SemaDecl.cpp revision 998dffb089f1a7da10d66367f1c4db3a7bd12184
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/Expr.h" 21#include "clang/AST/Type.h" 22#include "clang/Parse/DeclSpec.h" 23#include "clang/Parse/Scope.h" 24#include "clang/Basic/LangOptions.h" 25#include "clang/Basic/TargetInfo.h" 26#include "clang/Basic/SourceManager.h" 27#include "clang/AST/ExprCXX.h" 28// FIXME: layering (ideally, Sema shouldn't be dependent on Lex API's) 29#include "clang/Lex/Preprocessor.h" 30#include "clang/Lex/HeaderSearch.h" 31#include "llvm/ADT/SmallString.h" 32#include "llvm/ADT/SmallSet.h" 33#include "llvm/ADT/DenseSet.h" 34using namespace clang; 35 36Sema::DeclTy *Sema::isTypeName(const IdentifierInfo &II, Scope *S) { 37 Decl *IIDecl = LookupDecl(&II, Decl::IDNS_Ordinary, S, false); 38 39 if (IIDecl && (isa<TypedefDecl>(IIDecl) || 40 isa<ObjCInterfaceDecl>(IIDecl) || 41 isa<TagDecl>(IIDecl))) 42 return IIDecl; 43 return 0; 44} 45 46void Sema::PushDeclContext(DeclContext *DC) { 47 assert( ( (isa<ObjCMethodDecl>(DC) && isa<TranslationUnitDecl>(CurContext)) 48 || DC->getParent() == CurContext ) && 49 "The next DeclContext should be directly contained in the current one."); 50 CurContext = DC; 51} 52 53void Sema::PopDeclContext() { 54 assert(CurContext && "DeclContext imbalance!"); 55 // If CurContext is a ObjC method, getParent() will return NULL. 56 CurContext = isa<ObjCMethodDecl>(CurContext) 57 ? Context.getTranslationUnitDecl() 58 : CurContext->getParent(); 59} 60 61/// Add this decl to the scope shadowed decl chains. 62void Sema::PushOnScopeChains(NamedDecl *D, Scope *S) { 63 S->AddDecl(D); 64 65 // C++ [basic.scope]p4: 66 // -- exactly one declaration shall declare a class name or 67 // enumeration name that is not a typedef name and the other 68 // declarations shall all refer to the same object or 69 // enumerator, or all refer to functions and function templates; 70 // in this case the class name or enumeration name is hidden. 71 if (TagDecl *TD = dyn_cast<TagDecl>(D)) { 72 // We are pushing the name of a tag (enum or class). 73 IdentifierResolver::ctx_iterator 74 CIT = IdResolver.ctx_begin(TD->getIdentifier(), TD->getDeclContext()); 75 if (CIT != IdResolver.ctx_end(TD->getIdentifier()) && 76 IdResolver.isDeclInScope(*CIT, TD->getDeclContext(), S)) { 77 // There is already a declaration with the same name in the same 78 // scope. It must be found before we find the new declaration, 79 // so swap the order on the shadowed declaration chain. 80 81 IdResolver.AddShadowedDecl(TD, *CIT); 82 return; 83 } 84 } 85 86 IdResolver.AddDecl(D); 87} 88 89void Sema::ActOnPopScope(SourceLocation Loc, Scope *S) { 90 if (S->decl_empty()) return; 91 assert((S->getFlags() & Scope::DeclScope) &&"Scope shouldn't contain decls!"); 92 93 // We only want to remove the decls from the identifier decl chains for local 94 // scopes, when inside a function/method. 95 if (S->getFnParent() == 0) 96 return; 97 98 for (Scope::decl_iterator I = S->decl_begin(), E = S->decl_end(); 99 I != E; ++I) { 100 Decl *TmpD = static_cast<Decl*>(*I); 101 assert(TmpD && "This decl didn't get pushed??"); 102 ScopedDecl *D = dyn_cast<ScopedDecl>(TmpD); 103 assert(D && "This decl isn't a ScopedDecl?"); 104 105 IdentifierInfo *II = D->getIdentifier(); 106 if (!II) continue; 107 108 // Unlink this decl from the identifier. 109 IdResolver.RemoveDecl(D); 110 111 // This will have to be revisited for C++: there we want to nest stuff in 112 // namespace decls etc. Even for C, we might want a top-level translation 113 // unit decl or something. 114 if (!CurFunctionDecl) 115 continue; 116 117 // Chain this decl to the containing function, it now owns the memory for 118 // the decl. 119 D->setNext(CurFunctionDecl->getDeclChain()); 120 CurFunctionDecl->setDeclChain(D); 121 } 122} 123 124/// getObjCInterfaceDecl - Look up a for a class declaration in the scope. 125/// return 0 if one not found. 126ObjCInterfaceDecl *Sema::getObjCInterfaceDecl(IdentifierInfo *Id) { 127 // The third "scope" argument is 0 since we aren't enabling lazy built-in 128 // creation from this context. 129 Decl *IDecl = LookupDecl(Id, Decl::IDNS_Ordinary, 0, false); 130 131 return dyn_cast_or_null<ObjCInterfaceDecl>(IDecl); 132} 133 134/// LookupDecl - Look up the inner-most declaration in the specified 135/// namespace. 136Decl *Sema::LookupDecl(const IdentifierInfo *II, unsigned NSI, 137 Scope *S, bool enableLazyBuiltinCreation) { 138 if (II == 0) return 0; 139 unsigned NS = NSI; 140 if (getLangOptions().CPlusPlus && (NS & Decl::IDNS_Ordinary)) 141 NS |= Decl::IDNS_Tag; 142 143 // Scan up the scope chain looking for a decl that matches this identifier 144 // that is in the appropriate namespace. This search should not take long, as 145 // shadowing of names is uncommon, and deep shadowing is extremely uncommon. 146 for (IdentifierResolver::iterator 147 I = IdResolver.begin(II, CurContext), E = IdResolver.end(II); I != E; ++I) 148 if ((*I)->getIdentifierNamespace() & NS) 149 return *I; 150 151 // If we didn't find a use of this identifier, and if the identifier 152 // corresponds to a compiler builtin, create the decl object for the builtin 153 // now, injecting it into translation unit scope, and return it. 154 if (NS & Decl::IDNS_Ordinary) { 155 if (enableLazyBuiltinCreation) { 156 // If this is a builtin on this (or all) targets, create the decl. 157 if (unsigned BuiltinID = II->getBuiltinID()) 158 return LazilyCreateBuiltin((IdentifierInfo *)II, BuiltinID, S); 159 } 160 if (getLangOptions().ObjC1) { 161 // @interface and @compatibility_alias introduce typedef-like names. 162 // Unlike typedef's, they can only be introduced at file-scope (and are 163 // therefore not scoped decls). They can, however, be shadowed by 164 // other names in IDNS_Ordinary. 165 ObjCInterfaceDeclsTy::iterator IDI = ObjCInterfaceDecls.find(II); 166 if (IDI != ObjCInterfaceDecls.end()) 167 return IDI->second; 168 ObjCAliasTy::iterator I = ObjCAliasDecls.find(II); 169 if (I != ObjCAliasDecls.end()) 170 return I->second->getClassInterface(); 171 } 172 } 173 return 0; 174} 175 176void Sema::InitBuiltinVaListType() { 177 if (!Context.getBuiltinVaListType().isNull()) 178 return; 179 180 IdentifierInfo *VaIdent = &Context.Idents.get("__builtin_va_list"); 181 Decl *VaDecl = LookupDecl(VaIdent, Decl::IDNS_Ordinary, TUScope); 182 TypedefDecl *VaTypedef = cast<TypedefDecl>(VaDecl); 183 Context.setBuiltinVaListType(Context.getTypedefType(VaTypedef)); 184} 185 186/// LazilyCreateBuiltin - The specified Builtin-ID was first used at file scope. 187/// lazily create a decl for it. 188ScopedDecl *Sema::LazilyCreateBuiltin(IdentifierInfo *II, unsigned bid, 189 Scope *S) { 190 Builtin::ID BID = (Builtin::ID)bid; 191 192 if (BID == Builtin::BI__builtin_va_start || 193 BID == Builtin::BI__builtin_va_copy || 194 BID == Builtin::BI__builtin_va_end) 195 InitBuiltinVaListType(); 196 197 QualType R = Context.BuiltinInfo.GetBuiltinType(BID, Context); 198 FunctionDecl *New = FunctionDecl::Create(Context, 199 Context.getTranslationUnitDecl(), 200 SourceLocation(), II, R, 201 FunctionDecl::Extern, false, 0); 202 203 // Create Decl objects for each parameter, adding them to the 204 // FunctionDecl. 205 if (FunctionTypeProto *FT = dyn_cast<FunctionTypeProto>(R)) { 206 llvm::SmallVector<ParmVarDecl*, 16> Params; 207 for (unsigned i = 0, e = FT->getNumArgs(); i != e; ++i) 208 Params.push_back(ParmVarDecl::Create(Context, New, SourceLocation(), 0, 209 FT->getArgType(i), VarDecl::None, 0, 210 0)); 211 New->setParams(&Params[0], Params.size()); 212 } 213 214 215 216 // TUScope is the translation-unit scope to insert this function into. 217 PushOnScopeChains(New, TUScope); 218 return New; 219} 220 221/// MergeTypeDefDecl - We just parsed a typedef 'New' which has the same name 222/// and scope as a previous declaration 'Old'. Figure out how to resolve this 223/// situation, merging decls or emitting diagnostics as appropriate. 224/// 225TypedefDecl *Sema::MergeTypeDefDecl(TypedefDecl *New, Decl *OldD) { 226 // Verify the old decl was also a typedef. 227 TypedefDecl *Old = dyn_cast<TypedefDecl>(OldD); 228 if (!Old) { 229 Diag(New->getLocation(), diag::err_redefinition_different_kind, 230 New->getName()); 231 Diag(OldD->getLocation(), diag::err_previous_definition); 232 return New; 233 } 234 235 // Allow multiple definitions for ObjC built-in typedefs. 236 // FIXME: Verify the underlying types are equivalent! 237 if (getLangOptions().ObjC1 && isBuiltinObjCType(New)) 238 return Old; 239 240 // Redeclaration of a type is a constraint violation (6.7.2.3p1). 241 // Apparently GCC, Intel, and Sun all silently ignore the redeclaration if 242 // *either* declaration is in a system header. The code below implements 243 // this adhoc compatibility rule. FIXME: The following code will not 244 // work properly when compiling ".i" files (containing preprocessed output). 245 SourceManager &SrcMgr = Context.getSourceManager(); 246 const FileEntry *OldDeclFile = SrcMgr.getFileEntryForLoc(Old->getLocation()); 247 const FileEntry *NewDeclFile = SrcMgr.getFileEntryForLoc(New->getLocation()); 248 HeaderSearch &HdrInfo = PP.getHeaderSearchInfo(); 249 DirectoryLookup::DirType OldDirType = HdrInfo.getFileDirFlavor(OldDeclFile); 250 DirectoryLookup::DirType NewDirType = HdrInfo.getFileDirFlavor(NewDeclFile); 251 252 // Allow reclarations in both SystemHeaderDir and ExternCSystemHeaderDir. 253 if ((OldDirType != DirectoryLookup::NormalHeaderDir || 254 NewDirType != DirectoryLookup::NormalHeaderDir) || 255 getLangOptions().Microsoft) 256 return New; 257 258 // TODO: CHECK FOR CONFLICTS, multiple decls with same name in one scope. 259 // TODO: This is totally simplistic. It should handle merging functions 260 // together etc, merging extern int X; int X; ... 261 Diag(New->getLocation(), diag::err_redefinition, New->getName()); 262 Diag(Old->getLocation(), diag::err_previous_definition); 263 return New; 264} 265 266/// DeclhasAttr - returns true if decl Declaration already has the target attribute. 267static bool DeclHasAttr(const Decl *decl, const Attr *target) { 268 for (const Attr *attr = decl->getAttrs(); attr; attr = attr->getNext()) 269 if (attr->getKind() == target->getKind()) 270 return true; 271 272 return false; 273} 274 275/// MergeAttributes - append attributes from the Old decl to the New one. 276static void MergeAttributes(Decl *New, Decl *Old) { 277 Attr *attr = const_cast<Attr*>(Old->getAttrs()), *tmp; 278 279 while (attr) { 280 tmp = attr; 281 attr = attr->getNext(); 282 283 if (!DeclHasAttr(New, tmp)) { 284 New->addAttr(tmp); 285 } else { 286 tmp->setNext(0); 287 delete(tmp); 288 } 289 } 290 291 Old->invalidateAttrs(); 292} 293 294/// MergeFunctionDecl - We just parsed a function 'New' from 295/// declarator D which has the same name and scope as a previous 296/// declaration 'Old'. Figure out how to resolve this situation, 297/// merging decls or emitting diagnostics as appropriate. 298/// Redeclaration will be set true if thisNew is a redeclaration OldD. 299FunctionDecl * 300Sema::MergeFunctionDecl(FunctionDecl *New, Decl *OldD, bool &Redeclaration) { 301 Redeclaration = false; 302 // Verify the old decl was also a function. 303 FunctionDecl *Old = dyn_cast<FunctionDecl>(OldD); 304 if (!Old) { 305 Diag(New->getLocation(), diag::err_redefinition_different_kind, 306 New->getName()); 307 Diag(OldD->getLocation(), diag::err_previous_definition); 308 return New; 309 } 310 311 QualType OldQType = Context.getCanonicalType(Old->getType()); 312 QualType NewQType = Context.getCanonicalType(New->getType()); 313 314 // C++ [dcl.fct]p3: 315 // All declarations for a function shall agree exactly in both the 316 // return type and the parameter-type-list. 317 if (getLangOptions().CPlusPlus && OldQType == NewQType) { 318 MergeAttributes(New, Old); 319 Redeclaration = true; 320 return MergeCXXFunctionDecl(New, Old); 321 } 322 323 // C: Function types need to be compatible, not identical. This handles 324 // duplicate function decls like "void f(int); void f(enum X);" properly. 325 if (!getLangOptions().CPlusPlus && 326 Context.functionTypesAreCompatible(OldQType, NewQType)) { 327 MergeAttributes(New, Old); 328 Redeclaration = true; 329 return New; 330 } 331 332 // A function that has already been declared has been redeclared or defined 333 // with a different type- show appropriate diagnostic 334 diag::kind PrevDiag; 335 if (Old->isThisDeclarationADefinition()) 336 PrevDiag = diag::err_previous_definition; 337 else if (Old->isImplicit()) 338 PrevDiag = diag::err_previous_implicit_declaration; 339 else 340 PrevDiag = diag::err_previous_declaration; 341 342 // TODO: CHECK FOR CONFLICTS, multiple decls with same name in one scope. 343 // TODO: This is totally simplistic. It should handle merging functions 344 // together etc, merging extern int X; int X; ... 345 Diag(New->getLocation(), diag::err_conflicting_types, New->getName()); 346 Diag(Old->getLocation(), PrevDiag); 347 return New; 348} 349 350/// equivalentArrayTypes - Used to determine whether two array types are 351/// equivalent. 352/// We need to check this explicitly as an incomplete array definition is 353/// considered a VariableArrayType, so will not match a complete array 354/// definition that would be otherwise equivalent. 355static bool areEquivalentArrayTypes(QualType NewQType, QualType OldQType) { 356 const ArrayType *NewAT = NewQType->getAsArrayType(); 357 const ArrayType *OldAT = OldQType->getAsArrayType(); 358 359 if (!NewAT || !OldAT) 360 return false; 361 362 // If either (or both) array types in incomplete we need to strip off the 363 // outer VariableArrayType. Once the outer VAT is removed the remaining 364 // types must be identical if the array types are to be considered 365 // equivalent. 