SemaDecl.cpp revision 66973121788ca645fe3d4a66179b9cfb6f2bce08
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/DiagnosticSema.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 LookupResult Result = LookupDecl(&II, Decl::IDNS_Ordinary, S, DC); 43 44 Decl *IIDecl = 0; 45 switch (Result.getKind()) { 46 case LookupResult::NotFound: 47 case LookupResult::FoundOverloaded: 48 case LookupResult::AmbiguousBaseSubobjectTypes: 49 case LookupResult::AmbiguousBaseSubobjects: 50 // FIXME: In the event of an ambiguous lookup, we could visit all of 51 // the entities found to determine whether they are all types. This 52 // might provide better diagnostics. 53 return 0; 54 55 case LookupResult::Found: 56 IIDecl = Result.getAsDecl(); 57 break; 58 } 59 60 if (isa<TypedefDecl>(IIDecl) || 61 isa<ObjCInterfaceDecl>(IIDecl) || 62 isa<TagDecl>(IIDecl) || 63 isa<TemplateTypeParmDecl>(IIDecl)) 64 return IIDecl; 65 return 0; 66} 67 68DeclContext *Sema::getContainingDC(DeclContext *DC) { 69 if (CXXMethodDecl *MD = dyn_cast<CXXMethodDecl>(DC)) { 70 // A C++ out-of-line method will return to the file declaration context. 71 if (MD->isOutOfLineDefinition()) 72 return MD->getLexicalDeclContext(); 73 74 // A C++ inline method is parsed *after* the topmost class it was declared in 75 // is fully parsed (it's "complete"). 76 // The parsing of a C++ inline method happens at the declaration context of 77 // the topmost (non-nested) class it is lexically declared in. 78 assert(isa<CXXRecordDecl>(MD->getParent()) && "C++ method not in Record."); 79 DC = MD->getParent(); 80 while (CXXRecordDecl *RD = dyn_cast<CXXRecordDecl>(DC->getLexicalParent())) 81 DC = RD; 82 83 // Return the declaration context of the topmost class the inline method is 84 // declared in. 85 return DC; 86 } 87 88 if (isa<ObjCMethodDecl>(DC)) 89 return Context.getTranslationUnitDecl(); 90 91 if (Decl *D = dyn_cast<Decl>(DC)) 92 return D->getLexicalDeclContext(); 93 94 return DC->getLexicalParent(); 95} 96 97void Sema::PushDeclContext(Scope *S, DeclContext *DC) { 98 assert(getContainingDC(DC) == CurContext && 99 "The next DeclContext should be lexically contained in the current one."); 100 CurContext = DC; 101 S->setEntity(DC); 102} 103 104void Sema::PopDeclContext() { 105 assert(CurContext && "DeclContext imbalance!"); 106 107 CurContext = getContainingDC(CurContext); 108} 109 110/// Add this decl to the scope shadowed decl chains. 111void Sema::PushOnScopeChains(NamedDecl *D, Scope *S) { 112 // Move up the scope chain until we find the nearest enclosing 113 // non-transparent context. The declaration will be introduced into this 114 // scope. 115 while (S->getEntity() && 116 ((DeclContext *)S->getEntity())->isTransparentContext()) 117 S = S->getParent(); 118 119 S->AddDecl(D); 120 121 // Add scoped declarations into their context, so that they can be 122 // found later. Declarations without a context won't be inserted 123 // into any context. 124 CurContext->addDecl(D); 125 126 // C++ [basic.scope]p4: 127 // -- exactly one declaration shall declare a class name or 128 // enumeration name that is not a typedef name and the other 129 // declarations shall all refer to the same object or 130 // enumerator, or all refer to functions and function templates; 131 // in this case the class name or enumeration name is hidden. 132 if (TagDecl *TD = dyn_cast<TagDecl>(D)) { 133 // We are pushing the name of a tag (enum or class). 134 if (CurContext->getLookupContext() 135 == TD->getDeclContext()->getLookupContext()) { 136 // We're pushing the tag into the current context, which might 137 // require some reshuffling in the identifier resolver. 138 IdentifierResolver::iterator 139 I = IdResolver.begin(TD->getDeclName(), CurContext, 140 false/*LookInParentCtx*/), 141 IEnd = IdResolver.end(); 142 if (I != IEnd && isDeclInScope(*I, CurContext, S)) { 143 NamedDecl *PrevDecl = *I; 144 for (; I != IEnd && isDeclInScope(*I, CurContext, S); 145 PrevDecl = *I, ++I) { 146 if (TD->declarationReplaces(*I)) { 147 // This is a redeclaration. Remove it from the chain and 148 // break out, so that we'll add in the shadowed 149 // declaration. 150 S->RemoveDecl(*I); 151 if (PrevDecl == *I) { 152 IdResolver.RemoveDecl(*I); 153 IdResolver.AddDecl(TD); 154 return; 155 } else { 156 IdResolver.RemoveDecl(*I); 157 break; 158 } 159 } 160 } 161 162 // There is already a declaration with the same name in the same 163 // scope, which is not a tag declaration. It must be found 164 // before we find the new declaration, so insert the new 165 // declaration at the end of the chain. 166 IdResolver.AddShadowedDecl(TD, PrevDecl); 167 168 return; 169 } 170 } 171 } else if (getLangOptions().CPlusPlus && isa<FunctionDecl>(D)) { 172 // We are pushing the name of a function, which might be an 173 // overloaded name. 174 FunctionDecl *FD = cast<FunctionDecl>(D); 175 DeclContext *DC = FD->getDeclContext()->getLookupContext(); 176 IdentifierResolver::iterator Redecl 177 = std::find_if(IdResolver.begin(FD->getDeclName(), DC, 178 false/*LookInParentCtx*/), 179 IdResolver.end(), 180 std::bind1st(std::mem_fun(&NamedDecl::declarationReplaces), 181 FD)); 182 if (Redecl != IdResolver.end()) { 183 // There is already a declaration of a function on our 184 // IdResolver chain. Replace it with this declaration. 185 S->RemoveDecl(*Redecl); 186 IdResolver.RemoveDecl(*Redecl); 187 } 188 } 189 190 IdResolver.AddDecl(D); 191} 192 193void Sema::ActOnPopScope(SourceLocation Loc, Scope *S) { 194 if (S->decl_empty()) return; 195 assert((S->getFlags() & (Scope::DeclScope | Scope::TemplateParamScope)) && 196 "Scope shouldn't contain decls!"); 197 198 for (Scope::decl_iterator I = S->decl_begin(), E = S->decl_end(); 199 I != E; ++I) { 200 Decl *TmpD = static_cast<Decl*>(*I); 201 assert(TmpD && "This decl didn't get pushed??"); 202 203 assert(isa<NamedDecl>(TmpD) && "Decl isn't NamedDecl?"); 204 NamedDecl *D = cast<NamedDecl>(TmpD); 205 206 if (!D->getDeclName()) continue; 207 208 // Remove this name from our lexical scope. 209 IdResolver.RemoveDecl(D); 210 } 211} 212 213/// getObjCInterfaceDecl - Look up a for a class declaration in the scope. 214/// return 0 if one not found. 215ObjCInterfaceDecl *Sema::getObjCInterfaceDecl(IdentifierInfo *Id) { 216 // The third "scope" argument is 0 since we aren't enabling lazy built-in 217 // creation from this context. 218 Decl *IDecl = LookupDecl(Id, Decl::IDNS_Ordinary, 0); 219 220 return dyn_cast_or_null<ObjCInterfaceDecl>(IDecl); 221} 222 223/// getNonFieldDeclScope - Retrieves the innermost scope, starting 224/// from S, where a non-field would be declared. This routine copes 225/// with the difference between C and C++ scoping rules in structs and 226/// unions. For example, the following code is well-formed in C but 227/// ill-formed in C++: 228/// @code 229/// struct S6 { 230/// enum { BAR } e; 231/// }; 232/// 233/// void test_S6() { 234/// struct S6 a; 235/// a.e = BAR; 236/// } 237/// @endcode 238/// For the declaration of BAR, this routine will return a different 239/// scope. The scope S will be the scope of the unnamed enumeration 240/// within S6. In C++, this routine will return the scope associated 241/// with S6, because the enumeration's scope is a transparent 242/// context but structures can contain non-field names. In C, this 243/// routine will return the translation unit scope, since the 244/// enumeration's scope is a transparent context and structures cannot 245/// contain non-field names. 246Scope *Sema::getNonFieldDeclScope(Scope *S) { 247 while (((S->getFlags() & Scope::DeclScope) == 0) || 248 (S->getEntity() && 249 ((DeclContext *)S->getEntity())->isTransparentContext()) || 250 (S->isClassScope() && !getLangOptions().CPlusPlus)) 251 S = S->getParent(); 252 return S; 253} 254 255/// LookupDecl - Look up the inner-most declaration in the specified 256/// namespace. NamespaceNameOnly - during lookup only namespace names 257/// are considered as required in C++ [basic.lookup.udir] 3.4.6.p1 258/// 'When looking up a namespace-name in a using-directive or 259/// namespace-alias-definition, only namespace names are considered.' 260/// 261/// Note: The use of this routine is deprecated. Please use 262/// LookupName, LookupQualifiedName, or LookupParsedName instead. 263Sema::LookupResult 264Sema::LookupDecl(DeclarationName Name, unsigned NSI, Scope *S, 265 const DeclContext *LookupCtx, 266 bool LookInParent) { 267 LookupCriteria::NameKind Kind; 268 if (NSI == Decl::IDNS_Ordinary) { 269 Kind = LookupCriteria::Ordinary; 270 } else if (NSI == Decl::IDNS_Tag) 271 Kind = LookupCriteria::Tag; 272 else { 273 assert(NSI == Decl::IDNS_Member &&"Unable to grok LookupDecl NSI argument"); 274 Kind = LookupCriteria::Member; 275 } 276 277 if (LookupCtx) 278 return LookupQualifiedName(const_cast<DeclContext *>(LookupCtx), Name, 279 LookupCriteria(Kind, !LookInParent, 280 getLangOptions().CPlusPlus)); 281 282 // Unqualified lookup 283 return LookupName(S, Name, 284 LookupCriteria(Kind, !LookInParent, 285 getLangOptions().CPlusPlus)); 286} 287 288void Sema::InitBuiltinVaListType() { 289 if (!Context.getBuiltinVaListType().isNull()) 290 return; 291 292 IdentifierInfo *VaIdent = &Context.Idents.get("__builtin_va_list"); 293 Decl *VaDecl = LookupDecl(VaIdent, Decl::IDNS_Ordinary, TUScope); 294 TypedefDecl *VaTypedef = cast<TypedefDecl>(VaDecl); 295 Context.setBuiltinVaListType(Context.getTypedefType(VaTypedef)); 296} 297 298/// LazilyCreateBuiltin - The specified Builtin-ID was first used at file scope. 299/// lazily create a decl for it. 300NamedDecl *Sema::LazilyCreateBuiltin(IdentifierInfo *II, unsigned bid, 301 Scope *S) { 302 Builtin::ID BID = (Builtin::ID)bid; 303 304 if (Context.BuiltinInfo.hasVAListUse(BID)) 305 InitBuiltinVaListType(); 306 307 QualType R = Context.BuiltinInfo.GetBuiltinType(BID, Context); 308 FunctionDecl *New = FunctionDecl::Create(Context, 309 Context.getTranslationUnitDecl(), 310 SourceLocation(), II, R, 311 FunctionDecl::Extern, false); 312 313 // Create Decl objects for each parameter, adding them to the 314 // FunctionDecl. 315 if (FunctionTypeProto *FT = dyn_cast<FunctionTypeProto>(R)) { 316 llvm::SmallVector<ParmVarDecl*, 16> Params; 317 for (unsigned i = 0, e = FT->getNumArgs(); i != e; ++i) 318 Params.push_back(ParmVarDecl::Create(Context, New, SourceLocation(), 0, 319 FT->getArgType(i), VarDecl::None, 0)); 320 New->setParams(Context, &Params[0], Params.size()); 321 } 322 323 324 325 // TUScope is the translation-unit scope to insert this function into. 326 // FIXME: This is hideous. We need to teach PushOnScopeChains to 327 // relate Scopes to DeclContexts, and probably eliminate CurContext 328 // entirely, but we're not there yet. 329 DeclContext *SavedContext = CurContext; 330 CurContext = Context.getTranslationUnitDecl(); 331 PushOnScopeChains(New, TUScope); 332 CurContext = SavedContext; 333 return New; 334} 335 336/// GetStdNamespace - This method gets the C++ "std" namespace. This is where 337/// everything from the standard library is defined. 338NamespaceDecl *Sema::GetStdNamespace() { 339 if (!StdNamespace) { 340 IdentifierInfo *StdIdent = &PP.getIdentifierTable().get("std"); 341 DeclContext *Global = Context.getTranslationUnitDecl(); 342 Decl *Std = LookupDecl(StdIdent, Decl::IDNS_Ordinary, 0, Global); 343 StdNamespace = dyn_cast_or_null<NamespaceDecl>(Std); 344 } 345 return StdNamespace; 346} 347 348/// MergeTypeDefDecl - We just parsed a typedef 'New' which has the same name 349/// and scope as a previous declaration 'Old'. Figure out how to resolve this 350/// situation, merging decls or emitting diagnostics as appropriate. 351/// 352TypedefDecl *Sema::MergeTypeDefDecl(TypedefDecl *New, Decl *OldD) { 353 bool objc_types = false; 354 // Allow multiple definitions for ObjC built-in typedefs. 355 // FIXME: Verify the underlying types are equivalent! 356 if (getLangOptions().ObjC1) { 357 const IdentifierInfo *TypeID = New->getIdentifier(); 358 switch (TypeID->getLength()) { 359 default: break; 360 case 2: 361 if (!TypeID->isStr("id")) 362 break; 363 Context.setObjCIdType(New); 364 objc_types = true; 365 break; 366 case 5: 367 if (!TypeID->isStr("Class")) 368 break; 369 Context.setObjCClassType(New); 370 objc_types = true; 371 return New; 372 case 3: 373 if (!TypeID->isStr("SEL")) 374 break; 375 Context.setObjCSelType(New); 376 objc_types = true; 377 return New; 378 case 8: 379 if (!TypeID->isStr("Protocol")) 380 break; 381 Context.setObjCProtoType(New->getUnderlyingType()); 382 objc_types = true; 383 return New; 384 } 385 // Fall through - the typedef name was not a builtin type. 386 } 387 // Verify the old decl was also a type. 388 TypeDecl *Old = dyn_cast<TypeDecl>(OldD); 389 if (!Old) { 390 Diag(New->getLocation(), diag::err_redefinition_different_kind) 391 << New->getDeclName(); 392 if (!objc_types) 393 Diag(OldD->getLocation(), diag::note_previous_definition); 394 return New; 395 } 396 397 // Determine the "old" type we'll use for checking and diagnostics. 398 QualType OldType; 399 if (TypedefDecl *OldTypedef = dyn_cast<TypedefDecl>(Old)) 400 OldType = OldTypedef->getUnderlyingType(); 401 else 402 OldType = Context.getTypeDeclType(Old); 403 404 // If the typedef types are not identical, reject them in all languages and 405 // with any extensions enabled. 406 407 if (OldType != New->getUnderlyingType() && 408 Context.getCanonicalType(OldType) != 409 Context.getCanonicalType(New->getUnderlyingType())) { 410 Diag(New->getLocation(), diag::err_redefinition_different_typedef) 411 << New->getUnderlyingType() << OldType; 412 if (!objc_types) 413 Diag(Old->getLocation(), diag::note_previous_definition); 414 return New; 415 } 416 if (objc_types) return New; 417 if (getLangOptions().Microsoft) return New; 418 419 // C++ [dcl.typedef]p2: 420 // In a given non-class scope, a typedef specifier can be used to 421 // redefine the name of any type declared in that scope to refer 422 // to the type to which it already refers. 423 if (getLangOptions().CPlusPlus && !isa<CXXRecordDecl>(CurContext)) 424 return New; 425 426 // In C, redeclaration of a type is a constraint violation (6.7.2.3p1). 427 // Apparently GCC, Intel, and Sun all silently ignore the redeclaration if 428 // *either* declaration is in a system header. The code below implements 429 // this adhoc compatibility rule. FIXME: The following code will not 430 // work properly when compiling ".i" files (containing preprocessed output). 431 if (PP.getDiagnostics().getSuppressSystemWarnings()) { 432 SourceManager &SrcMgr = Context.getSourceManager(); 433 if (SrcMgr.isInSystemHeader(Old->getLocation())) 434 return New; 435 if (SrcMgr.isInSystemHeader(New->getLocation())) 436 return New; 437 } 438 439 Diag(New->getLocation(), diag::err_redefinition) << New->getDeclName(); 440 Diag(Old->getLocation(), diag::note_previous_definition); 441 return New; 442} 443 444/// DeclhasAttr - returns true if decl Declaration already has the target 445/// attribute. 446static bool DeclHasAttr(const Decl *decl, const Attr *target) { 447 for (const Attr *attr = decl->getAttrs(); attr; attr = attr->getNext()) 448 if (attr->getKind() == target->getKind()) 449 return true; 450 451 return false; 452} 453 454/// MergeAttributes - append attributes from the Old decl to the New one. 455static void MergeAttributes(Decl *New, Decl *Old) { 456 Attr *attr = const_cast<Attr*>(Old->getAttrs()), *tmp; 457 458 while (attr) { 459 tmp = attr; 460 attr = attr->getNext(); 461 462 if (!DeclHasAttr(New, tmp)) { 463 tmp->setInherited(true); 464 New->addAttr(tmp); 465 } else { 466 tmp->setNext(0); 467 delete(tmp); 468 } 469 } 470 471 Old->invalidateAttrs(); 472} 473 474/// MergeFunctionDecl - We just parsed a function 'New' from 475/// declarator D which has the same name and scope as a previous 476/// declaration 'Old'. Figure out how to resolve this situation, 477/// merging decls or emitting diagnostics as appropriate. 478/// Redeclaration will be set true if this New is a redeclaration OldD. 479/// 480/// In C++, New and Old must be declarations that are not 481/// overloaded. Use IsOverload to determine whether New and Old are 482/// overloaded, and to select the Old declaration that New should be 483/// merged with. 484FunctionDecl * 485Sema::MergeFunctionDecl(FunctionDecl *New, Decl *OldD, bool &Redeclaration) { 486 assert(!isa<OverloadedFunctionDecl>(OldD) && 487 "Cannot merge with an overloaded function declaration"); 488 489 Redeclaration = false; 490 // Verify the old decl was also a function. 491 FunctionDecl *Old = dyn_cast<FunctionDecl>(OldD); 492 if (!Old) { 493 Diag(New->getLocation(), diag::err_redefinition_different_kind) 494 << New->getDeclName(); 495 Diag(OldD->getLocation(), diag::note_previous_definition); 496 return New; 497 } 498 499 // Determine whether the previous declaration was a definition, 500 // implicit declaration, or a declaration. 501 diag::kind PrevDiag; 502 if (Old->isThisDeclarationADefinition()) 503 PrevDiag = diag::note_previous_definition; 504 else if (Old->isImplicit()) 505 PrevDiag = diag::note_previous_implicit_declaration; 506 else 507 PrevDiag = diag::note_previous_declaration; 508 509 QualType OldQType = Context.getCanonicalType(Old->getType()); 510 QualType NewQType = Context.getCanonicalType(New->getType()); 511 512 if (getLangOptions().CPlusPlus) { 513 // (C++98 13.1p2): 514 // Certain function declarations cannot be overloaded: 515 // -- Function declarations that differ only in the return type 516 // cannot be overloaded. 517 QualType OldReturnType 518 = cast<FunctionType>(OldQType.getTypePtr())->getResultType(); 519 QualType NewReturnType 520 = cast<FunctionType>(NewQType.getTypePtr())->getResultType(); 521 if (OldReturnType != NewReturnType) { 522 Diag(New->getLocation(), diag::err_ovl_diff_return_type); 523 Diag(Old->getLocation(), PrevDiag); 524 Redeclaration = true; 525 return New; 526 } 527 528 const CXXMethodDecl* OldMethod = dyn_cast<CXXMethodDecl>(Old); 529 const CXXMethodDecl* NewMethod = dyn_cast<CXXMethodDecl>(New); 530 if (OldMethod && NewMethod) { 531 // -- Member function declarations with the same name and the 532 // same parameter types cannot be overloaded if any of them 533 // is a static member function declaration. 