SemaExpr.cpp revision 3e9ea0b8cd7c4691d62e385245556be5fded58a7
1//===--- SemaExpr.cpp - Semantic Analysis for Expressions -----------------===// 2// 3// The LLVM Compiler Infrastructure 4// 5// This file is distributed under the University of Illinois Open Source 6// License. See LICENSE.TXT for details. 7// 8//===----------------------------------------------------------------------===// 9// 10// This file implements semantic analysis for expressions. 11// 12//===----------------------------------------------------------------------===// 13 14#include "clang/Sema/SemaInternal.h" 15#include "clang/Sema/Initialization.h" 16#include "clang/Sema/Lookup.h" 17#include "clang/Sema/AnalysisBasedWarnings.h" 18#include "clang/AST/ASTContext.h" 19#include "clang/AST/ASTMutationListener.h" 20#include "clang/AST/CXXInheritance.h" 21#include "clang/AST/DeclObjC.h" 22#include "clang/AST/DeclTemplate.h" 23#include "clang/AST/EvaluatedExprVisitor.h" 24#include "clang/AST/Expr.h" 25#include "clang/AST/ExprCXX.h" 26#include "clang/AST/ExprObjC.h" 27#include "clang/AST/RecursiveASTVisitor.h" 28#include "clang/AST/TypeLoc.h" 29#include "clang/Basic/PartialDiagnostic.h" 30#include "clang/Basic/SourceManager.h" 31#include "clang/Basic/TargetInfo.h" 32#include "clang/Lex/LiteralSupport.h" 33#include "clang/Lex/Preprocessor.h" 34#include "clang/Sema/DeclSpec.h" 35#include "clang/Sema/Designator.h" 36#include "clang/Sema/Scope.h" 37#include "clang/Sema/ScopeInfo.h" 38#include "clang/Sema/ParsedTemplate.h" 39#include "clang/Sema/SemaFixItUtils.h" 40#include "clang/Sema/Template.h" 41using namespace clang; 42using namespace sema; 43 44/// \brief Determine whether the use of this declaration is valid, without 45/// emitting diagnostics. 46bool Sema::CanUseDecl(NamedDecl *D) { 47 // See if this is an auto-typed variable whose initializer we are parsing. 48 if (ParsingInitForAutoVars.count(D)) 49 return false; 50 51 // See if this is a deleted function. 52 if (FunctionDecl *FD = dyn_cast<FunctionDecl>(D)) { 53 if (FD->isDeleted()) 54 return false; 55 } 56 57 // See if this function is unavailable. 58 if (D->getAvailability() == AR_Unavailable && 59 cast<Decl>(CurContext)->getAvailability() != AR_Unavailable) 60 return false; 61 62 return true; 63} 64 65AvailabilityResult 66Sema::DiagnoseAvailabilityOfDecl( 67 NamedDecl *D, SourceLocation Loc, 68 const ObjCInterfaceDecl *UnknownObjCClass) { 69 // See if this declaration is unavailable or deprecated. 70 std::string Message; 71 AvailabilityResult Result = D->getAvailability(&Message); 72 if (const EnumConstantDecl *ECD = dyn_cast<EnumConstantDecl>(D)) 73 if (Result == AR_Available) { 74 const DeclContext *DC = ECD->getDeclContext(); 75 if (const EnumDecl *TheEnumDecl = dyn_cast<EnumDecl>(DC)) 76 Result = TheEnumDecl->getAvailability(&Message); 77 } 78 79 switch (Result) { 80 case AR_Available: 81 case AR_NotYetIntroduced: 82 break; 83 84 case AR_Deprecated: 85 EmitDeprecationWarning(D, Message, Loc, UnknownObjCClass); 86 break; 87 88 case AR_Unavailable: 89 if (getCurContextAvailability() != AR_Unavailable) { 90 if (Message.empty()) { 91 if (!UnknownObjCClass) 92 Diag(Loc, diag::err_unavailable) << D->getDeclName(); 93 else 94 Diag(Loc, diag::warn_unavailable_fwdclass_message) 95 << D->getDeclName(); 96 } 97 else 98 Diag(Loc, diag::err_unavailable_message) 99 << D->getDeclName() << Message; 100 Diag(D->getLocation(), diag::note_unavailable_here) 101 << isa<FunctionDecl>(D) << false; 102 } 103 break; 104 } 105 return Result; 106} 107 108/// \brief Determine whether the use of this declaration is valid, and 109/// emit any corresponding diagnostics. 110/// 111/// This routine diagnoses various problems with referencing 112/// declarations that can occur when using a declaration. For example, 113/// it might warn if a deprecated or unavailable declaration is being 114/// used, or produce an error (and return true) if a C++0x deleted 115/// function is being used. 116/// 117/// \returns true if there was an error (this declaration cannot be 118/// referenced), false otherwise. 119/// 120bool Sema::DiagnoseUseOfDecl(NamedDecl *D, SourceLocation Loc, 121 const ObjCInterfaceDecl *UnknownObjCClass) { 122 if (getLangOptions().CPlusPlus && isa<FunctionDecl>(D)) { 123 // If there were any diagnostics suppressed by template argument deduction, 124 // emit them now. 125 llvm::DenseMap<Decl *, SmallVector<PartialDiagnosticAt, 1> >::iterator 126 Pos = SuppressedDiagnostics.find(D->getCanonicalDecl()); 127 if (Pos != SuppressedDiagnostics.end()) { 128 SmallVectorImpl<PartialDiagnosticAt> &Suppressed = Pos->second; 129 for (unsigned I = 0, N = Suppressed.size(); I != N; ++I) 130 Diag(Suppressed[I].first, Suppressed[I].second); 131 132 // Clear out the list of suppressed diagnostics, so that we don't emit 133 // them again for this specialization. However, we don't obsolete this 134 // entry from the table, because we want to avoid ever emitting these 135 // diagnostics again. 136 Suppressed.clear(); 137 } 138 } 139 140 // See if this is an auto-typed variable whose initializer we are parsing. 141 if (ParsingInitForAutoVars.count(D)) { 142 Diag(Loc, diag::err_auto_variable_cannot_appear_in_own_initializer) 143 << D->getDeclName(); 144 return true; 145 } 146 147 // See if this is a deleted function. 148 if (FunctionDecl *FD = dyn_cast<FunctionDecl>(D)) { 149 if (FD->isDeleted()) { 150 Diag(Loc, diag::err_deleted_function_use); 151 Diag(D->getLocation(), diag::note_unavailable_here) << 1 << true; 152 return true; 153 } 154 } 155 DiagnoseAvailabilityOfDecl(D, Loc, UnknownObjCClass); 156 157 // Warn if this is used but marked unused. 158 if (D->hasAttr<UnusedAttr>()) 159 Diag(Loc, diag::warn_used_but_marked_unused) << D->getDeclName(); 160 return false; 161} 162 163/// \brief Retrieve the message suffix that should be added to a 164/// diagnostic complaining about the given function being deleted or 165/// unavailable. 166std::string Sema::getDeletedOrUnavailableSuffix(const FunctionDecl *FD) { 167 // FIXME: C++0x implicitly-deleted special member functions could be 168 // detected here so that we could improve diagnostics to say, e.g., 169 // "base class 'A' had a deleted copy constructor". 170 if (FD->isDeleted()) 171 return std::string(); 172 173 std::string Message; 174 if (FD->getAvailability(&Message)) 175 return ": " + Message; 176 177 return std::string(); 178} 179 180/// DiagnoseSentinelCalls - This routine checks whether a call or 181/// message-send is to a declaration with the sentinel attribute, and 182/// if so, it checks that the requirements of the sentinel are 183/// satisfied. 184void Sema::DiagnoseSentinelCalls(NamedDecl *D, SourceLocation Loc, 185 Expr **args, unsigned numArgs) { 186 const SentinelAttr *attr = D->getAttr<SentinelAttr>(); 187 if (!attr) 188 return; 189 190 // The number of formal parameters of the declaration. 191 unsigned numFormalParams; 192 193 // The kind of declaration. This is also an index into a %select in 194 // the diagnostic. 195 enum CalleeType { CT_Function, CT_Method, CT_Block } calleeType; 196 197 if (ObjCMethodDecl *MD = dyn_cast<ObjCMethodDecl>(D)) { 198 numFormalParams = MD->param_size(); 199 calleeType = CT_Method; 200 } else if (FunctionDecl *FD = dyn_cast<FunctionDecl>(D)) { 201 numFormalParams = FD->param_size(); 202 calleeType = CT_Function; 203 } else if (isa<VarDecl>(D)) { 204 QualType type = cast<ValueDecl>(D)->getType(); 205 const FunctionType *fn = 0; 206 if (const PointerType *ptr = type->getAs<PointerType>()) { 207 fn = ptr->getPointeeType()->getAs<FunctionType>(); 208 if (!fn) return; 209 calleeType = CT_Function; 210 } else if (const BlockPointerType *ptr = type->getAs<BlockPointerType>()) { 211 fn = ptr->getPointeeType()->castAs<FunctionType>(); 212 calleeType = CT_Block; 213 } else { 214 return; 215 } 216 217 if (const FunctionProtoType *proto = dyn_cast<FunctionProtoType>(fn)) { 218 numFormalParams = proto->getNumArgs(); 219 } else { 220 numFormalParams = 0; 221 } 222 } else { 223 return; 224 } 225 226 // "nullPos" is the number of formal parameters at the end which 227 // effectively count as part of the variadic arguments. This is 228 // useful if you would prefer to not have *any* formal parameters, 229 // but the language forces you to have at least one. 230 unsigned nullPos = attr->getNullPos(); 231 assert((nullPos == 0 || nullPos == 1) && "invalid null position on sentinel"); 232 numFormalParams = (nullPos > numFormalParams ? 0 : numFormalParams - nullPos); 233 234 // The number of arguments which should follow the sentinel. 235 unsigned numArgsAfterSentinel = attr->getSentinel(); 236 237 // If there aren't enough arguments for all the formal parameters, 238 // the sentinel, and the args after the sentinel, complain. 239 if (numArgs < numFormalParams + numArgsAfterSentinel + 1) { 240 Diag(Loc, diag::warn_not_enough_argument) << D->getDeclName(); 241 Diag(D->getLocation(), diag::note_sentinel_here) << calleeType; 242 return; 243 } 244 245 // Otherwise, find the sentinel expression. 246 Expr *sentinelExpr = args[numArgs - numArgsAfterSentinel - 1]; 247 if (!sentinelExpr) return; 248 if (sentinelExpr->isValueDependent()) return; 249 250 // nullptr_t is always treated as null. 251 if (sentinelExpr->getType()->isNullPtrType()) return; 252 253 if (sentinelExpr->getType()->isAnyPointerType() && 254 sentinelExpr->IgnoreParenCasts()->isNullPointerConstant(Context, 255 Expr::NPC_ValueDependentIsNull)) 256 return; 257 258 // Unfortunately, __null has type 'int'. 259 if (isa<GNUNullExpr>(sentinelExpr)) return; 260 261 // Pick a reasonable string to insert. Optimistically use 'nil' or 262 // 'NULL' if those are actually defined in the context. Only use 263 // 'nil' for ObjC methods, where it's much more likely that the 264 // variadic arguments form a list of object pointers. 265 SourceLocation MissingNilLoc 266 = PP.getLocForEndOfToken(sentinelExpr->getLocEnd()); 267 std::string NullValue; 268 if (calleeType == CT_Method && 269 PP.getIdentifierInfo("nil")->hasMacroDefinition()) 270 NullValue = "nil"; 271 else if (PP.getIdentifierInfo("NULL")->hasMacroDefinition()) 272 NullValue = "NULL"; 273 else 274 NullValue = "(void*) 0"; 275 276 if (MissingNilLoc.isInvalid()) 277 Diag(Loc, diag::warn_missing_sentinel) << calleeType; 278 else 279 Diag(MissingNilLoc, diag::warn_missing_sentinel) 280 << calleeType 281 << FixItHint::CreateInsertion(MissingNilLoc, ", " + NullValue); 282 Diag(D->getLocation(), diag::note_sentinel_here) << calleeType; 283} 284 285SourceRange Sema::getExprRange(Expr *E) const { 286 return E ? E->getSourceRange() : SourceRange(); 287} 288 289//===----------------------------------------------------------------------===// 290// Standard Promotions and Conversions 291//===----------------------------------------------------------------------===// 292 293/// DefaultFunctionArrayConversion (C99 6.3.2.1p3, C99 6.3.2.1p4). 294ExprResult Sema::DefaultFunctionArrayConversion(Expr *E) { 295 // Handle any placeholder expressions which made it here. 296 if (E->getType()->isPlaceholderType()) { 297 ExprResult result = CheckPlaceholderExpr(E); 298 if (result.isInvalid()) return ExprError(); 299 E = result.take(); 300 } 301 302 QualType Ty = E->getType(); 303 assert(!Ty.isNull() && "DefaultFunctionArrayConversion - missing type"); 304 305 if (Ty->isFunctionType()) 306 E = ImpCastExprToType(E, Context.getPointerType(Ty), 307 CK_FunctionToPointerDecay).take(); 308 else if (Ty->isArrayType()) { 309 // In C90 mode, arrays only promote to pointers if the array expression is 310 // an lvalue. The relevant legalese is C90 6.2.2.1p3: "an lvalue that has 311 // type 'array of type' is converted to an expression that has type 'pointer 312 // to type'...". In C99 this was changed to: C99 6.3.2.1p3: "an expression 313 // that has type 'array of type' ...". The relevant change is "an lvalue" 314 // (C90) to "an expression" (C99). 315 // 316 // C++ 4.2p1: 317 // An lvalue or rvalue of type "array of N T" or "array of unknown bound of 318 // T" can be converted to an rvalue of type "pointer to T". 319 // 320 if (getLangOptions().C99 || getLangOptions().CPlusPlus || E->isLValue()) 321 E = ImpCastExprToType(E, Context.getArrayDecayedType(Ty), 322 CK_ArrayToPointerDecay).take(); 323 } 324 return Owned(E); 325} 326 327static void CheckForNullPointerDereference(Sema &S, Expr *E) { 328 // Check to see if we are dereferencing a null pointer. If so, 329 // and if not volatile-qualified, this is undefined behavior that the 330 // optimizer will delete, so warn about it. People sometimes try to use this 331 // to get a deterministic trap and are surprised by clang's behavior. This 332 // only handles the pattern "*null", which is a very syntactic check. 333 if (UnaryOperator *UO = dyn_cast<UnaryOperator>(E->IgnoreParenCasts())) 334 if (UO->getOpcode() == UO_Deref && 335 UO->getSubExpr()->IgnoreParenCasts()-> 336 isNullPointerConstant(S.Context, Expr::NPC_ValueDependentIsNotNull) && 337 !UO->getType().isVolatileQualified()) { 338 S.DiagRuntimeBehavior(UO->getOperatorLoc(), UO, 339 S.PDiag(diag::warn_indirection_through_null) 340 << UO->getSubExpr()->getSourceRange()); 341 S.DiagRuntimeBehavior(UO->getOperatorLoc(), UO, 342 S.PDiag(diag::note_indirection_through_null)); 343 } 344} 345 346ExprResult Sema::DefaultLvalueConversion(Expr *E) { 347 // Handle any placeholder expressions which made it here. 348 if (E->getType()->isPlaceholderType()) { 349 ExprResult result = CheckPlaceholderExpr(E); 350 if (result.isInvalid()) return ExprError(); 351 E = result.take(); 352 } 353 354 // C++ [conv.lval]p1: 355 // A glvalue of a non-function, non-array type T can be 356 // converted to a prvalue. 357 if (!E->isGLValue()) return Owned(E); 358 359 QualType T = E->getType(); 360 assert(!T.isNull() && "r-value conversion on typeless expression?"); 361 362 // We can't do lvalue-to-rvalue on atomics yet. 363 if (T->isAtomicType()) 364 return Owned(E); 365 366 // We don't want to throw lvalue-to-rvalue casts on top of 367 // expressions of certain types in C++. 368 if (getLangOptions().CPlusPlus && 369 (E->getType() == Context.OverloadTy || 370 T->isDependentType() || 371 T->isRecordType())) 372 return Owned(E); 373 374 // The C standard is actually really unclear on this point, and 375 // DR106 tells us what the result should be but not why. It's 376 // generally best to say that void types just doesn't undergo 377 // lvalue-to-rvalue at all. Note that expressions of unqualified 378 // 'void' type are never l-values, but qualified void can be. 379 if (T->isVoidType()) 380 return Owned(E); 381 382 CheckForNullPointerDereference(*this, E); 383 384 // C++ [conv.lval]p1: 385 // [...] If T is a non-class type, the type of the prvalue is the 386 // cv-unqualified version of T. Otherwise, the type of the 387 // rvalue is T. 388 // 389 // C99 6.3.2.1p2: 390 // If the lvalue has qualified type, the value has the unqualified 391 // version of the type of the lvalue; otherwise, the value has the 392 // type of the lvalue. 393 if (T.hasQualifiers()) 394 T = T.getUnqualifiedType(); 395 396 ExprResult Res = Owned(ImplicitCastExpr::Create(Context, T, CK_LValueToRValue, 397 E, 0, VK_RValue)); 398 399 return Res; 400} 401 402ExprResult Sema::DefaultFunctionArrayLvalueConversion(Expr *E) { 403 ExprResult Res = DefaultFunctionArrayConversion(E); 404 if (Res.isInvalid()) 405 return ExprError(); 406 Res = DefaultLvalueConversion(Res.take()); 407 if (Res.isInvalid()) 408 return ExprError(); 409 return move(Res); 410} 411 412 413/// UsualUnaryConversions - Performs various conversions that are common to most 414/// operators (C99 6.3). The conversions of array and function types are 415/// sometimes suppressed. For example, the array->pointer conversion doesn't 416/// apply if the array is an argument to the sizeof or address (&) operators. 417/// In these instances, this routine should *not* be called. 418ExprResult Sema::UsualUnaryConversions(Expr *E) { 419 // First, convert to an r-value. 420 ExprResult Res = DefaultFunctionArrayLvalueConversion(E); 421 if (Res.isInvalid()) 422 return Owned(E); 423 E = Res.take(); 424 425 QualType Ty = E->getType(); 426 assert(!Ty.isNull() && "UsualUnaryConversions - missing type"); 427 428 // Half FP is a bit different: it's a storage-only type, meaning that any 429 // "use" of it should be promoted to float. 430 if (Ty->isHalfType()) 431 return ImpCastExprToType(Res.take(), Context.FloatTy, CK_FloatingCast); 432 433 // Try to perform integral promotions if the object has a theoretically 434 // promotable type. 435 if (Ty->isIntegralOrUnscopedEnumerationType()) { 436 // C99 6.3.1.1p2: 437 // 438 // The following may be used in an expression wherever an int or 439 // unsigned int may be used: 440 // - an object or expression with an integer type whose integer 441 // conversion rank is less than or equal to the rank of int 442 // and unsigned int. 443 // - A bit-field of type _Bool, int, signed int, or unsigned int. 444 // 445 // If an int can represent all values of the original type, the 446 // value is converted to an int; otherwise, it is converted to an 447 // unsigned int. These are called the integer promotions. All 448 // other types are unchanged by the integer promotions. 449 450 QualType PTy = Context.isPromotableBitField(E); 451 if (!PTy.isNull()) { 452 E = ImpCastExprToType(E, PTy, CK_IntegralCast).take(); 453 return Owned(E); 454 } 455 if (Ty->isPromotableIntegerType()) { 456 QualType PT = Context.getPromotedIntegerType(Ty); 457 E = ImpCastExprToType(E, PT, CK_IntegralCast).take(); 458 return Owned(E); 459 } 460 } 461 return Owned(E); 462} 463 464/// DefaultArgumentPromotion (C99 6.5.2.2p6). Used for function calls that 465/// do not have a prototype. Arguments that have type float are promoted to 466/// double. All other argument types are converted by UsualUnaryConversions(). 467ExprResult Sema::DefaultArgumentPromotion(Expr *E) { 468 QualType Ty = E->getType(); 469 assert(!Ty.isNull() && "DefaultArgumentPromotion - missing type"); 470 471 ExprResult Res = UsualUnaryConversions(E); 472 if (Res.isInvalid()) 473 return Owned(E); 474 E = Res.take(); 475 476 // If this is a 'float' (CVR qualified or typedef) promote to double. 477 if (Ty->isSpecificBuiltinType(BuiltinType::Float)) 478 E = ImpCastExprToType(E, Context.DoubleTy, CK_FloatingCast).take(); 479 480 // C++ performs lvalue-to-rvalue conversion as a default argument 481 // promotion, even on class types, but note: 482 // C++11 [conv.lval]p2: 483 // When an lvalue-to-rvalue conversion occurs in an unevaluated 484 // operand or a subexpression thereof the value contained in the 485 // referenced object is not accessed. Otherwise, if the glvalue 486 // has a class type, the conversion copy-initializes a temporary 487 // of type T from the glvalue and the result of the conversion 488 // is a prvalue for the temporary. 489 // FIXME: add some way to gate this entire thing for correctness in 490 // potentially potentially evaluated contexts. 491 if (getLangOptions().CPlusPlus && E->isGLValue() && 492 ExprEvalContexts.back().Context != Unevaluated) { 493 ExprResult Temp = PerformCopyInitialization( 494 InitializedEntity::InitializeTemporary(E->getType()), 495 E->getExprLoc(), 496 Owned(E)); 497 if (Temp.isInvalid()) 498 return ExprError(); 499 E = Temp.get(); 500 } 501 502 return Owned(E); 503} 504 505/// DefaultVariadicArgumentPromotion - Like DefaultArgumentPromotion, but 506/// will warn if the resulting type is not a POD type, and rejects ObjC 507/// interfaces passed by value. 508ExprResult Sema::DefaultVariadicArgumentPromotion(Expr *E, VariadicCallType CT, 509 FunctionDecl *FDecl) { 510 if (const BuiltinType *PlaceholderTy = E->getType()->getAsPlaceholderType()) { 511 // Strip the unbridged-cast placeholder expression off, if applicable. 512 if (PlaceholderTy->getKind() == BuiltinType::ARCUnbridgedCast && 513 (CT == VariadicMethod || 514 (FDecl && FDecl->hasAttr<CFAuditedTransferAttr>()))) { 515 E = stripARCUnbridgedCast(E); 516 517 // Otherwise, do normal placeholder checking. 518 } else { 519 ExprResult ExprRes = CheckPlaceholderExpr(E); 520 if (ExprRes.isInvalid()) 521 return ExprError(); 522 E = ExprRes.take(); 523 } 524 } 525 526 ExprResult ExprRes = DefaultArgumentPromotion(E); 527 if (ExprRes.isInvalid()) 528 return ExprError(); 529 E = ExprRes.take(); 530 531 // Don't allow one to pass an Objective-C interface to a vararg. 532 if (E->getType()->isObjCObjectType() && 533 DiagRuntimeBehavior(E->getLocStart(), 0, 534 PDiag(diag::err_cannot_pass_objc_interface_to_vararg) 535 << E->getType() << CT)) 536 return ExprError(); 537 538 // Complain about passing non-POD types through varargs. However, don't 539 // perform this check for incomplete types, which we can get here when we're 540 // in an unevaluated context. 541 if (!E->getType()->isIncompleteType() && !E->getType().isPODType(Context)) { 542 // C++0x [expr.call]p7: 543 // Passing a potentially-evaluated argument of class type (Clause 9) 544 // having a non-trivial copy constructor, a non-trivial move constructor, 545 // or a non-trivial destructor, with no corresponding parameter, 546 // is conditionally-supported with implementation-defined semantics. 547 bool TrivialEnough = false; 548 if (getLangOptions().CPlusPlus0x && !E->getType()->isDependentType()) { 549 if (CXXRecordDecl *Record = E->getType()->getAsCXXRecordDecl()) { 550 if (Record->hasTrivialCopyConstructor() && 551 Record->hasTrivialMoveConstructor() && 552 Record->hasTrivialDestructor()) { 553 DiagRuntimeBehavior(E->getLocStart(), 0, 554 PDiag(diag::warn_cxx98_compat_pass_non_pod_arg_to_vararg) 555 << E->getType() << CT); 556 TrivialEnough = true; 557 } 558 } 559 } 560 561 if (!TrivialEnough && 562 getLangOptions().ObjCAutoRefCount && 563 E->getType()->isObjCLifetimeType()) 564 TrivialEnough = true; 565 566 if (TrivialEnough) { 567 // Nothing to diagnose. This is okay. 568 } else if (DiagRuntimeBehavior(E->getLocStart(), 0, 569 PDiag(diag::warn_cannot_pass_non_pod_arg_to_vararg) 570 << getLangOptions().CPlusPlus0x << E->getType() 571 << CT)) { 572 // Turn this into a trap. 573 CXXScopeSpec SS; 574 UnqualifiedId Name; 575 Name.setIdentifier(PP.getIdentifierInfo("__builtin_trap"), 576 E->getLocStart()); 577 ExprResult TrapFn = ActOnIdExpression(TUScope, SS, Name, true, false); 578 if (TrapFn.isInvalid()) 579 return ExprError(); 580 581 ExprResult Call = ActOnCallExpr(TUScope, TrapFn.get(), E->getLocStart(), 582 MultiExprArg(), E->getLocEnd()); 583 if (Call.isInvalid()) 584 return ExprError(); 585 586 ExprResult Comma = ActOnBinOp(TUScope, E->getLocStart(), tok::comma, 587 Call.get(), E); 588 if (Comma.isInvalid()) 589 return ExprError(); 590 E = Comma.get(); 591 } 592 } 593 594 return Owned(E); 595} 596 597/// \brief Converts an integer to complex float type. Helper function of 598/// UsualArithmeticConversions() 599/// 600/// \return false if the integer expression is an integer type and is 601/// successfully converted to the complex type. 602static bool handleIntegerToComplexFloatConversion(Sema &S, ExprResult &IntExpr, 603 ExprResult &ComplexExpr, 604 QualType IntTy, 605 QualType ComplexTy, 606 bool SkipCast) { 607 if (IntTy->isComplexType() || IntTy->isRealFloatingType()) return true; 608 if (SkipCast) return false; 609 if (IntTy->isIntegerType()) { 610 QualType fpTy = cast<ComplexType>(ComplexTy)->getElementType(); 611 IntExpr = S.ImpCastExprToType(IntExpr.take(), fpTy, CK_IntegralToFloating); 612 IntExpr = S.ImpCastExprToType(IntExpr.take(), ComplexTy, 613 CK_FloatingRealToComplex); 614 } else { 615 assert(IntTy->isComplexIntegerType()); 616 IntExpr = S.ImpCastExprToType(IntExpr.take(), ComplexTy, 617 CK_IntegralComplexToFloatingComplex); 618 } 619 return false; 620} 621 622/// \brief Takes two complex float types and converts them to the same type. 623/// Helper function of UsualArithmeticConversions() 624static QualType 625handleComplexFloatToComplexFloatConverstion(Sema &S, ExprResult &LHS, 626 ExprResult &RHS, QualType LHSType, 627 QualType RHSType, 628 bool IsCompAssign) { 629 int order = S.Context.getFloatingTypeOrder(LHSType, RHSType); 630 631 if (order < 0) { 632 // _Complex float -> _Complex double 633 if (!IsCompAssign) 634 LHS = S.ImpCastExprToType(LHS.take(), RHSType, CK_FloatingComplexCast); 635 return RHSType; 636 } 637 if (order > 0) 638 // _Complex float -> _Complex double 639 RHS = S.ImpCastExprToType(RHS.take(), LHSType, CK_FloatingComplexCast); 640 return LHSType; 641} 642 643/// \brief Converts otherExpr to complex float and promotes complexExpr if 644/// necessary. Helper function of UsualArithmeticConversions() 645static QualType handleOtherComplexFloatConversion(Sema &S, 646 ExprResult &ComplexExpr, 647 ExprResult &OtherExpr, 648 QualType ComplexTy, 649 QualType OtherTy, 650 bool ConvertComplexExpr, 651 bool ConvertOtherExpr) { 652 int order = S.Context.getFloatingTypeOrder(ComplexTy, OtherTy); 653 654 // If just the complexExpr is complex, the otherExpr needs to be converted, 655 // and the complexExpr might need to be promoted. 656 if (order > 0) { // complexExpr is wider 657 // float -> _Complex double 658 if (ConvertOtherExpr) { 659 QualType fp = cast<ComplexType>(ComplexTy)->getElementType(); 660 OtherExpr = S.ImpCastExprToType(OtherExpr.take(), fp, CK_FloatingCast); 661 OtherExpr = S.ImpCastExprToType(OtherExpr.take(), ComplexTy, 662 CK_FloatingRealToComplex); 663 } 664 return ComplexTy; 665 } 666 667 // otherTy is at least as wide. Find its corresponding complex type. 668 QualType result = (order == 0 ? ComplexTy : 669 S.Context.getComplexType(OtherTy)); 670 671 // double -> _Complex double 672 if (ConvertOtherExpr) 673 OtherExpr = S.ImpCastExprToType(OtherExpr.take(), result, 674 CK_FloatingRealToComplex); 675 676 // _Complex float -> _Complex double 677 if (ConvertComplexExpr && order < 0) 678 ComplexExpr = S.ImpCastExprToType(ComplexExpr.take(), result, 679 CK_FloatingComplexCast); 680 681 return result; 682} 683 684/// \brief Handle arithmetic conversion with complex types. Helper function of 685/// UsualArithmeticConversions() 686static QualType handleComplexFloatConversion(Sema &S, ExprResult &LHS, 687 ExprResult &RHS, QualType LHSType, 688 QualType RHSType, 689 bool IsCompAssign) { 690 // if we have an integer operand, the result is the complex type. 691 if (!handleIntegerToComplexFloatConversion(S, RHS, LHS, RHSType, LHSType, 692 /*skipCast*/false)) 693 return LHSType; 694 if (!handleIntegerToComplexFloatConversion(S, LHS, RHS, LHSType, RHSType, 695 /*skipCast*/IsCompAssign)) 696 return RHSType; 697 698 // This handles complex/complex, complex/float, or float/complex. 699 // When both operands are complex, the shorter operand is converted to the 700 // type of the longer, and that is the type of the result. This corresponds 701 // to what is done when combining two real floating-point operands. 702 // The fun begins when size promotion occur across type domains. 703 // From H&S 6.3.4: When one operand is complex and the other is a real 704 // floating-point type, the less precise type is converted, within it's 705 // real or complex domain, to the precision of the other type. For example, 706 // when combining a "long double" with a "double _Complex", the 707 // "double _Complex" is promoted to "long double _Complex". 708 709 bool LHSComplexFloat = LHSType->isComplexType(); 710 bool RHSComplexFloat = RHSType->isComplexType(); 711 712 // If both are complex, just cast to the more precise type. 713 if (LHSComplexFloat && RHSComplexFloat) 714 return handleComplexFloatToComplexFloatConverstion(S, LHS, RHS, 715 LHSType, RHSType, 716 IsCompAssign); 717 718 // If only one operand is complex, promote it if necessary and convert the 719 // other operand to complex. 720 if (LHSComplexFloat) 721 return handleOtherComplexFloatConversion( 722 S, LHS, RHS, LHSType, RHSType, /*convertComplexExpr*/!IsCompAssign, 723 /*convertOtherExpr*/ true); 724 725 assert(RHSComplexFloat); 726 return handleOtherComplexFloatConversion( 727 S, RHS, LHS, RHSType, LHSType, /*convertComplexExpr*/true, 728 /*convertOtherExpr*/ !IsCompAssign); 729} 730 731/// \brief Hande arithmetic conversion from integer to float. Helper function 732/// of UsualArithmeticConversions() 733static QualType handleIntToFloatConversion(Sema &S, ExprResult &FloatExpr, 734 ExprResult &IntExpr, 735 QualType FloatTy, QualType IntTy, 736 bool ConvertFloat, bool ConvertInt) { 737 if (IntTy->isIntegerType()) { 738 if (ConvertInt) 739 // Convert intExpr to the lhs floating point type. 740 IntExpr = S.ImpCastExprToType(IntExpr.take(), FloatTy, 741 CK_IntegralToFloating); 742 return FloatTy; 743 } 744 745 // Convert both sides to the appropriate complex float. 746 assert(IntTy->isComplexIntegerType()); 747 QualType result = S.Context.getComplexType(FloatTy); 748 749 // _Complex int -> _Complex float 750 if (ConvertInt) 751 IntExpr = S.ImpCastExprToType(IntExpr.take(), result, 752 CK_IntegralComplexToFloatingComplex); 753 754 // float -> _Complex float 755 if (ConvertFloat) 756 FloatExpr = S.ImpCastExprToType(FloatExpr.take(), result, 757 CK_FloatingRealToComplex); 758 759 return result; 760} 761 762/// \brief Handle arithmethic conversion with floating point types. Helper 763/// function of UsualArithmeticConversions() 764static QualType handleFloatConversion(Sema &S, ExprResult &LHS, 765 ExprResult &RHS, QualType LHSType, 766 QualType RHSType, bool IsCompAssign) { 767 bool LHSFloat = LHSType->isRealFloatingType(); 768 bool RHSFloat = RHSType->isRealFloatingType(); 769 770 // If we have two real floating types, convert the smaller operand 771 // to the bigger result. 772 if (LHSFloat && RHSFloat) { 773 int order = S.Context.getFloatingTypeOrder(LHSType, RHSType); 774 if (order > 0) { 775 RHS = S.ImpCastExprToType(RHS.take(), LHSType, CK_FloatingCast); 776 return LHSType; 777 } 778 779 assert(order < 0 && "illegal float comparison"); 780 if (!IsCompAssign) 781 LHS = S.ImpCastExprToType(LHS.take(), RHSType, CK_FloatingCast); 782 return RHSType; 783 } 784 785 if (LHSFloat) 786 return handleIntToFloatConversion(S, LHS, RHS, LHSType, RHSType, 787 /*convertFloat=*/!IsCompAssign, 788 /*convertInt=*/ true); 789 assert(RHSFloat); 790 return handleIntToFloatConversion(S, RHS, LHS, RHSType, LHSType, 791 /*convertInt=*/ true, 792 /*convertFloat=*/!IsCompAssign); 793} 794 795/// \brief Handle conversions with GCC complex int extension. Helper function 796/// of UsualArithmeticConversions() 797// FIXME: if the operands are (int, _Complex long), we currently 798// don't promote the complex. Also, signedness? 799static QualType handleComplexIntConversion(Sema &S, ExprResult &LHS, 800 ExprResult &RHS, QualType LHSType, 801 QualType RHSType, 802 bool IsCompAssign) { 803 const ComplexType *LHSComplexInt = LHSType->getAsComplexIntegerType(); 804 const ComplexType *RHSComplexInt = RHSType->getAsComplexIntegerType(); 805 806 if (LHSComplexInt && RHSComplexInt) { 807 int order = S.Context.getIntegerTypeOrder(LHSComplexInt->getElementType(), 808 RHSComplexInt->getElementType()); 809 assert(order && "inequal types with equal element ordering"); 810 if (order > 0) { 811 // _Complex int -> _Complex long 812 RHS = S.ImpCastExprToType(RHS.take(), LHSType, CK_IntegralComplexCast); 813 return LHSType; 814 } 815 816 if (!IsCompAssign) 817 LHS = S.ImpCastExprToType(LHS.take(), RHSType, CK_IntegralComplexCast); 818 return RHSType; 819 } 820 821 if (LHSComplexInt) { 822 // int -> _Complex int 823 // FIXME: This needs to take integer ranks into account 824 RHS = S.ImpCastExprToType(RHS.take(), LHSComplexInt->getElementType(), 825 CK_IntegralCast); 826 RHS = S.ImpCastExprToType(RHS.take(), LHSType, CK_IntegralRealToComplex); 827 return LHSType; 828 } 829 830 assert(RHSComplexInt); 831 // int -> _Complex int 832 // FIXME: This needs to take integer ranks into account 833 if (!IsCompAssign) { 834 LHS = S.ImpCastExprToType(LHS.take(), RHSComplexInt->getElementType(), 835 CK_IntegralCast); 836 LHS = S.ImpCastExprToType(LHS.take(), RHSType, CK_IntegralRealToComplex); 837 } 838 return RHSType; 839} 840 841/// \brief Handle integer arithmetic conversions. Helper function of 842/// UsualArithmeticConversions() 843static QualType handleIntegerConversion(Sema &S, ExprResult &LHS, 844 ExprResult &RHS, QualType LHSType, 845 QualType RHSType, bool IsCompAssign) { 846 // The rules for this case are in C99 6.3.1.8 847 int order = S.Context.getIntegerTypeOrder(LHSType, RHSType); 848 bool LHSSigned = LHSType->hasSignedIntegerRepresentation(); 849 bool RHSSigned = RHSType->hasSignedIntegerRepresentation(); 850 if (LHSSigned == RHSSigned) { 851 // Same signedness; use the higher-ranked type 852 if (order >= 0) { 853 RHS = S.ImpCastExprToType(RHS.take(), LHSType, CK_IntegralCast); 854 return LHSType; 855 } else if (!IsCompAssign) 856 LHS = S.ImpCastExprToType(LHS.take(), RHSType, CK_IntegralCast); 857 return RHSType; 858 } else if (order != (LHSSigned ? 1 : -1)) { 859 // The unsigned type has greater than or equal rank to the 860 // signed type, so use the unsigned type 861 if (RHSSigned) { 862 RHS = S.ImpCastExprToType(RHS.take(), LHSType, CK_IntegralCast); 863 return LHSType; 864 } else if (!IsCompAssign) 865 LHS = S.ImpCastExprToType(LHS.take(), RHSType, CK_IntegralCast); 866 return RHSType; 867 } else if (S.Context.getIntWidth(LHSType) != S.Context.getIntWidth(RHSType)) { 868 // The two types are different widths; if we are here, that 869 // means the signed type is larger than the unsigned type, so 870 // use the signed type. 871 if (LHSSigned) { 872 RHS = S.ImpCastExprToType(RHS.take(), LHSType, CK_IntegralCast); 873 return LHSType; 874 } else if (!IsCompAssign) 875 LHS = S.ImpCastExprToType(LHS.take(), RHSType, CK_IntegralCast); 876 return RHSType; 877 } else { 878 // The signed type is higher-ranked than the unsigned type, 879 // but isn't actually any bigger (like unsigned int and long 880 // on most 32-bit systems). Use the unsigned type corresponding 881 // to the signed type. 882 QualType result = 883 S.Context.getCorrespondingUnsignedType(LHSSigned ? LHSType : RHSType); 884 RHS = S.ImpCastExprToType(RHS.take(), result, CK_IntegralCast); 885 if (!IsCompAssign) 886 LHS = S.ImpCastExprToType(LHS.take(), result, CK_IntegralCast); 887 return result; 888 } 889} 890 891/// UsualArithmeticConversions - Performs various conversions that are common to 892/// binary operators (C99 6.3.1.8). If both operands aren't arithmetic, this 893/// routine returns the first non-arithmetic type found. The client is 894/// responsible for emitting appropriate error diagnostics. 895/// FIXME: verify the conversion rules for "complex int" are consistent with 896/// GCC. 897QualType Sema::UsualArithmeticConversions(ExprResult &LHS, ExprResult &RHS, 898 bool IsCompAssign) { 899 if (!IsCompAssign) { 900 LHS = UsualUnaryConversions(LHS.take()); 901 if (LHS.isInvalid()) 902 return QualType(); 903 } 904 905 RHS = UsualUnaryConversions(RHS.take()); 906 if (RHS.isInvalid()) 907 return QualType(); 908 909 // For conversion purposes, we ignore any qualifiers. 910 // For example, "const float" and "float" are equivalent. 911 QualType LHSType = 912 Context.getCanonicalType(LHS.get()->getType()).getUnqualifiedType(); 913 QualType RHSType = 914 Context.getCanonicalType(RHS.get()->getType()).getUnqualifiedType(); 915 916 // If both types are identical, no conversion is needed. 917 if (LHSType == RHSType) 918 return LHSType; 919 920 // If either side is a non-arithmetic type (e.g. a pointer), we are done. 921 // The caller can deal with this (e.g. pointer + int). 922 if (!LHSType->isArithmeticType() || !RHSType->isArithmeticType()) 923 return LHSType; 924 925 // Apply unary and bitfield promotions to the LHS's type. 926 QualType LHSUnpromotedType = LHSType; 927 if (LHSType->isPromotableIntegerType()) 928 LHSType = Context.getPromotedIntegerType(LHSType); 929 QualType LHSBitfieldPromoteTy = Context.isPromotableBitField(LHS.get()); 930 if (!LHSBitfieldPromoteTy.isNull()) 931 LHSType = LHSBitfieldPromoteTy; 932 if (LHSType != LHSUnpromotedType && !IsCompAssign) 933 LHS = ImpCastExprToType(LHS.take(), LHSType, CK_IntegralCast); 934 935 // If both types are identical, no conversion is needed. 936 if (LHSType == RHSType) 937 return LHSType; 938 939 // At this point, we have two different arithmetic types. 940 941 // Handle complex types first (C99 6.3.1.8p1). 942 if (LHSType->isComplexType() || RHSType->isComplexType()) 943 return handleComplexFloatConversion(*this, LHS, RHS, LHSType, RHSType, 944 IsCompAssign); 945 946 // Now handle "real" floating types (i.e. float, double, long double). 947 if (LHSType->isRealFloatingType() || RHSType->isRealFloatingType()) 948 return handleFloatConversion(*this, LHS, RHS, LHSType, RHSType, 949 IsCompAssign); 950 951 // Handle GCC complex int extension. 952 if (LHSType->isComplexIntegerType() || RHSType->isComplexIntegerType()) 953 return handleComplexIntConversion(*this, LHS, RHS, LHSType, RHSType, 954 IsCompAssign); 955 956 // Finally, we have two differing integer types. 957 return handleIntegerConversion(*this, LHS, RHS, LHSType, RHSType, 958 IsCompAssign); 959} 960 961//===----------------------------------------------------------------------===// 962// Semantic Analysis for various Expression Types 963//===----------------------------------------------------------------------===// 964 965 966ExprResult 967Sema::ActOnGenericSelectionExpr(SourceLocation KeyLoc, 968 SourceLocation DefaultLoc, 969 SourceLocation RParenLoc, 970 Expr *ControllingExpr, 971 MultiTypeArg ArgTypes, 972 MultiExprArg ArgExprs) { 973 unsigned NumAssocs = ArgTypes.size(); 974 assert(NumAssocs == ArgExprs.size()); 975 976 ParsedType *ParsedTypes = ArgTypes.release(); 977 Expr **Exprs = ArgExprs.release(); 978 979 TypeSourceInfo **Types = new TypeSourceInfo*[NumAssocs]; 980 for (unsigned i = 0; i < NumAssocs; ++i) { 981 if (ParsedTypes[i]) 982 (void) GetTypeFromParser(ParsedTypes[i], &Types[i]); 983 else 984 Types[i] = 0; 985 } 986 987 ExprResult ER = CreateGenericSelectionExpr(KeyLoc, DefaultLoc, RParenLoc, 988 ControllingExpr, Types, Exprs, 989 NumAssocs); 990 delete [] Types; 991 return ER; 992} 993 994ExprResult 995Sema::CreateGenericSelectionExpr(SourceLocation KeyLoc, 996 SourceLocation DefaultLoc, 997 SourceLocation RParenLoc, 998 Expr *ControllingExpr, 999 TypeSourceInfo **Types, 1000 Expr **Exprs, 1001 unsigned NumAssocs) { 1002 bool TypeErrorFound = false, 1003 IsResultDependent = ControllingExpr->isTypeDependent(), 1004 ContainsUnexpandedParameterPack 1005 = ControllingExpr->containsUnexpandedParameterPack(); 1006 1007 for (unsigned i = 0; i < NumAssocs; ++i) { 1008 if (Exprs[i]->containsUnexpandedParameterPack()) 1009 ContainsUnexpandedParameterPack = true; 1010 1011 if (Types[i]) { 1012 if (Types[i]->getType()->containsUnexpandedParameterPack()) 1013 ContainsUnexpandedParameterPack = true; 1014 1015 if (Types[i]->getType()->isDependentType()) { 1016 IsResultDependent = true; 1017 } else { 1018 // C1X 6.5.1.1p2 "The type name in a generic association shall specify a 1019 // complete object type other than a variably modified type." 1020 unsigned D = 0; 1021 if (Types[i]->getType()->isIncompleteType()) 1022 D = diag::err_assoc_type_incomplete; 1023 else if (!Types[i]->getType()->isObjectType()) 1024 D = diag::err_assoc_type_nonobject; 1025 else if (Types[i]->getType()->isVariablyModifiedType()) 1026 D = diag::err_assoc_type_variably_modified; 1027 1028 if (D != 0) { 1029 Diag(Types[i]->getTypeLoc().getBeginLoc(), D) 1030 << Types[i]->getTypeLoc().getSourceRange() 1031 << Types[i]->getType(); 1032 TypeErrorFound = true; 1033 } 1034 1035 // C1X 6.5.1.1p2 "No two generic associations in the same generic 1036 // selection shall specify compatible types." 1037 for (unsigned j = i+1; j < NumAssocs; ++j) 1038 if (Types[j] && !Types[j]->getType()->isDependentType() && 1039 Context.typesAreCompatible(Types[i]->getType(), 1040 Types[j]->getType())) { 1041 Diag(Types[j]->getTypeLoc().getBeginLoc(), 1042 diag::err_assoc_compatible_types) 1043 << Types[j]->getTypeLoc().getSourceRange() 1044 << Types[j]->getType() 1045 << Types[i]->getType(); 1046 Diag(Types[i]->getTypeLoc().getBeginLoc(), 1047 diag::note_compat_assoc) 1048 << Types[i]->getTypeLoc().getSourceRange() 1049 << Types[i]->getType(); 1050 TypeErrorFound = true; 1051 } 1052 } 1053 } 1054 } 1055 if (TypeErrorFound) 1056 return ExprError(); 1057 1058 // If we determined that the generic selection is result-dependent, don't 1059 // try to compute the result expression. 1060 if (IsResultDependent) 1061 return Owned(new (Context) GenericSelectionExpr( 1062 Context, KeyLoc, ControllingExpr, 1063 Types, Exprs, NumAssocs, DefaultLoc, 1064 RParenLoc, ContainsUnexpandedParameterPack)); 1065 1066 SmallVector<unsigned, 1> CompatIndices; 1067 unsigned DefaultIndex = -1U; 1068 for (unsigned i = 0; i < NumAssocs; ++i) { 1069 if (!Types[i]) 1070 DefaultIndex = i; 1071 else if (Context.typesAreCompatible(ControllingExpr->getType(), 1072 Types[i]->getType())) 1073 CompatIndices.push_back(i); 1074 } 1075 1076 // C1X 6.5.1.1p2 "The controlling expression of a generic selection shall have 1077 // type compatible with at most one of the types named in its generic 1078 // association list." 1079 if (CompatIndices.size() > 1) { 1080 // We strip parens here because the controlling expression is typically 1081 // parenthesized in macro definitions. 1082 ControllingExpr = ControllingExpr->IgnoreParens(); 1083 Diag(ControllingExpr->getLocStart(), diag::err_generic_sel_multi_match) 1084 << ControllingExpr->getSourceRange() << ControllingExpr->getType() 1085 << (unsigned) CompatIndices.size(); 1086 for (SmallVector<unsigned, 1>::iterator I = CompatIndices.begin(), 1087 E = CompatIndices.end(); I != E; ++I) { 1088 Diag(Types[*I]->getTypeLoc().getBeginLoc(), 1089 diag::note_compat_assoc) 1090 << Types[*I]->getTypeLoc().getSourceRange() 1091 << Types[*I]->getType(); 1092 } 1093 return ExprError(); 1094 } 1095 1096 // C1X 6.5.1.1p2 "If a generic selection has no default generic association, 1097 // its controlling expression shall have type compatible with exactly one of 1098 // the types named in its generic association list." 1099 if (DefaultIndex == -1U && CompatIndices.size() == 0) { 1100 // We strip parens here because the controlling expression is typically 1101 // parenthesized in macro definitions. 1102 ControllingExpr = ControllingExpr->IgnoreParens(); 1103 Diag(ControllingExpr->getLocStart(), diag::err_generic_sel_no_match) 1104 << ControllingExpr->getSourceRange() << ControllingExpr->getType(); 1105 return ExprError(); 1106 } 1107 1108 // C1X 6.5.1.1p3 "If a generic selection has a generic association with a 1109 // type name that is compatible with the type of the controlling expression, 1110 // then the result expression of the generic selection is the expression 1111 // in that generic association. Otherwise, the result expression of the 1112 // generic selection is the expression in the default generic association." 1113 unsigned ResultIndex = 1114 CompatIndices.size() ? CompatIndices[0] : DefaultIndex; 1115 1116 return Owned(new (Context) GenericSelectionExpr( 1117 Context, KeyLoc, ControllingExpr, 1118 Types, Exprs, NumAssocs, DefaultLoc, 1119 RParenLoc, ContainsUnexpandedParameterPack, 1120 ResultIndex)); 1121} 1122 1123/// ActOnStringLiteral - The specified tokens were lexed as pasted string 1124/// fragments (e.g. "foo" "bar" L"baz"). The result string has to handle string 1125/// concatenation ([C99 5.1.1.2, translation phase #6]), so it may come from 1126/// multiple tokens. However, the common case is that StringToks points to one 1127/// string. 1128/// 1129ExprResult 1130Sema::ActOnStringLiteral(const Token *StringToks, unsigned NumStringToks) { 1131 assert(NumStringToks && "Must have at least one string!"); 1132 1133 StringLiteralParser Literal(StringToks, NumStringToks, PP); 1134 if (Literal.hadError) 1135 return ExprError(); 1136 1137 SmallVector<SourceLocation, 4> StringTokLocs; 1138 for (unsigned i = 0; i != NumStringToks; ++i) 1139 StringTokLocs.push_back(StringToks[i].getLocation()); 1140 1141 QualType StrTy = Context.CharTy; 1142 if (Literal.isWide()) 1143 StrTy = Context.getWCharType(); 1144 else if (Literal.isUTF16()) 1145 StrTy = Context.Char16Ty; 1146 else if (Literal.isUTF32()) 1147 StrTy = Context.Char32Ty; 1148 else if (Literal.isPascal()) 1149 StrTy = Context.UnsignedCharTy; 1150 1151 StringLiteral::StringKind Kind = StringLiteral::Ascii; 1152 if (Literal.isWide()) 1153 Kind = StringLiteral::Wide; 1154 else if (Literal.isUTF8()) 1155 Kind = StringLiteral::UTF8; 1156 else if (Literal.isUTF16()) 1157 Kind = StringLiteral::UTF16; 1158 else if (Literal.isUTF32()) 1159 Kind = StringLiteral::UTF32; 1160 1161 // A C++ string literal has a const-qualified element type (C++ 2.13.4p1). 1162 if (getLangOptions().CPlusPlus || getLangOptions().ConstStrings) 1163 StrTy.addConst(); 1164 1165 // Get an array type for the string, according to C99 6.4.5. This includes 1166 // the nul terminator character as well as the string length for pascal 1167 // strings. 1168 StrTy = Context.getConstantArrayType(StrTy, 1169 llvm::APInt(32, Literal.GetNumStringChars()+1), 1170 ArrayType::Normal, 0); 1171 1172 // Pass &StringTokLocs[0], StringTokLocs.size() to factory! 1173 return Owned(StringLiteral::Create(Context, Literal.GetString(), 1174 Kind, Literal.Pascal, StrTy, 1175 &StringTokLocs[0], 1176 StringTokLocs.size())); 1177} 1178 1179enum CaptureResult { 1180 /// No capture is required. 1181 CR_NoCapture, 1182 1183 /// A capture is required. 1184 CR_Capture, 1185 1186 /// A by-ref capture is required. 1187 CR_CaptureByRef, 1188 1189 /// An error occurred when trying to capture the given variable. 1190 CR_Error 1191}; 1192 1193/// Diagnose an uncapturable value reference. 1194/// 1195/// \param var - the variable referenced 1196/// \param DC - the context which we couldn't capture through 1197static CaptureResult 1198diagnoseUncapturableValueReference(Sema &S, SourceLocation loc, 1199 VarDecl *var, DeclContext *DC) { 1200 switch (S.ExprEvalContexts.back().Context) { 1201 case Sema::Unevaluated: 1202 case Sema::ConstantEvaluated: 1203 // The argument will never be evaluated at runtime, so don't complain. 1204 return CR_NoCapture; 1205 1206 case Sema::PotentiallyEvaluated: 1207 case Sema::PotentiallyEvaluatedIfUsed: 1208 break; 1209 1210 case Sema::PotentiallyPotentiallyEvaluated: 1211 // FIXME: delay these! 1212 break; 1213 } 1214 1215 // Don't diagnose about capture if we're not actually in code right 1216 // now; in general, there are more appropriate places that will 1217 // diagnose this. 1218 if (!S.CurContext->isFunctionOrMethod()) return CR_NoCapture; 1219 1220 // Certain madnesses can happen with parameter declarations, which 1221 // we want to ignore. 1222 if (isa<ParmVarDecl>(var)) { 1223 // - If the parameter still belongs to the translation unit, then 1224 // we're actually just using one parameter in the declaration of 1225 // the next. This is useful in e.g. VLAs. 1226 if (isa<TranslationUnitDecl>(var->getDeclContext())) 1227 return CR_NoCapture; 1228 1229 // - This particular madness can happen in ill-formed default 1230 // arguments; claim it's okay and let downstream code handle it. 1231 if (S.CurContext == var->getDeclContext()->getParent()) 1232 return CR_NoCapture; 1233 } 1234 1235 DeclarationName functionName; 1236 if (FunctionDecl *fn = dyn_cast<FunctionDecl>(var->getDeclContext())) 1237 functionName = fn->getDeclName(); 1238 // FIXME: variable from enclosing block that we couldn't capture from! 1239 1240 S.Diag(loc, diag::err_reference_to_local_var_in_enclosing_function) 1241 << var->getIdentifier() << functionName; 1242 S.Diag(var->getLocation(), diag::note_local_variable_declared_here) 1243 << var->getIdentifier(); 1244 1245 return CR_Error; 1246} 1247 1248/// There is a well-formed capture at a particular scope level; 1249/// propagate it through all the nested blocks. 1250static CaptureResult propagateCapture(Sema &S, unsigned ValidScopeIndex, 1251 const BlockDecl::Capture &Capture) { 1252 VarDecl *var = Capture.getVariable(); 1253 1254 // Update all the inner blocks with the capture information. 1255 for (unsigned i = ValidScopeIndex + 1, e = S.FunctionScopes.size(); 1256 i != e; ++i) { 1257 BlockScopeInfo *innerBlock = cast<BlockScopeInfo>(S.FunctionScopes[i]); 1258 innerBlock->Captures.push_back( 1259 BlockDecl::Capture(Capture.getVariable(), Capture.isByRef(), 1260 /*nested*/ true, Capture.getCopyExpr())); 1261 innerBlock->CaptureMap[var] = innerBlock->Captures.size(); // +1 1262 } 1263 1264 return Capture.isByRef() ? CR_CaptureByRef : CR_Capture; 1265} 1266 1267/// shouldCaptureValueReference - Determine if a reference to the 1268/// given value in the current context requires a variable capture. 1269/// 1270/// This also keeps the captures set in the BlockScopeInfo records 1271/// up-to-date. 1272static CaptureResult shouldCaptureValueReference(Sema &S, SourceLocation loc, 1273 ValueDecl *Value) { 1274 // Only variables ever require capture. 