SemaDecl.cpp revision 2b3c3dd9a1ec832b183815ca53737e4c84e02556
1//===--- SemaDecl.cpp - Semantic Analysis for Declarations ----------------===// 2// 3// The LLVM Compiler Infrastructure 4// 5// This file is distributed under the University of Illinois Open Source 6// License. See LICENSE.TXT for details. 7// 8//===----------------------------------------------------------------------===// 9// 10// This file implements semantic analysis for declarations. 11// 12//===----------------------------------------------------------------------===// 13 14#include "Sema.h" 15#include "clang/AST/APValue.h" 16#include "clang/AST/ASTConsumer.h" 17#include "clang/AST/ASTContext.h" 18#include "clang/AST/DeclObjC.h" 19#include "clang/AST/ExprCXX.h" 20#include "clang/Parse/DeclSpec.h" 21#include "clang/Basic/Diagnostic.h" 22#include "clang/Basic/TargetInfo.h" 23#include "clang/Basic/SourceManager.h" 24// FIXME: layering (ideally, Sema shouldn't be dependent on Lex API's) 25#include "clang/Lex/Preprocessor.h" 26#include "clang/Lex/HeaderSearch.h" 27#include "llvm/ADT/SmallSet.h" 28#include "llvm/ADT/STLExtras.h" 29#include <algorithm> 30#include <functional> 31 32using namespace clang; 33 34Sema::TypeTy *Sema::isTypeName(IdentifierInfo &II, Scope *S, 35 const CXXScopeSpec *SS) { 36 DeclContext *DC = 0; 37 if (SS) { 38 if (SS->isInvalid()) 39 return 0; 40 DC = static_cast<DeclContext*>(SS->getScopeRep()); 41 } 42 LookupResult Result = LookupDecl(&II, Decl::IDNS_Ordinary, S, DC, false); 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 (ScopedDecl *SD = dyn_cast<ScopedDecl>(DC)) 92 return SD->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 if (ScopedDecl *SD = dyn_cast<ScopedDecl>(D)) 125 CurContext->addDecl(SD); 126 127 // C++ [basic.scope]p4: 128 // -- exactly one declaration shall declare a class name or 129 // enumeration name that is not a typedef name and the other 130 // declarations shall all refer to the same object or 131 // enumerator, or all refer to functions and function templates; 132 // in this case the class name or enumeration name is hidden. 133 if (TagDecl *TD = dyn_cast<TagDecl>(D)) { 134 // We are pushing the name of a tag (enum or class). 135 if (CurContext->getLookupContext() 136 == TD->getDeclContext()->getLookupContext()) { 137 // We're pushing the tag into the current context, which might 138 // require some reshuffling in the identifier resolver. 139 IdentifierResolver::iterator 140 I = IdResolver.begin(TD->getDeclName(), CurContext, 141 false/*LookInParentCtx*/), 142 IEnd = IdResolver.end(); 143 if (I != IEnd && isDeclInScope(*I, CurContext, S)) { 144 NamedDecl *PrevDecl = *I; 145 for (; I != IEnd && isDeclInScope(*I, CurContext, S); 146 PrevDecl = *I, ++I) { 147 if (TD->declarationReplaces(*I)) { 148 // This is a redeclaration. Remove it from the chain and 149 // break out, so that we'll add in the shadowed 150 // declaration. 151 S->RemoveDecl(*I); 152 if (PrevDecl == *I) { 153 IdResolver.RemoveDecl(*I); 154 IdResolver.AddDecl(TD); 155 return; 156 } else { 157 IdResolver.RemoveDecl(*I); 158 break; 159 } 160 } 161 } 162 163 // There is already a declaration with the same name in the same 164 // scope, which is not a tag declaration. It must be found 165 // before we find the new declaration, so insert the new 166 // declaration at the end of the chain. 167 IdResolver.AddShadowedDecl(TD, PrevDecl); 168 169 return; 170 } 171 } 172 } else if (getLangOptions().CPlusPlus && isa<FunctionDecl>(D)) { 173 // We are pushing the name of a function, which might be an 174 // overloaded name. 175 FunctionDecl *FD = cast<FunctionDecl>(D); 176 DeclContext *DC = FD->getDeclContext()->getLookupContext(); 177 IdentifierResolver::iterator Redecl 178 = std::find_if(IdResolver.begin(FD->getDeclName(), DC, 179 false/*LookInParentCtx*/), 180 IdResolver.end(), 181 std::bind1st(std::mem_fun(&ScopedDecl::declarationReplaces), 182 FD)); 183 if (Redecl != IdResolver.end()) { 184 // There is already a declaration of a function on our 185 // IdResolver chain. Replace it with this declaration. 186 S->RemoveDecl(*Redecl); 187 IdResolver.RemoveDecl(*Redecl); 188 } 189 } 190 191 IdResolver.AddDecl(D); 192} 193 194void Sema::ActOnPopScope(SourceLocation Loc, Scope *S) { 195 if (S->decl_empty()) return; 196 assert((S->getFlags() & (Scope::DeclScope | Scope::TemplateParamScope)) && 197 "Scope shouldn't contain decls!"); 198 199 for (Scope::decl_iterator I = S->decl_begin(), E = S->decl_end(); 200 I != E; ++I) { 201 Decl *TmpD = static_cast<Decl*>(*I); 202 assert(TmpD && "This decl didn't get pushed??"); 203 204 assert(isa<NamedDecl>(TmpD) && "Decl isn't NamedDecl?"); 205 NamedDecl *D = cast<NamedDecl>(TmpD); 206 207 if (!D->getDeclName()) continue; 208 209 // Remove this name from our lexical scope. 210 IdResolver.RemoveDecl(D); 211 } 212} 213 214/// getObjCInterfaceDecl - Look up a for a class declaration in the scope. 215/// return 0 if one not found. 216ObjCInterfaceDecl *Sema::getObjCInterfaceDecl(IdentifierInfo *Id) { 217 // The third "scope" argument is 0 since we aren't enabling lazy built-in 218 // creation from this context. 219 Decl *IDecl = LookupDecl(Id, Decl::IDNS_Ordinary, 0, false); 220 221 return dyn_cast_or_null<ObjCInterfaceDecl>(IDecl); 222} 223 224/// getNonFieldDeclScope - Retrieves the innermost scope, starting 225/// from S, where a non-field would be declared. This routine copes 226/// with the difference between C and C++ scoping rules in structs and 227/// unions. For example, the following code is well-formed in C but 228/// ill-formed in C++: 229/// @code 230/// struct S6 { 231/// enum { BAR } e; 232/// }; 233/// 234/// void test_S6() { 235/// struct S6 a; 236/// a.e = BAR; 237/// } 238/// @endcode 239/// For the declaration of BAR, this routine will return a different 240/// scope. The scope S will be the scope of the unnamed enumeration 241/// within S6. In C++, this routine will return the scope associated 242/// with S6, because the enumeration's scope is a transparent 243/// context but structures can contain non-field names. In C, this 244/// routine will return the translation unit scope, since the 245/// enumeration's scope is a transparent context and structures cannot 246/// contain non-field names. 247Scope *Sema::getNonFieldDeclScope(Scope *S) { 248 while (((S->getFlags() & Scope::DeclScope) == 0) || 249 (S->getEntity() && 250 ((DeclContext *)S->getEntity())->isTransparentContext()) || 251 (S->isClassScope() && !getLangOptions().CPlusPlus)) 252 S = S->getParent(); 253 return S; 254} 255 256/// LookupDecl - Look up the inner-most declaration in the specified 257/// namespace. NamespaceNameOnly - during lookup only namespace names 258/// are considered as required in C++ [basic.lookup.udir] 3.4.6.p1 259/// 'When looking up a namespace-name in a using-directive or 260/// namespace-alias-definition, only namespace names are considered.' 261/// 262/// Note: The use of this routine is deprecated. Please use 263/// LookupName, LookupQualifiedName, or LookupParsedName instead. 264Sema::LookupResult 265Sema::LookupDecl(DeclarationName Name, unsigned NSI, Scope *S, 266 const DeclContext *LookupCtx, 267 bool enableLazyBuiltinCreation, 268 bool LookInParent, 269 bool NamespaceNameOnly) { 270 LookupCriteria::NameKind Kind; 271 if (NSI == Decl::IDNS_Ordinary) { 272 if (NamespaceNameOnly) 273 Kind = LookupCriteria::Namespace; 274 else 275 Kind = LookupCriteria::Ordinary; 276 } else if (NSI == Decl::IDNS_Tag) 277 Kind = LookupCriteria::Tag; 278 else if (NSI == Decl::IDNS_Member) 279 Kind = LookupCriteria::Member; 280 else 281 assert(false && "Unable to grok LookupDecl NSI argument"); 282 283 if (LookupCtx) 284 return LookupQualifiedName(const_cast<DeclContext *>(LookupCtx), Name, 285 LookupCriteria(Kind, !LookInParent, 286 getLangOptions().CPlusPlus)); 287 288 // Unqualified lookup 289 return LookupName(S, Name, 290 LookupCriteria(Kind, !LookInParent, 291 getLangOptions().CPlusPlus)); 292} 293 294void Sema::InitBuiltinVaListType() { 295 if (!Context.getBuiltinVaListType().isNull()) 296 return; 297 298 IdentifierInfo *VaIdent = &Context.Idents.get("__builtin_va_list"); 299 Decl *VaDecl = LookupDecl(VaIdent, Decl::IDNS_Ordinary, TUScope); 300 TypedefDecl *VaTypedef = cast<TypedefDecl>(VaDecl); 301 Context.setBuiltinVaListType(Context.getTypedefType(VaTypedef)); 302} 303 304/// LazilyCreateBuiltin - The specified Builtin-ID was first used at file scope. 305/// lazily create a decl for it. 306ScopedDecl *Sema::LazilyCreateBuiltin(IdentifierInfo *II, unsigned bid, 307 Scope *S) { 308 Builtin::ID BID = (Builtin::ID)bid; 309 310 if (Context.BuiltinInfo.hasVAListUse(BID)) 311 InitBuiltinVaListType(); 312 313 QualType R = Context.BuiltinInfo.GetBuiltinType(BID, Context); 314 FunctionDecl *New = FunctionDecl::Create(Context, 315 Context.getTranslationUnitDecl(), 316 SourceLocation(), II, R, 317 FunctionDecl::Extern, false, 0); 318 319 // Create Decl objects for each parameter, adding them to the 320 // FunctionDecl. 321 if (FunctionTypeProto *FT = dyn_cast<FunctionTypeProto>(R)) { 322 llvm::SmallVector<ParmVarDecl*, 16> Params; 323 for (unsigned i = 0, e = FT->getNumArgs(); i != e; ++i) 324 Params.push_back(ParmVarDecl::Create(Context, New, SourceLocation(), 0, 325 FT->getArgType(i), VarDecl::None, 0, 326 0)); 327 New->setParams(Context, &Params[0], Params.size()); 328 } 329 330 331 332 // TUScope is the translation-unit scope to insert this function into. 333 // FIXME: This is hideous. We need to teach PushOnScopeChains to 334 // relate Scopes to DeclContexts, and probably eliminate CurContext 335 // entirely, but we're not there yet. 336 DeclContext *SavedContext = CurContext; 337 CurContext = Context.getTranslationUnitDecl(); 338 PushOnScopeChains(New, TUScope); 339 CurContext = SavedContext; 340 return New; 341} 342 343/// GetStdNamespace - This method gets the C++ "std" namespace. This is where 344/// everything from the standard library is defined. 345NamespaceDecl *Sema::GetStdNamespace() { 346 if (!StdNamespace) { 347 IdentifierInfo *StdIdent = &PP.getIdentifierTable().get("std"); 348 DeclContext *Global = Context.getTranslationUnitDecl(); 349 Decl *Std = LookupDecl(StdIdent, Decl::IDNS_Ordinary, 350 0, Global, /*enableLazyBuiltinCreation=*/false); 351 StdNamespace = dyn_cast_or_null<NamespaceDecl>(Std); 352 } 353 return StdNamespace; 354} 355 356/// MergeTypeDefDecl - We just parsed a typedef 'New' which has the same name 357/// and scope as a previous declaration 'Old'. Figure out how to resolve this 358/// situation, merging decls or emitting diagnostics as appropriate. 359/// 360TypedefDecl *Sema::MergeTypeDefDecl(TypedefDecl *New, Decl *OldD) { 361 // Allow multiple definitions for ObjC built-in typedefs. 362 // FIXME: Verify the underlying types are equivalent! 363 if (getLangOptions().ObjC1) { 364 const IdentifierInfo *TypeID = New->getIdentifier(); 365 switch (TypeID->getLength()) { 366 default: break; 367 case 2: 368 if (!TypeID->isStr("id")) 369 break; 370 Context.setObjCIdType(New); 371 return New; 372 case 5: 373 if (!TypeID->isStr("Class")) 374 break; 375 Context.setObjCClassType(New); 376 return New; 377 case 3: 378 if (!TypeID->isStr("SEL")) 379 break; 380 Context.setObjCSelType(New); 381 return New; 382 case 8: 383 if (!TypeID->isStr("Protocol")) 384 break; 385 Context.setObjCProtoType(New->getUnderlyingType()); 386 return New; 387 } 388 // Fall through - the typedef name was not a builtin type. 389 } 390 // Verify the old decl was also a typedef. 391 TypedefDecl *Old = dyn_cast<TypedefDecl>(OldD); 392 if (!Old) { 393 Diag(New->getLocation(), diag::err_redefinition_different_kind) 394 << New->getDeclName(); 395 Diag(OldD->getLocation(), diag::note_previous_definition); 396 return New; 397 } 398 399 // If the typedef types are not identical, reject them in all languages and 400 // with any extensions enabled. 401 if (Old->getUnderlyingType() != New->getUnderlyingType() && 402 Context.getCanonicalType(Old->getUnderlyingType()) != 403 Context.getCanonicalType(New->getUnderlyingType())) { 404 Diag(New->getLocation(), diag::err_redefinition_different_typedef) 405 << New->getUnderlyingType() << Old->getUnderlyingType(); 406 Diag(Old->getLocation(), diag::note_previous_definition); 407 return New; 408 } 409 410 if (getLangOptions().Microsoft) return New; 411 412 // C++ [dcl.typedef]p2: 413 // In a given non-class scope, a typedef specifier can be used to 414 // redefine the name of any type declared in that scope to refer 415 // to the type to which it already refers. 416 if (getLangOptions().CPlusPlus && !isa<CXXRecordDecl>(CurContext)) 417 return New; 418 419 // In C, redeclaration of a type is a constraint violation (6.7.2.3p1). 420 // Apparently GCC, Intel, and Sun all silently ignore the redeclaration if 421 // *either* declaration is in a system header. The code below implements 422 // this adhoc compatibility rule. FIXME: The following code will not 423 // work properly when compiling ".i" files (containing preprocessed output). 424 if (PP.getDiagnostics().getSuppressSystemWarnings()) { 425 SourceManager &SrcMgr = Context.getSourceManager(); 426 if (SrcMgr.isInSystemHeader(Old->getLocation())) 427 return New; 428 if (SrcMgr.isInSystemHeader(New->getLocation())) 429 return New; 430 } 431 432 Diag(New->getLocation(), diag::err_redefinition) << New->getDeclName(); 433 Diag(Old->getLocation(), diag::note_previous_definition); 434 return New; 435} 436 437/// DeclhasAttr - returns true if decl Declaration already has the target 438/// attribute. 439static bool DeclHasAttr(const Decl *decl, const Attr *target) { 440 for (const Attr *attr = decl->getAttrs(); attr; attr = attr->getNext()) 441 if (attr->getKind() == target->getKind()) 442 return true; 443 444 return false; 445} 446 447/// MergeAttributes - append attributes from the Old decl to the New one. 448static void MergeAttributes(Decl *New, Decl *Old) { 449 Attr *attr = const_cast<Attr*>(Old->getAttrs()), *tmp; 450 451 while (attr) { 452 tmp = attr; 453 attr = attr->getNext(); 454 455 if (!DeclHasAttr(New, tmp)) { 456 tmp->setInherited(true); 457 New->addAttr(tmp); 458 } else { 459 tmp->setNext(0); 460 delete(tmp); 461 } 462 } 463 464 Old->invalidateAttrs(); 465} 466 467/// MergeFunctionDecl - We just parsed a function 'New' from 468/// declarator D which has the same name and scope as a previous 469/// declaration 'Old'. Figure out how to resolve this situation, 470/// merging decls or emitting diagnostics as appropriate. 471/// Redeclaration will be set true if this New is a redeclaration OldD. 472/// 473/// In C++, New and Old must be declarations that are not 474/// overloaded. Use IsOverload to determine whether New and Old are 475/// overloaded, and to select the Old declaration that New should be 476/// merged with. 477FunctionDecl * 478Sema::MergeFunctionDecl(FunctionDecl *New, Decl *OldD, bool &Redeclaration) { 479 assert(!isa<OverloadedFunctionDecl>(OldD) && 480 "Cannot merge with an overloaded function declaration"); 481 482 Redeclaration = false; 483 // Verify the old decl was also a function. 484 FunctionDecl *Old = dyn_cast<FunctionDecl>(OldD); 485 if (!Old) { 486 Diag(New->getLocation(), diag::err_redefinition_different_kind) 487 << New->getDeclName(); 488 Diag(OldD->getLocation(), diag::note_previous_definition); 489 return New; 490 } 491 492 // Determine whether the previous declaration was a definition, 493 // implicit declaration, or a declaration. 494 diag::kind PrevDiag; 495 if (Old->isThisDeclarationADefinition()) 496 PrevDiag = diag::note_previous_definition; 497 else if (Old->isImplicit()) 498 PrevDiag = diag::note_previous_implicit_declaration; 499 else 500 PrevDiag = diag::note_previous_declaration; 501 502 QualType OldQType = Context.getCanonicalType(Old->getType()); 503 QualType NewQType = Context.getCanonicalType(New->getType()); 504 505 if (getLangOptions().CPlusPlus) { 506 // (C++98 13.1p2): 507 // Certain function declarations cannot be overloaded: 508 // -- Function declarations that differ only in the return type 509 // cannot be overloaded. 510 QualType OldReturnType 511 = cast<FunctionType>(OldQType.getTypePtr())->getResultType(); 512 QualType NewReturnType 513 = cast<FunctionType>(NewQType.getTypePtr())->getResultType(); 514 if (OldReturnType != NewReturnType) { 515 Diag(New->getLocation(), diag::err_ovl_diff_return_type); 516 Diag(Old->getLocation(), PrevDiag); 517 Redeclaration = true; 518 return New; 519 } 520 521 const CXXMethodDecl* OldMethod = dyn_cast<CXXMethodDecl>(Old); 522 const CXXMethodDecl* NewMethod = dyn_cast<CXXMethodDecl>(New); 523 if (OldMethod && NewMethod) { 524 // -- Member function declarations with the same name and the 525 // same parameter types cannot be overloaded if any of them 526 // is a static member function declaration. 527 if (OldMethod->isStatic() || NewMethod->isStatic()) { 528 Diag(New->getLocation(), diag::err_ovl_static_nonstatic_member); 529 Diag(Old->getLocation(), PrevDiag); 530 return New; 531 } 532 533 // C++ [class.mem]p1: 534 // [...] A member shall not be declared twice in the 535 // member-specification, except that a nested class or member 536 // class template can be declared and then later defined. 537 if (OldMethod->getLexicalDeclContext() == 538 NewMethod->getLexicalDeclContext()) { 539 unsigned NewDiag; 540 if (isa<CXXConstructorDecl>(OldMethod)) 541 NewDiag = diag::err_constructor_redeclared; 542 else if (isa<CXXDestructorDecl>(NewMethod)) 543 NewDiag = diag::err_destructor_redeclared; 544 else if (isa<CXXConversionDecl>(NewMethod)) 545 NewDiag = diag::err_conv_function_redeclared; 546 else 547 NewDiag = diag::err_member_redeclared; 548 549 Diag(New->getLocation(), NewDiag); 550 Diag(Old->getLocation(), PrevDiag); 551 } 552 } 553 554 // (C++98 8.3.5p3): 555 // All declarations for a function shall agree exactly in both the 556 // return type and the parameter-type-list. 557 if (OldQType == NewQType) { 558 // We have a redeclaration. 