SemaDecl.cpp revision 248a753f6b670692523c99afaeb8fe98f7ae3ca7
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) || 39 isa<ObjCInterfaceDecl>(IIDecl) || 40 isa<TagDecl>(IIDecl))) 41 return IIDecl; 42 return 0; 43} 44 45void Sema::PushDeclContext(DeclContext *CD) { 46 assert(CD->getParent() == CurContext && 47 "The next DeclContext should be directly contained in the current one."); 48 CurContext = CD; 49} 50 51void Sema::PopDeclContext() { 52 assert(CurContext && "DeclContext imbalance!"); 53 CurContext = CurContext->getParent(); 54} 55 56/// Add this decl to the scope shadowed decl chains. 57void Sema::PushOnScopeChains(NamedDecl *D, Scope *S) { 58 IdResolver.AddDecl(D, S); 59 S->AddDecl(D); 60} 61 62void Sema::ActOnPopScope(SourceLocation Loc, Scope *S) { 63 if (S->decl_empty()) return; 64 assert((S->getFlags() & Scope::DeclScope) &&"Scope shouldn't contain decls!"); 65 66 for (Scope::decl_iterator I = S->decl_begin(), E = S->decl_end(); 67 I != E; ++I) { 68 Decl *TmpD = static_cast<Decl*>(*I); 69 assert(TmpD && "This decl didn't get pushed??"); 70 ScopedDecl *D = dyn_cast<ScopedDecl>(TmpD); 71 assert(D && "This decl isn't a ScopedDecl?"); 72 73 IdentifierInfo *II = D->getIdentifier(); 74 if (!II) continue; 75 76 // Unlink this decl from the identifier. 77 IdResolver.RemoveDecl(D); 78 79 // This will have to be revisited for C++: there we want to nest stuff in 80 // namespace decls etc. Even for C, we might want a top-level translation 81 // unit decl or something. 82 if (!CurFunctionDecl) 83 continue; 84 85 // Chain this decl to the containing function, it now owns the memory for 86 // the decl. 87 D->setNext(CurFunctionDecl->getDeclChain()); 88 CurFunctionDecl->setDeclChain(D); 89 } 90} 91 92/// getObjCInterfaceDecl - Look up a for a class declaration in the scope. 93/// return 0 if one not found. 94ObjCInterfaceDecl *Sema::getObjCInterfaceDecl(IdentifierInfo *Id) { 95 // The third "scope" argument is 0 since we aren't enabling lazy built-in 96 // creation from this context. 97 Decl *IDecl = LookupDecl(Id, Decl::IDNS_Ordinary, 0, false); 98 99 return dyn_cast_or_null<ObjCInterfaceDecl>(IDecl); 100} 101 102/// LookupDecl - Look up the inner-most declaration in the specified 103/// namespace. 104Decl *Sema::LookupDecl(const IdentifierInfo *II, unsigned NSI, 105 Scope *S, bool enableLazyBuiltinCreation) { 106 if (II == 0) return 0; 107 unsigned NS = NSI; 108 if (getLangOptions().CPlusPlus && (NS & Decl::IDNS_Ordinary)) 109 NS |= Decl::IDNS_Tag; 110 111 // Scan up the scope chain looking for a decl that matches this identifier 112 // that is in the appropriate namespace. This search should not take long, as 113 // shadowing of names is uncommon, and deep shadowing is extremely uncommon. 114 NamedDecl *ND = IdResolver.Lookup(II, NS); 115 if (ND) return ND; 116 117 // If we didn't find a use of this identifier, and if the identifier 118 // corresponds to a compiler builtin, create the decl object for the builtin 119 // now, injecting it into translation unit scope, and return it. 120 if (NS & Decl::IDNS_Ordinary) { 121 if (enableLazyBuiltinCreation) { 122 // If this is a builtin on this (or all) targets, create the decl. 123 if (unsigned BuiltinID = II->getBuiltinID()) 124 return LazilyCreateBuiltin((IdentifierInfo *)II, BuiltinID, S); 125 } 126 if (getLangOptions().ObjC1) { 127 // @interface and @compatibility_alias introduce typedef-like names. 128 // Unlike typedef's, they can only be introduced at file-scope (and are 129 // therefore not scoped decls). They can, however, be shadowed by 130 // other names in IDNS_Ordinary. 131 ObjCInterfaceDeclsTy::iterator IDI = ObjCInterfaceDecls.find(II); 132 if (IDI != ObjCInterfaceDecls.end()) 133 return IDI->second; 134 ObjCAliasTy::iterator I = ObjCAliasDecls.find(II); 135 if (I != ObjCAliasDecls.end()) 136 return I->second->getClassInterface(); 137 } 138 } 139 return 0; 140} 141 142void Sema::InitBuiltinVaListType() 143{ 144 if (!Context.getBuiltinVaListType().isNull()) 145 return; 146 147 IdentifierInfo *VaIdent = &Context.Idents.get("__builtin_va_list"); 148 Decl *VaDecl = LookupDecl(VaIdent, Decl::IDNS_Ordinary, TUScope); 149 TypedefDecl *VaTypedef = cast<TypedefDecl>(VaDecl); 150 Context.setBuiltinVaListType(Context.getTypedefType(VaTypedef)); 151} 152 153/// LazilyCreateBuiltin - The specified Builtin-ID was first used at file scope. 154/// lazily create a decl for it. 155ScopedDecl *Sema::LazilyCreateBuiltin(IdentifierInfo *II, unsigned bid, 156 Scope *S) { 157 Builtin::ID BID = (Builtin::ID)bid; 158 159 if (BID == Builtin::BI__builtin_va_start || 160 BID == Builtin::BI__builtin_va_copy || 161 BID == Builtin::BI__builtin_va_end) 162 InitBuiltinVaListType(); 163 164 QualType R = Context.BuiltinInfo.GetBuiltinType(BID, Context); 165 FunctionDecl *New = FunctionDecl::Create(Context, CurContext, 166 SourceLocation(), II, R, 167 FunctionDecl::Extern, false, 0); 168 169 // TUScope is the translation-unit scope to insert this function into. 170 TUScope->AddDecl(New); 171 172 // Add this decl to the end of the identifier info. 173 IdResolver.AddGlobalDecl(New); 174 175 return New; 176} 177 178/// MergeTypeDefDecl - We just parsed a typedef 'New' which has the same name 179/// and scope as a previous declaration 'Old'. Figure out how to resolve this 180/// situation, merging decls or emitting diagnostics as appropriate. 181/// 182TypedefDecl *Sema::MergeTypeDefDecl(TypedefDecl *New, Decl *OldD) { 183 // Verify the old decl was also a typedef. 184 TypedefDecl *Old = dyn_cast<TypedefDecl>(OldD); 185 if (!Old) { 186 Diag(New->getLocation(), diag::err_redefinition_different_kind, 187 New->getName()); 188 Diag(OldD->getLocation(), diag::err_previous_definition); 189 return New; 190 } 191 192 // Allow multiple definitions for ObjC built-in typedefs. 193 // FIXME: Verify the underlying types are equivalent! 194 if (getLangOptions().ObjC1 && isBuiltinObjCType(New)) 195 return Old; 196 197 // Redeclaration of a type is a constraint violation (6.7.2.3p1). 198 // Apparently GCC, Intel, and Sun all silently ignore the redeclaration if 199 // *either* declaration is in a system header. The code below implements 200 // this adhoc compatibility rule. FIXME: The following code will not 201 // work properly when compiling ".i" files (containing preprocessed output). 202 SourceManager &SrcMgr = Context.getSourceManager(); 203 const FileEntry *OldDeclFile = SrcMgr.getFileEntryForLoc(Old->getLocation()); 204 const FileEntry *NewDeclFile = SrcMgr.getFileEntryForLoc(New->getLocation()); 205 HeaderSearch &HdrInfo = PP.getHeaderSearchInfo(); 206 DirectoryLookup::DirType OldDirType = HdrInfo.getFileDirFlavor(OldDeclFile); 207 DirectoryLookup::DirType NewDirType = HdrInfo.getFileDirFlavor(NewDeclFile); 208 209 // Allow reclarations in both SystemHeaderDir and ExternCSystemHeaderDir. 210 if ((OldDirType != DirectoryLookup::NormalHeaderDir || 211 NewDirType != DirectoryLookup::NormalHeaderDir) || 212 getLangOptions().Microsoft) 213 return New; 214 215 // TODO: CHECK FOR CONFLICTS, multiple decls with same name in one scope. 216 // TODO: This is totally simplistic. It should handle merging functions 217 // together etc, merging extern int X; int X; ... 218 Diag(New->getLocation(), diag::err_redefinition, New->getName()); 219 Diag(Old->getLocation(), diag::err_previous_definition); 220 return New; 221} 222 223/// DeclhasAttr - returns true if decl Declaration already has the target attribute. 224static bool DeclHasAttr(const Decl *decl, const Attr *target) { 225 for (const Attr *attr = decl->getAttrs(); attr; attr = attr->getNext()) 226 if (attr->getKind() == target->getKind()) 227 return true; 228 229 return false; 230} 231 232/// MergeAttributes - append attributes from the Old decl to the New one. 233static void MergeAttributes(Decl *New, Decl *Old) { 234 Attr *attr = const_cast<Attr*>(Old->getAttrs()), *tmp; 235 236// FIXME: fix this code to cleanup the Old attrs correctly 237 while (attr) { 238 tmp = attr; 239 attr = attr->getNext(); 240 241 if (!DeclHasAttr(New, tmp)) { 242 New->addAttr(tmp); 243 } else { 244 tmp->setNext(0); 245 delete(tmp); 246 } 247 } 248} 249 250/// MergeFunctionDecl - We just parsed a function 'New' from 251/// declarator D which has the same name and scope as a previous 252/// declaration 'Old'. Figure out how to resolve this situation, 253/// merging decls or emitting diagnostics as appropriate. 254/// 255FunctionDecl *Sema::MergeFunctionDecl(FunctionDecl *New, Decl *OldD) { 256 // Verify the old decl was also a function. 257 FunctionDecl *Old = dyn_cast<FunctionDecl>(OldD); 258 if (!Old) { 259 Diag(New->getLocation(), diag::err_redefinition_different_kind, 260 New->getName()); 261 Diag(OldD->getLocation(), diag::err_previous_definition); 262 return New; 263 } 264 265 MergeAttributes(New, Old); 266 267 QualType OldQType = Context.getCanonicalType(Old->getType()); 268 QualType NewQType = Context.getCanonicalType(New->getType()); 269 270 // C++ [dcl.fct]p3: 271 // All declarations for a function shall agree exactly in both the 272 // return type and the parameter-type-list. 273 if (getLangOptions().CPlusPlus && OldQType == NewQType) 274 return MergeCXXFunctionDecl(New, Old); 275 276 // C: Function types need to be compatible, not identical. This handles 277 // duplicate function decls like "void f(int); void f(enum X);" properly. 278 if (!getLangOptions().CPlusPlus && 279 Context.functionTypesAreCompatible(OldQType, NewQType)) { 280 return New; 281 } 282 283 // A function that has already been declared has been redeclared or defined 284 // with a different type- show appropriate diagnostic 285 diag::kind PrevDiag; 286 if (Old->getBody()) 287 PrevDiag = diag::err_previous_definition; 288 else if (Old->isImplicit()) 289 PrevDiag = diag::err_previous_implicit_declaration; 290 else 291 PrevDiag = diag::err_previous_declaration; 292 293 // TODO: CHECK FOR CONFLICTS, multiple decls with same name in one scope. 294 // TODO: This is totally simplistic. It should handle merging functions 295 // together etc, merging extern int X; int X; ... 296 Diag(New->getLocation(), diag::err_conflicting_types, New->getName()); 297 Diag(Old->getLocation(), PrevDiag); 298 return New; 299} 300 301/// equivalentArrayTypes - Used to determine whether two array types are 302/// equivalent. 303/// We need to check this explicitly as an incomplete array definition is 304/// considered a VariableArrayType, so will not match a complete array 305/// definition that would be otherwise equivalent. 306static bool areEquivalentArrayTypes(QualType NewQType, QualType OldQType) { 307 const ArrayType *NewAT = NewQType->getAsArrayType(); 308 const ArrayType *OldAT = OldQType->getAsArrayType(); 309 310 if (!NewAT || !OldAT) 311 return false; 312 313 // If either (or both) array types in incomplete we need to strip off the 314 // outer VariableArrayType. Once the outer VAT is removed the remaining 315 // types must be identical if the array types are to be considered 316 // equivalent. 317 // eg. int[][1] and int[1][1] become 318 // VAT(null, CAT(1, int)) and CAT(1, CAT(1, int)) 319 // removing the outermost VAT gives 320 // CAT(1, int) and CAT(1, int) 321 // which are equal, therefore the array types are equivalent. 