534 if (OldMethod->isStatic() || NewMethod->isStatic()) { 535 Diag(New->getLocation(), diag::err_ovl_static_nonstatic_member); 536 Diag(Old->getLocation(), PrevDiag); 537 return New; 538 } 539 540 // C++ [class.mem]p1: 541 // [...] A member shall not be declared twice in the 542 // member-specification, except that a nested class or member 543 // class template can be declared and then later defined. 544 if (OldMethod->getLexicalDeclContext() == 545 NewMethod->getLexicalDeclContext()) { 546 unsigned NewDiag; 547 if (isa<CXXConstructorDecl>(OldMethod)) 548 NewDiag = diag::err_constructor_redeclared; 549 else if (isa<CXXDestructorDecl>(NewMethod)) 550 NewDiag = diag::err_destructor_redeclared; 551 else if (isa<CXXConversionDecl>(NewMethod)) 552 NewDiag = diag::err_conv_function_redeclared; 553 else 554 NewDiag = diag::err_member_redeclared; 555 556 Diag(New->getLocation(), NewDiag); 557 Diag(Old->getLocation(), PrevDiag); 558 } 559 } 560 561 // (C++98 8.3.5p3): 562 // All declarations for a function shall agree exactly in both the 563 // return type and the parameter-type-list. 564 if (OldQType == NewQType) { 565 // We have a redeclaration. 566 MergeAttributes(New, Old); 567 Redeclaration = true; 568 return MergeCXXFunctionDecl(New, Old); 569 } 570 571 // Fall through for conflicting redeclarations and redefinitions. 572 } 573 574 // C: Function types need to be compatible, not identical. This handles 575 // duplicate function decls like "void f(int); void f(enum X);" properly. 576 if (!getLangOptions().CPlusPlus && 577 Context.typesAreCompatible(OldQType, NewQType)) { 578 MergeAttributes(New, Old); 579 Redeclaration = true; 580 return New; 581 } 582 583 // A function that has already been declared has been redeclared or defined 584 // with a different type- show appropriate diagnostic 585 586 // TODO: CHECK FOR CONFLICTS, multiple decls with same name in one scope. 587 // TODO: This is totally simplistic. It should handle merging functions 588 // together etc, merging extern int X; int X; ... 589 Diag(New->getLocation(), diag::err_conflicting_types) << New->getDeclName(); 590 Diag(Old->getLocation(), PrevDiag); 591 return New; 592} 593 594/// Predicate for C "tentative" external object definitions (C99 6.9.2). 595static bool isTentativeDefinition(VarDecl *VD) { 596 if (VD->isFileVarDecl()) 597 return (!VD->getInit() && 598 (VD->getStorageClass() == VarDecl::None || 599 VD->getStorageClass() == VarDecl::Static)); 600 return false; 601} 602 603/// CheckForFileScopedRedefinitions - Make sure we forgo redefinition errors 604/// when dealing with C "tentative" external object definitions (C99 6.9.2). 605void Sema::CheckForFileScopedRedefinitions(Scope *S, VarDecl *VD) { 606 bool VDIsTentative = isTentativeDefinition(VD); 607 bool VDIsIncompleteArray = VD->getType()->isIncompleteArrayType(); 608 609 // FIXME: I don't think this will actually see all of the 610 // redefinitions. Can't we check this property on-the-fly? 611 for (IdentifierResolver::iterator 612 I = IdResolver.begin(VD->getIdentifier(), 613 VD->getDeclContext(), false/*LookInParentCtx*/), 614 E = IdResolver.end(); I != E; ++I) { 615 if (*I != VD && isDeclInScope(*I, VD->getDeclContext(), S)) { 616 VarDecl *OldDecl = dyn_cast<VarDecl>(*I); 617 618 // Handle the following case: 619 // int a[10]; 620 // int a[]; - the code below makes sure we set the correct type. 621 // int a[11]; - this is an error, size isn't 10. 622 if (OldDecl && VDIsTentative && VDIsIncompleteArray && 623 OldDecl->getType()->isConstantArrayType()) 624 VD->setType(OldDecl->getType()); 625 626 // Check for "tentative" definitions. We can't accomplish this in 627 // MergeVarDecl since the initializer hasn't been attached. 628 if (!OldDecl || isTentativeDefinition(OldDecl) || VDIsTentative) 629 continue; 630 631 // Handle __private_extern__ just like extern. 632 if (OldDecl->getStorageClass() != VarDecl::Extern && 633 OldDecl->getStorageClass() != VarDecl::PrivateExtern && 634 VD->getStorageClass() != VarDecl::Extern && 635 VD->getStorageClass() != VarDecl::PrivateExtern) { 636 Diag(VD->getLocation(), diag::err_redefinition) << VD->getDeclName(); 637 Diag(OldDecl->getLocation(), diag::note_previous_definition); 638 } 639 } 640 } 641} 642 643/// MergeVarDecl - We just parsed a variable 'New' which has the same name 644/// and scope as a previous declaration 'Old'. Figure out how to resolve this 645/// situation, merging decls or emitting diagnostics as appropriate. 646/// 647/// Tentative definition rules (C99 6.9.2p2) are checked by 648/// FinalizeDeclaratorGroup. Unfortunately, we can't analyze tentative 649/// definitions here, since the initializer hasn't been attached. 650/// 651VarDecl *Sema::MergeVarDecl(VarDecl *New, Decl *OldD) { 652 // Verify the old decl was also a variable. 653 VarDecl *Old = dyn_cast<VarDecl>(OldD); 654 if (!Old) { 655 Diag(New->getLocation(), diag::err_redefinition_different_kind) 656 << New->getDeclName(); 657 Diag(OldD->getLocation(), diag::note_previous_definition); 658 return New; 659 } 660 661 MergeAttributes(New, Old); 662 663 // Merge the types 664 QualType MergedT = Context.mergeTypes(New->getType(), Old->getType()); 665 if (MergedT.isNull()) { 666 Diag(New->getLocation(), diag::err_redefinition_different_type) 667 << New->getDeclName(); 668 Diag(Old->getLocation(), diag::note_previous_definition); 669 return New; 670 } 671 New->setType(MergedT); 672 // C99 6.2.2p4: Check if we have a static decl followed by a non-static. 673 if (New->getStorageClass() == VarDecl::Static && 674 (Old->getStorageClass() == VarDecl::None || 675 Old->getStorageClass() == VarDecl::Extern)) { 676 Diag(New->getLocation(), diag::err_static_non_static) << New->getDeclName(); 677 Diag(Old->getLocation(), diag::note_previous_definition); 678 return New; 679 } 680 // C99 6.2.2p4: Check if we have a non-static decl followed by a static. 681 if (New->getStorageClass() != VarDecl::Static && 682 Old->getStorageClass() == VarDecl::Static) { 683 Diag(New->getLocation(), diag::err_non_static_static) << New->getDeclName(); 684 Diag(Old->getLocation(), diag::note_previous_definition); 685 return New; 686 } 687 // Variables with external linkage are analyzed in FinalizeDeclaratorGroup. 688 if (New->getStorageClass() != VarDecl::Extern && !New->isFileVarDecl()) { 689 Diag(New->getLocation(), diag::err_redefinition) << New->getDeclName(); 690 Diag(Old->getLocation(), diag::note_previous_definition); 691 } 692 return New; 693} 694 695/// CheckParmsForFunctionDef - Check that the parameters of the given 696/// function are appropriate for the definition of a function. This 697/// takes care of any checks that cannot be performed on the 698/// declaration itself, e.g., that the types of each of the function 699/// parameters are complete. 700bool Sema::CheckParmsForFunctionDef(FunctionDecl *FD) { 701 bool HasInvalidParm = false; 702 for (unsigned p = 0, NumParams = FD->getNumParams(); p < NumParams; ++p) { 703 ParmVarDecl *Param = FD->getParamDecl(p); 704 705 // C99 6.7.5.3p4: the parameters in a parameter type list in a 706 // function declarator that is part of a function definition of 707 // that function shall not have incomplete type. 708 if (!Param->isInvalidDecl() && 709 DiagnoseIncompleteType(Param->getLocation(), Param->getType(), 710 diag::err_typecheck_decl_incomplete_type)) { 711 Param->setInvalidDecl(); 712 HasInvalidParm = true; 713 } 714 715 // C99 6.9.1p5: If the declarator includes a parameter type list, the 716 // declaration of each parameter shall include an identifier. 717 if (Param->getIdentifier() == 0 && !getLangOptions().CPlusPlus) 718 Diag(Param->getLocation(), diag::err_parameter_name_omitted); 719 } 720 721 return HasInvalidParm; 722} 723 724/// ParsedFreeStandingDeclSpec - This method is invoked when a declspec with 725/// no declarator (e.g. "struct foo;") is parsed. 726Sema::DeclTy *Sema::ParsedFreeStandingDeclSpec(Scope *S, DeclSpec &DS) { 727 TagDecl *Tag 728 = dyn_cast_or_null<TagDecl>(static_cast<Decl *>(DS.getTypeRep())); 729 if (RecordDecl *Record = dyn_cast_or_null<RecordDecl>(Tag)) { 730 if (!Record->getDeclName() && Record->isDefinition() && 731 DS.getStorageClassSpec() != DeclSpec::SCS_typedef) 732 return BuildAnonymousStructOrUnion(S, DS, Record); 733 734 // Microsoft allows unnamed struct/union fields. Don't complain 735 // about them. 736 // FIXME: Should we support Microsoft's extensions in this area? 737 if (Record->getDeclName() && getLangOptions().Microsoft) 738 return Tag; 739 } 740 741 if (!DS.isMissingDeclaratorOk()) { 742 // Warn about typedefs of enums without names, since this is an 743 // extension in both Microsoft an GNU. 744 if (DS.getStorageClassSpec() == DeclSpec::SCS_typedef && 745 Tag && isa<EnumDecl>(Tag)) { 746 Diag(DS.getSourceRange().getBegin(), diag::ext_typedef_without_a_name) 747 << DS.getSourceRange(); 748 return Tag; 749 } 750 751 // FIXME: This diagnostic is emitted even when various previous 752 // errors occurred (see e.g. test/Sema/decl-invalid.c). However, 753 // DeclSpec has no means of communicating this information, and the 754 // responsible parser functions are quite far apart. 755 Diag(DS.getSourceRange().getBegin(), diag::err_no_declarators) 756 << DS.getSourceRange(); 757 return 0; 758 } 759 760 return Tag; 761} 762 763/// InjectAnonymousStructOrUnionMembers - Inject the members of the 764/// anonymous struct or union AnonRecord into the owning context Owner 765/// and scope S. This routine will be invoked just after we realize 766/// that an unnamed union or struct is actually an anonymous union or 767/// struct, e.g., 768/// 769/// @code 770/// union { 771/// int i; 772/// float f; 773/// }; // InjectAnonymousStructOrUnionMembers called here to inject i and 774/// // f into the surrounding scope.x 775/// @endcode 776/// 777/// This routine is recursive, injecting the names of nested anonymous 778/// structs/unions into the owning context and scope as well. 779bool Sema::InjectAnonymousStructOrUnionMembers(Scope *S, DeclContext *Owner, 780 RecordDecl *AnonRecord) { 781 bool Invalid = false; 782 for (RecordDecl::field_iterator F = AnonRecord->field_begin(), 783 FEnd = AnonRecord->field_end(); 784 F != FEnd; ++F) { 785 if ((*F)->getDeclName()) { 786 Decl *PrevDecl = LookupDecl((*F)->getDeclName(), Decl::IDNS_Ordinary, 787 S, Owner, false); 788 if (PrevDecl && !isa<TagDecl>(PrevDecl)) { 789 // C++ [class.union]p2: 790 // The names of the members of an anonymous union shall be 791 // distinct from the names of any other entity in the 792 // scope in which the anonymous union is declared. 793 unsigned diagKind 794 = AnonRecord->isUnion()? diag::err_anonymous_union_member_redecl 795 : diag::err_anonymous_struct_member_redecl; 796 Diag((*F)->getLocation(), diagKind) 797 << (*F)->getDeclName(); 798 Diag(PrevDecl->getLocation(), diag::note_previous_declaration); 799 Invalid = true; 800 } else { 801 // C++ [class.union]p2: 802 // For the purpose of name lookup, after the anonymous union 803 // definition, the members of the anonymous union are 804 // considered to have been defined in the scope in which the 805 // anonymous union is declared. 806 Owner->makeDeclVisibleInContext(*F); 807 S->AddDecl(*F); 808 IdResolver.AddDecl(*F); 809 } 810 } else if (const RecordType *InnerRecordType 811 = (*F)->getType()->getAsRecordType()) { 812 RecordDecl *InnerRecord = InnerRecordType->getDecl(); 813 if (InnerRecord->isAnonymousStructOrUnion()) 814 Invalid = Invalid || 815 InjectAnonymousStructOrUnionMembers(S, Owner, InnerRecord); 816 } 817 } 818 819 return Invalid; 820} 821 822/// ActOnAnonymousStructOrUnion - Handle the declaration of an 823/// anonymous structure or union. Anonymous unions are a C++ feature 824/// (C++ [class.union]) and a GNU C extension; anonymous structures 825/// are a GNU C and GNU C++ extension. 826Sema::DeclTy *Sema::BuildAnonymousStructOrUnion(Scope *S, DeclSpec &DS, 827 RecordDecl *Record) { 828 DeclContext *Owner = Record->getDeclContext(); 829 830 // Diagnose whether this anonymous struct/union is an extension. 831 if (Record->isUnion() && !getLangOptions().CPlusPlus) 832 Diag(Record->getLocation(), diag::ext_anonymous_union); 833 else if (!Record->isUnion()) 834 Diag(Record->getLocation(), diag::ext_anonymous_struct); 835 836 // C and C++ require different kinds of checks for anonymous 837 // structs/unions. 838 bool Invalid = false; 839 if (getLangOptions().CPlusPlus) { 840 const char* PrevSpec = 0; 841 // C++ [class.union]p3: 842 // Anonymous unions declared in a named namespace or in the 843 // global namespace shall be declared static. 844 if (DS.getStorageClassSpec() != DeclSpec::SCS_static && 845 (isa<TranslationUnitDecl>(Owner) || 846 (isa<NamespaceDecl>(Owner) && 847 cast<NamespaceDecl>(Owner)->getDeclName()))) { 848 Diag(Record->getLocation(), diag::err_anonymous_union_not_static); 849 Invalid = true; 850 851 // Recover by adding 'static'. 852 DS.SetStorageClassSpec(DeclSpec::SCS_static, SourceLocation(), PrevSpec); 853 } 854 // C++ [class.union]p3: 855 // A storage class is not allowed in a declaration of an 856 // anonymous union in a class scope. 857 else if (DS.getStorageClassSpec() != DeclSpec::SCS_unspecified && 858 isa<RecordDecl>(Owner)) { 859 Diag(DS.getStorageClassSpecLoc(), 860 diag::err_anonymous_union_with_storage_spec); 861 Invalid = true; 862 863 // Recover by removing the storage specifier. 864 DS.SetStorageClassSpec(DeclSpec::SCS_unspecified, SourceLocation(), 865 PrevSpec); 866 } 867 868 // C++ [class.union]p2: 869 // The member-specification of an anonymous union shall only 870 // define non-static data members. [Note: nested types and 871 // functions cannot be declared within an anonymous union. ] 872 for (DeclContext::decl_iterator Mem = Record->decls_begin(), 873 MemEnd = Record->decls_end(); 874 Mem != MemEnd; ++Mem) { 875 if (FieldDecl *FD = dyn_cast<FieldDecl>(*Mem)) { 876 // C++ [class.union]p3: 877 // An anonymous union shall not have private or protected 878 // members (clause 11). 879 if (FD->getAccess() == AS_protected || FD->getAccess() == AS_private) { 880 Diag(FD->getLocation(), diag::err_anonymous_record_nonpublic_member) 881 << (int)Record->isUnion() << (int)(FD->getAccess() == AS_protected); 882 Invalid = true; 883 } 884 } else if ((*Mem)->isImplicit()) { 885 // Any implicit members are fine. 886 } else if (RecordDecl *MemRecord = dyn_cast<RecordDecl>(*Mem)) { 887 if (!MemRecord->isAnonymousStructOrUnion() && 888 MemRecord->getDeclName()) { 889 // This is a nested type declaration. 890 Diag(MemRecord->getLocation(), diag::err_anonymous_record_with_type) 891 << (int)Record->isUnion(); 892 Invalid = true; 893 } 894 } else { 895 // We have something that isn't a non-static data 896 // member. Complain about it. 897 unsigned DK = diag::err_anonymous_record_bad_member; 898 if (isa<TypeDecl>(*Mem)) 899 DK = diag::err_anonymous_record_with_type; 900 else if (isa<FunctionDecl>(*Mem)) 901 DK = diag::err_anonymous_record_with_function; 902 else if (isa<VarDecl>(*Mem)) 903 DK = diag::err_anonymous_record_with_static; 904 Diag((*Mem)->getLocation(), DK) 905 << (int)Record->isUnion(); 906 Invalid = true; 907 } 908 } 909 } else { 910 // FIXME: Check GNU C semantics 911 if (Record->isUnion() && !Owner->isRecord()) { 912 Diag(Record->getLocation(), diag::err_anonymous_union_not_member) 913 << (int)getLangOptions().CPlusPlus; 914 Invalid = true; 915 } 916 } 917 918 if (!Record->isUnion() && !Owner->isRecord()) { 919 Diag(Record->getLocation(), diag::err_anonymous_struct_not_member) 920 << (int)getLangOptions().CPlusPlus; 921 Invalid = true; 922 } 923 924 // Create a declaration for this anonymous struct/union. 925 NamedDecl *Anon = 0; 926 if (RecordDecl *OwningClass = dyn_cast<RecordDecl>(Owner)) { 927 Anon = FieldDecl::Create(Context, OwningClass, Record->getLocation(), 928 /*IdentifierInfo=*/0, 929 Context.getTypeDeclType(Record), 930 /*BitWidth=*/0, /*Mutable=*/false); 931 Anon->setAccess(AS_public); 932 if (getLangOptions().CPlusPlus) 933 FieldCollector->Add(cast<FieldDecl>(Anon)); 934 } else { 935 VarDecl::StorageClass SC; 936 switch (DS.getStorageClassSpec()) { 937 default: assert(0 && "Unknown storage class!"); 938 case DeclSpec::SCS_unspecified: SC = VarDecl::None; break; 939 case DeclSpec::SCS_extern: SC = VarDecl::Extern; break; 940 case DeclSpec::SCS_static: SC = VarDecl::Static; break; 941 case DeclSpec::SCS_auto: SC = VarDecl::Auto; break; 942 case DeclSpec::SCS_register: SC = VarDecl::Register; break; 943 case DeclSpec::SCS_private_extern: SC = VarDecl::PrivateExtern; break; 944 case DeclSpec::SCS_mutable: 945 // mutable can only appear on non-static class members, so it's always 946 // an error here 947 Diag(Record->getLocation(), diag::err_mutable_nonmember); 948 Invalid = true; 949 SC = VarDecl::None; 950 break; 951 } 952 953 Anon = VarDecl::Create(Context, Owner, Record->getLocation(), 954 /*IdentifierInfo=*/0, 955 Context.getTypeDeclType(Record), 956 SC, DS.getSourceRange().getBegin()); 957 } 958 Anon->setImplicit(); 959 960 // Add the anonymous struct/union object to the current 961 // context. We'll be referencing this object when we refer to one of 962 // its members. 963 Owner->addDecl(Anon); 964 965 // Inject the members of the anonymous struct/union into the owning 966 // context and into the identifier resolver chain for name lookup 967 // purposes. 968 if (InjectAnonymousStructOrUnionMembers(S, Owner, Record)) 969 Invalid = true; 970 971 // Mark this as an anonymous struct/union type. Note that we do not 972 // do this until after we have already checked and injected the 973 // members of this anonymous struct/union type, because otherwise 974 // the members could be injected twice: once by DeclContext when it 975 // builds its lookup table, and once by 976 // InjectAnonymousStructOrUnionMembers. 977 Record->setAnonymousStructOrUnion(true); 978 979 if (Invalid) 980 Anon->setInvalidDecl(); 981 982 return Anon; 983} 984 985bool Sema::CheckSingleInitializer(Expr *&Init, QualType DeclType, 986 bool DirectInit) { 987 // Get the type before calling CheckSingleAssignmentConstraints(), since 988 // it can promote the expression. 