a C++ scope specifier, the 3028 // lexical context will be different from the semantic context. 3029 New->setLexicalDeclContext(CurContext); 3030 3031 // If this has an identifier, add it to the scope stack. 3032 if (Name) { 3033 // The scope passed in may not be a decl scope. Zip up the scope tree until 3034 // we find one that is. 3035 while ((S->getFlags() & Scope::DeclScope) == 0) 3036 S = S->getParent(); 3037 3038 // Add it to the decl chain. 3039 PushOnScopeChains(New, S); 3040 } else if (getLangOptions().CPlusPlus) { 3041 // FIXME: We also want to do this for C, but if this tag is 3042 // defined within a structure CurContext will point to the context 3043 // enclosing the structure, and we would end up inserting the tag 3044 // type into the wrong place. 3045 CurContext->addDecl(Context, New); 3046 } 3047 3048 return New; 3049} 3050 3051void Sema::ActOnTagStartDefinition(Scope *S, DeclTy *TagD) { 3052 TagDecl *Tag = cast<TagDecl>((Decl *)TagD); 3053 3054 // Enter the tag context. 3055 PushDeclContext(S, Tag); 3056 3057 if (CXXRecordDecl *Record = dyn_cast<CXXRecordDecl>(Tag)) { 3058 FieldCollector->StartClass(); 3059 3060 if (Record->getIdentifier()) { 3061 // C++ [class]p2: 3062 // [...] The class-name is also inserted into the scope of the 3063 // class itself; this is known as the injected-class-name. For 3064 // purposes of access checking, the injected-class-name is treated 3065 // as if it were a public member name. 3066 RecordDecl *InjectedClassName 3067 = CXXRecordDecl::Create(Context, Record->getTagKind(), 3068 CurContext, Record->getLocation(), 3069 Record->getIdentifier(), Record); 3070 InjectedClassName->setImplicit(); 3071 PushOnScopeChains(InjectedClassName, S); 3072 } 3073 } 3074} 3075 3076void Sema::ActOnTagFinishDefinition(Scope *S, DeclTy *TagD) { 3077 TagDecl *Tag = cast<TagDecl>((Decl *)TagD); 3078 3079 if (isa<CXXRecordDecl>(Tag)) 3080 FieldCollector->FinishClass(); 3081 3082 // Exit this scope of this tag's definition. 3083 PopDeclContext(); 3084 3085 // Notify the consumer that we've defined a tag. 3086 Consumer.HandleTagDeclDefinition(Tag); 3087} 3088 3089/// TryToFixInvalidVariablyModifiedType - Helper method to turn variable array 3090/// types into constant array types in certain situations which would otherwise 3091/// be errors (for GCC compatibility). 3092static QualType TryToFixInvalidVariablyModifiedType(QualType T, 3093 ASTContext &Context) { 3094 // This method tries to turn a variable array into a constant 3095 // array even when the size isn't an ICE. This is necessary 3096 // for compatibility with code that depends on gcc's buggy 3097 // constant expression folding, like struct {char x[(int)(char*)2];} 3098 const VariableArrayType* VLATy = dyn_cast<VariableArrayType>(T); 3099 if (!VLATy) return QualType(); 3100 3101 Expr::EvalResult EvalResult; 3102 if (!VLATy->getSizeExpr() || 3103 !VLATy->getSizeExpr()->Evaluate(EvalResult, Context)) 3104 return QualType(); 3105 3106 assert(EvalResult.Val.isInt() && "Size expressions must be integers!"); 3107 llvm::APSInt &Res = EvalResult.Val.getInt(); 3108 if (Res > llvm::APSInt(Res.getBitWidth(), Res.isUnsigned())) 3109 return Context.getConstantArrayType(VLATy->getElementType(), 3110 Res, ArrayType::Normal, 0); 3111 return QualType(); 3112} 3113 3114bool Sema::VerifyBitField(SourceLocation FieldLoc, IdentifierInfo *FieldName, 3115 QualType FieldTy, const Expr *BitWidth) { 3116 // FIXME: 6.7.2.1p4 - verify the field type. 3117 3118 llvm::APSInt Value; 3119 if (VerifyIntegerConstantExpression(BitWidth, &Value)) 3120 return true; 3121 3122 // Zero-width bitfield is ok for anonymous field. 