SemaExpr.cpp revision d2615cc53b916e8aae45783ca7113b93de515ce3
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 "TreeTransform.h" 16#include "clang/AST/ASTConsumer.h" 17#include "clang/AST/ASTContext.h" 18#include "clang/AST/ASTMutationListener.h" 19#include "clang/AST/CXXInheritance.h" 20#include "clang/AST/DeclObjC.h" 21#include "clang/AST/DeclTemplate.h" 22#include "clang/AST/EvaluatedExprVisitor.h" 23#include "clang/AST/Expr.h" 24#include "clang/AST/ExprCXX.h" 25#include "clang/AST/ExprObjC.h" 26#include "clang/AST/RecursiveASTVisitor.h" 27#include "clang/AST/TypeLoc.h" 28#include "clang/Basic/PartialDiagnostic.h" 29#include "clang/Basic/SourceManager.h" 30#include "clang/Basic/TargetInfo.h" 31#include "clang/Lex/LiteralSupport.h" 32#include "clang/Lex/Preprocessor.h" 33#include "clang/Sema/AnalysisBasedWarnings.h" 34#include "clang/Sema/DeclSpec.h" 35#include "clang/Sema/DelayedDiagnostic.h" 36#include "clang/Sema/Designator.h" 37#include "clang/Sema/Initialization.h" 38#include "clang/Sema/Lookup.h" 39#include "clang/Sema/ParsedTemplate.h" 40#include "clang/Sema/Scope.h" 41#include "clang/Sema/ScopeInfo.h" 42#include "clang/Sema/SemaFixItUtils.h" 43#include "clang/Sema/Template.h" 44using namespace clang; 45using namespace sema; 46 47/// \brief Determine whether the use of this declaration is valid, without 48/// emitting diagnostics. 49bool Sema::CanUseDecl(NamedDecl *D) { 50 // See if this is an auto-typed variable whose initializer we are parsing. 51 if (ParsingInitForAutoVars.count(D)) 52 return false; 53 54 // See if this is a deleted function. 55 if (FunctionDecl *FD = dyn_cast<FunctionDecl>(D)) { 56 if (FD->isDeleted()) 57 return false; 58 } 59 60 // See if this function is unavailable. 61 if (D->getAvailability() == AR_Unavailable && 62 cast<Decl>(CurContext)->getAvailability() != AR_Unavailable) 63 return false; 64 65 return true; 66} 67 68static void DiagnoseUnusedOfDecl(Sema &S, NamedDecl *D, SourceLocation Loc) { 69 // Warn if this is used but marked unused. 70 if (D->hasAttr<UnusedAttr>()) { 71 const Decl *DC = cast<Decl>(S.getCurObjCLexicalContext()); 72 if (!DC->hasAttr<UnusedAttr>()) 73 S.Diag(Loc, diag::warn_used_but_marked_unused) << D->getDeclName(); 74 } 75} 76 77static AvailabilityResult DiagnoseAvailabilityOfDecl(Sema &S, 78 NamedDecl *D, SourceLocation Loc, 79 const ObjCInterfaceDecl *UnknownObjCClass) { 80 // See if this declaration is unavailable or deprecated. 81 std::string Message; 82 AvailabilityResult Result = D->getAvailability(&Message); 83 if (const EnumConstantDecl *ECD = dyn_cast<EnumConstantDecl>(D)) 84 if (Result == AR_Available) { 85 const DeclContext *DC = ECD->getDeclContext(); 86 if (const EnumDecl *TheEnumDecl = dyn_cast<EnumDecl>(DC)) 87 Result = TheEnumDecl->getAvailability(&Message); 88 } 89 90 const ObjCPropertyDecl *ObjCPDecl = 0; 91 if (Result == AR_Deprecated || Result == AR_Unavailable) { 92 if (const ObjCMethodDecl *MD = dyn_cast<ObjCMethodDecl>(D)) { 93 if (const ObjCPropertyDecl *PD = MD->findPropertyDecl()) { 94 AvailabilityResult PDeclResult = PD->getAvailability(0); 95 if (PDeclResult == Result) 96 ObjCPDecl = PD; 97 } 98 } 99 } 100 101 switch (Result) { 102 case AR_Available: 103 case AR_NotYetIntroduced: 104 break; 105 106 case AR_Deprecated: 107 S.EmitDeprecationWarning(D, Message, Loc, UnknownObjCClass, ObjCPDecl); 108 break; 109 110 case AR_Unavailable: 111 if (S.getCurContextAvailability() != AR_Unavailable) { 112 if (Message.empty()) { 113 if (!UnknownObjCClass) { 114 S.Diag(Loc, diag::err_unavailable) << D->getDeclName(); 115 if (ObjCPDecl) 116 S.Diag(ObjCPDecl->getLocation(), diag::note_property_attribute) 117 << ObjCPDecl->getDeclName() << 1; 118 } 119 else 120 S.Diag(Loc, diag::warn_unavailable_fwdclass_message) 121 << D->getDeclName(); 122 } 123 else 124 S.Diag(Loc, diag::err_unavailable_message) 125 << D->getDeclName() << Message; 126 S.Diag(D->getLocation(), diag::note_unavailable_here) 127 << isa<FunctionDecl>(D) << false; 128 if (ObjCPDecl) 129 S.Diag(ObjCPDecl->getLocation(), diag::note_property_attribute) 130 << ObjCPDecl->getDeclName() << 1; 131 } 132 break; 133 } 134 return Result; 135} 136 137/// \brief Emit a note explaining that this function is deleted or unavailable. 138void Sema::NoteDeletedFunction(FunctionDecl *Decl) { 139 CXXMethodDecl *Method = dyn_cast<CXXMethodDecl>(Decl); 140 141 if (Method && Method->isDeleted() && !Method->isDeletedAsWritten()) { 142 // If the method was explicitly defaulted, point at that declaration. 143 if (!Method->isImplicit()) 144 Diag(Decl->getLocation(), diag::note_implicitly_deleted); 145 146 // Try to diagnose why this special member function was implicitly 147 // deleted. This might fail, if that reason no longer applies. 148 CXXSpecialMember CSM = getSpecialMember(Method); 149 if (CSM != CXXInvalid) 150 ShouldDeleteSpecialMember(Method, CSM, /*Diagnose=*/true); 151 152 return; 153 } 154 155 Diag(Decl->getLocation(), diag::note_unavailable_here) 156 << 1 << Decl->isDeleted(); 157} 158 159/// \brief Determine whether a FunctionDecl was ever declared with an 160/// explicit storage class. 161static bool hasAnyExplicitStorageClass(const FunctionDecl *D) { 162 for (FunctionDecl::redecl_iterator I = D->redecls_begin(), 163 E = D->redecls_end(); 164 I != E; ++I) { 165 if (I->getStorageClass() != SC_None) 166 return true; 167 } 168 return false; 169} 170 171/// \brief Check whether we're in an extern inline function and referring to a 172/// variable or function with internal linkage (C11 6.7.4p3). 173/// 174/// This is only a warning because we used to silently accept this code, but 175/// in many cases it will not behave correctly. This is not enabled in C++ mode 176/// because the restriction language is a bit weaker (C++11 [basic.def.odr]p6) 177/// and so while there may still be user mistakes, most of the time we can't 178/// prove that there are errors. 179static void diagnoseUseOfInternalDeclInInlineFunction(Sema &S, 180 const NamedDecl *D, 181 SourceLocation Loc) { 182 // This is disabled under C++; there are too many ways for this to fire in 183 // contexts where the warning is a false positive, or where it is technically 184 // correct but benign. 185 if (S.getLangOpts().CPlusPlus) 186 return; 187 188 // Check if this is an inlined function or method. 189 FunctionDecl *Current = S.getCurFunctionDecl(); 190 if (!Current) 191 return; 192 if (!Current->isInlined()) 193 return; 194 if (Current->getLinkage() != ExternalLinkage) 195 return; 196 197 // Check if the decl has internal linkage. 198 if (D->getLinkage() != InternalLinkage) 199 return; 200 201 // Downgrade from ExtWarn to Extension if 202 // (1) the supposedly external inline function is in the main file, 203 // and probably won't be included anywhere else. 204 // (2) the thing we're referencing is a pure function. 205 // (3) the thing we're referencing is another inline function. 206 // This last can give us false negatives, but it's better than warning on 207 // wrappers for simple C library functions. 208 const FunctionDecl *UsedFn = dyn_cast<FunctionDecl>(D); 209 bool DowngradeWarning = S.getSourceManager().isFromMainFile(Loc); 210 if (!DowngradeWarning && UsedFn) 211 DowngradeWarning = UsedFn->isInlined() || UsedFn->hasAttr<ConstAttr>(); 212 213 S.Diag(Loc, DowngradeWarning ? diag::ext_internal_in_extern_inline 214 : diag::warn_internal_in_extern_inline) 215 << /*IsVar=*/!UsedFn << D; 216 217 S.MaybeSuggestAddingStaticToDecl(Current); 218 219 S.Diag(D->getCanonicalDecl()->getLocation(), 220 diag::note_internal_decl_declared_here) 221 << D; 222} 223 224void Sema::MaybeSuggestAddingStaticToDecl(const FunctionDecl *Cur) { 225 const FunctionDecl *First = Cur->getFirstDeclaration(); 226 227 // Suggest "static" on the function, if possible. 228 if (!hasAnyExplicitStorageClass(First)) { 229 SourceLocation DeclBegin = First->getSourceRange().getBegin(); 230 Diag(DeclBegin, diag::note_convert_inline_to_static) 231 << Cur << FixItHint::CreateInsertion(DeclBegin, "static "); 232 } 233} 234 235/// \brief Determine whether the use of this declaration is valid, and 236/// emit any corresponding diagnostics. 237/// 238/// This routine diagnoses various problems with referencing 239/// declarations that can occur when using a declaration. For example, 240/// it might warn if a deprecated or unavailable declaration is being 241/// used, or produce an error (and return true) if a C++0x deleted 242/// function is being used. 243/// 244/// \returns true if there was an error (this declaration cannot be 245/// referenced), false otherwise. 246/// 247bool Sema::DiagnoseUseOfDecl(NamedDecl *D, SourceLocation Loc, 248 const ObjCInterfaceDecl *UnknownObjCClass) { 249 if (getLangOpts().CPlusPlus && isa<FunctionDecl>(D)) { 250 // If there were any diagnostics suppressed by template argument deduction, 251 // emit them now. 252 llvm::DenseMap<Decl *, SmallVector<PartialDiagnosticAt, 1> >::iterator 253 Pos = SuppressedDiagnostics.find(D->getCanonicalDecl()); 254 if (Pos != SuppressedDiagnostics.end()) { 255 SmallVectorImpl<PartialDiagnosticAt> &Suppressed = Pos->second; 256 for (unsigned I = 0, N = Suppressed.size(); I != N; ++I) 257 Diag(Suppressed[I].first, Suppressed[I].second); 258 259 // Clear out the list of suppressed diagnostics, so that we don't emit 260 // them again for this specialization. However, we don't obsolete this 261 // entry from the table, because we want to avoid ever emitting these 262 // diagnostics again. 263 Suppressed.clear(); 264 } 265 } 266 267 // See if this is an auto-typed variable whose initializer we are parsing. 268 if (ParsingInitForAutoVars.count(D)) { 269 Diag(Loc, diag::err_auto_variable_cannot_appear_in_own_initializer) 270 << D->getDeclName(); 271 return true; 272 } 273 274 // See if this is a deleted function. 275 if (FunctionDecl *FD = dyn_cast<FunctionDecl>(D)) { 276 if (FD->isDeleted()) { 277 Diag(Loc, diag::err_deleted_function_use); 278 NoteDeletedFunction(FD); 279 return true; 280 } 281 } 282 DiagnoseAvailabilityOfDecl(*this, D, Loc, UnknownObjCClass); 283 284 DiagnoseUnusedOfDecl(*this, D, Loc); 285 286 diagnoseUseOfInternalDeclInInlineFunction(*this, D, Loc); 287 288 return false; 289} 290 291/// \brief Retrieve the message suffix that should be added to a 292/// diagnostic complaining about the given function being deleted or 293/// unavailable. 294std::string Sema::getDeletedOrUnavailableSuffix(const FunctionDecl *FD) { 295 std::string Message; 296 if (FD->getAvailability(&Message)) 297 return ": " + Message; 298 299 return std::string(); 300} 301 302/// DiagnoseSentinelCalls - This routine checks whether a call or 303/// message-send is to a declaration with the sentinel attribute, and 304/// if so, it checks that the requirements of the sentinel are 305/// satisfied. 306void Sema::DiagnoseSentinelCalls(NamedDecl *D, SourceLocation Loc, 307 Expr **args, unsigned numArgs) { 308 const SentinelAttr *attr = D->getAttr<SentinelAttr>(); 309 if (!attr) 310 return; 311 312 // The number of formal parameters of the declaration. 313 unsigned numFormalParams; 314 315 // The kind of declaration. This is also an index into a %select in 316 // the diagnostic. 317 enum CalleeType { CT_Function, CT_Method, CT_Block } calleeType; 318 319 if (ObjCMethodDecl *MD = dyn_cast<ObjCMethodDecl>(D)) { 320 numFormalParams = MD->param_size(); 321 calleeType = CT_Method; 322 } else if (FunctionDecl *FD = dyn_cast<FunctionDecl>(D)) { 323 numFormalParams = FD->param_size(); 324 calleeType = CT_Function; 325 } else if (isa<VarDecl>(D)) { 326 QualType type = cast<ValueDecl>(D)->getType(); 327 const FunctionType *fn = 0; 328 if (const PointerType *ptr = type->getAs<PointerType>()) { 329 fn = ptr->getPointeeType()->getAs<FunctionType>(); 330 if (!fn) return; 331 calleeType = CT_Function; 332 } else if (const BlockPointerType *ptr = type->getAs<BlockPointerType>()) { 333 fn = ptr->getPointeeType()->castAs<FunctionType>(); 334 calleeType = CT_Block; 335 } else { 336 return; 337 } 338 339 if (const FunctionProtoType *proto = dyn_cast<FunctionProtoType>(fn)) { 340 numFormalParams = proto->getNumArgs(); 341 } else { 342 numFormalParams = 0; 343 } 344 } else { 345 return; 346 } 347 348 // "nullPos" is the number of formal parameters at the end which 349 // effectively count as part of the variadic arguments. This is 350 // useful if you would prefer to not have *any* formal parameters, 351 // but the language forces you to have at least one. 352 unsigned nullPos = attr->getNullPos(); 353 assert((nullPos == 0 || nullPos == 1) && "invalid null position on sentinel"); 354 numFormalParams = (nullPos > numFormalParams ? 0 : numFormalParams - nullPos); 355 356 // The number of arguments which should follow the sentinel. 357 unsigned numArgsAfterSentinel = attr->getSentinel(); 358 359 // If there aren't enough arguments for all the formal parameters, 360 // the sentinel, and the args after the sentinel, complain. 361 if (numArgs < numFormalParams + numArgsAfterSentinel + 1) { 362 Diag(Loc, diag::warn_not_enough_argument) << D->getDeclName(); 363 Diag(D->getLocation(), diag::note_sentinel_here) << calleeType; 364 return; 365 } 366 367 // Otherwise, find the sentinel expression. 368 Expr *sentinelExpr = args[numArgs - numArgsAfterSentinel - 1]; 369 if (!sentinelExpr) return; 370 if (sentinelExpr->isValueDependent()) return; 371 if (Context.isSentinelNullExpr(sentinelExpr)) return; 372 373 // Pick a reasonable string to insert. Optimistically use 'nil' or 374 // 'NULL' if those are actually defined in the context. Only use 375 // 'nil' for ObjC methods, where it's much more likely that the 376 // variadic arguments form a list of object pointers. 377 SourceLocation MissingNilLoc 378 = PP.getLocForEndOfToken(sentinelExpr->getLocEnd()); 379 std::string NullValue; 380 if (calleeType == CT_Method && 381 PP.getIdentifierInfo("nil")->hasMacroDefinition()) 382 NullValue = "nil"; 383 else if (PP.getIdentifierInfo("NULL")->hasMacroDefinition()) 384 NullValue = "NULL"; 385 else 386 NullValue = "(void*) 0"; 387 388 if (MissingNilLoc.isInvalid()) 389 Diag(Loc, diag::warn_missing_sentinel) << calleeType; 390 else 391 Diag(MissingNilLoc, diag::warn_missing_sentinel) 392 << calleeType 393 << FixItHint::CreateInsertion(MissingNilLoc, ", " + NullValue); 394 Diag(D->getLocation(), diag::note_sentinel_here) << calleeType; 395} 396 397SourceRange Sema::getExprRange(Expr *E) const { 398 return E ? E->getSourceRange() : SourceRange(); 399} 400 401//===----------------------------------------------------------------------===// 402// Standard Promotions and Conversions 403//===----------------------------------------------------------------------===// 404 405/// DefaultFunctionArrayConversion (C99 6.3.2.1p3, C99 6.3.2.1p4). 406ExprResult Sema::DefaultFunctionArrayConversion(Expr *E) { 407 // Handle any placeholder expressions which made it here. 408 if (E->getType()->isPlaceholderType()) { 409 ExprResult result = CheckPlaceholderExpr(E); 410 if (result.isInvalid()) return ExprError(); 411 E = result.take(); 412 } 413 414 QualType Ty = E->getType(); 415 assert(!Ty.isNull() && "DefaultFunctionArrayConversion - missing type"); 416 417 if (Ty->isFunctionType()) 418 E = ImpCastExprToType(E, Context.getPointerType(Ty), 419 CK_FunctionToPointerDecay).take(); 420 else if (Ty->isArrayType()) { 421 // In C90 mode, arrays only promote to pointers if the array expression is 422 // an lvalue. The relevant legalese is C90 6.2.2.1p3: "an lvalue that has 423 // type 'array of type' is converted to an expression that has type 'pointer 424 // to type'...". In C99 this was changed to: C99 6.3.2.1p3: "an expression 425 // that has type 'array of type' ...". The relevant change is "an lvalue" 426 // (C90) to "an expression" (C99). 427 // 428 // C++ 4.2p1: 429 // An lvalue or rvalue of type "array of N T" or "array of unknown bound of 430 // T" can be converted to an rvalue of type "pointer to T". 431 // 432 if (getLangOpts().C99 || getLangOpts().CPlusPlus || E->isLValue()) 433 E = ImpCastExprToType(E, Context.getArrayDecayedType(Ty), 434 CK_ArrayToPointerDecay).take(); 435 } 436 return Owned(E); 437} 438 439static void CheckForNullPointerDereference(Sema &S, Expr *E) { 440 // Check to see if we are dereferencing a null pointer. If so, 441 // and if not volatile-qualified, this is undefined behavior that the 442 // optimizer will delete, so warn about it. People sometimes try to use this 443 // to get a deterministic trap and are surprised by clang's behavior. This 444 // only handles the pattern "*null", which is a very syntactic check. 445 if (UnaryOperator *UO = dyn_cast<UnaryOperator>(E->IgnoreParenCasts())) 446 if (UO->getOpcode() == UO_Deref && 447 UO->getSubExpr()->IgnoreParenCasts()-> 448 isNullPointerConstant(S.Context, Expr::NPC_ValueDependentIsNotNull) && 449 !UO->getType().isVolatileQualified()) { 450 S.DiagRuntimeBehavior(UO->getOperatorLoc(), UO, 451 S.PDiag(diag::warn_indirection_through_null) 452 << UO->getSubExpr()->getSourceRange()); 453 S.DiagRuntimeBehavior(UO->getOperatorLoc(), UO, 454 S.PDiag(diag::note_indirection_through_null)); 455 } 456} 457 458static void DiagnoseDirectIsaAccess(Sema &S, const ObjCIvarRefExpr *OIRE, 459 SourceLocation AssignLoc, 460 const Expr* RHS) { 461 const ObjCIvarDecl *IV = OIRE->getDecl(); 462 if (!IV) 463 return; 464 465 DeclarationName MemberName = IV->getDeclName(); 466 IdentifierInfo *Member = MemberName.getAsIdentifierInfo(); 467 if (!Member || !Member->isStr("isa")) 468 return; 469 470 const Expr *Base = OIRE->getBase(); 471 QualType BaseType = Base->getType(); 472 if (OIRE->isArrow()) 473 BaseType = BaseType->getPointeeType(); 474 if (const ObjCObjectType *OTy = BaseType->getAs<ObjCObjectType>()) 475 if (ObjCInterfaceDecl *IDecl = OTy->getInterface()) { 476 ObjCInterfaceDecl *ClassDeclared = 0; 477 ObjCIvarDecl *IV = IDecl->lookupInstanceVariable(Member, ClassDeclared); 478 if (!ClassDeclared->getSuperClass() 479 && (*ClassDeclared->ivar_begin()) == IV) { 480 if (RHS) { 481 NamedDecl *ObjectSetClass = 482 S.LookupSingleName(S.TUScope, 483 &S.Context.Idents.get("object_setClass"), 484 SourceLocation(), S.LookupOrdinaryName); 485 if (ObjectSetClass) { 486 SourceLocation RHSLocEnd = S.PP.getLocForEndOfToken(RHS->getLocEnd()); 487 S.Diag(OIRE->getExprLoc(), diag::warn_objc_isa_assign) << 488 FixItHint::CreateInsertion(OIRE->getLocStart(), "object_setClass(") << 489 FixItHint::CreateReplacement(SourceRange(OIRE->getOpLoc(), 490 AssignLoc), ",") << 491 FixItHint::CreateInsertion(RHSLocEnd, ")"); 492 } 493 else 494 S.Diag(OIRE->getLocation(), diag::warn_objc_isa_assign); 495 } else { 496 NamedDecl *ObjectGetClass = 497 S.LookupSingleName(S.TUScope, 498 &S.Context.Idents.get("object_getClass"), 499 SourceLocation(), S.LookupOrdinaryName); 500 if (ObjectGetClass) 501 S.Diag(OIRE->getExprLoc(), diag::warn_objc_isa_use) << 502 FixItHint::CreateInsertion(OIRE->getLocStart(), "object_getClass(") << 503 FixItHint::CreateReplacement( 504 SourceRange(OIRE->getOpLoc(), 505 OIRE->getLocEnd()), ")"); 506 else 507 S.Diag(OIRE->getLocation(), diag::warn_objc_isa_use); 508 } 509 S.Diag(IV->getLocation(), diag::note_ivar_decl); 510 } 511 } 512} 513 514ExprResult Sema::DefaultLvalueConversion(Expr *E) { 515 // Handle any placeholder expressions which made it here. 516 if (E->getType()->isPlaceholderType()) { 517 ExprResult result = CheckPlaceholderExpr(E); 518 if (result.isInvalid()) return ExprError(); 519 E = result.take(); 520 } 521 522 // C++ [conv.lval]p1: 523 // A glvalue of a non-function, non-array type T can be 524 // converted to a prvalue. 525 if (!E->isGLValue()) return Owned(E); 526 527 QualType T = E->getType(); 528 assert(!T.isNull() && "r-value conversion on typeless expression?"); 529 530 // We don't want to throw lvalue-to-rvalue casts on top of 531 // expressions of certain types in C++. 532 if (getLangOpts().CPlusPlus && 533 (E->getType() == Context.OverloadTy || 534 T->isDependentType() || 535 T->isRecordType())) 536 return Owned(E); 537 538 // The C standard is actually really unclear on this point, and 539 // DR106 tells us what the result should be but not why. It's 540 // generally best to say that void types just doesn't undergo 541 // lvalue-to-rvalue at all. Note that expressions of unqualified 542 // 'void' type are never l-values, but qualified void can be. 543 if (T->isVoidType()) 544 return Owned(E); 545 546 // OpenCL usually rejects direct accesses to values of 'half' type. 547 if (getLangOpts().OpenCL && !getOpenCLOptions().cl_khr_fp16 && 548 T->isHalfType()) { 549 Diag(E->getExprLoc(), diag::err_opencl_half_load_store) 550 << 0 << T; 551 return ExprError(); 552 } 553 554 CheckForNullPointerDereference(*this, E); 555 if (const ObjCIsaExpr *OISA = dyn_cast<ObjCIsaExpr>(E->IgnoreParenCasts())) { 556 NamedDecl *ObjectGetClass = LookupSingleName(TUScope, 557 &Context.Idents.get("object_getClass"), 558 SourceLocation(), LookupOrdinaryName); 559 if (ObjectGetClass) 560 Diag(E->getExprLoc(), diag::warn_objc_isa_use) << 561 FixItHint::CreateInsertion(OISA->getLocStart(), "object_getClass(") << 562 FixItHint::CreateReplacement( 563 SourceRange(OISA->getOpLoc(), OISA->getIsaMemberLoc()), ")"); 564 else 565 Diag(E->getExprLoc(), diag::warn_objc_isa_use); 566 } 567 else if (const ObjCIvarRefExpr *OIRE = 568 dyn_cast<ObjCIvarRefExpr>(E->IgnoreParenCasts())) 569 DiagnoseDirectIsaAccess(*this, OIRE, SourceLocation(), /* Expr*/0); 570 571 // C++ [conv.lval]p1: 572 // [...] If T is a non-class type, the type of the prvalue is the 573 // cv-unqualified version of T. Otherwise, the type of the 574 // rvalue is T. 575 // 576 // C99 6.3.2.1p2: 577 // If the lvalue has qualified type, the value has the unqualified 578 // version of the type of the lvalue; otherwise, the value has the 579 // type of the lvalue. 580 if (T.hasQualifiers()) 581 T = T.getUnqualifiedType(); 582 583 UpdateMarkingForLValueToRValue(E); 584 585 // Loading a __weak object implicitly retains the value, so we need a cleanup to 586 // balance that. 587 if (getLangOpts().ObjCAutoRefCount && 588 E->getType().getObjCLifetime() == Qualifiers::OCL_Weak) 589 ExprNeedsCleanups = true; 590 591 ExprResult Res = Owned(ImplicitCastExpr::Create(Context, T, CK_LValueToRValue, 592 E, 0, VK_RValue)); 593 594 // C11 6.3.2.1p2: 595 // ... if the lvalue has atomic type, the value has the non-atomic version 596 // of the type of the lvalue ... 597 if (const AtomicType *Atomic = T->getAs<AtomicType>()) { 598 T = Atomic->getValueType().getUnqualifiedType(); 599 Res = Owned(ImplicitCastExpr::Create(Context, T, CK_AtomicToNonAtomic, 600 Res.get(), 0, VK_RValue)); 601 } 602 603 return Res; 604} 605 606ExprResult Sema::DefaultFunctionArrayLvalueConversion(Expr *E) { 607 ExprResult Res = DefaultFunctionArrayConversion(E); 608 if (Res.isInvalid()) 609 return ExprError(); 610 Res = DefaultLvalueConversion(Res.take()); 611 if (Res.isInvalid()) 612 return ExprError(); 613 return Res; 614} 615 616 617/// UsualUnaryConversions - Performs various conversions that are common to most 618/// operators (C99 6.3). The conversions of array and function types are 619/// sometimes suppressed. For example, the array->pointer conversion doesn't 620/// apply if the array is an argument to the sizeof or address (&) operators. 621/// In these instances, this routine should *not* be called. 622ExprResult Sema::UsualUnaryConversions(Expr *E) { 623 // First, convert to an r-value. 624 ExprResult Res = DefaultFunctionArrayLvalueConversion(E); 625 if (Res.isInvalid()) 626 return ExprError(); 627 E = Res.take(); 628 629 QualType Ty = E->getType(); 630 assert(!Ty.isNull() && "UsualUnaryConversions - missing type"); 631 632 // Half FP have to be promoted to float unless it is natively supported 633 if (Ty->isHalfType() && !getLangOpts().NativeHalfType) 634 return ImpCastExprToType(Res.take(), Context.FloatTy, CK_FloatingCast); 635 636 // Try to perform integral promotions if the object has a theoretically 637 // promotable type. 638 if (Ty->isIntegralOrUnscopedEnumerationType()) { 639 // C99 6.3.1.1p2: 640 // 641 // The following may be used in an expression wherever an int or 642 // unsigned int may be used: 643 // - an object or expression with an integer type whose integer 644 // conversion rank is less than or equal to the rank of int 645 // and unsigned int. 646 // - A bit-field of type _Bool, int, signed int, or unsigned int. 647 // 648 // If an int can represent all values of the original type, the 649 // value is converted to an int; otherwise, it is converted to an 650 // unsigned int. These are called the integer promotions. All 651 // other types are unchanged by the integer promotions. 652 653 QualType PTy = Context.isPromotableBitField(E); 654 if (!PTy.isNull()) { 655 E = ImpCastExprToType(E, PTy, CK_IntegralCast).take(); 656 return Owned(E); 657 } 658 if (Ty->isPromotableIntegerType()) { 659 QualType PT = Context.getPromotedIntegerType(Ty); 660 E = ImpCastExprToType(E, PT, CK_IntegralCast).take(); 661 return Owned(E); 662 } 663 } 664 return Owned(E); 665} 666 667/// DefaultArgumentPromotion (C99 6.5.2.2p6). Used for function calls that 668/// do not have a prototype. Arguments that have type float or __fp16 669/// are promoted to double. All other argument types are converted by 670/// UsualUnaryConversions(). 671ExprResult Sema::DefaultArgumentPromotion(Expr *E) { 672 QualType Ty = E->getType(); 673 assert(!Ty.isNull() && "DefaultArgumentPromotion - missing type"); 674 675 ExprResult Res = UsualUnaryConversions(E); 676 if (Res.isInvalid()) 677 return ExprError(); 678 E = Res.take(); 679 680 // If this is a 'float' or '__fp16' (CVR qualified or typedef) promote to 681 // double. 682 const BuiltinType *BTy = Ty->getAs<BuiltinType>(); 683 if (BTy && (BTy->getKind() == BuiltinType::Half || 684 BTy->getKind() == BuiltinType::Float)) 685 E = ImpCastExprToType(E, Context.DoubleTy, CK_FloatingCast).take(); 686 687 // C++ performs lvalue-to-rvalue conversion as a default argument 688 // promotion, even on class types, but note: 689 // C++11 [conv.lval]p2: 690 // When an lvalue-to-rvalue conversion occurs in an unevaluated 691 // operand or a subexpression thereof the value contained in the 692 // referenced object is not accessed. Otherwise, if the glvalue 693 // has a class type, the conversion copy-initializes a temporary 694 // of type T from the glvalue and the result of the conversion 695 // is a prvalue for the temporary. 696 // FIXME: add some way to gate this entire thing for correctness in 697 // potentially potentially evaluated contexts. 698 if (getLangOpts().CPlusPlus && E->isGLValue() && !isUnevaluatedContext()) { 699 ExprResult Temp = PerformCopyInitialization( 700 InitializedEntity::InitializeTemporary(E->getType()), 701 E->getExprLoc(), 702 Owned(E)); 703 if (Temp.isInvalid()) 704 return ExprError(); 705 E = Temp.get(); 706 } 707 708 return Owned(E); 709} 710 711/// Determine the degree of POD-ness for an expression. 712/// Incomplete types are considered POD, since this check can be performed 713/// when we're in an unevaluated context. 714Sema::VarArgKind Sema::isValidVarArgType(const QualType &Ty) { 715 if (Ty->isIncompleteType()) { 716 if (Ty->isObjCObjectType()) 717 return VAK_Invalid; 718 return VAK_Valid; 719 } 720 721 if (Ty.isCXX98PODType(Context)) 722 return VAK_Valid; 723 724 // C++11 [expr.call]p7: 725 // Passing a potentially-evaluated argument of class type (Clause 9) 726 // having a non-trivial copy constructor, a non-trivial move constructor, 727 // or a non-trivial destructor, with no corresponding parameter, 728 // is conditionally-supported with implementation-defined semantics. 729 if (getLangOpts().CPlusPlus11 && !Ty->isDependentType()) 730 if (CXXRecordDecl *Record = Ty->getAsCXXRecordDecl()) 731 if (!Record->hasNonTrivialCopyConstructor() && 732 !Record->hasNonTrivialMoveConstructor() && 733 !Record->hasNonTrivialDestructor()) 734 return VAK_ValidInCXX11; 735 736 if (getLangOpts().ObjCAutoRefCount && Ty->isObjCLifetimeType()) 737 return VAK_Valid; 738 return VAK_Invalid; 739} 740 741bool Sema::variadicArgumentPODCheck(const Expr *E, VariadicCallType CT) { 742 // Don't allow one to pass an Objective-C interface to a vararg. 743 const QualType & Ty = E->getType(); 744 745 // Complain about passing non-POD types through varargs. 746 switch (isValidVarArgType(Ty)) { 747 case VAK_Valid: 748 break; 749 case VAK_ValidInCXX11: 750 DiagRuntimeBehavior(E->getLocStart(), 0, 751 PDiag(diag::warn_cxx98_compat_pass_non_pod_arg_to_vararg) 752 << E->getType() << CT); 753 break; 754 case VAK_Invalid: { 755 if (Ty->isObjCObjectType()) 756 return DiagRuntimeBehavior(E->getLocStart(), 0, 757 PDiag(diag::err_cannot_pass_objc_interface_to_vararg) 758 << Ty << CT); 759 760 return DiagRuntimeBehavior(E->getLocStart(), 0, 761 PDiag(diag::warn_cannot_pass_non_pod_arg_to_vararg) 762 << getLangOpts().CPlusPlus11 << Ty << CT); 763 } 764 } 765 // c++ rules are enforced elsewhere. 766 return false; 767} 768 769/// DefaultVariadicArgumentPromotion - Like DefaultArgumentPromotion, but 770/// will create a trap if the resulting type is not a POD type. 771ExprResult Sema::DefaultVariadicArgumentPromotion(Expr *E, VariadicCallType CT, 772 FunctionDecl *FDecl) { 773 if (const BuiltinType *PlaceholderTy = E->getType()->getAsPlaceholderType()) { 774 // Strip the unbridged-cast placeholder expression off, if applicable. 775 if (PlaceholderTy->getKind() == BuiltinType::ARCUnbridgedCast && 776 (CT == VariadicMethod || 777 (FDecl && FDecl->hasAttr<CFAuditedTransferAttr>()))) { 778 E = stripARCUnbridgedCast(E); 779 780 // Otherwise, do normal placeholder checking. 781 } else { 782 ExprResult ExprRes = CheckPlaceholderExpr(E); 783 if (ExprRes.isInvalid()) 784 return ExprError(); 785 E = ExprRes.take(); 786 } 787 } 788 789 ExprResult ExprRes = DefaultArgumentPromotion(E); 790 if (ExprRes.isInvalid()) 791 return ExprError(); 792 E = ExprRes.take(); 793 794 // Diagnostics regarding non-POD argument types are 795 // emitted along with format string checking in Sema::CheckFunctionCall(). 796 if (isValidVarArgType(E->getType()) == VAK_Invalid) { 797 // Turn this into a trap. 798 CXXScopeSpec SS; 799 SourceLocation TemplateKWLoc; 800 UnqualifiedId Name; 801 Name.setIdentifier(PP.getIdentifierInfo("__builtin_trap"), 802 E->getLocStart()); 803 ExprResult TrapFn = ActOnIdExpression(TUScope, SS, TemplateKWLoc, 804 Name, true, false); 805 if (TrapFn.isInvalid()) 806 return ExprError(); 807 808 ExprResult Call = ActOnCallExpr(TUScope, TrapFn.get(), 809 E->getLocStart(), MultiExprArg(), 810 E->getLocEnd()); 811 if (Call.isInvalid()) 812 return ExprError(); 813 814 ExprResult Comma = ActOnBinOp(TUScope, E->getLocStart(), tok::comma, 815 Call.get(), E); 816 if (Comma.isInvalid()) 817 return ExprError(); 818 return Comma.get(); 819 } 820 821 if (!getLangOpts().CPlusPlus && 822 RequireCompleteType(E->getExprLoc(), E->getType(), 823 diag::err_call_incomplete_argument)) 824 return ExprError(); 825 826 return Owned(E); 827} 828 829/// \brief Converts an integer to complex float type. Helper function of 830/// UsualArithmeticConversions() 831/// 832/// \return false if the integer expression is an integer type and is 833/// successfully converted to the complex type. 834static bool handleIntegerToComplexFloatConversion(Sema &S, ExprResult &IntExpr, 835 ExprResult &ComplexExpr, 836 QualType IntTy, 837 QualType ComplexTy, 838 bool SkipCast) { 839 if (IntTy->isComplexType() || IntTy->isRealFloatingType()) return true; 840 if (SkipCast) return false; 841 if (IntTy->isIntegerType()) { 842 QualType fpTy = cast<ComplexType>(ComplexTy)->getElementType(); 843 IntExpr = S.ImpCastExprToType(IntExpr.take(), fpTy, CK_IntegralToFloating); 844 IntExpr = S.ImpCastExprToType(IntExpr.take(), ComplexTy, 845 CK_FloatingRealToComplex); 846 } else { 847 assert(IntTy->isComplexIntegerType()); 848 IntExpr = S.ImpCastExprToType(IntExpr.take(), ComplexTy, 849 CK_IntegralComplexToFloatingComplex); 850 } 851 return false; 852} 853 854/// \brief Takes two complex float types and converts them to the same type. 855/// Helper function of UsualArithmeticConversions() 856static QualType 857handleComplexFloatToComplexFloatConverstion(Sema &S, ExprResult &LHS, 858 ExprResult &RHS, QualType LHSType, 859 QualType RHSType, 860 bool IsCompAssign) { 861 int order = S.Context.getFloatingTypeOrder(LHSType, RHSType); 862 863 if (order < 0) { 864 // _Complex float -> _Complex double 865 if (!IsCompAssign) 866 LHS = S.ImpCastExprToType(LHS.take(), RHSType, CK_FloatingComplexCast); 867 return RHSType; 868 } 869 if (order > 0) 870 // _Complex float -> _Complex double 871 RHS = S.ImpCastExprToType(RHS.take(), LHSType, CK_FloatingComplexCast); 872 return LHSType; 873} 874 875/// \brief Converts otherExpr to complex float and promotes complexExpr if 876/// necessary. Helper function of UsualArithmeticConversions() 877static QualType handleOtherComplexFloatConversion(Sema &S, 878 ExprResult &ComplexExpr, 879 ExprResult &OtherExpr, 880 QualType ComplexTy, 881 QualType OtherTy, 882 bool ConvertComplexExpr, 883 bool ConvertOtherExpr) { 884 int order = S.Context.getFloatingTypeOrder(ComplexTy, OtherTy); 885 886 // If just the complexExpr is complex, the otherExpr needs to be converted, 887 // and the complexExpr might need to be promoted. 888 if (order > 0) { // complexExpr is wider 889 // float -> _Complex double 890 if (ConvertOtherExpr) { 891 QualType fp = cast<ComplexType>(ComplexTy)->getElementType(); 892 OtherExpr = S.ImpCastExprToType(OtherExpr.take(), fp, CK_FloatingCast); 893 OtherExpr = S.ImpCastExprToType(OtherExpr.take(), ComplexTy, 894 CK_FloatingRealToComplex); 895 } 896 return ComplexTy; 897 } 898 899 // otherTy is at least as wide. Find its corresponding complex type. 900 QualType result = (order == 0 ? ComplexTy : 901 S.Context.getComplexType(OtherTy)); 902 903 // double -> _Complex double 904 if (ConvertOtherExpr) 905 OtherExpr = S.ImpCastExprToType(OtherExpr.take(), result, 906 CK_FloatingRealToComplex); 907 908 // _Complex float -> _Complex double 909 if (ConvertComplexExpr && order < 0) 910 ComplexExpr = S.ImpCastExprToType(ComplexExpr.take(), result, 911 CK_FloatingComplexCast); 912 913 return result; 914} 915 916/// \brief Handle arithmetic conversion with complex types. Helper function of 917/// UsualArithmeticConversions() 918static QualType handleComplexFloatConversion(Sema &S, ExprResult &LHS, 919 ExprResult &RHS, QualType LHSType, 920 QualType RHSType, 921 bool IsCompAssign) { 922 // if we have an integer operand, the result is the complex type. 923 if (!handleIntegerToComplexFloatConversion(S, RHS, LHS, RHSType, LHSType, 924 /*skipCast*/false)) 925 return LHSType; 926 if (!handleIntegerToComplexFloatConversion(S, LHS, RHS, LHSType, RHSType, 927 /*skipCast*/IsCompAssign)) 928 return RHSType; 929 930 // This handles complex/complex, complex/float, or float/complex. 931 // When both operands are complex, the shorter operand is converted to the 932 // type of the longer, and that is the type of the result. This corresponds 933 // to what is done when combining two real floating-point operands. 934 // The fun begins when size promotion occur across type domains. 935 // From H&S 6.3.4: When one operand is complex and the other is a real 936 // floating-point type, the less precise type is converted, within it's 937 // real or complex domain, to the precision of the other type. For example, 938 // when combining a "long double" with a "double _Complex", the 939 // "double _Complex" is promoted to "long double _Complex". 940 941 bool LHSComplexFloat = LHSType->isComplexType(); 942 bool RHSComplexFloat = RHSType->isComplexType(); 943 944 // If both are complex, just cast to the more precise type. 945 if (LHSComplexFloat && RHSComplexFloat) 946 return handleComplexFloatToComplexFloatConverstion(S, LHS, RHS, 947 LHSType, RHSType, 948 IsCompAssign); 949 950 // If only one operand is complex, promote it if necessary and convert the 951 // other operand to complex. 952 if (LHSComplexFloat) 953 return handleOtherComplexFloatConversion( 954 S, LHS, RHS, LHSType, RHSType, /*convertComplexExpr*/!IsCompAssign, 955 /*convertOtherExpr*/ true); 956 957 assert(RHSComplexFloat); 958 return handleOtherComplexFloatConversion( 959 S, RHS, LHS, RHSType, LHSType, /*convertComplexExpr*/true, 960 /*convertOtherExpr*/ !IsCompAssign); 961} 962 963/// \brief Hande arithmetic conversion from integer to float. Helper function 964/// of UsualArithmeticConversions() 965static QualType handleIntToFloatConversion(Sema &S, ExprResult &FloatExpr, 966 ExprResult &IntExpr, 967 QualType FloatTy, QualType IntTy, 968 bool ConvertFloat, bool ConvertInt) { 969 if (IntTy->isIntegerType()) { 970 if (ConvertInt) 971 // Convert intExpr to the lhs floating point type. 972 IntExpr = S.ImpCastExprToType(IntExpr.take(), FloatTy, 973 CK_IntegralToFloating); 974 return FloatTy; 975 } 976 977 // Convert both sides to the appropriate complex float. 978 assert(IntTy->isComplexIntegerType()); 979 QualType result = S.Context.getComplexType(FloatTy); 980 981 // _Complex int -> _Complex float 982 if (ConvertInt) 983 IntExpr = S.ImpCastExprToType(IntExpr.take(), result, 984 CK_IntegralComplexToFloatingComplex); 985 986 // float -> _Complex float 987 if (ConvertFloat) 988 FloatExpr = S.ImpCastExprToType(FloatExpr.take(), result, 989 CK_FloatingRealToComplex); 990 991 return result; 992} 993 994/// \brief Handle arithmethic conversion with floating point types. Helper 995/// function of UsualArithmeticConversions() 996static QualType handleFloatConversion(Sema &S, ExprResult &LHS, 997 ExprResult &RHS, QualType LHSType, 998 QualType RHSType, bool IsCompAssign) { 999 bool LHSFloat = LHSType->isRealFloatingType(); 1000 bool RHSFloat = RHSType->isRealFloatingType(); 1001 1002 // If we have two real floating types, convert the smaller operand 1003 // to the bigger result. 1004 if (LHSFloat && RHSFloat) { 1005 int order = S.Context.getFloatingTypeOrder(LHSType, RHSType); 1006 if (order > 0) { 1007 RHS = S.ImpCastExprToType(RHS.take(), LHSType, CK_FloatingCast); 1008 return LHSType; 1009 } 1010 1011 assert(order < 0 && "illegal float comparison"); 1012 if (!IsCompAssign) 1013 LHS = S.ImpCastExprToType(LHS.take(), RHSType, CK_FloatingCast); 1014 return RHSType; 1015 } 1016 1017 if (LHSFloat) 1018 return handleIntToFloatConversion(S, LHS, RHS, LHSType, RHSType, 1019 /*convertFloat=*/!IsCompAssign, 1020 /*convertInt=*/ true); 1021 assert(RHSFloat); 1022 return handleIntToFloatConversion(S, RHS, LHS, RHSType, LHSType, 1023 /*convertInt=*/ true, 1024 /*convertFloat=*/!IsCompAssign); 1025} 1026 1027typedef ExprResult PerformCastFn(Sema &S, Expr *operand, QualType toType); 1028 1029namespace { 1030/// These helper callbacks are placed in an anonymous namespace to 1031/// permit their use as function template parameters. 1032ExprResult doIntegralCast(Sema &S, Expr *op, QualType toType) { 1033 return S.ImpCastExprToType(op, toType, CK_IntegralCast); 1034} 1035 1036ExprResult doComplexIntegralCast(Sema &S, Expr *op, QualType toType) { 1037 return S.ImpCastExprToType(op, S.Context.getComplexType(toType), 1038 CK_IntegralComplexCast); 1039} 1040} 1041 1042/// \brief Handle integer arithmetic conversions. Helper function of 1043/// UsualArithmeticConversions() 1044template <PerformCastFn doLHSCast, PerformCastFn doRHSCast> 1045static QualType handleIntegerConversion(Sema &S, ExprResult &LHS, 1046 ExprResult &RHS, QualType LHSType, 1047 QualType RHSType, bool IsCompAssign) { 1048 // The rules for this case are in C99 6.3.1.8 1049 int order = S.Context.getIntegerTypeOrder(LHSType, RHSType); 1050 bool LHSSigned = LHSType->hasSignedIntegerRepresentation(); 1051 bool RHSSigned = RHSType->hasSignedIntegerRepresentation(); 1052 if (LHSSigned == RHSSigned) { 1053 // Same signedness; use the higher-ranked type 1054 if (order >= 0) { 1055 RHS = (*doRHSCast)(S, RHS.take(), LHSType); 1056 return LHSType; 1057 } else if (!IsCompAssign) 1058 LHS = (*doLHSCast)(S, LHS.take(), RHSType); 1059 return RHSType; 1060 } else if (order != (LHSSigned ? 1 : -1)) { 1061 // The unsigned type has greater than or equal rank to the 1062 // signed type, so use the unsigned type 1063 if (RHSSigned) { 1064 RHS = (*doRHSCast)(S, RHS.take(), LHSType); 1065 return LHSType; 1066 } else if (!IsCompAssign) 1067 LHS = (*doLHSCast)(S, LHS.take(), RHSType); 1068 return RHSType; 1069 } else if (S.Context.getIntWidth(LHSType) != S.Context.getIntWidth(RHSType)) { 1070 // The two types are different widths; if we are here, that 1071 // means the signed type is larger than the unsigned type, so 1072 // use the signed type. 1073 if (LHSSigned) { 1074 RHS = (*doRHSCast)(S, RHS.take(), LHSType); 1075 return LHSType; 1076 } else if (!IsCompAssign) 1077 LHS = (*doLHSCast)(S, LHS.take(), RHSType); 1078 return RHSType; 1079 } else { 1080 // The signed type is higher-ranked than the unsigned type, 1081 // but isn't actually any bigger (like unsigned int and long 1082 // on most 32-bit systems). Use the unsigned type corresponding 1083 // to the signed type. 1084 QualType result = 1085 S.Context.getCorrespondingUnsignedType(LHSSigned ? LHSType : RHSType); 1086 RHS = (*doRHSCast)(S, RHS.take(), result); 1087 if (!IsCompAssign) 1088 LHS = (*doLHSCast)(S, LHS.take(), result); 1089 return result; 1090 } 1091} 1092 1093/// \brief Handle conversions with GCC complex int extension. Helper function 1094/// of UsualArithmeticConversions() 1095static QualType handleComplexIntConversion(Sema &S, ExprResult &LHS, 1096 ExprResult &RHS, QualType LHSType, 1097 QualType RHSType, 1098 bool IsCompAssign) { 1099 const ComplexType *LHSComplexInt = LHSType->getAsComplexIntegerType(); 1100 const ComplexType *RHSComplexInt = RHSType->getAsComplexIntegerType(); 1101 1102 if (LHSComplexInt && RHSComplexInt) { 1103 QualType LHSEltType = LHSComplexInt->getElementType(); 1104 QualType RHSEltType = RHSComplexInt->getElementType(); 1105 QualType ScalarType = 1106 handleIntegerConversion<doComplexIntegralCast, doComplexIntegralCast> 1107 (S, LHS, RHS, LHSEltType, RHSEltType, IsCompAssign); 1108 1109 return S.Context.getComplexType(ScalarType); 1110 } 1111 1112 if (LHSComplexInt) { 1113 QualType LHSEltType = LHSComplexInt->getElementType(); 1114 QualType ScalarType = 1115 handleIntegerConversion<doComplexIntegralCast, doIntegralCast> 1116 (S, LHS, RHS, LHSEltType, RHSType, IsCompAssign); 1117 QualType ComplexType = S.Context.getComplexType(ScalarType); 1118 RHS = S.ImpCastExprToType(RHS.take(), ComplexType, 1119 CK_IntegralRealToComplex); 1120 1121 return ComplexType; 1122 } 1123 1124 assert(RHSComplexInt); 1125 1126 QualType RHSEltType = RHSComplexInt->getElementType(); 1127 QualType ScalarType = 1128 handleIntegerConversion<doIntegralCast, doComplexIntegralCast> 1129 (S, LHS, RHS, LHSType, RHSEltType, IsCompAssign); 1130 QualType ComplexType = S.Context.getComplexType(ScalarType); 1131 1132 if (!IsCompAssign) 1133 LHS = S.ImpCastExprToType(LHS.take(), ComplexType, 1134 CK_IntegralRealToComplex); 1135 return ComplexType; 1136} 1137 1138/// UsualArithmeticConversions - Performs various conversions that are common to 1139/// binary operators (C99 6.3.1.8). If both operands aren't arithmetic, this 1140/// routine returns the first non-arithmetic type found. The client is 1141/// responsible for emitting appropriate error diagnostics. 1142QualType Sema::UsualArithmeticConversions(ExprResult &LHS, ExprResult &RHS, 1143 bool IsCompAssign) { 1144 if (!IsCompAssign) { 1145 LHS = UsualUnaryConversions(LHS.take()); 1146 if (LHS.isInvalid()) 1147 return QualType(); 1148 } 1149 1150 RHS = UsualUnaryConversions(RHS.take()); 1151 if (RHS.isInvalid()) 1152 return QualType(); 1153 1154 // For conversion purposes, we ignore any qualifiers. 1155 // For example, "const float" and "float" are equivalent. 1156 QualType LHSType = 1157 Context.getCanonicalType(LHS.get()->getType()).getUnqualifiedType(); 1158 QualType RHSType = 1159 Context.getCanonicalType(RHS.get()->getType()).getUnqualifiedType(); 1160 1161 // For conversion purposes, we ignore any atomic qualifier on the LHS. 1162 if (const AtomicType *AtomicLHS = LHSType->getAs<AtomicType>()) 1163 LHSType = AtomicLHS->getValueType(); 1164 1165 // If both types are identical, no conversion is needed. 1166 if (LHSType == RHSType) 1167 return LHSType; 1168 1169 // If either side is a non-arithmetic type (e.g. a pointer), we are done. 1170 // The caller can deal with this (e.g. pointer + int). 1171 if (!LHSType->isArithmeticType() || !RHSType->isArithmeticType()) 1172 return QualType(); 1173 1174 // Apply unary and bitfield promotions to the LHS's type. 1175 QualType LHSUnpromotedType = LHSType; 1176 if (LHSType->isPromotableIntegerType()) 1177 LHSType = Context.getPromotedIntegerType(LHSType); 1178 QualType LHSBitfieldPromoteTy = Context.isPromotableBitField(LHS.get()); 1179 if (!LHSBitfieldPromoteTy.isNull()) 1180 LHSType = LHSBitfieldPromoteTy; 1181 if (LHSType != LHSUnpromotedType && !IsCompAssign) 1182 LHS = ImpCastExprToType(LHS.take(), LHSType, CK_IntegralCast); 1183 1184 // If both types are identical, no conversion is needed. 1185 if (LHSType == RHSType) 1186 return LHSType; 1187 1188 // At this point, we have two different arithmetic types. 1189 1190 // Handle complex types first (C99 6.3.1.8p1). 1191 if (LHSType->isComplexType() || RHSType->isComplexType()) 1192 return handleComplexFloatConversion(*this, LHS, RHS, LHSType, RHSType, 1193 IsCompAssign); 1194 1195 // Now handle "real" floating types (i.e. float, double, long double). 1196 if (LHSType->isRealFloatingType() || RHSType->isRealFloatingType()) 1197 return handleFloatConversion(*this, LHS, RHS, LHSType, RHSType, 1198 IsCompAssign); 1199 1200 // Handle GCC complex int extension. 1201 if (LHSType->isComplexIntegerType() || RHSType->isComplexIntegerType()) 1202 return handleComplexIntConversion(*this, LHS, RHS, LHSType, RHSType, 1203 IsCompAssign); 1204 1205 // Finally, we have two differing integer types. 1206 return handleIntegerConversion<doIntegralCast, doIntegralCast> 1207 (*this, LHS, RHS, LHSType, RHSType, IsCompAssign); 1208} 1209 1210 1211//===----------------------------------------------------------------------===// 1212// Semantic Analysis for various Expression Types 1213//===----------------------------------------------------------------------===// 1214 1215 1216ExprResult 1217Sema::ActOnGenericSelectionExpr(SourceLocation KeyLoc, 1218 SourceLocation DefaultLoc, 1219 SourceLocation RParenLoc, 1220 Expr *ControllingExpr, 1221 MultiTypeArg ArgTypes, 1222 MultiExprArg ArgExprs) { 1223 unsigned NumAssocs = ArgTypes.size(); 1224 assert(NumAssocs == ArgExprs.size()); 1225 1226 ParsedType *ParsedTypes = ArgTypes.data(); 1227 Expr **Exprs = ArgExprs.data(); 1228 1229 TypeSourceInfo **Types = new TypeSourceInfo*[NumAssocs]; 1230 for (unsigned i = 0; i < NumAssocs; ++i) { 1231 if (ParsedTypes[i]) 1232 (void) GetTypeFromParser(ParsedTypes[i], &Types[i]); 1233 else 1234 Types[i] = 0; 1235 } 1236 1237 ExprResult ER = CreateGenericSelectionExpr(KeyLoc, DefaultLoc, RParenLoc, 1238 ControllingExpr, Types, Exprs, 1239 NumAssocs); 1240 delete [] Types; 1241 return ER; 1242} 1243 1244ExprResult 1245Sema::CreateGenericSelectionExpr(SourceLocation KeyLoc, 1246 SourceLocation DefaultLoc, 1247 SourceLocation RParenLoc, 1248 Expr *ControllingExpr, 1249 TypeSourceInfo **Types, 1250 Expr **Exprs, 1251 unsigned NumAssocs) { 1252 if (ControllingExpr->getType()->isPlaceholderType()) { 1253 ExprResult result = CheckPlaceholderExpr(ControllingExpr); 1254 if (result.isInvalid()) return ExprError(); 1255 ControllingExpr = result.take(); 1256 } 1257 1258 bool TypeErrorFound = false, 1259 IsResultDependent = ControllingExpr->isTypeDependent(), 1260 ContainsUnexpandedParameterPack 1261 = ControllingExpr->containsUnexpandedParameterPack(); 1262 1263 for (unsigned i = 0; i < NumAssocs; ++i) { 1264 if (Exprs[i]->containsUnexpandedParameterPack()) 1265 ContainsUnexpandedParameterPack = true; 1266 1267 if (Types[i]) { 1268 if (Types[i]->getType()->containsUnexpandedParameterPack()) 1269 ContainsUnexpandedParameterPack = true; 1270 1271 if (Types[i]->getType()->isDependentType()) { 1272 IsResultDependent = true; 1273 } else { 1274 // C11 6.5.1.1p2 "The type name in a generic association shall specify a 1275 // complete object type other than a variably modified type." 1276 unsigned D = 0; 1277 if (Types[i]->getType()->isIncompleteType()) 1278 D = diag::err_assoc_type_incomplete; 1279 else if (!Types[i]->getType()->isObjectType()) 1280 D = diag::err_assoc_type_nonobject; 1281 else if (Types[i]->getType()->isVariablyModifiedType()) 1282 D = diag::err_assoc_type_variably_modified; 1283 1284 if (D != 0) { 1285 Diag(Types[i]->getTypeLoc().getBeginLoc(), D) 1286 << Types[i]->getTypeLoc().getSourceRange() 1287 << Types[i]->getType(); 1288 TypeErrorFound = true; 1289 } 1290 1291 // C11 6.5.1.1p2 "No two generic associations in the same generic 1292 // selection shall specify compatible types." 1293 for (unsigned j = i+1; j < NumAssocs; ++j) 1294 if (Types[j] && !Types[j]->getType()->isDependentType() && 1295 Context.typesAreCompatible(Types[i]->getType(), 1296 Types[j]->getType())) { 1297 Diag(Types[j]->getTypeLoc().getBeginLoc(), 1298 diag::err_assoc_compatible_types) 1299 << Types[j]->getTypeLoc().getSourceRange() 1300 << Types[j]->getType() 1301 << Types[i]->getType(); 1302 Diag(Types[i]->getTypeLoc().getBeginLoc(), 1303 diag::note_compat_assoc) 1304 << Types[i]->getTypeLoc().getSourceRange() 1305 << Types[i]->getType(); 1306 TypeErrorFound = true; 1307 } 1308 } 1309 } 1310 } 1311 if (TypeErrorFound) 1312 return ExprError(); 1313 1314 // If we determined that the generic selection is result-dependent, don't 1315 // try to compute the result expression. 1316 if (IsResultDependent) 1317 return Owned(new (Context) GenericSelectionExpr( 1318 Context, KeyLoc, ControllingExpr, 1319 llvm::makeArrayRef(Types, NumAssocs), 1320 llvm::makeArrayRef(Exprs, NumAssocs), 1321 DefaultLoc, RParenLoc, ContainsUnexpandedParameterPack)); 1322 1323 SmallVector<unsigned, 1> CompatIndices; 1324 unsigned DefaultIndex = -1U; 1325 for (unsigned i = 0; i < NumAssocs; ++i) { 1326 if (!Types[i]) 1327 DefaultIndex = i; 1328 else if (Context.typesAreCompatible(ControllingExpr->getType(), 1329 Types[i]->getType())) 1330 CompatIndices.push_back(i); 1331 } 1332 1333 // C11 6.5.1.1p2 "The controlling expression of a generic selection shall have 1334 // type compatible with at most one of the types named in its generic 1335 // association list." 1336 if (CompatIndices.size() > 1) { 1337 // We strip parens here because the controlling expression is typically 1338 // parenthesized in macro definitions. 1339 ControllingExpr = ControllingExpr->IgnoreParens(); 1340 Diag(ControllingExpr->getLocStart(), diag::err_generic_sel_multi_match) 1341 << ControllingExpr->getSourceRange() << ControllingExpr->getType() 1342 << (unsigned) CompatIndices.size(); 1343 for (SmallVector<unsigned, 1>::iterator I = CompatIndices.begin(), 1344 E = CompatIndices.end(); I != E; ++I) { 1345 Diag(Types[*I]->getTypeLoc().getBeginLoc(), 1346 diag::note_compat_assoc) 1347 << Types[*I]->getTypeLoc().getSourceRange() 1348 << Types[*I]->getType(); 1349 } 1350 return ExprError(); 1351 } 1352 1353 // C11 6.5.1.1p2 "If a generic selection has no default generic association, 1354 // its controlling expression shall have type compatible with exactly one of 1355 // the types named in its generic association list." 1356 if (DefaultIndex == -1U && CompatIndices.size() == 0) { 1357 // We strip parens here because the controlling expression is typically 1358 // parenthesized in macro definitions. 1359 ControllingExpr = ControllingExpr->IgnoreParens(); 1360 Diag(ControllingExpr->getLocStart(), diag::err_generic_sel_no_match) 1361 << ControllingExpr->getSourceRange() << ControllingExpr->getType(); 1362 return ExprError(); 1363 } 1364 1365 // C11 6.5.1.1p3 "If a generic selection has a generic association with a 1366 // type name that is compatible with the type of the controlling expression, 1367 // then the result expression of the generic selection is the expression 1368 // in that generic association. Otherwise, the result expression of the 1369 // generic selection is the expression in the default generic association." 1370 unsigned ResultIndex = 1371 CompatIndices.size() ? CompatIndices[0] : DefaultIndex; 1372 1373 return Owned(new (Context) GenericSelectionExpr( 1374 Context, KeyLoc, ControllingExpr, 1375 llvm::makeArrayRef(Types, NumAssocs), 1376 llvm::makeArrayRef(Exprs, NumAssocs), 1377 DefaultLoc, RParenLoc, ContainsUnexpandedParameterPack, 1378 ResultIndex)); 1379} 1380 1381/// getUDSuffixLoc - Create a SourceLocation for a ud-suffix, given the 1382/// location of the token and the offset of the ud-suffix within it. 1383static SourceLocation getUDSuffixLoc(Sema &S, SourceLocation TokLoc, 1384 unsigned Offset) { 1385 return Lexer::AdvanceToTokenCharacter(TokLoc, Offset, S.getSourceManager(), 1386 S.getLangOpts()); 1387} 1388 1389/// BuildCookedLiteralOperatorCall - A user-defined literal was found. Look up 1390/// the corresponding cooked (non-raw) literal operator, and build a call to it. 1391static ExprResult BuildCookedLiteralOperatorCall(Sema &S, Scope *Scope, 1392 IdentifierInfo *UDSuffix, 1393 SourceLocation UDSuffixLoc, 1394 ArrayRef<Expr*> Args, 1395 SourceLocation LitEndLoc) { 1396 assert(Args.size() <= 2 && "too many arguments for literal operator"); 1397 1398 QualType ArgTy[2]; 1399 for (unsigned ArgIdx = 0; ArgIdx != Args.size(); ++ArgIdx) { 1400 ArgTy[ArgIdx] = Args[ArgIdx]->getType(); 1401 if (ArgTy[ArgIdx]->isArrayType()) 1402 ArgTy[ArgIdx] = S.Context.getArrayDecayedType(ArgTy[ArgIdx]); 1403 } 1404 1405 DeclarationName OpName = 1406 S.Context.DeclarationNames.getCXXLiteralOperatorName(UDSuffix); 1407 DeclarationNameInfo OpNameInfo(OpName, UDSuffixLoc); 1408 OpNameInfo.setCXXLiteralOperatorNameLoc(UDSuffixLoc); 1409 1410 LookupResult R(S, OpName, UDSuffixLoc, Sema::LookupOrdinaryName); 1411 if (S.LookupLiteralOperator(Scope, R, llvm::makeArrayRef(ArgTy, Args.size()), 1412 /*AllowRawAndTemplate*/false) == Sema::LOLR_Error) 1413 return ExprError(); 1414 1415 return S.BuildLiteralOperatorCall(R, OpNameInfo, Args, LitEndLoc); 1416} 1417 1418/// ActOnStringLiteral - The specified tokens were lexed as pasted string 1419/// fragments (e.g. "foo" "bar" L"baz"). The result string has to handle string 1420/// concatenation ([C99 5.1.1.2, translation phase #6]), so it may come from 1421/// multiple tokens. However, the common case is that StringToks points to one 1422/// string. 1423/// 1424ExprResult 1425Sema::ActOnStringLiteral(const Token *StringToks, unsigned NumStringToks, 1426 Scope *UDLScope) { 1427 assert(NumStringToks && "Must have at least one string!"); 1428 1429 StringLiteralParser Literal(StringToks, NumStringToks, PP); 1430 if (Literal.hadError) 1431 return ExprError(); 1432 1433 SmallVector<SourceLocation, 4> StringTokLocs; 1434 for (unsigned i = 0; i != NumStringToks; ++i) 1435 StringTokLocs.push_back(StringToks[i].getLocation()); 1436 1437 QualType StrTy = Context.CharTy; 1438 if (Literal.isWide()) 1439 StrTy = Context.getWCharType(); 1440 else if (Literal.isUTF16()) 1441 StrTy = Context.Char16Ty; 1442 else if (Literal.isUTF32()) 1443 StrTy = Context.Char32Ty; 1444 else if (Literal.isPascal()) 1445 StrTy = Context.UnsignedCharTy; 1446 1447 StringLiteral::StringKind Kind = StringLiteral::Ascii; 1448 if (Literal.isWide()) 1449 Kind = StringLiteral::Wide; 1450 else if (Literal.isUTF8()) 1451 Kind = StringLiteral::UTF8; 1452 else if (Literal.isUTF16()) 1453 Kind = StringLiteral::UTF16; 1454 else if (Literal.isUTF32()) 1455 Kind = StringLiteral::UTF32; 1456 1457 // A C++ string literal has a const-qualified element type (C++ 2.13.4p1). 1458 if (getLangOpts().CPlusPlus || getLangOpts().ConstStrings) 1459 StrTy.addConst(); 1460 1461 // Get an array type for the string, according to C99 6.4.5. This includes 1462 // the nul terminator character as well as the string length for pascal 1463 // strings. 1464 StrTy = Context.getConstantArrayType(StrTy, 1465 llvm::APInt(32, Literal.GetNumStringChars()+1), 1466 ArrayType::Normal, 0); 1467 1468 // Pass &StringTokLocs[0], StringTokLocs.size() to factory! 1469 StringLiteral *Lit = StringLiteral::Create(Context, Literal.GetString(), 1470 Kind, Literal.Pascal, StrTy, 1471 &StringTokLocs[0], 1472 StringTokLocs.size()); 1473 if (Literal.getUDSuffix().empty()) 1474 return Owned(Lit); 1475 1476 // We're building a user-defined literal. 1477 IdentifierInfo *UDSuffix = &Context.Idents.get(Literal.getUDSuffix()); 1478 SourceLocation UDSuffixLoc = 1479 getUDSuffixLoc(*this, StringTokLocs[Literal.getUDSuffixToken()], 1480 Literal.getUDSuffixOffset()); 1481 1482 // Make sure we're allowed user-defined literals here. 1483 if (!UDLScope) 1484 return ExprError(Diag(UDSuffixLoc, diag::err_invalid_string_udl)); 1485 1486 // C++11 [lex.ext]p5: The literal L is treated as a call of the form 1487 // operator "" X (str, len) 1488 QualType SizeType = Context.getSizeType(); 1489 llvm::APInt Len(Context.getIntWidth(SizeType), Literal.GetNumStringChars()); 1490 IntegerLiteral *LenArg = IntegerLiteral::Create(Context, Len, SizeType, 1491 StringTokLocs[0]); 1492 Expr *Args[] = { Lit, LenArg }; 1493 return BuildCookedLiteralOperatorCall(*this, UDLScope, UDSuffix, UDSuffixLoc, 1494 Args, StringTokLocs.back()); 1495} 1496 1497ExprResult 1498Sema::BuildDeclRefExpr(ValueDecl *D, QualType Ty, ExprValueKind VK, 1499 SourceLocation Loc, 1500 const CXXScopeSpec *SS) { 1501 DeclarationNameInfo NameInfo(D->getDeclName(), Loc); 1502 return BuildDeclRefExpr(D, Ty, VK, NameInfo, SS); 1503} 1504 1505/// BuildDeclRefExpr - Build an expression that references a 1506/// declaration that does not require a closure capture. 1507ExprResult 1508Sema::BuildDeclRefExpr(ValueDecl *D, QualType Ty, ExprValueKind VK, 1509 const DeclarationNameInfo &NameInfo, 1510 const CXXScopeSpec *SS, NamedDecl *FoundD) { 1511 if (getLangOpts().CUDA) 1512 if (const FunctionDecl *Caller = dyn_cast<FunctionDecl>(CurContext)) 1513 if (const FunctionDecl *Callee = dyn_cast<FunctionDecl>(D)) { 1514 CUDAFunctionTarget CallerTarget = IdentifyCUDATarget(Caller), 1515 CalleeTarget = IdentifyCUDATarget(Callee); 1516 if (CheckCUDATarget(CallerTarget, CalleeTarget)) { 1517 Diag(NameInfo.getLoc(), diag::err_ref_bad_target) 1518 << CalleeTarget << D->getIdentifier() << CallerTarget; 1519 Diag(D->getLocation(), diag::note_previous_decl) 1520 << D->getIdentifier(); 1521 return ExprError(); 1522 } 1523 } 1524 1525 bool refersToEnclosingScope = 1526 (CurContext != D->getDeclContext() && 1527 D->getDeclContext()->isFunctionOrMethod()); 1528 1529 DeclRefExpr *E = DeclRefExpr::Create(Context, 1530 SS ? SS->getWithLocInContext(Context) 1531 : NestedNameSpecifierLoc(), 1532 SourceLocation(), 1533 D, refersToEnclosingScope, 1534 NameInfo, Ty, VK, FoundD); 1535 1536 MarkDeclRefReferenced(E); 1537 1538 if (getLangOpts().ObjCARCWeak && isa<VarDecl>(D) && 1539 Ty.getObjCLifetime() == Qualifiers::OCL_Weak) { 1540 DiagnosticsEngine::Level Level = 1541 Diags.getDiagnosticLevel(diag::warn_arc_repeated_use_of_weak, 1542 E->getLocStart()); 1543 if (Level != DiagnosticsEngine::Ignored) 1544 getCurFunction()->recordUseOfWeak(E); 1545 } 1546 1547 // Just in case we're building an illegal pointer-to-member. 