989 QualType InitType = Init->getType(); 990 991 if (getLangOptions().CPlusPlus) { 992 // FIXME: I dislike this error message. A lot. 993 if (PerformImplicitConversion(Init, DeclType, "initializing", DirectInit)) 994 return Diag(Init->getSourceRange().getBegin(), 995 diag::err_typecheck_convert_incompatible) 996 << DeclType << Init->getType() << "initializing" 997 << Init->getSourceRange(); 998 999 return false; 1000 } 1001 1002 AssignConvertType ConvTy = CheckSingleAssignmentConstraints(DeclType, Init); 1003 return DiagnoseAssignmentResult(ConvTy, Init->getLocStart(), DeclType, 1004 InitType, Init, "initializing"); 1005} 1006 1007bool Sema::CheckStringLiteralInit(StringLiteral *strLiteral, QualType &DeclT) { 1008 const ArrayType *AT = Context.getAsArrayType(DeclT); 1009 1010 if (const IncompleteArrayType *IAT = dyn_cast<IncompleteArrayType>(AT)) { 1011 // C99 6.7.8p14. We have an array of character type with unknown size 1012 // being initialized to a string literal. 1013 llvm::APSInt ConstVal(32); 1014 ConstVal = strLiteral->getByteLength() + 1; 1015 // Return a new array type (C99 6.7.8p22). 1016 DeclT = Context.getConstantArrayType(IAT->getElementType(), ConstVal, 1017 ArrayType::Normal, 0); 1018 } else { 1019 const ConstantArrayType *CAT = cast<ConstantArrayType>(AT); 1020 // C99 6.7.8p14. We have an array of character type with known size. 1021 // FIXME: Avoid truncation for 64-bit length strings. 1022 if (strLiteral->getByteLength() > (unsigned)CAT->getSize().getZExtValue()) 1023 Diag(strLiteral->getSourceRange().getBegin(), 1024 diag::warn_initializer_string_for_char_array_too_long) 1025 << strLiteral->getSourceRange(); 1026 } 1027 // Set type from "char *" to "constant array of char". 1028 strLiteral->setType(DeclT); 1029 // For now, we always return false (meaning success). 1030 return false; 1031} 1032 1033StringLiteral *Sema::IsStringLiteralInit(Expr *Init, QualType DeclType) { 1034 const ArrayType *AT = Context.getAsArrayType(DeclType); 1035 if (AT && AT->getElementType()->isCharType()) { 1036 return dyn_cast<StringLiteral>(Init->IgnoreParens()); 1037 } 1038 return 0; 1039} 1040 1041bool Sema::CheckInitializerTypes(Expr *&Init, QualType &DeclType, 1042 SourceLocation InitLoc, 1043 DeclarationName InitEntity, 1044 bool DirectInit) { 1045 if (DeclType->isDependentType() || Init->isTypeDependent()) 1046 return false; 1047 1048 // C++ [dcl.init.ref]p1: 1049 // A variable declared to be a T&, that is "reference to type T" 1050 // (8.3.2), shall be initialized by an object, or function, of 1051 // type T or by an object that can be converted into a T. 1052 if (DeclType->isReferenceType()) 1053 return CheckReferenceInit(Init, DeclType, 0, false, DirectInit); 1054 1055 // C99 6.7.8p3: The type of the entity to be initialized shall be an array 1056 // of unknown size ("[]") or an object type that is not a variable array type. 1057 if (const VariableArrayType *VAT = Context.getAsVariableArrayType(DeclType)) 1058 return Diag(InitLoc, diag::err_variable_object_no_init) 1059 << VAT->getSizeExpr()->getSourceRange(); 1060 1061 InitListExpr *InitList = dyn_cast<InitListExpr>(Init); 1062 if (!InitList) { 1063 // FIXME: Handle wide strings 1064 if (StringLiteral *strLiteral = IsStringLiteralInit(Init, DeclType)) 1065 return CheckStringLiteralInit(strLiteral, DeclType); 1066 1067 // C++ [dcl.init]p14: 1068 // -- If the destination type is a (possibly cv-qualified) class 1069 // type: 1070 if (getLangOptions().CPlusPlus && DeclType->isRecordType()) { 1071 QualType DeclTypeC = Context.getCanonicalType(DeclType); 1072 QualType InitTypeC = Context.getCanonicalType(Init->getType()); 1073 1074 // -- If the initialization is direct-initialization, or if it is 1075 // copy-initialization where the cv-unqualified version of the 1076 // source type is the same class as, or a derived class of, the 1077 // class of the destination, constructors are considered. 1078 if ((DeclTypeC.getUnqualifiedType() == InitTypeC.getUnqualifiedType()) || 1079 IsDerivedFrom(InitTypeC, DeclTypeC)) { 1080 CXXConstructorDecl *Constructor 1081 = PerformInitializationByConstructor(DeclType, &Init, 1, 1082 InitLoc, Init->getSourceRange(), 1083 InitEntity, 1084 DirectInit? IK_Direct : IK_Copy); 1085 return Constructor == 0; 1086 } 1087 1088 // -- Otherwise (i.e., for the remaining copy-initialization 1089 // cases), user-defined conversion sequences that can 1090 // convert from the source type to the destination type or 1091 // (when a conversion function is used) to a derived class 1092 // thereof are enumerated as described in 13.3.1.4, and the 1093 // best one is chosen through overload resolution 1094 // (13.3). If the conversion cannot be done or is 1095 // ambiguous, the initialization is ill-formed. The 1096 // function selected is called with the initializer 1097 // expression as its argument; if the function is a 1098 // constructor, the call initializes a temporary of the 1099 // destination type. 1100 // FIXME: We're pretending to do copy elision here; return to 1101 // this when we have ASTs for such things. 1102 if (!PerformImplicitConversion(Init, DeclType, "initializing")) 1103 return false; 1104 1105 if (InitEntity) 1106 return Diag(InitLoc, diag::err_cannot_initialize_decl) 1107 << InitEntity << (int)(Init->isLvalue(Context) == Expr::LV_Valid) 1108 << Init->getType() << Init->getSourceRange(); 1109 else 1110 return Diag(InitLoc, diag::err_cannot_initialize_decl_noname) 1111 << DeclType << (int)(Init->isLvalue(Context) == Expr::LV_Valid) 1112 << Init->getType() << Init->getSourceRange(); 1113 } 1114 1115 // C99 6.7.8p16. 1116 if (DeclType->isArrayType()) 1117 return Diag(Init->getLocStart(), diag::err_array_init_list_required) 1118 << Init->getSourceRange(); 1119 1120 return CheckSingleInitializer(Init, DeclType, DirectInit); 1121 } else if (getLangOptions().CPlusPlus) { 1122 // C++ [dcl.init]p14: 1123 // [...] If the class is an aggregate (8.5.1), and the initializer 1124 // is a brace-enclosed list, see 8.5.1. 1125 // 1126 // Note: 8.5.1 is handled below; here, we diagnose the case where 1127 // we have an initializer list and a destination type that is not 1128 // an aggregate. 1129 // FIXME: In C++0x, this is yet another form of initialization. 1130 if (const RecordType *ClassRec = DeclType->getAsRecordType()) { 1131 const CXXRecordDecl *ClassDecl = cast<CXXRecordDecl>(ClassRec->getDecl()); 1132 if (!ClassDecl->isAggregate()) 1133 return Diag(InitLoc, diag::err_init_non_aggr_init_list) 1134 << DeclType << Init->getSourceRange(); 1135 } 1136 } 1137 1138 InitListChecker CheckInitList(this, InitList, DeclType); 1139 return CheckInitList.HadError(); 1140} 1141 1142/// GetNameForDeclarator - Determine the full declaration name for the 1143/// given Declarator. 1144DeclarationName Sema::GetNameForDeclarator(Declarator &D) { 1145 switch (D.getKind()) { 1146 case Declarator::DK_Abstract: 1147 assert(D.getIdentifier() == 0 && "abstract declarators have no name"); 1148 return DeclarationName(); 1149 1150 case Declarator::DK_Normal: 1151 assert (D.getIdentifier() != 0 && "normal declarators have an identifier"); 1152 return DeclarationName(D.getIdentifier()); 1153 1154 case Declarator::DK_Constructor: { 1155 QualType Ty = Context.getTypeDeclType((TypeDecl *)D.getDeclaratorIdType()); 1156 Ty = Context.getCanonicalType(Ty); 1157 return Context.DeclarationNames.getCXXConstructorName(Ty); 1158 } 1159 1160 case Declarator::DK_Destructor: { 1161 QualType Ty = Context.getTypeDeclType((TypeDecl *)D.getDeclaratorIdType()); 1162 Ty = Context.getCanonicalType(Ty); 1163 return Context.DeclarationNames.getCXXDestructorName(Ty); 1164 } 1165 1166 case Declarator::DK_Conversion: { 1167 QualType Ty = QualType::getFromOpaquePtr(D.getDeclaratorIdType()); 1168 Ty = Context.getCanonicalType(Ty); 1169 return Context.DeclarationNames.getCXXConversionFunctionName(Ty); 1170 } 1171 1172 case Declarator::DK_Operator: 1173 assert(D.getIdentifier() == 0 && "operator names have no identifier"); 1174 return Context.DeclarationNames.getCXXOperatorName( 1175 D.getOverloadedOperator()); 1176 } 1177 1178 assert(false && "Unknown name kind"); 1179 return DeclarationName(); 1180} 1181 1182/// isNearlyMatchingMemberFunction - Determine whether the C++ member 1183/// functions Declaration and Definition are "nearly" matching. This 1184/// heuristic is used to improve diagnostics in the case where an 1185/// out-of-line member function definition doesn't match any 1186/// declaration within the class. 1187static bool isNearlyMatchingMemberFunction(ASTContext &Context, 1188 FunctionDecl *Declaration, 1189 FunctionDecl *Definition) { 1190 if (Declaration->param_size() != Definition->param_size()) 1191 return false; 1192 for (unsigned Idx = 0; Idx < Declaration->param_size(); ++Idx) { 1193 QualType DeclParamTy = Declaration->getParamDecl(Idx)->getType(); 1194 QualType DefParamTy = Definition->getParamDecl(Idx)->getType(); 1195 1196 DeclParamTy = Context.getCanonicalType(DeclParamTy.getNonReferenceType()); 1197 DefParamTy = Context.getCanonicalType(DefParamTy.getNonReferenceType()); 1198 if (DeclParamTy.getUnqualifiedType() != DefParamTy.getUnqualifiedType()) 1199 return false; 1200 } 1201 1202 return true; 1203} 1204 1205Sema::DeclTy * 1206Sema::ActOnDeclarator(Scope *S, Declarator &D, DeclTy *lastDecl, 1207 bool IsFunctionDefinition) { 1208 NamedDecl *LastDeclarator = dyn_cast_or_null<NamedDecl>((Decl *)lastDecl); 1209 DeclarationName Name = GetNameForDeclarator(D); 1210 1211 // All of these full declarators require an identifier. If it doesn't have 1212 // one, the ParsedFreeStandingDeclSpec action should be used. 1213 if (!Name) { 1214 if (!D.getInvalidType()) // Reject this if we think it is valid. 1215 Diag(D.getDeclSpec().getSourceRange().getBegin(), 1216 diag::err_declarator_need_ident) 1217 << D.getDeclSpec().getSourceRange() << D.getSourceRange(); 1218 return 0; 1219 } 1220 1221 // The scope passed in may not be a decl scope. Zip up the scope tree until 1222 // we find one that is. 1223 while ((S->getFlags() & Scope::DeclScope) == 0 || 1224 (S->getFlags() & Scope::TemplateParamScope) != 0) 1225 S = S->getParent(); 1226 1227 DeclContext *DC; 1228 Decl *PrevDecl; 1229 NamedDecl *New; 1230 bool InvalidDecl = false; 1231 1232 // See if this is a redefinition of a variable in the same scope. 1233 if (!D.getCXXScopeSpec().isSet()) { 1234 DC = CurContext; 1235 PrevDecl = LookupDecl(Name, Decl::IDNS_Ordinary, S); 1236 } else { // Something like "int foo::x;" 1237 DC = static_cast<DeclContext*>(D.getCXXScopeSpec().getScopeRep()); 1238 PrevDecl = LookupDecl(Name, Decl::IDNS_Ordinary, S, DC); 1239 1240 // C++ 7.3.1.2p2: 1241 // Members (including explicit specializations of templates) of a named 1242 // namespace can also be defined outside that namespace by explicit 1243 // qualification of the name being defined, provided that the entity being 1244 // defined was already declared in the namespace and the definition appears 1245 // after the point of declaration in a namespace that encloses the 1246 // declarations namespace. 1247 // 1248 // Note that we only check the context at this point. We don't yet 1249 // have enough information to make sure that PrevDecl is actually 1250 // the declaration we want to match. For example, given: 1251 // 1252 // class X { 1253 // void f(); 1254 // void f(float); 1255 // }; 1256 // 1257 // void X::f(int) { } // ill-formed 1258 // 1259 // In this case, PrevDecl will point to the overload set 1260 // containing the two f's declared in X, but neither of them 1261 // matches. 1262 if (!CurContext->Encloses(DC)) { 1263 // The qualifying scope doesn't enclose the original declaration. 1264 // Emit diagnostic based on current scope. 1265 SourceLocation L = D.getIdentifierLoc(); 1266 SourceRange R = D.getCXXScopeSpec().getRange(); 1267 if (isa<FunctionDecl>(CurContext)) { 1268 Diag(L, diag::err_invalid_declarator_in_function) << Name << R; 1269 } else { 1270 Diag(L, diag::err_invalid_declarator_scope) 1271 << Name << cast<NamedDecl>(DC)->getDeclName() << R; 1272 } 1273 InvalidDecl = true; 1274 } 1275 } 1276 1277 if (PrevDecl && PrevDecl->isTemplateParameter()) { 1278 // Maybe we will complain about the shadowed template parameter. 1279 InvalidDecl = InvalidDecl 1280 || DiagnoseTemplateParameterShadow(D.getIdentifierLoc(), PrevDecl); 1281 // Just pretend that we didn't see the previous declaration. 1282 PrevDecl = 0; 1283 } 1284 1285 // In C++, the previous declaration we find might be a tag type 1286 // (class or enum). In this case, the new declaration will hide the 1287 // tag type. Note that this does does not apply if we're declaring a 1288 // typedef (C++ [dcl.typedef]p4). 1289 if (PrevDecl && PrevDecl->getIdentifierNamespace() == Decl::IDNS_Tag && 1290 D.getDeclSpec().getStorageClassSpec() != DeclSpec::SCS_typedef) 1291 PrevDecl = 0; 1292 1293 QualType R = GetTypeForDeclarator(D, S); 1294 assert(!R.isNull() && "GetTypeForDeclarator() returned null type"); 1295 1296 if (D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_typedef) { 1297 New = ActOnTypedefDeclarator(S, D, DC, R, LastDeclarator, PrevDecl, 1298 InvalidDecl); 1299 } else if (R.getTypePtr()->isFunctionType()) { 1300 New = ActOnFunctionDeclarator(S, D, DC, R, LastDeclarator, PrevDecl, 1301 IsFunctionDefinition, InvalidDecl); 1302 } else { 1303 New = ActOnVariableDeclarator(S, D, DC, R, LastDeclarator, PrevDecl, 1304 InvalidDecl); 1305 } 1306 1307 if (New == 0) 1308 return 0; 1309 1310 // Set the lexical context. If the declarator has a C++ scope specifier, the 1311 // lexical context will be different from the semantic context. 1312 New->setLexicalDeclContext(CurContext); 1313 1314 // If this has an identifier, add it to the scope stack. 1315 if (Name) 1316 PushOnScopeChains(New, S); 1317 // If any semantic error occurred, mark the decl as invalid. 1318 if (D.getInvalidType() || InvalidDecl) 1319 New->setInvalidDecl(); 1320 1321 return New; 1322} 1323 1324NamedDecl* 1325Sema::ActOnTypedefDeclarator(Scope* S, Declarator& D, DeclContext* DC, 1326 QualType R, Decl* LastDeclarator, 1327 Decl* PrevDecl, bool& InvalidDecl) { 1328 // Typedef declarators cannot be qualified (C++ [dcl.meaning]p1). 1329 if (D.getCXXScopeSpec().isSet()) { 1330 Diag(D.getIdentifierLoc(), diag::err_qualified_typedef_declarator) 1331 << D.getCXXScopeSpec().getRange(); 1332 InvalidDecl = true; 1333 // Pretend we didn't see the scope specifier. 1334 DC = 0; 1335 } 1336 1337 // Check that there are no default arguments (C++ only). 1338 if (getLangOptions().CPlusPlus) 1339 CheckExtraCXXDefaultArguments(D); 1340 1341 TypedefDecl *NewTD = ParseTypedefDecl(S, D, R, LastDeclarator); 1342 if (!NewTD) return 0; 1343 1344 // Handle attributes prior to checking for duplicates in MergeVarDecl 1345 ProcessDeclAttributes(NewTD, D); 1346 // Merge the decl with the existing one if appropriate. If the decl is 1347 // in an outer scope, it isn't the same thing. 1348 if (PrevDecl && isDeclInScope(PrevDecl, DC, S)) { 1349 NewTD = MergeTypeDefDecl(NewTD, PrevDecl); 1350 if (NewTD == 0) return 0; 1351 } 1352 1353 if (S->getFnParent() == 0) { 1354 // C99 6.7.7p2: If a typedef name specifies a variably modified type 1355 // then it shall have block scope. 1356 if (NewTD->getUnderlyingType()->isVariablyModifiedType()) { 1357 if (NewTD->getUnderlyingType()->isVariableArrayType()) 1358 Diag(D.getIdentifierLoc(), diag::err_vla_decl_in_file_scope); 1359 else 1360 Diag(D.getIdentifierLoc(), diag::err_vm_decl_in_file_scope); 1361 1362 InvalidDecl = true; 1363 } 1364 } 1365 return NewTD; 1366} 1367 1368NamedDecl* 1369Sema::ActOnVariableDeclarator(Scope* S, Declarator& D, DeclContext* DC, 1370 QualType R, Decl* LastDeclarator, 1371 Decl* PrevDecl, bool& InvalidDecl) { 1372 DeclarationName Name = GetNameForDeclarator(D); 1373 1374 // Check that there are no default arguments (C++ only). 1375 if (getLangOptions().CPlusPlus) 1376 CheckExtraCXXDefaultArguments(D); 1377 1378 if (R.getTypePtr()->isObjCInterfaceType()) { 1379 Diag(D.getIdentifierLoc(), diag::err_statically_allocated_object) 1380 << D.getIdentifier(); 1381 InvalidDecl = true; 1382 } 1383 1384 VarDecl *NewVD; 1385 VarDecl::StorageClass SC; 1386 switch (D.getDeclSpec().getStorageClassSpec()) { 1387 default: assert(0 && "Unknown storage class!"); 1388 case DeclSpec::SCS_unspecified: SC = VarDecl::None; break; 1389 case DeclSpec::SCS_extern: SC = VarDecl::Extern; break; 1390 case DeclSpec::SCS_static: SC = VarDecl::Static; break; 1391 case DeclSpec::SCS_auto: SC = VarDecl::Auto; break; 1392 case DeclSpec::SCS_register: SC = VarDecl::Register; break; 1393 case DeclSpec::SCS_private_extern: SC = VarDecl::PrivateExtern; break; 1394 case DeclSpec::SCS_mutable: 1395 // mutable can only appear on non-static class members, so it's always 1396 // an error here 1397 Diag(D.getIdentifierLoc(), diag::err_mutable_nonmember); 1398 InvalidDecl = true; 1399 SC = VarDecl::None; 1400 break; 1401 } 1402 1403 IdentifierInfo *II = Name.getAsIdentifierInfo(); 1404 if (!II) { 1405 Diag(D.getIdentifierLoc(), diag::err_bad_variable_name) 1406 << Name.getAsString(); 1407 return 0; 1408 } 1409 1410 if (DC->isRecord()) { 1411 // This is a static data member for a C++ class. 1412 NewVD = CXXClassVarDecl::Create(Context, cast<CXXRecordDecl>(DC), 1413 D.getIdentifierLoc(), II, 1414 R); 1415 } else { 1416 bool ThreadSpecified = D.getDeclSpec().isThreadSpecified(); 1417 if (S->getFnParent() == 0) { 1418 // C99 6.9p2: The storage-class specifiers auto and register shall not 1419 // appear in the declaration specifiers in an external declaration. 1420 if (SC == VarDecl::Auto || SC == VarDecl::Register) { 1421 Diag(D.getIdentifierLoc(), diag::err_typecheck_sclass_fscope); 1422 InvalidDecl = true; 1423 } 1424 } 1425 NewVD = VarDecl::Create(Context, DC, D.getIdentifierLoc(), 1426 II, R, SC, 1427 // FIXME: Move to DeclGroup... 1428 D.getDeclSpec().getSourceRange().getBegin()); 1429 NewVD->setThreadSpecified(ThreadSpecified); 1430 } 1431 NewVD->setNextDeclarator(LastDeclarator); 1432 1433 // Handle attributes prior to checking for duplicates in MergeVarDecl 1434 ProcessDeclAttributes(NewVD, D); 1435 1436 // Handle GNU asm-label extension (encoded as an attribute). 