SemaDecl.cpp revision 5e77adeee0a6117f659a5046badcb97fe6fedb67
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/ASTConsumer.h" 16#include "clang/AST/ASTContext.h" 17#include "clang/AST/Attr.h" 18#include "clang/AST/Builtins.h" 19#include "clang/AST/Decl.h" 20#include "clang/AST/DeclCXX.h" 21#include "clang/AST/Expr.h" 22#include "clang/AST/Type.h" 23#include "clang/Parse/DeclSpec.h" 24#include "clang/Parse/Scope.h" 25#include "clang/Basic/LangOptions.h" 26#include "clang/Basic/TargetInfo.h" 27#include "clang/Basic/SourceManager.h" 28#include "clang/AST/ExprCXX.h" 29// FIXME: layering (ideally, Sema shouldn't be dependent on Lex API's) 30#include "clang/Lex/Preprocessor.h" 31#include "clang/Lex/HeaderSearch.h" 32#include "llvm/ADT/SmallString.h" 33#include "llvm/ADT/SmallSet.h" 34#include "llvm/ADT/DenseSet.h" 35using namespace clang; 36 37Sema::DeclTy *Sema::isTypeName(const IdentifierInfo &II, Scope *S) { 38 Decl *IIDecl = LookupDecl(&II, Decl::IDNS_Ordinary, S, false); 39 40 if (IIDecl && (isa<TypedefDecl>(IIDecl) || 41 isa<ObjCInterfaceDecl>(IIDecl) || 42 isa<TagDecl>(IIDecl))) 43 return IIDecl; 44 return 0; 45} 46 47void Sema::PushDeclContext(DeclContext *DC) { 48 assert( ( (isa<ObjCMethodDecl>(DC) && isa<TranslationUnitDecl>(CurContext)) 49 || DC->getParent() == CurContext ) && 50 "The next DeclContext should be directly contained in the current one."); 51 CurContext = DC; 52} 53 54void Sema::PopDeclContext() { 55 assert(CurContext && "DeclContext imbalance!"); 56 // If CurContext is a ObjC method, getParent() will return NULL. 57 CurContext = isa<ObjCMethodDecl>(CurContext) 58 ? Context.getTranslationUnitDecl() 59 : CurContext->getParent(); 60} 61 62/// Add this decl to the scope shadowed decl chains. 63void Sema::PushOnScopeChains(NamedDecl *D, Scope *S) { 64 S->AddDecl(D); 65 66 // C++ [basic.scope]p4: 67 // -- exactly one declaration shall declare a class name or 68 // enumeration name that is not a typedef name and the other 69 // declarations shall all refer to the same object or 70 // enumerator, or all refer to functions and function templates; 71 // in this case the class name or enumeration name is hidden. 72 if (TagDecl *TD = dyn_cast<TagDecl>(D)) { 73 // We are pushing the name of a tag (enum or class). 74 IdentifierResolver::ctx_iterator 75 CIT = IdResolver.ctx_begin(TD->getIdentifier(), TD->getDeclContext()); 76 if (CIT != IdResolver.ctx_end(TD->getIdentifier()) && 77 IdResolver.isDeclInScope(*CIT, TD->getDeclContext(), S)) { 78 // There is already a declaration with the same name in the same 79 // scope. It must be found before we find the new declaration, 80 // so swap the order on the shadowed declaration chain. 81 82 IdResolver.AddShadowedDecl(TD, *CIT); 83 return; 84 } 85 } 86 87 IdResolver.AddDecl(D); 88} 89 90void Sema::ActOnPopScope(SourceLocation Loc, Scope *S) { 91 if (S->decl_empty()) return; 92 assert((S->getFlags() & Scope::DeclScope) &&"Scope shouldn't contain decls!"); 93 94 for (Scope::decl_iterator I = S->decl_begin(), E = S->decl_end(); 95 I != E; ++I) { 96 Decl *TmpD = static_cast<Decl*>(*I); 97 assert(TmpD && "This decl didn't get pushed??"); 98 99 if (isa<CXXFieldDecl>(TmpD)) continue; 100 101 assert(isa<ScopedDecl>(TmpD) && "Decl isn't ScopedDecl?"); 102 ScopedDecl *D = cast<ScopedDecl>(TmpD); 103 104 IdentifierInfo *II = D->getIdentifier(); 105 if (!II) continue; 106 107 // We only want to remove the decls from the identifier decl chains for local 108 // scopes, when inside a function/method. 109 if (S->getFnParent() != 0) 110 IdResolver.RemoveDecl(D); 111 112 // Chain this decl to the containing DeclContext. 113 D->setNext(CurContext->getDeclChain()); 114 CurContext->setDeclChain(D); 115 } 116} 117 118/// getObjCInterfaceDecl - Look up a for a class declaration in the scope. 119/// return 0 if one not found. 120ObjCInterfaceDecl *Sema::getObjCInterfaceDecl(IdentifierInfo *Id) { 121 // The third "scope" argument is 0 since we aren't enabling lazy built-in 122 // creation from this context. 123 Decl *IDecl = LookupDecl(Id, Decl::IDNS_Ordinary, 0, false); 124 125 return dyn_cast_or_null<ObjCInterfaceDecl>(IDecl); 126} 127 128/// LookupDecl - Look up the inner-most declaration in the specified 129/// namespace. 130Decl *Sema::LookupDecl(const IdentifierInfo *II, unsigned NSI, 131 Scope *S, bool enableLazyBuiltinCreation) { 132 if (II == 0) return 0; 133 unsigned NS = NSI; 134 if (getLangOptions().CPlusPlus && (NS & Decl::IDNS_Ordinary)) 135 NS |= Decl::IDNS_Tag; 136 137 // Scan up the scope chain looking for a decl that matches this identifier 138 // that is in the appropriate namespace. This search should not take long, as 139 // shadowing of names is uncommon, and deep shadowing is extremely uncommon. 140 for (IdentifierResolver::iterator 141 I = IdResolver.begin(II, CurContext), E = IdResolver.end(II); I != E; ++I) 142 if ((*I)->getIdentifierNamespace() & NS) 143 return *I; 144 145 // If we didn't find a use of this identifier, and if the identifier 146 // corresponds to a compiler builtin, create the decl object for the builtin 147 // now, injecting it into translation unit scope, and return it. 148 if (NS & Decl::IDNS_Ordinary) { 149 if (enableLazyBuiltinCreation) { 150 // If this is a builtin on this (or all) targets, create the decl. 151 if (unsigned BuiltinID = II->getBuiltinID()) 152 return LazilyCreateBuiltin((IdentifierInfo *)II, BuiltinID, S); 153 } 154 if (getLangOptions().ObjC1) { 155 // @interface and @compatibility_alias introduce typedef-like names. 156 // Unlike typedef's, they can only be introduced at file-scope (and are 157 // therefore not scoped decls). They can, however, be shadowed by 158 // other names in IDNS_Ordinary. 159 ObjCInterfaceDeclsTy::iterator IDI = ObjCInterfaceDecls.find(II); 160 if (IDI != ObjCInterfaceDecls.end()) 161 return IDI->second; 162 ObjCAliasTy::iterator I = ObjCAliasDecls.find(II); 163 if (I != ObjCAliasDecls.end()) 164 return I->second->getClassInterface(); 165 } 166 } 167 return 0; 168} 169 170void Sema::InitBuiltinVaListType() { 171 if (!Context.getBuiltinVaListType().isNull()) 172 return; 173 174 IdentifierInfo *VaIdent = &Context.Idents.get("__builtin_va_list"); 175 Decl *VaDecl = LookupDecl(VaIdent, Decl::IDNS_Ordinary, TUScope); 176 TypedefDecl *VaTypedef = cast<TypedefDecl>(VaDecl); 177 Context.setBuiltinVaListType(Context.getTypedefType(VaTypedef)); 178} 179 180/// LazilyCreateBuiltin - The specified Builtin-ID was first used at file scope. 181/// lazily create a decl for it. 182ScopedDecl *Sema::LazilyCreateBuiltin(IdentifierInfo *II, unsigned bid, 183 Scope *S) { 184 Builtin::ID BID = (Builtin::ID)bid; 185 186 if (BID == Builtin::BI__builtin_va_start || 187 BID == Builtin::BI__builtin_va_copy || 188 BID == Builtin::BI__builtin_va_end) 189 InitBuiltinVaListType(); 190 191 QualType R = Context.BuiltinInfo.GetBuiltinType(BID, Context); 192 FunctionDecl *New = FunctionDecl::Create(Context, 193 Context.getTranslationUnitDecl(), 194 SourceLocation(), II, R, 195 FunctionDecl::Extern, false, 0); 196 197 // Create Decl objects for each parameter, adding them to the 198 // FunctionDecl. 199 if (FunctionTypeProto *FT = dyn_cast<FunctionTypeProto>(R)) { 200 llvm::SmallVector<ParmVarDecl*, 16> Params; 201 for (unsigned i = 0, e = FT->getNumArgs(); i != e; ++i) 202 Params.push_back(ParmVarDecl::Create(Context, New, SourceLocation(), 0, 203 FT->getArgType(i), VarDecl::None, 0, 204 0)); 205 New->setParams(&Params[0], Params.size()); 206 } 207 208 209 210 // TUScope is the translation-unit scope to insert this function into. 211 PushOnScopeChains(New, TUScope); 212 return New; 213} 214 215/// MergeTypeDefDecl - We just parsed a typedef 'New' which has the same name 216/// and scope as a previous declaration 'Old'. Figure out how to resolve this 217/// situation, merging decls or emitting diagnostics as appropriate. 218/// 219TypedefDecl *Sema::MergeTypeDefDecl(TypedefDecl *New, Decl *OldD) { 220 // Verify the old decl was also a typedef. 221 TypedefDecl *Old = dyn_cast<TypedefDecl>(OldD); 222 if (!Old) { 223 Diag(New->getLocation(), diag::err_redefinition_different_kind, 224 New->getName()); 225 Diag(OldD->getLocation(), diag::err_previous_definition); 226 return New; 227 } 228 229 // Allow multiple definitions for ObjC built-in typedefs. 230 // FIXME: Verify the underlying types are equivalent! 231 if (getLangOptions().ObjC1 && isBuiltinObjCType(New)) 232 return Old; 233 234 if (getLangOptions().Microsoft) return New; 235 236 // Redeclaration of a type is a constraint violation (6.7.2.3p1). 237 // Apparently GCC, Intel, and Sun all silently ignore the redeclaration if 238 // *either* declaration is in a system header. The code below implements 239 // this adhoc compatibility rule. FIXME: The following code will not 240 // work properly when compiling ".i" files (containing preprocessed output). 241 SourceManager &SrcMgr = Context.getSourceManager(); 242 HeaderSearch &HdrInfo = PP.getHeaderSearchInfo(); 243 const FileEntry *OldDeclFile = SrcMgr.getFileEntryForLoc(Old->getLocation()); 244 if (OldDeclFile) { 245 DirectoryLookup::DirType OldDirType = HdrInfo.getFileDirFlavor(OldDeclFile); 246 // Allow reclarations in both SystemHeaderDir and ExternCSystemHeaderDir. 247 if (OldDirType != DirectoryLookup::NormalHeaderDir) 248 return New; 249 } 250 const FileEntry *NewDeclFile = SrcMgr.getFileEntryForLoc(New->getLocation()); 251 if (NewDeclFile) { 252 DirectoryLookup::DirType NewDirType = HdrInfo.getFileDirFlavor(NewDeclFile); 253 // Allow reclarations in both SystemHeaderDir and ExternCSystemHeaderDir. 254 if (NewDirType != DirectoryLookup::NormalHeaderDir) 255 return New; 256 } 257 258 Diag(New->getLocation(), diag::err_redefinition, New->getName()); 259 Diag(Old->getLocation(), diag::err_previous_definition); 260 return New; 261} 262 263/// DeclhasAttr - returns true if decl Declaration already has the target attribute. 264static bool DeclHasAttr(const Decl *decl, const Attr *target) { 265 for (const Attr *attr = decl->getAttrs(); attr; attr = attr->getNext()) 266 if (attr->getKind() == target->getKind()) 267 return true; 268 269 return false; 270} 271 272/// MergeAttributes - append attributes from the Old decl to the New one. 273static void MergeAttributes(Decl *New, Decl *Old) { 274 Attr *attr = const_cast<Attr*>(Old->getAttrs()), *tmp; 275 276 while (attr) { 277 tmp = attr; 278 attr = attr->getNext(); 279 280 if (!DeclHasAttr(New, tmp)) { 281 New->addAttr(tmp); 282 } else { 283 tmp->setNext(0); 284 delete(tmp); 285 } 286 } 287 288 Old->invalidateAttrs(); 289} 290 291/// MergeFunctionDecl - We just parsed a function 'New' from 292/// declarator D which has the same name and scope as a previous 293/// declaration 'Old'. Figure out how to resolve this situation, 294/// merging decls or emitting diagnostics as appropriate. 295/// Redeclaration will be set true if thisNew is a redeclaration OldD. 296FunctionDecl * 297Sema::MergeFunctionDecl(FunctionDecl *New, Decl *OldD, bool &Redeclaration) { 298 Redeclaration = false; 299 // Verify the old decl was also a function. 300 FunctionDecl *Old = dyn_cast<FunctionDecl>(OldD); 301 if (!Old) { 302 Diag(New->getLocation(), diag::err_redefinition_different_kind, 303 New->getName()); 304 Diag(OldD->getLocation(), diag::err_previous_definition); 305 return New; 306 } 307 308 QualType OldQType = Context.getCanonicalType(Old->getType()); 309 QualType NewQType = Context.getCanonicalType(New->getType()); 310 311 // C++ [dcl.fct]p3: 312 // All declarations for a function shall agree exactly in both the 313 // return type and the parameter-type-list. 314 if (getLangOptions().CPlusPlus && OldQType == NewQType) { 315 MergeAttributes(New, Old); 316 Redeclaration = true; 317 return MergeCXXFunctionDecl(New, Old); 318 } 319 320 // C: Function types need to be compatible, not identical. This handles 321 // duplicate function decls like "void f(int); void f(enum X);" properly. 322 if (!getLangOptions().CPlusPlus && 323 Context.functionTypesAreCompatible(OldQType, NewQType)) { 324 MergeAttributes(New, Old); 325 Redeclaration = true; 326 return New; 327 } 328 329 // A function that has already been declared has been redeclared or defined 330 // with a different type- show appropriate diagnostic 331 diag::kind PrevDiag; 332 if (Old->isThisDeclarationADefinition()) 333 PrevDiag = diag::err_previous_definition; 334 else if (Old->isImplicit()) 335 PrevDiag = diag::err_previous_implicit_declaration; 336 else 337 PrevDiag = diag::err_previous_declaration; 338 339 // TODO: CHECK FOR CONFLICTS, multiple decls with same name in one scope. 340 // TODO: This is totally simplistic. It should handle merging functions 341 // together etc, merging extern int X; int X; ... 342 Diag(New->getLocation(), diag::err_conflicting_types, New->getName()); 343 Diag(Old->getLocation(), PrevDiag); 344 return New; 345} 346 347/// equivalentArrayTypes - Used to determine whether two array types are 348/// equivalent. 349/// We need to check this explicitly as an incomplete array definition is 350/// considered a VariableArrayType, so will not match a complete array 351/// definition that would be otherwise equivalent. 352static bool areEquivalentArrayTypes(QualType NewQType, QualType OldQType) { 353 const ArrayType *NewAT = NewQType->getAsArrayType(); 354 const ArrayType *OldAT = OldQType->getAsArrayType(); 355 356 if (!NewAT || !OldAT) 357 return false; 358 359 // If either (or both) array types in incomplete we need to strip off the 360 // outer VariableArrayType. Once the outer VAT is removed the remaining 361 // types must be identical if the array types are to be considered 362 // equivalent. 363 // eg. int[][1] and int[1][1] become 364 // VAT(null, CAT(1, int)) and CAT(1, CAT(1, int)) 365 // removing the outermost VAT gives 366 // CAT(1, int) and CAT(1, int) 367 // which are equal, therefore the array types are equivalent. 