559 MergeAttributes(New, Old); 560 Redeclaration = true; 561 return MergeCXXFunctionDecl(New, Old); 562 } 563 564 // Fall through for conflicting redeclarations and redefinitions. 565 } 566 567 // C: Function types need to be compatible, not identical. This handles 568 // duplicate function decls like "void f(int); void f(enum X);" properly. 569 if (!getLangOptions().CPlusPlus && 570 Context.typesAreCompatible(OldQType, NewQType)) { 571 MergeAttributes(New, Old); 572 Redeclaration = true; 573 return New; 574 } 575 576 // A function that has already been declared has been redeclared or defined 577 // with a different type- show appropriate diagnostic 578 579 // TODO: CHECK FOR CONFLICTS, multiple decls with same name in one scope. 580 // TODO: This is totally simplistic. It should handle merging functions 581 // together etc, merging extern int X; int X; ... 582 Diag(New->getLocation(), diag::err_conflicting_types) << New->getDeclName(); 583 Diag(Old->getLocation(), PrevDiag); 584 return New; 585} 586 587/// Predicate for C "tentative" external object definitions (C99 6.9.2). 588static bool isTentativeDefinition(VarDecl *VD) { 589 if (VD->isFileVarDecl()) 590 return (!VD->getInit() && 591 (VD->getStorageClass() == VarDecl::None || 592 VD->getStorageClass() == VarDecl::Static)); 593 return false; 594} 595 596/// CheckForFileScopedRedefinitions - Make sure we forgo redefinition errors 597/// when dealing with C "tentative" external object definitions (C99 6.9.2). 598void Sema::CheckForFileScopedRedefinitions(Scope *S, VarDecl *VD) { 599 bool VDIsTentative = isTentativeDefinition(VD); 600 bool VDIsIncompleteArray = VD->getType()->isIncompleteArrayType(); 601 602 // FIXME: I don't think this will actually see all of the 603 // redefinitions. Can't we check this property on-the-fly? 604 for (IdentifierResolver::iterator 605 I = IdResolver.begin(VD->getIdentifier(), 606 VD->getDeclContext(), false/*LookInParentCtx*/), 607 E = IdResolver.end(); I != E; ++I) { 608 if (*I != VD && isDeclInScope(*I, VD->getDeclContext(), S)) { 609 VarDecl *OldDecl = dyn_cast<VarDecl>(*I); 610 611 // Handle the following case: 612 // int a[10]; 613 // int a[]; - the code below makes sure we set the correct type. 614 // int a[11]; - this is an error, size isn't 10. 615 if (OldDecl && VDIsTentative && VDIsIncompleteArray && 616 OldDecl->getType()->isConstantArrayType()) 617 VD->setType(OldDecl->getType()); 618 619 // Check for "tentative" definitions. We can't accomplish this in 620 // MergeVarDecl since the initializer hasn't been attached. 621 if (!OldDecl || isTentativeDefinition(OldDecl) || VDIsTentative) 622 continue; 623 624 // Handle __private_extern__ just like extern. 625 if (OldDecl->getStorageClass() != VarDecl::Extern && 626 OldDecl->getStorageClass() != VarDecl::PrivateExtern && 627 VD->getStorageClass() != VarDecl::Extern && 628 VD->getStorageClass() != VarDecl::PrivateExtern) { 629 Diag(VD->getLocation(), diag::err_redefinition) << VD->getDeclName(); 630 Diag(OldDecl->getLocation(), diag::note_previous_definition); 631 } 632 } 633 } 634} 635 636/// MergeVarDecl - We just parsed a variable 'New' which has the same name 637/// and scope as a previous declaration 'Old'. Figure out how to resolve this 638/// situation, merging decls or emitting diagnostics as appropriate. 639/// 640/// Tentative definition rules (C99 6.9.2p2) are checked by 641/// FinalizeDeclaratorGroup. Unfortunately, we can't analyze tentative 642/// definitions here, since the initializer hasn't been attached. 643/// 644VarDecl *Sema::MergeVarDecl(VarDecl *New, Decl *OldD) { 645 // Verify the old decl was also a variable. 646 VarDecl *Old = dyn_cast<VarDecl>(OldD); 647 if (!Old) { 648 Diag(New->getLocation(), diag::err_redefinition_different_kind) 649 << New->getDeclName(); 650 Diag(OldD->getLocation(), diag::note_previous_definition); 651 return New; 652 } 653 654 MergeAttributes(New, Old); 655 656 // Verify the types match. 657 QualType OldCType = Context.getCanonicalType(Old->getType()); 658 QualType NewCType = Context.getCanonicalType(New->getType()); 659 if (OldCType != NewCType && !Context.typesAreCompatible(OldCType, NewCType)) { 660 Diag(New->getLocation(), diag::err_redefinition_different_type) 661 << New->getDeclName(); 662 Diag(Old->getLocation(), diag::note_previous_definition); 663 return New; 664 } 665 // C99 6.2.2p4: Check if we have a static decl followed by a non-static. 666 if (New->getStorageClass() == VarDecl::Static && 667 (Old->getStorageClass() == VarDecl::None || 668 Old->getStorageClass() == VarDecl::Extern)) { 669 Diag(New->getLocation(), diag::err_static_non_static) << New->getDeclName(); 670 Diag(Old->getLocation(), diag::note_previous_definition); 671 return New; 672 } 673 // C99 6.2.2p4: Check if we have a non-static decl followed by a static. 674 if (New->getStorageClass() != VarDecl::Static && 675 Old->getStorageClass() == VarDecl::Static) { 676 Diag(New->getLocation(), diag::err_non_static_static) << New->getDeclName(); 677 Diag(Old->getLocation(), diag::note_previous_definition); 678 return New; 679 } 680 // Variables with external linkage are analyzed in FinalizeDeclaratorGroup. 681 if (New->getStorageClass() != VarDecl::Extern && !New->isFileVarDecl()) { 682 Diag(New->getLocation(), diag::err_redefinition) << New->getDeclName(); 683 Diag(Old->getLocation(), diag::note_previous_definition); 684 } 685 return New; 686} 687 688/// CheckParmsForFunctionDef - Check that the parameters of the given 689/// function are appropriate for the definition of a function. This 690/// takes care of any checks that cannot be performed on the 691/// declaration itself, e.g., that the types of each of the function 692/// parameters are complete. 693bool Sema::CheckParmsForFunctionDef(FunctionDecl *FD) { 694 bool HasInvalidParm = false; 695 for (unsigned p = 0, NumParams = FD->getNumParams(); p < NumParams; ++p) { 696 ParmVarDecl *Param = FD->getParamDecl(p); 697 698 // C99 6.7.5.3p4: the parameters in a parameter type list in a 699 // function declarator that is part of a function definition of 700 // that function shall not have incomplete type. 701 if (Param->getType()->isIncompleteType() && 702 !Param->isInvalidDecl()) { 703 Diag(Param->getLocation(), diag::err_typecheck_decl_incomplete_type) 704 << Param->getType(); 705 Param->setInvalidDecl(); 706 HasInvalidParm = true; 707 } 708 709 // C99 6.9.1p5: If the declarator includes a parameter type list, the 710 // declaration of each parameter shall include an identifier. 711 if (Param->getIdentifier() == 0 && !getLangOptions().CPlusPlus) 712 Diag(Param->getLocation(), diag::err_parameter_name_omitted); 713 } 714 715 return HasInvalidParm; 716} 717 718/// ParsedFreeStandingDeclSpec - This method is invoked when a declspec with 719/// no declarator (e.g. "struct foo;") is parsed. 720Sema::DeclTy *Sema::ParsedFreeStandingDeclSpec(Scope *S, DeclSpec &DS) { 721 TagDecl *Tag 722 = dyn_cast_or_null<TagDecl>(static_cast<Decl *>(DS.getTypeRep())); 723 if (RecordDecl *Record = dyn_cast_or_null<RecordDecl>(Tag)) { 724 if (!Record->getDeclName() && Record->isDefinition() && 725 DS.getStorageClassSpec() != DeclSpec::SCS_typedef) 726 return BuildAnonymousStructOrUnion(S, DS, Record); 727 728 // Microsoft allows unnamed struct/union fields. Don't complain 729 // about them. 730 // FIXME: Should we support Microsoft's extensions in this area? 731 if (Record->getDeclName() && getLangOptions().Microsoft) 732 return Tag; 733 } 734 735 // Permit typedefs without declarators as a Microsoft extension. 736 if (!DS.isMissingDeclaratorOk()) { 737 if (getLangOptions().Microsoft && 738 DS.getStorageClassSpec() == DeclSpec::SCS_typedef) { 739 Diag(DS.getSourceRange().getBegin(), diag::ext_no_declarators) 740 << DS.getSourceRange(); 741 return Tag; 742 } 743 744 // FIXME: This diagnostic is emitted even when various previous 745 // errors occurred (see e.g. test/Sema/decl-invalid.c). However, 746 // DeclSpec has no means of communicating this information, and the 747 // responsible parser functions are quite far apart. 748 Diag(DS.getSourceRange().getBegin(), diag::err_no_declarators) 749 << DS.getSourceRange(); 750 return 0; 751 } 752 753 return Tag; 754} 755 756/// InjectAnonymousStructOrUnionMembers - Inject the members of the 757/// anonymous struct or union AnonRecord into the owning context Owner 758/// and scope S. This routine will be invoked just after we realize 759/// that an unnamed union or struct is actually an anonymous union or 760/// struct, e.g., 761/// 762/// @code 763/// union { 764/// int i; 765/// float f; 766/// }; // InjectAnonymousStructOrUnionMembers called here to inject i and 767/// // f into the surrounding scope.x 768/// @endcode 769/// 770/// This routine is recursive, injecting the names of nested anonymous 771/// structs/unions into the owning context and scope as well. 772bool Sema::InjectAnonymousStructOrUnionMembers(Scope *S, DeclContext *Owner, 773 RecordDecl *AnonRecord) { 774 bool Invalid = false; 775 for (RecordDecl::field_iterator F = AnonRecord->field_begin(), 776 FEnd = AnonRecord->field_end(); 777 F != FEnd; ++F) { 778 if ((*F)->getDeclName()) { 779 Decl *PrevDecl = LookupDecl((*F)->getDeclName(), Decl::IDNS_Ordinary, 780 S, Owner, false, false, false); 781 if (PrevDecl && !isa<TagDecl>(PrevDecl)) { 782 // C++ [class.union]p2: 783 // The names of the members of an anonymous union shall be 784 // distinct from the names of any other entity in the 785 // scope in which the anonymous union is declared. 786 unsigned diagKind 787 = AnonRecord->isUnion()? diag::err_anonymous_union_member_redecl 788 : diag::err_anonymous_struct_member_redecl; 789 Diag((*F)->getLocation(), diagKind) 790 << (*F)->getDeclName(); 791 Diag(PrevDecl->getLocation(), diag::note_previous_declaration); 792 Invalid = true; 793 } else { 794 // C++ [class.union]p2: 795 // For the purpose of name lookup, after the anonymous union 796 // definition, the members of the anonymous union are 797 // considered to have been defined in the scope in which the 798 // anonymous union is declared. 799 Owner->insert(*F); 800 S->AddDecl(*F); 801 IdResolver.AddDecl(*F); 802 } 803 } else if (const RecordType *InnerRecordType 804 = (*F)->getType()->getAsRecordType()) { 805 RecordDecl *InnerRecord = InnerRecordType->getDecl(); 806 if (InnerRecord->isAnonymousStructOrUnion()) 807 Invalid = Invalid || 808 InjectAnonymousStructOrUnionMembers(S, Owner, InnerRecord); 809 } 810 } 811 812 return Invalid; 813} 814 815/// ActOnAnonymousStructOrUnion - Handle the declaration of an 816/// anonymous structure or union. Anonymous unions are a C++ feature 817/// (C++ [class.union]) and a GNU C extension; anonymous structures 818/// are a GNU C and GNU C++ extension. 819Sema::DeclTy *Sema::BuildAnonymousStructOrUnion(Scope *S, DeclSpec &DS, 820 RecordDecl *Record) { 821 DeclContext *Owner = Record->getDeclContext(); 822 823 // Diagnose whether this anonymous struct/union is an extension. 824 if (Record->isUnion() && !getLangOptions().CPlusPlus) 825 Diag(Record->getLocation(), diag::ext_anonymous_union); 826 else if (!Record->isUnion()) 827 Diag(Record->getLocation(), diag::ext_anonymous_struct); 828 829 // C and C++ require different kinds of checks for anonymous 830 // structs/unions. 831 bool Invalid = false; 832 if (getLangOptions().CPlusPlus) { 833 const char* PrevSpec = 0; 834 // C++ [class.union]p3: 835 // Anonymous unions declared in a named namespace or in the 836 // global namespace shall be declared static. 837 if (DS.getStorageClassSpec() != DeclSpec::SCS_static && 838 (isa<TranslationUnitDecl>(Owner) || 839 (isa<NamespaceDecl>(Owner) && 840 cast<NamespaceDecl>(Owner)->getDeclName()))) { 841 Diag(Record->getLocation(), diag::err_anonymous_union_not_static); 842 Invalid = true; 843 844 // Recover by adding 'static'. 845 DS.SetStorageClassSpec(DeclSpec::SCS_static, SourceLocation(), PrevSpec); 846 } 847 // C++ [class.union]p3: 848 // A storage class is not allowed in a declaration of an 849 // anonymous union in a class scope. 850 else if (DS.getStorageClassSpec() != DeclSpec::SCS_unspecified && 851 isa<RecordDecl>(Owner)) { 852 Diag(DS.getStorageClassSpecLoc(), 853 diag::err_anonymous_union_with_storage_spec); 854 Invalid = true; 855 856 // Recover by removing the storage specifier. 857 DS.SetStorageClassSpec(DeclSpec::SCS_unspecified, SourceLocation(), 858 PrevSpec); 859 } 860 861 // C++ [class.union]p2: 862 // The member-specification of an anonymous union shall only 863 // define non-static data members. [Note: nested types and 864 // functions cannot be declared within an anonymous union. ] 865 for (DeclContext::decl_iterator Mem = Record->decls_begin(), 866 MemEnd = Record->decls_end(); 867 Mem != MemEnd; ++Mem) { 868 if (FieldDecl *FD = dyn_cast<FieldDecl>(*Mem)) { 869 // C++ [class.union]p3: 870 // An anonymous union shall not have private or protected 871 // members (clause 11). 872 if (FD->getAccess() == AS_protected || FD->getAccess() == AS_private) { 873 Diag(FD->getLocation(), diag::err_anonymous_record_nonpublic_member) 874 << (int)Record->isUnion() << (int)(FD->getAccess() == AS_protected); 875 Invalid = true; 876 } 877 } else if ((*Mem)->isImplicit()) { 878 // Any implicit members are fine. 879 } else if (RecordDecl *MemRecord = dyn_cast<RecordDecl>(*Mem)) { 880 if (!MemRecord->isAnonymousStructOrUnion() && 881 MemRecord->getDeclName()) { 882 // This is a nested type declaration. 883 Diag(MemRecord->getLocation(), diag::err_anonymous_record_with_type) 884 << (int)Record->isUnion(); 885 Invalid = true; 886 } 887 } else { 888 // We have something that isn't a non-static data 889 // member. Complain about it. 890 unsigned DK = diag::err_anonymous_record_bad_member; 891 if (isa<TypeDecl>(*Mem)) 892 DK = diag::err_anonymous_record_with_type; 893 else if (isa<FunctionDecl>(*Mem)) 894 DK = diag::err_anonymous_record_with_function; 895 else if (isa<VarDecl>(*Mem)) 896 DK = diag::err_anonymous_record_with_static; 897 Diag((*Mem)->getLocation(), DK) 898 << (int)Record->isUnion(); 899 Invalid = true; 900 } 901 } 902 } else { 903 // FIXME: Check GNU C semantics 904 if (Record->isUnion() && !Owner->isRecord()) { 905 Diag(Record->getLocation(), diag::err_anonymous_union_not_member) 906 << (int)getLangOptions().CPlusPlus; 907 Invalid = true; 908 } 909 } 910 911 if (!Record->isUnion() && !Owner->isRecord()) { 912 Diag(Record->getLocation(), diag::err_anonymous_struct_not_member) 913 << (int)getLangOptions().CPlusPlus; 914 Invalid = true; 915 } 916 917 // Create a declaration for this anonymous struct/union. 918 ScopedDecl *Anon = 0; 919 if (RecordDecl *OwningClass = dyn_cast<RecordDecl>(Owner)) { 920 Anon = FieldDecl::Create(Context, OwningClass, Record->getLocation(), 921 /*IdentifierInfo=*/0, 922 Context.getTypeDeclType(Record), 923 /*BitWidth=*/0, /*Mutable=*/false, 924 /*PrevDecl=*/0); 925 Anon->setAccess(AS_public); 926 if (getLangOptions().CPlusPlus) 927 FieldCollector->Add(cast<FieldDecl>(Anon)); 928 } else { 929 VarDecl::StorageClass SC; 930 switch (DS.getStorageClassSpec()) { 931 default: assert(0 && "Unknown storage class!"); 932 case DeclSpec::SCS_unspecified: SC = VarDecl::None; break; 933 case DeclSpec::SCS_extern: SC = VarDecl::Extern; break; 934 case DeclSpec::SCS_static: SC = VarDecl::Static; break; 935 case DeclSpec::SCS_auto: SC = VarDecl::Auto; break; 936 case DeclSpec::SCS_register: SC = VarDecl::Register; break; 937 case DeclSpec::SCS_private_extern: SC = VarDecl::PrivateExtern; break; 938 case DeclSpec::SCS_mutable: 939 // mutable can only appear on non-static class members, so it's always 940 // an error here 941 Diag(Record->getLocation(), diag::err_mutable_nonmember); 942 Invalid = true; 943 SC = VarDecl::None; 944 break; 945 } 946 947 Anon = VarDecl::Create(Context, Owner, Record->getLocation(), 948 /*IdentifierInfo=*/0, 949 Context.getTypeDeclType(Record), 950 SC, /*FIXME:LastDeclarator=*/0, 951 DS.getSourceRange().getBegin()); 952 } 953 Anon->setImplicit(); 954 955 // Add the anonymous struct/union object to the current 956 // context. We'll be referencing this object when we refer to one of 957 // its members. 958 Owner->addDecl(Anon); 959 960 // Inject the members of the anonymous struct/union into the owning 961 // context and into the identifier resolver chain for name lookup 962 // purposes. 963 if (InjectAnonymousStructOrUnionMembers(S, Owner, Record)) 964 Invalid = true; 965 966 // Mark this as an anonymous struct/union type. Note that we do not 967 // do this until after we have already checked and injected the 968 // members of this anonymous struct/union type, because otherwise 969 // the members could be injected twice: once by DeclContext when it 970 // builds its lookup table, and once by 971 // InjectAnonymousStructOrUnionMembers. 972 Record->setAnonymousStructOrUnion(true); 973 974 if (Invalid) 975 Anon->setInvalidDecl(); 976 977 return Anon; 978} 979 980bool Sema::CheckSingleInitializer(Expr *&Init, QualType DeclType, 981 bool DirectInit) { 982 // Get the type before calling CheckSingleAssignmentConstraints(), since 983 // it can promote the expression. 984 QualType InitType = Init->getType(); 985 986 if (getLangOptions().CPlusPlus) { 987 // FIXME: I dislike this error message. A lot. 988 if (PerformImplicitConversion(Init, DeclType, "initializing", DirectInit)) 989 return Diag(Init->getSourceRange().getBegin(), 990 diag::err_typecheck_convert_incompatible) 991 << DeclType << Init->getType() << "initializing" 992 << Init->getSourceRange(); 993 994 return false; 995 } 996 997 AssignConvertType ConvTy = CheckSingleAssignmentConstraints(DeclType, Init); 998 return DiagnoseAssignmentResult(ConvTy, Init->getLocStart(), DeclType, 999 InitType, Init, "initializing"); 1000} 1001 1002bool Sema::CheckStringLiteralInit(StringLiteral *strLiteral, QualType &DeclT) { 1003 const ArrayType *AT = Context.getAsArrayType(DeclT); 1004 1005 if (const IncompleteArrayType *IAT = dyn_cast<IncompleteArrayType>(AT)) { 1006 // C99 6.7.8p14. We have an array of character type with unknown size 1007 // being initialized to a string literal. 