1548 FieldDecl *FD = dyn_cast<FieldDecl>(D); 1549 if (FD && FD->isBitField()) 1550 E->setObjectKind(OK_BitField); 1551 1552 return Owned(E); 1553} 1554 1555/// Decomposes the given name into a DeclarationNameInfo, its location, and 1556/// possibly a list of template arguments. 1557/// 1558/// If this produces template arguments, it is permitted to call 1559/// DecomposeTemplateName. 1560/// 1561/// This actually loses a lot of source location information for 1562/// non-standard name kinds; we should consider preserving that in 1563/// some way. 1564void 1565Sema::DecomposeUnqualifiedId(const UnqualifiedId &Id, 1566 TemplateArgumentListInfo &Buffer, 1567 DeclarationNameInfo &NameInfo, 1568 const TemplateArgumentListInfo *&TemplateArgs) { 1569 if (Id.getKind() == UnqualifiedId::IK_TemplateId) { 1570 Buffer.setLAngleLoc(Id.TemplateId->LAngleLoc); 1571 Buffer.setRAngleLoc(Id.TemplateId->RAngleLoc); 1572 1573 ASTTemplateArgsPtr TemplateArgsPtr(Id.TemplateId->getTemplateArgs(), 1574 Id.TemplateId->NumArgs); 1575 translateTemplateArguments(TemplateArgsPtr, Buffer); 1576 1577 TemplateName TName = Id.TemplateId->Template.get(); 1578 SourceLocation TNameLoc = Id.TemplateId->TemplateNameLoc; 1579 NameInfo = Context.getNameForTemplate(TName, TNameLoc); 1580 TemplateArgs = &Buffer; 1581 } else { 1582 NameInfo = GetNameFromUnqualifiedId(Id); 1583 TemplateArgs = 0; 1584 } 1585} 1586 1587/// Diagnose an empty lookup. 1588/// 1589/// \return false if new lookup candidates were found 1590bool Sema::DiagnoseEmptyLookup(Scope *S, CXXScopeSpec &SS, LookupResult &R, 1591 CorrectionCandidateCallback &CCC, 1592 TemplateArgumentListInfo *ExplicitTemplateArgs, 1593 llvm::ArrayRef<Expr *> Args) { 1594 DeclarationName Name = R.getLookupName(); 1595 1596 unsigned diagnostic = diag::err_undeclared_var_use; 1597 unsigned diagnostic_suggest = diag::err_undeclared_var_use_suggest; 1598 if (Name.getNameKind() == DeclarationName::CXXOperatorName || 1599 Name.getNameKind() == DeclarationName::CXXLiteralOperatorName || 1600 Name.getNameKind() == DeclarationName::CXXConversionFunctionName) { 1601 diagnostic = diag::err_undeclared_use; 1602 diagnostic_suggest = diag::err_undeclared_use_suggest; 1603 } 1604 1605 // If the original lookup was an unqualified lookup, fake an 1606 // unqualified lookup. This is useful when (for example) the 1607 // original lookup would not have found something because it was a 1608 // dependent name. 1609 DeclContext *DC = (SS.isEmpty() && !CallsUndergoingInstantiation.empty()) 1610 ? CurContext : 0; 1611 while (DC) { 1612 if (isa<CXXRecordDecl>(DC)) { 1613 LookupQualifiedName(R, DC); 1614 1615 if (!R.empty()) { 1616 // Don't give errors about ambiguities in this lookup. 1617 R.suppressDiagnostics(); 1618 1619 // During a default argument instantiation the CurContext points 1620 // to a CXXMethodDecl; but we can't apply a this-> fixit inside a 1621 // function parameter list, hence add an explicit check. 1622 bool isDefaultArgument = !ActiveTemplateInstantiations.empty() && 1623 ActiveTemplateInstantiations.back().Kind == 1624 ActiveTemplateInstantiation::DefaultFunctionArgumentInstantiation; 1625 CXXMethodDecl *CurMethod = dyn_cast<CXXMethodDecl>(CurContext); 1626 bool isInstance = CurMethod && 1627 CurMethod->isInstance() && 1628 DC == CurMethod->getParent() && !isDefaultArgument; 1629 1630 1631 // Give a code modification hint to insert 'this->'. 1632 // TODO: fixit for inserting 'Base<T>::' in the other cases. 1633 // Actually quite difficult! 1634 if (getLangOpts().MicrosoftMode) 1635 diagnostic = diag::warn_found_via_dependent_bases_lookup; 1636 if (isInstance) { 1637 Diag(R.getNameLoc(), diagnostic) << Name 1638 << FixItHint::CreateInsertion(R.getNameLoc(), "this->"); 1639 UnresolvedLookupExpr *ULE = cast<UnresolvedLookupExpr>( 1640 CallsUndergoingInstantiation.back()->getCallee()); 1641 1642 CXXMethodDecl *DepMethod; 1643 if (CurMethod->isDependentContext()) 1644 DepMethod = CurMethod; 1645 else if (CurMethod->getTemplatedKind() == 1646 FunctionDecl::TK_FunctionTemplateSpecialization) 1647 DepMethod = cast<CXXMethodDecl>(CurMethod->getPrimaryTemplate()-> 1648 getInstantiatedFromMemberTemplate()->getTemplatedDecl()); 1649 else 1650 DepMethod = cast<CXXMethodDecl>( 1651 CurMethod->getInstantiatedFromMemberFunction()); 1652 assert(DepMethod && "No template pattern found"); 1653 1654 QualType DepThisType = DepMethod->getThisType(Context); 1655 CheckCXXThisCapture(R.getNameLoc()); 1656 CXXThisExpr *DepThis = new (Context) CXXThisExpr( 1657 R.getNameLoc(), DepThisType, false); 1658 TemplateArgumentListInfo TList; 1659 if (ULE->hasExplicitTemplateArgs()) 1660 ULE->copyTemplateArgumentsInto(TList); 1661 1662 CXXScopeSpec SS; 1663 SS.Adopt(ULE->getQualifierLoc()); 1664 CXXDependentScopeMemberExpr *DepExpr = 1665 CXXDependentScopeMemberExpr::Create( 1666 Context, DepThis, DepThisType, true, SourceLocation(), 1667 SS.getWithLocInContext(Context), 1668 ULE->getTemplateKeywordLoc(), 0, 1669 R.getLookupNameInfo(), 1670 ULE->hasExplicitTemplateArgs() ? &TList : 0); 1671 CallsUndergoingInstantiation.back()->setCallee(DepExpr); 1672 } else { 1673 Diag(R.getNameLoc(), diagnostic) << Name; 1674 } 1675 1676 // Do we really want to note all of these? 1677 for (LookupResult::iterator I = R.begin(), E = R.end(); I != E; ++I) 1678 Diag((*I)->getLocation(), diag::note_dependent_var_use); 1679 1680 // Return true if we are inside a default argument instantiation 1681 // and the found name refers to an instance member function, otherwise 1682 // the function calling DiagnoseEmptyLookup will try to create an 1683 // implicit member call and this is wrong for default argument. 1684 if (isDefaultArgument && ((*R.begin())->isCXXInstanceMember())) { 1685 Diag(R.getNameLoc(), diag::err_member_call_without_object); 1686 return true; 1687 } 1688 1689 // Tell the callee to try to recover. 1690 return false; 1691 } 1692 1693 R.clear(); 1694 } 1695 1696 // In Microsoft mode, if we are performing lookup from within a friend 1697 // function definition declared at class scope then we must set 1698 // DC to the lexical parent to be able to search into the parent 1699 // class. 1700 if (getLangOpts().MicrosoftMode && isa<FunctionDecl>(DC) && 1701 cast<FunctionDecl>(DC)->getFriendObjectKind() && 1702 DC->getLexicalParent()->isRecord()) 1703 DC = DC->getLexicalParent(); 1704 else 1705 DC = DC->getParent(); 1706 } 1707 1708 // We didn't find anything, so try to correct for a typo. 1709 TypoCorrection Corrected; 1710 if (S && (Corrected = CorrectTypo(R.getLookupNameInfo(), R.getLookupKind(), 1711 S, &SS, CCC))) { 1712 std::string CorrectedStr(Corrected.getAsString(getLangOpts())); 1713 std::string CorrectedQuotedStr(Corrected.getQuoted(getLangOpts())); 1714 R.setLookupName(Corrected.getCorrection()); 1715 1716 if (NamedDecl *ND = Corrected.getCorrectionDecl()) { 1717 if (Corrected.isOverloaded()) { 1718 OverloadCandidateSet OCS(R.getNameLoc()); 1719 OverloadCandidateSet::iterator Best; 1720 for (TypoCorrection::decl_iterator CD = Corrected.begin(), 1721 CDEnd = Corrected.end(); 1722 CD != CDEnd; ++CD) { 1723 if (FunctionTemplateDecl *FTD = 1724 dyn_cast<FunctionTemplateDecl>(*CD)) 1725 AddTemplateOverloadCandidate( 1726 FTD, DeclAccessPair::make(FTD, AS_none), ExplicitTemplateArgs, 1727 Args, OCS); 1728 else if (FunctionDecl *FD = dyn_cast<FunctionDecl>(*CD)) 1729 if (!ExplicitTemplateArgs || ExplicitTemplateArgs->size() == 0) 1730 AddOverloadCandidate(FD, DeclAccessPair::make(FD, AS_none), 1731 Args, OCS); 1732 } 1733 switch (OCS.BestViableFunction(*this, R.getNameLoc(), Best)) { 1734 case OR_Success: 1735 ND = Best->Function; 1736 break; 1737 default: 1738 break; 1739 } 1740 } 1741 R.addDecl(ND); 1742 if (isa<ValueDecl>(ND) || isa<FunctionTemplateDecl>(ND)) { 1743 if (SS.isEmpty()) 1744 Diag(R.getNameLoc(), diagnostic_suggest) << Name << CorrectedQuotedStr 1745 << FixItHint::CreateReplacement(R.getNameLoc(), CorrectedStr); 1746 else 1747 Diag(R.getNameLoc(), diag::err_no_member_suggest) 1748 << Name << computeDeclContext(SS, false) << CorrectedQuotedStr 1749 << SS.getRange() 1750 << FixItHint::CreateReplacement(Corrected.getCorrectionRange(), 1751 CorrectedStr); 1752 1753 unsigned diag = isa<ImplicitParamDecl>(ND) 1754 ? diag::note_implicit_param_decl 1755 : diag::note_previous_decl; 1756 1757 Diag(ND->getLocation(), diag) 1758 << CorrectedQuotedStr; 1759 1760 // Tell the callee to try to recover. 1761 return false; 1762 } 1763 1764 if (isa<TypeDecl>(ND) || isa<ObjCInterfaceDecl>(ND)) { 1765 // FIXME: If we ended up with a typo for a type name or 1766 // Objective-C class name, we're in trouble because the parser 1767 // is in the wrong place to recover. Suggest the typo 1768 // correction, but don't make it a fix-it since we're not going 1769 // to recover well anyway. 1770 if (SS.isEmpty()) 1771 Diag(R.getNameLoc(), diagnostic_suggest) 1772 << Name << CorrectedQuotedStr; 1773 else 1774 Diag(R.getNameLoc(), diag::err_no_member_suggest) 1775 << Name << computeDeclContext(SS, false) << CorrectedQuotedStr 1776 << SS.getRange(); 1777 1778 // Don't try to recover; it won't work. 1779 return true; 1780 } 1781 } else { 1782 // FIXME: We found a keyword. Suggest it, but don't provide a fix-it 1783 // because we aren't able to recover. 1784 if (SS.isEmpty()) 1785 Diag(R.getNameLoc(), diagnostic_suggest) << Name << CorrectedQuotedStr; 1786 else 1787 Diag(R.getNameLoc(), diag::err_no_member_suggest) 1788 << Name << computeDeclContext(SS, false) << CorrectedQuotedStr 1789 << SS.getRange(); 1790 return true; 1791 } 1792 } 1793 R.clear(); 1794 1795 // Emit a special diagnostic for failed member lookups. 1796 // FIXME: computing the declaration context might fail here (?) 1797 if (!SS.isEmpty()) { 1798 Diag(R.getNameLoc(), diag::err_no_member) 1799 << Name << computeDeclContext(SS, false) 1800 << SS.getRange(); 1801 return true; 1802 } 1803 1804 // Give up, we can't recover. 1805 Diag(R.getNameLoc(), diagnostic) << Name; 1806 return true; 1807} 1808 1809ExprResult Sema::ActOnIdExpression(Scope *S, 1810 CXXScopeSpec &SS, 1811 SourceLocation TemplateKWLoc, 1812 UnqualifiedId &Id, 1813 bool HasTrailingLParen, 1814 bool IsAddressOfOperand, 1815 CorrectionCandidateCallback *CCC) { 1816 assert(!(IsAddressOfOperand && HasTrailingLParen) && 1817 "cannot be direct & operand and have a trailing lparen"); 1818 1819 if (SS.isInvalid()) 1820 return ExprError(); 1821 1822 TemplateArgumentListInfo TemplateArgsBuffer; 1823 1824 // Decompose the UnqualifiedId into the following data. 1825 DeclarationNameInfo NameInfo; 1826 const TemplateArgumentListInfo *TemplateArgs; 1827 DecomposeUnqualifiedId(Id, TemplateArgsBuffer, NameInfo, TemplateArgs); 1828 1829 DeclarationName Name = NameInfo.getName(); 1830 IdentifierInfo *II = Name.getAsIdentifierInfo(); 1831 SourceLocation NameLoc = NameInfo.getLoc(); 1832 1833 // C++ [temp.dep.expr]p3: 1834 // An id-expression is type-dependent if it contains: 1835 // -- an identifier that was declared with a dependent type, 1836 // (note: handled after lookup) 1837 // -- a template-id that is dependent, 1838 // (note: handled in BuildTemplateIdExpr) 1839 // -- a conversion-function-id that specifies a dependent type, 1840 // -- a nested-name-specifier that contains a class-name that 1841 // names a dependent type. 1842 // Determine whether this is a member of an unknown specialization; 1843 // we need to handle these differently. 1844 bool DependentID = false; 1845 if (Name.getNameKind() == DeclarationName::CXXConversionFunctionName && 1846 Name.getCXXNameType()->isDependentType()) { 1847 DependentID = true; 1848 } else if (SS.isSet()) { 1849 if (DeclContext *DC = computeDeclContext(SS, false)) { 1850 if (RequireCompleteDeclContext(SS, DC)) 1851 return ExprError(); 1852 } else { 1853 DependentID = true; 1854 } 1855 } 1856 1857 if (DependentID) 1858 return ActOnDependentIdExpression(SS, TemplateKWLoc, NameInfo, 1859 IsAddressOfOperand, TemplateArgs); 1860 1861 // Perform the required lookup. 1862 LookupResult R(*this, NameInfo, 1863 (Id.getKind() == UnqualifiedId::IK_ImplicitSelfParam) 1864 ? LookupObjCImplicitSelfParam : LookupOrdinaryName); 1865 if (TemplateArgs) { 1866 // Lookup the template name again to correctly establish the context in 1867 // which it was found. This is really unfortunate as we already did the 1868 // lookup to determine that it was a template name in the first place. If 1869 // this becomes a performance hit, we can work harder to preserve those 1870 // results until we get here but it's likely not worth it. 1871 bool MemberOfUnknownSpecialization; 1872 LookupTemplateName(R, S, SS, QualType(), /*EnteringContext=*/false, 1873 MemberOfUnknownSpecialization); 1874 1875 if (MemberOfUnknownSpecialization || 1876 (R.getResultKind() == LookupResult::NotFoundInCurrentInstantiation)) 1877 return ActOnDependentIdExpression(SS, TemplateKWLoc, NameInfo, 1878 IsAddressOfOperand, TemplateArgs); 1879 } else { 1880 bool IvarLookupFollowUp = II && !SS.isSet() && getCurMethodDecl(); 1881 LookupParsedName(R, S, &SS, !IvarLookupFollowUp); 1882 1883 // If the result might be in a dependent base class, this is a dependent 1884 // id-expression. 1885 if (R.getResultKind() == LookupResult::NotFoundInCurrentInstantiation) 1886 return ActOnDependentIdExpression(SS, TemplateKWLoc, NameInfo, 1887 IsAddressOfOperand, TemplateArgs); 1888 1889 // If this reference is in an Objective-C method, then we need to do 1890 // some special Objective-C lookup, too. 1891 if (IvarLookupFollowUp) { 1892 ExprResult E(LookupInObjCMethod(R, S, II, true)); 1893 if (E.isInvalid()) 1894 return ExprError(); 1895 1896 if (Expr *Ex = E.takeAs<Expr>()) 1897 return Owned(Ex); 1898 } 1899 } 1900 1901 if (R.isAmbiguous()) 1902 return ExprError(); 1903 1904 // Determine whether this name might be a candidate for 1905 // argument-dependent lookup. 1906 bool ADL = UseArgumentDependentLookup(SS, R, HasTrailingLParen); 1907 1908 if (R.empty() && !ADL) { 1909 // Otherwise, this could be an implicitly declared function reference (legal 1910 // in C90, extension in C99, forbidden in C++). 1911 if (HasTrailingLParen && II && !getLangOpts().CPlusPlus) { 1912 NamedDecl *D = ImplicitlyDefineFunction(NameLoc, *II, S); 1913 if (D) R.addDecl(D); 1914 } 1915 1916 // If this name wasn't predeclared and if this is not a function 1917 // call, diagnose the problem. 1918 if (R.empty()) { 1919 1920 // In Microsoft mode, if we are inside a template class member function 1921 // and we can't resolve an identifier then assume the identifier is type 1922 // dependent. The goal is to postpone name lookup to instantiation time 1923 // to be able to search into type dependent base classes. 1924 if (getLangOpts().MicrosoftMode && CurContext->isDependentContext() && 1925 isa<CXXMethodDecl>(CurContext)) 1926 return ActOnDependentIdExpression(SS, TemplateKWLoc, NameInfo, 1927 IsAddressOfOperand, TemplateArgs); 1928 1929 CorrectionCandidateCallback DefaultValidator; 1930 if (DiagnoseEmptyLookup(S, SS, R, CCC ? *CCC : DefaultValidator)) 1931 return ExprError(); 1932 1933 assert(!R.empty() && 1934 "DiagnoseEmptyLookup returned false but added no results"); 1935 1936 // If we found an Objective-C instance variable, let 1937 // LookupInObjCMethod build the appropriate expression to 1938 // reference the ivar. 1939 if (ObjCIvarDecl *Ivar = R.getAsSingle<ObjCIvarDecl>()) { 1940 R.clear(); 1941 ExprResult E(LookupInObjCMethod(R, S, Ivar->getIdentifier())); 1942 // In a hopelessly buggy code, Objective-C instance variable 1943 // lookup fails and no expression will be built to reference it. 1944 if (!E.isInvalid() && !E.get()) 1945 return ExprError(); 1946 return E; 1947 } 1948 } 1949 } 1950 1951 // This is guaranteed from this point on. 1952 assert(!R.empty() || ADL); 1953 1954 // Check whether this might be a C++ implicit instance member access. 1955 // C++ [class.mfct.non-static]p3: 1956 // When an id-expression that is not part of a class member access 1957 // syntax and not used to form a pointer to member is used in the 1958 // body of a non-static member function of class X, if name lookup 1959 // resolves the name in the id-expression to a non-static non-type 1960 // member of some class C, the id-expression is transformed into a 1961 // class member access expression using (*this) as the 1962 // postfix-expression to the left of the . operator. 1963 // 1964 // But we don't actually need to do this for '&' operands if R 1965 // resolved to a function or overloaded function set, because the 1966 // expression is ill-formed if it actually works out to be a 1967 // non-static member function: 1968 // 1969 // C++ [expr.ref]p4: 1970 // Otherwise, if E1.E2 refers to a non-static member function. . . 1971 // [t]he expression can be used only as the left-hand operand of a 1972 // member function call. 1973 // 1974 // There are other safeguards against such uses, but it's important 1975 // to get this right here so that we don't end up making a 1976 // spuriously dependent expression if we're inside a dependent 1977 // instance method. 1978 if (!R.empty() && (*R.begin())->isCXXClassMember()) { 1979 bool MightBeImplicitMember; 1980 if (!IsAddressOfOperand) 1981 MightBeImplicitMember = true; 1982 else if (!SS.isEmpty()) 1983 MightBeImplicitMember = false; 1984 else if (R.isOverloadedResult()) 1985 MightBeImplicitMember = false; 1986 else if (R.isUnresolvableResult()) 1987 MightBeImplicitMember = true; 1988 else 1989 MightBeImplicitMember = isa<FieldDecl>(R.getFoundDecl()) || 1990 isa<IndirectFieldDecl>(R.getFoundDecl()); 1991 1992 if (MightBeImplicitMember) 1993 return BuildPossibleImplicitMemberExpr(SS, TemplateKWLoc, 1994 R, TemplateArgs); 1995 } 1996 1997 if (TemplateArgs || TemplateKWLoc.isValid()) 1998 return BuildTemplateIdExpr(SS, TemplateKWLoc, R, ADL, TemplateArgs); 1999 2000 return BuildDeclarationNameExpr(SS, R, ADL); 2001} 2002 2003/// BuildQualifiedDeclarationNameExpr - Build a C++ qualified 2004/// declaration name, generally during template instantiation. 2005/// There's a large number of things which don't need to be done along 2006/// this path. 2007ExprResult 2008Sema::BuildQualifiedDeclarationNameExpr(CXXScopeSpec &SS, 2009 const DeclarationNameInfo &NameInfo, 2010 bool IsAddressOfOperand) { 2011 DeclContext *DC = computeDeclContext(SS, false); 2012 if (!DC) 2013 return BuildDependentDeclRefExpr(SS, /*TemplateKWLoc=*/SourceLocation(), 2014 NameInfo, /*TemplateArgs=*/0); 2015 2016 if (RequireCompleteDeclContext(SS, DC)) 2017 return ExprError(); 2018 2019 LookupResult R(*this, NameInfo, LookupOrdinaryName); 2020 LookupQualifiedName(R, DC); 2021 2022 if (R.isAmbiguous()) 2023 return ExprError(); 2024 2025 if (R.getResultKind() == LookupResult::NotFoundInCurrentInstantiation) 2026 return BuildDependentDeclRefExpr(SS, /*TemplateKWLoc=*/SourceLocation(), 2027 NameInfo, /*TemplateArgs=*/0); 2028 2029 if (R.empty()) { 2030 Diag(NameInfo.getLoc(), diag::err_no_member) 2031 << NameInfo.getName() << DC << SS.getRange(); 2032 return ExprError(); 2033 } 2034 2035 // Defend against this resolving to an implicit member access. We usually 2036 // won't get here if this might be a legitimate a class member (we end up in 2037 // BuildMemberReferenceExpr instead), but this can be valid if we're forming 2038 // a pointer-to-member or in an unevaluated context in C++11. 2039 if (!R.empty() && (*R.begin())->isCXXClassMember() && !IsAddressOfOperand) 2040 return BuildPossibleImplicitMemberExpr(SS, 2041 /*TemplateKWLoc=*/SourceLocation(), 2042 R, /*TemplateArgs=*/0); 2043 2044 return BuildDeclarationNameExpr(SS, R, /* ADL */ false); 2045} 2046 2047/// LookupInObjCMethod - The parser has read a name in, and Sema has 2048/// detected that we're currently inside an ObjC method. Perform some 2049/// additional lookup. 2050/// 2051/// Ideally, most of this would be done by lookup, but there's 2052/// actually quite a lot of extra work involved. 2053/// 2054/// Returns a null sentinel to indicate trivial success. 2055ExprResult 2056Sema::LookupInObjCMethod(LookupResult &Lookup, Scope *S, 2057 IdentifierInfo *II, bool AllowBuiltinCreation) { 2058 SourceLocation Loc = Lookup.getNameLoc(); 2059 ObjCMethodDecl *CurMethod = getCurMethodDecl(); 2060 2061 // Check for error condition which is already reported. 2062 if (!CurMethod) 2063 return ExprError(); 2064 2065 // There are two cases to handle here. 1) scoped lookup could have failed, 2066 // in which case we should look for an ivar. 2) scoped lookup could have 2067 // found a decl, but that decl is outside the current instance method (i.e. 2068 // a global variable). In these two cases, we do a lookup for an ivar with 2069 // this name, if the lookup sucedes, we replace it our current decl. 2070 2071 // If we're in a class method, we don't normally want to look for 2072 // ivars. But if we don't find anything else, and there's an 2073 // ivar, that's an error. 2074 bool IsClassMethod = CurMethod->isClassMethod(); 2075 2076 bool LookForIvars; 2077 if (Lookup.empty()) 2078 LookForIvars = true; 2079 else if (IsClassMethod) 2080 LookForIvars = false; 2081 else 2082 LookForIvars = (Lookup.isSingleResult() && 2083 Lookup.getFoundDecl()->isDefinedOutsideFunctionOrMethod()); 2084 ObjCInterfaceDecl *IFace = 0; 2085 if (LookForIvars) { 2086 IFace = CurMethod->getClassInterface(); 2087 ObjCInterfaceDecl *ClassDeclared; 2088 ObjCIvarDecl *IV = 0; 2089 if (IFace && (IV = IFace->lookupInstanceVariable(II, ClassDeclared))) { 2090 // Diagnose using an ivar in a class method. 2091 if (IsClassMethod) 2092 return ExprError(Diag(Loc, diag::error_ivar_use_in_class_method) 2093 << IV->getDeclName()); 2094 2095 // If we're referencing an invalid decl, just return this as a silent 2096 // error node. The error diagnostic was already emitted on the decl. 2097 if (IV->isInvalidDecl()) 2098 return ExprError(); 2099 2100 // Check if referencing a field with __attribute__((deprecated)). 2101 if (DiagnoseUseOfDecl(IV, Loc)) 2102 return ExprError(); 2103 2104 // Diagnose the use of an ivar outside of the declaring class. 2105 if (IV->getAccessControl() == ObjCIvarDecl::Private && 2106 !declaresSameEntity(ClassDeclared, IFace) && 2107 !getLangOpts().DebuggerSupport) 2108 Diag(Loc, diag::error_private_ivar_access) << IV->getDeclName(); 2109 2110 // FIXME: This should use a new expr for a direct reference, don't 2111 // turn this into Self->ivar, just return a BareIVarExpr or something. 2112 IdentifierInfo &II = Context.Idents.get("self"); 2113 UnqualifiedId SelfName; 2114 SelfName.setIdentifier(&II, SourceLocation()); 2115 SelfName.setKind(UnqualifiedId::IK_ImplicitSelfParam); 2116 CXXScopeSpec SelfScopeSpec; 2117 SourceLocation TemplateKWLoc; 2118 ExprResult SelfExpr = ActOnIdExpression(S, SelfScopeSpec, TemplateKWLoc, 2119 SelfName, false, false); 2120 if (SelfExpr.isInvalid()) 2121 return ExprError(); 2122 2123 SelfExpr = DefaultLvalueConversion(SelfExpr.take()); 2124 if (SelfExpr.isInvalid()) 2125 return ExprError(); 2126 2127 MarkAnyDeclReferenced(Loc, IV, true); 2128 2129 ObjCMethodFamily MF = CurMethod->getMethodFamily(); 2130 if (MF != OMF_init && MF != OMF_dealloc && MF != OMF_finalize && 2131 !IvarBacksCurrentMethodAccessor(IFace, CurMethod, IV)) 2132 Diag(Loc, diag::warn_direct_ivar_access) << IV->getDeclName(); 2133 2134 ObjCIvarRefExpr *Result = new (Context) ObjCIvarRefExpr(IV, IV->getType(), 2135 Loc, IV->getLocation(), 2136 SelfExpr.take(), 2137 true, true); 2138 2139 if (getLangOpts().ObjCAutoRefCount) { 2140 if (IV->getType().getObjCLifetime() == Qualifiers::OCL_Weak) { 2141 DiagnosticsEngine::Level Level = 2142 Diags.getDiagnosticLevel(diag::warn_arc_repeated_use_of_weak, Loc); 2143 if (Level != DiagnosticsEngine::Ignored) 2144 getCurFunction()->recordUseOfWeak(Result); 2145 } 2146 if (CurContext->isClosure()) 2147 Diag(Loc, diag::warn_implicitly_retains_self) 2148 << FixItHint::CreateInsertion(Loc, "self->"); 2149 } 2150 2151 return Owned(Result); 2152 } 2153 } else if (CurMethod->isInstanceMethod()) { 2154 // We should warn if a local variable hides an ivar. 2155 if (ObjCInterfaceDecl *IFace = CurMethod->getClassInterface()) { 2156 ObjCInterfaceDecl *ClassDeclared; 2157 if (ObjCIvarDecl *IV = IFace->lookupInstanceVariable(II, ClassDeclared)) { 2158 if (IV->getAccessControl() != ObjCIvarDecl::Private || 2159 declaresSameEntity(IFace, ClassDeclared)) 2160 Diag(Loc, diag::warn_ivar_use_hidden) << IV->getDeclName(); 2161 } 2162 } 2163 } else if (Lookup.isSingleResult() && 2164 Lookup.getFoundDecl()->isDefinedOutsideFunctionOrMethod()) { 2165 // If accessing a stand-alone ivar in a class method, this is an error. 2166 if (const ObjCIvarDecl *IV = dyn_cast<ObjCIvarDecl>(Lookup.getFoundDecl())) 2167 return ExprError(Diag(Loc, diag::error_ivar_use_in_class_method) 2168 << IV->getDeclName()); 2169 } 2170 2171 if (Lookup.empty() && II && AllowBuiltinCreation) { 2172 // FIXME. Consolidate this with similar code in LookupName. 2173 if (unsigned BuiltinID = II->getBuiltinID()) { 2174 if (!(getLangOpts().CPlusPlus && 2175 Context.BuiltinInfo.isPredefinedLibFunction(BuiltinID))) { 2176 NamedDecl *D = LazilyCreateBuiltin((IdentifierInfo *)II, BuiltinID, 2177 S, Lookup.isForRedeclaration(), 2178 Lookup.getNameLoc()); 2179 if (D) Lookup.addDecl(D); 2180 } 2181 } 2182 } 2183 // Sentinel value saying that we didn't do anything special. 2184 return Owned((Expr*) 0); 2185} 2186 2187/// \brief Cast a base object to a member's actual type. 2188/// 2189/// Logically this happens in three phases: 2190/// 2191/// * First we cast from the base type to the naming class. 2192/// The naming class is the class into which we were looking 2193/// when we found the member; it's the qualifier type if a 2194/// qualifier was provided, and otherwise it's the base type. 2195/// 2196/// * Next we cast from the naming class to the declaring class. 2197/// If the member we found was brought into a class's scope by 2198/// a using declaration, this is that class; otherwise it's 2199/// the class declaring the member. 2200/// 2201/// * Finally we cast from the declaring class to the "true" 2202/// declaring class of the member. This conversion does not 2203/// obey access control. 2204ExprResult 2205Sema::PerformObjectMemberConversion(Expr *From, 2206 NestedNameSpecifier *Qualifier, 2207 NamedDecl *FoundDecl, 2208 NamedDecl *Member) { 2209 CXXRecordDecl *RD = dyn_cast<CXXRecordDecl>(Member->getDeclContext()); 2210 if (!RD) 2211 return Owned(From); 2212 2213 QualType DestRecordType; 2214 QualType DestType; 2215 QualType FromRecordType; 2216 QualType FromType = From->getType(); 2217 bool PointerConversions = false; 2218 if (isa<FieldDecl>(Member)) { 2219 DestRecordType = Context.getCanonicalType(Context.getTypeDeclType(RD)); 2220 2221 if (FromType->getAs<PointerType>()) { 2222 DestType = Context.getPointerType(DestRecordType); 2223 FromRecordType = FromType->getPointeeType(); 2224 PointerConversions = true; 2225 } else { 2226 DestType = DestRecordType; 2227 FromRecordType = FromType; 2228 } 2229 } else if (CXXMethodDecl *Method = dyn_cast<CXXMethodDecl>(Member)) { 2230 if (Method->isStatic()) 2231 return Owned(From); 2232 2233 DestType = Method->getThisType(Context); 2234 DestRecordType = DestType->getPointeeType(); 2235 2236 if (FromType->getAs<PointerType>()) { 2237 FromRecordType = FromType->getPointeeType(); 2238 PointerConversions = true; 2239 } else { 2240 FromRecordType = FromType; 2241 DestType = DestRecordType; 2242 } 2243 } else { 2244 // No conversion necessary. 2245 return Owned(From); 2246 } 2247 2248 if (DestType->isDependentType() || FromType->isDependentType()) 2249 return Owned(From); 2250 2251 // If the unqualified types are the same, no conversion is necessary. 2252 if (Context.hasSameUnqualifiedType(FromRecordType, DestRecordType)) 2253 return Owned(From); 2254 2255 SourceRange FromRange = From->getSourceRange(); 2256 SourceLocation FromLoc = FromRange.getBegin(); 2257 2258 ExprValueKind VK = From->getValueKind(); 2259 2260 // C++ [class.member.lookup]p8: 2261 // [...] Ambiguities can often be resolved by qualifying a name with its 2262 // class name. 2263 // 2264 // If the member was a qualified name and the qualified referred to a 2265 // specific base subobject type, we'll cast to that intermediate type 2266 // first and then to the object in which the member is declared. That allows 2267 // one to resolve ambiguities in, e.g., a diamond-shaped hierarchy such as: 2268 // 2269 // class Base { public: int x; }; 2270 // class Derived1 : public Base { }; 2271 // class Derived2 : public Base { }; 2272 // class VeryDerived : public Derived1, public Derived2 { void f(); }; 2273 // 2274 // void VeryDerived::f() { 2275 // x = 17; // error: ambiguous base subobjects 2276 // Derived1::x = 17; // okay, pick the Base subobject of Derived1 2277 // } 2278 if (Qualifier) { 2279 QualType QType = QualType(Qualifier->getAsType(), 0); 2280 assert(!QType.isNull() && "lookup done with dependent qualifier?"); 2281 assert(QType->isRecordType() && "lookup done with non-record type"); 2282 2283 QualType QRecordType = QualType(QType->getAs<RecordType>(), 0); 2284 2285 // In C++98, the qualifier type doesn't actually have to be a base 2286 // type of the object type, in which case we just ignore it. 2287 // Otherwise build the appropriate casts. 2288 if (IsDerivedFrom(FromRecordType, QRecordType)) { 2289 CXXCastPath BasePath; 2290 if (CheckDerivedToBaseConversion(FromRecordType, QRecordType, 2291 FromLoc, FromRange, &BasePath)) 2292 return ExprError(); 2293 2294 if (PointerConversions) 2295 QType = Context.getPointerType(QType); 2296 From = ImpCastExprToType(From, QType, CK_UncheckedDerivedToBase, 2297 VK, &BasePath).take(); 2298 2299 FromType = QType; 2300 FromRecordType = QRecordType; 2301 2302 // If the qualifier type was the same as the destination type, 2303 // we're done. 2304 if (Context.hasSameUnqualifiedType(FromRecordType, DestRecordType)) 2305 return Owned(From); 2306 } 2307 } 2308 2309 bool IgnoreAccess = false; 2310 2311 // If we actually found the member through a using declaration, cast 2312 // down to the using declaration's type. 2313 // 2314 // Pointer equality is fine here because only one declaration of a 2315 // class ever has member declarations. 2316 if (FoundDecl->getDeclContext() != Member->getDeclContext()) { 2317 assert(isa<UsingShadowDecl>(FoundDecl)); 2318 QualType URecordType = Context.getTypeDeclType( 2319 cast<CXXRecordDecl>(FoundDecl->getDeclContext())); 2320 2321 // We only need to do this if the naming-class to declaring-class 2322 // conversion is non-trivial. 2323 if (!Context.hasSameUnqualifiedType(FromRecordType, URecordType)) { 2324 assert(IsDerivedFrom(FromRecordType, URecordType)); 2325 CXXCastPath BasePath; 2326 if (CheckDerivedToBaseConversion(FromRecordType, URecordType, 2327 FromLoc, FromRange, &BasePath)) 2328 return ExprError(); 2329 2330 QualType UType = URecordType; 2331 if (PointerConversions) 2332 UType = Context.getPointerType(UType); 2333 From = ImpCastExprToType(From, UType, CK_UncheckedDerivedToBase, 2334 VK, &BasePath).take(); 2335 FromType = UType; 2336 FromRecordType = URecordType; 2337 } 2338 2339 // We don't do access control for the conversion from the 2340 // declaring class to the true declaring class. 2341 IgnoreAccess = true; 2342 } 2343 2344 CXXCastPath BasePath; 2345 if (CheckDerivedToBaseConversion(FromRecordType, DestRecordType, 2346 FromLoc, FromRange, &BasePath, 2347 IgnoreAccess)) 2348 return ExprError(); 2349 2350 return ImpCastExprToType(From, DestType, CK_UncheckedDerivedToBase, 2351 VK, &BasePath); 2352} 2353 2354bool Sema::UseArgumentDependentLookup(const CXXScopeSpec &SS, 2355 const LookupResult &R, 2356 bool HasTrailingLParen) { 2357 // Only when used directly as the postfix-expression of a call. 2358 if (!HasTrailingLParen) 2359 return false; 2360 2361 // Never if a scope specifier was provided. 2362 if (SS.isSet()) 2363 return false; 2364 2365 // Only in C++ or ObjC++. 2366 if (!getLangOpts().CPlusPlus) 2367 return false; 2368 2369 // Turn off ADL when we find certain kinds of declarations during 2370 // normal lookup: 2371 for (LookupResult::iterator I = R.begin(), E = R.end(); I != E; ++I) { 2372 NamedDecl *D = *I; 2373 2374 // C++0x [basic.lookup.argdep]p3: 2375 // -- a declaration of a class member 2376 // Since using decls preserve this property, we check this on the 2377 // original decl. 2378 if (D->isCXXClassMember()) 2379 return false; 2380 2381 // C++0x [basic.lookup.argdep]p3: 2382 // -- a block-scope function declaration that is not a 2383 // using-declaration 2384 // NOTE: we also trigger this for function templates (in fact, we 2385 // don't check the decl type at all, since all other decl types 2386 // turn off ADL anyway). 2387 if (isa<UsingShadowDecl>(D)) 2388 D = cast<UsingShadowDecl>(D)->getTargetDecl(); 2389 else if (D->getDeclContext()->isFunctionOrMethod()) 2390 return false; 2391 2392 // C++0x [basic.lookup.argdep]p3: 2393 // -- a declaration that is neither a function or a function 2394 // template 2395 // And also for builtin functions. 2396 if (isa<FunctionDecl>(D)) { 2397 FunctionDecl *FDecl = cast<FunctionDecl>(D); 2398 2399 // But also builtin functions. 2400 if (FDecl->getBuiltinID() && FDecl->isImplicit()) 2401 return false; 2402 } else if (!isa<FunctionTemplateDecl>(D)) 2403 return false; 2404 } 2405 2406 return true; 2407} 2408 2409 2410/// Diagnoses obvious problems with the use of the given declaration 2411/// as an expression. This is only actually called for lookups that 2412/// were not overloaded, and it doesn't promise that the declaration 2413/// will in fact be used. 2414static bool CheckDeclInExpr(Sema &S, SourceLocation Loc, NamedDecl *D) { 2415 if (isa<TypedefNameDecl>(D)) { 2416 S.Diag(Loc, diag::err_unexpected_typedef) << D->getDeclName(); 2417 return true; 2418 } 2419 2420 if (isa<ObjCInterfaceDecl>(D)) { 2421 S.Diag(Loc, diag::err_unexpected_interface) << D->getDeclName(); 2422 return true; 2423 } 2424 2425 if (isa<NamespaceDecl>(D)) { 2426 S.Diag(Loc, diag::err_unexpected_namespace) << D->getDeclName(); 2427 return true; 2428 } 2429 2430 return false; 2431} 2432 2433ExprResult 2434Sema::BuildDeclarationNameExpr(const CXXScopeSpec &SS, 2435 LookupResult &R, 2436 bool NeedsADL) { 2437 // If this is a single, fully-resolved result and we don't need ADL, 2438 // just build an ordinary singleton decl ref. 2439 if (!NeedsADL && R.isSingleResult() && !R.getAsSingle<FunctionTemplateDecl>()) 2440 return BuildDeclarationNameExpr(SS, R.getLookupNameInfo(), R.getFoundDecl(), 2441 R.getRepresentativeDecl()); 2442 2443 // We only need to check the declaration if there's exactly one 2444 // result, because in the overloaded case the results can only be 2445 // functions and function templates. 2446 if (R.isSingleResult() && 2447 CheckDeclInExpr(*this, R.getNameLoc(), R.getFoundDecl())) 2448 return ExprError(); 2449 2450 // Otherwise, just build an unresolved lookup expression. Suppress 2451 // any lookup-related diagnostics; we'll hash these out later, when 2452 // we've picked a target. 2453 R.suppressDiagnostics(); 2454 2455 UnresolvedLookupExpr *ULE 2456 = UnresolvedLookupExpr::Create(Context, R.getNamingClass(), 2457 SS.getWithLocInContext(Context), 2458 R.getLookupNameInfo(), 2459 NeedsADL, R.isOverloadedResult(), 2460 R.begin(), R.end()); 2461 2462 return Owned(ULE); 2463} 2464 2465/// \brief Complete semantic analysis for a reference to the given declaration. 2466ExprResult 2467Sema::BuildDeclarationNameExpr(const CXXScopeSpec &SS, 2468 const DeclarationNameInfo &NameInfo, 2469 NamedDecl *D, NamedDecl *FoundD) { 2470 assert(D && "Cannot refer to a NULL declaration"); 2471 assert(!isa<FunctionTemplateDecl>(D) && 2472 "Cannot refer unambiguously to a function template"); 2473 2474 SourceLocation Loc = NameInfo.getLoc(); 2475 if (CheckDeclInExpr(*this, Loc, D)) 2476 return ExprError(); 2477 2478 if (TemplateDecl *Template = dyn_cast<TemplateDecl>(D)) { 2479 // Specifically diagnose references to class templates that are missing 2480 // a template argument list. 2481 Diag(Loc, diag::err_template_decl_ref) 2482 << Template << SS.getRange(); 2483 Diag(Template->getLocation(), diag::note_template_decl_here); 2484 return ExprError(); 2485 } 2486 2487 // Make sure that we're referring to a value. 2488 ValueDecl *VD = dyn_cast<ValueDecl>(D); 2489 if (!VD) { 2490 Diag(Loc, diag::err_ref_non_value) 2491 << D << SS.getRange(); 2492 Diag(D->getLocation(), diag::note_declared_at); 2493 return ExprError(); 2494 } 2495 2496 // Check whether this declaration can be used. Note that we suppress 2497 // this check when we're going to perform argument-dependent lookup 2498 // on this function name, because this might not be the function 2499 // that overload resolution actually selects. 2500 if (DiagnoseUseOfDecl(VD, Loc)) 2501 return ExprError(); 2502 2503 // Only create DeclRefExpr's for valid Decl's. 2504 if (VD->isInvalidDecl()) 2505 return ExprError(); 2506 2507 // Handle members of anonymous structs and unions. If we got here, 2508 // and the reference is to a class member indirect field, then this 2509 // must be the subject of a pointer-to-member expression. 2510 if (IndirectFieldDecl *indirectField = dyn_cast<IndirectFieldDecl>(VD)) 2511 if (!indirectField->isCXXClassMember()) 2512 return BuildAnonymousStructUnionMemberReference(SS, NameInfo.getLoc(), 2513 indirectField); 2514 2515 { 2516 QualType type = VD->getType(); 2517 ExprValueKind valueKind = VK_RValue; 2518 2519 switch (D->getKind()) { 2520 // Ignore all the non-ValueDecl kinds. 2521#define ABSTRACT_DECL(kind) 2522#define VALUE(type, base) 2523#define DECL(type, base) \ 2524 case Decl::type: 2525#include "clang/AST/DeclNodes.inc" 2526 llvm_unreachable("invalid value decl kind"); 2527 2528 // These shouldn't make it here. 2529 case Decl::ObjCAtDefsField: 2530 case Decl::ObjCIvar: 2531 llvm_unreachable("forming non-member reference to ivar?"); 2532 2533 // Enum constants are always r-values and never references. 2534 // Unresolved using declarations are dependent. 2535 case Decl::EnumConstant: 2536 case Decl::UnresolvedUsingValue: 2537 valueKind = VK_RValue; 2538 break; 2539 2540 // Fields and indirect fields that got here must be for 2541 // pointer-to-member expressions; we just call them l-values for 2542 // internal consistency, because this subexpression doesn't really 2543 // exist in the high-level semantics. 2544 case Decl::Field: 2545 case Decl::IndirectField: 2546 assert(getLangOpts().CPlusPlus && 2547 "building reference to field in C?"); 2548 2549 // These can't have reference type in well-formed programs, but 2550 // for internal consistency we do this anyway. 2551 type = type.getNonReferenceType(); 2552 valueKind = VK_LValue; 2553 break; 2554 2555 // Non-type template parameters are either l-values or r-values 2556 // depending on the type. 2557 case Decl::NonTypeTemplateParm: { 2558 if (const ReferenceType *reftype = type->getAs<ReferenceType>()) { 2559 type = reftype->getPointeeType(); 2560 valueKind = VK_LValue; // even if the parameter is an r-value reference 2561 break; 2562 } 2563 2564 // For non-references, we need to strip qualifiers just in case 2565 // the template parameter was declared as 'const int' or whatever. 2566 valueKind = VK_RValue; 2567 type = type.getUnqualifiedType(); 2568 break; 2569 } 2570 2571 case Decl::Var: 2572 // In C, "extern void blah;" is valid and is an r-value. 2573 if (!getLangOpts().CPlusPlus && 2574 !type.hasQualifiers() && 2575 type->isVoidType()) { 2576 valueKind = VK_RValue; 2577 break; 2578 } 2579 // fallthrough 2580 2581 case Decl::ImplicitParam: 2582 case Decl::ParmVar: { 2583 // These are always l-values. 2584 valueKind = VK_LValue; 2585 type = type.getNonReferenceType(); 2586 2587 // FIXME: Does the addition of const really only apply in 2588 // potentially-evaluated contexts? Since the variable isn't actually 2589 // captured in an unevaluated context, it seems that the answer is no. 2590 if (!isUnevaluatedContext()) { 2591 QualType CapturedType = getCapturedDeclRefType(cast<VarDecl>(VD), Loc); 2592 if (!CapturedType.isNull()) 2593 type = CapturedType; 2594 } 2595 2596 break; 2597 } 2598 2599 case Decl::Function: { 2600 if (unsigned BID = cast<FunctionDecl>(VD)->getBuiltinID()) { 2601 if (!Context.BuiltinInfo.isPredefinedLibFunction(BID)) { 2602 type = Context.BuiltinFnTy; 2603 valueKind = VK_RValue; 2604 break; 2605 } 2606 } 2607 2608 const FunctionType *fty = type->castAs<FunctionType>(); 2609 2610 // If we're referring to a function with an __unknown_anytype 2611 // result type, make the entire expression __unknown_anytype. 2612 if (fty->getResultType() == Context.UnknownAnyTy) { 2613 type = Context.UnknownAnyTy; 2614 valueKind = VK_RValue; 2615 break; 2616 } 2617 2618 // Functions are l-values in C++. 2619 if (getLangOpts().CPlusPlus) { 2620 valueKind = VK_LValue; 2621 break; 2622 } 2623 2624 // C99 DR 316 says that, if a function type comes from a 2625 // function definition (without a prototype), that type is only 2626 // used for checking compatibility. Therefore, when referencing 2627 // the function, we pretend that we don't have the full function 2628 // type. 2629 if (!cast<FunctionDecl>(VD)->hasPrototype() && 2630 isa<FunctionProtoType>(fty)) 2631 type = Context.getFunctionNoProtoType(fty->getResultType(), 2632 fty->getExtInfo()); 2633 2634 // Functions are r-values in C. 2635 valueKind = VK_RValue; 2636 break; 2637 } 2638 2639 case Decl::CXXMethod: 2640 // If we're referring to a method with an __unknown_anytype 2641 // result type, make the entire expression __unknown_anytype. 2642 // This should only be possible with a type written directly. 2643 if (const FunctionProtoType *proto 2644 = dyn_cast<FunctionProtoType>(VD->getType())) 2645 if (proto->getResultType() == Context.UnknownAnyTy) { 2646 type = Context.UnknownAnyTy; 2647 valueKind = VK_RValue; 2648 break; 2649 } 2650 2651 // C++ methods are l-values if static, r-values if non-static. 2652 if (cast<CXXMethodDecl>(VD)->isStatic()) { 2653 valueKind = VK_LValue; 2654 break; 2655 } 2656 // fallthrough 2657 2658 case Decl::CXXConversion: 2659 case Decl::CXXDestructor: 2660 case Decl::CXXConstructor: 2661 valueKind = VK_RValue; 2662 break; 2663 } 2664 2665 return BuildDeclRefExpr(VD, type, valueKind, NameInfo, &SS, FoundD); 2666 } 2667} 2668 2669ExprResult Sema::ActOnPredefinedExpr(SourceLocation Loc, tok::TokenKind Kind) { 2670 PredefinedExpr::IdentType IT; 2671 2672 switch (Kind) { 2673 default: llvm_unreachable("Unknown simple primary expr!"); 2674 case tok::kw___func__: IT = PredefinedExpr::Func; break; // [C99 6.4.2.2] 2675 case tok::kw___FUNCTION__: IT = PredefinedExpr::Function; break; 2676 case tok::kw_L__FUNCTION__: IT = PredefinedExpr::LFunction; break; 2677 case tok::kw___PRETTY_FUNCTION__: IT = PredefinedExpr::PrettyFunction; break; 2678 } 2679 2680 // Pre-defined identifiers are of type char[x], where x is the length of the 2681 // string. 2682 2683 Decl *currentDecl = getCurFunctionOrMethodDecl(); 2684 // Blocks and lambdas can occur at global scope. Don't emit a warning. 2685 if (!currentDecl) { 2686 if (const BlockScopeInfo *BSI = getCurBlock()) 2687 currentDecl = BSI->TheDecl; 2688 else if (const LambdaScopeInfo *LSI = getCurLambda()) 2689 currentDecl = LSI->CallOperator; 2690 } 2691 2692 if (!currentDecl) { 2693 Diag(Loc, diag::ext_predef_outside_function); 2694 currentDecl = Context.getTranslationUnitDecl(); 2695 } 2696 2697 QualType ResTy; 2698 if (cast<DeclContext>(currentDecl)->isDependentContext()) { 2699 ResTy = Context.DependentTy; 2700 } else { 2701 unsigned Length = PredefinedExpr::ComputeName(IT, currentDecl).length(); 2702 2703 llvm::APInt LengthI(32, Length + 1); 2704 if (IT == PredefinedExpr::LFunction) 2705 ResTy = Context.WCharTy.withConst(); 2706 else 2707 ResTy = Context.CharTy.withConst(); 2708 ResTy = Context.getConstantArrayType(ResTy, LengthI, ArrayType::Normal, 0); 2709 } 2710 return Owned(new (Context) PredefinedExpr(Loc, ResTy, IT)); 2711} 2712 2713ExprResult Sema::ActOnCharacterConstant(const Token &Tok, Scope *UDLScope) { 2714 SmallString<16> CharBuffer; 2715 bool Invalid = false; 2716 StringRef ThisTok = PP.getSpelling(Tok, CharBuffer, &Invalid); 2717 if (Invalid) 2718 return ExprError(); 2719 2720 CharLiteralParser Literal(ThisTok.begin(), ThisTok.end(), Tok.getLocation(), 2721 PP, Tok.getKind()); 2722 if (Literal.hadError()) 2723 return ExprError(); 2724 2725 QualType Ty; 2726 if (Literal.isWide()) 2727 Ty = Context.WCharTy; // L'x' -> wchar_t in C and C++. 2728 else if (Literal.isUTF16()) 2729 Ty = Context.Char16Ty; // u'x' -> char16_t in C11 and C++11. 2730 else if (Literal.isUTF32()) 2731 Ty = Context.Char32Ty; // U'x' -> char32_t in C11 and C++11. 2732 else if (!getLangOpts().CPlusPlus || Literal.isMultiChar()) 2733 Ty = Context.IntTy; // 'x' -> int in C, 'wxyz' -> int in C++. 2734 else 2735 Ty = Context.CharTy; // 'x' -> char in C++ 2736 2737 CharacterLiteral::CharacterKind Kind = CharacterLiteral::Ascii; 2738 if (Literal.isWide()) 2739 Kind = CharacterLiteral::Wide; 2740 else if (Literal.isUTF16()) 2741 Kind = CharacterLiteral::UTF16; 2742 else if (Literal.isUTF32()) 2743 Kind = CharacterLiteral::UTF32; 2744 2745 Expr *Lit = new (Context) CharacterLiteral(Literal.getValue(), Kind, Ty, 2746 Tok.getLocation()); 2747 2748 if (Literal.getUDSuffix().empty()) 2749 return Owned(Lit); 2750 2751 // We're building a user-defined literal. 2752 IdentifierInfo *UDSuffix = &Context.Idents.get(Literal.getUDSuffix()); 2753 SourceLocation UDSuffixLoc = 2754 getUDSuffixLoc(*this, Tok.getLocation(), Literal.getUDSuffixOffset()); 2755 2756 // Make sure we're allowed user-defined literals here. 2757 if (!UDLScope) 2758 return ExprError(Diag(UDSuffixLoc, diag::err_invalid_character_udl)); 2759 2760 // C++11 [lex.ext]p6: The literal L is treated as a call of the form 2761 // operator "" X (ch) 2762 return BuildCookedLiteralOperatorCall(*this, UDLScope, UDSuffix, UDSuffixLoc, 2763 llvm::makeArrayRef(&Lit, 1), 2764 Tok.getLocation()); 2765} 2766 2767ExprResult Sema::ActOnIntegerConstant(SourceLocation Loc, uint64_t Val) { 2768 unsigned IntSize = Context.getTargetInfo().getIntWidth(); 2769 return Owned(IntegerLiteral::Create(Context, llvm::APInt(IntSize, Val), 2770 Context.IntTy, Loc)); 2771} 2772 2773static Expr *BuildFloatingLiteral(Sema &S, NumericLiteralParser &Literal, 2774 QualType Ty, SourceLocation Loc) { 2775 const llvm::fltSemantics &Format = S.Context.getFloatTypeSemantics(Ty); 2776 2777 using llvm::APFloat; 2778 APFloat Val(Format); 2779 2780 APFloat::opStatus result = Literal.GetFloatValue(Val); 2781 2782 // Overflow is always an error, but underflow is only an error if 2783 // we underflowed to zero (APFloat reports denormals as underflow). 2784 if ((result & APFloat::opOverflow) || 2785 ((result & APFloat::opUnderflow) && Val.isZero())) { 2786 unsigned diagnostic; 2787 SmallString<20> buffer; 2788 if (result & APFloat::opOverflow) { 2789 diagnostic = diag::warn_float_overflow; 2790 APFloat::getLargest(Format).toString(buffer); 2791 } else { 2792 diagnostic = diag::warn_float_underflow; 2793 APFloat::getSmallest(Format).toString(buffer); 2794 } 2795 2796 S.Diag(Loc, diagnostic) 2797 << Ty 2798 << StringRef(buffer.data(), buffer.size()); 2799 } 2800 2801 bool isExact = (result == APFloat::opOK); 2802 return FloatingLiteral::Create(S.Context, Val, isExact, Ty, Loc); 2803} 2804 2805ExprResult Sema::ActOnNumericConstant(const Token &Tok, Scope *UDLScope) { 2806 // Fast path for a single digit (which is quite common). A single digit 2807 // cannot have a trigraph, escaped newline, radix prefix, or suffix. 2808 if (Tok.getLength() == 1) { 2809 const char Val = PP.getSpellingOfSingleCharacterNumericConstant(Tok); 2810 return ActOnIntegerConstant(Tok.getLocation(), Val-'0'); 2811 } 2812 2813 SmallString<128> SpellingBuffer; 2814 // NumericLiteralParser wants to overread by one character. Add padding to 2815 // the buffer in case the token is copied to the buffer. If getSpelling() 2816 // returns a StringRef to the memory buffer, it should have a null char at 2817 // the EOF, so it is also safe. 2818 SpellingBuffer.resize(Tok.getLength() + 1); 2819 2820 // Get the spelling of the token, which eliminates trigraphs, etc. 2821 bool Invalid = false; 2822 StringRef TokSpelling = PP.getSpelling(Tok, SpellingBuffer, &Invalid); 2823 if (Invalid) 2824 return ExprError(); 2825 2826 NumericLiteralParser Literal(TokSpelling, Tok.getLocation(), PP); 2827 if (Literal.hadError) 2828 return ExprError(); 2829 2830 if (Literal.hasUDSuffix()) { 2831 // We're building a user-defined literal. 2832 IdentifierInfo *UDSuffix = &Context.Idents.get(Literal.getUDSuffix()); 2833 SourceLocation UDSuffixLoc = 2834 getUDSuffixLoc(*this, Tok.getLocation(), Literal.getUDSuffixOffset()); 2835 2836 // Make sure we're allowed user-defined literals here. 2837 if (!UDLScope) 2838 return ExprError(Diag(UDSuffixLoc, diag::err_invalid_numeric_udl)); 2839 2840 QualType CookedTy; 2841 if (Literal.isFloatingLiteral()) { 2842 // C++11 [lex.ext]p4: If S contains a literal operator with parameter type 2843 // long double, the literal is treated as a call of the form 2844 // operator "" X (f L) 2845 CookedTy = Context.LongDoubleTy; 2846 } else { 2847 // C++11 [lex.ext]p3: If S contains a literal operator with parameter type 2848 // unsigned long long, the literal is treated as a call of the form 2849 // operator "" X (n ULL) 2850 CookedTy = Context.UnsignedLongLongTy; 2851 } 2852 2853 DeclarationName OpName = 2854 Context.DeclarationNames.getCXXLiteralOperatorName(UDSuffix); 2855 DeclarationNameInfo OpNameInfo(OpName, UDSuffixLoc); 2856 OpNameInfo.setCXXLiteralOperatorNameLoc(UDSuffixLoc); 2857 2858 // Perform literal operator lookup to determine if we're building a raw 2859 // literal or a cooked one. 2860 LookupResult R(*this, OpName, UDSuffixLoc, LookupOrdinaryName); 2861 switch (LookupLiteralOperator(UDLScope, R, llvm::makeArrayRef(&CookedTy, 1), 2862 /*AllowRawAndTemplate*/true)) { 2863 case LOLR_Error: 2864 return ExprError(); 2865 2866 case LOLR_Cooked: { 2867 Expr *Lit; 2868 if (Literal.isFloatingLiteral()) { 2869 Lit = BuildFloatingLiteral(*this, Literal, CookedTy, Tok.getLocation()); 2870 } else { 2871 llvm::APInt ResultVal(Context.getTargetInfo().getLongLongWidth(), 0); 2872 if (Literal.GetIntegerValue(ResultVal)) 2873 Diag(Tok.getLocation(), diag::warn_integer_too_large); 2874 Lit = IntegerLiteral::Create(Context, ResultVal, CookedTy, 2875 Tok.getLocation()); 2876 } 2877 return BuildLiteralOperatorCall(R, OpNameInfo, 2878 llvm::makeArrayRef(&Lit, 1), 2879 Tok.getLocation()); 2880 } 2881 2882 case LOLR_Raw: { 2883 // C++11 [lit.ext]p3, p4: If S contains a raw literal operator, the 2884 // literal is treated as a call of the form 2885 // operator "" X ("n") 2886 SourceLocation TokLoc = Tok.getLocation(); 2887 unsigned Length = Literal.getUDSuffixOffset(); 2888 QualType StrTy = Context.getConstantArrayType( 2889 Context.CharTy.withConst(), llvm::APInt(32, Length + 1), 2890 ArrayType::Normal, 0); 2891 Expr *Lit = StringLiteral::Create( 2892 Context, StringRef(TokSpelling.data(), Length), StringLiteral::Ascii, 2893 /*Pascal*/false, StrTy, &TokLoc, 1); 2894 return BuildLiteralOperatorCall(R, OpNameInfo, 2895 llvm::makeArrayRef(&Lit, 1), TokLoc); 2896 } 2897 2898 case LOLR_Template: 2899 // C++11 [lit.ext]p3, p4: Otherwise (S contains a literal operator 2900 // template), L is treated as a call fo the form 2901 // operator "" X <'c1', 'c2', ... 'ck'>() 2902 // where n is the source character sequence c1 c2 ... ck. 2903 TemplateArgumentListInfo ExplicitArgs; 2904 unsigned CharBits = Context.getIntWidth(Context.CharTy); 2905 bool CharIsUnsigned = Context.CharTy->isUnsignedIntegerType(); 2906 llvm::APSInt Value(CharBits, CharIsUnsigned); 2907 for (unsigned I = 0, N = Literal.getUDSuffixOffset(); I != N; ++I) { 2908 Value = TokSpelling[I]; 2909 TemplateArgument Arg(Context, Value, Context.CharTy); 2910 TemplateArgumentLocInfo ArgInfo; 2911 ExplicitArgs.addArgument(TemplateArgumentLoc(Arg, ArgInfo)); 2912 } 2913 return BuildLiteralOperatorCall(R, OpNameInfo, ArrayRef<Expr*>(), 2914 Tok.getLocation(), &ExplicitArgs); 2915 } 2916 2917 llvm_unreachable("unexpected literal operator lookup result"); 2918 } 2919 2920 Expr *Res; 2921 2922 if (Literal.isFloatingLiteral()) { 2923 QualType Ty; 2924 if (Literal.isFloat) 2925 Ty = Context.FloatTy; 2926 else if (!Literal.isLong) 2927 Ty = Context.DoubleTy; 2928 else 2929 Ty = Context.LongDoubleTy; 2930 2931 Res = BuildFloatingLiteral(*this, Literal, Ty, Tok.getLocation()); 2932 2933 if (Ty == Context.DoubleTy) { 2934 if (getLangOpts().SinglePrecisionConstants) { 2935 Res = ImpCastExprToType(Res, Context.FloatTy, CK_FloatingCast).take(); 2936 } else if (getLangOpts().OpenCL && !getOpenCLOptions().cl_khr_fp64) { 2937 Diag(Tok.getLocation(), diag::warn_double_const_requires_fp64); 2938 Res = ImpCastExprToType(Res, Context.FloatTy, CK_FloatingCast).take(); 2939 } 2940 } 2941 } else if (!Literal.isIntegerLiteral()) { 2942 return ExprError(); 2943 } else { 2944 QualType Ty; 2945 2946 // 'long long' is a C99 or C++11 feature. 2947 if (!getLangOpts().C99 && Literal.isLongLong) { 2948 if (getLangOpts().CPlusPlus) 2949 Diag(Tok.getLocation(), 2950 getLangOpts().CPlusPlus11 ? 2951 diag::warn_cxx98_compat_longlong : diag::ext_cxx11_longlong); 2952 else 2953 Diag(Tok.getLocation(), diag::ext_c99_longlong); 2954 } 2955 2956 // Get the value in the widest-possible width. 2957 unsigned MaxWidth = Context.getTargetInfo().getIntMaxTWidth(); 2958 // The microsoft literal suffix extensions support 128-bit literals, which 2959 // may be wider than [u]intmax_t. 2960 // FIXME: Actually, they don't. We seem to have accidentally invented the 2961 // i128 suffix. 2962 if (Literal.isMicrosoftInteger && MaxWidth < 128 && 2963 PP.getTargetInfo().hasInt128Type()) 2964 MaxWidth = 128; 2965 llvm::APInt ResultVal(MaxWidth, 0); 2966 2967 if (Literal.GetIntegerValue(ResultVal)) { 2968 // If this value didn't fit into uintmax_t, warn and force to ull. 2969 Diag(Tok.getLocation(), diag::warn_integer_too_large); 2970 Ty = Context.UnsignedLongLongTy; 2971 assert(Context.getTypeSize(Ty) == ResultVal.getBitWidth() && 2972 "long long is not intmax_t?"); 2973 } else { 2974 // If this value fits into a ULL, try to figure out what else it fits into 2975 // according to the rules of C99 6.4.4.1p5. 2976 2977 // Octal, Hexadecimal, and integers with a U suffix are allowed to 2978 // be an unsigned int. 2979 bool AllowUnsigned = Literal.isUnsigned || Literal.getRadix() != 10; 2980 2981 // Check from smallest to largest, picking the smallest type we can. 2982 unsigned Width = 0; 2983 if (!Literal.isLong && !Literal.isLongLong) { 2984 // Are int/unsigned possibilities? 2985 unsigned IntSize = Context.getTargetInfo().getIntWidth(); 2986 2987 // Does it fit in a unsigned int? 2988 if (ResultVal.isIntN(IntSize)) { 2989 // Does it fit in a signed int? 2990 if (!Literal.isUnsigned && ResultVal[IntSize-1] == 0) 2991 Ty = Context.IntTy; 2992 else if (AllowUnsigned) 2993 Ty = Context.UnsignedIntTy; 2994 Width = IntSize; 2995 } 2996 } 2997 2998 // Are long/unsigned long possibilities? 2999 if (Ty.isNull() && !Literal.isLongLong) { 3000 unsigned LongSize = Context.getTargetInfo().getLongWidth(); 3001 3002 // Does it fit in a unsigned long? 3003 if (ResultVal.isIntN(LongSize)) { 3004 // Does it fit in a signed long? 3005 if (!Literal.isUnsigned && ResultVal[LongSize-1] == 0) 3006 Ty = Context.LongTy; 3007 else if (AllowUnsigned) 3008 Ty = Context.UnsignedLongTy; 3009 Width = LongSize; 3010 } 3011 } 3012 3013 // Check long long if needed. 3014 if (Ty.isNull()) { 3015 unsigned LongLongSize = Context.getTargetInfo().getLongLongWidth(); 3016 3017 // Does it fit in a unsigned long long? 3018 if (ResultVal.isIntN(LongLongSize)) { 3019 // Does it fit in a signed long long? 3020 // To be compatible with MSVC, hex integer literals ending with the 3021 // LL or i64 suffix are always signed in Microsoft mode. 3022 if (!Literal.isUnsigned && (ResultVal[LongLongSize-1] == 0 || 3023 (getLangOpts().MicrosoftExt && Literal.isLongLong))) 3024 Ty = Context.LongLongTy; 3025 else if (AllowUnsigned) 3026 Ty = Context.UnsignedLongLongTy; 3027 Width = LongLongSize; 3028 } 3029 } 3030 3031 // If it doesn't fit in unsigned long long, and we're using Microsoft 3032 // extensions, then its a 128-bit integer literal. 3033 if (Ty.isNull() && Literal.isMicrosoftInteger && 3034 PP.getTargetInfo().hasInt128Type()) { 3035 if (Literal.isUnsigned) 3036 Ty = Context.UnsignedInt128Ty; 3037 else 3038 Ty = Context.Int128Ty; 3039 Width = 128; 3040 } 3041 3042 // If we still couldn't decide a type, we probably have something that 3043 // does not fit in a signed long long, but has no U suffix. 3044 if (Ty.isNull()) { 3045 Diag(Tok.getLocation(), diag::warn_integer_too_large_for_signed); 3046 Ty = Context.UnsignedLongLongTy; 3047 Width = Context.getTargetInfo().getLongLongWidth(); 3048 } 3049 3050 if (ResultVal.getBitWidth() != Width) 3051 ResultVal = ResultVal.trunc(Width); 3052 } 3053 Res = IntegerLiteral::Create(Context, ResultVal, Ty, Tok.getLocation()); 3054 } 3055 3056 // If this is an imaginary literal, create the ImaginaryLiteral wrapper. 3057 if (Literal.isImaginary) 3058 Res = new (Context) ImaginaryLiteral(Res, 3059 Context.getComplexType(Res->getType())); 3060 3061 return Owned(Res); 3062} 3063 3064ExprResult Sema::ActOnParenExpr(SourceLocation L, SourceLocation R, Expr *E) { 3065 assert((E != 0) && "ActOnParenExpr() missing expr"); 3066 return Owned(new (Context) ParenExpr(L, R, E)); 3067} 3068 3069static bool CheckVecStepTraitOperandType(Sema &S, QualType T, 3070 SourceLocation Loc, 3071 SourceRange ArgRange) { 3072 // [OpenCL 1.1 6.11.12] "The vec_step built-in function takes a built-in 3073 // scalar or vector data type argument..." 3074 // Every built-in scalar type (OpenCL 1.1 6.1.1) is either an arithmetic 3075 // type (C99 6.2.5p18) or void. 3076 if (!(T->isArithmeticType() || T->isVoidType() || T->isVectorType())) { 3077 S.Diag(Loc, diag::err_vecstep_non_scalar_vector_type) 3078 << T << ArgRange; 3079 return true; 3080 } 3081 3082 assert((T->isVoidType() || !T->isIncompleteType()) && 3083 "Scalar types should always be complete"); 3084 return false; 3085} 3086 3087static bool CheckExtensionTraitOperandType(Sema &S, QualType T, 3088 SourceLocation Loc, 3089 SourceRange ArgRange, 3090 UnaryExprOrTypeTrait TraitKind) { 3091 // C99 6.5.3.4p1: 3092 if (T->isFunctionType() && 3093 (TraitKind == UETT_SizeOf || TraitKind == UETT_AlignOf)) { 3094 // sizeof(function)/alignof(function) is allowed as an extension. 3095 S.Diag(Loc, diag::ext_sizeof_alignof_function_type) 3096 << TraitKind << ArgRange; 3097 return false; 3098 } 3099 3100 // Allow sizeof(void)/alignof(void) as an extension. 