SemaExpr.cpp revision 48218c60d6b53b7880917d1366ee716dec2145ca
1//===--- SemaExpr.cpp - Semantic Analysis for Expressions -----------------===// 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 expressions. 11// 12//===----------------------------------------------------------------------===// 13 14#include "clang/Sema/SemaInternal.h" 15#include "clang/Sema/Initialization.h" 16#include "clang/Sema/Lookup.h" 17#include "clang/Sema/AnalysisBasedWarnings.h" 18#include "clang/AST/ASTContext.h" 19#include "clang/AST/ASTMutationListener.h" 20#include "clang/AST/CXXInheritance.h" 21#include "clang/AST/DeclObjC.h" 22#include "clang/AST/DeclTemplate.h" 23#include "clang/AST/EvaluatedExprVisitor.h" 24#include "clang/AST/Expr.h" 25#include "clang/AST/ExprCXX.h" 26#include "clang/AST/ExprObjC.h" 27#include "clang/AST/RecursiveASTVisitor.h" 28#include "clang/AST/TypeLoc.h" 29#include "clang/Basic/PartialDiagnostic.h" 30#include "clang/Basic/SourceManager.h" 31#include "clang/Basic/TargetInfo.h" 32#include "clang/Lex/LiteralSupport.h" 33#include "clang/Lex/Preprocessor.h" 34#include "clang/Sema/DeclSpec.h" 35#include "clang/Sema/Designator.h" 36#include "clang/Sema/Scope.h" 37#include "clang/Sema/ScopeInfo.h" 38#include "clang/Sema/ParsedTemplate.h" 39#include "clang/Sema/Template.h" 40using namespace clang; 41using namespace sema; 42 43 44/// \brief Determine whether the use of this declaration is valid, and 45/// emit any corresponding diagnostics. 46/// 47/// This routine diagnoses various problems with referencing 48/// declarations that can occur when using a declaration. For example, 49/// it might warn if a deprecated or unavailable declaration is being 50/// used, or produce an error (and return true) if a C++0x deleted 51/// function is being used. 52/// 53/// If IgnoreDeprecated is set to true, this should not warn about deprecated 54/// decls. 55/// 56/// \returns true if there was an error (this declaration cannot be 57/// referenced), false otherwise. 58/// 59bool Sema::DiagnoseUseOfDecl(NamedDecl *D, SourceLocation Loc, 60 const ObjCInterfaceDecl *UnknownObjCClass) { 61 if (getLangOptions().CPlusPlus && isa<FunctionDecl>(D)) { 62 // If there were any diagnostics suppressed by template argument deduction, 63 // emit them now. 64 llvm::DenseMap<Decl *, llvm::SmallVector<PartialDiagnosticAt, 1> >::iterator 65 Pos = SuppressedDiagnostics.find(D->getCanonicalDecl()); 66 if (Pos != SuppressedDiagnostics.end()) { 67 llvm::SmallVectorImpl<PartialDiagnosticAt> &Suppressed = Pos->second; 68 for (unsigned I = 0, N = Suppressed.size(); I != N; ++I) 69 Diag(Suppressed[I].first, Suppressed[I].second); 70 71 // Clear out the list of suppressed diagnostics, so that we don't emit 72 // them again for this specialization. However, we don't obsolete this 73 // entry from the table, because we want to avoid ever emitting these 74 // diagnostics again. 75 Suppressed.clear(); 76 } 77 } 78 79 // See if this is an auto-typed variable whose initializer we are parsing. 80 if (ParsingInitForAutoVars.count(D)) { 81 Diag(Loc, diag::err_auto_variable_cannot_appear_in_own_initializer) 82 << D->getDeclName(); 83 return true; 84 } 85 86 // See if this is a deleted function. 87 if (FunctionDecl *FD = dyn_cast<FunctionDecl>(D)) { 88 if (FD->isDeleted()) { 89 Diag(Loc, diag::err_deleted_function_use); 90 Diag(D->getLocation(), diag::note_unavailable_here) << 1 << true; 91 return true; 92 } 93 } 94 95 // See if this declaration is unavailable or deprecated. 96 std::string Message; 97 switch (D->getAvailability(&Message)) { 98 case AR_Available: 99 case AR_NotYetIntroduced: 100 break; 101 102 case AR_Deprecated: 103 EmitDeprecationWarning(D, Message, Loc, UnknownObjCClass); 104 break; 105 106 case AR_Unavailable: 107 if (cast<Decl>(CurContext)->getAvailability() != AR_Unavailable) { 108 if (Message.empty()) { 109 if (!UnknownObjCClass) 110 Diag(Loc, diag::err_unavailable) << D->getDeclName(); 111 else 112 Diag(Loc, diag::warn_unavailable_fwdclass_message) 113 << D->getDeclName(); 114 } 115 else 116 Diag(Loc, diag::err_unavailable_message) 117 << D->getDeclName() << Message; 118 Diag(D->getLocation(), diag::note_unavailable_here) 119 << isa<FunctionDecl>(D) << false; 120 } 121 break; 122 } 123 124 // Warn if this is used but marked unused. 125 if (D->hasAttr<UnusedAttr>()) 126 Diag(Loc, diag::warn_used_but_marked_unused) << D->getDeclName(); 127 128 return false; 129} 130 131/// \brief Retrieve the message suffix that should be added to a 132/// diagnostic complaining about the given function being deleted or 133/// unavailable. 134std::string Sema::getDeletedOrUnavailableSuffix(const FunctionDecl *FD) { 135 // FIXME: C++0x implicitly-deleted special member functions could be 136 // detected here so that we could improve diagnostics to say, e.g., 137 // "base class 'A' had a deleted copy constructor". 138 if (FD->isDeleted()) 139 return std::string(); 140 141 std::string Message; 142 if (FD->getAvailability(&Message)) 143 return ": " + Message; 144 145 return std::string(); 146} 147 148/// DiagnoseSentinelCalls - This routine checks on method dispatch calls 149/// (and other functions in future), which have been declared with sentinel 150/// attribute. It warns if call does not have the sentinel argument. 151/// 152void Sema::DiagnoseSentinelCalls(NamedDecl *D, SourceLocation Loc, 153 Expr **Args, unsigned NumArgs) { 154 const SentinelAttr *attr = D->getAttr<SentinelAttr>(); 155 if (!attr) 156 return; 157 158 // FIXME: In C++0x, if any of the arguments are parameter pack 159 // expansions, we can't check for the sentinel now. 160 int sentinelPos = attr->getSentinel(); 161 int nullPos = attr->getNullPos(); 162 163 // FIXME. ObjCMethodDecl and FunctionDecl need be derived from the same common 164 // base class. Then we won't be needing two versions of the same code. 165 unsigned int i = 0; 166 bool warnNotEnoughArgs = false; 167 int isMethod = 0; 168 if (ObjCMethodDecl *MD = dyn_cast<ObjCMethodDecl>(D)) { 169 // skip over named parameters. 170 ObjCMethodDecl::param_iterator P, E = MD->param_end(); 171 for (P = MD->param_begin(); (P != E && i < NumArgs); ++P) { 172 if (nullPos) 173 --nullPos; 174 else 175 ++i; 176 } 177 warnNotEnoughArgs = (P != E || i >= NumArgs); 178 isMethod = 1; 179 } else if (FunctionDecl *FD = dyn_cast<FunctionDecl>(D)) { 180 // skip over named parameters. 181 ObjCMethodDecl::param_iterator P, E = FD->param_end(); 182 for (P = FD->param_begin(); (P != E && i < NumArgs); ++P) { 183 if (nullPos) 184 --nullPos; 185 else 186 ++i; 187 } 188 warnNotEnoughArgs = (P != E || i >= NumArgs); 189 } else if (VarDecl *V = dyn_cast<VarDecl>(D)) { 190 // block or function pointer call. 191 QualType Ty = V->getType(); 192 if (Ty->isBlockPointerType() || Ty->isFunctionPointerType()) { 193 const FunctionType *FT = Ty->isFunctionPointerType() 194 ? Ty->getAs<PointerType>()->getPointeeType()->getAs<FunctionType>() 195 : Ty->getAs<BlockPointerType>()->getPointeeType()->getAs<FunctionType>(); 196 if (const FunctionProtoType *Proto = dyn_cast<FunctionProtoType>(FT)) { 197 unsigned NumArgsInProto = Proto->getNumArgs(); 198 unsigned k; 199 for (k = 0; (k != NumArgsInProto && i < NumArgs); k++) { 200 if (nullPos) 201 --nullPos; 202 else 203 ++i; 204 } 205 warnNotEnoughArgs = (k != NumArgsInProto || i >= NumArgs); 206 } 207 if (Ty->isBlockPointerType()) 208 isMethod = 2; 209 } else 210 return; 211 } else 212 return; 213 214 if (warnNotEnoughArgs) { 215 Diag(Loc, diag::warn_not_enough_argument) << D->getDeclName(); 216 Diag(D->getLocation(), diag::note_sentinel_here) << isMethod; 217 return; 218 } 219 int sentinel = i; 220 while (sentinelPos > 0 && i < NumArgs-1) { 221 --sentinelPos; 222 ++i; 223 } 224 if (sentinelPos > 0) { 225 Diag(Loc, diag::warn_not_enough_argument) << D->getDeclName(); 226 Diag(D->getLocation(), diag::note_sentinel_here) << isMethod; 227 return; 228 } 229 while (i < NumArgs-1) { 230 ++i; 231 ++sentinel; 232 } 233 Expr *sentinelExpr = Args[sentinel]; 234 if (!sentinelExpr) return; 235 if (sentinelExpr->isTypeDependent()) return; 236 if (sentinelExpr->isValueDependent()) return; 237 238 // nullptr_t is always treated as null. 239 if (sentinelExpr->getType()->isNullPtrType()) return; 240 241 if (sentinelExpr->getType()->isAnyPointerType() && 242 sentinelExpr->IgnoreParenCasts()->isNullPointerConstant(Context, 243 Expr::NPC_ValueDependentIsNull)) 244 return; 245 246 // Unfortunately, __null has type 'int'. 247 if (isa<GNUNullExpr>(sentinelExpr)) return; 248 249 Diag(Loc, diag::warn_missing_sentinel) << isMethod; 250 Diag(D->getLocation(), diag::note_sentinel_here) << isMethod; 251} 252 253SourceRange Sema::getExprRange(ExprTy *E) const { 254 Expr *Ex = (Expr *)E; 255 return Ex? Ex->getSourceRange() : SourceRange(); 256} 257 258//===----------------------------------------------------------------------===// 259// Standard Promotions and Conversions 260//===----------------------------------------------------------------------===// 261 262/// DefaultFunctionArrayConversion (C99 6.3.2.1p3, C99 6.3.2.1p4). 263ExprResult Sema::DefaultFunctionArrayConversion(Expr *E) { 264 QualType Ty = E->getType(); 265 assert(!Ty.isNull() && "DefaultFunctionArrayConversion - missing type"); 266 267 if (Ty->isFunctionType()) 268 E = ImpCastExprToType(E, Context.getPointerType(Ty), 269 CK_FunctionToPointerDecay).take(); 270 else if (Ty->isArrayType()) { 271 // In C90 mode, arrays only promote to pointers if the array expression is 272 // an lvalue. The relevant legalese is C90 6.2.2.1p3: "an lvalue that has 273 // type 'array of type' is converted to an expression that has type 'pointer 274 // to type'...". In C99 this was changed to: C99 6.3.2.1p3: "an expression 275 // that has type 'array of type' ...". The relevant change is "an lvalue" 276 // (C90) to "an expression" (C99). 277 // 278 // C++ 4.2p1: 279 // An lvalue or rvalue of type "array of N T" or "array of unknown bound of 280 // T" can be converted to an rvalue of type "pointer to T". 281 // 282 if (getLangOptions().C99 || getLangOptions().CPlusPlus || E->isLValue()) 283 E = ImpCastExprToType(E, Context.getArrayDecayedType(Ty), 284 CK_ArrayToPointerDecay).take(); 285 } 286 return Owned(E); 287} 288 289static void CheckForNullPointerDereference(Sema &S, Expr *E) { 290 // Check to see if we are dereferencing a null pointer. If so, 291 // and if not volatile-qualified, this is undefined behavior that the 292 // optimizer will delete, so warn about it. People sometimes try to use this 293 // to get a deterministic trap and are surprised by clang's behavior. This 294 // only handles the pattern "*null", which is a very syntactic check. 295 if (UnaryOperator *UO = dyn_cast<UnaryOperator>(E->IgnoreParenCasts())) 296 if (UO->getOpcode() == UO_Deref && 297 UO->getSubExpr()->IgnoreParenCasts()-> 298 isNullPointerConstant(S.Context, Expr::NPC_ValueDependentIsNotNull) && 299 !UO->getType().isVolatileQualified()) { 300 S.DiagRuntimeBehavior(UO->getOperatorLoc(), UO, 301 S.PDiag(diag::warn_indirection_through_null) 302 << UO->getSubExpr()->getSourceRange()); 303 S.DiagRuntimeBehavior(UO->getOperatorLoc(), UO, 304 S.PDiag(diag::note_indirection_through_null)); 305 } 306} 307 308ExprResult Sema::DefaultLvalueConversion(Expr *E) { 309 // C++ [conv.lval]p1: 310 // A glvalue of a non-function, non-array type T can be 311 // converted to a prvalue. 312 if (!E->isGLValue()) return Owned(E); 313 314 QualType T = E->getType(); 315 assert(!T.isNull() && "r-value conversion on typeless expression?"); 316 317 // Create a load out of an ObjCProperty l-value, if necessary. 318 if (E->getObjectKind() == OK_ObjCProperty) { 319 ExprResult Res = ConvertPropertyForRValue(E); 320 if (Res.isInvalid()) 321 return Owned(E); 322 E = Res.take(); 323 if (!E->isGLValue()) 324 return Owned(E); 325 } 326 327 // We don't want to throw lvalue-to-rvalue casts on top of 328 // expressions of certain types in C++. 329 if (getLangOptions().CPlusPlus && 330 (E->getType() == Context.OverloadTy || 331 T->isDependentType() || 332 T->isRecordType())) 333 return Owned(E); 334 335 // The C standard is actually really unclear on this point, and 336 // DR106 tells us what the result should be but not why. It's 337 // generally best to say that void types just doesn't undergo 338 // lvalue-to-rvalue at all. Note that expressions of unqualified 339 // 'void' type are never l-values, but qualified void can be. 340 if (T->isVoidType()) 341 return Owned(E); 342 343 CheckForNullPointerDereference(*this, E); 344 345 // C++ [conv.lval]p1: 346 // [...] If T is a non-class type, the type of the prvalue is the 347 // cv-unqualified version of T. Otherwise, the type of the 348 // rvalue is T. 349 // 350 // C99 6.3.2.1p2: 351 // If the lvalue has qualified type, the value has the unqualified 352 // version of the type of the lvalue; otherwise, the value has the 353 // type of the lvalue. 354 if (T.hasQualifiers()) 355 T = T.getUnqualifiedType(); 356 357 CheckArrayAccess(E); 358 359 return Owned(ImplicitCastExpr::Create(Context, T, CK_LValueToRValue, 360 E, 0, VK_RValue)); 361} 362 363ExprResult Sema::DefaultFunctionArrayLvalueConversion(Expr *E) { 364 ExprResult Res = DefaultFunctionArrayConversion(E); 365 if (Res.isInvalid()) 366 return ExprError(); 367 Res = DefaultLvalueConversion(Res.take()); 368 if (Res.isInvalid()) 369 return ExprError(); 370 return move(Res); 371} 372 373 374/// UsualUnaryConversions - Performs various conversions that are common to most 375/// operators (C99 6.3). The conversions of array and function types are 376/// sometimes suppressed. For example, the array->pointer conversion doesn't 377/// apply if the array is an argument to the sizeof or address (&) operators. 378/// In these instances, this routine should *not* be called. 379ExprResult Sema::UsualUnaryConversions(Expr *E) { 380 // First, convert to an r-value. 381 ExprResult Res = DefaultFunctionArrayLvalueConversion(E); 382 if (Res.isInvalid()) 383 return Owned(E); 384 E = Res.take(); 385 386 QualType Ty = E->getType(); 387 assert(!Ty.isNull() && "UsualUnaryConversions - missing type"); 388 389 // Try to perform integral promotions if the object has a theoretically 390 // promotable type. 391 if (Ty->isIntegralOrUnscopedEnumerationType()) { 392 // C99 6.3.1.1p2: 393 // 394 // The following may be used in an expression wherever an int or 395 // unsigned int may be used: 396 // - an object or expression with an integer type whose integer 397 // conversion rank is less than or equal to the rank of int 398 // and unsigned int. 399 // - A bit-field of type _Bool, int, signed int, or unsigned int. 400 // 401 // If an int can represent all values of the original type, the 402 // value is converted to an int; otherwise, it is converted to an 403 // unsigned int. These are called the integer promotions. All 404 // other types are unchanged by the integer promotions. 405 406 QualType PTy = Context.isPromotableBitField(E); 407 if (!PTy.isNull()) { 408 E = ImpCastExprToType(E, PTy, CK_IntegralCast).take(); 409 return Owned(E); 410 } 411 if (Ty->isPromotableIntegerType()) { 412 QualType PT = Context.getPromotedIntegerType(Ty); 413 E = ImpCastExprToType(E, PT, CK_IntegralCast).take(); 414 return Owned(E); 415 } 416 } 417 return Owned(E); 418} 419 420/// DefaultArgumentPromotion (C99 6.5.2.2p6). Used for function calls that 421/// do not have a prototype. Arguments that have type float are promoted to 422/// double. All other argument types are converted by UsualUnaryConversions(). 423ExprResult Sema::DefaultArgumentPromotion(Expr *E) { 424 QualType Ty = E->getType(); 425 assert(!Ty.isNull() && "DefaultArgumentPromotion - missing type"); 426 427 ExprResult Res = UsualUnaryConversions(E); 428 if (Res.isInvalid()) 429 return Owned(E); 430 E = Res.take(); 431 432 // If this is a 'float' (CVR qualified or typedef) promote to double. 433 if (Ty->isSpecificBuiltinType(BuiltinType::Float)) 434 E = ImpCastExprToType(E, Context.DoubleTy, CK_FloatingCast).take(); 435 436 return Owned(E); 437} 438 439/// DefaultVariadicArgumentPromotion - Like DefaultArgumentPromotion, but 440/// will warn if the resulting type is not a POD type, and rejects ObjC 441/// interfaces passed by value. 442ExprResult Sema::DefaultVariadicArgumentPromotion(Expr *E, VariadicCallType CT, 443 FunctionDecl *FDecl) { 444 ExprResult ExprRes = CheckPlaceholderExpr(E); 445 if (ExprRes.isInvalid()) 446 return ExprError(); 447 448 ExprRes = DefaultArgumentPromotion(E); 449 if (ExprRes.isInvalid()) 450 return ExprError(); 451 E = ExprRes.take(); 452 453 // __builtin_va_start takes the second argument as a "varargs" argument, but 454 // it doesn't actually do anything with it. It doesn't need to be non-pod 455 // etc. 456 if (FDecl && FDecl->getBuiltinID() == Builtin::BI__builtin_va_start) 457 return Owned(E); 458 459 // Don't allow one to pass an Objective-C interface to a vararg. 460 if (E->getType()->isObjCObjectType() && 461 DiagRuntimeBehavior(E->getLocStart(), 0, 462 PDiag(diag::err_cannot_pass_objc_interface_to_vararg) 463 << E->getType() << CT)) 464 return ExprError(); 465 466 if (!E->getType().isPODType(Context)) { 467 // C++0x [expr.call]p7: 468 // Passing a potentially-evaluated argument of class type (Clause 9) 469 // having a non-trivial copy constructor, a non-trivial move constructor, 470 // or a non-trivial destructor, with no corresponding parameter, 471 // is conditionally-supported with implementation-defined semantics. 472 bool TrivialEnough = false; 473 if (getLangOptions().CPlusPlus0x && !E->getType()->isDependentType()) { 474 if (CXXRecordDecl *Record = E->getType()->getAsCXXRecordDecl()) { 475 if (Record->hasTrivialCopyConstructor() && 476 Record->hasTrivialMoveConstructor() && 477 Record->hasTrivialDestructor()) 478 TrivialEnough = true; 479 } 480 } 481 482 if (!TrivialEnough && 483 getLangOptions().ObjCAutoRefCount && 484 E->getType()->isObjCLifetimeType()) 485 TrivialEnough = true; 486 487 if (TrivialEnough) { 488 // Nothing to diagnose. This is okay. 489 } else if (DiagRuntimeBehavior(E->getLocStart(), 0, 490 PDiag(diag::warn_cannot_pass_non_pod_arg_to_vararg) 491 << getLangOptions().CPlusPlus0x << E->getType() 492 << CT)) { 493 // Turn this into a trap. 494 CXXScopeSpec SS; 495 UnqualifiedId Name; 496 Name.setIdentifier(PP.getIdentifierInfo("__builtin_trap"), 497 E->getLocStart()); 498 ExprResult TrapFn = ActOnIdExpression(TUScope, SS, Name, true, false); 499 if (TrapFn.isInvalid()) 500 return ExprError(); 501 502 ExprResult Call = ActOnCallExpr(TUScope, TrapFn.get(), E->getLocStart(), 503 MultiExprArg(), E->getLocEnd()); 504 if (Call.isInvalid()) 505 return ExprError(); 506 507 ExprResult Comma = ActOnBinOp(TUScope, E->getLocStart(), tok::comma, 508 Call.get(), E); 509 if (Comma.isInvalid()) 510 return ExprError(); 511 512 E = Comma.get(); 513 } 514 } 515 516 return Owned(E); 517} 518 519/// UsualArithmeticConversions - Performs various conversions that are common to 520/// binary operators (C99 6.3.1.8). If both operands aren't arithmetic, this 521/// routine returns the first non-arithmetic type found. The client is 522/// responsible for emitting appropriate error diagnostics. 523/// FIXME: verify the conversion rules for "complex int" are consistent with 524/// GCC. 525QualType Sema::UsualArithmeticConversions(ExprResult &lhsExpr, ExprResult &rhsExpr, 526 bool isCompAssign) { 527 if (!isCompAssign) { 528 lhsExpr = UsualUnaryConversions(lhsExpr.take()); 529 if (lhsExpr.isInvalid()) 530 return QualType(); 531 } 532 533 rhsExpr = UsualUnaryConversions(rhsExpr.take()); 534 if (rhsExpr.isInvalid()) 535 return QualType(); 536 537 // For conversion purposes, we ignore any qualifiers. 538 // For example, "const float" and "float" are equivalent. 539 QualType lhs = 540 Context.getCanonicalType(lhsExpr.get()->getType()).getUnqualifiedType(); 541 QualType rhs = 542 Context.getCanonicalType(rhsExpr.get()->getType()).getUnqualifiedType(); 543 544 // If both types are identical, no conversion is needed. 545 if (lhs == rhs) 546 return lhs; 547 548 // If either side is a non-arithmetic type (e.g. a pointer), we are done. 549 // The caller can deal with this (e.g. pointer + int). 550 if (!lhs->isArithmeticType() || !rhs->isArithmeticType()) 551 return lhs; 552 553 // Apply unary and bitfield promotions to the LHS's type. 554 QualType lhs_unpromoted = lhs; 555 if (lhs->isPromotableIntegerType()) 556 lhs = Context.getPromotedIntegerType(lhs); 557 QualType LHSBitfieldPromoteTy = Context.isPromotableBitField(lhsExpr.get()); 558 if (!LHSBitfieldPromoteTy.isNull()) 559 lhs = LHSBitfieldPromoteTy; 560 if (lhs != lhs_unpromoted && !isCompAssign) 561 lhsExpr = ImpCastExprToType(lhsExpr.take(), lhs, CK_IntegralCast); 562 563 // If both types are identical, no conversion is needed. 564 if (lhs == rhs) 565 return lhs; 566 567 // At this point, we have two different arithmetic types. 568 569 // Handle complex types first (C99 6.3.1.8p1). 570 bool LHSComplexFloat = lhs->isComplexType(); 571 bool RHSComplexFloat = rhs->isComplexType(); 572 if (LHSComplexFloat || RHSComplexFloat) { 573 // if we have an integer operand, the result is the complex type. 574 575 if (!RHSComplexFloat && !rhs->isRealFloatingType()) { 576 if (rhs->isIntegerType()) { 577 QualType fp = cast<ComplexType>(lhs)->getElementType(); 578 rhsExpr = ImpCastExprToType(rhsExpr.take(), fp, CK_IntegralToFloating); 579 rhsExpr = ImpCastExprToType(rhsExpr.take(), lhs, CK_FloatingRealToComplex); 580 } else { 581 assert(rhs->isComplexIntegerType()); 582 rhsExpr = ImpCastExprToType(rhsExpr.take(), lhs, CK_IntegralComplexToFloatingComplex); 583 } 584 return lhs; 585 } 586 587 if (!LHSComplexFloat && !lhs->isRealFloatingType()) { 588 if (!isCompAssign) { 589 // int -> float -> _Complex float 590 if (lhs->isIntegerType()) { 591 QualType fp = cast<ComplexType>(rhs)->getElementType(); 592 lhsExpr = ImpCastExprToType(lhsExpr.take(), fp, CK_IntegralToFloating); 593 lhsExpr = ImpCastExprToType(lhsExpr.take(), rhs, CK_FloatingRealToComplex); 594 } else { 595 assert(lhs->isComplexIntegerType()); 596 lhsExpr = ImpCastExprToType(lhsExpr.take(), rhs, CK_IntegralComplexToFloatingComplex); 597 } 598 } 599 return rhs; 600 } 601 602 // This handles complex/complex, complex/float, or float/complex. 603 // When both operands are complex, the shorter operand is converted to the 604 // type of the longer, and that is the type of the result. This corresponds 605 // to what is done when combining two real floating-point operands. 606 // The fun begins when size promotion occur across type domains. 607 // From H&S 6.3.4: When one operand is complex and the other is a real 608 // floating-point type, the less precise type is converted, within it's 609 // real or complex domain, to the precision of the other type. For example, 610 // when combining a "long double" with a "double _Complex", the 611 // "double _Complex" is promoted to "long double _Complex". 612 int order = Context.getFloatingTypeOrder(lhs, rhs); 613 614 // If both are complex, just cast to the more precise type. 615 if (LHSComplexFloat && RHSComplexFloat) { 616 if (order > 0) { 617 // _Complex float -> _Complex double 618 rhsExpr = ImpCastExprToType(rhsExpr.take(), lhs, CK_FloatingComplexCast); 619 return lhs; 620 621 } else if (order < 0) { 622 // _Complex float -> _Complex double 623 if (!isCompAssign) 624 lhsExpr = ImpCastExprToType(lhsExpr.take(), rhs, CK_FloatingComplexCast); 625 return rhs; 626 } 627 return lhs; 628 } 629 630 // If just the LHS is complex, the RHS needs to be converted, 631 // and the LHS might need to be promoted. 632 if (LHSComplexFloat) { 633 if (order > 0) { // LHS is wider 634 // float -> _Complex double 635 QualType fp = cast<ComplexType>(lhs)->getElementType(); 636 rhsExpr = ImpCastExprToType(rhsExpr.take(), fp, CK_FloatingCast); 637 rhsExpr = ImpCastExprToType(rhsExpr.take(), lhs, CK_FloatingRealToComplex); 638 return lhs; 639 } 640 641 // RHS is at least as wide. Find its corresponding complex type. 642 QualType result = (order == 0 ? lhs : Context.getComplexType(rhs)); 643 644 // double -> _Complex double 645 rhsExpr = ImpCastExprToType(rhsExpr.take(), result, CK_FloatingRealToComplex); 646 647 // _Complex float -> _Complex double 648 if (!isCompAssign && order < 0) 649 lhsExpr = ImpCastExprToType(lhsExpr.take(), result, CK_FloatingComplexCast); 650 651 return result; 652 } 653 654 // Just the RHS is complex, so the LHS needs to be converted 655 // and the RHS might need to be promoted. 656 assert(RHSComplexFloat); 657 658 if (order < 0) { // RHS is wider 659 // float -> _Complex double 660 if (!isCompAssign) { 661 QualType fp = cast<ComplexType>(rhs)->getElementType(); 662 lhsExpr = ImpCastExprToType(lhsExpr.take(), fp, CK_FloatingCast); 663 lhsExpr = ImpCastExprToType(lhsExpr.take(), rhs, CK_FloatingRealToComplex); 664 } 665 return rhs; 666 } 667 668 // LHS is at least as wide. Find its corresponding complex type. 669 QualType result = (order == 0 ? rhs : Context.getComplexType(lhs)); 670 671 // double -> _Complex double 672 if (!isCompAssign) 673 lhsExpr = ImpCastExprToType(lhsExpr.take(), result, CK_FloatingRealToComplex); 674 675 // _Complex float -> _Complex double 676 if (order > 0) 677 rhsExpr = ImpCastExprToType(rhsExpr.take(), result, CK_FloatingComplexCast); 678 679 return result; 680 } 681 682 // Now handle "real" floating types (i.e. float, double, long double). 683 bool LHSFloat = lhs->isRealFloatingType(); 684 bool RHSFloat = rhs->isRealFloatingType(); 685 if (LHSFloat || RHSFloat) { 686 // If we have two real floating types, convert the smaller operand 687 // to the bigger result. 688 if (LHSFloat && RHSFloat) { 689 int order = Context.getFloatingTypeOrder(lhs, rhs); 690 if (order > 0) { 691 rhsExpr = ImpCastExprToType(rhsExpr.take(), lhs, CK_FloatingCast); 692 return lhs; 693 } 694 695 assert(order < 0 && "illegal float comparison"); 696 if (!isCompAssign) 697 lhsExpr = ImpCastExprToType(lhsExpr.take(), rhs, CK_FloatingCast); 698 return rhs; 699 } 700 701 // If we have an integer operand, the result is the real floating type. 702 if (LHSFloat) { 703 if (rhs->isIntegerType()) { 704 // Convert rhs to the lhs floating point type. 705 rhsExpr = ImpCastExprToType(rhsExpr.take(), lhs, CK_IntegralToFloating); 706 return lhs; 707 } 708 709 // Convert both sides to the appropriate complex float. 710 assert(rhs->isComplexIntegerType()); 711 QualType result = Context.getComplexType(lhs); 712 713 // _Complex int -> _Complex float 714 rhsExpr = ImpCastExprToType(rhsExpr.take(), result, CK_IntegralComplexToFloatingComplex); 715 716 // float -> _Complex float 717 if (!isCompAssign) 718 lhsExpr = ImpCastExprToType(lhsExpr.take(), result, CK_FloatingRealToComplex); 719 720 return result; 721 } 722 723 assert(RHSFloat); 724 if (lhs->isIntegerType()) { 725 // Convert lhs to the rhs floating point type. 726 if (!isCompAssign) 727 lhsExpr = ImpCastExprToType(lhsExpr.take(), rhs, CK_IntegralToFloating); 728 return rhs; 729 } 730 731 // Convert both sides to the appropriate complex float. 732 assert(lhs->isComplexIntegerType()); 733 QualType result = Context.getComplexType(rhs); 734 735 // _Complex int -> _Complex float 736 if (!isCompAssign) 737 lhsExpr = ImpCastExprToType(lhsExpr.take(), result, CK_IntegralComplexToFloatingComplex); 738 739 // float -> _Complex float 740 rhsExpr = ImpCastExprToType(rhsExpr.take(), result, CK_FloatingRealToComplex); 741 742 return result; 743 } 744 745 // Handle GCC complex int extension. 746 // FIXME: if the operands are (int, _Complex long), we currently 747 // don't promote the complex. Also, signedness? 748 const ComplexType *lhsComplexInt = lhs->getAsComplexIntegerType(); 749 const ComplexType *rhsComplexInt = rhs->getAsComplexIntegerType(); 750 if (lhsComplexInt && rhsComplexInt) { 751 int order = Context.getIntegerTypeOrder(lhsComplexInt->getElementType(), 752 rhsComplexInt->getElementType()); 753 assert(order && "inequal types with equal element ordering"); 754 if (order > 0) { 755 // _Complex int -> _Complex long 756 rhsExpr = ImpCastExprToType(rhsExpr.take(), lhs, CK_IntegralComplexCast); 757 return lhs; 758 } 759 760 if (!isCompAssign) 761 lhsExpr = ImpCastExprToType(lhsExpr.take(), rhs, CK_IntegralComplexCast); 762 return rhs; 763 } else if (lhsComplexInt) { 764 // int -> _Complex int 765 rhsExpr = ImpCastExprToType(rhsExpr.take(), lhs, CK_IntegralRealToComplex); 766 return lhs; 767 } else if (rhsComplexInt) { 768 // int -> _Complex int 769 if (!isCompAssign) 770 lhsExpr = ImpCastExprToType(lhsExpr.take(), rhs, CK_IntegralRealToComplex); 771 return rhs; 772 } 773 774 // Finally, we have two differing integer types. 775 // The rules for this case are in C99 6.3.1.8 776 int compare = Context.getIntegerTypeOrder(lhs, rhs); 777 bool lhsSigned = lhs->hasSignedIntegerRepresentation(), 778 rhsSigned = rhs->hasSignedIntegerRepresentation(); 779 if (lhsSigned == rhsSigned) { 780 // Same signedness; use the higher-ranked type 781 if (compare >= 0) { 782 rhsExpr = ImpCastExprToType(rhsExpr.take(), lhs, CK_IntegralCast); 783 return lhs; 784 } else if (!isCompAssign) 785 lhsExpr = ImpCastExprToType(lhsExpr.take(), rhs, CK_IntegralCast); 786 return rhs; 787 } else if (compare != (lhsSigned ? 1 : -1)) { 788 // The unsigned type has greater than or equal rank to the 789 // signed type, so use the unsigned type 790 if (rhsSigned) { 791 rhsExpr = ImpCastExprToType(rhsExpr.take(), lhs, CK_IntegralCast); 792 return lhs; 793 } else if (!isCompAssign) 794 lhsExpr = ImpCastExprToType(lhsExpr.take(), rhs, CK_IntegralCast); 795 return rhs; 796 } else if (Context.getIntWidth(lhs) != Context.getIntWidth(rhs)) { 797 // The two types are different widths; if we are here, that 798 // means the signed type is larger than the unsigned type, so 799 // use the signed type. 800 if (lhsSigned) { 801 rhsExpr = ImpCastExprToType(rhsExpr.take(), lhs, CK_IntegralCast); 802 return lhs; 803 } else if (!isCompAssign) 804 lhsExpr = ImpCastExprToType(lhsExpr.take(), rhs, CK_IntegralCast); 805 return rhs; 806 } else { 807 // The signed type is higher-ranked than the unsigned type, 808 // but isn't actually any bigger (like unsigned int and long 809 // on most 32-bit systems). Use the unsigned type corresponding 810 // to the signed type. 811 QualType result = 812 Context.getCorrespondingUnsignedType(lhsSigned ? lhs : rhs); 813 rhsExpr = ImpCastExprToType(rhsExpr.take(), result, CK_IntegralCast); 814 if (!isCompAssign) 815 lhsExpr = ImpCastExprToType(lhsExpr.take(), result, CK_IntegralCast); 816 return result; 817 } 818} 819 820//===----------------------------------------------------------------------===// 821// Semantic Analysis for various Expression Types 822//===----------------------------------------------------------------------===// 823 824 825ExprResult 826Sema::ActOnGenericSelectionExpr(SourceLocation KeyLoc, 827 SourceLocation DefaultLoc, 828 SourceLocation RParenLoc, 829 Expr *ControllingExpr, 830 MultiTypeArg types, 831 MultiExprArg exprs) { 832 unsigned NumAssocs = types.size(); 833 assert(NumAssocs == exprs.size()); 834 835 ParsedType *ParsedTypes = types.release(); 836 Expr **Exprs = exprs.release(); 837 838 TypeSourceInfo **Types = new TypeSourceInfo*[NumAssocs]; 839 for (unsigned i = 0; i < NumAssocs; ++i) { 840 if (ParsedTypes[i]) 841 (void) GetTypeFromParser(ParsedTypes[i], &Types[i]); 842 else 843 Types[i] = 0; 844 } 845 846 ExprResult ER = CreateGenericSelectionExpr(KeyLoc, DefaultLoc, RParenLoc, 847 ControllingExpr, Types, Exprs, 848 NumAssocs); 849 delete [] Types; 850 return ER; 851} 852 853ExprResult 854Sema::CreateGenericSelectionExpr(SourceLocation KeyLoc, 855 SourceLocation DefaultLoc, 856 SourceLocation RParenLoc, 857 Expr *ControllingExpr, 858 TypeSourceInfo **Types, 859 Expr **Exprs, 860 unsigned NumAssocs) { 861 bool TypeErrorFound = false, 862 IsResultDependent = ControllingExpr->isTypeDependent(), 863 ContainsUnexpandedParameterPack 864 = ControllingExpr->containsUnexpandedParameterPack(); 865 866 for (unsigned i = 0; i < NumAssocs; ++i) { 867 if (Exprs[i]->containsUnexpandedParameterPack()) 868 ContainsUnexpandedParameterPack = true; 869 870 if (Types[i]) { 871 if (Types[i]->getType()->containsUnexpandedParameterPack()) 872 ContainsUnexpandedParameterPack = true; 873 874 if (Types[i]->getType()->isDependentType()) { 875 IsResultDependent = true; 876 } else { 877 // C1X 6.5.1.1p2 "The type name in a generic association shall specify a 878 // complete object type other than a variably modified type." 879 unsigned D = 0; 880 if (Types[i]->getType()->isIncompleteType()) 881 D = diag::err_assoc_type_incomplete; 882 else if (!Types[i]->getType()->isObjectType()) 883 D = diag::err_assoc_type_nonobject; 884 else if (Types[i]->getType()->isVariablyModifiedType()) 885 D = diag::err_assoc_type_variably_modified; 886 887 if (D != 0) { 888 Diag(Types[i]->getTypeLoc().getBeginLoc(), D) 889 << Types[i]->getTypeLoc().getSourceRange() 890 << Types[i]->getType(); 891 TypeErrorFound = true; 892 } 893 894 // C1X 6.5.1.1p2 "No two generic associations in the same generic 895 // selection shall specify compatible types." 896 for (unsigned j = i+1; j < NumAssocs; ++j) 897 if (Types[j] && !Types[j]->getType()->isDependentType() && 898 Context.typesAreCompatible(Types[i]->getType(), 899 Types[j]->getType())) { 900 Diag(Types[j]->getTypeLoc().getBeginLoc(), 901 diag::err_assoc_compatible_types) 902 << Types[j]->getTypeLoc().getSourceRange() 903 << Types[j]->getType() 904 << Types[i]->getType(); 905 Diag(Types[i]->getTypeLoc().getBeginLoc(), 906 diag::note_compat_assoc) 907 << Types[i]->getTypeLoc().getSourceRange() 908 << Types[i]->getType(); 909 TypeErrorFound = true; 910 } 911 } 912 } 913 } 914 if (TypeErrorFound) 915 return ExprError(); 916 917 // If we determined that the generic selection is result-dependent, don't 918 // try to compute the result expression. 919 if (IsResultDependent) 920 return Owned(new (Context) GenericSelectionExpr( 921 Context, KeyLoc, ControllingExpr, 922 Types, Exprs, NumAssocs, DefaultLoc, 923 RParenLoc, ContainsUnexpandedParameterPack)); 924 925 llvm::SmallVector<unsigned, 1> CompatIndices; 926 unsigned DefaultIndex = -1U; 927 for (unsigned i = 0; i < NumAssocs; ++i) { 928 if (!Types[i]) 929 DefaultIndex = i; 930 else if (Context.typesAreCompatible(ControllingExpr->getType(), 931 Types[i]->getType())) 932 CompatIndices.push_back(i); 933 } 934 935 // C1X 6.5.1.1p2 "The controlling expression of a generic selection shall have 936 // type compatible with at most one of the types named in its generic 937 // association list." 938 if (CompatIndices.size() > 1) { 939 // We strip parens here because the controlling expression is typically 940 // parenthesized in macro definitions. 941 ControllingExpr = ControllingExpr->IgnoreParens(); 942 Diag(ControllingExpr->getLocStart(), diag::err_generic_sel_multi_match) 943 << ControllingExpr->getSourceRange() << ControllingExpr->getType() 944 << (unsigned) CompatIndices.size(); 945 for (llvm::SmallVector<unsigned, 1>::iterator I = CompatIndices.begin(), 946 E = CompatIndices.end(); I != E; ++I) { 947 Diag(Types[*I]->getTypeLoc().getBeginLoc(), 948 diag::note_compat_assoc) 949 << Types[*I]->getTypeLoc().getSourceRange() 950 << Types[*I]->getType(); 951 } 952 return ExprError(); 953 } 954 955 // C1X 6.5.1.1p2 "If a generic selection has no default generic association, 956 // its controlling expression shall have type compatible with exactly one of 957 // the types named in its generic association list." 958 if (DefaultIndex == -1U && CompatIndices.size() == 0) { 959 // We strip parens here because the controlling expression is typically 960 // parenthesized in macro definitions. 961 ControllingExpr = ControllingExpr->IgnoreParens(); 962 Diag(ControllingExpr->getLocStart(), diag::err_generic_sel_no_match) 963 << ControllingExpr->getSourceRange() << ControllingExpr->getType(); 964 return ExprError(); 965 } 966 967 // C1X 6.5.1.1p3 "If a generic selection has a generic association with a 968 // type name that is compatible with the type of the controlling expression, 969 // then the result expression of the generic selection is the expression 970 // in that generic association. Otherwise, the result expression of the 971 // generic selection is the expression in the default generic association." 972 unsigned ResultIndex = 973 CompatIndices.size() ? CompatIndices[0] : DefaultIndex; 974 975 return Owned(new (Context) GenericSelectionExpr( 976 Context, KeyLoc, ControllingExpr, 977 Types, Exprs, NumAssocs, DefaultLoc, 978 RParenLoc, ContainsUnexpandedParameterPack, 979 ResultIndex)); 980} 981 982/// ActOnStringLiteral - The specified tokens were lexed as pasted string 983/// fragments (e.g. "foo" "bar" L"baz"). The result string has to handle string 984/// concatenation ([C99 5.1.1.2, translation phase #6]), so it may come from 985/// multiple tokens. However, the common case is that StringToks points to one 986/// string. 987/// 988ExprResult 989Sema::ActOnStringLiteral(const Token *StringToks, unsigned NumStringToks) { 990 assert(NumStringToks && "Must have at least one string!"); 991 992 StringLiteralParser Literal(StringToks, NumStringToks, PP); 993 if (Literal.hadError) 994 return ExprError(); 995 996 llvm::SmallVector<SourceLocation, 4> StringTokLocs; 997 for (unsigned i = 0; i != NumStringToks; ++i) 998 StringTokLocs.push_back(StringToks[i].getLocation()); 999 1000 QualType StrTy = Context.CharTy; 1001 if (Literal.AnyWide) 1002 StrTy = Context.getWCharType(); 1003 else if (Literal.Pascal) 1004 StrTy = Context.UnsignedCharTy; 1005 1006 // A C++ string literal has a const-qualified element type (C++ 2.13.4p1). 1007 if (getLangOptions().CPlusPlus || getLangOptions().ConstStrings) 1008 StrTy.addConst(); 1009 1010 // Get an array type for the string, according to C99 6.4.5. This includes 1011 // the nul terminator character as well as the string length for pascal 1012 // strings. 1013 StrTy = Context.getConstantArrayType(StrTy, 1014 llvm::APInt(32, Literal.GetNumStringChars()+1), 1015 ArrayType::Normal, 0); 1016 1017 // Pass &StringTokLocs[0], StringTokLocs.size() to factory! 1018 return Owned(StringLiteral::Create(Context, Literal.GetString(), 1019 Literal.AnyWide, Literal.Pascal, StrTy, 1020 &StringTokLocs[0], 1021 StringTokLocs.size())); 1022} 1023 1024enum CaptureResult { 1025 /// No capture is required. 1026 CR_NoCapture, 1027 1028 /// A capture is required. 1029 CR_Capture, 1030 1031 /// A by-ref capture is required. 1032 CR_CaptureByRef, 1033 1034 /// An error occurred when trying to capture the given variable. 1035 CR_Error 1036}; 1037 1038/// Diagnose an uncapturable value reference. 1039/// 1040/// \param var - the variable referenced 1041/// \param DC - the context which we couldn't capture through 1042static CaptureResult 1043diagnoseUncapturableValueReference(Sema &S, SourceLocation loc, 1044 VarDecl *var, DeclContext *DC) { 1045 switch (S.ExprEvalContexts.back().Context) { 1046 case Sema::Unevaluated: 1047 // The argument will never be evaluated, so don't complain. 1048 return CR_NoCapture; 1049 1050 case Sema::PotentiallyEvaluated: 1051 case Sema::PotentiallyEvaluatedIfUsed: 1052 break; 1053 1054 case Sema::PotentiallyPotentiallyEvaluated: 1055 // FIXME: delay these! 1056 break; 1057 } 1058 1059 // Don't diagnose about capture if we're not actually in code right 1060 // now; in general, there are more appropriate places that will 1061 // diagnose this. 1062 if (!S.CurContext->isFunctionOrMethod()) return CR_NoCapture; 1063 1064 // Certain madnesses can happen with parameter declarations, which 1065 // we want to ignore. 1066 if (isa<ParmVarDecl>(var)) { 1067 // - If the parameter still belongs to the translation unit, then 1068 // we're actually just using one parameter in the declaration of 1069 // the next. This is useful in e.g. VLAs. 1070 if (isa<TranslationUnitDecl>(var->getDeclContext())) 1071 return CR_NoCapture; 1072 1073 // - This particular madness can happen in ill-formed default 1074 // arguments; claim it's okay and let downstream code handle it. 1075 if (S.CurContext == var->getDeclContext()->getParent()) 1076 return CR_NoCapture; 1077 } 1078 1079 DeclarationName functionName; 1080 if (FunctionDecl *fn = dyn_cast<FunctionDecl>(var->getDeclContext())) 1081 functionName = fn->getDeclName(); 1082 // FIXME: variable from enclosing block that we couldn't capture from! 1083 1084 S.Diag(loc, diag::err_reference_to_local_var_in_enclosing_function) 1085 << var->getIdentifier() << functionName; 1086 S.Diag(var->getLocation(), diag::note_local_variable_declared_here) 1087 << var->getIdentifier(); 1088 1089 return CR_Error; 1090} 1091 1092/// There is a well-formed capture at a particular scope level; 1093/// propagate it through all the nested blocks. 1094static CaptureResult propagateCapture(Sema &S, unsigned validScopeIndex, 1095 const BlockDecl::Capture &capture) { 1096 VarDecl *var = capture.getVariable(); 1097 1098 // Update all the inner blocks with the capture information. 1099 for (unsigned i = validScopeIndex + 1, e = S.FunctionScopes.size(); 1100 i != e; ++i) { 1101 BlockScopeInfo *innerBlock = cast<BlockScopeInfo>(S.FunctionScopes[i]); 1102 innerBlock->Captures.push_back( 1103 BlockDecl::Capture(capture.getVariable(), capture.isByRef(), 1104 /*nested*/ true, capture.getCopyExpr())); 1105 innerBlock->CaptureMap[var] = innerBlock->Captures.size(); // +1 1106 } 1107 1108 return capture.isByRef() ? CR_CaptureByRef : CR_Capture; 1109} 1110 1111/// shouldCaptureValueReference - Determine if a reference to the 1112/// given value in the current context requires a variable capture. 1113/// 1114/// This also keeps the captures set in the BlockScopeInfo records 1115/// up-to-date. 1116static CaptureResult shouldCaptureValueReference(Sema &S, SourceLocation loc, 1117 ValueDecl *value) { 1118 // Only variables ever require capture. 1119 VarDecl *var = dyn_cast<VarDecl>(value); 1120 if (!var) return CR_NoCapture; 1121 1122 // Fast path: variables from the current context never require capture. 1123 DeclContext *DC = S.CurContext; 1124 if (var->getDeclContext() == DC) return CR_NoCapture; 1125 1126 // Only variables with local storage require capture. 1127 // FIXME: What about 'const' variables in C++? 1128 if (!var->hasLocalStorage()) return CR_NoCapture; 1129 1130 // Otherwise, we need to capture. 1131 1132 unsigned functionScopesIndex = S.FunctionScopes.size() - 1; 1133 do { 1134 // Only blocks (and eventually C++0x closures) can capture; other 1135 // scopes don't work. 1136 if (!isa<BlockDecl>(DC)) 1137 return diagnoseUncapturableValueReference(S, loc, var, DC); 1138 1139 BlockScopeInfo *blockScope = 1140 cast<BlockScopeInfo>(S.FunctionScopes[functionScopesIndex]); 1141 assert(blockScope->TheDecl == static_cast<BlockDecl*>(DC)); 1142 1143 // Check whether we've already captured it in this block. If so, 1144 // we're done. 1145 if (unsigned indexPlus1 = blockScope->CaptureMap[var]) 1146 return propagateCapture(S, functionScopesIndex, 1147 blockScope->Captures[indexPlus1 - 1]); 1148 1149 functionScopesIndex--; 1150 DC = cast<BlockDecl>(DC)->getDeclContext(); 1151 } while (var->getDeclContext() != DC); 1152 1153 // Okay, we descended all the way to the block that defines the variable. 1154 // Actually try to capture it. 1155 QualType type = var->getType(); 1156 1157 // Prohibit variably-modified types. 1158 if (type->isVariablyModifiedType()) { 1159 S.Diag(loc, diag::err_ref_vm_type); 1160 S.Diag(var->getLocation(), diag::note_declared_at); 1161 return CR_Error; 1162 } 1163 1164 // Prohibit arrays, even in __block variables, but not references to 1165 // them. 1166 if (type->isArrayType()) { 1167 S.Diag(loc, diag::err_ref_array_type); 1168 S.Diag(var->getLocation(), diag::note_declared_at); 1169 return CR_Error; 1170 } 1171 1172 S.MarkDeclarationReferenced(loc, var); 1173 1174 // The BlocksAttr indicates the variable is bound by-reference. 1175 bool byRef = var->hasAttr<BlocksAttr>(); 1176 1177 // Build a copy expression. 1178 Expr *copyExpr = 0; 1179 const RecordType *rtype; 1180 if (!byRef && S.getLangOptions().CPlusPlus && !type->isDependentType() && 1181 (rtype = type->getAs<RecordType>())) { 1182 1183 // The capture logic needs the destructor, so make sure we mark it. 1184 // Usually this is unnecessary because most local variables have 1185 // their destructors marked at declaration time, but parameters are 1186 // an exception because it's technically only the call site that 1187 // actually requires the destructor. 1188 if (isa<ParmVarDecl>(var)) 1189 S.FinalizeVarWithDestructor(var, rtype); 1190 1191 // According to the blocks spec, the capture of a variable from 1192 // the stack requires a const copy constructor. This is not true 1193 // of the copy/move done to move a __block variable to the heap. 1194 type.addConst(); 1195 1196 Expr *declRef = new (S.Context) DeclRefExpr(var, type, VK_LValue, loc); 1197 ExprResult result = 1198 S.PerformCopyInitialization( 1199 InitializedEntity::InitializeBlock(var->getLocation(), 1200 type, false), 1201 loc, S.Owned(declRef)); 1202 1203 // Build a full-expression copy expression if initialization 1204 // succeeded and used a non-trivial constructor. Recover from 1205 // errors by pretending that the copy isn't necessary. 1206 if (!result.isInvalid() && 1207 !cast<CXXConstructExpr>(result.get())->getConstructor()->isTrivial()) { 1208 result = S.MaybeCreateExprWithCleanups(result); 1209 copyExpr = result.take(); 1210 } 1211 } 1212 1213 // We're currently at the declarer; go back to the closure. 1214 functionScopesIndex++; 1215 BlockScopeInfo *blockScope = 1216 cast<BlockScopeInfo>(S.FunctionScopes[functionScopesIndex]); 1217 1218 // Build a valid capture in this scope. 1219 blockScope->Captures.push_back( 1220 BlockDecl::Capture(var, byRef, /*nested*/ false, copyExpr)); 1221 blockScope->CaptureMap[var] = blockScope->Captures.size(); // +1 1222 1223 // Propagate that to inner captures if necessary. 