SemaExpr.cpp revision b49da815d5fc3299dc8e8bbf1886f0a193ad8894
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 "Sema.h" 15#include "Lookup.h" 16#include "clang/AST/ASTContext.h" 17#include "clang/AST/DeclObjC.h" 18#include "clang/AST/DeclTemplate.h" 19#include "clang/AST/ExprCXX.h" 20#include "clang/AST/ExprObjC.h" 21#include "clang/Basic/PartialDiagnostic.h" 22#include "clang/Basic/SourceManager.h" 23#include "clang/Basic/TargetInfo.h" 24#include "clang/Lex/LiteralSupport.h" 25#include "clang/Lex/Preprocessor.h" 26#include "clang/Parse/DeclSpec.h" 27#include "clang/Parse/Designator.h" 28#include "clang/Parse/Scope.h" 29#include "clang/Parse/Template.h" 30using namespace clang; 31 32 33/// \brief Determine whether the use of this declaration is valid, and 34/// emit any corresponding diagnostics. 35/// 36/// This routine diagnoses various problems with referencing 37/// declarations that can occur when using a declaration. For example, 38/// it might warn if a deprecated or unavailable declaration is being 39/// used, or produce an error (and return true) if a C++0x deleted 40/// function is being used. 41/// 42/// If IgnoreDeprecated is set to true, this should not want about deprecated 43/// decls. 44/// 45/// \returns true if there was an error (this declaration cannot be 46/// referenced), false otherwise. 47/// 48bool Sema::DiagnoseUseOfDecl(NamedDecl *D, SourceLocation Loc) { 49 // See if the decl is deprecated. 50 if (D->getAttr<DeprecatedAttr>()) { 51 EmitDeprecationWarning(D, Loc); 52 } 53 54 // See if the decl is unavailable 55 if (D->getAttr<UnavailableAttr>()) { 56 Diag(Loc, diag::warn_unavailable) << D->getDeclName(); 57 Diag(D->getLocation(), diag::note_unavailable_here) << 0; 58 } 59 60 // See if this is a deleted function. 61 if (FunctionDecl *FD = dyn_cast<FunctionDecl>(D)) { 62 if (FD->isDeleted()) { 63 Diag(Loc, diag::err_deleted_function_use); 64 Diag(D->getLocation(), diag::note_unavailable_here) << true; 65 return true; 66 } 67 } 68 69 return false; 70} 71 72/// DiagnoseSentinelCalls - This routine checks on method dispatch calls 73/// (and other functions in future), which have been declared with sentinel 74/// attribute. It warns if call does not have the sentinel argument. 75/// 76void Sema::DiagnoseSentinelCalls(NamedDecl *D, SourceLocation Loc, 77 Expr **Args, unsigned NumArgs) { 78 const SentinelAttr *attr = D->getAttr<SentinelAttr>(); 79 if (!attr) 80 return; 81 int sentinelPos = attr->getSentinel(); 82 int nullPos = attr->getNullPos(); 83 84 // FIXME. ObjCMethodDecl and FunctionDecl need be derived from the same common 85 // base class. Then we won't be needing two versions of the same code. 86 unsigned int i = 0; 87 bool warnNotEnoughArgs = false; 88 int isMethod = 0; 89 if (ObjCMethodDecl *MD = dyn_cast<ObjCMethodDecl>(D)) { 90 // skip over named parameters. 91 ObjCMethodDecl::param_iterator P, E = MD->param_end(); 92 for (P = MD->param_begin(); (P != E && i < NumArgs); ++P) { 93 if (nullPos) 94 --nullPos; 95 else 96 ++i; 97 } 98 warnNotEnoughArgs = (P != E || i >= NumArgs); 99 isMethod = 1; 100 } else if (FunctionDecl *FD = dyn_cast<FunctionDecl>(D)) { 101 // skip over named parameters. 102 ObjCMethodDecl::param_iterator P, E = FD->param_end(); 103 for (P = FD->param_begin(); (P != E && i < NumArgs); ++P) { 104 if (nullPos) 105 --nullPos; 106 else 107 ++i; 108 } 109 warnNotEnoughArgs = (P != E || i >= NumArgs); 110 } else if (VarDecl *V = dyn_cast<VarDecl>(D)) { 111 // block or function pointer call. 112 QualType Ty = V->getType(); 113 if (Ty->isBlockPointerType() || Ty->isFunctionPointerType()) { 114 const FunctionType *FT = Ty->isFunctionPointerType() 115 ? Ty->getAs<PointerType>()->getPointeeType()->getAs<FunctionType>() 116 : Ty->getAs<BlockPointerType>()->getPointeeType()->getAs<FunctionType>(); 117 if (const FunctionProtoType *Proto = dyn_cast<FunctionProtoType>(FT)) { 118 unsigned NumArgsInProto = Proto->getNumArgs(); 119 unsigned k; 120 for (k = 0; (k != NumArgsInProto && i < NumArgs); k++) { 121 if (nullPos) 122 --nullPos; 123 else 124 ++i; 125 } 126 warnNotEnoughArgs = (k != NumArgsInProto || i >= NumArgs); 127 } 128 if (Ty->isBlockPointerType()) 129 isMethod = 2; 130 } else 131 return; 132 } else 133 return; 134 135 if (warnNotEnoughArgs) { 136 Diag(Loc, diag::warn_not_enough_argument) << D->getDeclName(); 137 Diag(D->getLocation(), diag::note_sentinel_here) << isMethod; 138 return; 139 } 140 int sentinel = i; 141 while (sentinelPos > 0 && i < NumArgs-1) { 142 --sentinelPos; 143 ++i; 144 } 145 if (sentinelPos > 0) { 146 Diag(Loc, diag::warn_not_enough_argument) << D->getDeclName(); 147 Diag(D->getLocation(), diag::note_sentinel_here) << isMethod; 148 return; 149 } 150 while (i < NumArgs-1) { 151 ++i; 152 ++sentinel; 153 } 154 Expr *sentinelExpr = Args[sentinel]; 155 if (sentinelExpr && (!isa<GNUNullExpr>(sentinelExpr) && 156 (!sentinelExpr->getType()->isPointerType() || 157 !sentinelExpr->isNullPointerConstant(Context, 158 Expr::NPC_ValueDependentIsNull)))) { 159 Diag(Loc, diag::warn_missing_sentinel) << isMethod; 160 Diag(D->getLocation(), diag::note_sentinel_here) << isMethod; 161 } 162 return; 163} 164 165SourceRange Sema::getExprRange(ExprTy *E) const { 166 Expr *Ex = (Expr *)E; 167 return Ex? Ex->getSourceRange() : SourceRange(); 168} 169 170//===----------------------------------------------------------------------===// 171// Standard Promotions and Conversions 172//===----------------------------------------------------------------------===// 173 174/// DefaultFunctionArrayConversion (C99 6.3.2.1p3, C99 6.3.2.1p4). 175void Sema::DefaultFunctionArrayConversion(Expr *&E) { 176 QualType Ty = E->getType(); 177 assert(!Ty.isNull() && "DefaultFunctionArrayConversion - missing type"); 178 179 if (Ty->isFunctionType()) 180 ImpCastExprToType(E, Context.getPointerType(Ty), 181 CastExpr::CK_FunctionToPointerDecay); 182 else if (Ty->isArrayType()) { 183 // In C90 mode, arrays only promote to pointers if the array expression is 184 // an lvalue. The relevant legalese is C90 6.2.2.1p3: "an lvalue that has 185 // type 'array of type' is converted to an expression that has type 'pointer 186 // to type'...". In C99 this was changed to: C99 6.3.2.1p3: "an expression 187 // that has type 'array of type' ...". The relevant change is "an lvalue" 188 // (C90) to "an expression" (C99). 189 // 190 // C++ 4.2p1: 191 // An lvalue or rvalue of type "array of N T" or "array of unknown bound of 192 // T" can be converted to an rvalue of type "pointer to T". 193 // 194 if (getLangOptions().C99 || getLangOptions().CPlusPlus || 195 E->isLvalue(Context) == Expr::LV_Valid) 196 ImpCastExprToType(E, Context.getArrayDecayedType(Ty), 197 CastExpr::CK_ArrayToPointerDecay); 198 } 199} 200 201/// UsualUnaryConversions - Performs various conversions that are common to most 202/// operators (C99 6.3). The conversions of array and function types are 203/// sometimes surpressed. For example, the array->pointer conversion doesn't 204/// apply if the array is an argument to the sizeof or address (&) operators. 205/// In these instances, this routine should *not* be called. 206Expr *Sema::UsualUnaryConversions(Expr *&Expr) { 207 QualType Ty = Expr->getType(); 208 assert(!Ty.isNull() && "UsualUnaryConversions - missing type"); 209 210 // C99 6.3.1.1p2: 211 // 212 // The following may be used in an expression wherever an int or 213 // unsigned int may be used: 214 // - an object or expression with an integer type whose integer 215 // conversion rank is less than or equal to the rank of int 216 // and unsigned int. 217 // - A bit-field of type _Bool, int, signed int, or unsigned int. 218 // 219 // If an int can represent all values of the original type, the 220 // value is converted to an int; otherwise, it is converted to an 221 // unsigned int. These are called the integer promotions. All 222 // other types are unchanged by the integer promotions. 223 QualType PTy = Context.isPromotableBitField(Expr); 224 if (!PTy.isNull()) { 225 ImpCastExprToType(Expr, PTy, CastExpr::CK_IntegralCast); 226 return Expr; 227 } 228 if (Ty->isPromotableIntegerType()) { 229 QualType PT = Context.getPromotedIntegerType(Ty); 230 ImpCastExprToType(Expr, PT, CastExpr::CK_IntegralCast); 231 return Expr; 232 } 233 234 DefaultFunctionArrayConversion(Expr); 235 return Expr; 236} 237 238/// DefaultArgumentPromotion (C99 6.5.2.2p6). Used for function calls that 239/// do not have a prototype. Arguments that have type float are promoted to 240/// double. All other argument types are converted by UsualUnaryConversions(). 241void Sema::DefaultArgumentPromotion(Expr *&Expr) { 242 QualType Ty = Expr->getType(); 243 assert(!Ty.isNull() && "DefaultArgumentPromotion - missing type"); 244 245 // If this is a 'float' (CVR qualified or typedef) promote to double. 246 if (const BuiltinType *BT = Ty->getAs<BuiltinType>()) 247 if (BT->getKind() == BuiltinType::Float) 248 return ImpCastExprToType(Expr, Context.DoubleTy, 249 CastExpr::CK_FloatingCast); 250 251 UsualUnaryConversions(Expr); 252} 253 254/// DefaultVariadicArgumentPromotion - Like DefaultArgumentPromotion, but 255/// will warn if the resulting type is not a POD type, and rejects ObjC 256/// interfaces passed by value. This returns true if the argument type is 257/// completely illegal. 258bool Sema::DefaultVariadicArgumentPromotion(Expr *&Expr, VariadicCallType CT) { 259 DefaultArgumentPromotion(Expr); 260 261 if (Expr->getType()->isObjCInterfaceType()) { 262 switch (ExprEvalContexts.back().Context ) { 263 case Unevaluated: 264 // The argument will never be evaluated, so don't complain. 265 break; 266 267 case PotentiallyEvaluated: 268 Diag(Expr->getLocStart(), 269 diag::err_cannot_pass_objc_interface_to_vararg) 270 << Expr->getType() << CT; 271 return true; 272 273 case PotentiallyPotentiallyEvaluated: 274 ExprEvalContexts.back().addDiagnostic(Expr->getLocStart(), 275 PDiag(diag::err_cannot_pass_objc_interface_to_vararg) 276 << Expr->getType() << CT); 277 break; 278 } 279 } 280 281 if (!Expr->getType()->isPODType()) { 282 switch (ExprEvalContexts.back().Context ) { 283 case Unevaluated: 284 // The argument will never be evaluated, so don't complain. 285 break; 286 287 case PotentiallyEvaluated: 288 Diag(Expr->getLocStart(), diag::warn_cannot_pass_non_pod_arg_to_vararg) 289 << Expr->getType() << CT; 290 break; 291 292 case PotentiallyPotentiallyEvaluated: 293 ExprEvalContexts.back().addDiagnostic(Expr->getLocStart(), 294 PDiag(diag::warn_cannot_pass_non_pod_arg_to_vararg) 295 << Expr->getType() << CT); 296 break; 297 } 298 } 299 300 return false; 301} 302 303 304/// UsualArithmeticConversions - Performs various conversions that are common to 305/// binary operators (C99 6.3.1.8). If both operands aren't arithmetic, this 306/// routine returns the first non-arithmetic type found. The client is 307/// responsible for emitting appropriate error diagnostics. 308/// FIXME: verify the conversion rules for "complex int" are consistent with 309/// GCC. 310QualType Sema::UsualArithmeticConversions(Expr *&lhsExpr, Expr *&rhsExpr, 311 bool isCompAssign) { 312 if (!isCompAssign) 313 UsualUnaryConversions(lhsExpr); 314 315 UsualUnaryConversions(rhsExpr); 316 317 // For conversion purposes, we ignore any qualifiers. 318 // For example, "const float" and "float" are equivalent. 319 QualType lhs = 320 Context.getCanonicalType(lhsExpr->getType()).getUnqualifiedType(); 321 QualType rhs = 322 Context.getCanonicalType(rhsExpr->getType()).getUnqualifiedType(); 323 324 // If both types are identical, no conversion is needed. 325 if (lhs == rhs) 326 return lhs; 327 328 // If either side is a non-arithmetic type (e.g. a pointer), we are done. 329 // The caller can deal with this (e.g. pointer + int). 330 if (!lhs->isArithmeticType() || !rhs->isArithmeticType()) 331 return lhs; 332 333 // Perform bitfield promotions. 334 QualType LHSBitfieldPromoteTy = Context.isPromotableBitField(lhsExpr); 335 if (!LHSBitfieldPromoteTy.isNull()) 336 lhs = LHSBitfieldPromoteTy; 337 QualType RHSBitfieldPromoteTy = Context.isPromotableBitField(rhsExpr); 338 if (!RHSBitfieldPromoteTy.isNull()) 339 rhs = RHSBitfieldPromoteTy; 340 341 QualType destType = Context.UsualArithmeticConversionsType(lhs, rhs); 342 if (!isCompAssign) 343 ImpCastExprToType(lhsExpr, destType, CastExpr::CK_Unknown); 344 ImpCastExprToType(rhsExpr, destType, CastExpr::CK_Unknown); 345 return destType; 346} 347 348//===----------------------------------------------------------------------===// 349// Semantic Analysis for various Expression Types 350//===----------------------------------------------------------------------===// 351 352 353/// ActOnStringLiteral - The specified tokens were lexed as pasted string 354/// fragments (e.g. "foo" "bar" L"baz"). The result string has to handle string 355/// concatenation ([C99 5.1.1.2, translation phase #6]), so it may come from 356/// multiple tokens. However, the common case is that StringToks points to one 357/// string. 358/// 359Action::OwningExprResult 360Sema::ActOnStringLiteral(const Token *StringToks, unsigned NumStringToks) { 361 assert(NumStringToks && "Must have at least one string!"); 362 363 StringLiteralParser Literal(StringToks, NumStringToks, PP); 364 if (Literal.hadError) 365 return ExprError(); 366 367 llvm::SmallVector<SourceLocation, 4> StringTokLocs; 368 for (unsigned i = 0; i != NumStringToks; ++i) 369 StringTokLocs.push_back(StringToks[i].getLocation()); 370 371 QualType StrTy = Context.CharTy; 372 if (Literal.AnyWide) StrTy = Context.getWCharType(); 373 if (Literal.Pascal) StrTy = Context.UnsignedCharTy; 374 375 // A C++ string literal has a const-qualified element type (C++ 2.13.4p1). 376 if (getLangOptions().CPlusPlus) 377 StrTy.addConst(); 378 379 // Get an array type for the string, according to C99 6.4.5. This includes 380 // the nul terminator character as well as the string length for pascal 381 // strings. 382 StrTy = Context.getConstantArrayType(StrTy, 383 llvm::APInt(32, Literal.GetNumStringChars()+1), 384 ArrayType::Normal, 0); 385 386 // Pass &StringTokLocs[0], StringTokLocs.size() to factory! 