3123 if (Value == 0 && FieldName) 3124 return Diag(FieldLoc, diag::err_bitfield_has_zero_width) << FieldName; 3125 3126 if (Value.isNegative()) 3127 return Diag(FieldLoc, diag::err_bitfield_has_negative_width) << FieldName; 3128 3129 uint64_t TypeSize = Context.getTypeSize(FieldTy); 3130 // FIXME: We won't need the 0 size once we check that the field type is valid. 3131 if (TypeSize && Value.getZExtValue() > TypeSize) 3132 return Diag(FieldLoc, diag::err_bitfield_width_exceeds_type_size) 3133 << FieldName << (unsigned)TypeSize; 3134 3135 return false; 3136} 3137 3138/// ActOnField - Each field of a struct/union/class is passed into this in order 3139/// to create a FieldDecl object for it. 3140Sema::DeclTy *Sema::ActOnField(Scope *S, DeclTy *TagD, 3141 SourceLocation DeclStart, 3142 Declarator &D, ExprTy *BitfieldWidth) { 3143 IdentifierInfo *II = D.getIdentifier(); 3144 Expr *BitWidth = (Expr*)BitfieldWidth; 3145 SourceLocation Loc = DeclStart; 3146 RecordDecl *Record = (RecordDecl *)TagD; 3147 if (II) Loc = D.getIdentifierLoc(); 3148 3149 // FIXME: Unnamed fields can be handled in various different ways, for 3150 // example, unnamed unions inject all members into the struct namespace! 3151 3152 QualType T = GetTypeForDeclarator(D, S); 3153 assert(!T.isNull() && "GetTypeForDeclarator() returned null type"); 3154 bool InvalidDecl = false; 3155 3156 // C99 6.7.2.1p8: A member of a structure or union may have any type other 3157 // than a variably modified type. 3158 if (T->isVariablyModifiedType()) { 3159 QualType FixedTy = TryToFixInvalidVariablyModifiedType(T, Context); 3160 if (!FixedTy.isNull()) { 3161 Diag(Loc, diag::warn_illegal_constant_array_size); 3162 T = FixedTy; 3163 } else { 3164 Diag(Loc, diag::err_typecheck_field_variable_size); 3165 T = Context.IntTy; 3166 InvalidDecl = true; 3167 } 3168 } 3169 3170 if (BitWidth) { 3171 if (VerifyBitField(Loc, II, T, BitWidth)) 3172 InvalidDecl = true; 3173 } else { 3174 // Not a bitfield. 3175 3176 // validate II. 3177 3178 } 3179 3180 // FIXME: Chain fielddecls together. 3181 FieldDecl *NewFD; 3182 3183 NewFD = FieldDecl::Create(Context, Record, 3184 Loc, II, T, BitWidth, 3185 D.getDeclSpec().getStorageClassSpec() == 3186 DeclSpec::SCS_mutable, 3187 /*PrevDecl=*/0); 3188 3189 if (II) { 3190 Decl *PrevDecl 3191 = LookupDecl(II, Decl::IDNS_Member, S, 0, false, false, false); 3192 if (PrevDecl && isDeclInScope(PrevDecl, CurContext, S) 3193 && !isa<TagDecl>(PrevDecl)) { 3194 Diag(Loc, diag::err_duplicate_member) << II; 3195 Diag(PrevDecl->getLocation(), diag::note_previous_declaration); 3196 NewFD->setInvalidDecl(); 3197 Record->setInvalidDecl(); 3198 } 3199 } 3200 3201 if (getLangOptions().CPlusPlus) { 3202 CheckExtraCXXDefaultArguments(D); 3203 if (!T->isPODType()) 3204 cast<CXXRecordDecl>(Record)->setPOD(false); 3205 } 3206 3207 ProcessDeclAttributes(NewFD, D); 3208 3209 if (D.getInvalidType() || InvalidDecl) 3210 NewFD->setInvalidDecl(); 3211 3212 if (II) { 3213 PushOnScopeChains(NewFD, S); 3214 } else 3215 Record->addDecl(Context, NewFD); 3216 3217 return NewFD; 3218} 3219 3220/// TranslateIvarVisibility - Translate visibility from a token ID to an 3221/// AST enum value. 