322 if (NewAT->isIncompleteArrayType() || OldAT->isIncompleteArrayType()) { 323 if (NewAT->getIndexTypeQualifier() != OldAT->getIndexTypeQualifier()) 324 return false; 325 NewQType = NewAT->getElementType().getCanonicalType(); 326 OldQType = OldAT->getElementType().getCanonicalType(); 327 } 328 329 return NewQType == OldQType; 330} 331 332/// MergeVarDecl - We just parsed a variable 'New' which has the same name 333/// and scope as a previous declaration 'Old'. Figure out how to resolve this 334/// situation, merging decls or emitting diagnostics as appropriate. 335/// 336/// FIXME: Need to carefully consider tentative definition rules (C99 6.9.2p2). 337/// For example, we incorrectly complain about i1, i4 from C99 6.9.2p4. 338/// 339VarDecl *Sema::MergeVarDecl(VarDecl *New, Decl *OldD) { 340 // Verify the old decl was also a variable. 341 VarDecl *Old = dyn_cast<VarDecl>(OldD); 342 if (!Old) { 343 Diag(New->getLocation(), diag::err_redefinition_different_kind, 344 New->getName()); 345 Diag(OldD->getLocation(), diag::err_previous_definition); 346 return New; 347 } 348 349 MergeAttributes(New, Old); 350 351 // Verify the types match. 352 QualType OldCType = Context.getCanonicalType(Old->getType()); 353 QualType NewCType = Context.getCanonicalType(New->getType()); 354 if (OldCType != NewCType && !areEquivalentArrayTypes(NewCType, OldCType)) { 355 Diag(New->getLocation(), diag::err_redefinition, New->getName()); 356 Diag(Old->getLocation(), diag::err_previous_definition); 357 return New; 358 } 359 // C99 6.2.2p4: Check if we have a static decl followed by a non-static. 360 if (New->getStorageClass() == VarDecl::Static && 361 (Old->getStorageClass() == VarDecl::None || 362 Old->getStorageClass() == VarDecl::Extern)) { 363 Diag(New->getLocation(), diag::err_static_non_static, New->getName()); 364 Diag(Old->getLocation(), diag::err_previous_definition); 365 return New; 366 } 367 // C99 6.2.2p4: Check if we have a non-static decl followed by a static. 368 if (New->getStorageClass() != VarDecl::Static && 369 Old->getStorageClass() == VarDecl::Static) { 370 Diag(New->getLocation(), diag::err_non_static_static, New->getName()); 371 Diag(Old->getLocation(), diag::err_previous_definition); 372 return New; 373 } 374 // We've verified the types match, now handle "tentative" definitions. 375 if (Old->isFileVarDecl() && New->isFileVarDecl()) { 376 // Handle C "tentative" external object definitions (C99 6.9.2). 377 bool OldIsTentative = false; 378 bool NewIsTentative = false; 379 380 if (!Old->getInit() && 381 (Old->getStorageClass() == VarDecl::None || 382 Old->getStorageClass() == VarDecl::Static)) 383 OldIsTentative = true; 384 385 // FIXME: this check doesn't work (since the initializer hasn't been 386 // attached yet). This check should be moved to FinalizeDeclaratorGroup. 387 // Unfortunately, by the time we get to FinializeDeclaratorGroup, we've 388 // thrown out the old decl. 389 if (!New->getInit() && 390 (New->getStorageClass() == VarDecl::None || 391 New->getStorageClass() == VarDecl::Static)) 392 ; // change to NewIsTentative = true; once the code is moved. 393 394 if (NewIsTentative || OldIsTentative) 395 return New; 396 } 397 if (Old->getStorageClass() != VarDecl::Extern && 398 New->getStorageClass() != VarDecl::Extern) { 399 Diag(New->getLocation(), diag::err_redefinition, New->getName()); 400 Diag(Old->getLocation(), diag::err_previous_definition); 401 } 402 return New; 403} 404 405/// CheckParmsForFunctionDef - Check that the parameters of the given 406/// function are appropriate for the definition of a function. This 407/// takes care of any checks that cannot be performed on the 408/// declaration itself, e.g., that the types of each of the function 409/// parameters are complete. 410bool Sema::CheckParmsForFunctionDef(FunctionDecl *FD) { 411 bool HasInvalidParm = false; 412 for (unsigned p = 0, NumParams = FD->getNumParams(); p < NumParams; ++p) { 413 ParmVarDecl *Param = FD->getParamDecl(p); 414 415 // C99 6.7.5.3p4: the parameters in a parameter type list in a 416 // function declarator that is part of a function definition of 417 // that function shall not have incomplete type. 418 if (Param->getType()->isIncompleteType() && 419 !Param->isInvalidDecl()) { 420 Diag(Param->getLocation(), diag::err_typecheck_decl_incomplete_type, 421 Param->getType().getAsString()); 422 Param->setInvalidDecl(); 423 HasInvalidParm = true; 424 } 425 } 426 427 return HasInvalidParm; 428} 429 430/// CreateImplicitParameter - Creates an implicit function parameter 431/// in the scope S and with the given type. This routine is used, for 432/// example, to create the implicit "self" parameter in an Objective-C 433/// method. 434ParmVarDecl * 435Sema::CreateImplicitParameter(Scope *S, IdentifierInfo *Id, 436 SourceLocation IdLoc, QualType Type) { 437 ParmVarDecl *New = ParmVarDecl::Create(Context, CurContext, IdLoc, Id, Type, 438 VarDecl::None, 0, 0); 439 if (Id) 440 PushOnScopeChains(New, S); 441 442 return New; 443} 444 445/// ParsedFreeStandingDeclSpec - This method is invoked when a declspec with 446/// no declarator (e.g. "struct foo;") is parsed. 447Sema::DeclTy *Sema::ParsedFreeStandingDeclSpec(Scope *S, DeclSpec &DS) { 448 // TODO: emit error on 'int;' or 'const enum foo;'. 449 // TODO: emit error on 'typedef int;' 450 // if (!DS.isMissingDeclaratorOk()) Diag(...); 451 452 return dyn_cast_or_null<TagDecl>(static_cast<Decl *>(DS.getTypeRep())); 453} 454 455bool Sema::CheckSingleInitializer(Expr *&Init, QualType DeclType) { 456 // Get the type before calling CheckSingleAssignmentConstraints(), since 457 // it can promote the expression. 458 QualType InitType = Init->getType(); 459 460 AssignConvertType ConvTy = CheckSingleAssignmentConstraints(DeclType, Init); 461 return DiagnoseAssignmentResult(ConvTy, Init->getLocStart(), DeclType, 462 InitType, Init, "initializing"); 463} 464 465bool Sema::CheckInitExpr(Expr *expr, InitListExpr *IList, unsigned slot, 466 QualType ElementType) { 467 Expr *savExpr = expr; // Might be promoted by CheckSingleInitializer. 468 if (CheckSingleInitializer(expr, ElementType)) 469 return true; // types weren't compatible. 470 471 if (savExpr != expr) // The type was promoted, update initializer list. 472 IList->setInit(slot, expr); 473 return false; 474} 475 476bool Sema::CheckStringLiteralInit(StringLiteral *strLiteral, QualType &DeclT) { 477 if (const IncompleteArrayType *IAT = DeclT->getAsIncompleteArrayType()) { 478 // C99 6.7.8p14. We have an array of character type with unknown size 479 // being initialized to a string literal. 480 llvm::APSInt ConstVal(32); 481 ConstVal = strLiteral->getByteLength() + 1; 482 // Return a new array type (C99 6.7.8p22). 483 DeclT = Context.getConstantArrayType(IAT->getElementType(), ConstVal, 484 ArrayType::Normal, 0); 485 } else if (const ConstantArrayType *CAT = DeclT->getAsConstantArrayType()) { 486 // C99 6.7.8p14. We have an array of character type with known size. 487 if (strLiteral->getByteLength() > (unsigned)CAT->getMaximumElements()) 488 Diag(strLiteral->getSourceRange().getBegin(), 489 diag::warn_initializer_string_for_char_array_too_long, 490 strLiteral->getSourceRange()); 491 } else { 492 assert(0 && "HandleStringLiteralInit(): Invalid array type"); 493 } 494 // Set type from "char *" to "constant array of char". 495 strLiteral->setType(DeclT); 496 // For now, we always return false (meaning success). 497 return false; 498} 499 500StringLiteral *Sema::IsStringLiteralInit(Expr *Init, QualType DeclType) { 501 const ArrayType *AT = DeclType->getAsArrayType(); 502 if (AT && AT->getElementType()->isCharType()) { 503 return dyn_cast<StringLiteral>(Init); 504 } 505 return 0; 506} 507 508// CheckInitializerListTypes - Checks the types of elements of an initializer 509// list. This function is recursive: it calls itself to initialize subelements 510// of aggregate types. Note that the topLevel parameter essentially refers to 511// whether this expression "owns" the initializer list passed in, or if this 512// initialization is taking elements out of a parent initializer. Each 513// call to this function adds zero or more to startIndex, reports any errors, 514// and returns true if it found any inconsistent types. 515bool Sema::CheckInitializerListTypes(InitListExpr*& IList, QualType &DeclType, 516 bool topLevel, unsigned& startIndex) { 517 bool hadError = false; 518 519 if (DeclType->isScalarType()) { 520 // The simplest case: initializing a single scalar 521 if (topLevel) { 522 Diag(IList->getLocStart(), diag::warn_braces_around_scalar_init, 523 IList->getSourceRange()); 524 } 525 if (startIndex < IList->getNumInits()) { 526 Expr* expr = IList->getInit(startIndex); 527 if (InitListExpr *SubInitList = dyn_cast<InitListExpr>(expr)) { 528 // FIXME: Should an error be reported here instead? 529 unsigned newIndex = 0; 530 CheckInitializerListTypes(SubInitList, DeclType, true, newIndex); 531 } else { 532 hadError |= CheckInitExpr(expr, IList, startIndex, DeclType); 533 } 534 ++startIndex; 535 } 536 // FIXME: Should an error be reported for empty initializer list + scalar? 537 } else if (DeclType->isVectorType()) { 538 if (startIndex < IList->getNumInits()) { 539 const VectorType *VT = DeclType->getAsVectorType(); 540 int maxElements = VT->getNumElements(); 541 QualType elementType = VT->getElementType(); 542 543 for (int i = 0; i < maxElements; ++i) { 544 // Don't attempt to go past the end of the init list 545 if (startIndex >= IList->getNumInits()) 546 break; 547 Expr* expr = IList->getInit(startIndex); 548 if (InitListExpr *SubInitList = dyn_cast<InitListExpr>(expr)) { 549 unsigned newIndex = 0; 550 hadError |= CheckInitializerListTypes(SubInitList, elementType, 551 true, newIndex); 552 ++startIndex; 553 } else { 554 hadError |= CheckInitializerListTypes(IList, elementType, 555 false, startIndex); 556 } 557 } 558 } 559 } else if (DeclType->isAggregateType() || DeclType->isUnionType()) { 560 if (DeclType->isStructureType() || DeclType->isUnionType()) { 561 if (startIndex < IList->getNumInits() && !topLevel && 562 Context.typesAreCompatible(IList->getInit(startIndex)->getType(), 563 DeclType)) { 564 // We found a compatible struct; per the standard, this initializes the 565 // struct. (The C standard technically says that this only applies for 566 // initializers for declarations with automatic scope; however, this 567 // construct is unambiguous anyway because a struct cannot contain 568 // a type compatible with itself. We'll output an error when we check 569 // if the initializer is constant.) 570 // FIXME: Is a call to CheckSingleInitializer required here? 571 ++startIndex; 572 } else { 573 RecordDecl* structDecl = DeclType->getAsRecordType()->getDecl(); 574 575 // If the record is invalid, some of it's members are invalid. To avoid 576 // confusion, we forgo checking the intializer for the entire record. 577 if (structDecl->isInvalidDecl()) 578 return true; 579 580 // If structDecl is a forward declaration, this loop won't do anything; 581 // That's okay, because an error should get printed out elsewhere. It 582 // might be worthwhile to skip over the rest of the initializer, though. 