366 // eg. int[][1] and int[1][1] become 367 // VAT(null, CAT(1, int)) and CAT(1, CAT(1, int)) 368 // removing the outermost VAT gives 369 // CAT(1, int) and CAT(1, int) 370 // which are equal, therefore the array types are equivalent. 371 if (NewAT->isIncompleteArrayType() || OldAT->isIncompleteArrayType()) { 372 if (NewAT->getIndexTypeQualifier() != OldAT->getIndexTypeQualifier()) 373 return false; 374 NewQType = NewAT->getElementType().getCanonicalType(); 375 OldQType = OldAT->getElementType().getCanonicalType(); 376 } 377 378 return NewQType == OldQType; 379} 380 381/// MergeVarDecl - We just parsed a variable 'New' which has the same name 382/// and scope as a previous declaration 'Old'. Figure out how to resolve this 383/// situation, merging decls or emitting diagnostics as appropriate. 384/// 385/// FIXME: Need to carefully consider tentative definition rules (C99 6.9.2p2). 386/// For example, we incorrectly complain about i1, i4 from C99 6.9.2p4. 387/// 388VarDecl *Sema::MergeVarDecl(VarDecl *New, Decl *OldD) { 389 // Verify the old decl was also a variable. 390 VarDecl *Old = dyn_cast<VarDecl>(OldD); 391 if (!Old) { 392 Diag(New->getLocation(), diag::err_redefinition_different_kind, 393 New->getName()); 394 Diag(OldD->getLocation(), diag::err_previous_definition); 395 return New; 396 } 397 398 MergeAttributes(New, Old); 399 400 // Verify the types match. 401 QualType OldCType = Context.getCanonicalType(Old->getType()); 402 QualType NewCType = Context.getCanonicalType(New->getType()); 403 if (OldCType != NewCType && !areEquivalentArrayTypes(NewCType, OldCType)) { 404 Diag(New->getLocation(), diag::err_redefinition, New->getName()); 405 Diag(Old->getLocation(), diag::err_previous_definition); 406 return New; 407 } 408 // C99 6.2.2p4: Check if we have a static decl followed by a non-static. 409 if (New->getStorageClass() == VarDecl::Static && 410 (Old->getStorageClass() == VarDecl::None || 411 Old->getStorageClass() == VarDecl::Extern)) { 412 Diag(New->getLocation(), diag::err_static_non_static, New->getName()); 413 Diag(Old->getLocation(), diag::err_previous_definition); 414 return New; 415 } 416 // C99 6.2.2p4: Check if we have a non-static decl followed by a static. 417 if (New->getStorageClass() != VarDecl::Static && 418 Old->getStorageClass() == VarDecl::Static) { 419 Diag(New->getLocation(), diag::err_non_static_static, New->getName()); 420 Diag(Old->getLocation(), diag::err_previous_definition); 421 return New; 422 } 423 // We've verified the types match, now handle "tentative" definitions. 424 if (Old->isFileVarDecl() && New->isFileVarDecl()) { 425 // Handle C "tentative" external object definitions (C99 6.9.2). 426 bool OldIsTentative = false; 427 bool NewIsTentative = false; 428 429 if (!Old->getInit() && 430 (Old->getStorageClass() == VarDecl::None || 431 Old->getStorageClass() == VarDecl::Static)) 432 OldIsTentative = true; 433 434 // FIXME: this check doesn't work (since the initializer hasn't been 435 // attached yet). This check should be moved to FinalizeDeclaratorGroup. 436 // Unfortunately, by the time we get to FinializeDeclaratorGroup, we've 437 // thrown out the old decl. 438 if (!New->getInit() && 439 (New->getStorageClass() == VarDecl::None || 440 New->getStorageClass() == VarDecl::Static)) 441 ; // change to NewIsTentative = true; once the code is moved. 442 443 if (NewIsTentative || OldIsTentative) 444 return New; 445 } 446 // Handle __private_extern__ just like extern. 447 if (Old->getStorageClass() != VarDecl::Extern && 448 Old->getStorageClass() != VarDecl::PrivateExtern && 449 New->getStorageClass() != VarDecl::Extern && 450 New->getStorageClass() != VarDecl::PrivateExtern) { 451 Diag(New->getLocation(), diag::err_redefinition, New->getName()); 452 Diag(Old->getLocation(), diag::err_previous_definition); 453 } 454 return New; 455} 456 457/// CheckParmsForFunctionDef - Check that the parameters of the given 458/// function are appropriate for the definition of a function. This 459/// takes care of any checks that cannot be performed on the 460/// declaration itself, e.g., that the types of each of the function 461/// parameters are complete. 462bool Sema::CheckParmsForFunctionDef(FunctionDecl *FD) { 463 bool HasInvalidParm = false; 464 for (unsigned p = 0, NumParams = FD->getNumParams(); p < NumParams; ++p) { 465 ParmVarDecl *Param = FD->getParamDecl(p); 466 467 // C99 6.7.5.3p4: the parameters in a parameter type list in a 468 // function declarator that is part of a function definition of 469 // that function shall not have incomplete type. 470 if (Param->getType()->isIncompleteType() && 471 !Param->isInvalidDecl()) { 472 Diag(Param->getLocation(), diag::err_typecheck_decl_incomplete_type, 473 Param->getType().getAsString()); 474 Param->setInvalidDecl(); 475 HasInvalidParm = true; 476 } 477 } 478 479 return HasInvalidParm; 480} 481 482/// CreateImplicitParameter - Creates an implicit function parameter 483/// in the scope S and with the given type. This routine is used, for 484/// example, to create the implicit "self" parameter in an Objective-C 485/// method. 486ParmVarDecl * 487Sema::CreateImplicitParameter(Scope *S, IdentifierInfo *Id, 488 SourceLocation IdLoc, QualType Type) { 489 ParmVarDecl *New = ParmVarDecl::Create(Context, CurContext, IdLoc, Id, Type, 490 VarDecl::None, 0, 0); 491 if (Id) 492 PushOnScopeChains(New, S); 493 494 return New; 495} 496 497/// ParsedFreeStandingDeclSpec - This method is invoked when a declspec with 498/// no declarator (e.g. "struct foo;") is parsed. 499Sema::DeclTy *Sema::ParsedFreeStandingDeclSpec(Scope *S, DeclSpec &DS) { 500 // TODO: emit error on 'int;' or 'const enum foo;'. 501 // TODO: emit error on 'typedef int;' 502 // if (!DS.isMissingDeclaratorOk()) Diag(...); 503 504 return dyn_cast_or_null<TagDecl>(static_cast<Decl *>(DS.getTypeRep())); 505} 506 507bool Sema::CheckSingleInitializer(Expr *&Init, QualType DeclType) { 508 // Get the type before calling CheckSingleAssignmentConstraints(), since 509 // it can promote the expression. 510 QualType InitType = Init->getType(); 511 512 AssignConvertType ConvTy = CheckSingleAssignmentConstraints(DeclType, Init); 513 return DiagnoseAssignmentResult(ConvTy, Init->getLocStart(), DeclType, 514 InitType, Init, "initializing"); 515} 516 517bool Sema::CheckStringLiteralInit(StringLiteral *strLiteral, QualType &DeclT) { 518 if (const IncompleteArrayType *IAT = DeclT->getAsIncompleteArrayType()) { 519 // C99 6.7.8p14. We have an array of character type with unknown size 520 // being initialized to a string literal. 521 llvm::APSInt ConstVal(32); 522 ConstVal = strLiteral->getByteLength() + 1; 523 // Return a new array type (C99 6.7.8p22). 524 DeclT = Context.getConstantArrayType(IAT->getElementType(), ConstVal, 525 ArrayType::Normal, 0); 526 } else if (const ConstantArrayType *CAT = DeclT->getAsConstantArrayType()) { 527 // C99 6.7.8p14. We have an array of character type with known size. 528 if (strLiteral->getByteLength() > (unsigned)CAT->getMaximumElements()) 529 Diag(strLiteral->getSourceRange().getBegin(), 530 diag::warn_initializer_string_for_char_array_too_long, 531 strLiteral->getSourceRange()); 532 } else { 533 assert(0 && "HandleStringLiteralInit(): Invalid array type"); 534 } 535 // Set type from "char *" to "constant array of char". 536 strLiteral->setType(DeclT); 537 // For now, we always return false (meaning success). 538 return false; 539} 540 541StringLiteral *Sema::IsStringLiteralInit(Expr *Init, QualType DeclType) { 542 const ArrayType *AT = DeclType->getAsArrayType(); 543 if (AT && AT->getElementType()->isCharType()) { 544 return dyn_cast<StringLiteral>(Init); 545 } 546 return 0; 547} 548 549bool Sema::CheckInitializerTypes(Expr *&Init, QualType &DeclType) { 550 // C99 6.7.8p3: The type of the entity to be initialized shall be an array 551 // of unknown size ("[]") or an object type that is not a variable array type. 552 if (const VariableArrayType *VAT = DeclType->getAsVariableArrayType()) 553 return Diag(VAT->getSizeExpr()->getLocStart(), 554 diag::err_variable_object_no_init, 555 VAT->getSizeExpr()->getSourceRange()); 556 557 InitListExpr *InitList = dyn_cast<InitListExpr>(Init); 558 if (!InitList) { 559 // FIXME: Handle wide strings 560 if (StringLiteral *strLiteral = IsStringLiteralInit(Init, DeclType)) 561 return CheckStringLiteralInit(strLiteral, DeclType); 562 563 if (DeclType->isArrayType()) 564 return Diag(Init->getLocStart(), 565 diag::err_array_init_list_required, 566 Init->getSourceRange()); 567 568 return CheckSingleInitializer(Init, DeclType); 569 } 570 571 InitListChecker CheckInitList(this, InitList, DeclType); 572 return CheckInitList.HadError(); 573} 574 575Sema::DeclTy * 576Sema::ActOnDeclarator(Scope *S, Declarator &D, DeclTy *lastDecl) { 577 ScopedDecl *LastDeclarator = dyn_cast_or_null<ScopedDecl>((Decl *)lastDecl); 578 IdentifierInfo *II = D.getIdentifier(); 579 580 // All of these full declarators require an identifier. If it doesn't have 581 // one, the ParsedFreeStandingDeclSpec action should be used. 582 if (II == 0) { 583 Diag(D.getDeclSpec().getSourceRange().getBegin(), 584 diag::err_declarator_need_ident, 585 D.getDeclSpec().getSourceRange(), D.getSourceRange()); 586 return 0; 587 } 588 589 // The scope passed in may not be a decl scope. Zip up the scope tree until 590 // we find one that is. 591 while ((S->getFlags() & Scope::DeclScope) == 0) 592 S = S->getParent(); 593 594 // See if this is a redefinition of a variable in the same scope. 595 Decl *PrevDecl = LookupDecl(II, Decl::IDNS_Ordinary, S); 596 ScopedDecl *New; 597 bool InvalidDecl = false; 598 599 // In C++, the previous declaration we find might be a tag type 600 // (class or enum). In this case, the new declaration will hide the 601 // tag type. 602 if (PrevDecl && PrevDecl->getIdentifierNamespace() == Decl::IDNS_Tag) 603 PrevDecl = 0; 604 605 QualType R = GetTypeForDeclarator(D, S); 606 assert(!R.isNull() && "GetTypeForDeclarator() returned null type"); 607 608 if (D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_typedef) { 609 // Check that there are no default arguments (C++ only). 610 if (getLangOptions().CPlusPlus) 611 CheckExtraCXXDefaultArguments(D); 612 613 TypedefDecl *NewTD = ParseTypedefDecl(S, D, R, LastDeclarator); 614 if (!NewTD) return 0; 615 616 // Handle attributes prior to checking for duplicates in MergeVarDecl 617 HandleDeclAttributes(NewTD, D.getDeclSpec().getAttributes(), 618 D.getAttributes()); 619 // Merge the decl with the existing one if appropriate. If the decl is 620 // in an outer scope, it isn't the same thing. 621 if (PrevDecl && IdResolver.isDeclInScope(PrevDecl, CurContext, S)) { 622 NewTD = MergeTypeDefDecl(NewTD, PrevDecl); 623 if (NewTD == 0) return 0; 624 } 625 New = NewTD; 626 if (S->getFnParent() == 0) { 627 // C99 6.7.7p2: If a typedef name specifies a variably modified type 628 // then it shall have block scope. 629 if (NewTD->getUnderlyingType()->isVariablyModifiedType()) { 630 // FIXME: Diagnostic needs to be fixed. 631 Diag(D.getIdentifierLoc(), diag::err_typecheck_illegal_vla); 632 InvalidDecl = true; 633 } 634 } 635 } else if (R.getTypePtr()->isFunctionType()) { 636 FunctionDecl::StorageClass SC = FunctionDecl::None; 637 switch (D.getDeclSpec().getStorageClassSpec()) { 638 default: assert(0 && "Unknown storage class!"); 639 case DeclSpec::SCS_auto: 640 case DeclSpec::SCS_register: 641 Diag(D.getIdentifierLoc(), diag::err_typecheck_sclass_func, 642 R.getAsString()); 643 InvalidDecl = true; 644 break; 645 case DeclSpec::SCS_unspecified: SC = FunctionDecl::None; break; 646 case DeclSpec::SCS_extern: SC = FunctionDecl::Extern; break; 647 case DeclSpec::SCS_static: SC = FunctionDecl::Static; break; 648 case DeclSpec::SCS_private_extern: SC = FunctionDecl::PrivateExtern;break; 649 } 650 651 bool isInline = D.getDeclSpec().isInlineSpecified(); 652 FunctionDecl *NewFD = FunctionDecl::Create(Context, CurContext, 653 D.getIdentifierLoc(), 654 II, R, SC, isInline, 655 LastDeclarator); 656 // Handle attributes. 657 HandleDeclAttributes(NewFD, D.getDeclSpec().getAttributes(), 658 D.getAttributes()); 659 660 // Copy the parameter declarations from the declarator D to 661 // the function declaration NewFD, if they are available. 662 if (D.getNumTypeObjects() > 0 && 663 D.getTypeObject(0).Fun.hasPrototype) { 664 DeclaratorChunk::FunctionTypeInfo &FTI = D.getTypeObject(0).Fun; 665 666 // Create Decl objects for each parameter, adding them to the 667 // FunctionDecl. 668 llvm::SmallVector<ParmVarDecl*, 16> Params; 669 670 // Check for C99 6.7.5.3p10 - foo(void) is a non-varargs 671 // function that takes no arguments, not a function that takes a 672 // single void argument. 673 // We let through "const void" here because Sema::GetTypeForDeclarator 674 // already checks for that case. 675 if (FTI.NumArgs == 1 && !FTI.isVariadic && FTI.ArgInfo[0].Ident == 0 && 676 FTI.ArgInfo[0].Param && 677 ((ParmVarDecl*)FTI.ArgInfo[0].Param)->getType()->isVoidType()) { 678 // empty arg list, don't push any params. 679 ParmVarDecl *Param = (ParmVarDecl*)FTI.ArgInfo[0].Param; 680 681 // In C++, the empty parameter-type-list must be spelled "void"; a 682 // typedef of void is not permitted. 683 if (getLangOptions().CPlusPlus && 684 Param->getType().getUnqualifiedType() != Context.VoidTy) { 685 Diag(Param->getLocation(), diag::ext_param_typedef_of_void); 686 } 687 688 } else { 689 for (unsigned i = 0, e = FTI.NumArgs; i != e; ++i) 690 Params.push_back((ParmVarDecl *)FTI.ArgInfo[i].Param); 691 } 692 693 NewFD->setParams(&Params[0], Params.size()); 694 } 695 696 // Merge the decl with the existing one if appropriate. Since C functions 697 // are in a flat namespace, make sure we consider decls in outer scopes. 