SemaDecl.cpp revision 910758ef84473671aa8f63ebef652dd20e81e6e0
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// FIXME: fix this code to cleanup the Old attrs correctly 280 while (attr) { 281 tmp = attr; 282 attr = attr->getNext(); 283 284 if (!DeclHasAttr(New, tmp)) { 285 New->addAttr(tmp); 286 } else { 287 tmp->setNext(0); 288 delete(tmp); 289 } 290 } 291} 292 293/// MergeFunctionDecl - We just parsed a function 'New' from 294/// declarator D which has the same name and scope as a previous 295/// declaration 'Old'. Figure out how to resolve this situation, 296/// merging decls or emitting diagnostics as appropriate. 297/// Redeclaration will be set true if thisNew is a redeclaration OldD. 298FunctionDecl * 299Sema::MergeFunctionDecl(FunctionDecl *New, Decl *OldD, bool &Redeclaration) { 300 Redeclaration = false; 301 // Verify the old decl was also a function. 302 FunctionDecl *Old = dyn_cast<FunctionDecl>(OldD); 303 if (!Old) { 304 Diag(New->getLocation(), diag::err_redefinition_different_kind, 305 New->getName()); 306 Diag(OldD->getLocation(), diag::err_previous_definition); 307 return New; 308 } 309 310 QualType OldQType = Context.getCanonicalType(Old->getType()); 311 QualType NewQType = Context.getCanonicalType(New->getType()); 312 313 // C++ [dcl.fct]p3: 314 // All declarations for a function shall agree exactly in both the 315 // return type and the parameter-type-list. 316 if (getLangOptions().CPlusPlus && OldQType == NewQType) { 317 MergeAttributes(New, Old); 318 Redeclaration = true; 319 return MergeCXXFunctionDecl(New, Old); 320 } 321 322 // C: Function types need to be compatible, not identical. This handles 323 // duplicate function decls like "void f(int); void f(enum X);" properly. 324 if (!getLangOptions().CPlusPlus && 325 Context.functionTypesAreCompatible(OldQType, NewQType)) { 326 MergeAttributes(New, Old); 327 Redeclaration = true; 328 return New; 329 } 330 331 // A function that has already been declared has been redeclared or defined 332 // with a different type- show appropriate diagnostic 333 diag::kind PrevDiag; 334 if (Old->isThisDeclarationADefinition()) 335 PrevDiag = diag::err_previous_definition; 336 else if (Old->isImplicit()) 337 PrevDiag = diag::err_previous_implicit_declaration; 338 else 339 PrevDiag = diag::err_previous_declaration; 340 341 // TODO: CHECK FOR CONFLICTS, multiple decls with same name in one scope. 342 // TODO: This is totally simplistic. It should handle merging functions 343 // together etc, merging extern int X; int X; ... 344 Diag(New->getLocation(), diag::err_conflicting_types, New->getName()); 345 Diag(Old->getLocation(), PrevDiag); 346 return New; 347} 348 349/// equivalentArrayTypes - Used to determine whether two array types are 350/// equivalent. 351/// We need to check this explicitly as an incomplete array definition is 352/// considered a VariableArrayType, so will not match a complete array 353/// definition that would be otherwise equivalent. 354static bool areEquivalentArrayTypes(QualType NewQType, QualType OldQType) { 355 const ArrayType *NewAT = NewQType->getAsArrayType(); 356 const ArrayType *OldAT = OldQType->getAsArrayType(); 357 358 if (!NewAT || !OldAT) 359 return false; 360 361 // If either (or both) array types in incomplete we need to strip off the 362 // outer VariableArrayType. Once the outer VAT is removed the remaining 363 // types must be identical if the array types are to be considered 364 // equivalent. 365 // eg. int[][1] and int[1][1] become 366 // VAT(null, CAT(1, int)) and CAT(1, CAT(1, int)) 367 // removing the outermost VAT gives 368 // CAT(1, int) and CAT(1, int) 369 // which are equal, therefore the array types are equivalent. 370 if (NewAT->isIncompleteArrayType() || OldAT->isIncompleteArrayType()) { 371 if (NewAT->getIndexTypeQualifier() != OldAT->getIndexTypeQualifier()) 372 return false; 373 NewQType = NewAT->getElementType().getCanonicalType(); 374 OldQType = OldAT->getElementType().getCanonicalType(); 375 } 376 377 return NewQType == OldQType; 378} 379 380/// MergeVarDecl - We just parsed a variable 'New' which has the same name 381/// and scope as a previous declaration 'Old'. Figure out how to resolve this 382/// situation, merging decls or emitting diagnostics as appropriate. 383/// 384/// FIXME: Need to carefully consider tentative definition rules (C99 6.9.2p2). 385/// For example, we incorrectly complain about i1, i4 from C99 6.9.2p4. 386/// 387VarDecl *Sema::MergeVarDecl(VarDecl *New, Decl *OldD) { 388 // Verify the old decl was also a variable. 389 VarDecl *Old = dyn_cast<VarDecl>(OldD); 390 if (!Old) { 391 Diag(New->getLocation(), diag::err_redefinition_different_kind, 392 New->getName()); 393 Diag(OldD->getLocation(), diag::err_previous_definition); 394 return New; 395 } 396 397 MergeAttributes(New, Old); 398 399 // Verify the types match. 400 QualType OldCType = Context.getCanonicalType(Old->getType()); 401 QualType NewCType = Context.getCanonicalType(New->getType()); 402 if (OldCType != NewCType && !areEquivalentArrayTypes(NewCType, OldCType)) { 403 Diag(New->getLocation(), diag::err_redefinition, New->getName()); 404 Diag(Old->getLocation(), diag::err_previous_definition); 405 return New; 406 } 407 // C99 6.2.2p4: Check if we have a static decl followed by a non-static. 408 if (New->getStorageClass() == VarDecl::Static && 409 (Old->getStorageClass() == VarDecl::None || 410 Old->getStorageClass() == VarDecl::Extern)) { 411 Diag(New->getLocation(), diag::err_static_non_static, New->getName()); 412 Diag(Old->getLocation(), diag::err_previous_definition); 413 return New; 414 } 415 // C99 6.2.2p4: Check if we have a non-static decl followed by a static. 416 if (New->getStorageClass() != VarDecl::Static && 417 Old->getStorageClass() == VarDecl::Static) { 418 Diag(New->getLocation(), diag::err_non_static_static, New->getName()); 419 Diag(Old->getLocation(), diag::err_previous_definition); 420 return New; 421 } 422 // We've verified the types match, now handle "tentative" definitions. 423 if (Old->isFileVarDecl() && New->isFileVarDecl()) { 424 // Handle C "tentative" external object definitions (C99 6.9.2). 425 bool OldIsTentative = false; 426 bool NewIsTentative = false; 427 428 if (!Old->getInit() && 429 (Old->getStorageClass() == VarDecl::None || 430 Old->getStorageClass() == VarDecl::Static)) 431 OldIsTentative = true; 432 433 // FIXME: this check doesn't work (since the initializer hasn't been 434 // attached yet). This check should be moved to FinalizeDeclaratorGroup. 435 // Unfortunately, by the time we get to FinializeDeclaratorGroup, we've 436 // thrown out the old decl. 437 if (!New->getInit() && 438 (New->getStorageClass() == VarDecl::None || 439 New->getStorageClass() == VarDecl::Static)) 440 ; // change to NewIsTentative = true; once the code is moved. 441 442 if (NewIsTentative || OldIsTentative) 443 return New; 444 } 445 // Handle __private_extern__ just like extern. 446 if (Old->getStorageClass() != VarDecl::Extern && 447 Old->getStorageClass() != VarDecl::PrivateExtern && 448 New->getStorageClass() != VarDecl::Extern && 449 New->getStorageClass() != VarDecl::PrivateExtern) { 450 Diag(New->getLocation(), diag::err_redefinition, New->getName()); 451 Diag(Old->getLocation(), diag::err_previous_definition); 452 } 453 return New; 454} 455 456/// CheckParmsForFunctionDef - Check that the parameters of the given 457/// function are appropriate for the definition of a function. This 458/// takes care of any checks that cannot be performed on the 459/// declaration itself, e.g., that the types of each of the function 460/// parameters are complete. 461bool Sema::CheckParmsForFunctionDef(FunctionDecl *FD) { 462 bool HasInvalidParm = false; 463 for (unsigned p = 0, NumParams = FD->getNumParams(); p < NumParams; ++p) { 464 ParmVarDecl *Param = FD->getParamDecl(p); 465 466 // C99 6.7.5.3p4: the parameters in a parameter type list in a 467 // function declarator that is part of a function definition of 468 // that function shall not have incomplete type. 469 if (Param->getType()->isIncompleteType() && 470 !Param->isInvalidDecl()) { 471 Diag(Param->getLocation(), diag::err_typecheck_decl_incomplete_type, 472 Param->getType().getAsString()); 473 Param->setInvalidDecl(); 474 HasInvalidParm = true; 475 } 476 } 477 478 return HasInvalidParm; 479} 480 481/// CreateImplicitParameter - Creates an implicit function parameter 482/// in the scope S and with the given type. This routine is used, for 483/// example, to create the implicit "self" parameter in an Objective-C 484/// method. 485ParmVarDecl * 486Sema::CreateImplicitParameter(Scope *S, IdentifierInfo *Id, 487 SourceLocation IdLoc, QualType Type) { 488 ParmVarDecl *New = ParmVarDecl::Create(Context, CurContext, IdLoc, Id, Type, 489 VarDecl::None, 0, 0); 490 if (Id) 491 PushOnScopeChains(New, S); 492 493 return New; 494} 495 496/// ParsedFreeStandingDeclSpec - This method is invoked when a declspec with 497/// no declarator (e.g. "struct foo;") is parsed. 498Sema::DeclTy *Sema::ParsedFreeStandingDeclSpec(Scope *S, DeclSpec &DS) { 499 // TODO: emit error on 'int;' or 'const enum foo;'. 500 // TODO: emit error on 'typedef int;' 501 // if (!DS.isMissingDeclaratorOk()) Diag(...); 502 503 return dyn_cast_or_null<TagDecl>(static_cast<Decl *>(DS.getTypeRep())); 504} 505 506bool Sema::CheckSingleInitializer(Expr *&Init, QualType DeclType) { 507 // Get the type before calling CheckSingleAssignmentConstraints(), since 508 // it can promote the expression. 509 QualType InitType = Init->getType(); 510 511 AssignConvertType ConvTy = CheckSingleAssignmentConstraints(DeclType, Init); 512 return DiagnoseAssignmentResult(ConvTy, Init->getLocStart(), DeclType, 513 InitType, Init, "initializing"); 514} 515 516bool Sema::CheckInitExpr(Expr *expr, InitListExpr *IList, unsigned slot, 517 QualType ElementType) { 518 Expr *savExpr = expr; // Might be promoted by CheckSingleInitializer. 519 if (CheckSingleInitializer(expr, ElementType)) 520 return true; // types weren't compatible. 521 522 if (savExpr != expr) // The type was promoted, update initializer list. 523 IList->setInit(slot, expr); 524 return false; 525} 526 527bool Sema::CheckStringLiteralInit(StringLiteral *strLiteral, QualType &DeclT) { 528 if (const IncompleteArrayType *IAT = DeclT->getAsIncompleteArrayType()) { 529 // C99 6.7.8p14. We have an array of character type with unknown size 530 // being initialized to a string literal. 531 llvm::APSInt ConstVal(32); 532 ConstVal = strLiteral->getByteLength() + 1; 533 // Return a new array type (C99 6.7.8p22). 534 DeclT = Context.getConstantArrayType(IAT->getElementType(), ConstVal, 535 ArrayType::Normal, 0); 536 } else if (const ConstantArrayType *CAT = DeclT->getAsConstantArrayType()) { 537 // C99 6.7.8p14. We have an array of character type with known size. 538 if (strLiteral->getByteLength() > (unsigned)CAT->getMaximumElements()) 539 Diag(strLiteral->getSourceRange().getBegin(), 540 diag::warn_initializer_string_for_char_array_too_long, 541 strLiteral->getSourceRange()); 542 } else { 543 assert(0 && "HandleStringLiteralInit(): Invalid array type"); 544 } 545 // Set type from "char *" to "constant array of char". 