SemaDecl.cpp revision bc468ba19c0bad9bf4a40ff39d8fad7e471bfbf5
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 if (getLangOptions().CPlusPlus && (NS & Decl::IDNS_Ordinary)) 267 NS |= Decl::IDNS_Tag; 268 269 if (LookupCtx == 0 && 270 (!getLangOptions().CPlusPlus || (NS == Decl::IDNS_Label))) { 271 // Unqualified name lookup in C/Objective-C and name lookup for 272 // labels in C++ is purely lexical, so search in the 273 // declarations attached to the name. 274 assert(!LookupCtx && "Can't perform qualified name lookup here"); 275 assert(!NamespaceNameOnly && "Can't perform namespace name lookup here"); 276 IdentifierResolver::iterator I 277 = IdResolver.begin(Name, CurContext, LookInParent); 278 279 // Scan up the scope chain looking for a decl that matches this 280 // identifier that is in the appropriate namespace. This search 281 // should not take long, as shadowing of names is uncommon, and 282 // deep shadowing is extremely uncommon. 283 for (; I != IdResolver.end(); ++I) 284 if ((*I)->isInIdentifierNamespace(NS)) 285 return *I; 286 } else if (LookupCtx) { 287 // Perform qualified name lookup into the LookupCtx. 288 // FIXME: Will need to look into base classes and such. 289 DeclContext::lookup_const_iterator I, E; 290 for (llvm::tie(I, E) = LookupCtx->lookup(Context, Name); I != E; ++I) 291 if ((*I)->isInIdentifierNamespace(NS)) { 292 // Ignore non-namespace names if we're only looking for namespaces. 293 if (NamespaceNameOnly && !isa<NamespaceDecl>(*I)) continue; 294 295 return MaybeConstructOverloadSet(Context, I, E); 296 } 297 } else { 298 // Name lookup for ordinary names and tag names in C++ requires 299 // looking into scopes that aren't strictly lexical, and 300 // therefore we walk through the context as well as walking 301 // through the scopes. 302 IdentifierResolver::iterator 303 I = IdResolver.begin(Name, CurContext, true/*LookInParentCtx*/), 304 IEnd = IdResolver.end(); 305 for (; S; S = S->getParent()) { 306 // Check whether the IdResolver has anything in this scope. 307 // FIXME: The isDeclScope check could be expensive. Can we do better? 308 for (; I != IEnd && S->isDeclScope(*I); ++I) { 309 if ((*I)->isInIdentifierNamespace(NS)) { 310 // Ignore non-namespace names if we're only looking for namespaces. 311 if (NamespaceNameOnly && !isa<NamespaceDecl>(*I)) 312 continue; 313 314 // We found something. Look for anything else in our scope 315 // with this same name and in an acceptable identifier 316 // namespace, so that we can construct an overload set if we 317 // need to. 318 IdentifierResolver::iterator LastI = I; 319 for (++LastI; LastI != IEnd; ++LastI) { 320 if (!(*LastI)->isInIdentifierNamespace(NS) || 321 !S->isDeclScope(*LastI)) 322 break; 323 } 324 return MaybeConstructOverloadSet(Context, I, LastI); 325 } 326 } 327 328 // If there is an entity associated with this scope, it's a 329 // DeclContext. We might need to perform qualified lookup into 330 // it. 331 DeclContext *Ctx = static_cast<DeclContext *>(S->getEntity()); 332 while (Ctx && Ctx->isFunctionOrMethod()) 333 Ctx = Ctx->getParent(); 334 while (Ctx && (Ctx->isNamespace() || Ctx->isRecord())) { 335 // Look for declarations of this name in this scope. 336 DeclContext::lookup_const_iterator I, E; 337 for (llvm::tie(I, E) = Ctx->lookup(Context, Name); I != E; ++I) { 338 // FIXME: Cache this result in the IdResolver 339 if ((*I)->isInIdentifierNamespace(NS)) { 340 if (NamespaceNameOnly && !isa<NamespaceDecl>(*I)) 341 continue; 342 return MaybeConstructOverloadSet(Context, I, E); 343 } 344 } 345 346 if (!LookInParent && !Ctx->isTransparentContext()) 347 return 0; 348 349 Ctx = Ctx->getParent(); 350 } 351 } 352 } 353 354 // If we didn't find a use of this identifier, and if the identifier 355 // corresponds to a compiler builtin, create the decl object for the builtin 356 // now, injecting it into translation unit scope, and return it. 357 if (NS & Decl::IDNS_Ordinary) { 358 IdentifierInfo *II = Name.getAsIdentifierInfo(); 359 if (enableLazyBuiltinCreation && II && 360 (LookupCtx == 0 || isa<TranslationUnitDecl>(LookupCtx))) { 361 // If this is a builtin on this (or all) targets, create the decl. 362 if (unsigned BuiltinID = II->getBuiltinID()) 363 return LazilyCreateBuiltin((IdentifierInfo *)II, BuiltinID, S); 364 } 365 if (getLangOptions().ObjC1 && II) { 366 // @interface and @compatibility_alias introduce typedef-like names. 367 // Unlike typedef's, they can only be introduced at file-scope (and are 368 // therefore not scoped decls). They can, however, be shadowed by 369 // other names in IDNS_Ordinary. 370 ObjCInterfaceDeclsTy::iterator IDI = ObjCInterfaceDecls.find(II); 371 if (IDI != ObjCInterfaceDecls.end()) 372 return IDI->second; 373 ObjCAliasTy::iterator I = ObjCAliasDecls.find(II); 374 if (I != ObjCAliasDecls.end()) 375 return I->second->getClassInterface(); 376 } 377 } 378 return 0; 379} 380 381void Sema::InitBuiltinVaListType() { 382 if (!Context.getBuiltinVaListType().isNull()) 383 return; 384 385 IdentifierInfo *VaIdent = &Context.Idents.get("__builtin_va_list"); 386 Decl *VaDecl = LookupDecl(VaIdent, Decl::IDNS_Ordinary, TUScope); 387 TypedefDecl *VaTypedef = cast<TypedefDecl>(VaDecl); 388 Context.setBuiltinVaListType(Context.getTypedefType(VaTypedef)); 389} 390 391/// LazilyCreateBuiltin - The specified Builtin-ID was first used at file scope. 392/// lazily create a decl for it. 393ScopedDecl *Sema::LazilyCreateBuiltin(IdentifierInfo *II, unsigned bid, 394 Scope *S) { 395 Builtin::ID BID = (Builtin::ID)bid; 396 397 if (Context.BuiltinInfo.hasVAListUse(BID)) 398 InitBuiltinVaListType(); 399 400 QualType R = Context.BuiltinInfo.GetBuiltinType(BID, Context); 401 FunctionDecl *New = FunctionDecl::Create(Context, 402 Context.getTranslationUnitDecl(), 403 SourceLocation(), II, R, 404 FunctionDecl::Extern, false, 0); 405 406 // Create Decl objects for each parameter, adding them to the 407 // FunctionDecl. 408 if (FunctionTypeProto *FT = dyn_cast<FunctionTypeProto>(R)) { 409 llvm::SmallVector<ParmVarDecl*, 16> Params; 410 for (unsigned i = 0, e = FT->getNumArgs(); i != e; ++i) 411 Params.push_back(ParmVarDecl::Create(Context, New, SourceLocation(), 0, 412 FT->getArgType(i), VarDecl::None, 0, 413 0)); 414 New->setParams(&Params[0], Params.size()); 415 } 416 417 418 419 // TUScope is the translation-unit scope to insert this function into. 420 PushOnScopeChains(New, TUScope); 421 return New; 422} 423 424/// GetStdNamespace - This method gets the C++ "std" namespace. This is where 425/// everything from the standard library is defined. 426NamespaceDecl *Sema::GetStdNamespace() { 427 if (!StdNamespace) { 428 IdentifierInfo *StdIdent = &PP.getIdentifierTable().get("std"); 429 DeclContext *Global = Context.getTranslationUnitDecl(); 430 Decl *Std = LookupDecl(StdIdent, Decl::IDNS_Tag | Decl::IDNS_Ordinary, 431 0, Global, /*enableLazyBuiltinCreation=*/false); 432 StdNamespace = dyn_cast_or_null<NamespaceDecl>(Std); 433 } 434 return StdNamespace; 435} 436 437/// MergeTypeDefDecl - We just parsed a typedef 'New' which has the same name 438/// and scope as a previous declaration 'Old'. Figure out how to resolve this 439/// situation, merging decls or emitting diagnostics as appropriate. 440/// 441TypedefDecl *Sema::MergeTypeDefDecl(TypedefDecl *New, Decl *OldD) { 442 // Allow multiple definitions for ObjC built-in typedefs. 443 // FIXME: Verify the underlying types are equivalent! 444 if (getLangOptions().ObjC1) { 445 const IdentifierInfo *TypeID = New->getIdentifier(); 446 switch (TypeID->getLength()) { 447 default: break; 448 case 2: 449 if (!TypeID->isStr("id")) 450 break; 451 Context.setObjCIdType(New); 452 return New; 453 case 5: 454 if (!TypeID->isStr("Class")) 455 break; 456 Context.setObjCClassType(New); 457 return New; 458 case 3: 459 if (!TypeID->isStr("SEL")) 460 break; 461 Context.setObjCSelType(New); 462 return New; 463 case 8: 464 if (!TypeID->isStr("Protocol")) 465 break; 466 Context.setObjCProtoType(New->getUnderlyingType()); 467 return New; 468 } 469 // Fall through - the typedef name was not a builtin type. 470 } 471 // Verify the old decl was also a typedef. 472 TypedefDecl *Old = dyn_cast<TypedefDecl>(OldD); 473 if (!Old) { 474 Diag(New->getLocation(), diag::err_redefinition_different_kind) 475 << New->getDeclName(); 476 Diag(OldD->getLocation(), diag::note_previous_definition); 477 return New; 478 } 479 480 // If the typedef types are not identical, reject them in all languages and 481 // with any extensions enabled. 482 if (Old->getUnderlyingType() != New->getUnderlyingType() && 483 Context.getCanonicalType(Old->getUnderlyingType()) != 484 Context.getCanonicalType(New->getUnderlyingType())) { 485 Diag(New->getLocation(), diag::err_redefinition_different_typedef) 486 << New->getUnderlyingType() << Old->getUnderlyingType(); 487 Diag(Old->getLocation(), diag::note_previous_definition); 488 return Old; 489 } 490 491 if (getLangOptions().Microsoft) return New; 492 493 // C++ [dcl.typedef]p2: 494 // In a given non-class scope, a typedef specifier can be used to 495 // redefine the name of any type declared in that scope to refer 496 // to the type to which it already refers. 497 if (getLangOptions().CPlusPlus && !isa<CXXRecordDecl>(CurContext)) 498 return New; 499 500 // In C, redeclaration of a type is a constraint violation (6.7.2.3p1). 501 // Apparently GCC, Intel, and Sun all silently ignore the redeclaration if 502 // *either* declaration is in a system header. The code below implements 503 // this adhoc compatibility rule. FIXME: The following code will not 504 // work properly when compiling ".i" files (containing preprocessed output). 505 if (PP.getDiagnostics().getSuppressSystemWarnings()) { 506 SourceManager &SrcMgr = Context.getSourceManager(); 507 if (SrcMgr.isInSystemHeader(Old->getLocation())) 508 return New; 509 if (SrcMgr.isInSystemHeader(New->getLocation())) 510 return New; 511 } 512 513 Diag(New->getLocation(), diag::err_redefinition) << New->getDeclName(); 514 Diag(Old->getLocation(), diag::note_previous_definition); 515 return New; 516} 517 518/// DeclhasAttr - returns true if decl Declaration already has the target 519/// attribute. 520static bool DeclHasAttr(const Decl *decl, const Attr *target) { 521 for (const Attr *attr = decl->getAttrs(); attr; attr = attr->getNext()) 522 if (attr->getKind() == target->getKind()) 523 return true; 524 525 return false; 526} 527 528/// MergeAttributes - append attributes from the Old decl to the New one. 529static void MergeAttributes(Decl *New, Decl *Old) { 530 Attr *attr = const_cast<Attr*>(Old->getAttrs()), *tmp; 531 532 while (attr) { 533 tmp = attr; 534 attr = attr->getNext(); 535 536 if (!DeclHasAttr(New, tmp)) { 537 tmp->setInherited(true); 538 New->addAttr(tmp); 539 } else { 540 tmp->setNext(0); 541 delete(tmp); 542 } 543 } 544 545 Old->invalidateAttrs(); 546} 547 548/// MergeFunctionDecl - We just parsed a function 'New' from 549/// declarator D which has the same name and scope as a previous 550/// declaration 'Old'. Figure out how to resolve this situation, 551/// merging decls or emitting diagnostics as appropriate. 552/// Redeclaration will be set true if this New is a redeclaration OldD. 553/// 554/// In C++, New and Old must be declarations that are not 555/// overloaded. Use IsOverload to determine whether New and Old are 556/// overloaded, and to select the Old declaration that New should be 557/// merged with. 558FunctionDecl * 559Sema::MergeFunctionDecl(FunctionDecl *New, Decl *OldD, bool &Redeclaration) { 560 assert(!isa<OverloadedFunctionDecl>(OldD) && 561 "Cannot merge with an overloaded function declaration"); 562 563 Redeclaration = false; 564 // Verify the old decl was also a function. 565 FunctionDecl *Old = dyn_cast<FunctionDecl>(OldD); 566 if (!Old) { 567 Diag(New->getLocation(), diag::err_redefinition_different_kind) 568 << New->getDeclName(); 569 Diag(OldD->getLocation(), diag::note_previous_definition); 570 return New; 571 } 572 573 // Determine whether the previous declaration was a definition, 574 // implicit declaration, or a declaration. 575 diag::kind PrevDiag; 576 if (Old->isThisDeclarationADefinition()) 577 PrevDiag = diag::note_previous_definition; 578 else if (Old->isImplicit()) 579 PrevDiag = diag::note_previous_implicit_declaration; 580 else 581 PrevDiag = diag::note_previous_declaration; 582 583 QualType OldQType = Context.getCanonicalType(Old->getType()); 584 QualType NewQType = Context.getCanonicalType(New->getType()); 585 586 if (getLangOptions().CPlusPlus) { 587 // (C++98 13.1p2): 588 // Certain function declarations cannot be overloaded: 589 // -- Function declarations that differ only in the return type 590 // cannot be overloaded. 591 QualType OldReturnType 592 = cast<FunctionType>(OldQType.getTypePtr())->getResultType(); 593 QualType NewReturnType 594 = cast<FunctionType>(NewQType.getTypePtr())->getResultType(); 595 if (OldReturnType != NewReturnType) { 596 Diag(New->getLocation(), diag::err_ovl_diff_return_type); 597 Diag(Old->getLocation(), PrevDiag); 598 Redeclaration = true; 599 return New; 600 } 601 602 const CXXMethodDecl* OldMethod = dyn_cast<CXXMethodDecl>(Old); 603 const CXXMethodDecl* NewMethod = dyn_cast<CXXMethodDecl>(New); 604 if (OldMethod && NewMethod) { 605 // -- Member function declarations with the same name and the 606 // same parameter types cannot be overloaded if any of them 607 // is a static member function declaration. 608 if (OldMethod->isStatic() || NewMethod->isStatic()) { 609 Diag(New->getLocation(), diag::err_ovl_static_nonstatic_member); 610 Diag(Old->getLocation(), PrevDiag); 611 return New; 612 } 613 614 // C++ [class.mem]p1: 615 // [...] A member shall not be declared twice in the 616 // member-specification, except that a nested class or member 617 // class template can be declared and then later defined. 618 if (OldMethod->getLexicalDeclContext() == 619 NewMethod->getLexicalDeclContext()) { 620 unsigned NewDiag; 621 if (isa<CXXConstructorDecl>(OldMethod)) 622 NewDiag = diag::err_constructor_redeclared; 623 else if (isa<CXXDestructorDecl>(NewMethod)) 624 NewDiag = diag::err_destructor_redeclared; 625 else if (isa<CXXConversionDecl>(NewMethod)) 626 NewDiag = diag::err_conv_function_redeclared; 627 else 628 NewDiag = diag::err_member_redeclared; 629 630 Diag(New->getLocation(), NewDiag); 631 Diag(Old->getLocation(), PrevDiag); 632 } 633 } 634 635 // (C++98 8.3.5p3): 636 // All declarations for a function shall agree exactly in both the 637 // return type and the parameter-type-list. 638 if (OldQType == NewQType) { 639 // We have a redeclaration. 640 MergeAttributes(New, Old); 641 Redeclaration = true; 642 return MergeCXXFunctionDecl(New, Old); 643 } 644 645 // Fall through for conflicting redeclarations and redefinitions. 646 } 647 648 // C: Function types need to be compatible, not identical. This handles 649 // duplicate function decls like "void f(int); void f(enum X);" properly. 650 if (!getLangOptions().CPlusPlus && 651 Context.typesAreCompatible(OldQType, NewQType)) { 652 MergeAttributes(New, Old); 653 Redeclaration = true; 654 return New; 655 } 656 657 // A function that has already been declared has been redeclared or defined 658 // with a different type- show appropriate diagnostic 659 660 // TODO: CHECK FOR CONFLICTS, multiple decls with same name in one scope. 661 // TODO: This is totally simplistic. It should handle merging functions 662 // together etc, merging extern int X; int X; ... 663 Diag(New->getLocation(), diag::err_conflicting_types) << New->getDeclName(); 664 Diag(Old->getLocation(), PrevDiag); 665 return New; 666} 667 668/// Predicate for C "tentative" external object definitions (C99 6.9.2). 669static bool isTentativeDefinition(VarDecl *VD) { 670 if (VD->isFileVarDecl()) 671 return (!VD->getInit() && 672 (VD->getStorageClass() == VarDecl::None || 673 VD->getStorageClass() == VarDecl::Static)); 674 return false; 675} 676 677/// CheckForFileScopedRedefinitions - Make sure we forgo redefinition errors 678/// when dealing with C "tentative" external object definitions (C99 6.9.2). 679void Sema::CheckForFileScopedRedefinitions(Scope *S, VarDecl *VD) { 680 bool VDIsTentative = isTentativeDefinition(VD); 681 bool VDIsIncompleteArray = VD->getType()->isIncompleteArrayType(); 682 683 // FIXME: I don't think this will actually see all of the 684 // redefinitions. Can't we check this property on-the-fly? 685 for (IdentifierResolver::iterator 686 I = IdResolver.begin(VD->getIdentifier(), 687 VD->getDeclContext(), false/*LookInParentCtx*/), 688 E = IdResolver.end(); I != E; ++I) { 689 if (*I != VD && isDeclInScope(*I, VD->getDeclContext(), S)) { 690 VarDecl *OldDecl = dyn_cast<VarDecl>(*I); 691 692 // Handle the following case: 693 // int a[10]; 694 // int a[]; - the code below makes sure we set the correct type. 695 // int a[11]; - this is an error, size isn't 10. 