1008 llvm::APSInt ConstVal(32); 1009 ConstVal = strLiteral->getByteLength() + 1; 1010 // Return a new array type (C99 6.7.8p22). 1011 DeclT = Context.getConstantArrayType(IAT->getElementType(), ConstVal, 1012 ArrayType::Normal, 0); 1013 } else { 1014 const ConstantArrayType *CAT = cast<ConstantArrayType>(AT); 1015 // C99 6.7.8p14. We have an array of character type with known size. 1016 // FIXME: Avoid truncation for 64-bit length strings. 1017 if (strLiteral->getByteLength() > (unsigned)CAT->getSize().getZExtValue()) 1018 Diag(strLiteral->getSourceRange().getBegin(), 1019 diag::warn_initializer_string_for_char_array_too_long) 1020 << strLiteral->getSourceRange(); 1021 } 1022 // Set type from "char *" to "constant array of char". 1023 strLiteral->setType(DeclT); 1024 // For now, we always return false (meaning success). 1025 return false; 1026} 1027 1028StringLiteral *Sema::IsStringLiteralInit(Expr *Init, QualType DeclType) { 1029 const ArrayType *AT = Context.getAsArrayType(DeclType); 1030 if (AT && AT->getElementType()->isCharType()) { 1031 return dyn_cast<StringLiteral>(Init); 1032 } 1033 return 0; 1034} 1035 1036bool Sema::CheckInitializerTypes(Expr *&Init, QualType &DeclType, 1037 SourceLocation InitLoc, 1038 DeclarationName InitEntity, 1039 bool DirectInit) { 1040 if (DeclType->isDependentType() || Init->isTypeDependent()) 1041 return false; 1042 1043 // C++ [dcl.init.ref]p1: 1044 // A variable declared to be a T&, that is "reference to type T" 1045 // (8.3.2), shall be initialized by an object, or function, of 1046 // type T or by an object that can be converted into a T. 1047 if (DeclType->isReferenceType()) 1048 return CheckReferenceInit(Init, DeclType, 0, false, DirectInit); 1049 1050 // C99 6.7.8p3: The type of the entity to be initialized shall be an array 1051 // of unknown size ("[]") or an object type that is not a variable array type. 1052 if (const VariableArrayType *VAT = Context.getAsVariableArrayType(DeclType)) 1053 return Diag(InitLoc, diag::err_variable_object_no_init) 1054 << VAT->getSizeExpr()->getSourceRange(); 1055 1056 InitListExpr *InitList = dyn_cast<InitListExpr>(Init); 1057 if (!InitList) { 1058 // FIXME: Handle wide strings 1059 if (StringLiteral *strLiteral = IsStringLiteralInit(Init, DeclType)) 1060 return CheckStringLiteralInit(strLiteral, DeclType); 1061 1062 // C++ [dcl.init]p14: 1063 // -- If the destination type is a (possibly cv-qualified) class 1064 // type: 1065 if (getLangOptions().CPlusPlus && DeclType->isRecordType()) { 1066 QualType DeclTypeC = Context.getCanonicalType(DeclType); 1067 QualType InitTypeC = Context.getCanonicalType(Init->getType()); 1068 1069 // -- If the initialization is direct-initialization, or if it is 1070 // copy-initialization where the cv-unqualified version of the 1071 // source type is the same class as, or a derived class of, the 1072 // class of the destination, constructors are considered. 1073 if ((DeclTypeC.getUnqualifiedType() == InitTypeC.getUnqualifiedType()) || 1074 IsDerivedFrom(InitTypeC, DeclTypeC)) { 1075 CXXConstructorDecl *Constructor 1076 = PerformInitializationByConstructor(DeclType, &Init, 1, 1077 InitLoc, Init->getSourceRange(), 1078 InitEntity, 1079 DirectInit? IK_Direct : IK_Copy); 1080 return Constructor == 0; 1081 } 1082 1083 // -- Otherwise (i.e., for the remaining copy-initialization 1084 // cases), user-defined conversion sequences that can 1085 // convert from the source type to the destination type or 1086 // (when a conversion function is used) to a derived class 1087 // thereof are enumerated as described in 13.3.1.4, and the 1088 // best one is chosen through overload resolution 1089 // (13.3). If the conversion cannot be done or is 1090 // ambiguous, the initialization is ill-formed. The 1091 // function selected is called with the initializer 1092 // expression as its argument; if the function is a 1093 // constructor, the call initializes a temporary of the 1094 // destination type. 1095 // FIXME: We're pretending to do copy elision here; return to 1096 // this when we have ASTs for such things. 1097 if (!PerformImplicitConversion(Init, DeclType, "initializing")) 1098 return false; 1099 1100 if (InitEntity) 1101 return Diag(InitLoc, diag::err_cannot_initialize_decl) 1102 << InitEntity << (int)(Init->isLvalue(Context) == Expr::LV_Valid) 1103 << Init->getType() << Init->getSourceRange(); 1104 else 1105 return Diag(InitLoc, diag::err_cannot_initialize_decl_noname) 1106 << DeclType << (int)(Init->isLvalue(Context) == Expr::LV_Valid) 1107 << Init->getType() << Init->getSourceRange(); 1108 } 1109 1110 // C99 6.7.8p16. 1111 if (DeclType->isArrayType()) 1112 return Diag(Init->getLocStart(), diag::err_array_init_list_required) 1113 << Init->getSourceRange(); 1114 1115 return CheckSingleInitializer(Init, DeclType, DirectInit); 1116 } else if (getLangOptions().CPlusPlus) { 1117 // C++ [dcl.init]p14: 1118 // [...] If the class is an aggregate (8.5.1), and the initializer 1119 // is a brace-enclosed list, see 8.5.1. 1120 // 1121 // Note: 8.5.1 is handled below; here, we diagnose the case where 1122 // we have an initializer list and a destination type that is not 1123 // an aggregate. 1124 // FIXME: In C++0x, this is yet another form of initialization. 1125 if (const RecordType *ClassRec = DeclType->getAsRecordType()) { 1126 const CXXRecordDecl *ClassDecl = cast<CXXRecordDecl>(ClassRec->getDecl()); 1127 if (!ClassDecl->isAggregate()) 1128 return Diag(InitLoc, diag::err_init_non_aggr_init_list) 1129 << DeclType << Init->getSourceRange(); 1130 } 1131 } 1132 1133 InitListChecker CheckInitList(this, InitList, DeclType); 1134 return CheckInitList.HadError(); 1135} 1136 1137/// GetNameForDeclarator - Determine the full declaration name for the 1138/// given Declarator. 1139DeclarationName Sema::GetNameForDeclarator(Declarator &D) { 1140 switch (D.getKind()) { 1141 case Declarator::DK_Abstract: 1142 assert(D.getIdentifier() == 0 && "abstract declarators have no name"); 1143 return DeclarationName(); 1144 1145 case Declarator::DK_Normal: 1146 assert (D.getIdentifier() != 0 && "normal declarators have an identifier"); 1147 return DeclarationName(D.getIdentifier()); 1148 1149 case Declarator::DK_Constructor: { 1150 QualType Ty = Context.getTypeDeclType((TypeDecl *)D.getDeclaratorIdType()); 1151 Ty = Context.getCanonicalType(Ty); 1152 return Context.DeclarationNames.getCXXConstructorName(Ty); 1153 } 1154 1155 case Declarator::DK_Destructor: { 1156 QualType Ty = Context.getTypeDeclType((TypeDecl *)D.getDeclaratorIdType()); 1157 Ty = Context.getCanonicalType(Ty); 1158 return Context.DeclarationNames.getCXXDestructorName(Ty); 1159 } 1160 1161 case Declarator::DK_Conversion: { 1162 QualType Ty = QualType::getFromOpaquePtr(D.getDeclaratorIdType()); 1163 Ty = Context.getCanonicalType(Ty); 1164 return Context.DeclarationNames.getCXXConversionFunctionName(Ty); 1165 } 1166 1167 case Declarator::DK_Operator: 1168 assert(D.getIdentifier() == 0 && "operator names have no identifier"); 1169 return Context.DeclarationNames.getCXXOperatorName( 1170 D.getOverloadedOperator()); 1171 } 1172 1173 assert(false && "Unknown name kind"); 1174 return DeclarationName(); 1175} 1176 1177/// isNearlyMatchingMemberFunction - Determine whether the C++ member 1178/// functions Declaration and Definition are "nearly" matching. This 1179/// heuristic is used to improve diagnostics in the case where an 1180/// out-of-line member function definition doesn't match any 1181/// declaration within the class. 1182static bool isNearlyMatchingMemberFunction(ASTContext &Context, 1183 FunctionDecl *Declaration, 1184 FunctionDecl *Definition) { 1185 if (Declaration->param_size() != Definition->param_size()) 1186 return false; 1187 for (unsigned Idx = 0; Idx < Declaration->param_size(); ++Idx) { 1188 QualType DeclParamTy = Declaration->getParamDecl(Idx)->getType(); 1189 QualType DefParamTy = Definition->getParamDecl(Idx)->getType(); 1190 1191 DeclParamTy = Context.getCanonicalType(DeclParamTy.getNonReferenceType()); 1192 DefParamTy = Context.getCanonicalType(DefParamTy.getNonReferenceType()); 1193 if (DeclParamTy.getUnqualifiedType() != DefParamTy.getUnqualifiedType()) 1194 return false; 1195 } 1196 1197 return true; 1198} 1199 1200Sema::DeclTy * 1201Sema::ActOnDeclarator(Scope *S, Declarator &D, DeclTy *lastDecl, 1202 bool IsFunctionDefinition) { 1203 ScopedDecl *LastDeclarator = dyn_cast_or_null<ScopedDecl>((Decl *)lastDecl); 1204 DeclarationName Name = GetNameForDeclarator(D); 1205 1206 // All of these full declarators require an identifier. If it doesn't have 1207 // one, the ParsedFreeStandingDeclSpec action should be used. 1208 if (!Name) { 1209 if (!D.getInvalidType()) // Reject this if we think it is valid. 1210 Diag(D.getDeclSpec().getSourceRange().getBegin(), 1211 diag::err_declarator_need_ident) 1212 << D.getDeclSpec().getSourceRange() << D.getSourceRange(); 1213 return 0; 1214 } 1215 1216 // The scope passed in may not be a decl scope. Zip up the scope tree until 1217 // we find one that is. 1218 while ((S->getFlags() & Scope::DeclScope) == 0 || 1219 (S->getFlags() & Scope::TemplateParamScope) != 0) 1220 S = S->getParent(); 1221 1222 DeclContext *DC; 1223 Decl *PrevDecl; 1224 ScopedDecl *New; 1225 bool InvalidDecl = false; 1226 1227 // See if this is a redefinition of a variable in the same scope. 1228 if (!D.getCXXScopeSpec().isSet()) { 1229 DC = CurContext; 1230 PrevDecl = LookupDecl(Name, Decl::IDNS_Ordinary, S); 1231 } else { // Something like "int foo::x;" 1232 DC = static_cast<DeclContext*>(D.getCXXScopeSpec().getScopeRep()); 1233 PrevDecl = LookupDecl(Name, Decl::IDNS_Ordinary, S, DC); 1234 1235 // C++ 7.3.1.2p2: 1236 // Members (including explicit specializations of templates) of a named 1237 // namespace can also be defined outside that namespace by explicit 1238 // qualification of the name being defined, provided that the entity being 1239 // defined was already declared in the namespace and the definition appears 1240 // after the point of declaration in a namespace that encloses the 1241 // declarations namespace. 1242 // 1243 // Note that we only check the context at this point. We don't yet 1244 // have enough information to make sure that PrevDecl is actually 1245 // the declaration we want to match. For example, given: 1246 // 1247 // class X { 1248 // void f(); 1249 // void f(float); 1250 // }; 1251 // 1252 // void X::f(int) { } // ill-formed 1253 // 1254 // In this case, PrevDecl will point to the overload set 1255 // containing the two f's declared in X, but neither of them 1256 // matches. 1257 if (!CurContext->Encloses(DC)) { 1258 // The qualifying scope doesn't enclose the original declaration. 1259 // Emit diagnostic based on current scope. 1260 SourceLocation L = D.getIdentifierLoc(); 1261 SourceRange R = D.getCXXScopeSpec().getRange(); 1262 if (isa<FunctionDecl>(CurContext)) { 1263 Diag(L, diag::err_invalid_declarator_in_function) << Name << R; 1264 } else { 1265 Diag(L, diag::err_invalid_declarator_scope) 1266 << Name << cast<NamedDecl>(DC)->getDeclName() << R; 1267 } 1268 InvalidDecl = true; 1269 } 1270 } 1271 1272 if (PrevDecl && PrevDecl->isTemplateParameter()) { 1273 // Maybe we will complain about the shadowed template parameter. 1274 InvalidDecl = InvalidDecl 1275 || DiagnoseTemplateParameterShadow(D.getIdentifierLoc(), PrevDecl); 1276 // Just pretend that we didn't see the previous declaration. 1277 PrevDecl = 0; 1278 } 1279 1280 // In C++, the previous declaration we find might be a tag type 1281 // (class or enum). In this case, the new declaration will hide the 1282 // tag type. 1283 if (PrevDecl && PrevDecl->getIdentifierNamespace() == Decl::IDNS_Tag) 1284 PrevDecl = 0; 1285 1286 QualType R = GetTypeForDeclarator(D, S); 1287 assert(!R.isNull() && "GetTypeForDeclarator() returned null type"); 1288 1289 if (D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_typedef) { 1290 New = ActOnTypedefDeclarator(S, D, DC, R, LastDeclarator, PrevDecl, 1291 InvalidDecl); 1292 } else if (R.getTypePtr()->isFunctionType()) { 1293 New = ActOnFunctionDeclarator(S, D, DC, R, LastDeclarator, PrevDecl, 1294 IsFunctionDefinition, InvalidDecl); 1295 } else { 1296 New = ActOnVariableDeclarator(S, D, DC, R, LastDeclarator, PrevDecl, 1297 InvalidDecl); 1298 } 1299 1300 if (New == 0) 1301 return 0; 1302 1303 // Set the lexical context. If the declarator has a C++ scope specifier, the 1304 // lexical context will be different from the semantic context. 1305 New->setLexicalDeclContext(CurContext); 1306 1307 // If this has an identifier, add it to the scope stack. 1308 if (Name) 1309 PushOnScopeChains(New, S); 1310 // If any semantic error occurred, mark the decl as invalid. 1311 if (D.getInvalidType() || InvalidDecl) 1312 New->setInvalidDecl(); 1313 1314 return New; 1315} 1316 1317ScopedDecl* 1318Sema::ActOnTypedefDeclarator(Scope* S, Declarator& D, DeclContext* DC, 1319 QualType R, ScopedDecl* LastDeclarator, 1320 Decl* PrevDecl, bool& InvalidDecl) { 1321 // Typedef declarators cannot be qualified (C++ [dcl.meaning]p1). 1322 if (D.getCXXScopeSpec().isSet()) { 1323 Diag(D.getIdentifierLoc(), diag::err_qualified_typedef_declarator) 1324 << D.getCXXScopeSpec().getRange(); 1325 InvalidDecl = true; 1326 // Pretend we didn't see the scope specifier. 1327 DC = 0; 1328 } 1329 1330 // Check that there are no default arguments (C++ only). 1331 if (getLangOptions().CPlusPlus) 1332 CheckExtraCXXDefaultArguments(D); 1333 1334 TypedefDecl *NewTD = ParseTypedefDecl(S, D, R, LastDeclarator); 1335 if (!NewTD) return 0; 1336 1337 // Handle attributes prior to checking for duplicates in MergeVarDecl 1338 ProcessDeclAttributes(NewTD, D); 1339 // Merge the decl with the existing one if appropriate. If the decl is 1340 // in an outer scope, it isn't the same thing. 1341 if (PrevDecl && isDeclInScope(PrevDecl, DC, S)) { 1342 NewTD = MergeTypeDefDecl(NewTD, PrevDecl); 1343 if (NewTD == 0) return 0; 1344 } 1345 1346 if (S->getFnParent() == 0) { 1347 // C99 6.7.7p2: If a typedef name specifies a variably modified type 1348 // then it shall have block scope. 1349 if (NewTD->getUnderlyingType()->isVariablyModifiedType()) { 1350 if (NewTD->getUnderlyingType()->isVariableArrayType()) 1351 Diag(D.getIdentifierLoc(), diag::err_vla_decl_in_file_scope); 1352 else 1353 Diag(D.getIdentifierLoc(), diag::err_vm_decl_in_file_scope); 1354 1355 InvalidDecl = true; 1356 } 1357 } 1358 return NewTD; 1359} 1360 1361ScopedDecl* 1362Sema::ActOnVariableDeclarator(Scope* S, Declarator& D, DeclContext* DC, 1363 QualType R, ScopedDecl* LastDeclarator, 1364 Decl* PrevDecl, bool& InvalidDecl) { 1365 DeclarationName Name = GetNameForDeclarator(D); 1366 1367 // Check that there are no default arguments (C++ only). 1368 if (getLangOptions().CPlusPlus) 1369 CheckExtraCXXDefaultArguments(D); 1370 1371 if (R.getTypePtr()->isObjCInterfaceType()) { 1372 Diag(D.getIdentifierLoc(), diag::err_statically_allocated_object) 1373 << D.getIdentifier(); 1374 InvalidDecl = true; 1375 } 1376 1377 VarDecl *NewVD; 1378 VarDecl::StorageClass SC; 1379 switch (D.getDeclSpec().getStorageClassSpec()) { 1380 default: assert(0 && "Unknown storage class!"); 1381 case DeclSpec::SCS_unspecified: SC = VarDecl::None; break; 1382 case DeclSpec::SCS_extern: SC = VarDecl::Extern; break; 1383 case DeclSpec::SCS_static: SC = VarDecl::Static; break; 1384 case DeclSpec::SCS_auto: SC = VarDecl::Auto; break; 1385 case DeclSpec::SCS_register: SC = VarDecl::Register; break; 1386 case DeclSpec::SCS_private_extern: SC = VarDecl::PrivateExtern; break; 1387 case DeclSpec::SCS_mutable: 1388 // mutable can only appear on non-static class members, so it's always 1389 // an error here 1390 Diag(D.getIdentifierLoc(), diag::err_mutable_nonmember); 1391 InvalidDecl = true; 1392 SC = VarDecl::None; 1393 break; 1394 } 1395 1396 IdentifierInfo *II = Name.getAsIdentifierInfo(); 1397 if (!II) { 1398 Diag(D.getIdentifierLoc(), diag::err_bad_variable_name) 1399 << Name.getAsString(); 1400 return 0; 1401 } 1402 1403 if (DC->isRecord()) { 1404 // This is a static data member for a C++ class. 1405 NewVD = CXXClassVarDecl::Create(Context, cast<CXXRecordDecl>(DC), 1406 D.getIdentifierLoc(), II, 1407 R, LastDeclarator); 1408 } else { 1409 bool ThreadSpecified = D.getDeclSpec().isThreadSpecified(); 1410 if (S->getFnParent() == 0) { 1411 // C99 6.9p2: The storage-class specifiers auto and register shall not 1412 // appear in the declaration specifiers in an external declaration. 1413 if (SC == VarDecl::Auto || SC == VarDecl::Register) { 1414 Diag(D.getIdentifierLoc(), diag::err_typecheck_sclass_fscope); 1415 InvalidDecl = true; 1416 } 1417 } 1418 NewVD = VarDecl::Create(Context, DC, D.getIdentifierLoc(), 1419 II, R, SC, LastDeclarator, 1420 // FIXME: Move to DeclGroup... 1421 D.getDeclSpec().getSourceRange().getBegin()); 1422 NewVD->setThreadSpecified(ThreadSpecified); 1423 } 1424 // Handle attributes prior to checking for duplicates in MergeVarDecl 1425 ProcessDeclAttributes(NewVD, D); 1426 1427 // Handle GNU asm-label extension (encoded as an attribute). 1428 if (Expr *E = (Expr*) D.getAsmLabel()) { 1429 // The parser guarantees this is a string. 1430 StringLiteral *SE = cast<StringLiteral>(E); 1431 NewVD->addAttr(new AsmLabelAttr(std::string(SE->getStrData(), 1432 SE->getByteLength()))); 1433 } 1434 1435 // Emit an error if an address space was applied to decl with local storage. 1436 // This includes arrays of objects with address space qualifiers, but not 1437 // automatic variables that point to other address spaces. 