1437 if (Expr *E = (Expr*) D.getAsmLabel()) { 1438 // The parser guarantees this is a string. 1439 StringLiteral *SE = cast<StringLiteral>(E); 1440 NewVD->addAttr(new AsmLabelAttr(std::string(SE->getStrData(), 1441 SE->getByteLength()))); 1442 } 1443 1444 // Emit an error if an address space was applied to decl with local storage. 1445 // This includes arrays of objects with address space qualifiers, but not 1446 // automatic variables that point to other address spaces. 1447 // ISO/IEC TR 18037 S5.1.2 1448 if (NewVD->hasLocalStorage() && (NewVD->getType().getAddressSpace() != 0)) { 1449 Diag(D.getIdentifierLoc(), diag::err_as_qualified_auto_decl); 1450 InvalidDecl = true; 1451 } 1452 // Merge the decl with the existing one if appropriate. If the decl is 1453 // in an outer scope, it isn't the same thing. 1454 if (PrevDecl && isDeclInScope(PrevDecl, DC, S)) { 1455 if (isa<FieldDecl>(PrevDecl) && D.getCXXScopeSpec().isSet()) { 1456 // The user tried to define a non-static data member 1457 // out-of-line (C++ [dcl.meaning]p1). 1458 Diag(NewVD->getLocation(), diag::err_nonstatic_member_out_of_line) 1459 << D.getCXXScopeSpec().getRange(); 1460 NewVD->Destroy(Context); 1461 return 0; 1462 } 1463 1464 NewVD = MergeVarDecl(NewVD, PrevDecl); 1465 if (NewVD == 0) return 0; 1466 1467 if (D.getCXXScopeSpec().isSet()) { 1468 // No previous declaration in the qualifying scope. 1469 Diag(D.getIdentifierLoc(), diag::err_typecheck_no_member) 1470 << Name << D.getCXXScopeSpec().getRange(); 1471 InvalidDecl = true; 1472 } 1473 } 1474 return NewVD; 1475} 1476 1477NamedDecl* 1478Sema::ActOnFunctionDeclarator(Scope* S, Declarator& D, DeclContext* DC, 1479 QualType R, Decl *LastDeclarator, 1480 Decl* PrevDecl, bool IsFunctionDefinition, 1481 bool& InvalidDecl) { 1482 assert(R.getTypePtr()->isFunctionType()); 1483 1484 DeclarationName Name = GetNameForDeclarator(D); 1485 FunctionDecl::StorageClass SC = FunctionDecl::None; 1486 switch (D.getDeclSpec().getStorageClassSpec()) { 1487 default: assert(0 && "Unknown storage class!"); 1488 case DeclSpec::SCS_auto: 1489 case DeclSpec::SCS_register: 1490 case DeclSpec::SCS_mutable: 1491 Diag(D.getIdentifierLoc(), diag::err_typecheck_sclass_func); 1492 InvalidDecl = true; 1493 break; 1494 case DeclSpec::SCS_unspecified: SC = FunctionDecl::None; break; 1495 case DeclSpec::SCS_extern: SC = FunctionDecl::Extern; break; 1496 case DeclSpec::SCS_static: SC = FunctionDecl::Static; break; 1497 case DeclSpec::SCS_private_extern: SC = FunctionDecl::PrivateExtern;break; 1498 } 1499 1500 bool isInline = D.getDeclSpec().isInlineSpecified(); 1501 // bool isVirtual = D.getDeclSpec().isVirtualSpecified(); 1502 bool isExplicit = D.getDeclSpec().isExplicitSpecified(); 1503 1504 FunctionDecl *NewFD; 1505 if (D.getKind() == Declarator::DK_Constructor) { 1506 // This is a C++ constructor declaration. 1507 assert(DC->isRecord() && 1508 "Constructors can only be declared in a member context"); 1509 1510 InvalidDecl = InvalidDecl || CheckConstructorDeclarator(D, R, SC); 1511 1512 // Create the new declaration 1513 NewFD = CXXConstructorDecl::Create(Context, 1514 cast<CXXRecordDecl>(DC), 1515 D.getIdentifierLoc(), Name, R, 1516 isExplicit, isInline, 1517 /*isImplicitlyDeclared=*/false); 1518 1519 if (InvalidDecl) 1520 NewFD->setInvalidDecl(); 1521 } else if (D.getKind() == Declarator::DK_Destructor) { 1522 // This is a C++ destructor declaration. 1523 if (DC->isRecord()) { 1524 InvalidDecl = InvalidDecl || CheckDestructorDeclarator(D, R, SC); 1525 1526 NewFD = CXXDestructorDecl::Create(Context, 1527 cast<CXXRecordDecl>(DC), 1528 D.getIdentifierLoc(), Name, R, 1529 isInline, 1530 /*isImplicitlyDeclared=*/false); 1531 1532 if (InvalidDecl) 1533 NewFD->setInvalidDecl(); 1534 } else { 1535 Diag(D.getIdentifierLoc(), diag::err_destructor_not_member); 1536 1537 // Create a FunctionDecl to satisfy the function definition parsing 1538 // code path. 1539 NewFD = FunctionDecl::Create(Context, DC, D.getIdentifierLoc(), 1540 Name, R, SC, isInline, 1541 // FIXME: Move to DeclGroup... 1542 D.getDeclSpec().getSourceRange().getBegin()); 1543 InvalidDecl = true; 1544 NewFD->setInvalidDecl(); 1545 } 1546 } else if (D.getKind() == Declarator::DK_Conversion) { 1547 if (!DC->isRecord()) { 1548 Diag(D.getIdentifierLoc(), 1549 diag::err_conv_function_not_member); 1550 return 0; 1551 } else { 1552 InvalidDecl = InvalidDecl || CheckConversionDeclarator(D, R, SC); 1553 1554 NewFD = CXXConversionDecl::Create(Context, cast<CXXRecordDecl>(DC), 1555 D.getIdentifierLoc(), Name, R, 1556 isInline, isExplicit); 1557 1558 if (InvalidDecl) 1559 NewFD->setInvalidDecl(); 1560 } 1561 } else if (DC->isRecord()) { 1562 // This is a C++ method declaration. 1563 NewFD = CXXMethodDecl::Create(Context, cast<CXXRecordDecl>(DC), 1564 D.getIdentifierLoc(), Name, R, 1565 (SC == FunctionDecl::Static), isInline); 1566 } else { 1567 NewFD = FunctionDecl::Create(Context, DC, 1568 D.getIdentifierLoc(), 1569 Name, R, SC, isInline, 1570 // FIXME: Move to DeclGroup... 1571 D.getDeclSpec().getSourceRange().getBegin()); 1572 } 1573 NewFD->setNextDeclarator(LastDeclarator); 1574 1575 // Set the lexical context. If the declarator has a C++ 1576 // scope specifier, the lexical context will be different 1577 // from the semantic context. 1578 NewFD->setLexicalDeclContext(CurContext); 1579 1580 // Handle GNU asm-label extension (encoded as an attribute). 1581 if (Expr *E = (Expr*) D.getAsmLabel()) { 1582 // The parser guarantees this is a string. 1583 StringLiteral *SE = cast<StringLiteral>(E); 1584 NewFD->addAttr(new AsmLabelAttr(std::string(SE->getStrData(), 1585 SE->getByteLength()))); 1586 } 1587 1588 // Copy the parameter declarations from the declarator D to 1589 // the function declaration NewFD, if they are available. 1590 if (D.getNumTypeObjects() > 0) { 1591 DeclaratorChunk::FunctionTypeInfo &FTI = D.getTypeObject(0).Fun; 1592 1593 // Create Decl objects for each parameter, adding them to the 1594 // FunctionDecl. 1595 llvm::SmallVector<ParmVarDecl*, 16> Params; 1596 1597 // Check for C99 6.7.5.3p10 - foo(void) is a non-varargs 1598 // function that takes no arguments, not a function that takes a 1599 // single void argument. 1600 // We let through "const void" here because Sema::GetTypeForDeclarator 1601 // already checks for that case. 1602 if (FTI.NumArgs == 1 && !FTI.isVariadic && FTI.ArgInfo[0].Ident == 0 && 1603 FTI.ArgInfo[0].Param && 1604 ((ParmVarDecl*)FTI.ArgInfo[0].Param)->getType()->isVoidType()) { 1605 // empty arg list, don't push any params. 1606 ParmVarDecl *Param = (ParmVarDecl*)FTI.ArgInfo[0].Param; 1607 1608 // In C++, the empty parameter-type-list must be spelled "void"; a 1609 // typedef of void is not permitted. 1610 if (getLangOptions().CPlusPlus && 1611 Param->getType().getUnqualifiedType() != Context.VoidTy) { 1612 Diag(Param->getLocation(), diag::ext_param_typedef_of_void); 1613 } 1614 } else if (FTI.NumArgs > 0 && FTI.ArgInfo[0].Param != 0) { 1615 for (unsigned i = 0, e = FTI.NumArgs; i != e; ++i) 1616 Params.push_back((ParmVarDecl *)FTI.ArgInfo[i].Param); 1617 } 1618 1619 NewFD->setParams(Context, &Params[0], Params.size()); 1620 } else if (R->getAsTypedefType()) { 1621 // When we're declaring a function with a typedef, as in the 1622 // following example, we'll need to synthesize (unnamed) 1623 // parameters for use in the declaration. 1624 // 1625 // @code 1626 // typedef void fn(int); 1627 // fn f; 1628 // @endcode 1629 const FunctionTypeProto *FT = R->getAsFunctionTypeProto(); 1630 if (!FT) { 1631 // This is a typedef of a function with no prototype, so we 1632 // don't need to do anything. 1633 } else if ((FT->getNumArgs() == 0) || 1634 (FT->getNumArgs() == 1 && !FT->isVariadic() && 1635 FT->getArgType(0)->isVoidType())) { 1636 // This is a zero-argument function. We don't need to do anything. 1637 } else { 1638 // Synthesize a parameter for each argument type. 1639 llvm::SmallVector<ParmVarDecl*, 16> Params; 1640 for (FunctionTypeProto::arg_type_iterator ArgType = FT->arg_type_begin(); 1641 ArgType != FT->arg_type_end(); ++ArgType) { 1642 Params.push_back(ParmVarDecl::Create(Context, DC, 1643 SourceLocation(), 0, 1644 *ArgType, VarDecl::None, 1645 0)); 1646 } 1647 1648 NewFD->setParams(Context, &Params[0], Params.size()); 1649 } 1650 } 1651 1652 if (CXXConstructorDecl *Constructor = dyn_cast<CXXConstructorDecl>(NewFD)) 1653 InvalidDecl = InvalidDecl || CheckConstructor(Constructor); 1654 else if (isa<CXXDestructorDecl>(NewFD)) { 1655 CXXRecordDecl *Record = cast<CXXRecordDecl>(NewFD->getParent()); 1656 Record->setUserDeclaredDestructor(true); 1657 // C++ [class]p4: A POD-struct is an aggregate class that has [...] no 1658 // user-defined destructor. 1659 Record->setPOD(false); 1660 } else if (CXXConversionDecl *Conversion = 1661 dyn_cast<CXXConversionDecl>(NewFD)) 1662 ActOnConversionDeclarator(Conversion); 1663 1664 // Extra checking for C++ overloaded operators (C++ [over.oper]). 1665 if (NewFD->isOverloadedOperator() && 1666 CheckOverloadedOperatorDeclaration(NewFD)) 1667 NewFD->setInvalidDecl(); 1668 1669 // Merge the decl with the existing one if appropriate. Since C functions 1670 // are in a flat namespace, make sure we consider decls in outer scopes. 1671 if (PrevDecl && 1672 (!getLangOptions().CPlusPlus||isDeclInScope(PrevDecl, DC, S))) { 1673 bool Redeclaration = false; 1674 1675 // If C++, determine whether NewFD is an overload of PrevDecl or 1676 // a declaration that requires merging. If it's an overload, 1677 // there's no more work to do here; we'll just add the new 1678 // function to the scope. 1679 OverloadedFunctionDecl::function_iterator MatchedDecl; 1680 if (!getLangOptions().CPlusPlus || 1681 !IsOverload(NewFD, PrevDecl, MatchedDecl)) { 1682 Decl *OldDecl = PrevDecl; 1683 1684 // If PrevDecl was an overloaded function, extract the 1685 // FunctionDecl that matched. 1686 if (isa<OverloadedFunctionDecl>(PrevDecl)) 1687 OldDecl = *MatchedDecl; 1688 1689 // NewFD and PrevDecl represent declarations that need to be 1690 // merged. 1691 NewFD = MergeFunctionDecl(NewFD, OldDecl, Redeclaration); 1692 1693 if (NewFD == 0) return 0; 1694 if (Redeclaration) { 1695 NewFD->setPreviousDeclaration(cast<FunctionDecl>(OldDecl)); 1696 1697 // An out-of-line member function declaration must also be a 1698 // definition (C++ [dcl.meaning]p1). 1699 if (!IsFunctionDefinition && D.getCXXScopeSpec().isSet() && 1700 !InvalidDecl) { 1701 Diag(NewFD->getLocation(), diag::err_out_of_line_declaration) 1702 << D.getCXXScopeSpec().getRange(); 1703 NewFD->setInvalidDecl(); 1704 } 1705 } 1706 } 1707 1708 if (!Redeclaration && D.getCXXScopeSpec().isSet()) { 1709 // The user tried to provide an out-of-line definition for a 1710 // member function, but there was no such member function 1711 // declared (C++ [class.mfct]p2). For example: 1712 // 1713 // class X { 1714 // void f() const; 1715 // }; 1716 // 1717 // void X::f() { } // ill-formed 1718 // 1719 // Complain about this problem, and attempt to suggest close 1720 // matches (e.g., those that differ only in cv-qualifiers and 1721 // whether the parameter types are references). 1722 Diag(D.getIdentifierLoc(), diag::err_member_def_does_not_match) 1723 << cast<CXXRecordDecl>(DC)->getDeclName() 1724 << D.getCXXScopeSpec().getRange(); 1725 InvalidDecl = true; 1726 1727 PrevDecl = LookupDecl(Name, Decl::IDNS_Ordinary, S, DC); 1728 if (!PrevDecl) { 1729 // Nothing to suggest. 1730 } else if (OverloadedFunctionDecl *Ovl 1731 = dyn_cast<OverloadedFunctionDecl>(PrevDecl)) { 1732 for (OverloadedFunctionDecl::function_iterator 1733 Func = Ovl->function_begin(), 1734 FuncEnd = Ovl->function_end(); 1735 Func != FuncEnd; ++Func) { 1736 if (isNearlyMatchingMemberFunction(Context, *Func, NewFD)) 1737 Diag((*Func)->getLocation(), diag::note_member_def_close_match); 1738 1739 } 1740 } else if (CXXMethodDecl *Method = dyn_cast<CXXMethodDecl>(PrevDecl)) { 1741 // Suggest this no matter how mismatched it is; it's the only 1742 // thing we have. 1743 unsigned diag; 1744 if (isNearlyMatchingMemberFunction(Context, Method, NewFD)) 1745 diag = diag::note_member_def_close_match; 1746 else if (Method->getBody()) 1747 diag = diag::note_previous_definition; 1748 else 1749 diag = diag::note_previous_declaration; 1750 Diag(Method->getLocation(), diag); 1751 } 1752 1753 PrevDecl = 0; 1754 } 1755 } 1756 // Handle attributes. We need to have merged decls when handling attributes 1757 // (for example to check for conflicts, etc). 1758 ProcessDeclAttributes(NewFD, D); 1759 1760 if (getLangOptions().CPlusPlus) { 1761 // In C++, check default arguments now that we have merged decls. 1762 CheckCXXDefaultArguments(NewFD); 1763 1764 // An out-of-line member function declaration must also be a 1765 // definition (C++ [dcl.meaning]p1). 1766 if (!IsFunctionDefinition && D.getCXXScopeSpec().isSet() && !InvalidDecl) { 1767 Diag(NewFD->getLocation(), diag::err_out_of_line_declaration) 1768 << D.getCXXScopeSpec().getRange(); 1769 InvalidDecl = true; 1770 } 1771 } 1772 return NewFD; 1773} 1774 1775void Sema::InitializerElementNotConstant(const Expr *Init) { 1776 Diag(Init->getExprLoc(), diag::err_init_element_not_constant) 1777 << Init->getSourceRange(); 1778} 1779 1780bool Sema::CheckAddressConstantExpressionLValue(const Expr* Init) { 1781 switch (Init->getStmtClass()) { 1782 default: 1783 InitializerElementNotConstant(Init); 1784 return true; 1785 case Expr::ParenExprClass: { 1786 const ParenExpr* PE = cast<ParenExpr>(Init); 1787 return CheckAddressConstantExpressionLValue(PE->getSubExpr()); 1788 } 1789 case Expr::CompoundLiteralExprClass: 1790 return cast<CompoundLiteralExpr>(Init)->isFileScope(); 1791 case Expr::DeclRefExprClass: 1792 case Expr::QualifiedDeclRefExprClass: { 1793 const Decl *D = cast<DeclRefExpr>(Init)->getDecl(); 1794 if (const VarDecl *VD = dyn_cast<VarDecl>(D)) { 1795 if (VD->hasGlobalStorage()) 1796 return false; 1797 InitializerElementNotConstant(Init); 1798 return true; 1799 } 1800 if (isa<FunctionDecl>(D)) 1801 return false; 1802 InitializerElementNotConstant(Init); 1803 return true; 1804 } 1805 case Expr::MemberExprClass: { 1806 const MemberExpr *M = cast<MemberExpr>(Init); 1807 if (M->isArrow()) 1808 return CheckAddressConstantExpression(M->getBase()); 1809 return CheckAddressConstantExpressionLValue(M->getBase()); 1810 } 1811 case Expr::ArraySubscriptExprClass: { 1812 // FIXME: Should we pedwarn for "x[0+0]" (where x is a pointer)? 1813 const ArraySubscriptExpr *ASE = cast<ArraySubscriptExpr>(Init); 1814 return CheckAddressConstantExpression(ASE->getBase()) || 1815 CheckArithmeticConstantExpression(ASE->getIdx()); 1816 } 1817 case Expr::StringLiteralClass: 1818 case Expr::PredefinedExprClass: 1819 return false; 1820 case Expr::UnaryOperatorClass: { 1821 const UnaryOperator *Exp = cast<UnaryOperator>(Init); 1822 1823 // C99 6.6p9 1824 if (Exp->getOpcode() == UnaryOperator::Deref) 1825 return CheckAddressConstantExpression(Exp->getSubExpr()); 1826 1827 InitializerElementNotConstant(Init); 1828 return true; 1829 } 1830 } 1831} 1832 1833bool Sema::CheckAddressConstantExpression(const Expr* Init) { 1834 switch (Init->getStmtClass()) { 1835 default: 1836 InitializerElementNotConstant(Init); 1837 return true; 1838 case Expr::ParenExprClass: 1839 return CheckAddressConstantExpression(cast<ParenExpr>(Init)->getSubExpr()); 1840 case Expr::StringLiteralClass: 1841 case Expr::ObjCStringLiteralClass: 1842 return false; 1843 case Expr::CallExprClass: 1844 case Expr::CXXOperatorCallExprClass: 1845 // __builtin___CFStringMakeConstantString is a valid constant l-value. 1846 if (cast<CallExpr>(Init)->isBuiltinCall() == 1847 Builtin::BI__builtin___CFStringMakeConstantString) 1848 return false; 1849 1850 InitializerElementNotConstant(Init); 1851 return true; 1852 1853 case Expr::UnaryOperatorClass: { 1854 const UnaryOperator *Exp = cast<UnaryOperator>(Init); 1855 1856 // C99 6.6p9 1857 if (Exp->getOpcode() == UnaryOperator::AddrOf) 1858 return CheckAddressConstantExpressionLValue(Exp->getSubExpr()); 1859 1860 if (Exp->getOpcode() == UnaryOperator::Extension) 1861 return CheckAddressConstantExpression(Exp->getSubExpr()); 1862 1863 InitializerElementNotConstant(Init); 1864 return true; 1865 } 1866 case Expr::BinaryOperatorClass: { 1867 // FIXME: Should we pedwarn for expressions like "a + 1 + 2"? 1868 const BinaryOperator *Exp = cast<BinaryOperator>(Init); 1869 1870 Expr *PExp = Exp->getLHS(); 1871 Expr *IExp = Exp->getRHS(); 1872 if (IExp->getType()->isPointerType()) 1873 std::swap(PExp, IExp); 1874 1875 // FIXME: Should we pedwarn if IExp isn't an integer constant expression? 1876 return CheckAddressConstantExpression(PExp) || 1877 CheckArithmeticConstantExpression(IExp); 1878 } 1879 case Expr::ImplicitCastExprClass: 1880 case Expr::CStyleCastExprClass: { 1881 const Expr* SubExpr = cast<CastExpr>(Init)->getSubExpr(); 1882 if (Init->getStmtClass() == Expr::ImplicitCastExprClass) { 1883 // Check for implicit promotion 1884 if (SubExpr->getType()->isFunctionType() || 1885 SubExpr->getType()->isArrayType()) 1886 return CheckAddressConstantExpressionLValue(SubExpr); 1887 } 1888 1889 // Check for pointer->pointer cast 1890 if (SubExpr->getType()->isPointerType()) 1891 return CheckAddressConstantExpression(SubExpr); 1892 1893 if (SubExpr->getType()->isIntegralType()) { 1894 // Check for the special-case of a pointer->int->pointer cast; 1895 // this isn't standard, but some code requires it. See 1896 // PR2720 for an example. 