1224 return propagateCapture(S, functionScopesIndex, 1225 blockScope->Captures.back()); 1226} 1227 1228static ExprResult BuildBlockDeclRefExpr(Sema &S, ValueDecl *vd, 1229 const DeclarationNameInfo &NameInfo, 1230 bool byRef) { 1231 assert(isa<VarDecl>(vd) && "capturing non-variable"); 1232 1233 VarDecl *var = cast<VarDecl>(vd); 1234 assert(var->hasLocalStorage() && "capturing non-local"); 1235 assert(byRef == var->hasAttr<BlocksAttr>() && "byref set wrong"); 1236 1237 QualType exprType = var->getType().getNonReferenceType(); 1238 1239 BlockDeclRefExpr *BDRE; 1240 if (!byRef) { 1241 // The variable will be bound by copy; make it const within the 1242 // closure, but record that this was done in the expression. 1243 bool constAdded = !exprType.isConstQualified(); 1244 exprType.addConst(); 1245 1246 BDRE = new (S.Context) BlockDeclRefExpr(var, exprType, VK_LValue, 1247 NameInfo.getLoc(), false, 1248 constAdded); 1249 } else { 1250 BDRE = new (S.Context) BlockDeclRefExpr(var, exprType, VK_LValue, 1251 NameInfo.getLoc(), true); 1252 } 1253 1254 return S.Owned(BDRE); 1255} 1256 1257ExprResult 1258Sema::BuildDeclRefExpr(ValueDecl *D, QualType Ty, ExprValueKind VK, 1259 SourceLocation Loc, 1260 const CXXScopeSpec *SS) { 1261 DeclarationNameInfo NameInfo(D->getDeclName(), Loc); 1262 return BuildDeclRefExpr(D, Ty, VK, NameInfo, SS); 1263} 1264 1265/// BuildDeclRefExpr - Build an expression that references a 1266/// declaration that does not require a closure capture. 1267ExprResult 1268Sema::BuildDeclRefExpr(ValueDecl *D, QualType Ty, ExprValueKind VK, 1269 const DeclarationNameInfo &NameInfo, 1270 const CXXScopeSpec *SS) { 1271 MarkDeclarationReferenced(NameInfo.getLoc(), D); 1272 1273 Expr *E = DeclRefExpr::Create(Context, 1274 SS? SS->getWithLocInContext(Context) 1275 : NestedNameSpecifierLoc(), 1276 D, NameInfo, Ty, VK); 1277 1278 // Just in case we're building an illegal pointer-to-member. 1279 if (isa<FieldDecl>(D) && cast<FieldDecl>(D)->getBitWidth()) 1280 E->setObjectKind(OK_BitField); 1281 1282 return Owned(E); 1283} 1284 1285/// Decomposes the given name into a DeclarationNameInfo, its location, and 1286/// possibly a list of template arguments. 1287/// 1288/// If this produces template arguments, it is permitted to call 1289/// DecomposeTemplateName. 1290/// 1291/// This actually loses a lot of source location information for 1292/// non-standard name kinds; we should consider preserving that in 1293/// some way. 1294void Sema::DecomposeUnqualifiedId(const UnqualifiedId &Id, 1295 TemplateArgumentListInfo &Buffer, 1296 DeclarationNameInfo &NameInfo, 1297 const TemplateArgumentListInfo *&TemplateArgs) { 1298 if (Id.getKind() == UnqualifiedId::IK_TemplateId) { 1299 Buffer.setLAngleLoc(Id.TemplateId->LAngleLoc); 1300 Buffer.setRAngleLoc(Id.TemplateId->RAngleLoc); 1301 1302 ASTTemplateArgsPtr TemplateArgsPtr(*this, 1303 Id.TemplateId->getTemplateArgs(), 1304 Id.TemplateId->NumArgs); 1305 translateTemplateArguments(TemplateArgsPtr, Buffer); 1306 TemplateArgsPtr.release(); 1307 1308 TemplateName TName = Id.TemplateId->Template.get(); 1309 SourceLocation TNameLoc = Id.TemplateId->TemplateNameLoc; 1310 NameInfo = Context.getNameForTemplate(TName, TNameLoc); 1311 TemplateArgs = &Buffer; 1312 } else { 1313 NameInfo = GetNameFromUnqualifiedId(Id); 1314 TemplateArgs = 0; 1315 } 1316} 1317 1318/// Diagnose an empty lookup. 1319/// 1320/// \return false if new lookup candidates were found 1321bool Sema::DiagnoseEmptyLookup(Scope *S, CXXScopeSpec &SS, LookupResult &R, 1322 CorrectTypoContext CTC) { 1323 DeclarationName Name = R.getLookupName(); 1324 1325 unsigned diagnostic = diag::err_undeclared_var_use; 1326 unsigned diagnostic_suggest = diag::err_undeclared_var_use_suggest; 1327 if (Name.getNameKind() == DeclarationName::CXXOperatorName || 1328 Name.getNameKind() == DeclarationName::CXXLiteralOperatorName || 1329 Name.getNameKind() == DeclarationName::CXXConversionFunctionName) { 1330 diagnostic = diag::err_undeclared_use; 1331 diagnostic_suggest = diag::err_undeclared_use_suggest; 1332 } 1333 1334 // If the original lookup was an unqualified lookup, fake an 1335 // unqualified lookup. This is useful when (for example) the 1336 // original lookup would not have found something because it was a 1337 // dependent name. 1338 for (DeclContext *DC = SS.isEmpty() ? CurContext : 0; 1339 DC; DC = DC->getParent()) { 1340 if (isa<CXXRecordDecl>(DC)) { 1341 LookupQualifiedName(R, DC); 1342 1343 if (!R.empty()) { 1344 // Don't give errors about ambiguities in this lookup. 1345 R.suppressDiagnostics(); 1346 1347 CXXMethodDecl *CurMethod = dyn_cast<CXXMethodDecl>(CurContext); 1348 bool isInstance = CurMethod && 1349 CurMethod->isInstance() && 1350 DC == CurMethod->getParent(); 1351 1352 // Give a code modification hint to insert 'this->'. 1353 // TODO: fixit for inserting 'Base<T>::' in the other cases. 1354 // Actually quite difficult! 1355 if (isInstance) { 1356 UnresolvedLookupExpr *ULE = cast<UnresolvedLookupExpr>( 1357 CallsUndergoingInstantiation.back()->getCallee()); 1358 CXXMethodDecl *DepMethod = cast_or_null<CXXMethodDecl>( 1359 CurMethod->getInstantiatedFromMemberFunction()); 1360 if (DepMethod) { 1361 Diag(R.getNameLoc(), diagnostic) << Name 1362 << FixItHint::CreateInsertion(R.getNameLoc(), "this->"); 1363 QualType DepThisType = DepMethod->getThisType(Context); 1364 CXXThisExpr *DepThis = new (Context) CXXThisExpr( 1365 R.getNameLoc(), DepThisType, false); 1366 TemplateArgumentListInfo TList; 1367 if (ULE->hasExplicitTemplateArgs()) 1368 ULE->copyTemplateArgumentsInto(TList); 1369 1370 CXXScopeSpec SS; 1371 SS.Adopt(ULE->getQualifierLoc()); 1372 CXXDependentScopeMemberExpr *DepExpr = 1373 CXXDependentScopeMemberExpr::Create( 1374 Context, DepThis, DepThisType, true, SourceLocation(), 1375 SS.getWithLocInContext(Context), NULL, 1376 R.getLookupNameInfo(), &TList); 1377 CallsUndergoingInstantiation.back()->setCallee(DepExpr); 1378 } else { 1379 // FIXME: we should be able to handle this case too. It is correct 1380 // to add this-> here. This is a workaround for PR7947. 1381 Diag(R.getNameLoc(), diagnostic) << Name; 1382 } 1383 } else { 1384 Diag(R.getNameLoc(), diagnostic) << Name; 1385 } 1386 1387 // Do we really want to note all of these? 1388 for (LookupResult::iterator I = R.begin(), E = R.end(); I != E; ++I) 1389 Diag((*I)->getLocation(), diag::note_dependent_var_use); 1390 1391 // Tell the callee to try to recover. 1392 return false; 1393 } 1394 1395 R.clear(); 1396 } 1397 } 1398 1399 // We didn't find anything, so try to correct for a typo. 1400 TypoCorrection Corrected; 1401 if (S && (Corrected = CorrectTypo(R.getLookupNameInfo(), R.getLookupKind(), 1402 S, &SS, NULL, false, CTC))) { 1403 std::string CorrectedStr(Corrected.getAsString(getLangOptions())); 1404 std::string CorrectedQuotedStr(Corrected.getQuoted(getLangOptions())); 1405 R.setLookupName(Corrected.getCorrection()); 1406 1407 if (NamedDecl *ND = Corrected.getCorrectionDecl()) { 1408 R.addDecl(ND); 1409 if (isa<ValueDecl>(ND) || isa<FunctionTemplateDecl>(ND)) { 1410 if (SS.isEmpty()) 1411 Diag(R.getNameLoc(), diagnostic_suggest) << Name << CorrectedQuotedStr 1412 << FixItHint::CreateReplacement(R.getNameLoc(), CorrectedStr); 1413 else 1414 Diag(R.getNameLoc(), diag::err_no_member_suggest) 1415 << Name << computeDeclContext(SS, false) << CorrectedQuotedStr 1416 << SS.getRange() 1417 << FixItHint::CreateReplacement(R.getNameLoc(), CorrectedStr); 1418 if (ND) 1419 Diag(ND->getLocation(), diag::note_previous_decl) 1420 << CorrectedQuotedStr; 1421 1422 // Tell the callee to try to recover. 1423 return false; 1424 } 1425 1426 if (isa<TypeDecl>(ND) || isa<ObjCInterfaceDecl>(ND)) { 1427 // FIXME: If we ended up with a typo for a type name or 1428 // Objective-C class name, we're in trouble because the parser 1429 // is in the wrong place to recover. Suggest the typo 1430 // correction, but don't make it a fix-it since we're not going 1431 // to recover well anyway. 1432 if (SS.isEmpty()) 1433 Diag(R.getNameLoc(), diagnostic_suggest) << Name << CorrectedQuotedStr; 1434 else 1435 Diag(R.getNameLoc(), diag::err_no_member_suggest) 1436 << Name << computeDeclContext(SS, false) << CorrectedQuotedStr 1437 << SS.getRange(); 1438 1439 // Don't try to recover; it won't work. 1440 return true; 1441 } 1442 } else { 1443 // FIXME: We found a keyword. Suggest it, but don't provide a fix-it 1444 // because we aren't able to recover. 1445 if (SS.isEmpty()) 1446 Diag(R.getNameLoc(), diagnostic_suggest) << Name << CorrectedQuotedStr; 1447 else 1448 Diag(R.getNameLoc(), diag::err_no_member_suggest) 1449 << Name << computeDeclContext(SS, false) << CorrectedQuotedStr 1450 << SS.getRange(); 1451 return true; 1452 } 1453 } 1454 R.clear(); 1455 1456 // Emit a special diagnostic for failed member lookups. 1457 // FIXME: computing the declaration context might fail here (?) 1458 if (!SS.isEmpty()) { 1459 Diag(R.getNameLoc(), diag::err_no_member) 1460 << Name << computeDeclContext(SS, false) 1461 << SS.getRange(); 1462 return true; 1463 } 1464 1465 // Give up, we can't recover. 1466 Diag(R.getNameLoc(), diagnostic) << Name; 1467 return true; 1468} 1469 1470ObjCPropertyDecl *Sema::canSynthesizeProvisionalIvar(IdentifierInfo *II) { 1471 ObjCMethodDecl *CurMeth = getCurMethodDecl(); 1472 ObjCInterfaceDecl *IDecl = CurMeth->getClassInterface(); 1473 if (!IDecl) 1474 return 0; 1475 ObjCImplementationDecl *ClassImpDecl = IDecl->getImplementation(); 1476 if (!ClassImpDecl) 1477 return 0; 1478 ObjCPropertyDecl *property = LookupPropertyDecl(IDecl, II); 1479 if (!property) 1480 return 0; 1481 if (ObjCPropertyImplDecl *PIDecl = ClassImpDecl->FindPropertyImplDecl(II)) 1482 if (PIDecl->getPropertyImplementation() == ObjCPropertyImplDecl::Dynamic || 1483 PIDecl->getPropertyIvarDecl()) 1484 return 0; 1485 return property; 1486} 1487 1488bool Sema::canSynthesizeProvisionalIvar(ObjCPropertyDecl *Property) { 1489 ObjCMethodDecl *CurMeth = getCurMethodDecl(); 1490 ObjCInterfaceDecl *IDecl = CurMeth->getClassInterface(); 1491 if (!IDecl) 1492 return false; 1493 ObjCImplementationDecl *ClassImpDecl = IDecl->getImplementation(); 1494 if (!ClassImpDecl) 1495 return false; 1496 if (ObjCPropertyImplDecl *PIDecl 1497 = ClassImpDecl->FindPropertyImplDecl(Property->getIdentifier())) 1498 if (PIDecl->getPropertyImplementation() == ObjCPropertyImplDecl::Dynamic || 1499 PIDecl->getPropertyIvarDecl()) 1500 return false; 1501 1502 return true; 1503} 1504 1505ObjCIvarDecl *Sema::SynthesizeProvisionalIvar(LookupResult &Lookup, 1506 IdentifierInfo *II, 1507 SourceLocation NameLoc) { 1508 ObjCMethodDecl *CurMeth = getCurMethodDecl(); 1509 bool LookForIvars; 1510 if (Lookup.empty()) 1511 LookForIvars = true; 1512 else if (CurMeth->isClassMethod()) 1513 LookForIvars = false; 1514 else 1515 LookForIvars = (Lookup.isSingleResult() && 1516 Lookup.getFoundDecl()->isDefinedOutsideFunctionOrMethod() && 1517 (Lookup.getAsSingle<VarDecl>() != 0)); 1518 if (!LookForIvars) 1519 return 0; 1520 1521 ObjCInterfaceDecl *IDecl = CurMeth->getClassInterface(); 1522 if (!IDecl) 1523 return 0; 1524 ObjCImplementationDecl *ClassImpDecl = IDecl->getImplementation(); 1525 if (!ClassImpDecl) 1526 return 0; 1527 bool DynamicImplSeen = false; 1528 ObjCPropertyDecl *property = LookupPropertyDecl(IDecl, II); 1529 if (!property) 1530 return 0; 1531 if (ObjCPropertyImplDecl *PIDecl = ClassImpDecl->FindPropertyImplDecl(II)) { 1532 DynamicImplSeen = 1533 (PIDecl->getPropertyImplementation() == ObjCPropertyImplDecl::Dynamic); 1534 // property implementation has a designated ivar. No need to assume a new 1535 // one. 1536 if (!DynamicImplSeen && PIDecl->getPropertyIvarDecl()) 1537 return 0; 1538 } 1539 if (!DynamicImplSeen) { 1540 QualType PropType = Context.getCanonicalType(property->getType()); 1541 ObjCIvarDecl *Ivar = ObjCIvarDecl::Create(Context, ClassImpDecl, 1542 NameLoc, NameLoc, 1543 II, PropType, /*Dinfo=*/0, 1544 ObjCIvarDecl::Private, 1545 (Expr *)0, true); 1546 ClassImpDecl->addDecl(Ivar); 1547 IDecl->makeDeclVisibleInContext(Ivar, false); 1548 property->setPropertyIvarDecl(Ivar); 1549 return Ivar; 1550 } 1551 return 0; 1552} 1553 1554ExprResult Sema::ActOnIdExpression(Scope *S, 1555 CXXScopeSpec &SS, 1556 UnqualifiedId &Id, 1557 bool HasTrailingLParen, 1558 bool isAddressOfOperand) { 1559 assert(!(isAddressOfOperand && HasTrailingLParen) && 1560 "cannot be direct & operand and have a trailing lparen"); 1561 1562 if (SS.isInvalid()) 1563 return ExprError(); 1564 1565 TemplateArgumentListInfo TemplateArgsBuffer; 1566 1567 // Decompose the UnqualifiedId into the following data. 1568 DeclarationNameInfo NameInfo; 1569 const TemplateArgumentListInfo *TemplateArgs; 1570 DecomposeUnqualifiedId(Id, TemplateArgsBuffer, NameInfo, TemplateArgs); 1571 1572 DeclarationName Name = NameInfo.getName(); 1573 IdentifierInfo *II = Name.getAsIdentifierInfo(); 1574 SourceLocation NameLoc = NameInfo.getLoc(); 1575 1576 // C++ [temp.dep.expr]p3: 1577 // An id-expression is type-dependent if it contains: 1578 // -- an identifier that was declared with a dependent type, 1579 // (note: handled after lookup) 1580 // -- a template-id that is dependent, 1581 // (note: handled in BuildTemplateIdExpr) 1582 // -- a conversion-function-id that specifies a dependent type, 1583 // -- a nested-name-specifier that contains a class-name that 1584 // names a dependent type. 1585 // Determine whether this is a member of an unknown specialization; 1586 // we need to handle these differently. 1587 bool DependentID = false; 1588 if (Name.getNameKind() == DeclarationName::CXXConversionFunctionName && 1589 Name.getCXXNameType()->isDependentType()) { 1590 DependentID = true; 1591 } else if (SS.isSet()) { 1592 if (DeclContext *DC = computeDeclContext(SS, false)) { 1593 if (RequireCompleteDeclContext(SS, DC)) 1594 return ExprError(); 1595 } else { 1596 DependentID = true; 1597 } 1598 } 1599 1600 if (DependentID) 1601 return ActOnDependentIdExpression(SS, NameInfo, isAddressOfOperand, 1602 TemplateArgs); 1603 1604 bool IvarLookupFollowUp = false; 1605 // Perform the required lookup. 1606 LookupResult R(*this, NameInfo, 1607 (Id.getKind() == UnqualifiedId::IK_ImplicitSelfParam) 1608 ? LookupObjCImplicitSelfParam : LookupOrdinaryName); 1609 if (TemplateArgs) { 1610 // Lookup the template name again to correctly establish the context in 1611 // which it was found. This is really unfortunate as we already did the 1612 // lookup to determine that it was a template name in the first place. If 1613 // this becomes a performance hit, we can work harder to preserve those 1614 // results until we get here but it's likely not worth it. 1615 bool MemberOfUnknownSpecialization; 1616 LookupTemplateName(R, S, SS, QualType(), /*EnteringContext=*/false, 1617 MemberOfUnknownSpecialization); 1618 1619 if (MemberOfUnknownSpecialization || 1620 (R.getResultKind() == LookupResult::NotFoundInCurrentInstantiation)) 1621 return ActOnDependentIdExpression(SS, NameInfo, isAddressOfOperand, 1622 TemplateArgs); 1623 } else { 1624 IvarLookupFollowUp = (!SS.isSet() && II && getCurMethodDecl()); 1625 LookupParsedName(R, S, &SS, !IvarLookupFollowUp); 1626 1627 // If the result might be in a dependent base class, this is a dependent 1628 // id-expression. 1629 if (R.getResultKind() == LookupResult::NotFoundInCurrentInstantiation) 1630 return ActOnDependentIdExpression(SS, NameInfo, isAddressOfOperand, 1631 TemplateArgs); 1632 1633 // If this reference is in an Objective-C method, then we need to do 1634 // some special Objective-C lookup, too. 1635 if (IvarLookupFollowUp) { 1636 ExprResult E(LookupInObjCMethod(R, S, II, true)); 1637 if (E.isInvalid()) 1638 return ExprError(); 1639 1640 if (Expr *Ex = E.takeAs<Expr>()) 1641 return Owned(Ex); 1642 1643 // Synthesize ivars lazily. 1644 if (getLangOptions().ObjCDefaultSynthProperties && 1645 getLangOptions().ObjCNonFragileABI2) { 1646 if (SynthesizeProvisionalIvar(R, II, NameLoc)) { 1647 if (const ObjCPropertyDecl *Property = 1648 canSynthesizeProvisionalIvar(II)) { 1649 Diag(NameLoc, diag::warn_synthesized_ivar_access) << II; 1650 Diag(Property->getLocation(), diag::note_property_declare); 1651 } 1652 return ActOnIdExpression(S, SS, Id, HasTrailingLParen, 1653 isAddressOfOperand); 1654 } 1655 } 1656 // for further use, this must be set to false if in class method. 1657 IvarLookupFollowUp = getCurMethodDecl()->isInstanceMethod(); 1658 } 1659 } 1660 1661 if (R.isAmbiguous()) 1662 return ExprError(); 1663 1664 // Determine whether this name might be a candidate for 1665 // argument-dependent lookup. 1666 bool ADL = UseArgumentDependentLookup(SS, R, HasTrailingLParen); 1667 1668 if (R.empty() && !ADL) { 1669 // Otherwise, this could be an implicitly declared function reference (legal 1670 // in C90, extension in C99, forbidden in C++). 1671 if (HasTrailingLParen && II && !getLangOptions().CPlusPlus) { 1672 NamedDecl *D = ImplicitlyDefineFunction(NameLoc, *II, S); 1673 if (D) R.addDecl(D); 1674 } 1675 1676 // If this name wasn't predeclared and if this is not a function 1677 // call, diagnose the problem. 1678 if (R.empty()) { 1679 if (DiagnoseEmptyLookup(S, SS, R, CTC_Unknown)) 1680 return ExprError(); 1681 1682 assert(!R.empty() && 1683 "DiagnoseEmptyLookup returned false but added no results"); 1684 1685 // If we found an Objective-C instance variable, let 1686 // LookupInObjCMethod build the appropriate expression to 1687 // reference the ivar. 1688 if (ObjCIvarDecl *Ivar = R.getAsSingle<ObjCIvarDecl>()) { 1689 R.clear(); 1690 ExprResult E(LookupInObjCMethod(R, S, Ivar->getIdentifier())); 1691 assert(E.isInvalid() || E.get()); 1692 return move(E); 1693 } 1694 } 1695 } 1696 1697 // This is guaranteed from this point on. 1698 assert(!R.empty() || ADL); 1699 1700 // Check whether this might be a C++ implicit instance member access. 1701 // C++ [class.mfct.non-static]p3: 1702 // When an id-expression that is not part of a class member access 1703 // syntax and not used to form a pointer to member is used in the 1704 // body of a non-static member function of class X, if name lookup 1705 // resolves the name in the id-expression to a non-static non-type 1706 // member of some class C, the id-expression is transformed into a 1707 // class member access expression using (*this) as the 1708 // postfix-expression to the left of the . operator. 1709 // 1710 // But we don't actually need to do this for '&' operands if R 1711 // resolved to a function or overloaded function set, because the 1712 // expression is ill-formed if it actually works out to be a 1713 // non-static member function: 1714 // 1715 // C++ [expr.ref]p4: 1716 // Otherwise, if E1.E2 refers to a non-static member function. . . 1717 // [t]he expression can be used only as the left-hand operand of a 1718 // member function call. 1719 // 1720 // There are other safeguards against such uses, but it's important 1721 // to get this right here so that we don't end up making a 1722 // spuriously dependent expression if we're inside a dependent 1723 // instance method. 1724 if (!R.empty() && (*R.begin())->isCXXClassMember()) { 1725 bool MightBeImplicitMember; 1726 if (!isAddressOfOperand) 1727 MightBeImplicitMember = true; 1728 else if (!SS.isEmpty()) 1729 MightBeImplicitMember = false; 1730 else if (R.isOverloadedResult()) 1731 MightBeImplicitMember = false; 1732 else if (R.isUnresolvableResult()) 1733 MightBeImplicitMember = true; 1734 else 1735 MightBeImplicitMember = isa<FieldDecl>(R.getFoundDecl()) || 1736 isa<IndirectFieldDecl>(R.getFoundDecl()); 1737 1738 if (MightBeImplicitMember) 1739 return BuildPossibleImplicitMemberExpr(SS, R, TemplateArgs); 1740 } 1741 1742 if (TemplateArgs) 1743 return BuildTemplateIdExpr(SS, R, ADL, *TemplateArgs); 1744 1745 return BuildDeclarationNameExpr(SS, R, ADL); 1746} 1747 1748/// BuildQualifiedDeclarationNameExpr - Build a C++ qualified 1749/// declaration name, generally during template instantiation. 1750/// There's a large number of things which don't need to be done along 1751/// this path. 1752ExprResult 1753Sema::BuildQualifiedDeclarationNameExpr(CXXScopeSpec &SS, 1754 const DeclarationNameInfo &NameInfo) { 1755 DeclContext *DC; 1756 if (!(DC = computeDeclContext(SS, false)) || DC->isDependentContext()) 1757 return BuildDependentDeclRefExpr(SS, NameInfo, 0); 1758 1759 if (RequireCompleteDeclContext(SS, DC)) 1760 return ExprError(); 1761 1762 LookupResult R(*this, NameInfo, LookupOrdinaryName); 1763 LookupQualifiedName(R, DC); 1764 1765 if (R.isAmbiguous()) 1766 return ExprError(); 1767 1768 if (R.empty()) { 1769 Diag(NameInfo.getLoc(), diag::err_no_member) 1770 << NameInfo.getName() << DC << SS.getRange(); 1771 return ExprError(); 1772 } 1773 1774 return BuildDeclarationNameExpr(SS, R, /*ADL*/ false); 1775} 1776 1777/// LookupInObjCMethod - The parser has read a name in, and Sema has 1778/// detected that we're currently inside an ObjC method. Perform some 1779/// additional lookup. 1780/// 1781/// Ideally, most of this would be done by lookup, but there's 1782/// actually quite a lot of extra work involved. 1783/// 1784/// Returns a null sentinel to indicate trivial success. 1785ExprResult 1786Sema::LookupInObjCMethod(LookupResult &Lookup, Scope *S, 1787 IdentifierInfo *II, bool AllowBuiltinCreation) { 1788 SourceLocation Loc = Lookup.getNameLoc(); 1789 ObjCMethodDecl *CurMethod = getCurMethodDecl(); 1790 1791 // There are two cases to handle here. 1) scoped lookup could have failed, 1792 // in which case we should look for an ivar. 2) scoped lookup could have 1793 // found a decl, but that decl is outside the current instance method (i.e. 1794 // a global variable). In these two cases, we do a lookup for an ivar with 1795 // this name, if the lookup sucedes, we replace it our current decl. 1796 1797 // If we're in a class method, we don't normally want to look for 1798 // ivars. But if we don't find anything else, and there's an 1799 // ivar, that's an error. 1800 bool IsClassMethod = CurMethod->isClassMethod(); 1801 1802 bool LookForIvars; 1803 if (Lookup.empty()) 1804 LookForIvars = true; 1805 else if (IsClassMethod) 1806 LookForIvars = false; 1807 else 1808 LookForIvars = (Lookup.isSingleResult() && 1809 Lookup.getFoundDecl()->isDefinedOutsideFunctionOrMethod()); 1810 ObjCInterfaceDecl *IFace = 0; 1811 if (LookForIvars) { 1812 IFace = CurMethod->getClassInterface(); 1813 ObjCInterfaceDecl *ClassDeclared; 1814 if (ObjCIvarDecl *IV = IFace->lookupInstanceVariable(II, ClassDeclared)) { 1815 // Diagnose using an ivar in a class method. 1816 if (IsClassMethod) 1817 return ExprError(Diag(Loc, diag::error_ivar_use_in_class_method) 1818 << IV->getDeclName()); 1819 1820 // If we're referencing an invalid decl, just return this as a silent 1821 // error node. The error diagnostic was already emitted on the decl. 1822 if (IV->isInvalidDecl()) 1823 return ExprError(); 1824 1825 // Check if referencing a field with __attribute__((deprecated)). 1826 if (DiagnoseUseOfDecl(IV, Loc)) 1827 return ExprError(); 1828 1829 // Diagnose the use of an ivar outside of the declaring class. 1830 if (IV->getAccessControl() == ObjCIvarDecl::Private && 1831 ClassDeclared != IFace) 1832 Diag(Loc, diag::error_private_ivar_access) << IV->getDeclName(); 1833 1834 // FIXME: This should use a new expr for a direct reference, don't 1835 // turn this into Self->ivar, just return a BareIVarExpr or something. 1836 IdentifierInfo &II = Context.Idents.get("self"); 1837 UnqualifiedId SelfName; 1838 SelfName.setIdentifier(&II, SourceLocation()); 1839 SelfName.setKind(UnqualifiedId::IK_ImplicitSelfParam); 1840 CXXScopeSpec SelfScopeSpec; 1841 ExprResult SelfExpr = ActOnIdExpression(S, SelfScopeSpec, 1842 SelfName, false, false); 1843 if (SelfExpr.isInvalid()) 1844 return ExprError(); 1845 1846 SelfExpr = DefaultLvalueConversion(SelfExpr.take()); 1847 if (SelfExpr.isInvalid()) 1848 return ExprError(); 1849 1850 MarkDeclarationReferenced(Loc, IV); 1851 return Owned(new (Context) 1852 ObjCIvarRefExpr(IV, IV->getType(), Loc, 1853 SelfExpr.take(), true, true)); 1854 } 1855 } else if (CurMethod->isInstanceMethod()) { 1856 // We should warn if a local variable hides an ivar. 1857 ObjCInterfaceDecl *IFace = CurMethod->getClassInterface(); 1858 ObjCInterfaceDecl *ClassDeclared; 1859 if (ObjCIvarDecl *IV = IFace->lookupInstanceVariable(II, ClassDeclared)) { 1860 if (IV->getAccessControl() != ObjCIvarDecl::Private || 1861 IFace == ClassDeclared) 1862 Diag(Loc, diag::warn_ivar_use_hidden) << IV->getDeclName(); 1863 } 1864 } 1865 1866 if (Lookup.empty() && II && AllowBuiltinCreation) { 1867 // FIXME. Consolidate this with similar code in LookupName. 1868 if (unsigned BuiltinID = II->getBuiltinID()) { 1869 if (!(getLangOptions().CPlusPlus && 1870 Context.BuiltinInfo.isPredefinedLibFunction(BuiltinID))) { 1871 NamedDecl *D = LazilyCreateBuiltin((IdentifierInfo *)II, BuiltinID, 1872 S, Lookup.isForRedeclaration(), 1873 Lookup.getNameLoc()); 1874 if (D) Lookup.addDecl(D); 1875 } 1876 } 1877 } 1878 // Sentinel value saying that we didn't do anything special. 1879 return Owned((Expr*) 0); 1880} 1881 1882/// \brief Cast a base object to a member's actual type. 1883/// 1884/// Logically this happens in three phases: 1885/// 1886/// * First we cast from the base type to the naming class. 1887/// The naming class is the class into which we were looking 1888/// when we found the member; it's the qualifier type if a 1889/// qualifier was provided, and otherwise it's the base type. 1890/// 1891/// * Next we cast from the naming class to the declaring class. 1892/// If the member we found was brought into a class's scope by 1893/// a using declaration, this is that class; otherwise it's 1894/// the class declaring the member. 1895/// 1896/// * Finally we cast from the declaring class to the "true" 1897/// declaring class of the member. This conversion does not 1898/// obey access control. 1899ExprResult 1900Sema::PerformObjectMemberConversion(Expr *From, 1901 NestedNameSpecifier *Qualifier, 1902 NamedDecl *FoundDecl, 1903 NamedDecl *Member) { 1904 CXXRecordDecl *RD = dyn_cast<CXXRecordDecl>(Member->getDeclContext()); 1905 if (!RD) 1906 return Owned(From); 1907 1908 QualType DestRecordType; 1909 QualType DestType; 1910 QualType FromRecordType; 1911 QualType FromType = From->getType(); 1912 bool PointerConversions = false; 1913 if (isa<FieldDecl>(Member)) { 1914 DestRecordType = Context.getCanonicalType(Context.getTypeDeclType(RD)); 1915 1916 if (FromType->getAs<PointerType>()) { 1917 DestType = Context.getPointerType(DestRecordType); 1918 FromRecordType = FromType->getPointeeType(); 1919 PointerConversions = true; 1920 } else { 1921 DestType = DestRecordType; 1922 FromRecordType = FromType; 1923 } 1924 } else if (CXXMethodDecl *Method = dyn_cast<CXXMethodDecl>(Member)) { 1925 if (Method->isStatic()) 1926 return Owned(From); 1927 1928 DestType = Method->getThisType(Context); 1929 DestRecordType = DestType->getPointeeType(); 1930 1931 if (FromType->getAs<PointerType>()) { 1932 FromRecordType = FromType->getPointeeType(); 1933 PointerConversions = true; 1934 } else { 1935 FromRecordType = FromType; 1936 DestType = DestRecordType; 1937 } 1938 } else { 1939 // No conversion necessary. 1940 return Owned(From); 1941 } 1942 1943 if (DestType->isDependentType() || FromType->isDependentType()) 1944 return Owned(From); 1945 1946 // If the unqualified types are the same, no conversion is necessary. 1947 if (Context.hasSameUnqualifiedType(FromRecordType, DestRecordType)) 1948 return Owned(From); 1949 1950 SourceRange FromRange = From->getSourceRange(); 1951 SourceLocation FromLoc = FromRange.getBegin(); 1952 1953 ExprValueKind VK = CastCategory(From); 1954 1955 // C++ [class.member.lookup]p8: 1956 // [...] Ambiguities can often be resolved by qualifying a name with its 1957 // class name. 1958 // 1959 // If the member was a qualified name and the qualified referred to a 1960 // specific base subobject type, we'll cast to that intermediate type 1961 // first and then to the object in which the member is declared. That allows 1962 // one to resolve ambiguities in, e.g., a diamond-shaped hierarchy such as: 1963 // 1964 // class Base { public: int x; }; 1965 // class Derived1 : public Base { }; 1966 // class Derived2 : public Base { }; 1967 // class VeryDerived : public Derived1, public Derived2 { void f(); }; 1968 // 1969 // void VeryDerived::f() { 1970 // x = 17; // error: ambiguous base subobjects 1971 // Derived1::x = 17; // okay, pick the Base subobject of Derived1 1972 // } 1973 if (Qualifier) { 1974 QualType QType = QualType(Qualifier->getAsType(), 0); 1975 assert(!QType.isNull() && "lookup done with dependent qualifier?"); 1976 assert(QType->isRecordType() && "lookup done with non-record type"); 1977 1978 QualType QRecordType = QualType(QType->getAs<RecordType>(), 0); 1979 1980 // In C++98, the qualifier type doesn't actually have to be a base 1981 // type of the object type, in which case we just ignore it. 1982 // Otherwise build the appropriate casts. 1983 if (IsDerivedFrom(FromRecordType, QRecordType)) { 1984 CXXCastPath BasePath; 1985 if (CheckDerivedToBaseConversion(FromRecordType, QRecordType, 1986 FromLoc, FromRange, &BasePath)) 1987 return ExprError(); 1988 1989 if (PointerConversions) 1990 QType = Context.getPointerType(QType); 1991 From = ImpCastExprToType(From, QType, CK_UncheckedDerivedToBase, 1992 VK, &BasePath).take(); 1993 1994 FromType = QType; 1995 FromRecordType = QRecordType; 1996 1997 // If the qualifier type was the same as the destination type, 1998 // we're done. 1999 if (Context.hasSameUnqualifiedType(FromRecordType, DestRecordType)) 2000 return Owned(From); 2001 } 2002 } 2003 2004 bool IgnoreAccess = false; 2005 2006 // If we actually found the member through a using declaration, cast 2007 // down to the using declaration's type. 2008 // 2009 // Pointer equality is fine here because only one declaration of a 2010 // class ever has member declarations. 2011 if (FoundDecl->getDeclContext() != Member->getDeclContext()) { 2012 assert(isa<UsingShadowDecl>(FoundDecl)); 2013 QualType URecordType = Context.getTypeDeclType( 2014 cast<CXXRecordDecl>(FoundDecl->getDeclContext())); 2015 2016 // We only need to do this if the naming-class to declaring-class 2017 // conversion is non-trivial. 2018 if (!Context.hasSameUnqualifiedType(FromRecordType, URecordType)) { 2019 assert(IsDerivedFrom(FromRecordType, URecordType)); 2020 CXXCastPath BasePath; 2021 if (CheckDerivedToBaseConversion(FromRecordType, URecordType, 2022 FromLoc, FromRange, &BasePath)) 2023 return ExprError(); 2024 2025 QualType UType = URecordType; 2026 if (PointerConversions) 2027 UType = Context.getPointerType(UType); 2028 From = ImpCastExprToType(From, UType, CK_UncheckedDerivedToBase, 2029 VK, &BasePath).take(); 2030 FromType = UType; 2031 FromRecordType = URecordType; 2032 } 2033 2034 // We don't do access control for the conversion from the 2035 // declaring class to the true declaring class. 2036 IgnoreAccess = true; 2037 } 2038 2039 CXXCastPath BasePath; 2040 if (CheckDerivedToBaseConversion(FromRecordType, DestRecordType, 2041 FromLoc, FromRange, &BasePath, 2042 IgnoreAccess)) 2043 return ExprError(); 2044 2045 return ImpCastExprToType(From, DestType, CK_UncheckedDerivedToBase, 2046 VK, &BasePath); 2047} 2048 2049bool Sema::UseArgumentDependentLookup(const CXXScopeSpec &SS, 2050 const LookupResult &R, 2051 bool HasTrailingLParen) { 2052 // Only when used directly as the postfix-expression of a call. 2053 if (!HasTrailingLParen) 2054 return false; 2055 2056 // Never if a scope specifier was provided. 2057 if (SS.isSet()) 2058 return false; 2059 2060 // Only in C++ or ObjC++. 2061 if (!getLangOptions().CPlusPlus) 2062 return false; 2063 2064 // Turn off ADL when we find certain kinds of declarations during 2065 // normal lookup: 2066 for (LookupResult::iterator I = R.begin(), E = R.end(); I != E; ++I) { 2067 NamedDecl *D = *I; 2068 2069 // C++0x [basic.lookup.argdep]p3: 2070 // -- a declaration of a class member 2071 // Since using decls preserve this property, we check this on the 2072 // original decl. 2073 if (D->isCXXClassMember()) 2074 return false; 2075 2076 // C++0x [basic.lookup.argdep]p3: 2077 // -- a block-scope function declaration that is not a 2078 // using-declaration 2079 // NOTE: we also trigger this for function templates (in fact, we 2080 // don't check the decl type at all, since all other decl types 2081 // turn off ADL anyway). 2082 if (isa<UsingShadowDecl>(D)) 2083 D = cast<UsingShadowDecl>(D)->getTargetDecl(); 2084 else if (D->getDeclContext()->isFunctionOrMethod()) 2085 return false; 2086 2087 // C++0x [basic.lookup.argdep]p3: 2088 // -- a declaration that is neither a function or a function 2089 // template 2090 // And also for builtin functions. 2091 if (isa<FunctionDecl>(D)) { 2092 FunctionDecl *FDecl = cast<FunctionDecl>(D); 2093 2094 // But also builtin functions. 2095 if (FDecl->getBuiltinID() && FDecl->isImplicit()) 2096 return false; 2097 } else if (!isa<FunctionTemplateDecl>(D)) 2098 return false; 2099 } 2100 2101 return true; 2102} 2103 2104 2105/// Diagnoses obvious problems with the use of the given declaration 2106/// as an expression. This is only actually called for lookups that 2107/// were not overloaded, and it doesn't promise that the declaration 2108/// will in fact be used. 2109static bool CheckDeclInExpr(Sema &S, SourceLocation Loc, NamedDecl *D) { 2110 if (isa<TypedefNameDecl>(D)) { 2111 S.Diag(Loc, diag::err_unexpected_typedef) << D->getDeclName(); 2112 return true; 2113 } 2114 2115 if (isa<ObjCInterfaceDecl>(D)) { 2116 S.Diag(Loc, diag::err_unexpected_interface) << D->getDeclName(); 2117 return true; 2118 } 2119 2120 if (isa<NamespaceDecl>(D)) { 2121 S.Diag(Loc, diag::err_unexpected_namespace) << D->getDeclName(); 2122 return true; 2123 } 2124 2125 return false; 2126} 2127 2128ExprResult 2129Sema::BuildDeclarationNameExpr(const CXXScopeSpec &SS, 2130 LookupResult &R, 2131 bool NeedsADL) { 2132 // If this is a single, fully-resolved result and we don't need ADL, 2133 // just build an ordinary singleton decl ref. 2134 if (!NeedsADL && R.isSingleResult() && !R.getAsSingle<FunctionTemplateDecl>()) 2135 return BuildDeclarationNameExpr(SS, R.getLookupNameInfo(), 2136 R.getFoundDecl()); 2137 2138 // We only need to check the declaration if there's exactly one 2139 // result, because in the overloaded case the results can only be 2140 // functions and function templates. 2141 if (R.isSingleResult() && 2142 CheckDeclInExpr(*this, R.getNameLoc(), R.getFoundDecl())) 2143 return ExprError(); 2144 2145 // Otherwise, just build an unresolved lookup expression. Suppress 2146 // any lookup-related diagnostics; we'll hash these out later, when 2147 // we've picked a target. 2148 R.suppressDiagnostics(); 2149 2150 UnresolvedLookupExpr *ULE 2151 = UnresolvedLookupExpr::Create(Context, R.getNamingClass(), 2152 SS.getWithLocInContext(Context), 2153 R.getLookupNameInfo(), 2154 NeedsADL, R.isOverloadedResult(), 2155 R.begin(), R.end()); 2156 2157 return Owned(ULE); 2158} 2159 2160/// \brief Complete semantic analysis for a reference to the given declaration. 2161ExprResult 2162Sema::BuildDeclarationNameExpr(const CXXScopeSpec &SS, 2163 const DeclarationNameInfo &NameInfo, 2164 NamedDecl *D) { 2165 assert(D && "Cannot refer to a NULL declaration"); 2166 assert(!isa<FunctionTemplateDecl>(D) && 2167 "Cannot refer unambiguously to a function template"); 2168 2169 SourceLocation Loc = NameInfo.getLoc(); 2170 if (CheckDeclInExpr(*this, Loc, D)) 2171 return ExprError(); 2172 2173 if (TemplateDecl *Template = dyn_cast<TemplateDecl>(D)) { 2174 // Specifically diagnose references to class templates that are missing 2175 // a template argument list. 2176 Diag(Loc, diag::err_template_decl_ref) 2177 << Template << SS.getRange(); 2178 Diag(Template->getLocation(), diag::note_template_decl_here); 2179 return ExprError(); 2180 } 2181 2182 // Make sure that we're referring to a value. 2183 ValueDecl *VD = dyn_cast<ValueDecl>(D); 2184 if (!VD) { 2185 Diag(Loc, diag::err_ref_non_value) 2186 << D << SS.getRange(); 2187 Diag(D->getLocation(), diag::note_declared_at); 2188 return ExprError(); 2189 } 2190 2191 // Check whether this declaration can be used. Note that we suppress 2192 // this check when we're going to perform argument-dependent lookup 2193 // on this function name, because this might not be the function 2194 // that overload resolution actually selects. 2195 if (DiagnoseUseOfDecl(VD, Loc)) 2196 return ExprError(); 2197 2198 // Only create DeclRefExpr's for valid Decl's. 2199 if (VD->isInvalidDecl()) 2200 return ExprError(); 2201 2202 // Handle members of anonymous structs and unions. If we got here, 2203 // and the reference is to a class member indirect field, then this 2204 // must be the subject of a pointer-to-member expression. 2205 if (IndirectFieldDecl *indirectField = dyn_cast<IndirectFieldDecl>(VD)) 2206 if (!indirectField->isCXXClassMember()) 2207 return BuildAnonymousStructUnionMemberReference(SS, NameInfo.getLoc(), 2208 indirectField); 2209 2210 // If the identifier reference is inside a block, and it refers to a value 2211 // that is outside the block, create a BlockDeclRefExpr instead of a 2212 // DeclRefExpr. This ensures the value is treated as a copy-in snapshot when 2213 // the block is formed. 2214 // 2215 // We do not do this for things like enum constants, global variables, etc, 2216 // as they do not get snapshotted. 2217 // 2218 switch (shouldCaptureValueReference(*this, NameInfo.getLoc(), VD)) { 2219 case CR_Error: 2220 return ExprError(); 2221 2222 case CR_Capture: 2223 assert(!SS.isSet() && "referenced local variable with scope specifier?"); 2224 return BuildBlockDeclRefExpr(*this, VD, NameInfo, /*byref*/ false); 2225 2226 case CR_CaptureByRef: 2227 assert(!SS.isSet() && "referenced local variable with scope specifier?"); 2228 return BuildBlockDeclRefExpr(*this, VD, NameInfo, /*byref*/ true); 2229 2230 case CR_NoCapture: { 2231 // If this reference is not in a block or if the referenced 2232 // variable is within the block, create a normal DeclRefExpr. 2233 2234 QualType type = VD->getType(); 2235 ExprValueKind valueKind = VK_RValue; 2236 2237 switch (D->getKind()) { 2238 // Ignore all the non-ValueDecl kinds. 2239#define ABSTRACT_DECL(kind) 2240#define VALUE(type, base) 2241#define DECL(type, base) \ 2242 case Decl::type: 2243#include "clang/AST/DeclNodes.inc" 2244 llvm_unreachable("invalid value decl kind"); 2245 return ExprError(); 2246 2247 // These shouldn't make it here. 2248 case Decl::ObjCAtDefsField: 2249 case Decl::ObjCIvar: 2250 llvm_unreachable("forming non-member reference to ivar?"); 2251 return ExprError(); 2252 2253 // Enum constants are always r-values and never references. 2254 // Unresolved using declarations are dependent. 2255 case Decl::EnumConstant: 2256 case Decl::UnresolvedUsingValue: 2257 valueKind = VK_RValue; 2258 break; 2259 2260 // Fields and indirect fields that got here must be for 2261 // pointer-to-member expressions; we just call them l-values for 2262 // internal consistency, because this subexpression doesn't really 2263 // exist in the high-level semantics. 2264 case Decl::Field: 2265 case Decl::IndirectField: 2266 assert(getLangOptions().CPlusPlus && 2267 "building reference to field in C?"); 2268 2269 // These can't have reference type in well-formed programs, but 2270 // for internal consistency we do this anyway. 2271 type = type.getNonReferenceType(); 2272 valueKind = VK_LValue; 2273 break; 2274 2275 // Non-type template parameters are either l-values or r-values 2276 // depending on the type. 2277 case Decl::NonTypeTemplateParm: { 2278 if (const ReferenceType *reftype = type->getAs<ReferenceType>()) { 2279 type = reftype->getPointeeType(); 2280 valueKind = VK_LValue; // even if the parameter is an r-value reference 2281 break; 2282 } 2283 2284 // For non-references, we need to strip qualifiers just in case 2285 // the template parameter was declared as 'const int' or whatever. 2286 valueKind = VK_RValue; 2287 type = type.getUnqualifiedType(); 2288 break; 2289 } 2290 2291 case Decl::Var: 2292 // In C, "extern void blah;" is valid and is an r-value. 2293 if (!getLangOptions().CPlusPlus && 2294 !type.hasQualifiers() && 2295 type->isVoidType()) { 2296 valueKind = VK_RValue; 2297 break; 2298 } 2299 // fallthrough 2300 2301 case Decl::ImplicitParam: 2302 case Decl::ParmVar: 2303 // These are always l-values. 2304 valueKind = VK_LValue; 2305 type = type.getNonReferenceType(); 2306 break; 2307 2308 case Decl::Function: { 2309 const FunctionType *fty = type->castAs<FunctionType>(); 2310 2311 // If we're referring to a function with an __unknown_anytype 2312 // result type, make the entire expression __unknown_anytype. 2313 if (fty->getResultType() == Context.UnknownAnyTy) { 2314 type = Context.UnknownAnyTy; 2315 valueKind = VK_RValue; 2316 break; 2317 } 2318 2319 // Functions are l-values in C++. 2320 if (getLangOptions().CPlusPlus) { 2321 valueKind = VK_LValue; 2322 break; 2323 } 2324 2325 // C99 DR 316 says that, if a function type comes from a 2326 // function definition (without a prototype), that type is only 2327 // used for checking compatibility. Therefore, when referencing 2328 // the function, we pretend that we don't have the full function 2329 // type. 2330 if (!cast<FunctionDecl>(VD)->hasPrototype() && 2331 isa<FunctionProtoType>(fty)) 2332 type = Context.getFunctionNoProtoType(fty->getResultType(), 2333 fty->getExtInfo()); 2334 2335 // Functions are r-values in C. 2336 valueKind = VK_RValue; 2337 break; 2338 } 2339 2340 case Decl::CXXMethod: 2341 // If we're referring to a method with an __unknown_anytype 2342 // result type, make the entire expression __unknown_anytype. 2343 // This should only be possible with a type written directly. 2344 if (const FunctionProtoType *proto = dyn_cast<FunctionProtoType>(VD->getType())) 2345 if (proto->getResultType() == Context.UnknownAnyTy) { 2346 type = Context.UnknownAnyTy; 2347 valueKind = VK_RValue; 2348 break; 2349 } 2350 2351 // C++ methods are l-values if static, r-values if non-static. 2352 if (cast<CXXMethodDecl>(VD)->isStatic()) { 2353 valueKind = VK_LValue; 2354 break; 2355 } 2356 // fallthrough 2357 2358 case Decl::CXXConversion: 2359 case Decl::CXXDestructor: 2360 case Decl::CXXConstructor: 2361 valueKind = VK_RValue; 2362 break; 2363 } 2364 2365 return BuildDeclRefExpr(VD, type, valueKind, NameInfo, &SS); 2366 } 2367 2368 } 2369 2370 llvm_unreachable("unknown capture result"); 2371 return ExprError(); 2372} 2373 2374ExprResult Sema::ActOnPredefinedExpr(SourceLocation Loc, tok::TokenKind Kind) { 2375 PredefinedExpr::IdentType IT; 2376 2377 switch (Kind) { 2378 default: assert(0 && "Unknown simple primary expr!"); 2379 case tok::kw___func__: IT = PredefinedExpr::Func; break; // [C99 6.4.2.2] 2380 case tok::kw___FUNCTION__: IT = PredefinedExpr::Function; break; 2381 case tok::kw___PRETTY_FUNCTION__: IT = PredefinedExpr::PrettyFunction; break; 2382 } 2383 2384 // Pre-defined identifiers are of type char[x], where x is the length of the 2385 // string. 2386 2387 Decl *currentDecl = getCurFunctionOrMethodDecl(); 2388 if (!currentDecl && getCurBlock()) 2389 currentDecl = getCurBlock()->TheDecl; 2390 if (!currentDecl) { 2391 Diag(Loc, diag::ext_predef_outside_function); 2392 currentDecl = Context.getTranslationUnitDecl(); 2393 } 2394 2395 QualType ResTy; 2396 if (cast<DeclContext>(currentDecl)->isDependentContext()) { 2397 ResTy = Context.DependentTy; 2398 } else { 2399 unsigned Length = PredefinedExpr::ComputeName(IT, currentDecl).length(); 2400 2401 llvm::APInt LengthI(32, Length + 1); 2402 ResTy = Context.CharTy.withConst(); 2403 ResTy = Context.getConstantArrayType(ResTy, LengthI, ArrayType::Normal, 0); 2404 } 2405 return Owned(new (Context) PredefinedExpr(Loc, ResTy, IT)); 2406} 2407 2408ExprResult Sema::ActOnCharacterConstant(const Token &Tok) { 2409 llvm::SmallString<16> CharBuffer; 2410 bool Invalid = false; 2411 llvm::StringRef ThisTok = PP.getSpelling(Tok, CharBuffer, &Invalid); 2412 if (Invalid) 2413 return ExprError(); 2414 2415 CharLiteralParser Literal(ThisTok.begin(), ThisTok.end(), Tok.getLocation(), 2416 PP); 2417 if (Literal.hadError()) 2418 return ExprError(); 2419 2420 QualType Ty; 2421 if (!getLangOptions().CPlusPlus) 2422 Ty = Context.IntTy; // 'x' and L'x' -> int in C. 2423 else if (Literal.isWide()) 2424 Ty = Context.WCharTy; // L'x' -> wchar_t in C++. 2425 else if (Literal.isMultiChar()) 2426 Ty = Context.IntTy; // 'wxyz' -> int in C++. 2427 else 2428 Ty = Context.CharTy; // 'x' -> char in C++ 2429 2430 return Owned(new (Context) CharacterLiteral(Literal.getValue(), 2431 Literal.isWide(), 2432 Ty, Tok.getLocation())); 2433} 2434 2435ExprResult Sema::ActOnNumericConstant(const Token &Tok) { 2436 // Fast path for a single digit (which is quite common). A single digit 2437 // cannot have a trigraph, escaped newline, radix prefix, or type suffix. 2438 if (Tok.getLength() == 1) { 2439 const char Val = PP.getSpellingOfSingleCharacterNumericConstant(Tok); 2440 unsigned IntSize = Context.Target.getIntWidth(); 2441 return Owned(IntegerLiteral::Create(Context, llvm::APInt(IntSize, Val-'0'), 2442 Context.IntTy, Tok.getLocation())); 2443 } 2444 2445 llvm::SmallString<512> IntegerBuffer; 2446 // Add padding so that NumericLiteralParser can overread by one character. 2447 IntegerBuffer.resize(Tok.getLength()+1); 2448 const char *ThisTokBegin = &IntegerBuffer[0]; 2449 2450 // Get the spelling of the token, which eliminates trigraphs, etc. 2451 bool Invalid = false; 2452 unsigned ActualLength = PP.getSpelling(Tok, ThisTokBegin, &Invalid); 2453 if (Invalid) 2454 return ExprError(); 2455 2456 NumericLiteralParser Literal(ThisTokBegin, ThisTokBegin+ActualLength, 2457 Tok.getLocation(), PP); 2458 if (Literal.hadError) 2459 return ExprError(); 2460 2461 Expr *Res; 2462 2463 if (Literal.isFloatingLiteral()) { 2464 QualType Ty; 2465 if (Literal.isFloat) 2466 Ty = Context.FloatTy; 2467 else if (!Literal.isLong) 2468 Ty = Context.DoubleTy; 2469 else 2470 Ty = Context.LongDoubleTy; 2471 2472 const llvm::fltSemantics &Format = Context.getFloatTypeSemantics(Ty); 2473 2474 using llvm::APFloat; 2475 APFloat Val(Format); 2476 2477 APFloat::opStatus result = Literal.GetFloatValue(Val); 2478 2479 // Overflow is always an error, but underflow is only an error if 2480 // we underflowed to zero (APFloat reports denormals as underflow). 