SemaDecl.cpp revision b27a8700761e1c1f955fc5cc3663289179c9e4d2
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 S->AddDecl(D); 97 98 // Add scoped declarations into their context, so that they can be 99 // found later. Declarations without a context won't be inserted 100 // into any context. 101 if (ScopedDecl *SD = dyn_cast<ScopedDecl>(D)) 102 CurContext->addDecl(Context, SD); 103 104 // C++ [basic.scope]p4: 105 // -- exactly one declaration shall declare a class name or 106 // enumeration name that is not a typedef name and the other 107 // declarations shall all refer to the same object or 108 // enumerator, or all refer to functions and function templates; 109 // in this case the class name or enumeration name is hidden. 110 if (TagDecl *TD = dyn_cast<TagDecl>(D)) { 111 // We are pushing the name of a tag (enum or class). 112 if (CurContext == TD->getDeclContext()) { 113 // We're pushing the tag into the current context, which might 114 // require some reshuffling in the identifier resolver. 115 IdentifierResolver::iterator 116 I = IdResolver.begin(TD->getDeclName(), CurContext, 117 false/*LookInParentCtx*/), 118 IEnd = IdResolver.end(); 119 if (I != IEnd && isDeclInScope(*I, CurContext, S)) { 120 NamedDecl *PrevDecl = *I; 121 for (; I != IEnd && isDeclInScope(*I, CurContext, S); 122 PrevDecl = *I, ++I) { 123 if (TD->declarationReplaces(*I)) { 124 // This is a redeclaration. Remove it from the chain and 125 // break out, so that we'll add in the shadowed 126 // declaration. 127 S->RemoveDecl(*I); 128 if (PrevDecl == *I) { 129 IdResolver.RemoveDecl(*I); 130 IdResolver.AddDecl(TD); 131 return; 132 } else { 133 IdResolver.RemoveDecl(*I); 134 break; 135 } 136 } 137 } 138 139 // There is already a declaration with the same name in the same 140 // scope, which is not a tag declaration. It must be found 141 // before we find the new declaration, so insert the new 142 // declaration at the end of the chain. 143 IdResolver.AddShadowedDecl(TD, PrevDecl); 144 145 return; 146 } 147 } 148 } else if (getLangOptions().CPlusPlus && isa<FunctionDecl>(D)) { 149 // We are pushing the name of a function, which might be an 150 // overloaded name. 151 FunctionDecl *FD = cast<FunctionDecl>(D); 152 IdentifierResolver::iterator Redecl 153 = std::find_if(IdResolver.begin(FD->getDeclName(), CurContext, 154 false/*LookInParentCtx*/), 155 IdResolver.end(), 156 std::bind1st(std::mem_fun(&ScopedDecl::declarationReplaces), 157 FD)); 158 if (Redecl != IdResolver.end()) { 159 // There is already a declaration of a function on our 160 // IdResolver chain. Replace it with this declaration. 161 S->RemoveDecl(*Redecl); 162 IdResolver.RemoveDecl(*Redecl); 163 } 164 } 165 166 IdResolver.AddDecl(D); 167} 168 169void Sema::ActOnPopScope(SourceLocation Loc, Scope *S) { 170 if (S->decl_empty()) return; 171 assert((S->getFlags() & (Scope::DeclScope | Scope::TemplateParamScope)) && 172 "Scope shouldn't contain decls!"); 173 174 for (Scope::decl_iterator I = S->decl_begin(), E = S->decl_end(); 175 I != E; ++I) { 176 Decl *TmpD = static_cast<Decl*>(*I); 177 assert(TmpD && "This decl didn't get pushed??"); 178 179 assert(isa<NamedDecl>(TmpD) && "Decl isn't NamedDecl?"); 180 NamedDecl *D = cast<NamedDecl>(TmpD); 181 182 if (!D->getDeclName()) continue; 183 184 // Remove this name from our lexical scope. 185 IdResolver.RemoveDecl(D); 186 } 187} 188 189/// getObjCInterfaceDecl - Look up a for a class declaration in the scope. 190/// return 0 if one not found. 191ObjCInterfaceDecl *Sema::getObjCInterfaceDecl(IdentifierInfo *Id) { 192 // The third "scope" argument is 0 since we aren't enabling lazy built-in 193 // creation from this context. 194 Decl *IDecl = LookupDecl(Id, Decl::IDNS_Ordinary, 0, false); 195 196 return dyn_cast_or_null<ObjCInterfaceDecl>(IDecl); 197} 198 199/// MaybeConstructOverloadSet - Name lookup has determined that the 200/// elements in [I, IEnd) have the name that we are looking for, and 201/// *I is a match for the namespace. This routine returns an 202/// appropriate Decl for name lookup, which may either be *I or an 203/// OverloadeFunctionDecl that represents the overloaded functions in 204/// [I, IEnd). 205/// 206/// The existance of this routine is temporary; LookupDecl should 207/// probably be able to return multiple results, to deal with cases of 208/// ambiguity and overloaded functions without needing to create a 209/// Decl node. 210template<typename DeclIterator> 211static Decl * 212MaybeConstructOverloadSet(ASTContext &Context, 213 DeclIterator I, DeclIterator IEnd) { 214 assert(I != IEnd && "Iterator range cannot be empty"); 215 assert(!isa<OverloadedFunctionDecl>(*I) && 216 "Cannot have an overloaded function"); 217 218 if (isa<FunctionDecl>(*I)) { 219 // If we found a function, there might be more functions. If 220 // so, collect them into an overload set. 221 DeclIterator Last = I; 222 OverloadedFunctionDecl *Ovl = 0; 223 for (++Last; Last != IEnd && isa<FunctionDecl>(*Last); ++Last) { 224 if (!Ovl) { 225 // FIXME: We leak this overload set. Eventually, we want to 226 // stop building the declarations for these overload sets, so 227 // there will be nothing to leak. 228 Ovl = OverloadedFunctionDecl::Create(Context, 229 cast<ScopedDecl>(*I)->getDeclContext(), 230 (*I)->getDeclName()); 231 Ovl->addOverload(cast<FunctionDecl>(*I)); 232 } 233 Ovl->addOverload(cast<FunctionDecl>(*Last)); 234 } 235 236 // If we had more than one function, we built an overload 237 // set. Return it. 238 if (Ovl) 239 return Ovl; 240 } 241 242 return *I; 243} 244 245/// LookupDecl - Look up the inner-most declaration in the specified 246/// namespace. 247Decl *Sema::LookupDecl(DeclarationName Name, unsigned NSI, Scope *S, 248 const DeclContext *LookupCtx, 249 bool enableLazyBuiltinCreation, 250 bool LookInParent) { 251 if (!Name) return 0; 252 unsigned NS = NSI; 253 if (getLangOptions().CPlusPlus && (NS & Decl::IDNS_Ordinary)) 254 NS |= Decl::IDNS_Tag; 255 256 if (LookupCtx == 0 && 257 (!getLangOptions().CPlusPlus || (NS == Decl::IDNS_Label))) { 258 // Unqualified name lookup in C/Objective-C and name lookup for 259 // labels in C++ is purely lexical, so search in the 260 // declarations attached to the name. 261 assert(!LookupCtx && "Can't perform qualified name lookup here"); 262 IdentifierResolver::iterator I 263 = IdResolver.begin(Name, CurContext, LookInParent); 264 265 // Scan up the scope chain looking for a decl that matches this 266 // identifier that is in the appropriate namespace. This search 267 // should not take long, as shadowing of names is uncommon, and 268 // deep shadowing is extremely uncommon. 269 for (; I != IdResolver.end(); ++I) 270 if ((*I)->getIdentifierNamespace() & NS) 271 return *I; 272 } else if (LookupCtx) { 273 // Perform qualified name lookup into the LookupCtx. 274 // FIXME: Will need to look into base classes and such. 275 DeclContext::lookup_const_iterator I, E; 276 for (llvm::tie(I, E) = LookupCtx->lookup(Context, Name); I != E; ++I) 277 if ((*I)->getIdentifierNamespace() & NS) 278 return MaybeConstructOverloadSet(Context, I, E); 279 } else { 280 // Name lookup for ordinary names and tag names in C++ requires 281 // looking into scopes that aren't strictly lexical, and 282 // therefore we walk through the context as well as walking 283 // through the scopes. 284 IdentifierResolver::iterator 285 I = IdResolver.begin(Name, CurContext, true/*LookInParentCtx*/), 286 IEnd = IdResolver.end(); 287 for (; S; S = S->getParent()) { 288 // Check whether the IdResolver has anything in this scope. 289 // FIXME: The isDeclScope check could be expensive. Can we do better? 290 for (; I != IEnd && S->isDeclScope(*I); ++I) { 291 if ((*I)->getIdentifierNamespace() & NS) { 292 // We found something. Look for anything else in our scope 293 // with this same name and in an acceptable identifier 294 // namespace, so that we can construct an overload set if we 295 // need to. 296 IdentifierResolver::iterator LastI = I; 297 for (++LastI; LastI != IEnd; ++LastI) { 298 if (((*LastI)->getIdentifierNamespace() & NS) == 0 || 299 !S->isDeclScope(*LastI)) 300 break; 301 } 302 return MaybeConstructOverloadSet(Context, I, LastI); 303 } 304 } 305 306 // If there is an entity associated with this scope, it's a 307 // DeclContext. We might need to perform qualified lookup into 308 // it. 309 DeclContext *Ctx = static_cast<DeclContext *>(S->getEntity()); 310 while (Ctx && Ctx->isFunctionOrMethod()) 311 Ctx = Ctx->getParent(); 312 while (Ctx && (Ctx->isNamespace() || Ctx->isCXXRecord())) { 313 // Look for declarations of this name in this scope. 314 DeclContext::lookup_const_iterator I, E; 315 for (llvm::tie(I, E) = Ctx->lookup(Context, Name); I != E; ++I) { 316 // FIXME: Cache this result in the IdResolver 317 if ((*I)->getIdentifierNamespace() & NS) 318 return MaybeConstructOverloadSet(Context, I, E); 319 } 320 321 Ctx = Ctx->getParent(); 322 } 323 324 if (!LookInParent) 325 return 0; 326 } 327 } 328 329 // If we didn't find a use of this identifier, and if the identifier 330 // corresponds to a compiler builtin, create the decl object for the builtin 331 // now, injecting it into translation unit scope, and return it. 332 if (NS & Decl::IDNS_Ordinary) { 333 IdentifierInfo *II = Name.getAsIdentifierInfo(); 334 if (enableLazyBuiltinCreation && II && 335 (LookupCtx == 0 || isa<TranslationUnitDecl>(LookupCtx))) { 336 // If this is a builtin on this (or all) targets, create the decl. 337 if (unsigned BuiltinID = II->getBuiltinID()) 338 return LazilyCreateBuiltin((IdentifierInfo *)II, BuiltinID, S); 339 } 340 if (getLangOptions().ObjC1 && II) { 341 // @interface and @compatibility_alias introduce typedef-like names. 342 // Unlike typedef's, they can only be introduced at file-scope (and are 343 // therefore not scoped decls). They can, however, be shadowed by 344 // other names in IDNS_Ordinary. 345 ObjCInterfaceDeclsTy::iterator IDI = ObjCInterfaceDecls.find(II); 346 if (IDI != ObjCInterfaceDecls.end()) 347 return IDI->second; 348 ObjCAliasTy::iterator I = ObjCAliasDecls.find(II); 349 if (I != ObjCAliasDecls.end()) 350 return I->second->getClassInterface(); 351 } 352 } 353 return 0; 354} 355 356void Sema::InitBuiltinVaListType() { 357 if (!Context.getBuiltinVaListType().isNull()) 358 return; 359 360 IdentifierInfo *VaIdent = &Context.Idents.get("__builtin_va_list"); 361 Decl *VaDecl = LookupDecl(VaIdent, Decl::IDNS_Ordinary, TUScope); 362 TypedefDecl *VaTypedef = cast<TypedefDecl>(VaDecl); 363 Context.setBuiltinVaListType(Context.getTypedefType(VaTypedef)); 364} 365 366/// LazilyCreateBuiltin - The specified Builtin-ID was first used at file scope. 367/// lazily create a decl for it. 368ScopedDecl *Sema::LazilyCreateBuiltin(IdentifierInfo *II, unsigned bid, 369 Scope *S) { 370 Builtin::ID BID = (Builtin::ID)bid; 371 372 if (Context.BuiltinInfo.hasVAListUse(BID)) 373 InitBuiltinVaListType(); 374 375 QualType R = Context.BuiltinInfo.GetBuiltinType(BID, Context); 376 FunctionDecl *New = FunctionDecl::Create(Context, 377 Context.getTranslationUnitDecl(), 378 SourceLocation(), II, R, 379 FunctionDecl::Extern, false, 0); 380 381 // Create Decl objects for each parameter, adding them to the 382 // FunctionDecl. 383 if (FunctionTypeProto *FT = dyn_cast<FunctionTypeProto>(R)) { 384 llvm::SmallVector<ParmVarDecl*, 16> Params; 385 for (unsigned i = 0, e = FT->getNumArgs(); i != e; ++i) 386 Params.push_back(ParmVarDecl::Create(Context, New, SourceLocation(), 0, 387 FT->getArgType(i), VarDecl::None, 0, 388 0)); 389 New->setParams(&Params[0], Params.size()); 390 } 391 392 393 394 // TUScope is the translation-unit scope to insert this function into. 395 PushOnScopeChains(New, TUScope); 396 return New; 397} 398 399/// GetStdNamespace - This method gets the C++ "std" namespace. This is where 400/// everything from the standard library is defined. 401NamespaceDecl *Sema::GetStdNamespace() { 402 if (!StdNamespace) { 403 IdentifierInfo *StdIdent = &PP.getIdentifierTable().get("std"); 404 DeclContext *Global = Context.getTranslationUnitDecl(); 405 Decl *Std = LookupDecl(StdIdent, Decl::IDNS_Tag | Decl::IDNS_Ordinary, 406 0, Global, /*enableLazyBuiltinCreation=*/false); 407 StdNamespace = dyn_cast_or_null<NamespaceDecl>(Std); 408 } 409 return StdNamespace; 410} 411 412/// MergeTypeDefDecl - We just parsed a typedef 'New' which has the same name 413/// and scope as a previous declaration 'Old'. Figure out how to resolve this 414/// situation, merging decls or emitting diagnostics as appropriate. 415/// 416TypedefDecl *Sema::MergeTypeDefDecl(TypedefDecl *New, Decl *OldD) { 417 // Allow multiple definitions for ObjC built-in typedefs. 418 // FIXME: Verify the underlying types are equivalent! 419 if (getLangOptions().ObjC1) { 420 const IdentifierInfo *TypeID = New->getIdentifier(); 421 switch (TypeID->getLength()) { 422 default: break; 423 case 2: 424 if (!TypeID->isStr("id")) 425 break; 426 Context.setObjCIdType(New); 427 return New; 428 case 5: 429 if (!TypeID->isStr("Class")) 430 break; 431 Context.setObjCClassType(New); 432 return New; 433 case 3: 434 if (!TypeID->isStr("SEL")) 435 break; 436 Context.setObjCSelType(New); 437 return New; 438 case 8: 439 if (!TypeID->isStr("Protocol")) 440 break; 441 Context.setObjCProtoType(New->getUnderlyingType()); 442 return New; 443 } 444 // Fall through - the typedef name was not a builtin type. 445 } 446 // Verify the old decl was also a typedef. 447 TypedefDecl *Old = dyn_cast<TypedefDecl>(OldD); 448 if (!Old) { 449 Diag(New->getLocation(), diag::err_redefinition_different_kind) 450 << New->getDeclName(); 451 Diag(OldD->getLocation(), diag::note_previous_definition); 452 return New; 453 } 454 455 // If the typedef types are not identical, reject them in all languages and 456 // with any extensions enabled. 457 if (Old->getUnderlyingType() != New->getUnderlyingType() && 458 Context.getCanonicalType(Old->getUnderlyingType()) != 459 Context.getCanonicalType(New->getUnderlyingType())) { 460 Diag(New->getLocation(), diag::err_redefinition_different_typedef) 461 << New->getUnderlyingType() << Old->getUnderlyingType(); 462 Diag(Old->getLocation(), diag::note_previous_definition); 463 return Old; 464 } 465 466 if (getLangOptions().Microsoft) return New; 467 468 // C++ [dcl.typedef]p2: 469 // In a given non-class scope, a typedef specifier can be used to 470 // redefine the name of any type declared in that scope to refer 471 // to the type to which it already refers. 472 if (getLangOptions().CPlusPlus && !isa<CXXRecordDecl>(CurContext)) 473 return New; 474 475 // In C, redeclaration of a type is a constraint violation (6.7.2.3p1). 476 // Apparently GCC, Intel, and Sun all silently ignore the redeclaration if 477 // *either* declaration is in a system header. The code below implements 478 // this adhoc compatibility rule. FIXME: The following code will not 479 // work properly when compiling ".i" files (containing preprocessed output). 480 if (PP.getDiagnostics().getSuppressSystemWarnings()) { 481 SourceManager &SrcMgr = Context.getSourceManager(); 482 if (SrcMgr.isInSystemHeader(Old->getLocation())) 483 return New; 484 if (SrcMgr.isInSystemHeader(New->getLocation())) 485 return New; 486 } 487 488 Diag(New->getLocation(), diag::err_redefinition) << New->getDeclName(); 489 Diag(Old->getLocation(), diag::note_previous_definition); 490 return New; 491} 492 493/// DeclhasAttr - returns true if decl Declaration already has the target 494/// attribute. 495static bool DeclHasAttr(const Decl *decl, const Attr *target) { 496 for (const Attr *attr = decl->getAttrs(); attr; attr = attr->getNext()) 497 if (attr->getKind() == target->getKind()) 498 return true; 499 500 return false; 501} 502 503/// MergeAttributes - append attributes from the Old decl to the New one. 504static void MergeAttributes(Decl *New, Decl *Old) { 505 Attr *attr = const_cast<Attr*>(Old->getAttrs()), *tmp; 506 507 while (attr) { 508 tmp = attr; 509 attr = attr->getNext(); 510 511 if (!DeclHasAttr(New, tmp)) { 512 tmp->setInherited(true); 513 New->addAttr(tmp); 514 } else { 515 tmp->setNext(0); 516 delete(tmp); 517 } 518 } 519 520 Old->invalidateAttrs(); 521} 522 523/// MergeFunctionDecl - We just parsed a function 'New' from 524/// declarator D which has the same name and scope as a previous 525/// declaration 'Old'. Figure out how to resolve this situation, 526/// merging decls or emitting diagnostics as appropriate. 