1275 VarDecl *var = dyn_cast<VarDecl>(Value); 1276 if (!var) return CR_NoCapture; 1277 1278 // Fast path: variables from the current context never require capture. 1279 DeclContext *DC = S.CurContext; 1280 if (var->getDeclContext() == DC) return CR_NoCapture; 1281 1282 // Only variables with local storage require capture. 1283 // FIXME: What about 'const' variables in C++? 1284 if (!var->hasLocalStorage()) return CR_NoCapture; 1285 1286 // Otherwise, we need to capture. 1287 1288 unsigned functionScopesIndex = S.FunctionScopes.size() - 1; 1289 do { 1290 // Only blocks (and eventually C++0x closures) can capture; other 1291 // scopes don't work. 1292 if (!isa<BlockDecl>(DC)) 1293 return diagnoseUncapturableValueReference(S, loc, var, DC); 1294 1295 BlockScopeInfo *blockScope = 1296 cast<BlockScopeInfo>(S.FunctionScopes[functionScopesIndex]); 1297 assert(blockScope->TheDecl == static_cast<BlockDecl*>(DC)); 1298 1299 // Check whether we've already captured it in this block. If so, 1300 // we're done. 1301 if (unsigned indexPlus1 = blockScope->CaptureMap[var]) 1302 return propagateCapture(S, functionScopesIndex, 1303 blockScope->Captures[indexPlus1 - 1]); 1304 1305 functionScopesIndex--; 1306 DC = cast<BlockDecl>(DC)->getDeclContext(); 1307 } while (var->getDeclContext() != DC); 1308 1309 // Okay, we descended all the way to the block that defines the variable. 1310 // Actually try to capture it. 1311 QualType type = var->getType(); 1312 1313 // Prohibit variably-modified types. 1314 if (type->isVariablyModifiedType()) { 1315 S.Diag(loc, diag::err_ref_vm_type); 1316 S.Diag(var->getLocation(), diag::note_declared_at); 1317 return CR_Error; 1318 } 1319 1320 // Prohibit arrays, even in __block variables, but not references to 1321 // them. 1322 if (type->isArrayType()) { 1323 S.Diag(loc, diag::err_ref_array_type); 1324 S.Diag(var->getLocation(), diag::note_declared_at); 1325 return CR_Error; 1326 } 1327 1328 S.MarkDeclarationReferenced(loc, var); 1329 1330 // The BlocksAttr indicates the variable is bound by-reference. 1331 bool byRef = var->hasAttr<BlocksAttr>(); 1332 1333 // Build a copy expression. 1334 Expr *copyExpr = 0; 1335 const RecordType *rtype; 1336 if (!byRef && S.getLangOptions().CPlusPlus && !type->isDependentType() && 1337 (rtype = type->getAs<RecordType>())) { 1338 1339 // The capture logic needs the destructor, so make sure we mark it. 1340 // Usually this is unnecessary because most local variables have 1341 // their destructors marked at declaration time, but parameters are 1342 // an exception because it's technically only the call site that 1343 // actually requires the destructor. 1344 if (isa<ParmVarDecl>(var)) 1345 S.FinalizeVarWithDestructor(var, rtype); 1346 1347 // According to the blocks spec, the capture of a variable from 1348 // the stack requires a const copy constructor. This is not true 1349 // of the copy/move done to move a __block variable to the heap. 1350 type.addConst(); 1351 1352 Expr *declRef = new (S.Context) DeclRefExpr(var, type, VK_LValue, loc); 1353 ExprResult result = 1354 S.PerformCopyInitialization( 1355 InitializedEntity::InitializeBlock(var->getLocation(), 1356 type, false), 1357 loc, S.Owned(declRef)); 1358 1359 // Build a full-expression copy expression if initialization 1360 // succeeded and used a non-trivial constructor. Recover from 1361 // errors by pretending that the copy isn't necessary. 1362 if (!result.isInvalid() && 1363 !cast<CXXConstructExpr>(result.get())->getConstructor()->isTrivial()) { 1364 result = S.MaybeCreateExprWithCleanups(result); 1365 copyExpr = result.take(); 1366 } 1367 } 1368 1369 // We're currently at the declarer; go back to the closure. 1370 functionScopesIndex++; 1371 BlockScopeInfo *blockScope = 1372 cast<BlockScopeInfo>(S.FunctionScopes[functionScopesIndex]); 1373 1374 // Build a valid capture in this scope. 1375 blockScope->Captures.push_back( 1376 BlockDecl::Capture(var, byRef, /*nested*/ false, copyExpr)); 1377 blockScope->CaptureMap[var] = blockScope->Captures.size(); // +1 1378 1379 // Propagate that to inner captures if necessary. 1380 return propagateCapture(S, functionScopesIndex, 1381 blockScope->Captures.back()); 1382} 1383 1384static ExprResult BuildBlockDeclRefExpr(Sema &S, ValueDecl *VD, 1385 const DeclarationNameInfo &NameInfo, 1386 bool ByRef) { 1387 assert(isa<VarDecl>(VD) && "capturing non-variable"); 1388 1389 VarDecl *var = cast<VarDecl>(VD); 1390 assert(var->hasLocalStorage() && "capturing non-local"); 1391 assert(ByRef == var->hasAttr<BlocksAttr>() && "byref set wrong"); 1392 1393 QualType exprType = var->getType().getNonReferenceType(); 1394 1395 BlockDeclRefExpr *BDRE; 1396 if (!ByRef) { 1397 // The variable will be bound by copy; make it const within the 1398 // closure, but record that this was done in the expression. 1399 bool constAdded = !exprType.isConstQualified(); 1400 exprType.addConst(); 1401 1402 BDRE = new (S.Context) BlockDeclRefExpr(var, exprType, VK_LValue, 1403 NameInfo.getLoc(), false, 1404 constAdded); 1405 } else { 1406 BDRE = new (S.Context) BlockDeclRefExpr(var, exprType, VK_LValue, 1407 NameInfo.getLoc(), true); 1408 } 1409 1410 return S.Owned(BDRE); 1411} 1412 1413ExprResult 1414Sema::BuildDeclRefExpr(ValueDecl *D, QualType Ty, ExprValueKind VK, 1415 SourceLocation Loc, 1416 const CXXScopeSpec *SS) { 1417 DeclarationNameInfo NameInfo(D->getDeclName(), Loc); 1418 return BuildDeclRefExpr(D, Ty, VK, NameInfo, SS); 1419} 1420 1421/// BuildDeclRefExpr - Build an expression that references a 1422/// declaration that does not require a closure capture. 1423ExprResult 1424Sema::BuildDeclRefExpr(ValueDecl *D, QualType Ty, ExprValueKind VK, 1425 const DeclarationNameInfo &NameInfo, 1426 const CXXScopeSpec *SS) { 1427 if (getLangOptions().CUDA) 1428 if (const FunctionDecl *Caller = dyn_cast<FunctionDecl>(CurContext)) 1429 if (const FunctionDecl *Callee = dyn_cast<FunctionDecl>(D)) { 1430 CUDAFunctionTarget CallerTarget = IdentifyCUDATarget(Caller), 1431 CalleeTarget = IdentifyCUDATarget(Callee); 1432 if (CheckCUDATarget(CallerTarget, CalleeTarget)) { 1433 Diag(NameInfo.getLoc(), diag::err_ref_bad_target) 1434 << CalleeTarget << D->getIdentifier() << CallerTarget; 1435 Diag(D->getLocation(), diag::note_previous_decl) 1436 << D->getIdentifier(); 1437 return ExprError(); 1438 } 1439 } 1440 1441 MarkDeclarationReferenced(NameInfo.getLoc(), D); 1442 1443 Expr *E = DeclRefExpr::Create(Context, 1444 SS? SS->getWithLocInContext(Context) 1445 : NestedNameSpecifierLoc(), 1446 D, NameInfo, Ty, VK); 1447 1448 // Just in case we're building an illegal pointer-to-member. 1449 FieldDecl *FD = dyn_cast<FieldDecl>(D); 1450 if (FD && FD->isBitField()) 1451 E->setObjectKind(OK_BitField); 1452 1453 return Owned(E); 1454} 1455 1456/// Decomposes the given name into a DeclarationNameInfo, its location, and 1457/// possibly a list of template arguments. 1458/// 1459/// If this produces template arguments, it is permitted to call 1460/// DecomposeTemplateName. 1461/// 1462/// This actually loses a lot of source location information for 1463/// non-standard name kinds; we should consider preserving that in 1464/// some way. 1465void 1466Sema::DecomposeUnqualifiedId(const UnqualifiedId &Id, 1467 TemplateArgumentListInfo &Buffer, 1468 DeclarationNameInfo &NameInfo, 1469 const TemplateArgumentListInfo *&TemplateArgs) { 1470 if (Id.getKind() == UnqualifiedId::IK_TemplateId) { 1471 Buffer.setLAngleLoc(Id.TemplateId->LAngleLoc); 1472 Buffer.setRAngleLoc(Id.TemplateId->RAngleLoc); 1473 1474 ASTTemplateArgsPtr TemplateArgsPtr(*this, 1475 Id.TemplateId->getTemplateArgs(), 1476 Id.TemplateId->NumArgs); 1477 translateTemplateArguments(TemplateArgsPtr, Buffer); 1478 TemplateArgsPtr.release(); 1479 1480 TemplateName TName = Id.TemplateId->Template.get(); 1481 SourceLocation TNameLoc = Id.TemplateId->TemplateNameLoc; 1482 NameInfo = Context.getNameForTemplate(TName, TNameLoc); 1483 TemplateArgs = &Buffer; 1484 } else { 1485 NameInfo = GetNameFromUnqualifiedId(Id); 1486 TemplateArgs = 0; 1487 } 1488} 1489 1490/// Diagnose an empty lookup. 1491/// 1492/// \return false if new lookup candidates were found 1493bool Sema::DiagnoseEmptyLookup(Scope *S, CXXScopeSpec &SS, LookupResult &R, 1494 CorrectTypoContext CTC, 1495 TemplateArgumentListInfo *ExplicitTemplateArgs, 1496 Expr **Args, unsigned NumArgs) { 1497 DeclarationName Name = R.getLookupName(); 1498 1499 unsigned diagnostic = diag::err_undeclared_var_use; 1500 unsigned diagnostic_suggest = diag::err_undeclared_var_use_suggest; 1501 if (Name.getNameKind() == DeclarationName::CXXOperatorName || 1502 Name.getNameKind() == DeclarationName::CXXLiteralOperatorName || 1503 Name.getNameKind() == DeclarationName::CXXConversionFunctionName) { 1504 diagnostic = diag::err_undeclared_use; 1505 diagnostic_suggest = diag::err_undeclared_use_suggest; 1506 } 1507 1508 // If the original lookup was an unqualified lookup, fake an 1509 // unqualified lookup. This is useful when (for example) the 1510 // original lookup would not have found something because it was a 1511 // dependent name. 1512 DeclContext *DC = SS.isEmpty() ? CurContext : 0; 1513 while (DC) { 1514 if (isa<CXXRecordDecl>(DC)) { 1515 LookupQualifiedName(R, DC); 1516 1517 if (!R.empty()) { 1518 // Don't give errors about ambiguities in this lookup. 1519 R.suppressDiagnostics(); 1520 1521 // During a default argument instantiation the CurContext points 1522 // to a CXXMethodDecl; but we can't apply a this-> fixit inside a 1523 // function parameter list, hence add an explicit check. 1524 bool isDefaultArgument = !ActiveTemplateInstantiations.empty() && 1525 ActiveTemplateInstantiations.back().Kind == 1526 ActiveTemplateInstantiation::DefaultFunctionArgumentInstantiation; 1527 CXXMethodDecl *CurMethod = dyn_cast<CXXMethodDecl>(CurContext); 1528 bool isInstance = CurMethod && 1529 CurMethod->isInstance() && 1530 DC == CurMethod->getParent() && !isDefaultArgument; 1531 1532 1533 // Give a code modification hint to insert 'this->'. 1534 // TODO: fixit for inserting 'Base<T>::' in the other cases. 1535 // Actually quite difficult! 1536 if (isInstance) { 1537 UnresolvedLookupExpr *ULE = cast<UnresolvedLookupExpr>( 1538 CallsUndergoingInstantiation.back()->getCallee()); 1539 CXXMethodDecl *DepMethod = cast_or_null<CXXMethodDecl>( 1540 CurMethod->getInstantiatedFromMemberFunction()); 1541 if (DepMethod) { 1542 if (getLangOptions().MicrosoftMode) 1543 diagnostic = diag::warn_found_via_dependent_bases_lookup; 1544 Diag(R.getNameLoc(), diagnostic) << Name 1545 << FixItHint::CreateInsertion(R.getNameLoc(), "this->"); 1546 QualType DepThisType = DepMethod->getThisType(Context); 1547 CXXThisExpr *DepThis = new (Context) CXXThisExpr( 1548 R.getNameLoc(), DepThisType, false); 1549 TemplateArgumentListInfo TList; 1550 if (ULE->hasExplicitTemplateArgs()) 1551 ULE->copyTemplateArgumentsInto(TList); 1552 1553 CXXScopeSpec SS; 1554 SS.Adopt(ULE->getQualifierLoc()); 1555 CXXDependentScopeMemberExpr *DepExpr = 1556 CXXDependentScopeMemberExpr::Create( 1557 Context, DepThis, DepThisType, true, SourceLocation(), 1558 SS.getWithLocInContext(Context), NULL, 1559 R.getLookupNameInfo(), 1560 ULE->hasExplicitTemplateArgs() ? &TList : 0); 1561 CallsUndergoingInstantiation.back()->setCallee(DepExpr); 1562 } else { 1563 // FIXME: we should be able to handle this case too. It is correct 1564 // to add this-> here. This is a workaround for PR7947. 1565 Diag(R.getNameLoc(), diagnostic) << Name; 1566 } 1567 } else { 1568 if (getLangOptions().MicrosoftMode) 1569 diagnostic = diag::warn_found_via_dependent_bases_lookup; 1570 Diag(R.getNameLoc(), diagnostic) << Name; 1571 } 1572 1573 // Do we really want to note all of these? 1574 for (LookupResult::iterator I = R.begin(), E = R.end(); I != E; ++I) 1575 Diag((*I)->getLocation(), diag::note_dependent_var_use); 1576 1577 // Return true if we are inside a default argument instantiation 1578 // and the found name refers to an instance member function, otherwise 1579 // the function calling DiagnoseEmptyLookup will try to create an 1580 // implicit member call and this is wrong for default argument. 1581 if (isDefaultArgument && ((*R.begin())->isCXXInstanceMember())) { 1582 Diag(R.getNameLoc(), diag::err_member_call_without_object); 1583 return true; 1584 } 1585 1586 // Tell the callee to try to recover. 1587 return false; 1588 } 1589 1590 R.clear(); 1591 } 1592 1593 // In Microsoft mode, if we are performing lookup from within a friend 1594 // function definition declared at class scope then we must set 1595 // DC to the lexical parent to be able to search into the parent 1596 // class. 1597 if (getLangOptions().MicrosoftMode && isa<FunctionDecl>(DC) && 1598 cast<FunctionDecl>(DC)->getFriendObjectKind() && 1599 DC->getLexicalParent()->isRecord()) 1600 DC = DC->getLexicalParent(); 1601 else 1602 DC = DC->getParent(); 1603 } 1604 1605 // We didn't find anything, so try to correct for a typo. 1606 TypoCorrection Corrected; 1607 if (S && (Corrected = CorrectTypo(R.getLookupNameInfo(), R.getLookupKind(), 1608 S, &SS, NULL, false, CTC))) { 1609 std::string CorrectedStr(Corrected.getAsString(getLangOptions())); 1610 std::string CorrectedQuotedStr(Corrected.getQuoted(getLangOptions())); 1611 R.setLookupName(Corrected.getCorrection()); 1612 1613 if (NamedDecl *ND = Corrected.getCorrectionDecl()) { 1614 if (Corrected.isOverloaded()) { 1615 OverloadCandidateSet OCS(R.getNameLoc()); 1616 OverloadCandidateSet::iterator Best; 1617 for (TypoCorrection::decl_iterator CD = Corrected.begin(), 1618 CDEnd = Corrected.end(); 1619 CD != CDEnd; ++CD) { 1620 if (FunctionTemplateDecl *FTD = 1621 dyn_cast<FunctionTemplateDecl>(*CD)) 1622 AddTemplateOverloadCandidate( 1623 FTD, DeclAccessPair::make(FTD, AS_none), ExplicitTemplateArgs, 1624 Args, NumArgs, OCS); 1625 else if (FunctionDecl *FD = dyn_cast<FunctionDecl>(*CD)) 1626 if (!ExplicitTemplateArgs || ExplicitTemplateArgs->size() == 0) 1627 AddOverloadCandidate(FD, DeclAccessPair::make(FD, AS_none), 1628 Args, NumArgs, OCS); 1629 } 1630 switch (OCS.BestViableFunction(*this, R.getNameLoc(), Best)) { 1631 case OR_Success: 1632 ND = Best->Function; 1633 break; 1634 default: 1635 break; 1636 } 1637 } 1638 R.addDecl(ND); 1639 if (isa<ValueDecl>(ND) || isa<FunctionTemplateDecl>(ND)) { 1640 if (SS.isEmpty()) 1641 Diag(R.getNameLoc(), diagnostic_suggest) << Name << CorrectedQuotedStr 1642 << FixItHint::CreateReplacement(R.getNameLoc(), CorrectedStr); 1643 else 1644 Diag(R.getNameLoc(), diag::err_no_member_suggest) 1645 << Name << computeDeclContext(SS, false) << CorrectedQuotedStr 1646 << SS.getRange() 1647 << FixItHint::CreateReplacement(R.getNameLoc(), CorrectedStr); 1648 if (ND) 1649 Diag(ND->getLocation(), diag::note_previous_decl) 1650 << CorrectedQuotedStr; 1651 1652 // Tell the callee to try to recover. 1653 return false; 1654 } 1655 1656 if (isa<TypeDecl>(ND) || isa<ObjCInterfaceDecl>(ND)) { 1657 // FIXME: If we ended up with a typo for a type name or 1658 // Objective-C class name, we're in trouble because the parser 1659 // is in the wrong place to recover. Suggest the typo 1660 // correction, but don't make it a fix-it since we're not going 1661 // to recover well anyway. 1662 if (SS.isEmpty()) 1663 Diag(R.getNameLoc(), diagnostic_suggest) 1664 << Name << CorrectedQuotedStr; 1665 else 1666 Diag(R.getNameLoc(), diag::err_no_member_suggest) 1667 << Name << computeDeclContext(SS, false) << CorrectedQuotedStr 1668 << SS.getRange(); 1669 1670 // Don't try to recover; it won't work. 1671 return true; 1672 } 1673 } else { 1674 // FIXME: We found a keyword. Suggest it, but don't provide a fix-it 1675 // because we aren't able to recover. 1676 if (SS.isEmpty()) 1677 Diag(R.getNameLoc(), diagnostic_suggest) << Name << CorrectedQuotedStr; 1678 else 1679 Diag(R.getNameLoc(), diag::err_no_member_suggest) 1680 << Name << computeDeclContext(SS, false) << CorrectedQuotedStr 1681 << SS.getRange(); 1682 return true; 1683 } 1684 } 1685 R.clear(); 1686 1687 // Emit a special diagnostic for failed member lookups. 1688 // FIXME: computing the declaration context might fail here (?) 1689 if (!SS.isEmpty()) { 1690 Diag(R.getNameLoc(), diag::err_no_member) 1691 << Name << computeDeclContext(SS, false) 1692 << SS.getRange(); 1693 return true; 1694 } 1695 1696 // Give up, we can't recover. 1697 Diag(R.getNameLoc(), diagnostic) << Name; 1698 return true; 1699} 1700 1701ExprResult Sema::ActOnIdExpression(Scope *S, 1702 CXXScopeSpec &SS, 1703 UnqualifiedId &Id, 1704 bool HasTrailingLParen, 1705 bool IsAddressOfOperand) { 1706 assert(!(IsAddressOfOperand && HasTrailingLParen) && 1707 "cannot be direct & operand and have a trailing lparen"); 1708 1709 if (SS.isInvalid()) 1710 return ExprError(); 1711 1712 TemplateArgumentListInfo TemplateArgsBuffer; 1713 1714 // Decompose the UnqualifiedId into the following data. 1715 DeclarationNameInfo NameInfo; 1716 const TemplateArgumentListInfo *TemplateArgs; 1717 DecomposeUnqualifiedId(Id, TemplateArgsBuffer, NameInfo, TemplateArgs); 1718 1719 DeclarationName Name = NameInfo.getName(); 1720 IdentifierInfo *II = Name.getAsIdentifierInfo(); 1721 SourceLocation NameLoc = NameInfo.getLoc(); 1722 1723 // C++ [temp.dep.expr]p3: 1724 // An id-expression is type-dependent if it contains: 1725 // -- an identifier that was declared with a dependent type, 1726 // (note: handled after lookup) 1727 // -- a template-id that is dependent, 1728 // (note: handled in BuildTemplateIdExpr) 1729 // -- a conversion-function-id that specifies a dependent type, 1730 // -- a nested-name-specifier that contains a class-name that 1731 // names a dependent type. 1732 // Determine whether this is a member of an unknown specialization; 1733 // we need to handle these differently. 1734 bool DependentID = false; 1735 if (Name.getNameKind() == DeclarationName::CXXConversionFunctionName && 1736 Name.getCXXNameType()->isDependentType()) { 1737 DependentID = true; 1738 } else if (SS.isSet()) { 1739 if (DeclContext *DC = computeDeclContext(SS, false)) { 1740 if (RequireCompleteDeclContext(SS, DC)) 1741 return ExprError(); 1742 } else { 1743 DependentID = true; 1744 } 1745 } 1746 1747 if (DependentID) 1748 return ActOnDependentIdExpression(SS, NameInfo, IsAddressOfOperand, 1749 TemplateArgs); 1750 1751 bool IvarLookupFollowUp = false; 1752 // Perform the required lookup. 1753 LookupResult R(*this, NameInfo, 1754 (Id.getKind() == UnqualifiedId::IK_ImplicitSelfParam) 1755 ? LookupObjCImplicitSelfParam : LookupOrdinaryName); 1756 if (TemplateArgs) { 1757 // Lookup the template name again to correctly establish the context in 1758 // which it was found. This is really unfortunate as we already did the 1759 // lookup to determine that it was a template name in the first place. If 1760 // this becomes a performance hit, we can work harder to preserve those 1761 // results until we get here but it's likely not worth it. 1762 bool MemberOfUnknownSpecialization; 1763 LookupTemplateName(R, S, SS, QualType(), /*EnteringContext=*/false, 1764 MemberOfUnknownSpecialization); 1765 1766 if (MemberOfUnknownSpecialization || 1767 (R.getResultKind() == LookupResult::NotFoundInCurrentInstantiation)) 1768 return ActOnDependentIdExpression(SS, NameInfo, IsAddressOfOperand, 1769 TemplateArgs); 1770 } else { 1771 IvarLookupFollowUp = (!SS.isSet() && II && getCurMethodDecl()); 1772 LookupParsedName(R, S, &SS, !IvarLookupFollowUp); 1773 1774 // If the result might be in a dependent base class, this is a dependent 1775 // id-expression. 1776 if (R.getResultKind() == LookupResult::NotFoundInCurrentInstantiation) 1777 return ActOnDependentIdExpression(SS, NameInfo, IsAddressOfOperand, 1778 TemplateArgs); 1779 1780 // If this reference is in an Objective-C method, then we need to do 1781 // some special Objective-C lookup, too. 1782 if (IvarLookupFollowUp) { 1783 ExprResult E(LookupInObjCMethod(R, S, II, true)); 1784 if (E.isInvalid()) 1785 return ExprError(); 1786 1787 if (Expr *Ex = E.takeAs<Expr>()) 1788 return Owned(Ex); 1789 1790 // for further use, this must be set to false if in class method. 1791 IvarLookupFollowUp = getCurMethodDecl()->isInstanceMethod(); 1792 } 1793 } 1794 1795 if (R.isAmbiguous()) 1796 return ExprError(); 1797 1798 // Determine whether this name might be a candidate for 1799 // argument-dependent lookup. 1800 bool ADL = UseArgumentDependentLookup(SS, R, HasTrailingLParen); 1801 1802 if (R.empty() && !ADL) { 1803 // Otherwise, this could be an implicitly declared function reference (legal 1804 // in C90, extension in C99, forbidden in C++). 1805 if (HasTrailingLParen && II && !getLangOptions().CPlusPlus) { 1806 NamedDecl *D = ImplicitlyDefineFunction(NameLoc, *II, S); 1807 if (D) R.addDecl(D); 1808 } 1809 1810 // If this name wasn't predeclared and if this is not a function 1811 // call, diagnose the problem. 1812 if (R.empty()) { 1813 1814 // In Microsoft mode, if we are inside a template class member function 1815 // and we can't resolve an identifier then assume the identifier is type 1816 // dependent. The goal is to postpone name lookup to instantiation time 1817 // to be able to search into type dependent base classes. 1818 if (getLangOptions().MicrosoftMode && CurContext->isDependentContext() && 1819 isa<CXXMethodDecl>(CurContext)) 1820 return ActOnDependentIdExpression(SS, NameInfo, IsAddressOfOperand, 1821 TemplateArgs); 1822 1823 if (DiagnoseEmptyLookup(S, SS, R, CTC_Unknown)) 1824 return ExprError(); 1825 1826 assert(!R.empty() && 1827 "DiagnoseEmptyLookup returned false but added no results"); 1828 1829 // If we found an Objective-C instance variable, let 1830 // LookupInObjCMethod build the appropriate expression to 1831 // reference the ivar. 1832 if (ObjCIvarDecl *Ivar = R.getAsSingle<ObjCIvarDecl>()) { 1833 R.clear(); 1834 ExprResult E(LookupInObjCMethod(R, S, Ivar->getIdentifier())); 1835 // In a hopelessly buggy code, Objective-C instance variable 1836 // lookup fails and no expression will be built to reference it. 1837 if (!E.isInvalid() && !E.get()) 1838 return ExprError(); 1839 return move(E); 1840 } 1841 } 1842 } 1843 1844 // This is guaranteed from this point on. 1845 assert(!R.empty() || ADL); 1846 1847 // Check whether this might be a C++ implicit instance member access. 1848 // C++ [class.mfct.non-static]p3: 1849 // When an id-expression that is not part of a class member access 1850 // syntax and not used to form a pointer to member is used in the 1851 // body of a non-static member function of class X, if name lookup 1852 // resolves the name in the id-expression to a non-static non-type 1853 // member of some class C, the id-expression is transformed into a 1854 // class member access expression using (*this) as the 1855 // postfix-expression to the left of the . operator. 1856 // 1857 // But we don't actually need to do this for '&' operands if R 1858 // resolved to a function or overloaded function set, because the 1859 // expression is ill-formed if it actually works out to be a 1860 // non-static member function: 1861 // 1862 // C++ [expr.ref]p4: 1863 // Otherwise, if E1.E2 refers to a non-static member function. . . 1864 // [t]he expression can be used only as the left-hand operand of a 1865 // member function call. 1866 // 1867 // There are other safeguards against such uses, but it's important 1868 // to get this right here so that we don't end up making a 1869 // spuriously dependent expression if we're inside a dependent 1870 // instance method. 1871 if (!R.empty() && (*R.begin())->isCXXClassMember()) { 1872 bool MightBeImplicitMember; 1873 if (!IsAddressOfOperand) 1874 MightBeImplicitMember = true; 1875 else if (!SS.isEmpty()) 1876 MightBeImplicitMember = false; 1877 else if (R.isOverloadedResult()) 1878 MightBeImplicitMember = false; 1879 else if (R.isUnresolvableResult()) 1880 MightBeImplicitMember = true; 1881 else 1882 MightBeImplicitMember = isa<FieldDecl>(R.getFoundDecl()) || 1883 isa<IndirectFieldDecl>(R.getFoundDecl()); 1884 1885 if (MightBeImplicitMember) 1886 return BuildPossibleImplicitMemberExpr(SS, R, TemplateArgs); 1887 } 1888 1889 if (TemplateArgs) 1890 return BuildTemplateIdExpr(SS, R, ADL, *TemplateArgs); 1891 1892 return BuildDeclarationNameExpr(SS, R, ADL); 1893} 1894 1895/// BuildQualifiedDeclarationNameExpr - Build a C++ qualified 1896/// declaration name, generally during template instantiation. 1897/// There's a large number of things which don't need to be done along 1898/// this path. 1899ExprResult 1900Sema::BuildQualifiedDeclarationNameExpr(CXXScopeSpec &SS, 1901 const DeclarationNameInfo &NameInfo) { 1902 DeclContext *DC; 1903 if (!(DC = computeDeclContext(SS, false)) || DC->isDependentContext()) 1904 return BuildDependentDeclRefExpr(SS, NameInfo, 0); 1905 1906 if (RequireCompleteDeclContext(SS, DC)) 1907 return ExprError(); 1908 1909 LookupResult R(*this, NameInfo, LookupOrdinaryName); 1910 LookupQualifiedName(R, DC); 1911 1912 if (R.isAmbiguous()) 1913 return ExprError(); 1914 1915 if (R.empty()) { 1916 Diag(NameInfo.getLoc(), diag::err_no_member) 1917 << NameInfo.getName() << DC << SS.getRange(); 1918 return ExprError(); 1919 } 1920 1921 return BuildDeclarationNameExpr(SS, R, /*ADL*/ false); 1922} 1923 1924/// LookupInObjCMethod - The parser has read a name in, and Sema has 1925/// detected that we're currently inside an ObjC method. Perform some 1926/// additional lookup. 1927/// 1928/// Ideally, most of this would be done by lookup, but there's 1929/// actually quite a lot of extra work involved. 1930/// 1931/// Returns a null sentinel to indicate trivial success. 1932ExprResult 1933Sema::LookupInObjCMethod(LookupResult &Lookup, Scope *S, 1934 IdentifierInfo *II, bool AllowBuiltinCreation) { 1935 SourceLocation Loc = Lookup.getNameLoc(); 1936 ObjCMethodDecl *CurMethod = getCurMethodDecl(); 1937 1938 // There are two cases to handle here. 1) scoped lookup could have failed, 1939 // in which case we should look for an ivar. 2) scoped lookup could have 1940 // found a decl, but that decl is outside the current instance method (i.e. 1941 // a global variable). In these two cases, we do a lookup for an ivar with 1942 // this name, if the lookup sucedes, we replace it our current decl. 1943 1944 // If we're in a class method, we don't normally want to look for 1945 // ivars. But if we don't find anything else, and there's an 1946 // ivar, that's an error. 1947 bool IsClassMethod = CurMethod->isClassMethod(); 1948 1949 bool LookForIvars; 1950 if (Lookup.empty()) 1951 LookForIvars = true; 1952 else if (IsClassMethod) 1953 LookForIvars = false; 1954 else 1955 LookForIvars = (Lookup.isSingleResult() && 1956 Lookup.getFoundDecl()->isDefinedOutsideFunctionOrMethod()); 1957 ObjCInterfaceDecl *IFace = 0; 1958 if (LookForIvars) { 1959 IFace = CurMethod->getClassInterface(); 1960 ObjCInterfaceDecl *ClassDeclared; 1961 ObjCIvarDecl *IV = 0; 1962 if (IFace && (IV = IFace->lookupInstanceVariable(II, ClassDeclared))) { 1963 // Diagnose using an ivar in a class method. 1964 if (IsClassMethod) 1965 return ExprError(Diag(Loc, diag::error_ivar_use_in_class_method) 1966 << IV->getDeclName()); 1967 1968 // If we're referencing an invalid decl, just return this as a silent 1969 // error node. The error diagnostic was already emitted on the decl. 1970 if (IV->isInvalidDecl()) 1971 return ExprError(); 1972 1973 // Check if referencing a field with __attribute__((deprecated)). 1974 if (DiagnoseUseOfDecl(IV, Loc)) 1975 return ExprError(); 1976 1977 // Diagnose the use of an ivar outside of the declaring class. 1978 if (IV->getAccessControl() == ObjCIvarDecl::Private && 1979 !declaresSameEntity(ClassDeclared, IFace)) 1980 Diag(Loc, diag::error_private_ivar_access) << IV->getDeclName(); 1981 1982 // FIXME: This should use a new expr for a direct reference, don't 1983 // turn this into Self->ivar, just return a BareIVarExpr or something. 1984 IdentifierInfo &II = Context.Idents.get("self"); 1985 UnqualifiedId SelfName; 1986 SelfName.setIdentifier(&II, SourceLocation()); 1987 SelfName.setKind(UnqualifiedId::IK_ImplicitSelfParam); 1988 CXXScopeSpec SelfScopeSpec; 1989 ExprResult SelfExpr = ActOnIdExpression(S, SelfScopeSpec, 1990 SelfName, false, false); 1991 if (SelfExpr.isInvalid()) 1992 return ExprError(); 1993 1994 SelfExpr = DefaultLvalueConversion(SelfExpr.take()); 1995 if (SelfExpr.isInvalid()) 1996 return ExprError(); 1997 1998 MarkDeclarationReferenced(Loc, IV); 1999 return Owned(new (Context) 2000 ObjCIvarRefExpr(IV, IV->getType(), Loc, 2001 SelfExpr.take(), true, true)); 2002 } 2003 } else if (CurMethod->isInstanceMethod()) { 2004 // We should warn if a local variable hides an ivar. 2005 if (ObjCInterfaceDecl *IFace = CurMethod->getClassInterface()) { 2006 ObjCInterfaceDecl *ClassDeclared; 2007 if (ObjCIvarDecl *IV = IFace->lookupInstanceVariable(II, ClassDeclared)) { 2008 if (IV->getAccessControl() != ObjCIvarDecl::Private || 2009 declaresSameEntity(IFace, ClassDeclared)) 2010 Diag(Loc, diag::warn_ivar_use_hidden) << IV->getDeclName(); 2011 } 2012 } 2013 } else if (Lookup.isSingleResult() && 2014 Lookup.getFoundDecl()->isDefinedOutsideFunctionOrMethod()) { 2015 // If accessing a stand-alone ivar in a class method, this is an error. 2016 if (const ObjCIvarDecl *IV = dyn_cast<ObjCIvarDecl>(Lookup.getFoundDecl())) 2017 return ExprError(Diag(Loc, diag::error_ivar_use_in_class_method) 2018 << IV->getDeclName()); 2019 } 2020 2021 if (Lookup.empty() && II && AllowBuiltinCreation) { 2022 // FIXME. Consolidate this with similar code in LookupName. 2023 if (unsigned BuiltinID = II->getBuiltinID()) { 2024 if (!(getLangOptions().CPlusPlus && 2025 Context.BuiltinInfo.isPredefinedLibFunction(BuiltinID))) { 2026 NamedDecl *D = LazilyCreateBuiltin((IdentifierInfo *)II, BuiltinID, 2027 S, Lookup.isForRedeclaration(), 2028 Lookup.getNameLoc()); 2029 if (D) Lookup.addDecl(D); 2030 } 2031 } 2032 } 2033 // Sentinel value saying that we didn't do anything special. 2034 return Owned((Expr*) 0); 2035} 2036 2037/// \brief Cast a base object to a member's actual type. 2038/// 2039/// Logically this happens in three phases: 2040/// 2041/// * First we cast from the base type to the naming class. 2042/// The naming class is the class into which we were looking 2043/// when we found the member; it's the qualifier type if a 2044/// qualifier was provided, and otherwise it's the base type. 2045/// 2046/// * Next we cast from the naming class to the declaring class. 2047/// If the member we found was brought into a class's scope by 2048/// a using declaration, this is that class; otherwise it's 2049/// the class declaring the member. 2050/// 2051/// * Finally we cast from the declaring class to the "true" 2052/// declaring class of the member. This conversion does not 2053/// obey access control. 2054ExprResult 2055Sema::PerformObjectMemberConversion(Expr *From, 2056 NestedNameSpecifier *Qualifier, 2057 NamedDecl *FoundDecl, 2058 NamedDecl *Member) { 2059 CXXRecordDecl *RD = dyn_cast<CXXRecordDecl>(Member->getDeclContext()); 2060 if (!RD) 2061 return Owned(From); 2062 2063 QualType DestRecordType; 2064 QualType DestType; 2065 QualType FromRecordType; 2066 QualType FromType = From->getType(); 2067 bool PointerConversions = false; 2068 if (isa<FieldDecl>(Member)) { 2069 DestRecordType = Context.getCanonicalType(Context.getTypeDeclType(RD)); 2070 2071 if (FromType->getAs<PointerType>()) { 2072 DestType = Context.getPointerType(DestRecordType); 2073 FromRecordType = FromType->getPointeeType(); 2074 PointerConversions = true; 2075 } else { 2076 DestType = DestRecordType; 2077 FromRecordType = FromType; 2078 } 2079 } else if (CXXMethodDecl *Method = dyn_cast<CXXMethodDecl>(Member)) { 2080 if (Method->isStatic()) 2081 return Owned(From); 2082 2083 DestType = Method->getThisType(Context); 2084 DestRecordType = DestType->getPointeeType(); 2085 2086 if (FromType->getAs<PointerType>()) { 2087 FromRecordType = FromType->getPointeeType(); 2088 PointerConversions = true; 2089 } else { 2090 FromRecordType = FromType; 2091 DestType = DestRecordType; 2092 } 2093 } else { 2094 // No conversion necessary. 2095 return Owned(From); 2096 } 2097 2098 if (DestType->isDependentType() || FromType->isDependentType()) 2099 return Owned(From); 2100 2101 // If the unqualified types are the same, no conversion is necessary. 2102 if (Context.hasSameUnqualifiedType(FromRecordType, DestRecordType)) 2103 return Owned(From); 2104 2105 SourceRange FromRange = From->getSourceRange(); 2106 SourceLocation FromLoc = FromRange.getBegin(); 2107 2108 ExprValueKind VK = From->getValueKind(); 2109 2110 // C++ [class.member.lookup]p8: 2111 // [...] Ambiguities can often be resolved by qualifying a name with its 2112 // class name. 2113 // 2114 // If the member was a qualified name and the qualified referred to a 2115 // specific base subobject type, we'll cast to that intermediate type 2116 // first and then to the object in which the member is declared. That allows 2117 // one to resolve ambiguities in, e.g., a diamond-shaped hierarchy such as: 2118 // 2119 // class Base { public: int x; }; 2120 // class Derived1 : public Base { }; 2121 // class Derived2 : public Base { }; 2122 // class VeryDerived : public Derived1, public Derived2 { void f(); }; 2123 // 2124 // void VeryDerived::f() { 2125 // x = 17; // error: ambiguous base subobjects 2126 // Derived1::x = 17; // okay, pick the Base subobject of Derived1 2127 // } 2128 if (Qualifier) { 2129 QualType QType = QualType(Qualifier->getAsType(), 0); 2130 assert(!QType.isNull() && "lookup done with dependent qualifier?"); 2131 assert(QType->isRecordType() && "lookup done with non-record type"); 2132 2133 QualType QRecordType = QualType(QType->getAs<RecordType>(), 0); 2134 2135 // In C++98, the qualifier type doesn't actually have to be a base 2136 // type of the object type, in which case we just ignore it. 2137 // Otherwise build the appropriate casts. 2138 if (IsDerivedFrom(FromRecordType, QRecordType)) { 2139 CXXCastPath BasePath; 2140 if (CheckDerivedToBaseConversion(FromRecordType, QRecordType, 2141 FromLoc, FromRange, &BasePath)) 2142 return ExprError(); 2143 2144 if (PointerConversions) 2145 QType = Context.getPointerType(QType); 2146 From = ImpCastExprToType(From, QType, CK_UncheckedDerivedToBase, 2147 VK, &BasePath).take(); 2148 2149 FromType = QType; 2150 FromRecordType = QRecordType; 2151 2152 // If the qualifier type was the same as the destination type, 2153 // we're done. 2154 if (Context.hasSameUnqualifiedType(FromRecordType, DestRecordType)) 2155 return Owned(From); 2156 } 2157 } 2158 2159 bool IgnoreAccess = false; 2160 2161 // If we actually found the member through a using declaration, cast 2162 // down to the using declaration's type. 2163 // 2164 // Pointer equality is fine here because only one declaration of a 2165 // class ever has member declarations. 2166 if (FoundDecl->getDeclContext() != Member->getDeclContext()) { 2167 assert(isa<UsingShadowDecl>(FoundDecl)); 2168 QualType URecordType = Context.getTypeDeclType( 2169 cast<CXXRecordDecl>(FoundDecl->getDeclContext())); 2170 2171 // We only need to do this if the naming-class to declaring-class 2172 // conversion is non-trivial. 2173 if (!Context.hasSameUnqualifiedType(FromRecordType, URecordType)) { 2174 assert(IsDerivedFrom(FromRecordType, URecordType)); 2175 CXXCastPath BasePath; 2176 if (CheckDerivedToBaseConversion(FromRecordType, URecordType, 2177 FromLoc, FromRange, &BasePath)) 2178 return ExprError(); 2179 2180 QualType UType = URecordType; 2181 if (PointerConversions) 2182 UType = Context.getPointerType(UType); 2183 From = ImpCastExprToType(From, UType, CK_UncheckedDerivedToBase, 2184 VK, &BasePath).take(); 2185 FromType = UType; 2186 FromRecordType = URecordType; 2187 } 2188 2189 // We don't do access control for the conversion from the 2190 // declaring class to the true declaring class. 2191 IgnoreAccess = true; 2192 } 2193 2194 CXXCastPath BasePath; 2195 if (CheckDerivedToBaseConversion(FromRecordType, DestRecordType, 2196 FromLoc, FromRange, &BasePath, 2197 IgnoreAccess)) 2198 return ExprError(); 2199 2200 return ImpCastExprToType(From, DestType, CK_UncheckedDerivedToBase, 2201 VK, &BasePath); 2202} 2203 2204bool Sema::UseArgumentDependentLookup(const CXXScopeSpec &SS, 2205 const LookupResult &R, 2206 bool HasTrailingLParen) { 2207 // Only when used directly as the postfix-expression of a call. 2208 if (!HasTrailingLParen) 2209 return false; 2210 2211 // Never if a scope specifier was provided. 2212 if (SS.isSet()) 2213 return false; 2214 2215 // Only in C++ or ObjC++. 2216 if (!getLangOptions().CPlusPlus) 2217 return false; 2218 2219 // Turn off ADL when we find certain kinds of declarations during 2220 // normal lookup: 2221 for (LookupResult::iterator I = R.begin(), E = R.end(); I != E; ++I) { 2222 NamedDecl *D = *I; 2223 2224 // C++0x [basic.lookup.argdep]p3: 2225 // -- a declaration of a class member 2226 // Since using decls preserve this property, we check this on the 2227 // original decl. 2228 if (D->isCXXClassMember()) 2229 return false; 2230 2231 // C++0x [basic.lookup.argdep]p3: 2232 // -- a block-scope function declaration that is not a 2233 // using-declaration 2234 // NOTE: we also trigger this for function templates (in fact, we 2235 // don't check the decl type at all, since all other decl types 2236 // turn off ADL anyway). 2237 if (isa<UsingShadowDecl>(D)) 2238 D = cast<UsingShadowDecl>(D)->getTargetDecl(); 2239 else if (D->getDeclContext()->isFunctionOrMethod()) 2240 return false; 2241 2242 // C++0x [basic.lookup.argdep]p3: 2243 // -- a declaration that is neither a function or a function 2244 // template 2245 // And also for builtin functions. 2246 if (isa<FunctionDecl>(D)) { 2247 FunctionDecl *FDecl = cast<FunctionDecl>(D); 2248 2249 // But also builtin functions. 2250 if (FDecl->getBuiltinID() && FDecl->isImplicit()) 2251 return false; 2252 } else if (!isa<FunctionTemplateDecl>(D)) 2253 return false; 2254 } 2255 2256 return true; 2257} 2258 2259 2260/// Diagnoses obvious problems with the use of the given declaration 2261/// as an expression. This is only actually called for lookups that 2262/// were not overloaded, and it doesn't promise that the declaration 2263/// will in fact be used. 2264static bool CheckDeclInExpr(Sema &S, SourceLocation Loc, NamedDecl *D) { 2265 if (isa<TypedefNameDecl>(D)) { 2266 S.Diag(Loc, diag::err_unexpected_typedef) << D->getDeclName(); 2267 return true; 2268 } 2269 2270 if (isa<ObjCInterfaceDecl>(D)) { 2271 S.Diag(Loc, diag::err_unexpected_interface) << D->getDeclName(); 2272 return true; 2273 } 2274 2275 if (isa<NamespaceDecl>(D)) { 2276 S.Diag(Loc, diag::err_unexpected_namespace) << D->getDeclName(); 2277 return true; 2278 } 2279 2280 return false; 2281} 2282 2283ExprResult 2284Sema::BuildDeclarationNameExpr(const CXXScopeSpec &SS, 2285 LookupResult &R, 2286 bool NeedsADL) { 2287 // If this is a single, fully-resolved result and we don't need ADL, 2288 // just build an ordinary singleton decl ref. 2289 if (!NeedsADL && R.isSingleResult() && !R.getAsSingle<FunctionTemplateDecl>()) 2290 return BuildDeclarationNameExpr(SS, R.getLookupNameInfo(), 2291 R.getFoundDecl()); 2292 2293 // We only need to check the declaration if there's exactly one 2294 // result, because in the overloaded case the results can only be 2295 // functions and function templates. 2296 if (R.isSingleResult() && 2297 CheckDeclInExpr(*this, R.getNameLoc(), R.getFoundDecl())) 2298 return ExprError(); 2299 2300 // Otherwise, just build an unresolved lookup expression. Suppress 2301 // any lookup-related diagnostics; we'll hash these out later, when 2302 // we've picked a target. 2303 R.suppressDiagnostics(); 2304 2305 UnresolvedLookupExpr *ULE 2306 = UnresolvedLookupExpr::Create(Context, R.getNamingClass(), 2307 SS.getWithLocInContext(Context), 2308 R.getLookupNameInfo(), 2309 NeedsADL, R.isOverloadedResult(), 2310 R.begin(), R.end()); 2311 2312 return Owned(ULE); 2313} 2314 2315/// \brief Complete semantic analysis for a reference to the given declaration. 2316ExprResult 2317Sema::BuildDeclarationNameExpr(const CXXScopeSpec &SS, 2318 const DeclarationNameInfo &NameInfo, 2319 NamedDecl *D) { 2320 assert(D && "Cannot refer to a NULL declaration"); 2321 assert(!isa<FunctionTemplateDecl>(D) && 2322 "Cannot refer unambiguously to a function template"); 2323 2324 SourceLocation Loc = NameInfo.getLoc(); 2325 if (CheckDeclInExpr(*this, Loc, D)) 2326 return ExprError(); 2327 2328 if (TemplateDecl *Template = dyn_cast<TemplateDecl>(D)) { 2329 // Specifically diagnose references to class templates that are missing 2330 // a template argument list. 2331 Diag(Loc, diag::err_template_decl_ref) 2332 << Template << SS.getRange(); 2333 Diag(Template->getLocation(), diag::note_template_decl_here); 2334 return ExprError(); 2335 } 2336 2337 // Make sure that we're referring to a value. 2338 ValueDecl *VD = dyn_cast<ValueDecl>(D); 2339 if (!VD) { 2340 Diag(Loc, diag::err_ref_non_value) 2341 << D << SS.getRange(); 2342 Diag(D->getLocation(), diag::note_declared_at); 2343 return ExprError(); 2344 } 2345 2346 // Check whether this declaration can be used. Note that we suppress 2347 // this check when we're going to perform argument-dependent lookup 2348 // on this function name, because this might not be the function 2349 // that overload resolution actually selects. 2350 if (DiagnoseUseOfDecl(VD, Loc)) 2351 return ExprError(); 2352 2353 // Only create DeclRefExpr's for valid Decl's. 2354 if (VD->isInvalidDecl()) 2355 return ExprError(); 2356 2357 // Handle members of anonymous structs and unions. If we got here, 2358 // and the reference is to a class member indirect field, then this 2359 // must be the subject of a pointer-to-member expression. 2360 if (IndirectFieldDecl *indirectField = dyn_cast<IndirectFieldDecl>(VD)) 2361 if (!indirectField->isCXXClassMember()) 2362 return BuildAnonymousStructUnionMemberReference(SS, NameInfo.getLoc(), 2363 indirectField); 2364 2365 // If the identifier reference is inside a block, and it refers to a value 2366 // that is outside the block, create a BlockDeclRefExpr instead of a 2367 // DeclRefExpr. This ensures the value is treated as a copy-in snapshot when 2368 // the block is formed. 2369 // 2370 // We do not do this for things like enum constants, global variables, etc, 2371 // as they do not get snapshotted. 2372 // 2373 switch (shouldCaptureValueReference(*this, NameInfo.getLoc(), VD)) { 2374 case CR_Error: 2375 return ExprError(); 2376 2377 case CR_Capture: 2378 assert(!SS.isSet() && "referenced local variable with scope specifier?"); 2379 return BuildBlockDeclRefExpr(*this, VD, NameInfo, /*byref*/ false); 2380 2381 case CR_CaptureByRef: 2382 assert(!SS.isSet() && "referenced local variable with scope specifier?"); 2383 return BuildBlockDeclRefExpr(*this, VD, NameInfo, /*byref*/ true); 2384 2385 case CR_NoCapture: { 2386 // If this reference is not in a block or if the referenced 2387 // variable is within the block, create a normal DeclRefExpr. 2388 2389 QualType type = VD->getType(); 2390 ExprValueKind valueKind = VK_RValue; 2391 2392 switch (D->getKind()) { 2393 // Ignore all the non-ValueDecl kinds. 2394#define ABSTRACT_DECL(kind) 2395#define VALUE(type, base) 2396#define DECL(type, base) \ 2397 case Decl::type: 2398#include "clang/AST/DeclNodes.inc" 2399 llvm_unreachable("invalid value decl kind"); 2400 return ExprError(); 2401 2402 // These shouldn't make it here. 2403 case Decl::ObjCAtDefsField: 2404 case Decl::ObjCIvar: 2405 llvm_unreachable("forming non-member reference to ivar?"); 2406 return ExprError(); 2407 2408 // Enum constants are always r-values and never references. 2409 // Unresolved using declarations are dependent. 2410 case Decl::EnumConstant: 2411 case Decl::UnresolvedUsingValue: 2412 valueKind = VK_RValue; 2413 break; 2414 2415 // Fields and indirect fields that got here must be for 2416 // pointer-to-member expressions; we just call them l-values for 2417 // internal consistency, because this subexpression doesn't really 2418 // exist in the high-level semantics. 2419 case Decl::Field: 2420 case Decl::IndirectField: 2421 assert(getLangOptions().CPlusPlus && 2422 "building reference to field in C?"); 2423 2424 // These can't have reference type in well-formed programs, but 2425 // for internal consistency we do this anyway. 2426 type = type.getNonReferenceType(); 2427 valueKind = VK_LValue; 2428 break; 2429 2430 // Non-type template parameters are either l-values or r-values 2431 // depending on the type. 2432 case Decl::NonTypeTemplateParm: { 2433 if (const ReferenceType *reftype = type->getAs<ReferenceType>()) { 2434 type = reftype->getPointeeType(); 2435 valueKind = VK_LValue; // even if the parameter is an r-value reference 2436 break; 2437 } 2438 2439 // For non-references, we need to strip qualifiers just in case 2440 // the template parameter was declared as 'const int' or whatever. 2441 valueKind = VK_RValue; 2442 type = type.getUnqualifiedType(); 2443 break; 2444 } 2445 2446 case Decl::Var: 2447 // In C, "extern void blah;" is valid and is an r-value. 2448 if (!getLangOptions().CPlusPlus && 2449 !type.hasQualifiers() && 2450 type->isVoidType()) { 2451 valueKind = VK_RValue; 2452 break; 2453 } 2454 // fallthrough 2455 2456 case Decl::ImplicitParam: 2457 case Decl::ParmVar: 2458 // These are always l-values. 2459 valueKind = VK_LValue; 2460 type = type.getNonReferenceType(); 2461 break; 2462 2463 case Decl::Function: { 2464 const FunctionType *fty = type->castAs<FunctionType>(); 2465 2466 // If we're referring to a function with an __unknown_anytype 2467 // result type, make the entire expression __unknown_anytype. 2468 if (fty->getResultType() == Context.UnknownAnyTy) { 2469 type = Context.UnknownAnyTy; 2470 valueKind = VK_RValue; 2471 break; 2472 } 2473 2474 // Functions are l-values in C++. 2475 if (getLangOptions().CPlusPlus) { 2476 valueKind = VK_LValue; 2477 break; 2478 } 2479 2480 // C99 DR 316 says that, if a function type comes from a 2481 // function definition (without a prototype), that type is only 2482 // used for checking compatibility. Therefore, when referencing 2483 // the function, we pretend that we don't have the full function 2484 // type. 2485 if (!cast<FunctionDecl>(VD)->hasPrototype() && 2486 isa<FunctionProtoType>(fty)) 2487 type = Context.getFunctionNoProtoType(fty->getResultType(), 2488 fty->getExtInfo()); 2489 2490 // Functions are r-values in C. 2491 valueKind = VK_RValue; 2492 break; 2493 } 2494 2495 case Decl::CXXMethod: 2496 // If we're referring to a method with an __unknown_anytype 2497 // result type, make the entire expression __unknown_anytype. 2498 // This should only be possible with a type written directly. 2499 if (const FunctionProtoType *proto 2500 = dyn_cast<FunctionProtoType>(VD->getType())) 2501 if (proto->getResultType() == Context.UnknownAnyTy) { 2502 type = Context.UnknownAnyTy; 2503 valueKind = VK_RValue; 2504 break; 2505 } 2506 2507 // C++ methods are l-values if static, r-values if non-static. 2508 if (cast<CXXMethodDecl>(VD)->isStatic()) { 2509 valueKind = VK_LValue; 2510 break; 2511 } 2512 // fallthrough 2513 2514 case Decl::CXXConversion: 2515 case Decl::CXXDestructor: 2516 case Decl::CXXConstructor: 2517 valueKind = VK_RValue; 2518 break; 2519 } 2520 2521 return BuildDeclRefExpr(VD, type, valueKind, NameInfo, &SS); 2522 } 2523 2524 } 2525 2526 llvm_unreachable("unknown capture result"); 2527 return ExprError(); 2528} 2529 2530ExprResult Sema::ActOnPredefinedExpr(SourceLocation Loc, tok::TokenKind Kind) { 2531 PredefinedExpr::IdentType IT; 2532 2533 switch (Kind) { 2534 default: llvm_unreachable("Unknown simple primary expr!"); 2535 case tok::kw___func__: IT = PredefinedExpr::Func; break; // [C99 6.4.2.2] 2536 case tok::kw___FUNCTION__: IT = PredefinedExpr::Function; break; 2537 case tok::kw___PRETTY_FUNCTION__: IT = PredefinedExpr::PrettyFunction; break; 2538 } 2539 2540 // Pre-defined identifiers are of type char[x], where x is the length of the 2541 // string. 2542 2543 Decl *currentDecl = getCurFunctionOrMethodDecl(); 2544 if (!currentDecl && getCurBlock()) 2545 currentDecl = getCurBlock()->TheDecl; 2546 if (!currentDecl) { 2547 Diag(Loc, diag::ext_predef_outside_function); 2548 currentDecl = Context.getTranslationUnitDecl(); 2549 } 2550 2551 QualType ResTy; 2552 if (cast<DeclContext>(currentDecl)->isDependentContext()) { 2553 ResTy = Context.DependentTy; 2554 } else { 2555 unsigned Length = PredefinedExpr::ComputeName(IT, currentDecl).length(); 2556 2557 llvm::APInt LengthI(32, Length + 1); 2558 ResTy = Context.CharTy.withConst(); 2559 ResTy = Context.getConstantArrayType(ResTy, LengthI, ArrayType::Normal, 0); 2560 } 2561 return Owned(new (Context) PredefinedExpr(Loc, ResTy, IT)); 2562} 2563 2564ExprResult Sema::ActOnCharacterConstant(const Token &Tok) { 2565 llvm::SmallString<16> CharBuffer; 2566 bool Invalid = false; 2567 StringRef ThisTok = PP.getSpelling(Tok, CharBuffer, &Invalid); 2568 if (Invalid) 2569 return ExprError(); 2570 2571 CharLiteralParser Literal(ThisTok.begin(), ThisTok.end(), Tok.getLocation(), 2572 PP, Tok.getKind()); 2573 if (Literal.hadError()) 2574 return ExprError(); 2575 2576 QualType Ty; 2577 if (!getLangOptions().CPlusPlus) 2578 Ty = Context.IntTy; // 'x' and L'x' -> int in C. 2579 else if (Literal.isWide()) 2580 Ty = Context.WCharTy; // L'x' -> wchar_t in C++. 