3222static ObjCIvarDecl::AccessControl 3223TranslateIvarVisibility(tok::ObjCKeywordKind ivarVisibility) { 3224 switch (ivarVisibility) { 3225 default: assert(0 && "Unknown visitibility kind"); 3226 case tok::objc_private: return ObjCIvarDecl::Private; 3227 case tok::objc_public: return ObjCIvarDecl::Public; 3228 case tok::objc_protected: return ObjCIvarDecl::Protected; 3229 case tok::objc_package: return ObjCIvarDecl::Package; 3230 } 3231} 3232 3233/// ActOnIvar - Each ivar field of an objective-c class is passed into this 3234/// in order to create an IvarDecl object for it. 3235Sema::DeclTy *Sema::ActOnIvar(Scope *S, 3236 SourceLocation DeclStart, 3237 Declarator &D, ExprTy *BitfieldWidth, 3238 tok::ObjCKeywordKind Visibility) { 3239 3240 IdentifierInfo *II = D.getIdentifier(); 3241 Expr *BitWidth = (Expr*)BitfieldWidth; 3242 SourceLocation Loc = DeclStart; 3243 if (II) Loc = D.getIdentifierLoc(); 3244 3245 // FIXME: Unnamed fields can be handled in various different ways, for 3246 // example, unnamed unions inject all members into the struct namespace! 3247 3248 QualType T = GetTypeForDeclarator(D, S); 3249 assert(!T.isNull() && "GetTypeForDeclarator() returned null type"); 3250 bool InvalidDecl = false; 3251 3252 if (BitWidth) { 3253 // TODO: Validate. 3254 //printf("WARNING: BITFIELDS IGNORED!\n"); 3255 3256 // 6.7.2.1p3 3257 // 6.7.2.1p4 3258 3259 } else { 3260 // Not a bitfield. 3261 3262 // validate II. 3263 3264 } 3265 3266 // C99 6.7.2.1p8: A member of a structure or union may have any type other 3267 // than a variably modified type. 3268 if (T->isVariablyModifiedType()) { 3269 Diag(Loc, diag::err_typecheck_ivar_variable_size); 3270 InvalidDecl = true; 3271 } 3272 3273 // Get the visibility (access control) for this ivar. 3274 ObjCIvarDecl::AccessControl ac = 3275 Visibility != tok::objc_not_keyword ? TranslateIvarVisibility(Visibility) 3276 : ObjCIvarDecl::None; 3277 3278 // Construct the decl. 3279 ObjCIvarDecl *NewID = ObjCIvarDecl::Create(Context, Loc, II, T, ac, 3280 (Expr *)BitfieldWidth); 3281 3282 if (II) { 3283 Decl *PrevDecl 3284 = LookupDecl(II, Decl::IDNS_Member, S, 0, false, false, false); 3285 if (PrevDecl && isDeclInScope(PrevDecl, CurContext, S) 3286 && !isa<TagDecl>(PrevDecl)) { 3287 Diag(Loc, diag::err_duplicate_member) << II; 3288 Diag(PrevDecl->getLocation(), diag::note_previous_declaration); 3289 NewID->setInvalidDecl(); 3290 } 3291 } 3292 3293 // Process attributes attached to the ivar. 3294 ProcessDeclAttributes(NewID, D); 3295 3296 if (D.getInvalidType() || InvalidDecl) 3297 NewID->setInvalidDecl(); 3298 3299 if (II) { 3300 // FIXME: When interfaces are DeclContexts, we'll need to add 3301 // these to the interface. 3302 S->AddDecl(NewID); 3303 IdResolver.AddDecl(NewID); 3304 } 3305 3306 return NewID; 3307} 3308 3309void Sema::ActOnFields(Scope* S, 3310 SourceLocation RecLoc, DeclTy *RecDecl, 3311 DeclTy **Fields, unsigned NumFields, 3312 SourceLocation LBrac, SourceLocation RBrac, 3313 AttributeList *Attr) { 3314 Decl *EnclosingDecl = static_cast<Decl*>(RecDecl); 3315 assert(EnclosingDecl && "missing record or interface decl"); 3316 RecordDecl *Record = dyn_cast<RecordDecl>(EnclosingDecl); 3317 3318 if (Record) { 3319 QualType RecordType = Context.getTypeDeclType(Record); 3320 if (RecordType->getAsRecordType()->getDecl()->isDefinition()) { 3321 RecordDecl *Def = RecordType->getAsRecordType()->getDecl(); 3322 // Diagnose code like: 3323 // struct S { struct S {} X; }; 3324 // We discover this when we complete the outer S. Reject and ignore the 3325 // outer S. 3326 Diag(Def->getLocation(), diag::err_nested_redefinition) 3327 << Def->getDeclName(); 3328 Diag(RecLoc, diag::note_previous_definition); 3329 Record->setInvalidDecl(); 3330 return; 3331 } 3332 } 3333 3334 // Verify that all the fields are okay. 3335 unsigned NumNamedMembers = 0; 3336 llvm::SmallVector<FieldDecl*, 32> RecFields; 3337 3338 for (unsigned i = 0; i != NumFields; ++i) { 3339 FieldDecl *FD = cast_or_null<FieldDecl>(static_cast<Decl*>(Fields[i])); 3340 assert(FD && "missing field decl"); 3341 3342 // Get the type for the field. 