SemaExpr.cpp revision d2008e2c80d6c9282044ec873a937a17a0f33579
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/DelayedDiagnostic.h" 16#include "clang/Sema/Initialization.h" 17#include "clang/Sema/Lookup.h" 18#include "clang/Sema/ScopeInfo.h" 19#include "clang/Sema/AnalysisBasedWarnings.h" 20#include "clang/AST/ASTContext.h" 21#include "clang/AST/ASTConsumer.h" 22#include "clang/AST/ASTMutationListener.h" 23#include "clang/AST/CXXInheritance.h" 24#include "clang/AST/DeclObjC.h" 25#include "clang/AST/DeclTemplate.h" 26#include "clang/AST/EvaluatedExprVisitor.h" 27#include "clang/AST/Expr.h" 28#include "clang/AST/ExprCXX.h" 29#include "clang/AST/ExprObjC.h" 30#include "clang/AST/RecursiveASTVisitor.h" 31#include "clang/AST/TypeLoc.h" 32#include "clang/Basic/PartialDiagnostic.h" 33#include "clang/Basic/SourceManager.h" 34#include "clang/Basic/TargetInfo.h" 35#include "clang/Lex/LiteralSupport.h" 36#include "clang/Lex/Preprocessor.h" 37#include "clang/Sema/DeclSpec.h" 38#include "clang/Sema/Designator.h" 39#include "clang/Sema/Scope.h" 40#include "clang/Sema/ScopeInfo.h" 41#include "clang/Sema/ParsedTemplate.h" 42#include "clang/Sema/SemaFixItUtils.h" 43#include "clang/Sema/Template.h" 44#include "TreeTransform.h" 45using namespace clang; 46using namespace sema; 47 48/// \brief Determine whether the use of this declaration is valid, without 49/// emitting diagnostics. 50bool Sema::CanUseDecl(NamedDecl *D) { 51 // See if this is an auto-typed variable whose initializer we are parsing. 52 if (ParsingInitForAutoVars.count(D)) 53 return false; 54 55 // See if this is a deleted function. 56 if (FunctionDecl *FD = dyn_cast<FunctionDecl>(D)) { 57 if (FD->isDeleted()) 58 return false; 59 } 60 61 // See if this function is unavailable. 62 if (D->getAvailability() == AR_Unavailable && 63 cast<Decl>(CurContext)->getAvailability() != AR_Unavailable) 64 return false; 65 66 return true; 67} 68 69static AvailabilityResult DiagnoseAvailabilityOfDecl(Sema &S, 70 NamedDecl *D, SourceLocation Loc, 71 const ObjCInterfaceDecl *UnknownObjCClass) { 72 // See if this declaration is unavailable or deprecated. 73 std::string Message; 74 AvailabilityResult Result = D->getAvailability(&Message); 75 if (const EnumConstantDecl *ECD = dyn_cast<EnumConstantDecl>(D)) 76 if (Result == AR_Available) { 77 const DeclContext *DC = ECD->getDeclContext(); 78 if (const EnumDecl *TheEnumDecl = dyn_cast<EnumDecl>(DC)) 79 Result = TheEnumDecl->getAvailability(&Message); 80 } 81 82 switch (Result) { 83 case AR_Available: 84 case AR_NotYetIntroduced: 85 break; 86 87 case AR_Deprecated: 88 S.EmitDeprecationWarning(D, Message, Loc, UnknownObjCClass); 89 break; 90 91 case AR_Unavailable: 92 if (S.getCurContextAvailability() != AR_Unavailable) { 93 if (Message.empty()) { 94 if (!UnknownObjCClass) 95 S.Diag(Loc, diag::err_unavailable) << D->getDeclName(); 96 else 97 S.Diag(Loc, diag::warn_unavailable_fwdclass_message) 98 << D->getDeclName(); 99 } 100 else 101 S.Diag(Loc, diag::err_unavailable_message) 102 << D->getDeclName() << Message; 103 S.Diag(D->getLocation(), diag::note_unavailable_here) 104 << isa<FunctionDecl>(D) << false; 105 } 106 break; 107 } 108 return Result; 109} 110 111/// \brief Emit a note explaining that this function is deleted or unavailable. 112void Sema::NoteDeletedFunction(FunctionDecl *Decl) { 113 CXXMethodDecl *Method = dyn_cast<CXXMethodDecl>(Decl); 114 115 if (Method && Method->isDeleted() && !Method->isDeletedAsWritten()) { 116 // If the method was explicitly defaulted, point at that declaration. 117 if (!Method->isImplicit()) 118 Diag(Decl->getLocation(), diag::note_implicitly_deleted); 119 120 // Try to diagnose why this special member function was implicitly 121 // deleted. This might fail, if that reason no longer applies. 122 CXXSpecialMember CSM = getSpecialMember(Method); 123 if (CSM != CXXInvalid) 124 ShouldDeleteSpecialMember(Method, CSM, /*Diagnose=*/true); 125 126 return; 127 } 128 129 Diag(Decl->getLocation(), diag::note_unavailable_here) 130 << 1 << Decl->isDeleted(); 131} 132 133/// \brief Determine whether the use of this declaration is valid, and 134/// emit any corresponding diagnostics. 135/// 136/// This routine diagnoses various problems with referencing 137/// declarations that can occur when using a declaration. For example, 138/// it might warn if a deprecated or unavailable declaration is being 139/// used, or produce an error (and return true) if a C++0x deleted 140/// function is being used. 141/// 142/// \returns true if there was an error (this declaration cannot be 143/// referenced), false otherwise. 144/// 145bool Sema::DiagnoseUseOfDecl(NamedDecl *D, SourceLocation Loc, 146 const ObjCInterfaceDecl *UnknownObjCClass) { 147 if (getLangOpts().CPlusPlus && isa<FunctionDecl>(D)) { 148 // If there were any diagnostics suppressed by template argument deduction, 149 // emit them now. 150 llvm::DenseMap<Decl *, SmallVector<PartialDiagnosticAt, 1> >::iterator 151 Pos = SuppressedDiagnostics.find(D->getCanonicalDecl()); 152 if (Pos != SuppressedDiagnostics.end()) { 153 SmallVectorImpl<PartialDiagnosticAt> &Suppressed = Pos->second; 154 for (unsigned I = 0, N = Suppressed.size(); I != N; ++I) 155 Diag(Suppressed[I].first, Suppressed[I].second); 156 157 // Clear out the list of suppressed diagnostics, so that we don't emit 158 // them again for this specialization. However, we don't obsolete this 159 // entry from the table, because we want to avoid ever emitting these 160 // diagnostics again. 161 Suppressed.clear(); 162 } 163 } 164 165 // See if this is an auto-typed variable whose initializer we are parsing. 166 if (ParsingInitForAutoVars.count(D)) { 167 Diag(Loc, diag::err_auto_variable_cannot_appear_in_own_initializer) 168 << D->getDeclName(); 169 return true; 170 } 171 172 // See if this is a deleted function. 173 if (FunctionDecl *FD = dyn_cast<FunctionDecl>(D)) { 174 if (FD->isDeleted()) { 175 Diag(Loc, diag::err_deleted_function_use); 176 NoteDeletedFunction(FD); 177 return true; 178 } 179 } 180 DiagnoseAvailabilityOfDecl(*this, D, Loc, UnknownObjCClass); 181 182 // Warn if this is used but marked unused. 183 if (D->hasAttr<UnusedAttr>()) 184 Diag(Loc, diag::warn_used_but_marked_unused) << D->getDeclName(); 185 return false; 186} 187 188/// \brief Retrieve the message suffix that should be added to a 189/// diagnostic complaining about the given function being deleted or 190/// unavailable. 191std::string Sema::getDeletedOrUnavailableSuffix(const FunctionDecl *FD) { 192 // FIXME: C++0x implicitly-deleted special member functions could be 193 // detected here so that we could improve diagnostics to say, e.g., 194 // "base class 'A' had a deleted copy constructor". 195 if (FD->isDeleted()) 196 return std::string(); 197 198 std::string Message; 199 if (FD->getAvailability(&Message)) 200 return ": " + Message; 201 202 return std::string(); 203} 204 205/// DiagnoseSentinelCalls - This routine checks whether a call or 206/// message-send is to a declaration with the sentinel attribute, and 207/// if so, it checks that the requirements of the sentinel are 208/// satisfied. 209void Sema::DiagnoseSentinelCalls(NamedDecl *D, SourceLocation Loc, 210 Expr **args, unsigned numArgs) { 211 const SentinelAttr *attr = D->getAttr<SentinelAttr>(); 212 if (!attr) 213 return; 214 215 // The number of formal parameters of the declaration. 216 unsigned numFormalParams; 217 218 // The kind of declaration. This is also an index into a %select in 219 // the diagnostic. 220 enum CalleeType { CT_Function, CT_Method, CT_Block } calleeType; 221 222 if (ObjCMethodDecl *MD = dyn_cast<ObjCMethodDecl>(D)) { 223 numFormalParams = MD->param_size(); 224 calleeType = CT_Method; 225 } else if (FunctionDecl *FD = dyn_cast<FunctionDecl>(D)) { 226 numFormalParams = FD->param_size(); 227 calleeType = CT_Function; 228 } else if (isa<VarDecl>(D)) { 229 QualType type = cast<ValueDecl>(D)->getType(); 230 const FunctionType *fn = 0; 231 if (const PointerType *ptr = type->getAs<PointerType>()) { 232 fn = ptr->getPointeeType()->getAs<FunctionType>(); 233 if (!fn) return; 234 calleeType = CT_Function; 235 } else if (const BlockPointerType *ptr = type->getAs<BlockPointerType>()) { 236 fn = ptr->getPointeeType()->castAs<FunctionType>(); 237 calleeType = CT_Block; 238 } else { 239 return; 240 } 241 242 if (const FunctionProtoType *proto = dyn_cast<FunctionProtoType>(fn)) { 243 numFormalParams = proto->getNumArgs(); 244 } else { 245 numFormalParams = 0; 246 } 247 } else { 248 return; 249 } 250 251 // "nullPos" is the number of formal parameters at the end which 252 // effectively count as part of the variadic arguments. This is 253 // useful if you would prefer to not have *any* formal parameters, 254 // but the language forces you to have at least one. 255 unsigned nullPos = attr->getNullPos(); 256 assert((nullPos == 0 || nullPos == 1) && "invalid null position on sentinel"); 257 numFormalParams = (nullPos > numFormalParams ? 0 : numFormalParams - nullPos); 258 259 // The number of arguments which should follow the sentinel. 260 unsigned numArgsAfterSentinel = attr->getSentinel(); 261 262 // If there aren't enough arguments for all the formal parameters, 263 // the sentinel, and the args after the sentinel, complain. 264 if (numArgs < numFormalParams + numArgsAfterSentinel + 1) { 265 Diag(Loc, diag::warn_not_enough_argument) << D->getDeclName(); 266 Diag(D->getLocation(), diag::note_sentinel_here) << calleeType; 267 return; 268 } 269 270 // Otherwise, find the sentinel expression. 271 Expr *sentinelExpr = args[numArgs - numArgsAfterSentinel - 1]; 272 if (!sentinelExpr) return; 273 if (sentinelExpr->isValueDependent()) return; 274 if (Context.isSentinelNullExpr(sentinelExpr)) return; 275 276 // Pick a reasonable string to insert. Optimistically use 'nil' or 277 // 'NULL' if those are actually defined in the context. Only use 278 // 'nil' for ObjC methods, where it's much more likely that the 279 // variadic arguments form a list of object pointers. 280 SourceLocation MissingNilLoc 281 = PP.getLocForEndOfToken(sentinelExpr->getLocEnd()); 282 std::string NullValue; 283 if (calleeType == CT_Method && 284 PP.getIdentifierInfo("nil")->hasMacroDefinition()) 285 NullValue = "nil"; 286 else if (PP.getIdentifierInfo("NULL")->hasMacroDefinition()) 287 NullValue = "NULL"; 288 else 289 NullValue = "(void*) 0"; 290 291 if (MissingNilLoc.isInvalid()) 292 Diag(Loc, diag::warn_missing_sentinel) << calleeType; 293 else 294 Diag(MissingNilLoc, diag::warn_missing_sentinel) 295 << calleeType 296 << FixItHint::CreateInsertion(MissingNilLoc, ", " + NullValue); 297 Diag(D->getLocation(), diag::note_sentinel_here) << calleeType; 298} 299 300SourceRange Sema::getExprRange(Expr *E) const { 301 return E ? E->getSourceRange() : SourceRange(); 302} 303 304//===----------------------------------------------------------------------===// 305// Standard Promotions and Conversions 306//===----------------------------------------------------------------------===// 307 308/// DefaultFunctionArrayConversion (C99 6.3.2.1p3, C99 6.3.2.1p4). 309ExprResult Sema::DefaultFunctionArrayConversion(Expr *E) { 310 // Handle any placeholder expressions which made it here. 311 if (E->getType()->isPlaceholderType()) { 312 ExprResult result = CheckPlaceholderExpr(E); 313 if (result.isInvalid()) return ExprError(); 314 E = result.take(); 315 } 316 317 QualType Ty = E->getType(); 318 assert(!Ty.isNull() && "DefaultFunctionArrayConversion - missing type"); 319 320 if (Ty->isFunctionType()) 321 E = ImpCastExprToType(E, Context.getPointerType(Ty), 322 CK_FunctionToPointerDecay).take(); 323 else if (Ty->isArrayType()) { 324 // In C90 mode, arrays only promote to pointers if the array expression is 325 // an lvalue. The relevant legalese is C90 6.2.2.1p3: "an lvalue that has 326 // type 'array of type' is converted to an expression that has type 'pointer 327 // to type'...". In C99 this was changed to: C99 6.3.2.1p3: "an expression 328 // that has type 'array of type' ...". The relevant change is "an lvalue" 329 // (C90) to "an expression" (C99). 330 // 331 // C++ 4.2p1: 332 // An lvalue or rvalue of type "array of N T" or "array of unknown bound of 333 // T" can be converted to an rvalue of type "pointer to T". 334 // 335 if (getLangOpts().C99 || getLangOpts().CPlusPlus || E->isLValue()) 336 E = ImpCastExprToType(E, Context.getArrayDecayedType(Ty), 337 CK_ArrayToPointerDecay).take(); 338 } 339 return Owned(E); 340} 341 342static void CheckForNullPointerDereference(Sema &S, Expr *E) { 343 // Check to see if we are dereferencing a null pointer. If so, 344 // and if not volatile-qualified, this is undefined behavior that the 345 // optimizer will delete, so warn about it. People sometimes try to use this 346 // to get a deterministic trap and are surprised by clang's behavior. This 347 // only handles the pattern "*null", which is a very syntactic check. 348 if (UnaryOperator *UO = dyn_cast<UnaryOperator>(E->IgnoreParenCasts())) 349 if (UO->getOpcode() == UO_Deref && 350 UO->getSubExpr()->IgnoreParenCasts()-> 351 isNullPointerConstant(S.Context, Expr::NPC_ValueDependentIsNotNull) && 352 !UO->getType().isVolatileQualified()) { 353 S.DiagRuntimeBehavior(UO->getOperatorLoc(), UO, 354 S.PDiag(diag::warn_indirection_through_null) 355 << UO->getSubExpr()->getSourceRange()); 356 S.DiagRuntimeBehavior(UO->getOperatorLoc(), UO, 357 S.PDiag(diag::note_indirection_through_null)); 358 } 359} 360 361ExprResult Sema::DefaultLvalueConversion(Expr *E) { 362 // Handle any placeholder expressions which made it here. 363 if (E->getType()->isPlaceholderType()) { 364 ExprResult result = CheckPlaceholderExpr(E); 365 if (result.isInvalid()) return ExprError(); 366 E = result.take(); 367 } 368 369 // C++ [conv.lval]p1: 370 // A glvalue of a non-function, non-array type T can be 371 // converted to a prvalue. 372 if (!E->isGLValue()) return Owned(E); 373 374 QualType T = E->getType(); 375 assert(!T.isNull() && "r-value conversion on typeless expression?"); 376 377 // We can't do lvalue-to-rvalue on atomics yet. 378 if (T->isAtomicType()) 379 return Owned(E); 380 381 // We don't want to throw lvalue-to-rvalue casts on top of 382 // expressions of certain types in C++. 383 if (getLangOpts().CPlusPlus && 384 (E->getType() == Context.OverloadTy || 385 T->isDependentType() || 386 T->isRecordType())) 387 return Owned(E); 388 389 // The C standard is actually really unclear on this point, and 390 // DR106 tells us what the result should be but not why. It's 391 // generally best to say that void types just doesn't undergo 392 // lvalue-to-rvalue at all. Note that expressions of unqualified 393 // 'void' type are never l-values, but qualified void can be. 394 if (T->isVoidType()) 395 return Owned(E); 396 397 CheckForNullPointerDereference(*this, E); 398 399 // C++ [conv.lval]p1: 400 // [...] If T is a non-class type, the type of the prvalue is the 401 // cv-unqualified version of T. Otherwise, the type of the 402 // rvalue is T. 403 // 404 // C99 6.3.2.1p2: 405 // If the lvalue has qualified type, the value has the unqualified 406 // version of the type of the lvalue; otherwise, the value has the 407 // type of the lvalue. 408 if (T.hasQualifiers()) 409 T = T.getUnqualifiedType(); 410 411 UpdateMarkingForLValueToRValue(E); 412 413 ExprResult Res = Owned(ImplicitCastExpr::Create(Context, T, CK_LValueToRValue, 414 E, 0, VK_RValue)); 415 416 return Res; 417} 418 419ExprResult Sema::DefaultFunctionArrayLvalueConversion(Expr *E) { 420 ExprResult Res = DefaultFunctionArrayConversion(E); 421 if (Res.isInvalid()) 422 return ExprError(); 423 Res = DefaultLvalueConversion(Res.take()); 424 if (Res.isInvalid()) 425 return ExprError(); 426 return move(Res); 427} 428 429 430/// UsualUnaryConversions - Performs various conversions that are common to most 431/// operators (C99 6.3). The conversions of array and function types are 432/// sometimes suppressed. For example, the array->pointer conversion doesn't 433/// apply if the array is an argument to the sizeof or address (&) operators. 434/// In these instances, this routine should *not* be called. 435ExprResult Sema::UsualUnaryConversions(Expr *E) { 436 // First, convert to an r-value. 437 ExprResult Res = DefaultFunctionArrayLvalueConversion(E); 438 if (Res.isInvalid()) 439 return Owned(E); 440 E = Res.take(); 441 442 QualType Ty = E->getType(); 443 assert(!Ty.isNull() && "UsualUnaryConversions - missing type"); 444 445 // Half FP is a bit different: it's a storage-only type, meaning that any 446 // "use" of it should be promoted to float. 447 if (Ty->isHalfType()) 448 return ImpCastExprToType(Res.take(), Context.FloatTy, CK_FloatingCast); 449 450 // Try to perform integral promotions if the object has a theoretically 451 // promotable type. 452 if (Ty->isIntegralOrUnscopedEnumerationType()) { 453 // C99 6.3.1.1p2: 454 // 455 // The following may be used in an expression wherever an int or 456 // unsigned int may be used: 457 // - an object or expression with an integer type whose integer 458 // conversion rank is less than or equal to the rank of int 459 // and unsigned int. 460 // - A bit-field of type _Bool, int, signed int, or unsigned int. 461 // 462 // If an int can represent all values of the original type, the 463 // value is converted to an int; otherwise, it is converted to an 464 // unsigned int. These are called the integer promotions. All 465 // other types are unchanged by the integer promotions. 466 467 QualType PTy = Context.isPromotableBitField(E); 468 if (!PTy.isNull()) { 469 E = ImpCastExprToType(E, PTy, CK_IntegralCast).take(); 470 return Owned(E); 471 } 472 if (Ty->isPromotableIntegerType()) { 473 QualType PT = Context.getPromotedIntegerType(Ty); 474 E = ImpCastExprToType(E, PT, CK_IntegralCast).take(); 475 return Owned(E); 476 } 477 } 478 return Owned(E); 479} 480 481/// DefaultArgumentPromotion (C99 6.5.2.2p6). Used for function calls that 482/// do not have a prototype. Arguments that have type float are promoted to 483/// double. All other argument types are converted by UsualUnaryConversions(). 484ExprResult Sema::DefaultArgumentPromotion(Expr *E) { 485 QualType Ty = E->getType(); 486 assert(!Ty.isNull() && "DefaultArgumentPromotion - missing type"); 487 488 ExprResult Res = UsualUnaryConversions(E); 489 if (Res.isInvalid()) 490 return Owned(E); 491 E = Res.take(); 492 493 // If this is a 'float' (CVR qualified or typedef) promote to double. 494 if (Ty->isSpecificBuiltinType(BuiltinType::Float)) 495 E = ImpCastExprToType(E, Context.DoubleTy, CK_FloatingCast).take(); 496 497 // C++ performs lvalue-to-rvalue conversion as a default argument 498 // promotion, even on class types, but note: 499 // C++11 [conv.lval]p2: 500 // When an lvalue-to-rvalue conversion occurs in an unevaluated 501 // operand or a subexpression thereof the value contained in the 502 // referenced object is not accessed. Otherwise, if the glvalue 503 // has a class type, the conversion copy-initializes a temporary 504 // of type T from the glvalue and the result of the conversion 505 // is a prvalue for the temporary. 506 // FIXME: add some way to gate this entire thing for correctness in 507 // potentially potentially evaluated contexts. 508 if (getLangOpts().CPlusPlus && E->isGLValue() && 509 ExprEvalContexts.back().Context != Unevaluated) { 510 ExprResult Temp = PerformCopyInitialization( 511 InitializedEntity::InitializeTemporary(E->getType()), 512 E->getExprLoc(), 513 Owned(E)); 514 if (Temp.isInvalid()) 515 return ExprError(); 516 E = Temp.get(); 517 } 518 519 return Owned(E); 520} 521 522/// DefaultVariadicArgumentPromotion - Like DefaultArgumentPromotion, but 523/// will warn if the resulting type is not a POD type, and rejects ObjC 524/// interfaces passed by value. 525ExprResult Sema::DefaultVariadicArgumentPromotion(Expr *E, VariadicCallType CT, 526 FunctionDecl *FDecl) { 527 if (const BuiltinType *PlaceholderTy = E->getType()->getAsPlaceholderType()) { 528 // Strip the unbridged-cast placeholder expression off, if applicable. 529 if (PlaceholderTy->getKind() == BuiltinType::ARCUnbridgedCast && 530 (CT == VariadicMethod || 531 (FDecl && FDecl->hasAttr<CFAuditedTransferAttr>()))) { 532 E = stripARCUnbridgedCast(E); 533 534 // Otherwise, do normal placeholder checking. 535 } else { 536 ExprResult ExprRes = CheckPlaceholderExpr(E); 537 if (ExprRes.isInvalid()) 538 return ExprError(); 539 E = ExprRes.take(); 540 } 541 } 542 543 ExprResult ExprRes = DefaultArgumentPromotion(E); 544 if (ExprRes.isInvalid()) 545 return ExprError(); 546 E = ExprRes.take(); 547 548 // Don't allow one to pass an Objective-C interface to a vararg. 549 if (E->getType()->isObjCObjectType() && 550 DiagRuntimeBehavior(E->getLocStart(), 0, 551 PDiag(diag::err_cannot_pass_objc_interface_to_vararg) 552 << E->getType() << CT)) 553 return ExprError(); 554 555 // Complain about passing non-POD types through varargs. However, don't 556 // perform this check for incomplete types, which we can get here when we're 557 // in an unevaluated context. 558 if (!E->getType()->isIncompleteType() && !E->getType().isPODType(Context)) { 559 // C++0x [expr.call]p7: 560 // Passing a potentially-evaluated argument of class type (Clause 9) 561 // having a non-trivial copy constructor, a non-trivial move constructor, 562 // or a non-trivial destructor, with no corresponding parameter, 563 // is conditionally-supported with implementation-defined semantics. 564 bool TrivialEnough = false; 565 if (getLangOpts().CPlusPlus0x && !E->getType()->isDependentType()) { 566 if (CXXRecordDecl *Record = E->getType()->getAsCXXRecordDecl()) { 567 if (Record->hasTrivialCopyConstructor() && 568 Record->hasTrivialMoveConstructor() && 569 Record->hasTrivialDestructor()) { 570 DiagRuntimeBehavior(E->getLocStart(), 0, 571 PDiag(diag::warn_cxx98_compat_pass_non_pod_arg_to_vararg) 572 << E->getType() << CT); 573 TrivialEnough = true; 574 } 575 } 576 } 577 578 if (!TrivialEnough && 579 getLangOpts().ObjCAutoRefCount && 580 E->getType()->isObjCLifetimeType()) 581 TrivialEnough = true; 582 583 if (TrivialEnough) { 584 // Nothing to diagnose. This is okay. 585 } else if (DiagRuntimeBehavior(E->getLocStart(), 0, 586 PDiag(diag::warn_cannot_pass_non_pod_arg_to_vararg) 587 << getLangOpts().CPlusPlus0x << E->getType() 588 << CT)) { 589 // Turn this into a trap. 590 CXXScopeSpec SS; 591 SourceLocation TemplateKWLoc; 592 UnqualifiedId Name; 593 Name.setIdentifier(PP.getIdentifierInfo("__builtin_trap"), 594 E->getLocStart()); 595 ExprResult TrapFn = ActOnIdExpression(TUScope, SS, TemplateKWLoc, Name, 596 true, false); 597 if (TrapFn.isInvalid()) 598 return ExprError(); 599 600 ExprResult Call = ActOnCallExpr(TUScope, TrapFn.get(), E->getLocStart(), 601 MultiExprArg(), E->getLocEnd()); 602 if (Call.isInvalid()) 603 return ExprError(); 604 605 ExprResult Comma = ActOnBinOp(TUScope, E->getLocStart(), tok::comma, 606 Call.get(), E); 607 if (Comma.isInvalid()) 608 return ExprError(); 609 E = Comma.get(); 610 } 611 } 612 // c++ rules are enforced elsewhere. 613 if (!getLangOpts().CPlusPlus && 614 RequireCompleteType(E->getExprLoc(), E->getType(), 615 diag::err_call_incomplete_argument)) 616 return ExprError(); 617 618 return Owned(E); 619} 620 621/// \brief Converts an integer to complex float type. Helper function of 622/// UsualArithmeticConversions() 623/// 624/// \return false if the integer expression is an integer type and is 625/// successfully converted to the complex type. 626static bool handleIntegerToComplexFloatConversion(Sema &S, ExprResult &IntExpr, 627 ExprResult &ComplexExpr, 628 QualType IntTy, 629 QualType ComplexTy, 630 bool SkipCast) { 631 if (IntTy->isComplexType() || IntTy->isRealFloatingType()) return true; 632 if (SkipCast) return false; 633 if (IntTy->isIntegerType()) { 634 QualType fpTy = cast<ComplexType>(ComplexTy)->getElementType(); 635 IntExpr = S.ImpCastExprToType(IntExpr.take(), fpTy, CK_IntegralToFloating); 636 IntExpr = S.ImpCastExprToType(IntExpr.take(), ComplexTy, 637 CK_FloatingRealToComplex); 638 } else { 639 assert(IntTy->isComplexIntegerType()); 640 IntExpr = S.ImpCastExprToType(IntExpr.take(), ComplexTy, 641 CK_IntegralComplexToFloatingComplex); 642 } 643 return false; 644} 645 646/// \brief Takes two complex float types and converts them to the same type. 647/// Helper function of UsualArithmeticConversions() 648static QualType 649handleComplexFloatToComplexFloatConverstion(Sema &S, ExprResult &LHS, 650 ExprResult &RHS, QualType LHSType, 651 QualType RHSType, 652 bool IsCompAssign) { 653 int order = S.Context.getFloatingTypeOrder(LHSType, RHSType); 654 655 if (order < 0) { 656 // _Complex float -> _Complex double 657 if (!IsCompAssign) 658 LHS = S.ImpCastExprToType(LHS.take(), RHSType, CK_FloatingComplexCast); 659 return RHSType; 660 } 661 if (order > 0) 662 // _Complex float -> _Complex double 663 RHS = S.ImpCastExprToType(RHS.take(), LHSType, CK_FloatingComplexCast); 664 return LHSType; 665} 666 667/// \brief Converts otherExpr to complex float and promotes complexExpr if 668/// necessary. Helper function of UsualArithmeticConversions() 669static QualType handleOtherComplexFloatConversion(Sema &S, 670 ExprResult &ComplexExpr, 671 ExprResult &OtherExpr, 672 QualType ComplexTy, 673 QualType OtherTy, 674 bool ConvertComplexExpr, 675 bool ConvertOtherExpr) { 676 int order = S.Context.getFloatingTypeOrder(ComplexTy, OtherTy); 677 678 // If just the complexExpr is complex, the otherExpr needs to be converted, 679 // and the complexExpr might need to be promoted. 680 if (order > 0) { // complexExpr is wider 681 // float -> _Complex double 682 if (ConvertOtherExpr) { 683 QualType fp = cast<ComplexType>(ComplexTy)->getElementType(); 684 OtherExpr = S.ImpCastExprToType(OtherExpr.take(), fp, CK_FloatingCast); 685 OtherExpr = S.ImpCastExprToType(OtherExpr.take(), ComplexTy, 686 CK_FloatingRealToComplex); 687 } 688 return ComplexTy; 689 } 690 691 // otherTy is at least as wide. Find its corresponding complex type. 692 QualType result = (order == 0 ? ComplexTy : 693 S.Context.getComplexType(OtherTy)); 694 695 // double -> _Complex double 696 if (ConvertOtherExpr) 697 OtherExpr = S.ImpCastExprToType(OtherExpr.take(), result, 698 CK_FloatingRealToComplex); 699 700 // _Complex float -> _Complex double 701 if (ConvertComplexExpr && order < 0) 702 ComplexExpr = S.ImpCastExprToType(ComplexExpr.take(), result, 703 CK_FloatingComplexCast); 704 705 return result; 706} 707 708/// \brief Handle arithmetic conversion with complex types. Helper function of 709/// UsualArithmeticConversions() 710static QualType handleComplexFloatConversion(Sema &S, ExprResult &LHS, 711 ExprResult &RHS, QualType LHSType, 712 QualType RHSType, 713 bool IsCompAssign) { 714 // if we have an integer operand, the result is the complex type. 715 if (!handleIntegerToComplexFloatConversion(S, RHS, LHS, RHSType, LHSType, 716 /*skipCast*/false)) 717 return LHSType; 718 if (!handleIntegerToComplexFloatConversion(S, LHS, RHS, LHSType, RHSType, 719 /*skipCast*/IsCompAssign)) 720 return RHSType; 721 722 // This handles complex/complex, complex/float, or float/complex. 723 // When both operands are complex, the shorter operand is converted to the 724 // type of the longer, and that is the type of the result. This corresponds 725 // to what is done when combining two real floating-point operands. 726 // The fun begins when size promotion occur across type domains. 727 // From H&S 6.3.4: When one operand is complex and the other is a real 728 // floating-point type, the less precise type is converted, within it's 729 // real or complex domain, to the precision of the other type. For example, 730 // when combining a "long double" with a "double _Complex", the 731 // "double _Complex" is promoted to "long double _Complex". 732 733 bool LHSComplexFloat = LHSType->isComplexType(); 734 bool RHSComplexFloat = RHSType->isComplexType(); 735 736 // If both are complex, just cast to the more precise type. 737 if (LHSComplexFloat && RHSComplexFloat) 738 return handleComplexFloatToComplexFloatConverstion(S, LHS, RHS, 739 LHSType, RHSType, 740 IsCompAssign); 741 742 // If only one operand is complex, promote it if necessary and convert the 743 // other operand to complex. 744 if (LHSComplexFloat) 745 return handleOtherComplexFloatConversion( 746 S, LHS, RHS, LHSType, RHSType, /*convertComplexExpr*/!IsCompAssign, 747 /*convertOtherExpr*/ true); 748 749 assert(RHSComplexFloat); 750 return handleOtherComplexFloatConversion( 751 S, RHS, LHS, RHSType, LHSType, /*convertComplexExpr*/true, 752 /*convertOtherExpr*/ !IsCompAssign); 753} 754 755/// \brief Hande arithmetic conversion from integer to float. Helper function 756/// of UsualArithmeticConversions() 757static QualType handleIntToFloatConversion(Sema &S, ExprResult &FloatExpr, 758 ExprResult &IntExpr, 759 QualType FloatTy, QualType IntTy, 760 bool ConvertFloat, bool ConvertInt) { 761 if (IntTy->isIntegerType()) { 762 if (ConvertInt) 763 // Convert intExpr to the lhs floating point type. 764 IntExpr = S.ImpCastExprToType(IntExpr.take(), FloatTy, 765 CK_IntegralToFloating); 766 return FloatTy; 767 } 768 769 // Convert both sides to the appropriate complex float. 770 assert(IntTy->isComplexIntegerType()); 771 QualType result = S.Context.getComplexType(FloatTy); 772 773 // _Complex int -> _Complex float 774 if (ConvertInt) 775 IntExpr = S.ImpCastExprToType(IntExpr.take(), result, 776 CK_IntegralComplexToFloatingComplex); 777 778 // float -> _Complex float 779 if (ConvertFloat) 780 FloatExpr = S.ImpCastExprToType(FloatExpr.take(), result, 781 CK_FloatingRealToComplex); 782 783 return result; 784} 785 786/// \brief Handle arithmethic conversion with floating point types. Helper 787/// function of UsualArithmeticConversions() 788static QualType handleFloatConversion(Sema &S, ExprResult &LHS, 789 ExprResult &RHS, QualType LHSType, 790 QualType RHSType, bool IsCompAssign) { 791 bool LHSFloat = LHSType->isRealFloatingType(); 792 bool RHSFloat = RHSType->isRealFloatingType(); 793 794 // If we have two real floating types, convert the smaller operand 795 // to the bigger result. 796 if (LHSFloat && RHSFloat) { 797 int order = S.Context.getFloatingTypeOrder(LHSType, RHSType); 798 if (order > 0) { 799 RHS = S.ImpCastExprToType(RHS.take(), LHSType, CK_FloatingCast); 800 return LHSType; 801 } 802 803 assert(order < 0 && "illegal float comparison"); 804 if (!IsCompAssign) 805 LHS = S.ImpCastExprToType(LHS.take(), RHSType, CK_FloatingCast); 806 return RHSType; 807 } 808 809 if (LHSFloat) 810 return handleIntToFloatConversion(S, LHS, RHS, LHSType, RHSType, 811 /*convertFloat=*/!IsCompAssign, 812 /*convertInt=*/ true); 813 assert(RHSFloat); 814 return handleIntToFloatConversion(S, RHS, LHS, RHSType, LHSType, 815 /*convertInt=*/ true, 816 /*convertFloat=*/!IsCompAssign); 817} 818 819/// \brief Handle conversions with GCC complex int extension. Helper function 820/// of UsualArithmeticConversions() 821// FIXME: if the operands are (int, _Complex long), we currently 822// don't promote the complex. Also, signedness? 823static QualType handleComplexIntConversion(Sema &S, ExprResult &LHS, 824 ExprResult &RHS, QualType LHSType, 825 QualType RHSType, 826 bool IsCompAssign) { 827 const ComplexType *LHSComplexInt = LHSType->getAsComplexIntegerType(); 828 const ComplexType *RHSComplexInt = RHSType->getAsComplexIntegerType(); 829 830 if (LHSComplexInt && RHSComplexInt) { 831 int order = S.Context.getIntegerTypeOrder(LHSComplexInt->getElementType(), 832 RHSComplexInt->getElementType()); 833 assert(order && "inequal types with equal element ordering"); 834 if (order > 0) { 835 // _Complex int -> _Complex long 836 RHS = S.ImpCastExprToType(RHS.take(), LHSType, CK_IntegralComplexCast); 837 return LHSType; 838 } 839 840 if (!IsCompAssign) 841 LHS = S.ImpCastExprToType(LHS.take(), RHSType, CK_IntegralComplexCast); 842 return RHSType; 843 } 844 845 if (LHSComplexInt) { 846 // int -> _Complex int 847 // FIXME: This needs to take integer ranks into account 848 RHS = S.ImpCastExprToType(RHS.take(), LHSComplexInt->getElementType(), 849 CK_IntegralCast); 850 RHS = S.ImpCastExprToType(RHS.take(), LHSType, CK_IntegralRealToComplex); 851 return LHSType; 852 } 853 854 assert(RHSComplexInt); 855 // int -> _Complex int 856 // FIXME: This needs to take integer ranks into account 857 if (!IsCompAssign) { 858 LHS = S.ImpCastExprToType(LHS.take(), RHSComplexInt->getElementType(), 859 CK_IntegralCast); 860 LHS = S.ImpCastExprToType(LHS.take(), RHSType, CK_IntegralRealToComplex); 861 } 862 return RHSType; 863} 864 865/// \brief Handle integer arithmetic conversions. Helper function of 866/// UsualArithmeticConversions() 867static QualType handleIntegerConversion(Sema &S, ExprResult &LHS, 868 ExprResult &RHS, QualType LHSType, 869 QualType RHSType, bool IsCompAssign) { 870 // The rules for this case are in C99 6.3.1.8 871 int order = S.Context.getIntegerTypeOrder(LHSType, RHSType); 872 bool LHSSigned = LHSType->hasSignedIntegerRepresentation(); 873 bool RHSSigned = RHSType->hasSignedIntegerRepresentation(); 874 if (LHSSigned == RHSSigned) { 875 // Same signedness; use the higher-ranked type 876 if (order >= 0) { 877 RHS = S.ImpCastExprToType(RHS.take(), LHSType, CK_IntegralCast); 878 return LHSType; 879 } else if (!IsCompAssign) 880 LHS = S.ImpCastExprToType(LHS.take(), RHSType, CK_IntegralCast); 881 return RHSType; 882 } else if (order != (LHSSigned ? 1 : -1)) { 883 // The unsigned type has greater than or equal rank to the 884 // signed type, so use the unsigned type 885 if (RHSSigned) { 886 RHS = S.ImpCastExprToType(RHS.take(), LHSType, CK_IntegralCast); 887 return LHSType; 888 } else if (!IsCompAssign) 889 LHS = S.ImpCastExprToType(LHS.take(), RHSType, CK_IntegralCast); 890 return RHSType; 891 } else if (S.Context.getIntWidth(LHSType) != S.Context.getIntWidth(RHSType)) { 892 // The two types are different widths; if we are here, that 893 // means the signed type is larger than the unsigned type, so 894 // use the signed type. 895 if (LHSSigned) { 896 RHS = S.ImpCastExprToType(RHS.take(), LHSType, CK_IntegralCast); 897 return LHSType; 898 } else if (!IsCompAssign) 899 LHS = S.ImpCastExprToType(LHS.take(), RHSType, CK_IntegralCast); 900 return RHSType; 901 } else { 902 // The signed type is higher-ranked than the unsigned type, 903 // but isn't actually any bigger (like unsigned int and long 904 // on most 32-bit systems). Use the unsigned type corresponding 905 // to the signed type. 906 QualType result = 907 S.Context.getCorrespondingUnsignedType(LHSSigned ? LHSType : RHSType); 908 RHS = S.ImpCastExprToType(RHS.take(), result, CK_IntegralCast); 909 if (!IsCompAssign) 910 LHS = S.ImpCastExprToType(LHS.take(), result, CK_IntegralCast); 911 return result; 912 } 913} 914 915/// UsualArithmeticConversions - Performs various conversions that are common to 916/// binary operators (C99 6.3.1.8). If both operands aren't arithmetic, this 917/// routine returns the first non-arithmetic type found. The client is 918/// responsible for emitting appropriate error diagnostics. 919/// FIXME: verify the conversion rules for "complex int" are consistent with 920/// GCC. 921QualType Sema::UsualArithmeticConversions(ExprResult &LHS, ExprResult &RHS, 922 bool IsCompAssign) { 923 if (!IsCompAssign) { 924 LHS = UsualUnaryConversions(LHS.take()); 925 if (LHS.isInvalid()) 926 return QualType(); 927 } 928 929 RHS = UsualUnaryConversions(RHS.take()); 930 if (RHS.isInvalid()) 931 return QualType(); 932 933 // For conversion purposes, we ignore any qualifiers. 934 // For example, "const float" and "float" are equivalent. 935 QualType LHSType = 936 Context.getCanonicalType(LHS.get()->getType()).getUnqualifiedType(); 937 QualType RHSType = 938 Context.getCanonicalType(RHS.get()->getType()).getUnqualifiedType(); 939 940 // If both types are identical, no conversion is needed. 941 if (LHSType == RHSType) 942 return LHSType; 943 944 // If either side is a non-arithmetic type (e.g. a pointer), we are done. 945 // The caller can deal with this (e.g. pointer + int). 946 if (!LHSType->isArithmeticType() || !RHSType->isArithmeticType()) 947 return LHSType; 948 949 // Apply unary and bitfield promotions to the LHS's type. 950 QualType LHSUnpromotedType = LHSType; 951 if (LHSType->isPromotableIntegerType()) 952 LHSType = Context.getPromotedIntegerType(LHSType); 953 QualType LHSBitfieldPromoteTy = Context.isPromotableBitField(LHS.get()); 954 if (!LHSBitfieldPromoteTy.isNull()) 955 LHSType = LHSBitfieldPromoteTy; 956 if (LHSType != LHSUnpromotedType && !IsCompAssign) 957 LHS = ImpCastExprToType(LHS.take(), LHSType, CK_IntegralCast); 958 959 // If both types are identical, no conversion is needed. 960 if (LHSType == RHSType) 961 return LHSType; 962 963 // At this point, we have two different arithmetic types. 964 965 // Handle complex types first (C99 6.3.1.8p1). 966 if (LHSType->isComplexType() || RHSType->isComplexType()) 967 return handleComplexFloatConversion(*this, LHS, RHS, LHSType, RHSType, 968 IsCompAssign); 969 970 // Now handle "real" floating types (i.e. float, double, long double). 971 if (LHSType->isRealFloatingType() || RHSType->isRealFloatingType()) 972 return handleFloatConversion(*this, LHS, RHS, LHSType, RHSType, 973 IsCompAssign); 974 975 // Handle GCC complex int extension. 976 if (LHSType->isComplexIntegerType() || RHSType->isComplexIntegerType()) 977 return handleComplexIntConversion(*this, LHS, RHS, LHSType, RHSType, 978 IsCompAssign); 979 980 // Finally, we have two differing integer types. 981 return handleIntegerConversion(*this, LHS, RHS, LHSType, RHSType, 982 IsCompAssign); 983} 984 985//===----------------------------------------------------------------------===// 986// Semantic Analysis for various Expression Types 987//===----------------------------------------------------------------------===// 988 989 990ExprResult 991Sema::ActOnGenericSelectionExpr(SourceLocation KeyLoc, 992 SourceLocation DefaultLoc, 993 SourceLocation RParenLoc, 994 Expr *ControllingExpr, 995 MultiTypeArg ArgTypes, 996 MultiExprArg ArgExprs) { 997 unsigned NumAssocs = ArgTypes.size(); 998 assert(NumAssocs == ArgExprs.size()); 999 1000 ParsedType *ParsedTypes = ArgTypes.release(); 1001 Expr **Exprs = ArgExprs.release(); 1002 1003 TypeSourceInfo **Types = new TypeSourceInfo*[NumAssocs]; 1004 for (unsigned i = 0; i < NumAssocs; ++i) { 1005 if (ParsedTypes[i]) 1006 (void) GetTypeFromParser(ParsedTypes[i], &Types[i]); 1007 else 1008 Types[i] = 0; 1009 } 1010 1011 ExprResult ER = CreateGenericSelectionExpr(KeyLoc, DefaultLoc, RParenLoc, 1012 ControllingExpr, Types, Exprs, 1013 NumAssocs); 1014 delete [] Types; 1015 return ER; 1016} 1017 1018ExprResult 1019Sema::CreateGenericSelectionExpr(SourceLocation KeyLoc, 1020 SourceLocation DefaultLoc, 1021 SourceLocation RParenLoc, 1022 Expr *ControllingExpr, 1023 TypeSourceInfo **Types, 1024 Expr **Exprs, 1025 unsigned NumAssocs) { 1026 bool TypeErrorFound = false, 1027 IsResultDependent = ControllingExpr->isTypeDependent(), 1028 ContainsUnexpandedParameterPack 1029 = ControllingExpr->containsUnexpandedParameterPack(); 1030 1031 for (unsigned i = 0; i < NumAssocs; ++i) { 1032 if (Exprs[i]->containsUnexpandedParameterPack()) 1033 ContainsUnexpandedParameterPack = true; 1034 1035 if (Types[i]) { 1036 if (Types[i]->getType()->containsUnexpandedParameterPack()) 1037 ContainsUnexpandedParameterPack = true; 1038 1039 if (Types[i]->getType()->isDependentType()) { 1040 IsResultDependent = true; 1041 } else { 1042 // C11 6.5.1.1p2 "The type name in a generic association shall specify a 1043 // complete object type other than a variably modified type." 1044 unsigned D = 0; 1045 if (Types[i]->getType()->isIncompleteType()) 1046 D = diag::err_assoc_type_incomplete; 1047 else if (!Types[i]->getType()->isObjectType()) 1048 D = diag::err_assoc_type_nonobject; 1049 else if (Types[i]->getType()->isVariablyModifiedType()) 1050 D = diag::err_assoc_type_variably_modified; 1051 1052 if (D != 0) { 1053 Diag(Types[i]->getTypeLoc().getBeginLoc(), D) 1054 << Types[i]->getTypeLoc().getSourceRange() 1055 << Types[i]->getType(); 1056 TypeErrorFound = true; 1057 } 1058 1059 // C11 6.5.1.1p2 "No two generic associations in the same generic 1060 // selection shall specify compatible types." 1061 for (unsigned j = i+1; j < NumAssocs; ++j) 1062 if (Types[j] && !Types[j]->getType()->isDependentType() && 1063 Context.typesAreCompatible(Types[i]->getType(), 1064 Types[j]->getType())) { 1065 Diag(Types[j]->getTypeLoc().getBeginLoc(), 1066 diag::err_assoc_compatible_types) 1067 << Types[j]->getTypeLoc().getSourceRange() 1068 << Types[j]->getType() 1069 << Types[i]->getType(); 1070 Diag(Types[i]->getTypeLoc().getBeginLoc(), 1071 diag::note_compat_assoc) 1072 << Types[i]->getTypeLoc().getSourceRange() 1073 << Types[i]->getType(); 1074 TypeErrorFound = true; 1075 } 1076 } 1077 } 1078 } 1079 if (TypeErrorFound) 1080 return ExprError(); 1081 1082 // If we determined that the generic selection is result-dependent, don't 1083 // try to compute the result expression. 1084 if (IsResultDependent) 1085 return Owned(new (Context) GenericSelectionExpr( 1086 Context, KeyLoc, ControllingExpr, 1087 Types, Exprs, NumAssocs, DefaultLoc, 1088 RParenLoc, ContainsUnexpandedParameterPack)); 1089 1090 SmallVector<unsigned, 1> CompatIndices; 1091 unsigned DefaultIndex = -1U; 1092 for (unsigned i = 0; i < NumAssocs; ++i) { 1093 if (!Types[i]) 1094 DefaultIndex = i; 1095 else if (Context.typesAreCompatible(ControllingExpr->getType(), 1096 Types[i]->getType())) 1097 CompatIndices.push_back(i); 1098 } 1099 1100 // C11 6.5.1.1p2 "The controlling expression of a generic selection shall have 1101 // type compatible with at most one of the types named in its generic 1102 // association list." 1103 if (CompatIndices.size() > 1) { 1104 // We strip parens here because the controlling expression is typically 1105 // parenthesized in macro definitions. 1106 ControllingExpr = ControllingExpr->IgnoreParens(); 1107 Diag(ControllingExpr->getLocStart(), diag::err_generic_sel_multi_match) 1108 << ControllingExpr->getSourceRange() << ControllingExpr->getType() 1109 << (unsigned) CompatIndices.size(); 1110 for (SmallVector<unsigned, 1>::iterator I = CompatIndices.begin(), 1111 E = CompatIndices.end(); I != E; ++I) { 1112 Diag(Types[*I]->getTypeLoc().getBeginLoc(), 1113 diag::note_compat_assoc) 1114 << Types[*I]->getTypeLoc().getSourceRange() 1115 << Types[*I]->getType(); 1116 } 1117 return ExprError(); 1118 } 1119 1120 // C11 6.5.1.1p2 "If a generic selection has no default generic association, 1121 // its controlling expression shall have type compatible with exactly one of 1122 // the types named in its generic association list." 1123 if (DefaultIndex == -1U && CompatIndices.size() == 0) { 1124 // We strip parens here because the controlling expression is typically 1125 // parenthesized in macro definitions. 1126 ControllingExpr = ControllingExpr->IgnoreParens(); 1127 Diag(ControllingExpr->getLocStart(), diag::err_generic_sel_no_match) 1128 << ControllingExpr->getSourceRange() << ControllingExpr->getType(); 1129 return ExprError(); 1130 } 1131 1132 // C11 6.5.1.1p3 "If a generic selection has a generic association with a 1133 // type name that is compatible with the type of the controlling expression, 1134 // then the result expression of the generic selection is the expression 1135 // in that generic association. Otherwise, the result expression of the 1136 // generic selection is the expression in the default generic association." 1137 unsigned ResultIndex = 1138 CompatIndices.size() ? CompatIndices[0] : DefaultIndex; 1139 1140 return Owned(new (Context) GenericSelectionExpr( 1141 Context, KeyLoc, ControllingExpr, 1142 Types, Exprs, NumAssocs, DefaultLoc, 1143 RParenLoc, ContainsUnexpandedParameterPack, 1144 ResultIndex)); 1145} 1146 1147/// getUDSuffixLoc - Create a SourceLocation for a ud-suffix, given the 1148/// location of the token and the offset of the ud-suffix within it. 1149static SourceLocation getUDSuffixLoc(Sema &S, SourceLocation TokLoc, 1150 unsigned Offset) { 1151 return Lexer::AdvanceToTokenCharacter(TokLoc, Offset, S.getSourceManager(), 1152 S.getLangOpts()); 1153} 1154 1155/// BuildCookedLiteralOperatorCall - A user-defined literal was found. Look up 1156/// the corresponding cooked (non-raw) literal operator, and build a call to it. 1157static ExprResult BuildCookedLiteralOperatorCall(Sema &S, Scope *Scope, 1158 IdentifierInfo *UDSuffix, 1159 SourceLocation UDSuffixLoc, 1160 ArrayRef<Expr*> Args, 1161 SourceLocation LitEndLoc) { 1162 assert(Args.size() <= 2 && "too many arguments for literal operator"); 1163 1164 QualType ArgTy[2]; 1165 for (unsigned ArgIdx = 0; ArgIdx != Args.size(); ++ArgIdx) { 1166 ArgTy[ArgIdx] = Args[ArgIdx]->getType(); 1167 if (ArgTy[ArgIdx]->isArrayType()) 1168 ArgTy[ArgIdx] = S.Context.getArrayDecayedType(ArgTy[ArgIdx]); 1169 } 1170 1171 DeclarationName OpName = 1172 S.Context.DeclarationNames.getCXXLiteralOperatorName(UDSuffix); 1173 DeclarationNameInfo OpNameInfo(OpName, UDSuffixLoc); 1174 OpNameInfo.setCXXLiteralOperatorNameLoc(UDSuffixLoc); 1175 1176 LookupResult R(S, OpName, UDSuffixLoc, Sema::LookupOrdinaryName); 1177 if (S.LookupLiteralOperator(Scope, R, llvm::makeArrayRef(ArgTy, Args.size()), 1178 /*AllowRawAndTemplate*/false) == Sema::LOLR_Error) 1179 return ExprError(); 1180 1181 return S.BuildLiteralOperatorCall(R, OpNameInfo, Args, LitEndLoc); 1182} 1183 1184/// ActOnStringLiteral - The specified tokens were lexed as pasted string 1185/// fragments (e.g. "foo" "bar" L"baz"). The result string has to handle string 1186/// concatenation ([C99 5.1.1.2, translation phase #6]), so it may come from 1187/// multiple tokens. However, the common case is that StringToks points to one 1188/// string. 1189/// 1190ExprResult 1191Sema::ActOnStringLiteral(const Token *StringToks, unsigned NumStringToks, 1192 Scope *UDLScope) { 1193 assert(NumStringToks && "Must have at least one string!"); 1194 1195 StringLiteralParser Literal(StringToks, NumStringToks, PP); 1196 if (Literal.hadError) 1197 return ExprError(); 1198 1199 SmallVector<SourceLocation, 4> StringTokLocs; 1200 for (unsigned i = 0; i != NumStringToks; ++i) 1201 StringTokLocs.push_back(StringToks[i].getLocation()); 1202 1203 QualType StrTy = Context.CharTy; 1204 if (Literal.isWide()) 1205 StrTy = Context.getWCharType(); 1206 else if (Literal.isUTF16()) 1207 StrTy = Context.Char16Ty; 1208 else if (Literal.isUTF32()) 1209 StrTy = Context.Char32Ty; 1210 else if (Literal.isPascal()) 1211 StrTy = Context.UnsignedCharTy; 1212 1213 StringLiteral::StringKind Kind = StringLiteral::Ascii; 1214 if (Literal.isWide()) 1215 Kind = StringLiteral::Wide; 1216 else if (Literal.isUTF8()) 1217 Kind = StringLiteral::UTF8; 1218 else if (Literal.isUTF16()) 1219 Kind = StringLiteral::UTF16; 1220 else if (Literal.isUTF32()) 1221 Kind = StringLiteral::UTF32; 1222 1223 // A C++ string literal has a const-qualified element type (C++ 2.13.4p1). 1224 if (getLangOpts().CPlusPlus || getLangOpts().ConstStrings) 1225 StrTy.addConst(); 1226 1227 // Get an array type for the string, according to C99 6.4.5. This includes 1228 // the nul terminator character as well as the string length for pascal 1229 // strings. 1230 StrTy = Context.getConstantArrayType(StrTy, 1231 llvm::APInt(32, Literal.GetNumStringChars()+1), 1232 ArrayType::Normal, 0); 1233 1234 // Pass &StringTokLocs[0], StringTokLocs.size() to factory! 1235 StringLiteral *Lit = StringLiteral::Create(Context, Literal.GetString(), 1236 Kind, Literal.Pascal, StrTy, 1237 &StringTokLocs[0], 1238 StringTokLocs.size()); 1239 if (Literal.getUDSuffix().empty()) 1240 return Owned(Lit); 1241 1242 // We're building a user-defined literal. 1243 IdentifierInfo *UDSuffix = &Context.Idents.get(Literal.getUDSuffix()); 1244 SourceLocation UDSuffixLoc = 1245 getUDSuffixLoc(*this, StringTokLocs[Literal.getUDSuffixToken()], 1246 Literal.getUDSuffixOffset()); 1247 1248 // Make sure we're allowed user-defined literals here. 1249 if (!UDLScope) 1250 return ExprError(Diag(UDSuffixLoc, diag::err_invalid_string_udl)); 1251 1252 // C++11 [lex.ext]p5: The literal L is treated as a call of the form 1253 // operator "" X (str, len) 1254 QualType SizeType = Context.getSizeType(); 1255 llvm::APInt Len(Context.getIntWidth(SizeType), Literal.GetNumStringChars()); 1256 IntegerLiteral *LenArg = IntegerLiteral::Create(Context, Len, SizeType, 1257 StringTokLocs[0]); 1258 Expr *Args[] = { Lit, LenArg }; 1259 return BuildCookedLiteralOperatorCall(*this, UDLScope, UDSuffix, UDSuffixLoc, 1260 Args, StringTokLocs.back()); 1261} 1262 1263ExprResult 1264Sema::BuildDeclRefExpr(ValueDecl *D, QualType Ty, ExprValueKind VK, 1265 SourceLocation Loc, 1266 const CXXScopeSpec *SS) { 1267 DeclarationNameInfo NameInfo(D->getDeclName(), Loc); 1268 return BuildDeclRefExpr(D, Ty, VK, NameInfo, SS); 1269} 1270 1271/// BuildDeclRefExpr - Build an expression that references a 1272/// declaration that does not require a closure capture. 1273ExprResult 1274Sema::BuildDeclRefExpr(ValueDecl *D, QualType Ty, ExprValueKind VK, 1275 const DeclarationNameInfo &NameInfo, 1276 const CXXScopeSpec *SS) { 1277 if (getLangOpts().CUDA) 1278 if (const FunctionDecl *Caller = dyn_cast<FunctionDecl>(CurContext)) 1279 if (const FunctionDecl *Callee = dyn_cast<FunctionDecl>(D)) { 1280 CUDAFunctionTarget CallerTarget = IdentifyCUDATarget(Caller), 1281 CalleeTarget = IdentifyCUDATarget(Callee); 1282 if (CheckCUDATarget(CallerTarget, CalleeTarget)) { 1283 Diag(NameInfo.getLoc(), diag::err_ref_bad_target) 1284 << CalleeTarget << D->getIdentifier() << CallerTarget; 1285 Diag(D->getLocation(), diag::note_previous_decl) 1286 << D->getIdentifier(); 1287 return ExprError(); 1288 } 1289 } 1290 1291 bool refersToEnclosingScope = 1292 (CurContext != D->getDeclContext() && 1293 D->getDeclContext()->isFunctionOrMethod()); 1294 1295 DeclRefExpr *E = DeclRefExpr::Create(Context, 1296 SS ? SS->getWithLocInContext(Context) 1297 : NestedNameSpecifierLoc(), 1298 SourceLocation(), 1299 D, refersToEnclosingScope, 1300 NameInfo, Ty, VK); 1301 1302 MarkDeclRefReferenced(E); 1303 1304 // Just in case we're building an illegal pointer-to-member. 1305 FieldDecl *FD = dyn_cast<FieldDecl>(D); 1306 if (FD && FD->isBitField()) 1307 E->setObjectKind(OK_BitField); 1308 1309 return Owned(E); 1310} 1311 1312/// Decomposes the given name into a DeclarationNameInfo, its location, and 1313/// possibly a list of template arguments. 1314/// 1315/// If this produces template arguments, it is permitted to call 1316/// DecomposeTemplateName. 1317/// 1318/// This actually loses a lot of source location information for 1319/// non-standard name kinds; we should consider preserving that in 1320/// some way. 1321void 1322Sema::DecomposeUnqualifiedId(const UnqualifiedId &Id, 1323 TemplateArgumentListInfo &Buffer, 1324 DeclarationNameInfo &NameInfo, 1325 const TemplateArgumentListInfo *&TemplateArgs) { 1326 if (Id.getKind() == UnqualifiedId::IK_TemplateId) { 1327 Buffer.setLAngleLoc(Id.TemplateId->LAngleLoc); 1328 Buffer.setRAngleLoc(Id.TemplateId->RAngleLoc); 1329 1330 ASTTemplateArgsPtr TemplateArgsPtr(*this, 1331 Id.TemplateId->getTemplateArgs(), 1332 Id.TemplateId->NumArgs); 1333 translateTemplateArguments(TemplateArgsPtr, Buffer); 1334 TemplateArgsPtr.release(); 1335 1336 TemplateName TName = Id.TemplateId->Template.get(); 1337 SourceLocation TNameLoc = Id.TemplateId->TemplateNameLoc; 1338 NameInfo = Context.getNameForTemplate(TName, TNameLoc); 1339 TemplateArgs = &Buffer; 1340 } else { 1341 NameInfo = GetNameFromUnqualifiedId(Id); 1342 TemplateArgs = 0; 1343 } 1344} 1345 1346/// Diagnose an empty lookup. 1347/// 1348/// \return false if new lookup candidates were found 1349bool Sema::DiagnoseEmptyLookup(Scope *S, CXXScopeSpec &SS, LookupResult &R, 1350 CorrectionCandidateCallback &CCC, 1351 TemplateArgumentListInfo *ExplicitTemplateArgs, 1352 llvm::ArrayRef<Expr *> Args) { 1353 DeclarationName Name = R.getLookupName(); 1354 1355 unsigned diagnostic = diag::err_undeclared_var_use; 1356 unsigned diagnostic_suggest = diag::err_undeclared_var_use_suggest; 1357 if (Name.getNameKind() == DeclarationName::CXXOperatorName || 1358 Name.getNameKind() == DeclarationName::CXXLiteralOperatorName || 1359 Name.getNameKind() == DeclarationName::CXXConversionFunctionName) { 1360 diagnostic = diag::err_undeclared_use; 1361 diagnostic_suggest = diag::err_undeclared_use_suggest; 1362 } 1363 1364 // If the original lookup was an unqualified lookup, fake an 1365 // unqualified lookup. This is useful when (for example) the 1366 // original lookup would not have found something because it was a 1367 // dependent name. 1368 DeclContext *DC = SS.isEmpty() ? CurContext : 0; 1369 while (DC) { 1370 if (isa<CXXRecordDecl>(DC)) { 1371 LookupQualifiedName(R, DC); 1372 1373 if (!R.empty()) { 1374 // Don't give errors about ambiguities in this lookup. 1375 R.suppressDiagnostics(); 1376 1377 // During a default argument instantiation the CurContext points 1378 // to a CXXMethodDecl; but we can't apply a this-> fixit inside a 1379 // function parameter list, hence add an explicit check. 1380 bool isDefaultArgument = !ActiveTemplateInstantiations.empty() && 1381 ActiveTemplateInstantiations.back().Kind == 1382 ActiveTemplateInstantiation::DefaultFunctionArgumentInstantiation; 1383 CXXMethodDecl *CurMethod = dyn_cast<CXXMethodDecl>(CurContext); 1384 bool isInstance = CurMethod && 1385 CurMethod->isInstance() && 1386 DC == CurMethod->getParent() && !isDefaultArgument; 1387 1388 1389 // Give a code modification hint to insert 'this->'. 1390 // TODO: fixit for inserting 'Base<T>::' in the other cases. 1391 // Actually quite difficult! 