368 if (NewAT->isIncompleteArrayType() || OldAT->isIncompleteArrayType()) { 369 if (NewAT->getIndexTypeQualifier() != OldAT->getIndexTypeQualifier()) 370 return false; 371 NewQType = NewAT->getElementType().getCanonicalType(); 372 OldQType = OldAT->getElementType().getCanonicalType(); 373 } 374 375 return NewQType == OldQType; 376} 377 378/// MergeVarDecl - We just parsed a variable 'New' which has the same name 379/// and scope as a previous declaration 'Old'. Figure out how to resolve this 380/// situation, merging decls or emitting diagnostics as appropriate. 381/// 382/// FIXME: Need to carefully consider tentative definition rules (C99 6.9.2p2). 383/// For example, we incorrectly complain about i1, i4 from C99 6.9.2p4. 384/// 385VarDecl *Sema::MergeVarDecl(VarDecl *New, Decl *OldD) { 386 // Verify the old decl was also a variable. 387 VarDecl *Old = dyn_cast<VarDecl>(OldD); 388 if (!Old) { 389 Diag(New->getLocation(), diag::err_redefinition_different_kind, 390 New->getName()); 391 Diag(OldD->getLocation(), diag::err_previous_definition); 392 return New; 393 } 394 395 MergeAttributes(New, Old); 396 397 // Verify the types match. 398 QualType OldCType = Context.getCanonicalType(Old->getType()); 399 QualType NewCType = Context.getCanonicalType(New->getType()); 400 if (OldCType != NewCType && !areEquivalentArrayTypes(NewCType, OldCType)) { 401 Diag(New->getLocation(), diag::err_redefinition, New->getName()); 402 Diag(Old->getLocation(), diag::err_previous_definition); 403 return New; 404 } 405 // C99 6.2.2p4: Check if we have a static decl followed by a non-static. 406 if (New->getStorageClass() == VarDecl::Static && 407 (Old->getStorageClass() == VarDecl::None || 408 Old->getStorageClass() == VarDecl::Extern)) { 409 Diag(New->getLocation(), diag::err_static_non_static, New->getName()); 410 Diag(Old->getLocation(), diag::err_previous_definition); 411 return New; 412 } 413 // C99 6.2.2p4: Check if we have a non-static decl followed by a static. 414 if (New->getStorageClass() != VarDecl::Static && 415 Old->getStorageClass() == VarDecl::Static) { 416 Diag(New->getLocation(), diag::err_non_static_static, New->getName()); 417 Diag(Old->getLocation(), diag::err_previous_definition); 418 return New; 419 } 420 // We've verified the types match, now handle "tentative" definitions. 421 if (Old->isFileVarDecl() && New->isFileVarDecl()) { 422 // Handle C "tentative" external object definitions (C99 6.9.2). 423 bool OldIsTentative = false; 424 bool NewIsTentative = false; 425 426 if (!Old->getInit() && 427 (Old->getStorageClass() == VarDecl::None || 428 Old->getStorageClass() == VarDecl::Static)) 429 OldIsTentative = true; 430 431 // FIXME: this check doesn't work (since the initializer hasn't been 432 // attached yet). This check should be moved to FinalizeDeclaratorGroup. 433 // Unfortunately, by the time we get to FinializeDeclaratorGroup, we've 434 // thrown out the old decl. 435 if (!New->getInit() && 436 (New->getStorageClass() == VarDecl::None || 437 New->getStorageClass() == VarDecl::Static)) 438 ; // change to NewIsTentative = true; once the code is moved. 439 440 if (NewIsTentative || OldIsTentative) 441 return New; 442 } 443 // Handle __private_extern__ just like extern. 444 if (Old->getStorageClass() != VarDecl::Extern && 445 Old->getStorageClass() != VarDecl::PrivateExtern && 446 New->getStorageClass() != VarDecl::Extern && 447 New->getStorageClass() != VarDecl::PrivateExtern) { 448 Diag(New->getLocation(), diag::err_redefinition, New->getName()); 449 Diag(Old->getLocation(), diag::err_previous_definition); 450 } 451 return New; 452} 453 454/// CheckParmsForFunctionDef - Check that the parameters of the given 455/// function are appropriate for the definition of a function. This 456/// takes care of any checks that cannot be performed on the 457/// declaration itself, e.g., that the types of each of the function 458/// parameters are complete. 459bool Sema::CheckParmsForFunctionDef(FunctionDecl *FD) { 460 bool HasInvalidParm = false; 461 for (unsigned p = 0, NumParams = FD->getNumParams(); p < NumParams; ++p) { 462 ParmVarDecl *Param = FD->getParamDecl(p); 463 464 // C99 6.7.5.3p4: the parameters in a parameter type list in a 465 // function declarator that is part of a function definition of 466 // that function shall not have incomplete type. 467 if (Param->getType()->isIncompleteType() && 468 !Param->isInvalidDecl()) { 469 Diag(Param->getLocation(), diag::err_typecheck_decl_incomplete_type, 470 Param->getType().getAsString()); 471 Param->setInvalidDecl(); 472 HasInvalidParm = true; 473 } 474 } 475 476 return HasInvalidParm; 477} 478 479/// CreateImplicitParameter - Creates an implicit function parameter 480/// in the scope S and with the given type. This routine is used, for 481/// example, to create the implicit "self" parameter in an Objective-C 482/// method. 483ImplicitParamDecl * 484Sema::CreateImplicitParameter(Scope *S, IdentifierInfo *Id, 485 SourceLocation IdLoc, QualType Type) { 486 ImplicitParamDecl *New = ImplicitParamDecl::Create(Context, CurContext, 487 IdLoc, Id, Type, 0); 488 if (Id) 489 PushOnScopeChains(New, S); 490 491 return New; 492} 493 494/// ParsedFreeStandingDeclSpec - This method is invoked when a declspec with 495/// no declarator (e.g. "struct foo;") is parsed. 496Sema::DeclTy *Sema::ParsedFreeStandingDeclSpec(Scope *S, DeclSpec &DS) { 497 // TODO: emit error on 'int;' or 'const enum foo;'. 498 // TODO: emit error on 'typedef int;' 499 // if (!DS.isMissingDeclaratorOk()) Diag(...); 500 501 return dyn_cast_or_null<TagDecl>(static_cast<Decl *>(DS.getTypeRep())); 502} 503 504bool Sema::CheckSingleInitializer(Expr *&Init, QualType DeclType) { 505 // Get the type before calling CheckSingleAssignmentConstraints(), since 506 // it can promote the expression. 507 QualType InitType = Init->getType(); 508 509 AssignConvertType ConvTy = CheckSingleAssignmentConstraints(DeclType, Init); 510 return DiagnoseAssignmentResult(ConvTy, Init->getLocStart(), DeclType, 511 InitType, Init, "initializing"); 512} 513 514bool Sema::CheckStringLiteralInit(StringLiteral *strLiteral, QualType &DeclT) { 515 if (const IncompleteArrayType *IAT = DeclT->getAsIncompleteArrayType()) { 516 // C99 6.7.8p14. We have an array of character type with unknown size 517 // being initialized to a string literal. 518 llvm::APSInt ConstVal(32); 519 ConstVal = strLiteral->getByteLength() + 1; 520 // Return a new array type (C99 6.7.8p22). 521 DeclT = Context.getConstantArrayType(IAT->getElementType(), ConstVal, 522 ArrayType::Normal, 0); 523 } else if (const ConstantArrayType *CAT = DeclT->getAsConstantArrayType()) { 524 // C99 6.7.8p14. We have an array of character type with known size. 525 if (strLiteral->getByteLength() > (unsigned)CAT->getMaximumElements()) 526 Diag(strLiteral->getSourceRange().getBegin(), 527 diag::warn_initializer_string_for_char_array_too_long, 528 strLiteral->getSourceRange()); 529 } else { 530 assert(0 && "HandleStringLiteralInit(): Invalid array type"); 531 } 532 // Set type from "char *" to "constant array of char". 533 strLiteral->setType(DeclT); 534 // For now, we always return false (meaning success). 535 return false; 536} 537 538StringLiteral *Sema::IsStringLiteralInit(Expr *Init, QualType DeclType) { 539 const ArrayType *AT = DeclType->getAsArrayType(); 540 if (AT && AT->getElementType()->isCharType()) { 541 return dyn_cast<StringLiteral>(Init); 542 } 543 return 0; 544} 545 546bool Sema::CheckInitializerTypes(Expr *&Init, QualType &DeclType) { 547 // C99 6.7.8p3: The type of the entity to be initialized shall be an array 548 // of unknown size ("[]") or an object type that is not a variable array type. 549 if (const VariableArrayType *VAT = DeclType->getAsVariableArrayType()) 550 return Diag(VAT->getSizeExpr()->getLocStart(), 551 diag::err_variable_object_no_init, 552 VAT->getSizeExpr()->getSourceRange()); 553 554 InitListExpr *InitList = dyn_cast<InitListExpr>(Init); 555 if (!InitList) { 556 // FIXME: Handle wide strings 557 if (StringLiteral *strLiteral = IsStringLiteralInit(Init, DeclType)) 558 return CheckStringLiteralInit(strLiteral, DeclType); 559 560 if (DeclType->isArrayType()) 561 return Diag(Init->getLocStart(), 562 diag::err_array_init_list_required, 563 Init->getSourceRange()); 564 565 return CheckSingleInitializer(Init, DeclType); 566 } 567 568 InitListChecker CheckInitList(this, InitList, DeclType); 569 return CheckInitList.HadError(); 570} 571 572Sema::DeclTy * 573Sema::ActOnDeclarator(Scope *S, Declarator &D, DeclTy *lastDecl) { 574 ScopedDecl *LastDeclarator = dyn_cast_or_null<ScopedDecl>((Decl *)lastDecl); 575 IdentifierInfo *II = D.getIdentifier(); 576 577 // All of these full declarators require an identifier. If it doesn't have 578 // one, the ParsedFreeStandingDeclSpec action should be used. 579 if (II == 0) { 580 Diag(D.getDeclSpec().getSourceRange().getBegin(), 581 diag::err_declarator_need_ident, 582 D.getDeclSpec().getSourceRange(), D.getSourceRange()); 583 return 0; 584 } 585 586 // The scope passed in may not be a decl scope. Zip up the scope tree until 587 // we find one that is. 588 while ((S->getFlags() & Scope::DeclScope) == 0) 589 S = S->getParent(); 590 591 // See if this is a redefinition of a variable in the same scope. 592 Decl *PrevDecl = LookupDecl(II, Decl::IDNS_Ordinary, S); 593 ScopedDecl *New; 594 bool InvalidDecl = false; 595 596 // In C++, the previous declaration we find might be a tag type 597 // (class or enum). In this case, the new declaration will hide the 598 // tag type. 599 if (PrevDecl && PrevDecl->getIdentifierNamespace() == Decl::IDNS_Tag) 600 PrevDecl = 0; 601 602 QualType R = GetTypeForDeclarator(D, S); 603 assert(!R.isNull() && "GetTypeForDeclarator() returned null type"); 604 605 if (D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_typedef) { 606 // Check that there are no default arguments (C++ only). 607 if (getLangOptions().CPlusPlus) 608 CheckExtraCXXDefaultArguments(D); 609 610 TypedefDecl *NewTD = ParseTypedefDecl(S, D, R, LastDeclarator); 611 if (!NewTD) return 0; 612 613 // Handle attributes prior to checking for duplicates in MergeVarDecl 614 HandleDeclAttributes(NewTD, D.getDeclSpec().getAttributes(), 615 D.getAttributes()); 616 // Merge the decl with the existing one if appropriate. If the decl is 617 // in an outer scope, it isn't the same thing. 618 if (PrevDecl && IdResolver.isDeclInScope(PrevDecl, CurContext, S)) { 619 NewTD = MergeTypeDefDecl(NewTD, PrevDecl); 620 if (NewTD == 0) return 0; 621 } 622 New = NewTD; 623 if (S->getFnParent() == 0) { 624 // C99 6.7.7p2: If a typedef name specifies a variably modified type 625 // then it shall have block scope. 626 if (NewTD->getUnderlyingType()->isVariablyModifiedType()) { 627 // FIXME: Diagnostic needs to be fixed. 628 Diag(D.getIdentifierLoc(), diag::err_typecheck_illegal_vla); 629 InvalidDecl = true; 630 } 631 } 632 } else if (R.getTypePtr()->isFunctionType()) { 633 FunctionDecl::StorageClass SC = FunctionDecl::None; 634 switch (D.getDeclSpec().getStorageClassSpec()) { 635 default: assert(0 && "Unknown storage class!"); 636 case DeclSpec::SCS_auto: 637 case DeclSpec::SCS_register: 638 Diag(D.getIdentifierLoc(), diag::err_typecheck_sclass_func, 639 R.getAsString()); 640 InvalidDecl = true; 641 break; 642 case DeclSpec::SCS_unspecified: SC = FunctionDecl::None; break; 643 case DeclSpec::SCS_extern: SC = FunctionDecl::Extern; break; 644 case DeclSpec::SCS_static: SC = FunctionDecl::Static; break; 645 case DeclSpec::SCS_private_extern: SC = FunctionDecl::PrivateExtern;break; 646 } 647 648 bool isInline = D.getDeclSpec().isInlineSpecified(); 649 FunctionDecl *NewFD = FunctionDecl::Create(Context, CurContext, 650 D.getIdentifierLoc(), 651 II, R, SC, isInline, 652 LastDeclarator); 653 // Handle attributes. 654 HandleDeclAttributes(NewFD, D.getDeclSpec().getAttributes(), 655 D.getAttributes()); 656 657 // Copy the parameter declarations from the declarator D to 658 // the function declaration NewFD, if they are available. 659 if (D.getNumTypeObjects() > 0 && 660 D.getTypeObject(0).Fun.hasPrototype) { 661 DeclaratorChunk::FunctionTypeInfo &FTI = D.getTypeObject(0).Fun; 662 663 // Create Decl objects for each parameter, adding them to the 664 // FunctionDecl. 665 llvm::SmallVector<ParmVarDecl*, 16> Params; 666 667 // Check for C99 6.7.5.3p10 - foo(void) is a non-varargs 668 // function that takes no arguments, not a function that takes a 669 // single void argument. 670 // We let through "const void" here because Sema::GetTypeForDeclarator 671 // already checks for that case. 672 if (FTI.NumArgs == 1 && !FTI.isVariadic && FTI.ArgInfo[0].Ident == 0 && 673 FTI.ArgInfo[0].Param && 674 ((ParmVarDecl*)FTI.ArgInfo[0].Param)->getType()->isVoidType()) { 675 // empty arg list, don't push any params. 676 ParmVarDecl *Param = (ParmVarDecl*)FTI.ArgInfo[0].Param; 677 678 // In C++, the empty parameter-type-list must be spelled "void"; a 679 // typedef of void is not permitted. 680 if (getLangOptions().CPlusPlus && 681 Param->getType().getUnqualifiedType() != Context.VoidTy) { 682 Diag(Param->getLocation(), diag::ext_param_typedef_of_void); 683 } 684 685 } else { 686 for (unsigned i = 0, e = FTI.NumArgs; i != e; ++i) 687 Params.push_back((ParmVarDecl *)FTI.ArgInfo[i].Param); 688 } 689 690 NewFD->setParams(&Params[0], Params.size()); 691 } 692 693 // Merge the decl with the existing one if appropriate. Since C functions 694 // are in a flat namespace, make sure we consider decls in outer scopes. 695 if (PrevDecl && 696 (!getLangOptions().CPlusPlus || 697 IdResolver.isDeclInScope(PrevDecl, CurContext, S)) ) { 698 bool Redeclaration = false; 699 NewFD = MergeFunctionDecl(NewFD, PrevDecl, Redeclaration); 700 if (NewFD == 0) return 0; 701 if (Redeclaration) { 702 NewFD->setPreviousDeclaration(cast<FunctionDecl>(PrevDecl)); 703 } 704 } 705 New = NewFD; 706 707 // In C++, check default arguments now that we have merged decls. 