583 int numMembers = structDecl->getNumMembers() - 584 structDecl->hasFlexibleArrayMember(); 585 for (int i = 0; i < numMembers; i++) { 586 // Don't attempt to go past the end of the init list 587 if (startIndex >= IList->getNumInits()) 588 break; 589 FieldDecl * curField = structDecl->getMember(i); 590 if (!curField->getIdentifier()) { 591 // Don't initialize unnamed fields, e.g. "int : 20;" 592 continue; 593 } 594 QualType fieldType = curField->getType(); 595 Expr* expr = IList->getInit(startIndex); 596 if (InitListExpr *SubInitList = dyn_cast<InitListExpr>(expr)) { 597 unsigned newStart = 0; 598 hadError |= CheckInitializerListTypes(SubInitList, fieldType, 599 true, newStart); 600 ++startIndex; 601 } else { 602 hadError |= CheckInitializerListTypes(IList, fieldType, 603 false, startIndex); 604 } 605 if (DeclType->isUnionType()) 606 break; 607 } 608 // FIXME: Implement flexible array initialization GCC extension (it's a 609 // really messy extension to implement, unfortunately...the necessary 610 // information isn't actually even here!) 611 } 612 } else if (DeclType->isArrayType()) { 613 // Check for the special-case of initializing an array with a string. 614 if (startIndex < IList->getNumInits()) { 615 if (StringLiteral *lit = IsStringLiteralInit(IList->getInit(startIndex), 616 DeclType)) { 617 CheckStringLiteralInit(lit, DeclType); 618 ++startIndex; 619 if (topLevel && startIndex < IList->getNumInits()) { 620 // We have leftover initializers; warn 621 Diag(IList->getInit(startIndex)->getLocStart(), 622 diag::err_excess_initializers_in_char_array_initializer, 623 IList->getInit(startIndex)->getSourceRange()); 624 } 625 return false; 626 } 627 } 628 int maxElements; 629 if (DeclType->isIncompleteArrayType()) { 630 // FIXME: use a proper constant 631 maxElements = 0x7FFFFFFF; 632 } else if (const VariableArrayType *VAT = 633 DeclType->getAsVariableArrayType()) { 634 // Check for VLAs; in standard C it would be possible to check this 635 // earlier, but I don't know where clang accepts VLAs (gcc accepts 636 // them in all sorts of strange places). 637 Diag(VAT->getSizeExpr()->getLocStart(), 638 diag::err_variable_object_no_init, 639 VAT->getSizeExpr()->getSourceRange()); 640 hadError = true; 641 maxElements = 0x7FFFFFFF; 642 } else { 643 const ConstantArrayType *CAT = DeclType->getAsConstantArrayType(); 644 maxElements = static_cast<int>(CAT->getSize().getZExtValue()); 645 } 646 QualType elementType = DeclType->getAsArrayType()->getElementType(); 647 int numElements = 0; 648 for (int i = 0; i < maxElements; ++i, ++numElements) { 649 // Don't attempt to go past the end of the init list 650 if (startIndex >= IList->getNumInits()) 651 break; 652 Expr* expr = IList->getInit(startIndex); 653 if (InitListExpr *SubInitList = dyn_cast<InitListExpr>(expr)) { 654 unsigned newIndex = 0; 655 hadError |= CheckInitializerListTypes(SubInitList, elementType, 656 true, newIndex); 657 ++startIndex; 658 } else { 659 hadError |= CheckInitializerListTypes(IList, elementType, 660 false, startIndex); 661 } 662 } 663 if (DeclType->isIncompleteArrayType()) { 664 // If this is an incomplete array type, the actual type needs to 665 // be calculated here 666 if (numElements == 0) { 667 // Sizing an array implicitly to zero is not allowed 668 // (It could in theory be allowed, but it doesn't really matter.) 669 Diag(IList->getLocStart(), 670 diag::err_at_least_one_initializer_needed_to_size_array); 671 hadError = true; 672 } else { 673 llvm::APSInt ConstVal(32); 674 ConstVal = numElements; 675 DeclType = Context.getConstantArrayType(elementType, ConstVal, 676 ArrayType::Normal, 0); 677 } 678 } 679 } else { 680 assert(0 && "Aggregate that isn't a function or array?!"); 681 } 682 } else { 683 // In C, all types are either scalars or aggregates, but 684 // additional handling is needed here for C++ (and possibly others?). 685 assert(0 && "Unsupported initializer type"); 686 } 687 688 // If this init list is a base list, we set the type; an initializer doesn't 689 // fundamentally have a type, but this makes the ASTs a bit easier to read 690 if (topLevel) 691 IList->setType(DeclType); 692 693 if (topLevel && startIndex < IList->getNumInits()) { 694 // We have leftover initializers; warn 695 Diag(IList->getInit(startIndex)->getLocStart(), 696 diag::warn_excess_initializers, 697 IList->getInit(startIndex)->getSourceRange()); 698 } 699 return hadError; 700} 701 702bool Sema::CheckInitializerTypes(Expr *&Init, QualType &DeclType) { 703 // C99 6.7.8p3: The type of the entity to be initialized shall be an array 704 // of unknown size ("[]") or an object type that is not a variable array type. 705 if (const VariableArrayType *VAT = DeclType->getAsVariableArrayType()) 706 return Diag(VAT->getSizeExpr()->getLocStart(), 707 diag::err_variable_object_no_init, 708 VAT->getSizeExpr()->getSourceRange()); 709 710 InitListExpr *InitList = dyn_cast<InitListExpr>(Init); 711 if (!InitList) { 712 // FIXME: Handle wide strings 713 if (StringLiteral *strLiteral = IsStringLiteralInit(Init, DeclType)) 714 return CheckStringLiteralInit(strLiteral, DeclType); 715 716 if (DeclType->isArrayType()) 717 return Diag(Init->getLocStart(), 718 diag::err_array_init_list_required, 719 Init->getSourceRange()); 720 721 return CheckSingleInitializer(Init, DeclType); 722 } 723 unsigned newIndex = 0; 724 return CheckInitializerListTypes(InitList, DeclType, true, newIndex); 725} 726 727Sema::DeclTy * 728Sema::ActOnDeclarator(Scope *S, Declarator &D, DeclTy *lastDecl) { 729 ScopedDecl *LastDeclarator = dyn_cast_or_null<ScopedDecl>((Decl *)lastDecl); 730 IdentifierInfo *II = D.getIdentifier(); 731 732 // All of these full declarators require an identifier. If it doesn't have 733 // one, the ParsedFreeStandingDeclSpec action should be used. 734 if (II == 0) { 735 Diag(D.getDeclSpec().getSourceRange().getBegin(), 736 diag::err_declarator_need_ident, 737 D.getDeclSpec().getSourceRange(), D.getSourceRange()); 738 return 0; 739 } 740 741 // The scope passed in may not be a decl scope. Zip up the scope tree until 742 // we find one that is. 743 while ((S->getFlags() & Scope::DeclScope) == 0) 744 S = S->getParent(); 745 746 // See if this is a redefinition of a variable in the same scope. 747 Decl *PrevDecl = LookupDecl(II, Decl::IDNS_Ordinary, S); 748 ScopedDecl *New; 749 bool InvalidDecl = false; 750 751 // In C++, the previous declaration we find might be a tag type 752 // (class or enum). In this case, the new declaration will hide the 753 // tag type. 754 if (PrevDecl && PrevDecl->getIdentifierNamespace() == Decl::IDNS_Tag) 755 PrevDecl = 0; 756 757 QualType R = GetTypeForDeclarator(D, S); 758 assert(!R.isNull() && "GetTypeForDeclarator() returned null type"); 759 760 if (D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_typedef) { 761 TypedefDecl *NewTD = ParseTypedefDecl(S, D, R, LastDeclarator); 762 if (!NewTD) return 0; 763 764 // Handle attributes prior to checking for duplicates in MergeVarDecl 765 HandleDeclAttributes(NewTD, D.getDeclSpec().getAttributes(), 766 D.getAttributes()); 767 // Merge the decl with the existing one if appropriate. If the decl is 768 // in an outer scope, it isn't the same thing. 769 if (PrevDecl && S->isDeclScope(PrevDecl)) { 770 NewTD = MergeTypeDefDecl(NewTD, PrevDecl); 771 if (NewTD == 0) return 0; 772 } 773 New = NewTD; 774 if (S->getParent() == 0) { 775 // C99 6.7.7p2: If a typedef name specifies a variably modified type 776 // then it shall have block scope. 777 if (NewTD->getUnderlyingType()->isVariablyModifiedType()) { 778 // FIXME: Diagnostic needs to be fixed. 779 Diag(D.getIdentifierLoc(), diag::err_typecheck_illegal_vla); 780 InvalidDecl = true; 781 } 782 } 783 } else if (R.getTypePtr()->isFunctionType()) { 784 FunctionDecl::StorageClass SC = FunctionDecl::None; 785 switch (D.getDeclSpec().getStorageClassSpec()) { 786 default: assert(0 && "Unknown storage class!"); 787 case DeclSpec::SCS_auto: 788 case DeclSpec::SCS_register: 789 Diag(D.getIdentifierLoc(), diag::err_typecheck_sclass_func, 790 R.getAsString()); 791 InvalidDecl = true; 792 break; 793 case DeclSpec::SCS_unspecified: SC = FunctionDecl::None; break; 794 case DeclSpec::SCS_extern: SC = FunctionDecl::Extern; break; 795 case DeclSpec::SCS_static: SC = FunctionDecl::Static; break; 796 case DeclSpec::SCS_private_extern: SC = FunctionDecl::PrivateExtern;break; 797 } 798 799 bool isInline = D.getDeclSpec().isInlineSpecified(); 800 FunctionDecl *NewFD = FunctionDecl::Create(Context, CurContext, 801 D.getIdentifierLoc(), 802 II, R, SC, isInline, 803 LastDeclarator); 804 // Handle attributes. 805 HandleDeclAttributes(NewFD, D.getDeclSpec().getAttributes(), 806 D.getAttributes()); 807 808 // Copy the parameter declarations from the declarator D to 809 // the function declaration NewFD, if they are available. 810 if (D.getNumTypeObjects() > 0 && 811 D.getTypeObject(0).Fun.hasPrototype) { 812 DeclaratorChunk::FunctionTypeInfo &FTI = D.getTypeObject(0).Fun; 813 814 // Create Decl objects for each parameter, adding them to the 815 // FunctionDecl. 816 llvm::SmallVector<ParmVarDecl*, 16> Params; 817 818 // Check for C99 6.7.5.3p10 - foo(void) is a non-varargs 819 // function that takes no arguments, not a function that takes a 820 // single void argument. 821 if (FTI.NumArgs == 1 && !FTI.isVariadic && FTI.ArgInfo[0].Ident == 0 && 822 FTI.ArgInfo[0].Param && 823 !((ParmVarDecl*)FTI.ArgInfo[0].Param)->getType().getCVRQualifiers() && 824 ((ParmVarDecl*)FTI.ArgInfo[0].Param)->getType()->isVoidType()) { 825 // empty arg list, don't push any params. 826 ParmVarDecl *Param = (ParmVarDecl*)FTI.ArgInfo[0].Param; 827 828 // In C++, the empty parameter-type-list must be spelled "void"; a 829 // typedef of void is not permitted. 830 if (getLangOptions().CPlusPlus && 831 Param->getType() != Context.VoidTy) { 832 Diag(Param->getLocation(), diag::ext_param_typedef_of_void); 833 } 834 835 } else { 836 for (unsigned i = 0, e = FTI.NumArgs; i != e; ++i) 837 Params.push_back((ParmVarDecl *)FTI.ArgInfo[i].Param); 838 } 839 840 NewFD->setParams(&Params[0], Params.size()); 841 } 842 843 // Merge the decl with the existing one if appropriate. Since C functions 844 // are in a flat namespace, make sure we consider decls in outer scopes. 845 if (PrevDecl) { 846 NewFD = MergeFunctionDecl(NewFD, PrevDecl); 847 if (NewFD == 0) return 0; 848 } 849 New = NewFD; 850 851 // In C++, check default arguments now that we have merged decls. 852 if (getLangOptions().CPlusPlus) 853 CheckCXXDefaultArguments(NewFD); 854 } else { 855 if (R.getTypePtr()->isObjCInterfaceType()) { 856 Diag(D.getIdentifierLoc(), diag::err_statically_allocated_object, 857 D.getIdentifier()->getName()); 858 InvalidDecl = true; 859 } 860 861 VarDecl *NewVD; 862 VarDecl::StorageClass SC; 863 switch (D.getDeclSpec().getStorageClassSpec()) { 864 default: assert(0 && "Unknown storage class!"); 865 case DeclSpec::SCS_unspecified: SC = VarDecl::None; break; 866 case DeclSpec::SCS_extern: SC = VarDecl::Extern; break; 867 case DeclSpec::SCS_static: SC = VarDecl::Static; break; 868 case DeclSpec::SCS_auto: SC = VarDecl::Auto; break; 869 case DeclSpec::SCS_register: SC = VarDecl::Register; break; 870 case DeclSpec::SCS_private_extern: SC = VarDecl::PrivateExtern; break; 871 } 872 if (S->getParent() == 0) { 873 // C99 6.9p2: The storage-class specifiers auto and register shall not 874 // appear in the declaration specifiers in an external declaration. 875 if (SC == VarDecl::Auto || SC == VarDecl::Register) { 876 Diag(D.getIdentifierLoc(), diag::err_typecheck_sclass_fscope, 877 R.getAsString()); 878 InvalidDecl = true; 879 } 880 NewVD = VarDecl::Create(Context, CurContext, D.getIdentifierLoc(), 881 II, R, SC, LastDeclarator); 882 } else { 883 NewVD = VarDecl::Create(Context, CurContext, D.getIdentifierLoc(), 884 II, R, SC, LastDeclarator); 885 } 886 // Handle attributes prior to checking for duplicates in MergeVarDecl 887 HandleDeclAttributes(NewVD, D.getDeclSpec().getAttributes(), 888 D.getAttributes()); 889 890 // Emit an error if an address space was applied to decl with local storage. 