387 return Owned(StringLiteral::Create(Context, Literal.GetString(), 388 Literal.GetStringLength(), 389 Literal.AnyWide, StrTy, 390 &StringTokLocs[0], 391 StringTokLocs.size())); 392} 393 394/// ShouldSnapshotBlockValueReference - Return true if a reference inside of 395/// CurBlock to VD should cause it to be snapshotted (as we do for auto 396/// variables defined outside the block) or false if this is not needed (e.g. 397/// for values inside the block or for globals). 398/// 399/// This also keeps the 'hasBlockDeclRefExprs' in the BlockSemaInfo records 400/// up-to-date. 401/// 402static bool ShouldSnapshotBlockValueReference(BlockSemaInfo *CurBlock, 403 ValueDecl *VD) { 404 // If the value is defined inside the block, we couldn't snapshot it even if 405 // we wanted to. 406 if (CurBlock->TheDecl == VD->getDeclContext()) 407 return false; 408 409 // If this is an enum constant or function, it is constant, don't snapshot. 410 if (isa<EnumConstantDecl>(VD) || isa<FunctionDecl>(VD)) 411 return false; 412 413 // If this is a reference to an extern, static, or global variable, no need to 414 // snapshot it. 415 // FIXME: What about 'const' variables in C++? 416 if (const VarDecl *Var = dyn_cast<VarDecl>(VD)) 417 if (!Var->hasLocalStorage()) 418 return false; 419 420 // Blocks that have these can't be constant. 421 CurBlock->hasBlockDeclRefExprs = true; 422 423 // If we have nested blocks, the decl may be declared in an outer block (in 424 // which case that outer block doesn't get "hasBlockDeclRefExprs") or it may 425 // be defined outside all of the current blocks (in which case the blocks do 426 // all get the bit). Walk the nesting chain. 427 for (BlockSemaInfo *NextBlock = CurBlock->PrevBlockInfo; NextBlock; 428 NextBlock = NextBlock->PrevBlockInfo) { 429 // If we found the defining block for the variable, don't mark the block as 430 // having a reference outside it. 431 if (NextBlock->TheDecl == VD->getDeclContext()) 432 break; 433 434 // Otherwise, the DeclRef from the inner block causes the outer one to need 435 // a snapshot as well. 436 NextBlock->hasBlockDeclRefExprs = true; 437 } 438 439 return true; 440} 441 442 443 444/// BuildDeclRefExpr - Build a DeclRefExpr. 445Sema::OwningExprResult 446Sema::BuildDeclRefExpr(ValueDecl *D, QualType Ty, SourceLocation Loc, 447 const CXXScopeSpec *SS) { 448 if (Context.getCanonicalType(Ty) == Context.UndeducedAutoTy) { 449 Diag(Loc, 450 diag::err_auto_variable_cannot_appear_in_own_initializer) 451 << D->getDeclName(); 452 return ExprError(); 453 } 454 455 if (const VarDecl *VD = dyn_cast<VarDecl>(D)) { 456 if (const CXXMethodDecl *MD = dyn_cast<CXXMethodDecl>(CurContext)) { 457 if (const FunctionDecl *FD = MD->getParent()->isLocalClass()) { 458 if (VD->hasLocalStorage() && VD->getDeclContext() != CurContext) { 459 Diag(Loc, diag::err_reference_to_local_var_in_enclosing_function) 460 << D->getIdentifier() << FD->getDeclName(); 461 Diag(D->getLocation(), diag::note_local_variable_declared_here) 462 << D->getIdentifier(); 463 return ExprError(); 464 } 465 } 466 } 467 } 468 469 MarkDeclarationReferenced(Loc, D); 470 471 return Owned(DeclRefExpr::Create(Context, 472 SS? (NestedNameSpecifier *)SS->getScopeRep() : 0, 473 SS? SS->getRange() : SourceRange(), 474 D, Loc, Ty)); 475} 476 477/// getObjectForAnonymousRecordDecl - Retrieve the (unnamed) field or 478/// variable corresponding to the anonymous union or struct whose type 479/// is Record. 480static Decl *getObjectForAnonymousRecordDecl(ASTContext &Context, 481 RecordDecl *Record) { 482 assert(Record->isAnonymousStructOrUnion() && 483 "Record must be an anonymous struct or union!"); 484 485 // FIXME: Once Decls are directly linked together, this will be an O(1) 486 // operation rather than a slow walk through DeclContext's vector (which 487 // itself will be eliminated). DeclGroups might make this even better. 488 DeclContext *Ctx = Record->getDeclContext(); 489 for (DeclContext::decl_iterator D = Ctx->decls_begin(), 490 DEnd = Ctx->decls_end(); 491 D != DEnd; ++D) { 492 if (*D == Record) { 493 // The object for the anonymous struct/union directly 494 // follows its type in the list of declarations. 495 ++D; 496 assert(D != DEnd && "Missing object for anonymous record"); 497 assert(!cast<NamedDecl>(*D)->getDeclName() && "Decl should be unnamed"); 498 return *D; 499 } 500 } 501 502 assert(false && "Missing object for anonymous record"); 503 return 0; 504} 505 506/// \brief Given a field that represents a member of an anonymous 507/// struct/union, build the path from that field's context to the 508/// actual member. 509/// 510/// Construct the sequence of field member references we'll have to 511/// perform to get to the field in the anonymous union/struct. The 512/// list of members is built from the field outward, so traverse it 513/// backwards to go from an object in the current context to the field 514/// we found. 515/// 516/// \returns The variable from which the field access should begin, 517/// for an anonymous struct/union that is not a member of another 518/// class. Otherwise, returns NULL. 519VarDecl *Sema::BuildAnonymousStructUnionMemberPath(FieldDecl *Field, 520 llvm::SmallVectorImpl<FieldDecl *> &Path) { 521 assert(Field->getDeclContext()->isRecord() && 522 cast<RecordDecl>(Field->getDeclContext())->isAnonymousStructOrUnion() 523 && "Field must be stored inside an anonymous struct or union"); 524 525 Path.push_back(Field); 526 VarDecl *BaseObject = 0; 527 DeclContext *Ctx = Field->getDeclContext(); 528 do { 529 RecordDecl *Record = cast<RecordDecl>(Ctx); 530 Decl *AnonObject = getObjectForAnonymousRecordDecl(Context, Record); 531 if (FieldDecl *AnonField = dyn_cast<FieldDecl>(AnonObject)) 532 Path.push_back(AnonField); 533 else { 534 BaseObject = cast<VarDecl>(AnonObject); 535 break; 536 } 537 Ctx = Ctx->getParent(); 538 } while (Ctx->isRecord() && 539 cast<RecordDecl>(Ctx)->isAnonymousStructOrUnion()); 540 541 return BaseObject; 542} 543 544Sema::OwningExprResult 545Sema::BuildAnonymousStructUnionMemberReference(SourceLocation Loc, 546 FieldDecl *Field, 547 Expr *BaseObjectExpr, 548 SourceLocation OpLoc) { 549 llvm::SmallVector<FieldDecl *, 4> AnonFields; 550 VarDecl *BaseObject = BuildAnonymousStructUnionMemberPath(Field, 551 AnonFields); 552 553 // Build the expression that refers to the base object, from 554 // which we will build a sequence of member references to each 555 // of the anonymous union objects and, eventually, the field we 556 // found via name lookup. 557 bool BaseObjectIsPointer = false; 558 Qualifiers BaseQuals; 559 if (BaseObject) { 560 // BaseObject is an anonymous struct/union variable (and is, 561 // therefore, not part of another non-anonymous record). 562 if (BaseObjectExpr) BaseObjectExpr->Destroy(Context); 563 MarkDeclarationReferenced(Loc, BaseObject); 564 BaseObjectExpr = new (Context) DeclRefExpr(BaseObject,BaseObject->getType(), 565 SourceLocation()); 566 BaseQuals 567 = Context.getCanonicalType(BaseObject->getType()).getQualifiers(); 568 } else if (BaseObjectExpr) { 569 // The caller provided the base object expression. Determine 570 // whether its a pointer and whether it adds any qualifiers to the 571 // anonymous struct/union fields we're looking into. 572 QualType ObjectType = BaseObjectExpr->getType(); 573 if (const PointerType *ObjectPtr = ObjectType->getAs<PointerType>()) { 574 BaseObjectIsPointer = true; 575 ObjectType = ObjectPtr->getPointeeType(); 576 } 577 BaseQuals 578 = Context.getCanonicalType(ObjectType).getQualifiers(); 579 } else { 580 // We've found a member of an anonymous struct/union that is 581 // inside a non-anonymous struct/union, so in a well-formed 582 // program our base object expression is "this". 583 if (CXXMethodDecl *MD = dyn_cast<CXXMethodDecl>(CurContext)) { 584 if (!MD->isStatic()) { 585 QualType AnonFieldType 586 = Context.getTagDeclType( 587 cast<RecordDecl>(AnonFields.back()->getDeclContext())); 588 QualType ThisType = Context.getTagDeclType(MD->getParent()); 589 if ((Context.getCanonicalType(AnonFieldType) 590 == Context.getCanonicalType(ThisType)) || 591 IsDerivedFrom(ThisType, AnonFieldType)) { 592 // Our base object expression is "this". 593 BaseObjectExpr = new (Context) CXXThisExpr(SourceLocation(), 594 MD->getThisType(Context)); 595 BaseObjectIsPointer = true; 596 } 597 } else { 598 return ExprError(Diag(Loc,diag::err_invalid_member_use_in_static_method) 599 << Field->getDeclName()); 600 } 601 BaseQuals = Qualifiers::fromCVRMask(MD->getTypeQualifiers()); 602 } 603 604 if (!BaseObjectExpr) 605 return ExprError(Diag(Loc, diag::err_invalid_non_static_member_use) 606 << Field->getDeclName()); 607 } 608 609 // Build the implicit member references to the field of the 610 // anonymous struct/union. 611 Expr *Result = BaseObjectExpr; 612 Qualifiers ResultQuals = BaseQuals; 613 for (llvm::SmallVector<FieldDecl *, 4>::reverse_iterator 614 FI = AnonFields.rbegin(), FIEnd = AnonFields.rend(); 615 FI != FIEnd; ++FI) { 616 QualType MemberType = (*FI)->getType(); 617 Qualifiers MemberTypeQuals = 618 Context.getCanonicalType(MemberType).getQualifiers(); 619 620 // CVR attributes from the base are picked up by members, 621 // except that 'mutable' members don't pick up 'const'. 622 if ((*FI)->isMutable()) 623 ResultQuals.removeConst(); 624 625 // GC attributes are never picked up by members. 626 ResultQuals.removeObjCGCAttr(); 627 628 // TR 18037 does not allow fields to be declared with address spaces. 629 assert(!MemberTypeQuals.hasAddressSpace()); 630 631 Qualifiers NewQuals = ResultQuals + MemberTypeQuals; 632 if (NewQuals != MemberTypeQuals) 633 MemberType = Context.getQualifiedType(MemberType, NewQuals); 634 635 MarkDeclarationReferenced(Loc, *FI); 636 PerformObjectMemberConversion(Result, *FI); 637 // FIXME: Might this end up being a qualified name? 638 Result = new (Context) MemberExpr(Result, BaseObjectIsPointer, *FI, 639 OpLoc, MemberType); 640 BaseObjectIsPointer = false; 641 ResultQuals = NewQuals; 642 } 643 644 return Owned(Result); 645} 646 647/// Decomposes the given name into a DeclarationName, its location, and 648/// possibly a list of template arguments. 649/// 650/// If this produces template arguments, it is permitted to call 651/// DecomposeTemplateName. 652/// 653/// This actually loses a lot of source location information for 654/// non-standard name kinds; we should consider preserving that in 655/// some way. 656static void DecomposeUnqualifiedId(Sema &SemaRef, 657 const UnqualifiedId &Id, 658 TemplateArgumentListInfo &Buffer, 659 DeclarationName &Name, 660 SourceLocation &NameLoc, 661 const TemplateArgumentListInfo *&TemplateArgs) { 662 if (Id.getKind() == UnqualifiedId::IK_TemplateId) { 663 Buffer.setLAngleLoc(Id.TemplateId->LAngleLoc); 664 Buffer.setRAngleLoc(Id.TemplateId->RAngleLoc); 665 666 ASTTemplateArgsPtr TemplateArgsPtr(SemaRef, 667 Id.TemplateId->getTemplateArgs(), 668 Id.TemplateId->NumArgs); 669 SemaRef.translateTemplateArguments(TemplateArgsPtr, Buffer); 670 TemplateArgsPtr.release(); 671 672 TemplateName TName = 673 Sema::TemplateTy::make(Id.TemplateId->Template).getAsVal<TemplateName>(); 674 675 Name = SemaRef.Context.getNameForTemplate(TName); 676 NameLoc = Id.TemplateId->TemplateNameLoc; 677 TemplateArgs = &Buffer; 678 } else { 679 Name = SemaRef.GetNameFromUnqualifiedId(Id); 680 NameLoc = Id.StartLocation; 681 TemplateArgs = 0; 682 } 683} 684 685/// Decompose the given template name into a list of lookup results. 686/// 687/// The unqualified ID must name a non-dependent template, which can 688/// be more easily tested by checking whether DecomposeUnqualifiedId 689/// found template arguments. 690static void DecomposeTemplateName(LookupResult &R, const UnqualifiedId &Id) { 691 assert(Id.getKind() == UnqualifiedId::IK_TemplateId); 692 TemplateName TName = 693 Sema::TemplateTy::make(Id.TemplateId->Template).getAsVal<TemplateName>(); 694 695 if (TemplateDecl *TD = TName.getAsTemplateDecl()) 696 R.addDecl(TD); 697 else if (OverloadedTemplateStorage *OT = TName.getAsOverloadedTemplate()) 698 for (OverloadedTemplateStorage::iterator I = OT->begin(), E = OT->end(); 699 I != E; ++I) 700 R.addDecl(*I); 701 702 R.resolveKind(); 703} 704 705static bool IsFullyFormedScope(Sema &SemaRef, CXXRecordDecl *Record) { 706 for (CXXRecordDecl::base_class_iterator I = Record->bases_begin(), 707 E = Record->bases_end(); I != E; ++I) { 708 CanQualType BaseT = SemaRef.Context.getCanonicalType((*I).getType()); 709 CanQual<RecordType> BaseRT = BaseT->getAs<RecordType>(); 710 if (!BaseRT) return false; 711 712 CXXRecordDecl *BaseRecord = cast<CXXRecordDecl>(BaseRT->getDecl()); 713 if (!BaseRecord->isDefinition() || 714 !IsFullyFormedScope(SemaRef, BaseRecord)) 715 return false; 716 } 717 718 return true; 719} 720 721/// Determines whether we can lookup this id-expression now or whether 722/// we have to wait until template instantiation is complete. 723static bool IsDependentIdExpression(Sema &SemaRef, const CXXScopeSpec &SS) { 724 DeclContext *DC = SemaRef.computeDeclContext(SS, false); 725 726 // If the qualifier scope isn't computable, it's definitely dependent. 727 if (!DC) return true; 728 729 // If the qualifier scope doesn't name a record, we can always look into it. 730 if (!isa<CXXRecordDecl>(DC)) return false; 731 732 // We can't look into record types unless they're fully-formed. 733 if (!IsFullyFormedScope(SemaRef, cast<CXXRecordDecl>(DC))) return true; 734 735 return false; 736} 737 738/// Determines if the given class is provably not derived from all of 739/// the prospective base classes. 740static bool IsProvablyNotDerivedFrom(Sema &SemaRef, 741 CXXRecordDecl *Record, 742 const llvm::SmallPtrSet<CXXRecordDecl*, 4> &Bases) { 743 if (Bases.count(Record->getCanonicalDecl())) 744 return false; 745 746 RecordDecl *RD = Record->getDefinition(SemaRef.Context); 747 if (!RD) return false; 748 Record = cast<CXXRecordDecl>(RD); 749 750 for (CXXRecordDecl::base_class_iterator I = Record->bases_begin(), 751 E = Record->bases_end(); I != E; ++I) { 752 CanQualType BaseT = SemaRef.Context.getCanonicalType((*I).getType()); 753 CanQual<RecordType> BaseRT = BaseT->getAs<RecordType>(); 754 if (!BaseRT) return false; 755 756 CXXRecordDecl *BaseRecord = cast<CXXRecordDecl>(BaseRT->getDecl()); 757 if (!IsProvablyNotDerivedFrom(SemaRef, BaseRecord, Bases)) 758 return false; 759 } 760 761 return true; 762} 763 764/// Determines if this a C++ class member. 