527/// Redeclaration will be set true if this New is a redeclaration OldD. 528/// 529/// In C++, New and Old must be declarations that are not 530/// overloaded. Use IsOverload to determine whether New and Old are 531/// overloaded, and to select the Old declaration that New should be 532/// merged with. 533FunctionDecl * 534Sema::MergeFunctionDecl(FunctionDecl *New, Decl *OldD, bool &Redeclaration) { 535 assert(!isa<OverloadedFunctionDecl>(OldD) && 536 "Cannot merge with an overloaded function declaration"); 537 538 Redeclaration = false; 539 // Verify the old decl was also a function. 540 FunctionDecl *Old = dyn_cast<FunctionDecl>(OldD); 541 if (!Old) { 542 Diag(New->getLocation(), diag::err_redefinition_different_kind) 543 << New->getDeclName(); 544 Diag(OldD->getLocation(), diag::note_previous_definition); 545 return New; 546 } 547 548 // Determine whether the previous declaration was a definition, 549 // implicit declaration, or a declaration. 550 diag::kind PrevDiag; 551 if (Old->isThisDeclarationADefinition()) 552 PrevDiag = diag::note_previous_definition; 553 else if (Old->isImplicit()) 554 PrevDiag = diag::note_previous_implicit_declaration; 555 else 556 PrevDiag = diag::note_previous_declaration; 557 558 QualType OldQType = Context.getCanonicalType(Old->getType()); 559 QualType NewQType = Context.getCanonicalType(New->getType()); 560 561 if (getLangOptions().CPlusPlus) { 562 // (C++98 13.1p2): 563 // Certain function declarations cannot be overloaded: 564 // -- Function declarations that differ only in the return type 565 // cannot be overloaded. 566 QualType OldReturnType 567 = cast<FunctionType>(OldQType.getTypePtr())->getResultType(); 568 QualType NewReturnType 569 = cast<FunctionType>(NewQType.getTypePtr())->getResultType(); 570 if (OldReturnType != NewReturnType) { 571 Diag(New->getLocation(), diag::err_ovl_diff_return_type); 572 Diag(Old->getLocation(), PrevDiag); 573 Redeclaration = true; 574 return New; 575 } 576 577 const CXXMethodDecl* OldMethod = dyn_cast<CXXMethodDecl>(Old); 578 const CXXMethodDecl* NewMethod = dyn_cast<CXXMethodDecl>(New); 579 if (OldMethod && NewMethod) { 580 // -- Member function declarations with the same name and the 581 // same parameter types cannot be overloaded if any of them 582 // is a static member function declaration. 583 if (OldMethod->isStatic() || NewMethod->isStatic()) { 584 Diag(New->getLocation(), diag::err_ovl_static_nonstatic_member); 585 Diag(Old->getLocation(), PrevDiag); 586 return New; 587 } 588 589 // C++ [class.mem]p1: 590 // [...] A member shall not be declared twice in the 591 // member-specification, except that a nested class or member 592 // class template can be declared and then later defined. 593 if (OldMethod->getLexicalDeclContext() == 594 NewMethod->getLexicalDeclContext()) { 595 unsigned NewDiag; 596 if (isa<CXXConstructorDecl>(OldMethod)) 597 NewDiag = diag::err_constructor_redeclared; 598 else if (isa<CXXDestructorDecl>(NewMethod)) 599 NewDiag = diag::err_destructor_redeclared; 600 else if (isa<CXXConversionDecl>(NewMethod)) 601 NewDiag = diag::err_conv_function_redeclared; 602 else 603 NewDiag = diag::err_member_redeclared; 604 605 Diag(New->getLocation(), NewDiag); 606 Diag(Old->getLocation(), PrevDiag); 607 } 608 } 609 610 // (C++98 8.3.5p3): 611 // All declarations for a function shall agree exactly in both the 612 // return type and the parameter-type-list. 613 if (OldQType == NewQType) { 614 // We have a redeclaration. 615 MergeAttributes(New, Old); 616 Redeclaration = true; 617 return MergeCXXFunctionDecl(New, Old); 618 } 619 620 // Fall through for conflicting redeclarations and redefinitions. 621 } 622 623 // C: Function types need to be compatible, not identical. This handles 624 // duplicate function decls like "void f(int); void f(enum X);" properly. 625 if (!getLangOptions().CPlusPlus && 626 Context.typesAreCompatible(OldQType, NewQType)) { 627 MergeAttributes(New, Old); 628 Redeclaration = true; 629 return New; 630 } 631 632 // A function that has already been declared has been redeclared or defined 633 // with a different type- show appropriate diagnostic 634 635 // TODO: CHECK FOR CONFLICTS, multiple decls with same name in one scope. 636 // TODO: This is totally simplistic. It should handle merging functions 637 // together etc, merging extern int X; int X; ... 638 Diag(New->getLocation(), diag::err_conflicting_types) << New->getDeclName(); 639 Diag(Old->getLocation(), PrevDiag); 640 return New; 641} 642 643/// Predicate for C "tentative" external object definitions (C99 6.9.2). 644static bool isTentativeDefinition(VarDecl *VD) { 645 if (VD->isFileVarDecl()) 646 return (!VD->getInit() && 647 (VD->getStorageClass() == VarDecl::None || 648 VD->getStorageClass() == VarDecl::Static)); 649 return false; 650} 651 652/// CheckForFileScopedRedefinitions - Make sure we forgo redefinition errors 653/// when dealing with C "tentative" external object definitions (C99 6.9.2). 654void Sema::CheckForFileScopedRedefinitions(Scope *S, VarDecl *VD) { 655 bool VDIsTentative = isTentativeDefinition(VD); 656 bool VDIsIncompleteArray = VD->getType()->isIncompleteArrayType(); 657 658 // FIXME: I don't this will actually see all of the 659 // redefinitions. Can't we check this property on-the-fly? 660 for (IdentifierResolver::iterator 661 I = IdResolver.begin(VD->getIdentifier(), 662 VD->getDeclContext(), false/*LookInParentCtx*/), 663 E = IdResolver.end(); I != E; ++I) { 664 if (*I != VD && isDeclInScope(*I, VD->getDeclContext(), S)) { 665 VarDecl *OldDecl = dyn_cast<VarDecl>(*I); 666 667 // Handle the following case: 668 // int a[10]; 669 // int a[]; - the code below makes sure we set the correct type. 670 // int a[11]; - this is an error, size isn't 10. 671 if (OldDecl && VDIsTentative && VDIsIncompleteArray && 672 OldDecl->getType()->isConstantArrayType()) 673 VD->setType(OldDecl->getType()); 674 675 // Check for "tentative" definitions. We can't accomplish this in 676 // MergeVarDecl since the initializer hasn't been attached. 677 if (!OldDecl || isTentativeDefinition(OldDecl) || VDIsTentative) 678 continue; 679 680 // Handle __private_extern__ just like extern. 681 if (OldDecl->getStorageClass() != VarDecl::Extern && 682 OldDecl->getStorageClass() != VarDecl::PrivateExtern && 683 VD->getStorageClass() != VarDecl::Extern && 684 VD->getStorageClass() != VarDecl::PrivateExtern) { 685 Diag(VD->getLocation(), diag::err_redefinition) << VD->getDeclName(); 686 Diag(OldDecl->getLocation(), diag::note_previous_definition); 687 } 688 } 689 } 690} 691 692/// MergeVarDecl - We just parsed a variable 'New' which has the same name 693/// and scope as a previous declaration 'Old'. Figure out how to resolve this 694/// situation, merging decls or emitting diagnostics as appropriate. 695/// 696/// Tentative definition rules (C99 6.9.2p2) are checked by 697/// FinalizeDeclaratorGroup. Unfortunately, we can't analyze tentative 698/// definitions here, since the initializer hasn't been attached. 699/// 700VarDecl *Sema::MergeVarDecl(VarDecl *New, Decl *OldD) { 701 // Verify the old decl was also a variable. 702 VarDecl *Old = dyn_cast<VarDecl>(OldD); 703 if (!Old) { 704 Diag(New->getLocation(), diag::err_redefinition_different_kind) 705 << New->getDeclName(); 706 Diag(OldD->getLocation(), diag::note_previous_definition); 707 return New; 708 } 709 710 MergeAttributes(New, Old); 711 712 // Verify the types match. 713 QualType OldCType = Context.getCanonicalType(Old->getType()); 714 QualType NewCType = Context.getCanonicalType(New->getType()); 715 if (OldCType != NewCType && !Context.typesAreCompatible(OldCType, NewCType)) { 716 Diag(New->getLocation(), diag::err_redefinition) << New->getDeclName(); 717 Diag(Old->getLocation(), diag::note_previous_definition); 718 return New; 719 } 720 // C99 6.2.2p4: Check if we have a static decl followed by a non-static. 721 if (New->getStorageClass() == VarDecl::Static && 722 (Old->getStorageClass() == VarDecl::None || 723 Old->getStorageClass() == VarDecl::Extern)) { 724 Diag(New->getLocation(), diag::err_static_non_static) << New->getDeclName(); 725 Diag(Old->getLocation(), diag::note_previous_definition); 726 return New; 727 } 728 // C99 6.2.2p4: Check if we have a non-static decl followed by a static. 729 if (New->getStorageClass() != VarDecl::Static && 730 Old->getStorageClass() == VarDecl::Static) { 731 Diag(New->getLocation(), diag::err_non_static_static) << New->getDeclName(); 732 Diag(Old->getLocation(), diag::note_previous_definition); 733 return New; 734 } 735 // Variables with external linkage are analyzed in FinalizeDeclaratorGroup. 736 if (New->getStorageClass() != VarDecl::Extern && !New->isFileVarDecl()) { 737 Diag(New->getLocation(), diag::err_redefinition) << New->getDeclName(); 738 Diag(Old->getLocation(), diag::note_previous_definition); 739 } 740 return New; 741} 742 743/// CheckParmsForFunctionDef - Check that the parameters of the given 744/// function are appropriate for the definition of a function. This 745/// takes care of any checks that cannot be performed on the 746/// declaration itself, e.g., that the types of each of the function 747/// parameters are complete. 748bool Sema::CheckParmsForFunctionDef(FunctionDecl *FD) { 749 bool HasInvalidParm = false; 750 for (unsigned p = 0, NumParams = FD->getNumParams(); p < NumParams; ++p) { 751 ParmVarDecl *Param = FD->getParamDecl(p); 752 753 // C99 6.7.5.3p4: the parameters in a parameter type list in a 754 // function declarator that is part of a function definition of 755 // that function shall not have incomplete type. 756 if (Param->getType()->isIncompleteType() && 757 !Param->isInvalidDecl()) { 758 Diag(Param->getLocation(), diag::err_typecheck_decl_incomplete_type) 759 << Param->getType(); 760 Param->setInvalidDecl(); 761 HasInvalidParm = true; 762 } 763 764 // C99 6.9.1p5: If the declarator includes a parameter type list, the 765 // declaration of each parameter shall include an identifier. 766 if (Param->getIdentifier() == 0 && !getLangOptions().CPlusPlus) 767 Diag(Param->getLocation(), diag::err_parameter_name_omitted); 768 } 769 770 return HasInvalidParm; 771} 772 773/// ParsedFreeStandingDeclSpec - This method is invoked when a declspec with 774/// no declarator (e.g. "struct foo;") is parsed. 775Sema::DeclTy *Sema::ParsedFreeStandingDeclSpec(Scope *S, DeclSpec &DS) { 776 // TODO: emit error on 'int;' or 'const enum foo;'. 777 // TODO: emit error on 'typedef int;' 778 // if (!DS.isMissingDeclaratorOk()) Diag(...); 779 780 return dyn_cast_or_null<TagDecl>(static_cast<Decl *>(DS.getTypeRep())); 781} 782 783bool Sema::CheckSingleInitializer(Expr *&Init, QualType DeclType) { 784 // Get the type before calling CheckSingleAssignmentConstraints(), since 785 // it can promote the expression. 786 QualType InitType = Init->getType(); 787 788 if (getLangOptions().CPlusPlus) 789 return PerformCopyInitialization(Init, DeclType, "initializing"); 790 791 AssignConvertType ConvTy = CheckSingleAssignmentConstraints(DeclType, Init); 792 return DiagnoseAssignmentResult(ConvTy, Init->getLocStart(), DeclType, 793 InitType, Init, "initializing"); 794} 795 796bool Sema::CheckStringLiteralInit(StringLiteral *strLiteral, QualType &DeclT) { 797 const ArrayType *AT = Context.getAsArrayType(DeclT); 798 799 if (const IncompleteArrayType *IAT = dyn_cast<IncompleteArrayType>(AT)) { 800 // C99 6.7.8p14. We have an array of character type with unknown size 801 // being initialized to a string literal. 802 llvm::APSInt ConstVal(32); 803 ConstVal = strLiteral->getByteLength() + 1; 804 // Return a new array type (C99 6.7.8p22). 805 DeclT = Context.getConstantArrayType(IAT->getElementType(), ConstVal, 806 ArrayType::Normal, 0); 807 } else { 808 const ConstantArrayType *CAT = cast<ConstantArrayType>(AT); 809 // C99 6.7.8p14. We have an array of character type with known size. 810 // FIXME: Avoid truncation for 64-bit length strings. 811 if (strLiteral->getByteLength() > (unsigned)CAT->getSize().getZExtValue()) 812 Diag(strLiteral->getSourceRange().getBegin(), 813 diag::warn_initializer_string_for_char_array_too_long) 814 << strLiteral->getSourceRange(); 815 } 816 // Set type from "char *" to "constant array of char". 817 strLiteral->setType(DeclT); 818 // For now, we always return false (meaning success). 819 return false; 820} 821 822StringLiteral *Sema::IsStringLiteralInit(Expr *Init, QualType DeclType) { 823 const ArrayType *AT = Context.getAsArrayType(DeclType); 824 if (AT && AT->getElementType()->isCharType()) { 825 return dyn_cast<StringLiteral>(Init); 826 } 827 return 0; 828} 829 830bool Sema::CheckInitializerTypes(Expr *&Init, QualType &DeclType, 831 SourceLocation InitLoc, 832 DeclarationName InitEntity) { 833 if (DeclType->isDependentType() || Init->isTypeDependent()) 834 return false; 835 836 // C++ [dcl.init.ref]p1: 837 // A variable declared to be a T&, that is "reference to type T" 838 // (8.3.2), shall be initialized by an object, or function, of 839 // type T or by an object that can be converted into a T. 840 if (DeclType->isReferenceType()) 841 return CheckReferenceInit(Init, DeclType); 842 843 // C99 6.7.8p3: The type of the entity to be initialized shall be an array 844 // of unknown size ("[]") or an object type that is not a variable array type. 845 if (const VariableArrayType *VAT = Context.getAsVariableArrayType(DeclType)) 846 return Diag(InitLoc, diag::err_variable_object_no_init) 847 << VAT->getSizeExpr()->getSourceRange(); 848 849 InitListExpr *InitList = dyn_cast<InitListExpr>(Init); 850 if (!InitList) { 851 // FIXME: Handle wide strings 852 if (StringLiteral *strLiteral = IsStringLiteralInit(Init, DeclType)) 853 return CheckStringLiteralInit(strLiteral, DeclType); 854 855 // C++ [dcl.init]p14: 856 // -- If the destination type is a (possibly cv-qualified) class 857 // type: 858 if (getLangOptions().CPlusPlus && DeclType->isRecordType()) { 859 QualType DeclTypeC = Context.getCanonicalType(DeclType); 860 QualType InitTypeC = Context.getCanonicalType(Init->getType()); 861 862 // -- If the initialization is direct-initialization, or if it is 863 // copy-initialization where the cv-unqualified version of the 864 // source type is the same class as, or a derived class of, the 865 // class of the destination, constructors are considered. 866 if ((DeclTypeC.getUnqualifiedType() == InitTypeC.getUnqualifiedType()) || 867 IsDerivedFrom(InitTypeC, DeclTypeC)) { 868 CXXConstructorDecl *Constructor 869 = PerformInitializationByConstructor(DeclType, &Init, 1, 870 InitLoc, Init->getSourceRange(), 871 InitEntity, IK_Copy); 872 return Constructor == 0; 873 } 874 875 // -- Otherwise (i.e., for the remaining copy-initialization 876 // cases), user-defined conversion sequences that can 877 // convert from the source type to the destination type or 878 // (when a conversion function is used) to a derived class 879 // thereof are enumerated as described in 13.3.1.4, and the 880 // best one is chosen through overload resolution 881 // (13.3). If the conversion cannot be done or is 882 // ambiguous, the initialization is ill-formed. The 883 // function selected is called with the initializer 884 // expression as its argument; if the function is a 885 // constructor, the call initializes a temporary of the 886 // destination type. 887 // FIXME: We're pretending to do copy elision here; return to 888 // this when we have ASTs for such things. 889 if (!PerformImplicitConversion(Init, DeclType, "initializing")) 890 return false; 891 892 if (InitEntity) 893 return Diag(InitLoc, diag::err_cannot_initialize_decl) 894 << InitEntity << (int)(Init->isLvalue(Context) == Expr::LV_Valid) 895 << Init->getType() << Init->getSourceRange(); 896 else 897 return Diag(InitLoc, diag::err_cannot_initialize_decl_noname) 898 << DeclType << (int)(Init->isLvalue(Context) == Expr::LV_Valid) 899 << Init->getType() << Init->getSourceRange(); 900 } 901 902 // C99 6.7.8p16. 