2481 if ((result & APFloat::opOverflow) || 2482 ((result & APFloat::opUnderflow) && Val.isZero())) { 2483 unsigned diagnostic; 2484 llvm::SmallString<20> buffer; 2485 if (result & APFloat::opOverflow) { 2486 diagnostic = diag::warn_float_overflow; 2487 APFloat::getLargest(Format).toString(buffer); 2488 } else { 2489 diagnostic = diag::warn_float_underflow; 2490 APFloat::getSmallest(Format).toString(buffer); 2491 } 2492 2493 Diag(Tok.getLocation(), diagnostic) 2494 << Ty 2495 << llvm::StringRef(buffer.data(), buffer.size()); 2496 } 2497 2498 bool isExact = (result == APFloat::opOK); 2499 Res = FloatingLiteral::Create(Context, Val, isExact, Ty, Tok.getLocation()); 2500 2501 if (Ty == Context.DoubleTy) { 2502 if (getLangOptions().SinglePrecisionConstants) { 2503 Res = ImpCastExprToType(Res, Context.FloatTy, CK_FloatingCast).take(); 2504 } else if (getLangOptions().OpenCL && !getOpenCLOptions().cl_khr_fp64) { 2505 Diag(Tok.getLocation(), diag::warn_double_const_requires_fp64); 2506 Res = ImpCastExprToType(Res, Context.FloatTy, CK_FloatingCast).take(); 2507 } 2508 } 2509 } else if (!Literal.isIntegerLiteral()) { 2510 return ExprError(); 2511 } else { 2512 QualType Ty; 2513 2514 // long long is a C99 feature. 2515 if (!getLangOptions().C99 && !getLangOptions().CPlusPlus0x && 2516 Literal.isLongLong) 2517 Diag(Tok.getLocation(), diag::ext_longlong); 2518 2519 // Get the value in the widest-possible width. 2520 llvm::APInt ResultVal(Context.Target.getIntMaxTWidth(), 0); 2521 2522 if (Literal.GetIntegerValue(ResultVal)) { 2523 // If this value didn't fit into uintmax_t, warn and force to ull. 2524 Diag(Tok.getLocation(), diag::warn_integer_too_large); 2525 Ty = Context.UnsignedLongLongTy; 2526 assert(Context.getTypeSize(Ty) == ResultVal.getBitWidth() && 2527 "long long is not intmax_t?"); 2528 } else { 2529 // If this value fits into a ULL, try to figure out what else it fits into 2530 // according to the rules of C99 6.4.4.1p5. 2531 2532 // Octal, Hexadecimal, and integers with a U suffix are allowed to 2533 // be an unsigned int. 2534 bool AllowUnsigned = Literal.isUnsigned || Literal.getRadix() != 10; 2535 2536 // Check from smallest to largest, picking the smallest type we can. 2537 unsigned Width = 0; 2538 if (!Literal.isLong && !Literal.isLongLong) { 2539 // Are int/unsigned possibilities? 2540 unsigned IntSize = Context.Target.getIntWidth(); 2541 2542 // Does it fit in a unsigned int? 2543 if (ResultVal.isIntN(IntSize)) { 2544 // Does it fit in a signed int? 2545 if (!Literal.isUnsigned && ResultVal[IntSize-1] == 0) 2546 Ty = Context.IntTy; 2547 else if (AllowUnsigned) 2548 Ty = Context.UnsignedIntTy; 2549 Width = IntSize; 2550 } 2551 } 2552 2553 // Are long/unsigned long possibilities? 2554 if (Ty.isNull() && !Literal.isLongLong) { 2555 unsigned LongSize = Context.Target.getLongWidth(); 2556 2557 // Does it fit in a unsigned long? 2558 if (ResultVal.isIntN(LongSize)) { 2559 // Does it fit in a signed long? 2560 if (!Literal.isUnsigned && ResultVal[LongSize-1] == 0) 2561 Ty = Context.LongTy; 2562 else if (AllowUnsigned) 2563 Ty = Context.UnsignedLongTy; 2564 Width = LongSize; 2565 } 2566 } 2567 2568 // Finally, check long long if needed. 2569 if (Ty.isNull()) { 2570 unsigned LongLongSize = Context.Target.getLongLongWidth(); 2571 2572 // Does it fit in a unsigned long long? 2573 if (ResultVal.isIntN(LongLongSize)) { 2574 // Does it fit in a signed long long? 2575 // To be compatible with MSVC, hex integer literals ending with the 2576 // LL or i64 suffix are always signed in Microsoft mode. 2577 if (!Literal.isUnsigned && (ResultVal[LongLongSize-1] == 0 || 2578 (getLangOptions().Microsoft && Literal.isLongLong))) 2579 Ty = Context.LongLongTy; 2580 else if (AllowUnsigned) 2581 Ty = Context.UnsignedLongLongTy; 2582 Width = LongLongSize; 2583 } 2584 } 2585 2586 // If we still couldn't decide a type, we probably have something that 2587 // does not fit in a signed long long, but has no U suffix. 2588 if (Ty.isNull()) { 2589 Diag(Tok.getLocation(), diag::warn_integer_too_large_for_signed); 2590 Ty = Context.UnsignedLongLongTy; 2591 Width = Context.Target.getLongLongWidth(); 2592 } 2593 2594 if (ResultVal.getBitWidth() != Width) 2595 ResultVal = ResultVal.trunc(Width); 2596 } 2597 Res = IntegerLiteral::Create(Context, ResultVal, Ty, Tok.getLocation()); 2598 } 2599 2600 // If this is an imaginary literal, create the ImaginaryLiteral wrapper. 2601 if (Literal.isImaginary) 2602 Res = new (Context) ImaginaryLiteral(Res, 2603 Context.getComplexType(Res->getType())); 2604 2605 return Owned(Res); 2606} 2607 2608ExprResult Sema::ActOnParenExpr(SourceLocation L, 2609 SourceLocation R, Expr *E) { 2610 assert((E != 0) && "ActOnParenExpr() missing expr"); 2611 return Owned(new (Context) ParenExpr(L, R, E)); 2612} 2613 2614static bool CheckVecStepTraitOperandType(Sema &S, QualType T, 2615 SourceLocation Loc, 2616 SourceRange ArgRange) { 2617 // [OpenCL 1.1 6.11.12] "The vec_step built-in function takes a built-in 2618 // scalar or vector data type argument..." 2619 // Every built-in scalar type (OpenCL 1.1 6.1.1) is either an arithmetic 2620 // type (C99 6.2.5p18) or void. 2621 if (!(T->isArithmeticType() || T->isVoidType() || T->isVectorType())) { 2622 S.Diag(Loc, diag::err_vecstep_non_scalar_vector_type) 2623 << T << ArgRange; 2624 return true; 2625 } 2626 2627 assert((T->isVoidType() || !T->isIncompleteType()) && 2628 "Scalar types should always be complete"); 2629 return false; 2630} 2631 2632static bool CheckExtensionTraitOperandType(Sema &S, QualType T, 2633 SourceLocation Loc, 2634 SourceRange ArgRange, 2635 UnaryExprOrTypeTrait TraitKind) { 2636 // C99 6.5.3.4p1: 2637 if (T->isFunctionType()) { 2638 // alignof(function) is allowed as an extension. 2639 if (TraitKind == UETT_SizeOf) 2640 S.Diag(Loc, diag::ext_sizeof_function_type) << ArgRange; 2641 return false; 2642 } 2643 2644 // Allow sizeof(void)/alignof(void) as an extension. 2645 if (T->isVoidType()) { 2646 S.Diag(Loc, diag::ext_sizeof_void_type) << TraitKind << ArgRange; 2647 return false; 2648 } 2649 2650 return true; 2651} 2652 2653static bool CheckObjCTraitOperandConstraints(Sema &S, QualType T, 2654 SourceLocation Loc, 2655 SourceRange ArgRange, 2656 UnaryExprOrTypeTrait TraitKind) { 2657 // Reject sizeof(interface) and sizeof(interface<proto>) in 64-bit mode. 2658 if (S.LangOpts.ObjCNonFragileABI && T->isObjCObjectType()) { 2659 S.Diag(Loc, diag::err_sizeof_nonfragile_interface) 2660 << T << (TraitKind == UETT_SizeOf) 2661 << ArgRange; 2662 return true; 2663 } 2664 2665 return false; 2666} 2667 2668/// \brief Check the constrains on expression operands to unary type expression 2669/// and type traits. 2670/// 2671/// Completes any types necessary and validates the constraints on the operand 2672/// expression. The logic mostly mirrors the type-based overload, but may modify 2673/// the expression as it completes the type for that expression through template 2674/// instantiation, etc. 2675bool Sema::CheckUnaryExprOrTypeTraitOperand(Expr *Op, 2676 UnaryExprOrTypeTrait ExprKind) { 2677 QualType ExprTy = Op->getType(); 2678 2679 // C++ [expr.sizeof]p2: "When applied to a reference or a reference type, 2680 // the result is the size of the referenced type." 2681 // C++ [expr.alignof]p3: "When alignof is applied to a reference type, the 2682 // result shall be the alignment of the referenced type." 2683 if (const ReferenceType *Ref = ExprTy->getAs<ReferenceType>()) 2684 ExprTy = Ref->getPointeeType(); 2685 2686 if (ExprKind == UETT_VecStep) 2687 return CheckVecStepTraitOperandType(*this, ExprTy, Op->getExprLoc(), 2688 Op->getSourceRange()); 2689 2690 // Whitelist some types as extensions 2691 if (!CheckExtensionTraitOperandType(*this, ExprTy, Op->getExprLoc(), 2692 Op->getSourceRange(), ExprKind)) 2693 return false; 2694 2695 if (RequireCompleteExprType(Op, 2696 PDiag(diag::err_sizeof_alignof_incomplete_type) 2697 << ExprKind << Op->getSourceRange(), 2698 std::make_pair(SourceLocation(), PDiag(0)))) 2699 return true; 2700 2701 // Completeing the expression's type may have changed it. 2702 ExprTy = Op->getType(); 2703 if (const ReferenceType *Ref = ExprTy->getAs<ReferenceType>()) 2704 ExprTy = Ref->getPointeeType(); 2705 2706 if (CheckObjCTraitOperandConstraints(*this, ExprTy, Op->getExprLoc(), 2707 Op->getSourceRange(), ExprKind)) 2708 return true; 2709 2710 if (ExprKind == UETT_SizeOf) { 2711 if (DeclRefExpr *DeclRef = dyn_cast<DeclRefExpr>(Op->IgnoreParens())) { 2712 if (ParmVarDecl *PVD = dyn_cast<ParmVarDecl>(DeclRef->getFoundDecl())) { 2713 QualType OType = PVD->getOriginalType(); 2714 QualType Type = PVD->getType(); 2715 if (Type->isPointerType() && OType->isArrayType()) { 2716 Diag(Op->getExprLoc(), diag::warn_sizeof_array_param) 2717 << Type << OType; 2718 Diag(PVD->getLocation(), diag::note_declared_at); 2719 } 2720 } 2721 } 2722 } 2723 2724 return false; 2725} 2726 2727/// \brief Check the constraints on operands to unary expression and type 2728/// traits. 2729/// 2730/// This will complete any types necessary, and validate the various constraints 2731/// on those operands. 2732/// 2733/// The UsualUnaryConversions() function is *not* called by this routine. 2734/// C99 6.3.2.1p[2-4] all state: 2735/// Except when it is the operand of the sizeof operator ... 2736/// 2737/// C++ [expr.sizeof]p4 2738/// The lvalue-to-rvalue, array-to-pointer, and function-to-pointer 2739/// standard conversions are not applied to the operand of sizeof. 2740/// 2741/// This policy is followed for all of the unary trait expressions. 2742bool Sema::CheckUnaryExprOrTypeTraitOperand(QualType exprType, 2743 SourceLocation OpLoc, 2744 SourceRange ExprRange, 2745 UnaryExprOrTypeTrait ExprKind) { 2746 if (exprType->isDependentType()) 2747 return false; 2748 2749 // C++ [expr.sizeof]p2: "When applied to a reference or a reference type, 2750 // the result is the size of the referenced type." 2751 // C++ [expr.alignof]p3: "When alignof is applied to a reference type, the 2752 // result shall be the alignment of the referenced type." 2753 if (const ReferenceType *Ref = exprType->getAs<ReferenceType>()) 2754 exprType = Ref->getPointeeType(); 2755 2756 if (ExprKind == UETT_VecStep) 2757 return CheckVecStepTraitOperandType(*this, exprType, OpLoc, ExprRange); 2758 2759 // Whitelist some types as extensions 2760 if (!CheckExtensionTraitOperandType(*this, exprType, OpLoc, ExprRange, 2761 ExprKind)) 2762 return false; 2763 2764 if (RequireCompleteType(OpLoc, exprType, 2765 PDiag(diag::err_sizeof_alignof_incomplete_type) 2766 << ExprKind << ExprRange)) 2767 return true; 2768 2769 if (CheckObjCTraitOperandConstraints(*this, exprType, OpLoc, ExprRange, 2770 ExprKind)) 2771 return true; 2772 2773 return false; 2774} 2775 2776static bool CheckAlignOfExpr(Sema &S, Expr *E) { 2777 E = E->IgnoreParens(); 2778 2779 // alignof decl is always ok. 2780 if (isa<DeclRefExpr>(E)) 2781 return false; 2782 2783 // Cannot know anything else if the expression is dependent. 2784 if (E->isTypeDependent()) 2785 return false; 2786 2787 if (E->getBitField()) { 2788 S.Diag(E->getExprLoc(), diag::err_sizeof_alignof_bitfield) 2789 << 1 << E->getSourceRange(); 2790 return true; 2791 } 2792 2793 // Alignment of a field access is always okay, so long as it isn't a 2794 // bit-field. 2795 if (MemberExpr *ME = dyn_cast<MemberExpr>(E)) 2796 if (isa<FieldDecl>(ME->getMemberDecl())) 2797 return false; 2798 2799 return S.CheckUnaryExprOrTypeTraitOperand(E, UETT_AlignOf); 2800} 2801 2802bool Sema::CheckVecStepExpr(Expr *E) { 2803 E = E->IgnoreParens(); 2804 2805 // Cannot know anything else if the expression is dependent. 2806 if (E->isTypeDependent()) 2807 return false; 2808 2809 return CheckUnaryExprOrTypeTraitOperand(E, UETT_VecStep); 2810} 2811 2812/// \brief Build a sizeof or alignof expression given a type operand. 2813ExprResult 2814Sema::CreateUnaryExprOrTypeTraitExpr(TypeSourceInfo *TInfo, 2815 SourceLocation OpLoc, 2816 UnaryExprOrTypeTrait ExprKind, 2817 SourceRange R) { 2818 if (!TInfo) 2819 return ExprError(); 2820 2821 QualType T = TInfo->getType(); 2822 2823 if (!T->isDependentType() && 2824 CheckUnaryExprOrTypeTraitOperand(T, OpLoc, R, ExprKind)) 2825 return ExprError(); 2826 2827 // C99 6.5.3.4p4: the type (an unsigned integer type) is size_t. 2828 return Owned(new (Context) UnaryExprOrTypeTraitExpr(ExprKind, TInfo, 2829 Context.getSizeType(), 2830 OpLoc, R.getEnd())); 2831} 2832 2833/// \brief Build a sizeof or alignof expression given an expression 2834/// operand. 2835ExprResult 2836Sema::CreateUnaryExprOrTypeTraitExpr(Expr *E, SourceLocation OpLoc, 2837 UnaryExprOrTypeTrait ExprKind) { 2838 ExprResult PE = CheckPlaceholderExpr(E); 2839 if (PE.isInvalid()) 2840 return ExprError(); 2841 2842 E = PE.get(); 2843 2844 // Verify that the operand is valid. 2845 bool isInvalid = false; 2846 if (E->isTypeDependent()) { 2847 // Delay type-checking for type-dependent expressions. 2848 } else if (ExprKind == UETT_AlignOf) { 2849 isInvalid = CheckAlignOfExpr(*this, E); 2850 } else if (ExprKind == UETT_VecStep) { 2851 isInvalid = CheckVecStepExpr(E); 2852 } else if (E->getBitField()) { // C99 6.5.3.4p1. 2853 Diag(E->getExprLoc(), diag::err_sizeof_alignof_bitfield) << 0; 2854 isInvalid = true; 2855 } else { 2856 isInvalid = CheckUnaryExprOrTypeTraitOperand(E, UETT_SizeOf); 2857 } 2858 2859 if (isInvalid) 2860 return ExprError(); 2861 2862 // C99 6.5.3.4p4: the type (an unsigned integer type) is size_t. 2863 return Owned(new (Context) UnaryExprOrTypeTraitExpr( 2864 ExprKind, E, Context.getSizeType(), OpLoc, 2865 E->getSourceRange().getEnd())); 2866} 2867 2868/// ActOnUnaryExprOrTypeTraitExpr - Handle @c sizeof(type) and @c sizeof @c 2869/// expr and the same for @c alignof and @c __alignof 2870/// Note that the ArgRange is invalid if isType is false. 2871ExprResult 2872Sema::ActOnUnaryExprOrTypeTraitExpr(SourceLocation OpLoc, 2873 UnaryExprOrTypeTrait ExprKind, bool isType, 2874 void *TyOrEx, const SourceRange &ArgRange) { 2875 // If error parsing type, ignore. 2876 if (TyOrEx == 0) return ExprError(); 2877 2878 if (isType) { 2879 TypeSourceInfo *TInfo; 2880 (void) GetTypeFromParser(ParsedType::getFromOpaquePtr(TyOrEx), &TInfo); 2881 return CreateUnaryExprOrTypeTraitExpr(TInfo, OpLoc, ExprKind, ArgRange); 2882 } 2883 2884 Expr *ArgEx = (Expr *)TyOrEx; 2885 ExprResult Result = CreateUnaryExprOrTypeTraitExpr(ArgEx, OpLoc, ExprKind); 2886 return move(Result); 2887} 2888 2889static QualType CheckRealImagOperand(Sema &S, ExprResult &V, SourceLocation Loc, 2890 bool isReal) { 2891 if (V.get()->isTypeDependent()) 2892 return S.Context.DependentTy; 2893 2894 // _Real and _Imag are only l-values for normal l-values. 2895 if (V.get()->getObjectKind() != OK_Ordinary) { 2896 V = S.DefaultLvalueConversion(V.take()); 2897 if (V.isInvalid()) 2898 return QualType(); 2899 } 2900 2901 // These operators return the element type of a complex type. 2902 if (const ComplexType *CT = V.get()->getType()->getAs<ComplexType>()) 2903 return CT->getElementType(); 2904 2905 // Otherwise they pass through real integer and floating point types here. 2906 if (V.get()->getType()->isArithmeticType()) 2907 return V.get()->getType(); 2908 2909 // Test for placeholders. 2910 ExprResult PR = S.CheckPlaceholderExpr(V.get()); 2911 if (PR.isInvalid()) return QualType(); 2912 if (PR.get() != V.get()) { 2913 V = move(PR); 2914 return CheckRealImagOperand(S, V, Loc, isReal); 2915 } 2916 2917 // Reject anything else. 2918 S.Diag(Loc, diag::err_realimag_invalid_type) << V.get()->getType() 2919 << (isReal ? "__real" : "__imag"); 2920 return QualType(); 2921} 2922 2923 2924 2925ExprResult 2926Sema::ActOnPostfixUnaryOp(Scope *S, SourceLocation OpLoc, 2927 tok::TokenKind Kind, Expr *Input) { 2928 UnaryOperatorKind Opc; 2929 switch (Kind) { 2930 default: assert(0 && "Unknown unary op!"); 2931 case tok::plusplus: Opc = UO_PostInc; break; 2932 case tok::minusminus: Opc = UO_PostDec; break; 2933 } 2934 2935 return BuildUnaryOp(S, OpLoc, Opc, Input); 2936} 2937 2938ExprResult 2939Sema::ActOnArraySubscriptExpr(Scope *S, Expr *Base, SourceLocation LLoc, 2940 Expr *Idx, SourceLocation RLoc) { 2941 // Since this might be a postfix expression, get rid of ParenListExprs. 2942 ExprResult Result = MaybeConvertParenListExprToParenExpr(S, Base); 2943 if (Result.isInvalid()) return ExprError(); 2944 Base = Result.take(); 2945 2946 Expr *LHSExp = Base, *RHSExp = Idx; 2947 2948 if (getLangOptions().CPlusPlus && 2949 (LHSExp->isTypeDependent() || RHSExp->isTypeDependent())) { 2950 return Owned(new (Context) ArraySubscriptExpr(LHSExp, RHSExp, 2951 Context.DependentTy, 2952 VK_LValue, OK_Ordinary, 2953 RLoc)); 2954 } 2955 2956 if (getLangOptions().CPlusPlus && 2957 (LHSExp->getType()->isRecordType() || 2958 LHSExp->getType()->isEnumeralType() || 2959 RHSExp->getType()->isRecordType() || 2960 RHSExp->getType()->isEnumeralType())) { 2961 return CreateOverloadedArraySubscriptExpr(LLoc, RLoc, Base, Idx); 2962 } 2963 2964 return CreateBuiltinArraySubscriptExpr(Base, LLoc, Idx, RLoc); 2965} 2966 2967 2968ExprResult 2969Sema::CreateBuiltinArraySubscriptExpr(Expr *Base, SourceLocation LLoc, 2970 Expr *Idx, SourceLocation RLoc) { 2971 Expr *LHSExp = Base; 2972 Expr *RHSExp = Idx; 2973 2974 // Perform default conversions. 2975 if (!LHSExp->getType()->getAs<VectorType>()) { 2976 ExprResult Result = DefaultFunctionArrayLvalueConversion(LHSExp); 2977 if (Result.isInvalid()) 2978 return ExprError(); 2979 LHSExp = Result.take(); 2980 } 2981 ExprResult Result = DefaultFunctionArrayLvalueConversion(RHSExp); 2982 if (Result.isInvalid()) 2983 return ExprError(); 2984 RHSExp = Result.take(); 2985 2986 QualType LHSTy = LHSExp->getType(), RHSTy = RHSExp->getType(); 2987 ExprValueKind VK = VK_LValue; 2988 ExprObjectKind OK = OK_Ordinary; 2989 2990 // C99 6.5.2.1p2: the expression e1[e2] is by definition precisely equivalent 2991 // to the expression *((e1)+(e2)). This means the array "Base" may actually be 2992 // in the subscript position. As a result, we need to derive the array base 2993 // and index from the expression types. 2994 Expr *BaseExpr, *IndexExpr; 2995 QualType ResultType; 2996 if (LHSTy->isDependentType() || RHSTy->isDependentType()) { 2997 BaseExpr = LHSExp; 2998 IndexExpr = RHSExp; 2999 ResultType = Context.DependentTy; 3000 } else if (const PointerType *PTy = LHSTy->getAs<PointerType>()) { 3001 BaseExpr = LHSExp; 3002 IndexExpr = RHSExp; 3003 ResultType = PTy->getPointeeType(); 3004 } else if (const PointerType *PTy = RHSTy->getAs<PointerType>()) { 3005 // Handle the uncommon case of "123[Ptr]". 3006 BaseExpr = RHSExp; 3007 IndexExpr = LHSExp; 3008 ResultType = PTy->getPointeeType(); 3009 } else if (const ObjCObjectPointerType *PTy = 3010 LHSTy->getAs<ObjCObjectPointerType>()) { 3011 BaseExpr = LHSExp; 3012 IndexExpr = RHSExp; 3013 ResultType = PTy->getPointeeType(); 3014 } else if (const ObjCObjectPointerType *PTy = 3015 RHSTy->getAs<ObjCObjectPointerType>()) { 3016 // Handle the uncommon case of "123[Ptr]". 3017 BaseExpr = RHSExp; 3018 IndexExpr = LHSExp; 3019 ResultType = PTy->getPointeeType(); 3020 } else if (const VectorType *VTy = LHSTy->getAs<VectorType>()) { 3021 BaseExpr = LHSExp; // vectors: V[123] 3022 IndexExpr = RHSExp; 3023 VK = LHSExp->getValueKind(); 3024 if (VK != VK_RValue) 3025 OK = OK_VectorComponent; 3026 3027 // FIXME: need to deal with const... 3028 ResultType = VTy->getElementType(); 3029 } else if (LHSTy->isArrayType()) { 3030 // If we see an array that wasn't promoted by 3031 // DefaultFunctionArrayLvalueConversion, it must be an array that 3032 // wasn't promoted because of the C90 rule that doesn't 3033 // allow promoting non-lvalue arrays. Warn, then 3034 // force the promotion here. 3035 Diag(LHSExp->getLocStart(), diag::ext_subscript_non_lvalue) << 3036 LHSExp->getSourceRange(); 3037 LHSExp = ImpCastExprToType(LHSExp, Context.getArrayDecayedType(LHSTy), 3038 CK_ArrayToPointerDecay).take(); 3039 LHSTy = LHSExp->getType(); 3040 3041 BaseExpr = LHSExp; 3042 IndexExpr = RHSExp; 3043 ResultType = LHSTy->getAs<PointerType>()->getPointeeType(); 3044 } else if (RHSTy->isArrayType()) { 3045 // Same as previous, except for 123[f().a] case 3046 Diag(RHSExp->getLocStart(), diag::ext_subscript_non_lvalue) << 3047 RHSExp->getSourceRange(); 3048 RHSExp = ImpCastExprToType(RHSExp, Context.getArrayDecayedType(RHSTy), 3049 CK_ArrayToPointerDecay).take(); 3050 RHSTy = RHSExp->getType(); 3051 3052 BaseExpr = RHSExp; 3053 IndexExpr = LHSExp; 3054 ResultType = RHSTy->getAs<PointerType>()->getPointeeType(); 3055 } else { 3056 return ExprError(Diag(LLoc, diag::err_typecheck_subscript_value) 3057 << LHSExp->getSourceRange() << RHSExp->getSourceRange()); 3058 } 3059 // C99 6.5.2.1p1 3060 if (!IndexExpr->getType()->isIntegerType() && !IndexExpr->isTypeDependent()) 3061 return ExprError(Diag(LLoc, diag::err_typecheck_subscript_not_integer) 3062 << IndexExpr->getSourceRange()); 3063 3064 if ((IndexExpr->getType()->isSpecificBuiltinType(BuiltinType::Char_S) || 3065 IndexExpr->getType()->isSpecificBuiltinType(BuiltinType::Char_U)) 3066 && !IndexExpr->isTypeDependent()) 3067 Diag(LLoc, diag::warn_subscript_is_char) << IndexExpr->getSourceRange(); 3068 3069 // C99 6.5.2.1p1: "shall have type "pointer to *object* type". Similarly, 3070 // C++ [expr.sub]p1: The type "T" shall be a completely-defined object 3071 // type. Note that Functions are not objects, and that (in C99 parlance) 3072 // incomplete types are not object types. 3073 if (ResultType->isFunctionType()) { 3074 Diag(BaseExpr->getLocStart(), diag::err_subscript_function_type) 3075 << ResultType << BaseExpr->getSourceRange(); 3076 return ExprError(); 3077 } 3078 3079 if (ResultType->isVoidType() && !getLangOptions().CPlusPlus) { 3080 // GNU extension: subscripting on pointer to void 3081 Diag(LLoc, diag::ext_gnu_subscript_void_type) 3082 << BaseExpr->getSourceRange(); 3083 3084 // C forbids expressions of unqualified void type from being l-values. 3085 // See IsCForbiddenLValueType. 3086 if (!ResultType.hasQualifiers()) VK = VK_RValue; 3087 } else if (!ResultType->isDependentType() && 3088 RequireCompleteType(LLoc, ResultType, 3089 PDiag(diag::err_subscript_incomplete_type) 3090 << BaseExpr->getSourceRange())) 3091 return ExprError(); 3092 3093 // Diagnose bad cases where we step over interface counts. 3094 if (ResultType->isObjCObjectType() && LangOpts.ObjCNonFragileABI) { 3095 Diag(LLoc, diag::err_subscript_nonfragile_interface) 3096 << ResultType << BaseExpr->getSourceRange(); 3097 return ExprError(); 3098 } 3099 3100 assert(VK == VK_RValue || LangOpts.CPlusPlus || 3101 !ResultType.isCForbiddenLValueType()); 3102 3103 return Owned(new (Context) ArraySubscriptExpr(LHSExp, RHSExp, 3104 ResultType, VK, OK, RLoc)); 3105} 3106 3107ExprResult Sema::BuildCXXDefaultArgExpr(SourceLocation CallLoc, 3108 FunctionDecl *FD, 3109 ParmVarDecl *Param) { 3110 if (Param->hasUnparsedDefaultArg()) { 3111 Diag(CallLoc, 3112 diag::err_use_of_default_argument_to_function_declared_later) << 3113 FD << cast<CXXRecordDecl>(FD->getDeclContext())->getDeclName(); 3114 Diag(UnparsedDefaultArgLocs[Param], 3115 diag::note_default_argument_declared_here); 3116 return ExprError(); 3117 } 3118 3119 if (Param->hasUninstantiatedDefaultArg()) { 3120 Expr *UninstExpr = Param->getUninstantiatedDefaultArg(); 3121 3122 // Instantiate the expression. 3123 MultiLevelTemplateArgumentList ArgList 3124 = getTemplateInstantiationArgs(FD, 0, /*RelativeToPrimary=*/true); 3125 3126 std::pair<const TemplateArgument *, unsigned> Innermost 3127 = ArgList.getInnermost(); 3128 InstantiatingTemplate Inst(*this, CallLoc, Param, Innermost.first, 3129 Innermost.second); 3130 3131 ExprResult Result; 3132 { 3133 // C++ [dcl.fct.default]p5: 3134 // The names in the [default argument] expression are bound, and 3135 // the semantic constraints are checked, at the point where the 3136 // default argument expression appears. 3137 ContextRAII SavedContext(*this, FD); 3138 Result = SubstExpr(UninstExpr, ArgList); 3139 } 3140 if (Result.isInvalid()) 3141 return ExprError(); 3142 3143 // Check the expression as an initializer for the parameter. 3144 InitializedEntity Entity 3145 = InitializedEntity::InitializeParameter(Context, Param); 3146 InitializationKind Kind 3147 = InitializationKind::CreateCopy(Param->getLocation(), 3148 /*FIXME:EqualLoc*/UninstExpr->getSourceRange().getBegin()); 3149 Expr *ResultE = Result.takeAs<Expr>(); 3150 3151 InitializationSequence InitSeq(*this, Entity, Kind, &ResultE, 1); 3152 Result = InitSeq.Perform(*this, Entity, Kind, 3153 MultiExprArg(*this, &ResultE, 1)); 3154 if (Result.isInvalid()) 3155 return ExprError(); 3156 3157 // Build the default argument expression. 3158 return Owned(CXXDefaultArgExpr::Create(Context, CallLoc, Param, 3159 Result.takeAs<Expr>())); 3160 } 3161 3162 // If the default expression creates temporaries, we need to 3163 // push them to the current stack of expression temporaries so they'll 3164 // be properly destroyed. 3165 // FIXME: We should really be rebuilding the default argument with new 3166 // bound temporaries; see the comment in PR5810. 3167 for (unsigned i = 0, e = Param->getNumDefaultArgTemporaries(); i != e; ++i) { 3168 CXXTemporary *Temporary = Param->getDefaultArgTemporary(i); 3169 MarkDeclarationReferenced(Param->getDefaultArg()->getLocStart(), 3170 const_cast<CXXDestructorDecl*>(Temporary->getDestructor())); 3171 ExprTemporaries.push_back(Temporary); 3172 ExprNeedsCleanups = true; 3173 } 3174 3175 // We already type-checked the argument, so we know it works. 3176 // Just mark all of the declarations in this potentially-evaluated expression 3177 // as being "referenced". 3178 MarkDeclarationsReferencedInExpr(Param->getDefaultArg()); 3179 return Owned(CXXDefaultArgExpr::Create(Context, CallLoc, Param)); 3180} 3181 3182/// ConvertArgumentsForCall - Converts the arguments specified in 3183/// Args/NumArgs to the parameter types of the function FDecl with 3184/// function prototype Proto. Call is the call expression itself, and 3185/// Fn is the function expression. For a C++ member function, this 3186/// routine does not attempt to convert the object argument. Returns 3187/// true if the call is ill-formed. 3188bool 3189Sema::ConvertArgumentsForCall(CallExpr *Call, Expr *Fn, 3190 FunctionDecl *FDecl, 3191 const FunctionProtoType *Proto, 3192 Expr **Args, unsigned NumArgs, 3193 SourceLocation RParenLoc) { 3194 // Bail out early if calling a builtin with custom typechecking. 3195 // We don't need to do this in the 3196 if (FDecl) 3197 if (unsigned ID = FDecl->getBuiltinID()) 3198 if (Context.BuiltinInfo.hasCustomTypechecking(ID)) 3199 return false; 3200 3201 // C99 6.5.2.2p7 - the arguments are implicitly converted, as if by 3202 // assignment, to the types of the corresponding parameter, ... 3203 unsigned NumArgsInProto = Proto->getNumArgs(); 3204 bool Invalid = false; 3205 3206 // If too few arguments are available (and we don't have default 3207 // arguments for the remaining parameters), don't make the call. 3208 if (NumArgs < NumArgsInProto) { 3209 if (!FDecl || NumArgs < FDecl->getMinRequiredArguments()) 3210 return Diag(RParenLoc, diag::err_typecheck_call_too_few_args) 3211 << Fn->getType()->isBlockPointerType() 3212 << NumArgsInProto << NumArgs << Fn->getSourceRange(); 3213 Call->setNumArgs(Context, NumArgsInProto); 3214 } 3215 3216 // If too many are passed and not variadic, error on the extras and drop 3217 // them. 3218 if (NumArgs > NumArgsInProto) { 3219 if (!Proto->isVariadic()) { 3220 Diag(Args[NumArgsInProto]->getLocStart(), 3221 diag::err_typecheck_call_too_many_args) 3222 << Fn->getType()->isBlockPointerType() 3223 << NumArgsInProto << NumArgs << Fn->getSourceRange() 3224 << SourceRange(Args[NumArgsInProto]->getLocStart(), 3225 Args[NumArgs-1]->getLocEnd()); 3226 3227 // Emit the location of the prototype. 3228 if (FDecl && !FDecl->getBuiltinID()) 3229 Diag(FDecl->getLocStart(), 3230 diag::note_typecheck_call_too_many_args) 3231 << FDecl; 3232 3233 // This deletes the extra arguments. 3234 Call->setNumArgs(Context, NumArgsInProto); 3235 return true; 3236 } 3237 } 3238 llvm::SmallVector<Expr *, 8> AllArgs; 3239 VariadicCallType CallType = 3240 Proto->isVariadic() ? VariadicFunction : VariadicDoesNotApply; 3241 if (Fn->getType()->isBlockPointerType()) 3242 CallType = VariadicBlock; // Block 3243 else if (isa<MemberExpr>(Fn)) 3244 CallType = VariadicMethod; 3245 Invalid = GatherArgumentsForCall(Call->getSourceRange().getBegin(), FDecl, 3246 Proto, 0, Args, NumArgs, AllArgs, CallType); 3247 if (Invalid) 3248 return true; 3249 unsigned TotalNumArgs = AllArgs.size(); 3250 for (unsigned i = 0; i < TotalNumArgs; ++i) 3251 Call->setArg(i, AllArgs[i]); 3252 3253 return false; 3254} 3255 3256bool Sema::GatherArgumentsForCall(SourceLocation CallLoc, 3257 FunctionDecl *FDecl, 3258 const FunctionProtoType *Proto, 3259 unsigned FirstProtoArg, 3260 Expr **Args, unsigned NumArgs, 3261 llvm::SmallVector<Expr *, 8> &AllArgs, 3262 VariadicCallType CallType) { 3263 unsigned NumArgsInProto = Proto->getNumArgs(); 3264 unsigned NumArgsToCheck = NumArgs; 3265 bool Invalid = false; 3266 if (NumArgs != NumArgsInProto) 3267 // Use default arguments for missing arguments 3268 NumArgsToCheck = NumArgsInProto; 3269 unsigned ArgIx = 0; 3270 // Continue to check argument types (even if we have too few/many args). 3271 for (unsigned i = FirstProtoArg; i != NumArgsToCheck; i++) { 3272 QualType ProtoArgType = Proto->getArgType(i); 3273 3274 Expr *Arg; 3275 if (ArgIx < NumArgs) { 3276 Arg = Args[ArgIx++]; 3277 3278 if (RequireCompleteType(Arg->getSourceRange().getBegin(), 3279 ProtoArgType, 3280 PDiag(diag::err_call_incomplete_argument) 3281 << Arg->getSourceRange())) 3282 return true; 3283 3284 // Pass the argument 3285 ParmVarDecl *Param = 0; 3286 if (FDecl && i < FDecl->getNumParams()) 3287 Param = FDecl->getParamDecl(i); 3288 3289 InitializedEntity Entity = 3290 Param? InitializedEntity::InitializeParameter(Context, Param) 3291 : InitializedEntity::InitializeParameter(Context, ProtoArgType, 3292 Proto->isArgConsumed(i)); 3293 ExprResult ArgE = PerformCopyInitialization(Entity, 3294 SourceLocation(), 3295 Owned(Arg)); 3296 if (ArgE.isInvalid()) 3297 return true; 3298 3299 Arg = ArgE.takeAs<Expr>(); 3300 } else { 3301 ParmVarDecl *Param = FDecl->getParamDecl(i); 3302 3303 ExprResult ArgExpr = 3304 BuildCXXDefaultArgExpr(CallLoc, FDecl, Param); 3305 if (ArgExpr.isInvalid()) 3306 return true; 3307 3308 Arg = ArgExpr.takeAs<Expr>(); 3309 } 3310 AllArgs.push_back(Arg); 3311 } 3312 3313 // If this is a variadic call, handle args passed through "...". 3314 if (CallType != VariadicDoesNotApply) { 3315 3316 // Assume that extern "C" functions with variadic arguments that 3317 // return __unknown_anytype aren't *really* variadic. 3318 if (Proto->getResultType() == Context.UnknownAnyTy && 3319 FDecl && FDecl->isExternC()) { 3320 for (unsigned i = ArgIx; i != NumArgs; ++i) { 3321 ExprResult arg; 3322 if (isa<ExplicitCastExpr>(Args[i]->IgnoreParens())) 3323 arg = DefaultFunctionArrayLvalueConversion(Args[i]); 3324 else 3325 arg = DefaultVariadicArgumentPromotion(Args[i], CallType, FDecl); 3326 Invalid |= arg.isInvalid(); 3327 AllArgs.push_back(arg.take()); 3328 } 3329 3330 // Otherwise do argument promotion, (C99 6.5.2.2p7). 3331 } else { 3332 for (unsigned i = ArgIx; i != NumArgs; ++i) { 3333 ExprResult Arg = DefaultVariadicArgumentPromotion(Args[i], CallType, FDecl); 3334 Invalid |= Arg.isInvalid(); 3335 AllArgs.push_back(Arg.take()); 3336 } 3337 } 3338 } 3339 return Invalid; 3340} 3341 3342/// Given a function expression of unknown-any type, try to rebuild it 3343/// to have a function type. 3344static ExprResult rebuildUnknownAnyFunction(Sema &S, Expr *fn); 3345 3346/// ActOnCallExpr - Handle a call to Fn with the specified array of arguments. 3347/// This provides the location of the left/right parens and a list of comma 3348/// locations. 3349ExprResult 3350Sema::ActOnCallExpr(Scope *S, Expr *Fn, SourceLocation LParenLoc, 3351 MultiExprArg args, SourceLocation RParenLoc, 3352 Expr *ExecConfig) { 3353 unsigned NumArgs = args.size(); 3354 3355 // Since this might be a postfix expression, get rid of ParenListExprs. 3356 ExprResult Result = MaybeConvertParenListExprToParenExpr(S, Fn); 3357 if (Result.isInvalid()) return ExprError(); 3358 Fn = Result.take(); 3359 3360 Expr **Args = args.release(); 3361 3362 if (getLangOptions().CPlusPlus) { 3363 // If this is a pseudo-destructor expression, build the call immediately. 3364 if (isa<CXXPseudoDestructorExpr>(Fn)) { 3365 if (NumArgs > 0) { 3366 // Pseudo-destructor calls should not have any arguments. 3367 Diag(Fn->getLocStart(), diag::err_pseudo_dtor_call_with_args) 3368 << FixItHint::CreateRemoval( 3369 SourceRange(Args[0]->getLocStart(), 3370 Args[NumArgs-1]->getLocEnd())); 3371 3372 NumArgs = 0; 3373 } 3374 3375 return Owned(new (Context) CallExpr(Context, Fn, 0, 0, Context.VoidTy, 3376 VK_RValue, RParenLoc)); 3377 } 3378 3379 // Determine whether this is a dependent call inside a C++ template, 3380 // in which case we won't do any semantic analysis now. 3381 // FIXME: Will need to cache the results of name lookup (including ADL) in 3382 // Fn. 3383 bool Dependent = false; 3384 if (Fn->isTypeDependent()) 3385 Dependent = true; 3386 else if (Expr::hasAnyTypeDependentArguments(Args, NumArgs)) 3387 Dependent = true; 3388 3389 if (Dependent) { 3390 if (ExecConfig) { 3391 return Owned(new (Context) CUDAKernelCallExpr( 3392 Context, Fn, cast<CallExpr>(ExecConfig), Args, NumArgs, 3393 Context.DependentTy, VK_RValue, RParenLoc)); 3394 } else { 3395 return Owned(new (Context) CallExpr(Context, Fn, Args, NumArgs, 3396 Context.DependentTy, VK_RValue, 3397 RParenLoc)); 3398 } 3399 } 3400 3401 // Determine whether this is a call to an object (C++ [over.call.object]). 3402 if (Fn->getType()->isRecordType()) 3403 return Owned(BuildCallToObjectOfClassType(S, Fn, LParenLoc, Args, NumArgs, 3404 RParenLoc)); 3405 3406 if (Fn->getType() == Context.UnknownAnyTy) { 3407 ExprResult result = rebuildUnknownAnyFunction(*this, Fn); 3408 if (result.isInvalid()) return ExprError(); 3409 Fn = result.take(); 3410 } 3411 3412 if (Fn->getType() == Context.BoundMemberTy) { 3413 return BuildCallToMemberFunction(S, Fn, LParenLoc, Args, NumArgs, 3414 RParenLoc); 3415 } 3416 } 3417 3418 // Check for overloaded calls. This can happen even in C due to extensions. 3419 if (Fn->getType() == Context.OverloadTy) { 3420 OverloadExpr::FindResult find = OverloadExpr::find(Fn); 3421 3422 // We aren't supposed to apply this logic if there's an '&' involved. 3423 if (!find.IsAddressOfOperand) { 3424 OverloadExpr *ovl = find.Expression; 3425 if (isa<UnresolvedLookupExpr>(ovl)) { 3426 UnresolvedLookupExpr *ULE = cast<UnresolvedLookupExpr>(ovl); 3427 return BuildOverloadedCallExpr(S, Fn, ULE, LParenLoc, Args, NumArgs, 3428 RParenLoc, ExecConfig); 3429 } else { 3430 return BuildCallToMemberFunction(S, Fn, LParenLoc, Args, NumArgs, 3431 RParenLoc); 3432 } 3433 } 3434 } 3435 3436 // If we're directly calling a function, get the appropriate declaration. 3437 3438 Expr *NakedFn = Fn->IgnoreParens(); 3439 3440 NamedDecl *NDecl = 0; 3441 if (UnaryOperator *UnOp = dyn_cast<UnaryOperator>(NakedFn)) 3442 if (UnOp->getOpcode() == UO_AddrOf) 3443 NakedFn = UnOp->getSubExpr()->IgnoreParens(); 3444 3445 if (isa<DeclRefExpr>(NakedFn)) 3446 NDecl = cast<DeclRefExpr>(NakedFn)->getDecl(); 3447 else if (isa<MemberExpr>(NakedFn)) 3448 NDecl = cast<MemberExpr>(NakedFn)->getMemberDecl(); 3449 3450 return BuildResolvedCallExpr(Fn, NDecl, LParenLoc, Args, NumArgs, RParenLoc, 3451 ExecConfig); 3452} 3453 3454ExprResult 3455Sema::ActOnCUDAExecConfigExpr(Scope *S, SourceLocation LLLLoc, 3456 MultiExprArg execConfig, SourceLocation GGGLoc) { 3457 FunctionDecl *ConfigDecl = Context.getcudaConfigureCallDecl(); 3458 if (!ConfigDecl) 3459 return ExprError(Diag(LLLLoc, diag::err_undeclared_var_use) 3460 << "cudaConfigureCall"); 3461 QualType ConfigQTy = ConfigDecl->getType(); 3462 3463 DeclRefExpr *ConfigDR = new (Context) DeclRefExpr( 3464 ConfigDecl, ConfigQTy, VK_LValue, LLLLoc); 3465 3466 return ActOnCallExpr(S, ConfigDR, LLLLoc, execConfig, GGGLoc, 0); 3467} 3468 3469/// ActOnAsTypeExpr - create a new asType (bitcast) from the arguments. 3470/// 3471/// __builtin_astype( value, dst type ) 3472/// 3473ExprResult Sema::ActOnAsTypeExpr(Expr *expr, ParsedType destty, 3474 SourceLocation BuiltinLoc, 3475 SourceLocation RParenLoc) { 3476 ExprValueKind VK = VK_RValue; 3477 ExprObjectKind OK = OK_Ordinary; 3478 QualType DstTy = GetTypeFromParser(destty); 3479 QualType SrcTy = expr->getType(); 3480 if (Context.getTypeSize(DstTy) != Context.getTypeSize(SrcTy)) 3481 return ExprError(Diag(BuiltinLoc, 3482 diag::err_invalid_astype_of_different_size) 3483 << DstTy 3484 << SrcTy 3485 << expr->getSourceRange()); 3486 return Owned(new (Context) AsTypeExpr(expr, DstTy, VK, OK, BuiltinLoc, RParenLoc)); 3487} 3488 3489/// BuildResolvedCallExpr - Build a call to a resolved expression, 3490/// i.e. an expression not of \p OverloadTy. The expression should 3491/// unary-convert to an expression of function-pointer or 3492/// block-pointer type. 3493/// 3494/// \param NDecl the declaration being called, if available 3495ExprResult 3496Sema::BuildResolvedCallExpr(Expr *Fn, NamedDecl *NDecl, 3497 SourceLocation LParenLoc, 3498 Expr **Args, unsigned NumArgs, 3499 SourceLocation RParenLoc, 3500 Expr *Config) { 3501 FunctionDecl *FDecl = dyn_cast_or_null<FunctionDecl>(NDecl); 3502 3503 // Promote the function operand. 3504 ExprResult Result = UsualUnaryConversions(Fn); 3505 if (Result.isInvalid()) 3506 return ExprError(); 3507 Fn = Result.take(); 3508 3509 // Make the call expr early, before semantic checks. This guarantees cleanup 3510 // of arguments and function on error. 3511 CallExpr *TheCall; 3512 if (Config) { 3513 TheCall = new (Context) CUDAKernelCallExpr(Context, Fn, 3514 cast<CallExpr>(Config), 3515 Args, NumArgs, 3516 Context.BoolTy, 3517 VK_RValue, 3518 RParenLoc); 3519 } else { 3520 TheCall = new (Context) CallExpr(Context, Fn, 3521 Args, NumArgs, 3522 Context.BoolTy, 3523 VK_RValue, 3524 RParenLoc); 3525 } 3526 3527 unsigned BuiltinID = (FDecl ? FDecl->getBuiltinID() : 0); 3528 3529 // Bail out early if calling a builtin with custom typechecking. 3530 if (BuiltinID && Context.BuiltinInfo.hasCustomTypechecking(BuiltinID)) 3531 return CheckBuiltinFunctionCall(BuiltinID, TheCall); 3532 3533 retry: 3534 const FunctionType *FuncT; 3535 if (const PointerType *PT = Fn->getType()->getAs<PointerType>()) { 3536 // C99 6.5.2.2p1 - "The expression that denotes the called function shall 3537 // have type pointer to function". 3538 FuncT = PT->getPointeeType()->getAs<FunctionType>(); 3539 if (FuncT == 0) 3540 return ExprError(Diag(LParenLoc, diag::err_typecheck_call_not_function) 3541 << Fn->getType() << Fn->getSourceRange()); 3542 } else if (const BlockPointerType *BPT = 3543 Fn->getType()->getAs<BlockPointerType>()) { 3544 FuncT = BPT->getPointeeType()->castAs<FunctionType>(); 3545 } else { 3546 // Handle calls to expressions of unknown-any type. 3547 if (Fn->getType() == Context.UnknownAnyTy) { 3548 ExprResult rewrite = rebuildUnknownAnyFunction(*this, Fn); 3549 if (rewrite.isInvalid()) return ExprError(); 3550 Fn = rewrite.take(); 3551 TheCall->setCallee(Fn); 3552 goto retry; 3553 } 3554 3555 return ExprError(Diag(LParenLoc, diag::err_typecheck_call_not_function) 3556 << Fn->getType() << Fn->getSourceRange()); 3557 } 3558 3559 if (getLangOptions().CUDA) { 3560 if (Config) { 3561 // CUDA: Kernel calls must be to global functions 3562 if (FDecl && !FDecl->hasAttr<CUDAGlobalAttr>()) 3563 return ExprError(Diag(LParenLoc,diag::err_kern_call_not_global_function) 3564 << FDecl->getName() << Fn->getSourceRange()); 3565 3566 // CUDA: Kernel function must have 'void' return type 3567 if (!FuncT->getResultType()->isVoidType()) 3568 return ExprError(Diag(LParenLoc, diag::err_kern_type_not_void_return) 3569 << Fn->getType() << Fn->getSourceRange()); 3570 } 3571 } 3572 3573 // Check for a valid return type 3574 if (CheckCallReturnType(FuncT->getResultType(), 3575 Fn->getSourceRange().getBegin(), TheCall, 3576 FDecl)) 3577 return ExprError(); 3578 3579 // We know the result type of the call, set it. 3580 TheCall->setType(FuncT->getCallResultType(Context)); 3581 TheCall->setValueKind(Expr::getValueKindForType(FuncT->getResultType())); 3582 3583 if (const FunctionProtoType *Proto = dyn_cast<FunctionProtoType>(FuncT)) { 3584 if (ConvertArgumentsForCall(TheCall, Fn, FDecl, Proto, Args, NumArgs, 3585 RParenLoc)) 3586 return ExprError(); 3587 } else { 3588 assert(isa<FunctionNoProtoType>(FuncT) && "Unknown FunctionType!"); 3589 3590 if (FDecl) { 3591 // Check if we have too few/too many template arguments, based 3592 // on our knowledge of the function definition. 3593 const FunctionDecl *Def = 0; 3594 if (FDecl->hasBody(Def) && NumArgs != Def->param_size()) { 3595 const FunctionProtoType *Proto 3596 = Def->getType()->getAs<FunctionProtoType>(); 3597 if (!Proto || !(Proto->isVariadic() && NumArgs >= Def->param_size())) 3598 Diag(RParenLoc, diag::warn_call_wrong_number_of_arguments) 3599 << (NumArgs > Def->param_size()) << FDecl << Fn->getSourceRange(); 3600 } 3601 3602 // If the function we're calling isn't a function prototype, but we have 3603 // a function prototype from a prior declaratiom, use that prototype. 3604 if (!FDecl->hasPrototype()) 3605 Proto = FDecl->getType()->getAs<FunctionProtoType>(); 3606 } 3607 3608 // Promote the arguments (C99 6.5.2.2p6). 3609 for (unsigned i = 0; i != NumArgs; i++) { 3610 Expr *Arg = Args[i]; 3611 3612 if (Proto && i < Proto->getNumArgs()) { 3613 InitializedEntity Entity 3614 = InitializedEntity::InitializeParameter(Context, 3615 Proto->getArgType(i), 3616 Proto->isArgConsumed(i)); 3617 ExprResult ArgE = PerformCopyInitialization(Entity, 3618 SourceLocation(), 3619 Owned(Arg)); 3620 if (ArgE.isInvalid()) 3621 return true; 3622 3623 Arg = ArgE.takeAs<Expr>(); 3624 3625 } else { 3626 ExprResult ArgE = DefaultArgumentPromotion(Arg); 3627 3628 if (ArgE.isInvalid()) 3629 return true; 3630 3631 Arg = ArgE.takeAs<Expr>(); 3632 } 3633 3634 if (RequireCompleteType(Arg->getSourceRange().getBegin(), 3635 Arg->getType(), 3636 PDiag(diag::err_call_incomplete_argument) 3637 << Arg->getSourceRange())) 3638 return ExprError(); 3639 3640 TheCall->setArg(i, Arg); 3641 } 3642 } 3643 3644 if (CXXMethodDecl *Method = dyn_cast_or_null<CXXMethodDecl>(FDecl)) 3645 if (!Method->isStatic()) 3646 return ExprError(Diag(LParenLoc, diag::err_member_call_without_object) 3647 << Fn->getSourceRange()); 3648 3649 // Check for sentinels 3650 if (NDecl) 3651 DiagnoseSentinelCalls(NDecl, LParenLoc, Args, NumArgs); 3652 3653 // Do special checking on direct calls to functions. 3654 if (FDecl) { 3655 if (CheckFunctionCall(FDecl, TheCall)) 3656 return ExprError(); 3657 3658 if (BuiltinID) 3659 return CheckBuiltinFunctionCall(BuiltinID, TheCall); 3660 } else if (NDecl) { 3661 if (CheckBlockCall(NDecl, TheCall)) 3662 return ExprError(); 3663 } 3664 3665 return MaybeBindToTemporary(TheCall); 3666} 3667 3668ExprResult 3669Sema::ActOnCompoundLiteral(SourceLocation LParenLoc, ParsedType Ty, 3670 SourceLocation RParenLoc, Expr *InitExpr) { 3671 assert((Ty != 0) && "ActOnCompoundLiteral(): missing type"); 3672 // FIXME: put back this assert when initializers are worked out. 3673 //assert((InitExpr != 0) && "ActOnCompoundLiteral(): missing expression"); 3674 3675 TypeSourceInfo *TInfo; 3676 QualType literalType = GetTypeFromParser(Ty, &TInfo); 3677 if (!TInfo) 3678 TInfo = Context.getTrivialTypeSourceInfo(literalType); 3679 3680 return BuildCompoundLiteralExpr(LParenLoc, TInfo, RParenLoc, InitExpr); 3681} 3682 3683ExprResult 3684Sema::BuildCompoundLiteralExpr(SourceLocation LParenLoc, TypeSourceInfo *TInfo, 3685 SourceLocation RParenLoc, Expr *literalExpr) { 3686 QualType literalType = TInfo->getType(); 3687 3688 if (literalType->isArrayType()) { 3689 if (RequireCompleteType(LParenLoc, Context.getBaseElementType(literalType), 3690 PDiag(diag::err_illegal_decl_array_incomplete_type) 3691 << SourceRange(LParenLoc, 3692 literalExpr->getSourceRange().getEnd()))) 3693 return ExprError(); 3694 if (literalType->isVariableArrayType()) 3695 return ExprError(Diag(LParenLoc, diag::err_variable_object_no_init) 3696 << SourceRange(LParenLoc, literalExpr->getSourceRange().getEnd())); 3697 } else if (!literalType->isDependentType() && 3698 RequireCompleteType(LParenLoc, literalType, 3699 PDiag(diag::err_typecheck_decl_incomplete_type) 3700 << SourceRange(LParenLoc, 3701 literalExpr->getSourceRange().getEnd()))) 3702 return ExprError(); 3703 3704 InitializedEntity Entity 3705 = InitializedEntity::InitializeTemporary(literalType); 3706 InitializationKind Kind 3707 = InitializationKind::CreateCStyleCast(LParenLoc, 3708 SourceRange(LParenLoc, RParenLoc)); 3709 InitializationSequence InitSeq(*this, Entity, Kind, &literalExpr, 1); 3710 ExprResult Result = InitSeq.Perform(*this, Entity, Kind, 3711 MultiExprArg(*this, &literalExpr, 1), 3712 &literalType); 3713 if (Result.isInvalid()) 3714 return ExprError(); 3715 literalExpr = Result.get(); 3716 3717 bool isFileScope = getCurFunctionOrMethodDecl() == 0; 3718 if (isFileScope) { // 6.5.2.5p3 3719 if (CheckForConstantInitializer(literalExpr, literalType)) 3720 return ExprError(); 3721 } 3722 3723 // In C, compound literals are l-values for some reason. 3724 ExprValueKind VK = getLangOptions().CPlusPlus ? VK_RValue : VK_LValue; 3725 3726 return MaybeBindToTemporary( 3727 new (Context) CompoundLiteralExpr(LParenLoc, TInfo, literalType, 3728 VK, literalExpr, isFileScope)); 3729} 3730 3731ExprResult 3732Sema::ActOnInitList(SourceLocation LBraceLoc, MultiExprArg initlist, 3733 SourceLocation RBraceLoc) { 3734 unsigned NumInit = initlist.size(); 3735 Expr **InitList = initlist.release(); 3736 3737 // Semantic analysis for initializers is done by ActOnDeclarator() and 3738 // CheckInitializer() - it requires knowledge of the object being intialized. 3739 3740 InitListExpr *E = new (Context) InitListExpr(Context, LBraceLoc, InitList, 3741 NumInit, RBraceLoc); 3742 E->setType(Context.VoidTy); // FIXME: just a place holder for now. 3743 return Owned(E); 3744} 3745 3746/// Prepares for a scalar cast, performing all the necessary stages 3747/// except the final cast and returning the kind required. 