2581 else if (Literal.isUTF16()) 2582 Ty = Context.Char16Ty; // u'x' -> char16_t in C++0x. 2583 else if (Literal.isUTF32()) 2584 Ty = Context.Char32Ty; // U'x' -> char32_t in C++0x. 2585 else if (Literal.isMultiChar()) 2586 Ty = Context.IntTy; // 'wxyz' -> int in C++. 2587 else 2588 Ty = Context.CharTy; // 'x' -> char in C++ 2589 2590 CharacterLiteral::CharacterKind Kind = CharacterLiteral::Ascii; 2591 if (Literal.isWide()) 2592 Kind = CharacterLiteral::Wide; 2593 else if (Literal.isUTF16()) 2594 Kind = CharacterLiteral::UTF16; 2595 else if (Literal.isUTF32()) 2596 Kind = CharacterLiteral::UTF32; 2597 2598 return Owned(new (Context) CharacterLiteral(Literal.getValue(), Kind, Ty, 2599 Tok.getLocation())); 2600} 2601 2602ExprResult Sema::ActOnNumericConstant(const Token &Tok) { 2603 // Fast path for a single digit (which is quite common). A single digit 2604 // cannot have a trigraph, escaped newline, radix prefix, or type suffix. 2605 if (Tok.getLength() == 1) { 2606 const char Val = PP.getSpellingOfSingleCharacterNumericConstant(Tok); 2607 unsigned IntSize = Context.getTargetInfo().getIntWidth(); 2608 return Owned(IntegerLiteral::Create(Context, llvm::APInt(IntSize, Val-'0'), 2609 Context.IntTy, Tok.getLocation())); 2610 } 2611 2612 llvm::SmallString<512> IntegerBuffer; 2613 // Add padding so that NumericLiteralParser can overread by one character. 2614 IntegerBuffer.resize(Tok.getLength()+1); 2615 const char *ThisTokBegin = &IntegerBuffer[0]; 2616 2617 // Get the spelling of the token, which eliminates trigraphs, etc. 2618 bool Invalid = false; 2619 unsigned ActualLength = PP.getSpelling(Tok, ThisTokBegin, &Invalid); 2620 if (Invalid) 2621 return ExprError(); 2622 2623 NumericLiteralParser Literal(ThisTokBegin, ThisTokBegin+ActualLength, 2624 Tok.getLocation(), PP); 2625 if (Literal.hadError) 2626 return ExprError(); 2627 2628 Expr *Res; 2629 2630 if (Literal.isFloatingLiteral()) { 2631 QualType Ty; 2632 if (Literal.isFloat) 2633 Ty = Context.FloatTy; 2634 else if (!Literal.isLong) 2635 Ty = Context.DoubleTy; 2636 else 2637 Ty = Context.LongDoubleTy; 2638 2639 const llvm::fltSemantics &Format = Context.getFloatTypeSemantics(Ty); 2640 2641 using llvm::APFloat; 2642 APFloat Val(Format); 2643 2644 APFloat::opStatus result = Literal.GetFloatValue(Val); 2645 2646 // Overflow is always an error, but underflow is only an error if 2647 // we underflowed to zero (APFloat reports denormals as underflow). 2648 if ((result & APFloat::opOverflow) || 2649 ((result & APFloat::opUnderflow) && Val.isZero())) { 2650 unsigned diagnostic; 2651 llvm::SmallString<20> buffer; 2652 if (result & APFloat::opOverflow) { 2653 diagnostic = diag::warn_float_overflow; 2654 APFloat::getLargest(Format).toString(buffer); 2655 } else { 2656 diagnostic = diag::warn_float_underflow; 2657 APFloat::getSmallest(Format).toString(buffer); 2658 } 2659 2660 Diag(Tok.getLocation(), diagnostic) 2661 << Ty 2662 << StringRef(buffer.data(), buffer.size()); 2663 } 2664 2665 bool isExact = (result == APFloat::opOK); 2666 Res = FloatingLiteral::Create(Context, Val, isExact, Ty, Tok.getLocation()); 2667 2668 if (Ty == Context.DoubleTy) { 2669 if (getLangOptions().SinglePrecisionConstants) { 2670 Res = ImpCastExprToType(Res, Context.FloatTy, CK_FloatingCast).take(); 2671 } else if (getLangOptions().OpenCL && !getOpenCLOptions().cl_khr_fp64) { 2672 Diag(Tok.getLocation(), diag::warn_double_const_requires_fp64); 2673 Res = ImpCastExprToType(Res, Context.FloatTy, CK_FloatingCast).take(); 2674 } 2675 } 2676 } else if (!Literal.isIntegerLiteral()) { 2677 return ExprError(); 2678 } else { 2679 QualType Ty; 2680 2681 // long long is a C99 feature. 2682 if (!getLangOptions().C99 && Literal.isLongLong) 2683 Diag(Tok.getLocation(), 2684 getLangOptions().CPlusPlus0x ? 2685 diag::warn_cxx98_compat_longlong : diag::ext_longlong); 2686 2687 // Get the value in the widest-possible width. 2688 llvm::APInt ResultVal(Context.getTargetInfo().getIntMaxTWidth(), 0); 2689 2690 if (Literal.GetIntegerValue(ResultVal)) { 2691 // If this value didn't fit into uintmax_t, warn and force to ull. 2692 Diag(Tok.getLocation(), diag::warn_integer_too_large); 2693 Ty = Context.UnsignedLongLongTy; 2694 assert(Context.getTypeSize(Ty) == ResultVal.getBitWidth() && 2695 "long long is not intmax_t?"); 2696 } else { 2697 // If this value fits into a ULL, try to figure out what else it fits into 2698 // according to the rules of C99 6.4.4.1p5. 2699 2700 // Octal, Hexadecimal, and integers with a U suffix are allowed to 2701 // be an unsigned int. 2702 bool AllowUnsigned = Literal.isUnsigned || Literal.getRadix() != 10; 2703 2704 // Check from smallest to largest, picking the smallest type we can. 2705 unsigned Width = 0; 2706 if (!Literal.isLong && !Literal.isLongLong) { 2707 // Are int/unsigned possibilities? 2708 unsigned IntSize = Context.getTargetInfo().getIntWidth(); 2709 2710 // Does it fit in a unsigned int? 2711 if (ResultVal.isIntN(IntSize)) { 2712 // Does it fit in a signed int? 2713 if (!Literal.isUnsigned && ResultVal[IntSize-1] == 0) 2714 Ty = Context.IntTy; 2715 else if (AllowUnsigned) 2716 Ty = Context.UnsignedIntTy; 2717 Width = IntSize; 2718 } 2719 } 2720 2721 // Are long/unsigned long possibilities? 2722 if (Ty.isNull() && !Literal.isLongLong) { 2723 unsigned LongSize = Context.getTargetInfo().getLongWidth(); 2724 2725 // Does it fit in a unsigned long? 2726 if (ResultVal.isIntN(LongSize)) { 2727 // Does it fit in a signed long? 2728 if (!Literal.isUnsigned && ResultVal[LongSize-1] == 0) 2729 Ty = Context.LongTy; 2730 else if (AllowUnsigned) 2731 Ty = Context.UnsignedLongTy; 2732 Width = LongSize; 2733 } 2734 } 2735 2736 // Finally, check long long if needed. 2737 if (Ty.isNull()) { 2738 unsigned LongLongSize = Context.getTargetInfo().getLongLongWidth(); 2739 2740 // Does it fit in a unsigned long long? 2741 if (ResultVal.isIntN(LongLongSize)) { 2742 // Does it fit in a signed long long? 2743 // To be compatible with MSVC, hex integer literals ending with the 2744 // LL or i64 suffix are always signed in Microsoft mode. 2745 if (!Literal.isUnsigned && (ResultVal[LongLongSize-1] == 0 || 2746 (getLangOptions().MicrosoftExt && Literal.isLongLong))) 2747 Ty = Context.LongLongTy; 2748 else if (AllowUnsigned) 2749 Ty = Context.UnsignedLongLongTy; 2750 Width = LongLongSize; 2751 } 2752 } 2753 2754 // If we still couldn't decide a type, we probably have something that 2755 // does not fit in a signed long long, but has no U suffix. 2756 if (Ty.isNull()) { 2757 Diag(Tok.getLocation(), diag::warn_integer_too_large_for_signed); 2758 Ty = Context.UnsignedLongLongTy; 2759 Width = Context.getTargetInfo().getLongLongWidth(); 2760 } 2761 2762 if (ResultVal.getBitWidth() != Width) 2763 ResultVal = ResultVal.trunc(Width); 2764 } 2765 Res = IntegerLiteral::Create(Context, ResultVal, Ty, Tok.getLocation()); 2766 } 2767 2768 // If this is an imaginary literal, create the ImaginaryLiteral wrapper. 2769 if (Literal.isImaginary) 2770 Res = new (Context) ImaginaryLiteral(Res, 2771 Context.getComplexType(Res->getType())); 2772 2773 return Owned(Res); 2774} 2775 2776ExprResult Sema::ActOnParenExpr(SourceLocation L, SourceLocation R, Expr *E) { 2777 assert((E != 0) && "ActOnParenExpr() missing expr"); 2778 return Owned(new (Context) ParenExpr(L, R, E)); 2779} 2780 2781static bool CheckVecStepTraitOperandType(Sema &S, QualType T, 2782 SourceLocation Loc, 2783 SourceRange ArgRange) { 2784 // [OpenCL 1.1 6.11.12] "The vec_step built-in function takes a built-in 2785 // scalar or vector data type argument..." 2786 // Every built-in scalar type (OpenCL 1.1 6.1.1) is either an arithmetic 2787 // type (C99 6.2.5p18) or void. 2788 if (!(T->isArithmeticType() || T->isVoidType() || T->isVectorType())) { 2789 S.Diag(Loc, diag::err_vecstep_non_scalar_vector_type) 2790 << T << ArgRange; 2791 return true; 2792 } 2793 2794 assert((T->isVoidType() || !T->isIncompleteType()) && 2795 "Scalar types should always be complete"); 2796 return false; 2797} 2798 2799static bool CheckExtensionTraitOperandType(Sema &S, QualType T, 2800 SourceLocation Loc, 2801 SourceRange ArgRange, 2802 UnaryExprOrTypeTrait TraitKind) { 2803 // C99 6.5.3.4p1: 2804 if (T->isFunctionType()) { 2805 // alignof(function) is allowed as an extension. 2806 if (TraitKind == UETT_SizeOf) 2807 S.Diag(Loc, diag::ext_sizeof_function_type) << ArgRange; 2808 return false; 2809 } 2810 2811 // Allow sizeof(void)/alignof(void) as an extension. 2812 if (T->isVoidType()) { 2813 S.Diag(Loc, diag::ext_sizeof_void_type) << TraitKind << ArgRange; 2814 return false; 2815 } 2816 2817 return true; 2818} 2819 2820static bool CheckObjCTraitOperandConstraints(Sema &S, QualType T, 2821 SourceLocation Loc, 2822 SourceRange ArgRange, 2823 UnaryExprOrTypeTrait TraitKind) { 2824 // Reject sizeof(interface) and sizeof(interface<proto>) in 64-bit mode. 2825 if (S.LangOpts.ObjCNonFragileABI && T->isObjCObjectType()) { 2826 S.Diag(Loc, diag::err_sizeof_nonfragile_interface) 2827 << T << (TraitKind == UETT_SizeOf) 2828 << ArgRange; 2829 return true; 2830 } 2831 2832 return false; 2833} 2834 2835/// \brief Check the constrains on expression operands to unary type expression 2836/// and type traits. 2837/// 2838/// Completes any types necessary and validates the constraints on the operand 2839/// expression. The logic mostly mirrors the type-based overload, but may modify 2840/// the expression as it completes the type for that expression through template 2841/// instantiation, etc. 2842bool Sema::CheckUnaryExprOrTypeTraitOperand(Expr *E, 2843 UnaryExprOrTypeTrait ExprKind) { 2844 QualType ExprTy = E->getType(); 2845 2846 // C++ [expr.sizeof]p2: "When applied to a reference or a reference type, 2847 // the result is the size of the referenced type." 2848 // C++ [expr.alignof]p3: "When alignof is applied to a reference type, the 2849 // result shall be the alignment of the referenced type." 2850 if (const ReferenceType *Ref = ExprTy->getAs<ReferenceType>()) 2851 ExprTy = Ref->getPointeeType(); 2852 2853 if (ExprKind == UETT_VecStep) 2854 return CheckVecStepTraitOperandType(*this, ExprTy, E->getExprLoc(), 2855 E->getSourceRange()); 2856 2857 // Whitelist some types as extensions 2858 if (!CheckExtensionTraitOperandType(*this, ExprTy, E->getExprLoc(), 2859 E->getSourceRange(), ExprKind)) 2860 return false; 2861 2862 if (RequireCompleteExprType(E, 2863 PDiag(diag::err_sizeof_alignof_incomplete_type) 2864 << ExprKind << E->getSourceRange(), 2865 std::make_pair(SourceLocation(), PDiag(0)))) 2866 return true; 2867 2868 // Completeing the expression's type may have changed it. 2869 ExprTy = E->getType(); 2870 if (const ReferenceType *Ref = ExprTy->getAs<ReferenceType>()) 2871 ExprTy = Ref->getPointeeType(); 2872 2873 if (CheckObjCTraitOperandConstraints(*this, ExprTy, E->getExprLoc(), 2874 E->getSourceRange(), ExprKind)) 2875 return true; 2876 2877 if (ExprKind == UETT_SizeOf) { 2878 if (DeclRefExpr *DeclRef = dyn_cast<DeclRefExpr>(E->IgnoreParens())) { 2879 if (ParmVarDecl *PVD = dyn_cast<ParmVarDecl>(DeclRef->getFoundDecl())) { 2880 QualType OType = PVD->getOriginalType(); 2881 QualType Type = PVD->getType(); 2882 if (Type->isPointerType() && OType->isArrayType()) { 2883 Diag(E->getExprLoc(), diag::warn_sizeof_array_param) 2884 << Type << OType; 2885 Diag(PVD->getLocation(), diag::note_declared_at); 2886 } 2887 } 2888 } 2889 } 2890 2891 return false; 2892} 2893 2894/// \brief Check the constraints on operands to unary expression and type 2895/// traits. 2896/// 2897/// This will complete any types necessary, and validate the various constraints 2898/// on those operands. 2899/// 2900/// The UsualUnaryConversions() function is *not* called by this routine. 2901/// C99 6.3.2.1p[2-4] all state: 2902/// Except when it is the operand of the sizeof operator ... 2903/// 2904/// C++ [expr.sizeof]p4 2905/// The lvalue-to-rvalue, array-to-pointer, and function-to-pointer 2906/// standard conversions are not applied to the operand of sizeof. 2907/// 2908/// This policy is followed for all of the unary trait expressions. 2909bool Sema::CheckUnaryExprOrTypeTraitOperand(QualType ExprType, 2910 SourceLocation OpLoc, 2911 SourceRange ExprRange, 2912 UnaryExprOrTypeTrait ExprKind) { 2913 if (ExprType->isDependentType()) 2914 return false; 2915 2916 // C++ [expr.sizeof]p2: "When applied to a reference or a reference type, 2917 // the result is the size of the referenced type." 2918 // C++ [expr.alignof]p3: "When alignof is applied to a reference type, the 2919 // result shall be the alignment of the referenced type." 2920 if (const ReferenceType *Ref = ExprType->getAs<ReferenceType>()) 2921 ExprType = Ref->getPointeeType(); 2922 2923 if (ExprKind == UETT_VecStep) 2924 return CheckVecStepTraitOperandType(*this, ExprType, OpLoc, ExprRange); 2925 2926 // Whitelist some types as extensions 2927 if (!CheckExtensionTraitOperandType(*this, ExprType, OpLoc, ExprRange, 2928 ExprKind)) 2929 return false; 2930 2931 if (RequireCompleteType(OpLoc, ExprType, 2932 PDiag(diag::err_sizeof_alignof_incomplete_type) 2933 << ExprKind << ExprRange)) 2934 return true; 2935 2936 if (CheckObjCTraitOperandConstraints(*this, ExprType, OpLoc, ExprRange, 2937 ExprKind)) 2938 return true; 2939 2940 return false; 2941} 2942 2943static bool CheckAlignOfExpr(Sema &S, Expr *E) { 2944 E = E->IgnoreParens(); 2945 2946 // alignof decl is always ok. 2947 if (isa<DeclRefExpr>(E)) 2948 return false; 2949 2950 // Cannot know anything else if the expression is dependent. 2951 if (E->isTypeDependent()) 2952 return false; 2953 2954 if (E->getBitField()) { 2955 S.Diag(E->getExprLoc(), diag::err_sizeof_alignof_bitfield) 2956 << 1 << E->getSourceRange(); 2957 return true; 2958 } 2959 2960 // Alignment of a field access is always okay, so long as it isn't a 2961 // bit-field. 2962 if (MemberExpr *ME = dyn_cast<MemberExpr>(E)) 2963 if (isa<FieldDecl>(ME->getMemberDecl())) 2964 return false; 2965 2966 return S.CheckUnaryExprOrTypeTraitOperand(E, UETT_AlignOf); 2967} 2968 2969bool Sema::CheckVecStepExpr(Expr *E) { 2970 E = E->IgnoreParens(); 2971 2972 // Cannot know anything else if the expression is dependent. 2973 if (E->isTypeDependent()) 2974 return false; 2975 2976 return CheckUnaryExprOrTypeTraitOperand(E, UETT_VecStep); 2977} 2978 2979/// \brief Build a sizeof or alignof expression given a type operand. 2980ExprResult 2981Sema::CreateUnaryExprOrTypeTraitExpr(TypeSourceInfo *TInfo, 2982 SourceLocation OpLoc, 2983 UnaryExprOrTypeTrait ExprKind, 2984 SourceRange R) { 2985 if (!TInfo) 2986 return ExprError(); 2987 2988 QualType T = TInfo->getType(); 2989 2990 if (!T->isDependentType() && 2991 CheckUnaryExprOrTypeTraitOperand(T, OpLoc, R, ExprKind)) 2992 return ExprError(); 2993 2994 // C99 6.5.3.4p4: the type (an unsigned integer type) is size_t. 2995 return Owned(new (Context) UnaryExprOrTypeTraitExpr(ExprKind, TInfo, 2996 Context.getSizeType(), 2997 OpLoc, R.getEnd())); 2998} 2999 3000/// \brief Build a sizeof or alignof expression given an expression 3001/// operand. 3002ExprResult 3003Sema::CreateUnaryExprOrTypeTraitExpr(Expr *E, SourceLocation OpLoc, 3004 UnaryExprOrTypeTrait ExprKind) { 3005 ExprResult PE = CheckPlaceholderExpr(E); 3006 if (PE.isInvalid()) 3007 return ExprError(); 3008 3009 E = PE.get(); 3010 3011 // Verify that the operand is valid. 3012 bool isInvalid = false; 3013 if (E->isTypeDependent()) { 3014 // Delay type-checking for type-dependent expressions. 3015 } else if (ExprKind == UETT_AlignOf) { 3016 isInvalid = CheckAlignOfExpr(*this, E); 3017 } else if (ExprKind == UETT_VecStep) { 3018 isInvalid = CheckVecStepExpr(E); 3019 } else if (E->getBitField()) { // C99 6.5.3.4p1. 3020 Diag(E->getExprLoc(), diag::err_sizeof_alignof_bitfield) << 0; 3021 isInvalid = true; 3022 } else { 3023 isInvalid = CheckUnaryExprOrTypeTraitOperand(E, UETT_SizeOf); 3024 } 3025 3026 if (isInvalid) 3027 return ExprError(); 3028 3029 // C99 6.5.3.4p4: the type (an unsigned integer type) is size_t. 3030 return Owned(new (Context) UnaryExprOrTypeTraitExpr( 3031 ExprKind, E, Context.getSizeType(), OpLoc, 3032 E->getSourceRange().getEnd())); 3033} 3034 3035/// ActOnUnaryExprOrTypeTraitExpr - Handle @c sizeof(type) and @c sizeof @c 3036/// expr and the same for @c alignof and @c __alignof 3037/// Note that the ArgRange is invalid if isType is false. 3038ExprResult 3039Sema::ActOnUnaryExprOrTypeTraitExpr(SourceLocation OpLoc, 3040 UnaryExprOrTypeTrait ExprKind, bool IsType, 3041 void *TyOrEx, const SourceRange &ArgRange) { 3042 // If error parsing type, ignore. 3043 if (TyOrEx == 0) return ExprError(); 3044 3045 if (IsType) { 3046 TypeSourceInfo *TInfo; 3047 (void) GetTypeFromParser(ParsedType::getFromOpaquePtr(TyOrEx), &TInfo); 3048 return CreateUnaryExprOrTypeTraitExpr(TInfo, OpLoc, ExprKind, ArgRange); 3049 } 3050 3051 Expr *ArgEx = (Expr *)TyOrEx; 3052 ExprResult Result = CreateUnaryExprOrTypeTraitExpr(ArgEx, OpLoc, ExprKind); 3053 return move(Result); 3054} 3055 3056static QualType CheckRealImagOperand(Sema &S, ExprResult &V, SourceLocation Loc, 3057 bool IsReal) { 3058 if (V.get()->isTypeDependent()) 3059 return S.Context.DependentTy; 3060 3061 // _Real and _Imag are only l-values for normal l-values. 3062 if (V.get()->getObjectKind() != OK_Ordinary) { 3063 V = S.DefaultLvalueConversion(V.take()); 3064 if (V.isInvalid()) 3065 return QualType(); 3066 } 3067 3068 // These operators return the element type of a complex type. 3069 if (const ComplexType *CT = V.get()->getType()->getAs<ComplexType>()) 3070 return CT->getElementType(); 3071 3072 // Otherwise they pass through real integer and floating point types here. 3073 if (V.get()->getType()->isArithmeticType()) 3074 return V.get()->getType(); 3075 3076 // Test for placeholders. 3077 ExprResult PR = S.CheckPlaceholderExpr(V.get()); 3078 if (PR.isInvalid()) return QualType(); 3079 if (PR.get() != V.get()) { 3080 V = move(PR); 3081 return CheckRealImagOperand(S, V, Loc, IsReal); 3082 } 3083 3084 // Reject anything else. 3085 S.Diag(Loc, diag::err_realimag_invalid_type) << V.get()->getType() 3086 << (IsReal ? "__real" : "__imag"); 3087 return QualType(); 3088} 3089 3090 3091 3092ExprResult 3093Sema::ActOnPostfixUnaryOp(Scope *S, SourceLocation OpLoc, 3094 tok::TokenKind Kind, Expr *Input) { 3095 UnaryOperatorKind Opc; 3096 switch (Kind) { 3097 default: llvm_unreachable("Unknown unary op!"); 3098 case tok::plusplus: Opc = UO_PostInc; break; 3099 case tok::minusminus: Opc = UO_PostDec; break; 3100 } 3101 3102 return BuildUnaryOp(S, OpLoc, Opc, Input); 3103} 3104 3105ExprResult 3106Sema::ActOnArraySubscriptExpr(Scope *S, Expr *Base, SourceLocation LLoc, 3107 Expr *Idx, SourceLocation RLoc) { 3108 // Since this might be a postfix expression, get rid of ParenListExprs. 3109 ExprResult Result = MaybeConvertParenListExprToParenExpr(S, Base); 3110 if (Result.isInvalid()) return ExprError(); 3111 Base = Result.take(); 3112 3113 Expr *LHSExp = Base, *RHSExp = Idx; 3114 3115 if (getLangOptions().CPlusPlus && 3116 (LHSExp->isTypeDependent() || RHSExp->isTypeDependent())) { 3117 return Owned(new (Context) ArraySubscriptExpr(LHSExp, RHSExp, 3118 Context.DependentTy, 3119 VK_LValue, OK_Ordinary, 3120 RLoc)); 3121 } 3122 3123 if (getLangOptions().CPlusPlus && 3124 (LHSExp->getType()->isRecordType() || 3125 LHSExp->getType()->isEnumeralType() || 3126 RHSExp->getType()->isRecordType() || 3127 RHSExp->getType()->isEnumeralType())) { 3128 return CreateOverloadedArraySubscriptExpr(LLoc, RLoc, Base, Idx); 3129 } 3130 3131 return CreateBuiltinArraySubscriptExpr(Base, LLoc, Idx, RLoc); 3132} 3133 3134 3135ExprResult 3136Sema::CreateBuiltinArraySubscriptExpr(Expr *Base, SourceLocation LLoc, 3137 Expr *Idx, SourceLocation RLoc) { 3138 Expr *LHSExp = Base; 3139 Expr *RHSExp = Idx; 3140 3141 // Perform default conversions. 3142 if (!LHSExp->getType()->getAs<VectorType>()) { 3143 ExprResult Result = DefaultFunctionArrayLvalueConversion(LHSExp); 3144 if (Result.isInvalid()) 3145 return ExprError(); 3146 LHSExp = Result.take(); 3147 } 3148 ExprResult Result = DefaultFunctionArrayLvalueConversion(RHSExp); 3149 if (Result.isInvalid()) 3150 return ExprError(); 3151 RHSExp = Result.take(); 3152 3153 QualType LHSTy = LHSExp->getType(), RHSTy = RHSExp->getType(); 3154 ExprValueKind VK = VK_LValue; 3155 ExprObjectKind OK = OK_Ordinary; 3156 3157 // C99 6.5.2.1p2: the expression e1[e2] is by definition precisely equivalent 3158 // to the expression *((e1)+(e2)). This means the array "Base" may actually be 3159 // in the subscript position. As a result, we need to derive the array base 3160 // and index from the expression types. 3161 Expr *BaseExpr, *IndexExpr; 3162 QualType ResultType; 3163 if (LHSTy->isDependentType() || RHSTy->isDependentType()) { 3164 BaseExpr = LHSExp; 3165 IndexExpr = RHSExp; 3166 ResultType = Context.DependentTy; 3167 } else if (const PointerType *PTy = LHSTy->getAs<PointerType>()) { 3168 BaseExpr = LHSExp; 3169 IndexExpr = RHSExp; 3170 ResultType = PTy->getPointeeType(); 3171 } else if (const PointerType *PTy = RHSTy->getAs<PointerType>()) { 3172 // Handle the uncommon case of "123[Ptr]". 3173 BaseExpr = RHSExp; 3174 IndexExpr = LHSExp; 3175 ResultType = PTy->getPointeeType(); 3176 } else if (const ObjCObjectPointerType *PTy = 3177 LHSTy->getAs<ObjCObjectPointerType>()) { 3178 BaseExpr = LHSExp; 3179 IndexExpr = RHSExp; 3180 ResultType = PTy->getPointeeType(); 3181 } else if (const ObjCObjectPointerType *PTy = 3182 RHSTy->getAs<ObjCObjectPointerType>()) { 3183 // Handle the uncommon case of "123[Ptr]". 3184 BaseExpr = RHSExp; 3185 IndexExpr = LHSExp; 3186 ResultType = PTy->getPointeeType(); 3187 } else if (const VectorType *VTy = LHSTy->getAs<VectorType>()) { 3188 BaseExpr = LHSExp; // vectors: V[123] 3189 IndexExpr = RHSExp; 3190 VK = LHSExp->getValueKind(); 3191 if (VK != VK_RValue) 3192 OK = OK_VectorComponent; 3193 3194 // FIXME: need to deal with const... 3195 ResultType = VTy->getElementType(); 3196 } else if (LHSTy->isArrayType()) { 3197 // If we see an array that wasn't promoted by 3198 // DefaultFunctionArrayLvalueConversion, it must be an array that 3199 // wasn't promoted because of the C90 rule that doesn't 3200 // allow promoting non-lvalue arrays. Warn, then 3201 // force the promotion here. 3202 Diag(LHSExp->getLocStart(), diag::ext_subscript_non_lvalue) << 3203 LHSExp->getSourceRange(); 3204 LHSExp = ImpCastExprToType(LHSExp, Context.getArrayDecayedType(LHSTy), 3205 CK_ArrayToPointerDecay).take(); 3206 LHSTy = LHSExp->getType(); 3207 3208 BaseExpr = LHSExp; 3209 IndexExpr = RHSExp; 3210 ResultType = LHSTy->getAs<PointerType>()->getPointeeType(); 3211 } else if (RHSTy->isArrayType()) { 3212 // Same as previous, except for 123[f().a] case 3213 Diag(RHSExp->getLocStart(), diag::ext_subscript_non_lvalue) << 3214 RHSExp->getSourceRange(); 3215 RHSExp = ImpCastExprToType(RHSExp, Context.getArrayDecayedType(RHSTy), 3216 CK_ArrayToPointerDecay).take(); 3217 RHSTy = RHSExp->getType(); 3218 3219 BaseExpr = RHSExp; 3220 IndexExpr = LHSExp; 3221 ResultType = RHSTy->getAs<PointerType>()->getPointeeType(); 3222 } else { 3223 return ExprError(Diag(LLoc, diag::err_typecheck_subscript_value) 3224 << LHSExp->getSourceRange() << RHSExp->getSourceRange()); 3225 } 3226 // C99 6.5.2.1p1 3227 if (!IndexExpr->getType()->isIntegerType() && !IndexExpr->isTypeDependent()) 3228 return ExprError(Diag(LLoc, diag::err_typecheck_subscript_not_integer) 3229 << IndexExpr->getSourceRange()); 3230 3231 if ((IndexExpr->getType()->isSpecificBuiltinType(BuiltinType::Char_S) || 3232 IndexExpr->getType()->isSpecificBuiltinType(BuiltinType::Char_U)) 3233 && !IndexExpr->isTypeDependent()) 3234 Diag(LLoc, diag::warn_subscript_is_char) << IndexExpr->getSourceRange(); 3235 3236 // C99 6.5.2.1p1: "shall have type "pointer to *object* type". Similarly, 3237 // C++ [expr.sub]p1: The type "T" shall be a completely-defined object 3238 // type. Note that Functions are not objects, and that (in C99 parlance) 3239 // incomplete types are not object types. 3240 if (ResultType->isFunctionType()) { 3241 Diag(BaseExpr->getLocStart(), diag::err_subscript_function_type) 3242 << ResultType << BaseExpr->getSourceRange(); 3243 return ExprError(); 3244 } 3245 3246 if (ResultType->isVoidType() && !getLangOptions().CPlusPlus) { 3247 // GNU extension: subscripting on pointer to void 3248 Diag(LLoc, diag::ext_gnu_subscript_void_type) 3249 << BaseExpr->getSourceRange(); 3250 3251 // C forbids expressions of unqualified void type from being l-values. 3252 // See IsCForbiddenLValueType. 3253 if (!ResultType.hasQualifiers()) VK = VK_RValue; 3254 } else if (!ResultType->isDependentType() && 3255 RequireCompleteType(LLoc, ResultType, 3256 PDiag(diag::err_subscript_incomplete_type) 3257 << BaseExpr->getSourceRange())) 3258 return ExprError(); 3259 3260 // Diagnose bad cases where we step over interface counts. 3261 if (ResultType->isObjCObjectType() && LangOpts.ObjCNonFragileABI) { 3262 Diag(LLoc, diag::err_subscript_nonfragile_interface) 3263 << ResultType << BaseExpr->getSourceRange(); 3264 return ExprError(); 3265 } 3266 3267 assert(VK == VK_RValue || LangOpts.CPlusPlus || 3268 !ResultType.isCForbiddenLValueType()); 3269 3270 return Owned(new (Context) ArraySubscriptExpr(LHSExp, RHSExp, 3271 ResultType, VK, OK, RLoc)); 3272} 3273 3274ExprResult Sema::BuildCXXDefaultArgExpr(SourceLocation CallLoc, 3275 FunctionDecl *FD, 3276 ParmVarDecl *Param) { 3277 if (Param->hasUnparsedDefaultArg()) { 3278 Diag(CallLoc, 3279 diag::err_use_of_default_argument_to_function_declared_later) << 3280 FD << cast<CXXRecordDecl>(FD->getDeclContext())->getDeclName(); 3281 Diag(UnparsedDefaultArgLocs[Param], 3282 diag::note_default_argument_declared_here); 3283 return ExprError(); 3284 } 3285 3286 if (Param->hasUninstantiatedDefaultArg()) { 3287 Expr *UninstExpr = Param->getUninstantiatedDefaultArg(); 3288 3289 // Instantiate the expression. 3290 MultiLevelTemplateArgumentList ArgList 3291 = getTemplateInstantiationArgs(FD, 0, /*RelativeToPrimary=*/true); 3292 3293 std::pair<const TemplateArgument *, unsigned> Innermost 3294 = ArgList.getInnermost(); 3295 InstantiatingTemplate Inst(*this, CallLoc, Param, Innermost.first, 3296 Innermost.second); 3297 3298 ExprResult Result; 3299 { 3300 // C++ [dcl.fct.default]p5: 3301 // The names in the [default argument] expression are bound, and 3302 // the semantic constraints are checked, at the point where the 3303 // default argument expression appears. 3304 ContextRAII SavedContext(*this, FD); 3305 Result = SubstExpr(UninstExpr, ArgList); 3306 } 3307 if (Result.isInvalid()) 3308 return ExprError(); 3309 3310 // Check the expression as an initializer for the parameter. 3311 InitializedEntity Entity 3312 = InitializedEntity::InitializeParameter(Context, Param); 3313 InitializationKind Kind 3314 = InitializationKind::CreateCopy(Param->getLocation(), 3315 /*FIXME:EqualLoc*/UninstExpr->getSourceRange().getBegin()); 3316 Expr *ResultE = Result.takeAs<Expr>(); 3317 3318 InitializationSequence InitSeq(*this, Entity, Kind, &ResultE, 1); 3319 Result = InitSeq.Perform(*this, Entity, Kind, 3320 MultiExprArg(*this, &ResultE, 1)); 3321 if (Result.isInvalid()) 3322 return ExprError(); 3323 3324 // Build the default argument expression. 3325 return Owned(CXXDefaultArgExpr::Create(Context, CallLoc, Param, 3326 Result.takeAs<Expr>())); 3327 } 3328 3329 // If the default expression creates temporaries, we need to 3330 // push them to the current stack of expression temporaries so they'll 3331 // be properly destroyed. 3332 // FIXME: We should really be rebuilding the default argument with new 3333 // bound temporaries; see the comment in PR5810. 3334 // We don't need to do that with block decls, though, because 3335 // blocks in default argument expression can never capture anything. 3336 if (isa<ExprWithCleanups>(Param->getInit())) { 3337 // Set the "needs cleanups" bit regardless of whether there are 3338 // any explicit objects. 3339 ExprNeedsCleanups = true; 3340 3341 // Append all the objects to the cleanup list. Right now, this 3342 // should always be a no-op, because blocks in default argument 3343 // expressions should never be able to capture anything. 3344 assert(!cast<ExprWithCleanups>(Param->getInit())->getNumObjects() && 3345 "default argument expression has capturing blocks?"); 3346 } 3347 3348 // We already type-checked the argument, so we know it works. 3349 // Just mark all of the declarations in this potentially-evaluated expression 3350 // as being "referenced". 3351 MarkDeclarationsReferencedInExpr(Param->getDefaultArg()); 3352 return Owned(CXXDefaultArgExpr::Create(Context, CallLoc, Param)); 3353} 3354 3355/// ConvertArgumentsForCall - Converts the arguments specified in 3356/// Args/NumArgs to the parameter types of the function FDecl with 3357/// function prototype Proto. Call is the call expression itself, and 3358/// Fn is the function expression. For a C++ member function, this 3359/// routine does not attempt to convert the object argument. Returns 3360/// true if the call is ill-formed. 3361bool 3362Sema::ConvertArgumentsForCall(CallExpr *Call, Expr *Fn, 3363 FunctionDecl *FDecl, 3364 const FunctionProtoType *Proto, 3365 Expr **Args, unsigned NumArgs, 3366 SourceLocation RParenLoc, 3367 bool IsExecConfig) { 3368 // Bail out early if calling a builtin with custom typechecking. 3369 // We don't need to do this in the 3370 if (FDecl) 3371 if (unsigned ID = FDecl->getBuiltinID()) 3372 if (Context.BuiltinInfo.hasCustomTypechecking(ID)) 3373 return false; 3374 3375 // C99 6.5.2.2p7 - the arguments are implicitly converted, as if by 3376 // assignment, to the types of the corresponding parameter, ... 3377 unsigned NumArgsInProto = Proto->getNumArgs(); 3378 bool Invalid = false; 3379 unsigned MinArgs = FDecl ? FDecl->getMinRequiredArguments() : NumArgsInProto; 3380 unsigned FnKind = Fn->getType()->isBlockPointerType() 3381 ? 1 /* block */ 3382 : (IsExecConfig ? 3 /* kernel function (exec config) */ 3383 : 0 /* function */); 3384 3385 // If too few arguments are available (and we don't have default 3386 // arguments for the remaining parameters), don't make the call. 3387 if (NumArgs < NumArgsInProto) { 3388 if (NumArgs < MinArgs) { 3389 Diag(RParenLoc, MinArgs == NumArgsInProto 3390 ? diag::err_typecheck_call_too_few_args 3391 : diag::err_typecheck_call_too_few_args_at_least) 3392 << FnKind 3393 << MinArgs << NumArgs << Fn->getSourceRange(); 3394 3395 // Emit the location of the prototype. 3396 if (FDecl && !FDecl->getBuiltinID() && !IsExecConfig) 3397 Diag(FDecl->getLocStart(), diag::note_callee_decl) 3398 << FDecl; 3399 3400 return true; 3401 } 3402 Call->setNumArgs(Context, NumArgsInProto); 3403 } 3404 3405 // If too many are passed and not variadic, error on the extras and drop 3406 // them. 3407 if (NumArgs > NumArgsInProto) { 3408 if (!Proto->isVariadic()) { 3409 Diag(Args[NumArgsInProto]->getLocStart(), 3410 MinArgs == NumArgsInProto 3411 ? diag::err_typecheck_call_too_many_args 3412 : diag::err_typecheck_call_too_many_args_at_most) 3413 << FnKind 3414 << NumArgsInProto << NumArgs << Fn->getSourceRange() 3415 << SourceRange(Args[NumArgsInProto]->getLocStart(), 3416 Args[NumArgs-1]->getLocEnd()); 3417 3418 // Emit the location of the prototype. 3419 if (FDecl && !FDecl->getBuiltinID() && !IsExecConfig) 3420 Diag(FDecl->getLocStart(), diag::note_callee_decl) 3421 << FDecl; 3422 3423 // This deletes the extra arguments. 3424 Call->setNumArgs(Context, NumArgsInProto); 3425 return true; 3426 } 3427 } 3428 SmallVector<Expr *, 8> AllArgs; 3429 VariadicCallType CallType = 3430 Proto->isVariadic() ? VariadicFunction : VariadicDoesNotApply; 3431 if (Fn->getType()->isBlockPointerType()) 3432 CallType = VariadicBlock; // Block 3433 else if (isa<MemberExpr>(Fn)) 3434 CallType = VariadicMethod; 3435 Invalid = GatherArgumentsForCall(Call->getSourceRange().getBegin(), FDecl, 3436 Proto, 0, Args, NumArgs, AllArgs, CallType); 3437 if (Invalid) 3438 return true; 3439 unsigned TotalNumArgs = AllArgs.size(); 3440 for (unsigned i = 0; i < TotalNumArgs; ++i) 3441 Call->setArg(i, AllArgs[i]); 3442 3443 return false; 3444} 3445 3446bool Sema::GatherArgumentsForCall(SourceLocation CallLoc, 3447 FunctionDecl *FDecl, 3448 const FunctionProtoType *Proto, 3449 unsigned FirstProtoArg, 3450 Expr **Args, unsigned NumArgs, 3451 SmallVector<Expr *, 8> &AllArgs, 3452 VariadicCallType CallType) { 3453 unsigned NumArgsInProto = Proto->getNumArgs(); 3454 unsigned NumArgsToCheck = NumArgs; 3455 bool Invalid = false; 3456 if (NumArgs != NumArgsInProto) 3457 // Use default arguments for missing arguments 3458 NumArgsToCheck = NumArgsInProto; 3459 unsigned ArgIx = 0; 3460 // Continue to check argument types (even if we have too few/many args). 3461 for (unsigned i = FirstProtoArg; i != NumArgsToCheck; i++) { 3462 QualType ProtoArgType = Proto->getArgType(i); 3463 3464 Expr *Arg; 3465 ParmVarDecl *Param; 3466 if (ArgIx < NumArgs) { 3467 Arg = Args[ArgIx++]; 3468 3469 if (RequireCompleteType(Arg->getSourceRange().getBegin(), 3470 ProtoArgType, 3471 PDiag(diag::err_call_incomplete_argument) 3472 << Arg->getSourceRange())) 3473 return true; 3474 3475 // Pass the argument 3476 Param = 0; 3477 if (FDecl && i < FDecl->getNumParams()) 3478 Param = FDecl->getParamDecl(i); 3479 3480 // Strip the unbridged-cast placeholder expression off, if applicable. 3481 if (Arg->getType() == Context.ARCUnbridgedCastTy && 3482 FDecl && FDecl->hasAttr<CFAuditedTransferAttr>() && 3483 (!Param || !Param->hasAttr<CFConsumedAttr>())) 3484 Arg = stripARCUnbridgedCast(Arg); 3485 3486 InitializedEntity Entity = 3487 Param? InitializedEntity::InitializeParameter(Context, Param) 3488 : InitializedEntity::InitializeParameter(Context, ProtoArgType, 3489 Proto->isArgConsumed(i)); 3490 ExprResult ArgE = PerformCopyInitialization(Entity, 3491 SourceLocation(), 3492 Owned(Arg)); 3493 if (ArgE.isInvalid()) 3494 return true; 3495 3496 Arg = ArgE.takeAs<Expr>(); 3497 } else { 3498 Param = FDecl->getParamDecl(i); 3499 3500 ExprResult ArgExpr = 3501 BuildCXXDefaultArgExpr(CallLoc, FDecl, Param); 3502 if (ArgExpr.isInvalid()) 3503 return true; 3504 3505 Arg = ArgExpr.takeAs<Expr>(); 3506 } 3507 3508 // Check for array bounds violations for each argument to the call. This 3509 // check only triggers warnings when the argument isn't a more complex Expr 3510 // with its own checking, such as a BinaryOperator. 3511 CheckArrayAccess(Arg); 3512 3513 // Check for violations of C99 static array rules (C99 6.7.5.3p7). 3514 CheckStaticArrayArgument(CallLoc, Param, Arg); 3515 3516 AllArgs.push_back(Arg); 3517 } 3518 3519 // If this is a variadic call, handle args passed through "...". 3520 if (CallType != VariadicDoesNotApply) { 3521 3522 // Assume that extern "C" functions with variadic arguments that 3523 // return __unknown_anytype aren't *really* variadic. 3524 if (Proto->getResultType() == Context.UnknownAnyTy && 3525 FDecl && FDecl->isExternC()) { 3526 for (unsigned i = ArgIx; i != NumArgs; ++i) { 3527 ExprResult arg; 3528 if (isa<ExplicitCastExpr>(Args[i]->IgnoreParens())) 3529 arg = DefaultFunctionArrayLvalueConversion(Args[i]); 3530 else 3531 arg = DefaultVariadicArgumentPromotion(Args[i], CallType, FDecl); 3532 Invalid |= arg.isInvalid(); 3533 AllArgs.push_back(arg.take()); 3534 } 3535 3536 // Otherwise do argument promotion, (C99 6.5.2.2p7). 3537 } else { 3538 for (unsigned i = ArgIx; i != NumArgs; ++i) { 3539 ExprResult Arg = DefaultVariadicArgumentPromotion(Args[i], CallType, 3540 FDecl); 3541 Invalid |= Arg.isInvalid(); 3542 AllArgs.push_back(Arg.take()); 3543 } 3544 } 3545 3546 // Check for array bounds violations. 3547 for (unsigned i = ArgIx; i != NumArgs; ++i) 3548 CheckArrayAccess(Args[i]); 3549 } 3550 return Invalid; 3551} 3552 3553static void DiagnoseCalleeStaticArrayParam(Sema &S, ParmVarDecl *PVD) { 3554 TypeLoc TL = PVD->getTypeSourceInfo()->getTypeLoc(); 3555 if (ArrayTypeLoc *ATL = dyn_cast<ArrayTypeLoc>(&TL)) 3556 S.Diag(PVD->getLocation(), diag::note_callee_static_array) 3557 << ATL->getLocalSourceRange(); 3558} 3559 3560/// CheckStaticArrayArgument - If the given argument corresponds to a static 3561/// array parameter, check that it is non-null, and that if it is formed by 3562/// array-to-pointer decay, the underlying array is sufficiently large. 3563/// 3564/// C99 6.7.5.3p7: If the keyword static also appears within the [ and ] of the 3565/// array type derivation, then for each call to the function, the value of the 3566/// corresponding actual argument shall provide access to the first element of 3567/// an array with at least as many elements as specified by the size expression. 3568void 3569Sema::CheckStaticArrayArgument(SourceLocation CallLoc, 3570 ParmVarDecl *Param, 3571 const Expr *ArgExpr) { 3572 // Static array parameters are not supported in C++. 3573 if (!Param || getLangOptions().CPlusPlus) 3574 return; 3575 3576 QualType OrigTy = Param->getOriginalType(); 3577 3578 const ArrayType *AT = Context.getAsArrayType(OrigTy); 3579 if (!AT || AT->getSizeModifier() != ArrayType::Static) 3580 return; 3581 3582 if (ArgExpr->isNullPointerConstant(Context, 3583 Expr::NPC_NeverValueDependent)) { 3584 Diag(CallLoc, diag::warn_null_arg) << ArgExpr->getSourceRange(); 3585 DiagnoseCalleeStaticArrayParam(*this, Param); 3586 return; 3587 } 3588 3589 const ConstantArrayType *CAT = dyn_cast<ConstantArrayType>(AT); 3590 if (!CAT) 3591 return; 3592 3593 const ConstantArrayType *ArgCAT = 3594 Context.getAsConstantArrayType(ArgExpr->IgnoreParenImpCasts()->getType()); 3595 if (!ArgCAT) 3596 return; 3597 3598 if (ArgCAT->getSize().ult(CAT->getSize())) { 3599 Diag(CallLoc, diag::warn_static_array_too_small) 3600 << ArgExpr->getSourceRange() 3601 << (unsigned) ArgCAT->getSize().getZExtValue() 3602 << (unsigned) CAT->getSize().getZExtValue(); 3603 DiagnoseCalleeStaticArrayParam(*this, Param); 3604 } 3605} 3606 3607/// Given a function expression of unknown-any type, try to rebuild it 3608/// to have a function type. 3609static ExprResult rebuildUnknownAnyFunction(Sema &S, Expr *fn); 3610 3611/// ActOnCallExpr - Handle a call to Fn with the specified array of arguments. 3612/// This provides the location of the left/right parens and a list of comma 3613/// locations. 3614ExprResult 3615Sema::ActOnCallExpr(Scope *S, Expr *Fn, SourceLocation LParenLoc, 3616 MultiExprArg ArgExprs, SourceLocation RParenLoc, 3617 Expr *ExecConfig, bool IsExecConfig) { 3618 unsigned NumArgs = ArgExprs.size(); 3619 3620 // Since this might be a postfix expression, get rid of ParenListExprs. 3621 ExprResult Result = MaybeConvertParenListExprToParenExpr(S, Fn); 3622 if (Result.isInvalid()) return ExprError(); 3623 Fn = Result.take(); 3624 3625 Expr **Args = ArgExprs.release(); 3626 3627 if (getLangOptions().CPlusPlus) { 3628 // If this is a pseudo-destructor expression, build the call immediately. 3629 if (isa<CXXPseudoDestructorExpr>(Fn)) { 3630 if (NumArgs > 0) { 3631 // Pseudo-destructor calls should not have any arguments. 3632 Diag(Fn->getLocStart(), diag::err_pseudo_dtor_call_with_args) 3633 << FixItHint::CreateRemoval( 3634 SourceRange(Args[0]->getLocStart(), 3635 Args[NumArgs-1]->getLocEnd())); 3636 3637 NumArgs = 0; 3638 } 3639 3640 return Owned(new (Context) CallExpr(Context, Fn, 0, 0, Context.VoidTy, 3641 VK_RValue, RParenLoc)); 3642 } 3643 3644 // Determine whether this is a dependent call inside a C++ template, 3645 // in which case we won't do any semantic analysis now. 3646 // FIXME: Will need to cache the results of name lookup (including ADL) in 3647 // Fn. 3648 bool Dependent = false; 3649 if (Fn->isTypeDependent()) 3650 Dependent = true; 3651 else if (Expr::hasAnyTypeDependentArguments(Args, NumArgs)) 3652 Dependent = true; 3653 3654 if (Dependent) { 3655 if (ExecConfig) { 3656 return Owned(new (Context) CUDAKernelCallExpr( 3657 Context, Fn, cast<CallExpr>(ExecConfig), Args, NumArgs, 3658 Context.DependentTy, VK_RValue, RParenLoc)); 3659 } else { 3660 return Owned(new (Context) CallExpr(Context, Fn, Args, NumArgs, 3661 Context.DependentTy, VK_RValue, 3662 RParenLoc)); 3663 } 3664 } 3665 3666 // Determine whether this is a call to an object (C++ [over.call.object]). 3667 if (Fn->getType()->isRecordType()) 3668 return Owned(BuildCallToObjectOfClassType(S, Fn, LParenLoc, Args, NumArgs, 3669 RParenLoc)); 3670 3671 if (Fn->getType() == Context.UnknownAnyTy) { 3672 ExprResult result = rebuildUnknownAnyFunction(*this, Fn); 3673 if (result.isInvalid()) return ExprError(); 3674 Fn = result.take(); 3675 } 3676 3677 if (Fn->getType() == Context.BoundMemberTy) { 3678 return BuildCallToMemberFunction(S, Fn, LParenLoc, Args, NumArgs, 3679 RParenLoc); 3680 } 3681 } 3682 3683 // Check for overloaded calls. This can happen even in C due to extensions. 3684 if (Fn->getType() == Context.OverloadTy) { 3685 OverloadExpr::FindResult find = OverloadExpr::find(Fn); 3686 3687 // We aren't supposed to apply this logic for if there's an '&' involved. 3688 if (!find.HasFormOfMemberPointer) { 3689 OverloadExpr *ovl = find.Expression; 3690 if (isa<UnresolvedLookupExpr>(ovl)) { 3691 UnresolvedLookupExpr *ULE = cast<UnresolvedLookupExpr>(ovl); 3692 return BuildOverloadedCallExpr(S, Fn, ULE, LParenLoc, Args, NumArgs, 3693 RParenLoc, ExecConfig); 3694 } else { 3695 return BuildCallToMemberFunction(S, Fn, LParenLoc, Args, NumArgs, 3696 RParenLoc); 3697 } 3698 } 3699 } 3700 3701 // If we're directly calling a function, get the appropriate declaration. 3702 if (Fn->getType() == Context.UnknownAnyTy) { 3703 ExprResult result = rebuildUnknownAnyFunction(*this, Fn); 3704 if (result.isInvalid()) return ExprError(); 3705 Fn = result.take(); 3706 } 3707 3708 Expr *NakedFn = Fn->IgnoreParens(); 3709 3710 NamedDecl *NDecl = 0; 3711 if (UnaryOperator *UnOp = dyn_cast<UnaryOperator>(NakedFn)) 3712 if (UnOp->getOpcode() == UO_AddrOf) 3713 NakedFn = UnOp->getSubExpr()->IgnoreParens(); 3714 3715 if (isa<DeclRefExpr>(NakedFn)) 3716 NDecl = cast<DeclRefExpr>(NakedFn)->getDecl(); 3717 else if (isa<MemberExpr>(NakedFn)) 3718 NDecl = cast<MemberExpr>(NakedFn)->getMemberDecl(); 3719 3720 return BuildResolvedCallExpr(Fn, NDecl, LParenLoc, Args, NumArgs, RParenLoc, 3721 ExecConfig, IsExecConfig); 3722} 3723 3724ExprResult 3725Sema::ActOnCUDAExecConfigExpr(Scope *S, SourceLocation LLLLoc, 3726 MultiExprArg ExecConfig, SourceLocation GGGLoc) { 3727 FunctionDecl *ConfigDecl = Context.getcudaConfigureCallDecl(); 3728 if (!ConfigDecl) 3729 return ExprError(Diag(LLLLoc, diag::err_undeclared_var_use) 3730 << "cudaConfigureCall"); 3731 QualType ConfigQTy = ConfigDecl->getType(); 3732 3733 DeclRefExpr *ConfigDR = new (Context) DeclRefExpr( 3734 ConfigDecl, ConfigQTy, VK_LValue, LLLLoc); 3735 3736 return ActOnCallExpr(S, ConfigDR, LLLLoc, ExecConfig, GGGLoc, 0, 3737 /*IsExecConfig=*/true); 3738} 3739 3740/// ActOnAsTypeExpr - create a new asType (bitcast) from the arguments. 3741/// 3742/// __builtin_astype( value, dst type ) 3743/// 3744ExprResult Sema::ActOnAsTypeExpr(Expr *E, ParsedType ParsedDestTy, 3745 SourceLocation BuiltinLoc, 3746 SourceLocation RParenLoc) { 3747 ExprValueKind VK = VK_RValue; 3748 ExprObjectKind OK = OK_Ordinary; 3749 QualType DstTy = GetTypeFromParser(ParsedDestTy); 3750 QualType SrcTy = E->getType(); 3751 if (Context.getTypeSize(DstTy) != Context.getTypeSize(SrcTy)) 3752 return ExprError(Diag(BuiltinLoc, 3753 diag::err_invalid_astype_of_different_size) 3754 << DstTy 3755 << SrcTy 3756 << E->getSourceRange()); 3757 return Owned(new (Context) AsTypeExpr(E, DstTy, VK, OK, BuiltinLoc, 3758 RParenLoc)); 3759} 3760 3761/// BuildResolvedCallExpr - Build a call to a resolved expression, 3762/// i.e. an expression not of \p OverloadTy. The expression should 3763/// unary-convert to an expression of function-pointer or 3764/// block-pointer type. 3765/// 3766/// \param NDecl the declaration being called, if available 3767ExprResult 3768Sema::BuildResolvedCallExpr(Expr *Fn, NamedDecl *NDecl, 3769 SourceLocation LParenLoc, 3770 Expr **Args, unsigned NumArgs, 3771 SourceLocation RParenLoc, 3772 Expr *Config, bool IsExecConfig) { 3773 FunctionDecl *FDecl = dyn_cast_or_null<FunctionDecl>(NDecl); 3774 3775 // Promote the function operand. 3776 ExprResult Result = UsualUnaryConversions(Fn); 3777 if (Result.isInvalid()) 3778 return ExprError(); 3779 Fn = Result.take(); 3780 3781 // Make the call expr early, before semantic checks. This guarantees cleanup 3782 // of arguments and function on error. 3783 CallExpr *TheCall; 3784 if (Config) { 3785 TheCall = new (Context) CUDAKernelCallExpr(Context, Fn, 3786 cast<CallExpr>(Config), 3787 Args, NumArgs, 3788 Context.BoolTy, 3789 VK_RValue, 3790 RParenLoc); 3791 } else { 3792 TheCall = new (Context) CallExpr(Context, Fn, 3793 Args, NumArgs, 3794 Context.BoolTy, 3795 VK_RValue, 3796 RParenLoc); 3797 } 3798 3799 unsigned BuiltinID = (FDecl ? FDecl->getBuiltinID() : 0); 3800 3801 // Bail out early if calling a builtin with custom typechecking. 3802 if (BuiltinID && Context.BuiltinInfo.hasCustomTypechecking(BuiltinID)) 3803 return CheckBuiltinFunctionCall(BuiltinID, TheCall); 3804 3805 retry: 3806 const FunctionType *FuncT; 3807 if (const PointerType *PT = Fn->getType()->getAs<PointerType>()) { 3808 // C99 6.5.2.2p1 - "The expression that denotes the called function shall 3809 // have type pointer to function". 3810 FuncT = PT->getPointeeType()->getAs<FunctionType>(); 3811 if (FuncT == 0) 3812 return ExprError(Diag(LParenLoc, diag::err_typecheck_call_not_function) 3813 << Fn->getType() << Fn->getSourceRange()); 3814 } else if (const BlockPointerType *BPT = 3815 Fn->getType()->getAs<BlockPointerType>()) { 3816 FuncT = BPT->getPointeeType()->castAs<FunctionType>(); 3817 } else { 3818 // Handle calls to expressions of unknown-any type. 3819 if (Fn->getType() == Context.UnknownAnyTy) { 3820 ExprResult rewrite = rebuildUnknownAnyFunction(*this, Fn); 3821 if (rewrite.isInvalid()) return ExprError(); 3822 Fn = rewrite.take(); 3823 TheCall->setCallee(Fn); 3824 goto retry; 3825 } 3826 3827 return ExprError(Diag(LParenLoc, diag::err_typecheck_call_not_function) 3828 << Fn->getType() << Fn->getSourceRange()); 3829 } 3830 3831 if (getLangOptions().CUDA) { 3832 if (Config) { 3833 // CUDA: Kernel calls must be to global functions 3834 if (FDecl && !FDecl->hasAttr<CUDAGlobalAttr>()) 3835 return ExprError(Diag(LParenLoc,diag::err_kern_call_not_global_function) 3836 << FDecl->getName() << Fn->getSourceRange()); 3837 3838 // CUDA: Kernel function must have 'void' return type 3839 if (!FuncT->getResultType()->isVoidType()) 3840 return ExprError(Diag(LParenLoc, diag::err_kern_type_not_void_return) 3841 << Fn->getType() << Fn->getSourceRange()); 3842 } else { 3843 // CUDA: Calls to global functions must be configured 3844 if (FDecl && FDecl->hasAttr<CUDAGlobalAttr>()) 3845 return ExprError(Diag(LParenLoc, diag::err_global_call_not_config) 3846 << FDecl->getName() << Fn->getSourceRange()); 3847 } 3848 } 3849 3850 // Check for a valid return type 3851 if (CheckCallReturnType(FuncT->getResultType(), 3852 Fn->getSourceRange().getBegin(), TheCall, 3853 FDecl)) 3854 return ExprError(); 3855 3856 // We know the result type of the call, set it. 3857 TheCall->setType(FuncT->getCallResultType(Context)); 3858 TheCall->setValueKind(Expr::getValueKindForType(FuncT->getResultType())); 3859 3860 if (const FunctionProtoType *Proto = dyn_cast<FunctionProtoType>(FuncT)) { 3861 if (ConvertArgumentsForCall(TheCall, Fn, FDecl, Proto, Args, NumArgs, 3862 RParenLoc, IsExecConfig)) 3863 return ExprError(); 3864 } else { 3865 assert(isa<FunctionNoProtoType>(FuncT) && "Unknown FunctionType!"); 3866 3867 if (FDecl) { 3868 // Check if we have too few/too many template arguments, based 3869 // on our knowledge of the function definition. 3870 const FunctionDecl *Def = 0; 3871 if (FDecl->hasBody(Def) && NumArgs != Def->param_size()) { 3872 const FunctionProtoType *Proto 3873 = Def->getType()->getAs<FunctionProtoType>(); 3874 if (!Proto || !(Proto->isVariadic() && NumArgs >= Def->param_size())) 3875 Diag(RParenLoc, diag::warn_call_wrong_number_of_arguments) 3876 << (NumArgs > Def->param_size()) << FDecl << Fn->getSourceRange(); 3877 } 3878 3879 // If the function we're calling isn't a function prototype, but we have 3880 // a function prototype from a prior declaratiom, use that prototype. 3881 if (!FDecl->hasPrototype()) 3882 Proto = FDecl->getType()->getAs<FunctionProtoType>(); 3883 } 3884 3885 // Promote the arguments (C99 6.5.2.2p6). 