1438 // ISO/IEC TR 18037 S5.1.2 1439 if (NewVD->hasLocalStorage() && (NewVD->getType().getAddressSpace() != 0)) { 1440 Diag(D.getIdentifierLoc(), diag::err_as_qualified_auto_decl); 1441 InvalidDecl = true; 1442 } 1443 // Merge the decl with the existing one if appropriate. If the decl is 1444 // in an outer scope, it isn't the same thing. 1445 if (PrevDecl && isDeclInScope(PrevDecl, DC, S)) { 1446 if (isa<FieldDecl>(PrevDecl) && D.getCXXScopeSpec().isSet()) { 1447 // The user tried to define a non-static data member 1448 // out-of-line (C++ [dcl.meaning]p1). 1449 Diag(NewVD->getLocation(), diag::err_nonstatic_member_out_of_line) 1450 << D.getCXXScopeSpec().getRange(); 1451 NewVD->Destroy(Context); 1452 return 0; 1453 } 1454 1455 NewVD = MergeVarDecl(NewVD, PrevDecl); 1456 if (NewVD == 0) return 0; 1457 1458 if (D.getCXXScopeSpec().isSet()) { 1459 // No previous declaration in the qualifying scope. 1460 Diag(D.getIdentifierLoc(), diag::err_typecheck_no_member) 1461 << Name << D.getCXXScopeSpec().getRange(); 1462 InvalidDecl = true; 1463 } 1464 } 1465 return NewVD; 1466} 1467 1468ScopedDecl* 1469Sema::ActOnFunctionDeclarator(Scope* S, Declarator& D, DeclContext* DC, 1470 QualType R, ScopedDecl *LastDeclarator, 1471 Decl* PrevDecl, bool IsFunctionDefinition, 1472 bool& InvalidDecl) { 1473 assert(R.getTypePtr()->isFunctionType()); 1474 1475 DeclarationName Name = GetNameForDeclarator(D); 1476 FunctionDecl::StorageClass SC = FunctionDecl::None; 1477 switch (D.getDeclSpec().getStorageClassSpec()) { 1478 default: assert(0 && "Unknown storage class!"); 1479 case DeclSpec::SCS_auto: 1480 case DeclSpec::SCS_register: 1481 case DeclSpec::SCS_mutable: 1482 Diag(D.getIdentifierLoc(), diag::err_typecheck_sclass_func); 1483 InvalidDecl = true; 1484 break; 1485 case DeclSpec::SCS_unspecified: SC = FunctionDecl::None; break; 1486 case DeclSpec::SCS_extern: SC = FunctionDecl::Extern; break; 1487 case DeclSpec::SCS_static: SC = FunctionDecl::Static; break; 1488 case DeclSpec::SCS_private_extern: SC = FunctionDecl::PrivateExtern;break; 1489 } 1490 1491 bool isInline = D.getDeclSpec().isInlineSpecified(); 1492 // bool isVirtual = D.getDeclSpec().isVirtualSpecified(); 1493 bool isExplicit = D.getDeclSpec().isExplicitSpecified(); 1494 1495 FunctionDecl *NewFD; 1496 if (D.getKind() == Declarator::DK_Constructor) { 1497 // This is a C++ constructor declaration. 1498 assert(DC->isRecord() && 1499 "Constructors can only be declared in a member context"); 1500 1501 InvalidDecl = InvalidDecl || CheckConstructorDeclarator(D, R, SC); 1502 1503 // Create the new declaration 1504 NewFD = CXXConstructorDecl::Create(Context, 1505 cast<CXXRecordDecl>(DC), 1506 D.getIdentifierLoc(), Name, R, 1507 isExplicit, isInline, 1508 /*isImplicitlyDeclared=*/false); 1509 1510 if (InvalidDecl) 1511 NewFD->setInvalidDecl(); 1512 } else if (D.getKind() == Declarator::DK_Destructor) { 1513 // This is a C++ destructor declaration. 1514 if (DC->isRecord()) { 1515 InvalidDecl = InvalidDecl || CheckDestructorDeclarator(D, R, SC); 1516 1517 NewFD = CXXDestructorDecl::Create(Context, 1518 cast<CXXRecordDecl>(DC), 1519 D.getIdentifierLoc(), Name, R, 1520 isInline, 1521 /*isImplicitlyDeclared=*/false); 1522 1523 if (InvalidDecl) 1524 NewFD->setInvalidDecl(); 1525 } else { 1526 Diag(D.getIdentifierLoc(), diag::err_destructor_not_member); 1527 1528 // Create a FunctionDecl to satisfy the function definition parsing 1529 // code path. 1530 NewFD = FunctionDecl::Create(Context, DC, D.getIdentifierLoc(), 1531 Name, R, SC, isInline, LastDeclarator, 1532 // FIXME: Move to DeclGroup... 1533 D.getDeclSpec().getSourceRange().getBegin()); 1534 InvalidDecl = true; 1535 NewFD->setInvalidDecl(); 1536 } 1537 } else if (D.getKind() == Declarator::DK_Conversion) { 1538 if (!DC->isRecord()) { 1539 Diag(D.getIdentifierLoc(), 1540 diag::err_conv_function_not_member); 1541 return 0; 1542 } else { 1543 InvalidDecl = InvalidDecl || CheckConversionDeclarator(D, R, SC); 1544 1545 NewFD = CXXConversionDecl::Create(Context, cast<CXXRecordDecl>(DC), 1546 D.getIdentifierLoc(), Name, R, 1547 isInline, isExplicit); 1548 1549 if (InvalidDecl) 1550 NewFD->setInvalidDecl(); 1551 } 1552 } else if (DC->isRecord()) { 1553 // This is a C++ method declaration. 1554 NewFD = CXXMethodDecl::Create(Context, cast<CXXRecordDecl>(DC), 1555 D.getIdentifierLoc(), Name, R, 1556 (SC == FunctionDecl::Static), isInline, 1557 LastDeclarator); 1558 } else { 1559 NewFD = FunctionDecl::Create(Context, DC, 1560 D.getIdentifierLoc(), 1561 Name, R, SC, isInline, LastDeclarator, 1562 // FIXME: Move to DeclGroup... 1563 D.getDeclSpec().getSourceRange().getBegin()); 1564 } 1565 1566 // Set the lexical context. If the declarator has a C++ 1567 // scope specifier, the lexical context will be different 1568 // from the semantic context. 1569 NewFD->setLexicalDeclContext(CurContext); 1570 1571 // Handle GNU asm-label extension (encoded as an attribute). 1572 if (Expr *E = (Expr*) D.getAsmLabel()) { 1573 // The parser guarantees this is a string. 1574 StringLiteral *SE = cast<StringLiteral>(E); 1575 NewFD->addAttr(new AsmLabelAttr(std::string(SE->getStrData(), 1576 SE->getByteLength()))); 1577 } 1578 1579 // Copy the parameter declarations from the declarator D to 1580 // the function declaration NewFD, if they are available. 1581 if (D.getNumTypeObjects() > 0) { 1582 DeclaratorChunk::FunctionTypeInfo &FTI = D.getTypeObject(0).Fun; 1583 1584 // Create Decl objects for each parameter, adding them to the 1585 // FunctionDecl. 1586 llvm::SmallVector<ParmVarDecl*, 16> Params; 1587 1588 // Check for C99 6.7.5.3p10 - foo(void) is a non-varargs 1589 // function that takes no arguments, not a function that takes a 1590 // single void argument. 1591 // We let through "const void" here because Sema::GetTypeForDeclarator 1592 // already checks for that case. 1593 if (FTI.NumArgs == 1 && !FTI.isVariadic && FTI.ArgInfo[0].Ident == 0 && 1594 FTI.ArgInfo[0].Param && 1595 ((ParmVarDecl*)FTI.ArgInfo[0].Param)->getType()->isVoidType()) { 1596 // empty arg list, don't push any params. 1597 ParmVarDecl *Param = (ParmVarDecl*)FTI.ArgInfo[0].Param; 1598 1599 // In C++, the empty parameter-type-list must be spelled "void"; a 1600 // typedef of void is not permitted. 1601 if (getLangOptions().CPlusPlus && 1602 Param->getType().getUnqualifiedType() != Context.VoidTy) { 1603 Diag(Param->getLocation(), diag::ext_param_typedef_of_void); 1604 } 1605 } else if (FTI.NumArgs > 0 && FTI.ArgInfo[0].Param != 0) { 1606 for (unsigned i = 0, e = FTI.NumArgs; i != e; ++i) 1607 Params.push_back((ParmVarDecl *)FTI.ArgInfo[i].Param); 1608 } 1609 1610 NewFD->setParams(Context, &Params[0], Params.size()); 1611 } else if (R->getAsTypedefType()) { 1612 // When we're declaring a function with a typedef, as in the 1613 // following example, we'll need to synthesize (unnamed) 1614 // parameters for use in the declaration. 1615 // 1616 // @code 1617 // typedef void fn(int); 1618 // fn f; 1619 // @endcode 1620 const FunctionTypeProto *FT = R->getAsFunctionTypeProto(); 1621 if (!FT) { 1622 // This is a typedef of a function with no prototype, so we 1623 // don't need to do anything. 1624 } else if ((FT->getNumArgs() == 0) || 1625 (FT->getNumArgs() == 1 && !FT->isVariadic() && 1626 FT->getArgType(0)->isVoidType())) { 1627 // This is a zero-argument function. We don't need to do anything. 1628 } else { 1629 // Synthesize a parameter for each argument type. 1630 llvm::SmallVector<ParmVarDecl*, 16> Params; 1631 for (FunctionTypeProto::arg_type_iterator ArgType = FT->arg_type_begin(); 1632 ArgType != FT->arg_type_end(); ++ArgType) { 1633 Params.push_back(ParmVarDecl::Create(Context, DC, 1634 SourceLocation(), 0, 1635 *ArgType, VarDecl::None, 1636 0, 0)); 1637 } 1638 1639 NewFD->setParams(Context, &Params[0], Params.size()); 1640 } 1641 } 1642 1643 if (CXXConstructorDecl *Constructor = dyn_cast<CXXConstructorDecl>(NewFD)) 1644 InvalidDecl = InvalidDecl || CheckConstructor(Constructor); 1645 else if (isa<CXXDestructorDecl>(NewFD)) { 1646 CXXRecordDecl *Record = cast<CXXRecordDecl>(NewFD->getParent()); 1647 Record->setUserDeclaredDestructor(true); 1648 // C++ [class]p4: A POD-struct is an aggregate class that has [...] no 1649 // user-defined destructor. 1650 Record->setPOD(false); 1651 } else if (CXXConversionDecl *Conversion = 1652 dyn_cast<CXXConversionDecl>(NewFD)) 1653 ActOnConversionDeclarator(Conversion); 1654 1655 // Extra checking for C++ overloaded operators (C++ [over.oper]). 1656 if (NewFD->isOverloadedOperator() && 1657 CheckOverloadedOperatorDeclaration(NewFD)) 1658 NewFD->setInvalidDecl(); 1659 1660 // Merge the decl with the existing one if appropriate. Since C functions 1661 // are in a flat namespace, make sure we consider decls in outer scopes. 1662 if (PrevDecl && 1663 (!getLangOptions().CPlusPlus||isDeclInScope(PrevDecl, DC, S))) { 1664 bool Redeclaration = false; 1665 1666 // If C++, determine whether NewFD is an overload of PrevDecl or 1667 // a declaration that requires merging. If it's an overload, 1668 // there's no more work to do here; we'll just add the new 1669 // function to the scope. 1670 OverloadedFunctionDecl::function_iterator MatchedDecl; 1671 if (!getLangOptions().CPlusPlus || 1672 !IsOverload(NewFD, PrevDecl, MatchedDecl)) { 1673 Decl *OldDecl = PrevDecl; 1674 1675 // If PrevDecl was an overloaded function, extract the 1676 // FunctionDecl that matched. 1677 if (isa<OverloadedFunctionDecl>(PrevDecl)) 1678 OldDecl = *MatchedDecl; 1679 1680 // NewFD and PrevDecl represent declarations that need to be 1681 // merged. 1682 NewFD = MergeFunctionDecl(NewFD, OldDecl, Redeclaration); 1683 1684 if (NewFD == 0) return 0; 1685 if (Redeclaration) { 1686 NewFD->setPreviousDeclaration(cast<FunctionDecl>(OldDecl)); 1687 1688 // An out-of-line member function declaration must also be a 1689 // definition (C++ [dcl.meaning]p1). 1690 if (!IsFunctionDefinition && D.getCXXScopeSpec().isSet() && 1691 !InvalidDecl) { 1692 Diag(NewFD->getLocation(), diag::err_out_of_line_declaration) 1693 << D.getCXXScopeSpec().getRange(); 1694 NewFD->setInvalidDecl(); 1695 } 1696 } 1697 } 1698 1699 if (!Redeclaration && D.getCXXScopeSpec().isSet()) { 1700 // The user tried to provide an out-of-line definition for a 1701 // member function, but there was no such member function 1702 // declared (C++ [class.mfct]p2). For example: 1703 // 1704 // class X { 1705 // void f() const; 1706 // }; 1707 // 1708 // void X::f() { } // ill-formed 1709 // 1710 // Complain about this problem, and attempt to suggest close 1711 // matches (e.g., those that differ only in cv-qualifiers and 1712 // whether the parameter types are references). 1713 Diag(D.getIdentifierLoc(), diag::err_member_def_does_not_match) 1714 << cast<CXXRecordDecl>(DC)->getDeclName() 1715 << D.getCXXScopeSpec().getRange(); 1716 InvalidDecl = true; 1717 1718 PrevDecl = LookupDecl(Name, Decl::IDNS_Ordinary, S, DC); 1719 if (!PrevDecl) { 1720 // Nothing to suggest. 1721 } else if (OverloadedFunctionDecl *Ovl 1722 = dyn_cast<OverloadedFunctionDecl>(PrevDecl)) { 1723 for (OverloadedFunctionDecl::function_iterator 1724 Func = Ovl->function_begin(), 1725 FuncEnd = Ovl->function_end(); 1726 Func != FuncEnd; ++Func) { 1727 if (isNearlyMatchingMemberFunction(Context, *Func, NewFD)) 1728 Diag((*Func)->getLocation(), diag::note_member_def_close_match); 1729 1730 } 1731 } else if (CXXMethodDecl *Method = dyn_cast<CXXMethodDecl>(PrevDecl)) { 1732 // Suggest this no matter how mismatched it is; it's the only 1733 // thing we have. 1734 unsigned diag; 1735 if (isNearlyMatchingMemberFunction(Context, Method, NewFD)) 1736 diag = diag::note_member_def_close_match; 1737 else if (Method->getBody()) 1738 diag = diag::note_previous_definition; 1739 else 1740 diag = diag::note_previous_declaration; 1741 Diag(Method->getLocation(), diag); 1742 } 1743 1744 PrevDecl = 0; 1745 } 1746 } 1747 // Handle attributes. We need to have merged decls when handling attributes 1748 // (for example to check for conflicts, etc). 1749 ProcessDeclAttributes(NewFD, D); 1750 1751 if (getLangOptions().CPlusPlus) { 1752 // In C++, check default arguments now that we have merged decls. 1753 CheckCXXDefaultArguments(NewFD); 1754 1755 // An out-of-line member function declaration must also be a 1756 // definition (C++ [dcl.meaning]p1). 1757 if (!IsFunctionDefinition && D.getCXXScopeSpec().isSet() && !InvalidDecl) { 1758 Diag(NewFD->getLocation(), diag::err_out_of_line_declaration) 1759 << D.getCXXScopeSpec().getRange(); 1760 InvalidDecl = true; 1761 } 1762 } 1763 return NewFD; 1764} 1765 1766void Sema::InitializerElementNotConstant(const Expr *Init) { 1767 Diag(Init->getExprLoc(), diag::err_init_element_not_constant) 1768 << Init->getSourceRange(); 1769} 1770 1771bool Sema::CheckAddressConstantExpressionLValue(const Expr* Init) { 1772 switch (Init->getStmtClass()) { 1773 default: 1774 InitializerElementNotConstant(Init); 1775 return true; 1776 case Expr::ParenExprClass: { 1777 const ParenExpr* PE = cast<ParenExpr>(Init); 1778 return CheckAddressConstantExpressionLValue(PE->getSubExpr()); 1779 } 1780 case Expr::CompoundLiteralExprClass: 1781 return cast<CompoundLiteralExpr>(Init)->isFileScope(); 1782 case Expr::DeclRefExprClass: 1783 case Expr::QualifiedDeclRefExprClass: { 1784 const Decl *D = cast<DeclRefExpr>(Init)->getDecl(); 1785 if (const VarDecl *VD = dyn_cast<VarDecl>(D)) { 1786 if (VD->hasGlobalStorage()) 1787 return false; 1788 InitializerElementNotConstant(Init); 1789 return true; 1790 } 1791 if (isa<FunctionDecl>(D)) 1792 return false; 1793 InitializerElementNotConstant(Init); 1794 return true; 1795 } 1796 case Expr::MemberExprClass: { 1797 const MemberExpr *M = cast<MemberExpr>(Init); 1798 if (M->isArrow()) 1799 return CheckAddressConstantExpression(M->getBase()); 1800 return CheckAddressConstantExpressionLValue(M->getBase()); 1801 } 1802 case Expr::ArraySubscriptExprClass: { 1803 // FIXME: Should we pedwarn for "x[0+0]" (where x is a pointer)? 1804 const ArraySubscriptExpr *ASE = cast<ArraySubscriptExpr>(Init); 1805 return CheckAddressConstantExpression(ASE->getBase()) || 1806 CheckArithmeticConstantExpression(ASE->getIdx()); 1807 } 1808 case Expr::StringLiteralClass: 1809 case Expr::PredefinedExprClass: 1810 return false; 1811 case Expr::UnaryOperatorClass: { 1812 const UnaryOperator *Exp = cast<UnaryOperator>(Init); 1813 1814 // C99 6.6p9 1815 if (Exp->getOpcode() == UnaryOperator::Deref) 1816 return CheckAddressConstantExpression(Exp->getSubExpr()); 1817 1818 InitializerElementNotConstant(Init); 1819 return true; 1820 } 1821 } 1822} 1823 1824bool Sema::CheckAddressConstantExpression(const Expr* Init) { 1825 switch (Init->getStmtClass()) { 1826 default: 1827 InitializerElementNotConstant(Init); 1828 return true; 1829 case Expr::ParenExprClass: 1830 return CheckAddressConstantExpression(cast<ParenExpr>(Init)->getSubExpr()); 1831 case Expr::StringLiteralClass: 1832 case Expr::ObjCStringLiteralClass: 1833 return false; 1834 case Expr::CallExprClass: 1835 case Expr::CXXOperatorCallExprClass: 1836 // __builtin___CFStringMakeConstantString is a valid constant l-value. 1837 if (cast<CallExpr>(Init)->isBuiltinCall() == 1838 Builtin::BI__builtin___CFStringMakeConstantString) 1839 return false; 1840 1841 InitializerElementNotConstant(Init); 1842 return true; 1843 1844 case Expr::UnaryOperatorClass: { 1845 const UnaryOperator *Exp = cast<UnaryOperator>(Init); 1846 1847 // C99 6.6p9 1848 if (Exp->getOpcode() == UnaryOperator::AddrOf) 1849 return CheckAddressConstantExpressionLValue(Exp->getSubExpr()); 1850 1851 if (Exp->getOpcode() == UnaryOperator::Extension) 1852 return CheckAddressConstantExpression(Exp->getSubExpr()); 1853 1854 InitializerElementNotConstant(Init); 1855 return true; 1856 } 1857 case Expr::BinaryOperatorClass: { 1858 // FIXME: Should we pedwarn for expressions like "a + 1 + 2"? 1859 const BinaryOperator *Exp = cast<BinaryOperator>(Init); 1860 1861 Expr *PExp = Exp->getLHS(); 1862 Expr *IExp = Exp->getRHS(); 1863 if (IExp->getType()->isPointerType()) 1864 std::swap(PExp, IExp); 1865 1866 // FIXME: Should we pedwarn if IExp isn't an integer constant expression? 1867 return CheckAddressConstantExpression(PExp) || 1868 CheckArithmeticConstantExpression(IExp); 1869 } 1870 case Expr::ImplicitCastExprClass: 1871 case Expr::CStyleCastExprClass: { 1872 const Expr* SubExpr = cast<CastExpr>(Init)->getSubExpr(); 1873 if (Init->getStmtClass() == Expr::ImplicitCastExprClass) { 1874 // Check for implicit promotion 1875 if (SubExpr->getType()->isFunctionType() || 1876 SubExpr->getType()->isArrayType()) 1877 return CheckAddressConstantExpressionLValue(SubExpr); 1878 } 1879 1880 // Check for pointer->pointer cast 1881 if (SubExpr->getType()->isPointerType()) 1882 return CheckAddressConstantExpression(SubExpr); 1883 1884 if (SubExpr->getType()->isIntegralType()) { 1885 // Check for the special-case of a pointer->int->pointer cast; 1886 // this isn't standard, but some code requires it. See 1887 // PR2720 for an example. 