698 if (PrevDecl && 699 (!getLangOptions().CPlusPlus || 700 IdResolver.isDeclInScope(PrevDecl, CurContext, S)) ) { 701 bool Redeclaration = false; 702 NewFD = MergeFunctionDecl(NewFD, PrevDecl, Redeclaration); 703 if (NewFD == 0) return 0; 704 if (Redeclaration) { 705 NewFD->setPreviousDeclaration(cast<FunctionDecl>(PrevDecl)); 706 } 707 } 708 New = NewFD; 709 710 // In C++, check default arguments now that we have merged decls. 711 if (getLangOptions().CPlusPlus) 712 CheckCXXDefaultArguments(NewFD); 713 } else { 714 // Check that there are no default arguments (C++ only). 715 if (getLangOptions().CPlusPlus) 716 CheckExtraCXXDefaultArguments(D); 717 718 if (R.getTypePtr()->isObjCInterfaceType()) { 719 Diag(D.getIdentifierLoc(), diag::err_statically_allocated_object, 720 D.getIdentifier()->getName()); 721 InvalidDecl = true; 722 } 723 724 VarDecl *NewVD; 725 VarDecl::StorageClass SC; 726 switch (D.getDeclSpec().getStorageClassSpec()) { 727 default: assert(0 && "Unknown storage class!"); 728 case DeclSpec::SCS_unspecified: SC = VarDecl::None; break; 729 case DeclSpec::SCS_extern: SC = VarDecl::Extern; break; 730 case DeclSpec::SCS_static: SC = VarDecl::Static; break; 731 case DeclSpec::SCS_auto: SC = VarDecl::Auto; break; 732 case DeclSpec::SCS_register: SC = VarDecl::Register; break; 733 case DeclSpec::SCS_private_extern: SC = VarDecl::PrivateExtern; break; 734 } 735 if (S->getFnParent() == 0) { 736 // C99 6.9p2: The storage-class specifiers auto and register shall not 737 // appear in the declaration specifiers in an external declaration. 738 if (SC == VarDecl::Auto || SC == VarDecl::Register) { 739 Diag(D.getIdentifierLoc(), diag::err_typecheck_sclass_fscope, 740 R.getAsString()); 741 InvalidDecl = true; 742 } 743 NewVD = VarDecl::Create(Context, CurContext, D.getIdentifierLoc(), 744 II, R, SC, LastDeclarator); 745 } else { 746 NewVD = VarDecl::Create(Context, CurContext, D.getIdentifierLoc(), 747 II, R, SC, LastDeclarator); 748 } 749 // Handle attributes prior to checking for duplicates in MergeVarDecl 750 HandleDeclAttributes(NewVD, D.getDeclSpec().getAttributes(), 751 D.getAttributes()); 752 753 // Emit an error if an address space was applied to decl with local storage. 754 // This includes arrays of objects with address space qualifiers, but not 755 // automatic variables that point to other address spaces. 756 // ISO/IEC TR 18037 S5.1.2 757 if (NewVD->hasLocalStorage() && (NewVD->getType().getAddressSpace() != 0)) { 758 Diag(D.getIdentifierLoc(), diag::err_as_qualified_auto_decl); 759 InvalidDecl = true; 760 } 761 // Merge the decl with the existing one if appropriate. If the decl is 762 // in an outer scope, it isn't the same thing. 763 if (PrevDecl && IdResolver.isDeclInScope(PrevDecl, CurContext, S)) { 764 NewVD = MergeVarDecl(NewVD, PrevDecl); 765 if (NewVD == 0) return 0; 766 } 767 New = NewVD; 768 } 769 770 // If this has an identifier, add it to the scope stack. 771 if (II) 772 PushOnScopeChains(New, S); 773 // If any semantic error occurred, mark the decl as invalid. 774 if (D.getInvalidType() || InvalidDecl) 775 New->setInvalidDecl(); 776 777 return New; 778} 779 780bool Sema::CheckAddressConstantExpressionLValue(const Expr* Init) { 781 switch (Init->getStmtClass()) { 782 default: 783 Diag(Init->getExprLoc(), 784 diag::err_init_element_not_constant, Init->getSourceRange()); 785 return true; 786 case Expr::ParenExprClass: { 787 const ParenExpr* PE = cast<ParenExpr>(Init); 788 return CheckAddressConstantExpressionLValue(PE->getSubExpr()); 789 } 790 case Expr::CompoundLiteralExprClass: 791 return cast<CompoundLiteralExpr>(Init)->isFileScope(); 792 case Expr::DeclRefExprClass: { 793 const Decl *D = cast<DeclRefExpr>(Init)->getDecl(); 794 if (const VarDecl *VD = dyn_cast<VarDecl>(D)) { 795 if (VD->hasGlobalStorage()) 796 return false; 797 Diag(Init->getExprLoc(), 798 diag::err_init_element_not_constant, Init->getSourceRange()); 799 return true; 800 } 801 if (isa<FunctionDecl>(D)) 802 return false; 803 Diag(Init->getExprLoc(), 804 diag::err_init_element_not_constant, Init->getSourceRange()); 805 return true; 806 } 807 case Expr::MemberExprClass: { 808 const MemberExpr *M = cast<MemberExpr>(Init); 809 if (M->isArrow()) 810 return CheckAddressConstantExpression(M->getBase()); 811 return CheckAddressConstantExpressionLValue(M->getBase()); 812 } 813 case Expr::ArraySubscriptExprClass: { 814 // FIXME: Should we pedwarn for "x[0+0]" (where x is a pointer)? 815 const ArraySubscriptExpr *ASE = cast<ArraySubscriptExpr>(Init); 816 return CheckAddressConstantExpression(ASE->getBase()) || 817 CheckArithmeticConstantExpression(ASE->getIdx()); 818 } 819 case Expr::StringLiteralClass: 820 case Expr::PreDefinedExprClass: 821 return false; 822 case Expr::UnaryOperatorClass: { 823 const UnaryOperator *Exp = cast<UnaryOperator>(Init); 824 825 // C99 6.6p9 826 if (Exp->getOpcode() == UnaryOperator::Deref) 827 return CheckAddressConstantExpression(Exp->getSubExpr()); 828 829 Diag(Init->getExprLoc(), 830 diag::err_init_element_not_constant, Init->getSourceRange()); 831 return true; 832 } 833 } 834} 835 836bool Sema::CheckAddressConstantExpression(const Expr* Init) { 837 switch (Init->getStmtClass()) { 838 default: 839 Diag(Init->getExprLoc(), 840 diag::err_init_element_not_constant, Init->getSourceRange()); 841 return true; 842 case Expr::ParenExprClass: { 843 const ParenExpr* PE = cast<ParenExpr>(Init); 844 return CheckAddressConstantExpression(PE->getSubExpr()); 845 } 846 case Expr::StringLiteralClass: 847 case Expr::ObjCStringLiteralClass: 848 return false; 849 case Expr::CallExprClass: { 850 const CallExpr *CE = cast<CallExpr>(Init); 851 if (CE->isBuiltinConstantExpr()) 852 return false; 853 Diag(Init->getExprLoc(), 854 diag::err_init_element_not_constant, Init->getSourceRange()); 855 return true; 856 } 857 case Expr::UnaryOperatorClass: { 858 const UnaryOperator *Exp = cast<UnaryOperator>(Init); 859 860 // C99 6.6p9 861 if (Exp->getOpcode() == UnaryOperator::AddrOf) 862 return CheckAddressConstantExpressionLValue(Exp->getSubExpr()); 863 864 if (Exp->getOpcode() == UnaryOperator::Extension) 865 return CheckAddressConstantExpression(Exp->getSubExpr()); 866 867 Diag(Init->getExprLoc(), 868 diag::err_init_element_not_constant, Init->getSourceRange()); 869 return true; 870 } 871 case Expr::BinaryOperatorClass: { 872 // FIXME: Should we pedwarn for expressions like "a + 1 + 2"? 873 const BinaryOperator *Exp = cast<BinaryOperator>(Init); 874 875 Expr *PExp = Exp->getLHS(); 876 Expr *IExp = Exp->getRHS(); 877 if (IExp->getType()->isPointerType()) 878 std::swap(PExp, IExp); 879 880 // FIXME: Should we pedwarn if IExp isn't an integer constant expression? 881 return CheckAddressConstantExpression(PExp) || 882 CheckArithmeticConstantExpression(IExp); 883 } 884 case Expr::ImplicitCastExprClass: { 885 const Expr* SubExpr = cast<ImplicitCastExpr>(Init)->getSubExpr(); 886 887 // Check for implicit promotion 888 if (SubExpr->getType()->isFunctionType() || 889 SubExpr->getType()->isArrayType()) 890 return CheckAddressConstantExpressionLValue(SubExpr); 891 892 // Check for pointer->pointer cast 893 if (SubExpr->getType()->isPointerType()) 894 return CheckAddressConstantExpression(SubExpr); 895 896 if (SubExpr->getType()->isArithmeticType()) 897 return CheckArithmeticConstantExpression(SubExpr); 898 899 Diag(Init->getExprLoc(), 900 diag::err_init_element_not_constant, Init->getSourceRange()); 901 return true; 902 } 903 case Expr::CastExprClass: { 904 const Expr* SubExpr = cast<CastExpr>(Init)->getSubExpr(); 905 906 // Check for pointer->pointer cast 907 if (SubExpr->getType()->isPointerType()) 908 return CheckAddressConstantExpression(SubExpr); 909 910 // FIXME: Should we pedwarn for (int*)(0+0)? 911 if (SubExpr->getType()->isArithmeticType()) 912 return CheckArithmeticConstantExpression(SubExpr); 913 914 Diag(Init->getExprLoc(), 915 diag::err_init_element_not_constant, Init->getSourceRange()); 916 return true; 917 } 918 case Expr::ConditionalOperatorClass: { 919 // FIXME: Should we pedwarn here? 920 const ConditionalOperator *Exp = cast<ConditionalOperator>(Init); 921 if (!Exp->getCond()->getType()->isArithmeticType()) { 922 Diag(Init->getExprLoc(), 923 diag::err_init_element_not_constant, Init->getSourceRange()); 924 return true; 925 } 926 if (CheckArithmeticConstantExpression(Exp->getCond())) 927 return true; 928 if (Exp->getLHS() && 929 CheckAddressConstantExpression(Exp->getLHS())) 930 return true; 931 return CheckAddressConstantExpression(Exp->getRHS()); 932 } 933 case Expr::AddrLabelExprClass: 934 return false; 935 } 936} 937 938static const Expr* FindExpressionBaseAddress(const Expr* E); 939 940static const Expr* FindExpressionBaseAddressLValue(const Expr* E) { 941 switch (E->getStmtClass()) { 942 default: 943 return E; 944 case Expr::ParenExprClass: { 945 const ParenExpr* PE = cast<ParenExpr>(E); 946 return FindExpressionBaseAddressLValue(PE->getSubExpr()); 947 } 948 case Expr::MemberExprClass: { 949 const MemberExpr *M = cast<MemberExpr>(E); 950 if (M->isArrow()) 951 return FindExpressionBaseAddress(M->getBase()); 952 return FindExpressionBaseAddressLValue(M->getBase()); 953 } 954 case Expr::ArraySubscriptExprClass: { 955 const ArraySubscriptExpr *ASE = cast<ArraySubscriptExpr>(E); 956 return FindExpressionBaseAddress(ASE->getBase()); 957 } 958 case Expr::UnaryOperatorClass: { 959 const UnaryOperator *Exp = cast<UnaryOperator>(E); 960 961 if (Exp->getOpcode() == UnaryOperator::Deref) 962 return FindExpressionBaseAddress(Exp->getSubExpr()); 963 964 return E; 965 } 966 } 967} 968 969static const Expr* FindExpressionBaseAddress(const Expr* E) { 970 switch (E->getStmtClass()) { 971 default: 972 return E; 973 case Expr::ParenExprClass: { 974 const ParenExpr* PE = cast<ParenExpr>(E); 975 return FindExpressionBaseAddress(PE->getSubExpr()); 976 } 977 case Expr::UnaryOperatorClass: { 978 const UnaryOperator *Exp = cast<UnaryOperator>(E); 979 980 // C99 6.6p9 981 if (Exp->getOpcode() == UnaryOperator::AddrOf) 982 return FindExpressionBaseAddressLValue(Exp->getSubExpr()); 983 984 if (Exp->getOpcode() == UnaryOperator::Extension) 985 return FindExpressionBaseAddress(Exp->getSubExpr()); 986 987 return E; 988 } 989 case Expr::BinaryOperatorClass: { 990 const BinaryOperator *Exp = cast<BinaryOperator>(E); 991 992 Expr *PExp = Exp->getLHS(); 993 Expr *IExp = Exp->getRHS(); 994 if (IExp->getType()->isPointerType()) 995 std::swap(PExp, IExp); 996 997 return FindExpressionBaseAddress(PExp); 998 } 999 case Expr::ImplicitCastExprClass: { 1000 const Expr* SubExpr = cast<ImplicitCastExpr>(E)->getSubExpr(); 1001 1002 // Check for implicit promotion 1003 if (SubExpr->getType()->isFunctionType() || 1004 SubExpr->getType()->isArrayType()) 1005 return FindExpressionBaseAddressLValue(SubExpr); 1006 1007 // Check for pointer->pointer cast 1008 if (SubExpr->getType()->isPointerType()) 1009 return FindExpressionBaseAddress(SubExpr); 1010 1011 // We assume that we have an arithmetic expression here; 1012 // if we don't, we'll figure it out later 1013 return 0; 1014 } 1015 case Expr::CastExprClass: { 1016 const Expr* SubExpr = cast<CastExpr>(E)->getSubExpr(); 1017 1018 // Check for pointer->pointer cast 1019 if (SubExpr->getType()->isPointerType()) 1020 return FindExpressionBaseAddress(SubExpr); 1021 1022 // We assume that we have an arithmetic expression here; 1023 // if we don't, we'll figure it out later 1024 return 0; 1025 } 1026 } 1027} 1028 1029bool Sema::CheckArithmeticConstantExpression(const Expr* Init) { 1030 switch (Init->getStmtClass()) { 1031 default: 1032 Diag(Init->getExprLoc(), 1033 diag::err_init_element_not_constant, Init->getSourceRange()); 1034 return true; 1035 case Expr::ParenExprClass: { 1036 const ParenExpr* PE = cast<ParenExpr>(Init); 1037 return CheckArithmeticConstantExpression(PE->getSubExpr()); 1038 } 1039 case Expr::FloatingLiteralClass: 1040 case Expr::IntegerLiteralClass: 1041 case Expr::CharacterLiteralClass: 1042 case Expr::ImaginaryLiteralClass: 1043 case Expr::TypesCompatibleExprClass: 1044 case Expr::CXXBoolLiteralExprClass: 1045 return false; 1046 case Expr::CallExprClass: { 1047 const CallExpr *CE = cast<CallExpr>(Init); 1048 if (CE->isBuiltinConstantExpr()) 1049 return false; 1050 Diag(Init->getExprLoc(), 1051 diag::err_init_element_not_constant, Init->getSourceRange()); 1052 return true; 1053 } 1054 case Expr::DeclRefExprClass: { 1055 const Decl *D = cast<DeclRefExpr>(Init)->getDecl(); 1056 if (isa<EnumConstantDecl>(D)) 1057 return false; 1058 Diag(Init->getExprLoc(), 1059 diag::err_init_element_not_constant, Init->getSourceRange()); 1060 return true; 1061 } 1062 case Expr::CompoundLiteralExprClass: 1063 // Allow "(vector type){2,4}"; normal C constraints don't allow this, 1064 // but vectors are allowed to be magic. 1065 if (Init->getType()->isVectorType()) 1066 return false; 1067 Diag(Init->getExprLoc(), 1068 diag::err_init_element_not_constant, Init->getSourceRange()); 1069 return true; 1070 case Expr::UnaryOperatorClass: { 1071 const UnaryOperator *Exp = cast<UnaryOperator>(Init); 1072 1073 switch (Exp->getOpcode()) { 1074 // Address, indirect, pre/post inc/dec, etc are not valid constant exprs. 1075 // See C99 6.6p3. 1076 default: 1077 Diag(Init->getExprLoc(), 1078 diag::err_init_element_not_constant, Init->getSourceRange()); 1079 return true; 1080 case UnaryOperator::SizeOf: 1081 case UnaryOperator::AlignOf: 1082 case UnaryOperator::OffsetOf: 1083 // sizeof(E) is a constantexpr if and only if E is not evaluted. 1084 // See C99 6.5.3.4p2 and 6.6p3. 