3101 if (T->isVoidType()) { 3102 S.Diag(Loc, diag::ext_sizeof_alignof_void_type) << TraitKind << ArgRange; 3103 return false; 3104 } 3105 3106 return true; 3107} 3108 3109static bool CheckObjCTraitOperandConstraints(Sema &S, QualType T, 3110 SourceLocation Loc, 3111 SourceRange ArgRange, 3112 UnaryExprOrTypeTrait TraitKind) { 3113 // Reject sizeof(interface) and sizeof(interface<proto>) if the 3114 // runtime doesn't allow it. 3115 if (!S.LangOpts.ObjCRuntime.allowsSizeofAlignof() && T->isObjCObjectType()) { 3116 S.Diag(Loc, diag::err_sizeof_nonfragile_interface) 3117 << T << (TraitKind == UETT_SizeOf) 3118 << ArgRange; 3119 return true; 3120 } 3121 3122 return false; 3123} 3124 3125/// \brief Check whether E is a pointer from a decayed array type (the decayed 3126/// pointer type is equal to T) and emit a warning if it is. 3127static void warnOnSizeofOnArrayDecay(Sema &S, SourceLocation Loc, QualType T, 3128 Expr *E) { 3129 // Don't warn if the operation changed the type. 3130 if (T != E->getType()) 3131 return; 3132 3133 // Now look for array decays. 3134 ImplicitCastExpr *ICE = dyn_cast<ImplicitCastExpr>(E); 3135 if (!ICE || ICE->getCastKind() != CK_ArrayToPointerDecay) 3136 return; 3137 3138 S.Diag(Loc, diag::warn_sizeof_array_decay) << ICE->getSourceRange() 3139 << ICE->getType() 3140 << ICE->getSubExpr()->getType(); 3141} 3142 3143/// \brief Check the constrains on expression operands to unary type expression 3144/// and type traits. 3145/// 3146/// Completes any types necessary and validates the constraints on the operand 3147/// expression. The logic mostly mirrors the type-based overload, but may modify 3148/// the expression as it completes the type for that expression through template 3149/// instantiation, etc. 3150bool Sema::CheckUnaryExprOrTypeTraitOperand(Expr *E, 3151 UnaryExprOrTypeTrait ExprKind) { 3152 QualType ExprTy = E->getType(); 3153 3154 // C++ [expr.sizeof]p2: "When applied to a reference or a reference type, 3155 // the result is the size of the referenced type." 3156 // C++ [expr.alignof]p3: "When alignof is applied to a reference type, the 3157 // result shall be the alignment of the referenced type." 3158 if (const ReferenceType *Ref = ExprTy->getAs<ReferenceType>()) 3159 ExprTy = Ref->getPointeeType(); 3160 3161 if (ExprKind == UETT_VecStep) 3162 return CheckVecStepTraitOperandType(*this, ExprTy, E->getExprLoc(), 3163 E->getSourceRange()); 3164 3165 // Whitelist some types as extensions 3166 if (!CheckExtensionTraitOperandType(*this, ExprTy, E->getExprLoc(), 3167 E->getSourceRange(), ExprKind)) 3168 return false; 3169 3170 if (RequireCompleteExprType(E, 3171 diag::err_sizeof_alignof_incomplete_type, 3172 ExprKind, E->getSourceRange())) 3173 return true; 3174 3175 // Completeing the expression's type may have changed it. 3176 ExprTy = E->getType(); 3177 if (const ReferenceType *Ref = ExprTy->getAs<ReferenceType>()) 3178 ExprTy = Ref->getPointeeType(); 3179 3180 if (CheckObjCTraitOperandConstraints(*this, ExprTy, E->getExprLoc(), 3181 E->getSourceRange(), ExprKind)) 3182 return true; 3183 3184 if (ExprKind == UETT_SizeOf) { 3185 if (DeclRefExpr *DeclRef = dyn_cast<DeclRefExpr>(E->IgnoreParens())) { 3186 if (ParmVarDecl *PVD = dyn_cast<ParmVarDecl>(DeclRef->getFoundDecl())) { 3187 QualType OType = PVD->getOriginalType(); 3188 QualType Type = PVD->getType(); 3189 if (Type->isPointerType() && OType->isArrayType()) { 3190 Diag(E->getExprLoc(), diag::warn_sizeof_array_param) 3191 << Type << OType; 3192 Diag(PVD->getLocation(), diag::note_declared_at); 3193 } 3194 } 3195 } 3196 3197 // Warn on "sizeof(array op x)" and "sizeof(x op array)", where the array 3198 // decays into a pointer and returns an unintended result. This is most 3199 // likely a typo for "sizeof(array) op x". 3200 if (BinaryOperator *BO = dyn_cast<BinaryOperator>(E->IgnoreParens())) { 3201 warnOnSizeofOnArrayDecay(*this, BO->getOperatorLoc(), BO->getType(), 3202 BO->getLHS()); 3203 warnOnSizeofOnArrayDecay(*this, BO->getOperatorLoc(), BO->getType(), 3204 BO->getRHS()); 3205 } 3206 } 3207 3208 return false; 3209} 3210 3211/// \brief Check the constraints on operands to unary expression and type 3212/// traits. 3213/// 3214/// This will complete any types necessary, and validate the various constraints 3215/// on those operands. 3216/// 3217/// The UsualUnaryConversions() function is *not* called by this routine. 3218/// C99 6.3.2.1p[2-4] all state: 3219/// Except when it is the operand of the sizeof operator ... 3220/// 3221/// C++ [expr.sizeof]p4 3222/// The lvalue-to-rvalue, array-to-pointer, and function-to-pointer 3223/// standard conversions are not applied to the operand of sizeof. 3224/// 3225/// This policy is followed for all of the unary trait expressions. 3226bool Sema::CheckUnaryExprOrTypeTraitOperand(QualType ExprType, 3227 SourceLocation OpLoc, 3228 SourceRange ExprRange, 3229 UnaryExprOrTypeTrait ExprKind) { 3230 if (ExprType->isDependentType()) 3231 return false; 3232 3233 // C++ [expr.sizeof]p2: "When applied to a reference or a reference type, 3234 // the result is the size of the referenced type." 3235 // C++ [expr.alignof]p3: "When alignof is applied to a reference type, the 3236 // result shall be the alignment of the referenced type." 3237 if (const ReferenceType *Ref = ExprType->getAs<ReferenceType>()) 3238 ExprType = Ref->getPointeeType(); 3239 3240 if (ExprKind == UETT_VecStep) 3241 return CheckVecStepTraitOperandType(*this, ExprType, OpLoc, ExprRange); 3242 3243 // Whitelist some types as extensions 3244 if (!CheckExtensionTraitOperandType(*this, ExprType, OpLoc, ExprRange, 3245 ExprKind)) 3246 return false; 3247 3248 if (RequireCompleteType(OpLoc, ExprType, 3249 diag::err_sizeof_alignof_incomplete_type, 3250 ExprKind, ExprRange)) 3251 return true; 3252 3253 if (CheckObjCTraitOperandConstraints(*this, ExprType, OpLoc, ExprRange, 3254 ExprKind)) 3255 return true; 3256 3257 return false; 3258} 3259 3260static bool CheckAlignOfExpr(Sema &S, Expr *E) { 3261 E = E->IgnoreParens(); 3262 3263 // alignof decl is always ok. 3264 if (isa<DeclRefExpr>(E)) 3265 return false; 3266 3267 // Cannot know anything else if the expression is dependent. 3268 if (E->isTypeDependent()) 3269 return false; 3270 3271 if (E->getBitField()) { 3272 S.Diag(E->getExprLoc(), diag::err_sizeof_alignof_bitfield) 3273 << 1 << E->getSourceRange(); 3274 return true; 3275 } 3276 3277 // Alignment of a field access is always okay, so long as it isn't a 3278 // bit-field. 3279 if (MemberExpr *ME = dyn_cast<MemberExpr>(E)) 3280 if (isa<FieldDecl>(ME->getMemberDecl())) 3281 return false; 3282 3283 return S.CheckUnaryExprOrTypeTraitOperand(E, UETT_AlignOf); 3284} 3285 3286bool Sema::CheckVecStepExpr(Expr *E) { 3287 E = E->IgnoreParens(); 3288 3289 // Cannot know anything else if the expression is dependent. 3290 if (E->isTypeDependent()) 3291 return false; 3292 3293 return CheckUnaryExprOrTypeTraitOperand(E, UETT_VecStep); 3294} 3295 3296/// \brief Build a sizeof or alignof expression given a type operand. 3297ExprResult 3298Sema::CreateUnaryExprOrTypeTraitExpr(TypeSourceInfo *TInfo, 3299 SourceLocation OpLoc, 3300 UnaryExprOrTypeTrait ExprKind, 3301 SourceRange R) { 3302 if (!TInfo) 3303 return ExprError(); 3304 3305 QualType T = TInfo->getType(); 3306 3307 if (!T->isDependentType() && 3308 CheckUnaryExprOrTypeTraitOperand(T, OpLoc, R, ExprKind)) 3309 return ExprError(); 3310 3311 // C99 6.5.3.4p4: the type (an unsigned integer type) is size_t. 3312 return Owned(new (Context) UnaryExprOrTypeTraitExpr(ExprKind, TInfo, 3313 Context.getSizeType(), 3314 OpLoc, R.getEnd())); 3315} 3316 3317/// \brief Build a sizeof or alignof expression given an expression 3318/// operand. 3319ExprResult 3320Sema::CreateUnaryExprOrTypeTraitExpr(Expr *E, SourceLocation OpLoc, 3321 UnaryExprOrTypeTrait ExprKind) { 3322 ExprResult PE = CheckPlaceholderExpr(E); 3323 if (PE.isInvalid()) 3324 return ExprError(); 3325 3326 E = PE.get(); 3327 3328 // Verify that the operand is valid. 3329 bool isInvalid = false; 3330 if (E->isTypeDependent()) { 3331 // Delay type-checking for type-dependent expressions. 3332 } else if (ExprKind == UETT_AlignOf) { 3333 isInvalid = CheckAlignOfExpr(*this, E); 3334 } else if (ExprKind == UETT_VecStep) { 3335 isInvalid = CheckVecStepExpr(E); 3336 } else if (E->getBitField()) { // C99 6.5.3.4p1. 3337 Diag(E->getExprLoc(), diag::err_sizeof_alignof_bitfield) << 0; 3338 isInvalid = true; 3339 } else { 3340 isInvalid = CheckUnaryExprOrTypeTraitOperand(E, UETT_SizeOf); 3341 } 3342 3343 if (isInvalid) 3344 return ExprError(); 3345 3346 if (ExprKind == UETT_SizeOf && E->getType()->isVariableArrayType()) { 3347 PE = TransformToPotentiallyEvaluated(E); 3348 if (PE.isInvalid()) return ExprError(); 3349 E = PE.take(); 3350 } 3351 3352 // C99 6.5.3.4p4: the type (an unsigned integer type) is size_t. 3353 return Owned(new (Context) UnaryExprOrTypeTraitExpr( 3354 ExprKind, E, Context.getSizeType(), OpLoc, 3355 E->getSourceRange().getEnd())); 3356} 3357 3358/// ActOnUnaryExprOrTypeTraitExpr - Handle @c sizeof(type) and @c sizeof @c 3359/// expr and the same for @c alignof and @c __alignof 3360/// Note that the ArgRange is invalid if isType is false. 3361ExprResult 3362Sema::ActOnUnaryExprOrTypeTraitExpr(SourceLocation OpLoc, 3363 UnaryExprOrTypeTrait ExprKind, bool IsType, 3364 void *TyOrEx, const SourceRange &ArgRange) { 3365 // If error parsing type, ignore. 3366 if (TyOrEx == 0) return ExprError(); 3367 3368 if (IsType) { 3369 TypeSourceInfo *TInfo; 3370 (void) GetTypeFromParser(ParsedType::getFromOpaquePtr(TyOrEx), &TInfo); 3371 return CreateUnaryExprOrTypeTraitExpr(TInfo, OpLoc, ExprKind, ArgRange); 3372 } 3373 3374 Expr *ArgEx = (Expr *)TyOrEx; 3375 ExprResult Result = CreateUnaryExprOrTypeTraitExpr(ArgEx, OpLoc, ExprKind); 3376 return Result; 3377} 3378 3379static QualType CheckRealImagOperand(Sema &S, ExprResult &V, SourceLocation Loc, 3380 bool IsReal) { 3381 if (V.get()->isTypeDependent()) 3382 return S.Context.DependentTy; 3383 3384 // _Real and _Imag are only l-values for normal l-values. 3385 if (V.get()->getObjectKind() != OK_Ordinary) { 3386 V = S.DefaultLvalueConversion(V.take()); 3387 if (V.isInvalid()) 3388 return QualType(); 3389 } 3390 3391 // These operators return the element type of a complex type. 3392 if (const ComplexType *CT = V.get()->getType()->getAs<ComplexType>()) 3393 return CT->getElementType(); 3394 3395 // Otherwise they pass through real integer and floating point types here. 3396 if (V.get()->getType()->isArithmeticType()) 3397 return V.get()->getType(); 3398 3399 // Test for placeholders. 3400 ExprResult PR = S.CheckPlaceholderExpr(V.get()); 3401 if (PR.isInvalid()) return QualType(); 3402 if (PR.get() != V.get()) { 3403 V = PR; 3404 return CheckRealImagOperand(S, V, Loc, IsReal); 3405 } 3406 3407 // Reject anything else. 3408 S.Diag(Loc, diag::err_realimag_invalid_type) << V.get()->getType() 3409 << (IsReal ? "__real" : "__imag"); 3410 return QualType(); 3411} 3412 3413 3414 3415ExprResult 3416Sema::ActOnPostfixUnaryOp(Scope *S, SourceLocation OpLoc, 3417 tok::TokenKind Kind, Expr *Input) { 3418 UnaryOperatorKind Opc; 3419 switch (Kind) { 3420 default: llvm_unreachable("Unknown unary op!"); 3421 case tok::plusplus: Opc = UO_PostInc; break; 3422 case tok::minusminus: Opc = UO_PostDec; break; 3423 } 3424 3425 // Since this might is a postfix expression, get rid of ParenListExprs. 3426 ExprResult Result = MaybeConvertParenListExprToParenExpr(S, Input); 3427 if (Result.isInvalid()) return ExprError(); 3428 Input = Result.take(); 3429 3430 return BuildUnaryOp(S, OpLoc, Opc, Input); 3431} 3432 3433/// \brief Diagnose if arithmetic on the given ObjC pointer is illegal. 3434/// 3435/// \return true on error 3436static bool checkArithmeticOnObjCPointer(Sema &S, 3437 SourceLocation opLoc, 3438 Expr *op) { 3439 assert(op->getType()->isObjCObjectPointerType()); 3440 if (S.LangOpts.ObjCRuntime.allowsPointerArithmetic()) 3441 return false; 3442 3443 S.Diag(opLoc, diag::err_arithmetic_nonfragile_interface) 3444 << op->getType()->castAs<ObjCObjectPointerType>()->getPointeeType() 3445 << op->getSourceRange(); 3446 return true; 3447} 3448 3449ExprResult 3450Sema::ActOnArraySubscriptExpr(Scope *S, Expr *base, SourceLocation lbLoc, 3451 Expr *idx, SourceLocation rbLoc) { 3452 // Since this might be a postfix expression, get rid of ParenListExprs. 3453 if (isa<ParenListExpr>(base)) { 3454 ExprResult result = MaybeConvertParenListExprToParenExpr(S, base); 3455 if (result.isInvalid()) return ExprError(); 3456 base = result.take(); 3457 } 3458 3459 // Handle any non-overload placeholder types in the base and index 3460 // expressions. We can't handle overloads here because the other 3461 // operand might be an overloadable type, in which case the overload 3462 // resolution for the operator overload should get the first crack 3463 // at the overload. 3464 if (base->getType()->isNonOverloadPlaceholderType()) { 3465 ExprResult result = CheckPlaceholderExpr(base); 3466 if (result.isInvalid()) return ExprError(); 3467 base = result.take(); 3468 } 3469 if (idx->getType()->isNonOverloadPlaceholderType()) { 3470 ExprResult result = CheckPlaceholderExpr(idx); 3471 if (result.isInvalid()) return ExprError(); 3472 idx = result.take(); 3473 } 3474 3475 // Build an unanalyzed expression if either operand is type-dependent. 3476 if (getLangOpts().CPlusPlus && 3477 (base->isTypeDependent() || idx->isTypeDependent())) { 3478 return Owned(new (Context) ArraySubscriptExpr(base, idx, 3479 Context.DependentTy, 3480 VK_LValue, OK_Ordinary, 3481 rbLoc)); 3482 } 3483 3484 // Use C++ overloaded-operator rules if either operand has record 3485 // type. The spec says to do this if either type is *overloadable*, 3486 // but enum types can't declare subscript operators or conversion 3487 // operators, so there's nothing interesting for overload resolution 3488 // to do if there aren't any record types involved. 3489 // 3490 // ObjC pointers have their own subscripting logic that is not tied 3491 // to overload resolution and so should not take this path. 3492 if (getLangOpts().CPlusPlus && 3493 (base->getType()->isRecordType() || 3494 (!base->getType()->isObjCObjectPointerType() && 3495 idx->getType()->isRecordType()))) { 3496 return CreateOverloadedArraySubscriptExpr(lbLoc, rbLoc, base, idx); 3497 } 3498 3499 return CreateBuiltinArraySubscriptExpr(base, lbLoc, idx, rbLoc); 3500} 3501 3502ExprResult 3503Sema::CreateBuiltinArraySubscriptExpr(Expr *Base, SourceLocation LLoc, 3504 Expr *Idx, SourceLocation RLoc) { 3505 Expr *LHSExp = Base; 3506 Expr *RHSExp = Idx; 3507 3508 // Perform default conversions. 3509 if (!LHSExp->getType()->getAs<VectorType>()) { 3510 ExprResult Result = DefaultFunctionArrayLvalueConversion(LHSExp); 3511 if (Result.isInvalid()) 3512 return ExprError(); 3513 LHSExp = Result.take(); 3514 } 3515 ExprResult Result = DefaultFunctionArrayLvalueConversion(RHSExp); 3516 if (Result.isInvalid()) 3517 return ExprError(); 3518 RHSExp = Result.take(); 3519 3520 QualType LHSTy = LHSExp->getType(), RHSTy = RHSExp->getType(); 3521 ExprValueKind VK = VK_LValue; 3522 ExprObjectKind OK = OK_Ordinary; 3523 3524 // C99 6.5.2.1p2: the expression e1[e2] is by definition precisely equivalent 3525 // to the expression *((e1)+(e2)). This means the array "Base" may actually be 3526 // in the subscript position. As a result, we need to derive the array base 3527 // and index from the expression types. 3528 Expr *BaseExpr, *IndexExpr; 3529 QualType ResultType; 3530 if (LHSTy->isDependentType() || RHSTy->isDependentType()) { 3531 BaseExpr = LHSExp; 3532 IndexExpr = RHSExp; 3533 ResultType = Context.DependentTy; 3534 } else if (const PointerType *PTy = LHSTy->getAs<PointerType>()) { 3535 BaseExpr = LHSExp; 3536 IndexExpr = RHSExp; 3537 ResultType = PTy->getPointeeType(); 3538 } else if (const ObjCObjectPointerType *PTy = 3539 LHSTy->getAs<ObjCObjectPointerType>()) { 3540 BaseExpr = LHSExp; 3541 IndexExpr = RHSExp; 3542 3543 // Use custom logic if this should be the pseudo-object subscript 3544 // expression. 3545 if (!LangOpts.ObjCRuntime.isSubscriptPointerArithmetic()) 3546 return BuildObjCSubscriptExpression(RLoc, BaseExpr, IndexExpr, 0, 0); 3547 3548 ResultType = PTy->getPointeeType(); 3549 if (!LangOpts.ObjCRuntime.allowsPointerArithmetic()) { 3550 Diag(LLoc, diag::err_subscript_nonfragile_interface) 3551 << ResultType << BaseExpr->getSourceRange(); 3552 return ExprError(); 3553 } 3554 } else if (const PointerType *PTy = RHSTy->getAs<PointerType>()) { 3555 // Handle the uncommon case of "123[Ptr]". 3556 BaseExpr = RHSExp; 3557 IndexExpr = LHSExp; 3558 ResultType = PTy->getPointeeType(); 3559 } else if (const ObjCObjectPointerType *PTy = 3560 RHSTy->getAs<ObjCObjectPointerType>()) { 3561 // Handle the uncommon case of "123[Ptr]". 3562 BaseExpr = RHSExp; 3563 IndexExpr = LHSExp; 3564 ResultType = PTy->getPointeeType(); 3565 if (!LangOpts.ObjCRuntime.allowsPointerArithmetic()) { 3566 Diag(LLoc, diag::err_subscript_nonfragile_interface) 3567 << ResultType << BaseExpr->getSourceRange(); 3568 return ExprError(); 3569 } 3570 } else if (const VectorType *VTy = LHSTy->getAs<VectorType>()) { 3571 BaseExpr = LHSExp; // vectors: V[123] 3572 IndexExpr = RHSExp; 3573 VK = LHSExp->getValueKind(); 3574 if (VK != VK_RValue) 3575 OK = OK_VectorComponent; 3576 3577 // FIXME: need to deal with const... 3578 ResultType = VTy->getElementType(); 3579 } else if (LHSTy->isArrayType()) { 3580 // If we see an array that wasn't promoted by 3581 // DefaultFunctionArrayLvalueConversion, it must be an array that 3582 // wasn't promoted because of the C90 rule that doesn't 3583 // allow promoting non-lvalue arrays. Warn, then 3584 // force the promotion here. 3585 Diag(LHSExp->getLocStart(), diag::ext_subscript_non_lvalue) << 3586 LHSExp->getSourceRange(); 3587 LHSExp = ImpCastExprToType(LHSExp, Context.getArrayDecayedType(LHSTy), 3588 CK_ArrayToPointerDecay).take(); 3589 LHSTy = LHSExp->getType(); 3590 3591 BaseExpr = LHSExp; 3592 IndexExpr = RHSExp; 3593 ResultType = LHSTy->getAs<PointerType>()->getPointeeType(); 3594 } else if (RHSTy->isArrayType()) { 3595 // Same as previous, except for 123[f().a] case 3596 Diag(RHSExp->getLocStart(), diag::ext_subscript_non_lvalue) << 3597 RHSExp->getSourceRange(); 3598 RHSExp = ImpCastExprToType(RHSExp, Context.getArrayDecayedType(RHSTy), 3599 CK_ArrayToPointerDecay).take(); 3600 RHSTy = RHSExp->getType(); 3601 3602 BaseExpr = RHSExp; 3603 IndexExpr = LHSExp; 3604 ResultType = RHSTy->getAs<PointerType>()->getPointeeType(); 3605 } else { 3606 return ExprError(Diag(LLoc, diag::err_typecheck_subscript_value) 3607 << LHSExp->getSourceRange() << RHSExp->getSourceRange()); 3608 } 3609 // C99 6.5.2.1p1 3610 if (!IndexExpr->getType()->isIntegerType() && !IndexExpr->isTypeDependent()) 3611 return ExprError(Diag(LLoc, diag::err_typecheck_subscript_not_integer) 3612 << IndexExpr->getSourceRange()); 3613 3614 if ((IndexExpr->getType()->isSpecificBuiltinType(BuiltinType::Char_S) || 3615 IndexExpr->getType()->isSpecificBuiltinType(BuiltinType::Char_U)) 3616 && !IndexExpr->isTypeDependent()) 3617 Diag(LLoc, diag::warn_subscript_is_char) << IndexExpr->getSourceRange(); 3618 3619 // C99 6.5.2.1p1: "shall have type "pointer to *object* type". Similarly, 3620 // C++ [expr.sub]p1: The type "T" shall be a completely-defined object 3621 // type. Note that Functions are not objects, and that (in C99 parlance) 3622 // incomplete types are not object types. 3623 if (ResultType->isFunctionType()) { 3624 Diag(BaseExpr->getLocStart(), diag::err_subscript_function_type) 3625 << ResultType << BaseExpr->getSourceRange(); 3626 return ExprError(); 3627 } 3628 3629 if (ResultType->isVoidType() && !getLangOpts().CPlusPlus) { 3630 // GNU extension: subscripting on pointer to void 3631 Diag(LLoc, diag::ext_gnu_subscript_void_type) 3632 << BaseExpr->getSourceRange(); 3633 3634 // C forbids expressions of unqualified void type from being l-values. 3635 // See IsCForbiddenLValueType. 3636 if (!ResultType.hasQualifiers()) VK = VK_RValue; 3637 } else if (!ResultType->isDependentType() && 3638 RequireCompleteType(LLoc, ResultType, 3639 diag::err_subscript_incomplete_type, BaseExpr)) 3640 return ExprError(); 3641 3642 assert(VK == VK_RValue || LangOpts.CPlusPlus || 3643 !ResultType.isCForbiddenLValueType()); 3644 3645 return Owned(new (Context) ArraySubscriptExpr(LHSExp, RHSExp, 3646 ResultType, VK, OK, RLoc)); 3647} 3648 3649ExprResult Sema::BuildCXXDefaultArgExpr(SourceLocation CallLoc, 3650 FunctionDecl *FD, 3651 ParmVarDecl *Param) { 3652 if (Param->hasUnparsedDefaultArg()) { 3653 Diag(CallLoc, 3654 diag::err_use_of_default_argument_to_function_declared_later) << 3655 FD << cast<CXXRecordDecl>(FD->getDeclContext())->getDeclName(); 3656 Diag(UnparsedDefaultArgLocs[Param], 3657 diag::note_default_argument_declared_here); 3658 return ExprError(); 3659 } 3660 3661 if (Param->hasUninstantiatedDefaultArg()) { 3662 Expr *UninstExpr = Param->getUninstantiatedDefaultArg(); 3663 3664 EnterExpressionEvaluationContext EvalContext(*this, PotentiallyEvaluated, 3665 Param); 3666 3667 // Instantiate the expression. 3668 MultiLevelTemplateArgumentList ArgList 3669 = getTemplateInstantiationArgs(FD, 0, /*RelativeToPrimary=*/true); 3670 3671 std::pair<const TemplateArgument *, unsigned> Innermost 3672 = ArgList.getInnermost(); 3673 InstantiatingTemplate Inst(*this, CallLoc, Param, 3674 ArrayRef<TemplateArgument>(Innermost.first, 3675 Innermost.second)); 3676 if (Inst) 3677 return ExprError(); 3678 3679 ExprResult Result; 3680 { 3681 // C++ [dcl.fct.default]p5: 3682 // The names in the [default argument] expression are bound, and 3683 // the semantic constraints are checked, at the point where the 3684 // default argument expression appears. 3685 ContextRAII SavedContext(*this, FD); 3686 LocalInstantiationScope Local(*this); 3687 Result = SubstExpr(UninstExpr, ArgList); 3688 } 3689 if (Result.isInvalid()) 3690 return ExprError(); 3691 3692 // Check the expression as an initializer for the parameter. 3693 InitializedEntity Entity 3694 = InitializedEntity::InitializeParameter(Context, Param); 3695 InitializationKind Kind 3696 = InitializationKind::CreateCopy(Param->getLocation(), 3697 /*FIXME:EqualLoc*/UninstExpr->getLocStart()); 3698 Expr *ResultE = Result.takeAs<Expr>(); 3699 3700 InitializationSequence InitSeq(*this, Entity, Kind, &ResultE, 1); 3701 Result = InitSeq.Perform(*this, Entity, Kind, ResultE); 3702 if (Result.isInvalid()) 3703 return ExprError(); 3704 3705 Expr *Arg = Result.takeAs<Expr>(); 3706 CheckCompletedExpr(Arg, Param->getOuterLocStart()); 3707 // Build the default argument expression. 3708 return Owned(CXXDefaultArgExpr::Create(Context, CallLoc, Param, Arg)); 3709 } 3710 3711 // If the default expression creates temporaries, we need to 3712 // push them to the current stack of expression temporaries so they'll 3713 // be properly destroyed. 3714 // FIXME: We should really be rebuilding the default argument with new 3715 // bound temporaries; see the comment in PR5810. 3716 // We don't need to do that with block decls, though, because 3717 // blocks in default argument expression can never capture anything. 3718 if (isa<ExprWithCleanups>(Param->getInit())) { 3719 // Set the "needs cleanups" bit regardless of whether there are 3720 // any explicit objects. 3721 ExprNeedsCleanups = true; 3722 3723 // Append all the objects to the cleanup list. Right now, this 3724 // should always be a no-op, because blocks in default argument 3725 // expressions should never be able to capture anything. 3726 assert(!cast<ExprWithCleanups>(Param->getInit())->getNumObjects() && 3727 "default argument expression has capturing blocks?"); 3728 } 3729 3730 // We already type-checked the argument, so we know it works. 3731 // Just mark all of the declarations in this potentially-evaluated expression 3732 // as being "referenced". 3733 MarkDeclarationsReferencedInExpr(Param->getDefaultArg(), 3734 /*SkipLocalVariables=*/true); 3735 return Owned(CXXDefaultArgExpr::Create(Context, CallLoc, Param)); 3736} 3737 3738 3739Sema::VariadicCallType 3740Sema::getVariadicCallType(FunctionDecl *FDecl, const FunctionProtoType *Proto, 3741 Expr *Fn) { 3742 if (Proto && Proto->isVariadic()) { 3743 if (dyn_cast_or_null<CXXConstructorDecl>(FDecl)) 3744 return VariadicConstructor; 3745 else if (Fn && Fn->getType()->isBlockPointerType()) 3746 return VariadicBlock; 3747 else if (FDecl) { 3748 if (CXXMethodDecl *Method = dyn_cast_or_null<CXXMethodDecl>(FDecl)) 3749 if (Method->isInstance()) 3750 return VariadicMethod; 3751 } 3752 return VariadicFunction; 3753 } 3754 return VariadicDoesNotApply; 3755} 3756 3757/// ConvertArgumentsForCall - Converts the arguments specified in 3758/// Args/NumArgs to the parameter types of the function FDecl with 3759/// function prototype Proto. Call is the call expression itself, and 3760/// Fn is the function expression. For a C++ member function, this 3761/// routine does not attempt to convert the object argument. Returns 3762/// true if the call is ill-formed. 3763bool 3764Sema::ConvertArgumentsForCall(CallExpr *Call, Expr *Fn, 3765 FunctionDecl *FDecl, 3766 const FunctionProtoType *Proto, 3767 Expr **Args, unsigned NumArgs, 3768 SourceLocation RParenLoc, 3769 bool IsExecConfig) { 3770 // Bail out early if calling a builtin with custom typechecking. 3771 // We don't need to do this in the 3772 if (FDecl) 3773 if (unsigned ID = FDecl->getBuiltinID()) 3774 if (Context.BuiltinInfo.hasCustomTypechecking(ID)) 3775 return false; 3776 3777 // C99 6.5.2.2p7 - the arguments are implicitly converted, as if by 3778 // assignment, to the types of the corresponding parameter, ... 3779 unsigned NumArgsInProto = Proto->getNumArgs(); 3780 bool Invalid = false; 3781 unsigned MinArgs = FDecl ? FDecl->getMinRequiredArguments() : NumArgsInProto; 3782 unsigned FnKind = Fn->getType()->isBlockPointerType() 3783 ? 1 /* block */ 3784 : (IsExecConfig ? 3 /* kernel function (exec config) */ 3785 : 0 /* function */); 3786 3787 // If too few arguments are available (and we don't have default 3788 // arguments for the remaining parameters), don't make the call. 3789 if (NumArgs < NumArgsInProto) { 3790 if (NumArgs < MinArgs) { 3791 if (MinArgs == 1 && FDecl && FDecl->getParamDecl(0)->getDeclName()) 3792 Diag(RParenLoc, MinArgs == NumArgsInProto && !Proto->isVariadic() 3793 ? diag::err_typecheck_call_too_few_args_one 3794 : diag::err_typecheck_call_too_few_args_at_least_one) 3795 << FnKind 3796 << FDecl->getParamDecl(0) << Fn->getSourceRange(); 3797 else 3798 Diag(RParenLoc, MinArgs == NumArgsInProto && !Proto->isVariadic() 3799 ? diag::err_typecheck_call_too_few_args 3800 : diag::err_typecheck_call_too_few_args_at_least) 3801 << FnKind 3802 << MinArgs << NumArgs << Fn->getSourceRange(); 3803 3804 // Emit the location of the prototype. 3805 if (FDecl && !FDecl->getBuiltinID() && !IsExecConfig) 3806 Diag(FDecl->getLocStart(), diag::note_callee_decl) 3807 << FDecl; 3808 3809 return true; 3810 } 3811 Call->setNumArgs(Context, NumArgsInProto); 3812 } 3813 3814 // If too many are passed and not variadic, error on the extras and drop 3815 // them. 3816 if (NumArgs > NumArgsInProto) { 3817 if (!Proto->isVariadic()) { 3818 if (NumArgsInProto == 1 && FDecl && FDecl->getParamDecl(0)->getDeclName()) 3819 Diag(Args[NumArgsInProto]->getLocStart(), 3820 MinArgs == NumArgsInProto 3821 ? diag::err_typecheck_call_too_many_args_one 3822 : diag::err_typecheck_call_too_many_args_at_most_one) 3823 << FnKind 3824 << FDecl->getParamDecl(0) << NumArgs << Fn->getSourceRange() 3825 << SourceRange(Args[NumArgsInProto]->getLocStart(), 3826 Args[NumArgs-1]->getLocEnd()); 3827 else 3828 Diag(Args[NumArgsInProto]->getLocStart(), 3829 MinArgs == NumArgsInProto 3830 ? diag::err_typecheck_call_too_many_args 3831 : diag::err_typecheck_call_too_many_args_at_most) 3832 << FnKind 3833 << NumArgsInProto << NumArgs << Fn->getSourceRange() 3834 << SourceRange(Args[NumArgsInProto]->getLocStart(), 3835 Args[NumArgs-1]->getLocEnd()); 3836 3837 // Emit the location of the prototype. 3838 if (FDecl && !FDecl->getBuiltinID() && !IsExecConfig) 3839 Diag(FDecl->getLocStart(), diag::note_callee_decl) 3840 << FDecl; 3841 3842 // This deletes the extra arguments. 3843 Call->setNumArgs(Context, NumArgsInProto); 3844 return true; 3845 } 3846 } 3847 SmallVector<Expr *, 8> AllArgs; 3848 VariadicCallType CallType = getVariadicCallType(FDecl, Proto, Fn); 3849 3850 Invalid = GatherArgumentsForCall(Call->getLocStart(), FDecl, 3851 Proto, 0, Args, NumArgs, AllArgs, CallType); 3852 if (Invalid) 3853 return true; 3854 unsigned TotalNumArgs = AllArgs.size(); 3855 for (unsigned i = 0; i < TotalNumArgs; ++i) 3856 Call->setArg(i, AllArgs[i]); 3857 3858 return false; 3859} 3860 3861bool Sema::GatherArgumentsForCall(SourceLocation CallLoc, 3862 FunctionDecl *FDecl, 3863 const FunctionProtoType *Proto, 3864 unsigned FirstProtoArg, 3865 Expr **Args, unsigned NumArgs, 3866 SmallVector<Expr *, 8> &AllArgs, 3867 VariadicCallType CallType, 3868 bool AllowExplicit, 3869 bool IsListInitialization) { 3870 unsigned NumArgsInProto = Proto->getNumArgs(); 3871 unsigned NumArgsToCheck = NumArgs; 3872 bool Invalid = false; 3873 if (NumArgs != NumArgsInProto) 3874 // Use default arguments for missing arguments 3875 NumArgsToCheck = NumArgsInProto; 3876 unsigned ArgIx = 0; 3877 // Continue to check argument types (even if we have too few/many args). 3878 for (unsigned i = FirstProtoArg; i != NumArgsToCheck; i++) { 3879 QualType ProtoArgType = Proto->getArgType(i); 3880 3881 Expr *Arg; 3882 ParmVarDecl *Param; 3883 if (ArgIx < NumArgs) { 3884 Arg = Args[ArgIx++]; 3885 3886 if (RequireCompleteType(Arg->getLocStart(), 3887 ProtoArgType, 3888 diag::err_call_incomplete_argument, Arg)) 3889 return true; 3890 3891 // Pass the argument 3892 Param = 0; 3893 if (FDecl && i < FDecl->getNumParams()) 3894 Param = FDecl->getParamDecl(i); 3895 3896 // Strip the unbridged-cast placeholder expression off, if applicable. 3897 if (Arg->getType() == Context.ARCUnbridgedCastTy && 3898 FDecl && FDecl->hasAttr<CFAuditedTransferAttr>() && 3899 (!Param || !Param->hasAttr<CFConsumedAttr>())) 3900 Arg = stripARCUnbridgedCast(Arg); 3901 3902 InitializedEntity Entity = Param ? 3903 InitializedEntity::InitializeParameter(Context, Param, ProtoArgType) 3904 : InitializedEntity::InitializeParameter(Context, ProtoArgType, 3905 Proto->isArgConsumed(i)); 3906 ExprResult ArgE = PerformCopyInitialization(Entity, 3907 SourceLocation(), 3908 Owned(Arg), 3909 IsListInitialization, 3910 AllowExplicit); 3911 if (ArgE.isInvalid()) 3912 return true; 3913 3914 Arg = ArgE.takeAs<Expr>(); 3915 } else { 3916 assert(FDecl && "can't use default arguments without a known callee"); 3917 Param = FDecl->getParamDecl(i); 3918 3919 ExprResult ArgExpr = 3920 BuildCXXDefaultArgExpr(CallLoc, FDecl, Param); 3921 if (ArgExpr.isInvalid()) 3922 return true; 3923 3924 Arg = ArgExpr.takeAs<Expr>(); 3925 } 3926 3927 // Check for array bounds violations for each argument to the call. This 3928 // check only triggers warnings when the argument isn't a more complex Expr 3929 // with its own checking, such as a BinaryOperator. 3930 CheckArrayAccess(Arg); 3931 3932 // Check for violations of C99 static array rules (C99 6.7.5.3p7). 3933 CheckStaticArrayArgument(CallLoc, Param, Arg); 3934 3935 AllArgs.push_back(Arg); 3936 } 3937 3938 // If this is a variadic call, handle args passed through "...". 3939 if (CallType != VariadicDoesNotApply) { 3940 // Assume that extern "C" functions with variadic arguments that 3941 // return __unknown_anytype aren't *really* variadic. 3942 if (Proto->getResultType() == Context.UnknownAnyTy && 3943 FDecl && FDecl->isExternC()) { 3944 for (unsigned i = ArgIx; i != NumArgs; ++i) { 3945 QualType paramType; // ignored 3946 ExprResult arg = checkUnknownAnyArg(CallLoc, Args[i], paramType); 3947 Invalid |= arg.isInvalid(); 3948 AllArgs.push_back(arg.take()); 3949 } 3950 3951 // Otherwise do argument promotion, (C99 6.5.2.2p7). 3952 } else { 3953 for (unsigned i = ArgIx; i != NumArgs; ++i) { 3954 ExprResult Arg = DefaultVariadicArgumentPromotion(Args[i], CallType, 3955 FDecl); 3956 Invalid |= Arg.isInvalid(); 3957 AllArgs.push_back(Arg.take()); 3958 } 3959 } 3960 3961 // Check for array bounds violations. 3962 for (unsigned i = ArgIx; i != NumArgs; ++i) 3963 CheckArrayAccess(Args[i]); 3964 } 3965 return Invalid; 3966} 3967 3968static void DiagnoseCalleeStaticArrayParam(Sema &S, ParmVarDecl *PVD) { 3969 TypeLoc TL = PVD->getTypeSourceInfo()->getTypeLoc(); 3970 if (ArrayTypeLoc ATL = TL.getAs<ArrayTypeLoc>()) 3971 S.Diag(PVD->getLocation(), diag::note_callee_static_array) 3972 << ATL.getLocalSourceRange(); 3973} 3974 3975/// CheckStaticArrayArgument - If the given argument corresponds to a static 3976/// array parameter, check that it is non-null, and that if it is formed by 3977/// array-to-pointer decay, the underlying array is sufficiently large. 3978/// 3979/// C99 6.7.5.3p7: If the keyword static also appears within the [ and ] of the 3980/// array type derivation, then for each call to the function, the value of the 3981/// corresponding actual argument shall provide access to the first element of 3982/// an array with at least as many elements as specified by the size expression. 3983void 3984Sema::CheckStaticArrayArgument(SourceLocation CallLoc, 3985 ParmVarDecl *Param, 3986 const Expr *ArgExpr) { 3987 // Static array parameters are not supported in C++. 3988 if (!Param || getLangOpts().CPlusPlus) 3989 return; 3990 3991 QualType OrigTy = Param->getOriginalType(); 3992 3993 const ArrayType *AT = Context.getAsArrayType(OrigTy); 3994 if (!AT || AT->getSizeModifier() != ArrayType::Static) 3995 return; 3996 3997 if (ArgExpr->isNullPointerConstant(Context, 3998 Expr::NPC_NeverValueDependent)) { 3999 Diag(CallLoc, diag::warn_null_arg) << ArgExpr->getSourceRange(); 4000 DiagnoseCalleeStaticArrayParam(*this, Param); 4001 return; 4002 } 4003 4004 const ConstantArrayType *CAT = dyn_cast<ConstantArrayType>(AT); 4005 if (!CAT) 4006 return; 4007 4008 const ConstantArrayType *ArgCAT = 4009 Context.getAsConstantArrayType(ArgExpr->IgnoreParenImpCasts()->getType()); 4010 if (!ArgCAT) 4011 return; 4012 4013 if (ArgCAT->getSize().ult(CAT->getSize())) { 4014 Diag(CallLoc, diag::warn_static_array_too_small) 4015 << ArgExpr->getSourceRange() 4016 << (unsigned) ArgCAT->getSize().getZExtValue() 4017 << (unsigned) CAT->getSize().getZExtValue(); 4018 DiagnoseCalleeStaticArrayParam(*this, Param); 4019 } 4020} 4021 4022/// Given a function expression of unknown-any type, try to rebuild it 4023/// to have a function type. 4024static ExprResult rebuildUnknownAnyFunction(Sema &S, Expr *fn); 4025 4026/// ActOnCallExpr - Handle a call to Fn with the specified array of arguments. 4027/// This provides the location of the left/right parens and a list of comma 4028/// locations. 4029ExprResult 4030Sema::ActOnCallExpr(Scope *S, Expr *Fn, SourceLocation LParenLoc, 4031 MultiExprArg ArgExprs, SourceLocation RParenLoc, 4032 Expr *ExecConfig, bool IsExecConfig) { 4033 // Since this might be a postfix expression, get rid of ParenListExprs. 4034 ExprResult Result = MaybeConvertParenListExprToParenExpr(S, Fn); 4035 if (Result.isInvalid()) return ExprError(); 4036 Fn = Result.take(); 4037 4038 if (getLangOpts().CPlusPlus) { 4039 // If this is a pseudo-destructor expression, build the call immediately. 4040 if (isa<CXXPseudoDestructorExpr>(Fn)) { 4041 if (!ArgExprs.empty()) { 4042 // Pseudo-destructor calls should not have any arguments. 4043 Diag(Fn->getLocStart(), diag::err_pseudo_dtor_call_with_args) 4044 << FixItHint::CreateRemoval( 4045 SourceRange(ArgExprs[0]->getLocStart(), 4046 ArgExprs.back()->getLocEnd())); 4047 } 4048 4049 return Owned(new (Context) CallExpr(Context, Fn, MultiExprArg(), 4050 Context.VoidTy, VK_RValue, 4051 RParenLoc)); 4052 } 4053 4054 // Determine whether this is a dependent call inside a C++ template, 4055 // in which case we won't do any semantic analysis now. 4056 // FIXME: Will need to cache the results of name lookup (including ADL) in 4057 // Fn. 4058 bool Dependent = false; 4059 if (Fn->isTypeDependent()) 4060 Dependent = true; 4061 else if (Expr::hasAnyTypeDependentArguments(ArgExprs)) 4062 Dependent = true; 4063 4064 if (Dependent) { 4065 if (ExecConfig) { 4066 return Owned(new (Context) CUDAKernelCallExpr( 4067 Context, Fn, cast<CallExpr>(ExecConfig), ArgExprs, 4068 Context.DependentTy, VK_RValue, RParenLoc)); 4069 } else { 4070 return Owned(new (Context) CallExpr(Context, Fn, ArgExprs, 4071 Context.DependentTy, VK_RValue, 4072 RParenLoc)); 4073 } 4074 } 4075 4076 // Determine whether this is a call to an object (C++ [over.call.object]). 4077 if (Fn->getType()->isRecordType()) 4078 return Owned(BuildCallToObjectOfClassType(S, Fn, LParenLoc, 4079 ArgExprs.data(), 4080 ArgExprs.size(), RParenLoc)); 4081 4082 if (Fn->getType() == Context.UnknownAnyTy) { 4083 ExprResult result = rebuildUnknownAnyFunction(*this, Fn); 4084 if (result.isInvalid()) return ExprError(); 4085 Fn = result.take(); 4086 } 4087 4088 if (Fn->getType() == Context.BoundMemberTy) { 4089 return BuildCallToMemberFunction(S, Fn, LParenLoc, ArgExprs.data(), 4090 ArgExprs.size(), RParenLoc); 4091 } 4092 } 4093 4094 // Check for overloaded calls. This can happen even in C due to extensions. 4095 if (Fn->getType() == Context.OverloadTy) { 4096 OverloadExpr::FindResult find = OverloadExpr::find(Fn); 4097 4098 // We aren't supposed to apply this logic for if there's an '&' involved. 4099 if (!find.HasFormOfMemberPointer) { 4100 OverloadExpr *ovl = find.Expression; 4101 if (isa<UnresolvedLookupExpr>(ovl)) { 4102 UnresolvedLookupExpr *ULE = cast<UnresolvedLookupExpr>(ovl); 4103 return BuildOverloadedCallExpr(S, Fn, ULE, LParenLoc, ArgExprs.data(), 4104 ArgExprs.size(), RParenLoc, ExecConfig); 4105 } else { 4106 return BuildCallToMemberFunction(S, Fn, LParenLoc, ArgExprs.data(), 4107 ArgExprs.size(), RParenLoc); 4108 } 4109 } 4110 } 4111 4112 // If we're directly calling a function, get the appropriate declaration. 4113 if (Fn->getType() == Context.UnknownAnyTy) { 4114 ExprResult result = rebuildUnknownAnyFunction(*this, Fn); 4115 if (result.isInvalid()) return ExprError(); 4116 Fn = result.take(); 4117 } 4118 4119 Expr *NakedFn = Fn->IgnoreParens(); 4120 4121 NamedDecl *NDecl = 0; 4122 if (UnaryOperator *UnOp = dyn_cast<UnaryOperator>(NakedFn)) 4123 if (UnOp->getOpcode() == UO_AddrOf) 4124 NakedFn = UnOp->getSubExpr()->IgnoreParens(); 4125 4126 if (isa<DeclRefExpr>(NakedFn)) 4127 NDecl = cast<DeclRefExpr>(NakedFn)->getDecl(); 4128 else if (isa<MemberExpr>(NakedFn)) 4129 NDecl = cast<MemberExpr>(NakedFn)->getMemberDecl(); 4130 4131 return BuildResolvedCallExpr(Fn, NDecl, LParenLoc, ArgExprs.data(), 4132 ArgExprs.size(), RParenLoc, ExecConfig, 4133 IsExecConfig); 4134} 4135 4136ExprResult 4137Sema::ActOnCUDAExecConfigExpr(Scope *S, SourceLocation LLLLoc, 4138 MultiExprArg ExecConfig, SourceLocation GGGLoc) { 4139 FunctionDecl *ConfigDecl = Context.getcudaConfigureCallDecl(); 4140 if (!ConfigDecl) 4141 return ExprError(Diag(LLLLoc, diag::err_undeclared_var_use) 4142 << "cudaConfigureCall"); 4143 QualType ConfigQTy = ConfigDecl->getType(); 4144 4145 DeclRefExpr *ConfigDR = new (Context) DeclRefExpr( 4146 ConfigDecl, false, ConfigQTy, VK_LValue, LLLLoc); 4147 MarkFunctionReferenced(LLLLoc, ConfigDecl); 4148 4149 return ActOnCallExpr(S, ConfigDR, LLLLoc, ExecConfig, GGGLoc, 0, 4150 /*IsExecConfig=*/true); 4151} 4152 4153/// ActOnAsTypeExpr - create a new asType (bitcast) from the arguments. 4154/// 4155/// __builtin_astype( value, dst type ) 4156/// 4157ExprResult Sema::ActOnAsTypeExpr(Expr *E, ParsedType ParsedDestTy, 4158 SourceLocation BuiltinLoc, 4159 SourceLocation RParenLoc) { 4160 ExprValueKind VK = VK_RValue; 4161 ExprObjectKind OK = OK_Ordinary; 4162 QualType DstTy = GetTypeFromParser(ParsedDestTy); 4163 QualType SrcTy = E->getType(); 4164 if (Context.getTypeSize(DstTy) != Context.getTypeSize(SrcTy)) 4165 return ExprError(Diag(BuiltinLoc, 4166 diag::err_invalid_astype_of_different_size) 4167 << DstTy 4168 << SrcTy 4169 << E->getSourceRange()); 4170 return Owned(new (Context) AsTypeExpr(E, DstTy, VK, OK, BuiltinLoc, 4171 RParenLoc)); 4172} 4173 4174/// BuildResolvedCallExpr - Build a call to a resolved expression, 4175/// i.e. an expression not of \p OverloadTy. The expression should 4176/// unary-convert to an expression of function-pointer or 4177/// block-pointer type. 4178/// 4179/// \param NDecl the declaration being called, if available 4180ExprResult 4181Sema::BuildResolvedCallExpr(Expr *Fn, NamedDecl *NDecl, 4182 SourceLocation LParenLoc, 4183 Expr **Args, unsigned NumArgs, 4184 SourceLocation RParenLoc, 4185 Expr *Config, bool IsExecConfig) { 4186 FunctionDecl *FDecl = dyn_cast_or_null<FunctionDecl>(NDecl); 4187 unsigned BuiltinID = (FDecl ? FDecl->getBuiltinID() : 0); 4188 4189 // Promote the function operand. 4190 // We special-case function promotion here because we only allow promoting 4191 // builtin functions to function pointers in the callee of a call. 4192 ExprResult Result; 4193 if (BuiltinID && 4194 Fn->getType()->isSpecificBuiltinType(BuiltinType::BuiltinFn)) { 4195 Result = ImpCastExprToType(Fn, Context.getPointerType(FDecl->getType()), 4196 CK_BuiltinFnToFnPtr).take(); 4197 } else { 4198 Result = UsualUnaryConversions(Fn); 4199 } 4200 if (Result.isInvalid()) 4201 return ExprError(); 4202 Fn = Result.take(); 4203 4204 // Make the call expr early, before semantic checks. This guarantees cleanup 4205 // of arguments and function on error. 4206 CallExpr *TheCall; 4207 if (Config) 4208 TheCall = new (Context) CUDAKernelCallExpr(Context, Fn, 4209 cast<CallExpr>(Config), 4210 llvm::makeArrayRef(Args,NumArgs), 4211 Context.BoolTy, 4212 VK_RValue, 4213 RParenLoc); 4214 else 4215 TheCall = new (Context) CallExpr(Context, Fn, 4216 llvm::makeArrayRef(Args, NumArgs), 4217 Context.BoolTy, 4218 VK_RValue, 4219 RParenLoc); 4220 4221 // Bail out early if calling a builtin with custom typechecking. 4222 if (BuiltinID && Context.BuiltinInfo.hasCustomTypechecking(BuiltinID)) 4223 return CheckBuiltinFunctionCall(BuiltinID, TheCall); 4224 4225 retry: 4226 const FunctionType *FuncT; 4227 if (const PointerType *PT = Fn->getType()->getAs<PointerType>()) { 4228 // C99 6.5.2.2p1 - "The expression that denotes the called function shall 4229 // have type pointer to function". 4230 FuncT = PT->getPointeeType()->getAs<FunctionType>(); 4231 if (FuncT == 0) 4232 return ExprError(Diag(LParenLoc, diag::err_typecheck_call_not_function) 4233 << Fn->getType() << Fn->getSourceRange()); 4234 } else if (const BlockPointerType *BPT = 4235 Fn->getType()->getAs<BlockPointerType>()) { 4236 FuncT = BPT->getPointeeType()->castAs<FunctionType>(); 4237 } else { 4238 // Handle calls to expressions of unknown-any type. 4239 if (Fn->getType() == Context.UnknownAnyTy) { 4240 ExprResult rewrite = rebuildUnknownAnyFunction(*this, Fn); 4241 if (rewrite.isInvalid()) return ExprError(); 4242 Fn = rewrite.take(); 4243 TheCall->setCallee(Fn); 4244 goto retry; 4245 } 4246 4247 return ExprError(Diag(LParenLoc, diag::err_typecheck_call_not_function) 4248 << Fn->getType() << Fn->getSourceRange()); 4249 } 4250 4251 if (getLangOpts().CUDA) { 4252 if (Config) { 4253 // CUDA: Kernel calls must be to global functions 4254 if (FDecl && !FDecl->hasAttr<CUDAGlobalAttr>()) 4255 return ExprError(Diag(LParenLoc,diag::err_kern_call_not_global_function) 4256 << FDecl->getName() << Fn->getSourceRange()); 4257 4258 // CUDA: Kernel function must have 'void' return type 4259 if (!FuncT->getResultType()->isVoidType()) 4260 return ExprError(Diag(LParenLoc, diag::err_kern_type_not_void_return) 4261 << Fn->getType() << Fn->getSourceRange()); 4262 } else { 4263 // CUDA: Calls to global functions must be configured 4264 if (FDecl && FDecl->hasAttr<CUDAGlobalAttr>()) 4265 return ExprError(Diag(LParenLoc, diag::err_global_call_not_config) 4266 << FDecl->getName() << Fn->getSourceRange()); 4267 } 4268 } 4269 4270 // Check for a valid return type 4271 if (CheckCallReturnType(FuncT->getResultType(), 4272 Fn->getLocStart(), TheCall, 4273 FDecl)) 4274 return ExprError(); 4275 4276 // We know the result type of the call, set it. 4277 TheCall->setType(FuncT->getCallResultType(Context)); 4278 TheCall->setValueKind(Expr::getValueKindForType(FuncT->getResultType())); 4279 4280 const FunctionProtoType *Proto = dyn_cast<FunctionProtoType>(FuncT); 4281 if (Proto) { 4282 if (ConvertArgumentsForCall(TheCall, Fn, FDecl, Proto, Args, NumArgs, 4283 RParenLoc, IsExecConfig)) 4284 return ExprError(); 4285 } else { 4286 assert(isa<FunctionNoProtoType>(FuncT) && "Unknown FunctionType!"); 4287 4288 if (FDecl) { 4289 // Check if we have too few/too many template arguments, based 4290 // on our knowledge of the function definition. 4291 const FunctionDecl *Def = 0; 4292 if (FDecl->hasBody(Def) && NumArgs != Def->param_size()) { 4293 Proto = Def->getType()->getAs<FunctionProtoType>(); 4294 if (!Proto || !(Proto->isVariadic() && NumArgs >= Def->param_size())) 4295 Diag(RParenLoc, diag::warn_call_wrong_number_of_arguments) 4296 << (NumArgs > Def->param_size()) << FDecl << Fn->getSourceRange(); 4297 } 4298 4299 // If the function we're calling isn't a function prototype, but we have 4300 // a function prototype from a prior declaratiom, use that prototype. 4301 if (!FDecl->hasPrototype()) 4302 Proto = FDecl->getType()->getAs<FunctionProtoType>(); 4303 } 4304 4305 // Promote the arguments (C99 6.5.2.2p6). 4306 for (unsigned i = 0; i != NumArgs; i++) { 4307 Expr *Arg = Args[i]; 4308 4309 if (Proto && i < Proto->getNumArgs()) { 4310 InitializedEntity Entity 4311 = InitializedEntity::InitializeParameter(Context, 4312 Proto->getArgType(i), 4313 Proto->isArgConsumed(i)); 4314 ExprResult ArgE = PerformCopyInitialization(Entity, 4315 SourceLocation(), 4316 Owned(Arg)); 4317 if (ArgE.isInvalid()) 4318 return true; 4319 4320 Arg = ArgE.takeAs<Expr>(); 4321 4322 } else { 4323 ExprResult ArgE = DefaultArgumentPromotion(Arg); 4324 4325 if (ArgE.isInvalid()) 4326 return true; 4327 4328 Arg = ArgE.takeAs<Expr>(); 4329 } 4330 4331 if (RequireCompleteType(Arg->getLocStart(), 4332 Arg->getType(), 4333 diag::err_call_incomplete_argument, Arg)) 4334 return ExprError(); 4335 4336 TheCall->setArg(i, Arg); 4337 } 4338 } 4339 4340 if (CXXMethodDecl *Method = dyn_cast_or_null<CXXMethodDecl>(FDecl)) 4341 if (!Method->isStatic()) 4342 return ExprError(Diag(LParenLoc, diag::err_member_call_without_object) 4343 << Fn->getSourceRange()); 4344 4345 // Check for sentinels 4346 if (NDecl) 4347 DiagnoseSentinelCalls(NDecl, LParenLoc, Args, NumArgs); 4348 4349 // Do special checking on direct calls to functions. 4350 if (FDecl) { 4351 if (CheckFunctionCall(FDecl, TheCall, Proto)) 4352 return ExprError(); 4353 4354 if (BuiltinID) 4355 return CheckBuiltinFunctionCall(BuiltinID, TheCall); 4356 } else if (NDecl) { 4357 if (CheckBlockCall(NDecl, TheCall, Proto)) 4358 return ExprError(); 4359 } 4360 4361 return MaybeBindToTemporary(TheCall); 4362} 4363 4364ExprResult 4365Sema::ActOnCompoundLiteral(SourceLocation LParenLoc, ParsedType Ty, 4366 SourceLocation RParenLoc, Expr *InitExpr) { 4367 assert((Ty != 0) && "ActOnCompoundLiteral(): missing type"); 4368 // FIXME: put back this assert when initializers are worked out. 4369 //assert((InitExpr != 0) && "ActOnCompoundLiteral(): missing expression"); 4370 4371 TypeSourceInfo *TInfo; 4372 QualType literalType = GetTypeFromParser(Ty, &TInfo); 4373 if (!TInfo) 4374 TInfo = Context.getTrivialTypeSourceInfo(literalType); 4375 4376 return BuildCompoundLiteralExpr(LParenLoc, TInfo, RParenLoc, InitExpr); 4377} 4378 4379ExprResult 4380Sema::BuildCompoundLiteralExpr(SourceLocation LParenLoc, TypeSourceInfo *TInfo, 4381 SourceLocation RParenLoc, Expr *LiteralExpr) { 4382 QualType literalType = TInfo->getType(); 4383 4384 if (literalType->isArrayType()) { 4385 if (RequireCompleteType(LParenLoc, Context.getBaseElementType(literalType), 4386 diag::err_illegal_decl_array_incomplete_type, 4387 SourceRange(LParenLoc, 4388 LiteralExpr->getSourceRange().getEnd()))) 4389 return ExprError(); 4390 if (literalType->isVariableArrayType()) 4391 return ExprError(Diag(LParenLoc, diag::err_variable_object_no_init) 4392 << SourceRange(LParenLoc, LiteralExpr->getSourceRange().getEnd())); 4393 } else if (!literalType->isDependentType() && 4394 RequireCompleteType(LParenLoc, literalType, 4395 diag::err_typecheck_decl_incomplete_type, 4396 SourceRange(LParenLoc, LiteralExpr->getSourceRange().getEnd()))) 4397 return ExprError(); 4398 4399 InitializedEntity Entity 4400 = InitializedEntity::InitializeTemporary(literalType); 4401 InitializationKind Kind 4402 = InitializationKind::CreateCStyleCast(LParenLoc, 4403 SourceRange(LParenLoc, RParenLoc), 4404 /*InitList=*/true); 4405 InitializationSequence InitSeq(*this, Entity, Kind, &LiteralExpr, 1); 4406 ExprResult Result = InitSeq.Perform(*this, Entity, Kind, LiteralExpr, 4407 &literalType); 4408 if (Result.isInvalid()) 4409 return ExprError(); 4410 LiteralExpr = Result.get(); 4411 4412 bool isFileScope = getCurFunctionOrMethodDecl() == 0; 4413 if (isFileScope) { // 6.5.2.5p3 4414 if (CheckForConstantInitializer(LiteralExpr, literalType)) 4415 return ExprError(); 4416 } 4417 4418 // In C, compound literals are l-values for some reason. 4419 ExprValueKind VK = getLangOpts().CPlusPlus ? VK_RValue : VK_LValue; 4420 4421 return MaybeBindToTemporary( 4422 new (Context) CompoundLiteralExpr(LParenLoc, TInfo, literalType, 4423 VK, LiteralExpr, isFileScope)); 4424} 4425 4426ExprResult 4427Sema::ActOnInitList(SourceLocation LBraceLoc, MultiExprArg InitArgList, 4428 SourceLocation RBraceLoc) { 4429 // Immediately handle non-overload placeholders. Overloads can be 4430 // resolved contextually, but everything else here can't. 4431 for (unsigned I = 0, E = InitArgList.size(); I != E; ++I) { 4432 if (InitArgList[I]->getType()->isNonOverloadPlaceholderType()) { 4433 ExprResult result = CheckPlaceholderExpr(InitArgList[I]); 4434 4435 // Ignore failures; dropping the entire initializer list because 4436 // of one failure would be terrible for indexing/etc. 4437 if (result.isInvalid()) continue; 4438 4439 InitArgList[I] = result.take(); 4440 } 4441 } 4442 4443 // Semantic analysis for initializers is done by ActOnDeclarator() and 4444 // CheckInitializer() - it requires knowledge of the object being intialized. 4445 4446 InitListExpr *E = new (Context) InitListExpr(Context, LBraceLoc, InitArgList, 4447 RBraceLoc); 4448 E->setType(Context.VoidTy); // FIXME: just a place holder for now. 4449 return Owned(E); 4450} 4451 4452/// Do an explicit extend of the given block pointer if we're in ARC. 4453static void maybeExtendBlockObject(Sema &S, ExprResult &E) { 4454 assert(E.get()->getType()->isBlockPointerType()); 4455 assert(E.get()->isRValue()); 4456 4457 // Only do this in an r-value context. 4458 if (!S.getLangOpts().ObjCAutoRefCount) return; 4459 4460 E = ImplicitCastExpr::Create(S.Context, E.get()->getType(), 4461 CK_ARCExtendBlockObject, E.get(), 4462 /*base path*/ 0, VK_RValue); 4463 S.ExprNeedsCleanups = true; 4464} 4465 4466/// Prepare a conversion of the given expression to an ObjC object 4467/// pointer type. 4468CastKind Sema::PrepareCastToObjCObjectPointer(ExprResult &E) { 4469 QualType type = E.get()->getType(); 4470 if (type->isObjCObjectPointerType()) { 4471 return CK_BitCast; 4472 } else if (type->isBlockPointerType()) { 4473 maybeExtendBlockObject(*this, E); 4474 return CK_BlockPointerToObjCPointerCast; 4475 } else { 4476 assert(type->isPointerType()); 4477 return CK_CPointerToObjCPointerCast; 4478 } 4479} 4480 4481/// Prepares for a scalar cast, performing all the necessary stages 4482/// except the final cast and returning the kind required. 4483CastKind Sema::PrepareScalarCast(ExprResult &Src, QualType DestTy) { 4484 // Both Src and Dest are scalar types, i.e. arithmetic or pointer. 4485 // Also, callers should have filtered out the invalid cases with 4486 // pointers. Everything else should be possible. 4487 4488 QualType SrcTy = Src.get()->getType(); 4489 if (Context.hasSameUnqualifiedType(SrcTy, DestTy)) 4490 return CK_NoOp; 4491 4492 switch (Type::ScalarTypeKind SrcKind = SrcTy->getScalarTypeKind()) { 4493 case Type::STK_MemberPointer: 4494 llvm_unreachable("member pointer type in C"); 4495 4496 case Type::STK_CPointer: 4497 case Type::STK_BlockPointer: 4498 case Type::STK_ObjCObjectPointer: 4499 switch (DestTy->getScalarTypeKind()) { 4500 case Type::STK_CPointer: 4501 return CK_BitCast; 4502 case Type::STK_BlockPointer: 4503 return (SrcKind == Type::STK_BlockPointer 4504 ? CK_BitCast : CK_AnyPointerToBlockPointerCast); 4505 case Type::STK_ObjCObjectPointer: 4506 if (SrcKind == Type::STK_ObjCObjectPointer) 4507 return CK_BitCast; 4508 if (SrcKind == Type::STK_CPointer) 4509 return CK_CPointerToObjCPointerCast; 4510 maybeExtendBlockObject(*this, Src); 4511 return CK_BlockPointerToObjCPointerCast; 4512 case Type::STK_Bool: 4513 return CK_PointerToBoolean; 4514 case Type::STK_Integral: 4515 return CK_PointerToIntegral; 4516 case Type::STK_Floating: 4517 case Type::STK_FloatingComplex: 4518 case Type::STK_IntegralComplex: 4519 case Type::STK_MemberPointer: 4520 llvm_unreachable("illegal cast from pointer"); 4521 } 4522 llvm_unreachable("Should have returned before this"); 4523 4524 case Type::STK_Bool: // casting from bool is like casting from an integer 4525 case Type::STK_Integral: 4526 switch (DestTy->getScalarTypeKind()) { 4527 case Type::STK_CPointer: 4528 case Type::STK_ObjCObjectPointer: 4529 case Type::STK_BlockPointer: 4530 if (Src.get()->isNullPointerConstant(Context, 4531 Expr::NPC_ValueDependentIsNull)) 4532 return CK_NullToPointer; 4533 return CK_IntegralToPointer; 4534 case Type::STK_Bool: 4535 return CK_IntegralToBoolean; 4536 case Type::STK_Integral: 4537 return CK_IntegralCast; 4538 case Type::STK_Floating: 4539 return CK_IntegralToFloating; 4540 case Type::STK_IntegralComplex: 4541 Src = ImpCastExprToType(Src.take(), 4542 DestTy->castAs<ComplexType>()->getElementType(), 4543 CK_IntegralCast); 4544 return CK_IntegralRealToComplex; 4545 case Type::STK_FloatingComplex: 4546 Src = ImpCastExprToType(Src.take(), 4547 DestTy->castAs<ComplexType>()->getElementType(), 4548 CK_IntegralToFloating); 4549 return CK_FloatingRealToComplex; 4550 case Type::STK_MemberPointer: 4551 llvm_unreachable("member pointer type in C"); 4552 } 4553 llvm_unreachable("Should have returned before this"); 4554 4555 case Type::STK_Floating: 4556 switch (DestTy->getScalarTypeKind()) { 4557 case Type::STK_Floating: 4558 return CK_FloatingCast; 4559 case Type::STK_Bool: 4560 return CK_FloatingToBoolean; 4561 case Type::STK_Integral: 4562 return CK_FloatingToIntegral; 4563 case Type::STK_FloatingComplex: 4564 Src = ImpCastExprToType(Src.take(), 4565 DestTy->castAs<ComplexType>()->getElementType(), 4566 CK_FloatingCast); 4567 return CK_FloatingRealToComplex; 4568 case Type::STK_IntegralComplex: 4569 Src = ImpCastExprToType(Src.take(), 4570 DestTy->castAs<ComplexType>()->getElementType(), 4571 CK_FloatingToIntegral); 4572 return CK_IntegralRealToComplex; 4573 case Type::STK_CPointer: 4574 case Type::STK_ObjCObjectPointer: 4575 case Type::STK_BlockPointer: 4576 llvm_unreachable("valid float->pointer cast?"); 4577 case Type::STK_MemberPointer: 4578 llvm_unreachable("member pointer type in C"); 4579 } 4580 llvm_unreachable("Should have returned before this"); 4581 4582 case Type::STK_FloatingComplex: 4583 switch (DestTy->getScalarTypeKind()) { 4584 case Type::STK_FloatingComplex: 4585 return CK_FloatingComplexCast; 4586 case Type::STK_IntegralComplex: 4587 return CK_FloatingComplexToIntegralComplex; 4588 case Type::STK_Floating: { 4589 QualType ET = SrcTy->castAs<ComplexType>()->getElementType(); 4590 if (Context.hasSameType(ET, DestTy)) 4591 return CK_FloatingComplexToReal; 4592 Src = ImpCastExprToType(Src.take(), ET, CK_FloatingComplexToReal); 4593 return CK_FloatingCast; 4594 } 4595 case Type::STK_Bool: 4596 return CK_FloatingComplexToBoolean; 4597 case Type::STK_Integral: 4598 Src = ImpCastExprToType(Src.take(), 4599 SrcTy->castAs<ComplexType>()->getElementType(), 4600 CK_FloatingComplexToReal); 4601 return CK_FloatingToIntegral; 4602 case Type::STK_CPointer: 4603 case Type::STK_ObjCObjectPointer: 4604 case Type::STK_BlockPointer: 4605 llvm_unreachable("valid complex float->pointer cast?"); 4606 case Type::STK_MemberPointer: 4607 llvm_unreachable("member pointer type in C"); 4608 } 4609 llvm_unreachable("Should have returned before this"); 4610 4611 case Type::STK_IntegralComplex: 4612 switch (DestTy->getScalarTypeKind()) { 4613 case Type::STK_FloatingComplex: 4614 return CK_IntegralComplexToFloatingComplex; 4615 case Type::STK_IntegralComplex: 4616 return CK_IntegralComplexCast; 4617 case Type::STK_Integral: { 4618 QualType ET = SrcTy->castAs<ComplexType>()->getElementType(); 4619 if (Context.hasSameType(ET, DestTy)) 4620 return CK_IntegralComplexToReal; 4621 Src = ImpCastExprToType(Src.take(), ET, CK_IntegralComplexToReal); 4622 return CK_IntegralCast; 4623 } 4624 case Type::STK_Bool: 4625 return CK_IntegralComplexToBoolean; 4626 case Type::STK_Floating: 4627 Src = ImpCastExprToType(Src.take(), 4628 SrcTy->castAs<ComplexType>()->getElementType(), 4629 CK_IntegralComplexToReal); 4630 return CK_IntegralToFloating; 4631 case Type::STK_CPointer: 4632 case Type::STK_ObjCObjectPointer: 4633 case Type::STK_BlockPointer: 4634 llvm_unreachable("valid complex int->pointer cast?"); 4635 case Type::STK_MemberPointer: 4636 llvm_unreachable("member pointer type in C"); 4637 } 4638 llvm_unreachable("Should have returned before this"); 4639 } 4640 4641 llvm_unreachable("Unhandled scalar cast"); 4642} 4643 4644bool Sema::CheckVectorCast(SourceRange R, QualType VectorTy, QualType Ty, 4645 CastKind &Kind) { 4646 assert(VectorTy->isVectorType() && "Not a vector type!"); 4647 4648 if (Ty->isVectorType() || Ty->isIntegerType()) { 4649 if (Context.getTypeSize(VectorTy) != Context.getTypeSize(Ty)) 4650 return Diag(R.getBegin(), 4651 Ty->isVectorType() ? 4652 diag::err_invalid_conversion_between_vectors : 4653 diag::err_invalid_conversion_between_vector_and_integer) 4654 << VectorTy << Ty << R; 4655 } else 4656 return Diag(R.getBegin(), 4657 diag::err_invalid_conversion_between_vector_and_scalar) 4658 << VectorTy << Ty << R; 4659 4660 Kind = CK_BitCast; 4661 return false; 4662} 4663 4664ExprResult Sema::CheckExtVectorCast(SourceRange R, QualType DestTy, 4665 Expr *CastExpr, CastKind &Kind) { 4666 assert(DestTy->isExtVectorType() && "Not an extended vector type!"); 4667 4668 QualType SrcTy = CastExpr->getType(); 4669 4670 // If SrcTy is a VectorType, the total size must match to explicitly cast to 4671 // an ExtVectorType. 4672 // In OpenCL, casts between vectors of different types are not allowed. 4673 // (See OpenCL 6.2). 4674 if (SrcTy->isVectorType()) { 4675 if (Context.getTypeSize(DestTy) != Context.getTypeSize(SrcTy) 4676 || (getLangOpts().OpenCL && 4677 (DestTy.getCanonicalType() != SrcTy.getCanonicalType()))) { 4678 Diag(R.getBegin(),diag::err_invalid_conversion_between_ext_vectors) 4679 << DestTy << SrcTy << R; 4680 return ExprError(); 4681 } 4682 Kind = CK_BitCast; 4683 return Owned(CastExpr); 4684 } 4685 4686 // All non-pointer scalars can be cast to ExtVector type. The appropriate 4687 // conversion will take place first from scalar to elt type, and then 4688 // splat from elt type to vector. 