1392 if (isInstance) { 1393 UnresolvedLookupExpr *ULE = cast<UnresolvedLookupExpr>( 1394 CallsUndergoingInstantiation.back()->getCallee()); 1395 CXXMethodDecl *DepMethod = cast_or_null<CXXMethodDecl>( 1396 CurMethod->getInstantiatedFromMemberFunction()); 1397 if (DepMethod) { 1398 if (getLangOpts().MicrosoftMode) 1399 diagnostic = diag::warn_found_via_dependent_bases_lookup; 1400 Diag(R.getNameLoc(), diagnostic) << Name 1401 << FixItHint::CreateInsertion(R.getNameLoc(), "this->"); 1402 QualType DepThisType = DepMethod->getThisType(Context); 1403 CheckCXXThisCapture(R.getNameLoc()); 1404 CXXThisExpr *DepThis = new (Context) CXXThisExpr( 1405 R.getNameLoc(), DepThisType, false); 1406 TemplateArgumentListInfo TList; 1407 if (ULE->hasExplicitTemplateArgs()) 1408 ULE->copyTemplateArgumentsInto(TList); 1409 1410 CXXScopeSpec SS; 1411 SS.Adopt(ULE->getQualifierLoc()); 1412 CXXDependentScopeMemberExpr *DepExpr = 1413 CXXDependentScopeMemberExpr::Create( 1414 Context, DepThis, DepThisType, true, SourceLocation(), 1415 SS.getWithLocInContext(Context), 1416 ULE->getTemplateKeywordLoc(), 0, 1417 R.getLookupNameInfo(), 1418 ULE->hasExplicitTemplateArgs() ? &TList : 0); 1419 CallsUndergoingInstantiation.back()->setCallee(DepExpr); 1420 } else { 1421 // FIXME: we should be able to handle this case too. It is correct 1422 // to add this-> here. This is a workaround for PR7947. 1423 Diag(R.getNameLoc(), diagnostic) << Name; 1424 } 1425 } else { 1426 if (getLangOpts().MicrosoftMode) 1427 diagnostic = diag::warn_found_via_dependent_bases_lookup; 1428 Diag(R.getNameLoc(), diagnostic) << Name; 1429 } 1430 1431 // Do we really want to note all of these? 1432 for (LookupResult::iterator I = R.begin(), E = R.end(); I != E; ++I) 1433 Diag((*I)->getLocation(), diag::note_dependent_var_use); 1434 1435 // Return true if we are inside a default argument instantiation 1436 // and the found name refers to an instance member function, otherwise 1437 // the function calling DiagnoseEmptyLookup will try to create an 1438 // implicit member call and this is wrong for default argument. 1439 if (isDefaultArgument && ((*R.begin())->isCXXInstanceMember())) { 1440 Diag(R.getNameLoc(), diag::err_member_call_without_object); 1441 return true; 1442 } 1443 1444 // Tell the callee to try to recover. 1445 return false; 1446 } 1447 1448 R.clear(); 1449 } 1450 1451 // In Microsoft mode, if we are performing lookup from within a friend 1452 // function definition declared at class scope then we must set 1453 // DC to the lexical parent to be able to search into the parent 1454 // class. 1455 if (getLangOpts().MicrosoftMode && isa<FunctionDecl>(DC) && 1456 cast<FunctionDecl>(DC)->getFriendObjectKind() && 1457 DC->getLexicalParent()->isRecord()) 1458 DC = DC->getLexicalParent(); 1459 else 1460 DC = DC->getParent(); 1461 } 1462 1463 // We didn't find anything, so try to correct for a typo. 1464 TypoCorrection Corrected; 1465 if (S && (Corrected = CorrectTypo(R.getLookupNameInfo(), R.getLookupKind(), 1466 S, &SS, CCC))) { 1467 std::string CorrectedStr(Corrected.getAsString(getLangOpts())); 1468 std::string CorrectedQuotedStr(Corrected.getQuoted(getLangOpts())); 1469 R.setLookupName(Corrected.getCorrection()); 1470 1471 if (NamedDecl *ND = Corrected.getCorrectionDecl()) { 1472 if (Corrected.isOverloaded()) { 1473 OverloadCandidateSet OCS(R.getNameLoc()); 1474 OverloadCandidateSet::iterator Best; 1475 for (TypoCorrection::decl_iterator CD = Corrected.begin(), 1476 CDEnd = Corrected.end(); 1477 CD != CDEnd; ++CD) { 1478 if (FunctionTemplateDecl *FTD = 1479 dyn_cast<FunctionTemplateDecl>(*CD)) 1480 AddTemplateOverloadCandidate( 1481 FTD, DeclAccessPair::make(FTD, AS_none), ExplicitTemplateArgs, 1482 Args, OCS); 1483 else if (FunctionDecl *FD = dyn_cast<FunctionDecl>(*CD)) 1484 if (!ExplicitTemplateArgs || ExplicitTemplateArgs->size() == 0) 1485 AddOverloadCandidate(FD, DeclAccessPair::make(FD, AS_none), 1486 Args, OCS); 1487 } 1488 switch (OCS.BestViableFunction(*this, R.getNameLoc(), Best)) { 1489 case OR_Success: 1490 ND = Best->Function; 1491 break; 1492 default: 1493 break; 1494 } 1495 } 1496 R.addDecl(ND); 1497 if (isa<ValueDecl>(ND) || isa<FunctionTemplateDecl>(ND)) { 1498 if (SS.isEmpty()) 1499 Diag(R.getNameLoc(), diagnostic_suggest) << Name << CorrectedQuotedStr 1500 << FixItHint::CreateReplacement(R.getNameLoc(), CorrectedStr); 1501 else 1502 Diag(R.getNameLoc(), diag::err_no_member_suggest) 1503 << Name << computeDeclContext(SS, false) << CorrectedQuotedStr 1504 << SS.getRange() 1505 << FixItHint::CreateReplacement(R.getNameLoc(), CorrectedStr); 1506 if (ND) 1507 Diag(ND->getLocation(), diag::note_previous_decl) 1508 << CorrectedQuotedStr; 1509 1510 // Tell the callee to try to recover. 1511 return false; 1512 } 1513 1514 if (isa<TypeDecl>(ND) || isa<ObjCInterfaceDecl>(ND)) { 1515 // FIXME: If we ended up with a typo for a type name or 1516 // Objective-C class name, we're in trouble because the parser 1517 // is in the wrong place to recover. Suggest the typo 1518 // correction, but don't make it a fix-it since we're not going 1519 // to recover well anyway. 1520 if (SS.isEmpty()) 1521 Diag(R.getNameLoc(), diagnostic_suggest) 1522 << Name << CorrectedQuotedStr; 1523 else 1524 Diag(R.getNameLoc(), diag::err_no_member_suggest) 1525 << Name << computeDeclContext(SS, false) << CorrectedQuotedStr 1526 << SS.getRange(); 1527 1528 // Don't try to recover; it won't work. 1529 return true; 1530 } 1531 } else { 1532 // FIXME: We found a keyword. Suggest it, but don't provide a fix-it 1533 // because we aren't able to recover. 1534 if (SS.isEmpty()) 1535 Diag(R.getNameLoc(), diagnostic_suggest) << Name << CorrectedQuotedStr; 1536 else 1537 Diag(R.getNameLoc(), diag::err_no_member_suggest) 1538 << Name << computeDeclContext(SS, false) << CorrectedQuotedStr 1539 << SS.getRange(); 1540 return true; 1541 } 1542 } 1543 R.clear(); 1544 1545 // Emit a special diagnostic for failed member lookups. 1546 // FIXME: computing the declaration context might fail here (?) 1547 if (!SS.isEmpty()) { 1548 Diag(R.getNameLoc(), diag::err_no_member) 1549 << Name << computeDeclContext(SS, false) 1550 << SS.getRange(); 1551 return true; 1552 } 1553 1554 // Give up, we can't recover. 1555 Diag(R.getNameLoc(), diagnostic) << Name; 1556 return true; 1557} 1558 1559ExprResult Sema::ActOnIdExpression(Scope *S, 1560 CXXScopeSpec &SS, 1561 SourceLocation TemplateKWLoc, 1562 UnqualifiedId &Id, 1563 bool HasTrailingLParen, 1564 bool IsAddressOfOperand, 1565 CorrectionCandidateCallback *CCC) { 1566 assert(!(IsAddressOfOperand && HasTrailingLParen) && 1567 "cannot be direct & operand and have a trailing lparen"); 1568 1569 if (SS.isInvalid()) 1570 return ExprError(); 1571 1572 TemplateArgumentListInfo TemplateArgsBuffer; 1573 1574 // Decompose the UnqualifiedId into the following data. 1575 DeclarationNameInfo NameInfo; 1576 const TemplateArgumentListInfo *TemplateArgs; 1577 DecomposeUnqualifiedId(Id, TemplateArgsBuffer, NameInfo, TemplateArgs); 1578 1579 DeclarationName Name = NameInfo.getName(); 1580 IdentifierInfo *II = Name.getAsIdentifierInfo(); 1581 SourceLocation NameLoc = NameInfo.getLoc(); 1582 1583 // C++ [temp.dep.expr]p3: 1584 // An id-expression is type-dependent if it contains: 1585 // -- an identifier that was declared with a dependent type, 1586 // (note: handled after lookup) 1587 // -- a template-id that is dependent, 1588 // (note: handled in BuildTemplateIdExpr) 1589 // -- a conversion-function-id that specifies a dependent type, 1590 // -- a nested-name-specifier that contains a class-name that 1591 // names a dependent type. 1592 // Determine whether this is a member of an unknown specialization; 1593 // we need to handle these differently. 1594 bool DependentID = false; 1595 if (Name.getNameKind() == DeclarationName::CXXConversionFunctionName && 1596 Name.getCXXNameType()->isDependentType()) { 1597 DependentID = true; 1598 } else if (SS.isSet()) { 1599 if (DeclContext *DC = computeDeclContext(SS, false)) { 1600 if (RequireCompleteDeclContext(SS, DC)) 1601 return ExprError(); 1602 } else { 1603 DependentID = true; 1604 } 1605 } 1606 1607 if (DependentID) 1608 return ActOnDependentIdExpression(SS, TemplateKWLoc, NameInfo, 1609 IsAddressOfOperand, TemplateArgs); 1610 1611 // Perform the required lookup. 1612 LookupResult R(*this, NameInfo, 1613 (Id.getKind() == UnqualifiedId::IK_ImplicitSelfParam) 1614 ? LookupObjCImplicitSelfParam : LookupOrdinaryName); 1615 if (TemplateArgs) { 1616 // Lookup the template name again to correctly establish the context in 1617 // which it was found. This is really unfortunate as we already did the 1618 // lookup to determine that it was a template name in the first place. If 1619 // this becomes a performance hit, we can work harder to preserve those 1620 // results until we get here but it's likely not worth it. 1621 bool MemberOfUnknownSpecialization; 1622 LookupTemplateName(R, S, SS, QualType(), /*EnteringContext=*/false, 1623 MemberOfUnknownSpecialization); 1624 1625 if (MemberOfUnknownSpecialization || 1626 (R.getResultKind() == LookupResult::NotFoundInCurrentInstantiation)) 1627 return ActOnDependentIdExpression(SS, TemplateKWLoc, NameInfo, 1628 IsAddressOfOperand, TemplateArgs); 1629 } else { 1630 bool IvarLookupFollowUp = II && !SS.isSet() && getCurMethodDecl(); 1631 LookupParsedName(R, S, &SS, !IvarLookupFollowUp); 1632 1633 // If the result might be in a dependent base class, this is a dependent 1634 // id-expression. 1635 if (R.getResultKind() == LookupResult::NotFoundInCurrentInstantiation) 1636 return ActOnDependentIdExpression(SS, TemplateKWLoc, NameInfo, 1637 IsAddressOfOperand, TemplateArgs); 1638 1639 // If this reference is in an Objective-C method, then we need to do 1640 // some special Objective-C lookup, too. 1641 if (IvarLookupFollowUp) { 1642 ExprResult E(LookupInObjCMethod(R, S, II, true)); 1643 if (E.isInvalid()) 1644 return ExprError(); 1645 1646 if (Expr *Ex = E.takeAs<Expr>()) 1647 return Owned(Ex); 1648 } 1649 } 1650 1651 if (R.isAmbiguous()) 1652 return ExprError(); 1653 1654 // Determine whether this name might be a candidate for 1655 // argument-dependent lookup. 1656 bool ADL = UseArgumentDependentLookup(SS, R, HasTrailingLParen); 1657 1658 if (R.empty() && !ADL) { 1659 // Otherwise, this could be an implicitly declared function reference (legal 1660 // in C90, extension in C99, forbidden in C++). 1661 if (HasTrailingLParen && II && !getLangOpts().CPlusPlus) { 1662 NamedDecl *D = ImplicitlyDefineFunction(NameLoc, *II, S); 1663 if (D) R.addDecl(D); 1664 } 1665 1666 // If this name wasn't predeclared and if this is not a function 1667 // call, diagnose the problem. 1668 if (R.empty()) { 1669 1670 // In Microsoft mode, if we are inside a template class member function 1671 // and we can't resolve an identifier then assume the identifier is type 1672 // dependent. The goal is to postpone name lookup to instantiation time 1673 // to be able to search into type dependent base classes. 1674 if (getLangOpts().MicrosoftMode && CurContext->isDependentContext() && 1675 isa<CXXMethodDecl>(CurContext)) 1676 return ActOnDependentIdExpression(SS, TemplateKWLoc, NameInfo, 1677 IsAddressOfOperand, TemplateArgs); 1678 1679 CorrectionCandidateCallback DefaultValidator; 1680 if (DiagnoseEmptyLookup(S, SS, R, CCC ? *CCC : DefaultValidator)) 1681 return ExprError(); 1682 1683 assert(!R.empty() && 1684 "DiagnoseEmptyLookup returned false but added no results"); 1685 1686 // If we found an Objective-C instance variable, let 1687 // LookupInObjCMethod build the appropriate expression to 1688 // reference the ivar. 1689 if (ObjCIvarDecl *Ivar = R.getAsSingle<ObjCIvarDecl>()) { 1690 R.clear(); 1691 ExprResult E(LookupInObjCMethod(R, S, Ivar->getIdentifier())); 1692 // In a hopelessly buggy code, Objective-C instance variable 1693 // lookup fails and no expression will be built to reference it. 1694 if (!E.isInvalid() && !E.get()) 1695 return ExprError(); 1696 return move(E); 1697 } 1698 } 1699 } 1700 1701 // This is guaranteed from this point on. 1702 assert(!R.empty() || ADL); 1703 1704 // Check whether this might be a C++ implicit instance member access. 1705 // C++ [class.mfct.non-static]p3: 1706 // When an id-expression that is not part of a class member access 1707 // syntax and not used to form a pointer to member is used in the 1708 // body of a non-static member function of class X, if name lookup 1709 // resolves the name in the id-expression to a non-static non-type 1710 // member of some class C, the id-expression is transformed into a 1711 // class member access expression using (*this) as the 1712 // postfix-expression to the left of the . operator. 1713 // 1714 // But we don't actually need to do this for '&' operands if R 1715 // resolved to a function or overloaded function set, because the 1716 // expression is ill-formed if it actually works out to be a 1717 // non-static member function: 1718 // 1719 // C++ [expr.ref]p4: 1720 // Otherwise, if E1.E2 refers to a non-static member function. . . 1721 // [t]he expression can be used only as the left-hand operand of a 1722 // member function call. 1723 // 1724 // There are other safeguards against such uses, but it's important 1725 // to get this right here so that we don't end up making a 1726 // spuriously dependent expression if we're inside a dependent 1727 // instance method. 1728 if (!R.empty() && (*R.begin())->isCXXClassMember()) { 1729 bool MightBeImplicitMember; 1730 if (!IsAddressOfOperand) 1731 MightBeImplicitMember = true; 1732 else if (!SS.isEmpty()) 1733 MightBeImplicitMember = false; 1734 else if (R.isOverloadedResult()) 1735 MightBeImplicitMember = false; 1736 else if (R.isUnresolvableResult()) 1737 MightBeImplicitMember = true; 1738 else 1739 MightBeImplicitMember = isa<FieldDecl>(R.getFoundDecl()) || 1740 isa<IndirectFieldDecl>(R.getFoundDecl()); 1741 1742 if (MightBeImplicitMember) 1743 return BuildPossibleImplicitMemberExpr(SS, TemplateKWLoc, 1744 R, TemplateArgs); 1745 } 1746 1747 if (TemplateArgs || TemplateKWLoc.isValid()) 1748 return BuildTemplateIdExpr(SS, TemplateKWLoc, R, ADL, TemplateArgs); 1749 1750 return BuildDeclarationNameExpr(SS, R, ADL); 1751} 1752 1753/// BuildQualifiedDeclarationNameExpr - Build a C++ qualified 1754/// declaration name, generally during template instantiation. 1755/// There's a large number of things which don't need to be done along 1756/// this path. 1757ExprResult 1758Sema::BuildQualifiedDeclarationNameExpr(CXXScopeSpec &SS, 1759 const DeclarationNameInfo &NameInfo) { 1760 DeclContext *DC; 1761 if (!(DC = computeDeclContext(SS, false)) || DC->isDependentContext()) 1762 return BuildDependentDeclRefExpr(SS, /*TemplateKWLoc=*/SourceLocation(), 1763 NameInfo, /*TemplateArgs=*/0); 1764 1765 if (RequireCompleteDeclContext(SS, DC)) 1766 return ExprError(); 1767 1768 LookupResult R(*this, NameInfo, LookupOrdinaryName); 1769 LookupQualifiedName(R, DC); 1770 1771 if (R.isAmbiguous()) 1772 return ExprError(); 1773 1774 if (R.empty()) { 1775 Diag(NameInfo.getLoc(), diag::err_no_member) 1776 << NameInfo.getName() << DC << SS.getRange(); 1777 return ExprError(); 1778 } 1779 1780 return BuildDeclarationNameExpr(SS, R, /*ADL*/ false); 1781} 1782 1783/// LookupInObjCMethod - The parser has read a name in, and Sema has 1784/// detected that we're currently inside an ObjC method. Perform some 1785/// additional lookup. 1786/// 1787/// Ideally, most of this would be done by lookup, but there's 1788/// actually quite a lot of extra work involved. 1789/// 1790/// Returns a null sentinel to indicate trivial success. 1791ExprResult 1792Sema::LookupInObjCMethod(LookupResult &Lookup, Scope *S, 1793 IdentifierInfo *II, bool AllowBuiltinCreation) { 1794 SourceLocation Loc = Lookup.getNameLoc(); 1795 ObjCMethodDecl *CurMethod = getCurMethodDecl(); 1796 1797 // There are two cases to handle here. 1) scoped lookup could have failed, 1798 // in which case we should look for an ivar. 2) scoped lookup could have 1799 // found a decl, but that decl is outside the current instance method (i.e. 1800 // a global variable). In these two cases, we do a lookup for an ivar with 1801 // this name, if the lookup sucedes, we replace it our current decl. 1802 1803 // If we're in a class method, we don't normally want to look for 1804 // ivars. But if we don't find anything else, and there's an 1805 // ivar, that's an error. 1806 bool IsClassMethod = CurMethod->isClassMethod(); 1807 1808 bool LookForIvars; 1809 if (Lookup.empty()) 1810 LookForIvars = true; 1811 else if (IsClassMethod) 1812 LookForIvars = false; 1813 else 1814 LookForIvars = (Lookup.isSingleResult() && 1815 Lookup.getFoundDecl()->isDefinedOutsideFunctionOrMethod()); 1816 ObjCInterfaceDecl *IFace = 0; 1817 if (LookForIvars) { 1818 IFace = CurMethod->getClassInterface(); 1819 ObjCInterfaceDecl *ClassDeclared; 1820 ObjCIvarDecl *IV = 0; 1821 if (IFace && (IV = IFace->lookupInstanceVariable(II, ClassDeclared))) { 1822 // Diagnose using an ivar in a class method. 1823 if (IsClassMethod) 1824 return ExprError(Diag(Loc, diag::error_ivar_use_in_class_method) 1825 << IV->getDeclName()); 1826 1827 // If we're referencing an invalid decl, just return this as a silent 1828 // error node. The error diagnostic was already emitted on the decl. 1829 if (IV->isInvalidDecl()) 1830 return ExprError(); 1831 1832 // Check if referencing a field with __attribute__((deprecated)). 1833 if (DiagnoseUseOfDecl(IV, Loc)) 1834 return ExprError(); 1835 1836 // Diagnose the use of an ivar outside of the declaring class. 1837 if (IV->getAccessControl() == ObjCIvarDecl::Private && 1838 !declaresSameEntity(ClassDeclared, IFace) && 1839 !getLangOpts().DebuggerSupport) 1840 Diag(Loc, diag::error_private_ivar_access) << IV->getDeclName(); 1841 1842 // FIXME: This should use a new expr for a direct reference, don't 1843 // turn this into Self->ivar, just return a BareIVarExpr or something. 1844 IdentifierInfo &II = Context.Idents.get("self"); 1845 UnqualifiedId SelfName; 1846 SelfName.setIdentifier(&II, SourceLocation()); 1847 SelfName.setKind(UnqualifiedId::IK_ImplicitSelfParam); 1848 CXXScopeSpec SelfScopeSpec; 1849 SourceLocation TemplateKWLoc; 1850 ExprResult SelfExpr = ActOnIdExpression(S, SelfScopeSpec, TemplateKWLoc, 1851 SelfName, false, false); 1852 if (SelfExpr.isInvalid()) 1853 return ExprError(); 1854 1855 SelfExpr = DefaultLvalueConversion(SelfExpr.take()); 1856 if (SelfExpr.isInvalid()) 1857 return ExprError(); 1858 1859 MarkAnyDeclReferenced(Loc, IV); 1860 return Owned(new (Context) 1861 ObjCIvarRefExpr(IV, IV->getType(), Loc, 1862 SelfExpr.take(), true, true)); 1863 } 1864 } else if (CurMethod->isInstanceMethod()) { 1865 // We should warn if a local variable hides an ivar. 1866 if (ObjCInterfaceDecl *IFace = CurMethod->getClassInterface()) { 1867 ObjCInterfaceDecl *ClassDeclared; 1868 if (ObjCIvarDecl *IV = IFace->lookupInstanceVariable(II, ClassDeclared)) { 1869 if (IV->getAccessControl() != ObjCIvarDecl::Private || 1870 declaresSameEntity(IFace, ClassDeclared)) 1871 Diag(Loc, diag::warn_ivar_use_hidden) << IV->getDeclName(); 1872 } 1873 } 1874 } else if (Lookup.isSingleResult() && 1875 Lookup.getFoundDecl()->isDefinedOutsideFunctionOrMethod()) { 1876 // If accessing a stand-alone ivar in a class method, this is an error. 1877 if (const ObjCIvarDecl *IV = dyn_cast<ObjCIvarDecl>(Lookup.getFoundDecl())) 1878 return ExprError(Diag(Loc, diag::error_ivar_use_in_class_method) 1879 << IV->getDeclName()); 1880 } 1881 1882 if (Lookup.empty() && II && AllowBuiltinCreation) { 1883 // FIXME. Consolidate this with similar code in LookupName. 1884 if (unsigned BuiltinID = II->getBuiltinID()) { 1885 if (!(getLangOpts().CPlusPlus && 1886 Context.BuiltinInfo.isPredefinedLibFunction(BuiltinID))) { 1887 NamedDecl *D = LazilyCreateBuiltin((IdentifierInfo *)II, BuiltinID, 1888 S, Lookup.isForRedeclaration(), 1889 Lookup.getNameLoc()); 1890 if (D) Lookup.addDecl(D); 1891 } 1892 } 1893 } 1894 // Sentinel value saying that we didn't do anything special. 1895 return Owned((Expr*) 0); 1896} 1897 1898/// \brief Cast a base object to a member's actual type. 1899/// 1900/// Logically this happens in three phases: 1901/// 1902/// * First we cast from the base type to the naming class. 1903/// The naming class is the class into which we were looking 1904/// when we found the member; it's the qualifier type if a 1905/// qualifier was provided, and otherwise it's the base type. 1906/// 1907/// * Next we cast from the naming class to the declaring class. 1908/// If the member we found was brought into a class's scope by 1909/// a using declaration, this is that class; otherwise it's 1910/// the class declaring the member. 1911/// 1912/// * Finally we cast from the declaring class to the "true" 1913/// declaring class of the member. This conversion does not 1914/// obey access control. 1915ExprResult 1916Sema::PerformObjectMemberConversion(Expr *From, 1917 NestedNameSpecifier *Qualifier, 1918 NamedDecl *FoundDecl, 1919 NamedDecl *Member) { 1920 CXXRecordDecl *RD = dyn_cast<CXXRecordDecl>(Member->getDeclContext()); 1921 if (!RD) 1922 return Owned(From); 1923 1924 QualType DestRecordType; 1925 QualType DestType; 1926 QualType FromRecordType; 1927 QualType FromType = From->getType(); 1928 bool PointerConversions = false; 1929 if (isa<FieldDecl>(Member)) { 1930 DestRecordType = Context.getCanonicalType(Context.getTypeDeclType(RD)); 1931 1932 if (FromType->getAs<PointerType>()) { 1933 DestType = Context.getPointerType(DestRecordType); 1934 FromRecordType = FromType->getPointeeType(); 1935 PointerConversions = true; 1936 } else { 1937 DestType = DestRecordType; 1938 FromRecordType = FromType; 1939 } 1940 } else if (CXXMethodDecl *Method = dyn_cast<CXXMethodDecl>(Member)) { 1941 if (Method->isStatic()) 1942 return Owned(From); 1943 1944 DestType = Method->getThisType(Context); 1945 DestRecordType = DestType->getPointeeType(); 1946 1947 if (FromType->getAs<PointerType>()) { 1948 FromRecordType = FromType->getPointeeType(); 1949 PointerConversions = true; 1950 } else { 1951 FromRecordType = FromType; 1952 DestType = DestRecordType; 1953 } 1954 } else { 1955 // No conversion necessary. 1956 return Owned(From); 1957 } 1958 1959 if (DestType->isDependentType() || FromType->isDependentType()) 1960 return Owned(From); 1961 1962 // If the unqualified types are the same, no conversion is necessary. 1963 if (Context.hasSameUnqualifiedType(FromRecordType, DestRecordType)) 1964 return Owned(From); 1965 1966 SourceRange FromRange = From->getSourceRange(); 1967 SourceLocation FromLoc = FromRange.getBegin(); 1968 1969 ExprValueKind VK = From->getValueKind(); 1970 1971 // C++ [class.member.lookup]p8: 1972 // [...] Ambiguities can often be resolved by qualifying a name with its 1973 // class name. 1974 // 1975 // If the member was a qualified name and the qualified referred to a 1976 // specific base subobject type, we'll cast to that intermediate type 1977 // first and then to the object in which the member is declared. That allows 1978 // one to resolve ambiguities in, e.g., a diamond-shaped hierarchy such as: 1979 // 1980 // class Base { public: int x; }; 1981 // class Derived1 : public Base { }; 1982 // class Derived2 : public Base { }; 1983 // class VeryDerived : public Derived1, public Derived2 { void f(); }; 1984 // 1985 // void VeryDerived::f() { 1986 // x = 17; // error: ambiguous base subobjects 1987 // Derived1::x = 17; // okay, pick the Base subobject of Derived1 1988 // } 1989 if (Qualifier) { 1990 QualType QType = QualType(Qualifier->getAsType(), 0); 1991 assert(!QType.isNull() && "lookup done with dependent qualifier?"); 1992 assert(QType->isRecordType() && "lookup done with non-record type"); 1993 1994 QualType QRecordType = QualType(QType->getAs<RecordType>(), 0); 1995 1996 // In C++98, the qualifier type doesn't actually have to be a base 1997 // type of the object type, in which case we just ignore it. 1998 // Otherwise build the appropriate casts. 1999 if (IsDerivedFrom(FromRecordType, QRecordType)) { 2000 CXXCastPath BasePath; 2001 if (CheckDerivedToBaseConversion(FromRecordType, QRecordType, 2002 FromLoc, FromRange, &BasePath)) 2003 return ExprError(); 2004 2005 if (PointerConversions) 2006 QType = Context.getPointerType(QType); 2007 From = ImpCastExprToType(From, QType, CK_UncheckedDerivedToBase, 2008 VK, &BasePath).take(); 2009 2010 FromType = QType; 2011 FromRecordType = QRecordType; 2012 2013 // If the qualifier type was the same as the destination type, 2014 // we're done. 2015 if (Context.hasSameUnqualifiedType(FromRecordType, DestRecordType)) 2016 return Owned(From); 2017 } 2018 } 2019 2020 bool IgnoreAccess = false; 2021 2022 // If we actually found the member through a using declaration, cast 2023 // down to the using declaration's type. 2024 // 2025 // Pointer equality is fine here because only one declaration of a 2026 // class ever has member declarations. 2027 if (FoundDecl->getDeclContext() != Member->getDeclContext()) { 2028 assert(isa<UsingShadowDecl>(FoundDecl)); 2029 QualType URecordType = Context.getTypeDeclType( 2030 cast<CXXRecordDecl>(FoundDecl->getDeclContext())); 2031 2032 // We only need to do this if the naming-class to declaring-class 2033 // conversion is non-trivial. 2034 if (!Context.hasSameUnqualifiedType(FromRecordType, URecordType)) { 2035 assert(IsDerivedFrom(FromRecordType, URecordType)); 2036 CXXCastPath BasePath; 2037 if (CheckDerivedToBaseConversion(FromRecordType, URecordType, 2038 FromLoc, FromRange, &BasePath)) 2039 return ExprError(); 2040 2041 QualType UType = URecordType; 2042 if (PointerConversions) 2043 UType = Context.getPointerType(UType); 2044 From = ImpCastExprToType(From, UType, CK_UncheckedDerivedToBase, 2045 VK, &BasePath).take(); 2046 FromType = UType; 2047 FromRecordType = URecordType; 2048 } 2049 2050 // We don't do access control for the conversion from the 2051 // declaring class to the true declaring class. 2052 IgnoreAccess = true; 2053 } 2054 2055 CXXCastPath BasePath; 2056 if (CheckDerivedToBaseConversion(FromRecordType, DestRecordType, 2057 FromLoc, FromRange, &BasePath, 2058 IgnoreAccess)) 2059 return ExprError(); 2060 2061 return ImpCastExprToType(From, DestType, CK_UncheckedDerivedToBase, 2062 VK, &BasePath); 2063} 2064 2065bool Sema::UseArgumentDependentLookup(const CXXScopeSpec &SS, 2066 const LookupResult &R, 2067 bool HasTrailingLParen) { 2068 // Only when used directly as the postfix-expression of a call. 2069 if (!HasTrailingLParen) 2070 return false; 2071 2072 // Never if a scope specifier was provided. 2073 if (SS.isSet()) 2074 return false; 2075 2076 // Only in C++ or ObjC++. 2077 if (!getLangOpts().CPlusPlus) 2078 return false; 2079 2080 // Turn off ADL when we find certain kinds of declarations during 2081 // normal lookup: 2082 for (LookupResult::iterator I = R.begin(), E = R.end(); I != E; ++I) { 2083 NamedDecl *D = *I; 2084 2085 // C++0x [basic.lookup.argdep]p3: 2086 // -- a declaration of a class member 2087 // Since using decls preserve this property, we check this on the 2088 // original decl. 2089 if (D->isCXXClassMember()) 2090 return false; 2091 2092 // C++0x [basic.lookup.argdep]p3: 2093 // -- a block-scope function declaration that is not a 2094 // using-declaration 2095 // NOTE: we also trigger this for function templates (in fact, we 2096 // don't check the decl type at all, since all other decl types 2097 // turn off ADL anyway). 2098 if (isa<UsingShadowDecl>(D)) 2099 D = cast<UsingShadowDecl>(D)->getTargetDecl(); 2100 else if (D->getDeclContext()->isFunctionOrMethod()) 2101 return false; 2102 2103 // C++0x [basic.lookup.argdep]p3: 2104 // -- a declaration that is neither a function or a function 2105 // template 2106 // And also for builtin functions. 2107 if (isa<FunctionDecl>(D)) { 2108 FunctionDecl *FDecl = cast<FunctionDecl>(D); 2109 2110 // But also builtin functions. 2111 if (FDecl->getBuiltinID() && FDecl->isImplicit()) 2112 return false; 2113 } else if (!isa<FunctionTemplateDecl>(D)) 2114 return false; 2115 } 2116 2117 return true; 2118} 2119 2120 2121/// Diagnoses obvious problems with the use of the given declaration 2122/// as an expression. This is only actually called for lookups that 2123/// were not overloaded, and it doesn't promise that the declaration 2124/// will in fact be used. 2125static bool CheckDeclInExpr(Sema &S, SourceLocation Loc, NamedDecl *D) { 2126 if (isa<TypedefNameDecl>(D)) { 2127 S.Diag(Loc, diag::err_unexpected_typedef) << D->getDeclName(); 2128 return true; 2129 } 2130 2131 if (isa<ObjCInterfaceDecl>(D)) { 2132 S.Diag(Loc, diag::err_unexpected_interface) << D->getDeclName(); 2133 return true; 2134 } 2135 2136 if (isa<NamespaceDecl>(D)) { 2137 S.Diag(Loc, diag::err_unexpected_namespace) << D->getDeclName(); 2138 return true; 2139 } 2140 2141 return false; 2142} 2143 2144ExprResult 2145Sema::BuildDeclarationNameExpr(const CXXScopeSpec &SS, 2146 LookupResult &R, 2147 bool NeedsADL) { 2148 // If this is a single, fully-resolved result and we don't need ADL, 2149 // just build an ordinary singleton decl ref. 2150 if (!NeedsADL && R.isSingleResult() && !R.getAsSingle<FunctionTemplateDecl>()) 2151 return BuildDeclarationNameExpr(SS, R.getLookupNameInfo(), 2152 R.getFoundDecl()); 2153 2154 // We only need to check the declaration if there's exactly one 2155 // result, because in the overloaded case the results can only be 2156 // functions and function templates. 2157 if (R.isSingleResult() && 2158 CheckDeclInExpr(*this, R.getNameLoc(), R.getFoundDecl())) 2159 return ExprError(); 2160 2161 // Otherwise, just build an unresolved lookup expression. Suppress 2162 // any lookup-related diagnostics; we'll hash these out later, when 2163 // we've picked a target. 2164 R.suppressDiagnostics(); 2165 2166 UnresolvedLookupExpr *ULE 2167 = UnresolvedLookupExpr::Create(Context, R.getNamingClass(), 2168 SS.getWithLocInContext(Context), 2169 R.getLookupNameInfo(), 2170 NeedsADL, R.isOverloadedResult(), 2171 R.begin(), R.end()); 2172 2173 return Owned(ULE); 2174} 2175 2176/// \brief Complete semantic analysis for a reference to the given declaration. 2177ExprResult 2178Sema::BuildDeclarationNameExpr(const CXXScopeSpec &SS, 2179 const DeclarationNameInfo &NameInfo, 2180 NamedDecl *D) { 2181 assert(D && "Cannot refer to a NULL declaration"); 2182 assert(!isa<FunctionTemplateDecl>(D) && 2183 "Cannot refer unambiguously to a function template"); 2184 2185 SourceLocation Loc = NameInfo.getLoc(); 2186 if (CheckDeclInExpr(*this, Loc, D)) 2187 return ExprError(); 2188 2189 if (TemplateDecl *Template = dyn_cast<TemplateDecl>(D)) { 2190 // Specifically diagnose references to class templates that are missing 2191 // a template argument list. 2192 Diag(Loc, diag::err_template_decl_ref) 2193 << Template << SS.getRange(); 2194 Diag(Template->getLocation(), diag::note_template_decl_here); 2195 return ExprError(); 2196 } 2197 2198 // Make sure that we're referring to a value. 2199 ValueDecl *VD = dyn_cast<ValueDecl>(D); 2200 if (!VD) { 2201 Diag(Loc, diag::err_ref_non_value) 2202 << D << SS.getRange(); 2203 Diag(D->getLocation(), diag::note_declared_at); 2204 return ExprError(); 2205 } 2206 2207 // Check whether this declaration can be used. Note that we suppress 2208 // this check when we're going to perform argument-dependent lookup 2209 // on this function name, because this might not be the function 2210 // that overload resolution actually selects. 2211 if (DiagnoseUseOfDecl(VD, Loc)) 2212 return ExprError(); 2213 2214 // Only create DeclRefExpr's for valid Decl's. 2215 if (VD->isInvalidDecl()) 2216 return ExprError(); 2217 2218 // Handle members of anonymous structs and unions. If we got here, 2219 // and the reference is to a class member indirect field, then this 2220 // must be the subject of a pointer-to-member expression. 2221 if (IndirectFieldDecl *indirectField = dyn_cast<IndirectFieldDecl>(VD)) 2222 if (!indirectField->isCXXClassMember()) 2223 return BuildAnonymousStructUnionMemberReference(SS, NameInfo.getLoc(), 2224 indirectField); 2225 2226 { 2227 QualType type = VD->getType(); 2228 ExprValueKind valueKind = VK_RValue; 2229 2230 switch (D->getKind()) { 2231 // Ignore all the non-ValueDecl kinds. 2232#define ABSTRACT_DECL(kind) 2233#define VALUE(type, base) 2234#define DECL(type, base) \ 2235 case Decl::type: 2236#include "clang/AST/DeclNodes.inc" 2237 llvm_unreachable("invalid value decl kind"); 2238 2239 // These shouldn't make it here. 2240 case Decl::ObjCAtDefsField: 2241 case Decl::ObjCIvar: 2242 llvm_unreachable("forming non-member reference to ivar?"); 2243 2244 // Enum constants are always r-values and never references. 2245 // Unresolved using declarations are dependent. 2246 case Decl::EnumConstant: 2247 case Decl::UnresolvedUsingValue: 2248 valueKind = VK_RValue; 2249 break; 2250 2251 // Fields and indirect fields that got here must be for 2252 // pointer-to-member expressions; we just call them l-values for 2253 // internal consistency, because this subexpression doesn't really 2254 // exist in the high-level semantics. 2255 case Decl::Field: 2256 case Decl::IndirectField: 2257 assert(getLangOpts().CPlusPlus && 2258 "building reference to field in C?"); 2259 2260 // These can't have reference type in well-formed programs, but 2261 // for internal consistency we do this anyway. 2262 type = type.getNonReferenceType(); 2263 valueKind = VK_LValue; 2264 break; 2265 2266 // Non-type template parameters are either l-values or r-values 2267 // depending on the type. 2268 case Decl::NonTypeTemplateParm: { 2269 if (const ReferenceType *reftype = type->getAs<ReferenceType>()) { 2270 type = reftype->getPointeeType(); 2271 valueKind = VK_LValue; // even if the parameter is an r-value reference 2272 break; 2273 } 2274 2275 // For non-references, we need to strip qualifiers just in case 2276 // the template parameter was declared as 'const int' or whatever. 2277 valueKind = VK_RValue; 2278 type = type.getUnqualifiedType(); 2279 break; 2280 } 2281 2282 case Decl::Var: 2283 // In C, "extern void blah;" is valid and is an r-value. 2284 if (!getLangOpts().CPlusPlus && 2285 !type.hasQualifiers() && 2286 type->isVoidType()) { 2287 valueKind = VK_RValue; 2288 break; 2289 } 2290 // fallthrough 2291 2292 case Decl::ImplicitParam: 2293 case Decl::ParmVar: { 2294 // These are always l-values. 2295 valueKind = VK_LValue; 2296 type = type.getNonReferenceType(); 2297 2298 // FIXME: Does the addition of const really only apply in 2299 // potentially-evaluated contexts? Since the variable isn't actually 2300 // captured in an unevaluated context, it seems that the answer is no. 2301 if (ExprEvalContexts.back().Context != Sema::Unevaluated) { 2302 QualType CapturedType = getCapturedDeclRefType(cast<VarDecl>(VD), Loc); 2303 if (!CapturedType.isNull()) 2304 type = CapturedType; 2305 } 2306 2307 break; 2308 } 2309 2310 case Decl::Function: { 2311 const FunctionType *fty = type->castAs<FunctionType>(); 2312 2313 // If we're referring to a function with an __unknown_anytype 2314 // result type, make the entire expression __unknown_anytype. 2315 if (fty->getResultType() == Context.UnknownAnyTy) { 2316 type = Context.UnknownAnyTy; 2317 valueKind = VK_RValue; 2318 break; 2319 } 2320 2321 // Functions are l-values in C++. 2322 if (getLangOpts().CPlusPlus) { 2323 valueKind = VK_LValue; 2324 break; 2325 } 2326 2327 // C99 DR 316 says that, if a function type comes from a 2328 // function definition (without a prototype), that type is only 2329 // used for checking compatibility. Therefore, when referencing 2330 // the function, we pretend that we don't have the full function 2331 // type. 2332 if (!cast<FunctionDecl>(VD)->hasPrototype() && 2333 isa<FunctionProtoType>(fty)) 2334 type = Context.getFunctionNoProtoType(fty->getResultType(), 2335 fty->getExtInfo()); 2336 2337 // Functions are r-values in C. 2338 valueKind = VK_RValue; 2339 break; 2340 } 2341 2342 case Decl::CXXMethod: 2343 // If we're referring to a method with an __unknown_anytype 2344 // result type, make the entire expression __unknown_anytype. 2345 // This should only be possible with a type written directly. 2346 if (const FunctionProtoType *proto 2347 = dyn_cast<FunctionProtoType>(VD->getType())) 2348 if (proto->getResultType() == Context.UnknownAnyTy) { 2349 type = Context.UnknownAnyTy; 2350 valueKind = VK_RValue; 2351 break; 2352 } 2353 2354 // C++ methods are l-values if static, r-values if non-static. 2355 if (cast<CXXMethodDecl>(VD)->isStatic()) { 2356 valueKind = VK_LValue; 2357 break; 2358 } 2359 // fallthrough 2360 2361 case Decl::CXXConversion: 2362 case Decl::CXXDestructor: 2363 case Decl::CXXConstructor: 2364 valueKind = VK_RValue; 2365 break; 2366 } 2367 2368 return BuildDeclRefExpr(VD, type, valueKind, NameInfo, &SS); 2369 } 2370} 2371 2372ExprResult Sema::ActOnPredefinedExpr(SourceLocation Loc, tok::TokenKind Kind) { 2373 PredefinedExpr::IdentType IT; 2374 2375 switch (Kind) { 2376 default: llvm_unreachable("Unknown simple primary expr!"); 2377 case tok::kw___func__: IT = PredefinedExpr::Func; break; // [C99 6.4.2.2] 2378 case tok::kw___FUNCTION__: IT = PredefinedExpr::Function; break; 2379 case tok::kw___PRETTY_FUNCTION__: IT = PredefinedExpr::PrettyFunction; break; 2380 } 2381 2382 // Pre-defined identifiers are of type char[x], where x is the length of the 2383 // string. 2384 2385 Decl *currentDecl = getCurFunctionOrMethodDecl(); 2386 if (!currentDecl && getCurBlock()) 2387 currentDecl = getCurBlock()->TheDecl; 2388 if (!currentDecl) { 2389 Diag(Loc, diag::ext_predef_outside_function); 2390 currentDecl = Context.getTranslationUnitDecl(); 2391 } 2392 2393 QualType ResTy; 2394 if (cast<DeclContext>(currentDecl)->isDependentContext()) { 2395 ResTy = Context.DependentTy; 2396 } else { 2397 unsigned Length = PredefinedExpr::ComputeName(IT, currentDecl).length(); 2398 2399 llvm::APInt LengthI(32, Length + 1); 2400 ResTy = Context.CharTy.withConst(); 2401 ResTy = Context.getConstantArrayType(ResTy, LengthI, ArrayType::Normal, 0); 2402 } 2403 return Owned(new (Context) PredefinedExpr(Loc, ResTy, IT)); 2404} 2405 2406ExprResult Sema::ActOnCharacterConstant(const Token &Tok, Scope *UDLScope) { 2407 SmallString<16> CharBuffer; 2408 bool Invalid = false; 2409 StringRef ThisTok = PP.getSpelling(Tok, CharBuffer, &Invalid); 2410 if (Invalid) 2411 return ExprError(); 2412 2413 CharLiteralParser Literal(ThisTok.begin(), ThisTok.end(), Tok.getLocation(), 2414 PP, Tok.getKind()); 2415 if (Literal.hadError()) 2416 return ExprError(); 2417 2418 QualType Ty; 2419 if (Literal.isWide()) 2420 Ty = Context.WCharTy; // L'x' -> wchar_t in C and C++. 2421 else if (Literal.isUTF16()) 2422 Ty = Context.Char16Ty; // u'x' -> char16_t in C11 and C++11. 2423 else if (Literal.isUTF32()) 2424 Ty = Context.Char32Ty; // U'x' -> char32_t in C11 and C++11. 2425 else if (!getLangOpts().CPlusPlus || Literal.isMultiChar()) 2426 Ty = Context.IntTy; // 'x' -> int in C, 'wxyz' -> int in C++. 2427 else 2428 Ty = Context.CharTy; // 'x' -> char in C++ 2429 2430 CharacterLiteral::CharacterKind Kind = CharacterLiteral::Ascii; 2431 if (Literal.isWide()) 2432 Kind = CharacterLiteral::Wide; 2433 else if (Literal.isUTF16()) 2434 Kind = CharacterLiteral::UTF16; 2435 else if (Literal.isUTF32()) 2436 Kind = CharacterLiteral::UTF32; 2437 2438 Expr *Lit = new (Context) CharacterLiteral(Literal.getValue(), Kind, Ty, 2439 Tok.getLocation()); 2440 2441 if (Literal.getUDSuffix().empty()) 2442 return Owned(Lit); 2443 2444 // We're building a user-defined literal. 2445 IdentifierInfo *UDSuffix = &Context.Idents.get(Literal.getUDSuffix()); 2446 SourceLocation UDSuffixLoc = 2447 getUDSuffixLoc(*this, Tok.getLocation(), Literal.getUDSuffixOffset()); 2448 2449 // Make sure we're allowed user-defined literals here. 2450 if (!UDLScope) 2451 return ExprError(Diag(UDSuffixLoc, diag::err_invalid_character_udl)); 2452 2453 // C++11 [lex.ext]p6: The literal L is treated as a call of the form 2454 // operator "" X (ch) 2455 return BuildCookedLiteralOperatorCall(*this, UDLScope, UDSuffix, UDSuffixLoc, 2456 llvm::makeArrayRef(&Lit, 1), 2457 Tok.getLocation()); 2458} 2459 2460ExprResult Sema::ActOnIntegerConstant(SourceLocation Loc, uint64_t Val) { 2461 unsigned IntSize = Context.getTargetInfo().getIntWidth(); 2462 return Owned(IntegerLiteral::Create(Context, llvm::APInt(IntSize, Val), 2463 Context.IntTy, Loc)); 2464} 2465 2466static Expr *BuildFloatingLiteral(Sema &S, NumericLiteralParser &Literal, 2467 QualType Ty, SourceLocation Loc) { 2468 const llvm::fltSemantics &Format = S.Context.getFloatTypeSemantics(Ty); 2469 2470 using llvm::APFloat; 2471 APFloat Val(Format); 2472 2473 APFloat::opStatus result = Literal.GetFloatValue(Val); 2474 2475 // Overflow is always an error, but underflow is only an error if 2476 // we underflowed to zero (APFloat reports denormals as underflow). 2477 if ((result & APFloat::opOverflow) || 2478 ((result & APFloat::opUnderflow) && Val.isZero())) { 2479 unsigned diagnostic; 2480 SmallString<20> buffer; 2481 if (result & APFloat::opOverflow) { 2482 diagnostic = diag::warn_float_overflow; 2483 APFloat::getLargest(Format).toString(buffer); 2484 } else { 2485 diagnostic = diag::warn_float_underflow; 2486 APFloat::getSmallest(Format).toString(buffer); 2487 } 2488 2489 S.Diag(Loc, diagnostic) 2490 << Ty 2491 << StringRef(buffer.data(), buffer.size()); 2492 } 2493 2494 bool isExact = (result == APFloat::opOK); 2495 return FloatingLiteral::Create(S.Context, Val, isExact, Ty, Loc); 2496} 2497 2498ExprResult Sema::ActOnNumericConstant(const Token &Tok, Scope *UDLScope) { 2499 // Fast path for a single digit (which is quite common). A single digit 2500 // cannot have a trigraph, escaped newline, radix prefix, or suffix. 2501 if (Tok.getLength() == 1) { 2502 const char Val = PP.getSpellingOfSingleCharacterNumericConstant(Tok); 2503 return ActOnIntegerConstant(Tok.getLocation(), Val-'0'); 2504 } 2505 2506 SmallString<512> IntegerBuffer; 2507 // Add padding so that NumericLiteralParser can overread by one character. 2508 IntegerBuffer.resize(Tok.getLength()+1); 2509 const char *ThisTokBegin = &IntegerBuffer[0]; 2510 2511 // Get the spelling of the token, which eliminates trigraphs, etc. 2512 bool Invalid = false; 2513 unsigned ActualLength = PP.getSpelling(Tok, ThisTokBegin, &Invalid); 2514 if (Invalid) 2515 return ExprError(); 2516 2517 NumericLiteralParser Literal(ThisTokBegin, ThisTokBegin+ActualLength, 2518 Tok.getLocation(), PP); 2519 if (Literal.hadError) 2520 return ExprError(); 2521 2522 if (Literal.hasUDSuffix()) { 2523 // We're building a user-defined literal. 2524 IdentifierInfo *UDSuffix = &Context.Idents.get(Literal.getUDSuffix()); 2525 SourceLocation UDSuffixLoc = 2526 getUDSuffixLoc(*this, Tok.getLocation(), Literal.getUDSuffixOffset()); 2527 2528 // Make sure we're allowed user-defined literals here. 2529 if (!UDLScope) 2530 return ExprError(Diag(UDSuffixLoc, diag::err_invalid_numeric_udl)); 2531 2532 QualType CookedTy; 2533 if (Literal.isFloatingLiteral()) { 2534 // C++11 [lex.ext]p4: If S contains a literal operator with parameter type 2535 // long double, the literal is treated as a call of the form 2536 // operator "" X (f L) 2537 CookedTy = Context.LongDoubleTy; 2538 } else { 2539 // C++11 [lex.ext]p3: If S contains a literal operator with parameter type 2540 // unsigned long long, the literal is treated as a call of the form 2541 // operator "" X (n ULL) 2542 CookedTy = Context.UnsignedLongLongTy; 2543 } 2544 2545 DeclarationName OpName = 2546 Context.DeclarationNames.getCXXLiteralOperatorName(UDSuffix); 2547 DeclarationNameInfo OpNameInfo(OpName, UDSuffixLoc); 2548 OpNameInfo.setCXXLiteralOperatorNameLoc(UDSuffixLoc); 2549 2550 // Perform literal operator lookup to determine if we're building a raw 2551 // literal or a cooked one. 2552 LookupResult R(*this, OpName, UDSuffixLoc, LookupOrdinaryName); 2553 switch (LookupLiteralOperator(UDLScope, R, llvm::makeArrayRef(&CookedTy, 1), 2554 /*AllowRawAndTemplate*/true)) { 2555 case LOLR_Error: 2556 return ExprError(); 2557 2558 case LOLR_Cooked: { 2559 Expr *Lit; 2560 if (Literal.isFloatingLiteral()) { 2561 Lit = BuildFloatingLiteral(*this, Literal, CookedTy, Tok.getLocation()); 2562 } else { 2563 llvm::APInt ResultVal(Context.getTargetInfo().getLongLongWidth(), 0); 2564 if (Literal.GetIntegerValue(ResultVal)) 2565 Diag(Tok.getLocation(), diag::warn_integer_too_large); 2566 Lit = IntegerLiteral::Create(Context, ResultVal, CookedTy, 2567 Tok.getLocation()); 2568 } 2569 return BuildLiteralOperatorCall(R, OpNameInfo, 2570 llvm::makeArrayRef(&Lit, 1), 2571 Tok.getLocation()); 2572 } 2573 2574 case LOLR_Raw: { 2575 // C++11 [lit.ext]p3, p4: If S contains a raw literal operator, the 2576 // literal is treated as a call of the form 2577 // operator "" X ("n") 2578 SourceLocation TokLoc = Tok.getLocation(); 2579 unsigned Length = Literal.getUDSuffixOffset(); 2580 QualType StrTy = Context.getConstantArrayType( 2581 Context.CharTy, llvm::APInt(32, Length + 1), 2582 ArrayType::Normal, 0); 2583 Expr *Lit = StringLiteral::Create( 2584 Context, StringRef(ThisTokBegin, Length), StringLiteral::Ascii, 2585 /*Pascal*/false, StrTy, &TokLoc, 1); 2586 return BuildLiteralOperatorCall(R, OpNameInfo, 2587 llvm::makeArrayRef(&Lit, 1), TokLoc); 2588 } 2589 2590 case LOLR_Template: 2591 // C++11 [lit.ext]p3, p4: Otherwise (S contains a literal operator 2592 // template), L is treated as a call fo the form 2593 // operator "" X <'c1', 'c2', ... 'ck'>() 2594 // where n is the source character sequence c1 c2 ... ck. 2595 TemplateArgumentListInfo ExplicitArgs; 2596 unsigned CharBits = Context.getIntWidth(Context.CharTy); 2597 bool CharIsUnsigned = Context.CharTy->isUnsignedIntegerType(); 2598 llvm::APSInt Value(CharBits, CharIsUnsigned); 2599 for (unsigned I = 0, N = Literal.getUDSuffixOffset(); I != N; ++I) { 2600 Value = ThisTokBegin[I]; 2601 TemplateArgument Arg(Value, Context.CharTy); 2602 TemplateArgumentLocInfo ArgInfo; 2603 ExplicitArgs.addArgument(TemplateArgumentLoc(Arg, ArgInfo)); 2604 } 2605 return BuildLiteralOperatorCall(R, OpNameInfo, ArrayRef<Expr*>(), 2606 Tok.getLocation(), &ExplicitArgs); 2607 } 2608 2609 llvm_unreachable("unexpected literal operator lookup result"); 2610 } 2611 2612 Expr *Res; 2613 2614 if (Literal.isFloatingLiteral()) { 2615 QualType Ty; 2616 if (Literal.isFloat) 2617 Ty = Context.FloatTy; 2618 else if (!Literal.isLong) 2619 Ty = Context.DoubleTy; 2620 else 2621 Ty = Context.LongDoubleTy; 2622 2623 Res = BuildFloatingLiteral(*this, Literal, Ty, Tok.getLocation()); 2624 2625 if (Ty == Context.DoubleTy) { 2626 if (getLangOpts().SinglePrecisionConstants) { 2627 Res = ImpCastExprToType(Res, Context.FloatTy, CK_FloatingCast).take(); 2628 } else if (getLangOpts().OpenCL && !getOpenCLOptions().cl_khr_fp64) { 2629 Diag(Tok.getLocation(), diag::warn_double_const_requires_fp64); 2630 Res = ImpCastExprToType(Res, Context.FloatTy, CK_FloatingCast).take(); 2631 } 2632 } 2633 } else if (!Literal.isIntegerLiteral()) { 2634 return ExprError(); 2635 } else { 2636 QualType Ty; 2637 2638 // long long is a C99 feature. 2639 if (!getLangOpts().C99 && Literal.isLongLong) 2640 Diag(Tok.getLocation(), 2641 getLangOpts().CPlusPlus0x ? 2642 diag::warn_cxx98_compat_longlong : diag::ext_longlong); 2643 2644 // Get the value in the widest-possible width. 2645 llvm::APInt ResultVal(Context.getTargetInfo().getIntMaxTWidth(), 0); 2646 2647 if (Literal.GetIntegerValue(ResultVal)) { 2648 // If this value didn't fit into uintmax_t, warn and force to ull. 2649 Diag(Tok.getLocation(), diag::warn_integer_too_large); 2650 Ty = Context.UnsignedLongLongTy; 2651 assert(Context.getTypeSize(Ty) == ResultVal.getBitWidth() && 2652 "long long is not intmax_t?"); 2653 } else { 2654 // If this value fits into a ULL, try to figure out what else it fits into 2655 // according to the rules of C99 6.4.4.1p5. 2656 2657 // Octal, Hexadecimal, and integers with a U suffix are allowed to 2658 // be an unsigned int. 2659 bool AllowUnsigned = Literal.isUnsigned || Literal.getRadix() != 10; 2660 2661 // Check from smallest to largest, picking the smallest type we can. 2662 unsigned Width = 0; 2663 if (!Literal.isLong && !Literal.isLongLong) { 2664 // Are int/unsigned possibilities? 2665 unsigned IntSize = Context.getTargetInfo().getIntWidth(); 2666 2667 // Does it fit in a unsigned int? 2668 if (ResultVal.isIntN(IntSize)) { 2669 // Does it fit in a signed int? 2670 if (!Literal.isUnsigned && ResultVal[IntSize-1] == 0) 2671 Ty = Context.IntTy; 2672 else if (AllowUnsigned) 2673 Ty = Context.UnsignedIntTy; 2674 Width = IntSize; 2675 } 2676 } 2677 2678 // Are long/unsigned long possibilities? 2679 if (Ty.isNull() && !Literal.isLongLong) { 2680 unsigned LongSize = Context.getTargetInfo().getLongWidth(); 2681 2682 // Does it fit in a unsigned long? 2683 if (ResultVal.isIntN(LongSize)) { 2684 // Does it fit in a signed long? 2685 if (!Literal.isUnsigned && ResultVal[LongSize-1] == 0) 2686 Ty = Context.LongTy; 2687 else if (AllowUnsigned) 2688 Ty = Context.UnsignedLongTy; 2689 Width = LongSize; 2690 } 2691 } 2692 2693 // Finally, check long long if needed. 2694 if (Ty.isNull()) { 2695 unsigned LongLongSize = Context.getTargetInfo().getLongLongWidth(); 2696 2697 // Does it fit in a unsigned long long? 2698 if (ResultVal.isIntN(LongLongSize)) { 2699 // Does it fit in a signed long long? 2700 // To be compatible with MSVC, hex integer literals ending with the 2701 // LL or i64 suffix are always signed in Microsoft mode. 2702 if (!Literal.isUnsigned && (ResultVal[LongLongSize-1] == 0 || 2703 (getLangOpts().MicrosoftExt && Literal.isLongLong))) 2704 Ty = Context.LongLongTy; 2705 else if (AllowUnsigned) 2706 Ty = Context.UnsignedLongLongTy; 2707 Width = LongLongSize; 2708 } 2709 } 2710 2711 // If we still couldn't decide a type, we probably have something that 2712 // does not fit in a signed long long, but has no U suffix. 2713 if (Ty.isNull()) { 2714 Diag(Tok.getLocation(), diag::warn_integer_too_large_for_signed); 2715 Ty = Context.UnsignedLongLongTy; 2716 Width = Context.getTargetInfo().getLongLongWidth(); 2717 } 2718 2719 if (ResultVal.getBitWidth() != Width) 2720 ResultVal = ResultVal.trunc(Width); 2721 } 2722 Res = IntegerLiteral::Create(Context, ResultVal, Ty, Tok.getLocation()); 2723 } 2724 2725 // If this is an imaginary literal, create the ImaginaryLiteral wrapper. 2726 if (Literal.isImaginary) 2727 Res = new (Context) ImaginaryLiteral(Res, 2728 Context.getComplexType(Res->getType())); 2729 2730 return Owned(Res); 2731} 2732 2733ExprResult Sema::ActOnParenExpr(SourceLocation L, SourceLocation R, Expr *E) { 2734 assert((E != 0) && "ActOnParenExpr() missing expr"); 2735 return Owned(new (Context) ParenExpr(L, R, E)); 2736} 2737 2738static bool CheckVecStepTraitOperandType(Sema &S, QualType T, 2739 SourceLocation Loc, 2740 SourceRange ArgRange) { 2741 // [OpenCL 1.1 6.11.12] "The vec_step built-in function takes a built-in 2742 // scalar or vector data type argument..." 2743 // Every built-in scalar type (OpenCL 1.1 6.1.1) is either an arithmetic 2744 // type (C99 6.2.5p18) or void. 2745 if (!(T->isArithmeticType() || T->isVoidType() || T->isVectorType())) { 2746 S.Diag(Loc, diag::err_vecstep_non_scalar_vector_type) 2747 << T << ArgRange; 2748 return true; 2749 } 2750 2751 assert((T->isVoidType() || !T->isIncompleteType()) && 2752 "Scalar types should always be complete"); 2753 return false; 2754} 2755 2756static bool CheckExtensionTraitOperandType(Sema &S, QualType T, 2757 SourceLocation Loc, 2758 SourceRange ArgRange, 2759 UnaryExprOrTypeTrait TraitKind) { 2760 // C99 6.5.3.4p1: 2761 if (T->isFunctionType()) { 2762 // alignof(function) is allowed as an extension. 2763 if (TraitKind == UETT_SizeOf) 2764 S.Diag(Loc, diag::ext_sizeof_function_type) << ArgRange; 2765 return false; 2766 } 2767 2768 // Allow sizeof(void)/alignof(void) as an extension. 2769 if (T->isVoidType()) { 2770 S.Diag(Loc, diag::ext_sizeof_void_type) << TraitKind << ArgRange; 2771 return false; 2772 } 2773 2774 return true; 2775} 2776 2777static bool CheckObjCTraitOperandConstraints(Sema &S, QualType T, 2778 SourceLocation Loc, 2779 SourceRange ArgRange, 2780 UnaryExprOrTypeTrait TraitKind) { 2781 // Reject sizeof(interface) and sizeof(interface<proto>) in 64-bit mode. 2782 if (S.LangOpts.ObjCNonFragileABI && T->isObjCObjectType()) { 2783 S.Diag(Loc, diag::err_sizeof_nonfragile_interface) 2784 << T << (TraitKind == UETT_SizeOf) 2785 << ArgRange; 2786 return true; 2787 } 2788 2789 return false; 2790} 2791 2792/// \brief Check the constrains on expression operands to unary type expression 2793/// and type traits. 2794/// 2795/// Completes any types necessary and validates the constraints on the operand 2796/// expression. The logic mostly mirrors the type-based overload, but may modify 2797/// the expression as it completes the type for that expression through template 2798/// instantiation, etc. 2799bool Sema::CheckUnaryExprOrTypeTraitOperand(Expr *E, 2800 UnaryExprOrTypeTrait ExprKind) { 2801 QualType ExprTy = E->getType(); 2802 2803 // C++ [expr.sizeof]p2: "When applied to a reference or a reference type, 2804 // the result is the size of the referenced type." 2805 // C++ [expr.alignof]p3: "When alignof is applied to a reference type, the 2806 // result shall be the alignment of the referenced type." 2807 if (const ReferenceType *Ref = ExprTy->getAs<ReferenceType>()) 2808 ExprTy = Ref->getPointeeType(); 2809 2810 if (ExprKind == UETT_VecStep) 2811 return CheckVecStepTraitOperandType(*this, ExprTy, E->getExprLoc(), 2812 E->getSourceRange()); 2813 2814 // Whitelist some types as extensions 2815 if (!CheckExtensionTraitOperandType(*this, ExprTy, E->getExprLoc(), 2816 E->getSourceRange(), ExprKind)) 2817 return false; 2818 2819 if (RequireCompleteExprType(E, 2820 PDiag(diag::err_sizeof_alignof_incomplete_type) 2821 << ExprKind << E->getSourceRange(), 2822 std::make_pair(SourceLocation(), PDiag(0)))) 2823 return true; 2824 2825 // Completeing the expression's type may have changed it. 2826 ExprTy = E->getType(); 2827 if (const ReferenceType *Ref = ExprTy->getAs<ReferenceType>()) 2828 ExprTy = Ref->getPointeeType(); 2829 2830 if (CheckObjCTraitOperandConstraints(*this, ExprTy, E->getExprLoc(), 2831 E->getSourceRange(), ExprKind)) 2832 return true; 2833 2834 if (ExprKind == UETT_SizeOf) { 2835 if (DeclRefExpr *DeclRef = dyn_cast<DeclRefExpr>(E->IgnoreParens())) { 2836 if (ParmVarDecl *PVD = dyn_cast<ParmVarDecl>(DeclRef->getFoundDecl())) { 2837 QualType OType = PVD->getOriginalType(); 2838 QualType Type = PVD->getType(); 2839 if (Type->isPointerType() && OType->isArrayType()) { 2840 Diag(E->getExprLoc(), diag::warn_sizeof_array_param) 2841 << Type << OType; 2842 Diag(PVD->getLocation(), diag::note_declared_at); 2843 } 2844 } 2845 } 2846 } 2847 2848 return false; 2849} 2850 2851/// \brief Check the constraints on operands to unary expression and type 2852/// traits. 