3886 for (unsigned i = 0; i != NumArgs; i++) { 3887 Expr *Arg = Args[i]; 3888 3889 if (Proto && i < Proto->getNumArgs()) { 3890 InitializedEntity Entity 3891 = InitializedEntity::InitializeParameter(Context, 3892 Proto->getArgType(i), 3893 Proto->isArgConsumed(i)); 3894 ExprResult ArgE = PerformCopyInitialization(Entity, 3895 SourceLocation(), 3896 Owned(Arg)); 3897 if (ArgE.isInvalid()) 3898 return true; 3899 3900 Arg = ArgE.takeAs<Expr>(); 3901 3902 } else { 3903 ExprResult ArgE = DefaultArgumentPromotion(Arg); 3904 3905 if (ArgE.isInvalid()) 3906 return true; 3907 3908 Arg = ArgE.takeAs<Expr>(); 3909 } 3910 3911 if (RequireCompleteType(Arg->getSourceRange().getBegin(), 3912 Arg->getType(), 3913 PDiag(diag::err_call_incomplete_argument) 3914 << Arg->getSourceRange())) 3915 return ExprError(); 3916 3917 TheCall->setArg(i, Arg); 3918 } 3919 } 3920 3921 if (CXXMethodDecl *Method = dyn_cast_or_null<CXXMethodDecl>(FDecl)) 3922 if (!Method->isStatic()) 3923 return ExprError(Diag(LParenLoc, diag::err_member_call_without_object) 3924 << Fn->getSourceRange()); 3925 3926 // Check for sentinels 3927 if (NDecl) 3928 DiagnoseSentinelCalls(NDecl, LParenLoc, Args, NumArgs); 3929 3930 // Do special checking on direct calls to functions. 3931 if (FDecl) { 3932 if (CheckFunctionCall(FDecl, TheCall)) 3933 return ExprError(); 3934 3935 if (BuiltinID) 3936 return CheckBuiltinFunctionCall(BuiltinID, TheCall); 3937 } else if (NDecl) { 3938 if (CheckBlockCall(NDecl, TheCall)) 3939 return ExprError(); 3940 } 3941 3942 return MaybeBindToTemporary(TheCall); 3943} 3944 3945ExprResult 3946Sema::ActOnCompoundLiteral(SourceLocation LParenLoc, ParsedType Ty, 3947 SourceLocation RParenLoc, Expr *InitExpr) { 3948 assert((Ty != 0) && "ActOnCompoundLiteral(): missing type"); 3949 // FIXME: put back this assert when initializers are worked out. 3950 //assert((InitExpr != 0) && "ActOnCompoundLiteral(): missing expression"); 3951 3952 TypeSourceInfo *TInfo; 3953 QualType literalType = GetTypeFromParser(Ty, &TInfo); 3954 if (!TInfo) 3955 TInfo = Context.getTrivialTypeSourceInfo(literalType); 3956 3957 return BuildCompoundLiteralExpr(LParenLoc, TInfo, RParenLoc, InitExpr); 3958} 3959 3960ExprResult 3961Sema::BuildCompoundLiteralExpr(SourceLocation LParenLoc, TypeSourceInfo *TInfo, 3962 SourceLocation RParenLoc, Expr *LiteralExpr) { 3963 QualType literalType = TInfo->getType(); 3964 3965 if (literalType->isArrayType()) { 3966 if (RequireCompleteType(LParenLoc, Context.getBaseElementType(literalType), 3967 PDiag(diag::err_illegal_decl_array_incomplete_type) 3968 << SourceRange(LParenLoc, 3969 LiteralExpr->getSourceRange().getEnd()))) 3970 return ExprError(); 3971 if (literalType->isVariableArrayType()) 3972 return ExprError(Diag(LParenLoc, diag::err_variable_object_no_init) 3973 << SourceRange(LParenLoc, LiteralExpr->getSourceRange().getEnd())); 3974 } else if (!literalType->isDependentType() && 3975 RequireCompleteType(LParenLoc, literalType, 3976 PDiag(diag::err_typecheck_decl_incomplete_type) 3977 << SourceRange(LParenLoc, 3978 LiteralExpr->getSourceRange().getEnd()))) 3979 return ExprError(); 3980 3981 InitializedEntity Entity 3982 = InitializedEntity::InitializeTemporary(literalType); 3983 InitializationKind Kind 3984 = InitializationKind::CreateCStyleCast(LParenLoc, 3985 SourceRange(LParenLoc, RParenLoc)); 3986 InitializationSequence InitSeq(*this, Entity, Kind, &LiteralExpr, 1); 3987 ExprResult Result = InitSeq.Perform(*this, Entity, Kind, 3988 MultiExprArg(*this, &LiteralExpr, 1), 3989 &literalType); 3990 if (Result.isInvalid()) 3991 return ExprError(); 3992 LiteralExpr = Result.get(); 3993 3994 bool isFileScope = getCurFunctionOrMethodDecl() == 0; 3995 if (isFileScope) { // 6.5.2.5p3 3996 if (CheckForConstantInitializer(LiteralExpr, literalType)) 3997 return ExprError(); 3998 } 3999 4000 // In C, compound literals are l-values for some reason. 4001 ExprValueKind VK = getLangOptions().CPlusPlus ? VK_RValue : VK_LValue; 4002 4003 return MaybeBindToTemporary( 4004 new (Context) CompoundLiteralExpr(LParenLoc, TInfo, literalType, 4005 VK, LiteralExpr, isFileScope)); 4006} 4007 4008ExprResult 4009Sema::ActOnInitList(SourceLocation LBraceLoc, MultiExprArg InitArgList, 4010 SourceLocation RBraceLoc) { 4011 unsigned NumInit = InitArgList.size(); 4012 Expr **InitList = InitArgList.release(); 4013 4014 // Immediately handle non-overload placeholders. Overloads can be 4015 // resolved contextually, but everything else here can't. 4016 for (unsigned I = 0; I != NumInit; ++I) { 4017 if (InitList[I]->getType()->isNonOverloadPlaceholderType()) { 4018 ExprResult result = CheckPlaceholderExpr(InitList[I]); 4019 4020 // Ignore failures; dropping the entire initializer list because 4021 // of one failure would be terrible for indexing/etc. 4022 if (result.isInvalid()) continue; 4023 4024 InitList[I] = result.take(); 4025 } 4026 } 4027 4028 // Semantic analysis for initializers is done by ActOnDeclarator() and 4029 // CheckInitializer() - it requires knowledge of the object being intialized. 4030 4031 InitListExpr *E = new (Context) InitListExpr(Context, LBraceLoc, InitList, 4032 NumInit, RBraceLoc); 4033 E->setType(Context.VoidTy); // FIXME: just a place holder for now. 4034 return Owned(E); 4035} 4036 4037/// Do an explicit extend of the given block pointer if we're in ARC. 4038static void maybeExtendBlockObject(Sema &S, ExprResult &E) { 4039 assert(E.get()->getType()->isBlockPointerType()); 4040 assert(E.get()->isRValue()); 4041 4042 // Only do this in an r-value context. 4043 if (!S.getLangOptions().ObjCAutoRefCount) return; 4044 4045 E = ImplicitCastExpr::Create(S.Context, E.get()->getType(), 4046 CK_ARCExtendBlockObject, E.get(), 4047 /*base path*/ 0, VK_RValue); 4048 S.ExprNeedsCleanups = true; 4049} 4050 4051/// Prepare a conversion of the given expression to an ObjC object 4052/// pointer type. 4053CastKind Sema::PrepareCastToObjCObjectPointer(ExprResult &E) { 4054 QualType type = E.get()->getType(); 4055 if (type->isObjCObjectPointerType()) { 4056 return CK_BitCast; 4057 } else if (type->isBlockPointerType()) { 4058 maybeExtendBlockObject(*this, E); 4059 return CK_BlockPointerToObjCPointerCast; 4060 } else { 4061 assert(type->isPointerType()); 4062 return CK_CPointerToObjCPointerCast; 4063 } 4064} 4065 4066/// Prepares for a scalar cast, performing all the necessary stages 4067/// except the final cast and returning the kind required. 4068CastKind Sema::PrepareScalarCast(ExprResult &Src, QualType DestTy) { 4069 // Both Src and Dest are scalar types, i.e. arithmetic or pointer. 4070 // Also, callers should have filtered out the invalid cases with 4071 // pointers. Everything else should be possible. 4072 4073 QualType SrcTy = Src.get()->getType(); 4074 if (Context.hasSameUnqualifiedType(SrcTy, DestTy)) 4075 return CK_NoOp; 4076 4077 switch (Type::ScalarTypeKind SrcKind = SrcTy->getScalarTypeKind()) { 4078 case Type::STK_MemberPointer: 4079 llvm_unreachable("member pointer type in C"); 4080 4081 case Type::STK_CPointer: 4082 case Type::STK_BlockPointer: 4083 case Type::STK_ObjCObjectPointer: 4084 switch (DestTy->getScalarTypeKind()) { 4085 case Type::STK_CPointer: 4086 return CK_BitCast; 4087 case Type::STK_BlockPointer: 4088 return (SrcKind == Type::STK_BlockPointer 4089 ? CK_BitCast : CK_AnyPointerToBlockPointerCast); 4090 case Type::STK_ObjCObjectPointer: 4091 if (SrcKind == Type::STK_ObjCObjectPointer) 4092 return CK_BitCast; 4093 else if (SrcKind == Type::STK_CPointer) 4094 return CK_CPointerToObjCPointerCast; 4095 else { 4096 maybeExtendBlockObject(*this, Src); 4097 return CK_BlockPointerToObjCPointerCast; 4098 } 4099 case Type::STK_Bool: 4100 return CK_PointerToBoolean; 4101 case Type::STK_Integral: 4102 return CK_PointerToIntegral; 4103 case Type::STK_Floating: 4104 case Type::STK_FloatingComplex: 4105 case Type::STK_IntegralComplex: 4106 case Type::STK_MemberPointer: 4107 llvm_unreachable("illegal cast from pointer"); 4108 } 4109 break; 4110 4111 case Type::STK_Bool: // casting from bool is like casting from an integer 4112 case Type::STK_Integral: 4113 switch (DestTy->getScalarTypeKind()) { 4114 case Type::STK_CPointer: 4115 case Type::STK_ObjCObjectPointer: 4116 case Type::STK_BlockPointer: 4117 if (Src.get()->isNullPointerConstant(Context, 4118 Expr::NPC_ValueDependentIsNull)) 4119 return CK_NullToPointer; 4120 return CK_IntegralToPointer; 4121 case Type::STK_Bool: 4122 return CK_IntegralToBoolean; 4123 case Type::STK_Integral: 4124 return CK_IntegralCast; 4125 case Type::STK_Floating: 4126 return CK_IntegralToFloating; 4127 case Type::STK_IntegralComplex: 4128 Src = ImpCastExprToType(Src.take(), 4129 DestTy->castAs<ComplexType>()->getElementType(), 4130 CK_IntegralCast); 4131 return CK_IntegralRealToComplex; 4132 case Type::STK_FloatingComplex: 4133 Src = ImpCastExprToType(Src.take(), 4134 DestTy->castAs<ComplexType>()->getElementType(), 4135 CK_IntegralToFloating); 4136 return CK_FloatingRealToComplex; 4137 case Type::STK_MemberPointer: 4138 llvm_unreachable("member pointer type in C"); 4139 } 4140 break; 4141 4142 case Type::STK_Floating: 4143 switch (DestTy->getScalarTypeKind()) { 4144 case Type::STK_Floating: 4145 return CK_FloatingCast; 4146 case Type::STK_Bool: 4147 return CK_FloatingToBoolean; 4148 case Type::STK_Integral: 4149 return CK_FloatingToIntegral; 4150 case Type::STK_FloatingComplex: 4151 Src = ImpCastExprToType(Src.take(), 4152 DestTy->castAs<ComplexType>()->getElementType(), 4153 CK_FloatingCast); 4154 return CK_FloatingRealToComplex; 4155 case Type::STK_IntegralComplex: 4156 Src = ImpCastExprToType(Src.take(), 4157 DestTy->castAs<ComplexType>()->getElementType(), 4158 CK_FloatingToIntegral); 4159 return CK_IntegralRealToComplex; 4160 case Type::STK_CPointer: 4161 case Type::STK_ObjCObjectPointer: 4162 case Type::STK_BlockPointer: 4163 llvm_unreachable("valid float->pointer cast?"); 4164 case Type::STK_MemberPointer: 4165 llvm_unreachable("member pointer type in C"); 4166 } 4167 break; 4168 4169 case Type::STK_FloatingComplex: 4170 switch (DestTy->getScalarTypeKind()) { 4171 case Type::STK_FloatingComplex: 4172 return CK_FloatingComplexCast; 4173 case Type::STK_IntegralComplex: 4174 return CK_FloatingComplexToIntegralComplex; 4175 case Type::STK_Floating: { 4176 QualType ET = SrcTy->castAs<ComplexType>()->getElementType(); 4177 if (Context.hasSameType(ET, DestTy)) 4178 return CK_FloatingComplexToReal; 4179 Src = ImpCastExprToType(Src.take(), ET, CK_FloatingComplexToReal); 4180 return CK_FloatingCast; 4181 } 4182 case Type::STK_Bool: 4183 return CK_FloatingComplexToBoolean; 4184 case Type::STK_Integral: 4185 Src = ImpCastExprToType(Src.take(), 4186 SrcTy->castAs<ComplexType>()->getElementType(), 4187 CK_FloatingComplexToReal); 4188 return CK_FloatingToIntegral; 4189 case Type::STK_CPointer: 4190 case Type::STK_ObjCObjectPointer: 4191 case Type::STK_BlockPointer: 4192 llvm_unreachable("valid complex float->pointer cast?"); 4193 case Type::STK_MemberPointer: 4194 llvm_unreachable("member pointer type in C"); 4195 } 4196 break; 4197 4198 case Type::STK_IntegralComplex: 4199 switch (DestTy->getScalarTypeKind()) { 4200 case Type::STK_FloatingComplex: 4201 return CK_IntegralComplexToFloatingComplex; 4202 case Type::STK_IntegralComplex: 4203 return CK_IntegralComplexCast; 4204 case Type::STK_Integral: { 4205 QualType ET = SrcTy->castAs<ComplexType>()->getElementType(); 4206 if (Context.hasSameType(ET, DestTy)) 4207 return CK_IntegralComplexToReal; 4208 Src = ImpCastExprToType(Src.take(), ET, CK_IntegralComplexToReal); 4209 return CK_IntegralCast; 4210 } 4211 case Type::STK_Bool: 4212 return CK_IntegralComplexToBoolean; 4213 case Type::STK_Floating: 4214 Src = ImpCastExprToType(Src.take(), 4215 SrcTy->castAs<ComplexType>()->getElementType(), 4216 CK_IntegralComplexToReal); 4217 return CK_IntegralToFloating; 4218 case Type::STK_CPointer: 4219 case Type::STK_ObjCObjectPointer: 4220 case Type::STK_BlockPointer: 4221 llvm_unreachable("valid complex int->pointer cast?"); 4222 case Type::STK_MemberPointer: 4223 llvm_unreachable("member pointer type in C"); 4224 } 4225 break; 4226 } 4227 4228 llvm_unreachable("Unhandled scalar cast"); 4229} 4230 4231bool Sema::CheckVectorCast(SourceRange R, QualType VectorTy, QualType Ty, 4232 CastKind &Kind) { 4233 assert(VectorTy->isVectorType() && "Not a vector type!"); 4234 4235 if (Ty->isVectorType() || Ty->isIntegerType()) { 4236 if (Context.getTypeSize(VectorTy) != Context.getTypeSize(Ty)) 4237 return Diag(R.getBegin(), 4238 Ty->isVectorType() ? 4239 diag::err_invalid_conversion_between_vectors : 4240 diag::err_invalid_conversion_between_vector_and_integer) 4241 << VectorTy << Ty << R; 4242 } else 4243 return Diag(R.getBegin(), 4244 diag::err_invalid_conversion_between_vector_and_scalar) 4245 << VectorTy << Ty << R; 4246 4247 Kind = CK_BitCast; 4248 return false; 4249} 4250 4251ExprResult Sema::CheckExtVectorCast(SourceRange R, QualType DestTy, 4252 Expr *CastExpr, CastKind &Kind) { 4253 assert(DestTy->isExtVectorType() && "Not an extended vector type!"); 4254 4255 QualType SrcTy = CastExpr->getType(); 4256 4257 // If SrcTy is a VectorType, the total size must match to explicitly cast to 4258 // an ExtVectorType. 4259 // In OpenCL, casts between vectors of different types are not allowed. 4260 // (See OpenCL 6.2). 4261 if (SrcTy->isVectorType()) { 4262 if (Context.getTypeSize(DestTy) != Context.getTypeSize(SrcTy) 4263 || (getLangOptions().OpenCL && 4264 (DestTy.getCanonicalType() != SrcTy.getCanonicalType()))) { 4265 Diag(R.getBegin(),diag::err_invalid_conversion_between_ext_vectors) 4266 << DestTy << SrcTy << R; 4267 return ExprError(); 4268 } 4269 Kind = CK_BitCast; 4270 return Owned(CastExpr); 4271 } 4272 4273 // All non-pointer scalars can be cast to ExtVector type. The appropriate 4274 // conversion will take place first from scalar to elt type, and then 4275 // splat from elt type to vector. 4276 if (SrcTy->isPointerType()) 4277 return Diag(R.getBegin(), 4278 diag::err_invalid_conversion_between_vector_and_scalar) 4279 << DestTy << SrcTy << R; 4280 4281 QualType DestElemTy = DestTy->getAs<ExtVectorType>()->getElementType(); 4282 ExprResult CastExprRes = Owned(CastExpr); 4283 CastKind CK = PrepareScalarCast(CastExprRes, DestElemTy); 4284 if (CastExprRes.isInvalid()) 4285 return ExprError(); 4286 CastExpr = ImpCastExprToType(CastExprRes.take(), DestElemTy, CK).take(); 4287 4288 Kind = CK_VectorSplat; 4289 return Owned(CastExpr); 4290} 4291 4292ExprResult 4293Sema::ActOnCastExpr(Scope *S, SourceLocation LParenLoc, 4294 Declarator &D, ParsedType &Ty, 4295 SourceLocation RParenLoc, Expr *CastExpr) { 4296 assert(!D.isInvalidType() && (CastExpr != 0) && 4297 "ActOnCastExpr(): missing type or expr"); 4298 4299 TypeSourceInfo *castTInfo = GetTypeForDeclaratorCast(D, CastExpr->getType()); 4300 if (D.isInvalidType()) 4301 return ExprError(); 4302 4303 if (getLangOptions().CPlusPlus) { 4304 // Check that there are no default arguments (C++ only). 4305 CheckExtraCXXDefaultArguments(D); 4306 } 4307 4308 checkUnusedDeclAttributes(D); 4309 4310 QualType castType = castTInfo->getType(); 4311 Ty = CreateParsedType(castType, castTInfo); 4312 4313 bool isVectorLiteral = false; 4314 4315 // Check for an altivec or OpenCL literal, 4316 // i.e. all the elements are integer constants. 4317 ParenExpr *PE = dyn_cast<ParenExpr>(CastExpr); 4318 ParenListExpr *PLE = dyn_cast<ParenListExpr>(CastExpr); 4319 if ((getLangOptions().AltiVec || getLangOptions().OpenCL) 4320 && castType->isVectorType() && (PE || PLE)) { 4321 if (PLE && PLE->getNumExprs() == 0) { 4322 Diag(PLE->getExprLoc(), diag::err_altivec_empty_initializer); 4323 return ExprError(); 4324 } 4325 if (PE || PLE->getNumExprs() == 1) { 4326 Expr *E = (PE ? PE->getSubExpr() : PLE->getExpr(0)); 4327 if (!E->getType()->isVectorType()) 4328 isVectorLiteral = true; 4329 } 4330 else 4331 isVectorLiteral = true; 4332 } 4333 4334 // If this is a vector initializer, '(' type ')' '(' init, ..., init ')' 4335 // then handle it as such. 4336 if (isVectorLiteral) 4337 return BuildVectorLiteral(LParenLoc, RParenLoc, CastExpr, castTInfo); 4338 4339 // If the Expr being casted is a ParenListExpr, handle it specially. 4340 // This is not an AltiVec-style cast, so turn the ParenListExpr into a 4341 // sequence of BinOp comma operators. 4342 if (isa<ParenListExpr>(CastExpr)) { 4343 ExprResult Result = MaybeConvertParenListExprToParenExpr(S, CastExpr); 4344 if (Result.isInvalid()) return ExprError(); 4345 CastExpr = Result.take(); 4346 } 4347 4348 return BuildCStyleCastExpr(LParenLoc, castTInfo, RParenLoc, CastExpr); 4349} 4350 4351ExprResult Sema::BuildVectorLiteral(SourceLocation LParenLoc, 4352 SourceLocation RParenLoc, Expr *E, 4353 TypeSourceInfo *TInfo) { 4354 assert((isa<ParenListExpr>(E) || isa<ParenExpr>(E)) && 4355 "Expected paren or paren list expression"); 4356 4357 Expr **exprs; 4358 unsigned numExprs; 4359 Expr *subExpr; 4360 if (ParenListExpr *PE = dyn_cast<ParenListExpr>(E)) { 4361 exprs = PE->getExprs(); 4362 numExprs = PE->getNumExprs(); 4363 } else { 4364 subExpr = cast<ParenExpr>(E)->getSubExpr(); 4365 exprs = &subExpr; 4366 numExprs = 1; 4367 } 4368 4369 QualType Ty = TInfo->getType(); 4370 assert(Ty->isVectorType() && "Expected vector type"); 4371 4372 SmallVector<Expr *, 8> initExprs; 4373 const VectorType *VTy = Ty->getAs<VectorType>(); 4374 unsigned numElems = Ty->getAs<VectorType>()->getNumElements(); 4375 4376 // '(...)' form of vector initialization in AltiVec: the number of 4377 // initializers must be one or must match the size of the vector. 4378 // If a single value is specified in the initializer then it will be 4379 // replicated to all the components of the vector 4380 if (VTy->getVectorKind() == VectorType::AltiVecVector) { 4381 // The number of initializers must be one or must match the size of the 4382 // vector. If a single value is specified in the initializer then it will 4383 // be replicated to all the components of the vector 4384 if (numExprs == 1) { 4385 QualType ElemTy = Ty->getAs<VectorType>()->getElementType(); 4386 ExprResult Literal = DefaultLvalueConversion(exprs[0]); 4387 if (Literal.isInvalid()) 4388 return ExprError(); 4389 Literal = ImpCastExprToType(Literal.take(), ElemTy, 4390 PrepareScalarCast(Literal, ElemTy)); 4391 return BuildCStyleCastExpr(LParenLoc, TInfo, RParenLoc, Literal.take()); 4392 } 4393 else if (numExprs < numElems) { 4394 Diag(E->getExprLoc(), 4395 diag::err_incorrect_number_of_vector_initializers); 4396 return ExprError(); 4397 } 4398 else 4399 for (unsigned i = 0, e = numExprs; i != e; ++i) 4400 initExprs.push_back(exprs[i]); 4401 } 4402 else { 4403 // For OpenCL, when the number of initializers is a single value, 4404 // it will be replicated to all components of the vector. 4405 if (getLangOptions().OpenCL && 4406 VTy->getVectorKind() == VectorType::GenericVector && 4407 numExprs == 1) { 4408 QualType ElemTy = Ty->getAs<VectorType>()->getElementType(); 4409 ExprResult Literal = DefaultLvalueConversion(exprs[0]); 4410 if (Literal.isInvalid()) 4411 return ExprError(); 4412 Literal = ImpCastExprToType(Literal.take(), ElemTy, 4413 PrepareScalarCast(Literal, ElemTy)); 4414 return BuildCStyleCastExpr(LParenLoc, TInfo, RParenLoc, Literal.take()); 4415 } 4416 4417 for (unsigned i = 0, e = numExprs; i != e; ++i) 4418 initExprs.push_back(exprs[i]); 4419 } 4420 // FIXME: This means that pretty-printing the final AST will produce curly 4421 // braces instead of the original commas. 4422 InitListExpr *initE = new (Context) InitListExpr(Context, LParenLoc, 4423 &initExprs[0], 4424 initExprs.size(), RParenLoc); 4425 initE->setType(Ty); 4426 return BuildCompoundLiteralExpr(LParenLoc, TInfo, RParenLoc, initE); 4427} 4428 4429/// This is not an AltiVec-style cast, so turn the ParenListExpr into a sequence 4430/// of comma binary operators. 4431ExprResult 4432Sema::MaybeConvertParenListExprToParenExpr(Scope *S, Expr *OrigExpr) { 4433 ParenListExpr *E = dyn_cast<ParenListExpr>(OrigExpr); 4434 if (!E) 4435 return Owned(OrigExpr); 4436 4437 ExprResult Result(E->getExpr(0)); 4438 4439 for (unsigned i = 1, e = E->getNumExprs(); i != e && !Result.isInvalid(); ++i) 4440 Result = ActOnBinOp(S, E->getExprLoc(), tok::comma, Result.get(), 4441 E->getExpr(i)); 4442 4443 if (Result.isInvalid()) return ExprError(); 4444 4445 return ActOnParenExpr(E->getLParenLoc(), E->getRParenLoc(), Result.get()); 4446} 4447 4448ExprResult Sema::ActOnParenOrParenListExpr(SourceLocation L, 4449 SourceLocation R, 4450 MultiExprArg Val) { 4451 unsigned nexprs = Val.size(); 4452 Expr **exprs = reinterpret_cast<Expr**>(Val.release()); 4453 assert((exprs != 0) && "ActOnParenOrParenListExpr() missing expr list"); 4454 Expr *expr; 4455 if (nexprs == 1) 4456 expr = new (Context) ParenExpr(L, R, exprs[0]); 4457 else 4458 expr = new (Context) ParenListExpr(Context, L, exprs, nexprs, R, 4459 exprs[nexprs-1]->getType()); 4460 return Owned(expr); 4461} 4462 4463/// \brief Emit a specialized diagnostic when one expression is a null pointer 4464/// constant and the other is not a pointer. Returns true if a diagnostic is 4465/// emitted. 4466bool Sema::DiagnoseConditionalForNull(Expr *LHSExpr, Expr *RHSExpr, 4467 SourceLocation QuestionLoc) { 4468 Expr *NullExpr = LHSExpr; 4469 Expr *NonPointerExpr = RHSExpr; 4470 Expr::NullPointerConstantKind NullKind = 4471 NullExpr->isNullPointerConstant(Context, 4472 Expr::NPC_ValueDependentIsNotNull); 4473 4474 if (NullKind == Expr::NPCK_NotNull) { 4475 NullExpr = RHSExpr; 4476 NonPointerExpr = LHSExpr; 4477 NullKind = 4478 NullExpr->isNullPointerConstant(Context, 4479 Expr::NPC_ValueDependentIsNotNull); 4480 } 4481 4482 if (NullKind == Expr::NPCK_NotNull) 4483 return false; 4484 4485 if (NullKind == Expr::NPCK_ZeroInteger) { 4486 // In this case, check to make sure that we got here from a "NULL" 4487 // string in the source code. 4488 NullExpr = NullExpr->IgnoreParenImpCasts(); 4489 SourceLocation loc = NullExpr->getExprLoc(); 4490 if (!findMacroSpelling(loc, "NULL")) 4491 return false; 4492 } 4493 4494 int DiagType = (NullKind == Expr::NPCK_CXX0X_nullptr); 4495 Diag(QuestionLoc, diag::err_typecheck_cond_incompatible_operands_null) 4496 << NonPointerExpr->getType() << DiagType 4497 << NonPointerExpr->getSourceRange(); 4498 return true; 4499} 4500 4501/// \brief Return false if the condition expression is valid, true otherwise. 4502static bool checkCondition(Sema &S, Expr *Cond) { 4503 QualType CondTy = Cond->getType(); 4504 4505 // C99 6.5.15p2 4506 if (CondTy->isScalarType()) return false; 4507 4508 // OpenCL: Sec 6.3.i says the condition is allowed to be a vector or scalar. 4509 if (S.getLangOptions().OpenCL && CondTy->isVectorType()) 4510 return false; 4511 4512 // Emit the proper error message. 4513 S.Diag(Cond->getLocStart(), S.getLangOptions().OpenCL ? 4514 diag::err_typecheck_cond_expect_scalar : 4515 diag::err_typecheck_cond_expect_scalar_or_vector) 4516 << CondTy; 4517 return true; 4518} 4519 4520/// \brief Return false if the two expressions can be converted to a vector, 4521/// true otherwise 4522static bool checkConditionalConvertScalarsToVectors(Sema &S, ExprResult &LHS, 4523 ExprResult &RHS, 4524 QualType CondTy) { 4525 // Both operands should be of scalar type. 4526 if (!LHS.get()->getType()->isScalarType()) { 4527 S.Diag(LHS.get()->getLocStart(), diag::err_typecheck_cond_expect_scalar) 4528 << CondTy; 4529 return true; 4530 } 4531 if (!RHS.get()->getType()->isScalarType()) { 4532 S.Diag(RHS.get()->getLocStart(), diag::err_typecheck_cond_expect_scalar) 4533 << CondTy; 4534 return true; 4535 } 4536 4537 // Implicity convert these scalars to the type of the condition. 4538 LHS = S.ImpCastExprToType(LHS.take(), CondTy, CK_IntegralCast); 4539 RHS = S.ImpCastExprToType(RHS.take(), CondTy, CK_IntegralCast); 4540 return false; 4541} 4542 4543/// \brief Handle when one or both operands are void type. 4544static QualType checkConditionalVoidType(Sema &S, ExprResult &LHS, 4545 ExprResult &RHS) { 4546 Expr *LHSExpr = LHS.get(); 4547 Expr *RHSExpr = RHS.get(); 4548 4549 if (!LHSExpr->getType()->isVoidType()) 4550 S.Diag(RHSExpr->getLocStart(), diag::ext_typecheck_cond_one_void) 4551 << RHSExpr->getSourceRange(); 4552 if (!RHSExpr->getType()->isVoidType()) 4553 S.Diag(LHSExpr->getLocStart(), diag::ext_typecheck_cond_one_void) 4554 << LHSExpr->getSourceRange(); 4555 LHS = S.ImpCastExprToType(LHS.take(), S.Context.VoidTy, CK_ToVoid); 4556 RHS = S.ImpCastExprToType(RHS.take(), S.Context.VoidTy, CK_ToVoid); 4557 return S.Context.VoidTy; 4558} 4559 4560/// \brief Return false if the NullExpr can be promoted to PointerTy, 4561/// true otherwise. 4562static bool checkConditionalNullPointer(Sema &S, ExprResult &NullExpr, 4563 QualType PointerTy) { 4564 if ((!PointerTy->isAnyPointerType() && !PointerTy->isBlockPointerType()) || 4565 !NullExpr.get()->isNullPointerConstant(S.Context, 4566 Expr::NPC_ValueDependentIsNull)) 4567 return true; 4568 4569 NullExpr = S.ImpCastExprToType(NullExpr.take(), PointerTy, CK_NullToPointer); 4570 return false; 4571} 4572 4573/// \brief Checks compatibility between two pointers and return the resulting 4574/// type. 4575static QualType checkConditionalPointerCompatibility(Sema &S, ExprResult &LHS, 4576 ExprResult &RHS, 4577 SourceLocation Loc) { 4578 QualType LHSTy = LHS.get()->getType(); 4579 QualType RHSTy = RHS.get()->getType(); 4580 4581 if (S.Context.hasSameType(LHSTy, RHSTy)) { 4582 // Two identical pointers types are always compatible. 4583 return LHSTy; 4584 } 4585 4586 QualType lhptee, rhptee; 4587 4588 // Get the pointee types. 4589 if (const BlockPointerType *LHSBTy = LHSTy->getAs<BlockPointerType>()) { 4590 lhptee = LHSBTy->getPointeeType(); 4591 rhptee = RHSTy->castAs<BlockPointerType>()->getPointeeType(); 4592 } else { 4593 lhptee = LHSTy->castAs<PointerType>()->getPointeeType(); 4594 rhptee = RHSTy->castAs<PointerType>()->getPointeeType(); 4595 } 4596 4597 if (!S.Context.typesAreCompatible(lhptee.getUnqualifiedType(), 4598 rhptee.getUnqualifiedType())) { 4599 S.Diag(Loc, diag::warn_typecheck_cond_incompatible_pointers) 4600 << LHSTy << RHSTy << LHS.get()->getSourceRange() 4601 << RHS.get()->getSourceRange(); 4602 // In this situation, we assume void* type. No especially good 4603 // reason, but this is what gcc does, and we do have to pick 4604 // to get a consistent AST. 4605 QualType incompatTy = S.Context.getPointerType(S.Context.VoidTy); 4606 LHS = S.ImpCastExprToType(LHS.take(), incompatTy, CK_BitCast); 4607 RHS = S.ImpCastExprToType(RHS.take(), incompatTy, CK_BitCast); 4608 return incompatTy; 4609 } 4610 4611 // The pointer types are compatible. 4612 // C99 6.5.15p6: If both operands are pointers to compatible types *or* to 4613 // differently qualified versions of compatible types, the result type is 4614 // a pointer to an appropriately qualified version of the *composite* 4615 // type. 4616 // FIXME: Need to calculate the composite type. 4617 // FIXME: Need to add qualifiers 4618 4619 LHS = S.ImpCastExprToType(LHS.take(), LHSTy, CK_BitCast); 4620 RHS = S.ImpCastExprToType(RHS.take(), LHSTy, CK_BitCast); 4621 return LHSTy; 4622} 4623 4624/// \brief Return the resulting type when the operands are both block pointers. 4625static QualType checkConditionalBlockPointerCompatibility(Sema &S, 4626 ExprResult &LHS, 4627 ExprResult &RHS, 4628 SourceLocation Loc) { 4629 QualType LHSTy = LHS.get()->getType(); 4630 QualType RHSTy = RHS.get()->getType(); 4631 4632 if (!LHSTy->isBlockPointerType() || !RHSTy->isBlockPointerType()) { 4633 if (LHSTy->isVoidPointerType() || RHSTy->isVoidPointerType()) { 4634 QualType destType = S.Context.getPointerType(S.Context.VoidTy); 4635 LHS = S.ImpCastExprToType(LHS.take(), destType, CK_BitCast); 4636 RHS = S.ImpCastExprToType(RHS.take(), destType, CK_BitCast); 4637 return destType; 4638 } 4639 S.Diag(Loc, diag::err_typecheck_cond_incompatible_operands) 4640 << LHSTy << RHSTy << LHS.get()->getSourceRange() 4641 << RHS.get()->getSourceRange(); 4642 return QualType(); 4643 } 4644 4645 // We have 2 block pointer types. 4646 return checkConditionalPointerCompatibility(S, LHS, RHS, Loc); 4647} 4648 4649/// \brief Return the resulting type when the operands are both pointers. 4650static QualType 4651checkConditionalObjectPointersCompatibility(Sema &S, ExprResult &LHS, 4652 ExprResult &RHS, 4653 SourceLocation Loc) { 4654 // get the pointer types 4655 QualType LHSTy = LHS.get()->getType(); 4656 QualType RHSTy = RHS.get()->getType(); 4657 4658 // get the "pointed to" types 4659 QualType lhptee = LHSTy->getAs<PointerType>()->getPointeeType(); 4660 QualType rhptee = RHSTy->getAs<PointerType>()->getPointeeType(); 4661 4662 // ignore qualifiers on void (C99 6.5.15p3, clause 6) 4663 if (lhptee->isVoidType() && rhptee->isIncompleteOrObjectType()) { 4664 // Figure out necessary qualifiers (C99 6.5.15p6) 4665 QualType destPointee 4666 = S.Context.getQualifiedType(lhptee, rhptee.getQualifiers()); 4667 QualType destType = S.Context.getPointerType(destPointee); 4668 // Add qualifiers if necessary. 4669 LHS = S.ImpCastExprToType(LHS.take(), destType, CK_NoOp); 4670 // Promote to void*. 4671 RHS = S.ImpCastExprToType(RHS.take(), destType, CK_BitCast); 4672 return destType; 4673 } 4674 if (rhptee->isVoidType() && lhptee->isIncompleteOrObjectType()) { 4675 QualType destPointee 4676 = S.Context.getQualifiedType(rhptee, lhptee.getQualifiers()); 4677 QualType destType = S.Context.getPointerType(destPointee); 4678 // Add qualifiers if necessary. 4679 RHS = S.ImpCastExprToType(RHS.take(), destType, CK_NoOp); 4680 // Promote to void*. 4681 LHS = S.ImpCastExprToType(LHS.take(), destType, CK_BitCast); 4682 return destType; 4683 } 4684 4685 return checkConditionalPointerCompatibility(S, LHS, RHS, Loc); 4686} 4687 4688/// \brief Return false if the first expression is not an integer and the second 4689/// expression is not a pointer, true otherwise. 4690static bool checkPointerIntegerMismatch(Sema &S, ExprResult &Int, 4691 Expr* PointerExpr, SourceLocation Loc, 4692 bool IsIntFirstExpr) { 4693 if (!PointerExpr->getType()->isPointerType() || 4694 !Int.get()->getType()->isIntegerType()) 4695 return false; 4696 4697 Expr *Expr1 = IsIntFirstExpr ? Int.get() : PointerExpr; 4698 Expr *Expr2 = IsIntFirstExpr ? PointerExpr : Int.get(); 4699 4700 S.Diag(Loc, diag::warn_typecheck_cond_pointer_integer_mismatch) 4701 << Expr1->getType() << Expr2->getType() 4702 << Expr1->getSourceRange() << Expr2->getSourceRange(); 4703 Int = S.ImpCastExprToType(Int.take(), PointerExpr->getType(), 4704 CK_IntegralToPointer); 4705 return true; 4706} 4707 4708/// Note that LHS is not null here, even if this is the gnu "x ?: y" extension. 4709/// In that case, LHS = cond. 4710/// C99 6.5.15 4711QualType Sema::CheckConditionalOperands(ExprResult &Cond, ExprResult &LHS, 4712 ExprResult &RHS, ExprValueKind &VK, 4713 ExprObjectKind &OK, 4714 SourceLocation QuestionLoc) { 4715 4716 ExprResult LHSResult = CheckPlaceholderExpr(LHS.get()); 4717 if (!LHSResult.isUsable()) return QualType(); 4718 LHS = move(LHSResult); 4719 4720 ExprResult RHSResult = CheckPlaceholderExpr(RHS.get()); 4721 if (!RHSResult.isUsable()) return QualType(); 4722 RHS = move(RHSResult); 4723 4724 // C++ is sufficiently different to merit its own checker. 4725 if (getLangOptions().CPlusPlus) 4726 return CXXCheckConditionalOperands(Cond, LHS, RHS, VK, OK, QuestionLoc); 4727 4728 VK = VK_RValue; 4729 OK = OK_Ordinary; 4730 4731 Cond = UsualUnaryConversions(Cond.take()); 4732 if (Cond.isInvalid()) 4733 return QualType(); 4734 LHS = UsualUnaryConversions(LHS.take()); 4735 if (LHS.isInvalid()) 4736 return QualType(); 4737 RHS = UsualUnaryConversions(RHS.take()); 4738 if (RHS.isInvalid()) 4739 return QualType(); 4740 4741 QualType CondTy = Cond.get()->getType(); 4742 QualType LHSTy = LHS.get()->getType(); 4743 QualType RHSTy = RHS.get()->getType(); 4744 4745 // first, check the condition. 4746 if (checkCondition(*this, Cond.get())) 4747 return QualType(); 4748 4749 // Now check the two expressions. 4750 if (LHSTy->isVectorType() || RHSTy->isVectorType()) 4751 return CheckVectorOperands(LHS, RHS, QuestionLoc, /*isCompAssign*/false); 4752 4753 // OpenCL: If the condition is a vector, and both operands are scalar, 4754 // attempt to implicity convert them to the vector type to act like the 4755 // built in select. 4756 if (getLangOptions().OpenCL && CondTy->isVectorType()) 4757 if (checkConditionalConvertScalarsToVectors(*this, LHS, RHS, CondTy)) 4758 return QualType(); 4759 4760 // If both operands have arithmetic type, do the usual arithmetic conversions 4761 // to find a common type: C99 6.5.15p3,5. 4762 if (LHSTy->isArithmeticType() && RHSTy->isArithmeticType()) { 4763 UsualArithmeticConversions(LHS, RHS); 4764 if (LHS.isInvalid() || RHS.isInvalid()) 4765 return QualType(); 4766 return LHS.get()->getType(); 4767 } 4768 4769 // If both operands are the same structure or union type, the result is that 4770 // type. 4771 if (const RecordType *LHSRT = LHSTy->getAs<RecordType>()) { // C99 6.5.15p3 4772 if (const RecordType *RHSRT = RHSTy->getAs<RecordType>()) 4773 if (LHSRT->getDecl() == RHSRT->getDecl()) 4774 // "If both the operands have structure or union type, the result has 4775 // that type." This implies that CV qualifiers are dropped. 4776 return LHSTy.getUnqualifiedType(); 4777 // FIXME: Type of conditional expression must be complete in C mode. 4778 } 4779 4780 // C99 6.5.15p5: "If both operands have void type, the result has void type." 4781 // The following || allows only one side to be void (a GCC-ism). 4782 if (LHSTy->isVoidType() || RHSTy->isVoidType()) { 4783 return checkConditionalVoidType(*this, LHS, RHS); 4784 } 4785 4786 // C99 6.5.15p6 - "if one operand is a null pointer constant, the result has 4787 // the type of the other operand." 4788 if (!checkConditionalNullPointer(*this, RHS, LHSTy)) return LHSTy; 4789 if (!checkConditionalNullPointer(*this, LHS, RHSTy)) return RHSTy; 4790 4791 // All objective-c pointer type analysis is done here. 4792 QualType compositeType = FindCompositeObjCPointerType(LHS, RHS, 4793 QuestionLoc); 4794 if (LHS.isInvalid() || RHS.isInvalid()) 4795 return QualType(); 4796 if (!compositeType.isNull()) 4797 return compositeType; 4798 4799 4800 // Handle block pointer types. 4801 if (LHSTy->isBlockPointerType() || RHSTy->isBlockPointerType()) 4802 return checkConditionalBlockPointerCompatibility(*this, LHS, RHS, 4803 QuestionLoc); 4804 4805 // Check constraints for C object pointers types (C99 6.5.15p3,6). 4806 if (LHSTy->isPointerType() && RHSTy->isPointerType()) 4807 return checkConditionalObjectPointersCompatibility(*this, LHS, RHS, 4808 QuestionLoc); 4809 4810 // GCC compatibility: soften pointer/integer mismatch. Note that 4811 // null pointers have been filtered out by this point. 4812 if (checkPointerIntegerMismatch(*this, LHS, RHS.get(), QuestionLoc, 4813 /*isIntFirstExpr=*/true)) 4814 return RHSTy; 4815 if (checkPointerIntegerMismatch(*this, RHS, LHS.get(), QuestionLoc, 4816 /*isIntFirstExpr=*/false)) 4817 return LHSTy; 4818 4819 // Emit a better diagnostic if one of the expressions is a null pointer 4820 // constant and the other is not a pointer type. In this case, the user most 4821 // likely forgot to take the address of the other expression. 4822 if (DiagnoseConditionalForNull(LHS.get(), RHS.get(), QuestionLoc)) 4823 return QualType(); 4824 4825 // Otherwise, the operands are not compatible. 4826 Diag(QuestionLoc, diag::err_typecheck_cond_incompatible_operands) 4827 << LHSTy << RHSTy << LHS.get()->getSourceRange() 4828 << RHS.get()->getSourceRange(); 4829 return QualType(); 4830} 4831 4832/// FindCompositeObjCPointerType - Helper method to find composite type of 4833/// two objective-c pointer types of the two input expressions. 4834QualType Sema::FindCompositeObjCPointerType(ExprResult &LHS, ExprResult &RHS, 4835 SourceLocation QuestionLoc) { 4836 QualType LHSTy = LHS.get()->getType(); 4837 QualType RHSTy = RHS.get()->getType(); 4838 4839 // Handle things like Class and struct objc_class*. Here we case the result 4840 // to the pseudo-builtin, because that will be implicitly cast back to the 4841 // redefinition type if an attempt is made to access its fields. 4842 if (LHSTy->isObjCClassType() && 4843 (Context.hasSameType(RHSTy, Context.getObjCClassRedefinitionType()))) { 4844 RHS = ImpCastExprToType(RHS.take(), LHSTy, CK_CPointerToObjCPointerCast); 4845 return LHSTy; 4846 } 4847 if (RHSTy->isObjCClassType() && 4848 (Context.hasSameType(LHSTy, Context.getObjCClassRedefinitionType()))) { 4849 LHS = ImpCastExprToType(LHS.take(), RHSTy, CK_CPointerToObjCPointerCast); 4850 return RHSTy; 4851 } 4852 // And the same for struct objc_object* / id 4853 if (LHSTy->isObjCIdType() && 4854 (Context.hasSameType(RHSTy, Context.getObjCIdRedefinitionType()))) { 4855 RHS = ImpCastExprToType(RHS.take(), LHSTy, CK_CPointerToObjCPointerCast); 4856 return LHSTy; 4857 } 4858 if (RHSTy->isObjCIdType() && 4859 (Context.hasSameType(LHSTy, Context.getObjCIdRedefinitionType()))) { 4860 LHS = ImpCastExprToType(LHS.take(), RHSTy, CK_CPointerToObjCPointerCast); 4861 return RHSTy; 4862 } 4863 // And the same for struct objc_selector* / SEL 4864 if (Context.isObjCSelType(LHSTy) && 4865 (Context.hasSameType(RHSTy, Context.getObjCSelRedefinitionType()))) { 4866 RHS = ImpCastExprToType(RHS.take(), LHSTy, CK_BitCast); 4867 return LHSTy; 4868 } 4869 if (Context.isObjCSelType(RHSTy) && 4870 (Context.hasSameType(LHSTy, Context.getObjCSelRedefinitionType()))) { 4871 LHS = ImpCastExprToType(LHS.take(), RHSTy, CK_BitCast); 4872 return RHSTy; 4873 } 4874 // Check constraints for Objective-C object pointers types. 4875 if (LHSTy->isObjCObjectPointerType() && RHSTy->isObjCObjectPointerType()) { 4876 4877 if (Context.getCanonicalType(LHSTy) == Context.getCanonicalType(RHSTy)) { 4878 // Two identical object pointer types are always compatible. 4879 return LHSTy; 4880 } 4881 const ObjCObjectPointerType *LHSOPT = LHSTy->castAs<ObjCObjectPointerType>(); 4882 const ObjCObjectPointerType *RHSOPT = RHSTy->castAs<ObjCObjectPointerType>(); 4883 QualType compositeType = LHSTy; 4884 4885 // If both operands are interfaces and either operand can be 4886 // assigned to the other, use that type as the composite 4887 // type. This allows 4888 // xxx ? (A*) a : (B*) b 4889 // where B is a subclass of A. 4890 // 4891 // Additionally, as for assignment, if either type is 'id' 4892 // allow silent coercion. Finally, if the types are 4893 // incompatible then make sure to use 'id' as the composite 4894 // type so the result is acceptable for sending messages to. 4895 4896 // FIXME: Consider unifying with 'areComparableObjCPointerTypes'. 4897 // It could return the composite type. 4898 if (Context.canAssignObjCInterfaces(LHSOPT, RHSOPT)) { 4899 compositeType = RHSOPT->isObjCBuiltinType() ? RHSTy : LHSTy; 4900 } else if (Context.canAssignObjCInterfaces(RHSOPT, LHSOPT)) { 4901 compositeType = LHSOPT->isObjCBuiltinType() ? LHSTy : RHSTy; 4902 } else if ((LHSTy->isObjCQualifiedIdType() || 4903 RHSTy->isObjCQualifiedIdType()) && 4904 Context.ObjCQualifiedIdTypesAreCompatible(LHSTy, RHSTy, true)) { 4905 // Need to handle "id<xx>" explicitly. 4906 // GCC allows qualified id and any Objective-C type to devolve to 4907 // id. Currently localizing to here until clear this should be 4908 // part of ObjCQualifiedIdTypesAreCompatible. 4909 compositeType = Context.getObjCIdType(); 4910 } else if (LHSTy->isObjCIdType() || RHSTy->isObjCIdType()) { 4911 compositeType = Context.getObjCIdType(); 4912 } else if (!(compositeType = 4913 Context.areCommonBaseCompatible(LHSOPT, RHSOPT)).isNull()) 4914 ; 4915 else { 4916 Diag(QuestionLoc, diag::ext_typecheck_cond_incompatible_operands) 4917 << LHSTy << RHSTy 4918 << LHS.get()->getSourceRange() << RHS.get()->getSourceRange(); 4919 QualType incompatTy = Context.getObjCIdType(); 4920 LHS = ImpCastExprToType(LHS.take(), incompatTy, CK_BitCast); 4921 RHS = ImpCastExprToType(RHS.take(), incompatTy, CK_BitCast); 4922 return incompatTy; 4923 } 4924 // The object pointer types are compatible. 4925 LHS = ImpCastExprToType(LHS.take(), compositeType, CK_BitCast); 4926 RHS = ImpCastExprToType(RHS.take(), compositeType, CK_BitCast); 4927 return compositeType; 4928 } 4929 // Check Objective-C object pointer types and 'void *' 4930 if (LHSTy->isVoidPointerType() && RHSTy->isObjCObjectPointerType()) { 4931 QualType lhptee = LHSTy->getAs<PointerType>()->getPointeeType(); 4932 QualType rhptee = RHSTy->getAs<ObjCObjectPointerType>()->getPointeeType(); 4933 QualType destPointee 4934 = Context.getQualifiedType(lhptee, rhptee.getQualifiers()); 4935 QualType destType = Context.getPointerType(destPointee); 4936 // Add qualifiers if necessary. 4937 LHS = ImpCastExprToType(LHS.take(), destType, CK_NoOp); 4938 // Promote to void*. 4939 RHS = ImpCastExprToType(RHS.take(), destType, CK_BitCast); 4940 return destType; 4941 } 4942 if (LHSTy->isObjCObjectPointerType() && RHSTy->isVoidPointerType()) { 4943 QualType lhptee = LHSTy->getAs<ObjCObjectPointerType>()->getPointeeType(); 4944 QualType rhptee = RHSTy->getAs<PointerType>()->getPointeeType(); 4945 QualType destPointee 4946 = Context.getQualifiedType(rhptee, lhptee.getQualifiers()); 4947 QualType destType = Context.getPointerType(destPointee); 4948 // Add qualifiers if necessary. 4949 RHS = ImpCastExprToType(RHS.take(), destType, CK_NoOp); 4950 // Promote to void*. 4951 LHS = ImpCastExprToType(LHS.take(), destType, CK_BitCast); 4952 return destType; 4953 } 4954 return QualType(); 4955} 4956 4957/// SuggestParentheses - Emit a note with a fixit hint that wraps 4958/// ParenRange in parentheses. 4959static void SuggestParentheses(Sema &Self, SourceLocation Loc, 4960 const PartialDiagnostic &Note, 4961 SourceRange ParenRange) { 4962 SourceLocation EndLoc = Self.PP.getLocForEndOfToken(ParenRange.getEnd()); 4963 if (ParenRange.getBegin().isFileID() && ParenRange.getEnd().isFileID() && 4964 EndLoc.isValid()) { 4965 Self.Diag(Loc, Note) 4966 << FixItHint::CreateInsertion(ParenRange.getBegin(), "(") 4967 << FixItHint::CreateInsertion(EndLoc, ")"); 4968 } else { 4969 // We can't display the parentheses, so just show the bare note. 4970 Self.Diag(Loc, Note) << ParenRange; 4971 } 4972} 4973 4974static bool IsArithmeticOp(BinaryOperatorKind Opc) { 4975 return Opc >= BO_Mul && Opc <= BO_Shr; 4976} 4977 4978/// IsArithmeticBinaryExpr - Returns true if E is an arithmetic binary 4979/// expression, either using a built-in or overloaded operator, 4980/// and sets *OpCode to the opcode and *RHSExprs to the right-hand side 4981/// expression. 4982static bool IsArithmeticBinaryExpr(Expr *E, BinaryOperatorKind *Opcode, 4983 Expr **RHSExprs) { 4984 // Don't strip parenthesis: we should not warn if E is in parenthesis. 4985 E = E->IgnoreImpCasts(); 4986 E = E->IgnoreConversionOperator(); 4987 E = E->IgnoreImpCasts(); 4988 4989 // Built-in binary operator. 4990 if (BinaryOperator *OP = dyn_cast<BinaryOperator>(E)) { 4991 if (IsArithmeticOp(OP->getOpcode())) { 4992 *Opcode = OP->getOpcode(); 4993 *RHSExprs = OP->getRHS(); 4994 return true; 4995 } 4996 } 4997 4998 // Overloaded operator. 4999 if (CXXOperatorCallExpr *Call = dyn_cast<CXXOperatorCallExpr>(E)) { 5000 if (Call->getNumArgs() != 2) 5001 return false; 5002 5003 // Make sure this is really a binary operator that is safe to pass into 5004 // BinaryOperator::getOverloadedOpcode(), e.g. it's not a subscript op. 5005 OverloadedOperatorKind OO = Call->getOperator(); 5006 if (OO < OO_Plus || OO > OO_Arrow) 5007 return false; 5008 5009 BinaryOperatorKind OpKind = BinaryOperator::getOverloadedOpcode(OO); 5010 if (IsArithmeticOp(OpKind)) { 5011 *Opcode = OpKind; 5012 *RHSExprs = Call->getArg(1); 5013 return true; 5014 } 5015 } 5016 5017 return false; 5018} 5019 5020static bool IsLogicOp(BinaryOperatorKind Opc) { 5021 return (Opc >= BO_LT && Opc <= BO_NE) || (Opc >= BO_LAnd && Opc <= BO_LOr); 5022} 5023 5024/// ExprLooksBoolean - Returns true if E looks boolean, i.e. it has boolean type 5025/// or is a logical expression such as (x==y) which has int type, but is 5026/// commonly interpreted as boolean. 5027static bool ExprLooksBoolean(Expr *E) { 5028 E = E->IgnoreParenImpCasts(); 5029 5030 if (E->getType()->isBooleanType()) 5031 return true; 5032 if (BinaryOperator *OP = dyn_cast<BinaryOperator>(E)) 5033 return IsLogicOp(OP->getOpcode()); 5034 if (UnaryOperator *OP = dyn_cast<UnaryOperator>(E)) 5035 return OP->getOpcode() == UO_LNot; 5036 5037 return false; 5038} 5039 5040/// DiagnoseConditionalPrecedence - Emit a warning when a conditional operator 5041/// and binary operator are mixed in a way that suggests the programmer assumed 5042/// the conditional operator has higher precedence, for example: 5043/// "int x = a + someBinaryCondition ? 1 : 2". 5044static void DiagnoseConditionalPrecedence(Sema &Self, 5045 SourceLocation OpLoc, 5046 Expr *Condition, 5047 Expr *LHSExpr, 5048 Expr *RHSExpr) { 5049 BinaryOperatorKind CondOpcode; 5050 Expr *CondRHS; 5051 5052 if (!IsArithmeticBinaryExpr(Condition, &CondOpcode, &CondRHS)) 5053 return; 5054 if (!ExprLooksBoolean(CondRHS)) 5055 return; 5056 5057 // The condition is an arithmetic binary expression, with a right- 5058 // hand side that looks boolean, so warn. 5059 5060 Self.Diag(OpLoc, diag::warn_precedence_conditional) 5061 << Condition->getSourceRange() 5062 << BinaryOperator::getOpcodeStr(CondOpcode); 5063 5064 SuggestParentheses(Self, OpLoc, 5065 Self.PDiag(diag::note_precedence_conditional_silence) 5066 << BinaryOperator::getOpcodeStr(CondOpcode), 5067 SourceRange(Condition->getLocStart(), Condition->getLocEnd())); 5068 5069 SuggestParentheses(Self, OpLoc, 5070 Self.PDiag(diag::note_precedence_conditional_first), 5071 SourceRange(CondRHS->getLocStart(), RHSExpr->getLocEnd())); 5072} 5073 5074/// ActOnConditionalOp - Parse a ?: operation. Note that 'LHS' may be null 5075/// in the case of a the GNU conditional expr extension. 5076ExprResult Sema::ActOnConditionalOp(SourceLocation QuestionLoc, 5077 SourceLocation ColonLoc, 5078 Expr *CondExpr, Expr *LHSExpr, 5079 Expr *RHSExpr) { 5080 // If this is the gnu "x ?: y" extension, analyze the types as though the LHS 5081 // was the condition. 5082 OpaqueValueExpr *opaqueValue = 0; 5083 Expr *commonExpr = 0; 5084 if (LHSExpr == 0) { 5085 commonExpr = CondExpr; 5086 5087 // We usually want to apply unary conversions *before* saving, except 5088 // in the special case of a C++ l-value conditional. 5089 if (!(getLangOptions().CPlusPlus 5090 && !commonExpr->isTypeDependent() 5091 && commonExpr->getValueKind() == RHSExpr->getValueKind() 5092 && commonExpr->isGLValue() 5093 && commonExpr->isOrdinaryOrBitFieldObject() 5094 && RHSExpr->isOrdinaryOrBitFieldObject() 5095 && Context.hasSameType(commonExpr->getType(), RHSExpr->getType()))) { 5096 ExprResult commonRes = UsualUnaryConversions(commonExpr); 5097 if (commonRes.isInvalid()) 5098 return ExprError(); 5099 commonExpr = commonRes.take(); 5100 } 5101 5102 opaqueValue = new (Context) OpaqueValueExpr(commonExpr->getExprLoc(), 5103 commonExpr->getType(), 5104 commonExpr->getValueKind(), 5105 commonExpr->getObjectKind()); 5106 LHSExpr = CondExpr = opaqueValue; 5107 } 5108 5109 ExprValueKind VK = VK_RValue; 5110 ExprObjectKind OK = OK_Ordinary; 5111 ExprResult Cond = Owned(CondExpr), LHS = Owned(LHSExpr), RHS = Owned(RHSExpr); 5112 QualType result = CheckConditionalOperands(Cond, LHS, RHS, 5113 VK, OK, QuestionLoc); 5114 if (result.isNull() || Cond.isInvalid() || LHS.isInvalid() || 5115 RHS.isInvalid()) 5116 return ExprError(); 5117 5118 DiagnoseConditionalPrecedence(*this, QuestionLoc, Cond.get(), LHS.get(), 5119 RHS.get()); 5120 5121 if (!commonExpr) 5122 return Owned(new (Context) ConditionalOperator(Cond.take(), QuestionLoc, 5123 LHS.take(), ColonLoc, 5124 RHS.take(), result, VK, OK)); 5125 5126 return Owned(new (Context) 5127 BinaryConditionalOperator(commonExpr, opaqueValue, Cond.take(), LHS.take(), 5128 RHS.take(), QuestionLoc, ColonLoc, result, VK, 5129 OK)); 5130} 5131 5132// checkPointerTypesForAssignment - This is a very tricky routine (despite 5133// being closely modeled after the C99 spec:-). The odd characteristic of this 5134// routine is it effectively iqnores the qualifiers on the top level pointee. 5135// This circumvents the usual type rules specified in 6.2.7p1 & 6.7.5.[1-3]. 5136// FIXME: add a couple examples in this comment. 5137static Sema::AssignConvertType 5138checkPointerTypesForAssignment(Sema &S, QualType LHSType, QualType RHSType) { 5139 assert(LHSType.isCanonical() && "LHS not canonicalized!"); 5140 assert(RHSType.isCanonical() && "RHS not canonicalized!"); 5141 5142 // get the "pointed to" type (ignoring qualifiers at the top level) 5143 const Type *lhptee, *rhptee; 5144 Qualifiers lhq, rhq; 5145 llvm::tie(lhptee, lhq) = cast<PointerType>(LHSType)->getPointeeType().split(); 5146 llvm::tie(rhptee, rhq) = cast<PointerType>(RHSType)->getPointeeType().split(); 5147 5148 Sema::AssignConvertType ConvTy = Sema::Compatible; 5149 5150 // C99 6.5.16.1p1: This following citation is common to constraints 5151 // 3 & 4 (below). ...and the type *pointed to* by the left has all the 5152 // qualifiers of the type *pointed to* by the right; 5153 Qualifiers lq; 5154 5155 // As a special case, 'non-__weak A *' -> 'non-__weak const *' is okay. 5156 if (lhq.getObjCLifetime() != rhq.getObjCLifetime() && 5157 lhq.compatiblyIncludesObjCLifetime(rhq)) { 5158 // Ignore lifetime for further calculation. 