4689 if (SrcTy->isPointerType()) 4690 return Diag(R.getBegin(), 4691 diag::err_invalid_conversion_between_vector_and_scalar) 4692 << DestTy << SrcTy << R; 4693 4694 QualType DestElemTy = DestTy->getAs<ExtVectorType>()->getElementType(); 4695 ExprResult CastExprRes = Owned(CastExpr); 4696 CastKind CK = PrepareScalarCast(CastExprRes, DestElemTy); 4697 if (CastExprRes.isInvalid()) 4698 return ExprError(); 4699 CastExpr = ImpCastExprToType(CastExprRes.take(), DestElemTy, CK).take(); 4700 4701 Kind = CK_VectorSplat; 4702 return Owned(CastExpr); 4703} 4704 4705ExprResult 4706Sema::ActOnCastExpr(Scope *S, SourceLocation LParenLoc, 4707 Declarator &D, ParsedType &Ty, 4708 SourceLocation RParenLoc, Expr *CastExpr) { 4709 assert(!D.isInvalidType() && (CastExpr != 0) && 4710 "ActOnCastExpr(): missing type or expr"); 4711 4712 TypeSourceInfo *castTInfo = GetTypeForDeclaratorCast(D, CastExpr->getType()); 4713 if (D.isInvalidType()) 4714 return ExprError(); 4715 4716 if (getLangOpts().CPlusPlus) { 4717 // Check that there are no default arguments (C++ only). 4718 CheckExtraCXXDefaultArguments(D); 4719 } 4720 4721 checkUnusedDeclAttributes(D); 4722 4723 QualType castType = castTInfo->getType(); 4724 Ty = CreateParsedType(castType, castTInfo); 4725 4726 bool isVectorLiteral = false; 4727 4728 // Check for an altivec or OpenCL literal, 4729 // i.e. all the elements are integer constants. 4730 ParenExpr *PE = dyn_cast<ParenExpr>(CastExpr); 4731 ParenListExpr *PLE = dyn_cast<ParenListExpr>(CastExpr); 4732 if ((getLangOpts().AltiVec || getLangOpts().OpenCL) 4733 && castType->isVectorType() && (PE || PLE)) { 4734 if (PLE && PLE->getNumExprs() == 0) { 4735 Diag(PLE->getExprLoc(), diag::err_altivec_empty_initializer); 4736 return ExprError(); 4737 } 4738 if (PE || PLE->getNumExprs() == 1) { 4739 Expr *E = (PE ? PE->getSubExpr() : PLE->getExpr(0)); 4740 if (!E->getType()->isVectorType()) 4741 isVectorLiteral = true; 4742 } 4743 else 4744 isVectorLiteral = true; 4745 } 4746 4747 // If this is a vector initializer, '(' type ')' '(' init, ..., init ')' 4748 // then handle it as such. 4749 if (isVectorLiteral) 4750 return BuildVectorLiteral(LParenLoc, RParenLoc, CastExpr, castTInfo); 4751 4752 // If the Expr being casted is a ParenListExpr, handle it specially. 4753 // This is not an AltiVec-style cast, so turn the ParenListExpr into a 4754 // sequence of BinOp comma operators. 4755 if (isa<ParenListExpr>(CastExpr)) { 4756 ExprResult Result = MaybeConvertParenListExprToParenExpr(S, CastExpr); 4757 if (Result.isInvalid()) return ExprError(); 4758 CastExpr = Result.take(); 4759 } 4760 4761 return BuildCStyleCastExpr(LParenLoc, castTInfo, RParenLoc, CastExpr); 4762} 4763 4764ExprResult Sema::BuildVectorLiteral(SourceLocation LParenLoc, 4765 SourceLocation RParenLoc, Expr *E, 4766 TypeSourceInfo *TInfo) { 4767 assert((isa<ParenListExpr>(E) || isa<ParenExpr>(E)) && 4768 "Expected paren or paren list expression"); 4769 4770 Expr **exprs; 4771 unsigned numExprs; 4772 Expr *subExpr; 4773 SourceLocation LiteralLParenLoc, LiteralRParenLoc; 4774 if (ParenListExpr *PE = dyn_cast<ParenListExpr>(E)) { 4775 LiteralLParenLoc = PE->getLParenLoc(); 4776 LiteralRParenLoc = PE->getRParenLoc(); 4777 exprs = PE->getExprs(); 4778 numExprs = PE->getNumExprs(); 4779 } else { // isa<ParenExpr> by assertion at function entrance 4780 LiteralLParenLoc = cast<ParenExpr>(E)->getLParen(); 4781 LiteralRParenLoc = cast<ParenExpr>(E)->getRParen(); 4782 subExpr = cast<ParenExpr>(E)->getSubExpr(); 4783 exprs = &subExpr; 4784 numExprs = 1; 4785 } 4786 4787 QualType Ty = TInfo->getType(); 4788 assert(Ty->isVectorType() && "Expected vector type"); 4789 4790 SmallVector<Expr *, 8> initExprs; 4791 const VectorType *VTy = Ty->getAs<VectorType>(); 4792 unsigned numElems = Ty->getAs<VectorType>()->getNumElements(); 4793 4794 // '(...)' form of vector initialization in AltiVec: the number of 4795 // initializers must be one or must match the size of the vector. 4796 // If a single value is specified in the initializer then it will be 4797 // replicated to all the components of the vector 4798 if (VTy->getVectorKind() == VectorType::AltiVecVector) { 4799 // The number of initializers must be one or must match the size of the 4800 // vector. If a single value is specified in the initializer then it will 4801 // be replicated to all the components of the vector 4802 if (numExprs == 1) { 4803 QualType ElemTy = Ty->getAs<VectorType>()->getElementType(); 4804 ExprResult Literal = DefaultLvalueConversion(exprs[0]); 4805 if (Literal.isInvalid()) 4806 return ExprError(); 4807 Literal = ImpCastExprToType(Literal.take(), ElemTy, 4808 PrepareScalarCast(Literal, ElemTy)); 4809 return BuildCStyleCastExpr(LParenLoc, TInfo, RParenLoc, Literal.take()); 4810 } 4811 else if (numExprs < numElems) { 4812 Diag(E->getExprLoc(), 4813 diag::err_incorrect_number_of_vector_initializers); 4814 return ExprError(); 4815 } 4816 else 4817 initExprs.append(exprs, exprs + numExprs); 4818 } 4819 else { 4820 // For OpenCL, when the number of initializers is a single value, 4821 // it will be replicated to all components of the vector. 4822 if (getLangOpts().OpenCL && 4823 VTy->getVectorKind() == VectorType::GenericVector && 4824 numExprs == 1) { 4825 QualType ElemTy = Ty->getAs<VectorType>()->getElementType(); 4826 ExprResult Literal = DefaultLvalueConversion(exprs[0]); 4827 if (Literal.isInvalid()) 4828 return ExprError(); 4829 Literal = ImpCastExprToType(Literal.take(), ElemTy, 4830 PrepareScalarCast(Literal, ElemTy)); 4831 return BuildCStyleCastExpr(LParenLoc, TInfo, RParenLoc, Literal.take()); 4832 } 4833 4834 initExprs.append(exprs, exprs + numExprs); 4835 } 4836 // FIXME: This means that pretty-printing the final AST will produce curly 4837 // braces instead of the original commas. 4838 InitListExpr *initE = new (Context) InitListExpr(Context, LiteralLParenLoc, 4839 initExprs, LiteralRParenLoc); 4840 initE->setType(Ty); 4841 return BuildCompoundLiteralExpr(LParenLoc, TInfo, RParenLoc, initE); 4842} 4843 4844/// This is not an AltiVec-style cast or or C++ direct-initialization, so turn 4845/// the ParenListExpr into a sequence of comma binary operators. 4846ExprResult 4847Sema::MaybeConvertParenListExprToParenExpr(Scope *S, Expr *OrigExpr) { 4848 ParenListExpr *E = dyn_cast<ParenListExpr>(OrigExpr); 4849 if (!E) 4850 return Owned(OrigExpr); 4851 4852 ExprResult Result(E->getExpr(0)); 4853 4854 for (unsigned i = 1, e = E->getNumExprs(); i != e && !Result.isInvalid(); ++i) 4855 Result = ActOnBinOp(S, E->getExprLoc(), tok::comma, Result.get(), 4856 E->getExpr(i)); 4857 4858 if (Result.isInvalid()) return ExprError(); 4859 4860 return ActOnParenExpr(E->getLParenLoc(), E->getRParenLoc(), Result.get()); 4861} 4862 4863ExprResult Sema::ActOnParenListExpr(SourceLocation L, 4864 SourceLocation R, 4865 MultiExprArg Val) { 4866 Expr *expr = new (Context) ParenListExpr(Context, L, Val, R); 4867 return Owned(expr); 4868} 4869 4870/// \brief Emit a specialized diagnostic when one expression is a null pointer 4871/// constant and the other is not a pointer. Returns true if a diagnostic is 4872/// emitted. 4873bool Sema::DiagnoseConditionalForNull(Expr *LHSExpr, Expr *RHSExpr, 4874 SourceLocation QuestionLoc) { 4875 Expr *NullExpr = LHSExpr; 4876 Expr *NonPointerExpr = RHSExpr; 4877 Expr::NullPointerConstantKind NullKind = 4878 NullExpr->isNullPointerConstant(Context, 4879 Expr::NPC_ValueDependentIsNotNull); 4880 4881 if (NullKind == Expr::NPCK_NotNull) { 4882 NullExpr = RHSExpr; 4883 NonPointerExpr = LHSExpr; 4884 NullKind = 4885 NullExpr->isNullPointerConstant(Context, 4886 Expr::NPC_ValueDependentIsNotNull); 4887 } 4888 4889 if (NullKind == Expr::NPCK_NotNull) 4890 return false; 4891 4892 if (NullKind == Expr::NPCK_ZeroExpression) 4893 return false; 4894 4895 if (NullKind == Expr::NPCK_ZeroLiteral) { 4896 // In this case, check to make sure that we got here from a "NULL" 4897 // string in the source code. 4898 NullExpr = NullExpr->IgnoreParenImpCasts(); 4899 SourceLocation loc = NullExpr->getExprLoc(); 4900 if (!findMacroSpelling(loc, "NULL")) 4901 return false; 4902 } 4903 4904 int DiagType = (NullKind == Expr::NPCK_CXX11_nullptr); 4905 Diag(QuestionLoc, diag::err_typecheck_cond_incompatible_operands_null) 4906 << NonPointerExpr->getType() << DiagType 4907 << NonPointerExpr->getSourceRange(); 4908 return true; 4909} 4910 4911/// \brief Return false if the condition expression is valid, true otherwise. 4912static bool checkCondition(Sema &S, Expr *Cond) { 4913 QualType CondTy = Cond->getType(); 4914 4915 // C99 6.5.15p2 4916 if (CondTy->isScalarType()) return false; 4917 4918 // OpenCL: Sec 6.3.i says the condition is allowed to be a vector or scalar. 4919 if (S.getLangOpts().OpenCL && CondTy->isVectorType()) 4920 return false; 4921 4922 // Emit the proper error message. 4923 S.Diag(Cond->getLocStart(), S.getLangOpts().OpenCL ? 4924 diag::err_typecheck_cond_expect_scalar : 4925 diag::err_typecheck_cond_expect_scalar_or_vector) 4926 << CondTy; 4927 return true; 4928} 4929 4930/// \brief Return false if the two expressions can be converted to a vector, 4931/// true otherwise 4932static bool checkConditionalConvertScalarsToVectors(Sema &S, ExprResult &LHS, 4933 ExprResult &RHS, 4934 QualType CondTy) { 4935 // Both operands should be of scalar type. 4936 if (!LHS.get()->getType()->isScalarType()) { 4937 S.Diag(LHS.get()->getLocStart(), diag::err_typecheck_cond_expect_scalar) 4938 << CondTy; 4939 return true; 4940 } 4941 if (!RHS.get()->getType()->isScalarType()) { 4942 S.Diag(RHS.get()->getLocStart(), diag::err_typecheck_cond_expect_scalar) 4943 << CondTy; 4944 return true; 4945 } 4946 4947 // Implicity convert these scalars to the type of the condition. 4948 LHS = S.ImpCastExprToType(LHS.take(), CondTy, CK_IntegralCast); 4949 RHS = S.ImpCastExprToType(RHS.take(), CondTy, CK_IntegralCast); 4950 return false; 4951} 4952 4953/// \brief Handle when one or both operands are void type. 4954static QualType checkConditionalVoidType(Sema &S, ExprResult &LHS, 4955 ExprResult &RHS) { 4956 Expr *LHSExpr = LHS.get(); 4957 Expr *RHSExpr = RHS.get(); 4958 4959 if (!LHSExpr->getType()->isVoidType()) 4960 S.Diag(RHSExpr->getLocStart(), diag::ext_typecheck_cond_one_void) 4961 << RHSExpr->getSourceRange(); 4962 if (!RHSExpr->getType()->isVoidType()) 4963 S.Diag(LHSExpr->getLocStart(), diag::ext_typecheck_cond_one_void) 4964 << LHSExpr->getSourceRange(); 4965 LHS = S.ImpCastExprToType(LHS.take(), S.Context.VoidTy, CK_ToVoid); 4966 RHS = S.ImpCastExprToType(RHS.take(), S.Context.VoidTy, CK_ToVoid); 4967 return S.Context.VoidTy; 4968} 4969 4970/// \brief Return false if the NullExpr can be promoted to PointerTy, 4971/// true otherwise. 4972static bool checkConditionalNullPointer(Sema &S, ExprResult &NullExpr, 4973 QualType PointerTy) { 4974 if ((!PointerTy->isAnyPointerType() && !PointerTy->isBlockPointerType()) || 4975 !NullExpr.get()->isNullPointerConstant(S.Context, 4976 Expr::NPC_ValueDependentIsNull)) 4977 return true; 4978 4979 NullExpr = S.ImpCastExprToType(NullExpr.take(), PointerTy, CK_NullToPointer); 4980 return false; 4981} 4982 4983/// \brief Checks compatibility between two pointers and return the resulting 4984/// type. 4985static QualType checkConditionalPointerCompatibility(Sema &S, ExprResult &LHS, 4986 ExprResult &RHS, 4987 SourceLocation Loc) { 4988 QualType LHSTy = LHS.get()->getType(); 4989 QualType RHSTy = RHS.get()->getType(); 4990 4991 if (S.Context.hasSameType(LHSTy, RHSTy)) { 4992 // Two identical pointers types are always compatible. 4993 return LHSTy; 4994 } 4995 4996 QualType lhptee, rhptee; 4997 4998 // Get the pointee types. 4999 if (const BlockPointerType *LHSBTy = LHSTy->getAs<BlockPointerType>()) { 5000 lhptee = LHSBTy->getPointeeType(); 5001 rhptee = RHSTy->castAs<BlockPointerType>()->getPointeeType(); 5002 } else { 5003 lhptee = LHSTy->castAs<PointerType>()->getPointeeType(); 5004 rhptee = RHSTy->castAs<PointerType>()->getPointeeType(); 5005 } 5006 5007 // C99 6.5.15p6: If both operands are pointers to compatible types or to 5008 // differently qualified versions of compatible types, the result type is 5009 // a pointer to an appropriately qualified version of the composite 5010 // type. 5011 5012 // Only CVR-qualifiers exist in the standard, and the differently-qualified 5013 // clause doesn't make sense for our extensions. E.g. address space 2 should 5014 // be incompatible with address space 3: they may live on different devices or 5015 // anything. 5016 Qualifiers lhQual = lhptee.getQualifiers(); 5017 Qualifiers rhQual = rhptee.getQualifiers(); 5018 5019 unsigned MergedCVRQual = lhQual.getCVRQualifiers() | rhQual.getCVRQualifiers(); 5020 lhQual.removeCVRQualifiers(); 5021 rhQual.removeCVRQualifiers(); 5022 5023 lhptee = S.Context.getQualifiedType(lhptee.getUnqualifiedType(), lhQual); 5024 rhptee = S.Context.getQualifiedType(rhptee.getUnqualifiedType(), rhQual); 5025 5026 QualType CompositeTy = S.Context.mergeTypes(lhptee, rhptee); 5027 5028 if (CompositeTy.isNull()) { 5029 S.Diag(Loc, diag::warn_typecheck_cond_incompatible_pointers) 5030 << LHSTy << RHSTy << LHS.get()->getSourceRange() 5031 << RHS.get()->getSourceRange(); 5032 // In this situation, we assume void* type. No especially good 5033 // reason, but this is what gcc does, and we do have to pick 5034 // to get a consistent AST. 5035 QualType incompatTy = S.Context.getPointerType(S.Context.VoidTy); 5036 LHS = S.ImpCastExprToType(LHS.take(), incompatTy, CK_BitCast); 5037 RHS = S.ImpCastExprToType(RHS.take(), incompatTy, CK_BitCast); 5038 return incompatTy; 5039 } 5040 5041 // The pointer types are compatible. 5042 QualType ResultTy = CompositeTy.withCVRQualifiers(MergedCVRQual); 5043 ResultTy = S.Context.getPointerType(ResultTy); 5044 5045 LHS = S.ImpCastExprToType(LHS.take(), ResultTy, CK_BitCast); 5046 RHS = S.ImpCastExprToType(RHS.take(), ResultTy, CK_BitCast); 5047 return ResultTy; 5048} 5049 5050/// \brief Return the resulting type when the operands are both block pointers. 5051static QualType checkConditionalBlockPointerCompatibility(Sema &S, 5052 ExprResult &LHS, 5053 ExprResult &RHS, 5054 SourceLocation Loc) { 5055 QualType LHSTy = LHS.get()->getType(); 5056 QualType RHSTy = RHS.get()->getType(); 5057 5058 if (!LHSTy->isBlockPointerType() || !RHSTy->isBlockPointerType()) { 5059 if (LHSTy->isVoidPointerType() || RHSTy->isVoidPointerType()) { 5060 QualType destType = S.Context.getPointerType(S.Context.VoidTy); 5061 LHS = S.ImpCastExprToType(LHS.take(), destType, CK_BitCast); 5062 RHS = S.ImpCastExprToType(RHS.take(), destType, CK_BitCast); 5063 return destType; 5064 } 5065 S.Diag(Loc, diag::err_typecheck_cond_incompatible_operands) 5066 << LHSTy << RHSTy << LHS.get()->getSourceRange() 5067 << RHS.get()->getSourceRange(); 5068 return QualType(); 5069 } 5070 5071 // We have 2 block pointer types. 5072 return checkConditionalPointerCompatibility(S, LHS, RHS, Loc); 5073} 5074 5075/// \brief Return the resulting type when the operands are both pointers. 5076static QualType 5077checkConditionalObjectPointersCompatibility(Sema &S, ExprResult &LHS, 5078 ExprResult &RHS, 5079 SourceLocation Loc) { 5080 // get the pointer types 5081 QualType LHSTy = LHS.get()->getType(); 5082 QualType RHSTy = RHS.get()->getType(); 5083 5084 // get the "pointed to" types 5085 QualType lhptee = LHSTy->getAs<PointerType>()->getPointeeType(); 5086 QualType rhptee = RHSTy->getAs<PointerType>()->getPointeeType(); 5087 5088 // ignore qualifiers on void (C99 6.5.15p3, clause 6) 5089 if (lhptee->isVoidType() && rhptee->isIncompleteOrObjectType()) { 5090 // Figure out necessary qualifiers (C99 6.5.15p6) 5091 QualType destPointee 5092 = S.Context.getQualifiedType(lhptee, rhptee.getQualifiers()); 5093 QualType destType = S.Context.getPointerType(destPointee); 5094 // Add qualifiers if necessary. 5095 LHS = S.ImpCastExprToType(LHS.take(), destType, CK_NoOp); 5096 // Promote to void*. 5097 RHS = S.ImpCastExprToType(RHS.take(), destType, CK_BitCast); 5098 return destType; 5099 } 5100 if (rhptee->isVoidType() && lhptee->isIncompleteOrObjectType()) { 5101 QualType destPointee 5102 = S.Context.getQualifiedType(rhptee, lhptee.getQualifiers()); 5103 QualType destType = S.Context.getPointerType(destPointee); 5104 // Add qualifiers if necessary. 5105 RHS = S.ImpCastExprToType(RHS.take(), destType, CK_NoOp); 5106 // Promote to void*. 5107 LHS = S.ImpCastExprToType(LHS.take(), destType, CK_BitCast); 5108 return destType; 5109 } 5110 5111 return checkConditionalPointerCompatibility(S, LHS, RHS, Loc); 5112} 5113 5114/// \brief Return false if the first expression is not an integer and the second 5115/// expression is not a pointer, true otherwise. 5116static bool checkPointerIntegerMismatch(Sema &S, ExprResult &Int, 5117 Expr* PointerExpr, SourceLocation Loc, 5118 bool IsIntFirstExpr) { 5119 if (!PointerExpr->getType()->isPointerType() || 5120 !Int.get()->getType()->isIntegerType()) 5121 return false; 5122 5123 Expr *Expr1 = IsIntFirstExpr ? Int.get() : PointerExpr; 5124 Expr *Expr2 = IsIntFirstExpr ? PointerExpr : Int.get(); 5125 5126 S.Diag(Loc, diag::warn_typecheck_cond_pointer_integer_mismatch) 5127 << Expr1->getType() << Expr2->getType() 5128 << Expr1->getSourceRange() << Expr2->getSourceRange(); 5129 Int = S.ImpCastExprToType(Int.take(), PointerExpr->getType(), 5130 CK_IntegralToPointer); 5131 return true; 5132} 5133 5134/// Note that LHS is not null here, even if this is the gnu "x ?: y" extension. 5135/// In that case, LHS = cond. 5136/// C99 6.5.15 5137QualType Sema::CheckConditionalOperands(ExprResult &Cond, ExprResult &LHS, 5138 ExprResult &RHS, ExprValueKind &VK, 5139 ExprObjectKind &OK, 5140 SourceLocation QuestionLoc) { 5141 5142 ExprResult LHSResult = CheckPlaceholderExpr(LHS.get()); 5143 if (!LHSResult.isUsable()) return QualType(); 5144 LHS = LHSResult; 5145 5146 ExprResult RHSResult = CheckPlaceholderExpr(RHS.get()); 5147 if (!RHSResult.isUsable()) return QualType(); 5148 RHS = RHSResult; 5149 5150 // C++ is sufficiently different to merit its own checker. 5151 if (getLangOpts().CPlusPlus) 5152 return CXXCheckConditionalOperands(Cond, LHS, RHS, VK, OK, QuestionLoc); 5153 5154 VK = VK_RValue; 5155 OK = OK_Ordinary; 5156 5157 Cond = UsualUnaryConversions(Cond.take()); 5158 if (Cond.isInvalid()) 5159 return QualType(); 5160 LHS = UsualUnaryConversions(LHS.take()); 5161 if (LHS.isInvalid()) 5162 return QualType(); 5163 RHS = UsualUnaryConversions(RHS.take()); 5164 if (RHS.isInvalid()) 5165 return QualType(); 5166 5167 QualType CondTy = Cond.get()->getType(); 5168 QualType LHSTy = LHS.get()->getType(); 5169 QualType RHSTy = RHS.get()->getType(); 5170 5171 // first, check the condition. 5172 if (checkCondition(*this, Cond.get())) 5173 return QualType(); 5174 5175 // Now check the two expressions. 5176 if (LHSTy->isVectorType() || RHSTy->isVectorType()) 5177 return CheckVectorOperands(LHS, RHS, QuestionLoc, /*isCompAssign*/false); 5178 5179 // OpenCL: If the condition is a vector, and both operands are scalar, 5180 // attempt to implicity convert them to the vector type to act like the 5181 // built in select. 5182 if (getLangOpts().OpenCL && CondTy->isVectorType()) 5183 if (checkConditionalConvertScalarsToVectors(*this, LHS, RHS, CondTy)) 5184 return QualType(); 5185 5186 // If both operands have arithmetic type, do the usual arithmetic conversions 5187 // to find a common type: C99 6.5.15p3,5. 5188 if (LHSTy->isArithmeticType() && RHSTy->isArithmeticType()) { 5189 UsualArithmeticConversions(LHS, RHS); 5190 if (LHS.isInvalid() || RHS.isInvalid()) 5191 return QualType(); 5192 return LHS.get()->getType(); 5193 } 5194 5195 // If both operands are the same structure or union type, the result is that 5196 // type. 5197 if (const RecordType *LHSRT = LHSTy->getAs<RecordType>()) { // C99 6.5.15p3 5198 if (const RecordType *RHSRT = RHSTy->getAs<RecordType>()) 5199 if (LHSRT->getDecl() == RHSRT->getDecl()) 5200 // "If both the operands have structure or union type, the result has 5201 // that type." This implies that CV qualifiers are dropped. 5202 return LHSTy.getUnqualifiedType(); 5203 // FIXME: Type of conditional expression must be complete in C mode. 5204 } 5205 5206 // C99 6.5.15p5: "If both operands have void type, the result has void type." 5207 // The following || allows only one side to be void (a GCC-ism). 5208 if (LHSTy->isVoidType() || RHSTy->isVoidType()) { 5209 return checkConditionalVoidType(*this, LHS, RHS); 5210 } 5211 5212 // C99 6.5.15p6 - "if one operand is a null pointer constant, the result has 5213 // the type of the other operand." 5214 if (!checkConditionalNullPointer(*this, RHS, LHSTy)) return LHSTy; 5215 if (!checkConditionalNullPointer(*this, LHS, RHSTy)) return RHSTy; 5216 5217 // All objective-c pointer type analysis is done here. 5218 QualType compositeType = FindCompositeObjCPointerType(LHS, RHS, 5219 QuestionLoc); 5220 if (LHS.isInvalid() || RHS.isInvalid()) 5221 return QualType(); 5222 if (!compositeType.isNull()) 5223 return compositeType; 5224 5225 5226 // Handle block pointer types. 5227 if (LHSTy->isBlockPointerType() || RHSTy->isBlockPointerType()) 5228 return checkConditionalBlockPointerCompatibility(*this, LHS, RHS, 5229 QuestionLoc); 5230 5231 // Check constraints for C object pointers types (C99 6.5.15p3,6). 5232 if (LHSTy->isPointerType() && RHSTy->isPointerType()) 5233 return checkConditionalObjectPointersCompatibility(*this, LHS, RHS, 5234 QuestionLoc); 5235 5236 // GCC compatibility: soften pointer/integer mismatch. Note that 5237 // null pointers have been filtered out by this point. 5238 if (checkPointerIntegerMismatch(*this, LHS, RHS.get(), QuestionLoc, 5239 /*isIntFirstExpr=*/true)) 5240 return RHSTy; 5241 if (checkPointerIntegerMismatch(*this, RHS, LHS.get(), QuestionLoc, 5242 /*isIntFirstExpr=*/false)) 5243 return LHSTy; 5244 5245 // Emit a better diagnostic if one of the expressions is a null pointer 5246 // constant and the other is not a pointer type. In this case, the user most 5247 // likely forgot to take the address of the other expression. 5248 if (DiagnoseConditionalForNull(LHS.get(), RHS.get(), QuestionLoc)) 5249 return QualType(); 5250 5251 // Otherwise, the operands are not compatible. 5252 Diag(QuestionLoc, diag::err_typecheck_cond_incompatible_operands) 5253 << LHSTy << RHSTy << LHS.get()->getSourceRange() 5254 << RHS.get()->getSourceRange(); 5255 return QualType(); 5256} 5257 5258/// FindCompositeObjCPointerType - Helper method to find composite type of 5259/// two objective-c pointer types of the two input expressions. 5260QualType Sema::FindCompositeObjCPointerType(ExprResult &LHS, ExprResult &RHS, 5261 SourceLocation QuestionLoc) { 5262 QualType LHSTy = LHS.get()->getType(); 5263 QualType RHSTy = RHS.get()->getType(); 5264 5265 // Handle things like Class and struct objc_class*. Here we case the result 5266 // to the pseudo-builtin, because that will be implicitly cast back to the 5267 // redefinition type if an attempt is made to access its fields. 5268 if (LHSTy->isObjCClassType() && 5269 (Context.hasSameType(RHSTy, Context.getObjCClassRedefinitionType()))) { 5270 RHS = ImpCastExprToType(RHS.take(), LHSTy, CK_CPointerToObjCPointerCast); 5271 return LHSTy; 5272 } 5273 if (RHSTy->isObjCClassType() && 5274 (Context.hasSameType(LHSTy, Context.getObjCClassRedefinitionType()))) { 5275 LHS = ImpCastExprToType(LHS.take(), RHSTy, CK_CPointerToObjCPointerCast); 5276 return RHSTy; 5277 } 5278 // And the same for struct objc_object* / id 5279 if (LHSTy->isObjCIdType() && 5280 (Context.hasSameType(RHSTy, Context.getObjCIdRedefinitionType()))) { 5281 RHS = ImpCastExprToType(RHS.take(), LHSTy, CK_CPointerToObjCPointerCast); 5282 return LHSTy; 5283 } 5284 if (RHSTy->isObjCIdType() && 5285 (Context.hasSameType(LHSTy, Context.getObjCIdRedefinitionType()))) { 5286 LHS = ImpCastExprToType(LHS.take(), RHSTy, CK_CPointerToObjCPointerCast); 5287 return RHSTy; 5288 } 5289 // And the same for struct objc_selector* / SEL 5290 if (Context.isObjCSelType(LHSTy) && 5291 (Context.hasSameType(RHSTy, Context.getObjCSelRedefinitionType()))) { 5292 RHS = ImpCastExprToType(RHS.take(), LHSTy, CK_BitCast); 5293 return LHSTy; 5294 } 5295 if (Context.isObjCSelType(RHSTy) && 5296 (Context.hasSameType(LHSTy, Context.getObjCSelRedefinitionType()))) { 5297 LHS = ImpCastExprToType(LHS.take(), RHSTy, CK_BitCast); 5298 return RHSTy; 5299 } 5300 // Check constraints for Objective-C object pointers types. 5301 if (LHSTy->isObjCObjectPointerType() && RHSTy->isObjCObjectPointerType()) { 5302 5303 if (Context.getCanonicalType(LHSTy) == Context.getCanonicalType(RHSTy)) { 5304 // Two identical object pointer types are always compatible. 5305 return LHSTy; 5306 } 5307 const ObjCObjectPointerType *LHSOPT = LHSTy->castAs<ObjCObjectPointerType>(); 5308 const ObjCObjectPointerType *RHSOPT = RHSTy->castAs<ObjCObjectPointerType>(); 5309 QualType compositeType = LHSTy; 5310 5311 // If both operands are interfaces and either operand can be 5312 // assigned to the other, use that type as the composite 5313 // type. This allows 5314 // xxx ? (A*) a : (B*) b 5315 // where B is a subclass of A. 5316 // 5317 // Additionally, as for assignment, if either type is 'id' 5318 // allow silent coercion. Finally, if the types are 5319 // incompatible then make sure to use 'id' as the composite 5320 // type so the result is acceptable for sending messages to. 5321 5322 // FIXME: Consider unifying with 'areComparableObjCPointerTypes'. 5323 // It could return the composite type. 5324 if (Context.canAssignObjCInterfaces(LHSOPT, RHSOPT)) { 5325 compositeType = RHSOPT->isObjCBuiltinType() ? RHSTy : LHSTy; 5326 } else if (Context.canAssignObjCInterfaces(RHSOPT, LHSOPT)) { 5327 compositeType = LHSOPT->isObjCBuiltinType() ? LHSTy : RHSTy; 5328 } else if ((LHSTy->isObjCQualifiedIdType() || 5329 RHSTy->isObjCQualifiedIdType()) && 5330 Context.ObjCQualifiedIdTypesAreCompatible(LHSTy, RHSTy, true)) { 5331 // Need to handle "id<xx>" explicitly. 5332 // GCC allows qualified id and any Objective-C type to devolve to 5333 // id. Currently localizing to here until clear this should be 5334 // part of ObjCQualifiedIdTypesAreCompatible. 5335 compositeType = Context.getObjCIdType(); 5336 } else if (LHSTy->isObjCIdType() || RHSTy->isObjCIdType()) { 5337 compositeType = Context.getObjCIdType(); 5338 } else if (!(compositeType = 5339 Context.areCommonBaseCompatible(LHSOPT, RHSOPT)).isNull()) 5340 ; 5341 else { 5342 Diag(QuestionLoc, diag::ext_typecheck_cond_incompatible_operands) 5343 << LHSTy << RHSTy 5344 << LHS.get()->getSourceRange() << RHS.get()->getSourceRange(); 5345 QualType incompatTy = Context.getObjCIdType(); 5346 LHS = ImpCastExprToType(LHS.take(), incompatTy, CK_BitCast); 5347 RHS = ImpCastExprToType(RHS.take(), incompatTy, CK_BitCast); 5348 return incompatTy; 5349 } 5350 // The object pointer types are compatible. 5351 LHS = ImpCastExprToType(LHS.take(), compositeType, CK_BitCast); 5352 RHS = ImpCastExprToType(RHS.take(), compositeType, CK_BitCast); 5353 return compositeType; 5354 } 5355 // Check Objective-C object pointer types and 'void *' 5356 if (LHSTy->isVoidPointerType() && RHSTy->isObjCObjectPointerType()) { 5357 if (getLangOpts().ObjCAutoRefCount) { 5358 // ARC forbids the implicit conversion of object pointers to 'void *', 5359 // so these types are not compatible. 5360 Diag(QuestionLoc, diag::err_cond_voidptr_arc) << LHSTy << RHSTy 5361 << LHS.get()->getSourceRange() << RHS.get()->getSourceRange(); 5362 LHS = RHS = true; 5363 return QualType(); 5364 } 5365 QualType lhptee = LHSTy->getAs<PointerType>()->getPointeeType(); 5366 QualType rhptee = RHSTy->getAs<ObjCObjectPointerType>()->getPointeeType(); 5367 QualType destPointee 5368 = Context.getQualifiedType(lhptee, rhptee.getQualifiers()); 5369 QualType destType = Context.getPointerType(destPointee); 5370 // Add qualifiers if necessary. 5371 LHS = ImpCastExprToType(LHS.take(), destType, CK_NoOp); 5372 // Promote to void*. 5373 RHS = ImpCastExprToType(RHS.take(), destType, CK_BitCast); 5374 return destType; 5375 } 5376 if (LHSTy->isObjCObjectPointerType() && RHSTy->isVoidPointerType()) { 5377 if (getLangOpts().ObjCAutoRefCount) { 5378 // ARC forbids the implicit conversion of object pointers to 'void *', 5379 // so these types are not compatible. 5380 Diag(QuestionLoc, diag::err_cond_voidptr_arc) << LHSTy << RHSTy 5381 << LHS.get()->getSourceRange() << RHS.get()->getSourceRange(); 5382 LHS = RHS = true; 5383 return QualType(); 5384 } 5385 QualType lhptee = LHSTy->getAs<ObjCObjectPointerType>()->getPointeeType(); 5386 QualType rhptee = RHSTy->getAs<PointerType>()->getPointeeType(); 5387 QualType destPointee 5388 = Context.getQualifiedType(rhptee, lhptee.getQualifiers()); 5389 QualType destType = Context.getPointerType(destPointee); 5390 // Add qualifiers if necessary. 5391 RHS = ImpCastExprToType(RHS.take(), destType, CK_NoOp); 5392 // Promote to void*. 5393 LHS = ImpCastExprToType(LHS.take(), destType, CK_BitCast); 5394 return destType; 5395 } 5396 return QualType(); 5397} 5398 5399/// SuggestParentheses - Emit a note with a fixit hint that wraps 5400/// ParenRange in parentheses. 5401static void SuggestParentheses(Sema &Self, SourceLocation Loc, 5402 const PartialDiagnostic &Note, 5403 SourceRange ParenRange) { 5404 SourceLocation EndLoc = Self.PP.getLocForEndOfToken(ParenRange.getEnd()); 5405 if (ParenRange.getBegin().isFileID() && ParenRange.getEnd().isFileID() && 5406 EndLoc.isValid()) { 5407 Self.Diag(Loc, Note) 5408 << FixItHint::CreateInsertion(ParenRange.getBegin(), "(") 5409 << FixItHint::CreateInsertion(EndLoc, ")"); 5410 } else { 5411 // We can't display the parentheses, so just show the bare note. 5412 Self.Diag(Loc, Note) << ParenRange; 5413 } 5414} 5415 5416static bool IsArithmeticOp(BinaryOperatorKind Opc) { 5417 return Opc >= BO_Mul && Opc <= BO_Shr; 5418} 5419 5420/// IsArithmeticBinaryExpr - Returns true if E is an arithmetic binary 5421/// expression, either using a built-in or overloaded operator, 5422/// and sets *OpCode to the opcode and *RHSExprs to the right-hand side 5423/// expression. 5424static bool IsArithmeticBinaryExpr(Expr *E, BinaryOperatorKind *Opcode, 5425 Expr **RHSExprs) { 5426 // Don't strip parenthesis: we should not warn if E is in parenthesis. 5427 E = E->IgnoreImpCasts(); 5428 E = E->IgnoreConversionOperator(); 5429 E = E->IgnoreImpCasts(); 5430 5431 // Built-in binary operator. 5432 if (BinaryOperator *OP = dyn_cast<BinaryOperator>(E)) { 5433 if (IsArithmeticOp(OP->getOpcode())) { 5434 *Opcode = OP->getOpcode(); 5435 *RHSExprs = OP->getRHS(); 5436 return true; 5437 } 5438 } 5439 5440 // Overloaded operator. 5441 if (CXXOperatorCallExpr *Call = dyn_cast<CXXOperatorCallExpr>(E)) { 5442 if (Call->getNumArgs() != 2) 5443 return false; 5444 5445 // Make sure this is really a binary operator that is safe to pass into 5446 // BinaryOperator::getOverloadedOpcode(), e.g. it's not a subscript op. 5447 OverloadedOperatorKind OO = Call->getOperator(); 5448 if (OO < OO_Plus || OO > OO_Arrow || 5449 OO == OO_PlusPlus || OO == OO_MinusMinus) 5450 return false; 5451 5452 BinaryOperatorKind OpKind = BinaryOperator::getOverloadedOpcode(OO); 5453 if (IsArithmeticOp(OpKind)) { 5454 *Opcode = OpKind; 5455 *RHSExprs = Call->getArg(1); 5456 return true; 5457 } 5458 } 5459 5460 return false; 5461} 5462 5463static bool IsLogicOp(BinaryOperatorKind Opc) { 5464 return (Opc >= BO_LT && Opc <= BO_NE) || (Opc >= BO_LAnd && Opc <= BO_LOr); 5465} 5466 5467/// ExprLooksBoolean - Returns true if E looks boolean, i.e. it has boolean type 5468/// or is a logical expression such as (x==y) which has int type, but is 5469/// commonly interpreted as boolean. 5470static bool ExprLooksBoolean(Expr *E) { 5471 E = E->IgnoreParenImpCasts(); 5472 5473 if (E->getType()->isBooleanType()) 5474 return true; 5475 if (BinaryOperator *OP = dyn_cast<BinaryOperator>(E)) 5476 return IsLogicOp(OP->getOpcode()); 5477 if (UnaryOperator *OP = dyn_cast<UnaryOperator>(E)) 5478 return OP->getOpcode() == UO_LNot; 5479 5480 return false; 5481} 5482 5483/// DiagnoseConditionalPrecedence - Emit a warning when a conditional operator 5484/// and binary operator are mixed in a way that suggests the programmer assumed 5485/// the conditional operator has higher precedence, for example: 5486/// "int x = a + someBinaryCondition ? 1 : 2". 5487static void DiagnoseConditionalPrecedence(Sema &Self, 5488 SourceLocation OpLoc, 5489 Expr *Condition, 5490 Expr *LHSExpr, 5491 Expr *RHSExpr) { 5492 BinaryOperatorKind CondOpcode; 5493 Expr *CondRHS; 5494 5495 if (!IsArithmeticBinaryExpr(Condition, &CondOpcode, &CondRHS)) 5496 return; 5497 if (!ExprLooksBoolean(CondRHS)) 5498 return; 5499 5500 // The condition is an arithmetic binary expression, with a right- 5501 // hand side that looks boolean, so warn. 5502 5503 Self.Diag(OpLoc, diag::warn_precedence_conditional) 5504 << Condition->getSourceRange() 5505 << BinaryOperator::getOpcodeStr(CondOpcode); 5506 5507 SuggestParentheses(Self, OpLoc, 5508 Self.PDiag(diag::note_precedence_silence) 5509 << BinaryOperator::getOpcodeStr(CondOpcode), 5510 SourceRange(Condition->getLocStart(), Condition->getLocEnd())); 5511 5512 SuggestParentheses(Self, OpLoc, 5513 Self.PDiag(diag::note_precedence_conditional_first), 5514 SourceRange(CondRHS->getLocStart(), RHSExpr->getLocEnd())); 5515} 5516 5517/// ActOnConditionalOp - Parse a ?: operation. Note that 'LHS' may be null 5518/// in the case of a the GNU conditional expr extension. 5519ExprResult Sema::ActOnConditionalOp(SourceLocation QuestionLoc, 5520 SourceLocation ColonLoc, 5521 Expr *CondExpr, Expr *LHSExpr, 5522 Expr *RHSExpr) { 5523 // If this is the gnu "x ?: y" extension, analyze the types as though the LHS 5524 // was the condition. 5525 OpaqueValueExpr *opaqueValue = 0; 5526 Expr *commonExpr = 0; 5527 if (LHSExpr == 0) { 5528 commonExpr = CondExpr; 5529 5530 // We usually want to apply unary conversions *before* saving, except 5531 // in the special case of a C++ l-value conditional. 5532 if (!(getLangOpts().CPlusPlus 5533 && !commonExpr->isTypeDependent() 5534 && commonExpr->getValueKind() == RHSExpr->getValueKind() 5535 && commonExpr->isGLValue() 5536 && commonExpr->isOrdinaryOrBitFieldObject() 5537 && RHSExpr->isOrdinaryOrBitFieldObject() 5538 && Context.hasSameType(commonExpr->getType(), RHSExpr->getType()))) { 5539 ExprResult commonRes = UsualUnaryConversions(commonExpr); 5540 if (commonRes.isInvalid()) 5541 return ExprError(); 5542 commonExpr = commonRes.take(); 5543 } 5544 5545 opaqueValue = new (Context) OpaqueValueExpr(commonExpr->getExprLoc(), 5546 commonExpr->getType(), 5547 commonExpr->getValueKind(), 5548 commonExpr->getObjectKind(), 5549 commonExpr); 5550 LHSExpr = CondExpr = opaqueValue; 5551 } 5552 5553 ExprValueKind VK = VK_RValue; 5554 ExprObjectKind OK = OK_Ordinary; 5555 ExprResult Cond = Owned(CondExpr), LHS = Owned(LHSExpr), RHS = Owned(RHSExpr); 5556 QualType result = CheckConditionalOperands(Cond, LHS, RHS, 5557 VK, OK, QuestionLoc); 5558 if (result.isNull() || Cond.isInvalid() || LHS.isInvalid() || 5559 RHS.isInvalid()) 5560 return ExprError(); 5561 5562 DiagnoseConditionalPrecedence(*this, QuestionLoc, Cond.get(), LHS.get(), 5563 RHS.get()); 5564 5565 if (!commonExpr) 5566 return Owned(new (Context) ConditionalOperator(Cond.take(), QuestionLoc, 5567 LHS.take(), ColonLoc, 5568 RHS.take(), result, VK, OK)); 5569 5570 return Owned(new (Context) 5571 BinaryConditionalOperator(commonExpr, opaqueValue, Cond.take(), LHS.take(), 5572 RHS.take(), QuestionLoc, ColonLoc, result, VK, 5573 OK)); 5574} 5575 5576// checkPointerTypesForAssignment - This is a very tricky routine (despite 5577// being closely modeled after the C99 spec:-). The odd characteristic of this 5578// routine is it effectively iqnores the qualifiers on the top level pointee. 5579// This circumvents the usual type rules specified in 6.2.7p1 & 6.7.5.[1-3]. 5580// FIXME: add a couple examples in this comment. 5581static Sema::AssignConvertType 5582checkPointerTypesForAssignment(Sema &S, QualType LHSType, QualType RHSType) { 5583 assert(LHSType.isCanonical() && "LHS not canonicalized!"); 5584 assert(RHSType.isCanonical() && "RHS not canonicalized!"); 5585 5586 // get the "pointed to" type (ignoring qualifiers at the top level) 5587 const Type *lhptee, *rhptee; 5588 Qualifiers lhq, rhq; 5589 llvm::tie(lhptee, lhq) = cast<PointerType>(LHSType)->getPointeeType().split(); 5590 llvm::tie(rhptee, rhq) = cast<PointerType>(RHSType)->getPointeeType().split(); 5591 5592 Sema::AssignConvertType ConvTy = Sema::Compatible; 5593 5594 // C99 6.5.16.1p1: This following citation is common to constraints 5595 // 3 & 4 (below). ...and the type *pointed to* by the left has all the 5596 // qualifiers of the type *pointed to* by the right; 5597 Qualifiers lq; 5598 5599 // As a special case, 'non-__weak A *' -> 'non-__weak const *' is okay. 5600 if (lhq.getObjCLifetime() != rhq.getObjCLifetime() && 5601 lhq.compatiblyIncludesObjCLifetime(rhq)) { 5602 // Ignore lifetime for further calculation. 5603 lhq.removeObjCLifetime(); 5604 rhq.removeObjCLifetime(); 5605 } 5606 5607 if (!lhq.compatiblyIncludes(rhq)) { 5608 // Treat address-space mismatches as fatal. TODO: address subspaces 5609 if (lhq.getAddressSpace() != rhq.getAddressSpace()) 5610 ConvTy = Sema::IncompatiblePointerDiscardsQualifiers; 5611 5612 // It's okay to add or remove GC or lifetime qualifiers when converting to 5613 // and from void*. 5614 else if (lhq.withoutObjCGCAttr().withoutObjCLifetime() 5615 .compatiblyIncludes( 5616 rhq.withoutObjCGCAttr().withoutObjCLifetime()) 5617 && (lhptee->isVoidType() || rhptee->isVoidType())) 5618 ; // keep old 5619 5620 // Treat lifetime mismatches as fatal. 5621 else if (lhq.getObjCLifetime() != rhq.getObjCLifetime()) 5622 ConvTy = Sema::IncompatiblePointerDiscardsQualifiers; 5623 5624 // For GCC compatibility, other qualifier mismatches are treated 5625 // as still compatible in C. 5626 else ConvTy = Sema::CompatiblePointerDiscardsQualifiers; 5627 } 5628 5629 // C99 6.5.16.1p1 (constraint 4): If one operand is a pointer to an object or 5630 // incomplete type and the other is a pointer to a qualified or unqualified 5631 // version of void... 5632 if (lhptee->isVoidType()) { 5633 if (rhptee->isIncompleteOrObjectType()) 5634 return ConvTy; 5635 5636 // As an extension, we allow cast to/from void* to function pointer. 5637 assert(rhptee->isFunctionType()); 5638 return Sema::FunctionVoidPointer; 5639 } 5640 5641 if (rhptee->isVoidType()) { 5642 if (lhptee->isIncompleteOrObjectType()) 5643 return ConvTy; 5644 5645 // As an extension, we allow cast to/from void* to function pointer. 5646 assert(lhptee->isFunctionType()); 5647 return Sema::FunctionVoidPointer; 5648 } 5649 5650 // C99 6.5.16.1p1 (constraint 3): both operands are pointers to qualified or 5651 // unqualified versions of compatible types, ... 5652 QualType ltrans = QualType(lhptee, 0), rtrans = QualType(rhptee, 0); 5653 if (!S.Context.typesAreCompatible(ltrans, rtrans)) { 5654 // Check if the pointee types are compatible ignoring the sign. 5655 // We explicitly check for char so that we catch "char" vs 5656 // "unsigned char" on systems where "char" is unsigned. 5657 if (lhptee->isCharType()) 5658 ltrans = S.Context.UnsignedCharTy; 5659 else if (lhptee->hasSignedIntegerRepresentation()) 5660 ltrans = S.Context.getCorrespondingUnsignedType(ltrans); 5661 5662 if (rhptee->isCharType()) 5663 rtrans = S.Context.UnsignedCharTy; 5664 else if (rhptee->hasSignedIntegerRepresentation()) 5665 rtrans = S.Context.getCorrespondingUnsignedType(rtrans); 5666 5667 if (ltrans == rtrans) { 5668 // Types are compatible ignoring the sign. Qualifier incompatibility 5669 // takes priority over sign incompatibility because the sign 5670 // warning can be disabled. 5671 if (ConvTy != Sema::Compatible) 5672 return ConvTy; 5673 5674 return Sema::IncompatiblePointerSign; 5675 } 5676 5677 // If we are a multi-level pointer, it's possible that our issue is simply 5678 // one of qualification - e.g. char ** -> const char ** is not allowed. If 5679 // the eventual target type is the same and the pointers have the same 5680 // level of indirection, this must be the issue. 5681 if (isa<PointerType>(lhptee) && isa<PointerType>(rhptee)) { 5682 do { 5683 lhptee = cast<PointerType>(lhptee)->getPointeeType().getTypePtr(); 5684 rhptee = cast<PointerType>(rhptee)->getPointeeType().getTypePtr(); 5685 } while (isa<PointerType>(lhptee) && isa<PointerType>(rhptee)); 5686 5687 if (lhptee == rhptee) 5688 return Sema::IncompatibleNestedPointerQualifiers; 5689 } 5690 5691 // General pointer incompatibility takes priority over qualifiers. 5692 return Sema::IncompatiblePointer; 5693 } 5694 if (!S.getLangOpts().CPlusPlus && 5695 S.IsNoReturnConversion(ltrans, rtrans, ltrans)) 5696 return Sema::IncompatiblePointer; 5697 return ConvTy; 5698} 5699 5700/// checkBlockPointerTypesForAssignment - This routine determines whether two 5701/// block pointer types are compatible or whether a block and normal pointer 5702/// are compatible. It is more restrict than comparing two function pointer 5703// types. 5704static Sema::AssignConvertType 5705checkBlockPointerTypesForAssignment(Sema &S, QualType LHSType, 5706 QualType RHSType) { 5707 assert(LHSType.isCanonical() && "LHS not canonicalized!"); 5708 assert(RHSType.isCanonical() && "RHS not canonicalized!"); 5709 5710 QualType lhptee, rhptee; 5711 5712 // get the "pointed to" type (ignoring qualifiers at the top level) 5713 lhptee = cast<BlockPointerType>(LHSType)->getPointeeType(); 5714 rhptee = cast<BlockPointerType>(RHSType)->getPointeeType(); 5715 5716 // In C++, the types have to match exactly. 5717 if (S.getLangOpts().CPlusPlus) 5718 return Sema::IncompatibleBlockPointer; 5719 5720 Sema::AssignConvertType ConvTy = Sema::Compatible; 5721 5722 // For blocks we enforce that qualifiers are identical. 5723 if (lhptee.getLocalQualifiers() != rhptee.getLocalQualifiers()) 5724 ConvTy = Sema::CompatiblePointerDiscardsQualifiers; 5725 5726 if (!S.Context.typesAreBlockPointerCompatible(LHSType, RHSType)) 5727 return Sema::IncompatibleBlockPointer; 5728 5729 return ConvTy; 5730} 5731 5732/// checkObjCPointerTypesForAssignment - Compares two objective-c pointer types 5733/// for assignment compatibility. 5734static Sema::AssignConvertType 5735checkObjCPointerTypesForAssignment(Sema &S, QualType LHSType, 5736 QualType RHSType) { 5737 assert(LHSType.isCanonical() && "LHS was not canonicalized!"); 5738 assert(RHSType.isCanonical() && "RHS was not canonicalized!"); 5739 5740 if (LHSType->isObjCBuiltinType()) { 5741 // Class is not compatible with ObjC object pointers. 5742 if (LHSType->isObjCClassType() && !RHSType->isObjCBuiltinType() && 5743 !RHSType->isObjCQualifiedClassType()) 5744 return Sema::IncompatiblePointer; 5745 return Sema::Compatible; 5746 } 5747 if (RHSType->isObjCBuiltinType()) { 5748 if (RHSType->isObjCClassType() && !LHSType->isObjCBuiltinType() && 5749 !LHSType->isObjCQualifiedClassType()) 5750 return Sema::IncompatiblePointer; 5751 return Sema::Compatible; 5752 } 5753 QualType lhptee = LHSType->getAs<ObjCObjectPointerType>()->getPointeeType(); 5754 QualType rhptee = RHSType->getAs<ObjCObjectPointerType>()->getPointeeType(); 5755 5756 if (!lhptee.isAtLeastAsQualifiedAs(rhptee) && 5757 // make an exception for id<P> 5758 !LHSType->isObjCQualifiedIdType()) 5759 return Sema::CompatiblePointerDiscardsQualifiers; 5760 5761 if (S.Context.typesAreCompatible(LHSType, RHSType)) 5762 return Sema::Compatible; 5763 if (LHSType->isObjCQualifiedIdType() || RHSType->isObjCQualifiedIdType()) 5764 return Sema::IncompatibleObjCQualifiedId; 5765 return Sema::IncompatiblePointer; 5766} 5767 5768Sema::AssignConvertType 5769Sema::CheckAssignmentConstraints(SourceLocation Loc, 5770 QualType LHSType, QualType RHSType) { 5771 // Fake up an opaque expression. We don't actually care about what 5772 // cast operations are required, so if CheckAssignmentConstraints 5773 // adds casts to this they'll be wasted, but fortunately that doesn't 5774 // usually happen on valid code. 5775 OpaqueValueExpr RHSExpr(Loc, RHSType, VK_RValue); 5776 ExprResult RHSPtr = &RHSExpr; 5777 CastKind K = CK_Invalid; 5778 5779 return CheckAssignmentConstraints(LHSType, RHSPtr, K); 5780} 5781 5782/// CheckAssignmentConstraints (C99 6.5.16) - This routine currently 5783/// has code to accommodate several GCC extensions when type checking 5784/// pointers. Here are some objectionable examples that GCC considers warnings: 5785/// 5786/// int a, *pint; 5787/// short *pshort; 5788/// struct foo *pfoo; 5789/// 5790/// pint = pshort; // warning: assignment from incompatible pointer type 5791/// a = pint; // warning: assignment makes integer from pointer without a cast 5792/// pint = a; // warning: assignment makes pointer from integer without a cast 5793/// pint = pfoo; // warning: assignment from incompatible pointer type 5794/// 5795/// As a result, the code for dealing with pointers is more complex than the 5796/// C99 spec dictates. 5797/// 5798/// Sets 'Kind' for any result kind except Incompatible. 5799Sema::AssignConvertType 5800Sema::CheckAssignmentConstraints(QualType LHSType, ExprResult &RHS, 5801 CastKind &Kind) { 5802 QualType RHSType = RHS.get()->getType(); 5803 QualType OrigLHSType = LHSType; 5804 5805 // Get canonical types. We're not formatting these types, just comparing 5806 // them. 5807 LHSType = Context.getCanonicalType(LHSType).getUnqualifiedType(); 5808 RHSType = Context.getCanonicalType(RHSType).getUnqualifiedType(); 5809 5810 // Common case: no conversion required. 5811 if (LHSType == RHSType) { 5812 Kind = CK_NoOp; 5813 return Compatible; 5814 } 5815 5816 // If we have an atomic type, try a non-atomic assignment, then just add an 5817 // atomic qualification step. 5818 if (const AtomicType *AtomicTy = dyn_cast<AtomicType>(LHSType)) { 5819 Sema::AssignConvertType result = 5820 CheckAssignmentConstraints(AtomicTy->getValueType(), RHS, Kind); 5821 if (result != Compatible) 5822 return result; 5823 if (Kind != CK_NoOp) 5824 RHS = ImpCastExprToType(RHS.take(), AtomicTy->getValueType(), Kind); 5825 Kind = CK_NonAtomicToAtomic; 5826 return Compatible; 5827 } 5828 5829 // If the left-hand side is a reference type, then we are in a 5830 // (rare!) case where we've allowed the use of references in C, 5831 // e.g., as a parameter type in a built-in function. In this case, 5832 // just make sure that the type referenced is compatible with the 5833 // right-hand side type. The caller is responsible for adjusting 5834 // LHSType so that the resulting expression does not have reference 5835 // type. 5836 if (const ReferenceType *LHSTypeRef = LHSType->getAs<ReferenceType>()) { 5837 if (Context.typesAreCompatible(LHSTypeRef->getPointeeType(), RHSType)) { 5838 Kind = CK_LValueBitCast; 5839 return Compatible; 5840 } 5841 return Incompatible; 5842 } 5843 5844 // Allow scalar to ExtVector assignments, and assignments of an ExtVector type 5845 // to the same ExtVector type. 5846 if (LHSType->isExtVectorType()) { 5847 if (RHSType->isExtVectorType()) 5848 return Incompatible; 5849 if (RHSType->isArithmeticType()) { 5850 // CK_VectorSplat does T -> vector T, so first cast to the 5851 // element type. 5852 QualType elType = cast<ExtVectorType>(LHSType)->getElementType(); 5853 if (elType != RHSType) { 5854 Kind = PrepareScalarCast(RHS, elType); 5855 RHS = ImpCastExprToType(RHS.take(), elType, Kind); 5856 } 5857 Kind = CK_VectorSplat; 5858 return Compatible; 5859 } 5860 } 5861 5862 // Conversions to or from vector type. 5863 if (LHSType->isVectorType() || RHSType->isVectorType()) { 5864 if (LHSType->isVectorType() && RHSType->isVectorType()) { 5865 // Allow assignments of an AltiVec vector type to an equivalent GCC 5866 // vector type and vice versa 5867 if (Context.areCompatibleVectorTypes(LHSType, RHSType)) { 5868 Kind = CK_BitCast; 5869 return Compatible; 5870 } 5871 5872 // If we are allowing lax vector conversions, and LHS and RHS are both 5873 // vectors, the total size only needs to be the same. This is a bitcast; 5874 // no bits are changed but the result type is different. 5875 if (getLangOpts().LaxVectorConversions && 5876 (Context.getTypeSize(LHSType) == Context.getTypeSize(RHSType))) { 5877 Kind = CK_BitCast; 5878 return IncompatibleVectors; 5879 } 5880 } 5881 return Incompatible; 5882 } 5883 5884 // Arithmetic conversions. 5885 if (LHSType->isArithmeticType() && RHSType->isArithmeticType() && 5886 !(getLangOpts().CPlusPlus && LHSType->isEnumeralType())) { 5887 Kind = PrepareScalarCast(RHS, LHSType); 5888 return Compatible; 5889 } 5890 5891 // Conversions to normal pointers. 5892 if (const PointerType *LHSPointer = dyn_cast<PointerType>(LHSType)) { 5893 // U* -> T* 5894 if (isa<PointerType>(RHSType)) { 5895 Kind = CK_BitCast; 5896 return checkPointerTypesForAssignment(*this, LHSType, RHSType); 5897 } 5898 5899 // int -> T* 5900 if (RHSType->isIntegerType()) { 5901 Kind = CK_IntegralToPointer; // FIXME: null? 5902 return IntToPointer; 5903 } 5904 5905 // C pointers are not compatible with ObjC object pointers, 5906 // with two exceptions: 5907 if (isa<ObjCObjectPointerType>(RHSType)) { 5908 // - conversions to void* 5909 if (LHSPointer->getPointeeType()->isVoidType()) { 5910 Kind = CK_BitCast; 5911 return Compatible; 5912 } 5913 5914 // - conversions from 'Class' to the redefinition type 5915 if (RHSType->isObjCClassType() && 5916 Context.hasSameType(LHSType, 5917 Context.getObjCClassRedefinitionType())) { 5918 Kind = CK_BitCast; 5919 return Compatible; 5920 } 5921 5922 Kind = CK_BitCast; 5923 return IncompatiblePointer; 5924 } 5925 5926 // U^ -> void* 5927 if (RHSType->getAs<BlockPointerType>()) { 5928 if (LHSPointer->getPointeeType()->isVoidType()) { 5929 Kind = CK_BitCast; 5930 return Compatible; 5931 } 5932 } 5933 5934 return Incompatible; 5935 } 5936 5937 // Conversions to block pointers. 5938 if (isa<BlockPointerType>(LHSType)) { 5939 // U^ -> T^ 5940 if (RHSType->isBlockPointerType()) { 5941 Kind = CK_BitCast; 5942 return checkBlockPointerTypesForAssignment(*this, LHSType, RHSType); 5943 } 5944 5945 // int or null -> T^ 5946 if (RHSType->isIntegerType()) { 5947 Kind = CK_IntegralToPointer; // FIXME: null 5948 return IntToBlockPointer; 5949 } 5950 5951 // id -> T^ 5952 if (getLangOpts().ObjC1 && RHSType->isObjCIdType()) { 5953 Kind = CK_AnyPointerToBlockPointerCast; 5954 return Compatible; 5955 } 5956 5957 // void* -> T^ 5958 if (const PointerType *RHSPT = RHSType->getAs<PointerType>()) 5959 if (RHSPT->getPointeeType()->isVoidType()) { 5960 Kind = CK_AnyPointerToBlockPointerCast; 5961 return Compatible; 5962 } 5963 5964 return Incompatible; 5965 } 5966 5967 // Conversions to Objective-C pointers. 5968 if (isa<ObjCObjectPointerType>(LHSType)) { 5969 // A* -> B* 5970 if (RHSType->isObjCObjectPointerType()) { 5971 Kind = CK_BitCast; 5972 Sema::AssignConvertType result = 5973 checkObjCPointerTypesForAssignment(*this, LHSType, RHSType); 5974 if (getLangOpts().ObjCAutoRefCount && 5975 result == Compatible && 5976 !CheckObjCARCUnavailableWeakConversion(OrigLHSType, RHSType)) 5977 result = IncompatibleObjCWeakRef; 5978 return result; 5979 } 5980 5981 // int or null -> A* 5982 if (RHSType->isIntegerType()) { 5983 Kind = CK_IntegralToPointer; // FIXME: null 5984 return IntToPointer; 5985 } 5986 5987 // In general, C pointers are not compatible with ObjC object pointers, 5988 // with two exceptions: 5989 if (isa<PointerType>(RHSType)) { 5990 Kind = CK_CPointerToObjCPointerCast; 5991 5992 // - conversions from 'void*' 5993 if (RHSType->isVoidPointerType()) { 5994 return Compatible; 5995 } 5996 5997 // - conversions to 'Class' from its redefinition type 5998 if (LHSType->isObjCClassType() && 5999 Context.hasSameType(RHSType, 6000 Context.getObjCClassRedefinitionType())) { 6001 return Compatible; 6002 } 6003 6004 return IncompatiblePointer; 6005 } 6006 6007 // T^ -> A* 6008 if (RHSType->isBlockPointerType()) { 6009 maybeExtendBlockObject(*this, RHS); 6010 Kind = CK_BlockPointerToObjCPointerCast; 6011 return Compatible; 6012 } 6013 6014 return Incompatible; 6015 } 6016 6017 // Conversions from pointers that are not covered by the above. 6018 if (isa<PointerType>(RHSType)) { 6019 // T* -> _Bool 6020 if (LHSType == Context.BoolTy) { 6021 Kind = CK_PointerToBoolean; 6022 return Compatible; 6023 } 6024 6025 // T* -> int 6026 if (LHSType->isIntegerType()) { 6027 Kind = CK_PointerToIntegral; 6028 return PointerToInt; 6029 } 6030 6031 return Incompatible; 6032 } 6033 6034 // Conversions from Objective-C pointers that are not covered by the above. 6035 if (isa<ObjCObjectPointerType>(RHSType)) { 6036 // T* -> _Bool 6037 if (LHSType == Context.BoolTy) { 6038 Kind = CK_PointerToBoolean; 6039 return Compatible; 6040 } 6041 6042 // T* -> int 6043 if (LHSType->isIntegerType()) { 6044 Kind = CK_PointerToIntegral; 6045 return PointerToInt; 6046 } 6047 6048 return Incompatible; 6049 } 6050 6051 // struct A -> struct B 6052 if (isa<TagType>(LHSType) && isa<TagType>(RHSType)) { 6053 if (Context.typesAreCompatible(LHSType, RHSType)) { 6054 Kind = CK_NoOp; 6055 return Compatible; 6056 } 6057 } 6058 6059 return Incompatible; 6060} 6061 6062/// \brief Constructs a transparent union from an expression that is 6063/// used to initialize the transparent union. 6064static void ConstructTransparentUnion(Sema &S, ASTContext &C, 6065 ExprResult &EResult, QualType UnionType, 6066 FieldDecl *Field) { 6067 // Build an initializer list that designates the appropriate member 6068 // of the transparent union. 6069 Expr *E = EResult.take(); 6070 InitListExpr *Initializer = new (C) InitListExpr(C, SourceLocation(), 6071 E, SourceLocation()); 6072 Initializer->setType(UnionType); 6073 Initializer->setInitializedFieldInUnion(Field); 6074 6075 // Build a compound literal constructing a value of the transparent 6076 // union type from this initializer list. 6077 TypeSourceInfo *unionTInfo = C.getTrivialTypeSourceInfo(UnionType); 6078 EResult = S.Owned( 6079 new (C) CompoundLiteralExpr(SourceLocation(), unionTInfo, UnionType, 6080 VK_RValue, Initializer, false)); 6081} 6082 6083Sema::AssignConvertType 6084Sema::CheckTransparentUnionArgumentConstraints(QualType ArgType, 6085 ExprResult &RHS) { 6086 QualType RHSType = RHS.get()->getType(); 6087 6088 // If the ArgType is a Union type, we want to handle a potential 6089 // transparent_union GCC extension. 6090 const RecordType *UT = ArgType->getAsUnionType(); 6091 if (!UT || !UT->getDecl()->hasAttr<TransparentUnionAttr>()) 6092 return Incompatible; 6093 6094 // The field to initialize within the transparent union. 6095 RecordDecl *UD = UT->getDecl(); 6096 FieldDecl *InitField = 0; 6097 // It's compatible if the expression matches any of the fields. 6098 for (RecordDecl::field_iterator it = UD->field_begin(), 6099 itend = UD->field_end(); 6100 it != itend; ++it) { 6101 if (it->getType()->isPointerType()) { 6102 // If the transparent union contains a pointer type, we allow: 6103 // 1) void pointer 6104 // 2) null pointer constant 6105 if (RHSType->isPointerType()) 6106 if (RHSType->castAs<PointerType>()->getPointeeType()->isVoidType()) { 6107 RHS = ImpCastExprToType(RHS.take(), it->getType(), CK_BitCast); 6108 InitField = *it; 6109 break; 6110 } 6111 6112 if (RHS.get()->isNullPointerConstant(Context, 6113 Expr::NPC_ValueDependentIsNull)) { 6114 RHS = ImpCastExprToType(RHS.take(), it->getType(), 6115 CK_NullToPointer); 6116 InitField = *it; 6117 break; 6118 } 6119 } 6120 6121 CastKind Kind = CK_Invalid; 6122 if (CheckAssignmentConstraints(it->getType(), RHS, Kind) 6123 == Compatible) { 6124 RHS = ImpCastExprToType(RHS.take(), it->getType(), Kind); 6125 InitField = *it; 6126 break; 6127 } 6128 } 6129 6130 if (!InitField) 6131 return Incompatible; 6132 6133 ConstructTransparentUnion(*this, Context, RHS, ArgType, InitField); 6134 return Compatible; 6135} 6136 6137Sema::AssignConvertType 6138Sema::CheckSingleAssignmentConstraints(QualType LHSType, ExprResult &RHS, 6139 bool Diagnose) { 6140 if (getLangOpts().CPlusPlus) { 6141 if (!LHSType->isRecordType() && !LHSType->isAtomicType()) { 6142 // C++ 5.17p3: If the left operand is not of class type, the 6143 // expression is implicitly converted (C++ 4) to the 6144 // cv-unqualified type of the left operand. 6145 ExprResult Res; 6146 if (Diagnose) { 6147 Res = PerformImplicitConversion(RHS.get(), LHSType.getUnqualifiedType(), 6148 AA_Assigning); 6149 } else { 6150 ImplicitConversionSequence ICS = 6151 TryImplicitConversion(RHS.get(), LHSType.getUnqualifiedType(), 6152 /*SuppressUserConversions=*/false, 6153 /*AllowExplicit=*/false, 6154 /*InOverloadResolution=*/false, 6155 /*CStyle=*/false, 6156 /*AllowObjCWritebackConversion=*/false); 6157 if (ICS.isFailure()) 6158 return Incompatible; 6159 Res = PerformImplicitConversion(RHS.get(), LHSType.getUnqualifiedType(), 6160 ICS, AA_Assigning); 6161 } 6162 if (Res.isInvalid()) 6163 return Incompatible; 6164 Sema::AssignConvertType result = Compatible; 6165 if (getLangOpts().ObjCAutoRefCount && 6166 !CheckObjCARCUnavailableWeakConversion(LHSType, 6167 RHS.get()->getType())) 6168 result = IncompatibleObjCWeakRef; 6169 RHS = Res; 6170 return result; 6171 } 6172 6173 // FIXME: Currently, we fall through and treat C++ classes like C 6174 // structures. 6175 // FIXME: We also fall through for atomics; not sure what should 6176 // happen there, though. 6177 } 6178 6179 // C99 6.5.16.1p1: the left operand is a pointer and the right is 6180 // a null pointer constant. 6181 if ((LHSType->isPointerType() || 6182 LHSType->isObjCObjectPointerType() || 6183 LHSType->isBlockPointerType()) 6184 && RHS.get()->isNullPointerConstant(Context, 6185 Expr::NPC_ValueDependentIsNull)) { 6186 RHS = ImpCastExprToType(RHS.take(), LHSType, CK_NullToPointer); 6187 return Compatible; 6188 } 6189 6190 // This check seems unnatural, however it is necessary to ensure the proper 6191 // conversion of functions/arrays. If the conversion were done for all 6192 // DeclExpr's (created by ActOnIdExpression), it would mess up the unary 6193 // expressions that suppress this implicit conversion (&, sizeof). 6194 // 6195 // Suppress this for references: C++ 8.5.3p5. 6196 if (!LHSType->isReferenceType()) { 6197 RHS = DefaultFunctionArrayLvalueConversion(RHS.take()); 6198 if (RHS.isInvalid()) 6199 return Incompatible; 6200 } 6201 6202 CastKind Kind = CK_Invalid; 6203 Sema::AssignConvertType result = 6204 CheckAssignmentConstraints(LHSType, RHS, Kind); 6205 6206 // C99 6.5.16.1p2: The value of the right operand is converted to the 6207 // type of the assignment expression. 