891 // This includes arrays of objects with address space qualifiers, but not 892 // automatic variables that point to other address spaces. 893 // ISO/IEC TR 18037 S5.1.2 894 if (NewVD->hasLocalStorage() && (NewVD->getType().getAddressSpace() != 0)) { 895 Diag(D.getIdentifierLoc(), diag::err_as_qualified_auto_decl); 896 InvalidDecl = true; 897 } 898 // Merge the decl with the existing one if appropriate. If the decl is 899 // in an outer scope, it isn't the same thing. 900 if (PrevDecl && S->isDeclScope(PrevDecl)) { 901 NewVD = MergeVarDecl(NewVD, PrevDecl); 902 if (NewVD == 0) return 0; 903 } 904 New = NewVD; 905 } 906 907 // If this has an identifier, add it to the scope stack. 908 if (II) 909 PushOnScopeChains(New, S); 910 // If any semantic error occurred, mark the decl as invalid. 911 if (D.getInvalidType() || InvalidDecl) 912 New->setInvalidDecl(); 913 914 return New; 915} 916 917bool Sema::CheckForConstantInitializer(Expr *Init, QualType DclT) { 918 SourceLocation loc; 919 // FIXME: Remove the isReference check and handle assignment to a reference. 920 if (!DclT->isReferenceType() && !Init->isConstantExpr(Context, &loc)) { 921 assert(loc.isValid() && "isConstantExpr didn't return a loc!"); 922 Diag(loc, diag::err_init_element_not_constant, Init->getSourceRange()); 923 return true; 924 } 925 return false; 926} 927 928void Sema::AddInitializerToDecl(DeclTy *dcl, ExprTy *init) { 929 Decl *RealDecl = static_cast<Decl *>(dcl); 930 Expr *Init = static_cast<Expr *>(init); 931 assert(Init && "missing initializer"); 932 933 // If there is no declaration, there was an error parsing it. Just ignore 934 // the initializer. 935 if (RealDecl == 0) { 936 delete Init; 937 return; 938 } 939 940 VarDecl *VDecl = dyn_cast<VarDecl>(RealDecl); 941 if (!VDecl) { 942 Diag(dyn_cast<ScopedDecl>(RealDecl)->getLocation(), 943 diag::err_illegal_initializer); 944 RealDecl->setInvalidDecl(); 945 return; 946 } 947 // Get the decls type and save a reference for later, since 948 // CheckInitializerTypes may change it. 949 QualType DclT = VDecl->getType(), SavT = DclT; 950 if (VDecl->isBlockVarDecl()) { 951 VarDecl::StorageClass SC = VDecl->getStorageClass(); 952 if (SC == VarDecl::Extern) { // C99 6.7.8p5 953 Diag(VDecl->getLocation(), diag::err_block_extern_cant_init); 954 VDecl->setInvalidDecl(); 955 } else if (!VDecl->isInvalidDecl()) { 956 if (CheckInitializerTypes(Init, DclT)) 957 VDecl->setInvalidDecl(); 958 if (SC == VarDecl::Static) // C99 6.7.8p4. 959 CheckForConstantInitializer(Init, DclT); 960 } 961 } else if (VDecl->isFileVarDecl()) { 962 if (VDecl->getStorageClass() == VarDecl::Extern) 963 Diag(VDecl->getLocation(), diag::warn_extern_init); 964 if (!VDecl->isInvalidDecl()) 965 if (CheckInitializerTypes(Init, DclT)) 966 VDecl->setInvalidDecl(); 967 968 // C99 6.7.8p4. All file scoped initializers need to be constant. 969 CheckForConstantInitializer(Init, DclT); 970 } 971 // If the type changed, it means we had an incomplete type that was 972 // completed by the initializer. For example: 973 // int ary[] = { 1, 3, 5 }; 974 // "ary" transitions from a VariableArrayType to a ConstantArrayType. 975 if (!VDecl->isInvalidDecl() && (DclT != SavT)) { 976 VDecl->setType(DclT); 977 Init->setType(DclT); 978 } 979 980 // Attach the initializer to the decl. 981 VDecl->setInit(Init); 982 return; 983} 984 985/// The declarators are chained together backwards, reverse the list. 986Sema::DeclTy *Sema::FinalizeDeclaratorGroup(Scope *S, DeclTy *group) { 987 // Often we have single declarators, handle them quickly. 988 Decl *GroupDecl = static_cast<Decl*>(group); 989 if (GroupDecl == 0) 990 return 0; 991 992 ScopedDecl *Group = dyn_cast<ScopedDecl>(GroupDecl); 993 ScopedDecl *NewGroup = 0; 994 if (Group->getNextDeclarator() == 0) 995 NewGroup = Group; 996 else { // reverse the list. 997 while (Group) { 998 ScopedDecl *Next = Group->getNextDeclarator(); 999 Group->setNextDeclarator(NewGroup); 1000 NewGroup = Group; 1001 Group = Next; 1002 } 1003 } 1004 // Perform semantic analysis that depends on having fully processed both 1005 // the declarator and initializer. 1006 for (ScopedDecl *ID = NewGroup; ID; ID = ID->getNextDeclarator()) { 1007 VarDecl *IDecl = dyn_cast<VarDecl>(ID); 1008 if (!IDecl) 1009 continue; 1010 QualType T = IDecl->getType(); 1011 1012 // C99 6.7.5.2p2: If an identifier is declared to be an object with 1013 // static storage duration, it shall not have a variable length array. 1014 if ((IDecl->isFileVarDecl() || IDecl->isBlockVarDecl()) && 1015 IDecl->getStorageClass() == VarDecl::Static) { 1016 if (T->getAsVariableArrayType()) { 1017 Diag(IDecl->getLocation(), diag::err_typecheck_illegal_vla); 1018 IDecl->setInvalidDecl(); 1019 } 1020 } 1021 // Block scope. C99 6.7p7: If an identifier for an object is declared with 1022 // no linkage (C99 6.2.2p6), the type for the object shall be complete... 1023 if (IDecl->isBlockVarDecl() && 1024 IDecl->getStorageClass() != VarDecl::Extern) { 1025 if (T->isIncompleteType() && !IDecl->isInvalidDecl()) { 1026 Diag(IDecl->getLocation(), diag::err_typecheck_decl_incomplete_type, 1027 T.getAsString()); 1028 IDecl->setInvalidDecl(); 1029 } 1030 } 1031 // File scope. C99 6.9.2p2: A declaration of an identifier for and 1032 // object that has file scope without an initializer, and without a 1033 // storage-class specifier or with the storage-class specifier "static", 1034 // constitutes a tentative definition. Note: A tentative definition with 1035 // external linkage is valid (C99 6.2.2p5). 1036 if (IDecl && !IDecl->getInit() && 1037 (IDecl->getStorageClass() == VarDecl::Static || 1038 IDecl->getStorageClass() == VarDecl::None)) { 1039 if (T->isIncompleteArrayType()) { 1040 // C99 6.9.2 (p2, p5): Implicit initialization causes an incomplete 1041 // array to be completed. Don't issue a diagnostic. 1042 } else if (T->isIncompleteType() && !IDecl->isInvalidDecl()) { 1043 // C99 6.9.2p3: If the declaration of an identifier for an object is 1044 // a tentative definition and has internal linkage (C99 6.2.2p3), the 1045 // declared type shall not be an incomplete type. 1046 Diag(IDecl->getLocation(), diag::err_typecheck_decl_incomplete_type, 1047 T.getAsString()); 1048 IDecl->setInvalidDecl(); 1049 } 1050 } 1051 } 1052 return NewGroup; 1053} 1054 1055/// ActOnParamDeclarator - Called from Parser::ParseFunctionDeclarator() 1056/// to introduce parameters into function prototype scope. 1057Sema::DeclTy * 1058Sema::ActOnParamDeclarator(Scope *S, Declarator &D) { 1059 DeclSpec &DS = D.getDeclSpec(); 1060 1061 // Verify C99 6.7.5.3p2: The only SCS allowed is 'register'. 1062 if (DS.getStorageClassSpec() != DeclSpec::SCS_unspecified && 1063 DS.getStorageClassSpec() != DeclSpec::SCS_register) { 1064 Diag(DS.getStorageClassSpecLoc(), 1065 diag::err_invalid_storage_class_in_func_decl); 1066 DS.ClearStorageClassSpecs(); 1067 } 1068 if (DS.isThreadSpecified()) { 1069 Diag(DS.getThreadSpecLoc(), 1070 diag::err_invalid_storage_class_in_func_decl); 1071 DS.ClearStorageClassSpecs(); 1072 } 1073 1074 1075 // In this context, we *do not* check D.getInvalidType(). If the declarator 1076 // type was invalid, GetTypeForDeclarator() still returns a "valid" type, 1077 // though it will not reflect the user specified type. 1078 QualType parmDeclType = GetTypeForDeclarator(D, S); 1079 1080 assert(!parmDeclType.isNull() && "GetTypeForDeclarator() returned null type"); 1081 1082 // TODO: CHECK FOR CONFLICTS, multiple decls with same name in one scope. 1083 // Can this happen for params? We already checked that they don't conflict 1084 // among each other. Here they can only shadow globals, which is ok. 1085 IdentifierInfo *II = D.getIdentifier(); 1086 if (Decl *PrevDecl = LookupDecl(II, Decl::IDNS_Ordinary, S)) { 1087 if (S->isDeclScope(PrevDecl)) { 1088 Diag(D.getIdentifierLoc(), diag::err_param_redefinition, 1089 dyn_cast<NamedDecl>(PrevDecl)->getName()); 1090 1091 // Recover by removing the name 1092 II = 0; 1093 D.SetIdentifier(0, D.getIdentifierLoc()); 1094 } 1095 } 1096 1097 // Perform the default function/array conversion (C99 6.7.5.3p[7,8]). 1098 // Doing the promotion here has a win and a loss. The win is the type for 1099 // both Decl's and DeclRefExpr's will match (a convenient invariant for the 1100 // code generator). The loss is the orginal type isn't preserved. For example: 1101 // 1102 // void func(int parmvardecl[5]) { // convert "int [5]" to "int *" 1103 // int blockvardecl[5]; 1104 // sizeof(parmvardecl); // size == 4 1105 // sizeof(blockvardecl); // size == 20 1106 // } 1107 // 1108 // For expressions, all implicit conversions are captured using the 1109 // ImplicitCastExpr AST node (we have no such mechanism for Decl's). 1110 // 1111 // FIXME: If a source translation tool needs to see the original type, then 1112 // we need to consider storing both types (in ParmVarDecl)... 1113 // 1114 if (parmDeclType->isArrayType()) { 1115 // int x[restrict 4] -> int *restrict 1116 parmDeclType = Context.getArrayDecayedType(parmDeclType); 1117 } else if (parmDeclType->isFunctionType()) 1118 parmDeclType = Context.getPointerType(parmDeclType); 1119 1120 ParmVarDecl *New = ParmVarDecl::Create(Context, CurContext, 1121 D.getIdentifierLoc(), II, 1122 parmDeclType, VarDecl::None, 1123 0, 0); 1124 1125 if (D.getInvalidType()) 1126 New->setInvalidDecl(); 1127 1128 if (II) 1129 PushOnScopeChains(New, S); 1130 1131 HandleDeclAttributes(New, D.getAttributes(), 0); 1132 return New; 1133 1134} 1135 1136Sema::DeclTy *Sema::ActOnStartOfFunctionDef(Scope *FnBodyScope, Declarator &D) { 1137 assert(CurFunctionDecl == 0 && "Function parsing confused"); 1138 assert(D.getTypeObject(0).Kind == DeclaratorChunk::Function && 1139 "Not a function declarator!"); 1140 DeclaratorChunk::FunctionTypeInfo &FTI = D.getTypeObject(0).Fun; 1141 1142 // Verify 6.9.1p6: 'every identifier in the identifier list shall be declared' 1143 // for a K&R function. 1144 if (!FTI.hasPrototype) { 1145 for (unsigned i = 0, e = FTI.NumArgs; i != e; ++i) { 1146 if (FTI.ArgInfo[i].Param == 0) { 1147 Diag(FTI.ArgInfo[i].IdentLoc, diag::ext_param_not_declared, 1148 FTI.ArgInfo[i].Ident->getName()); 1149 // Implicitly declare the argument as type 'int' for lack of a better 1150 // type. 1151 DeclSpec DS; 1152 const char* PrevSpec; // unused 1153 DS.SetTypeSpecType(DeclSpec::TST_int, FTI.ArgInfo[i].IdentLoc, 1154 PrevSpec); 1155 Declarator ParamD(DS, Declarator::KNRTypeListContext); 1156 ParamD.SetIdentifier(FTI.ArgInfo[i].Ident, FTI.ArgInfo[i].IdentLoc); 1157 FTI.ArgInfo[i].Param = ActOnParamDeclarator(FnBodyScope, ParamD); 1158 } 1159 } 1160 1161 // Since this is a function definition, act as though we have information 1162 // about the arguments. 1163 if (FTI.NumArgs) 1164 FTI.hasPrototype = true; 1165 } else { 1166 // FIXME: Diagnose arguments without names in C. 1167 } 1168 1169 Scope *GlobalScope = FnBodyScope->getParent(); 1170 1171 // See if this is a redefinition. 