SemaExpr.cpp revision 89ebaed91cca7fd296ec7804e4e9fb68949c1d0e
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/CXXInheritance.h" 20#include "clang/AST/DeclObjC.h" 21#include "clang/AST/DeclTemplate.h" 22#include "clang/AST/EvaluatedExprVisitor.h" 23#include "clang/AST/Expr.h" 24#include "clang/AST/ExprCXX.h" 25#include "clang/AST/ExprObjC.h" 26#include "clang/AST/RecursiveASTVisitor.h" 27#include "clang/AST/TypeLoc.h" 28#include "clang/Basic/PartialDiagnostic.h" 29#include "clang/Basic/SourceManager.h" 30#include "clang/Basic/TargetInfo.h" 31#include "clang/Lex/LiteralSupport.h" 32#include "clang/Lex/Preprocessor.h" 33#include "clang/Sema/DeclSpec.h" 34#include "clang/Sema/Designator.h" 35#include "clang/Sema/Scope.h" 36#include "clang/Sema/ScopeInfo.h" 37#include "clang/Sema/ParsedTemplate.h" 38#include "clang/Sema/Template.h" 39using namespace clang; 40using namespace sema; 41 42 43/// \brief Determine whether the use of this declaration is valid, and 44/// emit any corresponding diagnostics. 45/// 46/// This routine diagnoses various problems with referencing 47/// declarations that can occur when using a declaration. For example, 48/// it might warn if a deprecated or unavailable declaration is being 49/// used, or produce an error (and return true) if a C++0x deleted 50/// function is being used. 51/// 52/// If IgnoreDeprecated is set to true, this should not warn about deprecated 53/// decls. 54/// 55/// \returns true if there was an error (this declaration cannot be 56/// referenced), false otherwise. 57/// 58bool Sema::DiagnoseUseOfDecl(NamedDecl *D, SourceLocation Loc, 59 const ObjCInterfaceDecl *UnknownObjCClass) { 60 if (getLangOptions().CPlusPlus && isa<FunctionDecl>(D)) { 61 // If there were any diagnostics suppressed by template argument deduction, 62 // emit them now. 63 llvm::DenseMap<Decl *, llvm::SmallVector<PartialDiagnosticAt, 1> >::iterator 64 Pos = SuppressedDiagnostics.find(D->getCanonicalDecl()); 65 if (Pos != SuppressedDiagnostics.end()) { 66 llvm::SmallVectorImpl<PartialDiagnosticAt> &Suppressed = Pos->second; 67 for (unsigned I = 0, N = Suppressed.size(); I != N; ++I) 68 Diag(Suppressed[I].first, Suppressed[I].second); 69 70 // Clear out the list of suppressed diagnostics, so that we don't emit 71 // them again for this specialization. However, we don't obsolete this 72 // entry from the table, because we want to avoid ever emitting these 73 // diagnostics again. 74 Suppressed.clear(); 75 } 76 } 77 78 // See if this is an auto-typed variable whose initializer we are parsing. 79 if (ParsingInitForAutoVars.count(D)) { 80 Diag(Loc, diag::err_auto_variable_cannot_appear_in_own_initializer) 81 << D->getDeclName(); 82 return true; 83 } 84 85 // See if this is a deleted function. 86 if (FunctionDecl *FD = dyn_cast<FunctionDecl>(D)) { 87 if (FD->isDeleted()) { 88 Diag(Loc, diag::err_deleted_function_use); 89 Diag(D->getLocation(), diag::note_unavailable_here) << true; 90 return true; 91 } 92 } 93 94 // See if this declaration is unavailable or deprecated. 95 std::string Message; 96 switch (D->getAvailability(&Message)) { 97 case AR_Available: 98 case AR_NotYetIntroduced: 99 break; 100 101 case AR_Deprecated: 102 EmitDeprecationWarning(D, Message, Loc, UnknownObjCClass); 103 break; 104 105 case AR_Unavailable: 106 if (Message.empty()) { 107 if (!UnknownObjCClass) 108 Diag(Loc, diag::err_unavailable) << D->getDeclName(); 109 else 110 Diag(Loc, diag::warn_unavailable_fwdclass_message) 111 << D->getDeclName(); 112 } 113 else 114 Diag(Loc, diag::err_unavailable_message) 115 << D->getDeclName() << Message; 116 Diag(D->getLocation(), diag::note_unavailable_here) << 0; 117 break; 118 } 119 120 // Warn if this is used but marked unused. 121 if (D->hasAttr<UnusedAttr>()) 122 Diag(Loc, diag::warn_used_but_marked_unused) << D->getDeclName(); 123 124 return false; 125} 126 127/// \brief Retrieve the message suffix that should be added to a 128/// diagnostic complaining about the given function being deleted or 129/// unavailable. 130std::string Sema::getDeletedOrUnavailableSuffix(const FunctionDecl *FD) { 131 // FIXME: C++0x implicitly-deleted special member functions could be 132 // detected here so that we could improve diagnostics to say, e.g., 133 // "base class 'A' had a deleted copy constructor". 134 if (FD->isDeleted()) 135 return std::string(); 136 137 std::string Message; 138 if (FD->getAvailability(&Message)) 139 return ": " + Message; 140 141 return std::string(); 142} 143 144/// DiagnoseSentinelCalls - This routine checks on method dispatch calls 145/// (and other functions in future), which have been declared with sentinel 146/// attribute. It warns if call does not have the sentinel argument. 147/// 148void Sema::DiagnoseSentinelCalls(NamedDecl *D, SourceLocation Loc, 149 Expr **Args, unsigned NumArgs) { 150 const SentinelAttr *attr = D->getAttr<SentinelAttr>(); 151 if (!attr) 152 return; 153 154 // FIXME: In C++0x, if any of the arguments are parameter pack 155 // expansions, we can't check for the sentinel now. 156 int sentinelPos = attr->getSentinel(); 157 int nullPos = attr->getNullPos(); 158 159 // FIXME. ObjCMethodDecl and FunctionDecl need be derived from the same common 160 // base class. Then we won't be needing two versions of the same code. 161 unsigned int i = 0; 162 bool warnNotEnoughArgs = false; 163 int isMethod = 0; 164 if (ObjCMethodDecl *MD = dyn_cast<ObjCMethodDecl>(D)) { 165 // skip over named parameters. 166 ObjCMethodDecl::param_iterator P, E = MD->param_end(); 167 for (P = MD->param_begin(); (P != E && i < NumArgs); ++P) { 168 if (nullPos) 169 --nullPos; 170 else 171 ++i; 172 } 173 warnNotEnoughArgs = (P != E || i >= NumArgs); 174 isMethod = 1; 175 } else if (FunctionDecl *FD = dyn_cast<FunctionDecl>(D)) { 176 // skip over named parameters. 177 ObjCMethodDecl::param_iterator P, E = FD->param_end(); 178 for (P = FD->param_begin(); (P != E && i < NumArgs); ++P) { 179 if (nullPos) 180 --nullPos; 181 else 182 ++i; 183 } 184 warnNotEnoughArgs = (P != E || i >= NumArgs); 185 } else if (VarDecl *V = dyn_cast<VarDecl>(D)) { 186 // block or function pointer call. 187 QualType Ty = V->getType(); 188 if (Ty->isBlockPointerType() || Ty->isFunctionPointerType()) { 189 const FunctionType *FT = Ty->isFunctionPointerType() 190 ? Ty->getAs<PointerType>()->getPointeeType()->getAs<FunctionType>() 191 : Ty->getAs<BlockPointerType>()->getPointeeType()->getAs<FunctionType>(); 192 if (const FunctionProtoType *Proto = dyn_cast<FunctionProtoType>(FT)) { 193 unsigned NumArgsInProto = Proto->getNumArgs(); 194 unsigned k; 195 for (k = 0; (k != NumArgsInProto && i < NumArgs); k++) { 196 if (nullPos) 197 --nullPos; 198 else 199 ++i; 200 } 201 warnNotEnoughArgs = (k != NumArgsInProto || i >= NumArgs); 202 } 203 if (Ty->isBlockPointerType()) 204 isMethod = 2; 205 } else 206 return; 207 } else 208 return; 209 210 if (warnNotEnoughArgs) { 211 Diag(Loc, diag::warn_not_enough_argument) << D->getDeclName(); 212 Diag(D->getLocation(), diag::note_sentinel_here) << isMethod; 213 return; 214 } 215 int sentinel = i; 216 while (sentinelPos > 0 && i < NumArgs-1) { 217 --sentinelPos; 218 ++i; 219 } 220 if (sentinelPos > 0) { 221 Diag(Loc, diag::warn_not_enough_argument) << D->getDeclName(); 222 Diag(D->getLocation(), diag::note_sentinel_here) << isMethod; 223 return; 224 } 225 while (i < NumArgs-1) { 226 ++i; 227 ++sentinel; 228 } 229 Expr *sentinelExpr = Args[sentinel]; 230 if (!sentinelExpr) return; 231 if (sentinelExpr->isTypeDependent()) return; 232 if (sentinelExpr->isValueDependent()) return; 233 234 // nullptr_t is always treated as null. 235 if (sentinelExpr->getType()->isNullPtrType()) return; 236 237 if (sentinelExpr->getType()->isAnyPointerType() && 238 sentinelExpr->IgnoreParenCasts()->isNullPointerConstant(Context, 239 Expr::NPC_ValueDependentIsNull)) 240 return; 241 242 // Unfortunately, __null has type 'int'. 243 if (isa<GNUNullExpr>(sentinelExpr)) return; 244 245 Diag(Loc, diag::warn_missing_sentinel) << isMethod; 246 Diag(D->getLocation(), diag::note_sentinel_here) << isMethod; 247} 248 249SourceRange Sema::getExprRange(ExprTy *E) const { 250 Expr *Ex = (Expr *)E; 251 return Ex? Ex->getSourceRange() : SourceRange(); 252} 253 254//===----------------------------------------------------------------------===// 255// Standard Promotions and Conversions 256//===----------------------------------------------------------------------===// 257 258/// DefaultFunctionArrayConversion (C99 6.3.2.1p3, C99 6.3.2.1p4). 259ExprResult Sema::DefaultFunctionArrayConversion(Expr *E) { 260 QualType Ty = E->getType(); 261 assert(!Ty.isNull() && "DefaultFunctionArrayConversion - missing type"); 262 263 if (Ty->isFunctionType()) 264 E = ImpCastExprToType(E, Context.getPointerType(Ty), 265 CK_FunctionToPointerDecay).take(); 266 else if (Ty->isArrayType()) { 267 // In C90 mode, arrays only promote to pointers if the array expression is 268 // an lvalue. The relevant legalese is C90 6.2.2.1p3: "an lvalue that has 269 // type 'array of type' is converted to an expression that has type 'pointer 270 // to type'...". In C99 this was changed to: C99 6.3.2.1p3: "an expression 271 // that has type 'array of type' ...". The relevant change is "an lvalue" 272 // (C90) to "an expression" (C99). 273 // 274 // C++ 4.2p1: 275 // An lvalue or rvalue of type "array of N T" or "array of unknown bound of 276 // T" can be converted to an rvalue of type "pointer to T". 277 // 278 if (getLangOptions().C99 || getLangOptions().CPlusPlus || E->isLValue()) 279 E = ImpCastExprToType(E, Context.getArrayDecayedType(Ty), 280 CK_ArrayToPointerDecay).take(); 281 } 282 return Owned(E); 283} 284 285ExprResult Sema::DefaultLvalueConversion(Expr *E) { 286 // C++ [conv.lval]p1: 287 // A glvalue of a non-function, non-array type T can be 288 // converted to a prvalue. 289 if (!E->isGLValue()) return Owned(E); 290 291 QualType T = E->getType(); 292 assert(!T.isNull() && "r-value conversion on typeless expression?"); 293 294 // Create a load out of an ObjCProperty l-value, if necessary. 295 if (E->getObjectKind() == OK_ObjCProperty) { 296 ExprResult Res = ConvertPropertyForRValue(E); 297 if (Res.isInvalid()) 298 return Owned(E); 299 E = Res.take(); 300 if (!E->isGLValue()) 301 return Owned(E); 302 } 303 304 // We don't want to throw lvalue-to-rvalue casts on top of 305 // expressions of certain types in C++. 306 if (getLangOptions().CPlusPlus && 307 (E->getType() == Context.OverloadTy || 308 T->isDependentType() || 309 T->isRecordType())) 310 return Owned(E); 311 312 // The C standard is actually really unclear on this point, and 313 // DR106 tells us what the result should be but not why. It's 314 // generally best to say that void types just doesn't undergo 315 // lvalue-to-rvalue at all. Note that expressions of unqualified 316 // 'void' type are never l-values, but qualified void can be. 317 if (T->isVoidType()) 318 return Owned(E); 319 320 // C++ [conv.lval]p1: 321 // [...] If T is a non-class type, the type of the prvalue is the 322 // cv-unqualified version of T. Otherwise, the type of the 323 // rvalue is T. 324 // 325 // C99 6.3.2.1p2: 326 // If the lvalue has qualified type, the value has the unqualified 327 // version of the type of the lvalue; otherwise, the value has the 328 // type of the lvalue. 329 if (T.hasQualifiers()) 330 T = T.getUnqualifiedType(); 331 332 CheckArrayAccess(E); 333 334 return Owned(ImplicitCastExpr::Create(Context, T, CK_LValueToRValue, 335 E, 0, VK_RValue)); 336} 337 338ExprResult Sema::DefaultFunctionArrayLvalueConversion(Expr *E) { 339 ExprResult Res = DefaultFunctionArrayConversion(E); 340 if (Res.isInvalid()) 341 return ExprError(); 342 Res = DefaultLvalueConversion(Res.take()); 343 if (Res.isInvalid()) 344 return ExprError(); 345 return move(Res); 346} 347 348 349/// UsualUnaryConversions - Performs various conversions that are common to most 350/// operators (C99 6.3). The conversions of array and function types are 351/// sometimes suppressed. For example, the array->pointer conversion doesn't 352/// apply if the array is an argument to the sizeof or address (&) operators. 353/// In these instances, this routine should *not* be called. 354ExprResult Sema::UsualUnaryConversions(Expr *E) { 355 // First, convert to an r-value. 356 ExprResult Res = DefaultFunctionArrayLvalueConversion(E); 357 if (Res.isInvalid()) 358 return Owned(E); 359 E = Res.take(); 360 361 QualType Ty = E->getType(); 362 assert(!Ty.isNull() && "UsualUnaryConversions - missing type"); 363 364 // Try to perform integral promotions if the object has a theoretically 365 // promotable type. 366 if (Ty->isIntegralOrUnscopedEnumerationType()) { 367 // C99 6.3.1.1p2: 368 // 369 // The following may be used in an expression wherever an int or 370 // unsigned int may be used: 371 // - an object or expression with an integer type whose integer 372 // conversion rank is less than or equal to the rank of int 373 // and unsigned int. 374 // - A bit-field of type _Bool, int, signed int, or unsigned int. 375 // 376 // If an int can represent all values of the original type, the 377 // value is converted to an int; otherwise, it is converted to an 378 // unsigned int. These are called the integer promotions. All 379 // other types are unchanged by the integer promotions. 380 381 QualType PTy = Context.isPromotableBitField(E); 382 if (!PTy.isNull()) { 383 E = ImpCastExprToType(E, PTy, CK_IntegralCast).take(); 384 return Owned(E); 385 } 386 if (Ty->isPromotableIntegerType()) { 387 QualType PT = Context.getPromotedIntegerType(Ty); 388 E = ImpCastExprToType(E, PT, CK_IntegralCast).take(); 389 return Owned(E); 390 } 391 } 392 return Owned(E); 393} 394 395/// DefaultArgumentPromotion (C99 6.5.2.2p6). Used for function calls that 396/// do not have a prototype. Arguments that have type float are promoted to 397/// double. All other argument types are converted by UsualUnaryConversions(). 398ExprResult Sema::DefaultArgumentPromotion(Expr *E) { 399 QualType Ty = E->getType(); 400 assert(!Ty.isNull() && "DefaultArgumentPromotion - missing type"); 401 402 ExprResult Res = UsualUnaryConversions(E); 403 if (Res.isInvalid()) 404 return Owned(E); 405 E = Res.take(); 406 407 // If this is a 'float' (CVR qualified or typedef) promote to double. 408 if (Ty->isSpecificBuiltinType(BuiltinType::Float)) 409 E = ImpCastExprToType(E, Context.DoubleTy, CK_FloatingCast).take(); 410 411 return Owned(E); 412} 413 414/// DefaultVariadicArgumentPromotion - Like DefaultArgumentPromotion, but 415/// will warn if the resulting type is not a POD type, and rejects ObjC 416/// interfaces passed by value. 417ExprResult Sema::DefaultVariadicArgumentPromotion(Expr *E, VariadicCallType CT, 418 FunctionDecl *FDecl) { 419 ExprResult ExprRes = DefaultArgumentPromotion(E); 420 if (ExprRes.isInvalid()) 421 return ExprError(); 422 E = ExprRes.take(); 423 424 // __builtin_va_start takes the second argument as a "varargs" argument, but 425 // it doesn't actually do anything with it. It doesn't need to be non-pod 426 // etc. 427 if (FDecl && FDecl->getBuiltinID() == Builtin::BI__builtin_va_start) 428 return Owned(E); 429 430 if (E->getType()->isObjCObjectType() && 431 DiagRuntimeBehavior(E->getLocStart(), 0, 432 PDiag(diag::err_cannot_pass_objc_interface_to_vararg) 433 << E->getType() << CT)) 434 return ExprError(); 435 436 if (!E->getType()->isPODType() && 437 DiagRuntimeBehavior(E->getLocStart(), 0, 438 PDiag(diag::warn_cannot_pass_non_pod_arg_to_vararg) 439 << E->getType() << CT)) 440 return ExprError(); 441 442 return Owned(E); 443} 444 445/// UsualArithmeticConversions - Performs various conversions that are common to 446/// binary operators (C99 6.3.1.8). If both operands aren't arithmetic, this 447/// routine returns the first non-arithmetic type found. The client is 448/// responsible for emitting appropriate error diagnostics. 449/// FIXME: verify the conversion rules for "complex int" are consistent with 450/// GCC. 451QualType Sema::UsualArithmeticConversions(ExprResult &lhsExpr, ExprResult &rhsExpr, 452 bool isCompAssign) { 453 if (!isCompAssign) { 454 lhsExpr = UsualUnaryConversions(lhsExpr.take()); 455 if (lhsExpr.isInvalid()) 456 return QualType(); 457 } 458 459 rhsExpr = UsualUnaryConversions(rhsExpr.take()); 460 if (rhsExpr.isInvalid()) 461 return QualType(); 462 463 // For conversion purposes, we ignore any qualifiers. 464 // For example, "const float" and "float" are equivalent. 465 QualType lhs = 466 Context.getCanonicalType(lhsExpr.get()->getType()).getUnqualifiedType(); 467 QualType rhs = 468 Context.getCanonicalType(rhsExpr.get()->getType()).getUnqualifiedType(); 469 470 // If both types are identical, no conversion is needed. 471 if (lhs == rhs) 472 return lhs; 473 474 // If either side is a non-arithmetic type (e.g. a pointer), we are done. 475 // The caller can deal with this (e.g. pointer + int). 476 if (!lhs->isArithmeticType() || !rhs->isArithmeticType()) 477 return lhs; 478 479 // Apply unary and bitfield promotions to the LHS's type. 480 QualType lhs_unpromoted = lhs; 481 if (lhs->isPromotableIntegerType()) 482 lhs = Context.getPromotedIntegerType(lhs); 483 QualType LHSBitfieldPromoteTy = Context.isPromotableBitField(lhsExpr.get()); 484 if (!LHSBitfieldPromoteTy.isNull()) 485 lhs = LHSBitfieldPromoteTy; 486 if (lhs != lhs_unpromoted && !isCompAssign) 487 lhsExpr = ImpCastExprToType(lhsExpr.take(), lhs, CK_IntegralCast); 488 489 // If both types are identical, no conversion is needed. 490 if (lhs == rhs) 491 return lhs; 492 493 // At this point, we have two different arithmetic types. 494 495 // Handle complex types first (C99 6.3.1.8p1). 496 bool LHSComplexFloat = lhs->isComplexType(); 497 bool RHSComplexFloat = rhs->isComplexType(); 498 if (LHSComplexFloat || RHSComplexFloat) { 499 // if we have an integer operand, the result is the complex type. 500 501 if (!RHSComplexFloat && !rhs->isRealFloatingType()) { 502 if (rhs->isIntegerType()) { 503 QualType fp = cast<ComplexType>(lhs)->getElementType(); 504 rhsExpr = ImpCastExprToType(rhsExpr.take(), fp, CK_IntegralToFloating); 505 rhsExpr = ImpCastExprToType(rhsExpr.take(), lhs, CK_FloatingRealToComplex); 506 } else { 507 assert(rhs->isComplexIntegerType()); 508 rhsExpr = ImpCastExprToType(rhsExpr.take(), lhs, CK_IntegralComplexToFloatingComplex); 509 } 510 return lhs; 511 } 512 513 if (!LHSComplexFloat && !lhs->isRealFloatingType()) { 514 if (!isCompAssign) { 515 // int -> float -> _Complex float 516 if (lhs->isIntegerType()) { 517 QualType fp = cast<ComplexType>(rhs)->getElementType(); 518 lhsExpr = ImpCastExprToType(lhsExpr.take(), fp, CK_IntegralToFloating); 519 lhsExpr = ImpCastExprToType(lhsExpr.take(), rhs, CK_FloatingRealToComplex); 520 } else { 521 assert(lhs->isComplexIntegerType()); 522 lhsExpr = ImpCastExprToType(lhsExpr.take(), rhs, CK_IntegralComplexToFloatingComplex); 523 } 524 } 525 return rhs; 526 } 527 528 // This handles complex/complex, complex/float, or float/complex. 529 // When both operands are complex, the shorter operand is converted to the 530 // type of the longer, and that is the type of the result. This corresponds 531 // to what is done when combining two real floating-point operands. 532 // The fun begins when size promotion occur across type domains. 533 // From H&S 6.3.4: When one operand is complex and the other is a real 534 // floating-point type, the less precise type is converted, within it's 535 // real or complex domain, to the precision of the other type. For example, 536 // when combining a "long double" with a "double _Complex", the 537 // "double _Complex" is promoted to "long double _Complex". 538 int order = Context.getFloatingTypeOrder(lhs, rhs); 539 540 // If both are complex, just cast to the more precise type. 541 if (LHSComplexFloat && RHSComplexFloat) { 542 if (order > 0) { 543 // _Complex float -> _Complex double 544 rhsExpr = ImpCastExprToType(rhsExpr.take(), lhs, CK_FloatingComplexCast); 545 return lhs; 546 547 } else if (order < 0) { 548 // _Complex float -> _Complex double 549 if (!isCompAssign) 550 lhsExpr = ImpCastExprToType(lhsExpr.take(), rhs, CK_FloatingComplexCast); 551 return rhs; 552 } 553 return lhs; 554 } 555 556 // If just the LHS is complex, the RHS needs to be converted, 557 // and the LHS might need to be promoted. 558 if (LHSComplexFloat) { 559 if (order > 0) { // LHS is wider 560 // float -> _Complex double 561 QualType fp = cast<ComplexType>(lhs)->getElementType(); 562 rhsExpr = ImpCastExprToType(rhsExpr.take(), fp, CK_FloatingCast); 563 rhsExpr = ImpCastExprToType(rhsExpr.take(), lhs, CK_FloatingRealToComplex); 564 return lhs; 565 } 566 567 // RHS is at least as wide. Find its corresponding complex type. 568 QualType result = (order == 0 ? lhs : Context.getComplexType(rhs)); 569 570 // double -> _Complex double 571 rhsExpr = ImpCastExprToType(rhsExpr.take(), result, CK_FloatingRealToComplex); 572 573 // _Complex float -> _Complex double 574 if (!isCompAssign && order < 0) 575 lhsExpr = ImpCastExprToType(lhsExpr.take(), result, CK_FloatingComplexCast); 576 577 return result; 578 } 579 580 // Just the RHS is complex, so the LHS needs to be converted 581 // and the RHS might need to be promoted. 582 assert(RHSComplexFloat); 583 584 if (order < 0) { // RHS is wider 585 // float -> _Complex double 586 if (!isCompAssign) { 587 QualType fp = cast<ComplexType>(rhs)->getElementType(); 588 lhsExpr = ImpCastExprToType(lhsExpr.take(), fp, CK_FloatingCast); 589 lhsExpr = ImpCastExprToType(lhsExpr.take(), rhs, CK_FloatingRealToComplex); 590 } 591 return rhs; 592 } 593 594 // LHS is at least as wide. Find its corresponding complex type. 595 QualType result = (order == 0 ? rhs : Context.getComplexType(lhs)); 596 597 // double -> _Complex double 598 if (!isCompAssign) 599 lhsExpr = ImpCastExprToType(lhsExpr.take(), result, CK_FloatingRealToComplex); 600 601 // _Complex float -> _Complex double 602 if (order > 0) 603 rhsExpr = ImpCastExprToType(rhsExpr.take(), result, CK_FloatingComplexCast); 604 605 return result; 606 } 607 608 // Now handle "real" floating types (i.e. float, double, long double). 609 bool LHSFloat = lhs->isRealFloatingType(); 610 bool RHSFloat = rhs->isRealFloatingType(); 611 if (LHSFloat || RHSFloat) { 612 // If we have two real floating types, convert the smaller operand 613 // to the bigger result. 614 if (LHSFloat && RHSFloat) { 615 int order = Context.getFloatingTypeOrder(lhs, rhs); 616 if (order > 0) { 617 rhsExpr = ImpCastExprToType(rhsExpr.take(), lhs, CK_FloatingCast); 618 return lhs; 619 } 620 621 assert(order < 0 && "illegal float comparison"); 622 if (!isCompAssign) 623 lhsExpr = ImpCastExprToType(lhsExpr.take(), rhs, CK_FloatingCast); 624 return rhs; 625 } 626 627 // If we have an integer operand, the result is the real floating type. 628 if (LHSFloat) { 629 if (rhs->isIntegerType()) { 630 // Convert rhs to the lhs floating point type. 631 rhsExpr = ImpCastExprToType(rhsExpr.take(), lhs, CK_IntegralToFloating); 632 return lhs; 633 } 634 635 // Convert both sides to the appropriate complex float. 636 assert(rhs->isComplexIntegerType()); 637 QualType result = Context.getComplexType(lhs); 638 639 // _Complex int -> _Complex float 640 rhsExpr = ImpCastExprToType(rhsExpr.take(), result, CK_IntegralComplexToFloatingComplex); 641 642 // float -> _Complex float 643 if (!isCompAssign) 644 lhsExpr = ImpCastExprToType(lhsExpr.take(), result, CK_FloatingRealToComplex); 645 646 return result; 647 } 648 649 assert(RHSFloat); 650 if (lhs->isIntegerType()) { 651 // Convert lhs to the rhs floating point type. 652 if (!isCompAssign) 653 lhsExpr = ImpCastExprToType(lhsExpr.take(), rhs, CK_IntegralToFloating); 654 return rhs; 655 } 656 657 // Convert both sides to the appropriate complex float. 658 assert(lhs->isComplexIntegerType()); 659 QualType result = Context.getComplexType(rhs); 660 661 // _Complex int -> _Complex float 662 if (!isCompAssign) 663 lhsExpr = ImpCastExprToType(lhsExpr.take(), result, CK_IntegralComplexToFloatingComplex); 664 665 // float -> _Complex float 666 rhsExpr = ImpCastExprToType(rhsExpr.take(), result, CK_FloatingRealToComplex); 667 668 return result; 669 } 670 671 // Handle GCC complex int extension. 672 // FIXME: if the operands are (int, _Complex long), we currently 673 // don't promote the complex. Also, signedness? 674 const ComplexType *lhsComplexInt = lhs->getAsComplexIntegerType(); 675 const ComplexType *rhsComplexInt = rhs->getAsComplexIntegerType(); 676 if (lhsComplexInt && rhsComplexInt) { 677 int order = Context.getIntegerTypeOrder(lhsComplexInt->getElementType(), 678 rhsComplexInt->getElementType()); 679 assert(order && "inequal types with equal element ordering"); 680 if (order > 0) { 681 // _Complex int -> _Complex long 682 rhsExpr = ImpCastExprToType(rhsExpr.take(), lhs, CK_IntegralComplexCast); 683 return lhs; 684 } 685 686 if (!isCompAssign) 687 lhsExpr = ImpCastExprToType(lhsExpr.take(), rhs, CK_IntegralComplexCast); 688 return rhs; 689 } else if (lhsComplexInt) { 690 // int -> _Complex int 691 rhsExpr = ImpCastExprToType(rhsExpr.take(), lhs, CK_IntegralRealToComplex); 692 return lhs; 693 } else if (rhsComplexInt) { 694 // int -> _Complex int 695 if (!isCompAssign) 696 lhsExpr = ImpCastExprToType(lhsExpr.take(), rhs, CK_IntegralRealToComplex); 697 return rhs; 698 } 699 700 // Finally, we have two differing integer types. 701 // The rules for this case are in C99 6.3.1.8 702 int compare = Context.getIntegerTypeOrder(lhs, rhs); 703 bool lhsSigned = lhs->hasSignedIntegerRepresentation(), 704 rhsSigned = rhs->hasSignedIntegerRepresentation(); 705 if (lhsSigned == rhsSigned) { 706 // Same signedness; use the higher-ranked type 707 if (compare >= 0) { 708 rhsExpr = ImpCastExprToType(rhsExpr.take(), lhs, CK_IntegralCast); 709 return lhs; 710 } else if (!isCompAssign) 711 lhsExpr = ImpCastExprToType(lhsExpr.take(), rhs, CK_IntegralCast); 712 return rhs; 713 } else if (compare != (lhsSigned ? 1 : -1)) { 714 // The unsigned type has greater than or equal rank to the 715 // signed type, so use the unsigned type 716 if (rhsSigned) { 717 rhsExpr = ImpCastExprToType(rhsExpr.take(), lhs, CK_IntegralCast); 718 return lhs; 719 } else if (!isCompAssign) 720 lhsExpr = ImpCastExprToType(lhsExpr.take(), rhs, CK_IntegralCast); 721 return rhs; 722 } else if (Context.getIntWidth(lhs) != Context.getIntWidth(rhs)) { 723 // The two types are different widths; if we are here, that 724 // means the signed type is larger than the unsigned type, so 725 // use the signed type. 726 if (lhsSigned) { 727 rhsExpr = ImpCastExprToType(rhsExpr.take(), lhs, CK_IntegralCast); 728 return lhs; 729 } else if (!isCompAssign) 730 lhsExpr = ImpCastExprToType(lhsExpr.take(), rhs, CK_IntegralCast); 731 return rhs; 732 } else { 733 // The signed type is higher-ranked than the unsigned type, 734 // but isn't actually any bigger (like unsigned int and long 735 // on most 32-bit systems). Use the unsigned type corresponding 736 // to the signed type. 737 QualType result = 738 Context.getCorrespondingUnsignedType(lhsSigned ? lhs : rhs); 739 rhsExpr = ImpCastExprToType(rhsExpr.take(), result, CK_IntegralCast); 740 if (!isCompAssign) 741 lhsExpr = ImpCastExprToType(lhsExpr.take(), result, CK_IntegralCast); 742 return result; 743 } 744} 745 746//===----------------------------------------------------------------------===// 747// Semantic Analysis for various Expression Types 748//===----------------------------------------------------------------------===// 749 750 751ExprResult 752Sema::ActOnGenericSelectionExpr(SourceLocation KeyLoc, 753 SourceLocation DefaultLoc, 754 SourceLocation RParenLoc, 755 Expr *ControllingExpr, 756 MultiTypeArg types, 757 MultiExprArg exprs) { 758 unsigned NumAssocs = types.size(); 759 assert(NumAssocs == exprs.size()); 760 761 ParsedType *ParsedTypes = types.release(); 762 Expr **Exprs = exprs.release(); 763 764 TypeSourceInfo **Types = new TypeSourceInfo*[NumAssocs]; 765 for (unsigned i = 0; i < NumAssocs; ++i) { 766 if (ParsedTypes[i]) 767 (void) GetTypeFromParser(ParsedTypes[i], &Types[i]); 768 else 769 Types[i] = 0; 770 } 771 772 ExprResult ER = CreateGenericSelectionExpr(KeyLoc, DefaultLoc, RParenLoc, 773 ControllingExpr, Types, Exprs, 774 NumAssocs); 775 delete [] Types; 776 return ER; 777} 778 779ExprResult 780Sema::CreateGenericSelectionExpr(SourceLocation KeyLoc, 781 SourceLocation DefaultLoc, 782 SourceLocation RParenLoc, 783 Expr *ControllingExpr, 784 TypeSourceInfo **Types, 785 Expr **Exprs, 786 unsigned NumAssocs) { 787 bool TypeErrorFound = false, 788 IsResultDependent = ControllingExpr->isTypeDependent(), 789 ContainsUnexpandedParameterPack 790 = ControllingExpr->containsUnexpandedParameterPack(); 791 792 for (unsigned i = 0; i < NumAssocs; ++i) { 793 if (Exprs[i]->containsUnexpandedParameterPack()) 794 ContainsUnexpandedParameterPack = true; 795 796 if (Types[i]) { 797 if (Types[i]->getType()->containsUnexpandedParameterPack()) 798 ContainsUnexpandedParameterPack = true; 799 800 if (Types[i]->getType()->isDependentType()) { 801 IsResultDependent = true; 802 } else { 803 // C1X 6.5.1.1p2 "The type name in a generic association shall specify a 804 // complete object type other than a variably modified type." 805 unsigned D = 0; 806 if (Types[i]->getType()->isIncompleteType()) 807 D = diag::err_assoc_type_incomplete; 808 else if (!Types[i]->getType()->isObjectType()) 809 D = diag::err_assoc_type_nonobject; 810 else if (Types[i]->getType()->isVariablyModifiedType()) 811 D = diag::err_assoc_type_variably_modified; 812 813 if (D != 0) { 814 Diag(Types[i]->getTypeLoc().getBeginLoc(), D) 815 << Types[i]->getTypeLoc().getSourceRange() 816 << Types[i]->getType(); 817 TypeErrorFound = true; 818 } 819 820 // C1X 6.5.1.1p2 "No two generic associations in the same generic 821 // selection shall specify compatible types." 822 for (unsigned j = i+1; j < NumAssocs; ++j) 823 if (Types[j] && !Types[j]->getType()->isDependentType() && 824 Context.typesAreCompatible(Types[i]->getType(), 825 Types[j]->getType())) { 826 Diag(Types[j]->getTypeLoc().getBeginLoc(), 827 diag::err_assoc_compatible_types) 828 << Types[j]->getTypeLoc().getSourceRange() 829 << Types[j]->getType() 830 << Types[i]->getType(); 831 Diag(Types[i]->getTypeLoc().getBeginLoc(), 832 diag::note_compat_assoc) 833 << Types[i]->getTypeLoc().getSourceRange() 834 << Types[i]->getType(); 835 TypeErrorFound = true; 836 } 837 } 838 } 839 } 840 if (TypeErrorFound) 841 return ExprError(); 842 843 // If we determined that the generic selection is result-dependent, don't 844 // try to compute the result expression. 845 if (IsResultDependent) 846 return Owned(new (Context) GenericSelectionExpr( 847 Context, KeyLoc, ControllingExpr, 848 Types, Exprs, NumAssocs, DefaultLoc, 849 RParenLoc, ContainsUnexpandedParameterPack)); 850 851 llvm::SmallVector<unsigned, 1> CompatIndices; 852 unsigned DefaultIndex = -1U; 853 for (unsigned i = 0; i < NumAssocs; ++i) { 854 if (!Types[i]) 855 DefaultIndex = i; 856 else if (Context.typesAreCompatible(ControllingExpr->getType(), 857 Types[i]->getType())) 858 CompatIndices.push_back(i); 859 } 860 861 // C1X 6.5.1.1p2 "The controlling expression of a generic selection shall have 862 // type compatible with at most one of the types named in its generic 863 // association list." 864 if (CompatIndices.size() > 1) { 865 // We strip parens here because the controlling expression is typically 866 // parenthesized in macro definitions. 867 ControllingExpr = ControllingExpr->IgnoreParens(); 868 Diag(ControllingExpr->getLocStart(), diag::err_generic_sel_multi_match) 869 << ControllingExpr->getSourceRange() << ControllingExpr->getType() 870 << (unsigned) CompatIndices.size(); 871 for (llvm::SmallVector<unsigned, 1>::iterator I = CompatIndices.begin(), 872 E = CompatIndices.end(); I != E; ++I) { 873 Diag(Types[*I]->getTypeLoc().getBeginLoc(), 874 diag::note_compat_assoc) 875 << Types[*I]->getTypeLoc().getSourceRange() 876 << Types[*I]->getType(); 877 } 878 return ExprError(); 879 } 880 881 // C1X 6.5.1.1p2 "If a generic selection has no default generic association, 882 // its controlling expression shall have type compatible with exactly one of 883 // the types named in its generic association list." 884 if (DefaultIndex == -1U && CompatIndices.size() == 0) { 885 // We strip parens here because the controlling expression is typically 886 // parenthesized in macro definitions. 887 ControllingExpr = ControllingExpr->IgnoreParens(); 888 Diag(ControllingExpr->getLocStart(), diag::err_generic_sel_no_match) 889 << ControllingExpr->getSourceRange() << ControllingExpr->getType(); 890 return ExprError(); 891 } 892 893 // C1X 6.5.1.1p3 "If a generic selection has a generic association with a 894 // type name that is compatible with the type of the controlling expression, 895 // then the result expression of the generic selection is the expression 896 // in that generic association. Otherwise, the result expression of the 897 // generic selection is the expression in the default generic association." 898 unsigned ResultIndex = 899 CompatIndices.size() ? CompatIndices[0] : DefaultIndex; 900 901 return Owned(new (Context) GenericSelectionExpr( 902 Context, KeyLoc, ControllingExpr, 903 Types, Exprs, NumAssocs, DefaultLoc, 904 RParenLoc, ContainsUnexpandedParameterPack, 905 ResultIndex)); 906} 907 908/// ActOnStringLiteral - The specified tokens were lexed as pasted string 909/// fragments (e.g. "foo" "bar" L"baz"). The result string has to handle string 910/// concatenation ([C99 5.1.1.2, translation phase #6]), so it may come from 911/// multiple tokens. However, the common case is that StringToks points to one 912/// string. 913/// 914ExprResult 915Sema::ActOnStringLiteral(const Token *StringToks, unsigned NumStringToks) { 916 assert(NumStringToks && "Must have at least one string!"); 917 918 StringLiteralParser Literal(StringToks, NumStringToks, PP); 919 if (Literal.hadError) 920 return ExprError(); 921 922 llvm::SmallVector<SourceLocation, 4> StringTokLocs; 923 for (unsigned i = 0; i != NumStringToks; ++i) 924 StringTokLocs.push_back(StringToks[i].getLocation()); 925 926 QualType StrTy = Context.CharTy; 927 if (Literal.AnyWide) 928 StrTy = Context.getWCharType(); 929 else if (Literal.Pascal) 930 StrTy = Context.UnsignedCharTy; 931 932 // A C++ string literal has a const-qualified element type (C++ 2.13.4p1). 933 if (getLangOptions().CPlusPlus || getLangOptions().ConstStrings) 934 StrTy.addConst(); 935 936 // Get an array type for the string, according to C99 6.4.5. This includes 937 // the nul terminator character as well as the string length for pascal 938 // strings. 939 StrTy = Context.getConstantArrayType(StrTy, 940 llvm::APInt(32, Literal.GetNumStringChars()+1), 941 ArrayType::Normal, 0); 942 943 // Pass &StringTokLocs[0], StringTokLocs.size() to factory! 944 return Owned(StringLiteral::Create(Context, Literal.GetString(), 945 Literal.GetStringLength(), 946 Literal.AnyWide, Literal.Pascal, StrTy, 947 &StringTokLocs[0], 948 StringTokLocs.size())); 949} 950 951enum CaptureResult { 952 /// No capture is required. 953 CR_NoCapture, 954 955 /// A capture is required. 956 CR_Capture, 957 958 /// A by-ref capture is required. 959 CR_CaptureByRef, 960 961 /// An error occurred when trying to capture the given variable. 962 CR_Error 963}; 964 965/// Diagnose an uncapturable value reference. 966/// 967/// \param var - the variable referenced 968/// \param DC - the context which we couldn't capture through 969static CaptureResult 970diagnoseUncapturableValueReference(Sema &S, SourceLocation loc, 971 VarDecl *var, DeclContext *DC) { 972 switch (S.ExprEvalContexts.back().Context) { 973 case Sema::Unevaluated: 974 // The argument will never be evaluated, so don't complain. 975 return CR_NoCapture; 976 977 case Sema::PotentiallyEvaluated: 978 case Sema::PotentiallyEvaluatedIfUsed: 979 break; 980 981 case Sema::PotentiallyPotentiallyEvaluated: 982 // FIXME: delay these! 983 break; 984 } 985 986 // Don't diagnose about capture if we're not actually in code right 987 // now; in general, there are more appropriate places that will 988 // diagnose this. 989 if (!S.CurContext->isFunctionOrMethod()) return CR_NoCapture; 990 991 // Certain madnesses can happen with parameter declarations, which 992 // we want to ignore. 993 if (isa<ParmVarDecl>(var)) { 994 // - If the parameter still belongs to the translation unit, then 995 // we're actually just using one parameter in the declaration of 996 // the next. This is useful in e.g. VLAs. 997 if (isa<TranslationUnitDecl>(var->getDeclContext())) 998 return CR_NoCapture; 999 1000 // - This particular madness can happen in ill-formed default 1001 // arguments; claim it's okay and let downstream code handle it. 1002 if (S.CurContext == var->getDeclContext()->getParent()) 1003 return CR_NoCapture; 1004 } 1005 1006 DeclarationName functionName; 1007 if (FunctionDecl *fn = dyn_cast<FunctionDecl>(var->getDeclContext())) 1008 functionName = fn->getDeclName(); 1009 // FIXME: variable from enclosing block that we couldn't capture from! 1010 1011 S.Diag(loc, diag::err_reference_to_local_var_in_enclosing_function) 1012 << var->getIdentifier() << functionName; 1013 S.Diag(var->getLocation(), diag::note_local_variable_declared_here) 1014 << var->getIdentifier(); 1015 1016 return CR_Error; 1017} 1018 1019/// There is a well-formed capture at a particular scope level; 1020/// propagate it through all the nested blocks. 1021static CaptureResult propagateCapture(Sema &S, unsigned validScopeIndex, 1022 const BlockDecl::Capture &capture) { 1023 VarDecl *var = capture.getVariable(); 1024 1025 // Update all the inner blocks with the capture information. 1026 for (unsigned i = validScopeIndex + 1, e = S.FunctionScopes.size(); 1027 i != e; ++i) { 1028 BlockScopeInfo *innerBlock = cast<BlockScopeInfo>(S.FunctionScopes[i]); 1029 innerBlock->Captures.push_back( 1030 BlockDecl::Capture(capture.getVariable(), capture.isByRef(), 1031 /*nested*/ true, capture.getCopyExpr())); 1032 innerBlock->CaptureMap[var] = innerBlock->Captures.size(); // +1 1033 } 1034 1035 return capture.isByRef() ? CR_CaptureByRef : CR_Capture; 1036} 1037 1038/// shouldCaptureValueReference - Determine if a reference to the 1039/// given value in the current context requires a variable capture. 1040/// 1041/// This also keeps the captures set in the BlockScopeInfo records 1042/// up-to-date. 1043static CaptureResult shouldCaptureValueReference(Sema &S, SourceLocation loc, 1044 ValueDecl *value) { 1045 // Only variables ever require capture. 1046 VarDecl *var = dyn_cast<VarDecl>(value); 1047 if (!var) return CR_NoCapture; 1048 1049 // Fast path: variables from the current context never require capture. 1050 DeclContext *DC = S.CurContext; 1051 if (var->getDeclContext() == DC) return CR_NoCapture; 1052 1053 // Only variables with local storage require capture. 1054 // FIXME: What about 'const' variables in C++? 1055 if (!var->hasLocalStorage()) return CR_NoCapture; 1056 1057 // Otherwise, we need to capture. 1058 1059 unsigned functionScopesIndex = S.FunctionScopes.size() - 1; 1060 do { 1061 // Only blocks (and eventually C++0x closures) can capture; other 1062 // scopes don't work. 1063 if (!isa<BlockDecl>(DC)) 1064 return diagnoseUncapturableValueReference(S, loc, var, DC); 1065 1066 BlockScopeInfo *blockScope = 1067 cast<BlockScopeInfo>(S.FunctionScopes[functionScopesIndex]); 1068 assert(blockScope->TheDecl == static_cast<BlockDecl*>(DC)); 1069 1070 // Check whether we've already captured it in this block. If so, 1071 // we're done. 1072 if (unsigned indexPlus1 = blockScope->CaptureMap[var]) 1073 return propagateCapture(S, functionScopesIndex, 1074 blockScope->Captures[indexPlus1 - 1]); 1075 1076 functionScopesIndex--; 1077 DC = cast<BlockDecl>(DC)->getDeclContext(); 1078 } while (var->getDeclContext() != DC); 1079 1080 // Okay, we descended all the way to the block that defines the variable. 1081 // Actually try to capture it. 1082 QualType type = var->getType(); 1083 1084 // Prohibit variably-modified types. 1085 if (type->isVariablyModifiedType()) { 1086 S.Diag(loc, diag::err_ref_vm_type); 1087 S.Diag(var->getLocation(), diag::note_declared_at); 1088 return CR_Error; 1089 } 1090 1091 // Prohibit arrays, even in __block variables, but not references to 1092 // them. 1093 if (type->isArrayType()) { 1094 S.Diag(loc, diag::err_ref_array_type); 1095 S.Diag(var->getLocation(), diag::note_declared_at); 1096 return CR_Error; 1097 } 1098 1099 S.MarkDeclarationReferenced(loc, var); 1100 1101 // The BlocksAttr indicates the variable is bound by-reference. 1102 bool byRef = var->hasAttr<BlocksAttr>(); 1103 1104 // Build a copy expression. 1105 Expr *copyExpr = 0; 1106 if (!byRef && S.getLangOptions().CPlusPlus && 1107 !type->isDependentType() && type->isStructureOrClassType()) { 1108 // According to the blocks spec, the capture of a variable from 1109 // the stack requires a const copy constructor. This is not true 1110 // of the copy/move done to move a __block variable to the heap. 1111 type.addConst(); 1112 1113 Expr *declRef = new (S.Context) DeclRefExpr(var, type, VK_LValue, loc); 1114 ExprResult result = 1115 S.PerformCopyInitialization( 1116 InitializedEntity::InitializeBlock(var->getLocation(), 1117 type, false), 1118 loc, S.Owned(declRef)); 1119 1120 // Build a full-expression copy expression if initialization 1121 // succeeded and used a non-trivial constructor. Recover from 1122 // errors by pretending that the copy isn't necessary. 1123 if (!result.isInvalid() && 1124 !cast<CXXConstructExpr>(result.get())->getConstructor()->isTrivial()) { 1125 result = S.MaybeCreateExprWithCleanups(result); 1126 copyExpr = result.take(); 1127 } 1128 } 1129 1130 // We're currently at the declarer; go back to the closure. 1131 functionScopesIndex++; 1132 BlockScopeInfo *blockScope = 1133 cast<BlockScopeInfo>(S.FunctionScopes[functionScopesIndex]); 1134 1135 // Build a valid capture in this scope. 1136 blockScope->Captures.push_back( 1137 BlockDecl::Capture(var, byRef, /*nested*/ false, copyExpr)); 1138 blockScope->CaptureMap[var] = blockScope->Captures.size(); // +1 1139 1140 // Propagate that to inner captures if necessary. 1141 return propagateCapture(S, functionScopesIndex, 1142 blockScope->Captures.back()); 1143} 1144 1145static ExprResult BuildBlockDeclRefExpr(Sema &S, ValueDecl *vd, 1146 const DeclarationNameInfo &NameInfo, 1147 bool byRef) { 1148 assert(isa<VarDecl>(vd) && "capturing non-variable"); 1149 1150 VarDecl *var = cast<VarDecl>(vd); 1151 assert(var->hasLocalStorage() && "capturing non-local"); 1152 assert(byRef == var->hasAttr<BlocksAttr>() && "byref set wrong"); 1153 1154 QualType exprType = var->getType().getNonReferenceType(); 1155 1156 BlockDeclRefExpr *BDRE; 1157 if (!byRef) { 1158 // The variable will be bound by copy; make it const within the 1159 // closure, but record that this was done in the expression. 1160 bool constAdded = !exprType.isConstQualified(); 1161 exprType.addConst(); 1162 1163 BDRE = new (S.Context) BlockDeclRefExpr(var, exprType, VK_LValue, 1164 NameInfo.getLoc(), false, 1165 constAdded); 1166 } else { 1167 BDRE = new (S.Context) BlockDeclRefExpr(var, exprType, VK_LValue, 1168 NameInfo.getLoc(), true); 1169 } 1170 1171 return S.Owned(BDRE); 1172} 1173 1174ExprResult 1175Sema::BuildDeclRefExpr(ValueDecl *D, QualType Ty, ExprValueKind VK, 1176 SourceLocation Loc, 1177 const CXXScopeSpec *SS) { 1178 DeclarationNameInfo NameInfo(D->getDeclName(), Loc); 1179 return BuildDeclRefExpr(D, Ty, VK, NameInfo, SS); 1180} 1181 1182/// BuildDeclRefExpr - Build an expression that references a 1183/// declaration that does not require a closure capture. 1184ExprResult 1185Sema::BuildDeclRefExpr(ValueDecl *D, QualType Ty, ExprValueKind VK, 1186 const DeclarationNameInfo &NameInfo, 1187 const CXXScopeSpec *SS) { 1188 MarkDeclarationReferenced(NameInfo.getLoc(), D); 1189 1190 Expr *E = DeclRefExpr::Create(Context, 1191 SS? SS->getWithLocInContext(Context) 1192 : NestedNameSpecifierLoc(), 1193 D, NameInfo, Ty, VK); 1194 1195 // Just in case we're building an illegal pointer-to-member. 1196 if (isa<FieldDecl>(D) && cast<FieldDecl>(D)->getBitWidth()) 1197 E->setObjectKind(OK_BitField); 1198 1199 return Owned(E); 1200} 1201 1202static ExprResult 1203BuildFieldReferenceExpr(Sema &S, Expr *BaseExpr, bool IsArrow, 1204 const CXXScopeSpec &SS, FieldDecl *Field, 1205 DeclAccessPair FoundDecl, 1206 const DeclarationNameInfo &MemberNameInfo); 1207 1208ExprResult 1209Sema::BuildAnonymousStructUnionMemberReference(const CXXScopeSpec &SS, 1210 SourceLocation loc, 1211 IndirectFieldDecl *indirectField, 1212 Expr *baseObjectExpr, 1213 SourceLocation opLoc) { 1214 // First, build the expression that refers to the base object. 1215 1216 bool baseObjectIsPointer = false; 1217 Qualifiers baseQuals; 1218 1219 // Case 1: the base of the indirect field is not a field. 1220 VarDecl *baseVariable = indirectField->getVarDecl(); 1221 CXXScopeSpec EmptySS; 1222 if (baseVariable) { 1223 assert(baseVariable->getType()->isRecordType()); 1224 1225 // In principle we could have a member access expression that 1226 // accesses an anonymous struct/union that's a static member of 1227 // the base object's class. However, under the current standard, 1228 // static data members cannot be anonymous structs or unions. 1229 // Supporting this is as easy as building a MemberExpr here. 1230 assert(!baseObjectExpr && "anonymous struct/union is static data member?"); 1231 1232 DeclarationNameInfo baseNameInfo(DeclarationName(), loc); 1233 1234 ExprResult result = 1235 BuildDeclarationNameExpr(EmptySS, baseNameInfo, baseVariable); 1236 if (result.isInvalid()) return ExprError(); 1237 1238 baseObjectExpr = result.take(); 1239 baseObjectIsPointer = false; 1240 baseQuals = baseObjectExpr->getType().getQualifiers(); 1241 1242 // Case 2: the base of the indirect field is a field and the user 1243 // wrote a member expression. 1244 } else if (baseObjectExpr) { 1245 // The caller provided the base object expression. Determine 1246 // whether its a pointer and whether it adds any qualifiers to the 1247 // anonymous struct/union fields we're looking into. 1248 QualType objectType = baseObjectExpr->getType(); 1249 1250 if (const PointerType *ptr = objectType->getAs<PointerType>()) { 1251 baseObjectIsPointer = true; 1252 objectType = ptr->getPointeeType(); 1253 } else { 1254 baseObjectIsPointer = false; 1255 } 1256 baseQuals = objectType.getQualifiers(); 1257 1258 // Case 3: the base of the indirect field is a field and we should 1259 // build an implicit member access. 1260 } else { 1261 // We've found a member of an anonymous struct/union that is 1262 // inside a non-anonymous struct/union, so in a well-formed 1263 // program our base object expression is "this". 1264 CXXMethodDecl *method = tryCaptureCXXThis(); 1265 if (!method) { 1266 Diag(loc, diag::err_invalid_member_use_in_static_method) 1267 << indirectField->getDeclName(); 1268 return ExprError(); 1269 } 1270 1271 // Our base object expression is "this". 1272 baseObjectExpr = 1273 new (Context) CXXThisExpr(loc, method->getThisType(Context), 1274 /*isImplicit=*/ true); 1275 baseObjectIsPointer = true; 1276 baseQuals = Qualifiers::fromCVRMask(method->getTypeQualifiers()); 1277 } 1278 1279 // Build the implicit member references to the field of the 1280 // anonymous struct/union. 1281 Expr *result = baseObjectExpr; 1282 IndirectFieldDecl::chain_iterator 1283 FI = indirectField->chain_begin(), FEnd = indirectField->chain_end(); 1284 1285 // Build the first member access in the chain with full information. 1286 if (!baseVariable) { 1287 FieldDecl *field = cast<FieldDecl>(*FI); 1288 1289 // FIXME: use the real found-decl info! 1290 DeclAccessPair foundDecl = DeclAccessPair::make(field, field->getAccess()); 1291 1292 // Make a nameInfo that properly uses the anonymous name. 1293 DeclarationNameInfo memberNameInfo(field->getDeclName(), loc); 1294 1295 result = BuildFieldReferenceExpr(*this, result, baseObjectIsPointer, 1296 EmptySS, field, foundDecl, 1297 memberNameInfo).take(); 1298 baseObjectIsPointer = false; 1299 1300 // FIXME: check qualified member access 1301 } 1302 1303 // In all cases, we should now skip the first declaration in the chain. 1304 ++FI; 1305 1306 while (FI != FEnd) { 1307 FieldDecl *field = cast<FieldDecl>(*FI++); 1308 1309 // FIXME: these are somewhat meaningless 1310 DeclarationNameInfo memberNameInfo(field->getDeclName(), loc); 1311 DeclAccessPair foundDecl = DeclAccessPair::make(field, field->getAccess()); 1312 1313 result = BuildFieldReferenceExpr(*this, result, /*isarrow*/ false, 1314 (FI == FEnd? SS : EmptySS), field, 1315 foundDecl, memberNameInfo) 1316 .take(); 1317 } 1318 1319 return Owned(result); 1320} 1321 1322/// Decomposes the given name into a DeclarationNameInfo, its location, and 1323/// possibly a list of template arguments. 1324/// 1325/// If this produces template arguments, it is permitted to call 1326/// DecomposeTemplateName. 1327/// 1328/// This actually loses a lot of source location information for 1329/// non-standard name kinds; we should consider preserving that in 1330/// some way. 1331static void DecomposeUnqualifiedId(Sema &SemaRef, 1332 const UnqualifiedId &Id, 1333 TemplateArgumentListInfo &Buffer, 1334 DeclarationNameInfo &NameInfo, 1335 const TemplateArgumentListInfo *&TemplateArgs) { 1336 if (Id.getKind() == UnqualifiedId::IK_TemplateId) { 1337 Buffer.setLAngleLoc(Id.TemplateId->LAngleLoc); 1338 Buffer.setRAngleLoc(Id.TemplateId->RAngleLoc); 1339 1340 ASTTemplateArgsPtr TemplateArgsPtr(SemaRef, 1341 Id.TemplateId->getTemplateArgs(), 1342 Id.TemplateId->NumArgs); 1343 SemaRef.translateTemplateArguments(TemplateArgsPtr, Buffer); 1344 TemplateArgsPtr.release(); 1345 1346 TemplateName TName = Id.TemplateId->Template.get(); 1347 SourceLocation TNameLoc = Id.TemplateId->TemplateNameLoc; 1348 NameInfo = SemaRef.Context.getNameForTemplate(TName, TNameLoc); 1349 TemplateArgs = &Buffer; 1350 } else { 1351 NameInfo = SemaRef.GetNameFromUnqualifiedId(Id); 1352 TemplateArgs = 0; 1353 } 1354} 1355 1356/// Determines if the given class is provably not derived from all of 1357/// the prospective base classes. 1358static bool IsProvablyNotDerivedFrom(Sema &SemaRef, 1359 CXXRecordDecl *Record, 1360 const llvm::SmallPtrSet<CXXRecordDecl*, 4> &Bases) { 1361 if (Bases.count(Record->getCanonicalDecl())) 1362 return false; 1363 1364 RecordDecl *RD = Record->getDefinition(); 1365 if (!RD) return false; 1366 Record = cast<CXXRecordDecl>(RD); 1367 1368 for (CXXRecordDecl::base_class_iterator I = Record->bases_begin(), 1369 E = Record->bases_end(); I != E; ++I) { 1370 CanQualType BaseT = SemaRef.Context.getCanonicalType((*I).getType()); 1371 CanQual<RecordType> BaseRT = BaseT->getAs<RecordType>(); 1372 if (!BaseRT) return false; 1373 1374 CXXRecordDecl *BaseRecord = cast<CXXRecordDecl>(BaseRT->getDecl()); 1375 if (!IsProvablyNotDerivedFrom(SemaRef, BaseRecord, Bases)) 1376 return false; 1377 } 1378 1379 return true; 1380} 1381 1382enum IMAKind { 1383 /// The reference is definitely not an instance member access. 