1085 if (Exp->getSubExpr()->getType()->isConstantSizeType()) 1086 return false; 1087 Diag(Init->getExprLoc(), 1088 diag::err_init_element_not_constant, Init->getSourceRange()); 1089 return true; 1090 case UnaryOperator::Extension: 1091 case UnaryOperator::LNot: 1092 case UnaryOperator::Plus: 1093 case UnaryOperator::Minus: 1094 case UnaryOperator::Not: 1095 return CheckArithmeticConstantExpression(Exp->getSubExpr()); 1096 } 1097 } 1098 case Expr::SizeOfAlignOfTypeExprClass: { 1099 const SizeOfAlignOfTypeExpr *Exp = cast<SizeOfAlignOfTypeExpr>(Init); 1100 // Special check for void types, which are allowed as an extension 1101 if (Exp->getArgumentType()->isVoidType()) 1102 return false; 1103 // alignof always evaluates to a constant. 1104 // FIXME: is sizeof(int[3.0]) a constant expression? 1105 if (Exp->isSizeOf() && !Exp->getArgumentType()->isConstantSizeType()) { 1106 Diag(Init->getExprLoc(), 1107 diag::err_init_element_not_constant, Init->getSourceRange()); 1108 return true; 1109 } 1110 return false; 1111 } 1112 case Expr::BinaryOperatorClass: { 1113 const BinaryOperator *Exp = cast<BinaryOperator>(Init); 1114 1115 if (Exp->getLHS()->getType()->isArithmeticType() && 1116 Exp->getRHS()->getType()->isArithmeticType()) { 1117 return CheckArithmeticConstantExpression(Exp->getLHS()) || 1118 CheckArithmeticConstantExpression(Exp->getRHS()); 1119 } 1120 1121 if (Exp->getLHS()->getType()->isPointerType() && 1122 Exp->getRHS()->getType()->isPointerType()) { 1123 const Expr* LHSBase = FindExpressionBaseAddress(Exp->getLHS()); 1124 const Expr* RHSBase = FindExpressionBaseAddress(Exp->getRHS()); 1125 1126 // Only allow a null (constant integer) base; we could 1127 // allow some additional cases if necessary, but this 1128 // is sufficient to cover offsetof-like constructs. 1129 if (!LHSBase && !RHSBase) { 1130 return CheckAddressConstantExpression(Exp->getLHS()) || 1131 CheckAddressConstantExpression(Exp->getRHS()); 1132 } 1133 } 1134 1135 Diag(Init->getExprLoc(), 1136 diag::err_init_element_not_constant, Init->getSourceRange()); 1137 return true; 1138 } 1139 case Expr::ImplicitCastExprClass: 1140 case Expr::CastExprClass: { 1141 const Expr *SubExpr; 1142 if (const CastExpr *C = dyn_cast<CastExpr>(Init)) { 1143 SubExpr = C->getSubExpr(); 1144 } else { 1145 SubExpr = cast<ImplicitCastExpr>(Init)->getSubExpr(); 1146 } 1147 1148 if (SubExpr->getType()->isArithmeticType()) 1149 return CheckArithmeticConstantExpression(SubExpr); 1150 1151 Diag(Init->getExprLoc(), 1152 diag::err_init_element_not_constant, Init->getSourceRange()); 1153 return true; 1154 } 1155 case Expr::ConditionalOperatorClass: { 1156 const ConditionalOperator *Exp = cast<ConditionalOperator>(Init); 1157 if (CheckArithmeticConstantExpression(Exp->getCond())) 1158 return true; 1159 if (Exp->getLHS() && 1160 CheckArithmeticConstantExpression(Exp->getLHS())) 1161 return true; 1162 return CheckArithmeticConstantExpression(Exp->getRHS()); 1163 } 1164 } 1165} 1166 1167bool Sema::CheckForConstantInitializer(Expr *Init, QualType DclT) { 1168 // Look through CXXDefaultArgExprs; they have no meaning in this context. 1169 if (CXXDefaultArgExpr* DAE = dyn_cast<CXXDefaultArgExpr>(Init)) 1170 return CheckForConstantInitializer(DAE->getExpr(), DclT); 1171 1172 if (Init->getType()->isReferenceType()) { 1173 // FIXME: Work out how the heck reference types work 1174 return false; 1175#if 0 1176 // A reference is constant if the address of the expression 1177 // is constant 1178 // We look through initlists here to simplify 1179 // CheckAddressConstantExpressionLValue. 1180 if (InitListExpr *Exp = dyn_cast<InitListExpr>(Init)) { 1181 assert(Exp->getNumInits() > 0 && 1182 "Refernce initializer cannot be empty"); 1183 Init = Exp->getInit(0); 1184 } 1185 return CheckAddressConstantExpressionLValue(Init); 1186#endif 1187 } 1188 1189 if (InitListExpr *Exp = dyn_cast<InitListExpr>(Init)) { 1190 unsigned numInits = Exp->getNumInits(); 1191 for (unsigned i = 0; i < numInits; i++) { 1192 // FIXME: Need to get the type of the declaration for C++, 1193 // because it could be a reference? 1194 if (CheckForConstantInitializer(Exp->getInit(i), 1195 Exp->getInit(i)->getType())) 1196 return true; 1197 } 1198 return false; 1199 } 1200 1201 if (Init->isNullPointerConstant(Context)) 1202 return false; 1203 if (Init->getType()->isArithmeticType()) { 1204 QualType InitTy = Init->getType().getCanonicalType().getUnqualifiedType(); 1205 if (InitTy == Context.BoolTy) { 1206 // Special handling for pointers implicitly cast to bool; 1207 // (e.g. "_Bool rr = &rr;"). This is only legal at the top level. 1208 if (ImplicitCastExpr* ICE = dyn_cast<ImplicitCastExpr>(Init)) { 1209 Expr* SubE = ICE->getSubExpr(); 1210 if (SubE->getType()->isPointerType() || 1211 SubE->getType()->isArrayType() || 1212 SubE->getType()->isFunctionType()) { 1213 return CheckAddressConstantExpression(Init); 1214 } 1215 } 1216 } else if (InitTy->isIntegralType()) { 1217 Expr* SubE = 0; 1218 if (ImplicitCastExpr* ICE = dyn_cast<ImplicitCastExpr>(Init)) 1219 SubE = ICE->getSubExpr(); 1220 else if (CastExpr* CE = dyn_cast<CastExpr>(Init)) 1221 SubE = CE->getSubExpr(); 1222 // Special check for pointer cast to int; we allow as an extension 1223 // an address constant cast to an integer if the integer 1224 // is of an appropriate width (this sort of code is apparently used 1225 // in some places). 1226 // FIXME: Add pedwarn? 1227 // FIXME: Don't allow bitfields here! Need the FieldDecl for that. 1228 if (SubE && (SubE->getType()->isPointerType() || 1229 SubE->getType()->isArrayType() || 1230 SubE->getType()->isFunctionType())) { 1231 unsigned IntWidth = Context.getTypeSize(Init->getType()); 1232 unsigned PointerWidth = Context.getTypeSize(Context.VoidPtrTy); 1233 if (IntWidth >= PointerWidth) 1234 return CheckAddressConstantExpression(Init); 1235 } 1236 } 1237 1238 return CheckArithmeticConstantExpression(Init); 1239 } 1240 1241 if (Init->getType()->isPointerType()) 1242 return CheckAddressConstantExpression(Init); 1243 1244 // An array type at the top level that isn't an init-list must 1245 // be a string literal 1246 if (Init->getType()->isArrayType()) 1247 return false; 1248 1249 Diag(Init->getExprLoc(), diag::err_init_element_not_constant, 1250 Init->getSourceRange()); 1251 return true; 1252} 1253 1254void Sema::AddInitializerToDecl(DeclTy *dcl, ExprTy *init) { 1255 Decl *RealDecl = static_cast<Decl *>(dcl); 1256 Expr *Init = static_cast<Expr *>(init); 1257 assert(Init && "missing initializer"); 1258 1259 // If there is no declaration, there was an error parsing it. Just ignore 1260 // the initializer. 1261 if (RealDecl == 0) { 1262 delete Init; 1263 return; 1264 } 1265 1266 VarDecl *VDecl = dyn_cast<VarDecl>(RealDecl); 1267 if (!VDecl) { 1268 Diag(dyn_cast<ScopedDecl>(RealDecl)->getLocation(), 1269 diag::err_illegal_initializer); 1270 RealDecl->setInvalidDecl(); 1271 return; 1272 } 1273 // Get the decls type and save a reference for later, since 1274 // CheckInitializerTypes may change it. 1275 QualType DclT = VDecl->getType(), SavT = DclT; 1276 if (VDecl->isBlockVarDecl()) { 1277 VarDecl::StorageClass SC = VDecl->getStorageClass(); 1278 if (SC == VarDecl::Extern) { // C99 6.7.8p5 1279 Diag(VDecl->getLocation(), diag::err_block_extern_cant_init); 1280 VDecl->setInvalidDecl(); 1281 } else if (!VDecl->isInvalidDecl()) { 1282 if (CheckInitializerTypes(Init, DclT)) 1283 VDecl->setInvalidDecl(); 1284 if (SC == VarDecl::Static) // C99 6.7.8p4. 1285 CheckForConstantInitializer(Init, DclT); 1286 } 1287 } else if (VDecl->isFileVarDecl()) { 1288 if (VDecl->getStorageClass() == VarDecl::Extern) 1289 Diag(VDecl->getLocation(), diag::warn_extern_init); 1290 if (!VDecl->isInvalidDecl()) 1291 if (CheckInitializerTypes(Init, DclT)) 1292 VDecl->setInvalidDecl(); 1293 1294 // C99 6.7.8p4. All file scoped initializers need to be constant. 1295 CheckForConstantInitializer(Init, DclT); 1296 } 1297 // If the type changed, it means we had an incomplete type that was 1298 // completed by the initializer. For example: 1299 // int ary[] = { 1, 3, 5 }; 1300 // "ary" transitions from a VariableArrayType to a ConstantArrayType. 1301 if (!VDecl->isInvalidDecl() && (DclT != SavT)) { 1302 VDecl->setType(DclT); 1303 Init->setType(DclT); 1304 } 1305 1306 // Attach the initializer to the decl. 1307 VDecl->setInit(Init); 1308 return; 1309} 1310 1311/// The declarators are chained together backwards, reverse the list. 1312Sema::DeclTy *Sema::FinalizeDeclaratorGroup(Scope *S, DeclTy *group) { 1313 // Often we have single declarators, handle them quickly. 1314 Decl *GroupDecl = static_cast<Decl*>(group); 1315 if (GroupDecl == 0) 1316 return 0; 1317 1318 ScopedDecl *Group = dyn_cast<ScopedDecl>(GroupDecl); 1319 ScopedDecl *NewGroup = 0; 1320 if (Group->getNextDeclarator() == 0) 1321 NewGroup = Group; 1322 else { // reverse the list. 1323 while (Group) { 1324 ScopedDecl *Next = Group->getNextDeclarator(); 1325 Group->setNextDeclarator(NewGroup); 1326 NewGroup = Group; 1327 Group = Next; 1328 } 1329 } 1330 // Perform semantic analysis that depends on having fully processed both 1331 // the declarator and initializer. 1332 for (ScopedDecl *ID = NewGroup; ID; ID = ID->getNextDeclarator()) { 1333 VarDecl *IDecl = dyn_cast<VarDecl>(ID); 1334 if (!IDecl) 1335 continue; 1336 QualType T = IDecl->getType(); 1337 1338 // C99 6.7.5.2p2: If an identifier is declared to be an object with 1339 // static storage duration, it shall not have a variable length array. 1340 if ((IDecl->isFileVarDecl() || IDecl->isBlockVarDecl()) && 1341 IDecl->getStorageClass() == VarDecl::Static) { 1342 if (T->getAsVariableArrayType()) { 1343 Diag(IDecl->getLocation(), diag::err_typecheck_illegal_vla); 1344 IDecl->setInvalidDecl(); 1345 } 1346 } 1347 // Block scope. C99 6.7p7: If an identifier for an object is declared with 1348 // no linkage (C99 6.2.2p6), the type for the object shall be complete... 1349 if (IDecl->isBlockVarDecl() && 1350 IDecl->getStorageClass() != VarDecl::Extern) { 1351 if (T->isIncompleteType() && !IDecl->isInvalidDecl()) { 1352 Diag(IDecl->getLocation(), diag::err_typecheck_decl_incomplete_type, 1353 T.getAsString()); 1354 IDecl->setInvalidDecl(); 1355 } 1356 } 1357 // File scope. C99 6.9.2p2: A declaration of an identifier for and 1358 // object that has file scope without an initializer, and without a 1359 // storage-class specifier or with the storage-class specifier "static", 1360 // constitutes a tentative definition. Note: A tentative definition with 1361 // external linkage is valid (C99 6.2.2p5). 1362 if (IDecl && !IDecl->getInit() && 1363 (IDecl->getStorageClass() == VarDecl::Static || 1364 IDecl->getStorageClass() == VarDecl::None)) { 1365 if (T->isIncompleteArrayType()) { 1366 // C99 6.9.2 (p2, p5): Implicit initialization causes an incomplete 1367 // array to be completed. Don't issue a diagnostic. 1368 } else if (T->isIncompleteType() && !IDecl->isInvalidDecl()) { 1369 // C99 6.9.2p3: If the declaration of an identifier for an object is 1370 // a tentative definition and has internal linkage (C99 6.2.2p3), the 1371 // declared type shall not be an incomplete type. 1372 Diag(IDecl->getLocation(), diag::err_typecheck_decl_incomplete_type, 1373 T.getAsString()); 1374 IDecl->setInvalidDecl(); 1375 } 1376 } 1377 } 1378 return NewGroup; 1379} 1380 1381/// ActOnParamDeclarator - Called from Parser::ParseFunctionDeclarator() 1382/// to introduce parameters into function prototype scope. 1383Sema::DeclTy * 1384Sema::ActOnParamDeclarator(Scope *S, Declarator &D) { 1385 DeclSpec &DS = D.getDeclSpec(); 1386 1387 // Verify C99 6.7.5.3p2: The only SCS allowed is 'register'. 1388 if (DS.getStorageClassSpec() != DeclSpec::SCS_unspecified && 1389 DS.getStorageClassSpec() != DeclSpec::SCS_register) { 1390 Diag(DS.getStorageClassSpecLoc(), 1391 diag::err_invalid_storage_class_in_func_decl); 1392 DS.ClearStorageClassSpecs(); 1393 } 1394 if (DS.isThreadSpecified()) { 1395 Diag(DS.getThreadSpecLoc(), 1396 diag::err_invalid_storage_class_in_func_decl); 1397 DS.ClearStorageClassSpecs(); 1398 } 1399 1400 // Check that there are no default arguments inside the type of this 1401 // parameter (C++ only). 1402 if (getLangOptions().CPlusPlus) 1403 CheckExtraCXXDefaultArguments(D); 1404 1405 // In this context, we *do not* check D.getInvalidType(). If the declarator 1406 // type was invalid, GetTypeForDeclarator() still returns a "valid" type, 1407 // though it will not reflect the user specified type. 1408 QualType parmDeclType = GetTypeForDeclarator(D, S); 1409 1410 assert(!parmDeclType.isNull() && "GetTypeForDeclarator() returned null type"); 1411 1412 // TODO: CHECK FOR CONFLICTS, multiple decls with same name in one scope. 1413 // Can this happen for params? We already checked that they don't conflict 1414 // among each other. Here they can only shadow globals, which is ok. 1415 IdentifierInfo *II = D.getIdentifier(); 1416 if (Decl *PrevDecl = LookupDecl(II, Decl::IDNS_Ordinary, S)) { 1417 if (S->isDeclScope(PrevDecl)) { 1418 Diag(D.getIdentifierLoc(), diag::err_param_redefinition, 1419 dyn_cast<NamedDecl>(PrevDecl)->getName()); 1420 1421 // Recover by removing the name 1422 II = 0; 1423 D.SetIdentifier(0, D.getIdentifierLoc()); 1424 } 1425 } 1426 1427 // Perform the default function/array conversion (C99 6.7.5.3p[7,8]). 1428 // Doing the promotion here has a win and a loss. The win is the type for 1429 // both Decl's and DeclRefExpr's will match (a convenient invariant for the 1430 // code generator). The loss is the orginal type isn't preserved. For example: 1431 // 1432 // void func(int parmvardecl[5]) { // convert "int [5]" to "int *" 1433 // int blockvardecl[5]; 1434 // sizeof(parmvardecl); // size == 4 1435 // sizeof(blockvardecl); // size == 20 1436 // } 1437 // 1438 // For expressions, all implicit conversions are captured using the 1439 // ImplicitCastExpr AST node (we have no such mechanism for Decl's). 