765static bool IsClassMember(NamedDecl *D) { 766 DeclContext *DC = D->getDeclContext(); 767 768 // C++0x [class.mem]p1: 769 // The enumerators of an unscoped enumeration defined in 770 // the class are members of the class. 771 // FIXME: support C++0x scoped enumerations. 772 if (isa<EnumDecl>(DC)) 773 DC = DC->getParent(); 774 775 return DC->isRecord(); 776} 777 778/// Determines if this is an instance member of a class. 779static bool IsInstanceMember(NamedDecl *D) { 780 assert(IsClassMember(D) && 781 "checking whether non-member is instance member"); 782 783 if (isa<FieldDecl>(D)) return true; 784 785 if (isa<CXXMethodDecl>(D)) 786 return !cast<CXXMethodDecl>(D)->isStatic(); 787 788 if (isa<FunctionTemplateDecl>(D)) { 789 D = cast<FunctionTemplateDecl>(D)->getTemplatedDecl(); 790 return !cast<CXXMethodDecl>(D)->isStatic(); 791 } 792 793 return false; 794} 795 796enum IMAKind { 797 /// The reference is definitely not an instance member access. 798 IMA_Static, 799 800 /// The reference may be an implicit instance member access. 801 IMA_Mixed, 802 803 /// The reference may be to an instance member, but it is invalid if 804 /// so, because the context is not an instance method. 805 IMA_Mixed_StaticContext, 806 807 /// The reference may be to an instance member, but it is invalid if 808 /// so, because the context is from an unrelated class. 809 IMA_Mixed_Unrelated, 810 811 /// The reference is definitely an implicit instance member access. 812 IMA_Instance, 813 814 /// The reference may be to an unresolved using declaration. 815 IMA_Unresolved, 816 817 /// The reference may be to an unresolved using declaration and the 818 /// context is not an instance method. 819 IMA_Unresolved_StaticContext, 820 821 /// The reference is to a member of an anonymous structure in a 822 /// non-class context. 823 IMA_AnonymousMember, 824 825 /// All possible referrents are instance members and the current 826 /// context is not an instance method. 827 IMA_Error_StaticContext, 828 829 /// All possible referrents are instance members of an unrelated 830 /// class. 831 IMA_Error_Unrelated 832}; 833 834/// The given lookup names class member(s) and is not being used for 835/// an address-of-member expression. Classify the type of access 836/// according to whether it's possible that this reference names an 837/// instance member. This is best-effort; it is okay to 838/// conservatively answer "yes", in which case some errors will simply 839/// not be caught until template-instantiation. 840static IMAKind ClassifyImplicitMemberAccess(Sema &SemaRef, 841 const LookupResult &R) { 842 assert(!R.empty() && IsClassMember(*R.begin())); 843 844 bool isStaticContext = 845 (!isa<CXXMethodDecl>(SemaRef.CurContext) || 846 cast<CXXMethodDecl>(SemaRef.CurContext)->isStatic()); 847 848 if (R.isUnresolvableResult()) 849 return isStaticContext ? IMA_Unresolved_StaticContext : IMA_Unresolved; 850 851 // Collect all the declaring classes of instance members we find. 852 bool hasNonInstance = false; 853 llvm::SmallPtrSet<CXXRecordDecl*, 4> Classes; 854 for (LookupResult::iterator I = R.begin(), E = R.end(); I != E; ++I) { 855 NamedDecl *D = (*I)->getUnderlyingDecl(); 856 if (IsInstanceMember(D)) { 857 CXXRecordDecl *R = cast<CXXRecordDecl>(D->getDeclContext()); 858 859 // If this is a member of an anonymous record, move out to the 860 // innermost non-anonymous struct or union. If there isn't one, 861 // that's a special case. 862 while (R->isAnonymousStructOrUnion()) { 863 R = dyn_cast<CXXRecordDecl>(R->getParent()); 864 if (!R) return IMA_AnonymousMember; 865 } 866 Classes.insert(R->getCanonicalDecl()); 867 } 868 else 869 hasNonInstance = true; 870 } 871 872 // If we didn't find any instance members, it can't be an implicit 873 // member reference. 874 if (Classes.empty()) 875 return IMA_Static; 876 877 // If the current context is not an instance method, it can't be 878 // an implicit member reference. 879 if (isStaticContext) 880 return (hasNonInstance ? IMA_Mixed_StaticContext : IMA_Error_StaticContext); 881 882 // If we can prove that the current context is unrelated to all the 883 // declaring classes, it can't be an implicit member reference (in 884 // which case it's an error if any of those members are selected). 885 if (IsProvablyNotDerivedFrom(SemaRef, 886 cast<CXXMethodDecl>(SemaRef.CurContext)->getParent(), 887 Classes)) 888 return (hasNonInstance ? IMA_Mixed_Unrelated : IMA_Error_Unrelated); 889 890 return (hasNonInstance ? IMA_Mixed : IMA_Instance); 891} 892 893/// Diagnose a reference to a field with no object available. 894static void DiagnoseInstanceReference(Sema &SemaRef, 895 const CXXScopeSpec &SS, 896 const LookupResult &R) { 897 SourceLocation Loc = R.getNameLoc(); 898 SourceRange Range(Loc); 899 if (SS.isSet()) Range.setBegin(SS.getRange().getBegin()); 900 901 if (R.getAsSingle<FieldDecl>()) { 902 if (CXXMethodDecl *MD = dyn_cast<CXXMethodDecl>(SemaRef.CurContext)) { 903 if (MD->isStatic()) { 904 // "invalid use of member 'x' in static member function" 905 SemaRef.Diag(Loc, diag::err_invalid_member_use_in_static_method) 906 << Range << R.getLookupName(); 907 return; 908 } 909 } 910 911 SemaRef.Diag(Loc, diag::err_invalid_non_static_member_use) 912 << R.getLookupName() << Range; 913 return; 914 } 915 916 SemaRef.Diag(Loc, diag::err_member_call_without_object) << Range; 917} 918 919Sema::OwningExprResult Sema::ActOnIdExpression(Scope *S, 920 const CXXScopeSpec &SS, 921 UnqualifiedId &Id, 922 bool HasTrailingLParen, 923 bool isAddressOfOperand) { 924 assert(!(isAddressOfOperand && HasTrailingLParen) && 925 "cannot be direct & operand and have a trailing lparen"); 926 927 if (SS.isInvalid()) 928 return ExprError(); 929 930 TemplateArgumentListInfo TemplateArgsBuffer; 931 932 // Decompose the UnqualifiedId into the following data. 933 DeclarationName Name; 934 SourceLocation NameLoc; 935 const TemplateArgumentListInfo *TemplateArgs; 936 DecomposeUnqualifiedId(*this, Id, TemplateArgsBuffer, 937 Name, NameLoc, TemplateArgs); 938 939 IdentifierInfo *II = Name.getAsIdentifierInfo(); 940 941 // C++ [temp.dep.expr]p3: 942 // An id-expression is type-dependent if it contains: 943 // -- a nested-name-specifier that contains a class-name that 944 // names a dependent type. 945 // Determine whether this is a member of an unknown specialization; 946 // we need to handle these differently. 947 if (SS.isSet() && IsDependentIdExpression(*this, SS)) { 948 return ActOnDependentIdExpression(SS, Name, NameLoc, 949 isAddressOfOperand, 950 TemplateArgs); 951 } 952 953 // Perform the required lookup. 954 LookupResult R(*this, Name, NameLoc, LookupOrdinaryName); 955 if (TemplateArgs) { 956 // Just re-use the lookup done by isTemplateName. 957 DecomposeTemplateName(R, Id); 958 } else { 959 LookupParsedName(R, S, &SS, true); 960 961 // If this reference is in an Objective-C method, then we need to do 962 // some special Objective-C lookup, too. 963 if (!SS.isSet() && II && getCurMethodDecl()) { 964 OwningExprResult E(LookupInObjCMethod(R, S, II)); 965 if (E.isInvalid()) 966 return ExprError(); 967 968 Expr *Ex = E.takeAs<Expr>(); 969 if (Ex) return Owned(Ex); 970 } 971 } 972 973 if (R.isAmbiguous()) 974 return ExprError(); 975 976 // Determine whether this name might be a candidate for 977 // argument-dependent lookup. 978 bool ADL = UseArgumentDependentLookup(SS, R, HasTrailingLParen); 979 980 if (R.empty() && !ADL) { 981 // Otherwise, this could be an implicitly declared function reference (legal 982 // in C90, extension in C99, forbidden in C++). 983 if (HasTrailingLParen && II && !getLangOptions().CPlusPlus) { 984 NamedDecl *D = ImplicitlyDefineFunction(NameLoc, *II, S); 985 if (D) R.addDecl(D); 986 } 987 988 // If this name wasn't predeclared and if this is not a function 989 // call, diagnose the problem. 990 if (R.empty()) { 991 if (!SS.isEmpty()) 992 return ExprError(Diag(NameLoc, diag::err_no_member) 993 << Name << computeDeclContext(SS, false) 994 << SS.getRange()); 995 else if (Name.getNameKind() == DeclarationName::CXXOperatorName || 996 Name.getNameKind() == DeclarationName::CXXLiteralOperatorName || 997 Name.getNameKind() == DeclarationName::CXXConversionFunctionName) 998 return ExprError(Diag(NameLoc, diag::err_undeclared_use) 999 << Name); 1000 else 1001 return ExprError(Diag(NameLoc, diag::err_undeclared_var_use) << Name); 1002 } 1003 } 1004 1005 // This is guaranteed from this point on. 1006 assert(!R.empty() || ADL); 1007 1008 if (VarDecl *Var = R.getAsSingle<VarDecl>()) { 1009 // Warn about constructs like: 1010 // if (void *X = foo()) { ... } else { X }. 1011 // In the else block, the pointer is always false. 1012 1013 if (Var->isDeclaredInCondition() && Var->getType()->isScalarType()) { 1014 Scope *CheckS = S; 1015 while (CheckS && CheckS->getControlParent()) { 1016 if (CheckS->isWithinElse() && 1017 CheckS->getControlParent()->isDeclScope(DeclPtrTy::make(Var))) { 1018 ExprError(Diag(NameLoc, diag::warn_value_always_zero) 1019 << Var->getDeclName() 1020 << (Var->getType()->isPointerType()? 2 : 1021 Var->getType()->isBooleanType()? 1 : 0)); 1022 break; 1023 } 1024 1025 // Move to the parent of this scope. 1026 CheckS = CheckS->getParent(); 1027 } 1028 } 1029 } else if (FunctionDecl *Func = R.getAsSingle<FunctionDecl>()) { 1030 if (!getLangOptions().CPlusPlus && !Func->hasPrototype()) { 1031 // C99 DR 316 says that, if a function type comes from a 1032 // function definition (without a prototype), that type is only 1033 // used for checking compatibility. Therefore, when referencing 1034 // the function, we pretend that we don't have the full function 1035 // type. 1036 if (DiagnoseUseOfDecl(Func, NameLoc)) 1037 return ExprError(); 1038 1039 QualType T = Func->getType(); 1040 QualType NoProtoType = T; 1041 if (const FunctionProtoType *Proto = T->getAs<FunctionProtoType>()) 1042 NoProtoType = Context.getFunctionNoProtoType(Proto->getResultType()); 1043 return BuildDeclRefExpr(Func, NoProtoType, NameLoc, &SS); 1044 } 1045 } 1046 1047 // Check whether this might be a C++ implicit instance member access. 1048 // C++ [expr.prim.general]p6: 1049 // Within the definition of a non-static member function, an 1050 // identifier that names a non-static member is transformed to a 1051 // class member access expression. 1052 // But note that &SomeClass::foo is grammatically distinct, even 1053 // though we don't parse it that way. 1054 if (!R.empty() && IsClassMember(*R.begin())) { 1055 bool isAbstractMemberPointer = (isAddressOfOperand && !SS.isEmpty()); 1056 1057 if (!isAbstractMemberPointer) { 1058 switch (ClassifyImplicitMemberAccess(*this, R)) { 1059 case IMA_Instance: 1060 return BuildImplicitMemberExpr(SS, R, TemplateArgs, true); 1061 1062 case IMA_AnonymousMember: 1063 assert(R.isSingleResult()); 1064 return BuildAnonymousStructUnionMemberReference(R.getNameLoc(), 1065 R.getAsSingle<FieldDecl>()); 1066 1067 case IMA_Mixed: 1068 case IMA_Mixed_Unrelated: 1069 case IMA_Unresolved: 1070 return BuildImplicitMemberExpr(SS, R, TemplateArgs, false); 1071 1072 case IMA_Static: 1073 case IMA_Mixed_StaticContext: 1074 case IMA_Unresolved_StaticContext: 1075 break; 1076 1077 case IMA_Error_StaticContext: 1078 case IMA_Error_Unrelated: 1079 DiagnoseInstanceReference(*this, SS, R); 1080 return ExprError(); 1081 } 1082 } 1083 } 1084 1085 if (TemplateArgs) 1086 return BuildTemplateIdExpr(SS, R, ADL, *TemplateArgs); 1087 1088 return BuildDeclarationNameExpr(SS, R, ADL); 1089} 1090 1091/// BuildQualifiedDeclarationNameExpr - Build a C++ qualified 1092/// declaration name, generally during template instantiation. 1093/// There's a large number of things which don't need to be done along 1094/// this path. 1095Sema::OwningExprResult 1096Sema::BuildQualifiedDeclarationNameExpr(const CXXScopeSpec &SS, 1097 DeclarationName Name, 1098 SourceLocation NameLoc) { 1099 DeclContext *DC; 1100 if (!(DC = computeDeclContext(SS, false)) || 1101 DC->isDependentContext() || 1102 RequireCompleteDeclContext(SS)) 1103 return BuildDependentDeclRefExpr(SS, Name, NameLoc, 0); 1104 1105 LookupResult R(*this, Name, NameLoc, LookupOrdinaryName); 1106 LookupQualifiedName(R, DC); 1107 1108 if (R.isAmbiguous()) 1109 return ExprError(); 1110 1111 if (R.empty()) { 1112 Diag(NameLoc, diag::err_no_member) << Name << DC << SS.getRange(); 1113 return ExprError(); 1114 } 1115 1116 return BuildDeclarationNameExpr(SS, R, /*ADL*/ false); 1117} 1118 1119/// LookupInObjCMethod - The parser has read a name in, and Sema has 1120/// detected that we're currently inside an ObjC method. Perform some 1121/// additional lookup. 1122/// 1123/// Ideally, most of this would be done by lookup, but there's 1124/// actually quite a lot of extra work involved. 1125/// 1126/// Returns a null sentinel to indicate trivial success. 1127Sema::OwningExprResult 1128Sema::LookupInObjCMethod(LookupResult &Lookup, Scope *S, 1129 IdentifierInfo *II) { 1130 SourceLocation Loc = Lookup.getNameLoc(); 1131 1132 // There are two cases to handle here. 1) scoped lookup could have failed, 1133 // in which case we should look for an ivar. 2) scoped lookup could have 1134 // found a decl, but that decl is outside the current instance method (i.e. 1135 // a global variable). In these two cases, we do a lookup for an ivar with 1136 // this name, if the lookup sucedes, we replace it our current decl. 1137 1138 // If we're in a class method, we don't normally want to look for 1139 // ivars. But if we don't find anything else, and there's an 1140 // ivar, that's an error. 1141 bool IsClassMethod = getCurMethodDecl()->isClassMethod(); 1142 1143 bool LookForIvars; 1144 if (Lookup.empty()) 1145 LookForIvars = true; 1146 else if (IsClassMethod) 1147 LookForIvars = false; 1148 else 1149 LookForIvars = (Lookup.isSingleResult() && 1150 Lookup.getFoundDecl()->isDefinedOutsideFunctionOrMethod()); 1151 1152 if (LookForIvars) { 1153 ObjCInterfaceDecl *IFace = getCurMethodDecl()->getClassInterface(); 1154 ObjCInterfaceDecl *ClassDeclared; 1155 if (ObjCIvarDecl *IV = IFace->lookupInstanceVariable(II, ClassDeclared)) { 1156 // Diagnose using an ivar in a class method. 