696 if (OldDecl && VDIsTentative && VDIsIncompleteArray && 697 OldDecl->getType()->isConstantArrayType()) 698 VD->setType(OldDecl->getType()); 699 700 // Check for "tentative" definitions. We can't accomplish this in 701 // MergeVarDecl since the initializer hasn't been attached. 702 if (!OldDecl || isTentativeDefinition(OldDecl) || VDIsTentative) 703 continue; 704 705 // Handle __private_extern__ just like extern. 706 if (OldDecl->getStorageClass() != VarDecl::Extern && 707 OldDecl->getStorageClass() != VarDecl::PrivateExtern && 708 VD->getStorageClass() != VarDecl::Extern && 709 VD->getStorageClass() != VarDecl::PrivateExtern) { 710 Diag(VD->getLocation(), diag::err_redefinition) << VD->getDeclName(); 711 Diag(OldDecl->getLocation(), diag::note_previous_definition); 712 } 713 } 714 } 715} 716 717/// MergeVarDecl - We just parsed a variable 'New' which has the same name 718/// and scope as a previous declaration 'Old'. Figure out how to resolve this 719/// situation, merging decls or emitting diagnostics as appropriate. 720/// 721/// Tentative definition rules (C99 6.9.2p2) are checked by 722/// FinalizeDeclaratorGroup. Unfortunately, we can't analyze tentative 723/// definitions here, since the initializer hasn't been attached. 724/// 725VarDecl *Sema::MergeVarDecl(VarDecl *New, Decl *OldD) { 726 // Verify the old decl was also a variable. 727 VarDecl *Old = dyn_cast<VarDecl>(OldD); 728 if (!Old) { 729 Diag(New->getLocation(), diag::err_redefinition_different_kind) 730 << New->getDeclName(); 731 Diag(OldD->getLocation(), diag::note_previous_definition); 732 return New; 733 } 734 735 MergeAttributes(New, Old); 736 737 // Verify the types match. 738 QualType OldCType = Context.getCanonicalType(Old->getType()); 739 QualType NewCType = Context.getCanonicalType(New->getType()); 740 if (OldCType != NewCType && !Context.typesAreCompatible(OldCType, NewCType)) { 741 Diag(New->getLocation(), diag::err_redefinition) << New->getDeclName(); 742 Diag(Old->getLocation(), diag::note_previous_definition); 743 return New; 744 } 745 // C99 6.2.2p4: Check if we have a static decl followed by a non-static. 746 if (New->getStorageClass() == VarDecl::Static && 747 (Old->getStorageClass() == VarDecl::None || 748 Old->getStorageClass() == VarDecl::Extern)) { 749 Diag(New->getLocation(), diag::err_static_non_static) << New->getDeclName(); 750 Diag(Old->getLocation(), diag::note_previous_definition); 751 return New; 752 } 753 // C99 6.2.2p4: Check if we have a non-static decl followed by a static. 754 if (New->getStorageClass() != VarDecl::Static && 755 Old->getStorageClass() == VarDecl::Static) { 756 Diag(New->getLocation(), diag::err_non_static_static) << New->getDeclName(); 757 Diag(Old->getLocation(), diag::note_previous_definition); 758 return New; 759 } 760 // Variables with external linkage are analyzed in FinalizeDeclaratorGroup. 761 if (New->getStorageClass() != VarDecl::Extern && !New->isFileVarDecl()) { 762 Diag(New->getLocation(), diag::err_redefinition) << New->getDeclName(); 763 Diag(Old->getLocation(), diag::note_previous_definition); 764 } 765 return New; 766} 767 768/// CheckParmsForFunctionDef - Check that the parameters of the given 769/// function are appropriate for the definition of a function. This 770/// takes care of any checks that cannot be performed on the 771/// declaration itself, e.g., that the types of each of the function 772/// parameters are complete. 773bool Sema::CheckParmsForFunctionDef(FunctionDecl *FD) { 774 bool HasInvalidParm = false; 775 for (unsigned p = 0, NumParams = FD->getNumParams(); p < NumParams; ++p) { 776 ParmVarDecl *Param = FD->getParamDecl(p); 777 778 // C99 6.7.5.3p4: the parameters in a parameter type list in a 779 // function declarator that is part of a function definition of 780 // that function shall not have incomplete type. 781 if (Param->getType()->isIncompleteType() && 782 !Param->isInvalidDecl()) { 783 Diag(Param->getLocation(), diag::err_typecheck_decl_incomplete_type) 784 << Param->getType(); 785 Param->setInvalidDecl(); 786 HasInvalidParm = true; 787 } 788 789 // C99 6.9.1p5: If the declarator includes a parameter type list, the 790 // declaration of each parameter shall include an identifier. 791 if (Param->getIdentifier() == 0 && !getLangOptions().CPlusPlus) 792 Diag(Param->getLocation(), diag::err_parameter_name_omitted); 793 } 794 795 return HasInvalidParm; 796} 797 798/// ParsedFreeStandingDeclSpec - This method is invoked when a declspec with 799/// no declarator (e.g. "struct foo;") is parsed. 800Sema::DeclTy *Sema::ParsedFreeStandingDeclSpec(Scope *S, DeclSpec &DS) { 801 // FIXME: Isn't that more of a parser diagnostic than a sema diagnostic? 802 if (!DS.isMissingDeclaratorOk()) { 803 // FIXME: This diagnostic is emitted even when various previous 804 // errors occurred (see e.g. test/Sema/decl-invalid.c). However, 805 // DeclSpec has no means of communicating this information, and the 806 // responsible parser functions are quite far apart. 807 Diag(DS.getSourceRange().getBegin(), diag::err_no_declarators) 808 << DS.getSourceRange(); 809 return 0; 810 } 811 812 TagDecl *Tag 813 = dyn_cast_or_null<TagDecl>(static_cast<Decl *>(DS.getTypeRep())); 814 if (RecordDecl *Record = dyn_cast_or_null<RecordDecl>(Tag)) { 815 if (!Record->getDeclName() && Record->isDefinition() && 816 !Record->isInvalidDecl()) 817 return BuildAnonymousStructOrUnion(S, DS, Record); 818 } 819 820 return Tag; 821} 822 823/// InjectAnonymousStructOrUnionMembers - Inject the members of the 824/// anonymous struct or union AnonRecord into the owning context Owner 825/// and scope S. This routine will be invoked just after we realize 826/// that an unnamed union or struct is actually an anonymous union or 827/// struct, e.g., 828/// 829/// @code 830/// union { 831/// int i; 832/// float f; 833/// }; // InjectAnonymousStructOrUnionMembers called here to inject i and 834/// // f into the surrounding scope.x 835/// @endcode 836/// 837/// This routine is recursive, injecting the names of nested anonymous 838/// structs/unions into the owning context and scope as well. 839bool Sema::InjectAnonymousStructOrUnionMembers(Scope *S, DeclContext *Owner, 840 RecordDecl *AnonRecord) { 841 bool Invalid = false; 842 for (RecordDecl::field_iterator F = AnonRecord->field_begin(), 843 FEnd = AnonRecord->field_end(); 844 F != FEnd; ++F) { 845 if ((*F)->getDeclName()) { 846 Decl *PrevDecl = LookupDecl((*F)->getDeclName(), Decl::IDNS_Ordinary, 847 S, Owner, false, false, false); 848 if (PrevDecl && !isa<TagDecl>(PrevDecl)) { 849 // C++ [class.union]p2: 850 // The names of the members of an anonymous union shall be 851 // distinct from the names of any other entity in the 852 // scope in which the anonymous union is declared. 853 unsigned diagKind 854 = AnonRecord->isUnion()? diag::err_anonymous_union_member_redecl 855 : diag::err_anonymous_struct_member_redecl; 856 Diag((*F)->getLocation(), diagKind) 857 << (*F)->getDeclName(); 858 Diag(PrevDecl->getLocation(), diag::note_previous_declaration); 859 Invalid = true; 860 } else { 861 // C++ [class.union]p2: 862 // For the purpose of name lookup, after the anonymous union 863 // definition, the members of the anonymous union are 864 // considered to have been defined in the scope in which the 865 // anonymous union is declared. 866 Owner->insert(Context, *F); 867 S->AddDecl(*F); 868 IdResolver.AddDecl(*F); 869 } 870 } else if (const RecordType *InnerRecordType 871 = (*F)->getType()->getAsRecordType()) { 872 RecordDecl *InnerRecord = InnerRecordType->getDecl(); 873 if (InnerRecord->isAnonymousStructOrUnion()) 874 Invalid = Invalid || 875 InjectAnonymousStructOrUnionMembers(S, Owner, InnerRecord); 876 } 877 } 878 879 return Invalid; 880} 881 882/// ActOnAnonymousStructOrUnion - Handle the declaration of an 883/// anonymous structure or union. Anonymous unions are a C++ feature 884/// (C++ [class.union]) and a GNU C extension; anonymous structures 885/// are a GNU C and GNU C++ extension. 886Sema::DeclTy *Sema::BuildAnonymousStructOrUnion(Scope *S, DeclSpec &DS, 887 RecordDecl *Record) { 888 DeclContext *Owner = Record->getDeclContext(); 889 890 // Diagnose whether this anonymous struct/union is an extension. 891 if (Record->isUnion() && !getLangOptions().CPlusPlus) 892 Diag(Record->getLocation(), diag::ext_anonymous_union); 893 else if (!Record->isUnion()) 894 Diag(Record->getLocation(), diag::ext_anonymous_struct); 895 896 // C and C++ require different kinds of checks for anonymous 897 // structs/unions. 898 bool Invalid = false; 899 if (getLangOptions().CPlusPlus) { 900 const char* PrevSpec = 0; 901 // C++ [class.union]p3: 902 // Anonymous unions declared in a named namespace or in the 903 // global namespace shall be declared static. 904 if (DS.getStorageClassSpec() != DeclSpec::SCS_static && 905 (isa<TranslationUnitDecl>(Owner) || 906 (isa<NamespaceDecl>(Owner) && 907 cast<NamespaceDecl>(Owner)->getDeclName()))) { 908 Diag(Record->getLocation(), diag::err_anonymous_union_not_static); 909 Invalid = true; 910 911 // Recover by adding 'static'. 912 DS.SetStorageClassSpec(DeclSpec::SCS_static, SourceLocation(), PrevSpec); 913 } 914 // C++ [class.union]p3: 915 // A storage class is not allowed in a declaration of an 916 // anonymous union in a class scope. 917 else if (DS.getStorageClassSpec() != DeclSpec::SCS_unspecified && 918 isa<RecordDecl>(Owner)) { 919 Diag(DS.getStorageClassSpecLoc(), 920 diag::err_anonymous_union_with_storage_spec); 921 Invalid = true; 922 923 // Recover by removing the storage specifier. 924 DS.SetStorageClassSpec(DeclSpec::SCS_unspecified, SourceLocation(), 925 PrevSpec); 926 } 927 928 // C++ [class.union]p2: 929 // The member-specification of an anonymous union shall only 930 // define non-static data members. [Note: nested types and 931 // functions cannot be declared within an anonymous union. ] 932 for (DeclContext::decl_iterator Mem = Record->decls_begin(), 933 MemEnd = Record->decls_end(); 934 Mem != MemEnd; ++Mem) { 935 if (FieldDecl *FD = dyn_cast<FieldDecl>(*Mem)) { 936 // C++ [class.union]p3: 937 // An anonymous union shall not have private or protected 938 // members (clause 11). 939 if (FD->getAccess() == AS_protected || FD->getAccess() == AS_private) { 940 Diag(FD->getLocation(), diag::err_anonymous_record_nonpublic_member) 941 << (int)Record->isUnion() << (int)(FD->getAccess() == AS_protected); 942 Invalid = true; 943 } 944 } else if ((*Mem)->isImplicit()) { 945 // Any implicit members are fine. 946 } else if (RecordDecl *MemRecord = dyn_cast<RecordDecl>(*Mem)) { 947 if (!MemRecord->isAnonymousStructOrUnion() && 948 MemRecord->getDeclName()) { 949 // This is a nested type declaration. 950 Diag(MemRecord->getLocation(), diag::err_anonymous_record_with_type) 951 << (int)Record->isUnion(); 952 Invalid = true; 953 } 954 } else { 955 // We have something that isn't a non-static data 956 // member. Complain about it. 957 unsigned DK = diag::err_anonymous_record_bad_member; 958 if (isa<TypeDecl>(*Mem)) 959 DK = diag::err_anonymous_record_with_type; 960 else if (isa<FunctionDecl>(*Mem)) 961 DK = diag::err_anonymous_record_with_function; 962 else if (isa<VarDecl>(*Mem)) 963 DK = diag::err_anonymous_record_with_static; 964 Diag((*Mem)->getLocation(), DK) 965 << (int)Record->isUnion(); 966 Invalid = true; 967 } 968 } 969 } else { 970 // FIXME: Check GNU C semantics 971 } 972 973 if (!Record->isUnion() && !Owner->isRecord()) { 974 Diag(Record->getLocation(), diag::err_anonymous_struct_not_member); 975 Invalid = true; 976 } 977 978 // Create a declaration for this anonymous struct/union. 979 ScopedDecl *Anon = 0; 980 if (RecordDecl *OwningClass = dyn_cast<RecordDecl>(Owner)) { 981 Anon = FieldDecl::Create(Context, OwningClass, Record->getLocation(), 982 /*IdentifierInfo=*/0, 983 Context.getTypeDeclType(Record), 984 /*BitWidth=*/0, /*Mutable=*/false, 985 /*PrevDecl=*/0); 986 Anon->setAccess(AS_public); 987 if (getLangOptions().CPlusPlus) 988 FieldCollector->Add(cast<FieldDecl>(Anon)); 989 } else { 990 VarDecl::StorageClass SC; 991 switch (DS.getStorageClassSpec()) { 992 default: assert(0 && "Unknown storage class!"); 993 case DeclSpec::SCS_unspecified: SC = VarDecl::None; break; 994 case DeclSpec::SCS_extern: SC = VarDecl::Extern; break; 995 case DeclSpec::SCS_static: SC = VarDecl::Static; break; 996 case DeclSpec::SCS_auto: SC = VarDecl::Auto; break; 997 case DeclSpec::SCS_register: SC = VarDecl::Register; break; 998 case DeclSpec::SCS_private_extern: SC = VarDecl::PrivateExtern; break; 999 case DeclSpec::SCS_mutable: 1000 // mutable can only appear on non-static class members, so it's always 1001 // an error here 1002 Diag(Record->getLocation(), diag::err_mutable_nonmember); 1003 Invalid = true; 1004 SC = VarDecl::None; 1005 break; 1006 } 1007 1008 Anon = VarDecl::Create(Context, Owner, Record->getLocation(), 1009 /*IdentifierInfo=*/0, 1010 Context.getTypeDeclType(Record), 1011 SC, /*FIXME:LastDeclarator=*/0, 1012 DS.getSourceRange().getBegin()); 1013 } 1014 Anon->setImplicit(); 1015 1016 // Add the anonymous struct/union object to the current 1017 // context. We'll be referencing this object when we refer to one of 1018 // its members. 1019 Owner->addDecl(Context, Anon); 1020 1021 // Inject the members of the anonymous struct/union into the owning 1022 // context and into the identifier resolver chain for name lookup 1023 // purposes. 1024 Invalid = Invalid || InjectAnonymousStructOrUnionMembers(S, Owner, Record); 1025 1026 // Mark this as an anonymous struct/union type. Note that we do not 1027 // do this until after we have already checked and injected the 1028 // members of this anonymous struct/union type, because otherwise 1029 // the members could be injected twice: once by DeclContext when it 1030 // builds its lookup table, and once by 1031 // InjectAnonymousStructOrUnionMembers. 1032 Record->setAnonymousStructOrUnion(true); 1033 1034 if (Invalid) 1035 Anon->setInvalidDecl(); 1036 1037 return Anon; 1038} 1039 1040bool Sema::CheckSingleInitializer(Expr *&Init, QualType DeclType) { 1041 // Get the type before calling CheckSingleAssignmentConstraints(), since 1042 // it can promote the expression. 1043 QualType InitType = Init->getType(); 1044 1045 if (getLangOptions().CPlusPlus) 1046 return PerformCopyInitialization(Init, DeclType, "initializing"); 1047 1048 AssignConvertType ConvTy = CheckSingleAssignmentConstraints(DeclType, Init); 1049 return DiagnoseAssignmentResult(ConvTy, Init->getLocStart(), DeclType, 1050 InitType, Init, "initializing"); 1051} 1052 1053bool Sema::CheckStringLiteralInit(StringLiteral *strLiteral, QualType &DeclT) { 1054 const ArrayType *AT = Context.getAsArrayType(DeclT); 1055 1056 if (const IncompleteArrayType *IAT = dyn_cast<IncompleteArrayType>(AT)) { 1057 // C99 6.7.8p14. We have an array of character type with unknown size 1058 // being initialized to a string literal. 1059 llvm::APSInt ConstVal(32); 1060 ConstVal = strLiteral->getByteLength() + 1; 1061 // Return a new array type (C99 6.7.8p22). 1062 DeclT = Context.getConstantArrayType(IAT->getElementType(), ConstVal, 1063 ArrayType::Normal, 0); 1064 } else { 1065 const ConstantArrayType *CAT = cast<ConstantArrayType>(AT); 1066 // C99 6.7.8p14. We have an array of character type with known size. 1067 // FIXME: Avoid truncation for 64-bit length strings. 1068 if (strLiteral->getByteLength() > (unsigned)CAT->getSize().getZExtValue()) 1069 Diag(strLiteral->getSourceRange().getBegin(), 1070 diag::warn_initializer_string_for_char_array_too_long) 1071 << strLiteral->getSourceRange(); 1072 } 1073 // Set type from "char *" to "constant array of char". 1074 strLiteral->setType(DeclT); 1075 // For now, we always return false (meaning success). 1076 return false; 1077} 1078 1079StringLiteral *Sema::IsStringLiteralInit(Expr *Init, QualType DeclType) { 1080 const ArrayType *AT = Context.getAsArrayType(DeclType); 1081 if (AT && AT->getElementType()->isCharType()) { 1082 return dyn_cast<StringLiteral>(Init); 1083 } 1084 return 0; 1085} 1086 1087bool Sema::CheckInitializerTypes(Expr *&Init, QualType &DeclType, 1088 SourceLocation InitLoc, 1089 DeclarationName InitEntity) { 1090 if (DeclType->isDependentType() || Init->isTypeDependent()) 1091 return false; 1092 1093 // C++ [dcl.init.ref]p1: 1094 // A variable declared to be a T&, that is "reference to type T" 1095 // (8.3.2), shall be initialized by an object, or function, of 1096 // type T or by an object that can be converted into a T. 1097 if (DeclType->isReferenceType()) 1098 return CheckReferenceInit(Init, DeclType); 1099 1100 // C99 6.7.8p3: The type of the entity to be initialized shall be an array 1101 // of unknown size ("[]") or an object type that is not a variable array type. 1102 if (const VariableArrayType *VAT = Context.getAsVariableArrayType(DeclType)) 1103 return Diag(InitLoc, diag::err_variable_object_no_init) 1104 << VAT->getSizeExpr()->getSourceRange(); 1105 1106 InitListExpr *InitList = dyn_cast<InitListExpr>(Init); 1107 if (!InitList) { 1108 // FIXME: Handle wide strings 1109 if (StringLiteral *strLiteral = IsStringLiteralInit(Init, DeclType)) 1110 return CheckStringLiteralInit(strLiteral, DeclType); 1111 1112 // C++ [dcl.init]p14: 1113 // -- If the destination type is a (possibly cv-qualified) class 1114 // type: 1115 if (getLangOptions().CPlusPlus && DeclType->isRecordType()) { 1116 QualType DeclTypeC = Context.getCanonicalType(DeclType); 1117 QualType InitTypeC = Context.getCanonicalType(Init->getType()); 1118 1119 // -- If the initialization is direct-initialization, or if it is 1120 // copy-initialization where the cv-unqualified version of the 1121 // source type is the same class as, or a derived class of, the 1122 // class of the destination, constructors are considered. 