1384 IMA_Static, 1385 1386 /// The reference may be an implicit instance member access. 1387 IMA_Mixed, 1388 1389 /// The reference may be to an instance member, but it is invalid if 1390 /// so, because the context is not an instance method. 1391 IMA_Mixed_StaticContext, 1392 1393 /// The reference may be to an instance member, but it is invalid if 1394 /// so, because the context is from an unrelated class. 1395 IMA_Mixed_Unrelated, 1396 1397 /// The reference is definitely an implicit instance member access. 1398 IMA_Instance, 1399 1400 /// The reference may be to an unresolved using declaration. 1401 IMA_Unresolved, 1402 1403 /// The reference may be to an unresolved using declaration and the 1404 /// context is not an instance method. 1405 IMA_Unresolved_StaticContext, 1406 1407 /// All possible referrents are instance members and the current 1408 /// context is not an instance method. 1409 IMA_Error_StaticContext, 1410 1411 /// All possible referrents are instance members of an unrelated 1412 /// class. 1413 IMA_Error_Unrelated 1414}; 1415 1416/// The given lookup names class member(s) and is not being used for 1417/// an address-of-member expression. Classify the type of access 1418/// according to whether it's possible that this reference names an 1419/// instance member. This is best-effort; it is okay to 1420/// conservatively answer "yes", in which case some errors will simply 1421/// not be caught until template-instantiation. 1422static IMAKind ClassifyImplicitMemberAccess(Sema &SemaRef, 1423 const LookupResult &R) { 1424 assert(!R.empty() && (*R.begin())->isCXXClassMember()); 1425 1426 DeclContext *DC = SemaRef.getFunctionLevelDeclContext(); 1427 bool isStaticContext = 1428 (!isa<CXXMethodDecl>(DC) || 1429 cast<CXXMethodDecl>(DC)->isStatic()); 1430 1431 if (R.isUnresolvableResult()) 1432 return isStaticContext ? IMA_Unresolved_StaticContext : IMA_Unresolved; 1433 1434 // Collect all the declaring classes of instance members we find. 1435 bool hasNonInstance = false; 1436 bool hasField = false; 1437 llvm::SmallPtrSet<CXXRecordDecl*, 4> Classes; 1438 for (LookupResult::iterator I = R.begin(), E = R.end(); I != E; ++I) { 1439 NamedDecl *D = *I; 1440 1441 if (D->isCXXInstanceMember()) { 1442 if (dyn_cast<FieldDecl>(D)) 1443 hasField = true; 1444 1445 CXXRecordDecl *R = cast<CXXRecordDecl>(D->getDeclContext()); 1446 Classes.insert(R->getCanonicalDecl()); 1447 } 1448 else 1449 hasNonInstance = true; 1450 } 1451 1452 // If we didn't find any instance members, it can't be an implicit 1453 // member reference. 1454 if (Classes.empty()) 1455 return IMA_Static; 1456 1457 // If the current context is not an instance method, it can't be 1458 // an implicit member reference. 1459 if (isStaticContext) { 1460 if (hasNonInstance) 1461 return IMA_Mixed_StaticContext; 1462 1463 if (SemaRef.getLangOptions().CPlusPlus0x && hasField) { 1464 // C++0x [expr.prim.general]p10: 1465 // An id-expression that denotes a non-static data member or non-static 1466 // member function of a class can only be used: 1467 // (...) 1468 // - if that id-expression denotes a non-static data member and it appears in an unevaluated operand. 1469 const Sema::ExpressionEvaluationContextRecord& record = SemaRef.ExprEvalContexts.back(); 1470 bool isUnevaluatedExpression = record.Context == Sema::Unevaluated; 1471 if (isUnevaluatedExpression) 1472 return IMA_Mixed_StaticContext; 1473 } 1474 1475 return IMA_Error_StaticContext; 1476 } 1477 1478 CXXRecordDecl * 1479 contextClass = cast<CXXMethodDecl>(DC)->getParent()->getCanonicalDecl(); 1480 1481 // [class.mfct.non-static]p3: 1482 // ...is used in the body of a non-static member function of class X, 1483 // if name lookup (3.4.1) resolves the name in the id-expression to a 1484 // non-static non-type member of some class C [...] 1485 // ...if C is not X or a base class of X, the class member access expression 1486 // is ill-formed. 1487 if (R.getNamingClass() && 1488 contextClass != R.getNamingClass()->getCanonicalDecl() && 1489 contextClass->isProvablyNotDerivedFrom(R.getNamingClass())) 1490 return (hasNonInstance ? IMA_Mixed_Unrelated : IMA_Error_Unrelated); 1491 1492 // If we can prove that the current context is unrelated to all the 1493 // declaring classes, it can't be an implicit member reference (in 1494 // which case it's an error if any of those members are selected). 1495 if (IsProvablyNotDerivedFrom(SemaRef, contextClass, Classes)) 1496 return (hasNonInstance ? IMA_Mixed_Unrelated : IMA_Error_Unrelated); 1497 1498 return (hasNonInstance ? IMA_Mixed : IMA_Instance); 1499} 1500 1501/// Diagnose a reference to a field with no object available. 1502static void DiagnoseInstanceReference(Sema &SemaRef, 1503 const CXXScopeSpec &SS, 1504 NamedDecl *rep, 1505 const DeclarationNameInfo &nameInfo) { 1506 SourceLocation Loc = nameInfo.getLoc(); 1507 SourceRange Range(Loc); 1508 if (SS.isSet()) Range.setBegin(SS.getRange().getBegin()); 1509 1510 if (isa<FieldDecl>(rep) || isa<IndirectFieldDecl>(rep)) { 1511 if (CXXMethodDecl *MD = dyn_cast<CXXMethodDecl>(SemaRef.CurContext)) { 1512 if (MD->isStatic()) { 1513 // "invalid use of member 'x' in static member function" 1514 SemaRef.Diag(Loc, diag::err_invalid_member_use_in_static_method) 1515 << Range << nameInfo.getName(); 1516 return; 1517 } 1518 } 1519 1520 SemaRef.Diag(Loc, diag::err_invalid_non_static_member_use) 1521 << nameInfo.getName() << Range; 1522 return; 1523 } 1524 1525 SemaRef.Diag(Loc, diag::err_member_call_without_object) << Range; 1526} 1527 1528/// Diagnose an empty lookup. 1529/// 1530/// \return false if new lookup candidates were found 1531bool Sema::DiagnoseEmptyLookup(Scope *S, CXXScopeSpec &SS, LookupResult &R, 1532 CorrectTypoContext CTC) { 1533 DeclarationName Name = R.getLookupName(); 1534 1535 unsigned diagnostic = diag::err_undeclared_var_use; 1536 unsigned diagnostic_suggest = diag::err_undeclared_var_use_suggest; 1537 if (Name.getNameKind() == DeclarationName::CXXOperatorName || 1538 Name.getNameKind() == DeclarationName::CXXLiteralOperatorName || 1539 Name.getNameKind() == DeclarationName::CXXConversionFunctionName) { 1540 diagnostic = diag::err_undeclared_use; 1541 diagnostic_suggest = diag::err_undeclared_use_suggest; 1542 } 1543 1544 // If the original lookup was an unqualified lookup, fake an 1545 // unqualified lookup. This is useful when (for example) the 1546 // original lookup would not have found something because it was a 1547 // dependent name. 1548 for (DeclContext *DC = SS.isEmpty() ? CurContext : 0; 1549 DC; DC = DC->getParent()) { 1550 if (isa<CXXRecordDecl>(DC)) { 1551 LookupQualifiedName(R, DC); 1552 1553 if (!R.empty()) { 1554 // Don't give errors about ambiguities in this lookup. 1555 R.suppressDiagnostics(); 1556 1557 CXXMethodDecl *CurMethod = dyn_cast<CXXMethodDecl>(CurContext); 1558 bool isInstance = CurMethod && 1559 CurMethod->isInstance() && 1560 DC == CurMethod->getParent(); 1561 1562 // Give a code modification hint to insert 'this->'. 1563 // TODO: fixit for inserting 'Base<T>::' in the other cases. 1564 // Actually quite difficult! 1565 if (isInstance) { 1566 UnresolvedLookupExpr *ULE = cast<UnresolvedLookupExpr>( 1567 CallsUndergoingInstantiation.back()->getCallee()); 1568 CXXMethodDecl *DepMethod = cast_or_null<CXXMethodDecl>( 1569 CurMethod->getInstantiatedFromMemberFunction()); 1570 if (DepMethod) { 1571 Diag(R.getNameLoc(), diagnostic) << Name 1572 << FixItHint::CreateInsertion(R.getNameLoc(), "this->"); 1573 QualType DepThisType = DepMethod->getThisType(Context); 1574 CXXThisExpr *DepThis = new (Context) CXXThisExpr( 1575 R.getNameLoc(), DepThisType, false); 1576 TemplateArgumentListInfo TList; 1577 if (ULE->hasExplicitTemplateArgs()) 1578 ULE->copyTemplateArgumentsInto(TList); 1579 1580 CXXScopeSpec SS; 1581 SS.Adopt(ULE->getQualifierLoc()); 1582 CXXDependentScopeMemberExpr *DepExpr = 1583 CXXDependentScopeMemberExpr::Create( 1584 Context, DepThis, DepThisType, true, SourceLocation(), 1585 SS.getWithLocInContext(Context), NULL, 1586 R.getLookupNameInfo(), &TList); 1587 CallsUndergoingInstantiation.back()->setCallee(DepExpr); 1588 } else { 1589 // FIXME: we should be able to handle this case too. It is correct 1590 // to add this-> here. This is a workaround for PR7947. 1591 Diag(R.getNameLoc(), diagnostic) << Name; 1592 } 1593 } else { 1594 Diag(R.getNameLoc(), diagnostic) << Name; 1595 } 1596 1597 // Do we really want to note all of these? 1598 for (LookupResult::iterator I = R.begin(), E = R.end(); I != E; ++I) 1599 Diag((*I)->getLocation(), diag::note_dependent_var_use); 1600 1601 // Tell the callee to try to recover. 1602 return false; 1603 } 1604 1605 R.clear(); 1606 } 1607 } 1608 1609 // We didn't find anything, so try to correct for a typo. 1610 DeclarationName Corrected; 1611 if (S && (Corrected = CorrectTypo(R, S, &SS, 0, false, CTC))) { 1612 if (!R.empty()) { 1613 if (isa<ValueDecl>(*R.begin()) || isa<FunctionTemplateDecl>(*R.begin())) { 1614 if (SS.isEmpty()) 1615 Diag(R.getNameLoc(), diagnostic_suggest) << Name << R.getLookupName() 1616 << FixItHint::CreateReplacement(R.getNameLoc(), 1617 R.getLookupName().getAsString()); 1618 else 1619 Diag(R.getNameLoc(), diag::err_no_member_suggest) 1620 << Name << computeDeclContext(SS, false) << R.getLookupName() 1621 << SS.getRange() 1622 << FixItHint::CreateReplacement(R.getNameLoc(), 1623 R.getLookupName().getAsString()); 1624 if (NamedDecl *ND = R.getAsSingle<NamedDecl>()) 1625 Diag(ND->getLocation(), diag::note_previous_decl) 1626 << ND->getDeclName(); 1627 1628 // Tell the callee to try to recover. 1629 return false; 1630 } 1631 1632 if (isa<TypeDecl>(*R.begin()) || isa<ObjCInterfaceDecl>(*R.begin())) { 1633 // FIXME: If we ended up with a typo for a type name or 1634 // Objective-C class name, we're in trouble because the parser 1635 // is in the wrong place to recover. Suggest the typo 1636 // correction, but don't make it a fix-it since we're not going 1637 // to recover well anyway. 1638 if (SS.isEmpty()) 1639 Diag(R.getNameLoc(), diagnostic_suggest) << Name << R.getLookupName(); 1640 else 1641 Diag(R.getNameLoc(), diag::err_no_member_suggest) 1642 << Name << computeDeclContext(SS, false) << R.getLookupName() 1643 << SS.getRange(); 1644 1645 // Don't try to recover; it won't work. 1646 return true; 1647 } 1648 } else { 1649 // FIXME: We found a keyword. Suggest it, but don't provide a fix-it 1650 // because we aren't able to recover. 1651 if (SS.isEmpty()) 1652 Diag(R.getNameLoc(), diagnostic_suggest) << Name << Corrected; 1653 else 1654 Diag(R.getNameLoc(), diag::err_no_member_suggest) 1655 << Name << computeDeclContext(SS, false) << Corrected 1656 << SS.getRange(); 1657 return true; 1658 } 1659 R.clear(); 1660 } 1661 1662 // Emit a special diagnostic for failed member lookups. 1663 // FIXME: computing the declaration context might fail here (?) 1664 if (!SS.isEmpty()) { 1665 Diag(R.getNameLoc(), diag::err_no_member) 1666 << Name << computeDeclContext(SS, false) 1667 << SS.getRange(); 1668 return true; 1669 } 1670 1671 // Give up, we can't recover. 1672 Diag(R.getNameLoc(), diagnostic) << Name; 1673 return true; 1674} 1675 1676ObjCPropertyDecl *Sema::canSynthesizeProvisionalIvar(IdentifierInfo *II) { 1677 ObjCMethodDecl *CurMeth = getCurMethodDecl(); 1678 ObjCInterfaceDecl *IDecl = CurMeth->getClassInterface(); 1679 if (!IDecl) 1680 return 0; 1681 ObjCImplementationDecl *ClassImpDecl = IDecl->getImplementation(); 1682 if (!ClassImpDecl) 1683 return 0; 1684 ObjCPropertyDecl *property = LookupPropertyDecl(IDecl, II); 1685 if (!property) 1686 return 0; 1687 if (ObjCPropertyImplDecl *PIDecl = ClassImpDecl->FindPropertyImplDecl(II)) 1688 if (PIDecl->getPropertyImplementation() == ObjCPropertyImplDecl::Dynamic || 1689 PIDecl->getPropertyIvarDecl()) 1690 return 0; 1691 return property; 1692} 1693 1694bool Sema::canSynthesizeProvisionalIvar(ObjCPropertyDecl *Property) { 1695 ObjCMethodDecl *CurMeth = getCurMethodDecl(); 1696 ObjCInterfaceDecl *IDecl = CurMeth->getClassInterface(); 1697 if (!IDecl) 1698 return false; 1699 ObjCImplementationDecl *ClassImpDecl = IDecl->getImplementation(); 1700 if (!ClassImpDecl) 1701 return false; 1702 if (ObjCPropertyImplDecl *PIDecl 1703 = ClassImpDecl->FindPropertyImplDecl(Property->getIdentifier())) 1704 if (PIDecl->getPropertyImplementation() == ObjCPropertyImplDecl::Dynamic || 1705 PIDecl->getPropertyIvarDecl()) 1706 return false; 1707 1708 return true; 1709} 1710 1711static ObjCIvarDecl *SynthesizeProvisionalIvar(Sema &SemaRef, 1712 LookupResult &Lookup, 1713 IdentifierInfo *II, 1714 SourceLocation NameLoc) { 1715 ObjCMethodDecl *CurMeth = SemaRef.getCurMethodDecl(); 1716 bool LookForIvars; 1717 if (Lookup.empty()) 1718 LookForIvars = true; 1719 else if (CurMeth->isClassMethod()) 1720 LookForIvars = false; 1721 else 1722 LookForIvars = (Lookup.isSingleResult() && 1723 Lookup.getFoundDecl()->isDefinedOutsideFunctionOrMethod() && 1724 (Lookup.getAsSingle<VarDecl>() != 0)); 1725 if (!LookForIvars) 1726 return 0; 1727 1728 ObjCInterfaceDecl *IDecl = CurMeth->getClassInterface(); 1729 if (!IDecl) 1730 return 0; 1731 ObjCImplementationDecl *ClassImpDecl = IDecl->getImplementation(); 1732 if (!ClassImpDecl) 1733 return 0; 1734 bool DynamicImplSeen = false; 1735 ObjCPropertyDecl *property = SemaRef.LookupPropertyDecl(IDecl, II); 1736 if (!property) 1737 return 0; 1738 if (ObjCPropertyImplDecl *PIDecl = ClassImpDecl->FindPropertyImplDecl(II)) { 1739 DynamicImplSeen = 1740 (PIDecl->getPropertyImplementation() == ObjCPropertyImplDecl::Dynamic); 1741 // property implementation has a designated ivar. No need to assume a new 1742 // one. 1743 if (!DynamicImplSeen && PIDecl->getPropertyIvarDecl()) 1744 return 0; 1745 } 1746 if (!DynamicImplSeen) { 1747 QualType PropType = SemaRef.Context.getCanonicalType(property->getType()); 1748 ObjCIvarDecl *Ivar = ObjCIvarDecl::Create(SemaRef.Context, ClassImpDecl, 1749 NameLoc, NameLoc, 1750 II, PropType, /*Dinfo=*/0, 1751 ObjCIvarDecl::Private, 1752 (Expr *)0, true); 1753 ClassImpDecl->addDecl(Ivar); 1754 IDecl->makeDeclVisibleInContext(Ivar, false); 1755 property->setPropertyIvarDecl(Ivar); 1756 return Ivar; 1757 } 1758 return 0; 1759} 1760 1761ExprResult Sema::ActOnIdExpression(Scope *S, 1762 CXXScopeSpec &SS, 1763 UnqualifiedId &Id, 1764 bool HasTrailingLParen, 1765 bool isAddressOfOperand) { 1766 assert(!(isAddressOfOperand && HasTrailingLParen) && 1767 "cannot be direct & operand and have a trailing lparen"); 1768 1769 if (SS.isInvalid()) 1770 return ExprError(); 1771 1772 TemplateArgumentListInfo TemplateArgsBuffer; 1773 1774 // Decompose the UnqualifiedId into the following data. 1775 DeclarationNameInfo NameInfo; 1776 const TemplateArgumentListInfo *TemplateArgs; 1777 DecomposeUnqualifiedId(*this, Id, TemplateArgsBuffer, NameInfo, TemplateArgs); 1778 1779 DeclarationName Name = NameInfo.getName(); 1780 IdentifierInfo *II = Name.getAsIdentifierInfo(); 1781 SourceLocation NameLoc = NameInfo.getLoc(); 1782 1783 // C++ [temp.dep.expr]p3: 1784 // An id-expression is type-dependent if it contains: 1785 // -- an identifier that was declared with a dependent type, 1786 // (note: handled after lookup) 1787 // -- a template-id that is dependent, 1788 // (note: handled in BuildTemplateIdExpr) 1789 // -- a conversion-function-id that specifies a dependent type, 1790 // -- a nested-name-specifier that contains a class-name that 1791 // names a dependent type. 1792 // Determine whether this is a member of an unknown specialization; 1793 // we need to handle these differently. 1794 bool DependentID = false; 1795 if (Name.getNameKind() == DeclarationName::CXXConversionFunctionName && 1796 Name.getCXXNameType()->isDependentType()) { 1797 DependentID = true; 1798 } else if (SS.isSet()) { 1799 if (DeclContext *DC = computeDeclContext(SS, false)) { 1800 if (RequireCompleteDeclContext(SS, DC)) 1801 return ExprError(); 1802 } else { 1803 DependentID = true; 1804 } 1805 } 1806 1807 if (DependentID) 1808 return ActOnDependentIdExpression(SS, NameInfo, isAddressOfOperand, 1809 TemplateArgs); 1810 1811 bool IvarLookupFollowUp = false; 1812 // Perform the required lookup. 1813 LookupResult R(*this, NameInfo, LookupOrdinaryName); 1814 if (TemplateArgs) { 1815 // Lookup the template name again to correctly establish the context in 1816 // which it was found. This is really unfortunate as we already did the 1817 // lookup to determine that it was a template name in the first place. If 1818 // this becomes a performance hit, we can work harder to preserve those 1819 // results until we get here but it's likely not worth it. 1820 bool MemberOfUnknownSpecialization; 1821 LookupTemplateName(R, S, SS, QualType(), /*EnteringContext=*/false, 1822 MemberOfUnknownSpecialization); 1823 1824 if (MemberOfUnknownSpecialization || 1825 (R.getResultKind() == LookupResult::NotFoundInCurrentInstantiation)) 1826 return ActOnDependentIdExpression(SS, NameInfo, isAddressOfOperand, 1827 TemplateArgs); 1828 } else { 1829 IvarLookupFollowUp = (!SS.isSet() && II && getCurMethodDecl()); 1830 LookupParsedName(R, S, &SS, !IvarLookupFollowUp); 1831 1832 // If the result might be in a dependent base class, this is a dependent 1833 // id-expression. 1834 if (R.getResultKind() == LookupResult::NotFoundInCurrentInstantiation) 1835 return ActOnDependentIdExpression(SS, NameInfo, isAddressOfOperand, 1836 TemplateArgs); 1837 1838 // If this reference is in an Objective-C method, then we need to do 1839 // some special Objective-C lookup, too. 1840 if (IvarLookupFollowUp) { 1841 ExprResult E(LookupInObjCMethod(R, S, II, true)); 1842 if (E.isInvalid()) 1843 return ExprError(); 1844 1845 if (Expr *Ex = E.takeAs<Expr>()) 1846 return Owned(Ex); 1847 1848 // Synthesize ivars lazily. 1849 if (getLangOptions().ObjCDefaultSynthProperties && 1850 getLangOptions().ObjCNonFragileABI2) { 1851 if (SynthesizeProvisionalIvar(*this, R, II, NameLoc)) { 1852 if (const ObjCPropertyDecl *Property = 1853 canSynthesizeProvisionalIvar(II)) { 1854 Diag(NameLoc, diag::warn_synthesized_ivar_access) << II; 1855 Diag(Property->getLocation(), diag::note_property_declare); 1856 } 1857 return ActOnIdExpression(S, SS, Id, HasTrailingLParen, 1858 isAddressOfOperand); 1859 } 1860 } 1861 // for further use, this must be set to false if in class method. 1862 IvarLookupFollowUp = getCurMethodDecl()->isInstanceMethod(); 1863 } 1864 } 1865 1866 if (R.isAmbiguous()) 1867 return ExprError(); 1868 1869 // Determine whether this name might be a candidate for 1870 // argument-dependent lookup. 1871 bool ADL = UseArgumentDependentLookup(SS, R, HasTrailingLParen); 1872 1873 if (R.empty() && !ADL) { 1874 // Otherwise, this could be an implicitly declared function reference (legal 1875 // in C90, extension in C99, forbidden in C++). 1876 if (HasTrailingLParen && II && !getLangOptions().CPlusPlus) { 1877 NamedDecl *D = ImplicitlyDefineFunction(NameLoc, *II, S); 1878 if (D) R.addDecl(D); 1879 } 1880 1881 // If this name wasn't predeclared and if this is not a function 1882 // call, diagnose the problem. 1883 if (R.empty()) { 1884 if (DiagnoseEmptyLookup(S, SS, R, CTC_Unknown)) 1885 return ExprError(); 1886 1887 assert(!R.empty() && 1888 "DiagnoseEmptyLookup returned false but added no results"); 1889 1890 // If we found an Objective-C instance variable, let 1891 // LookupInObjCMethod build the appropriate expression to 1892 // reference the ivar. 1893 if (ObjCIvarDecl *Ivar = R.getAsSingle<ObjCIvarDecl>()) { 1894 R.clear(); 1895 ExprResult E(LookupInObjCMethod(R, S, Ivar->getIdentifier())); 1896 assert(E.isInvalid() || E.get()); 1897 return move(E); 1898 } 1899 } 1900 } 1901 1902 // This is guaranteed from this point on. 1903 assert(!R.empty() || ADL); 1904 1905 // Check whether this might be a C++ implicit instance member access. 1906 // C++ [class.mfct.non-static]p3: 1907 // When an id-expression that is not part of a class member access 1908 // syntax and not used to form a pointer to member is used in the 1909 // body of a non-static member function of class X, if name lookup 1910 // resolves the name in the id-expression to a non-static non-type 1911 // member of some class C, the id-expression is transformed into a 1912 // class member access expression using (*this) as the 1913 // postfix-expression to the left of the . operator. 1914 // 1915 // But we don't actually need to do this for '&' operands if R 1916 // resolved to a function or overloaded function set, because the 1917 // expression is ill-formed if it actually works out to be a 1918 // non-static member function: 1919 // 1920 // C++ [expr.ref]p4: 1921 // Otherwise, if E1.E2 refers to a non-static member function. . . 1922 // [t]he expression can be used only as the left-hand operand of a 1923 // member function call. 1924 // 1925 // There are other safeguards against such uses, but it's important 1926 // to get this right here so that we don't end up making a 1927 // spuriously dependent expression if we're inside a dependent 1928 // instance method. 1929 if (!R.empty() && (*R.begin())->isCXXClassMember()) { 1930 bool MightBeImplicitMember; 1931 if (!isAddressOfOperand) 1932 MightBeImplicitMember = true; 1933 else if (!SS.isEmpty()) 1934 MightBeImplicitMember = false; 1935 else if (R.isOverloadedResult()) 1936 MightBeImplicitMember = false; 1937 else if (R.isUnresolvableResult()) 1938 MightBeImplicitMember = true; 1939 else 1940 MightBeImplicitMember = isa<FieldDecl>(R.getFoundDecl()) || 1941 isa<IndirectFieldDecl>(R.getFoundDecl()); 1942 1943 if (MightBeImplicitMember) 1944 return BuildPossibleImplicitMemberExpr(SS, R, TemplateArgs); 1945 } 1946 1947 if (TemplateArgs) 1948 return BuildTemplateIdExpr(SS, R, ADL, *TemplateArgs); 1949 1950 return BuildDeclarationNameExpr(SS, R, ADL); 1951} 1952 1953/// Builds an expression which might be an implicit member expression. 1954ExprResult 1955Sema::BuildPossibleImplicitMemberExpr(const CXXScopeSpec &SS, 1956 LookupResult &R, 1957 const TemplateArgumentListInfo *TemplateArgs) { 1958 switch (ClassifyImplicitMemberAccess(*this, R)) { 1959 case IMA_Instance: 1960 return BuildImplicitMemberExpr(SS, R, TemplateArgs, true); 1961 1962 case IMA_Mixed: 1963 case IMA_Mixed_Unrelated: 1964 case IMA_Unresolved: 1965 return BuildImplicitMemberExpr(SS, R, TemplateArgs, false); 1966 1967 case IMA_Static: 1968 case IMA_Mixed_StaticContext: 1969 case IMA_Unresolved_StaticContext: 1970 if (TemplateArgs) 1971 return BuildTemplateIdExpr(SS, R, false, *TemplateArgs); 1972 return BuildDeclarationNameExpr(SS, R, false); 1973 1974 case IMA_Error_StaticContext: 1975 case IMA_Error_Unrelated: 1976 DiagnoseInstanceReference(*this, SS, R.getRepresentativeDecl(), 1977 R.getLookupNameInfo()); 1978 return ExprError(); 1979 } 1980 1981 llvm_unreachable("unexpected instance member access kind"); 1982 return ExprError(); 1983} 1984 1985/// BuildQualifiedDeclarationNameExpr - Build a C++ qualified 1986/// declaration name, generally during template instantiation. 1987/// There's a large number of things which don't need to be done along 1988/// this path. 1989ExprResult 1990Sema::BuildQualifiedDeclarationNameExpr(CXXScopeSpec &SS, 1991 const DeclarationNameInfo &NameInfo) { 1992 DeclContext *DC; 1993 if (!(DC = computeDeclContext(SS, false)) || DC->isDependentContext()) 1994 return BuildDependentDeclRefExpr(SS, NameInfo, 0); 1995 1996 if (RequireCompleteDeclContext(SS, DC)) 1997 return ExprError(); 1998 1999 LookupResult R(*this, NameInfo, LookupOrdinaryName); 2000 LookupQualifiedName(R, DC); 2001 2002 if (R.isAmbiguous()) 2003 return ExprError(); 2004 2005 if (R.empty()) { 2006 Diag(NameInfo.getLoc(), diag::err_no_member) 2007 << NameInfo.getName() << DC << SS.getRange(); 2008 return ExprError(); 2009 } 2010 2011 return BuildDeclarationNameExpr(SS, R, /*ADL*/ false); 2012} 2013 2014/// LookupInObjCMethod - The parser has read a name in, and Sema has 2015/// detected that we're currently inside an ObjC method. Perform some 2016/// additional lookup. 2017/// 2018/// Ideally, most of this would be done by lookup, but there's 2019/// actually quite a lot of extra work involved. 2020/// 2021/// Returns a null sentinel to indicate trivial success. 2022ExprResult 2023Sema::LookupInObjCMethod(LookupResult &Lookup, Scope *S, 2024 IdentifierInfo *II, bool AllowBuiltinCreation) { 2025 SourceLocation Loc = Lookup.getNameLoc(); 2026 ObjCMethodDecl *CurMethod = getCurMethodDecl(); 2027 2028 // There are two cases to handle here. 1) scoped lookup could have failed, 2029 // in which case we should look for an ivar. 2) scoped lookup could have 2030 // found a decl, but that decl is outside the current instance method (i.e. 2031 // a global variable). In these two cases, we do a lookup for an ivar with 2032 // this name, if the lookup sucedes, we replace it our current decl. 2033 2034 // If we're in a class method, we don't normally want to look for 2035 // ivars. But if we don't find anything else, and there's an 2036 // ivar, that's an error. 2037 bool IsClassMethod = CurMethod->isClassMethod(); 2038 2039 bool LookForIvars; 2040 if (Lookup.empty()) 2041 LookForIvars = true; 2042 else if (IsClassMethod) 2043 LookForIvars = false; 2044 else 2045 LookForIvars = (Lookup.isSingleResult() && 2046 Lookup.getFoundDecl()->isDefinedOutsideFunctionOrMethod()); 2047 ObjCInterfaceDecl *IFace = 0; 2048 if (LookForIvars) { 2049 IFace = CurMethod->getClassInterface(); 2050 ObjCInterfaceDecl *ClassDeclared; 2051 if (ObjCIvarDecl *IV = IFace->lookupInstanceVariable(II, ClassDeclared)) { 2052 // Diagnose using an ivar in a class method. 2053 if (IsClassMethod) 2054 return ExprError(Diag(Loc, diag::error_ivar_use_in_class_method) 2055 << IV->getDeclName()); 2056 2057 // If we're referencing an invalid decl, just return this as a silent 2058 // error node. The error diagnostic was already emitted on the decl. 2059 if (IV->isInvalidDecl()) 2060 return ExprError(); 2061 2062 // Check if referencing a field with __attribute__((deprecated)). 2063 if (DiagnoseUseOfDecl(IV, Loc)) 2064 return ExprError(); 2065 2066 // Diagnose the use of an ivar outside of the declaring class. 2067 if (IV->getAccessControl() == ObjCIvarDecl::Private && 2068 ClassDeclared != IFace) 2069 Diag(Loc, diag::error_private_ivar_access) << IV->getDeclName(); 2070 2071 // FIXME: This should use a new expr for a direct reference, don't 2072 // turn this into Self->ivar, just return a BareIVarExpr or something. 2073 IdentifierInfo &II = Context.Idents.get("self"); 2074 UnqualifiedId SelfName; 2075 SelfName.setIdentifier(&II, SourceLocation()); 2076 CXXScopeSpec SelfScopeSpec; 2077 ExprResult SelfExpr = ActOnIdExpression(S, SelfScopeSpec, 2078 SelfName, false, false); 2079 if (SelfExpr.isInvalid()) 2080 return ExprError(); 2081 2082 SelfExpr = DefaultLvalueConversion(SelfExpr.take()); 2083 if (SelfExpr.isInvalid()) 2084 return ExprError(); 2085 2086 MarkDeclarationReferenced(Loc, IV); 2087 Expr *base = SelfExpr.take(); 2088 base = base->IgnoreParenImpCasts(); 2089 if (const DeclRefExpr *DE = dyn_cast<DeclRefExpr>(base)) { 2090 const NamedDecl *ND = DE->getDecl(); 2091 if (!isa<ImplicitParamDecl>(ND)) { 2092 // relax the rule such that it is allowed to have a shadow 'self' 2093 // where stand-alone ivar can be found in this 'self' object. 2094 // This is to match gcc's behavior. 2095 ObjCInterfaceDecl *selfIFace = 0; 2096 if (const ObjCObjectPointerType *OPT = 2097 base->getType()->getAsObjCInterfacePointerType()) 2098 selfIFace = OPT->getInterfaceDecl(); 2099 if (!selfIFace || 2100 !selfIFace->lookupInstanceVariable(IV->getIdentifier())) { 2101 Diag(Loc, diag::error_implicit_ivar_access) 2102 << IV->getDeclName(); 2103 Diag(ND->getLocation(), diag::note_declared_at); 2104 return ExprError(); 2105 } 2106 } 2107 } 2108 return Owned(new (Context) 2109 ObjCIvarRefExpr(IV, IV->getType(), Loc, 2110 SelfExpr.take(), true, true)); 2111 } 2112 } else if (CurMethod->isInstanceMethod()) { 2113 // We should warn if a local variable hides an ivar. 2114 ObjCInterfaceDecl *IFace = CurMethod->getClassInterface(); 2115 ObjCInterfaceDecl *ClassDeclared; 2116 if (ObjCIvarDecl *IV = IFace->lookupInstanceVariable(II, ClassDeclared)) { 2117 if (IV->getAccessControl() != ObjCIvarDecl::Private || 2118 IFace == ClassDeclared) 2119 Diag(Loc, diag::warn_ivar_use_hidden) << IV->getDeclName(); 2120 } 2121 } 2122 2123 if (Lookup.empty() && II && AllowBuiltinCreation) { 2124 // FIXME. Consolidate this with similar code in LookupName. 2125 if (unsigned BuiltinID = II->getBuiltinID()) { 2126 if (!(getLangOptions().CPlusPlus && 2127 Context.BuiltinInfo.isPredefinedLibFunction(BuiltinID))) { 2128 NamedDecl *D = LazilyCreateBuiltin((IdentifierInfo *)II, BuiltinID, 2129 S, Lookup.isForRedeclaration(), 2130 Lookup.getNameLoc()); 2131 if (D) Lookup.addDecl(D); 2132 } 2133 } 2134 } 2135 // Sentinel value saying that we didn't do anything special. 2136 return Owned((Expr*) 0); 2137} 2138 2139/// \brief Cast a base object to a member's actual type. 2140/// 2141/// Logically this happens in three phases: 2142/// 2143/// * First we cast from the base type to the naming class. 2144/// The naming class is the class into which we were looking 2145/// when we found the member; it's the qualifier type if a 2146/// qualifier was provided, and otherwise it's the base type. 2147/// 2148/// * Next we cast from the naming class to the declaring class. 2149/// If the member we found was brought into a class's scope by 2150/// a using declaration, this is that class; otherwise it's 2151/// the class declaring the member. 2152/// 2153/// * Finally we cast from the declaring class to the "true" 2154/// declaring class of the member. This conversion does not 2155/// obey access control. 2156ExprResult 2157Sema::PerformObjectMemberConversion(Expr *From, 2158 NestedNameSpecifier *Qualifier, 2159 NamedDecl *FoundDecl, 2160 NamedDecl *Member) { 2161 CXXRecordDecl *RD = dyn_cast<CXXRecordDecl>(Member->getDeclContext()); 2162 if (!RD) 2163 return Owned(From); 2164 2165 QualType DestRecordType; 2166 QualType DestType; 2167 QualType FromRecordType; 2168 QualType FromType = From->getType(); 2169 bool PointerConversions = false; 2170 if (isa<FieldDecl>(Member)) { 2171 DestRecordType = Context.getCanonicalType(Context.getTypeDeclType(RD)); 2172 2173 if (FromType->getAs<PointerType>()) { 2174 DestType = Context.getPointerType(DestRecordType); 2175 FromRecordType = FromType->getPointeeType(); 2176 PointerConversions = true; 2177 } else { 2178 DestType = DestRecordType; 2179 FromRecordType = FromType; 2180 } 2181 } else if (CXXMethodDecl *Method = dyn_cast<CXXMethodDecl>(Member)) { 2182 if (Method->isStatic()) 2183 return Owned(From); 2184 2185 DestType = Method->getThisType(Context); 2186 DestRecordType = DestType->getPointeeType(); 2187 2188 if (FromType->getAs<PointerType>()) { 2189 FromRecordType = FromType->getPointeeType(); 2190 PointerConversions = true; 2191 } else { 2192 FromRecordType = FromType; 2193 DestType = DestRecordType; 2194 } 2195 } else { 2196 // No conversion necessary. 2197 return Owned(From); 2198 } 2199 2200 if (DestType->isDependentType() || FromType->isDependentType()) 2201 return Owned(From); 2202 2203 // If the unqualified types are the same, no conversion is necessary. 2204 if (Context.hasSameUnqualifiedType(FromRecordType, DestRecordType)) 2205 return Owned(From); 2206 2207 SourceRange FromRange = From->getSourceRange(); 2208 SourceLocation FromLoc = FromRange.getBegin(); 2209 2210 ExprValueKind VK = CastCategory(From); 2211 2212 // C++ [class.member.lookup]p8: 2213 // [...] Ambiguities can often be resolved by qualifying a name with its 2214 // class name. 2215 // 2216 // If the member was a qualified name and the qualified referred to a 2217 // specific base subobject type, we'll cast to that intermediate type 2218 // first and then to the object in which the member is declared. That allows 2219 // one to resolve ambiguities in, e.g., a diamond-shaped hierarchy such as: 2220 // 2221 // class Base { public: int x; }; 2222 // class Derived1 : public Base { }; 2223 // class Derived2 : public Base { }; 2224 // class VeryDerived : public Derived1, public Derived2 { void f(); }; 2225 // 2226 // void VeryDerived::f() { 2227 // x = 17; // error: ambiguous base subobjects 2228 // Derived1::x = 17; // okay, pick the Base subobject of Derived1 2229 // } 2230 if (Qualifier) { 2231 QualType QType = QualType(Qualifier->getAsType(), 0); 2232 assert(!QType.isNull() && "lookup done with dependent qualifier?"); 2233 assert(QType->isRecordType() && "lookup done with non-record type"); 2234 2235 QualType QRecordType = QualType(QType->getAs<RecordType>(), 0); 2236 2237 // In C++98, the qualifier type doesn't actually have to be a base 2238 // type of the object type, in which case we just ignore it. 2239 // Otherwise build the appropriate casts. 2240 if (IsDerivedFrom(FromRecordType, QRecordType)) { 2241 CXXCastPath BasePath; 2242 if (CheckDerivedToBaseConversion(FromRecordType, QRecordType, 2243 FromLoc, FromRange, &BasePath)) 2244 return ExprError(); 2245 2246 if (PointerConversions) 2247 QType = Context.getPointerType(QType); 2248 From = ImpCastExprToType(From, QType, CK_UncheckedDerivedToBase, 2249 VK, &BasePath).take(); 2250 2251 FromType = QType; 2252 FromRecordType = QRecordType; 2253 2254 // If the qualifier type was the same as the destination type, 2255 // we're done. 2256 if (Context.hasSameUnqualifiedType(FromRecordType, DestRecordType)) 2257 return Owned(From); 2258 } 2259 } 2260 2261 bool IgnoreAccess = false; 2262 2263 // If we actually found the member through a using declaration, cast 2264 // down to the using declaration's type. 2265 // 2266 // Pointer equality is fine here because only one declaration of a 2267 // class ever has member declarations. 2268 if (FoundDecl->getDeclContext() != Member->getDeclContext()) { 2269 assert(isa<UsingShadowDecl>(FoundDecl)); 2270 QualType URecordType = Context.getTypeDeclType( 2271 cast<CXXRecordDecl>(FoundDecl->getDeclContext())); 2272 2273 // We only need to do this if the naming-class to declaring-class 2274 // conversion is non-trivial. 2275 if (!Context.hasSameUnqualifiedType(FromRecordType, URecordType)) { 2276 assert(IsDerivedFrom(FromRecordType, URecordType)); 2277 CXXCastPath BasePath; 2278 if (CheckDerivedToBaseConversion(FromRecordType, URecordType, 2279 FromLoc, FromRange, &BasePath)) 2280 return ExprError(); 2281 2282 QualType UType = URecordType; 2283 if (PointerConversions) 2284 UType = Context.getPointerType(UType); 2285 From = ImpCastExprToType(From, UType, CK_UncheckedDerivedToBase, 2286 VK, &BasePath).take(); 2287 FromType = UType; 2288 FromRecordType = URecordType; 2289 } 2290 2291 // We don't do access control for the conversion from the 2292 // declaring class to the true declaring class. 2293 IgnoreAccess = true; 2294 } 2295 2296 CXXCastPath BasePath; 2297 if (CheckDerivedToBaseConversion(FromRecordType, DestRecordType, 2298 FromLoc, FromRange, &BasePath, 2299 IgnoreAccess)) 2300 return ExprError(); 2301 2302 return ImpCastExprToType(From, DestType, CK_UncheckedDerivedToBase, 2303 VK, &BasePath); 2304} 2305 2306/// \brief Build a MemberExpr AST node. 2307static MemberExpr *BuildMemberExpr(ASTContext &C, Expr *Base, bool isArrow, 2308 const CXXScopeSpec &SS, ValueDecl *Member, 2309 DeclAccessPair FoundDecl, 2310 const DeclarationNameInfo &MemberNameInfo, 2311 QualType Ty, 2312 ExprValueKind VK, ExprObjectKind OK, 2313 const TemplateArgumentListInfo *TemplateArgs = 0) { 2314 return MemberExpr::Create(C, Base, isArrow, SS.getWithLocInContext(C), 2315 Member, FoundDecl, MemberNameInfo, 2316 TemplateArgs, Ty, VK, OK); 2317} 2318 2319static ExprResult 2320BuildFieldReferenceExpr(Sema &S, Expr *BaseExpr, bool IsArrow, 2321 const CXXScopeSpec &SS, FieldDecl *Field, 2322 DeclAccessPair FoundDecl, 2323 const DeclarationNameInfo &MemberNameInfo) { 2324 // x.a is an l-value if 'a' has a reference type. Otherwise: 2325 // x.a is an l-value/x-value/pr-value if the base is (and note 2326 // that *x is always an l-value), except that if the base isn't 2327 // an ordinary object then we must have an rvalue. 2328 ExprValueKind VK = VK_LValue; 2329 ExprObjectKind OK = OK_Ordinary; 2330 if (!IsArrow) { 2331 if (BaseExpr->getObjectKind() == OK_Ordinary) 2332 VK = BaseExpr->getValueKind(); 2333 else 2334 VK = VK_RValue; 2335 } 2336 if (VK != VK_RValue && Field->isBitField()) 2337 OK = OK_BitField; 2338 2339 // Figure out the type of the member; see C99 6.5.2.3p3, C++ [expr.ref] 2340 QualType MemberType = Field->getType(); 2341 if (const ReferenceType *Ref = MemberType->getAs<ReferenceType>()) { 2342 MemberType = Ref->getPointeeType(); 2343 VK = VK_LValue; 2344 } else { 2345 QualType BaseType = BaseExpr->getType(); 2346 if (IsArrow) BaseType = BaseType->getAs<PointerType>()->getPointeeType(); 2347 2348 Qualifiers BaseQuals = BaseType.getQualifiers(); 2349 2350 // GC attributes are never picked up by members. 2351 BaseQuals.removeObjCGCAttr(); 2352 2353 // CVR attributes from the base are picked up by members, 2354 // except that 'mutable' members don't pick up 'const'. 2355 if (Field->isMutable()) BaseQuals.removeConst(); 2356 2357 Qualifiers MemberQuals 2358 = S.Context.getCanonicalType(MemberType).getQualifiers(); 2359 2360 // TR 18037 does not allow fields to be declared with address spaces. 2361 assert(!MemberQuals.hasAddressSpace()); 2362 2363 Qualifiers Combined = BaseQuals + MemberQuals; 2364 if (Combined != MemberQuals) 2365 MemberType = S.Context.getQualifiedType(MemberType, Combined); 2366 } 2367 2368 S.MarkDeclarationReferenced(MemberNameInfo.getLoc(), Field); 2369 ExprResult Base = 2370 S.PerformObjectMemberConversion(BaseExpr, SS.getScopeRep(), 2371 FoundDecl, Field); 2372 if (Base.isInvalid()) 2373 return ExprError(); 2374 return S.Owned(BuildMemberExpr(S.Context, Base.take(), IsArrow, SS, 2375 Field, FoundDecl, MemberNameInfo, 2376 MemberType, VK, OK)); 2377} 2378 2379/// Builds an implicit member access expression. The current context 2380/// is known to be an instance method, and the given unqualified lookup 2381/// set is known to contain only instance members, at least one of which 2382/// is from an appropriate type. 2383ExprResult 2384Sema::BuildImplicitMemberExpr(const CXXScopeSpec &SS, 2385 LookupResult &R, 2386 const TemplateArgumentListInfo *TemplateArgs, 2387 bool IsKnownInstance) { 2388 assert(!R.empty() && !R.isAmbiguous()); 2389 2390 SourceLocation loc = R.getNameLoc(); 2391 2392 // We may have found a field within an anonymous union or struct 2393 // (C++ [class.union]). 2394 // FIXME: template-ids inside anonymous structs? 2395 if (IndirectFieldDecl *FD = R.getAsSingle<IndirectFieldDecl>()) 2396 return BuildAnonymousStructUnionMemberReference(SS, R.getNameLoc(), FD); 2397 2398 // If this is known to be an instance access, go ahead and build an 2399 // implicit 'this' expression now. 2400 // 'this' expression now. 2401 CXXMethodDecl *method = tryCaptureCXXThis(); 2402 assert(method && "didn't correctly pre-flight capture of 'this'"); 2403 2404 QualType thisType = method->getThisType(Context); 2405 Expr *baseExpr = 0; // null signifies implicit access 2406 if (IsKnownInstance) { 2407 SourceLocation Loc = R.getNameLoc(); 2408 if (SS.getRange().isValid()) 2409 Loc = SS.getRange().getBegin(); 2410 baseExpr = new (Context) CXXThisExpr(loc, thisType, /*isImplicit=*/true); 2411 } 2412 2413 return BuildMemberReferenceExpr(baseExpr, thisType, 2414 /*OpLoc*/ SourceLocation(), 2415 /*IsArrow*/ true, 2416 SS, 2417 /*FirstQualifierInScope*/ 0, 2418 R, TemplateArgs); 2419} 2420 2421bool Sema::UseArgumentDependentLookup(const CXXScopeSpec &SS, 2422 const LookupResult &R, 2423 bool HasTrailingLParen) { 2424 // Only when used directly as the postfix-expression of a call. 2425 if (!HasTrailingLParen) 2426 return false; 2427 2428 // Never if a scope specifier was provided. 2429 if (SS.isSet()) 2430 return false; 2431 2432 // Only in C++ or ObjC++. 2433 if (!getLangOptions().CPlusPlus) 2434 return false; 2435 2436 // Turn off ADL when we find certain kinds of declarations during 2437 // normal lookup: 2438 for (LookupResult::iterator I = R.begin(), E = R.end(); I != E; ++I) { 2439 NamedDecl *D = *I; 2440 2441 // C++0x [basic.lookup.argdep]p3: 2442 // -- a declaration of a class member 2443 // Since using decls preserve this property, we check this on the 2444 // original decl. 2445 if (D->isCXXClassMember()) 2446 return false; 2447 2448 // C++0x [basic.lookup.argdep]p3: 2449 // -- a block-scope function declaration that is not a 2450 // using-declaration 2451 // NOTE: we also trigger this for function templates (in fact, we 2452 // don't check the decl type at all, since all other decl types 2453 // turn off ADL anyway). 2454 if (isa<UsingShadowDecl>(D)) 2455 D = cast<UsingShadowDecl>(D)->getTargetDecl(); 2456 else if (D->getDeclContext()->isFunctionOrMethod()) 2457 return false; 2458 2459 // C++0x [basic.lookup.argdep]p3: 2460 // -- a declaration that is neither a function or a function 2461 // template 2462 // And also for builtin functions. 2463 if (isa<FunctionDecl>(D)) { 2464 FunctionDecl *FDecl = cast<FunctionDecl>(D); 2465 2466 // But also builtin functions. 2467 if (FDecl->getBuiltinID() && FDecl->isImplicit()) 2468 return false; 2469 } else if (!isa<FunctionTemplateDecl>(D)) 2470 return false; 2471 } 2472 2473 return true; 2474} 2475 2476 2477/// Diagnoses obvious problems with the use of the given declaration 2478/// as an expression. This is only actually called for lookups that 2479/// were not overloaded, and it doesn't promise that the declaration 2480/// will in fact be used. 2481static bool CheckDeclInExpr(Sema &S, SourceLocation Loc, NamedDecl *D) { 2482 if (isa<TypedefNameDecl>(D)) { 2483 S.Diag(Loc, diag::err_unexpected_typedef) << D->getDeclName(); 2484 return true; 2485 } 2486 2487 if (isa<ObjCInterfaceDecl>(D)) { 2488 S.Diag(Loc, diag::err_unexpected_interface) << D->getDeclName(); 2489 return true; 2490 } 2491 2492 if (isa<NamespaceDecl>(D)) { 2493 S.Diag(Loc, diag::err_unexpected_namespace) << D->getDeclName(); 2494 return true; 2495 } 2496 2497 return false; 2498} 2499 2500ExprResult 2501Sema::BuildDeclarationNameExpr(const CXXScopeSpec &SS, 2502 LookupResult &R, 2503 bool NeedsADL) { 2504 // If this is a single, fully-resolved result and we don't need ADL, 2505 // just build an ordinary singleton decl ref. 2506 if (!NeedsADL && R.isSingleResult() && !R.getAsSingle<FunctionTemplateDecl>()) 2507 return BuildDeclarationNameExpr(SS, R.getLookupNameInfo(), 2508 R.getFoundDecl()); 2509 2510 // We only need to check the declaration if there's exactly one 2511 // result, because in the overloaded case the results can only be 2512 // functions and function templates. 2513 if (R.isSingleResult() && 2514 CheckDeclInExpr(*this, R.getNameLoc(), R.getFoundDecl())) 2515 return ExprError(); 2516 2517 // Otherwise, just build an unresolved lookup expression. Suppress 2518 // any lookup-related diagnostics; we'll hash these out later, when 2519 // we've picked a target. 2520 R.suppressDiagnostics(); 2521 2522 UnresolvedLookupExpr *ULE 2523 = UnresolvedLookupExpr::Create(Context, R.getNamingClass(), 2524 SS.getWithLocInContext(Context), 2525 R.getLookupNameInfo(), 2526 NeedsADL, R.isOverloadedResult(), 2527 R.begin(), R.end()); 2528 2529 return Owned(ULE); 2530} 2531 2532/// \brief Complete semantic analysis for a reference to the given declaration. 2533ExprResult 2534Sema::BuildDeclarationNameExpr(const CXXScopeSpec &SS, 2535 const DeclarationNameInfo &NameInfo, 2536 NamedDecl *D) { 2537 assert(D && "Cannot refer to a NULL declaration"); 2538 assert(!isa<FunctionTemplateDecl>(D) && 2539 "Cannot refer unambiguously to a function template"); 2540 2541 SourceLocation Loc = NameInfo.getLoc(); 2542 if (CheckDeclInExpr(*this, Loc, D)) 2543 return ExprError(); 2544 2545 if (TemplateDecl *Template = dyn_cast<TemplateDecl>(D)) { 2546 // Specifically diagnose references to class templates that are missing 2547 // a template argument list. 2548 Diag(Loc, diag::err_template_decl_ref) 2549 << Template << SS.getRange(); 2550 Diag(Template->getLocation(), diag::note_template_decl_here); 2551 return ExprError(); 2552 } 2553 2554 // Make sure that we're referring to a value. 2555 ValueDecl *VD = dyn_cast<ValueDecl>(D); 2556 if (!VD) { 2557 Diag(Loc, diag::err_ref_non_value) 2558 << D << SS.getRange(); 2559 Diag(D->getLocation(), diag::note_declared_at); 2560 return ExprError(); 2561 } 2562 2563 // Check whether this declaration can be used. Note that we suppress 2564 // this check when we're going to perform argument-dependent lookup 2565 // on this function name, because this might not be the function 2566 // that overload resolution actually selects. 2567 if (DiagnoseUseOfDecl(VD, Loc)) 2568 return ExprError(); 2569 2570 // Only create DeclRefExpr's for valid Decl's. 2571 if (VD->isInvalidDecl()) 2572 return ExprError(); 2573 2574 // Handle members of anonymous structs and unions. If we got here, 2575 // and the reference is to a class member indirect field, then this 2576 // must be the subject of a pointer-to-member expression. 2577 if (IndirectFieldDecl *indirectField = dyn_cast<IndirectFieldDecl>(VD)) 2578 if (!indirectField->isCXXClassMember()) 2579 return BuildAnonymousStructUnionMemberReference(SS, NameInfo.getLoc(), 2580 indirectField); 2581 2582 // If the identifier reference is inside a block, and it refers to a value 2583 // that is outside the block, create a BlockDeclRefExpr instead of a 2584 // DeclRefExpr. This ensures the value is treated as a copy-in snapshot when 2585 // the block is formed. 2586 // 2587 // We do not do this for things like enum constants, global variables, etc, 2588 // as they do not get snapshotted. 2589 // 2590 switch (shouldCaptureValueReference(*this, NameInfo.getLoc(), VD)) { 2591 case CR_Error: 2592 return ExprError(); 2593 2594 case CR_Capture: 2595 assert(!SS.isSet() && "referenced local variable with scope specifier?"); 2596 return BuildBlockDeclRefExpr(*this, VD, NameInfo, /*byref*/ false); 2597 2598 case CR_CaptureByRef: 2599 assert(!SS.isSet() && "referenced local variable with scope specifier?"); 2600 return BuildBlockDeclRefExpr(*this, VD, NameInfo, /*byref*/ true); 2601 2602 case CR_NoCapture: { 2603 // If this reference is not in a block or if the referenced 2604 // variable is within the block, create a normal DeclRefExpr. 2605 2606 QualType type = VD->getType(); 2607 ExprValueKind valueKind = VK_RValue; 2608 2609 switch (D->getKind()) { 2610 // Ignore all the non-ValueDecl kinds. 2611#define ABSTRACT_DECL(kind) 2612#define VALUE(type, base) 2613#define DECL(type, base) \ 2614 case Decl::type: 2615#include "clang/AST/DeclNodes.inc" 2616 llvm_unreachable("invalid value decl kind"); 2617 return ExprError(); 2618 2619 // These shouldn't make it here. 2620 case Decl::ObjCAtDefsField: 2621 case Decl::ObjCIvar: 2622 llvm_unreachable("forming non-member reference to ivar?"); 2623 return ExprError(); 2624 2625 // Enum constants are always r-values and never references. 2626 // Unresolved using declarations are dependent. 2627 case Decl::EnumConstant: 2628 case Decl::UnresolvedUsingValue: 2629 valueKind = VK_RValue; 2630 break; 2631 2632 // Fields and indirect fields that got here must be for 2633 // pointer-to-member expressions; we just call them l-values for 2634 // internal consistency, because this subexpression doesn't really 2635 // exist in the high-level semantics. 2636 case Decl::Field: 2637 case Decl::IndirectField: 2638 assert(getLangOptions().CPlusPlus && 2639 "building reference to field in C?"); 2640 2641 // These can't have reference type in well-formed programs, but 2642 // for internal consistency we do this anyway. 2643 type = type.getNonReferenceType(); 2644 valueKind = VK_LValue; 2645 break; 2646 2647 // Non-type template parameters are either l-values or r-values 2648 // depending on the type. 2649 case Decl::NonTypeTemplateParm: { 2650 if (const ReferenceType *reftype = type->getAs<ReferenceType>()) { 2651 type = reftype->getPointeeType(); 2652 valueKind = VK_LValue; // even if the parameter is an r-value reference 2653 break; 2654 } 2655 2656 // For non-references, we need to strip qualifiers just in case 2657 // the template parameter was declared as 'const int' or whatever. 2658 valueKind = VK_RValue; 2659 type = type.getUnqualifiedType(); 2660 break; 2661 } 2662 2663 case Decl::Var: 2664 // In C, "extern void blah;" is valid and is an r-value. 2665 if (!getLangOptions().CPlusPlus && 2666 !type.hasQualifiers() && 2667 type->isVoidType()) { 2668 valueKind = VK_RValue; 2669 break; 2670 } 2671 // fallthrough 2672 2673 case Decl::ImplicitParam: 2674 case Decl::ParmVar: 2675 // These are always l-values. 2676 valueKind = VK_LValue; 2677 type = type.getNonReferenceType(); 2678 break; 2679 2680 case Decl::Function: { 2681 const FunctionType *fty = type->castAs<FunctionType>(); 2682 2683 // If we're referring to a function with an __unknown_anytype 2684 // result type, make the entire expression __unknown_anytype. 2685 if (fty->getResultType() == Context.UnknownAnyTy) { 2686 type = Context.UnknownAnyTy; 2687 valueKind = VK_RValue; 2688 break; 2689 } 2690 2691 // Functions are l-values in C++. 2692 if (getLangOptions().CPlusPlus) { 2693 valueKind = VK_LValue; 2694 break; 2695 } 2696 2697 // C99 DR 316 says that, if a function type comes from a 2698 // function definition (without a prototype), that type is only 2699 // used for checking compatibility. Therefore, when referencing 2700 // the function, we pretend that we don't have the full function 2701 // type. 2702 if (!cast<FunctionDecl>(VD)->hasPrototype() && 2703 isa<FunctionProtoType>(fty)) 2704 type = Context.getFunctionNoProtoType(fty->getResultType(), 2705 fty->getExtInfo()); 2706 2707 // Functions are r-values in C. 2708 valueKind = VK_RValue; 2709 break; 2710 } 2711 2712 case Decl::CXXMethod: 2713 // If we're referring to a method with an __unknown_anytype 2714 // result type, make the entire expression __unknown_anytype. 2715 // This should only be possible with a type written directly. 2716 if (const FunctionProtoType *proto = dyn_cast<FunctionProtoType>(VD->getType())) 2717 if (proto->getResultType() == Context.UnknownAnyTy) { 2718 type = Context.UnknownAnyTy; 2719 valueKind = VK_RValue; 2720 break; 2721 } 2722 2723 // C++ methods are l-values if static, r-values if non-static. 