708 if (getLangOptions().CPlusPlus) 709 CheckCXXDefaultArguments(NewFD); 710 } else { 711 // Check that there are no default arguments (C++ only). 712 if (getLangOptions().CPlusPlus) 713 CheckExtraCXXDefaultArguments(D); 714 715 if (R.getTypePtr()->isObjCInterfaceType()) { 716 Diag(D.getIdentifierLoc(), diag::err_statically_allocated_object, 717 D.getIdentifier()->getName()); 718 InvalidDecl = true; 719 } 720 721 VarDecl *NewVD; 722 VarDecl::StorageClass SC; 723 switch (D.getDeclSpec().getStorageClassSpec()) { 724 default: assert(0 && "Unknown storage class!"); 725 case DeclSpec::SCS_unspecified: SC = VarDecl::None; break; 726 case DeclSpec::SCS_extern: SC = VarDecl::Extern; break; 727 case DeclSpec::SCS_static: SC = VarDecl::Static; break; 728 case DeclSpec::SCS_auto: SC = VarDecl::Auto; break; 729 case DeclSpec::SCS_register: SC = VarDecl::Register; break; 730 case DeclSpec::SCS_private_extern: SC = VarDecl::PrivateExtern; break; 731 } 732 if (S->getFnParent() == 0) { 733 // C99 6.9p2: The storage-class specifiers auto and register shall not 734 // appear in the declaration specifiers in an external declaration. 735 if (SC == VarDecl::Auto || SC == VarDecl::Register) { 736 Diag(D.getIdentifierLoc(), diag::err_typecheck_sclass_fscope, 737 R.getAsString()); 738 InvalidDecl = true; 739 } 740 NewVD = VarDecl::Create(Context, CurContext, D.getIdentifierLoc(), 741 II, R, SC, LastDeclarator); 742 } else { 743 NewVD = VarDecl::Create(Context, CurContext, D.getIdentifierLoc(), 744 II, R, SC, LastDeclarator); 745 } 746 // Handle attributes prior to checking for duplicates in MergeVarDecl 747 HandleDeclAttributes(NewVD, D.getDeclSpec().getAttributes(), 748 D.getAttributes()); 749 750 // Emit an error if an address space was applied to decl with local storage. 751 // This includes arrays of objects with address space qualifiers, but not 752 // automatic variables that point to other address spaces. 753 // ISO/IEC TR 18037 S5.1.2 754 if (NewVD->hasLocalStorage() && (NewVD->getType().getAddressSpace() != 0)) { 755 Diag(D.getIdentifierLoc(), diag::err_as_qualified_auto_decl); 756 InvalidDecl = true; 757 } 758 // Merge the decl with the existing one if appropriate. If the decl is 759 // in an outer scope, it isn't the same thing. 760 if (PrevDecl && IdResolver.isDeclInScope(PrevDecl, CurContext, S)) { 761 NewVD = MergeVarDecl(NewVD, PrevDecl); 762 if (NewVD == 0) return 0; 763 } 764 New = NewVD; 765 } 766 767 // If this has an identifier, add it to the scope stack. 768 if (II) 769 PushOnScopeChains(New, S); 770 // If any semantic error occurred, mark the decl as invalid. 771 if (D.getInvalidType() || InvalidDecl) 772 New->setInvalidDecl(); 773 774 return New; 775} 776 777bool Sema::CheckAddressConstantExpressionLValue(const Expr* Init) { 778 switch (Init->getStmtClass()) { 779 default: 780 Diag(Init->getExprLoc(), 781 diag::err_init_element_not_constant, Init->getSourceRange()); 782 return true; 783 case Expr::ParenExprClass: { 784 const ParenExpr* PE = cast<ParenExpr>(Init); 785 return CheckAddressConstantExpressionLValue(PE->getSubExpr()); 786 } 787 case Expr::CompoundLiteralExprClass: 788 return cast<CompoundLiteralExpr>(Init)->isFileScope(); 789 case Expr::DeclRefExprClass: { 790 const Decl *D = cast<DeclRefExpr>(Init)->getDecl(); 791 if (const VarDecl *VD = dyn_cast<VarDecl>(D)) { 792 if (VD->hasGlobalStorage()) 793 return false; 794 Diag(Init->getExprLoc(), 795 diag::err_init_element_not_constant, Init->getSourceRange()); 796 return true; 797 } 798 if (isa<FunctionDecl>(D)) 799 return false; 800 Diag(Init->getExprLoc(), 801 diag::err_init_element_not_constant, Init->getSourceRange()); 802 return true; 803 } 804 case Expr::MemberExprClass: { 805 const MemberExpr *M = cast<MemberExpr>(Init); 806 if (M->isArrow()) 807 return CheckAddressConstantExpression(M->getBase()); 808 return CheckAddressConstantExpressionLValue(M->getBase()); 809 } 810 case Expr::ArraySubscriptExprClass: { 811 // FIXME: Should we pedwarn for "x[0+0]" (where x is a pointer)? 812 const ArraySubscriptExpr *ASE = cast<ArraySubscriptExpr>(Init); 813 return CheckAddressConstantExpression(ASE->getBase()) || 814 CheckArithmeticConstantExpression(ASE->getIdx()); 815 } 816 case Expr::StringLiteralClass: 817 case Expr::PreDefinedExprClass: 818 return false; 819 case Expr::UnaryOperatorClass: { 820 const UnaryOperator *Exp = cast<UnaryOperator>(Init); 821 822 // C99 6.6p9 823 if (Exp->getOpcode() == UnaryOperator::Deref) 824 return CheckAddressConstantExpression(Exp->getSubExpr()); 825 826 Diag(Init->getExprLoc(), 827 diag::err_init_element_not_constant, Init->getSourceRange()); 828 return true; 829 } 830 } 831} 832 833bool Sema::CheckAddressConstantExpression(const Expr* Init) { 834 switch (Init->getStmtClass()) { 835 default: 836 Diag(Init->getExprLoc(), 837 diag::err_init_element_not_constant, Init->getSourceRange()); 838 return true; 839 case Expr::ParenExprClass: { 840 const ParenExpr* PE = cast<ParenExpr>(Init); 841 return CheckAddressConstantExpression(PE->getSubExpr()); 842 } 843 case Expr::StringLiteralClass: 844 case Expr::ObjCStringLiteralClass: 845 return false; 846 case Expr::CallExprClass: { 847 const CallExpr *CE = cast<CallExpr>(Init); 848 if (CE->isBuiltinConstantExpr()) 849 return false; 850 Diag(Init->getExprLoc(), 851 diag::err_init_element_not_constant, Init->getSourceRange()); 852 return true; 853 } 854 case Expr::UnaryOperatorClass: { 855 const UnaryOperator *Exp = cast<UnaryOperator>(Init); 856 857 // C99 6.6p9 858 if (Exp->getOpcode() == UnaryOperator::AddrOf) 859 return CheckAddressConstantExpressionLValue(Exp->getSubExpr()); 860 861 if (Exp->getOpcode() == UnaryOperator::Extension) 862 return CheckAddressConstantExpression(Exp->getSubExpr()); 863 864 Diag(Init->getExprLoc(), 865 diag::err_init_element_not_constant, Init->getSourceRange()); 866 return true; 867 } 868 case Expr::BinaryOperatorClass: { 869 // FIXME: Should we pedwarn for expressions like "a + 1 + 2"? 870 const BinaryOperator *Exp = cast<BinaryOperator>(Init); 871 872 Expr *PExp = Exp->getLHS(); 873 Expr *IExp = Exp->getRHS(); 874 if (IExp->getType()->isPointerType()) 875 std::swap(PExp, IExp); 876 877 // FIXME: Should we pedwarn if IExp isn't an integer constant expression? 878 return CheckAddressConstantExpression(PExp) || 879 CheckArithmeticConstantExpression(IExp); 880 } 881 case Expr::ImplicitCastExprClass: { 882 const Expr* SubExpr = cast<ImplicitCastExpr>(Init)->getSubExpr(); 883 884 // Check for implicit promotion 885 if (SubExpr->getType()->isFunctionType() || 886 SubExpr->getType()->isArrayType()) 887 return CheckAddressConstantExpressionLValue(SubExpr); 888 889 // Check for pointer->pointer cast 890 if (SubExpr->getType()->isPointerType()) 891 return CheckAddressConstantExpression(SubExpr); 892 893 if (SubExpr->getType()->isArithmeticType()) 894 return CheckArithmeticConstantExpression(SubExpr); 895 896 Diag(Init->getExprLoc(), 897 diag::err_init_element_not_constant, Init->getSourceRange()); 898 return true; 899 } 900 case Expr::CastExprClass: { 901 const Expr* SubExpr = cast<CastExpr>(Init)->getSubExpr(); 902 903 // Check for pointer->pointer cast 904 if (SubExpr->getType()->isPointerType()) 905 return CheckAddressConstantExpression(SubExpr); 906 907 // FIXME: Should we pedwarn for (int*)(0+0)? 908 if (SubExpr->getType()->isArithmeticType()) 909 return CheckArithmeticConstantExpression(SubExpr); 910 911 Diag(Init->getExprLoc(), 912 diag::err_init_element_not_constant, Init->getSourceRange()); 913 return true; 914 } 915 case Expr::ConditionalOperatorClass: { 916 // FIXME: Should we pedwarn here? 917 const ConditionalOperator *Exp = cast<ConditionalOperator>(Init); 918 if (!Exp->getCond()->getType()->isArithmeticType()) { 919 Diag(Init->getExprLoc(), 920 diag::err_init_element_not_constant, Init->getSourceRange()); 921 return true; 922 } 923 if (CheckArithmeticConstantExpression(Exp->getCond())) 924 return true; 925 if (Exp->getLHS() && 926 CheckAddressConstantExpression(Exp->getLHS())) 927 return true; 928 return CheckAddressConstantExpression(Exp->getRHS()); 929 } 930 case Expr::AddrLabelExprClass: 931 return false; 932 } 933} 934 935static const Expr* FindExpressionBaseAddress(const Expr* E); 936 937static const Expr* FindExpressionBaseAddressLValue(const Expr* E) { 938 switch (E->getStmtClass()) { 939 default: 940 return E; 941 case Expr::ParenExprClass: { 942 const ParenExpr* PE = cast<ParenExpr>(E); 943 return FindExpressionBaseAddressLValue(PE->getSubExpr()); 944 } 945 case Expr::MemberExprClass: { 946 const MemberExpr *M = cast<MemberExpr>(E); 947 if (M->isArrow()) 948 return FindExpressionBaseAddress(M->getBase()); 949 return FindExpressionBaseAddressLValue(M->getBase()); 950 } 951 case Expr::ArraySubscriptExprClass: { 952 const ArraySubscriptExpr *ASE = cast<ArraySubscriptExpr>(E); 953 return FindExpressionBaseAddress(ASE->getBase()); 954 } 955 case Expr::UnaryOperatorClass: { 956 const UnaryOperator *Exp = cast<UnaryOperator>(E); 957 958 if (Exp->getOpcode() == UnaryOperator::Deref) 959 return FindExpressionBaseAddress(Exp->getSubExpr()); 960 961 return E; 962 } 963 } 964} 965 966static const Expr* FindExpressionBaseAddress(const Expr* E) { 967 switch (E->getStmtClass()) { 968 default: 969 return E; 970 case Expr::ParenExprClass: { 971 const ParenExpr* PE = cast<ParenExpr>(E); 972 return FindExpressionBaseAddress(PE->getSubExpr()); 973 } 974 case Expr::UnaryOperatorClass: { 975 const UnaryOperator *Exp = cast<UnaryOperator>(E); 976 977 // C99 6.6p9 978 if (Exp->getOpcode() == UnaryOperator::AddrOf) 979 return FindExpressionBaseAddressLValue(Exp->getSubExpr()); 980 981 if (Exp->getOpcode() == UnaryOperator::Extension) 982 return FindExpressionBaseAddress(Exp->getSubExpr()); 983 984 return E; 985 } 986 case Expr::BinaryOperatorClass: { 987 const BinaryOperator *Exp = cast<BinaryOperator>(E); 988 989 Expr *PExp = Exp->getLHS(); 990 Expr *IExp = Exp->getRHS(); 991 if (IExp->getType()->isPointerType()) 992 std::swap(PExp, IExp); 993 994 return FindExpressionBaseAddress(PExp); 995 } 996 case Expr::ImplicitCastExprClass: { 997 const Expr* SubExpr = cast<ImplicitCastExpr>(E)->getSubExpr(); 998 999 // Check for implicit promotion 1000 if (SubExpr->getType()->isFunctionType() || 1001 SubExpr->getType()->isArrayType()) 1002 return FindExpressionBaseAddressLValue(SubExpr); 1003 1004 // Check for pointer->pointer cast 1005 if (SubExpr->getType()->isPointerType()) 1006 return FindExpressionBaseAddress(SubExpr); 1007 1008 // We assume that we have an arithmetic expression here; 1009 // if we don't, we'll figure it out later 1010 return 0; 1011 } 1012 case Expr::CastExprClass: { 1013 const Expr* SubExpr = cast<CastExpr>(E)->getSubExpr(); 1014 1015 // Check for pointer->pointer cast 1016 if (SubExpr->getType()->isPointerType()) 1017 return FindExpressionBaseAddress(SubExpr); 1018 1019 // We assume that we have an arithmetic expression here; 1020 // if we don't, we'll figure it out later 1021 return 0; 1022 } 1023 } 1024} 1025 1026bool Sema::CheckArithmeticConstantExpression(const Expr* Init) { 1027 switch (Init->getStmtClass()) { 1028 default: 1029 Diag(Init->getExprLoc(), 1030 diag::err_init_element_not_constant, Init->getSourceRange()); 1031 return true; 1032 case Expr::ParenExprClass: { 1033 const ParenExpr* PE = cast<ParenExpr>(Init); 1034 return CheckArithmeticConstantExpression(PE->getSubExpr()); 1035 } 1036 case Expr::FloatingLiteralClass: 1037 case Expr::IntegerLiteralClass: 1038 case Expr::CharacterLiteralClass: 1039 case Expr::ImaginaryLiteralClass: 1040 case Expr::TypesCompatibleExprClass: 1041 case Expr::CXXBoolLiteralExprClass: 1042 return false; 1043 case Expr::CallExprClass: { 1044 const CallExpr *CE = cast<CallExpr>(Init); 1045 if (CE->isBuiltinConstantExpr()) 1046 return false; 1047 Diag(Init->getExprLoc(), 1048 diag::err_init_element_not_constant, Init->getSourceRange()); 1049 return true; 1050 } 1051 case Expr::DeclRefExprClass: { 1052 const Decl *D = cast<DeclRefExpr>(Init)->getDecl(); 1053 if (isa<EnumConstantDecl>(D)) 1054 return false; 1055 Diag(Init->getExprLoc(), 1056 diag::err_init_element_not_constant, Init->getSourceRange()); 1057 return true; 1058 } 1059 case Expr::CompoundLiteralExprClass: 1060 // Allow "(vector type){2,4}"; normal C constraints don't allow this, 1061 // but vectors are allowed to be magic. 1062 if (Init->getType()->isVectorType()) 1063 return false; 1064 Diag(Init->getExprLoc(), 1065 diag::err_init_element_not_constant, Init->getSourceRange()); 1066 return true; 1067 case Expr::UnaryOperatorClass: { 1068 const UnaryOperator *Exp = cast<UnaryOperator>(Init); 1069 1070 switch (Exp->getOpcode()) { 1071 // Address, indirect, pre/post inc/dec, etc are not valid constant exprs. 1072 // See C99 6.6p3. 1073 default: 1074 Diag(Init->getExprLoc(), 1075 diag::err_init_element_not_constant, Init->getSourceRange()); 1076 return true; 1077 case UnaryOperator::SizeOf: 1078 case UnaryOperator::AlignOf: 1079 case UnaryOperator::OffsetOf: 1080 // sizeof(E) is a constantexpr if and only if E is not evaluted. 1081 // See C99 6.5.3.4p2 and 6.6p3. 1082 if (Exp->getSubExpr()->getType()->isConstantSizeType()) 1083 return false; 1084 Diag(Init->getExprLoc(), 1085 diag::err_init_element_not_constant, Init->getSourceRange()); 1086 return true; 1087 case UnaryOperator::Extension: 1088 case UnaryOperator::LNot: 1089 case UnaryOperator::Plus: 1090 case UnaryOperator::Minus: 1091 case UnaryOperator::Not: 1092 return CheckArithmeticConstantExpression(Exp->getSubExpr()); 1093 } 1094 } 1095 case Expr::SizeOfAlignOfTypeExprClass: { 1096 const SizeOfAlignOfTypeExpr *Exp = cast<SizeOfAlignOfTypeExpr>(Init); 1097 // Special check for void types, which are allowed as an extension 1098 if (Exp->getArgumentType()->isVoidType()) 1099 return false; 1100 // alignof always evaluates to a constant. 