SemaDecl.cpp revision 87f3ff0c27be71cfd0eaf4628eb64538e84ee6ce
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// FIXME: layering (ideally, Sema shouldn't be dependent on Lex API's) 28#include "clang/Lex/Preprocessor.h" 29#include "clang/Lex/HeaderSearch.h" 30#include "llvm/ADT/SmallString.h" 31#include "llvm/ADT/SmallSet.h" 32#include "llvm/ADT/DenseSet.h" 33using namespace clang; 34 35Sema::DeclTy *Sema::isTypeName(const IdentifierInfo &II, Scope *S) { 36 Decl *IIDecl = LookupDecl(&II, Decl::IDNS_Ordinary, S, false); 37 38 if (IIDecl && (isa<TypedefDecl>(IIDecl) || isa<ObjCInterfaceDecl>(IIDecl))) 39 return IIDecl; 40 return 0; 41} 42 43void Sema::PushDeclContext(DeclContext *CD) { 44 assert(CD->getParent() == CurContext && 45 "The next DeclContext should be directly contained in the current one."); 46 CurContext = CD; 47} 48 49void Sema::PopDeclContext() { 50 assert(CurContext && "DeclContext imbalance!"); 51 CurContext = CurContext->getParent(); 52} 53 54/// Add this decl to the scope shadowed decl chains. 55void Sema::PushOnScopeChains(NamedDecl *D, Scope *S) { 56 IdResolver.AddDecl(D, S); 57 S->AddDecl(D); 58} 59 60void Sema::ActOnPopScope(SourceLocation Loc, Scope *S) { 61 if (S->decl_empty()) return; 62 assert((S->getFlags() & Scope::DeclScope) &&"Scope shouldn't contain decls!"); 63 64 for (Scope::decl_iterator I = S->decl_begin(), E = S->decl_end(); 65 I != E; ++I) { 66 Decl *TmpD = static_cast<Decl*>(*I); 67 assert(TmpD && "This decl didn't get pushed??"); 68 ScopedDecl *D = dyn_cast<ScopedDecl>(TmpD); 69 assert(D && "This decl isn't a ScopedDecl?"); 70 71 IdentifierInfo *II = D->getIdentifier(); 72 if (!II) continue; 73 74 // Unlink this decl from the identifier. 75 IdResolver.RemoveDecl(D); 76 77 // This will have to be revisited for C++: there we want to nest stuff in 78 // namespace decls etc. Even for C, we might want a top-level translation 79 // unit decl or something. 80 if (!CurFunctionDecl) 81 continue; 82 83 // Chain this decl to the containing function, it now owns the memory for 84 // the decl. 85 D->setNext(CurFunctionDecl->getDeclChain()); 86 CurFunctionDecl->setDeclChain(D); 87 } 88} 89 90/// getObjCInterfaceDecl - Look up a for a class declaration in the scope. 91/// return 0 if one not found. 92ObjCInterfaceDecl *Sema::getObjCInterfaceDecl(IdentifierInfo *Id) { 93 // The third "scope" argument is 0 since we aren't enabling lazy built-in 94 // creation from this context. 95 Decl *IDecl = LookupDecl(Id, Decl::IDNS_Ordinary, 0, false); 96 97 return dyn_cast_or_null<ObjCInterfaceDecl>(IDecl); 98} 99 100/// LookupDecl - Look up the inner-most declaration in the specified 101/// namespace. 102Decl *Sema::LookupDecl(const IdentifierInfo *II, unsigned NSI, 103 Scope *S, bool enableLazyBuiltinCreation) { 104 if (II == 0) return 0; 105 Decl::IdentifierNamespace NS = (Decl::IdentifierNamespace)NSI; 106 107 // Scan up the scope chain looking for a decl that matches this identifier 108 // that is in the appropriate namespace. This search should not take long, as 109 // shadowing of names is uncommon, and deep shadowing is extremely uncommon. 110 NamedDecl *ND = IdResolver.Lookup(II, NS); 111 if (ND) return ND; 112 113 // If we didn't find a use of this identifier, and if the identifier 114 // corresponds to a compiler builtin, create the decl object for the builtin 115 // now, injecting it into translation unit scope, and return it. 116 if (NS == Decl::IDNS_Ordinary) { 117 if (enableLazyBuiltinCreation) { 118 // If this is a builtin on this (or all) targets, create the decl. 119 if (unsigned BuiltinID = II->getBuiltinID()) 120 return LazilyCreateBuiltin((IdentifierInfo *)II, BuiltinID, S); 121 } 122 if (getLangOptions().ObjC1) { 123 // @interface and @compatibility_alias introduce typedef-like names. 124 // Unlike typedef's, they can only be introduced at file-scope (and are 125 // therefore not scoped decls). They can, however, be shadowed by 126 // other names in IDNS_Ordinary. 127 ObjCInterfaceDeclsTy::iterator IDI = ObjCInterfaceDecls.find(II); 128 if (IDI != ObjCInterfaceDecls.end()) 129 return IDI->second; 130 ObjCAliasTy::iterator I = ObjCAliasDecls.find(II); 131 if (I != ObjCAliasDecls.end()) 132 return I->second->getClassInterface(); 133 } 134 } 135 return 0; 136} 137 138void Sema::InitBuiltinVaListType() 139{ 140 if (!Context.getBuiltinVaListType().isNull()) 141 return; 142 143 IdentifierInfo *VaIdent = &Context.Idents.get("__builtin_va_list"); 144 Decl *VaDecl = LookupDecl(VaIdent, Decl::IDNS_Ordinary, TUScope); 145 TypedefDecl *VaTypedef = cast<TypedefDecl>(VaDecl); 146 Context.setBuiltinVaListType(Context.getTypedefType(VaTypedef)); 147} 148 149/// LazilyCreateBuiltin - The specified Builtin-ID was first used at file scope. 150/// lazily create a decl for it. 151ScopedDecl *Sema::LazilyCreateBuiltin(IdentifierInfo *II, unsigned bid, 152 Scope *S) { 153 Builtin::ID BID = (Builtin::ID)bid; 154 155 if (BID == Builtin::BI__builtin_va_start || 156 BID == Builtin::BI__builtin_va_copy || 157 BID == Builtin::BI__builtin_va_end) 158 InitBuiltinVaListType(); 159 160 QualType R = Context.BuiltinInfo.GetBuiltinType(BID, Context); 161 FunctionDecl *New = FunctionDecl::Create(Context, CurContext, 162 SourceLocation(), II, R, 163 FunctionDecl::Extern, false, 0); 164 165 // TUScope is the translation-unit scope to insert this function into. 166 TUScope->AddDecl(New); 167 168 // Add this decl to the end of the identifier info. 169 IdResolver.AddGlobalDecl(New); 170 171 return New; 172} 173 174/// MergeTypeDefDecl - We just parsed a typedef 'New' which has the same name 175/// and scope as a previous declaration 'Old'. Figure out how to resolve this 176/// situation, merging decls or emitting diagnostics as appropriate. 177/// 178TypedefDecl *Sema::MergeTypeDefDecl(TypedefDecl *New, Decl *OldD) { 179 // Verify the old decl was also a typedef. 180 TypedefDecl *Old = dyn_cast<TypedefDecl>(OldD); 181 if (!Old) { 182 Diag(New->getLocation(), diag::err_redefinition_different_kind, 183 New->getName()); 184 Diag(OldD->getLocation(), diag::err_previous_definition); 185 return New; 186 } 187 188 // Allow multiple definitions for ObjC built-in typedefs. 189 // FIXME: Verify the underlying types are equivalent! 190 if (getLangOptions().ObjC1 && isBuiltinObjCType(New)) 191 return Old; 192 193 // Redeclaration of a type is a constraint violation (6.7.2.3p1). 194 // Apparently GCC, Intel, and Sun all silently ignore the redeclaration if 195 // *either* declaration is in a system header. The code below implements 196 // this adhoc compatibility rule. FIXME: The following code will not 197 // work properly when compiling ".i" files (containing preprocessed output). 198 SourceManager &SrcMgr = Context.getSourceManager(); 199 const FileEntry *OldDeclFile = SrcMgr.getFileEntryForLoc(Old->getLocation()); 200 const FileEntry *NewDeclFile = SrcMgr.getFileEntryForLoc(New->getLocation()); 201 HeaderSearch &HdrInfo = PP.getHeaderSearchInfo(); 202 DirectoryLookup::DirType OldDirType = HdrInfo.getFileDirFlavor(OldDeclFile); 203 DirectoryLookup::DirType NewDirType = HdrInfo.getFileDirFlavor(NewDeclFile); 204 205 // Allow reclarations in both SystemHeaderDir and ExternCSystemHeaderDir. 206 if ((OldDirType != DirectoryLookup::NormalHeaderDir || 207 NewDirType != DirectoryLookup::NormalHeaderDir) || 208 getLangOptions().Microsoft) 209 return New; 210 211 // TODO: CHECK FOR CONFLICTS, multiple decls with same name in one scope. 212 // TODO: This is totally simplistic. It should handle merging functions 213 // together etc, merging extern int X; int X; ... 214 Diag(New->getLocation(), diag::err_redefinition, New->getName()); 215 Diag(Old->getLocation(), diag::err_previous_definition); 216 return New; 217} 218 219/// DeclhasAttr - returns true if decl Declaration already has the target attribute. 220static bool DeclHasAttr(const Decl *decl, const Attr *target) { 221 for (const Attr *attr = decl->getAttrs(); attr; attr = attr->getNext()) 222 if (attr->getKind() == target->getKind()) 223 return true; 224 225 return false; 226} 227 228/// MergeAttributes - append attributes from the Old decl to the New one. 229static void MergeAttributes(Decl *New, Decl *Old) { 230 Attr *attr = const_cast<Attr*>(Old->getAttrs()), *tmp; 231 232// FIXME: fix this code to cleanup the Old attrs correctly 233 while (attr) { 234 tmp = attr; 235 attr = attr->getNext(); 236 237 if (!DeclHasAttr(New, tmp)) { 238 New->addAttr(tmp); 239 } else { 240 tmp->setNext(0); 241 delete(tmp); 242 } 243 } 244} 245 246/// MergeFunctionDecl - We just parsed a function 'New' from 247/// declarator D which has the same name and scope as a previous 248/// declaration 'Old'. Figure out how to resolve this situation, 249/// merging decls or emitting diagnostics as appropriate. 250/// 251FunctionDecl *Sema::MergeFunctionDecl(FunctionDecl *New, Decl *OldD) { 252 // Verify the old decl was also a function. 253 FunctionDecl *Old = dyn_cast<FunctionDecl>(OldD); 254 if (!Old) { 255 Diag(New->getLocation(), diag::err_redefinition_different_kind, 256 New->getName()); 257 Diag(OldD->getLocation(), diag::err_previous_definition); 258 return New; 259 } 260 261 MergeAttributes(New, Old); 262 263 QualType OldQType = Context.getCanonicalType(Old->getType()); 264 QualType NewQType = Context.getCanonicalType(New->getType()); 265 266 // C++ [dcl.fct]p3: 267 // All declarations for a function shall agree exactly in both the 268 // return type and the parameter-type-list. 269 if (getLangOptions().CPlusPlus && OldQType == NewQType) 270 return MergeCXXFunctionDecl(New, Old); 271 272 // C: Function types need to be compatible, not identical. This handles 273 // duplicate function decls like "void f(int); void f(enum X);" properly. 274 if (!getLangOptions().CPlusPlus && 275 Context.functionTypesAreCompatible(OldQType, NewQType)) { 276 return New; 277 } 278 279 // A function that has already been declared has been redeclared or defined 280 // with a different type- show appropriate diagnostic 281 diag::kind PrevDiag; 282 if (Old->getBody()) 283 PrevDiag = diag::err_previous_definition; 284 else if (Old->isImplicit()) 285 PrevDiag = diag::err_previous_implicit_declaration; 286 else 287 PrevDiag = diag::err_previous_declaration; 288 289 // TODO: CHECK FOR CONFLICTS, multiple decls with same name in one scope. 290 // TODO: This is totally simplistic. It should handle merging functions 291 // together etc, merging extern int X; int X; ... 292 Diag(New->getLocation(), diag::err_conflicting_types, New->getName()); 293 Diag(Old->getLocation(), PrevDiag); 294 return New; 295} 296 297/// equivalentArrayTypes - Used to determine whether two array types are 298/// equivalent. 299/// We need to check this explicitly as an incomplete array definition is 300/// considered a VariableArrayType, so will not match a complete array 301/// definition that would be otherwise equivalent. 302static bool areEquivalentArrayTypes(QualType NewQType, QualType OldQType) { 303 const ArrayType *NewAT = NewQType->getAsArrayType(); 304 const ArrayType *OldAT = OldQType->getAsArrayType(); 305 306 if (!NewAT || !OldAT) 307 return false; 308 309 // If either (or both) array types in incomplete we need to strip off the 310 // outer VariableArrayType. Once the outer VAT is removed the remaining 311 // types must be identical if the array types are to be considered 312 // equivalent. 