2724 if (cast<CXXMethodDecl>(VD)->isStatic()) { 2725 valueKind = VK_LValue; 2726 break; 2727 } 2728 // fallthrough 2729 2730 case Decl::CXXConversion: 2731 case Decl::CXXDestructor: 2732 case Decl::CXXConstructor: 2733 valueKind = VK_RValue; 2734 break; 2735 } 2736 2737 return BuildDeclRefExpr(VD, type, valueKind, NameInfo, &SS); 2738 } 2739 2740 } 2741 2742 llvm_unreachable("unknown capture result"); 2743 return ExprError(); 2744} 2745 2746ExprResult Sema::ActOnPredefinedExpr(SourceLocation Loc, tok::TokenKind Kind) { 2747 PredefinedExpr::IdentType IT; 2748 2749 switch (Kind) { 2750 default: assert(0 && "Unknown simple primary expr!"); 2751 case tok::kw___func__: IT = PredefinedExpr::Func; break; // [C99 6.4.2.2] 2752 case tok::kw___FUNCTION__: IT = PredefinedExpr::Function; break; 2753 case tok::kw___PRETTY_FUNCTION__: IT = PredefinedExpr::PrettyFunction; break; 2754 } 2755 2756 // Pre-defined identifiers are of type char[x], where x is the length of the 2757 // string. 2758 2759 Decl *currentDecl = getCurFunctionOrMethodDecl(); 2760 if (!currentDecl && getCurBlock()) 2761 currentDecl = getCurBlock()->TheDecl; 2762 if (!currentDecl) { 2763 Diag(Loc, diag::ext_predef_outside_function); 2764 currentDecl = Context.getTranslationUnitDecl(); 2765 } 2766 2767 QualType ResTy; 2768 if (cast<DeclContext>(currentDecl)->isDependentContext()) { 2769 ResTy = Context.DependentTy; 2770 } else { 2771 unsigned Length = PredefinedExpr::ComputeName(IT, currentDecl).length(); 2772 2773 llvm::APInt LengthI(32, Length + 1); 2774 ResTy = Context.CharTy.withConst(); 2775 ResTy = Context.getConstantArrayType(ResTy, LengthI, ArrayType::Normal, 0); 2776 } 2777 return Owned(new (Context) PredefinedExpr(Loc, ResTy, IT)); 2778} 2779 2780ExprResult Sema::ActOnCharacterConstant(const Token &Tok) { 2781 llvm::SmallString<16> CharBuffer; 2782 bool Invalid = false; 2783 llvm::StringRef ThisTok = PP.getSpelling(Tok, CharBuffer, &Invalid); 2784 if (Invalid) 2785 return ExprError(); 2786 2787 CharLiteralParser Literal(ThisTok.begin(), ThisTok.end(), Tok.getLocation(), 2788 PP); 2789 if (Literal.hadError()) 2790 return ExprError(); 2791 2792 QualType Ty; 2793 if (!getLangOptions().CPlusPlus) 2794 Ty = Context.IntTy; // 'x' and L'x' -> int in C. 2795 else if (Literal.isWide()) 2796 Ty = Context.WCharTy; // L'x' -> wchar_t in C++. 2797 else if (Literal.isMultiChar()) 2798 Ty = Context.IntTy; // 'wxyz' -> int in C++. 2799 else 2800 Ty = Context.CharTy; // 'x' -> char in C++ 2801 2802 return Owned(new (Context) CharacterLiteral(Literal.getValue(), 2803 Literal.isWide(), 2804 Ty, Tok.getLocation())); 2805} 2806 2807ExprResult Sema::ActOnNumericConstant(const Token &Tok) { 2808 // Fast path for a single digit (which is quite common). A single digit 2809 // cannot have a trigraph, escaped newline, radix prefix, or type suffix. 2810 if (Tok.getLength() == 1) { 2811 const char Val = PP.getSpellingOfSingleCharacterNumericConstant(Tok); 2812 unsigned IntSize = Context.Target.getIntWidth(); 2813 return Owned(IntegerLiteral::Create(Context, llvm::APInt(IntSize, Val-'0'), 2814 Context.IntTy, Tok.getLocation())); 2815 } 2816 2817 llvm::SmallString<512> IntegerBuffer; 2818 // Add padding so that NumericLiteralParser can overread by one character. 2819 IntegerBuffer.resize(Tok.getLength()+1); 2820 const char *ThisTokBegin = &IntegerBuffer[0]; 2821 2822 // Get the spelling of the token, which eliminates trigraphs, etc. 2823 bool Invalid = false; 2824 unsigned ActualLength = PP.getSpelling(Tok, ThisTokBegin, &Invalid); 2825 if (Invalid) 2826 return ExprError(); 2827 2828 NumericLiteralParser Literal(ThisTokBegin, ThisTokBegin+ActualLength, 2829 Tok.getLocation(), PP); 2830 if (Literal.hadError) 2831 return ExprError(); 2832 2833 Expr *Res; 2834 2835 if (Literal.isFloatingLiteral()) { 2836 QualType Ty; 2837 if (Literal.isFloat) 2838 Ty = Context.FloatTy; 2839 else if (!Literal.isLong) 2840 Ty = Context.DoubleTy; 2841 else 2842 Ty = Context.LongDoubleTy; 2843 2844 const llvm::fltSemantics &Format = Context.getFloatTypeSemantics(Ty); 2845 2846 using llvm::APFloat; 2847 APFloat Val(Format); 2848 2849 APFloat::opStatus result = Literal.GetFloatValue(Val); 2850 2851 // Overflow is always an error, but underflow is only an error if 2852 // we underflowed to zero (APFloat reports denormals as underflow). 2853 if ((result & APFloat::opOverflow) || 2854 ((result & APFloat::opUnderflow) && Val.isZero())) { 2855 unsigned diagnostic; 2856 llvm::SmallString<20> buffer; 2857 if (result & APFloat::opOverflow) { 2858 diagnostic = diag::warn_float_overflow; 2859 APFloat::getLargest(Format).toString(buffer); 2860 } else { 2861 diagnostic = diag::warn_float_underflow; 2862 APFloat::getSmallest(Format).toString(buffer); 2863 } 2864 2865 Diag(Tok.getLocation(), diagnostic) 2866 << Ty 2867 << llvm::StringRef(buffer.data(), buffer.size()); 2868 } 2869 2870 bool isExact = (result == APFloat::opOK); 2871 Res = FloatingLiteral::Create(Context, Val, isExact, Ty, Tok.getLocation()); 2872 2873 if (Ty == Context.DoubleTy) { 2874 if (getLangOptions().SinglePrecisionConstants) { 2875 Res = ImpCastExprToType(Res, Context.FloatTy, CK_FloatingCast).take(); 2876 } else if (getLangOptions().OpenCL && !getOpenCLOptions().cl_khr_fp64) { 2877 Diag(Tok.getLocation(), diag::warn_double_const_requires_fp64); 2878 Res = ImpCastExprToType(Res, Context.FloatTy, CK_FloatingCast).take(); 2879 } 2880 } 2881 } else if (!Literal.isIntegerLiteral()) { 2882 return ExprError(); 2883 } else { 2884 QualType Ty; 2885 2886 // long long is a C99 feature. 2887 if (!getLangOptions().C99 && !getLangOptions().CPlusPlus0x && 2888 Literal.isLongLong) 2889 Diag(Tok.getLocation(), diag::ext_longlong); 2890 2891 // Get the value in the widest-possible width. 2892 llvm::APInt ResultVal(Context.Target.getIntMaxTWidth(), 0); 2893 2894 if (Literal.GetIntegerValue(ResultVal)) { 2895 // If this value didn't fit into uintmax_t, warn and force to ull. 2896 Diag(Tok.getLocation(), diag::warn_integer_too_large); 2897 Ty = Context.UnsignedLongLongTy; 2898 assert(Context.getTypeSize(Ty) == ResultVal.getBitWidth() && 2899 "long long is not intmax_t?"); 2900 } else { 2901 // If this value fits into a ULL, try to figure out what else it fits into 2902 // according to the rules of C99 6.4.4.1p5. 2903 2904 // Octal, Hexadecimal, and integers with a U suffix are allowed to 2905 // be an unsigned int. 2906 bool AllowUnsigned = Literal.isUnsigned || Literal.getRadix() != 10; 2907 2908 // Check from smallest to largest, picking the smallest type we can. 2909 unsigned Width = 0; 2910 if (!Literal.isLong && !Literal.isLongLong) { 2911 // Are int/unsigned possibilities? 2912 unsigned IntSize = Context.Target.getIntWidth(); 2913 2914 // Does it fit in a unsigned int? 2915 if (ResultVal.isIntN(IntSize)) { 2916 // Does it fit in a signed int? 2917 if (!Literal.isUnsigned && ResultVal[IntSize-1] == 0) 2918 Ty = Context.IntTy; 2919 else if (AllowUnsigned) 2920 Ty = Context.UnsignedIntTy; 2921 Width = IntSize; 2922 } 2923 } 2924 2925 // Are long/unsigned long possibilities? 2926 if (Ty.isNull() && !Literal.isLongLong) { 2927 unsigned LongSize = Context.Target.getLongWidth(); 2928 2929 // Does it fit in a unsigned long? 2930 if (ResultVal.isIntN(LongSize)) { 2931 // Does it fit in a signed long? 2932 if (!Literal.isUnsigned && ResultVal[LongSize-1] == 0) 2933 Ty = Context.LongTy; 2934 else if (AllowUnsigned) 2935 Ty = Context.UnsignedLongTy; 2936 Width = LongSize; 2937 } 2938 } 2939 2940 // Finally, check long long if needed. 2941 if (Ty.isNull()) { 2942 unsigned LongLongSize = Context.Target.getLongLongWidth(); 2943 2944 // Does it fit in a unsigned long long? 2945 if (ResultVal.isIntN(LongLongSize)) { 2946 // Does it fit in a signed long long? 2947 // To be compatible with MSVC, hex integer literals ending with the 2948 // LL or i64 suffix are always signed in Microsoft mode. 2949 if (!Literal.isUnsigned && (ResultVal[LongLongSize-1] == 0 || 2950 (getLangOptions().Microsoft && Literal.isLongLong))) 2951 Ty = Context.LongLongTy; 2952 else if (AllowUnsigned) 2953 Ty = Context.UnsignedLongLongTy; 2954 Width = LongLongSize; 2955 } 2956 } 2957 2958 // If we still couldn't decide a type, we probably have something that 2959 // does not fit in a signed long long, but has no U suffix. 2960 if (Ty.isNull()) { 2961 Diag(Tok.getLocation(), diag::warn_integer_too_large_for_signed); 2962 Ty = Context.UnsignedLongLongTy; 2963 Width = Context.Target.getLongLongWidth(); 2964 } 2965 2966 if (ResultVal.getBitWidth() != Width) 2967 ResultVal = ResultVal.trunc(Width); 2968 } 2969 Res = IntegerLiteral::Create(Context, ResultVal, Ty, Tok.getLocation()); 2970 } 2971 2972 // If this is an imaginary literal, create the ImaginaryLiteral wrapper. 2973 if (Literal.isImaginary) 2974 Res = new (Context) ImaginaryLiteral(Res, 2975 Context.getComplexType(Res->getType())); 2976 2977 return Owned(Res); 2978} 2979 2980ExprResult Sema::ActOnParenExpr(SourceLocation L, 2981 SourceLocation R, Expr *E) { 2982 assert((E != 0) && "ActOnParenExpr() missing expr"); 2983 return Owned(new (Context) ParenExpr(L, R, E)); 2984} 2985 2986/// The UsualUnaryConversions() function is *not* called by this routine. 2987/// See C99 6.3.2.1p[2-4] for more details. 2988bool Sema::CheckUnaryExprOrTypeTraitOperand(QualType exprType, 2989 SourceLocation OpLoc, 2990 SourceRange ExprRange, 2991 UnaryExprOrTypeTrait ExprKind) { 2992 if (exprType->isDependentType()) 2993 return false; 2994 2995 // C++ [expr.sizeof]p2: "When applied to a reference or a reference type, 2996 // the result is the size of the referenced type." 2997 // C++ [expr.alignof]p3: "When alignof is applied to a reference type, the 2998 // result shall be the alignment of the referenced type." 2999 if (const ReferenceType *Ref = exprType->getAs<ReferenceType>()) 3000 exprType = Ref->getPointeeType(); 3001 3002 // [OpenCL 1.1 6.11.12] "The vec_step built-in function takes a built-in 3003 // scalar or vector data type argument..." 3004 // Every built-in scalar type (OpenCL 1.1 6.1.1) is either an arithmetic 3005 // type (C99 6.2.5p18) or void. 3006 if (ExprKind == UETT_VecStep) { 3007 if (!(exprType->isArithmeticType() || exprType->isVoidType() || 3008 exprType->isVectorType())) { 3009 Diag(OpLoc, diag::err_vecstep_non_scalar_vector_type) 3010 << exprType << ExprRange; 3011 return true; 3012 } 3013 } 3014 3015 // C99 6.5.3.4p1: 3016 if (exprType->isFunctionType()) { 3017 // alignof(function) is allowed as an extension. 3018 if (ExprKind == UETT_SizeOf) 3019 Diag(OpLoc, diag::ext_sizeof_function_type) 3020 << ExprRange; 3021 return false; 3022 } 3023 3024 // Allow sizeof(void)/alignof(void) as an extension. vec_step(void) is not 3025 // an extension, as void is a built-in scalar type (OpenCL 1.1 6.1.1). 3026 if (exprType->isVoidType()) { 3027 if (ExprKind != UETT_VecStep) 3028 Diag(OpLoc, diag::ext_sizeof_void_type) 3029 << ExprKind << ExprRange; 3030 return false; 3031 } 3032 3033 if (RequireCompleteType(OpLoc, exprType, 3034 PDiag(diag::err_sizeof_alignof_incomplete_type) 3035 << ExprKind << ExprRange)) 3036 return true; 3037 3038 // Reject sizeof(interface) and sizeof(interface<proto>) in 64-bit mode. 3039 if (LangOpts.ObjCNonFragileABI && exprType->isObjCObjectType()) { 3040 Diag(OpLoc, diag::err_sizeof_nonfragile_interface) 3041 << exprType << (ExprKind == UETT_SizeOf) 3042 << ExprRange; 3043 return true; 3044 } 3045 3046 return false; 3047} 3048 3049static bool CheckAlignOfExpr(Sema &S, Expr *E, SourceLocation OpLoc, 3050 SourceRange ExprRange) { 3051 E = E->IgnoreParens(); 3052 3053 // alignof decl is always ok. 3054 if (isa<DeclRefExpr>(E)) 3055 return false; 3056 3057 // Cannot know anything else if the expression is dependent. 3058 if (E->isTypeDependent()) 3059 return false; 3060 3061 if (E->getBitField()) { 3062 S. Diag(OpLoc, diag::err_sizeof_alignof_bitfield) << 1 << ExprRange; 3063 return true; 3064 } 3065 3066 // Alignment of a field access is always okay, so long as it isn't a 3067 // bit-field. 3068 if (MemberExpr *ME = dyn_cast<MemberExpr>(E)) 3069 if (isa<FieldDecl>(ME->getMemberDecl())) 3070 return false; 3071 3072 return S.CheckUnaryExprOrTypeTraitOperand(E->getType(), OpLoc, ExprRange, 3073 UETT_AlignOf); 3074} 3075 3076bool Sema::CheckVecStepExpr(Expr *E, SourceLocation OpLoc, 3077 SourceRange ExprRange) { 3078 E = E->IgnoreParens(); 3079 3080 // Cannot know anything else if the expression is dependent. 3081 if (E->isTypeDependent()) 3082 return false; 3083 3084 return CheckUnaryExprOrTypeTraitOperand(E->getType(), OpLoc, ExprRange, 3085 UETT_VecStep); 3086} 3087 3088/// \brief Build a sizeof or alignof expression given a type operand. 3089ExprResult 3090Sema::CreateUnaryExprOrTypeTraitExpr(TypeSourceInfo *TInfo, 3091 SourceLocation OpLoc, 3092 UnaryExprOrTypeTrait ExprKind, 3093 SourceRange R) { 3094 if (!TInfo) 3095 return ExprError(); 3096 3097 QualType T = TInfo->getType(); 3098 3099 if (!T->isDependentType() && 3100 CheckUnaryExprOrTypeTraitOperand(T, OpLoc, R, ExprKind)) 3101 return ExprError(); 3102 3103 // C99 6.5.3.4p4: the type (an unsigned integer type) is size_t. 3104 return Owned(new (Context) UnaryExprOrTypeTraitExpr(ExprKind, TInfo, 3105 Context.getSizeType(), 3106 OpLoc, R.getEnd())); 3107} 3108 3109/// \brief Build a sizeof or alignof expression given an expression 3110/// operand. 3111ExprResult 3112Sema::CreateUnaryExprOrTypeTraitExpr(Expr *E, SourceLocation OpLoc, 3113 UnaryExprOrTypeTrait ExprKind, 3114 SourceRange R) { 3115 // Verify that the operand is valid. 3116 bool isInvalid = false; 3117 if (E->isTypeDependent()) { 3118 // Delay type-checking for type-dependent expressions. 3119 } else if (ExprKind == UETT_AlignOf) { 3120 isInvalid = CheckAlignOfExpr(*this, E, OpLoc, R); 3121 } else if (ExprKind == UETT_VecStep) { 3122 isInvalid = CheckVecStepExpr(E, OpLoc, R); 3123 } else if (E->getBitField()) { // C99 6.5.3.4p1. 3124 Diag(OpLoc, diag::err_sizeof_alignof_bitfield) << 0; 3125 isInvalid = true; 3126 } else if (E->getType()->isPlaceholderType()) { 3127 ExprResult PE = CheckPlaceholderExpr(E); 3128 if (PE.isInvalid()) return ExprError(); 3129 return CreateUnaryExprOrTypeTraitExpr(PE.take(), OpLoc, ExprKind, R); 3130 } else { 3131 isInvalid = CheckUnaryExprOrTypeTraitOperand(E->getType(), OpLoc, R, 3132 UETT_SizeOf); 3133 } 3134 3135 if (isInvalid) 3136 return ExprError(); 3137 3138 // C99 6.5.3.4p4: the type (an unsigned integer type) is size_t. 3139 return Owned(new (Context) UnaryExprOrTypeTraitExpr(ExprKind, E, 3140 Context.getSizeType(), 3141 OpLoc, R.getEnd())); 3142} 3143 3144/// ActOnUnaryExprOrTypeTraitExpr - Handle @c sizeof(type) and @c sizeof @c 3145/// expr and the same for @c alignof and @c __alignof 3146/// Note that the ArgRange is invalid if isType is false. 3147ExprResult 3148Sema::ActOnUnaryExprOrTypeTraitExpr(SourceLocation OpLoc, 3149 UnaryExprOrTypeTrait ExprKind, bool isType, 3150 void *TyOrEx, const SourceRange &ArgRange) { 3151 // If error parsing type, ignore. 3152 if (TyOrEx == 0) return ExprError(); 3153 3154 if (isType) { 3155 TypeSourceInfo *TInfo; 3156 (void) GetTypeFromParser(ParsedType::getFromOpaquePtr(TyOrEx), &TInfo); 3157 return CreateUnaryExprOrTypeTraitExpr(TInfo, OpLoc, ExprKind, ArgRange); 3158 } 3159 3160 Expr *ArgEx = (Expr *)TyOrEx; 3161 ExprResult Result 3162 = CreateUnaryExprOrTypeTraitExpr(ArgEx, OpLoc, ExprKind, 3163 ArgEx->getSourceRange()); 3164 3165 return move(Result); 3166} 3167 3168static QualType CheckRealImagOperand(Sema &S, ExprResult &V, SourceLocation Loc, 3169 bool isReal) { 3170 if (V.get()->isTypeDependent()) 3171 return S.Context.DependentTy; 3172 3173 // _Real and _Imag are only l-values for normal l-values. 3174 if (V.get()->getObjectKind() != OK_Ordinary) { 3175 V = S.DefaultLvalueConversion(V.take()); 3176 if (V.isInvalid()) 3177 return QualType(); 3178 } 3179 3180 // These operators return the element type of a complex type. 3181 if (const ComplexType *CT = V.get()->getType()->getAs<ComplexType>()) 3182 return CT->getElementType(); 3183 3184 // Otherwise they pass through real integer and floating point types here. 3185 if (V.get()->getType()->isArithmeticType()) 3186 return V.get()->getType(); 3187 3188 // Test for placeholders. 3189 ExprResult PR = S.CheckPlaceholderExpr(V.get()); 3190 if (PR.isInvalid()) return QualType(); 3191 if (PR.get() != V.get()) { 3192 V = move(PR); 3193 return CheckRealImagOperand(S, V, Loc, isReal); 3194 } 3195 3196 // Reject anything else. 3197 S.Diag(Loc, diag::err_realimag_invalid_type) << V.get()->getType() 3198 << (isReal ? "__real" : "__imag"); 3199 return QualType(); 3200} 3201 3202 3203 3204ExprResult 3205Sema::ActOnPostfixUnaryOp(Scope *S, SourceLocation OpLoc, 3206 tok::TokenKind Kind, Expr *Input) { 3207 UnaryOperatorKind Opc; 3208 switch (Kind) { 3209 default: assert(0 && "Unknown unary op!"); 3210 case tok::plusplus: Opc = UO_PostInc; break; 3211 case tok::minusminus: Opc = UO_PostDec; break; 3212 } 3213 3214 return BuildUnaryOp(S, OpLoc, Opc, Input); 3215} 3216 3217/// Expressions of certain arbitrary types are forbidden by C from 3218/// having l-value type. These are: 3219/// - 'void', but not qualified void 3220/// - function types 3221/// 3222/// The exact rule here is C99 6.3.2.1: 3223/// An lvalue is an expression with an object type or an incomplete 3224/// type other than void. 3225static bool IsCForbiddenLValueType(ASTContext &C, QualType T) { 3226 return ((T->isVoidType() && !T.hasQualifiers()) || 3227 T->isFunctionType()); 3228} 3229 3230ExprResult 3231Sema::ActOnArraySubscriptExpr(Scope *S, Expr *Base, SourceLocation LLoc, 3232 Expr *Idx, SourceLocation RLoc) { 3233 // Since this might be a postfix expression, get rid of ParenListExprs. 3234 ExprResult Result = MaybeConvertParenListExprToParenExpr(S, Base); 3235 if (Result.isInvalid()) return ExprError(); 3236 Base = Result.take(); 3237 3238 Expr *LHSExp = Base, *RHSExp = Idx; 3239 3240 if (getLangOptions().CPlusPlus && 3241 (LHSExp->isTypeDependent() || RHSExp->isTypeDependent())) { 3242 return Owned(new (Context) ArraySubscriptExpr(LHSExp, RHSExp, 3243 Context.DependentTy, 3244 VK_LValue, OK_Ordinary, 3245 RLoc)); 3246 } 3247 3248 if (getLangOptions().CPlusPlus && 3249 (LHSExp->getType()->isRecordType() || 3250 LHSExp->getType()->isEnumeralType() || 3251 RHSExp->getType()->isRecordType() || 3252 RHSExp->getType()->isEnumeralType())) { 3253 return CreateOverloadedArraySubscriptExpr(LLoc, RLoc, Base, Idx); 3254 } 3255 3256 return CreateBuiltinArraySubscriptExpr(Base, LLoc, Idx, RLoc); 3257} 3258 3259 3260ExprResult 3261Sema::CreateBuiltinArraySubscriptExpr(Expr *Base, SourceLocation LLoc, 3262 Expr *Idx, SourceLocation RLoc) { 3263 Expr *LHSExp = Base; 3264 Expr *RHSExp = Idx; 3265 3266 // Perform default conversions. 3267 if (!LHSExp->getType()->getAs<VectorType>()) { 3268 ExprResult Result = DefaultFunctionArrayLvalueConversion(LHSExp); 3269 if (Result.isInvalid()) 3270 return ExprError(); 3271 LHSExp = Result.take(); 3272 } 3273 ExprResult Result = DefaultFunctionArrayLvalueConversion(RHSExp); 3274 if (Result.isInvalid()) 3275 return ExprError(); 3276 RHSExp = Result.take(); 3277 3278 QualType LHSTy = LHSExp->getType(), RHSTy = RHSExp->getType(); 3279 ExprValueKind VK = VK_LValue; 3280 ExprObjectKind OK = OK_Ordinary; 3281 3282 // C99 6.5.2.1p2: the expression e1[e2] is by definition precisely equivalent 3283 // to the expression *((e1)+(e2)). This means the array "Base" may actually be 3284 // in the subscript position. As a result, we need to derive the array base 3285 // and index from the expression types. 3286 Expr *BaseExpr, *IndexExpr; 3287 QualType ResultType; 3288 if (LHSTy->isDependentType() || RHSTy->isDependentType()) { 3289 BaseExpr = LHSExp; 3290 IndexExpr = RHSExp; 3291 ResultType = Context.DependentTy; 3292 } else if (const PointerType *PTy = LHSTy->getAs<PointerType>()) { 3293 BaseExpr = LHSExp; 3294 IndexExpr = RHSExp; 3295 ResultType = PTy->getPointeeType(); 3296 } else if (const PointerType *PTy = RHSTy->getAs<PointerType>()) { 3297 // Handle the uncommon case of "123[Ptr]". 3298 BaseExpr = RHSExp; 3299 IndexExpr = LHSExp; 3300 ResultType = PTy->getPointeeType(); 3301 } else if (const ObjCObjectPointerType *PTy = 3302 LHSTy->getAs<ObjCObjectPointerType>()) { 3303 BaseExpr = LHSExp; 3304 IndexExpr = RHSExp; 3305 ResultType = PTy->getPointeeType(); 3306 } else if (const ObjCObjectPointerType *PTy = 3307 RHSTy->getAs<ObjCObjectPointerType>()) { 3308 // Handle the uncommon case of "123[Ptr]". 3309 BaseExpr = RHSExp; 3310 IndexExpr = LHSExp; 3311 ResultType = PTy->getPointeeType(); 3312 } else if (const VectorType *VTy = LHSTy->getAs<VectorType>()) { 3313 BaseExpr = LHSExp; // vectors: V[123] 3314 IndexExpr = RHSExp; 3315 VK = LHSExp->getValueKind(); 3316 if (VK != VK_RValue) 3317 OK = OK_VectorComponent; 3318 3319 // FIXME: need to deal with const... 3320 ResultType = VTy->getElementType(); 3321 } else if (LHSTy->isArrayType()) { 3322 // If we see an array that wasn't promoted by 3323 // DefaultFunctionArrayLvalueConversion, it must be an array that 3324 // wasn't promoted because of the C90 rule that doesn't 3325 // allow promoting non-lvalue arrays. Warn, then 3326 // force the promotion here. 3327 Diag(LHSExp->getLocStart(), diag::ext_subscript_non_lvalue) << 3328 LHSExp->getSourceRange(); 3329 LHSExp = ImpCastExprToType(LHSExp, Context.getArrayDecayedType(LHSTy), 3330 CK_ArrayToPointerDecay).take(); 3331 LHSTy = LHSExp->getType(); 3332 3333 BaseExpr = LHSExp; 3334 IndexExpr = RHSExp; 3335 ResultType = LHSTy->getAs<PointerType>()->getPointeeType(); 3336 } else if (RHSTy->isArrayType()) { 3337 // Same as previous, except for 123[f().a] case 3338 Diag(RHSExp->getLocStart(), diag::ext_subscript_non_lvalue) << 3339 RHSExp->getSourceRange(); 3340 RHSExp = ImpCastExprToType(RHSExp, Context.getArrayDecayedType(RHSTy), 3341 CK_ArrayToPointerDecay).take(); 3342 RHSTy = RHSExp->getType(); 3343 3344 BaseExpr = RHSExp; 3345 IndexExpr = LHSExp; 3346 ResultType = RHSTy->getAs<PointerType>()->getPointeeType(); 3347 } else { 3348 return ExprError(Diag(LLoc, diag::err_typecheck_subscript_value) 3349 << LHSExp->getSourceRange() << RHSExp->getSourceRange()); 3350 } 3351 // C99 6.5.2.1p1 3352 if (!IndexExpr->getType()->isIntegerType() && !IndexExpr->isTypeDependent()) 3353 return ExprError(Diag(LLoc, diag::err_typecheck_subscript_not_integer) 3354 << IndexExpr->getSourceRange()); 3355 3356 if ((IndexExpr->getType()->isSpecificBuiltinType(BuiltinType::Char_S) || 3357 IndexExpr->getType()->isSpecificBuiltinType(BuiltinType::Char_U)) 3358 && !IndexExpr->isTypeDependent()) 3359 Diag(LLoc, diag::warn_subscript_is_char) << IndexExpr->getSourceRange(); 3360 3361 // C99 6.5.2.1p1: "shall have type "pointer to *object* type". Similarly, 3362 // C++ [expr.sub]p1: The type "T" shall be a completely-defined object 3363 // type. Note that Functions are not objects, and that (in C99 parlance) 3364 // incomplete types are not object types. 3365 if (ResultType->isFunctionType()) { 3366 Diag(BaseExpr->getLocStart(), diag::err_subscript_function_type) 3367 << ResultType << BaseExpr->getSourceRange(); 3368 return ExprError(); 3369 } 3370 3371 if (ResultType->isVoidType() && !getLangOptions().CPlusPlus) { 3372 // GNU extension: subscripting on pointer to void 3373 Diag(LLoc, diag::ext_gnu_void_ptr) 3374 << BaseExpr->getSourceRange(); 3375 3376 // C forbids expressions of unqualified void type from being l-values. 3377 // See IsCForbiddenLValueType. 3378 if (!ResultType.hasQualifiers()) VK = VK_RValue; 3379 } else if (!ResultType->isDependentType() && 3380 RequireCompleteType(LLoc, ResultType, 3381 PDiag(diag::err_subscript_incomplete_type) 3382 << BaseExpr->getSourceRange())) 3383 return ExprError(); 3384 3385 // Diagnose bad cases where we step over interface counts. 3386 if (ResultType->isObjCObjectType() && LangOpts.ObjCNonFragileABI) { 3387 Diag(LLoc, diag::err_subscript_nonfragile_interface) 3388 << ResultType << BaseExpr->getSourceRange(); 3389 return ExprError(); 3390 } 3391 3392 assert(VK == VK_RValue || LangOpts.CPlusPlus || 3393 !IsCForbiddenLValueType(Context, ResultType)); 3394 3395 return Owned(new (Context) ArraySubscriptExpr(LHSExp, RHSExp, 3396 ResultType, VK, OK, RLoc)); 3397} 3398 3399/// Check an ext-vector component access expression. 3400/// 3401/// VK should be set in advance to the value kind of the base 3402/// expression. 3403static QualType 3404CheckExtVectorComponent(Sema &S, QualType baseType, ExprValueKind &VK, 3405 SourceLocation OpLoc, const IdentifierInfo *CompName, 3406 SourceLocation CompLoc) { 3407 // FIXME: Share logic with ExtVectorElementExpr::containsDuplicateElements, 3408 // see FIXME there. 3409 // 3410 // FIXME: This logic can be greatly simplified by splitting it along 3411 // halving/not halving and reworking the component checking. 3412 const ExtVectorType *vecType = baseType->getAs<ExtVectorType>(); 3413 3414 // The vector accessor can't exceed the number of elements. 3415 const char *compStr = CompName->getNameStart(); 3416 3417 // This flag determines whether or not the component is one of the four 3418 // special names that indicate a subset of exactly half the elements are 3419 // to be selected. 3420 bool HalvingSwizzle = false; 3421 3422 // This flag determines whether or not CompName has an 's' char prefix, 3423 // indicating that it is a string of hex values to be used as vector indices. 3424 bool HexSwizzle = *compStr == 's' || *compStr == 'S'; 3425 3426 bool HasRepeated = false; 3427 bool HasIndex[16] = {}; 3428 3429 int Idx; 3430 3431 // Check that we've found one of the special components, or that the component 3432 // names must come from the same set. 3433 if (!strcmp(compStr, "hi") || !strcmp(compStr, "lo") || 3434 !strcmp(compStr, "even") || !strcmp(compStr, "odd")) { 3435 HalvingSwizzle = true; 3436 } else if (!HexSwizzle && 3437 (Idx = vecType->getPointAccessorIdx(*compStr)) != -1) { 3438 do { 3439 if (HasIndex[Idx]) HasRepeated = true; 3440 HasIndex[Idx] = true; 3441 compStr++; 3442 } while (*compStr && (Idx = vecType->getPointAccessorIdx(*compStr)) != -1); 3443 } else { 3444 if (HexSwizzle) compStr++; 3445 while ((Idx = vecType->getNumericAccessorIdx(*compStr)) != -1) { 3446 if (HasIndex[Idx]) HasRepeated = true; 3447 HasIndex[Idx] = true; 3448 compStr++; 3449 } 3450 } 3451 3452 if (!HalvingSwizzle && *compStr) { 3453 // We didn't get to the end of the string. This means the component names 3454 // didn't come from the same set *or* we encountered an illegal name. 3455 S.Diag(OpLoc, diag::err_ext_vector_component_name_illegal) 3456 << llvm::StringRef(compStr, 1) << SourceRange(CompLoc); 3457 return QualType(); 3458 } 3459 3460 // Ensure no component accessor exceeds the width of the vector type it 3461 // operates on. 3462 if (!HalvingSwizzle) { 3463 compStr = CompName->getNameStart(); 3464 3465 if (HexSwizzle) 3466 compStr++; 3467 3468 while (*compStr) { 3469 if (!vecType->isAccessorWithinNumElements(*compStr++)) { 3470 S.Diag(OpLoc, diag::err_ext_vector_component_exceeds_length) 3471 << baseType << SourceRange(CompLoc); 3472 return QualType(); 3473 } 3474 } 3475 } 3476 3477 // The component accessor looks fine - now we need to compute the actual type. 3478 // The vector type is implied by the component accessor. For example, 3479 // vec4.b is a float, vec4.xy is a vec2, vec4.rgb is a vec3, etc. 3480 // vec4.s0 is a float, vec4.s23 is a vec3, etc. 3481 // vec4.hi, vec4.lo, vec4.e, and vec4.o all return vec2. 3482 unsigned CompSize = HalvingSwizzle ? (vecType->getNumElements() + 1) / 2 3483 : CompName->getLength(); 3484 if (HexSwizzle) 3485 CompSize--; 3486 3487 if (CompSize == 1) 3488 return vecType->getElementType(); 3489 3490 if (HasRepeated) VK = VK_RValue; 3491 3492 QualType VT = S.Context.getExtVectorType(vecType->getElementType(), CompSize); 3493 // Now look up the TypeDefDecl from the vector type. Without this, 3494 // diagostics look bad. We want extended vector types to appear built-in. 3495 for (unsigned i = 0, E = S.ExtVectorDecls.size(); i != E; ++i) { 3496 if (S.ExtVectorDecls[i]->getUnderlyingType() == VT) 3497 return S.Context.getTypedefType(S.ExtVectorDecls[i]); 3498 } 3499 return VT; // should never get here (a typedef type should always be found). 3500} 3501 3502static Decl *FindGetterSetterNameDeclFromProtocolList(const ObjCProtocolDecl*PDecl, 3503 IdentifierInfo *Member, 3504 const Selector &Sel, 3505 ASTContext &Context) { 3506 if (Member) 3507 if (ObjCPropertyDecl *PD = PDecl->FindPropertyDeclaration(Member)) 3508 return PD; 3509 if (ObjCMethodDecl *OMD = PDecl->getInstanceMethod(Sel)) 3510 return OMD; 3511 3512 for (ObjCProtocolDecl::protocol_iterator I = PDecl->protocol_begin(), 3513 E = PDecl->protocol_end(); I != E; ++I) { 3514 if (Decl *D = FindGetterSetterNameDeclFromProtocolList(*I, Member, Sel, 3515 Context)) 3516 return D; 3517 } 3518 return 0; 3519} 3520 3521static Decl *FindGetterSetterNameDecl(const ObjCObjectPointerType *QIdTy, 3522 IdentifierInfo *Member, 3523 const Selector &Sel, 3524 ASTContext &Context) { 3525 // Check protocols on qualified interfaces. 3526 Decl *GDecl = 0; 3527 for (ObjCObjectPointerType::qual_iterator I = QIdTy->qual_begin(), 3528 E = QIdTy->qual_end(); I != E; ++I) { 3529 if (Member) 3530 if (ObjCPropertyDecl *PD = (*I)->FindPropertyDeclaration(Member)) { 3531 GDecl = PD; 3532 break; 3533 } 3534 // Also must look for a getter or setter name which uses property syntax. 3535 if (ObjCMethodDecl *OMD = (*I)->getInstanceMethod(Sel)) { 3536 GDecl = OMD; 3537 break; 3538 } 3539 } 3540 if (!GDecl) { 3541 for (ObjCObjectPointerType::qual_iterator I = QIdTy->qual_begin(), 3542 E = QIdTy->qual_end(); I != E; ++I) { 3543 // Search in the protocol-qualifier list of current protocol. 3544 GDecl = FindGetterSetterNameDeclFromProtocolList(*I, Member, Sel, 3545 Context); 3546 if (GDecl) 3547 return GDecl; 3548 } 3549 } 3550 return GDecl; 3551} 3552 3553ExprResult 3554Sema::ActOnDependentMemberExpr(Expr *BaseExpr, QualType BaseType, 3555 bool IsArrow, SourceLocation OpLoc, 3556 const CXXScopeSpec &SS, 3557 NamedDecl *FirstQualifierInScope, 3558 const DeclarationNameInfo &NameInfo, 3559 const TemplateArgumentListInfo *TemplateArgs) { 3560 // Even in dependent contexts, try to diagnose base expressions with 3561 // obviously wrong types, e.g.: 3562 // 3563 // T* t; 3564 // t.f; 3565 // 3566 // In Obj-C++, however, the above expression is valid, since it could be 3567 // accessing the 'f' property if T is an Obj-C interface. The extra check 3568 // allows this, while still reporting an error if T is a struct pointer. 3569 if (!IsArrow) { 3570 const PointerType *PT = BaseType->getAs<PointerType>(); 3571 if (PT && (!getLangOptions().ObjC1 || 3572 PT->getPointeeType()->isRecordType())) { 3573 assert(BaseExpr && "cannot happen with implicit member accesses"); 3574 Diag(NameInfo.getLoc(), diag::err_typecheck_member_reference_struct_union) 3575 << BaseType << BaseExpr->getSourceRange(); 3576 return ExprError(); 3577 } 3578 } 3579 3580 assert(BaseType->isDependentType() || 3581 NameInfo.getName().isDependentName() || 3582 isDependentScopeSpecifier(SS)); 3583 3584 // Get the type being accessed in BaseType. If this is an arrow, the BaseExpr 3585 // must have pointer type, and the accessed type is the pointee. 3586 return Owned(CXXDependentScopeMemberExpr::Create(Context, BaseExpr, BaseType, 3587 IsArrow, OpLoc, 3588 SS.getWithLocInContext(Context), 3589 FirstQualifierInScope, 3590 NameInfo, TemplateArgs)); 3591} 3592 3593/// We know that the given qualified member reference points only to 3594/// declarations which do not belong to the static type of the base 3595/// expression. Diagnose the problem. 3596static void DiagnoseQualifiedMemberReference(Sema &SemaRef, 3597 Expr *BaseExpr, 3598 QualType BaseType, 3599 const CXXScopeSpec &SS, 3600 NamedDecl *rep, 3601 const DeclarationNameInfo &nameInfo) { 3602 // If this is an implicit member access, use a different set of 3603 // diagnostics. 3604 if (!BaseExpr) 3605 return DiagnoseInstanceReference(SemaRef, SS, rep, nameInfo); 3606 3607 SemaRef.Diag(nameInfo.getLoc(), diag::err_qualified_member_of_unrelated) 3608 << SS.getRange() << rep << BaseType; 3609} 3610 3611// Check whether the declarations we found through a nested-name 3612// specifier in a member expression are actually members of the base 3613// type. The restriction here is: 3614// 3615// C++ [expr.ref]p2: 3616// ... In these cases, the id-expression shall name a 3617// member of the class or of one of its base classes. 3618// 3619// So it's perfectly legitimate for the nested-name specifier to name 3620// an unrelated class, and for us to find an overload set including 3621// decls from classes which are not superclasses, as long as the decl 3622// we actually pick through overload resolution is from a superclass. 3623bool Sema::CheckQualifiedMemberReference(Expr *BaseExpr, 3624 QualType BaseType, 3625 const CXXScopeSpec &SS, 3626 const LookupResult &R) { 3627 const RecordType *BaseRT = BaseType->getAs<RecordType>(); 3628 if (!BaseRT) { 3629 // We can't check this yet because the base type is still 3630 // dependent. 3631 assert(BaseType->isDependentType()); 3632 return false; 3633 } 3634 CXXRecordDecl *BaseRecord = cast<CXXRecordDecl>(BaseRT->getDecl()); 3635 3636 for (LookupResult::iterator I = R.begin(), E = R.end(); I != E; ++I) { 3637 // If this is an implicit member reference and we find a 3638 // non-instance member, it's not an error. 3639 if (!BaseExpr && !(*I)->isCXXInstanceMember()) 3640 return false; 3641 3642 // Note that we use the DC of the decl, not the underlying decl. 3643 DeclContext *DC = (*I)->getDeclContext(); 3644 while (DC->isTransparentContext()) 3645 DC = DC->getParent(); 3646 3647 if (!DC->isRecord()) 3648 continue; 3649 3650 llvm::SmallPtrSet<CXXRecordDecl*,4> MemberRecord; 3651 MemberRecord.insert(cast<CXXRecordDecl>(DC)->getCanonicalDecl()); 3652 3653 if (!IsProvablyNotDerivedFrom(*this, BaseRecord, MemberRecord)) 3654 return false; 3655 } 3656 3657 DiagnoseQualifiedMemberReference(*this, BaseExpr, BaseType, SS, 3658 R.getRepresentativeDecl(), 3659 R.getLookupNameInfo()); 3660 return true; 3661} 3662 3663static bool 3664LookupMemberExprInRecord(Sema &SemaRef, LookupResult &R, 3665 SourceRange BaseRange, const RecordType *RTy, 3666 SourceLocation OpLoc, CXXScopeSpec &SS, 3667 bool HasTemplateArgs) { 3668 RecordDecl *RDecl = RTy->getDecl(); 3669 if (SemaRef.RequireCompleteType(OpLoc, QualType(RTy, 0), 3670 SemaRef.PDiag(diag::err_typecheck_incomplete_tag) 3671 << BaseRange)) 3672 return true; 3673 3674 if (HasTemplateArgs) { 3675 // LookupTemplateName doesn't expect these both to exist simultaneously. 3676 QualType ObjectType = SS.isSet() ? QualType() : QualType(RTy, 0); 3677 3678 bool MOUS; 3679 SemaRef.LookupTemplateName(R, 0, SS, ObjectType, false, MOUS); 3680 return false; 3681 } 3682 3683 DeclContext *DC = RDecl; 3684 if (SS.isSet()) { 3685 // If the member name was a qualified-id, look into the 3686 // nested-name-specifier. 3687 DC = SemaRef.computeDeclContext(SS, false); 3688 3689 if (SemaRef.RequireCompleteDeclContext(SS, DC)) { 3690 SemaRef.Diag(SS.getRange().getEnd(), diag::err_typecheck_incomplete_tag) 3691 << SS.getRange() << DC; 3692 return true; 3693 } 3694 3695 assert(DC && "Cannot handle non-computable dependent contexts in lookup"); 3696 3697 if (!isa<TypeDecl>(DC)) { 3698 SemaRef.Diag(R.getNameLoc(), diag::err_qualified_member_nonclass) 3699 << DC << SS.getRange(); 3700 return true; 3701 } 3702 } 3703 3704 // The record definition is complete, now look up the member. 3705 SemaRef.LookupQualifiedName(R, DC); 3706 3707 if (!R.empty()) 3708 return false; 3709 3710 // We didn't find anything with the given name, so try to correct 3711 // for typos. 3712 DeclarationName Name = R.getLookupName(); 3713 if (SemaRef.CorrectTypo(R, 0, &SS, DC, false, Sema::CTC_MemberLookup) && 3714 !R.empty() && 3715 (isa<ValueDecl>(*R.begin()) || isa<FunctionTemplateDecl>(*R.begin()))) { 3716 SemaRef.Diag(R.getNameLoc(), diag::err_no_member_suggest) 3717 << Name << DC << R.getLookupName() << SS.getRange() 3718 << FixItHint::CreateReplacement(R.getNameLoc(), 3719 R.getLookupName().getAsString()); 3720 if (NamedDecl *ND = R.getAsSingle<NamedDecl>()) 3721 SemaRef.Diag(ND->getLocation(), diag::note_previous_decl) 3722 << ND->getDeclName(); 3723 return false; 3724 } else { 3725 R.clear(); 3726 R.setLookupName(Name); 3727 } 3728 3729 return false; 3730} 3731 3732ExprResult 3733Sema::BuildMemberReferenceExpr(Expr *Base, QualType BaseType, 3734 SourceLocation OpLoc, bool IsArrow, 3735 CXXScopeSpec &SS, 3736 NamedDecl *FirstQualifierInScope, 3737 const DeclarationNameInfo &NameInfo, 3738 const TemplateArgumentListInfo *TemplateArgs) { 3739 if (BaseType->isDependentType() || 3740 (SS.isSet() && isDependentScopeSpecifier(SS))) 3741 return ActOnDependentMemberExpr(Base, BaseType, 3742 IsArrow, OpLoc, 3743 SS, FirstQualifierInScope, 3744 NameInfo, TemplateArgs); 3745 3746 LookupResult R(*this, NameInfo, LookupMemberName); 3747 3748 // Implicit member accesses. 3749 if (!Base) { 3750 QualType RecordTy = BaseType; 3751 if (IsArrow) RecordTy = RecordTy->getAs<PointerType>()->getPointeeType(); 3752 if (LookupMemberExprInRecord(*this, R, SourceRange(), 3753 RecordTy->getAs<RecordType>(), 3754 OpLoc, SS, TemplateArgs != 0)) 3755 return ExprError(); 3756 3757 // Explicit member accesses. 3758 } else { 3759 ExprResult BaseResult = Owned(Base); 3760 ExprResult Result = 3761 LookupMemberExpr(R, BaseResult, IsArrow, OpLoc, 3762 SS, /*ObjCImpDecl*/ 0, TemplateArgs != 0); 3763 3764 if (BaseResult.isInvalid()) 3765 return ExprError(); 3766 Base = BaseResult.take(); 3767 3768 if (Result.isInvalid()) { 3769 Owned(Base); 3770 return ExprError(); 3771 } 3772 3773 if (Result.get()) 3774 return move(Result); 3775 3776 // LookupMemberExpr can modify Base, and thus change BaseType 3777 BaseType = Base->getType(); 3778 } 3779 3780 return BuildMemberReferenceExpr(Base, BaseType, 3781 OpLoc, IsArrow, SS, FirstQualifierInScope, 3782 R, TemplateArgs); 3783} 3784 3785ExprResult 3786Sema::BuildMemberReferenceExpr(Expr *BaseExpr, QualType BaseExprType, 3787 SourceLocation OpLoc, bool IsArrow, 3788 const CXXScopeSpec &SS, 3789 NamedDecl *FirstQualifierInScope, 3790 LookupResult &R, 3791 const TemplateArgumentListInfo *TemplateArgs, 3792 bool SuppressQualifierCheck) { 3793 QualType BaseType = BaseExprType; 3794 if (IsArrow) { 3795 assert(BaseType->isPointerType()); 3796 BaseType = BaseType->getAs<PointerType>()->getPointeeType(); 3797 } 3798 R.setBaseObjectType(BaseType); 3799 3800 const DeclarationNameInfo &MemberNameInfo = R.getLookupNameInfo(); 3801 DeclarationName MemberName = MemberNameInfo.getName(); 3802 SourceLocation MemberLoc = MemberNameInfo.getLoc(); 3803 3804 if (R.isAmbiguous()) 3805 return ExprError(); 3806 3807 if (R.empty()) { 3808 // Rederive where we looked up. 3809 DeclContext *DC = (SS.isSet() 3810 ? computeDeclContext(SS, false) 3811 : BaseType->getAs<RecordType>()->getDecl()); 3812 3813 Diag(R.getNameLoc(), diag::err_no_member) 3814 << MemberName << DC 3815 << (BaseExpr ? BaseExpr->getSourceRange() : SourceRange()); 3816 return ExprError(); 3817 } 3818 3819 // Diagnose lookups that find only declarations from a non-base 3820 // type. This is possible for either qualified lookups (which may 3821 // have been qualified with an unrelated type) or implicit member 3822 // expressions (which were found with unqualified lookup and thus 3823 // may have come from an enclosing scope). Note that it's okay for 3824 // lookup to find declarations from a non-base type as long as those 3825 // aren't the ones picked by overload resolution. 3826 if ((SS.isSet() || !BaseExpr || 3827 (isa<CXXThisExpr>(BaseExpr) && 3828 cast<CXXThisExpr>(BaseExpr)->isImplicit())) && 3829 !SuppressQualifierCheck && 3830 CheckQualifiedMemberReference(BaseExpr, BaseType, SS, R)) 3831 return ExprError(); 3832 3833 // Construct an unresolved result if we in fact got an unresolved 3834 // result. 3835 if (R.isOverloadedResult() || R.isUnresolvableResult()) { 3836 // Suppress any lookup-related diagnostics; we'll do these when we 3837 // pick a member. 3838 R.suppressDiagnostics(); 3839 3840 UnresolvedMemberExpr *MemExpr 3841 = UnresolvedMemberExpr::Create(Context, R.isUnresolvableResult(), 3842 BaseExpr, BaseExprType, 3843 IsArrow, OpLoc, 3844 SS.getWithLocInContext(Context), 3845 MemberNameInfo, 3846 TemplateArgs, R.begin(), R.end()); 3847 3848 return Owned(MemExpr); 3849 } 3850 3851 assert(R.isSingleResult()); 3852 DeclAccessPair FoundDecl = R.begin().getPair(); 3853 NamedDecl *MemberDecl = R.getFoundDecl(); 3854 3855 // FIXME: diagnose the presence of template arguments now. 3856 3857 // If the decl being referenced had an error, return an error for this 3858 // sub-expr without emitting another error, in order to avoid cascading 3859 // error cases. 3860 if (MemberDecl->isInvalidDecl()) 3861 return ExprError(); 3862 3863 // Handle the implicit-member-access case. 3864 if (!BaseExpr) { 3865 // If this is not an instance member, convert to a non-member access. 3866 if (!MemberDecl->isCXXInstanceMember()) 3867 return BuildDeclarationNameExpr(SS, R.getLookupNameInfo(), MemberDecl); 3868 3869 SourceLocation Loc = R.getNameLoc(); 3870 if (SS.getRange().isValid()) 3871 Loc = SS.getRange().getBegin(); 3872 BaseExpr = new (Context) CXXThisExpr(Loc, BaseExprType,/*isImplicit=*/true); 3873 } 3874 3875 bool ShouldCheckUse = true; 3876 if (CXXMethodDecl *MD = dyn_cast<CXXMethodDecl>(MemberDecl)) { 3877 // Don't diagnose the use of a virtual member function unless it's 3878 // explicitly qualified. 3879 if (MD->isVirtual() && !SS.isSet()) 3880 ShouldCheckUse = false; 3881 } 3882 3883 // Check the use of this member. 3884 if (ShouldCheckUse && DiagnoseUseOfDecl(MemberDecl, MemberLoc)) { 3885 Owned(BaseExpr); 3886 return ExprError(); 3887 } 3888 3889 // Perform a property load on the base regardless of whether we 3890 // actually need it for the declaration. 3891 if (BaseExpr->getObjectKind() == OK_ObjCProperty) { 3892 ExprResult Result = ConvertPropertyForRValue(BaseExpr); 3893 if (Result.isInvalid()) 3894 return ExprError(); 3895 BaseExpr = Result.take(); 3896 } 3897 3898 if (FieldDecl *FD = dyn_cast<FieldDecl>(MemberDecl)) 3899 return BuildFieldReferenceExpr(*this, BaseExpr, IsArrow, 3900 SS, FD, FoundDecl, MemberNameInfo); 3901 3902 if (IndirectFieldDecl *FD = dyn_cast<IndirectFieldDecl>(MemberDecl)) 3903 // We may have found a field within an anonymous union or struct 3904 // (C++ [class.union]). 3905 return BuildAnonymousStructUnionMemberReference(SS, MemberLoc, FD, 3906 BaseExpr, OpLoc); 3907 3908 if (VarDecl *Var = dyn_cast<VarDecl>(MemberDecl)) { 3909 MarkDeclarationReferenced(MemberLoc, Var); 3910 return Owned(BuildMemberExpr(Context, BaseExpr, IsArrow, SS, 3911 Var, FoundDecl, MemberNameInfo, 3912 Var->getType().getNonReferenceType(), 3913 VK_LValue, OK_Ordinary)); 3914 } 3915 3916 if (CXXMethodDecl *MemberFn = dyn_cast<CXXMethodDecl>(MemberDecl)) { 3917 MarkDeclarationReferenced(MemberLoc, MemberDecl); 3918 return Owned(BuildMemberExpr(Context, BaseExpr, IsArrow, SS, 3919 MemberFn, FoundDecl, MemberNameInfo, 3920 MemberFn->getType(), 3921 MemberFn->isInstance() ? VK_RValue : VK_LValue, 3922 OK_Ordinary)); 3923 } 3924 assert(!isa<FunctionDecl>(MemberDecl) && "member function not C++ method?"); 3925 3926 if (EnumConstantDecl *Enum = dyn_cast<EnumConstantDecl>(MemberDecl)) { 3927 MarkDeclarationReferenced(MemberLoc, MemberDecl); 3928 return Owned(BuildMemberExpr(Context, BaseExpr, IsArrow, SS, 3929 Enum, FoundDecl, MemberNameInfo, 3930 Enum->getType(), VK_RValue, OK_Ordinary)); 3931 } 3932 3933 Owned(BaseExpr); 3934 3935 // We found something that we didn't expect. Complain. 3936 if (isa<TypeDecl>(MemberDecl)) 3937 Diag(MemberLoc, diag::err_typecheck_member_reference_type) 3938 << MemberName << BaseType << int(IsArrow); 3939 else 3940 Diag(MemberLoc, diag::err_typecheck_member_reference_unknown) 3941 << MemberName << BaseType << int(IsArrow); 3942 3943 Diag(MemberDecl->getLocation(), diag::note_member_declared_here) 3944 << MemberName; 3945 R.suppressDiagnostics(); 3946 return ExprError(); 3947} 3948 3949/// Given that normal member access failed on the given expression, 3950/// and given that the expression's type involves builtin-id or 3951/// builtin-Class, decide whether substituting in the redefinition 3952/// types would be profitable. The redefinition type is whatever 3953/// this translation unit tried to typedef to id/Class; we store 3954/// it to the side and then re-use it in places like this. 3955static bool ShouldTryAgainWithRedefinitionType(Sema &S, ExprResult &base) { 3956 const ObjCObjectPointerType *opty 3957 = base.get()->getType()->getAs<ObjCObjectPointerType>(); 3958 if (!opty) return false; 3959 3960 const ObjCObjectType *ty = opty->getObjectType(); 3961 3962 QualType redef; 3963 if (ty->isObjCId()) { 3964 redef = S.Context.ObjCIdRedefinitionType; 3965 } else if (ty->isObjCClass()) { 3966 redef = S.Context.ObjCClassRedefinitionType; 3967 } else { 3968 return false; 3969 } 3970 3971 // Do the substitution as long as the redefinition type isn't just a 3972 // possibly-qualified pointer to builtin-id or builtin-Class again. 3973 opty = redef->getAs<ObjCObjectPointerType>(); 3974 if (opty && !opty->getObjectType()->getInterface() != 0) 3975 return false; 3976 3977 base = S.ImpCastExprToType(base.take(), redef, CK_BitCast); 3978 return true; 3979} 3980 3981/// Look up the given member of the given non-type-dependent 3982/// expression. This can return in one of two ways: 3983/// * If it returns a sentinel null-but-valid result, the caller will 3984/// assume that lookup was performed and the results written into 3985/// the provided structure. It will take over from there. 3986/// * Otherwise, the returned expression will be produced in place of 3987/// an ordinary member expression. 3988/// 3989/// The ObjCImpDecl bit is a gross hack that will need to be properly 3990/// fixed for ObjC++. 3991ExprResult 3992Sema::LookupMemberExpr(LookupResult &R, ExprResult &BaseExpr, 3993 bool &IsArrow, SourceLocation OpLoc, 3994 CXXScopeSpec &SS, 3995 Decl *ObjCImpDecl, bool HasTemplateArgs) { 3996 assert(BaseExpr.get() && "no base expression"); 3997 3998 // Perform default conversions. 3999 BaseExpr = DefaultFunctionArrayConversion(BaseExpr.take()); 4000 4001 if (IsArrow) { 4002 BaseExpr = DefaultLvalueConversion(BaseExpr.take()); 4003 if (BaseExpr.isInvalid()) 4004 return ExprError(); 4005 } 4006 4007 QualType BaseType = BaseExpr.get()->getType(); 4008 assert(!BaseType->isDependentType()); 4009 4010 DeclarationName MemberName = R.getLookupName(); 4011 SourceLocation MemberLoc = R.getNameLoc(); 4012 4013 // For later type-checking purposes, turn arrow accesses into dot 4014 // accesses. The only access type we support that doesn't follow 4015 // the C equivalence "a->b === (*a).b" is ObjC property accesses, 4016 // and those never use arrows, so this is unaffected. 4017 if (IsArrow) { 4018 if (const PointerType *Ptr = BaseType->getAs<PointerType>()) 4019 BaseType = Ptr->getPointeeType(); 4020 else if (const ObjCObjectPointerType *Ptr 4021 = BaseType->getAs<ObjCObjectPointerType>()) 4022 BaseType = Ptr->getPointeeType(); 4023 else if (BaseType->isRecordType()) { 4024 // Recover from arrow accesses to records, e.g.: 4025 // struct MyRecord foo; 4026 // foo->bar 4027 // This is actually well-formed in C++ if MyRecord has an 4028 // overloaded operator->, but that should have been dealt with 4029 // by now. 4030 Diag(OpLoc, diag::err_typecheck_member_reference_suggestion) 4031 << BaseType << int(IsArrow) << BaseExpr.get()->getSourceRange() 4032 << FixItHint::CreateReplacement(OpLoc, "."); 4033 IsArrow = false; 4034 } else { 4035 Diag(MemberLoc, diag::err_typecheck_member_reference_arrow) 4036 << BaseType << BaseExpr.get()->getSourceRange(); 4037 return ExprError(); 4038 } 4039 } 4040 4041 // Handle field access to simple records. 4042 if (const RecordType *RTy = BaseType->getAs<RecordType>()) { 4043 if (LookupMemberExprInRecord(*this, R, BaseExpr.get()->getSourceRange(), 4044 RTy, OpLoc, SS, HasTemplateArgs)) 4045 return ExprError(); 4046 4047 // Returning valid-but-null is how we indicate to the caller that 4048 // the lookup result was filled in. 4049 return Owned((Expr*) 0); 4050 } 4051 4052 // Handle ivar access to Objective-C objects. 4053 if (const ObjCObjectType *OTy = BaseType->getAs<ObjCObjectType>()) { 4054 IdentifierInfo *Member = MemberName.getAsIdentifierInfo(); 4055 4056 // There are three cases for the base type: 4057 // - builtin id (qualified or unqualified) 4058 // - builtin Class (qualified or unqualified) 4059 // - an interface 4060 ObjCInterfaceDecl *IDecl = OTy->getInterface(); 4061 if (!IDecl) { 4062 // There's an implicit 'isa' ivar on all objects. 4063 // But we only actually find it this way on objects of type 'id', 4064 // apparently. 4065 if (OTy->isObjCId() && Member->isStr("isa")) 4066 return Owned(new (Context) ObjCIsaExpr(BaseExpr.take(), IsArrow, MemberLoc, 4067 Context.getObjCClassType())); 4068 4069 if (ShouldTryAgainWithRedefinitionType(*this, BaseExpr)) 4070 return LookupMemberExpr(R, BaseExpr, IsArrow, OpLoc, SS, 4071 ObjCImpDecl, HasTemplateArgs); 4072 goto fail; 4073 } 4074 4075 ObjCInterfaceDecl *ClassDeclared; 4076 ObjCIvarDecl *IV = IDecl->lookupInstanceVariable(Member, ClassDeclared); 4077 4078 if (!IV) { 4079 // Attempt to correct for typos in ivar names. 4080 LookupResult Res(*this, R.getLookupName(), R.getNameLoc(), 4081 LookupMemberName); 4082 if (CorrectTypo(Res, 0, 0, IDecl, false, 4083 IsArrow ? CTC_ObjCIvarLookup 4084 : CTC_ObjCPropertyLookup) && 4085 (IV = Res.getAsSingle<ObjCIvarDecl>())) { 4086 Diag(R.getNameLoc(), 4087 diag::err_typecheck_member_reference_ivar_suggest) 4088 << IDecl->getDeclName() << MemberName << IV->getDeclName() 4089 << FixItHint::CreateReplacement(R.getNameLoc(), 4090 IV->getNameAsString()); 4091 Diag(IV->getLocation(), diag::note_previous_decl) 4092 << IV->getDeclName(); 4093 } else { 4094 Res.clear(); 4095 Res.setLookupName(Member); 4096 4097 Diag(MemberLoc, diag::err_typecheck_member_reference_ivar) 4098 << IDecl->getDeclName() << MemberName 4099 << BaseExpr.get()->getSourceRange(); 4100 return ExprError(); 4101 } 4102 } 4103 4104 // If the decl being referenced had an error, return an error for this 4105 // sub-expr without emitting another error, in order to avoid cascading 4106 // error cases. 4107 if (IV->isInvalidDecl()) 4108 return ExprError(); 4109 4110 // Check whether we can reference this field. 4111 if (DiagnoseUseOfDecl(IV, MemberLoc)) 4112 return ExprError(); 4113 if (IV->getAccessControl() != ObjCIvarDecl::Public && 4114 IV->getAccessControl() != ObjCIvarDecl::Package) { 4115 ObjCInterfaceDecl *ClassOfMethodDecl = 0; 4116 if (ObjCMethodDecl *MD = getCurMethodDecl()) 4117 ClassOfMethodDecl = MD->getClassInterface(); 4118 else if (ObjCImpDecl && getCurFunctionDecl()) { 4119 // Case of a c-function declared inside an objc implementation. 