1101 // FIXME: is sizeof(int[3.0]) a constant expression? 1102 if (Exp->isSizeOf() && !Exp->getArgumentType()->isConstantSizeType()) { 1103 Diag(Init->getExprLoc(), 1104 diag::err_init_element_not_constant, Init->getSourceRange()); 1105 return true; 1106 } 1107 return false; 1108 } 1109 case Expr::BinaryOperatorClass: { 1110 const BinaryOperator *Exp = cast<BinaryOperator>(Init); 1111 1112 if (Exp->getLHS()->getType()->isArithmeticType() && 1113 Exp->getRHS()->getType()->isArithmeticType()) { 1114 return CheckArithmeticConstantExpression(Exp->getLHS()) || 1115 CheckArithmeticConstantExpression(Exp->getRHS()); 1116 } 1117 1118 if (Exp->getLHS()->getType()->isPointerType() && 1119 Exp->getRHS()->getType()->isPointerType()) { 1120 const Expr* LHSBase = FindExpressionBaseAddress(Exp->getLHS()); 1121 const Expr* RHSBase = FindExpressionBaseAddress(Exp->getRHS()); 1122 1123 // Only allow a null (constant integer) base; we could 1124 // allow some additional cases if necessary, but this 1125 // is sufficient to cover offsetof-like constructs. 1126 if (!LHSBase && !RHSBase) { 1127 return CheckAddressConstantExpression(Exp->getLHS()) || 1128 CheckAddressConstantExpression(Exp->getRHS()); 1129 } 1130 } 1131 1132 Diag(Init->getExprLoc(), 1133 diag::err_init_element_not_constant, Init->getSourceRange()); 1134 return true; 1135 } 1136 case Expr::ImplicitCastExprClass: 1137 case Expr::CastExprClass: { 1138 const Expr *SubExpr; 1139 if (const CastExpr *C = dyn_cast<CastExpr>(Init)) { 1140 SubExpr = C->getSubExpr(); 1141 } else { 1142 SubExpr = cast<ImplicitCastExpr>(Init)->getSubExpr(); 1143 } 1144 1145 if (SubExpr->getType()->isArithmeticType()) 1146 return CheckArithmeticConstantExpression(SubExpr); 1147 1148 Diag(Init->getExprLoc(), 1149 diag::err_init_element_not_constant, Init->getSourceRange()); 1150 return true; 1151 } 1152 case Expr::ConditionalOperatorClass: { 1153 const ConditionalOperator *Exp = cast<ConditionalOperator>(Init); 1154 if (CheckArithmeticConstantExpression(Exp->getCond())) 1155 return true; 1156 if (Exp->getLHS() && 1157 CheckArithmeticConstantExpression(Exp->getLHS())) 1158 return true; 1159 return CheckArithmeticConstantExpression(Exp->getRHS()); 1160 } 1161 } 1162} 1163 1164bool Sema::CheckForConstantInitializer(Expr *Init, QualType DclT) { 1165 // Look through CXXDefaultArgExprs; they have no meaning in this context. 1166 if (CXXDefaultArgExpr* DAE = dyn_cast<CXXDefaultArgExpr>(Init)) 1167 return CheckForConstantInitializer(DAE->getExpr(), DclT); 1168 1169 if (Init->getType()->isReferenceType()) { 1170 // FIXME: Work out how the heck reference types work 1171 return false; 1172#if 0 1173 // A reference is constant if the address of the expression 1174 // is constant 1175 // We look through initlists here to simplify 1176 // CheckAddressConstantExpressionLValue. 1177 if (InitListExpr *Exp = dyn_cast<InitListExpr>(Init)) { 1178 assert(Exp->getNumInits() > 0 && 1179 "Refernce initializer cannot be empty"); 1180 Init = Exp->getInit(0); 1181 } 1182 return CheckAddressConstantExpressionLValue(Init); 1183#endif 1184 } 1185 1186 if (InitListExpr *Exp = dyn_cast<InitListExpr>(Init)) { 1187 unsigned numInits = Exp->getNumInits(); 1188 for (unsigned i = 0; i < numInits; i++) { 1189 // FIXME: Need to get the type of the declaration for C++, 1190 // because it could be a reference? 1191 if (CheckForConstantInitializer(Exp->getInit(i), 1192 Exp->getInit(i)->getType())) 1193 return true; 1194 } 1195 return false; 1196 } 1197 1198 if (Init->isNullPointerConstant(Context)) 1199 return false; 1200 if (Init->getType()->isArithmeticType()) { 1201 QualType InitTy = Init->getType().getCanonicalType().getUnqualifiedType(); 1202 if (InitTy == Context.BoolTy) { 1203 // Special handling for pointers implicitly cast to bool; 1204 // (e.g. "_Bool rr = &rr;"). This is only legal at the top level. 1205 if (ImplicitCastExpr* ICE = dyn_cast<ImplicitCastExpr>(Init)) { 1206 Expr* SubE = ICE->getSubExpr(); 1207 if (SubE->getType()->isPointerType() || 1208 SubE->getType()->isArrayType() || 1209 SubE->getType()->isFunctionType()) { 1210 return CheckAddressConstantExpression(Init); 1211 } 1212 } 1213 } else if (InitTy->isIntegralType()) { 1214 Expr* SubE = 0; 1215 if (ImplicitCastExpr* ICE = dyn_cast<ImplicitCastExpr>(Init)) 1216 SubE = ICE->getSubExpr(); 1217 else if (CastExpr* CE = dyn_cast<CastExpr>(Init)) 1218 SubE = CE->getSubExpr(); 1219 // Special check for pointer cast to int; we allow as an extension 1220 // an address constant cast to an integer if the integer 1221 // is of an appropriate width (this sort of code is apparently used 1222 // in some places). 1223 // FIXME: Add pedwarn? 1224 // FIXME: Don't allow bitfields here! Need the FieldDecl for that. 1225 if (SubE && (SubE->getType()->isPointerType() || 1226 SubE->getType()->isArrayType() || 1227 SubE->getType()->isFunctionType())) { 1228 unsigned IntWidth = Context.getTypeSize(Init->getType()); 1229 unsigned PointerWidth = Context.getTypeSize(Context.VoidPtrTy); 1230 if (IntWidth >= PointerWidth) 1231 return CheckAddressConstantExpression(Init); 1232 } 1233 } 1234 1235 return CheckArithmeticConstantExpression(Init); 1236 } 1237 1238 if (Init->getType()->isPointerType()) 1239 return CheckAddressConstantExpression(Init); 1240 1241 // An array type at the top level that isn't an init-list must 1242 // be a string literal 1243 if (Init->getType()->isArrayType()) 1244 return false; 1245 1246 Diag(Init->getExprLoc(), diag::err_init_element_not_constant, 1247 Init->getSourceRange()); 1248 return true; 1249} 1250 1251void Sema::AddInitializerToDecl(DeclTy *dcl, ExprTy *init) { 1252 Decl *RealDecl = static_cast<Decl *>(dcl); 1253 Expr *Init = static_cast<Expr *>(init); 1254 assert(Init && "missing initializer"); 1255 1256 // If there is no declaration, there was an error parsing it. Just ignore 1257 // the initializer. 1258 if (RealDecl == 0) { 1259 delete Init; 1260 return; 1261 } 1262 1263 VarDecl *VDecl = dyn_cast<VarDecl>(RealDecl); 1264 if (!VDecl) { 1265 Diag(dyn_cast<ScopedDecl>(RealDecl)->getLocation(), 1266 diag::err_illegal_initializer); 1267 RealDecl->setInvalidDecl(); 1268 return; 1269 } 1270 // Get the decls type and save a reference for later, since 1271 // CheckInitializerTypes may change it. 1272 QualType DclT = VDecl->getType(), SavT = DclT; 1273 if (VDecl->isBlockVarDecl()) { 1274 VarDecl::StorageClass SC = VDecl->getStorageClass(); 1275 if (SC == VarDecl::Extern) { // C99 6.7.8p5 1276 Diag(VDecl->getLocation(), diag::err_block_extern_cant_init); 1277 VDecl->setInvalidDecl(); 1278 } else if (!VDecl->isInvalidDecl()) { 1279 if (CheckInitializerTypes(Init, DclT)) 1280 VDecl->setInvalidDecl(); 1281 if (SC == VarDecl::Static) // C99 6.7.8p4. 1282 CheckForConstantInitializer(Init, DclT); 1283 } 1284 } else if (VDecl->isFileVarDecl()) { 1285 if (VDecl->getStorageClass() == VarDecl::Extern) 1286 Diag(VDecl->getLocation(), diag::warn_extern_init); 1287 if (!VDecl->isInvalidDecl()) 1288 if (CheckInitializerTypes(Init, DclT)) 1289 VDecl->setInvalidDecl(); 1290 1291 // C99 6.7.8p4. All file scoped initializers need to be constant. 1292 CheckForConstantInitializer(Init, DclT); 1293 } 1294 // If the type changed, it means we had an incomplete type that was 1295 // completed by the initializer. For example: 1296 // int ary[] = { 1, 3, 5 }; 1297 // "ary" transitions from a VariableArrayType to a ConstantArrayType. 1298 if (!VDecl->isInvalidDecl() && (DclT != SavT)) { 1299 VDecl->setType(DclT); 1300 Init->setType(DclT); 1301 } 1302 1303 // Attach the initializer to the decl. 1304 VDecl->setInit(Init); 1305 return; 1306} 1307 1308/// The declarators are chained together backwards, reverse the list. 1309Sema::DeclTy *Sema::FinalizeDeclaratorGroup(Scope *S, DeclTy *group) { 1310 // Often we have single declarators, handle them quickly. 1311 Decl *GroupDecl = static_cast<Decl*>(group); 1312 if (GroupDecl == 0) 1313 return 0; 1314 1315 ScopedDecl *Group = dyn_cast<ScopedDecl>(GroupDecl); 1316 ScopedDecl *NewGroup = 0; 1317 if (Group->getNextDeclarator() == 0) 1318 NewGroup = Group; 1319 else { // reverse the list. 1320 while (Group) { 1321 ScopedDecl *Next = Group->getNextDeclarator(); 1322 Group->setNextDeclarator(NewGroup); 1323 NewGroup = Group; 1324 Group = Next; 1325 } 1326 } 1327 // Perform semantic analysis that depends on having fully processed both 1328 // the declarator and initializer. 1329 for (ScopedDecl *ID = NewGroup; ID; ID = ID->getNextDeclarator()) { 1330 VarDecl *IDecl = dyn_cast<VarDecl>(ID); 1331 if (!IDecl) 1332 continue; 1333 QualType T = IDecl->getType(); 1334 1335 // C99 6.7.5.2p2: If an identifier is declared to be an object with 1336 // static storage duration, it shall not have a variable length array. 1337 if ((IDecl->isFileVarDecl() || IDecl->isBlockVarDecl()) && 1338 IDecl->getStorageClass() == VarDecl::Static) { 1339 if (T->getAsVariableArrayType()) { 1340 Diag(IDecl->getLocation(), diag::err_typecheck_illegal_vla); 1341 IDecl->setInvalidDecl(); 1342 } 1343 } 1344 // Block scope. C99 6.7p7: If an identifier for an object is declared with 1345 // no linkage (C99 6.2.2p6), the type for the object shall be complete... 1346 if (IDecl->isBlockVarDecl() && 1347 IDecl->getStorageClass() != VarDecl::Extern) { 1348 if (T->isIncompleteType() && !IDecl->isInvalidDecl()) { 1349 Diag(IDecl->getLocation(), diag::err_typecheck_decl_incomplete_type, 1350 T.getAsString()); 1351 IDecl->setInvalidDecl(); 1352 } 1353 } 1354 // File scope. C99 6.9.2p2: A declaration of an identifier for and 1355 // object that has file scope without an initializer, and without a 1356 // storage-class specifier or with the storage-class specifier "static", 1357 // constitutes a tentative definition. Note: A tentative definition with 1358 // external linkage is valid (C99 6.2.2p5). 1359 if (IDecl && !IDecl->getInit() && 1360 (IDecl->getStorageClass() == VarDecl::Static || 1361 IDecl->getStorageClass() == VarDecl::None)) { 1362 if (T->isIncompleteArrayType()) { 1363 // C99 6.9.2 (p2, p5): Implicit initialization causes an incomplete 1364 // array to be completed. Don't issue a diagnostic. 1365 } else if (T->isIncompleteType() && !IDecl->isInvalidDecl()) { 1366 // C99 6.9.2p3: If the declaration of an identifier for an object is 1367 // a tentative definition and has internal linkage (C99 6.2.2p3), the 1368 // declared type shall not be an incomplete type. 1369 Diag(IDecl->getLocation(), diag::err_typecheck_decl_incomplete_type, 1370 T.getAsString()); 1371 IDecl->setInvalidDecl(); 1372 } 1373 } 1374 } 1375 return NewGroup; 1376} 1377 1378/// ActOnParamDeclarator - Called from Parser::ParseFunctionDeclarator() 1379/// to introduce parameters into function prototype scope. 1380Sema::DeclTy * 1381Sema::ActOnParamDeclarator(Scope *S, Declarator &D) { 1382 const DeclSpec &DS = D.getDeclSpec(); 1383 1384 // Verify C99 6.7.5.3p2: The only SCS allowed is 'register'. 1385 if (DS.getStorageClassSpec() != DeclSpec::SCS_unspecified && 1386 DS.getStorageClassSpec() != DeclSpec::SCS_register) { 1387 Diag(DS.getStorageClassSpecLoc(), 1388 diag::err_invalid_storage_class_in_func_decl); 1389 D.getMutableDeclSpec().ClearStorageClassSpecs(); 1390 } 1391 if (DS.isThreadSpecified()) { 1392 Diag(DS.getThreadSpecLoc(), 1393 diag::err_invalid_storage_class_in_func_decl); 1394 D.getMutableDeclSpec().ClearStorageClassSpecs(); 1395 } 1396 1397 // Check that there are no default arguments inside the type of this 1398 // parameter (C++ only). 1399 if (getLangOptions().CPlusPlus) 1400 CheckExtraCXXDefaultArguments(D); 1401 1402 // In this context, we *do not* check D.getInvalidType(). If the declarator 1403 // type was invalid, GetTypeForDeclarator() still returns a "valid" type, 1404 // though it will not reflect the user specified type. 1405 QualType parmDeclType = GetTypeForDeclarator(D, S); 1406 1407 assert(!parmDeclType.isNull() && "GetTypeForDeclarator() returned null type"); 1408 1409 // TODO: CHECK FOR CONFLICTS, multiple decls with same name in one scope. 1410 // Can this happen for params? We already checked that they don't conflict 1411 // among each other. Here they can only shadow globals, which is ok. 1412 IdentifierInfo *II = D.getIdentifier(); 1413 if (Decl *PrevDecl = LookupDecl(II, Decl::IDNS_Ordinary, S)) { 1414 if (S->isDeclScope(PrevDecl)) { 1415 Diag(D.getIdentifierLoc(), diag::err_param_redefinition, 1416 dyn_cast<NamedDecl>(PrevDecl)->getName()); 1417 1418 // Recover by removing the name 1419 II = 0; 1420 D.SetIdentifier(0, D.getIdentifierLoc()); 1421 } 1422 } 1423 1424 // Perform the default function/array conversion (C99 6.7.5.3p[7,8]). 1425 // Doing the promotion here has a win and a loss. The win is the type for 1426 // both Decl's and DeclRefExpr's will match (a convenient invariant for the 1427 // code generator). The loss is the orginal type isn't preserved. For example: 1428 // 1429 // void func(int parmvardecl[5]) { // convert "int [5]" to "int *" 1430 // int blockvardecl[5]; 1431 // sizeof(parmvardecl); // size == 4 1432 // sizeof(blockvardecl); // size == 20 1433 // } 1434 // 1435 // For expressions, all implicit conversions are captured using the 1436 // ImplicitCastExpr AST node (we have no such mechanism for Decl's). 1437 // 1438 // FIXME: If a source translation tool needs to see the original type, then 1439 // we need to consider storing both types (in ParmVarDecl)... 