1172 Decl *PrevDcl = LookupDecl(D.getIdentifier(), Decl::IDNS_Ordinary, 1173 GlobalScope); 1174 if (FunctionDecl *FD = dyn_cast_or_null<FunctionDecl>(PrevDcl)) { 1175 if (FD->getBody()) { 1176 Diag(D.getIdentifierLoc(), diag::err_redefinition, 1177 D.getIdentifier()->getName()); 1178 Diag(FD->getLocation(), diag::err_previous_definition); 1179 } 1180 } 1181 Decl *decl = static_cast<Decl*>(ActOnDeclarator(GlobalScope, D, 0)); 1182 FunctionDecl *FD = cast<FunctionDecl>(decl); 1183 CurFunctionDecl = FD; 1184 PushDeclContext(FD); 1185 1186 // Check the validity of our function parameters 1187 CheckParmsForFunctionDef(FD); 1188 1189 // Introduce our parameters into the function scope 1190 for (unsigned p = 0, NumParams = FD->getNumParams(); p < NumParams; ++p) { 1191 ParmVarDecl *Param = FD->getParamDecl(p); 1192 // If this has an identifier, add it to the scope stack. 1193 if (Param->getIdentifier()) 1194 PushOnScopeChains(Param, FnBodyScope); 1195 } 1196 1197 return FD; 1198} 1199 1200Sema::DeclTy *Sema::ActOnFinishFunctionBody(DeclTy *D, StmtTy *Body) { 1201 Decl *dcl = static_cast<Decl *>(D); 1202 if (FunctionDecl *FD = dyn_cast<FunctionDecl>(dcl)) { 1203 FD->setBody((Stmt*)Body); 1204 assert(FD == CurFunctionDecl && "Function parsing confused"); 1205 CurFunctionDecl = 0; 1206 } else if (ObjCMethodDecl *MD = dyn_cast<ObjCMethodDecl>(dcl)) { 1207 MD->setBody((Stmt*)Body); 1208 CurMethodDecl = 0; 1209 } 1210 PopDeclContext(); 1211 // Verify and clean out per-function state. 1212 1213 // Check goto/label use. 1214 for (llvm::DenseMap<IdentifierInfo*, LabelStmt*>::iterator 1215 I = LabelMap.begin(), E = LabelMap.end(); I != E; ++I) { 1216 // Verify that we have no forward references left. If so, there was a goto 1217 // or address of a label taken, but no definition of it. Label fwd 1218 // definitions are indicated with a null substmt. 1219 if (I->second->getSubStmt() == 0) { 1220 LabelStmt *L = I->second; 1221 // Emit error. 1222 Diag(L->getIdentLoc(), diag::err_undeclared_label_use, L->getName()); 1223 1224 // At this point, we have gotos that use the bogus label. Stitch it into 1225 // the function body so that they aren't leaked and that the AST is well 1226 // formed. 1227 if (Body) { 1228 L->setSubStmt(new NullStmt(L->getIdentLoc())); 1229 cast<CompoundStmt>((Stmt*)Body)->push_back(L); 1230 } else { 1231 // The whole function wasn't parsed correctly, just delete this. 1232 delete L; 1233 } 1234 } 1235 } 1236 LabelMap.clear(); 1237 1238 return D; 1239} 1240 1241/// ImplicitlyDefineFunction - An undeclared identifier was used in a function 1242/// call, forming a call to an implicitly defined function (per C99 6.5.1p2). 1243ScopedDecl *Sema::ImplicitlyDefineFunction(SourceLocation Loc, 1244 IdentifierInfo &II, Scope *S) { 1245 if (getLangOptions().C99) // Extension in C99. 1246 Diag(Loc, diag::ext_implicit_function_decl, II.getName()); 1247 else // Legal in C90, but warn about it. 1248 Diag(Loc, diag::warn_implicit_function_decl, II.getName()); 1249 1250 // FIXME: handle stuff like: 1251 // void foo() { extern float X(); } 1252 // void bar() { X(); } <-- implicit decl for X in another scope. 1253 1254 // Set a Declarator for the implicit definition: int foo(); 1255 const char *Dummy; 1256 DeclSpec DS; 1257 bool Error = DS.SetTypeSpecType(DeclSpec::TST_int, Loc, Dummy); 1258 Error = Error; // Silence warning. 1259 assert(!Error && "Error setting up implicit decl!"); 1260 Declarator D(DS, Declarator::BlockContext); 1261 D.AddTypeInfo(DeclaratorChunk::getFunction(false, false, 0, 0, Loc)); 1262 D.SetIdentifier(&II, Loc); 1263 1264 // Find translation-unit scope to insert this function into. 1265 if (Scope *FnS = S->getFnParent()) 1266 S = FnS->getParent(); // Skip all scopes in a function at once. 1267 while (S->getParent()) 1268 S = S->getParent(); 1269 1270 FunctionDecl *FD = 1271 dyn_cast<FunctionDecl>(static_cast<Decl*>(ActOnDeclarator(S, D, 0))); 1272 FD->setImplicit(); 1273 return FD; 1274} 1275 1276 1277TypedefDecl *Sema::ParseTypedefDecl(Scope *S, Declarator &D, QualType T, 1278 ScopedDecl *LastDeclarator) { 1279 assert(D.getIdentifier() && "Wrong callback for declspec without declarator"); 1280 assert(!T.isNull() && "GetTypeForDeclarator() returned null type"); 1281 1282 // Scope manipulation handled by caller. 1283 TypedefDecl *NewTD = TypedefDecl::Create(Context, CurContext, 1284 D.getIdentifierLoc(), 1285 D.getIdentifier(), 1286 T, LastDeclarator); 1287 if (D.getInvalidType()) 1288 NewTD->setInvalidDecl(); 1289 return NewTD; 1290} 1291 1292/// ActOnTag - This is invoked when we see 'struct foo' or 'struct {'. In the 1293/// former case, Name will be non-null. In the later case, Name will be null. 1294/// TagType indicates what kind of tag this is. TK indicates whether this is a 1295/// reference/declaration/definition of a tag. 1296Sema::DeclTy *Sema::ActOnTag(Scope *S, unsigned TagType, TagKind TK, 1297 SourceLocation KWLoc, IdentifierInfo *Name, 1298 SourceLocation NameLoc, AttributeList *Attr) { 1299 // If this is a use of an existing tag, it must have a name. 1300 assert((Name != 0 || TK == TK_Definition) && 1301 "Nameless record must be a definition!"); 1302 1303 Decl::Kind Kind; 1304 switch (TagType) { 1305 default: assert(0 && "Unknown tag type!"); 1306 case DeclSpec::TST_struct: Kind = Decl::Struct; break; 1307 case DeclSpec::TST_union: Kind = Decl::Union; break; 1308 case DeclSpec::TST_class: Kind = Decl::Class; break; 1309 case DeclSpec::TST_enum: Kind = Decl::Enum; break; 1310 } 1311 1312 // If this is a named struct, check to see if there was a previous forward 1313 // declaration or definition. 1314 if (TagDecl *PrevDecl = 1315 dyn_cast_or_null<TagDecl>(LookupDecl(Name, Decl::IDNS_Tag, S))) { 1316 1317 // If this is a use of a previous tag, or if the tag is already declared in 1318 // the same scope (so that the definition/declaration completes or 1319 // rementions the tag), reuse the decl. 1320 if (TK == TK_Reference || S->isDeclScope(PrevDecl)) { 1321 // Make sure that this wasn't declared as an enum and now used as a struct 1322 // or something similar. 1323 if (PrevDecl->getKind() != Kind) { 1324 Diag(KWLoc, diag::err_use_with_wrong_tag, Name->getName()); 1325 Diag(PrevDecl->getLocation(), diag::err_previous_use); 1326 } 1327 1328 // If this is a use or a forward declaration, we're good. 1329 if (TK != TK_Definition) 1330 return PrevDecl; 1331 1332 // Diagnose attempts to redefine a tag. 1333 if (PrevDecl->isDefinition()) { 1334 Diag(NameLoc, diag::err_redefinition, Name->getName()); 1335 Diag(PrevDecl->getLocation(), diag::err_previous_definition); 1336 // If this is a redefinition, recover by making this struct be 1337 // anonymous, which will make any later references get the previous 1338 // definition. 1339 Name = 0; 1340 } else { 1341 // Okay, this is definition of a previously declared or referenced tag. 1342 // Move the location of the decl to be the definition site. 1343 PrevDecl->setLocation(NameLoc); 1344 return PrevDecl; 1345 } 1346 } 1347 // If we get here, this is a definition of a new struct type in a nested 1348 // scope, e.g. "struct foo; void bar() { struct foo; }", just create a new 1349 // type. 1350 } 1351 1352 // If there is an identifier, use the location of the identifier as the 1353 // location of the decl, otherwise use the location of the struct/union 1354 // keyword. 1355 SourceLocation Loc = NameLoc.isValid() ? NameLoc : KWLoc; 1356 1357 // Otherwise, if this is the first time we've seen this tag, create the decl. 1358 TagDecl *New; 1359 switch (Kind) { 1360 default: assert(0 && "Unknown tag kind!"); 1361 case Decl::Enum: 1362 // FIXME: Tag decls should be chained to any simultaneous vardecls, e.g.: 1363 // enum X { A, B, C } D; D should chain to X. 1364 New = EnumDecl::Create(Context, CurContext, Loc, Name, 0); 1365 // If this is an undefined enum, warn. 1366 if (TK != TK_Definition) Diag(Loc, diag::ext_forward_ref_enum); 1367 break; 1368 case Decl::Union: 1369 case Decl::Struct: 1370 case Decl::Class: 1371 // FIXME: Tag decls should be chained to any simultaneous vardecls, e.g.: 1372 // struct X { int A; } D; D should chain to X. 1373 New = RecordDecl::Create(Context, Kind, CurContext, Loc, Name, 0); 1374 break; 1375 } 1376 1377 // If this has an identifier, add it to the scope stack. 1378 if (Name) { 1379 // The scope passed in may not be a decl scope. Zip up the scope tree until 1380 // we find one that is. 1381 while ((S->getFlags() & Scope::DeclScope) == 0) 1382 S = S->getParent(); 1383 1384 // Add it to the decl chain. 1385 PushOnScopeChains(New, S); 1386 } 1387 1388 HandleDeclAttributes(New, Attr, 0); 1389 return New; 1390} 1391 1392/// ActOnField - Each field of a struct/union/class is passed into this in order 1393/// to create a FieldDecl object for it. 1394Sema::DeclTy *Sema::ActOnField(Scope *S, 1395 SourceLocation DeclStart, 1396 Declarator &D, ExprTy *BitfieldWidth) { 1397 IdentifierInfo *II = D.getIdentifier(); 1398 Expr *BitWidth = (Expr*)BitfieldWidth; 1399 SourceLocation Loc = DeclStart; 1400 if (II) Loc = D.getIdentifierLoc(); 1401 1402 // FIXME: Unnamed fields can be handled in various different ways, for 1403 // example, unnamed unions inject all members into the struct namespace! 1404 1405 1406 if (BitWidth) { 1407 // TODO: Validate. 1408 //printf("WARNING: BITFIELDS IGNORED!\n"); 1409 1410 // 6.7.2.1p3 1411 // 6.7.2.1p4 1412 1413 } else { 1414 // Not a bitfield. 1415 1416 // validate II. 1417 1418 } 1419 1420 QualType T = GetTypeForDeclarator(D, S); 1421 assert(!T.isNull() && "GetTypeForDeclarator() returned null type"); 1422 bool InvalidDecl = false; 1423 1424 // C99 6.7.2.1p8: A member of a structure or union may have any type other 1425 // than a variably modified type. 1426 if (T->isVariablyModifiedType()) { 1427 // FIXME: This diagnostic needs work 1428 Diag(Loc, diag::err_typecheck_illegal_vla, Loc); 1429 InvalidDecl = true; 1430 } 1431 // FIXME: Chain fielddecls together. 1432 FieldDecl *NewFD = FieldDecl::Create(Context, Loc, II, T, BitWidth); 1433 1434 HandleDeclAttributes(NewFD, D.getDeclSpec().getAttributes(), 1435 D.getAttributes()); 1436 1437 if (D.getInvalidType() || InvalidDecl) 1438 NewFD->setInvalidDecl(); 1439 return NewFD; 1440} 1441 1442/// TranslateIvarVisibility - Translate visibility from a token ID to an 1443/// AST enum value. 1444static ObjCIvarDecl::AccessControl 1445TranslateIvarVisibility(tok::ObjCKeywordKind ivarVisibility) { 1446 switch (ivarVisibility) { 1447 case tok::objc_private: return ObjCIvarDecl::Private; 1448 case tok::objc_public: return ObjCIvarDecl::Public; 1449 case tok::objc_protected: return ObjCIvarDecl::Protected; 1450 case tok::objc_package: return ObjCIvarDecl::Package; 1451 default: assert(false && "Unknown visitibility kind"); 1452 } 1453} 1454 1455/// ActOnIvar - Each ivar field of an objective-c class is passed into this 1456/// in order to create an IvarDecl object for it. 1457Sema::DeclTy *Sema::ActOnIvar(Scope *S, 1458 SourceLocation DeclStart, 1459 Declarator &D, ExprTy *BitfieldWidth, 1460 tok::ObjCKeywordKind Visibility) { 1461 IdentifierInfo *II = D.getIdentifier(); 1462 Expr *BitWidth = (Expr*)BitfieldWidth; 1463 SourceLocation Loc = DeclStart; 1464 if (II) Loc = D.getIdentifierLoc(); 1465 1466 // FIXME: Unnamed fields can be handled in various different ways, for 1467 // example, unnamed unions inject all members into the struct namespace! 1468 1469 1470 if (BitWidth) { 1471 // TODO: Validate. 1472 //printf("WARNING: BITFIELDS IGNORED!\n"); 1473 1474 // 6.7.2.1p3 1475 // 6.7.2.1p4 1476 1477 } else { 1478 // Not a bitfield. 