5159 lhq.removeObjCLifetime(); 5160 rhq.removeObjCLifetime(); 5161 } 5162 5163 if (!lhq.compatiblyIncludes(rhq)) { 5164 // Treat address-space mismatches as fatal. TODO: address subspaces 5165 if (lhq.getAddressSpace() != rhq.getAddressSpace()) 5166 ConvTy = Sema::IncompatiblePointerDiscardsQualifiers; 5167 5168 // It's okay to add or remove GC or lifetime qualifiers when converting to 5169 // and from void*. 5170 else if (lhq.withoutObjCGCAttr().withoutObjCGLifetime() 5171 .compatiblyIncludes( 5172 rhq.withoutObjCGCAttr().withoutObjCGLifetime()) 5173 && (lhptee->isVoidType() || rhptee->isVoidType())) 5174 ; // keep old 5175 5176 // Treat lifetime mismatches as fatal. 5177 else if (lhq.getObjCLifetime() != rhq.getObjCLifetime()) 5178 ConvTy = Sema::IncompatiblePointerDiscardsQualifiers; 5179 5180 // For GCC compatibility, other qualifier mismatches are treated 5181 // as still compatible in C. 5182 else ConvTy = Sema::CompatiblePointerDiscardsQualifiers; 5183 } 5184 5185 // C99 6.5.16.1p1 (constraint 4): If one operand is a pointer to an object or 5186 // incomplete type and the other is a pointer to a qualified or unqualified 5187 // version of void... 5188 if (lhptee->isVoidType()) { 5189 if (rhptee->isIncompleteOrObjectType()) 5190 return ConvTy; 5191 5192 // As an extension, we allow cast to/from void* to function pointer. 5193 assert(rhptee->isFunctionType()); 5194 return Sema::FunctionVoidPointer; 5195 } 5196 5197 if (rhptee->isVoidType()) { 5198 if (lhptee->isIncompleteOrObjectType()) 5199 return ConvTy; 5200 5201 // As an extension, we allow cast to/from void* to function pointer. 5202 assert(lhptee->isFunctionType()); 5203 return Sema::FunctionVoidPointer; 5204 } 5205 5206 // C99 6.5.16.1p1 (constraint 3): both operands are pointers to qualified or 5207 // unqualified versions of compatible types, ... 5208 QualType ltrans = QualType(lhptee, 0), rtrans = QualType(rhptee, 0); 5209 if (!S.Context.typesAreCompatible(ltrans, rtrans)) { 5210 // Check if the pointee types are compatible ignoring the sign. 5211 // We explicitly check for char so that we catch "char" vs 5212 // "unsigned char" on systems where "char" is unsigned. 5213 if (lhptee->isCharType()) 5214 ltrans = S.Context.UnsignedCharTy; 5215 else if (lhptee->hasSignedIntegerRepresentation()) 5216 ltrans = S.Context.getCorrespondingUnsignedType(ltrans); 5217 5218 if (rhptee->isCharType()) 5219 rtrans = S.Context.UnsignedCharTy; 5220 else if (rhptee->hasSignedIntegerRepresentation()) 5221 rtrans = S.Context.getCorrespondingUnsignedType(rtrans); 5222 5223 if (ltrans == rtrans) { 5224 // Types are compatible ignoring the sign. Qualifier incompatibility 5225 // takes priority over sign incompatibility because the sign 5226 // warning can be disabled. 5227 if (ConvTy != Sema::Compatible) 5228 return ConvTy; 5229 5230 return Sema::IncompatiblePointerSign; 5231 } 5232 5233 // If we are a multi-level pointer, it's possible that our issue is simply 5234 // one of qualification - e.g. char ** -> const char ** is not allowed. If 5235 // the eventual target type is the same and the pointers have the same 5236 // level of indirection, this must be the issue. 5237 if (isa<PointerType>(lhptee) && isa<PointerType>(rhptee)) { 5238 do { 5239 lhptee = cast<PointerType>(lhptee)->getPointeeType().getTypePtr(); 5240 rhptee = cast<PointerType>(rhptee)->getPointeeType().getTypePtr(); 5241 } while (isa<PointerType>(lhptee) && isa<PointerType>(rhptee)); 5242 5243 if (lhptee == rhptee) 5244 return Sema::IncompatibleNestedPointerQualifiers; 5245 } 5246 5247 // General pointer incompatibility takes priority over qualifiers. 5248 return Sema::IncompatiblePointer; 5249 } 5250 if (!S.getLangOptions().CPlusPlus && 5251 S.IsNoReturnConversion(ltrans, rtrans, ltrans)) 5252 return Sema::IncompatiblePointer; 5253 return ConvTy; 5254} 5255 5256/// checkBlockPointerTypesForAssignment - This routine determines whether two 5257/// block pointer types are compatible or whether a block and normal pointer 5258/// are compatible. It is more restrict than comparing two function pointer 5259// types. 5260static Sema::AssignConvertType 5261checkBlockPointerTypesForAssignment(Sema &S, QualType LHSType, 5262 QualType RHSType) { 5263 assert(LHSType.isCanonical() && "LHS not canonicalized!"); 5264 assert(RHSType.isCanonical() && "RHS not canonicalized!"); 5265 5266 QualType lhptee, rhptee; 5267 5268 // get the "pointed to" type (ignoring qualifiers at the top level) 5269 lhptee = cast<BlockPointerType>(LHSType)->getPointeeType(); 5270 rhptee = cast<BlockPointerType>(RHSType)->getPointeeType(); 5271 5272 // In C++, the types have to match exactly. 5273 if (S.getLangOptions().CPlusPlus) 5274 return Sema::IncompatibleBlockPointer; 5275 5276 Sema::AssignConvertType ConvTy = Sema::Compatible; 5277 5278 // For blocks we enforce that qualifiers are identical. 5279 if (lhptee.getLocalQualifiers() != rhptee.getLocalQualifiers()) 5280 ConvTy = Sema::CompatiblePointerDiscardsQualifiers; 5281 5282 if (!S.Context.typesAreBlockPointerCompatible(LHSType, RHSType)) 5283 return Sema::IncompatibleBlockPointer; 5284 5285 return ConvTy; 5286} 5287 5288/// checkObjCPointerTypesForAssignment - Compares two objective-c pointer types 5289/// for assignment compatibility. 5290static Sema::AssignConvertType 5291checkObjCPointerTypesForAssignment(Sema &S, QualType LHSType, 5292 QualType RHSType) { 5293 assert(LHSType.isCanonical() && "LHS was not canonicalized!"); 5294 assert(RHSType.isCanonical() && "RHS was not canonicalized!"); 5295 5296 if (LHSType->isObjCBuiltinType()) { 5297 // Class is not compatible with ObjC object pointers. 5298 if (LHSType->isObjCClassType() && !RHSType->isObjCBuiltinType() && 5299 !RHSType->isObjCQualifiedClassType()) 5300 return Sema::IncompatiblePointer; 5301 return Sema::Compatible; 5302 } 5303 if (RHSType->isObjCBuiltinType()) { 5304 if (RHSType->isObjCClassType() && !LHSType->isObjCBuiltinType() && 5305 !LHSType->isObjCQualifiedClassType()) 5306 return Sema::IncompatiblePointer; 5307 return Sema::Compatible; 5308 } 5309 QualType lhptee = LHSType->getAs<ObjCObjectPointerType>()->getPointeeType(); 5310 QualType rhptee = RHSType->getAs<ObjCObjectPointerType>()->getPointeeType(); 5311 5312 if (!lhptee.isAtLeastAsQualifiedAs(rhptee)) 5313 return Sema::CompatiblePointerDiscardsQualifiers; 5314 5315 if (S.Context.typesAreCompatible(LHSType, RHSType)) 5316 return Sema::Compatible; 5317 if (LHSType->isObjCQualifiedIdType() || RHSType->isObjCQualifiedIdType()) 5318 return Sema::IncompatibleObjCQualifiedId; 5319 return Sema::IncompatiblePointer; 5320} 5321 5322Sema::AssignConvertType 5323Sema::CheckAssignmentConstraints(SourceLocation Loc, 5324 QualType LHSType, QualType RHSType) { 5325 // Fake up an opaque expression. We don't actually care about what 5326 // cast operations are required, so if CheckAssignmentConstraints 5327 // adds casts to this they'll be wasted, but fortunately that doesn't 5328 // usually happen on valid code. 5329 OpaqueValueExpr RHSExpr(Loc, RHSType, VK_RValue); 5330 ExprResult RHSPtr = &RHSExpr; 5331 CastKind K = CK_Invalid; 5332 5333 return CheckAssignmentConstraints(LHSType, RHSPtr, K); 5334} 5335 5336/// CheckAssignmentConstraints (C99 6.5.16) - This routine currently 5337/// has code to accommodate several GCC extensions when type checking 5338/// pointers. Here are some objectionable examples that GCC considers warnings: 5339/// 5340/// int a, *pint; 5341/// short *pshort; 5342/// struct foo *pfoo; 5343/// 5344/// pint = pshort; // warning: assignment from incompatible pointer type 5345/// a = pint; // warning: assignment makes integer from pointer without a cast 5346/// pint = a; // warning: assignment makes pointer from integer without a cast 5347/// pint = pfoo; // warning: assignment from incompatible pointer type 5348/// 5349/// As a result, the code for dealing with pointers is more complex than the 5350/// C99 spec dictates. 5351/// 5352/// Sets 'Kind' for any result kind except Incompatible. 5353Sema::AssignConvertType 5354Sema::CheckAssignmentConstraints(QualType LHSType, ExprResult &RHS, 5355 CastKind &Kind) { 5356 QualType RHSType = RHS.get()->getType(); 5357 QualType OrigLHSType = LHSType; 5358 5359 // Get canonical types. We're not formatting these types, just comparing 5360 // them. 5361 LHSType = Context.getCanonicalType(LHSType).getUnqualifiedType(); 5362 RHSType = Context.getCanonicalType(RHSType).getUnqualifiedType(); 5363 5364 // We can't do assignment from/to atomics yet. 5365 if (LHSType->isAtomicType()) 5366 return Incompatible; 5367 5368 // Common case: no conversion required. 5369 if (LHSType == RHSType) { 5370 Kind = CK_NoOp; 5371 return Compatible; 5372 } 5373 5374 // If the left-hand side is a reference type, then we are in a 5375 // (rare!) case where we've allowed the use of references in C, 5376 // e.g., as a parameter type in a built-in function. In this case, 5377 // just make sure that the type referenced is compatible with the 5378 // right-hand side type. The caller is responsible for adjusting 5379 // LHSType so that the resulting expression does not have reference 5380 // type. 5381 if (const ReferenceType *LHSTypeRef = LHSType->getAs<ReferenceType>()) { 5382 if (Context.typesAreCompatible(LHSTypeRef->getPointeeType(), RHSType)) { 5383 Kind = CK_LValueBitCast; 5384 return Compatible; 5385 } 5386 return Incompatible; 5387 } 5388 5389 // Allow scalar to ExtVector assignments, and assignments of an ExtVector type 5390 // to the same ExtVector type. 5391 if (LHSType->isExtVectorType()) { 5392 if (RHSType->isExtVectorType()) 5393 return Incompatible; 5394 if (RHSType->isArithmeticType()) { 5395 // CK_VectorSplat does T -> vector T, so first cast to the 5396 // element type. 5397 QualType elType = cast<ExtVectorType>(LHSType)->getElementType(); 5398 if (elType != RHSType) { 5399 Kind = PrepareScalarCast(RHS, elType); 5400 RHS = ImpCastExprToType(RHS.take(), elType, Kind); 5401 } 5402 Kind = CK_VectorSplat; 5403 return Compatible; 5404 } 5405 } 5406 5407 // Conversions to or from vector type. 5408 if (LHSType->isVectorType() || RHSType->isVectorType()) { 5409 if (LHSType->isVectorType() && RHSType->isVectorType()) { 5410 // Allow assignments of an AltiVec vector type to an equivalent GCC 5411 // vector type and vice versa 5412 if (Context.areCompatibleVectorTypes(LHSType, RHSType)) { 5413 Kind = CK_BitCast; 5414 return Compatible; 5415 } 5416 5417 // If we are allowing lax vector conversions, and LHS and RHS are both 5418 // vectors, the total size only needs to be the same. This is a bitcast; 5419 // no bits are changed but the result type is different. 5420 if (getLangOptions().LaxVectorConversions && 5421 (Context.getTypeSize(LHSType) == Context.getTypeSize(RHSType))) { 5422 Kind = CK_BitCast; 5423 return IncompatibleVectors; 5424 } 5425 } 5426 return Incompatible; 5427 } 5428 5429 // Arithmetic conversions. 5430 if (LHSType->isArithmeticType() && RHSType->isArithmeticType() && 5431 !(getLangOptions().CPlusPlus && LHSType->isEnumeralType())) { 5432 Kind = PrepareScalarCast(RHS, LHSType); 5433 return Compatible; 5434 } 5435 5436 // Conversions to normal pointers. 5437 if (const PointerType *LHSPointer = dyn_cast<PointerType>(LHSType)) { 5438 // U* -> T* 5439 if (isa<PointerType>(RHSType)) { 5440 Kind = CK_BitCast; 5441 return checkPointerTypesForAssignment(*this, LHSType, RHSType); 5442 } 5443 5444 // int -> T* 5445 if (RHSType->isIntegerType()) { 5446 Kind = CK_IntegralToPointer; // FIXME: null? 5447 return IntToPointer; 5448 } 5449 5450 // C pointers are not compatible with ObjC object pointers, 5451 // with two exceptions: 5452 if (isa<ObjCObjectPointerType>(RHSType)) { 5453 // - conversions to void* 5454 if (LHSPointer->getPointeeType()->isVoidType()) { 5455 Kind = CK_BitCast; 5456 return Compatible; 5457 } 5458 5459 // - conversions from 'Class' to the redefinition type 5460 if (RHSType->isObjCClassType() && 5461 Context.hasSameType(LHSType, 5462 Context.getObjCClassRedefinitionType())) { 5463 Kind = CK_BitCast; 5464 return Compatible; 5465 } 5466 5467 Kind = CK_BitCast; 5468 return IncompatiblePointer; 5469 } 5470 5471 // U^ -> void* 5472 if (RHSType->getAs<BlockPointerType>()) { 5473 if (LHSPointer->getPointeeType()->isVoidType()) { 5474 Kind = CK_BitCast; 5475 return Compatible; 5476 } 5477 } 5478 5479 return Incompatible; 5480 } 5481 5482 // Conversions to block pointers. 5483 if (isa<BlockPointerType>(LHSType)) { 5484 // U^ -> T^ 5485 if (RHSType->isBlockPointerType()) { 5486 Kind = CK_BitCast; 5487 return checkBlockPointerTypesForAssignment(*this, LHSType, RHSType); 5488 } 5489 5490 // int or null -> T^ 5491 if (RHSType->isIntegerType()) { 5492 Kind = CK_IntegralToPointer; // FIXME: null 5493 return IntToBlockPointer; 5494 } 5495 5496 // id -> T^ 5497 if (getLangOptions().ObjC1 && RHSType->isObjCIdType()) { 5498 Kind = CK_AnyPointerToBlockPointerCast; 5499 return Compatible; 5500 } 5501 5502 // void* -> T^ 5503 if (const PointerType *RHSPT = RHSType->getAs<PointerType>()) 5504 if (RHSPT->getPointeeType()->isVoidType()) { 5505 Kind = CK_AnyPointerToBlockPointerCast; 5506 return Compatible; 5507 } 5508 5509 return Incompatible; 5510 } 5511 5512 // Conversions to Objective-C pointers. 5513 if (isa<ObjCObjectPointerType>(LHSType)) { 5514 // A* -> B* 5515 if (RHSType->isObjCObjectPointerType()) { 5516 Kind = CK_BitCast; 5517 Sema::AssignConvertType result = 5518 checkObjCPointerTypesForAssignment(*this, LHSType, RHSType); 5519 if (getLangOptions().ObjCAutoRefCount && 5520 result == Compatible && 5521 !CheckObjCARCUnavailableWeakConversion(OrigLHSType, RHSType)) 5522 result = IncompatibleObjCWeakRef; 5523 return result; 5524 } 5525 5526 // int or null -> A* 5527 if (RHSType->isIntegerType()) { 5528 Kind = CK_IntegralToPointer; // FIXME: null 5529 return IntToPointer; 5530 } 5531 5532 // In general, C pointers are not compatible with ObjC object pointers, 5533 // with two exceptions: 5534 if (isa<PointerType>(RHSType)) { 5535 Kind = CK_CPointerToObjCPointerCast; 5536 5537 // - conversions from 'void*' 5538 if (RHSType->isVoidPointerType()) { 5539 return Compatible; 5540 } 5541 5542 // - conversions to 'Class' from its redefinition type 5543 if (LHSType->isObjCClassType() && 5544 Context.hasSameType(RHSType, 5545 Context.getObjCClassRedefinitionType())) { 5546 return Compatible; 5547 } 5548 5549 return IncompatiblePointer; 5550 } 5551 5552 // T^ -> A* 5553 if (RHSType->isBlockPointerType()) { 5554 maybeExtendBlockObject(*this, RHS); 5555 Kind = CK_BlockPointerToObjCPointerCast; 5556 return Compatible; 5557 } 5558 5559 return Incompatible; 5560 } 5561 5562 // Conversions from pointers that are not covered by the above. 5563 if (isa<PointerType>(RHSType)) { 5564 // T* -> _Bool 5565 if (LHSType == Context.BoolTy) { 5566 Kind = CK_PointerToBoolean; 5567 return Compatible; 5568 } 5569 5570 // T* -> int 5571 if (LHSType->isIntegerType()) { 5572 Kind = CK_PointerToIntegral; 5573 return PointerToInt; 5574 } 5575 5576 return Incompatible; 5577 } 5578 5579 // Conversions from Objective-C pointers that are not covered by the above. 5580 if (isa<ObjCObjectPointerType>(RHSType)) { 5581 // T* -> _Bool 5582 if (LHSType == Context.BoolTy) { 5583 Kind = CK_PointerToBoolean; 5584 return Compatible; 5585 } 5586 5587 // T* -> int 5588 if (LHSType->isIntegerType()) { 5589 Kind = CK_PointerToIntegral; 5590 return PointerToInt; 5591 } 5592 5593 return Incompatible; 5594 } 5595 5596 // struct A -> struct B 5597 if (isa<TagType>(LHSType) && isa<TagType>(RHSType)) { 5598 if (Context.typesAreCompatible(LHSType, RHSType)) { 5599 Kind = CK_NoOp; 5600 return Compatible; 5601 } 5602 } 5603 5604 return Incompatible; 5605} 5606 5607/// \brief Constructs a transparent union from an expression that is 5608/// used to initialize the transparent union. 5609static void ConstructTransparentUnion(Sema &S, ASTContext &C, 5610 ExprResult &EResult, QualType UnionType, 5611 FieldDecl *Field) { 5612 // Build an initializer list that designates the appropriate member 5613 // of the transparent union. 5614 Expr *E = EResult.take(); 5615 InitListExpr *Initializer = new (C) InitListExpr(C, SourceLocation(), 5616 &E, 1, 5617 SourceLocation()); 5618 Initializer->setType(UnionType); 5619 Initializer->setInitializedFieldInUnion(Field); 5620 5621 // Build a compound literal constructing a value of the transparent 5622 // union type from this initializer list. 5623 TypeSourceInfo *unionTInfo = C.getTrivialTypeSourceInfo(UnionType); 5624 EResult = S.Owned( 5625 new (C) CompoundLiteralExpr(SourceLocation(), unionTInfo, UnionType, 5626 VK_RValue, Initializer, false)); 5627} 5628 5629Sema::AssignConvertType 5630Sema::CheckTransparentUnionArgumentConstraints(QualType ArgType, 5631 ExprResult &RHS) { 5632 QualType RHSType = RHS.get()->getType(); 5633 5634 // If the ArgType is a Union type, we want to handle a potential 5635 // transparent_union GCC extension. 5636 const RecordType *UT = ArgType->getAsUnionType(); 5637 if (!UT || !UT->getDecl()->hasAttr<TransparentUnionAttr>()) 5638 return Incompatible; 5639 5640 // The field to initialize within the transparent union. 5641 RecordDecl *UD = UT->getDecl(); 5642 FieldDecl *InitField = 0; 5643 // It's compatible if the expression matches any of the fields. 5644 for (RecordDecl::field_iterator it = UD->field_begin(), 5645 itend = UD->field_end(); 5646 it != itend; ++it) { 5647 if (it->getType()->isPointerType()) { 5648 // If the transparent union contains a pointer type, we allow: 5649 // 1) void pointer 5650 // 2) null pointer constant 5651 if (RHSType->isPointerType()) 5652 if (RHSType->castAs<PointerType>()->getPointeeType()->isVoidType()) { 5653 RHS = ImpCastExprToType(RHS.take(), it->getType(), CK_BitCast); 5654 InitField = *it; 5655 break; 5656 } 5657 5658 if (RHS.get()->isNullPointerConstant(Context, 5659 Expr::NPC_ValueDependentIsNull)) { 5660 RHS = ImpCastExprToType(RHS.take(), it->getType(), 5661 CK_NullToPointer); 5662 InitField = *it; 5663 break; 5664 } 5665 } 5666 5667 CastKind Kind = CK_Invalid; 5668 if (CheckAssignmentConstraints(it->getType(), RHS, Kind) 5669 == Compatible) { 5670 RHS = ImpCastExprToType(RHS.take(), it->getType(), Kind); 5671 InitField = *it; 5672 break; 5673 } 5674 } 5675 5676 if (!InitField) 5677 return Incompatible; 5678 5679 ConstructTransparentUnion(*this, Context, RHS, ArgType, InitField); 5680 return Compatible; 5681} 5682 5683Sema::AssignConvertType 5684Sema::CheckSingleAssignmentConstraints(QualType LHSType, ExprResult &RHS, 5685 bool Diagnose) { 5686 if (getLangOptions().CPlusPlus) { 5687 if (!LHSType->isRecordType() && !LHSType->isAtomicType()) { 5688 // C++ 5.17p3: If the left operand is not of class type, the 5689 // expression is implicitly converted (C++ 4) to the 5690 // cv-unqualified type of the left operand. 5691 ExprResult Res; 5692 if (Diagnose) { 5693 Res = PerformImplicitConversion(RHS.get(), LHSType.getUnqualifiedType(), 5694 AA_Assigning); 5695 } else { 5696 ImplicitConversionSequence ICS = 5697 TryImplicitConversion(RHS.get(), LHSType.getUnqualifiedType(), 5698 /*SuppressUserConversions=*/false, 5699 /*AllowExplicit=*/false, 5700 /*InOverloadResolution=*/false, 5701 /*CStyle=*/false, 5702 /*AllowObjCWritebackConversion=*/false); 5703 if (ICS.isFailure()) 5704 return Incompatible; 5705 Res = PerformImplicitConversion(RHS.get(), LHSType.getUnqualifiedType(), 5706 ICS, AA_Assigning); 5707 } 5708 if (Res.isInvalid()) 5709 return Incompatible; 5710 Sema::AssignConvertType result = Compatible; 5711 if (getLangOptions().ObjCAutoRefCount && 5712 !CheckObjCARCUnavailableWeakConversion(LHSType, 5713 RHS.get()->getType())) 5714 result = IncompatibleObjCWeakRef; 5715 RHS = move(Res); 5716 return result; 5717 } 5718 5719 // FIXME: Currently, we fall through and treat C++ classes like C 5720 // structures. 5721 // FIXME: We also fall through for atomics; not sure what should 5722 // happen there, though. 5723 } 5724 5725 // C99 6.5.16.1p1: the left operand is a pointer and the right is 5726 // a null pointer constant. 5727 if ((LHSType->isPointerType() || 5728 LHSType->isObjCObjectPointerType() || 5729 LHSType->isBlockPointerType()) 5730 && RHS.get()->isNullPointerConstant(Context, 5731 Expr::NPC_ValueDependentIsNull)) { 5732 RHS = ImpCastExprToType(RHS.take(), LHSType, CK_NullToPointer); 5733 return Compatible; 5734 } 5735 5736 // This check seems unnatural, however it is necessary to ensure the proper 5737 // conversion of functions/arrays. If the conversion were done for all 5738 // DeclExpr's (created by ActOnIdExpression), it would mess up the unary 5739 // expressions that suppress this implicit conversion (&, sizeof). 5740 // 5741 // Suppress this for references: C++ 8.5.3p5. 5742 if (!LHSType->isReferenceType()) { 5743 RHS = DefaultFunctionArrayLvalueConversion(RHS.take()); 5744 if (RHS.isInvalid()) 5745 return Incompatible; 5746 } 5747 5748 CastKind Kind = CK_Invalid; 5749 Sema::AssignConvertType result = 5750 CheckAssignmentConstraints(LHSType, RHS, Kind); 5751 5752 // C99 6.5.16.1p2: The value of the right operand is converted to the 5753 // type of the assignment expression. 5754 // CheckAssignmentConstraints allows the left-hand side to be a reference, 5755 // so that we can use references in built-in functions even in C. 5756 // The getNonReferenceType() call makes sure that the resulting expression 5757 // does not have reference type. 5758 if (result != Incompatible && RHS.get()->getType() != LHSType) 5759 RHS = ImpCastExprToType(RHS.take(), 5760 LHSType.getNonLValueExprType(Context), Kind); 5761 return result; 5762} 5763 5764QualType Sema::InvalidOperands(SourceLocation Loc, ExprResult &LHS, 5765 ExprResult &RHS) { 5766 Diag(Loc, diag::err_typecheck_invalid_operands) 5767 << LHS.get()->getType() << RHS.get()->getType() 5768 << LHS.get()->getSourceRange() << RHS.get()->getSourceRange(); 5769 return QualType(); 5770} 5771 5772QualType Sema::CheckVectorOperands(ExprResult &LHS, ExprResult &RHS, 5773 SourceLocation Loc, bool IsCompAssign) { 5774 if (!IsCompAssign) { 5775 LHS = DefaultFunctionArrayLvalueConversion(LHS.take()); 5776 if (LHS.isInvalid()) 5777 return QualType(); 5778 } 5779 RHS = DefaultFunctionArrayLvalueConversion(RHS.take()); 5780 if (RHS.isInvalid()) 5781 return QualType(); 5782 5783 // For conversion purposes, we ignore any qualifiers. 5784 // For example, "const float" and "float" are equivalent. 5785 QualType LHSType = 5786 Context.getCanonicalType(LHS.get()->getType()).getUnqualifiedType(); 5787 QualType RHSType = 5788 Context.getCanonicalType(RHS.get()->getType()).getUnqualifiedType(); 5789 5790 // If the vector types are identical, return. 5791 if (LHSType == RHSType) 5792 return LHSType; 5793 5794 // Handle the case of equivalent AltiVec and GCC vector types 5795 if (LHSType->isVectorType() && RHSType->isVectorType() && 5796 Context.areCompatibleVectorTypes(LHSType, RHSType)) { 5797 if (LHSType->isExtVectorType()) { 5798 RHS = ImpCastExprToType(RHS.take(), LHSType, CK_BitCast); 5799 return LHSType; 5800 } 5801 5802 if (!IsCompAssign) 5803 LHS = ImpCastExprToType(LHS.take(), RHSType, CK_BitCast); 5804 return RHSType; 5805 } 5806 5807 if (getLangOptions().LaxVectorConversions && 5808 Context.getTypeSize(LHSType) == Context.getTypeSize(RHSType)) { 5809 // If we are allowing lax vector conversions, and LHS and RHS are both 5810 // vectors, the total size only needs to be the same. This is a 5811 // bitcast; no bits are changed but the result type is different. 5812 // FIXME: Should we really be allowing this? 5813 RHS = ImpCastExprToType(RHS.take(), LHSType, CK_BitCast); 5814 return LHSType; 5815 } 5816 5817 // Canonicalize the ExtVector to the LHS, remember if we swapped so we can 5818 // swap back (so that we don't reverse the inputs to a subtract, for instance. 5819 bool swapped = false; 5820 if (RHSType->isExtVectorType() && !IsCompAssign) { 5821 swapped = true; 5822 std::swap(RHS, LHS); 5823 std::swap(RHSType, LHSType); 5824 } 5825 5826 // Handle the case of an ext vector and scalar. 5827 if (const ExtVectorType *LV = LHSType->getAs<ExtVectorType>()) { 5828 QualType EltTy = LV->getElementType(); 5829 if (EltTy->isIntegralType(Context) && RHSType->isIntegralType(Context)) { 5830 int order = Context.getIntegerTypeOrder(EltTy, RHSType); 5831 if (order > 0) 5832 RHS = ImpCastExprToType(RHS.take(), EltTy, CK_IntegralCast); 5833 if (order >= 0) { 5834 RHS = ImpCastExprToType(RHS.take(), LHSType, CK_VectorSplat); 5835 if (swapped) std::swap(RHS, LHS); 5836 return LHSType; 5837 } 5838 } 5839 if (EltTy->isRealFloatingType() && RHSType->isScalarType() && 5840 RHSType->isRealFloatingType()) { 5841 int order = Context.getFloatingTypeOrder(EltTy, RHSType); 5842 if (order > 0) 5843 RHS = ImpCastExprToType(RHS.take(), EltTy, CK_FloatingCast); 5844 if (order >= 0) { 5845 RHS = ImpCastExprToType(RHS.take(), LHSType, CK_VectorSplat); 5846 if (swapped) std::swap(RHS, LHS); 5847 return LHSType; 5848 } 5849 } 5850 } 5851 5852 // Vectors of different size or scalar and non-ext-vector are errors. 5853 if (swapped) std::swap(RHS, LHS); 5854 Diag(Loc, diag::err_typecheck_vector_not_convertable) 5855 << LHS.get()->getType() << RHS.get()->getType() 5856 << LHS.get()->getSourceRange() << RHS.get()->getSourceRange(); 5857 return QualType(); 5858} 5859 5860// checkArithmeticNull - Detect when a NULL constant is used improperly in an 5861// expression. These are mainly cases where the null pointer is used as an 5862// integer instead of a pointer. 5863static void checkArithmeticNull(Sema &S, ExprResult &LHS, ExprResult &RHS, 5864 SourceLocation Loc, bool IsCompare) { 5865 // The canonical way to check for a GNU null is with isNullPointerConstant, 5866 // but we use a bit of a hack here for speed; this is a relatively 5867 // hot path, and isNullPointerConstant is slow. 5868 bool LHSNull = isa<GNUNullExpr>(LHS.get()->IgnoreParenImpCasts()); 5869 bool RHSNull = isa<GNUNullExpr>(RHS.get()->IgnoreParenImpCasts()); 5870 5871 QualType NonNullType = LHSNull ? RHS.get()->getType() : LHS.get()->getType(); 5872 5873 // Avoid analyzing cases where the result will either be invalid (and 5874 // diagnosed as such) or entirely valid and not something to warn about. 5875 if ((!LHSNull && !RHSNull) || NonNullType->isBlockPointerType() || 5876 NonNullType->isMemberPointerType() || NonNullType->isFunctionType()) 5877 return; 5878 5879 // Comparison operations would not make sense with a null pointer no matter 5880 // what the other expression is. 5881 if (!IsCompare) { 5882 S.Diag(Loc, diag::warn_null_in_arithmetic_operation) 5883 << (LHSNull ? LHS.get()->getSourceRange() : SourceRange()) 5884 << (RHSNull ? RHS.get()->getSourceRange() : SourceRange()); 5885 return; 5886 } 5887 5888 // The rest of the operations only make sense with a null pointer 5889 // if the other expression is a pointer. 5890 if (LHSNull == RHSNull || NonNullType->isAnyPointerType() || 5891 NonNullType->canDecayToPointerType()) 5892 return; 5893 5894 S.Diag(Loc, diag::warn_null_in_comparison_operation) 5895 << LHSNull /* LHS is NULL */ << NonNullType 5896 << LHS.get()->getSourceRange() << RHS.get()->getSourceRange(); 5897} 5898 5899QualType Sema::CheckMultiplyDivideOperands(ExprResult &LHS, ExprResult &RHS, 5900 SourceLocation Loc, 5901 bool IsCompAssign, bool IsDiv) { 5902 checkArithmeticNull(*this, LHS, RHS, Loc, /*isCompare=*/false); 5903 5904 if (LHS.get()->getType()->isVectorType() || 5905 RHS.get()->getType()->isVectorType()) 5906 return CheckVectorOperands(LHS, RHS, Loc, IsCompAssign); 5907 5908 QualType compType = UsualArithmeticConversions(LHS, RHS, IsCompAssign); 5909 if (LHS.isInvalid() || RHS.isInvalid()) 5910 return QualType(); 5911 5912 if (!LHS.get()->getType()->isArithmeticType() || 5913 !RHS.get()->getType()->isArithmeticType()) 5914 return InvalidOperands(Loc, LHS, RHS); 5915 5916 // Check for division by zero. 5917 if (IsDiv && 5918 RHS.get()->isNullPointerConstant(Context, 5919 Expr::NPC_ValueDependentIsNotNull)) 5920 DiagRuntimeBehavior(Loc, RHS.get(), PDiag(diag::warn_division_by_zero) 5921 << RHS.get()->getSourceRange()); 5922 5923 return compType; 5924} 5925 5926QualType Sema::CheckRemainderOperands( 5927 ExprResult &LHS, ExprResult &RHS, SourceLocation Loc, bool IsCompAssign) { 5928 checkArithmeticNull(*this, LHS, RHS, Loc, /*isCompare=*/false); 5929 5930 if (LHS.get()->getType()->isVectorType() || 5931 RHS.get()->getType()->isVectorType()) { 5932 if (LHS.get()->getType()->hasIntegerRepresentation() && 5933 RHS.get()->getType()->hasIntegerRepresentation()) 5934 return CheckVectorOperands(LHS, RHS, Loc, IsCompAssign); 5935 return InvalidOperands(Loc, LHS, RHS); 5936 } 5937 5938 QualType compType = UsualArithmeticConversions(LHS, RHS, IsCompAssign); 5939 if (LHS.isInvalid() || RHS.isInvalid()) 5940 return QualType(); 5941 5942 if (!LHS.get()->getType()->isIntegerType() || 5943 !RHS.get()->getType()->isIntegerType()) 5944 return InvalidOperands(Loc, LHS, RHS); 5945 5946 // Check for remainder by zero. 5947 if (RHS.get()->isNullPointerConstant(Context, 5948 Expr::NPC_ValueDependentIsNotNull)) 5949 DiagRuntimeBehavior(Loc, RHS.get(), PDiag(diag::warn_remainder_by_zero) 5950 << RHS.get()->getSourceRange()); 5951 5952 return compType; 5953} 5954 5955/// \brief Diagnose invalid arithmetic on two void pointers. 5956static void diagnoseArithmeticOnTwoVoidPointers(Sema &S, SourceLocation Loc, 5957 Expr *LHSExpr, Expr *RHSExpr) { 5958 S.Diag(Loc, S.getLangOptions().CPlusPlus 5959 ? diag::err_typecheck_pointer_arith_void_type 5960 : diag::ext_gnu_void_ptr) 5961 << 1 /* two pointers */ << LHSExpr->getSourceRange() 5962 << RHSExpr->getSourceRange(); 5963} 5964 5965/// \brief Diagnose invalid arithmetic on a void pointer. 5966static void diagnoseArithmeticOnVoidPointer(Sema &S, SourceLocation Loc, 5967 Expr *Pointer) { 5968 S.Diag(Loc, S.getLangOptions().CPlusPlus 5969 ? diag::err_typecheck_pointer_arith_void_type 5970 : diag::ext_gnu_void_ptr) 5971 << 0 /* one pointer */ << Pointer->getSourceRange(); 5972} 5973 5974/// \brief Diagnose invalid arithmetic on two function pointers. 5975static void diagnoseArithmeticOnTwoFunctionPointers(Sema &S, SourceLocation Loc, 5976 Expr *LHS, Expr *RHS) { 5977 assert(LHS->getType()->isAnyPointerType()); 5978 assert(RHS->getType()->isAnyPointerType()); 5979 S.Diag(Loc, S.getLangOptions().CPlusPlus 5980 ? diag::err_typecheck_pointer_arith_function_type 5981 : diag::ext_gnu_ptr_func_arith) 5982 << 1 /* two pointers */ << LHS->getType()->getPointeeType() 5983 // We only show the second type if it differs from the first. 5984 << (unsigned)!S.Context.hasSameUnqualifiedType(LHS->getType(), 5985 RHS->getType()) 5986 << RHS->getType()->getPointeeType() 5987 << LHS->getSourceRange() << RHS->getSourceRange(); 5988} 5989 5990/// \brief Diagnose invalid arithmetic on a function pointer. 5991static void diagnoseArithmeticOnFunctionPointer(Sema &S, SourceLocation Loc, 5992 Expr *Pointer) { 5993 assert(Pointer->getType()->isAnyPointerType()); 5994 S.Diag(Loc, S.getLangOptions().CPlusPlus 5995 ? diag::err_typecheck_pointer_arith_function_type 5996 : diag::ext_gnu_ptr_func_arith) 5997 << 0 /* one pointer */ << Pointer->getType()->getPointeeType() 5998 << 0 /* one pointer, so only one type */ 5999 << Pointer->getSourceRange(); 6000} 6001 6002/// \brief Emit error if Operand is incomplete pointer type 6003/// 6004/// \returns True if pointer has incomplete type 6005static bool checkArithmeticIncompletePointerType(Sema &S, SourceLocation Loc, 6006 Expr *Operand) { 6007 if ((Operand->getType()->isPointerType() && 6008 !Operand->getType()->isDependentType()) || 6009 Operand->getType()->isObjCObjectPointerType()) { 6010 QualType PointeeTy = Operand->getType()->getPointeeType(); 6011 if (S.RequireCompleteType( 6012 Loc, PointeeTy, 6013 S.PDiag(diag::err_typecheck_arithmetic_incomplete_type) 6014 << PointeeTy << Operand->getSourceRange())) 6015 return true; 6016 } 6017 return false; 6018} 6019 6020/// \brief Check the validity of an arithmetic pointer operand. 6021/// 6022/// If the operand has pointer type, this code will check for pointer types 6023/// which are invalid in arithmetic operations. These will be diagnosed 6024/// appropriately, including whether or not the use is supported as an 6025/// extension. 6026/// 6027/// \returns True when the operand is valid to use (even if as an extension). 6028static bool checkArithmeticOpPointerOperand(Sema &S, SourceLocation Loc, 6029 Expr *Operand) { 6030 if (!Operand->getType()->isAnyPointerType()) return true; 6031 6032 QualType PointeeTy = Operand->getType()->getPointeeType(); 6033 if (PointeeTy->isVoidType()) { 6034 diagnoseArithmeticOnVoidPointer(S, Loc, Operand); 6035 return !S.getLangOptions().CPlusPlus; 6036 } 6037 if (PointeeTy->isFunctionType()) { 6038 diagnoseArithmeticOnFunctionPointer(S, Loc, Operand); 6039 return !S.getLangOptions().CPlusPlus; 6040 } 6041 6042 if (checkArithmeticIncompletePointerType(S, Loc, Operand)) return false; 6043 6044 return true; 6045} 6046 6047/// \brief Check the validity of a binary arithmetic operation w.r.t. pointer 6048/// operands. 6049/// 6050/// This routine will diagnose any invalid arithmetic on pointer operands much 6051/// like \see checkArithmeticOpPointerOperand. However, it has special logic 6052/// for emitting a single diagnostic even for operations where both LHS and RHS 6053/// are (potentially problematic) pointers. 6054/// 6055/// \returns True when the operand is valid to use (even if as an extension). 6056static bool checkArithmeticBinOpPointerOperands(Sema &S, SourceLocation Loc, 6057 Expr *LHSExpr, Expr *RHSExpr) { 6058 bool isLHSPointer = LHSExpr->getType()->isAnyPointerType(); 6059 bool isRHSPointer = RHSExpr->getType()->isAnyPointerType(); 6060 if (!isLHSPointer && !isRHSPointer) return true; 6061 6062 QualType LHSPointeeTy, RHSPointeeTy; 6063 if (isLHSPointer) LHSPointeeTy = LHSExpr->getType()->getPointeeType(); 6064 if (isRHSPointer) RHSPointeeTy = RHSExpr->getType()->getPointeeType(); 6065 6066 // Check for arithmetic on pointers to incomplete types. 6067 bool isLHSVoidPtr = isLHSPointer && LHSPointeeTy->isVoidType(); 6068 bool isRHSVoidPtr = isRHSPointer && RHSPointeeTy->isVoidType(); 6069 if (isLHSVoidPtr || isRHSVoidPtr) { 6070 if (!isRHSVoidPtr) diagnoseArithmeticOnVoidPointer(S, Loc, LHSExpr); 6071 else if (!isLHSVoidPtr) diagnoseArithmeticOnVoidPointer(S, Loc, RHSExpr); 6072 else diagnoseArithmeticOnTwoVoidPointers(S, Loc, LHSExpr, RHSExpr); 6073 6074 return !S.getLangOptions().CPlusPlus; 6075 } 6076 6077 bool isLHSFuncPtr = isLHSPointer && LHSPointeeTy->isFunctionType(); 6078 bool isRHSFuncPtr = isRHSPointer && RHSPointeeTy->isFunctionType(); 6079 if (isLHSFuncPtr || isRHSFuncPtr) { 6080 if (!isRHSFuncPtr) diagnoseArithmeticOnFunctionPointer(S, Loc, LHSExpr); 6081 else if (!isLHSFuncPtr) diagnoseArithmeticOnFunctionPointer(S, Loc, 6082 RHSExpr); 6083 else diagnoseArithmeticOnTwoFunctionPointers(S, Loc, LHSExpr, RHSExpr); 6084 6085 return !S.getLangOptions().CPlusPlus; 6086 } 6087 6088 if (checkArithmeticIncompletePointerType(S, Loc, LHSExpr)) return false; 6089 if (checkArithmeticIncompletePointerType(S, Loc, RHSExpr)) return false; 6090 6091 return true; 6092} 6093 6094/// \brief Check bad cases where we step over interface counts. 6095static bool checkArithmethicPointerOnNonFragileABI(Sema &S, 6096 SourceLocation OpLoc, 6097 Expr *Op) { 6098 assert(Op->getType()->isAnyPointerType()); 6099 QualType PointeeTy = Op->getType()->getPointeeType(); 6100 if (!PointeeTy->isObjCObjectType() || !S.LangOpts.ObjCNonFragileABI) 6101 return true; 6102 6103 S.Diag(OpLoc, diag::err_arithmetic_nonfragile_interface) 6104 << PointeeTy << Op->getSourceRange(); 6105 return false; 6106} 6107 6108/// \brief Emit error when two pointers are incompatible. 6109static void diagnosePointerIncompatibility(Sema &S, SourceLocation Loc, 6110 Expr *LHSExpr, Expr *RHSExpr) { 6111 assert(LHSExpr->getType()->isAnyPointerType()); 6112 assert(RHSExpr->getType()->isAnyPointerType()); 6113 S.Diag(Loc, diag::err_typecheck_sub_ptr_compatible) 6114 << LHSExpr->getType() << RHSExpr->getType() << LHSExpr->getSourceRange() 6115 << RHSExpr->getSourceRange(); 6116} 6117 6118QualType Sema::CheckAdditionOperands( // C99 6.5.6 6119 ExprResult &LHS, ExprResult &RHS, SourceLocation Loc, QualType* CompLHSTy) { 6120 checkArithmeticNull(*this, LHS, RHS, Loc, /*isCompare=*/false); 6121 6122 if (LHS.get()->getType()->isVectorType() || 6123 RHS.get()->getType()->isVectorType()) { 6124 QualType compType = CheckVectorOperands(LHS, RHS, Loc, CompLHSTy); 6125 if (CompLHSTy) *CompLHSTy = compType; 6126 return compType; 6127 } 6128 6129 QualType compType = UsualArithmeticConversions(LHS, RHS, CompLHSTy); 6130 if (LHS.isInvalid() || RHS.isInvalid()) 6131 return QualType(); 6132 6133 // handle the common case first (both operands are arithmetic). 6134 if (LHS.get()->getType()->isArithmeticType() && 6135 RHS.get()->getType()->isArithmeticType()) { 6136 if (CompLHSTy) *CompLHSTy = compType; 6137 return compType; 6138 } 6139 6140 // Put any potential pointer into PExp 6141 Expr* PExp = LHS.get(), *IExp = RHS.get(); 6142 if (IExp->getType()->isAnyPointerType()) 6143 std::swap(PExp, IExp); 6144 6145 if (!PExp->getType()->isAnyPointerType()) 6146 return InvalidOperands(Loc, LHS, RHS); 6147 6148 if (!IExp->getType()->isIntegerType()) 6149 return InvalidOperands(Loc, LHS, RHS); 6150 6151 if (!checkArithmeticOpPointerOperand(*this, Loc, PExp)) 6152 return QualType(); 6153 6154 // Diagnose bad cases where we step over interface counts. 6155 if (!checkArithmethicPointerOnNonFragileABI(*this, Loc, PExp)) 6156 return QualType(); 6157 6158 // Check array bounds for pointer arithemtic 6159 CheckArrayAccess(PExp, IExp); 6160 6161 if (CompLHSTy) { 6162 QualType LHSTy = Context.isPromotableBitField(LHS.get()); 6163 if (LHSTy.isNull()) { 6164 LHSTy = LHS.get()->getType(); 6165 if (LHSTy->isPromotableIntegerType()) 6166 LHSTy = Context.getPromotedIntegerType(LHSTy); 6167 } 6168 *CompLHSTy = LHSTy; 6169 } 6170 6171 return PExp->getType(); 6172} 6173 6174// C99 6.5.6 6175QualType Sema::CheckSubtractionOperands(ExprResult &LHS, ExprResult &RHS, 6176 SourceLocation Loc, 6177 QualType* CompLHSTy) { 6178 checkArithmeticNull(*this, LHS, RHS, Loc, /*isCompare=*/false); 6179 6180 if (LHS.get()->getType()->isVectorType() || 6181 RHS.get()->getType()->isVectorType()) { 6182 QualType compType = CheckVectorOperands(LHS, RHS, Loc, CompLHSTy); 6183 if (CompLHSTy) *CompLHSTy = compType; 6184 return compType; 6185 } 6186 6187 QualType compType = UsualArithmeticConversions(LHS, RHS, CompLHSTy); 6188 if (LHS.isInvalid() || RHS.isInvalid()) 6189 return QualType(); 6190 6191 // Enforce type constraints: C99 6.5.6p3. 6192 6193 // Handle the common case first (both operands are arithmetic). 6194 if (LHS.get()->getType()->isArithmeticType() && 6195 RHS.get()->getType()->isArithmeticType()) { 6196 if (CompLHSTy) *CompLHSTy = compType; 6197 return compType; 6198 } 6199 6200 // Either ptr - int or ptr - ptr. 6201 if (LHS.get()->getType()->isAnyPointerType()) { 6202 QualType lpointee = LHS.get()->getType()->getPointeeType(); 6203 6204 // Diagnose bad cases where we step over interface counts. 6205 if (!checkArithmethicPointerOnNonFragileABI(*this, Loc, LHS.get())) 6206 return QualType(); 6207 6208 // The result type of a pointer-int computation is the pointer type. 6209 if (RHS.get()->getType()->isIntegerType()) { 6210 if (!checkArithmeticOpPointerOperand(*this, Loc, LHS.get())) 6211 return QualType(); 6212 6213 // Check array bounds for pointer arithemtic 6214 CheckArrayAccess(LHS.get(), RHS.get(), /*ArraySubscriptExpr*/0, 6215 /*AllowOnePastEnd*/true, /*IndexNegated*/true); 6216 6217 if (CompLHSTy) *CompLHSTy = LHS.get()->getType(); 6218 return LHS.get()->getType(); 6219 } 6220 6221 // Handle pointer-pointer subtractions. 6222 if (const PointerType *RHSPTy 6223 = RHS.get()->getType()->getAs<PointerType>()) { 6224 QualType rpointee = RHSPTy->getPointeeType(); 6225 6226 if (getLangOptions().CPlusPlus) { 6227 // Pointee types must be the same: C++ [expr.add] 6228 if (!Context.hasSameUnqualifiedType(lpointee, rpointee)) { 6229 diagnosePointerIncompatibility(*this, Loc, LHS.get(), RHS.get()); 6230 } 6231 } else { 6232 // Pointee types must be compatible C99 6.5.6p3 6233 if (!Context.typesAreCompatible( 6234 Context.getCanonicalType(lpointee).getUnqualifiedType(), 6235 Context.getCanonicalType(rpointee).getUnqualifiedType())) { 6236 diagnosePointerIncompatibility(*this, Loc, LHS.get(), RHS.get()); 6237 return QualType(); 6238 } 6239 } 6240 6241 if (!checkArithmeticBinOpPointerOperands(*this, Loc, 6242 LHS.get(), RHS.get())) 6243 return QualType(); 6244 6245 if (CompLHSTy) *CompLHSTy = LHS.get()->getType(); 6246 return Context.getPointerDiffType(); 6247 } 6248 } 6249 6250 return InvalidOperands(Loc, LHS, RHS); 6251} 6252 6253static bool isScopedEnumerationType(QualType T) { 6254 if (const EnumType *ET = dyn_cast<EnumType>(T)) 6255 return ET->getDecl()->isScoped(); 6256 return false; 6257} 6258 6259static void DiagnoseBadShiftValues(Sema& S, ExprResult &LHS, ExprResult &RHS, 6260 SourceLocation Loc, unsigned Opc, 6261 QualType LHSType) { 6262 llvm::APSInt Right; 6263 // Check right/shifter operand 6264 if (RHS.get()->isValueDependent() || 6265 !RHS.get()->isIntegerConstantExpr(Right, S.Context)) 6266 return; 6267 6268 if (Right.isNegative()) { 6269 S.DiagRuntimeBehavior(Loc, RHS.get(), 6270 S.PDiag(diag::warn_shift_negative) 6271 << RHS.get()->getSourceRange()); 6272 return; 6273 } 6274 llvm::APInt LeftBits(Right.getBitWidth(), 6275 S.Context.getTypeSize(LHS.get()->getType())); 6276 if (Right.uge(LeftBits)) { 6277 S.DiagRuntimeBehavior(Loc, RHS.get(), 6278 S.PDiag(diag::warn_shift_gt_typewidth) 6279 << RHS.get()->getSourceRange()); 6280 return; 6281 } 6282 if (Opc != BO_Shl) 6283 return; 6284 6285 // When left shifting an ICE which is signed, we can check for overflow which 6286 // according to C++ has undefined behavior ([expr.shift] 5.8/2). Unsigned 6287 // integers have defined behavior modulo one more than the maximum value 6288 // representable in the result type, so never warn for those. 6289 llvm::APSInt Left; 6290 if (LHS.get()->isValueDependent() || 6291 !LHS.get()->isIntegerConstantExpr(Left, S.Context) || 6292 LHSType->hasUnsignedIntegerRepresentation()) 6293 return; 6294 llvm::APInt ResultBits = 6295 static_cast<llvm::APInt&>(Right) + Left.getMinSignedBits(); 6296 if (LeftBits.uge(ResultBits)) 6297 return; 6298 llvm::APSInt Result = Left.extend(ResultBits.getLimitedValue()); 6299 Result = Result.shl(Right); 6300 6301 // Print the bit representation of the signed integer as an unsigned 6302 // hexadecimal number. 6303 llvm::SmallString<40> HexResult; 6304 Result.toString(HexResult, 16, /*Signed =*/false, /*Literal =*/true); 6305 6306 // If we are only missing a sign bit, this is less likely to result in actual 6307 // bugs -- if the result is cast back to an unsigned type, it will have the 6308 // expected value. Thus we place this behind a different warning that can be 6309 // turned off separately if needed. 6310 if (LeftBits == ResultBits - 1) { 6311 S.Diag(Loc, diag::warn_shift_result_sets_sign_bit) 6312 << HexResult.str() << LHSType 6313 << LHS.get()->getSourceRange() << RHS.get()->getSourceRange(); 6314 return; 6315 } 6316 6317 S.Diag(Loc, diag::warn_shift_result_gt_typewidth) 6318 << HexResult.str() << Result.getMinSignedBits() << LHSType 6319 << Left.getBitWidth() << LHS.get()->getSourceRange() 6320 << RHS.get()->getSourceRange(); 6321} 6322 6323// C99 6.5.7 6324QualType Sema::CheckShiftOperands(ExprResult &LHS, ExprResult &RHS, 6325 SourceLocation Loc, unsigned Opc, 6326 bool IsCompAssign) { 6327 checkArithmeticNull(*this, LHS, RHS, Loc, /*isCompare=*/false); 6328 6329 // C99 6.5.7p2: Each of the operands shall have integer type. 6330 if (!LHS.get()->getType()->hasIntegerRepresentation() || 6331 !RHS.get()->getType()->hasIntegerRepresentation()) 6332 return InvalidOperands(Loc, LHS, RHS); 6333 6334 // C++0x: Don't allow scoped enums. FIXME: Use something better than 6335 // hasIntegerRepresentation() above instead of this. 6336 if (isScopedEnumerationType(LHS.get()->getType()) || 6337 isScopedEnumerationType(RHS.get()->getType())) { 6338 return InvalidOperands(Loc, LHS, RHS); 6339 } 6340 6341 // Vector shifts promote their scalar inputs to vector type. 6342 if (LHS.get()->getType()->isVectorType() || 6343 RHS.get()->getType()->isVectorType()) 6344 return CheckVectorOperands(LHS, RHS, Loc, IsCompAssign); 6345 6346 // Shifts don't perform usual arithmetic conversions, they just do integer 6347 // promotions on each operand. C99 6.5.7p3 6348 6349 // For the LHS, do usual unary conversions, but then reset them away 6350 // if this is a compound assignment. 6351 ExprResult OldLHS = LHS; 6352 LHS = UsualUnaryConversions(LHS.take()); 6353 if (LHS.isInvalid()) 6354 return QualType(); 6355 QualType LHSType = LHS.get()->getType(); 6356 if (IsCompAssign) LHS = OldLHS; 6357 6358 // The RHS is simpler. 6359 RHS = UsualUnaryConversions(RHS.take()); 6360 if (RHS.isInvalid()) 6361 return QualType(); 6362 6363 // Sanity-check shift operands 6364 DiagnoseBadShiftValues(*this, LHS, RHS, Loc, Opc, LHSType); 6365 6366 // "The type of the result is that of the promoted left operand." 6367 return LHSType; 6368} 6369 6370static bool IsWithinTemplateSpecialization(Decl *D) { 6371 if (DeclContext *DC = D->getDeclContext()) { 6372 if (isa<ClassTemplateSpecializationDecl>(DC)) 6373 return true; 6374 if (FunctionDecl *FD = dyn_cast<FunctionDecl>(DC)) 6375 return FD->isFunctionTemplateSpecialization(); 6376 } 6377 return false; 6378} 6379 6380/// If two different enums are compared, raise a warning. 6381static void checkEnumComparison(Sema &S, SourceLocation Loc, ExprResult &LHS, 6382 ExprResult &RHS) { 6383 QualType LHSStrippedType = LHS.get()->IgnoreParenImpCasts()->getType(); 6384 QualType RHSStrippedType = RHS.get()->IgnoreParenImpCasts()->getType(); 6385 6386 const EnumType *LHSEnumType = LHSStrippedType->getAs<EnumType>(); 6387 if (!LHSEnumType) 6388 return; 6389 const EnumType *RHSEnumType = RHSStrippedType->getAs<EnumType>(); 6390 if (!RHSEnumType) 6391 return; 6392 6393 // Ignore anonymous enums. 6394 if (!LHSEnumType->getDecl()->getIdentifier()) 6395 return; 6396 if (!RHSEnumType->getDecl()->getIdentifier()) 6397 return; 6398 6399 if (S.Context.hasSameUnqualifiedType(LHSStrippedType, RHSStrippedType)) 6400 return; 6401 6402 S.Diag(Loc, diag::warn_comparison_of_mixed_enum_types) 6403 << LHSStrippedType << RHSStrippedType 6404 << LHS.get()->getSourceRange() << RHS.get()->getSourceRange(); 6405} 6406 6407/// \brief Diagnose bad pointer comparisons. 6408static void diagnoseDistinctPointerComparison(Sema &S, SourceLocation Loc, 6409 ExprResult &LHS, ExprResult &RHS, 6410 bool IsError) { 6411 S.Diag(Loc, IsError ? diag::err_typecheck_comparison_of_distinct_pointers 6412 : diag::ext_typecheck_comparison_of_distinct_pointers) 6413 << LHS.get()->getType() << RHS.get()->getType() 6414 << LHS.get()->getSourceRange() << RHS.get()->getSourceRange(); 6415} 6416 6417/// \brief Returns false if the pointers are converted to a composite type, 6418/// true otherwise. 6419static bool convertPointersToCompositeType(Sema &S, SourceLocation Loc, 6420 ExprResult &LHS, ExprResult &RHS) { 6421 // C++ [expr.rel]p2: 6422 // [...] Pointer conversions (4.10) and qualification 6423 // conversions (4.4) are performed on pointer operands (or on 6424 // a pointer operand and a null pointer constant) to bring 6425 // them to their composite pointer type. [...] 6426 // 6427 // C++ [expr.eq]p1 uses the same notion for (in)equality 6428 // comparisons of pointers. 6429 6430 // C++ [expr.eq]p2: 6431 // In addition, pointers to members can be compared, or a pointer to 6432 // member and a null pointer constant. Pointer to member conversions 6433 // (4.11) and qualification conversions (4.4) are performed to bring 6434 // them to a common type. If one operand is a null pointer constant, 6435 // the common type is the type of the other operand. Otherwise, the 6436 // common type is a pointer to member type similar (4.4) to the type 6437 // of one of the operands, with a cv-qualification signature (4.4) 6438 // that is the union of the cv-qualification signatures of the operand 6439 // types. 6440 6441 QualType LHSType = LHS.get()->getType(); 6442 QualType RHSType = RHS.get()->getType(); 6443 assert((LHSType->isPointerType() && RHSType->isPointerType()) || 6444 (LHSType->isMemberPointerType() && RHSType->isMemberPointerType())); 6445 6446 bool NonStandardCompositeType = false; 6447 bool *BoolPtr = S.isSFINAEContext() ? 