3748static CastKind PrepareScalarCast(Sema &S, ExprResult &Src, QualType DestTy) { 3749 // Both Src and Dest are scalar types, i.e. arithmetic or pointer. 3750 // Also, callers should have filtered out the invalid cases with 3751 // pointers. Everything else should be possible. 3752 3753 QualType SrcTy = Src.get()->getType(); 3754 if (S.Context.hasSameUnqualifiedType(SrcTy, DestTy)) 3755 return CK_NoOp; 3756 3757 switch (SrcTy->getScalarTypeKind()) { 3758 case Type::STK_MemberPointer: 3759 llvm_unreachable("member pointer type in C"); 3760 3761 case Type::STK_Pointer: 3762 switch (DestTy->getScalarTypeKind()) { 3763 case Type::STK_Pointer: 3764 return DestTy->isObjCObjectPointerType() ? 3765 CK_AnyPointerToObjCPointerCast : 3766 CK_BitCast; 3767 case Type::STK_Bool: 3768 return CK_PointerToBoolean; 3769 case Type::STK_Integral: 3770 return CK_PointerToIntegral; 3771 case Type::STK_Floating: 3772 case Type::STK_FloatingComplex: 3773 case Type::STK_IntegralComplex: 3774 case Type::STK_MemberPointer: 3775 llvm_unreachable("illegal cast from pointer"); 3776 } 3777 break; 3778 3779 case Type::STK_Bool: // casting from bool is like casting from an integer 3780 case Type::STK_Integral: 3781 switch (DestTy->getScalarTypeKind()) { 3782 case Type::STK_Pointer: 3783 if (Src.get()->isNullPointerConstant(S.Context, Expr::NPC_ValueDependentIsNull)) 3784 return CK_NullToPointer; 3785 return CK_IntegralToPointer; 3786 case Type::STK_Bool: 3787 return CK_IntegralToBoolean; 3788 case Type::STK_Integral: 3789 return CK_IntegralCast; 3790 case Type::STK_Floating: 3791 return CK_IntegralToFloating; 3792 case Type::STK_IntegralComplex: 3793 Src = S.ImpCastExprToType(Src.take(), DestTy->getAs<ComplexType>()->getElementType(), 3794 CK_IntegralCast); 3795 return CK_IntegralRealToComplex; 3796 case Type::STK_FloatingComplex: 3797 Src = S.ImpCastExprToType(Src.take(), DestTy->getAs<ComplexType>()->getElementType(), 3798 CK_IntegralToFloating); 3799 return CK_FloatingRealToComplex; 3800 case Type::STK_MemberPointer: 3801 llvm_unreachable("member pointer type in C"); 3802 } 3803 break; 3804 3805 case Type::STK_Floating: 3806 switch (DestTy->getScalarTypeKind()) { 3807 case Type::STK_Floating: 3808 return CK_FloatingCast; 3809 case Type::STK_Bool: 3810 return CK_FloatingToBoolean; 3811 case Type::STK_Integral: 3812 return CK_FloatingToIntegral; 3813 case Type::STK_FloatingComplex: 3814 Src = S.ImpCastExprToType(Src.take(), DestTy->getAs<ComplexType>()->getElementType(), 3815 CK_FloatingCast); 3816 return CK_FloatingRealToComplex; 3817 case Type::STK_IntegralComplex: 3818 Src = S.ImpCastExprToType(Src.take(), DestTy->getAs<ComplexType>()->getElementType(), 3819 CK_FloatingToIntegral); 3820 return CK_IntegralRealToComplex; 3821 case Type::STK_Pointer: 3822 llvm_unreachable("valid float->pointer cast?"); 3823 case Type::STK_MemberPointer: 3824 llvm_unreachable("member pointer type in C"); 3825 } 3826 break; 3827 3828 case Type::STK_FloatingComplex: 3829 switch (DestTy->getScalarTypeKind()) { 3830 case Type::STK_FloatingComplex: 3831 return CK_FloatingComplexCast; 3832 case Type::STK_IntegralComplex: 3833 return CK_FloatingComplexToIntegralComplex; 3834 case Type::STK_Floating: { 3835 QualType ET = SrcTy->getAs<ComplexType>()->getElementType(); 3836 if (S.Context.hasSameType(ET, DestTy)) 3837 return CK_FloatingComplexToReal; 3838 Src = S.ImpCastExprToType(Src.take(), ET, CK_FloatingComplexToReal); 3839 return CK_FloatingCast; 3840 } 3841 case Type::STK_Bool: 3842 return CK_FloatingComplexToBoolean; 3843 case Type::STK_Integral: 3844 Src = S.ImpCastExprToType(Src.take(), SrcTy->getAs<ComplexType>()->getElementType(), 3845 CK_FloatingComplexToReal); 3846 return CK_FloatingToIntegral; 3847 case Type::STK_Pointer: 3848 llvm_unreachable("valid complex float->pointer cast?"); 3849 case Type::STK_MemberPointer: 3850 llvm_unreachable("member pointer type in C"); 3851 } 3852 break; 3853 3854 case Type::STK_IntegralComplex: 3855 switch (DestTy->getScalarTypeKind()) { 3856 case Type::STK_FloatingComplex: 3857 return CK_IntegralComplexToFloatingComplex; 3858 case Type::STK_IntegralComplex: 3859 return CK_IntegralComplexCast; 3860 case Type::STK_Integral: { 3861 QualType ET = SrcTy->getAs<ComplexType>()->getElementType(); 3862 if (S.Context.hasSameType(ET, DestTy)) 3863 return CK_IntegralComplexToReal; 3864 Src = S.ImpCastExprToType(Src.take(), ET, CK_IntegralComplexToReal); 3865 return CK_IntegralCast; 3866 } 3867 case Type::STK_Bool: 3868 return CK_IntegralComplexToBoolean; 3869 case Type::STK_Floating: 3870 Src = S.ImpCastExprToType(Src.take(), SrcTy->getAs<ComplexType>()->getElementType(), 3871 CK_IntegralComplexToReal); 3872 return CK_IntegralToFloating; 3873 case Type::STK_Pointer: 3874 llvm_unreachable("valid complex int->pointer cast?"); 3875 case Type::STK_MemberPointer: 3876 llvm_unreachable("member pointer type in C"); 3877 } 3878 break; 3879 } 3880 3881 llvm_unreachable("Unhandled scalar cast"); 3882 return CK_BitCast; 3883} 3884 3885/// CheckCastTypes - Check type constraints for casting between types. 3886ExprResult Sema::CheckCastTypes(SourceLocation CastStartLoc, SourceRange TyR, 3887 QualType castType, Expr *castExpr, 3888 CastKind& Kind, ExprValueKind &VK, 3889 CXXCastPath &BasePath, bool FunctionalStyle) { 3890 if (castExpr->getType() == Context.UnknownAnyTy) 3891 return checkUnknownAnyCast(TyR, castType, castExpr, Kind, VK, BasePath); 3892 3893 if (getLangOptions().CPlusPlus) 3894 return CXXCheckCStyleCast(SourceRange(CastStartLoc, 3895 castExpr->getLocEnd()), 3896 castType, VK, castExpr, Kind, BasePath, 3897 FunctionalStyle); 3898 3899 assert(!castExpr->getType()->isPlaceholderType()); 3900 3901 // We only support r-value casts in C. 3902 VK = VK_RValue; 3903 3904 // C99 6.5.4p2: the cast type needs to be void or scalar and the expression 3905 // type needs to be scalar. 3906 if (castType->isVoidType()) { 3907 // We don't necessarily do lvalue-to-rvalue conversions on this. 3908 ExprResult castExprRes = IgnoredValueConversions(castExpr); 3909 if (castExprRes.isInvalid()) 3910 return ExprError(); 3911 castExpr = castExprRes.take(); 3912 3913 // Cast to void allows any expr type. 3914 Kind = CK_ToVoid; 3915 return Owned(castExpr); 3916 } 3917 3918 ExprResult castExprRes = DefaultFunctionArrayLvalueConversion(castExpr); 3919 if (castExprRes.isInvalid()) 3920 return ExprError(); 3921 castExpr = castExprRes.take(); 3922 3923 if (RequireCompleteType(TyR.getBegin(), castType, 3924 diag::err_typecheck_cast_to_incomplete)) 3925 return ExprError(); 3926 3927 if (!castType->isScalarType() && !castType->isVectorType()) { 3928 if (Context.hasSameUnqualifiedType(castType, castExpr->getType()) && 3929 (castType->isStructureType() || castType->isUnionType())) { 3930 // GCC struct/union extension: allow cast to self. 3931 // FIXME: Check that the cast destination type is complete. 3932 Diag(TyR.getBegin(), diag::ext_typecheck_cast_nonscalar) 3933 << castType << castExpr->getSourceRange(); 3934 Kind = CK_NoOp; 3935 return Owned(castExpr); 3936 } 3937 3938 if (castType->isUnionType()) { 3939 // GCC cast to union extension 3940 RecordDecl *RD = castType->getAs<RecordType>()->getDecl(); 3941 RecordDecl::field_iterator Field, FieldEnd; 3942 for (Field = RD->field_begin(), FieldEnd = RD->field_end(); 3943 Field != FieldEnd; ++Field) { 3944 if (Context.hasSameUnqualifiedType(Field->getType(), 3945 castExpr->getType()) && 3946 !Field->isUnnamedBitfield()) { 3947 Diag(TyR.getBegin(), diag::ext_typecheck_cast_to_union) 3948 << castExpr->getSourceRange(); 3949 break; 3950 } 3951 } 3952 if (Field == FieldEnd) { 3953 Diag(TyR.getBegin(), diag::err_typecheck_cast_to_union_no_type) 3954 << castExpr->getType() << castExpr->getSourceRange(); 3955 return ExprError(); 3956 } 3957 Kind = CK_ToUnion; 3958 return Owned(castExpr); 3959 } 3960 3961 // Reject any other conversions to non-scalar types. 3962 Diag(TyR.getBegin(), diag::err_typecheck_cond_expect_scalar) 3963 << castType << castExpr->getSourceRange(); 3964 return ExprError(); 3965 } 3966 3967 // The type we're casting to is known to be a scalar or vector. 3968 3969 // Require the operand to be a scalar or vector. 3970 if (!castExpr->getType()->isScalarType() && 3971 !castExpr->getType()->isVectorType()) { 3972 Diag(castExpr->getLocStart(), 3973 diag::err_typecheck_expect_scalar_operand) 3974 << castExpr->getType() << castExpr->getSourceRange(); 3975 return ExprError(); 3976 } 3977 3978 if (castType->isExtVectorType()) 3979 return CheckExtVectorCast(TyR, castType, castExpr, Kind); 3980 3981 if (castType->isVectorType()) { 3982 if (castType->getAs<VectorType>()->getVectorKind() == 3983 VectorType::AltiVecVector && 3984 (castExpr->getType()->isIntegerType() || 3985 castExpr->getType()->isFloatingType())) { 3986 Kind = CK_VectorSplat; 3987 return Owned(castExpr); 3988 } else if (CheckVectorCast(TyR, castType, castExpr->getType(), Kind)) { 3989 return ExprError(); 3990 } else 3991 return Owned(castExpr); 3992 } 3993 if (castExpr->getType()->isVectorType()) { 3994 if (CheckVectorCast(TyR, castExpr->getType(), castType, Kind)) 3995 return ExprError(); 3996 else 3997 return Owned(castExpr); 3998 } 3999 4000 // The source and target types are both scalars, i.e. 4001 // - arithmetic types (fundamental, enum, and complex) 4002 // - all kinds of pointers 4003 // Note that member pointers were filtered out with C++, above. 4004 4005 if (isa<ObjCSelectorExpr>(castExpr)) { 4006 Diag(castExpr->getLocStart(), diag::err_cast_selector_expr); 4007 return ExprError(); 4008 } 4009 4010 // If either type is a pointer, the other type has to be either an 4011 // integer or a pointer. 4012 QualType castExprType = castExpr->getType(); 4013 if (!castType->isArithmeticType()) { 4014 if (!castExprType->isIntegralType(Context) && 4015 castExprType->isArithmeticType()) { 4016 Diag(castExpr->getLocStart(), 4017 diag::err_cast_pointer_from_non_pointer_int) 4018 << castExprType << castExpr->getSourceRange(); 4019 return ExprError(); 4020 } 4021 } else if (!castExpr->getType()->isArithmeticType()) { 4022 if (!castType->isIntegralType(Context) && castType->isArithmeticType()) { 4023 Diag(castExpr->getLocStart(), diag::err_cast_pointer_to_non_pointer_int) 4024 << castType << castExpr->getSourceRange(); 4025 return ExprError(); 4026 } 4027 } 4028 4029 if (getLangOptions().ObjCAutoRefCount) { 4030 // Diagnose problems with Objective-C casts involving lifetime qualifiers. 4031 CheckObjCARCConversion(SourceRange(CastStartLoc, castExpr->getLocEnd()), 4032 castType, castExpr, CCK_CStyleCast); 4033 4034 if (const PointerType *CastPtr = castType->getAs<PointerType>()) { 4035 if (const PointerType *ExprPtr = castExprType->getAs<PointerType>()) { 4036 Qualifiers CastQuals = CastPtr->getPointeeType().getQualifiers(); 4037 Qualifiers ExprQuals = ExprPtr->getPointeeType().getQualifiers(); 4038 if (CastPtr->getPointeeType()->isObjCLifetimeType() && 4039 ExprPtr->getPointeeType()->isObjCLifetimeType() && 4040 !CastQuals.compatiblyIncludesObjCLifetime(ExprQuals)) { 4041 Diag(castExpr->getLocStart(), 4042 diag::err_typecheck_incompatible_ownership) 4043 << castExprType << castType << AA_Casting 4044 << castExpr->getSourceRange(); 4045 4046 return ExprError(); 4047 } 4048 } 4049 } 4050 else if (!CheckObjCARCUnavailableWeakConversion(castType, castExprType)) { 4051 Diag(castExpr->getLocStart(), 4052 diag::err_arc_convesion_of_weak_unavailable) << 1 4053 << castExprType << castType 4054 << castExpr->getSourceRange(); 4055 return ExprError(); 4056 } 4057 } 4058 4059 castExprRes = Owned(castExpr); 4060 Kind = PrepareScalarCast(*this, castExprRes, castType); 4061 if (castExprRes.isInvalid()) 4062 return ExprError(); 4063 castExpr = castExprRes.take(); 4064 4065 if (Kind == CK_BitCast) 4066 CheckCastAlign(castExpr, castType, TyR); 4067 4068 return Owned(castExpr); 4069} 4070 4071bool Sema::CheckVectorCast(SourceRange R, QualType VectorTy, QualType Ty, 4072 CastKind &Kind) { 4073 assert(VectorTy->isVectorType() && "Not a vector type!"); 4074 4075 if (Ty->isVectorType() || Ty->isIntegerType()) { 4076 if (Context.getTypeSize(VectorTy) != Context.getTypeSize(Ty)) 4077 return Diag(R.getBegin(), 4078 Ty->isVectorType() ? 4079 diag::err_invalid_conversion_between_vectors : 4080 diag::err_invalid_conversion_between_vector_and_integer) 4081 << VectorTy << Ty << R; 4082 } else 4083 return Diag(R.getBegin(), 4084 diag::err_invalid_conversion_between_vector_and_scalar) 4085 << VectorTy << Ty << R; 4086 4087 Kind = CK_BitCast; 4088 return false; 4089} 4090 4091ExprResult Sema::CheckExtVectorCast(SourceRange R, QualType DestTy, 4092 Expr *CastExpr, CastKind &Kind) { 4093 assert(DestTy->isExtVectorType() && "Not an extended vector type!"); 4094 4095 QualType SrcTy = CastExpr->getType(); 4096 4097 // If SrcTy is a VectorType, the total size must match to explicitly cast to 4098 // an ExtVectorType. 4099 if (SrcTy->isVectorType()) { 4100 if (Context.getTypeSize(DestTy) != Context.getTypeSize(SrcTy)) { 4101 Diag(R.getBegin(),diag::err_invalid_conversion_between_ext_vectors) 4102 << DestTy << SrcTy << R; 4103 return ExprError(); 4104 } 4105 Kind = CK_BitCast; 4106 return Owned(CastExpr); 4107 } 4108 4109 // All non-pointer scalars can be cast to ExtVector type. The appropriate 4110 // conversion will take place first from scalar to elt type, and then 4111 // splat from elt type to vector. 4112 if (SrcTy->isPointerType()) 4113 return Diag(R.getBegin(), 4114 diag::err_invalid_conversion_between_vector_and_scalar) 4115 << DestTy << SrcTy << R; 4116 4117 QualType DestElemTy = DestTy->getAs<ExtVectorType>()->getElementType(); 4118 ExprResult CastExprRes = Owned(CastExpr); 4119 CastKind CK = PrepareScalarCast(*this, CastExprRes, DestElemTy); 4120 if (CastExprRes.isInvalid()) 4121 return ExprError(); 4122 CastExpr = ImpCastExprToType(CastExprRes.take(), DestElemTy, CK).take(); 4123 4124 Kind = CK_VectorSplat; 4125 return Owned(CastExpr); 4126} 4127 4128ExprResult 4129Sema::ActOnCastExpr(Scope *S, SourceLocation LParenLoc, 4130 Declarator &D, ParsedType &Ty, 4131 SourceLocation RParenLoc, Expr *castExpr) { 4132 assert(!D.isInvalidType() && (castExpr != 0) && 4133 "ActOnCastExpr(): missing type or expr"); 4134 4135 TypeSourceInfo *castTInfo = GetTypeForDeclaratorCast(D, castExpr->getType()); 4136 if (D.isInvalidType()) 4137 return ExprError(); 4138 4139 if (getLangOptions().CPlusPlus) { 4140 // Check that there are no default arguments (C++ only). 4141 CheckExtraCXXDefaultArguments(D); 4142 } 4143 4144 QualType castType = castTInfo->getType(); 4145 Ty = CreateParsedType(castType, castTInfo); 4146 4147 bool isVectorLiteral = false; 4148 4149 // Check for an altivec or OpenCL literal, 4150 // i.e. all the elements are integer constants. 4151 ParenExpr *PE = dyn_cast<ParenExpr>(castExpr); 4152 ParenListExpr *PLE = dyn_cast<ParenListExpr>(castExpr); 4153 if (getLangOptions().AltiVec && castType->isVectorType() && (PE || PLE)) { 4154 if (PLE && PLE->getNumExprs() == 0) { 4155 Diag(PLE->getExprLoc(), diag::err_altivec_empty_initializer); 4156 return ExprError(); 4157 } 4158 if (PE || PLE->getNumExprs() == 1) { 4159 Expr *E = (PE ? PE->getSubExpr() : PLE->getExpr(0)); 4160 if (!E->getType()->isVectorType()) 4161 isVectorLiteral = true; 4162 } 4163 else 4164 isVectorLiteral = true; 4165 } 4166 4167 // If this is a vector initializer, '(' type ')' '(' init, ..., init ')' 4168 // then handle it as such. 4169 if (isVectorLiteral) 4170 return BuildVectorLiteral(LParenLoc, RParenLoc, castExpr, castTInfo); 4171 4172 // If the Expr being casted is a ParenListExpr, handle it specially. 4173 // This is not an AltiVec-style cast, so turn the ParenListExpr into a 4174 // sequence of BinOp comma operators. 4175 if (isa<ParenListExpr>(castExpr)) { 4176 ExprResult Result = MaybeConvertParenListExprToParenExpr(S, castExpr); 4177 if (Result.isInvalid()) return ExprError(); 4178 castExpr = Result.take(); 4179 } 4180 4181 return BuildCStyleCastExpr(LParenLoc, castTInfo, RParenLoc, castExpr); 4182} 4183 4184ExprResult 4185Sema::BuildCStyleCastExpr(SourceLocation LParenLoc, TypeSourceInfo *Ty, 4186 SourceLocation RParenLoc, Expr *castExpr) { 4187 CastKind Kind = CK_Invalid; 4188 ExprValueKind VK = VK_RValue; 4189 CXXCastPath BasePath; 4190 ExprResult CastResult = 4191 CheckCastTypes(LParenLoc, SourceRange(LParenLoc, RParenLoc), Ty->getType(), 4192 castExpr, Kind, VK, BasePath); 4193 if (CastResult.isInvalid()) 4194 return ExprError(); 4195 castExpr = CastResult.take(); 4196 4197 return Owned(CStyleCastExpr::Create(Context, 4198 Ty->getType().getNonLValueExprType(Context), 4199 VK, Kind, castExpr, &BasePath, Ty, 4200 LParenLoc, RParenLoc)); 4201} 4202 4203ExprResult Sema::BuildVectorLiteral(SourceLocation LParenLoc, 4204 SourceLocation RParenLoc, Expr *E, 4205 TypeSourceInfo *TInfo) { 4206 assert((isa<ParenListExpr>(E) || isa<ParenExpr>(E)) && 4207 "Expected paren or paren list expression"); 4208 4209 Expr **exprs; 4210 unsigned numExprs; 4211 Expr *subExpr; 4212 if (ParenListExpr *PE = dyn_cast<ParenListExpr>(E)) { 4213 exprs = PE->getExprs(); 4214 numExprs = PE->getNumExprs(); 4215 } else { 4216 subExpr = cast<ParenExpr>(E)->getSubExpr(); 4217 exprs = &subExpr; 4218 numExprs = 1; 4219 } 4220 4221 QualType Ty = TInfo->getType(); 4222 assert(Ty->isVectorType() && "Expected vector type"); 4223 4224 llvm::SmallVector<Expr *, 8> initExprs; 4225 // '(...)' form of vector initialization in AltiVec: the number of 4226 // initializers must be one or must match the size of the vector. 4227 // If a single value is specified in the initializer then it will be 4228 // replicated to all the components of the vector 4229 if (Ty->getAs<VectorType>()->getVectorKind() == 4230 VectorType::AltiVecVector) { 4231 unsigned numElems = Ty->getAs<VectorType>()->getNumElements(); 4232 // The number of initializers must be one or must match the size of the 4233 // vector. If a single value is specified in the initializer then it will 4234 // be replicated to all the components of the vector 4235 if (numExprs == 1) { 4236 QualType ElemTy = Ty->getAs<VectorType>()->getElementType(); 4237 ExprResult Literal = Owned(exprs[0]); 4238 Literal = ImpCastExprToType(Literal.take(), ElemTy, 4239 PrepareScalarCast(*this, Literal, ElemTy)); 4240 return BuildCStyleCastExpr(LParenLoc, TInfo, RParenLoc, Literal.take()); 4241 } 4242 else if (numExprs < numElems) { 4243 Diag(E->getExprLoc(), 4244 diag::err_incorrect_number_of_vector_initializers); 4245 return ExprError(); 4246 } 4247 else 4248 for (unsigned i = 0, e = numExprs; i != e; ++i) 4249 initExprs.push_back(exprs[i]); 4250 } 4251 else 4252 for (unsigned i = 0, e = numExprs; i != e; ++i) 4253 initExprs.push_back(exprs[i]); 4254 4255 // FIXME: This means that pretty-printing the final AST will produce curly 4256 // braces instead of the original commas. 4257 InitListExpr *initE = new (Context) InitListExpr(Context, LParenLoc, 4258 &initExprs[0], 4259 initExprs.size(), RParenLoc); 4260 initE->setType(Ty); 4261 return BuildCompoundLiteralExpr(LParenLoc, TInfo, RParenLoc, initE); 4262} 4263 4264/// This is not an AltiVec-style cast, so turn the ParenListExpr into a sequence 4265/// of comma binary operators. 4266ExprResult 4267Sema::MaybeConvertParenListExprToParenExpr(Scope *S, Expr *expr) { 4268 ParenListExpr *E = dyn_cast<ParenListExpr>(expr); 4269 if (!E) 4270 return Owned(expr); 4271 4272 ExprResult Result(E->getExpr(0)); 4273 4274 for (unsigned i = 1, e = E->getNumExprs(); i != e && !Result.isInvalid(); ++i) 4275 Result = ActOnBinOp(S, E->getExprLoc(), tok::comma, Result.get(), 4276 E->getExpr(i)); 4277 4278 if (Result.isInvalid()) return ExprError(); 4279 4280 return ActOnParenExpr(E->getLParenLoc(), E->getRParenLoc(), Result.get()); 4281} 4282 4283ExprResult Sema::ActOnParenOrParenListExpr(SourceLocation L, 4284 SourceLocation R, 4285 MultiExprArg Val) { 4286 unsigned nexprs = Val.size(); 4287 Expr **exprs = reinterpret_cast<Expr**>(Val.release()); 4288 assert((exprs != 0) && "ActOnParenOrParenListExpr() missing expr list"); 4289 Expr *expr; 4290 if (nexprs == 1) 4291 expr = new (Context) ParenExpr(L, R, exprs[0]); 4292 else 4293 expr = new (Context) ParenListExpr(Context, L, exprs, nexprs, R, 4294 exprs[nexprs-1]->getType()); 4295 return Owned(expr); 4296} 4297 4298/// \brief Emit a specialized diagnostic when one expression is a null pointer 4299/// constant and the other is not a pointer. 4300bool Sema::DiagnoseConditionalForNull(Expr *LHS, Expr *RHS, 4301 SourceLocation QuestionLoc) { 4302 Expr *NullExpr = LHS; 4303 Expr *NonPointerExpr = RHS; 4304 Expr::NullPointerConstantKind NullKind = 4305 NullExpr->isNullPointerConstant(Context, 4306 Expr::NPC_ValueDependentIsNotNull); 4307 4308 if (NullKind == Expr::NPCK_NotNull) { 4309 NullExpr = RHS; 4310 NonPointerExpr = LHS; 4311 NullKind = 4312 NullExpr->isNullPointerConstant(Context, 4313 Expr::NPC_ValueDependentIsNotNull); 4314 } 4315 4316 if (NullKind == Expr::NPCK_NotNull) 4317 return false; 4318 4319 if (NullKind == Expr::NPCK_ZeroInteger) { 4320 // In this case, check to make sure that we got here from a "NULL" 4321 // string in the source code. 4322 NullExpr = NullExpr->IgnoreParenImpCasts(); 4323 SourceLocation loc = NullExpr->getExprLoc(); 4324 if (!findMacroSpelling(loc, "NULL")) 4325 return false; 4326 } 4327 4328 int DiagType = (NullKind == Expr::NPCK_CXX0X_nullptr); 4329 Diag(QuestionLoc, diag::err_typecheck_cond_incompatible_operands_null) 4330 << NonPointerExpr->getType() << DiagType 4331 << NonPointerExpr->getSourceRange(); 4332 return true; 4333} 4334 4335/// Note that lhs is not null here, even if this is the gnu "x ?: y" extension. 4336/// In that case, lhs = cond. 4337/// C99 6.5.15 4338QualType Sema::CheckConditionalOperands(ExprResult &Cond, ExprResult &LHS, ExprResult &RHS, 4339 ExprValueKind &VK, ExprObjectKind &OK, 4340 SourceLocation QuestionLoc) { 4341 4342 ExprResult lhsResult = CheckPlaceholderExpr(LHS.get()); 4343 if (!lhsResult.isUsable()) return QualType(); 4344 LHS = move(lhsResult); 4345 4346 ExprResult rhsResult = CheckPlaceholderExpr(RHS.get()); 4347 if (!rhsResult.isUsable()) return QualType(); 4348 RHS = move(rhsResult); 4349 4350 // C++ is sufficiently different to merit its own checker. 4351 if (getLangOptions().CPlusPlus) 4352 return CXXCheckConditionalOperands(Cond, LHS, RHS, VK, OK, QuestionLoc); 4353 4354 VK = VK_RValue; 4355 OK = OK_Ordinary; 4356 4357 Cond = UsualUnaryConversions(Cond.take()); 4358 if (Cond.isInvalid()) 4359 return QualType(); 4360 LHS = UsualUnaryConversions(LHS.take()); 4361 if (LHS.isInvalid()) 4362 return QualType(); 4363 RHS = UsualUnaryConversions(RHS.take()); 4364 if (RHS.isInvalid()) 4365 return QualType(); 4366 4367 QualType CondTy = Cond.get()->getType(); 4368 QualType LHSTy = LHS.get()->getType(); 4369 QualType RHSTy = RHS.get()->getType(); 4370 4371 // first, check the condition. 4372 if (!CondTy->isScalarType()) { // C99 6.5.15p2 4373 // OpenCL: Sec 6.3.i says the condition is allowed to be a vector or scalar. 4374 // Throw an error if its not either. 4375 if (getLangOptions().OpenCL) { 4376 if (!CondTy->isVectorType()) { 4377 Diag(Cond.get()->getLocStart(), 4378 diag::err_typecheck_cond_expect_scalar_or_vector) 4379 << CondTy; 4380 return QualType(); 4381 } 4382 } 4383 else { 4384 Diag(Cond.get()->getLocStart(), diag::err_typecheck_cond_expect_scalar) 4385 << CondTy; 4386 return QualType(); 4387 } 4388 } 4389 4390 // Now check the two expressions. 4391 if (LHSTy->isVectorType() || RHSTy->isVectorType()) 4392 return CheckVectorOperands(LHS, RHS, QuestionLoc, /*isCompAssign*/false); 4393 4394 // OpenCL: If the condition is a vector, and both operands are scalar, 4395 // attempt to implicity convert them to the vector type to act like the 4396 // built in select. 4397 if (getLangOptions().OpenCL && CondTy->isVectorType()) { 4398 // Both operands should be of scalar type. 4399 if (!LHSTy->isScalarType()) { 4400 Diag(LHS.get()->getLocStart(), diag::err_typecheck_cond_expect_scalar) 4401 << CondTy; 4402 return QualType(); 4403 } 4404 if (!RHSTy->isScalarType()) { 4405 Diag(RHS.get()->getLocStart(), diag::err_typecheck_cond_expect_scalar) 4406 << CondTy; 4407 return QualType(); 4408 } 4409 // Implicity convert these scalars to the type of the condition. 4410 LHS = ImpCastExprToType(LHS.take(), CondTy, CK_IntegralCast); 4411 RHS = ImpCastExprToType(RHS.take(), CondTy, CK_IntegralCast); 4412 } 4413 4414 // If both operands have arithmetic type, do the usual arithmetic conversions 4415 // to find a common type: C99 6.5.15p3,5. 4416 if (LHSTy->isArithmeticType() && RHSTy->isArithmeticType()) { 4417 UsualArithmeticConversions(LHS, RHS); 4418 if (LHS.isInvalid() || RHS.isInvalid()) 4419 return QualType(); 4420 return LHS.get()->getType(); 4421 } 4422 4423 // If both operands are the same structure or union type, the result is that 4424 // type. 4425 if (const RecordType *LHSRT = LHSTy->getAs<RecordType>()) { // C99 6.5.15p3 4426 if (const RecordType *RHSRT = RHSTy->getAs<RecordType>()) 4427 if (LHSRT->getDecl() == RHSRT->getDecl()) 4428 // "If both the operands have structure or union type, the result has 4429 // that type." This implies that CV qualifiers are dropped. 4430 return LHSTy.getUnqualifiedType(); 4431 // FIXME: Type of conditional expression must be complete in C mode. 4432 } 4433 4434 // C99 6.5.15p5: "If both operands have void type, the result has void type." 4435 // The following || allows only one side to be void (a GCC-ism). 4436 if (LHSTy->isVoidType() || RHSTy->isVoidType()) { 4437 if (!LHSTy->isVoidType()) 4438 Diag(RHS.get()->getLocStart(), diag::ext_typecheck_cond_one_void) 4439 << RHS.get()->getSourceRange(); 4440 if (!RHSTy->isVoidType()) 4441 Diag(LHS.get()->getLocStart(), diag::ext_typecheck_cond_one_void) 4442 << LHS.get()->getSourceRange(); 4443 LHS = ImpCastExprToType(LHS.take(), Context.VoidTy, CK_ToVoid); 4444 RHS = ImpCastExprToType(RHS.take(), Context.VoidTy, CK_ToVoid); 4445 return Context.VoidTy; 4446 } 4447 // C99 6.5.15p6 - "if one operand is a null pointer constant, the result has 4448 // the type of the other operand." 4449 if ((LHSTy->isAnyPointerType() || LHSTy->isBlockPointerType()) && 4450 RHS.get()->isNullPointerConstant(Context, Expr::NPC_ValueDependentIsNull)) { 4451 // promote the null to a pointer. 4452 RHS = ImpCastExprToType(RHS.take(), LHSTy, CK_NullToPointer); 4453 return LHSTy; 4454 } 4455 if ((RHSTy->isAnyPointerType() || RHSTy->isBlockPointerType()) && 4456 LHS.get()->isNullPointerConstant(Context, Expr::NPC_ValueDependentIsNull)) { 4457 LHS = ImpCastExprToType(LHS.take(), RHSTy, CK_NullToPointer); 4458 return RHSTy; 4459 } 4460 4461 // All objective-c pointer type analysis is done here. 4462 QualType compositeType = FindCompositeObjCPointerType(LHS, RHS, 4463 QuestionLoc); 4464 if (LHS.isInvalid() || RHS.isInvalid()) 4465 return QualType(); 4466 if (!compositeType.isNull()) 4467 return compositeType; 4468 4469 4470 // Handle block pointer types. 4471 if (LHSTy->isBlockPointerType() || RHSTy->isBlockPointerType()) { 4472 if (!LHSTy->isBlockPointerType() || !RHSTy->isBlockPointerType()) { 4473 if (LHSTy->isVoidPointerType() || RHSTy->isVoidPointerType()) { 4474 QualType destType = Context.getPointerType(Context.VoidTy); 4475 LHS = ImpCastExprToType(LHS.take(), destType, CK_BitCast); 4476 RHS = ImpCastExprToType(RHS.take(), destType, CK_BitCast); 4477 return destType; 4478 } 4479 Diag(QuestionLoc, diag::err_typecheck_cond_incompatible_operands) 4480 << LHSTy << RHSTy << LHS.get()->getSourceRange() << RHS.get()->getSourceRange(); 4481 return QualType(); 4482 } 4483 // We have 2 block pointer types. 4484 if (Context.getCanonicalType(LHSTy) == Context.getCanonicalType(RHSTy)) { 4485 // Two identical block pointer types are always compatible. 4486 return LHSTy; 4487 } 4488 // The block pointer types aren't identical, continue checking. 4489 QualType lhptee = LHSTy->getAs<BlockPointerType>()->getPointeeType(); 4490 QualType rhptee = RHSTy->getAs<BlockPointerType>()->getPointeeType(); 4491 4492 if (!Context.typesAreCompatible(lhptee.getUnqualifiedType(), 4493 rhptee.getUnqualifiedType())) { 4494 Diag(QuestionLoc, diag::warn_typecheck_cond_incompatible_pointers) 4495 << LHSTy << RHSTy << LHS.get()->getSourceRange() << RHS.get()->getSourceRange(); 4496 // In this situation, we assume void* type. No especially good 4497 // reason, but this is what gcc does, and we do have to pick 4498 // to get a consistent AST. 4499 QualType incompatTy = Context.getPointerType(Context.VoidTy); 4500 LHS = ImpCastExprToType(LHS.take(), incompatTy, CK_BitCast); 4501 RHS = ImpCastExprToType(RHS.take(), incompatTy, CK_BitCast); 4502 return incompatTy; 4503 } 4504 // The block pointer types are compatible. 4505 LHS = ImpCastExprToType(LHS.take(), LHSTy, CK_BitCast); 4506 RHS = ImpCastExprToType(RHS.take(), LHSTy, CK_BitCast); 4507 return LHSTy; 4508 } 4509 4510 // Check constraints for C object pointers types (C99 6.5.15p3,6). 4511 if (LHSTy->isPointerType() && RHSTy->isPointerType()) { 4512 // get the "pointed to" types 4513 QualType lhptee = LHSTy->getAs<PointerType>()->getPointeeType(); 4514 QualType rhptee = RHSTy->getAs<PointerType>()->getPointeeType(); 4515 4516 // ignore qualifiers on void (C99 6.5.15p3, clause 6) 4517 if (lhptee->isVoidType() && rhptee->isIncompleteOrObjectType()) { 4518 // Figure out necessary qualifiers (C99 6.5.15p6) 4519 QualType destPointee 4520 = Context.getQualifiedType(lhptee, rhptee.getQualifiers()); 4521 QualType destType = Context.getPointerType(destPointee); 4522 // Add qualifiers if necessary. 4523 LHS = ImpCastExprToType(LHS.take(), destType, CK_NoOp); 4524 // Promote to void*. 4525 RHS = ImpCastExprToType(RHS.take(), destType, CK_BitCast); 4526 return destType; 4527 } 4528 if (rhptee->isVoidType() && lhptee->isIncompleteOrObjectType()) { 4529 QualType destPointee 4530 = Context.getQualifiedType(rhptee, lhptee.getQualifiers()); 4531 QualType destType = Context.getPointerType(destPointee); 4532 // Add qualifiers if necessary. 4533 RHS = ImpCastExprToType(RHS.take(), destType, CK_NoOp); 4534 // Promote to void*. 4535 LHS = ImpCastExprToType(LHS.take(), destType, CK_BitCast); 4536 return destType; 4537 } 4538 4539 if (Context.getCanonicalType(LHSTy) == Context.getCanonicalType(RHSTy)) { 4540 // Two identical pointer types are always compatible. 4541 return LHSTy; 4542 } 4543 if (!Context.typesAreCompatible(lhptee.getUnqualifiedType(), 4544 rhptee.getUnqualifiedType())) { 4545 Diag(QuestionLoc, diag::warn_typecheck_cond_incompatible_pointers) 4546 << LHSTy << RHSTy << LHS.get()->getSourceRange() << RHS.get()->getSourceRange(); 4547 // In this situation, we assume void* type. No especially good 4548 // reason, but this is what gcc does, and we do have to pick 4549 // to get a consistent AST. 4550 QualType incompatTy = Context.getPointerType(Context.VoidTy); 4551 LHS = ImpCastExprToType(LHS.take(), incompatTy, CK_BitCast); 4552 RHS = ImpCastExprToType(RHS.take(), incompatTy, CK_BitCast); 4553 return incompatTy; 4554 } 4555 // The pointer types are compatible. 4556 // C99 6.5.15p6: If both operands are pointers to compatible types *or* to 4557 // differently qualified versions of compatible types, the result type is 4558 // a pointer to an appropriately qualified version of the *composite* 4559 // type. 4560 // FIXME: Need to calculate the composite type. 4561 // FIXME: Need to add qualifiers 4562 LHS = ImpCastExprToType(LHS.take(), LHSTy, CK_BitCast); 4563 RHS = ImpCastExprToType(RHS.take(), LHSTy, CK_BitCast); 4564 return LHSTy; 4565 } 4566 4567 // GCC compatibility: soften pointer/integer mismatch. Note that 4568 // null pointers have been filtered out by this point. 4569 if (RHSTy->isPointerType() && LHSTy->isIntegerType()) { 4570 Diag(QuestionLoc, diag::warn_typecheck_cond_pointer_integer_mismatch) 4571 << LHSTy << RHSTy << LHS.get()->getSourceRange() << RHS.get()->getSourceRange(); 4572 LHS = ImpCastExprToType(LHS.take(), RHSTy, CK_IntegralToPointer); 4573 return RHSTy; 4574 } 4575 if (LHSTy->isPointerType() && RHSTy->isIntegerType()) { 4576 Diag(QuestionLoc, diag::warn_typecheck_cond_pointer_integer_mismatch) 4577 << LHSTy << RHSTy << LHS.get()->getSourceRange() << RHS.get()->getSourceRange(); 4578 RHS = ImpCastExprToType(RHS.take(), LHSTy, CK_IntegralToPointer); 4579 return LHSTy; 4580 } 4581 4582 // Emit a better diagnostic if one of the expressions is a null pointer 4583 // constant and the other is not a pointer type. In this case, the user most 4584 // likely forgot to take the address of the other expression. 4585 if (DiagnoseConditionalForNull(LHS.get(), RHS.get(), QuestionLoc)) 4586 return QualType(); 4587 4588 // Otherwise, the operands are not compatible. 4589 Diag(QuestionLoc, diag::err_typecheck_cond_incompatible_operands) 4590 << LHSTy << RHSTy << LHS.get()->getSourceRange() << RHS.get()->getSourceRange(); 4591 return QualType(); 4592} 4593 4594/// FindCompositeObjCPointerType - Helper method to find composite type of 4595/// two objective-c pointer types of the two input expressions. 4596QualType Sema::FindCompositeObjCPointerType(ExprResult &LHS, ExprResult &RHS, 4597 SourceLocation QuestionLoc) { 4598 QualType LHSTy = LHS.get()->getType(); 4599 QualType RHSTy = RHS.get()->getType(); 4600 4601 // Handle things like Class and struct objc_class*. Here we case the result 4602 // to the pseudo-builtin, because that will be implicitly cast back to the 4603 // redefinition type if an attempt is made to access its fields. 4604 if (LHSTy->isObjCClassType() && 4605 (Context.hasSameType(RHSTy, Context.ObjCClassRedefinitionType))) { 4606 RHS = ImpCastExprToType(RHS.take(), LHSTy, CK_BitCast); 4607 return LHSTy; 4608 } 4609 if (RHSTy->isObjCClassType() && 4610 (Context.hasSameType(LHSTy, Context.ObjCClassRedefinitionType))) { 4611 LHS = ImpCastExprToType(LHS.take(), RHSTy, CK_BitCast); 4612 return RHSTy; 4613 } 4614 // And the same for struct objc_object* / id 4615 if (LHSTy->isObjCIdType() && 4616 (Context.hasSameType(RHSTy, Context.ObjCIdRedefinitionType))) { 4617 RHS = ImpCastExprToType(RHS.take(), LHSTy, CK_BitCast); 4618 return LHSTy; 4619 } 4620 if (RHSTy->isObjCIdType() && 4621 (Context.hasSameType(LHSTy, Context.ObjCIdRedefinitionType))) { 4622 LHS = ImpCastExprToType(LHS.take(), RHSTy, CK_BitCast); 4623 return RHSTy; 4624 } 4625 // And the same for struct objc_selector* / SEL 4626 if (Context.isObjCSelType(LHSTy) && 4627 (Context.hasSameType(RHSTy, Context.ObjCSelRedefinitionType))) { 4628 RHS = ImpCastExprToType(RHS.take(), LHSTy, CK_BitCast); 4629 return LHSTy; 4630 } 4631 if (Context.isObjCSelType(RHSTy) && 4632 (Context.hasSameType(LHSTy, Context.ObjCSelRedefinitionType))) { 4633 LHS = ImpCastExprToType(LHS.take(), RHSTy, CK_BitCast); 4634 return RHSTy; 4635 } 4636 // Check constraints for Objective-C object pointers types. 4637 if (LHSTy->isObjCObjectPointerType() && RHSTy->isObjCObjectPointerType()) { 4638 4639 if (Context.getCanonicalType(LHSTy) == Context.getCanonicalType(RHSTy)) { 4640 // Two identical object pointer types are always compatible. 4641 return LHSTy; 4642 } 4643 const ObjCObjectPointerType *LHSOPT = LHSTy->getAs<ObjCObjectPointerType>(); 4644 const ObjCObjectPointerType *RHSOPT = RHSTy->getAs<ObjCObjectPointerType>(); 4645 QualType compositeType = LHSTy; 4646 4647 // If both operands are interfaces and either operand can be 4648 // assigned to the other, use that type as the composite 4649 // type. This allows 4650 // xxx ? (A*) a : (B*) b 4651 // where B is a subclass of A. 4652 // 4653 // Additionally, as for assignment, if either type is 'id' 4654 // allow silent coercion. Finally, if the types are 4655 // incompatible then make sure to use 'id' as the composite 4656 // type so the result is acceptable for sending messages to. 4657 4658 // FIXME: Consider unifying with 'areComparableObjCPointerTypes'. 4659 // It could return the composite type. 4660 if (Context.canAssignObjCInterfaces(LHSOPT, RHSOPT)) { 4661 compositeType = RHSOPT->isObjCBuiltinType() ? RHSTy : LHSTy; 4662 } else if (Context.canAssignObjCInterfaces(RHSOPT, LHSOPT)) { 4663 compositeType = LHSOPT->isObjCBuiltinType() ? LHSTy : RHSTy; 4664 } else if ((LHSTy->isObjCQualifiedIdType() || 4665 RHSTy->isObjCQualifiedIdType()) && 4666 Context.ObjCQualifiedIdTypesAreCompatible(LHSTy, RHSTy, true)) { 4667 // Need to handle "id<xx>" explicitly. 4668 // GCC allows qualified id and any Objective-C type to devolve to 4669 // id. Currently localizing to here until clear this should be 4670 // part of ObjCQualifiedIdTypesAreCompatible. 4671 compositeType = Context.getObjCIdType(); 4672 } else if (LHSTy->isObjCIdType() || RHSTy->isObjCIdType()) { 4673 compositeType = Context.getObjCIdType(); 4674 } else if (!(compositeType = 4675 Context.areCommonBaseCompatible(LHSOPT, RHSOPT)).isNull()) 4676 ; 4677 else { 4678 Diag(QuestionLoc, diag::ext_typecheck_cond_incompatible_operands) 4679 << LHSTy << RHSTy 4680 << LHS.get()->getSourceRange() << RHS.get()->getSourceRange(); 4681 QualType incompatTy = Context.getObjCIdType(); 4682 LHS = ImpCastExprToType(LHS.take(), incompatTy, CK_BitCast); 4683 RHS = ImpCastExprToType(RHS.take(), incompatTy, CK_BitCast); 4684 return incompatTy; 4685 } 4686 // The object pointer types are compatible. 4687 LHS = ImpCastExprToType(LHS.take(), compositeType, CK_BitCast); 4688 RHS = ImpCastExprToType(RHS.take(), compositeType, CK_BitCast); 4689 return compositeType; 4690 } 4691 // Check Objective-C object pointer types and 'void *' 4692 if (LHSTy->isVoidPointerType() && RHSTy->isObjCObjectPointerType()) { 4693 QualType lhptee = LHSTy->getAs<PointerType>()->getPointeeType(); 4694 QualType rhptee = RHSTy->getAs<ObjCObjectPointerType>()->getPointeeType(); 4695 QualType destPointee 4696 = Context.getQualifiedType(lhptee, rhptee.getQualifiers()); 4697 QualType destType = Context.getPointerType(destPointee); 4698 // Add qualifiers if necessary. 4699 LHS = ImpCastExprToType(LHS.take(), destType, CK_NoOp); 4700 // Promote to void*. 4701 RHS = ImpCastExprToType(RHS.take(), destType, CK_BitCast); 4702 return destType; 4703 } 4704 if (LHSTy->isObjCObjectPointerType() && RHSTy->isVoidPointerType()) { 4705 QualType lhptee = LHSTy->getAs<ObjCObjectPointerType>()->getPointeeType(); 4706 QualType rhptee = RHSTy->getAs<PointerType>()->getPointeeType(); 4707 QualType destPointee 4708 = Context.getQualifiedType(rhptee, lhptee.getQualifiers()); 4709 QualType destType = Context.getPointerType(destPointee); 4710 // Add qualifiers if necessary. 4711 RHS = ImpCastExprToType(RHS.take(), destType, CK_NoOp); 4712 // Promote to void*. 4713 LHS = ImpCastExprToType(LHS.take(), destType, CK_BitCast); 4714 return destType; 4715 } 4716 return QualType(); 4717} 4718 4719/// SuggestParentheses - Emit a note with a fixit hint that wraps 4720/// ParenRange in parentheses. 4721static void SuggestParentheses(Sema &Self, SourceLocation Loc, 4722 const PartialDiagnostic &Note, 4723 SourceRange ParenRange) { 4724 SourceLocation EndLoc = Self.PP.getLocForEndOfToken(ParenRange.getEnd()); 4725 if (ParenRange.getBegin().isFileID() && ParenRange.getEnd().isFileID() && 4726 EndLoc.isValid()) { 4727 Self.Diag(Loc, Note) 4728 << FixItHint::CreateInsertion(ParenRange.getBegin(), "(") 4729 << FixItHint::CreateInsertion(EndLoc, ")"); 4730 } else { 4731 // We can't display the parentheses, so just show the bare note. 4732 Self.Diag(Loc, Note) << ParenRange; 4733 } 4734} 4735 4736static bool IsArithmeticOp(BinaryOperatorKind Opc) { 4737 return Opc >= BO_Mul && Opc <= BO_Shr; 4738} 4739 4740/// IsArithmeticBinaryExpr - Returns true if E is an arithmetic binary 4741/// expression, either using a built-in or overloaded operator, 4742/// and sets *OpCode to the opcode and *RHS to the right-hand side expression. 4743static bool IsArithmeticBinaryExpr(Expr *E, BinaryOperatorKind *Opcode, 4744 Expr **RHS) { 4745 E = E->IgnoreParenImpCasts(); 4746 E = E->IgnoreConversionOperator(); 4747 E = E->IgnoreParenImpCasts(); 4748 4749 // Built-in binary operator. 4750 if (BinaryOperator *OP = dyn_cast<BinaryOperator>(E)) { 4751 if (IsArithmeticOp(OP->getOpcode())) { 4752 *Opcode = OP->getOpcode(); 4753 *RHS = OP->getRHS(); 4754 return true; 4755 } 4756 } 4757 4758 // Overloaded operator. 4759 if (CXXOperatorCallExpr *Call = dyn_cast<CXXOperatorCallExpr>(E)) { 4760 if (Call->getNumArgs() != 2) 4761 return false; 4762 4763 // Make sure this is really a binary operator that is safe to pass into 4764 // BinaryOperator::getOverloadedOpcode(), e.g. it's not a subscript op. 4765 OverloadedOperatorKind OO = Call->getOperator(); 4766 if (OO < OO_Plus || OO > OO_Arrow) 4767 return false; 4768 4769 BinaryOperatorKind OpKind = BinaryOperator::getOverloadedOpcode(OO); 4770 if (IsArithmeticOp(OpKind)) { 4771 *Opcode = OpKind; 4772 *RHS = Call->getArg(1); 4773 return true; 4774 } 4775 } 4776 4777 return false; 4778} 4779 4780static bool IsLogicOp(BinaryOperatorKind Opc) { 4781 return (Opc >= BO_LT && Opc <= BO_NE) || (Opc >= BO_LAnd && Opc <= BO_LOr); 4782} 4783 4784/// ExprLooksBoolean - Returns true if E looks boolean, i.e. it has boolean type 4785/// or is a logical expression such as (x==y) which has int type, but is 4786/// commonly interpreted as boolean. 4787static bool ExprLooksBoolean(Expr *E) { 4788 E = E->IgnoreParenImpCasts(); 4789 4790 if (E->getType()->isBooleanType()) 4791 return true; 4792 if (BinaryOperator *OP = dyn_cast<BinaryOperator>(E)) 4793 return IsLogicOp(OP->getOpcode()); 4794 if (UnaryOperator *OP = dyn_cast<UnaryOperator>(E)) 4795 return OP->getOpcode() == UO_LNot; 4796 4797 return false; 4798} 4799 4800/// DiagnoseConditionalPrecedence - Emit a warning when a conditional operator 4801/// and binary operator are mixed in a way that suggests the programmer assumed 4802/// the conditional operator has higher precedence, for example: 4803/// "int x = a + someBinaryCondition ? 1 : 2". 4804static void DiagnoseConditionalPrecedence(Sema &Self, 4805 SourceLocation OpLoc, 4806 Expr *Condition, 4807 Expr *LHS, 4808 Expr *RHS) { 4809 BinaryOperatorKind CondOpcode; 4810 Expr *CondRHS; 4811 4812 if (!IsArithmeticBinaryExpr(Condition, &CondOpcode, &CondRHS)) 4813 return; 4814 if (!ExprLooksBoolean(CondRHS)) 4815 return; 4816 4817 // The condition is an arithmetic binary expression, with a right- 4818 // hand side that looks boolean, so warn. 4819 4820 Self.Diag(OpLoc, diag::warn_precedence_conditional) 4821 << Condition->getSourceRange() 4822 << BinaryOperator::getOpcodeStr(CondOpcode); 4823 4824 SuggestParentheses(Self, OpLoc, 4825 Self.PDiag(diag::note_precedence_conditional_silence) 4826 << BinaryOperator::getOpcodeStr(CondOpcode), 4827 SourceRange(Condition->getLocStart(), Condition->getLocEnd())); 4828 4829 SuggestParentheses(Self, OpLoc, 4830 Self.PDiag(diag::note_precedence_conditional_first), 4831 SourceRange(CondRHS->getLocStart(), RHS->getLocEnd())); 4832} 4833 4834/// ActOnConditionalOp - Parse a ?: operation. Note that 'LHS' may be null 4835/// in the case of a the GNU conditional expr extension. 4836ExprResult Sema::ActOnConditionalOp(SourceLocation QuestionLoc, 4837 SourceLocation ColonLoc, 4838 Expr *CondExpr, Expr *LHSExpr, 4839 Expr *RHSExpr) { 4840 // If this is the gnu "x ?: y" extension, analyze the types as though the LHS 4841 // was the condition. 4842 OpaqueValueExpr *opaqueValue = 0; 4843 Expr *commonExpr = 0; 4844 if (LHSExpr == 0) { 4845 commonExpr = CondExpr; 4846 4847 // We usually want to apply unary conversions *before* saving, except 4848 // in the special case of a C++ l-value conditional. 4849 if (!(getLangOptions().CPlusPlus 4850 && !commonExpr->isTypeDependent() 4851 && commonExpr->getValueKind() == RHSExpr->getValueKind() 4852 && commonExpr->isGLValue() 4853 && commonExpr->isOrdinaryOrBitFieldObject() 4854 && RHSExpr->isOrdinaryOrBitFieldObject() 4855 && Context.hasSameType(commonExpr->getType(), RHSExpr->getType()))) { 4856 ExprResult commonRes = UsualUnaryConversions(commonExpr); 4857 if (commonRes.isInvalid()) 4858 return ExprError(); 4859 commonExpr = commonRes.take(); 4860 } 4861 4862 opaqueValue = new (Context) OpaqueValueExpr(commonExpr->getExprLoc(), 4863 commonExpr->getType(), 4864 commonExpr->getValueKind(), 4865 commonExpr->getObjectKind()); 4866 LHSExpr = CondExpr = opaqueValue; 4867 } 4868 4869 ExprValueKind VK = VK_RValue; 4870 ExprObjectKind OK = OK_Ordinary; 4871 ExprResult Cond = Owned(CondExpr), LHS = Owned(LHSExpr), RHS = Owned(RHSExpr); 4872 QualType result = CheckConditionalOperands(Cond, LHS, RHS, 4873 VK, OK, QuestionLoc); 4874 if (result.isNull() || Cond.isInvalid() || LHS.isInvalid() || 4875 RHS.isInvalid()) 4876 return ExprError(); 4877 4878 DiagnoseConditionalPrecedence(*this, QuestionLoc, Cond.get(), LHS.get(), 4879 RHS.get()); 4880 4881 if (!commonExpr) 4882 return Owned(new (Context) ConditionalOperator(Cond.take(), QuestionLoc, 4883 LHS.take(), ColonLoc, 4884 RHS.take(), result, VK, OK)); 4885 4886 return Owned(new (Context) 4887 BinaryConditionalOperator(commonExpr, opaqueValue, Cond.take(), LHS.take(), 4888 RHS.take(), QuestionLoc, ColonLoc, result, VK, OK)); 4889} 4890 4891// checkPointerTypesForAssignment - This is a very tricky routine (despite 4892// being closely modeled after the C99 spec:-). The odd characteristic of this 4893// routine is it effectively iqnores the qualifiers on the top level pointee. 4894// This circumvents the usual type rules specified in 6.2.7p1 & 6.7.5.[1-3]. 4895// FIXME: add a couple examples in this comment. 4896static Sema::AssignConvertType 4897checkPointerTypesForAssignment(Sema &S, QualType lhsType, QualType rhsType) { 4898 assert(lhsType.isCanonical() && "LHS not canonicalized!"); 4899 assert(rhsType.isCanonical() && "RHS not canonicalized!"); 4900 4901 // get the "pointed to" type (ignoring qualifiers at the top level) 4902 const Type *lhptee, *rhptee; 4903 Qualifiers lhq, rhq; 4904 llvm::tie(lhptee, lhq) = cast<PointerType>(lhsType)->getPointeeType().split(); 4905 llvm::tie(rhptee, rhq) = cast<PointerType>(rhsType)->getPointeeType().split(); 4906 4907 Sema::AssignConvertType ConvTy = Sema::Compatible; 4908 4909 // C99 6.5.16.1p1: This following citation is common to constraints 4910 // 3 & 4 (below). ...and the type *pointed to* by the left has all the 4911 // qualifiers of the type *pointed to* by the right; 4912 Qualifiers lq; 4913 4914 // As a special case, 'non-__weak A *' -> 'non-__weak const *' is okay. 4915 if (lhq.getObjCLifetime() != rhq.getObjCLifetime() && 4916 lhq.compatiblyIncludesObjCLifetime(rhq)) { 4917 // Ignore lifetime for further calculation. 