546 strLiteral->setType(DeclT); 547 // For now, we always return false (meaning success). 548 return false; 549} 550 551StringLiteral *Sema::IsStringLiteralInit(Expr *Init, QualType DeclType) { 552 const ArrayType *AT = DeclType->getAsArrayType(); 553 if (AT && AT->getElementType()->isCharType()) { 554 return dyn_cast<StringLiteral>(Init); 555 } 556 return 0; 557} 558 559// CheckInitializerListTypes - Checks the types of elements of an initializer 560// list. This function is recursive: it calls itself to initialize subelements 561// of aggregate types. Note that the topLevel parameter essentially refers to 562// whether this expression "owns" the initializer list passed in, or if this 563// initialization is taking elements out of a parent initializer. Each 564// call to this function adds zero or more to startIndex, reports any errors, 565// and returns true if it found any inconsistent types. 566bool Sema::CheckInitializerListTypes(InitListExpr*& IList, QualType &DeclType, 567 bool topLevel, unsigned& startIndex) { 568 bool hadError = false; 569 570 if (DeclType->isScalarType()) { 571 // The simplest case: initializing a single scalar 572 if (topLevel) { 573 Diag(IList->getLocStart(), diag::warn_braces_around_scalar_init, 574 IList->getSourceRange()); 575 } 576 if (startIndex < IList->getNumInits()) { 577 Expr* expr = IList->getInit(startIndex); 578 if (InitListExpr *SubInitList = dyn_cast<InitListExpr>(expr)) { 579 // FIXME: Should an error be reported here instead? 580 unsigned newIndex = 0; 581 CheckInitializerListTypes(SubInitList, DeclType, true, newIndex); 582 } else { 583 hadError |= CheckInitExpr(expr, IList, startIndex, DeclType); 584 } 585 ++startIndex; 586 } 587 // FIXME: Should an error be reported for empty initializer list + scalar? 588 } else if (DeclType->isVectorType()) { 589 if (startIndex < IList->getNumInits()) { 590 const VectorType *VT = DeclType->getAsVectorType(); 591 int maxElements = VT->getNumElements(); 592 QualType elementType = VT->getElementType(); 593 594 for (int i = 0; i < maxElements; ++i) { 595 // Don't attempt to go past the end of the init list 596 if (startIndex >= IList->getNumInits()) 597 break; 598 Expr* expr = IList->getInit(startIndex); 599 if (InitListExpr *SubInitList = dyn_cast<InitListExpr>(expr)) { 600 unsigned newIndex = 0; 601 hadError |= CheckInitializerListTypes(SubInitList, elementType, 602 true, newIndex); 603 ++startIndex; 604 } else { 605 hadError |= CheckInitializerListTypes(IList, elementType, 606 false, startIndex); 607 } 608 } 609 } 610 } else if (DeclType->isAggregateType() || DeclType->isUnionType()) { 611 if (DeclType->isStructureType() || DeclType->isUnionType()) { 612 if (startIndex < IList->getNumInits() && !topLevel && 613 Context.typesAreCompatible(IList->getInit(startIndex)->getType(), 614 DeclType)) { 615 // We found a compatible struct; per the standard, this initializes the 616 // struct. (The C standard technically says that this only applies for 617 // initializers for declarations with automatic scope; however, this 618 // construct is unambiguous anyway because a struct cannot contain 619 // a type compatible with itself. We'll output an error when we check 620 // if the initializer is constant.) 621 // FIXME: Is a call to CheckSingleInitializer required here? 622 ++startIndex; 623 } else { 624 RecordDecl* structDecl = DeclType->getAsRecordType()->getDecl(); 625 626 // If the record is invalid, some of it's members are invalid. To avoid 627 // confusion, we forgo checking the intializer for the entire record. 628 if (structDecl->isInvalidDecl()) 629 return true; 630 631 // If structDecl is a forward declaration, this loop won't do anything; 632 // That's okay, because an error should get printed out elsewhere. It 633 // might be worthwhile to skip over the rest of the initializer, though. 634 int numMembers = structDecl->getNumMembers() - 635 structDecl->hasFlexibleArrayMember(); 636 for (int i = 0; i < numMembers; i++) { 637 // Don't attempt to go past the end of the init list 638 if (startIndex >= IList->getNumInits()) 639 break; 640 FieldDecl * curField = structDecl->getMember(i); 641 if (!curField->getIdentifier()) { 642 // Don't initialize unnamed fields, e.g. "int : 20;" 643 continue; 644 } 645 QualType fieldType = curField->getType(); 646 Expr* expr = IList->getInit(startIndex); 647 if (InitListExpr *SubInitList = dyn_cast<InitListExpr>(expr)) { 648 unsigned newStart = 0; 649 hadError |= CheckInitializerListTypes(SubInitList, fieldType, 650 true, newStart); 651 ++startIndex; 652 } else { 653 hadError |= CheckInitializerListTypes(IList, fieldType, 654 false, startIndex); 655 } 656 if (DeclType->isUnionType()) 657 break; 658 } 659 // FIXME: Implement flexible array initialization GCC extension (it's a 660 // really messy extension to implement, unfortunately...the necessary 661 // information isn't actually even here!) 662 } 663 } else if (DeclType->isArrayType()) { 664 // Check for the special-case of initializing an array with a string. 665 if (startIndex < IList->getNumInits()) { 666 if (StringLiteral *lit = IsStringLiteralInit(IList->getInit(startIndex), 667 DeclType)) { 668 CheckStringLiteralInit(lit, DeclType); 669 ++startIndex; 670 if (topLevel && startIndex < IList->getNumInits()) { 671 // We have leftover initializers; warn 672 Diag(IList->getInit(startIndex)->getLocStart(), 673 diag::err_excess_initializers_in_char_array_initializer, 674 IList->getInit(startIndex)->getSourceRange()); 675 } 676 return false; 677 } 678 } 679 int maxElements; 680 if (DeclType->isIncompleteArrayType()) { 681 // FIXME: use a proper constant 682 maxElements = 0x7FFFFFFF; 683 } else if (const VariableArrayType *VAT = 684 DeclType->getAsVariableArrayType()) { 685 // Check for VLAs; in standard C it would be possible to check this 686 // earlier, but I don't know where clang accepts VLAs (gcc accepts 687 // them in all sorts of strange places). 688 Diag(VAT->getSizeExpr()->getLocStart(), 689 diag::err_variable_object_no_init, 690 VAT->getSizeExpr()->getSourceRange()); 691 hadError = true; 692 maxElements = 0x7FFFFFFF; 693 } else { 694 const ConstantArrayType *CAT = DeclType->getAsConstantArrayType(); 695 maxElements = static_cast<int>(CAT->getSize().getZExtValue()); 696 } 697 QualType elementType = DeclType->getAsArrayType()->getElementType(); 698 int numElements = 0; 699 for (int i = 0; i < maxElements; ++i, ++numElements) { 700 // Don't attempt to go past the end of the init list 701 if (startIndex >= IList->getNumInits()) 702 break; 703 Expr* expr = IList->getInit(startIndex); 704 if (InitListExpr *SubInitList = dyn_cast<InitListExpr>(expr)) { 705 unsigned newIndex = 0; 706 hadError |= CheckInitializerListTypes(SubInitList, elementType, 707 true, newIndex); 708 ++startIndex; 709 } else { 710 hadError |= CheckInitializerListTypes(IList, elementType, 711 false, startIndex); 712 } 713 } 714 if (DeclType->isIncompleteArrayType()) { 715 // If this is an incomplete array type, the actual type needs to 716 // be calculated here 717 if (numElements == 0) { 718 // Sizing an array implicitly to zero is not allowed 719 // (It could in theory be allowed, but it doesn't really matter.) 720 Diag(IList->getLocStart(), 721 diag::err_at_least_one_initializer_needed_to_size_array); 722 hadError = true; 723 } else { 724 llvm::APSInt ConstVal(32); 725 ConstVal = numElements; 726 DeclType = Context.getConstantArrayType(elementType, ConstVal, 727 ArrayType::Normal, 0); 728 } 729 } 730 } else { 731 assert(0 && "Aggregate that isn't a function or array?!"); 732 } 733 } else { 734 // In C, all types are either scalars or aggregates, but 735 // additional handling is needed here for C++ (and possibly others?). 736 assert(0 && "Unsupported initializer type"); 737 } 738 739 // If this init list is a base list, we set the type; an initializer doesn't 740 // fundamentally have a type, but this makes the ASTs a bit easier to read 741 if (topLevel) 742 IList->setType(DeclType); 743 744 if (topLevel && startIndex < IList->getNumInits()) { 745 // We have leftover initializers; warn 746 Diag(IList->getInit(startIndex)->getLocStart(), 747 diag::warn_excess_initializers, 748 IList->getInit(startIndex)->getSourceRange()); 749 } 750 return hadError; 751} 752 753bool Sema::CheckInitializerTypes(Expr *&Init, QualType &DeclType) { 754 // C99 6.7.8p3: The type of the entity to be initialized shall be an array 755 // of unknown size ("[]") or an object type that is not a variable array type. 756 if (const VariableArrayType *VAT = DeclType->getAsVariableArrayType()) 757 return Diag(VAT->getSizeExpr()->getLocStart(), 758 diag::err_variable_object_no_init, 759 VAT->getSizeExpr()->getSourceRange()); 760 761 InitListExpr *InitList = dyn_cast<InitListExpr>(Init); 762 if (!InitList) { 763 // FIXME: Handle wide strings 764 if (StringLiteral *strLiteral = IsStringLiteralInit(Init, DeclType)) 765 return CheckStringLiteralInit(strLiteral, DeclType); 766 767 if (DeclType->isArrayType()) 768 return Diag(Init->getLocStart(), 769 diag::err_array_init_list_required, 770 Init->getSourceRange()); 771 772 return CheckSingleInitializer(Init, DeclType); 773 } 774#if 0 775 unsigned newIndex = 0; 776 return CheckInitializerListTypes(InitList, DeclType, true, newIndex); 777#else 778 InitListChecker CheckInitList(this, InitList, DeclType); 779 return CheckInitList.HadError(); 780#endif 781} 782 783Sema::DeclTy * 784Sema::ActOnDeclarator(Scope *S, Declarator &D, DeclTy *lastDecl) { 785 ScopedDecl *LastDeclarator = dyn_cast_or_null<ScopedDecl>((Decl *)lastDecl); 786 IdentifierInfo *II = D.getIdentifier(); 787 788 // All of these full declarators require an identifier. If it doesn't have 789 // one, the ParsedFreeStandingDeclSpec action should be used. 790 if (II == 0) { 791 Diag(D.getDeclSpec().getSourceRange().getBegin(), 792 diag::err_declarator_need_ident, 793 D.getDeclSpec().getSourceRange(), D.getSourceRange()); 794 return 0; 795 } 796 797 // The scope passed in may not be a decl scope. Zip up the scope tree until 798 // we find one that is. 799 while ((S->getFlags() & Scope::DeclScope) == 0) 800 S = S->getParent(); 801 802 // See if this is a redefinition of a variable in the same scope. 803 Decl *PrevDecl = LookupDecl(II, Decl::IDNS_Ordinary, S); 804 ScopedDecl *New; 805 bool InvalidDecl = false; 806 807 // In C++, the previous declaration we find might be a tag type 808 // (class or enum). In this case, the new declaration will hide the 809 // tag type. 810 if (PrevDecl && PrevDecl->getIdentifierNamespace() == Decl::IDNS_Tag) 811 PrevDecl = 0; 812 813 QualType R = GetTypeForDeclarator(D, S); 814 assert(!R.isNull() && "GetTypeForDeclarator() returned null type"); 815 816 if (D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_typedef) { 817 // Check that there are no default arguments (C++ only). 