6208 // CheckAssignmentConstraints allows the left-hand side to be a reference, 6209 // so that we can use references in built-in functions even in C. 6210 // The getNonReferenceType() call makes sure that the resulting expression 6211 // does not have reference type. 6212 if (result != Incompatible && RHS.get()->getType() != LHSType) 6213 RHS = ImpCastExprToType(RHS.take(), 6214 LHSType.getNonLValueExprType(Context), Kind); 6215 return result; 6216} 6217 6218QualType Sema::InvalidOperands(SourceLocation Loc, ExprResult &LHS, 6219 ExprResult &RHS) { 6220 Diag(Loc, diag::err_typecheck_invalid_operands) 6221 << LHS.get()->getType() << RHS.get()->getType() 6222 << LHS.get()->getSourceRange() << RHS.get()->getSourceRange(); 6223 return QualType(); 6224} 6225 6226QualType Sema::CheckVectorOperands(ExprResult &LHS, ExprResult &RHS, 6227 SourceLocation Loc, bool IsCompAssign) { 6228 if (!IsCompAssign) { 6229 LHS = DefaultFunctionArrayLvalueConversion(LHS.take()); 6230 if (LHS.isInvalid()) 6231 return QualType(); 6232 } 6233 RHS = DefaultFunctionArrayLvalueConversion(RHS.take()); 6234 if (RHS.isInvalid()) 6235 return QualType(); 6236 6237 // For conversion purposes, we ignore any qualifiers. 6238 // For example, "const float" and "float" are equivalent. 6239 QualType LHSType = 6240 Context.getCanonicalType(LHS.get()->getType()).getUnqualifiedType(); 6241 QualType RHSType = 6242 Context.getCanonicalType(RHS.get()->getType()).getUnqualifiedType(); 6243 6244 // If the vector types are identical, return. 6245 if (LHSType == RHSType) 6246 return LHSType; 6247 6248 // Handle the case of equivalent AltiVec and GCC vector types 6249 if (LHSType->isVectorType() && RHSType->isVectorType() && 6250 Context.areCompatibleVectorTypes(LHSType, RHSType)) { 6251 if (LHSType->isExtVectorType()) { 6252 RHS = ImpCastExprToType(RHS.take(), LHSType, CK_BitCast); 6253 return LHSType; 6254 } 6255 6256 if (!IsCompAssign) 6257 LHS = ImpCastExprToType(LHS.take(), RHSType, CK_BitCast); 6258 return RHSType; 6259 } 6260 6261 if (getLangOpts().LaxVectorConversions && 6262 Context.getTypeSize(LHSType) == Context.getTypeSize(RHSType)) { 6263 // If we are allowing lax vector conversions, and LHS and RHS are both 6264 // vectors, the total size only needs to be the same. This is a 6265 // bitcast; no bits are changed but the result type is different. 6266 // FIXME: Should we really be allowing this? 6267 RHS = ImpCastExprToType(RHS.take(), LHSType, CK_BitCast); 6268 return LHSType; 6269 } 6270 6271 // Canonicalize the ExtVector to the LHS, remember if we swapped so we can 6272 // swap back (so that we don't reverse the inputs to a subtract, for instance. 6273 bool swapped = false; 6274 if (RHSType->isExtVectorType() && !IsCompAssign) { 6275 swapped = true; 6276 std::swap(RHS, LHS); 6277 std::swap(RHSType, LHSType); 6278 } 6279 6280 // Handle the case of an ext vector and scalar. 6281 if (const ExtVectorType *LV = LHSType->getAs<ExtVectorType>()) { 6282 QualType EltTy = LV->getElementType(); 6283 if (EltTy->isIntegralType(Context) && RHSType->isIntegralType(Context)) { 6284 int order = Context.getIntegerTypeOrder(EltTy, RHSType); 6285 if (order > 0) 6286 RHS = ImpCastExprToType(RHS.take(), EltTy, CK_IntegralCast); 6287 if (order >= 0) { 6288 RHS = ImpCastExprToType(RHS.take(), LHSType, CK_VectorSplat); 6289 if (swapped) std::swap(RHS, LHS); 6290 return LHSType; 6291 } 6292 } 6293 if (EltTy->isRealFloatingType() && RHSType->isScalarType() && 6294 RHSType->isRealFloatingType()) { 6295 int order = Context.getFloatingTypeOrder(EltTy, RHSType); 6296 if (order > 0) 6297 RHS = ImpCastExprToType(RHS.take(), EltTy, CK_FloatingCast); 6298 if (order >= 0) { 6299 RHS = ImpCastExprToType(RHS.take(), LHSType, CK_VectorSplat); 6300 if (swapped) std::swap(RHS, LHS); 6301 return LHSType; 6302 } 6303 } 6304 } 6305 6306 // Vectors of different size or scalar and non-ext-vector are errors. 6307 if (swapped) std::swap(RHS, LHS); 6308 Diag(Loc, diag::err_typecheck_vector_not_convertable) 6309 << LHS.get()->getType() << RHS.get()->getType() 6310 << LHS.get()->getSourceRange() << RHS.get()->getSourceRange(); 6311 return QualType(); 6312} 6313 6314// checkArithmeticNull - Detect when a NULL constant is used improperly in an 6315// expression. These are mainly cases where the null pointer is used as an 6316// integer instead of a pointer. 6317static void checkArithmeticNull(Sema &S, ExprResult &LHS, ExprResult &RHS, 6318 SourceLocation Loc, bool IsCompare) { 6319 // The canonical way to check for a GNU null is with isNullPointerConstant, 6320 // but we use a bit of a hack here for speed; this is a relatively 6321 // hot path, and isNullPointerConstant is slow. 6322 bool LHSNull = isa<GNUNullExpr>(LHS.get()->IgnoreParenImpCasts()); 6323 bool RHSNull = isa<GNUNullExpr>(RHS.get()->IgnoreParenImpCasts()); 6324 6325 QualType NonNullType = LHSNull ? RHS.get()->getType() : LHS.get()->getType(); 6326 6327 // Avoid analyzing cases where the result will either be invalid (and 6328 // diagnosed as such) or entirely valid and not something to warn about. 6329 if ((!LHSNull && !RHSNull) || NonNullType->isBlockPointerType() || 6330 NonNullType->isMemberPointerType() || NonNullType->isFunctionType()) 6331 return; 6332 6333 // Comparison operations would not make sense with a null pointer no matter 6334 // what the other expression is. 6335 if (!IsCompare) { 6336 S.Diag(Loc, diag::warn_null_in_arithmetic_operation) 6337 << (LHSNull ? LHS.get()->getSourceRange() : SourceRange()) 6338 << (RHSNull ? RHS.get()->getSourceRange() : SourceRange()); 6339 return; 6340 } 6341 6342 // The rest of the operations only make sense with a null pointer 6343 // if the other expression is a pointer. 6344 if (LHSNull == RHSNull || NonNullType->isAnyPointerType() || 6345 NonNullType->canDecayToPointerType()) 6346 return; 6347 6348 S.Diag(Loc, diag::warn_null_in_comparison_operation) 6349 << LHSNull /* LHS is NULL */ << NonNullType 6350 << LHS.get()->getSourceRange() << RHS.get()->getSourceRange(); 6351} 6352 6353QualType Sema::CheckMultiplyDivideOperands(ExprResult &LHS, ExprResult &RHS, 6354 SourceLocation Loc, 6355 bool IsCompAssign, bool IsDiv) { 6356 checkArithmeticNull(*this, LHS, RHS, Loc, /*isCompare=*/false); 6357 6358 if (LHS.get()->getType()->isVectorType() || 6359 RHS.get()->getType()->isVectorType()) 6360 return CheckVectorOperands(LHS, RHS, Loc, IsCompAssign); 6361 6362 QualType compType = UsualArithmeticConversions(LHS, RHS, IsCompAssign); 6363 if (LHS.isInvalid() || RHS.isInvalid()) 6364 return QualType(); 6365 6366 6367 if (compType.isNull() || !compType->isArithmeticType()) 6368 return InvalidOperands(Loc, LHS, RHS); 6369 6370 // Check for division by zero. 6371 if (IsDiv && 6372 RHS.get()->isNullPointerConstant(Context, 6373 Expr::NPC_ValueDependentIsNotNull)) 6374 DiagRuntimeBehavior(Loc, RHS.get(), PDiag(diag::warn_division_by_zero) 6375 << RHS.get()->getSourceRange()); 6376 6377 return compType; 6378} 6379 6380QualType Sema::CheckRemainderOperands( 6381 ExprResult &LHS, ExprResult &RHS, SourceLocation Loc, bool IsCompAssign) { 6382 checkArithmeticNull(*this, LHS, RHS, Loc, /*isCompare=*/false); 6383 6384 if (LHS.get()->getType()->isVectorType() || 6385 RHS.get()->getType()->isVectorType()) { 6386 if (LHS.get()->getType()->hasIntegerRepresentation() && 6387 RHS.get()->getType()->hasIntegerRepresentation()) 6388 return CheckVectorOperands(LHS, RHS, Loc, IsCompAssign); 6389 return InvalidOperands(Loc, LHS, RHS); 6390 } 6391 6392 QualType compType = UsualArithmeticConversions(LHS, RHS, IsCompAssign); 6393 if (LHS.isInvalid() || RHS.isInvalid()) 6394 return QualType(); 6395 6396 if (compType.isNull() || !compType->isIntegerType()) 6397 return InvalidOperands(Loc, LHS, RHS); 6398 6399 // Check for remainder by zero. 6400 if (RHS.get()->isNullPointerConstant(Context, 6401 Expr::NPC_ValueDependentIsNotNull)) 6402 DiagRuntimeBehavior(Loc, RHS.get(), PDiag(diag::warn_remainder_by_zero) 6403 << RHS.get()->getSourceRange()); 6404 6405 return compType; 6406} 6407 6408/// \brief Diagnose invalid arithmetic on two void pointers. 6409static void diagnoseArithmeticOnTwoVoidPointers(Sema &S, SourceLocation Loc, 6410 Expr *LHSExpr, Expr *RHSExpr) { 6411 S.Diag(Loc, S.getLangOpts().CPlusPlus 6412 ? diag::err_typecheck_pointer_arith_void_type 6413 : diag::ext_gnu_void_ptr) 6414 << 1 /* two pointers */ << LHSExpr->getSourceRange() 6415 << RHSExpr->getSourceRange(); 6416} 6417 6418/// \brief Diagnose invalid arithmetic on a void pointer. 6419static void diagnoseArithmeticOnVoidPointer(Sema &S, SourceLocation Loc, 6420 Expr *Pointer) { 6421 S.Diag(Loc, S.getLangOpts().CPlusPlus 6422 ? diag::err_typecheck_pointer_arith_void_type 6423 : diag::ext_gnu_void_ptr) 6424 << 0 /* one pointer */ << Pointer->getSourceRange(); 6425} 6426 6427/// \brief Diagnose invalid arithmetic on two function pointers. 6428static void diagnoseArithmeticOnTwoFunctionPointers(Sema &S, SourceLocation Loc, 6429 Expr *LHS, Expr *RHS) { 6430 assert(LHS->getType()->isAnyPointerType()); 6431 assert(RHS->getType()->isAnyPointerType()); 6432 S.Diag(Loc, S.getLangOpts().CPlusPlus 6433 ? diag::err_typecheck_pointer_arith_function_type 6434 : diag::ext_gnu_ptr_func_arith) 6435 << 1 /* two pointers */ << LHS->getType()->getPointeeType() 6436 // We only show the second type if it differs from the first. 6437 << (unsigned)!S.Context.hasSameUnqualifiedType(LHS->getType(), 6438 RHS->getType()) 6439 << RHS->getType()->getPointeeType() 6440 << LHS->getSourceRange() << RHS->getSourceRange(); 6441} 6442 6443/// \brief Diagnose invalid arithmetic on a function pointer. 6444static void diagnoseArithmeticOnFunctionPointer(Sema &S, SourceLocation Loc, 6445 Expr *Pointer) { 6446 assert(Pointer->getType()->isAnyPointerType()); 6447 S.Diag(Loc, S.getLangOpts().CPlusPlus 6448 ? diag::err_typecheck_pointer_arith_function_type 6449 : diag::ext_gnu_ptr_func_arith) 6450 << 0 /* one pointer */ << Pointer->getType()->getPointeeType() 6451 << 0 /* one pointer, so only one type */ 6452 << Pointer->getSourceRange(); 6453} 6454 6455/// \brief Emit error if Operand is incomplete pointer type 6456/// 6457/// \returns True if pointer has incomplete type 6458static bool checkArithmeticIncompletePointerType(Sema &S, SourceLocation Loc, 6459 Expr *Operand) { 6460 assert(Operand->getType()->isAnyPointerType() && 6461 !Operand->getType()->isDependentType()); 6462 QualType PointeeTy = Operand->getType()->getPointeeType(); 6463 return S.RequireCompleteType(Loc, PointeeTy, 6464 diag::err_typecheck_arithmetic_incomplete_type, 6465 PointeeTy, Operand->getSourceRange()); 6466} 6467 6468/// \brief Check the validity of an arithmetic pointer operand. 6469/// 6470/// If the operand has pointer type, this code will check for pointer types 6471/// which are invalid in arithmetic operations. These will be diagnosed 6472/// appropriately, including whether or not the use is supported as an 6473/// extension. 6474/// 6475/// \returns True when the operand is valid to use (even if as an extension). 6476static bool checkArithmeticOpPointerOperand(Sema &S, SourceLocation Loc, 6477 Expr *Operand) { 6478 if (!Operand->getType()->isAnyPointerType()) return true; 6479 6480 QualType PointeeTy = Operand->getType()->getPointeeType(); 6481 if (PointeeTy->isVoidType()) { 6482 diagnoseArithmeticOnVoidPointer(S, Loc, Operand); 6483 return !S.getLangOpts().CPlusPlus; 6484 } 6485 if (PointeeTy->isFunctionType()) { 6486 diagnoseArithmeticOnFunctionPointer(S, Loc, Operand); 6487 return !S.getLangOpts().CPlusPlus; 6488 } 6489 6490 if (checkArithmeticIncompletePointerType(S, Loc, Operand)) return false; 6491 6492 return true; 6493} 6494 6495/// \brief Check the validity of a binary arithmetic operation w.r.t. pointer 6496/// operands. 6497/// 6498/// This routine will diagnose any invalid arithmetic on pointer operands much 6499/// like \see checkArithmeticOpPointerOperand. However, it has special logic 6500/// for emitting a single diagnostic even for operations where both LHS and RHS 6501/// are (potentially problematic) pointers. 6502/// 6503/// \returns True when the operand is valid to use (even if as an extension). 6504static bool checkArithmeticBinOpPointerOperands(Sema &S, SourceLocation Loc, 6505 Expr *LHSExpr, Expr *RHSExpr) { 6506 bool isLHSPointer = LHSExpr->getType()->isAnyPointerType(); 6507 bool isRHSPointer = RHSExpr->getType()->isAnyPointerType(); 6508 if (!isLHSPointer && !isRHSPointer) return true; 6509 6510 QualType LHSPointeeTy, RHSPointeeTy; 6511 if (isLHSPointer) LHSPointeeTy = LHSExpr->getType()->getPointeeType(); 6512 if (isRHSPointer) RHSPointeeTy = RHSExpr->getType()->getPointeeType(); 6513 6514 // Check for arithmetic on pointers to incomplete types. 6515 bool isLHSVoidPtr = isLHSPointer && LHSPointeeTy->isVoidType(); 6516 bool isRHSVoidPtr = isRHSPointer && RHSPointeeTy->isVoidType(); 6517 if (isLHSVoidPtr || isRHSVoidPtr) { 6518 if (!isRHSVoidPtr) diagnoseArithmeticOnVoidPointer(S, Loc, LHSExpr); 6519 else if (!isLHSVoidPtr) diagnoseArithmeticOnVoidPointer(S, Loc, RHSExpr); 6520 else diagnoseArithmeticOnTwoVoidPointers(S, Loc, LHSExpr, RHSExpr); 6521 6522 return !S.getLangOpts().CPlusPlus; 6523 } 6524 6525 bool isLHSFuncPtr = isLHSPointer && LHSPointeeTy->isFunctionType(); 6526 bool isRHSFuncPtr = isRHSPointer && RHSPointeeTy->isFunctionType(); 6527 if (isLHSFuncPtr || isRHSFuncPtr) { 6528 if (!isRHSFuncPtr) diagnoseArithmeticOnFunctionPointer(S, Loc, LHSExpr); 6529 else if (!isLHSFuncPtr) diagnoseArithmeticOnFunctionPointer(S, Loc, 6530 RHSExpr); 6531 else diagnoseArithmeticOnTwoFunctionPointers(S, Loc, LHSExpr, RHSExpr); 6532 6533 return !S.getLangOpts().CPlusPlus; 6534 } 6535 6536 if (isLHSPointer && checkArithmeticIncompletePointerType(S, Loc, LHSExpr)) 6537 return false; 6538 if (isRHSPointer && checkArithmeticIncompletePointerType(S, Loc, RHSExpr)) 6539 return false; 6540 6541 return true; 6542} 6543 6544/// diagnoseStringPlusInt - Emit a warning when adding an integer to a string 6545/// literal. 6546static void diagnoseStringPlusInt(Sema &Self, SourceLocation OpLoc, 6547 Expr *LHSExpr, Expr *RHSExpr) { 6548 StringLiteral* StrExpr = dyn_cast<StringLiteral>(LHSExpr->IgnoreImpCasts()); 6549 Expr* IndexExpr = RHSExpr; 6550 if (!StrExpr) { 6551 StrExpr = dyn_cast<StringLiteral>(RHSExpr->IgnoreImpCasts()); 6552 IndexExpr = LHSExpr; 6553 } 6554 6555 bool IsStringPlusInt = StrExpr && 6556 IndexExpr->getType()->isIntegralOrUnscopedEnumerationType(); 6557 if (!IsStringPlusInt) 6558 return; 6559 6560 llvm::APSInt index; 6561 if (IndexExpr->EvaluateAsInt(index, Self.getASTContext())) { 6562 unsigned StrLenWithNull = StrExpr->getLength() + 1; 6563 if (index.isNonNegative() && 6564 index <= llvm::APSInt(llvm::APInt(index.getBitWidth(), StrLenWithNull), 6565 index.isUnsigned())) 6566 return; 6567 } 6568 6569 SourceRange DiagRange(LHSExpr->getLocStart(), RHSExpr->getLocEnd()); 6570 Self.Diag(OpLoc, diag::warn_string_plus_int) 6571 << DiagRange << IndexExpr->IgnoreImpCasts()->getType(); 6572 6573 // Only print a fixit for "str" + int, not for int + "str". 6574 if (IndexExpr == RHSExpr) { 6575 SourceLocation EndLoc = Self.PP.getLocForEndOfToken(RHSExpr->getLocEnd()); 6576 Self.Diag(OpLoc, diag::note_string_plus_int_silence) 6577 << FixItHint::CreateInsertion(LHSExpr->getLocStart(), "&") 6578 << FixItHint::CreateReplacement(SourceRange(OpLoc), "[") 6579 << FixItHint::CreateInsertion(EndLoc, "]"); 6580 } else 6581 Self.Diag(OpLoc, diag::note_string_plus_int_silence); 6582} 6583 6584/// \brief Emit error when two pointers are incompatible. 6585static void diagnosePointerIncompatibility(Sema &S, SourceLocation Loc, 6586 Expr *LHSExpr, Expr *RHSExpr) { 6587 assert(LHSExpr->getType()->isAnyPointerType()); 6588 assert(RHSExpr->getType()->isAnyPointerType()); 6589 S.Diag(Loc, diag::err_typecheck_sub_ptr_compatible) 6590 << LHSExpr->getType() << RHSExpr->getType() << LHSExpr->getSourceRange() 6591 << RHSExpr->getSourceRange(); 6592} 6593 6594QualType Sema::CheckAdditionOperands( // C99 6.5.6 6595 ExprResult &LHS, ExprResult &RHS, SourceLocation Loc, unsigned Opc, 6596 QualType* CompLHSTy) { 6597 checkArithmeticNull(*this, LHS, RHS, Loc, /*isCompare=*/false); 6598 6599 if (LHS.get()->getType()->isVectorType() || 6600 RHS.get()->getType()->isVectorType()) { 6601 QualType compType = CheckVectorOperands(LHS, RHS, Loc, CompLHSTy); 6602 if (CompLHSTy) *CompLHSTy = compType; 6603 return compType; 6604 } 6605 6606 QualType compType = UsualArithmeticConversions(LHS, RHS, CompLHSTy); 6607 if (LHS.isInvalid() || RHS.isInvalid()) 6608 return QualType(); 6609 6610 // Diagnose "string literal" '+' int. 6611 if (Opc == BO_Add) 6612 diagnoseStringPlusInt(*this, Loc, LHS.get(), RHS.get()); 6613 6614 // handle the common case first (both operands are arithmetic). 6615 if (!compType.isNull() && compType->isArithmeticType()) { 6616 if (CompLHSTy) *CompLHSTy = compType; 6617 return compType; 6618 } 6619 6620 // Type-checking. Ultimately the pointer's going to be in PExp; 6621 // note that we bias towards the LHS being the pointer. 6622 Expr *PExp = LHS.get(), *IExp = RHS.get(); 6623 6624 bool isObjCPointer; 6625 if (PExp->getType()->isPointerType()) { 6626 isObjCPointer = false; 6627 } else if (PExp->getType()->isObjCObjectPointerType()) { 6628 isObjCPointer = true; 6629 } else { 6630 std::swap(PExp, IExp); 6631 if (PExp->getType()->isPointerType()) { 6632 isObjCPointer = false; 6633 } else if (PExp->getType()->isObjCObjectPointerType()) { 6634 isObjCPointer = true; 6635 } else { 6636 return InvalidOperands(Loc, LHS, RHS); 6637 } 6638 } 6639 assert(PExp->getType()->isAnyPointerType()); 6640 6641 if (!IExp->getType()->isIntegerType()) 6642 return InvalidOperands(Loc, LHS, RHS); 6643 6644 if (!checkArithmeticOpPointerOperand(*this, Loc, PExp)) 6645 return QualType(); 6646 6647 if (isObjCPointer && checkArithmeticOnObjCPointer(*this, Loc, PExp)) 6648 return QualType(); 6649 6650 // Check array bounds for pointer arithemtic 6651 CheckArrayAccess(PExp, IExp); 6652 6653 if (CompLHSTy) { 6654 QualType LHSTy = Context.isPromotableBitField(LHS.get()); 6655 if (LHSTy.isNull()) { 6656 LHSTy = LHS.get()->getType(); 6657 if (LHSTy->isPromotableIntegerType()) 6658 LHSTy = Context.getPromotedIntegerType(LHSTy); 6659 } 6660 *CompLHSTy = LHSTy; 6661 } 6662 6663 return PExp->getType(); 6664} 6665 6666// C99 6.5.6 6667QualType Sema::CheckSubtractionOperands(ExprResult &LHS, ExprResult &RHS, 6668 SourceLocation Loc, 6669 QualType* CompLHSTy) { 6670 checkArithmeticNull(*this, LHS, RHS, Loc, /*isCompare=*/false); 6671 6672 if (LHS.get()->getType()->isVectorType() || 6673 RHS.get()->getType()->isVectorType()) { 6674 QualType compType = CheckVectorOperands(LHS, RHS, Loc, CompLHSTy); 6675 if (CompLHSTy) *CompLHSTy = compType; 6676 return compType; 6677 } 6678 6679 QualType compType = UsualArithmeticConversions(LHS, RHS, CompLHSTy); 6680 if (LHS.isInvalid() || RHS.isInvalid()) 6681 return QualType(); 6682 6683 // Enforce type constraints: C99 6.5.6p3. 6684 6685 // Handle the common case first (both operands are arithmetic). 6686 if (!compType.isNull() && compType->isArithmeticType()) { 6687 if (CompLHSTy) *CompLHSTy = compType; 6688 return compType; 6689 } 6690 6691 // Either ptr - int or ptr - ptr. 6692 if (LHS.get()->getType()->isAnyPointerType()) { 6693 QualType lpointee = LHS.get()->getType()->getPointeeType(); 6694 6695 // Diagnose bad cases where we step over interface counts. 6696 if (LHS.get()->getType()->isObjCObjectPointerType() && 6697 checkArithmeticOnObjCPointer(*this, Loc, LHS.get())) 6698 return QualType(); 6699 6700 // The result type of a pointer-int computation is the pointer type. 6701 if (RHS.get()->getType()->isIntegerType()) { 6702 if (!checkArithmeticOpPointerOperand(*this, Loc, LHS.get())) 6703 return QualType(); 6704 6705 // Check array bounds for pointer arithemtic 6706 CheckArrayAccess(LHS.get(), RHS.get(), /*ArraySubscriptExpr*/0, 6707 /*AllowOnePastEnd*/true, /*IndexNegated*/true); 6708 6709 if (CompLHSTy) *CompLHSTy = LHS.get()->getType(); 6710 return LHS.get()->getType(); 6711 } 6712 6713 // Handle pointer-pointer subtractions. 6714 if (const PointerType *RHSPTy 6715 = RHS.get()->getType()->getAs<PointerType>()) { 6716 QualType rpointee = RHSPTy->getPointeeType(); 6717 6718 if (getLangOpts().CPlusPlus) { 6719 // Pointee types must be the same: C++ [expr.add] 6720 if (!Context.hasSameUnqualifiedType(lpointee, rpointee)) { 6721 diagnosePointerIncompatibility(*this, Loc, LHS.get(), RHS.get()); 6722 } 6723 } else { 6724 // Pointee types must be compatible C99 6.5.6p3 6725 if (!Context.typesAreCompatible( 6726 Context.getCanonicalType(lpointee).getUnqualifiedType(), 6727 Context.getCanonicalType(rpointee).getUnqualifiedType())) { 6728 diagnosePointerIncompatibility(*this, Loc, LHS.get(), RHS.get()); 6729 return QualType(); 6730 } 6731 } 6732 6733 if (!checkArithmeticBinOpPointerOperands(*this, Loc, 6734 LHS.get(), RHS.get())) 6735 return QualType(); 6736 6737 if (CompLHSTy) *CompLHSTy = LHS.get()->getType(); 6738 return Context.getPointerDiffType(); 6739 } 6740 } 6741 6742 return InvalidOperands(Loc, LHS, RHS); 6743} 6744 6745static bool isScopedEnumerationType(QualType T) { 6746 if (const EnumType *ET = dyn_cast<EnumType>(T)) 6747 return ET->getDecl()->isScoped(); 6748 return false; 6749} 6750 6751static void DiagnoseBadShiftValues(Sema& S, ExprResult &LHS, ExprResult &RHS, 6752 SourceLocation Loc, unsigned Opc, 6753 QualType LHSType) { 6754 // OpenCL 6.3j: shift values are effectively % word size of LHS (more defined), 6755 // so skip remaining warnings as we don't want to modify values within Sema. 6756 if (S.getLangOpts().OpenCL) 6757 return; 6758 6759 llvm::APSInt Right; 6760 // Check right/shifter operand 6761 if (RHS.get()->isValueDependent() || 6762 !RHS.get()->isIntegerConstantExpr(Right, S.Context)) 6763 return; 6764 6765 if (Right.isNegative()) { 6766 S.DiagRuntimeBehavior(Loc, RHS.get(), 6767 S.PDiag(diag::warn_shift_negative) 6768 << RHS.get()->getSourceRange()); 6769 return; 6770 } 6771 llvm::APInt LeftBits(Right.getBitWidth(), 6772 S.Context.getTypeSize(LHS.get()->getType())); 6773 if (Right.uge(LeftBits)) { 6774 S.DiagRuntimeBehavior(Loc, RHS.get(), 6775 S.PDiag(diag::warn_shift_gt_typewidth) 6776 << RHS.get()->getSourceRange()); 6777 return; 6778 } 6779 if (Opc != BO_Shl) 6780 return; 6781 6782 // When left shifting an ICE which is signed, we can check for overflow which 6783 // according to C++ has undefined behavior ([expr.shift] 5.8/2). Unsigned 6784 // integers have defined behavior modulo one more than the maximum value 6785 // representable in the result type, so never warn for those. 6786 llvm::APSInt Left; 6787 if (LHS.get()->isValueDependent() || 6788 !LHS.get()->isIntegerConstantExpr(Left, S.Context) || 6789 LHSType->hasUnsignedIntegerRepresentation()) 6790 return; 6791 llvm::APInt ResultBits = 6792 static_cast<llvm::APInt&>(Right) + Left.getMinSignedBits(); 6793 if (LeftBits.uge(ResultBits)) 6794 return; 6795 llvm::APSInt Result = Left.extend(ResultBits.getLimitedValue()); 6796 Result = Result.shl(Right); 6797 6798 // Print the bit representation of the signed integer as an unsigned 6799 // hexadecimal number. 6800 SmallString<40> HexResult; 6801 Result.toString(HexResult, 16, /*Signed =*/false, /*Literal =*/true); 6802 6803 // If we are only missing a sign bit, this is less likely to result in actual 6804 // bugs -- if the result is cast back to an unsigned type, it will have the 6805 // expected value. Thus we place this behind a different warning that can be 6806 // turned off separately if needed. 6807 if (LeftBits == ResultBits - 1) { 6808 S.Diag(Loc, diag::warn_shift_result_sets_sign_bit) 6809 << HexResult.str() << LHSType 6810 << LHS.get()->getSourceRange() << RHS.get()->getSourceRange(); 6811 return; 6812 } 6813 6814 S.Diag(Loc, diag::warn_shift_result_gt_typewidth) 6815 << HexResult.str() << Result.getMinSignedBits() << LHSType 6816 << Left.getBitWidth() << LHS.get()->getSourceRange() 6817 << RHS.get()->getSourceRange(); 6818} 6819 6820// C99 6.5.7 6821QualType Sema::CheckShiftOperands(ExprResult &LHS, ExprResult &RHS, 6822 SourceLocation Loc, unsigned Opc, 6823 bool IsCompAssign) { 6824 checkArithmeticNull(*this, LHS, RHS, Loc, /*isCompare=*/false); 6825 6826 // C99 6.5.7p2: Each of the operands shall have integer type. 6827 if (!LHS.get()->getType()->hasIntegerRepresentation() || 6828 !RHS.get()->getType()->hasIntegerRepresentation()) 6829 return InvalidOperands(Loc, LHS, RHS); 6830 6831 // C++0x: Don't allow scoped enums. FIXME: Use something better than 6832 // hasIntegerRepresentation() above instead of this. 6833 if (isScopedEnumerationType(LHS.get()->getType()) || 6834 isScopedEnumerationType(RHS.get()->getType())) { 6835 return InvalidOperands(Loc, LHS, RHS); 6836 } 6837 6838 // Vector shifts promote their scalar inputs to vector type. 6839 if (LHS.get()->getType()->isVectorType() || 6840 RHS.get()->getType()->isVectorType()) 6841 return CheckVectorOperands(LHS, RHS, Loc, IsCompAssign); 6842 6843 // Shifts don't perform usual arithmetic conversions, they just do integer 6844 // promotions on each operand. C99 6.5.7p3 6845 6846 // For the LHS, do usual unary conversions, but then reset them away 6847 // if this is a compound assignment. 6848 ExprResult OldLHS = LHS; 6849 LHS = UsualUnaryConversions(LHS.take()); 6850 if (LHS.isInvalid()) 6851 return QualType(); 6852 QualType LHSType = LHS.get()->getType(); 6853 if (IsCompAssign) LHS = OldLHS; 6854 6855 // The RHS is simpler. 6856 RHS = UsualUnaryConversions(RHS.take()); 6857 if (RHS.isInvalid()) 6858 return QualType(); 6859 6860 // Sanity-check shift operands 6861 DiagnoseBadShiftValues(*this, LHS, RHS, Loc, Opc, LHSType); 6862 6863 // "The type of the result is that of the promoted left operand." 6864 return LHSType; 6865} 6866 6867static bool IsWithinTemplateSpecialization(Decl *D) { 6868 if (DeclContext *DC = D->getDeclContext()) { 6869 if (isa<ClassTemplateSpecializationDecl>(DC)) 6870 return true; 6871 if (FunctionDecl *FD = dyn_cast<FunctionDecl>(DC)) 6872 return FD->isFunctionTemplateSpecialization(); 6873 } 6874 return false; 6875} 6876 6877/// If two different enums are compared, raise a warning. 6878static void checkEnumComparison(Sema &S, SourceLocation Loc, Expr *LHS, 6879 Expr *RHS) { 6880 QualType LHSStrippedType = LHS->IgnoreParenImpCasts()->getType(); 6881 QualType RHSStrippedType = RHS->IgnoreParenImpCasts()->getType(); 6882 6883 const EnumType *LHSEnumType = LHSStrippedType->getAs<EnumType>(); 6884 if (!LHSEnumType) 6885 return; 6886 const EnumType *RHSEnumType = RHSStrippedType->getAs<EnumType>(); 6887 if (!RHSEnumType) 6888 return; 6889 6890 // Ignore anonymous enums. 6891 if (!LHSEnumType->getDecl()->getIdentifier()) 6892 return; 6893 if (!RHSEnumType->getDecl()->getIdentifier()) 6894 return; 6895 6896 if (S.Context.hasSameUnqualifiedType(LHSStrippedType, RHSStrippedType)) 6897 return; 6898 6899 S.Diag(Loc, diag::warn_comparison_of_mixed_enum_types) 6900 << LHSStrippedType << RHSStrippedType 6901 << LHS->getSourceRange() << RHS->getSourceRange(); 6902} 6903 6904/// \brief Diagnose bad pointer comparisons. 6905static void diagnoseDistinctPointerComparison(Sema &S, SourceLocation Loc, 6906 ExprResult &LHS, ExprResult &RHS, 6907 bool IsError) { 6908 S.Diag(Loc, IsError ? diag::err_typecheck_comparison_of_distinct_pointers 6909 : diag::ext_typecheck_comparison_of_distinct_pointers) 6910 << LHS.get()->getType() << RHS.get()->getType() 6911 << LHS.get()->getSourceRange() << RHS.get()->getSourceRange(); 6912} 6913 6914/// \brief Returns false if the pointers are converted to a composite type, 6915/// true otherwise. 6916static bool convertPointersToCompositeType(Sema &S, SourceLocation Loc, 6917 ExprResult &LHS, ExprResult &RHS) { 6918 // C++ [expr.rel]p2: 6919 // [...] Pointer conversions (4.10) and qualification 6920 // conversions (4.4) are performed on pointer operands (or on 6921 // a pointer operand and a null pointer constant) to bring 6922 // them to their composite pointer type. [...] 6923 // 6924 // C++ [expr.eq]p1 uses the same notion for (in)equality 6925 // comparisons of pointers. 6926 6927 // C++ [expr.eq]p2: 6928 // In addition, pointers to members can be compared, or a pointer to 6929 // member and a null pointer constant. Pointer to member conversions 6930 // (4.11) and qualification conversions (4.4) are performed to bring 6931 // them to a common type. If one operand is a null pointer constant, 6932 // the common type is the type of the other operand. Otherwise, the 6933 // common type is a pointer to member type similar (4.4) to the type 6934 // of one of the operands, with a cv-qualification signature (4.4) 6935 // that is the union of the cv-qualification signatures of the operand 6936 // types. 6937 6938 QualType LHSType = LHS.get()->getType(); 6939 QualType RHSType = RHS.get()->getType(); 6940 assert((LHSType->isPointerType() && RHSType->isPointerType()) || 6941 (LHSType->isMemberPointerType() && RHSType->isMemberPointerType())); 6942 6943 bool NonStandardCompositeType = false; 6944 bool *BoolPtr = S.isSFINAEContext() ? 0 : &NonStandardCompositeType; 6945 QualType T = S.FindCompositePointerType(Loc, LHS, RHS, BoolPtr); 6946 if (T.isNull()) { 6947 diagnoseDistinctPointerComparison(S, Loc, LHS, RHS, /*isError*/true); 6948 return true; 6949 } 6950 6951 if (NonStandardCompositeType) 6952 S.Diag(Loc, diag::ext_typecheck_comparison_of_distinct_pointers_nonstandard) 6953 << LHSType << RHSType << T << LHS.get()->getSourceRange() 6954 << RHS.get()->getSourceRange(); 6955 6956 LHS = S.ImpCastExprToType(LHS.take(), T, CK_BitCast); 6957 RHS = S.ImpCastExprToType(RHS.take(), T, CK_BitCast); 6958 return false; 6959} 6960 6961static void diagnoseFunctionPointerToVoidComparison(Sema &S, SourceLocation Loc, 6962 ExprResult &LHS, 6963 ExprResult &RHS, 6964 bool IsError) { 6965 S.Diag(Loc, IsError ? diag::err_typecheck_comparison_of_fptr_to_void 6966 : diag::ext_typecheck_comparison_of_fptr_to_void) 6967 << LHS.get()->getType() << RHS.get()->getType() 6968 << LHS.get()->getSourceRange() << RHS.get()->getSourceRange(); 6969} 6970 6971static bool isObjCObjectLiteral(ExprResult &E) { 6972 switch (E.get()->IgnoreParenImpCasts()->getStmtClass()) { 6973 case Stmt::ObjCArrayLiteralClass: 6974 case Stmt::ObjCDictionaryLiteralClass: 6975 case Stmt::ObjCStringLiteralClass: 6976 case Stmt::ObjCBoxedExprClass: 6977 return true; 6978 default: 6979 // Note that ObjCBoolLiteral is NOT an object literal! 6980 return false; 6981 } 6982} 6983 6984static bool hasIsEqualMethod(Sema &S, const Expr *LHS, const Expr *RHS) { 6985 const ObjCObjectPointerType *Type = 6986 LHS->getType()->getAs<ObjCObjectPointerType>(); 6987 6988 // If this is not actually an Objective-C object, bail out. 6989 if (!Type) 6990 return false; 6991 6992 // Get the LHS object's interface type. 6993 QualType InterfaceType = Type->getPointeeType(); 6994 if (const ObjCObjectType *iQFaceTy = 6995 InterfaceType->getAsObjCQualifiedInterfaceType()) 6996 InterfaceType = iQFaceTy->getBaseType(); 6997 6998 // If the RHS isn't an Objective-C object, bail out. 6999 if (!RHS->getType()->isObjCObjectPointerType()) 7000 return false; 7001 7002 // Try to find the -isEqual: method. 7003 Selector IsEqualSel = S.NSAPIObj->getIsEqualSelector(); 7004 ObjCMethodDecl *Method = S.LookupMethodInObjectType(IsEqualSel, 7005 InterfaceType, 7006 /*instance=*/true); 7007 if (!Method) { 7008 if (Type->isObjCIdType()) { 7009 // For 'id', just check the global pool. 7010 Method = S.LookupInstanceMethodInGlobalPool(IsEqualSel, SourceRange(), 7011 /*receiverId=*/true, 7012 /*warn=*/false); 7013 } else { 7014 // Check protocols. 7015 Method = S.LookupMethodInQualifiedType(IsEqualSel, Type, 7016 /*instance=*/true); 7017 } 7018 } 7019 7020 if (!Method) 7021 return false; 7022 7023 QualType T = Method->param_begin()[0]->getType(); 7024 if (!T->isObjCObjectPointerType()) 7025 return false; 7026 7027 QualType R = Method->getResultType(); 7028 if (!R->isScalarType()) 7029 return false; 7030 7031 return true; 7032} 7033 7034Sema::ObjCLiteralKind Sema::CheckLiteralKind(Expr *FromE) { 7035 FromE = FromE->IgnoreParenImpCasts(); 7036 switch (FromE->getStmtClass()) { 7037 default: 7038 break; 7039 case Stmt::ObjCStringLiteralClass: 7040 // "string literal" 7041 return LK_String; 7042 case Stmt::ObjCArrayLiteralClass: 7043 // "array literal" 7044 return LK_Array; 7045 case Stmt::ObjCDictionaryLiteralClass: 7046 // "dictionary literal" 7047 return LK_Dictionary; 7048 case Stmt::BlockExprClass: 7049 return LK_Block; 7050 case Stmt::ObjCBoxedExprClass: { 7051 Expr *Inner = cast<ObjCBoxedExpr>(FromE)->getSubExpr()->IgnoreParens(); 7052 switch (Inner->getStmtClass()) { 7053 case Stmt::IntegerLiteralClass: 7054 case Stmt::FloatingLiteralClass: 7055 case Stmt::CharacterLiteralClass: 7056 case Stmt::ObjCBoolLiteralExprClass: 7057 case Stmt::CXXBoolLiteralExprClass: 7058 // "numeric literal" 7059 return LK_Numeric; 7060 case Stmt::ImplicitCastExprClass: { 7061 CastKind CK = cast<CastExpr>(Inner)->getCastKind(); 7062 // Boolean literals can be represented by implicit casts. 7063 if (CK == CK_IntegralToBoolean || CK == CK_IntegralCast) 7064 return LK_Numeric; 7065 break; 7066 } 7067 default: 7068 break; 7069 } 7070 return LK_Boxed; 7071 } 7072 } 7073 return LK_None; 7074} 7075 7076static void diagnoseObjCLiteralComparison(Sema &S, SourceLocation Loc, 7077 ExprResult &LHS, ExprResult &RHS, 7078 BinaryOperator::Opcode Opc){ 7079 Expr *Literal; 7080 Expr *Other; 7081 if (isObjCObjectLiteral(LHS)) { 7082 Literal = LHS.get(); 7083 Other = RHS.get(); 7084 } else { 7085 Literal = RHS.get(); 7086 Other = LHS.get(); 7087 } 7088 7089 // Don't warn on comparisons against nil. 7090 Other = Other->IgnoreParenCasts(); 7091 if (Other->isNullPointerConstant(S.getASTContext(), 7092 Expr::NPC_ValueDependentIsNotNull)) 7093 return; 7094 7095 // This should be kept in sync with warn_objc_literal_comparison. 7096 // LK_String should always be after the other literals, since it has its own 7097 // warning flag. 7098 Sema::ObjCLiteralKind LiteralKind = S.CheckLiteralKind(Literal); 7099 assert(LiteralKind != Sema::LK_Block); 7100 if (LiteralKind == Sema::LK_None) { 7101 llvm_unreachable("Unknown Objective-C object literal kind"); 7102 } 7103 7104 if (LiteralKind == Sema::LK_String) 7105 S.Diag(Loc, diag::warn_objc_string_literal_comparison) 7106 << Literal->getSourceRange(); 7107 else 7108 S.Diag(Loc, diag::warn_objc_literal_comparison) 7109 << LiteralKind << Literal->getSourceRange(); 7110 7111 if (BinaryOperator::isEqualityOp(Opc) && 7112 hasIsEqualMethod(S, LHS.get(), RHS.get())) { 7113 SourceLocation Start = LHS.get()->getLocStart(); 7114 SourceLocation End = S.PP.getLocForEndOfToken(RHS.get()->getLocEnd()); 7115 CharSourceRange OpRange = 7116 CharSourceRange::getCharRange(Loc, S.PP.getLocForEndOfToken(Loc)); 7117 7118 S.Diag(Loc, diag::note_objc_literal_comparison_isequal) 7119 << FixItHint::CreateInsertion(Start, Opc == BO_EQ ? "[" : "![") 7120 << FixItHint::CreateReplacement(OpRange, " isEqual:") 7121 << FixItHint::CreateInsertion(End, "]"); 7122 } 7123} 7124 7125// C99 6.5.8, C++ [expr.rel] 7126QualType Sema::CheckCompareOperands(ExprResult &LHS, ExprResult &RHS, 7127 SourceLocation Loc, unsigned OpaqueOpc, 7128 bool IsRelational) { 7129 checkArithmeticNull(*this, LHS, RHS, Loc, /*isCompare=*/true); 7130 7131 BinaryOperatorKind Opc = (BinaryOperatorKind) OpaqueOpc; 7132 7133 // Handle vector comparisons separately. 7134 if (LHS.get()->getType()->isVectorType() || 7135 RHS.get()->getType()->isVectorType()) 7136 return CheckVectorCompareOperands(LHS, RHS, Loc, IsRelational); 7137 7138 QualType LHSType = LHS.get()->getType(); 7139 QualType RHSType = RHS.get()->getType(); 7140 7141 Expr *LHSStripped = LHS.get()->IgnoreParenImpCasts(); 7142 Expr *RHSStripped = RHS.get()->IgnoreParenImpCasts(); 7143 7144 checkEnumComparison(*this, Loc, LHS.get(), RHS.get()); 7145 7146 if (!LHSType->hasFloatingRepresentation() && 7147 !(LHSType->isBlockPointerType() && IsRelational) && 7148 !LHS.get()->getLocStart().isMacroID() && 7149 !RHS.get()->getLocStart().isMacroID()) { 7150 // For non-floating point types, check for self-comparisons of the form 7151 // x == x, x != x, x < x, etc. These always evaluate to a constant, and 7152 // often indicate logic errors in the program. 7153 // 7154 // NOTE: Don't warn about comparison expressions resulting from macro 7155 // expansion. Also don't warn about comparisons which are only self 7156 // comparisons within a template specialization. The warnings should catch 7157 // obvious cases in the definition of the template anyways. The idea is to 7158 // warn when the typed comparison operator will always evaluate to the same 7159 // result. 7160 if (DeclRefExpr* DRL = dyn_cast<DeclRefExpr>(LHSStripped)) { 7161 if (DeclRefExpr* DRR = dyn_cast<DeclRefExpr>(RHSStripped)) { 7162 if (DRL->getDecl() == DRR->getDecl() && 7163 !IsWithinTemplateSpecialization(DRL->getDecl())) { 7164 DiagRuntimeBehavior(Loc, 0, PDiag(diag::warn_comparison_always) 7165 << 0 // self- 7166 << (Opc == BO_EQ 7167 || Opc == BO_LE 7168 || Opc == BO_GE)); 7169 } else if (LHSType->isArrayType() && RHSType->isArrayType() && 7170 !DRL->getDecl()->getType()->isReferenceType() && 7171 !DRR->getDecl()->getType()->isReferenceType()) { 7172 // what is it always going to eval to? 7173 char always_evals_to; 7174 switch(Opc) { 7175 case BO_EQ: // e.g. array1 == array2 7176 always_evals_to = 0; // false 7177 break; 7178 case BO_NE: // e.g. array1 != array2 7179 always_evals_to = 1; // true 7180 break; 7181 default: 7182 // best we can say is 'a constant' 7183 always_evals_to = 2; // e.g. array1 <= array2 7184 break; 7185 } 7186 DiagRuntimeBehavior(Loc, 0, PDiag(diag::warn_comparison_always) 7187 << 1 // array 7188 << always_evals_to); 7189 } 7190 } 7191 } 7192 7193 if (isa<CastExpr>(LHSStripped)) 7194 LHSStripped = LHSStripped->IgnoreParenCasts(); 7195 if (isa<CastExpr>(RHSStripped)) 7196 RHSStripped = RHSStripped->IgnoreParenCasts(); 7197 7198 // Warn about comparisons against a string constant (unless the other 7199 // operand is null), the user probably wants strcmp. 7200 Expr *literalString = 0; 7201 Expr *literalStringStripped = 0; 7202 if ((isa<StringLiteral>(LHSStripped) || isa<ObjCEncodeExpr>(LHSStripped)) && 7203 !RHSStripped->isNullPointerConstant(Context, 7204 Expr::NPC_ValueDependentIsNull)) { 7205 literalString = LHS.get(); 7206 literalStringStripped = LHSStripped; 7207 } else if ((isa<StringLiteral>(RHSStripped) || 7208 isa<ObjCEncodeExpr>(RHSStripped)) && 7209 !LHSStripped->isNullPointerConstant(Context, 7210 Expr::NPC_ValueDependentIsNull)) { 7211 literalString = RHS.get(); 7212 literalStringStripped = RHSStripped; 7213 } 7214 7215 if (literalString) { 7216 std::string resultComparison; 7217 switch (Opc) { 7218 case BO_LT: resultComparison = ") < 0"; break; 7219 case BO_GT: resultComparison = ") > 0"; break; 7220 case BO_LE: resultComparison = ") <= 0"; break; 7221 case BO_GE: resultComparison = ") >= 0"; break; 7222 case BO_EQ: resultComparison = ") == 0"; break; 7223 case BO_NE: resultComparison = ") != 0"; break; 7224 default: llvm_unreachable("Invalid comparison operator"); 7225 } 7226 7227 DiagRuntimeBehavior(Loc, 0, 7228 PDiag(diag::warn_stringcompare) 7229 << isa<ObjCEncodeExpr>(literalStringStripped) 7230 << literalString->getSourceRange()); 7231 } 7232 } 7233 7234 // C99 6.5.8p3 / C99 6.5.9p4 7235 if (LHS.get()->getType()->isArithmeticType() && 7236 RHS.get()->getType()->isArithmeticType()) { 7237 UsualArithmeticConversions(LHS, RHS); 7238 if (LHS.isInvalid() || RHS.isInvalid()) 7239 return QualType(); 7240 } 7241 else { 7242 LHS = UsualUnaryConversions(LHS.take()); 7243 if (LHS.isInvalid()) 7244 return QualType(); 7245 7246 RHS = UsualUnaryConversions(RHS.take()); 7247 if (RHS.isInvalid()) 7248 return QualType(); 7249 } 7250 7251 LHSType = LHS.get()->getType(); 7252 RHSType = RHS.get()->getType(); 7253 7254 // The result of comparisons is 'bool' in C++, 'int' in C. 7255 QualType ResultTy = Context.getLogicalOperationType(); 7256 7257 if (IsRelational) { 7258 if (LHSType->isRealType() && RHSType->isRealType()) 7259 return ResultTy; 7260 } else { 7261 // Check for comparisons of floating point operands using != and ==. 7262 if (LHSType->hasFloatingRepresentation()) 7263 CheckFloatComparison(Loc, LHS.get(), RHS.get()); 7264 7265 if (LHSType->isArithmeticType() && RHSType->isArithmeticType()) 7266 return ResultTy; 7267 } 7268 7269 bool LHSIsNull = LHS.get()->isNullPointerConstant(Context, 7270 Expr::NPC_ValueDependentIsNull); 7271 bool RHSIsNull = RHS.get()->isNullPointerConstant(Context, 7272 Expr::NPC_ValueDependentIsNull); 7273 7274 // All of the following pointer-related warnings are GCC extensions, except 7275 // when handling null pointer constants. 7276 if (LHSType->isPointerType() && RHSType->isPointerType()) { // C99 6.5.8p2 7277 QualType LCanPointeeTy = 7278 LHSType->castAs<PointerType>()->getPointeeType().getCanonicalType(); 7279 QualType RCanPointeeTy = 7280 RHSType->castAs<PointerType>()->getPointeeType().getCanonicalType(); 7281 7282 if (getLangOpts().CPlusPlus) { 7283 if (LCanPointeeTy == RCanPointeeTy) 7284 return ResultTy; 7285 if (!IsRelational && 7286 (LCanPointeeTy->isVoidType() || RCanPointeeTy->isVoidType())) { 7287 // Valid unless comparison between non-null pointer and function pointer 7288 // This is a gcc extension compatibility comparison. 7289 // In a SFINAE context, we treat this as a hard error to maintain 7290 // conformance with the C++ standard. 7291 if ((LCanPointeeTy->isFunctionType() || RCanPointeeTy->isFunctionType()) 7292 && !LHSIsNull && !RHSIsNull) { 7293 diagnoseFunctionPointerToVoidComparison( 7294 *this, Loc, LHS, RHS, /*isError*/ (bool)isSFINAEContext()); 7295 7296 if (isSFINAEContext()) 7297 return QualType(); 7298 7299 RHS = ImpCastExprToType(RHS.take(), LHSType, CK_BitCast); 7300 return ResultTy; 7301 } 7302 } 7303 7304 if (convertPointersToCompositeType(*this, Loc, LHS, RHS)) 7305 return QualType(); 7306 else 7307 return ResultTy; 7308 } 7309 // C99 6.5.9p2 and C99 6.5.8p2 7310 if (Context.typesAreCompatible(LCanPointeeTy.getUnqualifiedType(), 7311 RCanPointeeTy.getUnqualifiedType())) { 7312 // Valid unless a relational comparison of function pointers 7313 if (IsRelational && LCanPointeeTy->isFunctionType()) { 7314 Diag(Loc, diag::ext_typecheck_ordered_comparison_of_function_pointers) 7315 << LHSType << RHSType << LHS.get()->getSourceRange() 7316 << RHS.get()->getSourceRange(); 7317 } 7318 } else if (!IsRelational && 7319 (LCanPointeeTy->isVoidType() || RCanPointeeTy->isVoidType())) { 7320 // Valid unless comparison between non-null pointer and function pointer 7321 if ((LCanPointeeTy->isFunctionType() || RCanPointeeTy->isFunctionType()) 7322 && !LHSIsNull && !RHSIsNull) 7323 diagnoseFunctionPointerToVoidComparison(*this, Loc, LHS, RHS, 7324 /*isError*/false); 7325 } else { 7326 // Invalid 7327 diagnoseDistinctPointerComparison(*this, Loc, LHS, RHS, /*isError*/false); 7328 } 7329 if (LCanPointeeTy != RCanPointeeTy) { 7330 if (LHSIsNull && !RHSIsNull) 7331 LHS = ImpCastExprToType(LHS.take(), RHSType, CK_BitCast); 7332 else 7333 RHS = ImpCastExprToType(RHS.take(), LHSType, CK_BitCast); 7334 } 7335 return ResultTy; 7336 } 7337 7338 if (getLangOpts().CPlusPlus) { 7339 // Comparison of nullptr_t with itself. 7340 if (LHSType->isNullPtrType() && RHSType->isNullPtrType()) 7341 return ResultTy; 7342 7343 // Comparison of pointers with null pointer constants and equality 7344 // comparisons of member pointers to null pointer constants. 7345 if (RHSIsNull && 7346 ((LHSType->isAnyPointerType() || LHSType->isNullPtrType()) || 7347 (!IsRelational && 7348 (LHSType->isMemberPointerType() || LHSType->isBlockPointerType())))) { 7349 RHS = ImpCastExprToType(RHS.take(), LHSType, 7350 LHSType->isMemberPointerType() 7351 ? CK_NullToMemberPointer 7352 : CK_NullToPointer); 7353 return ResultTy; 7354 } 7355 if (LHSIsNull && 7356 ((RHSType->isAnyPointerType() || RHSType->isNullPtrType()) || 7357 (!IsRelational && 7358 (RHSType->isMemberPointerType() || RHSType->isBlockPointerType())))) { 7359 LHS = ImpCastExprToType(LHS.take(), RHSType, 7360 RHSType->isMemberPointerType() 7361 ? CK_NullToMemberPointer 7362 : CK_NullToPointer); 7363 return ResultTy; 7364 } 7365 7366 // Comparison of member pointers. 7367 if (!IsRelational && 7368 LHSType->isMemberPointerType() && RHSType->isMemberPointerType()) { 7369 if (convertPointersToCompositeType(*this, Loc, LHS, RHS)) 7370 return QualType(); 7371 else 7372 return ResultTy; 7373 } 7374 7375 // Handle scoped enumeration types specifically, since they don't promote 7376 // to integers. 7377 if (LHS.get()->getType()->isEnumeralType() && 7378 Context.hasSameUnqualifiedType(LHS.get()->getType(), 7379 RHS.get()->getType())) 7380 return ResultTy; 7381 } 7382 7383 // Handle block pointer types. 7384 if (!IsRelational && LHSType->isBlockPointerType() && 7385 RHSType->isBlockPointerType()) { 7386 QualType lpointee = LHSType->castAs<BlockPointerType>()->getPointeeType(); 7387 QualType rpointee = RHSType->castAs<BlockPointerType>()->getPointeeType(); 7388 7389 if (!LHSIsNull && !RHSIsNull && 7390 !Context.typesAreCompatible(lpointee, rpointee)) { 7391 Diag(Loc, diag::err_typecheck_comparison_of_distinct_blocks) 7392 << LHSType << RHSType << LHS.get()->getSourceRange() 7393 << RHS.get()->getSourceRange(); 7394 } 7395 RHS = ImpCastExprToType(RHS.take(), LHSType, CK_BitCast); 7396 return ResultTy; 7397 } 7398 7399 // Allow block pointers to be compared with null pointer constants. 7400 if (!IsRelational 7401 && ((LHSType->isBlockPointerType() && RHSType->isPointerType()) 7402 || (LHSType->isPointerType() && RHSType->isBlockPointerType()))) { 7403 if (!LHSIsNull && !RHSIsNull) { 7404 if (!((RHSType->isPointerType() && RHSType->castAs<PointerType>() 7405 ->getPointeeType()->isVoidType()) 7406 || (LHSType->isPointerType() && LHSType->castAs<PointerType>() 7407 ->getPointeeType()->isVoidType()))) 7408 Diag(Loc, diag::err_typecheck_comparison_of_distinct_blocks) 7409 << LHSType << RHSType << LHS.get()->getSourceRange() 7410 << RHS.get()->getSourceRange(); 7411 } 7412 if (LHSIsNull && !RHSIsNull) 7413 LHS = ImpCastExprToType(LHS.take(), RHSType, 7414 RHSType->isPointerType() ? CK_BitCast 7415 : CK_AnyPointerToBlockPointerCast); 7416 else 7417 RHS = ImpCastExprToType(RHS.take(), LHSType, 7418 LHSType->isPointerType() ? CK_BitCast 7419 : CK_AnyPointerToBlockPointerCast); 7420 return ResultTy; 7421 } 7422 7423 if (LHSType->isObjCObjectPointerType() || 7424 RHSType->isObjCObjectPointerType()) { 7425 const PointerType *LPT = LHSType->getAs<PointerType>(); 7426 const PointerType *RPT = RHSType->getAs<PointerType>(); 7427 if (LPT || RPT) { 7428 bool LPtrToVoid = LPT ? LPT->getPointeeType()->isVoidType() : false; 7429 bool RPtrToVoid = RPT ? RPT->getPointeeType()->isVoidType() : false; 7430 7431 if (!LPtrToVoid && !RPtrToVoid && 7432 !Context.typesAreCompatible(LHSType, RHSType)) { 7433 diagnoseDistinctPointerComparison(*this, Loc, LHS, RHS, 7434 /*isError*/false); 7435 } 7436 if (LHSIsNull && !RHSIsNull) 7437 LHS = ImpCastExprToType(LHS.take(), RHSType, 7438 RPT ? CK_BitCast :CK_CPointerToObjCPointerCast); 7439 else 7440 RHS = ImpCastExprToType(RHS.take(), LHSType, 7441 LPT ? CK_BitCast :CK_CPointerToObjCPointerCast); 7442 return ResultTy; 7443 } 7444 if (LHSType->isObjCObjectPointerType() && 7445 RHSType->isObjCObjectPointerType()) { 7446 if (!Context.areComparableObjCPointerTypes(LHSType, RHSType)) 7447 diagnoseDistinctPointerComparison(*this, Loc, LHS, RHS, 7448 /*isError*/false); 7449 if (isObjCObjectLiteral(LHS) || isObjCObjectLiteral(RHS)) 7450 diagnoseObjCLiteralComparison(*this, Loc, LHS, RHS, Opc); 7451 7452 if (LHSIsNull && !RHSIsNull) 7453 LHS = ImpCastExprToType(LHS.take(), RHSType, CK_BitCast); 7454 else 7455 RHS = ImpCastExprToType(RHS.take(), LHSType, CK_BitCast); 7456 return ResultTy; 7457 } 7458 } 7459 if ((LHSType->isAnyPointerType() && RHSType->isIntegerType()) || 7460 (LHSType->isIntegerType() && RHSType->isAnyPointerType())) { 7461 unsigned DiagID = 0; 7462 bool isError = false; 7463 if (LangOpts.DebuggerSupport) { 7464 // Under a debugger, allow the comparison of pointers to integers, 7465 // since users tend to want to compare addresses. 7466 } else if ((LHSIsNull && LHSType->isIntegerType()) || 7467 (RHSIsNull && RHSType->isIntegerType())) { 7468 if (IsRelational && !getLangOpts().CPlusPlus) 7469 DiagID = diag::ext_typecheck_ordered_comparison_of_pointer_and_zero; 7470 } else if (IsRelational && !getLangOpts().CPlusPlus) 7471 DiagID = diag::ext_typecheck_ordered_comparison_of_pointer_integer; 7472 else if (getLangOpts().CPlusPlus) { 7473 DiagID = diag::err_typecheck_comparison_of_pointer_integer; 7474 isError = true; 7475 } else 7476 DiagID = diag::ext_typecheck_comparison_of_pointer_integer; 7477 7478 if (DiagID) { 7479 Diag(Loc, DiagID) 7480 << LHSType << RHSType << LHS.get()->getSourceRange() 7481 << RHS.get()->getSourceRange(); 7482 if (isError) 7483 return QualType(); 7484 } 7485 7486 if (LHSType->isIntegerType()) 7487 LHS = ImpCastExprToType(LHS.take(), RHSType, 7488 LHSIsNull ? CK_NullToPointer : CK_IntegralToPointer); 7489 else 7490 RHS = ImpCastExprToType(RHS.take(), LHSType, 7491 RHSIsNull ? CK_NullToPointer : CK_IntegralToPointer); 7492 return ResultTy; 7493 } 7494 7495 // Handle block pointers. 7496 if (!IsRelational && RHSIsNull 7497 && LHSType->isBlockPointerType() && RHSType->isIntegerType()) { 7498 RHS = ImpCastExprToType(RHS.take(), LHSType, CK_NullToPointer); 7499 return ResultTy; 7500 } 7501 if (!IsRelational && LHSIsNull 7502 && LHSType->isIntegerType() && RHSType->isBlockPointerType()) { 7503 LHS = ImpCastExprToType(LHS.take(), RHSType, CK_NullToPointer); 7504 return ResultTy; 7505 } 7506 7507 return InvalidOperands(Loc, LHS, RHS); 7508} 7509 7510 7511// Return a signed type that is of identical size and number of elements. 7512// For floating point vectors, return an integer type of identical size 7513// and number of elements. 7514QualType Sema::GetSignedVectorType(QualType V) { 7515 const VectorType *VTy = V->getAs<VectorType>(); 7516 unsigned TypeSize = Context.getTypeSize(VTy->getElementType()); 7517 if (TypeSize == Context.getTypeSize(Context.CharTy)) 7518 return Context.getExtVectorType(Context.CharTy, VTy->getNumElements()); 7519 else if (TypeSize == Context.getTypeSize(Context.ShortTy)) 7520 return Context.getExtVectorType(Context.ShortTy, VTy->getNumElements()); 7521 else if (TypeSize == Context.getTypeSize(Context.IntTy)) 7522 return Context.getExtVectorType(Context.IntTy, VTy->getNumElements()); 7523 else if (TypeSize == Context.getTypeSize(Context.LongTy)) 7524 return Context.getExtVectorType(Context.LongTy, VTy->getNumElements()); 7525 assert(TypeSize == Context.getTypeSize(Context.LongLongTy) && 7526 "Unhandled vector element size in vector compare"); 7527 return Context.getExtVectorType(Context.LongLongTy, VTy->getNumElements()); 7528} 7529 7530/// CheckVectorCompareOperands - vector comparisons are a clang extension that 7531/// operates on extended vector types. Instead of producing an IntTy result, 7532/// like a scalar comparison, a vector comparison produces a vector of integer 7533/// types. 7534QualType Sema::CheckVectorCompareOperands(ExprResult &LHS, ExprResult &RHS, 7535 SourceLocation Loc, 7536 bool IsRelational) { 7537 // Check to make sure we're operating on vectors of the same type and width, 7538 // Allowing one side to be a scalar of element type. 7539 QualType vType = CheckVectorOperands(LHS, RHS, Loc, /*isCompAssign*/false); 7540 if (vType.isNull()) 7541 return vType; 7542 7543 QualType LHSType = LHS.get()->getType(); 7544 7545 // If AltiVec, the comparison results in a numeric type, i.e. 7546 // bool for C++, int for C 7547 if (vType->getAs<VectorType>()->getVectorKind() == VectorType::AltiVecVector) 7548 return Context.getLogicalOperationType(); 7549 7550 // For non-floating point types, check for self-comparisons of the form 7551 // x == x, x != x, x < x, etc. These always evaluate to a constant, and 7552 // often indicate logic errors in the program. 7553 if (!LHSType->hasFloatingRepresentation()) { 7554 if (DeclRefExpr* DRL 7555 = dyn_cast<DeclRefExpr>(LHS.get()->IgnoreParenImpCasts())) 7556 if (DeclRefExpr* DRR 7557 = dyn_cast<DeclRefExpr>(RHS.get()->IgnoreParenImpCasts())) 7558 if (DRL->getDecl() == DRR->getDecl()) 7559 DiagRuntimeBehavior(Loc, 0, 7560 PDiag(diag::warn_comparison_always) 7561 << 0 // self- 7562 << 2 // "a constant" 7563 ); 7564 } 7565 7566 // Check for comparisons of floating point operands using != and ==. 7567 if (!IsRelational && LHSType->hasFloatingRepresentation()) { 7568 assert (RHS.get()->getType()->hasFloatingRepresentation()); 7569 CheckFloatComparison(Loc, LHS.get(), RHS.get()); 7570 } 7571 7572 // Return a signed type for the vector. 7573 return GetSignedVectorType(LHSType); 7574} 7575 7576QualType Sema::CheckVectorLogicalOperands(ExprResult &LHS, ExprResult &RHS, 7577 SourceLocation Loc) { 7578 // Ensure that either both operands are of the same vector type, or 7579 // one operand is of a vector type and the other is of its element type. 7580 QualType vType = CheckVectorOperands(LHS, RHS, Loc, false); 7581 if (vType.isNull()) 7582 return InvalidOperands(Loc, LHS, RHS); 7583 if (getLangOpts().OpenCL && getLangOpts().OpenCLVersion < 120 && 7584 vType->hasFloatingRepresentation()) 7585 return InvalidOperands(Loc, LHS, RHS); 7586 7587 return GetSignedVectorType(LHS.get()->getType()); 7588} 7589 7590inline QualType Sema::CheckBitwiseOperands( 7591 ExprResult &LHS, ExprResult &RHS, SourceLocation Loc, bool IsCompAssign) { 7592 checkArithmeticNull(*this, LHS, RHS, Loc, /*isCompare=*/false); 7593 7594 if (LHS.get()->getType()->isVectorType() || 7595 RHS.get()->getType()->isVectorType()) { 7596 if (LHS.get()->getType()->hasIntegerRepresentation() && 7597 RHS.get()->getType()->hasIntegerRepresentation()) 7598 return CheckVectorOperands(LHS, RHS, Loc, IsCompAssign); 7599 7600 return InvalidOperands(Loc, LHS, RHS); 7601 } 7602 7603 ExprResult LHSResult = Owned(LHS), RHSResult = Owned(RHS); 7604 QualType compType = UsualArithmeticConversions(LHSResult, RHSResult, 7605 IsCompAssign); 7606 if (LHSResult.isInvalid() || RHSResult.isInvalid()) 7607 return QualType(); 7608 LHS = LHSResult.take(); 7609 RHS = RHSResult.take(); 7610 7611 if (!compType.isNull() && compType->isIntegralOrUnscopedEnumerationType()) 7612 return compType; 7613 return InvalidOperands(Loc, LHS, RHS); 7614} 7615 7616inline QualType Sema::CheckLogicalOperands( // C99 6.5.[13,14] 7617 ExprResult &LHS, ExprResult &RHS, SourceLocation Loc, unsigned Opc) { 7618 7619 // Check vector operands differently. 7620 if (LHS.get()->getType()->isVectorType() || RHS.get()->getType()->isVectorType()) 7621 return CheckVectorLogicalOperands(LHS, RHS, Loc); 7622 7623 // Diagnose cases where the user write a logical and/or but probably meant a 7624 // bitwise one. We do this when the LHS is a non-bool integer and the RHS 7625 // is a constant. 7626 if (LHS.get()->getType()->isIntegerType() && 7627 !LHS.get()->getType()->isBooleanType() && 7628 RHS.get()->getType()->isIntegerType() && !RHS.get()->isValueDependent() && 7629 // Don't warn in macros or template instantiations. 7630 !Loc.isMacroID() && ActiveTemplateInstantiations.empty()) { 7631 // If the RHS can be constant folded, and if it constant folds to something 7632 // that isn't 0 or 1 (which indicate a potential logical operation that 7633 // happened to fold to true/false) then warn. 7634 // Parens on the RHS are ignored. 7635 llvm::APSInt Result; 7636 if (RHS.get()->EvaluateAsInt(Result, Context)) 7637 if ((getLangOpts().Bool && !RHS.get()->getType()->isBooleanType()) || 7638 (Result != 0 && Result != 1)) { 7639 Diag(Loc, diag::warn_logical_instead_of_bitwise) 7640 << RHS.get()->getSourceRange() 7641 << (Opc == BO_LAnd ? "&&" : "||"); 7642 // Suggest replacing the logical operator with the bitwise version 7643 Diag(Loc, diag::note_logical_instead_of_bitwise_change_operator) 7644 << (Opc == BO_LAnd ? "&" : "|") 7645 << FixItHint::CreateReplacement(SourceRange( 7646 Loc, Lexer::getLocForEndOfToken(Loc, 0, getSourceManager(), 7647 getLangOpts())), 7648 Opc == BO_LAnd ? "&" : "|"); 7649 if (Opc == BO_LAnd) 7650 // Suggest replacing "Foo() && kNonZero" with "Foo()" 7651 Diag(Loc, diag::note_logical_instead_of_bitwise_remove_constant) 7652 << FixItHint::CreateRemoval( 7653 SourceRange( 7654 Lexer::getLocForEndOfToken(LHS.get()->getLocEnd(), 7655 0, getSourceManager(), 7656 getLangOpts()), 7657 RHS.get()->getLocEnd())); 7658 } 7659 } 7660 7661 if (!Context.getLangOpts().CPlusPlus) { 7662 // OpenCL v1.1 s6.3.g: The logical operators and (&&), or (||) do 7663 // not operate on the built-in scalar and vector float types. 7664 if (Context.getLangOpts().OpenCL && 7665 Context.getLangOpts().OpenCLVersion < 120) { 7666 if (LHS.get()->getType()->isFloatingType() || 7667 RHS.get()->getType()->isFloatingType()) 7668 return InvalidOperands(Loc, LHS, RHS); 7669 } 7670 7671 LHS = UsualUnaryConversions(LHS.take()); 7672 if (LHS.isInvalid()) 7673 return QualType(); 7674 7675 RHS = UsualUnaryConversions(RHS.take()); 7676 if (RHS.isInvalid()) 7677 return QualType(); 7678 7679 if (!LHS.get()->getType()->isScalarType() || 7680 !RHS.get()->getType()->isScalarType()) 7681 return InvalidOperands(Loc, LHS, RHS); 7682 7683 return Context.IntTy; 7684 } 7685 7686 // The following is safe because we only use this method for 7687 // non-overloadable operands. 7688 7689 // C++ [expr.log.and]p1 7690 // C++ [expr.log.or]p1 7691 // The operands are both contextually converted to type bool. 7692 ExprResult LHSRes = PerformContextuallyConvertToBool(LHS.get()); 7693 if (LHSRes.isInvalid()) 7694 return InvalidOperands(Loc, LHS, RHS); 7695 LHS = LHSRes; 7696 7697 ExprResult RHSRes = PerformContextuallyConvertToBool(RHS.get()); 7698 if (RHSRes.isInvalid()) 7699 return InvalidOperands(Loc, LHS, RHS); 7700 RHS = RHSRes; 7701 7702 // C++ [expr.log.and]p2 7703 // C++ [expr.log.or]p2 7704 // The result is a bool. 7705 return Context.BoolTy; 7706} 7707 7708/// IsReadonlyProperty - Verify that otherwise a valid l-value expression 7709/// is a read-only property; return true if so. A readonly property expression 7710/// depends on various declarations and thus must be treated specially. 7711/// 7712static bool IsReadonlyProperty(Expr *E, Sema &S) { 7713 const ObjCPropertyRefExpr *PropExpr = dyn_cast<ObjCPropertyRefExpr>(E); 7714 if (!PropExpr) return false; 7715 if (PropExpr->isImplicitProperty()) return false; 7716 7717 ObjCPropertyDecl *PDecl = PropExpr->getExplicitProperty(); 7718 QualType BaseType = PropExpr->isSuperReceiver() ? 7719 PropExpr->getSuperReceiverType() : 7720 PropExpr->getBase()->getType(); 7721 7722 if (const ObjCObjectPointerType *OPT = 7723 BaseType->getAsObjCInterfacePointerType()) 7724 if (ObjCInterfaceDecl *IFace = OPT->getInterfaceDecl()) 7725 if (S.isPropertyReadonly(PDecl, IFace)) 7726 return true; 7727 return false; 7728} 7729 7730static bool IsReadonlyMessage(Expr *E, Sema &S) { 7731 const MemberExpr *ME = dyn_cast<MemberExpr>(E); 7732 if (!ME) return false; 7733 if (!isa<FieldDecl>(ME->getMemberDecl())) return false; 7734 ObjCMessageExpr *Base = 7735 dyn_cast<ObjCMessageExpr>(ME->getBase()->IgnoreParenImpCasts()); 7736 if (!Base) return false; 7737 return Base->getMethodDecl() != 0; 7738} 7739 7740/// Is the given expression (which must be 'const') a reference to a 7741/// variable which was originally non-const, but which has become 7742/// 'const' due to being captured within a block? 