1123 if ((DeclTypeC.getUnqualifiedType() == InitTypeC.getUnqualifiedType()) || 1124 IsDerivedFrom(InitTypeC, DeclTypeC)) { 1125 CXXConstructorDecl *Constructor 1126 = PerformInitializationByConstructor(DeclType, &Init, 1, 1127 InitLoc, Init->getSourceRange(), 1128 InitEntity, IK_Copy); 1129 return Constructor == 0; 1130 } 1131 1132 // -- Otherwise (i.e., for the remaining copy-initialization 1133 // cases), user-defined conversion sequences that can 1134 // convert from the source type to the destination type or 1135 // (when a conversion function is used) to a derived class 1136 // thereof are enumerated as described in 13.3.1.4, and the 1137 // best one is chosen through overload resolution 1138 // (13.3). If the conversion cannot be done or is 1139 // ambiguous, the initialization is ill-formed. The 1140 // function selected is called with the initializer 1141 // expression as its argument; if the function is a 1142 // constructor, the call initializes a temporary of the 1143 // destination type. 1144 // FIXME: We're pretending to do copy elision here; return to 1145 // this when we have ASTs for such things. 1146 if (!PerformImplicitConversion(Init, DeclType, "initializing")) 1147 return false; 1148 1149 if (InitEntity) 1150 return Diag(InitLoc, diag::err_cannot_initialize_decl) 1151 << InitEntity << (int)(Init->isLvalue(Context) == Expr::LV_Valid) 1152 << Init->getType() << Init->getSourceRange(); 1153 else 1154 return Diag(InitLoc, diag::err_cannot_initialize_decl_noname) 1155 << DeclType << (int)(Init->isLvalue(Context) == Expr::LV_Valid) 1156 << Init->getType() << Init->getSourceRange(); 1157 } 1158 1159 // C99 6.7.8p16. 1160 if (DeclType->isArrayType()) 1161 return Diag(Init->getLocStart(), diag::err_array_init_list_required) 1162 << Init->getSourceRange(); 1163 1164 return CheckSingleInitializer(Init, DeclType); 1165 } else if (getLangOptions().CPlusPlus) { 1166 // C++ [dcl.init]p14: 1167 // [...] If the class is an aggregate (8.5.1), and the initializer 1168 // is a brace-enclosed list, see 8.5.1. 1169 // 1170 // Note: 8.5.1 is handled below; here, we diagnose the case where 1171 // we have an initializer list and a destination type that is not 1172 // an aggregate. 1173 // FIXME: In C++0x, this is yet another form of initialization. 1174 if (const RecordType *ClassRec = DeclType->getAsRecordType()) { 1175 const CXXRecordDecl *ClassDecl = cast<CXXRecordDecl>(ClassRec->getDecl()); 1176 if (!ClassDecl->isAggregate()) 1177 return Diag(InitLoc, diag::err_init_non_aggr_init_list) 1178 << DeclType << Init->getSourceRange(); 1179 } 1180 } 1181 1182 InitListChecker CheckInitList(this, InitList, DeclType); 1183 return CheckInitList.HadError(); 1184} 1185 1186/// GetNameForDeclarator - Determine the full declaration name for the 1187/// given Declarator. 1188DeclarationName Sema::GetNameForDeclarator(Declarator &D) { 1189 switch (D.getKind()) { 1190 case Declarator::DK_Abstract: 1191 assert(D.getIdentifier() == 0 && "abstract declarators have no name"); 1192 return DeclarationName(); 1193 1194 case Declarator::DK_Normal: 1195 assert (D.getIdentifier() != 0 && "normal declarators have an identifier"); 1196 return DeclarationName(D.getIdentifier()); 1197 1198 case Declarator::DK_Constructor: { 1199 QualType Ty = Context.getTypeDeclType((TypeDecl *)D.getDeclaratorIdType()); 1200 Ty = Context.getCanonicalType(Ty); 1201 return Context.DeclarationNames.getCXXConstructorName(Ty); 1202 } 1203 1204 case Declarator::DK_Destructor: { 1205 QualType Ty = Context.getTypeDeclType((TypeDecl *)D.getDeclaratorIdType()); 1206 Ty = Context.getCanonicalType(Ty); 1207 return Context.DeclarationNames.getCXXDestructorName(Ty); 1208 } 1209 1210 case Declarator::DK_Conversion: { 1211 QualType Ty = QualType::getFromOpaquePtr(D.getDeclaratorIdType()); 1212 Ty = Context.getCanonicalType(Ty); 1213 return Context.DeclarationNames.getCXXConversionFunctionName(Ty); 1214 } 1215 1216 case Declarator::DK_Operator: 1217 assert(D.getIdentifier() == 0 && "operator names have no identifier"); 1218 return Context.DeclarationNames.getCXXOperatorName( 1219 D.getOverloadedOperator()); 1220 } 1221 1222 assert(false && "Unknown name kind"); 1223 return DeclarationName(); 1224} 1225 1226/// isNearlyMatchingMemberFunction - Determine whether the C++ member 1227/// functions Declaration and Definition are "nearly" matching. This 1228/// heuristic is used to improve diagnostics in the case where an 1229/// out-of-line member function definition doesn't match any 1230/// declaration within the class. 1231static bool isNearlyMatchingMemberFunction(ASTContext &Context, 1232 FunctionDecl *Declaration, 1233 FunctionDecl *Definition) { 1234 if (Declaration->param_size() != Definition->param_size()) 1235 return false; 1236 for (unsigned Idx = 0; Idx < Declaration->param_size(); ++Idx) { 1237 QualType DeclParamTy = Declaration->getParamDecl(Idx)->getType(); 1238 QualType DefParamTy = Definition->getParamDecl(Idx)->getType(); 1239 1240 DeclParamTy = Context.getCanonicalType(DeclParamTy.getNonReferenceType()); 1241 DefParamTy = Context.getCanonicalType(DefParamTy.getNonReferenceType()); 1242 if (DeclParamTy.getUnqualifiedType() != DefParamTy.getUnqualifiedType()) 1243 return false; 1244 } 1245 1246 return true; 1247} 1248 1249Sema::DeclTy * 1250Sema::ActOnDeclarator(Scope *S, Declarator &D, DeclTy *lastDecl, 1251 bool IsFunctionDefinition) { 1252 ScopedDecl *LastDeclarator = dyn_cast_or_null<ScopedDecl>((Decl *)lastDecl); 1253 DeclarationName Name = GetNameForDeclarator(D); 1254 1255 // All of these full declarators require an identifier. If it doesn't have 1256 // one, the ParsedFreeStandingDeclSpec action should be used. 1257 if (!Name) { 1258 if (!D.getInvalidType()) // Reject this if we think it is valid. 1259 Diag(D.getDeclSpec().getSourceRange().getBegin(), 1260 diag::err_declarator_need_ident) 1261 << D.getDeclSpec().getSourceRange() << D.getSourceRange(); 1262 return 0; 1263 } 1264 1265 // The scope passed in may not be a decl scope. Zip up the scope tree until 1266 // we find one that is. 1267 while ((S->getFlags() & Scope::DeclScope) == 0 || 1268 (S->getFlags() & Scope::TemplateParamScope) != 0) 1269 S = S->getParent(); 1270 1271 DeclContext *DC; 1272 Decl *PrevDecl; 1273 ScopedDecl *New; 1274 bool InvalidDecl = false; 1275 1276 // See if this is a redefinition of a variable in the same scope. 1277 if (!D.getCXXScopeSpec().isSet()) { 1278 DC = CurContext; 1279 PrevDecl = LookupDecl(Name, Decl::IDNS_Ordinary, S); 1280 } else { // Something like "int foo::x;" 1281 DC = static_cast<DeclContext*>(D.getCXXScopeSpec().getScopeRep()); 1282 PrevDecl = LookupDecl(Name, Decl::IDNS_Ordinary, S, DC); 1283 1284 // C++ 7.3.1.2p2: 1285 // Members (including explicit specializations of templates) of a named 1286 // namespace can also be defined outside that namespace by explicit 1287 // qualification of the name being defined, provided that the entity being 1288 // defined was already declared in the namespace and the definition appears 1289 // after the point of declaration in a namespace that encloses the 1290 // declarations namespace. 1291 // 1292 // Note that we only check the context at this point. We don't yet 1293 // have enough information to make sure that PrevDecl is actually 1294 // the declaration we want to match. For example, given: 1295 // 1296 // class X { 1297 // void f(); 1298 // void f(float); 1299 // }; 1300 // 1301 // void X::f(int) { } // ill-formed 1302 // 1303 // In this case, PrevDecl will point to the overload set 1304 // containing the two f's declared in X, but neither of them 1305 // matches. 1306 if (!CurContext->Encloses(DC)) { 1307 // The qualifying scope doesn't enclose the original declaration. 1308 // Emit diagnostic based on current scope. 1309 SourceLocation L = D.getIdentifierLoc(); 1310 SourceRange R = D.getCXXScopeSpec().getRange(); 1311 if (isa<FunctionDecl>(CurContext)) { 1312 Diag(L, diag::err_invalid_declarator_in_function) << Name << R; 1313 } else { 1314 Diag(L, diag::err_invalid_declarator_scope) 1315 << Name << cast<NamedDecl>(DC)->getDeclName() << R; 1316 } 1317 InvalidDecl = true; 1318 } 1319 } 1320 1321 if (PrevDecl && PrevDecl->isTemplateParameter()) { 1322 // Maybe we will complain about the shadowed template parameter. 1323 InvalidDecl = InvalidDecl 1324 || DiagnoseTemplateParameterShadow(D.getIdentifierLoc(), PrevDecl); 1325 // Just pretend that we didn't see the previous declaration. 1326 PrevDecl = 0; 1327 } 1328 1329 // In C++, the previous declaration we find might be a tag type 1330 // (class or enum). In this case, the new declaration will hide the 1331 // tag type. 1332 if (PrevDecl && PrevDecl->getIdentifierNamespace() == Decl::IDNS_Tag) 1333 PrevDecl = 0; 1334 1335 QualType R = GetTypeForDeclarator(D, S); 1336 assert(!R.isNull() && "GetTypeForDeclarator() returned null type"); 1337 1338 if (D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_typedef) { 1339 // Typedef declarators cannot be qualified (C++ [dcl.meaning]p1). 1340 if (D.getCXXScopeSpec().isSet()) { 1341 Diag(D.getIdentifierLoc(), diag::err_qualified_typedef_declarator) 1342 << D.getCXXScopeSpec().getRange(); 1343 InvalidDecl = true; 1344 // Pretend we didn't see the scope specifier. 1345 DC = 0; 1346 } 1347 1348 // Check that there are no default arguments (C++ only). 1349 if (getLangOptions().CPlusPlus) 1350 CheckExtraCXXDefaultArguments(D); 1351 1352 TypedefDecl *NewTD = ParseTypedefDecl(S, D, R, LastDeclarator); 1353 if (!NewTD) return 0; 1354 1355 // Handle attributes prior to checking for duplicates in MergeVarDecl 1356 ProcessDeclAttributes(NewTD, D); 1357 // Merge the decl with the existing one if appropriate. If the decl is 1358 // in an outer scope, it isn't the same thing. 1359 if (PrevDecl && isDeclInScope(PrevDecl, DC, S)) { 1360 NewTD = MergeTypeDefDecl(NewTD, PrevDecl); 1361 if (NewTD == 0) return 0; 1362 } 1363 New = NewTD; 1364 if (S->getFnParent() == 0) { 1365 // C99 6.7.7p2: If a typedef name specifies a variably modified type 1366 // then it shall have block scope. 1367 if (NewTD->getUnderlyingType()->isVariablyModifiedType()) { 1368 if (NewTD->getUnderlyingType()->isVariableArrayType()) 1369 Diag(D.getIdentifierLoc(), diag::err_vla_decl_in_file_scope); 1370 else 1371 Diag(D.getIdentifierLoc(), diag::err_vm_decl_in_file_scope); 1372 1373 InvalidDecl = true; 1374 } 1375 } 1376 } else if (R.getTypePtr()->isFunctionType()) { 1377 FunctionDecl::StorageClass SC = FunctionDecl::None; 1378 switch (D.getDeclSpec().getStorageClassSpec()) { 1379 default: assert(0 && "Unknown storage class!"); 1380 case DeclSpec::SCS_auto: 1381 case DeclSpec::SCS_register: 1382 case DeclSpec::SCS_mutable: 1383 Diag(D.getIdentifierLoc(), diag::err_typecheck_sclass_func); 1384 InvalidDecl = true; 1385 break; 1386 case DeclSpec::SCS_unspecified: SC = FunctionDecl::None; break; 1387 case DeclSpec::SCS_extern: SC = FunctionDecl::Extern; break; 1388 case DeclSpec::SCS_static: SC = FunctionDecl::Static; break; 1389 case DeclSpec::SCS_private_extern: SC = FunctionDecl::PrivateExtern;break; 1390 } 1391 1392 bool isInline = D.getDeclSpec().isInlineSpecified(); 1393 // bool isVirtual = D.getDeclSpec().isVirtualSpecified(); 1394 bool isExplicit = D.getDeclSpec().isExplicitSpecified(); 1395 1396 FunctionDecl *NewFD; 1397 if (D.getKind() == Declarator::DK_Constructor) { 1398 // This is a C++ constructor declaration. 1399 assert(DC->isRecord() && 1400 "Constructors can only be declared in a member context"); 1401 1402 InvalidDecl = InvalidDecl || CheckConstructorDeclarator(D, R, SC); 1403 1404 // Create the new declaration 1405 NewFD = CXXConstructorDecl::Create(Context, 1406 cast<CXXRecordDecl>(DC), 1407 D.getIdentifierLoc(), Name, R, 1408 isExplicit, isInline, 1409 /*isImplicitlyDeclared=*/false); 1410 1411 if (InvalidDecl) 1412 NewFD->setInvalidDecl(); 1413 } else if (D.getKind() == Declarator::DK_Destructor) { 1414 // This is a C++ destructor declaration. 1415 if (DC->isRecord()) { 1416 InvalidDecl = InvalidDecl || CheckDestructorDeclarator(D, R, SC); 1417 1418 NewFD = CXXDestructorDecl::Create(Context, 1419 cast<CXXRecordDecl>(DC), 1420 D.getIdentifierLoc(), Name, R, 1421 isInline, 1422 /*isImplicitlyDeclared=*/false); 1423 1424 if (InvalidDecl) 1425 NewFD->setInvalidDecl(); 1426 } else { 1427 Diag(D.getIdentifierLoc(), diag::err_destructor_not_member); 1428 1429 // Create a FunctionDecl to satisfy the function definition parsing 1430 // code path. 1431 NewFD = FunctionDecl::Create(Context, DC, D.getIdentifierLoc(), 1432 Name, R, SC, isInline, LastDeclarator, 1433 // FIXME: Move to DeclGroup... 1434 D.getDeclSpec().getSourceRange().getBegin()); 1435 InvalidDecl = true; 1436 NewFD->setInvalidDecl(); 1437 } 1438 } else if (D.getKind() == Declarator::DK_Conversion) { 1439 if (!DC->isRecord()) { 1440 Diag(D.getIdentifierLoc(), 1441 diag::err_conv_function_not_member); 1442 return 0; 1443 } else { 1444 InvalidDecl = InvalidDecl || CheckConversionDeclarator(D, R, SC); 1445 1446 NewFD = CXXConversionDecl::Create(Context, cast<CXXRecordDecl>(DC), 1447 D.getIdentifierLoc(), Name, R, 1448 isInline, isExplicit); 1449 1450 if (InvalidDecl) 1451 NewFD->setInvalidDecl(); 1452 } 1453 } else if (DC->isRecord()) { 1454 // This is a C++ method declaration. 1455 NewFD = CXXMethodDecl::Create(Context, cast<CXXRecordDecl>(DC), 1456 D.getIdentifierLoc(), Name, R, 1457 (SC == FunctionDecl::Static), isInline, 1458 LastDeclarator); 1459 } else { 1460 NewFD = FunctionDecl::Create(Context, DC, 1461 D.getIdentifierLoc(), 1462 Name, R, SC, isInline, LastDeclarator, 1463 // FIXME: Move to DeclGroup... 1464 D.getDeclSpec().getSourceRange().getBegin()); 1465 } 1466 1467 // Set the lexical context. If the declarator has a C++ 1468 // scope specifier, the lexical context will be different 1469 // from the semantic context. 1470 NewFD->setLexicalDeclContext(CurContext); 1471 1472 // Handle GNU asm-label extension (encoded as an attribute). 1473 if (Expr *E = (Expr*) D.getAsmLabel()) { 1474 // The parser guarantees this is a string. 1475 StringLiteral *SE = cast<StringLiteral>(E); 1476 NewFD->addAttr(new AsmLabelAttr(std::string(SE->getStrData(), 1477 SE->getByteLength()))); 1478 } 1479 1480 // Copy the parameter declarations from the declarator D to 1481 // the function declaration NewFD, if they are available. 1482 if (D.getNumTypeObjects() > 0) { 1483 DeclaratorChunk::FunctionTypeInfo &FTI = D.getTypeObject(0).Fun; 1484 1485 // Create Decl objects for each parameter, adding them to the 1486 // FunctionDecl. 1487 llvm::SmallVector<ParmVarDecl*, 16> Params; 1488 1489 // Check for C99 6.7.5.3p10 - foo(void) is a non-varargs 1490 // function that takes no arguments, not a function that takes a 1491 // single void argument. 1492 // We let through "const void" here because Sema::GetTypeForDeclarator 1493 // already checks for that case. 1494 if (FTI.NumArgs == 1 && !FTI.isVariadic && FTI.ArgInfo[0].Ident == 0 && 1495 FTI.ArgInfo[0].Param && 1496 ((ParmVarDecl*)FTI.ArgInfo[0].Param)->getType()->isVoidType()) { 1497 // empty arg list, don't push any params. 1498 ParmVarDecl *Param = (ParmVarDecl*)FTI.ArgInfo[0].Param; 1499 1500 // In C++, the empty parameter-type-list must be spelled "void"; a 1501 // typedef of void is not permitted. 1502 if (getLangOptions().CPlusPlus && 1503 Param->getType().getUnqualifiedType() != Context.VoidTy) { 1504 Diag(Param->getLocation(), diag::ext_param_typedef_of_void); 1505 } 1506 } else if (FTI.NumArgs > 0 && FTI.ArgInfo[0].Param != 0) { 1507 for (unsigned i = 0, e = FTI.NumArgs; i != e; ++i) 1508 Params.push_back((ParmVarDecl *)FTI.ArgInfo[i].Param); 1509 } 1510 1511 NewFD->setParams(&Params[0], Params.size()); 1512 } else if (R->getAsTypedefType()) { 1513 // When we're declaring a function with a typedef, as in the 1514 // following example, we'll need to synthesize (unnamed) 1515 // parameters for use in the declaration. 