818 if (getLangOptions().CPlusPlus) 819 CheckExtraCXXDefaultArguments(D); 820 821 TypedefDecl *NewTD = ParseTypedefDecl(S, D, R, LastDeclarator); 822 if (!NewTD) return 0; 823 824 // Handle attributes prior to checking for duplicates in MergeVarDecl 825 HandleDeclAttributes(NewTD, D.getDeclSpec().getAttributes(), 826 D.getAttributes()); 827 // Merge the decl with the existing one if appropriate. If the decl is 828 // in an outer scope, it isn't the same thing. 829 if (PrevDecl && IdResolver.isDeclInScope(PrevDecl, CurContext, S)) { 830 NewTD = MergeTypeDefDecl(NewTD, PrevDecl); 831 if (NewTD == 0) return 0; 832 } 833 New = NewTD; 834 if (S->getFnParent() == 0) { 835 // C99 6.7.7p2: If a typedef name specifies a variably modified type 836 // then it shall have block scope. 837 if (NewTD->getUnderlyingType()->isVariablyModifiedType()) { 838 // FIXME: Diagnostic needs to be fixed. 839 Diag(D.getIdentifierLoc(), diag::err_typecheck_illegal_vla); 840 InvalidDecl = true; 841 } 842 } 843 } else if (R.getTypePtr()->isFunctionType()) { 844 FunctionDecl::StorageClass SC = FunctionDecl::None; 845 switch (D.getDeclSpec().getStorageClassSpec()) { 846 default: assert(0 && "Unknown storage class!"); 847 case DeclSpec::SCS_auto: 848 case DeclSpec::SCS_register: 849 Diag(D.getIdentifierLoc(), diag::err_typecheck_sclass_func, 850 R.getAsString()); 851 InvalidDecl = true; 852 break; 853 case DeclSpec::SCS_unspecified: SC = FunctionDecl::None; break; 854 case DeclSpec::SCS_extern: SC = FunctionDecl::Extern; break; 855 case DeclSpec::SCS_static: SC = FunctionDecl::Static; break; 856 case DeclSpec::SCS_private_extern: SC = FunctionDecl::PrivateExtern;break; 857 } 858 859 bool isInline = D.getDeclSpec().isInlineSpecified(); 860 FunctionDecl *NewFD = FunctionDecl::Create(Context, CurContext, 861 D.getIdentifierLoc(), 862 II, R, SC, isInline, 863 LastDeclarator); 864 // Handle attributes. 865 HandleDeclAttributes(NewFD, D.getDeclSpec().getAttributes(), 866 D.getAttributes()); 867 868 // Copy the parameter declarations from the declarator D to 869 // the function declaration NewFD, if they are available. 870 if (D.getNumTypeObjects() > 0 && 871 D.getTypeObject(0).Fun.hasPrototype) { 872 DeclaratorChunk::FunctionTypeInfo &FTI = D.getTypeObject(0).Fun; 873 874 // Create Decl objects for each parameter, adding them to the 875 // FunctionDecl. 876 llvm::SmallVector<ParmVarDecl*, 16> Params; 877 878 // Check for C99 6.7.5.3p10 - foo(void) is a non-varargs 879 // function that takes no arguments, not a function that takes a 880 // single void argument. 881 // We let through "const void" here because Sema::GetTypeForDeclarator 882 // already checks for that case. 883 if (FTI.NumArgs == 1 && !FTI.isVariadic && FTI.ArgInfo[0].Ident == 0 && 884 FTI.ArgInfo[0].Param && 885 ((ParmVarDecl*)FTI.ArgInfo[0].Param)->getType()->isVoidType()) { 886 // empty arg list, don't push any params. 887 ParmVarDecl *Param = (ParmVarDecl*)FTI.ArgInfo[0].Param; 888 889 // In C++, the empty parameter-type-list must be spelled "void"; a 890 // typedef of void is not permitted. 891 if (getLangOptions().CPlusPlus && 892 Param->getType().getUnqualifiedType() != Context.VoidTy) { 893 Diag(Param->getLocation(), diag::ext_param_typedef_of_void); 894 } 895 896 } else { 897 for (unsigned i = 0, e = FTI.NumArgs; i != e; ++i) 898 Params.push_back((ParmVarDecl *)FTI.ArgInfo[i].Param); 899 } 900 901 NewFD->setParams(&Params[0], Params.size()); 902 } 903 904 // Merge the decl with the existing one if appropriate. Since C functions 905 // are in a flat namespace, make sure we consider decls in outer scopes. 906 if (PrevDecl && 907 (!getLangOptions().CPlusPlus || 908 IdResolver.isDeclInScope(PrevDecl, CurContext, S)) ) { 909 bool Redeclaration = false; 910 NewFD = MergeFunctionDecl(NewFD, PrevDecl, Redeclaration); 911 if (NewFD == 0) return 0; 912 if (Redeclaration) { 913 // Note that the new declaration is a redeclaration of the 914 // older declaration. Then return the older declaration: the 915 // new one is only kept within the set of previous 916 // declarations for this function. 917 FunctionDecl *OldFD = (FunctionDecl *)PrevDecl; 918 OldFD->AddRedeclaration(NewFD); 919 return OldFD; 920 } 921 } 922 New = NewFD; 923 924 // In C++, check default arguments now that we have merged decls. 925 if (getLangOptions().CPlusPlus) 926 CheckCXXDefaultArguments(NewFD); 927 } else { 928 // Check that there are no default arguments (C++ only). 929 if (getLangOptions().CPlusPlus) 930 CheckExtraCXXDefaultArguments(D); 931 932 if (R.getTypePtr()->isObjCInterfaceType()) { 933 Diag(D.getIdentifierLoc(), diag::err_statically_allocated_object, 934 D.getIdentifier()->getName()); 935 InvalidDecl = true; 936 } 937 938 VarDecl *NewVD; 939 VarDecl::StorageClass SC; 940 switch (D.getDeclSpec().getStorageClassSpec()) { 941 default: assert(0 && "Unknown storage class!"); 942 case DeclSpec::SCS_unspecified: SC = VarDecl::None; break; 943 case DeclSpec::SCS_extern: SC = VarDecl::Extern; break; 944 case DeclSpec::SCS_static: SC = VarDecl::Static; break; 945 case DeclSpec::SCS_auto: SC = VarDecl::Auto; break; 946 case DeclSpec::SCS_register: SC = VarDecl::Register; break; 947 case DeclSpec::SCS_private_extern: SC = VarDecl::PrivateExtern; break; 948 } 949 if (S->getFnParent() == 0) { 950 // C99 6.9p2: The storage-class specifiers auto and register shall not 951 // appear in the declaration specifiers in an external declaration. 952 if (SC == VarDecl::Auto || SC == VarDecl::Register) { 953 Diag(D.getIdentifierLoc(), diag::err_typecheck_sclass_fscope, 954 R.getAsString()); 955 InvalidDecl = true; 956 } 957 NewVD = VarDecl::Create(Context, CurContext, D.getIdentifierLoc(), 958 II, R, SC, LastDeclarator); 959 } else { 960 NewVD = VarDecl::Create(Context, CurContext, D.getIdentifierLoc(), 961 II, R, SC, LastDeclarator); 962 } 963 // Handle attributes prior to checking for duplicates in MergeVarDecl 964 HandleDeclAttributes(NewVD, D.getDeclSpec().getAttributes(), 965 D.getAttributes()); 966 967 // Emit an error if an address space was applied to decl with local storage. 968 // This includes arrays of objects with address space qualifiers, but not 969 // automatic variables that point to other address spaces. 970 // ISO/IEC TR 18037 S5.1.2 971 if (NewVD->hasLocalStorage() && (NewVD->getType().getAddressSpace() != 0)) { 972 Diag(D.getIdentifierLoc(), diag::err_as_qualified_auto_decl); 973 InvalidDecl = true; 974 } 975 // Merge the decl with the existing one if appropriate. If the decl is 976 // in an outer scope, it isn't the same thing. 977 if (PrevDecl && IdResolver.isDeclInScope(PrevDecl, CurContext, S)) { 978 NewVD = MergeVarDecl(NewVD, PrevDecl); 979 if (NewVD == 0) return 0; 980 } 981 New = NewVD; 982 } 983 984 // If this has an identifier, add it to the scope stack. 985 if (II) 986 PushOnScopeChains(New, S); 987 // If any semantic error occurred, mark the decl as invalid. 988 if (D.getInvalidType() || InvalidDecl) 989 New->setInvalidDecl(); 990 991 return New; 992} 993 994bool Sema::CheckAddressConstantExpressionLValue(const Expr* Init) { 995 switch (Init->getStmtClass()) { 996 default: 997 Diag(Init->getExprLoc(), 998 diag::err_init_element_not_constant, Init->getSourceRange()); 999 return true; 1000 case Expr::ParenExprClass: { 1001 const ParenExpr* PE = cast<ParenExpr>(Init); 1002 return CheckAddressConstantExpressionLValue(PE->getSubExpr()); 1003 } 1004 case Expr::CompoundLiteralExprClass: 1005 return cast<CompoundLiteralExpr>(Init)->isFileScope(); 1006 case Expr::DeclRefExprClass: { 1007 const Decl *D = cast<DeclRefExpr>(Init)->getDecl(); 1008 if (const VarDecl *VD = dyn_cast<VarDecl>(D)) { 1009 if (VD->hasGlobalStorage()) 1010 return false; 1011 Diag(Init->getExprLoc(), 1012 diag::err_init_element_not_constant, Init->getSourceRange()); 1013 return true; 1014 } 1015 if (isa<FunctionDecl>(D)) 1016 return false; 1017 Diag(Init->getExprLoc(), 1018 diag::err_init_element_not_constant, Init->getSourceRange()); 1019 return true; 1020 } 1021 case Expr::MemberExprClass: { 1022 const MemberExpr *M = cast<MemberExpr>(Init); 1023 if (M->isArrow()) 1024 return CheckAddressConstantExpression(M->getBase()); 1025 return CheckAddressConstantExpressionLValue(M->getBase()); 1026 } 1027 case Expr::ArraySubscriptExprClass: { 1028 // FIXME: Should we pedwarn for "x[0+0]" (where x is a pointer)? 1029 const ArraySubscriptExpr *ASE = cast<ArraySubscriptExpr>(Init); 1030 return CheckAddressConstantExpression(ASE->getBase()) || 1031 CheckArithmeticConstantExpression(ASE->getIdx()); 1032 } 1033 case Expr::StringLiteralClass: 1034 case Expr::PreDefinedExprClass: 1035 return false; 1036 case Expr::UnaryOperatorClass: { 1037 const UnaryOperator *Exp = cast<UnaryOperator>(Init); 1038 1039 // C99 6.6p9 1040 if (Exp->getOpcode() == UnaryOperator::Deref) 1041 return CheckAddressConstantExpression(Exp->getSubExpr()); 1042 1043 Diag(Init->getExprLoc(), 1044 diag::err_init_element_not_constant, Init->getSourceRange()); 1045 return true; 1046 } 1047 } 1048} 1049 1050bool Sema::CheckAddressConstantExpression(const Expr* Init) { 1051 switch (Init->getStmtClass()) { 1052 default: 1053 Diag(Init->getExprLoc(), 1054 diag::err_init_element_not_constant, Init->getSourceRange()); 1055 return true; 1056 case Expr::ParenExprClass: { 1057 const ParenExpr* PE = cast<ParenExpr>(Init); 1058 return CheckAddressConstantExpression(PE->getSubExpr()); 1059 } 1060 case Expr::StringLiteralClass: 1061 case Expr::ObjCStringLiteralClass: 1062 return false; 1063 case Expr::CallExprClass: { 1064 const CallExpr *CE = cast<CallExpr>(Init); 1065 if (CE->isBuiltinConstantExpr()) 1066 return false; 1067 Diag(Init->getExprLoc(), 1068 diag::err_init_element_not_constant, Init->getSourceRange()); 1069 return true; 1070 } 1071 case Expr::UnaryOperatorClass: { 1072 const UnaryOperator *Exp = cast<UnaryOperator>(Init); 1073 1074 // C99 6.6p9 1075 if (Exp->getOpcode() == UnaryOperator::AddrOf) 1076 return CheckAddressConstantExpressionLValue(Exp->getSubExpr()); 1077 1078 if (Exp->getOpcode() == UnaryOperator::Extension) 1079 return CheckAddressConstantExpression(Exp->getSubExpr()); 1080 1081 Diag(Init->getExprLoc(), 1082 diag::err_init_element_not_constant, Init->getSourceRange()); 1083 return true; 1084 } 1085 case Expr::BinaryOperatorClass: { 1086 // FIXME: Should we pedwarn for expressions like "a + 1 + 2"? 1087 const BinaryOperator *Exp = cast<BinaryOperator>(Init); 1088 1089 Expr *PExp = Exp->getLHS(); 1090 Expr *IExp = Exp->getRHS(); 1091 if (IExp->getType()->isPointerType()) 1092 std::swap(PExp, IExp); 1093 1094 // FIXME: Should we pedwarn if IExp isn't an integer constant expression? 