1479 1480 // validate II. 1481 1482 } 1483 1484 QualType T = GetTypeForDeclarator(D, S); 1485 assert(!T.isNull() && "GetTypeForDeclarator() returned null type"); 1486 bool InvalidDecl = false; 1487 1488 // C99 6.7.2.1p8: A member of a structure or union may have any type other 1489 // than a variably modified type. 1490 if (T->isVariablyModifiedType()) { 1491 // FIXME: This diagnostic needs work 1492 Diag(Loc, diag::err_typecheck_illegal_vla, Loc); 1493 InvalidDecl = true; 1494 } 1495 1496 ObjCIvarDecl *NewID = ObjCIvarDecl::Create(Context, Loc, II, T); 1497 1498 HandleDeclAttributes(NewID, D.getDeclSpec().getAttributes(), 1499 D.getAttributes()); 1500 1501 if (D.getInvalidType() || InvalidDecl) 1502 NewID->setInvalidDecl(); 1503 // If we have visibility info, make sure the AST is set accordingly. 1504 if (Visibility != tok::objc_not_keyword) 1505 NewID->setAccessControl(TranslateIvarVisibility(Visibility)); 1506 return NewID; 1507} 1508 1509void Sema::ActOnFields(Scope* S, 1510 SourceLocation RecLoc, DeclTy *RecDecl, 1511 DeclTy **Fields, unsigned NumFields, 1512 SourceLocation LBrac, SourceLocation RBrac) { 1513 Decl *EnclosingDecl = static_cast<Decl*>(RecDecl); 1514 assert(EnclosingDecl && "missing record or interface decl"); 1515 RecordDecl *Record = dyn_cast<RecordDecl>(EnclosingDecl); 1516 1517 if (Record && Record->isDefinition()) { 1518 // Diagnose code like: 1519 // struct S { struct S {} X; }; 1520 // We discover this when we complete the outer S. Reject and ignore the 1521 // outer S. 1522 Diag(Record->getLocation(), diag::err_nested_redefinition, 1523 Record->getKindName()); 1524 Diag(RecLoc, diag::err_previous_definition); 1525 Record->setInvalidDecl(); 1526 return; 1527 } 1528 // Verify that all the fields are okay. 1529 unsigned NumNamedMembers = 0; 1530 llvm::SmallVector<FieldDecl*, 32> RecFields; 1531 llvm::SmallSet<const IdentifierInfo*, 32> FieldIDs; 1532 1533 for (unsigned i = 0; i != NumFields; ++i) { 1534 1535 FieldDecl *FD = cast_or_null<FieldDecl>(static_cast<Decl*>(Fields[i])); 1536 assert(FD && "missing field decl"); 1537 1538 // Remember all fields. 1539 RecFields.push_back(FD); 1540 1541 // Get the type for the field. 1542 Type *FDTy = FD->getType().getTypePtr(); 1543 1544 // C99 6.7.2.1p2 - A field may not be a function type. 1545 if (FDTy->isFunctionType()) { 1546 Diag(FD->getLocation(), diag::err_field_declared_as_function, 1547 FD->getName()); 1548 FD->setInvalidDecl(); 1549 EnclosingDecl->setInvalidDecl(); 1550 continue; 1551 } 1552 // C99 6.7.2.1p2 - A field may not be an incomplete type except... 1553 if (FDTy->isIncompleteType()) { 1554 if (!Record) { // Incomplete ivar type is always an error. 1555 Diag(FD->getLocation(), diag::err_field_incomplete, FD->getName()); 1556 FD->setInvalidDecl(); 1557 EnclosingDecl->setInvalidDecl(); 1558 continue; 1559 } 1560 if (i != NumFields-1 || // ... that the last member ... 1561 Record->getKind() != Decl::Struct || // ... of a structure ... 1562 !FDTy->isArrayType()) { //... may have incomplete array type. 1563 Diag(FD->getLocation(), diag::err_field_incomplete, FD->getName()); 1564 FD->setInvalidDecl(); 1565 EnclosingDecl->setInvalidDecl(); 1566 continue; 1567 } 1568 if (NumNamedMembers < 1) { //... must have more than named member ... 1569 Diag(FD->getLocation(), diag::err_flexible_array_empty_struct, 1570 FD->getName()); 1571 FD->setInvalidDecl(); 1572 EnclosingDecl->setInvalidDecl(); 1573 continue; 1574 } 1575 // Okay, we have a legal flexible array member at the end of the struct. 1576 if (Record) 1577 Record->setHasFlexibleArrayMember(true); 1578 } 1579 /// C99 6.7.2.1p2 - a struct ending in a flexible array member cannot be the 1580 /// field of another structure or the element of an array. 1581 if (const RecordType *FDTTy = FDTy->getAsRecordType()) { 1582 if (FDTTy->getDecl()->hasFlexibleArrayMember()) { 1583 // If this is a member of a union, then entire union becomes "flexible". 1584 if (Record && Record->getKind() == Decl::Union) { 1585 Record->setHasFlexibleArrayMember(true); 1586 } else { 1587 // If this is a struct/class and this is not the last element, reject 1588 // it. Note that GCC supports variable sized arrays in the middle of 1589 // structures. 1590 if (i != NumFields-1) { 1591 Diag(FD->getLocation(), diag::err_variable_sized_type_in_struct, 1592 FD->getName()); 1593 FD->setInvalidDecl(); 1594 EnclosingDecl->setInvalidDecl(); 1595 continue; 1596 } 1597 // We support flexible arrays at the end of structs in other structs 1598 // as an extension. 1599 Diag(FD->getLocation(), diag::ext_flexible_array_in_struct, 1600 FD->getName()); 1601 if (Record) 1602 Record->setHasFlexibleArrayMember(true); 1603 } 1604 } 1605 } 1606 /// A field cannot be an Objective-c object 1607 if (FDTy->isObjCInterfaceType()) { 1608 Diag(FD->getLocation(), diag::err_statically_allocated_object, 1609 FD->getName()); 1610 FD->setInvalidDecl(); 1611 EnclosingDecl->setInvalidDecl(); 1612 continue; 1613 } 1614 // Keep track of the number of named members. 1615 if (IdentifierInfo *II = FD->getIdentifier()) { 1616 // Detect duplicate member names. 1617 if (!FieldIDs.insert(II)) { 1618 Diag(FD->getLocation(), diag::err_duplicate_member, II->getName()); 1619 // Find the previous decl. 1620 SourceLocation PrevLoc; 1621 for (unsigned i = 0, e = RecFields.size(); ; ++i) { 1622 assert(i != e && "Didn't find previous def!"); 1623 if (RecFields[i]->getIdentifier() == II) { 1624 PrevLoc = RecFields[i]->getLocation(); 1625 break; 1626 } 1627 } 1628 Diag(PrevLoc, diag::err_previous_definition); 1629 FD->setInvalidDecl(); 1630 EnclosingDecl->setInvalidDecl(); 1631 continue; 1632 } 1633 ++NumNamedMembers; 1634 } 1635 } 1636 1637 // Okay, we successfully defined 'Record'. 1638 if (Record) { 1639 Record->defineBody(&RecFields[0], RecFields.size()); 1640 Consumer.HandleTagDeclDefinition(Record); 1641 } else { 1642 ObjCIvarDecl **ClsFields = reinterpret_cast<ObjCIvarDecl**>(&RecFields[0]); 1643 if (ObjCInterfaceDecl *ID = dyn_cast<ObjCInterfaceDecl>(EnclosingDecl)) 1644 ID->addInstanceVariablesToClass(ClsFields, RecFields.size(), RBrac); 1645 else if (ObjCImplementationDecl *IMPDecl = 1646 dyn_cast<ObjCImplementationDecl>(EnclosingDecl)) { 1647 assert(IMPDecl && "ActOnFields - missing ObjCImplementationDecl"); 1648 IMPDecl->ObjCAddInstanceVariablesToClassImpl(ClsFields, RecFields.size()); 1649 CheckImplementationIvars(IMPDecl, ClsFields, RecFields.size(), RBrac); 1650 } 1651 } 1652} 1653 1654Sema::DeclTy *Sema::ActOnEnumConstant(Scope *S, DeclTy *theEnumDecl, 1655 DeclTy *lastEnumConst, 1656 SourceLocation IdLoc, IdentifierInfo *Id, 1657 SourceLocation EqualLoc, ExprTy *val) { 1658 EnumDecl *TheEnumDecl = cast<EnumDecl>(static_cast<Decl*>(theEnumDecl)); 1659 EnumConstantDecl *LastEnumConst = 1660 cast_or_null<EnumConstantDecl>(static_cast<Decl*>(lastEnumConst)); 1661 Expr *Val = static_cast<Expr*>(val); 1662 1663 // The scope passed in may not be a decl scope. Zip up the scope tree until 1664 // we find one that is. 1665 while ((S->getFlags() & Scope::DeclScope) == 0) 1666 S = S->getParent(); 1667 1668 // Verify that there isn't already something declared with this name in this 1669 // scope. 1670 if (Decl *PrevDecl = LookupDecl(Id, Decl::IDNS_Ordinary, S)) { 1671 if (S->isDeclScope(PrevDecl)) { 1672 if (isa<EnumConstantDecl>(PrevDecl)) 1673 Diag(IdLoc, diag::err_redefinition_of_enumerator, Id->getName()); 1674 else 1675 Diag(IdLoc, diag::err_redefinition, Id->getName()); 1676 Diag(PrevDecl->getLocation(), diag::err_previous_definition); 1677 delete Val; 1678 return 0; 1679 } 1680 } 1681 1682 llvm::APSInt EnumVal(32); 1683 QualType EltTy; 1684 if (Val) { 1685 // Make sure to promote the operand type to int. 1686 UsualUnaryConversions(Val); 1687 1688 // C99 6.7.2.2p2: Make sure we have an integer constant expression. 1689 SourceLocation ExpLoc; 1690 if (!Val->isIntegerConstantExpr(EnumVal, Context, &ExpLoc)) { 1691 Diag(ExpLoc, diag::err_enum_value_not_integer_constant_expr, 1692 Id->getName()); 1693 delete Val; 1694 Val = 0; // Just forget about it. 1695 } else { 1696 EltTy = Val->getType(); 1697 } 1698 } 1699 1700 if (!Val) { 1701 if (LastEnumConst) { 1702 // Assign the last value + 1. 1703 EnumVal = LastEnumConst->getInitVal(); 1704 ++EnumVal; 1705 1706 // Check for overflow on increment. 1707 if (EnumVal < LastEnumConst->getInitVal()) 1708 Diag(IdLoc, diag::warn_enum_value_overflow); 1709 1710 EltTy = LastEnumConst->getType(); 1711 } else { 1712 // First value, set to zero. 1713 EltTy = Context.IntTy; 1714 EnumVal.zextOrTrunc(static_cast<uint32_t>(Context.getTypeSize(EltTy))); 1715 } 1716 } 1717 1718 EnumConstantDecl *New = 1719 EnumConstantDecl::Create(Context, TheEnumDecl, IdLoc, Id, EltTy, 1720 Val, EnumVal, 1721 LastEnumConst); 1722 1723 // Register this decl in the current scope stack. 1724 PushOnScopeChains(New, S); 1725 return New; 1726} 1727 1728void Sema::ActOnEnumBody(SourceLocation EnumLoc, DeclTy *EnumDeclX, 1729 DeclTy **Elements, unsigned NumElements) { 1730 EnumDecl *Enum = cast<EnumDecl>(static_cast<Decl*>(EnumDeclX)); 1731 assert(!Enum->isDefinition() && "Enum redefinitions can't reach here"); 1732 1733 // TODO: If the result value doesn't fit in an int, it must be a long or long 1734 // long value. ISO C does not support this, but GCC does as an extension, 1735 // emit a warning. 1736 unsigned IntWidth = Context.Target.getIntWidth(); 1737 1738 // Verify that all the values are okay, compute the size of the values, and 1739 // reverse the list. 1740 unsigned NumNegativeBits = 0; 1741 unsigned NumPositiveBits = 0; 1742 1743 // Keep track of whether all elements have type int. 1744 bool AllElementsInt = true; 1745 1746 EnumConstantDecl *EltList = 0; 1747 for (unsigned i = 0; i != NumElements; ++i) { 1748 EnumConstantDecl *ECD = 1749 cast_or_null<EnumConstantDecl>(static_cast<Decl*>(Elements[i])); 1750 if (!ECD) continue; // Already issued a diagnostic. 1751 1752 // If the enum value doesn't fit in an int, emit an extension warning. 1753 const llvm::APSInt &InitVal = ECD->getInitVal(); 1754 assert(InitVal.getBitWidth() >= IntWidth && 1755 "Should have promoted value to int"); 1756 if (InitVal.getBitWidth() > IntWidth) { 1757 llvm::APSInt V(InitVal); 1758 V.trunc(IntWidth); 1759 V.extend(InitVal.getBitWidth()); 1760 if (V != InitVal) 1761 Diag(ECD->getLocation(), diag::ext_enum_value_not_int, 1762 InitVal.toString()); 1763 } 1764 1765 // Keep track of the size of positive and negative values. 1766 if (InitVal.isUnsigned() || InitVal.isNonNegative()) 1767 NumPositiveBits = std::max(NumPositiveBits, 1768 (unsigned)InitVal.getActiveBits()); 1769 else 1770 NumNegativeBits = std::max(NumNegativeBits, 1771 (unsigned)InitVal.getMinSignedBits()); 1772 1773 // Keep track of whether every enum element has type int (very commmon). 1774 if (AllElementsInt) 1775 AllElementsInt = ECD->getType() == Context.IntTy; 1776 1777 ECD->setNextDeclarator(EltList); 1778 EltList = ECD; 1779 } 1780 1781 // Figure out the type that should be used for this enum. 1782 // FIXME: Support attribute(packed) on enums and -fshort-enums. 