1888 if (const CastExpr* SubCast = dyn_cast<CastExpr>(SubExpr)) { 1889 if (SubCast->getSubExpr()->getType()->isPointerType()) { 1890 unsigned IntWidth = Context.getIntWidth(SubCast->getType()); 1891 unsigned PointerWidth = Context.getTypeSize(Context.VoidPtrTy); 1892 if (IntWidth >= PointerWidth) { 1893 return CheckAddressConstantExpression(SubCast->getSubExpr()); 1894 } 1895 } 1896 } 1897 } 1898 if (SubExpr->getType()->isArithmeticType()) { 1899 return CheckArithmeticConstantExpression(SubExpr); 1900 } 1901 1902 InitializerElementNotConstant(Init); 1903 return true; 1904 } 1905 case Expr::ConditionalOperatorClass: { 1906 // FIXME: Should we pedwarn here? 1907 const ConditionalOperator *Exp = cast<ConditionalOperator>(Init); 1908 if (!Exp->getCond()->getType()->isArithmeticType()) { 1909 InitializerElementNotConstant(Init); 1910 return true; 1911 } 1912 if (CheckArithmeticConstantExpression(Exp->getCond())) 1913 return true; 1914 if (Exp->getLHS() && 1915 CheckAddressConstantExpression(Exp->getLHS())) 1916 return true; 1917 return CheckAddressConstantExpression(Exp->getRHS()); 1918 } 1919 case Expr::AddrLabelExprClass: 1920 return false; 1921 } 1922} 1923 1924static const Expr* FindExpressionBaseAddress(const Expr* E); 1925 1926static const Expr* FindExpressionBaseAddressLValue(const Expr* E) { 1927 switch (E->getStmtClass()) { 1928 default: 1929 return E; 1930 case Expr::ParenExprClass: { 1931 const ParenExpr* PE = cast<ParenExpr>(E); 1932 return FindExpressionBaseAddressLValue(PE->getSubExpr()); 1933 } 1934 case Expr::MemberExprClass: { 1935 const MemberExpr *M = cast<MemberExpr>(E); 1936 if (M->isArrow()) 1937 return FindExpressionBaseAddress(M->getBase()); 1938 return FindExpressionBaseAddressLValue(M->getBase()); 1939 } 1940 case Expr::ArraySubscriptExprClass: { 1941 const ArraySubscriptExpr *ASE = cast<ArraySubscriptExpr>(E); 1942 return FindExpressionBaseAddress(ASE->getBase()); 1943 } 1944 case Expr::UnaryOperatorClass: { 1945 const UnaryOperator *Exp = cast<UnaryOperator>(E); 1946 1947 if (Exp->getOpcode() == UnaryOperator::Deref) 1948 return FindExpressionBaseAddress(Exp->getSubExpr()); 1949 1950 return E; 1951 } 1952 } 1953} 1954 1955static const Expr* FindExpressionBaseAddress(const Expr* E) { 1956 switch (E->getStmtClass()) { 1957 default: 1958 return E; 1959 case Expr::ParenExprClass: { 1960 const ParenExpr* PE = cast<ParenExpr>(E); 1961 return FindExpressionBaseAddress(PE->getSubExpr()); 1962 } 1963 case Expr::UnaryOperatorClass: { 1964 const UnaryOperator *Exp = cast<UnaryOperator>(E); 1965 1966 // C99 6.6p9 1967 if (Exp->getOpcode() == UnaryOperator::AddrOf) 1968 return FindExpressionBaseAddressLValue(Exp->getSubExpr()); 1969 1970 if (Exp->getOpcode() == UnaryOperator::Extension) 1971 return FindExpressionBaseAddress(Exp->getSubExpr()); 1972 1973 return E; 1974 } 1975 case Expr::BinaryOperatorClass: { 1976 const BinaryOperator *Exp = cast<BinaryOperator>(E); 1977 1978 Expr *PExp = Exp->getLHS(); 1979 Expr *IExp = Exp->getRHS(); 1980 if (IExp->getType()->isPointerType()) 1981 std::swap(PExp, IExp); 1982 1983 return FindExpressionBaseAddress(PExp); 1984 } 1985 case Expr::ImplicitCastExprClass: { 1986 const Expr* SubExpr = cast<ImplicitCastExpr>(E)->getSubExpr(); 1987 1988 // Check for implicit promotion 1989 if (SubExpr->getType()->isFunctionType() || 1990 SubExpr->getType()->isArrayType()) 1991 return FindExpressionBaseAddressLValue(SubExpr); 1992 1993 // Check for pointer->pointer cast 1994 if (SubExpr->getType()->isPointerType()) 1995 return FindExpressionBaseAddress(SubExpr); 1996 1997 // We assume that we have an arithmetic expression here; 1998 // if we don't, we'll figure it out later 1999 return 0; 2000 } 2001 case Expr::CStyleCastExprClass: { 2002 const Expr* SubExpr = cast<CastExpr>(E)->getSubExpr(); 2003 2004 // Check for pointer->pointer cast 2005 if (SubExpr->getType()->isPointerType()) 2006 return FindExpressionBaseAddress(SubExpr); 2007 2008 // We assume that we have an arithmetic expression here; 2009 // if we don't, we'll figure it out later 2010 return 0; 2011 } 2012 } 2013} 2014 2015bool Sema::CheckArithmeticConstantExpression(const Expr* Init) { 2016 switch (Init->getStmtClass()) { 2017 default: 2018 InitializerElementNotConstant(Init); 2019 return true; 2020 case Expr::ParenExprClass: { 2021 const ParenExpr* PE = cast<ParenExpr>(Init); 2022 return CheckArithmeticConstantExpression(PE->getSubExpr()); 2023 } 2024 case Expr::FloatingLiteralClass: 2025 case Expr::IntegerLiteralClass: 2026 case Expr::CharacterLiteralClass: 2027 case Expr::ImaginaryLiteralClass: 2028 case Expr::TypesCompatibleExprClass: 2029 case Expr::CXXBoolLiteralExprClass: 2030 return false; 2031 case Expr::CallExprClass: 2032 case Expr::CXXOperatorCallExprClass: { 2033 const CallExpr *CE = cast<CallExpr>(Init); 2034 2035 // Allow any constant foldable calls to builtins. 2036 if (CE->isBuiltinCall() && CE->isEvaluatable(Context)) 2037 return false; 2038 2039 InitializerElementNotConstant(Init); 2040 return true; 2041 } 2042 case Expr::DeclRefExprClass: 2043 case Expr::QualifiedDeclRefExprClass: { 2044 const Decl *D = cast<DeclRefExpr>(Init)->getDecl(); 2045 if (isa<EnumConstantDecl>(D)) 2046 return false; 2047 InitializerElementNotConstant(Init); 2048 return true; 2049 } 2050 case Expr::CompoundLiteralExprClass: 2051 // Allow "(vector type){2,4}"; normal C constraints don't allow this, 2052 // but vectors are allowed to be magic. 2053 if (Init->getType()->isVectorType()) 2054 return false; 2055 InitializerElementNotConstant(Init); 2056 return true; 2057 case Expr::UnaryOperatorClass: { 2058 const UnaryOperator *Exp = cast<UnaryOperator>(Init); 2059 2060 switch (Exp->getOpcode()) { 2061 // Address, indirect, pre/post inc/dec, etc are not valid constant exprs. 2062 // See C99 6.6p3. 2063 default: 2064 InitializerElementNotConstant(Init); 2065 return true; 2066 case UnaryOperator::OffsetOf: 2067 if (Exp->getSubExpr()->getType()->isConstantSizeType()) 2068 return false; 2069 InitializerElementNotConstant(Init); 2070 return true; 2071 case UnaryOperator::Extension: 2072 case UnaryOperator::LNot: 2073 case UnaryOperator::Plus: 2074 case UnaryOperator::Minus: 2075 case UnaryOperator::Not: 2076 return CheckArithmeticConstantExpression(Exp->getSubExpr()); 2077 } 2078 } 2079 case Expr::SizeOfAlignOfExprClass: { 2080 const SizeOfAlignOfExpr *Exp = cast<SizeOfAlignOfExpr>(Init); 2081 // Special check for void types, which are allowed as an extension 2082 if (Exp->getTypeOfArgument()->isVoidType()) 2083 return false; 2084 // alignof always evaluates to a constant. 2085 // FIXME: is sizeof(int[3.0]) a constant expression? 2086 if (Exp->isSizeOf() && !Exp->getTypeOfArgument()->isConstantSizeType()) { 2087 InitializerElementNotConstant(Init); 2088 return true; 2089 } 2090 return false; 2091 } 2092 case Expr::BinaryOperatorClass: { 2093 const BinaryOperator *Exp = cast<BinaryOperator>(Init); 2094 2095 if (Exp->getLHS()->getType()->isArithmeticType() && 2096 Exp->getRHS()->getType()->isArithmeticType()) { 2097 return CheckArithmeticConstantExpression(Exp->getLHS()) || 2098 CheckArithmeticConstantExpression(Exp->getRHS()); 2099 } 2100 2101 if (Exp->getLHS()->getType()->isPointerType() && 2102 Exp->getRHS()->getType()->isPointerType()) { 2103 const Expr* LHSBase = FindExpressionBaseAddress(Exp->getLHS()); 2104 const Expr* RHSBase = FindExpressionBaseAddress(Exp->getRHS()); 2105 2106 // Only allow a null (constant integer) base; we could 2107 // allow some additional cases if necessary, but this 2108 // is sufficient to cover offsetof-like constructs. 2109 if (!LHSBase && !RHSBase) { 2110 return CheckAddressConstantExpression(Exp->getLHS()) || 2111 CheckAddressConstantExpression(Exp->getRHS()); 2112 } 2113 } 2114 2115 InitializerElementNotConstant(Init); 2116 return true; 2117 } 2118 case Expr::ImplicitCastExprClass: 2119 case Expr::CStyleCastExprClass: { 2120 const Expr *SubExpr = cast<CastExpr>(Init)->getSubExpr(); 2121 if (SubExpr->getType()->isArithmeticType()) 2122 return CheckArithmeticConstantExpression(SubExpr); 2123 2124 if (SubExpr->getType()->isPointerType()) { 2125 const Expr* Base = FindExpressionBaseAddress(SubExpr); 2126 // If the pointer has a null base, this is an offsetof-like construct 2127 if (!Base) 2128 return CheckAddressConstantExpression(SubExpr); 2129 } 2130 2131 InitializerElementNotConstant(Init); 2132 return true; 2133 } 2134 case Expr::ConditionalOperatorClass: { 2135 const ConditionalOperator *Exp = cast<ConditionalOperator>(Init); 2136 2137 // If GNU extensions are disabled, we require all operands to be arithmetic 2138 // constant expressions. 2139 if (getLangOptions().NoExtensions) { 2140 return CheckArithmeticConstantExpression(Exp->getCond()) || 2141 (Exp->getLHS() && CheckArithmeticConstantExpression(Exp->getLHS())) || 2142 CheckArithmeticConstantExpression(Exp->getRHS()); 2143 } 2144 2145 // Otherwise, we have to emulate some of the behavior of fold here. 2146 // Basically GCC treats things like "4 ? 1 : somefunc()" as a constant 2147 // because it can constant fold things away. To retain compatibility with 2148 // GCC code, we see if we can fold the condition to a constant (which we 2149 // should always be able to do in theory). If so, we only require the 2150 // specified arm of the conditional to be a constant. This is a horrible 2151 // hack, but is require by real world code that uses __builtin_constant_p. 2152 Expr::EvalResult EvalResult; 2153 if (!Exp->getCond()->Evaluate(EvalResult, Context) || 2154 EvalResult.HasSideEffects) { 2155 // If Evaluate couldn't fold it, CheckArithmeticConstantExpression 2156 // won't be able to either. Use it to emit the diagnostic though. 2157 bool Res = CheckArithmeticConstantExpression(Exp->getCond()); 2158 assert(Res && "Evaluate couldn't evaluate this constant?"); 2159 return Res; 2160 } 2161 2162 // Verify that the side following the condition is also a constant. 2163 const Expr *TrueSide = Exp->getLHS(), *FalseSide = Exp->getRHS(); 2164 if (EvalResult.Val.getInt() == 0) 2165 std::swap(TrueSide, FalseSide); 2166 2167 if (TrueSide && CheckArithmeticConstantExpression(TrueSide)) 2168 return true; 2169 2170 // Okay, the evaluated side evaluates to a constant, so we accept this. 2171 // Check to see if the other side is obviously not a constant. If so, 2172 // emit a warning that this is a GNU extension. 2173 if (FalseSide && !FalseSide->isEvaluatable(Context)) 2174 Diag(Init->getExprLoc(), 2175 diag::ext_typecheck_expression_not_constant_but_accepted) 2176 << FalseSide->getSourceRange(); 2177 return false; 2178 } 2179 } 2180} 2181 2182bool Sema::CheckForConstantInitializer(Expr *Init, QualType DclT) { 2183 Expr::EvalResult Result; 2184 2185 Init = Init->IgnoreParens(); 2186 2187 if (Init->Evaluate(Result, Context) && !Result.HasSideEffects) 2188 return false; 2189 2190 // Look through CXXDefaultArgExprs; they have no meaning in this context. 2191 if (CXXDefaultArgExpr* DAE = dyn_cast<CXXDefaultArgExpr>(Init)) 2192 return CheckForConstantInitializer(DAE->getExpr(), DclT); 2193 2194 if (CompoundLiteralExpr *e = dyn_cast<CompoundLiteralExpr>(Init)) 2195 return CheckForConstantInitializer(e->getInitializer(), DclT); 2196 2197 if (InitListExpr *Exp = dyn_cast<InitListExpr>(Init)) { 2198 unsigned numInits = Exp->getNumInits(); 2199 for (unsigned i = 0; i < numInits; i++) { 2200 // FIXME: Need to get the type of the declaration for C++, 2201 // because it could be a reference? 2202 if (CheckForConstantInitializer(Exp->getInit(i), 2203 Exp->getInit(i)->getType())) 2204 return true; 2205 } 2206 return false; 2207 } 2208 2209 // FIXME: We can probably remove some of this code below, now that 2210 // Expr::Evaluate is doing the heavy lifting for scalars. 2211 2212 if (Init->isNullPointerConstant(Context)) 2213 return false; 2214 if (Init->getType()->isArithmeticType()) { 2215 QualType InitTy = Context.getCanonicalType(Init->getType()) 2216 .getUnqualifiedType(); 2217 if (InitTy == Context.BoolTy) { 2218 // Special handling for pointers implicitly cast to bool; 2219 // (e.g. "_Bool rr = &rr;"). This is only legal at the top level. 2220 if (ImplicitCastExpr* ICE = dyn_cast<ImplicitCastExpr>(Init)) { 2221 Expr* SubE = ICE->getSubExpr(); 2222 if (SubE->getType()->isPointerType() || 2223 SubE->getType()->isArrayType() || 2224 SubE->getType()->isFunctionType()) { 2225 return CheckAddressConstantExpression(Init); 2226 } 2227 } 2228 } else if (InitTy->isIntegralType()) { 2229 Expr* SubE = 0; 2230 if (CastExpr* CE = dyn_cast<CastExpr>(Init)) 2231 SubE = CE->getSubExpr(); 2232 // Special check for pointer cast to int; we allow as an extension 2233 // an address constant cast to an integer if the integer 2234 // is of an appropriate width (this sort of code is apparently used 2235 // in some places). 2236 // FIXME: Add pedwarn? 2237 // FIXME: Don't allow bitfields here! Need the FieldDecl for that. 2238 if (SubE && (SubE->getType()->isPointerType() || 2239 SubE->getType()->isArrayType() || 2240 SubE->getType()->isFunctionType())) { 2241 unsigned IntWidth = Context.getTypeSize(Init->getType()); 2242 unsigned PointerWidth = Context.getTypeSize(Context.VoidPtrTy); 2243 if (IntWidth >= PointerWidth) 2244 return CheckAddressConstantExpression(Init); 2245 } 2246 } 2247 2248 return CheckArithmeticConstantExpression(Init); 2249 } 2250 2251 if (Init->getType()->isPointerType()) 2252 return CheckAddressConstantExpression(Init); 2253 2254 // An array type at the top level that isn't an init-list must 2255 // be a string literal 2256 if (Init->getType()->isArrayType()) 2257 return false; 2258 2259 if (Init->getType()->isFunctionType()) 2260 return false; 2261 2262 // Allow block exprs at top level. 2263 if (Init->getType()->isBlockPointerType()) 2264 return false; 2265 2266 // GCC cast to union extension 2267 // note: the validity of the cast expr is checked by CheckCastTypes() 2268 if (CastExpr *C = dyn_cast<CastExpr>(Init)) { 2269 QualType T = C->getType(); 2270 return T->isUnionType() && CheckForConstantInitializer(C->getSubExpr(), T); 2271 } 2272 2273 InitializerElementNotConstant(Init); 2274 return true; 2275} 2276 2277void Sema::AddInitializerToDecl(DeclTy *dcl, ExprArg init) { 2278 AddInitializerToDecl(dcl, move(init), /*DirectInit=*/false); 2279} 2280 2281/// AddInitializerToDecl - Adds the initializer Init to the 2282/// declaration dcl. If DirectInit is true, this is C++ direct 2283/// initialization rather than copy initialization. 2284void Sema::AddInitializerToDecl(DeclTy *dcl, ExprArg init, bool DirectInit) { 2285 Decl *RealDecl = static_cast<Decl *>(dcl); 2286 Expr *Init = static_cast<Expr *>(init.release()); 2287 assert(Init && "missing initializer"); 2288 2289 // If there is no declaration, there was an error parsing it. Just ignore 2290 // the initializer. 2291 if (RealDecl == 0) { 2292 delete Init; 2293 return; 2294 } 2295 2296 VarDecl *VDecl = dyn_cast<VarDecl>(RealDecl); 2297 if (!VDecl) { 2298 Diag(dyn_cast<ScopedDecl>(RealDecl)->getLocation(), 2299 diag::err_illegal_initializer); 2300 RealDecl->setInvalidDecl(); 2301 return; 2302 } 2303 // Get the decls type and save a reference for later, since 2304 // CheckInitializerTypes may change it. 2305 QualType DclT = VDecl->getType(), SavT = DclT; 2306 if (VDecl->isBlockVarDecl()) { 2307 VarDecl::StorageClass SC = VDecl->getStorageClass(); 2308 if (SC == VarDecl::Extern) { // C99 6.7.8p5 2309 Diag(VDecl->getLocation(), diag::err_block_extern_cant_init); 2310 VDecl->setInvalidDecl(); 2311 } else if (!VDecl->isInvalidDecl()) { 2312 if (CheckInitializerTypes(Init, DclT, VDecl->getLocation(), 2313 VDecl->getDeclName(), DirectInit)) 2314 VDecl->setInvalidDecl(); 2315 2316 // C++ 3.6.2p2, allow dynamic initialization of static initializers. 2317 if (!getLangOptions().CPlusPlus) { 2318 if (SC == VarDecl::Static) // C99 6.7.8p4. 2319 CheckForConstantInitializer(Init, DclT); 2320 } 2321 } 2322 } else if (VDecl->isFileVarDecl()) { 2323 if (VDecl->getStorageClass() == VarDecl::Extern) 2324 Diag(VDecl->getLocation(), diag::warn_extern_init); 2325 if (!VDecl->isInvalidDecl()) 2326 if (CheckInitializerTypes(Init, DclT, VDecl->getLocation(), 2327 VDecl->getDeclName(), DirectInit)) 2328 VDecl->setInvalidDecl(); 2329 2330 // C++ 3.6.2p2, allow dynamic initialization of static initializers. 2331 if (!getLangOptions().CPlusPlus) { 2332 // C99 6.7.8p4. All file scoped initializers need to be constant. 2333 CheckForConstantInitializer(Init, DclT); 2334 } 2335 } 2336 // If the type changed, it means we had an incomplete type that was 2337 // completed by the initializer. For example: 2338 // int ary[] = { 1, 3, 5 }; 2339 // "ary" transitions from a VariableArrayType to a ConstantArrayType. 2340 if (!VDecl->isInvalidDecl() && (DclT != SavT)) { 2341 VDecl->setType(DclT); 2342 Init->setType(DclT); 2343 } 2344 2345 // Attach the initializer to the decl. 2346 VDecl->setInit(Init); 2347 return; 2348} 2349 2350void Sema::ActOnUninitializedDecl(DeclTy *dcl) { 2351 Decl *RealDecl = static_cast<Decl *>(dcl); 2352 2353 // If there is no declaration, there was an error parsing it. Just ignore it. 2354 if (RealDecl == 0) 2355 return; 2356 2357 if (VarDecl *Var = dyn_cast<VarDecl>(RealDecl)) { 2358 QualType Type = Var->getType(); 2359 // C++ [dcl.init.ref]p3: 2360 // The initializer can be omitted for a reference only in a 2361 // parameter declaration (8.3.5), in the declaration of a 2362 // function return type, in the declaration of a class member 2363 // within its class declaration (9.2), and where the extern 2364 // specifier is explicitly used. 2365 if (Type->isReferenceType() && 2366 Var->getStorageClass() != VarDecl::Extern && 2367 Var->getStorageClass() != VarDecl::PrivateExtern) { 2368 Diag(Var->getLocation(), diag::err_reference_var_requires_init) 2369 << Var->getDeclName() 2370 << SourceRange(Var->getLocation(), Var->getLocation()); 2371 Var->setInvalidDecl(); 2372 return; 2373 } 2374 2375 // C++ [dcl.init]p9: 2376 // 2377 // If no initializer is specified for an object, and the object 2378 // is of (possibly cv-qualified) non-POD class type (or array 2379 // thereof), the object shall be default-initialized; if the 2380 // object is of const-qualified type, the underlying class type 2381 // shall have a user-declared default constructor. 