4120 // FIXME: For a c-style function nested inside an objc implementation 4121 // class, there is no implementation context available, so we pass 4122 // down the context as argument to this routine. Ideally, this context 4123 // need be passed down in the AST node and somehow calculated from the 4124 // AST for a function decl. 4125 if (ObjCImplementationDecl *IMPD = 4126 dyn_cast<ObjCImplementationDecl>(ObjCImpDecl)) 4127 ClassOfMethodDecl = IMPD->getClassInterface(); 4128 else if (ObjCCategoryImplDecl* CatImplClass = 4129 dyn_cast<ObjCCategoryImplDecl>(ObjCImpDecl)) 4130 ClassOfMethodDecl = CatImplClass->getClassInterface(); 4131 } 4132 4133 if (IV->getAccessControl() == ObjCIvarDecl::Private) { 4134 if (ClassDeclared != IDecl || 4135 ClassOfMethodDecl != ClassDeclared) 4136 Diag(MemberLoc, diag::error_private_ivar_access) 4137 << IV->getDeclName(); 4138 } else if (!IDecl->isSuperClassOf(ClassOfMethodDecl)) 4139 // @protected 4140 Diag(MemberLoc, diag::error_protected_ivar_access) 4141 << IV->getDeclName(); 4142 } 4143 4144 return Owned(new (Context) ObjCIvarRefExpr(IV, IV->getType(), 4145 MemberLoc, BaseExpr.take(), 4146 IsArrow)); 4147 } 4148 4149 // Objective-C property access. 4150 const ObjCObjectPointerType *OPT; 4151 if (!IsArrow && (OPT = BaseType->getAs<ObjCObjectPointerType>())) { 4152 // This actually uses the base as an r-value. 4153 BaseExpr = DefaultLvalueConversion(BaseExpr.take()); 4154 if (BaseExpr.isInvalid()) 4155 return ExprError(); 4156 4157 assert(Context.hasSameUnqualifiedType(BaseType, BaseExpr.get()->getType())); 4158 4159 IdentifierInfo *Member = MemberName.getAsIdentifierInfo(); 4160 4161 const ObjCObjectType *OT = OPT->getObjectType(); 4162 4163 // id, with and without qualifiers. 4164 if (OT->isObjCId()) { 4165 // Check protocols on qualified interfaces. 4166 Selector Sel = PP.getSelectorTable().getNullarySelector(Member); 4167 if (Decl *PMDecl = FindGetterSetterNameDecl(OPT, Member, Sel, Context)) { 4168 if (ObjCPropertyDecl *PD = dyn_cast<ObjCPropertyDecl>(PMDecl)) { 4169 // Check the use of this declaration 4170 if (DiagnoseUseOfDecl(PD, MemberLoc)) 4171 return ExprError(); 4172 4173 return Owned(new (Context) ObjCPropertyRefExpr(PD, PD->getType(), 4174 VK_LValue, 4175 OK_ObjCProperty, 4176 MemberLoc, 4177 BaseExpr.take())); 4178 } 4179 4180 if (ObjCMethodDecl *OMD = dyn_cast<ObjCMethodDecl>(PMDecl)) { 4181 // Check the use of this method. 4182 if (DiagnoseUseOfDecl(OMD, MemberLoc)) 4183 return ExprError(); 4184 Selector SetterSel = 4185 SelectorTable::constructSetterName(PP.getIdentifierTable(), 4186 PP.getSelectorTable(), Member); 4187 ObjCMethodDecl *SMD = 0; 4188 if (Decl *SDecl = FindGetterSetterNameDecl(OPT, /*Property id*/0, 4189 SetterSel, Context)) 4190 SMD = dyn_cast<ObjCMethodDecl>(SDecl); 4191 QualType PType = OMD->getSendResultType(); 4192 4193 ExprValueKind VK = VK_LValue; 4194 if (!getLangOptions().CPlusPlus && 4195 IsCForbiddenLValueType(Context, PType)) 4196 VK = VK_RValue; 4197 ExprObjectKind OK = (VK == VK_RValue ? OK_Ordinary : OK_ObjCProperty); 4198 4199 return Owned(new (Context) ObjCPropertyRefExpr(OMD, SMD, PType, 4200 VK, OK, 4201 MemberLoc, BaseExpr.take())); 4202 } 4203 } 4204 // Use of id.member can only be for a property reference. Do not 4205 // use the 'id' redefinition in this case. 4206 if (IsArrow && ShouldTryAgainWithRedefinitionType(*this, BaseExpr)) 4207 return LookupMemberExpr(R, BaseExpr, IsArrow, OpLoc, SS, 4208 ObjCImpDecl, HasTemplateArgs); 4209 4210 return ExprError(Diag(MemberLoc, diag::err_property_not_found) 4211 << MemberName << BaseType); 4212 } 4213 4214 // 'Class', unqualified only. 4215 if (OT->isObjCClass()) { 4216 // Only works in a method declaration (??!). 4217 ObjCMethodDecl *MD = getCurMethodDecl(); 4218 if (!MD) { 4219 if (ShouldTryAgainWithRedefinitionType(*this, BaseExpr)) 4220 return LookupMemberExpr(R, BaseExpr, IsArrow, OpLoc, SS, 4221 ObjCImpDecl, HasTemplateArgs); 4222 4223 goto fail; 4224 } 4225 4226 // Also must look for a getter name which uses property syntax. 4227 Selector Sel = PP.getSelectorTable().getNullarySelector(Member); 4228 ObjCInterfaceDecl *IFace = MD->getClassInterface(); 4229 ObjCMethodDecl *Getter; 4230 if ((Getter = IFace->lookupClassMethod(Sel))) { 4231 // Check the use of this method. 4232 if (DiagnoseUseOfDecl(Getter, MemberLoc)) 4233 return ExprError(); 4234 } else 4235 Getter = IFace->lookupPrivateMethod(Sel, false); 4236 // If we found a getter then this may be a valid dot-reference, we 4237 // will look for the matching setter, in case it is needed. 4238 Selector SetterSel = 4239 SelectorTable::constructSetterName(PP.getIdentifierTable(), 4240 PP.getSelectorTable(), Member); 4241 ObjCMethodDecl *Setter = IFace->lookupClassMethod(SetterSel); 4242 if (!Setter) { 4243 // If this reference is in an @implementation, also check for 'private' 4244 // methods. 4245 Setter = IFace->lookupPrivateMethod(SetterSel, false); 4246 } 4247 // Look through local category implementations associated with the class. 4248 if (!Setter) 4249 Setter = IFace->getCategoryClassMethod(SetterSel); 4250 4251 if (Setter && DiagnoseUseOfDecl(Setter, MemberLoc)) 4252 return ExprError(); 4253 4254 if (Getter || Setter) { 4255 QualType PType; 4256 4257 ExprValueKind VK = VK_LValue; 4258 if (Getter) { 4259 PType = Getter->getSendResultType(); 4260 if (!getLangOptions().CPlusPlus && 4261 IsCForbiddenLValueType(Context, PType)) 4262 VK = VK_RValue; 4263 } else { 4264 // Get the expression type from Setter's incoming parameter. 4265 PType = (*(Setter->param_end() -1))->getType(); 4266 } 4267 ExprObjectKind OK = (VK == VK_RValue ? OK_Ordinary : OK_ObjCProperty); 4268 4269 // FIXME: we must check that the setter has property type. 4270 return Owned(new (Context) ObjCPropertyRefExpr(Getter, Setter, 4271 PType, VK, OK, 4272 MemberLoc, BaseExpr.take())); 4273 } 4274 4275 if (ShouldTryAgainWithRedefinitionType(*this, BaseExpr)) 4276 return LookupMemberExpr(R, BaseExpr, IsArrow, OpLoc, SS, 4277 ObjCImpDecl, HasTemplateArgs); 4278 4279 return ExprError(Diag(MemberLoc, diag::err_property_not_found) 4280 << MemberName << BaseType); 4281 } 4282 4283 // Normal property access. 4284 return HandleExprPropertyRefExpr(OPT, BaseExpr.get(), MemberName, MemberLoc, 4285 SourceLocation(), QualType(), false); 4286 } 4287 4288 // Handle 'field access' to vectors, such as 'V.xx'. 4289 if (BaseType->isExtVectorType()) { 4290 // FIXME: this expr should store IsArrow. 4291 IdentifierInfo *Member = MemberName.getAsIdentifierInfo(); 4292 ExprValueKind VK = (IsArrow ? VK_LValue : BaseExpr.get()->getValueKind()); 4293 QualType ret = CheckExtVectorComponent(*this, BaseType, VK, OpLoc, 4294 Member, MemberLoc); 4295 if (ret.isNull()) 4296 return ExprError(); 4297 4298 return Owned(new (Context) ExtVectorElementExpr(ret, VK, BaseExpr.take(), 4299 *Member, MemberLoc)); 4300 } 4301 4302 // Adjust builtin-sel to the appropriate redefinition type if that's 4303 // not just a pointer to builtin-sel again. 4304 if (IsArrow && 4305 BaseType->isSpecificBuiltinType(BuiltinType::ObjCSel) && 4306 !Context.ObjCSelRedefinitionType->isObjCSelType()) { 4307 BaseExpr = ImpCastExprToType(BaseExpr.take(), Context.ObjCSelRedefinitionType, 4308 CK_BitCast); 4309 return LookupMemberExpr(R, BaseExpr, IsArrow, OpLoc, SS, 4310 ObjCImpDecl, HasTemplateArgs); 4311 } 4312 4313 // Failure cases. 4314 fail: 4315 4316 // Recover from dot accesses to pointers, e.g.: 4317 // type *foo; 4318 // foo.bar 4319 // This is actually well-formed in two cases: 4320 // - 'type' is an Objective C type 4321 // - 'bar' is a pseudo-destructor name which happens to refer to 4322 // the appropriate pointer type 4323 if (const PointerType *Ptr = BaseType->getAs<PointerType>()) { 4324 if (!IsArrow && Ptr->getPointeeType()->isRecordType() && 4325 MemberName.getNameKind() != DeclarationName::CXXDestructorName) { 4326 Diag(OpLoc, diag::err_typecheck_member_reference_suggestion) 4327 << BaseType << int(IsArrow) << BaseExpr.get()->getSourceRange() 4328 << FixItHint::CreateReplacement(OpLoc, "->"); 4329 4330 // Recurse as an -> access. 4331 IsArrow = true; 4332 return LookupMemberExpr(R, BaseExpr, IsArrow, OpLoc, SS, 4333 ObjCImpDecl, HasTemplateArgs); 4334 } 4335 } 4336 4337 // If the user is trying to apply -> or . to a function name, it's probably 4338 // because they forgot parentheses to call that function. 4339 bool TryCall = false; 4340 bool Overloaded = false; 4341 UnresolvedSet<8> AllOverloads; 4342 if (const OverloadExpr *Overloads = dyn_cast<OverloadExpr>(BaseExpr.get())) { 4343 AllOverloads.append(Overloads->decls_begin(), Overloads->decls_end()); 4344 TryCall = true; 4345 Overloaded = true; 4346 } else if (DeclRefExpr *DeclRef = dyn_cast<DeclRefExpr>(BaseExpr.get())) { 4347 if (FunctionDecl* Fun = dyn_cast<FunctionDecl>(DeclRef->getDecl())) { 4348 AllOverloads.addDecl(Fun); 4349 TryCall = true; 4350 } 4351 } 4352 4353 if (TryCall) { 4354 // Plunder the overload set for something that would make the member 4355 // expression valid. 4356 UnresolvedSet<4> ViableOverloads; 4357 bool HasViableZeroArgOverload = false; 4358 for (OverloadExpr::decls_iterator it = AllOverloads.begin(), 4359 DeclsEnd = AllOverloads.end(); it != DeclsEnd; ++it) { 4360 // Our overload set may include TemplateDecls, which we'll ignore for the 4361 // purposes of determining whether we can issue a '()' fixit. 4362 if (const FunctionDecl *OverloadDecl = dyn_cast<FunctionDecl>(*it)) { 4363 QualType ResultTy = OverloadDecl->getResultType(); 4364 if ((!IsArrow && ResultTy->isRecordType()) || 4365 (IsArrow && ResultTy->isPointerType() && 4366 ResultTy->getPointeeType()->isRecordType())) { 4367 ViableOverloads.addDecl(*it); 4368 if (OverloadDecl->getMinRequiredArguments() == 0) { 4369 HasViableZeroArgOverload = true; 4370 } 4371 } 4372 } 4373 } 4374 4375 if (!HasViableZeroArgOverload || ViableOverloads.size() != 1) { 4376 Diag(BaseExpr.get()->getExprLoc(), diag::err_member_reference_needs_call) 4377 << (AllOverloads.size() > 1) << 0 4378 << BaseExpr.get()->getSourceRange(); 4379 int ViableOverloadCount = ViableOverloads.size(); 4380 int I; 4381 for (I = 0; I < ViableOverloadCount; ++I) { 4382 // FIXME: Magic number for max shown overloads stolen from 4383 // OverloadCandidateSet::NoteCandidates. 4384 if (I >= 4 && Diags.getShowOverloads() == Diagnostic::Ovl_Best) { 4385 break; 4386 } 4387 Diag(ViableOverloads[I].getDecl()->getSourceRange().getBegin(), 4388 diag::note_member_ref_possible_intended_overload); 4389 } 4390 if (I != ViableOverloadCount) { 4391 Diag(BaseExpr.get()->getExprLoc(), diag::note_ovl_too_many_candidates) 4392 << int(ViableOverloadCount - I); 4393 } 4394 return ExprError(); 4395 } 4396 } else { 4397 // We don't have an expression that's convenient to get a Decl from, but we 4398 // can at least check if the type is "function of 0 arguments which returns 4399 // an acceptable type". 4400 const FunctionType *Fun = NULL; 4401 if (const PointerType *Ptr = BaseType->getAs<PointerType>()) { 4402 if ((Fun = Ptr->getPointeeType()->getAs<FunctionType>())) { 4403 TryCall = true; 4404 } 4405 } else if ((Fun = BaseType->getAs<FunctionType>())) { 4406 TryCall = true; 4407 } 4408 4409 if (TryCall) { 4410 if (const FunctionProtoType *FPT = dyn_cast<FunctionProtoType>(Fun)) { 4411 if (FPT->getNumArgs() == 0) { 4412 QualType ResultTy = Fun->getResultType(); 4413 TryCall = (!IsArrow && ResultTy->isRecordType()) || 4414 (IsArrow && ResultTy->isPointerType() && 4415 ResultTy->getPointeeType()->isRecordType()); 4416 } 4417 } 4418 } 4419 } 4420 4421 if (TryCall) { 4422 // At this point, we know BaseExpr looks like it's potentially callable with 4423 // 0 arguments, and that it returns something of a reasonable type, so we 4424 // can emit a fixit and carry on pretending that BaseExpr was actually a 4425 // CallExpr. 4426 SourceLocation ParenInsertionLoc = 4427 PP.getLocForEndOfToken(BaseExpr.get()->getLocEnd()); 4428 Diag(BaseExpr.get()->getExprLoc(), diag::err_member_reference_needs_call) 4429 << int(Overloaded) << 1 4430 << BaseExpr.get()->getSourceRange() 4431 << FixItHint::CreateInsertion(ParenInsertionLoc, "()"); 4432 ExprResult NewBase = ActOnCallExpr(0, BaseExpr.take(), ParenInsertionLoc, 4433 MultiExprArg(*this, 0, 0), 4434 ParenInsertionLoc); 4435 if (NewBase.isInvalid()) 4436 return ExprError(); 4437 BaseExpr = NewBase; 4438 BaseExpr = DefaultFunctionArrayConversion(BaseExpr.take()); 4439 return LookupMemberExpr(R, BaseExpr, IsArrow, OpLoc, SS, 4440 ObjCImpDecl, HasTemplateArgs); 4441 } 4442 4443 Diag(MemberLoc, diag::err_typecheck_member_reference_struct_union) 4444 << BaseType << BaseExpr.get()->getSourceRange(); 4445 4446 return ExprError(); 4447} 4448 4449/// The main callback when the parser finds something like 4450/// expression . [nested-name-specifier] identifier 4451/// expression -> [nested-name-specifier] identifier 4452/// where 'identifier' encompasses a fairly broad spectrum of 4453/// possibilities, including destructor and operator references. 4454/// 4455/// \param OpKind either tok::arrow or tok::period 4456/// \param HasTrailingLParen whether the next token is '(', which 4457/// is used to diagnose mis-uses of special members that can 4458/// only be called 4459/// \param ObjCImpDecl the current ObjC @implementation decl; 4460/// this is an ugly hack around the fact that ObjC @implementations 4461/// aren't properly put in the context chain 4462ExprResult Sema::ActOnMemberAccessExpr(Scope *S, Expr *Base, 4463 SourceLocation OpLoc, 4464 tok::TokenKind OpKind, 4465 CXXScopeSpec &SS, 4466 UnqualifiedId &Id, 4467 Decl *ObjCImpDecl, 4468 bool HasTrailingLParen) { 4469 if (SS.isSet() && SS.isInvalid()) 4470 return ExprError(); 4471 4472 // Warn about the explicit constructor calls Microsoft extension. 4473 if (getLangOptions().Microsoft && 4474 Id.getKind() == UnqualifiedId::IK_ConstructorName) 4475 Diag(Id.getSourceRange().getBegin(), 4476 diag::ext_ms_explicit_constructor_call); 4477 4478 TemplateArgumentListInfo TemplateArgsBuffer; 4479 4480 // Decompose the name into its component parts. 4481 DeclarationNameInfo NameInfo; 4482 const TemplateArgumentListInfo *TemplateArgs; 4483 DecomposeUnqualifiedId(*this, Id, TemplateArgsBuffer, 4484 NameInfo, TemplateArgs); 4485 4486 DeclarationName Name = NameInfo.getName(); 4487 bool IsArrow = (OpKind == tok::arrow); 4488 4489 NamedDecl *FirstQualifierInScope 4490 = (!SS.isSet() ? 0 : FindFirstQualifierInScope(S, 4491 static_cast<NestedNameSpecifier*>(SS.getScopeRep()))); 4492 4493 // This is a postfix expression, so get rid of ParenListExprs. 4494 ExprResult Result = MaybeConvertParenListExprToParenExpr(S, Base); 4495 if (Result.isInvalid()) return ExprError(); 4496 Base = Result.take(); 4497 4498 if (Base->getType()->isDependentType() || Name.isDependentName() || 4499 isDependentScopeSpecifier(SS)) { 4500 Result = ActOnDependentMemberExpr(Base, Base->getType(), 4501 IsArrow, OpLoc, 4502 SS, FirstQualifierInScope, 4503 NameInfo, TemplateArgs); 4504 } else { 4505 LookupResult R(*this, NameInfo, LookupMemberName); 4506 ExprResult BaseResult = Owned(Base); 4507 Result = LookupMemberExpr(R, BaseResult, IsArrow, OpLoc, 4508 SS, ObjCImpDecl, TemplateArgs != 0); 4509 if (BaseResult.isInvalid()) 4510 return ExprError(); 4511 Base = BaseResult.take(); 4512 4513 if (Result.isInvalid()) { 4514 Owned(Base); 4515 return ExprError(); 4516 } 4517 4518 if (Result.get()) { 4519 // The only way a reference to a destructor can be used is to 4520 // immediately call it, which falls into this case. If the 4521 // next token is not a '(', produce a diagnostic and build the 4522 // call now. 4523 if (!HasTrailingLParen && 4524 Id.getKind() == UnqualifiedId::IK_DestructorName) 4525 return DiagnoseDtorReference(NameInfo.getLoc(), Result.get()); 4526 4527 return move(Result); 4528 } 4529 4530 Result = BuildMemberReferenceExpr(Base, Base->getType(), 4531 OpLoc, IsArrow, SS, FirstQualifierInScope, 4532 R, TemplateArgs); 4533 } 4534 4535 return move(Result); 4536} 4537 4538ExprResult Sema::BuildCXXDefaultArgExpr(SourceLocation CallLoc, 4539 FunctionDecl *FD, 4540 ParmVarDecl *Param) { 4541 if (Param->hasUnparsedDefaultArg()) { 4542 Diag(CallLoc, 4543 diag::err_use_of_default_argument_to_function_declared_later) << 4544 FD << cast<CXXRecordDecl>(FD->getDeclContext())->getDeclName(); 4545 Diag(UnparsedDefaultArgLocs[Param], 4546 diag::note_default_argument_declared_here); 4547 return ExprError(); 4548 } 4549 4550 if (Param->hasUninstantiatedDefaultArg()) { 4551 Expr *UninstExpr = Param->getUninstantiatedDefaultArg(); 4552 4553 // Instantiate the expression. 4554 MultiLevelTemplateArgumentList ArgList 4555 = getTemplateInstantiationArgs(FD, 0, /*RelativeToPrimary=*/true); 4556 4557 std::pair<const TemplateArgument *, unsigned> Innermost 4558 = ArgList.getInnermost(); 4559 InstantiatingTemplate Inst(*this, CallLoc, Param, Innermost.first, 4560 Innermost.second); 4561 4562 ExprResult Result; 4563 { 4564 // C++ [dcl.fct.default]p5: 4565 // The names in the [default argument] expression are bound, and 4566 // the semantic constraints are checked, at the point where the 4567 // default argument expression appears. 4568 ContextRAII SavedContext(*this, FD); 4569 Result = SubstExpr(UninstExpr, ArgList); 4570 } 4571 if (Result.isInvalid()) 4572 return ExprError(); 4573 4574 // Check the expression as an initializer for the parameter. 4575 InitializedEntity Entity 4576 = InitializedEntity::InitializeParameter(Context, Param); 4577 InitializationKind Kind 4578 = InitializationKind::CreateCopy(Param->getLocation(), 4579 /*FIXME:EqualLoc*/UninstExpr->getSourceRange().getBegin()); 4580 Expr *ResultE = Result.takeAs<Expr>(); 4581 4582 InitializationSequence InitSeq(*this, Entity, Kind, &ResultE, 1); 4583 Result = InitSeq.Perform(*this, Entity, Kind, 4584 MultiExprArg(*this, &ResultE, 1)); 4585 if (Result.isInvalid()) 4586 return ExprError(); 4587 4588 // Build the default argument expression. 4589 return Owned(CXXDefaultArgExpr::Create(Context, CallLoc, Param, 4590 Result.takeAs<Expr>())); 4591 } 4592 4593 // If the default expression creates temporaries, we need to 4594 // push them to the current stack of expression temporaries so they'll 4595 // be properly destroyed. 4596 // FIXME: We should really be rebuilding the default argument with new 4597 // bound temporaries; see the comment in PR5810. 4598 for (unsigned i = 0, e = Param->getNumDefaultArgTemporaries(); i != e; ++i) { 4599 CXXTemporary *Temporary = Param->getDefaultArgTemporary(i); 4600 MarkDeclarationReferenced(Param->getDefaultArg()->getLocStart(), 4601 const_cast<CXXDestructorDecl*>(Temporary->getDestructor())); 4602 ExprTemporaries.push_back(Temporary); 4603 } 4604 4605 // We already type-checked the argument, so we know it works. 4606 // Just mark all of the declarations in this potentially-evaluated expression 4607 // as being "referenced". 4608 MarkDeclarationsReferencedInExpr(Param->getDefaultArg()); 4609 return Owned(CXXDefaultArgExpr::Create(Context, CallLoc, Param)); 4610} 4611 4612/// ConvertArgumentsForCall - Converts the arguments specified in 4613/// Args/NumArgs to the parameter types of the function FDecl with 4614/// function prototype Proto. Call is the call expression itself, and 4615/// Fn is the function expression. For a C++ member function, this 4616/// routine does not attempt to convert the object argument. Returns 4617/// true if the call is ill-formed. 4618bool 4619Sema::ConvertArgumentsForCall(CallExpr *Call, Expr *Fn, 4620 FunctionDecl *FDecl, 4621 const FunctionProtoType *Proto, 4622 Expr **Args, unsigned NumArgs, 4623 SourceLocation RParenLoc) { 4624 // Bail out early if calling a builtin with custom typechecking. 4625 // We don't need to do this in the 4626 if (FDecl) 4627 if (unsigned ID = FDecl->getBuiltinID()) 4628 if (Context.BuiltinInfo.hasCustomTypechecking(ID)) 4629 return false; 4630 4631 // C99 6.5.2.2p7 - the arguments are implicitly converted, as if by 4632 // assignment, to the types of the corresponding parameter, ... 4633 unsigned NumArgsInProto = Proto->getNumArgs(); 4634 bool Invalid = false; 4635 4636 // If too few arguments are available (and we don't have default 4637 // arguments for the remaining parameters), don't make the call. 4638 if (NumArgs < NumArgsInProto) { 4639 if (!FDecl || NumArgs < FDecl->getMinRequiredArguments()) 4640 return Diag(RParenLoc, diag::err_typecheck_call_too_few_args) 4641 << Fn->getType()->isBlockPointerType() 4642 << NumArgsInProto << NumArgs << Fn->getSourceRange(); 4643 Call->setNumArgs(Context, NumArgsInProto); 4644 } 4645 4646 // If too many are passed and not variadic, error on the extras and drop 4647 // them. 4648 if (NumArgs > NumArgsInProto) { 4649 if (!Proto->isVariadic()) { 4650 Diag(Args[NumArgsInProto]->getLocStart(), 4651 diag::err_typecheck_call_too_many_args) 4652 << Fn->getType()->isBlockPointerType() 4653 << NumArgsInProto << NumArgs << Fn->getSourceRange() 4654 << SourceRange(Args[NumArgsInProto]->getLocStart(), 4655 Args[NumArgs-1]->getLocEnd()); 4656 4657 // Emit the location of the prototype. 4658 if (FDecl && !FDecl->getBuiltinID()) 4659 Diag(FDecl->getLocStart(), 4660 diag::note_typecheck_call_too_many_args) 4661 << FDecl; 4662 4663 // This deletes the extra arguments. 4664 Call->setNumArgs(Context, NumArgsInProto); 4665 return true; 4666 } 4667 } 4668 llvm::SmallVector<Expr *, 8> AllArgs; 4669 VariadicCallType CallType = 4670 Proto->isVariadic() ? VariadicFunction : VariadicDoesNotApply; 4671 if (Fn->getType()->isBlockPointerType()) 4672 CallType = VariadicBlock; // Block 4673 else if (isa<MemberExpr>(Fn)) 4674 CallType = VariadicMethod; 4675 Invalid = GatherArgumentsForCall(Call->getSourceRange().getBegin(), FDecl, 4676 Proto, 0, Args, NumArgs, AllArgs, CallType); 4677 if (Invalid) 4678 return true; 4679 unsigned TotalNumArgs = AllArgs.size(); 4680 for (unsigned i = 0; i < TotalNumArgs; ++i) 4681 Call->setArg(i, AllArgs[i]); 4682 4683 return false; 4684} 4685 4686bool Sema::GatherArgumentsForCall(SourceLocation CallLoc, 4687 FunctionDecl *FDecl, 4688 const FunctionProtoType *Proto, 4689 unsigned FirstProtoArg, 4690 Expr **Args, unsigned NumArgs, 4691 llvm::SmallVector<Expr *, 8> &AllArgs, 4692 VariadicCallType CallType) { 4693 unsigned NumArgsInProto = Proto->getNumArgs(); 4694 unsigned NumArgsToCheck = NumArgs; 4695 bool Invalid = false; 4696 if (NumArgs != NumArgsInProto) 4697 // Use default arguments for missing arguments 4698 NumArgsToCheck = NumArgsInProto; 4699 unsigned ArgIx = 0; 4700 // Continue to check argument types (even if we have too few/many args). 4701 for (unsigned i = FirstProtoArg; i != NumArgsToCheck; i++) { 4702 QualType ProtoArgType = Proto->getArgType(i); 4703 4704 Expr *Arg; 4705 if (ArgIx < NumArgs) { 4706 Arg = Args[ArgIx++]; 4707 4708 if (RequireCompleteType(Arg->getSourceRange().getBegin(), 4709 ProtoArgType, 4710 PDiag(diag::err_call_incomplete_argument) 4711 << Arg->getSourceRange())) 4712 return true; 4713 4714 // Pass the argument 4715 ParmVarDecl *Param = 0; 4716 if (FDecl && i < FDecl->getNumParams()) 4717 Param = FDecl->getParamDecl(i); 4718 4719 InitializedEntity Entity = 4720 Param? InitializedEntity::InitializeParameter(Context, Param) 4721 : InitializedEntity::InitializeParameter(Context, ProtoArgType); 4722 ExprResult ArgE = PerformCopyInitialization(Entity, 4723 SourceLocation(), 4724 Owned(Arg)); 4725 if (ArgE.isInvalid()) 4726 return true; 4727 4728 Arg = ArgE.takeAs<Expr>(); 4729 } else { 4730 ParmVarDecl *Param = FDecl->getParamDecl(i); 4731 4732 ExprResult ArgExpr = 4733 BuildCXXDefaultArgExpr(CallLoc, FDecl, Param); 4734 if (ArgExpr.isInvalid()) 4735 return true; 4736 4737 Arg = ArgExpr.takeAs<Expr>(); 4738 } 4739 AllArgs.push_back(Arg); 4740 } 4741 4742 // If this is a variadic call, handle args passed through "...". 4743 if (CallType != VariadicDoesNotApply) { 4744 4745 // Assume that extern "C" functions with variadic arguments that 4746 // return __unknown_anytype aren't *really* variadic. 4747 if (Proto->getResultType() == Context.UnknownAnyTy && 4748 FDecl && FDecl->isExternC()) { 4749 for (unsigned i = ArgIx; i != NumArgs; ++i) { 4750 ExprResult arg; 4751 if (isa<ExplicitCastExpr>(Args[i]->IgnoreParens())) 4752 arg = DefaultFunctionArrayLvalueConversion(Args[i]); 4753 else 4754 arg = DefaultVariadicArgumentPromotion(Args[i], CallType, FDecl); 4755 Invalid |= arg.isInvalid(); 4756 AllArgs.push_back(arg.take()); 4757 } 4758 4759 // Otherwise do argument promotion, (C99 6.5.2.2p7). 4760 } else { 4761 for (unsigned i = ArgIx; i != NumArgs; ++i) { 4762 ExprResult Arg = DefaultVariadicArgumentPromotion(Args[i], CallType, FDecl); 4763 Invalid |= Arg.isInvalid(); 4764 AllArgs.push_back(Arg.take()); 4765 } 4766 } 4767 } 4768 return Invalid; 4769} 4770 4771/// Given a function expression of unknown-any type, try to rebuild it 4772/// to have a function type. 4773static ExprResult rebuildUnknownAnyFunction(Sema &S, Expr *fn); 4774 4775/// ActOnCallExpr - Handle a call to Fn with the specified array of arguments. 4776/// This provides the location of the left/right parens and a list of comma 4777/// locations. 4778ExprResult 4779Sema::ActOnCallExpr(Scope *S, Expr *Fn, SourceLocation LParenLoc, 4780 MultiExprArg args, SourceLocation RParenLoc, 4781 Expr *ExecConfig) { 4782 unsigned NumArgs = args.size(); 4783 4784 // Since this might be a postfix expression, get rid of ParenListExprs. 4785 ExprResult Result = MaybeConvertParenListExprToParenExpr(S, Fn); 4786 if (Result.isInvalid()) return ExprError(); 4787 Fn = Result.take(); 4788 4789 Expr **Args = args.release(); 4790 4791 if (getLangOptions().CPlusPlus) { 4792 // If this is a pseudo-destructor expression, build the call immediately. 4793 if (isa<CXXPseudoDestructorExpr>(Fn)) { 4794 if (NumArgs > 0) { 4795 // Pseudo-destructor calls should not have any arguments. 4796 Diag(Fn->getLocStart(), diag::err_pseudo_dtor_call_with_args) 4797 << FixItHint::CreateRemoval( 4798 SourceRange(Args[0]->getLocStart(), 4799 Args[NumArgs-1]->getLocEnd())); 4800 4801 NumArgs = 0; 4802 } 4803 4804 return Owned(new (Context) CallExpr(Context, Fn, 0, 0, Context.VoidTy, 4805 VK_RValue, RParenLoc)); 4806 } 4807 4808 // Determine whether this is a dependent call inside a C++ template, 4809 // in which case we won't do any semantic analysis now. 4810 // FIXME: Will need to cache the results of name lookup (including ADL) in 4811 // Fn. 4812 bool Dependent = false; 4813 if (Fn->isTypeDependent()) 4814 Dependent = true; 4815 else if (Expr::hasAnyTypeDependentArguments(Args, NumArgs)) 4816 Dependent = true; 4817 4818 if (Dependent) { 4819 if (ExecConfig) { 4820 return Owned(new (Context) CUDAKernelCallExpr( 4821 Context, Fn, cast<CallExpr>(ExecConfig), Args, NumArgs, 4822 Context.DependentTy, VK_RValue, RParenLoc)); 4823 } else { 4824 return Owned(new (Context) CallExpr(Context, Fn, Args, NumArgs, 4825 Context.DependentTy, VK_RValue, 4826 RParenLoc)); 4827 } 4828 } 4829 4830 // Determine whether this is a call to an object (C++ [over.call.object]). 4831 if (Fn->getType()->isRecordType()) 4832 return Owned(BuildCallToObjectOfClassType(S, Fn, LParenLoc, Args, NumArgs, 4833 RParenLoc)); 4834 4835 if (Fn->getType() == Context.UnknownAnyTy) { 4836 ExprResult result = rebuildUnknownAnyFunction(*this, Fn); 4837 if (result.isInvalid()) return ExprError(); 4838 Fn = result.take(); 4839 } 4840 4841 Expr *NakedFn = Fn->IgnoreParens(); 4842 4843 // Determine whether this is a call to an unresolved member function. 4844 if (UnresolvedMemberExpr *MemE = dyn_cast<UnresolvedMemberExpr>(NakedFn)) { 4845 // If lookup was unresolved but not dependent (i.e. didn't find 4846 // an unresolved using declaration), it has to be an overloaded 4847 // function set, which means it must contain either multiple 4848 // declarations (all methods or method templates) or a single 4849 // method template. 4850 assert((MemE->getNumDecls() > 1) || 4851 isa<FunctionTemplateDecl>( 4852 (*MemE->decls_begin())->getUnderlyingDecl())); 4853 (void)MemE; 4854 4855 return BuildCallToMemberFunction(S, Fn, LParenLoc, Args, NumArgs, 4856 RParenLoc); 4857 } 4858 4859 // Determine whether this is a call to a member function. 4860 if (MemberExpr *MemExpr = dyn_cast<MemberExpr>(NakedFn)) { 4861 NamedDecl *MemDecl = MemExpr->getMemberDecl(); 4862 if (isa<CXXMethodDecl>(MemDecl)) 4863 return BuildCallToMemberFunction(S, Fn, LParenLoc, Args, NumArgs, 4864 RParenLoc); 4865 } 4866 4867 // Determine whether this is a call to a pointer-to-member function. 4868 if (BinaryOperator *BO = dyn_cast<BinaryOperator>(NakedFn)) { 4869 if (BO->getOpcode() == BO_PtrMemD || 4870 BO->getOpcode() == BO_PtrMemI) { 4871 if (const FunctionProtoType *FPT 4872 = BO->getType()->getAs<FunctionProtoType>()) { 4873 QualType ResultTy = FPT->getCallResultType(Context); 4874 ExprValueKind VK = Expr::getValueKindForType(FPT->getResultType()); 4875 4876 // Check that the object type isn't more qualified than the 4877 // member function we're calling. 4878 Qualifiers FuncQuals = Qualifiers::fromCVRMask(FPT->getTypeQuals()); 4879 Qualifiers ObjectQuals 4880 = BO->getOpcode() == BO_PtrMemD 4881 ? BO->getLHS()->getType().getQualifiers() 4882 : BO->getLHS()->getType()->getAs<PointerType>() 4883 ->getPointeeType().getQualifiers(); 4884 4885 Qualifiers Difference = ObjectQuals - FuncQuals; 4886 Difference.removeObjCGCAttr(); 4887 Difference.removeAddressSpace(); 4888 if (Difference) { 4889 std::string QualsString = Difference.getAsString(); 4890 Diag(LParenLoc, diag::err_pointer_to_member_call_drops_quals) 4891 << BO->getType().getUnqualifiedType() 4892 << QualsString 4893 << (QualsString.find(' ') == std::string::npos? 1 : 2); 4894 } 4895 4896 CXXMemberCallExpr *TheCall 4897 = new (Context) CXXMemberCallExpr(Context, Fn, Args, 4898 NumArgs, ResultTy, VK, 4899 RParenLoc); 4900 4901 if (CheckCallReturnType(FPT->getResultType(), 4902 BO->getRHS()->getSourceRange().getBegin(), 4903 TheCall, 0)) 4904 return ExprError(); 4905 4906 if (ConvertArgumentsForCall(TheCall, BO, 0, FPT, Args, NumArgs, 4907 RParenLoc)) 4908 return ExprError(); 4909 4910 return MaybeBindToTemporary(TheCall); 4911 } 4912 } 4913 } 4914 } 4915 4916 // If we're directly calling a function, get the appropriate declaration. 4917 // Also, in C++, keep track of whether we should perform argument-dependent 4918 // lookup and whether there were any explicitly-specified template arguments. 4919 4920 Expr *NakedFn = Fn->IgnoreParens(); 4921 if (isa<UnresolvedLookupExpr>(NakedFn)) { 4922 UnresolvedLookupExpr *ULE = cast<UnresolvedLookupExpr>(NakedFn); 4923 return BuildOverloadedCallExpr(S, Fn, ULE, LParenLoc, Args, NumArgs, 4924 RParenLoc, ExecConfig); 4925 } 4926 4927 NamedDecl *NDecl = 0; 4928 if (UnaryOperator *UnOp = dyn_cast<UnaryOperator>(NakedFn)) 4929 if (UnOp->getOpcode() == UO_AddrOf) 4930 NakedFn = UnOp->getSubExpr()->IgnoreParens(); 4931 4932 if (isa<DeclRefExpr>(NakedFn)) 4933 NDecl = cast<DeclRefExpr>(NakedFn)->getDecl(); 4934 4935 return BuildResolvedCallExpr(Fn, NDecl, LParenLoc, Args, NumArgs, RParenLoc, 4936 ExecConfig); 4937} 4938 4939ExprResult 4940Sema::ActOnCUDAExecConfigExpr(Scope *S, SourceLocation LLLLoc, 4941 MultiExprArg execConfig, SourceLocation GGGLoc) { 4942 FunctionDecl *ConfigDecl = Context.getcudaConfigureCallDecl(); 4943 if (!ConfigDecl) 4944 return ExprError(Diag(LLLLoc, diag::err_undeclared_var_use) 4945 << "cudaConfigureCall"); 4946 QualType ConfigQTy = ConfigDecl->getType(); 4947 4948 DeclRefExpr *ConfigDR = new (Context) DeclRefExpr( 4949 ConfigDecl, ConfigQTy, VK_LValue, LLLLoc); 4950 4951 return ActOnCallExpr(S, ConfigDR, LLLLoc, execConfig, GGGLoc, 0); 4952} 4953 4954/// BuildResolvedCallExpr - Build a call to a resolved expression, 4955/// i.e. an expression not of \p OverloadTy. The expression should 4956/// unary-convert to an expression of function-pointer or 4957/// block-pointer type. 4958/// 4959/// \param NDecl the declaration being called, if available 4960ExprResult 4961Sema::BuildResolvedCallExpr(Expr *Fn, NamedDecl *NDecl, 4962 SourceLocation LParenLoc, 4963 Expr **Args, unsigned NumArgs, 4964 SourceLocation RParenLoc, 4965 Expr *Config) { 4966 FunctionDecl *FDecl = dyn_cast_or_null<FunctionDecl>(NDecl); 4967 4968 // Promote the function operand. 4969 ExprResult Result = UsualUnaryConversions(Fn); 4970 if (Result.isInvalid()) 4971 return ExprError(); 4972 Fn = Result.take(); 4973 4974 // Make the call expr early, before semantic checks. This guarantees cleanup 4975 // of arguments and function on error. 4976 CallExpr *TheCall; 4977 if (Config) { 4978 TheCall = new (Context) CUDAKernelCallExpr(Context, Fn, 4979 cast<CallExpr>(Config), 4980 Args, NumArgs, 4981 Context.BoolTy, 4982 VK_RValue, 4983 RParenLoc); 4984 } else { 4985 TheCall = new (Context) CallExpr(Context, Fn, 4986 Args, NumArgs, 4987 Context.BoolTy, 4988 VK_RValue, 4989 RParenLoc); 4990 } 4991 4992 unsigned BuiltinID = (FDecl ? FDecl->getBuiltinID() : 0); 4993 4994 // Bail out early if calling a builtin with custom typechecking. 4995 if (BuiltinID && Context.BuiltinInfo.hasCustomTypechecking(BuiltinID)) 4996 return CheckBuiltinFunctionCall(BuiltinID, TheCall); 4997 4998 retry: 4999 const FunctionType *FuncT; 5000 if (const PointerType *PT = Fn->getType()->getAs<PointerType>()) { 5001 // C99 6.5.2.2p1 - "The expression that denotes the called function shall 5002 // have type pointer to function". 5003 FuncT = PT->getPointeeType()->getAs<FunctionType>(); 5004 if (FuncT == 0) 5005 return ExprError(Diag(LParenLoc, diag::err_typecheck_call_not_function) 5006 << Fn->getType() << Fn->getSourceRange()); 5007 } else if (const BlockPointerType *BPT = 5008 Fn->getType()->getAs<BlockPointerType>()) { 5009 FuncT = BPT->getPointeeType()->castAs<FunctionType>(); 5010 } else { 5011 // Handle calls to expressions of unknown-any type. 5012 if (Fn->getType() == Context.UnknownAnyTy) { 5013 ExprResult rewrite = rebuildUnknownAnyFunction(*this, Fn); 5014 if (rewrite.isInvalid()) return ExprError(); 5015 Fn = rewrite.take(); 5016 TheCall->setCallee(Fn); 5017 goto retry; 5018 } 5019 5020 return ExprError(Diag(LParenLoc, diag::err_typecheck_call_not_function) 5021 << Fn->getType() << Fn->getSourceRange()); 5022 } 5023 5024 if (getLangOptions().CUDA) { 5025 if (Config) { 5026 // CUDA: Kernel calls must be to global functions 5027 if (FDecl && !FDecl->hasAttr<CUDAGlobalAttr>()) 5028 return ExprError(Diag(LParenLoc,diag::err_kern_call_not_global_function) 5029 << FDecl->getName() << Fn->getSourceRange()); 5030 5031 // CUDA: Kernel function must have 'void' return type 5032 if (!FuncT->getResultType()->isVoidType()) 5033 return ExprError(Diag(LParenLoc, diag::err_kern_type_not_void_return) 5034 << Fn->getType() << Fn->getSourceRange()); 5035 } 5036 } 5037 5038 // Check for a valid return type 5039 if (CheckCallReturnType(FuncT->getResultType(), 5040 Fn->getSourceRange().getBegin(), TheCall, 5041 FDecl)) 5042 return ExprError(); 5043 5044 // We know the result type of the call, set it. 5045 TheCall->setType(FuncT->getCallResultType(Context)); 5046 TheCall->setValueKind(Expr::getValueKindForType(FuncT->getResultType())); 5047 5048 if (const FunctionProtoType *Proto = dyn_cast<FunctionProtoType>(FuncT)) { 5049 if (ConvertArgumentsForCall(TheCall, Fn, FDecl, Proto, Args, NumArgs, 5050 RParenLoc)) 5051 return ExprError(); 5052 } else { 5053 assert(isa<FunctionNoProtoType>(FuncT) && "Unknown FunctionType!"); 5054 5055 if (FDecl) { 5056 // Check if we have too few/too many template arguments, based 5057 // on our knowledge of the function definition. 5058 const FunctionDecl *Def = 0; 5059 if (FDecl->hasBody(Def) && NumArgs != Def->param_size()) { 5060 const FunctionProtoType *Proto 5061 = Def->getType()->getAs<FunctionProtoType>(); 5062 if (!Proto || !(Proto->isVariadic() && NumArgs >= Def->param_size())) 5063 Diag(RParenLoc, diag::warn_call_wrong_number_of_arguments) 5064 << (NumArgs > Def->param_size()) << FDecl << Fn->getSourceRange(); 5065 } 5066 5067 // If the function we're calling isn't a function prototype, but we have 5068 // a function prototype from a prior declaratiom, use that prototype. 5069 if (!FDecl->hasPrototype()) 5070 Proto = FDecl->getType()->getAs<FunctionProtoType>(); 5071 } 5072 5073 // Promote the arguments (C99 6.5.2.2p6). 5074 for (unsigned i = 0; i != NumArgs; i++) { 5075 Expr *Arg = Args[i]; 5076 5077 if (Proto && i < Proto->getNumArgs()) { 5078 InitializedEntity Entity 5079 = InitializedEntity::InitializeParameter(Context, 5080 Proto->getArgType(i)); 5081 ExprResult ArgE = PerformCopyInitialization(Entity, 5082 SourceLocation(), 5083 Owned(Arg)); 5084 if (ArgE.isInvalid()) 5085 return true; 5086 5087 Arg = ArgE.takeAs<Expr>(); 5088 5089 } else { 5090 ExprResult ArgE = DefaultArgumentPromotion(Arg); 5091 5092 if (ArgE.isInvalid()) 5093 return true; 5094 5095 Arg = ArgE.takeAs<Expr>(); 5096 } 5097 5098 if (RequireCompleteType(Arg->getSourceRange().getBegin(), 5099 Arg->getType(), 5100 PDiag(diag::err_call_incomplete_argument) 5101 << Arg->getSourceRange())) 5102 return ExprError(); 5103 5104 TheCall->setArg(i, Arg); 5105 } 5106 } 5107 5108 if (CXXMethodDecl *Method = dyn_cast_or_null<CXXMethodDecl>(FDecl)) 5109 if (!Method->isStatic()) 5110 return ExprError(Diag(LParenLoc, diag::err_member_call_without_object) 5111 << Fn->getSourceRange()); 5112 5113 // Check for sentinels 5114 if (NDecl) 5115 DiagnoseSentinelCalls(NDecl, LParenLoc, Args, NumArgs); 5116 5117 // Do special checking on direct calls to functions. 5118 if (FDecl) { 5119 if (CheckFunctionCall(FDecl, TheCall)) 5120 return ExprError(); 5121 5122 if (BuiltinID) 5123 return CheckBuiltinFunctionCall(BuiltinID, TheCall); 5124 } else if (NDecl) { 5125 if (CheckBlockCall(NDecl, TheCall)) 5126 return ExprError(); 5127 } 5128 5129 return MaybeBindToTemporary(TheCall); 5130} 5131 5132ExprResult 5133Sema::ActOnCompoundLiteral(SourceLocation LParenLoc, ParsedType Ty, 5134 SourceLocation RParenLoc, Expr *InitExpr) { 5135 assert((Ty != 0) && "ActOnCompoundLiteral(): missing type"); 5136 // FIXME: put back this assert when initializers are worked out. 5137 //assert((InitExpr != 0) && "ActOnCompoundLiteral(): missing expression"); 5138 5139 TypeSourceInfo *TInfo; 5140 QualType literalType = GetTypeFromParser(Ty, &TInfo); 5141 if (!TInfo) 5142 TInfo = Context.getTrivialTypeSourceInfo(literalType); 5143 5144 return BuildCompoundLiteralExpr(LParenLoc, TInfo, RParenLoc, InitExpr); 5145} 5146 5147ExprResult 5148Sema::BuildCompoundLiteralExpr(SourceLocation LParenLoc, TypeSourceInfo *TInfo, 5149 SourceLocation RParenLoc, Expr *literalExpr) { 5150 QualType literalType = TInfo->getType(); 5151 5152 if (literalType->isArrayType()) { 5153 if (RequireCompleteType(LParenLoc, Context.getBaseElementType(literalType), 5154 PDiag(diag::err_illegal_decl_array_incomplete_type) 5155 << SourceRange(LParenLoc, 5156 literalExpr->getSourceRange().getEnd()))) 5157 return ExprError(); 5158 if (literalType->isVariableArrayType()) 5159 return ExprError(Diag(LParenLoc, diag::err_variable_object_no_init) 5160 << SourceRange(LParenLoc, literalExpr->getSourceRange().getEnd())); 5161 } else if (!literalType->isDependentType() && 5162 RequireCompleteType(LParenLoc, literalType, 5163 PDiag(diag::err_typecheck_decl_incomplete_type) 5164 << SourceRange(LParenLoc, 5165 literalExpr->getSourceRange().getEnd()))) 5166 return ExprError(); 5167 5168 InitializedEntity Entity 5169 = InitializedEntity::InitializeTemporary(literalType); 5170 InitializationKind Kind 5171 = InitializationKind::CreateCast(SourceRange(LParenLoc, RParenLoc), 5172 /*IsCStyleCast=*/true); 5173 InitializationSequence InitSeq(*this, Entity, Kind, &literalExpr, 1); 5174 ExprResult Result = InitSeq.Perform(*this, Entity, Kind, 5175 MultiExprArg(*this, &literalExpr, 1), 5176 &literalType); 5177 if (Result.isInvalid()) 5178 return ExprError(); 5179 literalExpr = Result.get(); 5180 5181 bool isFileScope = getCurFunctionOrMethodDecl() == 0; 5182 if (isFileScope) { // 6.5.2.5p3 5183 if (CheckForConstantInitializer(literalExpr, literalType)) 5184 return ExprError(); 5185 } 5186 5187 // In C, compound literals are l-values for some reason. 5188 ExprValueKind VK = getLangOptions().CPlusPlus ? VK_RValue : VK_LValue; 5189 5190 return Owned(new (Context) CompoundLiteralExpr(LParenLoc, TInfo, literalType, 5191 VK, literalExpr, isFileScope)); 5192} 5193 5194ExprResult 5195Sema::ActOnInitList(SourceLocation LBraceLoc, MultiExprArg initlist, 5196 SourceLocation RBraceLoc) { 5197 unsigned NumInit = initlist.size(); 5198 Expr **InitList = initlist.release(); 5199 5200 // Semantic analysis for initializers is done by ActOnDeclarator() and 5201 // CheckInitializer() - it requires knowledge of the object being intialized. 5202 5203 InitListExpr *E = new (Context) InitListExpr(Context, LBraceLoc, InitList, 5204 NumInit, RBraceLoc); 5205 E->setType(Context.VoidTy); // FIXME: just a place holder for now. 5206 return Owned(E); 5207} 5208 5209/// Prepares for a scalar cast, performing all the necessary stages 5210/// except the final cast and returning the kind required. 5211static CastKind PrepareScalarCast(Sema &S, ExprResult &Src, QualType DestTy) { 5212 // Both Src and Dest are scalar types, i.e. arithmetic or pointer. 5213 // Also, callers should have filtered out the invalid cases with 5214 // pointers. Everything else should be possible. 5215 5216 QualType SrcTy = Src.get()->getType(); 5217 if (S.Context.hasSameUnqualifiedType(SrcTy, DestTy)) 5218 return CK_NoOp; 5219 5220 switch (SrcTy->getScalarTypeKind()) { 5221 case Type::STK_MemberPointer: 5222 llvm_unreachable("member pointer type in C"); 5223 5224 case Type::STK_Pointer: 5225 switch (DestTy->getScalarTypeKind()) { 5226 case Type::STK_Pointer: 5227 return DestTy->isObjCObjectPointerType() ? 5228 CK_AnyPointerToObjCPointerCast : 5229 CK_BitCast; 5230 case Type::STK_Bool: 5231 return CK_PointerToBoolean; 5232 case Type::STK_Integral: 5233 return CK_PointerToIntegral; 5234 case Type::STK_Floating: 5235 case Type::STK_FloatingComplex: 5236 case Type::STK_IntegralComplex: 5237 case Type::STK_MemberPointer: 5238 llvm_unreachable("illegal cast from pointer"); 5239 } 5240 break; 5241 5242 case Type::STK_Bool: // casting from bool is like casting from an integer 5243 case Type::STK_Integral: 5244 switch (DestTy->getScalarTypeKind()) { 5245 case Type::STK_Pointer: 5246 if (Src.get()->isNullPointerConstant(S.Context, Expr::NPC_ValueDependentIsNull)) 5247 return CK_NullToPointer; 5248 return CK_IntegralToPointer; 5249 case Type::STK_Bool: 5250 return CK_IntegralToBoolean; 5251 case Type::STK_Integral: 5252 return CK_IntegralCast; 5253 case Type::STK_Floating: 5254 return CK_IntegralToFloating; 5255 case Type::STK_IntegralComplex: 5256 Src = S.ImpCastExprToType(Src.take(), DestTy->getAs<ComplexType>()->getElementType(), 5257 CK_IntegralCast); 5258 return CK_IntegralRealToComplex; 5259 case Type::STK_FloatingComplex: 5260 Src = S.ImpCastExprToType(Src.take(), DestTy->getAs<ComplexType>()->getElementType(), 5261 CK_IntegralToFloating); 5262 return CK_FloatingRealToComplex; 5263 case Type::STK_MemberPointer: 5264 llvm_unreachable("member pointer type in C"); 5265 } 5266 break; 5267 5268 case Type::STK_Floating: 5269 switch (DestTy->getScalarTypeKind()) { 5270 case Type::STK_Floating: 5271 return CK_FloatingCast; 5272 case Type::STK_Bool: 5273 return CK_FloatingToBoolean; 5274 case Type::STK_Integral: 5275 return CK_FloatingToIntegral; 5276 case Type::STK_FloatingComplex: 5277 Src = S.ImpCastExprToType(Src.take(), DestTy->getAs<ComplexType>()->getElementType(), 5278 CK_FloatingCast); 5279 return CK_FloatingRealToComplex; 5280 case Type::STK_IntegralComplex: 5281 Src = S.ImpCastExprToType(Src.take(), DestTy->getAs<ComplexType>()->getElementType(), 5282 CK_FloatingToIntegral); 5283 return CK_IntegralRealToComplex; 5284 case Type::STK_Pointer: 5285 llvm_unreachable("valid float->pointer cast?"); 5286 case Type::STK_MemberPointer: 5287 llvm_unreachable("member pointer type in C"); 5288 } 5289 break; 5290 5291 case Type::STK_FloatingComplex: 5292 switch (DestTy->getScalarTypeKind()) { 5293 case Type::STK_FloatingComplex: 5294 return CK_FloatingComplexCast; 5295 case Type::STK_IntegralComplex: 5296 return CK_FloatingComplexToIntegralComplex; 5297 case Type::STK_Floating: { 5298 QualType ET = SrcTy->getAs<ComplexType>()->getElementType(); 5299 if (S.Context.hasSameType(ET, DestTy)) 5300 return CK_FloatingComplexToReal; 5301 Src = S.ImpCastExprToType(Src.take(), ET, CK_FloatingComplexToReal); 5302 return CK_FloatingCast; 5303 } 5304 case Type::STK_Bool: 5305 return CK_FloatingComplexToBoolean; 5306 case Type::STK_Integral: 5307 Src = S.ImpCastExprToType(Src.take(), SrcTy->getAs<ComplexType>()->getElementType(), 5308 CK_FloatingComplexToReal); 5309 return CK_FloatingToIntegral; 5310 case Type::STK_Pointer: 5311 llvm_unreachable("valid complex float->pointer cast?"); 5312 case Type::STK_MemberPointer: 5313 llvm_unreachable("member pointer type in C"); 5314 } 5315 break; 5316 5317 case Type::STK_IntegralComplex: 5318 switch (DestTy->getScalarTypeKind()) { 5319 case Type::STK_FloatingComplex: 5320 return CK_IntegralComplexToFloatingComplex; 5321 case Type::STK_IntegralComplex: 5322 return CK_IntegralComplexCast; 5323 case Type::STK_Integral: { 5324 QualType ET = SrcTy->getAs<ComplexType>()->getElementType(); 5325 if (S.Context.hasSameType(ET, DestTy)) 5326 return CK_IntegralComplexToReal; 5327 Src = S.ImpCastExprToType(Src.take(), ET, CK_IntegralComplexToReal); 5328 return CK_IntegralCast; 5329 } 5330 case Type::STK_Bool: 5331 return CK_IntegralComplexToBoolean; 5332 case Type::STK_Floating: 5333 Src = S.ImpCastExprToType(Src.take(), SrcTy->getAs<ComplexType>()->getElementType(), 5334 CK_IntegralComplexToReal); 5335 return CK_IntegralToFloating; 5336 case Type::STK_Pointer: 5337 llvm_unreachable("valid complex int->pointer cast?"); 5338 case Type::STK_MemberPointer: 5339 llvm_unreachable("member pointer type in C"); 5340 } 5341 break; 5342 } 5343 5344 llvm_unreachable("Unhandled scalar cast"); 5345 return CK_BitCast; 5346} 5347 5348/// CheckCastTypes - Check type constraints for casting between types. 5349ExprResult Sema::CheckCastTypes(SourceRange TyR, QualType castType, 5350 Expr *castExpr, CastKind& Kind, ExprValueKind &VK, 5351 CXXCastPath &BasePath, bool FunctionalStyle) { 5352 if (castExpr->getType() == Context.UnknownAnyTy) 5353 return checkUnknownAnyCast(TyR, castType, castExpr, Kind, VK, BasePath); 5354 5355 if (getLangOptions().CPlusPlus) 5356 return CXXCheckCStyleCast(SourceRange(TyR.getBegin(), 5357 castExpr->getLocEnd()), 5358 castType, VK, castExpr, Kind, BasePath, 5359 FunctionalStyle); 5360 5361 assert(!castExpr->getType()->isPlaceholderType()); 5362 5363 // We only support r-value casts in C. 5364 VK = VK_RValue; 5365 5366 // C99 6.5.4p2: the cast type needs to be void or scalar and the expression 5367 // type needs to be scalar. 5368 if (castType->isVoidType()) { 5369 // We don't necessarily do lvalue-to-rvalue conversions on this. 5370 ExprResult castExprRes = IgnoredValueConversions(castExpr); 5371 if (castExprRes.isInvalid()) 5372 return ExprError(); 5373 castExpr = castExprRes.take(); 5374 5375 // Cast to void allows any expr type. 5376 Kind = CK_ToVoid; 5377 return Owned(castExpr); 5378 } 5379 5380 ExprResult castExprRes = DefaultFunctionArrayLvalueConversion(castExpr); 5381 if (castExprRes.isInvalid()) 5382 return ExprError(); 5383 castExpr = castExprRes.take(); 5384 5385 if (RequireCompleteType(TyR.getBegin(), castType, 5386 diag::err_typecheck_cast_to_incomplete)) 5387 return ExprError(); 5388 5389 if (!castType->isScalarType() && !castType->isVectorType()) { 5390 if (Context.hasSameUnqualifiedType(castType, castExpr->getType()) && 5391 (castType->isStructureType() || castType->isUnionType())) { 5392 // GCC struct/union extension: allow cast to self. 5393 // FIXME: Check that the cast destination type is complete. 5394 Diag(TyR.getBegin(), diag::ext_typecheck_cast_nonscalar) 5395 << castType << castExpr->getSourceRange(); 5396 Kind = CK_NoOp; 5397 return Owned(castExpr); 5398 } 5399 5400 if (castType->isUnionType()) { 5401 // GCC cast to union extension 5402 RecordDecl *RD = castType->getAs<RecordType>()->getDecl(); 5403 RecordDecl::field_iterator Field, FieldEnd; 5404 for (Field = RD->field_begin(), FieldEnd = RD->field_end(); 5405 Field != FieldEnd; ++Field) { 5406 if (Context.hasSameUnqualifiedType(Field->getType(), 5407 castExpr->getType()) && 5408 !Field->isUnnamedBitfield()) { 5409 Diag(TyR.getBegin(), diag::ext_typecheck_cast_to_union) 5410 << castExpr->getSourceRange(); 5411 break; 5412 } 5413 } 5414 if (Field == FieldEnd) { 5415 Diag(TyR.getBegin(), diag::err_typecheck_cast_to_union_no_type) 5416 << castExpr->getType() << castExpr->getSourceRange(); 5417 return ExprError(); 5418 } 5419 Kind = CK_ToUnion; 5420 return Owned(castExpr); 5421 } 5422 5423 // Reject any other conversions to non-scalar types. 5424 Diag(TyR.getBegin(), diag::err_typecheck_cond_expect_scalar) 5425 << castType << castExpr->getSourceRange(); 5426 return ExprError(); 5427 } 5428 5429 // The type we're casting to is known to be a scalar or vector. 5430 5431 // Require the operand to be a scalar or vector. 5432 if (!castExpr->getType()->isScalarType() && 5433 !castExpr->getType()->isVectorType()) { 5434 Diag(castExpr->getLocStart(), 5435 diag::err_typecheck_expect_scalar_operand) 5436 << castExpr->getType() << castExpr->getSourceRange(); 5437 return ExprError(); 5438 } 5439 5440 if (castType->isExtVectorType()) 5441 return CheckExtVectorCast(TyR, castType, castExpr, Kind); 5442 5443 if (castType->isVectorType()) { 5444 if (castType->getAs<VectorType>()->getVectorKind() == 5445 VectorType::AltiVecVector && 5446 (castExpr->getType()->isIntegerType() || 5447 castExpr->getType()->isFloatingType())) { 5448 Kind = CK_VectorSplat; 5449 return Owned(castExpr); 5450 } else if (CheckVectorCast(TyR, castType, castExpr->getType(), Kind)) { 5451 return ExprError(); 5452 } else 5453 return Owned(castExpr); 5454 } 5455 if (castExpr->getType()->isVectorType()) { 5456 if (CheckVectorCast(TyR, castExpr->getType(), castType, Kind)) 5457 return ExprError(); 5458 else 5459 return Owned(castExpr); 5460 } 5461 5462 // The source and target types are both scalars, i.e. 5463 // - arithmetic types (fundamental, enum, and complex) 5464 // - all kinds of pointers 5465 // Note that member pointers were filtered out with C++, above. 5466 5467 if (isa<ObjCSelectorExpr>(castExpr)) { 5468 Diag(castExpr->getLocStart(), diag::err_cast_selector_expr); 5469 return ExprError(); 5470 } 5471 5472 // If either type is a pointer, the other type has to be either an 5473 // integer or a pointer. 