1440 // 1441 // FIXME: If a source translation tool needs to see the original type, then 1442 // we need to consider storing both types (in ParmVarDecl)... 1443 // 1444 if (parmDeclType->isArrayType()) { 1445 // int x[restrict 4] -> int *restrict 1446 parmDeclType = Context.getArrayDecayedType(parmDeclType); 1447 } else if (parmDeclType->isFunctionType()) 1448 parmDeclType = Context.getPointerType(parmDeclType); 1449 1450 ParmVarDecl *New = ParmVarDecl::Create(Context, CurContext, 1451 D.getIdentifierLoc(), II, 1452 parmDeclType, VarDecl::None, 1453 0, 0); 1454 1455 if (D.getInvalidType()) 1456 New->setInvalidDecl(); 1457 1458 if (II) 1459 PushOnScopeChains(New, S); 1460 1461 HandleDeclAttributes(New, D.getDeclSpec().getAttributes(), 1462 D.getAttributes()); 1463 return New; 1464 1465} 1466 1467Sema::DeclTy *Sema::ActOnStartOfFunctionDef(Scope *FnBodyScope, Declarator &D) { 1468 assert(CurFunctionDecl == 0 && "Function parsing confused"); 1469 assert(D.getTypeObject(0).Kind == DeclaratorChunk::Function && 1470 "Not a function declarator!"); 1471 DeclaratorChunk::FunctionTypeInfo &FTI = D.getTypeObject(0).Fun; 1472 1473 // Verify 6.9.1p6: 'every identifier in the identifier list shall be declared' 1474 // for a K&R function. 1475 if (!FTI.hasPrototype) { 1476 for (unsigned i = 0, e = FTI.NumArgs; i != e; ++i) { 1477 if (FTI.ArgInfo[i].Param == 0) { 1478 Diag(FTI.ArgInfo[i].IdentLoc, diag::ext_param_not_declared, 1479 FTI.ArgInfo[i].Ident->getName()); 1480 // Implicitly declare the argument as type 'int' for lack of a better 1481 // type. 1482 DeclSpec DS; 1483 const char* PrevSpec; // unused 1484 DS.SetTypeSpecType(DeclSpec::TST_int, FTI.ArgInfo[i].IdentLoc, 1485 PrevSpec); 1486 Declarator ParamD(DS, Declarator::KNRTypeListContext); 1487 ParamD.SetIdentifier(FTI.ArgInfo[i].Ident, FTI.ArgInfo[i].IdentLoc); 1488 FTI.ArgInfo[i].Param = ActOnParamDeclarator(FnBodyScope, ParamD); 1489 } 1490 } 1491 1492 // Since this is a function definition, act as though we have information 1493 // about the arguments. 1494 if (FTI.NumArgs) 1495 FTI.hasPrototype = true; 1496 } else { 1497 // FIXME: Diagnose arguments without names in C. 1498 } 1499 1500 Scope *GlobalScope = FnBodyScope->getParent(); 1501 1502 // See if this is a redefinition. 1503 Decl *PrevDcl = LookupDecl(D.getIdentifier(), Decl::IDNS_Ordinary, 1504 GlobalScope); 1505 if (PrevDcl && IdResolver.isDeclInScope(PrevDcl, CurContext)) { 1506 if (FunctionDecl *FD = dyn_cast<FunctionDecl>(PrevDcl)) { 1507 const FunctionDecl *Definition; 1508 if (FD->getBody(Definition)) { 1509 Diag(D.getIdentifierLoc(), diag::err_redefinition, 1510 D.getIdentifier()->getName()); 1511 Diag(Definition->getLocation(), diag::err_previous_definition); 1512 } 1513 } 1514 } 1515 Decl *decl = static_cast<Decl*>(ActOnDeclarator(GlobalScope, D, 0)); 1516 FunctionDecl *FD = cast<FunctionDecl>(decl); 1517 CurFunctionDecl = FD; 1518 PushDeclContext(FD); 1519 1520 // Check the validity of our function parameters 1521 CheckParmsForFunctionDef(FD); 1522 1523 // Introduce our parameters into the function scope 1524 for (unsigned p = 0, NumParams = FD->getNumParams(); p < NumParams; ++p) { 1525 ParmVarDecl *Param = FD->getParamDecl(p); 1526 // If this has an identifier, add it to the scope stack. 1527 if (Param->getIdentifier()) 1528 PushOnScopeChains(Param, FnBodyScope); 1529 } 1530 1531 return FD; 1532} 1533 1534Sema::DeclTy *Sema::ActOnFinishFunctionBody(DeclTy *D, StmtTy *Body) { 1535 Decl *dcl = static_cast<Decl *>(D); 1536 if (FunctionDecl *FD = dyn_cast<FunctionDecl>(dcl)) { 1537 FD->setBody((Stmt*)Body); 1538 assert(FD == CurFunctionDecl && "Function parsing confused"); 1539 CurFunctionDecl = 0; 1540 } else if (ObjCMethodDecl *MD = dyn_cast<ObjCMethodDecl>(dcl)) { 1541 MD->setBody((Stmt*)Body); 1542 CurMethodDecl = 0; 1543 } 1544 PopDeclContext(); 1545 // Verify and clean out per-function state. 1546 1547 // Check goto/label use. 1548 for (llvm::DenseMap<IdentifierInfo*, LabelStmt*>::iterator 1549 I = LabelMap.begin(), E = LabelMap.end(); I != E; ++I) { 1550 // Verify that we have no forward references left. If so, there was a goto 1551 // or address of a label taken, but no definition of it. Label fwd 1552 // definitions are indicated with a null substmt. 1553 if (I->second->getSubStmt() == 0) { 1554 LabelStmt *L = I->second; 1555 // Emit error. 1556 Diag(L->getIdentLoc(), diag::err_undeclared_label_use, L->getName()); 1557 1558 // At this point, we have gotos that use the bogus label. Stitch it into 1559 // the function body so that they aren't leaked and that the AST is well 1560 // formed. 1561 if (Body) { 1562 L->setSubStmt(new NullStmt(L->getIdentLoc())); 1563 cast<CompoundStmt>((Stmt*)Body)->push_back(L); 1564 } else { 1565 // The whole function wasn't parsed correctly, just delete this. 1566 delete L; 1567 } 1568 } 1569 } 1570 LabelMap.clear(); 1571 1572 return D; 1573} 1574 1575/// ImplicitlyDefineFunction - An undeclared identifier was used in a function 1576/// call, forming a call to an implicitly defined function (per C99 6.5.1p2). 1577ScopedDecl *Sema::ImplicitlyDefineFunction(SourceLocation Loc, 1578 IdentifierInfo &II, Scope *S) { 1579 // Extension in C99. Legal in C90, but warn about it. 1580 if (getLangOptions().C99) 1581 Diag(Loc, diag::ext_implicit_function_decl, II.getName()); 1582 else 1583 Diag(Loc, diag::warn_implicit_function_decl, II.getName()); 1584 1585 // FIXME: handle stuff like: 1586 // void foo() { extern float X(); } 1587 // void bar() { X(); } <-- implicit decl for X in another scope. 1588 1589 // Set a Declarator for the implicit definition: int foo(); 1590 const char *Dummy; 1591 DeclSpec DS; 1592 bool Error = DS.SetTypeSpecType(DeclSpec::TST_int, Loc, Dummy); 1593 Error = Error; // Silence warning. 1594 assert(!Error && "Error setting up implicit decl!"); 1595 Declarator D(DS, Declarator::BlockContext); 1596 D.AddTypeInfo(DeclaratorChunk::getFunction(false, false, 0, 0, Loc)); 1597 D.SetIdentifier(&II, Loc); 1598 1599 // Insert this function into translation-unit scope. 1600 1601 DeclContext *PrevDC = CurContext; 1602 CurContext = Context.getTranslationUnitDecl(); 1603 1604 FunctionDecl *FD = 1605 dyn_cast<FunctionDecl>(static_cast<Decl*>(ActOnDeclarator(TUScope, D, 0))); 1606 FD->setImplicit(); 1607 1608 CurContext = PrevDC; 1609 1610 return FD; 1611} 1612 1613 1614TypedefDecl *Sema::ParseTypedefDecl(Scope *S, Declarator &D, QualType T, 1615 ScopedDecl *LastDeclarator) { 1616 assert(D.getIdentifier() && "Wrong callback for declspec without declarator"); 1617 assert(!T.isNull() && "GetTypeForDeclarator() returned null type"); 1618 1619 // Scope manipulation handled by caller. 1620 TypedefDecl *NewTD = TypedefDecl::Create(Context, CurContext, 1621 D.getIdentifierLoc(), 1622 D.getIdentifier(), 1623 T, LastDeclarator); 1624 if (D.getInvalidType()) 1625 NewTD->setInvalidDecl(); 1626 return NewTD; 1627} 1628 1629/// ActOnTag - This is invoked when we see 'struct foo' or 'struct {'. In the 1630/// former case, Name will be non-null. In the later case, Name will be null. 1631/// TagType indicates what kind of tag this is. TK indicates whether this is a 1632/// reference/declaration/definition of a tag. 1633Sema::DeclTy *Sema::ActOnTag(Scope *S, unsigned TagType, TagKind TK, 1634 SourceLocation KWLoc, IdentifierInfo *Name, 1635 SourceLocation NameLoc, AttributeList *Attr) { 1636 // If this is a use of an existing tag, it must have a name. 1637 assert((Name != 0 || TK == TK_Definition) && 1638 "Nameless record must be a definition!"); 1639 1640 Decl::Kind Kind; 1641 switch (TagType) { 1642 default: assert(0 && "Unknown tag type!"); 1643 case DeclSpec::TST_struct: Kind = Decl::Struct; break; 1644 case DeclSpec::TST_union: Kind = Decl::Union; break; 1645 case DeclSpec::TST_class: Kind = Decl::Class; break; 1646 case DeclSpec::TST_enum: Kind = Decl::Enum; break; 1647 } 1648 1649 // If this is a named struct, check to see if there was a previous forward 1650 // declaration or definition. 1651 // Use ScopedDecl instead of TagDecl, because a NamespaceDecl may come up. 1652 if (ScopedDecl *PrevDecl = 1653 dyn_cast_or_null<ScopedDecl>(LookupDecl(Name, Decl::IDNS_Tag, S))) { 1654 1655 assert((isa<TagDecl>(PrevDecl) || isa<NamespaceDecl>(PrevDecl)) && 1656 "unexpected Decl type"); 1657 if (TagDecl *PrevTagDecl = dyn_cast<TagDecl>(PrevDecl)) { 1658 // If this is a use of a previous tag, or if the tag is already declared in 1659 // the same scope (so that the definition/declaration completes or 1660 // rementions the tag), reuse the decl. 1661 if (TK == TK_Reference || 1662 IdResolver.isDeclInScope(PrevDecl, CurContext, S)) { 1663 // Make sure that this wasn't declared as an enum and now used as a struct 1664 // or something similar. 1665 if (PrevDecl->getKind() != Kind) { 1666 Diag(KWLoc, diag::err_use_with_wrong_tag, Name->getName()); 1667 Diag(PrevDecl->getLocation(), diag::err_previous_use); 1668 } 1669 1670 // If this is a use or a forward declaration, we're good. 1671 if (TK != TK_Definition) 1672 return PrevDecl; 1673 1674 // Diagnose attempts to redefine a tag. 1675 if (PrevTagDecl->isDefinition()) { 1676 Diag(NameLoc, diag::err_redefinition, Name->getName()); 1677 Diag(PrevDecl->getLocation(), diag::err_previous_definition); 1678 // If this is a redefinition, recover by making this struct be 1679 // anonymous, which will make any later references get the previous 1680 // definition. 1681 Name = 0; 1682 } else { 1683 // Okay, this is definition of a previously declared or referenced tag. 1684 // Move the location of the decl to be the definition site. 1685 PrevDecl->setLocation(NameLoc); 1686 return PrevDecl; 1687 } 1688 } 1689 // If we get here, this is a definition of a new struct type in a nested 1690 // scope, e.g. "struct foo; void bar() { struct foo; }", just create a new 1691 // type. 1692 } else { 1693 // The tag name clashes with a namespace name, issue an error and recover 1694 // by making this tag be anonymous. 1695 Diag(NameLoc, diag::err_redefinition_different_kind, Name->getName()); 1696 Diag(PrevDecl->getLocation(), diag::err_previous_definition); 1697 Name = 0; 1698 } 1699 } 1700 1701 // If there is an identifier, use the location of the identifier as the 1702 // location of the decl, otherwise use the location of the struct/union 1703 // keyword. 1704 SourceLocation Loc = NameLoc.isValid() ? NameLoc : KWLoc; 1705 1706 // Otherwise, if this is the first time we've seen this tag, create the decl. 1707 TagDecl *New; 1708 switch (Kind) { 1709 default: assert(0 && "Unknown tag kind!"); 1710 case Decl::Enum: 1711 // FIXME: Tag decls should be chained to any simultaneous vardecls, e.g.: 1712 // enum X { A, B, C } D; D should chain to X. 1713 New = EnumDecl::Create(Context, CurContext, Loc, Name, 0); 1714 // If this is an undefined enum, warn. 1715 if (TK != TK_Definition) Diag(Loc, diag::ext_forward_ref_enum); 1716 break; 1717 case Decl::Union: 1718 case Decl::Struct: 1719 case Decl::Class: 1720 // FIXME: Tag decls should be chained to any simultaneous vardecls, e.g.: 1721 // struct X { int A; } D; D should chain to X. 1722 New = RecordDecl::Create(Context, Kind, CurContext, Loc, Name, 0); 1723 break; 1724 } 1725 1726 // If this has an identifier, add it to the scope stack. 1727 if (Name) { 1728 // The scope passed in may not be a decl scope. Zip up the scope tree until 1729 // we find one that is. 1730 while ((S->getFlags() & Scope::DeclScope) == 0) 1731 S = S->getParent(); 1732 1733 // Add it to the decl chain. 1734 PushOnScopeChains(New, S); 1735 } 1736 1737 HandleDeclAttributes(New, Attr, 0); 1738 return New; 1739} 1740 1741static bool CalcFakeICEVal(const Expr* Expr, 1742 llvm::APSInt& Result, 1743 ASTContext& Context) { 1744 // Calculate the value of an expression that has a calculatable 1745 // value, but isn't an ICE. Currently, this only supports 1746 // a very narrow set of extensions, but it can be expanded if needed. 1747 if (const ParenExpr *PE = dyn_cast<ParenExpr>(Expr)) 1748 return CalcFakeICEVal(PE->getSubExpr(), Result, Context); 1749 1750 if (const CastExpr *CE = dyn_cast<CastExpr>(Expr)) { 1751 QualType CETy = CE->getType(); 1752 if ((CETy->isIntegralType() && !CETy->isBooleanType()) || 1753 CETy->isPointerType()) { 1754 if (CalcFakeICEVal(CE->getSubExpr(), Result, Context)) { 1755 Result.extOrTrunc(Context.getTypeSize(CETy)); 1756 // FIXME: This assumes pointers are signed. 1757 Result.setIsSigned(CETy->isSignedIntegerType() || 1758 CETy->isPointerType()); 1759 return true; 1760 } 1761 } 1762 } 1763 1764 if (Expr->getType()->isIntegralType()) 1765 return Expr->isIntegerConstantExpr(Result, Context); 1766 1767 return false; 1768} 1769 1770QualType Sema::TryFixInvalidVariablyModifiedType(QualType T) { 1771 // This method tries to turn a variable array into a constant 1772 // array even when the size isn't an ICE. This is necessary 1773 // for compatibility with code that depends on gcc's buggy 1774 // constant expression folding, like struct {char x[(int)(char*)2];} 1775 if (const VariableArrayType* VLATy = dyn_cast<VariableArrayType>(T)) { 1776 llvm::APSInt Result(32); 1777 if (VLATy->getSizeExpr() && 1778 CalcFakeICEVal(VLATy->getSizeExpr(), Result, Context) && 1779 Result > llvm::APSInt(Result.getBitWidth(), Result.isUnsigned())) { 1780 return Context.getConstantArrayType(VLATy->getElementType(), 1781 Result, ArrayType::Normal, 0); 1782 } 1783 } 1784 return QualType(); 1785} 1786 1787/// ActOnField - Each field of a struct/union/class is passed into this in order 1788/// to create a FieldDecl object for it. 1789Sema::DeclTy *Sema::ActOnField(Scope *S, 1790 SourceLocation DeclStart, 1791 Declarator &D, ExprTy *BitfieldWidth) { 1792 IdentifierInfo *II = D.getIdentifier(); 1793 Expr *BitWidth = (Expr*)BitfieldWidth; 1794 SourceLocation Loc = DeclStart; 1795 if (II) Loc = D.getIdentifierLoc(); 1796 1797 // FIXME: Unnamed fields can be handled in various different ways, for 1798 // example, unnamed unions inject all members into the struct namespace! 