2382 if (getLangOptions().CPlusPlus) { 2383 QualType InitType = Type; 2384 if (const ArrayType *Array = Context.getAsArrayType(Type)) 2385 InitType = Array->getElementType(); 2386 if (Var->getStorageClass() != VarDecl::Extern && 2387 Var->getStorageClass() != VarDecl::PrivateExtern && 2388 InitType->isRecordType()) { 2389 const CXXConstructorDecl *Constructor 2390 = PerformInitializationByConstructor(InitType, 0, 0, 2391 Var->getLocation(), 2392 SourceRange(Var->getLocation(), 2393 Var->getLocation()), 2394 Var->getDeclName(), 2395 IK_Default); 2396 if (!Constructor) 2397 Var->setInvalidDecl(); 2398 } 2399 } 2400 2401#if 0 2402 // FIXME: Temporarily disabled because we are not properly parsing 2403 // linkage specifications on declarations, e.g., 2404 // 2405 // extern "C" const CGPoint CGPointerZero; 2406 // 2407 // C++ [dcl.init]p9: 2408 // 2409 // If no initializer is specified for an object, and the 2410 // object is of (possibly cv-qualified) non-POD class type (or 2411 // array thereof), the object shall be default-initialized; if 2412 // the object is of const-qualified type, the underlying class 2413 // type shall have a user-declared default 2414 // constructor. Otherwise, if no initializer is specified for 2415 // an object, the object and its subobjects, if any, have an 2416 // indeterminate initial value; if the object or any of its 2417 // subobjects are of const-qualified type, the program is 2418 // ill-formed. 2419 // 2420 // This isn't technically an error in C, so we don't diagnose it. 2421 // 2422 // FIXME: Actually perform the POD/user-defined default 2423 // constructor check. 2424 if (getLangOptions().CPlusPlus && 2425 Context.getCanonicalType(Type).isConstQualified() && 2426 Var->getStorageClass() != VarDecl::Extern) 2427 Diag(Var->getLocation(), diag::err_const_var_requires_init) 2428 << Var->getName() 2429 << SourceRange(Var->getLocation(), Var->getLocation()); 2430#endif 2431 } 2432} 2433 2434/// The declarators are chained together backwards, reverse the list. 2435Sema::DeclTy *Sema::FinalizeDeclaratorGroup(Scope *S, DeclTy *group) { 2436 // Often we have single declarators, handle them quickly. 2437 Decl *GroupDecl = static_cast<Decl*>(group); 2438 if (GroupDecl == 0) 2439 return 0; 2440 2441 ScopedDecl *Group = dyn_cast<ScopedDecl>(GroupDecl); 2442 ScopedDecl *NewGroup = 0; 2443 if (Group->getNextDeclarator() == 0) 2444 NewGroup = Group; 2445 else { // reverse the list. 2446 while (Group) { 2447 ScopedDecl *Next = Group->getNextDeclarator(); 2448 Group->setNextDeclarator(NewGroup); 2449 NewGroup = Group; 2450 Group = Next; 2451 } 2452 } 2453 // Perform semantic analysis that depends on having fully processed both 2454 // the declarator and initializer. 2455 for (ScopedDecl *ID = NewGroup; ID; ID = ID->getNextDeclarator()) { 2456 VarDecl *IDecl = dyn_cast<VarDecl>(ID); 2457 if (!IDecl) 2458 continue; 2459 QualType T = IDecl->getType(); 2460 2461 if (T->isVariableArrayType()) { 2462 const VariableArrayType *VAT = Context.getAsVariableArrayType(T); 2463 2464 // FIXME: This won't give the correct result for 2465 // int a[10][n]; 2466 SourceRange SizeRange = VAT->getSizeExpr()->getSourceRange(); 2467 if (IDecl->isFileVarDecl()) { 2468 Diag(IDecl->getLocation(), diag::err_vla_decl_in_file_scope) << 2469 SizeRange; 2470 2471 IDecl->setInvalidDecl(); 2472 } else { 2473 // C99 6.7.5.2p2: If an identifier is declared to be an object with 2474 // static storage duration, it shall not have a variable length array. 2475 if (IDecl->getStorageClass() == VarDecl::Static) { 2476 Diag(IDecl->getLocation(), diag::err_vla_decl_has_static_storage) 2477 << SizeRange; 2478 IDecl->setInvalidDecl(); 2479 } else if (IDecl->getStorageClass() == VarDecl::Extern) { 2480 Diag(IDecl->getLocation(), diag::err_vla_decl_has_extern_linkage) 2481 << SizeRange; 2482 IDecl->setInvalidDecl(); 2483 } 2484 } 2485 } else if (T->isVariablyModifiedType()) { 2486 if (IDecl->isFileVarDecl()) { 2487 Diag(IDecl->getLocation(), diag::err_vm_decl_in_file_scope); 2488 IDecl->setInvalidDecl(); 2489 } else { 2490 if (IDecl->getStorageClass() == VarDecl::Extern) { 2491 Diag(IDecl->getLocation(), diag::err_vm_decl_has_extern_linkage); 2492 IDecl->setInvalidDecl(); 2493 } 2494 } 2495 } 2496 2497 // Block scope. C99 6.7p7: If an identifier for an object is declared with 2498 // no linkage (C99 6.2.2p6), the type for the object shall be complete... 2499 if (IDecl->isBlockVarDecl() && 2500 IDecl->getStorageClass() != VarDecl::Extern) { 2501 if (T->isIncompleteType() && !IDecl->isInvalidDecl()) { 2502 Diag(IDecl->getLocation(), diag::err_typecheck_decl_incomplete_type)<<T; 2503 IDecl->setInvalidDecl(); 2504 } 2505 } 2506 // File scope. C99 6.9.2p2: A declaration of an identifier for and 2507 // object that has file scope without an initializer, and without a 2508 // storage-class specifier or with the storage-class specifier "static", 2509 // constitutes a tentative definition. Note: A tentative definition with 2510 // external linkage is valid (C99 6.2.2p5). 2511 if (isTentativeDefinition(IDecl)) { 2512 if (T->isIncompleteArrayType()) { 2513 // C99 6.9.2 (p2, p5): Implicit initialization causes an incomplete 2514 // array to be completed. Don't issue a diagnostic. 2515 } else if (T->isIncompleteType() && !IDecl->isInvalidDecl()) { 2516 // C99 6.9.2p3: If the declaration of an identifier for an object is 2517 // a tentative definition and has internal linkage (C99 6.2.2p3), the 2518 // declared type shall not be an incomplete type. 2519 Diag(IDecl->getLocation(), diag::err_typecheck_decl_incomplete_type)<<T; 2520 IDecl->setInvalidDecl(); 2521 } 2522 } 2523 if (IDecl->isFileVarDecl()) 2524 CheckForFileScopedRedefinitions(S, IDecl); 2525 } 2526 return NewGroup; 2527} 2528 2529/// ActOnParamDeclarator - Called from Parser::ParseFunctionDeclarator() 2530/// to introduce parameters into function prototype scope. 2531Sema::DeclTy * 2532Sema::ActOnParamDeclarator(Scope *S, Declarator &D) { 2533 const DeclSpec &DS = D.getDeclSpec(); 2534 2535 // Verify C99 6.7.5.3p2: The only SCS allowed is 'register'. 2536 VarDecl::StorageClass StorageClass = VarDecl::None; 2537 if (DS.getStorageClassSpec() == DeclSpec::SCS_register) { 2538 StorageClass = VarDecl::Register; 2539 } else if (DS.getStorageClassSpec() != DeclSpec::SCS_unspecified) { 2540 Diag(DS.getStorageClassSpecLoc(), 2541 diag::err_invalid_storage_class_in_func_decl); 2542 D.getMutableDeclSpec().ClearStorageClassSpecs(); 2543 } 2544 if (DS.isThreadSpecified()) { 2545 Diag(DS.getThreadSpecLoc(), 2546 diag::err_invalid_storage_class_in_func_decl); 2547 D.getMutableDeclSpec().ClearStorageClassSpecs(); 2548 } 2549 2550 // Check that there are no default arguments inside the type of this 2551 // parameter (C++ only). 2552 if (getLangOptions().CPlusPlus) 2553 CheckExtraCXXDefaultArguments(D); 2554 2555 // In this context, we *do not* check D.getInvalidType(). If the declarator 2556 // type was invalid, GetTypeForDeclarator() still returns a "valid" type, 2557 // though it will not reflect the user specified type. 2558 QualType parmDeclType = GetTypeForDeclarator(D, S); 2559 2560 assert(!parmDeclType.isNull() && "GetTypeForDeclarator() returned null type"); 2561 2562 // TODO: CHECK FOR CONFLICTS, multiple decls with same name in one scope. 2563 // Can this happen for params? We already checked that they don't conflict 2564 // among each other. Here they can only shadow globals, which is ok. 2565 IdentifierInfo *II = D.getIdentifier(); 2566 if (Decl *PrevDecl = LookupDecl(II, Decl::IDNS_Ordinary, S)) { 2567 if (PrevDecl->isTemplateParameter()) { 2568 // Maybe we will complain about the shadowed template parameter. 2569 DiagnoseTemplateParameterShadow(D.getIdentifierLoc(), PrevDecl); 2570 // Just pretend that we didn't see the previous declaration. 2571 PrevDecl = 0; 2572 } else if (S->isDeclScope(PrevDecl)) { 2573 Diag(D.getIdentifierLoc(), diag::err_param_redefinition) << II; 2574 2575 // Recover by removing the name 2576 II = 0; 2577 D.SetIdentifier(0, D.getIdentifierLoc()); 2578 } 2579 } 2580 2581 // Perform the default function/array conversion (C99 6.7.5.3p[7,8]). 2582 // Doing the promotion here has a win and a loss. The win is the type for 2583 // both Decl's and DeclRefExpr's will match (a convenient invariant for the 2584 // code generator). The loss is the orginal type isn't preserved. For example: 2585 // 2586 // void func(int parmvardecl[5]) { // convert "int [5]" to "int *" 2587 // int blockvardecl[5]; 2588 // sizeof(parmvardecl); // size == 4 2589 // sizeof(blockvardecl); // size == 20 2590 // } 2591 // 2592 // For expressions, all implicit conversions are captured using the 2593 // ImplicitCastExpr AST node (we have no such mechanism for Decl's). 2594 // 2595 // FIXME: If a source translation tool needs to see the original type, then 2596 // we need to consider storing both types (in ParmVarDecl)... 2597 // 2598 if (parmDeclType->isArrayType()) { 2599 // int x[restrict 4] -> int *restrict 2600 parmDeclType = Context.getArrayDecayedType(parmDeclType); 2601 } else if (parmDeclType->isFunctionType()) 2602 parmDeclType = Context.getPointerType(parmDeclType); 2603 2604 ParmVarDecl *New = ParmVarDecl::Create(Context, CurContext, 2605 D.getIdentifierLoc(), II, 2606 parmDeclType, StorageClass, 2607 0, 0); 2608 2609 if (D.getInvalidType()) 2610 New->setInvalidDecl(); 2611 2612 // Parameter declarators cannot be qualified (C++ [dcl.meaning]p1). 2613 if (D.getCXXScopeSpec().isSet()) { 2614 Diag(D.getIdentifierLoc(), diag::err_qualified_param_declarator) 2615 << D.getCXXScopeSpec().getRange(); 2616 New->setInvalidDecl(); 2617 } 2618 2619 // Add the parameter declaration into this scope. 2620 S->AddDecl(New); 2621 if (II) 2622 IdResolver.AddDecl(New); 2623 2624 ProcessDeclAttributes(New, D); 2625 return New; 2626 2627} 2628 2629Sema::DeclTy *Sema::ActOnStartOfFunctionDef(Scope *FnBodyScope, Declarator &D) { 2630 assert(getCurFunctionDecl() == 0 && "Function parsing confused"); 2631 assert(D.getTypeObject(0).Kind == DeclaratorChunk::Function && 2632 "Not a function declarator!"); 2633 DeclaratorChunk::FunctionTypeInfo &FTI = D.getTypeObject(0).Fun; 2634 2635 // Verify 6.9.1p6: 'every identifier in the identifier list shall be declared' 2636 // for a K&R function. 2637 if (!FTI.hasPrototype) { 2638 for (unsigned i = 0, e = FTI.NumArgs; i != e; ++i) { 2639 if (FTI.ArgInfo[i].Param == 0) { 2640 Diag(FTI.ArgInfo[i].IdentLoc, diag::ext_param_not_declared) 2641 << FTI.ArgInfo[i].Ident; 2642 // Implicitly declare the argument as type 'int' for lack of a better 2643 // type. 2644 DeclSpec DS; 2645 const char* PrevSpec; // unused 2646 DS.SetTypeSpecType(DeclSpec::TST_int, FTI.ArgInfo[i].IdentLoc, 2647 PrevSpec); 2648 Declarator ParamD(DS, Declarator::KNRTypeListContext); 2649 ParamD.SetIdentifier(FTI.ArgInfo[i].Ident, FTI.ArgInfo[i].IdentLoc); 2650 FTI.ArgInfo[i].Param = ActOnParamDeclarator(FnBodyScope, ParamD); 2651 } 2652 } 2653 } else { 2654 // FIXME: Diagnose arguments without names in C. 2655 } 2656 2657 Scope *ParentScope = FnBodyScope->getParent(); 2658 2659 return ActOnStartOfFunctionDef(FnBodyScope, 2660 ActOnDeclarator(ParentScope, D, 0, 2661 /*IsFunctionDefinition=*/true)); 2662} 2663 2664Sema::DeclTy *Sema::ActOnStartOfFunctionDef(Scope *FnBodyScope, DeclTy *D) { 2665 Decl *decl = static_cast<Decl*>(D); 2666 FunctionDecl *FD = cast<FunctionDecl>(decl); 2667 2668 // See if this is a redefinition. 2669 const FunctionDecl *Definition; 2670 if (FD->getBody(Definition)) { 2671 Diag(FD->getLocation(), diag::err_redefinition) << FD->getDeclName(); 2672 Diag(Definition->getLocation(), diag::note_previous_definition); 2673 } 2674 2675 PushDeclContext(FnBodyScope, FD); 2676 2677 // Check the validity of our function parameters 2678 CheckParmsForFunctionDef(FD); 2679 2680 // Introduce our parameters into the function scope 2681 for (unsigned p = 0, NumParams = FD->getNumParams(); p < NumParams; ++p) { 2682 ParmVarDecl *Param = FD->getParamDecl(p); 2683 Param->setOwningFunction(FD); 2684 2685 // If this has an identifier, add it to the scope stack. 2686 if (Param->getIdentifier()) 2687 PushOnScopeChains(Param, FnBodyScope); 2688 } 2689 2690 // Checking attributes of current function definition 2691 // dllimport attribute. 2692 if (FD->getAttr<DLLImportAttr>() && (!FD->getAttr<DLLExportAttr>())) { 2693 // dllimport attribute cannot be applied to definition. 2694 if (!(FD->getAttr<DLLImportAttr>())->isInherited()) { 2695 Diag(FD->getLocation(), 2696 diag::err_attribute_can_be_applied_only_to_symbol_declaration) 2697 << "dllimport"; 2698 FD->setInvalidDecl(); 2699 return FD; 2700 } else { 2701 // If a symbol previously declared dllimport is later defined, the 2702 // attribute is ignored in subsequent references, and a warning is 2703 // emitted. 2704 Diag(FD->getLocation(), 2705 diag::warn_redeclaration_without_attribute_prev_attribute_ignored) 2706 << FD->getNameAsCString() << "dllimport"; 2707 } 2708 } 2709 return FD; 2710} 2711 2712Sema::DeclTy *Sema::ActOnFinishFunctionBody(DeclTy *D, StmtArg BodyArg) { 2713 Decl *dcl = static_cast<Decl *>(D); 2714 Stmt *Body = static_cast<Stmt*>(BodyArg.release()); 2715 if (FunctionDecl *FD = dyn_cast_or_null<FunctionDecl>(dcl)) { 2716 FD->setBody(Body); 2717 assert(FD == getCurFunctionDecl() && "Function parsing confused"); 2718 } else if (ObjCMethodDecl *MD = dyn_cast_or_null<ObjCMethodDecl>(dcl)) { 2719 MD->setBody((Stmt*)Body); 2720 } else 2721 return 0; 2722 PopDeclContext(); 2723 // Verify and clean out per-function state. 2724 2725 // Check goto/label use. 2726 for (llvm::DenseMap<IdentifierInfo*, LabelStmt*>::iterator 2727 I = LabelMap.begin(), E = LabelMap.end(); I != E; ++I) { 2728 // Verify that we have no forward references left. If so, there was a goto 2729 // or address of a label taken, but no definition of it. Label fwd 2730 // definitions are indicated with a null substmt. 2731 if (I->second->getSubStmt() == 0) { 2732 LabelStmt *L = I->second; 2733 // Emit error. 2734 Diag(L->getIdentLoc(), diag::err_undeclared_label_use) << L->getName(); 2735 2736 // At this point, we have gotos that use the bogus label. Stitch it into 2737 // the function body so that they aren't leaked and that the AST is well 2738 // formed. 2739 if (Body) { 2740 L->setSubStmt(new NullStmt(L->getIdentLoc())); 2741 cast<CompoundStmt>(Body)->push_back(L); 2742 } else { 2743 // The whole function wasn't parsed correctly, just delete this. 2744 delete L; 2745 } 2746 } 2747 } 2748 LabelMap.clear(); 2749 2750 return D; 2751} 2752 2753/// ImplicitlyDefineFunction - An undeclared identifier was used in a function 2754/// call, forming a call to an implicitly defined function (per C99 6.5.1p2). 2755ScopedDecl *Sema::ImplicitlyDefineFunction(SourceLocation Loc, 2756 IdentifierInfo &II, Scope *S) { 2757 // Extension in C99. Legal in C90, but warn about it. 2758 if (getLangOptions().C99) 2759 Diag(Loc, diag::ext_implicit_function_decl) << &II; 2760 else 2761 Diag(Loc, diag::warn_implicit_function_decl) << &II; 2762 2763 // FIXME: handle stuff like: 2764 // void foo() { extern float X(); } 2765 // void bar() { X(); } <-- implicit decl for X in another scope. 2766 2767 // Set a Declarator for the implicit definition: int foo(); 2768 const char *Dummy; 2769 DeclSpec DS; 2770 bool Error = DS.SetTypeSpecType(DeclSpec::TST_int, Loc, Dummy); 2771 Error = Error; // Silence warning. 2772 assert(!Error && "Error setting up implicit decl!"); 2773 Declarator D(DS, Declarator::BlockContext); 2774 D.AddTypeInfo(DeclaratorChunk::getFunction(false, false, 0, 0, 0, Loc)); 2775 D.SetIdentifier(&II, Loc); 2776 2777 // Insert this function into translation-unit scope. 2778 2779 DeclContext *PrevDC = CurContext; 2780 CurContext = Context.getTranslationUnitDecl(); 2781 2782 FunctionDecl *FD = 2783 dyn_cast<FunctionDecl>(static_cast<Decl*>(ActOnDeclarator(TUScope, D, 0))); 2784 FD->setImplicit(); 2785 2786 CurContext = PrevDC; 2787 2788 return FD; 2789} 2790 2791 2792TypedefDecl *Sema::ParseTypedefDecl(Scope *S, Declarator &D, QualType T, 2793 ScopedDecl *LastDeclarator) { 2794 assert(D.getIdentifier() && "Wrong callback for declspec without declarator"); 2795 assert(!T.isNull() && "GetTypeForDeclarator() returned null type"); 2796 2797 // Scope manipulation handled by caller. 2798 TypedefDecl *NewTD = TypedefDecl::Create(Context, CurContext, 2799 D.getIdentifierLoc(), 2800 D.getIdentifier(), 2801 T, LastDeclarator); 2802 if (D.getInvalidType()) 2803 NewTD->setInvalidDecl(); 2804 return NewTD; 2805} 2806 2807/// ActOnTag - This is invoked when we see 'struct foo' or 'struct {'. In the 2808/// former case, Name will be non-null. In the later case, Name will be null. 2809/// TagType indicates what kind of tag this is. TK indicates whether this is a 2810/// reference/declaration/definition of a tag. 2811Sema::DeclTy *Sema::ActOnTag(Scope *S, unsigned TagType, TagKind TK, 2812 SourceLocation KWLoc, const CXXScopeSpec &SS, 2813 IdentifierInfo *Name, SourceLocation NameLoc, 2814 AttributeList *Attr, 2815 MultiTemplateParamsArg TemplateParameterLists) { 2816 // If this is not a definition, it must have a name. 2817 assert((Name != 0 || TK == TK_Definition) && 2818 "Nameless record must be a definition!"); 2819 2820 TagDecl::TagKind Kind; 2821 switch (TagType) { 2822 default: assert(0 && "Unknown tag type!"); 2823 case DeclSpec::TST_struct: Kind = TagDecl::TK_struct; break; 2824 case DeclSpec::TST_union: Kind = TagDecl::TK_union; break; 2825 case DeclSpec::TST_class: Kind = TagDecl::TK_class; break; 2826 case DeclSpec::TST_enum: Kind = TagDecl::TK_enum; break; 2827 } 2828 2829 DeclContext *SearchDC = CurContext; 2830 DeclContext *DC = CurContext; 2831 DeclContext *LexicalContext = CurContext; 2832 ScopedDecl *PrevDecl = 0; 2833 2834 if (Name && SS.isNotEmpty()) { 2835 // We have a nested-name tag ('struct foo::bar'). 2836 2837 // Check for invalid 'foo::'. 2838 if (SS.isInvalid()) { 2839 Name = 0; 2840 goto CreateNewDecl; 2841 } 2842 2843 DC = static_cast<DeclContext*>(SS.getScopeRep()); 2844 // Look-up name inside 'foo::'. 2845 PrevDecl = dyn_cast_or_null<TagDecl>(LookupDecl(Name, Decl::IDNS_Tag,S,DC) 2846 .getAsDecl()); 2847 2848 // A tag 'foo::bar' must already exist. 