903 if (DeclType->isArrayType()) 904 return Diag(Init->getLocStart(), diag::err_array_init_list_required) 905 << Init->getSourceRange(); 906 907 return CheckSingleInitializer(Init, DeclType); 908 } else if (getLangOptions().CPlusPlus) { 909 // C++ [dcl.init]p14: 910 // [...] If the class is an aggregate (8.5.1), and the initializer 911 // is a brace-enclosed list, see 8.5.1. 912 // 913 // Note: 8.5.1 is handled below; here, we diagnose the case where 914 // we have an initializer list and a destination type that is not 915 // an aggregate. 916 // FIXME: In C++0x, this is yet another form of initialization. 917 if (const RecordType *ClassRec = DeclType->getAsRecordType()) { 918 const CXXRecordDecl *ClassDecl = cast<CXXRecordDecl>(ClassRec->getDecl()); 919 if (!ClassDecl->isAggregate()) 920 return Diag(InitLoc, diag::err_init_non_aggr_init_list) 921 << DeclType << Init->getSourceRange(); 922 } 923 } 924 925 InitListChecker CheckInitList(this, InitList, DeclType); 926 return CheckInitList.HadError(); 927} 928 929/// GetNameForDeclarator - Determine the full declaration name for the 930/// given Declarator. 931DeclarationName Sema::GetNameForDeclarator(Declarator &D) { 932 switch (D.getKind()) { 933 case Declarator::DK_Abstract: 934 assert(D.getIdentifier() == 0 && "abstract declarators have no name"); 935 return DeclarationName(); 936 937 case Declarator::DK_Normal: 938 assert (D.getIdentifier() != 0 && "normal declarators have an identifier"); 939 return DeclarationName(D.getIdentifier()); 940 941 case Declarator::DK_Constructor: { 942 QualType Ty = Context.getTypeDeclType((TypeDecl *)D.getDeclaratorIdType()); 943 Ty = Context.getCanonicalType(Ty); 944 return Context.DeclarationNames.getCXXConstructorName(Ty); 945 } 946 947 case Declarator::DK_Destructor: { 948 QualType Ty = Context.getTypeDeclType((TypeDecl *)D.getDeclaratorIdType()); 949 Ty = Context.getCanonicalType(Ty); 950 return Context.DeclarationNames.getCXXDestructorName(Ty); 951 } 952 953 case Declarator::DK_Conversion: { 954 QualType Ty = QualType::getFromOpaquePtr(D.getDeclaratorIdType()); 955 Ty = Context.getCanonicalType(Ty); 956 return Context.DeclarationNames.getCXXConversionFunctionName(Ty); 957 } 958 959 case Declarator::DK_Operator: 960 assert(D.getIdentifier() == 0 && "operator names have no identifier"); 961 return Context.DeclarationNames.getCXXOperatorName( 962 D.getOverloadedOperator()); 963 } 964 965 assert(false && "Unknown name kind"); 966 return DeclarationName(); 967} 968 969/// isNearlyMatchingMemberFunction - Determine whether the C++ member 970/// functions Declaration and Definition are "nearly" matching. This 971/// heuristic is used to improve diagnostics in the case where an 972/// out-of-line member function definition doesn't match any 973/// declaration within the class. 974static bool isNearlyMatchingMemberFunction(ASTContext &Context, 975 FunctionDecl *Declaration, 976 FunctionDecl *Definition) { 977 if (Declaration->param_size() != Definition->param_size()) 978 return false; 979 for (unsigned Idx = 0; Idx < Declaration->param_size(); ++Idx) { 980 QualType DeclParamTy = Declaration->getParamDecl(Idx)->getType(); 981 QualType DefParamTy = Definition->getParamDecl(Idx)->getType(); 982 983 DeclParamTy = Context.getCanonicalType(DeclParamTy.getNonReferenceType()); 984 DefParamTy = Context.getCanonicalType(DefParamTy.getNonReferenceType()); 985 if (DeclParamTy.getUnqualifiedType() != DefParamTy.getUnqualifiedType()) 986 return false; 987 } 988 989 return true; 990} 991 992Sema::DeclTy * 993Sema::ActOnDeclarator(Scope *S, Declarator &D, DeclTy *lastDecl, 994 bool IsFunctionDefinition) { 995 ScopedDecl *LastDeclarator = dyn_cast_or_null<ScopedDecl>((Decl *)lastDecl); 996 DeclarationName Name = GetNameForDeclarator(D); 997 998 // All of these full declarators require an identifier. If it doesn't have 999 // one, the ParsedFreeStandingDeclSpec action should be used. 1000 if (!Name) { 1001 if (!D.getInvalidType()) // Reject this if we think it is valid. 1002 Diag(D.getDeclSpec().getSourceRange().getBegin(), 1003 diag::err_declarator_need_ident) 1004 << D.getDeclSpec().getSourceRange() << D.getSourceRange(); 1005 return 0; 1006 } 1007 1008 // The scope passed in may not be a decl scope. Zip up the scope tree until 1009 // we find one that is. 1010 while ((S->getFlags() & Scope::DeclScope) == 0 || 1011 (S->getFlags() & Scope::TemplateParamScope) != 0) 1012 S = S->getParent(); 1013 1014 DeclContext *DC; 1015 Decl *PrevDecl; 1016 ScopedDecl *New; 1017 bool InvalidDecl = false; 1018 1019 // See if this is a redefinition of a variable in the same scope. 1020 if (!D.getCXXScopeSpec().isSet()) { 1021 DC = CurContext; 1022 PrevDecl = LookupDecl(Name, Decl::IDNS_Ordinary, S); 1023 } else { // Something like "int foo::x;" 1024 DC = static_cast<DeclContext*>(D.getCXXScopeSpec().getScopeRep()); 1025 PrevDecl = LookupDecl(Name, Decl::IDNS_Ordinary, S, DC); 1026 1027 // C++ 7.3.1.2p2: 1028 // Members (including explicit specializations of templates) of a named 1029 // namespace can also be defined outside that namespace by explicit 1030 // qualification of the name being defined, provided that the entity being 1031 // defined was already declared in the namespace and the definition appears 1032 // after the point of declaration in a namespace that encloses the 1033 // declarations namespace. 1034 // 1035 // Note that we only check the context at this point. We don't yet 1036 // have enough information to make sure that PrevDecl is actually 1037 // the declaration we want to match. For example, given: 1038 // 1039 // class X { 1040 // void f(); 1041 // void f(float); 1042 // }; 1043 // 1044 // void X::f(int) { } // ill-formed 1045 // 1046 // In this case, PrevDecl will point to the overload set 1047 // containing the two f's declared in X, but neither of them 1048 // matches. 1049 if (!CurContext->Encloses(DC)) { 1050 // The qualifying scope doesn't enclose the original declaration. 1051 // Emit diagnostic based on current scope. 1052 SourceLocation L = D.getIdentifierLoc(); 1053 SourceRange R = D.getCXXScopeSpec().getRange(); 1054 if (isa<FunctionDecl>(CurContext)) { 1055 Diag(L, diag::err_invalid_declarator_in_function) << Name << R; 1056 } else { 1057 Diag(L, diag::err_invalid_declarator_scope) 1058 << Name << cast<NamedDecl>(DC)->getDeclName() << R; 1059 } 1060 InvalidDecl = true; 1061 } 1062 } 1063 1064 if (PrevDecl && PrevDecl->isTemplateParameter()) { 1065 // Maybe we will complain about the shadowed template parameter. 1066 InvalidDecl = InvalidDecl 1067 || DiagnoseTemplateParameterShadow(D.getIdentifierLoc(), PrevDecl); 1068 // Just pretend that we didn't see the previous declaration. 1069 PrevDecl = 0; 1070 } 1071 1072 // In C++, the previous declaration we find might be a tag type 1073 // (class or enum). In this case, the new declaration will hide the 1074 // tag type. 1075 if (PrevDecl && PrevDecl->getIdentifierNamespace() == Decl::IDNS_Tag) 1076 PrevDecl = 0; 1077 1078 QualType R = GetTypeForDeclarator(D, S); 1079 assert(!R.isNull() && "GetTypeForDeclarator() returned null type"); 1080 1081 if (D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_typedef) { 1082 // Typedef declarators cannot be qualified (C++ [dcl.meaning]p1). 1083 if (D.getCXXScopeSpec().isSet()) { 1084 Diag(D.getIdentifierLoc(), diag::err_qualified_typedef_declarator) 1085 << D.getCXXScopeSpec().getRange(); 1086 InvalidDecl = true; 1087 // Pretend we didn't see the scope specifier. 1088 DC = 0; 1089 } 1090 1091 // Check that there are no default arguments (C++ only). 1092 if (getLangOptions().CPlusPlus) 1093 CheckExtraCXXDefaultArguments(D); 1094 1095 TypedefDecl *NewTD = ParseTypedefDecl(S, D, R, LastDeclarator); 1096 if (!NewTD) return 0; 1097 1098 // Handle attributes prior to checking for duplicates in MergeVarDecl 1099 ProcessDeclAttributes(NewTD, D); 1100 // Merge the decl with the existing one if appropriate. If the decl is 1101 // in an outer scope, it isn't the same thing. 1102 if (PrevDecl && isDeclInScope(PrevDecl, DC, S)) { 1103 NewTD = MergeTypeDefDecl(NewTD, PrevDecl); 1104 if (NewTD == 0) return 0; 1105 } 1106 New = NewTD; 1107 if (S->getFnParent() == 0) { 1108 // C99 6.7.7p2: If a typedef name specifies a variably modified type 1109 // then it shall have block scope. 1110 if (NewTD->getUnderlyingType()->isVariablyModifiedType()) { 1111 if (NewTD->getUnderlyingType()->isVariableArrayType()) 1112 Diag(D.getIdentifierLoc(), diag::err_vla_decl_in_file_scope); 1113 else 1114 Diag(D.getIdentifierLoc(), diag::err_vm_decl_in_file_scope); 1115 1116 InvalidDecl = true; 1117 } 1118 } 1119 } else if (R.getTypePtr()->isFunctionType()) { 1120 FunctionDecl::StorageClass SC = FunctionDecl::None; 1121 switch (D.getDeclSpec().getStorageClassSpec()) { 1122 default: assert(0 && "Unknown storage class!"); 1123 case DeclSpec::SCS_auto: 1124 case DeclSpec::SCS_register: 1125 case DeclSpec::SCS_mutable: 1126 Diag(D.getIdentifierLoc(), diag::err_typecheck_sclass_func); 1127 InvalidDecl = true; 1128 break; 1129 case DeclSpec::SCS_unspecified: SC = FunctionDecl::None; break; 1130 case DeclSpec::SCS_extern: SC = FunctionDecl::Extern; break; 1131 case DeclSpec::SCS_static: SC = FunctionDecl::Static; break; 1132 case DeclSpec::SCS_private_extern: SC = FunctionDecl::PrivateExtern;break; 1133 } 1134 1135 bool isInline = D.getDeclSpec().isInlineSpecified(); 1136 // bool isVirtual = D.getDeclSpec().isVirtualSpecified(); 1137 bool isExplicit = D.getDeclSpec().isExplicitSpecified(); 1138 1139 FunctionDecl *NewFD; 1140 if (D.getKind() == Declarator::DK_Constructor) { 1141 // This is a C++ constructor declaration. 1142 assert(DC->isCXXRecord() && 1143 "Constructors can only be declared in a member context"); 1144 1145 InvalidDecl = InvalidDecl || CheckConstructorDeclarator(D, R, SC); 1146 1147 // Create the new declaration 1148 NewFD = CXXConstructorDecl::Create(Context, 1149 cast<CXXRecordDecl>(DC), 1150 D.getIdentifierLoc(), Name, R, 1151 isExplicit, isInline, 1152 /*isImplicitlyDeclared=*/false); 1153 1154 if (InvalidDecl) 1155 NewFD->setInvalidDecl(); 1156 } else if (D.getKind() == Declarator::DK_Destructor) { 1157 // This is a C++ destructor declaration. 1158 if (DC->isCXXRecord()) { 1159 InvalidDecl = InvalidDecl || CheckDestructorDeclarator(D, R, SC); 1160 1161 NewFD = CXXDestructorDecl::Create(Context, 1162 cast<CXXRecordDecl>(DC), 1163 D.getIdentifierLoc(), Name, R, 1164 isInline, 1165 /*isImplicitlyDeclared=*/false); 1166 1167 if (InvalidDecl) 1168 NewFD->setInvalidDecl(); 1169 } else { 1170 Diag(D.getIdentifierLoc(), diag::err_destructor_not_member); 1171 1172 // Create a FunctionDecl to satisfy the function definition parsing 1173 // code path. 1174 NewFD = FunctionDecl::Create(Context, DC, D.getIdentifierLoc(), 1175 Name, R, SC, isInline, LastDeclarator, 1176 // FIXME: Move to DeclGroup... 1177 D.getDeclSpec().getSourceRange().getBegin()); 1178 InvalidDecl = true; 1179 NewFD->setInvalidDecl(); 1180 } 1181 } else if (D.getKind() == Declarator::DK_Conversion) { 1182 if (!DC->isCXXRecord()) { 1183 Diag(D.getIdentifierLoc(), 1184 diag::err_conv_function_not_member); 1185 return 0; 1186 } else { 1187 InvalidDecl = InvalidDecl || CheckConversionDeclarator(D, R, SC); 1188 1189 NewFD = CXXConversionDecl::Create(Context, 1190 cast<CXXRecordDecl>(DC), 1191 D.getIdentifierLoc(), Name, R, 1192 isInline, isExplicit); 1193 1194 if (InvalidDecl) 1195 NewFD->setInvalidDecl(); 1196 } 1197 } else if (DC->isCXXRecord()) { 1198 // This is a C++ method declaration. 1199 NewFD = CXXMethodDecl::Create(Context, cast<CXXRecordDecl>(DC), 1200 D.getIdentifierLoc(), Name, R, 1201 (SC == FunctionDecl::Static), isInline, 1202 LastDeclarator); 1203 } else { 1204 NewFD = FunctionDecl::Create(Context, DC, 1205 D.getIdentifierLoc(), 1206 Name, R, SC, isInline, LastDeclarator, 1207 // FIXME: Move to DeclGroup... 1208 D.getDeclSpec().getSourceRange().getBegin()); 1209 } 1210 1211 // Set the lexical context. If the declarator has a C++ 1212 // scope specifier, the lexical context will be different 1213 // from the semantic context. 1214 NewFD->setLexicalDeclContext(CurContext); 1215 1216 // Handle GNU asm-label extension (encoded as an attribute). 1217 if (Expr *E = (Expr*) D.getAsmLabel()) { 1218 // The parser guarantees this is a string. 1219 StringLiteral *SE = cast<StringLiteral>(E); 1220 NewFD->addAttr(new AsmLabelAttr(std::string(SE->getStrData(), 1221 SE->getByteLength()))); 1222 } 1223 1224 // Copy the parameter declarations from the declarator D to 1225 // the function declaration NewFD, if they are available. 1226 if (D.getNumTypeObjects() > 0) { 1227 DeclaratorChunk::FunctionTypeInfo &FTI = D.getTypeObject(0).Fun; 1228 1229 // Create Decl objects for each parameter, adding them to the 1230 // FunctionDecl. 1231 llvm::SmallVector<ParmVarDecl*, 16> Params; 1232 1233 // Check for C99 6.7.5.3p10 - foo(void) is a non-varargs 1234 // function that takes no arguments, not a function that takes a 1235 // single void argument. 1236 // We let through "const void" here because Sema::GetTypeForDeclarator 1237 // already checks for that case. 1238 if (FTI.NumArgs == 1 && !FTI.isVariadic && FTI.ArgInfo[0].Ident == 0 && 1239 FTI.ArgInfo[0].Param && 1240 ((ParmVarDecl*)FTI.ArgInfo[0].Param)->getType()->isVoidType()) { 1241 // empty arg list, don't push any params. 1242 ParmVarDecl *Param = (ParmVarDecl*)FTI.ArgInfo[0].Param; 1243 1244 // In C++, the empty parameter-type-list must be spelled "void"; a 1245 // typedef of void is not permitted. 1246 if (getLangOptions().CPlusPlus && 1247 Param->getType().getUnqualifiedType() != Context.VoidTy) { 1248 Diag(Param->getLocation(), diag::ext_param_typedef_of_void); 1249 } 1250 } else if (FTI.NumArgs > 0 && FTI.ArgInfo[0].Param != 0) { 1251 for (unsigned i = 0, e = FTI.NumArgs; i != e; ++i) 1252 Params.push_back((ParmVarDecl *)FTI.ArgInfo[i].Param); 1253 } 1254 1255 NewFD->setParams(&Params[0], Params.size()); 1256 } else if (R->getAsTypedefType()) { 1257 // When we're declaring a function with a typedef, as in the 1258 // following example, we'll need to synthesize (unnamed) 1259 // parameters for use in the declaration. 1260 // 1261 // @code 1262 // typedef void fn(int); 1263 // fn f; 1264 // @endcode 1265 const FunctionTypeProto *FT = R->getAsFunctionTypeProto(); 1266 if (!FT) { 1267 // This is a typedef of a function with no prototype, so we 1268 // don't need to do anything. 1269 } else if ((FT->getNumArgs() == 0) || 1270 (FT->getNumArgs() == 1 && !FT->isVariadic() && 1271 FT->getArgType(0)->isVoidType())) { 1272 // This is a zero-argument function. We don't need to do anything. 1273 } else { 1274 // Synthesize a parameter for each argument type. 1275 llvm::SmallVector<ParmVarDecl*, 16> Params; 1276 for (FunctionTypeProto::arg_type_iterator ArgType = FT->arg_type_begin(); 1277 ArgType != FT->arg_type_end(); ++ArgType) { 1278 Params.push_back(ParmVarDecl::Create(Context, DC, 1279 SourceLocation(), 0, 1280 *ArgType, VarDecl::None, 1281 0, 0)); 1282 } 1283 1284 NewFD->setParams(&Params[0], Params.size()); 1285 } 1286 } 1287 1288 if (CXXConstructorDecl *Constructor = dyn_cast<CXXConstructorDecl>(NewFD)) 1289 InvalidDecl = InvalidDecl || CheckConstructor(Constructor); 1290 else if (isa<CXXDestructorDecl>(NewFD)) 1291 cast<CXXRecordDecl>(NewFD->getParent())->setUserDeclaredDestructor(true); 1292 else if (CXXConversionDecl *Conversion = dyn_cast<CXXConversionDecl>(NewFD)) 1293 ActOnConversionDeclarator(Conversion); 1294 1295 // Extra checking for C++ overloaded operators (C++ [over.oper]). 1296 if (NewFD->isOverloadedOperator() && 1297 CheckOverloadedOperatorDeclaration(NewFD)) 1298 NewFD->setInvalidDecl(); 1299 1300 // Merge the decl with the existing one if appropriate. Since C functions 1301 // are in a flat namespace, make sure we consider decls in outer scopes. 1302 if (PrevDecl && 1303 (!getLangOptions().CPlusPlus||isDeclInScope(PrevDecl, DC, S))) { 1304 bool Redeclaration = false; 1305 1306 // If C++, determine whether NewFD is an overload of PrevDecl or 1307 // a declaration that requires merging. If it's an overload, 1308 // there's no more work to do here; we'll just add the new 1309 // function to the scope. 