4918 lhq.removeObjCLifetime(); 4919 rhq.removeObjCLifetime(); 4920 } 4921 4922 if (!lhq.compatiblyIncludes(rhq)) { 4923 // Treat address-space mismatches as fatal. TODO: address subspaces 4924 if (lhq.getAddressSpace() != rhq.getAddressSpace()) 4925 ConvTy = Sema::IncompatiblePointerDiscardsQualifiers; 4926 4927 // It's okay to add or remove GC or lifetime qualifiers when converting to 4928 // and from void*. 4929 else if (lhq.withoutObjCGCAttr().withoutObjCGLifetime() 4930 .compatiblyIncludes( 4931 rhq.withoutObjCGCAttr().withoutObjCGLifetime()) 4932 && (lhptee->isVoidType() || rhptee->isVoidType())) 4933 ; // keep old 4934 4935 // Treat lifetime mismatches as fatal. 4936 else if (lhq.getObjCLifetime() != rhq.getObjCLifetime()) 4937 ConvTy = Sema::IncompatiblePointerDiscardsQualifiers; 4938 4939 // For GCC compatibility, other qualifier mismatches are treated 4940 // as still compatible in C. 4941 else ConvTy = Sema::CompatiblePointerDiscardsQualifiers; 4942 } 4943 4944 // C99 6.5.16.1p1 (constraint 4): If one operand is a pointer to an object or 4945 // incomplete type and the other is a pointer to a qualified or unqualified 4946 // version of void... 4947 if (lhptee->isVoidType()) { 4948 if (rhptee->isIncompleteOrObjectType()) 4949 return ConvTy; 4950 4951 // As an extension, we allow cast to/from void* to function pointer. 4952 assert(rhptee->isFunctionType()); 4953 return Sema::FunctionVoidPointer; 4954 } 4955 4956 if (rhptee->isVoidType()) { 4957 if (lhptee->isIncompleteOrObjectType()) 4958 return ConvTy; 4959 4960 // As an extension, we allow cast to/from void* to function pointer. 4961 assert(lhptee->isFunctionType()); 4962 return Sema::FunctionVoidPointer; 4963 } 4964 4965 // C99 6.5.16.1p1 (constraint 3): both operands are pointers to qualified or 4966 // unqualified versions of compatible types, ... 4967 QualType ltrans = QualType(lhptee, 0), rtrans = QualType(rhptee, 0); 4968 if (!S.Context.typesAreCompatible(ltrans, rtrans)) { 4969 // Check if the pointee types are compatible ignoring the sign. 4970 // We explicitly check for char so that we catch "char" vs 4971 // "unsigned char" on systems where "char" is unsigned. 4972 if (lhptee->isCharType()) 4973 ltrans = S.Context.UnsignedCharTy; 4974 else if (lhptee->hasSignedIntegerRepresentation()) 4975 ltrans = S.Context.getCorrespondingUnsignedType(ltrans); 4976 4977 if (rhptee->isCharType()) 4978 rtrans = S.Context.UnsignedCharTy; 4979 else if (rhptee->hasSignedIntegerRepresentation()) 4980 rtrans = S.Context.getCorrespondingUnsignedType(rtrans); 4981 4982 if (ltrans == rtrans) { 4983 // Types are compatible ignoring the sign. Qualifier incompatibility 4984 // takes priority over sign incompatibility because the sign 4985 // warning can be disabled. 4986 if (ConvTy != Sema::Compatible) 4987 return ConvTy; 4988 4989 return Sema::IncompatiblePointerSign; 4990 } 4991 4992 // If we are a multi-level pointer, it's possible that our issue is simply 4993 // one of qualification - e.g. char ** -> const char ** is not allowed. If 4994 // the eventual target type is the same and the pointers have the same 4995 // level of indirection, this must be the issue. 4996 if (isa<PointerType>(lhptee) && isa<PointerType>(rhptee)) { 4997 do { 4998 lhptee = cast<PointerType>(lhptee)->getPointeeType().getTypePtr(); 4999 rhptee = cast<PointerType>(rhptee)->getPointeeType().getTypePtr(); 5000 } while (isa<PointerType>(lhptee) && isa<PointerType>(rhptee)); 5001 5002 if (lhptee == rhptee) 5003 return Sema::IncompatibleNestedPointerQualifiers; 5004 } 5005 5006 // General pointer incompatibility takes priority over qualifiers. 5007 return Sema::IncompatiblePointer; 5008 } 5009 return ConvTy; 5010} 5011 5012/// checkBlockPointerTypesForAssignment - This routine determines whether two 5013/// block pointer types are compatible or whether a block and normal pointer 5014/// are compatible. It is more restrict than comparing two function pointer 5015// types. 5016static Sema::AssignConvertType 5017checkBlockPointerTypesForAssignment(Sema &S, QualType lhsType, 5018 QualType rhsType) { 5019 assert(lhsType.isCanonical() && "LHS not canonicalized!"); 5020 assert(rhsType.isCanonical() && "RHS not canonicalized!"); 5021 5022 QualType lhptee, rhptee; 5023 5024 // get the "pointed to" type (ignoring qualifiers at the top level) 5025 lhptee = cast<BlockPointerType>(lhsType)->getPointeeType(); 5026 rhptee = cast<BlockPointerType>(rhsType)->getPointeeType(); 5027 5028 // In C++, the types have to match exactly. 5029 if (S.getLangOptions().CPlusPlus) 5030 return Sema::IncompatibleBlockPointer; 5031 5032 Sema::AssignConvertType ConvTy = Sema::Compatible; 5033 5034 // For blocks we enforce that qualifiers are identical. 5035 if (lhptee.getLocalQualifiers() != rhptee.getLocalQualifiers()) 5036 ConvTy = Sema::CompatiblePointerDiscardsQualifiers; 5037 5038 if (!S.Context.typesAreBlockPointerCompatible(lhsType, rhsType)) 5039 return Sema::IncompatibleBlockPointer; 5040 5041 return ConvTy; 5042} 5043 5044/// checkObjCPointerTypesForAssignment - Compares two objective-c pointer types 5045/// for assignment compatibility. 5046static Sema::AssignConvertType 5047checkObjCPointerTypesForAssignment(Sema &S, QualType lhsType, QualType rhsType) { 5048 assert(lhsType.isCanonical() && "LHS was not canonicalized!"); 5049 assert(rhsType.isCanonical() && "RHS was not canonicalized!"); 5050 5051 if (lhsType->isObjCBuiltinType()) { 5052 // Class is not compatible with ObjC object pointers. 5053 if (lhsType->isObjCClassType() && !rhsType->isObjCBuiltinType() && 5054 !rhsType->isObjCQualifiedClassType()) 5055 return Sema::IncompatiblePointer; 5056 return Sema::Compatible; 5057 } 5058 if (rhsType->isObjCBuiltinType()) { 5059 // Class is not compatible with ObjC object pointers. 5060 if (rhsType->isObjCClassType() && !lhsType->isObjCBuiltinType() && 5061 !lhsType->isObjCQualifiedClassType()) 5062 return Sema::IncompatiblePointer; 5063 return Sema::Compatible; 5064 } 5065 QualType lhptee = 5066 lhsType->getAs<ObjCObjectPointerType>()->getPointeeType(); 5067 QualType rhptee = 5068 rhsType->getAs<ObjCObjectPointerType>()->getPointeeType(); 5069 5070 if (!lhptee.isAtLeastAsQualifiedAs(rhptee)) 5071 return Sema::CompatiblePointerDiscardsQualifiers; 5072 5073 if (S.Context.typesAreCompatible(lhsType, rhsType)) 5074 return Sema::Compatible; 5075 if (lhsType->isObjCQualifiedIdType() || rhsType->isObjCQualifiedIdType()) 5076 return Sema::IncompatibleObjCQualifiedId; 5077 return Sema::IncompatiblePointer; 5078} 5079 5080Sema::AssignConvertType 5081Sema::CheckAssignmentConstraints(SourceLocation Loc, 5082 QualType lhsType, QualType rhsType) { 5083 // Fake up an opaque expression. We don't actually care about what 5084 // cast operations are required, so if CheckAssignmentConstraints 5085 // adds casts to this they'll be wasted, but fortunately that doesn't 5086 // usually happen on valid code. 5087 OpaqueValueExpr rhs(Loc, rhsType, VK_RValue); 5088 ExprResult rhsPtr = &rhs; 5089 CastKind K = CK_Invalid; 5090 5091 return CheckAssignmentConstraints(lhsType, rhsPtr, K); 5092} 5093 5094/// CheckAssignmentConstraints (C99 6.5.16) - This routine currently 5095/// has code to accommodate several GCC extensions when type checking 5096/// pointers. Here are some objectionable examples that GCC considers warnings: 5097/// 5098/// int a, *pint; 5099/// short *pshort; 5100/// struct foo *pfoo; 5101/// 5102/// pint = pshort; // warning: assignment from incompatible pointer type 5103/// a = pint; // warning: assignment makes integer from pointer without a cast 5104/// pint = a; // warning: assignment makes pointer from integer without a cast 5105/// pint = pfoo; // warning: assignment from incompatible pointer type 5106/// 5107/// As a result, the code for dealing with pointers is more complex than the 5108/// C99 spec dictates. 5109/// 5110/// Sets 'Kind' for any result kind except Incompatible. 5111Sema::AssignConvertType 5112Sema::CheckAssignmentConstraints(QualType lhsType, ExprResult &rhs, 5113 CastKind &Kind) { 5114 QualType rhsType = rhs.get()->getType(); 5115 QualType origLhsType = lhsType; 5116 5117 // Get canonical types. We're not formatting these types, just comparing 5118 // them. 5119 lhsType = Context.getCanonicalType(lhsType).getUnqualifiedType(); 5120 rhsType = Context.getCanonicalType(rhsType).getUnqualifiedType(); 5121 5122 // Common case: no conversion required. 5123 if (lhsType == rhsType) { 5124 Kind = CK_NoOp; 5125 return Compatible; 5126 } 5127 5128 // If the left-hand side is a reference type, then we are in a 5129 // (rare!) case where we've allowed the use of references in C, 5130 // e.g., as a parameter type in a built-in function. In this case, 5131 // just make sure that the type referenced is compatible with the 5132 // right-hand side type. The caller is responsible for adjusting 5133 // lhsType so that the resulting expression does not have reference 5134 // type. 5135 if (const ReferenceType *lhsTypeRef = lhsType->getAs<ReferenceType>()) { 5136 if (Context.typesAreCompatible(lhsTypeRef->getPointeeType(), rhsType)) { 5137 Kind = CK_LValueBitCast; 5138 return Compatible; 5139 } 5140 return Incompatible; 5141 } 5142 5143 // Allow scalar to ExtVector assignments, and assignments of an ExtVector type 5144 // to the same ExtVector type. 5145 if (lhsType->isExtVectorType()) { 5146 if (rhsType->isExtVectorType()) 5147 return Incompatible; 5148 if (rhsType->isArithmeticType()) { 5149 // CK_VectorSplat does T -> vector T, so first cast to the 5150 // element type. 5151 QualType elType = cast<ExtVectorType>(lhsType)->getElementType(); 5152 if (elType != rhsType) { 5153 Kind = PrepareScalarCast(*this, rhs, elType); 5154 rhs = ImpCastExprToType(rhs.take(), elType, Kind); 5155 } 5156 Kind = CK_VectorSplat; 5157 return Compatible; 5158 } 5159 } 5160 5161 // Conversions to or from vector type. 5162 if (lhsType->isVectorType() || rhsType->isVectorType()) { 5163 if (lhsType->isVectorType() && rhsType->isVectorType()) { 5164 // Allow assignments of an AltiVec vector type to an equivalent GCC 5165 // vector type and vice versa 5166 if (Context.areCompatibleVectorTypes(lhsType, rhsType)) { 5167 Kind = CK_BitCast; 5168 return Compatible; 5169 } 5170 5171 // If we are allowing lax vector conversions, and LHS and RHS are both 5172 // vectors, the total size only needs to be the same. This is a bitcast; 5173 // no bits are changed but the result type is different. 5174 if (getLangOptions().LaxVectorConversions && 5175 (Context.getTypeSize(lhsType) == Context.getTypeSize(rhsType))) { 5176 Kind = CK_BitCast; 5177 return IncompatibleVectors; 5178 } 5179 } 5180 return Incompatible; 5181 } 5182 5183 // Arithmetic conversions. 5184 if (lhsType->isArithmeticType() && rhsType->isArithmeticType() && 5185 !(getLangOptions().CPlusPlus && lhsType->isEnumeralType())) { 5186 Kind = PrepareScalarCast(*this, rhs, lhsType); 5187 return Compatible; 5188 } 5189 5190 // Conversions to normal pointers. 5191 if (const PointerType *lhsPointer = dyn_cast<PointerType>(lhsType)) { 5192 // U* -> T* 5193 if (isa<PointerType>(rhsType)) { 5194 Kind = CK_BitCast; 5195 return checkPointerTypesForAssignment(*this, lhsType, rhsType); 5196 } 5197 5198 // int -> T* 5199 if (rhsType->isIntegerType()) { 5200 Kind = CK_IntegralToPointer; // FIXME: null? 5201 return IntToPointer; 5202 } 5203 5204 // C pointers are not compatible with ObjC object pointers, 5205 // with two exceptions: 5206 if (isa<ObjCObjectPointerType>(rhsType)) { 5207 // - conversions to void* 5208 if (lhsPointer->getPointeeType()->isVoidType()) { 5209 Kind = CK_AnyPointerToObjCPointerCast; 5210 return Compatible; 5211 } 5212 5213 // - conversions from 'Class' to the redefinition type 5214 if (rhsType->isObjCClassType() && 5215 Context.hasSameType(lhsType, Context.ObjCClassRedefinitionType)) { 5216 Kind = CK_BitCast; 5217 return Compatible; 5218 } 5219 5220 Kind = CK_BitCast; 5221 return IncompatiblePointer; 5222 } 5223 5224 // U^ -> void* 5225 if (rhsType->getAs<BlockPointerType>()) { 5226 if (lhsPointer->getPointeeType()->isVoidType()) { 5227 Kind = CK_BitCast; 5228 return Compatible; 5229 } 5230 } 5231 5232 return Incompatible; 5233 } 5234 5235 // Conversions to block pointers. 5236 if (isa<BlockPointerType>(lhsType)) { 5237 // U^ -> T^ 5238 if (rhsType->isBlockPointerType()) { 5239 Kind = CK_AnyPointerToBlockPointerCast; 5240 return checkBlockPointerTypesForAssignment(*this, lhsType, rhsType); 5241 } 5242 5243 // int or null -> T^ 5244 if (rhsType->isIntegerType()) { 5245 Kind = CK_IntegralToPointer; // FIXME: null 5246 return IntToBlockPointer; 5247 } 5248 5249 // id -> T^ 5250 if (getLangOptions().ObjC1 && rhsType->isObjCIdType()) { 5251 Kind = CK_AnyPointerToBlockPointerCast; 5252 return Compatible; 5253 } 5254 5255 // void* -> T^ 5256 if (const PointerType *RHSPT = rhsType->getAs<PointerType>()) 5257 if (RHSPT->getPointeeType()->isVoidType()) { 5258 Kind = CK_AnyPointerToBlockPointerCast; 5259 return Compatible; 5260 } 5261 5262 return Incompatible; 5263 } 5264 5265 // Conversions to Objective-C pointers. 5266 if (isa<ObjCObjectPointerType>(lhsType)) { 5267 // A* -> B* 5268 if (rhsType->isObjCObjectPointerType()) { 5269 Kind = CK_BitCast; 5270 Sema::AssignConvertType result = 5271 checkObjCPointerTypesForAssignment(*this, lhsType, rhsType); 5272 if (getLangOptions().ObjCAutoRefCount && 5273 result == Compatible && 5274 !CheckObjCARCUnavailableWeakConversion(origLhsType, rhsType)) 5275 result = IncompatibleObjCWeakRef; 5276 return result; 5277 } 5278 5279 // int or null -> A* 5280 if (rhsType->isIntegerType()) { 5281 Kind = CK_IntegralToPointer; // FIXME: null 5282 return IntToPointer; 5283 } 5284 5285 // In general, C pointers are not compatible with ObjC object pointers, 5286 // with two exceptions: 5287 if (isa<PointerType>(rhsType)) { 5288 // - conversions from 'void*' 5289 if (rhsType->isVoidPointerType()) { 5290 Kind = CK_AnyPointerToObjCPointerCast; 5291 return Compatible; 5292 } 5293 5294 // - conversions to 'Class' from its redefinition type 5295 if (lhsType->isObjCClassType() && 5296 Context.hasSameType(rhsType, Context.ObjCClassRedefinitionType)) { 5297 Kind = CK_BitCast; 5298 return Compatible; 5299 } 5300 5301 Kind = CK_AnyPointerToObjCPointerCast; 5302 return IncompatiblePointer; 5303 } 5304 5305 // T^ -> A* 5306 if (rhsType->isBlockPointerType()) { 5307 Kind = CK_AnyPointerToObjCPointerCast; 5308 return Compatible; 5309 } 5310 5311 return Incompatible; 5312 } 5313 5314 // Conversions from pointers that are not covered by the above. 5315 if (isa<PointerType>(rhsType)) { 5316 // T* -> _Bool 5317 if (lhsType == Context.BoolTy) { 5318 Kind = CK_PointerToBoolean; 5319 return Compatible; 5320 } 5321 5322 // T* -> int 5323 if (lhsType->isIntegerType()) { 5324 Kind = CK_PointerToIntegral; 5325 return PointerToInt; 5326 } 5327 5328 return Incompatible; 5329 } 5330 5331 // Conversions from Objective-C pointers that are not covered by the above. 5332 if (isa<ObjCObjectPointerType>(rhsType)) { 5333 // T* -> _Bool 5334 if (lhsType == Context.BoolTy) { 5335 Kind = CK_PointerToBoolean; 5336 return Compatible; 5337 } 5338 5339 // T* -> int 5340 if (lhsType->isIntegerType()) { 5341 Kind = CK_PointerToIntegral; 5342 return PointerToInt; 5343 } 5344 5345 return Incompatible; 5346 } 5347 5348 // struct A -> struct B 5349 if (isa<TagType>(lhsType) && isa<TagType>(rhsType)) { 5350 if (Context.typesAreCompatible(lhsType, rhsType)) { 5351 Kind = CK_NoOp; 5352 return Compatible; 5353 } 5354 } 5355 5356 return Incompatible; 5357} 5358 5359/// \brief Constructs a transparent union from an expression that is 5360/// used to initialize the transparent union. 5361static void ConstructTransparentUnion(Sema &S, ASTContext &C, ExprResult &EResult, 5362 QualType UnionType, FieldDecl *Field) { 5363 // Build an initializer list that designates the appropriate member 5364 // of the transparent union. 5365 Expr *E = EResult.take(); 5366 InitListExpr *Initializer = new (C) InitListExpr(C, SourceLocation(), 5367 &E, 1, 5368 SourceLocation()); 5369 Initializer->setType(UnionType); 5370 Initializer->setInitializedFieldInUnion(Field); 5371 5372 // Build a compound literal constructing a value of the transparent 5373 // union type from this initializer list. 5374 TypeSourceInfo *unionTInfo = C.getTrivialTypeSourceInfo(UnionType); 5375 EResult = S.Owned( 5376 new (C) CompoundLiteralExpr(SourceLocation(), unionTInfo, UnionType, 5377 VK_RValue, Initializer, false)); 5378} 5379 5380Sema::AssignConvertType 5381Sema::CheckTransparentUnionArgumentConstraints(QualType ArgType, ExprResult &rExpr) { 5382 QualType FromType = rExpr.get()->getType(); 5383 5384 // If the ArgType is a Union type, we want to handle a potential 5385 // transparent_union GCC extension. 5386 const RecordType *UT = ArgType->getAsUnionType(); 5387 if (!UT || !UT->getDecl()->hasAttr<TransparentUnionAttr>()) 5388 return Incompatible; 5389 5390 // The field to initialize within the transparent union. 5391 RecordDecl *UD = UT->getDecl(); 5392 FieldDecl *InitField = 0; 5393 // It's compatible if the expression matches any of the fields. 5394 for (RecordDecl::field_iterator it = UD->field_begin(), 5395 itend = UD->field_end(); 5396 it != itend; ++it) { 5397 if (it->getType()->isPointerType()) { 5398 // If the transparent union contains a pointer type, we allow: 5399 // 1) void pointer 5400 // 2) null pointer constant 5401 if (FromType->isPointerType()) 5402 if (FromType->getAs<PointerType>()->getPointeeType()->isVoidType()) { 5403 rExpr = ImpCastExprToType(rExpr.take(), it->getType(), CK_BitCast); 5404 InitField = *it; 5405 break; 5406 } 5407 5408 if (rExpr.get()->isNullPointerConstant(Context, 5409 Expr::NPC_ValueDependentIsNull)) { 5410 rExpr = ImpCastExprToType(rExpr.take(), it->getType(), CK_NullToPointer); 5411 InitField = *it; 5412 break; 5413 } 5414 } 5415 5416 CastKind Kind = CK_Invalid; 5417 if (CheckAssignmentConstraints(it->getType(), rExpr, Kind) 5418 == Compatible) { 5419 rExpr = ImpCastExprToType(rExpr.take(), it->getType(), Kind); 5420 InitField = *it; 5421 break; 5422 } 5423 } 5424 5425 if (!InitField) 5426 return Incompatible; 5427 5428 ConstructTransparentUnion(*this, Context, rExpr, ArgType, InitField); 5429 return Compatible; 5430} 5431 5432Sema::AssignConvertType 5433Sema::CheckSingleAssignmentConstraints(QualType lhsType, ExprResult &rExpr) { 5434 if (getLangOptions().CPlusPlus) { 5435 if (!lhsType->isRecordType()) { 5436 // C++ 5.17p3: If the left operand is not of class type, the 5437 // expression is implicitly converted (C++ 4) to the 5438 // cv-unqualified type of the left operand. 5439 ExprResult Res = PerformImplicitConversion(rExpr.get(), 5440 lhsType.getUnqualifiedType(), 5441 AA_Assigning); 5442 if (Res.isInvalid()) 5443 return Incompatible; 5444 Sema::AssignConvertType result = Compatible; 5445 if (getLangOptions().ObjCAutoRefCount && 5446 !CheckObjCARCUnavailableWeakConversion(lhsType, rExpr.get()->getType())) 5447 result = IncompatibleObjCWeakRef; 5448 rExpr = move(Res); 5449 return result; 5450 } 5451 5452 // FIXME: Currently, we fall through and treat C++ classes like C 5453 // structures. 5454 } 5455 5456 // C99 6.5.16.1p1: the left operand is a pointer and the right is 5457 // a null pointer constant. 5458 if ((lhsType->isPointerType() || 5459 lhsType->isObjCObjectPointerType() || 5460 lhsType->isBlockPointerType()) 5461 && rExpr.get()->isNullPointerConstant(Context, 5462 Expr::NPC_ValueDependentIsNull)) { 5463 rExpr = ImpCastExprToType(rExpr.take(), lhsType, CK_NullToPointer); 5464 return Compatible; 5465 } 5466 5467 // This check seems unnatural, however it is necessary to ensure the proper 5468 // conversion of functions/arrays. If the conversion were done for all 5469 // DeclExpr's (created by ActOnIdExpression), it would mess up the unary 5470 // expressions that suppress this implicit conversion (&, sizeof). 5471 // 5472 // Suppress this for references: C++ 8.5.3p5. 5473 if (!lhsType->isReferenceType()) { 5474 rExpr = DefaultFunctionArrayLvalueConversion(rExpr.take()); 5475 if (rExpr.isInvalid()) 5476 return Incompatible; 5477 } 5478 5479 CastKind Kind = CK_Invalid; 5480 Sema::AssignConvertType result = 5481 CheckAssignmentConstraints(lhsType, rExpr, Kind); 5482 5483 // C99 6.5.16.1p2: The value of the right operand is converted to the 5484 // type of the assignment expression. 5485 // CheckAssignmentConstraints allows the left-hand side to be a reference, 5486 // so that we can use references in built-in functions even in C. 5487 // The getNonReferenceType() call makes sure that the resulting expression 5488 // does not have reference type. 5489 if (result != Incompatible && rExpr.get()->getType() != lhsType) 5490 rExpr = ImpCastExprToType(rExpr.take(), lhsType.getNonLValueExprType(Context), Kind); 5491 return result; 5492} 5493 5494QualType Sema::InvalidOperands(SourceLocation Loc, ExprResult &lex, ExprResult &rex) { 5495 Diag(Loc, diag::err_typecheck_invalid_operands) 5496 << lex.get()->getType() << rex.get()->getType() 5497 << lex.get()->getSourceRange() << rex.get()->getSourceRange(); 5498 return QualType(); 5499} 5500 5501QualType Sema::CheckVectorOperands(ExprResult &lex, ExprResult &rex, 5502 SourceLocation Loc, bool isCompAssign) { 5503 // For conversion purposes, we ignore any qualifiers. 5504 // For example, "const float" and "float" are equivalent. 5505 QualType lhsType = 5506 Context.getCanonicalType(lex.get()->getType()).getUnqualifiedType(); 5507 QualType rhsType = 5508 Context.getCanonicalType(rex.get()->getType()).getUnqualifiedType(); 5509 5510 // If the vector types are identical, return. 5511 if (lhsType == rhsType) 5512 return lhsType; 5513 5514 // Handle the case of equivalent AltiVec and GCC vector types 5515 if (lhsType->isVectorType() && rhsType->isVectorType() && 5516 Context.areCompatibleVectorTypes(lhsType, rhsType)) { 5517 if (lhsType->isExtVectorType()) { 5518 rex = ImpCastExprToType(rex.take(), lhsType, CK_BitCast); 5519 return lhsType; 5520 } 5521 5522 if (!isCompAssign) 5523 lex = ImpCastExprToType(lex.take(), rhsType, CK_BitCast); 5524 return rhsType; 5525 } 5526 5527 if (getLangOptions().LaxVectorConversions && 5528 Context.getTypeSize(lhsType) == Context.getTypeSize(rhsType)) { 5529 // If we are allowing lax vector conversions, and LHS and RHS are both 5530 // vectors, the total size only needs to be the same. This is a 5531 // bitcast; no bits are changed but the result type is different. 5532 // FIXME: Should we really be allowing this? 5533 rex = ImpCastExprToType(rex.take(), lhsType, CK_BitCast); 5534 return lhsType; 5535 } 5536 5537 // Canonicalize the ExtVector to the LHS, remember if we swapped so we can 5538 // swap back (so that we don't reverse the inputs to a subtract, for instance. 5539 bool swapped = false; 5540 if (rhsType->isExtVectorType() && !isCompAssign) { 5541 swapped = true; 5542 std::swap(rex, lex); 5543 std::swap(rhsType, lhsType); 5544 } 5545 5546 // Handle the case of an ext vector and scalar. 5547 if (const ExtVectorType *LV = lhsType->getAs<ExtVectorType>()) { 5548 QualType EltTy = LV->getElementType(); 5549 if (EltTy->isIntegralType(Context) && rhsType->isIntegralType(Context)) { 5550 int order = Context.getIntegerTypeOrder(EltTy, rhsType); 5551 if (order > 0) 5552 rex = ImpCastExprToType(rex.take(), EltTy, CK_IntegralCast); 5553 if (order >= 0) { 5554 rex = ImpCastExprToType(rex.take(), lhsType, CK_VectorSplat); 5555 if (swapped) std::swap(rex, lex); 5556 return lhsType; 5557 } 5558 } 5559 if (EltTy->isRealFloatingType() && rhsType->isScalarType() && 5560 rhsType->isRealFloatingType()) { 5561 int order = Context.getFloatingTypeOrder(EltTy, rhsType); 5562 if (order > 0) 5563 rex = ImpCastExprToType(rex.take(), EltTy, CK_FloatingCast); 5564 if (order >= 0) { 5565 rex = ImpCastExprToType(rex.take(), lhsType, CK_VectorSplat); 5566 if (swapped) std::swap(rex, lex); 5567 return lhsType; 5568 } 5569 } 5570 } 5571 5572 // Vectors of different size or scalar and non-ext-vector are errors. 5573 if (swapped) std::swap(rex, lex); 5574 Diag(Loc, diag::err_typecheck_vector_not_convertable) 5575 << lex.get()->getType() << rex.get()->getType() 5576 << lex.get()->getSourceRange() << rex.get()->getSourceRange(); 5577 return QualType(); 5578} 5579 5580QualType Sema::CheckMultiplyDivideOperands( 5581 ExprResult &lex, ExprResult &rex, SourceLocation Loc, bool isCompAssign, bool isDiv) { 5582 if (lex.get()->getType()->isVectorType() || rex.get()->getType()->isVectorType()) 5583 return CheckVectorOperands(lex, rex, Loc, isCompAssign); 5584 5585 QualType compType = UsualArithmeticConversions(lex, rex, isCompAssign); 5586 if (lex.isInvalid() || rex.isInvalid()) 5587 return QualType(); 5588 5589 if (!lex.get()->getType()->isArithmeticType() || 5590 !rex.get()->getType()->isArithmeticType()) 5591 return InvalidOperands(Loc, lex, rex); 5592 5593 // Check for division by zero. 5594 if (isDiv && 5595 rex.get()->isNullPointerConstant(Context, Expr::NPC_ValueDependentIsNotNull)) 5596 DiagRuntimeBehavior(Loc, rex.get(), PDiag(diag::warn_division_by_zero) 5597 << rex.get()->getSourceRange()); 5598 5599 return compType; 5600} 5601 5602QualType Sema::CheckRemainderOperands( 5603 ExprResult &lex, ExprResult &rex, SourceLocation Loc, bool isCompAssign) { 5604 if (lex.get()->getType()->isVectorType() || rex.get()->getType()->isVectorType()) { 5605 if (lex.get()->getType()->hasIntegerRepresentation() && 5606 rex.get()->getType()->hasIntegerRepresentation()) 5607 return CheckVectorOperands(lex, rex, Loc, isCompAssign); 5608 return InvalidOperands(Loc, lex, rex); 5609 } 5610 5611 QualType compType = UsualArithmeticConversions(lex, rex, isCompAssign); 5612 if (lex.isInvalid() || rex.isInvalid()) 5613 return QualType(); 5614 5615 if (!lex.get()->getType()->isIntegerType() || !rex.get()->getType()->isIntegerType()) 5616 return InvalidOperands(Loc, lex, rex); 5617 5618 // Check for remainder by zero. 5619 if (rex.get()->isNullPointerConstant(Context, Expr::NPC_ValueDependentIsNotNull)) 5620 DiagRuntimeBehavior(Loc, rex.get(), PDiag(diag::warn_remainder_by_zero) 5621 << rex.get()->getSourceRange()); 5622 5623 return compType; 5624} 5625 5626/// \brief Diagnose invalid arithmetic on two void pointers. 5627static void diagnoseArithmeticOnTwoVoidPointers(Sema &S, SourceLocation Loc, 5628 Expr *LHS, Expr *RHS) { 5629 S.Diag(Loc, S.getLangOptions().CPlusPlus 5630 ? diag::err_typecheck_pointer_arith_void_type 5631 : diag::ext_gnu_void_ptr) 5632 << 1 /* two pointers */ << LHS->getSourceRange() << RHS->getSourceRange(); 5633} 5634 5635/// \brief Diagnose invalid arithmetic on a void pointer. 5636static void diagnoseArithmeticOnVoidPointer(Sema &S, SourceLocation Loc, 5637 Expr *Pointer) { 5638 S.Diag(Loc, S.getLangOptions().CPlusPlus 5639 ? diag::err_typecheck_pointer_arith_void_type 5640 : diag::ext_gnu_void_ptr) 5641 << 0 /* one pointer */ << Pointer->getSourceRange(); 5642} 5643 5644/// \brief Diagnose invalid arithmetic on two function pointers. 5645static void diagnoseArithmeticOnTwoFunctionPointers(Sema &S, SourceLocation Loc, 5646 Expr *LHS, Expr *RHS) { 5647 assert(LHS->getType()->isAnyPointerType()); 5648 assert(RHS->getType()->isAnyPointerType()); 5649 S.Diag(Loc, S.getLangOptions().CPlusPlus 5650 ? diag::err_typecheck_pointer_arith_function_type 5651 : diag::ext_gnu_ptr_func_arith) 5652 << 1 /* two pointers */ << LHS->getType()->getPointeeType() 5653 // We only show the second type if it differs from the first. 5654 << (unsigned)!S.Context.hasSameUnqualifiedType(LHS->getType(), 5655 RHS->getType()) 5656 << RHS->getType()->getPointeeType() 5657 << LHS->getSourceRange() << RHS->getSourceRange(); 5658} 5659 5660/// \brief Diagnose invalid arithmetic on a function pointer. 5661static void diagnoseArithmeticOnFunctionPointer(Sema &S, SourceLocation Loc, 5662 Expr *Pointer) { 5663 assert(Pointer->getType()->isAnyPointerType()); 5664 S.Diag(Loc, S.getLangOptions().CPlusPlus 5665 ? diag::err_typecheck_pointer_arith_function_type 5666 : diag::ext_gnu_ptr_func_arith) 5667 << 0 /* one pointer */ << Pointer->getType()->getPointeeType() 5668 << 0 /* one pointer, so only one type */ 5669 << Pointer->getSourceRange(); 5670} 5671 5672/// \brief Check the validity of an arithmetic pointer operand. 5673/// 5674/// If the operand has pointer type, this code will check for pointer types 5675/// which are invalid in arithmetic operations. These will be diagnosed 5676/// appropriately, including whether or not the use is supported as an 5677/// extension. 5678/// 5679/// \returns True when the operand is valid to use (even if as an extension). 5680static bool checkArithmeticOpPointerOperand(Sema &S, SourceLocation Loc, 5681 Expr *Operand) { 5682 if (!Operand->getType()->isAnyPointerType()) return true; 5683 5684 QualType PointeeTy = Operand->getType()->getPointeeType(); 5685 if (PointeeTy->isVoidType()) { 5686 diagnoseArithmeticOnVoidPointer(S, Loc, Operand); 5687 return !S.getLangOptions().CPlusPlus; 5688 } 5689 if (PointeeTy->isFunctionType()) { 5690 diagnoseArithmeticOnFunctionPointer(S, Loc, Operand); 5691 return !S.getLangOptions().CPlusPlus; 5692 } 5693 5694 if ((Operand->getType()->isPointerType() && 5695 !Operand->getType()->isDependentType()) || 5696 Operand->getType()->isObjCObjectPointerType()) { 5697 QualType PointeeTy = Operand->getType()->getPointeeType(); 5698 if (S.RequireCompleteType( 5699 Loc, PointeeTy, 5700 S.PDiag(diag::err_typecheck_arithmetic_incomplete_type) 5701 << PointeeTy << Operand->getSourceRange())) 5702 return false; 5703 } 5704 5705 return true; 5706} 5707 5708/// \brief Check the validity of a binary arithmetic operation w.r.t. pointer 5709/// operands. 5710/// 5711/// This routine will diagnose any invalid arithmetic on pointer operands much 5712/// like \see checkArithmeticOpPointerOperand. However, it has special logic 5713/// for emitting a single diagnostic even for operations where both LHS and RHS 5714/// are (potentially problematic) pointers. 5715/// 5716/// \returns True when the operand is valid to use (even if as an extension). 5717static bool checkArithmeticBinOpPointerOperands(Sema &S, SourceLocation Loc, 5718 Expr *LHS, Expr *RHS) { 5719 bool isLHSPointer = LHS->getType()->isAnyPointerType(); 5720 bool isRHSPointer = RHS->getType()->isAnyPointerType(); 5721 if (!isLHSPointer && !isRHSPointer) return true; 5722 5723 QualType LHSPointeeTy, RHSPointeeTy; 5724 if (isLHSPointer) LHSPointeeTy = LHS->getType()->getPointeeType(); 5725 if (isRHSPointer) RHSPointeeTy = RHS->getType()->getPointeeType(); 5726 5727 // Check for arithmetic on pointers to incomplete types. 5728 bool isLHSVoidPtr = isLHSPointer && LHSPointeeTy->isVoidType(); 5729 bool isRHSVoidPtr = isRHSPointer && RHSPointeeTy->isVoidType(); 5730 if (isLHSVoidPtr || isRHSVoidPtr) { 5731 if (!isRHSVoidPtr) diagnoseArithmeticOnVoidPointer(S, Loc, LHS); 5732 else if (!isLHSVoidPtr) diagnoseArithmeticOnVoidPointer(S, Loc, RHS); 5733 else diagnoseArithmeticOnTwoVoidPointers(S, Loc, LHS, RHS); 5734 5735 return !S.getLangOptions().CPlusPlus; 5736 } 5737 5738 bool isLHSFuncPtr = isLHSPointer && LHSPointeeTy->isFunctionType(); 5739 bool isRHSFuncPtr = isRHSPointer && RHSPointeeTy->isFunctionType(); 5740 if (isLHSFuncPtr || isRHSFuncPtr) { 5741 if (!isRHSFuncPtr) diagnoseArithmeticOnFunctionPointer(S, Loc, LHS); 5742 else if (!isLHSFuncPtr) diagnoseArithmeticOnFunctionPointer(S, Loc, RHS); 5743 else diagnoseArithmeticOnTwoFunctionPointers(S, Loc, LHS, RHS); 5744 5745 return !S.getLangOptions().CPlusPlus; 5746 } 5747 5748 Expr *Operands[] = { LHS, RHS }; 5749 for (unsigned i = 0; i < 2; ++i) { 5750 Expr *Operand = Operands[i]; 5751 if ((Operand->getType()->isPointerType() && 5752 !Operand->getType()->isDependentType()) || 5753 Operand->getType()->isObjCObjectPointerType()) { 5754 QualType PointeeTy = Operand->getType()->getPointeeType(); 5755 if (S.RequireCompleteType( 5756 Loc, PointeeTy, 5757 S.PDiag(diag::err_typecheck_arithmetic_incomplete_type) 5758 << PointeeTy << Operand->getSourceRange())) 5759 return false; 5760 } 5761 } 5762 return true; 5763} 5764 5765QualType Sema::CheckAdditionOperands( // C99 6.5.6 5766 ExprResult &lex, ExprResult &rex, SourceLocation Loc, QualType* CompLHSTy) { 5767 if (lex.get()->getType()->isVectorType() || rex.get()->getType()->isVectorType()) { 5768 QualType compType = CheckVectorOperands(lex, rex, Loc, CompLHSTy); 5769 if (CompLHSTy) *CompLHSTy = compType; 5770 return compType; 5771 } 5772 5773 QualType compType = UsualArithmeticConversions(lex, rex, CompLHSTy); 5774 if (lex.isInvalid() || rex.isInvalid()) 5775 return QualType(); 5776 5777 // handle the common case first (both operands are arithmetic). 5778 if (lex.get()->getType()->isArithmeticType() && 5779 rex.get()->getType()->isArithmeticType()) { 5780 if (CompLHSTy) *CompLHSTy = compType; 5781 return compType; 5782 } 5783 5784 // Put any potential pointer into PExp 5785 Expr* PExp = lex.get(), *IExp = rex.get(); 5786 if (IExp->getType()->isAnyPointerType()) 5787 std::swap(PExp, IExp); 5788 5789 if (PExp->getType()->isAnyPointerType()) { 5790 if (IExp->getType()->isIntegerType()) { 5791 if (!checkArithmeticOpPointerOperand(*this, Loc, PExp)) 5792 return QualType(); 5793 5794 QualType PointeeTy = PExp->getType()->getPointeeType(); 5795 5796 // Diagnose bad cases where we step over interface counts. 5797 if (PointeeTy->isObjCObjectType() && LangOpts.ObjCNonFragileABI) { 5798 Diag(Loc, diag::err_arithmetic_nonfragile_interface) 5799 << PointeeTy << PExp->getSourceRange(); 5800 return QualType(); 5801 } 5802 5803 if (CompLHSTy) { 5804 QualType LHSTy = Context.isPromotableBitField(lex.get()); 5805 if (LHSTy.isNull()) { 5806 LHSTy = lex.get()->getType(); 5807 if (LHSTy->isPromotableIntegerType()) 5808 LHSTy = Context.getPromotedIntegerType(LHSTy); 5809 } 5810 *CompLHSTy = LHSTy; 5811 } 5812 return PExp->getType(); 5813 } 5814 } 5815 5816 return InvalidOperands(Loc, lex, rex); 5817} 5818 5819// C99 6.5.6 5820QualType Sema::CheckSubtractionOperands(ExprResult &lex, ExprResult &rex, 5821 SourceLocation Loc, QualType* CompLHSTy) { 5822 if (lex.get()->getType()->isVectorType() || rex.get()->getType()->isVectorType()) { 5823 QualType compType = CheckVectorOperands(lex, rex, Loc, CompLHSTy); 5824 if (CompLHSTy) *CompLHSTy = compType; 5825 return compType; 5826 } 5827 5828 QualType compType = UsualArithmeticConversions(lex, rex, CompLHSTy); 5829 if (lex.isInvalid() || rex.isInvalid()) 5830 return QualType(); 5831 5832 // Enforce type constraints: C99 6.5.6p3. 5833 5834 // Handle the common case first (both operands are arithmetic). 5835 if (lex.get()->getType()->isArithmeticType() && 5836 rex.get()->getType()->isArithmeticType()) { 5837 if (CompLHSTy) *CompLHSTy = compType; 5838 return compType; 5839 } 5840 5841 // Either ptr - int or ptr - ptr. 5842 if (lex.get()->getType()->isAnyPointerType()) { 5843 QualType lpointee = lex.get()->getType()->getPointeeType(); 5844 5845 // Diagnose bad cases where we step over interface counts. 5846 if (lpointee->isObjCObjectType() && LangOpts.ObjCNonFragileABI) { 5847 Diag(Loc, diag::err_arithmetic_nonfragile_interface) 5848 << lpointee << lex.get()->getSourceRange(); 5849 return QualType(); 5850 } 5851 5852 // The result type of a pointer-int computation is the pointer type. 5853 if (rex.get()->getType()->isIntegerType()) { 5854 if (!checkArithmeticOpPointerOperand(*this, Loc, lex.get())) 5855 return QualType(); 5856 5857 if (CompLHSTy) *CompLHSTy = lex.get()->getType(); 5858 return lex.get()->getType(); 5859 } 5860 5861 // Handle pointer-pointer subtractions. 5862 if (const PointerType *RHSPTy = rex.get()->getType()->getAs<PointerType>()) { 5863 QualType rpointee = RHSPTy->getPointeeType(); 5864 5865 if (getLangOptions().CPlusPlus) { 5866 // Pointee types must be the same: C++ [expr.add] 5867 if (!Context.hasSameUnqualifiedType(lpointee, rpointee)) { 5868 Diag(Loc, diag::err_typecheck_sub_ptr_compatible) 5869 << lex.get()->getType() << rex.get()->getType() 5870 << lex.get()->getSourceRange() << rex.get()->getSourceRange(); 5871 return QualType(); 5872 } 5873 } else { 5874 // Pointee types must be compatible C99 6.5.6p3 5875 if (!Context.typesAreCompatible( 5876 Context.getCanonicalType(lpointee).getUnqualifiedType(), 5877 Context.getCanonicalType(rpointee).getUnqualifiedType())) { 5878 Diag(Loc, diag::err_typecheck_sub_ptr_compatible) 5879 << lex.get()->getType() << rex.get()->getType() 5880 << lex.get()->getSourceRange() << rex.get()->getSourceRange(); 5881 return QualType(); 5882 } 5883 } 5884 5885 if (!checkArithmeticBinOpPointerOperands(*this, Loc, 5886 lex.get(), rex.get())) 5887 return QualType(); 5888 5889 if (CompLHSTy) *CompLHSTy = lex.get()->getType(); 5890 return Context.getPointerDiffType(); 5891 } 5892 } 5893 5894 return InvalidOperands(Loc, lex, rex); 5895} 5896 5897static bool isScopedEnumerationType(QualType T) { 5898 if (const EnumType *ET = dyn_cast<EnumType>(T)) 5899 return ET->getDecl()->isScoped(); 5900 return false; 5901} 5902 5903static void DiagnoseBadShiftValues(Sema& S, ExprResult &lex, ExprResult &rex, 5904 SourceLocation Loc, unsigned Opc, 5905 QualType LHSTy) { 5906 llvm::APSInt Right; 5907 // Check right/shifter operand 5908 if (rex.get()->isValueDependent() || !rex.get()->isIntegerConstantExpr(Right, S.Context)) 5909 return; 5910 5911 if (Right.isNegative()) { 5912 S.DiagRuntimeBehavior(Loc, rex.get(), 5913 S.PDiag(diag::warn_shift_negative) 5914 << rex.get()->getSourceRange()); 5915 return; 5916 } 5917 llvm::APInt LeftBits(Right.getBitWidth(), 5918 S.Context.getTypeSize(lex.get()->getType())); 5919 if (Right.uge(LeftBits)) { 5920 S.DiagRuntimeBehavior(Loc, rex.get(), 5921 S.PDiag(diag::warn_shift_gt_typewidth) 5922 << rex.get()->getSourceRange()); 5923 return; 5924 } 5925 if (Opc != BO_Shl) 5926 return; 5927 5928 // When left shifting an ICE which is signed, we can check for overflow which 5929 // according to C++ has undefined behavior ([expr.shift] 5.8/2). Unsigned 5930 // integers have defined behavior modulo one more than the maximum value 5931 // representable in the result type, so never warn for those. 5932 llvm::APSInt Left; 5933 if (lex.get()->isValueDependent() || !lex.get()->isIntegerConstantExpr(Left, S.Context) || 5934 LHSTy->hasUnsignedIntegerRepresentation()) 5935 return; 5936 llvm::APInt ResultBits = 5937 static_cast<llvm::APInt&>(Right) + Left.getMinSignedBits(); 5938 if (LeftBits.uge(ResultBits)) 5939 return; 5940 llvm::APSInt Result = Left.extend(ResultBits.getLimitedValue()); 5941 Result = Result.shl(Right); 5942 5943 // Print the bit representation of the signed integer as an unsigned 5944 // hexadecimal number. 5945 llvm::SmallString<40> HexResult; 5946 Result.toString(HexResult, 16, /*Signed =*/false, /*Literal =*/true); 5947 5948 // If we are only missing a sign bit, this is less likely to result in actual 5949 // bugs -- if the result is cast back to an unsigned type, it will have the 5950 // expected value. Thus we place this behind a different warning that can be 5951 // turned off separately if needed. 5952 if (LeftBits == ResultBits - 1) { 5953 S.Diag(Loc, diag::warn_shift_result_sets_sign_bit) 5954 << HexResult.str() << LHSTy 5955 << lex.get()->getSourceRange() << rex.get()->getSourceRange(); 5956 return; 5957 } 5958 5959 S.Diag(Loc, diag::warn_shift_result_gt_typewidth) 5960 << HexResult.str() << Result.getMinSignedBits() << LHSTy 5961 << Left.getBitWidth() << lex.get()->getSourceRange() << rex.get()->getSourceRange(); 5962} 5963 5964// C99 6.5.7 5965QualType Sema::CheckShiftOperands(ExprResult &lex, ExprResult &rex, SourceLocation Loc, 5966 unsigned Opc, bool isCompAssign) { 5967 // C99 6.5.7p2: Each of the operands shall have integer type. 5968 if (!lex.get()->getType()->hasIntegerRepresentation() || 5969 !rex.get()->getType()->hasIntegerRepresentation()) 5970 return InvalidOperands(Loc, lex, rex); 5971 5972 // C++0x: Don't allow scoped enums. FIXME: Use something better than 5973 // hasIntegerRepresentation() above instead of this. 5974 if (isScopedEnumerationType(lex.get()->getType()) || 5975 isScopedEnumerationType(rex.get()->getType())) { 5976 return InvalidOperands(Loc, lex, rex); 5977 } 5978 5979 // Vector shifts promote their scalar inputs to vector type. 5980 if (lex.get()->getType()->isVectorType() || rex.get()->getType()->isVectorType()) 5981 return CheckVectorOperands(lex, rex, Loc, isCompAssign); 5982 5983 // Shifts don't perform usual arithmetic conversions, they just do integer 5984 // promotions on each operand. C99 6.5.7p3 5985 5986 // For the LHS, do usual unary conversions, but then reset them away 5987 // if this is a compound assignment. 5988 ExprResult old_lex = lex; 5989 lex = UsualUnaryConversions(lex.take()); 5990 if (lex.isInvalid()) 5991 return QualType(); 5992 QualType LHSTy = lex.get()->getType(); 5993 if (isCompAssign) lex = old_lex; 5994 5995 // The RHS is simpler. 5996 rex = UsualUnaryConversions(rex.take()); 5997 if (rex.isInvalid()) 5998 return QualType(); 5999 6000 // Sanity-check shift operands 6001 DiagnoseBadShiftValues(*this, lex, rex, Loc, Opc, LHSTy); 6002 6003 // "The type of the result is that of the promoted left operand." 6004 return LHSTy; 6005} 6006 6007static bool IsWithinTemplateSpecialization(Decl *D) { 6008 if (DeclContext *DC = D->getDeclContext()) { 6009 if (isa<ClassTemplateSpecializationDecl>(DC)) 6010 return true; 6011 if (FunctionDecl *FD = dyn_cast<FunctionDecl>(DC)) 6012 return FD->isFunctionTemplateSpecialization(); 6013 } 6014 return false; 6015} 6016 6017// C99 6.5.8, C++ [expr.rel] 6018QualType Sema::CheckCompareOperands(ExprResult &lex, ExprResult &rex, SourceLocation Loc, 6019 unsigned OpaqueOpc, bool isRelational) { 6020 BinaryOperatorKind Opc = (BinaryOperatorKind) OpaqueOpc; 6021 6022 // Handle vector comparisons separately. 6023 if (lex.get()->getType()->isVectorType() || rex.get()->getType()->isVectorType()) 6024 return CheckVectorCompareOperands(lex, rex, Loc, isRelational); 6025 6026 QualType lType = lex.get()->getType(); 6027 QualType rType = rex.get()->getType(); 6028 6029 Expr *LHSStripped = lex.get()->IgnoreParenImpCasts(); 6030 Expr *RHSStripped = rex.get()->IgnoreParenImpCasts(); 6031 QualType LHSStrippedType = LHSStripped->getType(); 6032 QualType RHSStrippedType = RHSStripped->getType(); 6033 6034 6035 6036 // Two different enums will raise a warning when compared. 6037 if (const EnumType *LHSEnumType = LHSStrippedType->getAs<EnumType>()) { 6038 if (const EnumType *RHSEnumType = RHSStrippedType->getAs<EnumType>()) { 6039 if (LHSEnumType->getDecl()->getIdentifier() && 6040 RHSEnumType->getDecl()->getIdentifier() && 6041 !Context.hasSameUnqualifiedType(LHSStrippedType, RHSStrippedType)) { 6042 Diag(Loc, diag::warn_comparison_of_mixed_enum_types) 6043 << LHSStrippedType << RHSStrippedType 6044 << lex.get()->getSourceRange() << rex.get()->getSourceRange(); 6045 } 6046 } 6047 } 6048 6049 if (!lType->hasFloatingRepresentation() && 6050 !(lType->isBlockPointerType() && isRelational) && 6051 !lex.get()->getLocStart().isMacroID() && 6052 !rex.get()->getLocStart().isMacroID()) { 6053 // For non-floating point types, check for self-comparisons of the form 6054 // x == x, x != x, x < x, etc. These always evaluate to a constant, and 6055 // often indicate logic errors in the program. 6056 // 6057 // NOTE: Don't warn about comparison expressions resulting from macro 6058 // expansion. Also don't warn about comparisons which are only self 6059 // comparisons within a template specialization. The warnings should catch 6060 // obvious cases in the definition of the template anyways. The idea is to 6061 // warn when the typed comparison operator will always evaluate to the same 6062 // result. 6063 if (DeclRefExpr* DRL = dyn_cast<DeclRefExpr>(LHSStripped)) { 6064 if (DeclRefExpr* DRR = dyn_cast<DeclRefExpr>(RHSStripped)) { 6065 if (DRL->getDecl() == DRR->getDecl() && 6066 !IsWithinTemplateSpecialization(DRL->getDecl())) { 6067 DiagRuntimeBehavior(Loc, 0, PDiag(diag::warn_comparison_always) 6068 << 0 // self- 6069 << (Opc == BO_EQ 6070 || Opc == BO_LE 6071 || Opc == BO_GE)); 6072 } else if (lType->isArrayType() && rType->isArrayType() && 6073 !DRL->getDecl()->getType()->isReferenceType() && 6074 !DRR->getDecl()->getType()->isReferenceType()) { 6075 // what is it always going to eval to? 6076 char always_evals_to; 6077 switch(Opc) { 6078 case BO_EQ: // e.g. array1 == array2 6079 always_evals_to = 0; // false 6080 break; 6081 case BO_NE: // e.g. array1 != array2 6082 always_evals_to = 1; // true 6083 break; 6084 default: 6085 // best we can say is 'a constant' 6086 always_evals_to = 2; // e.g. array1 <= array2 6087 break; 6088 } 6089 DiagRuntimeBehavior(Loc, 0, PDiag(diag::warn_comparison_always) 6090 << 1 // array 6091 << always_evals_to); 6092 } 6093 } 6094 } 6095 6096 if (isa<CastExpr>(LHSStripped)) 6097 LHSStripped = LHSStripped->IgnoreParenCasts(); 6098 if (isa<CastExpr>(RHSStripped)) 6099 RHSStripped = RHSStripped->IgnoreParenCasts(); 6100 6101 // Warn about comparisons against a string constant (unless the other 6102 // operand is null), the user probably wants strcmp. 