0 : &NonStandardCompositeType; 6448 QualType T = S.FindCompositePointerType(Loc, LHS, RHS, BoolPtr); 6449 if (T.isNull()) { 6450 diagnoseDistinctPointerComparison(S, Loc, LHS, RHS, /*isError*/true); 6451 return true; 6452 } 6453 6454 if (NonStandardCompositeType) 6455 S.Diag(Loc, diag::ext_typecheck_comparison_of_distinct_pointers_nonstandard) 6456 << LHSType << RHSType << T << LHS.get()->getSourceRange() 6457 << RHS.get()->getSourceRange(); 6458 6459 LHS = S.ImpCastExprToType(LHS.take(), T, CK_BitCast); 6460 RHS = S.ImpCastExprToType(RHS.take(), T, CK_BitCast); 6461 return false; 6462} 6463 6464static void diagnoseFunctionPointerToVoidComparison(Sema &S, SourceLocation Loc, 6465 ExprResult &LHS, 6466 ExprResult &RHS, 6467 bool IsError) { 6468 S.Diag(Loc, IsError ? diag::err_typecheck_comparison_of_fptr_to_void 6469 : diag::ext_typecheck_comparison_of_fptr_to_void) 6470 << LHS.get()->getType() << RHS.get()->getType() 6471 << LHS.get()->getSourceRange() << RHS.get()->getSourceRange(); 6472} 6473 6474// C99 6.5.8, C++ [expr.rel] 6475QualType Sema::CheckCompareOperands(ExprResult &LHS, ExprResult &RHS, 6476 SourceLocation Loc, unsigned OpaqueOpc, 6477 bool IsRelational) { 6478 checkArithmeticNull(*this, LHS, RHS, Loc, /*isCompare=*/true); 6479 6480 BinaryOperatorKind Opc = (BinaryOperatorKind) OpaqueOpc; 6481 6482 // Handle vector comparisons separately. 6483 if (LHS.get()->getType()->isVectorType() || 6484 RHS.get()->getType()->isVectorType()) 6485 return CheckVectorCompareOperands(LHS, RHS, Loc, IsRelational); 6486 6487 QualType LHSType = LHS.get()->getType(); 6488 QualType RHSType = RHS.get()->getType(); 6489 6490 Expr *LHSStripped = LHS.get()->IgnoreParenImpCasts(); 6491 Expr *RHSStripped = RHS.get()->IgnoreParenImpCasts(); 6492 6493 checkEnumComparison(*this, Loc, LHS, RHS); 6494 6495 if (!LHSType->hasFloatingRepresentation() && 6496 !(LHSType->isBlockPointerType() && IsRelational) && 6497 !LHS.get()->getLocStart().isMacroID() && 6498 !RHS.get()->getLocStart().isMacroID()) { 6499 // For non-floating point types, check for self-comparisons of the form 6500 // x == x, x != x, x < x, etc. These always evaluate to a constant, and 6501 // often indicate logic errors in the program. 6502 // 6503 // NOTE: Don't warn about comparison expressions resulting from macro 6504 // expansion. Also don't warn about comparisons which are only self 6505 // comparisons within a template specialization. The warnings should catch 6506 // obvious cases in the definition of the template anyways. The idea is to 6507 // warn when the typed comparison operator will always evaluate to the same 6508 // result. 6509 if (DeclRefExpr* DRL = dyn_cast<DeclRefExpr>(LHSStripped)) { 6510 if (DeclRefExpr* DRR = dyn_cast<DeclRefExpr>(RHSStripped)) { 6511 if (DRL->getDecl() == DRR->getDecl() && 6512 !IsWithinTemplateSpecialization(DRL->getDecl())) { 6513 DiagRuntimeBehavior(Loc, 0, PDiag(diag::warn_comparison_always) 6514 << 0 // self- 6515 << (Opc == BO_EQ 6516 || Opc == BO_LE 6517 || Opc == BO_GE)); 6518 } else if (LHSType->isArrayType() && RHSType->isArrayType() && 6519 !DRL->getDecl()->getType()->isReferenceType() && 6520 !DRR->getDecl()->getType()->isReferenceType()) { 6521 // what is it always going to eval to? 6522 char always_evals_to; 6523 switch(Opc) { 6524 case BO_EQ: // e.g. array1 == array2 6525 always_evals_to = 0; // false 6526 break; 6527 case BO_NE: // e.g. array1 != array2 6528 always_evals_to = 1; // true 6529 break; 6530 default: 6531 // best we can say is 'a constant' 6532 always_evals_to = 2; // e.g. array1 <= array2 6533 break; 6534 } 6535 DiagRuntimeBehavior(Loc, 0, PDiag(diag::warn_comparison_always) 6536 << 1 // array 6537 << always_evals_to); 6538 } 6539 } 6540 } 6541 6542 if (isa<CastExpr>(LHSStripped)) 6543 LHSStripped = LHSStripped->IgnoreParenCasts(); 6544 if (isa<CastExpr>(RHSStripped)) 6545 RHSStripped = RHSStripped->IgnoreParenCasts(); 6546 6547 // Warn about comparisons against a string constant (unless the other 6548 // operand is null), the user probably wants strcmp. 6549 Expr *literalString = 0; 6550 Expr *literalStringStripped = 0; 6551 if ((isa<StringLiteral>(LHSStripped) || isa<ObjCEncodeExpr>(LHSStripped)) && 6552 !RHSStripped->isNullPointerConstant(Context, 6553 Expr::NPC_ValueDependentIsNull)) { 6554 literalString = LHS.get(); 6555 literalStringStripped = LHSStripped; 6556 } else if ((isa<StringLiteral>(RHSStripped) || 6557 isa<ObjCEncodeExpr>(RHSStripped)) && 6558 !LHSStripped->isNullPointerConstant(Context, 6559 Expr::NPC_ValueDependentIsNull)) { 6560 literalString = RHS.get(); 6561 literalStringStripped = RHSStripped; 6562 } 6563 6564 if (literalString) { 6565 std::string resultComparison; 6566 switch (Opc) { 6567 case BO_LT: resultComparison = ") < 0"; break; 6568 case BO_GT: resultComparison = ") > 0"; break; 6569 case BO_LE: resultComparison = ") <= 0"; break; 6570 case BO_GE: resultComparison = ") >= 0"; break; 6571 case BO_EQ: resultComparison = ") == 0"; break; 6572 case BO_NE: resultComparison = ") != 0"; break; 6573 default: llvm_unreachable("Invalid comparison operator"); 6574 } 6575 6576 DiagRuntimeBehavior(Loc, 0, 6577 PDiag(diag::warn_stringcompare) 6578 << isa<ObjCEncodeExpr>(literalStringStripped) 6579 << literalString->getSourceRange()); 6580 } 6581 } 6582 6583 // C99 6.5.8p3 / C99 6.5.9p4 6584 if (LHS.get()->getType()->isArithmeticType() && 6585 RHS.get()->getType()->isArithmeticType()) { 6586 UsualArithmeticConversions(LHS, RHS); 6587 if (LHS.isInvalid() || RHS.isInvalid()) 6588 return QualType(); 6589 } 6590 else { 6591 LHS = UsualUnaryConversions(LHS.take()); 6592 if (LHS.isInvalid()) 6593 return QualType(); 6594 6595 RHS = UsualUnaryConversions(RHS.take()); 6596 if (RHS.isInvalid()) 6597 return QualType(); 6598 } 6599 6600 LHSType = LHS.get()->getType(); 6601 RHSType = RHS.get()->getType(); 6602 6603 // The result of comparisons is 'bool' in C++, 'int' in C. 6604 QualType ResultTy = Context.getLogicalOperationType(); 6605 6606 if (IsRelational) { 6607 if (LHSType->isRealType() && RHSType->isRealType()) 6608 return ResultTy; 6609 } else { 6610 // Check for comparisons of floating point operands using != and ==. 6611 if (LHSType->hasFloatingRepresentation()) 6612 CheckFloatComparison(Loc, LHS.get(), RHS.get()); 6613 6614 if (LHSType->isArithmeticType() && RHSType->isArithmeticType()) 6615 return ResultTy; 6616 } 6617 6618 bool LHSIsNull = LHS.get()->isNullPointerConstant(Context, 6619 Expr::NPC_ValueDependentIsNull); 6620 bool RHSIsNull = RHS.get()->isNullPointerConstant(Context, 6621 Expr::NPC_ValueDependentIsNull); 6622 6623 // All of the following pointer-related warnings are GCC extensions, except 6624 // when handling null pointer constants. 6625 if (LHSType->isPointerType() && RHSType->isPointerType()) { // C99 6.5.8p2 6626 QualType LCanPointeeTy = 6627 LHSType->castAs<PointerType>()->getPointeeType().getCanonicalType(); 6628 QualType RCanPointeeTy = 6629 RHSType->castAs<PointerType>()->getPointeeType().getCanonicalType(); 6630 6631 if (getLangOptions().CPlusPlus) { 6632 if (LCanPointeeTy == RCanPointeeTy) 6633 return ResultTy; 6634 if (!IsRelational && 6635 (LCanPointeeTy->isVoidType() || RCanPointeeTy->isVoidType())) { 6636 // Valid unless comparison between non-null pointer and function pointer 6637 // This is a gcc extension compatibility comparison. 6638 // In a SFINAE context, we treat this as a hard error to maintain 6639 // conformance with the C++ standard. 6640 if ((LCanPointeeTy->isFunctionType() || RCanPointeeTy->isFunctionType()) 6641 && !LHSIsNull && !RHSIsNull) { 6642 diagnoseFunctionPointerToVoidComparison( 6643 *this, Loc, LHS, RHS, /*isError*/ isSFINAEContext()); 6644 6645 if (isSFINAEContext()) 6646 return QualType(); 6647 6648 RHS = ImpCastExprToType(RHS.take(), LHSType, CK_BitCast); 6649 return ResultTy; 6650 } 6651 } 6652 6653 if (convertPointersToCompositeType(*this, Loc, LHS, RHS)) 6654 return QualType(); 6655 else 6656 return ResultTy; 6657 } 6658 // C99 6.5.9p2 and C99 6.5.8p2 6659 if (Context.typesAreCompatible(LCanPointeeTy.getUnqualifiedType(), 6660 RCanPointeeTy.getUnqualifiedType())) { 6661 // Valid unless a relational comparison of function pointers 6662 if (IsRelational && LCanPointeeTy->isFunctionType()) { 6663 Diag(Loc, diag::ext_typecheck_ordered_comparison_of_function_pointers) 6664 << LHSType << RHSType << LHS.get()->getSourceRange() 6665 << RHS.get()->getSourceRange(); 6666 } 6667 } else if (!IsRelational && 6668 (LCanPointeeTy->isVoidType() || RCanPointeeTy->isVoidType())) { 6669 // Valid unless comparison between non-null pointer and function pointer 6670 if ((LCanPointeeTy->isFunctionType() || RCanPointeeTy->isFunctionType()) 6671 && !LHSIsNull && !RHSIsNull) 6672 diagnoseFunctionPointerToVoidComparison(*this, Loc, LHS, RHS, 6673 /*isError*/false); 6674 } else { 6675 // Invalid 6676 diagnoseDistinctPointerComparison(*this, Loc, LHS, RHS, /*isError*/false); 6677 } 6678 if (LCanPointeeTy != RCanPointeeTy) { 6679 if (LHSIsNull && !RHSIsNull) 6680 LHS = ImpCastExprToType(LHS.take(), RHSType, CK_BitCast); 6681 else 6682 RHS = ImpCastExprToType(RHS.take(), LHSType, CK_BitCast); 6683 } 6684 return ResultTy; 6685 } 6686 6687 if (getLangOptions().CPlusPlus) { 6688 // Comparison of nullptr_t with itself. 6689 if (LHSType->isNullPtrType() && RHSType->isNullPtrType()) 6690 return ResultTy; 6691 6692 // Comparison of pointers with null pointer constants and equality 6693 // comparisons of member pointers to null pointer constants. 6694 if (RHSIsNull && 6695 ((LHSType->isAnyPointerType() || LHSType->isNullPtrType()) || 6696 (!IsRelational && 6697 (LHSType->isMemberPointerType() || LHSType->isBlockPointerType())))) { 6698 RHS = ImpCastExprToType(RHS.take(), LHSType, 6699 LHSType->isMemberPointerType() 6700 ? CK_NullToMemberPointer 6701 : CK_NullToPointer); 6702 return ResultTy; 6703 } 6704 if (LHSIsNull && 6705 ((RHSType->isAnyPointerType() || RHSType->isNullPtrType()) || 6706 (!IsRelational && 6707 (RHSType->isMemberPointerType() || RHSType->isBlockPointerType())))) { 6708 LHS = ImpCastExprToType(LHS.take(), RHSType, 6709 RHSType->isMemberPointerType() 6710 ? CK_NullToMemberPointer 6711 : CK_NullToPointer); 6712 return ResultTy; 6713 } 6714 6715 // Comparison of member pointers. 6716 if (!IsRelational && 6717 LHSType->isMemberPointerType() && RHSType->isMemberPointerType()) { 6718 if (convertPointersToCompositeType(*this, Loc, LHS, RHS)) 6719 return QualType(); 6720 else 6721 return ResultTy; 6722 } 6723 6724 // Handle scoped enumeration types specifically, since they don't promote 6725 // to integers. 6726 if (LHS.get()->getType()->isEnumeralType() && 6727 Context.hasSameUnqualifiedType(LHS.get()->getType(), 6728 RHS.get()->getType())) 6729 return ResultTy; 6730 } 6731 6732 // Handle block pointer types. 6733 if (!IsRelational && LHSType->isBlockPointerType() && 6734 RHSType->isBlockPointerType()) { 6735 QualType lpointee = LHSType->castAs<BlockPointerType>()->getPointeeType(); 6736 QualType rpointee = RHSType->castAs<BlockPointerType>()->getPointeeType(); 6737 6738 if (!LHSIsNull && !RHSIsNull && 6739 !Context.typesAreCompatible(lpointee, rpointee)) { 6740 Diag(Loc, diag::err_typecheck_comparison_of_distinct_blocks) 6741 << LHSType << RHSType << LHS.get()->getSourceRange() 6742 << RHS.get()->getSourceRange(); 6743 } 6744 RHS = ImpCastExprToType(RHS.take(), LHSType, CK_BitCast); 6745 return ResultTy; 6746 } 6747 6748 // Allow block pointers to be compared with null pointer constants. 6749 if (!IsRelational 6750 && ((LHSType->isBlockPointerType() && RHSType->isPointerType()) 6751 || (LHSType->isPointerType() && RHSType->isBlockPointerType()))) { 6752 if (!LHSIsNull && !RHSIsNull) { 6753 if (!((RHSType->isPointerType() && RHSType->castAs<PointerType>() 6754 ->getPointeeType()->isVoidType()) 6755 || (LHSType->isPointerType() && LHSType->castAs<PointerType>() 6756 ->getPointeeType()->isVoidType()))) 6757 Diag(Loc, diag::err_typecheck_comparison_of_distinct_blocks) 6758 << LHSType << RHSType << LHS.get()->getSourceRange() 6759 << RHS.get()->getSourceRange(); 6760 } 6761 if (LHSIsNull && !RHSIsNull) 6762 LHS = ImpCastExprToType(LHS.take(), RHSType, 6763 RHSType->isPointerType() ? CK_BitCast 6764 : CK_AnyPointerToBlockPointerCast); 6765 else 6766 RHS = ImpCastExprToType(RHS.take(), LHSType, 6767 LHSType->isPointerType() ? CK_BitCast 6768 : CK_AnyPointerToBlockPointerCast); 6769 return ResultTy; 6770 } 6771 6772 if (LHSType->isObjCObjectPointerType() || 6773 RHSType->isObjCObjectPointerType()) { 6774 const PointerType *LPT = LHSType->getAs<PointerType>(); 6775 const PointerType *RPT = RHSType->getAs<PointerType>(); 6776 if (LPT || RPT) { 6777 bool LPtrToVoid = LPT ? LPT->getPointeeType()->isVoidType() : false; 6778 bool RPtrToVoid = RPT ? RPT->getPointeeType()->isVoidType() : false; 6779 6780 if (!LPtrToVoid && !RPtrToVoid && 6781 !Context.typesAreCompatible(LHSType, RHSType)) { 6782 diagnoseDistinctPointerComparison(*this, Loc, LHS, RHS, 6783 /*isError*/false); 6784 } 6785 if (LHSIsNull && !RHSIsNull) 6786 LHS = ImpCastExprToType(LHS.take(), RHSType, 6787 RPT ? CK_BitCast :CK_CPointerToObjCPointerCast); 6788 else 6789 RHS = ImpCastExprToType(RHS.take(), LHSType, 6790 LPT ? CK_BitCast :CK_CPointerToObjCPointerCast); 6791 return ResultTy; 6792 } 6793 if (LHSType->isObjCObjectPointerType() && 6794 RHSType->isObjCObjectPointerType()) { 6795 if (!Context.areComparableObjCPointerTypes(LHSType, RHSType)) 6796 diagnoseDistinctPointerComparison(*this, Loc, LHS, RHS, 6797 /*isError*/false); 6798 if (LHSIsNull && !RHSIsNull) 6799 LHS = ImpCastExprToType(LHS.take(), RHSType, CK_BitCast); 6800 else 6801 RHS = ImpCastExprToType(RHS.take(), LHSType, CK_BitCast); 6802 return ResultTy; 6803 } 6804 } 6805 if ((LHSType->isAnyPointerType() && RHSType->isIntegerType()) || 6806 (LHSType->isIntegerType() && RHSType->isAnyPointerType())) { 6807 unsigned DiagID = 0; 6808 bool isError = false; 6809 if ((LHSIsNull && LHSType->isIntegerType()) || 6810 (RHSIsNull && RHSType->isIntegerType())) { 6811 if (IsRelational && !getLangOptions().CPlusPlus) 6812 DiagID = diag::ext_typecheck_ordered_comparison_of_pointer_and_zero; 6813 } else if (IsRelational && !getLangOptions().CPlusPlus) 6814 DiagID = diag::ext_typecheck_ordered_comparison_of_pointer_integer; 6815 else if (getLangOptions().CPlusPlus) { 6816 DiagID = diag::err_typecheck_comparison_of_pointer_integer; 6817 isError = true; 6818 } else 6819 DiagID = diag::ext_typecheck_comparison_of_pointer_integer; 6820 6821 if (DiagID) { 6822 Diag(Loc, DiagID) 6823 << LHSType << RHSType << LHS.get()->getSourceRange() 6824 << RHS.get()->getSourceRange(); 6825 if (isError) 6826 return QualType(); 6827 } 6828 6829 if (LHSType->isIntegerType()) 6830 LHS = ImpCastExprToType(LHS.take(), RHSType, 6831 LHSIsNull ? CK_NullToPointer : CK_IntegralToPointer); 6832 else 6833 RHS = ImpCastExprToType(RHS.take(), LHSType, 6834 RHSIsNull ? CK_NullToPointer : CK_IntegralToPointer); 6835 return ResultTy; 6836 } 6837 6838 // Handle block pointers. 6839 if (!IsRelational && RHSIsNull 6840 && LHSType->isBlockPointerType() && RHSType->isIntegerType()) { 6841 RHS = ImpCastExprToType(RHS.take(), LHSType, CK_NullToPointer); 6842 return ResultTy; 6843 } 6844 if (!IsRelational && LHSIsNull 6845 && LHSType->isIntegerType() && RHSType->isBlockPointerType()) { 6846 LHS = ImpCastExprToType(LHS.take(), RHSType, CK_NullToPointer); 6847 return ResultTy; 6848 } 6849 6850 return InvalidOperands(Loc, LHS, RHS); 6851} 6852 6853/// CheckVectorCompareOperands - vector comparisons are a clang extension that 6854/// operates on extended vector types. Instead of producing an IntTy result, 6855/// like a scalar comparison, a vector comparison produces a vector of integer 6856/// types. 6857QualType Sema::CheckVectorCompareOperands(ExprResult &LHS, ExprResult &RHS, 6858 SourceLocation Loc, 6859 bool IsRelational) { 6860 // Check to make sure we're operating on vectors of the same type and width, 6861 // Allowing one side to be a scalar of element type. 6862 QualType vType = CheckVectorOperands(LHS, RHS, Loc, /*isCompAssign*/false); 6863 if (vType.isNull()) 6864 return vType; 6865 6866 QualType LHSType = LHS.get()->getType(); 6867 QualType RHSType = RHS.get()->getType(); 6868 6869 // If AltiVec, the comparison results in a numeric type, i.e. 6870 // bool for C++, int for C 6871 if (vType->getAs<VectorType>()->getVectorKind() == VectorType::AltiVecVector) 6872 return Context.getLogicalOperationType(); 6873 6874 // For non-floating point types, check for self-comparisons of the form 6875 // x == x, x != x, x < x, etc. These always evaluate to a constant, and 6876 // often indicate logic errors in the program. 6877 if (!LHSType->hasFloatingRepresentation()) { 6878 if (DeclRefExpr* DRL 6879 = dyn_cast<DeclRefExpr>(LHS.get()->IgnoreParenImpCasts())) 6880 if (DeclRefExpr* DRR 6881 = dyn_cast<DeclRefExpr>(RHS.get()->IgnoreParenImpCasts())) 6882 if (DRL->getDecl() == DRR->getDecl()) 6883 DiagRuntimeBehavior(Loc, 0, 6884 PDiag(diag::warn_comparison_always) 6885 << 0 // self- 6886 << 2 // "a constant" 6887 ); 6888 } 6889 6890 // Check for comparisons of floating point operands using != and ==. 6891 if (!IsRelational && LHSType->hasFloatingRepresentation()) { 6892 assert (RHSType->hasFloatingRepresentation()); 6893 CheckFloatComparison(Loc, LHS.get(), RHS.get()); 6894 } 6895 6896 // Return a signed type that is of identical size and number of elements. 6897 // For floating point vectors, return an integer type of identical size 6898 // and number of elements. 6899 const VectorType *VTy = LHSType->getAs<VectorType>(); 6900 unsigned TypeSize = Context.getTypeSize(VTy->getElementType()); 6901 if (TypeSize == Context.getTypeSize(Context.CharTy)) 6902 return Context.getExtVectorType(Context.CharTy, VTy->getNumElements()); 6903 else if (TypeSize == Context.getTypeSize(Context.ShortTy)) 6904 return Context.getExtVectorType(Context.ShortTy, VTy->getNumElements()); 6905 else if (TypeSize == Context.getTypeSize(Context.IntTy)) 6906 return Context.getExtVectorType(Context.IntTy, VTy->getNumElements()); 6907 else if (TypeSize == Context.getTypeSize(Context.LongTy)) 6908 return Context.getExtVectorType(Context.LongTy, VTy->getNumElements()); 6909 assert(TypeSize == Context.getTypeSize(Context.LongLongTy) && 6910 "Unhandled vector element size in vector compare"); 6911 return Context.getExtVectorType(Context.LongLongTy, VTy->getNumElements()); 6912} 6913 6914inline QualType Sema::CheckBitwiseOperands( 6915 ExprResult &LHS, ExprResult &RHS, SourceLocation Loc, bool IsCompAssign) { 6916 checkArithmeticNull(*this, LHS, RHS, Loc, /*isCompare=*/false); 6917 6918 if (LHS.get()->getType()->isVectorType() || 6919 RHS.get()->getType()->isVectorType()) { 6920 if (LHS.get()->getType()->hasIntegerRepresentation() && 6921 RHS.get()->getType()->hasIntegerRepresentation()) 6922 return CheckVectorOperands(LHS, RHS, Loc, IsCompAssign); 6923 6924 return InvalidOperands(Loc, LHS, RHS); 6925 } 6926 6927 ExprResult LHSResult = Owned(LHS), RHSResult = Owned(RHS); 6928 QualType compType = UsualArithmeticConversions(LHSResult, RHSResult, 6929 IsCompAssign); 6930 if (LHSResult.isInvalid() || RHSResult.isInvalid()) 6931 return QualType(); 6932 LHS = LHSResult.take(); 6933 RHS = RHSResult.take(); 6934 6935 if (LHS.get()->getType()->isIntegralOrUnscopedEnumerationType() && 6936 RHS.get()->getType()->isIntegralOrUnscopedEnumerationType()) 6937 return compType; 6938 return InvalidOperands(Loc, LHS, RHS); 6939} 6940 6941inline QualType Sema::CheckLogicalOperands( // C99 6.5.[13,14] 6942 ExprResult &LHS, ExprResult &RHS, SourceLocation Loc, unsigned Opc) { 6943 6944 // Diagnose cases where the user write a logical and/or but probably meant a 6945 // bitwise one. We do this when the LHS is a non-bool integer and the RHS 6946 // is a constant. 6947 if (LHS.get()->getType()->isIntegerType() && 6948 !LHS.get()->getType()->isBooleanType() && 6949 RHS.get()->getType()->isIntegerType() && !RHS.get()->isValueDependent() && 6950 // Don't warn in macros or template instantiations. 6951 !Loc.isMacroID() && ActiveTemplateInstantiations.empty()) { 6952 // If the RHS can be constant folded, and if it constant folds to something 6953 // that isn't 0 or 1 (which indicate a potential logical operation that 6954 // happened to fold to true/false) then warn. 6955 // Parens on the RHS are ignored. 6956 llvm::APSInt Result; 6957 if (RHS.get()->EvaluateAsInt(Result, Context)) 6958 if ((getLangOptions().Bool && !RHS.get()->getType()->isBooleanType()) || 6959 (Result != 0 && Result != 1)) { 6960 Diag(Loc, diag::warn_logical_instead_of_bitwise) 6961 << RHS.get()->getSourceRange() 6962 << (Opc == BO_LAnd ? "&&" : "||"); 6963 // Suggest replacing the logical operator with the bitwise version 6964 Diag(Loc, diag::note_logical_instead_of_bitwise_change_operator) 6965 << (Opc == BO_LAnd ? "&" : "|") 6966 << FixItHint::CreateReplacement(SourceRange( 6967 Loc, Lexer::getLocForEndOfToken(Loc, 0, getSourceManager(), 6968 getLangOptions())), 6969 Opc == BO_LAnd ? "&" : "|"); 6970 if (Opc == BO_LAnd) 6971 // Suggest replacing "Foo() && kNonZero" with "Foo()" 6972 Diag(Loc, diag::note_logical_instead_of_bitwise_remove_constant) 6973 << FixItHint::CreateRemoval( 6974 SourceRange( 6975 Lexer::getLocForEndOfToken(LHS.get()->getLocEnd(), 6976 0, getSourceManager(), 6977 getLangOptions()), 6978 RHS.get()->getLocEnd())); 6979 } 6980 } 6981 6982 if (!Context.getLangOptions().CPlusPlus) { 6983 LHS = UsualUnaryConversions(LHS.take()); 6984 if (LHS.isInvalid()) 6985 return QualType(); 6986 6987 RHS = UsualUnaryConversions(RHS.take()); 6988 if (RHS.isInvalid()) 6989 return QualType(); 6990 6991 if (!LHS.get()->getType()->isScalarType() || 6992 !RHS.get()->getType()->isScalarType()) 6993 return InvalidOperands(Loc, LHS, RHS); 6994 6995 return Context.IntTy; 6996 } 6997 6998 // The following is safe because we only use this method for 6999 // non-overloadable operands. 7000 7001 // C++ [expr.log.and]p1 7002 // C++ [expr.log.or]p1 7003 // The operands are both contextually converted to type bool. 7004 ExprResult LHSRes = PerformContextuallyConvertToBool(LHS.get()); 7005 if (LHSRes.isInvalid()) 7006 return InvalidOperands(Loc, LHS, RHS); 7007 LHS = move(LHSRes); 7008 7009 ExprResult RHSRes = PerformContextuallyConvertToBool(RHS.get()); 7010 if (RHSRes.isInvalid()) 7011 return InvalidOperands(Loc, LHS, RHS); 7012 RHS = move(RHSRes); 7013 7014 // C++ [expr.log.and]p2 7015 // C++ [expr.log.or]p2 7016 // The result is a bool. 7017 return Context.BoolTy; 7018} 7019 7020/// IsReadonlyProperty - Verify that otherwise a valid l-value expression 7021/// is a read-only property; return true if so. A readonly property expression 7022/// depends on various declarations and thus must be treated specially. 7023/// 7024static bool IsReadonlyProperty(Expr *E, Sema &S) { 7025 const ObjCPropertyRefExpr *PropExpr = dyn_cast<ObjCPropertyRefExpr>(E); 7026 if (!PropExpr) return false; 7027 if (PropExpr->isImplicitProperty()) return false; 7028 7029 ObjCPropertyDecl *PDecl = PropExpr->getExplicitProperty(); 7030 QualType BaseType = PropExpr->isSuperReceiver() ? 7031 PropExpr->getSuperReceiverType() : 7032 PropExpr->getBase()->getType(); 7033 7034 if (const ObjCObjectPointerType *OPT = 7035 BaseType->getAsObjCInterfacePointerType()) 7036 if (ObjCInterfaceDecl *IFace = OPT->getInterfaceDecl()) 7037 if (S.isPropertyReadonly(PDecl, IFace)) 7038 return true; 7039 return false; 7040} 7041 7042static bool IsConstProperty(Expr *E, Sema &S) { 7043 const ObjCPropertyRefExpr *PropExpr = dyn_cast<ObjCPropertyRefExpr>(E); 7044 if (!PropExpr) return false; 7045 if (PropExpr->isImplicitProperty()) return false; 7046 7047 ObjCPropertyDecl *PDecl = PropExpr->getExplicitProperty(); 7048 QualType T = PDecl->getType().getNonReferenceType(); 7049 return T.isConstQualified(); 7050} 7051 7052static bool IsReadonlyMessage(Expr *E, Sema &S) { 7053 const MemberExpr *ME = dyn_cast<MemberExpr>(E); 7054 if (!ME) return false; 7055 if (!isa<FieldDecl>(ME->getMemberDecl())) return false; 7056 ObjCMessageExpr *Base = 7057 dyn_cast<ObjCMessageExpr>(ME->getBase()->IgnoreParenImpCasts()); 7058 if (!Base) return false; 7059 return Base->getMethodDecl() != 0; 7060} 7061 7062/// CheckForModifiableLvalue - Verify that E is a modifiable lvalue. If not, 7063/// emit an error and return true. If so, return false. 7064static bool CheckForModifiableLvalue(Expr *E, SourceLocation Loc, Sema &S) { 7065 SourceLocation OrigLoc = Loc; 7066 Expr::isModifiableLvalueResult IsLV = E->isModifiableLvalue(S.Context, 7067 &Loc); 7068 if (IsLV == Expr::MLV_Valid && IsReadonlyProperty(E, S)) 7069 IsLV = Expr::MLV_ReadonlyProperty; 7070 else if (Expr::MLV_ConstQualified && IsConstProperty(E, S)) 7071 IsLV = Expr::MLV_Valid; 7072 else if (IsLV == Expr::MLV_ClassTemporary && IsReadonlyMessage(E, S)) 7073 IsLV = Expr::MLV_InvalidMessageExpression; 7074 if (IsLV == Expr::MLV_Valid) 7075 return false; 7076 7077 unsigned Diag = 0; 7078 bool NeedType = false; 7079 switch (IsLV) { // C99 6.5.16p2 7080 case Expr::MLV_ConstQualified: 7081 Diag = diag::err_typecheck_assign_const; 7082 7083 // In ARC, use some specialized diagnostics for occasions where we 7084 // infer 'const'. These are always pseudo-strong variables. 7085 if (S.getLangOptions().ObjCAutoRefCount) { 7086 DeclRefExpr *declRef = dyn_cast<DeclRefExpr>(E->IgnoreParenCasts()); 7087 if (declRef && isa<VarDecl>(declRef->getDecl())) { 7088 VarDecl *var = cast<VarDecl>(declRef->getDecl()); 7089 7090 // Use the normal diagnostic if it's pseudo-__strong but the 7091 // user actually wrote 'const'. 7092 if (var->isARCPseudoStrong() && 7093 (!var->getTypeSourceInfo() || 7094 !var->getTypeSourceInfo()->getType().isConstQualified())) { 7095 // There are two pseudo-strong cases: 7096 // - self 7097 ObjCMethodDecl *method = S.getCurMethodDecl(); 7098 if (method && var == method->getSelfDecl()) 7099 Diag = method->isClassMethod() 7100 ? diag::err_typecheck_arc_assign_self_class_method 7101 : diag::err_typecheck_arc_assign_self; 7102 7103 // - fast enumeration variables 7104 else 7105 Diag = diag::err_typecheck_arr_assign_enumeration; 7106 7107 SourceRange Assign; 7108 if (Loc != OrigLoc) 7109 Assign = SourceRange(OrigLoc, OrigLoc); 7110 S.Diag(Loc, Diag) << E->getSourceRange() << Assign; 7111 // We need to preserve the AST regardless, so migration tool 7112 // can do its job. 7113 return false; 7114 } 7115 } 7116 } 7117 7118 break; 7119 case Expr::MLV_ArrayType: 7120 Diag = diag::err_typecheck_array_not_modifiable_lvalue; 7121 NeedType = true; 7122 break; 7123 case Expr::MLV_NotObjectType: 7124 Diag = diag::err_typecheck_non_object_not_modifiable_lvalue; 7125 NeedType = true; 7126 break; 7127 case Expr::MLV_LValueCast: 7128 Diag = diag::err_typecheck_lvalue_casts_not_supported; 7129 break; 7130 case Expr::MLV_Valid: 7131 llvm_unreachable("did not take early return for MLV_Valid"); 7132 case Expr::MLV_InvalidExpression: 7133 case Expr::MLV_MemberFunction: 7134 case Expr::MLV_ClassTemporary: 7135 Diag = diag::err_typecheck_expression_not_modifiable_lvalue; 7136 break; 7137 case Expr::MLV_IncompleteType: 7138 case Expr::MLV_IncompleteVoidType: 7139 return S.RequireCompleteType(Loc, E->getType(), 7140 S.PDiag(diag::err_typecheck_incomplete_type_not_modifiable_lvalue) 7141 << E->getSourceRange()); 7142 case Expr::MLV_DuplicateVectorComponents: 7143 Diag = diag::err_typecheck_duplicate_vector_components_not_mlvalue; 7144 break; 7145 case Expr::MLV_NotBlockQualified: 7146 Diag = diag::err_block_decl_ref_not_modifiable_lvalue; 7147 break; 7148 case Expr::MLV_ReadonlyProperty: 7149 case Expr::MLV_NoSetterProperty: 7150 llvm_unreachable("readonly properties should be processed differently"); 7151 break; 7152 case Expr::MLV_InvalidMessageExpression: 7153 Diag = diag::error_readonly_message_assignment; 7154 break; 7155 case Expr::MLV_SubObjCPropertySetting: 7156 Diag = diag::error_no_subobject_property_setting; 7157 break; 7158 } 7159 7160 SourceRange Assign; 7161 if (Loc != OrigLoc) 7162 Assign = SourceRange(OrigLoc, OrigLoc); 7163 if (NeedType) 7164 S.Diag(Loc, Diag) << E->getType() << E->getSourceRange() << Assign; 7165 else 7166 S.Diag(Loc, Diag) << E->getSourceRange() << Assign; 7167 return true; 7168} 7169 7170 7171 7172// C99 6.5.16.1 7173QualType Sema::CheckAssignmentOperands(Expr *LHSExpr, ExprResult &RHS, 7174 SourceLocation Loc, 7175 QualType CompoundType) { 7176 assert(!LHSExpr->hasPlaceholderType(BuiltinType::PseudoObject)); 7177 7178 // Verify that LHS is a modifiable lvalue, and emit error if not. 7179 if (CheckForModifiableLvalue(LHSExpr, Loc, *this)) 7180 return QualType(); 7181 7182 QualType LHSType = LHSExpr->getType(); 7183 QualType RHSType = CompoundType.isNull() ? RHS.get()->getType() : 7184 CompoundType; 7185 AssignConvertType ConvTy; 7186 if (CompoundType.isNull()) { 7187 QualType LHSTy(LHSType); 7188 ConvTy = CheckSingleAssignmentConstraints(LHSTy, RHS); 7189 if (RHS.isInvalid()) 7190 return QualType(); 7191 // Special case of NSObject attributes on c-style pointer types. 7192 if (ConvTy == IncompatiblePointer && 7193 ((Context.isObjCNSObjectType(LHSType) && 7194 RHSType->isObjCObjectPointerType()) || 7195 (Context.isObjCNSObjectType(RHSType) && 7196 LHSType->isObjCObjectPointerType()))) 7197 ConvTy = Compatible; 7198 7199 if (ConvTy == Compatible && 7200 getLangOptions().ObjCNonFragileABI && 7201 LHSType->isObjCObjectType()) 7202 Diag(Loc, diag::err_assignment_requires_nonfragile_object) 7203 << LHSType; 7204 7205 // If the RHS is a unary plus or minus, check to see if they = and + are 7206 // right next to each other. If so, the user may have typo'd "x =+ 4" 7207 // instead of "x += 4". 7208 Expr *RHSCheck = RHS.get(); 7209 if (ImplicitCastExpr *ICE = dyn_cast<ImplicitCastExpr>(RHSCheck)) 7210 RHSCheck = ICE->getSubExpr(); 7211 if (UnaryOperator *UO = dyn_cast<UnaryOperator>(RHSCheck)) { 7212 if ((UO->getOpcode() == UO_Plus || 7213 UO->getOpcode() == UO_Minus) && 7214 Loc.isFileID() && UO->getOperatorLoc().isFileID() && 7215 // Only if the two operators are exactly adjacent. 7216 Loc.getLocWithOffset(1) == UO->getOperatorLoc() && 7217 // And there is a space or other character before the subexpr of the 7218 // unary +/-. We don't want to warn on "x=-1". 7219 Loc.getLocWithOffset(2) != UO->getSubExpr()->getLocStart() && 7220 UO->getSubExpr()->getLocStart().isFileID()) { 7221 Diag(Loc, diag::warn_not_compound_assign) 7222 << (UO->getOpcode() == UO_Plus ? "+" : "-") 7223 << SourceRange(UO->getOperatorLoc(), UO->getOperatorLoc()); 7224 } 7225 } 7226 7227 if (ConvTy == Compatible) { 7228 if (LHSType.getObjCLifetime() == Qualifiers::OCL_Strong) 7229 checkRetainCycles(LHSExpr, RHS.get()); 7230 else if (getLangOptions().ObjCAutoRefCount) 7231 checkUnsafeExprAssigns(Loc, LHSExpr, RHS.get()); 7232 } 7233 } else { 7234 // Compound assignment "x += y" 7235 ConvTy = CheckAssignmentConstraints(Loc, LHSType, RHSType); 7236 } 7237 7238 if (DiagnoseAssignmentResult(ConvTy, Loc, LHSType, RHSType, 7239 RHS.get(), AA_Assigning)) 7240 return QualType(); 7241 7242 CheckForNullPointerDereference(*this, LHSExpr); 7243 7244 // C99 6.5.16p3: The type of an assignment expression is the type of the 7245 // left operand unless the left operand has qualified type, in which case 7246 // it is the unqualified version of the type of the left operand. 7247 // C99 6.5.16.1p2: In simple assignment, the value of the right operand 7248 // is converted to the type of the assignment expression (above). 7249 // C++ 5.17p1: the type of the assignment expression is that of its left 7250 // operand. 7251 return (getLangOptions().CPlusPlus 7252 ? LHSType : LHSType.getUnqualifiedType()); 7253} 7254 7255// C99 6.5.17 7256static QualType CheckCommaOperands(Sema &S, ExprResult &LHS, ExprResult &RHS, 7257 SourceLocation Loc) { 7258 S.DiagnoseUnusedExprResult(LHS.get()); 7259 7260 LHS = S.CheckPlaceholderExpr(LHS.take()); 7261 RHS = S.CheckPlaceholderExpr(RHS.take()); 7262 if (LHS.isInvalid() || RHS.isInvalid()) 7263 return QualType(); 7264 7265 // C's comma performs lvalue conversion (C99 6.3.2.1) on both its 7266 // operands, but not unary promotions. 7267 // C++'s comma does not do any conversions at all (C++ [expr.comma]p1). 7268 7269 // So we treat the LHS as a ignored value, and in C++ we allow the 7270 // containing site to determine what should be done with the RHS. 7271 LHS = S.IgnoredValueConversions(LHS.take()); 7272 if (LHS.isInvalid()) 7273 return QualType(); 7274 7275 if (!S.getLangOptions().CPlusPlus) { 7276 RHS = S.DefaultFunctionArrayLvalueConversion(RHS.take()); 7277 if (RHS.isInvalid()) 7278 return QualType(); 7279 if (!RHS.get()->getType()->isVoidType()) 7280 S.RequireCompleteType(Loc, RHS.get()->getType(), 7281 diag::err_incomplete_type); 7282 } 7283 7284 return RHS.get()->getType(); 7285} 7286 7287/// CheckIncrementDecrementOperand - unlike most "Check" methods, this routine 7288/// doesn't need to call UsualUnaryConversions or UsualArithmeticConversions. 7289static QualType CheckIncrementDecrementOperand(Sema &S, Expr *Op, 7290 ExprValueKind &VK, 7291 SourceLocation OpLoc, 7292 bool IsInc, bool IsPrefix) { 7293 if (Op->isTypeDependent()) 7294 return S.Context.DependentTy; 7295 7296 QualType ResType = Op->getType(); 7297 assert(!ResType.isNull() && "no type for increment/decrement expression"); 7298 7299 if (S.getLangOptions().CPlusPlus && ResType->isBooleanType()) { 7300 // Decrement of bool is not allowed. 7301 if (!IsInc) { 7302 S.Diag(OpLoc, diag::err_decrement_bool) << Op->getSourceRange(); 7303 return QualType(); 7304 } 7305 // Increment of bool sets it to true, but is deprecated. 7306 S.Diag(OpLoc, diag::warn_increment_bool) << Op->getSourceRange(); 7307 } else if (ResType->isRealType()) { 7308 // OK! 7309 } else if (ResType->isAnyPointerType()) { 7310 // C99 6.5.2.4p2, 6.5.6p2 7311 if (!checkArithmeticOpPointerOperand(S, OpLoc, Op)) 7312 return QualType(); 7313 7314 // Diagnose bad cases where we step over interface counts. 7315 else if (!checkArithmethicPointerOnNonFragileABI(S, OpLoc, Op)) 7316 return QualType(); 7317 } else if (ResType->isAnyComplexType()) { 7318 // C99 does not support ++/-- on complex types, we allow as an extension. 7319 S.Diag(OpLoc, diag::ext_integer_increment_complex) 7320 << ResType << Op->getSourceRange(); 7321 } else if (ResType->isPlaceholderType()) { 7322 ExprResult PR = S.CheckPlaceholderExpr(Op); 7323 if (PR.isInvalid()) return QualType(); 7324 return CheckIncrementDecrementOperand(S, PR.take(), VK, OpLoc, 7325 IsInc, IsPrefix); 7326 } else if (S.getLangOptions().AltiVec && ResType->isVectorType()) { 7327 // OK! ( C/C++ Language Extensions for CBEA(Version 2.6) 10.3 ) 7328 } else { 7329 S.Diag(OpLoc, diag::err_typecheck_illegal_increment_decrement) 7330 << ResType << int(IsInc) << Op->getSourceRange(); 7331 return QualType(); 7332 } 7333 // At this point, we know we have a real, complex or pointer type. 7334 // Now make sure the operand is a modifiable lvalue. 7335 if (CheckForModifiableLvalue(Op, OpLoc, S)) 7336 return QualType(); 7337 // In C++, a prefix increment is the same type as the operand. Otherwise 7338 // (in C or with postfix), the increment is the unqualified type of the 7339 // operand. 7340 if (IsPrefix && S.getLangOptions().CPlusPlus) { 7341 VK = VK_LValue; 7342 return ResType; 7343 } else { 7344 VK = VK_RValue; 7345 return ResType.getUnqualifiedType(); 7346 } 7347} 7348 7349 7350/// getPrimaryDecl - Helper function for CheckAddressOfOperand(). 7351/// This routine allows us to typecheck complex/recursive expressions 7352/// where the declaration is needed for type checking. We only need to 7353/// handle cases when the expression references a function designator 7354/// or is an lvalue. Here are some examples: 7355/// - &(x) => x 7356/// - &*****f => f for f a function designator. 7357/// - &s.xx => s 7358/// - &s.zz[1].yy -> s, if zz is an array 7359/// - *(x + 1) -> x, if x is an array 7360/// - &"123"[2] -> 0 7361/// - & __real__ x -> x 7362static ValueDecl *getPrimaryDecl(Expr *E) { 7363 switch (E->getStmtClass()) { 7364 case Stmt::DeclRefExprClass: 7365 return cast<DeclRefExpr>(E)->getDecl(); 7366 case Stmt::MemberExprClass: 7367 // If this is an arrow operator, the address is an offset from 7368 // the base's value, so the object the base refers to is 7369 // irrelevant. 7370 if (cast<MemberExpr>(E)->isArrow()) 7371 return 0; 7372 // Otherwise, the expression refers to a part of the base 7373 return getPrimaryDecl(cast<MemberExpr>(E)->getBase()); 7374 case Stmt::ArraySubscriptExprClass: { 7375 // FIXME: This code shouldn't be necessary! We should catch the implicit 7376 // promotion of register arrays earlier. 7377 Expr* Base = cast<ArraySubscriptExpr>(E)->getBase(); 7378 if (ImplicitCastExpr* ICE = dyn_cast<ImplicitCastExpr>(Base)) { 7379 if (ICE->getSubExpr()->getType()->isArrayType()) 7380 return getPrimaryDecl(ICE->getSubExpr()); 7381 } 7382 return 0; 7383 } 7384 case Stmt::UnaryOperatorClass: { 7385 UnaryOperator *UO = cast<UnaryOperator>(E); 7386 7387 switch(UO->getOpcode()) { 7388 case UO_Real: 7389 case UO_Imag: 7390 case UO_Extension: 7391 return getPrimaryDecl(UO->getSubExpr()); 7392 default: 7393 return 0; 7394 } 7395 } 7396 case Stmt::ParenExprClass: 7397 return getPrimaryDecl(cast<ParenExpr>(E)->getSubExpr()); 7398 case Stmt::ImplicitCastExprClass: 7399 // If the result of an implicit cast is an l-value, we care about 7400 // the sub-expression; otherwise, the result here doesn't matter. 7401 return getPrimaryDecl(cast<ImplicitCastExpr>(E)->getSubExpr()); 7402 default: 7403 return 0; 7404 } 7405} 7406 7407namespace { 7408 enum { 7409 AO_Bit_Field = 0, 7410 AO_Vector_Element = 1, 7411 AO_Property_Expansion = 2, 7412 AO_Register_Variable = 3, 7413 AO_No_Error = 4 7414 }; 7415} 7416/// \brief Diagnose invalid operand for address of operations. 7417/// 7418/// \param Type The type of operand which cannot have its address taken. 7419static void diagnoseAddressOfInvalidType(Sema &S, SourceLocation Loc, 7420 Expr *E, unsigned Type) { 7421 S.Diag(Loc, diag::err_typecheck_address_of) << Type << E->getSourceRange(); 7422} 7423 7424/// CheckAddressOfOperand - The operand of & must be either a function 7425/// designator or an lvalue designating an object. If it is an lvalue, the 7426/// object cannot be declared with storage class register or be a bit field. 7427/// Note: The usual conversions are *not* applied to the operand of the & 7428/// operator (C99 6.3.2.1p[2-4]), and its result is never an lvalue. 7429/// In C++, the operand might be an overloaded function name, in which case 7430/// we allow the '&' but retain the overloaded-function type. 7431static QualType CheckAddressOfOperand(Sema &S, ExprResult &OrigOp, 7432 SourceLocation OpLoc) { 7433 if (const BuiltinType *PTy = OrigOp.get()->getType()->getAsPlaceholderType()){ 7434 if (PTy->getKind() == BuiltinType::Overload) { 7435 if (!isa<OverloadExpr>(OrigOp.get()->IgnoreParens())) { 7436 S.Diag(OpLoc, diag::err_typecheck_invalid_lvalue_addrof) 7437 << OrigOp.get()->getSourceRange(); 7438 return QualType(); 7439 } 7440 7441 return S.Context.OverloadTy; 7442 } 7443 7444 if (PTy->getKind() == BuiltinType::UnknownAny) 7445 return S.Context.UnknownAnyTy; 7446 7447 if (PTy->getKind() == BuiltinType::BoundMember) { 7448 S.Diag(OpLoc, diag::err_invalid_form_pointer_member_function) 7449 << OrigOp.get()->getSourceRange(); 7450 return QualType(); 7451 } 7452 7453 OrigOp = S.CheckPlaceholderExpr(OrigOp.take()); 7454 if (OrigOp.isInvalid()) return QualType(); 7455 } 7456 7457 if (OrigOp.get()->isTypeDependent()) 7458 return S.Context.DependentTy; 7459 7460 assert(!OrigOp.get()->getType()->isPlaceholderType()); 7461 7462 // Make sure to ignore parentheses in subsequent checks 7463 Expr *op = OrigOp.get()->IgnoreParens(); 7464 7465 if (S.getLangOptions().C99) { 7466 // Implement C99-only parts of addressof rules. 7467 if (UnaryOperator* uOp = dyn_cast<UnaryOperator>(op)) { 7468 if (uOp->getOpcode() == UO_Deref) 7469 // Per C99 6.5.3.2, the address of a deref always returns a valid result 7470 // (assuming the deref expression is valid). 7471 return uOp->getSubExpr()->getType(); 7472 } 7473 // Technically, there should be a check for array subscript 7474 // expressions here, but the result of one is always an lvalue anyway. 7475 } 7476 ValueDecl *dcl = getPrimaryDecl(op); 7477 Expr::LValueClassification lval = op->ClassifyLValue(S.Context); 7478 unsigned AddressOfError = AO_No_Error; 7479 7480 if (lval == Expr::LV_ClassTemporary) { 7481 bool sfinae = S.isSFINAEContext(); 7482 S.Diag(OpLoc, sfinae ? diag::err_typecheck_addrof_class_temporary 7483 : diag::ext_typecheck_addrof_class_temporary) 7484 << op->getType() << op->getSourceRange(); 7485 if (sfinae) 7486 return QualType(); 7487 } else if (isa<ObjCSelectorExpr>(op)) { 7488 return S.Context.getPointerType(op->getType()); 7489 } else if (lval == Expr::LV_MemberFunction) { 7490 // If it's an instance method, make a member pointer. 7491 // The expression must have exactly the form &A::foo. 7492 7493 // If the underlying expression isn't a decl ref, give up. 7494 if (!isa<DeclRefExpr>(op)) { 7495 S.Diag(OpLoc, diag::err_invalid_form_pointer_member_function) 7496 << OrigOp.get()->getSourceRange(); 7497 return QualType(); 7498 } 7499 DeclRefExpr *DRE = cast<DeclRefExpr>(op); 7500 CXXMethodDecl *MD = cast<CXXMethodDecl>(DRE->getDecl()); 7501 7502 // The id-expression was parenthesized. 7503 if (OrigOp.get() != DRE) { 7504 S.Diag(OpLoc, diag::err_parens_pointer_member_function) 7505 << OrigOp.get()->getSourceRange(); 7506 7507 // The method was named without a qualifier. 7508 } else if (!DRE->getQualifier()) { 7509 S.Diag(OpLoc, diag::err_unqualified_pointer_member_function) 7510 << op->getSourceRange(); 7511 } 7512 7513 return S.Context.getMemberPointerType(op->getType(), 7514 S.Context.getTypeDeclType(MD->getParent()).getTypePtr()); 7515 } else if (lval != Expr::LV_Valid && lval != Expr::LV_IncompleteVoidType) { 7516 // C99 6.5.3.2p1 7517 // The operand must be either an l-value or a function designator 7518 if (!op->getType()->isFunctionType()) { 7519 // Use a special diagnostic for loads from property references. 7520 if (isa<PseudoObjectExpr>(op)) { 7521 AddressOfError = AO_Property_Expansion; 7522 } else { 7523 // FIXME: emit more specific diag... 7524 S.Diag(OpLoc, diag::err_typecheck_invalid_lvalue_addrof) 7525 << op->getSourceRange(); 7526 return QualType(); 7527 } 7528 } 7529 } else if (op->getObjectKind() == OK_BitField) { // C99 6.5.3.2p1 7530 // The operand cannot be a bit-field 7531 AddressOfError = AO_Bit_Field; 7532 } else if (op->getObjectKind() == OK_VectorComponent) { 7533 // The operand cannot be an element of a vector 7534 AddressOfError = AO_Vector_Element; 7535 } else if (dcl) { // C99 6.5.3.2p1 7536 // We have an lvalue with a decl. Make sure the decl is not declared 7537 // with the register storage-class specifier. 7538 if (const VarDecl *vd = dyn_cast<VarDecl>(dcl)) { 7539 // in C++ it is not error to take address of a register 7540 // variable (c++03 7.1.1P3) 7541 if (vd->getStorageClass() == SC_Register && 7542 !S.getLangOptions().CPlusPlus) { 7543 AddressOfError = AO_Register_Variable; 7544 } 7545 } else if (isa<FunctionTemplateDecl>(dcl)) { 7546 return S.Context.OverloadTy; 7547 } else if (isa<FieldDecl>(dcl) || isa<IndirectFieldDecl>(dcl)) { 7548 // Okay: we can take the address of a field. 7549 // Could be a pointer to member, though, if there is an explicit 7550 // scope qualifier for the class. 7551 if (isa<DeclRefExpr>(op) && cast<DeclRefExpr>(op)->getQualifier()) { 7552 DeclContext *Ctx = dcl->getDeclContext(); 7553 if (Ctx && Ctx->isRecord()) { 7554 if (dcl->getType()->isReferenceType()) { 7555 S.Diag(OpLoc, 7556 diag::err_cannot_form_pointer_to_member_of_reference_type) 7557 << dcl->getDeclName() << dcl->getType(); 7558 return QualType(); 7559 } 7560 7561 while (cast<RecordDecl>(Ctx)->isAnonymousStructOrUnion()) 7562 Ctx = Ctx->getParent(); 7563 return S.Context.getMemberPointerType(op->getType(), 7564 S.Context.getTypeDeclType(cast<RecordDecl>(Ctx)).getTypePtr()); 7565 } 7566 } 7567 } else if (!isa<FunctionDecl>(dcl) && !isa<NonTypeTemplateParmDecl>(dcl)) 7568 llvm_unreachable("Unknown/unexpected decl type"); 7569 } 7570 7571 if (AddressOfError != AO_No_Error) { 7572 diagnoseAddressOfInvalidType(S, OpLoc, op, AddressOfError); 7573 return QualType(); 7574 } 7575 7576 if (lval == Expr::LV_IncompleteVoidType) { 7577 // Taking the address of a void variable is technically illegal, but we 7578 // allow it in cases which are otherwise valid. 7579 // Example: "extern void x; void* y = &x;". 7580 S.Diag(OpLoc, diag::ext_typecheck_addrof_void) << op->getSourceRange(); 7581 } 7582 7583 // If the operand has type "type", the result has type "pointer to type". 7584 if (op->getType()->isObjCObjectType()) 7585 return S.Context.getObjCObjectPointerType(op->getType()); 7586 return S.Context.getPointerType(op->getType()); 7587} 7588 7589/// CheckIndirectionOperand - Type check unary indirection (prefix '*'). 7590static QualType CheckIndirectionOperand(Sema &S, Expr *Op, ExprValueKind &VK, 7591 SourceLocation OpLoc) { 7592 if (Op->isTypeDependent()) 7593 return S.Context.DependentTy; 7594 7595 ExprResult ConvResult = S.UsualUnaryConversions(Op); 7596 if (ConvResult.isInvalid()) 7597 return QualType(); 7598 Op = ConvResult.take(); 7599 QualType OpTy = Op->getType(); 7600 QualType Result; 7601 7602 if (isa<CXXReinterpretCastExpr>(Op)) { 7603 QualType OpOrigType = Op->IgnoreParenCasts()->getType(); 7604 S.CheckCompatibleReinterpretCast(OpOrigType, OpTy, /*IsDereference*/true, 7605 Op->getSourceRange()); 7606 } 7607 7608 // Note that per both C89 and C99, indirection is always legal, even if OpTy 7609 // is an incomplete type or void. It would be possible to warn about 7610 // dereferencing a void pointer, but it's completely well-defined, and such a 7611 // warning is unlikely to catch any mistakes. 7612 if (const PointerType *PT = OpTy->getAs<PointerType>()) 7613 Result = PT->getPointeeType(); 7614 else if (const ObjCObjectPointerType *OPT = 7615 OpTy->getAs<ObjCObjectPointerType>()) 7616 Result = OPT->getPointeeType(); 7617 else { 7618 ExprResult PR = S.CheckPlaceholderExpr(Op); 7619 if (PR.isInvalid()) return QualType(); 7620 if (PR.take() != Op) 7621 return CheckIndirectionOperand(S, PR.take(), VK, OpLoc); 7622 } 7623 7624 if (Result.isNull()) { 7625 S.Diag(OpLoc, diag::err_typecheck_indirection_requires_pointer) 7626 << OpTy << Op->getSourceRange(); 7627 return QualType(); 7628 } 7629 7630 // Dereferences are usually l-values... 7631 VK = VK_LValue; 7632 7633 // ...except that certain expressions are never l-values in C. 7634 if (!S.getLangOptions().CPlusPlus && Result.isCForbiddenLValueType()) 7635 VK = VK_RValue; 7636 7637 return Result; 7638} 7639 7640static inline BinaryOperatorKind ConvertTokenKindToBinaryOpcode( 7641 tok::TokenKind Kind) { 7642 BinaryOperatorKind Opc; 7643 switch (Kind) { 7644 default: llvm_unreachable("Unknown binop!"); 7645 case tok::periodstar: Opc = BO_PtrMemD; break; 7646 case tok::arrowstar: Opc = BO_PtrMemI; break; 7647 case tok::star: Opc = BO_Mul; break; 7648 case tok::slash: Opc = BO_Div; break; 7649 case tok::percent: Opc = BO_Rem; break; 7650 case tok::plus: Opc = BO_Add; break; 7651 case tok::minus: Opc = BO_Sub; break; 7652 case tok::lessless: Opc = BO_Shl; break; 7653 case tok::greatergreater: Opc = BO_Shr; break; 7654 case tok::lessequal: Opc = BO_LE; break; 7655 case tok::less: Opc = BO_LT; break; 7656 case tok::greaterequal: Opc = BO_GE; break; 7657 case tok::greater: Opc = BO_GT; break; 7658 case tok::exclaimequal: Opc = BO_NE; break; 7659 case tok::equalequal: Opc = BO_EQ; break; 7660 case tok::amp: Opc = BO_And; break; 7661 case tok::caret: Opc = BO_Xor; break; 7662 case tok::pipe: Opc = BO_Or; break; 7663 case tok::ampamp: Opc = BO_LAnd; break; 7664 case tok::pipepipe: Opc = BO_LOr; break; 7665 case tok::equal: Opc = BO_Assign; break; 7666 case tok::starequal: Opc = BO_MulAssign; break; 7667 case tok::slashequal: Opc = BO_DivAssign; break; 7668 case tok::percentequal: Opc = BO_RemAssign; break; 7669 case tok::plusequal: Opc = BO_AddAssign; break; 7670 case tok::minusequal: Opc = BO_SubAssign; break; 7671 case tok::lesslessequal: Opc = BO_ShlAssign; break; 7672 case tok::greatergreaterequal: Opc = BO_ShrAssign; break; 7673 case tok::ampequal: Opc = BO_AndAssign; break; 7674 case tok::caretequal: Opc = BO_XorAssign; break; 7675 case tok::pipeequal: Opc = BO_OrAssign; break; 7676 case tok::comma: Opc = BO_Comma; break; 7677 } 7678 return Opc; 7679} 7680 7681static inline UnaryOperatorKind ConvertTokenKindToUnaryOpcode( 7682 tok::TokenKind Kind) { 7683 UnaryOperatorKind Opc; 7684 switch (Kind) { 7685 default: llvm_unreachable("Unknown unary op!"); 7686 case tok::plusplus: Opc = UO_PreInc; break; 7687 case tok::minusminus: Opc = UO_PreDec; break; 7688 case tok::amp: Opc = UO_AddrOf; break; 7689 case tok::star: Opc = UO_Deref; break; 7690 case tok::plus: Opc = UO_Plus; break; 7691 case tok::minus: Opc = UO_Minus; break; 7692 case tok::tilde: Opc = UO_Not; break; 7693 case tok::exclaim: Opc = UO_LNot; break; 7694 case tok::kw___real: Opc = UO_Real; break; 7695 case tok::kw___imag: Opc = UO_Imag; break; 7696 case tok::kw___extension__: Opc = UO_Extension; break; 7697 } 7698 return Opc; 7699} 7700 7701/// DiagnoseSelfAssignment - Emits a warning if a value is assigned to itself. 