2853/// 2854/// This will complete any types necessary, and validate the various constraints 2855/// on those operands. 2856/// 2857/// The UsualUnaryConversions() function is *not* called by this routine. 2858/// C99 6.3.2.1p[2-4] all state: 2859/// Except when it is the operand of the sizeof operator ... 2860/// 2861/// C++ [expr.sizeof]p4 2862/// The lvalue-to-rvalue, array-to-pointer, and function-to-pointer 2863/// standard conversions are not applied to the operand of sizeof. 2864/// 2865/// This policy is followed for all of the unary trait expressions. 2866bool Sema::CheckUnaryExprOrTypeTraitOperand(QualType ExprType, 2867 SourceLocation OpLoc, 2868 SourceRange ExprRange, 2869 UnaryExprOrTypeTrait ExprKind) { 2870 if (ExprType->isDependentType()) 2871 return false; 2872 2873 // C++ [expr.sizeof]p2: "When applied to a reference or a reference type, 2874 // the result is the size of the referenced type." 2875 // C++ [expr.alignof]p3: "When alignof is applied to a reference type, the 2876 // result shall be the alignment of the referenced type." 2877 if (const ReferenceType *Ref = ExprType->getAs<ReferenceType>()) 2878 ExprType = Ref->getPointeeType(); 2879 2880 if (ExprKind == UETT_VecStep) 2881 return CheckVecStepTraitOperandType(*this, ExprType, OpLoc, ExprRange); 2882 2883 // Whitelist some types as extensions 2884 if (!CheckExtensionTraitOperandType(*this, ExprType, OpLoc, ExprRange, 2885 ExprKind)) 2886 return false; 2887 2888 if (RequireCompleteType(OpLoc, ExprType, 2889 PDiag(diag::err_sizeof_alignof_incomplete_type) 2890 << ExprKind << ExprRange)) 2891 return true; 2892 2893 if (CheckObjCTraitOperandConstraints(*this, ExprType, OpLoc, ExprRange, 2894 ExprKind)) 2895 return true; 2896 2897 return false; 2898} 2899 2900static bool CheckAlignOfExpr(Sema &S, Expr *E) { 2901 E = E->IgnoreParens(); 2902 2903 // alignof decl is always ok. 2904 if (isa<DeclRefExpr>(E)) 2905 return false; 2906 2907 // Cannot know anything else if the expression is dependent. 2908 if (E->isTypeDependent()) 2909 return false; 2910 2911 if (E->getBitField()) { 2912 S.Diag(E->getExprLoc(), diag::err_sizeof_alignof_bitfield) 2913 << 1 << E->getSourceRange(); 2914 return true; 2915 } 2916 2917 // Alignment of a field access is always okay, so long as it isn't a 2918 // bit-field. 2919 if (MemberExpr *ME = dyn_cast<MemberExpr>(E)) 2920 if (isa<FieldDecl>(ME->getMemberDecl())) 2921 return false; 2922 2923 return S.CheckUnaryExprOrTypeTraitOperand(E, UETT_AlignOf); 2924} 2925 2926bool Sema::CheckVecStepExpr(Expr *E) { 2927 E = E->IgnoreParens(); 2928 2929 // Cannot know anything else if the expression is dependent. 2930 if (E->isTypeDependent()) 2931 return false; 2932 2933 return CheckUnaryExprOrTypeTraitOperand(E, UETT_VecStep); 2934} 2935 2936/// \brief Build a sizeof or alignof expression given a type operand. 2937ExprResult 2938Sema::CreateUnaryExprOrTypeTraitExpr(TypeSourceInfo *TInfo, 2939 SourceLocation OpLoc, 2940 UnaryExprOrTypeTrait ExprKind, 2941 SourceRange R) { 2942 if (!TInfo) 2943 return ExprError(); 2944 2945 QualType T = TInfo->getType(); 2946 2947 if (!T->isDependentType() && 2948 CheckUnaryExprOrTypeTraitOperand(T, OpLoc, R, ExprKind)) 2949 return ExprError(); 2950 2951 // C99 6.5.3.4p4: the type (an unsigned integer type) is size_t. 2952 return Owned(new (Context) UnaryExprOrTypeTraitExpr(ExprKind, TInfo, 2953 Context.getSizeType(), 2954 OpLoc, R.getEnd())); 2955} 2956 2957/// \brief Build a sizeof or alignof expression given an expression 2958/// operand. 2959ExprResult 2960Sema::CreateUnaryExprOrTypeTraitExpr(Expr *E, SourceLocation OpLoc, 2961 UnaryExprOrTypeTrait ExprKind) { 2962 ExprResult PE = CheckPlaceholderExpr(E); 2963 if (PE.isInvalid()) 2964 return ExprError(); 2965 2966 E = PE.get(); 2967 2968 // Verify that the operand is valid. 2969 bool isInvalid = false; 2970 if (E->isTypeDependent()) { 2971 // Delay type-checking for type-dependent expressions. 2972 } else if (ExprKind == UETT_AlignOf) { 2973 isInvalid = CheckAlignOfExpr(*this, E); 2974 } else if (ExprKind == UETT_VecStep) { 2975 isInvalid = CheckVecStepExpr(E); 2976 } else if (E->getBitField()) { // C99 6.5.3.4p1. 2977 Diag(E->getExprLoc(), diag::err_sizeof_alignof_bitfield) << 0; 2978 isInvalid = true; 2979 } else { 2980 isInvalid = CheckUnaryExprOrTypeTraitOperand(E, UETT_SizeOf); 2981 } 2982 2983 if (isInvalid) 2984 return ExprError(); 2985 2986 if (ExprKind == UETT_SizeOf && E->getType()->isVariableArrayType()) { 2987 PE = TranformToPotentiallyEvaluated(E); 2988 if (PE.isInvalid()) return ExprError(); 2989 E = PE.take(); 2990 } 2991 2992 // C99 6.5.3.4p4: the type (an unsigned integer type) is size_t. 2993 return Owned(new (Context) UnaryExprOrTypeTraitExpr( 2994 ExprKind, E, Context.getSizeType(), OpLoc, 2995 E->getSourceRange().getEnd())); 2996} 2997 2998/// ActOnUnaryExprOrTypeTraitExpr - Handle @c sizeof(type) and @c sizeof @c 2999/// expr and the same for @c alignof and @c __alignof 3000/// Note that the ArgRange is invalid if isType is false. 3001ExprResult 3002Sema::ActOnUnaryExprOrTypeTraitExpr(SourceLocation OpLoc, 3003 UnaryExprOrTypeTrait ExprKind, bool IsType, 3004 void *TyOrEx, const SourceRange &ArgRange) { 3005 // If error parsing type, ignore. 3006 if (TyOrEx == 0) return ExprError(); 3007 3008 if (IsType) { 3009 TypeSourceInfo *TInfo; 3010 (void) GetTypeFromParser(ParsedType::getFromOpaquePtr(TyOrEx), &TInfo); 3011 return CreateUnaryExprOrTypeTraitExpr(TInfo, OpLoc, ExprKind, ArgRange); 3012 } 3013 3014 Expr *ArgEx = (Expr *)TyOrEx; 3015 ExprResult Result = CreateUnaryExprOrTypeTraitExpr(ArgEx, OpLoc, ExprKind); 3016 return move(Result); 3017} 3018 3019static QualType CheckRealImagOperand(Sema &S, ExprResult &V, SourceLocation Loc, 3020 bool IsReal) { 3021 if (V.get()->isTypeDependent()) 3022 return S.Context.DependentTy; 3023 3024 // _Real and _Imag are only l-values for normal l-values. 3025 if (V.get()->getObjectKind() != OK_Ordinary) { 3026 V = S.DefaultLvalueConversion(V.take()); 3027 if (V.isInvalid()) 3028 return QualType(); 3029 } 3030 3031 // These operators return the element type of a complex type. 3032 if (const ComplexType *CT = V.get()->getType()->getAs<ComplexType>()) 3033 return CT->getElementType(); 3034 3035 // Otherwise they pass through real integer and floating point types here. 3036 if (V.get()->getType()->isArithmeticType()) 3037 return V.get()->getType(); 3038 3039 // Test for placeholders. 3040 ExprResult PR = S.CheckPlaceholderExpr(V.get()); 3041 if (PR.isInvalid()) return QualType(); 3042 if (PR.get() != V.get()) { 3043 V = move(PR); 3044 return CheckRealImagOperand(S, V, Loc, IsReal); 3045 } 3046 3047 // Reject anything else. 3048 S.Diag(Loc, diag::err_realimag_invalid_type) << V.get()->getType() 3049 << (IsReal ? "__real" : "__imag"); 3050 return QualType(); 3051} 3052 3053 3054 3055ExprResult 3056Sema::ActOnPostfixUnaryOp(Scope *S, SourceLocation OpLoc, 3057 tok::TokenKind Kind, Expr *Input) { 3058 UnaryOperatorKind Opc; 3059 switch (Kind) { 3060 default: llvm_unreachable("Unknown unary op!"); 3061 case tok::plusplus: Opc = UO_PostInc; break; 3062 case tok::minusminus: Opc = UO_PostDec; break; 3063 } 3064 3065 // Since this might is a postfix expression, get rid of ParenListExprs. 3066 ExprResult Result = MaybeConvertParenListExprToParenExpr(S, Input); 3067 if (Result.isInvalid()) return ExprError(); 3068 Input = Result.take(); 3069 3070 return BuildUnaryOp(S, OpLoc, Opc, Input); 3071} 3072 3073ExprResult 3074Sema::ActOnArraySubscriptExpr(Scope *S, Expr *Base, SourceLocation LLoc, 3075 Expr *Idx, SourceLocation RLoc) { 3076 // Since this might be a postfix expression, get rid of ParenListExprs. 3077 ExprResult Result = MaybeConvertParenListExprToParenExpr(S, Base); 3078 if (Result.isInvalid()) return ExprError(); 3079 Base = Result.take(); 3080 3081 Expr *LHSExp = Base, *RHSExp = Idx; 3082 3083 if (getLangOpts().CPlusPlus && 3084 (LHSExp->isTypeDependent() || RHSExp->isTypeDependent())) { 3085 return Owned(new (Context) ArraySubscriptExpr(LHSExp, RHSExp, 3086 Context.DependentTy, 3087 VK_LValue, OK_Ordinary, 3088 RLoc)); 3089 } 3090 3091 if (getLangOpts().CPlusPlus && 3092 (LHSExp->getType()->isRecordType() || 3093 LHSExp->getType()->isEnumeralType() || 3094 RHSExp->getType()->isRecordType() || 3095 RHSExp->getType()->isEnumeralType()) && 3096 !LHSExp->getType()->isObjCObjectPointerType()) { 3097 return CreateOverloadedArraySubscriptExpr(LLoc, RLoc, Base, Idx); 3098 } 3099 3100 return CreateBuiltinArraySubscriptExpr(Base, LLoc, Idx, RLoc); 3101} 3102 3103 3104ExprResult 3105Sema::CreateBuiltinArraySubscriptExpr(Expr *Base, SourceLocation LLoc, 3106 Expr *Idx, SourceLocation RLoc) { 3107 Expr *LHSExp = Base; 3108 Expr *RHSExp = Idx; 3109 3110 // Perform default conversions. 3111 if (!LHSExp->getType()->getAs<VectorType>()) { 3112 ExprResult Result = DefaultFunctionArrayLvalueConversion(LHSExp); 3113 if (Result.isInvalid()) 3114 return ExprError(); 3115 LHSExp = Result.take(); 3116 } 3117 ExprResult Result = DefaultFunctionArrayLvalueConversion(RHSExp); 3118 if (Result.isInvalid()) 3119 return ExprError(); 3120 RHSExp = Result.take(); 3121 3122 QualType LHSTy = LHSExp->getType(), RHSTy = RHSExp->getType(); 3123 ExprValueKind VK = VK_LValue; 3124 ExprObjectKind OK = OK_Ordinary; 3125 3126 // C99 6.5.2.1p2: the expression e1[e2] is by definition precisely equivalent 3127 // to the expression *((e1)+(e2)). This means the array "Base" may actually be 3128 // in the subscript position. As a result, we need to derive the array base 3129 // and index from the expression types. 3130 Expr *BaseExpr, *IndexExpr; 3131 QualType ResultType; 3132 if (LHSTy->isDependentType() || RHSTy->isDependentType()) { 3133 BaseExpr = LHSExp; 3134 IndexExpr = RHSExp; 3135 ResultType = Context.DependentTy; 3136 } else if (const PointerType *PTy = LHSTy->getAs<PointerType>()) { 3137 BaseExpr = LHSExp; 3138 IndexExpr = RHSExp; 3139 ResultType = PTy->getPointeeType(); 3140 } else if (const ObjCObjectPointerType *PTy = 3141 LHSTy->getAs<ObjCObjectPointerType>()) { 3142 BaseExpr = LHSExp; 3143 IndexExpr = RHSExp; 3144 Result = BuildObjCSubscriptExpression(RLoc, BaseExpr, IndexExpr, 0, 0); 3145 if (!Result.isInvalid()) 3146 return Owned(Result.take()); 3147 ResultType = PTy->getPointeeType(); 3148 } else if (const PointerType *PTy = RHSTy->getAs<PointerType>()) { 3149 // Handle the uncommon case of "123[Ptr]". 3150 BaseExpr = RHSExp; 3151 IndexExpr = LHSExp; 3152 ResultType = PTy->getPointeeType(); 3153 } else if (const ObjCObjectPointerType *PTy = 3154 RHSTy->getAs<ObjCObjectPointerType>()) { 3155 // Handle the uncommon case of "123[Ptr]". 3156 BaseExpr = RHSExp; 3157 IndexExpr = LHSExp; 3158 ResultType = PTy->getPointeeType(); 3159 } else if (const VectorType *VTy = LHSTy->getAs<VectorType>()) { 3160 BaseExpr = LHSExp; // vectors: V[123] 3161 IndexExpr = RHSExp; 3162 VK = LHSExp->getValueKind(); 3163 if (VK != VK_RValue) 3164 OK = OK_VectorComponent; 3165 3166 // FIXME: need to deal with const... 3167 ResultType = VTy->getElementType(); 3168 } else if (LHSTy->isArrayType()) { 3169 // If we see an array that wasn't promoted by 3170 // DefaultFunctionArrayLvalueConversion, it must be an array that 3171 // wasn't promoted because of the C90 rule that doesn't 3172 // allow promoting non-lvalue arrays. Warn, then 3173 // force the promotion here. 3174 Diag(LHSExp->getLocStart(), diag::ext_subscript_non_lvalue) << 3175 LHSExp->getSourceRange(); 3176 LHSExp = ImpCastExprToType(LHSExp, Context.getArrayDecayedType(LHSTy), 3177 CK_ArrayToPointerDecay).take(); 3178 LHSTy = LHSExp->getType(); 3179 3180 BaseExpr = LHSExp; 3181 IndexExpr = RHSExp; 3182 ResultType = LHSTy->getAs<PointerType>()->getPointeeType(); 3183 } else if (RHSTy->isArrayType()) { 3184 // Same as previous, except for 123[f().a] case 3185 Diag(RHSExp->getLocStart(), diag::ext_subscript_non_lvalue) << 3186 RHSExp->getSourceRange(); 3187 RHSExp = ImpCastExprToType(RHSExp, Context.getArrayDecayedType(RHSTy), 3188 CK_ArrayToPointerDecay).take(); 3189 RHSTy = RHSExp->getType(); 3190 3191 BaseExpr = RHSExp; 3192 IndexExpr = LHSExp; 3193 ResultType = RHSTy->getAs<PointerType>()->getPointeeType(); 3194 } else { 3195 return ExprError(Diag(LLoc, diag::err_typecheck_subscript_value) 3196 << LHSExp->getSourceRange() << RHSExp->getSourceRange()); 3197 } 3198 // C99 6.5.2.1p1 3199 if (!IndexExpr->getType()->isIntegerType() && !IndexExpr->isTypeDependent()) 3200 return ExprError(Diag(LLoc, diag::err_typecheck_subscript_not_integer) 3201 << IndexExpr->getSourceRange()); 3202 3203 if ((IndexExpr->getType()->isSpecificBuiltinType(BuiltinType::Char_S) || 3204 IndexExpr->getType()->isSpecificBuiltinType(BuiltinType::Char_U)) 3205 && !IndexExpr->isTypeDependent()) 3206 Diag(LLoc, diag::warn_subscript_is_char) << IndexExpr->getSourceRange(); 3207 3208 // C99 6.5.2.1p1: "shall have type "pointer to *object* type". Similarly, 3209 // C++ [expr.sub]p1: The type "T" shall be a completely-defined object 3210 // type. Note that Functions are not objects, and that (in C99 parlance) 3211 // incomplete types are not object types. 3212 if (ResultType->isFunctionType()) { 3213 Diag(BaseExpr->getLocStart(), diag::err_subscript_function_type) 3214 << ResultType << BaseExpr->getSourceRange(); 3215 return ExprError(); 3216 } 3217 3218 if (ResultType->isVoidType() && !getLangOpts().CPlusPlus) { 3219 // GNU extension: subscripting on pointer to void 3220 Diag(LLoc, diag::ext_gnu_subscript_void_type) 3221 << BaseExpr->getSourceRange(); 3222 3223 // C forbids expressions of unqualified void type from being l-values. 3224 // See IsCForbiddenLValueType. 3225 if (!ResultType.hasQualifiers()) VK = VK_RValue; 3226 } else if (!ResultType->isDependentType() && 3227 RequireCompleteType(LLoc, ResultType, 3228 PDiag(diag::err_subscript_incomplete_type) 3229 << BaseExpr->getSourceRange())) 3230 return ExprError(); 3231 3232 // Diagnose bad cases where we step over interface counts. 3233 if (ResultType->isObjCObjectType() && LangOpts.ObjCNonFragileABI) { 3234 Diag(LLoc, diag::err_subscript_nonfragile_interface) 3235 << ResultType << BaseExpr->getSourceRange(); 3236 return ExprError(); 3237 } 3238 3239 assert(VK == VK_RValue || LangOpts.CPlusPlus || 3240 !ResultType.isCForbiddenLValueType()); 3241 3242 return Owned(new (Context) ArraySubscriptExpr(LHSExp, RHSExp, 3243 ResultType, VK, OK, RLoc)); 3244} 3245 3246ExprResult Sema::BuildCXXDefaultArgExpr(SourceLocation CallLoc, 3247 FunctionDecl *FD, 3248 ParmVarDecl *Param) { 3249 if (Param->hasUnparsedDefaultArg()) { 3250 Diag(CallLoc, 3251 diag::err_use_of_default_argument_to_function_declared_later) << 3252 FD << cast<CXXRecordDecl>(FD->getDeclContext())->getDeclName(); 3253 Diag(UnparsedDefaultArgLocs[Param], 3254 diag::note_default_argument_declared_here); 3255 return ExprError(); 3256 } 3257 3258 if (Param->hasUninstantiatedDefaultArg()) { 3259 Expr *UninstExpr = Param->getUninstantiatedDefaultArg(); 3260 3261 // Instantiate the expression. 3262 MultiLevelTemplateArgumentList ArgList 3263 = getTemplateInstantiationArgs(FD, 0, /*RelativeToPrimary=*/true); 3264 3265 std::pair<const TemplateArgument *, unsigned> Innermost 3266 = ArgList.getInnermost(); 3267 InstantiatingTemplate Inst(*this, CallLoc, Param, Innermost.first, 3268 Innermost.second); 3269 3270 ExprResult Result; 3271 { 3272 // C++ [dcl.fct.default]p5: 3273 // The names in the [default argument] expression are bound, and 3274 // the semantic constraints are checked, at the point where the 3275 // default argument expression appears. 3276 ContextRAII SavedContext(*this, FD); 3277 LocalInstantiationScope Local(*this); 3278 Result = SubstExpr(UninstExpr, ArgList); 3279 } 3280 if (Result.isInvalid()) 3281 return ExprError(); 3282 3283 // Check the expression as an initializer for the parameter. 3284 InitializedEntity Entity 3285 = InitializedEntity::InitializeParameter(Context, Param); 3286 InitializationKind Kind 3287 = InitializationKind::CreateCopy(Param->getLocation(), 3288 /*FIXME:EqualLoc*/UninstExpr->getLocStart()); 3289 Expr *ResultE = Result.takeAs<Expr>(); 3290 3291 InitializationSequence InitSeq(*this, Entity, Kind, &ResultE, 1); 3292 Result = InitSeq.Perform(*this, Entity, Kind, 3293 MultiExprArg(*this, &ResultE, 1)); 3294 if (Result.isInvalid()) 3295 return ExprError(); 3296 3297 // Build the default argument expression. 3298 return Owned(CXXDefaultArgExpr::Create(Context, CallLoc, Param, 3299 Result.takeAs<Expr>())); 3300 } 3301 3302 // If the default expression creates temporaries, we need to 3303 // push them to the current stack of expression temporaries so they'll 3304 // be properly destroyed. 3305 // FIXME: We should really be rebuilding the default argument with new 3306 // bound temporaries; see the comment in PR5810. 3307 // We don't need to do that with block decls, though, because 3308 // blocks in default argument expression can never capture anything. 3309 if (isa<ExprWithCleanups>(Param->getInit())) { 3310 // Set the "needs cleanups" bit regardless of whether there are 3311 // any explicit objects. 3312 ExprNeedsCleanups = true; 3313 3314 // Append all the objects to the cleanup list. Right now, this 3315 // should always be a no-op, because blocks in default argument 3316 // expressions should never be able to capture anything. 3317 assert(!cast<ExprWithCleanups>(Param->getInit())->getNumObjects() && 3318 "default argument expression has capturing blocks?"); 3319 } 3320 3321 // We already type-checked the argument, so we know it works. 3322 // Just mark all of the declarations in this potentially-evaluated expression 3323 // as being "referenced". 3324 MarkDeclarationsReferencedInExpr(Param->getDefaultArg(), 3325 /*SkipLocalVariables=*/true); 3326 return Owned(CXXDefaultArgExpr::Create(Context, CallLoc, Param)); 3327} 3328 3329/// ConvertArgumentsForCall - Converts the arguments specified in 3330/// Args/NumArgs to the parameter types of the function FDecl with 3331/// function prototype Proto. Call is the call expression itself, and 3332/// Fn is the function expression. For a C++ member function, this 3333/// routine does not attempt to convert the object argument. Returns 3334/// true if the call is ill-formed. 3335bool 3336Sema::ConvertArgumentsForCall(CallExpr *Call, Expr *Fn, 3337 FunctionDecl *FDecl, 3338 const FunctionProtoType *Proto, 3339 Expr **Args, unsigned NumArgs, 3340 SourceLocation RParenLoc, 3341 bool IsExecConfig) { 3342 // Bail out early if calling a builtin with custom typechecking. 3343 // We don't need to do this in the 3344 if (FDecl) 3345 if (unsigned ID = FDecl->getBuiltinID()) 3346 if (Context.BuiltinInfo.hasCustomTypechecking(ID)) 3347 return false; 3348 3349 // C99 6.5.2.2p7 - the arguments are implicitly converted, as if by 3350 // assignment, to the types of the corresponding parameter, ... 3351 unsigned NumArgsInProto = Proto->getNumArgs(); 3352 bool Invalid = false; 3353 unsigned MinArgs = FDecl ? FDecl->getMinRequiredArguments() : NumArgsInProto; 3354 unsigned FnKind = Fn->getType()->isBlockPointerType() 3355 ? 1 /* block */ 3356 : (IsExecConfig ? 3 /* kernel function (exec config) */ 3357 : 0 /* function */); 3358 3359 // If too few arguments are available (and we don't have default 3360 // arguments for the remaining parameters), don't make the call. 3361 if (NumArgs < NumArgsInProto) { 3362 if (NumArgs < MinArgs) { 3363 Diag(RParenLoc, MinArgs == NumArgsInProto 3364 ? diag::err_typecheck_call_too_few_args 3365 : diag::err_typecheck_call_too_few_args_at_least) 3366 << FnKind 3367 << MinArgs << NumArgs << Fn->getSourceRange(); 3368 3369 // Emit the location of the prototype. 3370 if (FDecl && !FDecl->getBuiltinID() && !IsExecConfig) 3371 Diag(FDecl->getLocStart(), diag::note_callee_decl) 3372 << FDecl; 3373 3374 return true; 3375 } 3376 Call->setNumArgs(Context, NumArgsInProto); 3377 } 3378 3379 // If too many are passed and not variadic, error on the extras and drop 3380 // them. 3381 if (NumArgs > NumArgsInProto) { 3382 if (!Proto->isVariadic()) { 3383 Diag(Args[NumArgsInProto]->getLocStart(), 3384 MinArgs == NumArgsInProto 3385 ? diag::err_typecheck_call_too_many_args 3386 : diag::err_typecheck_call_too_many_args_at_most) 3387 << FnKind 3388 << NumArgsInProto << NumArgs << Fn->getSourceRange() 3389 << SourceRange(Args[NumArgsInProto]->getLocStart(), 3390 Args[NumArgs-1]->getLocEnd()); 3391 3392 // Emit the location of the prototype. 3393 if (FDecl && !FDecl->getBuiltinID() && !IsExecConfig) 3394 Diag(FDecl->getLocStart(), diag::note_callee_decl) 3395 << FDecl; 3396 3397 // This deletes the extra arguments. 3398 Call->setNumArgs(Context, NumArgsInProto); 3399 return true; 3400 } 3401 } 3402 SmallVector<Expr *, 8> AllArgs; 3403 VariadicCallType CallType = 3404 Proto->isVariadic() ? VariadicFunction : VariadicDoesNotApply; 3405 if (Fn->getType()->isBlockPointerType()) 3406 CallType = VariadicBlock; // Block 3407 else if (isa<MemberExpr>(Fn)) 3408 CallType = VariadicMethod; 3409 Invalid = GatherArgumentsForCall(Call->getLocStart(), FDecl, 3410 Proto, 0, Args, NumArgs, AllArgs, CallType); 3411 if (Invalid) 3412 return true; 3413 unsigned TotalNumArgs = AllArgs.size(); 3414 for (unsigned i = 0; i < TotalNumArgs; ++i) 3415 Call->setArg(i, AllArgs[i]); 3416 3417 return false; 3418} 3419 3420bool Sema::GatherArgumentsForCall(SourceLocation CallLoc, 3421 FunctionDecl *FDecl, 3422 const FunctionProtoType *Proto, 3423 unsigned FirstProtoArg, 3424 Expr **Args, unsigned NumArgs, 3425 SmallVector<Expr *, 8> &AllArgs, 3426 VariadicCallType CallType, 3427 bool AllowExplicit) { 3428 unsigned NumArgsInProto = Proto->getNumArgs(); 3429 unsigned NumArgsToCheck = NumArgs; 3430 bool Invalid = false; 3431 if (NumArgs != NumArgsInProto) 3432 // Use default arguments for missing arguments 3433 NumArgsToCheck = NumArgsInProto; 3434 unsigned ArgIx = 0; 3435 // Continue to check argument types (even if we have too few/many args). 3436 for (unsigned i = FirstProtoArg; i != NumArgsToCheck; i++) { 3437 QualType ProtoArgType = Proto->getArgType(i); 3438 3439 Expr *Arg; 3440 ParmVarDecl *Param; 3441 if (ArgIx < NumArgs) { 3442 Arg = Args[ArgIx++]; 3443 3444 if (RequireCompleteType(Arg->getLocStart(), 3445 ProtoArgType, 3446 PDiag(diag::err_call_incomplete_argument) 3447 << Arg->getSourceRange())) 3448 return true; 3449 3450 // Pass the argument 3451 Param = 0; 3452 if (FDecl && i < FDecl->getNumParams()) 3453 Param = FDecl->getParamDecl(i); 3454 3455 // Strip the unbridged-cast placeholder expression off, if applicable. 3456 if (Arg->getType() == Context.ARCUnbridgedCastTy && 3457 FDecl && FDecl->hasAttr<CFAuditedTransferAttr>() && 3458 (!Param || !Param->hasAttr<CFConsumedAttr>())) 3459 Arg = stripARCUnbridgedCast(Arg); 3460 3461 InitializedEntity Entity = 3462 Param? InitializedEntity::InitializeParameter(Context, Param) 3463 : InitializedEntity::InitializeParameter(Context, ProtoArgType, 3464 Proto->isArgConsumed(i)); 3465 ExprResult ArgE = PerformCopyInitialization(Entity, 3466 SourceLocation(), 3467 Owned(Arg), 3468 /*TopLevelOfInitList=*/false, 3469 AllowExplicit); 3470 if (ArgE.isInvalid()) 3471 return true; 3472 3473 Arg = ArgE.takeAs<Expr>(); 3474 } else { 3475 Param = FDecl->getParamDecl(i); 3476 3477 ExprResult ArgExpr = 3478 BuildCXXDefaultArgExpr(CallLoc, FDecl, Param); 3479 if (ArgExpr.isInvalid()) 3480 return true; 3481 3482 Arg = ArgExpr.takeAs<Expr>(); 3483 } 3484 3485 // Check for array bounds violations for each argument to the call. This 3486 // check only triggers warnings when the argument isn't a more complex Expr 3487 // with its own checking, such as a BinaryOperator. 3488 CheckArrayAccess(Arg); 3489 3490 // Check for violations of C99 static array rules (C99 6.7.5.3p7). 3491 CheckStaticArrayArgument(CallLoc, Param, Arg); 3492 3493 AllArgs.push_back(Arg); 3494 } 3495 3496 // If this is a variadic call, handle args passed through "...". 3497 if (CallType != VariadicDoesNotApply) { 3498 3499 // Assume that extern "C" functions with variadic arguments that 3500 // return __unknown_anytype aren't *really* variadic. 3501 if (Proto->getResultType() == Context.UnknownAnyTy && 3502 FDecl && FDecl->isExternC()) { 3503 for (unsigned i = ArgIx; i != NumArgs; ++i) { 3504 ExprResult arg; 3505 if (isa<ExplicitCastExpr>(Args[i]->IgnoreParens())) 3506 arg = DefaultFunctionArrayLvalueConversion(Args[i]); 3507 else 3508 arg = DefaultVariadicArgumentPromotion(Args[i], CallType, FDecl); 3509 Invalid |= arg.isInvalid(); 3510 AllArgs.push_back(arg.take()); 3511 } 3512 3513 // Otherwise do argument promotion, (C99 6.5.2.2p7). 3514 } else { 3515 for (unsigned i = ArgIx; i != NumArgs; ++i) { 3516 ExprResult Arg = DefaultVariadicArgumentPromotion(Args[i], CallType, 3517 FDecl); 3518 Invalid |= Arg.isInvalid(); 3519 AllArgs.push_back(Arg.take()); 3520 } 3521 } 3522 3523 // Check for array bounds violations. 3524 for (unsigned i = ArgIx; i != NumArgs; ++i) 3525 CheckArrayAccess(Args[i]); 3526 } 3527 return Invalid; 3528} 3529 3530static void DiagnoseCalleeStaticArrayParam(Sema &S, ParmVarDecl *PVD) { 3531 TypeLoc TL = PVD->getTypeSourceInfo()->getTypeLoc(); 3532 if (ArrayTypeLoc *ATL = dyn_cast<ArrayTypeLoc>(&TL)) 3533 S.Diag(PVD->getLocation(), diag::note_callee_static_array) 3534 << ATL->getLocalSourceRange(); 3535} 3536 3537/// CheckStaticArrayArgument - If the given argument corresponds to a static 3538/// array parameter, check that it is non-null, and that if it is formed by 3539/// array-to-pointer decay, the underlying array is sufficiently large. 3540/// 3541/// C99 6.7.5.3p7: If the keyword static also appears within the [ and ] of the 3542/// array type derivation, then for each call to the function, the value of the 3543/// corresponding actual argument shall provide access to the first element of 3544/// an array with at least as many elements as specified by the size expression. 3545void 3546Sema::CheckStaticArrayArgument(SourceLocation CallLoc, 3547 ParmVarDecl *Param, 3548 const Expr *ArgExpr) { 3549 // Static array parameters are not supported in C++. 3550 if (!Param || getLangOpts().CPlusPlus) 3551 return; 3552 3553 QualType OrigTy = Param->getOriginalType(); 3554 3555 const ArrayType *AT = Context.getAsArrayType(OrigTy); 3556 if (!AT || AT->getSizeModifier() != ArrayType::Static) 3557 return; 3558 3559 if (ArgExpr->isNullPointerConstant(Context, 3560 Expr::NPC_NeverValueDependent)) { 3561 Diag(CallLoc, diag::warn_null_arg) << ArgExpr->getSourceRange(); 3562 DiagnoseCalleeStaticArrayParam(*this, Param); 3563 return; 3564 } 3565 3566 const ConstantArrayType *CAT = dyn_cast<ConstantArrayType>(AT); 3567 if (!CAT) 3568 return; 3569 3570 const ConstantArrayType *ArgCAT = 3571 Context.getAsConstantArrayType(ArgExpr->IgnoreParenImpCasts()->getType()); 3572 if (!ArgCAT) 3573 return; 3574 3575 if (ArgCAT->getSize().ult(CAT->getSize())) { 3576 Diag(CallLoc, diag::warn_static_array_too_small) 3577 << ArgExpr->getSourceRange() 3578 << (unsigned) ArgCAT->getSize().getZExtValue() 3579 << (unsigned) CAT->getSize().getZExtValue(); 3580 DiagnoseCalleeStaticArrayParam(*this, Param); 3581 } 3582} 3583 3584/// Given a function expression of unknown-any type, try to rebuild it 3585/// to have a function type. 3586static ExprResult rebuildUnknownAnyFunction(Sema &S, Expr *fn); 3587 3588/// ActOnCallExpr - Handle a call to Fn with the specified array of arguments. 3589/// This provides the location of the left/right parens and a list of comma 3590/// locations. 3591ExprResult 3592Sema::ActOnCallExpr(Scope *S, Expr *Fn, SourceLocation LParenLoc, 3593 MultiExprArg ArgExprs, SourceLocation RParenLoc, 3594 Expr *ExecConfig, bool IsExecConfig) { 3595 unsigned NumArgs = ArgExprs.size(); 3596 3597 // Since this might be a postfix expression, get rid of ParenListExprs. 3598 ExprResult Result = MaybeConvertParenListExprToParenExpr(S, Fn); 3599 if (Result.isInvalid()) return ExprError(); 3600 Fn = Result.take(); 3601 3602 Expr **Args = ArgExprs.release(); 3603 3604 if (getLangOpts().CPlusPlus) { 3605 // If this is a pseudo-destructor expression, build the call immediately. 3606 if (isa<CXXPseudoDestructorExpr>(Fn)) { 3607 if (NumArgs > 0) { 3608 // Pseudo-destructor calls should not have any arguments. 3609 Diag(Fn->getLocStart(), diag::err_pseudo_dtor_call_with_args) 3610 << FixItHint::CreateRemoval( 3611 SourceRange(Args[0]->getLocStart(), 3612 Args[NumArgs-1]->getLocEnd())); 3613 } 3614 3615 return Owned(new (Context) CallExpr(Context, Fn, 0, 0, Context.VoidTy, 3616 VK_RValue, RParenLoc)); 3617 } 3618 3619 // Determine whether this is a dependent call inside a C++ template, 3620 // in which case we won't do any semantic analysis now. 3621 // FIXME: Will need to cache the results of name lookup (including ADL) in 3622 // Fn. 3623 bool Dependent = false; 3624 if (Fn->isTypeDependent()) 3625 Dependent = true; 3626 else if (Expr::hasAnyTypeDependentArguments( 3627 llvm::makeArrayRef(Args, NumArgs))) 3628 Dependent = true; 3629 3630 if (Dependent) { 3631 if (ExecConfig) { 3632 return Owned(new (Context) CUDAKernelCallExpr( 3633 Context, Fn, cast<CallExpr>(ExecConfig), Args, NumArgs, 3634 Context.DependentTy, VK_RValue, RParenLoc)); 3635 } else { 3636 return Owned(new (Context) CallExpr(Context, Fn, Args, NumArgs, 3637 Context.DependentTy, VK_RValue, 3638 RParenLoc)); 3639 } 3640 } 3641 3642 // Determine whether this is a call to an object (C++ [over.call.object]). 3643 if (Fn->getType()->isRecordType()) 3644 return Owned(BuildCallToObjectOfClassType(S, Fn, LParenLoc, Args, NumArgs, 3645 RParenLoc)); 3646 3647 if (Fn->getType() == Context.UnknownAnyTy) { 3648 ExprResult result = rebuildUnknownAnyFunction(*this, Fn); 3649 if (result.isInvalid()) return ExprError(); 3650 Fn = result.take(); 3651 } 3652 3653 if (Fn->getType() == Context.BoundMemberTy) { 3654 return BuildCallToMemberFunction(S, Fn, LParenLoc, Args, NumArgs, 3655 RParenLoc); 3656 } 3657 } 3658 3659 // Check for overloaded calls. This can happen even in C due to extensions. 3660 if (Fn->getType() == Context.OverloadTy) { 3661 OverloadExpr::FindResult find = OverloadExpr::find(Fn); 3662 3663 // We aren't supposed to apply this logic for if there's an '&' involved. 3664 if (!find.HasFormOfMemberPointer) { 3665 OverloadExpr *ovl = find.Expression; 3666 if (isa<UnresolvedLookupExpr>(ovl)) { 3667 UnresolvedLookupExpr *ULE = cast<UnresolvedLookupExpr>(ovl); 3668 return BuildOverloadedCallExpr(S, Fn, ULE, LParenLoc, Args, NumArgs, 3669 RParenLoc, ExecConfig); 3670 } else { 3671 return BuildCallToMemberFunction(S, Fn, LParenLoc, Args, NumArgs, 3672 RParenLoc); 3673 } 3674 } 3675 } 3676 3677 // If we're directly calling a function, get the appropriate declaration. 3678 if (Fn->getType() == Context.UnknownAnyTy) { 3679 ExprResult result = rebuildUnknownAnyFunction(*this, Fn); 3680 if (result.isInvalid()) return ExprError(); 3681 Fn = result.take(); 3682 } 3683 3684 Expr *NakedFn = Fn->IgnoreParens(); 3685 3686 NamedDecl *NDecl = 0; 3687 if (UnaryOperator *UnOp = dyn_cast<UnaryOperator>(NakedFn)) 3688 if (UnOp->getOpcode() == UO_AddrOf) 3689 NakedFn = UnOp->getSubExpr()->IgnoreParens(); 3690 3691 if (isa<DeclRefExpr>(NakedFn)) 3692 NDecl = cast<DeclRefExpr>(NakedFn)->getDecl(); 3693 else if (isa<MemberExpr>(NakedFn)) 3694 NDecl = cast<MemberExpr>(NakedFn)->getMemberDecl(); 3695 3696 return BuildResolvedCallExpr(Fn, NDecl, LParenLoc, Args, NumArgs, RParenLoc, 3697 ExecConfig, IsExecConfig); 3698} 3699 3700ExprResult 3701Sema::ActOnCUDAExecConfigExpr(Scope *S, SourceLocation LLLLoc, 3702 MultiExprArg ExecConfig, SourceLocation GGGLoc) { 3703 FunctionDecl *ConfigDecl = Context.getcudaConfigureCallDecl(); 3704 if (!ConfigDecl) 3705 return ExprError(Diag(LLLLoc, diag::err_undeclared_var_use) 3706 << "cudaConfigureCall"); 3707 QualType ConfigQTy = ConfigDecl->getType(); 3708 3709 DeclRefExpr *ConfigDR = new (Context) DeclRefExpr( 3710 ConfigDecl, false, ConfigQTy, VK_LValue, LLLLoc); 3711 MarkFunctionReferenced(LLLLoc, ConfigDecl); 3712 3713 return ActOnCallExpr(S, ConfigDR, LLLLoc, ExecConfig, GGGLoc, 0, 3714 /*IsExecConfig=*/true); 3715} 3716 3717/// ActOnAsTypeExpr - create a new asType (bitcast) from the arguments. 3718/// 3719/// __builtin_astype( value, dst type ) 3720/// 3721ExprResult Sema::ActOnAsTypeExpr(Expr *E, ParsedType ParsedDestTy, 3722 SourceLocation BuiltinLoc, 3723 SourceLocation RParenLoc) { 3724 ExprValueKind VK = VK_RValue; 3725 ExprObjectKind OK = OK_Ordinary; 3726 QualType DstTy = GetTypeFromParser(ParsedDestTy); 3727 QualType SrcTy = E->getType(); 3728 if (Context.getTypeSize(DstTy) != Context.getTypeSize(SrcTy)) 3729 return ExprError(Diag(BuiltinLoc, 3730 diag::err_invalid_astype_of_different_size) 3731 << DstTy 3732 << SrcTy 3733 << E->getSourceRange()); 3734 return Owned(new (Context) AsTypeExpr(E, DstTy, VK, OK, BuiltinLoc, 3735 RParenLoc)); 3736} 3737 3738/// BuildResolvedCallExpr - Build a call to a resolved expression, 3739/// i.e. an expression not of \p OverloadTy. The expression should 3740/// unary-convert to an expression of function-pointer or 3741/// block-pointer type. 3742/// 3743/// \param NDecl the declaration being called, if available 3744ExprResult 3745Sema::BuildResolvedCallExpr(Expr *Fn, NamedDecl *NDecl, 3746 SourceLocation LParenLoc, 3747 Expr **Args, unsigned NumArgs, 3748 SourceLocation RParenLoc, 3749 Expr *Config, bool IsExecConfig) { 3750 FunctionDecl *FDecl = dyn_cast_or_null<FunctionDecl>(NDecl); 3751 3752 // Promote the function operand. 3753 ExprResult Result = UsualUnaryConversions(Fn); 3754 if (Result.isInvalid()) 3755 return ExprError(); 3756 Fn = Result.take(); 3757 3758 // Make the call expr early, before semantic checks. This guarantees cleanup 3759 // of arguments and function on error. 3760 CallExpr *TheCall; 3761 if (Config) { 3762 TheCall = new (Context) CUDAKernelCallExpr(Context, Fn, 3763 cast<CallExpr>(Config), 3764 Args, NumArgs, 3765 Context.BoolTy, 3766 VK_RValue, 3767 RParenLoc); 3768 } else { 3769 TheCall = new (Context) CallExpr(Context, Fn, 3770 Args, NumArgs, 3771 Context.BoolTy, 3772 VK_RValue, 3773 RParenLoc); 3774 } 3775 3776 unsigned BuiltinID = (FDecl ? FDecl->getBuiltinID() : 0); 3777 3778 // Bail out early if calling a builtin with custom typechecking. 3779 if (BuiltinID && Context.BuiltinInfo.hasCustomTypechecking(BuiltinID)) 3780 return CheckBuiltinFunctionCall(BuiltinID, TheCall); 3781 3782 retry: 3783 const FunctionType *FuncT; 3784 if (const PointerType *PT = Fn->getType()->getAs<PointerType>()) { 3785 // C99 6.5.2.2p1 - "The expression that denotes the called function shall 3786 // have type pointer to function". 3787 FuncT = PT->getPointeeType()->getAs<FunctionType>(); 3788 if (FuncT == 0) 3789 return ExprError(Diag(LParenLoc, diag::err_typecheck_call_not_function) 3790 << Fn->getType() << Fn->getSourceRange()); 3791 } else if (const BlockPointerType *BPT = 3792 Fn->getType()->getAs<BlockPointerType>()) { 3793 FuncT = BPT->getPointeeType()->castAs<FunctionType>(); 3794 } else { 3795 // Handle calls to expressions of unknown-any type. 3796 if (Fn->getType() == Context.UnknownAnyTy) { 3797 ExprResult rewrite = rebuildUnknownAnyFunction(*this, Fn); 3798 if (rewrite.isInvalid()) return ExprError(); 3799 Fn = rewrite.take(); 3800 TheCall->setCallee(Fn); 3801 goto retry; 3802 } 3803 3804 return ExprError(Diag(LParenLoc, diag::err_typecheck_call_not_function) 3805 << Fn->getType() << Fn->getSourceRange()); 3806 } 3807 3808 if (getLangOpts().CUDA) { 3809 if (Config) { 3810 // CUDA: Kernel calls must be to global functions 3811 if (FDecl && !FDecl->hasAttr<CUDAGlobalAttr>()) 3812 return ExprError(Diag(LParenLoc,diag::err_kern_call_not_global_function) 3813 << FDecl->getName() << Fn->getSourceRange()); 3814 3815 // CUDA: Kernel function must have 'void' return type 3816 if (!FuncT->getResultType()->isVoidType()) 3817 return ExprError(Diag(LParenLoc, diag::err_kern_type_not_void_return) 3818 << Fn->getType() << Fn->getSourceRange()); 3819 } else { 3820 // CUDA: Calls to global functions must be configured 3821 if (FDecl && FDecl->hasAttr<CUDAGlobalAttr>()) 3822 return ExprError(Diag(LParenLoc, diag::err_global_call_not_config) 3823 << FDecl->getName() << Fn->getSourceRange()); 3824 } 3825 } 3826 3827 // Check for a valid return type 3828 if (CheckCallReturnType(FuncT->getResultType(), 3829 Fn->getLocStart(), TheCall, 3830 FDecl)) 3831 return ExprError(); 3832 3833 // We know the result type of the call, set it. 3834 TheCall->setType(FuncT->getCallResultType(Context)); 3835 TheCall->setValueKind(Expr::getValueKindForType(FuncT->getResultType())); 3836 3837 if (const FunctionProtoType *Proto = dyn_cast<FunctionProtoType>(FuncT)) { 3838 if (ConvertArgumentsForCall(TheCall, Fn, FDecl, Proto, Args, NumArgs, 3839 RParenLoc, IsExecConfig)) 3840 return ExprError(); 3841 } else { 3842 assert(isa<FunctionNoProtoType>(FuncT) && "Unknown FunctionType!"); 3843 3844 if (FDecl) { 3845 // Check if we have too few/too many template arguments, based 3846 // on our knowledge of the function definition. 3847 const FunctionDecl *Def = 0; 3848 if (FDecl->hasBody(Def) && NumArgs != Def->param_size()) { 3849 const FunctionProtoType *Proto 3850 = Def->getType()->getAs<FunctionProtoType>(); 3851 if (!Proto || !(Proto->isVariadic() && NumArgs >= Def->param_size())) 3852 Diag(RParenLoc, diag::warn_call_wrong_number_of_arguments) 3853 << (NumArgs > Def->param_size()) << FDecl << Fn->getSourceRange(); 3854 } 3855 3856 // If the function we're calling isn't a function prototype, but we have 3857 // a function prototype from a prior declaratiom, use that prototype. 3858 if (!FDecl->hasPrototype()) 3859 Proto = FDecl->getType()->getAs<FunctionProtoType>(); 3860 } 3861 3862 // Promote the arguments (C99 6.5.2.2p6). 3863 for (unsigned i = 0; i != NumArgs; i++) { 3864 Expr *Arg = Args[i]; 3865 3866 if (Proto && i < Proto->getNumArgs()) { 3867 InitializedEntity Entity 3868 = InitializedEntity::InitializeParameter(Context, 3869 Proto->getArgType(i), 3870 Proto->isArgConsumed(i)); 3871 ExprResult ArgE = PerformCopyInitialization(Entity, 3872 SourceLocation(), 3873 Owned(Arg)); 3874 if (ArgE.isInvalid()) 3875 return true; 3876 3877 Arg = ArgE.takeAs<Expr>(); 3878 3879 } else { 3880 ExprResult ArgE = DefaultArgumentPromotion(Arg); 3881 3882 if (ArgE.isInvalid()) 3883 return true; 3884 3885 Arg = ArgE.takeAs<Expr>(); 3886 } 3887 3888 if (RequireCompleteType(Arg->getLocStart(), 3889 Arg->getType(), 3890 PDiag(diag::err_call_incomplete_argument) 3891 << Arg->getSourceRange())) 3892 return ExprError(); 3893 3894 TheCall->setArg(i, Arg); 3895 } 3896 } 3897 3898 if (CXXMethodDecl *Method = dyn_cast_or_null<CXXMethodDecl>(FDecl)) 3899 if (!Method->isStatic()) 3900 return ExprError(Diag(LParenLoc, diag::err_member_call_without_object) 3901 << Fn->getSourceRange()); 3902 3903 // Check for sentinels 3904 if (NDecl) 3905 DiagnoseSentinelCalls(NDecl, LParenLoc, Args, NumArgs); 3906 3907 // Do special checking on direct calls to functions. 3908 if (FDecl) { 3909 if (CheckFunctionCall(FDecl, TheCall)) 3910 return ExprError(); 3911 3912 if (BuiltinID) 3913 return CheckBuiltinFunctionCall(BuiltinID, TheCall); 3914 } else if (NDecl) { 3915 if (CheckBlockCall(NDecl, TheCall)) 3916 return ExprError(); 3917 } 3918 3919 return MaybeBindToTemporary(TheCall); 3920} 3921 3922ExprResult 3923Sema::ActOnCompoundLiteral(SourceLocation LParenLoc, ParsedType Ty, 3924 SourceLocation RParenLoc, Expr *InitExpr) { 3925 assert((Ty != 0) && "ActOnCompoundLiteral(): missing type"); 3926 // FIXME: put back this assert when initializers are worked out. 3927 //assert((InitExpr != 0) && "ActOnCompoundLiteral(): missing expression"); 3928 3929 TypeSourceInfo *TInfo; 3930 QualType literalType = GetTypeFromParser(Ty, &TInfo); 3931 if (!TInfo) 3932 TInfo = Context.getTrivialTypeSourceInfo(literalType); 3933 3934 return BuildCompoundLiteralExpr(LParenLoc, TInfo, RParenLoc, InitExpr); 3935} 3936 3937ExprResult 3938Sema::BuildCompoundLiteralExpr(SourceLocation LParenLoc, TypeSourceInfo *TInfo, 3939 SourceLocation RParenLoc, Expr *LiteralExpr) { 3940 QualType literalType = TInfo->getType(); 3941 3942 if (literalType->isArrayType()) { 3943 if (RequireCompleteType(LParenLoc, Context.getBaseElementType(literalType), 3944 PDiag(diag::err_illegal_decl_array_incomplete_type) 3945 << SourceRange(LParenLoc, 3946 LiteralExpr->getSourceRange().getEnd()))) 3947 return ExprError(); 3948 if (literalType->isVariableArrayType()) 3949 return ExprError(Diag(LParenLoc, diag::err_variable_object_no_init) 3950 << SourceRange(LParenLoc, LiteralExpr->getSourceRange().getEnd())); 3951 } else if (!literalType->isDependentType() && 3952 RequireCompleteType(LParenLoc, literalType, 3953 PDiag(diag::err_typecheck_decl_incomplete_type) 3954 << SourceRange(LParenLoc, 3955 LiteralExpr->getSourceRange().getEnd()))) 3956 return ExprError(); 3957 3958 InitializedEntity Entity 3959 = InitializedEntity::InitializeTemporary(literalType); 3960 InitializationKind Kind 3961 = InitializationKind::CreateCStyleCast(LParenLoc, 3962 SourceRange(LParenLoc, RParenLoc), 3963 /*InitList=*/true); 3964 InitializationSequence InitSeq(*this, Entity, Kind, &LiteralExpr, 1); 3965 ExprResult Result = InitSeq.Perform(*this, Entity, Kind, 3966 MultiExprArg(*this, &LiteralExpr, 1), 3967 &literalType); 3968 if (Result.isInvalid()) 3969 return ExprError(); 3970 LiteralExpr = Result.get(); 3971 3972 bool isFileScope = getCurFunctionOrMethodDecl() == 0; 3973 if (isFileScope) { // 6.5.2.5p3 3974 if (CheckForConstantInitializer(LiteralExpr, literalType)) 3975 return ExprError(); 3976 } 3977 3978 // In C, compound literals are l-values for some reason. 3979 ExprValueKind VK = getLangOpts().CPlusPlus ? VK_RValue : VK_LValue; 3980 3981 return MaybeBindToTemporary( 3982 new (Context) CompoundLiteralExpr(LParenLoc, TInfo, literalType, 3983 VK, LiteralExpr, isFileScope)); 3984} 3985 3986ExprResult 3987Sema::ActOnInitList(SourceLocation LBraceLoc, MultiExprArg InitArgList, 3988 SourceLocation RBraceLoc) { 3989 unsigned NumInit = InitArgList.size(); 3990 Expr **InitList = InitArgList.release(); 3991 3992 // Immediately handle non-overload placeholders. Overloads can be 3993 // resolved contextually, but everything else here can't. 3994 for (unsigned I = 0; I != NumInit; ++I) { 3995 if (InitList[I]->getType()->isNonOverloadPlaceholderType()) { 3996 ExprResult result = CheckPlaceholderExpr(InitList[I]); 3997 3998 // Ignore failures; dropping the entire initializer list because 3999 // of one failure would be terrible for indexing/etc. 4000 if (result.isInvalid()) continue; 4001 4002 InitList[I] = result.take(); 4003 } 4004 } 4005 4006 // Semantic analysis for initializers is done by ActOnDeclarator() and 4007 // CheckInitializer() - it requires knowledge of the object being intialized. 4008 4009 InitListExpr *E = new (Context) InitListExpr(Context, LBraceLoc, InitList, 4010 NumInit, RBraceLoc); 4011 E->setType(Context.VoidTy); // FIXME: just a place holder for now. 4012 return Owned(E); 4013} 4014 4015/// Do an explicit extend of the given block pointer if we're in ARC. 4016static void maybeExtendBlockObject(Sema &S, ExprResult &E) { 4017 assert(E.get()->getType()->isBlockPointerType()); 4018 assert(E.get()->isRValue()); 4019 4020 // Only do this in an r-value context. 4021 if (!S.getLangOpts().ObjCAutoRefCount) return; 4022 4023 E = ImplicitCastExpr::Create(S.Context, E.get()->getType(), 4024 CK_ARCExtendBlockObject, E.get(), 4025 /*base path*/ 0, VK_RValue); 4026 S.ExprNeedsCleanups = true; 4027} 4028 4029/// Prepare a conversion of the given expression to an ObjC object 4030/// pointer type. 4031CastKind Sema::PrepareCastToObjCObjectPointer(ExprResult &E) { 4032 QualType type = E.get()->getType(); 4033 if (type->isObjCObjectPointerType()) { 4034 return CK_BitCast; 4035 } else if (type->isBlockPointerType()) { 4036 maybeExtendBlockObject(*this, E); 4037 return CK_BlockPointerToObjCPointerCast; 4038 } else { 4039 assert(type->isPointerType()); 4040 return CK_CPointerToObjCPointerCast; 4041 } 4042} 4043 4044/// Prepares for a scalar cast, performing all the necessary stages 4045/// except the final cast and returning the kind required. 4046CastKind Sema::PrepareScalarCast(ExprResult &Src, QualType DestTy) { 4047 // Both Src and Dest are scalar types, i.e. arithmetic or pointer. 4048 // Also, callers should have filtered out the invalid cases with 4049 // pointers. Everything else should be possible. 4050 4051 QualType SrcTy = Src.get()->getType(); 4052 if (const AtomicType *SrcAtomicTy = SrcTy->getAs<AtomicType>()) 4053 SrcTy = SrcAtomicTy->getValueType(); 4054 if (const AtomicType *DestAtomicTy = DestTy->getAs<AtomicType>()) 4055 DestTy = DestAtomicTy->getValueType(); 4056 4057 if (Context.hasSameUnqualifiedType(SrcTy, DestTy)) 4058 return CK_NoOp; 4059 4060 switch (Type::ScalarTypeKind SrcKind = SrcTy->getScalarTypeKind()) { 4061 case Type::STK_MemberPointer: 4062 llvm_unreachable("member pointer type in C"); 4063 4064 case Type::STK_CPointer: 4065 case Type::STK_BlockPointer: 4066 case Type::STK_ObjCObjectPointer: 4067 switch (DestTy->getScalarTypeKind()) { 4068 case Type::STK_CPointer: 4069 return CK_BitCast; 4070 case Type::STK_BlockPointer: 4071 return (SrcKind == Type::STK_BlockPointer 4072 ? CK_BitCast : CK_AnyPointerToBlockPointerCast); 4073 case Type::STK_ObjCObjectPointer: 4074 if (SrcKind == Type::STK_ObjCObjectPointer) 4075 return CK_BitCast; 4076 if (SrcKind == Type::STK_CPointer) 4077 return CK_CPointerToObjCPointerCast; 4078 maybeExtendBlockObject(*this, Src); 4079 return CK_BlockPointerToObjCPointerCast; 4080 case Type::STK_Bool: 4081 return CK_PointerToBoolean; 4082 case Type::STK_Integral: 4083 return CK_PointerToIntegral; 4084 case Type::STK_Floating: 4085 case Type::STK_FloatingComplex: 4086 case Type::STK_IntegralComplex: 4087 case Type::STK_MemberPointer: 4088 llvm_unreachable("illegal cast from pointer"); 4089 } 4090 llvm_unreachable("Should have returned before this"); 4091 4092 case Type::STK_Bool: // casting from bool is like casting from an integer 4093 case Type::STK_Integral: 4094 switch (DestTy->getScalarTypeKind()) { 4095 case Type::STK_CPointer: 4096 case Type::STK_ObjCObjectPointer: 4097 case Type::STK_BlockPointer: 4098 if (Src.get()->isNullPointerConstant(Context, 4099 Expr::NPC_ValueDependentIsNull)) 4100 return CK_NullToPointer; 4101 return CK_IntegralToPointer; 4102 case Type::STK_Bool: 4103 return CK_IntegralToBoolean; 4104 case Type::STK_Integral: 4105 return CK_IntegralCast; 4106 case Type::STK_Floating: 4107 return CK_IntegralToFloating; 4108 case Type::STK_IntegralComplex: 4109 Src = ImpCastExprToType(Src.take(), 4110 DestTy->castAs<ComplexType>()->getElementType(), 4111 CK_IntegralCast); 4112 return CK_IntegralRealToComplex; 4113 case Type::STK_FloatingComplex: 4114 Src = ImpCastExprToType(Src.take(), 4115 DestTy->castAs<ComplexType>()->getElementType(), 4116 CK_IntegralToFloating); 4117 return CK_FloatingRealToComplex; 4118 case Type::STK_MemberPointer: 4119 llvm_unreachable("member pointer type in C"); 4120 } 4121 llvm_unreachable("Should have returned before this"); 4122 4123 case Type::STK_Floating: 4124 switch (DestTy->getScalarTypeKind()) { 4125 case Type::STK_Floating: 4126 return CK_FloatingCast; 4127 case Type::STK_Bool: 4128 return CK_FloatingToBoolean; 4129 case Type::STK_Integral: 4130 return CK_FloatingToIntegral; 4131 case Type::STK_FloatingComplex: 4132 Src = ImpCastExprToType(Src.take(), 4133 DestTy->castAs<ComplexType>()->getElementType(), 4134 CK_FloatingCast); 4135 return CK_FloatingRealToComplex; 4136 case Type::STK_IntegralComplex: 4137 Src = ImpCastExprToType(Src.take(), 4138 DestTy->castAs<ComplexType>()->getElementType(), 4139 CK_FloatingToIntegral); 4140 return CK_IntegralRealToComplex; 4141 case Type::STK_CPointer: 4142 case Type::STK_ObjCObjectPointer: 4143 case Type::STK_BlockPointer: 4144 llvm_unreachable("valid float->pointer cast?"); 4145 case Type::STK_MemberPointer: 4146 llvm_unreachable("member pointer type in C"); 4147 } 4148 llvm_unreachable("Should have returned before this"); 4149 4150 case Type::STK_FloatingComplex: 4151 switch (DestTy->getScalarTypeKind()) { 4152 case Type::STK_FloatingComplex: 4153 return CK_FloatingComplexCast; 4154 case Type::STK_IntegralComplex: 4155 return CK_FloatingComplexToIntegralComplex; 4156 case Type::STK_Floating: { 4157 QualType ET = SrcTy->castAs<ComplexType>()->getElementType(); 4158 if (Context.hasSameType(ET, DestTy)) 4159 return CK_FloatingComplexToReal; 4160 Src = ImpCastExprToType(Src.take(), ET, CK_FloatingComplexToReal); 4161 return CK_FloatingCast; 4162 } 4163 case Type::STK_Bool: 4164 return CK_FloatingComplexToBoolean; 4165 case Type::STK_Integral: 4166 Src = ImpCastExprToType(Src.take(), 4167 SrcTy->castAs<ComplexType>()->getElementType(), 4168 CK_FloatingComplexToReal); 4169 return CK_FloatingToIntegral; 4170 case Type::STK_CPointer: 4171 case Type::STK_ObjCObjectPointer: 4172 case Type::STK_BlockPointer: 4173 llvm_unreachable("valid complex float->pointer cast?"); 4174 case Type::STK_MemberPointer: 4175 llvm_unreachable("member pointer type in C"); 4176 } 4177 llvm_unreachable("Should have returned before this"); 4178 4179 case Type::STK_IntegralComplex: 4180 switch (DestTy->getScalarTypeKind()) { 4181 case Type::STK_FloatingComplex: 4182 return CK_IntegralComplexToFloatingComplex; 4183 case Type::STK_IntegralComplex: 4184 return CK_IntegralComplexCast; 4185 case Type::STK_Integral: { 4186 QualType ET = SrcTy->castAs<ComplexType>()->getElementType(); 4187 if (Context.hasSameType(ET, DestTy)) 4188 return CK_IntegralComplexToReal; 4189 Src = ImpCastExprToType(Src.take(), ET, CK_IntegralComplexToReal); 4190 return CK_IntegralCast; 4191 } 4192 case Type::STK_Bool: 4193 return CK_IntegralComplexToBoolean; 4194 case Type::STK_Floating: 4195 Src = ImpCastExprToType(Src.take(), 4196 SrcTy->castAs<ComplexType>()->getElementType(), 4197 CK_IntegralComplexToReal); 4198 return CK_IntegralToFloating; 4199 case Type::STK_CPointer: 4200 case Type::STK_ObjCObjectPointer: 4201 case Type::STK_BlockPointer: 4202 llvm_unreachable("valid complex int->pointer cast?"); 4203 case Type::STK_MemberPointer: 4204 llvm_unreachable("member pointer type in C"); 4205 } 4206 llvm_unreachable("Should have returned before this"); 4207 } 4208 4209 llvm_unreachable("Unhandled scalar cast"); 4210} 4211 4212bool Sema::CheckVectorCast(SourceRange R, QualType VectorTy, QualType Ty, 4213 CastKind &Kind) { 4214 assert(VectorTy->isVectorType() && "Not a vector type!"); 4215 4216 if (Ty->isVectorType() || Ty->isIntegerType()) { 4217 if (Context.getTypeSize(VectorTy) != Context.getTypeSize(Ty)) 4218 return Diag(R.getBegin(), 4219 Ty->isVectorType() ? 4220 diag::err_invalid_conversion_between_vectors : 4221 diag::err_invalid_conversion_between_vector_and_integer) 4222 << VectorTy << Ty << R; 4223 } else 4224 return Diag(R.getBegin(), 4225 diag::err_invalid_conversion_between_vector_and_scalar) 4226 << VectorTy << Ty << R; 4227 4228 Kind = CK_BitCast; 4229 return false; 4230} 4231 4232ExprResult Sema::CheckExtVectorCast(SourceRange R, QualType DestTy, 4233 Expr *CastExpr, CastKind &Kind) { 4234 assert(DestTy->isExtVectorType() && "Not an extended vector type!"); 4235 4236 QualType SrcTy = CastExpr->getType(); 4237 4238 // If SrcTy is a VectorType, the total size must match to explicitly cast to 4239 // an ExtVectorType. 4240 // In OpenCL, casts between vectors of different types are not allowed. 4241 // (See OpenCL 6.2). 4242 if (SrcTy->isVectorType()) { 4243 if (Context.getTypeSize(DestTy) != Context.getTypeSize(SrcTy) 4244 || (getLangOpts().OpenCL && 4245 (DestTy.getCanonicalType() != SrcTy.getCanonicalType()))) { 4246 Diag(R.getBegin(),diag::err_invalid_conversion_between_ext_vectors) 4247 << DestTy << SrcTy << R; 4248 return ExprError(); 4249 } 4250 Kind = CK_BitCast; 4251 return Owned(CastExpr); 4252 } 4253 4254 // All non-pointer scalars can be cast to ExtVector type. The appropriate 4255 // conversion will take place first from scalar to elt type, and then 4256 // splat from elt type to vector. 4257 if (SrcTy->isPointerType()) 4258 return Diag(R.getBegin(), 4259 diag::err_invalid_conversion_between_vector_and_scalar) 4260 << DestTy << SrcTy << R; 4261 4262 QualType DestElemTy = DestTy->getAs<ExtVectorType>()->getElementType(); 4263 ExprResult CastExprRes = Owned(CastExpr); 4264 CastKind CK = PrepareScalarCast(CastExprRes, DestElemTy); 4265 if (CastExprRes.isInvalid()) 4266 return ExprError(); 4267 CastExpr = ImpCastExprToType(CastExprRes.take(), DestElemTy, CK).take(); 4268 4269 Kind = CK_VectorSplat; 4270 return Owned(CastExpr); 4271} 4272 4273ExprResult 4274Sema::ActOnCastExpr(Scope *S, SourceLocation LParenLoc, 4275 Declarator &D, ParsedType &Ty, 4276 SourceLocation RParenLoc, Expr *CastExpr) { 4277 assert(!D.isInvalidType() && (CastExpr != 0) && 4278 "ActOnCastExpr(): missing type or expr"); 4279 4280 TypeSourceInfo *castTInfo = GetTypeForDeclaratorCast(D, CastExpr->getType()); 4281 if (D.isInvalidType()) 4282 return ExprError(); 4283 4284 if (getLangOpts().CPlusPlus) { 4285 // Check that there are no default arguments (C++ only). 4286 CheckExtraCXXDefaultArguments(D); 4287 } 4288 4289 checkUnusedDeclAttributes(D); 4290 4291 QualType castType = castTInfo->getType(); 4292 Ty = CreateParsedType(castType, castTInfo); 4293 4294 bool isVectorLiteral = false; 4295 4296 // Check for an altivec or OpenCL literal, 4297 // i.e. all the elements are integer constants. 