1897 if (const CastExpr* SubCast = dyn_cast<CastExpr>(SubExpr)) { 1898 if (SubCast->getSubExpr()->getType()->isPointerType()) { 1899 unsigned IntWidth = Context.getIntWidth(SubCast->getType()); 1900 unsigned PointerWidth = Context.getTypeSize(Context.VoidPtrTy); 1901 if (IntWidth >= PointerWidth) { 1902 return CheckAddressConstantExpression(SubCast->getSubExpr()); 1903 } 1904 } 1905 } 1906 } 1907 if (SubExpr->getType()->isArithmeticType()) { 1908 return CheckArithmeticConstantExpression(SubExpr); 1909 } 1910 1911 InitializerElementNotConstant(Init); 1912 return true; 1913 } 1914 case Expr::ConditionalOperatorClass: { 1915 // FIXME: Should we pedwarn here? 1916 const ConditionalOperator *Exp = cast<ConditionalOperator>(Init); 1917 if (!Exp->getCond()->getType()->isArithmeticType()) { 1918 InitializerElementNotConstant(Init); 1919 return true; 1920 } 1921 if (CheckArithmeticConstantExpression(Exp->getCond())) 1922 return true; 1923 if (Exp->getLHS() && 1924 CheckAddressConstantExpression(Exp->getLHS())) 1925 return true; 1926 return CheckAddressConstantExpression(Exp->getRHS()); 1927 } 1928 case Expr::AddrLabelExprClass: 1929 return false; 1930 } 1931} 1932 1933static const Expr* FindExpressionBaseAddress(const Expr* E); 1934 1935static const Expr* FindExpressionBaseAddressLValue(const Expr* E) { 1936 switch (E->getStmtClass()) { 1937 default: 1938 return E; 1939 case Expr::ParenExprClass: { 1940 const ParenExpr* PE = cast<ParenExpr>(E); 1941 return FindExpressionBaseAddressLValue(PE->getSubExpr()); 1942 } 1943 case Expr::MemberExprClass: { 1944 const MemberExpr *M = cast<MemberExpr>(E); 1945 if (M->isArrow()) 1946 return FindExpressionBaseAddress(M->getBase()); 1947 return FindExpressionBaseAddressLValue(M->getBase()); 1948 } 1949 case Expr::ArraySubscriptExprClass: { 1950 const ArraySubscriptExpr *ASE = cast<ArraySubscriptExpr>(E); 1951 return FindExpressionBaseAddress(ASE->getBase()); 1952 } 1953 case Expr::UnaryOperatorClass: { 1954 const UnaryOperator *Exp = cast<UnaryOperator>(E); 1955 1956 if (Exp->getOpcode() == UnaryOperator::Deref) 1957 return FindExpressionBaseAddress(Exp->getSubExpr()); 1958 1959 return E; 1960 } 1961 } 1962} 1963 1964static const Expr* FindExpressionBaseAddress(const Expr* E) { 1965 switch (E->getStmtClass()) { 1966 default: 1967 return E; 1968 case Expr::ParenExprClass: { 1969 const ParenExpr* PE = cast<ParenExpr>(E); 1970 return FindExpressionBaseAddress(PE->getSubExpr()); 1971 } 1972 case Expr::UnaryOperatorClass: { 1973 const UnaryOperator *Exp = cast<UnaryOperator>(E); 1974 1975 // C99 6.6p9 1976 if (Exp->getOpcode() == UnaryOperator::AddrOf) 1977 return FindExpressionBaseAddressLValue(Exp->getSubExpr()); 1978 1979 if (Exp->getOpcode() == UnaryOperator::Extension) 1980 return FindExpressionBaseAddress(Exp->getSubExpr()); 1981 1982 return E; 1983 } 1984 case Expr::BinaryOperatorClass: { 1985 const BinaryOperator *Exp = cast<BinaryOperator>(E); 1986 1987 Expr *PExp = Exp->getLHS(); 1988 Expr *IExp = Exp->getRHS(); 1989 if (IExp->getType()->isPointerType()) 1990 std::swap(PExp, IExp); 1991 1992 return FindExpressionBaseAddress(PExp); 1993 } 1994 case Expr::ImplicitCastExprClass: { 1995 const Expr* SubExpr = cast<ImplicitCastExpr>(E)->getSubExpr(); 1996 1997 // Check for implicit promotion 1998 if (SubExpr->getType()->isFunctionType() || 1999 SubExpr->getType()->isArrayType()) 2000 return FindExpressionBaseAddressLValue(SubExpr); 2001 2002 // Check for pointer->pointer cast 2003 if (SubExpr->getType()->isPointerType()) 2004 return FindExpressionBaseAddress(SubExpr); 2005 2006 // We assume that we have an arithmetic expression here; 2007 // if we don't, we'll figure it out later 2008 return 0; 2009 } 2010 case Expr::CStyleCastExprClass: { 2011 const Expr* SubExpr = cast<CastExpr>(E)->getSubExpr(); 2012 2013 // Check for pointer->pointer cast 2014 if (SubExpr->getType()->isPointerType()) 2015 return FindExpressionBaseAddress(SubExpr); 2016 2017 // We assume that we have an arithmetic expression here; 2018 // if we don't, we'll figure it out later 2019 return 0; 2020 } 2021 } 2022} 2023 2024bool Sema::CheckArithmeticConstantExpression(const Expr* Init) { 2025 switch (Init->getStmtClass()) { 2026 default: 2027 InitializerElementNotConstant(Init); 2028 return true; 2029 case Expr::ParenExprClass: { 2030 const ParenExpr* PE = cast<ParenExpr>(Init); 2031 return CheckArithmeticConstantExpression(PE->getSubExpr()); 2032 } 2033 case Expr::FloatingLiteralClass: 2034 case Expr::IntegerLiteralClass: 2035 case Expr::CharacterLiteralClass: 2036 case Expr::ImaginaryLiteralClass: 2037 case Expr::TypesCompatibleExprClass: 2038 case Expr::CXXBoolLiteralExprClass: 2039 return false; 2040 case Expr::CallExprClass: 2041 case Expr::CXXOperatorCallExprClass: { 2042 const CallExpr *CE = cast<CallExpr>(Init); 2043 2044 // Allow any constant foldable calls to builtins. 2045 if (CE->isBuiltinCall() && CE->isEvaluatable(Context)) 2046 return false; 2047 2048 InitializerElementNotConstant(Init); 2049 return true; 2050 } 2051 case Expr::DeclRefExprClass: 2052 case Expr::QualifiedDeclRefExprClass: { 2053 const Decl *D = cast<DeclRefExpr>(Init)->getDecl(); 2054 if (isa<EnumConstantDecl>(D)) 2055 return false; 2056 InitializerElementNotConstant(Init); 2057 return true; 2058 } 2059 case Expr::CompoundLiteralExprClass: 2060 // Allow "(vector type){2,4}"; normal C constraints don't allow this, 2061 // but vectors are allowed to be magic. 2062 if (Init->getType()->isVectorType()) 2063 return false; 2064 InitializerElementNotConstant(Init); 2065 return true; 2066 case Expr::UnaryOperatorClass: { 2067 const UnaryOperator *Exp = cast<UnaryOperator>(Init); 2068 2069 switch (Exp->getOpcode()) { 2070 // Address, indirect, pre/post inc/dec, etc are not valid constant exprs. 2071 // See C99 6.6p3. 2072 default: 2073 InitializerElementNotConstant(Init); 2074 return true; 2075 case UnaryOperator::OffsetOf: 2076 if (Exp->getSubExpr()->getType()->isConstantSizeType()) 2077 return false; 2078 InitializerElementNotConstant(Init); 2079 return true; 2080 case UnaryOperator::Extension: 2081 case UnaryOperator::LNot: 2082 case UnaryOperator::Plus: 2083 case UnaryOperator::Minus: 2084 case UnaryOperator::Not: 2085 return CheckArithmeticConstantExpression(Exp->getSubExpr()); 2086 } 2087 } 2088 case Expr::SizeOfAlignOfExprClass: { 2089 const SizeOfAlignOfExpr *Exp = cast<SizeOfAlignOfExpr>(Init); 2090 // Special check for void types, which are allowed as an extension 2091 if (Exp->getTypeOfArgument()->isVoidType()) 2092 return false; 2093 // alignof always evaluates to a constant. 2094 // FIXME: is sizeof(int[3.0]) a constant expression? 2095 if (Exp->isSizeOf() && !Exp->getTypeOfArgument()->isConstantSizeType()) { 2096 InitializerElementNotConstant(Init); 2097 return true; 2098 } 2099 return false; 2100 } 2101 case Expr::BinaryOperatorClass: { 2102 const BinaryOperator *Exp = cast<BinaryOperator>(Init); 2103 2104 if (Exp->getLHS()->getType()->isArithmeticType() && 2105 Exp->getRHS()->getType()->isArithmeticType()) { 2106 return CheckArithmeticConstantExpression(Exp->getLHS()) || 2107 CheckArithmeticConstantExpression(Exp->getRHS()); 2108 } 2109 2110 if (Exp->getLHS()->getType()->isPointerType() && 2111 Exp->getRHS()->getType()->isPointerType()) { 2112 const Expr* LHSBase = FindExpressionBaseAddress(Exp->getLHS()); 2113 const Expr* RHSBase = FindExpressionBaseAddress(Exp->getRHS()); 2114 2115 // Only allow a null (constant integer) base; we could 2116 // allow some additional cases if necessary, but this 2117 // is sufficient to cover offsetof-like constructs. 2118 if (!LHSBase && !RHSBase) { 2119 return CheckAddressConstantExpression(Exp->getLHS()) || 2120 CheckAddressConstantExpression(Exp->getRHS()); 2121 } 2122 } 2123 2124 InitializerElementNotConstant(Init); 2125 return true; 2126 } 2127 case Expr::ImplicitCastExprClass: 2128 case Expr::CStyleCastExprClass: { 2129 const Expr *SubExpr = cast<CastExpr>(Init)->getSubExpr(); 2130 if (SubExpr->getType()->isArithmeticType()) 2131 return CheckArithmeticConstantExpression(SubExpr); 2132 2133 if (SubExpr->getType()->isPointerType()) { 2134 const Expr* Base = FindExpressionBaseAddress(SubExpr); 2135 // If the pointer has a null base, this is an offsetof-like construct 2136 if (!Base) 2137 return CheckAddressConstantExpression(SubExpr); 2138 } 2139 2140 InitializerElementNotConstant(Init); 2141 return true; 2142 } 2143 case Expr::ConditionalOperatorClass: { 2144 const ConditionalOperator *Exp = cast<ConditionalOperator>(Init); 2145 2146 // If GNU extensions are disabled, we require all operands to be arithmetic 2147 // constant expressions. 2148 if (getLangOptions().NoExtensions) { 2149 return CheckArithmeticConstantExpression(Exp->getCond()) || 2150 (Exp->getLHS() && CheckArithmeticConstantExpression(Exp->getLHS())) || 2151 CheckArithmeticConstantExpression(Exp->getRHS()); 2152 } 2153 2154 // Otherwise, we have to emulate some of the behavior of fold here. 2155 // Basically GCC treats things like "4 ? 1 : somefunc()" as a constant 2156 // because it can constant fold things away. To retain compatibility with 2157 // GCC code, we see if we can fold the condition to a constant (which we 2158 // should always be able to do in theory). If so, we only require the 2159 // specified arm of the conditional to be a constant. This is a horrible 2160 // hack, but is require by real world code that uses __builtin_constant_p. 2161 Expr::EvalResult EvalResult; 2162 if (!Exp->getCond()->Evaluate(EvalResult, Context) || 2163 EvalResult.HasSideEffects) { 2164 // If Evaluate couldn't fold it, CheckArithmeticConstantExpression 2165 // won't be able to either. Use it to emit the diagnostic though. 2166 bool Res = CheckArithmeticConstantExpression(Exp->getCond()); 2167 assert(Res && "Evaluate couldn't evaluate this constant?"); 2168 return Res; 2169 } 2170 2171 // Verify that the side following the condition is also a constant. 2172 const Expr *TrueSide = Exp->getLHS(), *FalseSide = Exp->getRHS(); 2173 if (EvalResult.Val.getInt() == 0) 2174 std::swap(TrueSide, FalseSide); 2175 2176 if (TrueSide && CheckArithmeticConstantExpression(TrueSide)) 2177 return true; 2178 2179 // Okay, the evaluated side evaluates to a constant, so we accept this. 2180 // Check to see if the other side is obviously not a constant. If so, 2181 // emit a warning that this is a GNU extension. 2182 if (FalseSide && !FalseSide->isEvaluatable(Context)) 2183 Diag(Init->getExprLoc(), 2184 diag::ext_typecheck_expression_not_constant_but_accepted) 2185 << FalseSide->getSourceRange(); 2186 return false; 2187 } 2188 } 2189} 2190 2191bool Sema::CheckForConstantInitializer(Expr *Init, QualType DclT) { 2192 if (DesignatedInitExpr *DIE = dyn_cast<DesignatedInitExpr>(Init)) 2193 Init = DIE->getInit(); 2194 2195 Init = Init->IgnoreParens(); 2196 2197 if (Init->isEvaluatable(Context)) 2198 return false; 2199 2200 // Look through CXXDefaultArgExprs; they have no meaning in this context. 2201 if (CXXDefaultArgExpr* DAE = dyn_cast<CXXDefaultArgExpr>(Init)) 2202 return CheckForConstantInitializer(DAE->getExpr(), DclT); 2203 2204 if (CompoundLiteralExpr *e = dyn_cast<CompoundLiteralExpr>(Init)) 2205 return CheckForConstantInitializer(e->getInitializer(), DclT); 2206 2207 if (InitListExpr *Exp = dyn_cast<InitListExpr>(Init)) { 2208 unsigned numInits = Exp->getNumInits(); 2209 for (unsigned i = 0; i < numInits; i++) { 2210 // FIXME: Need to get the type of the declaration for C++, 2211 // because it could be a reference? 2212 if (CheckForConstantInitializer(Exp->getInit(i), 2213 Exp->getInit(i)->getType())) 2214 return true; 2215 } 2216 return false; 2217 } 2218 2219 // FIXME: We can probably remove some of this code below, now that 2220 // Expr::Evaluate is doing the heavy lifting for scalars. 2221 2222 if (Init->isNullPointerConstant(Context)) 2223 return false; 2224 if (Init->getType()->isArithmeticType()) { 2225 QualType InitTy = Context.getCanonicalType(Init->getType()) 2226 .getUnqualifiedType(); 2227 if (InitTy == Context.BoolTy) { 2228 // Special handling for pointers implicitly cast to bool; 2229 // (e.g. "_Bool rr = &rr;"). This is only legal at the top level. 2230 if (ImplicitCastExpr* ICE = dyn_cast<ImplicitCastExpr>(Init)) { 2231 Expr* SubE = ICE->getSubExpr(); 2232 if (SubE->getType()->isPointerType() || 2233 SubE->getType()->isArrayType() || 2234 SubE->getType()->isFunctionType()) { 2235 return CheckAddressConstantExpression(Init); 2236 } 2237 } 2238 } else if (InitTy->isIntegralType()) { 2239 Expr* SubE = 0; 2240 if (CastExpr* CE = dyn_cast<CastExpr>(Init)) 2241 SubE = CE->getSubExpr(); 2242 // Special check for pointer cast to int; we allow as an extension 2243 // an address constant cast to an integer if the integer 2244 // is of an appropriate width (this sort of code is apparently used 2245 // in some places). 2246 // FIXME: Add pedwarn? 2247 // FIXME: Don't allow bitfields here! Need the FieldDecl for that. 2248 if (SubE && (SubE->getType()->isPointerType() || 2249 SubE->getType()->isArrayType() || 2250 SubE->getType()->isFunctionType())) { 2251 unsigned IntWidth = Context.getTypeSize(Init->getType()); 2252 unsigned PointerWidth = Context.getTypeSize(Context.VoidPtrTy); 2253 if (IntWidth >= PointerWidth) 2254 return CheckAddressConstantExpression(Init); 2255 } 2256 } 2257 2258 return CheckArithmeticConstantExpression(Init); 2259 } 2260 2261 if (Init->getType()->isPointerType()) 2262 return CheckAddressConstantExpression(Init); 2263 2264 // An array type at the top level that isn't an init-list must 2265 // be a string literal 2266 if (Init->getType()->isArrayType()) 2267 return false; 2268 2269 if (Init->getType()->isFunctionType()) 2270 return false; 2271 2272 // Allow block exprs at top level. 2273 if (Init->getType()->isBlockPointerType()) 2274 return false; 2275 2276 // GCC cast to union extension 2277 // note: the validity of the cast expr is checked by CheckCastTypes() 2278 if (CastExpr *C = dyn_cast<CastExpr>(Init)) { 2279 QualType T = C->getType(); 2280 return T->isUnionType() && CheckForConstantInitializer(C->getSubExpr(), T); 2281 } 2282 2283 InitializerElementNotConstant(Init); 2284 return true; 2285} 2286 2287void Sema::AddInitializerToDecl(DeclTy *dcl, ExprArg init) { 2288 AddInitializerToDecl(dcl, move(init), /*DirectInit=*/false); 2289} 2290 2291/// AddInitializerToDecl - Adds the initializer Init to the 2292/// declaration dcl. If DirectInit is true, this is C++ direct 2293/// initialization rather than copy initialization. 2294void Sema::AddInitializerToDecl(DeclTy *dcl, ExprArg init, bool DirectInit) { 2295 Decl *RealDecl = static_cast<Decl *>(dcl); 2296 Expr *Init = static_cast<Expr *>(init.release()); 2297 assert(Init && "missing initializer"); 2298 2299 // If there is no declaration, there was an error parsing it. Just ignore 2300 // the initializer. 2301 if (RealDecl == 0) { 2302 delete Init; 2303 return; 2304 } 2305 2306 VarDecl *VDecl = dyn_cast<VarDecl>(RealDecl); 2307 if (!VDecl) { 2308 Diag(RealDecl->getLocation(), diag::err_illegal_initializer); 2309 RealDecl->setInvalidDecl(); 2310 return; 2311 } 2312 // Get the decls type and save a reference for later, since 2313 // CheckInitializerTypes may change it. 2314 QualType DclT = VDecl->getType(), SavT = DclT; 2315 if (VDecl->isBlockVarDecl()) { 2316 VarDecl::StorageClass SC = VDecl->getStorageClass(); 2317 if (SC == VarDecl::Extern) { // C99 6.7.8p5 2318 Diag(VDecl->getLocation(), diag::err_block_extern_cant_init); 2319 VDecl->setInvalidDecl(); 2320 } else if (!VDecl->isInvalidDecl()) { 2321 if (CheckInitializerTypes(Init, DclT, VDecl->getLocation(), 2322 VDecl->getDeclName(), DirectInit)) 2323 VDecl->setInvalidDecl(); 2324 2325 // C++ 3.6.2p2, allow dynamic initialization of static initializers. 2326 if (!getLangOptions().CPlusPlus) { 2327 if (SC == VarDecl::Static) // C99 6.7.8p4. 2328 CheckForConstantInitializer(Init, DclT); 2329 } 2330 } 2331 } else if (VDecl->isFileVarDecl()) { 2332 if (VDecl->getStorageClass() == VarDecl::Extern) 2333 Diag(VDecl->getLocation(), diag::warn_extern_init); 2334 if (!VDecl->isInvalidDecl()) 2335 if (CheckInitializerTypes(Init, DclT, VDecl->getLocation(), 2336 VDecl->getDeclName(), DirectInit)) 2337 VDecl->setInvalidDecl(); 2338 2339 // C++ 3.6.2p2, allow dynamic initialization of static initializers. 2340 if (!getLangOptions().CPlusPlus) { 2341 // C99 6.7.8p4. All file scoped initializers need to be constant. 2342 CheckForConstantInitializer(Init, DclT); 2343 } 2344 } 2345 // If the type changed, it means we had an incomplete type that was 2346 // completed by the initializer. For example: 2347 // int ary[] = { 1, 3, 5 }; 2348 // "ary" transitions from a VariableArrayType to a ConstantArrayType. 2349 if (!VDecl->isInvalidDecl() && (DclT != SavT)) { 2350 VDecl->setType(DclT); 2351 Init->setType(DclT); 2352 } 2353 2354 // Attach the initializer to the decl. 2355 VDecl->setInit(Init); 2356 return; 2357} 2358 2359void Sema::ActOnUninitializedDecl(DeclTy *dcl) { 2360 Decl *RealDecl = static_cast<Decl *>(dcl); 2361 2362 // If there is no declaration, there was an error parsing it. Just ignore it. 2363 if (RealDecl == 0) 2364 return; 2365 2366 if (VarDecl *Var = dyn_cast<VarDecl>(RealDecl)) { 2367 QualType Type = Var->getType(); 2368 // C++ [dcl.init.ref]p3: 2369 // The initializer can be omitted for a reference only in a 2370 // parameter declaration (8.3.5), in the declaration of a 2371 // function return type, in the declaration of a class member 2372 // within its class declaration (9.2), and where the extern 2373 // specifier is explicitly used. 2374 if (Type->isReferenceType() && 2375 Var->getStorageClass() != VarDecl::Extern && 2376 Var->getStorageClass() != VarDecl::PrivateExtern) { 2377 Diag(Var->getLocation(), diag::err_reference_var_requires_init) 2378 << Var->getDeclName() 2379 << SourceRange(Var->getLocation(), Var->getLocation()); 2380 Var->setInvalidDecl(); 2381 return; 2382 } 2383 2384 // C++ [dcl.init]p9: 2385 // 2386 // If no initializer is specified for an object, and the object 2387 // is of (possibly cv-qualified) non-POD class type (or array 2388 // thereof), the object shall be default-initialized; if the 2389 // object is of const-qualified type, the underlying class type 2390 // shall have a user-declared default constructor. 