1095 return CheckAddressConstantExpression(PExp) || 1096 CheckArithmeticConstantExpression(IExp); 1097 } 1098 case Expr::ImplicitCastExprClass: { 1099 const Expr* SubExpr = cast<ImplicitCastExpr>(Init)->getSubExpr(); 1100 1101 // Check for implicit promotion 1102 if (SubExpr->getType()->isFunctionType() || 1103 SubExpr->getType()->isArrayType()) 1104 return CheckAddressConstantExpressionLValue(SubExpr); 1105 1106 // Check for pointer->pointer cast 1107 if (SubExpr->getType()->isPointerType()) 1108 return CheckAddressConstantExpression(SubExpr); 1109 1110 if (SubExpr->getType()->isArithmeticType()) 1111 return CheckArithmeticConstantExpression(SubExpr); 1112 1113 Diag(Init->getExprLoc(), 1114 diag::err_init_element_not_constant, Init->getSourceRange()); 1115 return true; 1116 } 1117 case Expr::CastExprClass: { 1118 const Expr* SubExpr = cast<CastExpr>(Init)->getSubExpr(); 1119 1120 // Check for pointer->pointer cast 1121 if (SubExpr->getType()->isPointerType()) 1122 return CheckAddressConstantExpression(SubExpr); 1123 1124 // FIXME: Should we pedwarn for (int*)(0+0)? 1125 if (SubExpr->getType()->isArithmeticType()) 1126 return CheckArithmeticConstantExpression(SubExpr); 1127 1128 Diag(Init->getExprLoc(), 1129 diag::err_init_element_not_constant, Init->getSourceRange()); 1130 return true; 1131 } 1132 case Expr::ConditionalOperatorClass: { 1133 // FIXME: Should we pedwarn here? 1134 const ConditionalOperator *Exp = cast<ConditionalOperator>(Init); 1135 if (!Exp->getCond()->getType()->isArithmeticType()) { 1136 Diag(Init->getExprLoc(), 1137 diag::err_init_element_not_constant, Init->getSourceRange()); 1138 return true; 1139 } 1140 if (CheckArithmeticConstantExpression(Exp->getCond())) 1141 return true; 1142 if (Exp->getLHS() && 1143 CheckAddressConstantExpression(Exp->getLHS())) 1144 return true; 1145 return CheckAddressConstantExpression(Exp->getRHS()); 1146 } 1147 case Expr::AddrLabelExprClass: 1148 return false; 1149 } 1150} 1151 1152bool Sema::CheckArithmeticConstantExpression(const Expr* Init) { 1153 switch (Init->getStmtClass()) { 1154 default: 1155 Diag(Init->getExprLoc(), 1156 diag::err_init_element_not_constant, Init->getSourceRange()); 1157 return true; 1158 case Expr::ParenExprClass: { 1159 const ParenExpr* PE = cast<ParenExpr>(Init); 1160 return CheckArithmeticConstantExpression(PE->getSubExpr()); 1161 } 1162 case Expr::FloatingLiteralClass: 1163 case Expr::IntegerLiteralClass: 1164 case Expr::CharacterLiteralClass: 1165 case Expr::ImaginaryLiteralClass: 1166 case Expr::TypesCompatibleExprClass: 1167 case Expr::CXXBoolLiteralExprClass: 1168 return false; 1169 case Expr::CallExprClass: { 1170 const CallExpr *CE = cast<CallExpr>(Init); 1171 if (CE->isBuiltinConstantExpr()) 1172 return false; 1173 Diag(Init->getExprLoc(), 1174 diag::err_init_element_not_constant, Init->getSourceRange()); 1175 return true; 1176 } 1177 case Expr::DeclRefExprClass: { 1178 const Decl *D = cast<DeclRefExpr>(Init)->getDecl(); 1179 if (isa<EnumConstantDecl>(D)) 1180 return false; 1181 Diag(Init->getExprLoc(), 1182 diag::err_init_element_not_constant, Init->getSourceRange()); 1183 return true; 1184 } 1185 case Expr::CompoundLiteralExprClass: 1186 // Allow "(vector type){2,4}"; normal C constraints don't allow this, 1187 // but vectors are allowed to be magic. 1188 if (Init->getType()->isVectorType()) 1189 return false; 1190 Diag(Init->getExprLoc(), 1191 diag::err_init_element_not_constant, Init->getSourceRange()); 1192 return true; 1193 case Expr::UnaryOperatorClass: { 1194 const UnaryOperator *Exp = cast<UnaryOperator>(Init); 1195 1196 switch (Exp->getOpcode()) { 1197 // Address, indirect, pre/post inc/dec, etc are not valid constant exprs. 1198 // See C99 6.6p3. 1199 default: 1200 Diag(Init->getExprLoc(), 1201 diag::err_init_element_not_constant, Init->getSourceRange()); 1202 return true; 1203 case UnaryOperator::SizeOf: 1204 case UnaryOperator::AlignOf: 1205 case UnaryOperator::OffsetOf: 1206 // sizeof(E) is a constantexpr if and only if E is not evaluted. 1207 // See C99 6.5.3.4p2 and 6.6p3. 1208 if (Exp->getSubExpr()->getType()->isConstantSizeType()) 1209 return false; 1210 Diag(Init->getExprLoc(), 1211 diag::err_init_element_not_constant, Init->getSourceRange()); 1212 return true; 1213 case UnaryOperator::Extension: 1214 case UnaryOperator::LNot: 1215 case UnaryOperator::Plus: 1216 case UnaryOperator::Minus: 1217 case UnaryOperator::Not: 1218 return CheckArithmeticConstantExpression(Exp->getSubExpr()); 1219 } 1220 } 1221 case Expr::SizeOfAlignOfTypeExprClass: { 1222 const SizeOfAlignOfTypeExpr *Exp = cast<SizeOfAlignOfTypeExpr>(Init); 1223 // Special check for void types, which are allowed as an extension 1224 if (Exp->getArgumentType()->isVoidType()) 1225 return false; 1226 // alignof always evaluates to a constant. 1227 // FIXME: is sizeof(int[3.0]) a constant expression? 1228 if (Exp->isSizeOf() && !Exp->getArgumentType()->isConstantSizeType()) { 1229 Diag(Init->getExprLoc(), 1230 diag::err_init_element_not_constant, Init->getSourceRange()); 1231 return true; 1232 } 1233 return false; 1234 } 1235 case Expr::BinaryOperatorClass: { 1236 const BinaryOperator *Exp = cast<BinaryOperator>(Init); 1237 1238 if (Exp->getLHS()->getType()->isArithmeticType() && 1239 Exp->getRHS()->getType()->isArithmeticType()) { 1240 return CheckArithmeticConstantExpression(Exp->getLHS()) || 1241 CheckArithmeticConstantExpression(Exp->getRHS()); 1242 } 1243 1244 Diag(Init->getExprLoc(), 1245 diag::err_init_element_not_constant, Init->getSourceRange()); 1246 return true; 1247 } 1248 case Expr::ImplicitCastExprClass: 1249 case Expr::CastExprClass: { 1250 const Expr *SubExpr; 1251 if (const CastExpr *C = dyn_cast<CastExpr>(Init)) { 1252 SubExpr = C->getSubExpr(); 1253 } else { 1254 SubExpr = cast<ImplicitCastExpr>(Init)->getSubExpr(); 1255 } 1256 1257 if (SubExpr->getType()->isArithmeticType()) 1258 return CheckArithmeticConstantExpression(SubExpr); 1259 1260 Diag(Init->getExprLoc(), 1261 diag::err_init_element_not_constant, Init->getSourceRange()); 1262 return true; 1263 } 1264 case Expr::ConditionalOperatorClass: { 1265 const ConditionalOperator *Exp = cast<ConditionalOperator>(Init); 1266 if (CheckArithmeticConstantExpression(Exp->getCond())) 1267 return true; 1268 if (Exp->getLHS() && 1269 CheckArithmeticConstantExpression(Exp->getLHS())) 1270 return true; 1271 return CheckArithmeticConstantExpression(Exp->getRHS()); 1272 } 1273 } 1274} 1275 1276bool Sema::CheckForConstantInitializer(Expr *Init, QualType DclT) { 1277 // Look through CXXDefaultArgExprs; they have no meaning in this context. 1278 if (CXXDefaultArgExpr* DAE = dyn_cast<CXXDefaultArgExpr>(Init)) 1279 return CheckForConstantInitializer(DAE->getExpr(), DclT); 1280 1281 if (Init->getType()->isReferenceType()) { 1282 // FIXME: Work out how the heck reference types work 1283 return false; 1284#if 0 1285 // A reference is constant if the address of the expression 1286 // is constant 1287 // We look through initlists here to simplify 1288 // CheckAddressConstantExpressionLValue. 1289 if (InitListExpr *Exp = dyn_cast<InitListExpr>(Init)) { 1290 assert(Exp->getNumInits() > 0 && 1291 "Refernce initializer cannot be empty"); 1292 Init = Exp->getInit(0); 1293 } 1294 return CheckAddressConstantExpressionLValue(Init); 1295#endif 1296 } 1297 1298 if (InitListExpr *Exp = dyn_cast<InitListExpr>(Init)) { 1299 unsigned numInits = Exp->getNumInits(); 1300 for (unsigned i = 0; i < numInits; i++) { 1301 // FIXME: Need to get the type of the declaration for C++, 1302 // because it could be a reference? 1303 if (CheckForConstantInitializer(Exp->getInit(i), 1304 Exp->getInit(i)->getType())) 1305 return true; 1306 } 1307 return false; 1308 } 1309 1310 if (Init->isNullPointerConstant(Context)) 1311 return false; 1312 if (Init->getType()->isArithmeticType()) { 1313 // Special check for pointer cast to int; we allow 1314 // an address constant cast to an integer if the integer 1315 // is of an appropriate width (this sort of code is apparently used 1316 // in some places). 1317 // FIXME: Add pedwarn? 1318 Expr* SubE = 0; 1319 if (ImplicitCastExpr* ICE = dyn_cast<ImplicitCastExpr>(Init)) 1320 SubE = ICE->getSubExpr(); 1321 else if (CastExpr* CE = dyn_cast<CastExpr>(Init)) 1322 SubE = CE->getSubExpr(); 1323 if (SubE && (SubE->getType()->isPointerType() || 1324 SubE->getType()->isArrayType() || 1325 SubE->getType()->isFunctionType())) { 1326 unsigned IntWidth = Context.getTypeSize(Init->getType()); 1327 unsigned PointerWidth = Context.getTypeSize(Context.VoidPtrTy); 1328 if (IntWidth >= PointerWidth) 1329 return CheckAddressConstantExpression(Init); 1330 } 1331 1332 return CheckArithmeticConstantExpression(Init); 1333 } 1334 1335 if (Init->getType()->isPointerType()) 1336 return CheckAddressConstantExpression(Init); 1337 1338 if (Init->getType()->isArrayType()) 1339 return false; 1340 1341 Diag(Init->getExprLoc(), diag::err_init_element_not_constant, 1342 Init->getSourceRange()); 1343 return true; 1344} 1345 1346void Sema::AddInitializerToDecl(DeclTy *dcl, ExprTy *init) { 1347 Decl *RealDecl = static_cast<Decl *>(dcl); 1348 Expr *Init = static_cast<Expr *>(init); 1349 assert(Init && "missing initializer"); 1350 1351 // If there is no declaration, there was an error parsing it. Just ignore 1352 // the initializer. 1353 if (RealDecl == 0) { 1354 delete Init; 1355 return; 1356 } 1357 1358 VarDecl *VDecl = dyn_cast<VarDecl>(RealDecl); 1359 if (!VDecl) { 1360 Diag(dyn_cast<ScopedDecl>(RealDecl)->getLocation(), 1361 diag::err_illegal_initializer); 1362 RealDecl->setInvalidDecl(); 1363 return; 1364 } 1365 // Get the decls type and save a reference for later, since 1366 // CheckInitializerTypes may change it. 1367 QualType DclT = VDecl->getType(), SavT = DclT; 1368 if (VDecl->isBlockVarDecl()) { 1369 VarDecl::StorageClass SC = VDecl->getStorageClass(); 1370 if (SC == VarDecl::Extern) { // C99 6.7.8p5 1371 Diag(VDecl->getLocation(), diag::err_block_extern_cant_init); 1372 VDecl->setInvalidDecl(); 1373 } else if (!VDecl->isInvalidDecl()) { 1374 if (CheckInitializerTypes(Init, DclT)) 1375 VDecl->setInvalidDecl(); 1376 if (SC == VarDecl::Static) // C99 6.7.8p4. 1377 CheckForConstantInitializer(Init, DclT); 1378 } 1379 } else if (VDecl->isFileVarDecl()) { 1380 if (VDecl->getStorageClass() == VarDecl::Extern) 1381 Diag(VDecl->getLocation(), diag::warn_extern_init); 1382 if (!VDecl->isInvalidDecl()) 1383 if (CheckInitializerTypes(Init, DclT)) 1384 VDecl->setInvalidDecl(); 1385 1386 // C99 6.7.8p4. All file scoped initializers need to be constant. 1387 CheckForConstantInitializer(Init, DclT); 1388 } 1389 // If the type changed, it means we had an incomplete type that was 1390 // completed by the initializer. For example: 1391 // int ary[] = { 1, 3, 5 }; 1392 // "ary" transitions from a VariableArrayType to a ConstantArrayType. 1393 if (!VDecl->isInvalidDecl() && (DclT != SavT)) { 1394 VDecl->setType(DclT); 1395 Init->setType(DclT); 1396 } 1397 1398 // Attach the initializer to the decl. 1399 VDecl->setInit(Init); 1400 return; 1401} 1402 1403/// The declarators are chained together backwards, reverse the list. 1404Sema::DeclTy *Sema::FinalizeDeclaratorGroup(Scope *S, DeclTy *group) { 1405 // Often we have single declarators, handle them quickly. 