4298 ParenExpr *PE = dyn_cast<ParenExpr>(CastExpr); 4299 ParenListExpr *PLE = dyn_cast<ParenListExpr>(CastExpr); 4300 if ((getLangOpts().AltiVec || getLangOpts().OpenCL) 4301 && castType->isVectorType() && (PE || PLE)) { 4302 if (PLE && PLE->getNumExprs() == 0) { 4303 Diag(PLE->getExprLoc(), diag::err_altivec_empty_initializer); 4304 return ExprError(); 4305 } 4306 if (PE || PLE->getNumExprs() == 1) { 4307 Expr *E = (PE ? PE->getSubExpr() : PLE->getExpr(0)); 4308 if (!E->getType()->isVectorType()) 4309 isVectorLiteral = true; 4310 } 4311 else 4312 isVectorLiteral = true; 4313 } 4314 4315 // If this is a vector initializer, '(' type ')' '(' init, ..., init ')' 4316 // then handle it as such. 4317 if (isVectorLiteral) 4318 return BuildVectorLiteral(LParenLoc, RParenLoc, CastExpr, castTInfo); 4319 4320 // If the Expr being casted is a ParenListExpr, handle it specially. 4321 // This is not an AltiVec-style cast, so turn the ParenListExpr into a 4322 // sequence of BinOp comma operators. 4323 if (isa<ParenListExpr>(CastExpr)) { 4324 ExprResult Result = MaybeConvertParenListExprToParenExpr(S, CastExpr); 4325 if (Result.isInvalid()) return ExprError(); 4326 CastExpr = Result.take(); 4327 } 4328 4329 return BuildCStyleCastExpr(LParenLoc, castTInfo, RParenLoc, CastExpr); 4330} 4331 4332ExprResult Sema::BuildVectorLiteral(SourceLocation LParenLoc, 4333 SourceLocation RParenLoc, Expr *E, 4334 TypeSourceInfo *TInfo) { 4335 assert((isa<ParenListExpr>(E) || isa<ParenExpr>(E)) && 4336 "Expected paren or paren list expression"); 4337 4338 Expr **exprs; 4339 unsigned numExprs; 4340 Expr *subExpr; 4341 if (ParenListExpr *PE = dyn_cast<ParenListExpr>(E)) { 4342 exprs = PE->getExprs(); 4343 numExprs = PE->getNumExprs(); 4344 } else { 4345 subExpr = cast<ParenExpr>(E)->getSubExpr(); 4346 exprs = &subExpr; 4347 numExprs = 1; 4348 } 4349 4350 QualType Ty = TInfo->getType(); 4351 assert(Ty->isVectorType() && "Expected vector type"); 4352 4353 SmallVector<Expr *, 8> initExprs; 4354 const VectorType *VTy = Ty->getAs<VectorType>(); 4355 unsigned numElems = Ty->getAs<VectorType>()->getNumElements(); 4356 4357 // '(...)' form of vector initialization in AltiVec: the number of 4358 // initializers must be one or must match the size of the vector. 4359 // If a single value is specified in the initializer then it will be 4360 // replicated to all the components of the vector 4361 if (VTy->getVectorKind() == VectorType::AltiVecVector) { 4362 // The number of initializers must be one or must match the size of the 4363 // vector. If a single value is specified in the initializer then it will 4364 // be replicated to all the components of the vector 4365 if (numExprs == 1) { 4366 QualType ElemTy = Ty->getAs<VectorType>()->getElementType(); 4367 ExprResult Literal = DefaultLvalueConversion(exprs[0]); 4368 if (Literal.isInvalid()) 4369 return ExprError(); 4370 Literal = ImpCastExprToType(Literal.take(), ElemTy, 4371 PrepareScalarCast(Literal, ElemTy)); 4372 return BuildCStyleCastExpr(LParenLoc, TInfo, RParenLoc, Literal.take()); 4373 } 4374 else if (numExprs < numElems) { 4375 Diag(E->getExprLoc(), 4376 diag::err_incorrect_number_of_vector_initializers); 4377 return ExprError(); 4378 } 4379 else 4380 initExprs.append(exprs, exprs + numExprs); 4381 } 4382 else { 4383 // For OpenCL, when the number of initializers is a single value, 4384 // it will be replicated to all components of the vector. 4385 if (getLangOpts().OpenCL && 4386 VTy->getVectorKind() == VectorType::GenericVector && 4387 numExprs == 1) { 4388 QualType ElemTy = Ty->getAs<VectorType>()->getElementType(); 4389 ExprResult Literal = DefaultLvalueConversion(exprs[0]); 4390 if (Literal.isInvalid()) 4391 return ExprError(); 4392 Literal = ImpCastExprToType(Literal.take(), ElemTy, 4393 PrepareScalarCast(Literal, ElemTy)); 4394 return BuildCStyleCastExpr(LParenLoc, TInfo, RParenLoc, Literal.take()); 4395 } 4396 4397 initExprs.append(exprs, exprs + numExprs); 4398 } 4399 // FIXME: This means that pretty-printing the final AST will produce curly 4400 // braces instead of the original commas. 4401 InitListExpr *initE = new (Context) InitListExpr(Context, LParenLoc, 4402 &initExprs[0], 4403 initExprs.size(), RParenLoc); 4404 initE->setType(Ty); 4405 return BuildCompoundLiteralExpr(LParenLoc, TInfo, RParenLoc, initE); 4406} 4407 4408/// This is not an AltiVec-style cast or or C++ direct-initialization, so turn 4409/// the ParenListExpr into a sequence of comma binary operators. 4410ExprResult 4411Sema::MaybeConvertParenListExprToParenExpr(Scope *S, Expr *OrigExpr) { 4412 ParenListExpr *E = dyn_cast<ParenListExpr>(OrigExpr); 4413 if (!E) 4414 return Owned(OrigExpr); 4415 4416 ExprResult Result(E->getExpr(0)); 4417 4418 for (unsigned i = 1, e = E->getNumExprs(); i != e && !Result.isInvalid(); ++i) 4419 Result = ActOnBinOp(S, E->getExprLoc(), tok::comma, Result.get(), 4420 E->getExpr(i)); 4421 4422 if (Result.isInvalid()) return ExprError(); 4423 4424 return ActOnParenExpr(E->getLParenLoc(), E->getRParenLoc(), Result.get()); 4425} 4426 4427ExprResult Sema::ActOnParenListExpr(SourceLocation L, 4428 SourceLocation R, 4429 MultiExprArg Val) { 4430 unsigned nexprs = Val.size(); 4431 Expr **exprs = reinterpret_cast<Expr**>(Val.release()); 4432 assert((exprs != 0) && "ActOnParenOrParenListExpr() missing expr list"); 4433 Expr *expr = new (Context) ParenListExpr(Context, L, exprs, nexprs, R); 4434 return Owned(expr); 4435} 4436 4437/// \brief Emit a specialized diagnostic when one expression is a null pointer 4438/// constant and the other is not a pointer. Returns true if a diagnostic is 4439/// emitted. 4440bool Sema::DiagnoseConditionalForNull(Expr *LHSExpr, Expr *RHSExpr, 4441 SourceLocation QuestionLoc) { 4442 Expr *NullExpr = LHSExpr; 4443 Expr *NonPointerExpr = RHSExpr; 4444 Expr::NullPointerConstantKind NullKind = 4445 NullExpr->isNullPointerConstant(Context, 4446 Expr::NPC_ValueDependentIsNotNull); 4447 4448 if (NullKind == Expr::NPCK_NotNull) { 4449 NullExpr = RHSExpr; 4450 NonPointerExpr = LHSExpr; 4451 NullKind = 4452 NullExpr->isNullPointerConstant(Context, 4453 Expr::NPC_ValueDependentIsNotNull); 4454 } 4455 4456 if (NullKind == Expr::NPCK_NotNull) 4457 return false; 4458 4459 if (NullKind == Expr::NPCK_ZeroInteger) { 4460 // In this case, check to make sure that we got here from a "NULL" 4461 // string in the source code. 4462 NullExpr = NullExpr->IgnoreParenImpCasts(); 4463 SourceLocation loc = NullExpr->getExprLoc(); 4464 if (!findMacroSpelling(loc, "NULL")) 4465 return false; 4466 } 4467 4468 int DiagType = (NullKind == Expr::NPCK_CXX0X_nullptr); 4469 Diag(QuestionLoc, diag::err_typecheck_cond_incompatible_operands_null) 4470 << NonPointerExpr->getType() << DiagType 4471 << NonPointerExpr->getSourceRange(); 4472 return true; 4473} 4474 4475/// \brief Return false if the condition expression is valid, true otherwise. 4476static bool checkCondition(Sema &S, Expr *Cond) { 4477 QualType CondTy = Cond->getType(); 4478 4479 // C99 6.5.15p2 4480 if (CondTy->isScalarType()) return false; 4481 4482 // OpenCL: Sec 6.3.i says the condition is allowed to be a vector or scalar. 4483 if (S.getLangOpts().OpenCL && CondTy->isVectorType()) 4484 return false; 4485 4486 // Emit the proper error message. 4487 S.Diag(Cond->getLocStart(), S.getLangOpts().OpenCL ? 4488 diag::err_typecheck_cond_expect_scalar : 4489 diag::err_typecheck_cond_expect_scalar_or_vector) 4490 << CondTy; 4491 return true; 4492} 4493 4494/// \brief Return false if the two expressions can be converted to a vector, 4495/// true otherwise 4496static bool checkConditionalConvertScalarsToVectors(Sema &S, ExprResult &LHS, 4497 ExprResult &RHS, 4498 QualType CondTy) { 4499 // Both operands should be of scalar type. 4500 if (!LHS.get()->getType()->isScalarType()) { 4501 S.Diag(LHS.get()->getLocStart(), diag::err_typecheck_cond_expect_scalar) 4502 << CondTy; 4503 return true; 4504 } 4505 if (!RHS.get()->getType()->isScalarType()) { 4506 S.Diag(RHS.get()->getLocStart(), diag::err_typecheck_cond_expect_scalar) 4507 << CondTy; 4508 return true; 4509 } 4510 4511 // Implicity convert these scalars to the type of the condition. 4512 LHS = S.ImpCastExprToType(LHS.take(), CondTy, CK_IntegralCast); 4513 RHS = S.ImpCastExprToType(RHS.take(), CondTy, CK_IntegralCast); 4514 return false; 4515} 4516 4517/// \brief Handle when one or both operands are void type. 4518static QualType checkConditionalVoidType(Sema &S, ExprResult &LHS, 4519 ExprResult &RHS) { 4520 Expr *LHSExpr = LHS.get(); 4521 Expr *RHSExpr = RHS.get(); 4522 4523 if (!LHSExpr->getType()->isVoidType()) 4524 S.Diag(RHSExpr->getLocStart(), diag::ext_typecheck_cond_one_void) 4525 << RHSExpr->getSourceRange(); 4526 if (!RHSExpr->getType()->isVoidType()) 4527 S.Diag(LHSExpr->getLocStart(), diag::ext_typecheck_cond_one_void) 4528 << LHSExpr->getSourceRange(); 4529 LHS = S.ImpCastExprToType(LHS.take(), S.Context.VoidTy, CK_ToVoid); 4530 RHS = S.ImpCastExprToType(RHS.take(), S.Context.VoidTy, CK_ToVoid); 4531 return S.Context.VoidTy; 4532} 4533 4534/// \brief Return false if the NullExpr can be promoted to PointerTy, 4535/// true otherwise. 4536static bool checkConditionalNullPointer(Sema &S, ExprResult &NullExpr, 4537 QualType PointerTy) { 4538 if ((!PointerTy->isAnyPointerType() && !PointerTy->isBlockPointerType()) || 4539 !NullExpr.get()->isNullPointerConstant(S.Context, 4540 Expr::NPC_ValueDependentIsNull)) 4541 return true; 4542 4543 NullExpr = S.ImpCastExprToType(NullExpr.take(), PointerTy, CK_NullToPointer); 4544 return false; 4545} 4546 4547/// \brief Checks compatibility between two pointers and return the resulting 4548/// type. 4549static QualType checkConditionalPointerCompatibility(Sema &S, ExprResult &LHS, 4550 ExprResult &RHS, 4551 SourceLocation Loc) { 4552 QualType LHSTy = LHS.get()->getType(); 4553 QualType RHSTy = RHS.get()->getType(); 4554 4555 if (S.Context.hasSameType(LHSTy, RHSTy)) { 4556 // Two identical pointers types are always compatible. 4557 return LHSTy; 4558 } 4559 4560 QualType lhptee, rhptee; 4561 4562 // Get the pointee types. 4563 if (const BlockPointerType *LHSBTy = LHSTy->getAs<BlockPointerType>()) { 4564 lhptee = LHSBTy->getPointeeType(); 4565 rhptee = RHSTy->castAs<BlockPointerType>()->getPointeeType(); 4566 } else { 4567 lhptee = LHSTy->castAs<PointerType>()->getPointeeType(); 4568 rhptee = RHSTy->castAs<PointerType>()->getPointeeType(); 4569 } 4570 4571 // C99 6.5.15p6: If both operands are pointers to compatible types or to 4572 // differently qualified versions of compatible types, the result type is 4573 // a pointer to an appropriately qualified version of the composite 4574 // type. 4575 4576 // Only CVR-qualifiers exist in the standard, and the differently-qualified 4577 // clause doesn't make sense for our extensions. E.g. address space 2 should 4578 // be incompatible with address space 3: they may live on different devices or 4579 // anything. 4580 Qualifiers lhQual = lhptee.getQualifiers(); 4581 Qualifiers rhQual = rhptee.getQualifiers(); 4582 4583 unsigned MergedCVRQual = lhQual.getCVRQualifiers() | rhQual.getCVRQualifiers(); 4584 lhQual.removeCVRQualifiers(); 4585 rhQual.removeCVRQualifiers(); 4586 4587 lhptee = S.Context.getQualifiedType(lhptee.getUnqualifiedType(), lhQual); 4588 rhptee = S.Context.getQualifiedType(rhptee.getUnqualifiedType(), rhQual); 4589 4590 QualType CompositeTy = S.Context.mergeTypes(lhptee, rhptee); 4591 4592 if (CompositeTy.isNull()) { 4593 S.Diag(Loc, diag::warn_typecheck_cond_incompatible_pointers) 4594 << LHSTy << RHSTy << LHS.get()->getSourceRange() 4595 << RHS.get()->getSourceRange(); 4596 // In this situation, we assume void* type. No especially good 4597 // reason, but this is what gcc does, and we do have to pick 4598 // to get a consistent AST. 4599 QualType incompatTy = S.Context.getPointerType(S.Context.VoidTy); 4600 LHS = S.ImpCastExprToType(LHS.take(), incompatTy, CK_BitCast); 4601 RHS = S.ImpCastExprToType(RHS.take(), incompatTy, CK_BitCast); 4602 return incompatTy; 4603 } 4604 4605 // The pointer types are compatible. 4606 QualType ResultTy = CompositeTy.withCVRQualifiers(MergedCVRQual); 4607 ResultTy = S.Context.getPointerType(ResultTy); 4608 4609 LHS = S.ImpCastExprToType(LHS.take(), ResultTy, CK_BitCast); 4610 RHS = S.ImpCastExprToType(RHS.take(), ResultTy, CK_BitCast); 4611 return ResultTy; 4612} 4613 4614/// \brief Return the resulting type when the operands are both block pointers. 4615static QualType checkConditionalBlockPointerCompatibility(Sema &S, 4616 ExprResult &LHS, 4617 ExprResult &RHS, 4618 SourceLocation Loc) { 4619 QualType LHSTy = LHS.get()->getType(); 4620 QualType RHSTy = RHS.get()->getType(); 4621 4622 if (!LHSTy->isBlockPointerType() || !RHSTy->isBlockPointerType()) { 4623 if (LHSTy->isVoidPointerType() || RHSTy->isVoidPointerType()) { 4624 QualType destType = S.Context.getPointerType(S.Context.VoidTy); 4625 LHS = S.ImpCastExprToType(LHS.take(), destType, CK_BitCast); 4626 RHS = S.ImpCastExprToType(RHS.take(), destType, CK_BitCast); 4627 return destType; 4628 } 4629 S.Diag(Loc, diag::err_typecheck_cond_incompatible_operands) 4630 << LHSTy << RHSTy << LHS.get()->getSourceRange() 4631 << RHS.get()->getSourceRange(); 4632 return QualType(); 4633 } 4634 4635 // We have 2 block pointer types. 4636 return checkConditionalPointerCompatibility(S, LHS, RHS, Loc); 4637} 4638 4639/// \brief Return the resulting type when the operands are both pointers. 4640static QualType 4641checkConditionalObjectPointersCompatibility(Sema &S, ExprResult &LHS, 4642 ExprResult &RHS, 4643 SourceLocation Loc) { 4644 // get the pointer types 4645 QualType LHSTy = LHS.get()->getType(); 4646 QualType RHSTy = RHS.get()->getType(); 4647 4648 // get the "pointed to" types 4649 QualType lhptee = LHSTy->getAs<PointerType>()->getPointeeType(); 4650 QualType rhptee = RHSTy->getAs<PointerType>()->getPointeeType(); 4651 4652 // ignore qualifiers on void (C99 6.5.15p3, clause 6) 4653 if (lhptee->isVoidType() && rhptee->isIncompleteOrObjectType()) { 4654 // Figure out necessary qualifiers (C99 6.5.15p6) 4655 QualType destPointee 4656 = S.Context.getQualifiedType(lhptee, rhptee.getQualifiers()); 4657 QualType destType = S.Context.getPointerType(destPointee); 4658 // Add qualifiers if necessary. 4659 LHS = S.ImpCastExprToType(LHS.take(), destType, CK_NoOp); 4660 // Promote to void*. 4661 RHS = S.ImpCastExprToType(RHS.take(), destType, CK_BitCast); 4662 return destType; 4663 } 4664 if (rhptee->isVoidType() && lhptee->isIncompleteOrObjectType()) { 4665 QualType destPointee 4666 = S.Context.getQualifiedType(rhptee, lhptee.getQualifiers()); 4667 QualType destType = S.Context.getPointerType(destPointee); 4668 // Add qualifiers if necessary. 4669 RHS = S.ImpCastExprToType(RHS.take(), destType, CK_NoOp); 4670 // Promote to void*. 4671 LHS = S.ImpCastExprToType(LHS.take(), destType, CK_BitCast); 4672 return destType; 4673 } 4674 4675 return checkConditionalPointerCompatibility(S, LHS, RHS, Loc); 4676} 4677 4678/// \brief Return false if the first expression is not an integer and the second 4679/// expression is not a pointer, true otherwise. 4680static bool checkPointerIntegerMismatch(Sema &S, ExprResult &Int, 4681 Expr* PointerExpr, SourceLocation Loc, 4682 bool IsIntFirstExpr) { 4683 if (!PointerExpr->getType()->isPointerType() || 4684 !Int.get()->getType()->isIntegerType()) 4685 return false; 4686 4687 Expr *Expr1 = IsIntFirstExpr ? Int.get() : PointerExpr; 4688 Expr *Expr2 = IsIntFirstExpr ? PointerExpr : Int.get(); 4689 4690 S.Diag(Loc, diag::warn_typecheck_cond_pointer_integer_mismatch) 4691 << Expr1->getType() << Expr2->getType() 4692 << Expr1->getSourceRange() << Expr2->getSourceRange(); 4693 Int = S.ImpCastExprToType(Int.take(), PointerExpr->getType(), 4694 CK_IntegralToPointer); 4695 return true; 4696} 4697 4698/// Note that LHS is not null here, even if this is the gnu "x ?: y" extension. 4699/// In that case, LHS = cond. 4700/// C99 6.5.15 4701QualType Sema::CheckConditionalOperands(ExprResult &Cond, ExprResult &LHS, 4702 ExprResult &RHS, ExprValueKind &VK, 4703 ExprObjectKind &OK, 4704 SourceLocation QuestionLoc) { 4705 4706 ExprResult LHSResult = CheckPlaceholderExpr(LHS.get()); 4707 if (!LHSResult.isUsable()) return QualType(); 4708 LHS = move(LHSResult); 4709 4710 ExprResult RHSResult = CheckPlaceholderExpr(RHS.get()); 4711 if (!RHSResult.isUsable()) return QualType(); 4712 RHS = move(RHSResult); 4713 4714 // C++ is sufficiently different to merit its own checker. 4715 if (getLangOpts().CPlusPlus) 4716 return CXXCheckConditionalOperands(Cond, LHS, RHS, VK, OK, QuestionLoc); 4717 4718 VK = VK_RValue; 4719 OK = OK_Ordinary; 4720 4721 Cond = UsualUnaryConversions(Cond.take()); 4722 if (Cond.isInvalid()) 4723 return QualType(); 4724 LHS = UsualUnaryConversions(LHS.take()); 4725 if (LHS.isInvalid()) 4726 return QualType(); 4727 RHS = UsualUnaryConversions(RHS.take()); 4728 if (RHS.isInvalid()) 4729 return QualType(); 4730 4731 QualType CondTy = Cond.get()->getType(); 4732 QualType LHSTy = LHS.get()->getType(); 4733 QualType RHSTy = RHS.get()->getType(); 4734 4735 // first, check the condition. 4736 if (checkCondition(*this, Cond.get())) 4737 return QualType(); 4738 4739 // Now check the two expressions. 4740 if (LHSTy->isVectorType() || RHSTy->isVectorType()) 4741 return CheckVectorOperands(LHS, RHS, QuestionLoc, /*isCompAssign*/false); 4742 4743 // OpenCL: If the condition is a vector, and both operands are scalar, 4744 // attempt to implicity convert them to the vector type to act like the 4745 // built in select. 4746 if (getLangOpts().OpenCL && CondTy->isVectorType()) 4747 if (checkConditionalConvertScalarsToVectors(*this, LHS, RHS, CondTy)) 4748 return QualType(); 4749 4750 // If both operands have arithmetic type, do the usual arithmetic conversions 4751 // to find a common type: C99 6.5.15p3,5. 4752 if (LHSTy->isArithmeticType() && RHSTy->isArithmeticType()) { 4753 UsualArithmeticConversions(LHS, RHS); 4754 if (LHS.isInvalid() || RHS.isInvalid()) 4755 return QualType(); 4756 return LHS.get()->getType(); 4757 } 4758 4759 // If both operands are the same structure or union type, the result is that 4760 // type. 4761 if (const RecordType *LHSRT = LHSTy->getAs<RecordType>()) { // C99 6.5.15p3 4762 if (const RecordType *RHSRT = RHSTy->getAs<RecordType>()) 4763 if (LHSRT->getDecl() == RHSRT->getDecl()) 4764 // "If both the operands have structure or union type, the result has 4765 // that type." This implies that CV qualifiers are dropped. 4766 return LHSTy.getUnqualifiedType(); 4767 // FIXME: Type of conditional expression must be complete in C mode. 4768 } 4769 4770 // C99 6.5.15p5: "If both operands have void type, the result has void type." 4771 // The following || allows only one side to be void (a GCC-ism). 4772 if (LHSTy->isVoidType() || RHSTy->isVoidType()) { 4773 return checkConditionalVoidType(*this, LHS, RHS); 4774 } 4775 4776 // C99 6.5.15p6 - "if one operand is a null pointer constant, the result has 4777 // the type of the other operand." 4778 if (!checkConditionalNullPointer(*this, RHS, LHSTy)) return LHSTy; 4779 if (!checkConditionalNullPointer(*this, LHS, RHSTy)) return RHSTy; 4780 4781 // All objective-c pointer type analysis is done here. 4782 QualType compositeType = FindCompositeObjCPointerType(LHS, RHS, 4783 QuestionLoc); 4784 if (LHS.isInvalid() || RHS.isInvalid()) 4785 return QualType(); 4786 if (!compositeType.isNull()) 4787 return compositeType; 4788 4789 4790 // Handle block pointer types. 4791 if (LHSTy->isBlockPointerType() || RHSTy->isBlockPointerType()) 4792 return checkConditionalBlockPointerCompatibility(*this, LHS, RHS, 4793 QuestionLoc); 4794 4795 // Check constraints for C object pointers types (C99 6.5.15p3,6). 4796 if (LHSTy->isPointerType() && RHSTy->isPointerType()) 4797 return checkConditionalObjectPointersCompatibility(*this, LHS, RHS, 4798 QuestionLoc); 4799 4800 // GCC compatibility: soften pointer/integer mismatch. Note that 4801 // null pointers have been filtered out by this point. 4802 if (checkPointerIntegerMismatch(*this, LHS, RHS.get(), QuestionLoc, 4803 /*isIntFirstExpr=*/true)) 4804 return RHSTy; 4805 if (checkPointerIntegerMismatch(*this, RHS, LHS.get(), QuestionLoc, 4806 /*isIntFirstExpr=*/false)) 4807 return LHSTy; 4808 4809 // Emit a better diagnostic if one of the expressions is a null pointer 4810 // constant and the other is not a pointer type. In this case, the user most 4811 // likely forgot to take the address of the other expression. 4812 if (DiagnoseConditionalForNull(LHS.get(), RHS.get(), QuestionLoc)) 4813 return QualType(); 4814 4815 // Otherwise, the operands are not compatible. 4816 Diag(QuestionLoc, diag::err_typecheck_cond_incompatible_operands) 4817 << LHSTy << RHSTy << LHS.get()->getSourceRange() 4818 << RHS.get()->getSourceRange(); 4819 return QualType(); 4820} 4821 4822/// FindCompositeObjCPointerType - Helper method to find composite type of 4823/// two objective-c pointer types of the two input expressions. 4824QualType Sema::FindCompositeObjCPointerType(ExprResult &LHS, ExprResult &RHS, 4825 SourceLocation QuestionLoc) { 4826 QualType LHSTy = LHS.get()->getType(); 4827 QualType RHSTy = RHS.get()->getType(); 4828 4829 // Handle things like Class and struct objc_class*. Here we case the result 4830 // to the pseudo-builtin, because that will be implicitly cast back to the 4831 // redefinition type if an attempt is made to access its fields. 4832 if (LHSTy->isObjCClassType() && 4833 (Context.hasSameType(RHSTy, Context.getObjCClassRedefinitionType()))) { 4834 RHS = ImpCastExprToType(RHS.take(), LHSTy, CK_CPointerToObjCPointerCast); 4835 return LHSTy; 4836 } 4837 if (RHSTy->isObjCClassType() && 4838 (Context.hasSameType(LHSTy, Context.getObjCClassRedefinitionType()))) { 4839 LHS = ImpCastExprToType(LHS.take(), RHSTy, CK_CPointerToObjCPointerCast); 4840 return RHSTy; 4841 } 4842 // And the same for struct objc_object* / id 4843 if (LHSTy->isObjCIdType() && 4844 (Context.hasSameType(RHSTy, Context.getObjCIdRedefinitionType()))) { 4845 RHS = ImpCastExprToType(RHS.take(), LHSTy, CK_CPointerToObjCPointerCast); 4846 return LHSTy; 4847 } 4848 if (RHSTy->isObjCIdType() && 4849 (Context.hasSameType(LHSTy, Context.getObjCIdRedefinitionType()))) { 4850 LHS = ImpCastExprToType(LHS.take(), RHSTy, CK_CPointerToObjCPointerCast); 4851 return RHSTy; 4852 } 4853 // And the same for struct objc_selector* / SEL 4854 if (Context.isObjCSelType(LHSTy) && 4855 (Context.hasSameType(RHSTy, Context.getObjCSelRedefinitionType()))) { 4856 RHS = ImpCastExprToType(RHS.take(), LHSTy, CK_BitCast); 4857 return LHSTy; 4858 } 4859 if (Context.isObjCSelType(RHSTy) && 4860 (Context.hasSameType(LHSTy, Context.getObjCSelRedefinitionType()))) { 4861 LHS = ImpCastExprToType(LHS.take(), RHSTy, CK_BitCast); 4862 return RHSTy; 4863 } 4864 // Check constraints for Objective-C object pointers types. 4865 if (LHSTy->isObjCObjectPointerType() && RHSTy->isObjCObjectPointerType()) { 4866 4867 if (Context.getCanonicalType(LHSTy) == Context.getCanonicalType(RHSTy)) { 4868 // Two identical object pointer types are always compatible. 4869 return LHSTy; 4870 } 4871 const ObjCObjectPointerType *LHSOPT = LHSTy->castAs<ObjCObjectPointerType>(); 4872 const ObjCObjectPointerType *RHSOPT = RHSTy->castAs<ObjCObjectPointerType>(); 4873 QualType compositeType = LHSTy; 4874 4875 // If both operands are interfaces and either operand can be 4876 // assigned to the other, use that type as the composite 4877 // type. This allows 4878 // xxx ? (A*) a : (B*) b 4879 // where B is a subclass of A. 4880 // 4881 // Additionally, as for assignment, if either type is 'id' 4882 // allow silent coercion. Finally, if the types are 4883 // incompatible then make sure to use 'id' as the composite 4884 // type so the result is acceptable for sending messages to. 4885 4886 // FIXME: Consider unifying with 'areComparableObjCPointerTypes'. 4887 // It could return the composite type. 4888 if (Context.canAssignObjCInterfaces(LHSOPT, RHSOPT)) { 4889 compositeType = RHSOPT->isObjCBuiltinType() ? RHSTy : LHSTy; 4890 } else if (Context.canAssignObjCInterfaces(RHSOPT, LHSOPT)) { 4891 compositeType = LHSOPT->isObjCBuiltinType() ? LHSTy : RHSTy; 4892 } else if ((LHSTy->isObjCQualifiedIdType() || 4893 RHSTy->isObjCQualifiedIdType()) && 4894 Context.ObjCQualifiedIdTypesAreCompatible(LHSTy, RHSTy, true)) { 4895 // Need to handle "id<xx>" explicitly. 4896 // GCC allows qualified id and any Objective-C type to devolve to 4897 // id. Currently localizing to here until clear this should be 4898 // part of ObjCQualifiedIdTypesAreCompatible. 4899 compositeType = Context.getObjCIdType(); 4900 } else if (LHSTy->isObjCIdType() || RHSTy->isObjCIdType()) { 4901 compositeType = Context.getObjCIdType(); 4902 } else if (!(compositeType = 4903 Context.areCommonBaseCompatible(LHSOPT, RHSOPT)).isNull()) 4904 ; 4905 else { 4906 Diag(QuestionLoc, diag::ext_typecheck_cond_incompatible_operands) 4907 << LHSTy << RHSTy 4908 << LHS.get()->getSourceRange() << RHS.get()->getSourceRange(); 4909 QualType incompatTy = Context.getObjCIdType(); 4910 LHS = ImpCastExprToType(LHS.take(), incompatTy, CK_BitCast); 4911 RHS = ImpCastExprToType(RHS.take(), incompatTy, CK_BitCast); 4912 return incompatTy; 4913 } 4914 // The object pointer types are compatible. 4915 LHS = ImpCastExprToType(LHS.take(), compositeType, CK_BitCast); 4916 RHS = ImpCastExprToType(RHS.take(), compositeType, CK_BitCast); 4917 return compositeType; 4918 } 4919 // Check Objective-C object pointer types and 'void *' 4920 if (LHSTy->isVoidPointerType() && RHSTy->isObjCObjectPointerType()) { 4921 if (getLangOpts().ObjCAutoRefCount) { 4922 // ARC forbids the implicit conversion of object pointers to 'void *', 4923 // so these types are not compatible. 4924 Diag(QuestionLoc, diag::err_cond_voidptr_arc) << LHSTy << RHSTy 4925 << LHS.get()->getSourceRange() << RHS.get()->getSourceRange(); 4926 LHS = RHS = true; 4927 return QualType(); 4928 } 4929 QualType lhptee = LHSTy->getAs<PointerType>()->getPointeeType(); 4930 QualType rhptee = RHSTy->getAs<ObjCObjectPointerType>()->getPointeeType(); 4931 QualType destPointee 4932 = Context.getQualifiedType(lhptee, rhptee.getQualifiers()); 4933 QualType destType = Context.getPointerType(destPointee); 4934 // Add qualifiers if necessary. 4935 LHS = ImpCastExprToType(LHS.take(), destType, CK_NoOp); 4936 // Promote to void*. 4937 RHS = ImpCastExprToType(RHS.take(), destType, CK_BitCast); 4938 return destType; 4939 } 4940 if (LHSTy->isObjCObjectPointerType() && RHSTy->isVoidPointerType()) { 4941 if (getLangOpts().ObjCAutoRefCount) { 4942 // ARC forbids the implicit conversion of object pointers to 'void *', 4943 // so these types are not compatible. 4944 Diag(QuestionLoc, diag::err_cond_voidptr_arc) << LHSTy << RHSTy 4945 << LHS.get()->getSourceRange() << RHS.get()->getSourceRange(); 4946 LHS = RHS = true; 4947 return QualType(); 4948 } 4949 QualType lhptee = LHSTy->getAs<ObjCObjectPointerType>()->getPointeeType(); 4950 QualType rhptee = RHSTy->getAs<PointerType>()->getPointeeType(); 4951 QualType destPointee 4952 = Context.getQualifiedType(rhptee, lhptee.getQualifiers()); 4953 QualType destType = Context.getPointerType(destPointee); 4954 // Add qualifiers if necessary. 4955 RHS = ImpCastExprToType(RHS.take(), destType, CK_NoOp); 4956 // Promote to void*. 4957 LHS = ImpCastExprToType(LHS.take(), destType, CK_BitCast); 4958 return destType; 4959 } 4960 return QualType(); 4961} 4962 4963/// SuggestParentheses - Emit a note with a fixit hint that wraps 4964/// ParenRange in parentheses. 4965static void SuggestParentheses(Sema &Self, SourceLocation Loc, 4966 const PartialDiagnostic &Note, 4967 SourceRange ParenRange) { 4968 SourceLocation EndLoc = Self.PP.getLocForEndOfToken(ParenRange.getEnd()); 4969 if (ParenRange.getBegin().isFileID() && ParenRange.getEnd().isFileID() && 4970 EndLoc.isValid()) { 4971 Self.Diag(Loc, Note) 4972 << FixItHint::CreateInsertion(ParenRange.getBegin(), "(") 4973 << FixItHint::CreateInsertion(EndLoc, ")"); 4974 } else { 4975 // We can't display the parentheses, so just show the bare note. 4976 Self.Diag(Loc, Note) << ParenRange; 4977 } 4978} 4979 4980static bool IsArithmeticOp(BinaryOperatorKind Opc) { 4981 return Opc >= BO_Mul && Opc <= BO_Shr; 4982} 4983 4984/// IsArithmeticBinaryExpr - Returns true if E is an arithmetic binary 4985/// expression, either using a built-in or overloaded operator, 4986/// and sets *OpCode to the opcode and *RHSExprs to the right-hand side 4987/// expression. 4988static bool IsArithmeticBinaryExpr(Expr *E, BinaryOperatorKind *Opcode, 4989 Expr **RHSExprs) { 4990 // Don't strip parenthesis: we should not warn if E is in parenthesis. 4991 E = E->IgnoreImpCasts(); 4992 E = E->IgnoreConversionOperator(); 4993 E = E->IgnoreImpCasts(); 4994 4995 // Built-in binary operator. 4996 if (BinaryOperator *OP = dyn_cast<BinaryOperator>(E)) { 4997 if (IsArithmeticOp(OP->getOpcode())) { 4998 *Opcode = OP->getOpcode(); 4999 *RHSExprs = OP->getRHS(); 5000 return true; 5001 } 5002 } 5003 5004 // Overloaded operator. 5005 if (CXXOperatorCallExpr *Call = dyn_cast<CXXOperatorCallExpr>(E)) { 5006 if (Call->getNumArgs() != 2) 5007 return false; 5008 5009 // Make sure this is really a binary operator that is safe to pass into 5010 // BinaryOperator::getOverloadedOpcode(), e.g. it's not a subscript op. 5011 OverloadedOperatorKind OO = Call->getOperator(); 5012 if (OO < OO_Plus || OO > OO_Arrow) 5013 return false; 5014 5015 BinaryOperatorKind OpKind = BinaryOperator::getOverloadedOpcode(OO); 5016 if (IsArithmeticOp(OpKind)) { 5017 *Opcode = OpKind; 5018 *RHSExprs = Call->getArg(1); 5019 return true; 5020 } 5021 } 5022 5023 return false; 5024} 5025 5026static bool IsLogicOp(BinaryOperatorKind Opc) { 5027 return (Opc >= BO_LT && Opc <= BO_NE) || (Opc >= BO_LAnd && Opc <= BO_LOr); 5028} 5029 5030/// ExprLooksBoolean - Returns true if E looks boolean, i.e. it has boolean type 5031/// or is a logical expression such as (x==y) which has int type, but is 5032/// commonly interpreted as boolean. 5033static bool ExprLooksBoolean(Expr *E) { 5034 E = E->IgnoreParenImpCasts(); 5035 5036 if (E->getType()->isBooleanType()) 5037 return true; 5038 if (BinaryOperator *OP = dyn_cast<BinaryOperator>(E)) 5039 return IsLogicOp(OP->getOpcode()); 5040 if (UnaryOperator *OP = dyn_cast<UnaryOperator>(E)) 5041 return OP->getOpcode() == UO_LNot; 5042 5043 return false; 5044} 5045 5046/// DiagnoseConditionalPrecedence - Emit a warning when a conditional operator 5047/// and binary operator are mixed in a way that suggests the programmer assumed 5048/// the conditional operator has higher precedence, for example: 5049/// "int x = a + someBinaryCondition ? 1 : 2". 5050static void DiagnoseConditionalPrecedence(Sema &Self, 5051 SourceLocation OpLoc, 5052 Expr *Condition, 5053 Expr *LHSExpr, 5054 Expr *RHSExpr) { 5055 BinaryOperatorKind CondOpcode; 5056 Expr *CondRHS; 5057 5058 if (!IsArithmeticBinaryExpr(Condition, &CondOpcode, &CondRHS)) 5059 return; 5060 if (!ExprLooksBoolean(CondRHS)) 5061 return; 5062 5063 // The condition is an arithmetic binary expression, with a right- 5064 // hand side that looks boolean, so warn. 5065 5066 Self.Diag(OpLoc, diag::warn_precedence_conditional) 5067 << Condition->getSourceRange() 5068 << BinaryOperator::getOpcodeStr(CondOpcode); 5069 5070 SuggestParentheses(Self, OpLoc, 5071 Self.PDiag(diag::note_precedence_conditional_silence) 5072 << BinaryOperator::getOpcodeStr(CondOpcode), 5073 SourceRange(Condition->getLocStart(), Condition->getLocEnd())); 5074 5075 SuggestParentheses(Self, OpLoc, 5076 Self.PDiag(diag::note_precedence_conditional_first), 5077 SourceRange(CondRHS->getLocStart(), RHSExpr->getLocEnd())); 5078} 5079 5080/// ActOnConditionalOp - Parse a ?: operation. Note that 'LHS' may be null 5081/// in the case of a the GNU conditional expr extension. 5082ExprResult Sema::ActOnConditionalOp(SourceLocation QuestionLoc, 5083 SourceLocation ColonLoc, 5084 Expr *CondExpr, Expr *LHSExpr, 5085 Expr *RHSExpr) { 5086 // If this is the gnu "x ?: y" extension, analyze the types as though the LHS 5087 // was the condition. 5088 OpaqueValueExpr *opaqueValue = 0; 5089 Expr *commonExpr = 0; 5090 if (LHSExpr == 0) { 5091 commonExpr = CondExpr; 5092 5093 // We usually want to apply unary conversions *before* saving, except 5094 // in the special case of a C++ l-value conditional. 5095 if (!(getLangOpts().CPlusPlus 5096 && !commonExpr->isTypeDependent() 5097 && commonExpr->getValueKind() == RHSExpr->getValueKind() 5098 && commonExpr->isGLValue() 5099 && commonExpr->isOrdinaryOrBitFieldObject() 5100 && RHSExpr->isOrdinaryOrBitFieldObject() 5101 && Context.hasSameType(commonExpr->getType(), RHSExpr->getType()))) { 5102 ExprResult commonRes = UsualUnaryConversions(commonExpr); 5103 if (commonRes.isInvalid()) 5104 return ExprError(); 5105 commonExpr = commonRes.take(); 5106 } 5107 5108 opaqueValue = new (Context) OpaqueValueExpr(commonExpr->getExprLoc(), 5109 commonExpr->getType(), 5110 commonExpr->getValueKind(), 5111 commonExpr->getObjectKind(), 5112 commonExpr); 5113 LHSExpr = CondExpr = opaqueValue; 5114 } 5115 5116 ExprValueKind VK = VK_RValue; 5117 ExprObjectKind OK = OK_Ordinary; 5118 ExprResult Cond = Owned(CondExpr), LHS = Owned(LHSExpr), RHS = Owned(RHSExpr); 5119 QualType result = CheckConditionalOperands(Cond, LHS, RHS, 5120 VK, OK, QuestionLoc); 5121 if (result.isNull() || Cond.isInvalid() || LHS.isInvalid() || 5122 RHS.isInvalid()) 5123 return ExprError(); 5124 5125 DiagnoseConditionalPrecedence(*this, QuestionLoc, Cond.get(), LHS.get(), 5126 RHS.get()); 5127 5128 if (!commonExpr) 5129 return Owned(new (Context) ConditionalOperator(Cond.take(), QuestionLoc, 5130 LHS.take(), ColonLoc, 5131 RHS.take(), result, VK, OK)); 5132 5133 return Owned(new (Context) 5134 BinaryConditionalOperator(commonExpr, opaqueValue, Cond.take(), LHS.take(), 5135 RHS.take(), QuestionLoc, ColonLoc, result, VK, 5136 OK)); 5137} 5138 5139// checkPointerTypesForAssignment - This is a very tricky routine (despite 5140// being closely modeled after the C99 spec:-). The odd characteristic of this 5141// routine is it effectively iqnores the qualifiers on the top level pointee. 5142// This circumvents the usual type rules specified in 6.2.7p1 & 6.7.5.[1-3]. 5143// FIXME: add a couple examples in this comment. 5144static Sema::AssignConvertType 5145checkPointerTypesForAssignment(Sema &S, QualType LHSType, QualType RHSType) { 5146 assert(LHSType.isCanonical() && "LHS not canonicalized!"); 5147 assert(RHSType.isCanonical() && "RHS not canonicalized!"); 5148 5149 // get the "pointed to" type (ignoring qualifiers at the top level) 5150 const Type *lhptee, *rhptee; 5151 Qualifiers lhq, rhq; 5152 llvm::tie(lhptee, lhq) = cast<PointerType>(LHSType)->getPointeeType().split(); 5153 llvm::tie(rhptee, rhq) = cast<PointerType>(RHSType)->getPointeeType().split(); 5154 5155 Sema::AssignConvertType ConvTy = Sema::Compatible; 5156 5157 // C99 6.5.16.1p1: This following citation is common to constraints 5158 // 3 & 4 (below). ...and the type *pointed to* by the left has all the 5159 // qualifiers of the type *pointed to* by the right; 5160 Qualifiers lq; 5161 5162 // As a special case, 'non-__weak A *' -> 'non-__weak const *' is okay. 5163 if (lhq.getObjCLifetime() != rhq.getObjCLifetime() && 5164 lhq.compatiblyIncludesObjCLifetime(rhq)) { 5165 // Ignore lifetime for further calculation. 5166 lhq.removeObjCLifetime(); 5167 rhq.removeObjCLifetime(); 5168 } 5169 5170 if (!lhq.compatiblyIncludes(rhq)) { 5171 // Treat address-space mismatches as fatal. TODO: address subspaces 5172 if (lhq.getAddressSpace() != rhq.getAddressSpace()) 5173 ConvTy = Sema::IncompatiblePointerDiscardsQualifiers; 5174 5175 // It's okay to add or remove GC or lifetime qualifiers when converting to 5176 // and from void*. 5177 else if (lhq.withoutObjCGCAttr().withoutObjCLifetime() 5178 .compatiblyIncludes( 5179 rhq.withoutObjCGCAttr().withoutObjCLifetime()) 5180 && (lhptee->isVoidType() || rhptee->isVoidType())) 5181 ; // keep old 5182 5183 // Treat lifetime mismatches as fatal. 5184 else if (lhq.getObjCLifetime() != rhq.getObjCLifetime()) 5185 ConvTy = Sema::IncompatiblePointerDiscardsQualifiers; 5186 5187 // For GCC compatibility, other qualifier mismatches are treated 5188 // as still compatible in C. 5189 else ConvTy = Sema::CompatiblePointerDiscardsQualifiers; 5190 } 5191 5192 // C99 6.5.16.1p1 (constraint 4): If one operand is a pointer to an object or 5193 // incomplete type and the other is a pointer to a qualified or unqualified 5194 // version of void... 5195 if (lhptee->isVoidType()) { 5196 if (rhptee->isIncompleteOrObjectType()) 5197 return ConvTy; 5198 5199 // As an extension, we allow cast to/from void* to function pointer. 5200 assert(rhptee->isFunctionType()); 5201 return Sema::FunctionVoidPointer; 5202 } 5203 5204 if (rhptee->isVoidType()) { 5205 if (lhptee->isIncompleteOrObjectType()) 5206 return ConvTy; 5207 5208 // As an extension, we allow cast to/from void* to function pointer. 5209 assert(lhptee->isFunctionType()); 5210 return Sema::FunctionVoidPointer; 5211 } 5212 5213 // C99 6.5.16.1p1 (constraint 3): both operands are pointers to qualified or 5214 // unqualified versions of compatible types, ... 5215 QualType ltrans = QualType(lhptee, 0), rtrans = QualType(rhptee, 0); 5216 if (!S.Context.typesAreCompatible(ltrans, rtrans)) { 5217 // Check if the pointee types are compatible ignoring the sign. 5218 // We explicitly check for char so that we catch "char" vs 5219 // "unsigned char" on systems where "char" is unsigned. 5220 if (lhptee->isCharType()) 5221 ltrans = S.Context.UnsignedCharTy; 5222 else if (lhptee->hasSignedIntegerRepresentation()) 5223 ltrans = S.Context.getCorrespondingUnsignedType(ltrans); 5224 5225 if (rhptee->isCharType()) 5226 rtrans = S.Context.UnsignedCharTy; 5227 else if (rhptee->hasSignedIntegerRepresentation()) 5228 rtrans = S.Context.getCorrespondingUnsignedType(rtrans); 5229 5230 if (ltrans == rtrans) { 5231 // Types are compatible ignoring the sign. Qualifier incompatibility 5232 // takes priority over sign incompatibility because the sign 5233 // warning can be disabled. 5234 if (ConvTy != Sema::Compatible) 5235 return ConvTy; 5236 5237 return Sema::IncompatiblePointerSign; 5238 } 5239 5240 // If we are a multi-level pointer, it's possible that our issue is simply 5241 // one of qualification - e.g. char ** -> const char ** is not allowed. If 5242 // the eventual target type is the same and the pointers have the same 5243 // level of indirection, this must be the issue. 5244 if (isa<PointerType>(lhptee) && isa<PointerType>(rhptee)) { 5245 do { 5246 lhptee = cast<PointerType>(lhptee)->getPointeeType().getTypePtr(); 5247 rhptee = cast<PointerType>(rhptee)->getPointeeType().getTypePtr(); 5248 } while (isa<PointerType>(lhptee) && isa<PointerType>(rhptee)); 5249 5250 if (lhptee == rhptee) 5251 return Sema::IncompatibleNestedPointerQualifiers; 5252 } 5253 5254 // General pointer incompatibility takes priority over qualifiers. 5255 return Sema::IncompatiblePointer; 5256 } 5257 if (!S.getLangOpts().CPlusPlus && 5258 S.IsNoReturnConversion(ltrans, rtrans, ltrans)) 5259 return Sema::IncompatiblePointer; 5260 return ConvTy; 5261} 5262 5263/// checkBlockPointerTypesForAssignment - This routine determines whether two 5264/// block pointer types are compatible or whether a block and normal pointer 5265/// are compatible. It is more restrict than comparing two function pointer 5266// types. 5267static Sema::AssignConvertType 5268checkBlockPointerTypesForAssignment(Sema &S, QualType LHSType, 5269 QualType RHSType) { 5270 assert(LHSType.isCanonical() && "LHS not canonicalized!"); 5271 assert(RHSType.isCanonical() && "RHS not canonicalized!"); 5272 5273 QualType lhptee, rhptee; 5274 5275 // get the "pointed to" type (ignoring qualifiers at the top level) 5276 lhptee = cast<BlockPointerType>(LHSType)->getPointeeType(); 5277 rhptee = cast<BlockPointerType>(RHSType)->getPointeeType(); 5278 5279 // In C++, the types have to match exactly. 5280 if (S.getLangOpts().CPlusPlus) 5281 return Sema::IncompatibleBlockPointer; 5282 5283 Sema::AssignConvertType ConvTy = Sema::Compatible; 5284 5285 // For blocks we enforce that qualifiers are identical. 5286 if (lhptee.getLocalQualifiers() != rhptee.getLocalQualifiers()) 5287 ConvTy = Sema::CompatiblePointerDiscardsQualifiers; 5288 5289 if (!S.Context.typesAreBlockPointerCompatible(LHSType, RHSType)) 5290 return Sema::IncompatibleBlockPointer; 5291 5292 return ConvTy; 5293} 5294 5295/// checkObjCPointerTypesForAssignment - Compares two objective-c pointer types 5296/// for assignment compatibility. 5297static Sema::AssignConvertType 5298checkObjCPointerTypesForAssignment(Sema &S, QualType LHSType, 5299 QualType RHSType) { 5300 assert(LHSType.isCanonical() && "LHS was not canonicalized!"); 5301 assert(RHSType.isCanonical() && "RHS was not canonicalized!"); 5302 5303 if (LHSType->isObjCBuiltinType()) { 5304 // Class is not compatible with ObjC object pointers. 5305 if (LHSType->isObjCClassType() && !RHSType->isObjCBuiltinType() && 5306 !RHSType->isObjCQualifiedClassType()) 5307 return Sema::IncompatiblePointer; 5308 return Sema::Compatible; 5309 } 5310 if (RHSType->isObjCBuiltinType()) { 5311 if (RHSType->isObjCClassType() && !LHSType->isObjCBuiltinType() && 5312 !LHSType->isObjCQualifiedClassType()) 5313 return Sema::IncompatiblePointer; 5314 return Sema::Compatible; 5315 } 5316 QualType lhptee = LHSType->getAs<ObjCObjectPointerType>()->getPointeeType(); 5317 QualType rhptee = RHSType->getAs<ObjCObjectPointerType>()->getPointeeType(); 5318 5319 if (!lhptee.isAtLeastAsQualifiedAs(rhptee) && 5320 // make an exception for id<P> 5321 !LHSType->isObjCQualifiedIdType()) 5322 return Sema::CompatiblePointerDiscardsQualifiers; 5323 5324 if (S.Context.typesAreCompatible(LHSType, RHSType)) 5325 return Sema::Compatible; 5326 if (LHSType->isObjCQualifiedIdType() || RHSType->isObjCQualifiedIdType()) 5327 return Sema::IncompatibleObjCQualifiedId; 5328 return Sema::IncompatiblePointer; 5329} 5330 5331Sema::AssignConvertType 5332Sema::CheckAssignmentConstraints(SourceLocation Loc, 5333 QualType LHSType, QualType RHSType) { 5334 // Fake up an opaque expression. We don't actually care about what 5335 // cast operations are required, so if CheckAssignmentConstraints 5336 // adds casts to this they'll be wasted, but fortunately that doesn't 5337 // usually happen on valid code. 5338 OpaqueValueExpr RHSExpr(Loc, RHSType, VK_RValue); 5339 ExprResult RHSPtr = &RHSExpr; 5340 CastKind K = CK_Invalid; 5341 5342 return CheckAssignmentConstraints(LHSType, RHSPtr, K); 5343} 5344 5345/// CheckAssignmentConstraints (C99 6.5.16) - This routine currently 5346/// has code to accommodate several GCC extensions when type checking 5347/// pointers. Here are some objectionable examples that GCC considers warnings: 5348/// 5349/// int a, *pint; 5350/// short *pshort; 5351/// struct foo *pfoo; 5352/// 5353/// pint = pshort; // warning: assignment from incompatible pointer type 5354/// a = pint; // warning: assignment makes integer from pointer without a cast 5355/// pint = a; // warning: assignment makes pointer from integer without a cast 5356/// pint = pfoo; // warning: assignment from incompatible pointer type 5357/// 5358/// As a result, the code for dealing with pointers is more complex than the 5359/// C99 spec dictates. 5360/// 5361/// Sets 'Kind' for any result kind except Incompatible. 5362Sema::AssignConvertType 5363Sema::CheckAssignmentConstraints(QualType LHSType, ExprResult &RHS, 5364 CastKind &Kind) { 5365 QualType RHSType = RHS.get()->getType(); 5366 QualType OrigLHSType = LHSType; 5367 5368 // Get canonical types. We're not formatting these types, just comparing 5369 // them. 5370 LHSType = Context.getCanonicalType(LHSType).getUnqualifiedType(); 5371 RHSType = Context.getCanonicalType(RHSType).getUnqualifiedType(); 5372 5373 5374 // Common case: no conversion required. 5375 if (LHSType == RHSType) { 5376 Kind = CK_NoOp; 5377 return Compatible; 5378 } 5379 5380 if (const AtomicType *AtomicTy = dyn_cast<AtomicType>(LHSType)) { 5381 if (AtomicTy->getValueType() == RHSType) { 5382 Kind = CK_NonAtomicToAtomic; 5383 return Compatible; 5384 } 5385 } 5386 5387 if (const AtomicType *AtomicTy = dyn_cast<AtomicType>(RHSType)) { 5388 if (AtomicTy->getValueType() == LHSType) { 5389 Kind = CK_AtomicToNonAtomic; 5390 return Compatible; 5391 } 5392 } 5393 5394 5395 // If the left-hand side is a reference type, then we are in a 5396 // (rare!) case where we've allowed the use of references in C, 5397 // e.g., as a parameter type in a built-in function. In this case, 5398 // just make sure that the type referenced is compatible with the 5399 // right-hand side type. The caller is responsible for adjusting 5400 // LHSType so that the resulting expression does not have reference 5401 // type. 5402 if (const ReferenceType *LHSTypeRef = LHSType->getAs<ReferenceType>()) { 5403 if (Context.typesAreCompatible(LHSTypeRef->getPointeeType(), RHSType)) { 5404 Kind = CK_LValueBitCast; 5405 return Compatible; 5406 } 5407 return Incompatible; 5408 } 5409 5410 // Allow scalar to ExtVector assignments, and assignments of an ExtVector type 5411 // to the same ExtVector type. 5412 if (LHSType->isExtVectorType()) { 5413 if (RHSType->isExtVectorType()) 5414 return Incompatible; 5415 if (RHSType->isArithmeticType()) { 5416 // CK_VectorSplat does T -> vector T, so first cast to the 5417 // element type. 5418 QualType elType = cast<ExtVectorType>(LHSType)->getElementType(); 5419 if (elType != RHSType) { 5420 Kind = PrepareScalarCast(RHS, elType); 5421 RHS = ImpCastExprToType(RHS.take(), elType, Kind); 5422 } 5423 Kind = CK_VectorSplat; 5424 return Compatible; 5425 } 5426 } 5427 5428 // Conversions to or from vector type. 5429 if (LHSType->isVectorType() || RHSType->isVectorType()) { 5430 if (LHSType->isVectorType() && RHSType->isVectorType()) { 5431 // Allow assignments of an AltiVec vector type to an equivalent GCC 5432 // vector type and vice versa 5433 if (Context.areCompatibleVectorTypes(LHSType, RHSType)) { 5434 Kind = CK_BitCast; 5435 return Compatible; 5436 } 5437 5438 // If we are allowing lax vector conversions, and LHS and RHS are both 5439 // vectors, the total size only needs to be the same. This is a bitcast; 5440 // no bits are changed but the result type is different. 5441 if (getLangOpts().LaxVectorConversions && 5442 (Context.getTypeSize(LHSType) == Context.getTypeSize(RHSType))) { 5443 Kind = CK_BitCast; 5444 return IncompatibleVectors; 5445 } 5446 } 5447 return Incompatible; 5448 } 5449 5450 // Arithmetic conversions. 5451 if (LHSType->isArithmeticType() && RHSType->isArithmeticType() && 5452 !(getLangOpts().CPlusPlus && LHSType->isEnumeralType())) { 5453 Kind = PrepareScalarCast(RHS, LHSType); 5454 return Compatible; 5455 } 5456 5457 // Conversions to normal pointers. 5458 if (const PointerType *LHSPointer = dyn_cast<PointerType>(LHSType)) { 5459 // U* -> T* 5460 if (isa<PointerType>(RHSType)) { 5461 Kind = CK_BitCast; 5462 return checkPointerTypesForAssignment(*this, LHSType, RHSType); 5463 } 5464 5465 // int -> T* 5466 if (RHSType->isIntegerType()) { 5467 Kind = CK_IntegralToPointer; // FIXME: null? 5468 return IntToPointer; 5469 } 5470 5471 // C pointers are not compatible with ObjC object pointers, 5472 // with two exceptions: 5473 if (isa<ObjCObjectPointerType>(RHSType)) { 5474 // - conversions to void* 5475 if (LHSPointer->getPointeeType()->isVoidType()) { 5476 Kind = CK_BitCast; 5477 return Compatible; 5478 } 5479 5480 // - conversions from 'Class' to the redefinition type 5481 if (RHSType->isObjCClassType() && 5482 Context.hasSameType(LHSType, 5483 Context.getObjCClassRedefinitionType())) { 5484 Kind = CK_BitCast; 5485 return Compatible; 5486 } 5487 5488 Kind = CK_BitCast; 5489 return IncompatiblePointer; 5490 } 5491 5492 // U^ -> void* 5493 if (RHSType->getAs<BlockPointerType>()) { 5494 if (LHSPointer->getPointeeType()->isVoidType()) { 5495 Kind = CK_BitCast; 5496 return Compatible; 5497 } 5498 } 5499 5500 return Incompatible; 5501 } 5502 5503 // Conversions to block pointers. 5504 if (isa<BlockPointerType>(LHSType)) { 5505 // U^ -> T^ 5506 if (RHSType->isBlockPointerType()) { 5507 Kind = CK_BitCast; 5508 return checkBlockPointerTypesForAssignment(*this, LHSType, RHSType); 5509 } 5510 5511 // int or null -> T^ 5512 if (RHSType->isIntegerType()) { 5513 Kind = CK_IntegralToPointer; // FIXME: null 5514 return IntToBlockPointer; 5515 } 5516 5517 // id -> T^ 5518 if (getLangOpts().ObjC1 && RHSType->isObjCIdType()) { 5519 Kind = CK_AnyPointerToBlockPointerCast; 5520 return Compatible; 5521 } 5522 5523 // void* -> T^ 5524 if (const PointerType *RHSPT = RHSType->getAs<PointerType>()) 5525 if (RHSPT->getPointeeType()->isVoidType()) { 5526 Kind = CK_AnyPointerToBlockPointerCast; 5527 return Compatible; 5528 } 5529 5530 return Incompatible; 5531 } 5532 5533 // Conversions to Objective-C pointers. 5534 if (isa<ObjCObjectPointerType>(LHSType)) { 5535 // A* -> B* 5536 if (RHSType->isObjCObjectPointerType()) { 5537 Kind = CK_BitCast; 5538 Sema::AssignConvertType result = 5539 checkObjCPointerTypesForAssignment(*this, LHSType, RHSType); 5540 if (getLangOpts().ObjCAutoRefCount && 5541 result == Compatible && 5542 !CheckObjCARCUnavailableWeakConversion(OrigLHSType, RHSType)) 5543 result = IncompatibleObjCWeakRef; 5544 return result; 5545 } 5546 5547 // int or null -> A* 5548 if (RHSType->isIntegerType()) { 5549 Kind = CK_IntegralToPointer; // FIXME: null 5550 return IntToPointer; 5551 } 5552 5553 // In general, C pointers are not compatible with ObjC object pointers, 5554 // with two exceptions: 5555 if (isa<PointerType>(RHSType)) { 5556 Kind = CK_CPointerToObjCPointerCast; 5557 5558 // - conversions from 'void*' 5559 if (RHSType->isVoidPointerType()) { 5560 return Compatible; 5561 } 5562 5563 // - conversions to 'Class' from its redefinition type 5564 if (LHSType->isObjCClassType() && 5565 Context.hasSameType(RHSType, 5566 Context.getObjCClassRedefinitionType())) { 5567 return Compatible; 5568 } 5569 5570 return IncompatiblePointer; 5571 } 5572 5573 // T^ -> A* 5574 if (RHSType->isBlockPointerType()) { 5575 maybeExtendBlockObject(*this, RHS); 5576 Kind = CK_BlockPointerToObjCPointerCast; 5577 return Compatible; 5578 } 5579 5580 return Incompatible; 5581 } 5582 5583 // Conversions from pointers that are not covered by the above. 5584 if (isa<PointerType>(RHSType)) { 5585 // T* -> _Bool 5586 if (LHSType == Context.BoolTy) { 5587 Kind = CK_PointerToBoolean; 5588 return Compatible; 5589 } 5590 5591 // T* -> int 5592 if (LHSType->isIntegerType()) { 5593 Kind = CK_PointerToIntegral; 5594 return PointerToInt; 5595 } 5596 5597 return Incompatible; 5598 } 5599 5600 // Conversions from Objective-C pointers that are not covered by the above. 5601 if (isa<ObjCObjectPointerType>(RHSType)) { 5602 // T* -> _Bool 5603 if (LHSType == Context.BoolTy) { 5604 Kind = CK_PointerToBoolean; 5605 return Compatible; 5606 } 5607 5608 // T* -> int 5609 if (LHSType->isIntegerType()) { 5610 Kind = CK_PointerToIntegral; 5611 return PointerToInt; 5612 } 5613 5614 return Incompatible; 5615 } 5616 5617 // struct A -> struct B 5618 if (isa<TagType>(LHSType) && isa<TagType>(RHSType)) { 5619 if (Context.typesAreCompatible(LHSType, RHSType)) { 5620 Kind = CK_NoOp; 5621 return Compatible; 5622 } 5623 } 5624 5625 return Incompatible; 5626} 5627 5628/// \brief Constructs a transparent union from an expression that is 5629/// used to initialize the transparent union. 5630static void ConstructTransparentUnion(Sema &S, ASTContext &C, 5631 ExprResult &EResult, QualType UnionType, 5632 FieldDecl *Field) { 5633 // Build an initializer list that designates the appropriate member 5634 // of the transparent union. 5635 Expr *E = EResult.take(); 5636 InitListExpr *Initializer = new (C) InitListExpr(C, SourceLocation(), 5637 &E, 1, 5638 SourceLocation()); 5639 Initializer->setType(UnionType); 5640 Initializer->setInitializedFieldInUnion(Field); 5641 5642 // Build a compound literal constructing a value of the transparent 5643 // union type from this initializer list. 5644 TypeSourceInfo *unionTInfo = C.getTrivialTypeSourceInfo(UnionType); 5645 EResult = S.Owned( 5646 new (C) CompoundLiteralExpr(SourceLocation(), unionTInfo, UnionType, 5647 VK_RValue, Initializer, false)); 5648} 5649 5650Sema::AssignConvertType 5651Sema::CheckTransparentUnionArgumentConstraints(QualType ArgType, 5652 ExprResult &RHS) { 5653 QualType RHSType = RHS.get()->getType(); 5654 5655 // If the ArgType is a Union type, we want to handle a potential 5656 // transparent_union GCC extension. 5657 const RecordType *UT = ArgType->getAsUnionType(); 5658 if (!UT || !UT->getDecl()->hasAttr<TransparentUnionAttr>()) 5659 return Incompatible; 5660 5661 // The field to initialize within the transparent union. 5662 RecordDecl *UD = UT->getDecl(); 5663 FieldDecl *InitField = 0; 5664 // It's compatible if the expression matches any of the fields. 5665 for (RecordDecl::field_iterator it = UD->field_begin(), 5666 itend = UD->field_end(); 5667 it != itend; ++it) { 5668 if (it->getType()->isPointerType()) { 5669 // If the transparent union contains a pointer type, we allow: 5670 // 1) void pointer 5671 // 2) null pointer constant 5672 if (RHSType->isPointerType()) 5673 if (RHSType->castAs<PointerType>()->getPointeeType()->isVoidType()) { 5674 RHS = ImpCastExprToType(RHS.take(), it->getType(), CK_BitCast); 5675 InitField = *it; 5676 break; 5677 } 5678 5679 if (RHS.get()->isNullPointerConstant(Context, 5680 Expr::NPC_ValueDependentIsNull)) { 5681 RHS = ImpCastExprToType(RHS.take(), it->getType(), 5682 CK_NullToPointer); 5683 InitField = *it; 5684 break; 5685 } 5686 } 5687 5688 CastKind Kind = CK_Invalid; 5689 if (CheckAssignmentConstraints(it->getType(), RHS, Kind) 5690 == Compatible) { 5691 RHS = ImpCastExprToType(RHS.take(), it->getType(), Kind); 5692 InitField = *it; 5693 break; 5694 } 5695 } 5696 5697 if (!InitField) 5698 return Incompatible; 5699 5700 ConstructTransparentUnion(*this, Context, RHS, ArgType, InitField); 5701 return Compatible; 5702} 5703 5704Sema::AssignConvertType 5705Sema::CheckSingleAssignmentConstraints(QualType LHSType, ExprResult &RHS, 5706 bool Diagnose) { 5707 if (getLangOpts().CPlusPlus) { 5708 if (!LHSType->isRecordType() && !LHSType->isAtomicType()) { 5709 // C++ 5.17p3: If the left operand is not of class type, the 5710 // expression is implicitly converted (C++ 4) to the 5711 // cv-unqualified type of the left operand. 