1157 if (IsClassMethod) 1158 return ExprError(Diag(Loc, diag::error_ivar_use_in_class_method) 1159 << IV->getDeclName()); 1160 1161 // If we're referencing an invalid decl, just return this as a silent 1162 // error node. The error diagnostic was already emitted on the decl. 1163 if (IV->isInvalidDecl()) 1164 return ExprError(); 1165 1166 // Check if referencing a field with __attribute__((deprecated)). 1167 if (DiagnoseUseOfDecl(IV, Loc)) 1168 return ExprError(); 1169 1170 // Diagnose the use of an ivar outside of the declaring class. 1171 if (IV->getAccessControl() == ObjCIvarDecl::Private && 1172 ClassDeclared != IFace) 1173 Diag(Loc, diag::error_private_ivar_access) << IV->getDeclName(); 1174 1175 // FIXME: This should use a new expr for a direct reference, don't 1176 // turn this into Self->ivar, just return a BareIVarExpr or something. 1177 IdentifierInfo &II = Context.Idents.get("self"); 1178 UnqualifiedId SelfName; 1179 SelfName.setIdentifier(&II, SourceLocation()); 1180 CXXScopeSpec SelfScopeSpec; 1181 OwningExprResult SelfExpr = ActOnIdExpression(S, SelfScopeSpec, 1182 SelfName, false, false); 1183 MarkDeclarationReferenced(Loc, IV); 1184 return Owned(new (Context) 1185 ObjCIvarRefExpr(IV, IV->getType(), Loc, 1186 SelfExpr.takeAs<Expr>(), true, true)); 1187 } 1188 } else if (getCurMethodDecl()->isInstanceMethod()) { 1189 // We should warn if a local variable hides an ivar. 1190 ObjCInterfaceDecl *IFace = getCurMethodDecl()->getClassInterface(); 1191 ObjCInterfaceDecl *ClassDeclared; 1192 if (ObjCIvarDecl *IV = IFace->lookupInstanceVariable(II, ClassDeclared)) { 1193 if (IV->getAccessControl() != ObjCIvarDecl::Private || 1194 IFace == ClassDeclared) 1195 Diag(Loc, diag::warn_ivar_use_hidden) << IV->getDeclName(); 1196 } 1197 } 1198 1199 // Needed to implement property "super.method" notation. 1200 if (Lookup.empty() && II->isStr("super")) { 1201 QualType T; 1202 1203 if (getCurMethodDecl()->isInstanceMethod()) 1204 T = Context.getObjCObjectPointerType(Context.getObjCInterfaceType( 1205 getCurMethodDecl()->getClassInterface())); 1206 else 1207 T = Context.getObjCClassType(); 1208 return Owned(new (Context) ObjCSuperExpr(Loc, T)); 1209 } 1210 1211 // Sentinel value saying that we didn't do anything special. 1212 return Owned((Expr*) 0); 1213} 1214 1215/// \brief Cast member's object to its own class if necessary. 1216bool 1217Sema::PerformObjectMemberConversion(Expr *&From, NamedDecl *Member) { 1218 if (FieldDecl *FD = dyn_cast<FieldDecl>(Member)) 1219 if (CXXRecordDecl *RD = 1220 dyn_cast<CXXRecordDecl>(FD->getDeclContext())) { 1221 QualType DestType = 1222 Context.getCanonicalType(Context.getTypeDeclType(RD)); 1223 if (DestType->isDependentType() || From->getType()->isDependentType()) 1224 return false; 1225 QualType FromRecordType = From->getType(); 1226 QualType DestRecordType = DestType; 1227 if (FromRecordType->getAs<PointerType>()) { 1228 DestType = Context.getPointerType(DestType); 1229 FromRecordType = FromRecordType->getPointeeType(); 1230 } 1231 if (!Context.hasSameUnqualifiedType(FromRecordType, DestRecordType) && 1232 CheckDerivedToBaseConversion(FromRecordType, 1233 DestRecordType, 1234 From->getSourceRange().getBegin(), 1235 From->getSourceRange())) 1236 return true; 1237 ImpCastExprToType(From, DestType, CastExpr::CK_DerivedToBase, 1238 /*isLvalue=*/true); 1239 } 1240 return false; 1241} 1242 1243/// \brief Build a MemberExpr AST node. 1244static MemberExpr *BuildMemberExpr(ASTContext &C, Expr *Base, bool isArrow, 1245 const CXXScopeSpec &SS, ValueDecl *Member, 1246 SourceLocation Loc, QualType Ty, 1247 const TemplateArgumentListInfo *TemplateArgs = 0) { 1248 NestedNameSpecifier *Qualifier = 0; 1249 SourceRange QualifierRange; 1250 if (SS.isSet()) { 1251 Qualifier = (NestedNameSpecifier *) SS.getScopeRep(); 1252 QualifierRange = SS.getRange(); 1253 } 1254 1255 return MemberExpr::Create(C, Base, isArrow, Qualifier, QualifierRange, 1256 Member, Loc, TemplateArgs, Ty); 1257} 1258 1259/// Builds an implicit member access expression. The current context 1260/// is known to be an instance method, and the given unqualified lookup 1261/// set is known to contain only instance members, at least one of which 1262/// is from an appropriate type. 1263Sema::OwningExprResult 1264Sema::BuildImplicitMemberExpr(const CXXScopeSpec &SS, 1265 LookupResult &R, 1266 const TemplateArgumentListInfo *TemplateArgs, 1267 bool IsKnownInstance) { 1268 assert(!R.empty() && !R.isAmbiguous()); 1269 1270 SourceLocation Loc = R.getNameLoc(); 1271 1272 // We may have found a field within an anonymous union or struct 1273 // (C++ [class.union]). 1274 // FIXME: This needs to happen post-isImplicitMemberReference? 1275 // FIXME: template-ids inside anonymous structs? 1276 if (FieldDecl *FD = R.getAsSingle<FieldDecl>()) 1277 if (cast<RecordDecl>(FD->getDeclContext())->isAnonymousStructOrUnion()) 1278 return BuildAnonymousStructUnionMemberReference(Loc, FD); 1279 1280 // If this is known to be an instance access, go ahead and build a 1281 // 'this' expression now. 1282 QualType ThisType = cast<CXXMethodDecl>(CurContext)->getThisType(Context); 1283 Expr *This = 0; // null signifies implicit access 1284 if (IsKnownInstance) { 1285 This = new (Context) CXXThisExpr(SourceLocation(), ThisType); 1286 } 1287 1288 return BuildMemberReferenceExpr(ExprArg(*this, This), ThisType, 1289 /*OpLoc*/ SourceLocation(), 1290 /*IsArrow*/ true, 1291 SS, R, TemplateArgs); 1292} 1293 1294bool Sema::UseArgumentDependentLookup(const CXXScopeSpec &SS, 1295 const LookupResult &R, 1296 bool HasTrailingLParen) { 1297 // Only when used directly as the postfix-expression of a call. 1298 if (!HasTrailingLParen) 1299 return false; 1300 1301 // Never if a scope specifier was provided. 1302 if (SS.isSet()) 1303 return false; 1304 1305 // Only in C++ or ObjC++. 1306 if (!getLangOptions().CPlusPlus) 1307 return false; 1308 1309 // Turn off ADL when we find certain kinds of declarations during 1310 // normal lookup: 1311 for (LookupResult::iterator I = R.begin(), E = R.end(); I != E; ++I) { 1312 NamedDecl *D = *I; 1313 1314 // C++0x [basic.lookup.argdep]p3: 1315 // -- a declaration of a class member 1316 // Since using decls preserve this property, we check this on the 1317 // original decl. 1318 if (IsClassMember(D)) 1319 return false; 1320 1321 // C++0x [basic.lookup.argdep]p3: 1322 // -- a block-scope function declaration that is not a 1323 // using-declaration 1324 // NOTE: we also trigger this for function templates (in fact, we 1325 // don't check the decl type at all, since all other decl types 1326 // turn off ADL anyway). 1327 if (isa<UsingShadowDecl>(D)) 1328 D = cast<UsingShadowDecl>(D)->getTargetDecl(); 1329 else if (D->getDeclContext()->isFunctionOrMethod()) 1330 return false; 1331 1332 // C++0x [basic.lookup.argdep]p3: 1333 // -- a declaration that is neither a function or a function 1334 // template 1335 // And also for builtin functions. 1336 if (isa<FunctionDecl>(D)) { 1337 FunctionDecl *FDecl = cast<FunctionDecl>(D); 1338 1339 // But also builtin functions. 1340 if (FDecl->getBuiltinID() && FDecl->isImplicit()) 1341 return false; 1342 } else if (!isa<FunctionTemplateDecl>(D)) 1343 return false; 1344 } 1345 1346 return true; 1347} 1348 1349 1350/// Diagnoses obvious problems with the use of the given declaration 1351/// as an expression. This is only actually called for lookups that 1352/// were not overloaded, and it doesn't promise that the declaration 1353/// will in fact be used. 1354static bool CheckDeclInExpr(Sema &S, SourceLocation Loc, NamedDecl *D) { 1355 if (isa<TypedefDecl>(D)) { 1356 S.Diag(Loc, diag::err_unexpected_typedef) << D->getDeclName(); 1357 return true; 1358 } 1359 1360 if (isa<ObjCInterfaceDecl>(D)) { 1361 S.Diag(Loc, diag::err_unexpected_interface) << D->getDeclName(); 1362 return true; 1363 } 1364 1365 if (isa<NamespaceDecl>(D)) { 1366 S.Diag(Loc, diag::err_unexpected_namespace) << D->getDeclName(); 1367 return true; 1368 } 1369 1370 return false; 1371} 1372 1373Sema::OwningExprResult 1374Sema::BuildDeclarationNameExpr(const CXXScopeSpec &SS, 1375 LookupResult &R, 1376 bool NeedsADL) { 1377 // If this is a single, fully-resolved result and we don't need ADL, 1378 // just build an ordinary singleton decl ref. 1379 if (!NeedsADL && R.isSingleResult()) 1380 return BuildDeclarationNameExpr(SS, R.getNameLoc(), R.getFoundDecl()); 1381 1382 // We only need to check the declaration if there's exactly one 1383 // result, because in the overloaded case the results can only be 1384 // functions and function templates. 1385 if (R.isSingleResult() && 1386 CheckDeclInExpr(*this, R.getNameLoc(), R.getFoundDecl())) 1387 return ExprError(); 1388 1389 bool Dependent 1390 = UnresolvedLookupExpr::ComputeDependence(R.begin(), R.end(), 0); 1391 UnresolvedLookupExpr *ULE 1392 = UnresolvedLookupExpr::Create(Context, Dependent, 1393 (NestedNameSpecifier*) SS.getScopeRep(), 1394 SS.getRange(), 1395 R.getLookupName(), R.getNameLoc(), 1396 NeedsADL, R.isOverloadedResult()); 1397 for (LookupResult::iterator I = R.begin(), E = R.end(); I != E; ++I) 1398 ULE->addDecl(*I); 1399 1400 return Owned(ULE); 1401} 1402 1403 1404/// \brief Complete semantic analysis for a reference to the given declaration. 1405Sema::OwningExprResult 1406Sema::BuildDeclarationNameExpr(const CXXScopeSpec &SS, 1407 SourceLocation Loc, NamedDecl *D) { 1408 assert(D && "Cannot refer to a NULL declaration"); 1409 assert(!isa<FunctionTemplateDecl>(D) && 1410 "Cannot refer unambiguously to a function template"); 1411 DeclarationName Name = D->getDeclName(); 1412 1413 if (CheckDeclInExpr(*this, Loc, D)) 1414 return ExprError(); 1415 1416 if (TemplateDecl *Template = dyn_cast<TemplateDecl>(D)) { 1417 // Specifically diagnose references to class templates that are missing 1418 // a template argument list. 1419 Diag(Loc, diag::err_template_decl_ref) 1420 << Template << SS.getRange(); 1421 Diag(Template->getLocation(), diag::note_template_decl_here); 1422 return ExprError(); 1423 } 1424 1425 // Make sure that we're referring to a value. 1426 ValueDecl *VD = dyn_cast<ValueDecl>(D); 1427 if (!VD) { 1428 Diag(Loc, diag::err_ref_non_value) 1429 << D << SS.getRange(); 1430 Diag(D->getLocation(), diag::note_previous_declaration); 1431 return ExprError(); 1432 } 1433 1434 // Check whether this declaration can be used. Note that we suppress 1435 // this check when we're going to perform argument-dependent lookup 1436 // on this function name, because this might not be the function 1437 // that overload resolution actually selects. 1438 if (DiagnoseUseOfDecl(VD, Loc)) 1439 return ExprError(); 1440 1441 // Only create DeclRefExpr's for valid Decl's. 1442 if (VD->isInvalidDecl()) 1443 return ExprError(); 1444 1445 // If the identifier reference is inside a block, and it refers to a value 1446 // that is outside the block, create a BlockDeclRefExpr instead of a 1447 // DeclRefExpr. This ensures the value is treated as a copy-in snapshot when 1448 // the block is formed. 1449 // 1450 // We do not do this for things like enum constants, global variables, etc, 1451 // as they do not get snapshotted. 1452 // 1453 if (CurBlock && ShouldSnapshotBlockValueReference(CurBlock, VD)) { 1454 MarkDeclarationReferenced(Loc, VD); 1455 QualType ExprTy = VD->getType().getNonReferenceType(); 1456 // The BlocksAttr indicates the variable is bound by-reference. 1457 if (VD->getAttr<BlocksAttr>()) 1458 return Owned(new (Context) BlockDeclRefExpr(VD, ExprTy, Loc, true)); 1459 // This is to record that a 'const' was actually synthesize and added. 1460 bool constAdded = !ExprTy.isConstQualified(); 1461 // Variable will be bound by-copy, make it const within the closure. 1462 1463 ExprTy.addConst(); 1464 return Owned(new (Context) BlockDeclRefExpr(VD, ExprTy, Loc, false, 1465 constAdded)); 1466 } 1467 // If this reference is not in a block or if the referenced variable is 1468 // within the block, create a normal DeclRefExpr. 1469 1470 return BuildDeclRefExpr(VD, VD->getType().getNonReferenceType(), Loc, &SS); 1471} 1472 1473Sema::OwningExprResult Sema::ActOnPredefinedExpr(SourceLocation Loc, 1474 tok::TokenKind Kind) { 1475 PredefinedExpr::IdentType IT; 1476 1477 switch (Kind) { 1478 default: assert(0 && "Unknown simple primary expr!"); 1479 case tok::kw___func__: IT = PredefinedExpr::Func; break; // [C99 6.4.2.2] 1480 case tok::kw___FUNCTION__: IT = PredefinedExpr::Function; break; 1481 case tok::kw___PRETTY_FUNCTION__: IT = PredefinedExpr::PrettyFunction; break; 1482 } 1483 1484 // Pre-defined identifiers are of type char[x], where x is the length of the 1485 // string. 1486 1487 Decl *currentDecl = getCurFunctionOrMethodDecl(); 1488 if (!currentDecl) { 1489 Diag(Loc, diag::ext_predef_outside_function); 1490 currentDecl = Context.getTranslationUnitDecl(); 1491 } 1492 1493 QualType ResTy; 1494 if (cast<DeclContext>(currentDecl)->isDependentContext()) { 1495 ResTy = Context.DependentTy; 1496 } else { 1497 unsigned Length = 1498 PredefinedExpr::ComputeName(Context, IT, currentDecl).length(); 1499 1500 llvm::APInt LengthI(32, Length + 1); 1501 ResTy = Context.CharTy.withConst(); 1502 ResTy = Context.getConstantArrayType(ResTy, LengthI, ArrayType::Normal, 0); 1503 } 1504 return Owned(new (Context) PredefinedExpr(Loc, ResTy, IT)); 1505} 1506 1507Sema::OwningExprResult Sema::ActOnCharacterConstant(const Token &Tok) { 1508 llvm::SmallString<16> CharBuffer; 1509 CharBuffer.resize(Tok.getLength()); 1510 const char *ThisTokBegin = &CharBuffer[0]; 1511 unsigned ActualLength = PP.getSpelling(Tok, ThisTokBegin); 1512 1513 CharLiteralParser Literal(ThisTokBegin, ThisTokBegin+ActualLength, 1514 Tok.getLocation(), PP); 1515 if (Literal.hadError()) 1516 return ExprError(); 1517 1518 QualType type = getLangOptions().CPlusPlus ? Context.CharTy : Context.IntTy; 1519 1520 return Owned(new (Context) CharacterLiteral(Literal.getValue(), 1521 Literal.isWide(), 1522 type, Tok.getLocation())); 1523} 1524 1525Action::OwningExprResult Sema::ActOnNumericConstant(const Token &Tok) { 1526 // Fast path for a single digit (which is quite common). A single digit 1527 // cannot have a trigraph, escaped newline, radix prefix, or type suffix. 1528 if (Tok.getLength() == 1) { 1529 const char Val = PP.getSpellingOfSingleCharacterNumericConstant(Tok); 1530 unsigned IntSize = Context.Target.getIntWidth(); 1531 return Owned(new (Context) IntegerLiteral(llvm::APInt(IntSize, Val-'0'), 1532 Context.IntTy, Tok.getLocation())); 1533 } 1534 1535 llvm::SmallString<512> IntegerBuffer; 1536 // Add padding so that NumericLiteralParser can overread by one character. 