1799 1800 1801 if (BitWidth) { 1802 // TODO: Validate. 1803 //printf("WARNING: BITFIELDS IGNORED!\n"); 1804 1805 // 6.7.2.1p3 1806 // 6.7.2.1p4 1807 1808 } else { 1809 // Not a bitfield. 1810 1811 // validate II. 1812 1813 } 1814 1815 QualType T = GetTypeForDeclarator(D, S); 1816 assert(!T.isNull() && "GetTypeForDeclarator() returned null type"); 1817 bool InvalidDecl = false; 1818 1819 // C99 6.7.2.1p8: A member of a structure or union may have any type other 1820 // than a variably modified type. 1821 if (T->isVariablyModifiedType()) { 1822 QualType FixedTy = TryFixInvalidVariablyModifiedType(T); 1823 if (!FixedTy.isNull()) { 1824 Diag(Loc, diag::warn_illegal_constant_array_size, Loc); 1825 T = FixedTy; 1826 } else { 1827 // FIXME: This diagnostic needs work 1828 Diag(Loc, diag::err_typecheck_illegal_vla, Loc); 1829 InvalidDecl = true; 1830 } 1831 } 1832 // FIXME: Chain fielddecls together. 1833 FieldDecl *NewFD = FieldDecl::Create(Context, Loc, II, T, BitWidth); 1834 1835 HandleDeclAttributes(NewFD, D.getDeclSpec().getAttributes(), 1836 D.getAttributes()); 1837 1838 if (D.getInvalidType() || InvalidDecl) 1839 NewFD->setInvalidDecl(); 1840 return NewFD; 1841} 1842 1843/// TranslateIvarVisibility - Translate visibility from a token ID to an 1844/// AST enum value. 1845static ObjCIvarDecl::AccessControl 1846TranslateIvarVisibility(tok::ObjCKeywordKind ivarVisibility) { 1847 switch (ivarVisibility) { 1848 case tok::objc_private: return ObjCIvarDecl::Private; 1849 case tok::objc_public: return ObjCIvarDecl::Public; 1850 case tok::objc_protected: return ObjCIvarDecl::Protected; 1851 case tok::objc_package: return ObjCIvarDecl::Package; 1852 default: assert(false && "Unknown visitibility kind"); 1853 } 1854} 1855 1856/// ActOnIvar - Each ivar field of an objective-c class is passed into this 1857/// in order to create an IvarDecl object for it. 1858Sema::DeclTy *Sema::ActOnIvar(Scope *S, 1859 SourceLocation DeclStart, 1860 Declarator &D, ExprTy *BitfieldWidth, 1861 tok::ObjCKeywordKind Visibility) { 1862 IdentifierInfo *II = D.getIdentifier(); 1863 Expr *BitWidth = (Expr*)BitfieldWidth; 1864 SourceLocation Loc = DeclStart; 1865 if (II) Loc = D.getIdentifierLoc(); 1866 1867 // FIXME: Unnamed fields can be handled in various different ways, for 1868 // example, unnamed unions inject all members into the struct namespace! 1869 1870 1871 if (BitWidth) { 1872 // TODO: Validate. 1873 //printf("WARNING: BITFIELDS IGNORED!\n"); 1874 1875 // 6.7.2.1p3 1876 // 6.7.2.1p4 1877 1878 } else { 1879 // Not a bitfield. 1880 1881 // validate II. 1882 1883 } 1884 1885 QualType T = GetTypeForDeclarator(D, S); 1886 assert(!T.isNull() && "GetTypeForDeclarator() returned null type"); 1887 bool InvalidDecl = false; 1888 1889 // C99 6.7.2.1p8: A member of a structure or union may have any type other 1890 // than a variably modified type. 1891 if (T->isVariablyModifiedType()) { 1892 // FIXME: This diagnostic needs work 1893 Diag(Loc, diag::err_typecheck_illegal_vla, Loc); 1894 InvalidDecl = true; 1895 } 1896 1897 ObjCIvarDecl *NewID = ObjCIvarDecl::Create(Context, Loc, II, T); 1898 1899 HandleDeclAttributes(NewID, D.getDeclSpec().getAttributes(), 1900 D.getAttributes()); 1901 1902 if (D.getInvalidType() || InvalidDecl) 1903 NewID->setInvalidDecl(); 1904 // If we have visibility info, make sure the AST is set accordingly. 1905 if (Visibility != tok::objc_not_keyword) 1906 NewID->setAccessControl(TranslateIvarVisibility(Visibility)); 1907 return NewID; 1908} 1909 1910void Sema::ActOnFields(Scope* S, 1911 SourceLocation RecLoc, DeclTy *RecDecl, 1912 DeclTy **Fields, unsigned NumFields, 1913 SourceLocation LBrac, SourceLocation RBrac) { 1914 Decl *EnclosingDecl = static_cast<Decl*>(RecDecl); 1915 assert(EnclosingDecl && "missing record or interface decl"); 1916 RecordDecl *Record = dyn_cast<RecordDecl>(EnclosingDecl); 1917 1918 if (Record && Record->isDefinition()) { 1919 // Diagnose code like: 1920 // struct S { struct S {} X; }; 1921 // We discover this when we complete the outer S. Reject and ignore the 1922 // outer S. 1923 Diag(Record->getLocation(), diag::err_nested_redefinition, 1924 Record->getKindName()); 1925 Diag(RecLoc, diag::err_previous_definition); 1926 Record->setInvalidDecl(); 1927 return; 1928 } 1929 // Verify that all the fields are okay. 1930 unsigned NumNamedMembers = 0; 1931 llvm::SmallVector<FieldDecl*, 32> RecFields; 1932 llvm::SmallSet<const IdentifierInfo*, 32> FieldIDs; 1933 1934 for (unsigned i = 0; i != NumFields; ++i) { 1935 1936 FieldDecl *FD = cast_or_null<FieldDecl>(static_cast<Decl*>(Fields[i])); 1937 assert(FD && "missing field decl"); 1938 1939 // Remember all fields. 1940 RecFields.push_back(FD); 1941 1942 // Get the type for the field. 1943 Type *FDTy = FD->getType().getTypePtr(); 1944 1945 // C99 6.7.2.1p2 - A field may not be a function type. 1946 if (FDTy->isFunctionType()) { 1947 Diag(FD->getLocation(), diag::err_field_declared_as_function, 1948 FD->getName()); 1949 FD->setInvalidDecl(); 1950 EnclosingDecl->setInvalidDecl(); 1951 continue; 1952 } 1953 // C99 6.7.2.1p2 - A field may not be an incomplete type except... 1954 if (FDTy->isIncompleteType()) { 1955 if (!Record) { // Incomplete ivar type is always an error. 1956 Diag(FD->getLocation(), diag::err_field_incomplete, FD->getName()); 1957 FD->setInvalidDecl(); 1958 EnclosingDecl->setInvalidDecl(); 1959 continue; 1960 } 1961 if (i != NumFields-1 || // ... that the last member ... 1962 Record->getKind() != Decl::Struct || // ... of a structure ... 1963 !FDTy->isArrayType()) { //... may have incomplete array type. 1964 Diag(FD->getLocation(), diag::err_field_incomplete, FD->getName()); 1965 FD->setInvalidDecl(); 1966 EnclosingDecl->setInvalidDecl(); 1967 continue; 1968 } 1969 if (NumNamedMembers < 1) { //... must have more than named member ... 1970 Diag(FD->getLocation(), diag::err_flexible_array_empty_struct, 1971 FD->getName()); 1972 FD->setInvalidDecl(); 1973 EnclosingDecl->setInvalidDecl(); 1974 continue; 1975 } 1976 // Okay, we have a legal flexible array member at the end of the struct. 1977 if (Record) 1978 Record->setHasFlexibleArrayMember(true); 1979 } 1980 /// C99 6.7.2.1p2 - a struct ending in a flexible array member cannot be the 1981 /// field of another structure or the element of an array. 1982 if (const RecordType *FDTTy = FDTy->getAsRecordType()) { 1983 if (FDTTy->getDecl()->hasFlexibleArrayMember()) { 1984 // If this is a member of a union, then entire union becomes "flexible". 1985 if (Record && Record->getKind() == Decl::Union) { 1986 Record->setHasFlexibleArrayMember(true); 1987 } else { 1988 // If this is a struct/class and this is not the last element, reject 1989 // it. Note that GCC supports variable sized arrays in the middle of 1990 // structures. 1991 if (i != NumFields-1) { 1992 Diag(FD->getLocation(), diag::err_variable_sized_type_in_struct, 1993 FD->getName()); 1994 FD->setInvalidDecl(); 1995 EnclosingDecl->setInvalidDecl(); 1996 continue; 1997 } 1998 // We support flexible arrays at the end of structs in other structs 1999 // as an extension. 2000 Diag(FD->getLocation(), diag::ext_flexible_array_in_struct, 2001 FD->getName()); 2002 if (Record) 2003 Record->setHasFlexibleArrayMember(true); 2004 } 2005 } 2006 } 2007 /// A field cannot be an Objective-c object 2008 if (FDTy->isObjCInterfaceType()) { 2009 Diag(FD->getLocation(), diag::err_statically_allocated_object, 2010 FD->getName()); 2011 FD->setInvalidDecl(); 2012 EnclosingDecl->setInvalidDecl(); 2013 continue; 2014 } 2015 // Keep track of the number of named members. 2016 if (IdentifierInfo *II = FD->getIdentifier()) { 2017 // Detect duplicate member names. 2018 if (!FieldIDs.insert(II)) { 2019 Diag(FD->getLocation(), diag::err_duplicate_member, II->getName()); 2020 // Find the previous decl. 2021 SourceLocation PrevLoc; 2022 for (unsigned i = 0, e = RecFields.size(); ; ++i) { 2023 assert(i != e && "Didn't find previous def!"); 2024 if (RecFields[i]->getIdentifier() == II) { 2025 PrevLoc = RecFields[i]->getLocation(); 2026 break; 2027 } 2028 } 2029 Diag(PrevLoc, diag::err_previous_definition); 2030 FD->setInvalidDecl(); 2031 EnclosingDecl->setInvalidDecl(); 2032 continue; 2033 } 2034 ++NumNamedMembers; 2035 } 2036 } 2037 2038 // Okay, we successfully defined 'Record'. 2039 if (Record) { 2040 Record->defineBody(&RecFields[0], RecFields.size()); 2041 Consumer.HandleTagDeclDefinition(Record); 2042 } else { 2043 ObjCIvarDecl **ClsFields = reinterpret_cast<ObjCIvarDecl**>(&RecFields[0]); 2044 if (ObjCInterfaceDecl *ID = dyn_cast<ObjCInterfaceDecl>(EnclosingDecl)) 2045 ID->addInstanceVariablesToClass(ClsFields, RecFields.size(), RBrac); 2046 else if (ObjCImplementationDecl *IMPDecl = 2047 dyn_cast<ObjCImplementationDecl>(EnclosingDecl)) { 2048 assert(IMPDecl && "ActOnFields - missing ObjCImplementationDecl"); 2049 IMPDecl->ObjCAddInstanceVariablesToClassImpl(ClsFields, RecFields.size()); 2050 CheckImplementationIvars(IMPDecl, ClsFields, RecFields.size(), RBrac); 2051 } 2052 } 2053} 2054 2055Sema::DeclTy *Sema::ActOnEnumConstant(Scope *S, DeclTy *theEnumDecl, 2056 DeclTy *lastEnumConst, 2057 SourceLocation IdLoc, IdentifierInfo *Id, 2058 SourceLocation EqualLoc, ExprTy *val) { 2059 EnumDecl *TheEnumDecl = cast<EnumDecl>(static_cast<Decl*>(theEnumDecl)); 2060 EnumConstantDecl *LastEnumConst = 2061 cast_or_null<EnumConstantDecl>(static_cast<Decl*>(lastEnumConst)); 2062 Expr *Val = static_cast<Expr*>(val); 2063 2064 // The scope passed in may not be a decl scope. Zip up the scope tree until 2065 // we find one that is. 2066 while ((S->getFlags() & Scope::DeclScope) == 0) 2067 S = S->getParent(); 2068 2069 // Verify that there isn't already something declared with this name in this 2070 // scope. 2071 if (Decl *PrevDecl = LookupDecl(Id, Decl::IDNS_Ordinary, S)) { 2072 if (IdResolver.isDeclInScope(PrevDecl, CurContext, S)) { 2073 if (isa<EnumConstantDecl>(PrevDecl)) 2074 Diag(IdLoc, diag::err_redefinition_of_enumerator, Id->getName()); 2075 else 2076 Diag(IdLoc, diag::err_redefinition, Id->getName()); 2077 Diag(PrevDecl->getLocation(), diag::err_previous_definition); 2078 delete Val; 2079 return 0; 2080 } 2081 } 2082 2083 llvm::APSInt EnumVal(32); 2084 QualType EltTy; 2085 if (Val) { 2086 // Make sure to promote the operand type to int. 2087 UsualUnaryConversions(Val); 2088 2089 // C99 6.7.2.2p2: Make sure we have an integer constant expression. 2090 SourceLocation ExpLoc; 2091 if (!Val->isIntegerConstantExpr(EnumVal, Context, &ExpLoc)) { 2092 Diag(ExpLoc, diag::err_enum_value_not_integer_constant_expr, 2093 Id->getName()); 2094 delete Val; 2095 Val = 0; // Just forget about it. 2096 } else { 2097 EltTy = Val->getType(); 2098 } 2099 } 2100 2101 if (!Val) { 2102 if (LastEnumConst) { 2103 // Assign the last value + 1. 2104 EnumVal = LastEnumConst->getInitVal(); 2105 ++EnumVal; 2106 2107 // Check for overflow on increment. 2108 if (EnumVal < LastEnumConst->getInitVal()) 2109 Diag(IdLoc, diag::warn_enum_value_overflow); 2110 2111 EltTy = LastEnumConst->getType(); 2112 } else { 2113 // First value, set to zero. 2114 EltTy = Context.IntTy; 2115 EnumVal.zextOrTrunc(static_cast<uint32_t>(Context.getTypeSize(EltTy))); 2116 } 2117 } 2118 2119 EnumConstantDecl *New = 2120 EnumConstantDecl::Create(Context, TheEnumDecl, IdLoc, Id, EltTy, 2121 Val, EnumVal, 2122 LastEnumConst); 2123 2124 // Register this decl in the current scope stack. 2125 PushOnScopeChains(New, S); 2126 return New; 2127} 2128 2129void Sema::ActOnEnumBody(SourceLocation EnumLoc, DeclTy *EnumDeclX, 2130 DeclTy **Elements, unsigned NumElements) { 2131 EnumDecl *Enum = cast<EnumDecl>(static_cast<Decl*>(EnumDeclX)); 2132 assert(!Enum->isDefinition() && "Enum redefinitions can't reach here"); 2133 2134 // TODO: If the result value doesn't fit in an int, it must be a long or long 2135 // long value. ISO C does not support this, but GCC does as an extension, 2136 // emit a warning. 2137 unsigned IntWidth = Context.Target.getIntWidth(); 2138 2139 // Verify that all the values are okay, compute the size of the values, and 2140 // reverse the list. 2141 unsigned NumNegativeBits = 0; 2142 unsigned NumPositiveBits = 0; 2143 2144 // Keep track of whether all elements have type int. 2145 bool AllElementsInt = true; 2146 2147 EnumConstantDecl *EltList = 0; 2148 for (unsigned i = 0; i != NumElements; ++i) { 2149 EnumConstantDecl *ECD = 2150 cast_or_null<EnumConstantDecl>(static_cast<Decl*>(Elements[i])); 2151 if (!ECD) continue; // Already issued a diagnostic. 2152 2153 // If the enum value doesn't fit in an int, emit an extension warning. 2154 const llvm::APSInt &InitVal = ECD->getInitVal(); 2155 assert(InitVal.getBitWidth() >= IntWidth && 2156 "Should have promoted value to int"); 2157 if (InitVal.getBitWidth() > IntWidth) { 2158 llvm::APSInt V(InitVal); 2159 V.trunc(IntWidth); 2160 V.extend(InitVal.getBitWidth()); 2161 if (V != InitVal) 2162 Diag(ECD->getLocation(), diag::ext_enum_value_not_int, 2163 InitVal.toString()); 2164 } 2165 2166 // Keep track of the size of positive and negative values. 2167 if (InitVal.isUnsigned() || InitVal.isNonNegative()) 2168 NumPositiveBits = std::max(NumPositiveBits, 2169 (unsigned)InitVal.getActiveBits()); 2170 else 2171 NumNegativeBits = std::max(NumNegativeBits, 2172 (unsigned)InitVal.getMinSignedBits()); 2173 2174 // Keep track of whether every enum element has type int (very commmon). 