1516 // 1517 // @code 1518 // typedef void fn(int); 1519 // fn f; 1520 // @endcode 1521 const FunctionTypeProto *FT = R->getAsFunctionTypeProto(); 1522 if (!FT) { 1523 // This is a typedef of a function with no prototype, so we 1524 // don't need to do anything. 1525 } else if ((FT->getNumArgs() == 0) || 1526 (FT->getNumArgs() == 1 && !FT->isVariadic() && 1527 FT->getArgType(0)->isVoidType())) { 1528 // This is a zero-argument function. We don't need to do anything. 1529 } else { 1530 // Synthesize a parameter for each argument type. 1531 llvm::SmallVector<ParmVarDecl*, 16> Params; 1532 for (FunctionTypeProto::arg_type_iterator ArgType = FT->arg_type_begin(); 1533 ArgType != FT->arg_type_end(); ++ArgType) { 1534 Params.push_back(ParmVarDecl::Create(Context, DC, 1535 SourceLocation(), 0, 1536 *ArgType, VarDecl::None, 1537 0, 0)); 1538 } 1539 1540 NewFD->setParams(&Params[0], Params.size()); 1541 } 1542 } 1543 1544 if (CXXConstructorDecl *Constructor = dyn_cast<CXXConstructorDecl>(NewFD)) 1545 InvalidDecl = InvalidDecl || CheckConstructor(Constructor); 1546 else if (isa<CXXDestructorDecl>(NewFD)) { 1547 CXXRecordDecl *Record = cast<CXXRecordDecl>(NewFD->getParent()); 1548 Record->setUserDeclaredDestructor(true); 1549 // C++ [class]p4: A POD-struct is an aggregate class that has [...] no 1550 // user-defined destructor. 1551 Record->setPOD(false); 1552 } else if (CXXConversionDecl *Conversion = 1553 dyn_cast<CXXConversionDecl>(NewFD)) 1554 ActOnConversionDeclarator(Conversion); 1555 1556 // Extra checking for C++ overloaded operators (C++ [over.oper]). 1557 if (NewFD->isOverloadedOperator() && 1558 CheckOverloadedOperatorDeclaration(NewFD)) 1559 NewFD->setInvalidDecl(); 1560 1561 // Merge the decl with the existing one if appropriate. Since C functions 1562 // are in a flat namespace, make sure we consider decls in outer scopes. 1563 if (PrevDecl && 1564 (!getLangOptions().CPlusPlus||isDeclInScope(PrevDecl, DC, S))) { 1565 bool Redeclaration = false; 1566 1567 // If C++, determine whether NewFD is an overload of PrevDecl or 1568 // a declaration that requires merging. If it's an overload, 1569 // there's no more work to do here; we'll just add the new 1570 // function to the scope. 1571 OverloadedFunctionDecl::function_iterator MatchedDecl; 1572 if (!getLangOptions().CPlusPlus || 1573 !IsOverload(NewFD, PrevDecl, MatchedDecl)) { 1574 Decl *OldDecl = PrevDecl; 1575 1576 // If PrevDecl was an overloaded function, extract the 1577 // FunctionDecl that matched. 1578 if (isa<OverloadedFunctionDecl>(PrevDecl)) 1579 OldDecl = *MatchedDecl; 1580 1581 // NewFD and PrevDecl represent declarations that need to be 1582 // merged. 1583 NewFD = MergeFunctionDecl(NewFD, OldDecl, Redeclaration); 1584 1585 if (NewFD == 0) return 0; 1586 if (Redeclaration) { 1587 NewFD->setPreviousDeclaration(cast<FunctionDecl>(OldDecl)); 1588 1589 // An out-of-line member function declaration must also be a 1590 // definition (C++ [dcl.meaning]p1). 1591 if (!IsFunctionDefinition && D.getCXXScopeSpec().isSet() && 1592 !InvalidDecl) { 1593 Diag(NewFD->getLocation(), diag::err_out_of_line_declaration) 1594 << D.getCXXScopeSpec().getRange(); 1595 NewFD->setInvalidDecl(); 1596 } 1597 } 1598 } 1599 1600 if (!Redeclaration && D.getCXXScopeSpec().isSet()) { 1601 // The user tried to provide an out-of-line definition for a 1602 // member function, but there was no such member function 1603 // declared (C++ [class.mfct]p2). For example: 1604 // 1605 // class X { 1606 // void f() const; 1607 // }; 1608 // 1609 // void X::f() { } // ill-formed 1610 // 1611 // Complain about this problem, and attempt to suggest close 1612 // matches (e.g., those that differ only in cv-qualifiers and 1613 // whether the parameter types are references). 1614 Diag(D.getIdentifierLoc(), diag::err_member_def_does_not_match) 1615 << cast<CXXRecordDecl>(DC)->getDeclName() 1616 << D.getCXXScopeSpec().getRange(); 1617 InvalidDecl = true; 1618 1619 PrevDecl = LookupDecl(Name, Decl::IDNS_Ordinary, S, DC); 1620 if (!PrevDecl) { 1621 // Nothing to suggest. 1622 } else if (OverloadedFunctionDecl *Ovl 1623 = dyn_cast<OverloadedFunctionDecl>(PrevDecl)) { 1624 for (OverloadedFunctionDecl::function_iterator 1625 Func = Ovl->function_begin(), 1626 FuncEnd = Ovl->function_end(); 1627 Func != FuncEnd; ++Func) { 1628 if (isNearlyMatchingMemberFunction(Context, *Func, NewFD)) 1629 Diag((*Func)->getLocation(), diag::note_member_def_close_match); 1630 1631 } 1632 } else if (CXXMethodDecl *Method = dyn_cast<CXXMethodDecl>(PrevDecl)) { 1633 // Suggest this no matter how mismatched it is; it's the only 1634 // thing we have. 1635 unsigned diag; 1636 if (isNearlyMatchingMemberFunction(Context, Method, NewFD)) 1637 diag = diag::note_member_def_close_match; 1638 else if (Method->getBody()) 1639 diag = diag::note_previous_definition; 1640 else 1641 diag = diag::note_previous_declaration; 1642 Diag(Method->getLocation(), diag); 1643 } 1644 1645 PrevDecl = 0; 1646 } 1647 } 1648 // Handle attributes. We need to have merged decls when handling attributes 1649 // (for example to check for conflicts, etc). 1650 ProcessDeclAttributes(NewFD, D); 1651 New = NewFD; 1652 1653 if (getLangOptions().CPlusPlus) { 1654 // In C++, check default arguments now that we have merged decls. 1655 CheckCXXDefaultArguments(NewFD); 1656 1657 // An out-of-line member function declaration must also be a 1658 // definition (C++ [dcl.meaning]p1). 1659 if (!IsFunctionDefinition && D.getCXXScopeSpec().isSet() && !InvalidDecl) { 1660 Diag(NewFD->getLocation(), diag::err_out_of_line_declaration) 1661 << D.getCXXScopeSpec().getRange(); 1662 InvalidDecl = true; 1663 } 1664 } 1665 } else { 1666 // Check that there are no default arguments (C++ only). 1667 if (getLangOptions().CPlusPlus) 1668 CheckExtraCXXDefaultArguments(D); 1669 1670 if (R.getTypePtr()->isObjCInterfaceType()) { 1671 Diag(D.getIdentifierLoc(), diag::err_statically_allocated_object) 1672 << D.getIdentifier(); 1673 InvalidDecl = true; 1674 } 1675 1676 VarDecl *NewVD; 1677 VarDecl::StorageClass SC; 1678 switch (D.getDeclSpec().getStorageClassSpec()) { 1679 default: assert(0 && "Unknown storage class!"); 1680 case DeclSpec::SCS_unspecified: SC = VarDecl::None; break; 1681 case DeclSpec::SCS_extern: SC = VarDecl::Extern; break; 1682 case DeclSpec::SCS_static: SC = VarDecl::Static; break; 1683 case DeclSpec::SCS_auto: SC = VarDecl::Auto; break; 1684 case DeclSpec::SCS_register: SC = VarDecl::Register; break; 1685 case DeclSpec::SCS_private_extern: SC = VarDecl::PrivateExtern; break; 1686 case DeclSpec::SCS_mutable: 1687 // mutable can only appear on non-static class members, so it's always 1688 // an error here 1689 Diag(D.getIdentifierLoc(), diag::err_mutable_nonmember); 1690 InvalidDecl = true; 1691 SC = VarDecl::None; 1692 break; 1693 } 1694 1695 IdentifierInfo *II = Name.getAsIdentifierInfo(); 1696 if (!II) { 1697 Diag(D.getIdentifierLoc(), diag::err_bad_variable_name) 1698 << Name.getAsString(); 1699 return 0; 1700 } 1701 1702 if (DC->isRecord()) { 1703 // This is a static data member for a C++ class. 1704 NewVD = CXXClassVarDecl::Create(Context, cast<CXXRecordDecl>(DC), 1705 D.getIdentifierLoc(), II, 1706 R, LastDeclarator); 1707 } else { 1708 bool ThreadSpecified = D.getDeclSpec().isThreadSpecified(); 1709 if (S->getFnParent() == 0) { 1710 // C99 6.9p2: The storage-class specifiers auto and register shall not 1711 // appear in the declaration specifiers in an external declaration. 1712 if (SC == VarDecl::Auto || SC == VarDecl::Register) { 1713 Diag(D.getIdentifierLoc(), diag::err_typecheck_sclass_fscope); 1714 InvalidDecl = true; 1715 } 1716 } 1717 NewVD = VarDecl::Create(Context, DC, D.getIdentifierLoc(), 1718 II, R, SC, LastDeclarator, 1719 // FIXME: Move to DeclGroup... 1720 D.getDeclSpec().getSourceRange().getBegin()); 1721 NewVD->setThreadSpecified(ThreadSpecified); 1722 } 1723 // Handle attributes prior to checking for duplicates in MergeVarDecl 1724 ProcessDeclAttributes(NewVD, D); 1725 1726 // Handle GNU asm-label extension (encoded as an attribute). 1727 if (Expr *E = (Expr*) D.getAsmLabel()) { 1728 // The parser guarantees this is a string. 1729 StringLiteral *SE = cast<StringLiteral>(E); 1730 NewVD->addAttr(new AsmLabelAttr(std::string(SE->getStrData(), 1731 SE->getByteLength()))); 1732 } 1733 1734 // Emit an error if an address space was applied to decl with local storage. 1735 // This includes arrays of objects with address space qualifiers, but not 1736 // automatic variables that point to other address spaces. 1737 // ISO/IEC TR 18037 S5.1.2 1738 if (NewVD->hasLocalStorage() && (NewVD->getType().getAddressSpace() != 0)) { 1739 Diag(D.getIdentifierLoc(), diag::err_as_qualified_auto_decl); 1740 InvalidDecl = true; 1741 } 1742 // Merge the decl with the existing one if appropriate. If the decl is 1743 // in an outer scope, it isn't the same thing. 1744 if (PrevDecl && isDeclInScope(PrevDecl, DC, S)) { 1745 if (isa<FieldDecl>(PrevDecl) && D.getCXXScopeSpec().isSet()) { 1746 // The user tried to define a non-static data member 1747 // out-of-line (C++ [dcl.meaning]p1). 1748 Diag(NewVD->getLocation(), diag::err_nonstatic_member_out_of_line) 1749 << D.getCXXScopeSpec().getRange(); 1750 NewVD->Destroy(Context); 1751 return 0; 1752 } 1753 1754 NewVD = MergeVarDecl(NewVD, PrevDecl); 1755 if (NewVD == 0) return 0; 1756 1757 if (D.getCXXScopeSpec().isSet()) { 1758 // No previous declaration in the qualifying scope. 1759 Diag(D.getIdentifierLoc(), diag::err_typecheck_no_member) 1760 << Name << D.getCXXScopeSpec().getRange(); 1761 InvalidDecl = true; 1762 } 1763 } 1764 New = NewVD; 1765 } 1766 1767 // Set the lexical context. If the declarator has a C++ scope specifier, the 1768 // lexical context will be different from the semantic context. 1769 New->setLexicalDeclContext(CurContext); 1770 1771 // If this has an identifier, add it to the scope stack. 1772 if (Name) 1773 PushOnScopeChains(New, S); 1774 // If any semantic error occurred, mark the decl as invalid. 1775 if (D.getInvalidType() || InvalidDecl) 1776 New->setInvalidDecl(); 1777 1778 return New; 1779} 1780 1781void Sema::InitializerElementNotConstant(const Expr *Init) { 1782 Diag(Init->getExprLoc(), diag::err_init_element_not_constant) 1783 << Init->getSourceRange(); 1784} 1785 1786bool Sema::CheckAddressConstantExpressionLValue(const Expr* Init) { 1787 switch (Init->getStmtClass()) { 1788 default: 1789 InitializerElementNotConstant(Init); 1790 return true; 1791 case Expr::ParenExprClass: { 1792 const ParenExpr* PE = cast<ParenExpr>(Init); 1793 return CheckAddressConstantExpressionLValue(PE->getSubExpr()); 1794 } 1795 case Expr::CompoundLiteralExprClass: 1796 return cast<CompoundLiteralExpr>(Init)->isFileScope(); 1797 case Expr::DeclRefExprClass: 1798 case Expr::QualifiedDeclRefExprClass: { 1799 const Decl *D = cast<DeclRefExpr>(Init)->getDecl(); 1800 if (const VarDecl *VD = dyn_cast<VarDecl>(D)) { 1801 if (VD->hasGlobalStorage()) 1802 return false; 1803 InitializerElementNotConstant(Init); 1804 return true; 1805 } 1806 if (isa<FunctionDecl>(D)) 1807 return false; 1808 InitializerElementNotConstant(Init); 1809 return true; 1810 } 1811 case Expr::MemberExprClass: { 1812 const MemberExpr *M = cast<MemberExpr>(Init); 1813 if (M->isArrow()) 1814 return CheckAddressConstantExpression(M->getBase()); 1815 return CheckAddressConstantExpressionLValue(M->getBase()); 1816 } 1817 case Expr::ArraySubscriptExprClass: { 1818 // FIXME: Should we pedwarn for "x[0+0]" (where x is a pointer)? 1819 const ArraySubscriptExpr *ASE = cast<ArraySubscriptExpr>(Init); 1820 return CheckAddressConstantExpression(ASE->getBase()) || 1821 CheckArithmeticConstantExpression(ASE->getIdx()); 1822 } 1823 case Expr::StringLiteralClass: 1824 case Expr::PredefinedExprClass: 1825 return false; 1826 case Expr::UnaryOperatorClass: { 1827 const UnaryOperator *Exp = cast<UnaryOperator>(Init); 1828 1829 // C99 6.6p9 1830 if (Exp->getOpcode() == UnaryOperator::Deref) 1831 return CheckAddressConstantExpression(Exp->getSubExpr()); 1832 1833 InitializerElementNotConstant(Init); 1834 return true; 1835 } 1836 } 1837} 1838 1839bool Sema::CheckAddressConstantExpression(const Expr* Init) { 1840 switch (Init->getStmtClass()) { 1841 default: 1842 InitializerElementNotConstant(Init); 1843 return true; 1844 case Expr::ParenExprClass: 1845 return CheckAddressConstantExpression(cast<ParenExpr>(Init)->getSubExpr()); 1846 case Expr::StringLiteralClass: 1847 case Expr::ObjCStringLiteralClass: 1848 return false; 1849 case Expr::CallExprClass: 1850 case Expr::CXXOperatorCallExprClass: 1851 // __builtin___CFStringMakeConstantString is a valid constant l-value. 1852 if (cast<CallExpr>(Init)->isBuiltinCall() == 1853 Builtin::BI__builtin___CFStringMakeConstantString) 1854 return false; 1855 1856 InitializerElementNotConstant(Init); 1857 return true; 1858 1859 case Expr::UnaryOperatorClass: { 1860 const UnaryOperator *Exp = cast<UnaryOperator>(Init); 1861 1862 // C99 6.6p9 1863 if (Exp->getOpcode() == UnaryOperator::AddrOf) 1864 return CheckAddressConstantExpressionLValue(Exp->getSubExpr()); 1865 1866 if (Exp->getOpcode() == UnaryOperator::Extension) 1867 return CheckAddressConstantExpression(Exp->getSubExpr()); 1868 1869 InitializerElementNotConstant(Init); 1870 return true; 1871 } 1872 case Expr::BinaryOperatorClass: { 1873 // FIXME: Should we pedwarn for expressions like "a + 1 + 2"? 1874 const BinaryOperator *Exp = cast<BinaryOperator>(Init); 1875 1876 Expr *PExp = Exp->getLHS(); 1877 Expr *IExp = Exp->getRHS(); 1878 if (IExp->getType()->isPointerType()) 1879 std::swap(PExp, IExp); 1880 1881 // FIXME: Should we pedwarn if IExp isn't an integer constant expression? 1882 return CheckAddressConstantExpression(PExp) || 1883 CheckArithmeticConstantExpression(IExp); 1884 } 1885 case Expr::ImplicitCastExprClass: 1886 case Expr::CStyleCastExprClass: { 1887 const Expr* SubExpr = cast<CastExpr>(Init)->getSubExpr(); 1888 if (Init->getStmtClass() == Expr::ImplicitCastExprClass) { 1889 // Check for implicit promotion 1890 if (SubExpr->getType()->isFunctionType() || 1891 SubExpr->getType()->isArrayType()) 1892 return CheckAddressConstantExpressionLValue(SubExpr); 1893 } 1894 1895 // Check for pointer->pointer cast 1896 if (SubExpr->getType()->isPointerType()) 1897 return CheckAddressConstantExpression(SubExpr); 1898 1899 if (SubExpr->getType()->isIntegralType()) { 1900 // Check for the special-case of a pointer->int->pointer cast; 1901 // this isn't standard, but some code requires it. See 1902 // PR2720 for an example. 