7743enum NonConstCaptureKind { NCCK_None, NCCK_Block, NCCK_Lambda }; 7744static NonConstCaptureKind isReferenceToNonConstCapture(Sema &S, Expr *E) { 7745 assert(E->isLValue() && E->getType().isConstQualified()); 7746 E = E->IgnoreParens(); 7747 7748 // Must be a reference to a declaration from an enclosing scope. 7749 DeclRefExpr *DRE = dyn_cast<DeclRefExpr>(E); 7750 if (!DRE) return NCCK_None; 7751 if (!DRE->refersToEnclosingLocal()) return NCCK_None; 7752 7753 // The declaration must be a variable which is not declared 'const'. 7754 VarDecl *var = dyn_cast<VarDecl>(DRE->getDecl()); 7755 if (!var) return NCCK_None; 7756 if (var->getType().isConstQualified()) return NCCK_None; 7757 assert(var->hasLocalStorage() && "capture added 'const' to non-local?"); 7758 7759 // Decide whether the first capture was for a block or a lambda. 7760 DeclContext *DC = S.CurContext; 7761 while (DC->getParent() != var->getDeclContext()) 7762 DC = DC->getParent(); 7763 return (isa<BlockDecl>(DC) ? NCCK_Block : NCCK_Lambda); 7764} 7765 7766/// CheckForModifiableLvalue - Verify that E is a modifiable lvalue. If not, 7767/// emit an error and return true. If so, return false. 7768static bool CheckForModifiableLvalue(Expr *E, SourceLocation Loc, Sema &S) { 7769 assert(!E->hasPlaceholderType(BuiltinType::PseudoObject)); 7770 SourceLocation OrigLoc = Loc; 7771 Expr::isModifiableLvalueResult IsLV = E->isModifiableLvalue(S.Context, 7772 &Loc); 7773 if (IsLV == Expr::MLV_Valid && IsReadonlyProperty(E, S)) 7774 IsLV = Expr::MLV_ReadonlyProperty; 7775 else if (IsLV == Expr::MLV_ClassTemporary && IsReadonlyMessage(E, S)) 7776 IsLV = Expr::MLV_InvalidMessageExpression; 7777 if (IsLV == Expr::MLV_Valid) 7778 return false; 7779 7780 unsigned Diag = 0; 7781 bool NeedType = false; 7782 switch (IsLV) { // C99 6.5.16p2 7783 case Expr::MLV_ConstQualified: 7784 Diag = diag::err_typecheck_assign_const; 7785 7786 // Use a specialized diagnostic when we're assigning to an object 7787 // from an enclosing function or block. 7788 if (NonConstCaptureKind NCCK = isReferenceToNonConstCapture(S, E)) { 7789 if (NCCK == NCCK_Block) 7790 Diag = diag::err_block_decl_ref_not_modifiable_lvalue; 7791 else 7792 Diag = diag::err_lambda_decl_ref_not_modifiable_lvalue; 7793 break; 7794 } 7795 7796 // In ARC, use some specialized diagnostics for occasions where we 7797 // infer 'const'. These are always pseudo-strong variables. 7798 if (S.getLangOpts().ObjCAutoRefCount) { 7799 DeclRefExpr *declRef = dyn_cast<DeclRefExpr>(E->IgnoreParenCasts()); 7800 if (declRef && isa<VarDecl>(declRef->getDecl())) { 7801 VarDecl *var = cast<VarDecl>(declRef->getDecl()); 7802 7803 // Use the normal diagnostic if it's pseudo-__strong but the 7804 // user actually wrote 'const'. 7805 if (var->isARCPseudoStrong() && 7806 (!var->getTypeSourceInfo() || 7807 !var->getTypeSourceInfo()->getType().isConstQualified())) { 7808 // There are two pseudo-strong cases: 7809 // - self 7810 ObjCMethodDecl *method = S.getCurMethodDecl(); 7811 if (method && var == method->getSelfDecl()) 7812 Diag = method->isClassMethod() 7813 ? diag::err_typecheck_arc_assign_self_class_method 7814 : diag::err_typecheck_arc_assign_self; 7815 7816 // - fast enumeration variables 7817 else 7818 Diag = diag::err_typecheck_arr_assign_enumeration; 7819 7820 SourceRange Assign; 7821 if (Loc != OrigLoc) 7822 Assign = SourceRange(OrigLoc, OrigLoc); 7823 S.Diag(Loc, Diag) << E->getSourceRange() << Assign; 7824 // We need to preserve the AST regardless, so migration tool 7825 // can do its job. 7826 return false; 7827 } 7828 } 7829 } 7830 7831 break; 7832 case Expr::MLV_ArrayType: 7833 case Expr::MLV_ArrayTemporary: 7834 Diag = diag::err_typecheck_array_not_modifiable_lvalue; 7835 NeedType = true; 7836 break; 7837 case Expr::MLV_NotObjectType: 7838 Diag = diag::err_typecheck_non_object_not_modifiable_lvalue; 7839 NeedType = true; 7840 break; 7841 case Expr::MLV_LValueCast: 7842 Diag = diag::err_typecheck_lvalue_casts_not_supported; 7843 break; 7844 case Expr::MLV_Valid: 7845 llvm_unreachable("did not take early return for MLV_Valid"); 7846 case Expr::MLV_InvalidExpression: 7847 case Expr::MLV_MemberFunction: 7848 case Expr::MLV_ClassTemporary: 7849 Diag = diag::err_typecheck_expression_not_modifiable_lvalue; 7850 break; 7851 case Expr::MLV_IncompleteType: 7852 case Expr::MLV_IncompleteVoidType: 7853 return S.RequireCompleteType(Loc, E->getType(), 7854 diag::err_typecheck_incomplete_type_not_modifiable_lvalue, E); 7855 case Expr::MLV_DuplicateVectorComponents: 7856 Diag = diag::err_typecheck_duplicate_vector_components_not_mlvalue; 7857 break; 7858 case Expr::MLV_ReadonlyProperty: 7859 case Expr::MLV_NoSetterProperty: 7860 llvm_unreachable("readonly properties should be processed differently"); 7861 case Expr::MLV_InvalidMessageExpression: 7862 Diag = diag::error_readonly_message_assignment; 7863 break; 7864 case Expr::MLV_SubObjCPropertySetting: 7865 Diag = diag::error_no_subobject_property_setting; 7866 break; 7867 } 7868 7869 SourceRange Assign; 7870 if (Loc != OrigLoc) 7871 Assign = SourceRange(OrigLoc, OrigLoc); 7872 if (NeedType) 7873 S.Diag(Loc, Diag) << E->getType() << E->getSourceRange() << Assign; 7874 else 7875 S.Diag(Loc, Diag) << E->getSourceRange() << Assign; 7876 return true; 7877} 7878 7879static void CheckIdentityFieldAssignment(Expr *LHSExpr, Expr *RHSExpr, 7880 SourceLocation Loc, 7881 Sema &Sema) { 7882 // C / C++ fields 7883 MemberExpr *ML = dyn_cast<MemberExpr>(LHSExpr); 7884 MemberExpr *MR = dyn_cast<MemberExpr>(RHSExpr); 7885 if (ML && MR && ML->getMemberDecl() == MR->getMemberDecl()) { 7886 if (isa<CXXThisExpr>(ML->getBase()) && isa<CXXThisExpr>(MR->getBase())) 7887 Sema.Diag(Loc, diag::warn_identity_field_assign) << 0; 7888 } 7889 7890 // Objective-C instance variables 7891 ObjCIvarRefExpr *OL = dyn_cast<ObjCIvarRefExpr>(LHSExpr); 7892 ObjCIvarRefExpr *OR = dyn_cast<ObjCIvarRefExpr>(RHSExpr); 7893 if (OL && OR && OL->getDecl() == OR->getDecl()) { 7894 DeclRefExpr *RL = dyn_cast<DeclRefExpr>(OL->getBase()->IgnoreImpCasts()); 7895 DeclRefExpr *RR = dyn_cast<DeclRefExpr>(OR->getBase()->IgnoreImpCasts()); 7896 if (RL && RR && RL->getDecl() == RR->getDecl()) 7897 Sema.Diag(Loc, diag::warn_identity_field_assign) << 1; 7898 } 7899} 7900 7901// C99 6.5.16.1 7902QualType Sema::CheckAssignmentOperands(Expr *LHSExpr, ExprResult &RHS, 7903 SourceLocation Loc, 7904 QualType CompoundType) { 7905 assert(!LHSExpr->hasPlaceholderType(BuiltinType::PseudoObject)); 7906 7907 // Verify that LHS is a modifiable lvalue, and emit error if not. 7908 if (CheckForModifiableLvalue(LHSExpr, Loc, *this)) 7909 return QualType(); 7910 7911 QualType LHSType = LHSExpr->getType(); 7912 QualType RHSType = CompoundType.isNull() ? RHS.get()->getType() : 7913 CompoundType; 7914 AssignConvertType ConvTy; 7915 if (CompoundType.isNull()) { 7916 Expr *RHSCheck = RHS.get(); 7917 7918 CheckIdentityFieldAssignment(LHSExpr, RHSCheck, Loc, *this); 7919 7920 QualType LHSTy(LHSType); 7921 ConvTy = CheckSingleAssignmentConstraints(LHSTy, RHS); 7922 if (RHS.isInvalid()) 7923 return QualType(); 7924 // Special case of NSObject attributes on c-style pointer types. 7925 if (ConvTy == IncompatiblePointer && 7926 ((Context.isObjCNSObjectType(LHSType) && 7927 RHSType->isObjCObjectPointerType()) || 7928 (Context.isObjCNSObjectType(RHSType) && 7929 LHSType->isObjCObjectPointerType()))) 7930 ConvTy = Compatible; 7931 7932 if (ConvTy == Compatible && 7933 LHSType->isObjCObjectType()) 7934 Diag(Loc, diag::err_objc_object_assignment) 7935 << LHSType; 7936 7937 // If the RHS is a unary plus or minus, check to see if they = and + are 7938 // right next to each other. If so, the user may have typo'd "x =+ 4" 7939 // instead of "x += 4". 7940 if (ImplicitCastExpr *ICE = dyn_cast<ImplicitCastExpr>(RHSCheck)) 7941 RHSCheck = ICE->getSubExpr(); 7942 if (UnaryOperator *UO = dyn_cast<UnaryOperator>(RHSCheck)) { 7943 if ((UO->getOpcode() == UO_Plus || 7944 UO->getOpcode() == UO_Minus) && 7945 Loc.isFileID() && UO->getOperatorLoc().isFileID() && 7946 // Only if the two operators are exactly adjacent. 7947 Loc.getLocWithOffset(1) == UO->getOperatorLoc() && 7948 // And there is a space or other character before the subexpr of the 7949 // unary +/-. We don't want to warn on "x=-1". 7950 Loc.getLocWithOffset(2) != UO->getSubExpr()->getLocStart() && 7951 UO->getSubExpr()->getLocStart().isFileID()) { 7952 Diag(Loc, diag::warn_not_compound_assign) 7953 << (UO->getOpcode() == UO_Plus ? "+" : "-") 7954 << SourceRange(UO->getOperatorLoc(), UO->getOperatorLoc()); 7955 } 7956 } 7957 7958 if (ConvTy == Compatible) { 7959 if (LHSType.getObjCLifetime() == Qualifiers::OCL_Strong) { 7960 // Warn about retain cycles where a block captures the LHS, but 7961 // not if the LHS is a simple variable into which the block is 7962 // being stored...unless that variable can be captured by reference! 7963 const Expr *InnerLHS = LHSExpr->IgnoreParenCasts(); 7964 const DeclRefExpr *DRE = dyn_cast<DeclRefExpr>(InnerLHS); 7965 if (!DRE || DRE->getDecl()->hasAttr<BlocksAttr>()) 7966 checkRetainCycles(LHSExpr, RHS.get()); 7967 7968 // It is safe to assign a weak reference into a strong variable. 7969 // Although this code can still have problems: 7970 // id x = self.weakProp; 7971 // id y = self.weakProp; 7972 // we do not warn to warn spuriously when 'x' and 'y' are on separate 7973 // paths through the function. This should be revisited if 7974 // -Wrepeated-use-of-weak is made flow-sensitive. 7975 DiagnosticsEngine::Level Level = 7976 Diags.getDiagnosticLevel(diag::warn_arc_repeated_use_of_weak, 7977 RHS.get()->getLocStart()); 7978 if (Level != DiagnosticsEngine::Ignored) 7979 getCurFunction()->markSafeWeakUse(RHS.get()); 7980 7981 } else if (getLangOpts().ObjCAutoRefCount) { 7982 checkUnsafeExprAssigns(Loc, LHSExpr, RHS.get()); 7983 } 7984 } 7985 } else { 7986 // Compound assignment "x += y" 7987 ConvTy = CheckAssignmentConstraints(Loc, LHSType, RHSType); 7988 } 7989 7990 if (DiagnoseAssignmentResult(ConvTy, Loc, LHSType, RHSType, 7991 RHS.get(), AA_Assigning)) 7992 return QualType(); 7993 7994 CheckForNullPointerDereference(*this, LHSExpr); 7995 7996 // C99 6.5.16p3: The type of an assignment expression is the type of the 7997 // left operand unless the left operand has qualified type, in which case 7998 // it is the unqualified version of the type of the left operand. 7999 // C99 6.5.16.1p2: In simple assignment, the value of the right operand 8000 // is converted to the type of the assignment expression (above). 8001 // C++ 5.17p1: the type of the assignment expression is that of its left 8002 // operand. 8003 return (getLangOpts().CPlusPlus 8004 ? LHSType : LHSType.getUnqualifiedType()); 8005} 8006 8007// C99 6.5.17 8008static QualType CheckCommaOperands(Sema &S, ExprResult &LHS, ExprResult &RHS, 8009 SourceLocation Loc) { 8010 LHS = S.CheckPlaceholderExpr(LHS.take()); 8011 RHS = S.CheckPlaceholderExpr(RHS.take()); 8012 if (LHS.isInvalid() || RHS.isInvalid()) 8013 return QualType(); 8014 8015 // C's comma performs lvalue conversion (C99 6.3.2.1) on both its 8016 // operands, but not unary promotions. 8017 // C++'s comma does not do any conversions at all (C++ [expr.comma]p1). 8018 8019 // So we treat the LHS as a ignored value, and in C++ we allow the 8020 // containing site to determine what should be done with the RHS. 8021 LHS = S.IgnoredValueConversions(LHS.take()); 8022 if (LHS.isInvalid()) 8023 return QualType(); 8024 8025 S.DiagnoseUnusedExprResult(LHS.get()); 8026 8027 if (!S.getLangOpts().CPlusPlus) { 8028 RHS = S.DefaultFunctionArrayLvalueConversion(RHS.take()); 8029 if (RHS.isInvalid()) 8030 return QualType(); 8031 if (!RHS.get()->getType()->isVoidType()) 8032 S.RequireCompleteType(Loc, RHS.get()->getType(), 8033 diag::err_incomplete_type); 8034 } 8035 8036 return RHS.get()->getType(); 8037} 8038 8039/// CheckIncrementDecrementOperand - unlike most "Check" methods, this routine 8040/// doesn't need to call UsualUnaryConversions or UsualArithmeticConversions. 8041static QualType CheckIncrementDecrementOperand(Sema &S, Expr *Op, 8042 ExprValueKind &VK, 8043 SourceLocation OpLoc, 8044 bool IsInc, bool IsPrefix) { 8045 if (Op->isTypeDependent()) 8046 return S.Context.DependentTy; 8047 8048 QualType ResType = Op->getType(); 8049 // Atomic types can be used for increment / decrement where the non-atomic 8050 // versions can, so ignore the _Atomic() specifier for the purpose of 8051 // checking. 8052 if (const AtomicType *ResAtomicType = ResType->getAs<AtomicType>()) 8053 ResType = ResAtomicType->getValueType(); 8054 8055 assert(!ResType.isNull() && "no type for increment/decrement expression"); 8056 8057 if (S.getLangOpts().CPlusPlus && ResType->isBooleanType()) { 8058 // Decrement of bool is not allowed. 8059 if (!IsInc) { 8060 S.Diag(OpLoc, diag::err_decrement_bool) << Op->getSourceRange(); 8061 return QualType(); 8062 } 8063 // Increment of bool sets it to true, but is deprecated. 8064 S.Diag(OpLoc, diag::warn_increment_bool) << Op->getSourceRange(); 8065 } else if (ResType->isRealType()) { 8066 // OK! 8067 } else if (ResType->isPointerType()) { 8068 // C99 6.5.2.4p2, 6.5.6p2 8069 if (!checkArithmeticOpPointerOperand(S, OpLoc, Op)) 8070 return QualType(); 8071 } else if (ResType->isObjCObjectPointerType()) { 8072 // On modern runtimes, ObjC pointer arithmetic is forbidden. 8073 // Otherwise, we just need a complete type. 8074 if (checkArithmeticIncompletePointerType(S, OpLoc, Op) || 8075 checkArithmeticOnObjCPointer(S, OpLoc, Op)) 8076 return QualType(); 8077 } else if (ResType->isAnyComplexType()) { 8078 // C99 does not support ++/-- on complex types, we allow as an extension. 8079 S.Diag(OpLoc, diag::ext_integer_increment_complex) 8080 << ResType << Op->getSourceRange(); 8081 } else if (ResType->isPlaceholderType()) { 8082 ExprResult PR = S.CheckPlaceholderExpr(Op); 8083 if (PR.isInvalid()) return QualType(); 8084 return CheckIncrementDecrementOperand(S, PR.take(), VK, OpLoc, 8085 IsInc, IsPrefix); 8086 } else if (S.getLangOpts().AltiVec && ResType->isVectorType()) { 8087 // OK! ( C/C++ Language Extensions for CBEA(Version 2.6) 10.3 ) 8088 } else { 8089 S.Diag(OpLoc, diag::err_typecheck_illegal_increment_decrement) 8090 << ResType << int(IsInc) << Op->getSourceRange(); 8091 return QualType(); 8092 } 8093 // At this point, we know we have a real, complex or pointer type. 8094 // Now make sure the operand is a modifiable lvalue. 8095 if (CheckForModifiableLvalue(Op, OpLoc, S)) 8096 return QualType(); 8097 // In C++, a prefix increment is the same type as the operand. Otherwise 8098 // (in C or with postfix), the increment is the unqualified type of the 8099 // operand. 8100 if (IsPrefix && S.getLangOpts().CPlusPlus) { 8101 VK = VK_LValue; 8102 return ResType; 8103 } else { 8104 VK = VK_RValue; 8105 return ResType.getUnqualifiedType(); 8106 } 8107} 8108 8109 8110/// getPrimaryDecl - Helper function for CheckAddressOfOperand(). 8111/// This routine allows us to typecheck complex/recursive expressions 8112/// where the declaration is needed for type checking. We only need to 8113/// handle cases when the expression references a function designator 8114/// or is an lvalue. Here are some examples: 8115/// - &(x) => x 8116/// - &*****f => f for f a function designator. 8117/// - &s.xx => s 8118/// - &s.zz[1].yy -> s, if zz is an array 8119/// - *(x + 1) -> x, if x is an array 8120/// - &"123"[2] -> 0 8121/// - & __real__ x -> x 8122static ValueDecl *getPrimaryDecl(Expr *E) { 8123 switch (E->getStmtClass()) { 8124 case Stmt::DeclRefExprClass: 8125 return cast<DeclRefExpr>(E)->getDecl(); 8126 case Stmt::MemberExprClass: 8127 // If this is an arrow operator, the address is an offset from 8128 // the base's value, so the object the base refers to is 8129 // irrelevant. 8130 if (cast<MemberExpr>(E)->isArrow()) 8131 return 0; 8132 // Otherwise, the expression refers to a part of the base 8133 return getPrimaryDecl(cast<MemberExpr>(E)->getBase()); 8134 case Stmt::ArraySubscriptExprClass: { 8135 // FIXME: This code shouldn't be necessary! We should catch the implicit 8136 // promotion of register arrays earlier. 8137 Expr* Base = cast<ArraySubscriptExpr>(E)->getBase(); 8138 if (ImplicitCastExpr* ICE = dyn_cast<ImplicitCastExpr>(Base)) { 8139 if (ICE->getSubExpr()->getType()->isArrayType()) 8140 return getPrimaryDecl(ICE->getSubExpr()); 8141 } 8142 return 0; 8143 } 8144 case Stmt::UnaryOperatorClass: { 8145 UnaryOperator *UO = cast<UnaryOperator>(E); 8146 8147 switch(UO->getOpcode()) { 8148 case UO_Real: 8149 case UO_Imag: 8150 case UO_Extension: 8151 return getPrimaryDecl(UO->getSubExpr()); 8152 default: 8153 return 0; 8154 } 8155 } 8156 case Stmt::ParenExprClass: 8157 return getPrimaryDecl(cast<ParenExpr>(E)->getSubExpr()); 8158 case Stmt::ImplicitCastExprClass: 8159 // If the result of an implicit cast is an l-value, we care about 8160 // the sub-expression; otherwise, the result here doesn't matter. 8161 return getPrimaryDecl(cast<ImplicitCastExpr>(E)->getSubExpr()); 8162 default: 8163 return 0; 8164 } 8165} 8166 8167namespace { 8168 enum { 8169 AO_Bit_Field = 0, 8170 AO_Vector_Element = 1, 8171 AO_Property_Expansion = 2, 8172 AO_Register_Variable = 3, 8173 AO_No_Error = 4 8174 }; 8175} 8176/// \brief Diagnose invalid operand for address of operations. 8177/// 8178/// \param Type The type of operand which cannot have its address taken. 8179static void diagnoseAddressOfInvalidType(Sema &S, SourceLocation Loc, 8180 Expr *E, unsigned Type) { 8181 S.Diag(Loc, diag::err_typecheck_address_of) << Type << E->getSourceRange(); 8182} 8183 8184/// CheckAddressOfOperand - The operand of & must be either a function 8185/// designator or an lvalue designating an object. If it is an lvalue, the 8186/// object cannot be declared with storage class register or be a bit field. 8187/// Note: The usual conversions are *not* applied to the operand of the & 8188/// operator (C99 6.3.2.1p[2-4]), and its result is never an lvalue. 8189/// In C++, the operand might be an overloaded function name, in which case 8190/// we allow the '&' but retain the overloaded-function type. 8191static QualType CheckAddressOfOperand(Sema &S, ExprResult &OrigOp, 8192 SourceLocation OpLoc) { 8193 if (const BuiltinType *PTy = OrigOp.get()->getType()->getAsPlaceholderType()){ 8194 if (PTy->getKind() == BuiltinType::Overload) { 8195 if (!isa<OverloadExpr>(OrigOp.get()->IgnoreParens())) { 8196 assert(cast<UnaryOperator>(OrigOp.get()->IgnoreParens())->getOpcode() 8197 == UO_AddrOf); 8198 S.Diag(OpLoc, diag::err_typecheck_invalid_lvalue_addrof_addrof_function) 8199 << OrigOp.get()->getSourceRange(); 8200 return QualType(); 8201 } 8202 8203 return S.Context.OverloadTy; 8204 } 8205 8206 if (PTy->getKind() == BuiltinType::UnknownAny) 8207 return S.Context.UnknownAnyTy; 8208 8209 if (PTy->getKind() == BuiltinType::BoundMember) { 8210 S.Diag(OpLoc, diag::err_invalid_form_pointer_member_function) 8211 << OrigOp.get()->getSourceRange(); 8212 return QualType(); 8213 } 8214 8215 OrigOp = S.CheckPlaceholderExpr(OrigOp.take()); 8216 if (OrigOp.isInvalid()) return QualType(); 8217 } 8218 8219 if (OrigOp.get()->isTypeDependent()) 8220 return S.Context.DependentTy; 8221 8222 assert(!OrigOp.get()->getType()->isPlaceholderType()); 8223 8224 // Make sure to ignore parentheses in subsequent checks 8225 Expr *op = OrigOp.get()->IgnoreParens(); 8226 8227 if (S.getLangOpts().C99) { 8228 // Implement C99-only parts of addressof rules. 8229 if (UnaryOperator* uOp = dyn_cast<UnaryOperator>(op)) { 8230 if (uOp->getOpcode() == UO_Deref) 8231 // Per C99 6.5.3.2, the address of a deref always returns a valid result 8232 // (assuming the deref expression is valid). 8233 return uOp->getSubExpr()->getType(); 8234 } 8235 // Technically, there should be a check for array subscript 8236 // expressions here, but the result of one is always an lvalue anyway. 8237 } 8238 ValueDecl *dcl = getPrimaryDecl(op); 8239 Expr::LValueClassification lval = op->ClassifyLValue(S.Context); 8240 unsigned AddressOfError = AO_No_Error; 8241 8242 if (lval == Expr::LV_ClassTemporary || lval == Expr::LV_ArrayTemporary) { 8243 bool sfinae = (bool)S.isSFINAEContext(); 8244 S.Diag(OpLoc, S.isSFINAEContext() ? diag::err_typecheck_addrof_temporary 8245 : diag::ext_typecheck_addrof_temporary) 8246 << op->getType() << op->getSourceRange(); 8247 if (sfinae) 8248 return QualType(); 8249 } else if (isa<ObjCSelectorExpr>(op)) { 8250 return S.Context.getPointerType(op->getType()); 8251 } else if (lval == Expr::LV_MemberFunction) { 8252 // If it's an instance method, make a member pointer. 8253 // The expression must have exactly the form &A::foo. 8254 8255 // If the underlying expression isn't a decl ref, give up. 8256 if (!isa<DeclRefExpr>(op)) { 8257 S.Diag(OpLoc, diag::err_invalid_form_pointer_member_function) 8258 << OrigOp.get()->getSourceRange(); 8259 return QualType(); 8260 } 8261 DeclRefExpr *DRE = cast<DeclRefExpr>(op); 8262 CXXMethodDecl *MD = cast<CXXMethodDecl>(DRE->getDecl()); 8263 8264 // The id-expression was parenthesized. 8265 if (OrigOp.get() != DRE) { 8266 S.Diag(OpLoc, diag::err_parens_pointer_member_function) 8267 << OrigOp.get()->getSourceRange(); 8268 8269 // The method was named without a qualifier. 8270 } else if (!DRE->getQualifier()) { 8271 if (MD->getParent()->getName().empty()) 8272 S.Diag(OpLoc, diag::err_unqualified_pointer_member_function) 8273 << op->getSourceRange(); 8274 else { 8275 SmallString<32> Str; 8276 StringRef Qual = (MD->getParent()->getName() + "::").toStringRef(Str); 8277 S.Diag(OpLoc, diag::err_unqualified_pointer_member_function) 8278 << op->getSourceRange() 8279 << FixItHint::CreateInsertion(op->getSourceRange().getBegin(), Qual); 8280 } 8281 } 8282 8283 return S.Context.getMemberPointerType(op->getType(), 8284 S.Context.getTypeDeclType(MD->getParent()).getTypePtr()); 8285 } else if (lval != Expr::LV_Valid && lval != Expr::LV_IncompleteVoidType) { 8286 // C99 6.5.3.2p1 8287 // The operand must be either an l-value or a function designator 8288 if (!op->getType()->isFunctionType()) { 8289 // Use a special diagnostic for loads from property references. 8290 if (isa<PseudoObjectExpr>(op)) { 8291 AddressOfError = AO_Property_Expansion; 8292 } else { 8293 S.Diag(OpLoc, diag::err_typecheck_invalid_lvalue_addrof) 8294 << op->getType() << op->getSourceRange(); 8295 return QualType(); 8296 } 8297 } 8298 } else if (op->getObjectKind() == OK_BitField) { // C99 6.5.3.2p1 8299 // The operand cannot be a bit-field 8300 AddressOfError = AO_Bit_Field; 8301 } else if (op->getObjectKind() == OK_VectorComponent) { 8302 // The operand cannot be an element of a vector 8303 AddressOfError = AO_Vector_Element; 8304 } else if (dcl) { // C99 6.5.3.2p1 8305 // We have an lvalue with a decl. Make sure the decl is not declared 8306 // with the register storage-class specifier. 8307 if (const VarDecl *vd = dyn_cast<VarDecl>(dcl)) { 8308 // in C++ it is not error to take address of a register 8309 // variable (c++03 7.1.1P3) 8310 if (vd->getStorageClass() == SC_Register && 8311 !S.getLangOpts().CPlusPlus) { 8312 AddressOfError = AO_Register_Variable; 8313 } 8314 } else if (isa<FunctionTemplateDecl>(dcl)) { 8315 return S.Context.OverloadTy; 8316 } else if (isa<FieldDecl>(dcl) || isa<IndirectFieldDecl>(dcl)) { 8317 // Okay: we can take the address of a field. 8318 // Could be a pointer to member, though, if there is an explicit 8319 // scope qualifier for the class. 8320 if (isa<DeclRefExpr>(op) && cast<DeclRefExpr>(op)->getQualifier()) { 8321 DeclContext *Ctx = dcl->getDeclContext(); 8322 if (Ctx && Ctx->isRecord()) { 8323 if (dcl->getType()->isReferenceType()) { 8324 S.Diag(OpLoc, 8325 diag::err_cannot_form_pointer_to_member_of_reference_type) 8326 << dcl->getDeclName() << dcl->getType(); 8327 return QualType(); 8328 } 8329 8330 while (cast<RecordDecl>(Ctx)->isAnonymousStructOrUnion()) 8331 Ctx = Ctx->getParent(); 8332 return S.Context.getMemberPointerType(op->getType(), 8333 S.Context.getTypeDeclType(cast<RecordDecl>(Ctx)).getTypePtr()); 8334 } 8335 } 8336 } else if (!isa<FunctionDecl>(dcl) && !isa<NonTypeTemplateParmDecl>(dcl)) 8337 llvm_unreachable("Unknown/unexpected decl type"); 8338 } 8339 8340 if (AddressOfError != AO_No_Error) { 8341 diagnoseAddressOfInvalidType(S, OpLoc, op, AddressOfError); 8342 return QualType(); 8343 } 8344 8345 if (lval == Expr::LV_IncompleteVoidType) { 8346 // Taking the address of a void variable is technically illegal, but we 8347 // allow it in cases which are otherwise valid. 8348 // Example: "extern void x; void* y = &x;". 8349 S.Diag(OpLoc, diag::ext_typecheck_addrof_void) << op->getSourceRange(); 8350 } 8351 8352 // If the operand has type "type", the result has type "pointer to type". 8353 if (op->getType()->isObjCObjectType()) 8354 return S.Context.getObjCObjectPointerType(op->getType()); 8355 return S.Context.getPointerType(op->getType()); 8356} 8357 8358/// CheckIndirectionOperand - Type check unary indirection (prefix '*'). 8359static QualType CheckIndirectionOperand(Sema &S, Expr *Op, ExprValueKind &VK, 8360 SourceLocation OpLoc) { 8361 if (Op->isTypeDependent()) 8362 return S.Context.DependentTy; 8363 8364 ExprResult ConvResult = S.UsualUnaryConversions(Op); 8365 if (ConvResult.isInvalid()) 8366 return QualType(); 8367 Op = ConvResult.take(); 8368 QualType OpTy = Op->getType(); 8369 QualType Result; 8370 8371 if (isa<CXXReinterpretCastExpr>(Op)) { 8372 QualType OpOrigType = Op->IgnoreParenCasts()->getType(); 8373 S.CheckCompatibleReinterpretCast(OpOrigType, OpTy, /*IsDereference*/true, 8374 Op->getSourceRange()); 8375 } 8376 8377 // Note that per both C89 and C99, indirection is always legal, even if OpTy 8378 // is an incomplete type or void. It would be possible to warn about 8379 // dereferencing a void pointer, but it's completely well-defined, and such a 8380 // warning is unlikely to catch any mistakes. 8381 if (const PointerType *PT = OpTy->getAs<PointerType>()) 8382 Result = PT->getPointeeType(); 8383 else if (const ObjCObjectPointerType *OPT = 8384 OpTy->getAs<ObjCObjectPointerType>()) 8385 Result = OPT->getPointeeType(); 8386 else { 8387 ExprResult PR = S.CheckPlaceholderExpr(Op); 8388 if (PR.isInvalid()) return QualType(); 8389 if (PR.take() != Op) 8390 return CheckIndirectionOperand(S, PR.take(), VK, OpLoc); 8391 } 8392 8393 if (Result.isNull()) { 8394 S.Diag(OpLoc, diag::err_typecheck_indirection_requires_pointer) 8395 << OpTy << Op->getSourceRange(); 8396 return QualType(); 8397 } 8398 8399 // Dereferences are usually l-values... 8400 VK = VK_LValue; 8401 8402 // ...except that certain expressions are never l-values in C. 8403 if (!S.getLangOpts().CPlusPlus && Result.isCForbiddenLValueType()) 8404 VK = VK_RValue; 8405 8406 return Result; 8407} 8408 8409static inline BinaryOperatorKind ConvertTokenKindToBinaryOpcode( 8410 tok::TokenKind Kind) { 8411 BinaryOperatorKind Opc; 8412 switch (Kind) { 8413 default: llvm_unreachable("Unknown binop!"); 8414 case tok::periodstar: Opc = BO_PtrMemD; break; 8415 case tok::arrowstar: Opc = BO_PtrMemI; break; 8416 case tok::star: Opc = BO_Mul; break; 8417 case tok::slash: Opc = BO_Div; break; 8418 case tok::percent: Opc = BO_Rem; break; 8419 case tok::plus: Opc = BO_Add; break; 8420 case tok::minus: Opc = BO_Sub; break; 8421 case tok::lessless: Opc = BO_Shl; break; 8422 case tok::greatergreater: Opc = BO_Shr; break; 8423 case tok::lessequal: Opc = BO_LE; break; 8424 case tok::less: Opc = BO_LT; break; 8425 case tok::greaterequal: Opc = BO_GE; break; 8426 case tok::greater: Opc = BO_GT; break; 8427 case tok::exclaimequal: Opc = BO_NE; break; 8428 case tok::equalequal: Opc = BO_EQ; break; 8429 case tok::amp: Opc = BO_And; break; 8430 case tok::caret: Opc = BO_Xor; break; 8431 case tok::pipe: Opc = BO_Or; break; 8432 case tok::ampamp: Opc = BO_LAnd; break; 8433 case tok::pipepipe: Opc = BO_LOr; break; 8434 case tok::equal: Opc = BO_Assign; break; 8435 case tok::starequal: Opc = BO_MulAssign; break; 8436 case tok::slashequal: Opc = BO_DivAssign; break; 8437 case tok::percentequal: Opc = BO_RemAssign; break; 8438 case tok::plusequal: Opc = BO_AddAssign; break; 8439 case tok::minusequal: Opc = BO_SubAssign; break; 8440 case tok::lesslessequal: Opc = BO_ShlAssign; break; 8441 case tok::greatergreaterequal: Opc = BO_ShrAssign; break; 8442 case tok::ampequal: Opc = BO_AndAssign; break; 8443 case tok::caretequal: Opc = BO_XorAssign; break; 8444 case tok::pipeequal: Opc = BO_OrAssign; break; 8445 case tok::comma: Opc = BO_Comma; break; 8446 } 8447 return Opc; 8448} 8449 8450static inline UnaryOperatorKind ConvertTokenKindToUnaryOpcode( 8451 tok::TokenKind Kind) { 8452 UnaryOperatorKind Opc; 8453 switch (Kind) { 8454 default: llvm_unreachable("Unknown unary op!"); 8455 case tok::plusplus: Opc = UO_PreInc; break; 8456 case tok::minusminus: Opc = UO_PreDec; break; 8457 case tok::amp: Opc = UO_AddrOf; break; 8458 case tok::star: Opc = UO_Deref; break; 8459 case tok::plus: Opc = UO_Plus; break; 8460 case tok::minus: Opc = UO_Minus; break; 8461 case tok::tilde: Opc = UO_Not; break; 8462 case tok::exclaim: Opc = UO_LNot; break; 8463 case tok::kw___real: Opc = UO_Real; break; 8464 case tok::kw___imag: Opc = UO_Imag; break; 8465 case tok::kw___extension__: Opc = UO_Extension; break; 8466 } 8467 return Opc; 8468} 8469 8470/// DiagnoseSelfAssignment - Emits a warning if a value is assigned to itself. 8471/// This warning is only emitted for builtin assignment operations. It is also 8472/// suppressed in the event of macro expansions. 8473static void DiagnoseSelfAssignment(Sema &S, Expr *LHSExpr, Expr *RHSExpr, 8474 SourceLocation OpLoc) { 8475 if (!S.ActiveTemplateInstantiations.empty()) 8476 return; 8477 if (OpLoc.isInvalid() || OpLoc.isMacroID()) 8478 return; 8479 LHSExpr = LHSExpr->IgnoreParenImpCasts(); 8480 RHSExpr = RHSExpr->IgnoreParenImpCasts(); 8481 const DeclRefExpr *LHSDeclRef = dyn_cast<DeclRefExpr>(LHSExpr); 8482 const DeclRefExpr *RHSDeclRef = dyn_cast<DeclRefExpr>(RHSExpr); 8483 if (!LHSDeclRef || !RHSDeclRef || 8484 LHSDeclRef->getLocation().isMacroID() || 8485 RHSDeclRef->getLocation().isMacroID()) 8486 return; 8487 const ValueDecl *LHSDecl = 8488 cast<ValueDecl>(LHSDeclRef->getDecl()->getCanonicalDecl()); 8489 const ValueDecl *RHSDecl = 8490 cast<ValueDecl>(RHSDeclRef->getDecl()->getCanonicalDecl()); 8491 if (LHSDecl != RHSDecl) 8492 return; 8493 if (LHSDecl->getType().isVolatileQualified()) 8494 return; 8495 if (const ReferenceType *RefTy = LHSDecl->getType()->getAs<ReferenceType>()) 8496 if (RefTy->getPointeeType().isVolatileQualified()) 8497 return; 8498 8499 S.Diag(OpLoc, diag::warn_self_assignment) 8500 << LHSDeclRef->getType() 8501 << LHSExpr->getSourceRange() << RHSExpr->getSourceRange(); 8502} 8503 8504/// CreateBuiltinBinOp - Creates a new built-in binary operation with 8505/// operator @p Opc at location @c TokLoc. This routine only supports 8506/// built-in operations; ActOnBinOp handles overloaded operators. 8507ExprResult Sema::CreateBuiltinBinOp(SourceLocation OpLoc, 8508 BinaryOperatorKind Opc, 8509 Expr *LHSExpr, Expr *RHSExpr) { 8510 if (getLangOpts().CPlusPlus11 && isa<InitListExpr>(RHSExpr)) { 8511 // The syntax only allows initializer lists on the RHS of assignment, 8512 // so we don't need to worry about accepting invalid code for 8513 // non-assignment operators. 8514 // C++11 5.17p9: 8515 // The meaning of x = {v} [...] is that of x = T(v) [...]. The meaning 8516 // of x = {} is x = T(). 8517 InitializationKind Kind = 8518 InitializationKind::CreateDirectList(RHSExpr->getLocStart()); 8519 InitializedEntity Entity = 8520 InitializedEntity::InitializeTemporary(LHSExpr->getType()); 8521 InitializationSequence InitSeq(*this, Entity, Kind, &RHSExpr, 1); 8522 ExprResult Init = InitSeq.Perform(*this, Entity, Kind, RHSExpr); 8523 if (Init.isInvalid()) 8524 return Init; 8525 RHSExpr = Init.take(); 8526 } 8527 8528 ExprResult LHS = Owned(LHSExpr), RHS = Owned(RHSExpr); 8529 QualType ResultTy; // Result type of the binary operator. 8530 // The following two variables are used for compound assignment operators 8531 QualType CompLHSTy; // Type of LHS after promotions for computation 8532 QualType CompResultTy; // Type of computation result 8533 ExprValueKind VK = VK_RValue; 8534 ExprObjectKind OK = OK_Ordinary; 8535 8536 switch (Opc) { 8537 case BO_Assign: 8538 ResultTy = CheckAssignmentOperands(LHS.get(), RHS, OpLoc, QualType()); 8539 if (getLangOpts().CPlusPlus && 8540 LHS.get()->getObjectKind() != OK_ObjCProperty) { 8541 VK = LHS.get()->getValueKind(); 8542 OK = LHS.get()->getObjectKind(); 8543 } 8544 if (!ResultTy.isNull()) 8545 DiagnoseSelfAssignment(*this, LHS.get(), RHS.get(), OpLoc); 8546 break; 8547 case BO_PtrMemD: 8548 case BO_PtrMemI: 8549 ResultTy = CheckPointerToMemberOperands(LHS, RHS, VK, OpLoc, 8550 Opc == BO_PtrMemI); 8551 break; 8552 case BO_Mul: 8553 case BO_Div: 8554 ResultTy = CheckMultiplyDivideOperands(LHS, RHS, OpLoc, false, 8555 Opc == BO_Div); 8556 break; 8557 case BO_Rem: 8558 ResultTy = CheckRemainderOperands(LHS, RHS, OpLoc); 8559 break; 8560 case BO_Add: 8561 ResultTy = CheckAdditionOperands(LHS, RHS, OpLoc, Opc); 8562 break; 8563 case BO_Sub: 8564 ResultTy = CheckSubtractionOperands(LHS, RHS, OpLoc); 8565 break; 8566 case BO_Shl: 8567 case BO_Shr: 8568 ResultTy = CheckShiftOperands(LHS, RHS, OpLoc, Opc); 8569 break; 8570 case BO_LE: 8571 case BO_LT: 8572 case BO_GE: 8573 case BO_GT: 8574 ResultTy = CheckCompareOperands(LHS, RHS, OpLoc, Opc, true); 8575 break; 8576 case BO_EQ: 8577 case BO_NE: 8578 ResultTy = CheckCompareOperands(LHS, RHS, OpLoc, Opc, false); 8579 break; 8580 case BO_And: 8581 case BO_Xor: 8582 case BO_Or: 8583 ResultTy = CheckBitwiseOperands(LHS, RHS, OpLoc); 8584 break; 8585 case BO_LAnd: 8586 case BO_LOr: 8587 ResultTy = CheckLogicalOperands(LHS, RHS, OpLoc, Opc); 8588 break; 8589 case BO_MulAssign: 8590 case BO_DivAssign: 8591 CompResultTy = CheckMultiplyDivideOperands(LHS, RHS, OpLoc, true, 8592 Opc == BO_DivAssign); 8593 CompLHSTy = CompResultTy; 8594 if (!CompResultTy.isNull() && !LHS.isInvalid() && !RHS.isInvalid()) 8595 ResultTy = CheckAssignmentOperands(LHS.get(), RHS, OpLoc, CompResultTy); 8596 break; 8597 case BO_RemAssign: 8598 CompResultTy = CheckRemainderOperands(LHS, RHS, OpLoc, true); 8599 CompLHSTy = CompResultTy; 8600 if (!CompResultTy.isNull() && !LHS.isInvalid() && !RHS.isInvalid()) 8601 ResultTy = CheckAssignmentOperands(LHS.get(), RHS, OpLoc, CompResultTy); 8602 break; 8603 case BO_AddAssign: 8604 CompResultTy = CheckAdditionOperands(LHS, RHS, OpLoc, Opc, &CompLHSTy); 8605 if (!CompResultTy.isNull() && !LHS.isInvalid() && !RHS.isInvalid()) 8606 ResultTy = CheckAssignmentOperands(LHS.get(), RHS, OpLoc, CompResultTy); 8607 break; 8608 case BO_SubAssign: 8609 CompResultTy = CheckSubtractionOperands(LHS, RHS, OpLoc, &CompLHSTy); 8610 if (!CompResultTy.isNull() && !LHS.isInvalid() && !RHS.isInvalid()) 8611 ResultTy = CheckAssignmentOperands(LHS.get(), RHS, OpLoc, CompResultTy); 8612 break; 8613 case BO_ShlAssign: 8614 case BO_ShrAssign: 8615 CompResultTy = CheckShiftOperands(LHS, RHS, OpLoc, Opc, true); 8616 CompLHSTy = CompResultTy; 8617 if (!CompResultTy.isNull() && !LHS.isInvalid() && !RHS.isInvalid()) 8618 ResultTy = CheckAssignmentOperands(LHS.get(), RHS, OpLoc, CompResultTy); 8619 break; 8620 case BO_AndAssign: 8621 case BO_XorAssign: 8622 case BO_OrAssign: 8623 CompResultTy = CheckBitwiseOperands(LHS, RHS, OpLoc, true); 8624 CompLHSTy = CompResultTy; 8625 if (!CompResultTy.isNull() && !LHS.isInvalid() && !RHS.isInvalid()) 8626 ResultTy = CheckAssignmentOperands(LHS.get(), RHS, OpLoc, CompResultTy); 8627 break; 8628 case BO_Comma: 8629 ResultTy = CheckCommaOperands(*this, LHS, RHS, OpLoc); 8630 if (getLangOpts().CPlusPlus && !RHS.isInvalid()) { 8631 VK = RHS.get()->getValueKind(); 8632 OK = RHS.get()->getObjectKind(); 8633 } 8634 break; 8635 } 8636 if (ResultTy.isNull() || LHS.isInvalid() || RHS.isInvalid()) 8637 return ExprError(); 8638 8639 // Check for array bounds violations for both sides of the BinaryOperator 8640 CheckArrayAccess(LHS.get()); 8641 CheckArrayAccess(RHS.get()); 8642 8643 if (const ObjCIsaExpr *OISA = dyn_cast<ObjCIsaExpr>(LHS.get()->IgnoreParenCasts())) { 8644 NamedDecl *ObjectSetClass = LookupSingleName(TUScope, 8645 &Context.Idents.get("object_setClass"), 8646 SourceLocation(), LookupOrdinaryName); 8647 if (ObjectSetClass && isa<ObjCIsaExpr>(LHS.get())) { 8648 SourceLocation RHSLocEnd = PP.getLocForEndOfToken(RHS.get()->getLocEnd()); 8649 Diag(LHS.get()->getExprLoc(), diag::warn_objc_isa_assign) << 8650 FixItHint::CreateInsertion(LHS.get()->getLocStart(), "object_setClass(") << 8651 FixItHint::CreateReplacement(SourceRange(OISA->getOpLoc(), OpLoc), ",") << 8652 FixItHint::CreateInsertion(RHSLocEnd, ")"); 8653 } 8654 else 8655 Diag(LHS.get()->getExprLoc(), diag::warn_objc_isa_assign); 8656 } 8657 else if (const ObjCIvarRefExpr *OIRE = 8658 dyn_cast<ObjCIvarRefExpr>(LHS.get()->IgnoreParenCasts())) 8659 DiagnoseDirectIsaAccess(*this, OIRE, OpLoc, RHS.get()); 8660 8661 if (CompResultTy.isNull()) 8662 return Owned(new (Context) BinaryOperator(LHS.take(), RHS.take(), Opc, 8663 ResultTy, VK, OK, OpLoc, 8664 FPFeatures.fp_contract)); 8665 if (getLangOpts().CPlusPlus && LHS.get()->getObjectKind() != 8666 OK_ObjCProperty) { 8667 VK = VK_LValue; 8668 OK = LHS.get()->getObjectKind(); 8669 } 8670 return Owned(new (Context) CompoundAssignOperator(LHS.take(), RHS.take(), Opc, 8671 ResultTy, VK, OK, CompLHSTy, 8672 CompResultTy, OpLoc, 8673 FPFeatures.fp_contract)); 8674} 8675 8676/// DiagnoseBitwisePrecedence - Emit a warning when bitwise and comparison 8677/// operators are mixed in a way that suggests that the programmer forgot that 8678/// comparison operators have higher precedence. The most typical example of 8679/// such code is "flags & 0x0020 != 0", which is equivalent to "flags & 1". 8680static void DiagnoseBitwisePrecedence(Sema &Self, BinaryOperatorKind Opc, 8681 SourceLocation OpLoc, Expr *LHSExpr, 8682 Expr *RHSExpr) { 8683 BinaryOperator *LHSBO = dyn_cast<BinaryOperator>(LHSExpr); 8684 BinaryOperator *RHSBO = dyn_cast<BinaryOperator>(RHSExpr); 8685 8686 // Check that one of the sides is a comparison operator. 8687 bool isLeftComp = LHSBO && LHSBO->isComparisonOp(); 8688 bool isRightComp = RHSBO && RHSBO->isComparisonOp(); 8689 if (!isLeftComp && !isRightComp) 8690 return; 8691 8692 // Bitwise operations are sometimes used as eager logical ops. 8693 // Don't diagnose this. 8694 bool isLeftBitwise = LHSBO && LHSBO->isBitwiseOp(); 8695 bool isRightBitwise = RHSBO && RHSBO->isBitwiseOp(); 8696 if ((isLeftComp || isLeftBitwise) && (isRightComp || isRightBitwise)) 8697 return; 8698 8699 SourceRange DiagRange = isLeftComp ? SourceRange(LHSExpr->getLocStart(), 8700 OpLoc) 8701 : SourceRange(OpLoc, RHSExpr->getLocEnd()); 8702 StringRef OpStr = isLeftComp ? LHSBO->getOpcodeStr() : RHSBO->getOpcodeStr(); 8703 SourceRange ParensRange = isLeftComp ? 8704 SourceRange(LHSBO->getRHS()->getLocStart(), RHSExpr->getLocEnd()) 8705 : SourceRange(LHSExpr->getLocStart(), RHSBO->getLHS()->getLocStart()); 8706 8707 Self.Diag(OpLoc, diag::warn_precedence_bitwise_rel) 8708 << DiagRange << BinaryOperator::getOpcodeStr(Opc) << OpStr; 8709 SuggestParentheses(Self, OpLoc, 8710 Self.PDiag(diag::note_precedence_silence) << OpStr, 8711 (isLeftComp ? LHSExpr : RHSExpr)->getSourceRange()); 8712 SuggestParentheses(Self, OpLoc, 8713 Self.PDiag(diag::note_precedence_bitwise_first) 8714 << BinaryOperator::getOpcodeStr(Opc), 8715 ParensRange); 8716} 8717 8718/// \brief It accepts a '&' expr that is inside a '|' one. 8719/// Emit a diagnostic together with a fixit hint that wraps the '&' expression 8720/// in parentheses. 8721static void 8722EmitDiagnosticForBitwiseAndInBitwiseOr(Sema &Self, SourceLocation OpLoc, 8723 BinaryOperator *Bop) { 8724 assert(Bop->getOpcode() == BO_And); 8725 Self.Diag(Bop->getOperatorLoc(), diag::warn_bitwise_and_in_bitwise_or) 8726 << Bop->getSourceRange() << OpLoc; 8727 SuggestParentheses(Self, Bop->getOperatorLoc(), 8728 Self.PDiag(diag::note_precedence_silence) 8729 << Bop->getOpcodeStr(), 8730 Bop->getSourceRange()); 8731} 8732 8733/// \brief It accepts a '&&' expr that is inside a '||' one. 8734/// Emit a diagnostic together with a fixit hint that wraps the '&&' expression 8735/// in parentheses. 8736static void 8737EmitDiagnosticForLogicalAndInLogicalOr(Sema &Self, SourceLocation OpLoc, 8738 BinaryOperator *Bop) { 8739 assert(Bop->getOpcode() == BO_LAnd); 8740 Self.Diag(Bop->getOperatorLoc(), diag::warn_logical_and_in_logical_or) 8741 << Bop->getSourceRange() << OpLoc; 8742 SuggestParentheses(Self, Bop->getOperatorLoc(), 8743 Self.PDiag(diag::note_precedence_silence) 8744 << Bop->getOpcodeStr(), 8745 Bop->getSourceRange()); 8746} 8747 8748/// \brief Returns true if the given expression can be evaluated as a constant 8749/// 'true'. 8750static bool EvaluatesAsTrue(Sema &S, Expr *E) { 8751 bool Res; 8752 return E->EvaluateAsBooleanCondition(Res, S.getASTContext()) && Res; 8753} 8754 8755/// \brief Returns true if the given expression can be evaluated as a constant 8756/// 'false'. 8757static bool EvaluatesAsFalse(Sema &S, Expr *E) { 8758 bool Res; 8759 return E->EvaluateAsBooleanCondition(Res, S.getASTContext()) && !Res; 8760} 8761 8762/// \brief Look for '&&' in the left hand of a '||' expr. 8763static void DiagnoseLogicalAndInLogicalOrLHS(Sema &S, SourceLocation OpLoc, 8764 Expr *LHSExpr, Expr *RHSExpr) { 8765 if (BinaryOperator *Bop = dyn_cast<BinaryOperator>(LHSExpr)) { 8766 if (Bop->getOpcode() == BO_LAnd) { 8767 // If it's "a && b || 0" don't warn since the precedence doesn't matter. 8768 if (EvaluatesAsFalse(S, RHSExpr)) 8769 return; 8770 // If it's "1 && a || b" don't warn since the precedence doesn't matter. 8771 if (!EvaluatesAsTrue(S, Bop->getLHS())) 8772 return EmitDiagnosticForLogicalAndInLogicalOr(S, OpLoc, Bop); 8773 } else if (Bop->getOpcode() == BO_LOr) { 8774 if (BinaryOperator *RBop = dyn_cast<BinaryOperator>(Bop->getRHS())) { 8775 // If it's "a || b && 1 || c" we didn't warn earlier for 8776 // "a || b && 1", but warn now. 8777 if (RBop->getOpcode() == BO_LAnd && EvaluatesAsTrue(S, RBop->getRHS())) 8778 return EmitDiagnosticForLogicalAndInLogicalOr(S, OpLoc, RBop); 8779 } 8780 } 8781 } 8782} 8783 8784/// \brief Look for '&&' in the right hand of a '||' expr. 8785static void DiagnoseLogicalAndInLogicalOrRHS(Sema &S, SourceLocation OpLoc, 8786 Expr *LHSExpr, Expr *RHSExpr) { 8787 if (BinaryOperator *Bop = dyn_cast<BinaryOperator>(RHSExpr)) { 8788 if (Bop->getOpcode() == BO_LAnd) { 8789 // If it's "0 || a && b" don't warn since the precedence doesn't matter. 8790 if (EvaluatesAsFalse(S, LHSExpr)) 8791 return; 8792 // If it's "a || b && 1" don't warn since the precedence doesn't matter. 8793 if (!EvaluatesAsTrue(S, Bop->getRHS())) 8794 return EmitDiagnosticForLogicalAndInLogicalOr(S, OpLoc, Bop); 8795 } 8796 } 8797} 8798 8799/// \brief Look for '&' in the left or right hand of a '|' expr. 8800static void DiagnoseBitwiseAndInBitwiseOr(Sema &S, SourceLocation OpLoc, 8801 Expr *OrArg) { 8802 if (BinaryOperator *Bop = dyn_cast<BinaryOperator>(OrArg)) { 8803 if (Bop->getOpcode() == BO_And) 8804 return EmitDiagnosticForBitwiseAndInBitwiseOr(S, OpLoc, Bop); 8805 } 8806} 8807 8808static void DiagnoseAdditionInShift(Sema &S, SourceLocation OpLoc, 8809 Expr *SubExpr, StringRef Shift) { 8810 if (BinaryOperator *Bop = dyn_cast<BinaryOperator>(SubExpr)) { 8811 if (Bop->getOpcode() == BO_Add || Bop->getOpcode() == BO_Sub) { 8812 StringRef Op = Bop->getOpcodeStr(); 8813 S.Diag(Bop->getOperatorLoc(), diag::warn_addition_in_bitshift) 8814 << Bop->getSourceRange() << OpLoc << Shift << Op; 8815 SuggestParentheses(S, Bop->getOperatorLoc(), 8816 S.PDiag(diag::note_precedence_silence) << Op, 8817 Bop->getSourceRange()); 8818 } 8819 } 8820} 8821 8822/// DiagnoseBinOpPrecedence - Emit warnings for expressions with tricky 8823/// precedence. 8824static void DiagnoseBinOpPrecedence(Sema &Self, BinaryOperatorKind Opc, 8825 SourceLocation OpLoc, Expr *LHSExpr, 8826 Expr *RHSExpr){ 8827 // Diagnose "arg1 'bitwise' arg2 'eq' arg3". 8828 if (BinaryOperator::isBitwiseOp(Opc)) 8829 DiagnoseBitwisePrecedence(Self, Opc, OpLoc, LHSExpr, RHSExpr); 8830 8831 // Diagnose "arg1 & arg2 | arg3" 8832 if (Opc == BO_Or && !OpLoc.isMacroID()/* Don't warn in macros. */) { 8833 DiagnoseBitwiseAndInBitwiseOr(Self, OpLoc, LHSExpr); 8834 DiagnoseBitwiseAndInBitwiseOr(Self, OpLoc, RHSExpr); 8835 } 8836 8837 // Warn about arg1 || arg2 && arg3, as GCC 4.3+ does. 8838 // We don't warn for 'assert(a || b && "bad")' since this is safe. 8839 if (Opc == BO_LOr && !OpLoc.isMacroID()/* Don't warn in macros. */) { 8840 DiagnoseLogicalAndInLogicalOrLHS(Self, OpLoc, LHSExpr, RHSExpr); 8841 DiagnoseLogicalAndInLogicalOrRHS(Self, OpLoc, LHSExpr, RHSExpr); 8842 } 8843 8844 if ((Opc == BO_Shl && LHSExpr->getType()->isIntegralType(Self.getASTContext())) 8845 || Opc == BO_Shr) { 8846 StringRef Shift = BinaryOperator::getOpcodeStr(Opc); 8847 DiagnoseAdditionInShift(Self, OpLoc, LHSExpr, Shift); 8848 DiagnoseAdditionInShift(Self, OpLoc, RHSExpr, Shift); 8849 } 8850} 8851 8852// Binary Operators. 'Tok' is the token for the operator. 8853ExprResult Sema::ActOnBinOp(Scope *S, SourceLocation TokLoc, 8854 tok::TokenKind Kind, 8855 Expr *LHSExpr, Expr *RHSExpr) { 8856 BinaryOperatorKind Opc = ConvertTokenKindToBinaryOpcode(Kind); 8857 assert((LHSExpr != 0) && "ActOnBinOp(): missing left expression"); 8858 assert((RHSExpr != 0) && "ActOnBinOp(): missing right expression"); 8859 8860 // Emit warnings for tricky precedence issues, e.g. "bitfield & 0x4 == 0" 8861 DiagnoseBinOpPrecedence(*this, Opc, TokLoc, LHSExpr, RHSExpr); 8862 8863 return BuildBinOp(S, TokLoc, Opc, LHSExpr, RHSExpr); 8864} 8865 8866/// Build an overloaded binary operator expression in the given scope. 8867static ExprResult BuildOverloadedBinOp(Sema &S, Scope *Sc, SourceLocation OpLoc, 8868 BinaryOperatorKind Opc, 8869 Expr *LHS, Expr *RHS) { 8870 // Find all of the overloaded operators visible from this 8871 // point. We perform both an operator-name lookup from the local 8872 // scope and an argument-dependent lookup based on the types of 8873 // the arguments. 8874 UnresolvedSet<16> Functions; 8875 OverloadedOperatorKind OverOp 8876 = BinaryOperator::getOverloadedOperator(Opc); 8877 if (Sc && OverOp != OO_None) 8878 S.LookupOverloadedOperatorName(OverOp, Sc, LHS->getType(), 8879 RHS->getType(), Functions); 8880 8881 // Build the (potentially-overloaded, potentially-dependent) 8882 // binary operation. 8883 return S.CreateOverloadedBinOp(OpLoc, Opc, Functions, LHS, RHS); 8884} 8885 8886ExprResult Sema::BuildBinOp(Scope *S, SourceLocation OpLoc, 8887 BinaryOperatorKind Opc, 8888 Expr *LHSExpr, Expr *RHSExpr) { 8889 // We want to end up calling one of checkPseudoObjectAssignment 8890 // (if the LHS is a pseudo-object), BuildOverloadedBinOp (if 8891 // both expressions are overloadable or either is type-dependent), 8892 // or CreateBuiltinBinOp (in any other case). We also want to get 8893 // any placeholder types out of the way. 8894 8895 // Handle pseudo-objects in the LHS. 8896 if (const BuiltinType *pty = LHSExpr->getType()->getAsPlaceholderType()) { 8897 // Assignments with a pseudo-object l-value need special analysis. 8898 if (pty->getKind() == BuiltinType::PseudoObject && 8899 BinaryOperator::isAssignmentOp(Opc)) 8900 return checkPseudoObjectAssignment(S, OpLoc, Opc, LHSExpr, RHSExpr); 8901 8902 // Don't resolve overloads if the other type is overloadable. 8903 if (pty->getKind() == BuiltinType::Overload) { 8904 // We can't actually test that if we still have a placeholder, 8905 // though. Fortunately, none of the exceptions we see in that 8906 // code below are valid when the LHS is an overload set. Note 8907 // that an overload set can be dependently-typed, but it never 8908 // instantiates to having an overloadable type. 8909 ExprResult resolvedRHS = CheckPlaceholderExpr(RHSExpr); 8910 if (resolvedRHS.isInvalid()) return ExprError(); 8911 RHSExpr = resolvedRHS.take(); 8912 8913 if (RHSExpr->isTypeDependent() || 8914 RHSExpr->getType()->isOverloadableType()) 8915 return BuildOverloadedBinOp(*this, S, OpLoc, Opc, LHSExpr, RHSExpr); 8916 } 8917 8918 ExprResult LHS = CheckPlaceholderExpr(LHSExpr); 8919 if (LHS.isInvalid()) return ExprError(); 8920 LHSExpr = LHS.take(); 8921 } 8922 8923 // Handle pseudo-objects in the RHS. 8924 if (const BuiltinType *pty = RHSExpr->getType()->getAsPlaceholderType()) { 8925 // An overload in the RHS can potentially be resolved by the type 8926 // being assigned to. 8927 if (Opc == BO_Assign && pty->getKind() == BuiltinType::Overload) { 8928 if (LHSExpr->isTypeDependent() || RHSExpr->isTypeDependent()) 8929 return BuildOverloadedBinOp(*this, S, OpLoc, Opc, LHSExpr, RHSExpr); 8930 8931 if (LHSExpr->getType()->isOverloadableType()) 8932 return BuildOverloadedBinOp(*this, S, OpLoc, Opc, LHSExpr, RHSExpr); 8933 8934 return CreateBuiltinBinOp(OpLoc, Opc, LHSExpr, RHSExpr); 8935 } 8936 8937 // Don't resolve overloads if the other type is overloadable. 8938 if (pty->getKind() == BuiltinType::Overload && 8939 LHSExpr->getType()->isOverloadableType()) 8940 return BuildOverloadedBinOp(*this, S, OpLoc, Opc, LHSExpr, RHSExpr); 8941 8942 ExprResult resolvedRHS = CheckPlaceholderExpr(RHSExpr); 8943 if (!resolvedRHS.isUsable()) return ExprError(); 8944 RHSExpr = resolvedRHS.take(); 8945 } 8946 8947 if (getLangOpts().CPlusPlus) { 8948 // If either expression is type-dependent, always build an 8949 // overloaded op. 8950 if (LHSExpr->isTypeDependent() || RHSExpr->isTypeDependent()) 8951 return BuildOverloadedBinOp(*this, S, OpLoc, Opc, LHSExpr, RHSExpr); 8952 8953 // Otherwise, build an overloaded op if either expression has an 8954 // overloadable type. 8955 if (LHSExpr->getType()->isOverloadableType() || 8956 RHSExpr->getType()->isOverloadableType()) 8957 return BuildOverloadedBinOp(*this, S, OpLoc, Opc, LHSExpr, RHSExpr); 8958 } 8959 8960 // Build a built-in binary operation. 8961 return CreateBuiltinBinOp(OpLoc, Opc, LHSExpr, RHSExpr); 8962} 8963 8964ExprResult Sema::CreateBuiltinUnaryOp(SourceLocation OpLoc, 8965 UnaryOperatorKind Opc, 8966 Expr *InputExpr) { 8967 ExprResult Input = Owned(InputExpr); 8968 ExprValueKind VK = VK_RValue; 8969 ExprObjectKind OK = OK_Ordinary; 8970 QualType resultType; 8971 switch (Opc) { 8972 case UO_PreInc: 8973 case UO_PreDec: 8974 case UO_PostInc: 8975 case UO_PostDec: 8976 resultType = CheckIncrementDecrementOperand(*this, Input.get(), VK, OpLoc, 8977 Opc == UO_PreInc || 8978 Opc == UO_PostInc, 8979 Opc == UO_PreInc || 8980 Opc == UO_PreDec); 8981 break; 8982 case UO_AddrOf: 8983 resultType = CheckAddressOfOperand(*this, Input, OpLoc); 8984 break; 8985 case UO_Deref: { 8986 Input = DefaultFunctionArrayLvalueConversion(Input.take()); 8987 if (Input.isInvalid()) return ExprError(); 8988 resultType = CheckIndirectionOperand(*this, Input.get(), VK, OpLoc); 8989 break; 8990 } 8991 case UO_Plus: 8992 case UO_Minus: 8993 Input = UsualUnaryConversions(Input.take()); 8994 if (Input.isInvalid()) return ExprError(); 8995 resultType = Input.get()->getType(); 8996 if (resultType->isDependentType()) 8997 break; 8998 if (resultType->isArithmeticType() || // C99 6.5.3.3p1 8999 resultType->isVectorType()) 9000 break; 9001 else if (getLangOpts().CPlusPlus && // C++ [expr.unary.op]p6-7 9002 resultType->isEnumeralType()) 9003 break; 9004 else if (getLangOpts().CPlusPlus && // C++ [expr.unary.op]p6 9005 Opc == UO_Plus && 9006 resultType->isPointerType()) 9007 break; 9008 9009 return ExprError(Diag(OpLoc, diag::err_typecheck_unary_expr) 9010 << resultType << Input.get()->getSourceRange()); 9011 9012 case UO_Not: // bitwise complement 9013 Input = UsualUnaryConversions(Input.take()); 9014 if (Input.isInvalid()) 9015 return ExprError(); 9016 resultType = Input.get()->getType(); 9017 if (resultType->isDependentType()) 9018 break; 9019 // C99 6.5.3.3p1. We allow complex int and float as a GCC extension. 9020 if (resultType->isComplexType() || resultType->isComplexIntegerType()) 9021 // C99 does not support '~' for complex conjugation. 9022 Diag(OpLoc, diag::ext_integer_complement_complex) 9023 << resultType << Input.get()->getSourceRange(); 9024 else if (resultType->hasIntegerRepresentation()) 9025 break; 9026 else if (resultType->isExtVectorType()) { 9027 if (Context.getLangOpts().OpenCL) { 9028 // OpenCL v1.1 s6.3.f: The bitwise operator not (~) does not operate 9029 // on vector float types. 9030 QualType T = resultType->getAs<ExtVectorType>()->getElementType(); 9031 if (!T->isIntegerType()) 9032 return ExprError(Diag(OpLoc, diag::err_typecheck_unary_expr) 9033 << resultType << Input.get()->getSourceRange()); 9034 } 9035 break; 9036 } else { 9037 return ExprError(Diag(OpLoc, diag::err_typecheck_unary_expr) 9038 << resultType << Input.get()->getSourceRange()); 9039 } 9040 break; 9041 9042 case UO_LNot: // logical negation 9043 // Unlike +/-/~, integer promotions aren't done here (C99 6.5.3.3p5). 9044 Input = DefaultFunctionArrayLvalueConversion(Input.take()); 9045 if (Input.isInvalid()) return ExprError(); 9046 resultType = Input.get()->getType(); 9047 9048 // Though we still have to promote half FP to float... 9049 if (resultType->isHalfType() && !Context.getLangOpts().NativeHalfType) { 9050 Input = ImpCastExprToType(Input.take(), Context.FloatTy, CK_FloatingCast).take(); 9051 resultType = Context.FloatTy; 9052 } 9053 9054 if (resultType->isDependentType()) 9055 break; 9056 if (resultType->isScalarType()) { 9057 // C99 6.5.3.3p1: ok, fallthrough; 9058 if (Context.getLangOpts().CPlusPlus) { 9059 // C++03 [expr.unary.op]p8, C++0x [expr.unary.op]p9: 9060 // operand contextually converted to bool. 9061 Input = ImpCastExprToType(Input.take(), Context.BoolTy, 9062 ScalarTypeToBooleanCastKind(resultType)); 9063 } else if (Context.getLangOpts().OpenCL && 9064 Context.getLangOpts().OpenCLVersion < 120) { 9065 // OpenCL v1.1 6.3.h: The logical operator not (!) does not 9066 // operate on scalar float types. 9067 if (!resultType->isIntegerType()) 9068 return ExprError(Diag(OpLoc, diag::err_typecheck_unary_expr) 9069 << resultType << Input.get()->getSourceRange()); 9070 } 9071 } else if (resultType->isExtVectorType()) { 9072 if (Context.getLangOpts().OpenCL && 9073 Context.getLangOpts().OpenCLVersion < 120) { 9074 // OpenCL v1.1 6.3.h: The logical operator not (!) does not 9075 // operate on vector float types. 9076 QualType T = resultType->getAs<ExtVectorType>()->getElementType(); 9077 if (!T->isIntegerType()) 9078 return ExprError(Diag(OpLoc, diag::err_typecheck_unary_expr) 9079 << resultType << Input.get()->getSourceRange()); 9080 } 9081 // Vector logical not returns the signed variant of the operand type. 9082 resultType = GetSignedVectorType(resultType); 9083 break; 9084 } else { 9085 return ExprError(Diag(OpLoc, diag::err_typecheck_unary_expr) 9086 << resultType << Input.get()->getSourceRange()); 9087 } 9088 9089 // LNot always has type int. C99 6.5.3.3p5. 9090 // In C++, it's bool. C++ 5.3.1p8 9091 resultType = Context.getLogicalOperationType(); 9092 break; 9093 case UO_Real: 9094 case UO_Imag: 9095 resultType = CheckRealImagOperand(*this, Input, OpLoc, Opc == UO_Real); 9096 // _Real maps ordinary l-values into ordinary l-values. _Imag maps ordinary 9097 // complex l-values to ordinary l-values and all other values to r-values. 9098 if (Input.isInvalid()) return ExprError(); 9099 if (Opc == UO_Real || Input.get()->getType()->isAnyComplexType()) { 9100 if (Input.get()->getValueKind() != VK_RValue && 9101 Input.get()->getObjectKind() == OK_Ordinary) 9102 VK = Input.get()->getValueKind(); 9103 } else if (!getLangOpts().CPlusPlus) { 9104 // In C, a volatile scalar is read by __imag. In C++, it is not. 9105 Input = DefaultLvalueConversion(Input.take()); 9106 } 9107 break; 9108 case UO_Extension: 9109 resultType = Input.get()->getType(); 9110 VK = Input.get()->getValueKind(); 9111 OK = Input.get()->getObjectKind(); 9112 break; 9113 } 9114 if (resultType.isNull() || Input.isInvalid()) 9115 return ExprError(); 9116 9117 // Check for array bounds violations in the operand of the UnaryOperator, 9118 // except for the '*' and '&' operators that have to be handled specially 9119 // by CheckArrayAccess (as there are special cases like &array[arraysize] 9120 // that are explicitly defined as valid by the standard). 9121 if (Opc != UO_AddrOf && Opc != UO_Deref) 9122 CheckArrayAccess(Input.get()); 9123 9124 return Owned(new (Context) UnaryOperator(Input.take(), Opc, resultType, 9125 VK, OK, OpLoc)); 9126} 9127 9128/// \brief Determine whether the given expression is a qualified member 9129/// access expression, of a form that could be turned into a pointer to member 9130/// with the address-of operator. 9131static bool isQualifiedMemberAccess(Expr *E) { 9132 if (DeclRefExpr *DRE = dyn_cast<DeclRefExpr>(E)) { 9133 if (!DRE->getQualifier()) 9134 return false; 9135 9136 ValueDecl *VD = DRE->getDecl(); 9137 if (!VD->isCXXClassMember()) 9138 return false; 9139 9140 if (isa<FieldDecl>(VD) || isa<IndirectFieldDecl>(VD)) 9141 return true; 9142 if (CXXMethodDecl *Method = dyn_cast<CXXMethodDecl>(VD)) 9143 return Method->isInstance(); 9144 9145 return false; 9146 } 9147 9148 if (UnresolvedLookupExpr *ULE = dyn_cast<UnresolvedLookupExpr>(E)) { 9149 if (!ULE->getQualifier()) 9150 return false; 9151 9152 for (UnresolvedLookupExpr::decls_iterator D = ULE->decls_begin(), 9153 DEnd = ULE->decls_end(); 9154 D != DEnd; ++D) { 9155 if (CXXMethodDecl *Method = dyn_cast<CXXMethodDecl>(*D)) { 9156 if (Method->isInstance()) 9157 return true; 9158 } else { 9159 // Overload set does not contain methods. 9160 break; 9161 } 9162 } 9163 9164 return false; 9165 } 9166 9167 return false; 9168} 9169 9170ExprResult Sema::BuildUnaryOp(Scope *S, SourceLocation OpLoc, 9171 UnaryOperatorKind Opc, Expr *Input) { 9172 // First things first: handle placeholders so that the 9173 // overloaded-operator check considers the right type. 9174 if (const BuiltinType *pty = Input->getType()->getAsPlaceholderType()) { 9175 // Increment and decrement of pseudo-object references. 9176 if (pty->getKind() == BuiltinType::PseudoObject && 9177 UnaryOperator::isIncrementDecrementOp(Opc)) 9178 return checkPseudoObjectIncDec(S, OpLoc, Opc, Input); 9179 9180 // extension is always a builtin operator. 9181 if (Opc == UO_Extension) 9182 return CreateBuiltinUnaryOp(OpLoc, Opc, Input); 9183 9184 // & gets special logic for several kinds of placeholder. 9185 // The builtin code knows what to do. 9186 if (Opc == UO_AddrOf && 9187 (pty->getKind() == BuiltinType::Overload || 9188 pty->getKind() == BuiltinType::UnknownAny || 9189 pty->getKind() == BuiltinType::BoundMember)) 9190 return CreateBuiltinUnaryOp(OpLoc, Opc, Input); 9191 9192 // Anything else needs to be handled now. 9193 ExprResult Result = CheckPlaceholderExpr(Input); 9194 if (Result.isInvalid()) return ExprError(); 9195 Input = Result.take(); 9196 } 9197 9198 if (getLangOpts().CPlusPlus && Input->getType()->isOverloadableType() && 9199 UnaryOperator::getOverloadedOperator(Opc) != OO_None && 9200 !(Opc == UO_AddrOf && isQualifiedMemberAccess(Input))) { 9201 // Find all of the overloaded operators visible from this 9202 // point. We perform both an operator-name lookup from the local 9203 // scope and an argument-dependent lookup based on the types of 9204 // the arguments. 