313 // eg. int[][1] and int[1][1] become 314 // VAT(null, CAT(1, int)) and CAT(1, CAT(1, int)) 315 // removing the outermost VAT gives 316 // CAT(1, int) and CAT(1, int) 317 // which are equal, therefore the array types are equivalent. 318 if (NewAT->isIncompleteArrayType() || OldAT->isIncompleteArrayType()) { 319 if (NewAT->getIndexTypeQualifier() != OldAT->getIndexTypeQualifier()) 320 return false; 321 NewQType = NewAT->getElementType().getCanonicalType(); 322 OldQType = OldAT->getElementType().getCanonicalType(); 323 } 324 325 return NewQType == OldQType; 326} 327 328/// MergeVarDecl - We just parsed a variable 'New' which has the same name 329/// and scope as a previous declaration 'Old'. Figure out how to resolve this 330/// situation, merging decls or emitting diagnostics as appropriate. 331/// 332/// FIXME: Need to carefully consider tentative definition rules (C99 6.9.2p2). 333/// For example, we incorrectly complain about i1, i4 from C99 6.9.2p4. 334/// 335VarDecl *Sema::MergeVarDecl(VarDecl *New, Decl *OldD) { 336 // Verify the old decl was also a variable. 337 VarDecl *Old = dyn_cast<VarDecl>(OldD); 338 if (!Old) { 339 Diag(New->getLocation(), diag::err_redefinition_different_kind, 340 New->getName()); 341 Diag(OldD->getLocation(), diag::err_previous_definition); 342 return New; 343 } 344 345 MergeAttributes(New, Old); 346 347 // Verify the types match. 348 QualType OldCType = Context.getCanonicalType(Old->getType()); 349 QualType NewCType = Context.getCanonicalType(New->getType()); 350 if (OldCType != NewCType && !areEquivalentArrayTypes(NewCType, OldCType)) { 351 Diag(New->getLocation(), diag::err_redefinition, New->getName()); 352 Diag(Old->getLocation(), diag::err_previous_definition); 353 return New; 354 } 355 // C99 6.2.2p4: Check if we have a static decl followed by a non-static. 356 if (New->getStorageClass() == VarDecl::Static && 357 (Old->getStorageClass() == VarDecl::None || 358 Old->getStorageClass() == VarDecl::Extern)) { 359 Diag(New->getLocation(), diag::err_static_non_static, New->getName()); 360 Diag(Old->getLocation(), diag::err_previous_definition); 361 return New; 362 } 363 // C99 6.2.2p4: Check if we have a non-static decl followed by a static. 364 if (New->getStorageClass() != VarDecl::Static && 365 Old->getStorageClass() == VarDecl::Static) { 366 Diag(New->getLocation(), diag::err_non_static_static, New->getName()); 367 Diag(Old->getLocation(), diag::err_previous_definition); 368 return New; 369 } 370 // We've verified the types match, now handle "tentative" definitions. 371 FileVarDecl *OldFSDecl = dyn_cast<FileVarDecl>(Old); 372 FileVarDecl *NewFSDecl = dyn_cast<FileVarDecl>(New); 373 374 if (OldFSDecl && NewFSDecl) { 375 // Handle C "tentative" external object definitions (C99 6.9.2). 376 bool OldIsTentative = false; 377 bool NewIsTentative = false; 378 379 if (!OldFSDecl->getInit() && 380 (OldFSDecl->getStorageClass() == VarDecl::None || 381 OldFSDecl->getStorageClass() == VarDecl::Static)) 382 OldIsTentative = true; 383 384 // FIXME: this check doesn't work (since the initializer hasn't been 385 // attached yet). This check should be moved to FinalizeDeclaratorGroup. 386 // Unfortunately, by the time we get to FinializeDeclaratorGroup, we've 387 // thrown out the old decl. 388 if (!NewFSDecl->getInit() && 389 (NewFSDecl->getStorageClass() == VarDecl::None || 390 NewFSDecl->getStorageClass() == VarDecl::Static)) 391 ; // change to NewIsTentative = true; once the code is moved. 392 393 if (NewIsTentative || OldIsTentative) 394 return New; 395 } 396 if (Old->getStorageClass() != VarDecl::Extern && 397 New->getStorageClass() != VarDecl::Extern) { 398 Diag(New->getLocation(), diag::err_redefinition, New->getName()); 399 Diag(Old->getLocation(), diag::err_previous_definition); 400 } 401 return New; 402} 403 404/// CheckParmsForFunctionDef - Check that the parameters of the given 405/// function are appropriate for the definition of a function. This 406/// takes care of any checks that cannot be performed on the 407/// declaration itself, e.g., that the types of each of the function 408/// parameters are complete. 409bool Sema::CheckParmsForFunctionDef(FunctionDecl *FD) { 410 bool HasInvalidParm = false; 411 for (unsigned p = 0, NumParams = FD->getNumParams(); p < NumParams; ++p) { 412 ParmVarDecl *Param = FD->getParamDecl(p); 413 414 // C99 6.7.5.3p4: the parameters in a parameter type list in a 415 // function declarator that is part of a function definition of 416 // that function shall not have incomplete type. 417 if (Param->getType()->isIncompleteType() && 418 !Param->isInvalidDecl()) { 419 Diag(Param->getLocation(), diag::err_typecheck_decl_incomplete_type, 420 Param->getType().getAsString()); 421 Param->setInvalidDecl(); 422 HasInvalidParm = true; 423 } 424 } 425 426 return HasInvalidParm; 427} 428 429/// CreateImplicitParameter - Creates an implicit function parameter 430/// in the scope S and with the given type. This routine is used, for 431/// example, to create the implicit "self" parameter in an Objective-C 432/// method. 433ParmVarDecl * 434Sema::CreateImplicitParameter(Scope *S, IdentifierInfo *Id, 435 SourceLocation IdLoc, QualType Type) { 436 ParmVarDecl *New = ParmVarDecl::Create(Context, CurContext, IdLoc, Id, Type, 437 VarDecl::None, 0, 0); 438 if (Id) 439 PushOnScopeChains(New, S); 440 441 return New; 442} 443 444/// ParsedFreeStandingDeclSpec - This method is invoked when a declspec with 445/// no declarator (e.g. "struct foo;") is parsed. 446Sema::DeclTy *Sema::ParsedFreeStandingDeclSpec(Scope *S, DeclSpec &DS) { 447 // TODO: emit error on 'int;' or 'const enum foo;'. 448 // TODO: emit error on 'typedef int;' 449 // if (!DS.isMissingDeclaratorOk()) Diag(...); 450 451 return dyn_cast_or_null<TagDecl>(static_cast<Decl *>(DS.getTypeRep())); 452} 453 454bool Sema::CheckSingleInitializer(Expr *&Init, QualType DeclType) { 455 // Get the type before calling CheckSingleAssignmentConstraints(), since 456 // it can promote the expression. 457 QualType InitType = Init->getType(); 458 459 AssignConvertType ConvTy = CheckSingleAssignmentConstraints(DeclType, Init); 460 return DiagnoseAssignmentResult(ConvTy, Init->getLocStart(), DeclType, 461 InitType, Init, "initializing"); 462} 463 464bool Sema::CheckInitExpr(Expr *expr, InitListExpr *IList, unsigned slot, 465 QualType ElementType) { 466 Expr *savExpr = expr; // Might be promoted by CheckSingleInitializer. 467 if (CheckSingleInitializer(expr, ElementType)) 468 return true; // types weren't compatible. 469 470 if (savExpr != expr) // The type was promoted, update initializer list. 471 IList->setInit(slot, expr); 472 return false; 473} 474 475bool Sema::CheckStringLiteralInit(StringLiteral *strLiteral, QualType &DeclT) { 476 if (const IncompleteArrayType *IAT = DeclT->getAsIncompleteArrayType()) { 477 // C99 6.7.8p14. We have an array of character type with unknown size 478 // being initialized to a string literal. 479 llvm::APSInt ConstVal(32); 480 ConstVal = strLiteral->getByteLength() + 1; 481 // Return a new array type (C99 6.7.8p22). 482 DeclT = Context.getConstantArrayType(IAT->getElementType(), ConstVal, 483 ArrayType::Normal, 0); 484 } else if (const ConstantArrayType *CAT = DeclT->getAsConstantArrayType()) { 485 // C99 6.7.8p14. We have an array of character type with known size. 486 if (strLiteral->getByteLength() > (unsigned)CAT->getMaximumElements()) 487 Diag(strLiteral->getSourceRange().getBegin(), 488 diag::warn_initializer_string_for_char_array_too_long, 489 strLiteral->getSourceRange()); 490 } else { 491 assert(0 && "HandleStringLiteralInit(): Invalid array type"); 492 } 493 // Set type from "char *" to "constant array of char". 494 strLiteral->setType(DeclT); 495 // For now, we always return false (meaning success). 496 return false; 497} 498 499StringLiteral *Sema::IsStringLiteralInit(Expr *Init, QualType DeclType) { 500 const ArrayType *AT = DeclType->getAsArrayType(); 501 if (AT && AT->getElementType()->isCharType()) { 502 return dyn_cast<StringLiteral>(Init); 503 } 504 return 0; 505} 506 507// CheckInitializerListTypes - Checks the types of elements of an initializer 508// list. This function is recursive: it calls itself to initialize subelements 509// of aggregate types. Note that the topLevel parameter essentially refers to 510// whether this expression "owns" the initializer list passed in, or if this 511// initialization is taking elements out of a parent initializer. Each 512// call to this function adds zero or more to startIndex, reports any errors, 513// and returns true if it found any inconsistent types. 514bool Sema::CheckInitializerListTypes(InitListExpr*& IList, QualType &DeclType, 515 bool topLevel, unsigned& startIndex) { 516 bool hadError = false; 517 518 if (DeclType->isScalarType()) { 519 // The simplest case: initializing a single scalar 520 if (topLevel) { 521 Diag(IList->getLocStart(), diag::warn_braces_around_scalar_init, 522 IList->getSourceRange()); 523 } 524 if (startIndex < IList->getNumInits()) { 525 Expr* expr = IList->getInit(startIndex); 526 if (InitListExpr *SubInitList = dyn_cast<InitListExpr>(expr)) { 527 // FIXME: Should an error be reported here instead? 528 unsigned newIndex = 0; 529 CheckInitializerListTypes(SubInitList, DeclType, true, newIndex); 530 } else { 531 hadError |= CheckInitExpr(expr, IList, startIndex, DeclType); 532 } 533 ++startIndex; 534 } 535 // FIXME: Should an error be reported for empty initializer list + scalar? 536 } else if (DeclType->isVectorType()) { 537 if (startIndex < IList->getNumInits()) { 538 const VectorType *VT = DeclType->getAsVectorType(); 539 int maxElements = VT->getNumElements(); 540 QualType elementType = VT->getElementType(); 541 542 for (int i = 0; i < maxElements; ++i) { 543 // Don't attempt to go past the end of the init list 544 if (startIndex >= IList->getNumInits()) 545 break; 546 Expr* expr = IList->getInit(startIndex); 547 if (InitListExpr *SubInitList = dyn_cast<InitListExpr>(expr)) { 548 unsigned newIndex = 0; 549 hadError |= CheckInitializerListTypes(SubInitList, elementType, 550 true, newIndex); 551 ++startIndex; 552 } else { 553 hadError |= CheckInitializerListTypes(IList, elementType, 554 false, startIndex); 555 } 556 } 557 } 558 } else if (DeclType->isAggregateType() || DeclType->isUnionType()) { 559 if (DeclType->isStructureType() || DeclType->isUnionType()) { 560 if (startIndex < IList->getNumInits() && !topLevel && 561 Context.typesAreCompatible(IList->getInit(startIndex)->getType(), 562 DeclType)) { 563 // We found a compatible struct; per the standard, this initializes the 564 // struct. (The C standard technically says that this only applies for 565 // initializers for declarations with automatic scope; however, this 566 // construct is unambiguous anyway because a struct cannot contain 567 // a type compatible with itself. We'll output an error when we check 568 // if the initializer is constant.) 569 // FIXME: Is a call to CheckSingleInitializer required here? 570 ++startIndex; 571 } else { 572 RecordDecl* structDecl = DeclType->getAsRecordType()->getDecl(); 573 574 // If the record is invalid, some of it's members are invalid. To avoid 575 // confusion, we forgo checking the intializer for the entire record. 576 if (structDecl->isInvalidDecl()) 577 return true; 578 579 // If structDecl is a forward declaration, this loop won't do anything; 580 // That's okay, because an error should get printed out elsewhere. It 581 // might be worthwhile to skip over the rest of the initializer, though. 