1537 IntegerBuffer.resize(Tok.getLength()+1); 1538 const char *ThisTokBegin = &IntegerBuffer[0]; 1539 1540 // Get the spelling of the token, which eliminates trigraphs, etc. 1541 unsigned ActualLength = PP.getSpelling(Tok, ThisTokBegin); 1542 1543 NumericLiteralParser Literal(ThisTokBegin, ThisTokBegin+ActualLength, 1544 Tok.getLocation(), PP); 1545 if (Literal.hadError) 1546 return ExprError(); 1547 1548 Expr *Res; 1549 1550 if (Literal.isFloatingLiteral()) { 1551 QualType Ty; 1552 if (Literal.isFloat) 1553 Ty = Context.FloatTy; 1554 else if (!Literal.isLong) 1555 Ty = Context.DoubleTy; 1556 else 1557 Ty = Context.LongDoubleTy; 1558 1559 const llvm::fltSemantics &Format = Context.getFloatTypeSemantics(Ty); 1560 1561 // isExact will be set by GetFloatValue(). 1562 bool isExact = false; 1563 llvm::APFloat Val = Literal.GetFloatValue(Format, &isExact); 1564 Res = new (Context) FloatingLiteral(Val, isExact, Ty, Tok.getLocation()); 1565 1566 } else if (!Literal.isIntegerLiteral()) { 1567 return ExprError(); 1568 } else { 1569 QualType Ty; 1570 1571 // long long is a C99 feature. 1572 if (!getLangOptions().C99 && !getLangOptions().CPlusPlus0x && 1573 Literal.isLongLong) 1574 Diag(Tok.getLocation(), diag::ext_longlong); 1575 1576 // Get the value in the widest-possible width. 1577 llvm::APInt ResultVal(Context.Target.getIntMaxTWidth(), 0); 1578 1579 if (Literal.GetIntegerValue(ResultVal)) { 1580 // If this value didn't fit into uintmax_t, warn and force to ull. 1581 Diag(Tok.getLocation(), diag::warn_integer_too_large); 1582 Ty = Context.UnsignedLongLongTy; 1583 assert(Context.getTypeSize(Ty) == ResultVal.getBitWidth() && 1584 "long long is not intmax_t?"); 1585 } else { 1586 // If this value fits into a ULL, try to figure out what else it fits into 1587 // according to the rules of C99 6.4.4.1p5. 1588 1589 // Octal, Hexadecimal, and integers with a U suffix are allowed to 1590 // be an unsigned int. 1591 bool AllowUnsigned = Literal.isUnsigned || Literal.getRadix() != 10; 1592 1593 // Check from smallest to largest, picking the smallest type we can. 1594 unsigned Width = 0; 1595 if (!Literal.isLong && !Literal.isLongLong) { 1596 // Are int/unsigned possibilities? 1597 unsigned IntSize = Context.Target.getIntWidth(); 1598 1599 // Does it fit in a unsigned int? 1600 if (ResultVal.isIntN(IntSize)) { 1601 // Does it fit in a signed int? 1602 if (!Literal.isUnsigned && ResultVal[IntSize-1] == 0) 1603 Ty = Context.IntTy; 1604 else if (AllowUnsigned) 1605 Ty = Context.UnsignedIntTy; 1606 Width = IntSize; 1607 } 1608 } 1609 1610 // Are long/unsigned long possibilities? 1611 if (Ty.isNull() && !Literal.isLongLong) { 1612 unsigned LongSize = Context.Target.getLongWidth(); 1613 1614 // Does it fit in a unsigned long? 1615 if (ResultVal.isIntN(LongSize)) { 1616 // Does it fit in a signed long? 1617 if (!Literal.isUnsigned && ResultVal[LongSize-1] == 0) 1618 Ty = Context.LongTy; 1619 else if (AllowUnsigned) 1620 Ty = Context.UnsignedLongTy; 1621 Width = LongSize; 1622 } 1623 } 1624 1625 // Finally, check long long if needed. 1626 if (Ty.isNull()) { 1627 unsigned LongLongSize = Context.Target.getLongLongWidth(); 1628 1629 // Does it fit in a unsigned long long? 1630 if (ResultVal.isIntN(LongLongSize)) { 1631 // Does it fit in a signed long long? 1632 if (!Literal.isUnsigned && ResultVal[LongLongSize-1] == 0) 1633 Ty = Context.LongLongTy; 1634 else if (AllowUnsigned) 1635 Ty = Context.UnsignedLongLongTy; 1636 Width = LongLongSize; 1637 } 1638 } 1639 1640 // If we still couldn't decide a type, we probably have something that 1641 // does not fit in a signed long long, but has no U suffix. 1642 if (Ty.isNull()) { 1643 Diag(Tok.getLocation(), diag::warn_integer_too_large_for_signed); 1644 Ty = Context.UnsignedLongLongTy; 1645 Width = Context.Target.getLongLongWidth(); 1646 } 1647 1648 if (ResultVal.getBitWidth() != Width) 1649 ResultVal.trunc(Width); 1650 } 1651 Res = new (Context) IntegerLiteral(ResultVal, Ty, Tok.getLocation()); 1652 } 1653 1654 // If this is an imaginary literal, create the ImaginaryLiteral wrapper. 1655 if (Literal.isImaginary) 1656 Res = new (Context) ImaginaryLiteral(Res, 1657 Context.getComplexType(Res->getType())); 1658 1659 return Owned(Res); 1660} 1661 1662Action::OwningExprResult Sema::ActOnParenExpr(SourceLocation L, 1663 SourceLocation R, ExprArg Val) { 1664 Expr *E = Val.takeAs<Expr>(); 1665 assert((E != 0) && "ActOnParenExpr() missing expr"); 1666 return Owned(new (Context) ParenExpr(L, R, E)); 1667} 1668 1669/// The UsualUnaryConversions() function is *not* called by this routine. 1670/// See C99 6.3.2.1p[2-4] for more details. 1671bool Sema::CheckSizeOfAlignOfOperand(QualType exprType, 1672 SourceLocation OpLoc, 1673 const SourceRange &ExprRange, 1674 bool isSizeof) { 1675 if (exprType->isDependentType()) 1676 return false; 1677 1678 // C++ [expr.sizeof]p2: "When applied to a reference or a reference type, 1679 // the result is the size of the referenced type." 1680 // C++ [expr.alignof]p3: "When alignof is applied to a reference type, the 1681 // result shall be the alignment of the referenced type." 1682 if (const ReferenceType *Ref = exprType->getAs<ReferenceType>()) 1683 exprType = Ref->getPointeeType(); 1684 1685 // C99 6.5.3.4p1: 1686 if (exprType->isFunctionType()) { 1687 // alignof(function) is allowed as an extension. 1688 if (isSizeof) 1689 Diag(OpLoc, diag::ext_sizeof_function_type) << ExprRange; 1690 return false; 1691 } 1692 1693 // Allow sizeof(void)/alignof(void) as an extension. 1694 if (exprType->isVoidType()) { 1695 Diag(OpLoc, diag::ext_sizeof_void_type) 1696 << (isSizeof ? "sizeof" : "__alignof") << ExprRange; 1697 return false; 1698 } 1699 1700 if (RequireCompleteType(OpLoc, exprType, 1701 PDiag(diag::err_sizeof_alignof_incomplete_type) 1702 << int(!isSizeof) << ExprRange)) 1703 return true; 1704 1705 // Reject sizeof(interface) and sizeof(interface<proto>) in 64-bit mode. 1706 if (LangOpts.ObjCNonFragileABI && exprType->isObjCInterfaceType()) { 1707 Diag(OpLoc, diag::err_sizeof_nonfragile_interface) 1708 << exprType << isSizeof << ExprRange; 1709 return true; 1710 } 1711 1712 return false; 1713} 1714 1715bool Sema::CheckAlignOfExpr(Expr *E, SourceLocation OpLoc, 1716 const SourceRange &ExprRange) { 1717 E = E->IgnoreParens(); 1718 1719 // alignof decl is always ok. 1720 if (isa<DeclRefExpr>(E)) 1721 return false; 1722 1723 // Cannot know anything else if the expression is dependent. 1724 if (E->isTypeDependent()) 1725 return false; 1726 1727 if (E->getBitField()) { 1728 Diag(OpLoc, diag::err_sizeof_alignof_bitfield) << 1 << ExprRange; 1729 return true; 1730 } 1731 1732 // Alignment of a field access is always okay, so long as it isn't a 1733 // bit-field. 1734 if (MemberExpr *ME = dyn_cast<MemberExpr>(E)) 1735 if (isa<FieldDecl>(ME->getMemberDecl())) 1736 return false; 1737 1738 return CheckSizeOfAlignOfOperand(E->getType(), OpLoc, ExprRange, false); 1739} 1740 1741/// \brief Build a sizeof or alignof expression given a type operand. 1742Action::OwningExprResult 1743Sema::CreateSizeOfAlignOfExpr(TypeSourceInfo *TInfo, 1744 SourceLocation OpLoc, 1745 bool isSizeOf, SourceRange R) { 1746 if (!TInfo) 1747 return ExprError(); 1748 1749 QualType T = TInfo->getType(); 1750 1751 if (!T->isDependentType() && 1752 CheckSizeOfAlignOfOperand(T, OpLoc, R, isSizeOf)) 1753 return ExprError(); 1754 1755 // C99 6.5.3.4p4: the type (an unsigned integer type) is size_t. 1756 return Owned(new (Context) SizeOfAlignOfExpr(isSizeOf, TInfo, 1757 Context.getSizeType(), OpLoc, 1758 R.getEnd())); 1759} 1760 1761/// \brief Build a sizeof or alignof expression given an expression 1762/// operand. 1763Action::OwningExprResult 1764Sema::CreateSizeOfAlignOfExpr(Expr *E, SourceLocation OpLoc, 1765 bool isSizeOf, SourceRange R) { 1766 // Verify that the operand is valid. 1767 bool isInvalid = false; 1768 if (E->isTypeDependent()) { 1769 // Delay type-checking for type-dependent expressions. 1770 } else if (!isSizeOf) { 1771 isInvalid = CheckAlignOfExpr(E, OpLoc, R); 1772 } else if (E->getBitField()) { // C99 6.5.3.4p1. 1773 Diag(OpLoc, diag::err_sizeof_alignof_bitfield) << 0; 1774 isInvalid = true; 1775 } else { 1776 isInvalid = CheckSizeOfAlignOfOperand(E->getType(), OpLoc, R, true); 1777 } 1778 1779 if (isInvalid) 1780 return ExprError(); 1781 1782 // C99 6.5.3.4p4: the type (an unsigned integer type) is size_t. 1783 return Owned(new (Context) SizeOfAlignOfExpr(isSizeOf, E, 1784 Context.getSizeType(), OpLoc, 1785 R.getEnd())); 1786} 1787 1788/// ActOnSizeOfAlignOfExpr - Handle @c sizeof(type) and @c sizeof @c expr and 1789/// the same for @c alignof and @c __alignof 1790/// Note that the ArgRange is invalid if isType is false. 1791Action::OwningExprResult 1792Sema::ActOnSizeOfAlignOfExpr(SourceLocation OpLoc, bool isSizeof, bool isType, 1793 void *TyOrEx, const SourceRange &ArgRange) { 1794 // If error parsing type, ignore. 1795 if (TyOrEx == 0) return ExprError(); 1796 1797 if (isType) { 1798 TypeSourceInfo *TInfo; 1799 (void) GetTypeFromParser(TyOrEx, &TInfo); 1800 return CreateSizeOfAlignOfExpr(TInfo, OpLoc, isSizeof, ArgRange); 1801 } 1802 1803 Expr *ArgEx = (Expr *)TyOrEx; 1804 Action::OwningExprResult Result 1805 = CreateSizeOfAlignOfExpr(ArgEx, OpLoc, isSizeof, ArgEx->getSourceRange()); 1806 1807 if (Result.isInvalid()) 1808 DeleteExpr(ArgEx); 1809 1810 return move(Result); 1811} 1812 1813QualType Sema::CheckRealImagOperand(Expr *&V, SourceLocation Loc, bool isReal) { 1814 if (V->isTypeDependent()) 1815 return Context.DependentTy; 1816 1817 // These operators return the element type of a complex type. 1818 if (const ComplexType *CT = V->getType()->getAs<ComplexType>()) 1819 return CT->getElementType(); 1820 1821 // Otherwise they pass through real integer and floating point types here. 1822 if (V->getType()->isArithmeticType()) 1823 return V->getType(); 1824 1825 // Reject anything else. 1826 Diag(Loc, diag::err_realimag_invalid_type) << V->getType() 1827 << (isReal ? "__real" : "__imag"); 1828 return QualType(); 1829} 1830 1831 1832 1833Action::OwningExprResult 1834Sema::ActOnPostfixUnaryOp(Scope *S, SourceLocation OpLoc, 1835 tok::TokenKind Kind, ExprArg Input) { 1836 UnaryOperator::Opcode Opc; 1837 switch (Kind) { 1838 default: assert(0 && "Unknown unary op!"); 1839 case tok::plusplus: Opc = UnaryOperator::PostInc; break; 1840 case tok::minusminus: Opc = UnaryOperator::PostDec; break; 1841 } 1842 1843 return BuildUnaryOp(S, OpLoc, Opc, move(Input)); 1844} 1845 1846Action::OwningExprResult 1847Sema::ActOnArraySubscriptExpr(Scope *S, ExprArg Base, SourceLocation LLoc, 1848 ExprArg Idx, SourceLocation RLoc) { 1849 // Since this might be a postfix expression, get rid of ParenListExprs. 1850 Base = MaybeConvertParenListExprToParenExpr(S, move(Base)); 1851 1852 Expr *LHSExp = static_cast<Expr*>(Base.get()), 1853 *RHSExp = static_cast<Expr*>(Idx.get()); 1854 1855 if (getLangOptions().CPlusPlus && 1856 (LHSExp->isTypeDependent() || RHSExp->isTypeDependent())) { 1857 Base.release(); 1858 Idx.release(); 1859 return Owned(new (Context) ArraySubscriptExpr(LHSExp, RHSExp, 1860 Context.DependentTy, RLoc)); 1861 } 1862 1863 if (getLangOptions().CPlusPlus && 1864 (LHSExp->getType()->isRecordType() || 1865 LHSExp->getType()->isEnumeralType() || 1866 RHSExp->getType()->isRecordType() || 1867 RHSExp->getType()->isEnumeralType())) { 1868 return CreateOverloadedArraySubscriptExpr(LLoc, RLoc, move(Base),move(Idx)); 1869 } 1870 1871 return CreateBuiltinArraySubscriptExpr(move(Base), LLoc, move(Idx), RLoc); 1872} 1873 1874 1875Action::OwningExprResult 1876Sema::CreateBuiltinArraySubscriptExpr(ExprArg Base, SourceLocation LLoc, 1877 ExprArg Idx, SourceLocation RLoc) { 1878 Expr *LHSExp = static_cast<Expr*>(Base.get()); 1879 Expr *RHSExp = static_cast<Expr*>(Idx.get()); 1880 1881 // Perform default conversions. 1882 DefaultFunctionArrayConversion(LHSExp); 1883 DefaultFunctionArrayConversion(RHSExp); 1884 1885 QualType LHSTy = LHSExp->getType(), RHSTy = RHSExp->getType(); 1886 1887 // C99 6.5.2.1p2: the expression e1[e2] is by definition precisely equivalent 1888 // to the expression *((e1)+(e2)). This means the array "Base" may actually be 1889 // in the subscript position. As a result, we need to derive the array base 1890 // and index from the expression types. 1891 Expr *BaseExpr, *IndexExpr; 1892 QualType ResultType; 1893 if (LHSTy->isDependentType() || RHSTy->isDependentType()) { 1894 BaseExpr = LHSExp; 1895 IndexExpr = RHSExp; 1896 ResultType = Context.DependentTy; 1897 } else if (const PointerType *PTy = LHSTy->getAs<PointerType>()) { 1898 BaseExpr = LHSExp; 1899 IndexExpr = RHSExp; 1900 ResultType = PTy->getPointeeType(); 1901 } else if (const PointerType *PTy = RHSTy->getAs<PointerType>()) { 1902 // Handle the uncommon case of "123[Ptr]". 1903 BaseExpr = RHSExp; 1904 IndexExpr = LHSExp; 1905 ResultType = PTy->getPointeeType(); 1906 } else if (const ObjCObjectPointerType *PTy = 1907 LHSTy->getAs<ObjCObjectPointerType>()) { 1908 BaseExpr = LHSExp; 1909 IndexExpr = RHSExp; 1910 ResultType = PTy->getPointeeType(); 1911 } else if (const ObjCObjectPointerType *PTy = 1912 RHSTy->getAs<ObjCObjectPointerType>()) { 1913 // Handle the uncommon case of "123[Ptr]". 1914 BaseExpr = RHSExp; 1915 IndexExpr = LHSExp; 1916 ResultType = PTy->getPointeeType(); 1917 } else if (const VectorType *VTy = LHSTy->getAs<VectorType>()) { 1918 BaseExpr = LHSExp; // vectors: V[123] 1919 IndexExpr = RHSExp; 1920 1921 // FIXME: need to deal with const... 