1406 Decl *GroupDecl = static_cast<Decl*>(group); 1407 if (GroupDecl == 0) 1408 return 0; 1409 1410 ScopedDecl *Group = dyn_cast<ScopedDecl>(GroupDecl); 1411 ScopedDecl *NewGroup = 0; 1412 if (Group->getNextDeclarator() == 0) 1413 NewGroup = Group; 1414 else { // reverse the list. 1415 while (Group) { 1416 ScopedDecl *Next = Group->getNextDeclarator(); 1417 Group->setNextDeclarator(NewGroup); 1418 NewGroup = Group; 1419 Group = Next; 1420 } 1421 } 1422 // Perform semantic analysis that depends on having fully processed both 1423 // the declarator and initializer. 1424 for (ScopedDecl *ID = NewGroup; ID; ID = ID->getNextDeclarator()) { 1425 VarDecl *IDecl = dyn_cast<VarDecl>(ID); 1426 if (!IDecl) 1427 continue; 1428 QualType T = IDecl->getType(); 1429 1430 // C99 6.7.5.2p2: If an identifier is declared to be an object with 1431 // static storage duration, it shall not have a variable length array. 1432 if ((IDecl->isFileVarDecl() || IDecl->isBlockVarDecl()) && 1433 IDecl->getStorageClass() == VarDecl::Static) { 1434 if (T->getAsVariableArrayType()) { 1435 Diag(IDecl->getLocation(), diag::err_typecheck_illegal_vla); 1436 IDecl->setInvalidDecl(); 1437 } 1438 } 1439 // Block scope. C99 6.7p7: If an identifier for an object is declared with 1440 // no linkage (C99 6.2.2p6), the type for the object shall be complete... 1441 if (IDecl->isBlockVarDecl() && 1442 IDecl->getStorageClass() != VarDecl::Extern) { 1443 if (T->isIncompleteType() && !IDecl->isInvalidDecl()) { 1444 Diag(IDecl->getLocation(), diag::err_typecheck_decl_incomplete_type, 1445 T.getAsString()); 1446 IDecl->setInvalidDecl(); 1447 } 1448 } 1449 // File scope. C99 6.9.2p2: A declaration of an identifier for and 1450 // object that has file scope without an initializer, and without a 1451 // storage-class specifier or with the storage-class specifier "static", 1452 // constitutes a tentative definition. Note: A tentative definition with 1453 // external linkage is valid (C99 6.2.2p5). 1454 if (IDecl && !IDecl->getInit() && 1455 (IDecl->getStorageClass() == VarDecl::Static || 1456 IDecl->getStorageClass() == VarDecl::None)) { 1457 if (T->isIncompleteArrayType()) { 1458 // C99 6.9.2 (p2, p5): Implicit initialization causes an incomplete 1459 // array to be completed. Don't issue a diagnostic. 1460 } else if (T->isIncompleteType() && !IDecl->isInvalidDecl()) { 1461 // C99 6.9.2p3: If the declaration of an identifier for an object is 1462 // a tentative definition and has internal linkage (C99 6.2.2p3), the 1463 // declared type shall not be an incomplete type. 1464 Diag(IDecl->getLocation(), diag::err_typecheck_decl_incomplete_type, 1465 T.getAsString()); 1466 IDecl->setInvalidDecl(); 1467 } 1468 } 1469 } 1470 return NewGroup; 1471} 1472 1473/// ActOnParamDeclarator - Called from Parser::ParseFunctionDeclarator() 1474/// to introduce parameters into function prototype scope. 1475Sema::DeclTy * 1476Sema::ActOnParamDeclarator(Scope *S, Declarator &D) { 1477 DeclSpec &DS = D.getDeclSpec(); 1478 1479 // Verify C99 6.7.5.3p2: The only SCS allowed is 'register'. 1480 if (DS.getStorageClassSpec() != DeclSpec::SCS_unspecified && 1481 DS.getStorageClassSpec() != DeclSpec::SCS_register) { 1482 Diag(DS.getStorageClassSpecLoc(), 1483 diag::err_invalid_storage_class_in_func_decl); 1484 DS.ClearStorageClassSpecs(); 1485 } 1486 if (DS.isThreadSpecified()) { 1487 Diag(DS.getThreadSpecLoc(), 1488 diag::err_invalid_storage_class_in_func_decl); 1489 DS.ClearStorageClassSpecs(); 1490 } 1491 1492 // Check that there are no default arguments inside the type of this 1493 // parameter (C++ only). 1494 if (getLangOptions().CPlusPlus) 1495 CheckExtraCXXDefaultArguments(D); 1496 1497 // In this context, we *do not* check D.getInvalidType(). If the declarator 1498 // type was invalid, GetTypeForDeclarator() still returns a "valid" type, 1499 // though it will not reflect the user specified type. 1500 QualType parmDeclType = GetTypeForDeclarator(D, S); 1501 1502 assert(!parmDeclType.isNull() && "GetTypeForDeclarator() returned null type"); 1503 1504 // TODO: CHECK FOR CONFLICTS, multiple decls with same name in one scope. 1505 // Can this happen for params? We already checked that they don't conflict 1506 // among each other. Here they can only shadow globals, which is ok. 1507 IdentifierInfo *II = D.getIdentifier(); 1508 if (Decl *PrevDecl = LookupDecl(II, Decl::IDNS_Ordinary, S)) { 1509 if (S->isDeclScope(PrevDecl)) { 1510 Diag(D.getIdentifierLoc(), diag::err_param_redefinition, 1511 dyn_cast<NamedDecl>(PrevDecl)->getName()); 1512 1513 // Recover by removing the name 1514 II = 0; 1515 D.SetIdentifier(0, D.getIdentifierLoc()); 1516 } 1517 } 1518 1519 // Perform the default function/array conversion (C99 6.7.5.3p[7,8]). 1520 // Doing the promotion here has a win and a loss. The win is the type for 1521 // both Decl's and DeclRefExpr's will match (a convenient invariant for the 1522 // code generator). The loss is the orginal type isn't preserved. For example: 1523 // 1524 // void func(int parmvardecl[5]) { // convert "int [5]" to "int *" 1525 // int blockvardecl[5]; 1526 // sizeof(parmvardecl); // size == 4 1527 // sizeof(blockvardecl); // size == 20 1528 // } 1529 // 1530 // For expressions, all implicit conversions are captured using the 1531 // ImplicitCastExpr AST node (we have no such mechanism for Decl's). 1532 // 1533 // FIXME: If a source translation tool needs to see the original type, then 1534 // we need to consider storing both types (in ParmVarDecl)... 1535 // 1536 if (parmDeclType->isArrayType()) { 1537 // int x[restrict 4] -> int *restrict 1538 parmDeclType = Context.getArrayDecayedType(parmDeclType); 1539 } else if (parmDeclType->isFunctionType()) 1540 parmDeclType = Context.getPointerType(parmDeclType); 1541 1542 ParmVarDecl *New = ParmVarDecl::Create(Context, CurContext, 1543 D.getIdentifierLoc(), II, 1544 parmDeclType, VarDecl::None, 1545 0, 0); 1546 1547 if (D.getInvalidType()) 1548 New->setInvalidDecl(); 1549 1550 if (II) 1551 PushOnScopeChains(New, S); 1552 1553 HandleDeclAttributes(New, D.getDeclSpec().getAttributes(), 1554 D.getAttributes()); 1555 return New; 1556 1557} 1558 1559Sema::DeclTy *Sema::ActOnStartOfFunctionDef(Scope *FnBodyScope, Declarator &D) { 1560 assert(CurFunctionDecl == 0 && "Function parsing confused"); 1561 assert(D.getTypeObject(0).Kind == DeclaratorChunk::Function && 1562 "Not a function declarator!"); 1563 DeclaratorChunk::FunctionTypeInfo &FTI = D.getTypeObject(0).Fun; 1564 1565 // Verify 6.9.1p6: 'every identifier in the identifier list shall be declared' 1566 // for a K&R function. 1567 if (!FTI.hasPrototype) { 1568 for (unsigned i = 0, e = FTI.NumArgs; i != e; ++i) { 1569 if (FTI.ArgInfo[i].Param == 0) { 1570 Diag(FTI.ArgInfo[i].IdentLoc, diag::ext_param_not_declared, 1571 FTI.ArgInfo[i].Ident->getName()); 1572 // Implicitly declare the argument as type 'int' for lack of a better 1573 // type. 1574 DeclSpec DS; 1575 const char* PrevSpec; // unused 1576 DS.SetTypeSpecType(DeclSpec::TST_int, FTI.ArgInfo[i].IdentLoc, 1577 PrevSpec); 1578 Declarator ParamD(DS, Declarator::KNRTypeListContext); 1579 ParamD.SetIdentifier(FTI.ArgInfo[i].Ident, FTI.ArgInfo[i].IdentLoc); 1580 FTI.ArgInfo[i].Param = ActOnParamDeclarator(FnBodyScope, ParamD); 1581 } 1582 } 1583 1584 // Since this is a function definition, act as though we have information 1585 // about the arguments. 1586 if (FTI.NumArgs) 1587 FTI.hasPrototype = true; 1588 } else { 1589 // FIXME: Diagnose arguments without names in C. 1590 } 1591 1592 Scope *GlobalScope = FnBodyScope->getParent(); 1593 1594 // See if this is a redefinition. 1595 Decl *PrevDcl = LookupDecl(D.getIdentifier(), Decl::IDNS_Ordinary, 1596 GlobalScope); 1597 if (PrevDcl && IdResolver.isDeclInScope(PrevDcl, CurContext)) { 1598 if (FunctionDecl *FD = dyn_cast<FunctionDecl>(PrevDcl)) { 1599 const FunctionDecl *Definition; 1600 if (FD->getBody(Definition)) { 1601 Diag(D.getIdentifierLoc(), diag::err_redefinition, 1602 D.getIdentifier()->getName()); 1603 Diag(Definition->getLocation(), diag::err_previous_definition); 1604 } 1605 } 1606 } 1607 Decl *decl = static_cast<Decl*>(ActOnDeclarator(GlobalScope, D, 0)); 1608 FunctionDecl *FD = cast<FunctionDecl>(decl); 1609 CurFunctionDecl = FD; 1610 PushDeclContext(FD); 1611 1612 // Check the validity of our function parameters 1613 CheckParmsForFunctionDef(FD); 1614 1615 // Introduce our parameters into the function scope 1616 for (unsigned p = 0, NumParams = FD->getNumParams(); p < NumParams; ++p) { 1617 ParmVarDecl *Param = FD->getParamDecl(p); 1618 // If this has an identifier, add it to the scope stack. 1619 if (Param->getIdentifier()) 1620 PushOnScopeChains(Param, FnBodyScope); 1621 } 1622 1623 return FD; 1624} 1625 1626Sema::DeclTy *Sema::ActOnFinishFunctionBody(DeclTy *D, StmtTy *Body) { 1627 Decl *dcl = static_cast<Decl *>(D); 1628 if (FunctionDecl *FD = dyn_cast<FunctionDecl>(dcl)) { 1629 FD->setBody((Stmt*)Body); 1630 assert(FD == CurFunctionDecl && "Function parsing confused"); 1631 CurFunctionDecl = 0; 1632 } else if (ObjCMethodDecl *MD = dyn_cast<ObjCMethodDecl>(dcl)) { 1633 MD->setBody((Stmt*)Body); 1634 CurMethodDecl = 0; 1635 } 1636 PopDeclContext(); 1637 // Verify and clean out per-function state. 1638 1639 // Check goto/label use. 1640 for (llvm::DenseMap<IdentifierInfo*, LabelStmt*>::iterator 1641 I = LabelMap.begin(), E = LabelMap.end(); I != E; ++I) { 1642 // Verify that we have no forward references left. If so, there was a goto 1643 // or address of a label taken, but no definition of it. Label fwd 1644 // definitions are indicated with a null substmt. 1645 if (I->second->getSubStmt() == 0) { 1646 LabelStmt *L = I->second; 1647 // Emit error. 1648 Diag(L->getIdentLoc(), diag::err_undeclared_label_use, L->getName()); 1649 1650 // At this point, we have gotos that use the bogus label. Stitch it into 1651 // the function body so that they aren't leaked and that the AST is well 1652 // formed. 1653 if (Body) { 1654 L->setSubStmt(new NullStmt(L->getIdentLoc())); 1655 cast<CompoundStmt>((Stmt*)Body)->push_back(L); 1656 } else { 1657 // The whole function wasn't parsed correctly, just delete this. 1658 delete L; 1659 } 1660 } 1661 } 1662 LabelMap.clear(); 1663 1664 return D; 1665} 1666 1667/// ImplicitlyDefineFunction - An undeclared identifier was used in a function 1668/// call, forming a call to an implicitly defined function (per C99 6.5.1p2). 1669ScopedDecl *Sema::ImplicitlyDefineFunction(SourceLocation Loc, 1670 IdentifierInfo &II, Scope *S) { 1671 // Extension in C99. Legal in C90, but warn about it. 1672 if (getLangOptions().C99) 1673 Diag(Loc, diag::ext_implicit_function_decl, II.getName()); 1674 else 1675 Diag(Loc, diag::warn_implicit_function_decl, II.getName()); 1676 1677 // FIXME: handle stuff like: 1678 // void foo() { extern float X(); } 1679 // void bar() { X(); } <-- implicit decl for X in another scope. 1680 1681 // Set a Declarator for the implicit definition: int foo(); 1682 const char *Dummy; 1683 DeclSpec DS; 1684 bool Error = DS.SetTypeSpecType(DeclSpec::TST_int, Loc, Dummy); 1685 Error = Error; // Silence warning. 