1783 QualType BestType; 1784 unsigned BestWidth; 1785 1786 if (NumNegativeBits) { 1787 // If there is a negative value, figure out the smallest integer type (of 1788 // int/long/longlong) that fits. 1789 if (NumNegativeBits <= IntWidth && NumPositiveBits < IntWidth) { 1790 BestType = Context.IntTy; 1791 BestWidth = IntWidth; 1792 } else { 1793 BestWidth = Context.Target.getLongWidth(); 1794 1795 if (NumNegativeBits <= BestWidth && NumPositiveBits < BestWidth) 1796 BestType = Context.LongTy; 1797 else { 1798 BestWidth = Context.Target.getLongLongWidth(); 1799 1800 if (NumNegativeBits > BestWidth || NumPositiveBits >= BestWidth) 1801 Diag(Enum->getLocation(), diag::warn_enum_too_large); 1802 BestType = Context.LongLongTy; 1803 } 1804 } 1805 } else { 1806 // If there is no negative value, figure out which of uint, ulong, ulonglong 1807 // fits. 1808 if (NumPositiveBits <= IntWidth) { 1809 BestType = Context.UnsignedIntTy; 1810 BestWidth = IntWidth; 1811 } else if (NumPositiveBits <= 1812 (BestWidth = Context.Target.getLongWidth())) { 1813 BestType = Context.UnsignedLongTy; 1814 } else { 1815 BestWidth = Context.Target.getLongLongWidth(); 1816 assert(NumPositiveBits <= BestWidth && 1817 "How could an initializer get larger than ULL?"); 1818 BestType = Context.UnsignedLongLongTy; 1819 } 1820 } 1821 1822 // Loop over all of the enumerator constants, changing their types to match 1823 // the type of the enum if needed. 1824 for (unsigned i = 0; i != NumElements; ++i) { 1825 EnumConstantDecl *ECD = 1826 cast_or_null<EnumConstantDecl>(static_cast<Decl*>(Elements[i])); 1827 if (!ECD) continue; // Already issued a diagnostic. 1828 1829 // Standard C says the enumerators have int type, but we allow, as an 1830 // extension, the enumerators to be larger than int size. If each 1831 // enumerator value fits in an int, type it as an int, otherwise type it the 1832 // same as the enumerator decl itself. This means that in "enum { X = 1U }" 1833 // that X has type 'int', not 'unsigned'. 1834 if (ECD->getType() == Context.IntTy) { 1835 // Make sure the init value is signed. 1836 llvm::APSInt IV = ECD->getInitVal(); 1837 IV.setIsSigned(true); 1838 ECD->setInitVal(IV); 1839 continue; // Already int type. 1840 } 1841 1842 // Determine whether the value fits into an int. 1843 llvm::APSInt InitVal = ECD->getInitVal(); 1844 bool FitsInInt; 1845 if (InitVal.isUnsigned() || !InitVal.isNegative()) 1846 FitsInInt = InitVal.getActiveBits() < IntWidth; 1847 else 1848 FitsInInt = InitVal.getMinSignedBits() <= IntWidth; 1849 1850 // If it fits into an integer type, force it. Otherwise force it to match 1851 // the enum decl type. 1852 QualType NewTy; 1853 unsigned NewWidth; 1854 bool NewSign; 1855 if (FitsInInt) { 1856 NewTy = Context.IntTy; 1857 NewWidth = IntWidth; 1858 NewSign = true; 1859 } else if (ECD->getType() == BestType) { 1860 // Already the right type! 1861 continue; 1862 } else { 1863 NewTy = BestType; 1864 NewWidth = BestWidth; 1865 NewSign = BestType->isSignedIntegerType(); 1866 } 1867 1868 // Adjust the APSInt value. 1869 InitVal.extOrTrunc(NewWidth); 1870 InitVal.setIsSigned(NewSign); 1871 ECD->setInitVal(InitVal); 1872 1873 // Adjust the Expr initializer and type. 1874 ECD->setInitExpr(new ImplicitCastExpr(NewTy, ECD->getInitExpr())); 1875 ECD->setType(NewTy); 1876 } 1877 1878 Enum->defineElements(EltList, BestType); 1879 Consumer.HandleTagDeclDefinition(Enum); 1880} 1881 1882Sema::DeclTy *Sema::ActOnFileScopeAsmDecl(SourceLocation Loc, 1883 ExprTy *expr) { 1884 StringLiteral *AsmString = cast<StringLiteral>((Expr*)expr); 1885 1886 return FileScopeAsmDecl::Create(Context, Loc, AsmString); 1887} 1888 1889Sema::DeclTy* Sema::ActOnLinkageSpec(SourceLocation Loc, 1890 SourceLocation LBrace, 1891 SourceLocation RBrace, 1892 const char *Lang, 1893 unsigned StrSize, 1894 DeclTy *D) { 1895 LinkageSpecDecl::LanguageIDs Language; 1896 Decl *dcl = static_cast<Decl *>(D); 1897 if (strncmp(Lang, "\"C\"", StrSize) == 0) 1898 Language = LinkageSpecDecl::lang_c; 1899 else if (strncmp(Lang, "\"C++\"", StrSize) == 0) 1900 Language = LinkageSpecDecl::lang_cxx; 1901 else { 1902 Diag(Loc, diag::err_bad_language); 1903 return 0; 1904 } 1905 1906 // FIXME: Add all the various semantics of linkage specifications 1907 return LinkageSpecDecl::Create(Context, Loc, Language, dcl); 1908} 1909 1910void Sema::HandleDeclAttribute(Decl *New, AttributeList *Attr) { 1911 1912 switch (Attr->getKind()) { 1913 case AttributeList::AT_vector_size: 1914 if (ValueDecl *vDecl = dyn_cast<ValueDecl>(New)) { 1915 QualType newType = HandleVectorTypeAttribute(vDecl->getType(), Attr); 1916 if (!newType.isNull()) // install the new vector type into the decl 1917 vDecl->setType(newType); 1918 } 1919 if (TypedefDecl *tDecl = dyn_cast<TypedefDecl>(New)) { 1920 QualType newType = HandleVectorTypeAttribute(tDecl->getUnderlyingType(), 1921 Attr); 1922 if (!newType.isNull()) // install the new vector type into the decl 1923 tDecl->setUnderlyingType(newType); 1924 } 1925 break; 1926 case AttributeList::AT_ocu_vector_type: 1927 if (TypedefDecl *tDecl = dyn_cast<TypedefDecl>(New)) 1928 HandleOCUVectorTypeAttribute(tDecl, Attr); 1929 else 1930 Diag(Attr->getLoc(), 1931 diag::err_typecheck_ocu_vector_not_typedef); 1932 break; 1933 case AttributeList::AT_address_space: 1934 if (TypedefDecl *tDecl = dyn_cast<TypedefDecl>(New)) { 1935 QualType newType = HandleAddressSpaceTypeAttribute( 1936 tDecl->getUnderlyingType(), 1937 Attr); 1938 tDecl->setUnderlyingType(newType); 1939 } else if (ValueDecl *vDecl = dyn_cast<ValueDecl>(New)) { 1940 QualType newType = HandleAddressSpaceTypeAttribute(vDecl->getType(), 1941 Attr); 1942 // install the new addr spaced type into the decl 1943 vDecl->setType(newType); 1944 } 1945 break; 1946 case AttributeList::AT_deprecated: 1947 HandleDeprecatedAttribute(New, Attr); 1948 break; 1949 case AttributeList::AT_visibility: 1950 HandleVisibilityAttribute(New, Attr); 1951 break; 1952 case AttributeList::AT_weak: 1953 HandleWeakAttribute(New, Attr); 1954 break; 1955 case AttributeList::AT_dllimport: 1956 HandleDLLImportAttribute(New, Attr); 1957 break; 1958 case AttributeList::AT_dllexport: 1959 HandleDLLExportAttribute(New, Attr); 1960 break; 1961 case AttributeList::AT_nothrow: 1962 HandleNothrowAttribute(New, Attr); 1963 break; 1964 case AttributeList::AT_stdcall: 1965 HandleStdCallAttribute(New, Attr); 1966 break; 1967 case AttributeList::AT_fastcall: 1968 HandleFastCallAttribute(New, Attr); 1969 break; 1970 case AttributeList::AT_aligned: 1971 HandleAlignedAttribute(New, Attr); 1972 break; 1973 case AttributeList::AT_packed: 1974 HandlePackedAttribute(New, Attr); 1975 break; 1976 case AttributeList::AT_annotate: 1977 HandleAnnotateAttribute(New, Attr); 1978 break; 1979 case AttributeList::AT_noreturn: 1980 HandleNoReturnAttribute(New, Attr); 1981 break; 1982 case AttributeList::AT_format: 1983 HandleFormatAttribute(New, Attr); 1984 break; 1985 default: 1986#if 0 1987 // TODO: when we have the full set of attributes, warn about unknown ones. 1988 Diag(Attr->getLoc(), diag::warn_attribute_ignored, 1989 Attr->getName()->getName()); 1990#endif 1991 break; 1992 } 1993} 1994 1995void Sema::HandleDeclAttributes(Decl *New, AttributeList *declspec_prefix, 1996 AttributeList *declarator_postfix) { 1997 while (declspec_prefix) { 1998 HandleDeclAttribute(New, declspec_prefix); 1999 declspec_prefix = declspec_prefix->getNext(); 2000 } 2001 while (declarator_postfix) { 2002 HandleDeclAttribute(New, declarator_postfix); 2003 declarator_postfix = declarator_postfix->getNext(); 2004 } 2005} 2006 2007void Sema::HandleOCUVectorTypeAttribute(TypedefDecl *tDecl, 2008 AttributeList *rawAttr) { 2009 QualType curType = tDecl->getUnderlyingType(); 2010 // check the attribute arguments. 2011 if (rawAttr->getNumArgs() != 1) { 2012 Diag(rawAttr->getLoc(), diag::err_attribute_wrong_number_arguments, 2013 std::string("1")); 2014 return; 2015 } 2016 Expr *sizeExpr = static_cast<Expr *>(rawAttr->getArg(0)); 2017 llvm::APSInt vecSize(32); 2018 if (!sizeExpr->isIntegerConstantExpr(vecSize, Context)) { 2019 Diag(rawAttr->getLoc(), diag::err_attribute_argument_not_int, 2020 "ocu_vector_type", sizeExpr->getSourceRange()); 2021 return; 2022 } 2023 // unlike gcc's vector_size attribute, we do not allow vectors to be defined 2024 // in conjunction with complex types (pointers, arrays, functions, etc.). 2025 Type *canonType = curType.getCanonicalType().getTypePtr(); 2026 if (!(canonType->isIntegerType() || canonType->isRealFloatingType())) { 2027 Diag(rawAttr->getLoc(), diag::err_attribute_invalid_vector_type, 2028 curType.getCanonicalType().getAsString()); 2029 return; 2030 } 2031 // unlike gcc's vector_size attribute, the size is specified as the 2032 // number of elements, not the number of bytes. 2033 unsigned vectorSize = static_cast<unsigned>(vecSize.getZExtValue()); 2034 2035 if (vectorSize == 0) { 2036 Diag(rawAttr->getLoc(), diag::err_attribute_zero_size, 2037 sizeExpr->getSourceRange()); 2038 return; 2039 } 2040 // Instantiate/Install the vector type, the number of elements is > 0. 2041 tDecl->setUnderlyingType(Context.getOCUVectorType(curType, vectorSize)); 2042 // Remember this typedef decl, we will need it later for diagnostics. 2043 OCUVectorDecls.push_back(tDecl); 2044} 2045 2046QualType Sema::HandleVectorTypeAttribute(QualType curType, 2047 AttributeList *rawAttr) { 2048 // check the attribute arugments. 2049 if (rawAttr->getNumArgs() != 1) { 2050 Diag(rawAttr->getLoc(), diag::err_attribute_wrong_number_arguments, 2051 std::string("1")); 2052 return QualType(); 2053 } 2054 Expr *sizeExpr = static_cast<Expr *>(rawAttr->getArg(0)); 2055 llvm::APSInt vecSize(32); 2056 if (!sizeExpr->isIntegerConstantExpr(vecSize, Context)) { 2057 Diag(rawAttr->getLoc(), diag::err_attribute_argument_not_int, 2058 "vector_size", sizeExpr->getSourceRange()); 2059 return QualType(); 2060 } 2061 // navigate to the base type - we need to provide for vector pointers, 2062 // vector arrays, and functions returning vectors. 2063 Type *canonType = curType.getCanonicalType().getTypePtr(); 2064 2065 if (canonType->isPointerType() || canonType->isArrayType() || 2066 canonType->isFunctionType()) { 2067 assert(0 && "HandleVector(): Complex type construction unimplemented"); 2068 /* FIXME: rebuild the type from the inside out, vectorizing the inner type. 2069 do { 2070 if (PointerType *PT = dyn_cast<PointerType>(canonType)) 2071 canonType = PT->getPointeeType().getTypePtr(); 2072 else if (ArrayType *AT = dyn_cast<ArrayType>(canonType)) 2073 canonType = AT->getElementType().getTypePtr(); 2074 else if (FunctionType *FT = dyn_cast<FunctionType>(canonType)) 2075 canonType = FT->getResultType().getTypePtr(); 2076 } while (canonType->isPointerType() || canonType->isArrayType() || 2077 canonType->isFunctionType()); 2078 */ 2079 } 2080 // the base type must be integer or float. 2081 if (!(canonType->isIntegerType() || canonType->isRealFloatingType())) { 2082 Diag(rawAttr->getLoc(), diag::err_attribute_invalid_vector_type, 2083 curType.getCanonicalType().getAsString()); 2084 return QualType(); 2085 } 2086 unsigned typeSize = static_cast<unsigned>(Context.getTypeSize(curType)); 2087 // vecSize is specified in bytes - convert to bits. 2088 unsigned vectorSize = static_cast<unsigned>(vecSize.getZExtValue() * 8); 2089 2090 // the vector size needs to be an integral multiple of the type size. 2091 if (vectorSize % typeSize) { 2092 Diag(rawAttr->getLoc(), diag::err_attribute_invalid_size, 2093 sizeExpr->getSourceRange()); 2094 return QualType(); 2095 } 2096 if (vectorSize == 0) { 2097 Diag(rawAttr->getLoc(), diag::err_attribute_zero_size, 2098 sizeExpr->getSourceRange()); 2099 return QualType(); 2100 } 2101 // Instantiate the vector type, the number of elements is > 0, and not 2102 // required to be a power of 2, unlike GCC. 2103 return Context.getVectorType(curType, vectorSize/typeSize); 2104} 2105 2106void Sema::HandlePackedAttribute(Decl *d, AttributeList *rawAttr) { 2107 // check the attribute arguments. 