5474 if (!castType->isArithmeticType()) { 5475 QualType castExprType = castExpr->getType(); 5476 if (!castExprType->isIntegralType(Context) && 5477 castExprType->isArithmeticType()) { 5478 Diag(castExpr->getLocStart(), 5479 diag::err_cast_pointer_from_non_pointer_int) 5480 << castExprType << castExpr->getSourceRange(); 5481 return ExprError(); 5482 } 5483 } else if (!castExpr->getType()->isArithmeticType()) { 5484 if (!castType->isIntegralType(Context) && castType->isArithmeticType()) { 5485 Diag(castExpr->getLocStart(), diag::err_cast_pointer_to_non_pointer_int) 5486 << castType << castExpr->getSourceRange(); 5487 return ExprError(); 5488 } 5489 } 5490 5491 castExprRes = Owned(castExpr); 5492 Kind = PrepareScalarCast(*this, castExprRes, castType); 5493 if (castExprRes.isInvalid()) 5494 return ExprError(); 5495 castExpr = castExprRes.take(); 5496 5497 if (Kind == CK_BitCast) 5498 CheckCastAlign(castExpr, castType, TyR); 5499 5500 return Owned(castExpr); 5501} 5502 5503bool Sema::CheckVectorCast(SourceRange R, QualType VectorTy, QualType Ty, 5504 CastKind &Kind) { 5505 assert(VectorTy->isVectorType() && "Not a vector type!"); 5506 5507 if (Ty->isVectorType() || Ty->isIntegerType()) { 5508 if (Context.getTypeSize(VectorTy) != Context.getTypeSize(Ty)) 5509 return Diag(R.getBegin(), 5510 Ty->isVectorType() ? 5511 diag::err_invalid_conversion_between_vectors : 5512 diag::err_invalid_conversion_between_vector_and_integer) 5513 << VectorTy << Ty << R; 5514 } else 5515 return Diag(R.getBegin(), 5516 diag::err_invalid_conversion_between_vector_and_scalar) 5517 << VectorTy << Ty << R; 5518 5519 Kind = CK_BitCast; 5520 return false; 5521} 5522 5523ExprResult Sema::CheckExtVectorCast(SourceRange R, QualType DestTy, 5524 Expr *CastExpr, CastKind &Kind) { 5525 assert(DestTy->isExtVectorType() && "Not an extended vector type!"); 5526 5527 QualType SrcTy = CastExpr->getType(); 5528 5529 // If SrcTy is a VectorType, the total size must match to explicitly cast to 5530 // an ExtVectorType. 5531 if (SrcTy->isVectorType()) { 5532 if (Context.getTypeSize(DestTy) != Context.getTypeSize(SrcTy)) { 5533 Diag(R.getBegin(),diag::err_invalid_conversion_between_ext_vectors) 5534 << DestTy << SrcTy << R; 5535 return ExprError(); 5536 } 5537 Kind = CK_BitCast; 5538 return Owned(CastExpr); 5539 } 5540 5541 // All non-pointer scalars can be cast to ExtVector type. The appropriate 5542 // conversion will take place first from scalar to elt type, and then 5543 // splat from elt type to vector. 5544 if (SrcTy->isPointerType()) 5545 return Diag(R.getBegin(), 5546 diag::err_invalid_conversion_between_vector_and_scalar) 5547 << DestTy << SrcTy << R; 5548 5549 QualType DestElemTy = DestTy->getAs<ExtVectorType>()->getElementType(); 5550 ExprResult CastExprRes = Owned(CastExpr); 5551 CastKind CK = PrepareScalarCast(*this, CastExprRes, DestElemTy); 5552 if (CastExprRes.isInvalid()) 5553 return ExprError(); 5554 CastExpr = ImpCastExprToType(CastExprRes.take(), DestElemTy, CK).take(); 5555 5556 Kind = CK_VectorSplat; 5557 return Owned(CastExpr); 5558} 5559 5560ExprResult 5561Sema::ActOnCastExpr(Scope *S, SourceLocation LParenLoc, ParsedType Ty, 5562 SourceLocation RParenLoc, Expr *castExpr) { 5563 assert((Ty != 0) && (castExpr != 0) && 5564 "ActOnCastExpr(): missing type or expr"); 5565 5566 TypeSourceInfo *castTInfo; 5567 QualType castType = GetTypeFromParser(Ty, &castTInfo); 5568 if (!castTInfo) 5569 castTInfo = Context.getTrivialTypeSourceInfo(castType); 5570 5571 // If the Expr being casted is a ParenListExpr, handle it specially. 5572 if (isa<ParenListExpr>(castExpr)) 5573 return ActOnCastOfParenListExpr(S, LParenLoc, RParenLoc, castExpr, 5574 castTInfo); 5575 5576 return BuildCStyleCastExpr(LParenLoc, castTInfo, RParenLoc, castExpr); 5577} 5578 5579ExprResult 5580Sema::BuildCStyleCastExpr(SourceLocation LParenLoc, TypeSourceInfo *Ty, 5581 SourceLocation RParenLoc, Expr *castExpr) { 5582 CastKind Kind = CK_Invalid; 5583 ExprValueKind VK = VK_RValue; 5584 CXXCastPath BasePath; 5585 ExprResult CastResult = 5586 CheckCastTypes(SourceRange(LParenLoc, RParenLoc), Ty->getType(), castExpr, 5587 Kind, VK, BasePath); 5588 if (CastResult.isInvalid()) 5589 return ExprError(); 5590 castExpr = CastResult.take(); 5591 5592 return Owned(CStyleCastExpr::Create(Context, 5593 Ty->getType().getNonLValueExprType(Context), 5594 VK, Kind, castExpr, &BasePath, Ty, 5595 LParenLoc, RParenLoc)); 5596} 5597 5598/// This is not an AltiVec-style cast, so turn the ParenListExpr into a sequence 5599/// of comma binary operators. 5600ExprResult 5601Sema::MaybeConvertParenListExprToParenExpr(Scope *S, Expr *expr) { 5602 ParenListExpr *E = dyn_cast<ParenListExpr>(expr); 5603 if (!E) 5604 return Owned(expr); 5605 5606 ExprResult Result(E->getExpr(0)); 5607 5608 for (unsigned i = 1, e = E->getNumExprs(); i != e && !Result.isInvalid(); ++i) 5609 Result = ActOnBinOp(S, E->getExprLoc(), tok::comma, Result.get(), 5610 E->getExpr(i)); 5611 5612 if (Result.isInvalid()) return ExprError(); 5613 5614 return ActOnParenExpr(E->getLParenLoc(), E->getRParenLoc(), Result.get()); 5615} 5616 5617ExprResult 5618Sema::ActOnCastOfParenListExpr(Scope *S, SourceLocation LParenLoc, 5619 SourceLocation RParenLoc, Expr *Op, 5620 TypeSourceInfo *TInfo) { 5621 ParenListExpr *PE = cast<ParenListExpr>(Op); 5622 QualType Ty = TInfo->getType(); 5623 bool isVectorLiteral = false; 5624 5625 // Check for an altivec or OpenCL literal, 5626 // i.e. all the elements are integer constants. 5627 if (getLangOptions().AltiVec && Ty->isVectorType()) { 5628 if (PE->getNumExprs() == 0) { 5629 Diag(PE->getExprLoc(), diag::err_altivec_empty_initializer); 5630 return ExprError(); 5631 } 5632 if (PE->getNumExprs() == 1) { 5633 if (!PE->getExpr(0)->getType()->isVectorType()) 5634 isVectorLiteral = true; 5635 } 5636 else 5637 isVectorLiteral = true; 5638 } 5639 5640 // If this is a vector initializer, '(' type ')' '(' init, ..., init ')' 5641 // then handle it as such. 5642 if (isVectorLiteral) { 5643 llvm::SmallVector<Expr *, 8> initExprs; 5644 // '(...)' form of vector initialization in AltiVec: the number of 5645 // initializers must be one or must match the size of the vector. 5646 // If a single value is specified in the initializer then it will be 5647 // replicated to all the components of the vector 5648 if (Ty->getAs<VectorType>()->getVectorKind() == 5649 VectorType::AltiVecVector) { 5650 unsigned numElems = Ty->getAs<VectorType>()->getNumElements(); 5651 // The number of initializers must be one or must match the size of the 5652 // vector. If a single value is specified in the initializer then it will 5653 // be replicated to all the components of the vector 5654 if (PE->getNumExprs() == 1) { 5655 QualType ElemTy = Ty->getAs<VectorType>()->getElementType(); 5656 ExprResult Literal = Owned(PE->getExpr(0)); 5657 Literal = ImpCastExprToType(Literal.take(), ElemTy, 5658 PrepareScalarCast(*this, Literal, ElemTy)); 5659 return BuildCStyleCastExpr(LParenLoc, TInfo, RParenLoc, Literal.take()); 5660 } 5661 else if (PE->getNumExprs() < numElems) { 5662 Diag(PE->getExprLoc(), 5663 diag::err_incorrect_number_of_vector_initializers); 5664 return ExprError(); 5665 } 5666 else 5667 for (unsigned i = 0, e = PE->getNumExprs(); i != e; ++i) 5668 initExprs.push_back(PE->getExpr(i)); 5669 } 5670 else 5671 for (unsigned i = 0, e = PE->getNumExprs(); i != e; ++i) 5672 initExprs.push_back(PE->getExpr(i)); 5673 5674 // FIXME: This means that pretty-printing the final AST will produce curly 5675 // braces instead of the original commas. 5676 InitListExpr *E = new (Context) InitListExpr(Context, LParenLoc, 5677 &initExprs[0], 5678 initExprs.size(), RParenLoc); 5679 E->setType(Ty); 5680 return BuildCompoundLiteralExpr(LParenLoc, TInfo, RParenLoc, E); 5681 } else { 5682 // This is not an AltiVec-style cast, so turn the ParenListExpr into a 5683 // sequence of BinOp comma operators. 5684 ExprResult Result = MaybeConvertParenListExprToParenExpr(S, Op); 5685 if (Result.isInvalid()) return ExprError(); 5686 return BuildCStyleCastExpr(LParenLoc, TInfo, RParenLoc, Result.take()); 5687 } 5688} 5689 5690ExprResult Sema::ActOnParenOrParenListExpr(SourceLocation L, 5691 SourceLocation R, 5692 MultiExprArg Val, 5693 ParsedType TypeOfCast) { 5694 unsigned nexprs = Val.size(); 5695 Expr **exprs = reinterpret_cast<Expr**>(Val.release()); 5696 assert((exprs != 0) && "ActOnParenOrParenListExpr() missing expr list"); 5697 Expr *expr; 5698 if (nexprs == 1 && TypeOfCast && !TypeIsVectorType(TypeOfCast)) 5699 expr = new (Context) ParenExpr(L, R, exprs[0]); 5700 else 5701 expr = new (Context) ParenListExpr(Context, L, exprs, nexprs, R); 5702 return Owned(expr); 5703} 5704 5705/// \brief Emit a specialized diagnostic when one expression is a null pointer 5706/// constant and the other is not a pointer. 5707bool Sema::DiagnoseConditionalForNull(Expr *LHS, Expr *RHS, 5708 SourceLocation QuestionLoc) { 5709 Expr *NullExpr = LHS; 5710 Expr *NonPointerExpr = RHS; 5711 Expr::NullPointerConstantKind NullKind = 5712 NullExpr->isNullPointerConstant(Context, 5713 Expr::NPC_ValueDependentIsNotNull); 5714 5715 if (NullKind == Expr::NPCK_NotNull) { 5716 NullExpr = RHS; 5717 NonPointerExpr = LHS; 5718 NullKind = 5719 NullExpr->isNullPointerConstant(Context, 5720 Expr::NPC_ValueDependentIsNotNull); 5721 } 5722 5723 if (NullKind == Expr::NPCK_NotNull) 5724 return false; 5725 5726 if (NullKind == Expr::NPCK_ZeroInteger) { 5727 // In this case, check to make sure that we got here from a "NULL" 5728 // string in the source code. 5729 NullExpr = NullExpr->IgnoreParenImpCasts(); 5730 SourceLocation loc = NullExpr->getExprLoc(); 5731 if (!findMacroSpelling(loc, "NULL")) 5732 return false; 5733 } 5734 5735 int DiagType = (NullKind == Expr::NPCK_CXX0X_nullptr); 5736 Diag(QuestionLoc, diag::err_typecheck_cond_incompatible_operands_null) 5737 << NonPointerExpr->getType() << DiagType 5738 << NonPointerExpr->getSourceRange(); 5739 return true; 5740} 5741 5742/// Note that lhs is not null here, even if this is the gnu "x ?: y" extension. 5743/// In that case, lhs = cond. 5744/// C99 6.5.15 5745QualType Sema::CheckConditionalOperands(ExprResult &Cond, ExprResult &LHS, ExprResult &RHS, 5746 ExprValueKind &VK, ExprObjectKind &OK, 5747 SourceLocation QuestionLoc) { 5748 5749 ExprResult lhsResult = CheckPlaceholderExpr(LHS.get()); 5750 if (!lhsResult.isUsable()) return QualType(); 5751 LHS = move(lhsResult); 5752 5753 ExprResult rhsResult = CheckPlaceholderExpr(RHS.get()); 5754 if (!rhsResult.isUsable()) return QualType(); 5755 RHS = move(rhsResult); 5756 5757 // C++ is sufficiently different to merit its own checker. 5758 if (getLangOptions().CPlusPlus) 5759 return CXXCheckConditionalOperands(Cond, LHS, RHS, VK, OK, QuestionLoc); 5760 5761 VK = VK_RValue; 5762 OK = OK_Ordinary; 5763 5764 Cond = UsualUnaryConversions(Cond.take()); 5765 if (Cond.isInvalid()) 5766 return QualType(); 5767 LHS = UsualUnaryConversions(LHS.take()); 5768 if (LHS.isInvalid()) 5769 return QualType(); 5770 RHS = UsualUnaryConversions(RHS.take()); 5771 if (RHS.isInvalid()) 5772 return QualType(); 5773 5774 QualType CondTy = Cond.get()->getType(); 5775 QualType LHSTy = LHS.get()->getType(); 5776 QualType RHSTy = RHS.get()->getType(); 5777 5778 // first, check the condition. 5779 if (!CondTy->isScalarType()) { // C99 6.5.15p2 5780 // OpenCL: Sec 6.3.i says the condition is allowed to be a vector or scalar. 5781 // Throw an error if its not either. 5782 if (getLangOptions().OpenCL) { 5783 if (!CondTy->isVectorType()) { 5784 Diag(Cond.get()->getLocStart(), 5785 diag::err_typecheck_cond_expect_scalar_or_vector) 5786 << CondTy; 5787 return QualType(); 5788 } 5789 } 5790 else { 5791 Diag(Cond.get()->getLocStart(), diag::err_typecheck_cond_expect_scalar) 5792 << CondTy; 5793 return QualType(); 5794 } 5795 } 5796 5797 // Now check the two expressions. 5798 if (LHSTy->isVectorType() || RHSTy->isVectorType()) 5799 return CheckVectorOperands(QuestionLoc, LHS, RHS); 5800 5801 // OpenCL: If the condition is a vector, and both operands are scalar, 5802 // attempt to implicity convert them to the vector type to act like the 5803 // built in select. 5804 if (getLangOptions().OpenCL && CondTy->isVectorType()) { 5805 // Both operands should be of scalar type. 5806 if (!LHSTy->isScalarType()) { 5807 Diag(LHS.get()->getLocStart(), diag::err_typecheck_cond_expect_scalar) 5808 << CondTy; 5809 return QualType(); 5810 } 5811 if (!RHSTy->isScalarType()) { 5812 Diag(RHS.get()->getLocStart(), diag::err_typecheck_cond_expect_scalar) 5813 << CondTy; 5814 return QualType(); 5815 } 5816 // Implicity convert these scalars to the type of the condition. 5817 LHS = ImpCastExprToType(LHS.take(), CondTy, CK_IntegralCast); 5818 RHS = ImpCastExprToType(RHS.take(), CondTy, CK_IntegralCast); 5819 } 5820 5821 // If both operands have arithmetic type, do the usual arithmetic conversions 5822 // to find a common type: C99 6.5.15p3,5. 5823 if (LHSTy->isArithmeticType() && RHSTy->isArithmeticType()) { 5824 UsualArithmeticConversions(LHS, RHS); 5825 if (LHS.isInvalid() || RHS.isInvalid()) 5826 return QualType(); 5827 return LHS.get()->getType(); 5828 } 5829 5830 // If both operands are the same structure or union type, the result is that 5831 // type. 5832 if (const RecordType *LHSRT = LHSTy->getAs<RecordType>()) { // C99 6.5.15p3 5833 if (const RecordType *RHSRT = RHSTy->getAs<RecordType>()) 5834 if (LHSRT->getDecl() == RHSRT->getDecl()) 5835 // "If both the operands have structure or union type, the result has 5836 // that type." This implies that CV qualifiers are dropped. 5837 return LHSTy.getUnqualifiedType(); 5838 // FIXME: Type of conditional expression must be complete in C mode. 5839 } 5840 5841 // C99 6.5.15p5: "If both operands have void type, the result has void type." 5842 // The following || allows only one side to be void (a GCC-ism). 5843 if (LHSTy->isVoidType() || RHSTy->isVoidType()) { 5844 if (!LHSTy->isVoidType()) 5845 Diag(RHS.get()->getLocStart(), diag::ext_typecheck_cond_one_void) 5846 << RHS.get()->getSourceRange(); 5847 if (!RHSTy->isVoidType()) 5848 Diag(LHS.get()->getLocStart(), diag::ext_typecheck_cond_one_void) 5849 << LHS.get()->getSourceRange(); 5850 LHS = ImpCastExprToType(LHS.take(), Context.VoidTy, CK_ToVoid); 5851 RHS = ImpCastExprToType(RHS.take(), Context.VoidTy, CK_ToVoid); 5852 return Context.VoidTy; 5853 } 5854 // C99 6.5.15p6 - "if one operand is a null pointer constant, the result has 5855 // the type of the other operand." 5856 if ((LHSTy->isAnyPointerType() || LHSTy->isBlockPointerType()) && 5857 RHS.get()->isNullPointerConstant(Context, Expr::NPC_ValueDependentIsNull)) { 5858 // promote the null to a pointer. 5859 RHS = ImpCastExprToType(RHS.take(), LHSTy, CK_NullToPointer); 5860 return LHSTy; 5861 } 5862 if ((RHSTy->isAnyPointerType() || RHSTy->isBlockPointerType()) && 5863 LHS.get()->isNullPointerConstant(Context, Expr::NPC_ValueDependentIsNull)) { 5864 LHS = ImpCastExprToType(LHS.take(), RHSTy, CK_NullToPointer); 5865 return RHSTy; 5866 } 5867 5868 // All objective-c pointer type analysis is done here. 5869 QualType compositeType = FindCompositeObjCPointerType(LHS, RHS, 5870 QuestionLoc); 5871 if (LHS.isInvalid() || RHS.isInvalid()) 5872 return QualType(); 5873 if (!compositeType.isNull()) 5874 return compositeType; 5875 5876 5877 // Handle block pointer types. 5878 if (LHSTy->isBlockPointerType() || RHSTy->isBlockPointerType()) { 5879 if (!LHSTy->isBlockPointerType() || !RHSTy->isBlockPointerType()) { 5880 if (LHSTy->isVoidPointerType() || RHSTy->isVoidPointerType()) { 5881 QualType destType = Context.getPointerType(Context.VoidTy); 5882 LHS = ImpCastExprToType(LHS.take(), destType, CK_BitCast); 5883 RHS = ImpCastExprToType(RHS.take(), destType, CK_BitCast); 5884 return destType; 5885 } 5886 Diag(QuestionLoc, diag::err_typecheck_cond_incompatible_operands) 5887 << LHSTy << RHSTy << LHS.get()->getSourceRange() << RHS.get()->getSourceRange(); 5888 return QualType(); 5889 } 5890 // We have 2 block pointer types. 5891 if (Context.getCanonicalType(LHSTy) == Context.getCanonicalType(RHSTy)) { 5892 // Two identical block pointer types are always compatible. 5893 return LHSTy; 5894 } 5895 // The block pointer types aren't identical, continue checking. 5896 QualType lhptee = LHSTy->getAs<BlockPointerType>()->getPointeeType(); 5897 QualType rhptee = RHSTy->getAs<BlockPointerType>()->getPointeeType(); 5898 5899 if (!Context.typesAreCompatible(lhptee.getUnqualifiedType(), 5900 rhptee.getUnqualifiedType())) { 5901 Diag(QuestionLoc, diag::warn_typecheck_cond_incompatible_pointers) 5902 << LHSTy << RHSTy << LHS.get()->getSourceRange() << RHS.get()->getSourceRange(); 5903 // In this situation, we assume void* type. No especially good 5904 // reason, but this is what gcc does, and we do have to pick 5905 // to get a consistent AST. 5906 QualType incompatTy = Context.getPointerType(Context.VoidTy); 5907 LHS = ImpCastExprToType(LHS.take(), incompatTy, CK_BitCast); 5908 RHS = ImpCastExprToType(RHS.take(), incompatTy, CK_BitCast); 5909 return incompatTy; 5910 } 5911 // The block pointer types are compatible. 5912 LHS = ImpCastExprToType(LHS.take(), LHSTy, CK_BitCast); 5913 RHS = ImpCastExprToType(RHS.take(), LHSTy, CK_BitCast); 5914 return LHSTy; 5915 } 5916 5917 // Check constraints for C object pointers types (C99 6.5.15p3,6). 5918 if (LHSTy->isPointerType() && RHSTy->isPointerType()) { 5919 // get the "pointed to" types 5920 QualType lhptee = LHSTy->getAs<PointerType>()->getPointeeType(); 5921 QualType rhptee = RHSTy->getAs<PointerType>()->getPointeeType(); 5922 5923 // ignore qualifiers on void (C99 6.5.15p3, clause 6) 5924 if (lhptee->isVoidType() && rhptee->isIncompleteOrObjectType()) { 5925 // Figure out necessary qualifiers (C99 6.5.15p6) 5926 QualType destPointee 5927 = Context.getQualifiedType(lhptee, rhptee.getQualifiers()); 5928 QualType destType = Context.getPointerType(destPointee); 5929 // Add qualifiers if necessary. 5930 LHS = ImpCastExprToType(LHS.take(), destType, CK_NoOp); 5931 // Promote to void*. 5932 RHS = ImpCastExprToType(RHS.take(), destType, CK_BitCast); 5933 return destType; 5934 } 5935 if (rhptee->isVoidType() && lhptee->isIncompleteOrObjectType()) { 5936 QualType destPointee 5937 = Context.getQualifiedType(rhptee, lhptee.getQualifiers()); 5938 QualType destType = Context.getPointerType(destPointee); 5939 // Add qualifiers if necessary. 5940 RHS = ImpCastExprToType(RHS.take(), destType, CK_NoOp); 5941 // Promote to void*. 5942 LHS = ImpCastExprToType(LHS.take(), destType, CK_BitCast); 5943 return destType; 5944 } 5945 5946 if (Context.getCanonicalType(LHSTy) == Context.getCanonicalType(RHSTy)) { 5947 // Two identical pointer types are always compatible. 5948 return LHSTy; 5949 } 5950 if (!Context.typesAreCompatible(lhptee.getUnqualifiedType(), 5951 rhptee.getUnqualifiedType())) { 5952 Diag(QuestionLoc, diag::warn_typecheck_cond_incompatible_pointers) 5953 << LHSTy << RHSTy << LHS.get()->getSourceRange() << RHS.get()->getSourceRange(); 5954 // In this situation, we assume void* type. No especially good 5955 // reason, but this is what gcc does, and we do have to pick 5956 // to get a consistent AST. 5957 QualType incompatTy = Context.getPointerType(Context.VoidTy); 5958 LHS = ImpCastExprToType(LHS.take(), incompatTy, CK_BitCast); 5959 RHS = ImpCastExprToType(RHS.take(), incompatTy, CK_BitCast); 5960 return incompatTy; 5961 } 5962 // The pointer types are compatible. 5963 // C99 6.5.15p6: If both operands are pointers to compatible types *or* to 5964 // differently qualified versions of compatible types, the result type is 5965 // a pointer to an appropriately qualified version of the *composite* 5966 // type. 5967 // FIXME: Need to calculate the composite type. 5968 // FIXME: Need to add qualifiers 5969 LHS = ImpCastExprToType(LHS.take(), LHSTy, CK_BitCast); 5970 RHS = ImpCastExprToType(RHS.take(), LHSTy, CK_BitCast); 5971 return LHSTy; 5972 } 5973 5974 // GCC compatibility: soften pointer/integer mismatch. Note that 5975 // null pointers have been filtered out by this point. 5976 if (RHSTy->isPointerType() && LHSTy->isIntegerType()) { 5977 Diag(QuestionLoc, diag::warn_typecheck_cond_pointer_integer_mismatch) 5978 << LHSTy << RHSTy << LHS.get()->getSourceRange() << RHS.get()->getSourceRange(); 5979 LHS = ImpCastExprToType(LHS.take(), RHSTy, CK_IntegralToPointer); 5980 return RHSTy; 5981 } 5982 if (LHSTy->isPointerType() && RHSTy->isIntegerType()) { 5983 Diag(QuestionLoc, diag::warn_typecheck_cond_pointer_integer_mismatch) 5984 << LHSTy << RHSTy << LHS.get()->getSourceRange() << RHS.get()->getSourceRange(); 5985 RHS = ImpCastExprToType(RHS.take(), LHSTy, CK_IntegralToPointer); 5986 return LHSTy; 5987 } 5988 5989 // Emit a better diagnostic if one of the expressions is a null pointer 5990 // constant and the other is not a pointer type. In this case, the user most 5991 // likely forgot to take the address of the other expression. 5992 if (DiagnoseConditionalForNull(LHS.get(), RHS.get(), QuestionLoc)) 5993 return QualType(); 5994 5995 // Otherwise, the operands are not compatible. 5996 Diag(QuestionLoc, diag::err_typecheck_cond_incompatible_operands) 5997 << LHSTy << RHSTy << LHS.get()->getSourceRange() << RHS.get()->getSourceRange(); 5998 return QualType(); 5999} 6000 6001/// FindCompositeObjCPointerType - Helper method to find composite type of 6002/// two objective-c pointer types of the two input expressions. 6003QualType Sema::FindCompositeObjCPointerType(ExprResult &LHS, ExprResult &RHS, 6004 SourceLocation QuestionLoc) { 6005 QualType LHSTy = LHS.get()->getType(); 6006 QualType RHSTy = RHS.get()->getType(); 6007 6008 // Handle things like Class and struct objc_class*. Here we case the result 6009 // to the pseudo-builtin, because that will be implicitly cast back to the 6010 // redefinition type if an attempt is made to access its fields. 6011 if (LHSTy->isObjCClassType() && 6012 (Context.hasSameType(RHSTy, Context.ObjCClassRedefinitionType))) { 6013 RHS = ImpCastExprToType(RHS.take(), LHSTy, CK_BitCast); 6014 return LHSTy; 6015 } 6016 if (RHSTy->isObjCClassType() && 6017 (Context.hasSameType(LHSTy, Context.ObjCClassRedefinitionType))) { 6018 LHS = ImpCastExprToType(LHS.take(), RHSTy, CK_BitCast); 6019 return RHSTy; 6020 } 6021 // And the same for struct objc_object* / id 6022 if (LHSTy->isObjCIdType() && 6023 (Context.hasSameType(RHSTy, Context.ObjCIdRedefinitionType))) { 6024 RHS = ImpCastExprToType(RHS.take(), LHSTy, CK_BitCast); 6025 return LHSTy; 6026 } 6027 if (RHSTy->isObjCIdType() && 6028 (Context.hasSameType(LHSTy, Context.ObjCIdRedefinitionType))) { 6029 LHS = ImpCastExprToType(LHS.take(), RHSTy, CK_BitCast); 6030 return RHSTy; 6031 } 6032 // And the same for struct objc_selector* / SEL 6033 if (Context.isObjCSelType(LHSTy) && 6034 (Context.hasSameType(RHSTy, Context.ObjCSelRedefinitionType))) { 6035 RHS = ImpCastExprToType(RHS.take(), LHSTy, CK_BitCast); 6036 return LHSTy; 6037 } 6038 if (Context.isObjCSelType(RHSTy) && 6039 (Context.hasSameType(LHSTy, Context.ObjCSelRedefinitionType))) { 6040 LHS = ImpCastExprToType(LHS.take(), RHSTy, CK_BitCast); 6041 return RHSTy; 6042 } 6043 // Check constraints for Objective-C object pointers types. 6044 if (LHSTy->isObjCObjectPointerType() && RHSTy->isObjCObjectPointerType()) { 6045 6046 if (Context.getCanonicalType(LHSTy) == Context.getCanonicalType(RHSTy)) { 6047 // Two identical object pointer types are always compatible. 6048 return LHSTy; 6049 } 6050 const ObjCObjectPointerType *LHSOPT = LHSTy->getAs<ObjCObjectPointerType>(); 6051 const ObjCObjectPointerType *RHSOPT = RHSTy->getAs<ObjCObjectPointerType>(); 6052 QualType compositeType = LHSTy; 6053 6054 // If both operands are interfaces and either operand can be 6055 // assigned to the other, use that type as the composite 6056 // type. This allows 6057 // xxx ? (A*) a : (B*) b 6058 // where B is a subclass of A. 6059 // 6060 // Additionally, as for assignment, if either type is 'id' 6061 // allow silent coercion. Finally, if the types are 6062 // incompatible then make sure to use 'id' as the composite 6063 // type so the result is acceptable for sending messages to. 6064 6065 // FIXME: Consider unifying with 'areComparableObjCPointerTypes'. 6066 // It could return the composite type. 6067 if (Context.canAssignObjCInterfaces(LHSOPT, RHSOPT)) { 6068 compositeType = RHSOPT->isObjCBuiltinType() ? RHSTy : LHSTy; 6069 } else if (Context.canAssignObjCInterfaces(RHSOPT, LHSOPT)) { 6070 compositeType = LHSOPT->isObjCBuiltinType() ? LHSTy : RHSTy; 6071 } else if ((LHSTy->isObjCQualifiedIdType() || 6072 RHSTy->isObjCQualifiedIdType()) && 6073 Context.ObjCQualifiedIdTypesAreCompatible(LHSTy, RHSTy, true)) { 6074 // Need to handle "id<xx>" explicitly. 6075 // GCC allows qualified id and any Objective-C type to devolve to 6076 // id. Currently localizing to here until clear this should be 6077 // part of ObjCQualifiedIdTypesAreCompatible. 6078 compositeType = Context.getObjCIdType(); 6079 } else if (LHSTy->isObjCIdType() || RHSTy->isObjCIdType()) { 6080 compositeType = Context.getObjCIdType(); 6081 } else if (!(compositeType = 6082 Context.areCommonBaseCompatible(LHSOPT, RHSOPT)).isNull()) 6083 ; 6084 else { 6085 Diag(QuestionLoc, diag::ext_typecheck_cond_incompatible_operands) 6086 << LHSTy << RHSTy 6087 << LHS.get()->getSourceRange() << RHS.get()->getSourceRange(); 6088 QualType incompatTy = Context.getObjCIdType(); 6089 LHS = ImpCastExprToType(LHS.take(), incompatTy, CK_BitCast); 6090 RHS = ImpCastExprToType(RHS.take(), incompatTy, CK_BitCast); 6091 return incompatTy; 6092 } 6093 // The object pointer types are compatible. 6094 LHS = ImpCastExprToType(LHS.take(), compositeType, CK_BitCast); 6095 RHS = ImpCastExprToType(RHS.take(), compositeType, CK_BitCast); 6096 return compositeType; 6097 } 6098 // Check Objective-C object pointer types and 'void *' 6099 if (LHSTy->isVoidPointerType() && RHSTy->isObjCObjectPointerType()) { 6100 QualType lhptee = LHSTy->getAs<PointerType>()->getPointeeType(); 6101 QualType rhptee = RHSTy->getAs<ObjCObjectPointerType>()->getPointeeType(); 6102 QualType destPointee 6103 = Context.getQualifiedType(lhptee, rhptee.getQualifiers()); 6104 QualType destType = Context.getPointerType(destPointee); 6105 // Add qualifiers if necessary. 6106 LHS = ImpCastExprToType(LHS.take(), destType, CK_NoOp); 6107 // Promote to void*. 6108 RHS = ImpCastExprToType(RHS.take(), destType, CK_BitCast); 6109 return destType; 6110 } 6111 if (LHSTy->isObjCObjectPointerType() && RHSTy->isVoidPointerType()) { 6112 QualType lhptee = LHSTy->getAs<ObjCObjectPointerType>()->getPointeeType(); 6113 QualType rhptee = RHSTy->getAs<PointerType>()->getPointeeType(); 6114 QualType destPointee 6115 = Context.getQualifiedType(rhptee, lhptee.getQualifiers()); 6116 QualType destType = Context.getPointerType(destPointee); 6117 // Add qualifiers if necessary. 6118 RHS = ImpCastExprToType(RHS.take(), destType, CK_NoOp); 6119 // Promote to void*. 6120 LHS = ImpCastExprToType(LHS.take(), destType, CK_BitCast); 6121 return destType; 6122 } 6123 return QualType(); 6124} 6125 6126/// ActOnConditionalOp - Parse a ?: operation. Note that 'LHS' may be null 6127/// in the case of a the GNU conditional expr extension. 6128ExprResult Sema::ActOnConditionalOp(SourceLocation QuestionLoc, 6129 SourceLocation ColonLoc, 6130 Expr *CondExpr, Expr *LHSExpr, 6131 Expr *RHSExpr) { 6132 // If this is the gnu "x ?: y" extension, analyze the types as though the LHS 6133 // was the condition. 6134 OpaqueValueExpr *opaqueValue = 0; 6135 Expr *commonExpr = 0; 6136 if (LHSExpr == 0) { 6137 commonExpr = CondExpr; 6138 6139 // We usually want to apply unary conversions *before* saving, except 6140 // in the special case of a C++ l-value conditional. 6141 if (!(getLangOptions().CPlusPlus 6142 && !commonExpr->isTypeDependent() 6143 && commonExpr->getValueKind() == RHSExpr->getValueKind() 6144 && commonExpr->isGLValue() 6145 && commonExpr->isOrdinaryOrBitFieldObject() 6146 && RHSExpr->isOrdinaryOrBitFieldObject() 6147 && Context.hasSameType(commonExpr->getType(), RHSExpr->getType()))) { 6148 ExprResult commonRes = UsualUnaryConversions(commonExpr); 6149 if (commonRes.isInvalid()) 6150 return ExprError(); 6151 commonExpr = commonRes.take(); 6152 } 6153 6154 opaqueValue = new (Context) OpaqueValueExpr(commonExpr->getExprLoc(), 6155 commonExpr->getType(), 6156 commonExpr->getValueKind(), 6157 commonExpr->getObjectKind()); 6158 LHSExpr = CondExpr = opaqueValue; 6159 } 6160 6161 ExprValueKind VK = VK_RValue; 6162 ExprObjectKind OK = OK_Ordinary; 6163 ExprResult Cond = Owned(CondExpr), LHS = Owned(LHSExpr), RHS = Owned(RHSExpr); 6164 QualType result = CheckConditionalOperands(Cond, LHS, RHS, 6165 VK, OK, QuestionLoc); 6166 if (result.isNull() || Cond.isInvalid() || LHS.isInvalid() || 6167 RHS.isInvalid()) 6168 return ExprError(); 6169 6170 if (!commonExpr) 6171 return Owned(new (Context) ConditionalOperator(Cond.take(), QuestionLoc, 6172 LHS.take(), ColonLoc, 6173 RHS.take(), result, VK, OK)); 6174 6175 return Owned(new (Context) 6176 BinaryConditionalOperator(commonExpr, opaqueValue, Cond.take(), LHS.take(), 6177 RHS.take(), QuestionLoc, ColonLoc, result, VK, OK)); 6178} 6179 6180// checkPointerTypesForAssignment - This is a very tricky routine (despite 6181// being closely modeled after the C99 spec:-). The odd characteristic of this 6182// routine is it effectively iqnores the qualifiers on the top level pointee. 6183// This circumvents the usual type rules specified in 6.2.7p1 & 6.7.5.[1-3]. 6184// FIXME: add a couple examples in this comment. 6185static Sema::AssignConvertType 6186checkPointerTypesForAssignment(Sema &S, QualType lhsType, QualType rhsType) { 6187 assert(lhsType.isCanonical() && "LHS not canonicalized!"); 6188 assert(rhsType.isCanonical() && "RHS not canonicalized!"); 6189 6190 // get the "pointed to" type (ignoring qualifiers at the top level) 6191 const Type *lhptee, *rhptee; 6192 Qualifiers lhq, rhq; 6193 llvm::tie(lhptee, lhq) = cast<PointerType>(lhsType)->getPointeeType().split(); 6194 llvm::tie(rhptee, rhq) = cast<PointerType>(rhsType)->getPointeeType().split(); 6195 6196 Sema::AssignConvertType ConvTy = Sema::Compatible; 6197 6198 // C99 6.5.16.1p1: This following citation is common to constraints 6199 // 3 & 4 (below). ...and the type *pointed to* by the left has all the 6200 // qualifiers of the type *pointed to* by the right; 6201 Qualifiers lq; 6202 6203 if (!lhq.compatiblyIncludes(rhq)) { 6204 // Treat address-space mismatches as fatal. TODO: address subspaces 6205 if (lhq.getAddressSpace() != rhq.getAddressSpace()) 6206 ConvTy = Sema::IncompatiblePointerDiscardsQualifiers; 6207 6208 // It's okay to add or remove GC qualifiers when converting to 6209 // and from void*. 6210 else if (lhq.withoutObjCGCAttr().compatiblyIncludes(rhq.withoutObjCGCAttr()) 6211 && (lhptee->isVoidType() || rhptee->isVoidType())) 6212 ; // keep old 6213 6214 // For GCC compatibility, other qualifier mismatches are treated 6215 // as still compatible in C. 6216 else ConvTy = Sema::CompatiblePointerDiscardsQualifiers; 6217 } 6218 6219 // C99 6.5.16.1p1 (constraint 4): If one operand is a pointer to an object or 6220 // incomplete type and the other is a pointer to a qualified or unqualified 6221 // version of void... 6222 if (lhptee->isVoidType()) { 6223 if (rhptee->isIncompleteOrObjectType()) 6224 return ConvTy; 6225 6226 // As an extension, we allow cast to/from void* to function pointer. 6227 assert(rhptee->isFunctionType()); 6228 return Sema::FunctionVoidPointer; 6229 } 6230 6231 if (rhptee->isVoidType()) { 6232 if (lhptee->isIncompleteOrObjectType()) 6233 return ConvTy; 6234 6235 // As an extension, we allow cast to/from void* to function pointer. 6236 assert(lhptee->isFunctionType()); 6237 return Sema::FunctionVoidPointer; 6238 } 6239 6240 // C99 6.5.16.1p1 (constraint 3): both operands are pointers to qualified or 6241 // unqualified versions of compatible types, ... 6242 QualType ltrans = QualType(lhptee, 0), rtrans = QualType(rhptee, 0); 6243 if (!S.Context.typesAreCompatible(ltrans, rtrans)) { 6244 // Check if the pointee types are compatible ignoring the sign. 6245 // We explicitly check for char so that we catch "char" vs 6246 // "unsigned char" on systems where "char" is unsigned. 6247 if (lhptee->isCharType()) 6248 ltrans = S.Context.UnsignedCharTy; 6249 else if (lhptee->hasSignedIntegerRepresentation()) 6250 ltrans = S.Context.getCorrespondingUnsignedType(ltrans); 6251 6252 if (rhptee->isCharType()) 6253 rtrans = S.Context.UnsignedCharTy; 6254 else if (rhptee->hasSignedIntegerRepresentation()) 6255 rtrans = S.Context.getCorrespondingUnsignedType(rtrans); 6256 6257 if (ltrans == rtrans) { 6258 // Types are compatible ignoring the sign. Qualifier incompatibility 6259 // takes priority over sign incompatibility because the sign 6260 // warning can be disabled. 6261 if (ConvTy != Sema::Compatible) 6262 return ConvTy; 6263 6264 return Sema::IncompatiblePointerSign; 6265 } 6266 6267 // If we are a multi-level pointer, it's possible that our issue is simply 6268 // one of qualification - e.g. char ** -> const char ** is not allowed. If 6269 // the eventual target type is the same and the pointers have the same 6270 // level of indirection, this must be the issue. 6271 if (isa<PointerType>(lhptee) && isa<PointerType>(rhptee)) { 6272 do { 6273 lhptee = cast<PointerType>(lhptee)->getPointeeType().getTypePtr(); 6274 rhptee = cast<PointerType>(rhptee)->getPointeeType().getTypePtr(); 6275 } while (isa<PointerType>(lhptee) && isa<PointerType>(rhptee)); 6276 6277 if (lhptee == rhptee) 6278 return Sema::IncompatibleNestedPointerQualifiers; 6279 } 6280 6281 // General pointer incompatibility takes priority over qualifiers. 6282 return Sema::IncompatiblePointer; 6283 } 6284 return ConvTy; 6285} 6286 6287/// checkBlockPointerTypesForAssignment - This routine determines whether two 6288/// block pointer types are compatible or whether a block and normal pointer 6289/// are compatible. It is more restrict than comparing two function pointer 6290// types. 6291static Sema::AssignConvertType 6292checkBlockPointerTypesForAssignment(Sema &S, QualType lhsType, 6293 QualType rhsType) { 6294 assert(lhsType.isCanonical() && "LHS not canonicalized!"); 6295 assert(rhsType.isCanonical() && "RHS not canonicalized!"); 6296 6297 QualType lhptee, rhptee; 6298 6299 // get the "pointed to" type (ignoring qualifiers at the top level) 6300 lhptee = cast<BlockPointerType>(lhsType)->getPointeeType(); 6301 rhptee = cast<BlockPointerType>(rhsType)->getPointeeType(); 6302 6303 // In C++, the types have to match exactly. 6304 if (S.getLangOptions().CPlusPlus) 6305 return Sema::IncompatibleBlockPointer; 6306 6307 Sema::AssignConvertType ConvTy = Sema::Compatible; 6308 6309 // For blocks we enforce that qualifiers are identical. 6310 if (lhptee.getLocalQualifiers() != rhptee.getLocalQualifiers()) 6311 ConvTy = Sema::CompatiblePointerDiscardsQualifiers; 6312 6313 if (!S.Context.typesAreBlockPointerCompatible(lhsType, rhsType)) 6314 return Sema::IncompatibleBlockPointer; 6315 6316 return ConvTy; 6317} 6318 6319/// checkObjCPointerTypesForAssignment - Compares two objective-c pointer types 6320/// for assignment compatibility. 6321static Sema::AssignConvertType 6322checkObjCPointerTypesForAssignment(Sema &S, QualType lhsType, QualType rhsType) { 6323 assert(lhsType.isCanonical() && "LHS was not canonicalized!"); 6324 assert(rhsType.isCanonical() && "RHS was not canonicalized!"); 6325 6326 if (lhsType->isObjCBuiltinType()) { 6327 // Class is not compatible with ObjC object pointers. 6328 if (lhsType->isObjCClassType() && !rhsType->isObjCBuiltinType() && 6329 !rhsType->isObjCQualifiedClassType()) 6330 return Sema::IncompatiblePointer; 6331 return Sema::Compatible; 6332 } 6333 if (rhsType->isObjCBuiltinType()) { 6334 // Class is not compatible with ObjC object pointers. 6335 if (rhsType->isObjCClassType() && !lhsType->isObjCBuiltinType() && 6336 !lhsType->isObjCQualifiedClassType()) 6337 return Sema::IncompatiblePointer; 6338 return Sema::Compatible; 6339 } 6340 QualType lhptee = 6341 lhsType->getAs<ObjCObjectPointerType>()->getPointeeType(); 6342 QualType rhptee = 6343 rhsType->getAs<ObjCObjectPointerType>()->getPointeeType(); 6344 6345 if (!lhptee.isAtLeastAsQualifiedAs(rhptee)) 6346 return Sema::CompatiblePointerDiscardsQualifiers; 6347 6348 if (S.Context.typesAreCompatible(lhsType, rhsType)) 6349 return Sema::Compatible; 6350 if (lhsType->isObjCQualifiedIdType() || rhsType->isObjCQualifiedIdType()) 6351 return Sema::IncompatibleObjCQualifiedId; 6352 return Sema::IncompatiblePointer; 6353} 6354 6355Sema::AssignConvertType 6356Sema::CheckAssignmentConstraints(SourceLocation Loc, 6357 QualType lhsType, QualType rhsType) { 6358 // Fake up an opaque expression. We don't actually care about what 6359 // cast operations are required, so if CheckAssignmentConstraints 6360 // adds casts to this they'll be wasted, but fortunately that doesn't 6361 // usually happen on valid code. 6362 OpaqueValueExpr rhs(Loc, rhsType, VK_RValue); 6363 ExprResult rhsPtr = &rhs; 6364 CastKind K = CK_Invalid; 6365 6366 return CheckAssignmentConstraints(lhsType, rhsPtr, K); 6367} 6368 6369/// CheckAssignmentConstraints (C99 6.5.16) - This routine currently 6370/// has code to accommodate several GCC extensions when type checking 6371/// pointers. Here are some objectionable examples that GCC considers warnings: 6372/// 6373/// int a, *pint; 6374/// short *pshort; 6375/// struct foo *pfoo; 6376/// 6377/// pint = pshort; // warning: assignment from incompatible pointer type 6378/// a = pint; // warning: assignment makes integer from pointer without a cast 6379/// pint = a; // warning: assignment makes pointer from integer without a cast 6380/// pint = pfoo; // warning: assignment from incompatible pointer type 6381/// 6382/// As a result, the code for dealing with pointers is more complex than the 6383/// C99 spec dictates. 6384/// 6385/// Sets 'Kind' for any result kind except Incompatible. 6386Sema::AssignConvertType 6387Sema::CheckAssignmentConstraints(QualType lhsType, ExprResult &rhs, 6388 CastKind &Kind) { 6389 QualType rhsType = rhs.get()->getType(); 6390 6391 // Get canonical types. We're not formatting these types, just comparing 6392 // them. 6393 lhsType = Context.getCanonicalType(lhsType).getUnqualifiedType(); 6394 rhsType = Context.getCanonicalType(rhsType).getUnqualifiedType(); 6395 6396 // Common case: no conversion required. 6397 if (lhsType == rhsType) { 6398 Kind = CK_NoOp; 6399 return Compatible; 6400 } 6401 6402 // If the left-hand side is a reference type, then we are in a 6403 // (rare!) case where we've allowed the use of references in C, 6404 // e.g., as a parameter type in a built-in function. In this case, 6405 // just make sure that the type referenced is compatible with the 6406 // right-hand side type. The caller is responsible for adjusting 6407 // lhsType so that the resulting expression does not have reference 6408 // type. 6409 if (const ReferenceType *lhsTypeRef = lhsType->getAs<ReferenceType>()) { 6410 if (Context.typesAreCompatible(lhsTypeRef->getPointeeType(), rhsType)) { 6411 Kind = CK_LValueBitCast; 6412 return Compatible; 6413 } 6414 return Incompatible; 6415 } 6416 6417 // Allow scalar to ExtVector assignments, and assignments of an ExtVector type 6418 // to the same ExtVector type. 6419 if (lhsType->isExtVectorType()) { 6420 if (rhsType->isExtVectorType()) 6421 return Incompatible; 6422 if (rhsType->isArithmeticType()) { 6423 // CK_VectorSplat does T -> vector T, so first cast to the 6424 // element type. 6425 QualType elType = cast<ExtVectorType>(lhsType)->getElementType(); 6426 if (elType != rhsType) { 6427 Kind = PrepareScalarCast(*this, rhs, elType); 6428 rhs = ImpCastExprToType(rhs.take(), elType, Kind); 6429 } 6430 Kind = CK_VectorSplat; 6431 return Compatible; 6432 } 6433 } 6434 6435 // Conversions to or from vector type. 6436 if (lhsType->isVectorType() || rhsType->isVectorType()) { 6437 if (lhsType->isVectorType() && rhsType->isVectorType()) { 6438 // Allow assignments of an AltiVec vector type to an equivalent GCC 6439 // vector type and vice versa 6440 if (Context.areCompatibleVectorTypes(lhsType, rhsType)) { 6441 Kind = CK_BitCast; 6442 return Compatible; 6443 } 6444 6445 // If we are allowing lax vector conversions, and LHS and RHS are both 6446 // vectors, the total size only needs to be the same. This is a bitcast; 6447 // no bits are changed but the result type is different. 6448 if (getLangOptions().LaxVectorConversions && 6449 (Context.getTypeSize(lhsType) == Context.getTypeSize(rhsType))) { 6450 Kind = CK_BitCast; 6451 return IncompatibleVectors; 6452 } 6453 } 6454 return Incompatible; 6455 } 6456 6457 // Arithmetic conversions. 6458 if (lhsType->isArithmeticType() && rhsType->isArithmeticType() && 6459 !(getLangOptions().CPlusPlus && lhsType->isEnumeralType())) { 6460 Kind = PrepareScalarCast(*this, rhs, lhsType); 6461 return Compatible; 6462 } 6463 6464 // Conversions to normal pointers. 6465 if (const PointerType *lhsPointer = dyn_cast<PointerType>(lhsType)) { 6466 // U* -> T* 6467 if (isa<PointerType>(rhsType)) { 6468 Kind = CK_BitCast; 6469 return checkPointerTypesForAssignment(*this, lhsType, rhsType); 6470 } 6471 6472 // int -> T* 6473 if (rhsType->isIntegerType()) { 6474 Kind = CK_IntegralToPointer; // FIXME: null? 6475 return IntToPointer; 6476 } 6477 6478 // C pointers are not compatible with ObjC object pointers, 6479 // with two exceptions: 6480 if (isa<ObjCObjectPointerType>(rhsType)) { 6481 // - conversions to void* 6482 if (lhsPointer->getPointeeType()->isVoidType()) { 6483 Kind = CK_AnyPointerToObjCPointerCast; 6484 return Compatible; 6485 } 6486 6487 // - conversions from 'Class' to the redefinition type 6488 if (rhsType->isObjCClassType() && 6489 Context.hasSameType(lhsType, Context.ObjCClassRedefinitionType)) { 6490 Kind = CK_BitCast; 6491 return Compatible; 6492 } 6493 6494 Kind = CK_BitCast; 6495 return IncompatiblePointer; 6496 } 6497 6498 // U^ -> void* 6499 if (rhsType->getAs<BlockPointerType>()) { 6500 if (lhsPointer->getPointeeType()->isVoidType()) { 6501 Kind = CK_BitCast; 6502 return Compatible; 6503 } 6504 } 6505 6506 return Incompatible; 6507 } 6508 6509 // Conversions to block pointers. 6510 if (isa<BlockPointerType>(lhsType)) { 6511 // U^ -> T^ 6512 if (rhsType->isBlockPointerType()) { 6513 Kind = CK_AnyPointerToBlockPointerCast; 6514 return checkBlockPointerTypesForAssignment(*this, lhsType, rhsType); 6515 } 6516 6517 // int or null -> T^ 6518 if (rhsType->isIntegerType()) { 6519 Kind = CK_IntegralToPointer; // FIXME: null 6520 return IntToBlockPointer; 6521 } 6522 6523 // id -> T^ 6524 if (getLangOptions().ObjC1 && rhsType->isObjCIdType()) { 6525 Kind = CK_AnyPointerToBlockPointerCast; 6526 return Compatible; 6527 } 6528 6529 // void* -> T^ 6530 if (const PointerType *RHSPT = rhsType->getAs<PointerType>()) 6531 if (RHSPT->getPointeeType()->isVoidType()) { 6532 Kind = CK_AnyPointerToBlockPointerCast; 6533 return Compatible; 6534 } 6535 6536 return Incompatible; 6537 } 6538 6539 // Conversions to Objective-C pointers. 6540 if (isa<ObjCObjectPointerType>(lhsType)) { 6541 // A* -> B* 6542 if (rhsType->isObjCObjectPointerType()) { 6543 Kind = CK_BitCast; 6544 return checkObjCPointerTypesForAssignment(*this, lhsType, rhsType); 6545 } 6546 6547 // int or null -> A* 6548 if (rhsType->isIntegerType()) { 6549 Kind = CK_IntegralToPointer; // FIXME: null 6550 return IntToPointer; 6551 } 6552 6553 // In general, C pointers are not compatible with ObjC object pointers, 6554 // with two exceptions: 6555 if (isa<PointerType>(rhsType)) { 6556 // - conversions from 'void*' 6557 if (rhsType->isVoidPointerType()) { 6558 Kind = CK_AnyPointerToObjCPointerCast; 6559 return Compatible; 6560 } 6561 6562 // - conversions to 'Class' from its redefinition type 6563 if (lhsType->isObjCClassType() && 6564 Context.hasSameType(rhsType, Context.ObjCClassRedefinitionType)) { 6565 Kind = CK_BitCast; 6566 return Compatible; 6567 } 6568 6569 Kind = CK_AnyPointerToObjCPointerCast; 6570 return IncompatiblePointer; 6571 } 6572 6573 // T^ -> A* 6574 if (rhsType->isBlockPointerType()) { 6575 Kind = CK_AnyPointerToObjCPointerCast; 6576 return Compatible; 6577 } 6578 6579 return Incompatible; 6580 } 6581 6582 // Conversions from pointers that are not covered by the above. 6583 if (isa<PointerType>(rhsType)) { 6584 // T* -> _Bool 6585 if (lhsType == Context.BoolTy) { 6586 Kind = CK_PointerToBoolean; 6587 return Compatible; 6588 } 6589 6590 // T* -> int 6591 if (lhsType->isIntegerType()) { 6592 Kind = CK_PointerToIntegral; 6593 return PointerToInt; 6594 } 6595 6596 return Incompatible; 6597 } 6598 6599 // Conversions from Objective-C pointers that are not covered by the above. 6600 if (isa<ObjCObjectPointerType>(rhsType)) { 6601 // T* -> _Bool 6602 if (lhsType == Context.BoolTy) { 6603 Kind = CK_PointerToBoolean; 6604 return Compatible; 6605 } 6606 6607 // T* -> int 6608 if (lhsType->isIntegerType()) { 6609 Kind = CK_PointerToIntegral; 6610 return PointerToInt; 6611 } 6612 6613 return Incompatible; 6614 } 6615 6616 // struct A -> struct B 6617 if (isa<TagType>(lhsType) && isa<TagType>(rhsType)) { 6618 if (Context.typesAreCompatible(lhsType, rhsType)) { 6619 Kind = CK_NoOp; 6620 return Compatible; 6621 } 6622 } 6623 6624 return Incompatible; 6625} 6626 6627/// \brief Constructs a transparent union from an expression that is 6628/// used to initialize the transparent union. 6629static void ConstructTransparentUnion(Sema &S, ASTContext &C, ExprResult &EResult, 6630 QualType UnionType, FieldDecl *Field) { 6631 // Build an initializer list that designates the appropriate member 6632 // of the transparent union. 6633 Expr *E = EResult.take(); 6634 InitListExpr *Initializer = new (C) InitListExpr(C, SourceLocation(), 6635 &E, 1, 6636 SourceLocation()); 6637 Initializer->setType(UnionType); 6638 Initializer->setInitializedFieldInUnion(Field); 6639 6640 // Build a compound literal constructing a value of the transparent 6641 // union type from this initializer list. 6642 TypeSourceInfo *unionTInfo = C.getTrivialTypeSourceInfo(UnionType); 6643 EResult = S.Owned( 6644 new (C) CompoundLiteralExpr(SourceLocation(), unionTInfo, UnionType, 6645 VK_RValue, Initializer, false)); 6646} 6647 6648Sema::AssignConvertType 6649Sema::CheckTransparentUnionArgumentConstraints(QualType ArgType, ExprResult &rExpr) { 6650 QualType FromType = rExpr.get()->getType(); 6651 6652 // If the ArgType is a Union type, we want to handle a potential 6653 // transparent_union GCC extension. 6654 const RecordType *UT = ArgType->getAsUnionType(); 6655 if (!UT || !UT->getDecl()->hasAttr<TransparentUnionAttr>()) 6656 return Incompatible; 6657 6658 // The field to initialize within the transparent union. 6659 RecordDecl *UD = UT->getDecl(); 6660 FieldDecl *InitField = 0; 6661 // It's compatible if the expression matches any of the fields. 6662 for (RecordDecl::field_iterator it = UD->field_begin(), 6663 itend = UD->field_end(); 6664 it != itend; ++it) { 6665 if (it->getType()->isPointerType()) { 6666 // If the transparent union contains a pointer type, we allow: 6667 // 1) void pointer 6668 // 2) null pointer constant 6669 if (FromType->isPointerType()) 6670 if (FromType->getAs<PointerType>()->getPointeeType()->isVoidType()) { 6671 rExpr = ImpCastExprToType(rExpr.take(), it->getType(), CK_BitCast); 6672 InitField = *it; 6673 break; 6674 } 6675 6676 if (rExpr.get()->isNullPointerConstant(Context, 6677 Expr::NPC_ValueDependentIsNull)) { 6678 rExpr = ImpCastExprToType(rExpr.take(), it->getType(), CK_NullToPointer); 6679 InitField = *it; 6680 break; 6681 } 6682 } 6683 6684 CastKind Kind = CK_Invalid; 6685 if (CheckAssignmentConstraints(it->getType(), rExpr, Kind) 6686 == Compatible) { 6687 rExpr = ImpCastExprToType(rExpr.take(), it->getType(), Kind); 6688 InitField = *it; 6689 break; 6690 } 6691 } 6692 6693 if (!InitField) 6694 return Incompatible; 6695 6696 ConstructTransparentUnion(*this, Context, rExpr, ArgType, InitField); 6697 return Compatible; 6698} 6699 6700Sema::AssignConvertType 6701Sema::CheckSingleAssignmentConstraints(QualType lhsType, ExprResult &rExpr) { 6702 if (getLangOptions().CPlusPlus) { 6703 if (!lhsType->isRecordType()) { 6704 // C++ 5.17p3: If the left operand is not of class type, the 6705 // expression is implicitly converted (C++ 4) to the 6706 // cv-unqualified type of the left operand. 6707 ExprResult Res = PerformImplicitConversion(rExpr.get(), 6708 lhsType.getUnqualifiedType(), 6709 AA_Assigning); 6710 if (Res.isInvalid()) 6711 return Incompatible; 6712 rExpr = move(Res); 6713 return Compatible; 6714 } 6715 6716 // FIXME: Currently, we fall through and treat C++ classes like C 6717 // structures. 6718 } 6719 6720 // C99 6.5.16.1p1: the left operand is a pointer and the right is 6721 // a null pointer constant. 6722 if ((lhsType->isPointerType() || 6723 lhsType->isObjCObjectPointerType() || 6724 lhsType->isBlockPointerType()) 6725 && rExpr.get()->isNullPointerConstant(Context, 6726 Expr::NPC_ValueDependentIsNull)) { 6727 rExpr = ImpCastExprToType(rExpr.take(), lhsType, CK_NullToPointer); 6728 return Compatible; 6729 } 6730 6731 // This check seems unnatural, however it is necessary to ensure the proper 6732 // conversion of functions/arrays. If the conversion were done for all 6733 // DeclExpr's (created by ActOnIdExpression), it would mess up the unary 6734 // expressions that suppress this implicit conversion (&, sizeof). 6735 // 6736 // Suppress this for references: C++ 8.5.3p5. 6737 if (!lhsType->isReferenceType()) { 6738 rExpr = DefaultFunctionArrayLvalueConversion(rExpr.take()); 6739 if (rExpr.isInvalid()) 6740 return Incompatible; 6741 } 6742 6743 CastKind Kind = CK_Invalid; 6744 Sema::AssignConvertType result = 6745 CheckAssignmentConstraints(lhsType, rExpr, Kind); 6746 6747 // C99 6.5.16.1p2: The value of the right operand is converted to the 6748 // type of the assignment expression. 6749 // CheckAssignmentConstraints allows the left-hand side to be a reference, 6750 // so that we can use references in built-in functions even in C. 6751 // The getNonReferenceType() call makes sure that the resulting expression 6752 // does not have reference type. 6753 if (result != Incompatible && rExpr.get()->getType() != lhsType) 6754 rExpr = ImpCastExprToType(rExpr.take(), lhsType.getNonLValueExprType(Context), Kind); 6755 return result; 6756} 6757 6758QualType Sema::InvalidOperands(SourceLocation Loc, ExprResult &lex, ExprResult &rex) { 6759 Diag(Loc, diag::err_typecheck_invalid_operands) 6760 << lex.get()->getType() << rex.get()->getType() 6761 << lex.get()->getSourceRange() << rex.get()->getSourceRange(); 6762 return QualType(); 6763} 6764 6765QualType Sema::CheckVectorOperands(SourceLocation Loc, ExprResult &lex, ExprResult &rex) { 6766 // For conversion purposes, we ignore any qualifiers. 6767 // For example, "const float" and "float" are equivalent. 6768 QualType lhsType = 6769 Context.getCanonicalType(lex.get()->getType()).getUnqualifiedType(); 6770 QualType rhsType = 6771 Context.getCanonicalType(rex.get()->getType()).getUnqualifiedType(); 6772 6773 // If the vector types are identical, return. 6774 if (lhsType == rhsType) 6775 return lhsType; 6776 6777 // Handle the case of a vector & extvector type of the same size and element 6778 // type. It would be nice if we only had one vector type someday. 