1922 ResultType = VTy->getElementType(); 1923 } else if (LHSTy->isArrayType()) { 1924 // If we see an array that wasn't promoted by 1925 // DefaultFunctionArrayConversion, it must be an array that 1926 // wasn't promoted because of the C90 rule that doesn't 1927 // allow promoting non-lvalue arrays. Warn, then 1928 // force the promotion here. 1929 Diag(LHSExp->getLocStart(), diag::ext_subscript_non_lvalue) << 1930 LHSExp->getSourceRange(); 1931 ImpCastExprToType(LHSExp, Context.getArrayDecayedType(LHSTy), 1932 CastExpr::CK_ArrayToPointerDecay); 1933 LHSTy = LHSExp->getType(); 1934 1935 BaseExpr = LHSExp; 1936 IndexExpr = RHSExp; 1937 ResultType = LHSTy->getAs<PointerType>()->getPointeeType(); 1938 } else if (RHSTy->isArrayType()) { 1939 // Same as previous, except for 123[f().a] case 1940 Diag(RHSExp->getLocStart(), diag::ext_subscript_non_lvalue) << 1941 RHSExp->getSourceRange(); 1942 ImpCastExprToType(RHSExp, Context.getArrayDecayedType(RHSTy), 1943 CastExpr::CK_ArrayToPointerDecay); 1944 RHSTy = RHSExp->getType(); 1945 1946 BaseExpr = RHSExp; 1947 IndexExpr = LHSExp; 1948 ResultType = RHSTy->getAs<PointerType>()->getPointeeType(); 1949 } else { 1950 return ExprError(Diag(LLoc, diag::err_typecheck_subscript_value) 1951 << LHSExp->getSourceRange() << RHSExp->getSourceRange()); 1952 } 1953 // C99 6.5.2.1p1 1954 if (!(IndexExpr->getType()->isIntegerType() && 1955 IndexExpr->getType()->isScalarType()) && !IndexExpr->isTypeDependent()) 1956 return ExprError(Diag(LLoc, diag::err_typecheck_subscript_not_integer) 1957 << IndexExpr->getSourceRange()); 1958 1959 if ((IndexExpr->getType()->isSpecificBuiltinType(BuiltinType::Char_S) || 1960 IndexExpr->getType()->isSpecificBuiltinType(BuiltinType::Char_U)) 1961 && !IndexExpr->isTypeDependent()) 1962 Diag(LLoc, diag::warn_subscript_is_char) << IndexExpr->getSourceRange(); 1963 1964 // C99 6.5.2.1p1: "shall have type "pointer to *object* type". Similarly, 1965 // C++ [expr.sub]p1: The type "T" shall be a completely-defined object 1966 // type. Note that Functions are not objects, and that (in C99 parlance) 1967 // incomplete types are not object types. 1968 if (ResultType->isFunctionType()) { 1969 Diag(BaseExpr->getLocStart(), diag::err_subscript_function_type) 1970 << ResultType << BaseExpr->getSourceRange(); 1971 return ExprError(); 1972 } 1973 1974 if (!ResultType->isDependentType() && 1975 RequireCompleteType(LLoc, ResultType, 1976 PDiag(diag::err_subscript_incomplete_type) 1977 << BaseExpr->getSourceRange())) 1978 return ExprError(); 1979 1980 // Diagnose bad cases where we step over interface counts. 1981 if (ResultType->isObjCInterfaceType() && LangOpts.ObjCNonFragileABI) { 1982 Diag(LLoc, diag::err_subscript_nonfragile_interface) 1983 << ResultType << BaseExpr->getSourceRange(); 1984 return ExprError(); 1985 } 1986 1987 Base.release(); 1988 Idx.release(); 1989 return Owned(new (Context) ArraySubscriptExpr(LHSExp, RHSExp, 1990 ResultType, RLoc)); 1991} 1992 1993QualType Sema:: 1994CheckExtVectorComponent(QualType baseType, SourceLocation OpLoc, 1995 const IdentifierInfo *CompName, 1996 SourceLocation CompLoc) { 1997 // FIXME: Share logic with ExtVectorElementExpr::containsDuplicateElements, 1998 // see FIXME there. 1999 // 2000 // FIXME: This logic can be greatly simplified by splitting it along 2001 // halving/not halving and reworking the component checking. 2002 const ExtVectorType *vecType = baseType->getAs<ExtVectorType>(); 2003 2004 // The vector accessor can't exceed the number of elements. 2005 const char *compStr = CompName->getNameStart(); 2006 2007 // This flag determines whether or not the component is one of the four 2008 // special names that indicate a subset of exactly half the elements are 2009 // to be selected. 2010 bool HalvingSwizzle = false; 2011 2012 // This flag determines whether or not CompName has an 's' char prefix, 2013 // indicating that it is a string of hex values to be used as vector indices. 2014 bool HexSwizzle = *compStr == 's' || *compStr == 'S'; 2015 2016 // Check that we've found one of the special components, or that the component 2017 // names must come from the same set. 2018 if (!strcmp(compStr, "hi") || !strcmp(compStr, "lo") || 2019 !strcmp(compStr, "even") || !strcmp(compStr, "odd")) { 2020 HalvingSwizzle = true; 2021 } else if (vecType->getPointAccessorIdx(*compStr) != -1) { 2022 do 2023 compStr++; 2024 while (*compStr && vecType->getPointAccessorIdx(*compStr) != -1); 2025 } else if (HexSwizzle || vecType->getNumericAccessorIdx(*compStr) != -1) { 2026 do 2027 compStr++; 2028 while (*compStr && vecType->getNumericAccessorIdx(*compStr) != -1); 2029 } 2030 2031 if (!HalvingSwizzle && *compStr) { 2032 // We didn't get to the end of the string. This means the component names 2033 // didn't come from the same set *or* we encountered an illegal name. 2034 Diag(OpLoc, diag::err_ext_vector_component_name_illegal) 2035 << std::string(compStr,compStr+1) << SourceRange(CompLoc); 2036 return QualType(); 2037 } 2038 2039 // Ensure no component accessor exceeds the width of the vector type it 2040 // operates on. 2041 if (!HalvingSwizzle) { 2042 compStr = CompName->getNameStart(); 2043 2044 if (HexSwizzle) 2045 compStr++; 2046 2047 while (*compStr) { 2048 if (!vecType->isAccessorWithinNumElements(*compStr++)) { 2049 Diag(OpLoc, diag::err_ext_vector_component_exceeds_length) 2050 << baseType << SourceRange(CompLoc); 2051 return QualType(); 2052 } 2053 } 2054 } 2055 2056 // If this is a halving swizzle, verify that the base type has an even 2057 // number of elements. 2058 if (HalvingSwizzle && (vecType->getNumElements() & 1U)) { 2059 Diag(OpLoc, diag::err_ext_vector_component_requires_even) 2060 << baseType << SourceRange(CompLoc); 2061 return QualType(); 2062 } 2063 2064 // The component accessor looks fine - now we need to compute the actual type. 2065 // The vector type is implied by the component accessor. For example, 2066 // vec4.b is a float, vec4.xy is a vec2, vec4.rgb is a vec3, etc. 2067 // vec4.s0 is a float, vec4.s23 is a vec3, etc. 2068 // vec4.hi, vec4.lo, vec4.e, and vec4.o all return vec2. 2069 unsigned CompSize = HalvingSwizzle ? vecType->getNumElements() / 2 2070 : CompName->getLength(); 2071 if (HexSwizzle) 2072 CompSize--; 2073 2074 if (CompSize == 1) 2075 return vecType->getElementType(); 2076 2077 QualType VT = Context.getExtVectorType(vecType->getElementType(), CompSize); 2078 // Now look up the TypeDefDecl from the vector type. Without this, 2079 // diagostics look bad. We want extended vector types to appear built-in. 2080 for (unsigned i = 0, E = ExtVectorDecls.size(); i != E; ++i) { 2081 if (ExtVectorDecls[i]->getUnderlyingType() == VT) 2082 return Context.getTypedefType(ExtVectorDecls[i]); 2083 } 2084 return VT; // should never get here (a typedef type should always be found). 2085} 2086 2087static Decl *FindGetterNameDeclFromProtocolList(const ObjCProtocolDecl*PDecl, 2088 IdentifierInfo *Member, 2089 const Selector &Sel, 2090 ASTContext &Context) { 2091 2092 if (ObjCPropertyDecl *PD = PDecl->FindPropertyDeclaration(Member)) 2093 return PD; 2094 if (ObjCMethodDecl *OMD = PDecl->getInstanceMethod(Sel)) 2095 return OMD; 2096 2097 for (ObjCProtocolDecl::protocol_iterator I = PDecl->protocol_begin(), 2098 E = PDecl->protocol_end(); I != E; ++I) { 2099 if (Decl *D = FindGetterNameDeclFromProtocolList(*I, Member, Sel, 2100 Context)) 2101 return D; 2102 } 2103 return 0; 2104} 2105 2106static Decl *FindGetterNameDecl(const ObjCObjectPointerType *QIdTy, 2107 IdentifierInfo *Member, 2108 const Selector &Sel, 2109 ASTContext &Context) { 2110 // Check protocols on qualified interfaces. 2111 Decl *GDecl = 0; 2112 for (ObjCObjectPointerType::qual_iterator I = QIdTy->qual_begin(), 2113 E = QIdTy->qual_end(); I != E; ++I) { 2114 if (ObjCPropertyDecl *PD = (*I)->FindPropertyDeclaration(Member)) { 2115 GDecl = PD; 2116 break; 2117 } 2118 // Also must look for a getter name which uses property syntax. 2119 if (ObjCMethodDecl *OMD = (*I)->getInstanceMethod(Sel)) { 2120 GDecl = OMD; 2121 break; 2122 } 2123 } 2124 if (!GDecl) { 2125 for (ObjCObjectPointerType::qual_iterator I = QIdTy->qual_begin(), 2126 E = QIdTy->qual_end(); I != E; ++I) { 2127 // Search in the protocol-qualifier list of current protocol. 2128 GDecl = FindGetterNameDeclFromProtocolList(*I, Member, Sel, Context); 2129 if (GDecl) 2130 return GDecl; 2131 } 2132 } 2133 return GDecl; 2134} 2135 2136Sema::OwningExprResult 2137Sema::ActOnDependentMemberExpr(ExprArg Base, QualType BaseType, 2138 bool IsArrow, SourceLocation OpLoc, 2139 const CXXScopeSpec &SS, 2140 NamedDecl *FirstQualifierInScope, 2141 DeclarationName Name, SourceLocation NameLoc, 2142 const TemplateArgumentListInfo *TemplateArgs) { 2143 Expr *BaseExpr = Base.takeAs<Expr>(); 2144 2145 // Even in dependent contexts, try to diagnose base expressions with 2146 // obviously wrong types, e.g.: 2147 // 2148 // T* t; 2149 // t.f; 2150 // 2151 // In Obj-C++, however, the above expression is valid, since it could be 2152 // accessing the 'f' property if T is an Obj-C interface. The extra check 2153 // allows this, while still reporting an error if T is a struct pointer. 2154 if (!IsArrow) { 2155 const PointerType *PT = BaseType->getAs<PointerType>(); 2156 if (PT && (!getLangOptions().ObjC1 || 2157 PT->getPointeeType()->isRecordType())) { 2158 assert(BaseExpr && "cannot happen with implicit member accesses"); 2159 Diag(NameLoc, diag::err_typecheck_member_reference_struct_union) 2160 << BaseType << BaseExpr->getSourceRange(); 2161 return ExprError(); 2162 } 2163 } 2164 2165 assert(BaseType->isDependentType()); 2166 2167 // Get the type being accessed in BaseType. If this is an arrow, the BaseExpr 2168 // must have pointer type, and the accessed type is the pointee. 2169 return Owned(CXXDependentScopeMemberExpr::Create(Context, BaseExpr, BaseType, 2170 IsArrow, OpLoc, 2171 static_cast<NestedNameSpecifier*>(SS.getScopeRep()), 2172 SS.getRange(), 2173 FirstQualifierInScope, 2174 Name, NameLoc, 2175 TemplateArgs)); 2176} 2177 2178/// We know that the given qualified member reference points only to 2179/// declarations which do not belong to the static type of the base 2180/// expression. Diagnose the problem. 2181static void DiagnoseQualifiedMemberReference(Sema &SemaRef, 2182 Expr *BaseExpr, 2183 QualType BaseType, 2184 const CXXScopeSpec &SS, 2185 const LookupResult &R) { 2186 // If this is an implicit member access, use a different set of 2187 // diagnostics. 2188 if (!BaseExpr) 2189 return DiagnoseInstanceReference(SemaRef, SS, R); 2190 2191 // FIXME: this is an exceedingly lame diagnostic for some of the more 2192 // complicated cases here. 2193 DeclContext *DC = R.getRepresentativeDecl()->getDeclContext(); 2194 SemaRef.Diag(R.getNameLoc(), diag::err_not_direct_base_or_virtual) 2195 << SS.getRange() << DC << BaseType; 2196} 2197 2198// Check whether the declarations we found through a nested-name 2199// specifier in a member expression are actually members of the base 2200// type. The restriction here is: 2201// 2202// C++ [expr.ref]p2: 2203// ... In these cases, the id-expression shall name a 2204// member of the class or of one of its base classes. 2205// 2206// So it's perfectly legitimate for the nested-name specifier to name 2207// an unrelated class, and for us to find an overload set including 2208// decls from classes which are not superclasses, as long as the decl 2209// we actually pick through overload resolution is from a superclass. 2210bool Sema::CheckQualifiedMemberReference(Expr *BaseExpr, 2211 QualType BaseType, 2212 const CXXScopeSpec &SS, 2213 const LookupResult &R) { 2214 const RecordType *BaseRT = BaseType->getAs<RecordType>(); 2215 if (!BaseRT) { 2216 // We can't check this yet because the base type is still 2217 // dependent. 2218 assert(BaseType->isDependentType()); 2219 return false; 2220 } 2221 CXXRecordDecl *BaseRecord = cast<CXXRecordDecl>(BaseRT->getDecl()); 2222 2223 for (LookupResult::iterator I = R.begin(), E = R.end(); I != E; ++I) { 2224 // If this is an implicit member reference and we find a 2225 // non-instance member, it's not an error. 2226 if (!BaseExpr && !IsInstanceMember((*I)->getUnderlyingDecl())) 2227 return false; 2228 2229 // Note that we use the DC of the decl, not the underlying decl. 2230 CXXRecordDecl *RecordD = cast<CXXRecordDecl>((*I)->getDeclContext()); 2231 while (RecordD->isAnonymousStructOrUnion()) 2232 RecordD = cast<CXXRecordDecl>(RecordD->getParent()); 2233 2234 llvm::SmallPtrSet<CXXRecordDecl*,4> MemberRecord; 2235 MemberRecord.insert(RecordD->getCanonicalDecl()); 2236 2237 if (!IsProvablyNotDerivedFrom(*this, BaseRecord, MemberRecord)) 2238 return false; 2239 } 2240 2241 DiagnoseQualifiedMemberReference(*this, BaseExpr, BaseType, SS, R); 2242 return true; 2243} 2244 2245static bool 2246LookupMemberExprInRecord(Sema &SemaRef, LookupResult &R, 2247 SourceRange BaseRange, const RecordType *RTy, 2248 SourceLocation OpLoc, const CXXScopeSpec &SS) { 2249 RecordDecl *RDecl = RTy->getDecl(); 2250 if (SemaRef.RequireCompleteType(OpLoc, QualType(RTy, 0), 2251 PDiag(diag::err_typecheck_incomplete_tag) 2252 << BaseRange)) 2253 return true; 2254 2255 DeclContext *DC = RDecl; 2256 if (SS.isSet()) { 2257 // If the member name was a qualified-id, look into the 2258 // nested-name-specifier. 2259 DC = SemaRef.computeDeclContext(SS, false); 2260 2261 if (SemaRef.RequireCompleteDeclContext(SS)) { 2262 SemaRef.Diag(SS.getRange().getEnd(), diag::err_typecheck_incomplete_tag) 2263 << SS.getRange() << DC; 2264 return true; 2265 } 2266 2267 assert(DC && "Cannot handle non-computable dependent contexts in lookup"); 2268 2269 if (!isa<TypeDecl>(DC)) { 2270 SemaRef.Diag(R.getNameLoc(), diag::err_qualified_member_nonclass) 2271 << DC << SS.getRange(); 2272 return true; 2273 } 2274 } 2275 2276 // The record definition is complete, now look up the member. 2277 SemaRef.LookupQualifiedName(R, DC); 2278 2279 return false; 2280} 2281 2282Sema::OwningExprResult 2283Sema::BuildMemberReferenceExpr(ExprArg BaseArg, QualType BaseType, 2284 SourceLocation OpLoc, bool IsArrow, 2285 const CXXScopeSpec &SS, 2286 NamedDecl *FirstQualifierInScope, 2287 DeclarationName Name, SourceLocation NameLoc, 2288 const TemplateArgumentListInfo *TemplateArgs) { 2289 Expr *Base = BaseArg.takeAs<Expr>(); 2290 2291 if (BaseType->isDependentType() || 2292 (SS.isSet() && isDependentScopeSpecifier(SS))) 2293 return ActOnDependentMemberExpr(ExprArg(*this, Base), BaseType, 2294 IsArrow, OpLoc, 2295 SS, FirstQualifierInScope, 2296 Name, NameLoc, 2297 TemplateArgs); 2298 2299 LookupResult R(*this, Name, NameLoc, LookupMemberName); 2300 2301 // Implicit member accesses. 2302 if (!Base) { 2303 QualType RecordTy = BaseType; 2304 if (IsArrow) RecordTy = RecordTy->getAs<PointerType>()->getPointeeType(); 2305 if (LookupMemberExprInRecord(*this, R, SourceRange(), 2306 RecordTy->getAs<RecordType>(), 2307 OpLoc, SS)) 2308 return ExprError(); 2309 2310 // Explicit member accesses. 