582 int numMembers = structDecl->getNumMembers() - 583 structDecl->hasFlexibleArrayMember(); 584 for (int i = 0; i < numMembers; i++) { 585 // Don't attempt to go past the end of the init list 586 if (startIndex >= IList->getNumInits()) 587 break; 588 FieldDecl * curField = structDecl->getMember(i); 589 if (!curField->getIdentifier()) { 590 // Don't initialize unnamed fields, e.g. "int : 20;" 591 continue; 592 } 593 QualType fieldType = curField->getType(); 594 Expr* expr = IList->getInit(startIndex); 595 if (InitListExpr *SubInitList = dyn_cast<InitListExpr>(expr)) { 596 unsigned newStart = 0; 597 hadError |= CheckInitializerListTypes(SubInitList, fieldType, 598 true, newStart); 599 ++startIndex; 600 } else { 601 hadError |= CheckInitializerListTypes(IList, fieldType, 602 false, startIndex); 603 } 604 if (DeclType->isUnionType()) 605 break; 606 } 607 // FIXME: Implement flexible array initialization GCC extension (it's a 608 // really messy extension to implement, unfortunately...the necessary 609 // information isn't actually even here!) 610 } 611 } else if (DeclType->isArrayType()) { 612 // Check for the special-case of initializing an array with a string. 613 if (startIndex < IList->getNumInits()) { 614 if (StringLiteral *lit = IsStringLiteralInit(IList->getInit(startIndex), 615 DeclType)) { 616 CheckStringLiteralInit(lit, DeclType); 617 ++startIndex; 618 if (topLevel && startIndex < IList->getNumInits()) { 619 // We have leftover initializers; warn 620 Diag(IList->getInit(startIndex)->getLocStart(), 621 diag::err_excess_initializers_in_char_array_initializer, 622 IList->getInit(startIndex)->getSourceRange()); 623 } 624 return false; 625 } 626 } 627 int maxElements; 628 if (DeclType->isIncompleteArrayType()) { 629 // FIXME: use a proper constant 630 maxElements = 0x7FFFFFFF; 631 } else if (const VariableArrayType *VAT = 632 DeclType->getAsVariableArrayType()) { 633 // Check for VLAs; in standard C it would be possible to check this 634 // earlier, but I don't know where clang accepts VLAs (gcc accepts 635 // them in all sorts of strange places). 636 Diag(VAT->getSizeExpr()->getLocStart(), 637 diag::err_variable_object_no_init, 638 VAT->getSizeExpr()->getSourceRange()); 639 hadError = true; 640 maxElements = 0x7FFFFFFF; 641 } else { 642 const ConstantArrayType *CAT = DeclType->getAsConstantArrayType(); 643 maxElements = static_cast<int>(CAT->getSize().getZExtValue()); 644 } 645 QualType elementType = DeclType->getAsArrayType()->getElementType(); 646 int numElements = 0; 647 for (int i = 0; i < maxElements; ++i, ++numElements) { 648 // Don't attempt to go past the end of the init list 649 if (startIndex >= IList->getNumInits()) 650 break; 651 Expr* expr = IList->getInit(startIndex); 652 if (InitListExpr *SubInitList = dyn_cast<InitListExpr>(expr)) { 653 unsigned newIndex = 0; 654 hadError |= CheckInitializerListTypes(SubInitList, elementType, 655 true, newIndex); 656 ++startIndex; 657 } else { 658 hadError |= CheckInitializerListTypes(IList, elementType, 659 false, startIndex); 660 } 661 } 662 if (DeclType->isIncompleteArrayType()) { 663 // If this is an incomplete array type, the actual type needs to 664 // be calculated here 665 if (numElements == 0) { 666 // Sizing an array implicitly to zero is not allowed 667 // (It could in theory be allowed, but it doesn't really matter.) 668 Diag(IList->getLocStart(), 669 diag::err_at_least_one_initializer_needed_to_size_array); 670 hadError = true; 671 } else { 672 llvm::APSInt ConstVal(32); 673 ConstVal = numElements; 674 DeclType = Context.getConstantArrayType(elementType, ConstVal, 675 ArrayType::Normal, 0); 676 } 677 } 678 } else { 679 assert(0 && "Aggregate that isn't a function or array?!"); 680 } 681 } else { 682 // In C, all types are either scalars or aggregates, but 683 // additional handling is needed here for C++ (and possibly others?). 684 assert(0 && "Unsupported initializer type"); 685 } 686 687 // If this init list is a base list, we set the type; an initializer doesn't 688 // fundamentally have a type, but this makes the ASTs a bit easier to read 689 if (topLevel) 690 IList->setType(DeclType); 691 692 if (topLevel && startIndex < IList->getNumInits()) { 693 // We have leftover initializers; warn 694 Diag(IList->getInit(startIndex)->getLocStart(), 695 diag::warn_excess_initializers, 696 IList->getInit(startIndex)->getSourceRange()); 697 } 698 return hadError; 699} 700 701bool Sema::CheckInitializerTypes(Expr *&Init, QualType &DeclType) { 702 // C99 6.7.8p3: The type of the entity to be initialized shall be an array 703 // of unknown size ("[]") or an object type that is not a variable array type. 704 if (const VariableArrayType *VAT = DeclType->getAsVariableArrayType()) 705 return Diag(VAT->getSizeExpr()->getLocStart(), 706 diag::err_variable_object_no_init, 707 VAT->getSizeExpr()->getSourceRange()); 708 709 InitListExpr *InitList = dyn_cast<InitListExpr>(Init); 710 if (!InitList) { 711 // FIXME: Handle wide strings 712 if (StringLiteral *strLiteral = IsStringLiteralInit(Init, DeclType)) 713 return CheckStringLiteralInit(strLiteral, DeclType); 714 715 if (DeclType->isArrayType()) 716 return Diag(Init->getLocStart(), 717 diag::err_array_init_list_required, 718 Init->getSourceRange()); 719 720 return CheckSingleInitializer(Init, DeclType); 721 } 722 unsigned newIndex = 0; 723 return CheckInitializerListTypes(InitList, DeclType, true, newIndex); 724} 725 726Sema::DeclTy * 727Sema::ActOnDeclarator(Scope *S, Declarator &D, DeclTy *lastDecl) { 728 ScopedDecl *LastDeclarator = dyn_cast_or_null<ScopedDecl>((Decl *)lastDecl); 729 IdentifierInfo *II = D.getIdentifier(); 730 731 // All of these full declarators require an identifier. If it doesn't have 732 // one, the ParsedFreeStandingDeclSpec action should be used. 733 if (II == 0) { 734 Diag(D.getDeclSpec().getSourceRange().getBegin(), 735 diag::err_declarator_need_ident, 736 D.getDeclSpec().getSourceRange(), D.getSourceRange()); 737 return 0; 738 } 739 740 // The scope passed in may not be a decl scope. Zip up the scope tree until 741 // we find one that is. 742 while ((S->getFlags() & Scope::DeclScope) == 0) 743 S = S->getParent(); 744 745 // See if this is a redefinition of a variable in the same scope. 746 Decl *PrevDecl = LookupDecl(II, Decl::IDNS_Ordinary, S); 747 ScopedDecl *New; 748 bool InvalidDecl = false; 749 750 QualType R = GetTypeForDeclarator(D, S); 751 assert(!R.isNull() && "GetTypeForDeclarator() returned null type"); 752 753 if (D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_typedef) { 754 TypedefDecl *NewTD = ParseTypedefDecl(S, D, R, LastDeclarator); 755 if (!NewTD) return 0; 756 757 // Handle attributes prior to checking for duplicates in MergeVarDecl 758 HandleDeclAttributes(NewTD, D.getDeclSpec().getAttributes(), 759 D.getAttributes()); 760 // Merge the decl with the existing one if appropriate. If the decl is 761 // in an outer scope, it isn't the same thing. 762 if (PrevDecl && S->isDeclScope(PrevDecl)) { 763 NewTD = MergeTypeDefDecl(NewTD, PrevDecl); 764 if (NewTD == 0) return 0; 765 } 766 New = NewTD; 767 if (S->getParent() == 0) { 768 // C99 6.7.7p2: If a typedef name specifies a variably modified type 769 // then it shall have block scope. 770 if (NewTD->getUnderlyingType()->isVariablyModifiedType()) { 771 // FIXME: Diagnostic needs to be fixed. 772 Diag(D.getIdentifierLoc(), diag::err_typecheck_illegal_vla); 773 InvalidDecl = true; 774 } 775 } 776 } else if (R.getTypePtr()->isFunctionType()) { 777 FunctionDecl::StorageClass SC = FunctionDecl::None; 778 switch (D.getDeclSpec().getStorageClassSpec()) { 779 default: assert(0 && "Unknown storage class!"); 780 case DeclSpec::SCS_auto: 781 case DeclSpec::SCS_register: 782 Diag(D.getIdentifierLoc(), diag::err_typecheck_sclass_func, 783 R.getAsString()); 784 InvalidDecl = true; 785 break; 786 case DeclSpec::SCS_unspecified: SC = FunctionDecl::None; break; 787 case DeclSpec::SCS_extern: SC = FunctionDecl::Extern; break; 788 case DeclSpec::SCS_static: SC = FunctionDecl::Static; break; 789 case DeclSpec::SCS_private_extern: SC = FunctionDecl::PrivateExtern;break; 790 } 791 792 bool isInline = D.getDeclSpec().isInlineSpecified(); 793 FunctionDecl *NewFD = FunctionDecl::Create(Context, CurContext, 794 D.getIdentifierLoc(), 795 II, R, SC, isInline, 796 LastDeclarator); 797 // Handle attributes. 798 HandleDeclAttributes(NewFD, D.getDeclSpec().getAttributes(), 799 D.getAttributes()); 800 801 // Copy the parameter declarations from the declarator D to 802 // the function declaration NewFD, if they are available. 803 if (D.getNumTypeObjects() > 0 && 804 D.getTypeObject(0).Fun.hasPrototype) { 805 DeclaratorChunk::FunctionTypeInfo &FTI = D.getTypeObject(0).Fun; 806 807 // Create Decl objects for each parameter, adding them to the 808 // FunctionDecl. 809 llvm::SmallVector<ParmVarDecl*, 16> Params; 810 811 // Check for C99 6.7.5.3p10 - foo(void) is a non-varargs 812 // function that takes no arguments, not a function that takes a 813 // single void argument. 814 if (FTI.NumArgs == 1 && !FTI.isVariadic && FTI.ArgInfo[0].Ident == 0 && 815 FTI.ArgInfo[0].Param && 816 !((ParmVarDecl*)FTI.ArgInfo[0].Param)->getType().getCVRQualifiers() && 817 ((ParmVarDecl*)FTI.ArgInfo[0].Param)->getType()->isVoidType()) { 818 // empty arg list, don't push any params. 819 ParmVarDecl *Param = (ParmVarDecl*)FTI.ArgInfo[0].Param; 820 821 // In C++, the empty parameter-type-list must be spelled "void"; a 822 // typedef of void is not permitted. 823 if (getLangOptions().CPlusPlus && 824 Param->getType() != Context.VoidTy) { 825 Diag(Param->getLocation(), diag::ext_param_typedef_of_void); 826 } 827 828 } else { 829 for (unsigned i = 0, e = FTI.NumArgs; i != e; ++i) 830 Params.push_back((ParmVarDecl *)FTI.ArgInfo[i].Param); 831 } 832 833 NewFD->setParams(&Params[0], Params.size()); 834 } 835 836 // Merge the decl with the existing one if appropriate. Since C functions 837 // are in a flat namespace, make sure we consider decls in outer scopes. 838 if (PrevDecl) { 839 NewFD = MergeFunctionDecl(NewFD, PrevDecl); 840 if (NewFD == 0) return 0; 841 } 842 New = NewFD; 843 844 // In C++, check default arguments now that we have merged decls. 845 if (getLangOptions().CPlusPlus) 846 CheckCXXDefaultArguments(NewFD); 847 } else { 848 if (R.getTypePtr()->isObjCInterfaceType()) { 849 Diag(D.getIdentifierLoc(), diag::err_statically_allocated_object, 850 D.getIdentifier()->getName()); 851 InvalidDecl = true; 852 } 853 854 VarDecl *NewVD; 855 VarDecl::StorageClass SC; 856 switch (D.getDeclSpec().getStorageClassSpec()) { 857 default: assert(0 && "Unknown storage class!"); 858 case DeclSpec::SCS_unspecified: SC = VarDecl::None; break; 859 case DeclSpec::SCS_extern: SC = VarDecl::Extern; break; 860 case DeclSpec::SCS_static: SC = VarDecl::Static; break; 861 case DeclSpec::SCS_auto: SC = VarDecl::Auto; break; 862 case DeclSpec::SCS_register: SC = VarDecl::Register; break; 863 case DeclSpec::SCS_private_extern: SC = VarDecl::PrivateExtern; break; 864 } 865 if (S->getParent() == 0) { 866 // C99 6.9p2: The storage-class specifiers auto and register shall not 867 // appear in the declaration specifiers in an external declaration. 868 if (SC == VarDecl::Auto || SC == VarDecl::Register) { 869 Diag(D.getIdentifierLoc(), diag::err_typecheck_sclass_fscope, 870 R.getAsString()); 871 InvalidDecl = true; 872 } 873 NewVD = FileVarDecl::Create(Context, CurContext, D.getIdentifierLoc(), 874 II, R, SC, 875 LastDeclarator); 876 } else { 877 NewVD = BlockVarDecl::Create(Context, CurContext, D.getIdentifierLoc(), 878 II, R, SC, 879 LastDeclarator); 880 } 881 // Handle attributes prior to checking for duplicates in MergeVarDecl 882 HandleDeclAttributes(NewVD, D.getDeclSpec().getAttributes(), 883 D.getAttributes()); 884 885 // Emit an error if an address space was applied to decl with local storage. 