6779 if (getLangOptions().LaxVectorConversions) { 6780 if (const VectorType *LV = lhsType->getAs<VectorType>()) { 6781 if (const VectorType *RV = rhsType->getAs<VectorType>()) { 6782 if (LV->getElementType() == RV->getElementType() && 6783 LV->getNumElements() == RV->getNumElements()) { 6784 if (lhsType->isExtVectorType()) { 6785 rex = ImpCastExprToType(rex.take(), lhsType, CK_BitCast); 6786 return lhsType; 6787 } 6788 6789 lex = ImpCastExprToType(lex.take(), rhsType, CK_BitCast); 6790 return rhsType; 6791 } else if (Context.getTypeSize(lhsType) ==Context.getTypeSize(rhsType)){ 6792 // If we are allowing lax vector conversions, and LHS and RHS are both 6793 // vectors, the total size only needs to be the same. This is a 6794 // bitcast; no bits are changed but the result type is different. 6795 rex = ImpCastExprToType(rex.take(), lhsType, CK_BitCast); 6796 return lhsType; 6797 } 6798 } 6799 } 6800 } 6801 6802 // Handle the case of equivalent AltiVec and GCC vector types 6803 if (lhsType->isVectorType() && rhsType->isVectorType() && 6804 Context.areCompatibleVectorTypes(lhsType, rhsType)) { 6805 lex = ImpCastExprToType(lex.take(), rhsType, CK_BitCast); 6806 return rhsType; 6807 } 6808 6809 // Canonicalize the ExtVector to the LHS, remember if we swapped so we can 6810 // swap back (so that we don't reverse the inputs to a subtract, for instance. 6811 bool swapped = false; 6812 if (rhsType->isExtVectorType()) { 6813 swapped = true; 6814 std::swap(rex, lex); 6815 std::swap(rhsType, lhsType); 6816 } 6817 6818 // Handle the case of an ext vector and scalar. 6819 if (const ExtVectorType *LV = lhsType->getAs<ExtVectorType>()) { 6820 QualType EltTy = LV->getElementType(); 6821 if (EltTy->isIntegralType(Context) && rhsType->isIntegralType(Context)) { 6822 int order = Context.getIntegerTypeOrder(EltTy, rhsType); 6823 if (order > 0) 6824 rex = ImpCastExprToType(rex.take(), EltTy, CK_IntegralCast); 6825 if (order >= 0) { 6826 rex = ImpCastExprToType(rex.take(), lhsType, CK_VectorSplat); 6827 if (swapped) std::swap(rex, lex); 6828 return lhsType; 6829 } 6830 } 6831 if (EltTy->isRealFloatingType() && rhsType->isScalarType() && 6832 rhsType->isRealFloatingType()) { 6833 int order = Context.getFloatingTypeOrder(EltTy, rhsType); 6834 if (order > 0) 6835 rex = ImpCastExprToType(rex.take(), EltTy, CK_FloatingCast); 6836 if (order >= 0) { 6837 rex = ImpCastExprToType(rex.take(), lhsType, CK_VectorSplat); 6838 if (swapped) std::swap(rex, lex); 6839 return lhsType; 6840 } 6841 } 6842 } 6843 6844 // Vectors of different size or scalar and non-ext-vector are errors. 6845 Diag(Loc, diag::err_typecheck_vector_not_convertable) 6846 << lex.get()->getType() << rex.get()->getType() 6847 << lex.get()->getSourceRange() << rex.get()->getSourceRange(); 6848 return QualType(); 6849} 6850 6851QualType Sema::CheckMultiplyDivideOperands( 6852 ExprResult &lex, ExprResult &rex, SourceLocation Loc, bool isCompAssign, bool isDiv) { 6853 if (lex.get()->getType()->isVectorType() || rex.get()->getType()->isVectorType()) 6854 return CheckVectorOperands(Loc, lex, rex); 6855 6856 QualType compType = UsualArithmeticConversions(lex, rex, isCompAssign); 6857 if (lex.isInvalid() || rex.isInvalid()) 6858 return QualType(); 6859 6860 if (!lex.get()->getType()->isArithmeticType() || 6861 !rex.get()->getType()->isArithmeticType()) 6862 return InvalidOperands(Loc, lex, rex); 6863 6864 // Check for division by zero. 6865 if (isDiv && 6866 rex.get()->isNullPointerConstant(Context, Expr::NPC_ValueDependentIsNotNull)) 6867 DiagRuntimeBehavior(Loc, rex.get(), PDiag(diag::warn_division_by_zero) 6868 << rex.get()->getSourceRange()); 6869 6870 return compType; 6871} 6872 6873QualType Sema::CheckRemainderOperands( 6874 ExprResult &lex, ExprResult &rex, SourceLocation Loc, bool isCompAssign) { 6875 if (lex.get()->getType()->isVectorType() || rex.get()->getType()->isVectorType()) { 6876 if (lex.get()->getType()->hasIntegerRepresentation() && 6877 rex.get()->getType()->hasIntegerRepresentation()) 6878 return CheckVectorOperands(Loc, lex, rex); 6879 return InvalidOperands(Loc, lex, rex); 6880 } 6881 6882 QualType compType = UsualArithmeticConversions(lex, rex, isCompAssign); 6883 if (lex.isInvalid() || rex.isInvalid()) 6884 return QualType(); 6885 6886 if (!lex.get()->getType()->isIntegerType() || !rex.get()->getType()->isIntegerType()) 6887 return InvalidOperands(Loc, lex, rex); 6888 6889 // Check for remainder by zero. 6890 if (rex.get()->isNullPointerConstant(Context, Expr::NPC_ValueDependentIsNotNull)) 6891 DiagRuntimeBehavior(Loc, rex.get(), PDiag(diag::warn_remainder_by_zero) 6892 << rex.get()->getSourceRange()); 6893 6894 return compType; 6895} 6896 6897QualType Sema::CheckAdditionOperands( // C99 6.5.6 6898 ExprResult &lex, ExprResult &rex, SourceLocation Loc, QualType* CompLHSTy) { 6899 if (lex.get()->getType()->isVectorType() || rex.get()->getType()->isVectorType()) { 6900 QualType compType = CheckVectorOperands(Loc, lex, rex); 6901 if (CompLHSTy) *CompLHSTy = compType; 6902 return compType; 6903 } 6904 6905 QualType compType = UsualArithmeticConversions(lex, rex, CompLHSTy); 6906 if (lex.isInvalid() || rex.isInvalid()) 6907 return QualType(); 6908 6909 // handle the common case first (both operands are arithmetic). 6910 if (lex.get()->getType()->isArithmeticType() && 6911 rex.get()->getType()->isArithmeticType()) { 6912 if (CompLHSTy) *CompLHSTy = compType; 6913 return compType; 6914 } 6915 6916 // Put any potential pointer into PExp 6917 Expr* PExp = lex.get(), *IExp = rex.get(); 6918 if (IExp->getType()->isAnyPointerType()) 6919 std::swap(PExp, IExp); 6920 6921 if (PExp->getType()->isAnyPointerType()) { 6922 6923 if (IExp->getType()->isIntegerType()) { 6924 QualType PointeeTy = PExp->getType()->getPointeeType(); 6925 6926 // Check for arithmetic on pointers to incomplete types. 6927 if (PointeeTy->isVoidType()) { 6928 if (getLangOptions().CPlusPlus) { 6929 Diag(Loc, diag::err_typecheck_pointer_arith_void_type) 6930 << lex.get()->getSourceRange() << rex.get()->getSourceRange(); 6931 return QualType(); 6932 } 6933 6934 // GNU extension: arithmetic on pointer to void 6935 Diag(Loc, diag::ext_gnu_void_ptr) 6936 << lex.get()->getSourceRange() << rex.get()->getSourceRange(); 6937 } else if (PointeeTy->isFunctionType()) { 6938 if (getLangOptions().CPlusPlus) { 6939 Diag(Loc, diag::err_typecheck_pointer_arith_function_type) 6940 << lex.get()->getType() << lex.get()->getSourceRange(); 6941 return QualType(); 6942 } 6943 6944 // GNU extension: arithmetic on pointer to function 6945 Diag(Loc, diag::ext_gnu_ptr_func_arith) 6946 << lex.get()->getType() << lex.get()->getSourceRange(); 6947 } else { 6948 // Check if we require a complete type. 6949 if (((PExp->getType()->isPointerType() && 6950 !PExp->getType()->isDependentType()) || 6951 PExp->getType()->isObjCObjectPointerType()) && 6952 RequireCompleteType(Loc, PointeeTy, 6953 PDiag(diag::err_typecheck_arithmetic_incomplete_type) 6954 << PExp->getSourceRange() 6955 << PExp->getType())) 6956 return QualType(); 6957 } 6958 // Diagnose bad cases where we step over interface counts. 6959 if (PointeeTy->isObjCObjectType() && LangOpts.ObjCNonFragileABI) { 6960 Diag(Loc, diag::err_arithmetic_nonfragile_interface) 6961 << PointeeTy << PExp->getSourceRange(); 6962 return QualType(); 6963 } 6964 6965 if (CompLHSTy) { 6966 QualType LHSTy = Context.isPromotableBitField(lex.get()); 6967 if (LHSTy.isNull()) { 6968 LHSTy = lex.get()->getType(); 6969 if (LHSTy->isPromotableIntegerType()) 6970 LHSTy = Context.getPromotedIntegerType(LHSTy); 6971 } 6972 *CompLHSTy = LHSTy; 6973 } 6974 return PExp->getType(); 6975 } 6976 } 6977 6978 return InvalidOperands(Loc, lex, rex); 6979} 6980 6981// C99 6.5.6 6982QualType Sema::CheckSubtractionOperands(ExprResult &lex, ExprResult &rex, 6983 SourceLocation Loc, QualType* CompLHSTy) { 6984 if (lex.get()->getType()->isVectorType() || rex.get()->getType()->isVectorType()) { 6985 QualType compType = CheckVectorOperands(Loc, lex, rex); 6986 if (CompLHSTy) *CompLHSTy = compType; 6987 return compType; 6988 } 6989 6990 QualType compType = UsualArithmeticConversions(lex, rex, CompLHSTy); 6991 if (lex.isInvalid() || rex.isInvalid()) 6992 return QualType(); 6993 6994 // Enforce type constraints: C99 6.5.6p3. 6995 6996 // Handle the common case first (both operands are arithmetic). 6997 if (lex.get()->getType()->isArithmeticType() && 6998 rex.get()->getType()->isArithmeticType()) { 6999 if (CompLHSTy) *CompLHSTy = compType; 7000 return compType; 7001 } 7002 7003 // Either ptr - int or ptr - ptr. 7004 if (lex.get()->getType()->isAnyPointerType()) { 7005 QualType lpointee = lex.get()->getType()->getPointeeType(); 7006 7007 // The LHS must be an completely-defined object type. 7008 7009 bool ComplainAboutVoid = false; 7010 Expr *ComplainAboutFunc = 0; 7011 if (lpointee->isVoidType()) { 7012 if (getLangOptions().CPlusPlus) { 7013 Diag(Loc, diag::err_typecheck_pointer_arith_void_type) 7014 << lex.get()->getSourceRange() << rex.get()->getSourceRange(); 7015 return QualType(); 7016 } 7017 7018 // GNU C extension: arithmetic on pointer to void 7019 ComplainAboutVoid = true; 7020 } else if (lpointee->isFunctionType()) { 7021 if (getLangOptions().CPlusPlus) { 7022 Diag(Loc, diag::err_typecheck_pointer_arith_function_type) 7023 << lex.get()->getType() << lex.get()->getSourceRange(); 7024 return QualType(); 7025 } 7026 7027 // GNU C extension: arithmetic on pointer to function 7028 ComplainAboutFunc = lex.get(); 7029 } else if (!lpointee->isDependentType() && 7030 RequireCompleteType(Loc, lpointee, 7031 PDiag(diag::err_typecheck_sub_ptr_object) 7032 << lex.get()->getSourceRange() 7033 << lex.get()->getType())) 7034 return QualType(); 7035 7036 // Diagnose bad cases where we step over interface counts. 7037 if (lpointee->isObjCObjectType() && LangOpts.ObjCNonFragileABI) { 7038 Diag(Loc, diag::err_arithmetic_nonfragile_interface) 7039 << lpointee << lex.get()->getSourceRange(); 7040 return QualType(); 7041 } 7042 7043 // The result type of a pointer-int computation is the pointer type. 7044 if (rex.get()->getType()->isIntegerType()) { 7045 if (ComplainAboutVoid) 7046 Diag(Loc, diag::ext_gnu_void_ptr) 7047 << lex.get()->getSourceRange() << rex.get()->getSourceRange(); 7048 if (ComplainAboutFunc) 7049 Diag(Loc, diag::ext_gnu_ptr_func_arith) 7050 << ComplainAboutFunc->getType() 7051 << ComplainAboutFunc->getSourceRange(); 7052 7053 if (CompLHSTy) *CompLHSTy = lex.get()->getType(); 7054 return lex.get()->getType(); 7055 } 7056 7057 // Handle pointer-pointer subtractions. 7058 if (const PointerType *RHSPTy = rex.get()->getType()->getAs<PointerType>()) { 7059 QualType rpointee = RHSPTy->getPointeeType(); 7060 7061 // RHS must be a completely-type object type. 7062 // Handle the GNU void* extension. 7063 if (rpointee->isVoidType()) { 7064 if (getLangOptions().CPlusPlus) { 7065 Diag(Loc, diag::err_typecheck_pointer_arith_void_type) 7066 << lex.get()->getSourceRange() << rex.get()->getSourceRange(); 7067 return QualType(); 7068 } 7069 7070 ComplainAboutVoid = true; 7071 } else if (rpointee->isFunctionType()) { 7072 if (getLangOptions().CPlusPlus) { 7073 Diag(Loc, diag::err_typecheck_pointer_arith_function_type) 7074 << rex.get()->getType() << rex.get()->getSourceRange(); 7075 return QualType(); 7076 } 7077 7078 // GNU extension: arithmetic on pointer to function 7079 if (!ComplainAboutFunc) 7080 ComplainAboutFunc = rex.get(); 7081 } else if (!rpointee->isDependentType() && 7082 RequireCompleteType(Loc, rpointee, 7083 PDiag(diag::err_typecheck_sub_ptr_object) 7084 << rex.get()->getSourceRange() 7085 << rex.get()->getType())) 7086 return QualType(); 7087 7088 if (getLangOptions().CPlusPlus) { 7089 // Pointee types must be the same: C++ [expr.add] 7090 if (!Context.hasSameUnqualifiedType(lpointee, rpointee)) { 7091 Diag(Loc, diag::err_typecheck_sub_ptr_compatible) 7092 << lex.get()->getType() << rex.get()->getType() 7093 << lex.get()->getSourceRange() << rex.get()->getSourceRange(); 7094 return QualType(); 7095 } 7096 } else { 7097 // Pointee types must be compatible C99 6.5.6p3 7098 if (!Context.typesAreCompatible( 7099 Context.getCanonicalType(lpointee).getUnqualifiedType(), 7100 Context.getCanonicalType(rpointee).getUnqualifiedType())) { 7101 Diag(Loc, diag::err_typecheck_sub_ptr_compatible) 7102 << lex.get()->getType() << rex.get()->getType() 7103 << lex.get()->getSourceRange() << rex.get()->getSourceRange(); 7104 return QualType(); 7105 } 7106 } 7107 7108 if (ComplainAboutVoid) 7109 Diag(Loc, diag::ext_gnu_void_ptr) 7110 << lex.get()->getSourceRange() << rex.get()->getSourceRange(); 7111 if (ComplainAboutFunc) 7112 Diag(Loc, diag::ext_gnu_ptr_func_arith) 7113 << ComplainAboutFunc->getType() 7114 << ComplainAboutFunc->getSourceRange(); 7115 7116 if (CompLHSTy) *CompLHSTy = lex.get()->getType(); 7117 return Context.getPointerDiffType(); 7118 } 7119 } 7120 7121 return InvalidOperands(Loc, lex, rex); 7122} 7123 7124static bool isScopedEnumerationType(QualType T) { 7125 if (const EnumType *ET = dyn_cast<EnumType>(T)) 7126 return ET->getDecl()->isScoped(); 7127 return false; 7128} 7129 7130static void DiagnoseBadShiftValues(Sema& S, ExprResult &lex, ExprResult &rex, 7131 SourceLocation Loc, unsigned Opc, 7132 QualType LHSTy) { 7133 llvm::APSInt Right; 7134 // Check right/shifter operand 7135 if (rex.get()->isValueDependent() || !rex.get()->isIntegerConstantExpr(Right, S.Context)) 7136 return; 7137 7138 if (Right.isNegative()) { 7139 S.DiagRuntimeBehavior(Loc, rex.get(), 7140 S.PDiag(diag::warn_shift_negative) 7141 << rex.get()->getSourceRange()); 7142 return; 7143 } 7144 llvm::APInt LeftBits(Right.getBitWidth(), 7145 S.Context.getTypeSize(lex.get()->getType())); 7146 if (Right.uge(LeftBits)) { 7147 S.DiagRuntimeBehavior(Loc, rex.get(), 7148 S.PDiag(diag::warn_shift_gt_typewidth) 7149 << rex.get()->getSourceRange()); 7150 return; 7151 } 7152 if (Opc != BO_Shl) 7153 return; 7154 7155 // When left shifting an ICE which is signed, we can check for overflow which 7156 // according to C++ has undefined behavior ([expr.shift] 5.8/2). Unsigned 7157 // integers have defined behavior modulo one more than the maximum value 7158 // representable in the result type, so never warn for those. 7159 llvm::APSInt Left; 7160 if (lex.get()->isValueDependent() || !lex.get()->isIntegerConstantExpr(Left, S.Context) || 7161 LHSTy->hasUnsignedIntegerRepresentation()) 7162 return; 7163 llvm::APInt ResultBits = 7164 static_cast<llvm::APInt&>(Right) + Left.getMinSignedBits(); 7165 if (LeftBits.uge(ResultBits)) 7166 return; 7167 llvm::APSInt Result = Left.extend(ResultBits.getLimitedValue()); 7168 Result = Result.shl(Right); 7169 7170 // If we are only missing a sign bit, this is less likely to result in actual 7171 // bugs -- if the result is cast back to an unsigned type, it will have the 7172 // expected value. Thus we place this behind a different warning that can be 7173 // turned off separately if needed. 7174 if (LeftBits == ResultBits - 1) { 7175 S.Diag(Loc, diag::warn_shift_result_overrides_sign_bit) 7176 << Result.toString(10) << LHSTy 7177 << lex.get()->getSourceRange() << rex.get()->getSourceRange(); 7178 return; 7179 } 7180 7181 S.Diag(Loc, diag::warn_shift_result_gt_typewidth) 7182 << Result.toString(10) << Result.getMinSignedBits() << LHSTy 7183 << Left.getBitWidth() << lex.get()->getSourceRange() << rex.get()->getSourceRange(); 7184} 7185 7186// C99 6.5.7 7187QualType Sema::CheckShiftOperands(ExprResult &lex, ExprResult &rex, SourceLocation Loc, 7188 unsigned Opc, bool isCompAssign) { 7189 // C99 6.5.7p2: Each of the operands shall have integer type. 7190 if (!lex.get()->getType()->hasIntegerRepresentation() || 7191 !rex.get()->getType()->hasIntegerRepresentation()) 7192 return InvalidOperands(Loc, lex, rex); 7193 7194 // C++0x: Don't allow scoped enums. FIXME: Use something better than 7195 // hasIntegerRepresentation() above instead of this. 7196 if (isScopedEnumerationType(lex.get()->getType()) || 7197 isScopedEnumerationType(rex.get()->getType())) { 7198 return InvalidOperands(Loc, lex, rex); 7199 } 7200 7201 // Vector shifts promote their scalar inputs to vector type. 7202 if (lex.get()->getType()->isVectorType() || rex.get()->getType()->isVectorType()) 7203 return CheckVectorOperands(Loc, lex, rex); 7204 7205 // Shifts don't perform usual arithmetic conversions, they just do integer 7206 // promotions on each operand. C99 6.5.7p3 7207 7208 // For the LHS, do usual unary conversions, but then reset them away 7209 // if this is a compound assignment. 7210 ExprResult old_lex = lex; 7211 lex = UsualUnaryConversions(lex.take()); 7212 if (lex.isInvalid()) 7213 return QualType(); 7214 QualType LHSTy = lex.get()->getType(); 7215 if (isCompAssign) lex = old_lex; 7216 7217 // The RHS is simpler. 7218 rex = UsualUnaryConversions(rex.take()); 7219 if (rex.isInvalid()) 7220 return QualType(); 7221 7222 // Sanity-check shift operands 7223 DiagnoseBadShiftValues(*this, lex, rex, Loc, Opc, LHSTy); 7224 7225 // "The type of the result is that of the promoted left operand." 7226 return LHSTy; 7227} 7228 7229static bool IsWithinTemplateSpecialization(Decl *D) { 7230 if (DeclContext *DC = D->getDeclContext()) { 7231 if (isa<ClassTemplateSpecializationDecl>(DC)) 7232 return true; 7233 if (FunctionDecl *FD = dyn_cast<FunctionDecl>(DC)) 7234 return FD->isFunctionTemplateSpecialization(); 7235 } 7236 return false; 7237} 7238 7239// C99 6.5.8, C++ [expr.rel] 7240QualType Sema::CheckCompareOperands(ExprResult &lex, ExprResult &rex, SourceLocation Loc, 7241 unsigned OpaqueOpc, bool isRelational) { 7242 BinaryOperatorKind Opc = (BinaryOperatorKind) OpaqueOpc; 7243 7244 // Handle vector comparisons separately. 7245 if (lex.get()->getType()->isVectorType() || rex.get()->getType()->isVectorType()) 7246 return CheckVectorCompareOperands(lex, rex, Loc, isRelational); 7247 7248 QualType lType = lex.get()->getType(); 7249 QualType rType = rex.get()->getType(); 7250 7251 Expr *LHSStripped = lex.get()->IgnoreParenImpCasts(); 7252 Expr *RHSStripped = rex.get()->IgnoreParenImpCasts(); 7253 QualType LHSStrippedType = LHSStripped->getType(); 7254 QualType RHSStrippedType = RHSStripped->getType(); 7255 7256 7257 7258 // Two different enums will raise a warning when compared. 7259 if (const EnumType *LHSEnumType = LHSStrippedType->getAs<EnumType>()) { 7260 if (const EnumType *RHSEnumType = RHSStrippedType->getAs<EnumType>()) { 7261 if (LHSEnumType->getDecl()->getIdentifier() && 7262 RHSEnumType->getDecl()->getIdentifier() && 7263 !Context.hasSameUnqualifiedType(LHSStrippedType, RHSStrippedType)) { 7264 Diag(Loc, diag::warn_comparison_of_mixed_enum_types) 7265 << LHSStrippedType << RHSStrippedType 7266 << lex.get()->getSourceRange() << rex.get()->getSourceRange(); 7267 } 7268 } 7269 } 7270 7271 if (!lType->hasFloatingRepresentation() && 7272 !(lType->isBlockPointerType() && isRelational) && 7273 !lex.get()->getLocStart().isMacroID() && 7274 !rex.get()->getLocStart().isMacroID()) { 7275 // For non-floating point types, check for self-comparisons of the form 7276 // x == x, x != x, x < x, etc. These always evaluate to a constant, and 7277 // often indicate logic errors in the program. 7278 // 7279 // NOTE: Don't warn about comparison expressions resulting from macro 7280 // expansion. Also don't warn about comparisons which are only self 7281 // comparisons within a template specialization. The warnings should catch 7282 // obvious cases in the definition of the template anyways. The idea is to 7283 // warn when the typed comparison operator will always evaluate to the same 7284 // result. 7285 if (DeclRefExpr* DRL = dyn_cast<DeclRefExpr>(LHSStripped)) { 7286 if (DeclRefExpr* DRR = dyn_cast<DeclRefExpr>(RHSStripped)) { 7287 if (DRL->getDecl() == DRR->getDecl() && 7288 !IsWithinTemplateSpecialization(DRL->getDecl())) { 7289 DiagRuntimeBehavior(Loc, 0, PDiag(diag::warn_comparison_always) 7290 << 0 // self- 7291 << (Opc == BO_EQ 7292 || Opc == BO_LE 7293 || Opc == BO_GE)); 7294 } else if (lType->isArrayType() && rType->isArrayType() && 7295 !DRL->getDecl()->getType()->isReferenceType() && 7296 !DRR->getDecl()->getType()->isReferenceType()) { 7297 // what is it always going to eval to? 7298 char always_evals_to; 7299 switch(Opc) { 7300 case BO_EQ: // e.g. array1 == array2 7301 always_evals_to = 0; // false 7302 break; 7303 case BO_NE: // e.g. array1 != array2 7304 always_evals_to = 1; // true 7305 break; 7306 default: 7307 // best we can say is 'a constant' 7308 always_evals_to = 2; // e.g. array1 <= array2 7309 break; 7310 } 7311 DiagRuntimeBehavior(Loc, 0, PDiag(diag::warn_comparison_always) 7312 << 1 // array 7313 << always_evals_to); 7314 } 7315 } 7316 } 7317 7318 if (isa<CastExpr>(LHSStripped)) 7319 LHSStripped = LHSStripped->IgnoreParenCasts(); 7320 if (isa<CastExpr>(RHSStripped)) 7321 RHSStripped = RHSStripped->IgnoreParenCasts(); 7322 7323 // Warn about comparisons against a string constant (unless the other 7324 // operand is null), the user probably wants strcmp. 7325 Expr *literalString = 0; 7326 Expr *literalStringStripped = 0; 7327 if ((isa<StringLiteral>(LHSStripped) || isa<ObjCEncodeExpr>(LHSStripped)) && 7328 !RHSStripped->isNullPointerConstant(Context, 7329 Expr::NPC_ValueDependentIsNull)) { 7330 literalString = lex.get(); 7331 literalStringStripped = LHSStripped; 7332 } else if ((isa<StringLiteral>(RHSStripped) || 7333 isa<ObjCEncodeExpr>(RHSStripped)) && 7334 !LHSStripped->isNullPointerConstant(Context, 7335 Expr::NPC_ValueDependentIsNull)) { 7336 literalString = rex.get(); 7337 literalStringStripped = RHSStripped; 7338 } 7339 7340 if (literalString) { 7341 std::string resultComparison; 7342 switch (Opc) { 7343 case BO_LT: resultComparison = ") < 0"; break; 7344 case BO_GT: resultComparison = ") > 0"; break; 7345 case BO_LE: resultComparison = ") <= 0"; break; 7346 case BO_GE: resultComparison = ") >= 0"; break; 7347 case BO_EQ: resultComparison = ") == 0"; break; 7348 case BO_NE: resultComparison = ") != 0"; break; 7349 default: assert(false && "Invalid comparison operator"); 7350 } 7351 7352 DiagRuntimeBehavior(Loc, 0, 7353 PDiag(diag::warn_stringcompare) 7354 << isa<ObjCEncodeExpr>(literalStringStripped) 7355 << literalString->getSourceRange()); 7356 } 7357 } 7358 7359 // C99 6.5.8p3 / C99 6.5.9p4 7360 if (lex.get()->getType()->isArithmeticType() && rex.get()->getType()->isArithmeticType()) { 7361 UsualArithmeticConversions(lex, rex); 7362 if (lex.isInvalid() || rex.isInvalid()) 7363 return QualType(); 7364 } 7365 else { 7366 lex = UsualUnaryConversions(lex.take()); 7367 if (lex.isInvalid()) 7368 return QualType(); 7369 7370 rex = UsualUnaryConversions(rex.take()); 7371 if (rex.isInvalid()) 7372 return QualType(); 7373 } 7374 7375 lType = lex.get()->getType(); 7376 rType = rex.get()->getType(); 7377 7378 // The result of comparisons is 'bool' in C++, 'int' in C. 7379 QualType ResultTy = Context.getLogicalOperationType(); 7380 7381 if (isRelational) { 7382 if (lType->isRealType() && rType->isRealType()) 7383 return ResultTy; 7384 } else { 7385 // Check for comparisons of floating point operands using != and ==. 7386 if (lType->hasFloatingRepresentation()) 7387 CheckFloatComparison(Loc, lex.get(), rex.get()); 7388 7389 if (lType->isArithmeticType() && rType->isArithmeticType()) 7390 return ResultTy; 7391 } 7392 7393 bool LHSIsNull = lex.get()->isNullPointerConstant(Context, 7394 Expr::NPC_ValueDependentIsNull); 7395 bool RHSIsNull = rex.get()->isNullPointerConstant(Context, 7396 Expr::NPC_ValueDependentIsNull); 7397 7398 // All of the following pointer-related warnings are GCC extensions, except 7399 // when handling null pointer constants. 7400 if (lType->isPointerType() && rType->isPointerType()) { // C99 6.5.8p2 7401 QualType LCanPointeeTy = 7402 Context.getCanonicalType(lType->getAs<PointerType>()->getPointeeType()); 7403 QualType RCanPointeeTy = 7404 Context.getCanonicalType(rType->getAs<PointerType>()->getPointeeType()); 7405 7406 if (getLangOptions().CPlusPlus) { 7407 if (LCanPointeeTy == RCanPointeeTy) 7408 return ResultTy; 7409 if (!isRelational && 7410 (LCanPointeeTy->isVoidType() || RCanPointeeTy->isVoidType())) { 7411 // Valid unless comparison between non-null pointer and function pointer 7412 // This is a gcc extension compatibility comparison. 7413 // In a SFINAE context, we treat this as a hard error to maintain 7414 // conformance with the C++ standard. 7415 if ((LCanPointeeTy->isFunctionType() || RCanPointeeTy->isFunctionType()) 7416 && !LHSIsNull && !RHSIsNull) { 7417 Diag(Loc, 7418 isSFINAEContext()? 7419 diag::err_typecheck_comparison_of_fptr_to_void 7420 : diag::ext_typecheck_comparison_of_fptr_to_void) 7421 << lType << rType << lex.get()->getSourceRange() << rex.get()->getSourceRange(); 7422 7423 if (isSFINAEContext()) 7424 return QualType(); 7425 7426 rex = ImpCastExprToType(rex.take(), lType, CK_BitCast); 7427 return ResultTy; 7428 } 7429 } 7430 7431 // C++ [expr.rel]p2: 7432 // [...] Pointer conversions (4.10) and qualification 7433 // conversions (4.4) are performed on pointer operands (or on 7434 // a pointer operand and a null pointer constant) to bring 7435 // them to their composite pointer type. [...] 7436 // 7437 // C++ [expr.eq]p1 uses the same notion for (in)equality 7438 // comparisons of pointers. 7439 bool NonStandardCompositeType = false; 7440 QualType T = FindCompositePointerType(Loc, lex, rex, 7441 isSFINAEContext()? 0 : &NonStandardCompositeType); 7442 if (T.isNull()) { 7443 Diag(Loc, diag::err_typecheck_comparison_of_distinct_pointers) 7444 << lType << rType << lex.get()->getSourceRange() << rex.get()->getSourceRange(); 7445 return QualType(); 7446 } else if (NonStandardCompositeType) { 7447 Diag(Loc, 7448 diag::ext_typecheck_comparison_of_distinct_pointers_nonstandard) 7449 << lType << rType << T 7450 << lex.get()->getSourceRange() << rex.get()->getSourceRange(); 7451 } 7452 7453 lex = ImpCastExprToType(lex.take(), T, CK_BitCast); 7454 rex = ImpCastExprToType(rex.take(), T, CK_BitCast); 7455 return ResultTy; 7456 } 7457 // C99 6.5.9p2 and C99 6.5.8p2 7458 if (Context.typesAreCompatible(LCanPointeeTy.getUnqualifiedType(), 7459 RCanPointeeTy.getUnqualifiedType())) { 7460 // Valid unless a relational comparison of function pointers 7461 if (isRelational && LCanPointeeTy->isFunctionType()) { 7462 Diag(Loc, diag::ext_typecheck_ordered_comparison_of_function_pointers) 7463 << lType << rType << lex.get()->getSourceRange() << rex.get()->getSourceRange(); 7464 } 7465 } else if (!isRelational && 7466 (LCanPointeeTy->isVoidType() || RCanPointeeTy->isVoidType())) { 7467 // Valid unless comparison between non-null pointer and function pointer 7468 if ((LCanPointeeTy->isFunctionType() || RCanPointeeTy->isFunctionType()) 7469 && !LHSIsNull && !RHSIsNull) { 7470 Diag(Loc, diag::ext_typecheck_comparison_of_fptr_to_void) 7471 << lType << rType << lex.get()->getSourceRange() << rex.get()->getSourceRange(); 7472 } 7473 } else { 7474 // Invalid 7475 Diag(Loc, diag::ext_typecheck_comparison_of_distinct_pointers) 7476 << lType << rType << lex.get()->getSourceRange() << rex.get()->getSourceRange(); 7477 } 7478 if (LCanPointeeTy != RCanPointeeTy) { 7479 if (LHSIsNull && !RHSIsNull) 7480 lex = ImpCastExprToType(lex.take(), rType, CK_BitCast); 7481 else 7482 rex = ImpCastExprToType(rex.take(), lType, CK_BitCast); 7483 } 7484 return ResultTy; 7485 } 7486 7487 if (getLangOptions().CPlusPlus) { 7488 // Comparison of nullptr_t with itself. 7489 if (lType->isNullPtrType() && rType->isNullPtrType()) 7490 return ResultTy; 7491 7492 // Comparison of pointers with null pointer constants and equality 7493 // comparisons of member pointers to null pointer constants. 7494 if (RHSIsNull && 7495 ((lType->isPointerType() || lType->isNullPtrType()) || 7496 (!isRelational && lType->isMemberPointerType()))) { 7497 rex = ImpCastExprToType(rex.take(), lType, 7498 lType->isMemberPointerType() 7499 ? CK_NullToMemberPointer 7500 : CK_NullToPointer); 7501 return ResultTy; 7502 } 7503 if (LHSIsNull && 7504 ((rType->isPointerType() || rType->isNullPtrType()) || 7505 (!isRelational && rType->isMemberPointerType()))) { 7506 lex = ImpCastExprToType(lex.take(), rType, 7507 rType->isMemberPointerType() 7508 ? CK_NullToMemberPointer 7509 : CK_NullToPointer); 7510 return ResultTy; 7511 } 7512 7513 // Comparison of member pointers. 7514 if (!isRelational && 7515 lType->isMemberPointerType() && rType->isMemberPointerType()) { 7516 // C++ [expr.eq]p2: 7517 // In addition, pointers to members can be compared, or a pointer to 7518 // member and a null pointer constant. Pointer to member conversions 7519 // (4.11) and qualification conversions (4.4) are performed to bring 7520 // them to a common type. If one operand is a null pointer constant, 7521 // the common type is the type of the other operand. Otherwise, the 7522 // common type is a pointer to member type similar (4.4) to the type 7523 // of one of the operands, with a cv-qualification signature (4.4) 7524 // that is the union of the cv-qualification signatures of the operand 7525 // types. 7526 bool NonStandardCompositeType = false; 7527 QualType T = FindCompositePointerType(Loc, lex, rex, 7528 isSFINAEContext()? 0 : &NonStandardCompositeType); 7529 if (T.isNull()) { 7530 Diag(Loc, diag::err_typecheck_comparison_of_distinct_pointers) 7531 << lType << rType << lex.get()->getSourceRange() << rex.get()->getSourceRange(); 7532 return QualType(); 7533 } else if (NonStandardCompositeType) { 7534 Diag(Loc, 7535 diag::ext_typecheck_comparison_of_distinct_pointers_nonstandard) 7536 << lType << rType << T 7537 << lex.get()->getSourceRange() << rex.get()->getSourceRange(); 7538 } 7539 7540 lex = ImpCastExprToType(lex.take(), T, CK_BitCast); 7541 rex = ImpCastExprToType(rex.take(), T, CK_BitCast); 7542 return ResultTy; 7543 } 7544 7545 // Handle scoped enumeration types specifically, since they don't promote 7546 // to integers. 7547 if (lex.get()->getType()->isEnumeralType() && 7548 Context.hasSameUnqualifiedType(lex.get()->getType(), rex.get()->getType())) 7549 return ResultTy; 7550 } 7551 7552 // Handle block pointer types. 7553 if (!isRelational && lType->isBlockPointerType() && rType->isBlockPointerType()) { 7554 QualType lpointee = lType->getAs<BlockPointerType>()->getPointeeType(); 7555 QualType rpointee = rType->getAs<BlockPointerType>()->getPointeeType(); 7556 7557 if (!LHSIsNull && !RHSIsNull && 7558 !Context.typesAreCompatible(lpointee, rpointee)) { 7559 Diag(Loc, diag::err_typecheck_comparison_of_distinct_blocks) 7560 << lType << rType << lex.get()->getSourceRange() << rex.get()->getSourceRange(); 7561 } 7562 rex = ImpCastExprToType(rex.take(), lType, CK_BitCast); 7563 return ResultTy; 7564 } 7565 7566 // Allow block pointers to be compared with null pointer constants. 7567 if (!isRelational 7568 && ((lType->isBlockPointerType() && rType->isPointerType()) 7569 || (lType->isPointerType() && rType->isBlockPointerType()))) { 7570 if (!LHSIsNull && !RHSIsNull) { 7571 if (!((rType->isPointerType() && rType->castAs<PointerType>() 7572 ->getPointeeType()->isVoidType()) 7573 || (lType->isPointerType() && lType->castAs<PointerType>() 7574 ->getPointeeType()->isVoidType()))) 7575 Diag(Loc, diag::err_typecheck_comparison_of_distinct_blocks) 7576 << lType << rType << lex.get()->getSourceRange() << rex.get()->getSourceRange(); 7577 } 7578 if (LHSIsNull && !RHSIsNull) 7579 lex = ImpCastExprToType(lex.take(), rType, CK_BitCast); 7580 else 7581 rex = ImpCastExprToType(rex.take(), lType, CK_BitCast); 7582 return ResultTy; 7583 } 7584 7585 if (lType->isObjCObjectPointerType() || rType->isObjCObjectPointerType()) { 7586 const PointerType *LPT = lType->getAs<PointerType>(); 7587 const PointerType *RPT = rType->getAs<PointerType>(); 7588 if (LPT || RPT) { 7589 bool LPtrToVoid = LPT ? LPT->getPointeeType()->isVoidType() : false; 7590 bool RPtrToVoid = RPT ? RPT->getPointeeType()->isVoidType() : false; 7591 7592 if (!LPtrToVoid && !RPtrToVoid && 7593 !Context.typesAreCompatible(lType, rType)) { 7594 Diag(Loc, diag::ext_typecheck_comparison_of_distinct_pointers) 7595 << lType << rType << lex.get()->getSourceRange() << rex.get()->getSourceRange(); 7596 } 7597 if (LHSIsNull && !RHSIsNull) 7598 lex = ImpCastExprToType(lex.take(), rType, CK_BitCast); 7599 else 7600 rex = ImpCastExprToType(rex.take(), lType, CK_BitCast); 7601 return ResultTy; 7602 } 7603 if (lType->isObjCObjectPointerType() && rType->isObjCObjectPointerType()) { 7604 if (!Context.areComparableObjCPointerTypes(lType, rType)) 7605 Diag(Loc, diag::ext_typecheck_comparison_of_distinct_pointers) 7606 << lType << rType << lex.get()->getSourceRange() << rex.get()->getSourceRange(); 7607 if (LHSIsNull && !RHSIsNull) 7608 lex = ImpCastExprToType(lex.take(), rType, CK_BitCast); 7609 else 7610 rex = ImpCastExprToType(rex.take(), lType, CK_BitCast); 7611 return ResultTy; 7612 } 7613 } 7614 if ((lType->isAnyPointerType() && rType->isIntegerType()) || 7615 (lType->isIntegerType() && rType->isAnyPointerType())) { 7616 unsigned DiagID = 0; 7617 bool isError = false; 7618 if ((LHSIsNull && lType->isIntegerType()) || 7619 (RHSIsNull && rType->isIntegerType())) { 7620 if (isRelational && !getLangOptions().CPlusPlus) 7621 DiagID = diag::ext_typecheck_ordered_comparison_of_pointer_and_zero; 7622 } else if (isRelational && !getLangOptions().CPlusPlus) 7623 DiagID = diag::ext_typecheck_ordered_comparison_of_pointer_integer; 7624 else if (getLangOptions().CPlusPlus) { 7625 DiagID = diag::err_typecheck_comparison_of_pointer_integer; 7626 isError = true; 7627 } else 7628 DiagID = diag::ext_typecheck_comparison_of_pointer_integer; 7629 7630 if (DiagID) { 7631 Diag(Loc, DiagID) 7632 << lType << rType << lex.get()->getSourceRange() << rex.get()->getSourceRange(); 7633 if (isError) 7634 return QualType(); 7635 } 7636 7637 if (lType->isIntegerType()) 7638 lex = ImpCastExprToType(lex.take(), rType, 7639 LHSIsNull ? CK_NullToPointer : CK_IntegralToPointer); 7640 else 7641 rex = ImpCastExprToType(rex.take(), lType, 7642 RHSIsNull ? CK_NullToPointer : CK_IntegralToPointer); 7643 return ResultTy; 7644 } 7645 7646 // Handle block pointers. 7647 if (!isRelational && RHSIsNull 7648 && lType->isBlockPointerType() && rType->isIntegerType()) { 7649 rex = ImpCastExprToType(rex.take(), lType, CK_NullToPointer); 7650 return ResultTy; 7651 } 7652 if (!isRelational && LHSIsNull 7653 && lType->isIntegerType() && rType->isBlockPointerType()) { 7654 lex = ImpCastExprToType(lex.take(), rType, CK_NullToPointer); 7655 return ResultTy; 7656 } 7657 7658 return InvalidOperands(Loc, lex, rex); 7659} 7660 7661/// CheckVectorCompareOperands - vector comparisons are a clang extension that 7662/// operates on extended vector types. Instead of producing an IntTy result, 7663/// like a scalar comparison, a vector comparison produces a vector of integer 7664/// types. 7665QualType Sema::CheckVectorCompareOperands(ExprResult &lex, ExprResult &rex, 7666 SourceLocation Loc, 7667 bool isRelational) { 7668 // Check to make sure we're operating on vectors of the same type and width, 7669 // Allowing one side to be a scalar of element type. 7670 QualType vType = CheckVectorOperands(Loc, lex, rex); 7671 if (vType.isNull()) 7672 return vType; 7673 7674 QualType lType = lex.get()->getType(); 7675 QualType rType = rex.get()->getType(); 7676 7677 // If AltiVec, the comparison results in a numeric type, i.e. 7678 // bool for C++, int for C 7679 if (vType->getAs<VectorType>()->getVectorKind() == VectorType::AltiVecVector) 7680 return Context.getLogicalOperationType(); 7681 7682 // For non-floating point types, check for self-comparisons of the form 7683 // x == x, x != x, x < x, etc. These always evaluate to a constant, and 7684 // often indicate logic errors in the program. 7685 if (!lType->hasFloatingRepresentation()) { 7686 if (DeclRefExpr* DRL = dyn_cast<DeclRefExpr>(lex.get()->IgnoreParens())) 7687 if (DeclRefExpr* DRR = dyn_cast<DeclRefExpr>(rex.get()->IgnoreParens())) 7688 if (DRL->getDecl() == DRR->getDecl()) 7689 DiagRuntimeBehavior(Loc, 0, 7690 PDiag(diag::warn_comparison_always) 7691 << 0 // self- 7692 << 2 // "a constant" 7693 ); 7694 } 7695 7696 // Check for comparisons of floating point operands using != and ==. 7697 if (!isRelational && lType->hasFloatingRepresentation()) { 7698 assert (rType->hasFloatingRepresentation()); 7699 CheckFloatComparison(Loc, lex.get(), rex.get()); 7700 } 7701 7702 // Return the type for the comparison, which is the same as vector type for 7703 // integer vectors, or an integer type of identical size and number of 7704 // elements for floating point vectors. 7705 if (lType->hasIntegerRepresentation()) 7706 return lType; 7707 7708 const VectorType *VTy = lType->getAs<VectorType>(); 7709 unsigned TypeSize = Context.getTypeSize(VTy->getElementType()); 7710 if (TypeSize == Context.getTypeSize(Context.IntTy)) 7711 return Context.getExtVectorType(Context.IntTy, VTy->getNumElements()); 7712 if (TypeSize == Context.getTypeSize(Context.LongTy)) 7713 return Context.getExtVectorType(Context.LongTy, VTy->getNumElements()); 7714 7715 assert(TypeSize == Context.getTypeSize(Context.LongLongTy) && 7716 "Unhandled vector element size in vector compare"); 7717 return Context.getExtVectorType(Context.LongLongTy, VTy->getNumElements()); 7718} 7719 7720inline QualType Sema::CheckBitwiseOperands( 7721 ExprResult &lex, ExprResult &rex, SourceLocation Loc, bool isCompAssign) { 7722 if (lex.get()->getType()->isVectorType() || rex.get()->getType()->isVectorType()) { 7723 if (lex.get()->getType()->hasIntegerRepresentation() && 7724 rex.get()->getType()->hasIntegerRepresentation()) 7725 return CheckVectorOperands(Loc, lex, rex); 7726 7727 return InvalidOperands(Loc, lex, rex); 7728 } 7729 7730 ExprResult lexResult = Owned(lex), rexResult = Owned(rex); 7731 QualType compType = UsualArithmeticConversions(lexResult, rexResult, isCompAssign); 7732 if (lexResult.isInvalid() || rexResult.isInvalid()) 7733 return QualType(); 7734 lex = lexResult.take(); 7735 rex = rexResult.take(); 7736 7737 if (lex.get()->getType()->isIntegralOrUnscopedEnumerationType() && 7738 rex.get()->getType()->isIntegralOrUnscopedEnumerationType()) 7739 return compType; 7740 return InvalidOperands(Loc, lex, rex); 7741} 7742 7743inline QualType Sema::CheckLogicalOperands( // C99 6.5.[13,14] 7744 ExprResult &lex, ExprResult &rex, SourceLocation Loc, unsigned Opc) { 7745 7746 // Diagnose cases where the user write a logical and/or but probably meant a 7747 // bitwise one. We do this when the LHS is a non-bool integer and the RHS 7748 // is a constant. 7749 if (lex.get()->getType()->isIntegerType() && !lex.get()->getType()->isBooleanType() && 7750 rex.get()->getType()->isIntegerType() && !rex.get()->isValueDependent() && 7751 // Don't warn in macros. 7752 !Loc.isMacroID()) { 7753 // If the RHS can be constant folded, and if it constant folds to something 7754 // that isn't 0 or 1 (which indicate a potential logical operation that 7755 // happened to fold to true/false) then warn. 7756 Expr::EvalResult Result; 7757 if (rex.get()->Evaluate(Result, Context) && !Result.HasSideEffects && 7758 Result.Val.getInt() != 0 && Result.Val.getInt() != 1) { 7759 Diag(Loc, diag::warn_logical_instead_of_bitwise) 7760 << rex.get()->getSourceRange() 7761 << (Opc == BO_LAnd ? "&&" : "||") 7762 << (Opc == BO_LAnd ? "&" : "|"); 7763 } 7764 } 7765 7766 if (!Context.getLangOptions().CPlusPlus) { 7767 lex = UsualUnaryConversions(lex.take()); 7768 if (lex.isInvalid()) 7769 return QualType(); 7770 7771 rex = UsualUnaryConversions(rex.take()); 7772 if (rex.isInvalid()) 7773 return QualType(); 7774 7775 if (!lex.get()->getType()->isScalarType() || !rex.get()->getType()->isScalarType()) 7776 return InvalidOperands(Loc, lex, rex); 7777 7778 return Context.IntTy; 7779 } 7780 7781 // The following is safe because we only use this method for 7782 // non-overloadable operands. 7783 7784 // C++ [expr.log.and]p1 7785 // C++ [expr.log.or]p1 7786 // The operands are both contextually converted to type bool. 7787 ExprResult lexRes = PerformContextuallyConvertToBool(lex.get()); 7788 if (lexRes.isInvalid()) 7789 return InvalidOperands(Loc, lex, rex); 7790 lex = move(lexRes); 7791 7792 ExprResult rexRes = PerformContextuallyConvertToBool(rex.get()); 7793 if (rexRes.isInvalid()) 7794 return InvalidOperands(Loc, lex, rex); 7795 rex = move(rexRes); 7796 7797 // C++ [expr.log.and]p2 7798 // C++ [expr.log.or]p2 7799 // The result is a bool. 7800 return Context.BoolTy; 7801} 7802 7803/// IsReadonlyProperty - Verify that otherwise a valid l-value expression 7804/// is a read-only property; return true if so. A readonly property expression 7805/// depends on various declarations and thus must be treated specially. 7806/// 7807static bool IsReadonlyProperty(Expr *E, Sema &S) { 7808 if (E->getStmtClass() == Expr::ObjCPropertyRefExprClass) { 7809 const ObjCPropertyRefExpr* PropExpr = cast<ObjCPropertyRefExpr>(E); 7810 if (PropExpr->isImplicitProperty()) return false; 7811 7812 ObjCPropertyDecl *PDecl = PropExpr->getExplicitProperty(); 7813 QualType BaseType = PropExpr->isSuperReceiver() ? 7814 PropExpr->getSuperReceiverType() : 7815 PropExpr->getBase()->getType(); 7816 7817 if (const ObjCObjectPointerType *OPT = 7818 BaseType->getAsObjCInterfacePointerType()) 7819 if (ObjCInterfaceDecl *IFace = OPT->getInterfaceDecl()) 7820 if (S.isPropertyReadonly(PDecl, IFace)) 7821 return true; 7822 } 7823 return false; 7824} 7825 7826static bool IsConstProperty(Expr *E, Sema &S) { 7827 if (E->getStmtClass() == Expr::ObjCPropertyRefExprClass) { 7828 const ObjCPropertyRefExpr* PropExpr = cast<ObjCPropertyRefExpr>(E); 7829 if (PropExpr->isImplicitProperty()) return false; 7830 7831 ObjCPropertyDecl *PDecl = PropExpr->getExplicitProperty(); 7832 QualType T = PDecl->getType(); 7833 if (T->isReferenceType()) 7834 T = T->getAs<ReferenceType>()->getPointeeType(); 7835 CanQualType CT = S.Context.getCanonicalType(T); 7836 return CT.isConstQualified(); 7837 } 7838 return false; 7839} 7840 7841static bool IsReadonlyMessage(Expr *E, Sema &S) { 7842 if (E->getStmtClass() != Expr::MemberExprClass) 7843 return false; 7844 const MemberExpr *ME = cast<MemberExpr>(E); 7845 NamedDecl *Member = ME->getMemberDecl(); 7846 if (isa<FieldDecl>(Member)) { 7847 Expr *Base = ME->getBase()->IgnoreParenImpCasts(); 7848 if (Base->getStmtClass() != Expr::ObjCMessageExprClass) 7849 return false; 7850 return cast<ObjCMessageExpr>(Base)->getMethodDecl() != 0; 7851 } 7852 return false; 7853} 7854 7855/// CheckForModifiableLvalue - Verify that E is a modifiable lvalue. If not, 7856/// emit an error and return true. If so, return false. 7857static bool CheckForModifiableLvalue(Expr *E, SourceLocation Loc, Sema &S) { 7858 SourceLocation OrigLoc = Loc; 7859 Expr::isModifiableLvalueResult IsLV = E->isModifiableLvalue(S.Context, 7860 &Loc); 7861 if (IsLV == Expr::MLV_Valid && IsReadonlyProperty(E, S)) 7862 IsLV = Expr::MLV_ReadonlyProperty; 7863 else if (Expr::MLV_ConstQualified && IsConstProperty(E, S)) 7864 IsLV = Expr::MLV_Valid; 7865 else if (IsLV == Expr::MLV_ClassTemporary && IsReadonlyMessage(E, S)) 7866 IsLV = Expr::MLV_InvalidMessageExpression; 7867 if (IsLV == Expr::MLV_Valid) 7868 return false; 7869 7870 unsigned Diag = 0; 7871 bool NeedType = false; 7872 switch (IsLV) { // C99 6.5.16p2 7873 case Expr::MLV_ConstQualified: Diag = diag::err_typecheck_assign_const; break; 7874 case Expr::MLV_ArrayType: 7875 Diag = diag::err_typecheck_array_not_modifiable_lvalue; 7876 NeedType = true; 7877 break; 7878 case Expr::MLV_NotObjectType: 7879 Diag = diag::err_typecheck_non_object_not_modifiable_lvalue; 7880 NeedType = true; 7881 break; 7882 case Expr::MLV_LValueCast: 7883 Diag = diag::err_typecheck_lvalue_casts_not_supported; 7884 break; 7885 case Expr::MLV_Valid: 7886 llvm_unreachable("did not take early return for MLV_Valid"); 7887 case Expr::MLV_InvalidExpression: 7888 case Expr::MLV_MemberFunction: 7889 case Expr::MLV_ClassTemporary: 7890 Diag = diag::err_typecheck_expression_not_modifiable_lvalue; 7891 break; 7892 case Expr::MLV_IncompleteType: 7893 case Expr::MLV_IncompleteVoidType: 7894 return S.RequireCompleteType(Loc, E->getType(), 7895 S.PDiag(diag::err_typecheck_incomplete_type_not_modifiable_lvalue) 7896 << E->getSourceRange()); 7897 case Expr::MLV_DuplicateVectorComponents: 7898 Diag = diag::err_typecheck_duplicate_vector_components_not_mlvalue; 7899 break; 7900 case Expr::MLV_NotBlockQualified: 7901 Diag = diag::err_block_decl_ref_not_modifiable_lvalue; 7902 break; 7903 case Expr::MLV_ReadonlyProperty: 7904 Diag = diag::error_readonly_property_assignment; 7905 break; 7906 case Expr::MLV_NoSetterProperty: 7907 Diag = diag::error_nosetter_property_assignment; 7908 break; 7909 case Expr::MLV_InvalidMessageExpression: 7910 Diag = diag::error_readonly_message_assignment; 7911 break; 7912 case Expr::MLV_SubObjCPropertySetting: 7913 Diag = diag::error_no_subobject_property_setting; 7914 break; 7915 } 7916 7917 SourceRange Assign; 7918 if (Loc != OrigLoc) 7919 Assign = SourceRange(OrigLoc, OrigLoc); 7920 if (NeedType) 7921 S.Diag(Loc, Diag) << E->getType() << E->getSourceRange() << Assign; 7922 else 7923 S.Diag(Loc, Diag) << E->getSourceRange() << Assign; 7924 return true; 7925} 7926 7927 7928 7929// C99 6.5.16.1 7930QualType Sema::CheckAssignmentOperands(Expr *LHS, ExprResult &RHS, 7931 SourceLocation Loc, 7932 QualType CompoundType) { 7933 // Verify that LHS is a modifiable lvalue, and emit error if not. 7934 if (CheckForModifiableLvalue(LHS, Loc, *this)) 7935 return QualType(); 7936 7937 QualType LHSType = LHS->getType(); 7938 QualType RHSType = CompoundType.isNull() ? RHS.get()->getType() : CompoundType; 7939 AssignConvertType ConvTy; 7940 if (CompoundType.isNull()) { 7941 QualType LHSTy(LHSType); 7942 // Simple assignment "x = y". 7943 if (LHS->getObjectKind() == OK_ObjCProperty) { 7944 ExprResult LHSResult = Owned(LHS); 7945 ConvertPropertyForLValue(LHSResult, RHS, LHSTy); 7946 if (LHSResult.isInvalid()) 7947 return QualType(); 7948 LHS = LHSResult.take(); 7949 } 7950 ConvTy = CheckSingleAssignmentConstraints(LHSTy, RHS); 7951 if (RHS.isInvalid()) 7952 return QualType(); 7953 // Special case of NSObject attributes on c-style pointer types. 7954 if (ConvTy == IncompatiblePointer && 7955 ((Context.isObjCNSObjectType(LHSType) && 7956 RHSType->isObjCObjectPointerType()) || 7957 (Context.isObjCNSObjectType(RHSType) && 7958 LHSType->isObjCObjectPointerType()))) 7959 ConvTy = Compatible; 7960 7961 if (ConvTy == Compatible && 7962 getLangOptions().ObjCNonFragileABI && 7963 LHSType->isObjCObjectType()) 7964 Diag(Loc, diag::err_assignment_requires_nonfragile_object) 7965 << LHSType; 7966 7967 // If the RHS is a unary plus or minus, check to see if they = and + are 7968 // right next to each other. If so, the user may have typo'd "x =+ 4" 7969 // instead of "x += 4". 7970 Expr *RHSCheck = RHS.get(); 7971 if (ImplicitCastExpr *ICE = dyn_cast<ImplicitCastExpr>(RHSCheck)) 7972 RHSCheck = ICE->getSubExpr(); 7973 if (UnaryOperator *UO = dyn_cast<UnaryOperator>(RHSCheck)) { 7974 if ((UO->getOpcode() == UO_Plus || 7975 UO->getOpcode() == UO_Minus) && 7976 Loc.isFileID() && UO->getOperatorLoc().isFileID() && 7977 // Only if the two operators are exactly adjacent. 7978 Loc.getFileLocWithOffset(1) == UO->getOperatorLoc() && 7979 // And there is a space or other character before the subexpr of the 7980 // unary +/-. We don't want to warn on "x=-1". 7981 Loc.getFileLocWithOffset(2) != UO->getSubExpr()->getLocStart() && 7982 UO->getSubExpr()->getLocStart().isFileID()) { 7983 Diag(Loc, diag::warn_not_compound_assign) 7984 << (UO->getOpcode() == UO_Plus ? "+" : "-") 7985 << SourceRange(UO->getOperatorLoc(), UO->getOperatorLoc()); 7986 } 7987 } 7988 } else { 7989 // Compound assignment "x += y" 7990 ConvTy = CheckAssignmentConstraints(Loc, LHSType, RHSType); 7991 } 7992 7993 if (DiagnoseAssignmentResult(ConvTy, Loc, LHSType, RHSType, 7994 RHS.get(), AA_Assigning)) 7995 return QualType(); 7996 7997 7998 // Check to see if the destination operand is a dereferenced null pointer. If 7999 // so, and if not volatile-qualified, this is undefined behavior that the 8000 // optimizer will delete, so warn about it. People sometimes try to use this 8001 // to get a deterministic trap and are surprised by clang's behavior. This 8002 // only handles the pattern "*null = whatever", which is a very syntactic 8003 // check. 8004 if (UnaryOperator *UO = dyn_cast<UnaryOperator>(LHS->IgnoreParenCasts())) 8005 if (UO->getOpcode() == UO_Deref && 8006 UO->getSubExpr()->IgnoreParenCasts()-> 8007 isNullPointerConstant(Context, Expr::NPC_ValueDependentIsNotNull) && 8008 !UO->getType().isVolatileQualified()) { 8009 DiagRuntimeBehavior(UO->getOperatorLoc(), UO, 8010 PDiag(diag::warn_indirection_through_null) 8011 << UO->getSubExpr()->getSourceRange()); 8012 DiagRuntimeBehavior(UO->getOperatorLoc(), UO, 8013 PDiag(diag::note_indirection_through_null)); 8014 } 8015 8016 // Check for trivial buffer overflows. 8017 CheckArrayAccess(LHS->IgnoreParenCasts()); 8018 8019 // C99 6.5.16p3: The type of an assignment expression is the type of the 8020 // left operand unless the left operand has qualified type, in which case 8021 // it is the unqualified version of the type of the left operand. 8022 // C99 6.5.16.1p2: In simple assignment, the value of the right operand 8023 // is converted to the type of the assignment expression (above). 8024 // C++ 5.17p1: the type of the assignment expression is that of its left 8025 // operand. 8026 return (getLangOptions().CPlusPlus 8027 ? LHSType : LHSType.getUnqualifiedType()); 8028} 8029 8030// C99 6.5.17 8031static QualType CheckCommaOperands(Sema &S, ExprResult &LHS, ExprResult &RHS, 8032 SourceLocation Loc) { 8033 S.DiagnoseUnusedExprResult(LHS.get()); 8034 8035 LHS = S.CheckPlaceholderExpr(LHS.take()); 8036 RHS = S.CheckPlaceholderExpr(RHS.take()); 8037 if (LHS.isInvalid() || RHS.isInvalid()) 8038 return QualType(); 8039 8040 // C's comma performs lvalue conversion (C99 6.3.2.1) on both its 8041 // operands, but not unary promotions. 8042 // C++'s comma does not do any conversions at all (C++ [expr.comma]p1). 8043 8044 // So we treat the LHS as a ignored value, and in C++ we allow the 8045 // containing site to determine what should be done with the RHS. 8046 LHS = S.IgnoredValueConversions(LHS.take()); 8047 if (LHS.isInvalid()) 8048 return QualType(); 8049 8050 if (!S.getLangOptions().CPlusPlus) { 8051 RHS = S.DefaultFunctionArrayLvalueConversion(RHS.take()); 8052 if (RHS.isInvalid()) 8053 return QualType(); 8054 if (!RHS.get()->getType()->isVoidType()) 8055 S.RequireCompleteType(Loc, RHS.get()->getType(), diag::err_incomplete_type); 8056 } 8057 8058 return RHS.get()->getType(); 8059} 8060 8061/// CheckIncrementDecrementOperand - unlike most "Check" methods, this routine 8062/// doesn't need to call UsualUnaryConversions or UsualArithmeticConversions. 