1903 if (const CastExpr* SubCast = dyn_cast<CastExpr>(SubExpr)) { 1904 if (SubCast->getSubExpr()->getType()->isPointerType()) { 1905 unsigned IntWidth = Context.getIntWidth(SubCast->getType()); 1906 unsigned PointerWidth = Context.getTypeSize(Context.VoidPtrTy); 1907 if (IntWidth >= PointerWidth) { 1908 return CheckAddressConstantExpression(SubCast->getSubExpr()); 1909 } 1910 } 1911 } 1912 } 1913 if (SubExpr->getType()->isArithmeticType()) { 1914 return CheckArithmeticConstantExpression(SubExpr); 1915 } 1916 1917 InitializerElementNotConstant(Init); 1918 return true; 1919 } 1920 case Expr::ConditionalOperatorClass: { 1921 // FIXME: Should we pedwarn here? 1922 const ConditionalOperator *Exp = cast<ConditionalOperator>(Init); 1923 if (!Exp->getCond()->getType()->isArithmeticType()) { 1924 InitializerElementNotConstant(Init); 1925 return true; 1926 } 1927 if (CheckArithmeticConstantExpression(Exp->getCond())) 1928 return true; 1929 if (Exp->getLHS() && 1930 CheckAddressConstantExpression(Exp->getLHS())) 1931 return true; 1932 return CheckAddressConstantExpression(Exp->getRHS()); 1933 } 1934 case Expr::AddrLabelExprClass: 1935 return false; 1936 } 1937} 1938 1939static const Expr* FindExpressionBaseAddress(const Expr* E); 1940 1941static const Expr* FindExpressionBaseAddressLValue(const Expr* E) { 1942 switch (E->getStmtClass()) { 1943 default: 1944 return E; 1945 case Expr::ParenExprClass: { 1946 const ParenExpr* PE = cast<ParenExpr>(E); 1947 return FindExpressionBaseAddressLValue(PE->getSubExpr()); 1948 } 1949 case Expr::MemberExprClass: { 1950 const MemberExpr *M = cast<MemberExpr>(E); 1951 if (M->isArrow()) 1952 return FindExpressionBaseAddress(M->getBase()); 1953 return FindExpressionBaseAddressLValue(M->getBase()); 1954 } 1955 case Expr::ArraySubscriptExprClass: { 1956 const ArraySubscriptExpr *ASE = cast<ArraySubscriptExpr>(E); 1957 return FindExpressionBaseAddress(ASE->getBase()); 1958 } 1959 case Expr::UnaryOperatorClass: { 1960 const UnaryOperator *Exp = cast<UnaryOperator>(E); 1961 1962 if (Exp->getOpcode() == UnaryOperator::Deref) 1963 return FindExpressionBaseAddress(Exp->getSubExpr()); 1964 1965 return E; 1966 } 1967 } 1968} 1969 1970static const Expr* FindExpressionBaseAddress(const Expr* E) { 1971 switch (E->getStmtClass()) { 1972 default: 1973 return E; 1974 case Expr::ParenExprClass: { 1975 const ParenExpr* PE = cast<ParenExpr>(E); 1976 return FindExpressionBaseAddress(PE->getSubExpr()); 1977 } 1978 case Expr::UnaryOperatorClass: { 1979 const UnaryOperator *Exp = cast<UnaryOperator>(E); 1980 1981 // C99 6.6p9 1982 if (Exp->getOpcode() == UnaryOperator::AddrOf) 1983 return FindExpressionBaseAddressLValue(Exp->getSubExpr()); 1984 1985 if (Exp->getOpcode() == UnaryOperator::Extension) 1986 return FindExpressionBaseAddress(Exp->getSubExpr()); 1987 1988 return E; 1989 } 1990 case Expr::BinaryOperatorClass: { 1991 const BinaryOperator *Exp = cast<BinaryOperator>(E); 1992 1993 Expr *PExp = Exp->getLHS(); 1994 Expr *IExp = Exp->getRHS(); 1995 if (IExp->getType()->isPointerType()) 1996 std::swap(PExp, IExp); 1997 1998 return FindExpressionBaseAddress(PExp); 1999 } 2000 case Expr::ImplicitCastExprClass: { 2001 const Expr* SubExpr = cast<ImplicitCastExpr>(E)->getSubExpr(); 2002 2003 // Check for implicit promotion 2004 if (SubExpr->getType()->isFunctionType() || 2005 SubExpr->getType()->isArrayType()) 2006 return FindExpressionBaseAddressLValue(SubExpr); 2007 2008 // Check for pointer->pointer cast 2009 if (SubExpr->getType()->isPointerType()) 2010 return FindExpressionBaseAddress(SubExpr); 2011 2012 // We assume that we have an arithmetic expression here; 2013 // if we don't, we'll figure it out later 2014 return 0; 2015 } 2016 case Expr::CStyleCastExprClass: { 2017 const Expr* SubExpr = cast<CastExpr>(E)->getSubExpr(); 2018 2019 // Check for pointer->pointer cast 2020 if (SubExpr->getType()->isPointerType()) 2021 return FindExpressionBaseAddress(SubExpr); 2022 2023 // We assume that we have an arithmetic expression here; 2024 // if we don't, we'll figure it out later 2025 return 0; 2026 } 2027 } 2028} 2029 2030bool Sema::CheckArithmeticConstantExpression(const Expr* Init) { 2031 switch (Init->getStmtClass()) { 2032 default: 2033 InitializerElementNotConstant(Init); 2034 return true; 2035 case Expr::ParenExprClass: { 2036 const ParenExpr* PE = cast<ParenExpr>(Init); 2037 return CheckArithmeticConstantExpression(PE->getSubExpr()); 2038 } 2039 case Expr::FloatingLiteralClass: 2040 case Expr::IntegerLiteralClass: 2041 case Expr::CharacterLiteralClass: 2042 case Expr::ImaginaryLiteralClass: 2043 case Expr::TypesCompatibleExprClass: 2044 case Expr::CXXBoolLiteralExprClass: 2045 return false; 2046 case Expr::CallExprClass: 2047 case Expr::CXXOperatorCallExprClass: { 2048 const CallExpr *CE = cast<CallExpr>(Init); 2049 2050 // Allow any constant foldable calls to builtins. 2051 if (CE->isBuiltinCall() && CE->isEvaluatable(Context)) 2052 return false; 2053 2054 InitializerElementNotConstant(Init); 2055 return true; 2056 } 2057 case Expr::DeclRefExprClass: 2058 case Expr::QualifiedDeclRefExprClass: { 2059 const Decl *D = cast<DeclRefExpr>(Init)->getDecl(); 2060 if (isa<EnumConstantDecl>(D)) 2061 return false; 2062 InitializerElementNotConstant(Init); 2063 return true; 2064 } 2065 case Expr::CompoundLiteralExprClass: 2066 // Allow "(vector type){2,4}"; normal C constraints don't allow this, 2067 // but vectors are allowed to be magic. 2068 if (Init->getType()->isVectorType()) 2069 return false; 2070 InitializerElementNotConstant(Init); 2071 return true; 2072 case Expr::UnaryOperatorClass: { 2073 const UnaryOperator *Exp = cast<UnaryOperator>(Init); 2074 2075 switch (Exp->getOpcode()) { 2076 // Address, indirect, pre/post inc/dec, etc are not valid constant exprs. 2077 // See C99 6.6p3. 2078 default: 2079 InitializerElementNotConstant(Init); 2080 return true; 2081 case UnaryOperator::OffsetOf: 2082 if (Exp->getSubExpr()->getType()->isConstantSizeType()) 2083 return false; 2084 InitializerElementNotConstant(Init); 2085 return true; 2086 case UnaryOperator::Extension: 2087 case UnaryOperator::LNot: 2088 case UnaryOperator::Plus: 2089 case UnaryOperator::Minus: 2090 case UnaryOperator::Not: 2091 return CheckArithmeticConstantExpression(Exp->getSubExpr()); 2092 } 2093 } 2094 case Expr::SizeOfAlignOfExprClass: { 2095 const SizeOfAlignOfExpr *Exp = cast<SizeOfAlignOfExpr>(Init); 2096 // Special check for void types, which are allowed as an extension 2097 if (Exp->getTypeOfArgument()->isVoidType()) 2098 return false; 2099 // alignof always evaluates to a constant. 2100 // FIXME: is sizeof(int[3.0]) a constant expression? 2101 if (Exp->isSizeOf() && !Exp->getTypeOfArgument()->isConstantSizeType()) { 2102 InitializerElementNotConstant(Init); 2103 return true; 2104 } 2105 return false; 2106 } 2107 case Expr::BinaryOperatorClass: { 2108 const BinaryOperator *Exp = cast<BinaryOperator>(Init); 2109 2110 if (Exp->getLHS()->getType()->isArithmeticType() && 2111 Exp->getRHS()->getType()->isArithmeticType()) { 2112 return CheckArithmeticConstantExpression(Exp->getLHS()) || 2113 CheckArithmeticConstantExpression(Exp->getRHS()); 2114 } 2115 2116 if (Exp->getLHS()->getType()->isPointerType() && 2117 Exp->getRHS()->getType()->isPointerType()) { 2118 const Expr* LHSBase = FindExpressionBaseAddress(Exp->getLHS()); 2119 const Expr* RHSBase = FindExpressionBaseAddress(Exp->getRHS()); 2120 2121 // Only allow a null (constant integer) base; we could 2122 // allow some additional cases if necessary, but this 2123 // is sufficient to cover offsetof-like constructs. 2124 if (!LHSBase && !RHSBase) { 2125 return CheckAddressConstantExpression(Exp->getLHS()) || 2126 CheckAddressConstantExpression(Exp->getRHS()); 2127 } 2128 } 2129 2130 InitializerElementNotConstant(Init); 2131 return true; 2132 } 2133 case Expr::ImplicitCastExprClass: 2134 case Expr::CStyleCastExprClass: { 2135 const Expr *SubExpr = cast<CastExpr>(Init)->getSubExpr(); 2136 if (SubExpr->getType()->isArithmeticType()) 2137 return CheckArithmeticConstantExpression(SubExpr); 2138 2139 if (SubExpr->getType()->isPointerType()) { 2140 const Expr* Base = FindExpressionBaseAddress(SubExpr); 2141 // If the pointer has a null base, this is an offsetof-like construct 2142 if (!Base) 2143 return CheckAddressConstantExpression(SubExpr); 2144 } 2145 2146 InitializerElementNotConstant(Init); 2147 return true; 2148 } 2149 case Expr::ConditionalOperatorClass: { 2150 const ConditionalOperator *Exp = cast<ConditionalOperator>(Init); 2151 2152 // If GNU extensions are disabled, we require all operands to be arithmetic 2153 // constant expressions. 2154 if (getLangOptions().NoExtensions) { 2155 return CheckArithmeticConstantExpression(Exp->getCond()) || 2156 (Exp->getLHS() && CheckArithmeticConstantExpression(Exp->getLHS())) || 2157 CheckArithmeticConstantExpression(Exp->getRHS()); 2158 } 2159 2160 // Otherwise, we have to emulate some of the behavior of fold here. 2161 // Basically GCC treats things like "4 ? 1 : somefunc()" as a constant 2162 // because it can constant fold things away. To retain compatibility with 2163 // GCC code, we see if we can fold the condition to a constant (which we 2164 // should always be able to do in theory). If so, we only require the 2165 // specified arm of the conditional to be a constant. This is a horrible 2166 // hack, but is require by real world code that uses __builtin_constant_p. 2167 Expr::EvalResult EvalResult; 2168 if (!Exp->getCond()->Evaluate(EvalResult, Context) || 2169 EvalResult.HasSideEffects) { 2170 // If Evaluate couldn't fold it, CheckArithmeticConstantExpression 2171 // won't be able to either. Use it to emit the diagnostic though. 2172 bool Res = CheckArithmeticConstantExpression(Exp->getCond()); 2173 assert(Res && "Evaluate couldn't evaluate this constant?"); 2174 return Res; 2175 } 2176 2177 // Verify that the side following the condition is also a constant. 2178 const Expr *TrueSide = Exp->getLHS(), *FalseSide = Exp->getRHS(); 2179 if (EvalResult.Val.getInt() == 0) 2180 std::swap(TrueSide, FalseSide); 2181 2182 if (TrueSide && CheckArithmeticConstantExpression(TrueSide)) 2183 return true; 2184 2185 // Okay, the evaluated side evaluates to a constant, so we accept this. 2186 // Check to see if the other side is obviously not a constant. If so, 2187 // emit a warning that this is a GNU extension. 2188 if (FalseSide && !FalseSide->isEvaluatable(Context)) 2189 Diag(Init->getExprLoc(), 2190 diag::ext_typecheck_expression_not_constant_but_accepted) 2191 << FalseSide->getSourceRange(); 2192 return false; 2193 } 2194 } 2195} 2196 2197bool Sema::CheckForConstantInitializer(Expr *Init, QualType DclT) { 2198 Expr::EvalResult Result; 2199 2200 Init = Init->IgnoreParens(); 2201 2202 if (Init->Evaluate(Result, Context) && !Result.HasSideEffects) 2203 return false; 2204 2205 // Look through CXXDefaultArgExprs; they have no meaning in this context. 2206 if (CXXDefaultArgExpr* DAE = dyn_cast<CXXDefaultArgExpr>(Init)) 2207 return CheckForConstantInitializer(DAE->getExpr(), DclT); 2208 2209 if (CompoundLiteralExpr *e = dyn_cast<CompoundLiteralExpr>(Init)) 2210 return CheckForConstantInitializer(e->getInitializer(), DclT); 2211 2212 if (InitListExpr *Exp = dyn_cast<InitListExpr>(Init)) { 2213 unsigned numInits = Exp->getNumInits(); 2214 for (unsigned i = 0; i < numInits; i++) { 2215 // FIXME: Need to get the type of the declaration for C++, 2216 // because it could be a reference? 2217 if (CheckForConstantInitializer(Exp->getInit(i), 2218 Exp->getInit(i)->getType())) 2219 return true; 2220 } 2221 return false; 2222 } 2223 2224 // FIXME: We can probably remove some of this code below, now that 2225 // Expr::Evaluate is doing the heavy lifting for scalars. 2226 2227 if (Init->isNullPointerConstant(Context)) 2228 return false; 2229 if (Init->getType()->isArithmeticType()) { 2230 QualType InitTy = Context.getCanonicalType(Init->getType()) 2231 .getUnqualifiedType(); 2232 if (InitTy == Context.BoolTy) { 2233 // Special handling for pointers implicitly cast to bool; 2234 // (e.g. "_Bool rr = &rr;"). This is only legal at the top level. 2235 if (ImplicitCastExpr* ICE = dyn_cast<ImplicitCastExpr>(Init)) { 2236 Expr* SubE = ICE->getSubExpr(); 2237 if (SubE->getType()->isPointerType() || 2238 SubE->getType()->isArrayType() || 2239 SubE->getType()->isFunctionType()) { 2240 return CheckAddressConstantExpression(Init); 2241 } 2242 } 2243 } else if (InitTy->isIntegralType()) { 2244 Expr* SubE = 0; 2245 if (CastExpr* CE = dyn_cast<CastExpr>(Init)) 2246 SubE = CE->getSubExpr(); 2247 // Special check for pointer cast to int; we allow as an extension 2248 // an address constant cast to an integer if the integer 2249 // is of an appropriate width (this sort of code is apparently used 2250 // in some places). 2251 // FIXME: Add pedwarn? 2252 // FIXME: Don't allow bitfields here! Need the FieldDecl for that. 2253 if (SubE && (SubE->getType()->isPointerType() || 2254 SubE->getType()->isArrayType() || 2255 SubE->getType()->isFunctionType())) { 2256 unsigned IntWidth = Context.getTypeSize(Init->getType()); 2257 unsigned PointerWidth = Context.getTypeSize(Context.VoidPtrTy); 2258 if (IntWidth >= PointerWidth) 2259 return CheckAddressConstantExpression(Init); 2260 } 2261 } 2262 2263 return CheckArithmeticConstantExpression(Init); 2264 } 2265 2266 if (Init->getType()->isPointerType()) 2267 return CheckAddressConstantExpression(Init); 2268 2269 // An array type at the top level that isn't an init-list must 2270 // be a string literal 2271 if (Init->getType()->isArrayType()) 2272 return false; 2273 2274 if (Init->getType()->isFunctionType()) 2275 return false; 2276 2277 // Allow block exprs at top level. 2278 if (Init->getType()->isBlockPointerType()) 2279 return false; 2280 2281 InitializerElementNotConstant(Init); 2282 return true; 2283} 2284 2285void Sema::AddInitializerToDecl(DeclTy *dcl, ExprArg init) { 2286 Decl *RealDecl = static_cast<Decl *>(dcl); 2287 Expr *Init = static_cast<Expr *>(init.release()); 2288 assert(Init && "missing initializer"); 2289 2290 // If there is no declaration, there was an error parsing it. Just ignore 2291 // the initializer. 2292 if (RealDecl == 0) { 2293 delete Init; 2294 return; 2295 } 2296 2297 VarDecl *VDecl = dyn_cast<VarDecl>(RealDecl); 2298 if (!VDecl) { 2299 Diag(dyn_cast<ScopedDecl>(RealDecl)->getLocation(), 2300 diag::err_illegal_initializer); 2301 RealDecl->setInvalidDecl(); 2302 return; 2303 } 2304 // Get the decls type and save a reference for later, since 2305 // CheckInitializerTypes may change it. 2306 QualType DclT = VDecl->getType(), SavT = DclT; 2307 if (VDecl->isBlockVarDecl()) { 2308 VarDecl::StorageClass SC = VDecl->getStorageClass(); 2309 if (SC == VarDecl::Extern) { // C99 6.7.8p5 2310 Diag(VDecl->getLocation(), diag::err_block_extern_cant_init); 2311 VDecl->setInvalidDecl(); 2312 } else if (!VDecl->isInvalidDecl()) { 2313 if (CheckInitializerTypes(Init, DclT, VDecl->getLocation(), 2314 VDecl->getDeclName())) 2315 VDecl->setInvalidDecl(); 2316 2317 // C++ 3.6.2p2, allow dynamic initialization of static initializers. 2318 if (!getLangOptions().CPlusPlus) { 2319 if (SC == VarDecl::Static) // C99 6.7.8p4. 2320 CheckForConstantInitializer(Init, DclT); 2321 } 2322 } 2323 } else if (VDecl->isFileVarDecl()) { 2324 if (VDecl->getStorageClass() == VarDecl::Extern) 2325 Diag(VDecl->getLocation(), diag::warn_extern_init); 2326 if (!VDecl->isInvalidDecl()) 2327 if (CheckInitializerTypes(Init, DclT, VDecl->getLocation(), 2328 VDecl->getDeclName())) 2329 VDecl->setInvalidDecl(); 2330 2331 // C++ 3.6.2p2, allow dynamic initialization of static initializers. 2332 if (!getLangOptions().CPlusPlus) { 2333 // C99 6.7.8p4. All file scoped initializers need to be constant. 2334 CheckForConstantInitializer(Init, DclT); 2335 } 2336 } 2337 // If the type changed, it means we had an incomplete type that was 2338 // completed by the initializer. For example: 2339 // int ary[] = { 1, 3, 5 }; 2340 // "ary" transitions from a VariableArrayType to a ConstantArrayType. 2341 if (!VDecl->isInvalidDecl() && (DclT != SavT)) { 2342 VDecl->setType(DclT); 2343 Init->setType(DclT); 2344 } 2345 2346 // Attach the initializer to the decl. 2347 VDecl->setInit(Init); 2348 return; 2349} 2350 2351void Sema::ActOnUninitializedDecl(DeclTy *dcl) { 2352 Decl *RealDecl = static_cast<Decl *>(dcl); 2353 2354 // If there is no declaration, there was an error parsing it. Just ignore it. 2355 if (RealDecl == 0) 2356 return; 2357 2358 if (VarDecl *Var = dyn_cast<VarDecl>(RealDecl)) { 2359 QualType Type = Var->getType(); 2360 // C++ [dcl.init.ref]p3: 2361 // The initializer can be omitted for a reference only in a 2362 // parameter declaration (8.3.5), in the declaration of a 2363 // function return type, in the declaration of a class member 2364 // within its class declaration (9.2), and where the extern 2365 // specifier is explicitly used. 2366 if (Type->isReferenceType() && 2367 Var->getStorageClass() != VarDecl::Extern && 2368 Var->getStorageClass() != VarDecl::PrivateExtern) { 2369 Diag(Var->getLocation(), diag::err_reference_var_requires_init) 2370 << Var->getDeclName() 2371 << SourceRange(Var->getLocation(), Var->getLocation()); 2372 Var->setInvalidDecl(); 2373 return; 2374 } 2375 2376 // C++ [dcl.init]p9: 2377 // 2378 // If no initializer is specified for an object, and the object 2379 // is of (possibly cv-qualified) non-POD class type (or array 2380 // thereof), the object shall be default-initialized; if the 2381 // object is of const-qualified type, the underlying class type 2382 // shall have a user-declared default constructor. 2383 if (getLangOptions().CPlusPlus) { 2384 QualType InitType = Type; 2385 if (const ArrayType *Array = Context.getAsArrayType(Type)) 2386 InitType = Array->getElementType(); 2387 if (Var->getStorageClass() != VarDecl::Extern && 2388 Var->getStorageClass() != VarDecl::PrivateExtern && 2389 InitType->isRecordType()) { 2390 const CXXConstructorDecl *Constructor 2391 = PerformInitializationByConstructor(InitType, 0, 0, 2392 Var->getLocation(), 2393 SourceRange(Var->getLocation(), 2394 Var->getLocation()), 2395 Var->getDeclName(), 2396 IK_Default); 2397 if (!Constructor) 2398 Var->setInvalidDecl(); 2399 } 2400 } 2401 2402#if 0 2403 // FIXME: Temporarily disabled because we are not properly parsing 2404 // linkage specifications on declarations, e.g., 2405 // 2406 // extern "C" const CGPoint CGPointerZero; 2407 // 2408 // C++ [dcl.init]p9: 2409 // 2410 // If no initializer is specified for an object, and the 2411 // object is of (possibly cv-qualified) non-POD class type (or 2412 // array thereof), the object shall be default-initialized; if 2413 // the object is of const-qualified type, the underlying class 2414 // type shall have a user-declared default 2415 // constructor. Otherwise, if no initializer is specified for 2416 // an object, the object and its subobjects, if any, have an 2417 // indeterminate initial value; if the object or any of its 2418 // subobjects are of const-qualified type, the program is 2419 // ill-formed. 2420 // 2421 // This isn't technically an error in C, so we don't diagnose it. 2422 // 2423 // FIXME: Actually perform the POD/user-defined default 2424 // constructor check. 