886 // This includes arrays of objects with address space qualifiers, but not 887 // automatic variables that point to other address spaces. 888 // ISO/IEC TR 18037 S5.1.2 889 if (NewVD->hasLocalStorage() && (NewVD->getType().getAddressSpace() != 0)) { 890 Diag(D.getIdentifierLoc(), diag::err_as_qualified_auto_decl); 891 InvalidDecl = true; 892 } 893 // Merge the decl with the existing one if appropriate. If the decl is 894 // in an outer scope, it isn't the same thing. 895 if (PrevDecl && S->isDeclScope(PrevDecl)) { 896 NewVD = MergeVarDecl(NewVD, PrevDecl); 897 if (NewVD == 0) return 0; 898 } 899 New = NewVD; 900 } 901 902 // If this has an identifier, add it to the scope stack. 903 if (II) 904 PushOnScopeChains(New, S); 905 // If any semantic error occurred, mark the decl as invalid. 906 if (D.getInvalidType() || InvalidDecl) 907 New->setInvalidDecl(); 908 909 return New; 910} 911 912bool Sema::CheckForConstantInitializer(Expr *Init, QualType DclT) { 913 SourceLocation loc; 914 // FIXME: Remove the isReference check and handle assignment to a reference. 915 if (!DclT->isReferenceType() && !Init->isConstantExpr(Context, &loc)) { 916 assert(loc.isValid() && "isConstantExpr didn't return a loc!"); 917 Diag(loc, diag::err_init_element_not_constant, Init->getSourceRange()); 918 return true; 919 } 920 return false; 921} 922 923void Sema::AddInitializerToDecl(DeclTy *dcl, ExprTy *init) { 924 Decl *RealDecl = static_cast<Decl *>(dcl); 925 Expr *Init = static_cast<Expr *>(init); 926 assert(Init && "missing initializer"); 927 928 // If there is no declaration, there was an error parsing it. Just ignore 929 // the initializer. 930 if (RealDecl == 0) { 931 delete Init; 932 return; 933 } 934 935 VarDecl *VDecl = dyn_cast<VarDecl>(RealDecl); 936 if (!VDecl) { 937 Diag(dyn_cast<ScopedDecl>(RealDecl)->getLocation(), 938 diag::err_illegal_initializer); 939 RealDecl->setInvalidDecl(); 940 return; 941 } 942 // Get the decls type and save a reference for later, since 943 // CheckInitializerTypes may change it. 944 QualType DclT = VDecl->getType(), SavT = DclT; 945 if (BlockVarDecl *BVD = dyn_cast<BlockVarDecl>(VDecl)) { 946 VarDecl::StorageClass SC = BVD->getStorageClass(); 947 if (SC == VarDecl::Extern) { // C99 6.7.8p5 948 Diag(VDecl->getLocation(), diag::err_block_extern_cant_init); 949 BVD->setInvalidDecl(); 950 } else if (!BVD->isInvalidDecl()) { 951 if (CheckInitializerTypes(Init, DclT)) 952 BVD->setInvalidDecl(); 953 if (SC == VarDecl::Static) // C99 6.7.8p4. 954 CheckForConstantInitializer(Init, DclT); 955 } 956 } else if (FileVarDecl *FVD = dyn_cast<FileVarDecl>(VDecl)) { 957 if (FVD->getStorageClass() == VarDecl::Extern) 958 Diag(VDecl->getLocation(), diag::warn_extern_init); 959 if (!FVD->isInvalidDecl()) 960 if (CheckInitializerTypes(Init, DclT)) 961 FVD->setInvalidDecl(); 962 963 // C99 6.7.8p4. All file scoped initializers need to be constant. 964 CheckForConstantInitializer(Init, DclT); 965 } 966 // If the type changed, it means we had an incomplete type that was 967 // completed by the initializer. For example: 968 // int ary[] = { 1, 3, 5 }; 969 // "ary" transitions from a VariableArrayType to a ConstantArrayType. 970 if (!VDecl->isInvalidDecl() && (DclT != SavT)) { 971 VDecl->setType(DclT); 972 Init->setType(DclT); 973 } 974 975 // Attach the initializer to the decl. 976 VDecl->setInit(Init); 977 return; 978} 979 980/// The declarators are chained together backwards, reverse the list. 981Sema::DeclTy *Sema::FinalizeDeclaratorGroup(Scope *S, DeclTy *group) { 982 // Often we have single declarators, handle them quickly. 983 Decl *GroupDecl = static_cast<Decl*>(group); 984 if (GroupDecl == 0) 985 return 0; 986 987 ScopedDecl *Group = dyn_cast<ScopedDecl>(GroupDecl); 988 ScopedDecl *NewGroup = 0; 989 if (Group->getNextDeclarator() == 0) 990 NewGroup = Group; 991 else { // reverse the list. 992 while (Group) { 993 ScopedDecl *Next = Group->getNextDeclarator(); 994 Group->setNextDeclarator(NewGroup); 995 NewGroup = Group; 996 Group = Next; 997 } 998 } 999 // Perform semantic analysis that depends on having fully processed both 1000 // the declarator and initializer. 1001 for (ScopedDecl *ID = NewGroup; ID; ID = ID->getNextDeclarator()) { 1002 VarDecl *IDecl = dyn_cast<VarDecl>(ID); 1003 if (!IDecl) 1004 continue; 1005 FileVarDecl *FVD = dyn_cast<FileVarDecl>(IDecl); 1006 BlockVarDecl *BVD = dyn_cast<BlockVarDecl>(IDecl); 1007 QualType T = IDecl->getType(); 1008 1009 // C99 6.7.5.2p2: If an identifier is declared to be an object with 1010 // static storage duration, it shall not have a variable length array. 1011 if ((FVD || BVD) && IDecl->getStorageClass() == VarDecl::Static) { 1012 if (T->getAsVariableArrayType()) { 1013 Diag(IDecl->getLocation(), diag::err_typecheck_illegal_vla); 1014 IDecl->setInvalidDecl(); 1015 } 1016 } 1017 // Block scope. C99 6.7p7: If an identifier for an object is declared with 1018 // no linkage (C99 6.2.2p6), the type for the object shall be complete... 1019 if (BVD && IDecl->getStorageClass() != VarDecl::Extern) { 1020 if (T->isIncompleteType() && !IDecl->isInvalidDecl()) { 1021 Diag(IDecl->getLocation(), diag::err_typecheck_decl_incomplete_type, 1022 T.getAsString()); 1023 IDecl->setInvalidDecl(); 1024 } 1025 } 1026 // File scope. C99 6.9.2p2: A declaration of an identifier for and 1027 // object that has file scope without an initializer, and without a 1028 // storage-class specifier or with the storage-class specifier "static", 1029 // constitutes a tentative definition. Note: A tentative definition with 1030 // external linkage is valid (C99 6.2.2p5). 1031 if (FVD && !FVD->getInit() && (FVD->getStorageClass() == VarDecl::Static || 1032 FVD->getStorageClass() == VarDecl::None)) { 1033 if (T->isIncompleteArrayType()) { 1034 // C99 6.9.2 (p2, p5): Implicit initialization causes an incomplete 1035 // array to be completed. Don't issue a diagnostic. 1036 } else if (T->isIncompleteType() && !IDecl->isInvalidDecl()) { 1037 // C99 6.9.2p3: If the declaration of an identifier for an object is 1038 // a tentative definition and has internal linkage (C99 6.2.2p3), the 1039 // declared type shall not be an incomplete type. 1040 Diag(IDecl->getLocation(), diag::err_typecheck_decl_incomplete_type, 1041 T.getAsString()); 1042 IDecl->setInvalidDecl(); 1043 } 1044 } 1045 } 1046 return NewGroup; 1047} 1048 1049/// ActOnParamDeclarator - Called from Parser::ParseFunctionDeclarator() 1050/// to introduce parameters into function prototype scope. 1051Sema::DeclTy * 1052Sema::ActOnParamDeclarator(Scope *S, Declarator &D) { 1053 DeclSpec &DS = D.getDeclSpec(); 1054 1055 // Verify C99 6.7.5.3p2: The only SCS allowed is 'register'. 1056 if (DS.getStorageClassSpec() != DeclSpec::SCS_unspecified && 1057 DS.getStorageClassSpec() != DeclSpec::SCS_register) { 1058 Diag(DS.getStorageClassSpecLoc(), 1059 diag::err_invalid_storage_class_in_func_decl); 1060 DS.ClearStorageClassSpecs(); 1061 } 1062 if (DS.isThreadSpecified()) { 1063 Diag(DS.getThreadSpecLoc(), 1064 diag::err_invalid_storage_class_in_func_decl); 1065 DS.ClearStorageClassSpecs(); 1066 } 1067 1068 1069 // In this context, we *do not* check D.getInvalidType(). If the declarator 1070 // type was invalid, GetTypeForDeclarator() still returns a "valid" type, 1071 // though it will not reflect the user specified type. 1072 QualType parmDeclType = GetTypeForDeclarator(D, S); 1073 1074 assert(!parmDeclType.isNull() && "GetTypeForDeclarator() returned null type"); 1075 1076 // TODO: CHECK FOR CONFLICTS, multiple decls with same name in one scope. 1077 // Can this happen for params? We already checked that they don't conflict 1078 // among each other. Here they can only shadow globals, which is ok. 1079 IdentifierInfo *II = D.getIdentifier(); 1080 if (Decl *PrevDecl = LookupDecl(II, Decl::IDNS_Ordinary, S)) { 1081 if (S->isDeclScope(PrevDecl)) { 1082 Diag(D.getIdentifierLoc(), diag::err_param_redefinition, 1083 dyn_cast<NamedDecl>(PrevDecl)->getName()); 1084 1085 // Recover by removing the name 1086 II = 0; 1087 D.SetIdentifier(0, D.getIdentifierLoc()); 1088 } 1089 } 1090 1091 // Perform the default function/array conversion (C99 6.7.5.3p[7,8]). 1092 // Doing the promotion here has a win and a loss. The win is the type for 1093 // both Decl's and DeclRefExpr's will match (a convenient invariant for the 1094 // code generator). The loss is the orginal type isn't preserved. For example: 1095 // 1096 // void func(int parmvardecl[5]) { // convert "int [5]" to "int *" 1097 // int blockvardecl[5]; 1098 // sizeof(parmvardecl); // size == 4 1099 // sizeof(blockvardecl); // size == 20 1100 // } 1101 // 1102 // For expressions, all implicit conversions are captured using the 1103 // ImplicitCastExpr AST node (we have no such mechanism for Decl's). 1104 // 1105 // FIXME: If a source translation tool needs to see the original type, then 1106 // we need to consider storing both types (in ParmVarDecl)... 1107 // 1108 if (parmDeclType->isArrayType()) { 1109 // int x[restrict 4] -> int *restrict 1110 parmDeclType = Context.getArrayDecayedType(parmDeclType); 1111 } else if (parmDeclType->isFunctionType()) 1112 parmDeclType = Context.getPointerType(parmDeclType); 1113 1114 ParmVarDecl *New = ParmVarDecl::Create(Context, CurContext, 1115 D.getIdentifierLoc(), II, 1116 parmDeclType, VarDecl::None, 1117 0, 0); 1118 1119 if (D.getInvalidType()) 1120 New->setInvalidDecl(); 1121 1122 if (II) 1123 PushOnScopeChains(New, S); 1124 1125 HandleDeclAttributes(New, D.getAttributes(), 0); 1126 return New; 1127 1128} 1129 1130Sema::DeclTy *Sema::ActOnStartOfFunctionDef(Scope *FnBodyScope, Declarator &D) { 1131 assert(CurFunctionDecl == 0 && "Function parsing confused"); 1132 assert(D.getTypeObject(0).Kind == DeclaratorChunk::Function && 1133 "Not a function declarator!"); 1134 DeclaratorChunk::FunctionTypeInfo &FTI = D.getTypeObject(0).Fun; 1135 1136 // Verify 6.9.1p6: 'every identifier in the identifier list shall be declared' 1137 // for a K&R function. 1138 if (!FTI.hasPrototype) { 1139 for (unsigned i = 0, e = FTI.NumArgs; i != e; ++i) { 1140 if (FTI.ArgInfo[i].Param == 0) { 1141 Diag(FTI.ArgInfo[i].IdentLoc, diag::ext_param_not_declared, 1142 FTI.ArgInfo[i].Ident->getName()); 1143 // Implicitly declare the argument as type 'int' for lack of a better 1144 // type. 1145 DeclSpec DS; 1146 const char* PrevSpec; // unused 1147 DS.SetTypeSpecType(DeclSpec::TST_int, FTI.ArgInfo[i].IdentLoc, 1148 PrevSpec); 1149 Declarator ParamD(DS, Declarator::KNRTypeListContext); 1150 ParamD.SetIdentifier(FTI.ArgInfo[i].Ident, FTI.ArgInfo[i].IdentLoc); 1151 FTI.ArgInfo[i].Param = ActOnParamDeclarator(FnBodyScope, ParamD); 1152 } 1153 } 1154 1155 // Since this is a function definition, act as though we have information 1156 // about the arguments. 1157 if (FTI.NumArgs) 1158 FTI.hasPrototype = true; 1159 } else { 1160 // FIXME: Diagnose arguments without names in C. 1161 } 1162 1163 Scope *GlobalScope = FnBodyScope->getParent(); 1164 1165 // See if this is a redefinition. 