8063static QualType CheckIncrementDecrementOperand(Sema &S, Expr *Op, 8064 ExprValueKind &VK, 8065 SourceLocation OpLoc, 8066 bool isInc, bool isPrefix) { 8067 if (Op->isTypeDependent()) 8068 return S.Context.DependentTy; 8069 8070 QualType ResType = Op->getType(); 8071 assert(!ResType.isNull() && "no type for increment/decrement expression"); 8072 8073 if (S.getLangOptions().CPlusPlus && ResType->isBooleanType()) { 8074 // Decrement of bool is not allowed. 8075 if (!isInc) { 8076 S.Diag(OpLoc, diag::err_decrement_bool) << Op->getSourceRange(); 8077 return QualType(); 8078 } 8079 // Increment of bool sets it to true, but is deprecated. 8080 S.Diag(OpLoc, diag::warn_increment_bool) << Op->getSourceRange(); 8081 } else if (ResType->isRealType()) { 8082 // OK! 8083 } else if (ResType->isAnyPointerType()) { 8084 QualType PointeeTy = ResType->getPointeeType(); 8085 8086 // C99 6.5.2.4p2, 6.5.6p2 8087 if (PointeeTy->isVoidType()) { 8088 if (S.getLangOptions().CPlusPlus) { 8089 S.Diag(OpLoc, diag::err_typecheck_pointer_arith_void_type) 8090 << Op->getSourceRange(); 8091 return QualType(); 8092 } 8093 8094 // Pointer to void is a GNU extension in C. 8095 S.Diag(OpLoc, diag::ext_gnu_void_ptr) << Op->getSourceRange(); 8096 } else if (PointeeTy->isFunctionType()) { 8097 if (S.getLangOptions().CPlusPlus) { 8098 S.Diag(OpLoc, diag::err_typecheck_pointer_arith_function_type) 8099 << Op->getType() << Op->getSourceRange(); 8100 return QualType(); 8101 } 8102 8103 S.Diag(OpLoc, diag::ext_gnu_ptr_func_arith) 8104 << ResType << Op->getSourceRange(); 8105 } else if (S.RequireCompleteType(OpLoc, PointeeTy, 8106 S.PDiag(diag::err_typecheck_arithmetic_incomplete_type) 8107 << Op->getSourceRange() 8108 << ResType)) 8109 return QualType(); 8110 // Diagnose bad cases where we step over interface counts. 8111 else if (PointeeTy->isObjCObjectType() && S.LangOpts.ObjCNonFragileABI) { 8112 S.Diag(OpLoc, diag::err_arithmetic_nonfragile_interface) 8113 << PointeeTy << Op->getSourceRange(); 8114 return QualType(); 8115 } 8116 } else if (ResType->isAnyComplexType()) { 8117 // C99 does not support ++/-- on complex types, we allow as an extension. 8118 S.Diag(OpLoc, diag::ext_integer_increment_complex) 8119 << ResType << Op->getSourceRange(); 8120 } else if (ResType->isPlaceholderType()) { 8121 ExprResult PR = S.CheckPlaceholderExpr(Op); 8122 if (PR.isInvalid()) return QualType(); 8123 return CheckIncrementDecrementOperand(S, PR.take(), VK, OpLoc, 8124 isInc, isPrefix); 8125 } else if (S.getLangOptions().AltiVec && ResType->isVectorType()) { 8126 // OK! ( C/C++ Language Extensions for CBEA(Version 2.6) 10.3 ) 8127 } else { 8128 S.Diag(OpLoc, diag::err_typecheck_illegal_increment_decrement) 8129 << ResType << int(isInc) << Op->getSourceRange(); 8130 return QualType(); 8131 } 8132 // At this point, we know we have a real, complex or pointer type. 8133 // Now make sure the operand is a modifiable lvalue. 8134 if (CheckForModifiableLvalue(Op, OpLoc, S)) 8135 return QualType(); 8136 // In C++, a prefix increment is the same type as the operand. Otherwise 8137 // (in C or with postfix), the increment is the unqualified type of the 8138 // operand. 8139 if (isPrefix && S.getLangOptions().CPlusPlus) { 8140 VK = VK_LValue; 8141 return ResType; 8142 } else { 8143 VK = VK_RValue; 8144 return ResType.getUnqualifiedType(); 8145 } 8146} 8147 8148ExprResult Sema::ConvertPropertyForRValue(Expr *E) { 8149 assert(E->getValueKind() == VK_LValue && 8150 E->getObjectKind() == OK_ObjCProperty); 8151 const ObjCPropertyRefExpr *PRE = E->getObjCProperty(); 8152 8153 ExprValueKind VK = VK_RValue; 8154 if (PRE->isImplicitProperty()) { 8155 if (const ObjCMethodDecl *GetterMethod = 8156 PRE->getImplicitPropertyGetter()) { 8157 QualType Result = GetterMethod->getResultType(); 8158 VK = Expr::getValueKindForType(Result); 8159 } 8160 else { 8161 Diag(PRE->getLocation(), diag::err_getter_not_found) 8162 << PRE->getBase()->getType(); 8163 } 8164 } 8165 8166 E = ImplicitCastExpr::Create(Context, E->getType(), CK_GetObjCProperty, 8167 E, 0, VK); 8168 8169 ExprResult Result = MaybeBindToTemporary(E); 8170 if (!Result.isInvalid()) 8171 E = Result.take(); 8172 8173 return Owned(E); 8174} 8175 8176void Sema::ConvertPropertyForLValue(ExprResult &LHS, ExprResult &RHS, QualType &LHSTy) { 8177 assert(LHS.get()->getValueKind() == VK_LValue && 8178 LHS.get()->getObjectKind() == OK_ObjCProperty); 8179 const ObjCPropertyRefExpr *PropRef = LHS.get()->getObjCProperty(); 8180 8181 if (PropRef->isImplicitProperty()) { 8182 // If using property-dot syntax notation for assignment, and there is a 8183 // setter, RHS expression is being passed to the setter argument. So, 8184 // type conversion (and comparison) is RHS to setter's argument type. 8185 if (const ObjCMethodDecl *SetterMD = PropRef->getImplicitPropertySetter()) { 8186 ObjCMethodDecl::param_iterator P = SetterMD->param_begin(); 8187 LHSTy = (*P)->getType(); 8188 8189 // Otherwise, if the getter returns an l-value, just call that. 8190 } else { 8191 QualType Result = PropRef->getImplicitPropertyGetter()->getResultType(); 8192 ExprValueKind VK = Expr::getValueKindForType(Result); 8193 if (VK == VK_LValue) { 8194 LHS = ImplicitCastExpr::Create(Context, LHS.get()->getType(), 8195 CK_GetObjCProperty, LHS.take(), 0, VK); 8196 return; 8197 } 8198 } 8199 } 8200 8201 if (getLangOptions().CPlusPlus && LHSTy->isRecordType()) { 8202 InitializedEntity Entity = 8203 InitializedEntity::InitializeParameter(Context, LHSTy); 8204 ExprResult ArgE = PerformCopyInitialization(Entity, SourceLocation(), RHS); 8205 if (!ArgE.isInvalid()) 8206 RHS = ArgE; 8207 } 8208} 8209 8210 8211/// getPrimaryDecl - Helper function for CheckAddressOfOperand(). 8212/// This routine allows us to typecheck complex/recursive expressions 8213/// where the declaration is needed for type checking. We only need to 8214/// handle cases when the expression references a function designator 8215/// or is an lvalue. Here are some examples: 8216/// - &(x) => x 8217/// - &*****f => f for f a function designator. 8218/// - &s.xx => s 8219/// - &s.zz[1].yy -> s, if zz is an array 8220/// - *(x + 1) -> x, if x is an array 8221/// - &"123"[2] -> 0 8222/// - & __real__ x -> x 8223static ValueDecl *getPrimaryDecl(Expr *E) { 8224 switch (E->getStmtClass()) { 8225 case Stmt::DeclRefExprClass: 8226 return cast<DeclRefExpr>(E)->getDecl(); 8227 case Stmt::MemberExprClass: 8228 // If this is an arrow operator, the address is an offset from 8229 // the base's value, so the object the base refers to is 8230 // irrelevant. 8231 if (cast<MemberExpr>(E)->isArrow()) 8232 return 0; 8233 // Otherwise, the expression refers to a part of the base 8234 return getPrimaryDecl(cast<MemberExpr>(E)->getBase()); 8235 case Stmt::ArraySubscriptExprClass: { 8236 // FIXME: This code shouldn't be necessary! We should catch the implicit 8237 // promotion of register arrays earlier. 8238 Expr* Base = cast<ArraySubscriptExpr>(E)->getBase(); 8239 if (ImplicitCastExpr* ICE = dyn_cast<ImplicitCastExpr>(Base)) { 8240 if (ICE->getSubExpr()->getType()->isArrayType()) 8241 return getPrimaryDecl(ICE->getSubExpr()); 8242 } 8243 return 0; 8244 } 8245 case Stmt::UnaryOperatorClass: { 8246 UnaryOperator *UO = cast<UnaryOperator>(E); 8247 8248 switch(UO->getOpcode()) { 8249 case UO_Real: 8250 case UO_Imag: 8251 case UO_Extension: 8252 return getPrimaryDecl(UO->getSubExpr()); 8253 default: 8254 return 0; 8255 } 8256 } 8257 case Stmt::ParenExprClass: 8258 return getPrimaryDecl(cast<ParenExpr>(E)->getSubExpr()); 8259 case Stmt::ImplicitCastExprClass: 8260 // If the result of an implicit cast is an l-value, we care about 8261 // the sub-expression; otherwise, the result here doesn't matter. 8262 return getPrimaryDecl(cast<ImplicitCastExpr>(E)->getSubExpr()); 8263 default: 8264 return 0; 8265 } 8266} 8267 8268/// CheckAddressOfOperand - The operand of & must be either a function 8269/// designator or an lvalue designating an object. If it is an lvalue, the 8270/// object cannot be declared with storage class register or be a bit field. 8271/// Note: The usual conversions are *not* applied to the operand of the & 8272/// operator (C99 6.3.2.1p[2-4]), and its result is never an lvalue. 8273/// In C++, the operand might be an overloaded function name, in which case 8274/// we allow the '&' but retain the overloaded-function type. 8275static QualType CheckAddressOfOperand(Sema &S, Expr *OrigOp, 8276 SourceLocation OpLoc) { 8277 if (OrigOp->isTypeDependent()) 8278 return S.Context.DependentTy; 8279 if (OrigOp->getType() == S.Context.OverloadTy) 8280 return S.Context.OverloadTy; 8281 if (OrigOp->getType() == S.Context.UnknownAnyTy) 8282 return S.Context.UnknownAnyTy; 8283 8284 assert(!OrigOp->getType()->isPlaceholderType()); 8285 8286 // Make sure to ignore parentheses in subsequent checks 8287 Expr *op = OrigOp->IgnoreParens(); 8288 8289 if (S.getLangOptions().C99) { 8290 // Implement C99-only parts of addressof rules. 8291 if (UnaryOperator* uOp = dyn_cast<UnaryOperator>(op)) { 8292 if (uOp->getOpcode() == UO_Deref) 8293 // Per C99 6.5.3.2, the address of a deref always returns a valid result 8294 // (assuming the deref expression is valid). 8295 return uOp->getSubExpr()->getType(); 8296 } 8297 // Technically, there should be a check for array subscript 8298 // expressions here, but the result of one is always an lvalue anyway. 8299 } 8300 ValueDecl *dcl = getPrimaryDecl(op); 8301 Expr::LValueClassification lval = op->ClassifyLValue(S.Context); 8302 8303 if (lval == Expr::LV_ClassTemporary) { 8304 bool sfinae = S.isSFINAEContext(); 8305 S.Diag(OpLoc, sfinae ? diag::err_typecheck_addrof_class_temporary 8306 : diag::ext_typecheck_addrof_class_temporary) 8307 << op->getType() << op->getSourceRange(); 8308 if (sfinae) 8309 return QualType(); 8310 } else if (isa<ObjCSelectorExpr>(op)) { 8311 return S.Context.getPointerType(op->getType()); 8312 } else if (lval == Expr::LV_MemberFunction) { 8313 // If it's an instance method, make a member pointer. 8314 // The expression must have exactly the form &A::foo. 8315 8316 // If the underlying expression isn't a decl ref, give up. 8317 if (!isa<DeclRefExpr>(op)) { 8318 S.Diag(OpLoc, diag::err_invalid_form_pointer_member_function) 8319 << OrigOp->getSourceRange(); 8320 return QualType(); 8321 } 8322 DeclRefExpr *DRE = cast<DeclRefExpr>(op); 8323 CXXMethodDecl *MD = cast<CXXMethodDecl>(DRE->getDecl()); 8324 8325 // The id-expression was parenthesized. 8326 if (OrigOp != DRE) { 8327 S.Diag(OpLoc, diag::err_parens_pointer_member_function) 8328 << OrigOp->getSourceRange(); 8329 8330 // The method was named without a qualifier. 8331 } else if (!DRE->getQualifier()) { 8332 S.Diag(OpLoc, diag::err_unqualified_pointer_member_function) 8333 << op->getSourceRange(); 8334 } 8335 8336 return S.Context.getMemberPointerType(op->getType(), 8337 S.Context.getTypeDeclType(MD->getParent()).getTypePtr()); 8338 } else if (lval != Expr::LV_Valid && lval != Expr::LV_IncompleteVoidType) { 8339 // C99 6.5.3.2p1 8340 // The operand must be either an l-value or a function designator 8341 if (!op->getType()->isFunctionType()) { 8342 // FIXME: emit more specific diag... 8343 S.Diag(OpLoc, diag::err_typecheck_invalid_lvalue_addrof) 8344 << op->getSourceRange(); 8345 return QualType(); 8346 } 8347 } else if (op->getObjectKind() == OK_BitField) { // C99 6.5.3.2p1 8348 // The operand cannot be a bit-field 8349 S.Diag(OpLoc, diag::err_typecheck_address_of) 8350 << "bit-field" << op->getSourceRange(); 8351 return QualType(); 8352 } else if (op->getObjectKind() == OK_VectorComponent) { 8353 // The operand cannot be an element of a vector 8354 S.Diag(OpLoc, diag::err_typecheck_address_of) 8355 << "vector element" << op->getSourceRange(); 8356 return QualType(); 8357 } else if (op->getObjectKind() == OK_ObjCProperty) { 8358 // cannot take address of a property expression. 8359 S.Diag(OpLoc, diag::err_typecheck_address_of) 8360 << "property expression" << op->getSourceRange(); 8361 return QualType(); 8362 } else if (dcl) { // C99 6.5.3.2p1 8363 // We have an lvalue with a decl. Make sure the decl is not declared 8364 // with the register storage-class specifier. 8365 if (const VarDecl *vd = dyn_cast<VarDecl>(dcl)) { 8366 // in C++ it is not error to take address of a register 8367 // variable (c++03 7.1.1P3) 8368 if (vd->getStorageClass() == SC_Register && 8369 !S.getLangOptions().CPlusPlus) { 8370 S.Diag(OpLoc, diag::err_typecheck_address_of) 8371 << "register variable" << op->getSourceRange(); 8372 return QualType(); 8373 } 8374 } else if (isa<FunctionTemplateDecl>(dcl)) { 8375 return S.Context.OverloadTy; 8376 } else if (isa<FieldDecl>(dcl) || isa<IndirectFieldDecl>(dcl)) { 8377 // Okay: we can take the address of a field. 8378 // Could be a pointer to member, though, if there is an explicit 8379 // scope qualifier for the class. 8380 if (isa<DeclRefExpr>(op) && cast<DeclRefExpr>(op)->getQualifier()) { 8381 DeclContext *Ctx = dcl->getDeclContext(); 8382 if (Ctx && Ctx->isRecord()) { 8383 if (dcl->getType()->isReferenceType()) { 8384 S.Diag(OpLoc, 8385 diag::err_cannot_form_pointer_to_member_of_reference_type) 8386 << dcl->getDeclName() << dcl->getType(); 8387 return QualType(); 8388 } 8389 8390 while (cast<RecordDecl>(Ctx)->isAnonymousStructOrUnion()) 8391 Ctx = Ctx->getParent(); 8392 return S.Context.getMemberPointerType(op->getType(), 8393 S.Context.getTypeDeclType(cast<RecordDecl>(Ctx)).getTypePtr()); 8394 } 8395 } 8396 } else if (!isa<FunctionDecl>(dcl)) 8397 assert(0 && "Unknown/unexpected decl type"); 8398 } 8399 8400 if (lval == Expr::LV_IncompleteVoidType) { 8401 // Taking the address of a void variable is technically illegal, but we 8402 // allow it in cases which are otherwise valid. 8403 // Example: "extern void x; void* y = &x;". 8404 S.Diag(OpLoc, diag::ext_typecheck_addrof_void) << op->getSourceRange(); 8405 } 8406 8407 // If the operand has type "type", the result has type "pointer to type". 8408 if (op->getType()->isObjCObjectType()) 8409 return S.Context.getObjCObjectPointerType(op->getType()); 8410 return S.Context.getPointerType(op->getType()); 8411} 8412 8413/// CheckIndirectionOperand - Type check unary indirection (prefix '*'). 8414static QualType CheckIndirectionOperand(Sema &S, Expr *Op, ExprValueKind &VK, 8415 SourceLocation OpLoc) { 8416 if (Op->isTypeDependent()) 8417 return S.Context.DependentTy; 8418 8419 ExprResult ConvResult = S.UsualUnaryConversions(Op); 8420 if (ConvResult.isInvalid()) 8421 return QualType(); 8422 Op = ConvResult.take(); 8423 QualType OpTy = Op->getType(); 8424 QualType Result; 8425 8426 // Note that per both C89 and C99, indirection is always legal, even if OpTy 8427 // is an incomplete type or void. It would be possible to warn about 8428 // dereferencing a void pointer, but it's completely well-defined, and such a 8429 // warning is unlikely to catch any mistakes. 8430 if (const PointerType *PT = OpTy->getAs<PointerType>()) 8431 Result = PT->getPointeeType(); 8432 else if (const ObjCObjectPointerType *OPT = 8433 OpTy->getAs<ObjCObjectPointerType>()) 8434 Result = OPT->getPointeeType(); 8435 else { 8436 ExprResult PR = S.CheckPlaceholderExpr(Op); 8437 if (PR.isInvalid()) return QualType(); 8438 if (PR.take() != Op) 8439 return CheckIndirectionOperand(S, PR.take(), VK, OpLoc); 8440 } 8441 8442 if (Result.isNull()) { 8443 S.Diag(OpLoc, diag::err_typecheck_indirection_requires_pointer) 8444 << OpTy << Op->getSourceRange(); 8445 return QualType(); 8446 } 8447 8448 // Dereferences are usually l-values... 8449 VK = VK_LValue; 8450 8451 // ...except that certain expressions are never l-values in C. 8452 if (!S.getLangOptions().CPlusPlus && 8453 IsCForbiddenLValueType(S.Context, Result)) 8454 VK = VK_RValue; 8455 8456 return Result; 8457} 8458 8459static inline BinaryOperatorKind ConvertTokenKindToBinaryOpcode( 8460 tok::TokenKind Kind) { 8461 BinaryOperatorKind Opc; 8462 switch (Kind) { 8463 default: assert(0 && "Unknown binop!"); 8464 case tok::periodstar: Opc = BO_PtrMemD; break; 8465 case tok::arrowstar: Opc = BO_PtrMemI; break; 8466 case tok::star: Opc = BO_Mul; break; 8467 case tok::slash: Opc = BO_Div; break; 8468 case tok::percent: Opc = BO_Rem; break; 8469 case tok::plus: Opc = BO_Add; break; 8470 case tok::minus: Opc = BO_Sub; break; 8471 case tok::lessless: Opc = BO_Shl; break; 8472 case tok::greatergreater: Opc = BO_Shr; break; 8473 case tok::lessequal: Opc = BO_LE; break; 8474 case tok::less: Opc = BO_LT; break; 8475 case tok::greaterequal: Opc = BO_GE; break; 8476 case tok::greater: Opc = BO_GT; break; 8477 case tok::exclaimequal: Opc = BO_NE; break; 8478 case tok::equalequal: Opc = BO_EQ; break; 8479 case tok::amp: Opc = BO_And; break; 8480 case tok::caret: Opc = BO_Xor; break; 8481 case tok::pipe: Opc = BO_Or; break; 8482 case tok::ampamp: Opc = BO_LAnd; break; 8483 case tok::pipepipe: Opc = BO_LOr; break; 8484 case tok::equal: Opc = BO_Assign; break; 8485 case tok::starequal: Opc = BO_MulAssign; break; 8486 case tok::slashequal: Opc = BO_DivAssign; break; 8487 case tok::percentequal: Opc = BO_RemAssign; break; 8488 case tok::plusequal: Opc = BO_AddAssign; break; 8489 case tok::minusequal: Opc = BO_SubAssign; break; 8490 case tok::lesslessequal: Opc = BO_ShlAssign; break; 8491 case tok::greatergreaterequal: Opc = BO_ShrAssign; break; 8492 case tok::ampequal: Opc = BO_AndAssign; break; 8493 case tok::caretequal: Opc = BO_XorAssign; break; 8494 case tok::pipeequal: Opc = BO_OrAssign; break; 8495 case tok::comma: Opc = BO_Comma; break; 8496 } 8497 return Opc; 8498} 8499 8500static inline UnaryOperatorKind ConvertTokenKindToUnaryOpcode( 8501 tok::TokenKind Kind) { 8502 UnaryOperatorKind Opc; 8503 switch (Kind) { 8504 default: assert(0 && "Unknown unary op!"); 8505 case tok::plusplus: Opc = UO_PreInc; break; 8506 case tok::minusminus: Opc = UO_PreDec; break; 8507 case tok::amp: Opc = UO_AddrOf; break; 8508 case tok::star: Opc = UO_Deref; break; 8509 case tok::plus: Opc = UO_Plus; break; 8510 case tok::minus: Opc = UO_Minus; break; 8511 case tok::tilde: Opc = UO_Not; break; 8512 case tok::exclaim: Opc = UO_LNot; break; 8513 case tok::kw___real: Opc = UO_Real; break; 8514 case tok::kw___imag: Opc = UO_Imag; break; 8515 case tok::kw___extension__: Opc = UO_Extension; break; 8516 } 8517 return Opc; 8518} 8519 8520/// DiagnoseSelfAssignment - Emits a warning if a value is assigned to itself. 8521/// This warning is only emitted for builtin assignment operations. It is also 8522/// suppressed in the event of macro expansions. 8523static void DiagnoseSelfAssignment(Sema &S, Expr *lhs, Expr *rhs, 8524 SourceLocation OpLoc) { 8525 if (!S.ActiveTemplateInstantiations.empty()) 8526 return; 8527 if (OpLoc.isInvalid() || OpLoc.isMacroID()) 8528 return; 8529 lhs = lhs->IgnoreParenImpCasts(); 8530 rhs = rhs->IgnoreParenImpCasts(); 8531 const DeclRefExpr *LeftDeclRef = dyn_cast<DeclRefExpr>(lhs); 8532 const DeclRefExpr *RightDeclRef = dyn_cast<DeclRefExpr>(rhs); 8533 if (!LeftDeclRef || !RightDeclRef || 8534 LeftDeclRef->getLocation().isMacroID() || 8535 RightDeclRef->getLocation().isMacroID()) 8536 return; 8537 const ValueDecl *LeftDecl = 8538 cast<ValueDecl>(LeftDeclRef->getDecl()->getCanonicalDecl()); 8539 const ValueDecl *RightDecl = 8540 cast<ValueDecl>(RightDeclRef->getDecl()->getCanonicalDecl()); 8541 if (LeftDecl != RightDecl) 8542 return; 8543 if (LeftDecl->getType().isVolatileQualified()) 8544 return; 8545 if (const ReferenceType *RefTy = LeftDecl->getType()->getAs<ReferenceType>()) 8546 if (RefTy->getPointeeType().isVolatileQualified()) 8547 return; 8548 8549 S.Diag(OpLoc, diag::warn_self_assignment) 8550 << LeftDeclRef->getType() 8551 << lhs->getSourceRange() << rhs->getSourceRange(); 8552} 8553 8554/// CreateBuiltinBinOp - Creates a new built-in binary operation with 8555/// operator @p Opc at location @c TokLoc. This routine only supports 8556/// built-in operations; ActOnBinOp handles overloaded operators. 8557ExprResult Sema::CreateBuiltinBinOp(SourceLocation OpLoc, 8558 BinaryOperatorKind Opc, 8559 Expr *lhsExpr, Expr *rhsExpr) { 8560 ExprResult lhs = Owned(lhsExpr), rhs = Owned(rhsExpr); 8561 QualType ResultTy; // Result type of the binary operator. 8562 // The following two variables are used for compound assignment operators 8563 QualType CompLHSTy; // Type of LHS after promotions for computation 8564 QualType CompResultTy; // Type of computation result 8565 ExprValueKind VK = VK_RValue; 8566 ExprObjectKind OK = OK_Ordinary; 8567 8568 // Check if a 'foo<int>' involved in a binary op, identifies a single 8569 // function unambiguously (i.e. an lvalue ala 13.4) 8570 // But since an assignment can trigger target based overload, exclude it in 8571 // our blind search. i.e: 8572 // template<class T> void f(); template<class T, class U> void f(U); 8573 // f<int> == 0; // resolve f<int> blindly 8574 // void (*p)(int); p = f<int>; // resolve f<int> using target 8575 if (Opc != BO_Assign) { 8576 ExprResult resolvedLHS = CheckPlaceholderExpr(lhs.get()); 8577 if (!resolvedLHS.isUsable()) return ExprError(); 8578 lhs = move(resolvedLHS); 8579 8580 ExprResult resolvedRHS = CheckPlaceholderExpr(rhs.get()); 8581 if (!resolvedRHS.isUsable()) return ExprError(); 8582 rhs = move(resolvedRHS); 8583 } 8584 8585 switch (Opc) { 8586 case BO_Assign: 8587 ResultTy = CheckAssignmentOperands(lhs.get(), rhs, OpLoc, QualType()); 8588 if (getLangOptions().CPlusPlus && 8589 lhs.get()->getObjectKind() != OK_ObjCProperty) { 8590 VK = lhs.get()->getValueKind(); 8591 OK = lhs.get()->getObjectKind(); 8592 } 8593 if (!ResultTy.isNull()) 8594 DiagnoseSelfAssignment(*this, lhs.get(), rhs.get(), OpLoc); 8595 break; 8596 case BO_PtrMemD: 8597 case BO_PtrMemI: 8598 ResultTy = CheckPointerToMemberOperands(lhs, rhs, VK, OpLoc, 8599 Opc == BO_PtrMemI); 8600 break; 8601 case BO_Mul: 8602 case BO_Div: 8603 ResultTy = CheckMultiplyDivideOperands(lhs, rhs, OpLoc, false, 8604 Opc == BO_Div); 8605 break; 8606 case BO_Rem: 8607 ResultTy = CheckRemainderOperands(lhs, rhs, OpLoc); 8608 break; 8609 case BO_Add: 8610 ResultTy = CheckAdditionOperands(lhs, rhs, OpLoc); 8611 break; 8612 case BO_Sub: 8613 ResultTy = CheckSubtractionOperands(lhs, rhs, OpLoc); 8614 break; 8615 case BO_Shl: 8616 case BO_Shr: 8617 ResultTy = CheckShiftOperands(lhs, rhs, OpLoc, Opc); 8618 break; 8619 case BO_LE: 8620 case BO_LT: 8621 case BO_GE: 8622 case BO_GT: 8623 ResultTy = CheckCompareOperands(lhs, rhs, OpLoc, Opc, true); 8624 break; 8625 case BO_EQ: 8626 case BO_NE: 8627 ResultTy = CheckCompareOperands(lhs, rhs, OpLoc, Opc, false); 8628 break; 8629 case BO_And: 8630 case BO_Xor: 8631 case BO_Or: 8632 ResultTy = CheckBitwiseOperands(lhs, rhs, OpLoc); 8633 break; 8634 case BO_LAnd: 8635 case BO_LOr: 8636 ResultTy = CheckLogicalOperands(lhs, rhs, OpLoc, Opc); 8637 break; 8638 case BO_MulAssign: 8639 case BO_DivAssign: 8640 CompResultTy = CheckMultiplyDivideOperands(lhs, rhs, OpLoc, true, 8641 Opc == BO_DivAssign); 8642 CompLHSTy = CompResultTy; 8643 if (!CompResultTy.isNull() && !lhs.isInvalid() && !rhs.isInvalid()) 8644 ResultTy = CheckAssignmentOperands(lhs.get(), rhs, OpLoc, CompResultTy); 8645 break; 8646 case BO_RemAssign: 8647 CompResultTy = CheckRemainderOperands(lhs, rhs, OpLoc, true); 8648 CompLHSTy = CompResultTy; 8649 if (!CompResultTy.isNull() && !lhs.isInvalid() && !rhs.isInvalid()) 8650 ResultTy = CheckAssignmentOperands(lhs.get(), rhs, OpLoc, CompResultTy); 8651 break; 8652 case BO_AddAssign: 8653 CompResultTy = CheckAdditionOperands(lhs, rhs, OpLoc, &CompLHSTy); 8654 if (!CompResultTy.isNull() && !lhs.isInvalid() && !rhs.isInvalid()) 8655 ResultTy = CheckAssignmentOperands(lhs.get(), rhs, OpLoc, CompResultTy); 8656 break; 8657 case BO_SubAssign: 8658 CompResultTy = CheckSubtractionOperands(lhs, rhs, OpLoc, &CompLHSTy); 8659 if (!CompResultTy.isNull() && !lhs.isInvalid() && !rhs.isInvalid()) 8660 ResultTy = CheckAssignmentOperands(lhs.get(), rhs, OpLoc, CompResultTy); 8661 break; 8662 case BO_ShlAssign: 8663 case BO_ShrAssign: 8664 CompResultTy = CheckShiftOperands(lhs, rhs, OpLoc, Opc, true); 8665 CompLHSTy = CompResultTy; 8666 if (!CompResultTy.isNull() && !lhs.isInvalid() && !rhs.isInvalid()) 8667 ResultTy = CheckAssignmentOperands(lhs.get(), rhs, OpLoc, CompResultTy); 8668 break; 8669 case BO_AndAssign: 8670 case BO_XorAssign: 8671 case BO_OrAssign: 8672 CompResultTy = CheckBitwiseOperands(lhs, rhs, OpLoc, true); 8673 CompLHSTy = CompResultTy; 8674 if (!CompResultTy.isNull() && !lhs.isInvalid() && !rhs.isInvalid()) 8675 ResultTy = CheckAssignmentOperands(lhs.get(), rhs, OpLoc, CompResultTy); 8676 break; 8677 case BO_Comma: 8678 ResultTy = CheckCommaOperands(*this, lhs, rhs, OpLoc); 8679 if (getLangOptions().CPlusPlus && !rhs.isInvalid()) { 8680 VK = rhs.get()->getValueKind(); 8681 OK = rhs.get()->getObjectKind(); 8682 } 8683 break; 8684 } 8685 if (ResultTy.isNull() || lhs.isInvalid() || rhs.isInvalid()) 8686 return ExprError(); 8687 if (CompResultTy.isNull()) 8688 return Owned(new (Context) BinaryOperator(lhs.take(), rhs.take(), Opc, 8689 ResultTy, VK, OK, OpLoc)); 8690 if (getLangOptions().CPlusPlus && lhs.get()->getObjectKind() != OK_ObjCProperty) { 8691 VK = VK_LValue; 8692 OK = lhs.get()->getObjectKind(); 8693 } 8694 return Owned(new (Context) CompoundAssignOperator(lhs.take(), rhs.take(), Opc, 8695 ResultTy, VK, OK, CompLHSTy, 8696 CompResultTy, OpLoc)); 8697} 8698 8699/// SuggestParentheses - Emit a diagnostic together with a fixit hint that wraps 8700/// ParenRange in parentheses. 8701static void SuggestParentheses(Sema &Self, SourceLocation Loc, 8702 const PartialDiagnostic &PD, 8703 const PartialDiagnostic &FirstNote, 8704 SourceRange FirstParenRange, 8705 const PartialDiagnostic &SecondNote, 8706 SourceRange SecondParenRange) { 8707 Self.Diag(Loc, PD); 8708 8709 if (!FirstNote.getDiagID()) 8710 return; 8711 8712 SourceLocation EndLoc = Self.PP.getLocForEndOfToken(FirstParenRange.getEnd()); 8713 if (!FirstParenRange.getEnd().isFileID() || EndLoc.isInvalid()) { 8714 // We can't display the parentheses, so just return. 8715 return; 8716 } 8717 8718 Self.Diag(Loc, FirstNote) 8719 << FixItHint::CreateInsertion(FirstParenRange.getBegin(), "(") 8720 << FixItHint::CreateInsertion(EndLoc, ")"); 8721 8722 if (!SecondNote.getDiagID()) 8723 return; 8724 8725 EndLoc = Self.PP.getLocForEndOfToken(SecondParenRange.getEnd()); 8726 if (!SecondParenRange.getEnd().isFileID() || EndLoc.isInvalid()) { 8727 // We can't display the parentheses, so just dig the 8728 // warning/error and return. 8729 Self.Diag(Loc, SecondNote); 8730 return; 8731 } 8732 8733 Self.Diag(Loc, SecondNote) 8734 << FixItHint::CreateInsertion(SecondParenRange.getBegin(), "(") 8735 << FixItHint::CreateInsertion(EndLoc, ")"); 8736} 8737 8738/// DiagnoseBitwisePrecedence - Emit a warning when bitwise and comparison 8739/// operators are mixed in a way that suggests that the programmer forgot that 8740/// comparison operators have higher precedence. The most typical example of 8741/// such code is "flags & 0x0020 != 0", which is equivalent to "flags & 1". 8742static void DiagnoseBitwisePrecedence(Sema &Self, BinaryOperatorKind Opc, 8743 SourceLocation OpLoc,Expr *lhs,Expr *rhs){ 8744 typedef BinaryOperator BinOp; 8745 BinOp::Opcode lhsopc = static_cast<BinOp::Opcode>(-1), 8746 rhsopc = static_cast<BinOp::Opcode>(-1); 8747 if (BinOp *BO = dyn_cast<BinOp>(lhs)) 8748 lhsopc = BO->getOpcode(); 8749 if (BinOp *BO = dyn_cast<BinOp>(rhs)) 8750 rhsopc = BO->getOpcode(); 8751 8752 // Subs are not binary operators. 8753 if (lhsopc == -1 && rhsopc == -1) 8754 return; 8755 8756 // Bitwise operations are sometimes used as eager logical ops. 8757 // Don't diagnose this. 8758 if ((BinOp::isComparisonOp(lhsopc) || BinOp::isBitwiseOp(lhsopc)) && 8759 (BinOp::isComparisonOp(rhsopc) || BinOp::isBitwiseOp(rhsopc))) 8760 return; 8761 8762 if (BinOp::isComparisonOp(lhsopc)) 8763 SuggestParentheses(Self, OpLoc, 8764 Self.PDiag(diag::warn_precedence_bitwise_rel) 8765 << SourceRange(lhs->getLocStart(), OpLoc) 8766 << BinOp::getOpcodeStr(Opc) << BinOp::getOpcodeStr(lhsopc), 8767 Self.PDiag(diag::note_precedence_bitwise_first) 8768 << BinOp::getOpcodeStr(Opc), 8769 SourceRange(cast<BinOp>(lhs)->getRHS()->getLocStart(), rhs->getLocEnd()), 8770 Self.PDiag(diag::note_precedence_bitwise_silence) 8771 << BinOp::getOpcodeStr(lhsopc), 8772 lhs->getSourceRange()); 8773 else if (BinOp::isComparisonOp(rhsopc)) 8774 SuggestParentheses(Self, OpLoc, 8775 Self.PDiag(diag::warn_precedence_bitwise_rel) 8776 << SourceRange(OpLoc, rhs->getLocEnd()) 8777 << BinOp::getOpcodeStr(Opc) << BinOp::getOpcodeStr(rhsopc), 8778 Self.PDiag(diag::note_precedence_bitwise_first) 8779 << BinOp::getOpcodeStr(Opc), 8780 SourceRange(lhs->getLocEnd(), cast<BinOp>(rhs)->getLHS()->getLocStart()), 8781 Self.PDiag(diag::note_precedence_bitwise_silence) 8782 << BinOp::getOpcodeStr(rhsopc), 8783 rhs->getSourceRange()); 8784} 8785 8786/// \brief It accepts a '&&' expr that is inside a '||' one. 8787/// Emit a diagnostic together with a fixit hint that wraps the '&&' expression 8788/// in parentheses. 8789static void 8790EmitDiagnosticForLogicalAndInLogicalOr(Sema &Self, SourceLocation OpLoc, 8791 BinaryOperator *Bop) { 8792 assert(Bop->getOpcode() == BO_LAnd); 8793 SuggestParentheses(Self, Bop->getOperatorLoc(), 8794 Self.PDiag(diag::warn_logical_and_in_logical_or) 8795 << Bop->getSourceRange() << OpLoc, 8796 Self.PDiag(diag::note_logical_and_in_logical_or_silence), 8797 Bop->getSourceRange(), 8798 Self.PDiag(0), SourceRange()); 8799} 8800 8801/// \brief Returns true if the given expression can be evaluated as a constant 8802/// 'true'. 8803static bool EvaluatesAsTrue(Sema &S, Expr *E) { 8804 bool Res; 8805 return E->EvaluateAsBooleanCondition(Res, S.getASTContext()) && Res; 8806} 8807 8808/// \brief Returns true if the given expression can be evaluated as a constant 8809/// 'false'. 8810static bool EvaluatesAsFalse(Sema &S, Expr *E) { 8811 bool Res; 8812 return E->EvaluateAsBooleanCondition(Res, S.getASTContext()) && !Res; 8813} 8814 8815/// \brief Look for '&&' in the left hand of a '||' expr. 8816static void DiagnoseLogicalAndInLogicalOrLHS(Sema &S, SourceLocation OpLoc, 8817 Expr *OrLHS, Expr *OrRHS) { 8818 if (BinaryOperator *Bop = dyn_cast<BinaryOperator>(OrLHS)) { 8819 if (Bop->getOpcode() == BO_LAnd) { 8820 // If it's "a && b || 0" don't warn since the precedence doesn't matter. 8821 if (EvaluatesAsFalse(S, OrRHS)) 8822 return; 8823 // If it's "1 && a || b" don't warn since the precedence doesn't matter. 8824 if (!EvaluatesAsTrue(S, Bop->getLHS())) 8825 return EmitDiagnosticForLogicalAndInLogicalOr(S, OpLoc, Bop); 8826 } else if (Bop->getOpcode() == BO_LOr) { 8827 if (BinaryOperator *RBop = dyn_cast<BinaryOperator>(Bop->getRHS())) { 8828 // If it's "a || b && 1 || c" we didn't warn earlier for 8829 // "a || b && 1", but warn now. 8830 if (RBop->getOpcode() == BO_LAnd && EvaluatesAsTrue(S, RBop->getRHS())) 8831 return EmitDiagnosticForLogicalAndInLogicalOr(S, OpLoc, RBop); 8832 } 8833 } 8834 } 8835} 8836 8837/// \brief Look for '&&' in the right hand of a '||' expr. 8838static void DiagnoseLogicalAndInLogicalOrRHS(Sema &S, SourceLocation OpLoc, 8839 Expr *OrLHS, Expr *OrRHS) { 8840 if (BinaryOperator *Bop = dyn_cast<BinaryOperator>(OrRHS)) { 8841 if (Bop->getOpcode() == BO_LAnd) { 8842 // If it's "0 || a && b" don't warn since the precedence doesn't matter. 8843 if (EvaluatesAsFalse(S, OrLHS)) 8844 return; 8845 // If it's "a || b && 1" don't warn since the precedence doesn't matter. 8846 if (!EvaluatesAsTrue(S, Bop->getRHS())) 8847 return EmitDiagnosticForLogicalAndInLogicalOr(S, OpLoc, Bop); 8848 } 8849 } 8850} 8851 8852/// DiagnoseBinOpPrecedence - Emit warnings for expressions with tricky 8853/// precedence. 8854static void DiagnoseBinOpPrecedence(Sema &Self, BinaryOperatorKind Opc, 8855 SourceLocation OpLoc, Expr *lhs, Expr *rhs){ 8856 // Diagnose "arg1 'bitwise' arg2 'eq' arg3". 8857 if (BinaryOperator::isBitwiseOp(Opc)) 8858 return DiagnoseBitwisePrecedence(Self, Opc, OpLoc, lhs, rhs); 8859 8860 // Warn about arg1 || arg2 && arg3, as GCC 4.3+ does. 8861 // We don't warn for 'assert(a || b && "bad")' since this is safe. 8862 if (Opc == BO_LOr && !OpLoc.isMacroID()/* Don't warn in macros. */) { 8863 DiagnoseLogicalAndInLogicalOrLHS(Self, OpLoc, lhs, rhs); 8864 DiagnoseLogicalAndInLogicalOrRHS(Self, OpLoc, lhs, rhs); 8865 } 8866} 8867 8868// Binary Operators. 'Tok' is the token for the operator. 8869ExprResult Sema::ActOnBinOp(Scope *S, SourceLocation TokLoc, 8870 tok::TokenKind Kind, 8871 Expr *lhs, Expr *rhs) { 8872 BinaryOperatorKind Opc = ConvertTokenKindToBinaryOpcode(Kind); 8873 assert((lhs != 0) && "ActOnBinOp(): missing left expression"); 8874 assert((rhs != 0) && "ActOnBinOp(): missing right expression"); 8875 8876 // Emit warnings for tricky precedence issues, e.g. "bitfield & 0x4 == 0" 8877 DiagnoseBinOpPrecedence(*this, Opc, TokLoc, lhs, rhs); 8878 8879 return BuildBinOp(S, TokLoc, Opc, lhs, rhs); 8880} 8881 8882ExprResult Sema::BuildBinOp(Scope *S, SourceLocation OpLoc, 8883 BinaryOperatorKind Opc, 8884 Expr *lhs, Expr *rhs) { 8885 if (getLangOptions().CPlusPlus) { 8886 bool UseBuiltinOperator; 8887 8888 if (lhs->isTypeDependent() || rhs->isTypeDependent()) { 8889 UseBuiltinOperator = false; 8890 } else if (Opc == BO_Assign && lhs->getObjectKind() == OK_ObjCProperty) { 8891 UseBuiltinOperator = true; 8892 } else { 8893 UseBuiltinOperator = !lhs->getType()->isOverloadableType() && 8894 !rhs->getType()->isOverloadableType(); 8895 } 8896 8897 if (!UseBuiltinOperator) { 8898 // Find all of the overloaded operators visible from this 8899 // point. We perform both an operator-name lookup from the local 8900 // scope and an argument-dependent lookup based on the types of 8901 // the arguments. 8902 UnresolvedSet<16> Functions; 8903 OverloadedOperatorKind OverOp 8904 = BinaryOperator::getOverloadedOperator(Opc); 8905 if (S && OverOp != OO_None) 8906 LookupOverloadedOperatorName(OverOp, S, lhs->getType(), rhs->getType(), 8907 Functions); 8908 8909 // Build the (potentially-overloaded, potentially-dependent) 8910 // binary operation. 8911 return CreateOverloadedBinOp(OpLoc, Opc, Functions, lhs, rhs); 8912 } 8913 } 8914 8915 // Build a built-in binary operation. 8916 return CreateBuiltinBinOp(OpLoc, Opc, lhs, rhs); 8917} 8918 8919ExprResult Sema::CreateBuiltinUnaryOp(SourceLocation OpLoc, 8920 UnaryOperatorKind Opc, 8921 Expr *InputExpr) { 8922 ExprResult Input = Owned(InputExpr); 8923 ExprValueKind VK = VK_RValue; 8924 ExprObjectKind OK = OK_Ordinary; 8925 QualType resultType; 8926 switch (Opc) { 8927 case UO_PreInc: 8928 case UO_PreDec: 8929 case UO_PostInc: 8930 case UO_PostDec: 8931 resultType = CheckIncrementDecrementOperand(*this, Input.get(), VK, OpLoc, 8932 Opc == UO_PreInc || 8933 Opc == UO_PostInc, 8934 Opc == UO_PreInc || 8935 Opc == UO_PreDec); 8936 break; 8937 case UO_AddrOf: 8938 resultType = CheckAddressOfOperand(*this, Input.get(), OpLoc); 8939 break; 8940 case UO_Deref: { 8941 ExprResult resolved = CheckPlaceholderExpr(Input.get()); 8942 if (!resolved.isUsable()) return ExprError(); 8943 Input = move(resolved); 8944 Input = DefaultFunctionArrayLvalueConversion(Input.take()); 8945 resultType = CheckIndirectionOperand(*this, Input.get(), VK, OpLoc); 8946 break; 8947 } 8948 case UO_Plus: 8949 case UO_Minus: 8950 Input = UsualUnaryConversions(Input.take()); 8951 if (Input.isInvalid()) return ExprError(); 8952 resultType = Input.get()->getType(); 8953 if (resultType->isDependentType()) 8954 break; 8955 if (resultType->isArithmeticType() || // C99 6.5.3.3p1 8956 resultType->isVectorType()) 8957 break; 8958 else if (getLangOptions().CPlusPlus && // C++ [expr.unary.op]p6-7 8959 resultType->isEnumeralType()) 8960 break; 8961 else if (getLangOptions().CPlusPlus && // C++ [expr.unary.op]p6 8962 Opc == UO_Plus && 8963 resultType->isPointerType()) 8964 break; 8965 else if (resultType->isPlaceholderType()) { 8966 Input = CheckPlaceholderExpr(Input.take()); 8967 if (Input.isInvalid()) return ExprError(); 8968 return CreateBuiltinUnaryOp(OpLoc, Opc, Input.take()); 8969 } 8970 8971 return ExprError(Diag(OpLoc, diag::err_typecheck_unary_expr) 8972 << resultType << Input.get()->getSourceRange()); 8973 8974 case UO_Not: // bitwise complement 8975 Input = UsualUnaryConversions(Input.take()); 8976 if (Input.isInvalid()) return ExprError(); 8977 resultType = Input.get()->getType(); 8978 if (resultType->isDependentType()) 8979 break; 8980 // C99 6.5.3.3p1. We allow complex int and float as a GCC extension. 8981 if (resultType->isComplexType() || resultType->isComplexIntegerType()) 8982 // C99 does not support '~' for complex conjugation. 8983 Diag(OpLoc, diag::ext_integer_complement_complex) 8984 << resultType << Input.get()->getSourceRange(); 8985 else if (resultType->hasIntegerRepresentation()) 8986 break; 8987 else if (resultType->isPlaceholderType()) { 8988 Input = CheckPlaceholderExpr(Input.take()); 8989 if (Input.isInvalid()) return ExprError(); 8990 return CreateBuiltinUnaryOp(OpLoc, Opc, Input.take()); 8991 } else { 8992 return ExprError(Diag(OpLoc, diag::err_typecheck_unary_expr) 8993 << resultType << Input.get()->getSourceRange()); 8994 } 8995 break; 8996 8997 case UO_LNot: // logical negation 8998 // Unlike +/-/~, integer promotions aren't done here (C99 6.5.3.3p5). 8999 Input = DefaultFunctionArrayLvalueConversion(Input.take()); 9000 if (Input.isInvalid()) return ExprError(); 9001 resultType = Input.get()->getType(); 9002 if (resultType->isDependentType()) 9003 break; 9004 if (resultType->isScalarType()) { 9005 // C99 6.5.3.3p1: ok, fallthrough; 9006 if (Context.getLangOptions().CPlusPlus) { 9007 // C++03 [expr.unary.op]p8, C++0x [expr.unary.op]p9: 9008 // operand contextually converted to bool. 9009 Input = ImpCastExprToType(Input.take(), Context.BoolTy, 9010 ScalarTypeToBooleanCastKind(resultType)); 9011 } 9012 } else if (resultType->isPlaceholderType()) { 9013 Input = CheckPlaceholderExpr(Input.take()); 9014 if (Input.isInvalid()) return ExprError(); 9015 return CreateBuiltinUnaryOp(OpLoc, Opc, Input.take()); 9016 } else { 9017 return ExprError(Diag(OpLoc, diag::err_typecheck_unary_expr) 9018 << resultType << Input.get()->getSourceRange()); 9019 } 9020 9021 // LNot always has type int. C99 6.5.3.3p5. 9022 // In C++, it's bool. C++ 5.3.1p8 9023 resultType = Context.getLogicalOperationType(); 9024 break; 9025 case UO_Real: 9026 case UO_Imag: 9027 resultType = CheckRealImagOperand(*this, Input, OpLoc, Opc == UO_Real); 9028 // _Real and _Imag map ordinary l-values into ordinary l-values. 9029 if (Input.isInvalid()) return ExprError(); 9030 if (Input.get()->getValueKind() != VK_RValue && 9031 Input.get()->getObjectKind() == OK_Ordinary) 9032 VK = Input.get()->getValueKind(); 9033 break; 9034 case UO_Extension: 9035 resultType = Input.get()->getType(); 9036 VK = Input.get()->getValueKind(); 9037 OK = Input.get()->getObjectKind(); 9038 break; 9039 } 9040 if (resultType.isNull() || Input.isInvalid()) 9041 return ExprError(); 9042 9043 return Owned(new (Context) UnaryOperator(Input.take(), Opc, resultType, 9044 VK, OK, OpLoc)); 9045} 9046 9047ExprResult Sema::BuildUnaryOp(Scope *S, SourceLocation OpLoc, 9048 UnaryOperatorKind Opc, 9049 Expr *Input) { 9050 if (getLangOptions().CPlusPlus && Input->getType()->isOverloadableType() && 9051 UnaryOperator::getOverloadedOperator(Opc) != OO_None) { 9052 // Find all of the overloaded operators visible from this 9053 // point. We perform both an operator-name lookup from the local 9054 // scope and an argument-dependent lookup based on the types of 9055 // the arguments. 9056 UnresolvedSet<16> Functions; 9057 OverloadedOperatorKind OverOp = UnaryOperator::getOverloadedOperator(Opc); 9058 if (S && OverOp != OO_None) 9059 LookupOverloadedOperatorName(OverOp, S, Input->getType(), QualType(), 9060 Functions); 9061 9062 return CreateOverloadedUnaryOp(OpLoc, Opc, Functions, Input); 9063 } 9064 9065 return CreateBuiltinUnaryOp(OpLoc, Opc, Input); 9066} 9067 9068// Unary Operators. 'Tok' is the token for the operator. 9069ExprResult Sema::ActOnUnaryOp(Scope *S, SourceLocation OpLoc, 9070 tok::TokenKind Op, Expr *Input) { 9071 return BuildUnaryOp(S, OpLoc, ConvertTokenKindToUnaryOpcode(Op), Input); 9072} 9073 9074/// ActOnAddrLabel - Parse the GNU address of label extension: "&&foo". 9075ExprResult Sema::ActOnAddrLabel(SourceLocation OpLoc, SourceLocation LabLoc, 9076 LabelDecl *TheDecl) { 9077 TheDecl->setUsed(); 9078 // Create the AST node. The address of a label always has type 'void*'. 9079 return Owned(new (Context) AddrLabelExpr(OpLoc, LabLoc, TheDecl, 9080 Context.getPointerType(Context.VoidTy))); 9081} 9082 9083ExprResult 9084Sema::ActOnStmtExpr(SourceLocation LPLoc, Stmt *SubStmt, 9085 SourceLocation RPLoc) { // "({..})" 9086 assert(SubStmt && isa<CompoundStmt>(SubStmt) && "Invalid action invocation!"); 9087 CompoundStmt *Compound = cast<CompoundStmt>(SubStmt); 9088 9089 bool isFileScope 9090 = (getCurFunctionOrMethodDecl() == 0) && (getCurBlock() == 0); 9091 if (isFileScope) 9092 return ExprError(Diag(LPLoc, diag::err_stmtexpr_file_scope)); 9093 9094 // FIXME: there are a variety of strange constraints to enforce here, for 9095 // example, it is not possible to goto into a stmt expression apparently. 9096 // More semantic analysis is needed. 9097 9098 // If there are sub stmts in the compound stmt, take the type of the last one 9099 // as the type of the stmtexpr. 9100 QualType Ty = Context.VoidTy; 9101 bool StmtExprMayBindToTemp = false; 9102 if (!Compound->body_empty()) { 9103 Stmt *LastStmt = Compound->body_back(); 9104 LabelStmt *LastLabelStmt = 0; 9105 // If LastStmt is a label, skip down through into the body. 9106 while (LabelStmt *Label = dyn_cast<LabelStmt>(LastStmt)) { 9107 LastLabelStmt = Label; 9108 LastStmt = Label->getSubStmt(); 9109 } 9110 if (Expr *LastE = dyn_cast<Expr>(LastStmt)) { 9111 // Do function/array conversion on the last expression, but not 9112 // lvalue-to-rvalue. However, initialize an unqualified type. 9113 ExprResult LastExpr = DefaultFunctionArrayConversion(LastE); 9114 if (LastExpr.isInvalid()) 9115 return ExprError(); 9116 Ty = LastExpr.get()->getType().getUnqualifiedType(); 9117 9118 if (!Ty->isDependentType() && !LastExpr.get()->isTypeDependent()) { 9119 LastExpr = PerformCopyInitialization( 9120 InitializedEntity::InitializeResult(LPLoc, 9121 Ty, 9122 false), 9123 SourceLocation(), 9124 LastExpr); 9125 if (LastExpr.isInvalid()) 9126 return ExprError(); 9127 if (LastExpr.get() != 0) { 9128 if (!LastLabelStmt) 9129 Compound->setLastStmt(LastExpr.take()); 9130 else 9131 LastLabelStmt->setSubStmt(LastExpr.take()); 9132 StmtExprMayBindToTemp = true; 9133 } 9134 } 9135 } 9136 } 9137 9138 // FIXME: Check that expression type is complete/non-abstract; statement 9139 // expressions are not lvalues. 9140 Expr *ResStmtExpr = new (Context) StmtExpr(Compound, Ty, LPLoc, RPLoc); 9141 if (StmtExprMayBindToTemp) 9142 return MaybeBindToTemporary(ResStmtExpr); 9143 return Owned(ResStmtExpr); 9144} 9145 9146ExprResult Sema::BuildBuiltinOffsetOf(SourceLocation BuiltinLoc, 9147 TypeSourceInfo *TInfo, 9148 OffsetOfComponent *CompPtr, 9149 unsigned NumComponents, 9150 SourceLocation RParenLoc) { 9151 QualType ArgTy = TInfo->getType(); 9152 bool Dependent = ArgTy->isDependentType(); 9153 SourceRange TypeRange = TInfo->getTypeLoc().getLocalSourceRange(); 9154 9155 // We must have at least one component that refers to the type, and the first 9156 // one is known to be a field designator. Verify that the ArgTy represents 9157 // a struct/union/class. 9158 if (!Dependent && !ArgTy->isRecordType()) 9159 return ExprError(Diag(BuiltinLoc, diag::err_offsetof_record_type) 9160 << ArgTy << TypeRange); 9161 9162 // Type must be complete per C99 7.17p3 because a declaring a variable 9163 // with an incomplete type would be ill-formed. 9164 if (!Dependent 9165 && RequireCompleteType(BuiltinLoc, ArgTy, 9166 PDiag(diag::err_offsetof_incomplete_type) 9167 << TypeRange)) 9168 return ExprError(); 9169 9170 // offsetof with non-identifier designators (e.g. "offsetof(x, a.b[c])") are a 9171 // GCC extension, diagnose them. 9172 // FIXME: This diagnostic isn't actually visible because the location is in 9173 // a system header! 9174 if (NumComponents != 1) 9175 Diag(BuiltinLoc, diag::ext_offsetof_extended_field_designator) 9176 << SourceRange(CompPtr[1].LocStart, CompPtr[NumComponents-1].LocEnd); 9177 9178 bool DidWarnAboutNonPOD = false; 9179 QualType CurrentType = ArgTy; 9180 typedef OffsetOfExpr::OffsetOfNode OffsetOfNode; 9181 llvm::SmallVector<OffsetOfNode, 4> Comps; 9182 llvm::SmallVector<Expr*, 4> Exprs; 9183 for (unsigned i = 0; i != NumComponents; ++i) { 9184 const OffsetOfComponent &OC = CompPtr[i]; 9185 if (OC.isBrackets) { 9186 // Offset of an array sub-field. TODO: Should we allow vector elements? 9187 if (!CurrentType->isDependentType()) { 9188 const ArrayType *AT = Context.getAsArrayType(CurrentType); 9189 if(!AT) 9190 return ExprError(Diag(OC.LocEnd, diag::err_offsetof_array_type) 9191 << CurrentType); 9192 CurrentType = AT->getElementType(); 9193 } else 9194 CurrentType = Context.DependentTy; 9195 9196 // The expression must be an integral expression. 9197 // FIXME: An integral constant expression? 9198 Expr *Idx = static_cast<Expr*>(OC.U.E); 9199 if (!Idx->isTypeDependent() && !Idx->isValueDependent() && 9200 !Idx->getType()->isIntegerType()) 9201 return ExprError(Diag(Idx->getLocStart(), 9202 diag::err_typecheck_subscript_not_integer) 9203 << Idx->getSourceRange()); 9204 9205 // Record this array index. 9206 Comps.push_back(OffsetOfNode(OC.LocStart, Exprs.size(), OC.LocEnd)); 9207 Exprs.push_back(Idx); 9208 continue; 9209 } 9210 9211 // Offset of a field. 9212 if (CurrentType->isDependentType()) { 9213 // We have the offset of a field, but we can't look into the dependent 9214 // type. Just record the identifier of the field. 9215 Comps.push_back(OffsetOfNode(OC.LocStart, OC.U.IdentInfo, OC.LocEnd)); 9216 CurrentType = Context.DependentTy; 9217 continue; 9218 } 9219 9220 // We need to have a complete type to look into. 9221 if (RequireCompleteType(OC.LocStart, CurrentType, 9222 diag::err_offsetof_incomplete_type)) 9223 return ExprError(); 9224 9225 // Look for the designated field. 9226 const RecordType *RC = CurrentType->getAs<RecordType>(); 9227 if (!RC) 9228 return ExprError(Diag(OC.LocEnd, diag::err_offsetof_record_type) 9229 << CurrentType); 9230 RecordDecl *RD = RC->getDecl(); 9231 9232 // C++ [lib.support.types]p5: 9233 // The macro offsetof accepts a restricted set of type arguments in this 9234 // International Standard. type shall be a POD structure or a POD union 9235 // (clause 9). 9236 if (CXXRecordDecl *CRD = dyn_cast<CXXRecordDecl>(RD)) { 9237 if (!CRD->isPOD() && !DidWarnAboutNonPOD && 9238 DiagRuntimeBehavior(BuiltinLoc, 0, 9239 PDiag(diag::warn_offsetof_non_pod_type) 9240 << SourceRange(CompPtr[0].LocStart, OC.LocEnd) 9241 << CurrentType)) 9242 DidWarnAboutNonPOD = true; 9243 } 9244 9245 // Look for the field. 9246 LookupResult R(*this, OC.U.IdentInfo, OC.LocStart, LookupMemberName); 9247 LookupQualifiedName(R, RD); 9248 FieldDecl *MemberDecl = R.getAsSingle<FieldDecl>(); 9249 IndirectFieldDecl *IndirectMemberDecl = 0; 9250 if (!MemberDecl) { 9251 if ((IndirectMemberDecl = R.getAsSingle<IndirectFieldDecl>())) 9252 MemberDecl = IndirectMemberDecl->getAnonField(); 9253 } 9254 9255 if (!MemberDecl) 9256 return ExprError(Diag(BuiltinLoc, diag::err_no_member) 9257 << OC.U.IdentInfo << RD << SourceRange(OC.LocStart, 9258 OC.LocEnd)); 9259 9260 // C99 7.17p3: 9261 // (If the specified member is a bit-field, the behavior is undefined.) 9262 // 9263 // We diagnose this as an error. 9264 if (MemberDecl->getBitWidth()) { 9265 Diag(OC.LocEnd, diag::err_offsetof_bitfield) 9266 << MemberDecl->getDeclName() 9267 << SourceRange(BuiltinLoc, RParenLoc); 9268 Diag(MemberDecl->getLocation(), diag::note_bitfield_decl); 9269 return ExprError(); 9270 } 9271 9272 RecordDecl *Parent = MemberDecl->getParent(); 9273 if (IndirectMemberDecl) 9274 Parent = cast<RecordDecl>(IndirectMemberDecl->getDeclContext()); 9275 9276 // If the member was found in a base class, introduce OffsetOfNodes for 9277 // the base class indirections. 9278 CXXBasePaths Paths(/*FindAmbiguities=*/true, /*RecordPaths=*/true, 9279 /*DetectVirtual=*/false); 9280 if (IsDerivedFrom(CurrentType, Context.getTypeDeclType(Parent), Paths)) { 9281 CXXBasePath &Path = Paths.front(); 9282 for (CXXBasePath::iterator B = Path.begin(), BEnd = Path.end(); 9283 B != BEnd; ++B) 9284 Comps.push_back(OffsetOfNode(B->Base)); 9285 } 9286 9287 if (IndirectMemberDecl) { 9288 for (IndirectFieldDecl::chain_iterator FI = 9289 IndirectMemberDecl->chain_begin(), 9290 FEnd = IndirectMemberDecl->chain_end(); FI != FEnd; FI++) { 9291 assert(isa<FieldDecl>(*FI)); 9292 Comps.push_back(OffsetOfNode(OC.LocStart, 9293 cast<FieldDecl>(*FI), OC.LocEnd)); 9294 } 9295 } else 9296 Comps.push_back(OffsetOfNode(OC.LocStart, MemberDecl, OC.LocEnd)); 9297 9298 CurrentType = MemberDecl->getType().getNonReferenceType(); 9299 } 9300 9301 return Owned(OffsetOfExpr::Create(Context, Context.getSizeType(), BuiltinLoc, 9302 TInfo, Comps.data(), Comps.size(), 9303 Exprs.data(), Exprs.size(), RParenLoc)); 9304} 9305 9306ExprResult Sema::ActOnBuiltinOffsetOf(Scope *S, 9307 SourceLocation BuiltinLoc, 9308 SourceLocation TypeLoc, 9309 ParsedType argty, 9310 OffsetOfComponent *CompPtr, 9311 unsigned NumComponents, 9312 SourceLocation RPLoc) { 9313 9314 TypeSourceInfo *ArgTInfo; 9315 QualType ArgTy = GetTypeFromParser(argty, &ArgTInfo); 9316 if (ArgTy.isNull()) 9317 return ExprError(); 9318 9319 if (!ArgTInfo) 9320 ArgTInfo = Context.getTrivialTypeSourceInfo(ArgTy, TypeLoc); 9321 9322 return BuildBuiltinOffsetOf(BuiltinLoc, ArgTInfo, CompPtr, NumComponents, 9323 RPLoc); 9324} 9325 9326 9327ExprResult Sema::ActOnChooseExpr(SourceLocation BuiltinLoc, 9328 Expr *CondExpr, 9329 Expr *LHSExpr, Expr *RHSExpr, 9330 SourceLocation RPLoc) { 9331 assert((CondExpr && LHSExpr && RHSExpr) && "Missing type argument(s)"); 9332 9333 ExprValueKind VK = VK_RValue; 9334 ExprObjectKind OK = OK_Ordinary; 9335 QualType resType; 9336 bool ValueDependent = false; 9337 if (CondExpr->isTypeDependent() || CondExpr->isValueDependent()) { 9338 resType = Context.DependentTy; 9339 ValueDependent = true; 9340 } else { 9341 // The conditional expression is required to be a constant expression. 9342 llvm::APSInt condEval(32); 9343 SourceLocation ExpLoc; 9344 if (!CondExpr->isIntegerConstantExpr(condEval, Context, &ExpLoc)) 9345 return ExprError(Diag(ExpLoc, 9346 diag::err_typecheck_choose_expr_requires_constant) 9347 << CondExpr->getSourceRange()); 9348 9349 // If the condition is > zero, then the AST type is the same as the LSHExpr. 