2425 if (getLangOptions().CPlusPlus && 2426 Context.getCanonicalType(Type).isConstQualified() && 2427 Var->getStorageClass() != VarDecl::Extern) 2428 Diag(Var->getLocation(), diag::err_const_var_requires_init) 2429 << Var->getName() 2430 << SourceRange(Var->getLocation(), Var->getLocation()); 2431#endif 2432 } 2433} 2434 2435/// The declarators are chained together backwards, reverse the list. 2436Sema::DeclTy *Sema::FinalizeDeclaratorGroup(Scope *S, DeclTy *group) { 2437 // Often we have single declarators, handle them quickly. 2438 Decl *GroupDecl = static_cast<Decl*>(group); 2439 if (GroupDecl == 0) 2440 return 0; 2441 2442 ScopedDecl *Group = dyn_cast<ScopedDecl>(GroupDecl); 2443 ScopedDecl *NewGroup = 0; 2444 if (Group->getNextDeclarator() == 0) 2445 NewGroup = Group; 2446 else { // reverse the list. 2447 while (Group) { 2448 ScopedDecl *Next = Group->getNextDeclarator(); 2449 Group->setNextDeclarator(NewGroup); 2450 NewGroup = Group; 2451 Group = Next; 2452 } 2453 } 2454 // Perform semantic analysis that depends on having fully processed both 2455 // the declarator and initializer. 2456 for (ScopedDecl *ID = NewGroup; ID; ID = ID->getNextDeclarator()) { 2457 VarDecl *IDecl = dyn_cast<VarDecl>(ID); 2458 if (!IDecl) 2459 continue; 2460 QualType T = IDecl->getType(); 2461 2462 if (T->isVariableArrayType()) { 2463 const VariableArrayType *VAT = Context.getAsVariableArrayType(T); 2464 2465 // FIXME: This won't give the correct result for 2466 // int a[10][n]; 2467 SourceRange SizeRange = VAT->getSizeExpr()->getSourceRange(); 2468 if (IDecl->isFileVarDecl()) { 2469 Diag(IDecl->getLocation(), diag::err_vla_decl_in_file_scope) << 2470 SizeRange; 2471 2472 IDecl->setInvalidDecl(); 2473 } else { 2474 // C99 6.7.5.2p2: If an identifier is declared to be an object with 2475 // static storage duration, it shall not have a variable length array. 2476 if (IDecl->getStorageClass() == VarDecl::Static) { 2477 Diag(IDecl->getLocation(), diag::err_vla_decl_has_static_storage) 2478 << SizeRange; 2479 IDecl->setInvalidDecl(); 2480 } else if (IDecl->getStorageClass() == VarDecl::Extern) { 2481 Diag(IDecl->getLocation(), diag::err_vla_decl_has_extern_linkage) 2482 << SizeRange; 2483 IDecl->setInvalidDecl(); 2484 } 2485 } 2486 } else if (T->isVariablyModifiedType()) { 2487 if (IDecl->isFileVarDecl()) { 2488 Diag(IDecl->getLocation(), diag::err_vm_decl_in_file_scope); 2489 IDecl->setInvalidDecl(); 2490 } else { 2491 if (IDecl->getStorageClass() == VarDecl::Extern) { 2492 Diag(IDecl->getLocation(), diag::err_vm_decl_has_extern_linkage); 2493 IDecl->setInvalidDecl(); 2494 } 2495 } 2496 } 2497 2498 // Block scope. C99 6.7p7: If an identifier for an object is declared with 2499 // no linkage (C99 6.2.2p6), the type for the object shall be complete... 2500 if (IDecl->isBlockVarDecl() && 2501 IDecl->getStorageClass() != VarDecl::Extern) { 2502 if (T->isIncompleteType() && !IDecl->isInvalidDecl()) { 2503 Diag(IDecl->getLocation(), diag::err_typecheck_decl_incomplete_type)<<T; 2504 IDecl->setInvalidDecl(); 2505 } 2506 } 2507 // File scope. C99 6.9.2p2: A declaration of an identifier for and 2508 // object that has file scope without an initializer, and without a 2509 // storage-class specifier or with the storage-class specifier "static", 2510 // constitutes a tentative definition. Note: A tentative definition with 2511 // external linkage is valid (C99 6.2.2p5). 2512 if (isTentativeDefinition(IDecl)) { 2513 if (T->isIncompleteArrayType()) { 2514 // C99 6.9.2 (p2, p5): Implicit initialization causes an incomplete 2515 // array to be completed. Don't issue a diagnostic. 2516 } else if (T->isIncompleteType() && !IDecl->isInvalidDecl()) { 2517 // C99 6.9.2p3: If the declaration of an identifier for an object is 2518 // a tentative definition and has internal linkage (C99 6.2.2p3), the 2519 // declared type shall not be an incomplete type. 2520 Diag(IDecl->getLocation(), diag::err_typecheck_decl_incomplete_type)<<T; 2521 IDecl->setInvalidDecl(); 2522 } 2523 } 2524 if (IDecl->isFileVarDecl()) 2525 CheckForFileScopedRedefinitions(S, IDecl); 2526 } 2527 return NewGroup; 2528} 2529 2530/// ActOnParamDeclarator - Called from Parser::ParseFunctionDeclarator() 2531/// to introduce parameters into function prototype scope. 2532Sema::DeclTy * 2533Sema::ActOnParamDeclarator(Scope *S, Declarator &D) { 2534 const DeclSpec &DS = D.getDeclSpec(); 2535 2536 // Verify C99 6.7.5.3p2: The only SCS allowed is 'register'. 2537 VarDecl::StorageClass StorageClass = VarDecl::None; 2538 if (DS.getStorageClassSpec() == DeclSpec::SCS_register) { 2539 StorageClass = VarDecl::Register; 2540 } else if (DS.getStorageClassSpec() != DeclSpec::SCS_unspecified) { 2541 Diag(DS.getStorageClassSpecLoc(), 2542 diag::err_invalid_storage_class_in_func_decl); 2543 D.getMutableDeclSpec().ClearStorageClassSpecs(); 2544 } 2545 if (DS.isThreadSpecified()) { 2546 Diag(DS.getThreadSpecLoc(), 2547 diag::err_invalid_storage_class_in_func_decl); 2548 D.getMutableDeclSpec().ClearStorageClassSpecs(); 2549 } 2550 2551 // Check that there are no default arguments inside the type of this 2552 // parameter (C++ only). 2553 if (getLangOptions().CPlusPlus) 2554 CheckExtraCXXDefaultArguments(D); 2555 2556 // In this context, we *do not* check D.getInvalidType(). If the declarator 2557 // type was invalid, GetTypeForDeclarator() still returns a "valid" type, 2558 // though it will not reflect the user specified type. 2559 QualType parmDeclType = GetTypeForDeclarator(D, S); 2560 2561 assert(!parmDeclType.isNull() && "GetTypeForDeclarator() returned null type"); 2562 2563 // TODO: CHECK FOR CONFLICTS, multiple decls with same name in one scope. 2564 // Can this happen for params? We already checked that they don't conflict 2565 // among each other. Here they can only shadow globals, which is ok. 2566 IdentifierInfo *II = D.getIdentifier(); 2567 if (Decl *PrevDecl = LookupDecl(II, Decl::IDNS_Ordinary, S)) { 2568 if (PrevDecl->isTemplateParameter()) { 2569 // Maybe we will complain about the shadowed template parameter. 2570 DiagnoseTemplateParameterShadow(D.getIdentifierLoc(), PrevDecl); 2571 // Just pretend that we didn't see the previous declaration. 2572 PrevDecl = 0; 2573 } else if (S->isDeclScope(PrevDecl)) { 2574 Diag(D.getIdentifierLoc(), diag::err_param_redefinition) << II; 2575 2576 // Recover by removing the name 2577 II = 0; 2578 D.SetIdentifier(0, D.getIdentifierLoc()); 2579 } 2580 } 2581 2582 // Perform the default function/array conversion (C99 6.7.5.3p[7,8]). 2583 // Doing the promotion here has a win and a loss. The win is the type for 2584 // both Decl's and DeclRefExpr's will match (a convenient invariant for the 2585 // code generator). The loss is the orginal type isn't preserved. For example: 2586 // 2587 // void func(int parmvardecl[5]) { // convert "int [5]" to "int *" 2588 // int blockvardecl[5]; 2589 // sizeof(parmvardecl); // size == 4 2590 // sizeof(blockvardecl); // size == 20 2591 // } 2592 // 2593 // For expressions, all implicit conversions are captured using the 2594 // ImplicitCastExpr AST node (we have no such mechanism for Decl's). 2595 // 2596 // FIXME: If a source translation tool needs to see the original type, then 2597 // we need to consider storing both types (in ParmVarDecl)... 2598 // 2599 if (parmDeclType->isArrayType()) { 2600 // int x[restrict 4] -> int *restrict 2601 parmDeclType = Context.getArrayDecayedType(parmDeclType); 2602 } else if (parmDeclType->isFunctionType()) 2603 parmDeclType = Context.getPointerType(parmDeclType); 2604 2605 ParmVarDecl *New = ParmVarDecl::Create(Context, CurContext, 2606 D.getIdentifierLoc(), II, 2607 parmDeclType, StorageClass, 2608 0, 0); 2609 2610 if (D.getInvalidType()) 2611 New->setInvalidDecl(); 2612 2613 // Parameter declarators cannot be qualified (C++ [dcl.meaning]p1). 2614 if (D.getCXXScopeSpec().isSet()) { 2615 Diag(D.getIdentifierLoc(), diag::err_qualified_param_declarator) 2616 << D.getCXXScopeSpec().getRange(); 2617 New->setInvalidDecl(); 2618 } 2619 2620 // Add the parameter declaration into this scope. 2621 S->AddDecl(New); 2622 if (II) 2623 IdResolver.AddDecl(New); 2624 2625 ProcessDeclAttributes(New, D); 2626 return New; 2627 2628} 2629 2630Sema::DeclTy *Sema::ActOnStartOfFunctionDef(Scope *FnBodyScope, Declarator &D) { 2631 assert(getCurFunctionDecl() == 0 && "Function parsing confused"); 2632 assert(D.getTypeObject(0).Kind == DeclaratorChunk::Function && 2633 "Not a function declarator!"); 2634 DeclaratorChunk::FunctionTypeInfo &FTI = D.getTypeObject(0).Fun; 2635 2636 // Verify 6.9.1p6: 'every identifier in the identifier list shall be declared' 2637 // for a K&R function. 2638 if (!FTI.hasPrototype) { 2639 for (unsigned i = 0, e = FTI.NumArgs; i != e; ++i) { 2640 if (FTI.ArgInfo[i].Param == 0) { 2641 Diag(FTI.ArgInfo[i].IdentLoc, diag::ext_param_not_declared) 2642 << FTI.ArgInfo[i].Ident; 2643 // Implicitly declare the argument as type 'int' for lack of a better 2644 // type. 2645 DeclSpec DS; 2646 const char* PrevSpec; // unused 2647 DS.SetTypeSpecType(DeclSpec::TST_int, FTI.ArgInfo[i].IdentLoc, 2648 PrevSpec); 2649 Declarator ParamD(DS, Declarator::KNRTypeListContext); 2650 ParamD.SetIdentifier(FTI.ArgInfo[i].Ident, FTI.ArgInfo[i].IdentLoc); 2651 FTI.ArgInfo[i].Param = ActOnParamDeclarator(FnBodyScope, ParamD); 2652 } 2653 } 2654 } else { 2655 // FIXME: Diagnose arguments without names in C. 2656 } 2657 2658 Scope *ParentScope = FnBodyScope->getParent(); 2659 2660 return ActOnStartOfFunctionDef(FnBodyScope, 2661 ActOnDeclarator(ParentScope, D, 0, 2662 /*IsFunctionDefinition=*/true)); 2663} 2664 2665Sema::DeclTy *Sema::ActOnStartOfFunctionDef(Scope *FnBodyScope, DeclTy *D) { 2666 Decl *decl = static_cast<Decl*>(D); 2667 FunctionDecl *FD = cast<FunctionDecl>(decl); 2668 2669 // See if this is a redefinition. 2670 const FunctionDecl *Definition; 2671 if (FD->getBody(Definition)) { 2672 Diag(FD->getLocation(), diag::err_redefinition) << FD->getDeclName(); 2673 Diag(Definition->getLocation(), diag::note_previous_definition); 2674 } 2675 2676 PushDeclContext(FnBodyScope, FD); 2677 2678 // Check the validity of our function parameters 2679 CheckParmsForFunctionDef(FD); 2680 2681 // Introduce our parameters into the function scope 2682 for (unsigned p = 0, NumParams = FD->getNumParams(); p < NumParams; ++p) { 2683 ParmVarDecl *Param = FD->getParamDecl(p); 2684 // If this has an identifier, add it to the scope stack. 2685 if (Param->getIdentifier()) 2686 PushOnScopeChains(Param, FnBodyScope); 2687 } 2688 2689 // Checking attributes of current function definition 2690 // dllimport attribute. 2691 if (FD->getAttr<DLLImportAttr>() && (!FD->getAttr<DLLExportAttr>())) { 2692 // dllimport attribute cannot be applied to definition. 2693 if (!(FD->getAttr<DLLImportAttr>())->isInherited()) { 2694 Diag(FD->getLocation(), 2695 diag::err_attribute_can_be_applied_only_to_symbol_declaration) 2696 << "dllimport"; 2697 FD->setInvalidDecl(); 2698 return FD; 2699 } else { 2700 // If a symbol previously declared dllimport is later defined, the 2701 // attribute is ignored in subsequent references, and a warning is 2702 // emitted. 2703 Diag(FD->getLocation(), 2704 diag::warn_redeclaration_without_attribute_prev_attribute_ignored) 2705 << FD->getNameAsCString() << "dllimport"; 2706 } 2707 } 2708 return FD; 2709} 2710 2711Sema::DeclTy *Sema::ActOnFinishFunctionBody(DeclTy *D, StmtArg BodyArg) { 2712 Decl *dcl = static_cast<Decl *>(D); 2713 Stmt *Body = static_cast<Stmt*>(BodyArg.release()); 2714 if (FunctionDecl *FD = dyn_cast_or_null<FunctionDecl>(dcl)) { 2715 FD->setBody(Body); 2716 assert(FD == getCurFunctionDecl() && "Function parsing confused"); 2717 } else if (ObjCMethodDecl *MD = dyn_cast_or_null<ObjCMethodDecl>(dcl)) { 2718 MD->setBody((Stmt*)Body); 2719 } else 2720 return 0; 2721 PopDeclContext(); 2722 // Verify and clean out per-function state. 2723 2724 // Check goto/label use. 2725 for (llvm::DenseMap<IdentifierInfo*, LabelStmt*>::iterator 2726 I = LabelMap.begin(), E = LabelMap.end(); I != E; ++I) { 2727 // Verify that we have no forward references left. If so, there was a goto 2728 // or address of a label taken, but no definition of it. Label fwd 2729 // definitions are indicated with a null substmt. 2730 if (I->second->getSubStmt() == 0) { 2731 LabelStmt *L = I->second; 2732 // Emit error. 2733 Diag(L->getIdentLoc(), diag::err_undeclared_label_use) << L->getName(); 2734 2735 // At this point, we have gotos that use the bogus label. Stitch it into 2736 // the function body so that they aren't leaked and that the AST is well 2737 // formed. 2738 if (Body) { 2739 L->setSubStmt(new NullStmt(L->getIdentLoc())); 2740 cast<CompoundStmt>(Body)->push_back(L); 2741 } else { 2742 // The whole function wasn't parsed correctly, just delete this. 2743 delete L; 2744 } 2745 } 2746 } 2747 LabelMap.clear(); 2748 2749 return D; 2750} 2751 2752/// ImplicitlyDefineFunction - An undeclared identifier was used in a function 2753/// call, forming a call to an implicitly defined function (per C99 6.5.1p2). 2754ScopedDecl *Sema::ImplicitlyDefineFunction(SourceLocation Loc, 2755 IdentifierInfo &II, Scope *S) { 2756 // Extension in C99. Legal in C90, but warn about it. 2757 if (getLangOptions().C99) 2758 Diag(Loc, diag::ext_implicit_function_decl) << &II; 2759 else 2760 Diag(Loc, diag::warn_implicit_function_decl) << &II; 2761 2762 // FIXME: handle stuff like: 2763 // void foo() { extern float X(); } 2764 // void bar() { X(); } <-- implicit decl for X in another scope. 2765 2766 // Set a Declarator for the implicit definition: int foo(); 2767 const char *Dummy; 2768 DeclSpec DS; 2769 bool Error = DS.SetTypeSpecType(DeclSpec::TST_int, Loc, Dummy); 2770 Error = Error; // Silence warning. 2771 assert(!Error && "Error setting up implicit decl!"); 2772 Declarator D(DS, Declarator::BlockContext); 2773 D.AddTypeInfo(DeclaratorChunk::getFunction(false, false, 0, 0, 0, Loc)); 2774 D.SetIdentifier(&II, Loc); 2775 2776 // Insert this function into translation-unit scope. 2777 2778 DeclContext *PrevDC = CurContext; 2779 CurContext = Context.getTranslationUnitDecl(); 2780 2781 FunctionDecl *FD = 2782 dyn_cast<FunctionDecl>(static_cast<Decl*>(ActOnDeclarator(TUScope, D, 0))); 2783 FD->setImplicit(); 2784 2785 CurContext = PrevDC; 2786 2787 return FD; 2788} 2789 2790 2791TypedefDecl *Sema::ParseTypedefDecl(Scope *S, Declarator &D, QualType T, 2792 ScopedDecl *LastDeclarator) { 2793 assert(D.getIdentifier() && "Wrong callback for declspec without declarator"); 2794 assert(!T.isNull() && "GetTypeForDeclarator() returned null type"); 2795 2796 // Scope manipulation handled by caller. 2797 TypedefDecl *NewTD = TypedefDecl::Create(Context, CurContext, 2798 D.getIdentifierLoc(), 2799 D.getIdentifier(), 2800 T, LastDeclarator); 2801 if (D.getInvalidType()) 2802 NewTD->setInvalidDecl(); 2803 return NewTD; 2804} 2805 2806/// ActOnTag - This is invoked when we see 'struct foo' or 'struct {'. In the 2807/// former case, Name will be non-null. In the later case, Name will be null. 2808/// TagType indicates what kind of tag this is. TK indicates whether this is a 2809/// reference/declaration/definition of a tag. 2810Sema::DeclTy *Sema::ActOnTag(Scope *S, unsigned TagType, TagKind TK, 2811 SourceLocation KWLoc, const CXXScopeSpec &SS, 2812 IdentifierInfo *Name, SourceLocation NameLoc, 2813 AttributeList *Attr, 2814 MultiTemplateParamsArg TemplateParameterLists) { 2815 // If this is not a definition, it must have a name. 2816 assert((Name != 0 || TK == TK_Definition) && 2817 "Nameless record must be a definition!"); 2818 2819 TagDecl::TagKind Kind; 2820 switch (TagType) { 2821 default: assert(0 && "Unknown tag type!"); 2822 case DeclSpec::TST_struct: Kind = TagDecl::TK_struct; break; 2823 case DeclSpec::TST_union: Kind = TagDecl::TK_union; break; 2824 case DeclSpec::TST_class: Kind = TagDecl::TK_class; break; 2825 case DeclSpec::TST_enum: Kind = TagDecl::TK_enum; break; 2826 } 2827 2828 DeclContext *DC = CurContext; 2829 ScopedDecl *PrevDecl = 0; 2830 2831 if (Name && SS.isNotEmpty()) { 2832 // We have a nested-name tag ('struct foo::bar'). 2833 2834 // Check for invalid 'foo::'. 2835 if (SS.isInvalid()) { 2836 Name = 0; 2837 goto CreateNewDecl; 2838 } 2839 2840 DC = static_cast<DeclContext*>(SS.getScopeRep()); 2841 // Look-up name inside 'foo::'. 2842 PrevDecl = dyn_cast_or_null<TagDecl>(LookupDecl(Name, Decl::IDNS_Tag,S,DC)); 2843 2844 // A tag 'foo::bar' must already exist. 2845 if (PrevDecl == 0) { 2846 Diag(NameLoc, diag::err_not_tag_in_scope) << Name << SS.getRange(); 2847 Name = 0; 2848 goto CreateNewDecl; 2849 } 2850 } else { 2851 // If this is a named struct, check to see if there was a previous forward 2852 // declaration or definition. 2853 // Use ScopedDecl instead of TagDecl, because a NamespaceDecl may come up. 2854 PrevDecl = dyn_cast_or_null<ScopedDecl>(LookupDecl(Name, Decl::IDNS_Tag,S)); 2855 } 2856 2857 if (PrevDecl && PrevDecl->isTemplateParameter()) { 2858 // Maybe we will complain about the shadowed template parameter. 