1440 // 1441 if (parmDeclType->isArrayType()) { 1442 // int x[restrict 4] -> int *restrict 1443 parmDeclType = Context.getArrayDecayedType(parmDeclType); 1444 } else if (parmDeclType->isFunctionType()) 1445 parmDeclType = Context.getPointerType(parmDeclType); 1446 1447 ParmVarDecl *New = ParmVarDecl::Create(Context, CurContext, 1448 D.getIdentifierLoc(), II, 1449 parmDeclType, VarDecl::None, 1450 0, 0); 1451 1452 if (D.getInvalidType()) 1453 New->setInvalidDecl(); 1454 1455 if (II) 1456 PushOnScopeChains(New, S); 1457 1458 HandleDeclAttributes(New, D.getDeclSpec().getAttributes(), 1459 D.getAttributes()); 1460 return New; 1461 1462} 1463 1464Sema::DeclTy *Sema::ActOnStartOfFunctionDef(Scope *FnBodyScope, Declarator &D) { 1465 assert(CurFunctionDecl == 0 && "Function parsing confused"); 1466 assert(D.getTypeObject(0).Kind == DeclaratorChunk::Function && 1467 "Not a function declarator!"); 1468 DeclaratorChunk::FunctionTypeInfo &FTI = D.getTypeObject(0).Fun; 1469 1470 // Verify 6.9.1p6: 'every identifier in the identifier list shall be declared' 1471 // for a K&R function. 1472 if (!FTI.hasPrototype) { 1473 for (unsigned i = 0, e = FTI.NumArgs; i != e; ++i) { 1474 if (FTI.ArgInfo[i].Param == 0) { 1475 Diag(FTI.ArgInfo[i].IdentLoc, diag::ext_param_not_declared, 1476 FTI.ArgInfo[i].Ident->getName()); 1477 // Implicitly declare the argument as type 'int' for lack of a better 1478 // type. 1479 DeclSpec DS; 1480 const char* PrevSpec; // unused 1481 DS.SetTypeSpecType(DeclSpec::TST_int, FTI.ArgInfo[i].IdentLoc, 1482 PrevSpec); 1483 Declarator ParamD(DS, Declarator::KNRTypeListContext); 1484 ParamD.SetIdentifier(FTI.ArgInfo[i].Ident, FTI.ArgInfo[i].IdentLoc); 1485 FTI.ArgInfo[i].Param = ActOnParamDeclarator(FnBodyScope, ParamD); 1486 } 1487 } 1488 1489 // Since this is a function definition, act as though we have information 1490 // about the arguments. 1491 if (FTI.NumArgs) 1492 FTI.hasPrototype = true; 1493 } else { 1494 // FIXME: Diagnose arguments without names in C. 1495 } 1496 1497 Scope *GlobalScope = FnBodyScope->getParent(); 1498 1499 // See if this is a redefinition. 1500 Decl *PrevDcl = LookupDecl(D.getIdentifier(), Decl::IDNS_Ordinary, 1501 GlobalScope); 1502 if (PrevDcl && IdResolver.isDeclInScope(PrevDcl, CurContext)) { 1503 if (FunctionDecl *FD = dyn_cast<FunctionDecl>(PrevDcl)) { 1504 const FunctionDecl *Definition; 1505 if (FD->getBody(Definition)) { 1506 Diag(D.getIdentifierLoc(), diag::err_redefinition, 1507 D.getIdentifier()->getName()); 1508 Diag(Definition->getLocation(), diag::err_previous_definition); 1509 } 1510 } 1511 } 1512 Decl *decl = static_cast<Decl*>(ActOnDeclarator(GlobalScope, D, 0)); 1513 FunctionDecl *FD = cast<FunctionDecl>(decl); 1514 CurFunctionDecl = FD; 1515 PushDeclContext(FD); 1516 1517 // Check the validity of our function parameters 1518 CheckParmsForFunctionDef(FD); 1519 1520 // Introduce our parameters into the function scope 1521 for (unsigned p = 0, NumParams = FD->getNumParams(); p < NumParams; ++p) { 1522 ParmVarDecl *Param = FD->getParamDecl(p); 1523 // If this has an identifier, add it to the scope stack. 1524 if (Param->getIdentifier()) 1525 PushOnScopeChains(Param, FnBodyScope); 1526 } 1527 1528 return FD; 1529} 1530 1531Sema::DeclTy *Sema::ActOnFinishFunctionBody(DeclTy *D, StmtTy *Body) { 1532 Decl *dcl = static_cast<Decl *>(D); 1533 if (FunctionDecl *FD = dyn_cast<FunctionDecl>(dcl)) { 1534 FD->setBody((Stmt*)Body); 1535 assert(FD == CurFunctionDecl && "Function parsing confused"); 1536 CurFunctionDecl = 0; 1537 } else if (ObjCMethodDecl *MD = dyn_cast<ObjCMethodDecl>(dcl)) { 1538 MD->setBody((Stmt*)Body); 1539 CurMethodDecl = 0; 1540 } 1541 PopDeclContext(); 1542 // Verify and clean out per-function state. 1543 1544 // Check goto/label use. 1545 for (llvm::DenseMap<IdentifierInfo*, LabelStmt*>::iterator 1546 I = LabelMap.begin(), E = LabelMap.end(); I != E; ++I) { 1547 // Verify that we have no forward references left. If so, there was a goto 1548 // or address of a label taken, but no definition of it. Label fwd 1549 // definitions are indicated with a null substmt. 1550 if (I->second->getSubStmt() == 0) { 1551 LabelStmt *L = I->second; 1552 // Emit error. 1553 Diag(L->getIdentLoc(), diag::err_undeclared_label_use, L->getName()); 1554 1555 // At this point, we have gotos that use the bogus label. Stitch it into 1556 // the function body so that they aren't leaked and that the AST is well 1557 // formed. 1558 if (Body) { 1559 L->setSubStmt(new NullStmt(L->getIdentLoc())); 1560 cast<CompoundStmt>((Stmt*)Body)->push_back(L); 1561 } else { 1562 // The whole function wasn't parsed correctly, just delete this. 1563 delete L; 1564 } 1565 } 1566 } 1567 LabelMap.clear(); 1568 1569 return D; 1570} 1571 1572/// ImplicitlyDefineFunction - An undeclared identifier was used in a function 1573/// call, forming a call to an implicitly defined function (per C99 6.5.1p2). 1574ScopedDecl *Sema::ImplicitlyDefineFunction(SourceLocation Loc, 1575 IdentifierInfo &II, Scope *S) { 1576 // Extension in C99. Legal in C90, but warn about it. 1577 if (getLangOptions().C99) 1578 Diag(Loc, diag::ext_implicit_function_decl, II.getName()); 1579 else 1580 Diag(Loc, diag::warn_implicit_function_decl, II.getName()); 1581 1582 // FIXME: handle stuff like: 1583 // void foo() { extern float X(); } 1584 // void bar() { X(); } <-- implicit decl for X in another scope. 1585 1586 // Set a Declarator for the implicit definition: int foo(); 1587 const char *Dummy; 1588 DeclSpec DS; 1589 bool Error = DS.SetTypeSpecType(DeclSpec::TST_int, Loc, Dummy); 1590 Error = Error; // Silence warning. 1591 assert(!Error && "Error setting up implicit decl!"); 1592 Declarator D(DS, Declarator::BlockContext); 1593 D.AddTypeInfo(DeclaratorChunk::getFunction(false, false, 0, 0, Loc)); 1594 D.SetIdentifier(&II, Loc); 1595 1596 // Insert this function into translation-unit scope. 1597 1598 DeclContext *PrevDC = CurContext; 1599 CurContext = Context.getTranslationUnitDecl(); 1600 1601 FunctionDecl *FD = 1602 dyn_cast<FunctionDecl>(static_cast<Decl*>(ActOnDeclarator(TUScope, D, 0))); 1603 FD->setImplicit(); 1604 1605 CurContext = PrevDC; 1606 1607 return FD; 1608} 1609 1610 1611TypedefDecl *Sema::ParseTypedefDecl(Scope *S, Declarator &D, QualType T, 1612 ScopedDecl *LastDeclarator) { 1613 assert(D.getIdentifier() && "Wrong callback for declspec without declarator"); 1614 assert(!T.isNull() && "GetTypeForDeclarator() returned null type"); 1615 1616 // Scope manipulation handled by caller. 1617 TypedefDecl *NewTD = TypedefDecl::Create(Context, CurContext, 1618 D.getIdentifierLoc(), 1619 D.getIdentifier(), 1620 T, LastDeclarator); 1621 if (D.getInvalidType()) 1622 NewTD->setInvalidDecl(); 1623 return NewTD; 1624} 1625 1626/// ActOnTag - This is invoked when we see 'struct foo' or 'struct {'. In the 1627/// former case, Name will be non-null. In the later case, Name will be null. 1628/// TagType indicates what kind of tag this is. TK indicates whether this is a 1629/// reference/declaration/definition of a tag. 1630Sema::DeclTy *Sema::ActOnTag(Scope *S, unsigned TagType, TagKind TK, 1631 SourceLocation KWLoc, IdentifierInfo *Name, 1632 SourceLocation NameLoc, AttributeList *Attr) { 1633 // If this is a use of an existing tag, it must have a name. 1634 assert((Name != 0 || TK == TK_Definition) && 1635 "Nameless record must be a definition!"); 1636 1637 TagDecl::TagKind Kind; 1638 switch (TagType) { 1639 default: assert(0 && "Unknown tag type!"); 1640 case DeclSpec::TST_struct: Kind = TagDecl::TK_struct; break; 1641 case DeclSpec::TST_union: Kind = TagDecl::TK_union; break; 1642 case DeclSpec::TST_class: Kind = TagDecl::TK_class; break; 1643 case DeclSpec::TST_enum: Kind = TagDecl::TK_enum; break; 1644 } 1645 1646 // If this is a named struct, check to see if there was a previous forward 1647 // declaration or definition. 1648 // Use ScopedDecl instead of TagDecl, because a NamespaceDecl may come up. 1649 if (ScopedDecl *PrevDecl = 1650 dyn_cast_or_null<ScopedDecl>(LookupDecl(Name, Decl::IDNS_Tag, S))) { 1651 1652 assert((isa<TagDecl>(PrevDecl) || isa<NamespaceDecl>(PrevDecl)) && 1653 "unexpected Decl type"); 1654 if (TagDecl *PrevTagDecl = dyn_cast<TagDecl>(PrevDecl)) { 1655 // If this is a use of a previous tag, or if the tag is already declared in 1656 // the same scope (so that the definition/declaration completes or 1657 // rementions the tag), reuse the decl. 1658 if (TK == TK_Reference || 1659 IdResolver.isDeclInScope(PrevDecl, CurContext, S)) { 1660 // Make sure that this wasn't declared as an enum and now used as a struct 1661 // or something similar. 1662 if (PrevTagDecl->getTagKind() != Kind) { 1663 Diag(KWLoc, diag::err_use_with_wrong_tag, Name->getName()); 1664 Diag(PrevDecl->getLocation(), diag::err_previous_use); 1665 } 1666 1667 // If this is a use or a forward declaration, we're good. 1668 if (TK != TK_Definition) 1669 return PrevDecl; 1670 1671 // Diagnose attempts to redefine a tag. 1672 if (PrevTagDecl->isDefinition()) { 1673 Diag(NameLoc, diag::err_redefinition, Name->getName()); 1674 Diag(PrevDecl->getLocation(), diag::err_previous_definition); 1675 // If this is a redefinition, recover by making this struct be 1676 // anonymous, which will make any later references get the previous 1677 // definition. 1678 Name = 0; 1679 } else { 1680 // Okay, this is definition of a previously declared or referenced tag. 1681 // Move the location of the decl to be the definition site. 1682 PrevDecl->setLocation(NameLoc); 1683 return PrevDecl; 1684 } 1685 } 1686 // If we get here, this is a definition of a new struct type in a nested 1687 // scope, e.g. "struct foo; void bar() { struct foo; }", just create a new 1688 // type. 1689 } else { 1690 // The tag name clashes with a namespace name, issue an error and recover 1691 // by making this tag be anonymous. 1692 Diag(NameLoc, diag::err_redefinition_different_kind, Name->getName()); 1693 Diag(PrevDecl->getLocation(), diag::err_previous_definition); 1694 Name = 0; 1695 } 1696 } 1697 1698 // If there is an identifier, use the location of the identifier as the 1699 // location of the decl, otherwise use the location of the struct/union 1700 // keyword. 1701 SourceLocation Loc = NameLoc.isValid() ? NameLoc : KWLoc; 1702 1703 // Otherwise, if this is the first time we've seen this tag, create the decl. 1704 TagDecl *New; 1705 if (Kind == TagDecl::TK_enum) { 1706 // FIXME: Tag decls should be chained to any simultaneous vardecls, e.g.: 1707 // enum X { A, B, C } D; D should chain to X. 1708 New = EnumDecl::Create(Context, CurContext, Loc, Name, 0); 1709 // If this is an undefined enum, warn. 1710 if (TK != TK_Definition) Diag(Loc, diag::ext_forward_ref_enum); 1711 } else { 1712 // struct/union/class 1713 1714 // FIXME: Tag decls should be chained to any simultaneous vardecls, e.g.: 1715 // struct X { int A; } D; D should chain to X. 1716 New = RecordDecl::Create(Context, Kind, CurContext, Loc, Name, 0); 1717 } 1718 1719 // If this has an identifier, add it to the scope stack. 1720 if (Name) { 1721 // The scope passed in may not be a decl scope. Zip up the scope tree until 1722 // we find one that is. 1723 while ((S->getFlags() & Scope::DeclScope) == 0) 1724 S = S->getParent(); 1725 1726 // Add it to the decl chain. 1727 PushOnScopeChains(New, S); 1728 } 1729 1730 HandleDeclAttributes(New, Attr, 0); 1731 return New; 1732} 1733 1734/// Collect the instance variables declared in an Objective-C object. Used in 1735/// the creation of structures from objects using the @defs directive. 1736static void CollectIvars(ObjCInterfaceDecl *Class, 1737 llvm::SmallVector<Sema::DeclTy*, 16> &ivars) { 1738 if (Class->getSuperClass()) 1739 CollectIvars(Class->getSuperClass(), ivars); 1740 ivars.append(Class->ivar_begin(), Class->ivar_end()); 1741} 1742 1743/// Called whenever @defs(ClassName) is encountered in the source. Inserts the 1744/// instance variables of ClassName into Decls. 1745void Sema::ActOnDefs(Scope *S, SourceLocation DeclStart, 1746 IdentifierInfo *ClassName, 1747 llvm::SmallVector<DeclTy*, 16> &Decls) { 1748 // Check that ClassName is a valid class 1749 ObjCInterfaceDecl *Class = getObjCInterfaceDecl(ClassName); 1750 if (!Class) { 1751 Diag(DeclStart, diag::err_undef_interface, ClassName->getName()); 1752 return; 1753 } 1754 // Collect the instance variables 1755 CollectIvars(Class, Decls); 1756} 1757 1758 1759static bool CalcFakeICEVal(const Expr* Expr, 1760 llvm::APSInt& Result, 1761 ASTContext& Context) { 1762 // Calculate the value of an expression that has a calculatable 1763 // value, but isn't an ICE. Currently, this only supports 1764 // a very narrow set of extensions, but it can be expanded if needed. 1765 if (const ParenExpr *PE = dyn_cast<ParenExpr>(Expr)) 1766 return CalcFakeICEVal(PE->getSubExpr(), Result, Context); 1767 1768 if (const CastExpr *CE = dyn_cast<CastExpr>(Expr)) { 1769 QualType CETy = CE->getType(); 1770 if ((CETy->isIntegralType() && !CETy->isBooleanType()) || 1771 CETy->isPointerType()) { 1772 if (CalcFakeICEVal(CE->getSubExpr(), Result, Context)) { 1773 Result.extOrTrunc(Context.getTypeSize(CETy)); 1774 // FIXME: This assumes pointers are signed. 1775 Result.setIsSigned(CETy->isSignedIntegerType() || 1776 CETy->isPointerType()); 1777 return true; 1778 } 1779 } 1780 } 1781 1782 if (Expr->getType()->isIntegralType()) 1783 return Expr->isIntegerConstantExpr(Result, Context); 1784 1785 return false; 1786} 1787 1788QualType Sema::TryFixInvalidVariablyModifiedType(QualType T) { 1789 // This method tries to turn a variable array into a constant 1790 // array even when the size isn't an ICE. This is necessary 1791 // for compatibility with code that depends on gcc's buggy 1792 // constant expression folding, like struct {char x[(int)(char*)2];} 1793 if (const VariableArrayType* VLATy = dyn_cast<VariableArrayType>(T)) { 1794 llvm::APSInt Result(32); 1795 if (VLATy->getSizeExpr() && 1796 CalcFakeICEVal(VLATy->getSizeExpr(), Result, Context) && 1797 Result > llvm::APSInt(Result.getBitWidth(), Result.isUnsigned())) { 1798 return Context.getConstantArrayType(VLATy->getElementType(), 1799 Result, ArrayType::Normal, 0); 1800 } 1801 } 1802 return QualType(); 1803} 1804 1805/// ActOnField - Each field of a struct/union/class is passed into this in order 1806/// to create a FieldDecl object for it. 1807Sema::DeclTy *Sema::ActOnField(Scope *S, 1808 SourceLocation DeclStart, 1809 Declarator &D, ExprTy *BitfieldWidth) { 1810 IdentifierInfo *II = D.getIdentifier(); 1811 Expr *BitWidth = (Expr*)BitfieldWidth; 1812 SourceLocation Loc = DeclStart; 1813 if (II) Loc = D.getIdentifierLoc(); 1814 1815 // FIXME: Unnamed fields can be handled in various different ways, for 1816 // example, unnamed unions inject all members into the struct namespace! 