9350 Expr *ActiveExpr = condEval.getZExtValue() ? LHSExpr : RHSExpr; 9351 9352 resType = ActiveExpr->getType(); 9353 ValueDependent = ActiveExpr->isValueDependent(); 9354 VK = ActiveExpr->getValueKind(); 9355 OK = ActiveExpr->getObjectKind(); 9356 } 9357 9358 return Owned(new (Context) ChooseExpr(BuiltinLoc, CondExpr, LHSExpr, RHSExpr, 9359 resType, VK, OK, RPLoc, 9360 resType->isDependentType(), 9361 ValueDependent)); 9362} 9363 9364//===----------------------------------------------------------------------===// 9365// Clang Extensions. 9366//===----------------------------------------------------------------------===// 9367 9368/// ActOnBlockStart - This callback is invoked when a block literal is started. 9369void Sema::ActOnBlockStart(SourceLocation CaretLoc, Scope *BlockScope) { 9370 BlockDecl *Block = BlockDecl::Create(Context, CurContext, CaretLoc); 9371 PushBlockScope(BlockScope, Block); 9372 CurContext->addDecl(Block); 9373 if (BlockScope) 9374 PushDeclContext(BlockScope, Block); 9375 else 9376 CurContext = Block; 9377} 9378 9379void Sema::ActOnBlockArguments(Declarator &ParamInfo, Scope *CurScope) { 9380 assert(ParamInfo.getIdentifier()==0 && "block-id should have no identifier!"); 9381 assert(ParamInfo.getContext() == Declarator::BlockLiteralContext); 9382 BlockScopeInfo *CurBlock = getCurBlock(); 9383 9384 TypeSourceInfo *Sig = GetTypeForDeclarator(ParamInfo, CurScope); 9385 QualType T = Sig->getType(); 9386 9387 // GetTypeForDeclarator always produces a function type for a block 9388 // literal signature. Furthermore, it is always a FunctionProtoType 9389 // unless the function was written with a typedef. 9390 assert(T->isFunctionType() && 9391 "GetTypeForDeclarator made a non-function block signature"); 9392 9393 // Look for an explicit signature in that function type. 9394 FunctionProtoTypeLoc ExplicitSignature; 9395 9396 TypeLoc tmp = Sig->getTypeLoc().IgnoreParens(); 9397 if (isa<FunctionProtoTypeLoc>(tmp)) { 9398 ExplicitSignature = cast<FunctionProtoTypeLoc>(tmp); 9399 9400 // Check whether that explicit signature was synthesized by 9401 // GetTypeForDeclarator. If so, don't save that as part of the 9402 // written signature. 9403 if (ExplicitSignature.getLocalRangeBegin() == 9404 ExplicitSignature.getLocalRangeEnd()) { 9405 // This would be much cheaper if we stored TypeLocs instead of 9406 // TypeSourceInfos. 9407 TypeLoc Result = ExplicitSignature.getResultLoc(); 9408 unsigned Size = Result.getFullDataSize(); 9409 Sig = Context.CreateTypeSourceInfo(Result.getType(), Size); 9410 Sig->getTypeLoc().initializeFullCopy(Result, Size); 9411 9412 ExplicitSignature = FunctionProtoTypeLoc(); 9413 } 9414 } 9415 9416 CurBlock->TheDecl->setSignatureAsWritten(Sig); 9417 CurBlock->FunctionType = T; 9418 9419 const FunctionType *Fn = T->getAs<FunctionType>(); 9420 QualType RetTy = Fn->getResultType(); 9421 bool isVariadic = 9422 (isa<FunctionProtoType>(Fn) && cast<FunctionProtoType>(Fn)->isVariadic()); 9423 9424 CurBlock->TheDecl->setIsVariadic(isVariadic); 9425 9426 // Don't allow returning a objc interface by value. 9427 if (RetTy->isObjCObjectType()) { 9428 Diag(ParamInfo.getSourceRange().getBegin(), 9429 diag::err_object_cannot_be_passed_returned_by_value) << 0 << RetTy; 9430 return; 9431 } 9432 9433 // Context.DependentTy is used as a placeholder for a missing block 9434 // return type. TODO: what should we do with declarators like: 9435 // ^ * { ... } 9436 // If the answer is "apply template argument deduction".... 9437 if (RetTy != Context.DependentTy) 9438 CurBlock->ReturnType = RetTy; 9439 9440 // Push block parameters from the declarator if we had them. 9441 llvm::SmallVector<ParmVarDecl*, 8> Params; 9442 if (ExplicitSignature) { 9443 for (unsigned I = 0, E = ExplicitSignature.getNumArgs(); I != E; ++I) { 9444 ParmVarDecl *Param = ExplicitSignature.getArg(I); 9445 if (Param->getIdentifier() == 0 && 9446 !Param->isImplicit() && 9447 !Param->isInvalidDecl() && 9448 !getLangOptions().CPlusPlus) 9449 Diag(Param->getLocation(), diag::err_parameter_name_omitted); 9450 Params.push_back(Param); 9451 } 9452 9453 // Fake up parameter variables if we have a typedef, like 9454 // ^ fntype { ... } 9455 } else if (const FunctionProtoType *Fn = T->getAs<FunctionProtoType>()) { 9456 for (FunctionProtoType::arg_type_iterator 9457 I = Fn->arg_type_begin(), E = Fn->arg_type_end(); I != E; ++I) { 9458 ParmVarDecl *Param = 9459 BuildParmVarDeclForTypedef(CurBlock->TheDecl, 9460 ParamInfo.getSourceRange().getBegin(), 9461 *I); 9462 Params.push_back(Param); 9463 } 9464 } 9465 9466 // Set the parameters on the block decl. 9467 if (!Params.empty()) { 9468 CurBlock->TheDecl->setParams(Params.data(), Params.size()); 9469 CheckParmsForFunctionDef(CurBlock->TheDecl->param_begin(), 9470 CurBlock->TheDecl->param_end(), 9471 /*CheckParameterNames=*/false); 9472 } 9473 9474 // Finally we can process decl attributes. 9475 ProcessDeclAttributes(CurScope, CurBlock->TheDecl, ParamInfo); 9476 9477 if (!isVariadic && CurBlock->TheDecl->getAttr<SentinelAttr>()) { 9478 Diag(ParamInfo.getAttributes()->getLoc(), 9479 diag::warn_attribute_sentinel_not_variadic) << 1; 9480 // FIXME: remove the attribute. 9481 } 9482 9483 // Put the parameter variables in scope. We can bail out immediately 9484 // if we don't have any. 9485 if (Params.empty()) 9486 return; 9487 9488 for (BlockDecl::param_iterator AI = CurBlock->TheDecl->param_begin(), 9489 E = CurBlock->TheDecl->param_end(); AI != E; ++AI) { 9490 (*AI)->setOwningFunction(CurBlock->TheDecl); 9491 9492 // If this has an identifier, add it to the scope stack. 9493 if ((*AI)->getIdentifier()) { 9494 CheckShadow(CurBlock->TheScope, *AI); 9495 9496 PushOnScopeChains(*AI, CurBlock->TheScope); 9497 } 9498 } 9499} 9500 9501/// ActOnBlockError - If there is an error parsing a block, this callback 9502/// is invoked to pop the information about the block from the action impl. 9503void Sema::ActOnBlockError(SourceLocation CaretLoc, Scope *CurScope) { 9504 // Pop off CurBlock, handle nested blocks. 9505 PopDeclContext(); 9506 PopFunctionOrBlockScope(); 9507} 9508 9509/// ActOnBlockStmtExpr - This is called when the body of a block statement 9510/// literal was successfully completed. ^(int x){...} 9511ExprResult Sema::ActOnBlockStmtExpr(SourceLocation CaretLoc, 9512 Stmt *Body, Scope *CurScope) { 9513 // If blocks are disabled, emit an error. 9514 if (!LangOpts.Blocks) 9515 Diag(CaretLoc, diag::err_blocks_disable); 9516 9517 BlockScopeInfo *BSI = cast<BlockScopeInfo>(FunctionScopes.back()); 9518 9519 PopDeclContext(); 9520 9521 QualType RetTy = Context.VoidTy; 9522 if (!BSI->ReturnType.isNull()) 9523 RetTy = BSI->ReturnType; 9524 9525 bool NoReturn = BSI->TheDecl->getAttr<NoReturnAttr>(); 9526 QualType BlockTy; 9527 9528 // Set the captured variables on the block. 9529 BSI->TheDecl->setCaptures(Context, BSI->Captures.begin(), BSI->Captures.end(), 9530 BSI->CapturesCXXThis); 9531 9532 // If the user wrote a function type in some form, try to use that. 9533 if (!BSI->FunctionType.isNull()) { 9534 const FunctionType *FTy = BSI->FunctionType->getAs<FunctionType>(); 9535 9536 FunctionType::ExtInfo Ext = FTy->getExtInfo(); 9537 if (NoReturn && !Ext.getNoReturn()) Ext = Ext.withNoReturn(true); 9538 9539 // Turn protoless block types into nullary block types. 9540 if (isa<FunctionNoProtoType>(FTy)) { 9541 FunctionProtoType::ExtProtoInfo EPI; 9542 EPI.ExtInfo = Ext; 9543 BlockTy = Context.getFunctionType(RetTy, 0, 0, EPI); 9544 9545 // Otherwise, if we don't need to change anything about the function type, 9546 // preserve its sugar structure. 9547 } else if (FTy->getResultType() == RetTy && 9548 (!NoReturn || FTy->getNoReturnAttr())) { 9549 BlockTy = BSI->FunctionType; 9550 9551 // Otherwise, make the minimal modifications to the function type. 9552 } else { 9553 const FunctionProtoType *FPT = cast<FunctionProtoType>(FTy); 9554 FunctionProtoType::ExtProtoInfo EPI = FPT->getExtProtoInfo(); 9555 EPI.TypeQuals = 0; // FIXME: silently? 9556 EPI.ExtInfo = Ext; 9557 BlockTy = Context.getFunctionType(RetTy, 9558 FPT->arg_type_begin(), 9559 FPT->getNumArgs(), 9560 EPI); 9561 } 9562 9563 // If we don't have a function type, just build one from nothing. 9564 } else { 9565 FunctionProtoType::ExtProtoInfo EPI; 9566 EPI.ExtInfo = FunctionType::ExtInfo(NoReturn, false, 0, CC_Default); 9567 BlockTy = Context.getFunctionType(RetTy, 0, 0, EPI); 9568 } 9569 9570 DiagnoseUnusedParameters(BSI->TheDecl->param_begin(), 9571 BSI->TheDecl->param_end()); 9572 BlockTy = Context.getBlockPointerType(BlockTy); 9573 9574 // If needed, diagnose invalid gotos and switches in the block. 9575 if (getCurFunction()->NeedsScopeChecking() && !hasAnyErrorsInThisFunction()) 9576 DiagnoseInvalidJumps(cast<CompoundStmt>(Body)); 9577 9578 BSI->TheDecl->setBody(cast<CompoundStmt>(Body)); 9579 9580 BlockExpr *Result = new (Context) BlockExpr(BSI->TheDecl, BlockTy); 9581 9582 const AnalysisBasedWarnings::Policy &WP = AnalysisWarnings.getDefaultPolicy(); 9583 PopFunctionOrBlockScope(&WP, Result->getBlockDecl(), Result); 9584 return Owned(Result); 9585} 9586 9587ExprResult Sema::ActOnVAArg(SourceLocation BuiltinLoc, 9588 Expr *expr, ParsedType type, 9589 SourceLocation RPLoc) { 9590 TypeSourceInfo *TInfo; 9591 GetTypeFromParser(type, &TInfo); 9592 return BuildVAArgExpr(BuiltinLoc, expr, TInfo, RPLoc); 9593} 9594 9595ExprResult Sema::BuildVAArgExpr(SourceLocation BuiltinLoc, 9596 Expr *E, TypeSourceInfo *TInfo, 9597 SourceLocation RPLoc) { 9598 Expr *OrigExpr = E; 9599 9600 // Get the va_list type 9601 QualType VaListType = Context.getBuiltinVaListType(); 9602 if (VaListType->isArrayType()) { 9603 // Deal with implicit array decay; for example, on x86-64, 9604 // va_list is an array, but it's supposed to decay to 9605 // a pointer for va_arg. 9606 VaListType = Context.getArrayDecayedType(VaListType); 9607 // Make sure the input expression also decays appropriately. 9608 ExprResult Result = UsualUnaryConversions(E); 9609 if (Result.isInvalid()) 9610 return ExprError(); 9611 E = Result.take(); 9612 } else { 9613 // Otherwise, the va_list argument must be an l-value because 9614 // it is modified by va_arg. 9615 if (!E->isTypeDependent() && 9616 CheckForModifiableLvalue(E, BuiltinLoc, *this)) 9617 return ExprError(); 9618 } 9619 9620 if (!E->isTypeDependent() && 9621 !Context.hasSameType(VaListType, E->getType())) { 9622 return ExprError(Diag(E->getLocStart(), 9623 diag::err_first_argument_to_va_arg_not_of_type_va_list) 9624 << OrigExpr->getType() << E->getSourceRange()); 9625 } 9626 9627 // FIXME: Check that type is complete/non-abstract 9628 // FIXME: Warn if a non-POD type is passed in. 9629 9630 QualType T = TInfo->getType().getNonLValueExprType(Context); 9631 return Owned(new (Context) VAArgExpr(BuiltinLoc, E, TInfo, RPLoc, T)); 9632} 9633 9634ExprResult Sema::ActOnGNUNullExpr(SourceLocation TokenLoc) { 9635 // The type of __null will be int or long, depending on the size of 9636 // pointers on the target. 9637 QualType Ty; 9638 unsigned pw = Context.Target.getPointerWidth(0); 9639 if (pw == Context.Target.getIntWidth()) 9640 Ty = Context.IntTy; 9641 else if (pw == Context.Target.getLongWidth()) 9642 Ty = Context.LongTy; 9643 else if (pw == Context.Target.getLongLongWidth()) 9644 Ty = Context.LongLongTy; 9645 else { 9646 assert(!"I don't know size of pointer!"); 9647 Ty = Context.IntTy; 9648 } 9649 9650 return Owned(new (Context) GNUNullExpr(Ty, TokenLoc)); 9651} 9652 9653static void MakeObjCStringLiteralFixItHint(Sema& SemaRef, QualType DstType, 9654 Expr *SrcExpr, FixItHint &Hint) { 9655 if (!SemaRef.getLangOptions().ObjC1) 9656 return; 9657 9658 const ObjCObjectPointerType *PT = DstType->getAs<ObjCObjectPointerType>(); 9659 if (!PT) 9660 return; 9661 9662 // Check if the destination is of type 'id'. 9663 if (!PT->isObjCIdType()) { 9664 // Check if the destination is the 'NSString' interface. 9665 const ObjCInterfaceDecl *ID = PT->getInterfaceDecl(); 9666 if (!ID || !ID->getIdentifier()->isStr("NSString")) 9667 return; 9668 } 9669 9670 // Strip off any parens and casts. 9671 StringLiteral *SL = dyn_cast<StringLiteral>(SrcExpr->IgnoreParenCasts()); 9672 if (!SL || SL->isWide()) 9673 return; 9674 9675 Hint = FixItHint::CreateInsertion(SL->getLocStart(), "@"); 9676} 9677 9678bool Sema::DiagnoseAssignmentResult(AssignConvertType ConvTy, 9679 SourceLocation Loc, 9680 QualType DstType, QualType SrcType, 9681 Expr *SrcExpr, AssignmentAction Action, 9682 bool *Complained) { 9683 if (Complained) 9684 *Complained = false; 9685 9686 // Decode the result (notice that AST's are still created for extensions). 9687 bool isInvalid = false; 9688 unsigned DiagKind; 9689 FixItHint Hint; 9690 9691 switch (ConvTy) { 9692 default: assert(0 && "Unknown conversion type"); 9693 case Compatible: return false; 9694 case PointerToInt: 9695 DiagKind = diag::ext_typecheck_convert_pointer_int; 9696 break; 9697 case IntToPointer: 9698 DiagKind = diag::ext_typecheck_convert_int_pointer; 9699 break; 9700 case IncompatiblePointer: 9701 MakeObjCStringLiteralFixItHint(*this, DstType, SrcExpr, Hint); 9702 DiagKind = diag::ext_typecheck_convert_incompatible_pointer; 9703 break; 9704 case IncompatiblePointerSign: 9705 DiagKind = diag::ext_typecheck_convert_incompatible_pointer_sign; 9706 break; 9707 case FunctionVoidPointer: 9708 DiagKind = diag::ext_typecheck_convert_pointer_void_func; 9709 break; 9710 case IncompatiblePointerDiscardsQualifiers: { 9711 // Perform array-to-pointer decay if necessary. 9712 if (SrcType->isArrayType()) SrcType = Context.getArrayDecayedType(SrcType); 9713 9714 Qualifiers lhq = SrcType->getPointeeType().getQualifiers(); 9715 Qualifiers rhq = DstType->getPointeeType().getQualifiers(); 9716 if (lhq.getAddressSpace() != rhq.getAddressSpace()) { 9717 DiagKind = diag::err_typecheck_incompatible_address_space; 9718 break; 9719 } 9720 9721 llvm_unreachable("unknown error case for discarding qualifiers!"); 9722 // fallthrough 9723 } 9724 case CompatiblePointerDiscardsQualifiers: 9725 // If the qualifiers lost were because we were applying the 9726 // (deprecated) C++ conversion from a string literal to a char* 9727 // (or wchar_t*), then there was no error (C++ 4.2p2). FIXME: 9728 // Ideally, this check would be performed in 9729 // checkPointerTypesForAssignment. However, that would require a 9730 // bit of refactoring (so that the second argument is an 9731 // expression, rather than a type), which should be done as part 9732 // of a larger effort to fix checkPointerTypesForAssignment for 9733 // C++ semantics. 9734 if (getLangOptions().CPlusPlus && 9735 IsStringLiteralToNonConstPointerConversion(SrcExpr, DstType)) 9736 return false; 9737 DiagKind = diag::ext_typecheck_convert_discards_qualifiers; 9738 break; 9739 case IncompatibleNestedPointerQualifiers: 9740 DiagKind = diag::ext_nested_pointer_qualifier_mismatch; 9741 break; 9742 case IntToBlockPointer: 9743 DiagKind = diag::err_int_to_block_pointer; 9744 break; 9745 case IncompatibleBlockPointer: 9746 DiagKind = diag::err_typecheck_convert_incompatible_block_pointer; 9747 break; 9748 case IncompatibleObjCQualifiedId: 9749 // FIXME: Diagnose the problem in ObjCQualifiedIdTypesAreCompatible, since 9750 // it can give a more specific diagnostic. 9751 DiagKind = diag::warn_incompatible_qualified_id; 9752 break; 9753 case IncompatibleVectors: 9754 DiagKind = diag::warn_incompatible_vectors; 9755 break; 9756 case Incompatible: 9757 DiagKind = diag::err_typecheck_convert_incompatible; 9758 isInvalid = true; 9759 break; 9760 } 9761 9762 QualType FirstType, SecondType; 9763 switch (Action) { 9764 case AA_Assigning: 9765 case AA_Initializing: 9766 // The destination type comes first. 9767 FirstType = DstType; 9768 SecondType = SrcType; 9769 break; 9770 9771 case AA_Returning: 9772 case AA_Passing: 9773 case AA_Converting: 9774 case AA_Sending: 9775 case AA_Casting: 9776 // The source type comes first. 9777 FirstType = SrcType; 9778 SecondType = DstType; 9779 break; 9780 } 9781 9782 Diag(Loc, DiagKind) << FirstType << SecondType << Action 9783 << SrcExpr->getSourceRange() << Hint; 9784 if (Complained) 9785 *Complained = true; 9786 return isInvalid; 9787} 9788 9789bool Sema::VerifyIntegerConstantExpression(const Expr *E, llvm::APSInt *Result){ 9790 llvm::APSInt ICEResult; 9791 if (E->isIntegerConstantExpr(ICEResult, Context)) { 9792 if (Result) 9793 *Result = ICEResult; 9794 return false; 9795 } 9796 9797 Expr::EvalResult EvalResult; 9798 9799 if (!E->Evaluate(EvalResult, Context) || !EvalResult.Val.isInt() || 9800 EvalResult.HasSideEffects) { 9801 Diag(E->getExprLoc(), diag::err_expr_not_ice) << E->getSourceRange(); 9802 9803 if (EvalResult.Diag) { 9804 // We only show the note if it's not the usual "invalid subexpression" 9805 // or if it's actually in a subexpression. 9806 if (EvalResult.Diag != diag::note_invalid_subexpr_in_ice || 9807 E->IgnoreParens() != EvalResult.DiagExpr->IgnoreParens()) 9808 Diag(EvalResult.DiagLoc, EvalResult.Diag); 9809 } 9810 9811 return true; 9812 } 9813 9814 Diag(E->getExprLoc(), diag::ext_expr_not_ice) << 9815 E->getSourceRange(); 9816 9817 if (EvalResult.Diag && 9818 Diags.getDiagnosticLevel(diag::ext_expr_not_ice, EvalResult.DiagLoc) 9819 != Diagnostic::Ignored) 9820 Diag(EvalResult.DiagLoc, EvalResult.Diag); 9821 9822 if (Result) 9823 *Result = EvalResult.Val.getInt(); 9824 return false; 9825} 9826 9827void 9828Sema::PushExpressionEvaluationContext(ExpressionEvaluationContext NewContext) { 9829 ExprEvalContexts.push_back( 9830 ExpressionEvaluationContextRecord(NewContext, ExprTemporaries.size())); 9831} 9832 9833void 9834Sema::PopExpressionEvaluationContext() { 9835 // Pop the current expression evaluation context off the stack. 9836 ExpressionEvaluationContextRecord Rec = ExprEvalContexts.back(); 9837 ExprEvalContexts.pop_back(); 9838 9839 if (Rec.Context == PotentiallyPotentiallyEvaluated) { 9840 if (Rec.PotentiallyReferenced) { 9841 // Mark any remaining declarations in the current position of the stack 9842 // as "referenced". If they were not meant to be referenced, semantic 9843 // analysis would have eliminated them (e.g., in ActOnCXXTypeId). 9844 for (PotentiallyReferencedDecls::iterator 9845 I = Rec.PotentiallyReferenced->begin(), 9846 IEnd = Rec.PotentiallyReferenced->end(); 9847 I != IEnd; ++I) 9848 MarkDeclarationReferenced(I->first, I->second); 9849 } 9850 9851 if (Rec.PotentiallyDiagnosed) { 9852 // Emit any pending diagnostics. 9853 for (PotentiallyEmittedDiagnostics::iterator 9854 I = Rec.PotentiallyDiagnosed->begin(), 9855 IEnd = Rec.PotentiallyDiagnosed->end(); 9856 I != IEnd; ++I) 9857 Diag(I->first, I->second); 9858 } 9859 } 9860 9861 // When are coming out of an unevaluated context, clear out any 9862 // temporaries that we may have created as part of the evaluation of 9863 // the expression in that context: they aren't relevant because they 9864 // will never be constructed. 9865 if (Rec.Context == Unevaluated && 9866 ExprTemporaries.size() > Rec.NumTemporaries) 9867 ExprTemporaries.erase(ExprTemporaries.begin() + Rec.NumTemporaries, 9868 ExprTemporaries.end()); 9869 9870 // Destroy the popped expression evaluation record. 9871 Rec.Destroy(); 9872} 9873 9874/// \brief Note that the given declaration was referenced in the source code. 9875/// 9876/// This routine should be invoke whenever a given declaration is referenced 9877/// in the source code, and where that reference occurred. If this declaration 9878/// reference means that the the declaration is used (C++ [basic.def.odr]p2, 9879/// C99 6.9p3), then the declaration will be marked as used. 9880/// 9881/// \param Loc the location where the declaration was referenced. 9882/// 9883/// \param D the declaration that has been referenced by the source code. 9884void Sema::MarkDeclarationReferenced(SourceLocation Loc, Decl *D) { 9885 assert(D && "No declaration?"); 9886 9887 D->setReferenced(); 9888 9889 if (D->isUsed(false)) 9890 return; 9891 9892 // Mark a parameter or variable declaration "used", regardless of whether we're in a 9893 // template or not. The reason for this is that unevaluated expressions 9894 // (e.g. (void)sizeof()) constitute a use for warning purposes (-Wunused-variables and 9895 // -Wunused-parameters) 9896 if (isa<ParmVarDecl>(D) || 9897 (isa<VarDecl>(D) && D->getDeclContext()->isFunctionOrMethod())) { 9898 D->setUsed(); 9899 return; 9900 } 9901 9902 if (!isa<VarDecl>(D) && !isa<FunctionDecl>(D)) 9903 return; 9904 9905 // Do not mark anything as "used" within a dependent context; wait for 9906 // an instantiation. 9907 if (CurContext->isDependentContext()) 9908 return; 9909 9910 switch (ExprEvalContexts.back().Context) { 9911 case Unevaluated: 9912 // We are in an expression that is not potentially evaluated; do nothing. 9913 return; 9914 9915 case PotentiallyEvaluated: 9916 // We are in a potentially-evaluated expression, so this declaration is 9917 // "used"; handle this below. 9918 break; 9919 9920 case PotentiallyPotentiallyEvaluated: 9921 // We are in an expression that may be potentially evaluated; queue this 9922 // declaration reference until we know whether the expression is 9923 // potentially evaluated. 9924 ExprEvalContexts.back().addReferencedDecl(Loc, D); 9925 return; 9926 9927 case PotentiallyEvaluatedIfUsed: 9928 // Referenced declarations will only be used if the construct in the 9929 // containing expression is used. 9930 return; 9931 } 9932 9933 // Note that this declaration has been used. 9934 if (CXXConstructorDecl *Constructor = dyn_cast<CXXConstructorDecl>(D)) { 9935 unsigned TypeQuals; 9936 if (Constructor->isImplicit() && Constructor->isDefaultConstructor()) { 9937 if (Constructor->getParent()->hasTrivialConstructor()) 9938 return; 9939 if (!Constructor->isUsed(false)) 9940 DefineImplicitDefaultConstructor(Loc, Constructor); 9941 } else if (Constructor->isImplicit() && 9942 Constructor->isCopyConstructor(TypeQuals)) { 9943 if (!Constructor->isUsed(false)) 9944 DefineImplicitCopyConstructor(Loc, Constructor, TypeQuals); 9945 } 9946 9947 MarkVTableUsed(Loc, Constructor->getParent()); 9948 } else if (CXXDestructorDecl *Destructor = dyn_cast<CXXDestructorDecl>(D)) { 9949 if (Destructor->isImplicit() && !Destructor->isUsed(false)) 9950 DefineImplicitDestructor(Loc, Destructor); 9951 if (Destructor->isVirtual()) 9952 MarkVTableUsed(Loc, Destructor->getParent()); 9953 } else if (CXXMethodDecl *MethodDecl = dyn_cast<CXXMethodDecl>(D)) { 9954 if (MethodDecl->isImplicit() && MethodDecl->isOverloadedOperator() && 9955 MethodDecl->getOverloadedOperator() == OO_Equal) { 9956 if (!MethodDecl->isUsed(false)) 9957 DefineImplicitCopyAssignment(Loc, MethodDecl); 9958 } else if (MethodDecl->isVirtual()) 9959 MarkVTableUsed(Loc, MethodDecl->getParent()); 9960 } 9961 if (FunctionDecl *Function = dyn_cast<FunctionDecl>(D)) { 9962 // Recursive functions should be marked when used from another function. 9963 if (CurContext == Function) return; 9964 9965 // Implicit instantiation of function templates and member functions of 9966 // class templates. 9967 if (Function->isImplicitlyInstantiable()) { 9968 bool AlreadyInstantiated = false; 9969 if (FunctionTemplateSpecializationInfo *SpecInfo 9970 = Function->getTemplateSpecializationInfo()) { 9971 if (SpecInfo->getPointOfInstantiation().isInvalid()) 9972 SpecInfo->setPointOfInstantiation(Loc); 9973 else if (SpecInfo->getTemplateSpecializationKind() 9974 == TSK_ImplicitInstantiation) 9975 AlreadyInstantiated = true; 9976 } else if (MemberSpecializationInfo *MSInfo 9977 = Function->getMemberSpecializationInfo()) { 9978 if (MSInfo->getPointOfInstantiation().isInvalid()) 9979 MSInfo->setPointOfInstantiation(Loc); 9980 else if (MSInfo->getTemplateSpecializationKind() 9981 == TSK_ImplicitInstantiation) 9982 AlreadyInstantiated = true; 9983 } 9984 9985 if (!AlreadyInstantiated) { 9986 if (isa<CXXRecordDecl>(Function->getDeclContext()) && 9987 cast<CXXRecordDecl>(Function->getDeclContext())->isLocalClass()) 9988 PendingLocalImplicitInstantiations.push_back(std::make_pair(Function, 9989 Loc)); 9990 else 9991 PendingInstantiations.push_back(std::make_pair(Function, Loc)); 9992 } 9993 } else { 9994 // Walk redefinitions, as some of them may be instantiable. 9995 for (FunctionDecl::redecl_iterator i(Function->redecls_begin()), 9996 e(Function->redecls_end()); i != e; ++i) { 9997 if (!i->isUsed(false) && i->isImplicitlyInstantiable()) 9998 MarkDeclarationReferenced(Loc, *i); 9999 } 10000 } 10001 10002 // Keep track of used but undefined functions. 10003 if (!Function->isPure() && !Function->hasBody() && 10004 Function->getLinkage() != ExternalLinkage) { 10005 SourceLocation &old = UndefinedInternals[Function->getCanonicalDecl()]; 10006 if (old.isInvalid()) old = Loc; 10007 } 10008 10009 Function->setUsed(true); 10010 return; 10011 } 10012 10013 if (VarDecl *Var = dyn_cast<VarDecl>(D)) { 10014 // Implicit instantiation of static data members of class templates. 10015 if (Var->isStaticDataMember() && 10016 Var->getInstantiatedFromStaticDataMember()) { 10017 MemberSpecializationInfo *MSInfo = Var->getMemberSpecializationInfo(); 10018 assert(MSInfo && "Missing member specialization information?"); 10019 if (MSInfo->getPointOfInstantiation().isInvalid() && 10020 MSInfo->getTemplateSpecializationKind()== TSK_ImplicitInstantiation) { 10021 MSInfo->setPointOfInstantiation(Loc); 10022 PendingInstantiations.push_back(std::make_pair(Var, Loc)); 10023 } 10024 } 10025 10026 // Keep track of used but undefined variables. We make a hole in 10027 // the warning for static const data members with in-line 10028 // initializers. 10029 if (Var->hasDefinition() == VarDecl::DeclarationOnly 10030 && Var->getLinkage() != ExternalLinkage 10031 && !(Var->isStaticDataMember() && Var->hasInit())) { 10032 SourceLocation &old = UndefinedInternals[Var->getCanonicalDecl()]; 10033 if (old.isInvalid()) old = Loc; 10034 } 10035 10036 D->setUsed(true); 10037 return; 10038 } 10039} 10040 10041namespace { 10042 // Mark all of the declarations referenced 10043 // FIXME: Not fully implemented yet! We need to have a better understanding 10044 // of when we're entering 10045 class MarkReferencedDecls : public RecursiveASTVisitor<MarkReferencedDecls> { 10046 Sema &S; 10047 SourceLocation Loc; 10048 10049 public: 10050 typedef RecursiveASTVisitor<MarkReferencedDecls> Inherited; 10051 10052 MarkReferencedDecls(Sema &S, SourceLocation Loc) : S(S), Loc(Loc) { } 10053 10054 bool TraverseTemplateArgument(const TemplateArgument &Arg); 10055 bool TraverseRecordType(RecordType *T); 10056 }; 10057} 10058 10059bool MarkReferencedDecls::TraverseTemplateArgument( 10060 const TemplateArgument &Arg) { 10061 if (Arg.getKind() == TemplateArgument::Declaration) { 10062 S.MarkDeclarationReferenced(Loc, Arg.getAsDecl()); 10063 } 10064 10065 return Inherited::TraverseTemplateArgument(Arg); 10066} 10067 10068bool MarkReferencedDecls::TraverseRecordType(RecordType *T) { 10069 if (ClassTemplateSpecializationDecl *Spec 10070 = dyn_cast<ClassTemplateSpecializationDecl>(T->getDecl())) { 10071 const TemplateArgumentList &Args = Spec->getTemplateArgs(); 10072 return TraverseTemplateArguments(Args.data(), Args.size()); 10073 } 10074 10075 return true; 10076} 10077 10078void Sema::MarkDeclarationsReferencedInType(SourceLocation Loc, QualType T) { 10079 MarkReferencedDecls Marker(*this, Loc); 10080 Marker.TraverseType(Context.getCanonicalType(T)); 10081} 10082 10083namespace { 10084 /// \brief Helper class that marks all of the declarations referenced by 10085 /// potentially-evaluated subexpressions as "referenced". 10086 class EvaluatedExprMarker : public EvaluatedExprVisitor<EvaluatedExprMarker> { 10087 Sema &S; 10088 10089 public: 10090 typedef EvaluatedExprVisitor<EvaluatedExprMarker> Inherited; 10091 10092 explicit EvaluatedExprMarker(Sema &S) : Inherited(S.Context), S(S) { } 10093 10094 void VisitDeclRefExpr(DeclRefExpr *E) { 10095 S.MarkDeclarationReferenced(E->getLocation(), E->getDecl()); 10096 } 10097 10098 void VisitMemberExpr(MemberExpr *E) { 10099 S.MarkDeclarationReferenced(E->getMemberLoc(), E->getMemberDecl()); 10100 Inherited::VisitMemberExpr(E); 10101 } 10102 10103 void VisitCXXNewExpr(CXXNewExpr *E) { 10104 if (E->getConstructor()) 10105 S.MarkDeclarationReferenced(E->getLocStart(), E->getConstructor()); 10106 if (E->getOperatorNew()) 10107 S.MarkDeclarationReferenced(E->getLocStart(), E->getOperatorNew()); 10108 if (E->getOperatorDelete()) 10109 S.MarkDeclarationReferenced(E->getLocStart(), E->getOperatorDelete()); 10110 Inherited::VisitCXXNewExpr(E); 10111 } 10112 10113 void VisitCXXDeleteExpr(CXXDeleteExpr *E) { 10114 if (E->getOperatorDelete()) 10115 S.MarkDeclarationReferenced(E->getLocStart(), E->getOperatorDelete()); 10116 QualType Destroyed = S.Context.getBaseElementType(E->getDestroyedType()); 10117 if (const RecordType *DestroyedRec = Destroyed->getAs<RecordType>()) { 10118 CXXRecordDecl *Record = cast<CXXRecordDecl>(DestroyedRec->getDecl()); 10119 S.MarkDeclarationReferenced(E->getLocStart(), 10120 S.LookupDestructor(Record)); 10121 } 10122 10123 Inherited::VisitCXXDeleteExpr(E); 10124 } 10125 10126 void VisitCXXConstructExpr(CXXConstructExpr *E) { 10127 S.MarkDeclarationReferenced(E->getLocStart(), E->getConstructor()); 10128 Inherited::VisitCXXConstructExpr(E); 10129 } 10130 10131 void VisitBlockDeclRefExpr(BlockDeclRefExpr *E) { 10132 S.MarkDeclarationReferenced(E->getLocation(), E->getDecl()); 10133 } 10134 10135 void VisitCXXDefaultArgExpr(CXXDefaultArgExpr *E) { 10136 Visit(E->getExpr()); 10137 } 10138 }; 10139} 10140 10141/// \brief Mark any declarations that appear within this expression or any 10142/// potentially-evaluated subexpressions as "referenced". 10143void Sema::MarkDeclarationsReferencedInExpr(Expr *E) { 10144 EvaluatedExprMarker(*this).Visit(E); 10145} 10146 10147/// \brief Emit a diagnostic that describes an effect on the run-time behavior 10148/// of the program being compiled. 10149/// 10150/// This routine emits the given diagnostic when the code currently being 10151/// type-checked is "potentially evaluated", meaning that there is a 10152/// possibility that the code will actually be executable. Code in sizeof() 10153/// expressions, code used only during overload resolution, etc., are not 10154/// potentially evaluated. This routine will suppress such diagnostics or, 10155/// in the absolutely nutty case of potentially potentially evaluated 10156/// expressions (C++ typeid), queue the diagnostic to potentially emit it 10157/// later. 10158/// 10159/// This routine should be used for all diagnostics that describe the run-time 10160/// behavior of a program, such as passing a non-POD value through an ellipsis. 10161/// Failure to do so will likely result in spurious diagnostics or failures 10162/// during overload resolution or within sizeof/alignof/typeof/typeid. 10163bool Sema::DiagRuntimeBehavior(SourceLocation Loc, const Stmt *stmt, 10164 const PartialDiagnostic &PD) { 10165 switch (ExprEvalContexts.back().Context ) { 10166 case Unevaluated: 10167 // The argument will never be evaluated, so don't complain. 10168 break; 10169 10170 case PotentiallyEvaluated: 10171 case PotentiallyEvaluatedIfUsed: 10172 if (stmt && getCurFunctionOrMethodDecl()) { 10173 FunctionScopes.back()->PossiblyUnreachableDiags. 10174 push_back(sema::PossiblyUnreachableDiag(PD, Loc, stmt)); 10175 } 10176 else 10177 Diag(Loc, PD); 10178 10179 return true; 10180 10181 case PotentiallyPotentiallyEvaluated: 10182 ExprEvalContexts.back().addDiagnostic(Loc, PD); 10183 break; 10184 } 10185 10186 return false; 10187} 10188 10189bool Sema::CheckCallReturnType(QualType ReturnType, SourceLocation Loc, 10190 CallExpr *CE, FunctionDecl *FD) { 10191 if (ReturnType->isVoidType() || !ReturnType->isIncompleteType()) 10192 return false; 10193 10194 PartialDiagnostic Note = 10195 FD ? PDiag(diag::note_function_with_incomplete_return_type_declared_here) 10196 << FD->getDeclName() : PDiag(); 10197 SourceLocation NoteLoc = FD ? FD->getLocation() : SourceLocation(); 10198 10199 if (RequireCompleteType(Loc, ReturnType, 10200 FD ? 10201 PDiag(diag::err_call_function_incomplete_return) 10202 << CE->getSourceRange() << FD->getDeclName() : 10203 PDiag(diag::err_call_incomplete_return) 10204 << CE->getSourceRange(), 10205 std::make_pair(NoteLoc, Note))) 10206 return true; 10207 10208 return false; 10209} 10210 10211// Diagnose the s/=/==/ and s/\|=/!=/ typos. Note that adding parentheses 10212// will prevent this condition from triggering, which is what we want. 10213void Sema::DiagnoseAssignmentAsCondition(Expr *E) { 10214 SourceLocation Loc; 10215 10216 unsigned diagnostic = diag::warn_condition_is_assignment; 10217 bool IsOrAssign = false; 10218 10219 if (isa<BinaryOperator>(E)) { 10220 BinaryOperator *Op = cast<BinaryOperator>(E); 10221 if (Op->getOpcode() != BO_Assign && Op->getOpcode() != BO_OrAssign) 10222 return; 10223 10224 IsOrAssign = Op->getOpcode() == BO_OrAssign; 10225 10226 // Greylist some idioms by putting them into a warning subcategory. 10227 if (ObjCMessageExpr *ME 10228 = dyn_cast<ObjCMessageExpr>(Op->getRHS()->IgnoreParenCasts())) { 10229 Selector Sel = ME->getSelector(); 10230 10231 // self = [<foo> init...] 10232 if (isSelfExpr(Op->getLHS()) && Sel.getNameForSlot(0).startswith("init")) 10233 diagnostic = diag::warn_condition_is_idiomatic_assignment; 10234 10235 // <foo> = [<bar> nextObject] 10236 else if (Sel.isUnarySelector() && Sel.getNameForSlot(0) == "nextObject") 10237 diagnostic = diag::warn_condition_is_idiomatic_assignment; 10238 } 10239 10240 Loc = Op->getOperatorLoc(); 10241 } else if (isa<CXXOperatorCallExpr>(E)) { 10242 CXXOperatorCallExpr *Op = cast<CXXOperatorCallExpr>(E); 10243 if (Op->getOperator() != OO_Equal && Op->getOperator() != OO_PipeEqual) 10244 return; 10245 10246 IsOrAssign = Op->getOperator() == OO_PipeEqual; 10247 Loc = Op->getOperatorLoc(); 10248 } else { 10249 // Not an assignment. 10250 return; 10251 } 10252 10253 Diag(Loc, diagnostic) << E->getSourceRange(); 10254 10255 if (IsOrAssign) 10256 Diag(Loc, diag::note_condition_or_assign_to_comparison) 10257 << FixItHint::CreateReplacement(Loc, "!="); 10258 else 10259 Diag(Loc, diag::note_condition_assign_to_comparison) 10260 << FixItHint::CreateReplacement(Loc, "=="); 10261 10262 SourceLocation Open = E->getSourceRange().getBegin(); 10263 SourceLocation Close = PP.getLocForEndOfToken(E->getSourceRange().getEnd()); 10264 Diag(Loc, diag::note_condition_assign_silence) 10265 << FixItHint::CreateInsertion(Open, "(") 10266 << FixItHint::CreateInsertion(Close, ")"); 10267} 10268 10269/// \brief Redundant parentheses over an equality comparison can indicate 10270/// that the user intended an assignment used as condition. 10271void Sema::DiagnoseEqualityWithExtraParens(ParenExpr *parenE) { 10272 // Don't warn if the parens came from a macro. 10273 SourceLocation parenLoc = parenE->getLocStart(); 10274 if (parenLoc.isInvalid() || parenLoc.isMacroID()) 10275 return; 10276 // Don't warn for dependent expressions. 10277 if (parenE->isTypeDependent()) 10278 return; 10279 10280 Expr *E = parenE->IgnoreParens(); 10281 10282 if (BinaryOperator *opE = dyn_cast<BinaryOperator>(E)) 10283 if (opE->getOpcode() == BO_EQ && 10284 opE->getLHS()->IgnoreParenImpCasts()->isModifiableLvalue(Context) 10285 == Expr::MLV_Valid) { 10286 SourceLocation Loc = opE->getOperatorLoc(); 10287 10288 Diag(Loc, diag::warn_equality_with_extra_parens) << E->getSourceRange(); 10289 Diag(Loc, diag::note_equality_comparison_to_assign) 10290 << FixItHint::CreateReplacement(Loc, "="); 10291 Diag(Loc, diag::note_equality_comparison_silence) 10292 << FixItHint::CreateRemoval(parenE->getSourceRange().getBegin()) 10293 << FixItHint::CreateRemoval(parenE->getSourceRange().getEnd()); 10294 } 10295} 10296 10297ExprResult Sema::CheckBooleanCondition(Expr *E, SourceLocation Loc) { 10298 DiagnoseAssignmentAsCondition(E); 10299 if (ParenExpr *parenE = dyn_cast<ParenExpr>(E)) 10300 DiagnoseEqualityWithExtraParens(parenE); 10301 10302 if (!E->isTypeDependent()) { 10303 if (E->isBoundMemberFunction(Context)) { 10304 Diag(E->getLocStart(), diag::err_invalid_use_of_bound_member_func) 10305 << E->getSourceRange(); 10306 return ExprError(); 10307 } 10308 10309 if (getLangOptions().CPlusPlus) 10310 return CheckCXXBooleanCondition(E); // C++ 6.4p4 10311 10312 ExprResult ERes = DefaultFunctionArrayLvalueConversion(E); 10313 if (ERes.isInvalid()) 10314 return ExprError(); 10315 E = ERes.take(); 10316 10317 QualType T = E->getType(); 10318 if (!T->isScalarType()) { // C99 6.8.4.1p1 10319 Diag(Loc, diag::err_typecheck_statement_requires_scalar) 10320 << T << E->getSourceRange(); 10321 return ExprError(); 10322 } 10323 } 10324 10325 return Owned(E); 10326} 10327 10328ExprResult Sema::ActOnBooleanCondition(Scope *S, SourceLocation Loc, 10329 Expr *Sub) { 10330 if (!Sub) 10331 return ExprError(); 10332 10333 return CheckBooleanCondition(Sub, Loc); 10334} 10335 10336namespace { 10337 /// A visitor for rebuilding a call to an __unknown_any expression 10338 /// to have an appropriate type. 10339 struct RebuildUnknownAnyFunction 10340 : StmtVisitor<RebuildUnknownAnyFunction, ExprResult> { 10341 10342 Sema &S; 10343 10344 RebuildUnknownAnyFunction(Sema &S) : S(S) {} 10345 10346 ExprResult VisitStmt(Stmt *S) { 10347 llvm_unreachable("unexpected statement!"); 10348 return ExprError(); 10349 } 10350 10351 ExprResult VisitExpr(Expr *expr) { 10352 S.Diag(expr->getExprLoc(), diag::err_unsupported_unknown_any_call) 10353 << expr->getSourceRange(); 10354 return ExprError(); 10355 } 10356 10357 /// Rebuild an expression which simply semantically wraps another 10358 /// expression which it shares the type and value kind of. 10359 template <class T> ExprResult rebuildSugarExpr(T *expr) { 10360 ExprResult subResult = Visit(expr->getSubExpr()); 10361 if (subResult.isInvalid()) return ExprError(); 10362 10363 Expr *subExpr = subResult.take(); 10364 expr->setSubExpr(subExpr); 10365 expr->setType(subExpr->getType()); 10366 expr->setValueKind(subExpr->getValueKind()); 10367 assert(expr->getObjectKind() == OK_Ordinary); 10368 return expr; 10369 } 10370 10371 ExprResult VisitParenExpr(ParenExpr *paren) { 10372 return rebuildSugarExpr(paren); 10373 } 10374 10375 ExprResult VisitUnaryExtension(UnaryOperator *op) { 10376 return rebuildSugarExpr(op); 10377 } 10378 10379 ExprResult VisitUnaryAddrOf(UnaryOperator *op) { 10380 ExprResult subResult = Visit(op->getSubExpr()); 10381 if (subResult.isInvalid()) return ExprError(); 10382 10383 Expr *subExpr = subResult.take(); 10384 op->setSubExpr(subExpr); 10385 op->setType(S.Context.getPointerType(subExpr->getType())); 10386 assert(op->getValueKind() == VK_RValue); 10387 assert(op->getObjectKind() == OK_Ordinary); 10388 return op; 10389 } 10390 10391 ExprResult resolveDecl(Expr *expr, ValueDecl *decl) { 10392 if (!isa<FunctionDecl>(decl)) return VisitExpr(expr); 10393 10394 expr->setType(decl->getType()); 10395 10396 assert(expr->getValueKind() == VK_RValue); 10397 if (S.getLangOptions().CPlusPlus && 10398 !(isa<CXXMethodDecl>(decl) && 10399 cast<CXXMethodDecl>(decl)->isInstance())) 10400 expr->setValueKind(VK_LValue); 10401 10402 return expr; 10403 } 10404 10405 ExprResult VisitMemberExpr(MemberExpr *mem) { 10406 return resolveDecl(mem, mem->getMemberDecl()); 10407 } 10408 10409 ExprResult VisitDeclRefExpr(DeclRefExpr *ref) { 10410 return resolveDecl(ref, ref->getDecl()); 10411 } 10412 }; 10413} 10414 10415/// Given a function expression of unknown-any type, try to rebuild it 10416/// to have a function type. 10417static ExprResult rebuildUnknownAnyFunction(Sema &S, Expr *fn) { 10418 ExprResult result = RebuildUnknownAnyFunction(S).Visit(fn); 10419 if (result.isInvalid()) return ExprError(); 10420 return S.DefaultFunctionArrayConversion(result.take()); 10421} 10422 10423namespace { 10424 /// A visitor for rebuilding an expression of type __unknown_anytype 10425 /// into one which resolves the type directly on the referring 10426 /// expression. Strict preservation of the original source 10427 /// structure is not a goal. 10428 struct RebuildUnknownAnyExpr 10429 : StmtVisitor<RebuildUnknownAnyExpr, ExprResult> { 10430 10431 Sema &S; 10432 10433 /// The current destination type. 10434 QualType DestType; 10435 10436 RebuildUnknownAnyExpr(Sema &S, QualType castType) 10437 : S(S), DestType(castType) {} 10438 10439 ExprResult VisitStmt(Stmt *S) { 10440 llvm_unreachable("unexpected statement!"); 10441 return ExprError(); 10442 } 10443 10444 ExprResult VisitExpr(Expr *expr) { 10445 S.Diag(expr->getExprLoc(), diag::err_unsupported_unknown_any_expr) 10446 << expr->getSourceRange(); 10447 return ExprError(); 10448 } 10449 10450 ExprResult VisitCallExpr(CallExpr *call); 10451 ExprResult VisitObjCMessageExpr(ObjCMessageExpr *message); 10452 10453 /// Rebuild an expression which simply semantically wraps another 10454 /// expression which it shares the type and value kind of. 10455 template <class T> ExprResult rebuildSugarExpr(T *expr) { 10456 ExprResult subResult = Visit(expr->getSubExpr()); 10457 if (subResult.isInvalid()) return ExprError(); 10458 Expr *subExpr = subResult.take(); 10459 expr->setSubExpr(subExpr); 10460 expr->setType(subExpr->getType()); 10461 expr->setValueKind(subExpr->getValueKind()); 10462 assert(expr->getObjectKind() == OK_Ordinary); 10463 return expr; 10464 } 10465 10466 ExprResult VisitParenExpr(ParenExpr *paren) { 10467 return rebuildSugarExpr(paren); 10468 } 10469 10470 ExprResult VisitUnaryExtension(UnaryOperator *op) { 10471 return rebuildSugarExpr(op); 10472 } 10473 10474 ExprResult VisitUnaryAddrOf(UnaryOperator *op) { 10475 const PointerType *ptr = DestType->getAs<PointerType>(); 10476 if (!ptr) { 10477 S.Diag(op->getOperatorLoc(), diag::err_unknown_any_addrof) 10478 << op->getSourceRange(); 10479 return ExprError(); 10480 } 10481 assert(op->getValueKind() == VK_RValue); 10482 assert(op->getObjectKind() == OK_Ordinary); 10483 op->setType(DestType); 10484 10485 // Build the sub-expression as if it were an object of the pointee type. 10486 DestType = ptr->getPointeeType(); 10487 ExprResult subResult = Visit(op->getSubExpr()); 10488 if (subResult.isInvalid()) return ExprError(); 10489 op->setSubExpr(subResult.take()); 10490 return op; 10491 } 10492 10493 ExprResult VisitImplicitCastExpr(ImplicitCastExpr *ice); 10494 10495 ExprResult resolveDecl(Expr *expr, ValueDecl *decl); 10496 10497 ExprResult VisitMemberExpr(MemberExpr *mem) { 10498 return resolveDecl(mem, mem->getMemberDecl()); 10499 } 10500 10501 ExprResult VisitDeclRefExpr(DeclRefExpr *ref) { 10502 return resolveDecl(ref, ref->getDecl()); 10503 } 10504 }; 10505} 10506 10507/// Rebuilds a call expression which yielded __unknown_anytype. 10508ExprResult RebuildUnknownAnyExpr::VisitCallExpr(CallExpr *call) { 10509 Expr *callee = call->getCallee(); 10510 10511 enum FnKind { 10512 FK_Function, 10513 FK_FunctionPointer, 10514 FK_BlockPointer 10515 }; 10516 10517 FnKind kind; 10518 QualType type = callee->getType(); 10519 if (type->isFunctionType()) { 10520 assert(isa<CXXMemberCallExpr>(call) || isa<CXXOperatorCallExpr>(call)); 10521 kind = FK_Function; 10522 } else if (const PointerType *ptr = type->getAs<PointerType>()) { 10523 type = ptr->getPointeeType(); 10524 kind = FK_FunctionPointer; 10525 } else { 10526 type = type->castAs<BlockPointerType>()->getPointeeType(); 10527 kind = FK_BlockPointer; 10528 } 10529 const FunctionType *fnType = type->castAs<FunctionType>(); 10530 10531 // Verify that this is a legal result type of a function. 10532 if (DestType->isArrayType() || DestType->isFunctionType()) { 10533 unsigned diagID = diag::err_func_returning_array_function; 10534 if (kind == FK_BlockPointer) 10535 diagID = diag::err_block_returning_array_function; 10536 10537 S.Diag(call->getExprLoc(), diagID) 10538 << DestType->isFunctionType() << DestType; 10539 return ExprError(); 10540 } 10541 10542 // Otherwise, go ahead and set DestType as the call's result. 10543 call->setType(DestType.getNonLValueExprType(S.Context)); 10544 call->setValueKind(Expr::getValueKindForType(DestType)); 10545 assert(call->getObjectKind() == OK_Ordinary); 10546 10547 // Rebuild the function type, replacing the result type with DestType. 10548 if (const FunctionProtoType *proto = dyn_cast<FunctionProtoType>(fnType)) 10549 DestType = S.Context.getFunctionType(DestType, 10550 proto->arg_type_begin(), 10551 proto->getNumArgs(), 10552 proto->getExtProtoInfo()); 10553 else 10554 DestType = S.Context.getFunctionNoProtoType(DestType, 10555 fnType->getExtInfo()); 10556 10557 // Rebuild the appropriate pointer-to-function type. 10558 switch (kind) { 10559 case FK_Function: 10560 // Nothing to do. 10561 break; 10562 10563 case FK_FunctionPointer: 10564 DestType = S.Context.getPointerType(DestType); 10565 break; 10566 10567 case FK_BlockPointer: 10568 DestType = S.Context.getBlockPointerType(DestType); 10569 break; 10570 } 10571 10572 // Finally, we can recurse. 10573 ExprResult calleeResult = Visit(callee); 10574 if (!calleeResult.isUsable()) return ExprError(); 10575 call->setCallee(calleeResult.take()); 10576 10577 // Bind a temporary if necessary. 10578 return S.MaybeBindToTemporary(call); 10579} 10580 10581ExprResult RebuildUnknownAnyExpr::VisitObjCMessageExpr(ObjCMessageExpr *msg) { 10582 ObjCMethodDecl *method = msg->getMethodDecl(); 10583 assert(method && "__unknown_anytype message without result type?"); 10584 10585 // Verify that this is a legal result type of a call. 10586 if (DestType->isArrayType() || DestType->isFunctionType()) { 10587 S.Diag(msg->getExprLoc(), diag::err_func_returning_array_function) 10588 << DestType->isFunctionType() << DestType; 10589 return ExprError(); 10590 } 10591 10592 assert(method->getResultType() == S.Context.UnknownAnyTy); 10593 method->setResultType(DestType); 10594 10595 // Change the type of the message. 10596 msg->setType(DestType.getNonReferenceType()); 10597 msg->setValueKind(Expr::getValueKindForType(DestType)); 10598 10599 return S.MaybeBindToTemporary(msg); 10600} 10601 10602ExprResult RebuildUnknownAnyExpr::VisitImplicitCastExpr(ImplicitCastExpr *ice) { 10603 // The only case we should ever see here is a function-to-pointer decay. 10604 assert(ice->getCastKind() == CK_FunctionToPointerDecay); 10605 assert(ice->getValueKind() == VK_RValue); 10606 assert(ice->getObjectKind() == OK_Ordinary); 10607 10608 ice->setType(DestType); 10609 10610 // Rebuild the sub-expression as the pointee (function) type. 10611 DestType = DestType->castAs<PointerType>()->getPointeeType(); 10612 10613 ExprResult result = Visit(ice->getSubExpr()); 10614 if (!result.isUsable()) return ExprError(); 10615 10616 ice->setSubExpr(result.take()); 10617 return S.Owned(ice); 10618} 10619 10620ExprResult RebuildUnknownAnyExpr::resolveDecl(Expr *expr, ValueDecl *decl) { 10621 ExprValueKind valueKind = VK_LValue; 10622 QualType type = DestType; 10623 10624 // We know how to make this work for certain kinds of decls: 10625 10626 // - functions 10627 if (FunctionDecl *fn = dyn_cast<FunctionDecl>(decl)) { 10628 if (CXXMethodDecl *method = dyn_cast<CXXMethodDecl>(fn)) 10629 if (method->isInstance()) valueKind = VK_RValue; 10630 10631 // This is true because FunctionDecls must always have function 10632 // type, so we can't be resolving the entire thing at once. 10633 assert(type->isFunctionType()); 10634 10635 // Function references aren't l-values in C. 10636 if (!S.getLangOptions().CPlusPlus) 10637 valueKind = VK_RValue; 10638 10639 // - variables 10640 } else if (isa<VarDecl>(decl)) { 10641 if (const ReferenceType *refTy = type->getAs<ReferenceType>()) { 10642 type = refTy->getPointeeType(); 10643 } else if (type->isFunctionType()) { 10644 S.Diag(expr->getExprLoc(), diag::err_unknown_any_var_function_type) 10645 << decl << expr->getSourceRange(); 10646 return ExprError(); 10647 } 10648 10649 // - nothing else 10650 } else { 10651 S.Diag(expr->getExprLoc(), diag::err_unsupported_unknown_any_decl) 10652 << decl << expr->getSourceRange(); 10653 return ExprError(); 10654 } 10655 10656 decl->setType(DestType); 10657 expr->setType(type); 10658 expr->setValueKind(valueKind); 10659 return S.Owned(expr); 10660} 10661 10662/// Check a cast of an unknown-any type. We intentionally only 10663/// trigger this for C-style casts. 10664ExprResult Sema::checkUnknownAnyCast(SourceRange typeRange, QualType castType, 10665 Expr *castExpr, CastKind &castKind, 10666 ExprValueKind &VK, CXXCastPath &path) { 10667 // Rewrite the casted expression from scratch. 10668 ExprResult result = RebuildUnknownAnyExpr(*this, castType).Visit(castExpr); 10669 if (!result.isUsable()) return ExprError(); 10670 10671 castExpr = result.take(); 10672 VK = castExpr->getValueKind(); 10673 castKind = CK_NoOp; 10674 10675 return castExpr; 10676} 10677 10678static ExprResult diagnoseUnknownAnyExpr(Sema &S, Expr *e) { 10679 Expr *orig = e; 10680 unsigned diagID = diag::err_uncasted_use_of_unknown_any; 10681 while (true) { 10682 e = e->IgnoreParenImpCasts(); 10683 if (CallExpr *call = dyn_cast<CallExpr>(e)) { 10684 e = call->getCallee(); 10685 diagID = diag::err_uncasted_call_of_unknown_any; 10686 } else { 10687 break; 10688 } 10689 } 10690 10691 SourceLocation loc; 10692 NamedDecl *d; 10693 if (DeclRefExpr *ref = dyn_cast<DeclRefExpr>(e)) { 10694 loc = ref->getLocation(); 10695 d = ref->getDecl(); 10696 } else if (MemberExpr *mem = dyn_cast<MemberExpr>(e)) { 10697 loc = mem->getMemberLoc(); 10698 d = mem->getMemberDecl(); 10699 } else if (ObjCMessageExpr *msg = dyn_cast<ObjCMessageExpr>(e)) { 10700 diagID = diag::err_uncasted_call_of_unknown_any; 10701 loc = msg->getSelectorLoc(); 10702 d = msg->getMethodDecl(); 10703 assert(d && "unknown method returning __unknown_any?"); 10704 } else { 10705 S.Diag(e->getExprLoc(), diag::err_unsupported_unknown_any_expr) 10706 << e->getSourceRange(); 10707 return ExprError(); 10708 } 10709 10710 S.Diag(loc, diagID) << d << orig->getSourceRange(); 10711 10712 // Never recoverable. 10713 return ExprError(); 10714} 10715 10716/// Check for operands with placeholder types and complain if found. 10717/// Returns true if there was an error and no recovery was possible. 10718ExprResult Sema::CheckPlaceholderExpr(Expr *E) { 10719 // Placeholder types are always *exactly* the appropriate builtin type. 10720 QualType type = E->getType(); 10721 10722 // Overloaded expressions. 10723 if (type == Context.OverloadTy) 10724 return ResolveAndFixSingleFunctionTemplateSpecialization(E, false, true, 10725 E->getSourceRange(), 10726 QualType(), 10727 diag::err_ovl_unresolvable); 10728 10729 // Expressions of unknown type. 10730 if (type == Context.UnknownAnyTy) 10731 return diagnoseUnknownAnyExpr(*this, E); 10732 10733 assert(!type->isPlaceholderType()); 10734 return Owned(E); 10735} 10736 10737bool Sema::CheckCaseExpression(Expr *expr) { 10738 if (expr->isTypeDependent()) 10739 return true; 10740 if (expr->isValueDependent() || expr->isIntegerConstantExpr(Context)) 10741 return expr->getType()->isIntegralOrEnumerationType(); 10742 return false; 10743} 10744