2859 DiagnoseTemplateParameterShadow(NameLoc, PrevDecl); 2860 // Just pretend that we didn't see the previous declaration. 2861 PrevDecl = 0; 2862 } 2863 2864 if (PrevDecl) { 2865 assert((isa<TagDecl>(PrevDecl) || isa<NamespaceDecl>(PrevDecl)) && 2866 "unexpected Decl type"); 2867 if (TagDecl *PrevTagDecl = dyn_cast<TagDecl>(PrevDecl)) { 2868 // If this is a use of a previous tag, or if the tag is already declared 2869 // in the same scope (so that the definition/declaration completes or 2870 // rementions the tag), reuse the decl. 2871 if (TK == TK_Reference || isDeclInScope(PrevDecl, DC, S)) { 2872 // Make sure that this wasn't declared as an enum and now used as a 2873 // struct or something similar. 2874 if (PrevTagDecl->getTagKind() != Kind) { 2875 Diag(KWLoc, diag::err_use_with_wrong_tag) << Name; 2876 Diag(PrevDecl->getLocation(), diag::note_previous_use); 2877 // Recover by making this an anonymous redefinition. 2878 Name = 0; 2879 PrevDecl = 0; 2880 } else { 2881 // If this is a use, just return the declaration we found. 2882 2883 // FIXME: In the future, return a variant or some other clue 2884 // for the consumer of this Decl to know it doesn't own it. 2885 // For our current ASTs this shouldn't be a problem, but will 2886 // need to be changed with DeclGroups. 2887 if (TK == TK_Reference) 2888 return PrevDecl; 2889 2890 // Diagnose attempts to redefine a tag. 2891 if (TK == TK_Definition) { 2892 if (TagDecl *Def = PrevTagDecl->getDefinition(Context)) { 2893 Diag(NameLoc, diag::err_redefinition) << Name; 2894 Diag(Def->getLocation(), diag::note_previous_definition); 2895 // If this is a redefinition, recover by making this struct be 2896 // anonymous, which will make any later references get the previous 2897 // definition. 2898 Name = 0; 2899 PrevDecl = 0; 2900 } 2901 // Okay, this is definition of a previously declared or referenced 2902 // tag PrevDecl. We're going to create a new Decl for it. 2903 } 2904 } 2905 // If we get here we have (another) forward declaration or we 2906 // have a definition. Just create a new decl. 2907 } else { 2908 // If we get here, this is a definition of a new tag type in a nested 2909 // scope, e.g. "struct foo; void bar() { struct foo; }", just create a 2910 // new decl/type. We set PrevDecl to NULL so that the entities 2911 // have distinct types. 2912 PrevDecl = 0; 2913 } 2914 // If we get here, we're going to create a new Decl. If PrevDecl 2915 // is non-NULL, it's a definition of the tag declared by 2916 // PrevDecl. If it's NULL, we have a new definition. 2917 } else { 2918 // PrevDecl is a namespace. 2919 if (isDeclInScope(PrevDecl, DC, S)) { 2920 // The tag name clashes with a namespace name, issue an error and 2921 // recover by making this tag be anonymous. 2922 Diag(NameLoc, diag::err_redefinition_different_kind) << Name; 2923 Diag(PrevDecl->getLocation(), diag::note_previous_definition); 2924 Name = 0; 2925 PrevDecl = 0; 2926 } else { 2927 // The existing declaration isn't relevant to us; we're in a 2928 // new scope, so clear out the previous declaration. 2929 PrevDecl = 0; 2930 } 2931 } 2932 } 2933 2934CreateNewDecl: 2935 2936 // If there is an identifier, use the location of the identifier as the 2937 // location of the decl, otherwise use the location of the struct/union 2938 // keyword. 2939 SourceLocation Loc = NameLoc.isValid() ? NameLoc : KWLoc; 2940 2941 // Otherwise, create a new declaration. If there is a previous 2942 // declaration of the same entity, the two will be linked via 2943 // PrevDecl. 2944 TagDecl *New; 2945 2946 if (Kind == TagDecl::TK_enum) { 2947 // FIXME: Tag decls should be chained to any simultaneous vardecls, e.g.: 2948 // enum X { A, B, C } D; D should chain to X. 2949 New = EnumDecl::Create(Context, DC, Loc, Name, 2950 cast_or_null<EnumDecl>(PrevDecl)); 2951 // If this is an undefined enum, warn. 2952 if (TK != TK_Definition) Diag(Loc, diag::ext_forward_ref_enum); 2953 } else { 2954 // struct/union/class 2955 2956 // FIXME: Tag decls should be chained to any simultaneous vardecls, e.g.: 2957 // struct X { int A; } D; D should chain to X. 2958 if (getLangOptions().CPlusPlus) 2959 // FIXME: Look for a way to use RecordDecl for simple structs. 2960 New = CXXRecordDecl::Create(Context, Kind, DC, Loc, Name, 2961 cast_or_null<CXXRecordDecl>(PrevDecl)); 2962 else 2963 New = RecordDecl::Create(Context, Kind, DC, Loc, Name, 2964 cast_or_null<RecordDecl>(PrevDecl)); 2965 } 2966 2967 if (Kind != TagDecl::TK_enum) { 2968 // Handle #pragma pack: if the #pragma pack stack has non-default 2969 // alignment, make up a packed attribute for this decl. These 2970 // attributes are checked when the ASTContext lays out the 2971 // structure. 2972 // 2973 // It is important for implementing the correct semantics that this 2974 // happen here (in act on tag decl). The #pragma pack stack is 2975 // maintained as a result of parser callbacks which can occur at 2976 // many points during the parsing of a struct declaration (because 2977 // the #pragma tokens are effectively skipped over during the 2978 // parsing of the struct). 2979 if (unsigned Alignment = PackContext.getAlignment()) 2980 New->addAttr(new PackedAttr(Alignment * 8)); 2981 } 2982 2983 if (Attr) 2984 ProcessDeclAttributeList(New, Attr); 2985 2986 // Set the lexical context. If the tag has a C++ scope specifier, the 2987 // lexical context will be different from the semantic context. 2988 New->setLexicalDeclContext(CurContext); 2989 2990 // If this has an identifier, add it to the scope stack. 2991 if (Name) { 2992 // The scope passed in may not be a decl scope. Zip up the scope tree until 2993 // we find one that is. 2994 while ((S->getFlags() & Scope::DeclScope) == 0) 2995 S = S->getParent(); 2996 2997 // Add it to the decl chain. 2998 PushOnScopeChains(New, S); 2999 } else if (getLangOptions().CPlusPlus) { 3000 // FIXME: We also want to do this for C, but if this tag is 3001 // defined within a structure CurContext will point to the context 3002 // enclosing the structure, and we would end up inserting the tag 3003 // type into the wrong place. 3004 CurContext->addDecl(Context, New); 3005 } 3006 3007 return New; 3008} 3009 3010 3011/// TryToFixInvalidVariablyModifiedType - Helper method to turn variable array 3012/// types into constant array types in certain situations which would otherwise 3013/// be errors (for GCC compatibility). 3014static QualType TryToFixInvalidVariablyModifiedType(QualType T, 3015 ASTContext &Context) { 3016 // This method tries to turn a variable array into a constant 3017 // array even when the size isn't an ICE. This is necessary 3018 // for compatibility with code that depends on gcc's buggy 3019 // constant expression folding, like struct {char x[(int)(char*)2];} 3020 const VariableArrayType* VLATy = dyn_cast<VariableArrayType>(T); 3021 if (!VLATy) return QualType(); 3022 3023 Expr::EvalResult EvalResult; 3024 if (!VLATy->getSizeExpr() || 3025 !VLATy->getSizeExpr()->Evaluate(EvalResult, Context)) 3026 return QualType(); 3027 3028 assert(EvalResult.Val.isInt() && "Size expressions must be integers!"); 3029 llvm::APSInt &Res = EvalResult.Val.getInt(); 3030 if (Res > llvm::APSInt(Res.getBitWidth(), Res.isUnsigned())) 3031 return Context.getConstantArrayType(VLATy->getElementType(), 3032 Res, ArrayType::Normal, 0); 3033 return QualType(); 3034} 3035 3036bool Sema::VerifyBitField(SourceLocation FieldLoc, IdentifierInfo *FieldName, 3037 QualType FieldTy, const Expr *BitWidth) { 3038 // FIXME: 6.7.2.1p4 - verify the field type. 3039 3040 llvm::APSInt Value; 3041 if (VerifyIntegerConstantExpression(BitWidth, &Value)) 3042 return true; 3043 3044 // Zero-width bitfield is ok for anonymous field. 3045 if (Value == 0 && FieldName) 3046 return Diag(FieldLoc, diag::err_bitfield_has_zero_width) << FieldName; 3047 3048 if (Value.isNegative()) 3049 return Diag(FieldLoc, diag::err_bitfield_has_negative_width) << FieldName; 3050 3051 uint64_t TypeSize = Context.getTypeSize(FieldTy); 3052 // FIXME: We won't need the 0 size once we check that the field type is valid. 3053 if (TypeSize && Value.getZExtValue() > TypeSize) 3054 return Diag(FieldLoc, diag::err_bitfield_width_exceeds_type_size) 3055 << FieldName << (unsigned)TypeSize; 3056 3057 return false; 3058} 3059 3060/// ActOnField - Each field of a struct/union/class is passed into this in order 3061/// to create a FieldDecl object for it. 3062Sema::DeclTy *Sema::ActOnField(Scope *S, DeclTy *TagD, 3063 SourceLocation DeclStart, 3064 Declarator &D, ExprTy *BitfieldWidth) { 3065 IdentifierInfo *II = D.getIdentifier(); 3066 Expr *BitWidth = (Expr*)BitfieldWidth; 3067 SourceLocation Loc = DeclStart; 3068 RecordDecl *Record = (RecordDecl *)TagD; 3069 if (II) Loc = D.getIdentifierLoc(); 3070 3071 // FIXME: Unnamed fields can be handled in various different ways, for 3072 // example, unnamed unions inject all members into the struct namespace! 3073 3074 QualType T = GetTypeForDeclarator(D, S); 3075 assert(!T.isNull() && "GetTypeForDeclarator() returned null type"); 3076 bool InvalidDecl = false; 3077 3078 // C99 6.7.2.1p8: A member of a structure or union may have any type other 3079 // than a variably modified type. 3080 if (T->isVariablyModifiedType()) { 3081 QualType FixedTy = TryToFixInvalidVariablyModifiedType(T, Context); 3082 if (!FixedTy.isNull()) { 3083 Diag(Loc, diag::warn_illegal_constant_array_size); 3084 T = FixedTy; 3085 } else { 3086 Diag(Loc, diag::err_typecheck_field_variable_size); 3087 T = Context.IntTy; 3088 InvalidDecl = true; 3089 } 3090 } 3091 3092 if (BitWidth) { 3093 if (VerifyBitField(Loc, II, T, BitWidth)) 3094 InvalidDecl = true; 3095 } else { 3096 // Not a bitfield. 3097 3098 // validate II. 3099 3100 } 3101 3102 // FIXME: Chain fielddecls together. 3103 FieldDecl *NewFD; 3104 3105 NewFD = FieldDecl::Create(Context, Record, 3106 Loc, II, T, BitWidth, 3107 D.getDeclSpec().getStorageClassSpec() == 3108 DeclSpec::SCS_mutable, 3109 /*PrevDecl=*/0); 3110 3111 if (getLangOptions().CPlusPlus) { 3112 CheckExtraCXXDefaultArguments(D); 3113 if (!T->isPODType()) 3114 cast<CXXRecordDecl>(Record)->setPOD(false); 3115 } 3116 3117 ProcessDeclAttributes(NewFD, D); 3118 3119 if (D.getInvalidType() || InvalidDecl) 3120 NewFD->setInvalidDecl(); 3121 3122 if (II && getLangOptions().CPlusPlus) 3123 PushOnScopeChains(NewFD, S); 3124 else 3125 Record->addDecl(Context, NewFD); 3126 3127 return NewFD; 3128} 3129 3130/// TranslateIvarVisibility - Translate visibility from a token ID to an 3131/// AST enum value. 3132static ObjCIvarDecl::AccessControl 3133TranslateIvarVisibility(tok::ObjCKeywordKind ivarVisibility) { 3134 switch (ivarVisibility) { 3135 default: assert(0 && "Unknown visitibility kind"); 3136 case tok::objc_private: return ObjCIvarDecl::Private; 3137 case tok::objc_public: return ObjCIvarDecl::Public; 3138 case tok::objc_protected: return ObjCIvarDecl::Protected; 3139 case tok::objc_package: return ObjCIvarDecl::Package; 3140 } 3141} 3142 3143/// ActOnIvar - Each ivar field of an objective-c class is passed into this 3144/// in order to create an IvarDecl object for it. 3145Sema::DeclTy *Sema::ActOnIvar(Scope *S, 3146 SourceLocation DeclStart, 3147 Declarator &D, ExprTy *BitfieldWidth, 3148 tok::ObjCKeywordKind Visibility) { 3149 IdentifierInfo *II = D.getIdentifier(); 3150 Expr *BitWidth = (Expr*)BitfieldWidth; 3151 SourceLocation Loc = DeclStart; 3152 if (II) Loc = D.getIdentifierLoc(); 3153 3154 // FIXME: Unnamed fields can be handled in various different ways, for 3155 // example, unnamed unions inject all members into the struct namespace! 3156 3157 QualType T = GetTypeForDeclarator(D, S); 3158 assert(!T.isNull() && "GetTypeForDeclarator() returned null type"); 3159 bool InvalidDecl = false; 3160 3161 if (BitWidth) { 3162 // TODO: Validate. 3163 //printf("WARNING: BITFIELDS IGNORED!\n"); 3164 3165 // 6.7.2.1p3 3166 // 6.7.2.1p4 3167 3168 } else { 3169 // Not a bitfield. 3170 3171 // validate II. 3172 3173 } 3174 3175 // C99 6.7.2.1p8: A member of a structure or union may have any type other 3176 // than a variably modified type. 3177 if (T->isVariablyModifiedType()) { 3178 Diag(Loc, diag::err_typecheck_ivar_variable_size); 3179 InvalidDecl = true; 3180 } 3181 3182 // Get the visibility (access control) for this ivar. 3183 ObjCIvarDecl::AccessControl ac = 3184 Visibility != tok::objc_not_keyword ? TranslateIvarVisibility(Visibility) 3185 : ObjCIvarDecl::None; 3186 3187 // Construct the decl. 3188 ObjCIvarDecl *NewID = ObjCIvarDecl::Create(Context, Loc, II, T, ac, 3189 (Expr *)BitfieldWidth); 3190 3191 // Process attributes attached to the ivar. 3192 ProcessDeclAttributes(NewID, D); 3193 3194 if (D.getInvalidType() || InvalidDecl) 3195 NewID->setInvalidDecl(); 3196 3197 return NewID; 3198} 3199 3200void Sema::ActOnFields(Scope* S, 3201 SourceLocation RecLoc, DeclTy *RecDecl, 3202 DeclTy **Fields, unsigned NumFields, 3203 SourceLocation LBrac, SourceLocation RBrac, 3204 AttributeList *Attr) { 3205 Decl *EnclosingDecl = static_cast<Decl*>(RecDecl); 3206 assert(EnclosingDecl && "missing record or interface decl"); 3207 RecordDecl *Record = dyn_cast<RecordDecl>(EnclosingDecl); 3208 3209 if (Record) 3210 if (RecordDecl* DefRecord = Record->getDefinition(Context)) { 3211 // Diagnose code like: 3212 // struct S { struct S {} X; }; 3213 // We discover this when we complete the outer S. Reject and ignore the 3214 // outer S. 3215 Diag(DefRecord->getLocation(), diag::err_nested_redefinition) 3216 << DefRecord->getDeclName(); 3217 Diag(RecLoc, diag::note_previous_definition); 3218 Record->setInvalidDecl(); 3219 return; 3220 } 3221 3222 // Verify that all the fields are okay. 3223 unsigned NumNamedMembers = 0; 3224 llvm::SmallVector<FieldDecl*, 32> RecFields; 3225 3226 // FIXME: Eventually, we'd like to eliminate this in favor of 3227 // checking for redeclarations on-the-fly. 3228 llvm::DenseMap<const IdentifierInfo*, FieldDecl *> FieldIDs; 3229 3230 for (unsigned i = 0; i != NumFields; ++i) { 3231 FieldDecl *FD = cast_or_null<FieldDecl>(static_cast<Decl*>(Fields[i])); 3232 assert(FD && "missing field decl"); 3233 3234 // Get the type for the field. 3235 Type *FDTy = FD->getType().getTypePtr(); 3236 3237 if (FD->isAnonymousStructOrUnion()) { 3238 // We have found a field that represents an anonymous struct 3239 // or union. Introduce all of the inner fields (recursively) 3240 // into the list of fields we know about, so that we can produce 3241 // an appropriate error message in cases like: 3242 // 3243 // struct X { 3244 // union { 3245 // int x; 3246 // float f; 3247 // }; 3248 // double x; 3249 // }; 3250 llvm::SmallVector<FieldDecl *, 4> AnonStructUnionFields; 3251 AnonStructUnionFields.push_back(FD); 3252 while (!AnonStructUnionFields.empty()) { 3253 FieldDecl *AnonField = AnonStructUnionFields.back(); 3254 AnonStructUnionFields.pop_back(); 3255 3256 RecordDecl *AnonRecord 3257 = AnonField->getType()->getAsRecordType()->getDecl(); 3258 for (RecordDecl::field_iterator F = AnonRecord->field_begin(), 3259 FEnd = AnonRecord->field_end(); 3260 F != FEnd; ++F) { 3261 if ((*F)->isAnonymousStructOrUnion()) 3262 AnonStructUnionFields.push_back(*F); 3263 else if (const IdentifierInfo *II = (*F)->getIdentifier()) 3264 FieldIDs[II] = *F; 3265 } 3266 } 3267 } else { 3268 // Remember all fields written by the user. 3269 RecFields.push_back(FD); 3270 } 3271 3272 // C99 6.7.2.1p2 - A field may not be a function type. 3273 if (FDTy->isFunctionType()) { 3274 Diag(FD->getLocation(), diag::err_field_declared_as_function) 3275 << FD->getDeclName(); 3276 FD->setInvalidDecl(); 3277 EnclosingDecl->setInvalidDecl(); 3278 continue; 3279 } 3280 // C99 6.7.2.1p2 - A field may not be an incomplete type except... 3281 if (FDTy->isIncompleteType()) { 3282 if (!Record) { // Incomplete ivar type is always an error. 3283 Diag(FD->getLocation(), diag::err_field_incomplete) <<FD->getDeclName(); 3284 FD->setInvalidDecl(); 3285 EnclosingDecl->setInvalidDecl(); 3286 continue; 3287 } 3288 if (i != NumFields-1 || // ... that the last member ... 3289 !Record->isStruct() || // ... of a structure ... 3290 !FDTy->isArrayType()) { //... may have incomplete array type. 3291 Diag(FD->getLocation(), diag::err_field_incomplete) <<FD->getDeclName(); 3292 FD->setInvalidDecl(); 3293 EnclosingDecl->setInvalidDecl(); 3294 continue; 3295 } 3296 if (NumNamedMembers < 1) { //... must have more than named member ... 3297 Diag(FD->getLocation(), diag::err_flexible_array_empty_struct) 3298 << FD->getDeclName(); 3299 FD->setInvalidDecl(); 3300 EnclosingDecl->setInvalidDecl(); 3301 continue; 3302 } 3303 // Okay, we have a legal flexible array member at the end of the struct. 