2311 } else { 2312 OwningExprResult Result = 2313 LookupMemberExpr(R, Base, IsArrow, OpLoc, 2314 SS, FirstQualifierInScope, 2315 /*ObjCImpDecl*/ DeclPtrTy()); 2316 2317 if (Result.isInvalid()) { 2318 Owned(Base); 2319 return ExprError(); 2320 } 2321 2322 if (Result.get()) 2323 return move(Result); 2324 } 2325 2326 return BuildMemberReferenceExpr(ExprArg(*this, Base), BaseType, 2327 OpLoc, IsArrow, SS, R, TemplateArgs); 2328} 2329 2330Sema::OwningExprResult 2331Sema::BuildMemberReferenceExpr(ExprArg Base, QualType BaseExprType, 2332 SourceLocation OpLoc, bool IsArrow, 2333 const CXXScopeSpec &SS, 2334 LookupResult &R, 2335 const TemplateArgumentListInfo *TemplateArgs) { 2336 Expr *BaseExpr = Base.takeAs<Expr>(); 2337 QualType BaseType = BaseExprType; 2338 if (IsArrow) { 2339 assert(BaseType->isPointerType()); 2340 BaseType = BaseType->getAs<PointerType>()->getPointeeType(); 2341 } 2342 2343 NestedNameSpecifier *Qualifier = 2344 static_cast<NestedNameSpecifier*>(SS.getScopeRep()); 2345 DeclarationName MemberName = R.getLookupName(); 2346 SourceLocation MemberLoc = R.getNameLoc(); 2347 2348 if (R.isAmbiguous()) 2349 return ExprError(); 2350 2351 if (R.empty()) { 2352 // Rederive where we looked up. 2353 DeclContext *DC = (SS.isSet() 2354 ? computeDeclContext(SS, false) 2355 : BaseType->getAs<RecordType>()->getDecl()); 2356 2357 Diag(R.getNameLoc(), diag::err_no_member) 2358 << MemberName << DC 2359 << (BaseExpr ? BaseExpr->getSourceRange() : SourceRange()); 2360 return ExprError(); 2361 } 2362 2363 // Diagnose qualified lookups that find only declarations from a 2364 // non-base type. Note that it's okay for lookup to find 2365 // declarations from a non-base type as long as those aren't the 2366 // ones picked by overload resolution. 2367 if (SS.isSet() && CheckQualifiedMemberReference(BaseExpr, BaseType, SS, R)) 2368 return ExprError(); 2369 2370 // Construct an unresolved result if we in fact got an unresolved 2371 // result. 2372 if (R.isOverloadedResult() || R.isUnresolvableResult()) { 2373 bool Dependent = 2374 R.isUnresolvableResult() || 2375 UnresolvedLookupExpr::ComputeDependence(R.begin(), R.end(), TemplateArgs); 2376 2377 UnresolvedMemberExpr *MemExpr 2378 = UnresolvedMemberExpr::Create(Context, Dependent, 2379 R.isUnresolvableResult(), 2380 BaseExpr, BaseExprType, 2381 IsArrow, OpLoc, 2382 Qualifier, SS.getRange(), 2383 MemberName, MemberLoc, 2384 TemplateArgs); 2385 for (LookupResult::iterator I = R.begin(), E = R.end(); I != E; ++I) 2386 MemExpr->addDecl(*I); 2387 2388 return Owned(MemExpr); 2389 } 2390 2391 assert(R.isSingleResult()); 2392 NamedDecl *MemberDecl = R.getFoundDecl(); 2393 2394 // FIXME: diagnose the presence of template arguments now. 2395 2396 // If the decl being referenced had an error, return an error for this 2397 // sub-expr without emitting another error, in order to avoid cascading 2398 // error cases. 2399 if (MemberDecl->isInvalidDecl()) 2400 return ExprError(); 2401 2402 // Handle the implicit-member-access case. 2403 if (!BaseExpr) { 2404 // If this is not an instance member, convert to a non-member access. 2405 if (!IsInstanceMember(MemberDecl)) 2406 return BuildDeclarationNameExpr(SS, R.getNameLoc(), MemberDecl); 2407 2408 BaseExpr = new (Context) CXXThisExpr(SourceLocation(), BaseExprType); 2409 } 2410 2411 bool ShouldCheckUse = true; 2412 if (CXXMethodDecl *MD = dyn_cast<CXXMethodDecl>(MemberDecl)) { 2413 // Don't diagnose the use of a virtual member function unless it's 2414 // explicitly qualified. 2415 if (MD->isVirtual() && !SS.isSet()) 2416 ShouldCheckUse = false; 2417 } 2418 2419 // Check the use of this member. 2420 if (ShouldCheckUse && DiagnoseUseOfDecl(MemberDecl, MemberLoc)) { 2421 Owned(BaseExpr); 2422 return ExprError(); 2423 } 2424 2425 if (FieldDecl *FD = dyn_cast<FieldDecl>(MemberDecl)) { 2426 // We may have found a field within an anonymous union or struct 2427 // (C++ [class.union]). 2428 if (cast<RecordDecl>(FD->getDeclContext())->isAnonymousStructOrUnion() && 2429 !BaseType->getAs<RecordType>()->getDecl()->isAnonymousStructOrUnion()) 2430 return BuildAnonymousStructUnionMemberReference(MemberLoc, FD, 2431 BaseExpr, OpLoc); 2432 2433 // Figure out the type of the member; see C99 6.5.2.3p3, C++ [expr.ref] 2434 QualType MemberType = FD->getType(); 2435 if (const ReferenceType *Ref = MemberType->getAs<ReferenceType>()) 2436 MemberType = Ref->getPointeeType(); 2437 else { 2438 Qualifiers BaseQuals = BaseType.getQualifiers(); 2439 BaseQuals.removeObjCGCAttr(); 2440 if (FD->isMutable()) BaseQuals.removeConst(); 2441 2442 Qualifiers MemberQuals 2443 = Context.getCanonicalType(MemberType).getQualifiers(); 2444 2445 Qualifiers Combined = BaseQuals + MemberQuals; 2446 if (Combined != MemberQuals) 2447 MemberType = Context.getQualifiedType(MemberType, Combined); 2448 } 2449 2450 MarkDeclarationReferenced(MemberLoc, FD); 2451 if (PerformObjectMemberConversion(BaseExpr, FD)) 2452 return ExprError(); 2453 return Owned(BuildMemberExpr(Context, BaseExpr, IsArrow, SS, 2454 FD, MemberLoc, MemberType)); 2455 } 2456 2457 if (VarDecl *Var = dyn_cast<VarDecl>(MemberDecl)) { 2458 MarkDeclarationReferenced(MemberLoc, Var); 2459 return Owned(BuildMemberExpr(Context, BaseExpr, IsArrow, SS, 2460 Var, MemberLoc, 2461 Var->getType().getNonReferenceType())); 2462 } 2463 2464 if (FunctionDecl *MemberFn = dyn_cast<FunctionDecl>(MemberDecl)) { 2465 MarkDeclarationReferenced(MemberLoc, MemberDecl); 2466 return Owned(BuildMemberExpr(Context, BaseExpr, IsArrow, SS, 2467 MemberFn, MemberLoc, 2468 MemberFn->getType())); 2469 } 2470 2471 if (EnumConstantDecl *Enum = dyn_cast<EnumConstantDecl>(MemberDecl)) { 2472 MarkDeclarationReferenced(MemberLoc, MemberDecl); 2473 return Owned(BuildMemberExpr(Context, BaseExpr, IsArrow, SS, 2474 Enum, MemberLoc, Enum->getType())); 2475 } 2476 2477 Owned(BaseExpr); 2478 2479 if (isa<TypeDecl>(MemberDecl)) 2480 return ExprError(Diag(MemberLoc,diag::err_typecheck_member_reference_type) 2481 << MemberName << int(IsArrow)); 2482 2483 // We found a declaration kind that we didn't expect. This is a 2484 // generic error message that tells the user that she can't refer 2485 // to this member with '.' or '->'. 2486 return ExprError(Diag(MemberLoc, 2487 diag::err_typecheck_member_reference_unknown) 2488 << MemberName << int(IsArrow)); 2489} 2490 2491/// Look up the given member of the given non-type-dependent 2492/// expression. This can return in one of two ways: 2493/// * If it returns a sentinel null-but-valid result, the caller will 2494/// assume that lookup was performed and the results written into 2495/// the provided structure. It will take over from there. 2496/// * Otherwise, the returned expression will be produced in place of 2497/// an ordinary member expression. 2498/// 2499/// The ObjCImpDecl bit is a gross hack that will need to be properly 2500/// fixed for ObjC++. 2501Sema::OwningExprResult 2502Sema::LookupMemberExpr(LookupResult &R, Expr *&BaseExpr, 2503 bool &IsArrow, SourceLocation OpLoc, 2504 const CXXScopeSpec &SS, 2505 NamedDecl *FirstQualifierInScope, 2506 DeclPtrTy ObjCImpDecl) { 2507 assert(BaseExpr && "no base expression"); 2508 2509 // Perform default conversions. 2510 DefaultFunctionArrayConversion(BaseExpr); 2511 2512 QualType BaseType = BaseExpr->getType(); 2513 assert(!BaseType->isDependentType()); 2514 2515 DeclarationName MemberName = R.getLookupName(); 2516 SourceLocation MemberLoc = R.getNameLoc(); 2517 2518 // If the user is trying to apply -> or . to a function pointer 2519 // type, it's probably because they forgot parentheses to call that 2520 // function. Suggest the addition of those parentheses, build the 2521 // call, and continue on. 2522 if (const PointerType *Ptr = BaseType->getAs<PointerType>()) { 2523 if (const FunctionProtoType *Fun 2524 = Ptr->getPointeeType()->getAs<FunctionProtoType>()) { 2525 QualType ResultTy = Fun->getResultType(); 2526 if (Fun->getNumArgs() == 0 && 2527 ((!IsArrow && ResultTy->isRecordType()) || 2528 (IsArrow && ResultTy->isPointerType() && 2529 ResultTy->getAs<PointerType>()->getPointeeType() 2530 ->isRecordType()))) { 2531 SourceLocation Loc = PP.getLocForEndOfToken(BaseExpr->getLocEnd()); 2532 Diag(Loc, diag::err_member_reference_needs_call) 2533 << QualType(Fun, 0) 2534 << CodeModificationHint::CreateInsertion(Loc, "()"); 2535 2536 OwningExprResult NewBase 2537 = ActOnCallExpr(0, ExprArg(*this, BaseExpr), Loc, 2538 MultiExprArg(*this, 0, 0), 0, Loc); 2539 if (NewBase.isInvalid()) 2540 return ExprError(); 2541 2542 BaseExpr = NewBase.takeAs<Expr>(); 2543 DefaultFunctionArrayConversion(BaseExpr); 2544 BaseType = BaseExpr->getType(); 2545 } 2546 } 2547 } 2548 2549 // If this is an Objective-C pseudo-builtin and a definition is provided then 2550 // use that. 2551 if (BaseType->isObjCIdType()) { 2552 if (IsArrow) { 2553 // Handle the following exceptional case PObj->isa. 2554 if (const ObjCObjectPointerType *OPT = 2555 BaseType->getAs<ObjCObjectPointerType>()) { 2556 if (OPT->getPointeeType()->isSpecificBuiltinType(BuiltinType::ObjCId) && 2557 MemberName.getAsIdentifierInfo()->isStr("isa")) 2558 return Owned(new (Context) ObjCIsaExpr(BaseExpr, true, MemberLoc, 2559 Context.getObjCClassType())); 2560 } 2561 } 2562 // We have an 'id' type. Rather than fall through, we check if this 2563 // is a reference to 'isa'. 2564 if (BaseType != Context.ObjCIdRedefinitionType) { 2565 BaseType = Context.ObjCIdRedefinitionType; 2566 ImpCastExprToType(BaseExpr, BaseType, CastExpr::CK_BitCast); 2567 } 2568 } 2569 2570 // If this is an Objective-C pseudo-builtin and a definition is provided then 2571 // use that. 2572 if (Context.isObjCSelType(BaseType)) { 2573 // We have an 'SEL' type. Rather than fall through, we check if this 2574 // is a reference to 'sel_id'. 2575 if (BaseType != Context.ObjCSelRedefinitionType) { 2576 BaseType = Context.ObjCSelRedefinitionType; 2577 ImpCastExprToType(BaseExpr, BaseType, CastExpr::CK_BitCast); 2578 } 2579 } 2580 2581 assert(!BaseType.isNull() && "no type for member expression"); 2582 2583 // Handle properties on ObjC 'Class' types. 2584 if (!IsArrow && BaseType->isObjCClassType()) { 2585 // Also must look for a getter name which uses property syntax. 2586 IdentifierInfo *Member = MemberName.getAsIdentifierInfo(); 2587 Selector Sel = PP.getSelectorTable().getNullarySelector(Member); 2588 if (ObjCMethodDecl *MD = getCurMethodDecl()) { 2589 ObjCInterfaceDecl *IFace = MD->getClassInterface(); 2590 ObjCMethodDecl *Getter; 2591 // FIXME: need to also look locally in the implementation. 2592 if ((Getter = IFace->lookupClassMethod(Sel))) { 2593 // Check the use of this method. 2594 if (DiagnoseUseOfDecl(Getter, MemberLoc)) 2595 return ExprError(); 2596 } 2597 // If we found a getter then this may be a valid dot-reference, we 2598 // will look for the matching setter, in case it is needed. 2599 Selector SetterSel = 2600 SelectorTable::constructSetterName(PP.getIdentifierTable(), 2601 PP.getSelectorTable(), Member); 2602 ObjCMethodDecl *Setter = IFace->lookupClassMethod(SetterSel); 2603 if (!Setter) { 2604 // If this reference is in an @implementation, also check for 'private' 2605 // methods. 2606 Setter = IFace->lookupPrivateInstanceMethod(SetterSel); 2607 } 2608 // Look through local category implementations associated with the class. 2609 if (!Setter) 2610 Setter = IFace->getCategoryClassMethod(SetterSel); 2611 2612 if (Setter && DiagnoseUseOfDecl(Setter, MemberLoc)) 2613 return ExprError(); 2614 2615 if (Getter || Setter) { 2616 QualType PType; 2617 2618 if (Getter) 2619 PType = Getter->getResultType(); 2620 else 2621 // Get the expression type from Setter's incoming parameter. 2622 PType = (*(Setter->param_end() -1))->getType(); 2623 // FIXME: we must check that the setter has property type. 2624 return Owned(new (Context) ObjCImplicitSetterGetterRefExpr(Getter, 2625 PType, 2626 Setter, MemberLoc, BaseExpr)); 2627 } 2628 return ExprError(Diag(MemberLoc, diag::err_property_not_found) 2629 << MemberName << BaseType); 2630 } 2631 } 2632 2633 if (BaseType->isObjCClassType() && 2634 BaseType != Context.ObjCClassRedefinitionType) { 2635 BaseType = Context.ObjCClassRedefinitionType; 2636 ImpCastExprToType(BaseExpr, BaseType, CastExpr::CK_BitCast); 2637 } 2638 2639 if (IsArrow) { 2640 if (const PointerType *PT = BaseType->getAs<PointerType>()) 2641 BaseType = PT->getPointeeType(); 2642 else if (BaseType->isObjCObjectPointerType()) 2643 ; 2644 else if (BaseType->isRecordType()) { 2645 // Recover from arrow accesses to records, e.g.: 2646 // struct MyRecord foo; 2647 // foo->bar 2648 // This is actually well-formed in C++ if MyRecord has an 2649 // overloaded operator->, but that should have been dealt with 2650 // by now. 2651 Diag(OpLoc, diag::err_typecheck_member_reference_suggestion) 2652 << BaseType << int(IsArrow) << BaseExpr->getSourceRange() 2653 << CodeModificationHint::CreateReplacement(OpLoc, "."); 2654 IsArrow = false; 2655 } else { 2656 Diag(MemberLoc, diag::err_typecheck_member_reference_arrow) 2657 << BaseType << BaseExpr->getSourceRange(); 2658 return ExprError(); 2659 } 2660 } else { 2661 // Recover from dot accesses to pointers, e.g.: 2662 // type *foo; 2663 // foo.bar 2664 // This is actually well-formed in two cases: 2665 // - 'type' is an Objective C type 2666 // - 'bar' is a pseudo-destructor name which happens to refer to 2667 // the appropriate pointer type 2668 if (MemberName.getNameKind() != DeclarationName::CXXDestructorName) { 2669 const PointerType *PT = BaseType->getAs<PointerType>(); 2670 if (PT && PT->getPointeeType()->isRecordType()) { 2671 Diag(OpLoc, diag::err_typecheck_member_reference_suggestion) 2672 << BaseType << int(IsArrow) << BaseExpr->getSourceRange() 2673 << CodeModificationHint::CreateReplacement(OpLoc, "->"); 2674 BaseType = PT->getPointeeType(); 2675 IsArrow = true; 2676 } 2677 } 2678 } 2679 2680 // Handle field access to simple records. This also handles access 2681 // to fields of the ObjC 'id' struct. 2682 if (const RecordType *RTy = BaseType->getAs<RecordType>()) { 2683 if (LookupMemberExprInRecord(*this, R, BaseExpr->getSourceRange(), 2684 RTy, OpLoc, SS)) 2685 return ExprError(); 2686 return Owned((Expr*) 0); 2687 } 2688 2689 // Handle pseudo-destructors (C++ [expr.pseudo]). Since anything referring 2690 // into a record type was handled above, any destructor we see here is a 2691 // pseudo-destructor. 