2391 if (getLangOptions().CPlusPlus) { 2392 QualType InitType = Type; 2393 if (const ArrayType *Array = Context.getAsArrayType(Type)) 2394 InitType = Array->getElementType(); 2395 if (Var->getStorageClass() != VarDecl::Extern && 2396 Var->getStorageClass() != VarDecl::PrivateExtern && 2397 InitType->isRecordType()) { 2398 const CXXConstructorDecl *Constructor 2399 = PerformInitializationByConstructor(InitType, 0, 0, 2400 Var->getLocation(), 2401 SourceRange(Var->getLocation(), 2402 Var->getLocation()), 2403 Var->getDeclName(), 2404 IK_Default); 2405 if (!Constructor) 2406 Var->setInvalidDecl(); 2407 } 2408 } 2409 2410#if 0 2411 // FIXME: Temporarily disabled because we are not properly parsing 2412 // linkage specifications on declarations, e.g., 2413 // 2414 // extern "C" const CGPoint CGPointerZero; 2415 // 2416 // C++ [dcl.init]p9: 2417 // 2418 // If no initializer is specified for an object, and the 2419 // object is of (possibly cv-qualified) non-POD class type (or 2420 // array thereof), the object shall be default-initialized; if 2421 // the object is of const-qualified type, the underlying class 2422 // type shall have a user-declared default 2423 // constructor. Otherwise, if no initializer is specified for 2424 // an object, the object and its subobjects, if any, have an 2425 // indeterminate initial value; if the object or any of its 2426 // subobjects are of const-qualified type, the program is 2427 // ill-formed. 2428 // 2429 // This isn't technically an error in C, so we don't diagnose it. 2430 // 2431 // FIXME: Actually perform the POD/user-defined default 2432 // constructor check. 2433 if (getLangOptions().CPlusPlus && 2434 Context.getCanonicalType(Type).isConstQualified() && 2435 Var->getStorageClass() != VarDecl::Extern) 2436 Diag(Var->getLocation(), diag::err_const_var_requires_init) 2437 << Var->getName() 2438 << SourceRange(Var->getLocation(), Var->getLocation()); 2439#endif 2440 } 2441} 2442 2443/// The declarators are chained together backwards, reverse the list. 2444Sema::DeclTy *Sema::FinalizeDeclaratorGroup(Scope *S, DeclTy *group) { 2445 // Often we have single declarators, handle them quickly. 2446 Decl *GroupDecl = static_cast<Decl*>(group); 2447 if (GroupDecl == 0) 2448 return 0; 2449 2450 Decl *Group = dyn_cast<Decl>(GroupDecl); 2451 Decl *NewGroup = 0; 2452 if (Group->getNextDeclarator() == 0) 2453 NewGroup = Group; 2454 else { // reverse the list. 2455 while (Group) { 2456 Decl *Next = Group->getNextDeclarator(); 2457 Group->setNextDeclarator(NewGroup); 2458 NewGroup = Group; 2459 Group = Next; 2460 } 2461 } 2462 // Perform semantic analysis that depends on having fully processed both 2463 // the declarator and initializer. 2464 for (Decl *ID = NewGroup; ID; ID = ID->getNextDeclarator()) { 2465 VarDecl *IDecl = dyn_cast<VarDecl>(ID); 2466 if (!IDecl) 2467 continue; 2468 QualType T = IDecl->getType(); 2469 2470 if (T->isVariableArrayType()) { 2471 const VariableArrayType *VAT = Context.getAsVariableArrayType(T); 2472 2473 // FIXME: This won't give the correct result for 2474 // int a[10][n]; 2475 SourceRange SizeRange = VAT->getSizeExpr()->getSourceRange(); 2476 if (IDecl->isFileVarDecl()) { 2477 Diag(IDecl->getLocation(), diag::err_vla_decl_in_file_scope) << 2478 SizeRange; 2479 2480 IDecl->setInvalidDecl(); 2481 } else { 2482 // C99 6.7.5.2p2: If an identifier is declared to be an object with 2483 // static storage duration, it shall not have a variable length array. 2484 if (IDecl->getStorageClass() == VarDecl::Static) { 2485 Diag(IDecl->getLocation(), diag::err_vla_decl_has_static_storage) 2486 << SizeRange; 2487 IDecl->setInvalidDecl(); 2488 } else if (IDecl->getStorageClass() == VarDecl::Extern) { 2489 Diag(IDecl->getLocation(), diag::err_vla_decl_has_extern_linkage) 2490 << SizeRange; 2491 IDecl->setInvalidDecl(); 2492 } 2493 } 2494 } else if (T->isVariablyModifiedType()) { 2495 if (IDecl->isFileVarDecl()) { 2496 Diag(IDecl->getLocation(), diag::err_vm_decl_in_file_scope); 2497 IDecl->setInvalidDecl(); 2498 } else { 2499 if (IDecl->getStorageClass() == VarDecl::Extern) { 2500 Diag(IDecl->getLocation(), diag::err_vm_decl_has_extern_linkage); 2501 IDecl->setInvalidDecl(); 2502 } 2503 } 2504 } 2505 2506 // Block scope. C99 6.7p7: If an identifier for an object is declared with 2507 // no linkage (C99 6.2.2p6), the type for the object shall be complete... 2508 if (IDecl->isBlockVarDecl() && 2509 IDecl->getStorageClass() != VarDecl::Extern) { 2510 if (!IDecl->isInvalidDecl() && 2511 DiagnoseIncompleteType(IDecl->getLocation(), T, 2512 diag::err_typecheck_decl_incomplete_type)) 2513 IDecl->setInvalidDecl(); 2514 } 2515 // File scope. C99 6.9.2p2: A declaration of an identifier for and 2516 // object that has file scope without an initializer, and without a 2517 // storage-class specifier or with the storage-class specifier "static", 2518 // constitutes a tentative definition. Note: A tentative definition with 2519 // external linkage is valid (C99 6.2.2p5). 2520 if (isTentativeDefinition(IDecl)) { 2521 if (T->isIncompleteArrayType()) { 2522 // C99 6.9.2 (p2, p5): Implicit initialization causes an incomplete 2523 // array to be completed. Don't issue a diagnostic. 2524 } else if (!IDecl->isInvalidDecl() && 2525 DiagnoseIncompleteType(IDecl->getLocation(), T, 2526 diag::err_typecheck_decl_incomplete_type)) 2527 // C99 6.9.2p3: If the declaration of an identifier for an object is 2528 // a tentative definition and has internal linkage (C99 6.2.2p3), the 2529 // declared type shall not be an incomplete type. 2530 IDecl->setInvalidDecl(); 2531 } 2532 if (IDecl->isFileVarDecl()) 2533 CheckForFileScopedRedefinitions(S, IDecl); 2534 } 2535 return NewGroup; 2536} 2537 2538/// ActOnParamDeclarator - Called from Parser::ParseFunctionDeclarator() 2539/// to introduce parameters into function prototype scope. 2540Sema::DeclTy * 2541Sema::ActOnParamDeclarator(Scope *S, Declarator &D) { 2542 const DeclSpec &DS = D.getDeclSpec(); 2543 2544 // Verify C99 6.7.5.3p2: The only SCS allowed is 'register'. 2545 VarDecl::StorageClass StorageClass = VarDecl::None; 2546 if (DS.getStorageClassSpec() == DeclSpec::SCS_register) { 2547 StorageClass = VarDecl::Register; 2548 } else if (DS.getStorageClassSpec() != DeclSpec::SCS_unspecified) { 2549 Diag(DS.getStorageClassSpecLoc(), 2550 diag::err_invalid_storage_class_in_func_decl); 2551 D.getMutableDeclSpec().ClearStorageClassSpecs(); 2552 } 2553 if (DS.isThreadSpecified()) { 2554 Diag(DS.getThreadSpecLoc(), 2555 diag::err_invalid_storage_class_in_func_decl); 2556 D.getMutableDeclSpec().ClearStorageClassSpecs(); 2557 } 2558 2559 // Check that there are no default arguments inside the type of this 2560 // parameter (C++ only). 2561 if (getLangOptions().CPlusPlus) 2562 CheckExtraCXXDefaultArguments(D); 2563 2564 // In this context, we *do not* check D.getInvalidType(). If the declarator 2565 // type was invalid, GetTypeForDeclarator() still returns a "valid" type, 2566 // though it will not reflect the user specified type. 2567 QualType parmDeclType = GetTypeForDeclarator(D, S); 2568 2569 assert(!parmDeclType.isNull() && "GetTypeForDeclarator() returned null type"); 2570 2571 // TODO: CHECK FOR CONFLICTS, multiple decls with same name in one scope. 2572 // Can this happen for params? We already checked that they don't conflict 2573 // among each other. Here they can only shadow globals, which is ok. 2574 IdentifierInfo *II = D.getIdentifier(); 2575 if (II) { 2576 if (Decl *PrevDecl = LookupDecl(II, Decl::IDNS_Ordinary, S)) { 2577 if (PrevDecl->isTemplateParameter()) { 2578 // Maybe we will complain about the shadowed template parameter. 2579 DiagnoseTemplateParameterShadow(D.getIdentifierLoc(), PrevDecl); 2580 // Just pretend that we didn't see the previous declaration. 2581 PrevDecl = 0; 2582 } else if (S->isDeclScope(PrevDecl)) { 2583 Diag(D.getIdentifierLoc(), diag::err_param_redefinition) << II; 2584 2585 // Recover by removing the name 2586 II = 0; 2587 D.SetIdentifier(0, D.getIdentifierLoc()); 2588 } 2589 } 2590 } 2591 2592 // Perform the default function/array conversion (C99 6.7.5.3p[7,8]). 2593 // Doing the promotion here has a win and a loss. The win is the type for 2594 // both Decl's and DeclRefExpr's will match (a convenient invariant for the 2595 // code generator). The loss is the orginal type isn't preserved. For example: 2596 // 2597 // void func(int parmvardecl[5]) { // convert "int [5]" to "int *" 2598 // int blockvardecl[5]; 2599 // sizeof(parmvardecl); // size == 4 2600 // sizeof(blockvardecl); // size == 20 2601 // } 2602 // 2603 // For expressions, all implicit conversions are captured using the 2604 // ImplicitCastExpr AST node (we have no such mechanism for Decl's). 2605 // 2606 // FIXME: If a source translation tool needs to see the original type, then 2607 // we need to consider storing both types (in ParmVarDecl)... 2608 // 2609 if (parmDeclType->isArrayType()) { 2610 // int x[restrict 4] -> int *restrict 2611 parmDeclType = Context.getArrayDecayedType(parmDeclType); 2612 } else if (parmDeclType->isFunctionType()) 2613 parmDeclType = Context.getPointerType(parmDeclType); 2614 2615 ParmVarDecl *New = ParmVarDecl::Create(Context, CurContext, 2616 D.getIdentifierLoc(), II, 2617 parmDeclType, StorageClass, 2618 0); 2619 2620 if (D.getInvalidType()) 2621 New->setInvalidDecl(); 2622 2623 // Parameter declarators cannot be qualified (C++ [dcl.meaning]p1). 2624 if (D.getCXXScopeSpec().isSet()) { 2625 Diag(D.getIdentifierLoc(), diag::err_qualified_param_declarator) 2626 << D.getCXXScopeSpec().getRange(); 2627 New->setInvalidDecl(); 2628 } 2629 2630 // Add the parameter declaration into this scope. 2631 S->AddDecl(New); 2632 if (II) 2633 IdResolver.AddDecl(New); 2634 2635 ProcessDeclAttributes(New, D); 2636 return New; 2637 2638} 2639 2640void Sema::ActOnFinishKNRParamDeclarations(Scope *S, Declarator &D) { 2641 assert(D.getTypeObject(0).Kind == DeclaratorChunk::Function && 2642 "Not a function declarator!"); 2643 DeclaratorChunk::FunctionTypeInfo &FTI = D.getTypeObject(0).Fun; 2644 2645 // Verify 6.9.1p6: 'every identifier in the identifier list shall be declared' 2646 // for a K&R function. 2647 if (!FTI.hasPrototype) { 2648 for (unsigned i = 0, e = FTI.NumArgs; i != e; ++i) { 2649 if (FTI.ArgInfo[i].Param == 0) { 2650 Diag(FTI.ArgInfo[i].IdentLoc, diag::ext_param_not_declared) 2651 << FTI.ArgInfo[i].Ident; 2652 // Implicitly declare the argument as type 'int' for lack of a better 2653 // type. 2654 DeclSpec DS; 2655 const char* PrevSpec; // unused 2656 DS.SetTypeSpecType(DeclSpec::TST_int, FTI.ArgInfo[i].IdentLoc, 2657 PrevSpec); 2658 Declarator ParamD(DS, Declarator::KNRTypeListContext); 2659 ParamD.SetIdentifier(FTI.ArgInfo[i].Ident, FTI.ArgInfo[i].IdentLoc); 2660 FTI.ArgInfo[i].Param = ActOnParamDeclarator(S, ParamD); 2661 } 2662 } 2663 } 2664} 2665 2666Sema::DeclTy *Sema::ActOnStartOfFunctionDef(Scope *FnBodyScope, Declarator &D) { 2667 assert(getCurFunctionDecl() == 0 && "Function parsing confused"); 2668 assert(D.getTypeObject(0).Kind == DeclaratorChunk::Function && 2669 "Not a function declarator!"); 2670 DeclaratorChunk::FunctionTypeInfo &FTI = D.getTypeObject(0).Fun; 2671 2672 if (FTI.hasPrototype) { 2673 // FIXME: Diagnose arguments without names in C. 2674 } 2675 2676 Scope *ParentScope = FnBodyScope->getParent(); 2677 2678 return ActOnStartOfFunctionDef(FnBodyScope, 2679 ActOnDeclarator(ParentScope, D, 0, 2680 /*IsFunctionDefinition=*/true)); 2681} 2682 2683Sema::DeclTy *Sema::ActOnStartOfFunctionDef(Scope *FnBodyScope, DeclTy *D) { 2684 Decl *decl = static_cast<Decl*>(D); 2685 FunctionDecl *FD = cast<FunctionDecl>(decl); 2686 2687 // See if this is a redefinition. 2688 const FunctionDecl *Definition; 2689 if (FD->getBody(Definition)) { 2690 Diag(FD->getLocation(), diag::err_redefinition) << FD->getDeclName(); 2691 Diag(Definition->getLocation(), diag::note_previous_definition); 2692 } 2693 2694 PushDeclContext(FnBodyScope, FD); 2695 2696 // Check the validity of our function parameters 2697 CheckParmsForFunctionDef(FD); 2698 2699 // Introduce our parameters into the function scope 2700 for (unsigned p = 0, NumParams = FD->getNumParams(); p < NumParams; ++p) { 2701 ParmVarDecl *Param = FD->getParamDecl(p); 2702 Param->setOwningFunction(FD); 2703 2704 // If this has an identifier, add it to the scope stack. 2705 if (Param->getIdentifier()) 2706 PushOnScopeChains(Param, FnBodyScope); 2707 } 2708 2709 // Checking attributes of current function definition 2710 // dllimport attribute. 2711 if (FD->getAttr<DLLImportAttr>() && (!FD->getAttr<DLLExportAttr>())) { 2712 // dllimport attribute cannot be applied to definition. 2713 if (!(FD->getAttr<DLLImportAttr>())->isInherited()) { 2714 Diag(FD->getLocation(), 2715 diag::err_attribute_can_be_applied_only_to_symbol_declaration) 2716 << "dllimport"; 2717 FD->setInvalidDecl(); 2718 return FD; 2719 } else { 2720 // If a symbol previously declared dllimport is later defined, the 2721 // attribute is ignored in subsequent references, and a warning is 2722 // emitted. 2723 Diag(FD->getLocation(), 2724 diag::warn_redeclaration_without_attribute_prev_attribute_ignored) 2725 << FD->getNameAsCString() << "dllimport"; 2726 } 2727 } 2728 return FD; 2729} 2730 2731Sema::DeclTy *Sema::ActOnFinishFunctionBody(DeclTy *D, StmtArg BodyArg) { 2732 Decl *dcl = static_cast<Decl *>(D); 2733 Stmt *Body = static_cast<Stmt*>(BodyArg.release()); 2734 if (FunctionDecl *FD = dyn_cast_or_null<FunctionDecl>(dcl)) { 2735 FD->setBody(Body); 2736 assert(FD == getCurFunctionDecl() && "Function parsing confused"); 2737 } else if (ObjCMethodDecl *MD = dyn_cast_or_null<ObjCMethodDecl>(dcl)) { 2738 MD->setBody((Stmt*)Body); 2739 } else 2740 return 0; 2741 PopDeclContext(); 2742 // Verify and clean out per-function state. 2743 2744 // Check goto/label use. 2745 for (llvm::DenseMap<IdentifierInfo*, LabelStmt*>::iterator 2746 I = LabelMap.begin(), E = LabelMap.end(); I != E; ++I) { 2747 // Verify that we have no forward references left. If so, there was a goto 2748 // or address of a label taken, but no definition of it. Label fwd 2749 // definitions are indicated with a null substmt. 2750 if (I->second->getSubStmt() == 0) { 2751 LabelStmt *L = I->second; 2752 // Emit error. 2753 Diag(L->getIdentLoc(), diag::err_undeclared_label_use) << L->getName(); 2754 2755 // At this point, we have gotos that use the bogus label. Stitch it into 2756 // the function body so that they aren't leaked and that the AST is well 2757 // formed. 2758 if (Body) { 2759 L->setSubStmt(new NullStmt(L->getIdentLoc())); 2760 cast<CompoundStmt>(Body)->push_back(L); 2761 } else { 2762 // The whole function wasn't parsed correctly, just delete this. 2763 delete L; 2764 } 2765 } 2766 } 2767 LabelMap.clear(); 2768 2769 return D; 2770} 2771 2772/// ImplicitlyDefineFunction - An undeclared identifier was used in a function 2773/// call, forming a call to an implicitly defined function (per C99 6.5.1p2). 2774NamedDecl *Sema::ImplicitlyDefineFunction(SourceLocation Loc, 2775 IdentifierInfo &II, Scope *S) { 2776 // Extension in C99. Legal in C90, but warn about it. 2777 if (getLangOptions().C99) 2778 Diag(Loc, diag::ext_implicit_function_decl) << &II; 2779 else 2780 Diag(Loc, diag::warn_implicit_function_decl) << &II; 2781 2782 // FIXME: handle stuff like: 2783 // void foo() { extern float X(); } 2784 // void bar() { X(); } <-- implicit decl for X in another scope. 2785 2786 // Set a Declarator for the implicit definition: int foo(); 2787 const char *Dummy; 2788 DeclSpec DS; 2789 bool Error = DS.SetTypeSpecType(DeclSpec::TST_int, Loc, Dummy); 2790 Error = Error; // Silence warning. 2791 assert(!Error && "Error setting up implicit decl!"); 2792 Declarator D(DS, Declarator::BlockContext); 2793 D.AddTypeInfo(DeclaratorChunk::getFunction(false, false, 0, 0, 0, Loc, D)); 2794 D.SetIdentifier(&II, Loc); 2795 2796 // Insert this function into translation-unit scope. 2797 2798 DeclContext *PrevDC = CurContext; 2799 CurContext = Context.getTranslationUnitDecl(); 2800 2801 FunctionDecl *FD = 2802 dyn_cast<FunctionDecl>(static_cast<Decl*>(ActOnDeclarator(TUScope, D, 0))); 2803 FD->setImplicit(); 2804 2805 CurContext = PrevDC; 2806 2807 return FD; 2808} 2809 2810 2811TypedefDecl *Sema::ParseTypedefDecl(Scope *S, Declarator &D, QualType T, 2812 Decl *LastDeclarator) { 2813 assert(D.getIdentifier() && "Wrong callback for declspec without declarator"); 2814 assert(!T.isNull() && "GetTypeForDeclarator() returned null type"); 2815 2816 // Scope manipulation handled by caller. 2817 TypedefDecl *NewTD = TypedefDecl::Create(Context, CurContext, 2818 D.getIdentifierLoc(), 2819 D.getIdentifier(), 2820 T); 2821 NewTD->setNextDeclarator(LastDeclarator); 2822 if (D.getInvalidType()) 2823 NewTD->setInvalidDecl(); 2824 return NewTD; 2825} 2826 2827/// ActOnTag - This is invoked when we see 'struct foo' or 'struct {'. In the 2828/// former case, Name will be non-null. In the later case, Name will be null. 2829/// TagSpec indicates what kind of tag this is. TK indicates whether this is a 2830/// reference/declaration/definition of a tag. 2831Sema::DeclTy *Sema::ActOnTag(Scope *S, unsigned TagSpec, TagKind TK, 2832 SourceLocation KWLoc, const CXXScopeSpec &SS, 2833 IdentifierInfo *Name, SourceLocation NameLoc, 2834 AttributeList *Attr, 2835 MultiTemplateParamsArg TemplateParameterLists) { 2836 // If this is not a definition, it must have a name. 2837 assert((Name != 0 || TK == TK_Definition) && 2838 "Nameless record must be a definition!"); 2839 2840 TagDecl::TagKind Kind; 2841 switch (TagSpec) { 2842 default: assert(0 && "Unknown tag type!"); 2843 case DeclSpec::TST_struct: Kind = TagDecl::TK_struct; break; 2844 case DeclSpec::TST_union: Kind = TagDecl::TK_union; break; 2845 case DeclSpec::TST_class: Kind = TagDecl::TK_class; break; 2846 case DeclSpec::TST_enum: Kind = TagDecl::TK_enum; break; 2847 } 2848 2849 DeclContext *SearchDC = CurContext; 2850 DeclContext *DC = CurContext; 2851 DeclContext *LexicalContext = CurContext; 2852 Decl *PrevDecl = 0; 2853 2854 bool Invalid = false; 2855 2856 if (Name && SS.isNotEmpty()) { 2857 // We have a nested-name tag ('struct foo::bar'). 2858 2859 // Check for invalid 'foo::'. 2860 if (SS.isInvalid()) { 2861 Name = 0; 2862 goto CreateNewDecl; 2863 } 2864 2865 DC = static_cast<DeclContext*>(SS.getScopeRep()); 2866 // Look-up name inside 'foo::'. 2867 PrevDecl = dyn_cast_or_null<TagDecl>(LookupDecl(Name, Decl::IDNS_Tag,S,DC) 2868 .getAsDecl()); 2869 2870 // A tag 'foo::bar' must already exist. 