2849 if (PrevDecl == 0) { 2850 Diag(NameLoc, diag::err_not_tag_in_scope) << Name << SS.getRange(); 2851 Name = 0; 2852 goto CreateNewDecl; 2853 } 2854 } else { 2855 // If this is a named struct, check to see if there was a previous forward 2856 // declaration or definition. 2857 // Use ScopedDecl instead of TagDecl, because a NamespaceDecl may come up. 2858 PrevDecl = dyn_cast_or_null<ScopedDecl>(LookupDecl(Name, Decl::IDNS_Tag,S) 2859 .getAsDecl()); 2860 2861 if (!getLangOptions().CPlusPlus && TK != TK_Reference) { 2862 // FIXME: This makes sure that we ignore the contexts associated 2863 // with C structs, unions, and enums when looking for a matching 2864 // tag declaration or definition. See the similar lookup tweak 2865 // in Sema::LookupDecl; is there a better way to deal with this? 2866 while (isa<RecordDecl>(SearchDC) || isa<EnumDecl>(SearchDC)) 2867 SearchDC = SearchDC->getParent(); 2868 } 2869 } 2870 2871 if (PrevDecl && PrevDecl->isTemplateParameter()) { 2872 // Maybe we will complain about the shadowed template parameter. 2873 DiagnoseTemplateParameterShadow(NameLoc, PrevDecl); 2874 // Just pretend that we didn't see the previous declaration. 2875 PrevDecl = 0; 2876 } 2877 2878 if (PrevDecl) { 2879 assert((isa<TagDecl>(PrevDecl) || isa<NamespaceDecl>(PrevDecl)) && 2880 "unexpected Decl type"); 2881 if (TagDecl *PrevTagDecl = dyn_cast<TagDecl>(PrevDecl)) { 2882 // If this is a use of a previous tag, or if the tag is already declared 2883 // in the same scope (so that the definition/declaration completes or 2884 // rementions the tag), reuse the decl. 2885 if (TK == TK_Reference || isDeclInScope(PrevDecl, SearchDC, S)) { 2886 // Make sure that this wasn't declared as an enum and now used as a 2887 // struct or something similar. 2888 if (PrevTagDecl->getTagKind() != Kind) { 2889 Diag(KWLoc, diag::err_use_with_wrong_tag) << Name; 2890 Diag(PrevDecl->getLocation(), diag::note_previous_use); 2891 // Recover by making this an anonymous redefinition. 2892 Name = 0; 2893 PrevDecl = 0; 2894 } else { 2895 // If this is a use, just return the declaration we found. 2896 2897 // FIXME: In the future, return a variant or some other clue 2898 // for the consumer of this Decl to know it doesn't own it. 2899 // For our current ASTs this shouldn't be a problem, but will 2900 // need to be changed with DeclGroups. 2901 if (TK == TK_Reference) 2902 return PrevDecl; 2903 2904 // Diagnose attempts to redefine a tag. 2905 if (TK == TK_Definition) { 2906 if (TagDecl *Def = PrevTagDecl->getDefinition(Context)) { 2907 Diag(NameLoc, diag::err_redefinition) << Name; 2908 Diag(Def->getLocation(), diag::note_previous_definition); 2909 // If this is a redefinition, recover by making this struct be 2910 // anonymous, which will make any later references get the previous 2911 // definition. 2912 Name = 0; 2913 PrevDecl = 0; 2914 } 2915 // Okay, this is definition of a previously declared or referenced 2916 // tag PrevDecl. We're going to create a new Decl for it. 2917 } 2918 } 2919 // If we get here we have (another) forward declaration or we 2920 // have a definition. Just create a new decl. 2921 } else { 2922 // If we get here, this is a definition of a new tag type in a nested 2923 // scope, e.g. "struct foo; void bar() { struct foo; }", just create a 2924 // new decl/type. We set PrevDecl to NULL so that the entities 2925 // have distinct types. 2926 PrevDecl = 0; 2927 } 2928 // If we get here, we're going to create a new Decl. If PrevDecl 2929 // is non-NULL, it's a definition of the tag declared by 2930 // PrevDecl. If it's NULL, we have a new definition. 2931 } else { 2932 // PrevDecl is a namespace. 2933 if (isDeclInScope(PrevDecl, SearchDC, S)) { 2934 // The tag name clashes with a namespace name, issue an error and 2935 // recover by making this tag be anonymous. 2936 Diag(NameLoc, diag::err_redefinition_different_kind) << Name; 2937 Diag(PrevDecl->getLocation(), diag::note_previous_definition); 2938 Name = 0; 2939 PrevDecl = 0; 2940 } else { 2941 // The existing declaration isn't relevant to us; we're in a 2942 // new scope, so clear out the previous declaration. 2943 PrevDecl = 0; 2944 } 2945 } 2946 } else if (TK == TK_Reference && SS.isEmpty() && Name && 2947 (Kind != TagDecl::TK_enum)) { 2948 // C++ [basic.scope.pdecl]p5: 2949 // -- for an elaborated-type-specifier of the form 2950 // 2951 // class-key identifier 2952 // 2953 // if the elaborated-type-specifier is used in the 2954 // decl-specifier-seq or parameter-declaration-clause of a 2955 // function defined in namespace scope, the identifier is 2956 // declared as a class-name in the namespace that contains 2957 // the declaration; otherwise, except as a friend 2958 // declaration, the identifier is declared in the smallest 2959 // non-class, non-function-prototype scope that contains the 2960 // declaration. 2961 // 2962 // C99 6.7.2.3p8 has a similar (but not identical!) provision for 2963 // C structs and unions. 2964 2965 // Find the context where we'll be declaring the tag. 2966 // FIXME: We would like to maintain the current DeclContext as the 2967 // lexical context, 2968 while (DC->isRecord()) 2969 DC = DC->getParent(); 2970 LexicalContext = DC; 2971 2972 // Find the scope where we'll be declaring the tag. 2973 while (S->isClassScope() || 2974 (getLangOptions().CPlusPlus && S->isFunctionPrototypeScope()) || 2975 ((S->getFlags() & Scope::DeclScope) == 0) || 2976 (S->getEntity() && 2977 ((DeclContext *)S->getEntity())->isTransparentContext())) 2978 S = S->getParent(); 2979 } 2980 2981CreateNewDecl: 2982 2983 // If there is an identifier, use the location of the identifier as the 2984 // location of the decl, otherwise use the location of the struct/union 2985 // keyword. 2986 SourceLocation Loc = NameLoc.isValid() ? NameLoc : KWLoc; 2987 2988 // Otherwise, create a new declaration. If there is a previous 2989 // declaration of the same entity, the two will be linked via 2990 // PrevDecl. 2991 TagDecl *New; 2992 2993 if (Kind == TagDecl::TK_enum) { 2994 // FIXME: Tag decls should be chained to any simultaneous vardecls, e.g.: 2995 // enum X { A, B, C } D; D should chain to X. 2996 New = EnumDecl::Create(Context, DC, Loc, Name, 2997 cast_or_null<EnumDecl>(PrevDecl)); 2998 // If this is an undefined enum, warn. 2999 if (TK != TK_Definition) Diag(Loc, diag::ext_forward_ref_enum); 3000 } else { 3001 // struct/union/class 3002 3003 // FIXME: Tag decls should be chained to any simultaneous vardecls, e.g.: 3004 // struct X { int A; } D; D should chain to X. 3005 if (getLangOptions().CPlusPlus) 3006 // FIXME: Look for a way to use RecordDecl for simple structs. 3007 New = CXXRecordDecl::Create(Context, Kind, DC, Loc, Name, 3008 cast_or_null<CXXRecordDecl>(PrevDecl)); 3009 else 3010 New = RecordDecl::Create(Context, Kind, DC, Loc, Name, 3011 cast_or_null<RecordDecl>(PrevDecl)); 3012 } 3013 3014 if (Kind != TagDecl::TK_enum) { 3015 // Handle #pragma pack: if the #pragma pack stack has non-default 3016 // alignment, make up a packed attribute for this decl. These 3017 // attributes are checked when the ASTContext lays out the 3018 // structure. 3019 // 3020 // It is important for implementing the correct semantics that this 3021 // happen here (in act on tag decl). The #pragma pack stack is 3022 // maintained as a result of parser callbacks which can occur at 3023 // many points during the parsing of a struct declaration (because 3024 // the #pragma tokens are effectively skipped over during the 3025 // parsing of the struct). 3026 if (unsigned Alignment = PackContext.getAlignment()) 3027 New->addAttr(new PackedAttr(Alignment * 8)); 3028 } 3029 3030 if (Attr) 3031 ProcessDeclAttributeList(New, Attr); 3032 3033 // If we're declaring or defining 3034 if (Name && S->isFunctionPrototypeScope() && !getLangOptions().CPlusPlus) 3035 Diag(Loc, diag::warn_decl_in_param_list) << Context.getTagDeclType(New); 3036 3037 // Set the lexical context. If the tag has a C++ scope specifier, the 3038 // lexical context will be different from the semantic context. 3039 New->setLexicalDeclContext(LexicalContext); 3040 3041 // If this has an identifier, add it to the scope stack. 3042 if (Name) { 3043 S = getNonFieldDeclScope(S); 3044 3045 // Add it to the decl chain. 3046 if (LexicalContext != CurContext) { 3047 // FIXME: PushOnScopeChains should not rely on CurContext! 3048 DeclContext *OldContext = CurContext; 3049 CurContext = LexicalContext; 3050 PushOnScopeChains(New, S); 3051 CurContext = OldContext; 3052 } else 3053 PushOnScopeChains(New, S); 3054 } else { 3055 LexicalContext->addDecl(New); 3056 } 3057 3058 return New; 3059} 3060 3061void Sema::ActOnTagStartDefinition(Scope *S, DeclTy *TagD) { 3062 TagDecl *Tag = cast<TagDecl>((Decl *)TagD); 3063 3064 // Enter the tag context. 3065 PushDeclContext(S, Tag); 3066 3067 if (CXXRecordDecl *Record = dyn_cast<CXXRecordDecl>(Tag)) { 3068 FieldCollector->StartClass(); 3069 3070 if (Record->getIdentifier()) { 3071 // C++ [class]p2: 3072 // [...] The class-name is also inserted into the scope of the 3073 // class itself; this is known as the injected-class-name. For 3074 // purposes of access checking, the injected-class-name is treated 3075 // as if it were a public member name. 3076 RecordDecl *InjectedClassName 3077 = CXXRecordDecl::Create(Context, Record->getTagKind(), 3078 CurContext, Record->getLocation(), 3079 Record->getIdentifier(), Record); 3080 InjectedClassName->setImplicit(); 3081 PushOnScopeChains(InjectedClassName, S); 3082 } 3083 } 3084} 3085 3086void Sema::ActOnTagFinishDefinition(Scope *S, DeclTy *TagD) { 3087 TagDecl *Tag = cast<TagDecl>((Decl *)TagD); 3088 3089 if (isa<CXXRecordDecl>(Tag)) 3090 FieldCollector->FinishClass(); 3091 3092 // Exit this scope of this tag's definition. 3093 PopDeclContext(); 3094 3095 // Notify the consumer that we've defined a tag. 3096 Consumer.HandleTagDeclDefinition(Tag); 3097} 3098 3099/// TryToFixInvalidVariablyModifiedType - Helper method to turn variable array 3100/// types into constant array types in certain situations which would otherwise 3101/// be errors (for GCC compatibility). 3102static QualType TryToFixInvalidVariablyModifiedType(QualType T, 3103 ASTContext &Context) { 3104 // This method tries to turn a variable array into a constant 3105 // array even when the size isn't an ICE. This is necessary 3106 // for compatibility with code that depends on gcc's buggy 3107 // constant expression folding, like struct {char x[(int)(char*)2];} 3108 const VariableArrayType* VLATy = dyn_cast<VariableArrayType>(T); 3109 if (!VLATy) return QualType(); 3110 3111 Expr::EvalResult EvalResult; 3112 if (!VLATy->getSizeExpr() || 3113 !VLATy->getSizeExpr()->Evaluate(EvalResult, Context)) 3114 return QualType(); 3115 3116 assert(EvalResult.Val.isInt() && "Size expressions must be integers!"); 3117 llvm::APSInt &Res = EvalResult.Val.getInt(); 3118 if (Res > llvm::APSInt(Res.getBitWidth(), Res.isUnsigned())) 3119 return Context.getConstantArrayType(VLATy->getElementType(), 3120 Res, ArrayType::Normal, 0); 3121 return QualType(); 3122} 3123 3124bool Sema::VerifyBitField(SourceLocation FieldLoc, IdentifierInfo *FieldName, 3125 QualType FieldTy, const Expr *BitWidth) { 3126 // FIXME: 6.7.2.1p4 - verify the field type. 3127 3128 llvm::APSInt Value; 3129 if (VerifyIntegerConstantExpression(BitWidth, &Value)) 3130 return true; 3131 3132 // Zero-width bitfield is ok for anonymous field. 3133 if (Value == 0 && FieldName) 3134 return Diag(FieldLoc, diag::err_bitfield_has_zero_width) << FieldName; 3135 3136 if (Value.isNegative()) 3137 return Diag(FieldLoc, diag::err_bitfield_has_negative_width) << FieldName; 3138 3139 uint64_t TypeSize = Context.getTypeSize(FieldTy); 3140 // FIXME: We won't need the 0 size once we check that the field type is valid. 3141 if (TypeSize && Value.getZExtValue() > TypeSize) 3142 return Diag(FieldLoc, diag::err_bitfield_width_exceeds_type_size) 3143 << FieldName << (unsigned)TypeSize; 3144 3145 return false; 3146} 3147 3148/// ActOnField - Each field of a struct/union/class is passed into this in order 3149/// to create a FieldDecl object for it. 3150Sema::DeclTy *Sema::ActOnField(Scope *S, DeclTy *TagD, 3151 SourceLocation DeclStart, 3152 Declarator &D, ExprTy *BitfieldWidth) { 3153 IdentifierInfo *II = D.getIdentifier(); 3154 Expr *BitWidth = (Expr*)BitfieldWidth; 3155 SourceLocation Loc = DeclStart; 3156 RecordDecl *Record = (RecordDecl *)TagD; 3157 if (II) Loc = D.getIdentifierLoc(); 3158 3159 // FIXME: Unnamed fields can be handled in various different ways, for 3160 // example, unnamed unions inject all members into the struct namespace! 3161 3162 QualType T = GetTypeForDeclarator(D, S); 3163 assert(!T.isNull() && "GetTypeForDeclarator() returned null type"); 3164 bool InvalidDecl = false; 3165 3166 // C99 6.7.2.1p8: A member of a structure or union may have any type other 3167 // than a variably modified type. 3168 if (T->isVariablyModifiedType()) { 3169 QualType FixedTy = TryToFixInvalidVariablyModifiedType(T, Context); 3170 if (!FixedTy.isNull()) { 3171 Diag(Loc, diag::warn_illegal_constant_array_size); 3172 T = FixedTy; 3173 } else { 3174 Diag(Loc, diag::err_typecheck_field_variable_size); 3175 T = Context.IntTy; 3176 InvalidDecl = true; 3177 } 3178 } 3179 3180 if (BitWidth) { 3181 if (VerifyBitField(Loc, II, T, BitWidth)) 3182 InvalidDecl = true; 3183 } else { 3184 // Not a bitfield. 3185 3186 // validate II. 3187 3188 } 3189 3190 // FIXME: Chain fielddecls together. 3191 FieldDecl *NewFD; 3192 3193 NewFD = FieldDecl::Create(Context, Record, 3194 Loc, II, T, BitWidth, 3195 D.getDeclSpec().getStorageClassSpec() == 3196 DeclSpec::SCS_mutable, 3197 /*PrevDecl=*/0); 3198 3199 if (II) { 3200 Decl *PrevDecl 3201 = LookupDecl(II, Decl::IDNS_Member, S, 0, false, false, false); 3202 if (PrevDecl && isDeclInScope(PrevDecl, CurContext, S) 3203 && !isa<TagDecl>(PrevDecl)) { 3204 Diag(Loc, diag::err_duplicate_member) << II; 3205 Diag(PrevDecl->getLocation(), diag::note_previous_declaration); 3206 NewFD->setInvalidDecl(); 3207 Record->setInvalidDecl(); 3208 } 3209 } 3210 3211 if (getLangOptions().CPlusPlus) { 3212 CheckExtraCXXDefaultArguments(D); 3213 if (!T->isPODType()) 3214 cast<CXXRecordDecl>(Record)->setPOD(false); 3215 } 3216 3217 ProcessDeclAttributes(NewFD, D); 3218 3219 if (D.getInvalidType() || InvalidDecl) 3220 NewFD->setInvalidDecl(); 3221 3222 if (II) { 3223 PushOnScopeChains(NewFD, S); 3224 } else 3225 Record->addDecl(NewFD); 3226 3227 return NewFD; 3228} 3229 3230/// TranslateIvarVisibility - Translate visibility from a token ID to an 3231/// AST enum value. 3232static ObjCIvarDecl::AccessControl 3233TranslateIvarVisibility(tok::ObjCKeywordKind ivarVisibility) { 3234 switch (ivarVisibility) { 3235 default: assert(0 && "Unknown visitibility kind"); 3236 case tok::objc_private: return ObjCIvarDecl::Private; 3237 case tok::objc_public: return ObjCIvarDecl::Public; 3238 case tok::objc_protected: return ObjCIvarDecl::Protected; 3239 case tok::objc_package: return ObjCIvarDecl::Package; 3240 } 3241} 3242 3243/// ActOnIvar - Each ivar field of an objective-c class is passed into this 3244/// in order to create an IvarDecl object for it. 3245Sema::DeclTy *Sema::ActOnIvar(Scope *S, 3246 SourceLocation DeclStart, 3247 Declarator &D, ExprTy *BitfieldWidth, 3248 tok::ObjCKeywordKind Visibility) { 3249 3250 IdentifierInfo *II = D.getIdentifier(); 3251 Expr *BitWidth = (Expr*)BitfieldWidth; 3252 SourceLocation Loc = DeclStart; 3253 if (II) Loc = D.getIdentifierLoc(); 3254 3255 // FIXME: Unnamed fields can be handled in various different ways, for 3256 // example, unnamed unions inject all members into the struct namespace! 3257 3258 QualType T = GetTypeForDeclarator(D, S); 3259 assert(!T.isNull() && "GetTypeForDeclarator() returned null type"); 3260 bool InvalidDecl = false; 3261 3262 if (BitWidth) { 3263 // TODO: Validate. 3264 //printf("WARNING: BITFIELDS IGNORED!\n"); 3265 3266 // 6.7.2.1p3 3267 // 6.7.2.1p4 3268 3269 } else { 3270 // Not a bitfield. 3271 3272 // validate II. 3273 3274 } 3275 3276 // C99 6.7.2.1p8: A member of a structure or union may have any type other 3277 // than a variably modified type. 3278 if (T->isVariablyModifiedType()) { 3279 Diag(Loc, diag::err_typecheck_ivar_variable_size); 3280 InvalidDecl = true; 3281 } 3282 3283 // Get the visibility (access control) for this ivar. 3284 ObjCIvarDecl::AccessControl ac = 3285 Visibility != tok::objc_not_keyword ? TranslateIvarVisibility(Visibility) 3286 : ObjCIvarDecl::None; 3287 3288 // Construct the decl. 3289 ObjCIvarDecl *NewID = ObjCIvarDecl::Create(Context, Loc, II, T, ac, 3290 (Expr *)BitfieldWidth); 3291 3292 if (II) { 3293 Decl *PrevDecl 3294 = LookupDecl(II, Decl::IDNS_Member, S, 0, false, false, false); 3295 if (PrevDecl && isDeclInScope(PrevDecl, CurContext, S) 3296 && !isa<TagDecl>(PrevDecl)) { 3297 Diag(Loc, diag::err_duplicate_member) << II; 3298 Diag(PrevDecl->getLocation(), diag::note_previous_declaration); 3299 NewID->setInvalidDecl(); 3300 } 3301 } 3302 3303 // Process attributes attached to the ivar. 3304 ProcessDeclAttributes(NewID, D); 3305 3306 if (D.getInvalidType() || InvalidDecl) 3307 NewID->setInvalidDecl(); 3308 3309 if (II) { 3310 // FIXME: When interfaces are DeclContexts, we'll need to add 3311 // these to the interface. 