5712 ExprResult Res; 5713 if (Diagnose) { 5714 Res = PerformImplicitConversion(RHS.get(), LHSType.getUnqualifiedType(), 5715 AA_Assigning); 5716 } else { 5717 ImplicitConversionSequence ICS = 5718 TryImplicitConversion(RHS.get(), LHSType.getUnqualifiedType(), 5719 /*SuppressUserConversions=*/false, 5720 /*AllowExplicit=*/false, 5721 /*InOverloadResolution=*/false, 5722 /*CStyle=*/false, 5723 /*AllowObjCWritebackConversion=*/false); 5724 if (ICS.isFailure()) 5725 return Incompatible; 5726 Res = PerformImplicitConversion(RHS.get(), LHSType.getUnqualifiedType(), 5727 ICS, AA_Assigning); 5728 } 5729 if (Res.isInvalid()) 5730 return Incompatible; 5731 Sema::AssignConvertType result = Compatible; 5732 if (getLangOpts().ObjCAutoRefCount && 5733 !CheckObjCARCUnavailableWeakConversion(LHSType, 5734 RHS.get()->getType())) 5735 result = IncompatibleObjCWeakRef; 5736 RHS = move(Res); 5737 return result; 5738 } 5739 5740 // FIXME: Currently, we fall through and treat C++ classes like C 5741 // structures. 5742 // FIXME: We also fall through for atomics; not sure what should 5743 // happen there, though. 5744 } 5745 5746 // C99 6.5.16.1p1: the left operand is a pointer and the right is 5747 // a null pointer constant. 5748 if ((LHSType->isPointerType() || 5749 LHSType->isObjCObjectPointerType() || 5750 LHSType->isBlockPointerType()) 5751 && RHS.get()->isNullPointerConstant(Context, 5752 Expr::NPC_ValueDependentIsNull)) { 5753 RHS = ImpCastExprToType(RHS.take(), LHSType, CK_NullToPointer); 5754 return Compatible; 5755 } 5756 5757 // This check seems unnatural, however it is necessary to ensure the proper 5758 // conversion of functions/arrays. If the conversion were done for all 5759 // DeclExpr's (created by ActOnIdExpression), it would mess up the unary 5760 // expressions that suppress this implicit conversion (&, sizeof). 5761 // 5762 // Suppress this for references: C++ 8.5.3p5. 5763 if (!LHSType->isReferenceType()) { 5764 RHS = DefaultFunctionArrayLvalueConversion(RHS.take()); 5765 if (RHS.isInvalid()) 5766 return Incompatible; 5767 } 5768 5769 CastKind Kind = CK_Invalid; 5770 Sema::AssignConvertType result = 5771 CheckAssignmentConstraints(LHSType, RHS, Kind); 5772 5773 // C99 6.5.16.1p2: The value of the right operand is converted to the 5774 // type of the assignment expression. 5775 // CheckAssignmentConstraints allows the left-hand side to be a reference, 5776 // so that we can use references in built-in functions even in C. 5777 // The getNonReferenceType() call makes sure that the resulting expression 5778 // does not have reference type. 5779 if (result != Incompatible && RHS.get()->getType() != LHSType) 5780 RHS = ImpCastExprToType(RHS.take(), 5781 LHSType.getNonLValueExprType(Context), Kind); 5782 return result; 5783} 5784 5785QualType Sema::InvalidOperands(SourceLocation Loc, ExprResult &LHS, 5786 ExprResult &RHS) { 5787 Diag(Loc, diag::err_typecheck_invalid_operands) 5788 << LHS.get()->getType() << RHS.get()->getType() 5789 << LHS.get()->getSourceRange() << RHS.get()->getSourceRange(); 5790 return QualType(); 5791} 5792 5793QualType Sema::CheckVectorOperands(ExprResult &LHS, ExprResult &RHS, 5794 SourceLocation Loc, bool IsCompAssign) { 5795 if (!IsCompAssign) { 5796 LHS = DefaultFunctionArrayLvalueConversion(LHS.take()); 5797 if (LHS.isInvalid()) 5798 return QualType(); 5799 } 5800 RHS = DefaultFunctionArrayLvalueConversion(RHS.take()); 5801 if (RHS.isInvalid()) 5802 return QualType(); 5803 5804 // For conversion purposes, we ignore any qualifiers. 5805 // For example, "const float" and "float" are equivalent. 5806 QualType LHSType = 5807 Context.getCanonicalType(LHS.get()->getType()).getUnqualifiedType(); 5808 QualType RHSType = 5809 Context.getCanonicalType(RHS.get()->getType()).getUnqualifiedType(); 5810 5811 // If the vector types are identical, return. 5812 if (LHSType == RHSType) 5813 return LHSType; 5814 5815 // Handle the case of equivalent AltiVec and GCC vector types 5816 if (LHSType->isVectorType() && RHSType->isVectorType() && 5817 Context.areCompatibleVectorTypes(LHSType, RHSType)) { 5818 if (LHSType->isExtVectorType()) { 5819 RHS = ImpCastExprToType(RHS.take(), LHSType, CK_BitCast); 5820 return LHSType; 5821 } 5822 5823 if (!IsCompAssign) 5824 LHS = ImpCastExprToType(LHS.take(), RHSType, CK_BitCast); 5825 return RHSType; 5826 } 5827 5828 if (getLangOpts().LaxVectorConversions && 5829 Context.getTypeSize(LHSType) == Context.getTypeSize(RHSType)) { 5830 // If we are allowing lax vector conversions, and LHS and RHS are both 5831 // vectors, the total size only needs to be the same. This is a 5832 // bitcast; no bits are changed but the result type is different. 5833 // FIXME: Should we really be allowing this? 5834 RHS = ImpCastExprToType(RHS.take(), LHSType, CK_BitCast); 5835 return LHSType; 5836 } 5837 5838 // Canonicalize the ExtVector to the LHS, remember if we swapped so we can 5839 // swap back (so that we don't reverse the inputs to a subtract, for instance. 5840 bool swapped = false; 5841 if (RHSType->isExtVectorType() && !IsCompAssign) { 5842 swapped = true; 5843 std::swap(RHS, LHS); 5844 std::swap(RHSType, LHSType); 5845 } 5846 5847 // Handle the case of an ext vector and scalar. 5848 if (const ExtVectorType *LV = LHSType->getAs<ExtVectorType>()) { 5849 QualType EltTy = LV->getElementType(); 5850 if (EltTy->isIntegralType(Context) && RHSType->isIntegralType(Context)) { 5851 int order = Context.getIntegerTypeOrder(EltTy, RHSType); 5852 if (order > 0) 5853 RHS = ImpCastExprToType(RHS.take(), EltTy, CK_IntegralCast); 5854 if (order >= 0) { 5855 RHS = ImpCastExprToType(RHS.take(), LHSType, CK_VectorSplat); 5856 if (swapped) std::swap(RHS, LHS); 5857 return LHSType; 5858 } 5859 } 5860 if (EltTy->isRealFloatingType() && RHSType->isScalarType() && 5861 RHSType->isRealFloatingType()) { 5862 int order = Context.getFloatingTypeOrder(EltTy, RHSType); 5863 if (order > 0) 5864 RHS = ImpCastExprToType(RHS.take(), EltTy, CK_FloatingCast); 5865 if (order >= 0) { 5866 RHS = ImpCastExprToType(RHS.take(), LHSType, CK_VectorSplat); 5867 if (swapped) std::swap(RHS, LHS); 5868 return LHSType; 5869 } 5870 } 5871 } 5872 5873 // Vectors of different size or scalar and non-ext-vector are errors. 5874 if (swapped) std::swap(RHS, LHS); 5875 Diag(Loc, diag::err_typecheck_vector_not_convertable) 5876 << LHS.get()->getType() << RHS.get()->getType() 5877 << LHS.get()->getSourceRange() << RHS.get()->getSourceRange(); 5878 return QualType(); 5879} 5880 5881// checkArithmeticNull - Detect when a NULL constant is used improperly in an 5882// expression. These are mainly cases where the null pointer is used as an 5883// integer instead of a pointer. 5884static void checkArithmeticNull(Sema &S, ExprResult &LHS, ExprResult &RHS, 5885 SourceLocation Loc, bool IsCompare) { 5886 // The canonical way to check for a GNU null is with isNullPointerConstant, 5887 // but we use a bit of a hack here for speed; this is a relatively 5888 // hot path, and isNullPointerConstant is slow. 5889 bool LHSNull = isa<GNUNullExpr>(LHS.get()->IgnoreParenImpCasts()); 5890 bool RHSNull = isa<GNUNullExpr>(RHS.get()->IgnoreParenImpCasts()); 5891 5892 QualType NonNullType = LHSNull ? RHS.get()->getType() : LHS.get()->getType(); 5893 5894 // Avoid analyzing cases where the result will either be invalid (and 5895 // diagnosed as such) or entirely valid and not something to warn about. 5896 if ((!LHSNull && !RHSNull) || NonNullType->isBlockPointerType() || 5897 NonNullType->isMemberPointerType() || NonNullType->isFunctionType()) 5898 return; 5899 5900 // Comparison operations would not make sense with a null pointer no matter 5901 // what the other expression is. 5902 if (!IsCompare) { 5903 S.Diag(Loc, diag::warn_null_in_arithmetic_operation) 5904 << (LHSNull ? LHS.get()->getSourceRange() : SourceRange()) 5905 << (RHSNull ? RHS.get()->getSourceRange() : SourceRange()); 5906 return; 5907 } 5908 5909 // The rest of the operations only make sense with a null pointer 5910 // if the other expression is a pointer. 5911 if (LHSNull == RHSNull || NonNullType->isAnyPointerType() || 5912 NonNullType->canDecayToPointerType()) 5913 return; 5914 5915 S.Diag(Loc, diag::warn_null_in_comparison_operation) 5916 << LHSNull /* LHS is NULL */ << NonNullType 5917 << LHS.get()->getSourceRange() << RHS.get()->getSourceRange(); 5918} 5919 5920QualType Sema::CheckMultiplyDivideOperands(ExprResult &LHS, ExprResult &RHS, 5921 SourceLocation Loc, 5922 bool IsCompAssign, bool IsDiv) { 5923 checkArithmeticNull(*this, LHS, RHS, Loc, /*isCompare=*/false); 5924 5925 if (LHS.get()->getType()->isVectorType() || 5926 RHS.get()->getType()->isVectorType()) 5927 return CheckVectorOperands(LHS, RHS, Loc, IsCompAssign); 5928 5929 QualType compType = UsualArithmeticConversions(LHS, RHS, IsCompAssign); 5930 if (LHS.isInvalid() || RHS.isInvalid()) 5931 return QualType(); 5932 5933 5934 if (!LHS.get()->getType()->isArithmeticType() || 5935 !RHS.get()->getType()->isArithmeticType()) { 5936 if (IsCompAssign && 5937 LHS.get()->getType()->isAtomicType() && 5938 RHS.get()->getType()->isArithmeticType()) 5939 return compType; 5940 return InvalidOperands(Loc, LHS, RHS); 5941 } 5942 5943 // Check for division by zero. 5944 if (IsDiv && 5945 RHS.get()->isNullPointerConstant(Context, 5946 Expr::NPC_ValueDependentIsNotNull)) 5947 DiagRuntimeBehavior(Loc, RHS.get(), PDiag(diag::warn_division_by_zero) 5948 << RHS.get()->getSourceRange()); 5949 5950 return compType; 5951} 5952 5953QualType Sema::CheckRemainderOperands( 5954 ExprResult &LHS, ExprResult &RHS, SourceLocation Loc, bool IsCompAssign) { 5955 checkArithmeticNull(*this, LHS, RHS, Loc, /*isCompare=*/false); 5956 5957 if (LHS.get()->getType()->isVectorType() || 5958 RHS.get()->getType()->isVectorType()) { 5959 if (LHS.get()->getType()->hasIntegerRepresentation() && 5960 RHS.get()->getType()->hasIntegerRepresentation()) 5961 return CheckVectorOperands(LHS, RHS, Loc, IsCompAssign); 5962 return InvalidOperands(Loc, LHS, RHS); 5963 } 5964 5965 QualType compType = UsualArithmeticConversions(LHS, RHS, IsCompAssign); 5966 if (LHS.isInvalid() || RHS.isInvalid()) 5967 return QualType(); 5968 5969 if (!LHS.get()->getType()->isIntegerType() || 5970 !RHS.get()->getType()->isIntegerType()) 5971 return InvalidOperands(Loc, LHS, RHS); 5972 5973 // Check for remainder by zero. 5974 if (RHS.get()->isNullPointerConstant(Context, 5975 Expr::NPC_ValueDependentIsNotNull)) 5976 DiagRuntimeBehavior(Loc, RHS.get(), PDiag(diag::warn_remainder_by_zero) 5977 << RHS.get()->getSourceRange()); 5978 5979 return compType; 5980} 5981 5982/// \brief Diagnose invalid arithmetic on two void pointers. 5983static void diagnoseArithmeticOnTwoVoidPointers(Sema &S, SourceLocation Loc, 5984 Expr *LHSExpr, Expr *RHSExpr) { 5985 S.Diag(Loc, S.getLangOpts().CPlusPlus 5986 ? diag::err_typecheck_pointer_arith_void_type 5987 : diag::ext_gnu_void_ptr) 5988 << 1 /* two pointers */ << LHSExpr->getSourceRange() 5989 << RHSExpr->getSourceRange(); 5990} 5991 5992/// \brief Diagnose invalid arithmetic on a void pointer. 5993static void diagnoseArithmeticOnVoidPointer(Sema &S, SourceLocation Loc, 5994 Expr *Pointer) { 5995 S.Diag(Loc, S.getLangOpts().CPlusPlus 5996 ? diag::err_typecheck_pointer_arith_void_type 5997 : diag::ext_gnu_void_ptr) 5998 << 0 /* one pointer */ << Pointer->getSourceRange(); 5999} 6000 6001/// \brief Diagnose invalid arithmetic on two function pointers. 6002static void diagnoseArithmeticOnTwoFunctionPointers(Sema &S, SourceLocation Loc, 6003 Expr *LHS, Expr *RHS) { 6004 assert(LHS->getType()->isAnyPointerType()); 6005 assert(RHS->getType()->isAnyPointerType()); 6006 S.Diag(Loc, S.getLangOpts().CPlusPlus 6007 ? diag::err_typecheck_pointer_arith_function_type 6008 : diag::ext_gnu_ptr_func_arith) 6009 << 1 /* two pointers */ << LHS->getType()->getPointeeType() 6010 // We only show the second type if it differs from the first. 6011 << (unsigned)!S.Context.hasSameUnqualifiedType(LHS->getType(), 6012 RHS->getType()) 6013 << RHS->getType()->getPointeeType() 6014 << LHS->getSourceRange() << RHS->getSourceRange(); 6015} 6016 6017/// \brief Diagnose invalid arithmetic on a function pointer. 6018static void diagnoseArithmeticOnFunctionPointer(Sema &S, SourceLocation Loc, 6019 Expr *Pointer) { 6020 assert(Pointer->getType()->isAnyPointerType()); 6021 S.Diag(Loc, S.getLangOpts().CPlusPlus 6022 ? diag::err_typecheck_pointer_arith_function_type 6023 : diag::ext_gnu_ptr_func_arith) 6024 << 0 /* one pointer */ << Pointer->getType()->getPointeeType() 6025 << 0 /* one pointer, so only one type */ 6026 << Pointer->getSourceRange(); 6027} 6028 6029/// \brief Emit error if Operand is incomplete pointer type 6030/// 6031/// \returns True if pointer has incomplete type 6032static bool checkArithmeticIncompletePointerType(Sema &S, SourceLocation Loc, 6033 Expr *Operand) { 6034 if ((Operand->getType()->isPointerType() && 6035 !Operand->getType()->isDependentType()) || 6036 Operand->getType()->isObjCObjectPointerType()) { 6037 QualType PointeeTy = Operand->getType()->getPointeeType(); 6038 if (S.RequireCompleteType( 6039 Loc, PointeeTy, 6040 S.PDiag(diag::err_typecheck_arithmetic_incomplete_type) 6041 << PointeeTy << Operand->getSourceRange())) 6042 return true; 6043 } 6044 return false; 6045} 6046 6047/// \brief Check the validity of an arithmetic pointer operand. 6048/// 6049/// If the operand has pointer type, this code will check for pointer types 6050/// which are invalid in arithmetic operations. These will be diagnosed 6051/// appropriately, including whether or not the use is supported as an 6052/// extension. 6053/// 6054/// \returns True when the operand is valid to use (even if as an extension). 6055static bool checkArithmeticOpPointerOperand(Sema &S, SourceLocation Loc, 6056 Expr *Operand) { 6057 if (!Operand->getType()->isAnyPointerType()) return true; 6058 6059 QualType PointeeTy = Operand->getType()->getPointeeType(); 6060 if (PointeeTy->isVoidType()) { 6061 diagnoseArithmeticOnVoidPointer(S, Loc, Operand); 6062 return !S.getLangOpts().CPlusPlus; 6063 } 6064 if (PointeeTy->isFunctionType()) { 6065 diagnoseArithmeticOnFunctionPointer(S, Loc, Operand); 6066 return !S.getLangOpts().CPlusPlus; 6067 } 6068 6069 if (checkArithmeticIncompletePointerType(S, Loc, Operand)) return false; 6070 6071 return true; 6072} 6073 6074/// \brief Check the validity of a binary arithmetic operation w.r.t. pointer 6075/// operands. 6076/// 6077/// This routine will diagnose any invalid arithmetic on pointer operands much 6078/// like \see checkArithmeticOpPointerOperand. However, it has special logic 6079/// for emitting a single diagnostic even for operations where both LHS and RHS 6080/// are (potentially problematic) pointers. 6081/// 6082/// \returns True when the operand is valid to use (even if as an extension). 6083static bool checkArithmeticBinOpPointerOperands(Sema &S, SourceLocation Loc, 6084 Expr *LHSExpr, Expr *RHSExpr) { 6085 bool isLHSPointer = LHSExpr->getType()->isAnyPointerType(); 6086 bool isRHSPointer = RHSExpr->getType()->isAnyPointerType(); 6087 if (!isLHSPointer && !isRHSPointer) return true; 6088 6089 QualType LHSPointeeTy, RHSPointeeTy; 6090 if (isLHSPointer) LHSPointeeTy = LHSExpr->getType()->getPointeeType(); 6091 if (isRHSPointer) RHSPointeeTy = RHSExpr->getType()->getPointeeType(); 6092 6093 // Check for arithmetic on pointers to incomplete types. 6094 bool isLHSVoidPtr = isLHSPointer && LHSPointeeTy->isVoidType(); 6095 bool isRHSVoidPtr = isRHSPointer && RHSPointeeTy->isVoidType(); 6096 if (isLHSVoidPtr || isRHSVoidPtr) { 6097 if (!isRHSVoidPtr) diagnoseArithmeticOnVoidPointer(S, Loc, LHSExpr); 6098 else if (!isLHSVoidPtr) diagnoseArithmeticOnVoidPointer(S, Loc, RHSExpr); 6099 else diagnoseArithmeticOnTwoVoidPointers(S, Loc, LHSExpr, RHSExpr); 6100 6101 return !S.getLangOpts().CPlusPlus; 6102 } 6103 6104 bool isLHSFuncPtr = isLHSPointer && LHSPointeeTy->isFunctionType(); 6105 bool isRHSFuncPtr = isRHSPointer && RHSPointeeTy->isFunctionType(); 6106 if (isLHSFuncPtr || isRHSFuncPtr) { 6107 if (!isRHSFuncPtr) diagnoseArithmeticOnFunctionPointer(S, Loc, LHSExpr); 6108 else if (!isLHSFuncPtr) diagnoseArithmeticOnFunctionPointer(S, Loc, 6109 RHSExpr); 6110 else diagnoseArithmeticOnTwoFunctionPointers(S, Loc, LHSExpr, RHSExpr); 6111 6112 return !S.getLangOpts().CPlusPlus; 6113 } 6114 6115 if (checkArithmeticIncompletePointerType(S, Loc, LHSExpr)) return false; 6116 if (checkArithmeticIncompletePointerType(S, Loc, RHSExpr)) return false; 6117 6118 return true; 6119} 6120 6121/// \brief Check bad cases where we step over interface counts. 6122static bool checkArithmethicPointerOnNonFragileABI(Sema &S, 6123 SourceLocation OpLoc, 6124 Expr *Op) { 6125 assert(Op->getType()->isAnyPointerType()); 6126 QualType PointeeTy = Op->getType()->getPointeeType(); 6127 if (!PointeeTy->isObjCObjectType() || !S.LangOpts.ObjCNonFragileABI) 6128 return true; 6129 6130 S.Diag(OpLoc, diag::err_arithmetic_nonfragile_interface) 6131 << PointeeTy << Op->getSourceRange(); 6132 return false; 6133} 6134 6135/// diagnoseStringPlusInt - Emit a warning when adding an integer to a string 6136/// literal. 6137static void diagnoseStringPlusInt(Sema &Self, SourceLocation OpLoc, 6138 Expr *LHSExpr, Expr *RHSExpr) { 6139 StringLiteral* StrExpr = dyn_cast<StringLiteral>(LHSExpr->IgnoreImpCasts()); 6140 Expr* IndexExpr = RHSExpr; 6141 if (!StrExpr) { 6142 StrExpr = dyn_cast<StringLiteral>(RHSExpr->IgnoreImpCasts()); 6143 IndexExpr = LHSExpr; 6144 } 6145 6146 bool IsStringPlusInt = StrExpr && 6147 IndexExpr->getType()->isIntegralOrUnscopedEnumerationType(); 6148 if (!IsStringPlusInt) 6149 return; 6150 6151 llvm::APSInt index; 6152 if (IndexExpr->EvaluateAsInt(index, Self.getASTContext())) { 6153 unsigned StrLenWithNull = StrExpr->getLength() + 1; 6154 if (index.isNonNegative() && 6155 index <= llvm::APSInt(llvm::APInt(index.getBitWidth(), StrLenWithNull), 6156 index.isUnsigned())) 6157 return; 6158 } 6159 6160 SourceRange DiagRange(LHSExpr->getLocStart(), RHSExpr->getLocEnd()); 6161 Self.Diag(OpLoc, diag::warn_string_plus_int) 6162 << DiagRange << IndexExpr->IgnoreImpCasts()->getType(); 6163 6164 // Only print a fixit for "str" + int, not for int + "str". 6165 if (IndexExpr == RHSExpr) { 6166 SourceLocation EndLoc = Self.PP.getLocForEndOfToken(RHSExpr->getLocEnd()); 6167 Self.Diag(OpLoc, diag::note_string_plus_int_silence) 6168 << FixItHint::CreateInsertion(LHSExpr->getLocStart(), "&") 6169 << FixItHint::CreateReplacement(SourceRange(OpLoc), "[") 6170 << FixItHint::CreateInsertion(EndLoc, "]"); 6171 } else 6172 Self.Diag(OpLoc, diag::note_string_plus_int_silence); 6173} 6174 6175/// \brief Emit error when two pointers are incompatible. 6176static void diagnosePointerIncompatibility(Sema &S, SourceLocation Loc, 6177 Expr *LHSExpr, Expr *RHSExpr) { 6178 assert(LHSExpr->getType()->isAnyPointerType()); 6179 assert(RHSExpr->getType()->isAnyPointerType()); 6180 S.Diag(Loc, diag::err_typecheck_sub_ptr_compatible) 6181 << LHSExpr->getType() << RHSExpr->getType() << LHSExpr->getSourceRange() 6182 << RHSExpr->getSourceRange(); 6183} 6184 6185QualType Sema::CheckAdditionOperands( // C99 6.5.6 6186 ExprResult &LHS, ExprResult &RHS, SourceLocation Loc, unsigned Opc, 6187 QualType* CompLHSTy) { 6188 checkArithmeticNull(*this, LHS, RHS, Loc, /*isCompare=*/false); 6189 6190 if (LHS.get()->getType()->isVectorType() || 6191 RHS.get()->getType()->isVectorType()) { 6192 QualType compType = CheckVectorOperands(LHS, RHS, Loc, CompLHSTy); 6193 if (CompLHSTy) *CompLHSTy = compType; 6194 return compType; 6195 } 6196 6197 QualType compType = UsualArithmeticConversions(LHS, RHS, CompLHSTy); 6198 if (LHS.isInvalid() || RHS.isInvalid()) 6199 return QualType(); 6200 6201 // Diagnose "string literal" '+' int. 6202 if (Opc == BO_Add) 6203 diagnoseStringPlusInt(*this, Loc, LHS.get(), RHS.get()); 6204 6205 // handle the common case first (both operands are arithmetic). 6206 if (LHS.get()->getType()->isArithmeticType() && 6207 RHS.get()->getType()->isArithmeticType()) { 6208 if (CompLHSTy) *CompLHSTy = compType; 6209 return compType; 6210 } 6211 6212 if (LHS.get()->getType()->isAtomicType() && 6213 RHS.get()->getType()->isArithmeticType()) { 6214 *CompLHSTy = LHS.get()->getType(); 6215 return compType; 6216 } 6217 6218 // Put any potential pointer into PExp 6219 Expr* PExp = LHS.get(), *IExp = RHS.get(); 6220 if (IExp->getType()->isAnyPointerType()) 6221 std::swap(PExp, IExp); 6222 6223 if (!PExp->getType()->isAnyPointerType()) 6224 return InvalidOperands(Loc, LHS, RHS); 6225 6226 if (!IExp->getType()->isIntegerType()) 6227 return InvalidOperands(Loc, LHS, RHS); 6228 6229 if (!checkArithmeticOpPointerOperand(*this, Loc, PExp)) 6230 return QualType(); 6231 6232 // Diagnose bad cases where we step over interface counts. 6233 if (!checkArithmethicPointerOnNonFragileABI(*this, Loc, PExp)) 6234 return QualType(); 6235 6236 // Check array bounds for pointer arithemtic 6237 CheckArrayAccess(PExp, IExp); 6238 6239 if (CompLHSTy) { 6240 QualType LHSTy = Context.isPromotableBitField(LHS.get()); 6241 if (LHSTy.isNull()) { 6242 LHSTy = LHS.get()->getType(); 6243 if (LHSTy->isPromotableIntegerType()) 6244 LHSTy = Context.getPromotedIntegerType(LHSTy); 6245 } 6246 *CompLHSTy = LHSTy; 6247 } 6248 6249 return PExp->getType(); 6250} 6251 6252// C99 6.5.6 6253QualType Sema::CheckSubtractionOperands(ExprResult &LHS, ExprResult &RHS, 6254 SourceLocation Loc, 6255 QualType* CompLHSTy) { 6256 checkArithmeticNull(*this, LHS, RHS, Loc, /*isCompare=*/false); 6257 6258 if (LHS.get()->getType()->isVectorType() || 6259 RHS.get()->getType()->isVectorType()) { 6260 QualType compType = CheckVectorOperands(LHS, RHS, Loc, CompLHSTy); 6261 if (CompLHSTy) *CompLHSTy = compType; 6262 return compType; 6263 } 6264 6265 QualType compType = UsualArithmeticConversions(LHS, RHS, CompLHSTy); 6266 if (LHS.isInvalid() || RHS.isInvalid()) 6267 return QualType(); 6268 6269 // Enforce type constraints: C99 6.5.6p3. 6270 6271 // Handle the common case first (both operands are arithmetic). 6272 if (LHS.get()->getType()->isArithmeticType() && 6273 RHS.get()->getType()->isArithmeticType()) { 6274 if (CompLHSTy) *CompLHSTy = compType; 6275 return compType; 6276 } 6277 6278 if (LHS.get()->getType()->isAtomicType() && 6279 RHS.get()->getType()->isArithmeticType()) { 6280 *CompLHSTy = LHS.get()->getType(); 6281 return compType; 6282 } 6283 6284 // Either ptr - int or ptr - ptr. 6285 if (LHS.get()->getType()->isAnyPointerType()) { 6286 QualType lpointee = LHS.get()->getType()->getPointeeType(); 6287 6288 // Diagnose bad cases where we step over interface counts. 6289 if (!checkArithmethicPointerOnNonFragileABI(*this, Loc, LHS.get())) 6290 return QualType(); 6291 6292 // The result type of a pointer-int computation is the pointer type. 6293 if (RHS.get()->getType()->isIntegerType()) { 6294 if (!checkArithmeticOpPointerOperand(*this, Loc, LHS.get())) 6295 return QualType(); 6296 6297 // Check array bounds for pointer arithemtic 6298 CheckArrayAccess(LHS.get(), RHS.get(), /*ArraySubscriptExpr*/0, 6299 /*AllowOnePastEnd*/true, /*IndexNegated*/true); 6300 6301 if (CompLHSTy) *CompLHSTy = LHS.get()->getType(); 6302 return LHS.get()->getType(); 6303 } 6304 6305 // Handle pointer-pointer subtractions. 6306 if (const PointerType *RHSPTy 6307 = RHS.get()->getType()->getAs<PointerType>()) { 6308 QualType rpointee = RHSPTy->getPointeeType(); 6309 6310 if (getLangOpts().CPlusPlus) { 6311 // Pointee types must be the same: C++ [expr.add] 6312 if (!Context.hasSameUnqualifiedType(lpointee, rpointee)) { 6313 diagnosePointerIncompatibility(*this, Loc, LHS.get(), RHS.get()); 6314 } 6315 } else { 6316 // Pointee types must be compatible C99 6.5.6p3 6317 if (!Context.typesAreCompatible( 6318 Context.getCanonicalType(lpointee).getUnqualifiedType(), 6319 Context.getCanonicalType(rpointee).getUnqualifiedType())) { 6320 diagnosePointerIncompatibility(*this, Loc, LHS.get(), RHS.get()); 6321 return QualType(); 6322 } 6323 } 6324 6325 if (!checkArithmeticBinOpPointerOperands(*this, Loc, 6326 LHS.get(), RHS.get())) 6327 return QualType(); 6328 6329 if (CompLHSTy) *CompLHSTy = LHS.get()->getType(); 6330 return Context.getPointerDiffType(); 6331 } 6332 } 6333 6334 return InvalidOperands(Loc, LHS, RHS); 6335} 6336 6337static bool isScopedEnumerationType(QualType T) { 6338 if (const EnumType *ET = dyn_cast<EnumType>(T)) 6339 return ET->getDecl()->isScoped(); 6340 return false; 6341} 6342 6343static void DiagnoseBadShiftValues(Sema& S, ExprResult &LHS, ExprResult &RHS, 6344 SourceLocation Loc, unsigned Opc, 6345 QualType LHSType) { 6346 llvm::APSInt Right; 6347 // Check right/shifter operand 6348 if (RHS.get()->isValueDependent() || 6349 !RHS.get()->isIntegerConstantExpr(Right, S.Context)) 6350 return; 6351 6352 if (Right.isNegative()) { 6353 S.DiagRuntimeBehavior(Loc, RHS.get(), 6354 S.PDiag(diag::warn_shift_negative) 6355 << RHS.get()->getSourceRange()); 6356 return; 6357 } 6358 llvm::APInt LeftBits(Right.getBitWidth(), 6359 S.Context.getTypeSize(LHS.get()->getType())); 6360 if (Right.uge(LeftBits)) { 6361 S.DiagRuntimeBehavior(Loc, RHS.get(), 6362 S.PDiag(diag::warn_shift_gt_typewidth) 6363 << RHS.get()->getSourceRange()); 6364 return; 6365 } 6366 if (Opc != BO_Shl) 6367 return; 6368 6369 // When left shifting an ICE which is signed, we can check for overflow which 6370 // according to C++ has undefined behavior ([expr.shift] 5.8/2). Unsigned 6371 // integers have defined behavior modulo one more than the maximum value 6372 // representable in the result type, so never warn for those. 6373 llvm::APSInt Left; 6374 if (LHS.get()->isValueDependent() || 6375 !LHS.get()->isIntegerConstantExpr(Left, S.Context) || 6376 LHSType->hasUnsignedIntegerRepresentation()) 6377 return; 6378 llvm::APInt ResultBits = 6379 static_cast<llvm::APInt&>(Right) + Left.getMinSignedBits(); 6380 if (LeftBits.uge(ResultBits)) 6381 return; 6382 llvm::APSInt Result = Left.extend(ResultBits.getLimitedValue()); 6383 Result = Result.shl(Right); 6384 6385 // Print the bit representation of the signed integer as an unsigned 6386 // hexadecimal number. 6387 SmallString<40> HexResult; 6388 Result.toString(HexResult, 16, /*Signed =*/false, /*Literal =*/true); 6389 6390 // If we are only missing a sign bit, this is less likely to result in actual 6391 // bugs -- if the result is cast back to an unsigned type, it will have the 6392 // expected value. Thus we place this behind a different warning that can be 6393 // turned off separately if needed. 6394 if (LeftBits == ResultBits - 1) { 6395 S.Diag(Loc, diag::warn_shift_result_sets_sign_bit) 6396 << HexResult.str() << LHSType 6397 << LHS.get()->getSourceRange() << RHS.get()->getSourceRange(); 6398 return; 6399 } 6400 6401 S.Diag(Loc, diag::warn_shift_result_gt_typewidth) 6402 << HexResult.str() << Result.getMinSignedBits() << LHSType 6403 << Left.getBitWidth() << LHS.get()->getSourceRange() 6404 << RHS.get()->getSourceRange(); 6405} 6406 6407// C99 6.5.7 6408QualType Sema::CheckShiftOperands(ExprResult &LHS, ExprResult &RHS, 6409 SourceLocation Loc, unsigned Opc, 6410 bool IsCompAssign) { 6411 checkArithmeticNull(*this, LHS, RHS, Loc, /*isCompare=*/false); 6412 6413 // C99 6.5.7p2: Each of the operands shall have integer type. 6414 if (!LHS.get()->getType()->hasIntegerRepresentation() || 6415 !RHS.get()->getType()->hasIntegerRepresentation()) 6416 return InvalidOperands(Loc, LHS, RHS); 6417 6418 // C++0x: Don't allow scoped enums. FIXME: Use something better than 6419 // hasIntegerRepresentation() above instead of this. 6420 if (isScopedEnumerationType(LHS.get()->getType()) || 6421 isScopedEnumerationType(RHS.get()->getType())) { 6422 return InvalidOperands(Loc, LHS, RHS); 6423 } 6424 6425 // Vector shifts promote their scalar inputs to vector type. 6426 if (LHS.get()->getType()->isVectorType() || 6427 RHS.get()->getType()->isVectorType()) 6428 return CheckVectorOperands(LHS, RHS, Loc, IsCompAssign); 6429 6430 // Shifts don't perform usual arithmetic conversions, they just do integer 6431 // promotions on each operand. C99 6.5.7p3 6432 6433 // For the LHS, do usual unary conversions, but then reset them away 6434 // if this is a compound assignment. 6435 ExprResult OldLHS = LHS; 6436 LHS = UsualUnaryConversions(LHS.take()); 6437 if (LHS.isInvalid()) 6438 return QualType(); 6439 QualType LHSType = LHS.get()->getType(); 6440 if (IsCompAssign) LHS = OldLHS; 6441 6442 // The RHS is simpler. 6443 RHS = UsualUnaryConversions(RHS.take()); 6444 if (RHS.isInvalid()) 6445 return QualType(); 6446 6447 // Sanity-check shift operands 6448 DiagnoseBadShiftValues(*this, LHS, RHS, Loc, Opc, LHSType); 6449 6450 // "The type of the result is that of the promoted left operand." 6451 return LHSType; 6452} 6453 6454static bool IsWithinTemplateSpecialization(Decl *D) { 6455 if (DeclContext *DC = D->getDeclContext()) { 6456 if (isa<ClassTemplateSpecializationDecl>(DC)) 6457 return true; 6458 if (FunctionDecl *FD = dyn_cast<FunctionDecl>(DC)) 6459 return FD->isFunctionTemplateSpecialization(); 6460 } 6461 return false; 6462} 6463 6464/// If two different enums are compared, raise a warning. 6465static void checkEnumComparison(Sema &S, SourceLocation Loc, ExprResult &LHS, 6466 ExprResult &RHS) { 6467 QualType LHSStrippedType = LHS.get()->IgnoreParenImpCasts()->getType(); 6468 QualType RHSStrippedType = RHS.get()->IgnoreParenImpCasts()->getType(); 6469 6470 const EnumType *LHSEnumType = LHSStrippedType->getAs<EnumType>(); 6471 if (!LHSEnumType) 6472 return; 6473 const EnumType *RHSEnumType = RHSStrippedType->getAs<EnumType>(); 6474 if (!RHSEnumType) 6475 return; 6476 6477 // Ignore anonymous enums. 6478 if (!LHSEnumType->getDecl()->getIdentifier()) 6479 return; 6480 if (!RHSEnumType->getDecl()->getIdentifier()) 6481 return; 6482 6483 if (S.Context.hasSameUnqualifiedType(LHSStrippedType, RHSStrippedType)) 6484 return; 6485 6486 S.Diag(Loc, diag::warn_comparison_of_mixed_enum_types) 6487 << LHSStrippedType << RHSStrippedType 6488 << LHS.get()->getSourceRange() << RHS.get()->getSourceRange(); 6489} 6490 6491/// \brief Diagnose bad pointer comparisons. 6492static void diagnoseDistinctPointerComparison(Sema &S, SourceLocation Loc, 6493 ExprResult &LHS, ExprResult &RHS, 6494 bool IsError) { 6495 S.Diag(Loc, IsError ? diag::err_typecheck_comparison_of_distinct_pointers 6496 : diag::ext_typecheck_comparison_of_distinct_pointers) 6497 << LHS.get()->getType() << RHS.get()->getType() 6498 << LHS.get()->getSourceRange() << RHS.get()->getSourceRange(); 6499} 6500 6501/// \brief Returns false if the pointers are converted to a composite type, 6502/// true otherwise. 6503static bool convertPointersToCompositeType(Sema &S, SourceLocation Loc, 6504 ExprResult &LHS, ExprResult &RHS) { 6505 // C++ [expr.rel]p2: 6506 // [...] Pointer conversions (4.10) and qualification 6507 // conversions (4.4) are performed on pointer operands (or on 6508 // a pointer operand and a null pointer constant) to bring 6509 // them to their composite pointer type. [...] 6510 // 6511 // C++ [expr.eq]p1 uses the same notion for (in)equality 6512 // comparisons of pointers. 6513 6514 // C++ [expr.eq]p2: 6515 // In addition, pointers to members can be compared, or a pointer to 6516 // member and a null pointer constant. Pointer to member conversions 6517 // (4.11) and qualification conversions (4.4) are performed to bring 6518 // them to a common type. If one operand is a null pointer constant, 6519 // the common type is the type of the other operand. Otherwise, the 6520 // common type is a pointer to member type similar (4.4) to the type 6521 // of one of the operands, with a cv-qualification signature (4.4) 6522 // that is the union of the cv-qualification signatures of the operand 6523 // types. 6524 6525 QualType LHSType = LHS.get()->getType(); 6526 QualType RHSType = RHS.get()->getType(); 6527 assert((LHSType->isPointerType() && RHSType->isPointerType()) || 6528 (LHSType->isMemberPointerType() && RHSType->isMemberPointerType())); 6529 6530 bool NonStandardCompositeType = false; 6531 bool *BoolPtr = S.isSFINAEContext() ? 0 : &NonStandardCompositeType; 6532 QualType T = S.FindCompositePointerType(Loc, LHS, RHS, BoolPtr); 6533 if (T.isNull()) { 6534 diagnoseDistinctPointerComparison(S, Loc, LHS, RHS, /*isError*/true); 6535 return true; 6536 } 6537 6538 if (NonStandardCompositeType) 6539 S.Diag(Loc, diag::ext_typecheck_comparison_of_distinct_pointers_nonstandard) 6540 << LHSType << RHSType << T << LHS.get()->getSourceRange() 6541 << RHS.get()->getSourceRange(); 6542 6543 LHS = S.ImpCastExprToType(LHS.take(), T, CK_BitCast); 6544 RHS = S.ImpCastExprToType(RHS.take(), T, CK_BitCast); 6545 return false; 6546} 6547 6548static void diagnoseFunctionPointerToVoidComparison(Sema &S, SourceLocation Loc, 6549 ExprResult &LHS, 6550 ExprResult &RHS, 6551 bool IsError) { 6552 S.Diag(Loc, IsError ? diag::err_typecheck_comparison_of_fptr_to_void 6553 : diag::ext_typecheck_comparison_of_fptr_to_void) 6554 << LHS.get()->getType() << RHS.get()->getType() 6555 << LHS.get()->getSourceRange() << RHS.get()->getSourceRange(); 6556} 6557 6558// C99 6.5.8, C++ [expr.rel] 6559QualType Sema::CheckCompareOperands(ExprResult &LHS, ExprResult &RHS, 6560 SourceLocation Loc, unsigned OpaqueOpc, 6561 bool IsRelational) { 6562 checkArithmeticNull(*this, LHS, RHS, Loc, /*isCompare=*/true); 6563 6564 BinaryOperatorKind Opc = (BinaryOperatorKind) OpaqueOpc; 6565 6566 // Handle vector comparisons separately. 6567 if (LHS.get()->getType()->isVectorType() || 6568 RHS.get()->getType()->isVectorType()) 6569 return CheckVectorCompareOperands(LHS, RHS, Loc, IsRelational); 6570 6571 QualType LHSType = LHS.get()->getType(); 6572 QualType RHSType = RHS.get()->getType(); 6573 6574 Expr *LHSStripped = LHS.get()->IgnoreParenImpCasts(); 6575 Expr *RHSStripped = RHS.get()->IgnoreParenImpCasts(); 6576 6577 checkEnumComparison(*this, Loc, LHS, RHS); 6578 6579 if (!LHSType->hasFloatingRepresentation() && 6580 !(LHSType->isBlockPointerType() && IsRelational) && 6581 !LHS.get()->getLocStart().isMacroID() && 6582 !RHS.get()->getLocStart().isMacroID()) { 6583 // For non-floating point types, check for self-comparisons of the form 6584 // x == x, x != x, x < x, etc. These always evaluate to a constant, and 6585 // often indicate logic errors in the program. 6586 // 6587 // NOTE: Don't warn about comparison expressions resulting from macro 6588 // expansion. Also don't warn about comparisons which are only self 6589 // comparisons within a template specialization. The warnings should catch 6590 // obvious cases in the definition of the template anyways. The idea is to 6591 // warn when the typed comparison operator will always evaluate to the same 6592 // result. 6593 if (DeclRefExpr* DRL = dyn_cast<DeclRefExpr>(LHSStripped)) { 6594 if (DeclRefExpr* DRR = dyn_cast<DeclRefExpr>(RHSStripped)) { 6595 if (DRL->getDecl() == DRR->getDecl() && 6596 !IsWithinTemplateSpecialization(DRL->getDecl())) { 6597 DiagRuntimeBehavior(Loc, 0, PDiag(diag::warn_comparison_always) 6598 << 0 // self- 6599 << (Opc == BO_EQ 6600 || Opc == BO_LE 6601 || Opc == BO_GE)); 6602 } else if (LHSType->isArrayType() && RHSType->isArrayType() && 6603 !DRL->getDecl()->getType()->isReferenceType() && 6604 !DRR->getDecl()->getType()->isReferenceType()) { 6605 // what is it always going to eval to? 6606 char always_evals_to; 6607 switch(Opc) { 6608 case BO_EQ: // e.g. array1 == array2 6609 always_evals_to = 0; // false 6610 break; 6611 case BO_NE: // e.g. array1 != array2 6612 always_evals_to = 1; // true 6613 break; 6614 default: 6615 // best we can say is 'a constant' 6616 always_evals_to = 2; // e.g. array1 <= array2 6617 break; 6618 } 6619 DiagRuntimeBehavior(Loc, 0, PDiag(diag::warn_comparison_always) 6620 << 1 // array 6621 << always_evals_to); 6622 } 6623 } 6624 } 6625 6626 if (isa<CastExpr>(LHSStripped)) 6627 LHSStripped = LHSStripped->IgnoreParenCasts(); 6628 if (isa<CastExpr>(RHSStripped)) 6629 RHSStripped = RHSStripped->IgnoreParenCasts(); 6630 6631 // Warn about comparisons against a string constant (unless the other 6632 // operand is null), the user probably wants strcmp. 6633 Expr *literalString = 0; 6634 Expr *literalStringStripped = 0; 6635 if ((isa<StringLiteral>(LHSStripped) || isa<ObjCEncodeExpr>(LHSStripped)) && 6636 !RHSStripped->isNullPointerConstant(Context, 6637 Expr::NPC_ValueDependentIsNull)) { 6638 literalString = LHS.get(); 6639 literalStringStripped = LHSStripped; 6640 } else if ((isa<StringLiteral>(RHSStripped) || 6641 isa<ObjCEncodeExpr>(RHSStripped)) && 6642 !LHSStripped->isNullPointerConstant(Context, 6643 Expr::NPC_ValueDependentIsNull)) { 6644 literalString = RHS.get(); 6645 literalStringStripped = RHSStripped; 6646 } 6647 6648 if (literalString) { 6649 std::string resultComparison; 6650 switch (Opc) { 6651 case BO_LT: resultComparison = ") < 0"; break; 6652 case BO_GT: resultComparison = ") > 0"; break; 6653 case BO_LE: resultComparison = ") <= 0"; break; 6654 case BO_GE: resultComparison = ") >= 0"; break; 6655 case BO_EQ: resultComparison = ") == 0"; break; 6656 case BO_NE: resultComparison = ") != 0"; break; 6657 default: llvm_unreachable("Invalid comparison operator"); 6658 } 6659 6660 DiagRuntimeBehavior(Loc, 0, 6661 PDiag(diag::warn_stringcompare) 6662 << isa<ObjCEncodeExpr>(literalStringStripped) 6663 << literalString->getSourceRange()); 6664 } 6665 } 6666 6667 // C99 6.5.8p3 / C99 6.5.9p4 6668 if (LHS.get()->getType()->isArithmeticType() && 6669 RHS.get()->getType()->isArithmeticType()) { 6670 UsualArithmeticConversions(LHS, RHS); 6671 if (LHS.isInvalid() || RHS.isInvalid()) 6672 return QualType(); 6673 } 6674 else { 6675 LHS = UsualUnaryConversions(LHS.take()); 6676 if (LHS.isInvalid()) 6677 return QualType(); 6678 6679 RHS = UsualUnaryConversions(RHS.take()); 6680 if (RHS.isInvalid()) 6681 return QualType(); 6682 } 6683 6684 LHSType = LHS.get()->getType(); 6685 RHSType = RHS.get()->getType(); 6686 6687 // The result of comparisons is 'bool' in C++, 'int' in C. 6688 QualType ResultTy = Context.getLogicalOperationType(); 6689 6690 if (IsRelational) { 6691 if (LHSType->isRealType() && RHSType->isRealType()) 6692 return ResultTy; 6693 } else { 6694 // Check for comparisons of floating point operands using != and ==. 6695 if (LHSType->hasFloatingRepresentation()) 6696 CheckFloatComparison(Loc, LHS.get(), RHS.get()); 6697 6698 if (LHSType->isArithmeticType() && RHSType->isArithmeticType()) 6699 return ResultTy; 6700 } 6701 6702 bool LHSIsNull = LHS.get()->isNullPointerConstant(Context, 6703 Expr::NPC_ValueDependentIsNull); 6704 bool RHSIsNull = RHS.get()->isNullPointerConstant(Context, 6705 Expr::NPC_ValueDependentIsNull); 6706 6707 // All of the following pointer-related warnings are GCC extensions, except 6708 // when handling null pointer constants. 6709 if (LHSType->isPointerType() && RHSType->isPointerType()) { // C99 6.5.8p2 6710 QualType LCanPointeeTy = 6711 LHSType->castAs<PointerType>()->getPointeeType().getCanonicalType(); 6712 QualType RCanPointeeTy = 6713 RHSType->castAs<PointerType>()->getPointeeType().getCanonicalType(); 6714 6715 if (getLangOpts().CPlusPlus) { 6716 if (LCanPointeeTy == RCanPointeeTy) 6717 return ResultTy; 6718 if (!IsRelational && 6719 (LCanPointeeTy->isVoidType() || RCanPointeeTy->isVoidType())) { 6720 // Valid unless comparison between non-null pointer and function pointer 6721 // This is a gcc extension compatibility comparison. 6722 // In a SFINAE context, we treat this as a hard error to maintain 6723 // conformance with the C++ standard. 6724 if ((LCanPointeeTy->isFunctionType() || RCanPointeeTy->isFunctionType()) 6725 && !LHSIsNull && !RHSIsNull) { 6726 diagnoseFunctionPointerToVoidComparison( 6727 *this, Loc, LHS, RHS, /*isError*/ isSFINAEContext()); 6728 6729 if (isSFINAEContext()) 6730 return QualType(); 6731 6732 RHS = ImpCastExprToType(RHS.take(), LHSType, CK_BitCast); 6733 return ResultTy; 6734 } 6735 } 6736 6737 if (convertPointersToCompositeType(*this, Loc, LHS, RHS)) 6738 return QualType(); 6739 else 6740 return ResultTy; 6741 } 6742 // C99 6.5.9p2 and C99 6.5.8p2 6743 if (Context.typesAreCompatible(LCanPointeeTy.getUnqualifiedType(), 6744 RCanPointeeTy.getUnqualifiedType())) { 6745 // Valid unless a relational comparison of function pointers 6746 if (IsRelational && LCanPointeeTy->isFunctionType()) { 6747 Diag(Loc, diag::ext_typecheck_ordered_comparison_of_function_pointers) 6748 << LHSType << RHSType << LHS.get()->getSourceRange() 6749 << RHS.get()->getSourceRange(); 6750 } 6751 } else if (!IsRelational && 6752 (LCanPointeeTy->isVoidType() || RCanPointeeTy->isVoidType())) { 6753 // Valid unless comparison between non-null pointer and function pointer 6754 if ((LCanPointeeTy->isFunctionType() || RCanPointeeTy->isFunctionType()) 6755 && !LHSIsNull && !RHSIsNull) 6756 diagnoseFunctionPointerToVoidComparison(*this, Loc, LHS, RHS, 6757 /*isError*/false); 6758 } else { 6759 // Invalid 6760 diagnoseDistinctPointerComparison(*this, Loc, LHS, RHS, /*isError*/false); 6761 } 6762 if (LCanPointeeTy != RCanPointeeTy) { 6763 if (LHSIsNull && !RHSIsNull) 6764 LHS = ImpCastExprToType(LHS.take(), RHSType, CK_BitCast); 6765 else 6766 RHS = ImpCastExprToType(RHS.take(), LHSType, CK_BitCast); 6767 } 6768 return ResultTy; 6769 } 6770 6771 if (getLangOpts().CPlusPlus) { 6772 // Comparison of nullptr_t with itself. 6773 if (LHSType->isNullPtrType() && RHSType->isNullPtrType()) 6774 return ResultTy; 6775 6776 // Comparison of pointers with null pointer constants and equality 6777 // comparisons of member pointers to null pointer constants. 6778 if (RHSIsNull && 6779 ((LHSType->isAnyPointerType() || LHSType->isNullPtrType()) || 6780 (!IsRelational && 6781 (LHSType->isMemberPointerType() || LHSType->isBlockPointerType())))) { 6782 RHS = ImpCastExprToType(RHS.take(), LHSType, 6783 LHSType->isMemberPointerType() 6784 ? CK_NullToMemberPointer 6785 : CK_NullToPointer); 6786 return ResultTy; 6787 } 6788 if (LHSIsNull && 6789 ((RHSType->isAnyPointerType() || RHSType->isNullPtrType()) || 6790 (!IsRelational && 6791 (RHSType->isMemberPointerType() || RHSType->isBlockPointerType())))) { 6792 LHS = ImpCastExprToType(LHS.take(), RHSType, 6793 RHSType->isMemberPointerType() 6794 ? CK_NullToMemberPointer 6795 : CK_NullToPointer); 6796 return ResultTy; 6797 } 6798 6799 // Comparison of member pointers. 6800 if (!IsRelational && 6801 LHSType->isMemberPointerType() && RHSType->isMemberPointerType()) { 6802 if (convertPointersToCompositeType(*this, Loc, LHS, RHS)) 6803 return QualType(); 6804 else 6805 return ResultTy; 6806 } 6807 6808 // Handle scoped enumeration types specifically, since they don't promote 6809 // to integers. 6810 if (LHS.get()->getType()->isEnumeralType() && 6811 Context.hasSameUnqualifiedType(LHS.get()->getType(), 6812 RHS.get()->getType())) 6813 return ResultTy; 6814 } 6815 6816 // Handle block pointer types. 6817 if (!IsRelational && LHSType->isBlockPointerType() && 6818 RHSType->isBlockPointerType()) { 6819 QualType lpointee = LHSType->castAs<BlockPointerType>()->getPointeeType(); 6820 QualType rpointee = RHSType->castAs<BlockPointerType>()->getPointeeType(); 6821 6822 if (!LHSIsNull && !RHSIsNull && 6823 !Context.typesAreCompatible(lpointee, rpointee)) { 6824 Diag(Loc, diag::err_typecheck_comparison_of_distinct_blocks) 6825 << LHSType << RHSType << LHS.get()->getSourceRange() 6826 << RHS.get()->getSourceRange(); 6827 } 6828 RHS = ImpCastExprToType(RHS.take(), LHSType, CK_BitCast); 6829 return ResultTy; 6830 } 6831 6832 // Allow block pointers to be compared with null pointer constants. 6833 if (!IsRelational 6834 && ((LHSType->isBlockPointerType() && RHSType->isPointerType()) 6835 || (LHSType->isPointerType() && RHSType->isBlockPointerType()))) { 6836 if (!LHSIsNull && !RHSIsNull) { 6837 if (!((RHSType->isPointerType() && RHSType->castAs<PointerType>() 6838 ->getPointeeType()->isVoidType()) 6839 || (LHSType->isPointerType() && LHSType->castAs<PointerType>() 6840 ->getPointeeType()->isVoidType()))) 6841 Diag(Loc, diag::err_typecheck_comparison_of_distinct_blocks) 6842 << LHSType << RHSType << LHS.get()->getSourceRange() 6843 << RHS.get()->getSourceRange(); 6844 } 6845 if (LHSIsNull && !RHSIsNull) 6846 LHS = ImpCastExprToType(LHS.take(), RHSType, 6847 RHSType->isPointerType() ? CK_BitCast 6848 : CK_AnyPointerToBlockPointerCast); 6849 else 6850 RHS = ImpCastExprToType(RHS.take(), LHSType, 6851 LHSType->isPointerType() ? CK_BitCast 6852 : CK_AnyPointerToBlockPointerCast); 6853 return ResultTy; 6854 } 6855 6856 if (LHSType->isObjCObjectPointerType() || 6857 RHSType->isObjCObjectPointerType()) { 6858 const PointerType *LPT = LHSType->getAs<PointerType>(); 6859 const PointerType *RPT = RHSType->getAs<PointerType>(); 6860 if (LPT || RPT) { 6861 bool LPtrToVoid = LPT ? LPT->getPointeeType()->isVoidType() : false; 6862 bool RPtrToVoid = RPT ? RPT->getPointeeType()->isVoidType() : false; 6863 6864 if (!LPtrToVoid && !RPtrToVoid && 6865 !Context.typesAreCompatible(LHSType, RHSType)) { 6866 diagnoseDistinctPointerComparison(*this, Loc, LHS, RHS, 6867 /*isError*/false); 6868 } 6869 if (LHSIsNull && !RHSIsNull) 6870 LHS = ImpCastExprToType(LHS.take(), RHSType, 6871 RPT ? CK_BitCast :CK_CPointerToObjCPointerCast); 6872 else 6873 RHS = ImpCastExprToType(RHS.take(), LHSType, 6874 LPT ? CK_BitCast :CK_CPointerToObjCPointerCast); 6875 return ResultTy; 6876 } 6877 if (LHSType->isObjCObjectPointerType() && 6878 RHSType->isObjCObjectPointerType()) { 6879 if (!Context.areComparableObjCPointerTypes(LHSType, RHSType)) 6880 diagnoseDistinctPointerComparison(*this, Loc, LHS, RHS, 6881 /*isError*/false); 6882 if (LHSIsNull && !RHSIsNull) 6883 LHS = ImpCastExprToType(LHS.take(), RHSType, CK_BitCast); 6884 else 6885 RHS = ImpCastExprToType(RHS.take(), LHSType, CK_BitCast); 6886 return ResultTy; 6887 } 6888 } 6889 if ((LHSType->isAnyPointerType() && RHSType->isIntegerType()) || 6890 (LHSType->isIntegerType() && RHSType->isAnyPointerType())) { 6891 unsigned DiagID = 0; 6892 bool isError = false; 6893 if ((LHSIsNull && LHSType->isIntegerType()) || 6894 (RHSIsNull && RHSType->isIntegerType())) { 6895 if (IsRelational && !getLangOpts().CPlusPlus) 6896 DiagID = diag::ext_typecheck_ordered_comparison_of_pointer_and_zero; 6897 } else if (IsRelational && !getLangOpts().CPlusPlus) 6898 DiagID = diag::ext_typecheck_ordered_comparison_of_pointer_integer; 6899 else if (getLangOpts().CPlusPlus) { 6900 DiagID = diag::err_typecheck_comparison_of_pointer_integer; 6901 isError = true; 6902 } else 6903 DiagID = diag::ext_typecheck_comparison_of_pointer_integer; 6904 6905 if (DiagID) { 6906 Diag(Loc, DiagID) 6907 << LHSType << RHSType << LHS.get()->getSourceRange() 6908 << RHS.get()->getSourceRange(); 6909 if (isError) 6910 return QualType(); 6911 } 6912 6913 if (LHSType->isIntegerType()) 6914 LHS = ImpCastExprToType(LHS.take(), RHSType, 6915 LHSIsNull ? CK_NullToPointer : CK_IntegralToPointer); 6916 else 6917 RHS = ImpCastExprToType(RHS.take(), LHSType, 6918 RHSIsNull ? CK_NullToPointer : CK_IntegralToPointer); 6919 return ResultTy; 6920 } 6921 6922 // Handle block pointers. 6923 if (!IsRelational && RHSIsNull 6924 && LHSType->isBlockPointerType() && RHSType->isIntegerType()) { 6925 RHS = ImpCastExprToType(RHS.take(), LHSType, CK_NullToPointer); 6926 return ResultTy; 6927 } 6928 if (!IsRelational && LHSIsNull 6929 && LHSType->isIntegerType() && RHSType->isBlockPointerType()) { 6930 LHS = ImpCastExprToType(LHS.take(), RHSType, CK_NullToPointer); 6931 return ResultTy; 6932 } 6933 6934 return InvalidOperands(Loc, LHS, RHS); 6935} 6936 6937 6938// Return a signed type that is of identical size and number of elements. 6939// For floating point vectors, return an integer type of identical size 6940// and number of elements. 6941QualType Sema::GetSignedVectorType(QualType V) { 6942 const VectorType *VTy = V->getAs<VectorType>(); 6943 unsigned TypeSize = Context.getTypeSize(VTy->getElementType()); 6944 if (TypeSize == Context.getTypeSize(Context.CharTy)) 6945 return Context.getExtVectorType(Context.CharTy, VTy->getNumElements()); 6946 else if (TypeSize == Context.getTypeSize(Context.ShortTy)) 6947 return Context.getExtVectorType(Context.ShortTy, VTy->getNumElements()); 6948 else if (TypeSize == Context.getTypeSize(Context.IntTy)) 6949 return Context.getExtVectorType(Context.IntTy, VTy->getNumElements()); 6950 else if (TypeSize == Context.getTypeSize(Context.LongTy)) 6951 return Context.getExtVectorType(Context.LongTy, VTy->getNumElements()); 6952 assert(TypeSize == Context.getTypeSize(Context.LongLongTy) && 6953 "Unhandled vector element size in vector compare"); 6954 return Context.getExtVectorType(Context.LongLongTy, VTy->getNumElements()); 6955} 6956 6957/// CheckVectorCompareOperands - vector comparisons are a clang extension that 6958/// operates on extended vector types. Instead of producing an IntTy result, 6959/// like a scalar comparison, a vector comparison produces a vector of integer 6960/// types. 6961QualType Sema::CheckVectorCompareOperands(ExprResult &LHS, ExprResult &RHS, 6962 SourceLocation Loc, 6963 bool IsRelational) { 6964 // Check to make sure we're operating on vectors of the same type and width, 6965 // Allowing one side to be a scalar of element type. 6966 QualType vType = CheckVectorOperands(LHS, RHS, Loc, /*isCompAssign*/false); 6967 if (vType.isNull()) 6968 return vType; 6969 6970 QualType LHSType = LHS.get()->getType(); 6971 6972 // If AltiVec, the comparison results in a numeric type, i.e. 6973 // bool for C++, int for C 6974 if (vType->getAs<VectorType>()->getVectorKind() == VectorType::AltiVecVector) 6975 return Context.getLogicalOperationType(); 6976 6977 // For non-floating point types, check for self-comparisons of the form 6978 // x == x, x != x, x < x, etc. These always evaluate to a constant, and 6979 // often indicate logic errors in the program. 6980 if (!LHSType->hasFloatingRepresentation()) { 6981 if (DeclRefExpr* DRL 6982 = dyn_cast<DeclRefExpr>(LHS.get()->IgnoreParenImpCasts())) 6983 if (DeclRefExpr* DRR 6984 = dyn_cast<DeclRefExpr>(RHS.get()->IgnoreParenImpCasts())) 6985 if (DRL->getDecl() == DRR->getDecl()) 6986 DiagRuntimeBehavior(Loc, 0, 6987 PDiag(diag::warn_comparison_always) 6988 << 0 // self- 6989 << 2 // "a constant" 6990 ); 6991 } 6992 6993 // Check for comparisons of floating point operands using != and ==. 6994 if (!IsRelational && LHSType->hasFloatingRepresentation()) { 6995 assert (RHS.get()->getType()->hasFloatingRepresentation()); 6996 CheckFloatComparison(Loc, LHS.get(), RHS.get()); 6997 } 6998 6999 // Return a signed type for the vector. 7000 return GetSignedVectorType(LHSType); 7001} 7002 7003QualType Sema::CheckVectorLogicalOperands(ExprResult &LHS, ExprResult &RHS, 7004 SourceLocation Loc) { 7005 // Ensure that either both operands are of the same vector type, or 7006 // one operand is of a vector type and the other is of its element type. 7007 QualType vType = CheckVectorOperands(LHS, RHS, Loc, false); 7008 if (vType.isNull() || vType->isFloatingType()) 7009 return InvalidOperands(Loc, LHS, RHS); 7010 7011 return GetSignedVectorType(LHS.get()->getType()); 7012} 7013 7014inline QualType Sema::CheckBitwiseOperands( 7015 ExprResult &LHS, ExprResult &RHS, SourceLocation Loc, bool IsCompAssign) { 7016 checkArithmeticNull(*this, LHS, RHS, Loc, /*isCompare=*/false); 7017 7018 if (LHS.get()->getType()->isVectorType() || 7019 RHS.get()->getType()->isVectorType()) { 7020 if (LHS.get()->getType()->hasIntegerRepresentation() && 7021 RHS.get()->getType()->hasIntegerRepresentation()) 7022 return CheckVectorOperands(LHS, RHS, Loc, IsCompAssign); 7023 7024 return InvalidOperands(Loc, LHS, RHS); 7025 } 7026 7027 ExprResult LHSResult = Owned(LHS), RHSResult = Owned(RHS); 7028 QualType compType = UsualArithmeticConversions(LHSResult, RHSResult, 7029 IsCompAssign); 7030 if (LHSResult.isInvalid() || RHSResult.isInvalid()) 7031 return QualType(); 7032 LHS = LHSResult.take(); 7033 RHS = RHSResult.take(); 7034 7035 if (LHS.get()->getType()->isIntegralOrUnscopedEnumerationType() && 7036 RHS.get()->getType()->isIntegralOrUnscopedEnumerationType()) 7037 return compType; 7038 return InvalidOperands(Loc, LHS, RHS); 7039} 7040 7041inline QualType Sema::CheckLogicalOperands( // C99 6.5.[13,14] 7042 ExprResult &LHS, ExprResult &RHS, SourceLocation Loc, unsigned Opc) { 7043 7044 // Check vector operands differently. 7045 if (LHS.get()->getType()->isVectorType() || RHS.get()->getType()->isVectorType()) 7046 return CheckVectorLogicalOperands(LHS, RHS, Loc); 7047 7048 // Diagnose cases where the user write a logical and/or but probably meant a 7049 // bitwise one. We do this when the LHS is a non-bool integer and the RHS 7050 // is a constant. 7051 if (LHS.get()->getType()->isIntegerType() && 7052 !LHS.get()->getType()->isBooleanType() && 7053 RHS.get()->getType()->isIntegerType() && !RHS.get()->isValueDependent() && 7054 // Don't warn in macros or template instantiations. 7055 !Loc.isMacroID() && ActiveTemplateInstantiations.empty()) { 7056 // If the RHS can be constant folded, and if it constant folds to something 7057 // that isn't 0 or 1 (which indicate a potential logical operation that 7058 // happened to fold to true/false) then warn. 7059 // Parens on the RHS are ignored. 