9205 UnresolvedSet<16> Functions; 9206 OverloadedOperatorKind OverOp = UnaryOperator::getOverloadedOperator(Opc); 9207 if (S && OverOp != OO_None) 9208 LookupOverloadedOperatorName(OverOp, S, Input->getType(), QualType(), 9209 Functions); 9210 9211 return CreateOverloadedUnaryOp(OpLoc, Opc, Functions, Input); 9212 } 9213 9214 return CreateBuiltinUnaryOp(OpLoc, Opc, Input); 9215} 9216 9217// Unary Operators. 'Tok' is the token for the operator. 9218ExprResult Sema::ActOnUnaryOp(Scope *S, SourceLocation OpLoc, 9219 tok::TokenKind Op, Expr *Input) { 9220 return BuildUnaryOp(S, OpLoc, ConvertTokenKindToUnaryOpcode(Op), Input); 9221} 9222 9223/// ActOnAddrLabel - Parse the GNU address of label extension: "&&foo". 9224ExprResult Sema::ActOnAddrLabel(SourceLocation OpLoc, SourceLocation LabLoc, 9225 LabelDecl *TheDecl) { 9226 TheDecl->setUsed(); 9227 // Create the AST node. The address of a label always has type 'void*'. 9228 return Owned(new (Context) AddrLabelExpr(OpLoc, LabLoc, TheDecl, 9229 Context.getPointerType(Context.VoidTy))); 9230} 9231 9232/// Given the last statement in a statement-expression, check whether 9233/// the result is a producing expression (like a call to an 9234/// ns_returns_retained function) and, if so, rebuild it to hoist the 9235/// release out of the full-expression. Otherwise, return null. 9236/// Cannot fail. 9237static Expr *maybeRebuildARCConsumingStmt(Stmt *Statement) { 9238 // Should always be wrapped with one of these. 9239 ExprWithCleanups *cleanups = dyn_cast<ExprWithCleanups>(Statement); 9240 if (!cleanups) return 0; 9241 9242 ImplicitCastExpr *cast = dyn_cast<ImplicitCastExpr>(cleanups->getSubExpr()); 9243 if (!cast || cast->getCastKind() != CK_ARCConsumeObject) 9244 return 0; 9245 9246 // Splice out the cast. This shouldn't modify any interesting 9247 // features of the statement. 9248 Expr *producer = cast->getSubExpr(); 9249 assert(producer->getType() == cast->getType()); 9250 assert(producer->getValueKind() == cast->getValueKind()); 9251 cleanups->setSubExpr(producer); 9252 return cleanups; 9253} 9254 9255void Sema::ActOnStartStmtExpr() { 9256 PushExpressionEvaluationContext(ExprEvalContexts.back().Context); 9257} 9258 9259void Sema::ActOnStmtExprError() { 9260 // Note that function is also called by TreeTransform when leaving a 9261 // StmtExpr scope without rebuilding anything. 9262 9263 DiscardCleanupsInEvaluationContext(); 9264 PopExpressionEvaluationContext(); 9265} 9266 9267ExprResult 9268Sema::ActOnStmtExpr(SourceLocation LPLoc, Stmt *SubStmt, 9269 SourceLocation RPLoc) { // "({..})" 9270 assert(SubStmt && isa<CompoundStmt>(SubStmt) && "Invalid action invocation!"); 9271 CompoundStmt *Compound = cast<CompoundStmt>(SubStmt); 9272 9273 if (hasAnyUnrecoverableErrorsInThisFunction()) 9274 DiscardCleanupsInEvaluationContext(); 9275 assert(!ExprNeedsCleanups && "cleanups within StmtExpr not correctly bound!"); 9276 PopExpressionEvaluationContext(); 9277 9278 bool isFileScope 9279 = (getCurFunctionOrMethodDecl() == 0) && (getCurBlock() == 0); 9280 if (isFileScope) 9281 return ExprError(Diag(LPLoc, diag::err_stmtexpr_file_scope)); 9282 9283 // FIXME: there are a variety of strange constraints to enforce here, for 9284 // example, it is not possible to goto into a stmt expression apparently. 9285 // More semantic analysis is needed. 9286 9287 // If there are sub stmts in the compound stmt, take the type of the last one 9288 // as the type of the stmtexpr. 9289 QualType Ty = Context.VoidTy; 9290 bool StmtExprMayBindToTemp = false; 9291 if (!Compound->body_empty()) { 9292 Stmt *LastStmt = Compound->body_back(); 9293 LabelStmt *LastLabelStmt = 0; 9294 // If LastStmt is a label, skip down through into the body. 9295 while (LabelStmt *Label = dyn_cast<LabelStmt>(LastStmt)) { 9296 LastLabelStmt = Label; 9297 LastStmt = Label->getSubStmt(); 9298 } 9299 9300 if (Expr *LastE = dyn_cast<Expr>(LastStmt)) { 9301 // Do function/array conversion on the last expression, but not 9302 // lvalue-to-rvalue. However, initialize an unqualified type. 9303 ExprResult LastExpr = DefaultFunctionArrayConversion(LastE); 9304 if (LastExpr.isInvalid()) 9305 return ExprError(); 9306 Ty = LastExpr.get()->getType().getUnqualifiedType(); 9307 9308 if (!Ty->isDependentType() && !LastExpr.get()->isTypeDependent()) { 9309 // In ARC, if the final expression ends in a consume, splice 9310 // the consume out and bind it later. In the alternate case 9311 // (when dealing with a retainable type), the result 9312 // initialization will create a produce. In both cases the 9313 // result will be +1, and we'll need to balance that out with 9314 // a bind. 9315 if (Expr *rebuiltLastStmt 9316 = maybeRebuildARCConsumingStmt(LastExpr.get())) { 9317 LastExpr = rebuiltLastStmt; 9318 } else { 9319 LastExpr = PerformCopyInitialization( 9320 InitializedEntity::InitializeResult(LPLoc, 9321 Ty, 9322 false), 9323 SourceLocation(), 9324 LastExpr); 9325 } 9326 9327 if (LastExpr.isInvalid()) 9328 return ExprError(); 9329 if (LastExpr.get() != 0) { 9330 if (!LastLabelStmt) 9331 Compound->setLastStmt(LastExpr.take()); 9332 else 9333 LastLabelStmt->setSubStmt(LastExpr.take()); 9334 StmtExprMayBindToTemp = true; 9335 } 9336 } 9337 } 9338 } 9339 9340 // FIXME: Check that expression type is complete/non-abstract; statement 9341 // expressions are not lvalues. 9342 Expr *ResStmtExpr = new (Context) StmtExpr(Compound, Ty, LPLoc, RPLoc); 9343 if (StmtExprMayBindToTemp) 9344 return MaybeBindToTemporary(ResStmtExpr); 9345 return Owned(ResStmtExpr); 9346} 9347 9348ExprResult Sema::BuildBuiltinOffsetOf(SourceLocation BuiltinLoc, 9349 TypeSourceInfo *TInfo, 9350 OffsetOfComponent *CompPtr, 9351 unsigned NumComponents, 9352 SourceLocation RParenLoc) { 9353 QualType ArgTy = TInfo->getType(); 9354 bool Dependent = ArgTy->isDependentType(); 9355 SourceRange TypeRange = TInfo->getTypeLoc().getLocalSourceRange(); 9356 9357 // We must have at least one component that refers to the type, and the first 9358 // one is known to be a field designator. Verify that the ArgTy represents 9359 // a struct/union/class. 9360 if (!Dependent && !ArgTy->isRecordType()) 9361 return ExprError(Diag(BuiltinLoc, diag::err_offsetof_record_type) 9362 << ArgTy << TypeRange); 9363 9364 // Type must be complete per C99 7.17p3 because a declaring a variable 9365 // with an incomplete type would be ill-formed. 9366 if (!Dependent 9367 && RequireCompleteType(BuiltinLoc, ArgTy, 9368 diag::err_offsetof_incomplete_type, TypeRange)) 9369 return ExprError(); 9370 9371 // offsetof with non-identifier designators (e.g. "offsetof(x, a.b[c])") are a 9372 // GCC extension, diagnose them. 9373 // FIXME: This diagnostic isn't actually visible because the location is in 9374 // a system header! 9375 if (NumComponents != 1) 9376 Diag(BuiltinLoc, diag::ext_offsetof_extended_field_designator) 9377 << SourceRange(CompPtr[1].LocStart, CompPtr[NumComponents-1].LocEnd); 9378 9379 bool DidWarnAboutNonPOD = false; 9380 QualType CurrentType = ArgTy; 9381 typedef OffsetOfExpr::OffsetOfNode OffsetOfNode; 9382 SmallVector<OffsetOfNode, 4> Comps; 9383 SmallVector<Expr*, 4> Exprs; 9384 for (unsigned i = 0; i != NumComponents; ++i) { 9385 const OffsetOfComponent &OC = CompPtr[i]; 9386 if (OC.isBrackets) { 9387 // Offset of an array sub-field. TODO: Should we allow vector elements? 9388 if (!CurrentType->isDependentType()) { 9389 const ArrayType *AT = Context.getAsArrayType(CurrentType); 9390 if(!AT) 9391 return ExprError(Diag(OC.LocEnd, diag::err_offsetof_array_type) 9392 << CurrentType); 9393 CurrentType = AT->getElementType(); 9394 } else 9395 CurrentType = Context.DependentTy; 9396 9397 ExprResult IdxRval = DefaultLvalueConversion(static_cast<Expr*>(OC.U.E)); 9398 if (IdxRval.isInvalid()) 9399 return ExprError(); 9400 Expr *Idx = IdxRval.take(); 9401 9402 // The expression must be an integral expression. 9403 // FIXME: An integral constant expression? 9404 if (!Idx->isTypeDependent() && !Idx->isValueDependent() && 9405 !Idx->getType()->isIntegerType()) 9406 return ExprError(Diag(Idx->getLocStart(), 9407 diag::err_typecheck_subscript_not_integer) 9408 << Idx->getSourceRange()); 9409 9410 // Record this array index. 9411 Comps.push_back(OffsetOfNode(OC.LocStart, Exprs.size(), OC.LocEnd)); 9412 Exprs.push_back(Idx); 9413 continue; 9414 } 9415 9416 // Offset of a field. 9417 if (CurrentType->isDependentType()) { 9418 // We have the offset of a field, but we can't look into the dependent 9419 // type. Just record the identifier of the field. 9420 Comps.push_back(OffsetOfNode(OC.LocStart, OC.U.IdentInfo, OC.LocEnd)); 9421 CurrentType = Context.DependentTy; 9422 continue; 9423 } 9424 9425 // We need to have a complete type to look into. 9426 if (RequireCompleteType(OC.LocStart, CurrentType, 9427 diag::err_offsetof_incomplete_type)) 9428 return ExprError(); 9429 9430 // Look for the designated field. 9431 const RecordType *RC = CurrentType->getAs<RecordType>(); 9432 if (!RC) 9433 return ExprError(Diag(OC.LocEnd, diag::err_offsetof_record_type) 9434 << CurrentType); 9435 RecordDecl *RD = RC->getDecl(); 9436 9437 // C++ [lib.support.types]p5: 9438 // The macro offsetof accepts a restricted set of type arguments in this 9439 // International Standard. type shall be a POD structure or a POD union 9440 // (clause 9). 9441 // C++11 [support.types]p4: 9442 // If type is not a standard-layout class (Clause 9), the results are 9443 // undefined. 9444 if (CXXRecordDecl *CRD = dyn_cast<CXXRecordDecl>(RD)) { 9445 bool IsSafe = LangOpts.CPlusPlus11? CRD->isStandardLayout() : CRD->isPOD(); 9446 unsigned DiagID = 9447 LangOpts.CPlusPlus11? diag::warn_offsetof_non_standardlayout_type 9448 : diag::warn_offsetof_non_pod_type; 9449 9450 if (!IsSafe && !DidWarnAboutNonPOD && 9451 DiagRuntimeBehavior(BuiltinLoc, 0, 9452 PDiag(DiagID) 9453 << SourceRange(CompPtr[0].LocStart, OC.LocEnd) 9454 << CurrentType)) 9455 DidWarnAboutNonPOD = true; 9456 } 9457 9458 // Look for the field. 9459 LookupResult R(*this, OC.U.IdentInfo, OC.LocStart, LookupMemberName); 9460 LookupQualifiedName(R, RD); 9461 FieldDecl *MemberDecl = R.getAsSingle<FieldDecl>(); 9462 IndirectFieldDecl *IndirectMemberDecl = 0; 9463 if (!MemberDecl) { 9464 if ((IndirectMemberDecl = R.getAsSingle<IndirectFieldDecl>())) 9465 MemberDecl = IndirectMemberDecl->getAnonField(); 9466 } 9467 9468 if (!MemberDecl) 9469 return ExprError(Diag(BuiltinLoc, diag::err_no_member) 9470 << OC.U.IdentInfo << RD << SourceRange(OC.LocStart, 9471 OC.LocEnd)); 9472 9473 // C99 7.17p3: 9474 // (If the specified member is a bit-field, the behavior is undefined.) 9475 // 9476 // We diagnose this as an error. 9477 if (MemberDecl->isBitField()) { 9478 Diag(OC.LocEnd, diag::err_offsetof_bitfield) 9479 << MemberDecl->getDeclName() 9480 << SourceRange(BuiltinLoc, RParenLoc); 9481 Diag(MemberDecl->getLocation(), diag::note_bitfield_decl); 9482 return ExprError(); 9483 } 9484 9485 RecordDecl *Parent = MemberDecl->getParent(); 9486 if (IndirectMemberDecl) 9487 Parent = cast<RecordDecl>(IndirectMemberDecl->getDeclContext()); 9488 9489 // If the member was found in a base class, introduce OffsetOfNodes for 9490 // the base class indirections. 9491 CXXBasePaths Paths(/*FindAmbiguities=*/true, /*RecordPaths=*/true, 9492 /*DetectVirtual=*/false); 9493 if (IsDerivedFrom(CurrentType, Context.getTypeDeclType(Parent), Paths)) { 9494 CXXBasePath &Path = Paths.front(); 9495 for (CXXBasePath::iterator B = Path.begin(), BEnd = Path.end(); 9496 B != BEnd; ++B) 9497 Comps.push_back(OffsetOfNode(B->Base)); 9498 } 9499 9500 if (IndirectMemberDecl) { 9501 for (IndirectFieldDecl::chain_iterator FI = 9502 IndirectMemberDecl->chain_begin(), 9503 FEnd = IndirectMemberDecl->chain_end(); FI != FEnd; FI++) { 9504 assert(isa<FieldDecl>(*FI)); 9505 Comps.push_back(OffsetOfNode(OC.LocStart, 9506 cast<FieldDecl>(*FI), OC.LocEnd)); 9507 } 9508 } else 9509 Comps.push_back(OffsetOfNode(OC.LocStart, MemberDecl, OC.LocEnd)); 9510 9511 CurrentType = MemberDecl->getType().getNonReferenceType(); 9512 } 9513 9514 return Owned(OffsetOfExpr::Create(Context, Context.getSizeType(), BuiltinLoc, 9515 TInfo, Comps, Exprs, RParenLoc)); 9516} 9517 9518ExprResult Sema::ActOnBuiltinOffsetOf(Scope *S, 9519 SourceLocation BuiltinLoc, 9520 SourceLocation TypeLoc, 9521 ParsedType ParsedArgTy, 9522 OffsetOfComponent *CompPtr, 9523 unsigned NumComponents, 9524 SourceLocation RParenLoc) { 9525 9526 TypeSourceInfo *ArgTInfo; 9527 QualType ArgTy = GetTypeFromParser(ParsedArgTy, &ArgTInfo); 9528 if (ArgTy.isNull()) 9529 return ExprError(); 9530 9531 if (!ArgTInfo) 9532 ArgTInfo = Context.getTrivialTypeSourceInfo(ArgTy, TypeLoc); 9533 9534 return BuildBuiltinOffsetOf(BuiltinLoc, ArgTInfo, CompPtr, NumComponents, 9535 RParenLoc); 9536} 9537 9538 9539ExprResult Sema::ActOnChooseExpr(SourceLocation BuiltinLoc, 9540 Expr *CondExpr, 9541 Expr *LHSExpr, Expr *RHSExpr, 9542 SourceLocation RPLoc) { 9543 assert((CondExpr && LHSExpr && RHSExpr) && "Missing type argument(s)"); 9544 9545 ExprValueKind VK = VK_RValue; 9546 ExprObjectKind OK = OK_Ordinary; 9547 QualType resType; 9548 bool ValueDependent = false; 9549 if (CondExpr->isTypeDependent() || CondExpr->isValueDependent()) { 9550 resType = Context.DependentTy; 9551 ValueDependent = true; 9552 } else { 9553 // The conditional expression is required to be a constant expression. 9554 llvm::APSInt condEval(32); 9555 ExprResult CondICE 9556 = VerifyIntegerConstantExpression(CondExpr, &condEval, 9557 diag::err_typecheck_choose_expr_requires_constant, false); 9558 if (CondICE.isInvalid()) 9559 return ExprError(); 9560 CondExpr = CondICE.take(); 9561 9562 // If the condition is > zero, then the AST type is the same as the LSHExpr. 9563 Expr *ActiveExpr = condEval.getZExtValue() ? LHSExpr : RHSExpr; 9564 9565 resType = ActiveExpr->getType(); 9566 ValueDependent = ActiveExpr->isValueDependent(); 9567 VK = ActiveExpr->getValueKind(); 9568 OK = ActiveExpr->getObjectKind(); 9569 } 9570 9571 return Owned(new (Context) ChooseExpr(BuiltinLoc, CondExpr, LHSExpr, RHSExpr, 9572 resType, VK, OK, RPLoc, 9573 resType->isDependentType(), 9574 ValueDependent)); 9575} 9576 9577//===----------------------------------------------------------------------===// 9578// Clang Extensions. 9579//===----------------------------------------------------------------------===// 9580 9581/// ActOnBlockStart - This callback is invoked when a block literal is started. 9582void Sema::ActOnBlockStart(SourceLocation CaretLoc, Scope *CurScope) { 9583 BlockDecl *Block = BlockDecl::Create(Context, CurContext, CaretLoc); 9584 PushBlockScope(CurScope, Block); 9585 CurContext->addDecl(Block); 9586 if (CurScope) 9587 PushDeclContext(CurScope, Block); 9588 else 9589 CurContext = Block; 9590 9591 getCurBlock()->HasImplicitReturnType = true; 9592 9593 // Enter a new evaluation context to insulate the block from any 9594 // cleanups from the enclosing full-expression. 9595 PushExpressionEvaluationContext(PotentiallyEvaluated); 9596} 9597 9598void Sema::ActOnBlockArguments(SourceLocation CaretLoc, Declarator &ParamInfo, 9599 Scope *CurScope) { 9600 assert(ParamInfo.getIdentifier()==0 && "block-id should have no identifier!"); 9601 assert(ParamInfo.getContext() == Declarator::BlockLiteralContext); 9602 BlockScopeInfo *CurBlock = getCurBlock(); 9603 9604 TypeSourceInfo *Sig = GetTypeForDeclarator(ParamInfo, CurScope); 9605 QualType T = Sig->getType(); 9606 9607 // FIXME: We should allow unexpanded parameter packs here, but that would, 9608 // in turn, make the block expression contain unexpanded parameter packs. 9609 if (DiagnoseUnexpandedParameterPack(CaretLoc, Sig, UPPC_Block)) { 9610 // Drop the parameters. 9611 FunctionProtoType::ExtProtoInfo EPI; 9612 EPI.HasTrailingReturn = false; 9613 EPI.TypeQuals |= DeclSpec::TQ_const; 9614 T = Context.getFunctionType(Context.DependentTy, ArrayRef<QualType>(), EPI); 9615 Sig = Context.getTrivialTypeSourceInfo(T); 9616 } 9617 9618 // GetTypeForDeclarator always produces a function type for a block 9619 // literal signature. Furthermore, it is always a FunctionProtoType 9620 // unless the function was written with a typedef. 9621 assert(T->isFunctionType() && 9622 "GetTypeForDeclarator made a non-function block signature"); 9623 9624 // Look for an explicit signature in that function type. 9625 FunctionProtoTypeLoc ExplicitSignature; 9626 9627 TypeLoc tmp = Sig->getTypeLoc().IgnoreParens(); 9628 if ((ExplicitSignature = tmp.getAs<FunctionProtoTypeLoc>())) { 9629 9630 // Check whether that explicit signature was synthesized by 9631 // GetTypeForDeclarator. If so, don't save that as part of the 9632 // written signature. 9633 if (ExplicitSignature.getLocalRangeBegin() == 9634 ExplicitSignature.getLocalRangeEnd()) { 9635 // This would be much cheaper if we stored TypeLocs instead of 9636 // TypeSourceInfos. 9637 TypeLoc Result = ExplicitSignature.getResultLoc(); 9638 unsigned Size = Result.getFullDataSize(); 9639 Sig = Context.CreateTypeSourceInfo(Result.getType(), Size); 9640 Sig->getTypeLoc().initializeFullCopy(Result, Size); 9641 9642 ExplicitSignature = FunctionProtoTypeLoc(); 9643 } 9644 } 9645 9646 CurBlock->TheDecl->setSignatureAsWritten(Sig); 9647 CurBlock->FunctionType = T; 9648 9649 const FunctionType *Fn = T->getAs<FunctionType>(); 9650 QualType RetTy = Fn->getResultType(); 9651 bool isVariadic = 9652 (isa<FunctionProtoType>(Fn) && cast<FunctionProtoType>(Fn)->isVariadic()); 9653 9654 CurBlock->TheDecl->setIsVariadic(isVariadic); 9655 9656 // Don't allow returning a objc interface by value. 9657 if (RetTy->isObjCObjectType()) { 9658 Diag(ParamInfo.getLocStart(), 9659 diag::err_object_cannot_be_passed_returned_by_value) << 0 << RetTy; 9660 return; 9661 } 9662 9663 // Context.DependentTy is used as a placeholder for a missing block 9664 // return type. TODO: what should we do with declarators like: 9665 // ^ * { ... } 9666 // If the answer is "apply template argument deduction".... 9667 if (RetTy != Context.DependentTy) { 9668 CurBlock->ReturnType = RetTy; 9669 CurBlock->TheDecl->setBlockMissingReturnType(false); 9670 CurBlock->HasImplicitReturnType = false; 9671 } 9672 9673 // Push block parameters from the declarator if we had them. 9674 SmallVector<ParmVarDecl*, 8> Params; 9675 if (ExplicitSignature) { 9676 for (unsigned I = 0, E = ExplicitSignature.getNumArgs(); I != E; ++I) { 9677 ParmVarDecl *Param = ExplicitSignature.getArg(I); 9678 if (Param->getIdentifier() == 0 && 9679 !Param->isImplicit() && 9680 !Param->isInvalidDecl() && 9681 !getLangOpts().CPlusPlus) 9682 Diag(Param->getLocation(), diag::err_parameter_name_omitted); 9683 Params.push_back(Param); 9684 } 9685 9686 // Fake up parameter variables if we have a typedef, like 9687 // ^ fntype { ... } 9688 } else if (const FunctionProtoType *Fn = T->getAs<FunctionProtoType>()) { 9689 for (FunctionProtoType::arg_type_iterator 9690 I = Fn->arg_type_begin(), E = Fn->arg_type_end(); I != E; ++I) { 9691 ParmVarDecl *Param = 9692 BuildParmVarDeclForTypedef(CurBlock->TheDecl, 9693 ParamInfo.getLocStart(), 9694 *I); 9695 Params.push_back(Param); 9696 } 9697 } 9698 9699 // Set the parameters on the block decl. 9700 if (!Params.empty()) { 9701 CurBlock->TheDecl->setParams(Params); 9702 CheckParmsForFunctionDef(CurBlock->TheDecl->param_begin(), 9703 CurBlock->TheDecl->param_end(), 9704 /*CheckParameterNames=*/false); 9705 } 9706 9707 // Finally we can process decl attributes. 9708 ProcessDeclAttributes(CurScope, CurBlock->TheDecl, ParamInfo); 9709 9710 // Put the parameter variables in scope. We can bail out immediately 9711 // if we don't have any. 9712 if (Params.empty()) 9713 return; 9714 9715 for (BlockDecl::param_iterator AI = CurBlock->TheDecl->param_begin(), 9716 E = CurBlock->TheDecl->param_end(); AI != E; ++AI) { 9717 (*AI)->setOwningFunction(CurBlock->TheDecl); 9718 9719 // If this has an identifier, add it to the scope stack. 9720 if ((*AI)->getIdentifier()) { 9721 CheckShadow(CurBlock->TheScope, *AI); 9722 9723 PushOnScopeChains(*AI, CurBlock->TheScope); 9724 } 9725 } 9726} 9727 9728/// ActOnBlockError - If there is an error parsing a block, this callback 9729/// is invoked to pop the information about the block from the action impl. 9730void Sema::ActOnBlockError(SourceLocation CaretLoc, Scope *CurScope) { 9731 // Leave the expression-evaluation context. 9732 DiscardCleanupsInEvaluationContext(); 9733 PopExpressionEvaluationContext(); 9734 9735 // Pop off CurBlock, handle nested blocks. 9736 PopDeclContext(); 9737 PopFunctionScopeInfo(); 9738} 9739 9740/// ActOnBlockStmtExpr - This is called when the body of a block statement 9741/// literal was successfully completed. ^(int x){...} 9742ExprResult Sema::ActOnBlockStmtExpr(SourceLocation CaretLoc, 9743 Stmt *Body, Scope *CurScope) { 9744 // If blocks are disabled, emit an error. 9745 if (!LangOpts.Blocks) 9746 Diag(CaretLoc, diag::err_blocks_disable); 9747 9748 // Leave the expression-evaluation context. 9749 if (hasAnyUnrecoverableErrorsInThisFunction()) 9750 DiscardCleanupsInEvaluationContext(); 9751 assert(!ExprNeedsCleanups && "cleanups within block not correctly bound!"); 9752 PopExpressionEvaluationContext(); 9753 9754 BlockScopeInfo *BSI = cast<BlockScopeInfo>(FunctionScopes.back()); 9755 9756 if (BSI->HasImplicitReturnType) 9757 deduceClosureReturnType(*BSI); 9758 9759 PopDeclContext(); 9760 9761 QualType RetTy = Context.VoidTy; 9762 if (!BSI->ReturnType.isNull()) 9763 RetTy = BSI->ReturnType; 9764 9765 bool NoReturn = BSI->TheDecl->getAttr<NoReturnAttr>(); 9766 QualType BlockTy; 9767 9768 // Set the captured variables on the block. 9769 // FIXME: Share capture structure between BlockDecl and CapturingScopeInfo! 9770 SmallVector<BlockDecl::Capture, 4> Captures; 9771 for (unsigned i = 0, e = BSI->Captures.size(); i != e; i++) { 9772 CapturingScopeInfo::Capture &Cap = BSI->Captures[i]; 9773 if (Cap.isThisCapture()) 9774 continue; 9775 BlockDecl::Capture NewCap(Cap.getVariable(), Cap.isBlockCapture(), 9776 Cap.isNested(), Cap.getCopyExpr()); 9777 Captures.push_back(NewCap); 9778 } 9779 BSI->TheDecl->setCaptures(Context, Captures.begin(), Captures.end(), 9780 BSI->CXXThisCaptureIndex != 0); 9781 9782 // If the user wrote a function type in some form, try to use that. 9783 if (!BSI->FunctionType.isNull()) { 9784 const FunctionType *FTy = BSI->FunctionType->getAs<FunctionType>(); 9785 9786 FunctionType::ExtInfo Ext = FTy->getExtInfo(); 9787 if (NoReturn && !Ext.getNoReturn()) Ext = Ext.withNoReturn(true); 9788 9789 // Turn protoless block types into nullary block types. 9790 if (isa<FunctionNoProtoType>(FTy)) { 9791 FunctionProtoType::ExtProtoInfo EPI; 9792 EPI.ExtInfo = Ext; 9793 BlockTy = Context.getFunctionType(RetTy, ArrayRef<QualType>(), EPI); 9794 9795 // Otherwise, if we don't need to change anything about the function type, 9796 // preserve its sugar structure. 9797 } else if (FTy->getResultType() == RetTy && 9798 (!NoReturn || FTy->getNoReturnAttr())) { 9799 BlockTy = BSI->FunctionType; 9800 9801 // Otherwise, make the minimal modifications to the function type. 9802 } else { 9803 const FunctionProtoType *FPT = cast<FunctionProtoType>(FTy); 9804 FunctionProtoType::ExtProtoInfo EPI = FPT->getExtProtoInfo(); 9805 EPI.TypeQuals = 0; // FIXME: silently? 9806 EPI.ExtInfo = Ext; 9807 BlockTy = 9808 Context.getFunctionType(RetTy, 9809 ArrayRef<QualType>(FPT->arg_type_begin(), 9810 FPT->getNumArgs()), 9811 EPI); 9812 } 9813 9814 // If we don't have a function type, just build one from nothing. 9815 } else { 9816 FunctionProtoType::ExtProtoInfo EPI; 9817 EPI.ExtInfo = FunctionType::ExtInfo().withNoReturn(NoReturn); 9818 BlockTy = Context.getFunctionType(RetTy, ArrayRef<QualType>(), EPI); 9819 } 9820 9821 DiagnoseUnusedParameters(BSI->TheDecl->param_begin(), 9822 BSI->TheDecl->param_end()); 9823 BlockTy = Context.getBlockPointerType(BlockTy); 9824 9825 // If needed, diagnose invalid gotos and switches in the block. 9826 if (getCurFunction()->NeedsScopeChecking() && 9827 !hasAnyUnrecoverableErrorsInThisFunction() && 9828 !PP.isCodeCompletionEnabled()) 9829 DiagnoseInvalidJumps(cast<CompoundStmt>(Body)); 9830 9831 BSI->TheDecl->setBody(cast<CompoundStmt>(Body)); 9832 9833 // Try to apply the named return value optimization. We have to check again 9834 // if we can do this, though, because blocks keep return statements around 9835 // to deduce an implicit return type. 9836 if (getLangOpts().CPlusPlus && RetTy->isRecordType() && 9837 !BSI->TheDecl->isDependentContext()) 9838 computeNRVO(Body, getCurBlock()); 9839 9840 BlockExpr *Result = new (Context) BlockExpr(BSI->TheDecl, BlockTy); 9841 const AnalysisBasedWarnings::Policy &WP = AnalysisWarnings.getDefaultPolicy(); 9842 PopFunctionScopeInfo(&WP, Result->getBlockDecl(), Result); 9843 9844 // If the block isn't obviously global, i.e. it captures anything at 9845 // all, then we need to do a few things in the surrounding context: 9846 if (Result->getBlockDecl()->hasCaptures()) { 9847 // First, this expression has a new cleanup object. 9848 ExprCleanupObjects.push_back(Result->getBlockDecl()); 9849 ExprNeedsCleanups = true; 9850 9851 // It also gets a branch-protected scope if any of the captured 9852 // variables needs destruction. 9853 for (BlockDecl::capture_const_iterator 9854 ci = Result->getBlockDecl()->capture_begin(), 9855 ce = Result->getBlockDecl()->capture_end(); ci != ce; ++ci) { 9856 const VarDecl *var = ci->getVariable(); 9857 if (var->getType().isDestructedType() != QualType::DK_none) { 9858 getCurFunction()->setHasBranchProtectedScope(); 9859 break; 9860 } 9861 } 9862 } 9863 9864 return Owned(Result); 9865} 9866 9867ExprResult Sema::ActOnVAArg(SourceLocation BuiltinLoc, 9868 Expr *E, ParsedType Ty, 9869 SourceLocation RPLoc) { 9870 TypeSourceInfo *TInfo; 9871 GetTypeFromParser(Ty, &TInfo); 9872 return BuildVAArgExpr(BuiltinLoc, E, TInfo, RPLoc); 9873} 9874 9875ExprResult Sema::BuildVAArgExpr(SourceLocation BuiltinLoc, 9876 Expr *E, TypeSourceInfo *TInfo, 9877 SourceLocation RPLoc) { 9878 Expr *OrigExpr = E; 9879 9880 // Get the va_list type 9881 QualType VaListType = Context.getBuiltinVaListType(); 9882 if (VaListType->isArrayType()) { 9883 // Deal with implicit array decay; for example, on x86-64, 9884 // va_list is an array, but it's supposed to decay to 9885 // a pointer for va_arg. 9886 VaListType = Context.getArrayDecayedType(VaListType); 9887 // Make sure the input expression also decays appropriately. 9888 ExprResult Result = UsualUnaryConversions(E); 9889 if (Result.isInvalid()) 9890 return ExprError(); 9891 E = Result.take(); 9892 } else if (VaListType->isRecordType() && getLangOpts().CPlusPlus) { 9893 // If va_list is a record type and we are compiling in C++ mode, 9894 // check the argument using reference binding. 9895 InitializedEntity Entity 9896 = InitializedEntity::InitializeParameter(Context, 9897 Context.getLValueReferenceType(VaListType), false); 9898 ExprResult Init = PerformCopyInitialization(Entity, SourceLocation(), E); 9899 if (Init.isInvalid()) 9900 return ExprError(); 9901 E = Init.takeAs<Expr>(); 9902 } else { 9903 // Otherwise, the va_list argument must be an l-value because 9904 // it is modified by va_arg. 9905 if (!E->isTypeDependent() && 9906 CheckForModifiableLvalue(E, BuiltinLoc, *this)) 9907 return ExprError(); 9908 } 9909 9910 if (!E->isTypeDependent() && 9911 !Context.hasSameType(VaListType, E->getType())) { 9912 return ExprError(Diag(E->getLocStart(), 9913 diag::err_first_argument_to_va_arg_not_of_type_va_list) 9914 << OrigExpr->getType() << E->getSourceRange()); 9915 } 9916 9917 if (!TInfo->getType()->isDependentType()) { 9918 if (RequireCompleteType(TInfo->getTypeLoc().getBeginLoc(), TInfo->getType(), 9919 diag::err_second_parameter_to_va_arg_incomplete, 9920 TInfo->getTypeLoc())) 9921 return ExprError(); 9922 9923 if (RequireNonAbstractType(TInfo->getTypeLoc().getBeginLoc(), 9924 TInfo->getType(), 9925 diag::err_second_parameter_to_va_arg_abstract, 9926 TInfo->getTypeLoc())) 9927 return ExprError(); 9928 9929 if (!TInfo->getType().isPODType(Context)) { 9930 Diag(TInfo->getTypeLoc().getBeginLoc(), 9931 TInfo->getType()->isObjCLifetimeType() 9932 ? diag::warn_second_parameter_to_va_arg_ownership_qualified 9933 : diag::warn_second_parameter_to_va_arg_not_pod) 9934 << TInfo->getType() 9935 << TInfo->getTypeLoc().getSourceRange(); 9936 } 9937 9938 // Check for va_arg where arguments of the given type will be promoted 9939 // (i.e. this va_arg is guaranteed to have undefined behavior). 9940 QualType PromoteType; 9941 if (TInfo->getType()->isPromotableIntegerType()) { 9942 PromoteType = Context.getPromotedIntegerType(TInfo->getType()); 9943 if (Context.typesAreCompatible(PromoteType, TInfo->getType())) 9944 PromoteType = QualType(); 9945 } 9946 if (TInfo->getType()->isSpecificBuiltinType(BuiltinType::Float)) 9947 PromoteType = Context.DoubleTy; 9948 if (!PromoteType.isNull()) 9949 DiagRuntimeBehavior(TInfo->getTypeLoc().getBeginLoc(), E, 9950 PDiag(diag::warn_second_parameter_to_va_arg_never_compatible) 9951 << TInfo->getType() 9952 << PromoteType 9953 << TInfo->getTypeLoc().getSourceRange()); 9954 } 9955 9956 QualType T = TInfo->getType().getNonLValueExprType(Context); 9957 return Owned(new (Context) VAArgExpr(BuiltinLoc, E, TInfo, RPLoc, T)); 9958} 9959 9960ExprResult Sema::ActOnGNUNullExpr(SourceLocation TokenLoc) { 9961 // The type of __null will be int or long, depending on the size of 9962 // pointers on the target. 9963 QualType Ty; 9964 unsigned pw = Context.getTargetInfo().getPointerWidth(0); 9965 if (pw == Context.getTargetInfo().getIntWidth()) 9966 Ty = Context.IntTy; 9967 else if (pw == Context.getTargetInfo().getLongWidth()) 9968 Ty = Context.LongTy; 9969 else if (pw == Context.getTargetInfo().getLongLongWidth()) 9970 Ty = Context.LongLongTy; 9971 else { 9972 llvm_unreachable("I don't know size of pointer!"); 9973 } 9974 9975 return Owned(new (Context) GNUNullExpr(Ty, TokenLoc)); 9976} 9977 9978static void MakeObjCStringLiteralFixItHint(Sema& SemaRef, QualType DstType, 9979 Expr *SrcExpr, FixItHint &Hint) { 9980 if (!SemaRef.getLangOpts().ObjC1) 9981 return; 9982 9983 const ObjCObjectPointerType *PT = DstType->getAs<ObjCObjectPointerType>(); 9984 if (!PT) 9985 return; 9986 9987 // Check if the destination is of type 'id'. 9988 if (!PT->isObjCIdType()) { 9989 // Check if the destination is the 'NSString' interface. 9990 const ObjCInterfaceDecl *ID = PT->getInterfaceDecl(); 9991 if (!ID || !ID->getIdentifier()->isStr("NSString")) 9992 return; 9993 } 9994 9995 // Ignore any parens, implicit casts (should only be 9996 // array-to-pointer decays), and not-so-opaque values. The last is 9997 // important for making this trigger for property assignments. 9998 SrcExpr = SrcExpr->IgnoreParenImpCasts(); 9999 if (OpaqueValueExpr *OV = dyn_cast<OpaqueValueExpr>(SrcExpr)) 10000 if (OV->getSourceExpr()) 10001 SrcExpr = OV->getSourceExpr()->IgnoreParenImpCasts(); 10002 10003 StringLiteral *SL = dyn_cast<StringLiteral>(SrcExpr); 10004 if (!SL || !SL->isAscii()) 10005 return; 10006 10007 Hint = FixItHint::CreateInsertion(SL->getLocStart(), "@"); 10008} 10009 10010bool Sema::DiagnoseAssignmentResult(AssignConvertType ConvTy, 10011 SourceLocation Loc, 10012 QualType DstType, QualType SrcType, 10013 Expr *SrcExpr, AssignmentAction Action, 10014 bool *Complained) { 10015 if (Complained) 10016 *Complained = false; 10017 10018 // Decode the result (notice that AST's are still created for extensions). 10019 bool CheckInferredResultType = false; 10020 bool isInvalid = false; 10021 unsigned DiagKind = 0; 10022 FixItHint Hint; 10023 ConversionFixItGenerator ConvHints; 10024 bool MayHaveConvFixit = false; 10025 bool MayHaveFunctionDiff = false; 10026 10027 switch (ConvTy) { 10028 case Compatible: 10029 DiagnoseAssignmentEnum(DstType, SrcType, SrcExpr); 10030 return false; 10031 10032 case PointerToInt: 10033 DiagKind = diag::ext_typecheck_convert_pointer_int; 10034 ConvHints.tryToFixConversion(SrcExpr, SrcType, DstType, *this); 10035 MayHaveConvFixit = true; 10036 break; 10037 case IntToPointer: 10038 DiagKind = diag::ext_typecheck_convert_int_pointer; 10039 ConvHints.tryToFixConversion(SrcExpr, SrcType, DstType, *this); 10040 MayHaveConvFixit = true; 10041 break; 10042 case IncompatiblePointer: 10043 MakeObjCStringLiteralFixItHint(*this, DstType, SrcExpr, Hint); 10044 DiagKind = diag::ext_typecheck_convert_incompatible_pointer; 10045 CheckInferredResultType = DstType->isObjCObjectPointerType() && 10046 SrcType->isObjCObjectPointerType(); 10047 if (Hint.isNull() && !CheckInferredResultType) { 10048 ConvHints.tryToFixConversion(SrcExpr, SrcType, DstType, *this); 10049 } 10050 MayHaveConvFixit = true; 10051 break; 10052 case IncompatiblePointerSign: 10053 DiagKind = diag::ext_typecheck_convert_incompatible_pointer_sign; 10054 break; 10055 case FunctionVoidPointer: 10056 DiagKind = diag::ext_typecheck_convert_pointer_void_func; 10057 break; 10058 case IncompatiblePointerDiscardsQualifiers: { 10059 // Perform array-to-pointer decay if necessary. 10060 if (SrcType->isArrayType()) SrcType = Context.getArrayDecayedType(SrcType); 10061 10062 Qualifiers lhq = SrcType->getPointeeType().getQualifiers(); 10063 Qualifiers rhq = DstType->getPointeeType().getQualifiers(); 10064 if (lhq.getAddressSpace() != rhq.getAddressSpace()) { 10065 DiagKind = diag::err_typecheck_incompatible_address_space; 10066 break; 10067 10068 10069 } else if (lhq.getObjCLifetime() != rhq.getObjCLifetime()) { 10070 DiagKind = diag::err_typecheck_incompatible_ownership; 10071 break; 10072 } 10073 10074 llvm_unreachable("unknown error case for discarding qualifiers!"); 10075 // fallthrough 10076 } 10077 case CompatiblePointerDiscardsQualifiers: 10078 // If the qualifiers lost were because we were applying the 10079 // (deprecated) C++ conversion from a string literal to a char* 10080 // (or wchar_t*), then there was no error (C++ 4.2p2). FIXME: 10081 // Ideally, this check would be performed in 10082 // checkPointerTypesForAssignment. However, that would require a 10083 // bit of refactoring (so that the second argument is an 10084 // expression, rather than a type), which should be done as part 10085 // of a larger effort to fix checkPointerTypesForAssignment for 10086 // C++ semantics. 10087 if (getLangOpts().CPlusPlus && 10088 IsStringLiteralToNonConstPointerConversion(SrcExpr, DstType)) 10089 return false; 10090 DiagKind = diag::ext_typecheck_convert_discards_qualifiers; 10091 break; 10092 case IncompatibleNestedPointerQualifiers: 10093 DiagKind = diag::ext_nested_pointer_qualifier_mismatch; 10094 break; 10095 case IntToBlockPointer: 10096 DiagKind = diag::err_int_to_block_pointer; 10097 break; 10098 case IncompatibleBlockPointer: 10099 DiagKind = diag::err_typecheck_convert_incompatible_block_pointer; 10100 break; 10101 case IncompatibleObjCQualifiedId: 10102 // FIXME: Diagnose the problem in ObjCQualifiedIdTypesAreCompatible, since 10103 // it can give a more specific diagnostic. 10104 DiagKind = diag::warn_incompatible_qualified_id; 10105 break; 10106 case IncompatibleVectors: 10107 DiagKind = diag::warn_incompatible_vectors; 10108 break; 10109 case IncompatibleObjCWeakRef: 10110 DiagKind = diag::err_arc_weak_unavailable_assign; 10111 break; 10112 case Incompatible: 10113 DiagKind = diag::err_typecheck_convert_incompatible; 10114 ConvHints.tryToFixConversion(SrcExpr, SrcType, DstType, *this); 10115 MayHaveConvFixit = true; 10116 isInvalid = true; 10117 MayHaveFunctionDiff = true; 10118 break; 10119 } 10120 10121 QualType FirstType, SecondType; 10122 switch (Action) { 10123 case AA_Assigning: 10124 case AA_Initializing: 10125 // The destination type comes first. 10126 FirstType = DstType; 10127 SecondType = SrcType; 10128 break; 10129 10130 case AA_Returning: 10131 case AA_Passing: 10132 case AA_Converting: 10133 case AA_Sending: 10134 case AA_Casting: 10135 // The source type comes first. 10136 FirstType = SrcType; 10137 SecondType = DstType; 10138 break; 10139 } 10140 10141 PartialDiagnostic FDiag = PDiag(DiagKind); 10142 FDiag << FirstType << SecondType << Action << SrcExpr->getSourceRange(); 10143 10144 // If we can fix the conversion, suggest the FixIts. 10145 assert(ConvHints.isNull() || Hint.isNull()); 10146 if (!ConvHints.isNull()) { 10147 for (std::vector<FixItHint>::iterator HI = ConvHints.Hints.begin(), 10148 HE = ConvHints.Hints.end(); HI != HE; ++HI) 10149 FDiag << *HI; 10150 } else { 10151 FDiag << Hint; 10152 } 10153 if (MayHaveConvFixit) { FDiag << (unsigned) (ConvHints.Kind); } 10154 10155 if (MayHaveFunctionDiff) 10156 HandleFunctionTypeMismatch(FDiag, SecondType, FirstType); 10157 10158 Diag(Loc, FDiag); 10159 10160 if (SecondType == Context.OverloadTy) 10161 NoteAllOverloadCandidates(OverloadExpr::find(SrcExpr).Expression, 10162 FirstType); 10163 10164 if (CheckInferredResultType) 10165 EmitRelatedResultTypeNote(SrcExpr); 10166 10167 if (Action == AA_Returning && ConvTy == IncompatiblePointer) 10168 EmitRelatedResultTypeNoteForReturn(DstType); 10169 10170 if (Complained) 10171 *Complained = true; 10172 return isInvalid; 10173} 10174 10175ExprResult Sema::VerifyIntegerConstantExpression(Expr *E, 10176 llvm::APSInt *Result) { 10177 class SimpleICEDiagnoser : public VerifyICEDiagnoser { 10178 public: 10179 virtual void diagnoseNotICE(Sema &S, SourceLocation Loc, SourceRange SR) { 10180 S.Diag(Loc, diag::err_expr_not_ice) << S.LangOpts.CPlusPlus << SR; 10181 } 10182 } Diagnoser; 10183 10184 return VerifyIntegerConstantExpression(E, Result, Diagnoser); 10185} 10186 10187ExprResult Sema::VerifyIntegerConstantExpression(Expr *E, 10188 llvm::APSInt *Result, 10189 unsigned DiagID, 10190 bool AllowFold) { 10191 class IDDiagnoser : public VerifyICEDiagnoser { 10192 unsigned DiagID; 10193 10194 public: 10195 IDDiagnoser(unsigned DiagID) 10196 : VerifyICEDiagnoser(DiagID == 0), DiagID(DiagID) { } 10197 10198 virtual void diagnoseNotICE(Sema &S, SourceLocation Loc, SourceRange SR) { 10199 S.Diag(Loc, DiagID) << SR; 10200 } 10201 } Diagnoser(DiagID); 10202 10203 return VerifyIntegerConstantExpression(E, Result, Diagnoser, AllowFold); 10204} 10205 10206void Sema::VerifyICEDiagnoser::diagnoseFold(Sema &S, SourceLocation Loc, 10207 SourceRange SR) { 10208 S.Diag(Loc, diag::ext_expr_not_ice) << SR << S.LangOpts.CPlusPlus; 10209} 10210 10211ExprResult 10212Sema::VerifyIntegerConstantExpression(Expr *E, llvm::APSInt *Result, 10213 VerifyICEDiagnoser &Diagnoser, 10214 bool AllowFold) { 10215 SourceLocation DiagLoc = E->getLocStart(); 10216 10217 if (getLangOpts().CPlusPlus11) { 10218 // C++11 [expr.const]p5: 10219 // If an expression of literal class type is used in a context where an 10220 // integral constant expression is required, then that class type shall 10221 // have a single non-explicit conversion function to an integral or 10222 // unscoped enumeration type 10223 ExprResult Converted; 10224 if (!Diagnoser.Suppress) { 10225 class CXX11ConvertDiagnoser : public ICEConvertDiagnoser { 10226 public: 10227 CXX11ConvertDiagnoser() : ICEConvertDiagnoser(false, true) { } 10228 10229 virtual DiagnosticBuilder diagnoseNotInt(Sema &S, SourceLocation Loc, 10230 QualType T) { 10231 return S.Diag(Loc, diag::err_ice_not_integral) << T; 10232 } 10233 10234 virtual DiagnosticBuilder diagnoseIncomplete(Sema &S, 10235 SourceLocation Loc, 10236 QualType T) { 10237 return S.Diag(Loc, diag::err_ice_incomplete_type) << T; 10238 } 10239 10240 virtual DiagnosticBuilder diagnoseExplicitConv(Sema &S, 10241 SourceLocation Loc, 10242 QualType T, 10243 QualType ConvTy) { 10244 return S.Diag(Loc, diag::err_ice_explicit_conversion) << T << ConvTy; 10245 } 10246 10247 virtual DiagnosticBuilder noteExplicitConv(Sema &S, 10248 CXXConversionDecl *Conv, 10249 QualType ConvTy) { 10250 return S.Diag(Conv->getLocation(), diag::note_ice_conversion_here) 10251 << ConvTy->isEnumeralType() << ConvTy; 10252 } 10253 10254 virtual DiagnosticBuilder diagnoseAmbiguous(Sema &S, SourceLocation Loc, 10255 QualType T) { 10256 return S.Diag(Loc, diag::err_ice_ambiguous_conversion) << T; 10257 } 10258 10259 virtual DiagnosticBuilder noteAmbiguous(Sema &S, 10260 CXXConversionDecl *Conv, 10261 QualType ConvTy) { 10262 return S.Diag(Conv->getLocation(), diag::note_ice_conversion_here) 10263 << ConvTy->isEnumeralType() << ConvTy; 10264 } 10265 10266 virtual DiagnosticBuilder diagnoseConversion(Sema &S, 10267 SourceLocation Loc, 10268 QualType T, 10269 QualType ConvTy) { 10270 return DiagnosticBuilder::getEmpty(); 10271 } 10272 } ConvertDiagnoser; 10273 10274 Converted = ConvertToIntegralOrEnumerationType(DiagLoc, E, 10275 ConvertDiagnoser, 10276 /*AllowScopedEnumerations*/ false); 10277 } else { 10278 // The caller wants to silently enquire whether this is an ICE. Don't 10279 // produce any diagnostics if it isn't. 10280 class SilentICEConvertDiagnoser : public ICEConvertDiagnoser { 10281 public: 10282 SilentICEConvertDiagnoser() : ICEConvertDiagnoser(true, true) { } 10283 10284 virtual DiagnosticBuilder diagnoseNotInt(Sema &S, SourceLocation Loc, 10285 QualType T) { 10286 return DiagnosticBuilder::getEmpty(); 10287 } 10288 10289 virtual DiagnosticBuilder diagnoseIncomplete(Sema &S, 10290 SourceLocation Loc, 10291 QualType T) { 10292 return DiagnosticBuilder::getEmpty(); 10293 } 10294 10295 virtual DiagnosticBuilder diagnoseExplicitConv(Sema &S, 10296 SourceLocation Loc, 10297 QualType T, 10298 QualType ConvTy) { 10299 return DiagnosticBuilder::getEmpty(); 10300 } 10301 10302 virtual DiagnosticBuilder noteExplicitConv(Sema &S, 10303 CXXConversionDecl *Conv, 10304 QualType ConvTy) { 10305 return DiagnosticBuilder::getEmpty(); 10306 } 10307 10308 virtual DiagnosticBuilder diagnoseAmbiguous(Sema &S, SourceLocation Loc, 10309 QualType T) { 10310 return DiagnosticBuilder::getEmpty(); 10311 } 10312 10313 virtual DiagnosticBuilder noteAmbiguous(Sema &S, 10314 CXXConversionDecl *Conv, 10315 QualType ConvTy) { 10316 return DiagnosticBuilder::getEmpty(); 10317 } 10318 10319 virtual DiagnosticBuilder diagnoseConversion(Sema &S, 10320 SourceLocation Loc, 10321 QualType T, 10322 QualType ConvTy) { 10323 return DiagnosticBuilder::getEmpty(); 10324 } 10325 } ConvertDiagnoser; 10326 10327 Converted = ConvertToIntegralOrEnumerationType(DiagLoc, E, 10328 ConvertDiagnoser, false); 10329 } 10330 if (Converted.isInvalid()) 10331 return Converted; 10332 E = Converted.take(); 10333 if (!E->getType()->isIntegralOrUnscopedEnumerationType()) 10334 return ExprError(); 10335 } else if (!E->getType()->isIntegralOrUnscopedEnumerationType()) { 10336 // An ICE must be of integral or unscoped enumeration type. 10337 if (!Diagnoser.Suppress) 10338 Diagnoser.diagnoseNotICE(*this, DiagLoc, E->getSourceRange()); 10339 return ExprError(); 10340 } 10341 10342 // Circumvent ICE checking in C++11 to avoid evaluating the expression twice 10343 // in the non-ICE case. 10344 if (!getLangOpts().CPlusPlus11 && E->isIntegerConstantExpr(Context)) { 10345 if (Result) 10346 *Result = E->EvaluateKnownConstInt(Context); 10347 return Owned(E); 10348 } 10349 10350 Expr::EvalResult EvalResult; 10351 SmallVector<PartialDiagnosticAt, 8> Notes; 10352 EvalResult.Diag = &Notes; 10353 10354 // Try to evaluate the expression, and produce diagnostics explaining why it's 10355 // not a constant expression as a side-effect. 10356 bool Folded = E->EvaluateAsRValue(EvalResult, Context) && 10357 EvalResult.Val.isInt() && !EvalResult.HasSideEffects; 10358 10359 // In C++11, we can rely on diagnostics being produced for any expression 10360 // which is not a constant expression. If no diagnostics were produced, then 10361 // this is a constant expression. 10362 if (Folded && getLangOpts().CPlusPlus11 && Notes.empty()) { 10363 if (Result) 10364 *Result = EvalResult.Val.getInt(); 10365 return Owned(E); 10366 } 10367 10368 // If our only note is the usual "invalid subexpression" note, just point 10369 // the caret at its location rather than producing an essentially 10370 // redundant note. 10371 if (Notes.size() == 1 && Notes[0].second.getDiagID() == 10372 diag::note_invalid_subexpr_in_const_expr) { 10373 DiagLoc = Notes[0].first; 10374 Notes.clear(); 10375 } 10376 10377 if (!Folded || !AllowFold) { 10378 if (!Diagnoser.Suppress) { 10379 Diagnoser.diagnoseNotICE(*this, DiagLoc, E->getSourceRange()); 10380 for (unsigned I = 0, N = Notes.size(); I != N; ++I) 10381 Diag(Notes[I].first, Notes[I].second); 10382 } 10383 10384 return ExprError(); 10385 } 10386 10387 Diagnoser.diagnoseFold(*this, DiagLoc, E->getSourceRange()); 10388 for (unsigned I = 0, N = Notes.size(); I != N; ++I) 10389 Diag(Notes[I].first, Notes[I].second); 10390 10391 if (Result) 10392 *Result = EvalResult.Val.getInt(); 10393 return Owned(E); 10394} 10395 10396namespace { 10397 // Handle the case where we conclude a expression which we speculatively 10398 // considered to be unevaluated is actually evaluated. 10399 class TransformToPE : public TreeTransform<TransformToPE> { 10400 typedef TreeTransform<TransformToPE> BaseTransform; 10401 10402 public: 10403 TransformToPE(Sema &SemaRef) : BaseTransform(SemaRef) { } 10404 10405 // Make sure we redo semantic analysis 10406 bool AlwaysRebuild() { return true; } 10407 10408 // Make sure we handle LabelStmts correctly. 10409 // FIXME: This does the right thing, but maybe we need a more general 10410 // fix to TreeTransform? 10411 StmtResult TransformLabelStmt(LabelStmt *S) { 10412 S->getDecl()->setStmt(0); 10413 return BaseTransform::TransformLabelStmt(S); 10414 } 10415 10416 // We need to special-case DeclRefExprs referring to FieldDecls which 10417 // are not part of a member pointer formation; normal TreeTransforming 10418 // doesn't catch this case because of the way we represent them in the AST. 10419 // FIXME: This is a bit ugly; is it really the best way to handle this 10420 // case? 10421 // 10422 // Error on DeclRefExprs referring to FieldDecls. 10423 ExprResult TransformDeclRefExpr(DeclRefExpr *E) { 10424 if (isa<FieldDecl>(E->getDecl()) && 10425 !SemaRef.isUnevaluatedContext()) 10426 return SemaRef.Diag(E->getLocation(), 10427 diag::err_invalid_non_static_member_use) 10428 << E->getDecl() << E->getSourceRange(); 10429 10430 return BaseTransform::TransformDeclRefExpr(E); 10431 } 10432 10433 // Exception: filter out member pointer formation 10434 ExprResult TransformUnaryOperator(UnaryOperator *E) { 10435 if (E->getOpcode() == UO_AddrOf && E->getType()->isMemberPointerType()) 10436 return E; 10437 10438 return BaseTransform::TransformUnaryOperator(E); 10439 } 10440 10441 ExprResult TransformLambdaExpr(LambdaExpr *E) { 10442 // Lambdas never need to be transformed. 10443 return E; 10444 } 10445 }; 10446} 10447 10448ExprResult Sema::TransformToPotentiallyEvaluated(Expr *E) { 10449 assert(ExprEvalContexts.back().Context == Unevaluated && 10450 "Should only transform unevaluated expressions"); 10451 ExprEvalContexts.back().Context = 10452 ExprEvalContexts[ExprEvalContexts.size()-2].Context; 10453 if (ExprEvalContexts.back().Context == Unevaluated) 10454 return E; 10455 return TransformToPE(*this).TransformExpr(E); 10456} 10457 10458void 10459Sema::PushExpressionEvaluationContext(ExpressionEvaluationContext NewContext, 10460 Decl *LambdaContextDecl, 10461 bool IsDecltype) { 10462 ExprEvalContexts.push_back( 10463 ExpressionEvaluationContextRecord(NewContext, 10464 ExprCleanupObjects.size(), 10465 ExprNeedsCleanups, 10466 LambdaContextDecl, 10467 IsDecltype)); 10468 ExprNeedsCleanups = false; 10469 if (!MaybeODRUseExprs.empty()) 10470 std::swap(MaybeODRUseExprs, ExprEvalContexts.back().SavedMaybeODRUseExprs); 10471} 10472 10473void 10474Sema::PushExpressionEvaluationContext(ExpressionEvaluationContext NewContext, 10475 ReuseLambdaContextDecl_t, 10476 bool IsDecltype) { 10477 Decl *LambdaContextDecl = ExprEvalContexts.back().LambdaContextDecl; 10478 PushExpressionEvaluationContext(NewContext, LambdaContextDecl, IsDecltype); 10479} 10480 10481void Sema::PopExpressionEvaluationContext() { 10482 ExpressionEvaluationContextRecord& Rec = ExprEvalContexts.back(); 10483 10484 if (!Rec.Lambdas.empty()) { 10485 if (Rec.Context == Unevaluated) { 10486 // C++11 [expr.prim.lambda]p2: 10487 // A lambda-expression shall not appear in an unevaluated operand 10488 // (Clause 5). 10489 for (unsigned I = 0, N = Rec.Lambdas.size(); I != N; ++I) 10490 Diag(Rec.Lambdas[I]->getLocStart(), 10491 diag::err_lambda_unevaluated_operand); 10492 } else { 10493 // Mark the capture expressions odr-used. This was deferred 10494 // during lambda expression creation. 10495 for (unsigned I = 0, N = Rec.Lambdas.size(); I != N; ++I) { 10496 LambdaExpr *Lambda = Rec.Lambdas[I]; 10497 for (LambdaExpr::capture_init_iterator 10498 C = Lambda->capture_init_begin(), 10499 CEnd = Lambda->capture_init_end(); 10500 C != CEnd; ++C) { 10501 MarkDeclarationsReferencedInExpr(*C); 10502 } 10503 } 10504 } 10505 } 10506 10507 // When are coming out of an unevaluated context, clear out any 10508 // temporaries that we may have created as part of the evaluation of 10509 // the expression in that context: they aren't relevant because they 10510 // will never be constructed. 10511 if (Rec.Context == Unevaluated || Rec.Context == ConstantEvaluated) { 10512 ExprCleanupObjects.erase(ExprCleanupObjects.begin() + Rec.NumCleanupObjects, 10513 ExprCleanupObjects.end()); 10514 ExprNeedsCleanups = Rec.ParentNeedsCleanups; 10515 CleanupVarDeclMarking(); 10516 std::swap(MaybeODRUseExprs, Rec.SavedMaybeODRUseExprs); 10517 // Otherwise, merge the contexts together. 10518 } else { 10519 ExprNeedsCleanups |= Rec.ParentNeedsCleanups; 10520 MaybeODRUseExprs.insert(Rec.SavedMaybeODRUseExprs.begin(), 10521 Rec.SavedMaybeODRUseExprs.end()); 10522 } 10523 10524 // Pop the current expression evaluation context off the stack. 10525 ExprEvalContexts.pop_back(); 10526} 10527 10528void Sema::DiscardCleanupsInEvaluationContext() { 10529 ExprCleanupObjects.erase( 10530 ExprCleanupObjects.begin() + ExprEvalContexts.back().NumCleanupObjects, 10531 ExprCleanupObjects.end()); 10532 ExprNeedsCleanups = false; 10533 MaybeODRUseExprs.clear(); 10534} 10535 10536ExprResult Sema::HandleExprEvaluationContextForTypeof(Expr *E) { 10537 if (!E->getType()->isVariablyModifiedType()) 10538 return E; 10539 return TransformToPotentiallyEvaluated(E); 10540} 10541 10542static bool IsPotentiallyEvaluatedContext(Sema &SemaRef) { 10543 // Do not mark anything as "used" within a dependent context; wait for 10544 // an instantiation. 10545 if (SemaRef.CurContext->isDependentContext()) 10546 return false; 10547 10548 switch (SemaRef.ExprEvalContexts.back().Context) { 10549 case Sema::Unevaluated: 10550 // We are in an expression that is not potentially evaluated; do nothing. 10551 // (Depending on how you read the standard, we actually do need to do 10552 // something here for null pointer constants, but the standard's 10553 // definition of a null pointer constant is completely crazy.) 10554 return false; 10555 10556 case Sema::ConstantEvaluated: 10557 case Sema::PotentiallyEvaluated: 10558 // We are in a potentially evaluated expression (or a constant-expression 10559 // in C++03); we need to do implicit template instantiation, implicitly 10560 // define class members, and mark most declarations as used. 10561 return true; 10562 10563 case Sema::PotentiallyEvaluatedIfUsed: 10564 // Referenced declarations will only be used if the construct in the 10565 // containing expression is used. 10566 return false; 10567 } 10568 llvm_unreachable("Invalid context"); 10569} 10570 10571/// \brief Mark a function referenced, and check whether it is odr-used 10572/// (C++ [basic.def.odr]p2, C99 6.9p3) 10573void Sema::MarkFunctionReferenced(SourceLocation Loc, FunctionDecl *Func) { 10574 assert(Func && "No function?"); 10575 10576 Func->setReferenced(); 10577 10578 // C++11 [basic.def.odr]p3: 10579 // A function whose name appears as a potentially-evaluated expression is 10580 // odr-used if it is the unique lookup result or the selected member of a 10581 // set of overloaded functions [...]. 10582 // 10583 // We (incorrectly) mark overload resolution as an unevaluated context, so we 10584 // can just check that here. Skip the rest of this function if we've already 10585 // marked the function as used. 10586 if (Func->isUsed(false) || !IsPotentiallyEvaluatedContext(*this)) { 10587 // C++11 [temp.inst]p3: 10588 // Unless a function template specialization has been explicitly 10589 // instantiated or explicitly specialized, the function template 10590 // specialization is implicitly instantiated when the specialization is 10591 // referenced in a context that requires a function definition to exist. 10592 // 10593 // We consider constexpr function templates to be referenced in a context 10594 // that requires a definition to exist whenever they are referenced. 10595 // 10596 // FIXME: This instantiates constexpr functions too frequently. If this is 10597 // really an unevaluated context (and we're not just in the definition of a 10598 // function template or overload resolution or other cases which we 10599 // incorrectly consider to be unevaluated contexts), and we're not in a 10600 // subexpression which we actually need to evaluate (for instance, a 10601 // template argument, array bound or an expression in a braced-init-list), 10602 // we are not permitted to instantiate this constexpr function definition. 10603 // 10604 // FIXME: This also implicitly defines special members too frequently. They 10605 // are only supposed to be implicitly defined if they are odr-used, but they 10606 // are not odr-used from constant expressions in unevaluated contexts. 10607 // However, they cannot be referenced if they are deleted, and they are 10608 // deleted whenever the implicit definition of the special member would 10609 // fail. 10610 if (!Func->isConstexpr() || Func->getBody()) 10611 return; 10612 CXXMethodDecl *MD = dyn_cast<CXXMethodDecl>(Func); 10613 if (!Func->isImplicitlyInstantiable() && (!MD || MD->isUserProvided())) 10614 return; 10615 } 10616 10617 // Note that this declaration has been used. 10618 if (CXXConstructorDecl *Constructor = dyn_cast<CXXConstructorDecl>(Func)) { 10619 if (Constructor->isDefaulted() && !Constructor->isDeleted()) { 10620 if (Constructor->isDefaultConstructor()) { 10621 if (Constructor->isTrivial()) 10622 return; 10623 if (!Constructor->isUsed(false)) 10624 DefineImplicitDefaultConstructor(Loc, Constructor); 10625 } else if (Constructor->isCopyConstructor()) { 10626 if (!Constructor->isUsed(false)) 10627 DefineImplicitCopyConstructor(Loc, Constructor); 10628 } else if (Constructor->isMoveConstructor()) { 10629 if (!Constructor->isUsed(false)) 10630 DefineImplicitMoveConstructor(Loc, Constructor); 10631 } 10632 } else if (Constructor->getInheritedConstructor()) { 10633 if (!Constructor->isUsed(false)) 10634 DefineInheritingConstructor(Loc, Constructor); 10635 } 10636 10637 MarkVTableUsed(Loc, Constructor->getParent()); 10638 } else if (CXXDestructorDecl *Destructor = 10639 dyn_cast<CXXDestructorDecl>(Func)) { 10640 if (Destructor->isDefaulted() && !Destructor->isDeleted() && 10641 !Destructor->isUsed(false)) 10642 DefineImplicitDestructor(Loc, Destructor); 10643 if (Destructor->isVirtual()) 10644 MarkVTableUsed(Loc, Destructor->getParent()); 10645 } else if (CXXMethodDecl *MethodDecl = dyn_cast<CXXMethodDecl>(Func)) { 10646 if (MethodDecl->isDefaulted() && !MethodDecl->isDeleted() && 10647 MethodDecl->isOverloadedOperator() && 10648 MethodDecl->getOverloadedOperator() == OO_Equal) { 10649 if (!MethodDecl->isUsed(false)) { 10650 if (MethodDecl->isCopyAssignmentOperator()) 10651 DefineImplicitCopyAssignment(Loc, MethodDecl); 10652 else 10653 DefineImplicitMoveAssignment(Loc, MethodDecl); 10654 } 10655 } else if (isa<CXXConversionDecl>(MethodDecl) && 10656 MethodDecl->getParent()->isLambda()) { 10657 CXXConversionDecl *Conversion = cast<CXXConversionDecl>(MethodDecl); 10658 if (Conversion->isLambdaToBlockPointerConversion()) 10659 DefineImplicitLambdaToBlockPointerConversion(Loc, Conversion); 10660 else 10661 DefineImplicitLambdaToFunctionPointerConversion(Loc, Conversion); 10662 } else if (MethodDecl->isVirtual()) 10663 MarkVTableUsed(Loc, MethodDecl->getParent()); 10664 } 10665 10666 // Recursive functions should be marked when used from another function. 10667 // FIXME: Is this really right? 10668 if (CurContext == Func) return; 10669 10670 // Resolve the exception specification for any function which is 10671 // used: CodeGen will need it. 10672 const FunctionProtoType *FPT = Func->getType()->getAs<FunctionProtoType>(); 10673 if (FPT && isUnresolvedExceptionSpec(FPT->getExceptionSpecType())) 10674 ResolveExceptionSpec(Loc, FPT); 10675 10676 // Implicit instantiation of function templates and member functions of 10677 // class templates. 10678 if (Func->isImplicitlyInstantiable()) { 10679 bool AlreadyInstantiated = false; 10680 SourceLocation PointOfInstantiation = Loc; 10681 if (FunctionTemplateSpecializationInfo *SpecInfo 10682 = Func->getTemplateSpecializationInfo()) { 10683 if (SpecInfo->getPointOfInstantiation().isInvalid()) 10684 SpecInfo->setPointOfInstantiation(Loc); 10685 else if (SpecInfo->getTemplateSpecializationKind() 10686 == TSK_ImplicitInstantiation) { 10687 AlreadyInstantiated = true; 10688 PointOfInstantiation = SpecInfo->getPointOfInstantiation(); 10689 } 10690 } else if (MemberSpecializationInfo *MSInfo 10691 = Func->getMemberSpecializationInfo()) { 10692 if (MSInfo->getPointOfInstantiation().isInvalid()) 10693 MSInfo->setPointOfInstantiation(Loc); 10694 else if (MSInfo->getTemplateSpecializationKind() 10695 == TSK_ImplicitInstantiation) { 10696 AlreadyInstantiated = true; 10697 PointOfInstantiation = MSInfo->getPointOfInstantiation(); 10698 } 10699 } 10700 10701 if (!AlreadyInstantiated || Func->isConstexpr()) { 10702 if (isa<CXXRecordDecl>(Func->getDeclContext()) && 10703 cast<CXXRecordDecl>(Func->getDeclContext())->isLocalClass()) 10704 PendingLocalImplicitInstantiations.push_back( 10705 std::make_pair(Func, PointOfInstantiation)); 10706 else if (Func->isConstexpr()) 10707 // Do not defer instantiations of constexpr functions, to avoid the 10708 // expression evaluator needing to call back into Sema if it sees a 10709 // call to such a function. 10710 InstantiateFunctionDefinition(PointOfInstantiation, Func); 10711 else { 10712 PendingInstantiations.push_back(std::make_pair(Func, 10713 PointOfInstantiation)); 10714 // Notify the consumer that a function was implicitly instantiated. 10715 Consumer.HandleCXXImplicitFunctionInstantiation(Func); 10716 } 10717 } 10718 } else { 10719 // Walk redefinitions, as some of them may be instantiable. 10720 for (FunctionDecl::redecl_iterator i(Func->redecls_begin()), 10721 e(Func->redecls_end()); i != e; ++i) { 10722 if (!i->isUsed(false) && i->isImplicitlyInstantiable()) 10723 MarkFunctionReferenced(Loc, *i); 10724 } 10725 } 10726 10727 // Keep track of used but undefined functions. 