3343 Type *FDTy = FD->getType().getTypePtr(); 3344 3345 if (!FD->isAnonymousStructOrUnion()) { 3346 // Remember all fields written by the user. 3347 RecFields.push_back(FD); 3348 } 3349 3350 // C99 6.7.2.1p2 - A field may not be a function type. 3351 if (FDTy->isFunctionType()) { 3352 Diag(FD->getLocation(), diag::err_field_declared_as_function) 3353 << FD->getDeclName(); 3354 FD->setInvalidDecl(); 3355 EnclosingDecl->setInvalidDecl(); 3356 continue; 3357 } 3358 // C99 6.7.2.1p2 - A field may not be an incomplete type except... 3359 if (FDTy->isIncompleteType()) { 3360 if (!Record) { // Incomplete ivar type is always an error. 3361 Diag(FD->getLocation(), diag::err_field_incomplete) <<FD->getDeclName(); 3362 FD->setInvalidDecl(); 3363 EnclosingDecl->setInvalidDecl(); 3364 continue; 3365 } 3366 if (i != NumFields-1 || // ... that the last member ... 3367 !Record->isStruct() || // ... of a structure ... 3368 !FDTy->isArrayType()) { //... may have incomplete array type. 3369 Diag(FD->getLocation(), diag::err_field_incomplete) <<FD->getDeclName(); 3370 FD->setInvalidDecl(); 3371 EnclosingDecl->setInvalidDecl(); 3372 continue; 3373 } 3374 if (NumNamedMembers < 1) { //... must have more than named member ... 3375 Diag(FD->getLocation(), diag::err_flexible_array_empty_struct) 3376 << FD->getDeclName(); 3377 FD->setInvalidDecl(); 3378 EnclosingDecl->setInvalidDecl(); 3379 continue; 3380 } 3381 // Okay, we have a legal flexible array member at the end of the struct. 3382 if (Record) 3383 Record->setHasFlexibleArrayMember(true); 3384 } 3385 /// C99 6.7.2.1p2 - a struct ending in a flexible array member cannot be the 3386 /// field of another structure or the element of an array. 3387 if (const RecordType *FDTTy = FDTy->getAsRecordType()) { 3388 if (FDTTy->getDecl()->hasFlexibleArrayMember()) { 3389 // If this is a member of a union, then entire union becomes "flexible". 3390 if (Record && Record->isUnion()) { 3391 Record->setHasFlexibleArrayMember(true); 3392 } else { 3393 // If this is a struct/class and this is not the last element, reject 3394 // it. Note that GCC supports variable sized arrays in the middle of 3395 // structures. 3396 if (i != NumFields-1) { 3397 Diag(FD->getLocation(), diag::err_variable_sized_type_in_struct) 3398 << FD->getDeclName(); 3399 FD->setInvalidDecl(); 3400 EnclosingDecl->setInvalidDecl(); 3401 continue; 3402 } 3403 // We support flexible arrays at the end of structs in other structs 3404 // as an extension. 3405 Diag(FD->getLocation(), diag::ext_flexible_array_in_struct) 3406 << FD->getDeclName(); 3407 if (Record) 3408 Record->setHasFlexibleArrayMember(true); 3409 } 3410 } 3411 } 3412 /// A field cannot be an Objective-c object 3413 if (FDTy->isObjCInterfaceType()) { 3414 Diag(FD->getLocation(), diag::err_statically_allocated_object) 3415 << FD->getDeclName(); 3416 FD->setInvalidDecl(); 3417 EnclosingDecl->setInvalidDecl(); 3418 continue; 3419 } 3420 // Keep track of the number of named members. 3421 if (FD->getIdentifier()) 3422 ++NumNamedMembers; 3423 } 3424 3425 // Okay, we successfully defined 'Record'. 