2175 if (AllElementsInt) 2176 AllElementsInt = ECD->getType() == Context.IntTy; 2177 2178 ECD->setNextDeclarator(EltList); 2179 EltList = ECD; 2180 } 2181 2182 // Figure out the type that should be used for this enum. 2183 // FIXME: Support attribute(packed) on enums and -fshort-enums. 2184 QualType BestType; 2185 unsigned BestWidth; 2186 2187 if (NumNegativeBits) { 2188 // If there is a negative value, figure out the smallest integer type (of 2189 // int/long/longlong) that fits. 2190 if (NumNegativeBits <= IntWidth && NumPositiveBits < IntWidth) { 2191 BestType = Context.IntTy; 2192 BestWidth = IntWidth; 2193 } else { 2194 BestWidth = Context.Target.getLongWidth(); 2195 2196 if (NumNegativeBits <= BestWidth && NumPositiveBits < BestWidth) 2197 BestType = Context.LongTy; 2198 else { 2199 BestWidth = Context.Target.getLongLongWidth(); 2200 2201 if (NumNegativeBits > BestWidth || NumPositiveBits >= BestWidth) 2202 Diag(Enum->getLocation(), diag::warn_enum_too_large); 2203 BestType = Context.LongLongTy; 2204 } 2205 } 2206 } else { 2207 // If there is no negative value, figure out which of uint, ulong, ulonglong 2208 // fits. 2209 if (NumPositiveBits <= IntWidth) { 2210 BestType = Context.UnsignedIntTy; 2211 BestWidth = IntWidth; 2212 } else if (NumPositiveBits <= 2213 (BestWidth = Context.Target.getLongWidth())) { 2214 BestType = Context.UnsignedLongTy; 2215 } else { 2216 BestWidth = Context.Target.getLongLongWidth(); 2217 assert(NumPositiveBits <= BestWidth && 2218 "How could an initializer get larger than ULL?"); 2219 BestType = Context.UnsignedLongLongTy; 2220 } 2221 } 2222 2223 // Loop over all of the enumerator constants, changing their types to match 2224 // the type of the enum if needed. 2225 for (unsigned i = 0; i != NumElements; ++i) { 2226 EnumConstantDecl *ECD = 2227 cast_or_null<EnumConstantDecl>(static_cast<Decl*>(Elements[i])); 2228 if (!ECD) continue; // Already issued a diagnostic. 2229 2230 // Standard C says the enumerators have int type, but we allow, as an 2231 // extension, the enumerators to be larger than int size. If each 2232 // enumerator value fits in an int, type it as an int, otherwise type it the 2233 // same as the enumerator decl itself. This means that in "enum { X = 1U }" 2234 // that X has type 'int', not 'unsigned'. 2235 if (ECD->getType() == Context.IntTy) { 2236 // Make sure the init value is signed. 2237 llvm::APSInt IV = ECD->getInitVal(); 2238 IV.setIsSigned(true); 2239 ECD->setInitVal(IV); 2240 continue; // Already int type. 2241 } 2242 2243 // Determine whether the value fits into an int. 2244 llvm::APSInt InitVal = ECD->getInitVal(); 2245 bool FitsInInt; 2246 if (InitVal.isUnsigned() || !InitVal.isNegative()) 2247 FitsInInt = InitVal.getActiveBits() < IntWidth; 2248 else 2249 FitsInInt = InitVal.getMinSignedBits() <= IntWidth; 2250 2251 // If it fits into an integer type, force it. Otherwise force it to match 2252 // the enum decl type. 2253 QualType NewTy; 2254 unsigned NewWidth; 2255 bool NewSign; 2256 if (FitsInInt) { 2257 NewTy = Context.IntTy; 2258 NewWidth = IntWidth; 2259 NewSign = true; 2260 } else if (ECD->getType() == BestType) { 2261 // Already the right type! 2262 continue; 2263 } else { 2264 NewTy = BestType; 2265 NewWidth = BestWidth; 2266 NewSign = BestType->isSignedIntegerType(); 2267 } 2268 2269 // Adjust the APSInt value. 2270 InitVal.extOrTrunc(NewWidth); 2271 InitVal.setIsSigned(NewSign); 2272 ECD->setInitVal(InitVal); 2273 2274 // Adjust the Expr initializer and type. 2275 ECD->setInitExpr(new ImplicitCastExpr(NewTy, ECD->getInitExpr())); 2276 ECD->setType(NewTy); 2277 } 2278 2279 Enum->defineElements(EltList, BestType); 2280 Consumer.HandleTagDeclDefinition(Enum); 2281} 2282 2283Sema::DeclTy *Sema::ActOnFileScopeAsmDecl(SourceLocation Loc, 2284 ExprTy *expr) { 2285 StringLiteral *AsmString = cast<StringLiteral>((Expr*)expr); 2286 2287 return FileScopeAsmDecl::Create(Context, Loc, AsmString); 2288} 2289 2290Sema::DeclTy* Sema::ActOnLinkageSpec(SourceLocation Loc, 2291 SourceLocation LBrace, 2292 SourceLocation RBrace, 2293 const char *Lang, 2294 unsigned StrSize, 2295 DeclTy *D) { 2296 LinkageSpecDecl::LanguageIDs Language; 2297 Decl *dcl = static_cast<Decl *>(D); 2298 if (strncmp(Lang, "\"C\"", StrSize) == 0) 2299 Language = LinkageSpecDecl::lang_c; 2300 else if (strncmp(Lang, "\"C++\"", StrSize) == 0) 2301 Language = LinkageSpecDecl::lang_cxx; 2302 else { 2303 Diag(Loc, diag::err_bad_language); 2304 return 0; 2305 } 2306 2307 // FIXME: Add all the various semantics of linkage specifications 2308 return LinkageSpecDecl::Create(Context, Loc, Language, dcl); 2309} 2310 2311void Sema::HandleDeclAttribute(Decl *New, AttributeList *Attr) { 2312 2313 switch (Attr->getKind()) { 2314 case AttributeList::AT_vector_size: 2315 if (ValueDecl *vDecl = dyn_cast<ValueDecl>(New)) { 2316 QualType newType = HandleVectorTypeAttribute(vDecl->getType(), Attr); 2317 if (!newType.isNull()) // install the new vector type into the decl 2318 vDecl->setType(newType); 2319 } 2320 if (TypedefDecl *tDecl = dyn_cast<TypedefDecl>(New)) { 2321 QualType newType = HandleVectorTypeAttribute(tDecl->getUnderlyingType(), 2322 Attr); 2323 if (!newType.isNull()) // install the new vector type into the decl 2324 tDecl->setUnderlyingType(newType); 2325 } 2326 break; 2327 case AttributeList::AT_ext_vector_type: 2328 if (TypedefDecl *tDecl = dyn_cast<TypedefDecl>(New)) 2329 HandleExtVectorTypeAttribute(tDecl, Attr); 2330 else 2331 Diag(Attr->getLoc(), 2332 diag::err_typecheck_ext_vector_not_typedef); 2333 break; 2334 case AttributeList::AT_address_space: 2335 if (TypedefDecl *tDecl = dyn_cast<TypedefDecl>(New)) { 2336 QualType newType = HandleAddressSpaceTypeAttribute( 2337 tDecl->getUnderlyingType(), 2338 Attr); 2339 tDecl->setUnderlyingType(newType); 2340 } else if (ValueDecl *vDecl = dyn_cast<ValueDecl>(New)) { 2341 QualType newType = HandleAddressSpaceTypeAttribute(vDecl->getType(), 2342 Attr); 2343 // install the new addr spaced type into the decl 2344 vDecl->setType(newType); 2345 } 2346 break; 2347 case AttributeList::AT_mode: 2348 if (TypedefDecl *tDecl = dyn_cast<TypedefDecl>(New)) { 2349 QualType newType = HandleModeTypeAttribute(tDecl->getUnderlyingType(), 2350 Attr); 2351 tDecl->setUnderlyingType(newType); 2352 } else if (ValueDecl *vDecl = dyn_cast<ValueDecl>(New)) { 2353 QualType newType = HandleModeTypeAttribute(vDecl->getType(), Attr); 2354 vDecl->setType(newType); 2355 } 2356 // FIXME: Diagnostic? 2357 break; 2358 case AttributeList::AT_alias: 2359 HandleAliasAttribute(New, Attr); 2360 break; 2361 case AttributeList::AT_deprecated: 2362 HandleDeprecatedAttribute(New, Attr); 2363 break; 2364 case AttributeList::AT_visibility: 2365 HandleVisibilityAttribute(New, Attr); 2366 break; 2367 case AttributeList::AT_weak: 2368 HandleWeakAttribute(New, Attr); 2369 break; 2370 case AttributeList::AT_dllimport: 2371 HandleDLLImportAttribute(New, Attr); 2372 break; 2373 case AttributeList::AT_dllexport: 2374 HandleDLLExportAttribute(New, Attr); 2375 break; 2376 case AttributeList::AT_nothrow: 2377 HandleNothrowAttribute(New, Attr); 2378 break; 2379 case AttributeList::AT_stdcall: 2380 HandleStdCallAttribute(New, Attr); 2381 break; 2382 case AttributeList::AT_fastcall: 2383 HandleFastCallAttribute(New, Attr); 2384 break; 2385 case AttributeList::AT_aligned: 2386 HandleAlignedAttribute(New, Attr); 2387 break; 2388 case AttributeList::AT_packed: 2389 HandlePackedAttribute(New, Attr); 2390 break; 2391 case AttributeList::AT_annotate: 2392 HandleAnnotateAttribute(New, Attr); 2393 break; 2394 case AttributeList::AT_noreturn: 2395 HandleNoReturnAttribute(New, Attr); 2396 break; 2397 case AttributeList::AT_format: 2398 HandleFormatAttribute(New, Attr); 2399 break; 2400 case AttributeList::AT_transparent_union: 2401 HandleTransparentUnionAttribute(New, Attr); 2402 break; 2403 default: 2404#if 0 2405 // TODO: when we have the full set of attributes, warn about unknown ones. 2406 Diag(Attr->getLoc(), diag::warn_attribute_ignored, 2407 Attr->getName()->getName()); 2408#endif 2409 break; 2410 } 2411} 2412 2413void Sema::HandleDeclAttributes(Decl *New, AttributeList *declspec_prefix, 2414 AttributeList *declarator_postfix) { 2415 while (declspec_prefix) { 2416 HandleDeclAttribute(New, declspec_prefix); 2417 declspec_prefix = declspec_prefix->getNext(); 2418 } 2419 while (declarator_postfix) { 2420 HandleDeclAttribute(New, declarator_postfix); 2421 declarator_postfix = declarator_postfix->getNext(); 2422 } 2423} 2424 2425void Sema::HandleExtVectorTypeAttribute(TypedefDecl *tDecl, 2426 AttributeList *rawAttr) { 2427 QualType curType = tDecl->getUnderlyingType(); 2428 // check the attribute arguments. 2429 if (rawAttr->getNumArgs() != 1) { 2430 Diag(rawAttr->getLoc(), diag::err_attribute_wrong_number_arguments, 2431 std::string("1")); 2432 return; 2433 } 2434 Expr *sizeExpr = static_cast<Expr *>(rawAttr->getArg(0)); 2435 llvm::APSInt vecSize(32); 2436 if (!sizeExpr->isIntegerConstantExpr(vecSize, Context)) { 2437 Diag(rawAttr->getLoc(), diag::err_attribute_argument_not_int, 2438 "ext_vector_type", sizeExpr->getSourceRange()); 2439 return; 2440 } 2441 // unlike gcc's vector_size attribute, we do not allow vectors to be defined 2442 // in conjunction with complex types (pointers, arrays, functions, etc.). 2443 Type *canonType = curType.getCanonicalType().getTypePtr(); 2444 if (!(canonType->isIntegerType() || canonType->isRealFloatingType())) { 2445 Diag(rawAttr->getLoc(), diag::err_attribute_invalid_vector_type, 2446 curType.getCanonicalType().getAsString()); 2447 return; 2448 } 2449 // unlike gcc's vector_size attribute, the size is specified as the 2450 // number of elements, not the number of bytes. 2451 unsigned vectorSize = static_cast<unsigned>(vecSize.getZExtValue()); 2452 2453 if (vectorSize == 0) { 2454 Diag(rawAttr->getLoc(), diag::err_attribute_zero_size, 2455 sizeExpr->getSourceRange()); 2456 return; 2457 } 2458 // Instantiate/Install the vector type, the number of elements is > 0. 2459 tDecl->setUnderlyingType(Context.getExtVectorType(curType, vectorSize)); 2460 // Remember this typedef decl, we will need it later for diagnostics. 2461 ExtVectorDecls.push_back(tDecl); 2462} 2463 2464QualType Sema::HandleVectorTypeAttribute(QualType curType, 2465 AttributeList *rawAttr) { 2466 // check the attribute arugments. 2467 if (rawAttr->getNumArgs() != 1) { 2468 Diag(rawAttr->getLoc(), diag::err_attribute_wrong_number_arguments, 2469 std::string("1")); 2470 return QualType(); 2471 } 2472 Expr *sizeExpr = static_cast<Expr *>(rawAttr->getArg(0)); 2473 llvm::APSInt vecSize(32); 2474 if (!sizeExpr->isIntegerConstantExpr(vecSize, Context)) { 2475 Diag(rawAttr->getLoc(), diag::err_attribute_argument_not_int, 2476 "vector_size", sizeExpr->getSourceRange()); 2477 return QualType(); 2478 } 2479 // navigate to the base type - we need to provide for vector pointers, 2480 // vector arrays, and functions returning vectors. 2481 Type *canonType = curType.getCanonicalType().getTypePtr(); 2482 2483 if (canonType->isPointerType() || canonType->isArrayType() || 2484 canonType->isFunctionType()) { 2485 assert(0 && "HandleVector(): Complex type construction unimplemented"); 2486 /* FIXME: rebuild the type from the inside out, vectorizing the inner type. 2487 do { 2488 if (PointerType *PT = dyn_cast<PointerType>(canonType)) 2489 canonType = PT->getPointeeType().getTypePtr(); 2490 else if (ArrayType *AT = dyn_cast<ArrayType>(canonType)) 2491 canonType = AT->getElementType().getTypePtr(); 2492 else if (FunctionType *FT = dyn_cast<FunctionType>(canonType)) 2493 canonType = FT->getResultType().getTypePtr(); 2494 } while (canonType->isPointerType() || canonType->isArrayType() || 2495 canonType->isFunctionType()); 2496 */ 2497 } 2498 // the base type must be integer or float. 2499 if (!(canonType->isIntegerType() || canonType->isRealFloatingType())) { 2500 Diag(rawAttr->getLoc(), diag::err_attribute_invalid_vector_type, 2501 curType.getCanonicalType().getAsString()); 2502 return QualType(); 2503 } 2504 unsigned typeSize = static_cast<unsigned>(Context.getTypeSize(curType)); 2505 // vecSize is specified in bytes - convert to bits. 2506 unsigned vectorSize = static_cast<unsigned>(vecSize.getZExtValue() * 8); 2507 2508 // the vector size needs to be an integral multiple of the type size. 2509 if (vectorSize % typeSize) { 2510 Diag(rawAttr->getLoc(), diag::err_attribute_invalid_size, 2511 sizeExpr->getSourceRange()); 2512 return QualType(); 2513 } 2514 if (vectorSize == 0) { 2515 Diag(rawAttr->getLoc(), diag::err_attribute_zero_size, 2516 sizeExpr->getSourceRange()); 2517 return QualType(); 2518 } 2519 // Instantiate the vector type, the number of elements is > 0, and not 2520 // required to be a power of 2, unlike GCC. 2521 return Context.getVectorType(curType, vectorSize/typeSize); 2522} 2523 2524void Sema::HandlePackedAttribute(Decl *d, AttributeList *rawAttr) { 2525 // check the attribute arguments. 2526 if (rawAttr->getNumArgs() > 0) { 2527 Diag(rawAttr->getLoc(), diag::err_attribute_wrong_number_arguments, 2528 std::string("0")); 2529 return; 2530 } 2531 2532 if (TagDecl *TD = dyn_cast<TagDecl>(d)) 2533 TD->addAttr(new PackedAttr); 2534 else if (FieldDecl *FD = dyn_cast<FieldDecl>(d)) { 2535 // If the alignment is less than or equal to 8 bits, the packed attribute 2536 // has no effect. 2537 if (!FD->getType()->isIncompleteType() && 2538 Context.getTypeAlign(FD->getType()) <= 8) 2539 Diag(rawAttr->getLoc(), 2540 diag::warn_attribute_ignored_for_field_of_type, 2541 rawAttr->getName()->getName(), FD->getType().getAsString()); 2542 else 2543 FD->addAttr(new PackedAttr); 2544 } else 2545 Diag(rawAttr->getLoc(), diag::warn_attribute_ignored, 2546 rawAttr->getName()->getName()); 2547} 2548 2549void Sema::HandleAliasAttribute(Decl *d, AttributeList *rawAttr) { 2550 // check the attribute arguments. 