1166 Decl *PrevDcl = LookupDecl(D.getIdentifier(), Decl::IDNS_Ordinary, 1167 GlobalScope); 1168 if (FunctionDecl *FD = dyn_cast_or_null<FunctionDecl>(PrevDcl)) { 1169 if (FD->getBody()) { 1170 Diag(D.getIdentifierLoc(), diag::err_redefinition, 1171 D.getIdentifier()->getName()); 1172 Diag(FD->getLocation(), diag::err_previous_definition); 1173 } 1174 } 1175 Decl *decl = static_cast<Decl*>(ActOnDeclarator(GlobalScope, D, 0)); 1176 FunctionDecl *FD = cast<FunctionDecl>(decl); 1177 CurFunctionDecl = FD; 1178 PushDeclContext(FD); 1179 1180 // Check the validity of our function parameters 1181 CheckParmsForFunctionDef(FD); 1182 1183 // Introduce our parameters into the function scope 1184 for (unsigned p = 0, NumParams = FD->getNumParams(); p < NumParams; ++p) { 1185 ParmVarDecl *Param = FD->getParamDecl(p); 1186 // If this has an identifier, add it to the scope stack. 1187 if (Param->getIdentifier()) 1188 PushOnScopeChains(Param, FnBodyScope); 1189 } 1190 1191 return FD; 1192} 1193 1194Sema::DeclTy *Sema::ActOnFinishFunctionBody(DeclTy *D, StmtTy *Body) { 1195 Decl *dcl = static_cast<Decl *>(D); 1196 if (FunctionDecl *FD = dyn_cast<FunctionDecl>(dcl)) { 1197 FD->setBody((Stmt*)Body); 1198 assert(FD == CurFunctionDecl && "Function parsing confused"); 1199 CurFunctionDecl = 0; 1200 } else if (ObjCMethodDecl *MD = dyn_cast<ObjCMethodDecl>(dcl)) { 1201 MD->setBody((Stmt*)Body); 1202 CurMethodDecl = 0; 1203 } 1204 PopDeclContext(); 1205 // Verify and clean out per-function state. 1206 1207 // Check goto/label use. 1208 for (llvm::DenseMap<IdentifierInfo*, LabelStmt*>::iterator 1209 I = LabelMap.begin(), E = LabelMap.end(); I != E; ++I) { 1210 // Verify that we have no forward references left. If so, there was a goto 1211 // or address of a label taken, but no definition of it. Label fwd 1212 // definitions are indicated with a null substmt. 1213 if (I->second->getSubStmt() == 0) { 1214 LabelStmt *L = I->second; 1215 // Emit error. 1216 Diag(L->getIdentLoc(), diag::err_undeclared_label_use, L->getName()); 1217 1218 // At this point, we have gotos that use the bogus label. Stitch it into 1219 // the function body so that they aren't leaked and that the AST is well 1220 // formed. 1221 if (Body) { 1222 L->setSubStmt(new NullStmt(L->getIdentLoc())); 1223 cast<CompoundStmt>((Stmt*)Body)->push_back(L); 1224 } else { 1225 // The whole function wasn't parsed correctly, just delete this. 1226 delete L; 1227 } 1228 } 1229 } 1230 LabelMap.clear(); 1231 1232 return D; 1233} 1234 1235/// ImplicitlyDefineFunction - An undeclared identifier was used in a function 1236/// call, forming a call to an implicitly defined function (per C99 6.5.1p2). 1237ScopedDecl *Sema::ImplicitlyDefineFunction(SourceLocation Loc, 1238 IdentifierInfo &II, Scope *S) { 1239 if (getLangOptions().C99) // Extension in C99. 1240 Diag(Loc, diag::ext_implicit_function_decl, II.getName()); 1241 else // Legal in C90, but warn about it. 1242 Diag(Loc, diag::warn_implicit_function_decl, II.getName()); 1243 1244 // FIXME: handle stuff like: 1245 // void foo() { extern float X(); } 1246 // void bar() { X(); } <-- implicit decl for X in another scope. 1247 1248 // Set a Declarator for the implicit definition: int foo(); 1249 const char *Dummy; 1250 DeclSpec DS; 1251 bool Error = DS.SetTypeSpecType(DeclSpec::TST_int, Loc, Dummy); 1252 Error = Error; // Silence warning. 1253 assert(!Error && "Error setting up implicit decl!"); 1254 Declarator D(DS, Declarator::BlockContext); 1255 D.AddTypeInfo(DeclaratorChunk::getFunction(false, false, 0, 0, Loc)); 1256 D.SetIdentifier(&II, Loc); 1257 1258 // Find translation-unit scope to insert this function into. 1259 if (Scope *FnS = S->getFnParent()) 1260 S = FnS->getParent(); // Skip all scopes in a function at once. 1261 while (S->getParent()) 1262 S = S->getParent(); 1263 1264 FunctionDecl *FD = 1265 dyn_cast<FunctionDecl>(static_cast<Decl*>(ActOnDeclarator(S, D, 0))); 1266 FD->setImplicit(); 1267 return FD; 1268} 1269 1270 1271TypedefDecl *Sema::ParseTypedefDecl(Scope *S, Declarator &D, QualType T, 1272 ScopedDecl *LastDeclarator) { 1273 assert(D.getIdentifier() && "Wrong callback for declspec without declarator"); 1274 assert(!T.isNull() && "GetTypeForDeclarator() returned null type"); 1275 1276 // Scope manipulation handled by caller. 1277 TypedefDecl *NewTD = TypedefDecl::Create(Context, CurContext, 1278 D.getIdentifierLoc(), 1279 D.getIdentifier(), 1280 T, LastDeclarator); 1281 if (D.getInvalidType()) 1282 NewTD->setInvalidDecl(); 1283 return NewTD; 1284} 1285 1286/// ActOnTag - This is invoked when we see 'struct foo' or 'struct {'. In the 1287/// former case, Name will be non-null. In the later case, Name will be null. 1288/// TagType indicates what kind of tag this is. TK indicates whether this is a 1289/// reference/declaration/definition of a tag. 1290Sema::DeclTy *Sema::ActOnTag(Scope *S, unsigned TagType, TagKind TK, 1291 SourceLocation KWLoc, IdentifierInfo *Name, 1292 SourceLocation NameLoc, AttributeList *Attr) { 1293 // If this is a use of an existing tag, it must have a name. 1294 assert((Name != 0 || TK == TK_Definition) && 1295 "Nameless record must be a definition!"); 1296 1297 Decl::Kind Kind; 1298 switch (TagType) { 1299 default: assert(0 && "Unknown tag type!"); 1300 case DeclSpec::TST_struct: Kind = Decl::Struct; break; 1301 case DeclSpec::TST_union: Kind = Decl::Union; break; 1302//case DeclSpec::TST_class: Kind = Decl::Class; break; 1303 case DeclSpec::TST_enum: Kind = Decl::Enum; break; 1304 } 1305 1306 // If this is a named struct, check to see if there was a previous forward 1307 // declaration or definition. 1308 if (TagDecl *PrevDecl = 1309 dyn_cast_or_null<TagDecl>(LookupDecl(Name, Decl::IDNS_Tag, S))) { 1310 1311 // If this is a use of a previous tag, or if the tag is already declared in 1312 // the same scope (so that the definition/declaration completes or 1313 // rementions the tag), reuse the decl. 1314 if (TK == TK_Reference || S->isDeclScope(PrevDecl)) { 1315 // Make sure that this wasn't declared as an enum and now used as a struct 1316 // or something similar. 1317 if (PrevDecl->getKind() != Kind) { 1318 Diag(KWLoc, diag::err_use_with_wrong_tag, Name->getName()); 1319 Diag(PrevDecl->getLocation(), diag::err_previous_use); 1320 } 1321 1322 // If this is a use or a forward declaration, we're good. 1323 if (TK != TK_Definition) 1324 return PrevDecl; 1325 1326 // Diagnose attempts to redefine a tag. 1327 if (PrevDecl->isDefinition()) { 1328 Diag(NameLoc, diag::err_redefinition, Name->getName()); 1329 Diag(PrevDecl->getLocation(), diag::err_previous_definition); 1330 // If this is a redefinition, recover by making this struct be 1331 // anonymous, which will make any later references get the previous 1332 // definition. 1333 Name = 0; 1334 } else { 1335 // Okay, this is definition of a previously declared or referenced tag. 1336 // Move the location of the decl to be the definition site. 1337 PrevDecl->setLocation(NameLoc); 1338 return PrevDecl; 1339 } 1340 } 1341 // If we get here, this is a definition of a new struct type in a nested 1342 // scope, e.g. "struct foo; void bar() { struct foo; }", just create a new 1343 // type. 1344 } 1345 1346 // If there is an identifier, use the location of the identifier as the 1347 // location of the decl, otherwise use the location of the struct/union 1348 // keyword. 1349 SourceLocation Loc = NameLoc.isValid() ? NameLoc : KWLoc; 1350 1351 // Otherwise, if this is the first time we've seen this tag, create the decl. 1352 TagDecl *New; 1353 switch (Kind) { 1354 default: assert(0 && "Unknown tag kind!"); 1355 case Decl::Enum: 1356 // FIXME: Tag decls should be chained to any simultaneous vardecls, e.g.: 1357 // enum X { A, B, C } D; D should chain to X. 1358 New = EnumDecl::Create(Context, CurContext, Loc, Name, 0); 1359 // If this is an undefined enum, warn. 1360 if (TK != TK_Definition) Diag(Loc, diag::ext_forward_ref_enum); 1361 break; 1362 case Decl::Union: 1363 case Decl::Struct: 1364 case Decl::Class: 1365 // FIXME: Tag decls should be chained to any simultaneous vardecls, e.g.: 1366 // struct X { int A; } D; D should chain to X. 1367 New = RecordDecl::Create(Context, Kind, CurContext, Loc, Name, 0); 1368 break; 1369 } 1370 1371 // If this has an identifier, add it to the scope stack. 1372 if (Name) { 1373 // The scope passed in may not be a decl scope. Zip up the scope tree until 1374 // we find one that is. 1375 while ((S->getFlags() & Scope::DeclScope) == 0) 1376 S = S->getParent(); 1377 1378 // Add it to the decl chain. 1379 PushOnScopeChains(New, S); 1380 } 1381 1382 HandleDeclAttributes(New, Attr, 0); 1383 return New; 1384} 1385 1386/// ActOnField - Each field of a struct/union/class is passed into this in order 1387/// to create a FieldDecl object for it. 1388Sema::DeclTy *Sema::ActOnField(Scope *S, 1389 SourceLocation DeclStart, 1390 Declarator &D, ExprTy *BitfieldWidth) { 1391 IdentifierInfo *II = D.getIdentifier(); 1392 Expr *BitWidth = (Expr*)BitfieldWidth; 1393 SourceLocation Loc = DeclStart; 1394 if (II) Loc = D.getIdentifierLoc(); 1395 1396 // FIXME: Unnamed fields can be handled in various different ways, for 1397 // example, unnamed unions inject all members into the struct namespace! 1398 1399 1400 if (BitWidth) { 1401 // TODO: Validate. 1402 //printf("WARNING: BITFIELDS IGNORED!\n"); 1403 1404 // 6.7.2.1p3 1405 // 6.7.2.1p4 1406 1407 } else { 1408 // Not a bitfield. 1409 1410 // validate II. 1411 1412 } 1413 1414 QualType T = GetTypeForDeclarator(D, S); 1415 assert(!T.isNull() && "GetTypeForDeclarator() returned null type"); 1416 bool InvalidDecl = false; 1417 1418 // C99 6.7.2.1p8: A member of a structure or union may have any type other 1419 // than a variably modified type. 1420 if (T->isVariablyModifiedType()) { 1421 // FIXME: This diagnostic needs work 1422 Diag(Loc, diag::err_typecheck_illegal_vla, Loc); 1423 InvalidDecl = true; 1424 } 1425 // FIXME: Chain fielddecls together. 1426 FieldDecl *NewFD = FieldDecl::Create(Context, Loc, II, T, BitWidth); 1427 1428 HandleDeclAttributes(NewFD, D.getDeclSpec().getAttributes(), 1429 D.getAttributes()); 1430 1431 if (D.getInvalidType() || InvalidDecl) 1432 NewFD->setInvalidDecl(); 1433 return NewFD; 1434} 1435 1436/// TranslateIvarVisibility - Translate visibility from a token ID to an 1437/// AST enum value. 1438static ObjCIvarDecl::AccessControl 1439TranslateIvarVisibility(tok::ObjCKeywordKind ivarVisibility) { 1440 switch (ivarVisibility) { 1441 case tok::objc_private: return ObjCIvarDecl::Private; 1442 case tok::objc_public: return ObjCIvarDecl::Public; 1443 case tok::objc_protected: return ObjCIvarDecl::Protected; 1444 case tok::objc_package: return ObjCIvarDecl::Package; 1445 default: assert(false && "Unknown visitibility kind"); 1446 } 1447} 1448 1449/// ActOnIvar - Each ivar field of an objective-c class is passed into this 1450/// in order to create an IvarDecl object for it. 1451Sema::DeclTy *Sema::ActOnIvar(Scope *S, 1452 SourceLocation DeclStart, 1453 Declarator &D, ExprTy *BitfieldWidth, 1454 tok::ObjCKeywordKind Visibility) { 1455 IdentifierInfo *II = D.getIdentifier(); 1456 Expr *BitWidth = (Expr*)BitfieldWidth; 1457 SourceLocation Loc = DeclStart; 1458 if (II) Loc = D.getIdentifierLoc(); 1459 1460 // FIXME: Unnamed fields can be handled in various different ways, for 1461 // example, unnamed unions inject all members into the struct namespace! 1462 1463 1464 if (BitWidth) { 1465 // TODO: Validate. 1466 //printf("WARNING: BITFIELDS IGNORED!\n"); 1467 1468 // 6.7.2.1p3 1469 // 6.7.2.1p4 1470 1471 } else { 1472 // Not a bitfield. 