3312 S->AddDecl(NewID); 3313 IdResolver.AddDecl(NewID); 3314 } 3315 3316 return NewID; 3317} 3318 3319void Sema::ActOnFields(Scope* S, 3320 SourceLocation RecLoc, DeclTy *RecDecl, 3321 DeclTy **Fields, unsigned NumFields, 3322 SourceLocation LBrac, SourceLocation RBrac, 3323 AttributeList *Attr) { 3324 Decl *EnclosingDecl = static_cast<Decl*>(RecDecl); 3325 assert(EnclosingDecl && "missing record or interface decl"); 3326 RecordDecl *Record = dyn_cast<RecordDecl>(EnclosingDecl); 3327 3328 if (Record) { 3329 QualType RecordType = Context.getTypeDeclType(Record); 3330 if (RecordType->getAsRecordType()->getDecl()->isDefinition()) { 3331 RecordDecl *Def = RecordType->getAsRecordType()->getDecl(); 3332 // Diagnose code like: 3333 // struct S { struct S {} X; }; 3334 // We discover this when we complete the outer S. Reject and ignore the 3335 // outer S. 3336 Diag(Def->getLocation(), diag::err_nested_redefinition) 3337 << Def->getDeclName(); 3338 Diag(RecLoc, diag::note_previous_definition); 3339 Record->setInvalidDecl(); 3340 return; 3341 } 3342 } 3343 3344 // Verify that all the fields are okay. 3345 unsigned NumNamedMembers = 0; 3346 llvm::SmallVector<FieldDecl*, 32> RecFields; 3347 3348 for (unsigned i = 0; i != NumFields; ++i) { 3349 FieldDecl *FD = cast_or_null<FieldDecl>(static_cast<Decl*>(Fields[i])); 3350 assert(FD && "missing field decl"); 3351 3352 // Get the type for the field. 3353 Type *FDTy = FD->getType().getTypePtr(); 3354 3355 if (!FD->isAnonymousStructOrUnion()) { 3356 // Remember all fields written by the user. 3357 RecFields.push_back(FD); 3358 } 3359 3360 // C99 6.7.2.1p2 - A field may not be a function type. 3361 if (FDTy->isFunctionType()) { 3362 Diag(FD->getLocation(), diag::err_field_declared_as_function) 3363 << FD->getDeclName(); 3364 FD->setInvalidDecl(); 3365 EnclosingDecl->setInvalidDecl(); 3366 continue; 3367 } 3368 // C99 6.7.2.1p2 - A field may not be an incomplete type except... 3369 if (FDTy->isIncompleteType()) { 3370 if (!Record) { // Incomplete ivar type is always an error. 3371 Diag(FD->getLocation(), diag::err_field_incomplete) <<FD->getDeclName(); 3372 FD->setInvalidDecl(); 3373 EnclosingDecl->setInvalidDecl(); 3374 continue; 3375 } 3376 if (i != NumFields-1 || // ... that the last member ... 3377 !Record->isStruct() || // ... of a structure ... 3378 !FDTy->isArrayType()) { //... may have incomplete array type. 3379 Diag(FD->getLocation(), diag::err_field_incomplete) <<FD->getDeclName(); 3380 FD->setInvalidDecl(); 3381 EnclosingDecl->setInvalidDecl(); 3382 continue; 3383 } 3384 if (NumNamedMembers < 1) { //... must have more than named member ... 3385 Diag(FD->getLocation(), diag::err_flexible_array_empty_struct) 3386 << FD->getDeclName(); 3387 FD->setInvalidDecl(); 3388 EnclosingDecl->setInvalidDecl(); 3389 continue; 3390 } 3391 // Okay, we have a legal flexible array member at the end of the struct. 3392 if (Record) 3393 Record->setHasFlexibleArrayMember(true); 3394 } 3395 /// C99 6.7.2.1p2 - a struct ending in a flexible array member cannot be the 3396 /// field of another structure or the element of an array. 3397 if (const RecordType *FDTTy = FDTy->getAsRecordType()) { 3398 if (FDTTy->getDecl()->hasFlexibleArrayMember()) { 3399 // If this is a member of a union, then entire union becomes "flexible". 3400 if (Record && Record->isUnion()) { 3401 Record->setHasFlexibleArrayMember(true); 3402 } else { 3403 // If this is a struct/class and this is not the last element, reject 3404 // it. Note that GCC supports variable sized arrays in the middle of 3405 // structures. 3406 if (i != NumFields-1) { 3407 Diag(FD->getLocation(), diag::err_variable_sized_type_in_struct) 3408 << FD->getDeclName(); 3409 FD->setInvalidDecl(); 3410 EnclosingDecl->setInvalidDecl(); 3411 continue; 3412 } 3413 // We support flexible arrays at the end of structs in other structs 3414 // as an extension. 3415 Diag(FD->getLocation(), diag::ext_flexible_array_in_struct) 3416 << FD->getDeclName(); 3417 if (Record) 3418 Record->setHasFlexibleArrayMember(true); 3419 } 3420 } 3421 } 3422 /// A field cannot be an Objective-c object 3423 if (FDTy->isObjCInterfaceType()) { 3424 Diag(FD->getLocation(), diag::err_statically_allocated_object) 3425 << FD->getDeclName(); 3426 FD->setInvalidDecl(); 3427 EnclosingDecl->setInvalidDecl(); 3428 continue; 3429 } 3430 // Keep track of the number of named members. 3431 if (FD->getIdentifier()) 3432 ++NumNamedMembers; 3433 } 3434 3435 // Okay, we successfully defined 'Record'. 3436 if (Record) { 3437 Record->completeDefinition(Context); 3438 } else { 3439 ObjCIvarDecl **ClsFields = reinterpret_cast<ObjCIvarDecl**>(&RecFields[0]); 3440 if (ObjCInterfaceDecl *ID = dyn_cast<ObjCInterfaceDecl>(EnclosingDecl)) { 3441 ID->addInstanceVariablesToClass(ClsFields, RecFields.size(), RBrac); 3442 // Must enforce the rule that ivars in the base classes may not be 3443 // duplicates. 3444 if (ID->getSuperClass()) { 3445 for (ObjCInterfaceDecl::ivar_iterator IVI = ID->ivar_begin(), 3446 IVE = ID->ivar_end(); IVI != IVE; ++IVI) { 3447 ObjCIvarDecl* Ivar = (*IVI); 3448 IdentifierInfo *II = Ivar->getIdentifier(); 3449 ObjCIvarDecl* prevIvar = ID->getSuperClass()->FindIvarDeclaration(II); 3450 if (prevIvar) { 3451 Diag(Ivar->getLocation(), diag::err_duplicate_member) << II; 3452 Diag(prevIvar->getLocation(), diag::note_previous_declaration); 3453 } 3454 } 3455 } 3456 } 3457 else if (ObjCImplementationDecl *IMPDecl = 3458 dyn_cast<ObjCImplementationDecl>(EnclosingDecl)) { 3459 assert(IMPDecl && "ActOnFields - missing ObjCImplementationDecl"); 3460 IMPDecl->ObjCAddInstanceVariablesToClassImpl(ClsFields, RecFields.size()); 3461 CheckImplementationIvars(IMPDecl, ClsFields, RecFields.size(), RBrac); 3462 } 3463 } 3464 3465 if (Attr) 3466 ProcessDeclAttributeList(Record, Attr); 3467} 3468 3469Sema::DeclTy *Sema::ActOnEnumConstant(Scope *S, DeclTy *theEnumDecl, 3470 DeclTy *lastEnumConst, 3471 SourceLocation IdLoc, IdentifierInfo *Id, 3472 SourceLocation EqualLoc, ExprTy *val) { 3473 EnumDecl *TheEnumDecl = cast<EnumDecl>(static_cast<Decl*>(theEnumDecl)); 3474 EnumConstantDecl *LastEnumConst = 3475 cast_or_null<EnumConstantDecl>(static_cast<Decl*>(lastEnumConst)); 3476 Expr *Val = static_cast<Expr*>(val); 3477 3478 // The scope passed in may not be a decl scope. Zip up the scope tree until 3479 // we find one that is. 3480 S = getNonFieldDeclScope(S); 3481 3482 // Verify that there isn't already something declared with this name in this 3483 // scope. 3484 Decl *PrevDecl = LookupDecl(Id, Decl::IDNS_Ordinary, S); 3485 if (PrevDecl && PrevDecl->isTemplateParameter()) { 3486 // Maybe we will complain about the shadowed template parameter. 3487 DiagnoseTemplateParameterShadow(IdLoc, PrevDecl); 3488 // Just pretend that we didn't see the previous declaration. 3489 PrevDecl = 0; 3490 } 3491 3492 if (PrevDecl) { 3493 // When in C++, we may get a TagDecl with the same name; in this case the 3494 // enum constant will 'hide' the tag. 3495 assert((getLangOptions().CPlusPlus || !isa<TagDecl>(PrevDecl)) && 3496 "Received TagDecl when not in C++!"); 3497 if (!isa<TagDecl>(PrevDecl) && isDeclInScope(PrevDecl, CurContext, S)) { 3498 if (isa<EnumConstantDecl>(PrevDecl)) 3499 Diag(IdLoc, diag::err_redefinition_of_enumerator) << Id; 3500 else 3501 Diag(IdLoc, diag::err_redefinition) << Id; 3502 Diag(PrevDecl->getLocation(), diag::note_previous_definition); 3503 delete Val; 3504 return 0; 3505 } 3506 } 3507 3508 llvm::APSInt EnumVal(32); 3509 QualType EltTy; 3510 if (Val) { 3511 // Make sure to promote the operand type to int. 3512 UsualUnaryConversions(Val); 3513 3514 // C99 6.7.2.2p2: Make sure we have an integer constant expression. 3515 SourceLocation ExpLoc; 3516 if (VerifyIntegerConstantExpression(Val, &EnumVal)) { 3517 delete Val; 3518 Val = 0; // Just forget about it. 3519 } else { 3520 EltTy = Val->getType(); 3521 } 3522 } 3523 3524 if (!Val) { 3525 if (LastEnumConst) { 3526 // Assign the last value + 1. 3527 EnumVal = LastEnumConst->getInitVal(); 3528 ++EnumVal; 3529 3530 // Check for overflow on increment. 3531 if (EnumVal < LastEnumConst->getInitVal()) 3532 Diag(IdLoc, diag::warn_enum_value_overflow); 3533 3534 EltTy = LastEnumConst->getType(); 3535 } else { 3536 // First value, set to zero. 3537 EltTy = Context.IntTy; 3538 EnumVal.zextOrTrunc(static_cast<uint32_t>(Context.getTypeSize(EltTy))); 3539 } 3540 } 3541 3542 EnumConstantDecl *New = 3543 EnumConstantDecl::Create(Context, TheEnumDecl, IdLoc, Id, EltTy, 3544 Val, EnumVal, 3545 LastEnumConst); 3546 3547 // Register this decl in the current scope stack. 3548 PushOnScopeChains(New, S); 3549 3550 return New; 3551} 3552 3553// FIXME: For consistency with ActOnFields(), we should have the parser 3554// pass in the source location for the left/right braces. 3555void Sema::ActOnEnumBody(SourceLocation EnumLoc, DeclTy *EnumDeclX, 3556 DeclTy **Elements, unsigned NumElements) { 3557 EnumDecl *Enum = cast<EnumDecl>(static_cast<Decl*>(EnumDeclX)); 3558 QualType EnumType = Context.getTypeDeclType(Enum); 3559 3560 if (EnumType->getAsEnumType()->getDecl()->isDefinition()) { 3561 EnumDecl *Def = EnumType->getAsEnumType()->getDecl(); 3562 // Diagnose code like: 3563 // enum e0 { 3564 // E0 = sizeof(enum e0 { E1 }) 3565 // }; 3566 Diag(Def->getLocation(), diag::err_nested_redefinition) 3567 << Enum->getDeclName(); 3568 Diag(Enum->getLocation(), diag::note_previous_definition); 3569 Enum->setInvalidDecl(); 3570 return; 3571 } 3572 3573 // TODO: If the result value doesn't fit in an int, it must be a long or long 3574 // long value. ISO C does not support this, but GCC does as an extension, 3575 // emit a warning. 3576 unsigned IntWidth = Context.Target.getIntWidth(); 3577 3578 // Verify that all the values are okay, compute the size of the values, and 3579 // reverse the list. 3580 unsigned NumNegativeBits = 0; 3581 unsigned NumPositiveBits = 0; 3582 3583 // Keep track of whether all elements have type int. 3584 bool AllElementsInt = true; 3585 3586 for (unsigned i = 0; i != NumElements; ++i) { 3587 EnumConstantDecl *ECD = 3588 cast_or_null<EnumConstantDecl>(static_cast<Decl*>(Elements[i])); 3589 if (!ECD) continue; // Already issued a diagnostic. 3590 3591 // If the enum value doesn't fit in an int, emit an extension warning. 3592 const llvm::APSInt &InitVal = ECD->getInitVal(); 3593 assert(InitVal.getBitWidth() >= IntWidth && 3594 "Should have promoted value to int"); 3595 if (InitVal.getBitWidth() > IntWidth) { 3596 llvm::APSInt V(InitVal); 3597 V.trunc(IntWidth); 3598 V.extend(InitVal.getBitWidth()); 3599 if (V != InitVal) 3600 Diag(ECD->getLocation(), diag::ext_enum_value_not_int) 3601 << InitVal.toString(10); 3602 } 3603 3604 // Keep track of the size of positive and negative values. 3605 if (InitVal.isUnsigned() || InitVal.isNonNegative()) 3606 NumPositiveBits = std::max(NumPositiveBits, 3607 (unsigned)InitVal.getActiveBits()); 3608 else 3609 NumNegativeBits = std::max(NumNegativeBits, 3610 (unsigned)InitVal.getMinSignedBits()); 3611 3612 // Keep track of whether every enum element has type int (very commmon). 3613 if (AllElementsInt) 3614 AllElementsInt = ECD->getType() == Context.IntTy; 3615 } 3616 3617 // Figure out the type that should be used for this enum. 3618 // FIXME: Support attribute(packed) on enums and -fshort-enums. 3619 QualType BestType; 3620 unsigned BestWidth; 3621 3622 if (NumNegativeBits) { 3623 // If there is a negative value, figure out the smallest integer type (of 3624 // int/long/longlong) that fits. 3625 if (NumNegativeBits <= IntWidth && NumPositiveBits < IntWidth) { 3626 BestType = Context.IntTy; 3627 BestWidth = IntWidth; 3628 } else { 3629 BestWidth = Context.Target.getLongWidth(); 3630 3631 if (NumNegativeBits <= BestWidth && NumPositiveBits < BestWidth) 3632 BestType = Context.LongTy; 3633 else { 3634 BestWidth = Context.Target.getLongLongWidth(); 3635 3636 if (NumNegativeBits > BestWidth || NumPositiveBits >= BestWidth) 3637 Diag(Enum->getLocation(), diag::warn_enum_too_large); 3638 BestType = Context.LongLongTy; 3639 } 3640 } 3641 } else { 3642 // If there is no negative value, figure out which of uint, ulong, ulonglong 3643 // fits. 3644 if (NumPositiveBits <= IntWidth) { 3645 BestType = Context.UnsignedIntTy; 3646 BestWidth = IntWidth; 3647 } else if (NumPositiveBits <= 3648 (BestWidth = Context.Target.getLongWidth())) { 3649 BestType = Context.UnsignedLongTy; 3650 } else { 3651 BestWidth = Context.Target.getLongLongWidth(); 3652 assert(NumPositiveBits <= BestWidth && 3653 "How could an initializer get larger than ULL?"); 3654 BestType = Context.UnsignedLongLongTy; 3655 } 3656 } 3657 3658 // Loop over all of the enumerator constants, changing their types to match 3659 // the type of the enum if needed. 3660 for (unsigned i = 0; i != NumElements; ++i) { 3661 EnumConstantDecl *ECD = 3662 cast_or_null<EnumConstantDecl>(static_cast<Decl*>(Elements[i])); 3663 if (!ECD) continue; // Already issued a diagnostic. 3664 3665 // Standard C says the enumerators have int type, but we allow, as an 3666 // extension, the enumerators to be larger than int size. If each 3667 // enumerator value fits in an int, type it as an int, otherwise type it the 3668 // same as the enumerator decl itself. This means that in "enum { X = 1U }" 3669 // that X has type 'int', not 'unsigned'. 3670 if (ECD->getType() == Context.IntTy) { 3671 // Make sure the init value is signed. 3672 llvm::APSInt IV = ECD->getInitVal(); 3673 IV.setIsSigned(true); 3674 ECD->setInitVal(IV); 3675 3676 if (getLangOptions().CPlusPlus) 3677 // C++ [dcl.enum]p4: Following the closing brace of an 3678 // enum-specifier, each enumerator has the type of its 3679 // enumeration. 3680 ECD->setType(EnumType); 3681 continue; // Already int type. 3682 } 3683 3684 // Determine whether the value fits into an int. 3685 llvm::APSInt InitVal = ECD->getInitVal(); 3686 bool FitsInInt; 3687 if (InitVal.isUnsigned() || !InitVal.isNegative()) 3688 FitsInInt = InitVal.getActiveBits() < IntWidth; 3689 else 3690 FitsInInt = InitVal.getMinSignedBits() <= IntWidth; 3691 3692 // If it fits into an integer type, force it. Otherwise force it to match 3693 // the enum decl type. 3694 QualType NewTy; 3695 unsigned NewWidth; 3696 bool NewSign; 3697 if (FitsInInt) { 3698 NewTy = Context.IntTy; 3699 NewWidth = IntWidth; 3700 NewSign = true; 3701 } else if (ECD->getType() == BestType) { 3702 // Already the right type! 3703 if (getLangOptions().CPlusPlus) 3704 // C++ [dcl.enum]p4: Following the closing brace of an 3705 // enum-specifier, each enumerator has the type of its 3706 // enumeration. 3707 ECD->setType(EnumType); 3708 continue; 3709 } else { 3710 NewTy = BestType; 3711 NewWidth = BestWidth; 3712 NewSign = BestType->isSignedIntegerType(); 3713 } 3714 3715 // Adjust the APSInt value. 3716 InitVal.extOrTrunc(NewWidth); 3717 InitVal.setIsSigned(NewSign); 3718 ECD->setInitVal(InitVal); 3719 3720 // Adjust the Expr initializer and type. 3721 if (ECD->getInitExpr()) 3722 ECD->setInitExpr(new ImplicitCastExpr(NewTy, ECD->getInitExpr(), 3723 /*isLvalue=*/false)); 3724 if (getLangOptions().CPlusPlus) 3725 // C++ [dcl.enum]p4: Following the closing brace of an 3726 // enum-specifier, each enumerator has the type of its 3727 // enumeration. 3728 ECD->setType(EnumType); 3729 else 3730 ECD->setType(NewTy); 3731 } 3732 3733 Enum->completeDefinition(Context, BestType); 3734} 3735 3736Sema::DeclTy *Sema::ActOnFileScopeAsmDecl(SourceLocation Loc, 3737 ExprArg expr) { 3738 StringLiteral *AsmString = cast<StringLiteral>((Expr*)expr.release()); 3739 3740 return FileScopeAsmDecl::Create(Context, Loc, AsmString); 3741} 3742 3743 3744void Sema::ActOnPragmaPack(PragmaPackKind Kind, IdentifierInfo *Name, 3745 ExprTy *alignment, SourceLocation PragmaLoc, 3746 SourceLocation LParenLoc, SourceLocation RParenLoc) { 3747 Expr *Alignment = static_cast<Expr *>(alignment); 3748 3749 // If specified then alignment must be a "small" power of two. 3750 unsigned AlignmentVal = 0; 3751 if (Alignment) { 3752 llvm::APSInt Val; 3753 if (!Alignment->isIntegerConstantExpr(Val, Context) || 3754 !Val.isPowerOf2() || 3755 Val.getZExtValue() > 16) { 3756 Diag(PragmaLoc, diag::warn_pragma_pack_invalid_alignment); 3757 delete Alignment; 3758 return; // Ignore 3759 } 3760 3761 AlignmentVal = (unsigned) Val.getZExtValue(); 3762 } 3763 3764 switch (Kind) { 3765 case Action::PPK_Default: // pack([n]) 3766 PackContext.setAlignment(AlignmentVal); 3767 break; 3768 3769 case Action::PPK_Show: // pack(show) 3770 // Show the current alignment, making sure to show the right value 3771 // for the default. 3772 AlignmentVal = PackContext.getAlignment(); 3773 // FIXME: This should come from the target. 3774 if (AlignmentVal == 0) 3775 AlignmentVal = 8; 3776 Diag(PragmaLoc, diag::warn_pragma_pack_show) << AlignmentVal; 3777 break; 3778 3779 case Action::PPK_Push: // pack(push [, id] [, [n]) 3780 PackContext.push(Name); 3781 // Set the new alignment if specified. 3782 if (Alignment) 3783 PackContext.setAlignment(AlignmentVal); 3784 break; 3785 3786 case Action::PPK_Pop: // pack(pop [, id] [, n]) 3787 // MSDN, C/C++ Preprocessor Reference > Pragma Directives > pack: 3788 // "#pragma pack(pop, identifier, n) is undefined" 3789 if (Alignment && Name) 3790 Diag(PragmaLoc, diag::warn_pragma_pack_pop_identifer_and_alignment); 3791 3792 // Do the pop. 3793 if (!PackContext.pop(Name)) { 3794 // If a name was specified then failure indicates the name 3795 // wasn't found. Otherwise failure indicates the stack was 3796 // empty. 3797 Diag(PragmaLoc, diag::warn_pragma_pack_pop_failed) 3798 << (Name ? "no record matching name" : "stack empty"); 3799 3800 // FIXME: Warn about popping named records as MSVC does. 3801 } else { 3802 // Pop succeeded, set the new alignment if specified. 3803 if (Alignment) 3804 PackContext.setAlignment(AlignmentVal); 3805 } 3806 break; 3807 3808 default: 3809 assert(0 && "Invalid #pragma pack kind."); 3810 } 3811} 3812 3813bool PragmaPackStack::pop(IdentifierInfo *Name) { 3814 if (Stack.empty()) 3815 return false; 3816 3817 // If name is empty just pop top. 3818 if (!Name) { 3819 Alignment = Stack.back().first; 3820 Stack.pop_back(); 3821 return true; 3822 } 3823 3824 // Otherwise, find the named record. 3825 for (unsigned i = Stack.size(); i != 0; ) { 3826 --i; 3827 if (Stack[i].second == Name) { 3828 // Found it, pop up to and including this record. 3829 Alignment = Stack[i].first; 3830 Stack.erase(Stack.begin() + i, Stack.end()); 3831 return true; 3832 } 3833 } 3834 3835 return false; 3836} 3837