7702/// This warning is only emitted for builtin assignment operations. It is also 7703/// suppressed in the event of macro expansions. 7704static void DiagnoseSelfAssignment(Sema &S, Expr *LHSExpr, Expr *RHSExpr, 7705 SourceLocation OpLoc) { 7706 if (!S.ActiveTemplateInstantiations.empty()) 7707 return; 7708 if (OpLoc.isInvalid() || OpLoc.isMacroID()) 7709 return; 7710 LHSExpr = LHSExpr->IgnoreParenImpCasts(); 7711 RHSExpr = RHSExpr->IgnoreParenImpCasts(); 7712 const DeclRefExpr *LHSDeclRef = dyn_cast<DeclRefExpr>(LHSExpr); 7713 const DeclRefExpr *RHSDeclRef = dyn_cast<DeclRefExpr>(RHSExpr); 7714 if (!LHSDeclRef || !RHSDeclRef || 7715 LHSDeclRef->getLocation().isMacroID() || 7716 RHSDeclRef->getLocation().isMacroID()) 7717 return; 7718 const ValueDecl *LHSDecl = 7719 cast<ValueDecl>(LHSDeclRef->getDecl()->getCanonicalDecl()); 7720 const ValueDecl *RHSDecl = 7721 cast<ValueDecl>(RHSDeclRef->getDecl()->getCanonicalDecl()); 7722 if (LHSDecl != RHSDecl) 7723 return; 7724 if (LHSDecl->getType().isVolatileQualified()) 7725 return; 7726 if (const ReferenceType *RefTy = LHSDecl->getType()->getAs<ReferenceType>()) 7727 if (RefTy->getPointeeType().isVolatileQualified()) 7728 return; 7729 7730 S.Diag(OpLoc, diag::warn_self_assignment) 7731 << LHSDeclRef->getType() 7732 << LHSExpr->getSourceRange() << RHSExpr->getSourceRange(); 7733} 7734 7735/// CreateBuiltinBinOp - Creates a new built-in binary operation with 7736/// operator @p Opc at location @c TokLoc. This routine only supports 7737/// built-in operations; ActOnBinOp handles overloaded operators. 7738ExprResult Sema::CreateBuiltinBinOp(SourceLocation OpLoc, 7739 BinaryOperatorKind Opc, 7740 Expr *LHSExpr, Expr *RHSExpr) { 7741 ExprResult LHS = Owned(LHSExpr), RHS = Owned(RHSExpr); 7742 QualType ResultTy; // Result type of the binary operator. 7743 // The following two variables are used for compound assignment operators 7744 QualType CompLHSTy; // Type of LHS after promotions for computation 7745 QualType CompResultTy; // Type of computation result 7746 ExprValueKind VK = VK_RValue; 7747 ExprObjectKind OK = OK_Ordinary; 7748 7749 switch (Opc) { 7750 case BO_Assign: 7751 ResultTy = CheckAssignmentOperands(LHS.get(), RHS, OpLoc, QualType()); 7752 if (getLangOptions().CPlusPlus && 7753 LHS.get()->getObjectKind() != OK_ObjCProperty) { 7754 VK = LHS.get()->getValueKind(); 7755 OK = LHS.get()->getObjectKind(); 7756 } 7757 if (!ResultTy.isNull()) 7758 DiagnoseSelfAssignment(*this, LHS.get(), RHS.get(), OpLoc); 7759 break; 7760 case BO_PtrMemD: 7761 case BO_PtrMemI: 7762 ResultTy = CheckPointerToMemberOperands(LHS, RHS, VK, OpLoc, 7763 Opc == BO_PtrMemI); 7764 break; 7765 case BO_Mul: 7766 case BO_Div: 7767 ResultTy = CheckMultiplyDivideOperands(LHS, RHS, OpLoc, false, 7768 Opc == BO_Div); 7769 break; 7770 case BO_Rem: 7771 ResultTy = CheckRemainderOperands(LHS, RHS, OpLoc); 7772 break; 7773 case BO_Add: 7774 ResultTy = CheckAdditionOperands(LHS, RHS, OpLoc); 7775 break; 7776 case BO_Sub: 7777 ResultTy = CheckSubtractionOperands(LHS, RHS, OpLoc); 7778 break; 7779 case BO_Shl: 7780 case BO_Shr: 7781 ResultTy = CheckShiftOperands(LHS, RHS, OpLoc, Opc); 7782 break; 7783 case BO_LE: 7784 case BO_LT: 7785 case BO_GE: 7786 case BO_GT: 7787 ResultTy = CheckCompareOperands(LHS, RHS, OpLoc, Opc, true); 7788 break; 7789 case BO_EQ: 7790 case BO_NE: 7791 ResultTy = CheckCompareOperands(LHS, RHS, OpLoc, Opc, false); 7792 break; 7793 case BO_And: 7794 case BO_Xor: 7795 case BO_Or: 7796 ResultTy = CheckBitwiseOperands(LHS, RHS, OpLoc); 7797 break; 7798 case BO_LAnd: 7799 case BO_LOr: 7800 ResultTy = CheckLogicalOperands(LHS, RHS, OpLoc, Opc); 7801 break; 7802 case BO_MulAssign: 7803 case BO_DivAssign: 7804 CompResultTy = CheckMultiplyDivideOperands(LHS, RHS, OpLoc, true, 7805 Opc == BO_DivAssign); 7806 CompLHSTy = CompResultTy; 7807 if (!CompResultTy.isNull() && !LHS.isInvalid() && !RHS.isInvalid()) 7808 ResultTy = CheckAssignmentOperands(LHS.get(), RHS, OpLoc, CompResultTy); 7809 break; 7810 case BO_RemAssign: 7811 CompResultTy = CheckRemainderOperands(LHS, RHS, OpLoc, true); 7812 CompLHSTy = CompResultTy; 7813 if (!CompResultTy.isNull() && !LHS.isInvalid() && !RHS.isInvalid()) 7814 ResultTy = CheckAssignmentOperands(LHS.get(), RHS, OpLoc, CompResultTy); 7815 break; 7816 case BO_AddAssign: 7817 CompResultTy = CheckAdditionOperands(LHS, RHS, OpLoc, &CompLHSTy); 7818 if (!CompResultTy.isNull() && !LHS.isInvalid() && !RHS.isInvalid()) 7819 ResultTy = CheckAssignmentOperands(LHS.get(), RHS, OpLoc, CompResultTy); 7820 break; 7821 case BO_SubAssign: 7822 CompResultTy = CheckSubtractionOperands(LHS, RHS, OpLoc, &CompLHSTy); 7823 if (!CompResultTy.isNull() && !LHS.isInvalid() && !RHS.isInvalid()) 7824 ResultTy = CheckAssignmentOperands(LHS.get(), RHS, OpLoc, CompResultTy); 7825 break; 7826 case BO_ShlAssign: 7827 case BO_ShrAssign: 7828 CompResultTy = CheckShiftOperands(LHS, RHS, OpLoc, Opc, true); 7829 CompLHSTy = CompResultTy; 7830 if (!CompResultTy.isNull() && !LHS.isInvalid() && !RHS.isInvalid()) 7831 ResultTy = CheckAssignmentOperands(LHS.get(), RHS, OpLoc, CompResultTy); 7832 break; 7833 case BO_AndAssign: 7834 case BO_XorAssign: 7835 case BO_OrAssign: 7836 CompResultTy = CheckBitwiseOperands(LHS, RHS, OpLoc, true); 7837 CompLHSTy = CompResultTy; 7838 if (!CompResultTy.isNull() && !LHS.isInvalid() && !RHS.isInvalid()) 7839 ResultTy = CheckAssignmentOperands(LHS.get(), RHS, OpLoc, CompResultTy); 7840 break; 7841 case BO_Comma: 7842 ResultTy = CheckCommaOperands(*this, LHS, RHS, OpLoc); 7843 if (getLangOptions().CPlusPlus && !RHS.isInvalid()) { 7844 VK = RHS.get()->getValueKind(); 7845 OK = RHS.get()->getObjectKind(); 7846 } 7847 break; 7848 } 7849 if (ResultTy.isNull() || LHS.isInvalid() || RHS.isInvalid()) 7850 return ExprError(); 7851 7852 // Check for array bounds violations for both sides of the BinaryOperator 7853 CheckArrayAccess(LHS.get()); 7854 CheckArrayAccess(RHS.get()); 7855 7856 if (CompResultTy.isNull()) 7857 return Owned(new (Context) BinaryOperator(LHS.take(), RHS.take(), Opc, 7858 ResultTy, VK, OK, OpLoc)); 7859 if (getLangOptions().CPlusPlus && LHS.get()->getObjectKind() != 7860 OK_ObjCProperty) { 7861 VK = VK_LValue; 7862 OK = LHS.get()->getObjectKind(); 7863 } 7864 return Owned(new (Context) CompoundAssignOperator(LHS.take(), RHS.take(), Opc, 7865 ResultTy, VK, OK, CompLHSTy, 7866 CompResultTy, OpLoc)); 7867} 7868 7869/// DiagnoseBitwisePrecedence - Emit a warning when bitwise and comparison 7870/// operators are mixed in a way that suggests that the programmer forgot that 7871/// comparison operators have higher precedence. The most typical example of 7872/// such code is "flags & 0x0020 != 0", which is equivalent to "flags & 1". 7873static void DiagnoseBitwisePrecedence(Sema &Self, BinaryOperatorKind Opc, 7874 SourceLocation OpLoc, Expr *LHSExpr, 7875 Expr *RHSExpr) { 7876 typedef BinaryOperator BinOp; 7877 BinOp::Opcode LHSopc = static_cast<BinOp::Opcode>(-1), 7878 RHSopc = static_cast<BinOp::Opcode>(-1); 7879 if (BinOp *BO = dyn_cast<BinOp>(LHSExpr)) 7880 LHSopc = BO->getOpcode(); 7881 if (BinOp *BO = dyn_cast<BinOp>(RHSExpr)) 7882 RHSopc = BO->getOpcode(); 7883 7884 // Subs are not binary operators. 7885 if (LHSopc == -1 && RHSopc == -1) 7886 return; 7887 7888 // Bitwise operations are sometimes used as eager logical ops. 7889 // Don't diagnose this. 7890 if ((BinOp::isComparisonOp(LHSopc) || BinOp::isBitwiseOp(LHSopc)) && 7891 (BinOp::isComparisonOp(RHSopc) || BinOp::isBitwiseOp(RHSopc))) 7892 return; 7893 7894 bool isLeftComp = BinOp::isComparisonOp(LHSopc); 7895 bool isRightComp = BinOp::isComparisonOp(RHSopc); 7896 if (!isLeftComp && !isRightComp) return; 7897 7898 SourceRange DiagRange = isLeftComp ? SourceRange(LHSExpr->getLocStart(), 7899 OpLoc) 7900 : SourceRange(OpLoc, RHSExpr->getLocEnd()); 7901 std::string OpStr = isLeftComp ? BinOp::getOpcodeStr(LHSopc) 7902 : BinOp::getOpcodeStr(RHSopc); 7903 SourceRange ParensRange = isLeftComp ? 7904 SourceRange(cast<BinOp>(LHSExpr)->getRHS()->getLocStart(), 7905 RHSExpr->getLocEnd()) 7906 : SourceRange(LHSExpr->getLocStart(), 7907 cast<BinOp>(RHSExpr)->getLHS()->getLocStart()); 7908 7909 Self.Diag(OpLoc, diag::warn_precedence_bitwise_rel) 7910 << DiagRange << BinOp::getOpcodeStr(Opc) << OpStr; 7911 SuggestParentheses(Self, OpLoc, 7912 Self.PDiag(diag::note_precedence_bitwise_silence) << OpStr, 7913 RHSExpr->getSourceRange()); 7914 SuggestParentheses(Self, OpLoc, 7915 Self.PDiag(diag::note_precedence_bitwise_first) << BinOp::getOpcodeStr(Opc), 7916 ParensRange); 7917} 7918 7919/// \brief It accepts a '&' expr that is inside a '|' one. 7920/// Emit a diagnostic together with a fixit hint that wraps the '&' expression 7921/// in parentheses. 7922static void 7923EmitDiagnosticForBitwiseAndInBitwiseOr(Sema &Self, SourceLocation OpLoc, 7924 BinaryOperator *Bop) { 7925 assert(Bop->getOpcode() == BO_And); 7926 Self.Diag(Bop->getOperatorLoc(), diag::warn_bitwise_and_in_bitwise_or) 7927 << Bop->getSourceRange() << OpLoc; 7928 SuggestParentheses(Self, Bop->getOperatorLoc(), 7929 Self.PDiag(diag::note_bitwise_and_in_bitwise_or_silence), 7930 Bop->getSourceRange()); 7931} 7932 7933/// \brief It accepts a '&&' expr that is inside a '||' one. 7934/// Emit a diagnostic together with a fixit hint that wraps the '&&' expression 7935/// in parentheses. 7936static void 7937EmitDiagnosticForLogicalAndInLogicalOr(Sema &Self, SourceLocation OpLoc, 7938 BinaryOperator *Bop) { 7939 assert(Bop->getOpcode() == BO_LAnd); 7940 Self.Diag(Bop->getOperatorLoc(), diag::warn_logical_and_in_logical_or) 7941 << Bop->getSourceRange() << OpLoc; 7942 SuggestParentheses(Self, Bop->getOperatorLoc(), 7943 Self.PDiag(diag::note_logical_and_in_logical_or_silence), 7944 Bop->getSourceRange()); 7945} 7946 7947/// \brief Returns true if the given expression can be evaluated as a constant 7948/// 'true'. 7949static bool EvaluatesAsTrue(Sema &S, Expr *E) { 7950 bool Res; 7951 return E->EvaluateAsBooleanCondition(Res, S.getASTContext()) && Res; 7952} 7953 7954/// \brief Returns true if the given expression can be evaluated as a constant 7955/// 'false'. 7956static bool EvaluatesAsFalse(Sema &S, Expr *E) { 7957 bool Res; 7958 return E->EvaluateAsBooleanCondition(Res, S.getASTContext()) && !Res; 7959} 7960 7961/// \brief Look for '&&' in the left hand of a '||' expr. 7962static void DiagnoseLogicalAndInLogicalOrLHS(Sema &S, SourceLocation OpLoc, 7963 Expr *LHSExpr, Expr *RHSExpr) { 7964 if (BinaryOperator *Bop = dyn_cast<BinaryOperator>(LHSExpr)) { 7965 if (Bop->getOpcode() == BO_LAnd) { 7966 // If it's "a && b || 0" don't warn since the precedence doesn't matter. 7967 if (EvaluatesAsFalse(S, RHSExpr)) 7968 return; 7969 // If it's "1 && a || b" don't warn since the precedence doesn't matter. 7970 if (!EvaluatesAsTrue(S, Bop->getLHS())) 7971 return EmitDiagnosticForLogicalAndInLogicalOr(S, OpLoc, Bop); 7972 } else if (Bop->getOpcode() == BO_LOr) { 7973 if (BinaryOperator *RBop = dyn_cast<BinaryOperator>(Bop->getRHS())) { 7974 // If it's "a || b && 1 || c" we didn't warn earlier for 7975 // "a || b && 1", but warn now. 7976 if (RBop->getOpcode() == BO_LAnd && EvaluatesAsTrue(S, RBop->getRHS())) 7977 return EmitDiagnosticForLogicalAndInLogicalOr(S, OpLoc, RBop); 7978 } 7979 } 7980 } 7981} 7982 7983/// \brief Look for '&&' in the right hand of a '||' expr. 7984static void DiagnoseLogicalAndInLogicalOrRHS(Sema &S, SourceLocation OpLoc, 7985 Expr *LHSExpr, Expr *RHSExpr) { 7986 if (BinaryOperator *Bop = dyn_cast<BinaryOperator>(RHSExpr)) { 7987 if (Bop->getOpcode() == BO_LAnd) { 7988 // If it's "0 || a && b" don't warn since the precedence doesn't matter. 7989 if (EvaluatesAsFalse(S, LHSExpr)) 7990 return; 7991 // If it's "a || b && 1" don't warn since the precedence doesn't matter. 7992 if (!EvaluatesAsTrue(S, Bop->getRHS())) 7993 return EmitDiagnosticForLogicalAndInLogicalOr(S, OpLoc, Bop); 7994 } 7995 } 7996} 7997 7998/// \brief Look for '&' in the left or right hand of a '|' expr. 7999static void DiagnoseBitwiseAndInBitwiseOr(Sema &S, SourceLocation OpLoc, 8000 Expr *OrArg) { 8001 if (BinaryOperator *Bop = dyn_cast<BinaryOperator>(OrArg)) { 8002 if (Bop->getOpcode() == BO_And) 8003 return EmitDiagnosticForBitwiseAndInBitwiseOr(S, OpLoc, Bop); 8004 } 8005} 8006 8007/// DiagnoseBinOpPrecedence - Emit warnings for expressions with tricky 8008/// precedence. 8009static void DiagnoseBinOpPrecedence(Sema &Self, BinaryOperatorKind Opc, 8010 SourceLocation OpLoc, Expr *LHSExpr, 8011 Expr *RHSExpr){ 8012 // Diagnose "arg1 'bitwise' arg2 'eq' arg3". 8013 if (BinaryOperator::isBitwiseOp(Opc)) 8014 DiagnoseBitwisePrecedence(Self, Opc, OpLoc, LHSExpr, RHSExpr); 8015 8016 // Diagnose "arg1 & arg2 | arg3" 8017 if (Opc == BO_Or && !OpLoc.isMacroID()/* Don't warn in macros. */) { 8018 DiagnoseBitwiseAndInBitwiseOr(Self, OpLoc, LHSExpr); 8019 DiagnoseBitwiseAndInBitwiseOr(Self, OpLoc, RHSExpr); 8020 } 8021 8022 // Warn about arg1 || arg2 && arg3, as GCC 4.3+ does. 8023 // We don't warn for 'assert(a || b && "bad")' since this is safe. 8024 if (Opc == BO_LOr && !OpLoc.isMacroID()/* Don't warn in macros. */) { 8025 DiagnoseLogicalAndInLogicalOrLHS(Self, OpLoc, LHSExpr, RHSExpr); 8026 DiagnoseLogicalAndInLogicalOrRHS(Self, OpLoc, LHSExpr, RHSExpr); 8027 } 8028} 8029 8030// Binary Operators. 'Tok' is the token for the operator. 8031ExprResult Sema::ActOnBinOp(Scope *S, SourceLocation TokLoc, 8032 tok::TokenKind Kind, 8033 Expr *LHSExpr, Expr *RHSExpr) { 8034 BinaryOperatorKind Opc = ConvertTokenKindToBinaryOpcode(Kind); 8035 assert((LHSExpr != 0) && "ActOnBinOp(): missing left expression"); 8036 assert((RHSExpr != 0) && "ActOnBinOp(): missing right expression"); 8037 8038 // Emit warnings for tricky precedence issues, e.g. "bitfield & 0x4 == 0" 8039 DiagnoseBinOpPrecedence(*this, Opc, TokLoc, LHSExpr, RHSExpr); 8040 8041 return BuildBinOp(S, TokLoc, Opc, LHSExpr, RHSExpr); 8042} 8043 8044/// Build an overloaded binary operator expression in the given scope. 8045static ExprResult BuildOverloadedBinOp(Sema &S, Scope *Sc, SourceLocation OpLoc, 8046 BinaryOperatorKind Opc, 8047 Expr *LHS, Expr *RHS) { 8048 // Find all of the overloaded operators visible from this 8049 // point. We perform both an operator-name lookup from the local 8050 // scope and an argument-dependent lookup based on the types of 8051 // the arguments. 8052 UnresolvedSet<16> Functions; 8053 OverloadedOperatorKind OverOp 8054 = BinaryOperator::getOverloadedOperator(Opc); 8055 if (Sc && OverOp != OO_None) 8056 S.LookupOverloadedOperatorName(OverOp, Sc, LHS->getType(), 8057 RHS->getType(), Functions); 8058 8059 // Build the (potentially-overloaded, potentially-dependent) 8060 // binary operation. 8061 return S.CreateOverloadedBinOp(OpLoc, Opc, Functions, LHS, RHS); 8062} 8063 8064ExprResult Sema::BuildBinOp(Scope *S, SourceLocation OpLoc, 8065 BinaryOperatorKind Opc, 8066 Expr *LHSExpr, Expr *RHSExpr) { 8067 // We want to end up calling one of checkPseudoObjectAssignment 8068 // (if the LHS is a pseudo-object), BuildOverloadedBinOp (if 8069 // both expressions are overloadable or either is type-dependent), 8070 // or CreateBuiltinBinOp (in any other case). We also want to get 8071 // any placeholder types out of the way. 8072 8073 // Handle pseudo-objects in the LHS. 8074 if (const BuiltinType *pty = LHSExpr->getType()->getAsPlaceholderType()) { 8075 // Assignments with a pseudo-object l-value need special analysis. 8076 if (pty->getKind() == BuiltinType::PseudoObject && 8077 BinaryOperator::isAssignmentOp(Opc)) 8078 return checkPseudoObjectAssignment(S, OpLoc, Opc, LHSExpr, RHSExpr); 8079 8080 // Don't resolve overloads if the other type is overloadable. 8081 if (pty->getKind() == BuiltinType::Overload) { 8082 // We can't actually test that if we still have a placeholder, 8083 // though. Fortunately, none of the exceptions we see in that 8084 // code below are valid when the LHS is an overload set. Note 8085 // that an overload set can be dependently-typed, but it never 8086 // instantiates to having an overloadable type. 8087 ExprResult resolvedRHS = CheckPlaceholderExpr(RHSExpr); 8088 if (resolvedRHS.isInvalid()) return ExprError(); 8089 RHSExpr = resolvedRHS.take(); 8090 8091 if (RHSExpr->isTypeDependent() || 8092 RHSExpr->getType()->isOverloadableType()) 8093 return BuildOverloadedBinOp(*this, S, OpLoc, Opc, LHSExpr, RHSExpr); 8094 } 8095 8096 ExprResult LHS = CheckPlaceholderExpr(LHSExpr); 8097 if (LHS.isInvalid()) return ExprError(); 8098 LHSExpr = LHS.take(); 8099 } 8100 8101 // Handle pseudo-objects in the RHS. 8102 if (const BuiltinType *pty = RHSExpr->getType()->getAsPlaceholderType()) { 8103 // An overload in the RHS can potentially be resolved by the type 8104 // being assigned to. 8105 if (Opc == BO_Assign && pty->getKind() == BuiltinType::Overload) { 8106 if (LHSExpr->isTypeDependent() || RHSExpr->isTypeDependent()) 8107 return BuildOverloadedBinOp(*this, S, OpLoc, Opc, LHSExpr, RHSExpr); 8108 8109 return CreateBuiltinBinOp(OpLoc, Opc, LHSExpr, RHSExpr); 8110 } 8111 8112 // Don't resolve overloads if the other type is overloadable. 8113 if (pty->getKind() == BuiltinType::Overload && 8114 LHSExpr->getType()->isOverloadableType()) 8115 return BuildOverloadedBinOp(*this, S, OpLoc, Opc, LHSExpr, RHSExpr); 8116 8117 ExprResult resolvedRHS = CheckPlaceholderExpr(RHSExpr); 8118 if (!resolvedRHS.isUsable()) return ExprError(); 8119 RHSExpr = resolvedRHS.take(); 8120 } 8121 8122 if (getLangOptions().CPlusPlus) { 8123 // If either expression is type-dependent, always build an 8124 // overloaded op. 8125 if (LHSExpr->isTypeDependent() || RHSExpr->isTypeDependent()) 8126 return BuildOverloadedBinOp(*this, S, OpLoc, Opc, LHSExpr, RHSExpr); 8127 8128 // Otherwise, build an overloaded op if either expression has an 8129 // overloadable type. 8130 if (LHSExpr->getType()->isOverloadableType() || 8131 RHSExpr->getType()->isOverloadableType()) 8132 return BuildOverloadedBinOp(*this, S, OpLoc, Opc, LHSExpr, RHSExpr); 8133 } 8134 8135 // Build a built-in binary operation. 8136 return CreateBuiltinBinOp(OpLoc, Opc, LHSExpr, RHSExpr); 8137} 8138 8139ExprResult Sema::CreateBuiltinUnaryOp(SourceLocation OpLoc, 8140 UnaryOperatorKind Opc, 8141 Expr *InputExpr) { 8142 ExprResult Input = Owned(InputExpr); 8143 ExprValueKind VK = VK_RValue; 8144 ExprObjectKind OK = OK_Ordinary; 8145 QualType resultType; 8146 switch (Opc) { 8147 case UO_PreInc: 8148 case UO_PreDec: 8149 case UO_PostInc: 8150 case UO_PostDec: 8151 resultType = CheckIncrementDecrementOperand(*this, Input.get(), VK, OpLoc, 8152 Opc == UO_PreInc || 8153 Opc == UO_PostInc, 8154 Opc == UO_PreInc || 8155 Opc == UO_PreDec); 8156 break; 8157 case UO_AddrOf: 8158 resultType = CheckAddressOfOperand(*this, Input, OpLoc); 8159 break; 8160 case UO_Deref: { 8161 Input = DefaultFunctionArrayLvalueConversion(Input.take()); 8162 resultType = CheckIndirectionOperand(*this, Input.get(), VK, OpLoc); 8163 break; 8164 } 8165 case UO_Plus: 8166 case UO_Minus: 8167 Input = UsualUnaryConversions(Input.take()); 8168 if (Input.isInvalid()) return ExprError(); 8169 resultType = Input.get()->getType(); 8170 if (resultType->isDependentType()) 8171 break; 8172 if (resultType->isArithmeticType() || // C99 6.5.3.3p1 8173 resultType->isVectorType()) 8174 break; 8175 else if (getLangOptions().CPlusPlus && // C++ [expr.unary.op]p6-7 8176 resultType->isEnumeralType()) 8177 break; 8178 else if (getLangOptions().CPlusPlus && // C++ [expr.unary.op]p6 8179 Opc == UO_Plus && 8180 resultType->isPointerType()) 8181 break; 8182 8183 return ExprError(Diag(OpLoc, diag::err_typecheck_unary_expr) 8184 << resultType << Input.get()->getSourceRange()); 8185 8186 case UO_Not: // bitwise complement 8187 Input = UsualUnaryConversions(Input.take()); 8188 if (Input.isInvalid()) return ExprError(); 8189 resultType = Input.get()->getType(); 8190 if (resultType->isDependentType()) 8191 break; 8192 // C99 6.5.3.3p1. We allow complex int and float as a GCC extension. 8193 if (resultType->isComplexType() || resultType->isComplexIntegerType()) 8194 // C99 does not support '~' for complex conjugation. 8195 Diag(OpLoc, diag::ext_integer_complement_complex) 8196 << resultType << Input.get()->getSourceRange(); 8197 else if (resultType->hasIntegerRepresentation()) 8198 break; 8199 else { 8200 return ExprError(Diag(OpLoc, diag::err_typecheck_unary_expr) 8201 << resultType << Input.get()->getSourceRange()); 8202 } 8203 break; 8204 8205 case UO_LNot: // logical negation 8206 // Unlike +/-/~, integer promotions aren't done here (C99 6.5.3.3p5). 8207 Input = DefaultFunctionArrayLvalueConversion(Input.take()); 8208 if (Input.isInvalid()) return ExprError(); 8209 resultType = Input.get()->getType(); 8210 8211 // Though we still have to promote half FP to float... 8212 if (resultType->isHalfType()) { 8213 Input = ImpCastExprToType(Input.take(), Context.FloatTy, CK_FloatingCast).take(); 8214 resultType = Context.FloatTy; 8215 } 8216 8217 if (resultType->isDependentType()) 8218 break; 8219 if (resultType->isScalarType()) { 8220 // C99 6.5.3.3p1: ok, fallthrough; 8221 if (Context.getLangOptions().CPlusPlus) { 8222 // C++03 [expr.unary.op]p8, C++0x [expr.unary.op]p9: 8223 // operand contextually converted to bool. 8224 Input = ImpCastExprToType(Input.take(), Context.BoolTy, 8225 ScalarTypeToBooleanCastKind(resultType)); 8226 } 8227 } else { 8228 return ExprError(Diag(OpLoc, diag::err_typecheck_unary_expr) 8229 << resultType << Input.get()->getSourceRange()); 8230 } 8231 8232 // LNot always has type int. C99 6.5.3.3p5. 8233 // In C++, it's bool. C++ 5.3.1p8 8234 resultType = Context.getLogicalOperationType(); 8235 break; 8236 case UO_Real: 8237 case UO_Imag: 8238 resultType = CheckRealImagOperand(*this, Input, OpLoc, Opc == UO_Real); 8239 // _Real and _Imag map ordinary l-values into ordinary l-values. 8240 if (Input.isInvalid()) return ExprError(); 8241 if (Input.get()->getValueKind() != VK_RValue && 8242 Input.get()->getObjectKind() == OK_Ordinary) 8243 VK = Input.get()->getValueKind(); 8244 break; 8245 case UO_Extension: 8246 resultType = Input.get()->getType(); 8247 VK = Input.get()->getValueKind(); 8248 OK = Input.get()->getObjectKind(); 8249 break; 8250 } 8251 if (resultType.isNull() || Input.isInvalid()) 8252 return ExprError(); 8253 8254 // Check for array bounds violations in the operand of the UnaryOperator, 8255 // except for the '*' and '&' operators that have to be handled specially 8256 // by CheckArrayAccess (as there are special cases like &array[arraysize] 8257 // that are explicitly defined as valid by the standard). 8258 if (Opc != UO_AddrOf && Opc != UO_Deref) 8259 CheckArrayAccess(Input.get()); 8260 8261 return Owned(new (Context) UnaryOperator(Input.take(), Opc, resultType, 8262 VK, OK, OpLoc)); 8263} 8264 8265/// \brief Determine whether the given expression is a qualified member 8266/// access expression, of a form that could be turned into a pointer to member 8267/// with the address-of operator. 8268static bool isQualifiedMemberAccess(Expr *E) { 8269 if (DeclRefExpr *DRE = dyn_cast<DeclRefExpr>(E)) { 8270 if (!DRE->getQualifier()) 8271 return false; 8272 8273 ValueDecl *VD = DRE->getDecl(); 8274 if (!VD->isCXXClassMember()) 8275 return false; 8276 8277 if (isa<FieldDecl>(VD) || isa<IndirectFieldDecl>(VD)) 8278 return true; 8279 if (CXXMethodDecl *Method = dyn_cast<CXXMethodDecl>(VD)) 8280 return Method->isInstance(); 8281 8282 return false; 8283 } 8284 8285 if (UnresolvedLookupExpr *ULE = dyn_cast<UnresolvedLookupExpr>(E)) { 8286 if (!ULE->getQualifier()) 8287 return false; 8288 8289 for (UnresolvedLookupExpr::decls_iterator D = ULE->decls_begin(), 8290 DEnd = ULE->decls_end(); 8291 D != DEnd; ++D) { 8292 if (CXXMethodDecl *Method = dyn_cast<CXXMethodDecl>(*D)) { 8293 if (Method->isInstance()) 8294 return true; 8295 } else { 8296 // Overload set does not contain methods. 8297 break; 8298 } 8299 } 8300 8301 return false; 8302 } 8303 8304 return false; 8305} 8306 8307ExprResult Sema::BuildUnaryOp(Scope *S, SourceLocation OpLoc, 8308 UnaryOperatorKind Opc, Expr *Input) { 8309 // First things first: handle placeholders so that the 8310 // overloaded-operator check considers the right type. 8311 if (const BuiltinType *pty = Input->getType()->getAsPlaceholderType()) { 8312 // Increment and decrement of pseudo-object references. 8313 if (pty->getKind() == BuiltinType::PseudoObject && 8314 UnaryOperator::isIncrementDecrementOp(Opc)) 8315 return checkPseudoObjectIncDec(S, OpLoc, Opc, Input); 8316 8317 // extension is always a builtin operator. 8318 if (Opc == UO_Extension) 8319 return CreateBuiltinUnaryOp(OpLoc, Opc, Input); 8320 8321 // & gets special logic for several kinds of placeholder. 8322 // The builtin code knows what to do. 8323 if (Opc == UO_AddrOf && 8324 (pty->getKind() == BuiltinType::Overload || 8325 pty->getKind() == BuiltinType::UnknownAny || 8326 pty->getKind() == BuiltinType::BoundMember)) 8327 return CreateBuiltinUnaryOp(OpLoc, Opc, Input); 8328 8329 // Anything else needs to be handled now. 8330 ExprResult Result = CheckPlaceholderExpr(Input); 8331 if (Result.isInvalid()) return ExprError(); 8332 Input = Result.take(); 8333 } 8334 8335 if (getLangOptions().CPlusPlus && Input->getType()->isOverloadableType() && 8336 UnaryOperator::getOverloadedOperator(Opc) != OO_None && 8337 !(Opc == UO_AddrOf && isQualifiedMemberAccess(Input))) { 8338 // Find all of the overloaded operators visible from this 8339 // point. We perform both an operator-name lookup from the local 8340 // scope and an argument-dependent lookup based on the types of 8341 // the arguments. 8342 UnresolvedSet<16> Functions; 8343 OverloadedOperatorKind OverOp = UnaryOperator::getOverloadedOperator(Opc); 8344 if (S && OverOp != OO_None) 8345 LookupOverloadedOperatorName(OverOp, S, Input->getType(), QualType(), 8346 Functions); 8347 8348 return CreateOverloadedUnaryOp(OpLoc, Opc, Functions, Input); 8349 } 8350 8351 return CreateBuiltinUnaryOp(OpLoc, Opc, Input); 8352} 8353 8354// Unary Operators. 'Tok' is the token for the operator. 8355ExprResult Sema::ActOnUnaryOp(Scope *S, SourceLocation OpLoc, 8356 tok::TokenKind Op, Expr *Input) { 8357 return BuildUnaryOp(S, OpLoc, ConvertTokenKindToUnaryOpcode(Op), Input); 8358} 8359 8360/// ActOnAddrLabel - Parse the GNU address of label extension: "&&foo". 8361ExprResult Sema::ActOnAddrLabel(SourceLocation OpLoc, SourceLocation LabLoc, 8362 LabelDecl *TheDecl) { 8363 TheDecl->setUsed(); 8364 // Create the AST node. The address of a label always has type 'void*'. 8365 return Owned(new (Context) AddrLabelExpr(OpLoc, LabLoc, TheDecl, 8366 Context.getPointerType(Context.VoidTy))); 8367} 8368 8369/// Given the last statement in a statement-expression, check whether 8370/// the result is a producing expression (like a call to an 8371/// ns_returns_retained function) and, if so, rebuild it to hoist the 8372/// release out of the full-expression. Otherwise, return null. 8373/// Cannot fail. 8374static Expr *maybeRebuildARCConsumingStmt(Stmt *Statement) { 8375 // Should always be wrapped with one of these. 8376 ExprWithCleanups *cleanups = dyn_cast<ExprWithCleanups>(Statement); 8377 if (!cleanups) return 0; 8378 8379 ImplicitCastExpr *cast = dyn_cast<ImplicitCastExpr>(cleanups->getSubExpr()); 8380 if (!cast || cast->getCastKind() != CK_ARCConsumeObject) 8381 return 0; 8382 8383 // Splice out the cast. This shouldn't modify any interesting 8384 // features of the statement. 8385 Expr *producer = cast->getSubExpr(); 8386 assert(producer->getType() == cast->getType()); 8387 assert(producer->getValueKind() == cast->getValueKind()); 8388 cleanups->setSubExpr(producer); 8389 return cleanups; 8390} 8391 8392ExprResult 8393Sema::ActOnStmtExpr(SourceLocation LPLoc, Stmt *SubStmt, 8394 SourceLocation RPLoc) { // "({..})" 8395 assert(SubStmt && isa<CompoundStmt>(SubStmt) && "Invalid action invocation!"); 8396 CompoundStmt *Compound = cast<CompoundStmt>(SubStmt); 8397 8398 bool isFileScope 8399 = (getCurFunctionOrMethodDecl() == 0) && (getCurBlock() == 0); 8400 if (isFileScope) 8401 return ExprError(Diag(LPLoc, diag::err_stmtexpr_file_scope)); 8402 8403 // FIXME: there are a variety of strange constraints to enforce here, for 8404 // example, it is not possible to goto into a stmt expression apparently. 8405 // More semantic analysis is needed. 8406 8407 // If there are sub stmts in the compound stmt, take the type of the last one 8408 // as the type of the stmtexpr. 8409 QualType Ty = Context.VoidTy; 8410 bool StmtExprMayBindToTemp = false; 8411 if (!Compound->body_empty()) { 8412 Stmt *LastStmt = Compound->body_back(); 8413 LabelStmt *LastLabelStmt = 0; 8414 // If LastStmt is a label, skip down through into the body. 8415 while (LabelStmt *Label = dyn_cast<LabelStmt>(LastStmt)) { 8416 LastLabelStmt = Label; 8417 LastStmt = Label->getSubStmt(); 8418 } 8419 8420 if (Expr *LastE = dyn_cast<Expr>(LastStmt)) { 8421 // Do function/array conversion on the last expression, but not 8422 // lvalue-to-rvalue. However, initialize an unqualified type. 8423 ExprResult LastExpr = DefaultFunctionArrayConversion(LastE); 8424 if (LastExpr.isInvalid()) 8425 return ExprError(); 8426 Ty = LastExpr.get()->getType().getUnqualifiedType(); 8427 8428 if (!Ty->isDependentType() && !LastExpr.get()->isTypeDependent()) { 8429 // In ARC, if the final expression ends in a consume, splice 8430 // the consume out and bind it later. In the alternate case 8431 // (when dealing with a retainable type), the result 8432 // initialization will create a produce. In both cases the 8433 // result will be +1, and we'll need to balance that out with 8434 // a bind. 8435 if (Expr *rebuiltLastStmt 8436 = maybeRebuildARCConsumingStmt(LastExpr.get())) { 8437 LastExpr = rebuiltLastStmt; 8438 } else { 8439 LastExpr = PerformCopyInitialization( 8440 InitializedEntity::InitializeResult(LPLoc, 8441 Ty, 8442 false), 8443 SourceLocation(), 8444 LastExpr); 8445 } 8446 8447 if (LastExpr.isInvalid()) 8448 return ExprError(); 8449 if (LastExpr.get() != 0) { 8450 if (!LastLabelStmt) 8451 Compound->setLastStmt(LastExpr.take()); 8452 else 8453 LastLabelStmt->setSubStmt(LastExpr.take()); 8454 StmtExprMayBindToTemp = true; 8455 } 8456 } 8457 } 8458 } 8459 8460 // FIXME: Check that expression type is complete/non-abstract; statement 8461 // expressions are not lvalues. 8462 Expr *ResStmtExpr = new (Context) StmtExpr(Compound, Ty, LPLoc, RPLoc); 8463 if (StmtExprMayBindToTemp) 8464 return MaybeBindToTemporary(ResStmtExpr); 8465 return Owned(ResStmtExpr); 8466} 8467 8468ExprResult Sema::BuildBuiltinOffsetOf(SourceLocation BuiltinLoc, 8469 TypeSourceInfo *TInfo, 8470 OffsetOfComponent *CompPtr, 8471 unsigned NumComponents, 8472 SourceLocation RParenLoc) { 8473 QualType ArgTy = TInfo->getType(); 8474 bool Dependent = ArgTy->isDependentType(); 8475 SourceRange TypeRange = TInfo->getTypeLoc().getLocalSourceRange(); 8476 8477 // We must have at least one component that refers to the type, and the first 8478 // one is known to be a field designator. Verify that the ArgTy represents 8479 // a struct/union/class. 8480 if (!Dependent && !ArgTy->isRecordType()) 8481 return ExprError(Diag(BuiltinLoc, diag::err_offsetof_record_type) 8482 << ArgTy << TypeRange); 8483 8484 // Type must be complete per C99 7.17p3 because a declaring a variable 8485 // with an incomplete type would be ill-formed. 8486 if (!Dependent 8487 && RequireCompleteType(BuiltinLoc, ArgTy, 8488 PDiag(diag::err_offsetof_incomplete_type) 8489 << TypeRange)) 8490 return ExprError(); 8491 8492 // offsetof with non-identifier designators (e.g. "offsetof(x, a.b[c])") are a 8493 // GCC extension, diagnose them. 8494 // FIXME: This diagnostic isn't actually visible because the location is in 8495 // a system header! 8496 if (NumComponents != 1) 8497 Diag(BuiltinLoc, diag::ext_offsetof_extended_field_designator) 8498 << SourceRange(CompPtr[1].LocStart, CompPtr[NumComponents-1].LocEnd); 8499 8500 bool DidWarnAboutNonPOD = false; 8501 QualType CurrentType = ArgTy; 8502 typedef OffsetOfExpr::OffsetOfNode OffsetOfNode; 8503 SmallVector<OffsetOfNode, 4> Comps; 8504 SmallVector<Expr*, 4> Exprs; 8505 for (unsigned i = 0; i != NumComponents; ++i) { 8506 const OffsetOfComponent &OC = CompPtr[i]; 8507 if (OC.isBrackets) { 8508 // Offset of an array sub-field. TODO: Should we allow vector elements? 8509 if (!CurrentType->isDependentType()) { 8510 const ArrayType *AT = Context.getAsArrayType(CurrentType); 8511 if(!AT) 8512 return ExprError(Diag(OC.LocEnd, diag::err_offsetof_array_type) 8513 << CurrentType); 8514 CurrentType = AT->getElementType(); 8515 } else 8516 CurrentType = Context.DependentTy; 8517 8518 ExprResult IdxRval = DefaultLvalueConversion(static_cast<Expr*>(OC.U.E)); 8519 if (IdxRval.isInvalid()) 8520 return ExprError(); 8521 Expr *Idx = IdxRval.take(); 8522 8523 // The expression must be an integral expression. 8524 // FIXME: An integral constant expression? 8525 if (!Idx->isTypeDependent() && !Idx->isValueDependent() && 8526 !Idx->getType()->isIntegerType()) 8527 return ExprError(Diag(Idx->getLocStart(), 8528 diag::err_typecheck_subscript_not_integer) 8529 << Idx->getSourceRange()); 8530 8531 // Record this array index. 8532 Comps.push_back(OffsetOfNode(OC.LocStart, Exprs.size(), OC.LocEnd)); 8533 Exprs.push_back(Idx); 8534 continue; 8535 } 8536 8537 // Offset of a field. 8538 if (CurrentType->isDependentType()) { 8539 // We have the offset of a field, but we can't look into the dependent 8540 // type. Just record the identifier of the field. 8541 Comps.push_back(OffsetOfNode(OC.LocStart, OC.U.IdentInfo, OC.LocEnd)); 8542 CurrentType = Context.DependentTy; 8543 continue; 8544 } 8545 8546 // We need to have a complete type to look into. 8547 if (RequireCompleteType(OC.LocStart, CurrentType, 8548 diag::err_offsetof_incomplete_type)) 8549 return ExprError(); 8550 8551 // Look for the designated field. 8552 const RecordType *RC = CurrentType->getAs<RecordType>(); 8553 if (!RC) 8554 return ExprError(Diag(OC.LocEnd, diag::err_offsetof_record_type) 8555 << CurrentType); 8556 RecordDecl *RD = RC->getDecl(); 8557 8558 // C++ [lib.support.types]p5: 8559 // The macro offsetof accepts a restricted set of type arguments in this 8560 // International Standard. type shall be a POD structure or a POD union 8561 // (clause 9). 8562 if (CXXRecordDecl *CRD = dyn_cast<CXXRecordDecl>(RD)) { 8563 if (!CRD->isPOD() && !DidWarnAboutNonPOD && 8564 DiagRuntimeBehavior(BuiltinLoc, 0, 8565 PDiag(diag::warn_offsetof_non_pod_type) 8566 << SourceRange(CompPtr[0].LocStart, OC.LocEnd) 8567 << CurrentType)) 8568 DidWarnAboutNonPOD = true; 8569 } 8570 8571 // Look for the field. 8572 LookupResult R(*this, OC.U.IdentInfo, OC.LocStart, LookupMemberName); 8573 LookupQualifiedName(R, RD); 8574 FieldDecl *MemberDecl = R.getAsSingle<FieldDecl>(); 8575 IndirectFieldDecl *IndirectMemberDecl = 0; 8576 if (!MemberDecl) { 8577 if ((IndirectMemberDecl = R.getAsSingle<IndirectFieldDecl>())) 8578 MemberDecl = IndirectMemberDecl->getAnonField(); 8579 } 8580 8581 if (!MemberDecl) 8582 return ExprError(Diag(BuiltinLoc, diag::err_no_member) 8583 << OC.U.IdentInfo << RD << SourceRange(OC.LocStart, 8584 OC.LocEnd)); 8585 8586 // C99 7.17p3: 8587 // (If the specified member is a bit-field, the behavior is undefined.) 8588 // 8589 // We diagnose this as an error. 8590 if (MemberDecl->isBitField()) { 8591 Diag(OC.LocEnd, diag::err_offsetof_bitfield) 8592 << MemberDecl->getDeclName() 8593 << SourceRange(BuiltinLoc, RParenLoc); 8594 Diag(MemberDecl->getLocation(), diag::note_bitfield_decl); 8595 return ExprError(); 8596 } 8597 8598 RecordDecl *Parent = MemberDecl->getParent(); 8599 if (IndirectMemberDecl) 8600 Parent = cast<RecordDecl>(IndirectMemberDecl->getDeclContext()); 8601 8602 // If the member was found in a base class, introduce OffsetOfNodes for 8603 // the base class indirections. 8604 CXXBasePaths Paths(/*FindAmbiguities=*/true, /*RecordPaths=*/true, 8605 /*DetectVirtual=*/false); 8606 if (IsDerivedFrom(CurrentType, Context.getTypeDeclType(Parent), Paths)) { 8607 CXXBasePath &Path = Paths.front(); 8608 for (CXXBasePath::iterator B = Path.begin(), BEnd = Path.end(); 8609 B != BEnd; ++B) 8610 Comps.push_back(OffsetOfNode(B->Base)); 8611 } 8612 8613 if (IndirectMemberDecl) { 8614 for (IndirectFieldDecl::chain_iterator FI = 8615 IndirectMemberDecl->chain_begin(), 8616 FEnd = IndirectMemberDecl->chain_end(); FI != FEnd; FI++) { 8617 assert(isa<FieldDecl>(*FI)); 8618 Comps.push_back(OffsetOfNode(OC.LocStart, 8619 cast<FieldDecl>(*FI), OC.LocEnd)); 8620 } 8621 } else 8622 Comps.push_back(OffsetOfNode(OC.LocStart, MemberDecl, OC.LocEnd)); 8623 8624 CurrentType = MemberDecl->getType().getNonReferenceType(); 8625 } 8626 8627 return Owned(OffsetOfExpr::Create(Context, Context.getSizeType(), BuiltinLoc, 8628 TInfo, Comps.data(), Comps.size(), 8629 Exprs.data(), Exprs.size(), RParenLoc)); 8630} 8631 8632ExprResult Sema::ActOnBuiltinOffsetOf(Scope *S, 8633 SourceLocation BuiltinLoc, 8634 SourceLocation TypeLoc, 8635 ParsedType ParsedArgTy, 8636 OffsetOfComponent *CompPtr, 8637 unsigned NumComponents, 8638 SourceLocation RParenLoc) { 8639 8640 TypeSourceInfo *ArgTInfo; 8641 QualType ArgTy = GetTypeFromParser(ParsedArgTy, &ArgTInfo); 8642 if (ArgTy.isNull()) 8643 return ExprError(); 8644 8645 if (!ArgTInfo) 8646 ArgTInfo = Context.getTrivialTypeSourceInfo(ArgTy, TypeLoc); 8647 8648 return BuildBuiltinOffsetOf(BuiltinLoc, ArgTInfo, CompPtr, NumComponents, 8649 RParenLoc); 8650} 8651 8652 8653ExprResult Sema::ActOnChooseExpr(SourceLocation BuiltinLoc, 8654 Expr *CondExpr, 8655 Expr *LHSExpr, Expr *RHSExpr, 8656 SourceLocation RPLoc) { 8657 assert((CondExpr && LHSExpr && RHSExpr) && "Missing type argument(s)"); 8658 8659 ExprValueKind VK = VK_RValue; 8660 ExprObjectKind OK = OK_Ordinary; 8661 QualType resType; 8662 bool ValueDependent = false; 8663 if (CondExpr->isTypeDependent() || CondExpr->isValueDependent()) { 8664 resType = Context.DependentTy; 8665 ValueDependent = true; 8666 } else { 8667 // The conditional expression is required to be a constant expression. 8668 llvm::APSInt condEval(32); 8669 SourceLocation ExpLoc; 8670 if (!CondExpr->isIntegerConstantExpr(condEval, Context, &ExpLoc)) 8671 return ExprError(Diag(ExpLoc, 8672 diag::err_typecheck_choose_expr_requires_constant) 8673 << CondExpr->getSourceRange()); 8674 8675 // If the condition is > zero, then the AST type is the same as the LSHExpr. 8676 Expr *ActiveExpr = condEval.getZExtValue() ? LHSExpr : RHSExpr; 8677 8678 resType = ActiveExpr->getType(); 8679 ValueDependent = ActiveExpr->isValueDependent(); 8680 VK = ActiveExpr->getValueKind(); 8681 OK = ActiveExpr->getObjectKind(); 8682 } 8683 8684 return Owned(new (Context) ChooseExpr(BuiltinLoc, CondExpr, LHSExpr, RHSExpr, 8685 resType, VK, OK, RPLoc, 8686 resType->isDependentType(), 8687 ValueDependent)); 8688} 8689 8690//===----------------------------------------------------------------------===// 8691// Clang Extensions. 8692//===----------------------------------------------------------------------===// 8693 8694/// ActOnBlockStart - This callback is invoked when a block literal is started. 8695void Sema::ActOnBlockStart(SourceLocation CaretLoc, Scope *CurScope) { 8696 BlockDecl *Block = BlockDecl::Create(Context, CurContext, CaretLoc); 8697 PushBlockScope(CurScope, Block); 8698 CurContext->addDecl(Block); 8699 if (CurScope) 8700 PushDeclContext(CurScope, Block); 8701 else 8702 CurContext = Block; 8703 8704 // Enter a new evaluation context to insulate the block from any 8705 // cleanups from the enclosing full-expression. 8706 PushExpressionEvaluationContext(PotentiallyEvaluated); 8707} 8708 8709void Sema::ActOnBlockArguments(Declarator &ParamInfo, Scope *CurScope) { 8710 assert(ParamInfo.getIdentifier()==0 && "block-id should have no identifier!"); 8711 assert(ParamInfo.getContext() == Declarator::BlockLiteralContext); 8712 BlockScopeInfo *CurBlock = getCurBlock(); 8713 8714 TypeSourceInfo *Sig = GetTypeForDeclarator(ParamInfo, CurScope); 8715 QualType T = Sig->getType(); 8716 8717 // GetTypeForDeclarator always produces a function type for a block 8718 // literal signature. Furthermore, it is always a FunctionProtoType 8719 // unless the function was written with a typedef. 8720 assert(T->isFunctionType() && 8721 "GetTypeForDeclarator made a non-function block signature"); 8722 8723 // Look for an explicit signature in that function type. 8724 FunctionProtoTypeLoc ExplicitSignature; 8725 8726 TypeLoc tmp = Sig->getTypeLoc().IgnoreParens(); 8727 if (isa<FunctionProtoTypeLoc>(tmp)) { 8728 ExplicitSignature = cast<FunctionProtoTypeLoc>(tmp); 8729 8730 // Check whether that explicit signature was synthesized by 8731 // GetTypeForDeclarator. If so, don't save that as part of the 8732 // written signature. 8733 if (ExplicitSignature.getLocalRangeBegin() == 8734 ExplicitSignature.getLocalRangeEnd()) { 8735 // This would be much cheaper if we stored TypeLocs instead of 8736 // TypeSourceInfos. 8737 TypeLoc Result = ExplicitSignature.getResultLoc(); 8738 unsigned Size = Result.getFullDataSize(); 8739 Sig = Context.CreateTypeSourceInfo(Result.getType(), Size); 8740 Sig->getTypeLoc().initializeFullCopy(Result, Size); 8741 8742 ExplicitSignature = FunctionProtoTypeLoc(); 8743 } 8744 } 8745 8746 CurBlock->TheDecl->setSignatureAsWritten(Sig); 8747 CurBlock->FunctionType = T; 8748 8749 const FunctionType *Fn = T->getAs<FunctionType>(); 8750 QualType RetTy = Fn->getResultType(); 8751 bool isVariadic = 8752 (isa<FunctionProtoType>(Fn) && cast<FunctionProtoType>(Fn)->isVariadic()); 8753 8754 CurBlock->TheDecl->setIsVariadic(isVariadic); 8755 8756 // Don't allow returning a objc interface by value. 8757 if (RetTy->isObjCObjectType()) { 8758 Diag(ParamInfo.getSourceRange().getBegin(), 8759 diag::err_object_cannot_be_passed_returned_by_value) << 0 << RetTy; 8760 return; 8761 } 8762 8763 // Context.DependentTy is used as a placeholder for a missing block 8764 // return type. TODO: what should we do with declarators like: 8765 // ^ * { ... } 8766 // If the answer is "apply template argument deduction".... 8767 if (RetTy != Context.DependentTy) { 8768 CurBlock->ReturnType = RetTy; 8769 CurBlock->TheDecl->setBlockMissingReturnType(false); 8770 } 8771 8772 // Push block parameters from the declarator if we had them. 8773 SmallVector<ParmVarDecl*, 8> Params; 8774 if (ExplicitSignature) { 8775 for (unsigned I = 0, E = ExplicitSignature.getNumArgs(); I != E; ++I) { 8776 ParmVarDecl *Param = ExplicitSignature.getArg(I); 8777 if (Param->getIdentifier() == 0 && 8778 !Param->isImplicit() && 8779 !Param->isInvalidDecl() && 8780 !getLangOptions().CPlusPlus) 8781 Diag(Param->getLocation(), diag::err_parameter_name_omitted); 8782 Params.push_back(Param); 8783 } 8784 8785 // Fake up parameter variables if we have a typedef, like 8786 // ^ fntype { ... } 8787 } else if (const FunctionProtoType *Fn = T->getAs<FunctionProtoType>()) { 8788 for (FunctionProtoType::arg_type_iterator 8789 I = Fn->arg_type_begin(), E = Fn->arg_type_end(); I != E; ++I) { 8790 ParmVarDecl *Param = 8791 BuildParmVarDeclForTypedef(CurBlock->TheDecl, 8792 ParamInfo.getSourceRange().getBegin(), 8793 *I); 8794 Params.push_back(Param); 8795 } 8796 } 8797 8798 // Set the parameters on the block decl. 8799 if (!Params.empty()) { 8800 CurBlock->TheDecl->setParams(Params); 8801 CheckParmsForFunctionDef(CurBlock->TheDecl->param_begin(), 8802 CurBlock->TheDecl->param_end(), 8803 /*CheckParameterNames=*/false); 8804 } 8805 8806 // Finally we can process decl attributes. 8807 ProcessDeclAttributes(CurScope, CurBlock->TheDecl, ParamInfo); 8808 8809 if (!isVariadic && CurBlock->TheDecl->getAttr<SentinelAttr>()) { 8810 Diag(ParamInfo.getAttributes()->getLoc(), 8811 diag::warn_attribute_sentinel_not_variadic) << 1; 8812 // FIXME: remove the attribute. 8813 } 8814 8815 // Put the parameter variables in scope. We can bail out immediately 8816 // if we don't have any. 8817 if (Params.empty()) 8818 return; 8819 8820 for (BlockDecl::param_iterator AI = CurBlock->TheDecl->param_begin(), 8821 E = CurBlock->TheDecl->param_end(); AI != E; ++AI) { 8822 (*AI)->setOwningFunction(CurBlock->TheDecl); 8823 8824 // If this has an identifier, add it to the scope stack. 8825 if ((*AI)->getIdentifier()) { 8826 CheckShadow(CurBlock->TheScope, *AI); 8827 8828 PushOnScopeChains(*AI, CurBlock->TheScope); 8829 } 8830 } 8831} 8832 8833/// ActOnBlockError - If there is an error parsing a block, this callback 8834/// is invoked to pop the information about the block from the action impl. 8835void Sema::ActOnBlockError(SourceLocation CaretLoc, Scope *CurScope) { 8836 // Leave the expression-evaluation context. 8837 DiscardCleanupsInEvaluationContext(); 8838 PopExpressionEvaluationContext(); 8839 8840 // Pop off CurBlock, handle nested blocks. 8841 PopDeclContext(); 8842 PopFunctionOrBlockScope(); 8843} 8844 8845/// ActOnBlockStmtExpr - This is called when the body of a block statement 8846/// literal was successfully completed. ^(int x){...} 8847ExprResult Sema::ActOnBlockStmtExpr(SourceLocation CaretLoc, 8848 Stmt *Body, Scope *CurScope) { 8849 // If blocks are disabled, emit an error. 8850 if (!LangOpts.Blocks) 8851 Diag(CaretLoc, diag::err_blocks_disable); 8852 8853 // Leave the expression-evaluation context. 8854 assert(!ExprNeedsCleanups && "cleanups within block not correctly bound!"); 8855 PopExpressionEvaluationContext(); 8856 8857 BlockScopeInfo *BSI = cast<BlockScopeInfo>(FunctionScopes.back()); 8858 8859 PopDeclContext(); 8860 8861 QualType RetTy = Context.VoidTy; 8862 if (!BSI->ReturnType.isNull()) 8863 RetTy = BSI->ReturnType; 8864 8865 bool NoReturn = BSI->TheDecl->getAttr<NoReturnAttr>(); 8866 QualType BlockTy; 8867 8868 // Set the captured variables on the block. 8869 BSI->TheDecl->setCaptures(Context, BSI->Captures.begin(), BSI->Captures.end(), 8870 BSI->CapturesCXXThis); 8871 8872 // If the user wrote a function type in some form, try to use that. 8873 if (!BSI->FunctionType.isNull()) { 8874 const FunctionType *FTy = BSI->FunctionType->getAs<FunctionType>(); 8875 8876 FunctionType::ExtInfo Ext = FTy->getExtInfo(); 8877 if (NoReturn && !Ext.getNoReturn()) Ext = Ext.withNoReturn(true); 8878 8879 // Turn protoless block types into nullary block types. 8880 if (isa<FunctionNoProtoType>(FTy)) { 8881 FunctionProtoType::ExtProtoInfo EPI; 8882 EPI.ExtInfo = Ext; 8883 BlockTy = Context.getFunctionType(RetTy, 0, 0, EPI); 8884 8885 // Otherwise, if we don't need to change anything about the function type, 8886 // preserve its sugar structure. 8887 } else if (FTy->getResultType() == RetTy && 8888 (!NoReturn || FTy->getNoReturnAttr())) { 8889 BlockTy = BSI->FunctionType; 8890 8891 // Otherwise, make the minimal modifications to the function type. 8892 } else { 8893 const FunctionProtoType *FPT = cast<FunctionProtoType>(FTy); 8894 FunctionProtoType::ExtProtoInfo EPI = FPT->getExtProtoInfo(); 8895 EPI.TypeQuals = 0; // FIXME: silently? 8896 EPI.ExtInfo = Ext; 8897 BlockTy = Context.getFunctionType(RetTy, 8898 FPT->arg_type_begin(), 8899 FPT->getNumArgs(), 8900 EPI); 8901 } 8902 8903 // If we don't have a function type, just build one from nothing. 8904 } else { 8905 FunctionProtoType::ExtProtoInfo EPI; 8906 EPI.ExtInfo = FunctionType::ExtInfo().withNoReturn(NoReturn); 8907 BlockTy = Context.getFunctionType(RetTy, 0, 0, EPI); 8908 } 8909 8910 DiagnoseUnusedParameters(BSI->TheDecl->param_begin(), 8911 BSI->TheDecl->param_end()); 8912 BlockTy = Context.getBlockPointerType(BlockTy); 8913 8914 // If needed, diagnose invalid gotos and switches in the block. 8915 if (getCurFunction()->NeedsScopeChecking() && 8916 !hasAnyUnrecoverableErrorsInThisFunction()) 8917 DiagnoseInvalidJumps(cast<CompoundStmt>(Body)); 8918 8919 BSI->TheDecl->setBody(cast<CompoundStmt>(Body)); 8920 8921 for (BlockDecl::capture_const_iterator ci = BSI->TheDecl->capture_begin(), 8922 ce = BSI->TheDecl->capture_end(); ci != ce; ++ci) { 8923 const VarDecl *variable = ci->getVariable(); 8924 QualType T = variable->getType(); 8925 QualType::DestructionKind destructKind = T.isDestructedType(); 8926 if (destructKind != QualType::DK_none) 8927 getCurFunction()->setHasBranchProtectedScope(); 8928 } 8929 8930 computeNRVO(Body, getCurBlock()); 8931 8932 BlockExpr *Result = new (Context) BlockExpr(BSI->TheDecl, BlockTy); 8933 const AnalysisBasedWarnings::Policy &WP = AnalysisWarnings.getDefaultPolicy(); 8934 PopFunctionOrBlockScope(&WP, Result->getBlockDecl(), Result); 8935 8936 // If the block isn't obviously global, i.e. it captures anything at 8937 // all, mark this full-expression as needing a cleanup. 8938 if (Result->getBlockDecl()->hasCaptures()) { 8939 ExprCleanupObjects.push_back(Result->getBlockDecl()); 8940 ExprNeedsCleanups = true; 8941 } 8942 8943 return Owned(Result); 8944} 8945 8946ExprResult Sema::ActOnVAArg(SourceLocation BuiltinLoc, 8947 Expr *E, ParsedType Ty, 8948 SourceLocation RPLoc) { 8949 TypeSourceInfo *TInfo; 8950 GetTypeFromParser(Ty, &TInfo); 8951 return BuildVAArgExpr(BuiltinLoc, E, TInfo, RPLoc); 8952} 8953 8954ExprResult Sema::BuildVAArgExpr(SourceLocation BuiltinLoc, 8955 Expr *E, TypeSourceInfo *TInfo, 8956 SourceLocation RPLoc) { 8957 Expr *OrigExpr = E; 8958 8959 // Get the va_list type 8960 QualType VaListType = Context.getBuiltinVaListType(); 8961 if (VaListType->isArrayType()) { 8962 // Deal with implicit array decay; for example, on x86-64, 8963 // va_list is an array, but it's supposed to decay to 8964 // a pointer for va_arg. 8965 VaListType = Context.getArrayDecayedType(VaListType); 8966 // Make sure the input expression also decays appropriately. 