3426 if (Record) { 3427 Record->completeDefinition(Context); 3428 } else { 3429 ObjCIvarDecl **ClsFields = reinterpret_cast<ObjCIvarDecl**>(&RecFields[0]); 3430 if (ObjCInterfaceDecl *ID = dyn_cast<ObjCInterfaceDecl>(EnclosingDecl)) { 3431 ID->addInstanceVariablesToClass(ClsFields, RecFields.size(), RBrac); 3432 // Must enforce the rule that ivars in the base classes may not be 3433 // duplicates. 3434 if (ID->getSuperClass()) { 3435 for (ObjCInterfaceDecl::ivar_iterator IVI = ID->ivar_begin(), 3436 IVE = ID->ivar_end(); IVI != IVE; ++IVI) { 3437 ObjCIvarDecl* Ivar = (*IVI); 3438 IdentifierInfo *II = Ivar->getIdentifier(); 3439 ObjCIvarDecl* prevIvar = ID->getSuperClass()->FindIvarDeclaration(II); 3440 if (prevIvar) { 3441 Diag(Ivar->getLocation(), diag::err_duplicate_member) << II; 3442 Diag(prevIvar->getLocation(), diag::note_previous_declaration); 3443 } 3444 } 3445 } 3446 } 3447 else if (ObjCImplementationDecl *IMPDecl = 3448 dyn_cast<ObjCImplementationDecl>(EnclosingDecl)) { 3449 assert(IMPDecl && "ActOnFields - missing ObjCImplementationDecl"); 3450 IMPDecl->ObjCAddInstanceVariablesToClassImpl(ClsFields, RecFields.size()); 3451 CheckImplementationIvars(IMPDecl, ClsFields, RecFields.size(), RBrac); 3452 } 3453 } 3454 3455 if (Attr) 3456 ProcessDeclAttributeList(Record, Attr); 3457} 3458 3459Sema::DeclTy *Sema::ActOnEnumConstant(Scope *S, DeclTy *theEnumDecl, 3460 DeclTy *lastEnumConst, 3461 SourceLocation IdLoc, IdentifierInfo *Id, 3462 SourceLocation EqualLoc, ExprTy *val) { 3463 EnumDecl *TheEnumDecl = cast<EnumDecl>(static_cast<Decl*>(theEnumDecl)); 3464 EnumConstantDecl *LastEnumConst = 3465 cast_or_null<EnumConstantDecl>(static_cast<Decl*>(lastEnumConst)); 3466 Expr *Val = static_cast<Expr*>(val); 3467 3468 // The scope passed in may not be a decl scope. Zip up the scope tree until 3469 // we find one that is. 3470 while ((S->getFlags() & Scope::DeclScope) == 0) 3471 S = S->getParent(); 3472 3473 // Verify that there isn't already something declared with this name in this 3474 // scope. 3475 Decl *PrevDecl = LookupDecl(Id, Decl::IDNS_Ordinary, S); 3476 if (PrevDecl && PrevDecl->isTemplateParameter()) { 3477 // Maybe we will complain about the shadowed template parameter. 3478 DiagnoseTemplateParameterShadow(IdLoc, PrevDecl); 3479 // Just pretend that we didn't see the previous declaration. 3480 PrevDecl = 0; 3481 } 3482 3483 if (PrevDecl) { 3484 // When in C++, we may get a TagDecl with the same name; in this case the 3485 // enum constant will 'hide' the tag. 3486 assert((getLangOptions().CPlusPlus || !isa<TagDecl>(PrevDecl)) && 3487 "Received TagDecl when not in C++!"); 3488 if (!isa<TagDecl>(PrevDecl) && isDeclInScope(PrevDecl, CurContext, S)) { 3489 if (isa<EnumConstantDecl>(PrevDecl)) 3490 Diag(IdLoc, diag::err_redefinition_of_enumerator) << Id; 3491 else 3492 Diag(IdLoc, diag::err_redefinition) << Id; 3493 Diag(PrevDecl->getLocation(), diag::note_previous_definition); 3494 delete Val; 3495 return 0; 3496 } 3497 } 3498 3499 llvm::APSInt EnumVal(32); 3500 QualType EltTy; 3501 if (Val) { 3502 // Make sure to promote the operand type to int. 3503 UsualUnaryConversions(Val); 3504 3505 // C99 6.7.2.2p2: Make sure we have an integer constant expression. 3506 SourceLocation ExpLoc; 3507 if (VerifyIntegerConstantExpression(Val, &EnumVal)) { 3508 delete Val; 3509 Val = 0; // Just forget about it. 3510 } else { 3511 EltTy = Val->getType(); 3512 } 3513 } 3514 3515 if (!Val) { 3516 if (LastEnumConst) { 3517 // Assign the last value + 1. 3518 EnumVal = LastEnumConst->getInitVal(); 3519 ++EnumVal; 3520 3521 // Check for overflow on increment. 