1473 1474 // validate II. 1475 1476 } 1477 1478 QualType T = GetTypeForDeclarator(D, S); 1479 assert(!T.isNull() && "GetTypeForDeclarator() returned null type"); 1480 bool InvalidDecl = false; 1481 1482 // C99 6.7.2.1p8: A member of a structure or union may have any type other 1483 // than a variably modified type. 1484 if (T->isVariablyModifiedType()) { 1485 // FIXME: This diagnostic needs work 1486 Diag(Loc, diag::err_typecheck_illegal_vla, Loc); 1487 InvalidDecl = true; 1488 } 1489 1490 ObjCIvarDecl *NewID = ObjCIvarDecl::Create(Context, Loc, II, T); 1491 1492 HandleDeclAttributes(NewID, D.getDeclSpec().getAttributes(), 1493 D.getAttributes()); 1494 1495 if (D.getInvalidType() || InvalidDecl) 1496 NewID->setInvalidDecl(); 1497 // If we have visibility info, make sure the AST is set accordingly. 1498 if (Visibility != tok::objc_not_keyword) 1499 NewID->setAccessControl(TranslateIvarVisibility(Visibility)); 1500 return NewID; 1501} 1502 1503void Sema::ActOnFields(Scope* S, 1504 SourceLocation RecLoc, DeclTy *RecDecl, 1505 DeclTy **Fields, unsigned NumFields, 1506 SourceLocation LBrac, SourceLocation RBrac) { 1507 Decl *EnclosingDecl = static_cast<Decl*>(RecDecl); 1508 assert(EnclosingDecl && "missing record or interface decl"); 1509 RecordDecl *Record = dyn_cast<RecordDecl>(EnclosingDecl); 1510 1511 if (Record && Record->isDefinition()) { 1512 // Diagnose code like: 1513 // struct S { struct S {} X; }; 1514 // We discover this when we complete the outer S. Reject and ignore the 1515 // outer S. 1516 Diag(Record->getLocation(), diag::err_nested_redefinition, 1517 Record->getKindName()); 1518 Diag(RecLoc, diag::err_previous_definition); 1519 Record->setInvalidDecl(); 1520 return; 1521 } 1522 // Verify that all the fields are okay. 1523 unsigned NumNamedMembers = 0; 1524 llvm::SmallVector<FieldDecl*, 32> RecFields; 1525 llvm::SmallSet<const IdentifierInfo*, 32> FieldIDs; 1526 1527 for (unsigned i = 0; i != NumFields; ++i) { 1528 1529 FieldDecl *FD = cast_or_null<FieldDecl>(static_cast<Decl*>(Fields[i])); 1530 assert(FD && "missing field decl"); 1531 1532 // Remember all fields. 1533 RecFields.push_back(FD); 1534 1535 // Get the type for the field. 1536 Type *FDTy = FD->getType().getTypePtr(); 1537 1538 // C99 6.7.2.1p2 - A field may not be a function type. 1539 if (FDTy->isFunctionType()) { 1540 Diag(FD->getLocation(), diag::err_field_declared_as_function, 1541 FD->getName()); 1542 FD->setInvalidDecl(); 1543 EnclosingDecl->setInvalidDecl(); 1544 continue; 1545 } 1546 // C99 6.7.2.1p2 - A field may not be an incomplete type except... 1547 if (FDTy->isIncompleteType()) { 1548 if (!Record) { // Incomplete ivar type is always an error. 1549 Diag(FD->getLocation(), diag::err_field_incomplete, FD->getName()); 1550 FD->setInvalidDecl(); 1551 EnclosingDecl->setInvalidDecl(); 1552 continue; 1553 } 1554 if (i != NumFields-1 || // ... that the last member ... 1555 Record->getKind() != Decl::Struct || // ... of a structure ... 1556 !FDTy->isArrayType()) { //... may have incomplete array type. 1557 Diag(FD->getLocation(), diag::err_field_incomplete, FD->getName()); 1558 FD->setInvalidDecl(); 1559 EnclosingDecl->setInvalidDecl(); 1560 continue; 1561 } 1562 if (NumNamedMembers < 1) { //... must have more than named member ... 1563 Diag(FD->getLocation(), diag::err_flexible_array_empty_struct, 1564 FD->getName()); 1565 FD->setInvalidDecl(); 1566 EnclosingDecl->setInvalidDecl(); 1567 continue; 1568 } 1569 // Okay, we have a legal flexible array member at the end of the struct. 1570 if (Record) 1571 Record->setHasFlexibleArrayMember(true); 1572 } 1573 /// C99 6.7.2.1p2 - a struct ending in a flexible array member cannot be the 1574 /// field of another structure or the element of an array. 1575 if (const RecordType *FDTTy = FDTy->getAsRecordType()) { 1576 if (FDTTy->getDecl()->hasFlexibleArrayMember()) { 1577 // If this is a member of a union, then entire union becomes "flexible". 1578 if (Record && Record->getKind() == Decl::Union) { 1579 Record->setHasFlexibleArrayMember(true); 1580 } else { 1581 // If this is a struct/class and this is not the last element, reject 1582 // it. Note that GCC supports variable sized arrays in the middle of 1583 // structures. 1584 if (i != NumFields-1) { 1585 Diag(FD->getLocation(), diag::err_variable_sized_type_in_struct, 1586 FD->getName()); 1587 FD->setInvalidDecl(); 1588 EnclosingDecl->setInvalidDecl(); 1589 continue; 1590 } 1591 // We support flexible arrays at the end of structs in other structs 1592 // as an extension. 1593 Diag(FD->getLocation(), diag::ext_flexible_array_in_struct, 1594 FD->getName()); 1595 if (Record) 1596 Record->setHasFlexibleArrayMember(true); 1597 } 1598 } 1599 } 1600 /// A field cannot be an Objective-c object 1601 if (FDTy->isObjCInterfaceType()) { 1602 Diag(FD->getLocation(), diag::err_statically_allocated_object, 1603 FD->getName()); 1604 FD->setInvalidDecl(); 1605 EnclosingDecl->setInvalidDecl(); 1606 continue; 1607 } 1608 // Keep track of the number of named members. 1609 if (IdentifierInfo *II = FD->getIdentifier()) { 1610 // Detect duplicate member names. 1611 if (!FieldIDs.insert(II)) { 1612 Diag(FD->getLocation(), diag::err_duplicate_member, II->getName()); 1613 // Find the previous decl. 1614 SourceLocation PrevLoc; 1615 for (unsigned i = 0, e = RecFields.size(); ; ++i) { 1616 assert(i != e && "Didn't find previous def!"); 1617 if (RecFields[i]->getIdentifier() == II) { 1618 PrevLoc = RecFields[i]->getLocation(); 1619 break; 1620 } 1621 } 1622 Diag(PrevLoc, diag::err_previous_definition); 1623 FD->setInvalidDecl(); 1624 EnclosingDecl->setInvalidDecl(); 1625 continue; 1626 } 1627 ++NumNamedMembers; 1628 } 1629 } 1630 1631 // Okay, we successfully defined 'Record'. 1632 if (Record) { 1633 Record->defineBody(&RecFields[0], RecFields.size()); 1634 Consumer.HandleTagDeclDefinition(Record); 1635 } else { 1636 ObjCIvarDecl **ClsFields = reinterpret_cast<ObjCIvarDecl**>(&RecFields[0]); 1637 if (ObjCInterfaceDecl *ID = dyn_cast<ObjCInterfaceDecl>(EnclosingDecl)) 1638 ID->addInstanceVariablesToClass(ClsFields, RecFields.size(), RBrac); 1639 else if (ObjCImplementationDecl *IMPDecl = 1640 dyn_cast<ObjCImplementationDecl>(EnclosingDecl)) { 1641 assert(IMPDecl && "ActOnFields - missing ObjCImplementationDecl"); 1642 IMPDecl->ObjCAddInstanceVariablesToClassImpl(ClsFields, RecFields.size()); 1643 CheckImplementationIvars(IMPDecl, ClsFields, RecFields.size(), RBrac); 1644 } 1645 } 1646} 1647 1648Sema::DeclTy *Sema::ActOnEnumConstant(Scope *S, DeclTy *theEnumDecl, 1649 DeclTy *lastEnumConst, 1650 SourceLocation IdLoc, IdentifierInfo *Id, 1651 SourceLocation EqualLoc, ExprTy *val) { 1652 EnumDecl *TheEnumDecl = cast<EnumDecl>(static_cast<Decl*>(theEnumDecl)); 1653 EnumConstantDecl *LastEnumConst = 1654 cast_or_null<EnumConstantDecl>(static_cast<Decl*>(lastEnumConst)); 1655 Expr *Val = static_cast<Expr*>(val); 1656 1657 // The scope passed in may not be a decl scope. Zip up the scope tree until 1658 // we find one that is. 1659 while ((S->getFlags() & Scope::DeclScope) == 0) 1660 S = S->getParent(); 1661 1662 // Verify that there isn't already something declared with this name in this 1663 // scope. 1664 if (Decl *PrevDecl = LookupDecl(Id, Decl::IDNS_Ordinary, S)) { 1665 if (S->isDeclScope(PrevDecl)) { 1666 if (isa<EnumConstantDecl>(PrevDecl)) 1667 Diag(IdLoc, diag::err_redefinition_of_enumerator, Id->getName()); 1668 else 1669 Diag(IdLoc, diag::err_redefinition, Id->getName()); 1670 Diag(PrevDecl->getLocation(), diag::err_previous_definition); 1671 delete Val; 1672 return 0; 1673 } 1674 } 1675 1676 llvm::APSInt EnumVal(32); 1677 QualType EltTy; 1678 if (Val) { 1679 // Make sure to promote the operand type to int. 1680 UsualUnaryConversions(Val); 1681 1682 // C99 6.7.2.2p2: Make sure we have an integer constant expression. 1683 SourceLocation ExpLoc; 1684 if (!Val->isIntegerConstantExpr(EnumVal, Context, &ExpLoc)) { 1685 Diag(ExpLoc, diag::err_enum_value_not_integer_constant_expr, 1686 Id->getName()); 1687 delete Val; 1688 Val = 0; // Just forget about it. 1689 } else { 1690 EltTy = Val->getType(); 1691 } 1692 } 1693 1694 if (!Val) { 1695 if (LastEnumConst) { 1696 // Assign the last value + 1. 1697 EnumVal = LastEnumConst->getInitVal(); 1698 ++EnumVal; 1699 1700 // Check for overflow on increment. 1701 if (EnumVal < LastEnumConst->getInitVal()) 1702 Diag(IdLoc, diag::warn_enum_value_overflow); 1703 1704 EltTy = LastEnumConst->getType(); 1705 } else { 1706 // First value, set to zero. 1707 EltTy = Context.IntTy; 1708 EnumVal.zextOrTrunc(static_cast<uint32_t>(Context.getTypeSize(EltTy))); 1709 } 1710 } 1711 1712 EnumConstantDecl *New = 1713 EnumConstantDecl::Create(Context, TheEnumDecl, IdLoc, Id, EltTy, 1714 Val, EnumVal, 1715 LastEnumConst); 1716 1717 // Register this decl in the current scope stack. 1718 PushOnScopeChains(New, S); 1719 return New; 1720} 1721 1722void Sema::ActOnEnumBody(SourceLocation EnumLoc, DeclTy *EnumDeclX, 1723 DeclTy **Elements, unsigned NumElements) { 1724 EnumDecl *Enum = cast<EnumDecl>(static_cast<Decl*>(EnumDeclX)); 1725 assert(!Enum->isDefinition() && "Enum redefinitions can't reach here"); 1726 1727 // TODO: If the result value doesn't fit in an int, it must be a long or long 1728 // long value. ISO C does not support this, but GCC does as an extension, 1729 // emit a warning. 1730 unsigned IntWidth = Context.Target.getIntWidth(); 1731 1732 // Verify that all the values are okay, compute the size of the values, and 1733 // reverse the list. 1734 unsigned NumNegativeBits = 0; 1735 unsigned NumPositiveBits = 0; 1736 1737 // Keep track of whether all elements have type int. 1738 bool AllElementsInt = true; 1739 1740 EnumConstantDecl *EltList = 0; 1741 for (unsigned i = 0; i != NumElements; ++i) { 1742 EnumConstantDecl *ECD = 1743 cast_or_null<EnumConstantDecl>(static_cast<Decl*>(Elements[i])); 1744 if (!ECD) continue; // Already issued a diagnostic. 1745 1746 // If the enum value doesn't fit in an int, emit an extension warning. 1747 const llvm::APSInt &InitVal = ECD->getInitVal(); 1748 assert(InitVal.getBitWidth() >= IntWidth && 1749 "Should have promoted value to int"); 1750 if (InitVal.getBitWidth() > IntWidth) { 1751 llvm::APSInt V(InitVal); 1752 V.trunc(IntWidth); 1753 V.extend(InitVal.getBitWidth()); 1754 if (V != InitVal) 1755 Diag(ECD->getLocation(), diag::ext_enum_value_not_int, 1756 InitVal.toString()); 1757 } 1758 1759 // Keep track of the size of positive and negative values. 1760 if (InitVal.isUnsigned() || InitVal.isNonNegative()) 1761 NumPositiveBits = std::max(NumPositiveBits, 1762 (unsigned)InitVal.getActiveBits()); 1763 else 1764 NumNegativeBits = std::max(NumNegativeBits, 1765 (unsigned)InitVal.getMinSignedBits()); 1766 1767 // Keep track of whether every enum element has type int (very commmon). 1768 if (AllElementsInt) 1769 AllElementsInt = ECD->getType() == Context.IntTy; 1770 1771 ECD->setNextDeclarator(EltList); 1772 EltList = ECD; 1773 } 1774 1775 // Figure out the type that should be used for this enum. 1776 // FIXME: Support attribute(packed) on enums and -fshort-enums. 