1310 OverloadedFunctionDecl::function_iterator MatchedDecl; 1311 if (!getLangOptions().CPlusPlus || 1312 !IsOverload(NewFD, PrevDecl, MatchedDecl)) { 1313 Decl *OldDecl = PrevDecl; 1314 1315 // If PrevDecl was an overloaded function, extract the 1316 // FunctionDecl that matched. 1317 if (isa<OverloadedFunctionDecl>(PrevDecl)) 1318 OldDecl = *MatchedDecl; 1319 1320 // NewFD and PrevDecl represent declarations that need to be 1321 // merged. 1322 NewFD = MergeFunctionDecl(NewFD, OldDecl, Redeclaration); 1323 1324 if (NewFD == 0) return 0; 1325 if (Redeclaration) { 1326 NewFD->setPreviousDeclaration(cast<FunctionDecl>(OldDecl)); 1327 1328 // An out-of-line member function declaration must also be a 1329 // definition (C++ [dcl.meaning]p1). 1330 if (!IsFunctionDefinition && D.getCXXScopeSpec().isSet() && 1331 !InvalidDecl) { 1332 Diag(NewFD->getLocation(), diag::err_out_of_line_declaration) 1333 << D.getCXXScopeSpec().getRange(); 1334 NewFD->setInvalidDecl(); 1335 } 1336 } 1337 } 1338 1339 if (!Redeclaration && D.getCXXScopeSpec().isSet()) { 1340 // The user tried to provide an out-of-line definition for a 1341 // member function, but there was no such member function 1342 // declared (C++ [class.mfct]p2). For example: 1343 // 1344 // class X { 1345 // void f() const; 1346 // }; 1347 // 1348 // void X::f() { } // ill-formed 1349 // 1350 // Complain about this problem, and attempt to suggest close 1351 // matches (e.g., those that differ only in cv-qualifiers and 1352 // whether the parameter types are references). 1353 Diag(D.getIdentifierLoc(), diag::err_member_def_does_not_match) 1354 << cast<CXXRecordDecl>(DC)->getDeclName() 1355 << D.getCXXScopeSpec().getRange(); 1356 InvalidDecl = true; 1357 1358 PrevDecl = LookupDecl(Name, Decl::IDNS_Ordinary, S, DC); 1359 if (!PrevDecl) { 1360 // Nothing to suggest. 1361 } else if (OverloadedFunctionDecl *Ovl 1362 = dyn_cast<OverloadedFunctionDecl>(PrevDecl)) { 1363 for (OverloadedFunctionDecl::function_iterator 1364 Func = Ovl->function_begin(), 1365 FuncEnd = Ovl->function_end(); 1366 Func != FuncEnd; ++Func) { 1367 if (isNearlyMatchingMemberFunction(Context, *Func, NewFD)) 1368 Diag((*Func)->getLocation(), diag::note_member_def_close_match); 1369 1370 } 1371 } else if (CXXMethodDecl *Method = dyn_cast<CXXMethodDecl>(PrevDecl)) { 1372 // Suggest this no matter how mismatched it is; it's the only 1373 // thing we have. 1374 unsigned diag; 1375 if (isNearlyMatchingMemberFunction(Context, Method, NewFD)) 1376 diag = diag::note_member_def_close_match; 1377 else if (Method->getBody()) 1378 diag = diag::note_previous_definition; 1379 else 1380 diag = diag::note_previous_declaration; 1381 Diag(Method->getLocation(), diag); 1382 } 1383 1384 PrevDecl = 0; 1385 } 1386 } 1387 // Handle attributes. We need to have merged decls when handling attributes 1388 // (for example to check for conflicts, etc). 1389 ProcessDeclAttributes(NewFD, D); 1390 New = NewFD; 1391 1392 if (getLangOptions().CPlusPlus) { 1393 // In C++, check default arguments now that we have merged decls. 1394 CheckCXXDefaultArguments(NewFD); 1395 1396 // An out-of-line member function declaration must also be a 1397 // definition (C++ [dcl.meaning]p1). 1398 if (!IsFunctionDefinition && D.getCXXScopeSpec().isSet() && !InvalidDecl) { 1399 Diag(NewFD->getLocation(), diag::err_out_of_line_declaration) 1400 << D.getCXXScopeSpec().getRange(); 1401 InvalidDecl = true; 1402 } 1403 } 1404 } else { 1405 // Check that there are no default arguments (C++ only). 1406 if (getLangOptions().CPlusPlus) 1407 CheckExtraCXXDefaultArguments(D); 1408 1409 if (R.getTypePtr()->isObjCInterfaceType()) { 1410 Diag(D.getIdentifierLoc(), diag::err_statically_allocated_object) 1411 << D.getIdentifier(); 1412 InvalidDecl = true; 1413 } 1414 1415 VarDecl *NewVD; 1416 VarDecl::StorageClass SC; 1417 switch (D.getDeclSpec().getStorageClassSpec()) { 1418 default: assert(0 && "Unknown storage class!"); 1419 case DeclSpec::SCS_unspecified: SC = VarDecl::None; break; 1420 case DeclSpec::SCS_extern: SC = VarDecl::Extern; break; 1421 case DeclSpec::SCS_static: SC = VarDecl::Static; break; 1422 case DeclSpec::SCS_auto: SC = VarDecl::Auto; break; 1423 case DeclSpec::SCS_register: SC = VarDecl::Register; break; 1424 case DeclSpec::SCS_private_extern: SC = VarDecl::PrivateExtern; break; 1425 case DeclSpec::SCS_mutable: 1426 // mutable can only appear on non-static class members, so it's always 1427 // an error here 1428 Diag(D.getIdentifierLoc(), diag::err_mutable_nonmember); 1429 InvalidDecl = true; 1430 SC = VarDecl::None; 1431 break; 1432 } 1433 1434 IdentifierInfo *II = Name.getAsIdentifierInfo(); 1435 if (!II) { 1436 Diag(D.getIdentifierLoc(), diag::err_bad_variable_name) 1437 << Name.getAsString(); 1438 return 0; 1439 } 1440 1441 if (DC->isCXXRecord()) { 1442 // This is a static data member for a C++ class. 1443 NewVD = CXXClassVarDecl::Create(Context, cast<CXXRecordDecl>(DC), 1444 D.getIdentifierLoc(), II, 1445 R, LastDeclarator); 1446 } else { 1447 bool ThreadSpecified = D.getDeclSpec().isThreadSpecified(); 1448 if (S->getFnParent() == 0) { 1449 // C99 6.9p2: The storage-class specifiers auto and register shall not 1450 // appear in the declaration specifiers in an external declaration. 1451 if (SC == VarDecl::Auto || SC == VarDecl::Register) { 1452 Diag(D.getIdentifierLoc(), diag::err_typecheck_sclass_fscope); 1453 InvalidDecl = true; 1454 } 1455 } 1456 NewVD = VarDecl::Create(Context, DC, D.getIdentifierLoc(), 1457 II, R, SC, LastDeclarator, 1458 // FIXME: Move to DeclGroup... 1459 D.getDeclSpec().getSourceRange().getBegin()); 1460 NewVD->setThreadSpecified(ThreadSpecified); 1461 } 1462 // Handle attributes prior to checking for duplicates in MergeVarDecl 1463 ProcessDeclAttributes(NewVD, D); 1464 1465 // Handle GNU asm-label extension (encoded as an attribute). 1466 if (Expr *E = (Expr*) D.getAsmLabel()) { 1467 // The parser guarantees this is a string. 1468 StringLiteral *SE = cast<StringLiteral>(E); 1469 NewVD->addAttr(new AsmLabelAttr(std::string(SE->getStrData(), 1470 SE->getByteLength()))); 1471 } 1472 1473 // Emit an error if an address space was applied to decl with local storage. 1474 // This includes arrays of objects with address space qualifiers, but not 1475 // automatic variables that point to other address spaces. 1476 // ISO/IEC TR 18037 S5.1.2 1477 if (NewVD->hasLocalStorage() && (NewVD->getType().getAddressSpace() != 0)) { 1478 Diag(D.getIdentifierLoc(), diag::err_as_qualified_auto_decl); 1479 InvalidDecl = true; 1480 } 1481 // Merge the decl with the existing one if appropriate. If the decl is 1482 // in an outer scope, it isn't the same thing. 1483 if (PrevDecl && isDeclInScope(PrevDecl, DC, S)) { 1484 if (isa<FieldDecl>(PrevDecl) && D.getCXXScopeSpec().isSet()) { 1485 // The user tried to define a non-static data member 1486 // out-of-line (C++ [dcl.meaning]p1). 1487 Diag(NewVD->getLocation(), diag::err_nonstatic_member_out_of_line) 1488 << D.getCXXScopeSpec().getRange(); 1489 NewVD->Destroy(Context); 1490 return 0; 1491 } 1492 1493 NewVD = MergeVarDecl(NewVD, PrevDecl); 1494 if (NewVD == 0) return 0; 1495 1496 if (D.getCXXScopeSpec().isSet()) { 1497 // No previous declaration in the qualifying scope. 1498 Diag(D.getIdentifierLoc(), diag::err_typecheck_no_member) 1499 << Name << D.getCXXScopeSpec().getRange(); 1500 InvalidDecl = true; 1501 } 1502 } 1503 New = NewVD; 1504 } 1505 1506 // Set the lexical context. If the declarator has a C++ scope specifier, the 1507 // lexical context will be different from the semantic context. 1508 New->setLexicalDeclContext(CurContext); 1509 1510 // If this has an identifier, add it to the scope stack. 1511 if (Name) 1512 PushOnScopeChains(New, S); 1513 // If any semantic error occurred, mark the decl as invalid. 1514 if (D.getInvalidType() || InvalidDecl) 1515 New->setInvalidDecl(); 1516 1517 return New; 1518} 1519 1520void Sema::InitializerElementNotConstant(const Expr *Init) { 1521 Diag(Init->getExprLoc(), diag::err_init_element_not_constant) 1522 << Init->getSourceRange(); 1523} 1524 1525bool Sema::CheckAddressConstantExpressionLValue(const Expr* Init) { 1526 switch (Init->getStmtClass()) { 1527 default: 1528 InitializerElementNotConstant(Init); 1529 return true; 1530 case Expr::ParenExprClass: { 1531 const ParenExpr* PE = cast<ParenExpr>(Init); 1532 return CheckAddressConstantExpressionLValue(PE->getSubExpr()); 1533 } 1534 case Expr::CompoundLiteralExprClass: 1535 return cast<CompoundLiteralExpr>(Init)->isFileScope(); 1536 case Expr::DeclRefExprClass: { 1537 const Decl *D = cast<DeclRefExpr>(Init)->getDecl(); 1538 if (const VarDecl *VD = dyn_cast<VarDecl>(D)) { 1539 if (VD->hasGlobalStorage()) 1540 return false; 1541 InitializerElementNotConstant(Init); 1542 return true; 1543 } 1544 if (isa<FunctionDecl>(D)) 1545 return false; 1546 InitializerElementNotConstant(Init); 1547 return true; 1548 } 1549 case Expr::MemberExprClass: { 1550 const MemberExpr *M = cast<MemberExpr>(Init); 1551 if (M->isArrow()) 1552 return CheckAddressConstantExpression(M->getBase()); 1553 return CheckAddressConstantExpressionLValue(M->getBase()); 1554 } 1555 case Expr::ArraySubscriptExprClass: { 1556 // FIXME: Should we pedwarn for "x[0+0]" (where x is a pointer)? 1557 const ArraySubscriptExpr *ASE = cast<ArraySubscriptExpr>(Init); 1558 return CheckAddressConstantExpression(ASE->getBase()) || 1559 CheckArithmeticConstantExpression(ASE->getIdx()); 1560 } 1561 case Expr::StringLiteralClass: 1562 case Expr::PredefinedExprClass: 1563 return false; 1564 case Expr::UnaryOperatorClass: { 1565 const UnaryOperator *Exp = cast<UnaryOperator>(Init); 1566 1567 // C99 6.6p9 1568 if (Exp->getOpcode() == UnaryOperator::Deref) 1569 return CheckAddressConstantExpression(Exp->getSubExpr()); 1570 1571 InitializerElementNotConstant(Init); 1572 return true; 1573 } 1574 } 1575} 1576 1577bool Sema::CheckAddressConstantExpression(const Expr* Init) { 1578 switch (Init->getStmtClass()) { 1579 default: 1580 InitializerElementNotConstant(Init); 1581 return true; 1582 case Expr::ParenExprClass: 1583 return CheckAddressConstantExpression(cast<ParenExpr>(Init)->getSubExpr()); 1584 case Expr::StringLiteralClass: 1585 case Expr::ObjCStringLiteralClass: 1586 return false; 1587 case Expr::CallExprClass: 1588 case Expr::CXXOperatorCallExprClass: 1589 // __builtin___CFStringMakeConstantString is a valid constant l-value. 1590 if (cast<CallExpr>(Init)->isBuiltinCall() == 1591 Builtin::BI__builtin___CFStringMakeConstantString) 1592 return false; 1593 1594 InitializerElementNotConstant(Init); 1595 return true; 1596 1597 case Expr::UnaryOperatorClass: { 1598 const UnaryOperator *Exp = cast<UnaryOperator>(Init); 1599 1600 // C99 6.6p9 1601 if (Exp->getOpcode() == UnaryOperator::AddrOf) 1602 return CheckAddressConstantExpressionLValue(Exp->getSubExpr()); 1603 1604 if (Exp->getOpcode() == UnaryOperator::Extension) 1605 return CheckAddressConstantExpression(Exp->getSubExpr()); 1606 1607 InitializerElementNotConstant(Init); 1608 return true; 1609 } 1610 case Expr::BinaryOperatorClass: { 1611 // FIXME: Should we pedwarn for expressions like "a + 1 + 2"? 1612 const BinaryOperator *Exp = cast<BinaryOperator>(Init); 1613 1614 Expr *PExp = Exp->getLHS(); 1615 Expr *IExp = Exp->getRHS(); 1616 if (IExp->getType()->isPointerType()) 1617 std::swap(PExp, IExp); 1618 1619 // FIXME: Should we pedwarn if IExp isn't an integer constant expression? 1620 return CheckAddressConstantExpression(PExp) || 1621 CheckArithmeticConstantExpression(IExp); 1622 } 1623 case Expr::ImplicitCastExprClass: 1624 case Expr::CStyleCastExprClass: { 1625 const Expr* SubExpr = cast<CastExpr>(Init)->getSubExpr(); 1626 if (Init->getStmtClass() == Expr::ImplicitCastExprClass) { 1627 // Check for implicit promotion 1628 if (SubExpr->getType()->isFunctionType() || 1629 SubExpr->getType()->isArrayType()) 1630 return CheckAddressConstantExpressionLValue(SubExpr); 1631 } 1632 1633 // Check for pointer->pointer cast 1634 if (SubExpr->getType()->isPointerType()) 1635 return CheckAddressConstantExpression(SubExpr); 1636 1637 if (SubExpr->getType()->isIntegralType()) { 1638 // Check for the special-case of a pointer->int->pointer cast; 1639 // this isn't standard, but some code requires it. See 1640 // PR2720 for an example. 1641 if (const CastExpr* SubCast = dyn_cast<CastExpr>(SubExpr)) { 1642 if (SubCast->getSubExpr()->getType()->isPointerType()) { 1643 unsigned IntWidth = Context.getIntWidth(SubCast->getType()); 1644 unsigned PointerWidth = Context.getTypeSize(Context.VoidPtrTy); 1645 if (IntWidth >= PointerWidth) { 1646 return CheckAddressConstantExpression(SubCast->getSubExpr()); 1647 } 1648 } 1649 } 1650 } 1651 if (SubExpr->getType()->isArithmeticType()) { 1652 return CheckArithmeticConstantExpression(SubExpr); 1653 } 1654 1655 InitializerElementNotConstant(Init); 1656 return true; 1657 } 1658 case Expr::ConditionalOperatorClass: { 1659 // FIXME: Should we pedwarn here? 1660 const ConditionalOperator *Exp = cast<ConditionalOperator>(Init); 1661 if (!Exp->getCond()->getType()->isArithmeticType()) { 1662 InitializerElementNotConstant(Init); 1663 return true; 1664 } 1665 if (CheckArithmeticConstantExpression(Exp->getCond())) 1666 return true; 1667 if (Exp->getLHS() && 1668 CheckAddressConstantExpression(Exp->getLHS())) 1669 return true; 1670 return CheckAddressConstantExpression(Exp->getRHS()); 1671 } 1672 case Expr::AddrLabelExprClass: 1673 return false; 1674 } 1675} 1676 1677static const Expr* FindExpressionBaseAddress(const Expr* E); 1678 1679static const Expr* FindExpressionBaseAddressLValue(const Expr* E) { 1680 switch (E->getStmtClass()) { 1681 default: 1682 return E; 1683 case Expr::ParenExprClass: { 1684 const ParenExpr* PE = cast<ParenExpr>(E); 1685 return FindExpressionBaseAddressLValue(PE->getSubExpr()); 1686 } 1687 case Expr::MemberExprClass: { 1688 const MemberExpr *M = cast<MemberExpr>(E); 1689 if (M->isArrow()) 1690 return FindExpressionBaseAddress(M->getBase()); 1691 return FindExpressionBaseAddressLValue(M->getBase()); 1692 } 1693 case Expr::ArraySubscriptExprClass: { 1694 const ArraySubscriptExpr *ASE = cast<ArraySubscriptExpr>(E); 1695 return FindExpressionBaseAddress(ASE->getBase()); 1696 } 1697 case Expr::UnaryOperatorClass: { 1698 const UnaryOperator *Exp = cast<UnaryOperator>(E); 1699 1700 if (Exp->getOpcode() == UnaryOperator::Deref) 1701 return FindExpressionBaseAddress(Exp->getSubExpr()); 1702 1703 return E; 1704 } 1705 } 1706} 1707 1708static const Expr* FindExpressionBaseAddress(const Expr* E) { 1709 switch (E->getStmtClass()) { 1710 default: 1711 return E; 1712 case Expr::ParenExprClass: { 1713 const ParenExpr* PE = cast<ParenExpr>(E); 1714 return FindExpressionBaseAddress(PE->getSubExpr()); 1715 } 1716 case Expr::UnaryOperatorClass: { 1717 const UnaryOperator *Exp = cast<UnaryOperator>(E); 1718 1719 // C99 6.6p9 1720 if (Exp->getOpcode() == UnaryOperator::AddrOf) 1721 return FindExpressionBaseAddressLValue(Exp->getSubExpr()); 1722 1723 if (Exp->getOpcode() == UnaryOperator::Extension) 1724 return FindExpressionBaseAddress(Exp->getSubExpr()); 1725 1726 return E; 1727 } 1728 case Expr::BinaryOperatorClass: { 1729 const BinaryOperator *Exp = cast<BinaryOperator>(E); 1730 1731 Expr *PExp = Exp->getLHS(); 1732 Expr *IExp = Exp->getRHS(); 1733 if (IExp->getType()->isPointerType()) 1734 std::swap(PExp, IExp); 1735 1736 return FindExpressionBaseAddress(PExp); 1737 } 1738 case Expr::ImplicitCastExprClass: { 1739 const Expr* SubExpr = cast<ImplicitCastExpr>(E)->getSubExpr(); 1740 1741 // Check for implicit promotion 1742 if (SubExpr->getType()->isFunctionType() || 1743 SubExpr->getType()->isArrayType()) 1744 return FindExpressionBaseAddressLValue(SubExpr); 1745 1746 // Check for pointer->pointer cast 1747 if (SubExpr->getType()->isPointerType()) 1748 return FindExpressionBaseAddress(SubExpr); 1749 1750 // We assume that we have an arithmetic expression here; 1751 // if we don't, we'll figure it out later 1752 return 0; 1753 } 1754 case Expr::CStyleCastExprClass: { 1755 const Expr* SubExpr = cast<CastExpr>(E)->getSubExpr(); 1756 1757 // Check for pointer->pointer cast 1758 if (SubExpr->getType()->isPointerType()) 1759 return FindExpressionBaseAddress(SubExpr); 1760 1761 // We assume that we have an arithmetic expression here; 1762 // if we don't, we'll figure it out later 1763 return 0; 1764 } 1765 } 1766} 1767 1768bool Sema::CheckArithmeticConstantExpression(const Expr* Init) { 1769 switch (Init->getStmtClass()) { 1770 default: 1771 InitializerElementNotConstant(Init); 1772 return true; 1773 case Expr::ParenExprClass: { 1774 const ParenExpr* PE = cast<ParenExpr>(Init); 1775 return CheckArithmeticConstantExpression(PE->getSubExpr()); 1776 } 1777 case Expr::FloatingLiteralClass: 1778 case Expr::IntegerLiteralClass: 1779 case Expr::CharacterLiteralClass: 1780 case Expr::ImaginaryLiteralClass: 1781 case Expr::TypesCompatibleExprClass: 1782 case Expr::CXXBoolLiteralExprClass: 1783 return false; 1784 case Expr::CallExprClass: 1785 case Expr::CXXOperatorCallExprClass: { 1786 const CallExpr *CE = cast<CallExpr>(Init); 1787 1788 // Allow any constant foldable calls to builtins. 