2871 if (PrevDecl == 0) { 2872 Diag(NameLoc, diag::err_not_tag_in_scope) << Name << SS.getRange(); 2873 Name = 0; 2874 goto CreateNewDecl; 2875 } 2876 } else if (Name) { 2877 // If this is a named struct, check to see if there was a previous forward 2878 // declaration or definition. 2879 PrevDecl = dyn_cast_or_null<NamedDecl>(LookupDecl(Name, Decl::IDNS_Tag,S) 2880 .getAsDecl()); 2881 2882 if (!getLangOptions().CPlusPlus && TK != TK_Reference) { 2883 // FIXME: This makes sure that we ignore the contexts associated 2884 // with C structs, unions, and enums when looking for a matching 2885 // tag declaration or definition. See the similar lookup tweak 2886 // in Sema::LookupDecl; is there a better way to deal with this? 2887 while (isa<RecordDecl>(SearchDC) || isa<EnumDecl>(SearchDC)) 2888 SearchDC = SearchDC->getParent(); 2889 } 2890 } 2891 2892 if (PrevDecl && PrevDecl->isTemplateParameter()) { 2893 // Maybe we will complain about the shadowed template parameter. 2894 DiagnoseTemplateParameterShadow(NameLoc, PrevDecl); 2895 // Just pretend that we didn't see the previous declaration. 2896 PrevDecl = 0; 2897 } 2898 2899 if (PrevDecl) { 2900 if (TagDecl *PrevTagDecl = dyn_cast<TagDecl>(PrevDecl)) { 2901 // If this is a use of a previous tag, or if the tag is already declared 2902 // in the same scope (so that the definition/declaration completes or 2903 // rementions the tag), reuse the decl. 2904 if (TK == TK_Reference || isDeclInScope(PrevDecl, SearchDC, S)) { 2905 // Make sure that this wasn't declared as an enum and now used as a 2906 // struct or something similar. 2907 if (PrevTagDecl->getTagKind() != Kind) { 2908 Diag(KWLoc, diag::err_use_with_wrong_tag) << Name; 2909 Diag(PrevDecl->getLocation(), diag::note_previous_use); 2910 // Recover by making this an anonymous redefinition. 2911 Name = 0; 2912 PrevDecl = 0; 2913 Invalid = true; 2914 } else { 2915 // If this is a use, just return the declaration we found. 2916 2917 // FIXME: In the future, return a variant or some other clue 2918 // for the consumer of this Decl to know it doesn't own it. 2919 // For our current ASTs this shouldn't be a problem, but will 2920 // need to be changed with DeclGroups. 2921 if (TK == TK_Reference) 2922 return PrevDecl; 2923 2924 // Diagnose attempts to redefine a tag. 2925 if (TK == TK_Definition) { 2926 if (TagDecl *Def = PrevTagDecl->getDefinition(Context)) { 2927 Diag(NameLoc, diag::err_redefinition) << Name; 2928 Diag(Def->getLocation(), diag::note_previous_definition); 2929 // If this is a redefinition, recover by making this 2930 // struct be anonymous, which will make any later 2931 // references get the previous definition. 2932 Name = 0; 2933 PrevDecl = 0; 2934 Invalid = true; 2935 } else { 2936 // If the type is currently being defined, complain 2937 // about a nested redefinition. 2938 TagType *Tag = cast<TagType>(Context.getTagDeclType(PrevTagDecl)); 2939 if (Tag->isBeingDefined()) { 2940 Diag(NameLoc, diag::err_nested_redefinition) << Name; 2941 Diag(PrevTagDecl->getLocation(), 2942 diag::note_previous_definition); 2943 Name = 0; 2944 PrevDecl = 0; 2945 Invalid = true; 2946 } 2947 } 2948 2949 // Okay, this is definition of a previously declared or referenced 2950 // tag PrevDecl. We're going to create a new Decl for it. 2951 } 2952 } 2953 // If we get here we have (another) forward declaration or we 2954 // have a definition. Just create a new decl. 2955 } else { 2956 // If we get here, this is a definition of a new tag type in a nested 2957 // scope, e.g. "struct foo; void bar() { struct foo; }", just create a 2958 // new decl/type. We set PrevDecl to NULL so that the entities 2959 // have distinct types. 2960 PrevDecl = 0; 2961 } 2962 // If we get here, we're going to create a new Decl. If PrevDecl 2963 // is non-NULL, it's a definition of the tag declared by 2964 // PrevDecl. If it's NULL, we have a new definition. 2965 } else { 2966 // PrevDecl is a namespace, template, or anything else 2967 // that lives in the IDNS_Tag identifier namespace. 2968 if (isDeclInScope(PrevDecl, SearchDC, S)) { 2969 // The tag name clashes with a namespace name, issue an error and 2970 // recover by making this tag be anonymous. 2971 Diag(NameLoc, diag::err_redefinition_different_kind) << Name; 2972 Diag(PrevDecl->getLocation(), diag::note_previous_definition); 2973 Name = 0; 2974 PrevDecl = 0; 2975 Invalid = true; 2976 } else { 2977 // The existing declaration isn't relevant to us; we're in a 2978 // new scope, so clear out the previous declaration. 2979 PrevDecl = 0; 2980 } 2981 } 2982 } else if (TK == TK_Reference && SS.isEmpty() && Name && 2983 (Kind != TagDecl::TK_enum)) { 2984 // C++ [basic.scope.pdecl]p5: 2985 // -- for an elaborated-type-specifier of the form 2986 // 2987 // class-key identifier 2988 // 2989 // if the elaborated-type-specifier is used in the 2990 // decl-specifier-seq or parameter-declaration-clause of a 2991 // function defined in namespace scope, the identifier is 2992 // declared as a class-name in the namespace that contains 2993 // the declaration; otherwise, except as a friend 2994 // declaration, the identifier is declared in the smallest 2995 // non-class, non-function-prototype scope that contains the 2996 // declaration. 2997 // 2998 // C99 6.7.2.3p8 has a similar (but not identical!) provision for 2999 // C structs and unions. 3000 3001 // Find the context where we'll be declaring the tag. 3002 // FIXME: We would like to maintain the current DeclContext as the 3003 // lexical context, 3004 while (DC->isRecord()) 3005 DC = DC->getParent(); 3006 LexicalContext = DC; 3007 3008 // Find the scope where we'll be declaring the tag. 3009 while (S->isClassScope() || 3010 (getLangOptions().CPlusPlus && S->isFunctionPrototypeScope()) || 3011 ((S->getFlags() & Scope::DeclScope) == 0) || 3012 (S->getEntity() && 3013 ((DeclContext *)S->getEntity())->isTransparentContext())) 3014 S = S->getParent(); 3015 } 3016 3017CreateNewDecl: 3018 3019 // If there is an identifier, use the location of the identifier as the 3020 // location of the decl, otherwise use the location of the struct/union 3021 // keyword. 3022 SourceLocation Loc = NameLoc.isValid() ? NameLoc : KWLoc; 3023 3024 // Otherwise, create a new declaration. If there is a previous 3025 // declaration of the same entity, the two will be linked via 3026 // PrevDecl. 3027 TagDecl *New; 3028 3029 if (Kind == TagDecl::TK_enum) { 3030 // FIXME: Tag decls should be chained to any simultaneous vardecls, e.g.: 3031 // enum X { A, B, C } D; D should chain to X. 3032 New = EnumDecl::Create(Context, DC, Loc, Name, 3033 cast_or_null<EnumDecl>(PrevDecl)); 3034 // If this is an undefined enum, warn. 3035 if (TK != TK_Definition) Diag(Loc, diag::ext_forward_ref_enum); 3036 } else { 3037 // struct/union/class 3038 3039 // FIXME: Tag decls should be chained to any simultaneous vardecls, e.g.: 3040 // struct X { int A; } D; D should chain to X. 3041 if (getLangOptions().CPlusPlus) 3042 // FIXME: Look for a way to use RecordDecl for simple structs. 3043 New = CXXRecordDecl::Create(Context, Kind, DC, Loc, Name, 3044 cast_or_null<CXXRecordDecl>(PrevDecl)); 3045 else 3046 New = RecordDecl::Create(Context, Kind, DC, Loc, Name, 3047 cast_or_null<RecordDecl>(PrevDecl)); 3048 } 3049 3050 if (Kind != TagDecl::TK_enum) { 3051 // Handle #pragma pack: if the #pragma pack stack has non-default 3052 // alignment, make up a packed attribute for this decl. These 3053 // attributes are checked when the ASTContext lays out the 3054 // structure. 3055 // 3056 // It is important for implementing the correct semantics that this 3057 // happen here (in act on tag decl). The #pragma pack stack is 3058 // maintained as a result of parser callbacks which can occur at 3059 // many points during the parsing of a struct declaration (because 3060 // the #pragma tokens are effectively skipped over during the 3061 // parsing of the struct). 3062 if (unsigned Alignment = PackContext.getAlignment()) 3063 New->addAttr(new PackedAttr(Alignment * 8)); 3064 } 3065 3066 if (getLangOptions().CPlusPlus && SS.isEmpty() && Name && !Invalid) { 3067 // C++ [dcl.typedef]p3: 3068 // [...] Similarly, in a given scope, a class or enumeration 3069 // shall not be declared with the same name as a typedef-name 3070 // that is declared in that scope and refers to a type other 3071 // than the class or enumeration itself. 3072 LookupResult Lookup = LookupName(S, Name, 3073 LookupCriteria(LookupCriteria::Ordinary, 3074 true, true)); 3075 TypedefDecl *PrevTypedef = 0; 3076 if (Lookup.getKind() == LookupResult::Found) 3077 PrevTypedef = dyn_cast<TypedefDecl>(Lookup.getAsDecl()); 3078 3079 if (PrevTypedef && isDeclInScope(PrevTypedef, SearchDC, S) && 3080 Context.getCanonicalType(Context.getTypeDeclType(PrevTypedef)) != 3081 Context.getCanonicalType(Context.getTypeDeclType(New))) { 3082 Diag(Loc, diag::err_tag_definition_of_typedef) 3083 << Context.getTypeDeclType(New) 3084 << PrevTypedef->getUnderlyingType(); 3085 Diag(PrevTypedef->getLocation(), diag::note_previous_definition); 3086 Invalid = true; 3087 } 3088 } 3089 3090 if (Invalid) 3091 New->setInvalidDecl(); 3092 3093 if (Attr) 3094 ProcessDeclAttributeList(New, Attr); 3095 3096 // If we're declaring or defining a tag in function prototype scope 3097 // in C, note that this type can only be used within the function. 3098 if (Name && S->isFunctionPrototypeScope() && !getLangOptions().CPlusPlus) 3099 Diag(Loc, diag::warn_decl_in_param_list) << Context.getTagDeclType(New); 3100 3101 // Set the lexical context. If the tag has a C++ scope specifier, the 3102 // lexical context will be different from the semantic context. 3103 New->setLexicalDeclContext(LexicalContext); 3104 3105 if (TK == TK_Definition) 3106 New->startDefinition(); 3107 3108 // If this has an identifier, add it to the scope stack. 3109 if (Name) { 3110 S = getNonFieldDeclScope(S); 3111 3112 // Add it to the decl chain. 3113 if (LexicalContext != CurContext) { 3114 // FIXME: PushOnScopeChains should not rely on CurContext! 3115 DeclContext *OldContext = CurContext; 3116 CurContext = LexicalContext; 3117 PushOnScopeChains(New, S); 3118 CurContext = OldContext; 3119 } else 3120 PushOnScopeChains(New, S); 3121 } else { 3122 LexicalContext->addDecl(New); 3123 } 3124 3125 return New; 3126} 3127 3128void Sema::ActOnTagStartDefinition(Scope *S, DeclTy *TagD) { 3129 TagDecl *Tag = cast<TagDecl>((Decl *)TagD); 3130 3131 // Enter the tag context. 3132 PushDeclContext(S, Tag); 3133 3134 if (CXXRecordDecl *Record = dyn_cast<CXXRecordDecl>(Tag)) { 3135 FieldCollector->StartClass(); 3136 3137 if (Record->getIdentifier()) { 3138 // C++ [class]p2: 3139 // [...] The class-name is also inserted into the scope of the 3140 // class itself; this is known as the injected-class-name. For 3141 // purposes of access checking, the injected-class-name is treated 3142 // as if it were a public member name. 3143 RecordDecl *InjectedClassName 3144 = CXXRecordDecl::Create(Context, Record->getTagKind(), 3145 CurContext, Record->getLocation(), 3146 Record->getIdentifier(), Record); 3147 InjectedClassName->setImplicit(); 3148 PushOnScopeChains(InjectedClassName, S); 3149 } 3150 } 3151} 3152 3153void Sema::ActOnTagFinishDefinition(Scope *S, DeclTy *TagD) { 3154 TagDecl *Tag = cast<TagDecl>((Decl *)TagD); 3155 3156 if (isa<CXXRecordDecl>(Tag)) 3157 FieldCollector->FinishClass(); 3158 3159 // Exit this scope of this tag's definition. 3160 PopDeclContext(); 3161 3162 // Notify the consumer that we've defined a tag. 3163 Consumer.HandleTagDeclDefinition(Tag); 3164} 3165 3166/// TryToFixInvalidVariablyModifiedType - Helper method to turn variable array 3167/// types into constant array types in certain situations which would otherwise 3168/// be errors (for GCC compatibility). 3169static QualType TryToFixInvalidVariablyModifiedType(QualType T, 3170 ASTContext &Context) { 3171 // This method tries to turn a variable array into a constant 3172 // array even when the size isn't an ICE. This is necessary 3173 // for compatibility with code that depends on gcc's buggy 3174 // constant expression folding, like struct {char x[(int)(char*)2];} 3175 const VariableArrayType* VLATy = dyn_cast<VariableArrayType>(T); 3176 if (!VLATy) return QualType(); 3177 3178 Expr::EvalResult EvalResult; 3179 if (!VLATy->getSizeExpr() || 3180 !VLATy->getSizeExpr()->Evaluate(EvalResult, Context)) 3181 return QualType(); 3182 3183 assert(EvalResult.Val.isInt() && "Size expressions must be integers!"); 3184 llvm::APSInt &Res = EvalResult.Val.getInt(); 3185 if (Res > llvm::APSInt(Res.getBitWidth(), Res.isUnsigned())) 3186 return Context.getConstantArrayType(VLATy->getElementType(), 3187 Res, ArrayType::Normal, 0); 3188 return QualType(); 3189} 3190 3191bool Sema::VerifyBitField(SourceLocation FieldLoc, IdentifierInfo *FieldName, 3192 QualType FieldTy, const Expr *BitWidth) { 3193 // FIXME: 6.7.2.1p4 - verify the field type. 3194 3195 llvm::APSInt Value; 3196 if (VerifyIntegerConstantExpression(BitWidth, &Value)) 3197 return true; 3198 3199 // Zero-width bitfield is ok for anonymous field. 3200 if (Value == 0 && FieldName) 3201 return Diag(FieldLoc, diag::err_bitfield_has_zero_width) << FieldName; 3202 3203 if (Value.isNegative()) 3204 return Diag(FieldLoc, diag::err_bitfield_has_negative_width) << FieldName; 3205 3206 uint64_t TypeSize = Context.getTypeSize(FieldTy); 3207 // FIXME: We won't need the 0 size once we check that the field type is valid. 3208 if (TypeSize && Value.getZExtValue() > TypeSize) 3209 return Diag(FieldLoc, diag::err_bitfield_width_exceeds_type_size) 3210 << FieldName << (unsigned)TypeSize; 3211 3212 return false; 3213} 3214 3215/// ActOnField - Each field of a struct/union/class is passed into this in order 3216/// to create a FieldDecl object for it. 3217Sema::DeclTy *Sema::ActOnField(Scope *S, DeclTy *TagD, 3218 SourceLocation DeclStart, 3219 Declarator &D, ExprTy *BitfieldWidth) { 3220 IdentifierInfo *II = D.getIdentifier(); 3221 Expr *BitWidth = (Expr*)BitfieldWidth; 3222 SourceLocation Loc = DeclStart; 3223 RecordDecl *Record = (RecordDecl *)TagD; 3224 if (II) Loc = D.getIdentifierLoc(); 3225 3226 // FIXME: Unnamed fields can be handled in various different ways, for 3227 // example, unnamed unions inject all members into the struct namespace! 3228 3229 QualType T = GetTypeForDeclarator(D, S); 3230 assert(!T.isNull() && "GetTypeForDeclarator() returned null type"); 3231 bool InvalidDecl = false; 3232 3233 // C99 6.7.2.1p8: A member of a structure or union may have any type other 3234 // than a variably modified type. 3235 if (T->isVariablyModifiedType()) { 3236 QualType FixedTy = TryToFixInvalidVariablyModifiedType(T, Context); 3237 if (!FixedTy.isNull()) { 3238 Diag(Loc, diag::warn_illegal_constant_array_size); 3239 T = FixedTy; 3240 } else { 3241 Diag(Loc, diag::err_typecheck_field_variable_size); 3242 T = Context.IntTy; 3243 InvalidDecl = true; 3244 } 3245 } 3246 3247 if (BitWidth) { 3248 if (VerifyBitField(Loc, II, T, BitWidth)) 3249 InvalidDecl = true; 3250 } else { 3251 // Not a bitfield. 3252 3253 // validate II. 3254 3255 } 3256 3257 // FIXME: Chain fielddecls together. 3258 FieldDecl *NewFD; 3259 3260 NewFD = FieldDecl::Create(Context, Record, 3261 Loc, II, T, BitWidth, 3262 D.getDeclSpec().getStorageClassSpec() == 3263 DeclSpec::SCS_mutable); 3264 3265 if (II) { 3266 Decl *PrevDecl 3267 = LookupDecl(II, Decl::IDNS_Member, S, 0, false); 3268 if (PrevDecl && isDeclInScope(PrevDecl, CurContext, S) 3269 && !isa<TagDecl>(PrevDecl)) { 3270 Diag(Loc, diag::err_duplicate_member) << II; 3271 Diag(PrevDecl->getLocation(), diag::note_previous_declaration); 3272 NewFD->setInvalidDecl(); 3273 Record->setInvalidDecl(); 3274 } 3275 } 3276 3277 if (getLangOptions().CPlusPlus) { 3278 CheckExtraCXXDefaultArguments(D); 3279 if (!T->isPODType()) 3280 cast<CXXRecordDecl>(Record)->setPOD(false); 3281 } 3282 3283 ProcessDeclAttributes(NewFD, D); 3284 3285 if (D.getInvalidType() || InvalidDecl) 3286 NewFD->setInvalidDecl(); 3287 3288 if (II) { 3289 PushOnScopeChains(NewFD, S); 3290 } else 3291 Record->addDecl(NewFD); 3292 3293 return NewFD; 3294} 3295 3296/// TranslateIvarVisibility - Translate visibility from a token ID to an 3297/// AST enum value. 3298static ObjCIvarDecl::AccessControl 3299TranslateIvarVisibility(tok::ObjCKeywordKind ivarVisibility) { 3300 switch (ivarVisibility) { 3301 default: assert(0 && "Unknown visitibility kind"); 3302 case tok::objc_private: return ObjCIvarDecl::Private; 3303 case tok::objc_public: return ObjCIvarDecl::Public; 3304 case tok::objc_protected: return ObjCIvarDecl::Protected; 3305 case tok::objc_package: return ObjCIvarDecl::Package; 3306 } 3307} 3308 3309/// ActOnIvar - Each ivar field of an objective-c class is passed into this 3310/// in order to create an IvarDecl object for it. 3311Sema::DeclTy *Sema::ActOnIvar(Scope *S, 3312 SourceLocation DeclStart, 3313 Declarator &D, ExprTy *BitfieldWidth, 3314 tok::ObjCKeywordKind Visibility) { 3315 3316 IdentifierInfo *II = D.getIdentifier(); 3317 Expr *BitWidth = (Expr*)BitfieldWidth; 3318 SourceLocation Loc = DeclStart; 3319 if (II) Loc = D.getIdentifierLoc(); 3320 3321 // FIXME: Unnamed fields can be handled in various different ways, for 3322 // example, unnamed unions inject all members into the struct namespace! 3323 3324 QualType T = GetTypeForDeclarator(D, S); 3325 assert(!T.isNull() && "GetTypeForDeclarator() returned null type"); 3326 bool InvalidDecl = false; 3327 3328 if (BitWidth) { 3329 // TODO: Validate. 3330 //printf("WARNING: BITFIELDS IGNORED!\n"); 3331 3332 // 6.7.2.1p3 3333 // 6.7.2.1p4 3334 3335 } else { 3336 // Not a bitfield. 3337 3338 // validate II. 3339 3340 } 3341 3342 // C99 6.7.2.1p8: A member of a structure or union may have any type other 3343 // than a variably modified type. 3344 if (T->isVariablyModifiedType()) { 3345 Diag(Loc, diag::err_typecheck_ivar_variable_size); 3346 InvalidDecl = true; 3347 } 3348 3349 // Get the visibility (access control) for this ivar. 3350 ObjCIvarDecl::AccessControl ac = 3351 Visibility != tok::objc_not_keyword ? TranslateIvarVisibility(Visibility) 3352 : ObjCIvarDecl::None; 3353 3354 // Construct the decl. 3355 ObjCIvarDecl *NewID = ObjCIvarDecl::Create(Context, Loc, II, T, ac, 3356 (Expr *)BitfieldWidth); 3357 3358 if (II) { 3359 Decl *PrevDecl 3360 = LookupDecl(II, Decl::IDNS_Member, S, 0, false); 3361 if (PrevDecl && isDeclInScope(PrevDecl, CurContext, S) 3362 && !isa<TagDecl>(PrevDecl)) { 3363 Diag(Loc, diag::err_duplicate_member) << II; 3364 Diag(PrevDecl->getLocation(), diag::note_previous_declaration); 3365 NewID->setInvalidDecl(); 3366 } 3367 } 3368 3369 // Process attributes attached to the ivar. 3370 ProcessDeclAttributes(NewID, D); 3371 3372 if (D.getInvalidType() || InvalidDecl) 3373 NewID->setInvalidDecl(); 3374 3375 if (II) { 3376 // FIXME: When interfaces are DeclContexts, we'll need to add 3377 // these to the interface. 