7060 llvm::APSInt Result; 7061 if (RHS.get()->EvaluateAsInt(Result, Context)) 7062 if ((getLangOpts().Bool && !RHS.get()->getType()->isBooleanType()) || 7063 (Result != 0 && Result != 1)) { 7064 Diag(Loc, diag::warn_logical_instead_of_bitwise) 7065 << RHS.get()->getSourceRange() 7066 << (Opc == BO_LAnd ? "&&" : "||"); 7067 // Suggest replacing the logical operator with the bitwise version 7068 Diag(Loc, diag::note_logical_instead_of_bitwise_change_operator) 7069 << (Opc == BO_LAnd ? "&" : "|") 7070 << FixItHint::CreateReplacement(SourceRange( 7071 Loc, Lexer::getLocForEndOfToken(Loc, 0, getSourceManager(), 7072 getLangOpts())), 7073 Opc == BO_LAnd ? "&" : "|"); 7074 if (Opc == BO_LAnd) 7075 // Suggest replacing "Foo() && kNonZero" with "Foo()" 7076 Diag(Loc, diag::note_logical_instead_of_bitwise_remove_constant) 7077 << FixItHint::CreateRemoval( 7078 SourceRange( 7079 Lexer::getLocForEndOfToken(LHS.get()->getLocEnd(), 7080 0, getSourceManager(), 7081 getLangOpts()), 7082 RHS.get()->getLocEnd())); 7083 } 7084 } 7085 7086 if (!Context.getLangOpts().CPlusPlus) { 7087 LHS = UsualUnaryConversions(LHS.take()); 7088 if (LHS.isInvalid()) 7089 return QualType(); 7090 7091 RHS = UsualUnaryConversions(RHS.take()); 7092 if (RHS.isInvalid()) 7093 return QualType(); 7094 7095 if (!LHS.get()->getType()->isScalarType() || 7096 !RHS.get()->getType()->isScalarType()) 7097 return InvalidOperands(Loc, LHS, RHS); 7098 7099 return Context.IntTy; 7100 } 7101 7102 // The following is safe because we only use this method for 7103 // non-overloadable operands. 7104 7105 // C++ [expr.log.and]p1 7106 // C++ [expr.log.or]p1 7107 // The operands are both contextually converted to type bool. 7108 ExprResult LHSRes = PerformContextuallyConvertToBool(LHS.get()); 7109 if (LHSRes.isInvalid()) 7110 return InvalidOperands(Loc, LHS, RHS); 7111 LHS = move(LHSRes); 7112 7113 ExprResult RHSRes = PerformContextuallyConvertToBool(RHS.get()); 7114 if (RHSRes.isInvalid()) 7115 return InvalidOperands(Loc, LHS, RHS); 7116 RHS = move(RHSRes); 7117 7118 // C++ [expr.log.and]p2 7119 // C++ [expr.log.or]p2 7120 // The result is a bool. 7121 return Context.BoolTy; 7122} 7123 7124/// IsReadonlyProperty - Verify that otherwise a valid l-value expression 7125/// is a read-only property; return true if so. A readonly property expression 7126/// depends on various declarations and thus must be treated specially. 7127/// 7128static bool IsReadonlyProperty(Expr *E, Sema &S) { 7129 const ObjCPropertyRefExpr *PropExpr = dyn_cast<ObjCPropertyRefExpr>(E); 7130 if (!PropExpr) return false; 7131 if (PropExpr->isImplicitProperty()) return false; 7132 7133 ObjCPropertyDecl *PDecl = PropExpr->getExplicitProperty(); 7134 QualType BaseType = PropExpr->isSuperReceiver() ? 7135 PropExpr->getSuperReceiverType() : 7136 PropExpr->getBase()->getType(); 7137 7138 if (const ObjCObjectPointerType *OPT = 7139 BaseType->getAsObjCInterfacePointerType()) 7140 if (ObjCInterfaceDecl *IFace = OPT->getInterfaceDecl()) 7141 if (S.isPropertyReadonly(PDecl, IFace)) 7142 return true; 7143 return false; 7144} 7145 7146static bool IsConstProperty(Expr *E, Sema &S) { 7147 const ObjCPropertyRefExpr *PropExpr = dyn_cast<ObjCPropertyRefExpr>(E); 7148 if (!PropExpr) return false; 7149 if (PropExpr->isImplicitProperty()) return false; 7150 7151 ObjCPropertyDecl *PDecl = PropExpr->getExplicitProperty(); 7152 QualType T = PDecl->getType().getNonReferenceType(); 7153 return T.isConstQualified(); 7154} 7155 7156static bool IsReadonlyMessage(Expr *E, Sema &S) { 7157 const MemberExpr *ME = dyn_cast<MemberExpr>(E); 7158 if (!ME) return false; 7159 if (!isa<FieldDecl>(ME->getMemberDecl())) return false; 7160 ObjCMessageExpr *Base = 7161 dyn_cast<ObjCMessageExpr>(ME->getBase()->IgnoreParenImpCasts()); 7162 if (!Base) return false; 7163 return Base->getMethodDecl() != 0; 7164} 7165 7166/// Is the given expression (which must be 'const') a reference to a 7167/// variable which was originally non-const, but which has become 7168/// 'const' due to being captured within a block? 7169enum NonConstCaptureKind { NCCK_None, NCCK_Block, NCCK_Lambda }; 7170static NonConstCaptureKind isReferenceToNonConstCapture(Sema &S, Expr *E) { 7171 assert(E->isLValue() && E->getType().isConstQualified()); 7172 E = E->IgnoreParens(); 7173 7174 // Must be a reference to a declaration from an enclosing scope. 7175 DeclRefExpr *DRE = dyn_cast<DeclRefExpr>(E); 7176 if (!DRE) return NCCK_None; 7177 if (!DRE->refersToEnclosingLocal()) return NCCK_None; 7178 7179 // The declaration must be a variable which is not declared 'const'. 7180 VarDecl *var = dyn_cast<VarDecl>(DRE->getDecl()); 7181 if (!var) return NCCK_None; 7182 if (var->getType().isConstQualified()) return NCCK_None; 7183 assert(var->hasLocalStorage() && "capture added 'const' to non-local?"); 7184 7185 // Decide whether the first capture was for a block or a lambda. 7186 DeclContext *DC = S.CurContext; 7187 while (DC->getParent() != var->getDeclContext()) 7188 DC = DC->getParent(); 7189 return (isa<BlockDecl>(DC) ? NCCK_Block : NCCK_Lambda); 7190} 7191 7192/// CheckForModifiableLvalue - Verify that E is a modifiable lvalue. If not, 7193/// emit an error and return true. If so, return false. 7194static bool CheckForModifiableLvalue(Expr *E, SourceLocation Loc, Sema &S) { 7195 SourceLocation OrigLoc = Loc; 7196 Expr::isModifiableLvalueResult IsLV = E->isModifiableLvalue(S.Context, 7197 &Loc); 7198 if (IsLV == Expr::MLV_Valid && IsReadonlyProperty(E, S)) 7199 IsLV = Expr::MLV_ReadonlyProperty; 7200 else if (Expr::MLV_ConstQualified && IsConstProperty(E, S)) 7201 IsLV = Expr::MLV_Valid; 7202 else if (IsLV == Expr::MLV_ClassTemporary && IsReadonlyMessage(E, S)) 7203 IsLV = Expr::MLV_InvalidMessageExpression; 7204 if (IsLV == Expr::MLV_Valid) 7205 return false; 7206 7207 unsigned Diag = 0; 7208 bool NeedType = false; 7209 switch (IsLV) { // C99 6.5.16p2 7210 case Expr::MLV_ConstQualified: 7211 Diag = diag::err_typecheck_assign_const; 7212 7213 // Use a specialized diagnostic when we're assigning to an object 7214 // from an enclosing function or block. 7215 if (NonConstCaptureKind NCCK = isReferenceToNonConstCapture(S, E)) { 7216 if (NCCK == NCCK_Block) 7217 Diag = diag::err_block_decl_ref_not_modifiable_lvalue; 7218 else 7219 Diag = diag::err_lambda_decl_ref_not_modifiable_lvalue; 7220 break; 7221 } 7222 7223 // In ARC, use some specialized diagnostics for occasions where we 7224 // infer 'const'. These are always pseudo-strong variables. 7225 if (S.getLangOpts().ObjCAutoRefCount) { 7226 DeclRefExpr *declRef = dyn_cast<DeclRefExpr>(E->IgnoreParenCasts()); 7227 if (declRef && isa<VarDecl>(declRef->getDecl())) { 7228 VarDecl *var = cast<VarDecl>(declRef->getDecl()); 7229 7230 // Use the normal diagnostic if it's pseudo-__strong but the 7231 // user actually wrote 'const'. 7232 if (var->isARCPseudoStrong() && 7233 (!var->getTypeSourceInfo() || 7234 !var->getTypeSourceInfo()->getType().isConstQualified())) { 7235 // There are two pseudo-strong cases: 7236 // - self 7237 ObjCMethodDecl *method = S.getCurMethodDecl(); 7238 if (method && var == method->getSelfDecl()) 7239 Diag = method->isClassMethod() 7240 ? diag::err_typecheck_arc_assign_self_class_method 7241 : diag::err_typecheck_arc_assign_self; 7242 7243 // - fast enumeration variables 7244 else 7245 Diag = diag::err_typecheck_arr_assign_enumeration; 7246 7247 SourceRange Assign; 7248 if (Loc != OrigLoc) 7249 Assign = SourceRange(OrigLoc, OrigLoc); 7250 S.Diag(Loc, Diag) << E->getSourceRange() << Assign; 7251 // We need to preserve the AST regardless, so migration tool 7252 // can do its job. 7253 return false; 7254 } 7255 } 7256 } 7257 7258 break; 7259 case Expr::MLV_ArrayType: 7260 Diag = diag::err_typecheck_array_not_modifiable_lvalue; 7261 NeedType = true; 7262 break; 7263 case Expr::MLV_NotObjectType: 7264 Diag = diag::err_typecheck_non_object_not_modifiable_lvalue; 7265 NeedType = true; 7266 break; 7267 case Expr::MLV_LValueCast: 7268 Diag = diag::err_typecheck_lvalue_casts_not_supported; 7269 break; 7270 case Expr::MLV_Valid: 7271 llvm_unreachable("did not take early return for MLV_Valid"); 7272 case Expr::MLV_InvalidExpression: 7273 case Expr::MLV_MemberFunction: 7274 case Expr::MLV_ClassTemporary: 7275 Diag = diag::err_typecheck_expression_not_modifiable_lvalue; 7276 break; 7277 case Expr::MLV_IncompleteType: 7278 case Expr::MLV_IncompleteVoidType: 7279 return S.RequireCompleteType(Loc, E->getType(), 7280 S.PDiag(diag::err_typecheck_incomplete_type_not_modifiable_lvalue) 7281 << E->getSourceRange()); 7282 case Expr::MLV_DuplicateVectorComponents: 7283 Diag = diag::err_typecheck_duplicate_vector_components_not_mlvalue; 7284 break; 7285 case Expr::MLV_ReadonlyProperty: 7286 case Expr::MLV_NoSetterProperty: 7287 llvm_unreachable("readonly properties should be processed differently"); 7288 case Expr::MLV_InvalidMessageExpression: 7289 Diag = diag::error_readonly_message_assignment; 7290 break; 7291 case Expr::MLV_SubObjCPropertySetting: 7292 Diag = diag::error_no_subobject_property_setting; 7293 break; 7294 } 7295 7296 SourceRange Assign; 7297 if (Loc != OrigLoc) 7298 Assign = SourceRange(OrigLoc, OrigLoc); 7299 if (NeedType) 7300 S.Diag(Loc, Diag) << E->getType() << E->getSourceRange() << Assign; 7301 else 7302 S.Diag(Loc, Diag) << E->getSourceRange() << Assign; 7303 return true; 7304} 7305 7306 7307 7308// C99 6.5.16.1 7309QualType Sema::CheckAssignmentOperands(Expr *LHSExpr, ExprResult &RHS, 7310 SourceLocation Loc, 7311 QualType CompoundType) { 7312 assert(!LHSExpr->hasPlaceholderType(BuiltinType::PseudoObject)); 7313 7314 // Verify that LHS is a modifiable lvalue, and emit error if not. 7315 if (CheckForModifiableLvalue(LHSExpr, Loc, *this)) 7316 return QualType(); 7317 7318 QualType LHSType = LHSExpr->getType(); 7319 QualType RHSType = CompoundType.isNull() ? RHS.get()->getType() : 7320 CompoundType; 7321 AssignConvertType ConvTy; 7322 if (CompoundType.isNull()) { 7323 QualType LHSTy(LHSType); 7324 ConvTy = CheckSingleAssignmentConstraints(LHSTy, RHS); 7325 if (RHS.isInvalid()) 7326 return QualType(); 7327 // Special case of NSObject attributes on c-style pointer types. 7328 if (ConvTy == IncompatiblePointer && 7329 ((Context.isObjCNSObjectType(LHSType) && 7330 RHSType->isObjCObjectPointerType()) || 7331 (Context.isObjCNSObjectType(RHSType) && 7332 LHSType->isObjCObjectPointerType()))) 7333 ConvTy = Compatible; 7334 7335 if (ConvTy == Compatible && 7336 LHSType->isObjCObjectType()) 7337 Diag(Loc, diag::err_objc_object_assignment) 7338 << LHSType; 7339 7340 // If the RHS is a unary plus or minus, check to see if they = and + are 7341 // right next to each other. If so, the user may have typo'd "x =+ 4" 7342 // instead of "x += 4". 7343 Expr *RHSCheck = RHS.get(); 7344 if (ImplicitCastExpr *ICE = dyn_cast<ImplicitCastExpr>(RHSCheck)) 7345 RHSCheck = ICE->getSubExpr(); 7346 if (UnaryOperator *UO = dyn_cast<UnaryOperator>(RHSCheck)) { 7347 if ((UO->getOpcode() == UO_Plus || 7348 UO->getOpcode() == UO_Minus) && 7349 Loc.isFileID() && UO->getOperatorLoc().isFileID() && 7350 // Only if the two operators are exactly adjacent. 7351 Loc.getLocWithOffset(1) == UO->getOperatorLoc() && 7352 // And there is a space or other character before the subexpr of the 7353 // unary +/-. We don't want to warn on "x=-1". 7354 Loc.getLocWithOffset(2) != UO->getSubExpr()->getLocStart() && 7355 UO->getSubExpr()->getLocStart().isFileID()) { 7356 Diag(Loc, diag::warn_not_compound_assign) 7357 << (UO->getOpcode() == UO_Plus ? "+" : "-") 7358 << SourceRange(UO->getOperatorLoc(), UO->getOperatorLoc()); 7359 } 7360 } 7361 7362 if (ConvTy == Compatible) { 7363 if (LHSType.getObjCLifetime() == Qualifiers::OCL_Strong) 7364 checkRetainCycles(LHSExpr, RHS.get()); 7365 else if (getLangOpts().ObjCAutoRefCount) 7366 checkUnsafeExprAssigns(Loc, LHSExpr, RHS.get()); 7367 } 7368 } else { 7369 // Compound assignment "x += y" 7370 ConvTy = CheckAssignmentConstraints(Loc, LHSType, RHSType); 7371 } 7372 7373 if (DiagnoseAssignmentResult(ConvTy, Loc, LHSType, RHSType, 7374 RHS.get(), AA_Assigning)) 7375 return QualType(); 7376 7377 CheckForNullPointerDereference(*this, LHSExpr); 7378 7379 // C99 6.5.16p3: The type of an assignment expression is the type of the 7380 // left operand unless the left operand has qualified type, in which case 7381 // it is the unqualified version of the type of the left operand. 7382 // C99 6.5.16.1p2: In simple assignment, the value of the right operand 7383 // is converted to the type of the assignment expression (above). 7384 // C++ 5.17p1: the type of the assignment expression is that of its left 7385 // operand. 7386 return (getLangOpts().CPlusPlus 7387 ? LHSType : LHSType.getUnqualifiedType()); 7388} 7389 7390// C99 6.5.17 7391static QualType CheckCommaOperands(Sema &S, ExprResult &LHS, ExprResult &RHS, 7392 SourceLocation Loc) { 7393 S.DiagnoseUnusedExprResult(LHS.get()); 7394 7395 LHS = S.CheckPlaceholderExpr(LHS.take()); 7396 RHS = S.CheckPlaceholderExpr(RHS.take()); 7397 if (LHS.isInvalid() || RHS.isInvalid()) 7398 return QualType(); 7399 7400 // C's comma performs lvalue conversion (C99 6.3.2.1) on both its 7401 // operands, but not unary promotions. 7402 // C++'s comma does not do any conversions at all (C++ [expr.comma]p1). 7403 7404 // So we treat the LHS as a ignored value, and in C++ we allow the 7405 // containing site to determine what should be done with the RHS. 7406 LHS = S.IgnoredValueConversions(LHS.take()); 7407 if (LHS.isInvalid()) 7408 return QualType(); 7409 7410 if (!S.getLangOpts().CPlusPlus) { 7411 RHS = S.DefaultFunctionArrayLvalueConversion(RHS.take()); 7412 if (RHS.isInvalid()) 7413 return QualType(); 7414 if (!RHS.get()->getType()->isVoidType()) 7415 S.RequireCompleteType(Loc, RHS.get()->getType(), 7416 diag::err_incomplete_type); 7417 } 7418 7419 return RHS.get()->getType(); 7420} 7421 7422/// CheckIncrementDecrementOperand - unlike most "Check" methods, this routine 7423/// doesn't need to call UsualUnaryConversions or UsualArithmeticConversions. 7424static QualType CheckIncrementDecrementOperand(Sema &S, Expr *Op, 7425 ExprValueKind &VK, 7426 SourceLocation OpLoc, 7427 bool IsInc, bool IsPrefix) { 7428 if (Op->isTypeDependent()) 7429 return S.Context.DependentTy; 7430 7431 QualType ResType = Op->getType(); 7432 // Atomic types can be used for increment / decrement where the non-atomic 7433 // versions can, so ignore the _Atomic() specifier for the purpose of 7434 // checking. 7435 if (const AtomicType *ResAtomicType = ResType->getAs<AtomicType>()) 7436 ResType = ResAtomicType->getValueType(); 7437 7438 assert(!ResType.isNull() && "no type for increment/decrement expression"); 7439 7440 if (S.getLangOpts().CPlusPlus && ResType->isBooleanType()) { 7441 // Decrement of bool is not allowed. 7442 if (!IsInc) { 7443 S.Diag(OpLoc, diag::err_decrement_bool) << Op->getSourceRange(); 7444 return QualType(); 7445 } 7446 // Increment of bool sets it to true, but is deprecated. 7447 S.Diag(OpLoc, diag::warn_increment_bool) << Op->getSourceRange(); 7448 } else if (ResType->isRealType()) { 7449 // OK! 7450 } else if (ResType->isAnyPointerType()) { 7451 // C99 6.5.2.4p2, 6.5.6p2 7452 if (!checkArithmeticOpPointerOperand(S, OpLoc, Op)) 7453 return QualType(); 7454 7455 // Diagnose bad cases where we step over interface counts. 7456 else if (!checkArithmethicPointerOnNonFragileABI(S, OpLoc, Op)) 7457 return QualType(); 7458 } else if (ResType->isAnyComplexType()) { 7459 // C99 does not support ++/-- on complex types, we allow as an extension. 7460 S.Diag(OpLoc, diag::ext_integer_increment_complex) 7461 << ResType << Op->getSourceRange(); 7462 } else if (ResType->isPlaceholderType()) { 7463 ExprResult PR = S.CheckPlaceholderExpr(Op); 7464 if (PR.isInvalid()) return QualType(); 7465 return CheckIncrementDecrementOperand(S, PR.take(), VK, OpLoc, 7466 IsInc, IsPrefix); 7467 } else if (S.getLangOpts().AltiVec && ResType->isVectorType()) { 7468 // OK! ( C/C++ Language Extensions for CBEA(Version 2.6) 10.3 ) 7469 } else { 7470 S.Diag(OpLoc, diag::err_typecheck_illegal_increment_decrement) 7471 << ResType << int(IsInc) << Op->getSourceRange(); 7472 return QualType(); 7473 } 7474 // At this point, we know we have a real, complex or pointer type. 7475 // Now make sure the operand is a modifiable lvalue. 7476 if (CheckForModifiableLvalue(Op, OpLoc, S)) 7477 return QualType(); 7478 // In C++, a prefix increment is the same type as the operand. Otherwise 7479 // (in C or with postfix), the increment is the unqualified type of the 7480 // operand. 7481 if (IsPrefix && S.getLangOpts().CPlusPlus) { 7482 VK = VK_LValue; 7483 return ResType; 7484 } else { 7485 VK = VK_RValue; 7486 return ResType.getUnqualifiedType(); 7487 } 7488} 7489 7490 7491/// getPrimaryDecl - Helper function for CheckAddressOfOperand(). 7492/// This routine allows us to typecheck complex/recursive expressions 7493/// where the declaration is needed for type checking. We only need to 7494/// handle cases when the expression references a function designator 7495/// or is an lvalue. Here are some examples: 7496/// - &(x) => x 7497/// - &*****f => f for f a function designator. 7498/// - &s.xx => s 7499/// - &s.zz[1].yy -> s, if zz is an array 7500/// - *(x + 1) -> x, if x is an array 7501/// - &"123"[2] -> 0 7502/// - & __real__ x -> x 7503static ValueDecl *getPrimaryDecl(Expr *E) { 7504 switch (E->getStmtClass()) { 7505 case Stmt::DeclRefExprClass: 7506 return cast<DeclRefExpr>(E)->getDecl(); 7507 case Stmt::MemberExprClass: 7508 // If this is an arrow operator, the address is an offset from 7509 // the base's value, so the object the base refers to is 7510 // irrelevant. 7511 if (cast<MemberExpr>(E)->isArrow()) 7512 return 0; 7513 // Otherwise, the expression refers to a part of the base 7514 return getPrimaryDecl(cast<MemberExpr>(E)->getBase()); 7515 case Stmt::ArraySubscriptExprClass: { 7516 // FIXME: This code shouldn't be necessary! We should catch the implicit 7517 // promotion of register arrays earlier. 7518 Expr* Base = cast<ArraySubscriptExpr>(E)->getBase(); 7519 if (ImplicitCastExpr* ICE = dyn_cast<ImplicitCastExpr>(Base)) { 7520 if (ICE->getSubExpr()->getType()->isArrayType()) 7521 return getPrimaryDecl(ICE->getSubExpr()); 7522 } 7523 return 0; 7524 } 7525 case Stmt::UnaryOperatorClass: { 7526 UnaryOperator *UO = cast<UnaryOperator>(E); 7527 7528 switch(UO->getOpcode()) { 7529 case UO_Real: 7530 case UO_Imag: 7531 case UO_Extension: 7532 return getPrimaryDecl(UO->getSubExpr()); 7533 default: 7534 return 0; 7535 } 7536 } 7537 case Stmt::ParenExprClass: 7538 return getPrimaryDecl(cast<ParenExpr>(E)->getSubExpr()); 7539 case Stmt::ImplicitCastExprClass: 7540 // If the result of an implicit cast is an l-value, we care about 7541 // the sub-expression; otherwise, the result here doesn't matter. 7542 return getPrimaryDecl(cast<ImplicitCastExpr>(E)->getSubExpr()); 7543 default: 7544 return 0; 7545 } 7546} 7547 7548namespace { 7549 enum { 7550 AO_Bit_Field = 0, 7551 AO_Vector_Element = 1, 7552 AO_Property_Expansion = 2, 7553 AO_Register_Variable = 3, 7554 AO_No_Error = 4 7555 }; 7556} 7557/// \brief Diagnose invalid operand for address of operations. 7558/// 7559/// \param Type The type of operand which cannot have its address taken. 7560static void diagnoseAddressOfInvalidType(Sema &S, SourceLocation Loc, 7561 Expr *E, unsigned Type) { 7562 S.Diag(Loc, diag::err_typecheck_address_of) << Type << E->getSourceRange(); 7563} 7564 7565/// CheckAddressOfOperand - The operand of & must be either a function 7566/// designator or an lvalue designating an object. If it is an lvalue, the 7567/// object cannot be declared with storage class register or be a bit field. 7568/// Note: The usual conversions are *not* applied to the operand of the & 7569/// operator (C99 6.3.2.1p[2-4]), and its result is never an lvalue. 7570/// In C++, the operand might be an overloaded function name, in which case 7571/// we allow the '&' but retain the overloaded-function type. 7572static QualType CheckAddressOfOperand(Sema &S, ExprResult &OrigOp, 7573 SourceLocation OpLoc) { 7574 if (const BuiltinType *PTy = OrigOp.get()->getType()->getAsPlaceholderType()){ 7575 if (PTy->getKind() == BuiltinType::Overload) { 7576 if (!isa<OverloadExpr>(OrigOp.get()->IgnoreParens())) { 7577 S.Diag(OpLoc, diag::err_typecheck_invalid_lvalue_addrof) 7578 << OrigOp.get()->getSourceRange(); 7579 return QualType(); 7580 } 7581 7582 return S.Context.OverloadTy; 7583 } 7584 7585 if (PTy->getKind() == BuiltinType::UnknownAny) 7586 return S.Context.UnknownAnyTy; 7587 7588 if (PTy->getKind() == BuiltinType::BoundMember) { 7589 S.Diag(OpLoc, diag::err_invalid_form_pointer_member_function) 7590 << OrigOp.get()->getSourceRange(); 7591 return QualType(); 7592 } 7593 7594 OrigOp = S.CheckPlaceholderExpr(OrigOp.take()); 7595 if (OrigOp.isInvalid()) return QualType(); 7596 } 7597 7598 if (OrigOp.get()->isTypeDependent()) 7599 return S.Context.DependentTy; 7600 7601 assert(!OrigOp.get()->getType()->isPlaceholderType()); 7602 7603 // Make sure to ignore parentheses in subsequent checks 7604 Expr *op = OrigOp.get()->IgnoreParens(); 7605 7606 if (S.getLangOpts().C99) { 7607 // Implement C99-only parts of addressof rules. 7608 if (UnaryOperator* uOp = dyn_cast<UnaryOperator>(op)) { 7609 if (uOp->getOpcode() == UO_Deref) 7610 // Per C99 6.5.3.2, the address of a deref always returns a valid result 7611 // (assuming the deref expression is valid). 7612 return uOp->getSubExpr()->getType(); 7613 } 7614 // Technically, there should be a check for array subscript 7615 // expressions here, but the result of one is always an lvalue anyway. 7616 } 7617 ValueDecl *dcl = getPrimaryDecl(op); 7618 Expr::LValueClassification lval = op->ClassifyLValue(S.Context); 7619 unsigned AddressOfError = AO_No_Error; 7620 7621 if (lval == Expr::LV_ClassTemporary) { 7622 bool sfinae = S.isSFINAEContext(); 7623 S.Diag(OpLoc, sfinae ? diag::err_typecheck_addrof_class_temporary 7624 : diag::ext_typecheck_addrof_class_temporary) 7625 << op->getType() << op->getSourceRange(); 7626 if (sfinae) 7627 return QualType(); 7628 } else if (isa<ObjCSelectorExpr>(op)) { 7629 return S.Context.getPointerType(op->getType()); 7630 } else if (lval == Expr::LV_MemberFunction) { 7631 // If it's an instance method, make a member pointer. 7632 // The expression must have exactly the form &A::foo. 7633 7634 // If the underlying expression isn't a decl ref, give up. 7635 if (!isa<DeclRefExpr>(op)) { 7636 S.Diag(OpLoc, diag::err_invalid_form_pointer_member_function) 7637 << OrigOp.get()->getSourceRange(); 7638 return QualType(); 7639 } 7640 DeclRefExpr *DRE = cast<DeclRefExpr>(op); 7641 CXXMethodDecl *MD = cast<CXXMethodDecl>(DRE->getDecl()); 7642 7643 // The id-expression was parenthesized. 7644 if (OrigOp.get() != DRE) { 7645 S.Diag(OpLoc, diag::err_parens_pointer_member_function) 7646 << OrigOp.get()->getSourceRange(); 7647 7648 // The method was named without a qualifier. 7649 } else if (!DRE->getQualifier()) { 7650 S.Diag(OpLoc, diag::err_unqualified_pointer_member_function) 7651 << op->getSourceRange(); 7652 } 7653 7654 return S.Context.getMemberPointerType(op->getType(), 7655 S.Context.getTypeDeclType(MD->getParent()).getTypePtr()); 7656 } else if (lval != Expr::LV_Valid && lval != Expr::LV_IncompleteVoidType) { 7657 // C99 6.5.3.2p1 7658 // The operand must be either an l-value or a function designator 7659 if (!op->getType()->isFunctionType()) { 7660 // Use a special diagnostic for loads from property references. 7661 if (isa<PseudoObjectExpr>(op)) { 7662 AddressOfError = AO_Property_Expansion; 7663 } else { 7664 // FIXME: emit more specific diag... 7665 S.Diag(OpLoc, diag::err_typecheck_invalid_lvalue_addrof) 7666 << op->getSourceRange(); 7667 return QualType(); 7668 } 7669 } 7670 } else if (op->getObjectKind() == OK_BitField) { // C99 6.5.3.2p1 7671 // The operand cannot be a bit-field 7672 AddressOfError = AO_Bit_Field; 7673 } else if (op->getObjectKind() == OK_VectorComponent) { 7674 // The operand cannot be an element of a vector 7675 AddressOfError = AO_Vector_Element; 7676 } else if (dcl) { // C99 6.5.3.2p1 7677 // We have an lvalue with a decl. Make sure the decl is not declared 7678 // with the register storage-class specifier. 7679 if (const VarDecl *vd = dyn_cast<VarDecl>(dcl)) { 7680 // in C++ it is not error to take address of a register 7681 // variable (c++03 7.1.1P3) 7682 if (vd->getStorageClass() == SC_Register && 7683 !S.getLangOpts().CPlusPlus) { 7684 AddressOfError = AO_Register_Variable; 7685 } 7686 } else if (isa<FunctionTemplateDecl>(dcl)) { 7687 return S.Context.OverloadTy; 7688 } else if (isa<FieldDecl>(dcl) || isa<IndirectFieldDecl>(dcl)) { 7689 // Okay: we can take the address of a field. 7690 // Could be a pointer to member, though, if there is an explicit 7691 // scope qualifier for the class. 7692 if (isa<DeclRefExpr>(op) && cast<DeclRefExpr>(op)->getQualifier()) { 7693 DeclContext *Ctx = dcl->getDeclContext(); 7694 if (Ctx && Ctx->isRecord()) { 7695 if (dcl->getType()->isReferenceType()) { 7696 S.Diag(OpLoc, 7697 diag::err_cannot_form_pointer_to_member_of_reference_type) 7698 << dcl->getDeclName() << dcl->getType(); 7699 return QualType(); 7700 } 7701 7702 while (cast<RecordDecl>(Ctx)->isAnonymousStructOrUnion()) 7703 Ctx = Ctx->getParent(); 7704 return S.Context.getMemberPointerType(op->getType(), 7705 S.Context.getTypeDeclType(cast<RecordDecl>(Ctx)).getTypePtr()); 7706 } 7707 } 7708 } else if (!isa<FunctionDecl>(dcl) && !isa<NonTypeTemplateParmDecl>(dcl)) 7709 llvm_unreachable("Unknown/unexpected decl type"); 7710 } 7711 7712 if (AddressOfError != AO_No_Error) { 7713 diagnoseAddressOfInvalidType(S, OpLoc, op, AddressOfError); 7714 return QualType(); 7715 } 7716 7717 if (lval == Expr::LV_IncompleteVoidType) { 7718 // Taking the address of a void variable is technically illegal, but we 7719 // allow it in cases which are otherwise valid. 7720 // Example: "extern void x; void* y = &x;". 7721 S.Diag(OpLoc, diag::ext_typecheck_addrof_void) << op->getSourceRange(); 7722 } 7723 7724 // If the operand has type "type", the result has type "pointer to type". 7725 if (op->getType()->isObjCObjectType()) 7726 return S.Context.getObjCObjectPointerType(op->getType()); 7727 return S.Context.getPointerType(op->getType()); 7728} 7729 7730/// CheckIndirectionOperand - Type check unary indirection (prefix '*'). 7731static QualType CheckIndirectionOperand(Sema &S, Expr *Op, ExprValueKind &VK, 7732 SourceLocation OpLoc) { 7733 if (Op->isTypeDependent()) 7734 return S.Context.DependentTy; 7735 7736 ExprResult ConvResult = S.UsualUnaryConversions(Op); 7737 if (ConvResult.isInvalid()) 7738 return QualType(); 7739 Op = ConvResult.take(); 7740 QualType OpTy = Op->getType(); 7741 QualType Result; 7742 7743 if (isa<CXXReinterpretCastExpr>(Op)) { 7744 QualType OpOrigType = Op->IgnoreParenCasts()->getType(); 7745 S.CheckCompatibleReinterpretCast(OpOrigType, OpTy, /*IsDereference*/true, 7746 Op->getSourceRange()); 7747 } 7748 7749 // Note that per both C89 and C99, indirection is always legal, even if OpTy 7750 // is an incomplete type or void. It would be possible to warn about 7751 // dereferencing a void pointer, but it's completely well-defined, and such a 7752 // warning is unlikely to catch any mistakes. 7753 if (const PointerType *PT = OpTy->getAs<PointerType>()) 7754 Result = PT->getPointeeType(); 7755 else if (const ObjCObjectPointerType *OPT = 7756 OpTy->getAs<ObjCObjectPointerType>()) 7757 Result = OPT->getPointeeType(); 7758 else { 7759 ExprResult PR = S.CheckPlaceholderExpr(Op); 7760 if (PR.isInvalid()) return QualType(); 7761 if (PR.take() != Op) 7762 return CheckIndirectionOperand(S, PR.take(), VK, OpLoc); 7763 } 7764 7765 if (Result.isNull()) { 7766 S.Diag(OpLoc, diag::err_typecheck_indirection_requires_pointer) 7767 << OpTy << Op->getSourceRange(); 7768 return QualType(); 7769 } 7770 7771 // Dereferences are usually l-values... 7772 VK = VK_LValue; 7773 7774 // ...except that certain expressions are never l-values in C. 7775 if (!S.getLangOpts().CPlusPlus && Result.isCForbiddenLValueType()) 7776 VK = VK_RValue; 7777 7778 return Result; 7779} 7780 7781static inline BinaryOperatorKind ConvertTokenKindToBinaryOpcode( 7782 tok::TokenKind Kind) { 7783 BinaryOperatorKind Opc; 7784 switch (Kind) { 7785 default: llvm_unreachable("Unknown binop!"); 7786 case tok::periodstar: Opc = BO_PtrMemD; break; 7787 case tok::arrowstar: Opc = BO_PtrMemI; break; 7788 case tok::star: Opc = BO_Mul; break; 7789 case tok::slash: Opc = BO_Div; break; 7790 case tok::percent: Opc = BO_Rem; break; 7791 case tok::plus: Opc = BO_Add; break; 7792 case tok::minus: Opc = BO_Sub; break; 7793 case tok::lessless: Opc = BO_Shl; break; 7794 case tok::greatergreater: Opc = BO_Shr; break; 7795 case tok::lessequal: Opc = BO_LE; break; 7796 case tok::less: Opc = BO_LT; break; 7797 case tok::greaterequal: Opc = BO_GE; break; 7798 case tok::greater: Opc = BO_GT; break; 7799 case tok::exclaimequal: Opc = BO_NE; break; 7800 case tok::equalequal: Opc = BO_EQ; break; 7801 case tok::amp: Opc = BO_And; break; 7802 case tok::caret: Opc = BO_Xor; break; 7803 case tok::pipe: Opc = BO_Or; break; 7804 case tok::ampamp: Opc = BO_LAnd; break; 7805 case tok::pipepipe: Opc = BO_LOr; break; 7806 case tok::equal: Opc = BO_Assign; break; 7807 case tok::starequal: Opc = BO_MulAssign; break; 7808 case tok::slashequal: Opc = BO_DivAssign; break; 7809 case tok::percentequal: Opc = BO_RemAssign; break; 7810 case tok::plusequal: Opc = BO_AddAssign; break; 7811 case tok::minusequal: Opc = BO_SubAssign; break; 7812 case tok::lesslessequal: Opc = BO_ShlAssign; break; 7813 case tok::greatergreaterequal: Opc = BO_ShrAssign; break; 7814 case tok::ampequal: Opc = BO_AndAssign; break; 7815 case tok::caretequal: Opc = BO_XorAssign; break; 7816 case tok::pipeequal: Opc = BO_OrAssign; break; 7817 case tok::comma: Opc = BO_Comma; break; 7818 } 7819 return Opc; 7820} 7821 7822static inline UnaryOperatorKind ConvertTokenKindToUnaryOpcode( 7823 tok::TokenKind Kind) { 7824 UnaryOperatorKind Opc; 7825 switch (Kind) { 7826 default: llvm_unreachable("Unknown unary op!"); 7827 case tok::plusplus: Opc = UO_PreInc; break; 7828 case tok::minusminus: Opc = UO_PreDec; break; 7829 case tok::amp: Opc = UO_AddrOf; break; 7830 case tok::star: Opc = UO_Deref; break; 7831 case tok::plus: Opc = UO_Plus; break; 7832 case tok::minus: Opc = UO_Minus; break; 7833 case tok::tilde: Opc = UO_Not; break; 7834 case tok::exclaim: Opc = UO_LNot; break; 7835 case tok::kw___real: Opc = UO_Real; break; 7836 case tok::kw___imag: Opc = UO_Imag; break; 7837 case tok::kw___extension__: Opc = UO_Extension; break; 7838 } 7839 return Opc; 7840} 7841 7842/// DiagnoseSelfAssignment - Emits a warning if a value is assigned to itself. 7843/// This warning is only emitted for builtin assignment operations. It is also 7844/// suppressed in the event of macro expansions. 7845static void DiagnoseSelfAssignment(Sema &S, Expr *LHSExpr, Expr *RHSExpr, 7846 SourceLocation OpLoc) { 7847 if (!S.ActiveTemplateInstantiations.empty()) 7848 return; 7849 if (OpLoc.isInvalid() || OpLoc.isMacroID()) 7850 return; 7851 LHSExpr = LHSExpr->IgnoreParenImpCasts(); 7852 RHSExpr = RHSExpr->IgnoreParenImpCasts(); 7853 const DeclRefExpr *LHSDeclRef = dyn_cast<DeclRefExpr>(LHSExpr); 7854 const DeclRefExpr *RHSDeclRef = dyn_cast<DeclRefExpr>(RHSExpr); 7855 if (!LHSDeclRef || !RHSDeclRef || 7856 LHSDeclRef->getLocation().isMacroID() || 7857 RHSDeclRef->getLocation().isMacroID()) 7858 return; 7859 const ValueDecl *LHSDecl = 7860 cast<ValueDecl>(LHSDeclRef->getDecl()->getCanonicalDecl()); 7861 const ValueDecl *RHSDecl = 7862 cast<ValueDecl>(RHSDeclRef->getDecl()->getCanonicalDecl()); 7863 if (LHSDecl != RHSDecl) 7864 return; 7865 if (LHSDecl->getType().isVolatileQualified()) 7866 return; 7867 if (const ReferenceType *RefTy = LHSDecl->getType()->getAs<ReferenceType>()) 7868 if (RefTy->getPointeeType().isVolatileQualified()) 7869 return; 7870 7871 S.Diag(OpLoc, diag::warn_self_assignment) 7872 << LHSDeclRef->getType() 7873 << LHSExpr->getSourceRange() << RHSExpr->getSourceRange(); 7874} 7875 7876/// CreateBuiltinBinOp - Creates a new built-in binary operation with 7877/// operator @p Opc at location @c TokLoc. This routine only supports 7878/// built-in operations; ActOnBinOp handles overloaded operators. 7879ExprResult Sema::CreateBuiltinBinOp(SourceLocation OpLoc, 7880 BinaryOperatorKind Opc, 7881 Expr *LHSExpr, Expr *RHSExpr) { 7882 if (getLangOpts().CPlusPlus0x && isa<InitListExpr>(RHSExpr)) { 7883 // The syntax only allows initializer lists on the RHS of assignment, 7884 // so we don't need to worry about accepting invalid code for 7885 // non-assignment operators. 7886 // C++11 5.17p9: 7887 // The meaning of x = {v} [...] is that of x = T(v) [...]. The meaning 7888 // of x = {} is x = T(). 7889 InitializationKind Kind = 7890 InitializationKind::CreateDirectList(RHSExpr->getLocStart()); 7891 InitializedEntity Entity = 7892 InitializedEntity::InitializeTemporary(LHSExpr->getType()); 7893 InitializationSequence InitSeq(*this, Entity, Kind, &RHSExpr, 1); 7894 ExprResult Init = InitSeq.Perform(*this, Entity, Kind, 7895 MultiExprArg(&RHSExpr, 1)); 7896 if (Init.isInvalid()) 7897 return Init; 7898 RHSExpr = Init.take(); 7899 } 7900 7901 ExprResult LHS = Owned(LHSExpr), RHS = Owned(RHSExpr); 7902 QualType ResultTy; // Result type of the binary operator. 7903 // The following two variables are used for compound assignment operators 7904 QualType CompLHSTy; // Type of LHS after promotions for computation 7905 QualType CompResultTy; // Type of computation result 7906 ExprValueKind VK = VK_RValue; 7907 ExprObjectKind OK = OK_Ordinary; 7908 7909 switch (Opc) { 7910 case BO_Assign: 7911 ResultTy = CheckAssignmentOperands(LHS.get(), RHS, OpLoc, QualType()); 7912 if (getLangOpts().CPlusPlus && 7913 LHS.get()->getObjectKind() != OK_ObjCProperty) { 7914 VK = LHS.get()->getValueKind(); 7915 OK = LHS.get()->getObjectKind(); 7916 } 7917 if (!ResultTy.isNull()) 7918 DiagnoseSelfAssignment(*this, LHS.get(), RHS.get(), OpLoc); 7919 break; 7920 case BO_PtrMemD: 7921 case BO_PtrMemI: 7922 ResultTy = CheckPointerToMemberOperands(LHS, RHS, VK, OpLoc, 7923 Opc == BO_PtrMemI); 7924 break; 7925 case BO_Mul: 7926 case BO_Div: 7927 ResultTy = CheckMultiplyDivideOperands(LHS, RHS, OpLoc, false, 7928 Opc == BO_Div); 7929 break; 7930 case BO_Rem: 7931 ResultTy = CheckRemainderOperands(LHS, RHS, OpLoc); 7932 break; 7933 case BO_Add: 7934 ResultTy = CheckAdditionOperands(LHS, RHS, OpLoc, Opc); 7935 break; 7936 case BO_Sub: 7937 ResultTy = CheckSubtractionOperands(LHS, RHS, OpLoc); 7938 break; 7939 case BO_Shl: 7940 case BO_Shr: 7941 ResultTy = CheckShiftOperands(LHS, RHS, OpLoc, Opc); 7942 break; 7943 case BO_LE: 7944 case BO_LT: 7945 case BO_GE: 7946 case BO_GT: 7947 ResultTy = CheckCompareOperands(LHS, RHS, OpLoc, Opc, true); 7948 break; 7949 case BO_EQ: 7950 case BO_NE: 7951 ResultTy = CheckCompareOperands(LHS, RHS, OpLoc, Opc, false); 7952 break; 7953 case BO_And: 7954 case BO_Xor: 7955 case BO_Or: 7956 ResultTy = CheckBitwiseOperands(LHS, RHS, OpLoc); 7957 break; 7958 case BO_LAnd: 7959 case BO_LOr: 7960 ResultTy = CheckLogicalOperands(LHS, RHS, OpLoc, Opc); 7961 break; 7962 case BO_MulAssign: 7963 case BO_DivAssign: 7964 CompResultTy = CheckMultiplyDivideOperands(LHS, RHS, OpLoc, true, 7965 Opc == BO_DivAssign); 7966 CompLHSTy = CompResultTy; 7967 if (!CompResultTy.isNull() && !LHS.isInvalid() && !RHS.isInvalid()) 7968 ResultTy = CheckAssignmentOperands(LHS.get(), RHS, OpLoc, CompResultTy); 7969 break; 7970 case BO_RemAssign: 7971 CompResultTy = CheckRemainderOperands(LHS, RHS, OpLoc, true); 7972 CompLHSTy = CompResultTy; 7973 if (!CompResultTy.isNull() && !LHS.isInvalid() && !RHS.isInvalid()) 7974 ResultTy = CheckAssignmentOperands(LHS.get(), RHS, OpLoc, CompResultTy); 7975 break; 7976 case BO_AddAssign: 7977 CompResultTy = CheckAdditionOperands(LHS, RHS, OpLoc, Opc, &CompLHSTy); 7978 if (!CompResultTy.isNull() && !LHS.isInvalid() && !RHS.isInvalid()) 7979 ResultTy = CheckAssignmentOperands(LHS.get(), RHS, OpLoc, CompResultTy); 7980 break; 7981 case BO_SubAssign: 7982 CompResultTy = CheckSubtractionOperands(LHS, RHS, OpLoc, &CompLHSTy); 7983 if (!CompResultTy.isNull() && !LHS.isInvalid() && !RHS.isInvalid()) 7984 ResultTy = CheckAssignmentOperands(LHS.get(), RHS, OpLoc, CompResultTy); 7985 break; 7986 case BO_ShlAssign: 7987 case BO_ShrAssign: 7988 CompResultTy = CheckShiftOperands(LHS, RHS, OpLoc, Opc, true); 7989 CompLHSTy = CompResultTy; 7990 if (!CompResultTy.isNull() && !LHS.isInvalid() && !RHS.isInvalid()) 7991 ResultTy = CheckAssignmentOperands(LHS.get(), RHS, OpLoc, CompResultTy); 7992 break; 7993 case BO_AndAssign: 7994 case BO_XorAssign: 7995 case BO_OrAssign: 7996 CompResultTy = CheckBitwiseOperands(LHS, RHS, OpLoc, true); 7997 CompLHSTy = CompResultTy; 7998 if (!CompResultTy.isNull() && !LHS.isInvalid() && !RHS.isInvalid()) 7999 ResultTy = CheckAssignmentOperands(LHS.get(), RHS, OpLoc, CompResultTy); 8000 break; 8001 case BO_Comma: 8002 ResultTy = CheckCommaOperands(*this, LHS, RHS, OpLoc); 8003 if (getLangOpts().CPlusPlus && !RHS.isInvalid()) { 8004 VK = RHS.get()->getValueKind(); 8005 OK = RHS.get()->getObjectKind(); 8006 } 8007 break; 8008 } 8009 if (ResultTy.isNull() || LHS.isInvalid() || RHS.isInvalid()) 8010 return ExprError(); 8011 8012 // Check for array bounds violations for both sides of the BinaryOperator 8013 CheckArrayAccess(LHS.get()); 8014 CheckArrayAccess(RHS.get()); 8015 8016 if (CompResultTy.isNull()) 8017 return Owned(new (Context) BinaryOperator(LHS.take(), RHS.take(), Opc, 8018 ResultTy, VK, OK, OpLoc)); 8019 if (getLangOpts().CPlusPlus && LHS.get()->getObjectKind() != 8020 OK_ObjCProperty) { 8021 VK = VK_LValue; 8022 OK = LHS.get()->getObjectKind(); 8023 } 8024 return Owned(new (Context) CompoundAssignOperator(LHS.take(), RHS.take(), Opc, 8025 ResultTy, VK, OK, CompLHSTy, 8026 CompResultTy, OpLoc)); 8027} 8028 8029/// DiagnoseBitwisePrecedence - Emit a warning when bitwise and comparison 8030/// operators are mixed in a way that suggests that the programmer forgot that 8031/// comparison operators have higher precedence. The most typical example of 8032/// such code is "flags & 0x0020 != 0", which is equivalent to "flags & 1". 8033static void DiagnoseBitwisePrecedence(Sema &Self, BinaryOperatorKind Opc, 8034 SourceLocation OpLoc, Expr *LHSExpr, 8035 Expr *RHSExpr) { 8036 typedef BinaryOperator BinOp; 8037 BinOp::Opcode LHSopc = static_cast<BinOp::Opcode>(-1), 8038 RHSopc = static_cast<BinOp::Opcode>(-1); 8039 if (BinOp *BO = dyn_cast<BinOp>(LHSExpr)) 8040 LHSopc = BO->getOpcode(); 8041 if (BinOp *BO = dyn_cast<BinOp>(RHSExpr)) 8042 RHSopc = BO->getOpcode(); 8043 8044 // Subs are not binary operators. 8045 if (LHSopc == -1 && RHSopc == -1) 8046 return; 8047 8048 // Bitwise operations are sometimes used as eager logical ops. 8049 // Don't diagnose this. 8050 if ((BinOp::isComparisonOp(LHSopc) || BinOp::isBitwiseOp(LHSopc)) && 8051 (BinOp::isComparisonOp(RHSopc) || BinOp::isBitwiseOp(RHSopc))) 8052 return; 8053 8054 bool isLeftComp = BinOp::isComparisonOp(LHSopc); 8055 bool isRightComp = BinOp::isComparisonOp(RHSopc); 8056 if (!isLeftComp && !isRightComp) return; 8057 8058 SourceRange DiagRange = isLeftComp ? SourceRange(LHSExpr->getLocStart(), 8059 OpLoc) 8060 : SourceRange(OpLoc, RHSExpr->getLocEnd()); 8061 std::string OpStr = isLeftComp ? BinOp::getOpcodeStr(LHSopc) 8062 : BinOp::getOpcodeStr(RHSopc); 8063 SourceRange ParensRange = isLeftComp ? 8064 SourceRange(cast<BinOp>(LHSExpr)->getRHS()->getLocStart(), 8065 RHSExpr->getLocEnd()) 8066 : SourceRange(LHSExpr->getLocStart(), 8067 cast<BinOp>(RHSExpr)->getLHS()->getLocStart()); 8068 8069 Self.Diag(OpLoc, diag::warn_precedence_bitwise_rel) 8070 << DiagRange << BinOp::getOpcodeStr(Opc) << OpStr; 8071 SuggestParentheses(Self, OpLoc, 8072 Self.PDiag(diag::note_precedence_bitwise_silence) << OpStr, 8073 RHSExpr->getSourceRange()); 8074 SuggestParentheses(Self, OpLoc, 8075 Self.PDiag(diag::note_precedence_bitwise_first) << BinOp::getOpcodeStr(Opc), 8076 ParensRange); 8077} 8078 8079/// \brief It accepts a '&' expr that is inside a '|' one. 8080/// Emit a diagnostic together with a fixit hint that wraps the '&' expression 8081/// in parentheses. 8082static void 8083EmitDiagnosticForBitwiseAndInBitwiseOr(Sema &Self, SourceLocation OpLoc, 8084 BinaryOperator *Bop) { 8085 assert(Bop->getOpcode() == BO_And); 8086 Self.Diag(Bop->getOperatorLoc(), diag::warn_bitwise_and_in_bitwise_or) 8087 << Bop->getSourceRange() << OpLoc; 8088 SuggestParentheses(Self, Bop->getOperatorLoc(), 8089 Self.PDiag(diag::note_bitwise_and_in_bitwise_or_silence), 8090 Bop->getSourceRange()); 8091} 8092 8093/// \brief It accepts a '&&' expr that is inside a '||' one. 8094/// Emit a diagnostic together with a fixit hint that wraps the '&&' expression 8095/// in parentheses. 8096static void 8097EmitDiagnosticForLogicalAndInLogicalOr(Sema &Self, SourceLocation OpLoc, 8098 BinaryOperator *Bop) { 8099 assert(Bop->getOpcode() == BO_LAnd); 8100 Self.Diag(Bop->getOperatorLoc(), diag::warn_logical_and_in_logical_or) 8101 << Bop->getSourceRange() << OpLoc; 8102 SuggestParentheses(Self, Bop->getOperatorLoc(), 8103 Self.PDiag(diag::note_logical_and_in_logical_or_silence), 8104 Bop->getSourceRange()); 8105} 8106 8107/// \brief Returns true if the given expression can be evaluated as a constant 8108/// 'true'. 8109static bool EvaluatesAsTrue(Sema &S, Expr *E) { 8110 bool Res; 8111 return E->EvaluateAsBooleanCondition(Res, S.getASTContext()) && Res; 8112} 8113 8114/// \brief Returns true if the given expression can be evaluated as a constant 8115/// 'false'. 8116static bool EvaluatesAsFalse(Sema &S, Expr *E) { 8117 bool Res; 8118 return E->EvaluateAsBooleanCondition(Res, S.getASTContext()) && !Res; 8119} 8120 8121/// \brief Look for '&&' in the left hand of a '||' expr. 8122static void DiagnoseLogicalAndInLogicalOrLHS(Sema &S, SourceLocation OpLoc, 8123 Expr *LHSExpr, Expr *RHSExpr) { 8124 if (BinaryOperator *Bop = dyn_cast<BinaryOperator>(LHSExpr)) { 8125 if (Bop->getOpcode() == BO_LAnd) { 8126 // If it's "a && b || 0" don't warn since the precedence doesn't matter. 8127 if (EvaluatesAsFalse(S, RHSExpr)) 8128 return; 8129 // If it's "1 && a || b" don't warn since the precedence doesn't matter. 8130 if (!EvaluatesAsTrue(S, Bop->getLHS())) 8131 return EmitDiagnosticForLogicalAndInLogicalOr(S, OpLoc, Bop); 8132 } else if (Bop->getOpcode() == BO_LOr) { 8133 if (BinaryOperator *RBop = dyn_cast<BinaryOperator>(Bop->getRHS())) { 8134 // If it's "a || b && 1 || c" we didn't warn earlier for 8135 // "a || b && 1", but warn now. 8136 if (RBop->getOpcode() == BO_LAnd && EvaluatesAsTrue(S, RBop->getRHS())) 8137 return EmitDiagnosticForLogicalAndInLogicalOr(S, OpLoc, RBop); 8138 } 8139 } 8140 } 8141} 8142 8143/// \brief Look for '&&' in the right hand of a '||' expr. 8144static void DiagnoseLogicalAndInLogicalOrRHS(Sema &S, SourceLocation OpLoc, 8145 Expr *LHSExpr, Expr *RHSExpr) { 8146 if (BinaryOperator *Bop = dyn_cast<BinaryOperator>(RHSExpr)) { 8147 if (Bop->getOpcode() == BO_LAnd) { 8148 // If it's "0 || a && b" don't warn since the precedence doesn't matter. 8149 if (EvaluatesAsFalse(S, LHSExpr)) 8150 return; 8151 // If it's "a || b && 1" don't warn since the precedence doesn't matter. 8152 if (!EvaluatesAsTrue(S, Bop->getRHS())) 8153 return EmitDiagnosticForLogicalAndInLogicalOr(S, OpLoc, Bop); 8154 } 8155 } 8156} 8157 8158/// \brief Look for '&' in the left or right hand of a '|' expr. 8159static void DiagnoseBitwiseAndInBitwiseOr(Sema &S, SourceLocation OpLoc, 8160 Expr *OrArg) { 8161 if (BinaryOperator *Bop = dyn_cast<BinaryOperator>(OrArg)) { 8162 if (Bop->getOpcode() == BO_And) 8163 return EmitDiagnosticForBitwiseAndInBitwiseOr(S, OpLoc, Bop); 8164 } 8165} 8166 8167/// DiagnoseBinOpPrecedence - Emit warnings for expressions with tricky 8168/// precedence. 8169static void DiagnoseBinOpPrecedence(Sema &Self, BinaryOperatorKind Opc, 8170 SourceLocation OpLoc, Expr *LHSExpr, 8171 Expr *RHSExpr){ 8172 // Diagnose "arg1 'bitwise' arg2 'eq' arg3". 8173 if (BinaryOperator::isBitwiseOp(Opc)) 8174 DiagnoseBitwisePrecedence(Self, Opc, OpLoc, LHSExpr, RHSExpr); 8175 8176 // Diagnose "arg1 & arg2 | arg3" 8177 if (Opc == BO_Or && !OpLoc.isMacroID()/* Don't warn in macros. */) { 8178 DiagnoseBitwiseAndInBitwiseOr(Self, OpLoc, LHSExpr); 8179 DiagnoseBitwiseAndInBitwiseOr(Self, OpLoc, RHSExpr); 8180 } 8181 8182 // Warn about arg1 || arg2 && arg3, as GCC 4.3+ does. 8183 // We don't warn for 'assert(a || b && "bad")' since this is safe. 8184 if (Opc == BO_LOr && !OpLoc.isMacroID()/* Don't warn in macros. */) { 8185 DiagnoseLogicalAndInLogicalOrLHS(Self, OpLoc, LHSExpr, RHSExpr); 8186 DiagnoseLogicalAndInLogicalOrRHS(Self, OpLoc, LHSExpr, RHSExpr); 8187 } 8188} 8189 8190// Binary Operators. 'Tok' is the token for the operator. 8191ExprResult Sema::ActOnBinOp(Scope *S, SourceLocation TokLoc, 8192 tok::TokenKind Kind, 8193 Expr *LHSExpr, Expr *RHSExpr) { 8194 BinaryOperatorKind Opc = ConvertTokenKindToBinaryOpcode(Kind); 8195 assert((LHSExpr != 0) && "ActOnBinOp(): missing left expression"); 8196 assert((RHSExpr != 0) && "ActOnBinOp(): missing right expression"); 8197 8198 // Emit warnings for tricky precedence issues, e.g. "bitfield & 0x4 == 0" 8199 DiagnoseBinOpPrecedence(*this, Opc, TokLoc, LHSExpr, RHSExpr); 8200 8201 return BuildBinOp(S, TokLoc, Opc, LHSExpr, RHSExpr); 8202} 8203 8204/// Build an overloaded binary operator expression in the given scope. 8205static ExprResult BuildOverloadedBinOp(Sema &S, Scope *Sc, SourceLocation OpLoc, 8206 BinaryOperatorKind Opc, 8207 Expr *LHS, Expr *RHS) { 8208 // Find all of the overloaded operators visible from this 8209 // point. We perform both an operator-name lookup from the local 8210 // scope and an argument-dependent lookup based on the types of 8211 // the arguments. 8212 UnresolvedSet<16> Functions; 8213 OverloadedOperatorKind OverOp 8214 = BinaryOperator::getOverloadedOperator(Opc); 8215 if (Sc && OverOp != OO_None) 8216 S.LookupOverloadedOperatorName(OverOp, Sc, LHS->getType(), 8217 RHS->getType(), Functions); 8218 8219 // Build the (potentially-overloaded, potentially-dependent) 8220 // binary operation. 8221 return S.CreateOverloadedBinOp(OpLoc, Opc, Functions, LHS, RHS); 8222} 8223 8224ExprResult Sema::BuildBinOp(Scope *S, SourceLocation OpLoc, 8225 BinaryOperatorKind Opc, 8226 Expr *LHSExpr, Expr *RHSExpr) { 8227 // We want to end up calling one of checkPseudoObjectAssignment 8228 // (if the LHS is a pseudo-object), BuildOverloadedBinOp (if 8229 // both expressions are overloadable or either is type-dependent), 8230 // or CreateBuiltinBinOp (in any other case). We also want to get 8231 // any placeholder types out of the way. 8232 8233 // Handle pseudo-objects in the LHS. 8234 if (const BuiltinType *pty = LHSExpr->getType()->getAsPlaceholderType()) { 8235 // Assignments with a pseudo-object l-value need special analysis. 8236 if (pty->getKind() == BuiltinType::PseudoObject && 8237 BinaryOperator::isAssignmentOp(Opc)) 8238 return checkPseudoObjectAssignment(S, OpLoc, Opc, LHSExpr, RHSExpr); 8239 8240 // Don't resolve overloads if the other type is overloadable. 8241 if (pty->getKind() == BuiltinType::Overload) { 8242 // We can't actually test that if we still have a placeholder, 8243 // though. Fortunately, none of the exceptions we see in that 8244 // code below are valid when the LHS is an overload set. Note 8245 // that an overload set can be dependently-typed, but it never 8246 // instantiates to having an overloadable type. 8247 ExprResult resolvedRHS = CheckPlaceholderExpr(RHSExpr); 8248 if (resolvedRHS.isInvalid()) return ExprError(); 8249 RHSExpr = resolvedRHS.take(); 8250 8251 if (RHSExpr->isTypeDependent() || 8252 RHSExpr->getType()->isOverloadableType()) 8253 return BuildOverloadedBinOp(*this, S, OpLoc, Opc, LHSExpr, RHSExpr); 8254 } 8255 8256 ExprResult LHS = CheckPlaceholderExpr(LHSExpr); 8257 if (LHS.isInvalid()) return ExprError(); 8258 LHSExpr = LHS.take(); 8259 } 8260 8261 // Handle pseudo-objects in the RHS. 8262 if (const BuiltinType *pty = RHSExpr->getType()->getAsPlaceholderType()) { 8263 // An overload in the RHS can potentially be resolved by the type 8264 // being assigned to. 8265 if (Opc == BO_Assign && pty->getKind() == BuiltinType::Overload) { 8266 if (LHSExpr->isTypeDependent() || RHSExpr->isTypeDependent()) 8267 return BuildOverloadedBinOp(*this, S, OpLoc, Opc, LHSExpr, RHSExpr); 8268 8269 if (LHSExpr->getType()->isOverloadableType()) 8270 return BuildOverloadedBinOp(*this, S, OpLoc, Opc, LHSExpr, RHSExpr); 8271 8272 return CreateBuiltinBinOp(OpLoc, Opc, LHSExpr, RHSExpr); 8273 } 8274 8275 // Don't resolve overloads if the other type is overloadable. 8276 if (pty->getKind() == BuiltinType::Overload && 8277 LHSExpr->getType()->isOverloadableType()) 8278 return BuildOverloadedBinOp(*this, S, OpLoc, Opc, LHSExpr, RHSExpr); 8279 8280 ExprResult resolvedRHS = CheckPlaceholderExpr(RHSExpr); 8281 if (!resolvedRHS.isUsable()) return ExprError(); 8282 RHSExpr = resolvedRHS.take(); 8283 } 8284 8285 if (getLangOpts().CPlusPlus) { 8286 // If either expression is type-dependent, always build an 8287 // overloaded op. 8288 if (LHSExpr->isTypeDependent() || RHSExpr->isTypeDependent()) 8289 return BuildOverloadedBinOp(*this, S, OpLoc, Opc, LHSExpr, RHSExpr); 8290 8291 // Otherwise, build an overloaded op if either expression has an 8292 // overloadable type. 8293 if (LHSExpr->getType()->isOverloadableType() || 8294 RHSExpr->getType()->isOverloadableType()) 8295 return BuildOverloadedBinOp(*this, S, OpLoc, Opc, LHSExpr, RHSExpr); 8296 } 8297 8298 // Build a built-in binary operation. 8299 return CreateBuiltinBinOp(OpLoc, Opc, LHSExpr, RHSExpr); 8300} 8301 8302ExprResult Sema::CreateBuiltinUnaryOp(SourceLocation OpLoc, 8303 UnaryOperatorKind Opc, 8304 Expr *InputExpr) { 8305 ExprResult Input = Owned(InputExpr); 8306 ExprValueKind VK = VK_RValue; 8307 ExprObjectKind OK = OK_Ordinary; 8308 QualType resultType; 8309 switch (Opc) { 8310 case UO_PreInc: 8311 case UO_PreDec: 8312 case UO_PostInc: 8313 case UO_PostDec: 8314 resultType = CheckIncrementDecrementOperand(*this, Input.get(), VK, OpLoc, 8315 Opc == UO_PreInc || 8316 Opc == UO_PostInc, 8317 Opc == UO_PreInc || 8318 Opc == UO_PreDec); 8319 break; 8320 case UO_AddrOf: 8321 resultType = CheckAddressOfOperand(*this, Input, OpLoc); 8322 break; 8323 case UO_Deref: { 8324 Input = DefaultFunctionArrayLvalueConversion(Input.take()); 8325 resultType = CheckIndirectionOperand(*this, Input.get(), VK, OpLoc); 8326 break; 8327 } 8328 case UO_Plus: 8329 case UO_Minus: 8330 Input = UsualUnaryConversions(Input.take()); 8331 if (Input.isInvalid()) return ExprError(); 8332 resultType = Input.get()->getType(); 8333 if (resultType->isDependentType()) 8334 break; 8335 if (resultType->isArithmeticType() || // C99 6.5.3.3p1 8336 resultType->isVectorType()) 8337 break; 8338 else if (getLangOpts().CPlusPlus && // C++ [expr.unary.op]p6-7 8339 resultType->isEnumeralType()) 8340 break; 8341 else if (getLangOpts().CPlusPlus && // C++ [expr.unary.op]p6 8342 Opc == UO_Plus && 8343 resultType->isPointerType()) 8344 break; 8345 8346 return ExprError(Diag(OpLoc, diag::err_typecheck_unary_expr) 8347 << resultType << Input.get()->getSourceRange()); 8348 8349 case UO_Not: // bitwise complement 8350 Input = UsualUnaryConversions(Input.take()); 8351 if (Input.isInvalid()) return ExprError(); 8352 resultType = Input.get()->getType(); 8353 if (resultType->isDependentType()) 8354 break; 8355 // C99 6.5.3.3p1. We allow complex int and float as a GCC extension. 8356 if (resultType->isComplexType() || resultType->isComplexIntegerType()) 8357 // C99 does not support '~' for complex conjugation. 8358 Diag(OpLoc, diag::ext_integer_complement_complex) 8359 << resultType << Input.get()->getSourceRange(); 8360 else if (resultType->hasIntegerRepresentation()) 8361 break; 8362 else { 8363 return ExprError(Diag(OpLoc, diag::err_typecheck_unary_expr) 8364 << resultType << Input.get()->getSourceRange()); 8365 } 8366 break; 8367 8368 case UO_LNot: // logical negation 8369 // Unlike +/-/~, integer promotions aren't done here (C99 6.5.3.3p5). 8370 Input = DefaultFunctionArrayLvalueConversion(Input.take()); 8371 if (Input.isInvalid()) return ExprError(); 8372 resultType = Input.get()->getType(); 8373 8374 // Though we still have to promote half FP to float... 8375 if (resultType->isHalfType()) { 8376 Input = ImpCastExprToType(Input.take(), Context.FloatTy, CK_FloatingCast).take(); 8377 resultType = Context.FloatTy; 8378 } 8379 8380 if (resultType->isDependentType()) 8381 break; 8382 if (resultType->isScalarType()) { 8383 // C99 6.5.3.3p1: ok, fallthrough; 8384 if (Context.getLangOpts().CPlusPlus) { 8385 // C++03 [expr.unary.op]p8, C++0x [expr.unary.op]p9: 8386 // operand contextually converted to bool. 8387 Input = ImpCastExprToType(Input.take(), Context.BoolTy, 8388 ScalarTypeToBooleanCastKind(resultType)); 8389 } 8390 } else if (resultType->isExtVectorType()) { 8391 // Vector logical not returns the signed variant of the operand type. 8392 resultType = GetSignedVectorType(resultType); 8393 break; 8394 } else { 8395 return ExprError(Diag(OpLoc, diag::err_typecheck_unary_expr) 8396 << resultType << Input.get()->getSourceRange()); 8397 } 8398 8399 // LNot always has type int. C99 6.5.3.3p5. 8400 // In C++, it's bool. C++ 5.3.1p8 8401 resultType = Context.getLogicalOperationType(); 8402 break; 8403 case UO_Real: 8404 case UO_Imag: 8405 resultType = CheckRealImagOperand(*this, Input, OpLoc, Opc == UO_Real); 8406 // _Real maps ordinary l-values into ordinary l-values. _Imag maps ordinary 8407 // complex l-values to ordinary l-values and all other values to r-values. 