8967 ExprResult Result = UsualUnaryConversions(E); 8968 if (Result.isInvalid()) 8969 return ExprError(); 8970 E = Result.take(); 8971 } else { 8972 // Otherwise, the va_list argument must be an l-value because 8973 // it is modified by va_arg. 8974 if (!E->isTypeDependent() && 8975 CheckForModifiableLvalue(E, BuiltinLoc, *this)) 8976 return ExprError(); 8977 } 8978 8979 if (!E->isTypeDependent() && 8980 !Context.hasSameType(VaListType, E->getType())) { 8981 return ExprError(Diag(E->getLocStart(), 8982 diag::err_first_argument_to_va_arg_not_of_type_va_list) 8983 << OrigExpr->getType() << E->getSourceRange()); 8984 } 8985 8986 if (!TInfo->getType()->isDependentType()) { 8987 if (RequireCompleteType(TInfo->getTypeLoc().getBeginLoc(), TInfo->getType(), 8988 PDiag(diag::err_second_parameter_to_va_arg_incomplete) 8989 << TInfo->getTypeLoc().getSourceRange())) 8990 return ExprError(); 8991 8992 if (RequireNonAbstractType(TInfo->getTypeLoc().getBeginLoc(), 8993 TInfo->getType(), 8994 PDiag(diag::err_second_parameter_to_va_arg_abstract) 8995 << TInfo->getTypeLoc().getSourceRange())) 8996 return ExprError(); 8997 8998 if (!TInfo->getType().isPODType(Context)) { 8999 Diag(TInfo->getTypeLoc().getBeginLoc(), 9000 TInfo->getType()->isObjCLifetimeType() 9001 ? diag::warn_second_parameter_to_va_arg_ownership_qualified 9002 : diag::warn_second_parameter_to_va_arg_not_pod) 9003 << TInfo->getType() 9004 << TInfo->getTypeLoc().getSourceRange(); 9005 } 9006 9007 // Check for va_arg where arguments of the given type will be promoted 9008 // (i.e. this va_arg is guaranteed to have undefined behavior). 9009 QualType PromoteType; 9010 if (TInfo->getType()->isPromotableIntegerType()) { 9011 PromoteType = Context.getPromotedIntegerType(TInfo->getType()); 9012 if (Context.typesAreCompatible(PromoteType, TInfo->getType())) 9013 PromoteType = QualType(); 9014 } 9015 if (TInfo->getType()->isSpecificBuiltinType(BuiltinType::Float)) 9016 PromoteType = Context.DoubleTy; 9017 if (!PromoteType.isNull()) 9018 Diag(TInfo->getTypeLoc().getBeginLoc(), 9019 diag::warn_second_parameter_to_va_arg_never_compatible) 9020 << TInfo->getType() 9021 << PromoteType 9022 << TInfo->getTypeLoc().getSourceRange(); 9023 } 9024 9025 QualType T = TInfo->getType().getNonLValueExprType(Context); 9026 return Owned(new (Context) VAArgExpr(BuiltinLoc, E, TInfo, RPLoc, T)); 9027} 9028 9029ExprResult Sema::ActOnGNUNullExpr(SourceLocation TokenLoc) { 9030 // The type of __null will be int or long, depending on the size of 9031 // pointers on the target. 9032 QualType Ty; 9033 unsigned pw = Context.getTargetInfo().getPointerWidth(0); 9034 if (pw == Context.getTargetInfo().getIntWidth()) 9035 Ty = Context.IntTy; 9036 else if (pw == Context.getTargetInfo().getLongWidth()) 9037 Ty = Context.LongTy; 9038 else if (pw == Context.getTargetInfo().getLongLongWidth()) 9039 Ty = Context.LongLongTy; 9040 else { 9041 llvm_unreachable("I don't know size of pointer!"); 9042 } 9043 9044 return Owned(new (Context) GNUNullExpr(Ty, TokenLoc)); 9045} 9046 9047static void MakeObjCStringLiteralFixItHint(Sema& SemaRef, QualType DstType, 9048 Expr *SrcExpr, FixItHint &Hint) { 9049 if (!SemaRef.getLangOptions().ObjC1) 9050 return; 9051 9052 const ObjCObjectPointerType *PT = DstType->getAs<ObjCObjectPointerType>(); 9053 if (!PT) 9054 return; 9055 9056 // Check if the destination is of type 'id'. 9057 if (!PT->isObjCIdType()) { 9058 // Check if the destination is the 'NSString' interface. 9059 const ObjCInterfaceDecl *ID = PT->getInterfaceDecl(); 9060 if (!ID || !ID->getIdentifier()->isStr("NSString")) 9061 return; 9062 } 9063 9064 // Ignore any parens, implicit casts (should only be 9065 // array-to-pointer decays), and not-so-opaque values. The last is 9066 // important for making this trigger for property assignments. 9067 SrcExpr = SrcExpr->IgnoreParenImpCasts(); 9068 if (OpaqueValueExpr *OV = dyn_cast<OpaqueValueExpr>(SrcExpr)) 9069 if (OV->getSourceExpr()) 9070 SrcExpr = OV->getSourceExpr()->IgnoreParenImpCasts(); 9071 9072 StringLiteral *SL = dyn_cast<StringLiteral>(SrcExpr); 9073 if (!SL || !SL->isAscii()) 9074 return; 9075 9076 Hint = FixItHint::CreateInsertion(SL->getLocStart(), "@"); 9077} 9078 9079bool Sema::DiagnoseAssignmentResult(AssignConvertType ConvTy, 9080 SourceLocation Loc, 9081 QualType DstType, QualType SrcType, 9082 Expr *SrcExpr, AssignmentAction Action, 9083 bool *Complained) { 9084 if (Complained) 9085 *Complained = false; 9086 9087 // Decode the result (notice that AST's are still created for extensions). 9088 bool CheckInferredResultType = false; 9089 bool isInvalid = false; 9090 unsigned DiagKind; 9091 FixItHint Hint; 9092 ConversionFixItGenerator ConvHints; 9093 bool MayHaveConvFixit = false; 9094 bool MayHaveFunctionDiff = false; 9095 9096 switch (ConvTy) { 9097 default: llvm_unreachable("Unknown conversion type"); 9098 case Compatible: return false; 9099 case PointerToInt: 9100 DiagKind = diag::ext_typecheck_convert_pointer_int; 9101 ConvHints.tryToFixConversion(SrcExpr, SrcType, DstType, *this); 9102 MayHaveConvFixit = true; 9103 break; 9104 case IntToPointer: 9105 DiagKind = diag::ext_typecheck_convert_int_pointer; 9106 ConvHints.tryToFixConversion(SrcExpr, SrcType, DstType, *this); 9107 MayHaveConvFixit = true; 9108 break; 9109 case IncompatiblePointer: 9110 MakeObjCStringLiteralFixItHint(*this, DstType, SrcExpr, Hint); 9111 DiagKind = diag::ext_typecheck_convert_incompatible_pointer; 9112 CheckInferredResultType = DstType->isObjCObjectPointerType() && 9113 SrcType->isObjCObjectPointerType(); 9114 if (Hint.isNull() && !CheckInferredResultType) { 9115 ConvHints.tryToFixConversion(SrcExpr, SrcType, DstType, *this); 9116 } 9117 MayHaveConvFixit = true; 9118 break; 9119 case IncompatiblePointerSign: 9120 DiagKind = diag::ext_typecheck_convert_incompatible_pointer_sign; 9121 break; 9122 case FunctionVoidPointer: 9123 DiagKind = diag::ext_typecheck_convert_pointer_void_func; 9124 break; 9125 case IncompatiblePointerDiscardsQualifiers: { 9126 // Perform array-to-pointer decay if necessary. 9127 if (SrcType->isArrayType()) SrcType = Context.getArrayDecayedType(SrcType); 9128 9129 Qualifiers lhq = SrcType->getPointeeType().getQualifiers(); 9130 Qualifiers rhq = DstType->getPointeeType().getQualifiers(); 9131 if (lhq.getAddressSpace() != rhq.getAddressSpace()) { 9132 DiagKind = diag::err_typecheck_incompatible_address_space; 9133 break; 9134 9135 9136 } else if (lhq.getObjCLifetime() != rhq.getObjCLifetime()) { 9137 DiagKind = diag::err_typecheck_incompatible_ownership; 9138 break; 9139 } 9140 9141 llvm_unreachable("unknown error case for discarding qualifiers!"); 9142 // fallthrough 9143 } 9144 case CompatiblePointerDiscardsQualifiers: 9145 // If the qualifiers lost were because we were applying the 9146 // (deprecated) C++ conversion from a string literal to a char* 9147 // (or wchar_t*), then there was no error (C++ 4.2p2). FIXME: 9148 // Ideally, this check would be performed in 9149 // checkPointerTypesForAssignment. However, that would require a 9150 // bit of refactoring (so that the second argument is an 9151 // expression, rather than a type), which should be done as part 9152 // of a larger effort to fix checkPointerTypesForAssignment for 9153 // C++ semantics. 9154 if (getLangOptions().CPlusPlus && 9155 IsStringLiteralToNonConstPointerConversion(SrcExpr, DstType)) 9156 return false; 9157 DiagKind = diag::ext_typecheck_convert_discards_qualifiers; 9158 break; 9159 case IncompatibleNestedPointerQualifiers: 9160 DiagKind = diag::ext_nested_pointer_qualifier_mismatch; 9161 break; 9162 case IntToBlockPointer: 9163 DiagKind = diag::err_int_to_block_pointer; 9164 break; 9165 case IncompatibleBlockPointer: 9166 DiagKind = diag::err_typecheck_convert_incompatible_block_pointer; 9167 break; 9168 case IncompatibleObjCQualifiedId: 9169 // FIXME: Diagnose the problem in ObjCQualifiedIdTypesAreCompatible, since 9170 // it can give a more specific diagnostic. 9171 DiagKind = diag::warn_incompatible_qualified_id; 9172 break; 9173 case IncompatibleVectors: 9174 DiagKind = diag::warn_incompatible_vectors; 9175 break; 9176 case IncompatibleObjCWeakRef: 9177 DiagKind = diag::err_arc_weak_unavailable_assign; 9178 break; 9179 case Incompatible: 9180 DiagKind = diag::err_typecheck_convert_incompatible; 9181 ConvHints.tryToFixConversion(SrcExpr, SrcType, DstType, *this); 9182 MayHaveConvFixit = true; 9183 isInvalid = true; 9184 MayHaveFunctionDiff = true; 9185 break; 9186 } 9187 9188 QualType FirstType, SecondType; 9189 switch (Action) { 9190 case AA_Assigning: 9191 case AA_Initializing: 9192 // The destination type comes first. 9193 FirstType = DstType; 9194 SecondType = SrcType; 9195 break; 9196 9197 case AA_Returning: 9198 case AA_Passing: 9199 case AA_Converting: 9200 case AA_Sending: 9201 case AA_Casting: 9202 // The source type comes first. 9203 FirstType = SrcType; 9204 SecondType = DstType; 9205 break; 9206 } 9207 9208 PartialDiagnostic FDiag = PDiag(DiagKind); 9209 FDiag << FirstType << SecondType << Action << SrcExpr->getSourceRange(); 9210 9211 // If we can fix the conversion, suggest the FixIts. 9212 assert(ConvHints.isNull() || Hint.isNull()); 9213 if (!ConvHints.isNull()) { 9214 for (llvm::SmallVector<FixItHint, 1>::iterator 9215 HI = ConvHints.Hints.begin(), HE = ConvHints.Hints.end(); 9216 HI != HE; ++HI) 9217 FDiag << *HI; 9218 } else { 9219 FDiag << Hint; 9220 } 9221 if (MayHaveConvFixit) { FDiag << (unsigned) (ConvHints.Kind); } 9222 9223 if (MayHaveFunctionDiff) 9224 HandleFunctionTypeMismatch(FDiag, SecondType, FirstType); 9225 9226 Diag(Loc, FDiag); 9227 9228 if (SecondType == Context.OverloadTy) 9229 NoteAllOverloadCandidates(OverloadExpr::find(SrcExpr).Expression, 9230 FirstType); 9231 9232 if (CheckInferredResultType) 9233 EmitRelatedResultTypeNote(SrcExpr); 9234 9235 if (Complained) 9236 *Complained = true; 9237 return isInvalid; 9238} 9239 9240bool Sema::VerifyIntegerConstantExpression(const Expr *E, llvm::APSInt *Result, 9241 unsigned DiagID, bool AllowFold) { 9242 // Circumvent ICE checking in C++11 to avoid evaluating the expression twice 9243 // in the non-ICE case. 9244 if (!getLangOptions().CPlusPlus0x) { 9245 if (E->isIntegerConstantExpr(Context)) { 9246 if (Result) 9247 *Result = E->EvaluateKnownConstInt(Context); 9248 return false; 9249 } 9250 } 9251 9252 Expr::EvalResult EvalResult; 9253 llvm::SmallVector<PartialDiagnosticAt, 8> Notes; 9254 EvalResult.Diag = &Notes; 9255 9256 // Try to evaluate the expression, and produce diagnostics explaining why it's 9257 // not a constant expression as a side-effect. 9258 bool Folded = E->EvaluateAsRValue(EvalResult, Context) && 9259 EvalResult.Val.isInt() && !EvalResult.HasSideEffects; 9260 9261 // In C++11, we can rely on diagnostics being produced for any expression 9262 // which is not a constant expression. If no diagnostics were produced, then 9263 // this is a constant expression. 9264 if (Folded && getLangOptions().CPlusPlus0x && Notes.empty()) { 9265 if (Result) 9266 *Result = EvalResult.Val.getInt(); 9267 return false; 9268 } 9269 9270 if (!Folded || !AllowFold) { 9271 Diag(E->getSourceRange().getBegin(), 9272 DiagID ? DiagID : unsigned(diag::err_expr_not_ice)) 9273 << E->getSourceRange(); 9274 9275 // We only show the notes if they're not the usual "invalid subexpression" 9276 // or if they are actually in a subexpression. 9277 if (Notes.size() != 1 || 9278 Notes[0].second.getDiagID() != diag::note_invalid_subexpr_in_const_expr 9279 || Notes[0].first != E->IgnoreParens()->getExprLoc()) { 9280 for (unsigned I = 0, N = Notes.size(); I != N; ++I) 9281 Diag(Notes[I].first, Notes[I].second); 9282 } 9283 9284 return true; 9285 } 9286 9287 Diag(E->getSourceRange().getBegin(), diag::ext_expr_not_ice) 9288 << E->getSourceRange(); 9289 9290 if (Diags.getDiagnosticLevel(diag::ext_expr_not_ice, E->getExprLoc()) 9291 != DiagnosticsEngine::Ignored) 9292 for (unsigned I = 0, N = Notes.size(); I != N; ++I) 9293 Diag(Notes[I].first, Notes[I].second); 9294 9295 if (Result) 9296 *Result = EvalResult.Val.getInt(); 9297 return false; 9298} 9299 9300void 9301Sema::PushExpressionEvaluationContext(ExpressionEvaluationContext NewContext) { 9302 ExprEvalContexts.push_back( 9303 ExpressionEvaluationContextRecord(NewContext, 9304 ExprCleanupObjects.size(), 9305 ExprNeedsCleanups)); 9306 ExprNeedsCleanups = false; 9307} 9308 9309void Sema::PopExpressionEvaluationContext() { 9310 // Pop the current expression evaluation context off the stack. 9311 ExpressionEvaluationContextRecord Rec = ExprEvalContexts.back(); 9312 ExprEvalContexts.pop_back(); 9313 9314 if (Rec.Context == PotentiallyPotentiallyEvaluated) { 9315 if (Rec.PotentiallyReferenced) { 9316 // Mark any remaining declarations in the current position of the stack 9317 // as "referenced". If they were not meant to be referenced, semantic 9318 // analysis would have eliminated them (e.g., in ActOnCXXTypeId). 9319 for (PotentiallyReferencedDecls::iterator 9320 I = Rec.PotentiallyReferenced->begin(), 9321 IEnd = Rec.PotentiallyReferenced->end(); 9322 I != IEnd; ++I) 9323 MarkDeclarationReferenced(I->first, I->second); 9324 } 9325 9326 if (Rec.PotentiallyDiagnosed) { 9327 // Emit any pending diagnostics. 9328 for (PotentiallyEmittedDiagnostics::iterator 9329 I = Rec.PotentiallyDiagnosed->begin(), 9330 IEnd = Rec.PotentiallyDiagnosed->end(); 9331 I != IEnd; ++I) 9332 Diag(I->first, I->second); 9333 } 9334 } 9335 9336 // When are coming out of an unevaluated context, clear out any 9337 // temporaries that we may have created as part of the evaluation of 9338 // the expression in that context: they aren't relevant because they 9339 // will never be constructed. 9340 if (Rec.Context == Unevaluated || Rec.Context == ConstantEvaluated) { 9341 ExprCleanupObjects.erase(ExprCleanupObjects.begin() + Rec.NumCleanupObjects, 9342 ExprCleanupObjects.end()); 9343 ExprNeedsCleanups = Rec.ParentNeedsCleanups; 9344 9345 // Otherwise, merge the contexts together. 9346 } else { 9347 ExprNeedsCleanups |= Rec.ParentNeedsCleanups; 9348 } 9349 9350 // Destroy the popped expression evaluation record. 9351 Rec.Destroy(); 9352} 9353 9354void Sema::DiscardCleanupsInEvaluationContext() { 9355 ExprCleanupObjects.erase( 9356 ExprCleanupObjects.begin() + ExprEvalContexts.back().NumCleanupObjects, 9357 ExprCleanupObjects.end()); 9358 ExprNeedsCleanups = false; 9359} 9360 9361/// \brief Note that the given declaration was referenced in the source code. 9362/// 9363/// This routine should be invoke whenever a given declaration is referenced 9364/// in the source code, and where that reference occurred. If this declaration 9365/// reference means that the the declaration is used (C++ [basic.def.odr]p2, 9366/// C99 6.9p3), then the declaration will be marked as used. 9367/// 9368/// \param Loc the location where the declaration was referenced. 9369/// 9370/// \param D the declaration that has been referenced by the source code. 9371void Sema::MarkDeclarationReferenced(SourceLocation Loc, Decl *D) { 9372 assert(D && "No declaration?"); 9373 9374 D->setReferenced(); 9375 9376 if (D->isUsed(false)) 9377 return; 9378 9379 // Mark a parameter or variable declaration "used", regardless of whether 9380 // we're in a template or not. The reason for this is that unevaluated 9381 // expressions (e.g. (void)sizeof()) constitute a use for warning purposes 9382 // (-Wunused-variables and -Wunused-parameters) 9383 if (isa<ParmVarDecl>(D) || 9384 (isa<VarDecl>(D) && D->getDeclContext()->isFunctionOrMethod())) { 9385 D->setUsed(); 9386 return; 9387 } 9388 9389 if (!isa<VarDecl>(D) && !isa<FunctionDecl>(D)) 9390 return; 9391 9392 // Do not mark anything as "used" within a dependent context; wait for 9393 // an instantiation. 9394 if (CurContext->isDependentContext()) 9395 return; 9396 9397 switch (ExprEvalContexts.back().Context) { 9398 case Unevaluated: 9399 // We are in an expression that is not potentially evaluated; do nothing. 9400 return; 9401 9402 case ConstantEvaluated: 9403 // We are in an expression that will be evaluated during translation; in 9404 // C++11, we need to define any functions which are used in case they're 9405 // constexpr, whereas in C++98, we only need to define static data members 9406 // of class templates. 9407 if (!getLangOptions().CPlusPlus || 9408 (!getLangOptions().CPlusPlus0x && !isa<VarDecl>(D))) 9409 return; 9410 break; 9411 9412 case PotentiallyEvaluated: 9413 // We are in a potentially-evaluated expression, so this declaration is 9414 // "used"; handle this below. 9415 break; 9416 9417 case PotentiallyPotentiallyEvaluated: 9418 // We are in an expression that may be potentially evaluated; queue this 9419 // declaration reference until we know whether the expression is 9420 // potentially evaluated. 9421 ExprEvalContexts.back().addReferencedDecl(Loc, D); 9422 return; 9423 9424 case PotentiallyEvaluatedIfUsed: 9425 // Referenced declarations will only be used if the construct in the 9426 // containing expression is used. 9427 return; 9428 } 9429 9430 // Note that this declaration has been used. 9431 if (CXXConstructorDecl *Constructor = dyn_cast<CXXConstructorDecl>(D)) { 9432 if (Constructor->isDefaulted()) { 9433 if (Constructor->isDefaultConstructor()) { 9434 if (Constructor->isTrivial()) 9435 return; 9436 if (!Constructor->isUsed(false)) 9437 DefineImplicitDefaultConstructor(Loc, Constructor); 9438 } else if (Constructor->isCopyConstructor()) { 9439 if (!Constructor->isUsed(false)) 9440 DefineImplicitCopyConstructor(Loc, Constructor); 9441 } else if (Constructor->isMoveConstructor()) { 9442 if (!Constructor->isUsed(false)) 9443 DefineImplicitMoveConstructor(Loc, Constructor); 9444 } 9445 } 9446 9447 MarkVTableUsed(Loc, Constructor->getParent()); 9448 } else if (CXXDestructorDecl *Destructor = dyn_cast<CXXDestructorDecl>(D)) { 9449 if (Destructor->isDefaulted() && !Destructor->isUsed(false)) 9450 DefineImplicitDestructor(Loc, Destructor); 9451 if (Destructor->isVirtual()) 9452 MarkVTableUsed(Loc, Destructor->getParent()); 9453 } else if (CXXMethodDecl *MethodDecl = dyn_cast<CXXMethodDecl>(D)) { 9454 if (MethodDecl->isDefaulted() && MethodDecl->isOverloadedOperator() && 9455 MethodDecl->getOverloadedOperator() == OO_Equal) { 9456 if (!MethodDecl->isUsed(false)) { 9457 if (MethodDecl->isCopyAssignmentOperator()) 9458 DefineImplicitCopyAssignment(Loc, MethodDecl); 9459 else 9460 DefineImplicitMoveAssignment(Loc, MethodDecl); 9461 } 9462 } else if (MethodDecl->isVirtual()) 9463 MarkVTableUsed(Loc, MethodDecl->getParent()); 9464 } 9465 if (FunctionDecl *Function = dyn_cast<FunctionDecl>(D)) { 9466 // Recursive functions should be marked when used from another function. 9467 if (CurContext == Function) return; 9468 9469 // Implicit instantiation of function templates and member functions of 9470 // class templates. 9471 if (Function->isImplicitlyInstantiable()) { 9472 bool AlreadyInstantiated = false; 9473 if (FunctionTemplateSpecializationInfo *SpecInfo 9474 = Function->getTemplateSpecializationInfo()) { 9475 if (SpecInfo->getPointOfInstantiation().isInvalid()) 9476 SpecInfo->setPointOfInstantiation(Loc); 9477 else if (SpecInfo->getTemplateSpecializationKind() 9478 == TSK_ImplicitInstantiation) 9479 AlreadyInstantiated = true; 9480 } else if (MemberSpecializationInfo *MSInfo 9481 = Function->getMemberSpecializationInfo()) { 9482 if (MSInfo->getPointOfInstantiation().isInvalid()) 9483 MSInfo->setPointOfInstantiation(Loc); 9484 else if (MSInfo->getTemplateSpecializationKind() 9485 == TSK_ImplicitInstantiation) 9486 AlreadyInstantiated = true; 9487 } 9488 9489 if (!AlreadyInstantiated) { 9490 if (isa<CXXRecordDecl>(Function->getDeclContext()) && 9491 cast<CXXRecordDecl>(Function->getDeclContext())->isLocalClass()) 9492 PendingLocalImplicitInstantiations.push_back(std::make_pair(Function, 9493 Loc)); 9494 else 9495 PendingInstantiations.push_back(std::make_pair(Function, Loc)); 9496 } 9497 } else { 9498 // Walk redefinitions, as some of them may be instantiable. 9499 for (FunctionDecl::redecl_iterator i(Function->redecls_begin()), 9500 e(Function->redecls_end()); i != e; ++i) { 9501 if (!i->isUsed(false) && i->isImplicitlyInstantiable()) 9502 MarkDeclarationReferenced(Loc, *i); 9503 } 9504 } 9505 9506 // Keep track of used but undefined functions. 9507 if (!Function->isPure() && !Function->hasBody() && 9508 Function->getLinkage() != ExternalLinkage) { 9509 SourceLocation &old = UndefinedInternals[Function->getCanonicalDecl()]; 9510 if (old.isInvalid()) old = Loc; 9511 } 9512 9513 Function->setUsed(true); 9514 return; 9515 } 9516 9517 if (VarDecl *Var = dyn_cast<VarDecl>(D)) { 9518 // Implicit instantiation of static data members of class templates. 9519 if (Var->isStaticDataMember() && 9520 Var->getInstantiatedFromStaticDataMember()) { 9521 MemberSpecializationInfo *MSInfo = Var->getMemberSpecializationInfo(); 9522 assert(MSInfo && "Missing member specialization information?"); 9523 if (MSInfo->getPointOfInstantiation().isInvalid() && 9524 MSInfo->getTemplateSpecializationKind()== TSK_ImplicitInstantiation) { 9525 MSInfo->setPointOfInstantiation(Loc); 9526 // This is a modification of an existing AST node. Notify listeners. 9527 if (ASTMutationListener *L = getASTMutationListener()) 9528 L->StaticDataMemberInstantiated(Var); 9529 QualType T = Var->getType(); 9530 if (T.isConstQualified() && !T.isVolatileQualified() && 9531 T->isIntegralOrEnumerationType()) 9532 InstantiateStaticDataMemberDefinition(Loc, Var); 9533 else 9534 PendingInstantiations.push_back(std::make_pair(Var, Loc)); 9535 } 9536 } 9537 9538 // Keep track of used but undefined variables. We make a hole in 9539 // the warning for static const data members with in-line 9540 // initializers. 9541 if (Var->hasDefinition() == VarDecl::DeclarationOnly 9542 && Var->getLinkage() != ExternalLinkage 9543 && !(Var->isStaticDataMember() && Var->hasInit())) { 9544 SourceLocation &old = UndefinedInternals[Var->getCanonicalDecl()]; 9545 if (old.isInvalid()) old = Loc; 9546 } 9547 9548 D->setUsed(true); 9549 return; 9550 } 9551} 9552 9553namespace { 9554 // Mark all of the declarations referenced 9555 // FIXME: Not fully implemented yet! We need to have a better understanding 9556 // of when we're entering 9557 class MarkReferencedDecls : public RecursiveASTVisitor<MarkReferencedDecls> { 9558 Sema &S; 9559 SourceLocation Loc; 9560 9561 public: 9562 typedef RecursiveASTVisitor<MarkReferencedDecls> Inherited; 9563 9564 MarkReferencedDecls(Sema &S, SourceLocation Loc) : S(S), Loc(Loc) { } 9565 9566 bool TraverseTemplateArgument(const TemplateArgument &Arg); 9567 bool TraverseRecordType(RecordType *T); 9568 }; 9569} 9570 9571bool MarkReferencedDecls::TraverseTemplateArgument( 9572 const TemplateArgument &Arg) { 9573 if (Arg.getKind() == TemplateArgument::Declaration) { 9574 S.MarkDeclarationReferenced(Loc, Arg.getAsDecl()); 9575 } 9576 9577 return Inherited::TraverseTemplateArgument(Arg); 9578} 9579 9580bool MarkReferencedDecls::TraverseRecordType(RecordType *T) { 9581 if (ClassTemplateSpecializationDecl *Spec 9582 = dyn_cast<ClassTemplateSpecializationDecl>(T->getDecl())) { 9583 const TemplateArgumentList &Args = Spec->getTemplateArgs(); 9584 return TraverseTemplateArguments(Args.data(), Args.size()); 9585 } 9586 9587 return true; 9588} 9589 9590void Sema::MarkDeclarationsReferencedInType(SourceLocation Loc, QualType T) { 9591 MarkReferencedDecls Marker(*this, Loc); 9592 Marker.TraverseType(Context.getCanonicalType(T)); 9593} 9594 9595namespace { 9596 /// \brief Helper class that marks all of the declarations referenced by 9597 /// potentially-evaluated subexpressions as "referenced". 9598 class EvaluatedExprMarker : public EvaluatedExprVisitor<EvaluatedExprMarker> { 9599 Sema &S; 9600 9601 public: 9602 typedef EvaluatedExprVisitor<EvaluatedExprMarker> Inherited; 9603 9604 explicit EvaluatedExprMarker(Sema &S) : Inherited(S.Context), S(S) { } 9605 9606 void VisitDeclRefExpr(DeclRefExpr *E) { 9607 S.MarkDeclarationReferenced(E->getLocation(), E->getDecl()); 9608 } 9609 9610 void VisitMemberExpr(MemberExpr *E) { 9611 S.MarkDeclarationReferenced(E->getMemberLoc(), E->getMemberDecl()); 9612 Inherited::VisitMemberExpr(E); 9613 } 9614 9615 void VisitCXXBindTemporaryExpr(CXXBindTemporaryExpr *E) { 9616 S.MarkDeclarationReferenced(E->getLocStart(), 9617 const_cast<CXXDestructorDecl*>(E->getTemporary()->getDestructor())); 9618 Visit(E->getSubExpr()); 9619 } 9620 9621 void VisitCXXNewExpr(CXXNewExpr *E) { 9622 if (E->getConstructor()) 9623 S.MarkDeclarationReferenced(E->getLocStart(), E->getConstructor()); 9624 if (E->getOperatorNew()) 9625 S.MarkDeclarationReferenced(E->getLocStart(), E->getOperatorNew()); 9626 if (E->getOperatorDelete()) 9627 S.MarkDeclarationReferenced(E->getLocStart(), E->getOperatorDelete()); 9628 Inherited::VisitCXXNewExpr(E); 9629 } 9630 9631 void VisitCXXDeleteExpr(CXXDeleteExpr *E) { 9632 if (E->getOperatorDelete()) 9633 S.MarkDeclarationReferenced(E->getLocStart(), E->getOperatorDelete()); 9634 QualType Destroyed = S.Context.getBaseElementType(E->getDestroyedType()); 9635 if (const RecordType *DestroyedRec = Destroyed->getAs<RecordType>()) { 9636 CXXRecordDecl *Record = cast<CXXRecordDecl>(DestroyedRec->getDecl()); 9637 S.MarkDeclarationReferenced(E->getLocStart(), 9638 S.LookupDestructor(Record)); 9639 } 9640 9641 Inherited::VisitCXXDeleteExpr(E); 9642 } 9643 9644 void VisitCXXConstructExpr(CXXConstructExpr *E) { 9645 S.MarkDeclarationReferenced(E->getLocStart(), E->getConstructor()); 9646 Inherited::VisitCXXConstructExpr(E); 9647 } 9648 9649 void VisitBlockDeclRefExpr(BlockDeclRefExpr *E) { 9650 S.MarkDeclarationReferenced(E->getLocation(), E->getDecl()); 9651 } 9652 9653 void VisitCXXDefaultArgExpr(CXXDefaultArgExpr *E) { 9654 Visit(E->getExpr()); 9655 } 9656 }; 9657} 9658 9659/// \brief Mark any declarations that appear within this expression or any 9660/// potentially-evaluated subexpressions as "referenced". 9661void Sema::MarkDeclarationsReferencedInExpr(Expr *E) { 9662 EvaluatedExprMarker(*this).Visit(E); 9663} 9664 9665/// \brief Emit a diagnostic that describes an effect on the run-time behavior 9666/// of the program being compiled. 9667/// 9668/// This routine emits the given diagnostic when the code currently being 9669/// type-checked is "potentially evaluated", meaning that there is a 9670/// possibility that the code will actually be executable. Code in sizeof() 9671/// expressions, code used only during overload resolution, etc., are not 9672/// potentially evaluated. This routine will suppress such diagnostics or, 9673/// in the absolutely nutty case of potentially potentially evaluated 9674/// expressions (C++ typeid), queue the diagnostic to potentially emit it 9675/// later. 9676/// 9677/// This routine should be used for all diagnostics that describe the run-time 9678/// behavior of a program, such as passing a non-POD value through an ellipsis. 9679/// Failure to do so will likely result in spurious diagnostics or failures 9680/// during overload resolution or within sizeof/alignof/typeof/typeid. 9681bool Sema::DiagRuntimeBehavior(SourceLocation Loc, const Stmt *Statement, 9682 const PartialDiagnostic &PD) { 9683 switch (ExprEvalContexts.back().Context) { 9684 case Unevaluated: 9685 // The argument will never be evaluated, so don't complain. 9686 break; 9687 9688 case ConstantEvaluated: 9689 // Relevant diagnostics should be produced by constant evaluation. 9690 break; 9691 9692 case PotentiallyEvaluated: 9693 case PotentiallyEvaluatedIfUsed: 9694 if (Statement && getCurFunctionOrMethodDecl()) { 9695 FunctionScopes.back()->PossiblyUnreachableDiags. 9696 push_back(sema::PossiblyUnreachableDiag(PD, Loc, Statement)); 9697 } 9698 else 9699 Diag(Loc, PD); 9700 9701 return true; 9702 9703 case PotentiallyPotentiallyEvaluated: 9704 ExprEvalContexts.back().addDiagnostic(Loc, PD); 9705 break; 9706 } 9707 9708 return false; 9709} 9710 9711bool Sema::CheckCallReturnType(QualType ReturnType, SourceLocation Loc, 9712 CallExpr *CE, FunctionDecl *FD) { 9713 if (ReturnType->isVoidType() || !ReturnType->isIncompleteType()) 9714 return false; 9715 9716 PartialDiagnostic Note = 9717 FD ? PDiag(diag::note_function_with_incomplete_return_type_declared_here) 9718 << FD->getDeclName() : PDiag(); 9719 SourceLocation NoteLoc = FD ? FD->getLocation() : SourceLocation(); 9720 9721 if (RequireCompleteType(Loc, ReturnType, 9722 FD ? 9723 PDiag(diag::err_call_function_incomplete_return) 9724 << CE->getSourceRange() << FD->getDeclName() : 9725 PDiag(diag::err_call_incomplete_return) 9726 << CE->getSourceRange(), 9727 std::make_pair(NoteLoc, Note))) 9728 return true; 9729 9730 return false; 9731} 9732 9733// Diagnose the s/=/==/ and s/\|=/!=/ typos. Note that adding parentheses 9734// will prevent this condition from triggering, which is what we want. 9735void Sema::DiagnoseAssignmentAsCondition(Expr *E) { 9736 SourceLocation Loc; 9737 9738 unsigned diagnostic = diag::warn_condition_is_assignment; 9739 bool IsOrAssign = false; 9740 9741 if (BinaryOperator *Op = dyn_cast<BinaryOperator>(E)) { 9742 if (Op->getOpcode() != BO_Assign && Op->getOpcode() != BO_OrAssign) 9743 return; 9744 9745 IsOrAssign = Op->getOpcode() == BO_OrAssign; 9746 9747 // Greylist some idioms by putting them into a warning subcategory. 9748 if (ObjCMessageExpr *ME 9749 = dyn_cast<ObjCMessageExpr>(Op->getRHS()->IgnoreParenCasts())) { 9750 Selector Sel = ME->getSelector(); 9751 9752 // self = [<foo> init...] 9753 if (isSelfExpr(Op->getLHS()) && Sel.getNameForSlot(0).startswith("init")) 9754 diagnostic = diag::warn_condition_is_idiomatic_assignment; 9755 9756 // <foo> = [<bar> nextObject] 9757 else if (Sel.isUnarySelector() && Sel.getNameForSlot(0) == "nextObject") 9758 diagnostic = diag::warn_condition_is_idiomatic_assignment; 9759 } 9760 9761 Loc = Op->getOperatorLoc(); 9762 } else if (CXXOperatorCallExpr *Op = dyn_cast<CXXOperatorCallExpr>(E)) { 9763 if (Op->getOperator() != OO_Equal && Op->getOperator() != OO_PipeEqual) 9764 return; 9765 9766 IsOrAssign = Op->getOperator() == OO_PipeEqual; 9767 Loc = Op->getOperatorLoc(); 9768 } else { 9769 // Not an assignment. 9770 return; 9771 } 9772 9773 Diag(Loc, diagnostic) << E->getSourceRange(); 9774 9775 SourceLocation Open = E->getSourceRange().getBegin(); 9776 SourceLocation Close = PP.getLocForEndOfToken(E->getSourceRange().getEnd()); 9777 Diag(Loc, diag::note_condition_assign_silence) 9778 << FixItHint::CreateInsertion(Open, "(") 9779 << FixItHint::CreateInsertion(Close, ")"); 9780 9781 if (IsOrAssign) 9782 Diag(Loc, diag::note_condition_or_assign_to_comparison) 9783 << FixItHint::CreateReplacement(Loc, "!="); 9784 else 9785 Diag(Loc, diag::note_condition_assign_to_comparison) 9786 << FixItHint::CreateReplacement(Loc, "=="); 9787} 9788 9789/// \brief Redundant parentheses over an equality comparison can indicate 9790/// that the user intended an assignment used as condition. 9791void Sema::DiagnoseEqualityWithExtraParens(ParenExpr *ParenE) { 9792 // Don't warn if the parens came from a macro. 9793 SourceLocation parenLoc = ParenE->getLocStart(); 9794 if (parenLoc.isInvalid() || parenLoc.isMacroID()) 9795 return; 9796 // Don't warn for dependent expressions. 9797 if (ParenE->isTypeDependent()) 9798 return; 9799 9800 Expr *E = ParenE->IgnoreParens(); 9801 9802 if (BinaryOperator *opE = dyn_cast<BinaryOperator>(E)) 9803 if (opE->getOpcode() == BO_EQ && 9804 opE->getLHS()->IgnoreParenImpCasts()->isModifiableLvalue(Context) 9805 == Expr::MLV_Valid) { 9806 SourceLocation Loc = opE->getOperatorLoc(); 9807 9808 Diag(Loc, diag::warn_equality_with_extra_parens) << E->getSourceRange(); 9809 Diag(Loc, diag::note_equality_comparison_silence) 9810 << FixItHint::CreateRemoval(ParenE->getSourceRange().getBegin()) 9811 << FixItHint::CreateRemoval(ParenE->getSourceRange().getEnd()); 9812 Diag(Loc, diag::note_equality_comparison_to_assign) 9813 << FixItHint::CreateReplacement(Loc, "="); 9814 } 9815} 9816 9817ExprResult Sema::CheckBooleanCondition(Expr *E, SourceLocation Loc) { 9818 DiagnoseAssignmentAsCondition(E); 9819 if (ParenExpr *parenE = dyn_cast<ParenExpr>(E)) 9820 DiagnoseEqualityWithExtraParens(parenE); 9821 9822 ExprResult result = CheckPlaceholderExpr(E); 9823 if (result.isInvalid()) return ExprError(); 9824 E = result.take(); 9825 9826 if (!E->isTypeDependent()) { 9827 if (getLangOptions().CPlusPlus) 9828 return CheckCXXBooleanCondition(E); // C++ 6.4p4 9829 9830 ExprResult ERes = DefaultFunctionArrayLvalueConversion(E); 9831 if (ERes.isInvalid()) 9832 return ExprError(); 9833 E = ERes.take(); 9834 9835 QualType T = E->getType(); 9836 if (!T->isScalarType()) { // C99 6.8.4.1p1 9837 Diag(Loc, diag::err_typecheck_statement_requires_scalar) 9838 << T << E->getSourceRange(); 9839 return ExprError(); 9840 } 9841 } 9842 9843 return Owned(E); 9844} 9845 9846ExprResult Sema::ActOnBooleanCondition(Scope *S, SourceLocation Loc, 9847 Expr *SubExpr) { 9848 if (!SubExpr) 9849 return ExprError(); 9850 9851 return CheckBooleanCondition(SubExpr, Loc); 9852} 9853 9854namespace { 9855 /// A visitor for rebuilding a call to an __unknown_any expression 9856 /// to have an appropriate type. 9857 struct RebuildUnknownAnyFunction 9858 : StmtVisitor<RebuildUnknownAnyFunction, ExprResult> { 9859 9860 Sema &S; 9861 9862 RebuildUnknownAnyFunction(Sema &S) : S(S) {} 9863 9864 ExprResult VisitStmt(Stmt *S) { 9865 llvm_unreachable("unexpected statement!"); 9866 return ExprError(); 9867 } 9868 9869 ExprResult VisitExpr(Expr *E) { 9870 S.Diag(E->getExprLoc(), diag::err_unsupported_unknown_any_call) 9871 << E->getSourceRange(); 9872 return ExprError(); 9873 } 9874 9875 /// Rebuild an expression which simply semantically wraps another 9876 /// expression which it shares the type and value kind of. 9877 template <class T> ExprResult rebuildSugarExpr(T *E) { 9878 ExprResult SubResult = Visit(E->getSubExpr()); 9879 if (SubResult.isInvalid()) return ExprError(); 9880 9881 Expr *SubExpr = SubResult.take(); 9882 E->setSubExpr(SubExpr); 9883 E->setType(SubExpr->getType()); 9884 E->setValueKind(SubExpr->getValueKind()); 9885 assert(E->getObjectKind() == OK_Ordinary); 9886 return E; 9887 } 9888 9889 ExprResult VisitParenExpr(ParenExpr *E) { 9890 return rebuildSugarExpr(E); 9891 } 9892 9893 ExprResult VisitUnaryExtension(UnaryOperator *E) { 9894 return rebuildSugarExpr(E); 9895 } 9896 9897 ExprResult VisitUnaryAddrOf(UnaryOperator *E) { 9898 ExprResult SubResult = Visit(E->getSubExpr()); 9899 if (SubResult.isInvalid()) return ExprError(); 9900 9901 Expr *SubExpr = SubResult.take(); 9902 E->setSubExpr(SubExpr); 9903 E->setType(S.Context.getPointerType(SubExpr->getType())); 9904 assert(E->getValueKind() == VK_RValue); 9905 assert(E->getObjectKind() == OK_Ordinary); 9906 return E; 9907 } 9908 9909 ExprResult resolveDecl(Expr *E, ValueDecl *VD) { 9910 if (!isa<FunctionDecl>(VD)) return VisitExpr(E); 9911 9912 E->setType(VD->getType()); 9913 9914 assert(E->getValueKind() == VK_RValue); 9915 if (S.getLangOptions().CPlusPlus && 9916 !(isa<CXXMethodDecl>(VD) && 9917 cast<CXXMethodDecl>(VD)->isInstance())) 9918 E->setValueKind(VK_LValue); 9919 9920 return E; 9921 } 9922 9923 ExprResult VisitMemberExpr(MemberExpr *E) { 9924 return resolveDecl(E, E->getMemberDecl()); 9925 } 9926 9927 ExprResult VisitDeclRefExpr(DeclRefExpr *E) { 9928 return resolveDecl(E, E->getDecl()); 9929 } 9930 }; 9931} 9932 9933/// Given a function expression of unknown-any type, try to rebuild it 9934/// to have a function type. 9935static ExprResult rebuildUnknownAnyFunction(Sema &S, Expr *FunctionExpr) { 9936 ExprResult Result = RebuildUnknownAnyFunction(S).Visit(FunctionExpr); 9937 if (Result.isInvalid()) return ExprError(); 9938 return S.DefaultFunctionArrayConversion(Result.take()); 9939} 9940 9941namespace { 9942 /// A visitor for rebuilding an expression of type __unknown_anytype 9943 /// into one which resolves the type directly on the referring 9944 /// expression. Strict preservation of the original source 9945 /// structure is not a goal. 9946 struct RebuildUnknownAnyExpr 9947 : StmtVisitor<RebuildUnknownAnyExpr, ExprResult> { 9948 9949 Sema &S; 9950 9951 /// The current destination type. 9952 QualType DestType; 9953 9954 RebuildUnknownAnyExpr(Sema &S, QualType CastType) 9955 : S(S), DestType(CastType) {} 9956 9957 ExprResult VisitStmt(Stmt *S) { 9958 llvm_unreachable("unexpected statement!"); 9959 return ExprError(); 9960 } 9961 9962 ExprResult VisitExpr(Expr *E) { 9963 S.Diag(E->getExprLoc(), diag::err_unsupported_unknown_any_expr) 9964 << E->getSourceRange(); 9965 return ExprError(); 9966 } 9967 9968 ExprResult VisitCallExpr(CallExpr *E); 9969 ExprResult VisitObjCMessageExpr(ObjCMessageExpr *E); 9970 9971 /// Rebuild an expression which simply semantically wraps another 9972 /// expression which it shares the type and value kind of. 9973 template <class T> ExprResult rebuildSugarExpr(T *E) { 9974 ExprResult SubResult = Visit(E->getSubExpr()); 9975 if (SubResult.isInvalid()) return ExprError(); 9976 Expr *SubExpr = SubResult.take(); 9977 E->setSubExpr(SubExpr); 9978 E->setType(SubExpr->getType()); 9979 E->setValueKind(SubExpr->getValueKind()); 9980 assert(E->getObjectKind() == OK_Ordinary); 9981 return E; 9982 } 9983 9984 ExprResult VisitParenExpr(ParenExpr *E) { 9985 return rebuildSugarExpr(E); 9986 } 9987 9988 ExprResult VisitUnaryExtension(UnaryOperator *E) { 9989 return rebuildSugarExpr(E); 9990 } 9991 9992 ExprResult VisitUnaryAddrOf(UnaryOperator *E) { 9993 const PointerType *Ptr = DestType->getAs<PointerType>(); 9994 if (!Ptr) { 9995 S.Diag(E->getOperatorLoc(), diag::err_unknown_any_addrof) 9996 << E->getSourceRange(); 9997 return ExprError(); 9998 } 9999 assert(E->getValueKind() == VK_RValue); 10000 assert(E->getObjectKind() == OK_Ordinary); 10001 E->setType(DestType); 10002 10003 // Build the sub-expression as if it were an object of the pointee type. 10004 DestType = Ptr->getPointeeType(); 10005 ExprResult SubResult = Visit(E->getSubExpr()); 10006 if (SubResult.isInvalid()) return ExprError(); 10007 E->setSubExpr(SubResult.take()); 10008 return E; 10009 } 10010 10011 ExprResult VisitImplicitCastExpr(ImplicitCastExpr *E); 10012 10013 ExprResult resolveDecl(Expr *E, ValueDecl *VD); 10014 10015 ExprResult VisitMemberExpr(MemberExpr *E) { 10016 return resolveDecl(E, E->getMemberDecl()); 10017 } 10018 10019 ExprResult VisitDeclRefExpr(DeclRefExpr *E) { 10020 return resolveDecl(E, E->getDecl()); 10021 } 10022 }; 10023} 10024 10025/// Rebuilds a call expression which yielded __unknown_anytype. 10026ExprResult RebuildUnknownAnyExpr::VisitCallExpr(CallExpr *E) { 10027 Expr *CalleeExpr = E->getCallee(); 10028 10029 enum FnKind { 10030 FK_MemberFunction, 10031 FK_FunctionPointer, 10032 FK_BlockPointer 10033 }; 10034 10035 FnKind Kind; 10036 QualType CalleeType = CalleeExpr->getType(); 10037 if (CalleeType == S.Context.BoundMemberTy) { 10038 assert(isa<CXXMemberCallExpr>(E) || isa<CXXOperatorCallExpr>(E)); 10039 Kind = FK_MemberFunction; 10040 CalleeType = Expr::findBoundMemberType(CalleeExpr); 10041 } else if (const PointerType *Ptr = CalleeType->getAs<PointerType>()) { 10042 CalleeType = Ptr->getPointeeType(); 10043 Kind = FK_FunctionPointer; 10044 } else { 10045 CalleeType = CalleeType->castAs<BlockPointerType>()->getPointeeType(); 10046 Kind = FK_BlockPointer; 10047 } 10048 const FunctionType *FnType = CalleeType->castAs<FunctionType>(); 10049 10050 // Verify that this is a legal result type of a function. 10051 if (DestType->isArrayType() || DestType->isFunctionType()) { 10052 unsigned diagID = diag::err_func_returning_array_function; 10053 if (Kind == FK_BlockPointer) 10054 diagID = diag::err_block_returning_array_function; 10055 10056 S.Diag(E->getExprLoc(), diagID) 10057 << DestType->isFunctionType() << DestType; 10058 return ExprError(); 10059 } 10060 10061 // Otherwise, go ahead and set DestType as the call's result. 10062 E->setType(DestType.getNonLValueExprType(S.Context)); 10063 E->setValueKind(Expr::getValueKindForType(DestType)); 10064 assert(E->getObjectKind() == OK_Ordinary); 10065 10066 // Rebuild the function type, replacing the result type with DestType. 10067 if (const FunctionProtoType *Proto = dyn_cast<FunctionProtoType>(FnType)) 10068 DestType = S.Context.getFunctionType(DestType, 10069 Proto->arg_type_begin(), 10070 Proto->getNumArgs(), 10071 Proto->getExtProtoInfo()); 10072 else 10073 DestType = S.Context.getFunctionNoProtoType(DestType, 10074 FnType->getExtInfo()); 10075 10076 // Rebuild the appropriate pointer-to-function type. 10077 switch (Kind) { 10078 case FK_MemberFunction: 10079 // Nothing to do. 10080 break; 10081 10082 case FK_FunctionPointer: 10083 DestType = S.Context.getPointerType(DestType); 10084 break; 10085 10086 case FK_BlockPointer: 10087 DestType = S.Context.getBlockPointerType(DestType); 10088 break; 10089 } 10090 10091 // Finally, we can recurse. 10092 ExprResult CalleeResult = Visit(CalleeExpr); 10093 if (!CalleeResult.isUsable()) return ExprError(); 10094 E->setCallee(CalleeResult.take()); 10095 10096 // Bind a temporary if necessary. 10097 return S.MaybeBindToTemporary(E); 10098} 10099 10100ExprResult RebuildUnknownAnyExpr::VisitObjCMessageExpr(ObjCMessageExpr *E) { 10101 // Verify that this is a legal result type of a call. 10102 if (DestType->isArrayType() || DestType->isFunctionType()) { 10103 S.Diag(E->getExprLoc(), diag::err_func_returning_array_function) 10104 << DestType->isFunctionType() << DestType; 10105 return ExprError(); 10106 } 10107 10108 // Rewrite the method result type if available. 10109 if (ObjCMethodDecl *Method = E->getMethodDecl()) { 10110 assert(Method->getResultType() == S.Context.UnknownAnyTy); 10111 Method->setResultType(DestType); 10112 } 10113 10114 // Change the type of the message. 10115 E->setType(DestType.getNonReferenceType()); 10116 E->setValueKind(Expr::getValueKindForType(DestType)); 10117 10118 return S.MaybeBindToTemporary(E); 10119} 10120 10121ExprResult RebuildUnknownAnyExpr::VisitImplicitCastExpr(ImplicitCastExpr *E) { 10122 // The only case we should ever see here is a function-to-pointer decay. 10123 assert(E->getCastKind() == CK_FunctionToPointerDecay); 10124 assert(E->getValueKind() == VK_RValue); 10125 assert(E->getObjectKind() == OK_Ordinary); 10126 10127 E->setType(DestType); 10128 10129 // Rebuild the sub-expression as the pointee (function) type. 10130 DestType = DestType->castAs<PointerType>()->getPointeeType(); 10131 10132 ExprResult Result = Visit(E->getSubExpr()); 10133 if (!Result.isUsable()) return ExprError(); 10134 10135 E->setSubExpr(Result.take()); 10136 return S.Owned(E); 10137} 10138 10139ExprResult RebuildUnknownAnyExpr::resolveDecl(Expr *E, ValueDecl *VD) { 10140 ExprValueKind ValueKind = VK_LValue; 10141 QualType Type = DestType; 10142 10143 // We know how to make this work for certain kinds of decls: 10144 10145 // - functions 10146 if (FunctionDecl *FD = dyn_cast<FunctionDecl>(VD)) { 10147 if (const PointerType *Ptr = Type->getAs<PointerType>()) { 10148 DestType = Ptr->getPointeeType(); 10149 ExprResult Result = resolveDecl(E, VD); 10150 if (Result.isInvalid()) return ExprError(); 10151 return S.ImpCastExprToType(Result.take(), Type, 10152 CK_FunctionToPointerDecay, VK_RValue); 10153 } 10154 10155 if (!Type->isFunctionType()) { 10156 S.Diag(E->getExprLoc(), diag::err_unknown_any_function) 10157 << VD << E->getSourceRange(); 10158 return ExprError(); 10159 } 10160 10161 if (CXXMethodDecl *MD = dyn_cast<CXXMethodDecl>(FD)) 10162 if (MD->isInstance()) { 10163 ValueKind = VK_RValue; 10164 Type = S.Context.BoundMemberTy; 10165 } 10166 10167 // Function references aren't l-values in C. 10168 if (!S.getLangOptions().CPlusPlus) 10169 ValueKind = VK_RValue; 10170 10171 // - variables 10172 } else if (isa<VarDecl>(VD)) { 10173 if (const ReferenceType *RefTy = Type->getAs<ReferenceType>()) { 10174 Type = RefTy->getPointeeType(); 10175 } else if (Type->isFunctionType()) { 10176 S.Diag(E->getExprLoc(), diag::err_unknown_any_var_function_type) 10177 << VD << E->getSourceRange(); 10178 return ExprError(); 10179 } 10180 10181 // - nothing else 10182 } else { 10183 S.Diag(E->getExprLoc(), diag::err_unsupported_unknown_any_decl) 10184 << VD << E->getSourceRange(); 10185 return ExprError(); 10186 } 10187 10188 VD->setType(DestType); 10189 E->setType(Type); 10190 E->setValueKind(ValueKind); 10191 return S.Owned(E); 10192} 10193 10194/// Check a cast of an unknown-any type. We intentionally only 10195/// trigger this for C-style casts. 10196ExprResult Sema::checkUnknownAnyCast(SourceRange TypeRange, QualType CastType, 10197 Expr *CastExpr, CastKind &CastKind, 10198 ExprValueKind &VK, CXXCastPath &Path) { 10199 // Rewrite the casted expression from scratch. 10200 ExprResult result = RebuildUnknownAnyExpr(*this, CastType).Visit(CastExpr); 10201 if (!result.isUsable()) return ExprError(); 10202 10203 CastExpr = result.take(); 10204 VK = CastExpr->getValueKind(); 10205 CastKind = CK_NoOp; 10206 10207 return CastExpr; 10208} 10209 10210ExprResult Sema::forceUnknownAnyToType(Expr *E, QualType ToType) { 10211 return RebuildUnknownAnyExpr(*this, ToType).Visit(E); 10212} 10213 10214static ExprResult diagnoseUnknownAnyExpr(Sema &S, Expr *E) { 10215 Expr *orig = E; 10216 unsigned diagID = diag::err_uncasted_use_of_unknown_any; 10217 while (true) { 10218 E = E->IgnoreParenImpCasts(); 10219 if (CallExpr *call = dyn_cast<CallExpr>(E)) { 10220 E = call->getCallee(); 10221 diagID = diag::err_uncasted_call_of_unknown_any; 10222 } else { 10223 break; 10224 } 10225 } 10226 10227 SourceLocation loc; 10228 NamedDecl *d; 10229 if (DeclRefExpr *ref = dyn_cast<DeclRefExpr>(E)) { 10230 loc = ref->getLocation(); 10231 d = ref->getDecl(); 10232 } else if (MemberExpr *mem = dyn_cast<MemberExpr>(E)) { 10233 loc = mem->getMemberLoc(); 10234 d = mem->getMemberDecl(); 10235 } else if (ObjCMessageExpr *msg = dyn_cast<ObjCMessageExpr>(E)) { 10236 diagID = diag::err_uncasted_call_of_unknown_any; 10237 loc = msg->getSelectorStartLoc(); 10238 d = msg->getMethodDecl(); 10239 if (!d) { 10240 S.Diag(loc, diag::err_uncasted_send_to_unknown_any_method) 10241 << static_cast<unsigned>(msg->isClassMessage()) << msg->getSelector() 10242 << orig->getSourceRange(); 10243 return ExprError(); 10244 } 10245 } else { 10246 S.Diag(E->getExprLoc(), diag::err_unsupported_unknown_any_expr) 10247 << E->getSourceRange(); 10248 return ExprError(); 10249 } 10250 10251 S.Diag(loc, diagID) << d << orig->getSourceRange(); 10252 10253 // Never recoverable. 10254 return ExprError(); 10255} 10256 10257/// Check for operands with placeholder types and complain if found. 10258/// Returns true if there was an error and no recovery was possible. 10259ExprResult Sema::CheckPlaceholderExpr(Expr *E) { 10260 const BuiltinType *placeholderType = E->getType()->getAsPlaceholderType(); 10261 if (!placeholderType) return Owned(E); 10262 10263 switch (placeholderType->getKind()) { 10264 10265 // Overloaded expressions. 10266 case BuiltinType::Overload: { 10267 // Try to resolve a single function template specialization. 10268 // This is obligatory. 10269 ExprResult result = Owned(E); 10270 if (ResolveAndFixSingleFunctionTemplateSpecialization(result, false)) { 10271 return result; 10272 10273 // If that failed, try to recover with a call. 10274 } else { 10275 tryToRecoverWithCall(result, PDiag(diag::err_ovl_unresolvable), 10276 /*complain*/ true); 10277 return result; 10278 } 10279 } 10280 10281 // Bound member functions. 10282 case BuiltinType::BoundMember: { 10283 ExprResult result = Owned(E); 10284 tryToRecoverWithCall(result, PDiag(diag::err_bound_member_function), 10285 /*complain*/ true); 10286 return result; 10287 } 10288 10289 // ARC unbridged casts. 10290 case BuiltinType::ARCUnbridgedCast: { 10291 Expr *realCast = stripARCUnbridgedCast(E); 10292 diagnoseARCUnbridgedCast(realCast); 10293 return Owned(realCast); 10294 } 10295 10296 // Expressions of unknown type. 10297 case BuiltinType::UnknownAny: 10298 return diagnoseUnknownAnyExpr(*this, E); 10299 10300 // Pseudo-objects. 10301 case BuiltinType::PseudoObject: 10302 return checkPseudoObjectRValue(E); 10303 10304 // Everything else should be impossible. 10305#define BUILTIN_TYPE(Id, SingletonId) \ 10306 case BuiltinType::Id: 10307#define PLACEHOLDER_TYPE(Id, SingletonId) 10308#include "clang/AST/BuiltinTypes.def" 10309 break; 10310 } 10311 10312 llvm_unreachable("invalid placeholder type!"); 10313} 10314 10315bool Sema::CheckCaseExpression(Expr *E) { 10316 if (E->isTypeDependent()) 10317 return true; 10318 if (E->isValueDependent() || E->isIntegerConstantExpr(Context)) 10319 return E->getType()->isIntegralOrEnumerationType(); 10320 return false; 10321} 10322