1686 assert(!Error && "Error setting up implicit decl!"); 1687 Declarator D(DS, Declarator::BlockContext); 1688 D.AddTypeInfo(DeclaratorChunk::getFunction(false, false, 0, 0, Loc)); 1689 D.SetIdentifier(&II, Loc); 1690 1691 // Insert this function into translation-unit scope. 1692 1693 DeclContext *PrevDC = CurContext; 1694 CurContext = Context.getTranslationUnitDecl(); 1695 1696 FunctionDecl *FD = 1697 dyn_cast<FunctionDecl>(static_cast<Decl*>(ActOnDeclarator(TUScope, D, 0))); 1698 FD->setImplicit(); 1699 1700 CurContext = PrevDC; 1701 1702 return FD; 1703} 1704 1705 1706TypedefDecl *Sema::ParseTypedefDecl(Scope *S, Declarator &D, QualType T, 1707 ScopedDecl *LastDeclarator) { 1708 assert(D.getIdentifier() && "Wrong callback for declspec without declarator"); 1709 assert(!T.isNull() && "GetTypeForDeclarator() returned null type"); 1710 1711 // Scope manipulation handled by caller. 1712 TypedefDecl *NewTD = TypedefDecl::Create(Context, CurContext, 1713 D.getIdentifierLoc(), 1714 D.getIdentifier(), 1715 T, LastDeclarator); 1716 if (D.getInvalidType()) 1717 NewTD->setInvalidDecl(); 1718 return NewTD; 1719} 1720 1721/// ActOnTag - This is invoked when we see 'struct foo' or 'struct {'. In the 1722/// former case, Name will be non-null. In the later case, Name will be null. 1723/// TagType indicates what kind of tag this is. TK indicates whether this is a 1724/// reference/declaration/definition of a tag. 1725Sema::DeclTy *Sema::ActOnTag(Scope *S, unsigned TagType, TagKind TK, 1726 SourceLocation KWLoc, IdentifierInfo *Name, 1727 SourceLocation NameLoc, AttributeList *Attr) { 1728 // If this is a use of an existing tag, it must have a name. 1729 assert((Name != 0 || TK == TK_Definition) && 1730 "Nameless record must be a definition!"); 1731 1732 Decl::Kind Kind; 1733 switch (TagType) { 1734 default: assert(0 && "Unknown tag type!"); 1735 case DeclSpec::TST_struct: Kind = Decl::Struct; break; 1736 case DeclSpec::TST_union: Kind = Decl::Union; break; 1737 case DeclSpec::TST_class: Kind = Decl::Class; break; 1738 case DeclSpec::TST_enum: Kind = Decl::Enum; break; 1739 } 1740 1741 // If this is a named struct, check to see if there was a previous forward 1742 // declaration or definition. 1743 // Use ScopedDecl instead of TagDecl, because a NamespaceDecl may come up. 1744 if (ScopedDecl *PrevDecl = 1745 dyn_cast_or_null<ScopedDecl>(LookupDecl(Name, Decl::IDNS_Tag, S))) { 1746 1747 assert((isa<TagDecl>(PrevDecl) || isa<NamespaceDecl>(PrevDecl)) && 1748 "unexpected Decl type"); 1749 if (TagDecl *PrevTagDecl = dyn_cast<TagDecl>(PrevDecl)) { 1750 // If this is a use of a previous tag, or if the tag is already declared in 1751 // the same scope (so that the definition/declaration completes or 1752 // rementions the tag), reuse the decl. 1753 if (TK == TK_Reference || 1754 IdResolver.isDeclInScope(PrevDecl, CurContext, S)) { 1755 // Make sure that this wasn't declared as an enum and now used as a struct 1756 // or something similar. 1757 if (PrevDecl->getKind() != Kind) { 1758 Diag(KWLoc, diag::err_use_with_wrong_tag, Name->getName()); 1759 Diag(PrevDecl->getLocation(), diag::err_previous_use); 1760 } 1761 1762 // If this is a use or a forward declaration, we're good. 1763 if (TK != TK_Definition) 1764 return PrevDecl; 1765 1766 // Diagnose attempts to redefine a tag. 1767 if (PrevTagDecl->isDefinition()) { 1768 Diag(NameLoc, diag::err_redefinition, Name->getName()); 1769 Diag(PrevDecl->getLocation(), diag::err_previous_definition); 1770 // If this is a redefinition, recover by making this struct be 1771 // anonymous, which will make any later references get the previous 1772 // definition. 1773 Name = 0; 1774 } else { 1775 // Okay, this is definition of a previously declared or referenced tag. 1776 // Move the location of the decl to be the definition site. 1777 PrevDecl->setLocation(NameLoc); 1778 return PrevDecl; 1779 } 1780 } 1781 // If we get here, this is a definition of a new struct type in a nested 1782 // scope, e.g. "struct foo; void bar() { struct foo; }", just create a new 1783 // type. 1784 } else { 1785 // The tag name clashes with a namespace name, issue an error and recover 1786 // by making this tag be anonymous. 1787 Diag(NameLoc, diag::err_redefinition_different_kind, Name->getName()); 1788 Diag(PrevDecl->getLocation(), diag::err_previous_definition); 1789 Name = 0; 1790 } 1791 } 1792 1793 // If there is an identifier, use the location of the identifier as the 1794 // location of the decl, otherwise use the location of the struct/union 1795 // keyword. 1796 SourceLocation Loc = NameLoc.isValid() ? NameLoc : KWLoc; 1797 1798 // Otherwise, if this is the first time we've seen this tag, create the decl. 1799 TagDecl *New; 1800 switch (Kind) { 1801 default: assert(0 && "Unknown tag kind!"); 1802 case Decl::Enum: 1803 // FIXME: Tag decls should be chained to any simultaneous vardecls, e.g.: 1804 // enum X { A, B, C } D; D should chain to X. 1805 New = EnumDecl::Create(Context, CurContext, Loc, Name, 0); 1806 // If this is an undefined enum, warn. 1807 if (TK != TK_Definition) Diag(Loc, diag::ext_forward_ref_enum); 1808 break; 1809 case Decl::Union: 1810 case Decl::Struct: 1811 case Decl::Class: 1812 // FIXME: Tag decls should be chained to any simultaneous vardecls, e.g.: 1813 // struct X { int A; } D; D should chain to X. 1814 New = RecordDecl::Create(Context, Kind, CurContext, Loc, Name, 0); 1815 break; 1816 } 1817 1818 // If this has an identifier, add it to the scope stack. 1819 if (Name) { 1820 // The scope passed in may not be a decl scope. Zip up the scope tree until 1821 // we find one that is. 1822 while ((S->getFlags() & Scope::DeclScope) == 0) 1823 S = S->getParent(); 1824 1825 // Add it to the decl chain. 1826 PushOnScopeChains(New, S); 1827 } 1828 1829 HandleDeclAttributes(New, Attr, 0); 1830 return New; 1831} 1832 1833/// ActOnField - Each field of a struct/union/class is passed into this in order 1834/// to create a FieldDecl object for it. 1835Sema::DeclTy *Sema::ActOnField(Scope *S, 1836 SourceLocation DeclStart, 1837 Declarator &D, ExprTy *BitfieldWidth) { 1838 IdentifierInfo *II = D.getIdentifier(); 1839 Expr *BitWidth = (Expr*)BitfieldWidth; 1840 SourceLocation Loc = DeclStart; 1841 if (II) Loc = D.getIdentifierLoc(); 1842 1843 // FIXME: Unnamed fields can be handled in various different ways, for 1844 // example, unnamed unions inject all members into the struct namespace! 1845 1846 1847 if (BitWidth) { 1848 // TODO: Validate. 1849 //printf("WARNING: BITFIELDS IGNORED!\n"); 1850 1851 // 6.7.2.1p3 1852 // 6.7.2.1p4 1853 1854 } else { 1855 // Not a bitfield. 1856 1857 // validate II. 1858 1859 } 1860 1861 QualType T = GetTypeForDeclarator(D, S); 1862 assert(!T.isNull() && "GetTypeForDeclarator() returned null type"); 1863 bool InvalidDecl = false; 1864 1865 // C99 6.7.2.1p8: A member of a structure or union may have any type other 1866 // than a variably modified type. 1867 if (T->isVariablyModifiedType()) { 1868 // FIXME: This diagnostic needs work 1869 Diag(Loc, diag::err_typecheck_illegal_vla, Loc); 1870 InvalidDecl = true; 1871 } 1872 // FIXME: Chain fielddecls together. 1873 FieldDecl *NewFD = FieldDecl::Create(Context, Loc, II, T, BitWidth); 1874 1875 HandleDeclAttributes(NewFD, D.getDeclSpec().getAttributes(), 1876 D.getAttributes()); 1877 1878 if (D.getInvalidType() || InvalidDecl) 1879 NewFD->setInvalidDecl(); 1880 return NewFD; 1881} 1882 1883/// TranslateIvarVisibility - Translate visibility from a token ID to an 1884/// AST enum value. 1885static ObjCIvarDecl::AccessControl 1886TranslateIvarVisibility(tok::ObjCKeywordKind ivarVisibility) { 1887 switch (ivarVisibility) { 1888 case tok::objc_private: return ObjCIvarDecl::Private; 1889 case tok::objc_public: return ObjCIvarDecl::Public; 1890 case tok::objc_protected: return ObjCIvarDecl::Protected; 1891 case tok::objc_package: return ObjCIvarDecl::Package; 1892 default: assert(false && "Unknown visitibility kind"); 1893 } 1894} 1895 1896/// ActOnIvar - Each ivar field of an objective-c class is passed into this 1897/// in order to create an IvarDecl object for it. 1898Sema::DeclTy *Sema::ActOnIvar(Scope *S, 1899 SourceLocation DeclStart, 1900 Declarator &D, ExprTy *BitfieldWidth, 1901 tok::ObjCKeywordKind Visibility) { 1902 IdentifierInfo *II = D.getIdentifier(); 1903 Expr *BitWidth = (Expr*)BitfieldWidth; 1904 SourceLocation Loc = DeclStart; 1905 if (II) Loc = D.getIdentifierLoc(); 1906 1907 // FIXME: Unnamed fields can be handled in various different ways, for 1908 // example, unnamed unions inject all members into the struct namespace! 1909 1910 1911 if (BitWidth) { 1912 // TODO: Validate. 1913 //printf("WARNING: BITFIELDS IGNORED!\n"); 1914 1915 // 6.7.2.1p3 1916 // 6.7.2.1p4 1917 1918 } else { 1919 // Not a bitfield. 1920 1921 // validate II. 1922 1923 } 1924 1925 QualType T = GetTypeForDeclarator(D, S); 1926 assert(!T.isNull() && "GetTypeForDeclarator() returned null type"); 1927 bool InvalidDecl = false; 1928 1929 // C99 6.7.2.1p8: A member of a structure or union may have any type other 1930 // than a variably modified type. 1931 if (T->isVariablyModifiedType()) { 1932 // FIXME: This diagnostic needs work 1933 Diag(Loc, diag::err_typecheck_illegal_vla, Loc); 1934 InvalidDecl = true; 1935 } 1936 1937 ObjCIvarDecl *NewID = ObjCIvarDecl::Create(Context, Loc, II, T); 1938 1939 HandleDeclAttributes(NewID, D.getDeclSpec().getAttributes(), 1940 D.getAttributes()); 1941 1942 if (D.getInvalidType() || InvalidDecl) 1943 NewID->setInvalidDecl(); 1944 // If we have visibility info, make sure the AST is set accordingly. 1945 if (Visibility != tok::objc_not_keyword) 1946 NewID->setAccessControl(TranslateIvarVisibility(Visibility)); 1947 return NewID; 1948} 1949 1950void Sema::ActOnFields(Scope* S, 1951 SourceLocation RecLoc, DeclTy *RecDecl, 1952 DeclTy **Fields, unsigned NumFields, 1953 SourceLocation LBrac, SourceLocation RBrac) { 1954 Decl *EnclosingDecl = static_cast<Decl*>(RecDecl); 1955 assert(EnclosingDecl && "missing record or interface decl"); 1956 RecordDecl *Record = dyn_cast<RecordDecl>(EnclosingDecl); 1957 1958 if (Record && Record->isDefinition()) { 1959 // Diagnose code like: 1960 // struct S { struct S {} X; }; 1961 // We discover this when we complete the outer S. Reject and ignore the 1962 // outer S. 1963 Diag(Record->getLocation(), diag::err_nested_redefinition, 1964 Record->getKindName()); 1965 Diag(RecLoc, diag::err_previous_definition); 1966 Record->setInvalidDecl(); 1967 return; 1968 } 1969 // Verify that all the fields are okay. 1970 unsigned NumNamedMembers = 0; 1971 llvm::SmallVector<FieldDecl*, 32> RecFields; 1972 llvm::SmallSet<const IdentifierInfo*, 32> FieldIDs; 1973 1974 for (unsigned i = 0; i != NumFields; ++i) { 1975 1976 FieldDecl *FD = cast_or_null<FieldDecl>(static_cast<Decl*>(Fields[i])); 1977 assert(FD && "missing field decl"); 1978 1979 // Remember all fields. 