8408 if (Input.isInvalid()) return ExprError(); 8409 if (Opc == UO_Real || Input.get()->getType()->isAnyComplexType()) { 8410 if (Input.get()->getValueKind() != VK_RValue && 8411 Input.get()->getObjectKind() == OK_Ordinary) 8412 VK = Input.get()->getValueKind(); 8413 } else if (!getLangOpts().CPlusPlus) { 8414 // In C, a volatile scalar is read by __imag. In C++, it is not. 8415 Input = DefaultLvalueConversion(Input.take()); 8416 } 8417 break; 8418 case UO_Extension: 8419 resultType = Input.get()->getType(); 8420 VK = Input.get()->getValueKind(); 8421 OK = Input.get()->getObjectKind(); 8422 break; 8423 } 8424 if (resultType.isNull() || Input.isInvalid()) 8425 return ExprError(); 8426 8427 // Check for array bounds violations in the operand of the UnaryOperator, 8428 // except for the '*' and '&' operators that have to be handled specially 8429 // by CheckArrayAccess (as there are special cases like &array[arraysize] 8430 // that are explicitly defined as valid by the standard). 8431 if (Opc != UO_AddrOf && Opc != UO_Deref) 8432 CheckArrayAccess(Input.get()); 8433 8434 return Owned(new (Context) UnaryOperator(Input.take(), Opc, resultType, 8435 VK, OK, OpLoc)); 8436} 8437 8438/// \brief Determine whether the given expression is a qualified member 8439/// access expression, of a form that could be turned into a pointer to member 8440/// with the address-of operator. 8441static bool isQualifiedMemberAccess(Expr *E) { 8442 if (DeclRefExpr *DRE = dyn_cast<DeclRefExpr>(E)) { 8443 if (!DRE->getQualifier()) 8444 return false; 8445 8446 ValueDecl *VD = DRE->getDecl(); 8447 if (!VD->isCXXClassMember()) 8448 return false; 8449 8450 if (isa<FieldDecl>(VD) || isa<IndirectFieldDecl>(VD)) 8451 return true; 8452 if (CXXMethodDecl *Method = dyn_cast<CXXMethodDecl>(VD)) 8453 return Method->isInstance(); 8454 8455 return false; 8456 } 8457 8458 if (UnresolvedLookupExpr *ULE = dyn_cast<UnresolvedLookupExpr>(E)) { 8459 if (!ULE->getQualifier()) 8460 return false; 8461 8462 for (UnresolvedLookupExpr::decls_iterator D = ULE->decls_begin(), 8463 DEnd = ULE->decls_end(); 8464 D != DEnd; ++D) { 8465 if (CXXMethodDecl *Method = dyn_cast<CXXMethodDecl>(*D)) { 8466 if (Method->isInstance()) 8467 return true; 8468 } else { 8469 // Overload set does not contain methods. 8470 break; 8471 } 8472 } 8473 8474 return false; 8475 } 8476 8477 return false; 8478} 8479 8480ExprResult Sema::BuildUnaryOp(Scope *S, SourceLocation OpLoc, 8481 UnaryOperatorKind Opc, Expr *Input) { 8482 // First things first: handle placeholders so that the 8483 // overloaded-operator check considers the right type. 8484 if (const BuiltinType *pty = Input->getType()->getAsPlaceholderType()) { 8485 // Increment and decrement of pseudo-object references. 8486 if (pty->getKind() == BuiltinType::PseudoObject && 8487 UnaryOperator::isIncrementDecrementOp(Opc)) 8488 return checkPseudoObjectIncDec(S, OpLoc, Opc, Input); 8489 8490 // extension is always a builtin operator. 8491 if (Opc == UO_Extension) 8492 return CreateBuiltinUnaryOp(OpLoc, Opc, Input); 8493 8494 // & gets special logic for several kinds of placeholder. 8495 // The builtin code knows what to do. 8496 if (Opc == UO_AddrOf && 8497 (pty->getKind() == BuiltinType::Overload || 8498 pty->getKind() == BuiltinType::UnknownAny || 8499 pty->getKind() == BuiltinType::BoundMember)) 8500 return CreateBuiltinUnaryOp(OpLoc, Opc, Input); 8501 8502 // Anything else needs to be handled now. 8503 ExprResult Result = CheckPlaceholderExpr(Input); 8504 if (Result.isInvalid()) return ExprError(); 8505 Input = Result.take(); 8506 } 8507 8508 if (getLangOpts().CPlusPlus && Input->getType()->isOverloadableType() && 8509 UnaryOperator::getOverloadedOperator(Opc) != OO_None && 8510 !(Opc == UO_AddrOf && isQualifiedMemberAccess(Input))) { 8511 // Find all of the overloaded operators visible from this 8512 // point. We perform both an operator-name lookup from the local 8513 // scope and an argument-dependent lookup based on the types of 8514 // the arguments. 8515 UnresolvedSet<16> Functions; 8516 OverloadedOperatorKind OverOp = UnaryOperator::getOverloadedOperator(Opc); 8517 if (S && OverOp != OO_None) 8518 LookupOverloadedOperatorName(OverOp, S, Input->getType(), QualType(), 8519 Functions); 8520 8521 return CreateOverloadedUnaryOp(OpLoc, Opc, Functions, Input); 8522 } 8523 8524 return CreateBuiltinUnaryOp(OpLoc, Opc, Input); 8525} 8526 8527// Unary Operators. 'Tok' is the token for the operator. 8528ExprResult Sema::ActOnUnaryOp(Scope *S, SourceLocation OpLoc, 8529 tok::TokenKind Op, Expr *Input) { 8530 return BuildUnaryOp(S, OpLoc, ConvertTokenKindToUnaryOpcode(Op), Input); 8531} 8532 8533/// ActOnAddrLabel - Parse the GNU address of label extension: "&&foo". 8534ExprResult Sema::ActOnAddrLabel(SourceLocation OpLoc, SourceLocation LabLoc, 8535 LabelDecl *TheDecl) { 8536 TheDecl->setUsed(); 8537 // Create the AST node. The address of a label always has type 'void*'. 8538 return Owned(new (Context) AddrLabelExpr(OpLoc, LabLoc, TheDecl, 8539 Context.getPointerType(Context.VoidTy))); 8540} 8541 8542/// Given the last statement in a statement-expression, check whether 8543/// the result is a producing expression (like a call to an 8544/// ns_returns_retained function) and, if so, rebuild it to hoist the 8545/// release out of the full-expression. Otherwise, return null. 8546/// Cannot fail. 8547static Expr *maybeRebuildARCConsumingStmt(Stmt *Statement) { 8548 // Should always be wrapped with one of these. 8549 ExprWithCleanups *cleanups = dyn_cast<ExprWithCleanups>(Statement); 8550 if (!cleanups) return 0; 8551 8552 ImplicitCastExpr *cast = dyn_cast<ImplicitCastExpr>(cleanups->getSubExpr()); 8553 if (!cast || cast->getCastKind() != CK_ARCConsumeObject) 8554 return 0; 8555 8556 // Splice out the cast. This shouldn't modify any interesting 8557 // features of the statement. 8558 Expr *producer = cast->getSubExpr(); 8559 assert(producer->getType() == cast->getType()); 8560 assert(producer->getValueKind() == cast->getValueKind()); 8561 cleanups->setSubExpr(producer); 8562 return cleanups; 8563} 8564 8565void Sema::ActOnStartStmtExpr() { 8566 PushExpressionEvaluationContext(ExprEvalContexts.back().Context); 8567} 8568 8569void Sema::ActOnStmtExprError() { 8570 // Note that function is also called by TreeTransform when leaving a 8571 // StmtExpr scope without rebuilding anything. 8572 8573 DiscardCleanupsInEvaluationContext(); 8574 PopExpressionEvaluationContext(); 8575} 8576 8577ExprResult 8578Sema::ActOnStmtExpr(SourceLocation LPLoc, Stmt *SubStmt, 8579 SourceLocation RPLoc) { // "({..})" 8580 assert(SubStmt && isa<CompoundStmt>(SubStmt) && "Invalid action invocation!"); 8581 CompoundStmt *Compound = cast<CompoundStmt>(SubStmt); 8582 8583 if (hasAnyUnrecoverableErrorsInThisFunction()) 8584 DiscardCleanupsInEvaluationContext(); 8585 assert(!ExprNeedsCleanups && "cleanups within StmtExpr not correctly bound!"); 8586 PopExpressionEvaluationContext(); 8587 8588 bool isFileScope 8589 = (getCurFunctionOrMethodDecl() == 0) && (getCurBlock() == 0); 8590 if (isFileScope) 8591 return ExprError(Diag(LPLoc, diag::err_stmtexpr_file_scope)); 8592 8593 // FIXME: there are a variety of strange constraints to enforce here, for 8594 // example, it is not possible to goto into a stmt expression apparently. 8595 // More semantic analysis is needed. 8596 8597 // If there are sub stmts in the compound stmt, take the type of the last one 8598 // as the type of the stmtexpr. 8599 QualType Ty = Context.VoidTy; 8600 bool StmtExprMayBindToTemp = false; 8601 if (!Compound->body_empty()) { 8602 Stmt *LastStmt = Compound->body_back(); 8603 LabelStmt *LastLabelStmt = 0; 8604 // If LastStmt is a label, skip down through into the body. 8605 while (LabelStmt *Label = dyn_cast<LabelStmt>(LastStmt)) { 8606 LastLabelStmt = Label; 8607 LastStmt = Label->getSubStmt(); 8608 } 8609 8610 if (Expr *LastE = dyn_cast<Expr>(LastStmt)) { 8611 // Do function/array conversion on the last expression, but not 8612 // lvalue-to-rvalue. However, initialize an unqualified type. 8613 ExprResult LastExpr = DefaultFunctionArrayConversion(LastE); 8614 if (LastExpr.isInvalid()) 8615 return ExprError(); 8616 Ty = LastExpr.get()->getType().getUnqualifiedType(); 8617 8618 if (!Ty->isDependentType() && !LastExpr.get()->isTypeDependent()) { 8619 // In ARC, if the final expression ends in a consume, splice 8620 // the consume out and bind it later. In the alternate case 8621 // (when dealing with a retainable type), the result 8622 // initialization will create a produce. In both cases the 8623 // result will be +1, and we'll need to balance that out with 8624 // a bind. 8625 if (Expr *rebuiltLastStmt 8626 = maybeRebuildARCConsumingStmt(LastExpr.get())) { 8627 LastExpr = rebuiltLastStmt; 8628 } else { 8629 LastExpr = PerformCopyInitialization( 8630 InitializedEntity::InitializeResult(LPLoc, 8631 Ty, 8632 false), 8633 SourceLocation(), 8634 LastExpr); 8635 } 8636 8637 if (LastExpr.isInvalid()) 8638 return ExprError(); 8639 if (LastExpr.get() != 0) { 8640 if (!LastLabelStmt) 8641 Compound->setLastStmt(LastExpr.take()); 8642 else 8643 LastLabelStmt->setSubStmt(LastExpr.take()); 8644 StmtExprMayBindToTemp = true; 8645 } 8646 } 8647 } 8648 } 8649 8650 // FIXME: Check that expression type is complete/non-abstract; statement 8651 // expressions are not lvalues. 8652 Expr *ResStmtExpr = new (Context) StmtExpr(Compound, Ty, LPLoc, RPLoc); 8653 if (StmtExprMayBindToTemp) 8654 return MaybeBindToTemporary(ResStmtExpr); 8655 return Owned(ResStmtExpr); 8656} 8657 8658ExprResult Sema::BuildBuiltinOffsetOf(SourceLocation BuiltinLoc, 8659 TypeSourceInfo *TInfo, 8660 OffsetOfComponent *CompPtr, 8661 unsigned NumComponents, 8662 SourceLocation RParenLoc) { 8663 QualType ArgTy = TInfo->getType(); 8664 bool Dependent = ArgTy->isDependentType(); 8665 SourceRange TypeRange = TInfo->getTypeLoc().getLocalSourceRange(); 8666 8667 // We must have at least one component that refers to the type, and the first 8668 // one is known to be a field designator. Verify that the ArgTy represents 8669 // a struct/union/class. 8670 if (!Dependent && !ArgTy->isRecordType()) 8671 return ExprError(Diag(BuiltinLoc, diag::err_offsetof_record_type) 8672 << ArgTy << TypeRange); 8673 8674 // Type must be complete per C99 7.17p3 because a declaring a variable 8675 // with an incomplete type would be ill-formed. 8676 if (!Dependent 8677 && RequireCompleteType(BuiltinLoc, ArgTy, 8678 PDiag(diag::err_offsetof_incomplete_type) 8679 << TypeRange)) 8680 return ExprError(); 8681 8682 // offsetof with non-identifier designators (e.g. "offsetof(x, a.b[c])") are a 8683 // GCC extension, diagnose them. 8684 // FIXME: This diagnostic isn't actually visible because the location is in 8685 // a system header! 8686 if (NumComponents != 1) 8687 Diag(BuiltinLoc, diag::ext_offsetof_extended_field_designator) 8688 << SourceRange(CompPtr[1].LocStart, CompPtr[NumComponents-1].LocEnd); 8689 8690 bool DidWarnAboutNonPOD = false; 8691 QualType CurrentType = ArgTy; 8692 typedef OffsetOfExpr::OffsetOfNode OffsetOfNode; 8693 SmallVector<OffsetOfNode, 4> Comps; 8694 SmallVector<Expr*, 4> Exprs; 8695 for (unsigned i = 0; i != NumComponents; ++i) { 8696 const OffsetOfComponent &OC = CompPtr[i]; 8697 if (OC.isBrackets) { 8698 // Offset of an array sub-field. TODO: Should we allow vector elements? 8699 if (!CurrentType->isDependentType()) { 8700 const ArrayType *AT = Context.getAsArrayType(CurrentType); 8701 if(!AT) 8702 return ExprError(Diag(OC.LocEnd, diag::err_offsetof_array_type) 8703 << CurrentType); 8704 CurrentType = AT->getElementType(); 8705 } else 8706 CurrentType = Context.DependentTy; 8707 8708 ExprResult IdxRval = DefaultLvalueConversion(static_cast<Expr*>(OC.U.E)); 8709 if (IdxRval.isInvalid()) 8710 return ExprError(); 8711 Expr *Idx = IdxRval.take(); 8712 8713 // The expression must be an integral expression. 8714 // FIXME: An integral constant expression? 8715 if (!Idx->isTypeDependent() && !Idx->isValueDependent() && 8716 !Idx->getType()->isIntegerType()) 8717 return ExprError(Diag(Idx->getLocStart(), 8718 diag::err_typecheck_subscript_not_integer) 8719 << Idx->getSourceRange()); 8720 8721 // Record this array index. 8722 Comps.push_back(OffsetOfNode(OC.LocStart, Exprs.size(), OC.LocEnd)); 8723 Exprs.push_back(Idx); 8724 continue; 8725 } 8726 8727 // Offset of a field. 8728 if (CurrentType->isDependentType()) { 8729 // We have the offset of a field, but we can't look into the dependent 8730 // type. Just record the identifier of the field. 8731 Comps.push_back(OffsetOfNode(OC.LocStart, OC.U.IdentInfo, OC.LocEnd)); 8732 CurrentType = Context.DependentTy; 8733 continue; 8734 } 8735 8736 // We need to have a complete type to look into. 8737 if (RequireCompleteType(OC.LocStart, CurrentType, 8738 diag::err_offsetof_incomplete_type)) 8739 return ExprError(); 8740 8741 // Look for the designated field. 8742 const RecordType *RC = CurrentType->getAs<RecordType>(); 8743 if (!RC) 8744 return ExprError(Diag(OC.LocEnd, diag::err_offsetof_record_type) 8745 << CurrentType); 8746 RecordDecl *RD = RC->getDecl(); 8747 8748 // C++ [lib.support.types]p5: 8749 // The macro offsetof accepts a restricted set of type arguments in this 8750 // International Standard. type shall be a POD structure or a POD union 8751 // (clause 9). 8752 if (CXXRecordDecl *CRD = dyn_cast<CXXRecordDecl>(RD)) { 8753 if (!CRD->isPOD() && !DidWarnAboutNonPOD && 8754 DiagRuntimeBehavior(BuiltinLoc, 0, 8755 PDiag(diag::warn_offsetof_non_pod_type) 8756 << SourceRange(CompPtr[0].LocStart, OC.LocEnd) 8757 << CurrentType)) 8758 DidWarnAboutNonPOD = true; 8759 } 8760 8761 // Look for the field. 8762 LookupResult R(*this, OC.U.IdentInfo, OC.LocStart, LookupMemberName); 8763 LookupQualifiedName(R, RD); 8764 FieldDecl *MemberDecl = R.getAsSingle<FieldDecl>(); 8765 IndirectFieldDecl *IndirectMemberDecl = 0; 8766 if (!MemberDecl) { 8767 if ((IndirectMemberDecl = R.getAsSingle<IndirectFieldDecl>())) 8768 MemberDecl = IndirectMemberDecl->getAnonField(); 8769 } 8770 8771 if (!MemberDecl) 8772 return ExprError(Diag(BuiltinLoc, diag::err_no_member) 8773 << OC.U.IdentInfo << RD << SourceRange(OC.LocStart, 8774 OC.LocEnd)); 8775 8776 // C99 7.17p3: 8777 // (If the specified member is a bit-field, the behavior is undefined.) 8778 // 8779 // We diagnose this as an error. 8780 if (MemberDecl->isBitField()) { 8781 Diag(OC.LocEnd, diag::err_offsetof_bitfield) 8782 << MemberDecl->getDeclName() 8783 << SourceRange(BuiltinLoc, RParenLoc); 8784 Diag(MemberDecl->getLocation(), diag::note_bitfield_decl); 8785 return ExprError(); 8786 } 8787 8788 RecordDecl *Parent = MemberDecl->getParent(); 8789 if (IndirectMemberDecl) 8790 Parent = cast<RecordDecl>(IndirectMemberDecl->getDeclContext()); 8791 8792 // If the member was found in a base class, introduce OffsetOfNodes for 8793 // the base class indirections. 8794 CXXBasePaths Paths(/*FindAmbiguities=*/true, /*RecordPaths=*/true, 8795 /*DetectVirtual=*/false); 8796 if (IsDerivedFrom(CurrentType, Context.getTypeDeclType(Parent), Paths)) { 8797 CXXBasePath &Path = Paths.front(); 8798 for (CXXBasePath::iterator B = Path.begin(), BEnd = Path.end(); 8799 B != BEnd; ++B) 8800 Comps.push_back(OffsetOfNode(B->Base)); 8801 } 8802 8803 if (IndirectMemberDecl) { 8804 for (IndirectFieldDecl::chain_iterator FI = 8805 IndirectMemberDecl->chain_begin(), 8806 FEnd = IndirectMemberDecl->chain_end(); FI != FEnd; FI++) { 8807 assert(isa<FieldDecl>(*FI)); 8808 Comps.push_back(OffsetOfNode(OC.LocStart, 8809 cast<FieldDecl>(*FI), OC.LocEnd)); 8810 } 8811 } else 8812 Comps.push_back(OffsetOfNode(OC.LocStart, MemberDecl, OC.LocEnd)); 8813 8814 CurrentType = MemberDecl->getType().getNonReferenceType(); 8815 } 8816 8817 return Owned(OffsetOfExpr::Create(Context, Context.getSizeType(), BuiltinLoc, 8818 TInfo, Comps.data(), Comps.size(), 8819 Exprs.data(), Exprs.size(), RParenLoc)); 8820} 8821 8822ExprResult Sema::ActOnBuiltinOffsetOf(Scope *S, 8823 SourceLocation BuiltinLoc, 8824 SourceLocation TypeLoc, 8825 ParsedType ParsedArgTy, 8826 OffsetOfComponent *CompPtr, 8827 unsigned NumComponents, 8828 SourceLocation RParenLoc) { 8829 8830 TypeSourceInfo *ArgTInfo; 8831 QualType ArgTy = GetTypeFromParser(ParsedArgTy, &ArgTInfo); 8832 if (ArgTy.isNull()) 8833 return ExprError(); 8834 8835 if (!ArgTInfo) 8836 ArgTInfo = Context.getTrivialTypeSourceInfo(ArgTy, TypeLoc); 8837 8838 return BuildBuiltinOffsetOf(BuiltinLoc, ArgTInfo, CompPtr, NumComponents, 8839 RParenLoc); 8840} 8841 8842 8843ExprResult Sema::ActOnChooseExpr(SourceLocation BuiltinLoc, 8844 Expr *CondExpr, 8845 Expr *LHSExpr, Expr *RHSExpr, 8846 SourceLocation RPLoc) { 8847 assert((CondExpr && LHSExpr && RHSExpr) && "Missing type argument(s)"); 8848 8849 ExprValueKind VK = VK_RValue; 8850 ExprObjectKind OK = OK_Ordinary; 8851 QualType resType; 8852 bool ValueDependent = false; 8853 if (CondExpr->isTypeDependent() || CondExpr->isValueDependent()) { 8854 resType = Context.DependentTy; 8855 ValueDependent = true; 8856 } else { 8857 // The conditional expression is required to be a constant expression. 8858 llvm::APSInt condEval(32); 8859 ExprResult CondICE = VerifyIntegerConstantExpression(CondExpr, &condEval, 8860 PDiag(diag::err_typecheck_choose_expr_requires_constant), false); 8861 if (CondICE.isInvalid()) 8862 return ExprError(); 8863 CondExpr = CondICE.take(); 8864 8865 // If the condition is > zero, then the AST type is the same as the LSHExpr. 8866 Expr *ActiveExpr = condEval.getZExtValue() ? LHSExpr : RHSExpr; 8867 8868 resType = ActiveExpr->getType(); 8869 ValueDependent = ActiveExpr->isValueDependent(); 8870 VK = ActiveExpr->getValueKind(); 8871 OK = ActiveExpr->getObjectKind(); 8872 } 8873 8874 return Owned(new (Context) ChooseExpr(BuiltinLoc, CondExpr, LHSExpr, RHSExpr, 8875 resType, VK, OK, RPLoc, 8876 resType->isDependentType(), 8877 ValueDependent)); 8878} 8879 8880//===----------------------------------------------------------------------===// 8881// Clang Extensions. 8882//===----------------------------------------------------------------------===// 8883 8884/// ActOnBlockStart - This callback is invoked when a block literal is started. 8885void Sema::ActOnBlockStart(SourceLocation CaretLoc, Scope *CurScope) { 8886 BlockDecl *Block = BlockDecl::Create(Context, CurContext, CaretLoc); 8887 PushBlockScope(CurScope, Block); 8888 CurContext->addDecl(Block); 8889 if (CurScope) 8890 PushDeclContext(CurScope, Block); 8891 else 8892 CurContext = Block; 8893 8894 getCurBlock()->HasImplicitReturnType = true; 8895 8896 // Enter a new evaluation context to insulate the block from any 8897 // cleanups from the enclosing full-expression. 8898 PushExpressionEvaluationContext(PotentiallyEvaluated); 8899} 8900 8901void Sema::ActOnBlockArguments(Declarator &ParamInfo, Scope *CurScope) { 8902 assert(ParamInfo.getIdentifier()==0 && "block-id should have no identifier!"); 8903 assert(ParamInfo.getContext() == Declarator::BlockLiteralContext); 8904 BlockScopeInfo *CurBlock = getCurBlock(); 8905 8906 TypeSourceInfo *Sig = GetTypeForDeclarator(ParamInfo, CurScope); 8907 QualType T = Sig->getType(); 8908 8909 // GetTypeForDeclarator always produces a function type for a block 8910 // literal signature. Furthermore, it is always a FunctionProtoType 8911 // unless the function was written with a typedef. 8912 assert(T->isFunctionType() && 8913 "GetTypeForDeclarator made a non-function block signature"); 8914 8915 // Look for an explicit signature in that function type. 8916 FunctionProtoTypeLoc ExplicitSignature; 8917 8918 TypeLoc tmp = Sig->getTypeLoc().IgnoreParens(); 8919 if (isa<FunctionProtoTypeLoc>(tmp)) { 8920 ExplicitSignature = cast<FunctionProtoTypeLoc>(tmp); 8921 8922 // Check whether that explicit signature was synthesized by 8923 // GetTypeForDeclarator. If so, don't save that as part of the 8924 // written signature. 8925 if (ExplicitSignature.getLocalRangeBegin() == 8926 ExplicitSignature.getLocalRangeEnd()) { 8927 // This would be much cheaper if we stored TypeLocs instead of 8928 // TypeSourceInfos. 8929 TypeLoc Result = ExplicitSignature.getResultLoc(); 8930 unsigned Size = Result.getFullDataSize(); 8931 Sig = Context.CreateTypeSourceInfo(Result.getType(), Size); 8932 Sig->getTypeLoc().initializeFullCopy(Result, Size); 8933 8934 ExplicitSignature = FunctionProtoTypeLoc(); 8935 } 8936 } 8937 8938 CurBlock->TheDecl->setSignatureAsWritten(Sig); 8939 CurBlock->FunctionType = T; 8940 8941 const FunctionType *Fn = T->getAs<FunctionType>(); 8942 QualType RetTy = Fn->getResultType(); 8943 bool isVariadic = 8944 (isa<FunctionProtoType>(Fn) && cast<FunctionProtoType>(Fn)->isVariadic()); 8945 8946 CurBlock->TheDecl->setIsVariadic(isVariadic); 8947 8948 // Don't allow returning a objc interface by value. 8949 if (RetTy->isObjCObjectType()) { 8950 Diag(ParamInfo.getLocStart(), 8951 diag::err_object_cannot_be_passed_returned_by_value) << 0 << RetTy; 8952 return; 8953 } 8954 8955 // Context.DependentTy is used as a placeholder for a missing block 8956 // return type. TODO: what should we do with declarators like: 8957 // ^ * { ... } 8958 // If the answer is "apply template argument deduction".... 8959 if (RetTy != Context.DependentTy) { 8960 CurBlock->ReturnType = RetTy; 8961 CurBlock->TheDecl->setBlockMissingReturnType(false); 8962 CurBlock->HasImplicitReturnType = false; 8963 } 8964 8965 // Push block parameters from the declarator if we had them. 8966 SmallVector<ParmVarDecl*, 8> Params; 8967 if (ExplicitSignature) { 8968 for (unsigned I = 0, E = ExplicitSignature.getNumArgs(); I != E; ++I) { 8969 ParmVarDecl *Param = ExplicitSignature.getArg(I); 8970 if (Param->getIdentifier() == 0 && 8971 !Param->isImplicit() && 8972 !Param->isInvalidDecl() && 8973 !getLangOpts().CPlusPlus) 8974 Diag(Param->getLocation(), diag::err_parameter_name_omitted); 8975 Params.push_back(Param); 8976 } 8977 8978 // Fake up parameter variables if we have a typedef, like 8979 // ^ fntype { ... } 8980 } else if (const FunctionProtoType *Fn = T->getAs<FunctionProtoType>()) { 8981 for (FunctionProtoType::arg_type_iterator 8982 I = Fn->arg_type_begin(), E = Fn->arg_type_end(); I != E; ++I) { 8983 ParmVarDecl *Param = 8984 BuildParmVarDeclForTypedef(CurBlock->TheDecl, 8985 ParamInfo.getLocStart(), 8986 *I); 8987 Params.push_back(Param); 8988 } 8989 } 8990 8991 // Set the parameters on the block decl. 8992 if (!Params.empty()) { 8993 CurBlock->TheDecl->setParams(Params); 8994 CheckParmsForFunctionDef(CurBlock->TheDecl->param_begin(), 8995 CurBlock->TheDecl->param_end(), 8996 /*CheckParameterNames=*/false); 8997 } 8998 8999 // Finally we can process decl attributes. 9000 ProcessDeclAttributes(CurScope, CurBlock->TheDecl, ParamInfo); 9001 9002 // Put the parameter variables in scope. We can bail out immediately 9003 // if we don't have any. 9004 if (Params.empty()) 9005 return; 9006 9007 for (BlockDecl::param_iterator AI = CurBlock->TheDecl->param_begin(), 9008 E = CurBlock->TheDecl->param_end(); AI != E; ++AI) { 9009 (*AI)->setOwningFunction(CurBlock->TheDecl); 9010 9011 // If this has an identifier, add it to the scope stack. 9012 if ((*AI)->getIdentifier()) { 9013 CheckShadow(CurBlock->TheScope, *AI); 9014 9015 PushOnScopeChains(*AI, CurBlock->TheScope); 9016 } 9017 } 9018} 9019 9020/// ActOnBlockError - If there is an error parsing a block, this callback 9021/// is invoked to pop the information about the block from the action impl. 9022void Sema::ActOnBlockError(SourceLocation CaretLoc, Scope *CurScope) { 9023 // Leave the expression-evaluation context. 9024 DiscardCleanupsInEvaluationContext(); 9025 PopExpressionEvaluationContext(); 9026 9027 // Pop off CurBlock, handle nested blocks. 9028 PopDeclContext(); 9029 PopFunctionScopeInfo(); 9030} 9031 9032/// ActOnBlockStmtExpr - This is called when the body of a block statement 9033/// literal was successfully completed. ^(int x){...} 9034ExprResult Sema::ActOnBlockStmtExpr(SourceLocation CaretLoc, 9035 Stmt *Body, Scope *CurScope) { 9036 // If blocks are disabled, emit an error. 9037 if (!LangOpts.Blocks) 9038 Diag(CaretLoc, diag::err_blocks_disable); 9039 9040 // Leave the expression-evaluation context. 9041 if (hasAnyUnrecoverableErrorsInThisFunction()) 9042 DiscardCleanupsInEvaluationContext(); 9043 assert(!ExprNeedsCleanups && "cleanups within block not correctly bound!"); 9044 PopExpressionEvaluationContext(); 9045 9046 BlockScopeInfo *BSI = cast<BlockScopeInfo>(FunctionScopes.back()); 9047 9048 PopDeclContext(); 9049 9050 QualType RetTy = Context.VoidTy; 9051 if (!BSI->ReturnType.isNull()) 9052 RetTy = BSI->ReturnType; 9053 9054 bool NoReturn = BSI->TheDecl->getAttr<NoReturnAttr>(); 9055 QualType BlockTy; 9056 9057 // Set the captured variables on the block. 9058 // FIXME: Share capture structure between BlockDecl and CapturingScopeInfo! 9059 SmallVector<BlockDecl::Capture, 4> Captures; 9060 for (unsigned i = 0, e = BSI->Captures.size(); i != e; i++) { 9061 CapturingScopeInfo::Capture &Cap = BSI->Captures[i]; 9062 if (Cap.isThisCapture()) 9063 continue; 9064 BlockDecl::Capture NewCap(Cap.getVariable(), Cap.isBlockCapture(), 9065 Cap.isNested(), Cap.getCopyExpr()); 9066 Captures.push_back(NewCap); 9067 } 9068 BSI->TheDecl->setCaptures(Context, Captures.begin(), Captures.end(), 9069 BSI->CXXThisCaptureIndex != 0); 9070 9071 // If the user wrote a function type in some form, try to use that. 9072 if (!BSI->FunctionType.isNull()) { 9073 const FunctionType *FTy = BSI->FunctionType->getAs<FunctionType>(); 9074 9075 FunctionType::ExtInfo Ext = FTy->getExtInfo(); 9076 if (NoReturn && !Ext.getNoReturn()) Ext = Ext.withNoReturn(true); 9077 9078 // Turn protoless block types into nullary block types. 9079 if (isa<FunctionNoProtoType>(FTy)) { 9080 FunctionProtoType::ExtProtoInfo EPI; 9081 EPI.ExtInfo = Ext; 9082 BlockTy = Context.getFunctionType(RetTy, 0, 0, EPI); 9083 9084 // Otherwise, if we don't need to change anything about the function type, 9085 // preserve its sugar structure. 9086 } else if (FTy->getResultType() == RetTy && 9087 (!NoReturn || FTy->getNoReturnAttr())) { 9088 BlockTy = BSI->FunctionType; 9089 9090 // Otherwise, make the minimal modifications to the function type. 9091 } else { 9092 const FunctionProtoType *FPT = cast<FunctionProtoType>(FTy); 9093 FunctionProtoType::ExtProtoInfo EPI = FPT->getExtProtoInfo(); 9094 EPI.TypeQuals = 0; // FIXME: silently? 9095 EPI.ExtInfo = Ext; 9096 BlockTy = Context.getFunctionType(RetTy, 9097 FPT->arg_type_begin(), 9098 FPT->getNumArgs(), 9099 EPI); 9100 } 9101 9102 // If we don't have a function type, just build one from nothing. 9103 } else { 9104 FunctionProtoType::ExtProtoInfo EPI; 9105 EPI.ExtInfo = FunctionType::ExtInfo().withNoReturn(NoReturn); 9106 BlockTy = Context.getFunctionType(RetTy, 0, 0, EPI); 9107 } 9108 9109 DiagnoseUnusedParameters(BSI->TheDecl->param_begin(), 9110 BSI->TheDecl->param_end()); 9111 BlockTy = Context.getBlockPointerType(BlockTy); 9112 9113 // If needed, diagnose invalid gotos and switches in the block. 9114 if (getCurFunction()->NeedsScopeChecking() && 9115 !hasAnyUnrecoverableErrorsInThisFunction()) 9116 DiagnoseInvalidJumps(cast<CompoundStmt>(Body)); 9117 9118 BSI->TheDecl->setBody(cast<CompoundStmt>(Body)); 9119 9120 for (BlockDecl::capture_const_iterator ci = BSI->TheDecl->capture_begin(), 9121 ce = BSI->TheDecl->capture_end(); ci != ce; ++ci) { 9122 const VarDecl *variable = ci->getVariable(); 9123 QualType T = variable->getType(); 9124 QualType::DestructionKind destructKind = T.isDestructedType(); 9125 if (destructKind != QualType::DK_none) 9126 getCurFunction()->setHasBranchProtectedScope(); 9127 } 9128 9129 computeNRVO(Body, getCurBlock()); 9130 9131 BlockExpr *Result = new (Context) BlockExpr(BSI->TheDecl, BlockTy); 9132 const AnalysisBasedWarnings::Policy &WP = AnalysisWarnings.getDefaultPolicy(); 9133 PopFunctionScopeInfo(&WP, Result->getBlockDecl(), Result); 9134 9135 // If the block isn't obviously global, i.e. it captures anything at 9136 // all, mark this full-expression as needing a cleanup. 9137 if (Result->getBlockDecl()->hasCaptures()) { 9138 ExprCleanupObjects.push_back(Result->getBlockDecl()); 9139 ExprNeedsCleanups = true; 9140 } 9141 9142 return Owned(Result); 9143} 9144 9145ExprResult Sema::ActOnVAArg(SourceLocation BuiltinLoc, 9146 Expr *E, ParsedType Ty, 9147 SourceLocation RPLoc) { 9148 TypeSourceInfo *TInfo; 9149 GetTypeFromParser(Ty, &TInfo); 9150 return BuildVAArgExpr(BuiltinLoc, E, TInfo, RPLoc); 9151} 9152 9153ExprResult Sema::BuildVAArgExpr(SourceLocation BuiltinLoc, 9154 Expr *E, TypeSourceInfo *TInfo, 9155 SourceLocation RPLoc) { 9156 Expr *OrigExpr = E; 9157 9158 // Get the va_list type 9159 QualType VaListType = Context.getBuiltinVaListType(); 9160 if (VaListType->isArrayType()) { 9161 // Deal with implicit array decay; for example, on x86-64, 9162 // va_list is an array, but it's supposed to decay to 9163 // a pointer for va_arg. 9164 VaListType = Context.getArrayDecayedType(VaListType); 9165 // Make sure the input expression also decays appropriately. 9166 ExprResult Result = UsualUnaryConversions(E); 9167 if (Result.isInvalid()) 9168 return ExprError(); 9169 E = Result.take(); 9170 } else { 9171 // Otherwise, the va_list argument must be an l-value because 9172 // it is modified by va_arg. 9173 if (!E->isTypeDependent() && 9174 CheckForModifiableLvalue(E, BuiltinLoc, *this)) 9175 return ExprError(); 9176 } 9177 9178 if (!E->isTypeDependent() && 9179 !Context.hasSameType(VaListType, E->getType())) { 9180 return ExprError(Diag(E->getLocStart(), 9181 diag::err_first_argument_to_va_arg_not_of_type_va_list) 9182 << OrigExpr->getType() << E->getSourceRange()); 9183 } 9184 9185 if (!TInfo->getType()->isDependentType()) { 9186 if (RequireCompleteType(TInfo->getTypeLoc().getBeginLoc(), TInfo->getType(), 9187 PDiag(diag::err_second_parameter_to_va_arg_incomplete) 9188 << TInfo->getTypeLoc().getSourceRange())) 9189 return ExprError(); 9190 9191 if (RequireNonAbstractType(TInfo->getTypeLoc().getBeginLoc(), 9192 TInfo->getType(), 9193 PDiag(diag::err_second_parameter_to_va_arg_abstract) 9194 << TInfo->getTypeLoc().getSourceRange())) 9195 return ExprError(); 9196 9197 if (!TInfo->getType().isPODType(Context)) { 9198 Diag(TInfo->getTypeLoc().getBeginLoc(), 9199 TInfo->getType()->isObjCLifetimeType() 9200 ? diag::warn_second_parameter_to_va_arg_ownership_qualified 9201 : diag::warn_second_parameter_to_va_arg_not_pod) 9202 << TInfo->getType() 9203 << TInfo->getTypeLoc().getSourceRange(); 9204 } 9205 9206 // Check for va_arg where arguments of the given type will be promoted 9207 // (i.e. this va_arg is guaranteed to have undefined behavior). 9208 QualType PromoteType; 9209 if (TInfo->getType()->isPromotableIntegerType()) { 9210 PromoteType = Context.getPromotedIntegerType(TInfo->getType()); 9211 if (Context.typesAreCompatible(PromoteType, TInfo->getType())) 9212 PromoteType = QualType(); 9213 } 9214 if (TInfo->getType()->isSpecificBuiltinType(BuiltinType::Float)) 9215 PromoteType = Context.DoubleTy; 9216 if (!PromoteType.isNull()) 9217 Diag(TInfo->getTypeLoc().getBeginLoc(), 9218 diag::warn_second_parameter_to_va_arg_never_compatible) 9219 << TInfo->getType() 9220 << PromoteType 9221 << TInfo->getTypeLoc().getSourceRange(); 9222 } 9223 9224 QualType T = TInfo->getType().getNonLValueExprType(Context); 9225 return Owned(new (Context) VAArgExpr(BuiltinLoc, E, TInfo, RPLoc, T)); 9226} 9227 9228ExprResult Sema::ActOnGNUNullExpr(SourceLocation TokenLoc) { 9229 // The type of __null will be int or long, depending on the size of 9230 // pointers on the target. 9231 QualType Ty; 9232 unsigned pw = Context.getTargetInfo().getPointerWidth(0); 9233 if (pw == Context.getTargetInfo().getIntWidth()) 9234 Ty = Context.IntTy; 9235 else if (pw == Context.getTargetInfo().getLongWidth()) 9236 Ty = Context.LongTy; 9237 else if (pw == Context.getTargetInfo().getLongLongWidth()) 9238 Ty = Context.LongLongTy; 9239 else { 9240 llvm_unreachable("I don't know size of pointer!"); 9241 } 9242 9243 return Owned(new (Context) GNUNullExpr(Ty, TokenLoc)); 9244} 9245 9246static void MakeObjCStringLiteralFixItHint(Sema& SemaRef, QualType DstType, 9247 Expr *SrcExpr, FixItHint &Hint) { 9248 if (!SemaRef.getLangOpts().ObjC1) 9249 return; 9250 9251 const ObjCObjectPointerType *PT = DstType->getAs<ObjCObjectPointerType>(); 9252 if (!PT) 9253 return; 9254 9255 // Check if the destination is of type 'id'. 9256 if (!PT->isObjCIdType()) { 9257 // Check if the destination is the 'NSString' interface. 9258 const ObjCInterfaceDecl *ID = PT->getInterfaceDecl(); 9259 if (!ID || !ID->getIdentifier()->isStr("NSString")) 9260 return; 9261 } 9262 9263 // Ignore any parens, implicit casts (should only be 9264 // array-to-pointer decays), and not-so-opaque values. The last is 9265 // important for making this trigger for property assignments. 9266 SrcExpr = SrcExpr->IgnoreParenImpCasts(); 9267 if (OpaqueValueExpr *OV = dyn_cast<OpaqueValueExpr>(SrcExpr)) 9268 if (OV->getSourceExpr()) 9269 SrcExpr = OV->getSourceExpr()->IgnoreParenImpCasts(); 9270 9271 StringLiteral *SL = dyn_cast<StringLiteral>(SrcExpr); 9272 if (!SL || !SL->isAscii()) 9273 return; 9274 9275 Hint = FixItHint::CreateInsertion(SL->getLocStart(), "@"); 9276} 9277 9278bool Sema::DiagnoseAssignmentResult(AssignConvertType ConvTy, 9279 SourceLocation Loc, 9280 QualType DstType, QualType SrcType, 9281 Expr *SrcExpr, AssignmentAction Action, 9282 bool *Complained) { 9283 if (Complained) 9284 *Complained = false; 9285 9286 // Decode the result (notice that AST's are still created for extensions). 9287 bool CheckInferredResultType = false; 9288 bool isInvalid = false; 9289 unsigned DiagKind = 0; 9290 FixItHint Hint; 9291 ConversionFixItGenerator ConvHints; 9292 bool MayHaveConvFixit = false; 9293 bool MayHaveFunctionDiff = false; 9294 9295 switch (ConvTy) { 9296 case Compatible: return false; 9297 case PointerToInt: 9298 DiagKind = diag::ext_typecheck_convert_pointer_int; 9299 ConvHints.tryToFixConversion(SrcExpr, SrcType, DstType, *this); 9300 MayHaveConvFixit = true; 9301 break; 9302 case IntToPointer: 9303 DiagKind = diag::ext_typecheck_convert_int_pointer; 9304 ConvHints.tryToFixConversion(SrcExpr, SrcType, DstType, *this); 9305 MayHaveConvFixit = true; 9306 break; 9307 case IncompatiblePointer: 9308 MakeObjCStringLiteralFixItHint(*this, DstType, SrcExpr, Hint); 9309 DiagKind = diag::ext_typecheck_convert_incompatible_pointer; 9310 CheckInferredResultType = DstType->isObjCObjectPointerType() && 9311 SrcType->isObjCObjectPointerType(); 9312 if (Hint.isNull() && !CheckInferredResultType) { 9313 ConvHints.tryToFixConversion(SrcExpr, SrcType, DstType, *this); 9314 } 9315 MayHaveConvFixit = true; 9316 break; 9317 case IncompatiblePointerSign: 9318 DiagKind = diag::ext_typecheck_convert_incompatible_pointer_sign; 9319 break; 9320 case FunctionVoidPointer: 9321 DiagKind = diag::ext_typecheck_convert_pointer_void_func; 9322 break; 9323 case IncompatiblePointerDiscardsQualifiers: { 9324 // Perform array-to-pointer decay if necessary. 9325 if (SrcType->isArrayType()) SrcType = Context.getArrayDecayedType(SrcType); 9326 9327 Qualifiers lhq = SrcType->getPointeeType().getQualifiers(); 9328 Qualifiers rhq = DstType->getPointeeType().getQualifiers(); 9329 if (lhq.getAddressSpace() != rhq.getAddressSpace()) { 9330 DiagKind = diag::err_typecheck_incompatible_address_space; 9331 break; 9332 9333 9334 } else if (lhq.getObjCLifetime() != rhq.getObjCLifetime()) { 9335 DiagKind = diag::err_typecheck_incompatible_ownership; 9336 break; 9337 } 9338 9339 llvm_unreachable("unknown error case for discarding qualifiers!"); 9340 // fallthrough 9341 } 9342 case CompatiblePointerDiscardsQualifiers: 9343 // If the qualifiers lost were because we were applying the 9344 // (deprecated) C++ conversion from a string literal to a char* 9345 // (or wchar_t*), then there was no error (C++ 4.2p2). FIXME: 9346 // Ideally, this check would be performed in 9347 // checkPointerTypesForAssignment. However, that would require a 9348 // bit of refactoring (so that the second argument is an 9349 // expression, rather than a type), which should be done as part 9350 // of a larger effort to fix checkPointerTypesForAssignment for 9351 // C++ semantics. 9352 if (getLangOpts().CPlusPlus && 9353 IsStringLiteralToNonConstPointerConversion(SrcExpr, DstType)) 9354 return false; 9355 DiagKind = diag::ext_typecheck_convert_discards_qualifiers; 9356 break; 9357 case IncompatibleNestedPointerQualifiers: 9358 DiagKind = diag::ext_nested_pointer_qualifier_mismatch; 9359 break; 9360 case IntToBlockPointer: 9361 DiagKind = diag::err_int_to_block_pointer; 9362 break; 9363 case IncompatibleBlockPointer: 9364 DiagKind = diag::err_typecheck_convert_incompatible_block_pointer; 9365 break; 9366 case IncompatibleObjCQualifiedId: 9367 // FIXME: Diagnose the problem in ObjCQualifiedIdTypesAreCompatible, since 9368 // it can give a more specific diagnostic. 9369 DiagKind = diag::warn_incompatible_qualified_id; 9370 break; 9371 case IncompatibleVectors: 9372 DiagKind = diag::warn_incompatible_vectors; 9373 break; 9374 case IncompatibleObjCWeakRef: 9375 DiagKind = diag::err_arc_weak_unavailable_assign; 9376 break; 9377 case Incompatible: 9378 DiagKind = diag::err_typecheck_convert_incompatible; 9379 ConvHints.tryToFixConversion(SrcExpr, SrcType, DstType, *this); 9380 MayHaveConvFixit = true; 9381 isInvalid = true; 9382 MayHaveFunctionDiff = true; 9383 break; 9384 } 9385 9386 QualType FirstType, SecondType; 9387 switch (Action) { 9388 case AA_Assigning: 9389 case AA_Initializing: 9390 // The destination type comes first. 9391 FirstType = DstType; 9392 SecondType = SrcType; 9393 break; 9394 9395 case AA_Returning: 9396 case AA_Passing: 9397 case AA_Converting: 9398 case AA_Sending: 9399 case AA_Casting: 9400 // The source type comes first. 9401 FirstType = SrcType; 9402 SecondType = DstType; 9403 break; 9404 } 9405 9406 PartialDiagnostic FDiag = PDiag(DiagKind); 9407 FDiag << FirstType << SecondType << Action << SrcExpr->getSourceRange(); 9408 9409 // If we can fix the conversion, suggest the FixIts. 9410 assert(ConvHints.isNull() || Hint.isNull()); 9411 if (!ConvHints.isNull()) { 9412 for (std::vector<FixItHint>::iterator HI = ConvHints.Hints.begin(), 9413 HE = ConvHints.Hints.end(); HI != HE; ++HI) 9414 FDiag << *HI; 9415 } else { 9416 FDiag << Hint; 9417 } 9418 if (MayHaveConvFixit) { FDiag << (unsigned) (ConvHints.Kind); } 9419 9420 if (MayHaveFunctionDiff) 9421 HandleFunctionTypeMismatch(FDiag, SecondType, FirstType); 9422 9423 Diag(Loc, FDiag); 9424 9425 if (SecondType == Context.OverloadTy) 9426 NoteAllOverloadCandidates(OverloadExpr::find(SrcExpr).Expression, 9427 FirstType); 9428 9429 if (CheckInferredResultType) 9430 EmitRelatedResultTypeNote(SrcExpr); 9431 9432 if (Complained) 9433 *Complained = true; 9434 return isInvalid; 9435} 9436 9437ExprResult Sema::VerifyIntegerConstantExpression(Expr *E, 9438 llvm::APSInt *Result) { 9439 return VerifyIntegerConstantExpression(E, Result, 9440 PDiag(diag::err_expr_not_ice) << LangOpts.CPlusPlus); 9441} 9442 9443ExprResult Sema::VerifyIntegerConstantExpression(Expr *E, llvm::APSInt *Result, 9444 PartialDiagnostic NotIceDiag, 9445 bool AllowFold, 9446 PartialDiagnostic FoldDiag) { 9447 SourceLocation DiagLoc = E->getLocStart(); 9448 9449 if (getLangOpts().CPlusPlus0x) { 9450 // C++11 [expr.const]p5: 9451 // If an expression of literal class type is used in a context where an 9452 // integral constant expression is required, then that class type shall 9453 // have a single non-explicit conversion function to an integral or 9454 // unscoped enumeration type 9455 ExprResult Converted; 9456 if (NotIceDiag.getDiagID()) { 9457 Converted = ConvertToIntegralOrEnumerationType( 9458 DiagLoc, E, 9459 PDiag(diag::err_ice_not_integral), 9460 PDiag(diag::err_ice_incomplete_type), 9461 PDiag(diag::err_ice_explicit_conversion), 9462 PDiag(diag::note_ice_conversion_here), 9463 PDiag(diag::err_ice_ambiguous_conversion), 9464 PDiag(diag::note_ice_conversion_here), 9465 PDiag(0), 9466 /*AllowScopedEnumerations*/ false); 9467 } else { 9468 // The caller wants to silently enquire whether this is an ICE. Don't 9469 // produce any diagnostics if it isn't. 9470 Converted = ConvertToIntegralOrEnumerationType( 9471 DiagLoc, E, PDiag(), PDiag(), PDiag(), PDiag(), 9472 PDiag(), PDiag(), PDiag(), false); 9473 } 9474 if (Converted.isInvalid()) 9475 return Converted; 9476 E = Converted.take(); 9477 if (!E->getType()->isIntegralOrUnscopedEnumerationType()) 9478 return ExprError(); 9479 } else if (!E->getType()->isIntegralOrUnscopedEnumerationType()) { 9480 // An ICE must be of integral or unscoped enumeration type. 9481 if (NotIceDiag.getDiagID()) 9482 Diag(DiagLoc, NotIceDiag) << E->getSourceRange(); 9483 return ExprError(); 9484 } 9485 9486 // Circumvent ICE checking in C++11 to avoid evaluating the expression twice 9487 // in the non-ICE case. 9488 if (!getLangOpts().CPlusPlus0x && E->isIntegerConstantExpr(Context)) { 9489 if (Result) 9490 *Result = E->EvaluateKnownConstInt(Context); 9491 return Owned(E); 9492 } 9493 9494 Expr::EvalResult EvalResult; 9495 llvm::SmallVector<PartialDiagnosticAt, 8> Notes; 9496 EvalResult.Diag = &Notes; 9497 9498 // Try to evaluate the expression, and produce diagnostics explaining why it's 9499 // not a constant expression as a side-effect. 9500 bool Folded = E->EvaluateAsRValue(EvalResult, Context) && 9501 EvalResult.Val.isInt() && !EvalResult.HasSideEffects; 9502 9503 // In C++11, we can rely on diagnostics being produced for any expression 9504 // which is not a constant expression. If no diagnostics were produced, then 9505 // this is a constant expression. 9506 if (Folded && getLangOpts().CPlusPlus0x && Notes.empty()) { 9507 if (Result) 9508 *Result = EvalResult.Val.getInt(); 9509 return Owned(E); 9510 } 9511 9512 // If our only note is the usual "invalid subexpression" note, just point 9513 // the caret at its location rather than producing an essentially 9514 // redundant note. 9515 if (Notes.size() == 1 && Notes[0].second.getDiagID() == 9516 diag::note_invalid_subexpr_in_const_expr) { 9517 DiagLoc = Notes[0].first; 9518 Notes.clear(); 9519 } 9520 9521 if (!Folded || !AllowFold) { 9522 if (NotIceDiag.getDiagID()) { 9523 Diag(DiagLoc, NotIceDiag) << E->getSourceRange(); 9524 for (unsigned I = 0, N = Notes.size(); I != N; ++I) 9525 Diag(Notes[I].first, Notes[I].second); 9526 } 9527 9528 return ExprError(); 9529 } 9530 9531 if (FoldDiag.getDiagID()) 9532 Diag(DiagLoc, FoldDiag) << E->getSourceRange(); 9533 else 9534 Diag(DiagLoc, diag::ext_expr_not_ice) 9535 << E->getSourceRange() << LangOpts.CPlusPlus; 9536 for (unsigned I = 0, N = Notes.size(); I != N; ++I) 9537 Diag(Notes[I].first, Notes[I].second); 9538 9539 if (Result) 9540 *Result = EvalResult.Val.getInt(); 9541 return Owned(E); 9542} 9543 9544namespace { 9545 // Handle the case where we conclude a expression which we speculatively 9546 // considered to be unevaluated is actually evaluated. 9547 class TransformToPE : public TreeTransform<TransformToPE> { 9548 typedef TreeTransform<TransformToPE> BaseTransform; 9549 9550 public: 9551 TransformToPE(Sema &SemaRef) : BaseTransform(SemaRef) { } 9552 9553 // Make sure we redo semantic analysis 9554 bool AlwaysRebuild() { return true; } 9555 9556 // Make sure we handle LabelStmts correctly. 9557 // FIXME: This does the right thing, but maybe we need a more general 9558 // fix to TreeTransform? 9559 StmtResult TransformLabelStmt(LabelStmt *S) { 9560 S->getDecl()->setStmt(0); 9561 return BaseTransform::TransformLabelStmt(S); 9562 } 9563 9564 // We need to special-case DeclRefExprs referring to FieldDecls which 9565 // are not part of a member pointer formation; normal TreeTransforming 9566 // doesn't catch this case because of the way we represent them in the AST. 9567 // FIXME: This is a bit ugly; is it really the best way to handle this 9568 // case? 9569 // 9570 // Error on DeclRefExprs referring to FieldDecls. 9571 ExprResult TransformDeclRefExpr(DeclRefExpr *E) { 9572 if (isa<FieldDecl>(E->getDecl()) && 9573 SemaRef.ExprEvalContexts.back().Context != Sema::Unevaluated) 9574 return SemaRef.Diag(E->getLocation(), 9575 diag::err_invalid_non_static_member_use) 9576 << E->getDecl() << E->getSourceRange(); 9577 9578 return BaseTransform::TransformDeclRefExpr(E); 9579 } 9580 9581 // Exception: filter out member pointer formation 9582 ExprResult TransformUnaryOperator(UnaryOperator *E) { 9583 if (E->getOpcode() == UO_AddrOf && E->getType()->isMemberPointerType()) 9584 return E; 9585 9586 return BaseTransform::TransformUnaryOperator(E); 9587 } 9588 9589 ExprResult TransformLambdaExpr(LambdaExpr *E) { 9590 // Lambdas never need to be transformed. 9591 return E; 9592 } 9593 }; 9594} 9595 9596ExprResult Sema::TranformToPotentiallyEvaluated(Expr *E) { 9597 assert(ExprEvalContexts.back().Context == Unevaluated && 9598 "Should only transform unevaluated expressions"); 9599 ExprEvalContexts.back().Context = 9600 ExprEvalContexts[ExprEvalContexts.size()-2].Context; 9601 if (ExprEvalContexts.back().Context == Unevaluated) 9602 return E; 9603 return TransformToPE(*this).TransformExpr(E); 9604} 9605 9606void 9607Sema::PushExpressionEvaluationContext(ExpressionEvaluationContext NewContext, 9608 Decl *LambdaContextDecl, 9609 bool IsDecltype) { 9610 ExprEvalContexts.push_back( 9611 ExpressionEvaluationContextRecord(NewContext, 9612 ExprCleanupObjects.size(), 9613 ExprNeedsCleanups, 9614 LambdaContextDecl, 9615 IsDecltype)); 9616 ExprNeedsCleanups = false; 9617 if (!MaybeODRUseExprs.empty()) 9618 std::swap(MaybeODRUseExprs, ExprEvalContexts.back().SavedMaybeODRUseExprs); 9619} 9620 9621void Sema::PopExpressionEvaluationContext() { 9622 ExpressionEvaluationContextRecord& Rec = ExprEvalContexts.back(); 9623 9624 if (!Rec.Lambdas.empty()) { 9625 if (Rec.Context == Unevaluated) { 9626 // C++11 [expr.prim.lambda]p2: 9627 // A lambda-expression shall not appear in an unevaluated operand 9628 // (Clause 5). 9629 for (unsigned I = 0, N = Rec.Lambdas.size(); I != N; ++I) 9630 Diag(Rec.Lambdas[I]->getLocStart(), 9631 diag::err_lambda_unevaluated_operand); 9632 } else { 9633 // Mark the capture expressions odr-used. This was deferred 9634 // during lambda expression creation. 9635 for (unsigned I = 0, N = Rec.Lambdas.size(); I != N; ++I) { 9636 LambdaExpr *Lambda = Rec.Lambdas[I]; 9637 for (LambdaExpr::capture_init_iterator 9638 C = Lambda->capture_init_begin(), 9639 CEnd = Lambda->capture_init_end(); 9640 C != CEnd; ++C) { 9641 MarkDeclarationsReferencedInExpr(*C); 9642 } 9643 } 9644 } 9645 } 9646 9647 // When are coming out of an unevaluated context, clear out any 9648 // temporaries that we may have created as part of the evaluation of 9649 // the expression in that context: they aren't relevant because they 9650 // will never be constructed. 9651 if (Rec.Context == Unevaluated || Rec.Context == ConstantEvaluated) { 9652 ExprCleanupObjects.erase(ExprCleanupObjects.begin() + Rec.NumCleanupObjects, 9653 ExprCleanupObjects.end()); 9654 ExprNeedsCleanups = Rec.ParentNeedsCleanups; 9655 CleanupVarDeclMarking(); 9656 std::swap(MaybeODRUseExprs, Rec.SavedMaybeODRUseExprs); 9657 // Otherwise, merge the contexts together. 9658 } else { 9659 ExprNeedsCleanups |= Rec.ParentNeedsCleanups; 9660 MaybeODRUseExprs.insert(Rec.SavedMaybeODRUseExprs.begin(), 9661 Rec.SavedMaybeODRUseExprs.end()); 9662 } 9663 9664 // Pop the current expression evaluation context off the stack. 9665 ExprEvalContexts.pop_back(); 9666} 9667 9668void Sema::DiscardCleanupsInEvaluationContext() { 9669 ExprCleanupObjects.erase( 9670 ExprCleanupObjects.begin() + ExprEvalContexts.back().NumCleanupObjects, 9671 ExprCleanupObjects.end()); 9672 ExprNeedsCleanups = false; 9673 MaybeODRUseExprs.clear(); 9674} 9675 9676ExprResult Sema::HandleExprEvaluationContextForTypeof(Expr *E) { 9677 if (!E->getType()->isVariablyModifiedType()) 9678 return E; 9679 return TranformToPotentiallyEvaluated(E); 9680} 9681 9682static bool IsPotentiallyEvaluatedContext(Sema &SemaRef) { 9683 // Do not mark anything as "used" within a dependent context; wait for 9684 // an instantiation. 9685 if (SemaRef.CurContext->isDependentContext()) 9686 return false; 9687 9688 switch (SemaRef.ExprEvalContexts.back().Context) { 9689 case Sema::Unevaluated: 9690 // We are in an expression that is not potentially evaluated; do nothing. 9691 // (Depending on how you read the standard, we actually do need to do 9692 // something here for null pointer constants, but the standard's 9693 // definition of a null pointer constant is completely crazy.) 9694 return false; 9695 9696 case Sema::ConstantEvaluated: 9697 case Sema::PotentiallyEvaluated: 9698 // We are in a potentially evaluated expression (or a constant-expression 9699 // in C++03); we need to do implicit template instantiation, implicitly 9700 // define class members, and mark most declarations as used. 9701 return true; 9702 9703 case Sema::PotentiallyEvaluatedIfUsed: 9704 // Referenced declarations will only be used if the construct in the 9705 // containing expression is used. 9706 return false; 9707 } 9708 llvm_unreachable("Invalid context"); 9709} 9710 9711/// \brief Mark a function referenced, and check whether it is odr-used 9712/// (C++ [basic.def.odr]p2, C99 6.9p3) 9713void Sema::MarkFunctionReferenced(SourceLocation Loc, FunctionDecl *Func) { 9714 assert(Func && "No function?"); 9715 9716 Func->setReferenced(); 9717 9718 // Don't mark this function as used multiple times, unless it's a constexpr 9719 // function which we need to instantiate. 9720 if (Func->isUsed(false) && 9721 !(Func->isConstexpr() && !Func->getBody() && 9722 Func->isImplicitlyInstantiable())) 9723 return; 9724 9725 if (!IsPotentiallyEvaluatedContext(*this)) 9726 return; 9727 9728 // Note that this declaration has been used. 9729 if (CXXConstructorDecl *Constructor = dyn_cast<CXXConstructorDecl>(Func)) { 9730 if (Constructor->isDefaulted() && !Constructor->isDeleted()) { 9731 if (Constructor->isDefaultConstructor()) { 9732 if (Constructor->isTrivial()) 9733 return; 9734 if (!Constructor->isUsed(false)) 9735 DefineImplicitDefaultConstructor(Loc, Constructor); 9736 } else if (Constructor->isCopyConstructor()) { 9737 if (!Constructor->isUsed(false)) 9738 DefineImplicitCopyConstructor(Loc, Constructor); 9739 } else if (Constructor->isMoveConstructor()) { 9740 if (!Constructor->isUsed(false)) 9741 DefineImplicitMoveConstructor(Loc, Constructor); 9742 } 9743 } 9744 9745 MarkVTableUsed(Loc, Constructor->getParent()); 9746 } else if (CXXDestructorDecl *Destructor = 9747 dyn_cast<CXXDestructorDecl>(Func)) { 9748 if (Destructor->isDefaulted() && !Destructor->isDeleted() && 9749 !Destructor->isUsed(false)) 9750 DefineImplicitDestructor(Loc, Destructor); 9751 if (Destructor->isVirtual()) 9752 MarkVTableUsed(Loc, Destructor->getParent()); 9753 } else if (CXXMethodDecl *MethodDecl = dyn_cast<CXXMethodDecl>(Func)) { 9754 if (MethodDecl->isDefaulted() && !MethodDecl->isDeleted() && 9755 MethodDecl->isOverloadedOperator() && 9756 MethodDecl->getOverloadedOperator() == OO_Equal) { 9757 if (!MethodDecl->isUsed(false)) { 9758 if (MethodDecl->isCopyAssignmentOperator()) 9759 DefineImplicitCopyAssignment(Loc, MethodDecl); 9760 else 9761 DefineImplicitMoveAssignment(Loc, MethodDecl); 9762 } 9763 } else if (isa<CXXConversionDecl>(MethodDecl) && 9764 MethodDecl->getParent()->isLambda()) { 9765 CXXConversionDecl *Conversion = cast<CXXConversionDecl>(MethodDecl); 9766 if (Conversion->isLambdaToBlockPointerConversion()) 9767 DefineImplicitLambdaToBlockPointerConversion(Loc, Conversion); 9768 else 9769 DefineImplicitLambdaToFunctionPointerConversion(Loc, Conversion); 9770 } else if (MethodDecl->isVirtual()) 9771 MarkVTableUsed(Loc, MethodDecl->getParent()); 9772 } 9773 9774 // Recursive functions should be marked when used from another function. 9775 // FIXME: Is this really right? 9776 if (CurContext == Func) return; 9777 9778 // Implicit instantiation of function templates and member functions of 9779 // class templates. 9780 if (Func->isImplicitlyInstantiable()) { 9781 bool AlreadyInstantiated = false; 9782 SourceLocation PointOfInstantiation = Loc; 9783 if (FunctionTemplateSpecializationInfo *SpecInfo 9784 = Func->getTemplateSpecializationInfo()) { 9785 if (SpecInfo->getPointOfInstantiation().isInvalid()) 9786 SpecInfo->setPointOfInstantiation(Loc); 9787 else if (SpecInfo->getTemplateSpecializationKind() 9788 == TSK_ImplicitInstantiation) { 9789 AlreadyInstantiated = true; 9790 PointOfInstantiation = SpecInfo->getPointOfInstantiation(); 9791 } 9792 } else if (MemberSpecializationInfo *MSInfo 9793 = Func->getMemberSpecializationInfo()) { 9794 if (MSInfo->getPointOfInstantiation().isInvalid()) 9795 MSInfo->setPointOfInstantiation(Loc); 9796 else if (MSInfo->getTemplateSpecializationKind() 9797 == TSK_ImplicitInstantiation) { 9798 AlreadyInstantiated = true; 9799 PointOfInstantiation = MSInfo->getPointOfInstantiation(); 9800 } 9801 } 9802 9803 if (!AlreadyInstantiated || Func->isConstexpr()) { 9804 if (isa<CXXRecordDecl>(Func->getDeclContext()) && 9805 cast<CXXRecordDecl>(Func->getDeclContext())->isLocalClass()) 9806 PendingLocalImplicitInstantiations.push_back( 9807 std::make_pair(Func, PointOfInstantiation)); 9808 else if (Func->isConstexpr()) 9809 // Do not defer instantiations of constexpr functions, to avoid the 9810 // expression evaluator needing to call back into Sema if it sees a 9811 // call to such a function. 9812 InstantiateFunctionDefinition(PointOfInstantiation, Func); 9813 else { 9814 PendingInstantiations.push_back(std::make_pair(Func, 9815 PointOfInstantiation)); 9816 // Notify the consumer that a function was implicitly instantiated. 9817 Consumer.HandleCXXImplicitFunctionInstantiation(Func); 9818 } 9819 } 9820 } else { 9821 // Walk redefinitions, as some of them may be instantiable. 9822 for (FunctionDecl::redecl_iterator i(Func->redecls_begin()), 9823 e(Func->redecls_end()); i != e; ++i) { 9824 if (!i->isUsed(false) && i->isImplicitlyInstantiable()) 9825 MarkFunctionReferenced(Loc, *i); 9826 } 9827 } 9828 9829 // Keep track of used but undefined functions. 