3304 if (Record) 3305 Record->setHasFlexibleArrayMember(true); 3306 } 3307 /// C99 6.7.2.1p2 - a struct ending in a flexible array member cannot be the 3308 /// field of another structure or the element of an array. 3309 if (const RecordType *FDTTy = FDTy->getAsRecordType()) { 3310 if (FDTTy->getDecl()->hasFlexibleArrayMember()) { 3311 // If this is a member of a union, then entire union becomes "flexible". 3312 if (Record && Record->isUnion()) { 3313 Record->setHasFlexibleArrayMember(true); 3314 } else { 3315 // If this is a struct/class and this is not the last element, reject 3316 // it. Note that GCC supports variable sized arrays in the middle of 3317 // structures. 3318 if (i != NumFields-1) { 3319 Diag(FD->getLocation(), diag::err_variable_sized_type_in_struct) 3320 << FD->getDeclName(); 3321 FD->setInvalidDecl(); 3322 EnclosingDecl->setInvalidDecl(); 3323 continue; 3324 } 3325 // We support flexible arrays at the end of structs in other structs 3326 // as an extension. 3327 Diag(FD->getLocation(), diag::ext_flexible_array_in_struct) 3328 << FD->getDeclName(); 3329 if (Record) 3330 Record->setHasFlexibleArrayMember(true); 3331 } 3332 } 3333 } 3334 /// A field cannot be an Objective-c object 3335 if (FDTy->isObjCInterfaceType()) { 3336 Diag(FD->getLocation(), diag::err_statically_allocated_object) 3337 << FD->getDeclName(); 3338 FD->setInvalidDecl(); 3339 EnclosingDecl->setInvalidDecl(); 3340 continue; 3341 } 3342 // Keep track of the number of named members. 3343 if (IdentifierInfo *II = FD->getIdentifier()) { 3344 // Detect duplicate member names. 3345 if (FieldIDs[II]) { 3346 Diag(FD->getLocation(), diag::err_duplicate_member) << II; 3347 // Find the previous decl. 3348 Diag(FieldIDs[II]->getLocation(), diag::note_previous_definition); 3349 FD->setInvalidDecl(); 3350 EnclosingDecl->setInvalidDecl(); 3351 continue; 3352 } 3353 ++NumNamedMembers; 3354 FieldIDs[II] = FD; 3355 } 3356 } 3357 3358 // Okay, we successfully defined 'Record'. 3359 if (Record) { 3360 Record->completeDefinition(Context); 3361 // If this is a C++ record, HandleTagDeclDefinition will be invoked in 3362 // Sema::ActOnFinishCXXClassDef. 3363 if (!isa<CXXRecordDecl>(Record)) 3364 Consumer.HandleTagDeclDefinition(Record); 3365 } else { 3366 ObjCIvarDecl **ClsFields = reinterpret_cast<ObjCIvarDecl**>(&RecFields[0]); 3367 if (ObjCInterfaceDecl *ID = dyn_cast<ObjCInterfaceDecl>(EnclosingDecl)) { 3368 ID->addInstanceVariablesToClass(ClsFields, RecFields.size(), RBrac); 3369 // Must enforce the rule that ivars in the base classes may not be 3370 // duplicates. 3371 if (ID->getSuperClass()) { 3372 for (ObjCInterfaceDecl::ivar_iterator IVI = ID->ivar_begin(), 3373 IVE = ID->ivar_end(); IVI != IVE; ++IVI) { 3374 ObjCIvarDecl* Ivar = (*IVI); 3375 IdentifierInfo *II = Ivar->getIdentifier(); 3376 ObjCIvarDecl* prevIvar = ID->getSuperClass()->FindIvarDeclaration(II); 3377 if (prevIvar) { 3378 Diag(Ivar->getLocation(), diag::err_duplicate_member) << II; 3379 Diag(prevIvar->getLocation(), diag::note_previous_definition); 3380 } 3381 } 3382 } 3383 } 3384 else if (ObjCImplementationDecl *IMPDecl = 3385 dyn_cast<ObjCImplementationDecl>(EnclosingDecl)) { 3386 assert(IMPDecl && "ActOnFields - missing ObjCImplementationDecl"); 3387 IMPDecl->ObjCAddInstanceVariablesToClassImpl(ClsFields, RecFields.size()); 3388 CheckImplementationIvars(IMPDecl, ClsFields, RecFields.size(), RBrac); 3389 } 3390 } 3391 3392 if (Attr) 3393 ProcessDeclAttributeList(Record, Attr); 3394} 3395 3396void Sema::ActOnEnumStartDefinition(Scope *S, DeclTy *EnumD) { 3397 EnumDecl *Enum = cast<EnumDecl>((Decl *)EnumD); 3398 3399 // Enter the enumeration context. 3400 PushDeclContext(S, Enum); 3401} 3402 3403Sema::DeclTy *Sema::ActOnEnumConstant(Scope *S, DeclTy *theEnumDecl, 3404 DeclTy *lastEnumConst, 3405 SourceLocation IdLoc, IdentifierInfo *Id, 3406 SourceLocation EqualLoc, ExprTy *val) { 3407 EnumDecl *TheEnumDecl = cast<EnumDecl>(static_cast<Decl*>(theEnumDecl)); 3408 EnumConstantDecl *LastEnumConst = 3409 cast_or_null<EnumConstantDecl>(static_cast<Decl*>(lastEnumConst)); 3410 Expr *Val = static_cast<Expr*>(val); 3411 3412 // The scope passed in may not be a decl scope. Zip up the scope tree until 3413 // we find one that is. 3414 while ((S->getFlags() & Scope::DeclScope) == 0) 3415 S = S->getParent(); 3416 3417 // Verify that there isn't already something declared with this name in this 3418 // scope. 3419 Decl *PrevDecl = LookupDecl(Id, Decl::IDNS_Ordinary, S); 3420 if (PrevDecl && PrevDecl->isTemplateParameter()) { 3421 // Maybe we will complain about the shadowed template parameter. 3422 DiagnoseTemplateParameterShadow(IdLoc, PrevDecl); 3423 // Just pretend that we didn't see the previous declaration. 3424 PrevDecl = 0; 3425 } 3426 3427 if (PrevDecl) { 3428 // When in C++, we may get a TagDecl with the same name; in this case the 3429 // enum constant will 'hide' the tag. 3430 assert((getLangOptions().CPlusPlus || !isa<TagDecl>(PrevDecl)) && 3431 "Received TagDecl when not in C++!"); 3432 if (!isa<TagDecl>(PrevDecl) && isDeclInScope(PrevDecl, CurContext, S)) { 3433 if (isa<EnumConstantDecl>(PrevDecl)) 3434 Diag(IdLoc, diag::err_redefinition_of_enumerator) << Id; 3435 else 3436 Diag(IdLoc, diag::err_redefinition) << Id; 3437 Diag(PrevDecl->getLocation(), diag::note_previous_definition); 3438 delete Val; 3439 return 0; 3440 } 3441 } 3442 3443 llvm::APSInt EnumVal(32); 3444 QualType EltTy; 3445 if (Val) { 3446 // Make sure to promote the operand type to int. 3447 UsualUnaryConversions(Val); 3448 3449 // C99 6.7.2.2p2: Make sure we have an integer constant expression. 3450 SourceLocation ExpLoc; 3451 if (VerifyIntegerConstantExpression(Val, &EnumVal)) { 3452 delete Val; 3453 Val = 0; // Just forget about it. 3454 } else { 3455 EltTy = Val->getType(); 3456 } 3457 } 3458 3459 if (!Val) { 3460 if (LastEnumConst) { 3461 // Assign the last value + 1. 3462 EnumVal = LastEnumConst->getInitVal(); 3463 ++EnumVal; 3464 3465 // Check for overflow on increment. 3466 if (EnumVal < LastEnumConst->getInitVal()) 3467 Diag(IdLoc, diag::warn_enum_value_overflow); 3468 3469 EltTy = LastEnumConst->getType(); 3470 } else { 3471 // First value, set to zero. 3472 EltTy = Context.IntTy; 3473 EnumVal.zextOrTrunc(static_cast<uint32_t>(Context.getTypeSize(EltTy))); 3474 } 3475 } 3476 3477 EnumConstantDecl *New = 3478 EnumConstantDecl::Create(Context, TheEnumDecl, IdLoc, Id, EltTy, 3479 Val, EnumVal, 3480 LastEnumConst); 3481 3482 // Register this decl in the current scope stack. 3483 PushOnScopeChains(New, S); 3484 3485 // Add this enumerator into the enum itself. 3486 // FIXME: This means that the enumerator is stored in two 3487 // DeclContexts. This is not a long-term solution. 3488 New->setLexicalDeclContext(TheEnumDecl); 3489 TheEnumDecl->addDecl(Context, New, true); 3490 return New; 3491} 3492 3493// FIXME: For consistency with ActOnFields(), we should have the parser 3494// pass in the source location for the left/right braces. 3495void Sema::ActOnEnumBody(SourceLocation EnumLoc, DeclTy *EnumDeclX, 3496 DeclTy **Elements, unsigned NumElements) { 3497 EnumDecl *Enum = cast<EnumDecl>(static_cast<Decl*>(EnumDeclX)); 3498 QualType EnumType = Context.getTypeDeclType(Enum); 3499 3500 if (EnumType->getAsEnumType()->getDecl()->isDefinition()) { 3501 EnumDecl *Def = EnumType->getAsEnumType()->getDecl(); 3502 // Diagnose code like: 3503 // enum e0 { 3504 // E0 = sizeof(enum e0 { E1 }) 3505 // }; 3506 Diag(Def->getLocation(), diag::err_nested_redefinition) 3507 << Enum->getDeclName(); 3508 Diag(Enum->getLocation(), diag::note_previous_definition); 3509 Enum->setInvalidDecl(); 3510 PopDeclContext(); 3511 return; 3512 } 3513 3514 // TODO: If the result value doesn't fit in an int, it must be a long or long 3515 // long value. ISO C does not support this, but GCC does as an extension, 3516 // emit a warning. 3517 unsigned IntWidth = Context.Target.getIntWidth(); 3518 3519 // Verify that all the values are okay, compute the size of the values, and 3520 // reverse the list. 3521 unsigned NumNegativeBits = 0; 3522 unsigned NumPositiveBits = 0; 3523 3524 // Keep track of whether all elements have type int. 3525 bool AllElementsInt = true; 3526 3527 EnumConstantDecl *EltList = 0; 3528 for (unsigned i = 0; i != NumElements; ++i) { 3529 EnumConstantDecl *ECD = 3530 cast_or_null<EnumConstantDecl>(static_cast<Decl*>(Elements[i])); 3531 if (!ECD) continue; // Already issued a diagnostic. 3532 3533 // If the enum value doesn't fit in an int, emit an extension warning. 3534 const llvm::APSInt &InitVal = ECD->getInitVal(); 3535 assert(InitVal.getBitWidth() >= IntWidth && 3536 "Should have promoted value to int"); 3537 if (InitVal.getBitWidth() > IntWidth) { 3538 llvm::APSInt V(InitVal); 3539 V.trunc(IntWidth); 3540 V.extend(InitVal.getBitWidth()); 3541 if (V != InitVal) 3542 Diag(ECD->getLocation(), diag::ext_enum_value_not_int) 3543 << InitVal.toString(10); 3544 } 3545 3546 // Keep track of the size of positive and negative values. 3547 if (InitVal.isUnsigned() || InitVal.isNonNegative()) 3548 NumPositiveBits = std::max(NumPositiveBits, 3549 (unsigned)InitVal.getActiveBits()); 3550 else 3551 NumNegativeBits = std::max(NumNegativeBits, 3552 (unsigned)InitVal.getMinSignedBits()); 3553 3554 // Keep track of whether every enum element has type int (very commmon). 3555 if (AllElementsInt) 3556 AllElementsInt = ECD->getType() == Context.IntTy; 3557 3558 ECD->setNextDeclarator(EltList); 3559 EltList = ECD; 3560 } 3561 3562 // Figure out the type that should be used for this enum. 3563 // FIXME: Support attribute(packed) on enums and -fshort-enums. 3564 QualType BestType; 3565 unsigned BestWidth; 3566 3567 if (NumNegativeBits) { 3568 // If there is a negative value, figure out the smallest integer type (of 3569 // int/long/longlong) that fits. 3570 if (NumNegativeBits <= IntWidth && NumPositiveBits < IntWidth) { 3571 BestType = Context.IntTy; 3572 BestWidth = IntWidth; 3573 } else { 3574 BestWidth = Context.Target.getLongWidth(); 3575 3576 if (NumNegativeBits <= BestWidth && NumPositiveBits < BestWidth) 3577 BestType = Context.LongTy; 3578 else { 3579 BestWidth = Context.Target.getLongLongWidth(); 3580 3581 if (NumNegativeBits > BestWidth || NumPositiveBits >= BestWidth) 3582 Diag(Enum->getLocation(), diag::warn_enum_too_large); 3583 BestType = Context.LongLongTy; 3584 } 3585 } 3586 } else { 3587 // If there is no negative value, figure out which of uint, ulong, ulonglong 3588 // fits. 3589 if (NumPositiveBits <= IntWidth) { 3590 BestType = Context.UnsignedIntTy; 3591 BestWidth = IntWidth; 3592 } else if (NumPositiveBits <= 3593 (BestWidth = Context.Target.getLongWidth())) { 3594 BestType = Context.UnsignedLongTy; 3595 } else { 3596 BestWidth = Context.Target.getLongLongWidth(); 3597 assert(NumPositiveBits <= BestWidth && 3598 "How could an initializer get larger than ULL?"); 3599 BestType = Context.UnsignedLongLongTy; 3600 } 3601 } 3602 3603 // Loop over all of the enumerator constants, changing their types to match 3604 // the type of the enum if needed. 3605 for (unsigned i = 0; i != NumElements; ++i) { 3606 EnumConstantDecl *ECD = 3607 cast_or_null<EnumConstantDecl>(static_cast<Decl*>(Elements[i])); 3608 if (!ECD) continue; // Already issued a diagnostic. 3609 3610 // Standard C says the enumerators have int type, but we allow, as an 3611 // extension, the enumerators to be larger than int size. If each 3612 // enumerator value fits in an int, type it as an int, otherwise type it the 3613 // same as the enumerator decl itself. This means that in "enum { X = 1U }" 3614 // that X has type 'int', not 'unsigned'. 3615 if (ECD->getType() == Context.IntTy) { 3616 // Make sure the init value is signed. 3617 llvm::APSInt IV = ECD->getInitVal(); 3618 IV.setIsSigned(true); 3619 ECD->setInitVal(IV); 3620 3621 if (getLangOptions().CPlusPlus) 3622 // C++ [dcl.enum]p4: Following the closing brace of an 3623 // enum-specifier, each enumerator has the type of its 3624 // enumeration. 3625 ECD->setType(EnumType); 3626 continue; // Already int type. 3627 } 3628 3629 // Determine whether the value fits into an int. 3630 llvm::APSInt InitVal = ECD->getInitVal(); 3631 bool FitsInInt; 3632 if (InitVal.isUnsigned() || !InitVal.isNegative()) 3633 FitsInInt = InitVal.getActiveBits() < IntWidth; 3634 else 3635 FitsInInt = InitVal.getMinSignedBits() <= IntWidth; 3636 3637 // If it fits into an integer type, force it. Otherwise force it to match 3638 // the enum decl type. 3639 QualType NewTy; 3640 unsigned NewWidth; 3641 bool NewSign; 3642 if (FitsInInt) { 3643 NewTy = Context.IntTy; 3644 NewWidth = IntWidth; 3645 NewSign = true; 3646 } else if (ECD->getType() == BestType) { 3647 // Already the right type! 3648 if (getLangOptions().CPlusPlus) 3649 // C++ [dcl.enum]p4: Following the closing brace of an 3650 // enum-specifier, each enumerator has the type of its 3651 // enumeration. 3652 ECD->setType(EnumType); 3653 continue; 3654 } else { 3655 NewTy = BestType; 3656 NewWidth = BestWidth; 3657 NewSign = BestType->isSignedIntegerType(); 3658 } 3659 3660 // Adjust the APSInt value. 3661 InitVal.extOrTrunc(NewWidth); 3662 InitVal.setIsSigned(NewSign); 3663 ECD->setInitVal(InitVal); 3664 3665 // Adjust the Expr initializer and type. 3666 ECD->setInitExpr(new ImplicitCastExpr(NewTy, ECD->getInitExpr(), 3667 /*isLvalue=*/false)); 3668 if (getLangOptions().CPlusPlus) 3669 // C++ [dcl.enum]p4: Following the closing brace of an 3670 // enum-specifier, each enumerator has the type of its 3671 // enumeration. 3672 ECD->setType(EnumType); 3673 else 3674 ECD->setType(NewTy); 3675 } 3676 3677 Enum->completeDefinition(Context, BestType); 3678 Consumer.HandleTagDeclDefinition(Enum); 3679 3680 // Leave the context of the enumeration. 3681 PopDeclContext(); 3682} 3683 3684Sema::DeclTy *Sema::ActOnFileScopeAsmDecl(SourceLocation Loc, 3685 ExprArg expr) { 3686 StringLiteral *AsmString = cast<StringLiteral>((Expr*)expr.release()); 3687 3688 return FileScopeAsmDecl::Create(Context, Loc, AsmString); 3689} 3690 3691 3692void Sema::ActOnPragmaPack(PragmaPackKind Kind, IdentifierInfo *Name, 3693 ExprTy *alignment, SourceLocation PragmaLoc, 3694 SourceLocation LParenLoc, SourceLocation RParenLoc) { 3695 Expr *Alignment = static_cast<Expr *>(alignment); 3696 3697 // If specified then alignment must be a "small" power of two. 3698 unsigned AlignmentVal = 0; 3699 if (Alignment) { 3700 llvm::APSInt Val; 3701 if (!Alignment->isIntegerConstantExpr(Val, Context) || 3702 !Val.isPowerOf2() || 3703 Val.getZExtValue() > 16) { 3704 Diag(PragmaLoc, diag::warn_pragma_pack_invalid_alignment); 3705 delete Alignment; 3706 return; // Ignore 3707 } 3708 3709 AlignmentVal = (unsigned) Val.getZExtValue(); 3710 } 3711 3712 switch (Kind) { 3713 case Action::PPK_Default: // pack([n]) 3714 PackContext.setAlignment(AlignmentVal); 3715 break; 3716 3717 case Action::PPK_Show: // pack(show) 3718 // Show the current alignment, making sure to show the right value 3719 // for the default. 3720 AlignmentVal = PackContext.getAlignment(); 3721 // FIXME: This should come from the target. 3722 if (AlignmentVal == 0) 3723 AlignmentVal = 8; 3724 Diag(PragmaLoc, diag::warn_pragma_pack_show) << AlignmentVal; 3725 break; 3726 3727 case Action::PPK_Push: // pack(push [, id] [, [n]) 3728 PackContext.push(Name); 3729 // Set the new alignment if specified. 3730 if (Alignment) 3731 PackContext.setAlignment(AlignmentVal); 3732 break; 3733 3734 case Action::PPK_Pop: // pack(pop [, id] [, n]) 3735 // MSDN, C/C++ Preprocessor Reference > Pragma Directives > pack: 3736 // "#pragma pack(pop, identifier, n) is undefined" 3737 if (Alignment && Name) 3738 Diag(PragmaLoc, diag::warn_pragma_pack_pop_identifer_and_alignment); 3739 3740 // Do the pop. 3741 if (!PackContext.pop(Name)) { 3742 // If a name was specified then failure indicates the name 3743 // wasn't found. Otherwise failure indicates the stack was 3744 // empty. 3745 Diag(PragmaLoc, diag::warn_pragma_pack_pop_failed) 3746 << (Name ? "no record matching name" : "stack empty"); 3747 3748 // FIXME: Warn about popping named records as MSVC does. 3749 } else { 3750 // Pop succeeded, set the new alignment if specified. 3751 if (Alignment) 3752 PackContext.setAlignment(AlignmentVal); 3753 } 3754 break; 3755 3756 default: 3757 assert(0 && "Invalid #pragma pack kind."); 3758 } 3759} 3760 3761bool PragmaPackStack::pop(IdentifierInfo *Name) { 3762 if (Stack.empty()) 3763 return false; 3764 3765 // If name is empty just pop top. 3766 if (!Name) { 3767 Alignment = Stack.back().first; 3768 Stack.pop_back(); 3769 return true; 3770 } 3771 3772 // Otherwise, find the named record. 3773 for (unsigned i = Stack.size(); i != 0; ) { 3774 --i; 3775 if (Stack[i].second == Name) { 3776 // Found it, pop up to and including this record. 3777 Alignment = Stack[i].first; 3778 Stack.erase(Stack.begin() + i, Stack.end()); 3779 return true; 3780 } 3781 } 3782 3783 return false; 3784} 3785