1789 if (CE->isBuiltinCall() && CE->isEvaluatable(Context)) 1790 return false; 1791 1792 InitializerElementNotConstant(Init); 1793 return true; 1794 } 1795 case Expr::DeclRefExprClass: { 1796 const Decl *D = cast<DeclRefExpr>(Init)->getDecl(); 1797 if (isa<EnumConstantDecl>(D)) 1798 return false; 1799 InitializerElementNotConstant(Init); 1800 return true; 1801 } 1802 case Expr::CompoundLiteralExprClass: 1803 // Allow "(vector type){2,4}"; normal C constraints don't allow this, 1804 // but vectors are allowed to be magic. 1805 if (Init->getType()->isVectorType()) 1806 return false; 1807 InitializerElementNotConstant(Init); 1808 return true; 1809 case Expr::UnaryOperatorClass: { 1810 const UnaryOperator *Exp = cast<UnaryOperator>(Init); 1811 1812 switch (Exp->getOpcode()) { 1813 // Address, indirect, pre/post inc/dec, etc are not valid constant exprs. 1814 // See C99 6.6p3. 1815 default: 1816 InitializerElementNotConstant(Init); 1817 return true; 1818 case UnaryOperator::OffsetOf: 1819 if (Exp->getSubExpr()->getType()->isConstantSizeType()) 1820 return false; 1821 InitializerElementNotConstant(Init); 1822 return true; 1823 case UnaryOperator::Extension: 1824 case UnaryOperator::LNot: 1825 case UnaryOperator::Plus: 1826 case UnaryOperator::Minus: 1827 case UnaryOperator::Not: 1828 return CheckArithmeticConstantExpression(Exp->getSubExpr()); 1829 } 1830 } 1831 case Expr::SizeOfAlignOfExprClass: { 1832 const SizeOfAlignOfExpr *Exp = cast<SizeOfAlignOfExpr>(Init); 1833 // Special check for void types, which are allowed as an extension 1834 if (Exp->getTypeOfArgument()->isVoidType()) 1835 return false; 1836 // alignof always evaluates to a constant. 1837 // FIXME: is sizeof(int[3.0]) a constant expression? 1838 if (Exp->isSizeOf() && !Exp->getTypeOfArgument()->isConstantSizeType()) { 1839 InitializerElementNotConstant(Init); 1840 return true; 1841 } 1842 return false; 1843 } 1844 case Expr::BinaryOperatorClass: { 1845 const BinaryOperator *Exp = cast<BinaryOperator>(Init); 1846 1847 if (Exp->getLHS()->getType()->isArithmeticType() && 1848 Exp->getRHS()->getType()->isArithmeticType()) { 1849 return CheckArithmeticConstantExpression(Exp->getLHS()) || 1850 CheckArithmeticConstantExpression(Exp->getRHS()); 1851 } 1852 1853 if (Exp->getLHS()->getType()->isPointerType() && 1854 Exp->getRHS()->getType()->isPointerType()) { 1855 const Expr* LHSBase = FindExpressionBaseAddress(Exp->getLHS()); 1856 const Expr* RHSBase = FindExpressionBaseAddress(Exp->getRHS()); 1857 1858 // Only allow a null (constant integer) base; we could 1859 // allow some additional cases if necessary, but this 1860 // is sufficient to cover offsetof-like constructs. 1861 if (!LHSBase && !RHSBase) { 1862 return CheckAddressConstantExpression(Exp->getLHS()) || 1863 CheckAddressConstantExpression(Exp->getRHS()); 1864 } 1865 } 1866 1867 InitializerElementNotConstant(Init); 1868 return true; 1869 } 1870 case Expr::ImplicitCastExprClass: 1871 case Expr::CStyleCastExprClass: { 1872 const Expr *SubExpr = cast<CastExpr>(Init)->getSubExpr(); 1873 if (SubExpr->getType()->isArithmeticType()) 1874 return CheckArithmeticConstantExpression(SubExpr); 1875 1876 if (SubExpr->getType()->isPointerType()) { 1877 const Expr* Base = FindExpressionBaseAddress(SubExpr); 1878 // If the pointer has a null base, this is an offsetof-like construct 1879 if (!Base) 1880 return CheckAddressConstantExpression(SubExpr); 1881 } 1882 1883 InitializerElementNotConstant(Init); 1884 return true; 1885 } 1886 case Expr::ConditionalOperatorClass: { 1887 const ConditionalOperator *Exp = cast<ConditionalOperator>(Init); 1888 1889 // If GNU extensions are disabled, we require all operands to be arithmetic 1890 // constant expressions. 1891 if (getLangOptions().NoExtensions) { 1892 return CheckArithmeticConstantExpression(Exp->getCond()) || 1893 (Exp->getLHS() && CheckArithmeticConstantExpression(Exp->getLHS())) || 1894 CheckArithmeticConstantExpression(Exp->getRHS()); 1895 } 1896 1897 // Otherwise, we have to emulate some of the behavior of fold here. 1898 // Basically GCC treats things like "4 ? 1 : somefunc()" as a constant 1899 // because it can constant fold things away. To retain compatibility with 1900 // GCC code, we see if we can fold the condition to a constant (which we 1901 // should always be able to do in theory). If so, we only require the 1902 // specified arm of the conditional to be a constant. This is a horrible 1903 // hack, but is require by real world code that uses __builtin_constant_p. 1904 Expr::EvalResult EvalResult; 1905 if (!Exp->getCond()->Evaluate(EvalResult, Context) || 1906 EvalResult.HasSideEffects) { 1907 // If Evaluate couldn't fold it, CheckArithmeticConstantExpression 1908 // won't be able to either. Use it to emit the diagnostic though. 1909 bool Res = CheckArithmeticConstantExpression(Exp->getCond()); 1910 assert(Res && "Evaluate couldn't evaluate this constant?"); 1911 return Res; 1912 } 1913 1914 // Verify that the side following the condition is also a constant. 1915 const Expr *TrueSide = Exp->getLHS(), *FalseSide = Exp->getRHS(); 1916 if (EvalResult.Val.getInt() == 0) 1917 std::swap(TrueSide, FalseSide); 1918 1919 if (TrueSide && CheckArithmeticConstantExpression(TrueSide)) 1920 return true; 1921 1922 // Okay, the evaluated side evaluates to a constant, so we accept this. 1923 // Check to see if the other side is obviously not a constant. If so, 1924 // emit a warning that this is a GNU extension. 1925 if (FalseSide && !FalseSide->isEvaluatable(Context)) 1926 Diag(Init->getExprLoc(), 1927 diag::ext_typecheck_expression_not_constant_but_accepted) 1928 << FalseSide->getSourceRange(); 1929 return false; 1930 } 1931 } 1932} 1933 1934bool Sema::CheckForConstantInitializer(Expr *Init, QualType DclT) { 1935 Expr::EvalResult Result; 1936 1937 Init = Init->IgnoreParens(); 1938 1939 if (Init->Evaluate(Result, Context) && !Result.HasSideEffects) 1940 return false; 1941 1942 // Look through CXXDefaultArgExprs; they have no meaning in this context. 1943 if (CXXDefaultArgExpr* DAE = dyn_cast<CXXDefaultArgExpr>(Init)) 1944 return CheckForConstantInitializer(DAE->getExpr(), DclT); 1945 1946 if (CompoundLiteralExpr *e = dyn_cast<CompoundLiteralExpr>(Init)) 1947 return CheckForConstantInitializer(e->getInitializer(), DclT); 1948 1949 if (InitListExpr *Exp = dyn_cast<InitListExpr>(Init)) { 1950 unsigned numInits = Exp->getNumInits(); 1951 for (unsigned i = 0; i < numInits; i++) { 1952 // FIXME: Need to get the type of the declaration for C++, 1953 // because it could be a reference? 1954 if (CheckForConstantInitializer(Exp->getInit(i), 1955 Exp->getInit(i)->getType())) 1956 return true; 1957 } 1958 return false; 1959 } 1960 1961 // FIXME: We can probably remove some of this code below, now that 1962 // Expr::Evaluate is doing the heavy lifting for scalars. 1963 1964 if (Init->isNullPointerConstant(Context)) 1965 return false; 1966 if (Init->getType()->isArithmeticType()) { 1967 QualType InitTy = Context.getCanonicalType(Init->getType()) 1968 .getUnqualifiedType(); 1969 if (InitTy == Context.BoolTy) { 1970 // Special handling for pointers implicitly cast to bool; 1971 // (e.g. "_Bool rr = &rr;"). This is only legal at the top level. 1972 if (ImplicitCastExpr* ICE = dyn_cast<ImplicitCastExpr>(Init)) { 1973 Expr* SubE = ICE->getSubExpr(); 1974 if (SubE->getType()->isPointerType() || 1975 SubE->getType()->isArrayType() || 1976 SubE->getType()->isFunctionType()) { 1977 return CheckAddressConstantExpression(Init); 1978 } 1979 } 1980 } else if (InitTy->isIntegralType()) { 1981 Expr* SubE = 0; 1982 if (CastExpr* CE = dyn_cast<CastExpr>(Init)) 1983 SubE = CE->getSubExpr(); 1984 // Special check for pointer cast to int; we allow as an extension 1985 // an address constant cast to an integer if the integer 1986 // is of an appropriate width (this sort of code is apparently used 1987 // in some places). 1988 // FIXME: Add pedwarn? 1989 // FIXME: Don't allow bitfields here! Need the FieldDecl for that. 1990 if (SubE && (SubE->getType()->isPointerType() || 1991 SubE->getType()->isArrayType() || 1992 SubE->getType()->isFunctionType())) { 1993 unsigned IntWidth = Context.getTypeSize(Init->getType()); 1994 unsigned PointerWidth = Context.getTypeSize(Context.VoidPtrTy); 1995 if (IntWidth >= PointerWidth) 1996 return CheckAddressConstantExpression(Init); 1997 } 1998 } 1999 2000 return CheckArithmeticConstantExpression(Init); 2001 } 2002 2003 if (Init->getType()->isPointerType()) 2004 return CheckAddressConstantExpression(Init); 2005 2006 // An array type at the top level that isn't an init-list must 2007 // be a string literal 2008 if (Init->getType()->isArrayType()) 2009 return false; 2010 2011 if (Init->getType()->isFunctionType()) 2012 return false; 2013 2014 // Allow block exprs at top level. 2015 if (Init->getType()->isBlockPointerType()) 2016 return false; 2017 2018 InitializerElementNotConstant(Init); 2019 return true; 2020} 2021 2022void Sema::AddInitializerToDecl(DeclTy *dcl, ExprArg init) { 2023 Decl *RealDecl = static_cast<Decl *>(dcl); 2024 Expr *Init = static_cast<Expr *>(init.release()); 2025 assert(Init && "missing initializer"); 2026 2027 // If there is no declaration, there was an error parsing it. Just ignore 2028 // the initializer. 2029 if (RealDecl == 0) { 2030 delete Init; 2031 return; 2032 } 2033 2034 VarDecl *VDecl = dyn_cast<VarDecl>(RealDecl); 2035 if (!VDecl) { 2036 Diag(dyn_cast<ScopedDecl>(RealDecl)->getLocation(), 2037 diag::err_illegal_initializer); 2038 RealDecl->setInvalidDecl(); 2039 return; 2040 } 2041 // Get the decls type and save a reference for later, since 2042 // CheckInitializerTypes may change it. 2043 QualType DclT = VDecl->getType(), SavT = DclT; 2044 if (VDecl->isBlockVarDecl()) { 2045 VarDecl::StorageClass SC = VDecl->getStorageClass(); 2046 if (SC == VarDecl::Extern) { // C99 6.7.8p5 2047 Diag(VDecl->getLocation(), diag::err_block_extern_cant_init); 2048 VDecl->setInvalidDecl(); 2049 } else if (!VDecl->isInvalidDecl()) { 2050 if (CheckInitializerTypes(Init, DclT, VDecl->getLocation(), 2051 VDecl->getDeclName())) 2052 VDecl->setInvalidDecl(); 2053 2054 // C++ 3.6.2p2, allow dynamic initialization of static initializers. 2055 if (!getLangOptions().CPlusPlus) { 2056 if (SC == VarDecl::Static) // C99 6.7.8p4. 2057 CheckForConstantInitializer(Init, DclT); 2058 } 2059 } 2060 } else if (VDecl->isFileVarDecl()) { 2061 if (VDecl->getStorageClass() == VarDecl::Extern) 2062 Diag(VDecl->getLocation(), diag::warn_extern_init); 2063 if (!VDecl->isInvalidDecl()) 2064 if (CheckInitializerTypes(Init, DclT, VDecl->getLocation(), 2065 VDecl->getDeclName())) 2066 VDecl->setInvalidDecl(); 2067 2068 // C++ 3.6.2p2, allow dynamic initialization of static initializers. 2069 if (!getLangOptions().CPlusPlus) { 2070 // C99 6.7.8p4. All file scoped initializers need to be constant. 2071 CheckForConstantInitializer(Init, DclT); 2072 } 2073 } 2074 // If the type changed, it means we had an incomplete type that was 2075 // completed by the initializer. For example: 2076 // int ary[] = { 1, 3, 5 }; 2077 // "ary" transitions from a VariableArrayType to a ConstantArrayType. 2078 if (!VDecl->isInvalidDecl() && (DclT != SavT)) { 2079 VDecl->setType(DclT); 2080 Init->setType(DclT); 2081 } 2082 2083 // Attach the initializer to the decl. 2084 VDecl->setInit(Init); 2085 return; 2086} 2087 2088void Sema::ActOnUninitializedDecl(DeclTy *dcl) { 2089 Decl *RealDecl = static_cast<Decl *>(dcl); 2090 2091 // If there is no declaration, there was an error parsing it. Just ignore it. 2092 if (RealDecl == 0) 2093 return; 2094 2095 if (VarDecl *Var = dyn_cast<VarDecl>(RealDecl)) { 2096 QualType Type = Var->getType(); 2097 // C++ [dcl.init.ref]p3: 2098 // The initializer can be omitted for a reference only in a 2099 // parameter declaration (8.3.5), in the declaration of a 2100 // function return type, in the declaration of a class member 2101 // within its class declaration (9.2), and where the extern 2102 // specifier is explicitly used. 2103 if (Type->isReferenceType() && 2104 Var->getStorageClass() != VarDecl::Extern && 2105 Var->getStorageClass() != VarDecl::PrivateExtern) { 2106 Diag(Var->getLocation(), diag::err_reference_var_requires_init) 2107 << Var->getDeclName() 2108 << SourceRange(Var->getLocation(), Var->getLocation()); 2109 Var->setInvalidDecl(); 2110 return; 2111 } 2112 2113 // C++ [dcl.init]p9: 2114 // 2115 // If no initializer is specified for an object, and the object 2116 // is of (possibly cv-qualified) non-POD class type (or array 2117 // thereof), the object shall be default-initialized; if the 2118 // object is of const-qualified type, the underlying class type 2119 // shall have a user-declared default constructor. 2120 if (getLangOptions().CPlusPlus) { 2121 QualType InitType = Type; 2122 if (const ArrayType *Array = Context.getAsArrayType(Type)) 2123 InitType = Array->getElementType(); 2124 if (Var->getStorageClass() != VarDecl::Extern && 2125 Var->getStorageClass() != VarDecl::PrivateExtern && 2126 InitType->isRecordType()) { 2127 const CXXConstructorDecl *Constructor 2128 = PerformInitializationByConstructor(InitType, 0, 0, 2129 Var->getLocation(), 2130 SourceRange(Var->getLocation(), 2131 Var->getLocation()), 2132 Var->getDeclName(), 2133 IK_Default); 2134 if (!Constructor) 2135 Var->setInvalidDecl(); 2136 } 2137 } 2138 2139#if 0 2140 // FIXME: Temporarily disabled because we are not properly parsing 2141 // linkage specifications on declarations, e.g., 2142 // 2143 // extern "C" const CGPoint CGPointerZero; 2144 // 2145 // C++ [dcl.init]p9: 2146 // 2147 // If no initializer is specified for an object, and the 2148 // object is of (possibly cv-qualified) non-POD class type (or 2149 // array thereof), the object shall be default-initialized; if 2150 // the object is of const-qualified type, the underlying class 2151 // type shall have a user-declared default 2152 // constructor. Otherwise, if no initializer is specified for 2153 // an object, the object and its subobjects, if any, have an 2154 // indeterminate initial value; if the object or any of its 2155 // subobjects are of const-qualified type, the program is 2156 // ill-formed. 2157 // 2158 // This isn't technically an error in C, so we don't diagnose it. 2159 // 2160 // FIXME: Actually perform the POD/user-defined default 2161 // constructor check. 2162 if (getLangOptions().CPlusPlus && 2163 Context.getCanonicalType(Type).isConstQualified() && 2164 Var->getStorageClass() != VarDecl::Extern) 2165 Diag(Var->getLocation(), diag::err_const_var_requires_init) 2166 << Var->getName() 2167 << SourceRange(Var->getLocation(), Var->getLocation()); 2168#endif 2169 } 2170} 2171 2172/// The declarators are chained together backwards, reverse the list. 2173Sema::DeclTy *Sema::FinalizeDeclaratorGroup(Scope *S, DeclTy *group) { 2174 // Often we have single declarators, handle them quickly. 