1817 1818 1819 if (BitWidth) { 1820 // TODO: Validate. 1821 //printf("WARNING: BITFIELDS IGNORED!\n"); 1822 1823 // 6.7.2.1p3 1824 // 6.7.2.1p4 1825 1826 } else { 1827 // Not a bitfield. 1828 1829 // validate II. 1830 1831 } 1832 1833 QualType T = GetTypeForDeclarator(D, S); 1834 assert(!T.isNull() && "GetTypeForDeclarator() returned null type"); 1835 bool InvalidDecl = false; 1836 1837 // C99 6.7.2.1p8: A member of a structure or union may have any type other 1838 // than a variably modified type. 1839 if (T->isVariablyModifiedType()) { 1840 QualType FixedTy = TryFixInvalidVariablyModifiedType(T); 1841 if (!FixedTy.isNull()) { 1842 Diag(Loc, diag::warn_illegal_constant_array_size, Loc); 1843 T = FixedTy; 1844 } else { 1845 // FIXME: This diagnostic needs work 1846 Diag(Loc, diag::err_typecheck_illegal_vla, Loc); 1847 InvalidDecl = true; 1848 } 1849 } 1850 // FIXME: Chain fielddecls together. 1851 FieldDecl *NewFD = FieldDecl::Create(Context, Loc, II, T, BitWidth); 1852 1853 HandleDeclAttributes(NewFD, D.getDeclSpec().getAttributes(), 1854 D.getAttributes()); 1855 1856 if (D.getInvalidType() || InvalidDecl) 1857 NewFD->setInvalidDecl(); 1858 return NewFD; 1859} 1860 1861/// TranslateIvarVisibility - Translate visibility from a token ID to an 1862/// AST enum value. 1863static ObjCIvarDecl::AccessControl 1864TranslateIvarVisibility(tok::ObjCKeywordKind ivarVisibility) { 1865 switch (ivarVisibility) { 1866 case tok::objc_private: return ObjCIvarDecl::Private; 1867 case tok::objc_public: return ObjCIvarDecl::Public; 1868 case tok::objc_protected: return ObjCIvarDecl::Protected; 1869 case tok::objc_package: return ObjCIvarDecl::Package; 1870 default: assert(false && "Unknown visitibility kind"); 1871 } 1872} 1873 1874/// ActOnIvar - Each ivar field of an objective-c class is passed into this 1875/// in order to create an IvarDecl object for it. 1876Sema::DeclTy *Sema::ActOnIvar(Scope *S, 1877 SourceLocation DeclStart, 1878 Declarator &D, ExprTy *BitfieldWidth, 1879 tok::ObjCKeywordKind Visibility) { 1880 IdentifierInfo *II = D.getIdentifier(); 1881 Expr *BitWidth = (Expr*)BitfieldWidth; 1882 SourceLocation Loc = DeclStart; 1883 if (II) Loc = D.getIdentifierLoc(); 1884 1885 // FIXME: Unnamed fields can be handled in various different ways, for 1886 // example, unnamed unions inject all members into the struct namespace! 1887 1888 1889 if (BitWidth) { 1890 // TODO: Validate. 1891 //printf("WARNING: BITFIELDS IGNORED!\n"); 1892 1893 // 6.7.2.1p3 1894 // 6.7.2.1p4 1895 1896 } else { 1897 // Not a bitfield. 1898 1899 // validate II. 1900 1901 } 1902 1903 QualType T = GetTypeForDeclarator(D, S); 1904 assert(!T.isNull() && "GetTypeForDeclarator() returned null type"); 1905 bool InvalidDecl = false; 1906 1907 // C99 6.7.2.1p8: A member of a structure or union may have any type other 1908 // than a variably modified type. 1909 if (T->isVariablyModifiedType()) { 1910 // FIXME: This diagnostic needs work 1911 Diag(Loc, diag::err_typecheck_illegal_vla, Loc); 1912 InvalidDecl = true; 1913 } 1914 1915 ObjCIvarDecl *NewID = ObjCIvarDecl::Create(Context, Loc, II, T); 1916 1917 HandleDeclAttributes(NewID, D.getDeclSpec().getAttributes(), 1918 D.getAttributes()); 1919 1920 if (D.getInvalidType() || InvalidDecl) 1921 NewID->setInvalidDecl(); 1922 // If we have visibility info, make sure the AST is set accordingly. 1923 if (Visibility != tok::objc_not_keyword) 1924 NewID->setAccessControl(TranslateIvarVisibility(Visibility)); 1925 return NewID; 1926} 1927 1928void Sema::ActOnFields(Scope* S, 1929 SourceLocation RecLoc, DeclTy *RecDecl, 1930 DeclTy **Fields, unsigned NumFields, 1931 SourceLocation LBrac, SourceLocation RBrac) { 1932 Decl *EnclosingDecl = static_cast<Decl*>(RecDecl); 1933 assert(EnclosingDecl && "missing record or interface decl"); 1934 RecordDecl *Record = dyn_cast<RecordDecl>(EnclosingDecl); 1935 1936 if (Record && Record->isDefinition()) { 1937 // Diagnose code like: 1938 // struct S { struct S {} X; }; 1939 // We discover this when we complete the outer S. Reject and ignore the 1940 // outer S. 1941 Diag(Record->getLocation(), diag::err_nested_redefinition, 1942 Record->getKindName()); 1943 Diag(RecLoc, diag::err_previous_definition); 1944 Record->setInvalidDecl(); 1945 return; 1946 } 1947 // Verify that all the fields are okay. 1948 unsigned NumNamedMembers = 0; 1949 llvm::SmallVector<FieldDecl*, 32> RecFields; 1950 llvm::SmallSet<const IdentifierInfo*, 32> FieldIDs; 1951 1952 for (unsigned i = 0; i != NumFields; ++i) { 1953 1954 FieldDecl *FD = cast_or_null<FieldDecl>(static_cast<Decl*>(Fields[i])); 1955 assert(FD && "missing field decl"); 1956 1957 // Remember all fields. 1958 RecFields.push_back(FD); 1959 1960 // Get the type for the field. 1961 Type *FDTy = FD->getType().getTypePtr(); 1962 1963 // C99 6.7.2.1p2 - A field may not be a function type. 1964 if (FDTy->isFunctionType()) { 1965 Diag(FD->getLocation(), diag::err_field_declared_as_function, 1966 FD->getName()); 1967 FD->setInvalidDecl(); 1968 EnclosingDecl->setInvalidDecl(); 1969 continue; 1970 } 1971 // C99 6.7.2.1p2 - A field may not be an incomplete type except... 1972 if (FDTy->isIncompleteType()) { 1973 if (!Record) { // Incomplete ivar type is always an error. 1974 Diag(FD->getLocation(), diag::err_field_incomplete, FD->getName()); 1975 FD->setInvalidDecl(); 1976 EnclosingDecl->setInvalidDecl(); 1977 continue; 1978 } 1979 if (i != NumFields-1 || // ... that the last member ... 1980 !Record->isStruct() || // ... of a structure ... 1981 !FDTy->isArrayType()) { //... may have incomplete array type. 1982 Diag(FD->getLocation(), diag::err_field_incomplete, FD->getName()); 1983 FD->setInvalidDecl(); 1984 EnclosingDecl->setInvalidDecl(); 1985 continue; 1986 } 1987 if (NumNamedMembers < 1) { //... must have more than named member ... 1988 Diag(FD->getLocation(), diag::err_flexible_array_empty_struct, 1989 FD->getName()); 1990 FD->setInvalidDecl(); 1991 EnclosingDecl->setInvalidDecl(); 1992 continue; 1993 } 1994 // Okay, we have a legal flexible array member at the end of the struct. 1995 if (Record) 1996 Record->setHasFlexibleArrayMember(true); 1997 } 1998 /// C99 6.7.2.1p2 - a struct ending in a flexible array member cannot be the 1999 /// field of another structure or the element of an array. 2000 if (const RecordType *FDTTy = FDTy->getAsRecordType()) { 2001 if (FDTTy->getDecl()->hasFlexibleArrayMember()) { 2002 // If this is a member of a union, then entire union becomes "flexible". 2003 if (Record && Record->isUnion()) { 2004 Record->setHasFlexibleArrayMember(true); 2005 } else { 2006 // If this is a struct/class and this is not the last element, reject 2007 // it. Note that GCC supports variable sized arrays in the middle of 2008 // structures. 2009 if (i != NumFields-1) { 2010 Diag(FD->getLocation(), diag::err_variable_sized_type_in_struct, 2011 FD->getName()); 2012 FD->setInvalidDecl(); 2013 EnclosingDecl->setInvalidDecl(); 2014 continue; 2015 } 2016 // We support flexible arrays at the end of structs in other structs 2017 // as an extension. 2018 Diag(FD->getLocation(), diag::ext_flexible_array_in_struct, 2019 FD->getName()); 2020 if (Record) 2021 Record->setHasFlexibleArrayMember(true); 2022 } 2023 } 2024 } 2025 /// A field cannot be an Objective-c object 2026 if (FDTy->isObjCInterfaceType()) { 2027 Diag(FD->getLocation(), diag::err_statically_allocated_object, 2028 FD->getName()); 2029 FD->setInvalidDecl(); 2030 EnclosingDecl->setInvalidDecl(); 2031 continue; 2032 } 2033 // Keep track of the number of named members. 2034 if (IdentifierInfo *II = FD->getIdentifier()) { 2035 // Detect duplicate member names. 2036 if (!FieldIDs.insert(II)) { 2037 Diag(FD->getLocation(), diag::err_duplicate_member, II->getName()); 2038 // Find the previous decl. 2039 SourceLocation PrevLoc; 2040 for (unsigned i = 0, e = RecFields.size(); ; ++i) { 2041 assert(i != e && "Didn't find previous def!"); 2042 if (RecFields[i]->getIdentifier() == II) { 2043 PrevLoc = RecFields[i]->getLocation(); 2044 break; 2045 } 2046 } 2047 Diag(PrevLoc, diag::err_previous_definition); 2048 FD->setInvalidDecl(); 2049 EnclosingDecl->setInvalidDecl(); 2050 continue; 2051 } 2052 ++NumNamedMembers; 2053 } 2054 } 2055 2056 // Okay, we successfully defined 'Record'. 2057 if (Record) { 2058 Record->defineBody(&RecFields[0], RecFields.size()); 2059 Consumer.HandleTagDeclDefinition(Record); 2060 } else { 2061 ObjCIvarDecl **ClsFields = reinterpret_cast<ObjCIvarDecl**>(&RecFields[0]); 2062 if (ObjCInterfaceDecl *ID = dyn_cast<ObjCInterfaceDecl>(EnclosingDecl)) 2063 ID->addInstanceVariablesToClass(ClsFields, RecFields.size(), RBrac); 2064 else if (ObjCImplementationDecl *IMPDecl = 2065 dyn_cast<ObjCImplementationDecl>(EnclosingDecl)) { 2066 assert(IMPDecl && "ActOnFields - missing ObjCImplementationDecl"); 2067 IMPDecl->ObjCAddInstanceVariablesToClassImpl(ClsFields, RecFields.size()); 2068 CheckImplementationIvars(IMPDecl, ClsFields, RecFields.size(), RBrac); 2069 } 2070 } 2071} 2072 2073Sema::DeclTy *Sema::ActOnEnumConstant(Scope *S, DeclTy *theEnumDecl, 2074 DeclTy *lastEnumConst, 2075 SourceLocation IdLoc, IdentifierInfo *Id, 2076 SourceLocation EqualLoc, ExprTy *val) { 2077 EnumDecl *TheEnumDecl = cast<EnumDecl>(static_cast<Decl*>(theEnumDecl)); 2078 EnumConstantDecl *LastEnumConst = 2079 cast_or_null<EnumConstantDecl>(static_cast<Decl*>(lastEnumConst)); 2080 Expr *Val = static_cast<Expr*>(val); 2081 2082 // The scope passed in may not be a decl scope. Zip up the scope tree until 2083 // we find one that is. 2084 while ((S->getFlags() & Scope::DeclScope) == 0) 2085 S = S->getParent(); 2086 2087 // Verify that there isn't already something declared with this name in this 2088 // scope. 2089 if (Decl *PrevDecl = LookupDecl(Id, Decl::IDNS_Ordinary, S)) { 2090 if (IdResolver.isDeclInScope(PrevDecl, CurContext, S)) { 2091 if (isa<EnumConstantDecl>(PrevDecl)) 2092 Diag(IdLoc, diag::err_redefinition_of_enumerator, Id->getName()); 2093 else 2094 Diag(IdLoc, diag::err_redefinition, Id->getName()); 2095 Diag(PrevDecl->getLocation(), diag::err_previous_definition); 2096 delete Val; 2097 return 0; 2098 } 2099 } 2100 2101 llvm::APSInt EnumVal(32); 2102 QualType EltTy; 2103 if (Val) { 2104 // Make sure to promote the operand type to int. 2105 UsualUnaryConversions(Val); 2106 2107 // C99 6.7.2.2p2: Make sure we have an integer constant expression. 2108 SourceLocation ExpLoc; 2109 if (!Val->isIntegerConstantExpr(EnumVal, Context, &ExpLoc)) { 2110 Diag(ExpLoc, diag::err_enum_value_not_integer_constant_expr, 2111 Id->getName()); 2112 delete Val; 2113 Val = 0; // Just forget about it. 2114 } else { 2115 EltTy = Val->getType(); 2116 } 2117 } 2118 2119 if (!Val) { 2120 if (LastEnumConst) { 2121 // Assign the last value + 1. 2122 EnumVal = LastEnumConst->getInitVal(); 2123 ++EnumVal; 2124 2125 // Check for overflow on increment. 2126 if (EnumVal < LastEnumConst->getInitVal()) 2127 Diag(IdLoc, diag::warn_enum_value_overflow); 2128 2129 EltTy = LastEnumConst->getType(); 2130 } else { 2131 // First value, set to zero. 2132 EltTy = Context.IntTy; 2133 EnumVal.zextOrTrunc(static_cast<uint32_t>(Context.getTypeSize(EltTy))); 2134 } 2135 } 2136 2137 EnumConstantDecl *New = 2138 EnumConstantDecl::Create(Context, TheEnumDecl, IdLoc, Id, EltTy, 2139 Val, EnumVal, 2140 LastEnumConst); 2141 2142 // Register this decl in the current scope stack. 2143 PushOnScopeChains(New, S); 2144 return New; 2145} 2146 2147void Sema::ActOnEnumBody(SourceLocation EnumLoc, DeclTy *EnumDeclX, 2148 DeclTy **Elements, unsigned NumElements) { 2149 EnumDecl *Enum = cast<EnumDecl>(static_cast<Decl*>(EnumDeclX)); 2150 assert(!Enum->isDefinition() && "Enum redefinitions can't reach here"); 2151 2152 // TODO: If the result value doesn't fit in an int, it must be a long or long 2153 // long value. ISO C does not support this, but GCC does as an extension, 2154 // emit a warning. 2155 unsigned IntWidth = Context.Target.getIntWidth(); 2156 2157 // Verify that all the values are okay, compute the size of the values, and 2158 // reverse the list. 2159 unsigned NumNegativeBits = 0; 2160 unsigned NumPositiveBits = 0; 2161 2162 // Keep track of whether all elements have type int. 2163 bool AllElementsInt = true; 2164 2165 EnumConstantDecl *EltList = 0; 2166 for (unsigned i = 0; i != NumElements; ++i) { 2167 EnumConstantDecl *ECD = 2168 cast_or_null<EnumConstantDecl>(static_cast<Decl*>(Elements[i])); 2169 if (!ECD) continue; // Already issued a diagnostic. 2170 2171 // If the enum value doesn't fit in an int, emit an extension warning. 2172 const llvm::APSInt &InitVal = ECD->getInitVal(); 2173 assert(InitVal.getBitWidth() >= IntWidth && 2174 "Should have promoted value to int"); 2175 if (InitVal.getBitWidth() > IntWidth) { 2176 llvm::APSInt V(InitVal); 2177 V.trunc(IntWidth); 2178 V.extend(InitVal.getBitWidth()); 2179 if (V != InitVal) 2180 Diag(ECD->getLocation(), diag::ext_enum_value_not_int, 2181 InitVal.toString()); 2182 } 2183 2184 // Keep track of the size of positive and negative values. 2185 if (InitVal.isUnsigned() || InitVal.isNonNegative()) 2186 NumPositiveBits = std::max(NumPositiveBits, 2187 (unsigned)InitVal.getActiveBits()); 2188 else 2189 NumNegativeBits = std::max(NumNegativeBits, 2190 (unsigned)InitVal.getMinSignedBits()); 2191 2192 // Keep track of whether every enum element has type int (very commmon). 2193 if (AllElementsInt) 2194 AllElementsInt = ECD->getType() == Context.IntTy; 2195 2196 ECD->setNextDeclarator(EltList); 2197 EltList = ECD; 2198 } 2199 2200 // Figure out the type that should be used for this enum. 2201 // FIXME: Support attribute(packed) on enums and -fshort-enums. 