6103 Expr *literalString = 0; 6104 Expr *literalStringStripped = 0; 6105 if ((isa<StringLiteral>(LHSStripped) || isa<ObjCEncodeExpr>(LHSStripped)) && 6106 !RHSStripped->isNullPointerConstant(Context, 6107 Expr::NPC_ValueDependentIsNull)) { 6108 literalString = lex.get(); 6109 literalStringStripped = LHSStripped; 6110 } else if ((isa<StringLiteral>(RHSStripped) || 6111 isa<ObjCEncodeExpr>(RHSStripped)) && 6112 !LHSStripped->isNullPointerConstant(Context, 6113 Expr::NPC_ValueDependentIsNull)) { 6114 literalString = rex.get(); 6115 literalStringStripped = RHSStripped; 6116 } 6117 6118 if (literalString) { 6119 std::string resultComparison; 6120 switch (Opc) { 6121 case BO_LT: resultComparison = ") < 0"; break; 6122 case BO_GT: resultComparison = ") > 0"; break; 6123 case BO_LE: resultComparison = ") <= 0"; break; 6124 case BO_GE: resultComparison = ") >= 0"; break; 6125 case BO_EQ: resultComparison = ") == 0"; break; 6126 case BO_NE: resultComparison = ") != 0"; break; 6127 default: assert(false && "Invalid comparison operator"); 6128 } 6129 6130 DiagRuntimeBehavior(Loc, 0, 6131 PDiag(diag::warn_stringcompare) 6132 << isa<ObjCEncodeExpr>(literalStringStripped) 6133 << literalString->getSourceRange()); 6134 } 6135 } 6136 6137 // C99 6.5.8p3 / C99 6.5.9p4 6138 if (lex.get()->getType()->isArithmeticType() && rex.get()->getType()->isArithmeticType()) { 6139 UsualArithmeticConversions(lex, rex); 6140 if (lex.isInvalid() || rex.isInvalid()) 6141 return QualType(); 6142 } 6143 else { 6144 lex = UsualUnaryConversions(lex.take()); 6145 if (lex.isInvalid()) 6146 return QualType(); 6147 6148 rex = UsualUnaryConversions(rex.take()); 6149 if (rex.isInvalid()) 6150 return QualType(); 6151 } 6152 6153 lType = lex.get()->getType(); 6154 rType = rex.get()->getType(); 6155 6156 // The result of comparisons is 'bool' in C++, 'int' in C. 6157 QualType ResultTy = Context.getLogicalOperationType(); 6158 6159 if (isRelational) { 6160 if (lType->isRealType() && rType->isRealType()) 6161 return ResultTy; 6162 } else { 6163 // Check for comparisons of floating point operands using != and ==. 6164 if (lType->hasFloatingRepresentation()) 6165 CheckFloatComparison(Loc, lex.get(), rex.get()); 6166 6167 if (lType->isArithmeticType() && rType->isArithmeticType()) 6168 return ResultTy; 6169 } 6170 6171 bool LHSIsNull = lex.get()->isNullPointerConstant(Context, 6172 Expr::NPC_ValueDependentIsNull); 6173 bool RHSIsNull = rex.get()->isNullPointerConstant(Context, 6174 Expr::NPC_ValueDependentIsNull); 6175 6176 // All of the following pointer-related warnings are GCC extensions, except 6177 // when handling null pointer constants. 6178 if (lType->isPointerType() && rType->isPointerType()) { // C99 6.5.8p2 6179 QualType LCanPointeeTy = 6180 Context.getCanonicalType(lType->getAs<PointerType>()->getPointeeType()); 6181 QualType RCanPointeeTy = 6182 Context.getCanonicalType(rType->getAs<PointerType>()->getPointeeType()); 6183 6184 if (getLangOptions().CPlusPlus) { 6185 if (LCanPointeeTy == RCanPointeeTy) 6186 return ResultTy; 6187 if (!isRelational && 6188 (LCanPointeeTy->isVoidType() || RCanPointeeTy->isVoidType())) { 6189 // Valid unless comparison between non-null pointer and function pointer 6190 // This is a gcc extension compatibility comparison. 6191 // In a SFINAE context, we treat this as a hard error to maintain 6192 // conformance with the C++ standard. 6193 if ((LCanPointeeTy->isFunctionType() || RCanPointeeTy->isFunctionType()) 6194 && !LHSIsNull && !RHSIsNull) { 6195 Diag(Loc, 6196 isSFINAEContext()? 6197 diag::err_typecheck_comparison_of_fptr_to_void 6198 : diag::ext_typecheck_comparison_of_fptr_to_void) 6199 << lType << rType << lex.get()->getSourceRange() << rex.get()->getSourceRange(); 6200 6201 if (isSFINAEContext()) 6202 return QualType(); 6203 6204 rex = ImpCastExprToType(rex.take(), lType, CK_BitCast); 6205 return ResultTy; 6206 } 6207 } 6208 6209 // C++ [expr.rel]p2: 6210 // [...] Pointer conversions (4.10) and qualification 6211 // conversions (4.4) are performed on pointer operands (or on 6212 // a pointer operand and a null pointer constant) to bring 6213 // them to their composite pointer type. [...] 6214 // 6215 // C++ [expr.eq]p1 uses the same notion for (in)equality 6216 // comparisons of pointers. 6217 bool NonStandardCompositeType = false; 6218 QualType T = FindCompositePointerType(Loc, lex, rex, 6219 isSFINAEContext()? 0 : &NonStandardCompositeType); 6220 if (T.isNull()) { 6221 Diag(Loc, diag::err_typecheck_comparison_of_distinct_pointers) 6222 << lType << rType << lex.get()->getSourceRange() << rex.get()->getSourceRange(); 6223 return QualType(); 6224 } else if (NonStandardCompositeType) { 6225 Diag(Loc, 6226 diag::ext_typecheck_comparison_of_distinct_pointers_nonstandard) 6227 << lType << rType << T 6228 << lex.get()->getSourceRange() << rex.get()->getSourceRange(); 6229 } 6230 6231 lex = ImpCastExprToType(lex.take(), T, CK_BitCast); 6232 rex = ImpCastExprToType(rex.take(), T, CK_BitCast); 6233 return ResultTy; 6234 } 6235 // C99 6.5.9p2 and C99 6.5.8p2 6236 if (Context.typesAreCompatible(LCanPointeeTy.getUnqualifiedType(), 6237 RCanPointeeTy.getUnqualifiedType())) { 6238 // Valid unless a relational comparison of function pointers 6239 if (isRelational && LCanPointeeTy->isFunctionType()) { 6240 Diag(Loc, diag::ext_typecheck_ordered_comparison_of_function_pointers) 6241 << lType << rType << lex.get()->getSourceRange() << rex.get()->getSourceRange(); 6242 } 6243 } else if (!isRelational && 6244 (LCanPointeeTy->isVoidType() || RCanPointeeTy->isVoidType())) { 6245 // Valid unless comparison between non-null pointer and function pointer 6246 if ((LCanPointeeTy->isFunctionType() || RCanPointeeTy->isFunctionType()) 6247 && !LHSIsNull && !RHSIsNull) { 6248 Diag(Loc, diag::ext_typecheck_comparison_of_fptr_to_void) 6249 << lType << rType << lex.get()->getSourceRange() << rex.get()->getSourceRange(); 6250 } 6251 } else { 6252 // Invalid 6253 Diag(Loc, diag::ext_typecheck_comparison_of_distinct_pointers) 6254 << lType << rType << lex.get()->getSourceRange() << rex.get()->getSourceRange(); 6255 } 6256 if (LCanPointeeTy != RCanPointeeTy) { 6257 if (LHSIsNull && !RHSIsNull) 6258 lex = ImpCastExprToType(lex.take(), rType, CK_BitCast); 6259 else 6260 rex = ImpCastExprToType(rex.take(), lType, CK_BitCast); 6261 } 6262 return ResultTy; 6263 } 6264 6265 if (getLangOptions().CPlusPlus) { 6266 // Comparison of nullptr_t with itself. 6267 if (lType->isNullPtrType() && rType->isNullPtrType()) 6268 return ResultTy; 6269 6270 // Comparison of pointers with null pointer constants and equality 6271 // comparisons of member pointers to null pointer constants. 6272 if (RHSIsNull && 6273 ((lType->isAnyPointerType() || lType->isNullPtrType()) || 6274 (!isRelational && 6275 (lType->isMemberPointerType() || lType->isBlockPointerType())))) { 6276 rex = ImpCastExprToType(rex.take(), lType, 6277 lType->isMemberPointerType() 6278 ? CK_NullToMemberPointer 6279 : CK_NullToPointer); 6280 return ResultTy; 6281 } 6282 if (LHSIsNull && 6283 ((rType->isAnyPointerType() || rType->isNullPtrType()) || 6284 (!isRelational && 6285 (rType->isMemberPointerType() || rType->isBlockPointerType())))) { 6286 lex = ImpCastExprToType(lex.take(), rType, 6287 rType->isMemberPointerType() 6288 ? CK_NullToMemberPointer 6289 : CK_NullToPointer); 6290 return ResultTy; 6291 } 6292 6293 // Comparison of member pointers. 6294 if (!isRelational && 6295 lType->isMemberPointerType() && rType->isMemberPointerType()) { 6296 // C++ [expr.eq]p2: 6297 // In addition, pointers to members can be compared, or a pointer to 6298 // member and a null pointer constant. Pointer to member conversions 6299 // (4.11) and qualification conversions (4.4) are performed to bring 6300 // them to a common type. If one operand is a null pointer constant, 6301 // the common type is the type of the other operand. Otherwise, the 6302 // common type is a pointer to member type similar (4.4) to the type 6303 // of one of the operands, with a cv-qualification signature (4.4) 6304 // that is the union of the cv-qualification signatures of the operand 6305 // types. 6306 bool NonStandardCompositeType = false; 6307 QualType T = FindCompositePointerType(Loc, lex, rex, 6308 isSFINAEContext()? 0 : &NonStandardCompositeType); 6309 if (T.isNull()) { 6310 Diag(Loc, diag::err_typecheck_comparison_of_distinct_pointers) 6311 << lType << rType << lex.get()->getSourceRange() << rex.get()->getSourceRange(); 6312 return QualType(); 6313 } else if (NonStandardCompositeType) { 6314 Diag(Loc, 6315 diag::ext_typecheck_comparison_of_distinct_pointers_nonstandard) 6316 << lType << rType << T 6317 << lex.get()->getSourceRange() << rex.get()->getSourceRange(); 6318 } 6319 6320 lex = ImpCastExprToType(lex.take(), T, CK_BitCast); 6321 rex = ImpCastExprToType(rex.take(), T, CK_BitCast); 6322 return ResultTy; 6323 } 6324 6325 // Handle scoped enumeration types specifically, since they don't promote 6326 // to integers. 6327 if (lex.get()->getType()->isEnumeralType() && 6328 Context.hasSameUnqualifiedType(lex.get()->getType(), rex.get()->getType())) 6329 return ResultTy; 6330 } 6331 6332 // Handle block pointer types. 6333 if (!isRelational && lType->isBlockPointerType() && rType->isBlockPointerType()) { 6334 QualType lpointee = lType->getAs<BlockPointerType>()->getPointeeType(); 6335 QualType rpointee = rType->getAs<BlockPointerType>()->getPointeeType(); 6336 6337 if (!LHSIsNull && !RHSIsNull && 6338 !Context.typesAreCompatible(lpointee, rpointee)) { 6339 Diag(Loc, diag::err_typecheck_comparison_of_distinct_blocks) 6340 << lType << rType << lex.get()->getSourceRange() << rex.get()->getSourceRange(); 6341 } 6342 rex = ImpCastExprToType(rex.take(), lType, CK_BitCast); 6343 return ResultTy; 6344 } 6345 6346 // Allow block pointers to be compared with null pointer constants. 6347 if (!isRelational 6348 && ((lType->isBlockPointerType() && rType->isPointerType()) 6349 || (lType->isPointerType() && rType->isBlockPointerType()))) { 6350 if (!LHSIsNull && !RHSIsNull) { 6351 if (!((rType->isPointerType() && rType->castAs<PointerType>() 6352 ->getPointeeType()->isVoidType()) 6353 || (lType->isPointerType() && lType->castAs<PointerType>() 6354 ->getPointeeType()->isVoidType()))) 6355 Diag(Loc, diag::err_typecheck_comparison_of_distinct_blocks) 6356 << lType << rType << lex.get()->getSourceRange() << rex.get()->getSourceRange(); 6357 } 6358 if (LHSIsNull && !RHSIsNull) 6359 lex = ImpCastExprToType(lex.take(), rType, CK_BitCast); 6360 else 6361 rex = ImpCastExprToType(rex.take(), lType, CK_BitCast); 6362 return ResultTy; 6363 } 6364 6365 if (lType->isObjCObjectPointerType() || rType->isObjCObjectPointerType()) { 6366 const PointerType *LPT = lType->getAs<PointerType>(); 6367 const PointerType *RPT = rType->getAs<PointerType>(); 6368 if (LPT || RPT) { 6369 bool LPtrToVoid = LPT ? LPT->getPointeeType()->isVoidType() : false; 6370 bool RPtrToVoid = RPT ? RPT->getPointeeType()->isVoidType() : false; 6371 6372 if (!LPtrToVoid && !RPtrToVoid && 6373 !Context.typesAreCompatible(lType, rType)) { 6374 Diag(Loc, diag::ext_typecheck_comparison_of_distinct_pointers) 6375 << lType << rType << lex.get()->getSourceRange() << rex.get()->getSourceRange(); 6376 } 6377 if (LHSIsNull && !RHSIsNull) 6378 lex = ImpCastExprToType(lex.take(), rType, CK_BitCast); 6379 else 6380 rex = ImpCastExprToType(rex.take(), lType, CK_BitCast); 6381 return ResultTy; 6382 } 6383 if (lType->isObjCObjectPointerType() && rType->isObjCObjectPointerType()) { 6384 if (!Context.areComparableObjCPointerTypes(lType, rType)) 6385 Diag(Loc, diag::ext_typecheck_comparison_of_distinct_pointers) 6386 << lType << rType << lex.get()->getSourceRange() << rex.get()->getSourceRange(); 6387 if (LHSIsNull && !RHSIsNull) 6388 lex = ImpCastExprToType(lex.take(), rType, CK_BitCast); 6389 else 6390 rex = ImpCastExprToType(rex.take(), lType, CK_BitCast); 6391 return ResultTy; 6392 } 6393 } 6394 if ((lType->isAnyPointerType() && rType->isIntegerType()) || 6395 (lType->isIntegerType() && rType->isAnyPointerType())) { 6396 unsigned DiagID = 0; 6397 bool isError = false; 6398 if ((LHSIsNull && lType->isIntegerType()) || 6399 (RHSIsNull && rType->isIntegerType())) { 6400 if (isRelational && !getLangOptions().CPlusPlus) 6401 DiagID = diag::ext_typecheck_ordered_comparison_of_pointer_and_zero; 6402 } else if (isRelational && !getLangOptions().CPlusPlus) 6403 DiagID = diag::ext_typecheck_ordered_comparison_of_pointer_integer; 6404 else if (getLangOptions().CPlusPlus) { 6405 DiagID = diag::err_typecheck_comparison_of_pointer_integer; 6406 isError = true; 6407 } else 6408 DiagID = diag::ext_typecheck_comparison_of_pointer_integer; 6409 6410 if (DiagID) { 6411 Diag(Loc, DiagID) 6412 << lType << rType << lex.get()->getSourceRange() << rex.get()->getSourceRange(); 6413 if (isError) 6414 return QualType(); 6415 } 6416 6417 if (lType->isIntegerType()) 6418 lex = ImpCastExprToType(lex.take(), rType, 6419 LHSIsNull ? CK_NullToPointer : CK_IntegralToPointer); 6420 else 6421 rex = ImpCastExprToType(rex.take(), lType, 6422 RHSIsNull ? CK_NullToPointer : CK_IntegralToPointer); 6423 return ResultTy; 6424 } 6425 6426 // Handle block pointers. 6427 if (!isRelational && RHSIsNull 6428 && lType->isBlockPointerType() && rType->isIntegerType()) { 6429 rex = ImpCastExprToType(rex.take(), lType, CK_NullToPointer); 6430 return ResultTy; 6431 } 6432 if (!isRelational && LHSIsNull 6433 && lType->isIntegerType() && rType->isBlockPointerType()) { 6434 lex = ImpCastExprToType(lex.take(), rType, CK_NullToPointer); 6435 return ResultTy; 6436 } 6437 6438 return InvalidOperands(Loc, lex, rex); 6439} 6440 6441/// CheckVectorCompareOperands - vector comparisons are a clang extension that 6442/// operates on extended vector types. Instead of producing an IntTy result, 6443/// like a scalar comparison, a vector comparison produces a vector of integer 6444/// types. 6445QualType Sema::CheckVectorCompareOperands(ExprResult &lex, ExprResult &rex, 6446 SourceLocation Loc, 6447 bool isRelational) { 6448 // Check to make sure we're operating on vectors of the same type and width, 6449 // Allowing one side to be a scalar of element type. 6450 QualType vType = CheckVectorOperands(lex, rex, Loc, /*isCompAssign*/false); 6451 if (vType.isNull()) 6452 return vType; 6453 6454 QualType lType = lex.get()->getType(); 6455 QualType rType = rex.get()->getType(); 6456 6457 // If AltiVec, the comparison results in a numeric type, i.e. 6458 // bool for C++, int for C 6459 if (vType->getAs<VectorType>()->getVectorKind() == VectorType::AltiVecVector) 6460 return Context.getLogicalOperationType(); 6461 6462 // For non-floating point types, check for self-comparisons of the form 6463 // x == x, x != x, x < x, etc. These always evaluate to a constant, and 6464 // often indicate logic errors in the program. 6465 if (!lType->hasFloatingRepresentation()) { 6466 if (DeclRefExpr* DRL = dyn_cast<DeclRefExpr>(lex.get()->IgnoreParens())) 6467 if (DeclRefExpr* DRR = dyn_cast<DeclRefExpr>(rex.get()->IgnoreParens())) 6468 if (DRL->getDecl() == DRR->getDecl()) 6469 DiagRuntimeBehavior(Loc, 0, 6470 PDiag(diag::warn_comparison_always) 6471 << 0 // self- 6472 << 2 // "a constant" 6473 ); 6474 } 6475 6476 // Check for comparisons of floating point operands using != and ==. 6477 if (!isRelational && lType->hasFloatingRepresentation()) { 6478 assert (rType->hasFloatingRepresentation()); 6479 CheckFloatComparison(Loc, lex.get(), rex.get()); 6480 } 6481 6482 // Return the type for the comparison, which is the same as vector type for 6483 // integer vectors, or an integer type of identical size and number of 6484 // elements for floating point vectors. 6485 if (lType->hasIntegerRepresentation()) 6486 return lType; 6487 6488 const VectorType *VTy = lType->getAs<VectorType>(); 6489 unsigned TypeSize = Context.getTypeSize(VTy->getElementType()); 6490 if (TypeSize == Context.getTypeSize(Context.IntTy)) 6491 return Context.getExtVectorType(Context.IntTy, VTy->getNumElements()); 6492 if (TypeSize == Context.getTypeSize(Context.LongTy)) 6493 return Context.getExtVectorType(Context.LongTy, VTy->getNumElements()); 6494 6495 assert(TypeSize == Context.getTypeSize(Context.LongLongTy) && 6496 "Unhandled vector element size in vector compare"); 6497 return Context.getExtVectorType(Context.LongLongTy, VTy->getNumElements()); 6498} 6499 6500inline QualType Sema::CheckBitwiseOperands( 6501 ExprResult &lex, ExprResult &rex, SourceLocation Loc, bool isCompAssign) { 6502 if (lex.get()->getType()->isVectorType() || rex.get()->getType()->isVectorType()) { 6503 if (lex.get()->getType()->hasIntegerRepresentation() && 6504 rex.get()->getType()->hasIntegerRepresentation()) 6505 return CheckVectorOperands(lex, rex, Loc, isCompAssign); 6506 6507 return InvalidOperands(Loc, lex, rex); 6508 } 6509 6510 ExprResult lexResult = Owned(lex), rexResult = Owned(rex); 6511 QualType compType = UsualArithmeticConversions(lexResult, rexResult, isCompAssign); 6512 if (lexResult.isInvalid() || rexResult.isInvalid()) 6513 return QualType(); 6514 lex = lexResult.take(); 6515 rex = rexResult.take(); 6516 6517 if (lex.get()->getType()->isIntegralOrUnscopedEnumerationType() && 6518 rex.get()->getType()->isIntegralOrUnscopedEnumerationType()) 6519 return compType; 6520 return InvalidOperands(Loc, lex, rex); 6521} 6522 6523inline QualType Sema::CheckLogicalOperands( // C99 6.5.[13,14] 6524 ExprResult &lex, ExprResult &rex, SourceLocation Loc, unsigned Opc) { 6525 6526 // Diagnose cases where the user write a logical and/or but probably meant a 6527 // bitwise one. We do this when the LHS is a non-bool integer and the RHS 6528 // is a constant. 6529 if (lex.get()->getType()->isIntegerType() && !lex.get()->getType()->isBooleanType() && 6530 rex.get()->getType()->isIntegerType() && !rex.get()->isValueDependent() && 6531 // Don't warn in macros. 6532 !Loc.isMacroID()) { 6533 // If the RHS can be constant folded, and if it constant folds to something 6534 // that isn't 0 or 1 (which indicate a potential logical operation that 6535 // happened to fold to true/false) then warn. 6536 // Parens on the RHS are ignored. 6537 Expr::EvalResult Result; 6538 if (rex.get()->Evaluate(Result, Context) && !Result.HasSideEffects) 6539 if ((getLangOptions().Bool && !rex.get()->getType()->isBooleanType()) || 6540 (Result.Val.getInt() != 0 && Result.Val.getInt() != 1)) { 6541 Diag(Loc, diag::warn_logical_instead_of_bitwise) 6542 << rex.get()->getSourceRange() 6543 << (Opc == BO_LAnd ? "&&" : "||") 6544 << (Opc == BO_LAnd ? "&" : "|"); 6545 } 6546 } 6547 6548 if (!Context.getLangOptions().CPlusPlus) { 6549 lex = UsualUnaryConversions(lex.take()); 6550 if (lex.isInvalid()) 6551 return QualType(); 6552 6553 rex = UsualUnaryConversions(rex.take()); 6554 if (rex.isInvalid()) 6555 return QualType(); 6556 6557 if (!lex.get()->getType()->isScalarType() || !rex.get()->getType()->isScalarType()) 6558 return InvalidOperands(Loc, lex, rex); 6559 6560 return Context.IntTy; 6561 } 6562 6563 // The following is safe because we only use this method for 6564 // non-overloadable operands. 6565 6566 // C++ [expr.log.and]p1 6567 // C++ [expr.log.or]p1 6568 // The operands are both contextually converted to type bool. 6569 ExprResult lexRes = PerformContextuallyConvertToBool(lex.get()); 6570 if (lexRes.isInvalid()) 6571 return InvalidOperands(Loc, lex, rex); 6572 lex = move(lexRes); 6573 6574 ExprResult rexRes = PerformContextuallyConvertToBool(rex.get()); 6575 if (rexRes.isInvalid()) 6576 return InvalidOperands(Loc, lex, rex); 6577 rex = move(rexRes); 6578 6579 // C++ [expr.log.and]p2 6580 // C++ [expr.log.or]p2 6581 // The result is a bool. 6582 return Context.BoolTy; 6583} 6584 6585/// IsReadonlyProperty - Verify that otherwise a valid l-value expression 6586/// is a read-only property; return true if so. A readonly property expression 6587/// depends on various declarations and thus must be treated specially. 6588/// 6589static bool IsReadonlyProperty(Expr *E, Sema &S) { 6590 if (E->getStmtClass() == Expr::ObjCPropertyRefExprClass) { 6591 const ObjCPropertyRefExpr* PropExpr = cast<ObjCPropertyRefExpr>(E); 6592 if (PropExpr->isImplicitProperty()) return false; 6593 6594 ObjCPropertyDecl *PDecl = PropExpr->getExplicitProperty(); 6595 QualType BaseType = PropExpr->isSuperReceiver() ? 6596 PropExpr->getSuperReceiverType() : 6597 PropExpr->getBase()->getType(); 6598 6599 if (const ObjCObjectPointerType *OPT = 6600 BaseType->getAsObjCInterfacePointerType()) 6601 if (ObjCInterfaceDecl *IFace = OPT->getInterfaceDecl()) 6602 if (S.isPropertyReadonly(PDecl, IFace)) 6603 return true; 6604 } 6605 return false; 6606} 6607 6608static bool IsConstProperty(Expr *E, Sema &S) { 6609 if (E->getStmtClass() == Expr::ObjCPropertyRefExprClass) { 6610 const ObjCPropertyRefExpr* PropExpr = cast<ObjCPropertyRefExpr>(E); 6611 if (PropExpr->isImplicitProperty()) return false; 6612 6613 ObjCPropertyDecl *PDecl = PropExpr->getExplicitProperty(); 6614 QualType T = PDecl->getType(); 6615 if (T->isReferenceType()) 6616 T = T->getAs<ReferenceType>()->getPointeeType(); 6617 CanQualType CT = S.Context.getCanonicalType(T); 6618 return CT.isConstQualified(); 6619 } 6620 return false; 6621} 6622 6623static bool IsReadonlyMessage(Expr *E, Sema &S) { 6624 if (E->getStmtClass() != Expr::MemberExprClass) 6625 return false; 6626 const MemberExpr *ME = cast<MemberExpr>(E); 6627 NamedDecl *Member = ME->getMemberDecl(); 6628 if (isa<FieldDecl>(Member)) { 6629 Expr *Base = ME->getBase()->IgnoreParenImpCasts(); 6630 if (Base->getStmtClass() != Expr::ObjCMessageExprClass) 6631 return false; 6632 return cast<ObjCMessageExpr>(Base)->getMethodDecl() != 0; 6633 } 6634 return false; 6635} 6636 6637/// CheckForModifiableLvalue - Verify that E is a modifiable lvalue. If not, 6638/// emit an error and return true. If so, return false. 6639static bool CheckForModifiableLvalue(Expr *E, SourceLocation Loc, Sema &S) { 6640 SourceLocation OrigLoc = Loc; 6641 Expr::isModifiableLvalueResult IsLV = E->isModifiableLvalue(S.Context, 6642 &Loc); 6643 if (IsLV == Expr::MLV_Valid && IsReadonlyProperty(E, S)) 6644 IsLV = Expr::MLV_ReadonlyProperty; 6645 else if (Expr::MLV_ConstQualified && IsConstProperty(E, S)) 6646 IsLV = Expr::MLV_Valid; 6647 else if (IsLV == Expr::MLV_ClassTemporary && IsReadonlyMessage(E, S)) 6648 IsLV = Expr::MLV_InvalidMessageExpression; 6649 if (IsLV == Expr::MLV_Valid) 6650 return false; 6651 6652 unsigned Diag = 0; 6653 bool NeedType = false; 6654 switch (IsLV) { // C99 6.5.16p2 6655 case Expr::MLV_ConstQualified: 6656 Diag = diag::err_typecheck_assign_const; 6657 6658 // In ARC, use some specialized diagnostics for occasions where we 6659 // infer 'const'. These are always pseudo-strong variables. 6660 if (S.getLangOptions().ObjCAutoRefCount) { 6661 DeclRefExpr *declRef = dyn_cast<DeclRefExpr>(E->IgnoreParenCasts()); 6662 if (declRef && isa<VarDecl>(declRef->getDecl())) { 6663 VarDecl *var = cast<VarDecl>(declRef->getDecl()); 6664 6665 // Use the normal diagnostic if it's pseudo-__strong but the 6666 // user actually wrote 'const'. 6667 if (var->isARCPseudoStrong() && 6668 (!var->getTypeSourceInfo() || 6669 !var->getTypeSourceInfo()->getType().isConstQualified())) { 6670 // There are two pseudo-strong cases: 6671 // - self 6672 ObjCMethodDecl *method = S.getCurMethodDecl(); 6673 if (method && var == method->getSelfDecl()) 6674 Diag = diag::err_typecheck_arr_assign_self; 6675 6676 // - fast enumeration variables 6677 else 6678 Diag = diag::err_typecheck_arr_assign_enumeration; 6679 6680 SourceRange Assign; 6681 if (Loc != OrigLoc) 6682 Assign = SourceRange(OrigLoc, OrigLoc); 6683 S.Diag(Loc, Diag) << E->getSourceRange() << Assign; 6684 // We need to preserve the AST regardless, so migration tool 6685 // can do its job. 6686 return false; 6687 } 6688 } 6689 } 6690 6691 break; 6692 case Expr::MLV_ArrayType: 6693 Diag = diag::err_typecheck_array_not_modifiable_lvalue; 6694 NeedType = true; 6695 break; 6696 case Expr::MLV_NotObjectType: 6697 Diag = diag::err_typecheck_non_object_not_modifiable_lvalue; 6698 NeedType = true; 6699 break; 6700 case Expr::MLV_LValueCast: 6701 Diag = diag::err_typecheck_lvalue_casts_not_supported; 6702 break; 6703 case Expr::MLV_Valid: 6704 llvm_unreachable("did not take early return for MLV_Valid"); 6705 case Expr::MLV_InvalidExpression: 6706 case Expr::MLV_MemberFunction: 6707 case Expr::MLV_ClassTemporary: 6708 Diag = diag::err_typecheck_expression_not_modifiable_lvalue; 6709 break; 6710 case Expr::MLV_IncompleteType: 6711 case Expr::MLV_IncompleteVoidType: 6712 return S.RequireCompleteType(Loc, E->getType(), 6713 S.PDiag(diag::err_typecheck_incomplete_type_not_modifiable_lvalue) 6714 << E->getSourceRange()); 6715 case Expr::MLV_DuplicateVectorComponents: 6716 Diag = diag::err_typecheck_duplicate_vector_components_not_mlvalue; 6717 break; 6718 case Expr::MLV_NotBlockQualified: 6719 Diag = diag::err_block_decl_ref_not_modifiable_lvalue; 6720 break; 6721 case Expr::MLV_ReadonlyProperty: 6722 Diag = diag::error_readonly_property_assignment; 6723 break; 6724 case Expr::MLV_NoSetterProperty: 6725 Diag = diag::error_nosetter_property_assignment; 6726 break; 6727 case Expr::MLV_InvalidMessageExpression: 6728 Diag = diag::error_readonly_message_assignment; 6729 break; 6730 case Expr::MLV_SubObjCPropertySetting: 6731 Diag = diag::error_no_subobject_property_setting; 6732 break; 6733 } 6734 6735 SourceRange Assign; 6736 if (Loc != OrigLoc) 6737 Assign = SourceRange(OrigLoc, OrigLoc); 6738 if (NeedType) 6739 S.Diag(Loc, Diag) << E->getType() << E->getSourceRange() << Assign; 6740 else 6741 S.Diag(Loc, Diag) << E->getSourceRange() << Assign; 6742 return true; 6743} 6744 6745 6746 6747// C99 6.5.16.1 6748QualType Sema::CheckAssignmentOperands(Expr *LHS, ExprResult &RHS, 6749 SourceLocation Loc, 6750 QualType CompoundType) { 6751 // Verify that LHS is a modifiable lvalue, and emit error if not. 6752 if (CheckForModifiableLvalue(LHS, Loc, *this)) 6753 return QualType(); 6754 6755 QualType LHSType = LHS->getType(); 6756 QualType RHSType = CompoundType.isNull() ? RHS.get()->getType() : CompoundType; 6757 AssignConvertType ConvTy; 6758 if (CompoundType.isNull()) { 6759 QualType LHSTy(LHSType); 6760 // Simple assignment "x = y". 6761 if (LHS->getObjectKind() == OK_ObjCProperty) { 6762 ExprResult LHSResult = Owned(LHS); 6763 ConvertPropertyForLValue(LHSResult, RHS, LHSTy); 6764 if (LHSResult.isInvalid()) 6765 return QualType(); 6766 LHS = LHSResult.take(); 6767 } 6768 ConvTy = CheckSingleAssignmentConstraints(LHSTy, RHS); 6769 if (RHS.isInvalid()) 6770 return QualType(); 6771 // Special case of NSObject attributes on c-style pointer types. 6772 if (ConvTy == IncompatiblePointer && 6773 ((Context.isObjCNSObjectType(LHSType) && 6774 RHSType->isObjCObjectPointerType()) || 6775 (Context.isObjCNSObjectType(RHSType) && 6776 LHSType->isObjCObjectPointerType()))) 6777 ConvTy = Compatible; 6778 6779 if (ConvTy == Compatible && 6780 getLangOptions().ObjCNonFragileABI && 6781 LHSType->isObjCObjectType()) 6782 Diag(Loc, diag::err_assignment_requires_nonfragile_object) 6783 << LHSType; 6784 6785 // If the RHS is a unary plus or minus, check to see if they = and + are 6786 // right next to each other. If so, the user may have typo'd "x =+ 4" 6787 // instead of "x += 4". 6788 Expr *RHSCheck = RHS.get(); 6789 if (ImplicitCastExpr *ICE = dyn_cast<ImplicitCastExpr>(RHSCheck)) 6790 RHSCheck = ICE->getSubExpr(); 6791 if (UnaryOperator *UO = dyn_cast<UnaryOperator>(RHSCheck)) { 6792 if ((UO->getOpcode() == UO_Plus || 6793 UO->getOpcode() == UO_Minus) && 6794 Loc.isFileID() && UO->getOperatorLoc().isFileID() && 6795 // Only if the two operators are exactly adjacent. 6796 Loc.getFileLocWithOffset(1) == UO->getOperatorLoc() && 6797 // And there is a space or other character before the subexpr of the 6798 // unary +/-. We don't want to warn on "x=-1". 6799 Loc.getFileLocWithOffset(2) != UO->getSubExpr()->getLocStart() && 6800 UO->getSubExpr()->getLocStart().isFileID()) { 6801 Diag(Loc, diag::warn_not_compound_assign) 6802 << (UO->getOpcode() == UO_Plus ? "+" : "-") 6803 << SourceRange(UO->getOperatorLoc(), UO->getOperatorLoc()); 6804 } 6805 } 6806 6807 if (ConvTy == Compatible) { 6808 if (LHSType.getObjCLifetime() == Qualifiers::OCL_Strong) 6809 checkRetainCycles(LHS, RHS.get()); 6810 else if (getLangOptions().ObjCAutoRefCount) 6811 checkUnsafeExprAssigns(Loc, LHS, RHS.get()); 6812 } 6813 } else { 6814 // Compound assignment "x += y" 6815 ConvTy = CheckAssignmentConstraints(Loc, LHSType, RHSType); 6816 } 6817 6818 if (DiagnoseAssignmentResult(ConvTy, Loc, LHSType, RHSType, 6819 RHS.get(), AA_Assigning)) 6820 return QualType(); 6821 6822 CheckForNullPointerDereference(*this, LHS); 6823 // Check for trivial buffer overflows. 6824 CheckArrayAccess(LHS->IgnoreParenCasts()); 6825 6826 // C99 6.5.16p3: The type of an assignment expression is the type of the 6827 // left operand unless the left operand has qualified type, in which case 6828 // it is the unqualified version of the type of the left operand. 6829 // C99 6.5.16.1p2: In simple assignment, the value of the right operand 6830 // is converted to the type of the assignment expression (above). 6831 // C++ 5.17p1: the type of the assignment expression is that of its left 6832 // operand. 6833 return (getLangOptions().CPlusPlus 6834 ? LHSType : LHSType.getUnqualifiedType()); 6835} 6836 6837// C99 6.5.17 6838static QualType CheckCommaOperands(Sema &S, ExprResult &LHS, ExprResult &RHS, 6839 SourceLocation Loc) { 6840 S.DiagnoseUnusedExprResult(LHS.get()); 6841 6842 LHS = S.CheckPlaceholderExpr(LHS.take()); 6843 RHS = S.CheckPlaceholderExpr(RHS.take()); 6844 if (LHS.isInvalid() || RHS.isInvalid()) 6845 return QualType(); 6846 6847 // C's comma performs lvalue conversion (C99 6.3.2.1) on both its 6848 // operands, but not unary promotions. 6849 // C++'s comma does not do any conversions at all (C++ [expr.comma]p1). 6850 6851 // So we treat the LHS as a ignored value, and in C++ we allow the 6852 // containing site to determine what should be done with the RHS. 6853 LHS = S.IgnoredValueConversions(LHS.take()); 6854 if (LHS.isInvalid()) 6855 return QualType(); 6856 6857 if (!S.getLangOptions().CPlusPlus) { 6858 RHS = S.DefaultFunctionArrayLvalueConversion(RHS.take()); 6859 if (RHS.isInvalid()) 6860 return QualType(); 6861 if (!RHS.get()->getType()->isVoidType()) 6862 S.RequireCompleteType(Loc, RHS.get()->getType(), diag::err_incomplete_type); 6863 } 6864 6865 return RHS.get()->getType(); 6866} 6867 6868/// CheckIncrementDecrementOperand - unlike most "Check" methods, this routine 6869/// doesn't need to call UsualUnaryConversions or UsualArithmeticConversions. 6870static QualType CheckIncrementDecrementOperand(Sema &S, Expr *Op, 6871 ExprValueKind &VK, 6872 SourceLocation OpLoc, 6873 bool isInc, bool isPrefix) { 6874 if (Op->isTypeDependent()) 6875 return S.Context.DependentTy; 6876 6877 QualType ResType = Op->getType(); 6878 assert(!ResType.isNull() && "no type for increment/decrement expression"); 6879 6880 if (S.getLangOptions().CPlusPlus && ResType->isBooleanType()) { 6881 // Decrement of bool is not allowed. 6882 if (!isInc) { 6883 S.Diag(OpLoc, diag::err_decrement_bool) << Op->getSourceRange(); 6884 return QualType(); 6885 } 6886 // Increment of bool sets it to true, but is deprecated. 6887 S.Diag(OpLoc, diag::warn_increment_bool) << Op->getSourceRange(); 6888 } else if (ResType->isRealType()) { 6889 // OK! 6890 } else if (ResType->isAnyPointerType()) { 6891 QualType PointeeTy = ResType->getPointeeType(); 6892 6893 // C99 6.5.2.4p2, 6.5.6p2 6894 if (!checkArithmeticOpPointerOperand(S, OpLoc, Op)) 6895 return QualType(); 6896 6897 // Diagnose bad cases where we step over interface counts. 6898 else if (PointeeTy->isObjCObjectType() && S.LangOpts.ObjCNonFragileABI) { 6899 S.Diag(OpLoc, diag::err_arithmetic_nonfragile_interface) 6900 << PointeeTy << Op->getSourceRange(); 6901 return QualType(); 6902 } 6903 } else if (ResType->isAnyComplexType()) { 6904 // C99 does not support ++/-- on complex types, we allow as an extension. 6905 S.Diag(OpLoc, diag::ext_integer_increment_complex) 6906 << ResType << Op->getSourceRange(); 6907 } else if (ResType->isPlaceholderType()) { 6908 ExprResult PR = S.CheckPlaceholderExpr(Op); 6909 if (PR.isInvalid()) return QualType(); 6910 return CheckIncrementDecrementOperand(S, PR.take(), VK, OpLoc, 6911 isInc, isPrefix); 6912 } else if (S.getLangOptions().AltiVec && ResType->isVectorType()) { 6913 // OK! ( C/C++ Language Extensions for CBEA(Version 2.6) 10.3 ) 6914 } else { 6915 S.Diag(OpLoc, diag::err_typecheck_illegal_increment_decrement) 6916 << ResType << int(isInc) << Op->getSourceRange(); 6917 return QualType(); 6918 } 6919 // At this point, we know we have a real, complex or pointer type. 6920 // Now make sure the operand is a modifiable lvalue. 6921 if (CheckForModifiableLvalue(Op, OpLoc, S)) 6922 return QualType(); 6923 // In C++, a prefix increment is the same type as the operand. Otherwise 6924 // (in C or with postfix), the increment is the unqualified type of the 6925 // operand. 6926 if (isPrefix && S.getLangOptions().CPlusPlus) { 6927 VK = VK_LValue; 6928 return ResType; 6929 } else { 6930 VK = VK_RValue; 6931 return ResType.getUnqualifiedType(); 6932 } 6933} 6934 6935ExprResult Sema::ConvertPropertyForRValue(Expr *E) { 6936 assert(E->getValueKind() == VK_LValue && 6937 E->getObjectKind() == OK_ObjCProperty); 6938 const ObjCPropertyRefExpr *PRE = E->getObjCProperty(); 6939 6940 QualType T = E->getType(); 6941 QualType ReceiverType; 6942 if (PRE->isObjectReceiver()) 6943 ReceiverType = PRE->getBase()->getType(); 6944 else if (PRE->isSuperReceiver()) 6945 ReceiverType = PRE->getSuperReceiverType(); 6946 else 6947 ReceiverType = Context.getObjCInterfaceType(PRE->getClassReceiver()); 6948 6949 ExprValueKind VK = VK_RValue; 6950 if (PRE->isImplicitProperty()) { 6951 if (ObjCMethodDecl *GetterMethod = 6952 PRE->getImplicitPropertyGetter()) { 6953 T = getMessageSendResultType(ReceiverType, GetterMethod, 6954 PRE->isClassReceiver(), 6955 PRE->isSuperReceiver()); 6956 VK = Expr::getValueKindForType(GetterMethod->getResultType()); 6957 } 6958 else { 6959 Diag(PRE->getLocation(), diag::err_getter_not_found) 6960 << PRE->getBase()->getType(); 6961 } 6962 } 6963 6964 E = ImplicitCastExpr::Create(Context, T, CK_GetObjCProperty, 6965 E, 0, VK); 6966 6967 ExprResult Result = MaybeBindToTemporary(E); 6968 if (!Result.isInvalid()) 6969 E = Result.take(); 6970 6971 return Owned(E); 6972} 6973 6974void Sema::ConvertPropertyForLValue(ExprResult &LHS, ExprResult &RHS, QualType &LHSTy) { 6975 assert(LHS.get()->getValueKind() == VK_LValue && 6976 LHS.get()->getObjectKind() == OK_ObjCProperty); 6977 const ObjCPropertyRefExpr *PropRef = LHS.get()->getObjCProperty(); 6978 6979 bool Consumed = false; 6980 6981 if (PropRef->isImplicitProperty()) { 6982 // If using property-dot syntax notation for assignment, and there is a 6983 // setter, RHS expression is being passed to the setter argument. So, 6984 // type conversion (and comparison) is RHS to setter's argument type. 6985 if (const ObjCMethodDecl *SetterMD = PropRef->getImplicitPropertySetter()) { 6986 ObjCMethodDecl::param_iterator P = SetterMD->param_begin(); 6987 LHSTy = (*P)->getType(); 6988 Consumed = (getLangOptions().ObjCAutoRefCount && 6989 (*P)->hasAttr<NSConsumedAttr>()); 6990 6991 // Otherwise, if the getter returns an l-value, just call that. 6992 } else { 6993 QualType Result = PropRef->getImplicitPropertyGetter()->getResultType(); 6994 ExprValueKind VK = Expr::getValueKindForType(Result); 6995 if (VK == VK_LValue) { 6996 LHS = ImplicitCastExpr::Create(Context, LHS.get()->getType(), 6997 CK_GetObjCProperty, LHS.take(), 0, VK); 6998 return; 6999 } 7000 } 7001 } else if (getLangOptions().ObjCAutoRefCount) { 7002 const ObjCMethodDecl *setter 7003 = PropRef->getExplicitProperty()->getSetterMethodDecl(); 7004 if (setter) { 7005 ObjCMethodDecl::param_iterator P = setter->param_begin(); 7006 LHSTy = (*P)->getType(); 7007 Consumed = (*P)->hasAttr<NSConsumedAttr>(); 7008 } 7009 } 7010 7011 if ((getLangOptions().CPlusPlus && LHSTy->isRecordType()) || 7012 getLangOptions().ObjCAutoRefCount) { 7013 InitializedEntity Entity = 7014 InitializedEntity::InitializeParameter(Context, LHSTy, Consumed); 7015 ExprResult ArgE = PerformCopyInitialization(Entity, SourceLocation(), RHS); 7016 if (!ArgE.isInvalid()) { 7017 RHS = ArgE; 7018 if (getLangOptions().ObjCAutoRefCount && !PropRef->isSuperReceiver()) 7019 checkRetainCycles(const_cast<Expr*>(PropRef->getBase()), RHS.get()); 7020 } 7021 } 7022} 7023 7024 7025/// getPrimaryDecl - Helper function for CheckAddressOfOperand(). 7026/// This routine allows us to typecheck complex/recursive expressions 7027/// where the declaration is needed for type checking. We only need to 7028/// handle cases when the expression references a function designator 7029/// or is an lvalue. Here are some examples: 7030/// - &(x) => x 7031/// - &*****f => f for f a function designator. 7032/// - &s.xx => s 7033/// - &s.zz[1].yy -> s, if zz is an array 7034/// - *(x + 1) -> x, if x is an array 7035/// - &"123"[2] -> 0 7036/// - & __real__ x -> x 7037static ValueDecl *getPrimaryDecl(Expr *E) { 7038 switch (E->getStmtClass()) { 7039 case Stmt::DeclRefExprClass: 7040 return cast<DeclRefExpr>(E)->getDecl(); 7041 case Stmt::MemberExprClass: 7042 // If this is an arrow operator, the address is an offset from 7043 // the base's value, so the object the base refers to is 7044 // irrelevant. 7045 if (cast<MemberExpr>(E)->isArrow()) 7046 return 0; 7047 // Otherwise, the expression refers to a part of the base 7048 return getPrimaryDecl(cast<MemberExpr>(E)->getBase()); 7049 case Stmt::ArraySubscriptExprClass: { 7050 // FIXME: This code shouldn't be necessary! We should catch the implicit 7051 // promotion of register arrays earlier. 7052 Expr* Base = cast<ArraySubscriptExpr>(E)->getBase(); 7053 if (ImplicitCastExpr* ICE = dyn_cast<ImplicitCastExpr>(Base)) { 7054 if (ICE->getSubExpr()->getType()->isArrayType()) 7055 return getPrimaryDecl(ICE->getSubExpr()); 7056 } 7057 return 0; 7058 } 7059 case Stmt::UnaryOperatorClass: { 7060 UnaryOperator *UO = cast<UnaryOperator>(E); 7061 7062 switch(UO->getOpcode()) { 7063 case UO_Real: 7064 case UO_Imag: 7065 case UO_Extension: 7066 return getPrimaryDecl(UO->getSubExpr()); 7067 default: 7068 return 0; 7069 } 7070 } 7071 case Stmt::ParenExprClass: 7072 return getPrimaryDecl(cast<ParenExpr>(E)->getSubExpr()); 7073 case Stmt::ImplicitCastExprClass: 7074 // If the result of an implicit cast is an l-value, we care about 7075 // the sub-expression; otherwise, the result here doesn't matter. 7076 return getPrimaryDecl(cast<ImplicitCastExpr>(E)->getSubExpr()); 7077 default: 7078 return 0; 7079 } 7080} 7081 7082/// CheckAddressOfOperand - The operand of & must be either a function 7083/// designator or an lvalue designating an object. If it is an lvalue, the 7084/// object cannot be declared with storage class register or be a bit field. 7085/// Note: The usual conversions are *not* applied to the operand of the & 7086/// operator (C99 6.3.2.1p[2-4]), and its result is never an lvalue. 7087/// In C++, the operand might be an overloaded function name, in which case 7088/// we allow the '&' but retain the overloaded-function type. 7089static QualType CheckAddressOfOperand(Sema &S, Expr *OrigOp, 7090 SourceLocation OpLoc) { 7091 if (OrigOp->isTypeDependent()) 7092 return S.Context.DependentTy; 7093 if (OrigOp->getType() == S.Context.OverloadTy) 7094 return S.Context.OverloadTy; 7095 if (OrigOp->getType() == S.Context.UnknownAnyTy) 7096 return S.Context.UnknownAnyTy; 7097 if (OrigOp->getType() == S.Context.BoundMemberTy) { 7098 S.Diag(OpLoc, diag::err_invalid_form_pointer_member_function) 7099 << OrigOp->getSourceRange(); 7100 return QualType(); 7101 } 7102 7103 assert(!OrigOp->getType()->isPlaceholderType()); 7104 7105 // Make sure to ignore parentheses in subsequent checks 7106 Expr *op = OrigOp->IgnoreParens(); 7107 7108 if (S.getLangOptions().C99) { 7109 // Implement C99-only parts of addressof rules. 7110 if (UnaryOperator* uOp = dyn_cast<UnaryOperator>(op)) { 7111 if (uOp->getOpcode() == UO_Deref) 7112 // Per C99 6.5.3.2, the address of a deref always returns a valid result 7113 // (assuming the deref expression is valid). 7114 return uOp->getSubExpr()->getType(); 7115 } 7116 // Technically, there should be a check for array subscript 7117 // expressions here, but the result of one is always an lvalue anyway. 7118 } 7119 ValueDecl *dcl = getPrimaryDecl(op); 7120 Expr::LValueClassification lval = op->ClassifyLValue(S.Context); 7121 7122 if (lval == Expr::LV_ClassTemporary) { 7123 bool sfinae = S.isSFINAEContext(); 7124 S.Diag(OpLoc, sfinae ? diag::err_typecheck_addrof_class_temporary 7125 : diag::ext_typecheck_addrof_class_temporary) 7126 << op->getType() << op->getSourceRange(); 7127 if (sfinae) 7128 return QualType(); 7129 } else if (isa<ObjCSelectorExpr>(op)) { 7130 return S.Context.getPointerType(op->getType()); 7131 } else if (lval == Expr::LV_MemberFunction) { 7132 // If it's an instance method, make a member pointer. 7133 // The expression must have exactly the form &A::foo. 7134 7135 // If the underlying expression isn't a decl ref, give up. 7136 if (!isa<DeclRefExpr>(op)) { 7137 S.Diag(OpLoc, diag::err_invalid_form_pointer_member_function) 7138 << OrigOp->getSourceRange(); 7139 return QualType(); 7140 } 7141 DeclRefExpr *DRE = cast<DeclRefExpr>(op); 7142 CXXMethodDecl *MD = cast<CXXMethodDecl>(DRE->getDecl()); 7143 7144 // The id-expression was parenthesized. 7145 if (OrigOp != DRE) { 7146 S.Diag(OpLoc, diag::err_parens_pointer_member_function) 7147 << OrigOp->getSourceRange(); 7148 7149 // The method was named without a qualifier. 7150 } else if (!DRE->getQualifier()) { 7151 S.Diag(OpLoc, diag::err_unqualified_pointer_member_function) 7152 << op->getSourceRange(); 7153 } 7154 7155 return S.Context.getMemberPointerType(op->getType(), 7156 S.Context.getTypeDeclType(MD->getParent()).getTypePtr()); 7157 } else if (lval != Expr::LV_Valid && lval != Expr::LV_IncompleteVoidType) { 7158 // C99 6.5.3.2p1 7159 // The operand must be either an l-value or a function designator 7160 if (!op->getType()->isFunctionType()) { 7161 // FIXME: emit more specific diag... 7162 S.Diag(OpLoc, diag::err_typecheck_invalid_lvalue_addrof) 7163 << op->getSourceRange(); 7164 return QualType(); 7165 } 7166 } else if (op->getObjectKind() == OK_BitField) { // C99 6.5.3.2p1 7167 // The operand cannot be a bit-field 7168 S.Diag(OpLoc, diag::err_typecheck_address_of) 7169 << "bit-field" << op->getSourceRange(); 7170 return QualType(); 7171 } else if (op->getObjectKind() == OK_VectorComponent) { 7172 // The operand cannot be an element of a vector 7173 S.Diag(OpLoc, diag::err_typecheck_address_of) 7174 << "vector element" << op->getSourceRange(); 7175 return QualType(); 7176 } else if (op->getObjectKind() == OK_ObjCProperty) { 7177 // cannot take address of a property expression. 7178 S.Diag(OpLoc, diag::err_typecheck_address_of) 7179 << "property expression" << op->getSourceRange(); 7180 return QualType(); 7181 } else if (dcl) { // C99 6.5.3.2p1 7182 // We have an lvalue with a decl. Make sure the decl is not declared 7183 // with the register storage-class specifier. 7184 if (const VarDecl *vd = dyn_cast<VarDecl>(dcl)) { 7185 // in C++ it is not error to take address of a register 7186 // variable (c++03 7.1.1P3) 7187 if (vd->getStorageClass() == SC_Register && 7188 !S.getLangOptions().CPlusPlus) { 7189 S.Diag(OpLoc, diag::err_typecheck_address_of) 7190 << "register variable" << op->getSourceRange(); 7191 return QualType(); 7192 } 7193 } else if (isa<FunctionTemplateDecl>(dcl)) { 7194 return S.Context.OverloadTy; 7195 } else if (isa<FieldDecl>(dcl) || isa<IndirectFieldDecl>(dcl)) { 7196 // Okay: we can take the address of a field. 7197 // Could be a pointer to member, though, if there is an explicit 7198 // scope qualifier for the class. 7199 if (isa<DeclRefExpr>(op) && cast<DeclRefExpr>(op)->getQualifier()) { 7200 DeclContext *Ctx = dcl->getDeclContext(); 7201 if (Ctx && Ctx->isRecord()) { 7202 if (dcl->getType()->isReferenceType()) { 7203 S.Diag(OpLoc, 7204 diag::err_cannot_form_pointer_to_member_of_reference_type) 7205 << dcl->getDeclName() << dcl->getType(); 7206 return QualType(); 7207 } 7208 7209 while (cast<RecordDecl>(Ctx)->isAnonymousStructOrUnion()) 7210 Ctx = Ctx->getParent(); 7211 return S.Context.getMemberPointerType(op->getType(), 7212 S.Context.getTypeDeclType(cast<RecordDecl>(Ctx)).getTypePtr()); 7213 } 7214 } 7215 } else if (!isa<FunctionDecl>(dcl)) 7216 assert(0 && "Unknown/unexpected decl type"); 7217 } 7218 7219 if (lval == Expr::LV_IncompleteVoidType) { 7220 // Taking the address of a void variable is technically illegal, but we 7221 // allow it in cases which are otherwise valid. 7222 // Example: "extern void x; void* y = &x;". 7223 S.Diag(OpLoc, diag::ext_typecheck_addrof_void) << op->getSourceRange(); 7224 } 7225 7226 // If the operand has type "type", the result has type "pointer to type". 7227 if (op->getType()->isObjCObjectType()) 7228 return S.Context.getObjCObjectPointerType(op->getType()); 7229 return S.Context.getPointerType(op->getType()); 7230} 7231 7232/// CheckIndirectionOperand - Type check unary indirection (prefix '*'). 7233static QualType CheckIndirectionOperand(Sema &S, Expr *Op, ExprValueKind &VK, 7234 SourceLocation OpLoc) { 7235 if (Op->isTypeDependent()) 7236 return S.Context.DependentTy; 7237 7238 ExprResult ConvResult = S.UsualUnaryConversions(Op); 7239 if (ConvResult.isInvalid()) 7240 return QualType(); 7241 Op = ConvResult.take(); 7242 QualType OpTy = Op->getType(); 7243 QualType Result; 7244 7245 if (isa<CXXReinterpretCastExpr>(Op)) { 7246 QualType OpOrigType = Op->IgnoreParenCasts()->getType(); 7247 S.CheckCompatibleReinterpretCast(OpOrigType, OpTy, /*IsDereference*/true, 7248 Op->getSourceRange()); 7249 } 7250 7251 // Note that per both C89 and C99, indirection is always legal, even if OpTy 7252 // is an incomplete type or void. It would be possible to warn about 7253 // dereferencing a void pointer, but it's completely well-defined, and such a 7254 // warning is unlikely to catch any mistakes. 7255 if (const PointerType *PT = OpTy->getAs<PointerType>()) 7256 Result = PT->getPointeeType(); 7257 else if (const ObjCObjectPointerType *OPT = 7258 OpTy->getAs<ObjCObjectPointerType>()) 7259 Result = OPT->getPointeeType(); 7260 else { 7261 ExprResult PR = S.CheckPlaceholderExpr(Op); 7262 if (PR.isInvalid()) return QualType(); 7263 if (PR.take() != Op) 7264 return CheckIndirectionOperand(S, PR.take(), VK, OpLoc); 7265 } 7266 7267 if (Result.isNull()) { 7268 S.Diag(OpLoc, diag::err_typecheck_indirection_requires_pointer) 7269 << OpTy << Op->getSourceRange(); 7270 return QualType(); 7271 } 7272 7273 // Dereferences are usually l-values... 