3378 S->AddDecl(NewID); 3379 IdResolver.AddDecl(NewID); 3380 } 3381 3382 return NewID; 3383} 3384 3385void Sema::ActOnFields(Scope* S, 3386 SourceLocation RecLoc, DeclTy *RecDecl, 3387 DeclTy **Fields, unsigned NumFields, 3388 SourceLocation LBrac, SourceLocation RBrac, 3389 AttributeList *Attr) { 3390 Decl *EnclosingDecl = static_cast<Decl*>(RecDecl); 3391 assert(EnclosingDecl && "missing record or interface decl"); 3392 RecordDecl *Record = dyn_cast<RecordDecl>(EnclosingDecl); 3393 3394 // Verify that all the fields are okay. 3395 unsigned NumNamedMembers = 0; 3396 llvm::SmallVector<FieldDecl*, 32> RecFields; 3397 3398 for (unsigned i = 0; i != NumFields; ++i) { 3399 FieldDecl *FD = cast_or_null<FieldDecl>(static_cast<Decl*>(Fields[i])); 3400 assert(FD && "missing field decl"); 3401 3402 // Get the type for the field. 3403 Type *FDTy = FD->getType().getTypePtr(); 3404 3405 if (!FD->isAnonymousStructOrUnion()) { 3406 // Remember all fields written by the user. 3407 RecFields.push_back(FD); 3408 } 3409 3410 // C99 6.7.2.1p2 - A field may not be a function type. 3411 if (FDTy->isFunctionType()) { 3412 Diag(FD->getLocation(), diag::err_field_declared_as_function) 3413 << FD->getDeclName(); 3414 FD->setInvalidDecl(); 3415 EnclosingDecl->setInvalidDecl(); 3416 continue; 3417 } 3418 // C99 6.7.2.1p2 - A field may not be an incomplete type except... 3419 if (FDTy->isIncompleteType()) { 3420 if (!Record) { // Incomplete ivar type is always an error. 3421 DiagnoseIncompleteType(FD->getLocation(), FD->getType(), 3422 diag::err_field_incomplete); 3423 FD->setInvalidDecl(); 3424 EnclosingDecl->setInvalidDecl(); 3425 continue; 3426 } 3427 if (i != NumFields-1 || // ... that the last member ... 3428 !Record->isStruct() || // ... of a structure ... 3429 !FDTy->isArrayType()) { //... may have incomplete array type. 3430 DiagnoseIncompleteType(FD->getLocation(), FD->getType(), 3431 diag::err_field_incomplete); 3432 FD->setInvalidDecl(); 3433 EnclosingDecl->setInvalidDecl(); 3434 continue; 3435 } 3436 if (NumNamedMembers < 1) { //... must have more than named member ... 3437 Diag(FD->getLocation(), diag::err_flexible_array_empty_struct) 3438 << FD->getDeclName(); 3439 FD->setInvalidDecl(); 3440 EnclosingDecl->setInvalidDecl(); 3441 continue; 3442 } 3443 // Okay, we have a legal flexible array member at the end of the struct. 3444 if (Record) 3445 Record->setHasFlexibleArrayMember(true); 3446 } 3447 /// C99 6.7.2.1p2 - a struct ending in a flexible array member cannot be the 3448 /// field of another structure or the element of an array. 3449 if (const RecordType *FDTTy = FDTy->getAsRecordType()) { 3450 if (FDTTy->getDecl()->hasFlexibleArrayMember()) { 3451 // If this is a member of a union, then entire union becomes "flexible". 3452 if (Record && Record->isUnion()) { 3453 Record->setHasFlexibleArrayMember(true); 3454 } else { 3455 // If this is a struct/class and this is not the last element, reject 3456 // it. Note that GCC supports variable sized arrays in the middle of 3457 // structures. 3458 if (i != NumFields-1) { 3459 Diag(FD->getLocation(), diag::err_variable_sized_type_in_struct) 3460 << FD->getDeclName(); 3461 FD->setInvalidDecl(); 3462 EnclosingDecl->setInvalidDecl(); 3463 continue; 3464 } 3465 // We support flexible arrays at the end of structs in other structs 3466 // as an extension. 3467 Diag(FD->getLocation(), diag::ext_flexible_array_in_struct) 3468 << FD->getDeclName(); 3469 if (Record) 3470 Record->setHasFlexibleArrayMember(true); 3471 } 3472 } 3473 } 3474 /// A field cannot be an Objective-c object 3475 if (FDTy->isObjCInterfaceType()) { 3476 Diag(FD->getLocation(), diag::err_statically_allocated_object) 3477 << FD->getDeclName(); 3478 FD->setInvalidDecl(); 3479 EnclosingDecl->setInvalidDecl(); 3480 continue; 3481 } 3482 // Keep track of the number of named members. 3483 if (FD->getIdentifier()) 3484 ++NumNamedMembers; 3485 } 3486 3487 // Okay, we successfully defined 'Record'. 3488 if (Record) { 3489 Record->completeDefinition(Context); 3490 } else { 3491 ObjCIvarDecl **ClsFields = reinterpret_cast<ObjCIvarDecl**>(&RecFields[0]); 3492 if (ObjCInterfaceDecl *ID = dyn_cast<ObjCInterfaceDecl>(EnclosingDecl)) { 3493 ID->addInstanceVariablesToClass(ClsFields, RecFields.size(), RBrac); 3494 // Must enforce the rule that ivars in the base classes may not be 3495 // duplicates. 3496 if (ID->getSuperClass()) { 3497 for (ObjCInterfaceDecl::ivar_iterator IVI = ID->ivar_begin(), 3498 IVE = ID->ivar_end(); IVI != IVE; ++IVI) { 3499 ObjCIvarDecl* Ivar = (*IVI); 3500 IdentifierInfo *II = Ivar->getIdentifier(); 3501 ObjCIvarDecl* prevIvar = ID->getSuperClass()->FindIvarDeclaration(II); 3502 if (prevIvar) { 3503 Diag(Ivar->getLocation(), diag::err_duplicate_member) << II; 3504 Diag(prevIvar->getLocation(), diag::note_previous_declaration); 3505 } 3506 } 3507 } 3508 } 3509 else if (ObjCImplementationDecl *IMPDecl = 3510 dyn_cast<ObjCImplementationDecl>(EnclosingDecl)) { 3511 assert(IMPDecl && "ActOnFields - missing ObjCImplementationDecl"); 3512 IMPDecl->ObjCAddInstanceVariablesToClassImpl(ClsFields, RecFields.size()); 3513 CheckImplementationIvars(IMPDecl, ClsFields, RecFields.size(), RBrac); 3514 } 3515 } 3516 3517 if (Attr) 3518 ProcessDeclAttributeList(Record, Attr); 3519} 3520 3521Sema::DeclTy *Sema::ActOnEnumConstant(Scope *S, DeclTy *theEnumDecl, 3522 DeclTy *lastEnumConst, 3523 SourceLocation IdLoc, IdentifierInfo *Id, 3524 SourceLocation EqualLoc, ExprTy *val) { 3525 EnumDecl *TheEnumDecl = cast<EnumDecl>(static_cast<Decl*>(theEnumDecl)); 3526 EnumConstantDecl *LastEnumConst = 3527 cast_or_null<EnumConstantDecl>(static_cast<Decl*>(lastEnumConst)); 3528 Expr *Val = static_cast<Expr*>(val); 3529 3530 // The scope passed in may not be a decl scope. Zip up the scope tree until 3531 // we find one that is. 3532 S = getNonFieldDeclScope(S); 3533 3534 // Verify that there isn't already something declared with this name in this 3535 // scope. 3536 Decl *PrevDecl = LookupDecl(Id, Decl::IDNS_Ordinary, S); 3537 if (PrevDecl && PrevDecl->isTemplateParameter()) { 3538 // Maybe we will complain about the shadowed template parameter. 3539 DiagnoseTemplateParameterShadow(IdLoc, PrevDecl); 3540 // Just pretend that we didn't see the previous declaration. 3541 PrevDecl = 0; 3542 } 3543 3544 if (PrevDecl) { 3545 // When in C++, we may get a TagDecl with the same name; in this case the 3546 // enum constant will 'hide' the tag. 3547 assert((getLangOptions().CPlusPlus || !isa<TagDecl>(PrevDecl)) && 3548 "Received TagDecl when not in C++!"); 3549 if (!isa<TagDecl>(PrevDecl) && isDeclInScope(PrevDecl, CurContext, S)) { 3550 if (isa<EnumConstantDecl>(PrevDecl)) 3551 Diag(IdLoc, diag::err_redefinition_of_enumerator) << Id; 3552 else 3553 Diag(IdLoc, diag::err_redefinition) << Id; 3554 Diag(PrevDecl->getLocation(), diag::note_previous_definition); 3555 delete Val; 3556 return 0; 3557 } 3558 } 3559 3560 llvm::APSInt EnumVal(32); 3561 QualType EltTy; 3562 if (Val) { 3563 // Make sure to promote the operand type to int. 3564 UsualUnaryConversions(Val); 3565 3566 // C99 6.7.2.2p2: Make sure we have an integer constant expression. 3567 SourceLocation ExpLoc; 3568 if (VerifyIntegerConstantExpression(Val, &EnumVal)) { 3569 delete Val; 3570 Val = 0; // Just forget about it. 3571 } else { 3572 EltTy = Val->getType(); 3573 } 3574 } 3575 3576 if (!Val) { 3577 if (LastEnumConst) { 3578 // Assign the last value + 1. 3579 EnumVal = LastEnumConst->getInitVal(); 3580 ++EnumVal; 3581 3582 // Check for overflow on increment. 3583 if (EnumVal < LastEnumConst->getInitVal()) 3584 Diag(IdLoc, diag::warn_enum_value_overflow); 3585 3586 EltTy = LastEnumConst->getType(); 3587 } else { 3588 // First value, set to zero. 3589 EltTy = Context.IntTy; 3590 EnumVal.zextOrTrunc(static_cast<uint32_t>(Context.getTypeSize(EltTy))); 3591 } 3592 } 3593 3594 EnumConstantDecl *New = 3595 EnumConstantDecl::Create(Context, TheEnumDecl, IdLoc, Id, EltTy, 3596 Val, EnumVal); 3597 3598 // Register this decl in the current scope stack. 3599 PushOnScopeChains(New, S); 3600 3601 return New; 3602} 3603 3604// FIXME: For consistency with ActOnFields(), we should have the parser 3605// pass in the source location for the left/right braces. 3606void Sema::ActOnEnumBody(SourceLocation EnumLoc, DeclTy *EnumDeclX, 3607 DeclTy **Elements, unsigned NumElements) { 3608 EnumDecl *Enum = cast<EnumDecl>(static_cast<Decl*>(EnumDeclX)); 3609 QualType EnumType = Context.getTypeDeclType(Enum); 3610 3611 // TODO: If the result value doesn't fit in an int, it must be a long or long 3612 // long value. ISO C does not support this, but GCC does as an extension, 3613 // emit a warning. 3614 unsigned IntWidth = Context.Target.getIntWidth(); 3615 3616 // Verify that all the values are okay, compute the size of the values, and 3617 // reverse the list. 3618 unsigned NumNegativeBits = 0; 3619 unsigned NumPositiveBits = 0; 3620 3621 // Keep track of whether all elements have type int. 3622 bool AllElementsInt = true; 3623 3624 for (unsigned i = 0; i != NumElements; ++i) { 3625 EnumConstantDecl *ECD = 3626 cast_or_null<EnumConstantDecl>(static_cast<Decl*>(Elements[i])); 3627 if (!ECD) continue; // Already issued a diagnostic. 3628 3629 // If the enum value doesn't fit in an int, emit an extension warning. 3630 const llvm::APSInt &InitVal = ECD->getInitVal(); 3631 assert(InitVal.getBitWidth() >= IntWidth && 3632 "Should have promoted value to int"); 3633 if (InitVal.getBitWidth() > IntWidth) { 3634 llvm::APSInt V(InitVal); 3635 V.trunc(IntWidth); 3636 V.extend(InitVal.getBitWidth()); 3637 if (V != InitVal) 3638 Diag(ECD->getLocation(), diag::ext_enum_value_not_int) 3639 << InitVal.toString(10); 3640 } 3641 3642 // Keep track of the size of positive and negative values. 3643 if (InitVal.isUnsigned() || InitVal.isNonNegative()) 3644 NumPositiveBits = std::max(NumPositiveBits, 3645 (unsigned)InitVal.getActiveBits()); 3646 else 3647 NumNegativeBits = std::max(NumNegativeBits, 3648 (unsigned)InitVal.getMinSignedBits()); 3649 3650 // Keep track of whether every enum element has type int (very commmon). 3651 if (AllElementsInt) 3652 AllElementsInt = ECD->getType() == Context.IntTy; 3653 } 3654 3655 // Figure out the type that should be used for this enum. 3656 // FIXME: Support attribute(packed) on enums and -fshort-enums. 3657 QualType BestType; 3658 unsigned BestWidth; 3659 3660 if (NumNegativeBits) { 3661 // If there is a negative value, figure out the smallest integer type (of 3662 // int/long/longlong) that fits. 3663 if (NumNegativeBits <= IntWidth && NumPositiveBits < IntWidth) { 3664 BestType = Context.IntTy; 3665 BestWidth = IntWidth; 3666 } else { 3667 BestWidth = Context.Target.getLongWidth(); 3668 3669 if (NumNegativeBits <= BestWidth && NumPositiveBits < BestWidth) 3670 BestType = Context.LongTy; 3671 else { 3672 BestWidth = Context.Target.getLongLongWidth(); 3673 3674 if (NumNegativeBits > BestWidth || NumPositiveBits >= BestWidth) 3675 Diag(Enum->getLocation(), diag::warn_enum_too_large); 3676 BestType = Context.LongLongTy; 3677 } 3678 } 3679 } else { 3680 // If there is no negative value, figure out which of uint, ulong, ulonglong 3681 // fits. 3682 if (NumPositiveBits <= IntWidth) { 3683 BestType = Context.UnsignedIntTy; 3684 BestWidth = IntWidth; 3685 } else if (NumPositiveBits <= 3686 (BestWidth = Context.Target.getLongWidth())) { 3687 BestType = Context.UnsignedLongTy; 3688 } else { 3689 BestWidth = Context.Target.getLongLongWidth(); 3690 assert(NumPositiveBits <= BestWidth && 3691 "How could an initializer get larger than ULL?"); 3692 BestType = Context.UnsignedLongLongTy; 3693 } 3694 } 3695 3696 // Loop over all of the enumerator constants, changing their types to match 3697 // the type of the enum if needed. 3698 for (unsigned i = 0; i != NumElements; ++i) { 3699 EnumConstantDecl *ECD = 3700 cast_or_null<EnumConstantDecl>(static_cast<Decl*>(Elements[i])); 3701 if (!ECD) continue; // Already issued a diagnostic. 3702 3703 // Standard C says the enumerators have int type, but we allow, as an 3704 // extension, the enumerators to be larger than int size. If each 3705 // enumerator value fits in an int, type it as an int, otherwise type it the 3706 // same as the enumerator decl itself. This means that in "enum { X = 1U }" 3707 // that X has type 'int', not 'unsigned'. 3708 if (ECD->getType() == Context.IntTy) { 3709 // Make sure the init value is signed. 3710 llvm::APSInt IV = ECD->getInitVal(); 3711 IV.setIsSigned(true); 3712 ECD->setInitVal(IV); 3713 3714 if (getLangOptions().CPlusPlus) 3715 // C++ [dcl.enum]p4: Following the closing brace of an 3716 // enum-specifier, each enumerator has the type of its 3717 // enumeration. 3718 ECD->setType(EnumType); 3719 continue; // Already int type. 3720 } 3721 3722 // Determine whether the value fits into an int. 3723 llvm::APSInt InitVal = ECD->getInitVal(); 3724 bool FitsInInt; 3725 if (InitVal.isUnsigned() || !InitVal.isNegative()) 3726 FitsInInt = InitVal.getActiveBits() < IntWidth; 3727 else 3728 FitsInInt = InitVal.getMinSignedBits() <= IntWidth; 3729 3730 // If it fits into an integer type, force it. Otherwise force it to match 3731 // the enum decl type. 3732 QualType NewTy; 3733 unsigned NewWidth; 3734 bool NewSign; 3735 if (FitsInInt) { 3736 NewTy = Context.IntTy; 3737 NewWidth = IntWidth; 3738 NewSign = true; 3739 } else if (ECD->getType() == BestType) { 3740 // Already the right type! 3741 if (getLangOptions().CPlusPlus) 3742 // C++ [dcl.enum]p4: Following the closing brace of an 3743 // enum-specifier, each enumerator has the type of its 3744 // enumeration. 3745 ECD->setType(EnumType); 3746 continue; 3747 } else { 3748 NewTy = BestType; 3749 NewWidth = BestWidth; 3750 NewSign = BestType->isSignedIntegerType(); 3751 } 3752 3753 // Adjust the APSInt value. 3754 InitVal.extOrTrunc(NewWidth); 3755 InitVal.setIsSigned(NewSign); 3756 ECD->setInitVal(InitVal); 3757 3758 // Adjust the Expr initializer and type. 3759 if (ECD->getInitExpr()) 3760 ECD->setInitExpr(new ImplicitCastExpr(NewTy, ECD->getInitExpr(), 3761 /*isLvalue=*/false)); 3762 if (getLangOptions().CPlusPlus) 3763 // C++ [dcl.enum]p4: Following the closing brace of an 3764 // enum-specifier, each enumerator has the type of its 3765 // enumeration. 3766 ECD->setType(EnumType); 3767 else 3768 ECD->setType(NewTy); 3769 } 3770 3771 Enum->completeDefinition(Context, BestType); 3772} 3773 3774Sema::DeclTy *Sema::ActOnFileScopeAsmDecl(SourceLocation Loc, 3775 ExprArg expr) { 3776 StringLiteral *AsmString = cast<StringLiteral>((Expr*)expr.release()); 3777 3778 return FileScopeAsmDecl::Create(Context, CurContext, Loc, AsmString); 3779} 3780 3781 3782void Sema::ActOnPragmaPack(PragmaPackKind Kind, IdentifierInfo *Name, 3783 ExprTy *alignment, SourceLocation PragmaLoc, 3784 SourceLocation LParenLoc, SourceLocation RParenLoc) { 3785 Expr *Alignment = static_cast<Expr *>(alignment); 3786 3787 // If specified then alignment must be a "small" power of two. 3788 unsigned AlignmentVal = 0; 3789 if (Alignment) { 3790 llvm::APSInt Val; 3791 if (!Alignment->isIntegerConstantExpr(Val, Context) || 3792 !Val.isPowerOf2() || 3793 Val.getZExtValue() > 16) { 3794 Diag(PragmaLoc, diag::warn_pragma_pack_invalid_alignment); 3795 delete Alignment; 3796 return; // Ignore 3797 } 3798 3799 AlignmentVal = (unsigned) Val.getZExtValue(); 3800 } 3801 3802 switch (Kind) { 3803 case Action::PPK_Default: // pack([n]) 3804 PackContext.setAlignment(AlignmentVal); 3805 break; 3806 3807 case Action::PPK_Show: // pack(show) 3808 // Show the current alignment, making sure to show the right value 3809 // for the default. 3810 AlignmentVal = PackContext.getAlignment(); 3811 // FIXME: This should come from the target. 3812 if (AlignmentVal == 0) 3813 AlignmentVal = 8; 3814 Diag(PragmaLoc, diag::warn_pragma_pack_show) << AlignmentVal; 3815 break; 3816 3817 case Action::PPK_Push: // pack(push [, id] [, [n]) 3818 PackContext.push(Name); 3819 // Set the new alignment if specified. 3820 if (Alignment) 3821 PackContext.setAlignment(AlignmentVal); 3822 break; 3823 3824 case Action::PPK_Pop: // pack(pop [, id] [, n]) 3825 // MSDN, C/C++ Preprocessor Reference > Pragma Directives > pack: 3826 // "#pragma pack(pop, identifier, n) is undefined" 3827 if (Alignment && Name) 3828 Diag(PragmaLoc, diag::warn_pragma_pack_pop_identifer_and_alignment); 3829 3830 // Do the pop. 3831 if (!PackContext.pop(Name)) { 3832 // If a name was specified then failure indicates the name 3833 // wasn't found. Otherwise failure indicates the stack was 3834 // empty. 3835 Diag(PragmaLoc, diag::warn_pragma_pack_pop_failed) 3836 << (Name ? "no record matching name" : "stack empty"); 3837 3838 // FIXME: Warn about popping named records as MSVC does. 3839 } else { 3840 // Pop succeeded, set the new alignment if specified. 3841 if (Alignment) 3842 PackContext.setAlignment(AlignmentVal); 3843 } 3844 break; 3845 3846 default: 3847 assert(0 && "Invalid #pragma pack kind."); 3848 } 3849} 3850 3851bool PragmaPackStack::pop(IdentifierInfo *Name) { 3852 if (Stack.empty()) 3853 return false; 3854 3855 // If name is empty just pop top. 3856 if (!Name) { 3857 Alignment = Stack.back().first; 3858 Stack.pop_back(); 3859 return true; 3860 } 3861 3862 // Otherwise, find the named record. 3863 for (unsigned i = Stack.size(); i != 0; ) { 3864 --i; 3865 if (Stack[i].second == Name) { 3866 // Found it, pop up to and including this record. 3867 Alignment = Stack[i].first; 3868 Stack.erase(Stack.begin() + i, Stack.end()); 3869 return true; 3870 } 3871 } 3872 3873 return false; 3874} 3875