2202 QualType BestType; 2203 unsigned BestWidth; 2204 2205 if (NumNegativeBits) { 2206 // If there is a negative value, figure out the smallest integer type (of 2207 // int/long/longlong) that fits. 2208 if (NumNegativeBits <= IntWidth && NumPositiveBits < IntWidth) { 2209 BestType = Context.IntTy; 2210 BestWidth = IntWidth; 2211 } else { 2212 BestWidth = Context.Target.getLongWidth(); 2213 2214 if (NumNegativeBits <= BestWidth && NumPositiveBits < BestWidth) 2215 BestType = Context.LongTy; 2216 else { 2217 BestWidth = Context.Target.getLongLongWidth(); 2218 2219 if (NumNegativeBits > BestWidth || NumPositiveBits >= BestWidth) 2220 Diag(Enum->getLocation(), diag::warn_enum_too_large); 2221 BestType = Context.LongLongTy; 2222 } 2223 } 2224 } else { 2225 // If there is no negative value, figure out which of uint, ulong, ulonglong 2226 // fits. 2227 if (NumPositiveBits <= IntWidth) { 2228 BestType = Context.UnsignedIntTy; 2229 BestWidth = IntWidth; 2230 } else if (NumPositiveBits <= 2231 (BestWidth = Context.Target.getLongWidth())) { 2232 BestType = Context.UnsignedLongTy; 2233 } else { 2234 BestWidth = Context.Target.getLongLongWidth(); 2235 assert(NumPositiveBits <= BestWidth && 2236 "How could an initializer get larger than ULL?"); 2237 BestType = Context.UnsignedLongLongTy; 2238 } 2239 } 2240 2241 // Loop over all of the enumerator constants, changing their types to match 2242 // the type of the enum if needed. 2243 for (unsigned i = 0; i != NumElements; ++i) { 2244 EnumConstantDecl *ECD = 2245 cast_or_null<EnumConstantDecl>(static_cast<Decl*>(Elements[i])); 2246 if (!ECD) continue; // Already issued a diagnostic. 2247 2248 // Standard C says the enumerators have int type, but we allow, as an 2249 // extension, the enumerators to be larger than int size. If each 2250 // enumerator value fits in an int, type it as an int, otherwise type it the 2251 // same as the enumerator decl itself. This means that in "enum { X = 1U }" 2252 // that X has type 'int', not 'unsigned'. 2253 if (ECD->getType() == Context.IntTy) { 2254 // Make sure the init value is signed. 2255 llvm::APSInt IV = ECD->getInitVal(); 2256 IV.setIsSigned(true); 2257 ECD->setInitVal(IV); 2258 continue; // Already int type. 2259 } 2260 2261 // Determine whether the value fits into an int. 2262 llvm::APSInt InitVal = ECD->getInitVal(); 2263 bool FitsInInt; 2264 if (InitVal.isUnsigned() || !InitVal.isNegative()) 2265 FitsInInt = InitVal.getActiveBits() < IntWidth; 2266 else 2267 FitsInInt = InitVal.getMinSignedBits() <= IntWidth; 2268 2269 // If it fits into an integer type, force it. Otherwise force it to match 2270 // the enum decl type. 2271 QualType NewTy; 2272 unsigned NewWidth; 2273 bool NewSign; 2274 if (FitsInInt) { 2275 NewTy = Context.IntTy; 2276 NewWidth = IntWidth; 2277 NewSign = true; 2278 } else if (ECD->getType() == BestType) { 2279 // Already the right type! 2280 continue; 2281 } else { 2282 NewTy = BestType; 2283 NewWidth = BestWidth; 2284 NewSign = BestType->isSignedIntegerType(); 2285 } 2286 2287 // Adjust the APSInt value. 2288 InitVal.extOrTrunc(NewWidth); 2289 InitVal.setIsSigned(NewSign); 2290 ECD->setInitVal(InitVal); 2291 2292 // Adjust the Expr initializer and type. 2293 ECD->setInitExpr(new ImplicitCastExpr(NewTy, ECD->getInitExpr())); 2294 ECD->setType(NewTy); 2295 } 2296 2297 Enum->defineElements(EltList, BestType); 2298 Consumer.HandleTagDeclDefinition(Enum); 2299} 2300 2301Sema::DeclTy *Sema::ActOnFileScopeAsmDecl(SourceLocation Loc, 2302 ExprTy *expr) { 2303 StringLiteral *AsmString = cast<StringLiteral>((Expr*)expr); 2304 2305 return FileScopeAsmDecl::Create(Context, Loc, AsmString); 2306} 2307 2308Sema::DeclTy* Sema::ActOnLinkageSpec(SourceLocation Loc, 2309 SourceLocation LBrace, 2310 SourceLocation RBrace, 2311 const char *Lang, 2312 unsigned StrSize, 2313 DeclTy *D) { 2314 LinkageSpecDecl::LanguageIDs Language; 2315 Decl *dcl = static_cast<Decl *>(D); 2316 if (strncmp(Lang, "\"C\"", StrSize) == 0) 2317 Language = LinkageSpecDecl::lang_c; 2318 else if (strncmp(Lang, "\"C++\"", StrSize) == 0) 2319 Language = LinkageSpecDecl::lang_cxx; 2320 else { 2321 Diag(Loc, diag::err_bad_language); 2322 return 0; 2323 } 2324 2325 // FIXME: Add all the various semantics of linkage specifications 2326 return LinkageSpecDecl::Create(Context, Loc, Language, dcl); 2327} 2328 2329void Sema::HandleDeclAttribute(Decl *New, const AttributeList *Attr) { 2330 2331 switch (Attr->getKind()) { 2332 case AttributeList::AT_vector_size: 2333 if (ValueDecl *vDecl = dyn_cast<ValueDecl>(New)) { 2334 QualType newType = HandleVectorTypeAttribute(vDecl->getType(), Attr); 2335 if (!newType.isNull()) // install the new vector type into the decl 2336 vDecl->setType(newType); 2337 } 2338 if (TypedefDecl *tDecl = dyn_cast<TypedefDecl>(New)) { 2339 QualType newType = HandleVectorTypeAttribute(tDecl->getUnderlyingType(), 2340 Attr); 2341 if (!newType.isNull()) // install the new vector type into the decl 2342 tDecl->setUnderlyingType(newType); 2343 } 2344 break; 2345 case AttributeList::AT_ext_vector_type: 2346 if (TypedefDecl *tDecl = dyn_cast<TypedefDecl>(New)) 2347 HandleExtVectorTypeAttribute(tDecl, Attr); 2348 else 2349 Diag(Attr->getLoc(), 2350 diag::err_typecheck_ext_vector_not_typedef); 2351 break; 2352 case AttributeList::AT_address_space: 2353 // Ignore this, this is a type attribute, handled by ProcessTypeAttributes. 2354 break; 2355 case AttributeList::AT_mode: 2356 // Despite what would be logical, the mode attribute is a decl attribute, 2357 // not a type attribute: 'int ** __attribute((mode(HI))) *G;' tries to make 2358 // 'G' be HImode, not an intermediate pointer. 2359 if (TypedefDecl *tDecl = dyn_cast<TypedefDecl>(New)) { 2360 QualType newType = HandleModeTypeAttribute(tDecl->getUnderlyingType(), 2361 Attr); 2362 tDecl->setUnderlyingType(newType); 2363 } else if (ValueDecl *vDecl = dyn_cast<ValueDecl>(New)) { 2364 QualType newType = HandleModeTypeAttribute(vDecl->getType(), Attr); 2365 vDecl->setType(newType); 2366 } 2367 // FIXME: Diagnostic? 2368 break; 2369 case AttributeList::AT_alias: 2370 HandleAliasAttribute(New, Attr); 2371 break; 2372 case AttributeList::AT_deprecated: 2373 HandleDeprecatedAttribute(New, Attr); 2374 break; 2375 case AttributeList::AT_visibility: 2376 HandleVisibilityAttribute(New, Attr); 2377 break; 2378 case AttributeList::AT_weak: 2379 HandleWeakAttribute(New, Attr); 2380 break; 2381 case AttributeList::AT_dllimport: 2382 HandleDLLImportAttribute(New, Attr); 2383 break; 2384 case AttributeList::AT_dllexport: 2385 HandleDLLExportAttribute(New, Attr); 2386 break; 2387 case AttributeList::AT_nothrow: 2388 HandleNothrowAttribute(New, Attr); 2389 break; 2390 case AttributeList::AT_stdcall: 2391 HandleStdCallAttribute(New, Attr); 2392 break; 2393 case AttributeList::AT_fastcall: 2394 HandleFastCallAttribute(New, Attr); 2395 break; 2396 case AttributeList::AT_aligned: 2397 HandleAlignedAttribute(New, Attr); 2398 break; 2399 case AttributeList::AT_packed: 2400 HandlePackedAttribute(New, Attr); 2401 break; 2402 case AttributeList::AT_annotate: 2403 HandleAnnotateAttribute(New, Attr); 2404 break; 2405 case AttributeList::AT_noreturn: 2406 HandleNoReturnAttribute(New, Attr); 2407 break; 2408 case AttributeList::AT_format: 2409 HandleFormatAttribute(New, Attr); 2410 break; 2411 case AttributeList::AT_transparent_union: 2412 HandleTransparentUnionAttribute(New, Attr); 2413 break; 2414 default: 2415#if 0 2416 // TODO: when we have the full set of attributes, warn about unknown ones. 2417 Diag(Attr->getLoc(), diag::warn_attribute_ignored, 2418 Attr->getName()->getName()); 2419#endif 2420 break; 2421 } 2422} 2423 2424void Sema::HandleDeclAttributes(Decl *New, const AttributeList *DeclSpecAttrs, 2425 const AttributeList *DeclaratorAttrs) { 2426 if (DeclSpecAttrs == 0 && DeclaratorAttrs == 0) return; 2427 2428 while (DeclSpecAttrs) { 2429 HandleDeclAttribute(New, DeclSpecAttrs); 2430 DeclSpecAttrs = DeclSpecAttrs->getNext(); 2431 } 2432 2433 // If there are any type attributes that were in the declarator, apply them to 2434 // its top level type. 2435 if (ValueDecl *VD = dyn_cast<ValueDecl>(New)) { 2436 QualType DT = VD->getType(); 2437 ProcessTypeAttributes(DT, DeclaratorAttrs); 2438 VD->setType(DT); 2439 } else if (TypedefDecl *TD = dyn_cast<TypedefDecl>(New)) { 2440 QualType DT = TD->getUnderlyingType(); 2441 ProcessTypeAttributes(DT, DeclaratorAttrs); 2442 TD->setUnderlyingType(DT); 2443 } 2444 2445 while (DeclaratorAttrs) { 2446 HandleDeclAttribute(New, DeclaratorAttrs); 2447 DeclaratorAttrs = DeclaratorAttrs->getNext(); 2448 } 2449} 2450 2451void Sema::HandleExtVectorTypeAttribute(TypedefDecl *tDecl, 2452 const AttributeList *rawAttr) { 2453 QualType curType = tDecl->getUnderlyingType(); 2454 // check the attribute arguments. 2455 if (rawAttr->getNumArgs() != 1) { 2456 Diag(rawAttr->getLoc(), diag::err_attribute_wrong_number_arguments, 2457 std::string("1")); 2458 return; 2459 } 2460 Expr *sizeExpr = static_cast<Expr *>(rawAttr->getArg(0)); 2461 llvm::APSInt vecSize(32); 2462 if (!sizeExpr->isIntegerConstantExpr(vecSize, Context)) { 2463 Diag(rawAttr->getLoc(), diag::err_attribute_argument_not_int, 2464 "ext_vector_type", sizeExpr->getSourceRange()); 2465 return; 2466 } 2467 // unlike gcc's vector_size attribute, we do not allow vectors to be defined 2468 // in conjunction with complex types (pointers, arrays, functions, etc.). 2469 Type *canonType = curType.getCanonicalType().getTypePtr(); 2470 if (!(canonType->isIntegerType() || canonType->isRealFloatingType())) { 2471 Diag(rawAttr->getLoc(), diag::err_attribute_invalid_vector_type, 2472 curType.getCanonicalType().getAsString()); 2473 return; 2474 } 2475 // unlike gcc's vector_size attribute, the size is specified as the 2476 // number of elements, not the number of bytes. 2477 unsigned vectorSize = static_cast<unsigned>(vecSize.getZExtValue()); 2478 2479 if (vectorSize == 0) { 2480 Diag(rawAttr->getLoc(), diag::err_attribute_zero_size, 2481 sizeExpr->getSourceRange()); 2482 return; 2483 } 2484 // Instantiate/Install the vector type, the number of elements is > 0. 2485 tDecl->setUnderlyingType(Context.getExtVectorType(curType, vectorSize)); 2486 // Remember this typedef decl, we will need it later for diagnostics. 2487 ExtVectorDecls.push_back(tDecl); 2488} 2489 2490QualType Sema::HandleVectorTypeAttribute(QualType curType, 2491 const AttributeList *rawAttr) { 2492 // check the attribute arugments. 2493 if (rawAttr->getNumArgs() != 1) { 2494 Diag(rawAttr->getLoc(), diag::err_attribute_wrong_number_arguments, 2495 std::string("1")); 2496 return QualType(); 2497 } 2498 Expr *sizeExpr = static_cast<Expr *>(rawAttr->getArg(0)); 2499 llvm::APSInt vecSize(32); 2500 if (!sizeExpr->isIntegerConstantExpr(vecSize, Context)) { 2501 Diag(rawAttr->getLoc(), diag::err_attribute_argument_not_int, 2502 "vector_size", sizeExpr->getSourceRange()); 2503 return QualType(); 2504 } 2505 // navigate to the base type - we need to provide for vector pointers, 2506 // vector arrays, and functions returning vectors. 2507 Type *canonType = curType.getCanonicalType().getTypePtr(); 2508 2509 if (canonType->isPointerType() || canonType->isArrayType() || 2510 canonType->isFunctionType()) { 2511 assert(0 && "HandleVector(): Complex type construction unimplemented"); 2512 /* FIXME: rebuild the type from the inside out, vectorizing the inner type. 2513 do { 2514 if (PointerType *PT = dyn_cast<PointerType>(canonType)) 2515 canonType = PT->getPointeeType().getTypePtr(); 2516 else if (ArrayType *AT = dyn_cast<ArrayType>(canonType)) 2517 canonType = AT->getElementType().getTypePtr(); 2518 else if (FunctionType *FT = dyn_cast<FunctionType>(canonType)) 2519 canonType = FT->getResultType().getTypePtr(); 2520 } while (canonType->isPointerType() || canonType->isArrayType() || 2521 canonType->isFunctionType()); 2522 */ 2523 } 2524 // the base type must be integer or float. 2525 if (!(canonType->isIntegerType() || canonType->isRealFloatingType())) { 2526 Diag(rawAttr->getLoc(), diag::err_attribute_invalid_vector_type, 2527 curType.getCanonicalType().getAsString()); 2528 return QualType(); 2529 } 2530 unsigned typeSize = static_cast<unsigned>(Context.getTypeSize(curType)); 2531 // vecSize is specified in bytes - convert to bits. 2532 unsigned vectorSize = static_cast<unsigned>(vecSize.getZExtValue() * 8); 2533 2534 // the vector size needs to be an integral multiple of the type size. 2535 if (vectorSize % typeSize) { 2536 Diag(rawAttr->getLoc(), diag::err_attribute_invalid_size, 2537 sizeExpr->getSourceRange()); 2538 return QualType(); 2539 } 2540 if (vectorSize == 0) { 2541 Diag(rawAttr->getLoc(), diag::err_attribute_zero_size, 2542 sizeExpr->getSourceRange()); 2543 return QualType(); 2544 } 2545 // Instantiate the vector type, the number of elements is > 0, and not 2546 // required to be a power of 2, unlike GCC. 2547 return Context.getVectorType(curType, vectorSize/typeSize); 2548} 2549 2550void Sema::HandlePackedAttribute(Decl *d, const AttributeList *rawAttr) { 2551 // check the attribute arguments. 2552 if (rawAttr->getNumArgs() > 0) { 2553 Diag(rawAttr->getLoc(), diag::err_attribute_wrong_number_arguments, 2554 std::string("0")); 2555 return; 2556 } 2557 2558 if (TagDecl *TD = dyn_cast<TagDecl>(d)) 2559 TD->addAttr(new PackedAttr); 2560 else if (FieldDecl *FD = dyn_cast<FieldDecl>(d)) { 2561 // If the alignment is less than or equal to 8 bits, the packed attribute 2562 // has no effect. 2563 if (!FD->getType()->isIncompleteType() && 2564 Context.getTypeAlign(FD->getType()) <= 8) 2565 Diag(rawAttr->getLoc(), 2566 diag::warn_attribute_ignored_for_field_of_type, 2567 rawAttr->getName()->getName(), FD->getType().getAsString()); 2568 else 2569 FD->addAttr(new PackedAttr); 2570 } else 2571 Diag(rawAttr->getLoc(), diag::warn_attribute_ignored, 2572 rawAttr->getName()->getName()); 2573} 2574 2575void Sema::HandleAliasAttribute(Decl *d, const AttributeList *rawAttr) { 2576 // check the attribute arguments. 