3522 if (EnumVal < LastEnumConst->getInitVal()) 3523 Diag(IdLoc, diag::warn_enum_value_overflow); 3524 3525 EltTy = LastEnumConst->getType(); 3526 } else { 3527 // First value, set to zero. 3528 EltTy = Context.IntTy; 3529 EnumVal.zextOrTrunc(static_cast<uint32_t>(Context.getTypeSize(EltTy))); 3530 } 3531 } 3532 3533 EnumConstantDecl *New = 3534 EnumConstantDecl::Create(Context, TheEnumDecl, IdLoc, Id, EltTy, 3535 Val, EnumVal, 3536 LastEnumConst); 3537 3538 // Register this decl in the current scope stack. 3539 PushOnScopeChains(New, S); 3540 3541 return New; 3542} 3543 3544// FIXME: For consistency with ActOnFields(), we should have the parser 3545// pass in the source location for the left/right braces. 3546void Sema::ActOnEnumBody(SourceLocation EnumLoc, DeclTy *EnumDeclX, 3547 DeclTy **Elements, unsigned NumElements) { 3548 EnumDecl *Enum = cast<EnumDecl>(static_cast<Decl*>(EnumDeclX)); 3549 QualType EnumType = Context.getTypeDeclType(Enum); 3550 3551 if (EnumType->getAsEnumType()->getDecl()->isDefinition()) { 3552 EnumDecl *Def = EnumType->getAsEnumType()->getDecl(); 3553 // Diagnose code like: 3554 // enum e0 { 3555 // E0 = sizeof(enum e0 { E1 }) 3556 // }; 3557 Diag(Def->getLocation(), diag::err_nested_redefinition) 3558 << Enum->getDeclName(); 3559 Diag(Enum->getLocation(), diag::note_previous_definition); 3560 Enum->setInvalidDecl(); 3561 return; 3562 } 3563 3564 // TODO: If the result value doesn't fit in an int, it must be a long or long 3565 // long value. ISO C does not support this, but GCC does as an extension, 3566 // emit a warning. 3567 unsigned IntWidth = Context.Target.getIntWidth(); 3568 3569 // Verify that all the values are okay, compute the size of the values, and 3570 // reverse the list. 3571 unsigned NumNegativeBits = 0; 3572 unsigned NumPositiveBits = 0; 3573 3574 // Keep track of whether all elements have type int. 3575 bool AllElementsInt = true; 3576 3577 EnumConstantDecl *EltList = 0; 3578 for (unsigned i = 0; i != NumElements; ++i) { 3579 EnumConstantDecl *ECD = 3580 cast_or_null<EnumConstantDecl>(static_cast<Decl*>(Elements[i])); 3581 if (!ECD) continue; // Already issued a diagnostic. 3582 3583 // If the enum value doesn't fit in an int, emit an extension warning. 3584 const llvm::APSInt &InitVal = ECD->getInitVal(); 3585 assert(InitVal.getBitWidth() >= IntWidth && 3586 "Should have promoted value to int"); 3587 if (InitVal.getBitWidth() > IntWidth) { 3588 llvm::APSInt V(InitVal); 3589 V.trunc(IntWidth); 3590 V.extend(InitVal.getBitWidth()); 3591 if (V != InitVal) 3592 Diag(ECD->getLocation(), diag::ext_enum_value_not_int) 3593 << InitVal.toString(10); 3594 } 3595 3596 // Keep track of the size of positive and negative values. 3597 if (InitVal.isUnsigned() || InitVal.isNonNegative()) 3598 NumPositiveBits = std::max(NumPositiveBits, 3599 (unsigned)InitVal.getActiveBits()); 3600 else 3601 NumNegativeBits = std::max(NumNegativeBits, 3602 (unsigned)InitVal.getMinSignedBits()); 3603 3604 // Keep track of whether every enum element has type int (very commmon). 3605 if (AllElementsInt) 3606 AllElementsInt = ECD->getType() == Context.IntTy; 3607 3608 ECD->setNextDeclarator(EltList); 3609 EltList = ECD; 3610 } 3611 3612 // Figure out the type that should be used for this enum. 3613 // FIXME: Support attribute(packed) on enums and -fshort-enums. 