7274 VK = VK_LValue; 7275 7276 // ...except that certain expressions are never l-values in C. 7277 if (!S.getLangOptions().CPlusPlus && Result.isCForbiddenLValueType()) 7278 VK = VK_RValue; 7279 7280 return Result; 7281} 7282 7283static inline BinaryOperatorKind ConvertTokenKindToBinaryOpcode( 7284 tok::TokenKind Kind) { 7285 BinaryOperatorKind Opc; 7286 switch (Kind) { 7287 default: assert(0 && "Unknown binop!"); 7288 case tok::periodstar: Opc = BO_PtrMemD; break; 7289 case tok::arrowstar: Opc = BO_PtrMemI; break; 7290 case tok::star: Opc = BO_Mul; break; 7291 case tok::slash: Opc = BO_Div; break; 7292 case tok::percent: Opc = BO_Rem; break; 7293 case tok::plus: Opc = BO_Add; break; 7294 case tok::minus: Opc = BO_Sub; break; 7295 case tok::lessless: Opc = BO_Shl; break; 7296 case tok::greatergreater: Opc = BO_Shr; break; 7297 case tok::lessequal: Opc = BO_LE; break; 7298 case tok::less: Opc = BO_LT; break; 7299 case tok::greaterequal: Opc = BO_GE; break; 7300 case tok::greater: Opc = BO_GT; break; 7301 case tok::exclaimequal: Opc = BO_NE; break; 7302 case tok::equalequal: Opc = BO_EQ; break; 7303 case tok::amp: Opc = BO_And; break; 7304 case tok::caret: Opc = BO_Xor; break; 7305 case tok::pipe: Opc = BO_Or; break; 7306 case tok::ampamp: Opc = BO_LAnd; break; 7307 case tok::pipepipe: Opc = BO_LOr; break; 7308 case tok::equal: Opc = BO_Assign; break; 7309 case tok::starequal: Opc = BO_MulAssign; break; 7310 case tok::slashequal: Opc = BO_DivAssign; break; 7311 case tok::percentequal: Opc = BO_RemAssign; break; 7312 case tok::plusequal: Opc = BO_AddAssign; break; 7313 case tok::minusequal: Opc = BO_SubAssign; break; 7314 case tok::lesslessequal: Opc = BO_ShlAssign; break; 7315 case tok::greatergreaterequal: Opc = BO_ShrAssign; break; 7316 case tok::ampequal: Opc = BO_AndAssign; break; 7317 case tok::caretequal: Opc = BO_XorAssign; break; 7318 case tok::pipeequal: Opc = BO_OrAssign; break; 7319 case tok::comma: Opc = BO_Comma; break; 7320 } 7321 return Opc; 7322} 7323 7324static inline UnaryOperatorKind ConvertTokenKindToUnaryOpcode( 7325 tok::TokenKind Kind) { 7326 UnaryOperatorKind Opc; 7327 switch (Kind) { 7328 default: assert(0 && "Unknown unary op!"); 7329 case tok::plusplus: Opc = UO_PreInc; break; 7330 case tok::minusminus: Opc = UO_PreDec; break; 7331 case tok::amp: Opc = UO_AddrOf; break; 7332 case tok::star: Opc = UO_Deref; break; 7333 case tok::plus: Opc = UO_Plus; break; 7334 case tok::minus: Opc = UO_Minus; break; 7335 case tok::tilde: Opc = UO_Not; break; 7336 case tok::exclaim: Opc = UO_LNot; break; 7337 case tok::kw___real: Opc = UO_Real; break; 7338 case tok::kw___imag: Opc = UO_Imag; break; 7339 case tok::kw___extension__: Opc = UO_Extension; break; 7340 } 7341 return Opc; 7342} 7343 7344/// DiagnoseSelfAssignment - Emits a warning if a value is assigned to itself. 7345/// This warning is only emitted for builtin assignment operations. It is also 7346/// suppressed in the event of macro expansions. 7347static void DiagnoseSelfAssignment(Sema &S, Expr *lhs, Expr *rhs, 7348 SourceLocation OpLoc) { 7349 if (!S.ActiveTemplateInstantiations.empty()) 7350 return; 7351 if (OpLoc.isInvalid() || OpLoc.isMacroID()) 7352 return; 7353 lhs = lhs->IgnoreParenImpCasts(); 7354 rhs = rhs->IgnoreParenImpCasts(); 7355 const DeclRefExpr *LeftDeclRef = dyn_cast<DeclRefExpr>(lhs); 7356 const DeclRefExpr *RightDeclRef = dyn_cast<DeclRefExpr>(rhs); 7357 if (!LeftDeclRef || !RightDeclRef || 7358 LeftDeclRef->getLocation().isMacroID() || 7359 RightDeclRef->getLocation().isMacroID()) 7360 return; 7361 const ValueDecl *LeftDecl = 7362 cast<ValueDecl>(LeftDeclRef->getDecl()->getCanonicalDecl()); 7363 const ValueDecl *RightDecl = 7364 cast<ValueDecl>(RightDeclRef->getDecl()->getCanonicalDecl()); 7365 if (LeftDecl != RightDecl) 7366 return; 7367 if (LeftDecl->getType().isVolatileQualified()) 7368 return; 7369 if (const ReferenceType *RefTy = LeftDecl->getType()->getAs<ReferenceType>()) 7370 if (RefTy->getPointeeType().isVolatileQualified()) 7371 return; 7372 7373 S.Diag(OpLoc, diag::warn_self_assignment) 7374 << LeftDeclRef->getType() 7375 << lhs->getSourceRange() << rhs->getSourceRange(); 7376} 7377 7378/// CreateBuiltinBinOp - Creates a new built-in binary operation with 7379/// operator @p Opc at location @c TokLoc. This routine only supports 7380/// built-in operations; ActOnBinOp handles overloaded operators. 7381ExprResult Sema::CreateBuiltinBinOp(SourceLocation OpLoc, 7382 BinaryOperatorKind Opc, 7383 Expr *lhsExpr, Expr *rhsExpr) { 7384 ExprResult lhs = Owned(lhsExpr), rhs = Owned(rhsExpr); 7385 QualType ResultTy; // Result type of the binary operator. 7386 // The following two variables are used for compound assignment operators 7387 QualType CompLHSTy; // Type of LHS after promotions for computation 7388 QualType CompResultTy; // Type of computation result 7389 ExprValueKind VK = VK_RValue; 7390 ExprObjectKind OK = OK_Ordinary; 7391 7392 // Check if a 'foo<int>' involved in a binary op, identifies a single 7393 // function unambiguously (i.e. an lvalue ala 13.4) 7394 // But since an assignment can trigger target based overload, exclude it in 7395 // our blind search. i.e: 7396 // template<class T> void f(); template<class T, class U> void f(U); 7397 // f<int> == 0; // resolve f<int> blindly 7398 // void (*p)(int); p = f<int>; // resolve f<int> using target 7399 if (Opc != BO_Assign) { 7400 ExprResult resolvedLHS = CheckPlaceholderExpr(lhs.get()); 7401 if (!resolvedLHS.isUsable()) return ExprError(); 7402 lhs = move(resolvedLHS); 7403 7404 ExprResult resolvedRHS = CheckPlaceholderExpr(rhs.get()); 7405 if (!resolvedRHS.isUsable()) return ExprError(); 7406 rhs = move(resolvedRHS); 7407 } 7408 7409 // The canonical way to check for a GNU null is with isNullPointerConstant, 7410 // but we use a bit of a hack here for speed; this is a relatively 7411 // hot path, and isNullPointerConstant is slow. 7412 bool LeftNull = isa<GNUNullExpr>(lhs.get()->IgnoreParenImpCasts()); 7413 bool RightNull = isa<GNUNullExpr>(rhs.get()->IgnoreParenImpCasts()); 7414 7415 // Detect when a NULL constant is used improperly in an expression. These 7416 // are mainly cases where the null pointer is used as an integer instead 7417 // of a pointer. 7418 if (LeftNull || RightNull) { 7419 // Avoid analyzing cases where the result will either be invalid (and 7420 // diagnosed as such) or entirely valid and not something to warn about. 7421 QualType LeftType = lhs.get()->getType(); 7422 QualType RightType = rhs.get()->getType(); 7423 if (!LeftType->isBlockPointerType() && !LeftType->isMemberPointerType() && 7424 !LeftType->isFunctionType() && 7425 !RightType->isBlockPointerType() && 7426 !RightType->isMemberPointerType() && 7427 !RightType->isFunctionType()) { 7428 if (Opc == BO_Mul || Opc == BO_Div || Opc == BO_Rem || Opc == BO_Add || 7429 Opc == BO_Sub || Opc == BO_Shl || Opc == BO_Shr || Opc == BO_And || 7430 Opc == BO_Xor || Opc == BO_Or || Opc == BO_MulAssign || 7431 Opc == BO_DivAssign || Opc == BO_AddAssign || Opc == BO_SubAssign || 7432 Opc == BO_RemAssign || Opc == BO_ShlAssign || Opc == BO_ShrAssign || 7433 Opc == BO_AndAssign || Opc == BO_OrAssign || Opc == BO_XorAssign) { 7434 // These are the operations that would not make sense with a null pointer 7435 // no matter what the other expression is. 7436 Diag(OpLoc, diag::warn_null_in_arithmetic_operation) 7437 << (LeftNull ? lhs.get()->getSourceRange() : SourceRange()) 7438 << (RightNull ? rhs.get()->getSourceRange() : SourceRange()); 7439 } else if (Opc == BO_LE || Opc == BO_LT || Opc == BO_GE || Opc == BO_GT || 7440 Opc == BO_EQ || Opc == BO_NE) { 7441 // These are the operations that would not make sense with a null pointer 7442 // if the other expression the other expression is not a pointer. 7443 if (LeftNull != RightNull && 7444 !LeftType->isAnyPointerType() && 7445 !LeftType->canDecayToPointerType() && 7446 !RightType->isAnyPointerType() && 7447 !RightType->canDecayToPointerType()) { 7448 Diag(OpLoc, diag::warn_null_in_arithmetic_operation) 7449 << (LeftNull ? lhs.get()->getSourceRange() 7450 : rhs.get()->getSourceRange()); 7451 } 7452 } 7453 } 7454 } 7455 7456 switch (Opc) { 7457 case BO_Assign: 7458 ResultTy = CheckAssignmentOperands(lhs.get(), rhs, OpLoc, QualType()); 7459 if (getLangOptions().CPlusPlus && 7460 lhs.get()->getObjectKind() != OK_ObjCProperty) { 7461 VK = lhs.get()->getValueKind(); 7462 OK = lhs.get()->getObjectKind(); 7463 } 7464 if (!ResultTy.isNull()) 7465 DiagnoseSelfAssignment(*this, lhs.get(), rhs.get(), OpLoc); 7466 break; 7467 case BO_PtrMemD: 7468 case BO_PtrMemI: 7469 ResultTy = CheckPointerToMemberOperands(lhs, rhs, VK, OpLoc, 7470 Opc == BO_PtrMemI); 7471 break; 7472 case BO_Mul: 7473 case BO_Div: 7474 ResultTy = CheckMultiplyDivideOperands(lhs, rhs, OpLoc, false, 7475 Opc == BO_Div); 7476 break; 7477 case BO_Rem: 7478 ResultTy = CheckRemainderOperands(lhs, rhs, OpLoc); 7479 break; 7480 case BO_Add: 7481 ResultTy = CheckAdditionOperands(lhs, rhs, OpLoc); 7482 break; 7483 case BO_Sub: 7484 ResultTy = CheckSubtractionOperands(lhs, rhs, OpLoc); 7485 break; 7486 case BO_Shl: 7487 case BO_Shr: 7488 ResultTy = CheckShiftOperands(lhs, rhs, OpLoc, Opc); 7489 break; 7490 case BO_LE: 7491 case BO_LT: 7492 case BO_GE: 7493 case BO_GT: 7494 ResultTy = CheckCompareOperands(lhs, rhs, OpLoc, Opc, true); 7495 break; 7496 case BO_EQ: 7497 case BO_NE: 7498 ResultTy = CheckCompareOperands(lhs, rhs, OpLoc, Opc, false); 7499 break; 7500 case BO_And: 7501 case BO_Xor: 7502 case BO_Or: 7503 ResultTy = CheckBitwiseOperands(lhs, rhs, OpLoc); 7504 break; 7505 case BO_LAnd: 7506 case BO_LOr: 7507 ResultTy = CheckLogicalOperands(lhs, rhs, OpLoc, Opc); 7508 break; 7509 case BO_MulAssign: 7510 case BO_DivAssign: 7511 CompResultTy = CheckMultiplyDivideOperands(lhs, rhs, OpLoc, true, 7512 Opc == BO_DivAssign); 7513 CompLHSTy = CompResultTy; 7514 if (!CompResultTy.isNull() && !lhs.isInvalid() && !rhs.isInvalid()) 7515 ResultTy = CheckAssignmentOperands(lhs.get(), rhs, OpLoc, CompResultTy); 7516 break; 7517 case BO_RemAssign: 7518 CompResultTy = CheckRemainderOperands(lhs, rhs, OpLoc, true); 7519 CompLHSTy = CompResultTy; 7520 if (!CompResultTy.isNull() && !lhs.isInvalid() && !rhs.isInvalid()) 7521 ResultTy = CheckAssignmentOperands(lhs.get(), rhs, OpLoc, CompResultTy); 7522 break; 7523 case BO_AddAssign: 7524 CompResultTy = CheckAdditionOperands(lhs, rhs, OpLoc, &CompLHSTy); 7525 if (!CompResultTy.isNull() && !lhs.isInvalid() && !rhs.isInvalid()) 7526 ResultTy = CheckAssignmentOperands(lhs.get(), rhs, OpLoc, CompResultTy); 7527 break; 7528 case BO_SubAssign: 7529 CompResultTy = CheckSubtractionOperands(lhs, rhs, OpLoc, &CompLHSTy); 7530 if (!CompResultTy.isNull() && !lhs.isInvalid() && !rhs.isInvalid()) 7531 ResultTy = CheckAssignmentOperands(lhs.get(), rhs, OpLoc, CompResultTy); 7532 break; 7533 case BO_ShlAssign: 7534 case BO_ShrAssign: 7535 CompResultTy = CheckShiftOperands(lhs, rhs, OpLoc, Opc, true); 7536 CompLHSTy = CompResultTy; 7537 if (!CompResultTy.isNull() && !lhs.isInvalid() && !rhs.isInvalid()) 7538 ResultTy = CheckAssignmentOperands(lhs.get(), rhs, OpLoc, CompResultTy); 7539 break; 7540 case BO_AndAssign: 7541 case BO_XorAssign: 7542 case BO_OrAssign: 7543 CompResultTy = CheckBitwiseOperands(lhs, rhs, OpLoc, true); 7544 CompLHSTy = CompResultTy; 7545 if (!CompResultTy.isNull() && !lhs.isInvalid() && !rhs.isInvalid()) 7546 ResultTy = CheckAssignmentOperands(lhs.get(), rhs, OpLoc, CompResultTy); 7547 break; 7548 case BO_Comma: 7549 ResultTy = CheckCommaOperands(*this, lhs, rhs, OpLoc); 7550 if (getLangOptions().CPlusPlus && !rhs.isInvalid()) { 7551 VK = rhs.get()->getValueKind(); 7552 OK = rhs.get()->getObjectKind(); 7553 } 7554 break; 7555 } 7556 if (ResultTy.isNull() || lhs.isInvalid() || rhs.isInvalid()) 7557 return ExprError(); 7558 if (CompResultTy.isNull()) 7559 return Owned(new (Context) BinaryOperator(lhs.take(), rhs.take(), Opc, 7560 ResultTy, VK, OK, OpLoc)); 7561 if (getLangOptions().CPlusPlus && lhs.get()->getObjectKind() != OK_ObjCProperty) { 7562 VK = VK_LValue; 7563 OK = lhs.get()->getObjectKind(); 7564 } 7565 return Owned(new (Context) CompoundAssignOperator(lhs.take(), rhs.take(), Opc, 7566 ResultTy, VK, OK, CompLHSTy, 7567 CompResultTy, OpLoc)); 7568} 7569 7570/// DiagnoseBitwisePrecedence - Emit a warning when bitwise and comparison 7571/// operators are mixed in a way that suggests that the programmer forgot that 7572/// comparison operators have higher precedence. The most typical example of 7573/// such code is "flags & 0x0020 != 0", which is equivalent to "flags & 1". 7574static void DiagnoseBitwisePrecedence(Sema &Self, BinaryOperatorKind Opc, 7575 SourceLocation OpLoc,Expr *lhs,Expr *rhs){ 7576 typedef BinaryOperator BinOp; 7577 BinOp::Opcode lhsopc = static_cast<BinOp::Opcode>(-1), 7578 rhsopc = static_cast<BinOp::Opcode>(-1); 7579 if (BinOp *BO = dyn_cast<BinOp>(lhs)) 7580 lhsopc = BO->getOpcode(); 7581 if (BinOp *BO = dyn_cast<BinOp>(rhs)) 7582 rhsopc = BO->getOpcode(); 7583 7584 // Subs are not binary operators. 7585 if (lhsopc == -1 && rhsopc == -1) 7586 return; 7587 7588 // Bitwise operations are sometimes used as eager logical ops. 7589 // Don't diagnose this. 7590 if ((BinOp::isComparisonOp(lhsopc) || BinOp::isBitwiseOp(lhsopc)) && 7591 (BinOp::isComparisonOp(rhsopc) || BinOp::isBitwiseOp(rhsopc))) 7592 return; 7593 7594 if (BinOp::isComparisonOp(lhsopc)) { 7595 Self.Diag(OpLoc, diag::warn_precedence_bitwise_rel) 7596 << SourceRange(lhs->getLocStart(), OpLoc) 7597 << BinOp::getOpcodeStr(Opc) << BinOp::getOpcodeStr(lhsopc); 7598 SuggestParentheses(Self, OpLoc, 7599 Self.PDiag(diag::note_precedence_bitwise_silence) 7600 << BinOp::getOpcodeStr(lhsopc), 7601 lhs->getSourceRange()); 7602 SuggestParentheses(Self, OpLoc, 7603 Self.PDiag(diag::note_precedence_bitwise_first) 7604 << BinOp::getOpcodeStr(Opc), 7605 SourceRange(cast<BinOp>(lhs)->getRHS()->getLocStart(), rhs->getLocEnd())); 7606 } else if (BinOp::isComparisonOp(rhsopc)) { 7607 Self.Diag(OpLoc, diag::warn_precedence_bitwise_rel) 7608 << SourceRange(OpLoc, rhs->getLocEnd()) 7609 << BinOp::getOpcodeStr(Opc) << BinOp::getOpcodeStr(rhsopc); 7610 SuggestParentheses(Self, OpLoc, 7611 Self.PDiag(diag::note_precedence_bitwise_silence) 7612 << BinOp::getOpcodeStr(rhsopc), 7613 rhs->getSourceRange()); 7614 SuggestParentheses(Self, OpLoc, 7615 Self.PDiag(diag::note_precedence_bitwise_first) 7616 << BinOp::getOpcodeStr(Opc), 7617 SourceRange(lhs->getLocStart(), 7618 cast<BinOp>(rhs)->getLHS()->getLocStart())); 7619 } 7620} 7621 7622/// \brief It accepts a '&' expr that is inside a '|' one. 7623/// Emit a diagnostic together with a fixit hint that wraps the '&' expression 7624/// in parentheses. 7625static void 7626EmitDiagnosticForBitwiseAndInBitwiseOr(Sema &Self, SourceLocation OpLoc, 7627 BinaryOperator *Bop) { 7628 assert(Bop->getOpcode() == BO_And); 7629 Self.Diag(Bop->getOperatorLoc(), diag::warn_bitwise_and_in_bitwise_or) 7630 << Bop->getSourceRange() << OpLoc; 7631 SuggestParentheses(Self, Bop->getOperatorLoc(), 7632 Self.PDiag(diag::note_bitwise_and_in_bitwise_or_silence), 7633 Bop->getSourceRange()); 7634} 7635 7636/// \brief It accepts a '&&' expr that is inside a '||' one. 7637/// Emit a diagnostic together with a fixit hint that wraps the '&&' expression 7638/// in parentheses. 7639static void 7640EmitDiagnosticForLogicalAndInLogicalOr(Sema &Self, SourceLocation OpLoc, 7641 BinaryOperator *Bop) { 7642 assert(Bop->getOpcode() == BO_LAnd); 7643 Self.Diag(Bop->getOperatorLoc(), diag::warn_logical_and_in_logical_or) 7644 << Bop->getSourceRange() << OpLoc; 7645 SuggestParentheses(Self, Bop->getOperatorLoc(), 7646 Self.PDiag(diag::note_logical_and_in_logical_or_silence), 7647 Bop->getSourceRange()); 7648} 7649 7650/// \brief Returns true if the given expression can be evaluated as a constant 7651/// 'true'. 7652static bool EvaluatesAsTrue(Sema &S, Expr *E) { 7653 bool Res; 7654 return E->EvaluateAsBooleanCondition(Res, S.getASTContext()) && Res; 7655} 7656 7657/// \brief Returns true if the given expression can be evaluated as a constant 7658/// 'false'. 7659static bool EvaluatesAsFalse(Sema &S, Expr *E) { 7660 bool Res; 7661 return E->EvaluateAsBooleanCondition(Res, S.getASTContext()) && !Res; 7662} 7663 7664/// \brief Look for '&&' in the left hand of a '||' expr. 7665static void DiagnoseLogicalAndInLogicalOrLHS(Sema &S, SourceLocation OpLoc, 7666 Expr *OrLHS, Expr *OrRHS) { 7667 if (BinaryOperator *Bop = dyn_cast<BinaryOperator>(OrLHS)) { 7668 if (Bop->getOpcode() == BO_LAnd) { 7669 // If it's "a && b || 0" don't warn since the precedence doesn't matter. 7670 if (EvaluatesAsFalse(S, OrRHS)) 7671 return; 7672 // If it's "1 && a || b" don't warn since the precedence doesn't matter. 7673 if (!EvaluatesAsTrue(S, Bop->getLHS())) 7674 return EmitDiagnosticForLogicalAndInLogicalOr(S, OpLoc, Bop); 7675 } else if (Bop->getOpcode() == BO_LOr) { 7676 if (BinaryOperator *RBop = dyn_cast<BinaryOperator>(Bop->getRHS())) { 7677 // If it's "a || b && 1 || c" we didn't warn earlier for 7678 // "a || b && 1", but warn now. 7679 if (RBop->getOpcode() == BO_LAnd && EvaluatesAsTrue(S, RBop->getRHS())) 7680 return EmitDiagnosticForLogicalAndInLogicalOr(S, OpLoc, RBop); 7681 } 7682 } 7683 } 7684} 7685 7686/// \brief Look for '&&' in the right hand of a '||' expr. 7687static void DiagnoseLogicalAndInLogicalOrRHS(Sema &S, SourceLocation OpLoc, 7688 Expr *OrLHS, Expr *OrRHS) { 7689 if (BinaryOperator *Bop = dyn_cast<BinaryOperator>(OrRHS)) { 7690 if (Bop->getOpcode() == BO_LAnd) { 7691 // If it's "0 || a && b" don't warn since the precedence doesn't matter. 7692 if (EvaluatesAsFalse(S, OrLHS)) 7693 return; 7694 // If it's "a || b && 1" don't warn since the precedence doesn't matter. 7695 if (!EvaluatesAsTrue(S, Bop->getRHS())) 7696 return EmitDiagnosticForLogicalAndInLogicalOr(S, OpLoc, Bop); 7697 } 7698 } 7699} 7700 7701/// \brief Look for '&' in the left or right hand of a '|' expr. 7702static void DiagnoseBitwiseAndInBitwiseOr(Sema &S, SourceLocation OpLoc, 7703 Expr *OrArg) { 7704 if (BinaryOperator *Bop = dyn_cast<BinaryOperator>(OrArg)) { 7705 if (Bop->getOpcode() == BO_And) 7706 return EmitDiagnosticForBitwiseAndInBitwiseOr(S, OpLoc, Bop); 7707 } 7708} 7709 7710/// DiagnoseBinOpPrecedence - Emit warnings for expressions with tricky 7711/// precedence. 7712static void DiagnoseBinOpPrecedence(Sema &Self, BinaryOperatorKind Opc, 7713 SourceLocation OpLoc, Expr *lhs, Expr *rhs){ 7714 // Diagnose "arg1 'bitwise' arg2 'eq' arg3". 7715 if (BinaryOperator::isBitwiseOp(Opc)) 7716 DiagnoseBitwisePrecedence(Self, Opc, OpLoc, lhs, rhs); 7717 7718 // Diagnose "arg1 & arg2 | arg3" 7719 if (Opc == BO_Or && !OpLoc.isMacroID()/* Don't warn in macros. */) { 7720 DiagnoseBitwiseAndInBitwiseOr(Self, OpLoc, lhs); 7721 DiagnoseBitwiseAndInBitwiseOr(Self, OpLoc, rhs); 7722 } 7723 7724 // Warn about arg1 || arg2 && arg3, as GCC 4.3+ does. 7725 // We don't warn for 'assert(a || b && "bad")' since this is safe. 7726 if (Opc == BO_LOr && !OpLoc.isMacroID()/* Don't warn in macros. */) { 7727 DiagnoseLogicalAndInLogicalOrLHS(Self, OpLoc, lhs, rhs); 7728 DiagnoseLogicalAndInLogicalOrRHS(Self, OpLoc, lhs, rhs); 7729 } 7730} 7731 7732// Binary Operators. 'Tok' is the token for the operator. 7733ExprResult Sema::ActOnBinOp(Scope *S, SourceLocation TokLoc, 7734 tok::TokenKind Kind, 7735 Expr *lhs, Expr *rhs) { 7736 BinaryOperatorKind Opc = ConvertTokenKindToBinaryOpcode(Kind); 7737 assert((lhs != 0) && "ActOnBinOp(): missing left expression"); 7738 assert((rhs != 0) && "ActOnBinOp(): missing right expression"); 7739 7740 // Emit warnings for tricky precedence issues, e.g. "bitfield & 0x4 == 0" 7741 DiagnoseBinOpPrecedence(*this, Opc, TokLoc, lhs, rhs); 7742 7743 return BuildBinOp(S, TokLoc, Opc, lhs, rhs); 7744} 7745 7746ExprResult Sema::BuildBinOp(Scope *S, SourceLocation OpLoc, 7747 BinaryOperatorKind Opc, 7748 Expr *lhs, Expr *rhs) { 7749 if (getLangOptions().CPlusPlus) { 7750 bool UseBuiltinOperator; 7751 7752 if (lhs->isTypeDependent() || rhs->isTypeDependent()) { 7753 UseBuiltinOperator = false; 7754 } else if (Opc == BO_Assign && lhs->getObjectKind() == OK_ObjCProperty) { 7755 UseBuiltinOperator = true; 7756 } else { 7757 UseBuiltinOperator = !lhs->getType()->isOverloadableType() && 7758 !rhs->getType()->isOverloadableType(); 7759 } 7760 7761 if (!UseBuiltinOperator) { 7762 // Find all of the overloaded operators visible from this 7763 // point. We perform both an operator-name lookup from the local 7764 // scope and an argument-dependent lookup based on the types of 7765 // the arguments. 7766 UnresolvedSet<16> Functions; 7767 OverloadedOperatorKind OverOp 7768 = BinaryOperator::getOverloadedOperator(Opc); 7769 if (S && OverOp != OO_None) 7770 LookupOverloadedOperatorName(OverOp, S, lhs->getType(), rhs->getType(), 7771 Functions); 7772 7773 // Build the (potentially-overloaded, potentially-dependent) 7774 // binary operation. 7775 return CreateOverloadedBinOp(OpLoc, Opc, Functions, lhs, rhs); 7776 } 7777 } 7778 7779 // Build a built-in binary operation. 7780 return CreateBuiltinBinOp(OpLoc, Opc, lhs, rhs); 7781} 7782 7783ExprResult Sema::CreateBuiltinUnaryOp(SourceLocation OpLoc, 7784 UnaryOperatorKind Opc, 7785 Expr *InputExpr) { 7786 ExprResult Input = Owned(InputExpr); 7787 ExprValueKind VK = VK_RValue; 7788 ExprObjectKind OK = OK_Ordinary; 7789 QualType resultType; 7790 switch (Opc) { 7791 case UO_PreInc: 7792 case UO_PreDec: 7793 case UO_PostInc: 7794 case UO_PostDec: 7795 resultType = CheckIncrementDecrementOperand(*this, Input.get(), VK, OpLoc, 7796 Opc == UO_PreInc || 7797 Opc == UO_PostInc, 7798 Opc == UO_PreInc || 7799 Opc == UO_PreDec); 7800 break; 7801 case UO_AddrOf: 7802 resultType = CheckAddressOfOperand(*this, Input.get(), OpLoc); 7803 break; 7804 case UO_Deref: { 7805 ExprResult resolved = CheckPlaceholderExpr(Input.get()); 7806 if (!resolved.isUsable()) return ExprError(); 7807 Input = move(resolved); 7808 Input = DefaultFunctionArrayLvalueConversion(Input.take()); 7809 resultType = CheckIndirectionOperand(*this, Input.get(), VK, OpLoc); 7810 break; 7811 } 7812 case UO_Plus: 7813 case UO_Minus: 7814 Input = UsualUnaryConversions(Input.take()); 7815 if (Input.isInvalid()) return ExprError(); 7816 resultType = Input.get()->getType(); 7817 if (resultType->isDependentType()) 7818 break; 7819 if (resultType->isArithmeticType() || // C99 6.5.3.3p1 7820 resultType->isVectorType()) 7821 break; 7822 else if (getLangOptions().CPlusPlus && // C++ [expr.unary.op]p6-7 7823 resultType->isEnumeralType()) 7824 break; 7825 else if (getLangOptions().CPlusPlus && // C++ [expr.unary.op]p6 7826 Opc == UO_Plus && 7827 resultType->isPointerType()) 7828 break; 7829 else if (resultType->isPlaceholderType()) { 7830 Input = CheckPlaceholderExpr(Input.take()); 7831 if (Input.isInvalid()) return ExprError(); 7832 return CreateBuiltinUnaryOp(OpLoc, Opc, Input.take()); 7833 } 7834 7835 return ExprError(Diag(OpLoc, diag::err_typecheck_unary_expr) 7836 << resultType << Input.get()->getSourceRange()); 7837 7838 case UO_Not: // bitwise complement 7839 Input = UsualUnaryConversions(Input.take()); 7840 if (Input.isInvalid()) return ExprError(); 7841 resultType = Input.get()->getType(); 7842 if (resultType->isDependentType()) 7843 break; 7844 // C99 6.5.3.3p1. We allow complex int and float as a GCC extension. 7845 if (resultType->isComplexType() || resultType->isComplexIntegerType()) 7846 // C99 does not support '~' for complex conjugation. 7847 Diag(OpLoc, diag::ext_integer_complement_complex) 7848 << resultType << Input.get()->getSourceRange(); 7849 else if (resultType->hasIntegerRepresentation()) 7850 break; 7851 else if (resultType->isPlaceholderType()) { 7852 Input = CheckPlaceholderExpr(Input.take()); 7853 if (Input.isInvalid()) return ExprError(); 7854 return CreateBuiltinUnaryOp(OpLoc, Opc, Input.take()); 7855 } else { 7856 return ExprError(Diag(OpLoc, diag::err_typecheck_unary_expr) 7857 << resultType << Input.get()->getSourceRange()); 7858 } 7859 break; 7860 7861 case UO_LNot: // logical negation 7862 // Unlike +/-/~, integer promotions aren't done here (C99 6.5.3.3p5). 7863 Input = DefaultFunctionArrayLvalueConversion(Input.take()); 7864 if (Input.isInvalid()) return ExprError(); 7865 resultType = Input.get()->getType(); 7866 if (resultType->isDependentType()) 7867 break; 7868 if (resultType->isScalarType()) { 7869 // C99 6.5.3.3p1: ok, fallthrough; 7870 if (Context.getLangOptions().CPlusPlus) { 7871 // C++03 [expr.unary.op]p8, C++0x [expr.unary.op]p9: 7872 // operand contextually converted to bool. 7873 Input = ImpCastExprToType(Input.take(), Context.BoolTy, 7874 ScalarTypeToBooleanCastKind(resultType)); 7875 } 7876 } else if (resultType->isPlaceholderType()) { 7877 Input = CheckPlaceholderExpr(Input.take()); 7878 if (Input.isInvalid()) return ExprError(); 7879 return CreateBuiltinUnaryOp(OpLoc, Opc, Input.take()); 7880 } else { 7881 return ExprError(Diag(OpLoc, diag::err_typecheck_unary_expr) 7882 << resultType << Input.get()->getSourceRange()); 7883 } 7884 7885 // LNot always has type int. C99 6.5.3.3p5. 7886 // In C++, it's bool. C++ 5.3.1p8 7887 resultType = Context.getLogicalOperationType(); 7888 break; 7889 case UO_Real: 7890 case UO_Imag: 7891 resultType = CheckRealImagOperand(*this, Input, OpLoc, Opc == UO_Real); 7892 // _Real and _Imag map ordinary l-values into ordinary l-values. 7893 if (Input.isInvalid()) return ExprError(); 7894 if (Input.get()->getValueKind() != VK_RValue && 7895 Input.get()->getObjectKind() == OK_Ordinary) 7896 VK = Input.get()->getValueKind(); 7897 break; 7898 case UO_Extension: 7899 resultType = Input.get()->getType(); 7900 VK = Input.get()->getValueKind(); 7901 OK = Input.get()->getObjectKind(); 7902 break; 7903 } 7904 if (resultType.isNull() || Input.isInvalid()) 7905 return ExprError(); 7906 7907 return Owned(new (Context) UnaryOperator(Input.take(), Opc, resultType, 7908 VK, OK, OpLoc)); 7909} 7910 7911ExprResult Sema::BuildUnaryOp(Scope *S, SourceLocation OpLoc, 7912 UnaryOperatorKind Opc, 7913 Expr *Input) { 7914 if (getLangOptions().CPlusPlus && Input->getType()->isOverloadableType() && 7915 UnaryOperator::getOverloadedOperator(Opc) != OO_None) { 7916 // Find all of the overloaded operators visible from this 7917 // point. We perform both an operator-name lookup from the local 7918 // scope and an argument-dependent lookup based on the types of 7919 // the arguments. 7920 UnresolvedSet<16> Functions; 7921 OverloadedOperatorKind OverOp = UnaryOperator::getOverloadedOperator(Opc); 7922 if (S && OverOp != OO_None) 7923 LookupOverloadedOperatorName(OverOp, S, Input->getType(), QualType(), 7924 Functions); 7925 7926 return CreateOverloadedUnaryOp(OpLoc, Opc, Functions, Input); 7927 } 7928 7929 return CreateBuiltinUnaryOp(OpLoc, Opc, Input); 7930} 7931 7932// Unary Operators. 'Tok' is the token for the operator. 7933ExprResult Sema::ActOnUnaryOp(Scope *S, SourceLocation OpLoc, 7934 tok::TokenKind Op, Expr *Input) { 7935 return BuildUnaryOp(S, OpLoc, ConvertTokenKindToUnaryOpcode(Op), Input); 7936} 7937 7938/// ActOnAddrLabel - Parse the GNU address of label extension: "&&foo". 7939ExprResult Sema::ActOnAddrLabel(SourceLocation OpLoc, SourceLocation LabLoc, 7940 LabelDecl *TheDecl) { 7941 TheDecl->setUsed(); 7942 // Create the AST node. The address of a label always has type 'void*'. 7943 return Owned(new (Context) AddrLabelExpr(OpLoc, LabLoc, TheDecl, 7944 Context.getPointerType(Context.VoidTy))); 7945} 7946 7947/// Given the last statement in a statement-expression, check whether 7948/// the result is a producing expression (like a call to an 7949/// ns_returns_retained function) and, if so, rebuild it to hoist the 7950/// release out of the full-expression. Otherwise, return null. 7951/// Cannot fail. 7952static Expr *maybeRebuildARCConsumingStmt(Stmt *s) { 7953 // Should always be wrapped with one of these. 7954 ExprWithCleanups *cleanups = dyn_cast<ExprWithCleanups>(s); 7955 if (!cleanups) return 0; 7956 7957 ImplicitCastExpr *cast = dyn_cast<ImplicitCastExpr>(cleanups->getSubExpr()); 7958 if (!cast || cast->getCastKind() != CK_ObjCConsumeObject) 7959 return 0; 7960 7961 // Splice out the cast. This shouldn't modify any interesting 7962 // features of the statement. 7963 Expr *producer = cast->getSubExpr(); 7964 assert(producer->getType() == cast->getType()); 7965 assert(producer->getValueKind() == cast->getValueKind()); 7966 cleanups->setSubExpr(producer); 7967 return cleanups; 7968} 7969 7970ExprResult 7971Sema::ActOnStmtExpr(SourceLocation LPLoc, Stmt *SubStmt, 7972 SourceLocation RPLoc) { // "({..})" 7973 assert(SubStmt && isa<CompoundStmt>(SubStmt) && "Invalid action invocation!"); 7974 CompoundStmt *Compound = cast<CompoundStmt>(SubStmt); 7975 7976 bool isFileScope 7977 = (getCurFunctionOrMethodDecl() == 0) && (getCurBlock() == 0); 7978 if (isFileScope) 7979 return ExprError(Diag(LPLoc, diag::err_stmtexpr_file_scope)); 7980 7981 // FIXME: there are a variety of strange constraints to enforce here, for 7982 // example, it is not possible to goto into a stmt expression apparently. 7983 // More semantic analysis is needed. 7984 7985 // If there are sub stmts in the compound stmt, take the type of the last one 7986 // as the type of the stmtexpr. 7987 QualType Ty = Context.VoidTy; 7988 bool StmtExprMayBindToTemp = false; 7989 if (!Compound->body_empty()) { 7990 Stmt *LastStmt = Compound->body_back(); 7991 LabelStmt *LastLabelStmt = 0; 7992 // If LastStmt is a label, skip down through into the body. 7993 while (LabelStmt *Label = dyn_cast<LabelStmt>(LastStmt)) { 7994 LastLabelStmt = Label; 7995 LastStmt = Label->getSubStmt(); 7996 } 7997 7998 if (Expr *LastE = dyn_cast<Expr>(LastStmt)) { 7999 // Do function/array conversion on the last expression, but not 8000 // lvalue-to-rvalue. However, initialize an unqualified type. 8001 ExprResult LastExpr = DefaultFunctionArrayConversion(LastE); 8002 if (LastExpr.isInvalid()) 8003 return ExprError(); 8004 Ty = LastExpr.get()->getType().getUnqualifiedType(); 8005 8006 if (!Ty->isDependentType() && !LastExpr.get()->isTypeDependent()) { 8007 // In ARC, if the final expression ends in a consume, splice 8008 // the consume out and bind it later. In the alternate case 8009 // (when dealing with a retainable type), the result 8010 // initialization will create a produce. In both cases the 8011 // result will be +1, and we'll need to balance that out with 8012 // a bind. 8013 if (Expr *rebuiltLastStmt 8014 = maybeRebuildARCConsumingStmt(LastExpr.get())) { 8015 LastExpr = rebuiltLastStmt; 8016 } else { 8017 LastExpr = PerformCopyInitialization( 8018 InitializedEntity::InitializeResult(LPLoc, 8019 Ty, 8020 false), 8021 SourceLocation(), 8022 LastExpr); 8023 } 8024 8025 if (LastExpr.isInvalid()) 8026 return ExprError(); 8027 if (LastExpr.get() != 0) { 8028 if (!LastLabelStmt) 8029 Compound->setLastStmt(LastExpr.take()); 8030 else 8031 LastLabelStmt->setSubStmt(LastExpr.take()); 8032 StmtExprMayBindToTemp = true; 8033 } 8034 } 8035 } 8036 } 8037 8038 // FIXME: Check that expression type is complete/non-abstract; statement 8039 // expressions are not lvalues. 8040 Expr *ResStmtExpr = new (Context) StmtExpr(Compound, Ty, LPLoc, RPLoc); 8041 if (StmtExprMayBindToTemp) 8042 return MaybeBindToTemporary(ResStmtExpr); 8043 return Owned(ResStmtExpr); 8044} 8045 8046ExprResult Sema::BuildBuiltinOffsetOf(SourceLocation BuiltinLoc, 8047 TypeSourceInfo *TInfo, 8048 OffsetOfComponent *CompPtr, 8049 unsigned NumComponents, 8050 SourceLocation RParenLoc) { 8051 QualType ArgTy = TInfo->getType(); 8052 bool Dependent = ArgTy->isDependentType(); 8053 SourceRange TypeRange = TInfo->getTypeLoc().getLocalSourceRange(); 8054 8055 // We must have at least one component that refers to the type, and the first 8056 // one is known to be a field designator. Verify that the ArgTy represents 8057 // a struct/union/class. 8058 if (!Dependent && !ArgTy->isRecordType()) 8059 return ExprError(Diag(BuiltinLoc, diag::err_offsetof_record_type) 8060 << ArgTy << TypeRange); 8061 8062 // Type must be complete per C99 7.17p3 because a declaring a variable 8063 // with an incomplete type would be ill-formed. 8064 if (!Dependent 8065 && RequireCompleteType(BuiltinLoc, ArgTy, 8066 PDiag(diag::err_offsetof_incomplete_type) 8067 << TypeRange)) 8068 return ExprError(); 8069 8070 // offsetof with non-identifier designators (e.g. "offsetof(x, a.b[c])") are a 8071 // GCC extension, diagnose them. 8072 // FIXME: This diagnostic isn't actually visible because the location is in 8073 // a system header! 8074 if (NumComponents != 1) 8075 Diag(BuiltinLoc, diag::ext_offsetof_extended_field_designator) 8076 << SourceRange(CompPtr[1].LocStart, CompPtr[NumComponents-1].LocEnd); 8077 8078 bool DidWarnAboutNonPOD = false; 8079 QualType CurrentType = ArgTy; 8080 typedef OffsetOfExpr::OffsetOfNode OffsetOfNode; 8081 llvm::SmallVector<OffsetOfNode, 4> Comps; 8082 llvm::SmallVector<Expr*, 4> Exprs; 8083 for (unsigned i = 0; i != NumComponents; ++i) { 8084 const OffsetOfComponent &OC = CompPtr[i]; 8085 if (OC.isBrackets) { 8086 // Offset of an array sub-field. TODO: Should we allow vector elements? 8087 if (!CurrentType->isDependentType()) { 8088 const ArrayType *AT = Context.getAsArrayType(CurrentType); 8089 if(!AT) 8090 return ExprError(Diag(OC.LocEnd, diag::err_offsetof_array_type) 8091 << CurrentType); 8092 CurrentType = AT->getElementType(); 8093 } else 8094 CurrentType = Context.DependentTy; 8095 8096 // The expression must be an integral expression. 8097 // FIXME: An integral constant expression? 8098 Expr *Idx = static_cast<Expr*>(OC.U.E); 8099 if (!Idx->isTypeDependent() && !Idx->isValueDependent() && 8100 !Idx->getType()->isIntegerType()) 8101 return ExprError(Diag(Idx->getLocStart(), 8102 diag::err_typecheck_subscript_not_integer) 8103 << Idx->getSourceRange()); 8104 8105 // Record this array index. 8106 Comps.push_back(OffsetOfNode(OC.LocStart, Exprs.size(), OC.LocEnd)); 8107 Exprs.push_back(Idx); 8108 continue; 8109 } 8110 8111 // Offset of a field. 8112 if (CurrentType->isDependentType()) { 8113 // We have the offset of a field, but we can't look into the dependent 8114 // type. Just record the identifier of the field. 8115 Comps.push_back(OffsetOfNode(OC.LocStart, OC.U.IdentInfo, OC.LocEnd)); 8116 CurrentType = Context.DependentTy; 8117 continue; 8118 } 8119 8120 // We need to have a complete type to look into. 8121 if (RequireCompleteType(OC.LocStart, CurrentType, 8122 diag::err_offsetof_incomplete_type)) 8123 return ExprError(); 8124 8125 // Look for the designated field. 8126 const RecordType *RC = CurrentType->getAs<RecordType>(); 8127 if (!RC) 8128 return ExprError(Diag(OC.LocEnd, diag::err_offsetof_record_type) 8129 << CurrentType); 8130 RecordDecl *RD = RC->getDecl(); 8131 8132 // C++ [lib.support.types]p5: 8133 // The macro offsetof accepts a restricted set of type arguments in this 8134 // International Standard. type shall be a POD structure or a POD union 8135 // (clause 9). 8136 if (CXXRecordDecl *CRD = dyn_cast<CXXRecordDecl>(RD)) { 8137 if (!CRD->isPOD() && !DidWarnAboutNonPOD && 8138 DiagRuntimeBehavior(BuiltinLoc, 0, 8139 PDiag(diag::warn_offsetof_non_pod_type) 8140 << SourceRange(CompPtr[0].LocStart, OC.LocEnd) 8141 << CurrentType)) 8142 DidWarnAboutNonPOD = true; 8143 } 8144 8145 // Look for the field. 8146 LookupResult R(*this, OC.U.IdentInfo, OC.LocStart, LookupMemberName); 8147 LookupQualifiedName(R, RD); 8148 FieldDecl *MemberDecl = R.getAsSingle<FieldDecl>(); 8149 IndirectFieldDecl *IndirectMemberDecl = 0; 8150 if (!MemberDecl) { 8151 if ((IndirectMemberDecl = R.getAsSingle<IndirectFieldDecl>())) 8152 MemberDecl = IndirectMemberDecl->getAnonField(); 8153 } 8154 8155 if (!MemberDecl) 8156 return ExprError(Diag(BuiltinLoc, diag::err_no_member) 8157 << OC.U.IdentInfo << RD << SourceRange(OC.LocStart, 8158 OC.LocEnd)); 8159 8160 // C99 7.17p3: 8161 // (If the specified member is a bit-field, the behavior is undefined.) 8162 // 8163 // We diagnose this as an error. 8164 if (MemberDecl->getBitWidth()) { 8165 Diag(OC.LocEnd, diag::err_offsetof_bitfield) 8166 << MemberDecl->getDeclName() 8167 << SourceRange(BuiltinLoc, RParenLoc); 8168 Diag(MemberDecl->getLocation(), diag::note_bitfield_decl); 8169 return ExprError(); 8170 } 8171 8172 RecordDecl *Parent = MemberDecl->getParent(); 8173 if (IndirectMemberDecl) 8174 Parent = cast<RecordDecl>(IndirectMemberDecl->getDeclContext()); 8175 8176 // If the member was found in a base class, introduce OffsetOfNodes for 8177 // the base class indirections. 8178 CXXBasePaths Paths(/*FindAmbiguities=*/true, /*RecordPaths=*/true, 8179 /*DetectVirtual=*/false); 8180 if (IsDerivedFrom(CurrentType, Context.getTypeDeclType(Parent), Paths)) { 8181 CXXBasePath &Path = Paths.front(); 8182 for (CXXBasePath::iterator B = Path.begin(), BEnd = Path.end(); 8183 B != BEnd; ++B) 8184 Comps.push_back(OffsetOfNode(B->Base)); 8185 } 8186 8187 if (IndirectMemberDecl) { 8188 for (IndirectFieldDecl::chain_iterator FI = 8189 IndirectMemberDecl->chain_begin(), 8190 FEnd = IndirectMemberDecl->chain_end(); FI != FEnd; FI++) { 8191 assert(isa<FieldDecl>(*FI)); 8192 Comps.push_back(OffsetOfNode(OC.LocStart, 8193 cast<FieldDecl>(*FI), OC.LocEnd)); 8194 } 8195 } else 8196 Comps.push_back(OffsetOfNode(OC.LocStart, MemberDecl, OC.LocEnd)); 8197 8198 CurrentType = MemberDecl->getType().getNonReferenceType(); 8199 } 8200 8201 return Owned(OffsetOfExpr::Create(Context, Context.getSizeType(), BuiltinLoc, 8202 TInfo, Comps.data(), Comps.size(), 8203 Exprs.data(), Exprs.size(), RParenLoc)); 8204} 8205 8206ExprResult Sema::ActOnBuiltinOffsetOf(Scope *S, 8207 SourceLocation BuiltinLoc, 8208 SourceLocation TypeLoc, 8209 ParsedType argty, 8210 OffsetOfComponent *CompPtr, 8211 unsigned NumComponents, 8212 SourceLocation RPLoc) { 8213 8214 TypeSourceInfo *ArgTInfo; 8215 QualType ArgTy = GetTypeFromParser(argty, &ArgTInfo); 8216 if (ArgTy.isNull()) 8217 return ExprError(); 8218 8219 if (!ArgTInfo) 8220 ArgTInfo = Context.getTrivialTypeSourceInfo(ArgTy, TypeLoc); 8221 8222 return BuildBuiltinOffsetOf(BuiltinLoc, ArgTInfo, CompPtr, NumComponents, 8223 RPLoc); 8224} 8225 8226 8227ExprResult Sema::ActOnChooseExpr(SourceLocation BuiltinLoc, 8228 Expr *CondExpr, 8229 Expr *LHSExpr, Expr *RHSExpr, 8230 SourceLocation RPLoc) { 8231 assert((CondExpr && LHSExpr && RHSExpr) && "Missing type argument(s)"); 8232 8233 ExprValueKind VK = VK_RValue; 8234 ExprObjectKind OK = OK_Ordinary; 8235 QualType resType; 8236 bool ValueDependent = false; 8237 if (CondExpr->isTypeDependent() || CondExpr->isValueDependent()) { 8238 resType = Context.DependentTy; 8239 ValueDependent = true; 8240 } else { 8241 // The conditional expression is required to be a constant expression. 8242 llvm::APSInt condEval(32); 8243 SourceLocation ExpLoc; 8244 if (!CondExpr->isIntegerConstantExpr(condEval, Context, &ExpLoc)) 8245 return ExprError(Diag(ExpLoc, 8246 diag::err_typecheck_choose_expr_requires_constant) 8247 << CondExpr->getSourceRange()); 8248 8249 // If the condition is > zero, then the AST type is the same as the LSHExpr. 8250 Expr *ActiveExpr = condEval.getZExtValue() ? LHSExpr : RHSExpr; 8251 8252 resType = ActiveExpr->getType(); 8253 ValueDependent = ActiveExpr->isValueDependent(); 8254 VK = ActiveExpr->getValueKind(); 8255 OK = ActiveExpr->getObjectKind(); 8256 } 8257 8258 return Owned(new (Context) ChooseExpr(BuiltinLoc, CondExpr, LHSExpr, RHSExpr, 8259 resType, VK, OK, RPLoc, 8260 resType->isDependentType(), 8261 ValueDependent)); 8262} 8263 8264//===----------------------------------------------------------------------===// 8265// Clang Extensions. 8266//===----------------------------------------------------------------------===// 8267 8268/// ActOnBlockStart - This callback is invoked when a block literal is started. 8269void Sema::ActOnBlockStart(SourceLocation CaretLoc, Scope *BlockScope) { 8270 BlockDecl *Block = BlockDecl::Create(Context, CurContext, CaretLoc); 8271 PushBlockScope(BlockScope, Block); 8272 CurContext->addDecl(Block); 8273 if (BlockScope) 8274 PushDeclContext(BlockScope, Block); 8275 else 8276 CurContext = Block; 8277} 8278 8279void Sema::ActOnBlockArguments(Declarator &ParamInfo, Scope *CurScope) { 8280 assert(ParamInfo.getIdentifier()==0 && "block-id should have no identifier!"); 8281 assert(ParamInfo.getContext() == Declarator::BlockLiteralContext); 8282 BlockScopeInfo *CurBlock = getCurBlock(); 8283 8284 TypeSourceInfo *Sig = GetTypeForDeclarator(ParamInfo, CurScope); 8285 QualType T = Sig->getType(); 8286 8287 // GetTypeForDeclarator always produces a function type for a block 8288 // literal signature. Furthermore, it is always a FunctionProtoType 8289 // unless the function was written with a typedef. 8290 assert(T->isFunctionType() && 8291 "GetTypeForDeclarator made a non-function block signature"); 8292 8293 // Look for an explicit signature in that function type. 8294 FunctionProtoTypeLoc ExplicitSignature; 8295 8296 TypeLoc tmp = Sig->getTypeLoc().IgnoreParens(); 8297 if (isa<FunctionProtoTypeLoc>(tmp)) { 8298 ExplicitSignature = cast<FunctionProtoTypeLoc>(tmp); 8299 8300 // Check whether that explicit signature was synthesized by 8301 // GetTypeForDeclarator. If so, don't save that as part of the 8302 // written signature. 8303 if (ExplicitSignature.getLocalRangeBegin() == 8304 ExplicitSignature.getLocalRangeEnd()) { 8305 // This would be much cheaper if we stored TypeLocs instead of 8306 // TypeSourceInfos. 8307 TypeLoc Result = ExplicitSignature.getResultLoc(); 8308 unsigned Size = Result.getFullDataSize(); 8309 Sig = Context.CreateTypeSourceInfo(Result.getType(), Size); 8310 Sig->getTypeLoc().initializeFullCopy(Result, Size); 8311 8312 ExplicitSignature = FunctionProtoTypeLoc(); 8313 } 8314 } 8315 8316 CurBlock->TheDecl->setSignatureAsWritten(Sig); 8317 CurBlock->FunctionType = T; 8318 8319 const FunctionType *Fn = T->getAs<FunctionType>(); 8320 QualType RetTy = Fn->getResultType(); 8321 bool isVariadic = 8322 (isa<FunctionProtoType>(Fn) && cast<FunctionProtoType>(Fn)->isVariadic()); 8323 8324 CurBlock->TheDecl->setIsVariadic(isVariadic); 8325 8326 // Don't allow returning a objc interface by value. 8327 if (RetTy->isObjCObjectType()) { 8328 Diag(ParamInfo.getSourceRange().getBegin(), 8329 diag::err_object_cannot_be_passed_returned_by_value) << 0 << RetTy; 8330 return; 8331 } 8332 8333 // Context.DependentTy is used as a placeholder for a missing block 8334 // return type. TODO: what should we do with declarators like: 8335 // ^ * { ... } 8336 // If the answer is "apply template argument deduction".... 8337 if (RetTy != Context.DependentTy) 8338 CurBlock->ReturnType = RetTy; 8339 8340 // Push block parameters from the declarator if we had them. 8341 llvm::SmallVector<ParmVarDecl*, 8> Params; 8342 if (ExplicitSignature) { 8343 for (unsigned I = 0, E = ExplicitSignature.getNumArgs(); I != E; ++I) { 8344 ParmVarDecl *Param = ExplicitSignature.getArg(I); 8345 if (Param->getIdentifier() == 0 && 8346 !Param->isImplicit() && 8347 !Param->isInvalidDecl() && 8348 !getLangOptions().CPlusPlus) 8349 Diag(Param->getLocation(), diag::err_parameter_name_omitted); 8350 Params.push_back(Param); 8351 } 8352 8353 // Fake up parameter variables if we have a typedef, like 8354 // ^ fntype { ... } 8355 } else if (const FunctionProtoType *Fn = T->getAs<FunctionProtoType>()) { 8356 for (FunctionProtoType::arg_type_iterator 8357 I = Fn->arg_type_begin(), E = Fn->arg_type_end(); I != E; ++I) { 8358 ParmVarDecl *Param = 8359 BuildParmVarDeclForTypedef(CurBlock->TheDecl, 8360 ParamInfo.getSourceRange().getBegin(), 8361 *I); 8362 Params.push_back(Param); 8363 } 8364 } 8365 8366 // Set the parameters on the block decl. 8367 if (!Params.empty()) { 8368 CurBlock->TheDecl->setParams(Params.data(), Params.size()); 8369 CheckParmsForFunctionDef(CurBlock->TheDecl->param_begin(), 8370 CurBlock->TheDecl->param_end(), 8371 /*CheckParameterNames=*/false); 8372 } 8373 8374 // Finally we can process decl attributes. 8375 ProcessDeclAttributes(CurScope, CurBlock->TheDecl, ParamInfo); 8376 8377 if (!isVariadic && CurBlock->TheDecl->getAttr<SentinelAttr>()) { 8378 Diag(ParamInfo.getAttributes()->getLoc(), 8379 diag::warn_attribute_sentinel_not_variadic) << 1; 8380 // FIXME: remove the attribute. 8381 } 8382 8383 // Put the parameter variables in scope. We can bail out immediately 8384 // if we don't have any. 8385 if (Params.empty()) 8386 return; 8387 8388 for (BlockDecl::param_iterator AI = CurBlock->TheDecl->param_begin(), 8389 E = CurBlock->TheDecl->param_end(); AI != E; ++AI) { 8390 (*AI)->setOwningFunction(CurBlock->TheDecl); 8391 8392 // If this has an identifier, add it to the scope stack. 8393 if ((*AI)->getIdentifier()) { 8394 CheckShadow(CurBlock->TheScope, *AI); 8395 8396 PushOnScopeChains(*AI, CurBlock->TheScope); 8397 } 8398 } 8399} 8400 8401/// ActOnBlockError - If there is an error parsing a block, this callback 8402/// is invoked to pop the information about the block from the action impl. 8403void Sema::ActOnBlockError(SourceLocation CaretLoc, Scope *CurScope) { 8404 // Pop off CurBlock, handle nested blocks. 8405 PopDeclContext(); 8406 PopFunctionOrBlockScope(); 8407} 8408 8409/// ActOnBlockStmtExpr - This is called when the body of a block statement 8410/// literal was successfully completed. ^(int x){...} 8411ExprResult Sema::ActOnBlockStmtExpr(SourceLocation CaretLoc, 8412 Stmt *Body, Scope *CurScope) { 8413 // If blocks are disabled, emit an error. 8414 if (!LangOpts.Blocks) 8415 Diag(CaretLoc, diag::err_blocks_disable); 8416 8417 BlockScopeInfo *BSI = cast<BlockScopeInfo>(FunctionScopes.back()); 8418 8419 PopDeclContext(); 8420 8421 QualType RetTy = Context.VoidTy; 8422 if (!BSI->ReturnType.isNull()) 8423 RetTy = BSI->ReturnType; 8424 8425 bool NoReturn = BSI->TheDecl->getAttr<NoReturnAttr>(); 8426 QualType BlockTy; 8427 8428 // Set the captured variables on the block. 8429 BSI->TheDecl->setCaptures(Context, BSI->Captures.begin(), BSI->Captures.end(), 8430 BSI->CapturesCXXThis); 8431 8432 // If the user wrote a function type in some form, try to use that. 8433 if (!BSI->FunctionType.isNull()) { 8434 const FunctionType *FTy = BSI->FunctionType->getAs<FunctionType>(); 8435 8436 FunctionType::ExtInfo Ext = FTy->getExtInfo(); 8437 if (NoReturn && !Ext.getNoReturn()) Ext = Ext.withNoReturn(true); 8438 8439 // Turn protoless block types into nullary block types. 