2577 if (rawAttr->getNumArgs() != 1) { 2578 Diag(rawAttr->getLoc(), diag::err_attribute_wrong_number_arguments, 2579 std::string("1")); 2580 return; 2581 } 2582 2583 Expr *Arg = static_cast<Expr*>(rawAttr->getArg(0)); 2584 Arg = Arg->IgnoreParenCasts(); 2585 StringLiteral *Str = dyn_cast<StringLiteral>(Arg); 2586 2587 if (Str == 0 || Str->isWide()) { 2588 Diag(rawAttr->getLoc(), diag::err_attribute_argument_n_not_string, 2589 "alias", std::string("1")); 2590 return; 2591 } 2592 2593 const char *Alias = Str->getStrData(); 2594 unsigned AliasLen = Str->getByteLength(); 2595 2596 // FIXME: check if target symbol exists in current file 2597 2598 d->addAttr(new AliasAttr(std::string(Alias, AliasLen))); 2599} 2600 2601void Sema::HandleNoReturnAttribute(Decl *d, const AttributeList *rawAttr) { 2602 // check the attribute arguments. 2603 if (rawAttr->getNumArgs() != 0) { 2604 Diag(rawAttr->getLoc(), diag::err_attribute_wrong_number_arguments, 2605 std::string("0")); 2606 return; 2607 } 2608 2609 FunctionDecl *Fn = dyn_cast<FunctionDecl>(d); 2610 2611 if (!Fn) { 2612 Diag(rawAttr->getLoc(), diag::warn_attribute_wrong_decl_type, 2613 "noreturn", "function"); 2614 return; 2615 } 2616 2617 d->addAttr(new NoReturnAttr()); 2618} 2619 2620void Sema::HandleDeprecatedAttribute(Decl *d, const AttributeList *rawAttr) { 2621 // check the attribute arguments. 2622 if (rawAttr->getNumArgs() != 0) { 2623 Diag(rawAttr->getLoc(), diag::err_attribute_wrong_number_arguments, 2624 std::string("0")); 2625 return; 2626 } 2627 2628 d->addAttr(new DeprecatedAttr()); 2629} 2630 2631void Sema::HandleVisibilityAttribute(Decl *d, const AttributeList *rawAttr) { 2632 // check the attribute arguments. 2633 if (rawAttr->getNumArgs() != 1) { 2634 Diag(rawAttr->getLoc(), diag::err_attribute_wrong_number_arguments, 2635 std::string("1")); 2636 return; 2637 } 2638 2639 Expr *Arg = static_cast<Expr*>(rawAttr->getArg(0)); 2640 Arg = Arg->IgnoreParenCasts(); 2641 StringLiteral *Str = dyn_cast<StringLiteral>(Arg); 2642 2643 if (Str == 0 || Str->isWide()) { 2644 Diag(rawAttr->getLoc(), diag::err_attribute_argument_n_not_string, 2645 "visibility", std::string("1")); 2646 return; 2647 } 2648 2649 const char *TypeStr = Str->getStrData(); 2650 unsigned TypeLen = Str->getByteLength(); 2651 VisibilityAttr::VisibilityTypes type; 2652 2653 if (TypeLen == 7 && !memcmp(TypeStr, "default", 7)) 2654 type = VisibilityAttr::DefaultVisibility; 2655 else if (TypeLen == 6 && !memcmp(TypeStr, "hidden", 6)) 2656 type = VisibilityAttr::HiddenVisibility; 2657 else if (TypeLen == 8 && !memcmp(TypeStr, "internal", 8)) 2658 type = VisibilityAttr::HiddenVisibility; // FIXME 2659 else if (TypeLen == 9 && !memcmp(TypeStr, "protected", 9)) 2660 type = VisibilityAttr::ProtectedVisibility; 2661 else { 2662 Diag(rawAttr->getLoc(), diag::warn_attribute_type_not_supported, 2663 "visibility", TypeStr); 2664 return; 2665 } 2666 2667 d->addAttr(new VisibilityAttr(type)); 2668} 2669 2670void Sema::HandleWeakAttribute(Decl *d, const AttributeList *rawAttr) { 2671 // check the attribute arguments. 2672 if (rawAttr->getNumArgs() != 0) { 2673 Diag(rawAttr->getLoc(), diag::err_attribute_wrong_number_arguments, 2674 std::string("0")); 2675 return; 2676 } 2677 2678 d->addAttr(new WeakAttr()); 2679} 2680 2681void Sema::HandleDLLImportAttribute(Decl *d, const AttributeList *rawAttr) { 2682 // check the attribute arguments. 2683 if (rawAttr->getNumArgs() != 0) { 2684 Diag(rawAttr->getLoc(), diag::err_attribute_wrong_number_arguments, 2685 std::string("0")); 2686 return; 2687 } 2688 2689 d->addAttr(new DLLImportAttr()); 2690} 2691 2692void Sema::HandleDLLExportAttribute(Decl *d, const AttributeList *rawAttr) { 2693 // check the attribute arguments. 2694 if (rawAttr->getNumArgs() != 0) { 2695 Diag(rawAttr->getLoc(), diag::err_attribute_wrong_number_arguments, 2696 std::string("0")); 2697 return; 2698 } 2699 2700 d->addAttr(new DLLExportAttr()); 2701} 2702 2703void Sema::HandleStdCallAttribute(Decl *d, const AttributeList *rawAttr) { 2704 // check the attribute arguments. 2705 if (rawAttr->getNumArgs() != 0) { 2706 Diag(rawAttr->getLoc(), diag::err_attribute_wrong_number_arguments, 2707 std::string("0")); 2708 return; 2709 } 2710 2711 d->addAttr(new StdCallAttr()); 2712} 2713 2714void Sema::HandleFastCallAttribute(Decl *d, const AttributeList *rawAttr) { 2715 // check the attribute arguments. 2716 if (rawAttr->getNumArgs() != 0) { 2717 Diag(rawAttr->getLoc(), diag::err_attribute_wrong_number_arguments, 2718 std::string("0")); 2719 return; 2720 } 2721 2722 d->addAttr(new FastCallAttr()); 2723} 2724 2725void Sema::HandleNothrowAttribute(Decl *d, const AttributeList *rawAttr) { 2726 // check the attribute arguments. 2727 if (rawAttr->getNumArgs() != 0) { 2728 Diag(rawAttr->getLoc(), diag::err_attribute_wrong_number_arguments, 2729 std::string("0")); 2730 return; 2731 } 2732 2733 d->addAttr(new NoThrowAttr()); 2734} 2735 2736static const FunctionTypeProto *getFunctionProto(Decl *d) { 2737 QualType Ty; 2738 2739 if (ValueDecl *decl = dyn_cast<ValueDecl>(d)) 2740 Ty = decl->getType(); 2741 else if (FieldDecl *decl = dyn_cast<FieldDecl>(d)) 2742 Ty = decl->getType(); 2743 else if (TypedefDecl* decl = dyn_cast<TypedefDecl>(d)) 2744 Ty = decl->getUnderlyingType(); 2745 else 2746 return 0; 2747 2748 if (Ty->isFunctionPointerType()) { 2749 const PointerType *PtrTy = Ty->getAsPointerType(); 2750 Ty = PtrTy->getPointeeType(); 2751 } 2752 2753 if (const FunctionType *FnTy = Ty->getAsFunctionType()) 2754 return dyn_cast<FunctionTypeProto>(FnTy->getAsFunctionType()); 2755 2756 return 0; 2757} 2758 2759static inline bool isNSStringType(QualType T, ASTContext &Ctx) { 2760 if (!T->isPointerType()) 2761 return false; 2762 2763 T = T->getAsPointerType()->getPointeeType().getCanonicalType(); 2764 ObjCInterfaceType* ClsT = dyn_cast<ObjCInterfaceType>(T.getTypePtr()); 2765 2766 if (!ClsT) 2767 return false; 2768 2769 IdentifierInfo* ClsName = ClsT->getDecl()->getIdentifier(); 2770 2771 // FIXME: Should we walk the chain of classes? 2772 return ClsName == &Ctx.Idents.get("NSString") || 2773 ClsName == &Ctx.Idents.get("NSMutableString"); 2774} 2775 2776/// Handle __attribute__((format(type,idx,firstarg))) attributes 2777/// based on http://gcc.gnu.org/onlinedocs/gcc/Function-Attributes.html 2778void Sema::HandleFormatAttribute(Decl *d, const AttributeList *rawAttr) { 2779 2780 if (!rawAttr->getParameterName()) { 2781 Diag(rawAttr->getLoc(), diag::err_attribute_argument_n_not_string, 2782 "format", std::string("1")); 2783 return; 2784 } 2785 2786 if (rawAttr->getNumArgs() != 2) { 2787 Diag(rawAttr->getLoc(), diag::err_attribute_wrong_number_arguments, 2788 std::string("3")); 2789 return; 2790 } 2791 2792 // GCC ignores the format attribute on K&R style function 2793 // prototypes, so we ignore it as well 2794 const FunctionTypeProto *proto = getFunctionProto(d); 2795 2796 if (!proto) { 2797 Diag(rawAttr->getLoc(), diag::warn_attribute_wrong_decl_type, 2798 "format", "function"); 2799 return; 2800 } 2801 2802 // FIXME: in C++ the implicit 'this' function parameter also counts. 2803 // this is needed in order to be compatible with GCC 2804 // the index must start in 1 and the limit is numargs+1 2805 unsigned NumArgs = proto->getNumArgs(); 2806 unsigned FirstIdx = 1; 2807 2808 const char *Format = rawAttr->getParameterName()->getName(); 2809 unsigned FormatLen = rawAttr->getParameterName()->getLength(); 2810 2811 // Normalize the argument, __foo__ becomes foo. 2812 if (FormatLen > 4 && Format[0] == '_' && Format[1] == '_' && 2813 Format[FormatLen - 2] == '_' && Format[FormatLen - 1] == '_') { 2814 Format += 2; 2815 FormatLen -= 4; 2816 } 2817 2818 bool Supported = false; 2819 bool is_NSString = false; 2820 bool is_strftime = false; 2821 2822 switch (FormatLen) { 2823 default: break; 2824 case 5: 2825 Supported = !memcmp(Format, "scanf", 5); 2826 break; 2827 case 6: 2828 Supported = !memcmp(Format, "printf", 6); 2829 break; 2830 case 7: 2831 Supported = !memcmp(Format, "strfmon", 7); 2832 break; 2833 case 8: 2834 Supported = (is_strftime = !memcmp(Format, "strftime", 8)) || 2835 (is_NSString = !memcmp(Format, "NSString", 8)); 2836 break; 2837 } 2838 2839 if (!Supported) { 2840 Diag(rawAttr->getLoc(), diag::warn_attribute_type_not_supported, 2841 "format", rawAttr->getParameterName()->getName()); 2842 return; 2843 } 2844 2845 // checks for the 2nd argument 2846 Expr *IdxExpr = static_cast<Expr *>(rawAttr->getArg(0)); 2847 llvm::APSInt Idx(Context.getTypeSize(IdxExpr->getType())); 2848 if (!IdxExpr->isIntegerConstantExpr(Idx, Context)) { 2849 Diag(rawAttr->getLoc(), diag::err_attribute_argument_n_not_int, 2850 "format", std::string("2"), IdxExpr->getSourceRange()); 2851 return; 2852 } 2853 2854 if (Idx.getZExtValue() < FirstIdx || Idx.getZExtValue() > NumArgs) { 2855 Diag(rawAttr->getLoc(), diag::err_attribute_argument_out_of_bounds, 2856 "format", std::string("2"), IdxExpr->getSourceRange()); 2857 return; 2858 } 2859 2860 // FIXME: Do we need to bounds check? 2861 unsigned ArgIdx = Idx.getZExtValue() - 1; 2862 2863 // make sure the format string is really a string 2864 QualType Ty = proto->getArgType(ArgIdx); 2865 2866 if (is_NSString) { 2867 // FIXME: do we need to check if the type is NSString*? What are 2868 // the semantics? 2869 if (!isNSStringType(Ty, Context)) { 2870 // FIXME: Should highlight the actual expression that has the 2871 // wrong type. 2872 Diag(rawAttr->getLoc(), diag::err_format_attribute_not_NSString, 2873 IdxExpr->getSourceRange()); 2874 return; 2875 } 2876 } 2877 else if (!Ty->isPointerType() || 2878 !Ty->getAsPointerType()->getPointeeType()->isCharType()) { 2879 // FIXME: Should highlight the actual expression that has the 2880 // wrong type. 2881 Diag(rawAttr->getLoc(), diag::err_format_attribute_not_string, 2882 IdxExpr->getSourceRange()); 2883 return; 2884 } 2885 2886 // check the 3rd argument 2887 Expr *FirstArgExpr = static_cast<Expr *>(rawAttr->getArg(1)); 2888 llvm::APSInt FirstArg(Context.getTypeSize(FirstArgExpr->getType())); 2889 if (!FirstArgExpr->isIntegerConstantExpr(FirstArg, Context)) { 2890 Diag(rawAttr->getLoc(), diag::err_attribute_argument_n_not_int, 2891 "format", std::string("3"), FirstArgExpr->getSourceRange()); 2892 return; 2893 } 2894 2895 // check if the function is variadic if the 3rd argument non-zero 2896 if (FirstArg != 0) { 2897 if (proto->isVariadic()) { 2898 ++NumArgs; // +1 for ... 2899 } else { 2900 Diag(d->getLocation(), diag::err_format_attribute_requires_variadic); 2901 return; 2902 } 2903 } 2904 2905 // strftime requires FirstArg to be 0 because it doesn't read from any variable 2906 // the input is just the current time + the format string 2907 if (is_strftime) { 2908 if (FirstArg != 0) { 2909 Diag(rawAttr->getLoc(), diag::err_format_strftime_third_parameter, 2910 FirstArgExpr->getSourceRange()); 2911 return; 2912 } 2913 // if 0 it disables parameter checking (to use with e.g. va_list) 2914 } else if (FirstArg != 0 && FirstArg != NumArgs) { 2915 Diag(rawAttr->getLoc(), diag::err_attribute_argument_out_of_bounds, 2916 "format", std::string("3"), FirstArgExpr->getSourceRange()); 2917 return; 2918 } 2919 2920 d->addAttr(new FormatAttr(std::string(Format, FormatLen), 2921 Idx.getZExtValue(), FirstArg.getZExtValue())); 2922} 2923 2924void Sema::HandleTransparentUnionAttribute(Decl *d, 2925 const AttributeList *rawAttr) { 2926 // check the attribute arguments. 2927 if (rawAttr->getNumArgs() != 0) { 2928 Diag(rawAttr->getLoc(), diag::err_attribute_wrong_number_arguments, 2929 std::string("0")); 2930 return; 2931 } 2932 2933 TypeDecl *decl = dyn_cast<TypeDecl>(d); 2934 2935 if (!decl || !Context.getTypeDeclType(decl)->isUnionType()) { 2936 Diag(rawAttr->getLoc(), diag::warn_attribute_wrong_decl_type, 2937 "transparent_union", "union"); 2938 return; 2939 } 2940 2941 //QualType QTy = Context.getTypeDeclType(decl); 2942 //const RecordType *Ty = QTy->getAsUnionType(); 2943 2944// FIXME 2945// Ty->addAttr(new TransparentUnionAttr()); 2946} 2947 2948void Sema::HandleAnnotateAttribute(Decl *d, const AttributeList *rawAttr) { 2949 // check the attribute arguments. 2950 if (rawAttr->getNumArgs() != 1) { 2951 Diag(rawAttr->getLoc(), diag::err_attribute_wrong_number_arguments, 2952 std::string("1")); 2953 return; 2954 } 2955 Expr *argExpr = static_cast<Expr *>(rawAttr->getArg(0)); 2956 StringLiteral *SE = dyn_cast<StringLiteral>(argExpr); 2957 2958 // Make sure that there is a string literal as the annotation's single 2959 // argument. 2960 if (!SE) { 2961 Diag(rawAttr->getLoc(), diag::err_attribute_annotate_no_string); 2962 return; 2963 } 2964 d->addAttr(new AnnotateAttr(std::string(SE->getStrData(), 2965 SE->getByteLength()))); 2966} 2967 2968void Sema::HandleAlignedAttribute(Decl *d, const AttributeList *rawAttr) 2969{ 2970 // check the attribute arguments. 2971 if (rawAttr->getNumArgs() > 1) { 2972 Diag(rawAttr->getLoc(), diag::err_attribute_wrong_number_arguments, 2973 std::string("1")); 2974 return; 2975 } 2976 2977 unsigned Align = 0; 2978 2979 if (rawAttr->getNumArgs() == 0) { 2980 // FIXME: This should be the target specific maximum alignment. 2981 // (For now we just use 128 bits which is the maximum on X86. 2982 Align = 128; 2983 return; 2984 } else { 2985 Expr *alignmentExpr = static_cast<Expr *>(rawAttr->getArg(0)); 2986 llvm::APSInt alignment(32); 2987 if (!alignmentExpr->isIntegerConstantExpr(alignment, Context)) { 2988 Diag(rawAttr->getLoc(), diag::err_attribute_argument_not_int, 2989 "aligned", alignmentExpr->getSourceRange()); 2990 return; 2991 } 2992 2993 Align = alignment.getZExtValue() * 8; 2994 } 2995 2996 d->addAttr(new AlignedAttr(Align)); 2997} 2998