1777 QualType BestType; 1778 unsigned BestWidth; 1779 1780 if (NumNegativeBits) { 1781 // If there is a negative value, figure out the smallest integer type (of 1782 // int/long/longlong) that fits. 1783 if (NumNegativeBits <= IntWidth && NumPositiveBits < IntWidth) { 1784 BestType = Context.IntTy; 1785 BestWidth = IntWidth; 1786 } else { 1787 BestWidth = Context.Target.getLongWidth(); 1788 1789 if (NumNegativeBits <= BestWidth && NumPositiveBits < BestWidth) 1790 BestType = Context.LongTy; 1791 else { 1792 BestWidth = Context.Target.getLongLongWidth(); 1793 1794 if (NumNegativeBits > BestWidth || NumPositiveBits >= BestWidth) 1795 Diag(Enum->getLocation(), diag::warn_enum_too_large); 1796 BestType = Context.LongLongTy; 1797 } 1798 } 1799 } else { 1800 // If there is no negative value, figure out which of uint, ulong, ulonglong 1801 // fits. 1802 if (NumPositiveBits <= IntWidth) { 1803 BestType = Context.UnsignedIntTy; 1804 BestWidth = IntWidth; 1805 } else if (NumPositiveBits <= 1806 (BestWidth = Context.Target.getLongWidth())) { 1807 BestType = Context.UnsignedLongTy; 1808 } else { 1809 BestWidth = Context.Target.getLongLongWidth(); 1810 assert(NumPositiveBits <= BestWidth && 1811 "How could an initializer get larger than ULL?"); 1812 BestType = Context.UnsignedLongLongTy; 1813 } 1814 } 1815 1816 // Loop over all of the enumerator constants, changing their types to match 1817 // the type of the enum if needed. 1818 for (unsigned i = 0; i != NumElements; ++i) { 1819 EnumConstantDecl *ECD = 1820 cast_or_null<EnumConstantDecl>(static_cast<Decl*>(Elements[i])); 1821 if (!ECD) continue; // Already issued a diagnostic. 1822 1823 // Standard C says the enumerators have int type, but we allow, as an 1824 // extension, the enumerators to be larger than int size. If each 1825 // enumerator value fits in an int, type it as an int, otherwise type it the 1826 // same as the enumerator decl itself. This means that in "enum { X = 1U }" 1827 // that X has type 'int', not 'unsigned'. 1828 if (ECD->getType() == Context.IntTy) { 1829 // Make sure the init value is signed. 1830 llvm::APSInt IV = ECD->getInitVal(); 1831 IV.setIsSigned(true); 1832 ECD->setInitVal(IV); 1833 continue; // Already int type. 1834 } 1835 1836 // Determine whether the value fits into an int. 1837 llvm::APSInt InitVal = ECD->getInitVal(); 1838 bool FitsInInt; 1839 if (InitVal.isUnsigned() || !InitVal.isNegative()) 1840 FitsInInt = InitVal.getActiveBits() < IntWidth; 1841 else 1842 FitsInInt = InitVal.getMinSignedBits() <= IntWidth; 1843 1844 // If it fits into an integer type, force it. Otherwise force it to match 1845 // the enum decl type. 1846 QualType NewTy; 1847 unsigned NewWidth; 1848 bool NewSign; 1849 if (FitsInInt) { 1850 NewTy = Context.IntTy; 1851 NewWidth = IntWidth; 1852 NewSign = true; 1853 } else if (ECD->getType() == BestType) { 1854 // Already the right type! 1855 continue; 1856 } else { 1857 NewTy = BestType; 1858 NewWidth = BestWidth; 1859 NewSign = BestType->isSignedIntegerType(); 1860 } 1861 1862 // Adjust the APSInt value. 1863 InitVal.extOrTrunc(NewWidth); 1864 InitVal.setIsSigned(NewSign); 1865 ECD->setInitVal(InitVal); 1866 1867 // Adjust the Expr initializer and type. 1868 ECD->setInitExpr(new ImplicitCastExpr(NewTy, ECD->getInitExpr())); 1869 ECD->setType(NewTy); 1870 } 1871 1872 Enum->defineElements(EltList, BestType); 1873 Consumer.HandleTagDeclDefinition(Enum); 1874} 1875 1876Sema::DeclTy *Sema::ActOnFileScopeAsmDecl(SourceLocation Loc, 1877 ExprTy *expr) { 1878 StringLiteral *AsmString = cast<StringLiteral>((Expr*)expr); 1879 1880 return FileScopeAsmDecl::Create(Context, Loc, AsmString); 1881} 1882 1883Sema::DeclTy* Sema::ActOnLinkageSpec(SourceLocation Loc, 1884 SourceLocation LBrace, 1885 SourceLocation RBrace, 1886 const char *Lang, 1887 unsigned StrSize, 1888 DeclTy *D) { 1889 LinkageSpecDecl::LanguageIDs Language; 1890 Decl *dcl = static_cast<Decl *>(D); 1891 if (strncmp(Lang, "\"C\"", StrSize) == 0) 1892 Language = LinkageSpecDecl::lang_c; 1893 else if (strncmp(Lang, "\"C++\"", StrSize) == 0) 1894 Language = LinkageSpecDecl::lang_cxx; 1895 else { 1896 Diag(Loc, diag::err_bad_language); 1897 return 0; 1898 } 1899 1900 // FIXME: Add all the various semantics of linkage specifications 1901 return LinkageSpecDecl::Create(Context, Loc, Language, dcl); 1902} 1903 1904void Sema::HandleDeclAttribute(Decl *New, AttributeList *Attr) { 1905 1906 switch (Attr->getKind()) { 1907 case AttributeList::AT_vector_size: 1908 if (ValueDecl *vDecl = dyn_cast<ValueDecl>(New)) { 1909 QualType newType = HandleVectorTypeAttribute(vDecl->getType(), Attr); 1910 if (!newType.isNull()) // install the new vector type into the decl 1911 vDecl->setType(newType); 1912 } 1913 if (TypedefDecl *tDecl = dyn_cast<TypedefDecl>(New)) { 1914 QualType newType = HandleVectorTypeAttribute(tDecl->getUnderlyingType(), 1915 Attr); 1916 if (!newType.isNull()) // install the new vector type into the decl 1917 tDecl->setUnderlyingType(newType); 1918 } 1919 break; 1920 case AttributeList::AT_ocu_vector_type: 1921 if (TypedefDecl *tDecl = dyn_cast<TypedefDecl>(New)) 1922 HandleOCUVectorTypeAttribute(tDecl, Attr); 1923 else 1924 Diag(Attr->getLoc(), 1925 diag::err_typecheck_ocu_vector_not_typedef); 1926 break; 1927 case AttributeList::AT_address_space: 1928 if (TypedefDecl *tDecl = dyn_cast<TypedefDecl>(New)) { 1929 QualType newType = HandleAddressSpaceTypeAttribute( 1930 tDecl->getUnderlyingType(), 1931 Attr); 1932 tDecl->setUnderlyingType(newType); 1933 } else if (ValueDecl *vDecl = dyn_cast<ValueDecl>(New)) { 1934 QualType newType = HandleAddressSpaceTypeAttribute(vDecl->getType(), 1935 Attr); 1936 // install the new addr spaced type into the decl 1937 vDecl->setType(newType); 1938 } 1939 break; 1940 case AttributeList::AT_deprecated: 1941 HandleDeprecatedAttribute(New, Attr); 1942 break; 1943 case AttributeList::AT_visibility: 1944 HandleVisibilityAttribute(New, Attr); 1945 break; 1946 case AttributeList::AT_weak: 1947 HandleWeakAttribute(New, Attr); 1948 break; 1949 case AttributeList::AT_dllimport: 1950 HandleDLLImportAttribute(New, Attr); 1951 break; 1952 case AttributeList::AT_dllexport: 1953 HandleDLLExportAttribute(New, Attr); 1954 break; 1955 case AttributeList::AT_nothrow: 1956 HandleNothrowAttribute(New, Attr); 1957 break; 1958 case AttributeList::AT_stdcall: 1959 HandleStdCallAttribute(New, Attr); 1960 break; 1961 case AttributeList::AT_fastcall: 1962 HandleFastCallAttribute(New, Attr); 1963 break; 1964 case AttributeList::AT_aligned: 1965 HandleAlignedAttribute(New, Attr); 1966 break; 1967 case AttributeList::AT_packed: 1968 HandlePackedAttribute(New, Attr); 1969 break; 1970 case AttributeList::AT_annotate: 1971 HandleAnnotateAttribute(New, Attr); 1972 break; 1973 case AttributeList::AT_noreturn: 1974 HandleNoReturnAttribute(New, Attr); 1975 break; 1976 case AttributeList::AT_format: 1977 HandleFormatAttribute(New, Attr); 1978 break; 1979 default: 1980#if 0 1981 // TODO: when we have the full set of attributes, warn about unknown ones. 1982 Diag(Attr->getLoc(), diag::warn_attribute_ignored, 1983 Attr->getName()->getName()); 1984#endif 1985 break; 1986 } 1987} 1988 1989void Sema::HandleDeclAttributes(Decl *New, AttributeList *declspec_prefix, 1990 AttributeList *declarator_postfix) { 1991 while (declspec_prefix) { 1992 HandleDeclAttribute(New, declspec_prefix); 1993 declspec_prefix = declspec_prefix->getNext(); 1994 } 1995 while (declarator_postfix) { 1996 HandleDeclAttribute(New, declarator_postfix); 1997 declarator_postfix = declarator_postfix->getNext(); 1998 } 1999} 2000 2001void Sema::HandleOCUVectorTypeAttribute(TypedefDecl *tDecl, 2002 AttributeList *rawAttr) { 2003 QualType curType = tDecl->getUnderlyingType(); 2004 // check the attribute arguments. 2005 if (rawAttr->getNumArgs() != 1) { 2006 Diag(rawAttr->getLoc(), diag::err_attribute_wrong_number_arguments, 2007 std::string("1")); 2008 return; 2009 } 2010 Expr *sizeExpr = static_cast<Expr *>(rawAttr->getArg(0)); 2011 llvm::APSInt vecSize(32); 2012 if (!sizeExpr->isIntegerConstantExpr(vecSize, Context)) { 2013 Diag(rawAttr->getLoc(), diag::err_attribute_argument_not_int, 2014 "ocu_vector_type", sizeExpr->getSourceRange()); 2015 return; 2016 } 2017 // unlike gcc's vector_size attribute, we do not allow vectors to be defined 2018 // in conjunction with complex types (pointers, arrays, functions, etc.). 2019 Type *canonType = curType.getCanonicalType().getTypePtr(); 2020 if (!(canonType->isIntegerType() || canonType->isRealFloatingType())) { 2021 Diag(rawAttr->getLoc(), diag::err_attribute_invalid_vector_type, 2022 curType.getCanonicalType().getAsString()); 2023 return; 2024 } 2025 // unlike gcc's vector_size attribute, the size is specified as the 2026 // number of elements, not the number of bytes. 2027 unsigned vectorSize = static_cast<unsigned>(vecSize.getZExtValue()); 2028 2029 if (vectorSize == 0) { 2030 Diag(rawAttr->getLoc(), diag::err_attribute_zero_size, 2031 sizeExpr->getSourceRange()); 2032 return; 2033 } 2034 // Instantiate/Install the vector type, the number of elements is > 0. 2035 tDecl->setUnderlyingType(Context.getOCUVectorType(curType, vectorSize)); 2036 // Remember this typedef decl, we will need it later for diagnostics. 2037 OCUVectorDecls.push_back(tDecl); 2038} 2039 2040QualType Sema::HandleVectorTypeAttribute(QualType curType, 2041 AttributeList *rawAttr) { 2042 // check the attribute arugments. 2043 if (rawAttr->getNumArgs() != 1) { 2044 Diag(rawAttr->getLoc(), diag::err_attribute_wrong_number_arguments, 2045 std::string("1")); 2046 return QualType(); 2047 } 2048 Expr *sizeExpr = static_cast<Expr *>(rawAttr->getArg(0)); 2049 llvm::APSInt vecSize(32); 2050 if (!sizeExpr->isIntegerConstantExpr(vecSize, Context)) { 2051 Diag(rawAttr->getLoc(), diag::err_attribute_argument_not_int, 2052 "vector_size", sizeExpr->getSourceRange()); 2053 return QualType(); 2054 } 2055 // navigate to the base type - we need to provide for vector pointers, 2056 // vector arrays, and functions returning vectors. 2057 Type *canonType = curType.getCanonicalType().getTypePtr(); 2058 2059 if (canonType->isPointerType() || canonType->isArrayType() || 2060 canonType->isFunctionType()) { 2061 assert(0 && "HandleVector(): Complex type construction unimplemented"); 2062 /* FIXME: rebuild the type from the inside out, vectorizing the inner type. 2063 do { 2064 if (PointerType *PT = dyn_cast<PointerType>(canonType)) 2065 canonType = PT->getPointeeType().getTypePtr(); 2066 else if (ArrayType *AT = dyn_cast<ArrayType>(canonType)) 2067 canonType = AT->getElementType().getTypePtr(); 2068 else if (FunctionType *FT = dyn_cast<FunctionType>(canonType)) 2069 canonType = FT->getResultType().getTypePtr(); 2070 } while (canonType->isPointerType() || canonType->isArrayType() || 2071 canonType->isFunctionType()); 2072 */ 2073 } 2074 // the base type must be integer or float. 2075 if (!(canonType->isIntegerType() || canonType->isRealFloatingType())) { 2076 Diag(rawAttr->getLoc(), diag::err_attribute_invalid_vector_type, 2077 curType.getCanonicalType().getAsString()); 2078 return QualType(); 2079 } 2080 unsigned typeSize = static_cast<unsigned>(Context.getTypeSize(curType)); 2081 // vecSize is specified in bytes - convert to bits. 2082 unsigned vectorSize = static_cast<unsigned>(vecSize.getZExtValue() * 8); 2083 2084 // the vector size needs to be an integral multiple of the type size. 2085 if (vectorSize % typeSize) { 2086 Diag(rawAttr->getLoc(), diag::err_attribute_invalid_size, 2087 sizeExpr->getSourceRange()); 2088 return QualType(); 2089 } 2090 if (vectorSize == 0) { 2091 Diag(rawAttr->getLoc(), diag::err_attribute_zero_size, 2092 sizeExpr->getSourceRange()); 2093 return QualType(); 2094 } 2095 // Instantiate the vector type, the number of elements is > 0, and not 2096 // required to be a power of 2, unlike GCC. 2097 return Context.getVectorType(curType, vectorSize/typeSize); 2098} 2099 2100void Sema::HandlePackedAttribute(Decl *d, AttributeList *rawAttr) { 2101 // check the attribute arguments. 