9830 if (!Func->isPure() && !Func->hasBody() && 9831 Func->getLinkage() != ExternalLinkage) { 9832 SourceLocation &old = UndefinedInternals[Func->getCanonicalDecl()]; 9833 if (old.isInvalid()) old = Loc; 9834 } 9835 9836 Func->setUsed(true); 9837} 9838 9839static void 9840diagnoseUncapturableValueReference(Sema &S, SourceLocation loc, 9841 VarDecl *var, DeclContext *DC) { 9842 DeclContext *VarDC = var->getDeclContext(); 9843 9844 // If the parameter still belongs to the translation unit, then 9845 // we're actually just using one parameter in the declaration of 9846 // the next. 9847 if (isa<ParmVarDecl>(var) && 9848 isa<TranslationUnitDecl>(VarDC)) 9849 return; 9850 9851 // For C code, don't diagnose about capture if we're not actually in code 9852 // right now; it's impossible to write a non-constant expression outside of 9853 // function context, so we'll get other (more useful) diagnostics later. 9854 // 9855 // For C++, things get a bit more nasty... it would be nice to suppress this 9856 // diagnostic for certain cases like using a local variable in an array bound 9857 // for a member of a local class, but the correct predicate is not obvious. 9858 if (!S.getLangOpts().CPlusPlus && !S.CurContext->isFunctionOrMethod()) 9859 return; 9860 9861 if (isa<CXXMethodDecl>(VarDC) && 9862 cast<CXXRecordDecl>(VarDC->getParent())->isLambda()) { 9863 S.Diag(loc, diag::err_reference_to_local_var_in_enclosing_lambda) 9864 << var->getIdentifier(); 9865 } else if (FunctionDecl *fn = dyn_cast<FunctionDecl>(VarDC)) { 9866 S.Diag(loc, diag::err_reference_to_local_var_in_enclosing_function) 9867 << var->getIdentifier() << fn->getDeclName(); 9868 } else if (isa<BlockDecl>(VarDC)) { 9869 S.Diag(loc, diag::err_reference_to_local_var_in_enclosing_block) 9870 << var->getIdentifier(); 9871 } else { 9872 // FIXME: Is there any other context where a local variable can be 9873 // declared? 9874 S.Diag(loc, diag::err_reference_to_local_var_in_enclosing_context) 9875 << var->getIdentifier(); 9876 } 9877 9878 S.Diag(var->getLocation(), diag::note_local_variable_declared_here) 9879 << var->getIdentifier(); 9880 9881 // FIXME: Add additional diagnostic info about class etc. which prevents 9882 // capture. 9883} 9884 9885/// \brief Capture the given variable in the given lambda expression. 9886static ExprResult captureInLambda(Sema &S, LambdaScopeInfo *LSI, 9887 VarDecl *Var, QualType FieldType, 9888 QualType DeclRefType, 9889 SourceLocation Loc) { 9890 CXXRecordDecl *Lambda = LSI->Lambda; 9891 9892 // Build the non-static data member. 9893 FieldDecl *Field 9894 = FieldDecl::Create(S.Context, Lambda, Loc, Loc, 0, FieldType, 9895 S.Context.getTrivialTypeSourceInfo(FieldType, Loc), 9896 0, false, false); 9897 Field->setImplicit(true); 9898 Field->setAccess(AS_private); 9899 Lambda->addDecl(Field); 9900 9901 // C++11 [expr.prim.lambda]p21: 9902 // When the lambda-expression is evaluated, the entities that 9903 // are captured by copy are used to direct-initialize each 9904 // corresponding non-static data member of the resulting closure 9905 // object. (For array members, the array elements are 9906 // direct-initialized in increasing subscript order.) These 9907 // initializations are performed in the (unspecified) order in 9908 // which the non-static data members are declared. 9909 9910 // Introduce a new evaluation context for the initialization, so 9911 // that temporaries introduced as part of the capture are retained 9912 // to be re-"exported" from the lambda expression itself. 9913 S.PushExpressionEvaluationContext(Sema::PotentiallyEvaluated); 9914 9915 // C++ [expr.prim.labda]p12: 9916 // An entity captured by a lambda-expression is odr-used (3.2) in 9917 // the scope containing the lambda-expression. 9918 Expr *Ref = new (S.Context) DeclRefExpr(Var, false, DeclRefType, 9919 VK_LValue, Loc); 9920 Var->setReferenced(true); 9921 Var->setUsed(true); 9922 9923 // When the field has array type, create index variables for each 9924 // dimension of the array. We use these index variables to subscript 9925 // the source array, and other clients (e.g., CodeGen) will perform 9926 // the necessary iteration with these index variables. 9927 SmallVector<VarDecl *, 4> IndexVariables; 9928 QualType BaseType = FieldType; 9929 QualType SizeType = S.Context.getSizeType(); 9930 LSI->ArrayIndexStarts.push_back(LSI->ArrayIndexVars.size()); 9931 while (const ConstantArrayType *Array 9932 = S.Context.getAsConstantArrayType(BaseType)) { 9933 // Create the iteration variable for this array index. 9934 IdentifierInfo *IterationVarName = 0; 9935 { 9936 SmallString<8> Str; 9937 llvm::raw_svector_ostream OS(Str); 9938 OS << "__i" << IndexVariables.size(); 9939 IterationVarName = &S.Context.Idents.get(OS.str()); 9940 } 9941 VarDecl *IterationVar 9942 = VarDecl::Create(S.Context, S.CurContext, Loc, Loc, 9943 IterationVarName, SizeType, 9944 S.Context.getTrivialTypeSourceInfo(SizeType, Loc), 9945 SC_None, SC_None); 9946 IndexVariables.push_back(IterationVar); 9947 LSI->ArrayIndexVars.push_back(IterationVar); 9948 9949 // Create a reference to the iteration variable. 9950 ExprResult IterationVarRef 9951 = S.BuildDeclRefExpr(IterationVar, SizeType, VK_LValue, Loc); 9952 assert(!IterationVarRef.isInvalid() && 9953 "Reference to invented variable cannot fail!"); 9954 IterationVarRef = S.DefaultLvalueConversion(IterationVarRef.take()); 9955 assert(!IterationVarRef.isInvalid() && 9956 "Conversion of invented variable cannot fail!"); 9957 9958 // Subscript the array with this iteration variable. 9959 ExprResult Subscript = S.CreateBuiltinArraySubscriptExpr( 9960 Ref, Loc, IterationVarRef.take(), Loc); 9961 if (Subscript.isInvalid()) { 9962 S.CleanupVarDeclMarking(); 9963 S.DiscardCleanupsInEvaluationContext(); 9964 S.PopExpressionEvaluationContext(); 9965 return ExprError(); 9966 } 9967 9968 Ref = Subscript.take(); 9969 BaseType = Array->getElementType(); 9970 } 9971 9972 // Construct the entity that we will be initializing. For an array, this 9973 // will be first element in the array, which may require several levels 9974 // of array-subscript entities. 9975 SmallVector<InitializedEntity, 4> Entities; 9976 Entities.reserve(1 + IndexVariables.size()); 9977 Entities.push_back( 9978 InitializedEntity::InitializeLambdaCapture(Var, Field, Loc)); 9979 for (unsigned I = 0, N = IndexVariables.size(); I != N; ++I) 9980 Entities.push_back(InitializedEntity::InitializeElement(S.Context, 9981 0, 9982 Entities.back())); 9983 9984 InitializationKind InitKind 9985 = InitializationKind::CreateDirect(Loc, Loc, Loc); 9986 InitializationSequence Init(S, Entities.back(), InitKind, &Ref, 1); 9987 ExprResult Result(true); 9988 if (!Init.Diagnose(S, Entities.back(), InitKind, &Ref, 1)) 9989 Result = Init.Perform(S, Entities.back(), InitKind, 9990 MultiExprArg(S, &Ref, 1)); 9991 9992 // If this initialization requires any cleanups (e.g., due to a 9993 // default argument to a copy constructor), note that for the 9994 // lambda. 9995 if (S.ExprNeedsCleanups) 9996 LSI->ExprNeedsCleanups = true; 9997 9998 // Exit the expression evaluation context used for the capture. 9999 S.CleanupVarDeclMarking(); 10000 S.DiscardCleanupsInEvaluationContext(); 10001 S.PopExpressionEvaluationContext(); 10002 return Result; 10003} 10004 10005bool Sema::tryCaptureVariable(VarDecl *Var, SourceLocation Loc, 10006 TryCaptureKind Kind, SourceLocation EllipsisLoc, 10007 bool BuildAndDiagnose, 10008 QualType &CaptureType, 10009 QualType &DeclRefType) { 10010 bool Nested = false; 10011 10012 DeclContext *DC = CurContext; 10013 if (Var->getDeclContext() == DC) return true; 10014 if (!Var->hasLocalStorage()) return true; 10015 10016 bool HasBlocksAttr = Var->hasAttr<BlocksAttr>(); 10017 10018 // Walk up the stack to determine whether we can capture the variable, 10019 // performing the "simple" checks that don't depend on type. We stop when 10020 // we've either hit the declared scope of the variable or find an existing 10021 // capture of that variable. 10022 CaptureType = Var->getType(); 10023 DeclRefType = CaptureType.getNonReferenceType(); 10024 bool Explicit = (Kind != TryCapture_Implicit); 10025 unsigned FunctionScopesIndex = FunctionScopes.size() - 1; 10026 do { 10027 // Only block literals and lambda expressions can capture; other 10028 // scopes don't work. 10029 DeclContext *ParentDC; 10030 if (isa<BlockDecl>(DC)) 10031 ParentDC = DC->getParent(); 10032 else if (isa<CXXMethodDecl>(DC) && 10033 cast<CXXMethodDecl>(DC)->getOverloadedOperator() == OO_Call && 10034 cast<CXXRecordDecl>(DC->getParent())->isLambda()) 10035 ParentDC = DC->getParent()->getParent(); 10036 else { 10037 if (BuildAndDiagnose) 10038 diagnoseUncapturableValueReference(*this, Loc, Var, DC); 10039 return true; 10040 } 10041 10042 CapturingScopeInfo *CSI = 10043 cast<CapturingScopeInfo>(FunctionScopes[FunctionScopesIndex]); 10044 10045 // Check whether we've already captured it. 10046 if (CSI->CaptureMap.count(Var)) { 10047 // If we found a capture, any subcaptures are nested. 10048 Nested = true; 10049 10050 // Retrieve the capture type for this variable. 10051 CaptureType = CSI->getCapture(Var).getCaptureType(); 10052 10053 // Compute the type of an expression that refers to this variable. 10054 DeclRefType = CaptureType.getNonReferenceType(); 10055 10056 const CapturingScopeInfo::Capture &Cap = CSI->getCapture(Var); 10057 if (Cap.isCopyCapture() && 10058 !(isa<LambdaScopeInfo>(CSI) && cast<LambdaScopeInfo>(CSI)->Mutable)) 10059 DeclRefType.addConst(); 10060 break; 10061 } 10062 10063 bool IsBlock = isa<BlockScopeInfo>(CSI); 10064 bool IsLambda = !IsBlock; 10065 10066 // Lambdas are not allowed to capture unnamed variables 10067 // (e.g. anonymous unions). 10068 // FIXME: The C++11 rule don't actually state this explicitly, but I'm 10069 // assuming that's the intent. 10070 if (IsLambda && !Var->getDeclName()) { 10071 if (BuildAndDiagnose) { 10072 Diag(Loc, diag::err_lambda_capture_anonymous_var); 10073 Diag(Var->getLocation(), diag::note_declared_at); 10074 } 10075 return true; 10076 } 10077 10078 // Prohibit variably-modified types; they're difficult to deal with. 10079 if (Var->getType()->isVariablyModifiedType()) { 10080 if (BuildAndDiagnose) { 10081 if (IsBlock) 10082 Diag(Loc, diag::err_ref_vm_type); 10083 else 10084 Diag(Loc, diag::err_lambda_capture_vm_type) << Var->getDeclName(); 10085 Diag(Var->getLocation(), diag::note_previous_decl) 10086 << Var->getDeclName(); 10087 } 10088 return true; 10089 } 10090 10091 // Lambdas are not allowed to capture __block variables; they don't 10092 // support the expected semantics. 10093 if (IsLambda && HasBlocksAttr) { 10094 if (BuildAndDiagnose) { 10095 Diag(Loc, diag::err_lambda_capture_block) 10096 << Var->getDeclName(); 10097 Diag(Var->getLocation(), diag::note_previous_decl) 10098 << Var->getDeclName(); 10099 } 10100 return true; 10101 } 10102 10103 if (CSI->ImpCaptureStyle == CapturingScopeInfo::ImpCap_None && !Explicit) { 10104 // No capture-default 10105 if (BuildAndDiagnose) { 10106 Diag(Loc, diag::err_lambda_impcap) << Var->getDeclName(); 10107 Diag(Var->getLocation(), diag::note_previous_decl) 10108 << Var->getDeclName(); 10109 Diag(cast<LambdaScopeInfo>(CSI)->Lambda->getLocStart(), 10110 diag::note_lambda_decl); 10111 } 10112 return true; 10113 } 10114 10115 FunctionScopesIndex--; 10116 DC = ParentDC; 10117 Explicit = false; 10118 } while (!Var->getDeclContext()->Equals(DC)); 10119 10120 // Walk back down the scope stack, computing the type of the capture at 10121 // each step, checking type-specific requirements, and adding captures if 10122 // requested. 10123 for (unsigned I = ++FunctionScopesIndex, N = FunctionScopes.size(); I != N; 10124 ++I) { 10125 CapturingScopeInfo *CSI = cast<CapturingScopeInfo>(FunctionScopes[I]); 10126 10127 // Compute the type of the capture and of a reference to the capture within 10128 // this scope. 10129 if (isa<BlockScopeInfo>(CSI)) { 10130 Expr *CopyExpr = 0; 10131 bool ByRef = false; 10132 10133 // Blocks are not allowed to capture arrays. 10134 if (CaptureType->isArrayType()) { 10135 if (BuildAndDiagnose) { 10136 Diag(Loc, diag::err_ref_array_type); 10137 Diag(Var->getLocation(), diag::note_previous_decl) 10138 << Var->getDeclName(); 10139 } 10140 return true; 10141 } 10142 10143 // Forbid the block-capture of autoreleasing variables. 10144 if (CaptureType.getObjCLifetime() == Qualifiers::OCL_Autoreleasing) { 10145 if (BuildAndDiagnose) { 10146 Diag(Loc, diag::err_arc_autoreleasing_capture) 10147 << /*block*/ 0; 10148 Diag(Var->getLocation(), diag::note_previous_decl) 10149 << Var->getDeclName(); 10150 } 10151 return true; 10152 } 10153 10154 if (HasBlocksAttr || CaptureType->isReferenceType()) { 10155 // Block capture by reference does not change the capture or 10156 // declaration reference types. 10157 ByRef = true; 10158 } else { 10159 // Block capture by copy introduces 'const'. 10160 CaptureType = CaptureType.getNonReferenceType().withConst(); 10161 DeclRefType = CaptureType; 10162 10163 if (getLangOpts().CPlusPlus && BuildAndDiagnose) { 10164 if (const RecordType *Record = DeclRefType->getAs<RecordType>()) { 10165 // The capture logic needs the destructor, so make sure we mark it. 10166 // Usually this is unnecessary because most local variables have 10167 // their destructors marked at declaration time, but parameters are 10168 // an exception because it's technically only the call site that 10169 // actually requires the destructor. 10170 if (isa<ParmVarDecl>(Var)) 10171 FinalizeVarWithDestructor(Var, Record); 10172 10173 // According to the blocks spec, the capture of a variable from 10174 // the stack requires a const copy constructor. This is not true 10175 // of the copy/move done to move a __block variable to the heap. 10176 Expr *DeclRef = new (Context) DeclRefExpr(Var, false, 10177 DeclRefType.withConst(), 10178 VK_LValue, Loc); 10179 ExprResult Result 10180 = PerformCopyInitialization( 10181 InitializedEntity::InitializeBlock(Var->getLocation(), 10182 CaptureType, false), 10183 Loc, Owned(DeclRef)); 10184 10185 // Build a full-expression copy expression if initialization 10186 // succeeded and used a non-trivial constructor. Recover from 10187 // errors by pretending that the copy isn't necessary. 10188 if (!Result.isInvalid() && 10189 !cast<CXXConstructExpr>(Result.get())->getConstructor() 10190 ->isTrivial()) { 10191 Result = MaybeCreateExprWithCleanups(Result); 10192 CopyExpr = Result.take(); 10193 } 10194 } 10195 } 10196 } 10197 10198 // Actually capture the variable. 10199 if (BuildAndDiagnose) 10200 CSI->addCapture(Var, HasBlocksAttr, ByRef, Nested, Loc, 10201 SourceLocation(), CaptureType, CopyExpr); 10202 Nested = true; 10203 continue; 10204 } 10205 10206 LambdaScopeInfo *LSI = cast<LambdaScopeInfo>(CSI); 10207 10208 // Determine whether we are capturing by reference or by value. 10209 bool ByRef = false; 10210 if (I == N - 1 && Kind != TryCapture_Implicit) { 10211 ByRef = (Kind == TryCapture_ExplicitByRef); 10212 } else { 10213 ByRef = (LSI->ImpCaptureStyle == LambdaScopeInfo::ImpCap_LambdaByref); 10214 } 10215 10216 // Compute the type of the field that will capture this variable. 10217 if (ByRef) { 10218 // C++11 [expr.prim.lambda]p15: 10219 // An entity is captured by reference if it is implicitly or 10220 // explicitly captured but not captured by copy. It is 10221 // unspecified whether additional unnamed non-static data 10222 // members are declared in the closure type for entities 10223 // captured by reference. 10224 // 10225 // FIXME: It is not clear whether we want to build an lvalue reference 10226 // to the DeclRefType or to CaptureType.getNonReferenceType(). GCC appears 10227 // to do the former, while EDG does the latter. Core issue 1249 will 10228 // clarify, but for now we follow GCC because it's a more permissive and 10229 // easily defensible position. 10230 CaptureType = Context.getLValueReferenceType(DeclRefType); 10231 } else { 10232 // C++11 [expr.prim.lambda]p14: 10233 // For each entity captured by copy, an unnamed non-static 10234 // data member is declared in the closure type. The 10235 // declaration order of these members is unspecified. The type 10236 // of such a data member is the type of the corresponding 10237 // captured entity if the entity is not a reference to an 10238 // object, or the referenced type otherwise. [Note: If the 10239 // captured entity is a reference to a function, the 10240 // corresponding data member is also a reference to a 10241 // function. - end note ] 10242 if (const ReferenceType *RefType = CaptureType->getAs<ReferenceType>()){ 10243 if (!RefType->getPointeeType()->isFunctionType()) 10244 CaptureType = RefType->getPointeeType(); 10245 } 10246 10247 // Forbid the lambda copy-capture of autoreleasing variables. 10248 if (CaptureType.getObjCLifetime() == Qualifiers::OCL_Autoreleasing) { 10249 if (BuildAndDiagnose) { 10250 Diag(Loc, diag::err_arc_autoreleasing_capture) << /*lambda*/ 1; 10251 Diag(Var->getLocation(), diag::note_previous_decl) 10252 << Var->getDeclName(); 10253 } 10254 return true; 10255 } 10256 } 10257 10258 // Capture this variable in the lambda. 10259 Expr *CopyExpr = 0; 10260 if (BuildAndDiagnose) { 10261 ExprResult Result = captureInLambda(*this, LSI, Var, CaptureType, 10262 DeclRefType, Loc); 10263 if (!Result.isInvalid()) 10264 CopyExpr = Result.take(); 10265 } 10266 10267 // Compute the type of a reference to this captured variable. 10268 if (ByRef) 10269 DeclRefType = CaptureType.getNonReferenceType(); 10270 else { 10271 // C++ [expr.prim.lambda]p5: 10272 // The closure type for a lambda-expression has a public inline 10273 // function call operator [...]. This function call operator is 10274 // declared const (9.3.1) if and only if the lambda-expression’s 10275 // parameter-declaration-clause is not followed by mutable. 10276 DeclRefType = CaptureType.getNonReferenceType(); 10277 if (!LSI->Mutable && !CaptureType->isReferenceType()) 10278 DeclRefType.addConst(); 10279 } 10280 10281 // Add the capture. 10282 if (BuildAndDiagnose) 10283 CSI->addCapture(Var, /*IsBlock=*/false, ByRef, Nested, Loc, 10284 EllipsisLoc, CaptureType, CopyExpr); 10285 Nested = true; 10286 } 10287 10288 return false; 10289} 10290 10291bool Sema::tryCaptureVariable(VarDecl *Var, SourceLocation Loc, 10292 TryCaptureKind Kind, SourceLocation EllipsisLoc) { 10293 QualType CaptureType; 10294 QualType DeclRefType; 10295 return tryCaptureVariable(Var, Loc, Kind, EllipsisLoc, 10296 /*BuildAndDiagnose=*/true, CaptureType, 10297 DeclRefType); 10298} 10299 10300QualType Sema::getCapturedDeclRefType(VarDecl *Var, SourceLocation Loc) { 10301 QualType CaptureType; 10302 QualType DeclRefType; 10303 10304 // Determine whether we can capture this variable. 10305 if (tryCaptureVariable(Var, Loc, TryCapture_Implicit, SourceLocation(), 10306 /*BuildAndDiagnose=*/false, CaptureType, DeclRefType)) 10307 return QualType(); 10308 10309 return DeclRefType; 10310} 10311 10312static void MarkVarDeclODRUsed(Sema &SemaRef, VarDecl *Var, 10313 SourceLocation Loc) { 10314 // Keep track of used but undefined variables. 10315 // FIXME: We shouldn't suppress this warning for static data members. 10316 if (Var->hasDefinition(SemaRef.Context) == VarDecl::DeclarationOnly && 10317 Var->getLinkage() != ExternalLinkage && 10318 !(Var->isStaticDataMember() && Var->hasInit())) { 10319 SourceLocation &old = SemaRef.UndefinedInternals[Var->getCanonicalDecl()]; 10320 if (old.isInvalid()) old = Loc; 10321 } 10322 10323 SemaRef.tryCaptureVariable(Var, Loc); 10324 10325 Var->setUsed(true); 10326} 10327 10328void Sema::UpdateMarkingForLValueToRValue(Expr *E) { 10329 // Per C++11 [basic.def.odr], a variable is odr-used "unless it is 10330 // an object that satisfies the requirements for appearing in a 10331 // constant expression (5.19) and the lvalue-to-rvalue conversion (4.1) 10332 // is immediately applied." This function handles the lvalue-to-rvalue 10333 // conversion part. 10334 MaybeODRUseExprs.erase(E->IgnoreParens()); 10335} 10336 10337ExprResult Sema::ActOnConstantExpression(ExprResult Res) { 10338 if (!Res.isUsable()) 10339 return Res; 10340 10341 // If a constant-expression is a reference to a variable where we delay 10342 // deciding whether it is an odr-use, just assume we will apply the 10343 // lvalue-to-rvalue conversion. In the one case where this doesn't happen 10344 // (a non-type template argument), we have special handling anyway. 10345 UpdateMarkingForLValueToRValue(Res.get()); 10346 return Res; 10347} 10348 10349void Sema::CleanupVarDeclMarking() { 10350 for (llvm::SmallPtrSetIterator<Expr*> i = MaybeODRUseExprs.begin(), 10351 e = MaybeODRUseExprs.end(); 10352 i != e; ++i) { 10353 VarDecl *Var; 10354 SourceLocation Loc; 10355 if (DeclRefExpr *DRE = dyn_cast<DeclRefExpr>(*i)) { 10356 Var = cast<VarDecl>(DRE->getDecl()); 10357 Loc = DRE->getLocation(); 10358 } else if (MemberExpr *ME = dyn_cast<MemberExpr>(*i)) { 10359 Var = cast<VarDecl>(ME->getMemberDecl()); 10360 Loc = ME->getMemberLoc(); 10361 } else { 10362 llvm_unreachable("Unexpcted expression"); 10363 } 10364 10365 MarkVarDeclODRUsed(*this, Var, Loc); 10366 } 10367 10368 MaybeODRUseExprs.clear(); 10369} 10370 10371// Mark a VarDecl referenced, and perform the necessary handling to compute 10372// odr-uses. 10373static void DoMarkVarDeclReferenced(Sema &SemaRef, SourceLocation Loc, 10374 VarDecl *Var, Expr *E) { 10375 Var->setReferenced(); 10376 10377 if (!IsPotentiallyEvaluatedContext(SemaRef)) 10378 return; 10379 10380 // Implicit instantiation of static data members of class templates. 10381 if (Var->isStaticDataMember() && Var->getInstantiatedFromStaticDataMember()) { 10382 MemberSpecializationInfo *MSInfo = Var->getMemberSpecializationInfo(); 10383 assert(MSInfo && "Missing member specialization information?"); 10384 bool AlreadyInstantiated = !MSInfo->getPointOfInstantiation().isInvalid(); 10385 if (MSInfo->getTemplateSpecializationKind() == TSK_ImplicitInstantiation && 10386 (!AlreadyInstantiated || 10387 Var->isUsableInConstantExpressions(SemaRef.Context))) { 10388 if (!AlreadyInstantiated) { 10389 // This is a modification of an existing AST node. Notify listeners. 10390 if (ASTMutationListener *L = SemaRef.getASTMutationListener()) 10391 L->StaticDataMemberInstantiated(Var); 10392 MSInfo->setPointOfInstantiation(Loc); 10393 } 10394 SourceLocation PointOfInstantiation = MSInfo->getPointOfInstantiation(); 10395 if (Var->isUsableInConstantExpressions(SemaRef.Context)) 10396 // Do not defer instantiations of variables which could be used in a 10397 // constant expression. 10398 SemaRef.InstantiateStaticDataMemberDefinition(PointOfInstantiation,Var); 10399 else 10400 SemaRef.PendingInstantiations.push_back( 10401 std::make_pair(Var, PointOfInstantiation)); 10402 } 10403 } 10404 10405 // Per C++11 [basic.def.odr], a variable is odr-used "unless it is 10406 // an object that satisfies the requirements for appearing in a 10407 // constant expression (5.19) and the lvalue-to-rvalue conversion (4.1) 10408 // is immediately applied." We check the first part here, and 10409 // Sema::UpdateMarkingForLValueToRValue deals with the second part. 10410 // Note that we use the C++11 definition everywhere because nothing in 10411 // C++03 depends on whether we get the C++03 version correct. This does not 10412 // apply to references, since they are not objects. 10413 const VarDecl *DefVD; 10414 if (E && !isa<ParmVarDecl>(Var) && !Var->getType()->isReferenceType() && 10415 Var->isUsableInConstantExpressions(SemaRef.Context) && 10416 Var->getAnyInitializer(DefVD) && DefVD->checkInitIsICE()) 10417 SemaRef.MaybeODRUseExprs.insert(E); 10418 else 10419 MarkVarDeclODRUsed(SemaRef, Var, Loc); 10420} 10421 10422/// \brief Mark a variable referenced, and check whether it is odr-used 10423/// (C++ [basic.def.odr]p2, C99 6.9p3). Note that this should not be 10424/// used directly for normal expressions referring to VarDecl. 10425void Sema::MarkVariableReferenced(SourceLocation Loc, VarDecl *Var) { 10426 DoMarkVarDeclReferenced(*this, Loc, Var, 0); 10427} 10428 10429static void MarkExprReferenced(Sema &SemaRef, SourceLocation Loc, 10430 Decl *D, Expr *E) { 10431 if (VarDecl *Var = dyn_cast<VarDecl>(D)) { 10432 DoMarkVarDeclReferenced(SemaRef, Loc, Var, E); 10433 return; 10434 } 10435 10436 SemaRef.MarkAnyDeclReferenced(Loc, D); 10437} 10438 10439/// \brief Perform reference-marking and odr-use handling for a DeclRefExpr. 10440void Sema::MarkDeclRefReferenced(DeclRefExpr *E) { 10441 MarkExprReferenced(*this, E->getLocation(), E->getDecl(), E); 10442} 10443 10444/// \brief Perform reference-marking and odr-use handling for a MemberExpr. 10445void Sema::MarkMemberReferenced(MemberExpr *E) { 10446 MarkExprReferenced(*this, E->getMemberLoc(), E->getMemberDecl(), E); 10447} 10448 10449/// \brief Perform marking for a reference to an arbitrary declaration. It 10450/// marks the declaration referenced, and performs odr-use checking for functions 10451/// and variables. This method should not be used when building an normal 10452/// expression which refers to a variable. 10453void Sema::MarkAnyDeclReferenced(SourceLocation Loc, Decl *D) { 10454 if (VarDecl *VD = dyn_cast<VarDecl>(D)) 10455 MarkVariableReferenced(Loc, VD); 10456 else if (FunctionDecl *FD = dyn_cast<FunctionDecl>(D)) 10457 MarkFunctionReferenced(Loc, FD); 10458 else 10459 D->setReferenced(); 10460} 10461 10462namespace { 10463 // Mark all of the declarations referenced 10464 // FIXME: Not fully implemented yet! We need to have a better understanding 10465 // of when we're entering 10466 class MarkReferencedDecls : public RecursiveASTVisitor<MarkReferencedDecls> { 10467 Sema &S; 10468 SourceLocation Loc; 10469 10470 public: 10471 typedef RecursiveASTVisitor<MarkReferencedDecls> Inherited; 10472 10473 MarkReferencedDecls(Sema &S, SourceLocation Loc) : S(S), Loc(Loc) { } 10474 10475 bool TraverseTemplateArgument(const TemplateArgument &Arg); 10476 bool TraverseRecordType(RecordType *T); 10477 }; 10478} 10479 10480bool MarkReferencedDecls::TraverseTemplateArgument( 10481 const TemplateArgument &Arg) { 10482 if (Arg.getKind() == TemplateArgument::Declaration) { 10483 if (Decl *D = Arg.getAsDecl()) 10484 S.MarkAnyDeclReferenced(Loc, D); 10485 } 10486 10487 return Inherited::TraverseTemplateArgument(Arg); 10488} 10489 10490bool MarkReferencedDecls::TraverseRecordType(RecordType *T) { 10491 if (ClassTemplateSpecializationDecl *Spec 10492 = dyn_cast<ClassTemplateSpecializationDecl>(T->getDecl())) { 10493 const TemplateArgumentList &Args = Spec->getTemplateArgs(); 10494 return TraverseTemplateArguments(Args.data(), Args.size()); 10495 } 10496 10497 return true; 10498} 10499 10500void Sema::MarkDeclarationsReferencedInType(SourceLocation Loc, QualType T) { 10501 MarkReferencedDecls Marker(*this, Loc); 10502 Marker.TraverseType(Context.getCanonicalType(T)); 10503} 10504 10505namespace { 10506 /// \brief Helper class that marks all of the declarations referenced by 10507 /// potentially-evaluated subexpressions as "referenced". 10508 class EvaluatedExprMarker : public EvaluatedExprVisitor<EvaluatedExprMarker> { 10509 Sema &S; 10510 bool SkipLocalVariables; 10511 10512 public: 10513 typedef EvaluatedExprVisitor<EvaluatedExprMarker> Inherited; 10514 10515 EvaluatedExprMarker(Sema &S, bool SkipLocalVariables) 10516 : Inherited(S.Context), S(S), SkipLocalVariables(SkipLocalVariables) { } 10517 10518 void VisitDeclRefExpr(DeclRefExpr *E) { 10519 // If we were asked not to visit local variables, don't. 10520 if (SkipLocalVariables) { 10521 if (VarDecl *VD = dyn_cast<VarDecl>(E->getDecl())) 10522 if (VD->hasLocalStorage()) 10523 return; 10524 } 10525 10526 S.MarkDeclRefReferenced(E); 10527 } 10528 10529 void VisitMemberExpr(MemberExpr *E) { 10530 S.MarkMemberReferenced(E); 10531 Inherited::VisitMemberExpr(E); 10532 } 10533 10534 void VisitCXXBindTemporaryExpr(CXXBindTemporaryExpr *E) { 10535 S.MarkFunctionReferenced(E->getLocStart(), 10536 const_cast<CXXDestructorDecl*>(E->getTemporary()->getDestructor())); 10537 Visit(E->getSubExpr()); 10538 } 10539 10540 void VisitCXXNewExpr(CXXNewExpr *E) { 10541 if (E->getOperatorNew()) 10542 S.MarkFunctionReferenced(E->getLocStart(), E->getOperatorNew()); 10543 if (E->getOperatorDelete()) 10544 S.MarkFunctionReferenced(E->getLocStart(), E->getOperatorDelete()); 10545 Inherited::VisitCXXNewExpr(E); 10546 } 10547 10548 void VisitCXXDeleteExpr(CXXDeleteExpr *E) { 10549 if (E->getOperatorDelete()) 10550 S.MarkFunctionReferenced(E->getLocStart(), E->getOperatorDelete()); 10551 QualType Destroyed = S.Context.getBaseElementType(E->getDestroyedType()); 10552 if (const RecordType *DestroyedRec = Destroyed->getAs<RecordType>()) { 10553 CXXRecordDecl *Record = cast<CXXRecordDecl>(DestroyedRec->getDecl()); 10554 S.MarkFunctionReferenced(E->getLocStart(), 10555 S.LookupDestructor(Record)); 10556 } 10557 10558 Inherited::VisitCXXDeleteExpr(E); 10559 } 10560 10561 void VisitCXXConstructExpr(CXXConstructExpr *E) { 10562 S.MarkFunctionReferenced(E->getLocStart(), E->getConstructor()); 10563 Inherited::VisitCXXConstructExpr(E); 10564 } 10565 10566 void VisitCXXDefaultArgExpr(CXXDefaultArgExpr *E) { 10567 Visit(E->getExpr()); 10568 } 10569 10570 void VisitImplicitCastExpr(ImplicitCastExpr *E) { 10571 Inherited::VisitImplicitCastExpr(E); 10572 10573 if (E->getCastKind() == CK_LValueToRValue) 10574 S.UpdateMarkingForLValueToRValue(E->getSubExpr()); 10575 } 10576 }; 10577} 10578 10579/// \brief Mark any declarations that appear within this expression or any 10580/// potentially-evaluated subexpressions as "referenced". 10581/// 10582/// \param SkipLocalVariables If true, don't mark local variables as 10583/// 'referenced'. 10584void Sema::MarkDeclarationsReferencedInExpr(Expr *E, 10585 bool SkipLocalVariables) { 10586 EvaluatedExprMarker(*this, SkipLocalVariables).Visit(E); 10587} 10588 10589/// \brief Emit a diagnostic that describes an effect on the run-time behavior 10590/// of the program being compiled. 10591/// 10592/// This routine emits the given diagnostic when the code currently being 10593/// type-checked is "potentially evaluated", meaning that there is a 10594/// possibility that the code will actually be executable. Code in sizeof() 10595/// expressions, code used only during overload resolution, etc., are not 10596/// potentially evaluated. This routine will suppress such diagnostics or, 10597/// in the absolutely nutty case of potentially potentially evaluated 10598/// expressions (C++ typeid), queue the diagnostic to potentially emit it 10599/// later. 10600/// 10601/// This routine should be used for all diagnostics that describe the run-time 10602/// behavior of a program, such as passing a non-POD value through an ellipsis. 10603/// Failure to do so will likely result in spurious diagnostics or failures 10604/// during overload resolution or within sizeof/alignof/typeof/typeid. 10605bool Sema::DiagRuntimeBehavior(SourceLocation Loc, const Stmt *Statement, 10606 const PartialDiagnostic &PD) { 10607 switch (ExprEvalContexts.back().Context) { 10608 case Unevaluated: 10609 // The argument will never be evaluated, so don't complain. 10610 break; 10611 10612 case ConstantEvaluated: 10613 // Relevant diagnostics should be produced by constant evaluation. 10614 break; 10615 10616 case PotentiallyEvaluated: 10617 case PotentiallyEvaluatedIfUsed: 10618 if (Statement && getCurFunctionOrMethodDecl()) { 10619 FunctionScopes.back()->PossiblyUnreachableDiags. 10620 push_back(sema::PossiblyUnreachableDiag(PD, Loc, Statement)); 10621 } 10622 else 10623 Diag(Loc, PD); 10624 10625 return true; 10626 } 10627 10628 return false; 10629} 10630 10631bool Sema::CheckCallReturnType(QualType ReturnType, SourceLocation Loc, 10632 CallExpr *CE, FunctionDecl *FD) { 10633 if (ReturnType->isVoidType() || !ReturnType->isIncompleteType()) 10634 return false; 10635 10636 // If we're inside a decltype's expression, don't check for a valid return 10637 // type or construct temporaries until we know whether this is the last call. 10638 if (ExprEvalContexts.back().IsDecltype) { 10639 ExprEvalContexts.back().DelayedDecltypeCalls.push_back(CE); 10640 return false; 10641 } 10642 10643 PartialDiagnostic Note = 10644 FD ? PDiag(diag::note_function_with_incomplete_return_type_declared_here) 10645 << FD->getDeclName() : PDiag(); 10646 SourceLocation NoteLoc = FD ? FD->getLocation() : SourceLocation(); 10647 10648 if (RequireCompleteType(Loc, ReturnType, 10649 FD ? 10650 PDiag(diag::err_call_function_incomplete_return) 10651 << CE->getSourceRange() << FD->getDeclName() : 10652 PDiag(diag::err_call_incomplete_return) 10653 << CE->getSourceRange(), 10654 std::make_pair(NoteLoc, Note))) 10655 return true; 10656 10657 return false; 10658} 10659 10660// Diagnose the s/=/==/ and s/\|=/!=/ typos. Note that adding parentheses 10661// will prevent this condition from triggering, which is what we want. 10662void Sema::DiagnoseAssignmentAsCondition(Expr *E) { 10663 SourceLocation Loc; 10664 10665 unsigned diagnostic = diag::warn_condition_is_assignment; 10666 bool IsOrAssign = false; 10667 10668 if (BinaryOperator *Op = dyn_cast<BinaryOperator>(E)) { 10669 if (Op->getOpcode() != BO_Assign && Op->getOpcode() != BO_OrAssign) 10670 return; 10671 10672 IsOrAssign = Op->getOpcode() == BO_OrAssign; 10673 10674 // Greylist some idioms by putting them into a warning subcategory. 10675 if (ObjCMessageExpr *ME 10676 = dyn_cast<ObjCMessageExpr>(Op->getRHS()->IgnoreParenCasts())) { 10677 Selector Sel = ME->getSelector(); 10678 10679 // self = [<foo> init...] 10680 if (isSelfExpr(Op->getLHS()) && Sel.getNameForSlot(0).startswith("init")) 10681 diagnostic = diag::warn_condition_is_idiomatic_assignment; 10682 10683 // <foo> = [<bar> nextObject] 10684 else if (Sel.isUnarySelector() && Sel.getNameForSlot(0) == "nextObject") 10685 diagnostic = diag::warn_condition_is_idiomatic_assignment; 10686 } 10687 10688 Loc = Op->getOperatorLoc(); 10689 } else if (CXXOperatorCallExpr *Op = dyn_cast<CXXOperatorCallExpr>(E)) { 10690 if (Op->getOperator() != OO_Equal && Op->getOperator() != OO_PipeEqual) 10691 return; 10692 10693 IsOrAssign = Op->getOperator() == OO_PipeEqual; 10694 Loc = Op->getOperatorLoc(); 10695 } else { 10696 // Not an assignment. 10697 return; 10698 } 10699 10700 Diag(Loc, diagnostic) << E->getSourceRange(); 10701 10702 SourceLocation Open = E->getLocStart(); 10703 SourceLocation Close = PP.getLocForEndOfToken(E->getSourceRange().getEnd()); 10704 Diag(Loc, diag::note_condition_assign_silence) 10705 << FixItHint::CreateInsertion(Open, "(") 10706 << FixItHint::CreateInsertion(Close, ")"); 10707 10708 if (IsOrAssign) 10709 Diag(Loc, diag::note_condition_or_assign_to_comparison) 10710 << FixItHint::CreateReplacement(Loc, "!="); 10711 else 10712 Diag(Loc, diag::note_condition_assign_to_comparison) 10713 << FixItHint::CreateReplacement(Loc, "=="); 10714} 10715 10716/// \brief Redundant parentheses over an equality comparison can indicate 10717/// that the user intended an assignment used as condition. 10718void Sema::DiagnoseEqualityWithExtraParens(ParenExpr *ParenE) { 10719 // Don't warn if the parens came from a macro. 10720 SourceLocation parenLoc = ParenE->getLocStart(); 10721 if (parenLoc.isInvalid() || parenLoc.isMacroID()) 10722 return; 10723 // Don't warn for dependent expressions. 10724 if (ParenE->isTypeDependent()) 10725 return; 10726 10727 Expr *E = ParenE->IgnoreParens(); 10728 10729 if (BinaryOperator *opE = dyn_cast<BinaryOperator>(E)) 10730 if (opE->getOpcode() == BO_EQ && 10731 opE->getLHS()->IgnoreParenImpCasts()->isModifiableLvalue(Context) 10732 == Expr::MLV_Valid) { 10733 SourceLocation Loc = opE->getOperatorLoc(); 10734 10735 Diag(Loc, diag::warn_equality_with_extra_parens) << E->getSourceRange(); 10736 SourceRange ParenERange = ParenE->getSourceRange(); 10737 Diag(Loc, diag::note_equality_comparison_silence) 10738 << FixItHint::CreateRemoval(ParenERange.getBegin()) 10739 << FixItHint::CreateRemoval(ParenERange.getEnd()); 10740 Diag(Loc, diag::note_equality_comparison_to_assign) 10741 << FixItHint::CreateReplacement(Loc, "="); 10742 } 10743} 10744 10745ExprResult Sema::CheckBooleanCondition(Expr *E, SourceLocation Loc) { 10746 DiagnoseAssignmentAsCondition(E); 10747 if (ParenExpr *parenE = dyn_cast<ParenExpr>(E)) 10748 DiagnoseEqualityWithExtraParens(parenE); 10749 10750 ExprResult result = CheckPlaceholderExpr(E); 10751 if (result.isInvalid()) return ExprError(); 10752 E = result.take(); 10753 10754 if (!E->isTypeDependent()) { 10755 if (getLangOpts().CPlusPlus) 10756 return CheckCXXBooleanCondition(E); // C++ 6.4p4 10757 10758 ExprResult ERes = DefaultFunctionArrayLvalueConversion(E); 10759 if (ERes.isInvalid()) 10760 return ExprError(); 10761 E = ERes.take(); 10762 10763 QualType T = E->getType(); 10764 if (!T->isScalarType()) { // C99 6.8.4.1p1 10765 Diag(Loc, diag::err_typecheck_statement_requires_scalar) 10766 << T << E->getSourceRange(); 10767 return ExprError(); 10768 } 10769 } 10770 10771 return Owned(E); 10772} 10773 10774ExprResult Sema::ActOnBooleanCondition(Scope *S, SourceLocation Loc, 10775 Expr *SubExpr) { 10776 if (!SubExpr) 10777 return ExprError(); 10778 10779 return CheckBooleanCondition(SubExpr, Loc); 10780} 10781 10782namespace { 10783 /// A visitor for rebuilding a call to an __unknown_any expression 10784 /// to have an appropriate type. 10785 struct RebuildUnknownAnyFunction 10786 : StmtVisitor<RebuildUnknownAnyFunction, ExprResult> { 10787 10788 Sema &S; 10789 10790 RebuildUnknownAnyFunction(Sema &S) : S(S) {} 10791 10792 ExprResult VisitStmt(Stmt *S) { 10793 llvm_unreachable("unexpected statement!"); 10794 } 10795 10796 ExprResult VisitExpr(Expr *E) { 10797 S.Diag(E->getExprLoc(), diag::err_unsupported_unknown_any_call) 10798 << E->getSourceRange(); 10799 return ExprError(); 10800 } 10801 10802 /// Rebuild an expression which simply semantically wraps another 10803 /// expression which it shares the type and value kind of. 10804 template <class T> ExprResult rebuildSugarExpr(T *E) { 10805 ExprResult SubResult = Visit(E->getSubExpr()); 10806 if (SubResult.isInvalid()) return ExprError(); 10807 10808 Expr *SubExpr = SubResult.take(); 10809 E->setSubExpr(SubExpr); 10810 E->setType(SubExpr->getType()); 10811 E->setValueKind(SubExpr->getValueKind()); 10812 assert(E->getObjectKind() == OK_Ordinary); 10813 return E; 10814 } 10815 10816 ExprResult VisitParenExpr(ParenExpr *E) { 10817 return rebuildSugarExpr(E); 10818 } 10819 10820 ExprResult VisitUnaryExtension(UnaryOperator *E) { 10821 return rebuildSugarExpr(E); 10822 } 10823 10824 ExprResult VisitUnaryAddrOf(UnaryOperator *E) { 10825 ExprResult SubResult = Visit(E->getSubExpr()); 10826 if (SubResult.isInvalid()) return ExprError(); 10827 10828 Expr *SubExpr = SubResult.take(); 10829 E->setSubExpr(SubExpr); 10830 E->setType(S.Context.getPointerType(SubExpr->getType())); 10831 assert(E->getValueKind() == VK_RValue); 10832 assert(E->getObjectKind() == OK_Ordinary); 10833 return E; 10834 } 10835 10836 ExprResult resolveDecl(Expr *E, ValueDecl *VD) { 10837 if (!isa<FunctionDecl>(VD)) return VisitExpr(E); 10838 10839 E->setType(VD->getType()); 10840 10841 assert(E->getValueKind() == VK_RValue); 10842 if (S.getLangOpts().CPlusPlus && 10843 !(isa<CXXMethodDecl>(VD) && 10844 cast<CXXMethodDecl>(VD)->isInstance())) 10845 E->setValueKind(VK_LValue); 10846 10847 return E; 10848 } 10849 10850 ExprResult VisitMemberExpr(MemberExpr *E) { 10851 return resolveDecl(E, E->getMemberDecl()); 10852 } 10853 10854 ExprResult VisitDeclRefExpr(DeclRefExpr *E) { 10855 return resolveDecl(E, E->getDecl()); 10856 } 10857 }; 10858} 10859 10860/// Given a function expression of unknown-any type, try to rebuild it 10861/// to have a function type. 10862static ExprResult rebuildUnknownAnyFunction(Sema &S, Expr *FunctionExpr) { 10863 ExprResult Result = RebuildUnknownAnyFunction(S).Visit(FunctionExpr); 10864 if (Result.isInvalid()) return ExprError(); 10865 return S.DefaultFunctionArrayConversion(Result.take()); 10866} 10867 10868namespace { 10869 /// A visitor for rebuilding an expression of type __unknown_anytype 10870 /// into one which resolves the type directly on the referring 10871 /// expression. Strict preservation of the original source 10872 /// structure is not a goal. 10873 struct RebuildUnknownAnyExpr 10874 : StmtVisitor<RebuildUnknownAnyExpr, ExprResult> { 10875 10876 Sema &S; 10877 10878 /// The current destination type. 10879 QualType DestType; 10880 10881 RebuildUnknownAnyExpr(Sema &S, QualType CastType) 10882 : S(S), DestType(CastType) {} 10883 10884 ExprResult VisitStmt(Stmt *S) { 10885 llvm_unreachable("unexpected statement!"); 10886 } 10887 10888 ExprResult VisitExpr(Expr *E) { 10889 S.Diag(E->getExprLoc(), diag::err_unsupported_unknown_any_expr) 10890 << E->getSourceRange(); 10891 return ExprError(); 10892 } 10893 10894 ExprResult VisitCallExpr(CallExpr *E); 10895 ExprResult VisitObjCMessageExpr(ObjCMessageExpr *E); 10896 10897 /// Rebuild an expression which simply semantically wraps another 10898 /// expression which it shares the type and value kind of. 10899 template <class T> ExprResult rebuildSugarExpr(T *E) { 10900 ExprResult SubResult = Visit(E->getSubExpr()); 10901 if (SubResult.isInvalid()) return ExprError(); 10902 Expr *SubExpr = SubResult.take(); 10903 E->setSubExpr(SubExpr); 10904 E->setType(SubExpr->getType()); 10905 E->setValueKind(SubExpr->getValueKind()); 10906 assert(E->getObjectKind() == OK_Ordinary); 10907 return E; 10908 } 10909 10910 ExprResult VisitParenExpr(ParenExpr *E) { 10911 return rebuildSugarExpr(E); 10912 } 10913 10914 ExprResult VisitUnaryExtension(UnaryOperator *E) { 10915 return rebuildSugarExpr(E); 10916 } 10917 10918 ExprResult VisitUnaryAddrOf(UnaryOperator *E) { 10919 const PointerType *Ptr = DestType->getAs<PointerType>(); 10920 if (!Ptr) { 10921 S.Diag(E->getOperatorLoc(), diag::err_unknown_any_addrof) 10922 << E->getSourceRange(); 10923 return ExprError(); 10924 } 10925 assert(E->getValueKind() == VK_RValue); 10926 assert(E->getObjectKind() == OK_Ordinary); 10927 E->setType(DestType); 10928 10929 // Build the sub-expression as if it were an object of the pointee type. 10930 DestType = Ptr->getPointeeType(); 10931 ExprResult SubResult = Visit(E->getSubExpr()); 10932 if (SubResult.isInvalid()) return ExprError(); 10933 E->setSubExpr(SubResult.take()); 10934 return E; 10935 } 10936 10937 ExprResult VisitImplicitCastExpr(ImplicitCastExpr *E); 10938 10939 ExprResult resolveDecl(Expr *E, ValueDecl *VD); 10940 10941 ExprResult VisitMemberExpr(MemberExpr *E) { 10942 return resolveDecl(E, E->getMemberDecl()); 10943 } 10944 10945 ExprResult VisitDeclRefExpr(DeclRefExpr *E) { 10946 return resolveDecl(E, E->getDecl()); 10947 } 10948 }; 10949} 10950 10951/// Rebuilds a call expression which yielded __unknown_anytype. 10952ExprResult RebuildUnknownAnyExpr::VisitCallExpr(CallExpr *E) { 10953 Expr *CalleeExpr = E->getCallee(); 10954 10955 enum FnKind { 10956 FK_MemberFunction, 10957 FK_FunctionPointer, 10958 FK_BlockPointer 10959 }; 10960 10961 FnKind Kind; 10962 QualType CalleeType = CalleeExpr->getType(); 10963 if (CalleeType == S.Context.BoundMemberTy) { 10964 assert(isa<CXXMemberCallExpr>(E) || isa<CXXOperatorCallExpr>(E)); 10965 Kind = FK_MemberFunction; 10966 CalleeType = Expr::findBoundMemberType(CalleeExpr); 10967 } else if (const PointerType *Ptr = CalleeType->getAs<PointerType>()) { 10968 CalleeType = Ptr->getPointeeType(); 10969 Kind = FK_FunctionPointer; 10970 } else { 10971 CalleeType = CalleeType->castAs<BlockPointerType>()->getPointeeType(); 10972 Kind = FK_BlockPointer; 10973 } 10974 const FunctionType *FnType = CalleeType->castAs<FunctionType>(); 10975 10976 // Verify that this is a legal result type of a function. 10977 if (DestType->isArrayType() || DestType->isFunctionType()) { 10978 unsigned diagID = diag::err_func_returning_array_function; 10979 if (Kind == FK_BlockPointer) 10980 diagID = diag::err_block_returning_array_function; 10981 10982 S.Diag(E->getExprLoc(), diagID) 10983 << DestType->isFunctionType() << DestType; 10984 return ExprError(); 10985 } 10986 10987 // Otherwise, go ahead and set DestType as the call's result. 10988 E->setType(DestType.getNonLValueExprType(S.Context)); 10989 E->setValueKind(Expr::getValueKindForType(DestType)); 10990 assert(E->getObjectKind() == OK_Ordinary); 10991 10992 // Rebuild the function type, replacing the result type with DestType. 10993 if (const FunctionProtoType *Proto = dyn_cast<FunctionProtoType>(FnType)) 10994 DestType = S.Context.getFunctionType(DestType, 10995 Proto->arg_type_begin(), 10996 Proto->getNumArgs(), 10997 Proto->getExtProtoInfo()); 10998 else 10999 DestType = S.Context.getFunctionNoProtoType(DestType, 11000 FnType->getExtInfo()); 11001 11002 // Rebuild the appropriate pointer-to-function type. 11003 switch (Kind) { 11004 case FK_MemberFunction: 11005 // Nothing to do. 11006 break; 11007 11008 case FK_FunctionPointer: 11009 DestType = S.Context.getPointerType(DestType); 11010 break; 11011 11012 case FK_BlockPointer: 11013 DestType = S.Context.getBlockPointerType(DestType); 11014 break; 11015 } 11016 11017 // Finally, we can recurse. 11018 ExprResult CalleeResult = Visit(CalleeExpr); 11019 if (!CalleeResult.isUsable()) return ExprError(); 11020 E->setCallee(CalleeResult.take()); 11021 11022 // Bind a temporary if necessary. 11023 return S.MaybeBindToTemporary(E); 11024} 11025 11026ExprResult RebuildUnknownAnyExpr::VisitObjCMessageExpr(ObjCMessageExpr *E) { 11027 // Verify that this is a legal result type of a call. 11028 if (DestType->isArrayType() || DestType->isFunctionType()) { 11029 S.Diag(E->getExprLoc(), diag::err_func_returning_array_function) 11030 << DestType->isFunctionType() << DestType; 11031 return ExprError(); 11032 } 11033 11034 // Rewrite the method result type if available. 11035 if (ObjCMethodDecl *Method = E->getMethodDecl()) { 11036 assert(Method->getResultType() == S.Context.UnknownAnyTy); 11037 Method->setResultType(DestType); 11038 } 11039 11040 // Change the type of the message. 11041 E->setType(DestType.getNonReferenceType()); 11042 E->setValueKind(Expr::getValueKindForType(DestType)); 11043 11044 return S.MaybeBindToTemporary(E); 11045} 11046 11047ExprResult RebuildUnknownAnyExpr::VisitImplicitCastExpr(ImplicitCastExpr *E) { 11048 // The only case we should ever see here is a function-to-pointer decay. 11049 if (E->getCastKind() == CK_FunctionToPointerDecay) { 11050 assert(E->getValueKind() == VK_RValue); 11051 assert(E->getObjectKind() == OK_Ordinary); 11052 11053 E->setType(DestType); 11054 11055 // Rebuild the sub-expression as the pointee (function) type. 11056 DestType = DestType->castAs<PointerType>()->getPointeeType(); 11057 11058 ExprResult Result = Visit(E->getSubExpr()); 11059 if (!Result.isUsable()) return ExprError(); 11060 11061 E->setSubExpr(Result.take()); 11062 return S.Owned(E); 11063 } else if (E->getCastKind() == CK_LValueToRValue) { 11064 assert(E->getValueKind() == VK_RValue); 11065 assert(E->getObjectKind() == OK_Ordinary); 11066 11067 assert(isa<BlockPointerType>(E->getType())); 11068 11069 E->setType(DestType); 11070 11071 // The sub-expression has to be a lvalue reference, so rebuild it as such. 11072 DestType = S.Context.getLValueReferenceType(DestType); 11073 11074 ExprResult Result = Visit(E->getSubExpr()); 11075 if (!Result.isUsable()) return ExprError(); 11076 11077 E->setSubExpr(Result.take()); 11078 return S.Owned(E); 11079 } else { 11080 llvm_unreachable("Unhandled cast type!"); 11081 } 11082} 11083 11084ExprResult RebuildUnknownAnyExpr::resolveDecl(Expr *E, ValueDecl *VD) { 11085 ExprValueKind ValueKind = VK_LValue; 11086 QualType Type = DestType; 11087 11088 // We know how to make this work for certain kinds of decls: 11089 11090 // - functions 11091 if (FunctionDecl *FD = dyn_cast<FunctionDecl>(VD)) { 11092 if (const PointerType *Ptr = Type->getAs<PointerType>()) { 11093 DestType = Ptr->getPointeeType(); 11094 ExprResult Result = resolveDecl(E, VD); 11095 if (Result.isInvalid()) return ExprError(); 11096 return S.ImpCastExprToType(Result.take(), Type, 11097 CK_FunctionToPointerDecay, VK_RValue); 11098 } 11099 11100 if (!Type->isFunctionType()) { 11101 S.Diag(E->getExprLoc(), diag::err_unknown_any_function) 11102 << VD << E->getSourceRange(); 11103 return ExprError(); 11104 } 11105 11106 if (CXXMethodDecl *MD = dyn_cast<CXXMethodDecl>(FD)) 11107 if (MD->isInstance()) { 11108 ValueKind = VK_RValue; 11109 Type = S.Context.BoundMemberTy; 11110 } 11111 11112 // Function references aren't l-values in C. 11113 if (!S.getLangOpts().CPlusPlus) 11114 ValueKind = VK_RValue; 11115 11116 // - variables 11117 } else if (isa<VarDecl>(VD)) { 11118 if (const ReferenceType *RefTy = Type->getAs<ReferenceType>()) { 11119 Type = RefTy->getPointeeType(); 11120 } else if (Type->isFunctionType()) { 11121 S.Diag(E->getExprLoc(), diag::err_unknown_any_var_function_type) 11122 << VD << E->getSourceRange(); 11123 return ExprError(); 11124 } 11125 11126 // - nothing else 11127 } else { 11128 S.Diag(E->getExprLoc(), diag::err_unsupported_unknown_any_decl) 11129 << VD << E->getSourceRange(); 11130 return ExprError(); 11131 } 11132 11133 VD->setType(DestType); 11134 E->setType(Type); 11135 E->setValueKind(ValueKind); 11136 return S.Owned(E); 11137} 11138 11139/// Check a cast of an unknown-any type. We intentionally only 11140/// trigger this for C-style casts. 11141ExprResult Sema::checkUnknownAnyCast(SourceRange TypeRange, QualType CastType, 11142 Expr *CastExpr, CastKind &CastKind, 11143 ExprValueKind &VK, CXXCastPath &Path) { 11144 // Rewrite the casted expression from scratch. 11145 ExprResult result = RebuildUnknownAnyExpr(*this, CastType).Visit(CastExpr); 11146 if (!result.isUsable()) return ExprError(); 11147 11148 CastExpr = result.take(); 11149 VK = CastExpr->getValueKind(); 11150 CastKind = CK_NoOp; 11151 11152 return CastExpr; 11153} 11154 11155ExprResult Sema::forceUnknownAnyToType(Expr *E, QualType ToType) { 11156 return RebuildUnknownAnyExpr(*this, ToType).Visit(E); 11157} 11158 11159static ExprResult diagnoseUnknownAnyExpr(Sema &S, Expr *E) { 11160 Expr *orig = E; 11161 unsigned diagID = diag::err_uncasted_use_of_unknown_any; 11162 while (true) { 11163 E = E->IgnoreParenImpCasts(); 11164 if (CallExpr *call = dyn_cast<CallExpr>(E)) { 11165 E = call->getCallee(); 11166 diagID = diag::err_uncasted_call_of_unknown_any; 11167 } else { 11168 break; 11169 } 11170 } 11171 11172 SourceLocation loc; 11173 NamedDecl *d; 11174 if (DeclRefExpr *ref = dyn_cast<DeclRefExpr>(E)) { 11175 loc = ref->getLocation(); 11176 d = ref->getDecl(); 11177 } else if (MemberExpr *mem = dyn_cast<MemberExpr>(E)) { 11178 loc = mem->getMemberLoc(); 11179 d = mem->getMemberDecl(); 11180 } else if (ObjCMessageExpr *msg = dyn_cast<ObjCMessageExpr>(E)) { 11181 diagID = diag::err_uncasted_call_of_unknown_any; 11182 loc = msg->getSelectorStartLoc(); 11183 d = msg->getMethodDecl(); 11184 if (!d) { 11185 S.Diag(loc, diag::err_uncasted_send_to_unknown_any_method) 11186 << static_cast<unsigned>(msg->isClassMessage()) << msg->getSelector() 11187 << orig->getSourceRange(); 11188 return ExprError(); 11189 } 11190 } else { 11191 S.Diag(E->getExprLoc(), diag::err_unsupported_unknown_any_expr) 11192 << E->getSourceRange(); 11193 return ExprError(); 11194 } 11195 11196 S.Diag(loc, diagID) << d << orig->getSourceRange(); 11197 11198 // Never recoverable. 11199 return ExprError(); 11200} 11201 11202/// Check for operands with placeholder types and complain if found. 11203/// Returns true if there was an error and no recovery was possible. 11204ExprResult Sema::CheckPlaceholderExpr(Expr *E) { 11205 const BuiltinType *placeholderType = E->getType()->getAsPlaceholderType(); 11206 if (!placeholderType) return Owned(E); 11207 11208 switch (placeholderType->getKind()) { 11209 11210 // Overloaded expressions. 11211 case BuiltinType::Overload: { 11212 // Try to resolve a single function template specialization. 11213 // This is obligatory. 11214 ExprResult result = Owned(E); 11215 if (ResolveAndFixSingleFunctionTemplateSpecialization(result, false)) { 11216 return result; 11217 11218 // If that failed, try to recover with a call. 11219 } else { 11220 tryToRecoverWithCall(result, PDiag(diag::err_ovl_unresolvable), 11221 /*complain*/ true); 11222 return result; 11223 } 11224 } 11225 11226 // Bound member functions. 11227 case BuiltinType::BoundMember: { 11228 ExprResult result = Owned(E); 11229 tryToRecoverWithCall(result, PDiag(diag::err_bound_member_function), 11230 /*complain*/ true); 11231 return result; 11232 } 11233 11234 // ARC unbridged casts. 11235 case BuiltinType::ARCUnbridgedCast: { 11236 Expr *realCast = stripARCUnbridgedCast(E); 11237 diagnoseARCUnbridgedCast(realCast); 11238 return Owned(realCast); 11239 } 11240 11241 // Expressions of unknown type. 11242 case BuiltinType::UnknownAny: 11243 return diagnoseUnknownAnyExpr(*this, E); 11244 11245 // Pseudo-objects. 11246 case BuiltinType::PseudoObject: 11247 return checkPseudoObjectRValue(E); 11248 11249 // Everything else should be impossible. 11250#define BUILTIN_TYPE(Id, SingletonId) \ 11251 case BuiltinType::Id: 11252#define PLACEHOLDER_TYPE(Id, SingletonId) 11253#include "clang/AST/BuiltinTypes.def" 11254 break; 11255 } 11256 11257 llvm_unreachable("invalid placeholder type!"); 11258} 11259 11260bool Sema::CheckCaseExpression(Expr *E) { 11261 if (E->isTypeDependent()) 11262 return true; 11263 if (E->isValueDependent() || E->isIntegerConstantExpr(Context)) 11264 return E->getType()->isIntegralOrEnumerationType(); 11265 return false; 11266} 11267 11268/// ActOnObjCBoolLiteral - Parse {__objc_yes,__objc_no} literals. 11269ExprResult 11270Sema::ActOnObjCBoolLiteral(SourceLocation OpLoc, tok::TokenKind Kind) { 11271 assert((Kind == tok::kw___objc_yes || Kind == tok::kw___objc_no) && 11272 "Unknown Objective-C Boolean value!"); 11273 return Owned(new (Context) ObjCBoolLiteralExpr(Kind == tok::kw___objc_yes, 11274 Context.ObjCBuiltinBoolTy, OpLoc)); 11275} 11276