8440 if (isa<FunctionNoProtoType>(FTy)) { 8441 FunctionProtoType::ExtProtoInfo EPI; 8442 EPI.ExtInfo = Ext; 8443 BlockTy = Context.getFunctionType(RetTy, 0, 0, EPI); 8444 8445 // Otherwise, if we don't need to change anything about the function type, 8446 // preserve its sugar structure. 8447 } else if (FTy->getResultType() == RetTy && 8448 (!NoReturn || FTy->getNoReturnAttr())) { 8449 BlockTy = BSI->FunctionType; 8450 8451 // Otherwise, make the minimal modifications to the function type. 8452 } else { 8453 const FunctionProtoType *FPT = cast<FunctionProtoType>(FTy); 8454 FunctionProtoType::ExtProtoInfo EPI = FPT->getExtProtoInfo(); 8455 EPI.TypeQuals = 0; // FIXME: silently? 8456 EPI.ExtInfo = Ext; 8457 BlockTy = Context.getFunctionType(RetTy, 8458 FPT->arg_type_begin(), 8459 FPT->getNumArgs(), 8460 EPI); 8461 } 8462 8463 // If we don't have a function type, just build one from nothing. 8464 } else { 8465 FunctionProtoType::ExtProtoInfo EPI; 8466 EPI.ExtInfo = FunctionType::ExtInfo().withNoReturn(NoReturn); 8467 BlockTy = Context.getFunctionType(RetTy, 0, 0, EPI); 8468 } 8469 8470 DiagnoseUnusedParameters(BSI->TheDecl->param_begin(), 8471 BSI->TheDecl->param_end()); 8472 BlockTy = Context.getBlockPointerType(BlockTy); 8473 8474 // If needed, diagnose invalid gotos and switches in the block. 8475 if (getCurFunction()->NeedsScopeChecking() && 8476 !hasAnyUnrecoverableErrorsInThisFunction()) 8477 DiagnoseInvalidJumps(cast<CompoundStmt>(Body)); 8478 8479 BSI->TheDecl->setBody(cast<CompoundStmt>(Body)); 8480 8481 for (BlockDecl::capture_const_iterator ci = BSI->TheDecl->capture_begin(), 8482 ce = BSI->TheDecl->capture_end(); ci != ce; ++ci) { 8483 const VarDecl *variable = ci->getVariable(); 8484 QualType T = variable->getType(); 8485 QualType::DestructionKind destructKind = T.isDestructedType(); 8486 if (destructKind != QualType::DK_none) 8487 getCurFunction()->setHasBranchProtectedScope(); 8488 } 8489 8490 BlockExpr *Result = new (Context) BlockExpr(BSI->TheDecl, BlockTy); 8491 const AnalysisBasedWarnings::Policy &WP = AnalysisWarnings.getDefaultPolicy(); 8492 PopFunctionOrBlockScope(&WP, Result->getBlockDecl(), Result); 8493 8494 return Owned(Result); 8495} 8496 8497ExprResult Sema::ActOnVAArg(SourceLocation BuiltinLoc, 8498 Expr *expr, ParsedType type, 8499 SourceLocation RPLoc) { 8500 TypeSourceInfo *TInfo; 8501 GetTypeFromParser(type, &TInfo); 8502 return BuildVAArgExpr(BuiltinLoc, expr, TInfo, RPLoc); 8503} 8504 8505ExprResult Sema::BuildVAArgExpr(SourceLocation BuiltinLoc, 8506 Expr *E, TypeSourceInfo *TInfo, 8507 SourceLocation RPLoc) { 8508 Expr *OrigExpr = E; 8509 8510 // Get the va_list type 8511 QualType VaListType = Context.getBuiltinVaListType(); 8512 if (VaListType->isArrayType()) { 8513 // Deal with implicit array decay; for example, on x86-64, 8514 // va_list is an array, but it's supposed to decay to 8515 // a pointer for va_arg. 8516 VaListType = Context.getArrayDecayedType(VaListType); 8517 // Make sure the input expression also decays appropriately. 8518 ExprResult Result = UsualUnaryConversions(E); 8519 if (Result.isInvalid()) 8520 return ExprError(); 8521 E = Result.take(); 8522 } else { 8523 // Otherwise, the va_list argument must be an l-value because 8524 // it is modified by va_arg. 8525 if (!E->isTypeDependent() && 8526 CheckForModifiableLvalue(E, BuiltinLoc, *this)) 8527 return ExprError(); 8528 } 8529 8530 if (!E->isTypeDependent() && 8531 !Context.hasSameType(VaListType, E->getType())) { 8532 return ExprError(Diag(E->getLocStart(), 8533 diag::err_first_argument_to_va_arg_not_of_type_va_list) 8534 << OrigExpr->getType() << E->getSourceRange()); 8535 } 8536 8537 if (!TInfo->getType()->isDependentType()) { 8538 if (RequireCompleteType(TInfo->getTypeLoc().getBeginLoc(), TInfo->getType(), 8539 PDiag(diag::err_second_parameter_to_va_arg_incomplete) 8540 << TInfo->getTypeLoc().getSourceRange())) 8541 return ExprError(); 8542 8543 if (RequireNonAbstractType(TInfo->getTypeLoc().getBeginLoc(), 8544 TInfo->getType(), 8545 PDiag(diag::err_second_parameter_to_va_arg_abstract) 8546 << TInfo->getTypeLoc().getSourceRange())) 8547 return ExprError(); 8548 8549 if (!TInfo->getType().isPODType(Context)) 8550 Diag(TInfo->getTypeLoc().getBeginLoc(), 8551 diag::warn_second_parameter_to_va_arg_not_pod) 8552 << TInfo->getType() 8553 << TInfo->getTypeLoc().getSourceRange(); 8554 8555 // Check for va_arg where arguments of the given type will be promoted 8556 // (i.e. this va_arg is guaranteed to have undefined behavior). 8557 QualType PromoteType; 8558 if (TInfo->getType()->isPromotableIntegerType()) { 8559 PromoteType = Context.getPromotedIntegerType(TInfo->getType()); 8560 if (Context.typesAreCompatible(PromoteType, TInfo->getType())) 8561 PromoteType = QualType(); 8562 } 8563 if (TInfo->getType()->isSpecificBuiltinType(BuiltinType::Float)) 8564 PromoteType = Context.DoubleTy; 8565 if (!PromoteType.isNull()) 8566 Diag(TInfo->getTypeLoc().getBeginLoc(), 8567 diag::warn_second_parameter_to_va_arg_never_compatible) 8568 << TInfo->getType() 8569 << PromoteType 8570 << TInfo->getTypeLoc().getSourceRange(); 8571 } 8572 8573 QualType T = TInfo->getType().getNonLValueExprType(Context); 8574 return Owned(new (Context) VAArgExpr(BuiltinLoc, E, TInfo, RPLoc, T)); 8575} 8576 8577ExprResult Sema::ActOnGNUNullExpr(SourceLocation TokenLoc) { 8578 // The type of __null will be int or long, depending on the size of 8579 // pointers on the target. 8580 QualType Ty; 8581 unsigned pw = Context.Target.getPointerWidth(0); 8582 if (pw == Context.Target.getIntWidth()) 8583 Ty = Context.IntTy; 8584 else if (pw == Context.Target.getLongWidth()) 8585 Ty = Context.LongTy; 8586 else if (pw == Context.Target.getLongLongWidth()) 8587 Ty = Context.LongLongTy; 8588 else { 8589 assert(!"I don't know size of pointer!"); 8590 Ty = Context.IntTy; 8591 } 8592 8593 return Owned(new (Context) GNUNullExpr(Ty, TokenLoc)); 8594} 8595 8596static void MakeObjCStringLiteralFixItHint(Sema& SemaRef, QualType DstType, 8597 Expr *SrcExpr, FixItHint &Hint) { 8598 if (!SemaRef.getLangOptions().ObjC1) 8599 return; 8600 8601 const ObjCObjectPointerType *PT = DstType->getAs<ObjCObjectPointerType>(); 8602 if (!PT) 8603 return; 8604 8605 // Check if the destination is of type 'id'. 8606 if (!PT->isObjCIdType()) { 8607 // Check if the destination is the 'NSString' interface. 8608 const ObjCInterfaceDecl *ID = PT->getInterfaceDecl(); 8609 if (!ID || !ID->getIdentifier()->isStr("NSString")) 8610 return; 8611 } 8612 8613 // Strip off any parens and casts. 8614 StringLiteral *SL = dyn_cast<StringLiteral>(SrcExpr->IgnoreParenCasts()); 8615 if (!SL || SL->isWide()) 8616 return; 8617 8618 Hint = FixItHint::CreateInsertion(SL->getLocStart(), "@"); 8619} 8620 8621bool Sema::DiagnoseAssignmentResult(AssignConvertType ConvTy, 8622 SourceLocation Loc, 8623 QualType DstType, QualType SrcType, 8624 Expr *SrcExpr, AssignmentAction Action, 8625 bool *Complained) { 8626 if (Complained) 8627 *Complained = false; 8628 8629 // Decode the result (notice that AST's are still created for extensions). 8630 bool CheckInferredResultType = false; 8631 bool isInvalid = false; 8632 unsigned DiagKind; 8633 FixItHint Hint; 8634 8635 switch (ConvTy) { 8636 default: assert(0 && "Unknown conversion type"); 8637 case Compatible: return false; 8638 case PointerToInt: 8639 DiagKind = diag::ext_typecheck_convert_pointer_int; 8640 break; 8641 case IntToPointer: 8642 DiagKind = diag::ext_typecheck_convert_int_pointer; 8643 break; 8644 case IncompatiblePointer: 8645 MakeObjCStringLiteralFixItHint(*this, DstType, SrcExpr, Hint); 8646 DiagKind = diag::ext_typecheck_convert_incompatible_pointer; 8647 CheckInferredResultType = DstType->isObjCObjectPointerType() && 8648 SrcType->isObjCObjectPointerType(); 8649 break; 8650 case IncompatiblePointerSign: 8651 DiagKind = diag::ext_typecheck_convert_incompatible_pointer_sign; 8652 break; 8653 case FunctionVoidPointer: 8654 DiagKind = diag::ext_typecheck_convert_pointer_void_func; 8655 break; 8656 case IncompatiblePointerDiscardsQualifiers: { 8657 // Perform array-to-pointer decay if necessary. 8658 if (SrcType->isArrayType()) SrcType = Context.getArrayDecayedType(SrcType); 8659 8660 Qualifiers lhq = SrcType->getPointeeType().getQualifiers(); 8661 Qualifiers rhq = DstType->getPointeeType().getQualifiers(); 8662 if (lhq.getAddressSpace() != rhq.getAddressSpace()) { 8663 DiagKind = diag::err_typecheck_incompatible_address_space; 8664 break; 8665 8666 8667 } else if (lhq.getObjCLifetime() != rhq.getObjCLifetime()) { 8668 DiagKind = diag::err_typecheck_incompatible_ownership; 8669 break; 8670 } 8671 8672 llvm_unreachable("unknown error case for discarding qualifiers!"); 8673 // fallthrough 8674 } 8675 case CompatiblePointerDiscardsQualifiers: 8676 // If the qualifiers lost were because we were applying the 8677 // (deprecated) C++ conversion from a string literal to a char* 8678 // (or wchar_t*), then there was no error (C++ 4.2p2). FIXME: 8679 // Ideally, this check would be performed in 8680 // checkPointerTypesForAssignment. However, that would require a 8681 // bit of refactoring (so that the second argument is an 8682 // expression, rather than a type), which should be done as part 8683 // of a larger effort to fix checkPointerTypesForAssignment for 8684 // C++ semantics. 8685 if (getLangOptions().CPlusPlus && 8686 IsStringLiteralToNonConstPointerConversion(SrcExpr, DstType)) 8687 return false; 8688 DiagKind = diag::ext_typecheck_convert_discards_qualifiers; 8689 break; 8690 case IncompatibleNestedPointerQualifiers: 8691 DiagKind = diag::ext_nested_pointer_qualifier_mismatch; 8692 break; 8693 case IntToBlockPointer: 8694 DiagKind = diag::err_int_to_block_pointer; 8695 break; 8696 case IncompatibleBlockPointer: 8697 DiagKind = diag::err_typecheck_convert_incompatible_block_pointer; 8698 break; 8699 case IncompatibleObjCQualifiedId: 8700 // FIXME: Diagnose the problem in ObjCQualifiedIdTypesAreCompatible, since 8701 // it can give a more specific diagnostic. 8702 DiagKind = diag::warn_incompatible_qualified_id; 8703 break; 8704 case IncompatibleVectors: 8705 DiagKind = diag::warn_incompatible_vectors; 8706 break; 8707 case IncompatibleObjCWeakRef: 8708 DiagKind = diag::err_arc_weak_unavailable_assign; 8709 break; 8710 case Incompatible: 8711 DiagKind = diag::err_typecheck_convert_incompatible; 8712 isInvalid = true; 8713 break; 8714 } 8715 8716 QualType FirstType, SecondType; 8717 switch (Action) { 8718 case AA_Assigning: 8719 case AA_Initializing: 8720 // The destination type comes first. 8721 FirstType = DstType; 8722 SecondType = SrcType; 8723 break; 8724 8725 case AA_Returning: 8726 case AA_Passing: 8727 case AA_Converting: 8728 case AA_Sending: 8729 case AA_Casting: 8730 // The source type comes first. 8731 FirstType = SrcType; 8732 SecondType = DstType; 8733 break; 8734 } 8735 8736 Diag(Loc, DiagKind) << FirstType << SecondType << Action 8737 << SrcExpr->getSourceRange() << Hint; 8738 if (CheckInferredResultType) 8739 EmitRelatedResultTypeNote(SrcExpr); 8740 8741 if (Complained) 8742 *Complained = true; 8743 return isInvalid; 8744} 8745 8746bool Sema::VerifyIntegerConstantExpression(const Expr *E, llvm::APSInt *Result){ 8747 llvm::APSInt ICEResult; 8748 if (E->isIntegerConstantExpr(ICEResult, Context)) { 8749 if (Result) 8750 *Result = ICEResult; 8751 return false; 8752 } 8753 8754 Expr::EvalResult EvalResult; 8755 8756 if (!E->Evaluate(EvalResult, Context) || !EvalResult.Val.isInt() || 8757 EvalResult.HasSideEffects) { 8758 Diag(E->getExprLoc(), diag::err_expr_not_ice) << E->getSourceRange(); 8759 8760 if (EvalResult.Diag) { 8761 // We only show the note if it's not the usual "invalid subexpression" 8762 // or if it's actually in a subexpression. 8763 if (EvalResult.Diag != diag::note_invalid_subexpr_in_ice || 8764 E->IgnoreParens() != EvalResult.DiagExpr->IgnoreParens()) 8765 Diag(EvalResult.DiagLoc, EvalResult.Diag); 8766 } 8767 8768 return true; 8769 } 8770 8771 Diag(E->getExprLoc(), diag::ext_expr_not_ice) << 8772 E->getSourceRange(); 8773 8774 if (EvalResult.Diag && 8775 Diags.getDiagnosticLevel(diag::ext_expr_not_ice, EvalResult.DiagLoc) 8776 != Diagnostic::Ignored) 8777 Diag(EvalResult.DiagLoc, EvalResult.Diag); 8778 8779 if (Result) 8780 *Result = EvalResult.Val.getInt(); 8781 return false; 8782} 8783 8784void 8785Sema::PushExpressionEvaluationContext(ExpressionEvaluationContext NewContext) { 8786 ExprEvalContexts.push_back( 8787 ExpressionEvaluationContextRecord(NewContext, 8788 ExprTemporaries.size(), 8789 ExprNeedsCleanups)); 8790 ExprNeedsCleanups = false; 8791} 8792 8793void 8794Sema::PopExpressionEvaluationContext() { 8795 // Pop the current expression evaluation context off the stack. 8796 ExpressionEvaluationContextRecord Rec = ExprEvalContexts.back(); 8797 ExprEvalContexts.pop_back(); 8798 8799 if (Rec.Context == PotentiallyPotentiallyEvaluated) { 8800 if (Rec.PotentiallyReferenced) { 8801 // Mark any remaining declarations in the current position of the stack 8802 // as "referenced". If they were not meant to be referenced, semantic 8803 // analysis would have eliminated them (e.g., in ActOnCXXTypeId). 8804 for (PotentiallyReferencedDecls::iterator 8805 I = Rec.PotentiallyReferenced->begin(), 8806 IEnd = Rec.PotentiallyReferenced->end(); 8807 I != IEnd; ++I) 8808 MarkDeclarationReferenced(I->first, I->second); 8809 } 8810 8811 if (Rec.PotentiallyDiagnosed) { 8812 // Emit any pending diagnostics. 8813 for (PotentiallyEmittedDiagnostics::iterator 8814 I = Rec.PotentiallyDiagnosed->begin(), 8815 IEnd = Rec.PotentiallyDiagnosed->end(); 8816 I != IEnd; ++I) 8817 Diag(I->first, I->second); 8818 } 8819 } 8820 8821 // When are coming out of an unevaluated context, clear out any 8822 // temporaries that we may have created as part of the evaluation of 8823 // the expression in that context: they aren't relevant because they 8824 // will never be constructed. 8825 if (Rec.Context == Unevaluated) { 8826 ExprTemporaries.erase(ExprTemporaries.begin() + Rec.NumTemporaries, 8827 ExprTemporaries.end()); 8828 ExprNeedsCleanups = Rec.ParentNeedsCleanups; 8829 8830 // Otherwise, merge the contexts together. 8831 } else { 8832 ExprNeedsCleanups |= Rec.ParentNeedsCleanups; 8833 } 8834 8835 // Destroy the popped expression evaluation record. 8836 Rec.Destroy(); 8837} 8838 8839void Sema::DiscardCleanupsInEvaluationContext() { 8840 ExprTemporaries.erase( 8841 ExprTemporaries.begin() + ExprEvalContexts.back().NumTemporaries, 8842 ExprTemporaries.end()); 8843 ExprNeedsCleanups = false; 8844} 8845 8846/// \brief Note that the given declaration was referenced in the source code. 8847/// 8848/// This routine should be invoke whenever a given declaration is referenced 8849/// in the source code, and where that reference occurred. If this declaration 8850/// reference means that the the declaration is used (C++ [basic.def.odr]p2, 8851/// C99 6.9p3), then the declaration will be marked as used. 8852/// 8853/// \param Loc the location where the declaration was referenced. 8854/// 8855/// \param D the declaration that has been referenced by the source code. 8856void Sema::MarkDeclarationReferenced(SourceLocation Loc, Decl *D) { 8857 assert(D && "No declaration?"); 8858 8859 D->setReferenced(); 8860 8861 if (D->isUsed(false)) 8862 return; 8863 8864 // Mark a parameter or variable declaration "used", regardless of whether we're in a 8865 // template or not. The reason for this is that unevaluated expressions 8866 // (e.g. (void)sizeof()) constitute a use for warning purposes (-Wunused-variables and 8867 // -Wunused-parameters) 8868 if (isa<ParmVarDecl>(D) || 8869 (isa<VarDecl>(D) && D->getDeclContext()->isFunctionOrMethod())) { 8870 D->setUsed(); 8871 return; 8872 } 8873 8874 if (!isa<VarDecl>(D) && !isa<FunctionDecl>(D)) 8875 return; 8876 8877 // Do not mark anything as "used" within a dependent context; wait for 8878 // an instantiation. 8879 if (CurContext->isDependentContext()) 8880 return; 8881 8882 switch (ExprEvalContexts.back().Context) { 8883 case Unevaluated: 8884 // We are in an expression that is not potentially evaluated; do nothing. 8885 return; 8886 8887 case PotentiallyEvaluated: 8888 // We are in a potentially-evaluated expression, so this declaration is 8889 // "used"; handle this below. 8890 break; 8891 8892 case PotentiallyPotentiallyEvaluated: 8893 // We are in an expression that may be potentially evaluated; queue this 8894 // declaration reference until we know whether the expression is 8895 // potentially evaluated. 8896 ExprEvalContexts.back().addReferencedDecl(Loc, D); 8897 return; 8898 8899 case PotentiallyEvaluatedIfUsed: 8900 // Referenced declarations will only be used if the construct in the 8901 // containing expression is used. 8902 return; 8903 } 8904 8905 // Note that this declaration has been used. 8906 if (CXXConstructorDecl *Constructor = dyn_cast<CXXConstructorDecl>(D)) { 8907 if (Constructor->isDefaulted() && Constructor->isDefaultConstructor()) { 8908 if (Constructor->isTrivial()) 8909 return; 8910 if (!Constructor->isUsed(false)) 8911 DefineImplicitDefaultConstructor(Loc, Constructor); 8912 } else if (Constructor->isDefaulted() && 8913 Constructor->isCopyConstructor()) { 8914 if (!Constructor->isUsed(false)) 8915 DefineImplicitCopyConstructor(Loc, Constructor); 8916 } 8917 8918 MarkVTableUsed(Loc, Constructor->getParent()); 8919 } else if (CXXDestructorDecl *Destructor = dyn_cast<CXXDestructorDecl>(D)) { 8920 if (Destructor->isDefaulted() && !Destructor->isUsed(false)) 8921 DefineImplicitDestructor(Loc, Destructor); 8922 if (Destructor->isVirtual()) 8923 MarkVTableUsed(Loc, Destructor->getParent()); 8924 } else if (CXXMethodDecl *MethodDecl = dyn_cast<CXXMethodDecl>(D)) { 8925 if (MethodDecl->isDefaulted() && MethodDecl->isOverloadedOperator() && 8926 MethodDecl->getOverloadedOperator() == OO_Equal) { 8927 if (!MethodDecl->isUsed(false)) 8928 DefineImplicitCopyAssignment(Loc, MethodDecl); 8929 } else if (MethodDecl->isVirtual()) 8930 MarkVTableUsed(Loc, MethodDecl->getParent()); 8931 } 8932 if (FunctionDecl *Function = dyn_cast<FunctionDecl>(D)) { 8933 // Recursive functions should be marked when used from another function. 8934 if (CurContext == Function) return; 8935 8936 // Implicit instantiation of function templates and member functions of 8937 // class templates. 8938 if (Function->isImplicitlyInstantiable()) { 8939 bool AlreadyInstantiated = false; 8940 if (FunctionTemplateSpecializationInfo *SpecInfo 8941 = Function->getTemplateSpecializationInfo()) { 8942 if (SpecInfo->getPointOfInstantiation().isInvalid()) 8943 SpecInfo->setPointOfInstantiation(Loc); 8944 else if (SpecInfo->getTemplateSpecializationKind() 8945 == TSK_ImplicitInstantiation) 8946 AlreadyInstantiated = true; 8947 } else if (MemberSpecializationInfo *MSInfo 8948 = Function->getMemberSpecializationInfo()) { 8949 if (MSInfo->getPointOfInstantiation().isInvalid()) 8950 MSInfo->setPointOfInstantiation(Loc); 8951 else if (MSInfo->getTemplateSpecializationKind() 8952 == TSK_ImplicitInstantiation) 8953 AlreadyInstantiated = true; 8954 } 8955 8956 if (!AlreadyInstantiated) { 8957 if (isa<CXXRecordDecl>(Function->getDeclContext()) && 8958 cast<CXXRecordDecl>(Function->getDeclContext())->isLocalClass()) 8959 PendingLocalImplicitInstantiations.push_back(std::make_pair(Function, 8960 Loc)); 8961 else 8962 PendingInstantiations.push_back(std::make_pair(Function, Loc)); 8963 } 8964 } else { 8965 // Walk redefinitions, as some of them may be instantiable. 8966 for (FunctionDecl::redecl_iterator i(Function->redecls_begin()), 8967 e(Function->redecls_end()); i != e; ++i) { 8968 if (!i->isUsed(false) && i->isImplicitlyInstantiable()) 8969 MarkDeclarationReferenced(Loc, *i); 8970 } 8971 } 8972 8973 // Keep track of used but undefined functions. 8974 if (!Function->isPure() && !Function->hasBody() && 8975 Function->getLinkage() != ExternalLinkage) { 8976 SourceLocation &old = UndefinedInternals[Function->getCanonicalDecl()]; 8977 if (old.isInvalid()) old = Loc; 8978 } 8979 8980 Function->setUsed(true); 8981 return; 8982 } 8983 8984 if (VarDecl *Var = dyn_cast<VarDecl>(D)) { 8985 // Implicit instantiation of static data members of class templates. 8986 if (Var->isStaticDataMember() && 8987 Var->getInstantiatedFromStaticDataMember()) { 8988 MemberSpecializationInfo *MSInfo = Var->getMemberSpecializationInfo(); 8989 assert(MSInfo && "Missing member specialization information?"); 8990 if (MSInfo->getPointOfInstantiation().isInvalid() && 8991 MSInfo->getTemplateSpecializationKind()== TSK_ImplicitInstantiation) { 8992 MSInfo->setPointOfInstantiation(Loc); 8993 // This is a modification of an existing AST node. Notify listeners. 8994 if (ASTMutationListener *L = getASTMutationListener()) 8995 L->StaticDataMemberInstantiated(Var); 8996 PendingInstantiations.push_back(std::make_pair(Var, Loc)); 8997 } 8998 } 8999 9000 // Keep track of used but undefined variables. We make a hole in 9001 // the warning for static const data members with in-line 9002 // initializers. 9003 if (Var->hasDefinition() == VarDecl::DeclarationOnly 9004 && Var->getLinkage() != ExternalLinkage 9005 && !(Var->isStaticDataMember() && Var->hasInit())) { 9006 SourceLocation &old = UndefinedInternals[Var->getCanonicalDecl()]; 9007 if (old.isInvalid()) old = Loc; 9008 } 9009 9010 D->setUsed(true); 9011 return; 9012 } 9013} 9014 9015namespace { 9016 // Mark all of the declarations referenced 9017 // FIXME: Not fully implemented yet! We need to have a better understanding 9018 // of when we're entering 9019 class MarkReferencedDecls : public RecursiveASTVisitor<MarkReferencedDecls> { 9020 Sema &S; 9021 SourceLocation Loc; 9022 9023 public: 9024 typedef RecursiveASTVisitor<MarkReferencedDecls> Inherited; 9025 9026 MarkReferencedDecls(Sema &S, SourceLocation Loc) : S(S), Loc(Loc) { } 9027 9028 bool TraverseTemplateArgument(const TemplateArgument &Arg); 9029 bool TraverseRecordType(RecordType *T); 9030 }; 9031} 9032 9033bool MarkReferencedDecls::TraverseTemplateArgument( 9034 const TemplateArgument &Arg) { 9035 if (Arg.getKind() == TemplateArgument::Declaration) { 9036 S.MarkDeclarationReferenced(Loc, Arg.getAsDecl()); 9037 } 9038 9039 return Inherited::TraverseTemplateArgument(Arg); 9040} 9041 9042bool MarkReferencedDecls::TraverseRecordType(RecordType *T) { 9043 if (ClassTemplateSpecializationDecl *Spec 9044 = dyn_cast<ClassTemplateSpecializationDecl>(T->getDecl())) { 9045 const TemplateArgumentList &Args = Spec->getTemplateArgs(); 9046 return TraverseTemplateArguments(Args.data(), Args.size()); 9047 } 9048 9049 return true; 9050} 9051 9052void Sema::MarkDeclarationsReferencedInType(SourceLocation Loc, QualType T) { 9053 MarkReferencedDecls Marker(*this, Loc); 9054 Marker.TraverseType(Context.getCanonicalType(T)); 9055} 9056 9057namespace { 9058 /// \brief Helper class that marks all of the declarations referenced by 9059 /// potentially-evaluated subexpressions as "referenced". 9060 class EvaluatedExprMarker : public EvaluatedExprVisitor<EvaluatedExprMarker> { 9061 Sema &S; 9062 9063 public: 9064 typedef EvaluatedExprVisitor<EvaluatedExprMarker> Inherited; 9065 9066 explicit EvaluatedExprMarker(Sema &S) : Inherited(S.Context), S(S) { } 9067 9068 void VisitDeclRefExpr(DeclRefExpr *E) { 9069 S.MarkDeclarationReferenced(E->getLocation(), E->getDecl()); 9070 } 9071 9072 void VisitMemberExpr(MemberExpr *E) { 9073 S.MarkDeclarationReferenced(E->getMemberLoc(), E->getMemberDecl()); 9074 Inherited::VisitMemberExpr(E); 9075 } 9076 9077 void VisitCXXNewExpr(CXXNewExpr *E) { 9078 if (E->getConstructor()) 9079 S.MarkDeclarationReferenced(E->getLocStart(), E->getConstructor()); 9080 if (E->getOperatorNew()) 9081 S.MarkDeclarationReferenced(E->getLocStart(), E->getOperatorNew()); 9082 if (E->getOperatorDelete()) 9083 S.MarkDeclarationReferenced(E->getLocStart(), E->getOperatorDelete()); 9084 Inherited::VisitCXXNewExpr(E); 9085 } 9086 9087 void VisitCXXDeleteExpr(CXXDeleteExpr *E) { 9088 if (E->getOperatorDelete()) 9089 S.MarkDeclarationReferenced(E->getLocStart(), E->getOperatorDelete()); 9090 QualType Destroyed = S.Context.getBaseElementType(E->getDestroyedType()); 9091 if (const RecordType *DestroyedRec = Destroyed->getAs<RecordType>()) { 9092 CXXRecordDecl *Record = cast<CXXRecordDecl>(DestroyedRec->getDecl()); 9093 S.MarkDeclarationReferenced(E->getLocStart(), 9094 S.LookupDestructor(Record)); 9095 } 9096 9097 Inherited::VisitCXXDeleteExpr(E); 9098 } 9099 9100 void VisitCXXConstructExpr(CXXConstructExpr *E) { 9101 S.MarkDeclarationReferenced(E->getLocStart(), E->getConstructor()); 9102 Inherited::VisitCXXConstructExpr(E); 9103 } 9104 9105 void VisitBlockDeclRefExpr(BlockDeclRefExpr *E) { 9106 S.MarkDeclarationReferenced(E->getLocation(), E->getDecl()); 9107 } 9108 9109 void VisitCXXDefaultArgExpr(CXXDefaultArgExpr *E) { 9110 Visit(E->getExpr()); 9111 } 9112 }; 9113} 9114 9115/// \brief Mark any declarations that appear within this expression or any 9116/// potentially-evaluated subexpressions as "referenced". 9117void Sema::MarkDeclarationsReferencedInExpr(Expr *E) { 9118 EvaluatedExprMarker(*this).Visit(E); 9119} 9120 9121/// \brief Emit a diagnostic that describes an effect on the run-time behavior 9122/// of the program being compiled. 9123/// 9124/// This routine emits the given diagnostic when the code currently being 9125/// type-checked is "potentially evaluated", meaning that there is a 9126/// possibility that the code will actually be executable. Code in sizeof() 9127/// expressions, code used only during overload resolution, etc., are not 9128/// potentially evaluated. This routine will suppress such diagnostics or, 9129/// in the absolutely nutty case of potentially potentially evaluated 9130/// expressions (C++ typeid), queue the diagnostic to potentially emit it 9131/// later. 9132/// 9133/// This routine should be used for all diagnostics that describe the run-time 9134/// behavior of a program, such as passing a non-POD value through an ellipsis. 9135/// Failure to do so will likely result in spurious diagnostics or failures 9136/// during overload resolution or within sizeof/alignof/typeof/typeid. 9137bool Sema::DiagRuntimeBehavior(SourceLocation Loc, const Stmt *stmt, 9138 const PartialDiagnostic &PD) { 9139 switch (ExprEvalContexts.back().Context) { 9140 case Unevaluated: 9141 // The argument will never be evaluated, so don't complain. 9142 break; 9143 9144 case PotentiallyEvaluated: 9145 case PotentiallyEvaluatedIfUsed: 9146 if (stmt && getCurFunctionOrMethodDecl()) { 9147 FunctionScopes.back()->PossiblyUnreachableDiags. 9148 push_back(sema::PossiblyUnreachableDiag(PD, Loc, stmt)); 9149 } 9150 else 9151 Diag(Loc, PD); 9152 9153 return true; 9154 9155 case PotentiallyPotentiallyEvaluated: 9156 ExprEvalContexts.back().addDiagnostic(Loc, PD); 9157 break; 9158 } 9159 9160 return false; 9161} 9162 9163bool Sema::CheckCallReturnType(QualType ReturnType, SourceLocation Loc, 9164 CallExpr *CE, FunctionDecl *FD) { 9165 if (ReturnType->isVoidType() || !ReturnType->isIncompleteType()) 9166 return false; 9167 9168 PartialDiagnostic Note = 9169 FD ? PDiag(diag::note_function_with_incomplete_return_type_declared_here) 9170 << FD->getDeclName() : PDiag(); 9171 SourceLocation NoteLoc = FD ? FD->getLocation() : SourceLocation(); 9172 9173 if (RequireCompleteType(Loc, ReturnType, 9174 FD ? 9175 PDiag(diag::err_call_function_incomplete_return) 9176 << CE->getSourceRange() << FD->getDeclName() : 9177 PDiag(diag::err_call_incomplete_return) 9178 << CE->getSourceRange(), 9179 std::make_pair(NoteLoc, Note))) 9180 return true; 9181 9182 return false; 9183} 9184 9185// Diagnose the s/=/==/ and s/\|=/!=/ typos. Note that adding parentheses 9186// will prevent this condition from triggering, which is what we want. 9187void Sema::DiagnoseAssignmentAsCondition(Expr *E) { 9188 SourceLocation Loc; 9189 9190 unsigned diagnostic = diag::warn_condition_is_assignment; 9191 bool IsOrAssign = false; 9192 9193 if (isa<BinaryOperator>(E)) { 9194 BinaryOperator *Op = cast<BinaryOperator>(E); 9195 if (Op->getOpcode() != BO_Assign && Op->getOpcode() != BO_OrAssign) 9196 return; 9197 9198 IsOrAssign = Op->getOpcode() == BO_OrAssign; 9199 9200 // Greylist some idioms by putting them into a warning subcategory. 9201 if (ObjCMessageExpr *ME 9202 = dyn_cast<ObjCMessageExpr>(Op->getRHS()->IgnoreParenCasts())) { 9203 Selector Sel = ME->getSelector(); 9204 9205 // self = [<foo> init...] 9206 if (isSelfExpr(Op->getLHS()) && Sel.getNameForSlot(0).startswith("init")) 9207 diagnostic = diag::warn_condition_is_idiomatic_assignment; 9208 9209 // <foo> = [<bar> nextObject] 9210 else if (Sel.isUnarySelector() && Sel.getNameForSlot(0) == "nextObject") 9211 diagnostic = diag::warn_condition_is_idiomatic_assignment; 9212 } 9213 9214 Loc = Op->getOperatorLoc(); 9215 } else if (isa<CXXOperatorCallExpr>(E)) { 9216 CXXOperatorCallExpr *Op = cast<CXXOperatorCallExpr>(E); 9217 if (Op->getOperator() != OO_Equal && Op->getOperator() != OO_PipeEqual) 9218 return; 9219 9220 IsOrAssign = Op->getOperator() == OO_PipeEqual; 9221 Loc = Op->getOperatorLoc(); 9222 } else { 9223 // Not an assignment. 9224 return; 9225 } 9226 9227 Diag(Loc, diagnostic) << E->getSourceRange(); 9228 9229 SourceLocation Open = E->getSourceRange().getBegin(); 9230 SourceLocation Close = PP.getLocForEndOfToken(E->getSourceRange().getEnd()); 9231 Diag(Loc, diag::note_condition_assign_silence) 9232 << FixItHint::CreateInsertion(Open, "(") 9233 << FixItHint::CreateInsertion(Close, ")"); 9234 9235 if (IsOrAssign) 9236 Diag(Loc, diag::note_condition_or_assign_to_comparison) 9237 << FixItHint::CreateReplacement(Loc, "!="); 9238 else 9239 Diag(Loc, diag::note_condition_assign_to_comparison) 9240 << FixItHint::CreateReplacement(Loc, "=="); 9241} 9242 9243/// \brief Redundant parentheses over an equality comparison can indicate 9244/// that the user intended an assignment used as condition. 9245void Sema::DiagnoseEqualityWithExtraParens(ParenExpr *parenE) { 9246 // Don't warn if the parens came from a macro. 9247 SourceLocation parenLoc = parenE->getLocStart(); 9248 if (parenLoc.isInvalid() || parenLoc.isMacroID()) 9249 return; 9250 // Don't warn for dependent expressions. 9251 if (parenE->isTypeDependent()) 9252 return; 9253 9254 Expr *E = parenE->IgnoreParens(); 9255 9256 if (BinaryOperator *opE = dyn_cast<BinaryOperator>(E)) 9257 if (opE->getOpcode() == BO_EQ && 9258 opE->getLHS()->IgnoreParenImpCasts()->isModifiableLvalue(Context) 9259 == Expr::MLV_Valid) { 9260 SourceLocation Loc = opE->getOperatorLoc(); 9261 9262 Diag(Loc, diag::warn_equality_with_extra_parens) << E->getSourceRange(); 9263 Diag(Loc, diag::note_equality_comparison_silence) 9264 << FixItHint::CreateRemoval(parenE->getSourceRange().getBegin()) 9265 << FixItHint::CreateRemoval(parenE->getSourceRange().getEnd()); 9266 Diag(Loc, diag::note_equality_comparison_to_assign) 9267 << FixItHint::CreateReplacement(Loc, "="); 9268 } 9269} 9270 9271ExprResult Sema::CheckBooleanCondition(Expr *E, SourceLocation Loc) { 9272 DiagnoseAssignmentAsCondition(E); 9273 if (ParenExpr *parenE = dyn_cast<ParenExpr>(E)) 9274 DiagnoseEqualityWithExtraParens(parenE); 9275 9276 ExprResult result = CheckPlaceholderExpr(E); 9277 if (result.isInvalid()) return ExprError(); 9278 E = result.take(); 9279 9280 if (!E->isTypeDependent()) { 9281 if (getLangOptions().CPlusPlus) 9282 return CheckCXXBooleanCondition(E); // C++ 6.4p4 9283 9284 ExprResult ERes = DefaultFunctionArrayLvalueConversion(E); 9285 if (ERes.isInvalid()) 9286 return ExprError(); 9287 E = ERes.take(); 9288 9289 QualType T = E->getType(); 9290 if (!T->isScalarType()) { // C99 6.8.4.1p1 9291 Diag(Loc, diag::err_typecheck_statement_requires_scalar) 9292 << T << E->getSourceRange(); 9293 return ExprError(); 9294 } 9295 } 9296 9297 return Owned(E); 9298} 9299 9300ExprResult Sema::ActOnBooleanCondition(Scope *S, SourceLocation Loc, 9301 Expr *Sub) { 9302 if (!Sub) 9303 return ExprError(); 9304 9305 return CheckBooleanCondition(Sub, Loc); 9306} 9307 9308namespace { 9309 /// A visitor for rebuilding a call to an __unknown_any expression 9310 /// to have an appropriate type. 9311 struct RebuildUnknownAnyFunction 9312 : StmtVisitor<RebuildUnknownAnyFunction, ExprResult> { 9313 9314 Sema &S; 9315 9316 RebuildUnknownAnyFunction(Sema &S) : S(S) {} 9317 9318 ExprResult VisitStmt(Stmt *S) { 9319 llvm_unreachable("unexpected statement!"); 9320 return ExprError(); 9321 } 9322 9323 ExprResult VisitExpr(Expr *expr) { 9324 S.Diag(expr->getExprLoc(), diag::err_unsupported_unknown_any_call) 9325 << expr->getSourceRange(); 9326 return ExprError(); 9327 } 9328 9329 /// Rebuild an expression which simply semantically wraps another 9330 /// expression which it shares the type and value kind of. 9331 template <class T> ExprResult rebuildSugarExpr(T *expr) { 9332 ExprResult subResult = Visit(expr->getSubExpr()); 9333 if (subResult.isInvalid()) return ExprError(); 9334 9335 Expr *subExpr = subResult.take(); 9336 expr->setSubExpr(subExpr); 9337 expr->setType(subExpr->getType()); 9338 expr->setValueKind(subExpr->getValueKind()); 9339 assert(expr->getObjectKind() == OK_Ordinary); 9340 return expr; 9341 } 9342 9343 ExprResult VisitParenExpr(ParenExpr *paren) { 9344 return rebuildSugarExpr(paren); 9345 } 9346 9347 ExprResult VisitUnaryExtension(UnaryOperator *op) { 9348 return rebuildSugarExpr(op); 9349 } 9350 9351 ExprResult VisitUnaryAddrOf(UnaryOperator *op) { 9352 ExprResult subResult = Visit(op->getSubExpr()); 9353 if (subResult.isInvalid()) return ExprError(); 9354 9355 Expr *subExpr = subResult.take(); 9356 op->setSubExpr(subExpr); 9357 op->setType(S.Context.getPointerType(subExpr->getType())); 9358 assert(op->getValueKind() == VK_RValue); 9359 assert(op->getObjectKind() == OK_Ordinary); 9360 return op; 9361 } 9362 9363 ExprResult resolveDecl(Expr *expr, ValueDecl *decl) { 9364 if (!isa<FunctionDecl>(decl)) return VisitExpr(expr); 9365 9366 expr->setType(decl->getType()); 9367 9368 assert(expr->getValueKind() == VK_RValue); 9369 if (S.getLangOptions().CPlusPlus && 9370 !(isa<CXXMethodDecl>(decl) && 9371 cast<CXXMethodDecl>(decl)->isInstance())) 9372 expr->setValueKind(VK_LValue); 9373 9374 return expr; 9375 } 9376 9377 ExprResult VisitMemberExpr(MemberExpr *mem) { 9378 return resolveDecl(mem, mem->getMemberDecl()); 9379 } 9380 9381 ExprResult VisitDeclRefExpr(DeclRefExpr *ref) { 9382 return resolveDecl(ref, ref->getDecl()); 9383 } 9384 }; 9385} 9386 9387/// Given a function expression of unknown-any type, try to rebuild it 9388/// to have a function type. 9389static ExprResult rebuildUnknownAnyFunction(Sema &S, Expr *fn) { 9390 ExprResult result = RebuildUnknownAnyFunction(S).Visit(fn); 9391 if (result.isInvalid()) return ExprError(); 9392 return S.DefaultFunctionArrayConversion(result.take()); 9393} 9394 9395namespace { 9396 /// A visitor for rebuilding an expression of type __unknown_anytype 9397 /// into one which resolves the type directly on the referring 9398 /// expression. Strict preservation of the original source 9399 /// structure is not a goal. 9400 struct RebuildUnknownAnyExpr 9401 : StmtVisitor<RebuildUnknownAnyExpr, ExprResult> { 9402 9403 Sema &S; 9404 9405 /// The current destination type. 9406 QualType DestType; 9407 9408 RebuildUnknownAnyExpr(Sema &S, QualType castType) 9409 : S(S), DestType(castType) {} 9410 9411 ExprResult VisitStmt(Stmt *S) { 9412 llvm_unreachable("unexpected statement!"); 9413 return ExprError(); 9414 } 9415 9416 ExprResult VisitExpr(Expr *expr) { 9417 S.Diag(expr->getExprLoc(), diag::err_unsupported_unknown_any_expr) 9418 << expr->getSourceRange(); 9419 return ExprError(); 9420 } 9421 9422 ExprResult VisitCallExpr(CallExpr *call); 9423 ExprResult VisitObjCMessageExpr(ObjCMessageExpr *message); 9424 9425 /// Rebuild an expression which simply semantically wraps another 9426 /// expression which it shares the type and value kind of. 9427 template <class T> ExprResult rebuildSugarExpr(T *expr) { 9428 ExprResult subResult = Visit(expr->getSubExpr()); 9429 if (subResult.isInvalid()) return ExprError(); 9430 Expr *subExpr = subResult.take(); 9431 expr->setSubExpr(subExpr); 9432 expr->setType(subExpr->getType()); 9433 expr->setValueKind(subExpr->getValueKind()); 9434 assert(expr->getObjectKind() == OK_Ordinary); 9435 return expr; 9436 } 9437 9438 ExprResult VisitParenExpr(ParenExpr *paren) { 9439 return rebuildSugarExpr(paren); 9440 } 9441 9442 ExprResult VisitUnaryExtension(UnaryOperator *op) { 9443 return rebuildSugarExpr(op); 9444 } 9445 9446 ExprResult VisitUnaryAddrOf(UnaryOperator *op) { 9447 const PointerType *ptr = DestType->getAs<PointerType>(); 9448 if (!ptr) { 9449 S.Diag(op->getOperatorLoc(), diag::err_unknown_any_addrof) 9450 << op->getSourceRange(); 9451 return ExprError(); 9452 } 9453 assert(op->getValueKind() == VK_RValue); 9454 assert(op->getObjectKind() == OK_Ordinary); 9455 op->setType(DestType); 9456 9457 // Build the sub-expression as if it were an object of the pointee type. 9458 DestType = ptr->getPointeeType(); 9459 ExprResult subResult = Visit(op->getSubExpr()); 9460 if (subResult.isInvalid()) return ExprError(); 9461 op->setSubExpr(subResult.take()); 9462 return op; 9463 } 9464 9465 ExprResult VisitImplicitCastExpr(ImplicitCastExpr *ice); 9466 9467 ExprResult resolveDecl(Expr *expr, ValueDecl *decl); 9468 9469 ExprResult VisitMemberExpr(MemberExpr *mem) { 9470 return resolveDecl(mem, mem->getMemberDecl()); 9471 } 9472 9473 ExprResult VisitDeclRefExpr(DeclRefExpr *ref) { 9474 return resolveDecl(ref, ref->getDecl()); 9475 } 9476 }; 9477} 9478 9479/// Rebuilds a call expression which yielded __unknown_anytype. 9480ExprResult RebuildUnknownAnyExpr::VisitCallExpr(CallExpr *call) { 9481 Expr *callee = call->getCallee(); 9482 9483 enum FnKind { 9484 FK_MemberFunction, 9485 FK_FunctionPointer, 9486 FK_BlockPointer 9487 }; 9488 9489 FnKind kind; 9490 QualType type = callee->getType(); 9491 if (type == S.Context.BoundMemberTy) { 9492 assert(isa<CXXMemberCallExpr>(call) || isa<CXXOperatorCallExpr>(call)); 9493 kind = FK_MemberFunction; 9494 type = Expr::findBoundMemberType(callee); 9495 } else if (const PointerType *ptr = type->getAs<PointerType>()) { 9496 type = ptr->getPointeeType(); 9497 kind = FK_FunctionPointer; 9498 } else { 9499 type = type->castAs<BlockPointerType>()->getPointeeType(); 9500 kind = FK_BlockPointer; 9501 } 9502 const FunctionType *fnType = type->castAs<FunctionType>(); 9503 9504 // Verify that this is a legal result type of a function. 9505 if (DestType->isArrayType() || DestType->isFunctionType()) { 9506 unsigned diagID = diag::err_func_returning_array_function; 9507 if (kind == FK_BlockPointer) 9508 diagID = diag::err_block_returning_array_function; 9509 9510 S.Diag(call->getExprLoc(), diagID) 9511 << DestType->isFunctionType() << DestType; 9512 return ExprError(); 9513 } 9514 9515 // Otherwise, go ahead and set DestType as the call's result. 9516 call->setType(DestType.getNonLValueExprType(S.Context)); 9517 call->setValueKind(Expr::getValueKindForType(DestType)); 9518 assert(call->getObjectKind() == OK_Ordinary); 9519 9520 // Rebuild the function type, replacing the result type with DestType. 9521 if (const FunctionProtoType *proto = dyn_cast<FunctionProtoType>(fnType)) 9522 DestType = S.Context.getFunctionType(DestType, 9523 proto->arg_type_begin(), 9524 proto->getNumArgs(), 9525 proto->getExtProtoInfo()); 9526 else 9527 DestType = S.Context.getFunctionNoProtoType(DestType, 9528 fnType->getExtInfo()); 9529 9530 // Rebuild the appropriate pointer-to-function type. 9531 switch (kind) { 9532 case FK_MemberFunction: 9533 // Nothing to do. 9534 break; 9535 9536 case FK_FunctionPointer: 9537 DestType = S.Context.getPointerType(DestType); 9538 break; 9539 9540 case FK_BlockPointer: 9541 DestType = S.Context.getBlockPointerType(DestType); 9542 break; 9543 } 9544 9545 // Finally, we can recurse. 9546 ExprResult calleeResult = Visit(callee); 9547 if (!calleeResult.isUsable()) return ExprError(); 9548 call->setCallee(calleeResult.take()); 9549 9550 // Bind a temporary if necessary. 9551 return S.MaybeBindToTemporary(call); 9552} 9553 9554ExprResult RebuildUnknownAnyExpr::VisitObjCMessageExpr(ObjCMessageExpr *msg) { 9555 // Verify that this is a legal result type of a call. 9556 if (DestType->isArrayType() || DestType->isFunctionType()) { 9557 S.Diag(msg->getExprLoc(), diag::err_func_returning_array_function) 9558 << DestType->isFunctionType() << DestType; 9559 return ExprError(); 9560 } 9561 9562 // Rewrite the method result type if available. 9563 if (ObjCMethodDecl *method = msg->getMethodDecl()) { 9564 assert(method->getResultType() == S.Context.UnknownAnyTy); 9565 method->setResultType(DestType); 9566 } 9567 9568 // Change the type of the message. 9569 msg->setType(DestType.getNonReferenceType()); 9570 msg->setValueKind(Expr::getValueKindForType(DestType)); 9571 9572 return S.MaybeBindToTemporary(msg); 9573} 9574 9575ExprResult RebuildUnknownAnyExpr::VisitImplicitCastExpr(ImplicitCastExpr *ice) { 9576 // The only case we should ever see here is a function-to-pointer decay. 9577 assert(ice->getCastKind() == CK_FunctionToPointerDecay); 9578 assert(ice->getValueKind() == VK_RValue); 9579 assert(ice->getObjectKind() == OK_Ordinary); 9580 9581 ice->setType(DestType); 9582 9583 // Rebuild the sub-expression as the pointee (function) type. 9584 DestType = DestType->castAs<PointerType>()->getPointeeType(); 9585 9586 ExprResult result = Visit(ice->getSubExpr()); 9587 if (!result.isUsable()) return ExprError(); 9588 9589 ice->setSubExpr(result.take()); 9590 return S.Owned(ice); 9591} 9592 9593ExprResult RebuildUnknownAnyExpr::resolveDecl(Expr *expr, ValueDecl *decl) { 9594 ExprValueKind valueKind = VK_LValue; 9595 QualType type = DestType; 9596 9597 // We know how to make this work for certain kinds of decls: 9598 9599 // - functions 9600 if (FunctionDecl *fn = dyn_cast<FunctionDecl>(decl)) { 9601 // This is true because FunctionDecls must always have function 9602 // type, so we can't be resolving the entire thing at once. 9603 assert(type->isFunctionType()); 9604 9605 if (CXXMethodDecl *method = dyn_cast<CXXMethodDecl>(fn)) 9606 if (method->isInstance()) { 9607 valueKind = VK_RValue; 9608 type = S.Context.BoundMemberTy; 9609 } 9610 9611 // Function references aren't l-values in C. 9612 if (!S.getLangOptions().CPlusPlus) 9613 valueKind = VK_RValue; 9614 9615 // - variables 9616 } else if (isa<VarDecl>(decl)) { 9617 if (const ReferenceType *refTy = type->getAs<ReferenceType>()) { 9618 type = refTy->getPointeeType(); 9619 } else if (type->isFunctionType()) { 9620 S.Diag(expr->getExprLoc(), diag::err_unknown_any_var_function_type) 9621 << decl << expr->getSourceRange(); 9622 return ExprError(); 9623 } 9624 9625 // - nothing else 9626 } else { 9627 S.Diag(expr->getExprLoc(), diag::err_unsupported_unknown_any_decl) 9628 << decl << expr->getSourceRange(); 9629 return ExprError(); 9630 } 9631 9632 decl->setType(DestType); 9633 expr->setType(type); 9634 expr->setValueKind(valueKind); 9635 return S.Owned(expr); 9636} 9637 9638/// Check a cast of an unknown-any type. We intentionally only 9639/// trigger this for C-style casts. 9640ExprResult Sema::checkUnknownAnyCast(SourceRange typeRange, QualType castType, 9641 Expr *castExpr, CastKind &castKind, 9642 ExprValueKind &VK, CXXCastPath &path) { 9643 // Rewrite the casted expression from scratch. 9644 ExprResult result = RebuildUnknownAnyExpr(*this, castType).Visit(castExpr); 9645 if (!result.isUsable()) return ExprError(); 9646 9647 castExpr = result.take(); 9648 VK = castExpr->getValueKind(); 9649 castKind = CK_NoOp; 9650 9651 return castExpr; 9652} 9653 9654static ExprResult diagnoseUnknownAnyExpr(Sema &S, Expr *e) { 9655 Expr *orig = e; 9656 unsigned diagID = diag::err_uncasted_use_of_unknown_any; 9657 while (true) { 9658 e = e->IgnoreParenImpCasts(); 9659 if (CallExpr *call = dyn_cast<CallExpr>(e)) { 9660 e = call->getCallee(); 9661 diagID = diag::err_uncasted_call_of_unknown_any; 9662 } else { 9663 break; 9664 } 9665 } 9666 9667 SourceLocation loc; 9668 NamedDecl *d; 9669 if (DeclRefExpr *ref = dyn_cast<DeclRefExpr>(e)) { 9670 loc = ref->getLocation(); 9671 d = ref->getDecl(); 9672 } else if (MemberExpr *mem = dyn_cast<MemberExpr>(e)) { 9673 loc = mem->getMemberLoc(); 9674 d = mem->getMemberDecl(); 9675 } else if (ObjCMessageExpr *msg = dyn_cast<ObjCMessageExpr>(e)) { 9676 diagID = diag::err_uncasted_call_of_unknown_any; 9677 loc = msg->getSelectorLoc(); 9678 d = msg->getMethodDecl(); 9679 assert(d && "unknown method returning __unknown_any?"); 9680 } else { 9681 S.Diag(e->getExprLoc(), diag::err_unsupported_unknown_any_expr) 9682 << e->getSourceRange(); 9683 return ExprError(); 9684 } 9685 9686 S.Diag(loc, diagID) << d << orig->getSourceRange(); 9687 9688 // Never recoverable. 9689 return ExprError(); 9690} 9691 9692/// Check for operands with placeholder types and complain if found. 9693/// Returns true if there was an error and no recovery was possible. 9694ExprResult Sema::CheckPlaceholderExpr(Expr *E) { 9695 // Placeholder types are always *exactly* the appropriate builtin type. 9696 QualType type = E->getType(); 9697 9698 // Overloaded expressions. 9699 if (type == Context.OverloadTy) 9700 return ResolveAndFixSingleFunctionTemplateSpecialization(E, false, true, 9701 E->getSourceRange(), 9702 QualType(), 9703 diag::err_ovl_unresolvable); 9704 9705 // Bound member functions. 9706 if (type == Context.BoundMemberTy) { 9707 Diag(E->getLocStart(), diag::err_invalid_use_of_bound_member_func) 9708 << E->getSourceRange(); 9709 return ExprError(); 9710 } 9711 9712 // Expressions of unknown type. 9713 if (type == Context.UnknownAnyTy) 9714 return diagnoseUnknownAnyExpr(*this, E); 9715 9716 assert(!type->isPlaceholderType()); 9717 return Owned(E); 9718} 9719 9720bool Sema::CheckCaseExpression(Expr *expr) { 9721 if (expr->isTypeDependent()) 9722 return true; 9723 if (expr->isValueDependent() || expr->isIntegerConstantExpr(Context)) 9724 return expr->getType()->isIntegralOrEnumerationType(); 9725 return false; 9726} 9727