2551 if (rawAttr->getNumArgs() != 1) { 2552 Diag(rawAttr->getLoc(), diag::err_attribute_wrong_number_arguments, 2553 std::string("1")); 2554 return; 2555 } 2556 2557 Expr *Arg = static_cast<Expr*>(rawAttr->getArg(0)); 2558 Arg = Arg->IgnoreParenCasts(); 2559 StringLiteral *Str = dyn_cast<StringLiteral>(Arg); 2560 2561 if (Str == 0 || Str->isWide()) { 2562 Diag(rawAttr->getLoc(), diag::err_attribute_argument_n_not_string, 2563 "alias", std::string("1")); 2564 return; 2565 } 2566 2567 const char *Alias = Str->getStrData(); 2568 unsigned AliasLen = Str->getByteLength(); 2569 2570 // FIXME: check if target symbol exists in current file 2571 2572 d->addAttr(new AliasAttr(std::string(Alias, AliasLen))); 2573} 2574 2575void Sema::HandleNoReturnAttribute(Decl *d, AttributeList *rawAttr) { 2576 // check the attribute arguments. 2577 if (rawAttr->getNumArgs() != 0) { 2578 Diag(rawAttr->getLoc(), diag::err_attribute_wrong_number_arguments, 2579 std::string("0")); 2580 return; 2581 } 2582 2583 FunctionDecl *Fn = dyn_cast<FunctionDecl>(d); 2584 2585 if (!Fn) { 2586 Diag(rawAttr->getLoc(), diag::warn_attribute_wrong_decl_type, 2587 "noreturn", "function"); 2588 return; 2589 } 2590 2591 d->addAttr(new NoReturnAttr()); 2592} 2593 2594void Sema::HandleDeprecatedAttribute(Decl *d, AttributeList *rawAttr) { 2595 // check the attribute arguments. 2596 if (rawAttr->getNumArgs() != 0) { 2597 Diag(rawAttr->getLoc(), diag::err_attribute_wrong_number_arguments, 2598 std::string("0")); 2599 return; 2600 } 2601 2602 d->addAttr(new DeprecatedAttr()); 2603} 2604 2605void Sema::HandleVisibilityAttribute(Decl *d, AttributeList *rawAttr) { 2606 // check the attribute arguments. 2607 if (rawAttr->getNumArgs() != 1) { 2608 Diag(rawAttr->getLoc(), diag::err_attribute_wrong_number_arguments, 2609 std::string("1")); 2610 return; 2611 } 2612 2613 Expr *Arg = static_cast<Expr*>(rawAttr->getArg(0)); 2614 Arg = Arg->IgnoreParenCasts(); 2615 StringLiteral *Str = dyn_cast<StringLiteral>(Arg); 2616 2617 if (Str == 0 || Str->isWide()) { 2618 Diag(rawAttr->getLoc(), diag::err_attribute_argument_n_not_string, 2619 "visibility", std::string("1")); 2620 return; 2621 } 2622 2623 const char *TypeStr = Str->getStrData(); 2624 unsigned TypeLen = Str->getByteLength(); 2625 VisibilityAttr::VisibilityTypes type; 2626 2627 if (TypeLen == 7 && !memcmp(TypeStr, "default", 7)) 2628 type = VisibilityAttr::DefaultVisibility; 2629 else if (TypeLen == 6 && !memcmp(TypeStr, "hidden", 6)) 2630 type = VisibilityAttr::HiddenVisibility; 2631 else if (TypeLen == 8 && !memcmp(TypeStr, "internal", 8)) 2632 type = VisibilityAttr::HiddenVisibility; // FIXME 2633 else if (TypeLen == 9 && !memcmp(TypeStr, "protected", 9)) 2634 type = VisibilityAttr::ProtectedVisibility; 2635 else { 2636 Diag(rawAttr->getLoc(), diag::warn_attribute_type_not_supported, 2637 "visibility", TypeStr); 2638 return; 2639 } 2640 2641 d->addAttr(new VisibilityAttr(type)); 2642} 2643 2644void Sema::HandleWeakAttribute(Decl *d, AttributeList *rawAttr) { 2645 // check the attribute arguments. 2646 if (rawAttr->getNumArgs() != 0) { 2647 Diag(rawAttr->getLoc(), diag::err_attribute_wrong_number_arguments, 2648 std::string("0")); 2649 return; 2650 } 2651 2652 d->addAttr(new WeakAttr()); 2653} 2654 2655void Sema::HandleDLLImportAttribute(Decl *d, AttributeList *rawAttr) { 2656 // check the attribute arguments. 2657 if (rawAttr->getNumArgs() != 0) { 2658 Diag(rawAttr->getLoc(), diag::err_attribute_wrong_number_arguments, 2659 std::string("0")); 2660 return; 2661 } 2662 2663 d->addAttr(new DLLImportAttr()); 2664} 2665 2666void Sema::HandleDLLExportAttribute(Decl *d, AttributeList *rawAttr) { 2667 // check the attribute arguments. 2668 if (rawAttr->getNumArgs() != 0) { 2669 Diag(rawAttr->getLoc(), diag::err_attribute_wrong_number_arguments, 2670 std::string("0")); 2671 return; 2672 } 2673 2674 d->addAttr(new DLLExportAttr()); 2675} 2676 2677void Sema::HandleStdCallAttribute(Decl *d, AttributeList *rawAttr) { 2678 // check the attribute arguments. 2679 if (rawAttr->getNumArgs() != 0) { 2680 Diag(rawAttr->getLoc(), diag::err_attribute_wrong_number_arguments, 2681 std::string("0")); 2682 return; 2683 } 2684 2685 d->addAttr(new StdCallAttr()); 2686} 2687 2688void Sema::HandleFastCallAttribute(Decl *d, AttributeList *rawAttr) { 2689 // check the attribute arguments. 2690 if (rawAttr->getNumArgs() != 0) { 2691 Diag(rawAttr->getLoc(), diag::err_attribute_wrong_number_arguments, 2692 std::string("0")); 2693 return; 2694 } 2695 2696 d->addAttr(new FastCallAttr()); 2697} 2698 2699void Sema::HandleNothrowAttribute(Decl *d, AttributeList *rawAttr) { 2700 // check the attribute arguments. 2701 if (rawAttr->getNumArgs() != 0) { 2702 Diag(rawAttr->getLoc(), diag::err_attribute_wrong_number_arguments, 2703 std::string("0")); 2704 return; 2705 } 2706 2707 d->addAttr(new NoThrowAttr()); 2708} 2709 2710static const FunctionTypeProto *getFunctionProto(Decl *d) { 2711 QualType Ty; 2712 2713 if (ValueDecl *decl = dyn_cast<ValueDecl>(d)) 2714 Ty = decl->getType(); 2715 else if (FieldDecl *decl = dyn_cast<FieldDecl>(d)) 2716 Ty = decl->getType(); 2717 else if (TypedefDecl* decl = dyn_cast<TypedefDecl>(d)) 2718 Ty = decl->getUnderlyingType(); 2719 else 2720 return 0; 2721 2722 if (Ty->isFunctionPointerType()) { 2723 const PointerType *PtrTy = Ty->getAsPointerType(); 2724 Ty = PtrTy->getPointeeType(); 2725 } 2726 2727 if (const FunctionType *FnTy = Ty->getAsFunctionType()) 2728 return dyn_cast<FunctionTypeProto>(FnTy->getAsFunctionType()); 2729 2730 return 0; 2731} 2732 2733static inline bool isNSStringType(QualType T, ASTContext &Ctx) { 2734 if (!T->isPointerType()) 2735 return false; 2736 2737 T = T->getAsPointerType()->getPointeeType().getCanonicalType(); 2738 ObjCInterfaceType* ClsT = dyn_cast<ObjCInterfaceType>(T.getTypePtr()); 2739 2740 if (!ClsT) 2741 return false; 2742 2743 IdentifierInfo* ClsName = ClsT->getDecl()->getIdentifier(); 2744 2745 // FIXME: Should we walk the chain of classes? 2746 return ClsName == &Ctx.Idents.get("NSString") || 2747 ClsName == &Ctx.Idents.get("NSMutableString"); 2748} 2749 2750/// Handle __attribute__((format(type,idx,firstarg))) attributes 2751/// based on http://gcc.gnu.org/onlinedocs/gcc/Function-Attributes.html 2752void Sema::HandleFormatAttribute(Decl *d, AttributeList *rawAttr) { 2753 2754 if (!rawAttr->getParameterName()) { 2755 Diag(rawAttr->getLoc(), diag::err_attribute_argument_n_not_string, 2756 "format", std::string("1")); 2757 return; 2758 } 2759 2760 if (rawAttr->getNumArgs() != 2) { 2761 Diag(rawAttr->getLoc(), diag::err_attribute_wrong_number_arguments, 2762 std::string("3")); 2763 return; 2764 } 2765 2766 // GCC ignores the format attribute on K&R style function 2767 // prototypes, so we ignore it as well 2768 const FunctionTypeProto *proto = getFunctionProto(d); 2769 2770 if (!proto) { 2771 Diag(rawAttr->getLoc(), diag::warn_attribute_wrong_decl_type, 2772 "format", "function"); 2773 return; 2774 } 2775 2776 // FIXME: in C++ the implicit 'this' function parameter also counts. 2777 // this is needed in order to be compatible with GCC 2778 // the index must start in 1 and the limit is numargs+1 2779 unsigned NumArgs = proto->getNumArgs(); 2780 unsigned FirstIdx = 1; 2781 2782 const char *Format = rawAttr->getParameterName()->getName(); 2783 unsigned FormatLen = rawAttr->getParameterName()->getLength(); 2784 2785 // Normalize the argument, __foo__ becomes foo. 2786 if (FormatLen > 4 && Format[0] == '_' && Format[1] == '_' && 2787 Format[FormatLen - 2] == '_' && Format[FormatLen - 1] == '_') { 2788 Format += 2; 2789 FormatLen -= 4; 2790 } 2791 2792 bool Supported = false; 2793 bool is_NSString = false; 2794 bool is_strftime = false; 2795 2796 switch (FormatLen) { 2797 default: break; 2798 case 5: 2799 Supported = !memcmp(Format, "scanf", 5); 2800 break; 2801 case 6: 2802 Supported = !memcmp(Format, "printf", 6); 2803 break; 2804 case 7: 2805 Supported = !memcmp(Format, "strfmon", 7); 2806 break; 2807 case 8: 2808 Supported = (is_strftime = !memcmp(Format, "strftime", 8)) || 2809 (is_NSString = !memcmp(Format, "NSString", 8)); 2810 break; 2811 } 2812 2813 if (!Supported) { 2814 Diag(rawAttr->getLoc(), diag::warn_attribute_type_not_supported, 2815 "format", rawAttr->getParameterName()->getName()); 2816 return; 2817 } 2818 2819 // checks for the 2nd argument 2820 Expr *IdxExpr = static_cast<Expr *>(rawAttr->getArg(0)); 2821 llvm::APSInt Idx(Context.getTypeSize(IdxExpr->getType())); 2822 if (!IdxExpr->isIntegerConstantExpr(Idx, Context)) { 2823 Diag(rawAttr->getLoc(), diag::err_attribute_argument_n_not_int, 2824 "format", std::string("2"), IdxExpr->getSourceRange()); 2825 return; 2826 } 2827 2828 if (Idx.getZExtValue() < FirstIdx || Idx.getZExtValue() > NumArgs) { 2829 Diag(rawAttr->getLoc(), diag::err_attribute_argument_out_of_bounds, 2830 "format", std::string("2"), IdxExpr->getSourceRange()); 2831 return; 2832 } 2833 2834 // FIXME: Do we need to bounds check? 2835 unsigned ArgIdx = Idx.getZExtValue() - 1; 2836 2837 // make sure the format string is really a string 2838 QualType Ty = proto->getArgType(ArgIdx); 2839 2840 if (is_NSString) { 2841 // FIXME: do we need to check if the type is NSString*? What are 2842 // the semantics? 2843 if (!isNSStringType(Ty, Context)) { 2844 // FIXME: Should highlight the actual expression that has the 2845 // wrong type. 2846 Diag(rawAttr->getLoc(), diag::err_format_attribute_not_NSString, 2847 IdxExpr->getSourceRange()); 2848 return; 2849 } 2850 } 2851 else if (!Ty->isPointerType() || 2852 !Ty->getAsPointerType()->getPointeeType()->isCharType()) { 2853 // FIXME: Should highlight the actual expression that has the 2854 // wrong type. 2855 Diag(rawAttr->getLoc(), diag::err_format_attribute_not_string, 2856 IdxExpr->getSourceRange()); 2857 return; 2858 } 2859 2860 // check the 3rd argument 2861 Expr *FirstArgExpr = static_cast<Expr *>(rawAttr->getArg(1)); 2862 llvm::APSInt FirstArg(Context.getTypeSize(FirstArgExpr->getType())); 2863 if (!FirstArgExpr->isIntegerConstantExpr(FirstArg, Context)) { 2864 Diag(rawAttr->getLoc(), diag::err_attribute_argument_n_not_int, 2865 "format", std::string("3"), FirstArgExpr->getSourceRange()); 2866 return; 2867 } 2868 2869 // check if the function is variadic if the 3rd argument non-zero 2870 if (FirstArg != 0) { 2871 if (proto->isVariadic()) { 2872 ++NumArgs; // +1 for ... 2873 } else { 2874 Diag(d->getLocation(), diag::err_format_attribute_requires_variadic); 2875 return; 2876 } 2877 } 2878 2879 // strftime requires FirstArg to be 0 because it doesn't read from any variable 2880 // the input is just the current time + the format string 2881 if (is_strftime) { 2882 if (FirstArg != 0) { 2883 Diag(rawAttr->getLoc(), diag::err_format_strftime_third_parameter, 2884 FirstArgExpr->getSourceRange()); 2885 return; 2886 } 2887 // if 0 it disables parameter checking (to use with e.g. va_list) 2888 } else if (FirstArg != 0 && FirstArg != NumArgs) { 2889 Diag(rawAttr->getLoc(), diag::err_attribute_argument_out_of_bounds, 2890 "format", std::string("3"), FirstArgExpr->getSourceRange()); 2891 return; 2892 } 2893 2894 d->addAttr(new FormatAttr(std::string(Format, FormatLen), 2895 Idx.getZExtValue(), FirstArg.getZExtValue())); 2896} 2897 2898void Sema::HandleTransparentUnionAttribute(Decl *d, AttributeList *rawAttr) { 2899 // check the attribute arguments. 2900 if (rawAttr->getNumArgs() != 0) { 2901 Diag(rawAttr->getLoc(), diag::err_attribute_wrong_number_arguments, 2902 std::string("0")); 2903 return; 2904 } 2905 2906 TypeDecl *decl = dyn_cast<TypeDecl>(d); 2907 2908 if (!decl || !Context.getTypeDeclType(decl)->isUnionType()) { 2909 Diag(rawAttr->getLoc(), diag::warn_attribute_wrong_decl_type, 2910 "transparent_union", "union"); 2911 return; 2912 } 2913 2914 //QualType QTy = Context.getTypeDeclType(decl); 2915 //const RecordType *Ty = QTy->getAsUnionType(); 2916 2917// FIXME 2918// Ty->addAttr(new TransparentUnionAttr()); 2919} 2920 2921void Sema::HandleAnnotateAttribute(Decl *d, AttributeList *rawAttr) { 2922 // check the attribute arguments. 2923 if (rawAttr->getNumArgs() != 1) { 2924 Diag(rawAttr->getLoc(), diag::err_attribute_wrong_number_arguments, 2925 std::string("1")); 2926 return; 2927 } 2928 Expr *argExpr = static_cast<Expr *>(rawAttr->getArg(0)); 2929 StringLiteral *SE = dyn_cast<StringLiteral>(argExpr); 2930 2931 // Make sure that there is a string literal as the annotation's single 2932 // argument. 2933 if (!SE) { 2934 Diag(rawAttr->getLoc(), diag::err_attribute_annotate_no_string); 2935 return; 2936 } 2937 d->addAttr(new AnnotateAttr(std::string(SE->getStrData(), 2938 SE->getByteLength()))); 2939} 2940 2941void Sema::HandleAlignedAttribute(Decl *d, AttributeList *rawAttr) 2942{ 2943 // check the attribute arguments. 2944 if (rawAttr->getNumArgs() > 1) { 2945 Diag(rawAttr->getLoc(), diag::err_attribute_wrong_number_arguments, 2946 std::string("1")); 2947 return; 2948 } 2949 2950 unsigned Align = 0; 2951 2952 if (rawAttr->getNumArgs() == 0) { 2953 // FIXME: This should be the target specific maximum alignment. 2954 // (For now we just use 128 bits which is the maximum on X86. 2955 Align = 128; 2956 return; 2957 } else { 2958 Expr *alignmentExpr = static_cast<Expr *>(rawAttr->getArg(0)); 2959 llvm::APSInt alignment(32); 2960 if (!alignmentExpr->isIntegerConstantExpr(alignment, Context)) { 2961 Diag(rawAttr->getLoc(), diag::err_attribute_argument_not_int, 2962 "aligned", alignmentExpr->getSourceRange()); 2963 return; 2964 } 2965 2966 Align = alignment.getZExtValue() * 8; 2967 } 2968 2969 d->addAttr(new AlignedAttr(Align)); 2970} 2971