2102 if (rawAttr->getNumArgs() > 0) { 2103 Diag(rawAttr->getLoc(), diag::err_attribute_wrong_number_arguments, 2104 std::string("0")); 2105 return; 2106 } 2107 2108 if (TagDecl *TD = dyn_cast<TagDecl>(d)) 2109 TD->addAttr(new PackedAttr); 2110 else if (FieldDecl *FD = dyn_cast<FieldDecl>(d)) { 2111 // If the alignment is less than or equal to 8 bits, the packed attribute 2112 // has no effect. 2113 if (Context.getTypeAlign(FD->getType()) <= 8) 2114 Diag(rawAttr->getLoc(), 2115 diag::warn_attribute_ignored_for_field_of_type, 2116 rawAttr->getName()->getName(), FD->getType().getAsString()); 2117 else 2118 FD->addAttr(new PackedAttr); 2119 } else 2120 Diag(rawAttr->getLoc(), diag::warn_attribute_ignored, 2121 rawAttr->getName()->getName()); 2122} 2123 2124void Sema::HandleNoReturnAttribute(Decl *d, AttributeList *rawAttr) { 2125 // check the attribute arguments. 2126 if (rawAttr->getNumArgs() != 0) { 2127 Diag(rawAttr->getLoc(), diag::err_attribute_wrong_number_arguments, 2128 std::string("0")); 2129 return; 2130 } 2131 2132 FunctionDecl *Fn = dyn_cast<FunctionDecl>(d); 2133 2134 if (!Fn) { 2135 Diag(rawAttr->getLoc(), diag::warn_attribute_wrong_decl_type, 2136 "noreturn", "function"); 2137 return; 2138 } 2139 2140 d->addAttr(new NoReturnAttr()); 2141} 2142 2143void Sema::HandleDeprecatedAttribute(Decl *d, AttributeList *rawAttr) { 2144 // check the attribute arguments. 2145 if (rawAttr->getNumArgs() != 0) { 2146 Diag(rawAttr->getLoc(), diag::err_attribute_wrong_number_arguments, 2147 std::string("0")); 2148 return; 2149 } 2150 2151 d->addAttr(new DeprecatedAttr()); 2152} 2153 2154void Sema::HandleVisibilityAttribute(Decl *d, AttributeList *rawAttr) { 2155 // check the attribute arguments. 2156 if (rawAttr->getNumArgs() != 1) { 2157 Diag(rawAttr->getLoc(), diag::err_attribute_wrong_number_arguments, 2158 std::string("1")); 2159 return; 2160 } 2161 2162 Expr *Arg = static_cast<Expr*>(rawAttr->getArg(0)); 2163 Arg = Arg->IgnoreParenCasts(); 2164 StringLiteral *Str = dyn_cast<StringLiteral>(Arg); 2165 2166 if (Str == 0 || Str->isWide()) { 2167 Diag(rawAttr->getLoc(), diag::err_attribute_argument_n_not_string, 2168 "visibility", std::string("1")); 2169 return; 2170 } 2171 2172 const char *TypeStr = Str->getStrData(); 2173 unsigned TypeLen = Str->getByteLength(); 2174 llvm::GlobalValue::VisibilityTypes type; 2175 2176 if (TypeLen == 7 && !memcmp(TypeStr, "default", 7)) 2177 type = llvm::GlobalValue::DefaultVisibility; 2178 else if (TypeLen == 6 && !memcmp(TypeStr, "hidden", 6)) 2179 type = llvm::GlobalValue::HiddenVisibility; 2180 else if (TypeLen == 8 && !memcmp(TypeStr, "internal", 8)) 2181 type = llvm::GlobalValue::HiddenVisibility; // FIXME 2182 else if (TypeLen == 9 && !memcmp(TypeStr, "protected", 9)) 2183 type = llvm::GlobalValue::ProtectedVisibility; 2184 else { 2185 Diag(rawAttr->getLoc(), diag::warn_attribute_type_not_supported, 2186 "visibility", TypeStr); 2187 return; 2188 } 2189 2190 d->addAttr(new VisibilityAttr(type)); 2191} 2192 2193void Sema::HandleWeakAttribute(Decl *d, AttributeList *rawAttr) { 2194 // check the attribute arguments. 2195 if (rawAttr->getNumArgs() != 0) { 2196 Diag(rawAttr->getLoc(), diag::err_attribute_wrong_number_arguments, 2197 std::string("0")); 2198 return; 2199 } 2200 2201 d->addAttr(new WeakAttr()); 2202} 2203 2204void Sema::HandleDLLImportAttribute(Decl *d, AttributeList *rawAttr) { 2205 // check the attribute arguments. 2206 if (rawAttr->getNumArgs() != 0) { 2207 Diag(rawAttr->getLoc(), diag::err_attribute_wrong_number_arguments, 2208 std::string("0")); 2209 return; 2210 } 2211 2212 d->addAttr(new DLLImportAttr()); 2213} 2214 2215void Sema::HandleDLLExportAttribute(Decl *d, AttributeList *rawAttr) { 2216 // check the attribute arguments. 2217 if (rawAttr->getNumArgs() != 0) { 2218 Diag(rawAttr->getLoc(), diag::err_attribute_wrong_number_arguments, 2219 std::string("0")); 2220 return; 2221 } 2222 2223 d->addAttr(new DLLExportAttr()); 2224} 2225 2226void Sema::HandleStdCallAttribute(Decl *d, AttributeList *rawAttr) { 2227 // check the attribute arguments. 2228 if (rawAttr->getNumArgs() != 0) { 2229 Diag(rawAttr->getLoc(), diag::err_attribute_wrong_number_arguments, 2230 std::string("0")); 2231 return; 2232 } 2233 2234 d->addAttr(new StdCallAttr()); 2235} 2236 2237void Sema::HandleFastCallAttribute(Decl *d, AttributeList *rawAttr) { 2238 // check the attribute arguments. 2239 if (rawAttr->getNumArgs() != 0) { 2240 Diag(rawAttr->getLoc(), diag::err_attribute_wrong_number_arguments, 2241 std::string("0")); 2242 return; 2243 } 2244 2245 d->addAttr(new FastCallAttr()); 2246} 2247 2248void Sema::HandleNothrowAttribute(Decl *d, AttributeList *rawAttr) { 2249 // check the attribute arguments. 2250 if (rawAttr->getNumArgs() != 0) { 2251 Diag(rawAttr->getLoc(), diag::err_attribute_wrong_number_arguments, 2252 std::string("0")); 2253 return; 2254 } 2255 2256 d->addAttr(new NoThrowAttr()); 2257} 2258 2259static const FunctionTypeProto *getFunctionProto(Decl *d) { 2260 ValueDecl *decl = dyn_cast<ValueDecl>(d); 2261 if (!decl) return 0; 2262 2263 QualType Ty = decl->getType(); 2264 2265 if (Ty->isFunctionPointerType()) { 2266 const PointerType *PtrTy = Ty->getAsPointerType(); 2267 Ty = PtrTy->getPointeeType(); 2268 } 2269 2270 if (const FunctionType *FnTy = Ty->getAsFunctionType()) 2271 return dyn_cast<FunctionTypeProto>(FnTy->getAsFunctionType()); 2272 2273 return 0; 2274} 2275 2276 2277/// Handle __attribute__((format(type,idx,firstarg))) attributes 2278/// based on http://gcc.gnu.org/onlinedocs/gcc/Function-Attributes.html 2279void Sema::HandleFormatAttribute(Decl *d, AttributeList *rawAttr) { 2280 2281 if (!rawAttr->getParameterName()) { 2282 Diag(rawAttr->getLoc(), diag::err_attribute_argument_n_not_string, 2283 "format", std::string("1")); 2284 return; 2285 } 2286 2287 if (rawAttr->getNumArgs() != 2) { 2288 Diag(rawAttr->getLoc(), diag::err_attribute_wrong_number_arguments, 2289 std::string("3")); 2290 return; 2291 } 2292 2293 // GCC ignores the format attribute on K&R style function 2294 // prototypes, so we ignore it as well 2295 const FunctionTypeProto *proto = getFunctionProto(d); 2296 2297 if (!proto) { 2298 Diag(rawAttr->getLoc(), diag::warn_attribute_wrong_decl_type, 2299 "format", "function"); 2300 return; 2301 } 2302 2303 // FIXME: in C++ the implicit 'this' function parameter also counts. 2304 // this is needed in order to be compatible with GCC 2305 // the index must start in 1 and the limit is numargs+1 2306 unsigned NumArgs = proto->getNumArgs(); 2307 unsigned FirstIdx = 1; 2308 2309 const char *Format = rawAttr->getParameterName()->getName(); 2310 unsigned FormatLen = rawAttr->getParameterName()->getLength(); 2311 2312 // Normalize the argument, __foo__ becomes foo. 2313 if (FormatLen > 4 && Format[0] == '_' && Format[1] == '_' && 2314 Format[FormatLen - 2] == '_' && Format[FormatLen - 1] == '_') { 2315 Format += 2; 2316 FormatLen -= 4; 2317 } 2318 2319 if (!((FormatLen == 5 && !memcmp(Format, "scanf", 5)) 2320 || (FormatLen == 6 && !memcmp(Format, "printf", 6)) 2321 || (FormatLen == 7 && !memcmp(Format, "strfmon", 7)) 2322 || (FormatLen == 8 && !memcmp(Format, "strftime", 8)))) { 2323 Diag(rawAttr->getLoc(), diag::warn_attribute_type_not_supported, 2324 "format", rawAttr->getParameterName()->getName()); 2325 return; 2326 } 2327 2328 // checks for the 2nd argument 2329 Expr *IdxExpr = static_cast<Expr *>(rawAttr->getArg(0)); 2330 llvm::APSInt Idx(Context.getTypeSize(IdxExpr->getType())); 2331 if (!IdxExpr->isIntegerConstantExpr(Idx, Context)) { 2332 Diag(rawAttr->getLoc(), diag::err_attribute_argument_n_not_int, 2333 "format", std::string("2"), IdxExpr->getSourceRange()); 2334 return; 2335 } 2336 2337 if (Idx.getZExtValue() < FirstIdx || Idx.getZExtValue() > NumArgs) { 2338 Diag(rawAttr->getLoc(), diag::err_attribute_argument_out_of_bounds, 2339 "format", std::string("2"), IdxExpr->getSourceRange()); 2340 return; 2341 } 2342 2343 // make sure the format string is really a string 2344 QualType Ty = proto->getArgType(Idx.getZExtValue()-1); 2345 if (!Ty->isPointerType() || 2346 !Ty->getAsPointerType()->getPointeeType()->isCharType()) { 2347 Diag(rawAttr->getLoc(), diag::err_format_attribute_not_string, 2348 IdxExpr->getSourceRange()); 2349 return; 2350 } 2351 2352 2353 // check the 3rd argument 2354 Expr *FirstArgExpr = static_cast<Expr *>(rawAttr->getArg(1)); 2355 llvm::APSInt FirstArg(Context.getTypeSize(FirstArgExpr->getType())); 2356 if (!FirstArgExpr->isIntegerConstantExpr(FirstArg, Context)) { 2357 Diag(rawAttr->getLoc(), diag::err_attribute_argument_n_not_int, 2358 "format", std::string("3"), FirstArgExpr->getSourceRange()); 2359 return; 2360 } 2361 2362 // check if the function is variadic if the 3rd argument non-zero 2363 if (FirstArg != 0) { 2364 if (proto->isVariadic()) { 2365 ++NumArgs; // +1 for ... 2366 } else { 2367 Diag(d->getLocation(), diag::err_format_attribute_requires_variadic); 2368 return; 2369 } 2370 } 2371 2372 // strftime requires FirstArg to be 0 because it doesn't read from any variable 2373 // the input is just the current time + the format string 2374 if (FormatLen == 8 && !memcmp(Format, "strftime", 8)) { 2375 if (FirstArg != 0) { 2376 Diag(rawAttr->getLoc(), diag::err_format_strftime_third_parameter, 2377 FirstArgExpr->getSourceRange()); 2378 return; 2379 } 2380 // if 0 it disables parameter checking (to use with e.g. va_list) 2381 } else if (FirstArg != 0 && FirstArg != NumArgs) { 2382 Diag(rawAttr->getLoc(), diag::err_attribute_argument_out_of_bounds, 2383 "format", std::string("3"), FirstArgExpr->getSourceRange()); 2384 return; 2385 } 2386 2387 d->addAttr(new FormatAttr(std::string(Format, FormatLen), 2388 Idx.getZExtValue(), FirstArg.getZExtValue())); 2389} 2390 2391void Sema::HandleAnnotateAttribute(Decl *d, AttributeList *rawAttr) { 2392 // check the attribute arguments. 2393 if (rawAttr->getNumArgs() != 1) { 2394 Diag(rawAttr->getLoc(), diag::err_attribute_wrong_number_arguments, 2395 std::string("1")); 2396 return; 2397 } 2398 Expr *argExpr = static_cast<Expr *>(rawAttr->getArg(0)); 2399 StringLiteral *SE = dyn_cast<StringLiteral>(argExpr); 2400 2401 // Make sure that there is a string literal as the annotation's single 2402 // argument. 2403 if (!SE) { 2404 Diag(rawAttr->getLoc(), diag::err_attribute_annotate_no_string); 2405 return; 2406 } 2407 d->addAttr(new AnnotateAttr(std::string(SE->getStrData(), 2408 SE->getByteLength()))); 2409} 2410 2411void Sema::HandleAlignedAttribute(Decl *d, AttributeList *rawAttr) 2412{ 2413 // check the attribute arguments. 2414 if (rawAttr->getNumArgs() > 1) { 2415 Diag(rawAttr->getLoc(), diag::err_attribute_wrong_number_arguments, 2416 std::string("1")); 2417 return; 2418 } 2419 2420 unsigned Align = 0; 2421 2422 if (rawAttr->getNumArgs() == 0) { 2423 // FIXME: This should be the target specific maximum alignment. 2424 // (For now we just use 128 bits which is the maximum on X86. 2425 Align = 128; 2426 return; 2427 } else { 2428 Expr *alignmentExpr = static_cast<Expr *>(rawAttr->getArg(0)); 2429 llvm::APSInt alignment(32); 2430 if (!alignmentExpr->isIntegerConstantExpr(alignment, Context)) { 2431 Diag(rawAttr->getLoc(), diag::err_attribute_argument_not_int, 2432 "aligned", alignmentExpr->getSourceRange()); 2433 return; 2434 } 2435 2436 Align = alignment.getZExtValue() * 8; 2437 } 2438 2439 d->addAttr(new AlignedAttr(Align)); 2440} 2441