2175 Decl *GroupDecl = static_cast<Decl*>(group); 2176 if (GroupDecl == 0) 2177 return 0; 2178 2179 ScopedDecl *Group = dyn_cast<ScopedDecl>(GroupDecl); 2180 ScopedDecl *NewGroup = 0; 2181 if (Group->getNextDeclarator() == 0) 2182 NewGroup = Group; 2183 else { // reverse the list. 2184 while (Group) { 2185 ScopedDecl *Next = Group->getNextDeclarator(); 2186 Group->setNextDeclarator(NewGroup); 2187 NewGroup = Group; 2188 Group = Next; 2189 } 2190 } 2191 // Perform semantic analysis that depends on having fully processed both 2192 // the declarator and initializer. 2193 for (ScopedDecl *ID = NewGroup; ID; ID = ID->getNextDeclarator()) { 2194 VarDecl *IDecl = dyn_cast<VarDecl>(ID); 2195 if (!IDecl) 2196 continue; 2197 QualType T = IDecl->getType(); 2198 2199 if (T->isVariableArrayType()) { 2200 const VariableArrayType *VAT = Context.getAsVariableArrayType(T); 2201 2202 // FIXME: This won't give the correct result for 2203 // int a[10][n]; 2204 SourceRange SizeRange = VAT->getSizeExpr()->getSourceRange(); 2205 if (IDecl->isFileVarDecl()) { 2206 Diag(IDecl->getLocation(), diag::err_vla_decl_in_file_scope) << 2207 SizeRange; 2208 2209 IDecl->setInvalidDecl(); 2210 } else { 2211 // C99 6.7.5.2p2: If an identifier is declared to be an object with 2212 // static storage duration, it shall not have a variable length array. 2213 if (IDecl->getStorageClass() == VarDecl::Static) { 2214 Diag(IDecl->getLocation(), diag::err_vla_decl_has_static_storage) 2215 << SizeRange; 2216 IDecl->setInvalidDecl(); 2217 } else if (IDecl->getStorageClass() == VarDecl::Extern) { 2218 Diag(IDecl->getLocation(), diag::err_vla_decl_has_extern_linkage) 2219 << SizeRange; 2220 IDecl->setInvalidDecl(); 2221 } 2222 } 2223 } else if (T->isVariablyModifiedType()) { 2224 if (IDecl->isFileVarDecl()) { 2225 Diag(IDecl->getLocation(), diag::err_vm_decl_in_file_scope); 2226 IDecl->setInvalidDecl(); 2227 } else { 2228 if (IDecl->getStorageClass() == VarDecl::Extern) { 2229 Diag(IDecl->getLocation(), diag::err_vm_decl_has_extern_linkage); 2230 IDecl->setInvalidDecl(); 2231 } 2232 } 2233 } 2234 2235 // Block scope. C99 6.7p7: If an identifier for an object is declared with 2236 // no linkage (C99 6.2.2p6), the type for the object shall be complete... 2237 if (IDecl->isBlockVarDecl() && 2238 IDecl->getStorageClass() != VarDecl::Extern) { 2239 if (T->isIncompleteType() && !IDecl->isInvalidDecl()) { 2240 Diag(IDecl->getLocation(), diag::err_typecheck_decl_incomplete_type)<<T; 2241 IDecl->setInvalidDecl(); 2242 } 2243 } 2244 // File scope. C99 6.9.2p2: A declaration of an identifier for and 2245 // object that has file scope without an initializer, and without a 2246 // storage-class specifier or with the storage-class specifier "static", 2247 // constitutes a tentative definition. Note: A tentative definition with 2248 // external linkage is valid (C99 6.2.2p5). 2249 if (isTentativeDefinition(IDecl)) { 2250 if (T->isIncompleteArrayType()) { 2251 // C99 6.9.2 (p2, p5): Implicit initialization causes an incomplete 2252 // array to be completed. Don't issue a diagnostic. 2253 } else if (T->isIncompleteType() && !IDecl->isInvalidDecl()) { 2254 // C99 6.9.2p3: If the declaration of an identifier for an object is 2255 // a tentative definition and has internal linkage (C99 6.2.2p3), the 2256 // declared type shall not be an incomplete type. 2257 Diag(IDecl->getLocation(), diag::err_typecheck_decl_incomplete_type)<<T; 2258 IDecl->setInvalidDecl(); 2259 } 2260 } 2261 if (IDecl->isFileVarDecl()) 2262 CheckForFileScopedRedefinitions(S, IDecl); 2263 } 2264 return NewGroup; 2265} 2266 2267/// ActOnParamDeclarator - Called from Parser::ParseFunctionDeclarator() 2268/// to introduce parameters into function prototype scope. 2269Sema::DeclTy * 2270Sema::ActOnParamDeclarator(Scope *S, Declarator &D) { 2271 const DeclSpec &DS = D.getDeclSpec(); 2272 2273 // Verify C99 6.7.5.3p2: The only SCS allowed is 'register'. 2274 VarDecl::StorageClass StorageClass = VarDecl::None; 2275 if (DS.getStorageClassSpec() == DeclSpec::SCS_register) { 2276 StorageClass = VarDecl::Register; 2277 } else if (DS.getStorageClassSpec() != DeclSpec::SCS_unspecified) { 2278 Diag(DS.getStorageClassSpecLoc(), 2279 diag::err_invalid_storage_class_in_func_decl); 2280 D.getMutableDeclSpec().ClearStorageClassSpecs(); 2281 } 2282 if (DS.isThreadSpecified()) { 2283 Diag(DS.getThreadSpecLoc(), 2284 diag::err_invalid_storage_class_in_func_decl); 2285 D.getMutableDeclSpec().ClearStorageClassSpecs(); 2286 } 2287 2288 // Check that there are no default arguments inside the type of this 2289 // parameter (C++ only). 2290 if (getLangOptions().CPlusPlus) 2291 CheckExtraCXXDefaultArguments(D); 2292 2293 // In this context, we *do not* check D.getInvalidType(). If the declarator 2294 // type was invalid, GetTypeForDeclarator() still returns a "valid" type, 2295 // though it will not reflect the user specified type. 2296 QualType parmDeclType = GetTypeForDeclarator(D, S); 2297 2298 assert(!parmDeclType.isNull() && "GetTypeForDeclarator() returned null type"); 2299 2300 // TODO: CHECK FOR CONFLICTS, multiple decls with same name in one scope. 2301 // Can this happen for params? We already checked that they don't conflict 2302 // among each other. Here they can only shadow globals, which is ok. 2303 IdentifierInfo *II = D.getIdentifier(); 2304 if (Decl *PrevDecl = LookupDecl(II, Decl::IDNS_Ordinary, S)) { 2305 if (PrevDecl->isTemplateParameter()) { 2306 // Maybe we will complain about the shadowed template parameter. 2307 DiagnoseTemplateParameterShadow(D.getIdentifierLoc(), PrevDecl); 2308 // Just pretend that we didn't see the previous declaration. 2309 PrevDecl = 0; 2310 } else if (S->isDeclScope(PrevDecl)) { 2311 Diag(D.getIdentifierLoc(), diag::err_param_redefinition) << II; 2312 2313 // Recover by removing the name 2314 II = 0; 2315 D.SetIdentifier(0, D.getIdentifierLoc()); 2316 } 2317 } 2318 2319 // Perform the default function/array conversion (C99 6.7.5.3p[7,8]). 2320 // Doing the promotion here has a win and a loss. The win is the type for 2321 // both Decl's and DeclRefExpr's will match (a convenient invariant for the 2322 // code generator). The loss is the orginal type isn't preserved. For example: 2323 // 2324 // void func(int parmvardecl[5]) { // convert "int [5]" to "int *" 2325 // int blockvardecl[5]; 2326 // sizeof(parmvardecl); // size == 4 2327 // sizeof(blockvardecl); // size == 20 2328 // } 2329 // 2330 // For expressions, all implicit conversions are captured using the 2331 // ImplicitCastExpr AST node (we have no such mechanism for Decl's). 2332 // 2333 // FIXME: If a source translation tool needs to see the original type, then 2334 // we need to consider storing both types (in ParmVarDecl)... 2335 // 2336 if (parmDeclType->isArrayType()) { 2337 // int x[restrict 4] -> int *restrict 2338 parmDeclType = Context.getArrayDecayedType(parmDeclType); 2339 } else if (parmDeclType->isFunctionType()) 2340 parmDeclType = Context.getPointerType(parmDeclType); 2341 2342 ParmVarDecl *New = ParmVarDecl::Create(Context, CurContext, 2343 D.getIdentifierLoc(), II, 2344 parmDeclType, StorageClass, 2345 0, 0); 2346 2347 if (D.getInvalidType()) 2348 New->setInvalidDecl(); 2349 2350 // Parameter declarators cannot be qualified (C++ [dcl.meaning]p1). 2351 if (D.getCXXScopeSpec().isSet()) { 2352 Diag(D.getIdentifierLoc(), diag::err_qualified_param_declarator) 2353 << D.getCXXScopeSpec().getRange(); 2354 New->setInvalidDecl(); 2355 } 2356 2357 // Add the parameter declaration into this scope. 2358 S->AddDecl(New); 2359 if (II) 2360 IdResolver.AddDecl(New); 2361 2362 ProcessDeclAttributes(New, D); 2363 return New; 2364 2365} 2366 2367Sema::DeclTy *Sema::ActOnStartOfFunctionDef(Scope *FnBodyScope, Declarator &D) { 2368 assert(getCurFunctionDecl() == 0 && "Function parsing confused"); 2369 assert(D.getTypeObject(0).Kind == DeclaratorChunk::Function && 2370 "Not a function declarator!"); 2371 DeclaratorChunk::FunctionTypeInfo &FTI = D.getTypeObject(0).Fun; 2372 2373 // Verify 6.9.1p6: 'every identifier in the identifier list shall be declared' 2374 // for a K&R function. 2375 if (!FTI.hasPrototype) { 2376 for (unsigned i = 0, e = FTI.NumArgs; i != e; ++i) { 2377 if (FTI.ArgInfo[i].Param == 0) { 2378 Diag(FTI.ArgInfo[i].IdentLoc, diag::ext_param_not_declared) 2379 << FTI.ArgInfo[i].Ident; 2380 // Implicitly declare the argument as type 'int' for lack of a better 2381 // type. 2382 DeclSpec DS; 2383 const char* PrevSpec; // unused 2384 DS.SetTypeSpecType(DeclSpec::TST_int, FTI.ArgInfo[i].IdentLoc, 2385 PrevSpec); 2386 Declarator ParamD(DS, Declarator::KNRTypeListContext); 2387 ParamD.SetIdentifier(FTI.ArgInfo[i].Ident, FTI.ArgInfo[i].IdentLoc); 2388 FTI.ArgInfo[i].Param = ActOnParamDeclarator(FnBodyScope, ParamD); 2389 } 2390 } 2391 } else { 2392 // FIXME: Diagnose arguments without names in C. 2393 } 2394 2395 Scope *ParentScope = FnBodyScope->getParent(); 2396 2397 return ActOnStartOfFunctionDef(FnBodyScope, 2398 ActOnDeclarator(ParentScope, D, 0, 2399 /*IsFunctionDefinition=*/true)); 2400} 2401 2402Sema::DeclTy *Sema::ActOnStartOfFunctionDef(Scope *FnBodyScope, DeclTy *D) { 2403 Decl *decl = static_cast<Decl*>(D); 2404 FunctionDecl *FD = cast<FunctionDecl>(decl); 2405 2406 // See if this is a redefinition. 2407 const FunctionDecl *Definition; 2408 if (FD->getBody(Definition)) { 2409 Diag(FD->getLocation(), diag::err_redefinition) << FD->getDeclName(); 2410 Diag(Definition->getLocation(), diag::note_previous_definition); 2411 } 2412 2413 PushDeclContext(FnBodyScope, FD); 2414 2415 // Check the validity of our function parameters 2416 CheckParmsForFunctionDef(FD); 2417 2418 // Introduce our parameters into the function scope 2419 for (unsigned p = 0, NumParams = FD->getNumParams(); p < NumParams; ++p) { 2420 ParmVarDecl *Param = FD->getParamDecl(p); 2421 // If this has an identifier, add it to the scope stack. 2422 if (Param->getIdentifier()) 2423 PushOnScopeChains(Param, FnBodyScope); 2424 } 2425 2426 // Checking attributes of current function definition 2427 // dllimport attribute. 2428 if (FD->getAttr<DLLImportAttr>() && (!FD->getAttr<DLLExportAttr>())) { 2429 // dllimport attribute cannot be applied to definition. 2430 if (!(FD->getAttr<DLLImportAttr>())->isInherited()) { 2431 Diag(FD->getLocation(), 2432 diag::err_attribute_can_be_applied_only_to_symbol_declaration) 2433 << "dllimport"; 2434 FD->setInvalidDecl(); 2435 return FD; 2436 } else { 2437 // If a symbol previously declared dllimport is later defined, the 2438 // attribute is ignored in subsequent references, and a warning is 2439 // emitted. 2440 Diag(FD->getLocation(), 2441 diag::warn_redeclaration_without_attribute_prev_attribute_ignored) 2442 << FD->getNameAsCString() << "dllimport"; 2443 } 2444 } 2445 return FD; 2446} 2447 2448Sema::DeclTy *Sema::ActOnFinishFunctionBody(DeclTy *D, StmtArg BodyArg) { 2449 Decl *dcl = static_cast<Decl *>(D); 2450 Stmt *Body = static_cast<Stmt*>(BodyArg.release()); 2451 if (FunctionDecl *FD = dyn_cast_or_null<FunctionDecl>(dcl)) { 2452 FD->setBody(Body); 2453 assert(FD == getCurFunctionDecl() && "Function parsing confused"); 2454 } else if (ObjCMethodDecl *MD = dyn_cast_or_null<ObjCMethodDecl>(dcl)) { 2455 MD->setBody((Stmt*)Body); 2456 } else 2457 return 0; 2458 PopDeclContext(); 2459 // Verify and clean out per-function state. 2460 2461 // Check goto/label use. 2462 for (llvm::DenseMap<IdentifierInfo*, LabelStmt*>::iterator 2463 I = LabelMap.begin(), E = LabelMap.end(); I != E; ++I) { 2464 // Verify that we have no forward references left. If so, there was a goto 2465 // or address of a label taken, but no definition of it. Label fwd 2466 // definitions are indicated with a null substmt. 2467 if (I->second->getSubStmt() == 0) { 2468 LabelStmt *L = I->second; 2469 // Emit error. 2470 Diag(L->getIdentLoc(), diag::err_undeclared_label_use) << L->getName(); 2471 2472 // At this point, we have gotos that use the bogus label. Stitch it into 2473 // the function body so that they aren't leaked and that the AST is well 2474 // formed. 2475 if (Body) { 2476 L->setSubStmt(new NullStmt(L->getIdentLoc())); 2477 cast<CompoundStmt>(Body)->push_back(L); 2478 } else { 2479 // The whole function wasn't parsed correctly, just delete this. 2480 delete L; 2481 } 2482 } 2483 } 2484 LabelMap.clear(); 2485 2486 return D; 2487} 2488 2489/// ImplicitlyDefineFunction - An undeclared identifier was used in a function 2490/// call, forming a call to an implicitly defined function (per C99 6.5.1p2). 2491ScopedDecl *Sema::ImplicitlyDefineFunction(SourceLocation Loc, 2492 IdentifierInfo &II, Scope *S) { 2493 // Extension in C99. Legal in C90, but warn about it. 2494 if (getLangOptions().C99) 2495 Diag(Loc, diag::ext_implicit_function_decl) << &II; 2496 else 2497 Diag(Loc, diag::warn_implicit_function_decl) << &II; 2498 2499 // FIXME: handle stuff like: 2500 // void foo() { extern float X(); } 2501 // void bar() { X(); } <-- implicit decl for X in another scope. 2502 2503 // Set a Declarator for the implicit definition: int foo(); 2504 const char *Dummy; 2505 DeclSpec DS; 2506 bool Error = DS.SetTypeSpecType(DeclSpec::TST_int, Loc, Dummy); 2507 Error = Error; // Silence warning. 2508 assert(!Error && "Error setting up implicit decl!"); 2509 Declarator D(DS, Declarator::BlockContext); 2510 D.AddTypeInfo(DeclaratorChunk::getFunction(false, false, 0, 0, 0, Loc)); 2511 D.SetIdentifier(&II, Loc); 2512 2513 // Insert this function into translation-unit scope. 2514 2515 DeclContext *PrevDC = CurContext; 2516 CurContext = Context.getTranslationUnitDecl(); 2517 2518 FunctionDecl *FD = 2519 dyn_cast<FunctionDecl>(static_cast<Decl*>(ActOnDeclarator(TUScope, D, 0))); 2520 FD->setImplicit(); 2521 2522 CurContext = PrevDC; 2523 2524 return FD; 2525} 2526 2527 2528TypedefDecl *Sema::ParseTypedefDecl(Scope *S, Declarator &D, QualType T, 2529 ScopedDecl *LastDeclarator) { 2530 assert(D.getIdentifier() && "Wrong callback for declspec without declarator"); 2531 assert(!T.isNull() && "GetTypeForDeclarator() returned null type"); 2532 2533 // Scope manipulation handled by caller. 2534 TypedefDecl *NewTD = TypedefDecl::Create(Context, CurContext, 2535 D.getIdentifierLoc(), 2536 D.getIdentifier(), 2537 T, LastDeclarator); 2538 if (D.getInvalidType()) 2539 NewTD->setInvalidDecl(); 2540 return NewTD; 2541} 2542 2543/// ActOnTag - This is invoked when we see 'struct foo' or 'struct {'. In the 2544/// former case, Name will be non-null. In the later case, Name will be null. 2545/// TagType indicates what kind of tag this is. TK indicates whether this is a 2546/// reference/declaration/definition of a tag. 2547Sema::DeclTy *Sema::ActOnTag(Scope *S, unsigned TagType, TagKind TK, 2548 SourceLocation KWLoc, const CXXScopeSpec &SS, 2549 IdentifierInfo *Name, SourceLocation NameLoc, 2550 AttributeList *Attr, 2551 MultiTemplateParamsArg TemplateParameterLists) { 2552 // If this is not a definition, it must have a name. 2553 assert((Name != 0 || TK == TK_Definition) && 2554 "Nameless record must be a definition!"); 2555 2556 TagDecl::TagKind Kind; 2557 switch (TagType) { 2558 default: assert(0 && "Unknown tag type!"); 2559 case DeclSpec::TST_struct: Kind = TagDecl::TK_struct; break; 2560 case DeclSpec::TST_union: Kind = TagDecl::TK_union; break; 2561 case DeclSpec::TST_class: Kind = TagDecl::TK_class; break; 2562 case DeclSpec::TST_enum: Kind = TagDecl::TK_enum; break; 2563 } 2564 2565 DeclContext *DC = CurContext; 2566 ScopedDecl *PrevDecl = 0; 2567 2568 if (Name && SS.isNotEmpty()) { 2569 // We have a nested-name tag ('struct foo::bar'). 2570 2571 // Check for invalid 'foo::'. 2572 if (SS.isInvalid()) { 2573 Name = 0; 2574 goto CreateNewDecl; 2575 } 2576 2577 DC = static_cast<DeclContext*>(SS.getScopeRep()); 2578 // Look-up name inside 'foo::'. 2579 PrevDecl = dyn_cast_or_null<TagDecl>(LookupDecl(Name, Decl::IDNS_Tag,S,DC)); 2580 2581 // A tag 'foo::bar' must already exist. 2582 if (PrevDecl == 0) { 2583 Diag(NameLoc, diag::err_not_tag_in_scope) << Name << SS.getRange(); 2584 Name = 0; 2585 goto CreateNewDecl; 2586 } 2587 } else { 2588 // If this is a named struct, check to see if there was a previous forward 2589 // declaration or definition. 