1980 RecFields.push_back(FD); 1981 1982 // Get the type for the field. 1983 Type *FDTy = FD->getType().getTypePtr(); 1984 1985 // C99 6.7.2.1p2 - A field may not be a function type. 1986 if (FDTy->isFunctionType()) { 1987 Diag(FD->getLocation(), diag::err_field_declared_as_function, 1988 FD->getName()); 1989 FD->setInvalidDecl(); 1990 EnclosingDecl->setInvalidDecl(); 1991 continue; 1992 } 1993 // C99 6.7.2.1p2 - A field may not be an incomplete type except... 1994 if (FDTy->isIncompleteType()) { 1995 if (!Record) { // Incomplete ivar type is always an error. 1996 Diag(FD->getLocation(), diag::err_field_incomplete, FD->getName()); 1997 FD->setInvalidDecl(); 1998 EnclosingDecl->setInvalidDecl(); 1999 continue; 2000 } 2001 if (i != NumFields-1 || // ... that the last member ... 2002 Record->getKind() != Decl::Struct || // ... of a structure ... 2003 !FDTy->isArrayType()) { //... may have incomplete array type. 2004 Diag(FD->getLocation(), diag::err_field_incomplete, FD->getName()); 2005 FD->setInvalidDecl(); 2006 EnclosingDecl->setInvalidDecl(); 2007 continue; 2008 } 2009 if (NumNamedMembers < 1) { //... must have more than named member ... 2010 Diag(FD->getLocation(), diag::err_flexible_array_empty_struct, 2011 FD->getName()); 2012 FD->setInvalidDecl(); 2013 EnclosingDecl->setInvalidDecl(); 2014 continue; 2015 } 2016 // Okay, we have a legal flexible array member at the end of the struct. 2017 if (Record) 2018 Record->setHasFlexibleArrayMember(true); 2019 } 2020 /// C99 6.7.2.1p2 - a struct ending in a flexible array member cannot be the 2021 /// field of another structure or the element of an array. 2022 if (const RecordType *FDTTy = FDTy->getAsRecordType()) { 2023 if (FDTTy->getDecl()->hasFlexibleArrayMember()) { 2024 // If this is a member of a union, then entire union becomes "flexible". 2025 if (Record && Record->getKind() == Decl::Union) { 2026 Record->setHasFlexibleArrayMember(true); 2027 } else { 2028 // If this is a struct/class and this is not the last element, reject 2029 // it. Note that GCC supports variable sized arrays in the middle of 2030 // structures. 2031 if (i != NumFields-1) { 2032 Diag(FD->getLocation(), diag::err_variable_sized_type_in_struct, 2033 FD->getName()); 2034 FD->setInvalidDecl(); 2035 EnclosingDecl->setInvalidDecl(); 2036 continue; 2037 } 2038 // We support flexible arrays at the end of structs in other structs 2039 // as an extension. 2040 Diag(FD->getLocation(), diag::ext_flexible_array_in_struct, 2041 FD->getName()); 2042 if (Record) 2043 Record->setHasFlexibleArrayMember(true); 2044 } 2045 } 2046 } 2047 /// A field cannot be an Objective-c object 2048 if (FDTy->isObjCInterfaceType()) { 2049 Diag(FD->getLocation(), diag::err_statically_allocated_object, 2050 FD->getName()); 2051 FD->setInvalidDecl(); 2052 EnclosingDecl->setInvalidDecl(); 2053 continue; 2054 } 2055 // Keep track of the number of named members. 2056 if (IdentifierInfo *II = FD->getIdentifier()) { 2057 // Detect duplicate member names. 2058 if (!FieldIDs.insert(II)) { 2059 Diag(FD->getLocation(), diag::err_duplicate_member, II->getName()); 2060 // Find the previous decl. 2061 SourceLocation PrevLoc; 2062 for (unsigned i = 0, e = RecFields.size(); ; ++i) { 2063 assert(i != e && "Didn't find previous def!"); 2064 if (RecFields[i]->getIdentifier() == II) { 2065 PrevLoc = RecFields[i]->getLocation(); 2066 break; 2067 } 2068 } 2069 Diag(PrevLoc, diag::err_previous_definition); 2070 FD->setInvalidDecl(); 2071 EnclosingDecl->setInvalidDecl(); 2072 continue; 2073 } 2074 ++NumNamedMembers; 2075 } 2076 } 2077 2078 // Okay, we successfully defined 'Record'. 2079 if (Record) { 2080 Record->defineBody(&RecFields[0], RecFields.size()); 2081 Consumer.HandleTagDeclDefinition(Record); 2082 } else { 2083 ObjCIvarDecl **ClsFields = reinterpret_cast<ObjCIvarDecl**>(&RecFields[0]); 2084 if (ObjCInterfaceDecl *ID = dyn_cast<ObjCInterfaceDecl>(EnclosingDecl)) 2085 ID->addInstanceVariablesToClass(ClsFields, RecFields.size(), RBrac); 2086 else if (ObjCImplementationDecl *IMPDecl = 2087 dyn_cast<ObjCImplementationDecl>(EnclosingDecl)) { 2088 assert(IMPDecl && "ActOnFields - missing ObjCImplementationDecl"); 2089 IMPDecl->ObjCAddInstanceVariablesToClassImpl(ClsFields, RecFields.size()); 2090 CheckImplementationIvars(IMPDecl, ClsFields, RecFields.size(), RBrac); 2091 } 2092 } 2093} 2094 2095Sema::DeclTy *Sema::ActOnEnumConstant(Scope *S, DeclTy *theEnumDecl, 2096 DeclTy *lastEnumConst, 2097 SourceLocation IdLoc, IdentifierInfo *Id, 2098 SourceLocation EqualLoc, ExprTy *val) { 2099 EnumDecl *TheEnumDecl = cast<EnumDecl>(static_cast<Decl*>(theEnumDecl)); 2100 EnumConstantDecl *LastEnumConst = 2101 cast_or_null<EnumConstantDecl>(static_cast<Decl*>(lastEnumConst)); 2102 Expr *Val = static_cast<Expr*>(val); 2103 2104 // The scope passed in may not be a decl scope. Zip up the scope tree until 2105 // we find one that is. 2106 while ((S->getFlags() & Scope::DeclScope) == 0) 2107 S = S->getParent(); 2108 2109 // Verify that there isn't already something declared with this name in this 2110 // scope. 2111 if (Decl *PrevDecl = LookupDecl(Id, Decl::IDNS_Ordinary, S)) { 2112 if (IdResolver.isDeclInScope(PrevDecl, CurContext, S)) { 2113 if (isa<EnumConstantDecl>(PrevDecl)) 2114 Diag(IdLoc, diag::err_redefinition_of_enumerator, Id->getName()); 2115 else 2116 Diag(IdLoc, diag::err_redefinition, Id->getName()); 2117 Diag(PrevDecl->getLocation(), diag::err_previous_definition); 2118 delete Val; 2119 return 0; 2120 } 2121 } 2122 2123 llvm::APSInt EnumVal(32); 2124 QualType EltTy; 2125 if (Val) { 2126 // Make sure to promote the operand type to int. 2127 UsualUnaryConversions(Val); 2128 2129 // C99 6.7.2.2p2: Make sure we have an integer constant expression. 2130 SourceLocation ExpLoc; 2131 if (!Val->isIntegerConstantExpr(EnumVal, Context, &ExpLoc)) { 2132 Diag(ExpLoc, diag::err_enum_value_not_integer_constant_expr, 2133 Id->getName()); 2134 delete Val; 2135 Val = 0; // Just forget about it. 2136 } else { 2137 EltTy = Val->getType(); 2138 } 2139 } 2140 2141 if (!Val) { 2142 if (LastEnumConst) { 2143 // Assign the last value + 1. 2144 EnumVal = LastEnumConst->getInitVal(); 2145 ++EnumVal; 2146 2147 // Check for overflow on increment. 2148 if (EnumVal < LastEnumConst->getInitVal()) 2149 Diag(IdLoc, diag::warn_enum_value_overflow); 2150 2151 EltTy = LastEnumConst->getType(); 2152 } else { 2153 // First value, set to zero. 2154 EltTy = Context.IntTy; 2155 EnumVal.zextOrTrunc(static_cast<uint32_t>(Context.getTypeSize(EltTy))); 2156 } 2157 } 2158 2159 EnumConstantDecl *New = 2160 EnumConstantDecl::Create(Context, TheEnumDecl, IdLoc, Id, EltTy, 2161 Val, EnumVal, 2162 LastEnumConst); 2163 2164 // Register this decl in the current scope stack. 2165 PushOnScopeChains(New, S); 2166 return New; 2167} 2168 2169void Sema::ActOnEnumBody(SourceLocation EnumLoc, DeclTy *EnumDeclX, 2170 DeclTy **Elements, unsigned NumElements) { 2171 EnumDecl *Enum = cast<EnumDecl>(static_cast<Decl*>(EnumDeclX)); 2172 assert(!Enum->isDefinition() && "Enum redefinitions can't reach here"); 2173 2174 // TODO: If the result value doesn't fit in an int, it must be a long or long 2175 // long value. ISO C does not support this, but GCC does as an extension, 2176 // emit a warning. 2177 unsigned IntWidth = Context.Target.getIntWidth(); 2178 2179 // Verify that all the values are okay, compute the size of the values, and 2180 // reverse the list. 2181 unsigned NumNegativeBits = 0; 2182 unsigned NumPositiveBits = 0; 2183 2184 // Keep track of whether all elements have type int. 2185 bool AllElementsInt = true; 2186 2187 EnumConstantDecl *EltList = 0; 2188 for (unsigned i = 0; i != NumElements; ++i) { 2189 EnumConstantDecl *ECD = 2190 cast_or_null<EnumConstantDecl>(static_cast<Decl*>(Elements[i])); 2191 if (!ECD) continue; // Already issued a diagnostic. 2192 2193 // If the enum value doesn't fit in an int, emit an extension warning. 2194 const llvm::APSInt &InitVal = ECD->getInitVal(); 2195 assert(InitVal.getBitWidth() >= IntWidth && 2196 "Should have promoted value to int"); 2197 if (InitVal.getBitWidth() > IntWidth) { 2198 llvm::APSInt V(InitVal); 2199 V.trunc(IntWidth); 2200 V.extend(InitVal.getBitWidth()); 2201 if (V != InitVal) 2202 Diag(ECD->getLocation(), diag::ext_enum_value_not_int, 2203 InitVal.toString()); 2204 } 2205 2206 // Keep track of the size of positive and negative values. 2207 if (InitVal.isUnsigned() || InitVal.isNonNegative()) 2208 NumPositiveBits = std::max(NumPositiveBits, 2209 (unsigned)InitVal.getActiveBits()); 2210 else 2211 NumNegativeBits = std::max(NumNegativeBits, 2212 (unsigned)InitVal.getMinSignedBits()); 2213 2214 // Keep track of whether every enum element has type int (very commmon). 2215 if (AllElementsInt) 2216 AllElementsInt = ECD->getType() == Context.IntTy; 2217 2218 ECD->setNextDeclarator(EltList); 2219 EltList = ECD; 2220 } 2221 2222 // Figure out the type that should be used for this enum. 2223 // FIXME: Support attribute(packed) on enums and -fshort-enums. 2224 QualType BestType; 2225 unsigned BestWidth; 2226 2227 if (NumNegativeBits) { 2228 // If there is a negative value, figure out the smallest integer type (of 2229 // int/long/longlong) that fits. 2230 if (NumNegativeBits <= IntWidth && NumPositiveBits < IntWidth) { 2231 BestType = Context.IntTy; 2232 BestWidth = IntWidth; 2233 } else { 2234 BestWidth = Context.Target.getLongWidth(); 2235 2236 if (NumNegativeBits <= BestWidth && NumPositiveBits < BestWidth) 2237 BestType = Context.LongTy; 2238 else { 2239 BestWidth = Context.Target.getLongLongWidth(); 2240 2241 if (NumNegativeBits > BestWidth || NumPositiveBits >= BestWidth) 2242 Diag(Enum->getLocation(), diag::warn_enum_too_large); 2243 BestType = Context.LongLongTy; 2244 } 2245 } 2246 } else { 2247 // If there is no negative value, figure out which of uint, ulong, ulonglong 2248 // fits. 2249 if (NumPositiveBits <= IntWidth) { 2250 BestType = Context.UnsignedIntTy; 2251 BestWidth = IntWidth; 2252 } else if (NumPositiveBits <= 2253 (BestWidth = Context.Target.getLongWidth())) { 2254 BestType = Context.UnsignedLongTy; 2255 } else { 2256 BestWidth = Context.Target.getLongLongWidth(); 2257 assert(NumPositiveBits <= BestWidth && 2258 "How could an initializer get larger than ULL?"); 2259 BestType = Context.UnsignedLongLongTy; 2260 } 2261 } 2262 2263 // Loop over all of the enumerator constants, changing their types to match 2264 // the type of the enum if needed. 2265 for (unsigned i = 0; i != NumElements; ++i) { 2266 EnumConstantDecl *ECD = 2267 cast_or_null<EnumConstantDecl>(static_cast<Decl*>(Elements[i])); 2268 if (!ECD) continue; // Already issued a diagnostic. 2269 2270 // Standard C says the enumerators have int type, but we allow, as an 2271 // extension, the enumerators to be larger than int size. If each 2272 // enumerator value fits in an int, type it as an int, otherwise type it the 2273 // same as the enumerator decl itself. This means that in "enum { X = 1U }" 2274 // that X has type 'int', not 'unsigned'. 