3614 QualType BestType; 3615 unsigned BestWidth; 3616 3617 if (NumNegativeBits) { 3618 // If there is a negative value, figure out the smallest integer type (of 3619 // int/long/longlong) that fits. 3620 if (NumNegativeBits <= IntWidth && NumPositiveBits < IntWidth) { 3621 BestType = Context.IntTy; 3622 BestWidth = IntWidth; 3623 } else { 3624 BestWidth = Context.Target.getLongWidth(); 3625 3626 if (NumNegativeBits <= BestWidth && NumPositiveBits < BestWidth) 3627 BestType = Context.LongTy; 3628 else { 3629 BestWidth = Context.Target.getLongLongWidth(); 3630 3631 if (NumNegativeBits > BestWidth || NumPositiveBits >= BestWidth) 3632 Diag(Enum->getLocation(), diag::warn_enum_too_large); 3633 BestType = Context.LongLongTy; 3634 } 3635 } 3636 } else { 3637 // If there is no negative value, figure out which of uint, ulong, ulonglong 3638 // fits. 3639 if (NumPositiveBits <= IntWidth) { 3640 BestType = Context.UnsignedIntTy; 3641 BestWidth = IntWidth; 3642 } else if (NumPositiveBits <= 3643 (BestWidth = Context.Target.getLongWidth())) { 3644 BestType = Context.UnsignedLongTy; 3645 } else { 3646 BestWidth = Context.Target.getLongLongWidth(); 3647 assert(NumPositiveBits <= BestWidth && 3648 "How could an initializer get larger than ULL?"); 3649 BestType = Context.UnsignedLongLongTy; 3650 } 3651 } 3652 3653 // Loop over all of the enumerator constants, changing their types to match 3654 // the type of the enum if needed. 3655 for (unsigned i = 0; i != NumElements; ++i) { 3656 EnumConstantDecl *ECD = 3657 cast_or_null<EnumConstantDecl>(static_cast<Decl*>(Elements[i])); 3658 if (!ECD) continue; // Already issued a diagnostic. 3659 3660 // Standard C says the enumerators have int type, but we allow, as an 3661 // extension, the enumerators to be larger than int size. If each 3662 // enumerator value fits in an int, type it as an int, otherwise type it the 3663 // same as the enumerator decl itself. This means that in "enum { X = 1U }" 3664 // that X has type 'int', not 'unsigned'. 3665 if (ECD->getType() == Context.IntTy) { 3666 // Make sure the init value is signed. 3667 llvm::APSInt IV = ECD->getInitVal(); 3668 IV.setIsSigned(true); 3669 ECD->setInitVal(IV); 3670 3671 if (getLangOptions().CPlusPlus) 3672 // C++ [dcl.enum]p4: Following the closing brace of an 3673 // enum-specifier, each enumerator has the type of its 3674 // enumeration. 3675 ECD->setType(EnumType); 3676 continue; // Already int type. 3677 } 3678 3679 // Determine whether the value fits into an int. 3680 llvm::APSInt InitVal = ECD->getInitVal(); 3681 bool FitsInInt; 3682 if (InitVal.isUnsigned() || !InitVal.isNegative()) 3683 FitsInInt = InitVal.getActiveBits() < IntWidth; 3684 else 3685 FitsInInt = InitVal.getMinSignedBits() <= IntWidth; 3686 3687 // If it fits into an integer type, force it. Otherwise force it to match 3688 // the enum decl type. 3689 QualType NewTy; 3690 unsigned NewWidth; 3691 bool NewSign; 3692 if (FitsInInt) { 3693 NewTy = Context.IntTy; 3694 NewWidth = IntWidth; 3695 NewSign = true; 3696 } else if (ECD->getType() == BestType) { 3697 // Already the right type! 3698 if (getLangOptions().CPlusPlus) 3699 // C++ [dcl.enum]p4: Following the closing brace of an 3700 // enum-specifier, each enumerator has the type of its 3701 // enumeration. 3702 ECD->setType(EnumType); 3703 continue; 3704 } else { 3705 NewTy = BestType; 3706 NewWidth = BestWidth; 3707 NewSign = BestType->isSignedIntegerType(); 3708 } 3709 3710 // Adjust the APSInt value. 