2590 // Use ScopedDecl instead of TagDecl, because a NamespaceDecl may come up. 2591 PrevDecl = dyn_cast_or_null<ScopedDecl>(LookupDecl(Name, Decl::IDNS_Tag,S)); 2592 } 2593 2594 if (PrevDecl && PrevDecl->isTemplateParameter()) { 2595 // Maybe we will complain about the shadowed template parameter. 2596 DiagnoseTemplateParameterShadow(NameLoc, PrevDecl); 2597 // Just pretend that we didn't see the previous declaration. 2598 PrevDecl = 0; 2599 } 2600 2601 if (PrevDecl) { 2602 assert((isa<TagDecl>(PrevDecl) || isa<NamespaceDecl>(PrevDecl)) && 2603 "unexpected Decl type"); 2604 if (TagDecl *PrevTagDecl = dyn_cast<TagDecl>(PrevDecl)) { 2605 // If this is a use of a previous tag, or if the tag is already declared 2606 // in the same scope (so that the definition/declaration completes or 2607 // rementions the tag), reuse the decl. 2608 if (TK == TK_Reference || isDeclInScope(PrevDecl, DC, S)) { 2609 // Make sure that this wasn't declared as an enum and now used as a 2610 // struct or something similar. 2611 if (PrevTagDecl->getTagKind() != Kind) { 2612 Diag(KWLoc, diag::err_use_with_wrong_tag) << Name; 2613 Diag(PrevDecl->getLocation(), diag::note_previous_use); 2614 // Recover by making this an anonymous redefinition. 2615 Name = 0; 2616 PrevDecl = 0; 2617 } else { 2618 // If this is a use, just return the declaration we found. 2619 2620 // FIXME: In the future, return a variant or some other clue 2621 // for the consumer of this Decl to know it doesn't own it. 2622 // For our current ASTs this shouldn't be a problem, but will 2623 // need to be changed with DeclGroups. 2624 if (TK == TK_Reference) 2625 return PrevDecl; 2626 2627 // Diagnose attempts to redefine a tag. 2628 if (TK == TK_Definition) { 2629 if (TagDecl *Def = PrevTagDecl->getDefinition(Context)) { 2630 Diag(NameLoc, diag::err_redefinition) << Name; 2631 Diag(Def->getLocation(), diag::note_previous_definition); 2632 // If this is a redefinition, recover by making this struct be 2633 // anonymous, which will make any later references get the previous 2634 // definition. 2635 Name = 0; 2636 PrevDecl = 0; 2637 } 2638 // Okay, this is definition of a previously declared or referenced 2639 // tag PrevDecl. We're going to create a new Decl for it. 2640 } 2641 } 2642 // If we get here we have (another) forward declaration or we 2643 // have a definition. Just create a new decl. 2644 } else { 2645 // If we get here, this is a definition of a new tag type in a nested 2646 // scope, e.g. "struct foo; void bar() { struct foo; }", just create a 2647 // new decl/type. We set PrevDecl to NULL so that the entities 2648 // have distinct types. 2649 PrevDecl = 0; 2650 } 2651 // If we get here, we're going to create a new Decl. If PrevDecl 2652 // is non-NULL, it's a definition of the tag declared by 2653 // PrevDecl. If it's NULL, we have a new definition. 2654 } else { 2655 // PrevDecl is a namespace. 2656 if (isDeclInScope(PrevDecl, DC, S)) { 2657 // The tag name clashes with a namespace name, issue an error and 2658 // recover by making this tag be anonymous. 2659 Diag(NameLoc, diag::err_redefinition_different_kind) << Name; 2660 Diag(PrevDecl->getLocation(), diag::note_previous_definition); 2661 Name = 0; 2662 PrevDecl = 0; 2663 } else { 2664 // The existing declaration isn't relevant to us; we're in a 2665 // new scope, so clear out the previous declaration. 2666 PrevDecl = 0; 2667 } 2668 } 2669 } 2670 2671CreateNewDecl: 2672 2673 // If there is an identifier, use the location of the identifier as the 2674 // location of the decl, otherwise use the location of the struct/union 2675 // keyword. 2676 SourceLocation Loc = NameLoc.isValid() ? NameLoc : KWLoc; 2677 2678 // Otherwise, create a new declaration. If there is a previous 2679 // declaration of the same entity, the two will be linked via 2680 // PrevDecl. 2681 TagDecl *New; 2682 if (Kind == TagDecl::TK_enum) { 2683 // FIXME: Tag decls should be chained to any simultaneous vardecls, e.g.: 2684 // enum X { A, B, C } D; D should chain to X. 2685 New = EnumDecl::Create(Context, DC, Loc, Name, 2686 cast_or_null<EnumDecl>(PrevDecl)); 2687 // If this is an undefined enum, warn. 2688 if (TK != TK_Definition) Diag(Loc, diag::ext_forward_ref_enum); 2689 } else { 2690 // struct/union/class 2691 2692 // FIXME: Tag decls should be chained to any simultaneous vardecls, e.g.: 2693 // struct X { int A; } D; D should chain to X. 2694 if (getLangOptions().CPlusPlus) 2695 // FIXME: Look for a way to use RecordDecl for simple structs. 2696 New = CXXRecordDecl::Create(Context, Kind, DC, Loc, Name, 2697 cast_or_null<CXXRecordDecl>(PrevDecl)); 2698 else 2699 New = RecordDecl::Create(Context, Kind, DC, Loc, Name, 2700 cast_or_null<RecordDecl>(PrevDecl)); 2701 } 2702 2703 if (Kind != TagDecl::TK_enum) { 2704 // Handle #pragma pack: if the #pragma pack stack has non-default 2705 // alignment, make up a packed attribute for this decl. These 2706 // attributes are checked when the ASTContext lays out the 2707 // structure. 2708 // 2709 // It is important for implementing the correct semantics that this 2710 // happen here (in act on tag decl). The #pragma pack stack is 2711 // maintained as a result of parser callbacks which can occur at 2712 // many points during the parsing of a struct declaration (because 2713 // the #pragma tokens are effectively skipped over during the 2714 // parsing of the struct). 2715 if (unsigned Alignment = PackContext.getAlignment()) 2716 New->addAttr(new PackedAttr(Alignment * 8)); 2717 } 2718 2719 if (Attr) 2720 ProcessDeclAttributeList(New, Attr); 2721 2722 // Set the lexical context. If the tag has a C++ scope specifier, the 2723 // lexical context will be different from the semantic context. 2724 New->setLexicalDeclContext(CurContext); 2725 2726 // If this has an identifier, add it to the scope stack. 2727 if (Name) { 2728 // The scope passed in may not be a decl scope. Zip up the scope tree until 2729 // we find one that is. 2730 while ((S->getFlags() & Scope::DeclScope) == 0) 2731 S = S->getParent(); 2732 2733 // Add it to the decl chain. 2734 PushOnScopeChains(New, S); 2735 } 2736 2737 return New; 2738} 2739 2740 2741/// TryToFixInvalidVariablyModifiedType - Helper method to turn variable array 2742/// types into constant array types in certain situations which would otherwise 2743/// be errors (for GCC compatibility). 2744static QualType TryToFixInvalidVariablyModifiedType(QualType T, 2745 ASTContext &Context) { 2746 // This method tries to turn a variable array into a constant 2747 // array even when the size isn't an ICE. This is necessary 2748 // for compatibility with code that depends on gcc's buggy 2749 // constant expression folding, like struct {char x[(int)(char*)2];} 2750 const VariableArrayType* VLATy = dyn_cast<VariableArrayType>(T); 2751 if (!VLATy) return QualType(); 2752 2753 Expr::EvalResult EvalResult; 2754 if (!VLATy->getSizeExpr() || 2755 !VLATy->getSizeExpr()->Evaluate(EvalResult, Context)) 2756 return QualType(); 2757 2758 assert(EvalResult.Val.isInt() && "Size expressions must be integers!"); 2759 llvm::APSInt &Res = EvalResult.Val.getInt(); 2760 if (Res > llvm::APSInt(Res.getBitWidth(), Res.isUnsigned())) 2761 return Context.getConstantArrayType(VLATy->getElementType(), 2762 Res, ArrayType::Normal, 0); 2763 return QualType(); 2764} 2765 2766bool Sema::VerifyBitField(SourceLocation FieldLoc, IdentifierInfo *FieldName, 2767 QualType FieldTy, const Expr *BitWidth) { 2768 // FIXME: 6.7.2.1p4 - verify the field type. 2769 2770 llvm::APSInt Value; 2771 if (VerifyIntegerConstantExpression(BitWidth, &Value)) 2772 return true; 2773 2774 // Zero-width bitfield is ok for anonymous field. 2775 if (Value == 0 && FieldName) 2776 return Diag(FieldLoc, diag::err_bitfield_has_zero_width) << FieldName; 2777 2778 if (Value.isNegative()) 2779 return Diag(FieldLoc, diag::err_bitfield_has_negative_width) << FieldName; 2780 2781 uint64_t TypeSize = Context.getTypeSize(FieldTy); 2782 // FIXME: We won't need the 0 size once we check that the field type is valid. 2783 if (TypeSize && Value.getZExtValue() > TypeSize) 2784 return Diag(FieldLoc, diag::err_bitfield_width_exceeds_type_size) 2785 << FieldName << (unsigned)TypeSize; 2786 2787 return false; 2788} 2789 2790/// ActOnField - Each field of a struct/union/class is passed into this in order 2791/// to create a FieldDecl object for it. 2792Sema::DeclTy *Sema::ActOnField(Scope *S, DeclTy *TagD, 2793 SourceLocation DeclStart, 2794 Declarator &D, ExprTy *BitfieldWidth) { 2795 IdentifierInfo *II = D.getIdentifier(); 2796 Expr *BitWidth = (Expr*)BitfieldWidth; 2797 SourceLocation Loc = DeclStart; 2798 RecordDecl *Record = (RecordDecl *)TagD; 2799 if (II) Loc = D.getIdentifierLoc(); 2800 2801 // FIXME: Unnamed fields can be handled in various different ways, for 2802 // example, unnamed unions inject all members into the struct namespace! 2803 2804 QualType T = GetTypeForDeclarator(D, S); 2805 assert(!T.isNull() && "GetTypeForDeclarator() returned null type"); 2806 bool InvalidDecl = false; 2807 2808 // C99 6.7.2.1p8: A member of a structure or union may have any type other 2809 // than a variably modified type. 2810 if (T->isVariablyModifiedType()) { 2811 QualType FixedTy = TryToFixInvalidVariablyModifiedType(T, Context); 2812 if (!FixedTy.isNull()) { 2813 Diag(Loc, diag::warn_illegal_constant_array_size); 2814 T = FixedTy; 2815 } else { 2816 Diag(Loc, diag::err_typecheck_field_variable_size); 2817 T = Context.IntTy; 2818 InvalidDecl = true; 2819 } 2820 } 2821 2822 if (BitWidth) { 2823 if (VerifyBitField(Loc, II, T, BitWidth)) 2824 InvalidDecl = true; 2825 } else { 2826 // Not a bitfield. 2827 2828 // validate II. 2829 2830 } 2831 2832 // FIXME: Chain fielddecls together. 2833 FieldDecl *NewFD; 2834 2835 // FIXME: We don't want CurContext for C, do we? No, we'll need some 2836 // other way to determine the current RecordDecl. 2837 NewFD = FieldDecl::Create(Context, Record, 2838 Loc, II, T, BitWidth, 2839 D.getDeclSpec().getStorageClassSpec() == 2840 DeclSpec::SCS_mutable, 2841 /*PrevDecl=*/0); 2842 2843 if (getLangOptions().CPlusPlus) 2844 CheckExtraCXXDefaultArguments(D); 2845 2846 ProcessDeclAttributes(NewFD, D); 2847 2848 if (D.getInvalidType() || InvalidDecl) 2849 NewFD->setInvalidDecl(); 2850 2851 if (II && getLangOptions().CPlusPlus) 2852 PushOnScopeChains(NewFD, S); 2853 else 2854 Record->addDecl(Context, NewFD); 2855 2856 return NewFD; 2857} 2858 2859/// TranslateIvarVisibility - Translate visibility from a token ID to an 2860/// AST enum value. 2861static ObjCIvarDecl::AccessControl 2862TranslateIvarVisibility(tok::ObjCKeywordKind ivarVisibility) { 2863 switch (ivarVisibility) { 2864 default: assert(0 && "Unknown visitibility kind"); 2865 case tok::objc_private: return ObjCIvarDecl::Private; 2866 case tok::objc_public: return ObjCIvarDecl::Public; 2867 case tok::objc_protected: return ObjCIvarDecl::Protected; 2868 case tok::objc_package: return ObjCIvarDecl::Package; 2869 } 2870} 2871 2872/// ActOnIvar - Each ivar field of an objective-c class is passed into this 2873/// in order to create an IvarDecl object for it. 2874Sema::DeclTy *Sema::ActOnIvar(Scope *S, 2875 SourceLocation DeclStart, 2876 Declarator &D, ExprTy *BitfieldWidth, 2877 tok::ObjCKeywordKind Visibility) { 2878 IdentifierInfo *II = D.getIdentifier(); 2879 Expr *BitWidth = (Expr*)BitfieldWidth; 2880 SourceLocation Loc = DeclStart; 2881 if (II) Loc = D.getIdentifierLoc(); 2882 2883 // FIXME: Unnamed fields can be handled in various different ways, for 2884 // example, unnamed unions inject all members into the struct namespace! 2885 2886 QualType T = GetTypeForDeclarator(D, S); 2887 assert(!T.isNull() && "GetTypeForDeclarator() returned null type"); 2888 bool InvalidDecl = false; 2889 2890 if (BitWidth) { 2891 // TODO: Validate. 2892 //printf("WARNING: BITFIELDS IGNORED!\n"); 2893 2894 // 6.7.2.1p3 2895 // 6.7.2.1p4 2896 2897 } else { 2898 // Not a bitfield. 2899 2900 // validate II. 2901 2902 } 2903 2904 // C99 6.7.2.1p8: A member of a structure or union may have any type other 2905 // than a variably modified type. 2906 if (T->isVariablyModifiedType()) { 2907 Diag(Loc, diag::err_typecheck_ivar_variable_size); 2908 InvalidDecl = true; 2909 } 2910 2911 // Get the visibility (access control) for this ivar. 2912 ObjCIvarDecl::AccessControl ac = 2913 Visibility != tok::objc_not_keyword ? TranslateIvarVisibility(Visibility) 2914 : ObjCIvarDecl::None; 2915 2916 // Construct the decl. 2917 ObjCIvarDecl *NewID = ObjCIvarDecl::Create(Context, Loc, II, T, ac, 2918 (Expr *)BitfieldWidth); 2919 2920 // Process attributes attached to the ivar. 2921 ProcessDeclAttributes(NewID, D); 2922 2923 if (D.getInvalidType() || InvalidDecl) 2924 NewID->setInvalidDecl(); 2925 2926 return NewID; 2927} 2928 2929void Sema::ActOnFields(Scope* S, 2930 SourceLocation RecLoc, DeclTy *RecDecl, 2931 DeclTy **Fields, unsigned NumFields, 2932 SourceLocation LBrac, SourceLocation RBrac, 2933 AttributeList *Attr) { 2934 Decl *EnclosingDecl = static_cast<Decl*>(RecDecl); 2935 assert(EnclosingDecl && "missing record or interface decl"); 2936 RecordDecl *Record = dyn_cast<RecordDecl>(EnclosingDecl); 2937 2938 if (Record) 2939 if (RecordDecl* DefRecord = Record->getDefinition(Context)) { 2940 // Diagnose code like: 2941 // struct S { struct S {} X; }; 2942 // We discover this when we complete the outer S. Reject and ignore the 2943 // outer S. 2944 Diag(DefRecord->getLocation(), diag::err_nested_redefinition) 2945 << DefRecord->getDeclName(); 2946 Diag(RecLoc, diag::note_previous_definition); 2947 Record->setInvalidDecl(); 2948 return; 2949 } 2950 2951 // Verify that all the fields are okay. 2952 unsigned NumNamedMembers = 0; 2953 llvm::SmallVector<FieldDecl*, 32> RecFields; 2954 llvm::SmallSet<const IdentifierInfo*, 32> FieldIDs; 2955 2956 for (unsigned i = 0; i != NumFields; ++i) { 2957 2958 FieldDecl *FD = cast_or_null<FieldDecl>(static_cast<Decl*>(Fields[i])); 2959 assert(FD && "missing field decl"); 2960 2961 // Remember all fields. 2962 RecFields.push_back(FD); 2963 2964 // Get the type for the field. 2965 Type *FDTy = FD->getType().getTypePtr(); 2966 2967 // C99 6.7.2.1p2 - A field may not be a function type. 2968 if (FDTy->isFunctionType()) { 2969 Diag(FD->getLocation(), diag::err_field_declared_as_function) 2970 << FD->getDeclName(); 2971 FD->setInvalidDecl(); 2972 EnclosingDecl->setInvalidDecl(); 2973 continue; 2974 } 2975 // C99 6.7.2.1p2 - A field may not be an incomplete type except... 2976 if (FDTy->isIncompleteType()) { 2977 if (!Record) { // Incomplete ivar type is always an error. 2978 Diag(FD->getLocation(), diag::err_field_incomplete) <<FD->getDeclName(); 2979 FD->setInvalidDecl(); 2980 EnclosingDecl->setInvalidDecl(); 2981 continue; 2982 } 2983 if (i != NumFields-1 || // ... that the last member ... 2984 !Record->isStruct() || // ... of a structure ... 2985 !FDTy->isArrayType()) { //... may have incomplete array type. 2986 Diag(FD->getLocation(), diag::err_field_incomplete) <<FD->getDeclName(); 2987 FD->setInvalidDecl(); 2988 EnclosingDecl->setInvalidDecl(); 2989 continue; 2990 } 2991 if (NumNamedMembers < 1) { //... must have more than named member ... 2992 Diag(FD->getLocation(), diag::err_flexible_array_empty_struct) 2993 << FD->getDeclName(); 2994 FD->setInvalidDecl(); 2995 EnclosingDecl->setInvalidDecl(); 2996 continue; 2997 } 2998 // Okay, we have a legal flexible array member at the end of the struct. 2999 if (Record) 3000 Record->setHasFlexibleArrayMember(true); 3001 } 3002 /// C99 6.7.2.1p2 - a struct ending in a flexible array member cannot be the 3003 /// field of another structure or the element of an array. 3004 if (const RecordType *FDTTy = FDTy->getAsRecordType()) { 3005 if (FDTTy->getDecl()->hasFlexibleArrayMember()) { 3006 // If this is a member of a union, then entire union becomes "flexible". 3007 if (Record && Record->isUnion()) { 3008 Record->setHasFlexibleArrayMember(true); 3009 } else { 3010 // If this is a struct/class and this is not the last element, reject 3011 // it. Note that GCC supports variable sized arrays in the middle of 3012 // structures. 