2275 if (ECD->getType() == Context.IntTy) { 2276 // Make sure the init value is signed. 2277 llvm::APSInt IV = ECD->getInitVal(); 2278 IV.setIsSigned(true); 2279 ECD->setInitVal(IV); 2280 continue; // Already int type. 2281 } 2282 2283 // Determine whether the value fits into an int. 2284 llvm::APSInt InitVal = ECD->getInitVal(); 2285 bool FitsInInt; 2286 if (InitVal.isUnsigned() || !InitVal.isNegative()) 2287 FitsInInt = InitVal.getActiveBits() < IntWidth; 2288 else 2289 FitsInInt = InitVal.getMinSignedBits() <= IntWidth; 2290 2291 // If it fits into an integer type, force it. Otherwise force it to match 2292 // the enum decl type. 2293 QualType NewTy; 2294 unsigned NewWidth; 2295 bool NewSign; 2296 if (FitsInInt) { 2297 NewTy = Context.IntTy; 2298 NewWidth = IntWidth; 2299 NewSign = true; 2300 } else if (ECD->getType() == BestType) { 2301 // Already the right type! 2302 continue; 2303 } else { 2304 NewTy = BestType; 2305 NewWidth = BestWidth; 2306 NewSign = BestType->isSignedIntegerType(); 2307 } 2308 2309 // Adjust the APSInt value. 2310 InitVal.extOrTrunc(NewWidth); 2311 InitVal.setIsSigned(NewSign); 2312 ECD->setInitVal(InitVal); 2313 2314 // Adjust the Expr initializer and type. 2315 ECD->setInitExpr(new ImplicitCastExpr(NewTy, ECD->getInitExpr())); 2316 ECD->setType(NewTy); 2317 } 2318 2319 Enum->defineElements(EltList, BestType); 2320 Consumer.HandleTagDeclDefinition(Enum); 2321} 2322 2323Sema::DeclTy *Sema::ActOnFileScopeAsmDecl(SourceLocation Loc, 2324 ExprTy *expr) { 2325 StringLiteral *AsmString = cast<StringLiteral>((Expr*)expr); 2326 2327 return FileScopeAsmDecl::Create(Context, Loc, AsmString); 2328} 2329 2330Sema::DeclTy* Sema::ActOnLinkageSpec(SourceLocation Loc, 2331 SourceLocation LBrace, 2332 SourceLocation RBrace, 2333 const char *Lang, 2334 unsigned StrSize, 2335 DeclTy *D) { 2336 LinkageSpecDecl::LanguageIDs Language; 2337 Decl *dcl = static_cast<Decl *>(D); 2338 if (strncmp(Lang, "\"C\"", StrSize) == 0) 2339 Language = LinkageSpecDecl::lang_c; 2340 else if (strncmp(Lang, "\"C++\"", StrSize) == 0) 2341 Language = LinkageSpecDecl::lang_cxx; 2342 else { 2343 Diag(Loc, diag::err_bad_language); 2344 return 0; 2345 } 2346 2347 // FIXME: Add all the various semantics of linkage specifications 2348 return LinkageSpecDecl::Create(Context, Loc, Language, dcl); 2349} 2350 2351void Sema::HandleDeclAttribute(Decl *New, AttributeList *Attr) { 2352 2353 switch (Attr->getKind()) { 2354 case AttributeList::AT_vector_size: 2355 if (ValueDecl *vDecl = dyn_cast<ValueDecl>(New)) { 2356 QualType newType = HandleVectorTypeAttribute(vDecl->getType(), Attr); 2357 if (!newType.isNull()) // install the new vector type into the decl 2358 vDecl->setType(newType); 2359 } 2360 if (TypedefDecl *tDecl = dyn_cast<TypedefDecl>(New)) { 2361 QualType newType = HandleVectorTypeAttribute(tDecl->getUnderlyingType(), 2362 Attr); 2363 if (!newType.isNull()) // install the new vector type into the decl 2364 tDecl->setUnderlyingType(newType); 2365 } 2366 break; 2367 case AttributeList::AT_ext_vector_type: 2368 if (TypedefDecl *tDecl = dyn_cast<TypedefDecl>(New)) 2369 HandleExtVectorTypeAttribute(tDecl, Attr); 2370 else 2371 Diag(Attr->getLoc(), 2372 diag::err_typecheck_ext_vector_not_typedef); 2373 break; 2374 case AttributeList::AT_address_space: 2375 if (TypedefDecl *tDecl = dyn_cast<TypedefDecl>(New)) { 2376 QualType newType = HandleAddressSpaceTypeAttribute( 2377 tDecl->getUnderlyingType(), 2378 Attr); 2379 tDecl->setUnderlyingType(newType); 2380 } else if (ValueDecl *vDecl = dyn_cast<ValueDecl>(New)) { 2381 QualType newType = HandleAddressSpaceTypeAttribute(vDecl->getType(), 2382 Attr); 2383 // install the new addr spaced type into the decl 2384 vDecl->setType(newType); 2385 } 2386 break; 2387 case AttributeList::AT_deprecated: 2388 HandleDeprecatedAttribute(New, Attr); 2389 break; 2390 case AttributeList::AT_visibility: 2391 HandleVisibilityAttribute(New, Attr); 2392 break; 2393 case AttributeList::AT_weak: 2394 HandleWeakAttribute(New, Attr); 2395 break; 2396 case AttributeList::AT_dllimport: 2397 HandleDLLImportAttribute(New, Attr); 2398 break; 2399 case AttributeList::AT_dllexport: 2400 HandleDLLExportAttribute(New, Attr); 2401 break; 2402 case AttributeList::AT_nothrow: 2403 HandleNothrowAttribute(New, Attr); 2404 break; 2405 case AttributeList::AT_stdcall: 2406 HandleStdCallAttribute(New, Attr); 2407 break; 2408 case AttributeList::AT_fastcall: 2409 HandleFastCallAttribute(New, Attr); 2410 break; 2411 case AttributeList::AT_aligned: 2412 HandleAlignedAttribute(New, Attr); 2413 break; 2414 case AttributeList::AT_packed: 2415 HandlePackedAttribute(New, Attr); 2416 break; 2417 case AttributeList::AT_annotate: 2418 HandleAnnotateAttribute(New, Attr); 2419 break; 2420 case AttributeList::AT_noreturn: 2421 HandleNoReturnAttribute(New, Attr); 2422 break; 2423 case AttributeList::AT_format: 2424 HandleFormatAttribute(New, Attr); 2425 break; 2426 case AttributeList::AT_transparent_union: 2427 HandleTransparentUnionAttribute(New, Attr); 2428 break; 2429 default: 2430#if 0 2431 // TODO: when we have the full set of attributes, warn about unknown ones. 2432 Diag(Attr->getLoc(), diag::warn_attribute_ignored, 2433 Attr->getName()->getName()); 2434#endif 2435 break; 2436 } 2437} 2438 2439void Sema::HandleDeclAttributes(Decl *New, AttributeList *declspec_prefix, 2440 AttributeList *declarator_postfix) { 2441 while (declspec_prefix) { 2442 HandleDeclAttribute(New, declspec_prefix); 2443 declspec_prefix = declspec_prefix->getNext(); 2444 } 2445 while (declarator_postfix) { 2446 HandleDeclAttribute(New, declarator_postfix); 2447 declarator_postfix = declarator_postfix->getNext(); 2448 } 2449} 2450 2451void Sema::HandleExtVectorTypeAttribute(TypedefDecl *tDecl, 2452 AttributeList *rawAttr) { 2453 QualType curType = tDecl->getUnderlyingType(); 2454 // check the attribute arguments. 2455 if (rawAttr->getNumArgs() != 1) { 2456 Diag(rawAttr->getLoc(), diag::err_attribute_wrong_number_arguments, 2457 std::string("1")); 2458 return; 2459 } 2460 Expr *sizeExpr = static_cast<Expr *>(rawAttr->getArg(0)); 2461 llvm::APSInt vecSize(32); 2462 if (!sizeExpr->isIntegerConstantExpr(vecSize, Context)) { 2463 Diag(rawAttr->getLoc(), diag::err_attribute_argument_not_int, 2464 "ext_vector_type", sizeExpr->getSourceRange()); 2465 return; 2466 } 2467 // unlike gcc's vector_size attribute, we do not allow vectors to be defined 2468 // in conjunction with complex types (pointers, arrays, functions, etc.). 2469 Type *canonType = curType.getCanonicalType().getTypePtr(); 2470 if (!(canonType->isIntegerType() || canonType->isRealFloatingType())) { 2471 Diag(rawAttr->getLoc(), diag::err_attribute_invalid_vector_type, 2472 curType.getCanonicalType().getAsString()); 2473 return; 2474 } 2475 // unlike gcc's vector_size attribute, the size is specified as the 2476 // number of elements, not the number of bytes. 2477 unsigned vectorSize = static_cast<unsigned>(vecSize.getZExtValue()); 2478 2479 if (vectorSize == 0) { 2480 Diag(rawAttr->getLoc(), diag::err_attribute_zero_size, 2481 sizeExpr->getSourceRange()); 2482 return; 2483 } 2484 // Instantiate/Install the vector type, the number of elements is > 0. 2485 tDecl->setUnderlyingType(Context.getExtVectorType(curType, vectorSize)); 2486 // Remember this typedef decl, we will need it later for diagnostics. 2487 ExtVectorDecls.push_back(tDecl); 2488} 2489 2490QualType Sema::HandleVectorTypeAttribute(QualType curType, 2491 AttributeList *rawAttr) { 2492 // check the attribute arugments. 2493 if (rawAttr->getNumArgs() != 1) { 2494 Diag(rawAttr->getLoc(), diag::err_attribute_wrong_number_arguments, 2495 std::string("1")); 2496 return QualType(); 2497 } 2498 Expr *sizeExpr = static_cast<Expr *>(rawAttr->getArg(0)); 2499 llvm::APSInt vecSize(32); 2500 if (!sizeExpr->isIntegerConstantExpr(vecSize, Context)) { 2501 Diag(rawAttr->getLoc(), diag::err_attribute_argument_not_int, 2502 "vector_size", sizeExpr->getSourceRange()); 2503 return QualType(); 2504 } 2505 // navigate to the base type - we need to provide for vector pointers, 2506 // vector arrays, and functions returning vectors. 2507 Type *canonType = curType.getCanonicalType().getTypePtr(); 2508 2509 if (canonType->isPointerType() || canonType->isArrayType() || 2510 canonType->isFunctionType()) { 2511 assert(0 && "HandleVector(): Complex type construction unimplemented"); 2512 /* FIXME: rebuild the type from the inside out, vectorizing the inner type. 2513 do { 2514 if (PointerType *PT = dyn_cast<PointerType>(canonType)) 2515 canonType = PT->getPointeeType().getTypePtr(); 2516 else if (ArrayType *AT = dyn_cast<ArrayType>(canonType)) 2517 canonType = AT->getElementType().getTypePtr(); 2518 else if (FunctionType *FT = dyn_cast<FunctionType>(canonType)) 2519 canonType = FT->getResultType().getTypePtr(); 2520 } while (canonType->isPointerType() || canonType->isArrayType() || 2521 canonType->isFunctionType()); 2522 */ 2523 } 2524 // the base type must be integer or float. 2525 if (!(canonType->isIntegerType() || canonType->isRealFloatingType())) { 2526 Diag(rawAttr->getLoc(), diag::err_attribute_invalid_vector_type, 2527 curType.getCanonicalType().getAsString()); 2528 return QualType(); 2529 } 2530 unsigned typeSize = static_cast<unsigned>(Context.getTypeSize(curType)); 2531 // vecSize is specified in bytes - convert to bits. 2532 unsigned vectorSize = static_cast<unsigned>(vecSize.getZExtValue() * 8); 2533 2534 // the vector size needs to be an integral multiple of the type size. 2535 if (vectorSize % typeSize) { 2536 Diag(rawAttr->getLoc(), diag::err_attribute_invalid_size, 2537 sizeExpr->getSourceRange()); 2538 return QualType(); 2539 } 2540 if (vectorSize == 0) { 2541 Diag(rawAttr->getLoc(), diag::err_attribute_zero_size, 2542 sizeExpr->getSourceRange()); 2543 return QualType(); 2544 } 2545 // Instantiate the vector type, the number of elements is > 0, and not 2546 // required to be a power of 2, unlike GCC. 2547 return Context.getVectorType(curType, vectorSize/typeSize); 2548} 2549 2550void Sema::HandlePackedAttribute(Decl *d, AttributeList *rawAttr) { 2551 // check the attribute arguments. 2552 if (rawAttr->getNumArgs() > 0) { 2553 Diag(rawAttr->getLoc(), diag::err_attribute_wrong_number_arguments, 2554 std::string("0")); 2555 return; 2556 } 2557 2558 if (TagDecl *TD = dyn_cast<TagDecl>(d)) 2559 TD->addAttr(new PackedAttr); 2560 else if (FieldDecl *FD = dyn_cast<FieldDecl>(d)) { 2561 // If the alignment is less than or equal to 8 bits, the packed attribute 2562 // has no effect. 2563 if (!FD->getType()->isIncompleteType() && 2564 Context.getTypeAlign(FD->getType()) <= 8) 2565 Diag(rawAttr->getLoc(), 2566 diag::warn_attribute_ignored_for_field_of_type, 2567 rawAttr->getName()->getName(), FD->getType().getAsString()); 2568 else 2569 FD->addAttr(new PackedAttr); 2570 } else 2571 Diag(rawAttr->getLoc(), diag::warn_attribute_ignored, 2572 rawAttr->getName()->getName()); 2573} 2574 2575void Sema::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