3711 InitVal.extOrTrunc(NewWidth); 3712 InitVal.setIsSigned(NewSign); 3713 ECD->setInitVal(InitVal); 3714 3715 // Adjust the Expr initializer and type. 3716 ECD->setInitExpr(new ImplicitCastExpr(NewTy, ECD->getInitExpr(), 3717 /*isLvalue=*/false)); 3718 if (getLangOptions().CPlusPlus) 3719 // C++ [dcl.enum]p4: Following the closing brace of an 3720 // enum-specifier, each enumerator has the type of its 3721 // enumeration. 3722 ECD->setType(EnumType); 3723 else 3724 ECD->setType(NewTy); 3725 } 3726 3727 Enum->completeDefinition(Context, BestType); 3728} 3729 3730Sema::DeclTy *Sema::ActOnFileScopeAsmDecl(SourceLocation Loc, 3731 ExprArg expr) { 3732 StringLiteral *AsmString = cast<StringLiteral>((Expr*)expr.release()); 3733 3734 return FileScopeAsmDecl::Create(Context, Loc, AsmString); 3735} 3736 3737 3738void Sema::ActOnPragmaPack(PragmaPackKind Kind, IdentifierInfo *Name, 3739 ExprTy *alignment, SourceLocation PragmaLoc, 3740 SourceLocation LParenLoc, SourceLocation RParenLoc) { 3741 Expr *Alignment = static_cast<Expr *>(alignment); 3742 3743 // If specified then alignment must be a "small" power of two. 3744 unsigned AlignmentVal = 0; 3745 if (Alignment) { 3746 llvm::APSInt Val; 3747 if (!Alignment->isIntegerConstantExpr(Val, Context) || 3748 !Val.isPowerOf2() || 3749 Val.getZExtValue() > 16) { 3750 Diag(PragmaLoc, diag::warn_pragma_pack_invalid_alignment); 3751 delete Alignment; 3752 return; // Ignore 3753 } 3754 3755 AlignmentVal = (unsigned) Val.getZExtValue(); 3756 } 3757 3758 switch (Kind) { 3759 case Action::PPK_Default: // pack([n]) 3760 PackContext.setAlignment(AlignmentVal); 3761 break; 3762 3763 case Action::PPK_Show: // pack(show) 3764 // Show the current alignment, making sure to show the right value 3765 // for the default. 3766 AlignmentVal = PackContext.getAlignment(); 3767 // FIXME: This should come from the target. 3768 if (AlignmentVal == 0) 3769 AlignmentVal = 8; 3770 Diag(PragmaLoc, diag::warn_pragma_pack_show) << AlignmentVal; 3771 break; 3772 3773 case Action::PPK_Push: // pack(push [, id] [, [n]) 3774 PackContext.push(Name); 3775 // Set the new alignment if specified. 3776 if (Alignment) 3777 PackContext.setAlignment(AlignmentVal); 3778 break; 3779 3780 case Action::PPK_Pop: // pack(pop [, id] [, n]) 3781 // MSDN, C/C++ Preprocessor Reference > Pragma Directives > pack: 3782 // "#pragma pack(pop, identifier, n) is undefined" 3783 if (Alignment && Name) 3784 Diag(PragmaLoc, diag::warn_pragma_pack_pop_identifer_and_alignment); 3785 3786 // Do the pop. 3787 if (!PackContext.pop(Name)) { 3788 // If a name was specified then failure indicates the name 3789 // wasn't found. Otherwise failure indicates the stack was 3790 // empty. 3791 Diag(PragmaLoc, diag::warn_pragma_pack_pop_failed) 3792 << (Name ? "no record matching name" : "stack empty"); 3793 3794 // FIXME: Warn about popping named records as MSVC does. 3795 } else { 3796 // Pop succeeded, set the new alignment if specified. 3797 if (Alignment) 3798 PackContext.setAlignment(AlignmentVal); 3799 } 3800 break; 3801 3802 default: 3803 assert(0 && "Invalid #pragma pack kind."); 3804 } 3805} 3806 3807bool PragmaPackStack::pop(IdentifierInfo *Name) { 3808 if (Stack.empty()) 3809 return false; 3810 3811 // If name is empty just pop top. 3812 if (!Name) { 3813 Alignment = Stack.back().first; 3814 Stack.pop_back(); 3815 return true; 3816 } 3817 3818 // Otherwise, find the named record. 3819 for (unsigned i = Stack.size(); i != 0; ) { 3820 --i; 3821 if (Stack[i].second == Name) { 3822 // Found it, pop up to and including this record. 3823 Alignment = Stack[i].first; 3824 Stack.erase(Stack.begin() + i, Stack.end()); 3825 return true; 3826 } 3827 } 3828 3829 return false; 3830} 3831