2108 if (rawAttr->getNumArgs() > 0) { 2109 Diag(rawAttr->getLoc(), diag::err_attribute_wrong_number_arguments, 2110 std::string("0")); 2111 return; 2112 } 2113 2114 if (TagDecl *TD = dyn_cast<TagDecl>(d)) 2115 TD->addAttr(new PackedAttr); 2116 else if (FieldDecl *FD = dyn_cast<FieldDecl>(d)) { 2117 // If the alignment is less than or equal to 8 bits, the packed attribute 2118 // has no effect. 2119 if (Context.getTypeAlign(FD->getType()) <= 8) 2120 Diag(rawAttr->getLoc(), 2121 diag::warn_attribute_ignored_for_field_of_type, 2122 rawAttr->getName()->getName(), FD->getType().getAsString()); 2123 else 2124 FD->addAttr(new PackedAttr); 2125 } else 2126 Diag(rawAttr->getLoc(), diag::warn_attribute_ignored, 2127 rawAttr->getName()->getName()); 2128} 2129 2130void Sema::HandleNoReturnAttribute(Decl *d, AttributeList *rawAttr) { 2131 // check the attribute arguments. 2132 if (rawAttr->getNumArgs() != 0) { 2133 Diag(rawAttr->getLoc(), diag::err_attribute_wrong_number_arguments, 2134 std::string("0")); 2135 return; 2136 } 2137 2138 FunctionDecl *Fn = dyn_cast<FunctionDecl>(d); 2139 2140 if (!Fn) { 2141 Diag(rawAttr->getLoc(), diag::warn_attribute_wrong_decl_type, 2142 "noreturn", "function"); 2143 return; 2144 } 2145 2146 d->addAttr(new NoReturnAttr()); 2147} 2148 2149void Sema::HandleDeprecatedAttribute(Decl *d, AttributeList *rawAttr) { 2150 // check the attribute arguments. 2151 if (rawAttr->getNumArgs() != 0) { 2152 Diag(rawAttr->getLoc(), diag::err_attribute_wrong_number_arguments, 2153 std::string("0")); 2154 return; 2155 } 2156 2157 d->addAttr(new DeprecatedAttr()); 2158} 2159 2160void Sema::HandleVisibilityAttribute(Decl *d, AttributeList *rawAttr) { 2161 // check the attribute arguments. 2162 if (rawAttr->getNumArgs() != 1) { 2163 Diag(rawAttr->getLoc(), diag::err_attribute_wrong_number_arguments, 2164 std::string("1")); 2165 return; 2166 } 2167 2168 Expr *Arg = static_cast<Expr*>(rawAttr->getArg(0)); 2169 Arg = Arg->IgnoreParenCasts(); 2170 StringLiteral *Str = dyn_cast<StringLiteral>(Arg); 2171 2172 if (Str == 0 || Str->isWide()) { 2173 Diag(rawAttr->getLoc(), diag::err_attribute_argument_n_not_string, 2174 "visibility", std::string("1")); 2175 return; 2176 } 2177 2178 const char *TypeStr = Str->getStrData(); 2179 unsigned TypeLen = Str->getByteLength(); 2180 llvm::GlobalValue::VisibilityTypes type; 2181 2182 if (TypeLen == 7 && !memcmp(TypeStr, "default", 7)) 2183 type = llvm::GlobalValue::DefaultVisibility; 2184 else if (TypeLen == 6 && !memcmp(TypeStr, "hidden", 6)) 2185 type = llvm::GlobalValue::HiddenVisibility; 2186 else if (TypeLen == 8 && !memcmp(TypeStr, "internal", 8)) 2187 type = llvm::GlobalValue::HiddenVisibility; // FIXME 2188 else if (TypeLen == 9 && !memcmp(TypeStr, "protected", 9)) 2189 type = llvm::GlobalValue::ProtectedVisibility; 2190 else { 2191 Diag(rawAttr->getLoc(), diag::warn_attribute_type_not_supported, 2192 "visibility", TypeStr); 2193 return; 2194 } 2195 2196 d->addAttr(new VisibilityAttr(type)); 2197} 2198 2199void Sema::HandleWeakAttribute(Decl *d, AttributeList *rawAttr) { 2200 // check the attribute arguments. 2201 if (rawAttr->getNumArgs() != 0) { 2202 Diag(rawAttr->getLoc(), diag::err_attribute_wrong_number_arguments, 2203 std::string("0")); 2204 return; 2205 } 2206 2207 d->addAttr(new WeakAttr()); 2208} 2209 2210void Sema::HandleDLLImportAttribute(Decl *d, AttributeList *rawAttr) { 2211 // check the attribute arguments. 2212 if (rawAttr->getNumArgs() != 0) { 2213 Diag(rawAttr->getLoc(), diag::err_attribute_wrong_number_arguments, 2214 std::string("0")); 2215 return; 2216 } 2217 2218 d->addAttr(new DLLImportAttr()); 2219} 2220 2221void Sema::HandleDLLExportAttribute(Decl *d, AttributeList *rawAttr) { 2222 // check the attribute arguments. 2223 if (rawAttr->getNumArgs() != 0) { 2224 Diag(rawAttr->getLoc(), diag::err_attribute_wrong_number_arguments, 2225 std::string("0")); 2226 return; 2227 } 2228 2229 d->addAttr(new DLLExportAttr()); 2230} 2231 2232void Sema::HandleStdCallAttribute(Decl *d, AttributeList *rawAttr) { 2233 // check the attribute arguments. 2234 if (rawAttr->getNumArgs() != 0) { 2235 Diag(rawAttr->getLoc(), diag::err_attribute_wrong_number_arguments, 2236 std::string("0")); 2237 return; 2238 } 2239 2240 d->addAttr(new StdCallAttr()); 2241} 2242 2243void Sema::HandleFastCallAttribute(Decl *d, AttributeList *rawAttr) { 2244 // check the attribute arguments. 2245 if (rawAttr->getNumArgs() != 0) { 2246 Diag(rawAttr->getLoc(), diag::err_attribute_wrong_number_arguments, 2247 std::string("0")); 2248 return; 2249 } 2250 2251 d->addAttr(new FastCallAttr()); 2252} 2253 2254void Sema::HandleNothrowAttribute(Decl *d, AttributeList *rawAttr) { 2255 // check the attribute arguments. 2256 if (rawAttr->getNumArgs() != 0) { 2257 Diag(rawAttr->getLoc(), diag::err_attribute_wrong_number_arguments, 2258 std::string("0")); 2259 return; 2260 } 2261 2262 d->addAttr(new NoThrowAttr()); 2263} 2264 2265static const FunctionTypeProto *getFunctionProto(Decl *d) { 2266 ValueDecl *decl = dyn_cast<ValueDecl>(d); 2267 if (!decl) return 0; 2268 2269 QualType Ty = decl->getType(); 2270 2271 if (Ty->isFunctionPointerType()) { 2272 const PointerType *PtrTy = Ty->getAsPointerType(); 2273 Ty = PtrTy->getPointeeType(); 2274 } 2275 2276 if (const FunctionType *FnTy = Ty->getAsFunctionType()) 2277 return dyn_cast<FunctionTypeProto>(FnTy->getAsFunctionType()); 2278 2279 return 0; 2280} 2281 2282 2283/// Handle __attribute__((format(type,idx,firstarg))) attributes 2284/// based on http://gcc.gnu.org/onlinedocs/gcc/Function-Attributes.html 2285void Sema::HandleFormatAttribute(Decl *d, AttributeList *rawAttr) { 2286 2287 if (!rawAttr->getParameterName()) { 2288 Diag(rawAttr->getLoc(), diag::err_attribute_argument_n_not_string, 2289 "format", std::string("1")); 2290 return; 2291 } 2292 2293 if (rawAttr->getNumArgs() != 2) { 2294 Diag(rawAttr->getLoc(), diag::err_attribute_wrong_number_arguments, 2295 std::string("3")); 2296 return; 2297 } 2298 2299 // GCC ignores the format attribute on K&R style function 2300 // prototypes, so we ignore it as well 2301 const FunctionTypeProto *proto = getFunctionProto(d); 2302 2303 if (!proto) { 2304 Diag(rawAttr->getLoc(), diag::warn_attribute_wrong_decl_type, 2305 "format", "function"); 2306 return; 2307 } 2308 2309 // FIXME: in C++ the implicit 'this' function parameter also counts. 2310 // this is needed in order to be compatible with GCC 2311 // the index must start in 1 and the limit is numargs+1 2312 unsigned NumArgs = proto->getNumArgs(); 2313 unsigned FirstIdx = 1; 2314 2315 const char *Format = rawAttr->getParameterName()->getName(); 2316 unsigned FormatLen = rawAttr->getParameterName()->getLength(); 2317 2318 // Normalize the argument, __foo__ becomes foo. 2319 if (FormatLen > 4 && Format[0] == '_' && Format[1] == '_' && 2320 Format[FormatLen - 2] == '_' && Format[FormatLen - 1] == '_') { 2321 Format += 2; 2322 FormatLen -= 4; 2323 } 2324 2325 if (!((FormatLen == 5 && !memcmp(Format, "scanf", 5)) 2326 || (FormatLen == 6 && !memcmp(Format, "printf", 6)) 2327 || (FormatLen == 7 && !memcmp(Format, "strfmon", 7)) 2328 || (FormatLen == 8 && !memcmp(Format, "strftime", 8)))) { 2329 Diag(rawAttr->getLoc(), diag::warn_attribute_type_not_supported, 2330 "format", rawAttr->getParameterName()->getName()); 2331 return; 2332 } 2333 2334 // checks for the 2nd argument 2335 Expr *IdxExpr = static_cast<Expr *>(rawAttr->getArg(0)); 2336 llvm::APSInt Idx(Context.getTypeSize(IdxExpr->getType())); 2337 if (!IdxExpr->isIntegerConstantExpr(Idx, Context)) { 2338 Diag(rawAttr->getLoc(), diag::err_attribute_argument_n_not_int, 2339 "format", std::string("2"), IdxExpr->getSourceRange()); 2340 return; 2341 } 2342 2343 if (Idx.getZExtValue() < FirstIdx || Idx.getZExtValue() > NumArgs) { 2344 Diag(rawAttr->getLoc(), diag::err_attribute_argument_out_of_bounds, 2345 "format", std::string("2"), IdxExpr->getSourceRange()); 2346 return; 2347 } 2348 2349 // make sure the format string is really a string 2350 QualType Ty = proto->getArgType(Idx.getZExtValue()-1); 2351 if (!Ty->isPointerType() || 2352 !Ty->getAsPointerType()->getPointeeType()->isCharType()) { 2353 Diag(rawAttr->getLoc(), diag::err_format_attribute_not_string, 2354 IdxExpr->getSourceRange()); 2355 return; 2356 } 2357 2358 2359 // check the 3rd argument 2360 Expr *FirstArgExpr = static_cast<Expr *>(rawAttr->getArg(1)); 2361 llvm::APSInt FirstArg(Context.getTypeSize(FirstArgExpr->getType())); 2362 if (!FirstArgExpr->isIntegerConstantExpr(FirstArg, Context)) { 2363 Diag(rawAttr->getLoc(), diag::err_attribute_argument_n_not_int, 2364 "format", std::string("3"), FirstArgExpr->getSourceRange()); 2365 return; 2366 } 2367 2368 // check if the function is variadic if the 3rd argument non-zero 2369 if (FirstArg != 0) { 2370 if (proto->isVariadic()) { 2371 ++NumArgs; // +1 for ... 2372 } else { 2373 Diag(d->getLocation(), diag::err_format_attribute_requires_variadic); 2374 return; 2375 } 2376 } 2377 2378 // strftime requires FirstArg to be 0 because it doesn't read from any variable 2379 // the input is just the current time + the format string 2380 if (FormatLen == 8 && !memcmp(Format, "strftime", 8)) { 2381 if (FirstArg != 0) { 2382 Diag(rawAttr->getLoc(), diag::err_format_strftime_third_parameter, 2383 FirstArgExpr->getSourceRange()); 2384 return; 2385 } 2386 // if 0 it disables parameter checking (to use with e.g. va_list) 2387 } else if (FirstArg != 0 && FirstArg != NumArgs) { 2388 Diag(rawAttr->getLoc(), diag::err_attribute_argument_out_of_bounds, 2389 "format", std::string("3"), FirstArgExpr->getSourceRange()); 2390 return; 2391 } 2392 2393 d->addAttr(new FormatAttr(std::string(Format, FormatLen), 2394 Idx.getZExtValue(), FirstArg.getZExtValue())); 2395} 2396 2397void Sema::HandleAnnotateAttribute(Decl *d, AttributeList *rawAttr) { 2398 // check the attribute arguments. 2399 if (rawAttr->getNumArgs() != 1) { 2400 Diag(rawAttr->getLoc(), diag::err_attribute_wrong_number_arguments, 2401 std::string("1")); 2402 return; 2403 } 2404 Expr *argExpr = static_cast<Expr *>(rawAttr->getArg(0)); 2405 StringLiteral *SE = dyn_cast<StringLiteral>(argExpr); 2406 2407 // Make sure that there is a string literal as the annotation's single 2408 // argument. 2409 if (!SE) { 2410 Diag(rawAttr->getLoc(), diag::err_attribute_annotate_no_string); 2411 return; 2412 } 2413 d->addAttr(new AnnotateAttr(std::string(SE->getStrData(), 2414 SE->getByteLength()))); 2415} 2416 2417void Sema::HandleAlignedAttribute(Decl *d, AttributeList *rawAttr) 2418{ 2419 // check the attribute arguments. 2420 if (rawAttr->getNumArgs() > 1) { 2421 Diag(rawAttr->getLoc(), diag::err_attribute_wrong_number_arguments, 2422 std::string("1")); 2423 return; 2424 } 2425 2426 unsigned Align = 0; 2427 2428 if (rawAttr->getNumArgs() == 0) { 2429 // FIXME: This should be the target specific maximum alignment. 2430 // (For now we just use 128 bits which is the maximum on X86. 2431 Align = 128; 2432 return; 2433 } else { 2434 Expr *alignmentExpr = static_cast<Expr *>(rawAttr->getArg(0)); 2435 llvm::APSInt alignment(32); 2436 if (!alignmentExpr->isIntegerConstantExpr(alignment, Context)) { 2437 Diag(rawAttr->getLoc(), diag::err_attribute_argument_not_int, 2438 "aligned", alignmentExpr->getSourceRange()); 2439 return; 2440 } 2441 2442 Align = alignment.getZExtValue() * 8; 2443 } 2444 2445 d->addAttr(new AlignedAttr(Align)); 2446} 2447