3013 if (i != NumFields-1) { 3014 Diag(FD->getLocation(), diag::err_variable_sized_type_in_struct) 3015 << FD->getDeclName(); 3016 FD->setInvalidDecl(); 3017 EnclosingDecl->setInvalidDecl(); 3018 continue; 3019 } 3020 // We support flexible arrays at the end of structs in other structs 3021 // as an extension. 3022 Diag(FD->getLocation(), diag::ext_flexible_array_in_struct) 3023 << FD->getDeclName(); 3024 if (Record) 3025 Record->setHasFlexibleArrayMember(true); 3026 } 3027 } 3028 } 3029 /// A field cannot be an Objective-c object 3030 if (FDTy->isObjCInterfaceType()) { 3031 Diag(FD->getLocation(), diag::err_statically_allocated_object) 3032 << FD->getDeclName(); 3033 FD->setInvalidDecl(); 3034 EnclosingDecl->setInvalidDecl(); 3035 continue; 3036 } 3037 // Keep track of the number of named members. 3038 if (IdentifierInfo *II = FD->getIdentifier()) { 3039 // Detect duplicate member names. 3040 if (!FieldIDs.insert(II)) { 3041 Diag(FD->getLocation(), diag::err_duplicate_member) << II; 3042 // Find the previous decl. 3043 SourceLocation PrevLoc; 3044 for (unsigned i = 0; ; ++i) { 3045 assert(i != RecFields.size() && "Didn't find previous def!"); 3046 if (RecFields[i]->getIdentifier() == II) { 3047 PrevLoc = RecFields[i]->getLocation(); 3048 break; 3049 } 3050 } 3051 Diag(PrevLoc, diag::note_previous_definition); 3052 FD->setInvalidDecl(); 3053 EnclosingDecl->setInvalidDecl(); 3054 continue; 3055 } 3056 ++NumNamedMembers; 3057 } 3058 } 3059 3060 // Okay, we successfully defined 'Record'. 3061 if (Record) { 3062 Record->completeDefinition(Context); 3063 // If this is a C++ record, HandleTagDeclDefinition will be invoked in 3064 // Sema::ActOnFinishCXXClassDef. 3065 if (!isa<CXXRecordDecl>(Record)) 3066 Consumer.HandleTagDeclDefinition(Record); 3067 } else { 3068 ObjCIvarDecl **ClsFields = reinterpret_cast<ObjCIvarDecl**>(&RecFields[0]); 3069 if (ObjCInterfaceDecl *ID = dyn_cast<ObjCInterfaceDecl>(EnclosingDecl)) { 3070 ID->addInstanceVariablesToClass(ClsFields, RecFields.size(), RBrac); 3071 // Must enforce the rule that ivars in the base classes may not be 3072 // duplicates. 3073 if (ID->getSuperClass()) { 3074 for (ObjCInterfaceDecl::ivar_iterator IVI = ID->ivar_begin(), 3075 IVE = ID->ivar_end(); IVI != IVE; ++IVI) { 3076 ObjCIvarDecl* Ivar = (*IVI); 3077 IdentifierInfo *II = Ivar->getIdentifier(); 3078 ObjCIvarDecl* prevIvar = ID->getSuperClass()->FindIvarDeclaration(II); 3079 if (prevIvar) { 3080 Diag(Ivar->getLocation(), diag::err_duplicate_member) << II; 3081 Diag(prevIvar->getLocation(), diag::note_previous_definition); 3082 } 3083 } 3084 } 3085 } 3086 else if (ObjCImplementationDecl *IMPDecl = 3087 dyn_cast<ObjCImplementationDecl>(EnclosingDecl)) { 3088 assert(IMPDecl && "ActOnFields - missing ObjCImplementationDecl"); 3089 IMPDecl->ObjCAddInstanceVariablesToClassImpl(ClsFields, RecFields.size()); 3090 CheckImplementationIvars(IMPDecl, ClsFields, RecFields.size(), RBrac); 3091 } 3092 } 3093 3094 if (Attr) 3095 ProcessDeclAttributeList(Record, Attr); 3096} 3097 3098Sema::DeclTy *Sema::ActOnEnumConstant(Scope *S, DeclTy *theEnumDecl, 3099 DeclTy *lastEnumConst, 3100 SourceLocation IdLoc, IdentifierInfo *Id, 3101 SourceLocation EqualLoc, ExprTy *val) { 3102 EnumDecl *TheEnumDecl = cast<EnumDecl>(static_cast<Decl*>(theEnumDecl)); 3103 EnumConstantDecl *LastEnumConst = 3104 cast_or_null<EnumConstantDecl>(static_cast<Decl*>(lastEnumConst)); 3105 Expr *Val = static_cast<Expr*>(val); 3106 3107 // The scope passed in may not be a decl scope. Zip up the scope tree until 3108 // we find one that is. 3109 while ((S->getFlags() & Scope::DeclScope) == 0) 3110 S = S->getParent(); 3111 3112 // Verify that there isn't already something declared with this name in this 3113 // scope. 3114 Decl *PrevDecl = LookupDecl(Id, Decl::IDNS_Ordinary, S); 3115 if (PrevDecl && PrevDecl->isTemplateParameter()) { 3116 // Maybe we will complain about the shadowed template parameter. 3117 DiagnoseTemplateParameterShadow(IdLoc, PrevDecl); 3118 // Just pretend that we didn't see the previous declaration. 3119 PrevDecl = 0; 3120 } 3121 3122 if (PrevDecl) { 3123 // When in C++, we may get a TagDecl with the same name; in this case the 3124 // enum constant will 'hide' the tag. 3125 assert((getLangOptions().CPlusPlus || !isa<TagDecl>(PrevDecl)) && 3126 "Received TagDecl when not in C++!"); 3127 if (!isa<TagDecl>(PrevDecl) && isDeclInScope(PrevDecl, CurContext, S)) { 3128 if (isa<EnumConstantDecl>(PrevDecl)) 3129 Diag(IdLoc, diag::err_redefinition_of_enumerator) << Id; 3130 else 3131 Diag(IdLoc, diag::err_redefinition) << Id; 3132 Diag(PrevDecl->getLocation(), diag::note_previous_definition); 3133 delete Val; 3134 return 0; 3135 } 3136 } 3137 3138 llvm::APSInt EnumVal(32); 3139 QualType EltTy; 3140 if (Val) { 3141 // Make sure to promote the operand type to int. 3142 UsualUnaryConversions(Val); 3143 3144 // C99 6.7.2.2p2: Make sure we have an integer constant expression. 3145 SourceLocation ExpLoc; 3146 if (VerifyIntegerConstantExpression(Val, &EnumVal)) { 3147 delete Val; 3148 Val = 0; // Just forget about it. 3149 } else { 3150 EltTy = Val->getType(); 3151 } 3152 } 3153 3154 if (!Val) { 3155 if (LastEnumConst) { 3156 // Assign the last value + 1. 3157 EnumVal = LastEnumConst->getInitVal(); 3158 ++EnumVal; 3159 3160 // Check for overflow on increment. 3161 if (EnumVal < LastEnumConst->getInitVal()) 3162 Diag(IdLoc, diag::warn_enum_value_overflow); 3163 3164 EltTy = LastEnumConst->getType(); 3165 } else { 3166 // First value, set to zero. 3167 EltTy = Context.IntTy; 3168 EnumVal.zextOrTrunc(static_cast<uint32_t>(Context.getTypeSize(EltTy))); 3169 } 3170 } 3171 3172 EnumConstantDecl *New = 3173 EnumConstantDecl::Create(Context, TheEnumDecl, IdLoc, Id, EltTy, 3174 Val, EnumVal, 3175 LastEnumConst); 3176 3177 // Register this decl in the current scope stack. 3178 PushOnScopeChains(New, S); 3179 3180 // Add this enumerator into the enum itself. 3181 // FIXME: This means that the enumerator is stored in two 3182 // DeclContexts. This is not a long-term solution. 3183 New->setLexicalDeclContext(TheEnumDecl); 3184 TheEnumDecl->addDecl(Context, New, true); 3185 return New; 3186} 3187 3188// FIXME: For consistency with ActOnFields(), we should have the parser 3189// pass in the source location for the left/right braces. 3190void Sema::ActOnEnumBody(SourceLocation EnumLoc, DeclTy *EnumDeclX, 3191 DeclTy **Elements, unsigned NumElements) { 3192 EnumDecl *Enum = cast<EnumDecl>(static_cast<Decl*>(EnumDeclX)); 3193 3194 if (Enum) { 3195 if (EnumDecl *Def = cast_or_null<EnumDecl>(Enum->getDefinition(Context))) { 3196 // Diagnose code like: 3197 // enum e0 { 3198 // E0 = sizeof(enum e0 { E1 }) 3199 // }; 3200 Diag(Def->getLocation(), diag::err_nested_redefinition) 3201 << Enum->getDeclName(); 3202 Diag(Enum->getLocation(), diag::note_previous_definition); 3203 Enum->setInvalidDecl(); 3204 return; 3205 } 3206 } 3207 // TODO: If the result value doesn't fit in an int, it must be a long or long 3208 // long value. ISO C does not support this, but GCC does as an extension, 3209 // emit a warning. 3210 unsigned IntWidth = Context.Target.getIntWidth(); 3211 3212 // Verify that all the values are okay, compute the size of the values, and 3213 // reverse the list. 3214 unsigned NumNegativeBits = 0; 3215 unsigned NumPositiveBits = 0; 3216 3217 // Keep track of whether all elements have type int. 3218 bool AllElementsInt = true; 3219 3220 QualType EnumType = Context.getTypeDeclType(Enum); 3221 EnumConstantDecl *EltList = 0; 3222 for (unsigned i = 0; i != NumElements; ++i) { 3223 EnumConstantDecl *ECD = 3224 cast_or_null<EnumConstantDecl>(static_cast<Decl*>(Elements[i])); 3225 if (!ECD) continue; // Already issued a diagnostic. 3226 3227 // If the enum value doesn't fit in an int, emit an extension warning. 3228 const llvm::APSInt &InitVal = ECD->getInitVal(); 3229 assert(InitVal.getBitWidth() >= IntWidth && 3230 "Should have promoted value to int"); 3231 if (InitVal.getBitWidth() > IntWidth) { 3232 llvm::APSInt V(InitVal); 3233 V.trunc(IntWidth); 3234 V.extend(InitVal.getBitWidth()); 3235 if (V != InitVal) 3236 Diag(ECD->getLocation(), diag::ext_enum_value_not_int) 3237 << InitVal.toString(10); 3238 } 3239 3240 // Keep track of the size of positive and negative values. 3241 if (InitVal.isUnsigned() || InitVal.isNonNegative()) 3242 NumPositiveBits = std::max(NumPositiveBits, 3243 (unsigned)InitVal.getActiveBits()); 3244 else 3245 NumNegativeBits = std::max(NumNegativeBits, 3246 (unsigned)InitVal.getMinSignedBits()); 3247 3248 // Keep track of whether every enum element has type int (very commmon). 3249 if (AllElementsInt) 3250 AllElementsInt = ECD->getType() == Context.IntTy; 3251 3252 ECD->setNextDeclarator(EltList); 3253 EltList = ECD; 3254 } 3255 3256 // Figure out the type that should be used for this enum. 3257 // FIXME: Support attribute(packed) on enums and -fshort-enums. 3258 QualType BestType; 3259 unsigned BestWidth; 3260 3261 if (NumNegativeBits) { 3262 // If there is a negative value, figure out the smallest integer type (of 3263 // int/long/longlong) that fits. 3264 if (NumNegativeBits <= IntWidth && NumPositiveBits < IntWidth) { 3265 BestType = Context.IntTy; 3266 BestWidth = IntWidth; 3267 } else { 3268 BestWidth = Context.Target.getLongWidth(); 3269 3270 if (NumNegativeBits <= BestWidth && NumPositiveBits < BestWidth) 3271 BestType = Context.LongTy; 3272 else { 3273 BestWidth = Context.Target.getLongLongWidth(); 3274 3275 if (NumNegativeBits > BestWidth || NumPositiveBits >= BestWidth) 3276 Diag(Enum->getLocation(), diag::warn_enum_too_large); 3277 BestType = Context.LongLongTy; 3278 } 3279 } 3280 } else { 3281 // If there is no negative value, figure out which of uint, ulong, ulonglong 3282 // fits. 3283 if (NumPositiveBits <= IntWidth) { 3284 BestType = Context.UnsignedIntTy; 3285 BestWidth = IntWidth; 3286 } else if (NumPositiveBits <= 3287 (BestWidth = Context.Target.getLongWidth())) { 3288 BestType = Context.UnsignedLongTy; 3289 } else { 3290 BestWidth = Context.Target.getLongLongWidth(); 3291 assert(NumPositiveBits <= BestWidth && 3292 "How could an initializer get larger than ULL?"); 3293 BestType = Context.UnsignedLongLongTy; 3294 } 3295 } 3296 3297 // Loop over all of the enumerator constants, changing their types to match 3298 // the type of the enum if needed. 3299 for (unsigned i = 0; i != NumElements; ++i) { 3300 EnumConstantDecl *ECD = 3301 cast_or_null<EnumConstantDecl>(static_cast<Decl*>(Elements[i])); 3302 if (!ECD) continue; // Already issued a diagnostic. 3303 3304 // Standard C says the enumerators have int type, but we allow, as an 3305 // extension, the enumerators to be larger than int size. If each 3306 // enumerator value fits in an int, type it as an int, otherwise type it the 3307 // same as the enumerator decl itself. This means that in "enum { X = 1U }" 3308 // that X has type 'int', not 'unsigned'. 3309 if (ECD->getType() == Context.IntTy) { 3310 // Make sure the init value is signed. 3311 llvm::APSInt IV = ECD->getInitVal(); 3312 IV.setIsSigned(true); 3313 ECD->setInitVal(IV); 3314 3315 if (getLangOptions().CPlusPlus) 3316 // C++ [dcl.enum]p4: Following the closing brace of an 3317 // enum-specifier, each enumerator has the type of its 3318 // enumeration. 3319 ECD->setType(EnumType); 3320 continue; // Already int type. 3321 } 3322 3323 // Determine whether the value fits into an int. 3324 llvm::APSInt InitVal = ECD->getInitVal(); 3325 bool FitsInInt; 3326 if (InitVal.isUnsigned() || !InitVal.isNegative()) 3327 FitsInInt = InitVal.getActiveBits() < IntWidth; 3328 else 3329 FitsInInt = InitVal.getMinSignedBits() <= IntWidth; 3330 3331 // If it fits into an integer type, force it. Otherwise force it to match 3332 // the enum decl type. 3333 QualType NewTy; 3334 unsigned NewWidth; 3335 bool NewSign; 3336 if (FitsInInt) { 3337 NewTy = Context.IntTy; 3338 NewWidth = IntWidth; 3339 NewSign = true; 3340 } else if (ECD->getType() == BestType) { 3341 // Already the right type! 3342 if (getLangOptions().CPlusPlus) 3343 // C++ [dcl.enum]p4: Following the closing brace of an 3344 // enum-specifier, each enumerator has the type of its 3345 // enumeration. 3346 ECD->setType(EnumType); 3347 continue; 3348 } else { 3349 NewTy = BestType; 3350 NewWidth = BestWidth; 3351 NewSign = BestType->isSignedIntegerType(); 3352 } 3353 3354 // Adjust the APSInt value. 3355 InitVal.extOrTrunc(NewWidth); 3356 InitVal.setIsSigned(NewSign); 3357 ECD->setInitVal(InitVal); 3358 3359 // Adjust the Expr initializer and type. 3360 ECD->setInitExpr(new ImplicitCastExpr(NewTy, ECD->getInitExpr(), 3361 /*isLvalue=*/false)); 3362 if (getLangOptions().CPlusPlus) 3363 // C++ [dcl.enum]p4: Following the closing brace of an 3364 // enum-specifier, each enumerator has the type of its 3365 // enumeration. 3366 ECD->setType(EnumType); 3367 else 3368 ECD->setType(NewTy); 3369 } 3370 3371 Enum->completeDefinition(Context, BestType); 3372 Consumer.HandleTagDeclDefinition(Enum); 3373} 3374 3375Sema::DeclTy *Sema::ActOnFileScopeAsmDecl(SourceLocation Loc, 3376 ExprArg expr) { 3377 StringLiteral *AsmString = cast<StringLiteral>((Expr*)expr.release()); 3378 3379 return FileScopeAsmDecl::Create(Context, Loc, AsmString); 3380} 3381 3382 3383void Sema::ActOnPragmaPack(PragmaPackKind Kind, IdentifierInfo *Name, 3384 ExprTy *alignment, SourceLocation PragmaLoc, 3385 SourceLocation LParenLoc, SourceLocation RParenLoc) { 3386 Expr *Alignment = static_cast<Expr *>(alignment); 3387 3388 // If specified then alignment must be a "small" power of two. 3389 unsigned AlignmentVal = 0; 3390 if (Alignment) { 3391 llvm::APSInt Val; 3392 if (!Alignment->isIntegerConstantExpr(Val, Context) || 3393 !Val.isPowerOf2() || 3394 Val.getZExtValue() > 16) { 3395 Diag(PragmaLoc, diag::warn_pragma_pack_invalid_alignment); 3396 delete Alignment; 3397 return; // Ignore 3398 } 3399 3400 AlignmentVal = (unsigned) Val.getZExtValue(); 3401 } 3402 3403 switch (Kind) { 3404 case Action::PPK_Default: // pack([n]) 3405 PackContext.setAlignment(AlignmentVal); 3406 break; 3407 3408 case Action::PPK_Show: // pack(show) 3409 // Show the current alignment, making sure to show the right value 3410 // for the default. 3411 AlignmentVal = PackContext.getAlignment(); 3412 // FIXME: This should come from the target. 3413 if (AlignmentVal == 0) 3414 AlignmentVal = 8; 3415 Diag(PragmaLoc, diag::warn_pragma_pack_show) << AlignmentVal; 3416 break; 3417 3418 case Action::PPK_Push: // pack(push [, id] [, [n]) 3419 PackContext.push(Name); 3420 // Set the new alignment if specified. 3421 if (Alignment) 3422 PackContext.setAlignment(AlignmentVal); 3423 break; 3424 3425 case Action::PPK_Pop: // pack(pop [, id] [, n]) 3426 // MSDN, C/C++ Preprocessor Reference > Pragma Directives > pack: 3427 // "#pragma pack(pop, identifier, n) is undefined" 3428 if (Alignment && Name) 3429 Diag(PragmaLoc, diag::warn_pragma_pack_pop_identifer_and_alignment); 3430 3431 // Do the pop. 3432 if (!PackContext.pop(Name)) { 3433 // If a name was specified then failure indicates the name 3434 // wasn't found. Otherwise failure indicates the stack was 3435 // empty. 3436 Diag(PragmaLoc, diag::warn_pragma_pack_pop_failed) 3437 << (Name ? "no record matching name" : "stack empty"); 3438 3439 // FIXME: Warn about popping named records as MSVC does. 3440 } else { 3441 // Pop succeeded, set the new alignment if specified. 3442 if (Alignment) 3443 PackContext.setAlignment(AlignmentVal); 3444 } 3445 break; 3446 3447 default: 3448 assert(0 && "Invalid #pragma pack kind."); 3449 } 3450} 3451 3452bool PragmaPackStack::pop(IdentifierInfo *Name) { 3453 if (Stack.empty()) 3454 return false; 3455 3456 // If name is empty just pop top. 3457 if (!Name) { 3458 Alignment = Stack.back().first; 3459 Stack.pop_back(); 3460 return true; 3461 } 3462 3463 // Otherwise, find the named record. 3464 for (unsigned i = Stack.size(); i != 0; ) { 3465 --i; 3466 if (Stack[i].second == Name) { 3467 // Found it, pop up to and including this record. 3468 Alignment = Stack[i].first; 3469 Stack.erase(Stack.begin() + i, Stack.end()); 3470 return true; 3471 } 3472 } 3473 3474 return false; 3475} 3476