10728 if (!Func->isDefined()) { 10729 if (mightHaveNonExternalLinkage(Func)) 10730 UndefinedButUsed.insert(std::make_pair(Func->getCanonicalDecl(), Loc)); 10731 else if (Func->getMostRecentDecl()->isInlined() && 10732 (LangOpts.CPlusPlus || !LangOpts.GNUInline) && 10733 !Func->getMostRecentDecl()->hasAttr<GNUInlineAttr>()) 10734 UndefinedButUsed.insert(std::make_pair(Func->getCanonicalDecl(), Loc)); 10735 } 10736 10737 // Normally the must current decl is marked used while processing the use and 10738 // any subsequent decls are marked used by decl merging. This fails with 10739 // template instantiation since marking can happen at the end of the file 10740 // and, because of the two phase lookup, this function is called with at 10741 // decl in the middle of a decl chain. We loop to maintain the invariant 10742 // that once a decl is used, all decls after it are also used. 10743 for (FunctionDecl *F = Func->getMostRecentDecl();; F = F->getPreviousDecl()) { 10744 F->setUsed(true); 10745 if (F == Func) 10746 break; 10747 } 10748} 10749 10750static void 10751diagnoseUncapturableValueReference(Sema &S, SourceLocation loc, 10752 VarDecl *var, DeclContext *DC) { 10753 DeclContext *VarDC = var->getDeclContext(); 10754 10755 // If the parameter still belongs to the translation unit, then 10756 // we're actually just using one parameter in the declaration of 10757 // the next. 10758 if (isa<ParmVarDecl>(var) && 10759 isa<TranslationUnitDecl>(VarDC)) 10760 return; 10761 10762 // For C code, don't diagnose about capture if we're not actually in code 10763 // right now; it's impossible to write a non-constant expression outside of 10764 // function context, so we'll get other (more useful) diagnostics later. 10765 // 10766 // For C++, things get a bit more nasty... it would be nice to suppress this 10767 // diagnostic for certain cases like using a local variable in an array bound 10768 // for a member of a local class, but the correct predicate is not obvious. 10769 if (!S.getLangOpts().CPlusPlus && !S.CurContext->isFunctionOrMethod()) 10770 return; 10771 10772 if (isa<CXXMethodDecl>(VarDC) && 10773 cast<CXXRecordDecl>(VarDC->getParent())->isLambda()) { 10774 S.Diag(loc, diag::err_reference_to_local_var_in_enclosing_lambda) 10775 << var->getIdentifier(); 10776 } else if (FunctionDecl *fn = dyn_cast<FunctionDecl>(VarDC)) { 10777 S.Diag(loc, diag::err_reference_to_local_var_in_enclosing_function) 10778 << var->getIdentifier() << fn->getDeclName(); 10779 } else if (isa<BlockDecl>(VarDC)) { 10780 S.Diag(loc, diag::err_reference_to_local_var_in_enclosing_block) 10781 << var->getIdentifier(); 10782 } else { 10783 // FIXME: Is there any other context where a local variable can be 10784 // declared? 10785 S.Diag(loc, diag::err_reference_to_local_var_in_enclosing_context) 10786 << var->getIdentifier(); 10787 } 10788 10789 S.Diag(var->getLocation(), diag::note_local_variable_declared_here) 10790 << var->getIdentifier(); 10791 10792 // FIXME: Add additional diagnostic info about class etc. which prevents 10793 // capture. 10794} 10795 10796/// \brief Capture the given variable in the given lambda expression. 10797static ExprResult captureInLambda(Sema &S, LambdaScopeInfo *LSI, 10798 VarDecl *Var, QualType FieldType, 10799 QualType DeclRefType, 10800 SourceLocation Loc, 10801 bool RefersToEnclosingLocal) { 10802 CXXRecordDecl *Lambda = LSI->Lambda; 10803 10804 // Build the non-static data member. 10805 FieldDecl *Field 10806 = FieldDecl::Create(S.Context, Lambda, Loc, Loc, 0, FieldType, 10807 S.Context.getTrivialTypeSourceInfo(FieldType, Loc), 10808 0, false, ICIS_NoInit); 10809 Field->setImplicit(true); 10810 Field->setAccess(AS_private); 10811 Lambda->addDecl(Field); 10812 10813 // C++11 [expr.prim.lambda]p21: 10814 // When the lambda-expression is evaluated, the entities that 10815 // are captured by copy are used to direct-initialize each 10816 // corresponding non-static data member of the resulting closure 10817 // object. (For array members, the array elements are 10818 // direct-initialized in increasing subscript order.) These 10819 // initializations are performed in the (unspecified) order in 10820 // which the non-static data members are declared. 10821 10822 // Introduce a new evaluation context for the initialization, so 10823 // that temporaries introduced as part of the capture are retained 10824 // to be re-"exported" from the lambda expression itself. 10825 EnterExpressionEvaluationContext scope(S, Sema::PotentiallyEvaluated); 10826 10827 // C++ [expr.prim.labda]p12: 10828 // An entity captured by a lambda-expression is odr-used (3.2) in 10829 // the scope containing the lambda-expression. 10830 Expr *Ref = new (S.Context) DeclRefExpr(Var, RefersToEnclosingLocal, 10831 DeclRefType, VK_LValue, Loc); 10832 Var->setReferenced(true); 10833 Var->setUsed(true); 10834 10835 // When the field has array type, create index variables for each 10836 // dimension of the array. We use these index variables to subscript 10837 // the source array, and other clients (e.g., CodeGen) will perform 10838 // the necessary iteration with these index variables. 10839 SmallVector<VarDecl *, 4> IndexVariables; 10840 QualType BaseType = FieldType; 10841 QualType SizeType = S.Context.getSizeType(); 10842 LSI->ArrayIndexStarts.push_back(LSI->ArrayIndexVars.size()); 10843 while (const ConstantArrayType *Array 10844 = S.Context.getAsConstantArrayType(BaseType)) { 10845 // Create the iteration variable for this array index. 10846 IdentifierInfo *IterationVarName = 0; 10847 { 10848 SmallString<8> Str; 10849 llvm::raw_svector_ostream OS(Str); 10850 OS << "__i" << IndexVariables.size(); 10851 IterationVarName = &S.Context.Idents.get(OS.str()); 10852 } 10853 VarDecl *IterationVar 10854 = VarDecl::Create(S.Context, S.CurContext, Loc, Loc, 10855 IterationVarName, SizeType, 10856 S.Context.getTrivialTypeSourceInfo(SizeType, Loc), 10857 SC_None); 10858 IndexVariables.push_back(IterationVar); 10859 LSI->ArrayIndexVars.push_back(IterationVar); 10860 10861 // Create a reference to the iteration variable. 10862 ExprResult IterationVarRef 10863 = S.BuildDeclRefExpr(IterationVar, SizeType, VK_LValue, Loc); 10864 assert(!IterationVarRef.isInvalid() && 10865 "Reference to invented variable cannot fail!"); 10866 IterationVarRef = S.DefaultLvalueConversion(IterationVarRef.take()); 10867 assert(!IterationVarRef.isInvalid() && 10868 "Conversion of invented variable cannot fail!"); 10869 10870 // Subscript the array with this iteration variable. 10871 ExprResult Subscript = S.CreateBuiltinArraySubscriptExpr( 10872 Ref, Loc, IterationVarRef.take(), Loc); 10873 if (Subscript.isInvalid()) { 10874 S.CleanupVarDeclMarking(); 10875 S.DiscardCleanupsInEvaluationContext(); 10876 return ExprError(); 10877 } 10878 10879 Ref = Subscript.take(); 10880 BaseType = Array->getElementType(); 10881 } 10882 10883 // Construct the entity that we will be initializing. For an array, this 10884 // will be first element in the array, which may require several levels 10885 // of array-subscript entities. 10886 SmallVector<InitializedEntity, 4> Entities; 10887 Entities.reserve(1 + IndexVariables.size()); 10888 Entities.push_back( 10889 InitializedEntity::InitializeLambdaCapture(Var, Field, Loc)); 10890 for (unsigned I = 0, N = IndexVariables.size(); I != N; ++I) 10891 Entities.push_back(InitializedEntity::InitializeElement(S.Context, 10892 0, 10893 Entities.back())); 10894 10895 InitializationKind InitKind 10896 = InitializationKind::CreateDirect(Loc, Loc, Loc); 10897 InitializationSequence Init(S, Entities.back(), InitKind, &Ref, 1); 10898 ExprResult Result(true); 10899 if (!Init.Diagnose(S, Entities.back(), InitKind, &Ref, 1)) 10900 Result = Init.Perform(S, Entities.back(), InitKind, Ref); 10901 10902 // If this initialization requires any cleanups (e.g., due to a 10903 // default argument to a copy constructor), note that for the 10904 // lambda. 10905 if (S.ExprNeedsCleanups) 10906 LSI->ExprNeedsCleanups = true; 10907 10908 // Exit the expression evaluation context used for the capture. 10909 S.CleanupVarDeclMarking(); 10910 S.DiscardCleanupsInEvaluationContext(); 10911 return Result; 10912} 10913 10914bool Sema::tryCaptureVariable(VarDecl *Var, SourceLocation Loc, 10915 TryCaptureKind Kind, SourceLocation EllipsisLoc, 10916 bool BuildAndDiagnose, 10917 QualType &CaptureType, 10918 QualType &DeclRefType) { 10919 bool Nested = false; 10920 10921 DeclContext *DC = CurContext; 10922 if (Var->getDeclContext() == DC) return true; 10923 if (!Var->hasLocalStorage()) return true; 10924 10925 bool HasBlocksAttr = Var->hasAttr<BlocksAttr>(); 10926 10927 // Walk up the stack to determine whether we can capture the variable, 10928 // performing the "simple" checks that don't depend on type. We stop when 10929 // we've either hit the declared scope of the variable or find an existing 10930 // capture of that variable. 10931 CaptureType = Var->getType(); 10932 DeclRefType = CaptureType.getNonReferenceType(); 10933 bool Explicit = (Kind != TryCapture_Implicit); 10934 unsigned FunctionScopesIndex = FunctionScopes.size() - 1; 10935 do { 10936 // Only block literals and lambda expressions can capture; other 10937 // scopes don't work. 10938 DeclContext *ParentDC; 10939 if (isa<BlockDecl>(DC)) 10940 ParentDC = DC->getParent(); 10941 else if (isa<CXXMethodDecl>(DC) && 10942 cast<CXXMethodDecl>(DC)->getOverloadedOperator() == OO_Call && 10943 cast<CXXRecordDecl>(DC->getParent())->isLambda()) 10944 ParentDC = DC->getParent()->getParent(); 10945 else { 10946 if (BuildAndDiagnose) 10947 diagnoseUncapturableValueReference(*this, Loc, Var, DC); 10948 return true; 10949 } 10950 10951 CapturingScopeInfo *CSI = 10952 cast<CapturingScopeInfo>(FunctionScopes[FunctionScopesIndex]); 10953 10954 // Check whether we've already captured it. 10955 if (CSI->CaptureMap.count(Var)) { 10956 // If we found a capture, any subcaptures are nested. 10957 Nested = true; 10958 10959 // Retrieve the capture type for this variable. 10960 CaptureType = CSI->getCapture(Var).getCaptureType(); 10961 10962 // Compute the type of an expression that refers to this variable. 10963 DeclRefType = CaptureType.getNonReferenceType(); 10964 10965 const CapturingScopeInfo::Capture &Cap = CSI->getCapture(Var); 10966 if (Cap.isCopyCapture() && 10967 !(isa<LambdaScopeInfo>(CSI) && cast<LambdaScopeInfo>(CSI)->Mutable)) 10968 DeclRefType.addConst(); 10969 break; 10970 } 10971 10972 bool IsBlock = isa<BlockScopeInfo>(CSI); 10973 bool IsLambda = !IsBlock; 10974 10975 // Lambdas are not allowed to capture unnamed variables 10976 // (e.g. anonymous unions). 10977 // FIXME: The C++11 rule don't actually state this explicitly, but I'm 10978 // assuming that's the intent. 10979 if (IsLambda && !Var->getDeclName()) { 10980 if (BuildAndDiagnose) { 10981 Diag(Loc, diag::err_lambda_capture_anonymous_var); 10982 Diag(Var->getLocation(), diag::note_declared_at); 10983 } 10984 return true; 10985 } 10986 10987 // Prohibit variably-modified types; they're difficult to deal with. 10988 if (Var->getType()->isVariablyModifiedType()) { 10989 if (BuildAndDiagnose) { 10990 if (IsBlock) 10991 Diag(Loc, diag::err_ref_vm_type); 10992 else 10993 Diag(Loc, diag::err_lambda_capture_vm_type) << Var->getDeclName(); 10994 Diag(Var->getLocation(), diag::note_previous_decl) 10995 << Var->getDeclName(); 10996 } 10997 return true; 10998 } 10999 // Prohibit structs with flexible array members too. 11000 // We cannot capture what is in the tail end of the struct. 11001 if (const RecordType *VTTy = Var->getType()->getAs<RecordType>()) { 11002 if (VTTy->getDecl()->hasFlexibleArrayMember()) { 11003 if (BuildAndDiagnose) { 11004 if (IsBlock) 11005 Diag(Loc, diag::err_ref_flexarray_type); 11006 else 11007 Diag(Loc, diag::err_lambda_capture_flexarray_type) 11008 << Var->getDeclName(); 11009 Diag(Var->getLocation(), diag::note_previous_decl) 11010 << Var->getDeclName(); 11011 } 11012 return true; 11013 } 11014 } 11015 // Lambdas are not allowed to capture __block variables; they don't 11016 // support the expected semantics. 11017 if (IsLambda && HasBlocksAttr) { 11018 if (BuildAndDiagnose) { 11019 Diag(Loc, diag::err_lambda_capture_block) 11020 << Var->getDeclName(); 11021 Diag(Var->getLocation(), diag::note_previous_decl) 11022 << Var->getDeclName(); 11023 } 11024 return true; 11025 } 11026 11027 if (CSI->ImpCaptureStyle == CapturingScopeInfo::ImpCap_None && !Explicit) { 11028 // No capture-default 11029 if (BuildAndDiagnose) { 11030 Diag(Loc, diag::err_lambda_impcap) << Var->getDeclName(); 11031 Diag(Var->getLocation(), diag::note_previous_decl) 11032 << Var->getDeclName(); 11033 Diag(cast<LambdaScopeInfo>(CSI)->Lambda->getLocStart(), 11034 diag::note_lambda_decl); 11035 } 11036 return true; 11037 } 11038 11039 FunctionScopesIndex--; 11040 DC = ParentDC; 11041 Explicit = false; 11042 } while (!Var->getDeclContext()->Equals(DC)); 11043 11044 // Walk back down the scope stack, computing the type of the capture at 11045 // each step, checking type-specific requirements, and adding captures if 11046 // requested. 11047 for (unsigned I = ++FunctionScopesIndex, N = FunctionScopes.size(); I != N; 11048 ++I) { 11049 CapturingScopeInfo *CSI = cast<CapturingScopeInfo>(FunctionScopes[I]); 11050 11051 // Compute the type of the capture and of a reference to the capture within 11052 // this scope. 11053 if (isa<BlockScopeInfo>(CSI)) { 11054 Expr *CopyExpr = 0; 11055 bool ByRef = false; 11056 11057 // Blocks are not allowed to capture arrays. 11058 if (CaptureType->isArrayType()) { 11059 if (BuildAndDiagnose) { 11060 Diag(Loc, diag::err_ref_array_type); 11061 Diag(Var->getLocation(), diag::note_previous_decl) 11062 << Var->getDeclName(); 11063 } 11064 return true; 11065 } 11066 11067 // Forbid the block-capture of autoreleasing variables. 11068 if (CaptureType.getObjCLifetime() == Qualifiers::OCL_Autoreleasing) { 11069 if (BuildAndDiagnose) { 11070 Diag(Loc, diag::err_arc_autoreleasing_capture) 11071 << /*block*/ 0; 11072 Diag(Var->getLocation(), diag::note_previous_decl) 11073 << Var->getDeclName(); 11074 } 11075 return true; 11076 } 11077 11078 if (HasBlocksAttr || CaptureType->isReferenceType()) { 11079 // Block capture by reference does not change the capture or 11080 // declaration reference types. 11081 ByRef = true; 11082 } else { 11083 // Block capture by copy introduces 'const'. 11084 CaptureType = CaptureType.getNonReferenceType().withConst(); 11085 DeclRefType = CaptureType; 11086 11087 if (getLangOpts().CPlusPlus && BuildAndDiagnose) { 11088 if (const RecordType *Record = DeclRefType->getAs<RecordType>()) { 11089 // The capture logic needs the destructor, so make sure we mark it. 11090 // Usually this is unnecessary because most local variables have 11091 // their destructors marked at declaration time, but parameters are 11092 // an exception because it's technically only the call site that 11093 // actually requires the destructor. 11094 if (isa<ParmVarDecl>(Var)) 11095 FinalizeVarWithDestructor(Var, Record); 11096 11097 // Enter a new evaluation context to insulate the copy 11098 // full-expression. 11099 EnterExpressionEvaluationContext scope(*this, PotentiallyEvaluated); 11100 11101 // According to the blocks spec, the capture of a variable from 11102 // the stack requires a const copy constructor. This is not true 11103 // of the copy/move done to move a __block variable to the heap. 11104 Expr *DeclRef = new (Context) DeclRefExpr(Var, Nested, 11105 DeclRefType.withConst(), 11106 VK_LValue, Loc); 11107 11108 ExprResult Result 11109 = PerformCopyInitialization( 11110 InitializedEntity::InitializeBlock(Var->getLocation(), 11111 CaptureType, false), 11112 Loc, Owned(DeclRef)); 11113 11114 // Build a full-expression copy expression if initialization 11115 // succeeded and used a non-trivial constructor. Recover from 11116 // errors by pretending that the copy isn't necessary. 11117 if (!Result.isInvalid() && 11118 !cast<CXXConstructExpr>(Result.get())->getConstructor() 11119 ->isTrivial()) { 11120 Result = MaybeCreateExprWithCleanups(Result); 11121 CopyExpr = Result.take(); 11122 } 11123 } 11124 } 11125 } 11126 11127 // Actually capture the variable. 11128 if (BuildAndDiagnose) 11129 CSI->addCapture(Var, HasBlocksAttr, ByRef, Nested, Loc, 11130 SourceLocation(), CaptureType, CopyExpr); 11131 Nested = true; 11132 continue; 11133 } 11134 11135 LambdaScopeInfo *LSI = cast<LambdaScopeInfo>(CSI); 11136 11137 // Determine whether we are capturing by reference or by value. 11138 bool ByRef = false; 11139 if (I == N - 1 && Kind != TryCapture_Implicit) { 11140 ByRef = (Kind == TryCapture_ExplicitByRef); 11141 } else { 11142 ByRef = (LSI->ImpCaptureStyle == LambdaScopeInfo::ImpCap_LambdaByref); 11143 } 11144 11145 // Compute the type of the field that will capture this variable. 11146 if (ByRef) { 11147 // C++11 [expr.prim.lambda]p15: 11148 // An entity is captured by reference if it is implicitly or 11149 // explicitly captured but not captured by copy. It is 11150 // unspecified whether additional unnamed non-static data 11151 // members are declared in the closure type for entities 11152 // captured by reference. 11153 // 11154 // FIXME: It is not clear whether we want to build an lvalue reference 11155 // to the DeclRefType or to CaptureType.getNonReferenceType(). GCC appears 11156 // to do the former, while EDG does the latter. Core issue 1249 will 11157 // clarify, but for now we follow GCC because it's a more permissive and 11158 // easily defensible position. 11159 CaptureType = Context.getLValueReferenceType(DeclRefType); 11160 } else { 11161 // C++11 [expr.prim.lambda]p14: 11162 // For each entity captured by copy, an unnamed non-static 11163 // data member is declared in the closure type. The 11164 // declaration order of these members is unspecified. The type 11165 // of such a data member is the type of the corresponding 11166 // captured entity if the entity is not a reference to an 11167 // object, or the referenced type otherwise. [Note: If the 11168 // captured entity is a reference to a function, the 11169 // corresponding data member is also a reference to a 11170 // function. - end note ] 11171 if (const ReferenceType *RefType = CaptureType->getAs<ReferenceType>()){ 11172 if (!RefType->getPointeeType()->isFunctionType()) 11173 CaptureType = RefType->getPointeeType(); 11174 } 11175 11176 // Forbid the lambda copy-capture of autoreleasing variables. 11177 if (CaptureType.getObjCLifetime() == Qualifiers::OCL_Autoreleasing) { 11178 if (BuildAndDiagnose) { 11179 Diag(Loc, diag::err_arc_autoreleasing_capture) << /*lambda*/ 1; 11180 Diag(Var->getLocation(), diag::note_previous_decl) 11181 << Var->getDeclName(); 11182 } 11183 return true; 11184 } 11185 } 11186 11187 // Capture this variable in the lambda. 11188 Expr *CopyExpr = 0; 11189 if (BuildAndDiagnose) { 11190 ExprResult Result = captureInLambda(*this, LSI, Var, CaptureType, 11191 DeclRefType, Loc, 11192 Nested); 11193 if (!Result.isInvalid()) 11194 CopyExpr = Result.take(); 11195 } 11196 11197 // Compute the type of a reference to this captured variable. 11198 if (ByRef) 11199 DeclRefType = CaptureType.getNonReferenceType(); 11200 else { 11201 // C++ [expr.prim.lambda]p5: 11202 // The closure type for a lambda-expression has a public inline 11203 // function call operator [...]. This function call operator is 11204 // declared const (9.3.1) if and only if the lambda-expression’s 11205 // parameter-declaration-clause is not followed by mutable. 11206 DeclRefType = CaptureType.getNonReferenceType(); 11207 if (!LSI->Mutable && !CaptureType->isReferenceType()) 11208 DeclRefType.addConst(); 11209 } 11210 11211 // Add the capture. 11212 if (BuildAndDiagnose) 11213 CSI->addCapture(Var, /*IsBlock=*/false, ByRef, Nested, Loc, 11214 EllipsisLoc, CaptureType, CopyExpr); 11215 Nested = true; 11216 } 11217 11218 return false; 11219} 11220 11221bool Sema::tryCaptureVariable(VarDecl *Var, SourceLocation Loc, 11222 TryCaptureKind Kind, SourceLocation EllipsisLoc) { 11223 QualType CaptureType; 11224 QualType DeclRefType; 11225 return tryCaptureVariable(Var, Loc, Kind, EllipsisLoc, 11226 /*BuildAndDiagnose=*/true, CaptureType, 11227 DeclRefType); 11228} 11229 11230QualType Sema::getCapturedDeclRefType(VarDecl *Var, SourceLocation Loc) { 11231 QualType CaptureType; 11232 QualType DeclRefType; 11233 11234 // Determine whether we can capture this variable. 11235 if (tryCaptureVariable(Var, Loc, TryCapture_Implicit, SourceLocation(), 11236 /*BuildAndDiagnose=*/false, CaptureType, DeclRefType)) 11237 return QualType(); 11238 11239 return DeclRefType; 11240} 11241 11242static void MarkVarDeclODRUsed(Sema &SemaRef, VarDecl *Var, 11243 SourceLocation Loc) { 11244 // Keep track of used but undefined variables. 11245 // FIXME: We shouldn't suppress this warning for static data members. 11246 if (Var->hasDefinition(SemaRef.Context) == VarDecl::DeclarationOnly && 11247 Var->getLinkage() != ExternalLinkage && 11248 !(Var->isStaticDataMember() && Var->hasInit())) { 11249 SourceLocation &old = SemaRef.UndefinedButUsed[Var->getCanonicalDecl()]; 11250 if (old.isInvalid()) old = Loc; 11251 } 11252 11253 SemaRef.tryCaptureVariable(Var, Loc); 11254 11255 Var->setUsed(true); 11256} 11257 11258void Sema::UpdateMarkingForLValueToRValue(Expr *E) { 11259 // Per C++11 [basic.def.odr], a variable is odr-used "unless it is 11260 // an object that satisfies the requirements for appearing in a 11261 // constant expression (5.19) and the lvalue-to-rvalue conversion (4.1) 11262 // is immediately applied." This function handles the lvalue-to-rvalue 11263 // conversion part. 11264 MaybeODRUseExprs.erase(E->IgnoreParens()); 11265} 11266 11267ExprResult Sema::ActOnConstantExpression(ExprResult Res) { 11268 if (!Res.isUsable()) 11269 return Res; 11270 11271 // If a constant-expression is a reference to a variable where we delay 11272 // deciding whether it is an odr-use, just assume we will apply the 11273 // lvalue-to-rvalue conversion. In the one case where this doesn't happen 11274 // (a non-type template argument), we have special handling anyway. 11275 UpdateMarkingForLValueToRValue(Res.get()); 11276 return Res; 11277} 11278 11279void Sema::CleanupVarDeclMarking() { 11280 for (llvm::SmallPtrSetIterator<Expr*> i = MaybeODRUseExprs.begin(), 11281 e = MaybeODRUseExprs.end(); 11282 i != e; ++i) { 11283 VarDecl *Var; 11284 SourceLocation Loc; 11285 if (DeclRefExpr *DRE = dyn_cast<DeclRefExpr>(*i)) { 11286 Var = cast<VarDecl>(DRE->getDecl()); 11287 Loc = DRE->getLocation(); 11288 } else if (MemberExpr *ME = dyn_cast<MemberExpr>(*i)) { 11289 Var = cast<VarDecl>(ME->getMemberDecl()); 11290 Loc = ME->getMemberLoc(); 11291 } else { 11292 llvm_unreachable("Unexpcted expression"); 11293 } 11294 11295 MarkVarDeclODRUsed(*this, Var, Loc); 11296 } 11297 11298 MaybeODRUseExprs.clear(); 11299} 11300 11301// Mark a VarDecl referenced, and perform the necessary handling to compute 11302// odr-uses. 11303static void DoMarkVarDeclReferenced(Sema &SemaRef, SourceLocation Loc, 11304 VarDecl *Var, Expr *E) { 11305 Var->setReferenced(); 11306 11307 if (!IsPotentiallyEvaluatedContext(SemaRef)) 11308 return; 11309 11310 // Implicit instantiation of static data members of class templates. 11311 if (Var->isStaticDataMember() && Var->getInstantiatedFromStaticDataMember()) { 11312 MemberSpecializationInfo *MSInfo = Var->getMemberSpecializationInfo(); 11313 assert(MSInfo && "Missing member specialization information?"); 11314 bool AlreadyInstantiated = !MSInfo->getPointOfInstantiation().isInvalid(); 11315 if (MSInfo->getTemplateSpecializationKind() == TSK_ImplicitInstantiation && 11316 (!AlreadyInstantiated || 11317 Var->isUsableInConstantExpressions(SemaRef.Context))) { 11318 if (!AlreadyInstantiated) { 11319 // This is a modification of an existing AST node. Notify listeners. 11320 if (ASTMutationListener *L = SemaRef.getASTMutationListener()) 11321 L->StaticDataMemberInstantiated(Var); 11322 MSInfo->setPointOfInstantiation(Loc); 11323 } 11324 SourceLocation PointOfInstantiation = MSInfo->getPointOfInstantiation(); 11325 if (Var->isUsableInConstantExpressions(SemaRef.Context)) 11326 // Do not defer instantiations of variables which could be used in a 11327 // constant expression. 11328 SemaRef.InstantiateStaticDataMemberDefinition(PointOfInstantiation,Var); 11329 else 11330 SemaRef.PendingInstantiations.push_back( 11331 std::make_pair(Var, PointOfInstantiation)); 11332 } 11333 } 11334 11335 // Per C++11 [basic.def.odr], a variable is odr-used "unless it satisfies 11336 // the requirements for appearing in a constant expression (5.19) and, if 11337 // it is an object, the lvalue-to-rvalue conversion (4.1) 11338 // is immediately applied." We check the first part here, and 11339 // Sema::UpdateMarkingForLValueToRValue deals with the second part. 11340 // Note that we use the C++11 definition everywhere because nothing in 11341 // C++03 depends on whether we get the C++03 version correct. The second 11342 // part does not apply to references, since they are not objects. 11343 const VarDecl *DefVD; 11344 if (E && !isa<ParmVarDecl>(Var) && 11345 Var->isUsableInConstantExpressions(SemaRef.Context) && 11346 Var->getAnyInitializer(DefVD) && DefVD->checkInitIsICE()) { 11347 if (!Var->getType()->isReferenceType()) 11348 SemaRef.MaybeODRUseExprs.insert(E); 11349 } else 11350 MarkVarDeclODRUsed(SemaRef, Var, Loc); 11351} 11352 11353/// \brief Mark a variable referenced, and check whether it is odr-used 11354/// (C++ [basic.def.odr]p2, C99 6.9p3). Note that this should not be 11355/// used directly for normal expressions referring to VarDecl. 11356void Sema::MarkVariableReferenced(SourceLocation Loc, VarDecl *Var) { 11357 DoMarkVarDeclReferenced(*this, Loc, Var, 0); 11358} 11359 11360static void MarkExprReferenced(Sema &SemaRef, SourceLocation Loc, 11361 Decl *D, Expr *E, bool OdrUse) { 11362 if (VarDecl *Var = dyn_cast<VarDecl>(D)) { 11363 DoMarkVarDeclReferenced(SemaRef, Loc, Var, E); 11364 return; 11365 } 11366 11367 SemaRef.MarkAnyDeclReferenced(Loc, D, OdrUse); 11368 11369 // If this is a call to a method via a cast, also mark the method in the 11370 // derived class used in case codegen can devirtualize the call. 11371 const MemberExpr *ME = dyn_cast<MemberExpr>(E); 11372 if (!ME) 11373 return; 11374 CXXMethodDecl *MD = dyn_cast<CXXMethodDecl>(ME->getMemberDecl()); 11375 if (!MD) 11376 return; 11377 const Expr *Base = ME->getBase(); 11378 const CXXRecordDecl *MostDerivedClassDecl = Base->getBestDynamicClassType(); 11379 if (!MostDerivedClassDecl) 11380 return; 11381 CXXMethodDecl *DM = MD->getCorrespondingMethodInClass(MostDerivedClassDecl); 11382 if (!DM || DM->isPure()) 11383 return; 11384 SemaRef.MarkAnyDeclReferenced(Loc, DM, OdrUse); 11385} 11386 11387/// \brief Perform reference-marking and odr-use handling for a DeclRefExpr. 11388void Sema::MarkDeclRefReferenced(DeclRefExpr *E) { 11389 // TODO: update this with DR# once a defect report is filed. 11390 // C++11 defect. The address of a pure member should not be an ODR use, even 11391 // if it's a qualified reference. 11392 bool OdrUse = true; 11393 if (CXXMethodDecl *Method = dyn_cast<CXXMethodDecl>(E->getDecl())) 11394 if (Method->isVirtual()) 11395 OdrUse = false; 11396 MarkExprReferenced(*this, E->getLocation(), E->getDecl(), E, OdrUse); 11397} 11398 11399/// \brief Perform reference-marking and odr-use handling for a MemberExpr. 11400void Sema::MarkMemberReferenced(MemberExpr *E) { 11401 // C++11 [basic.def.odr]p2: 11402 // A non-overloaded function whose name appears as a potentially-evaluated 11403 // expression or a member of a set of candidate functions, if selected by 11404 // overload resolution when referred to from a potentially-evaluated 11405 // expression, is odr-used, unless it is a pure virtual function and its 11406 // name is not explicitly qualified. 11407 bool OdrUse = true; 11408 if (!E->hasQualifier()) { 11409 if (CXXMethodDecl *Method = dyn_cast<CXXMethodDecl>(E->getMemberDecl())) 11410 if (Method->isPure()) 11411 OdrUse = false; 11412 } 11413 SourceLocation Loc = E->getMemberLoc().isValid() ? 11414 E->getMemberLoc() : E->getLocStart(); 11415 MarkExprReferenced(*this, Loc, E->getMemberDecl(), E, OdrUse); 11416} 11417 11418/// \brief Perform marking for a reference to an arbitrary declaration. It 11419/// marks the declaration referenced, and performs odr-use checking for functions 11420/// and variables. This method should not be used when building an normal 11421/// expression which refers to a variable. 11422void Sema::MarkAnyDeclReferenced(SourceLocation Loc, Decl *D, bool OdrUse) { 11423 if (OdrUse) { 11424 if (VarDecl *VD = dyn_cast<VarDecl>(D)) { 11425 MarkVariableReferenced(Loc, VD); 11426 return; 11427 } 11428 if (FunctionDecl *FD = dyn_cast<FunctionDecl>(D)) { 11429 MarkFunctionReferenced(Loc, FD); 11430 return; 11431 } 11432 } 11433 D->setReferenced(); 11434} 11435 11436namespace { 11437 // Mark all of the declarations referenced 11438 // FIXME: Not fully implemented yet! We need to have a better understanding 11439 // of when we're entering 11440 class MarkReferencedDecls : public RecursiveASTVisitor<MarkReferencedDecls> { 11441 Sema &S; 11442 SourceLocation Loc; 11443 11444 public: 11445 typedef RecursiveASTVisitor<MarkReferencedDecls> Inherited; 11446 11447 MarkReferencedDecls(Sema &S, SourceLocation Loc) : S(S), Loc(Loc) { } 11448 11449 bool TraverseTemplateArgument(const TemplateArgument &Arg); 11450 bool TraverseRecordType(RecordType *T); 11451 }; 11452} 11453 11454bool MarkReferencedDecls::TraverseTemplateArgument( 11455 const TemplateArgument &Arg) { 11456 if (Arg.getKind() == TemplateArgument::Declaration) { 11457 if (Decl *D = Arg.getAsDecl()) 11458 S.MarkAnyDeclReferenced(Loc, D, true); 11459 } 11460 11461 return Inherited::TraverseTemplateArgument(Arg); 11462} 11463 11464bool MarkReferencedDecls::TraverseRecordType(RecordType *T) { 11465 if (ClassTemplateSpecializationDecl *Spec 11466 = dyn_cast<ClassTemplateSpecializationDecl>(T->getDecl())) { 11467 const TemplateArgumentList &Args = Spec->getTemplateArgs(); 11468 return TraverseTemplateArguments(Args.data(), Args.size()); 11469 } 11470 11471 return true; 11472} 11473 11474void Sema::MarkDeclarationsReferencedInType(SourceLocation Loc, QualType T) { 11475 MarkReferencedDecls Marker(*this, Loc); 11476 Marker.TraverseType(Context.getCanonicalType(T)); 11477} 11478 11479namespace { 11480 /// \brief Helper class that marks all of the declarations referenced by 11481 /// potentially-evaluated subexpressions as "referenced". 11482 class EvaluatedExprMarker : public EvaluatedExprVisitor<EvaluatedExprMarker> { 11483 Sema &S; 11484 bool SkipLocalVariables; 11485 11486 public: 11487 typedef EvaluatedExprVisitor<EvaluatedExprMarker> Inherited; 11488 11489 EvaluatedExprMarker(Sema &S, bool SkipLocalVariables) 11490 : Inherited(S.Context), S(S), SkipLocalVariables(SkipLocalVariables) { } 11491 11492 void VisitDeclRefExpr(DeclRefExpr *E) { 11493 // If we were asked not to visit local variables, don't. 11494 if (SkipLocalVariables) { 11495 if (VarDecl *VD = dyn_cast<VarDecl>(E->getDecl())) 11496 if (VD->hasLocalStorage()) 11497 return; 11498 } 11499 11500 S.MarkDeclRefReferenced(E); 11501 } 11502 11503 void VisitMemberExpr(MemberExpr *E) { 11504 S.MarkMemberReferenced(E); 11505 Inherited::VisitMemberExpr(E); 11506 } 11507 11508 void VisitCXXBindTemporaryExpr(CXXBindTemporaryExpr *E) { 11509 S.MarkFunctionReferenced(E->getLocStart(), 11510 const_cast<CXXDestructorDecl*>(E->getTemporary()->getDestructor())); 11511 Visit(E->getSubExpr()); 11512 } 11513 11514 void VisitCXXNewExpr(CXXNewExpr *E) { 11515 if (E->getOperatorNew()) 11516 S.MarkFunctionReferenced(E->getLocStart(), E->getOperatorNew()); 11517 if (E->getOperatorDelete()) 11518 S.MarkFunctionReferenced(E->getLocStart(), E->getOperatorDelete()); 11519 Inherited::VisitCXXNewExpr(E); 11520 } 11521 11522 void VisitCXXDeleteExpr(CXXDeleteExpr *E) { 11523 if (E->getOperatorDelete()) 11524 S.MarkFunctionReferenced(E->getLocStart(), E->getOperatorDelete()); 11525 QualType Destroyed = S.Context.getBaseElementType(E->getDestroyedType()); 11526 if (const RecordType *DestroyedRec = Destroyed->getAs<RecordType>()) { 11527 CXXRecordDecl *Record = cast<CXXRecordDecl>(DestroyedRec->getDecl()); 11528 S.MarkFunctionReferenced(E->getLocStart(), 11529 S.LookupDestructor(Record)); 11530 } 11531 11532 Inherited::VisitCXXDeleteExpr(E); 11533 } 11534 11535 void VisitCXXConstructExpr(CXXConstructExpr *E) { 11536 S.MarkFunctionReferenced(E->getLocStart(), E->getConstructor()); 11537 Inherited::VisitCXXConstructExpr(E); 11538 } 11539 11540 void VisitCXXDefaultArgExpr(CXXDefaultArgExpr *E) { 11541 Visit(E->getExpr()); 11542 } 11543 11544 void VisitImplicitCastExpr(ImplicitCastExpr *E) { 11545 Inherited::VisitImplicitCastExpr(E); 11546 11547 if (E->getCastKind() == CK_LValueToRValue) 11548 S.UpdateMarkingForLValueToRValue(E->getSubExpr()); 11549 } 11550 }; 11551} 11552 11553/// \brief Mark any declarations that appear within this expression or any 11554/// potentially-evaluated subexpressions as "referenced". 11555/// 11556/// \param SkipLocalVariables If true, don't mark local variables as 11557/// 'referenced'. 11558void Sema::MarkDeclarationsReferencedInExpr(Expr *E, 11559 bool SkipLocalVariables) { 11560 EvaluatedExprMarker(*this, SkipLocalVariables).Visit(E); 11561} 11562 11563/// \brief Emit a diagnostic that describes an effect on the run-time behavior 11564/// of the program being compiled. 11565/// 11566/// This routine emits the given diagnostic when the code currently being 11567/// type-checked is "potentially evaluated", meaning that there is a 11568/// possibility that the code will actually be executable. Code in sizeof() 11569/// expressions, code used only during overload resolution, etc., are not 11570/// potentially evaluated. This routine will suppress such diagnostics or, 11571/// in the absolutely nutty case of potentially potentially evaluated 11572/// expressions (C++ typeid), queue the diagnostic to potentially emit it 11573/// later. 11574/// 11575/// This routine should be used for all diagnostics that describe the run-time 11576/// behavior of a program, such as passing a non-POD value through an ellipsis. 11577/// Failure to do so will likely result in spurious diagnostics or failures 11578/// during overload resolution or within sizeof/alignof/typeof/typeid. 11579bool Sema::DiagRuntimeBehavior(SourceLocation Loc, const Stmt *Statement, 11580 const PartialDiagnostic &PD) { 11581 switch (ExprEvalContexts.back().Context) { 11582 case Unevaluated: 11583 // The argument will never be evaluated, so don't complain. 11584 break; 11585 11586 case ConstantEvaluated: 11587 // Relevant diagnostics should be produced by constant evaluation. 11588 break; 11589 11590 case PotentiallyEvaluated: 11591 case PotentiallyEvaluatedIfUsed: 11592 if (Statement && getCurFunctionOrMethodDecl()) { 11593 FunctionScopes.back()->PossiblyUnreachableDiags. 11594 push_back(sema::PossiblyUnreachableDiag(PD, Loc, Statement)); 11595 } 11596 else 11597 Diag(Loc, PD); 11598 11599 return true; 11600 } 11601 11602 return false; 11603} 11604 11605bool Sema::CheckCallReturnType(QualType ReturnType, SourceLocation Loc, 11606 CallExpr *CE, FunctionDecl *FD) { 11607 if (ReturnType->isVoidType() || !ReturnType->isIncompleteType()) 11608 return false; 11609 11610 // If we're inside a decltype's expression, don't check for a valid return 11611 // type or construct temporaries until we know whether this is the last call. 11612 if (ExprEvalContexts.back().IsDecltype) { 11613 ExprEvalContexts.back().DelayedDecltypeCalls.push_back(CE); 11614 return false; 11615 } 11616 11617 class CallReturnIncompleteDiagnoser : public TypeDiagnoser { 11618 FunctionDecl *FD; 11619 CallExpr *CE; 11620 11621 public: 11622 CallReturnIncompleteDiagnoser(FunctionDecl *FD, CallExpr *CE) 11623 : FD(FD), CE(CE) { } 11624 11625 virtual void diagnose(Sema &S, SourceLocation Loc, QualType T) { 11626 if (!FD) { 11627 S.Diag(Loc, diag::err_call_incomplete_return) 11628 << T << CE->getSourceRange(); 11629 return; 11630 } 11631 11632 S.Diag(Loc, diag::err_call_function_incomplete_return) 11633 << CE->getSourceRange() << FD->getDeclName() << T; 11634 S.Diag(FD->getLocation(), 11635 diag::note_function_with_incomplete_return_type_declared_here) 11636 << FD->getDeclName(); 11637 } 11638 } Diagnoser(FD, CE); 11639 11640 if (RequireCompleteType(Loc, ReturnType, Diagnoser)) 11641 return true; 11642 11643 return false; 11644} 11645 11646// Diagnose the s/=/==/ and s/\|=/!=/ typos. Note that adding parentheses 11647// will prevent this condition from triggering, which is what we want. 11648void Sema::DiagnoseAssignmentAsCondition(Expr *E) { 11649 SourceLocation Loc; 11650 11651 unsigned diagnostic = diag::warn_condition_is_assignment; 11652 bool IsOrAssign = false; 11653 11654 if (BinaryOperator *Op = dyn_cast<BinaryOperator>(E)) { 11655 if (Op->getOpcode() != BO_Assign && Op->getOpcode() != BO_OrAssign) 11656 return; 11657 11658 IsOrAssign = Op->getOpcode() == BO_OrAssign; 11659 11660 // Greylist some idioms by putting them into a warning subcategory. 11661 if (ObjCMessageExpr *ME 11662 = dyn_cast<ObjCMessageExpr>(Op->getRHS()->IgnoreParenCasts())) { 11663 Selector Sel = ME->getSelector(); 11664 11665 // self = [<foo> init...] 11666 if (isSelfExpr(Op->getLHS()) && Sel.getNameForSlot(0).startswith("init")) 11667 diagnostic = diag::warn_condition_is_idiomatic_assignment; 11668 11669 // <foo> = [<bar> nextObject] 11670 else if (Sel.isUnarySelector() && Sel.getNameForSlot(0) == "nextObject") 11671 diagnostic = diag::warn_condition_is_idiomatic_assignment; 11672 } 11673 11674 Loc = Op->getOperatorLoc(); 11675 } else if (CXXOperatorCallExpr *Op = dyn_cast<CXXOperatorCallExpr>(E)) { 11676 if (Op->getOperator() != OO_Equal && Op->getOperator() != OO_PipeEqual) 11677 return; 11678 11679 IsOrAssign = Op->getOperator() == OO_PipeEqual; 11680 Loc = Op->getOperatorLoc(); 11681 } else if (PseudoObjectExpr *POE = dyn_cast<PseudoObjectExpr>(E)) 11682 return DiagnoseAssignmentAsCondition(POE->getSyntacticForm()); 11683 else { 11684 // Not an assignment. 11685 return; 11686 } 11687 11688 Diag(Loc, diagnostic) << E->getSourceRange(); 11689 11690 SourceLocation Open = E->getLocStart(); 11691 SourceLocation Close = PP.getLocForEndOfToken(E->getSourceRange().getEnd()); 11692 Diag(Loc, diag::note_condition_assign_silence) 11693 << FixItHint::CreateInsertion(Open, "(") 11694 << FixItHint::CreateInsertion(Close, ")"); 11695 11696 if (IsOrAssign) 11697 Diag(Loc, diag::note_condition_or_assign_to_comparison) 11698 << FixItHint::CreateReplacement(Loc, "!="); 11699 else 11700 Diag(Loc, diag::note_condition_assign_to_comparison) 11701 << FixItHint::CreateReplacement(Loc, "=="); 11702} 11703 11704/// \brief Redundant parentheses over an equality comparison can indicate 11705/// that the user intended an assignment used as condition. 11706void Sema::DiagnoseEqualityWithExtraParens(ParenExpr *ParenE) { 11707 // Don't warn if the parens came from a macro. 11708 SourceLocation parenLoc = ParenE->getLocStart(); 11709 if (parenLoc.isInvalid() || parenLoc.isMacroID()) 11710 return; 11711 // Don't warn for dependent expressions. 11712 if (ParenE->isTypeDependent()) 11713 return; 11714 11715 Expr *E = ParenE->IgnoreParens(); 11716 11717 if (BinaryOperator *opE = dyn_cast<BinaryOperator>(E)) 11718 if (opE->getOpcode() == BO_EQ && 11719 opE->getLHS()->IgnoreParenImpCasts()->isModifiableLvalue(Context) 11720 == Expr::MLV_Valid) { 11721 SourceLocation Loc = opE->getOperatorLoc(); 11722 11723 Diag(Loc, diag::warn_equality_with_extra_parens) << E->getSourceRange(); 11724 SourceRange ParenERange = ParenE->getSourceRange(); 11725 Diag(Loc, diag::note_equality_comparison_silence) 11726 << FixItHint::CreateRemoval(ParenERange.getBegin()) 11727 << FixItHint::CreateRemoval(ParenERange.getEnd()); 11728 Diag(Loc, diag::note_equality_comparison_to_assign) 11729 << FixItHint::CreateReplacement(Loc, "="); 11730 } 11731} 11732 11733ExprResult Sema::CheckBooleanCondition(Expr *E, SourceLocation Loc) { 11734 DiagnoseAssignmentAsCondition(E); 11735 if (ParenExpr *parenE = dyn_cast<ParenExpr>(E)) 11736 DiagnoseEqualityWithExtraParens(parenE); 11737 11738 ExprResult result = CheckPlaceholderExpr(E); 11739 if (result.isInvalid()) return ExprError(); 11740 E = result.take(); 11741 11742 if (!E->isTypeDependent()) { 11743 if (getLangOpts().CPlusPlus) 11744 return CheckCXXBooleanCondition(E); // C++ 6.4p4 11745 11746 ExprResult ERes = DefaultFunctionArrayLvalueConversion(E); 11747 if (ERes.isInvalid()) 11748 return ExprError(); 11749 E = ERes.take(); 11750 11751 QualType T = E->getType(); 11752 if (!T->isScalarType()) { // C99 6.8.4.1p1 11753 Diag(Loc, diag::err_typecheck_statement_requires_scalar) 11754 << T << E->getSourceRange(); 11755 return ExprError(); 11756 } 11757 } 11758 11759 return Owned(E); 11760} 11761 11762ExprResult Sema::ActOnBooleanCondition(Scope *S, SourceLocation Loc, 11763 Expr *SubExpr) { 11764 if (!SubExpr) 11765 return ExprError(); 11766 11767 return CheckBooleanCondition(SubExpr, Loc); 11768} 11769 11770namespace { 11771 /// A visitor for rebuilding a call to an __unknown_any expression 11772 /// to have an appropriate type. 11773 struct RebuildUnknownAnyFunction 11774 : StmtVisitor<RebuildUnknownAnyFunction, ExprResult> { 11775 11776 Sema &S; 11777 11778 RebuildUnknownAnyFunction(Sema &S) : S(S) {} 11779 11780 ExprResult VisitStmt(Stmt *S) { 11781 llvm_unreachable("unexpected statement!"); 11782 } 11783 11784 ExprResult VisitExpr(Expr *E) { 11785 S.Diag(E->getExprLoc(), diag::err_unsupported_unknown_any_call) 11786 << E->getSourceRange(); 11787 return ExprError(); 11788 } 11789 11790 /// Rebuild an expression which simply semantically wraps another 11791 /// expression which it shares the type and value kind of. 11792 template <class T> ExprResult rebuildSugarExpr(T *E) { 11793 ExprResult SubResult = Visit(E->getSubExpr()); 11794 if (SubResult.isInvalid()) return ExprError(); 11795 11796 Expr *SubExpr = SubResult.take(); 11797 E->setSubExpr(SubExpr); 11798 E->setType(SubExpr->getType()); 11799 E->setValueKind(SubExpr->getValueKind()); 11800 assert(E->getObjectKind() == OK_Ordinary); 11801 return E; 11802 } 11803 11804 ExprResult VisitParenExpr(ParenExpr *E) { 11805 return rebuildSugarExpr(E); 11806 } 11807 11808 ExprResult VisitUnaryExtension(UnaryOperator *E) { 11809 return rebuildSugarExpr(E); 11810 } 11811 11812 ExprResult VisitUnaryAddrOf(UnaryOperator *E) { 11813 ExprResult SubResult = Visit(E->getSubExpr()); 11814 if (SubResult.isInvalid()) return ExprError(); 11815 11816 Expr *SubExpr = SubResult.take(); 11817 E->setSubExpr(SubExpr); 11818 E->setType(S.Context.getPointerType(SubExpr->getType())); 11819 assert(E->getValueKind() == VK_RValue); 11820 assert(E->getObjectKind() == OK_Ordinary); 11821 return E; 11822 } 11823 11824 ExprResult resolveDecl(Expr *E, ValueDecl *VD) { 11825 if (!isa<FunctionDecl>(VD)) return VisitExpr(E); 11826 11827 E->setType(VD->getType()); 11828 11829 assert(E->getValueKind() == VK_RValue); 11830 if (S.getLangOpts().CPlusPlus && 11831 !(isa<CXXMethodDecl>(VD) && 11832 cast<CXXMethodDecl>(VD)->isInstance())) 11833 E->setValueKind(VK_LValue); 11834 11835 return E; 11836 } 11837 11838 ExprResult VisitMemberExpr(MemberExpr *E) { 11839 return resolveDecl(E, E->getMemberDecl()); 11840 } 11841 11842 ExprResult VisitDeclRefExpr(DeclRefExpr *E) { 11843 return resolveDecl(E, E->getDecl()); 11844 } 11845 }; 11846} 11847 11848/// Given a function expression of unknown-any type, try to rebuild it 11849/// to have a function type. 11850static ExprResult rebuildUnknownAnyFunction(Sema &S, Expr *FunctionExpr) { 11851 ExprResult Result = RebuildUnknownAnyFunction(S).Visit(FunctionExpr); 11852 if (Result.isInvalid()) return ExprError(); 11853 return S.DefaultFunctionArrayConversion(Result.take()); 11854} 11855 11856namespace { 11857 /// A visitor for rebuilding an expression of type __unknown_anytype 11858 /// into one which resolves the type directly on the referring 11859 /// expression. Strict preservation of the original source 11860 /// structure is not a goal. 11861 struct RebuildUnknownAnyExpr 11862 : StmtVisitor<RebuildUnknownAnyExpr, ExprResult> { 11863 11864 Sema &S; 11865 11866 /// The current destination type. 11867 QualType DestType; 11868 11869 RebuildUnknownAnyExpr(Sema &S, QualType CastType) 11870 : S(S), DestType(CastType) {} 11871 11872 ExprResult VisitStmt(Stmt *S) { 11873 llvm_unreachable("unexpected statement!"); 11874 } 11875 11876 ExprResult VisitExpr(Expr *E) { 11877 S.Diag(E->getExprLoc(), diag::err_unsupported_unknown_any_expr) 11878 << E->getSourceRange(); 11879 return ExprError(); 11880 } 11881 11882 ExprResult VisitCallExpr(CallExpr *E); 11883 ExprResult VisitObjCMessageExpr(ObjCMessageExpr *E); 11884 11885 /// Rebuild an expression which simply semantically wraps another 11886 /// expression which it shares the type and value kind of. 11887 template <class T> ExprResult rebuildSugarExpr(T *E) { 11888 ExprResult SubResult = Visit(E->getSubExpr()); 11889 if (SubResult.isInvalid()) return ExprError(); 11890 Expr *SubExpr = SubResult.take(); 11891 E->setSubExpr(SubExpr); 11892 E->setType(SubExpr->getType()); 11893 E->setValueKind(SubExpr->getValueKind()); 11894 assert(E->getObjectKind() == OK_Ordinary); 11895 return E; 11896 } 11897 11898 ExprResult VisitParenExpr(ParenExpr *E) { 11899 return rebuildSugarExpr(E); 11900 } 11901 11902 ExprResult VisitUnaryExtension(UnaryOperator *E) { 11903 return rebuildSugarExpr(E); 11904 } 11905 11906 ExprResult VisitUnaryAddrOf(UnaryOperator *E) { 11907 const PointerType *Ptr = DestType->getAs<PointerType>(); 11908 if (!Ptr) { 11909 S.Diag(E->getOperatorLoc(), diag::err_unknown_any_addrof) 11910 << E->getSourceRange(); 11911 return ExprError(); 11912 } 11913 assert(E->getValueKind() == VK_RValue); 11914 assert(E->getObjectKind() == OK_Ordinary); 11915 E->setType(DestType); 11916 11917 // Build the sub-expression as if it were an object of the pointee type. 11918 DestType = Ptr->getPointeeType(); 11919 ExprResult SubResult = Visit(E->getSubExpr()); 11920 if (SubResult.isInvalid()) return ExprError(); 11921 E->setSubExpr(SubResult.take()); 11922 return E; 11923 } 11924 11925 ExprResult VisitImplicitCastExpr(ImplicitCastExpr *E); 11926 11927 ExprResult resolveDecl(Expr *E, ValueDecl *VD); 11928 11929 ExprResult VisitMemberExpr(MemberExpr *E) { 11930 return resolveDecl(E, E->getMemberDecl()); 11931 } 11932 11933 ExprResult VisitDeclRefExpr(DeclRefExpr *E) { 11934 return resolveDecl(E, E->getDecl()); 11935 } 11936 }; 11937} 11938 11939/// Rebuilds a call expression which yielded __unknown_anytype. 11940ExprResult RebuildUnknownAnyExpr::VisitCallExpr(CallExpr *E) { 11941 Expr *CalleeExpr = E->getCallee(); 11942 11943 enum FnKind { 11944 FK_MemberFunction, 11945 FK_FunctionPointer, 11946 FK_BlockPointer 11947 }; 11948 11949 FnKind Kind; 11950 QualType CalleeType = CalleeExpr->getType(); 11951 if (CalleeType == S.Context.BoundMemberTy) { 11952 assert(isa<CXXMemberCallExpr>(E) || isa<CXXOperatorCallExpr>(E)); 11953 Kind = FK_MemberFunction; 11954 CalleeType = Expr::findBoundMemberType(CalleeExpr); 11955 } else if (const PointerType *Ptr = CalleeType->getAs<PointerType>()) { 11956 CalleeType = Ptr->getPointeeType(); 11957 Kind = FK_FunctionPointer; 11958 } else { 11959 CalleeType = CalleeType->castAs<BlockPointerType>()->getPointeeType(); 11960 Kind = FK_BlockPointer; 11961 } 11962 const FunctionType *FnType = CalleeType->castAs<FunctionType>(); 11963 11964 // Verify that this is a legal result type of a function. 11965 if (DestType->isArrayType() || DestType->isFunctionType()) { 11966 unsigned diagID = diag::err_func_returning_array_function; 11967 if (Kind == FK_BlockPointer) 11968 diagID = diag::err_block_returning_array_function; 11969 11970 S.Diag(E->getExprLoc(), diagID) 11971 << DestType->isFunctionType() << DestType; 11972 return ExprError(); 11973 } 11974 11975 // Otherwise, go ahead and set DestType as the call's result. 11976 E->setType(DestType.getNonLValueExprType(S.Context)); 11977 E->setValueKind(Expr::getValueKindForType(DestType)); 11978 assert(E->getObjectKind() == OK_Ordinary); 11979 11980 // Rebuild the function type, replacing the result type with DestType. 11981 if (const FunctionProtoType *Proto = dyn_cast<FunctionProtoType>(FnType)) 11982 DestType = 11983 S.Context.getFunctionType(DestType, 11984 ArrayRef<QualType>(Proto->arg_type_begin(), 11985 Proto->getNumArgs()), 11986 Proto->getExtProtoInfo()); 11987 else 11988 DestType = S.Context.getFunctionNoProtoType(DestType, 11989 FnType->getExtInfo()); 11990 11991 // Rebuild the appropriate pointer-to-function type. 11992 switch (Kind) { 11993 case FK_MemberFunction: 11994 // Nothing to do. 11995 break; 11996 11997 case FK_FunctionPointer: 11998 DestType = S.Context.getPointerType(DestType); 11999 break; 12000 12001 case FK_BlockPointer: 12002 DestType = S.Context.getBlockPointerType(DestType); 12003 break; 12004 } 12005 12006 // Finally, we can recurse. 12007 ExprResult CalleeResult = Visit(CalleeExpr); 12008 if (!CalleeResult.isUsable()) return ExprError(); 12009 E->setCallee(CalleeResult.take()); 12010 12011 // Bind a temporary if necessary. 12012 return S.MaybeBindToTemporary(E); 12013} 12014 12015ExprResult RebuildUnknownAnyExpr::VisitObjCMessageExpr(ObjCMessageExpr *E) { 12016 // Verify that this is a legal result type of a call. 12017 if (DestType->isArrayType() || DestType->isFunctionType()) { 12018 S.Diag(E->getExprLoc(), diag::err_func_returning_array_function) 12019 << DestType->isFunctionType() << DestType; 12020 return ExprError(); 12021 } 12022 12023 // Rewrite the method result type if available. 12024 if (ObjCMethodDecl *Method = E->getMethodDecl()) { 12025 assert(Method->getResultType() == S.Context.UnknownAnyTy); 12026 Method->setResultType(DestType); 12027 } 12028 12029 // Change the type of the message. 12030 E->setType(DestType.getNonReferenceType()); 12031 E->setValueKind(Expr::getValueKindForType(DestType)); 12032 12033 return S.MaybeBindToTemporary(E); 12034} 12035 12036ExprResult RebuildUnknownAnyExpr::VisitImplicitCastExpr(ImplicitCastExpr *E) { 12037 // The only case we should ever see here is a function-to-pointer decay. 12038 if (E->getCastKind() == CK_FunctionToPointerDecay) { 12039 assert(E->getValueKind() == VK_RValue); 12040 assert(E->getObjectKind() == OK_Ordinary); 12041 12042 E->setType(DestType); 12043 12044 // Rebuild the sub-expression as the pointee (function) type. 12045 DestType = DestType->castAs<PointerType>()->getPointeeType(); 12046 12047 ExprResult Result = Visit(E->getSubExpr()); 12048 if (!Result.isUsable()) return ExprError(); 12049 12050 E->setSubExpr(Result.take()); 12051 return S.Owned(E); 12052 } else if (E->getCastKind() == CK_LValueToRValue) { 12053 assert(E->getValueKind() == VK_RValue); 12054 assert(E->getObjectKind() == OK_Ordinary); 12055 12056 assert(isa<BlockPointerType>(E->getType())); 12057 12058 E->setType(DestType); 12059 12060 // The sub-expression has to be a lvalue reference, so rebuild it as such. 12061 DestType = S.Context.getLValueReferenceType(DestType); 12062 12063 ExprResult Result = Visit(E->getSubExpr()); 12064 if (!Result.isUsable()) return ExprError(); 12065 12066 E->setSubExpr(Result.take()); 12067 return S.Owned(E); 12068 } else { 12069 llvm_unreachable("Unhandled cast type!"); 12070 } 12071} 12072 12073ExprResult RebuildUnknownAnyExpr::resolveDecl(Expr *E, ValueDecl *VD) { 12074 ExprValueKind ValueKind = VK_LValue; 12075 QualType Type = DestType; 12076 12077 // We know how to make this work for certain kinds of decls: 12078 12079 // - functions 12080 if (FunctionDecl *FD = dyn_cast<FunctionDecl>(VD)) { 12081 if (const PointerType *Ptr = Type->getAs<PointerType>()) { 12082 DestType = Ptr->getPointeeType(); 12083 ExprResult Result = resolveDecl(E, VD); 12084 if (Result.isInvalid()) return ExprError(); 12085 return S.ImpCastExprToType(Result.take(), Type, 12086 CK_FunctionToPointerDecay, VK_RValue); 12087 } 12088 12089 if (!Type->isFunctionType()) { 12090 S.Diag(E->getExprLoc(), diag::err_unknown_any_function) 12091 << VD << E->getSourceRange(); 12092 return ExprError(); 12093 } 12094 12095 if (CXXMethodDecl *MD = dyn_cast<CXXMethodDecl>(FD)) 12096 if (MD->isInstance()) { 12097 ValueKind = VK_RValue; 12098 Type = S.Context.BoundMemberTy; 12099 } 12100 12101 // Function references aren't l-values in C. 12102 if (!S.getLangOpts().CPlusPlus) 12103 ValueKind = VK_RValue; 12104 12105 // - variables 12106 } else if (isa<VarDecl>(VD)) { 12107 if (const ReferenceType *RefTy = Type->getAs<ReferenceType>()) { 12108 Type = RefTy->getPointeeType(); 12109 } else if (Type->isFunctionType()) { 12110 S.Diag(E->getExprLoc(), diag::err_unknown_any_var_function_type) 12111 << VD << E->getSourceRange(); 12112 return ExprError(); 12113 } 12114 12115 // - nothing else 12116 } else { 12117 S.Diag(E->getExprLoc(), diag::err_unsupported_unknown_any_decl) 12118 << VD << E->getSourceRange(); 12119 return ExprError(); 12120 } 12121 12122 VD->setType(DestType); 12123 E->setType(Type); 12124 E->setValueKind(ValueKind); 12125 return S.Owned(E); 12126} 12127 12128/// Check a cast of an unknown-any type. We intentionally only 12129/// trigger this for C-style casts. 12130ExprResult Sema::checkUnknownAnyCast(SourceRange TypeRange, QualType CastType, 12131 Expr *CastExpr, CastKind &CastKind, 12132 ExprValueKind &VK, CXXCastPath &Path) { 12133 // Rewrite the casted expression from scratch. 12134 ExprResult result = RebuildUnknownAnyExpr(*this, CastType).Visit(CastExpr); 12135 if (!result.isUsable()) return ExprError(); 12136 12137 CastExpr = result.take(); 12138 VK = CastExpr->getValueKind(); 12139 CastKind = CK_NoOp; 12140 12141 return CastExpr; 12142} 12143 12144ExprResult Sema::forceUnknownAnyToType(Expr *E, QualType ToType) { 12145 return RebuildUnknownAnyExpr(*this, ToType).Visit(E); 12146} 12147 12148ExprResult Sema::checkUnknownAnyArg(SourceLocation callLoc, 12149 Expr *arg, QualType ¶mType) { 12150 // If the syntactic form of the argument is not an explicit cast of 12151 // any sort, just do default argument promotion. 12152 ExplicitCastExpr *castArg = dyn_cast<ExplicitCastExpr>(arg->IgnoreParens()); 12153 if (!castArg) { 12154 ExprResult result = DefaultArgumentPromotion(arg); 12155 if (result.isInvalid()) return ExprError(); 12156 paramType = result.get()->getType(); 12157 return result; 12158 } 12159 12160 // Otherwise, use the type that was written in the explicit cast. 12161 assert(!arg->hasPlaceholderType()); 12162 paramType = castArg->getTypeAsWritten(); 12163 12164 // Copy-initialize a parameter of that type. 12165 InitializedEntity entity = 12166 InitializedEntity::InitializeParameter(Context, paramType, 12167 /*consumed*/ false); 12168 return PerformCopyInitialization(entity, callLoc, Owned(arg)); 12169} 12170 12171static ExprResult diagnoseUnknownAnyExpr(Sema &S, Expr *E) { 12172 Expr *orig = E; 12173 unsigned diagID = diag::err_uncasted_use_of_unknown_any; 12174 while (true) { 12175 E = E->IgnoreParenImpCasts(); 12176 if (CallExpr *call = dyn_cast<CallExpr>(E)) { 12177 E = call->getCallee(); 12178 diagID = diag::err_uncasted_call_of_unknown_any; 12179 } else { 12180 break; 12181 } 12182 } 12183 12184 SourceLocation loc; 12185 NamedDecl *d; 12186 if (DeclRefExpr *ref = dyn_cast<DeclRefExpr>(E)) { 12187 loc = ref->getLocation(); 12188 d = ref->getDecl(); 12189 } else if (MemberExpr *mem = dyn_cast<MemberExpr>(E)) { 12190 loc = mem->getMemberLoc(); 12191 d = mem->getMemberDecl(); 12192 } else if (ObjCMessageExpr *msg = dyn_cast<ObjCMessageExpr>(E)) { 12193 diagID = diag::err_uncasted_call_of_unknown_any; 12194 loc = msg->getSelectorStartLoc(); 12195 d = msg->getMethodDecl(); 12196 if (!d) { 12197 S.Diag(loc, diag::err_uncasted_send_to_unknown_any_method) 12198 << static_cast<unsigned>(msg->isClassMessage()) << msg->getSelector() 12199 << orig->getSourceRange(); 12200 return ExprError(); 12201 } 12202 } else { 12203 S.Diag(E->getExprLoc(), diag::err_unsupported_unknown_any_expr) 12204 << E->getSourceRange(); 12205 return ExprError(); 12206 } 12207 12208 S.Diag(loc, diagID) << d << orig->getSourceRange(); 12209 12210 // Never recoverable. 12211 return ExprError(); 12212} 12213 12214/// Check for operands with placeholder types and complain if found. 12215/// Returns true if there was an error and no recovery was possible. 12216ExprResult Sema::CheckPlaceholderExpr(Expr *E) { 12217 const BuiltinType *placeholderType = E->getType()->getAsPlaceholderType(); 12218 if (!placeholderType) return Owned(E); 12219 12220 switch (placeholderType->getKind()) { 12221 12222 // Overloaded expressions. 12223 case BuiltinType::Overload: { 12224 // Try to resolve a single function template specialization. 12225 // This is obligatory. 12226 ExprResult result = Owned(E); 12227 if (ResolveAndFixSingleFunctionTemplateSpecialization(result, false)) { 12228 return result; 12229 12230 // If that failed, try to recover with a call. 12231 } else { 12232 tryToRecoverWithCall(result, PDiag(diag::err_ovl_unresolvable), 12233 /*complain*/ true); 12234 return result; 12235 } 12236 } 12237 12238 // Bound member functions. 12239 case BuiltinType::BoundMember: { 12240 ExprResult result = Owned(E); 12241 tryToRecoverWithCall(result, PDiag(diag::err_bound_member_function), 12242 /*complain*/ true); 12243 return result; 12244 } 12245 12246 // ARC unbridged casts. 12247 case BuiltinType::ARCUnbridgedCast: { 12248 Expr *realCast = stripARCUnbridgedCast(E); 12249 diagnoseARCUnbridgedCast(realCast); 12250 return Owned(realCast); 12251 } 12252 12253 // Expressions of unknown type. 12254 case BuiltinType::UnknownAny: 12255 return diagnoseUnknownAnyExpr(*this, E); 12256 12257 // Pseudo-objects. 12258 case BuiltinType::PseudoObject: 12259 return checkPseudoObjectRValue(E); 12260 12261 case BuiltinType::BuiltinFn: 12262 Diag(E->getLocStart(), diag::err_builtin_fn_use); 12263 return ExprError(); 12264 12265 // Everything else should be impossible. 12266#define BUILTIN_TYPE(Id, SingletonId) \ 12267 case BuiltinType::Id: 12268#define PLACEHOLDER_TYPE(Id, SingletonId) 12269#include "clang/AST/BuiltinTypes.def" 12270 break; 12271 } 12272 12273 llvm_unreachable("invalid placeholder type!"); 12274} 12275 12276bool Sema::CheckCaseExpression(Expr *E) { 12277 if (E->isTypeDependent()) 12278 return true; 12279 if (E->isValueDependent() || E->isIntegerConstantExpr(Context)) 12280 return E->getType()->isIntegralOrEnumerationType(); 12281 return false; 12282} 12283 12284/// ActOnObjCBoolLiteral - Parse {__objc_yes,__objc_no} literals. 12285ExprResult 12286Sema::ActOnObjCBoolLiteral(SourceLocation OpLoc, tok::TokenKind Kind) { 12287 assert((Kind == tok::kw___objc_yes || Kind == tok::kw___objc_no) && 12288 "Unknown Objective-C Boolean value!"); 12289 QualType BoolT = Context.ObjCBuiltinBoolTy; 12290 if (!Context.getBOOLDecl()) { 12291 LookupResult Result(*this, &Context.Idents.get("BOOL"), OpLoc, 12292 Sema::LookupOrdinaryName); 12293 if (LookupName(Result, getCurScope()) && Result.isSingleResult()) { 12294 NamedDecl *ND = Result.getFoundDecl(); 12295 if (TypedefDecl *TD = dyn_cast<TypedefDecl>(ND)) 12296 Context.setBOOLDecl(TD); 12297 } 12298 } 12299 if (Context.getBOOLDecl()) 12300 BoolT = Context.getBOOLType(); 12301 return Owned(new (Context) ObjCBoolLiteralExpr(Kind == tok::kw___objc_yes, 12302 BoolT, OpLoc)); 12303} 12304