2692 if (MemberName.getNameKind() == DeclarationName::CXXDestructorName) { 2693 // C++ [expr.pseudo]p2: 2694 // The left hand side of the dot operator shall be of scalar type. The 2695 // left hand side of the arrow operator shall be of pointer to scalar 2696 // type. 2697 if (!BaseType->isScalarType()) 2698 return Owned(Diag(OpLoc, diag::err_pseudo_dtor_base_not_scalar) 2699 << BaseType << BaseExpr->getSourceRange()); 2700 2701 // [...] The type designated by the pseudo-destructor-name shall be the 2702 // same as the object type. 2703 if (!MemberName.getCXXNameType()->isDependentType() && 2704 !Context.hasSameUnqualifiedType(BaseType, MemberName.getCXXNameType())) 2705 return Owned(Diag(OpLoc, diag::err_pseudo_dtor_type_mismatch) 2706 << BaseType << MemberName.getCXXNameType() 2707 << BaseExpr->getSourceRange() << SourceRange(MemberLoc)); 2708 2709 // [...] Furthermore, the two type-names in a pseudo-destructor-name of 2710 // the form 2711 // 2712 // ::[opt] nested-name-specifier[opt] type-name :: ̃ type-name 2713 // 2714 // shall designate the same scalar type. 2715 // 2716 // FIXME: DPG can't see any way to trigger this particular clause, so it 2717 // isn't checked here. 2718 2719 // FIXME: We've lost the precise spelling of the type by going through 2720 // DeclarationName. Can we do better? 2721 return Owned(new (Context) CXXPseudoDestructorExpr(Context, BaseExpr, 2722 IsArrow, OpLoc, 2723 (NestedNameSpecifier *) SS.getScopeRep(), 2724 SS.getRange(), 2725 MemberName.getCXXNameType(), 2726 MemberLoc)); 2727 } 2728 2729 // Handle access to Objective-C instance variables, such as "Obj->ivar" and 2730 // (*Obj).ivar. 2731 if ((IsArrow && BaseType->isObjCObjectPointerType()) || 2732 (!IsArrow && BaseType->isObjCInterfaceType())) { 2733 const ObjCObjectPointerType *OPT = BaseType->getAs<ObjCObjectPointerType>(); 2734 const ObjCInterfaceType *IFaceT = 2735 OPT ? OPT->getInterfaceType() : BaseType->getAs<ObjCInterfaceType>(); 2736 if (IFaceT) { 2737 IdentifierInfo *Member = MemberName.getAsIdentifierInfo(); 2738 2739 ObjCInterfaceDecl *IDecl = IFaceT->getDecl(); 2740 ObjCInterfaceDecl *ClassDeclared; 2741 ObjCIvarDecl *IV = IDecl->lookupInstanceVariable(Member, ClassDeclared); 2742 2743 if (IV) { 2744 // If the decl being referenced had an error, return an error for this 2745 // sub-expr without emitting another error, in order to avoid cascading 2746 // error cases. 2747 if (IV->isInvalidDecl()) 2748 return ExprError(); 2749 2750 // Check whether we can reference this field. 2751 if (DiagnoseUseOfDecl(IV, MemberLoc)) 2752 return ExprError(); 2753 if (IV->getAccessControl() != ObjCIvarDecl::Public && 2754 IV->getAccessControl() != ObjCIvarDecl::Package) { 2755 ObjCInterfaceDecl *ClassOfMethodDecl = 0; 2756 if (ObjCMethodDecl *MD = getCurMethodDecl()) 2757 ClassOfMethodDecl = MD->getClassInterface(); 2758 else if (ObjCImpDecl && getCurFunctionDecl()) { 2759 // Case of a c-function declared inside an objc implementation. 2760 // FIXME: For a c-style function nested inside an objc implementation 2761 // class, there is no implementation context available, so we pass 2762 // down the context as argument to this routine. Ideally, this context 2763 // need be passed down in the AST node and somehow calculated from the 2764 // AST for a function decl. 2765 Decl *ImplDecl = ObjCImpDecl.getAs<Decl>(); 2766 if (ObjCImplementationDecl *IMPD = 2767 dyn_cast<ObjCImplementationDecl>(ImplDecl)) 2768 ClassOfMethodDecl = IMPD->getClassInterface(); 2769 else if (ObjCCategoryImplDecl* CatImplClass = 2770 dyn_cast<ObjCCategoryImplDecl>(ImplDecl)) 2771 ClassOfMethodDecl = CatImplClass->getClassInterface(); 2772 } 2773 2774 if (IV->getAccessControl() == ObjCIvarDecl::Private) { 2775 if (ClassDeclared != IDecl || 2776 ClassOfMethodDecl != ClassDeclared) 2777 Diag(MemberLoc, diag::error_private_ivar_access) 2778 << IV->getDeclName(); 2779 } else if (!IDecl->isSuperClassOf(ClassOfMethodDecl)) 2780 // @protected 2781 Diag(MemberLoc, diag::error_protected_ivar_access) 2782 << IV->getDeclName(); 2783 } 2784 2785 return Owned(new (Context) ObjCIvarRefExpr(IV, IV->getType(), 2786 MemberLoc, BaseExpr, 2787 IsArrow)); 2788 } 2789 return ExprError(Diag(MemberLoc, diag::err_typecheck_member_reference_ivar) 2790 << IDecl->getDeclName() << MemberName 2791 << BaseExpr->getSourceRange()); 2792 } 2793 } 2794 // Handle properties on 'id' and qualified "id". 2795 if (!IsArrow && (BaseType->isObjCIdType() || 2796 BaseType->isObjCQualifiedIdType())) { 2797 const ObjCObjectPointerType *QIdTy = BaseType->getAs<ObjCObjectPointerType>(); 2798 IdentifierInfo *Member = MemberName.getAsIdentifierInfo(); 2799 2800 // Check protocols on qualified interfaces. 2801 Selector Sel = PP.getSelectorTable().getNullarySelector(Member); 2802 if (Decl *PMDecl = FindGetterNameDecl(QIdTy, Member, Sel, Context)) { 2803 if (ObjCPropertyDecl *PD = dyn_cast<ObjCPropertyDecl>(PMDecl)) { 2804 // Check the use of this declaration 2805 if (DiagnoseUseOfDecl(PD, MemberLoc)) 2806 return ExprError(); 2807 2808 return Owned(new (Context) ObjCPropertyRefExpr(PD, PD->getType(), 2809 MemberLoc, BaseExpr)); 2810 } 2811 if (ObjCMethodDecl *OMD = dyn_cast<ObjCMethodDecl>(PMDecl)) { 2812 // Check the use of this method. 2813 if (DiagnoseUseOfDecl(OMD, MemberLoc)) 2814 return ExprError(); 2815 2816 return Owned(new (Context) ObjCMessageExpr(BaseExpr, Sel, 2817 OMD->getResultType(), 2818 OMD, OpLoc, MemberLoc, 2819 NULL, 0)); 2820 } 2821 } 2822 2823 return ExprError(Diag(MemberLoc, diag::err_property_not_found) 2824 << MemberName << BaseType); 2825 } 2826 // Handle Objective-C property access, which is "Obj.property" where Obj is a 2827 // pointer to a (potentially qualified) interface type. 2828 const ObjCObjectPointerType *OPT; 2829 if (!IsArrow && (OPT = BaseType->getAsObjCInterfacePointerType())) { 2830 const ObjCInterfaceType *IFaceT = OPT->getInterfaceType(); 2831 ObjCInterfaceDecl *IFace = IFaceT->getDecl(); 2832 IdentifierInfo *Member = MemberName.getAsIdentifierInfo(); 2833 2834 // Search for a declared property first. 2835 if (ObjCPropertyDecl *PD = IFace->FindPropertyDeclaration(Member)) { 2836 // Check whether we can reference this property. 2837 if (DiagnoseUseOfDecl(PD, MemberLoc)) 2838 return ExprError(); 2839 QualType ResTy = PD->getType(); 2840 Selector Sel = PP.getSelectorTable().getNullarySelector(Member); 2841 ObjCMethodDecl *Getter = IFace->lookupInstanceMethod(Sel); 2842 if (DiagnosePropertyAccessorMismatch(PD, Getter, MemberLoc)) 2843 ResTy = Getter->getResultType(); 2844 return Owned(new (Context) ObjCPropertyRefExpr(PD, ResTy, 2845 MemberLoc, BaseExpr)); 2846 } 2847 // Check protocols on qualified interfaces. 2848 for (ObjCObjectPointerType::qual_iterator I = OPT->qual_begin(), 2849 E = OPT->qual_end(); I != E; ++I) 2850 if (ObjCPropertyDecl *PD = (*I)->FindPropertyDeclaration(Member)) { 2851 // Check whether we can reference this property. 2852 if (DiagnoseUseOfDecl(PD, MemberLoc)) 2853 return ExprError(); 2854 2855 return Owned(new (Context) ObjCPropertyRefExpr(PD, PD->getType(), 2856 MemberLoc, BaseExpr)); 2857 } 2858 // If that failed, look for an "implicit" property by seeing if the nullary 2859 // selector is implemented. 2860 2861 // FIXME: The logic for looking up nullary and unary selectors should be 2862 // shared with the code in ActOnInstanceMessage. 2863 2864 Selector Sel = PP.getSelectorTable().getNullarySelector(Member); 2865 ObjCMethodDecl *Getter = IFace->lookupInstanceMethod(Sel); 2866 2867 // If this reference is in an @implementation, check for 'private' methods. 2868 if (!Getter) 2869 Getter = IFace->lookupPrivateInstanceMethod(Sel); 2870 2871 // Look through local category implementations associated with the class. 2872 if (!Getter) 2873 Getter = IFace->getCategoryInstanceMethod(Sel); 2874 if (Getter) { 2875 // Check if we can reference this property. 2876 if (DiagnoseUseOfDecl(Getter, MemberLoc)) 2877 return ExprError(); 2878 } 2879 // If we found a getter then this may be a valid dot-reference, we 2880 // will look for the matching setter, in case it is needed. 2881 Selector SetterSel = 2882 SelectorTable::constructSetterName(PP.getIdentifierTable(), 2883 PP.getSelectorTable(), Member); 2884 ObjCMethodDecl *Setter = IFace->lookupInstanceMethod(SetterSel); 2885 if (!Setter) { 2886 // If this reference is in an @implementation, also check for 'private' 2887 // methods. 2888 Setter = IFace->lookupPrivateInstanceMethod(SetterSel); 2889 } 2890 // Look through local category implementations associated with the class. 2891 if (!Setter) 2892 Setter = IFace->getCategoryInstanceMethod(SetterSel); 2893 2894 if (Setter && DiagnoseUseOfDecl(Setter, MemberLoc)) 2895 return ExprError(); 2896 2897 if (Getter || Setter) { 2898 QualType PType; 2899 2900 if (Getter) 2901 PType = Getter->getResultType(); 2902 else 2903 // Get the expression type from Setter's incoming parameter. 2904 PType = (*(Setter->param_end() -1))->getType(); 2905 // FIXME: we must check that the setter has property type. 2906 return Owned(new (Context) ObjCImplicitSetterGetterRefExpr(Getter, PType, 2907 Setter, MemberLoc, BaseExpr)); 2908 } 2909 return ExprError(Diag(MemberLoc, diag::err_property_not_found) 2910 << MemberName << BaseType); 2911 } 2912 2913 // Handle the following exceptional case (*Obj).isa. 2914 if (!IsArrow && 2915 BaseType->isSpecificBuiltinType(BuiltinType::ObjCId) && 2916 MemberName.getAsIdentifierInfo()->isStr("isa")) 2917 return Owned(new (Context) ObjCIsaExpr(BaseExpr, false, MemberLoc, 2918 Context.getObjCClassType())); 2919 2920 // Handle 'field access' to vectors, such as 'V.xx'. 2921 if (BaseType->isExtVectorType()) { 2922 IdentifierInfo *Member = MemberName.getAsIdentifierInfo(); 2923 QualType ret = CheckExtVectorComponent(BaseType, OpLoc, Member, MemberLoc); 2924 if (ret.isNull()) 2925 return ExprError(); 2926 return Owned(new (Context) ExtVectorElementExpr(ret, BaseExpr, *Member, 2927 MemberLoc)); 2928 } 2929 2930 Diag(MemberLoc, diag::err_typecheck_member_reference_struct_union) 2931 << BaseType << BaseExpr->getSourceRange(); 2932 2933 return ExprError(); 2934} 2935 2936static Sema::OwningExprResult DiagnoseDtorReference(Sema &SemaRef, 2937 SourceLocation NameLoc, 2938 Sema::ExprArg MemExpr) { 2939 Expr *E = (Expr *) MemExpr.get(); 2940 SourceLocation ExpectedLParenLoc = SemaRef.PP.getLocForEndOfToken(NameLoc); 2941 SemaRef.Diag(E->getLocStart(), diag::err_dtor_expr_without_call) 2942 << isa<CXXPseudoDestructorExpr>(E) 2943 << CodeModificationHint::CreateInsertion(ExpectedLParenLoc, "()"); 2944 2945 return SemaRef.ActOnCallExpr(/*Scope*/ 0, 2946 move(MemExpr), 2947 /*LPLoc*/ ExpectedLParenLoc, 2948 Sema::MultiExprArg(SemaRef, 0, 0), 2949 /*CommaLocs*/ 0, 2950 /*RPLoc*/ ExpectedLParenLoc); 2951} 2952 2953/// The main callback when the parser finds something like 2954/// expression . [nested-name-specifier] identifier 2955/// expression -> [nested-name-specifier] identifier 2956/// where 'identifier' encompasses a fairly broad spectrum of 2957/// possibilities, including destructor and operator references. 2958/// 2959/// \param OpKind either tok::arrow or tok::period 2960/// \param HasTrailingLParen whether the next token is '(', which 2961/// is used to diagnose mis-uses of special members that can 2962/// only be called 2963/// \param ObjCImpDecl the current ObjC @implementation decl; 2964/// this is an ugly hack around the fact that ObjC @implementations 2965/// aren't properly put in the context chain 2966Sema::OwningExprResult Sema::ActOnMemberAccessExpr(Scope *S, ExprArg BaseArg, 2967 SourceLocation OpLoc, 2968 tok::TokenKind OpKind, 2969 const CXXScopeSpec &SS, 2970 UnqualifiedId &Id, 2971 DeclPtrTy ObjCImpDecl, 2972 bool HasTrailingLParen) { 2973 if (SS.isSet() && SS.isInvalid()) 2974 return ExprError(); 2975 2976 TemplateArgumentListInfo TemplateArgsBuffer; 2977 2978 // Decompose the name into its component parts. 2979 DeclarationName Name; 2980 SourceLocation NameLoc; 2981 const TemplateArgumentListInfo *TemplateArgs; 2982 DecomposeUnqualifiedId(*this, Id, TemplateArgsBuffer, 2983 Name, NameLoc, TemplateArgs); 2984 2985 bool IsArrow = (OpKind == tok::arrow); 2986 2987 NamedDecl *FirstQualifierInScope 2988 = (!SS.isSet() ? 0 : FindFirstQualifierInScope(S, 2989 static_cast<NestedNameSpecifier*>(SS.getScopeRep()))); 2990 2991 // This is a postfix expression, so get rid of ParenListExprs. 2992 BaseArg = MaybeConvertParenListExprToParenExpr(S, move(BaseArg)); 2993 2994 Expr *Base = BaseArg.takeAs<Expr>(); 2995 OwningExprResult Result(*this); 2996 if (Base->getType()->isDependentType()) { 2997 Result = ActOnDependentMemberExpr(ExprArg(*this, Base), Base->getType(), 2998 IsArrow, OpLoc, 2999 SS, FirstQualifierInScope, 3000 Name, NameLoc, 3001 TemplateArgs); 3002 } else { 3003 LookupResult R(*this, Name, NameLoc, LookupMemberName); 3004 if (TemplateArgs) { 3005 // Re-use the lookup done for the template name. 3006 DecomposeTemplateName(R, Id); 3007 } else { 3008 Result = LookupMemberExpr(R, Base, IsArrow, OpLoc, 3009 SS, FirstQualifierInScope, 3010 ObjCImpDecl); 3011 3012 if (Result.isInvalid()) { 3013 Owned(Base); 3014 return ExprError(); 3015 } 3016 3017 if (Result.get()) { 3018 // The only way a reference to a destructor can be used is to 3019 // immediately call it, which falls into this case. If the 3020 // next token is not a '(', produce a diagnostic and build the 3021 // call now. 3022 if (!HasTrailingLParen && 3023 Id.getKind() == UnqualifiedId::IK_DestructorName) 3024 return DiagnoseDtorReference(*this, NameLoc, move(Result)); 3025 3026 return move(Result); 3027 } 3028 } 3029 3030 Result = BuildMemberReferenceExpr(ExprArg(*this, Base), Base->getType(), 3031 OpLoc, IsArrow, SS, R, TemplateArgs); 3032 } 3033 3034 return move(Result); 3035} 3036 3037Sema::OwningExprResult Sema::BuildCXXDefaultArgExpr(SourceLocation CallLoc, 3038 FunctionDecl *FD, 3039 ParmVarDecl *Param) { 3040 if (Param->hasUnparsedDefaultArg()) { 3041 Diag (CallLoc, 3042 diag::err_use_of_default_argument_to_function_declared_later) << 3043 FD << cast<CXXRecordDecl>(FD->getDeclContext())->getDeclName(); 3044 Diag(UnparsedDefaultArgLocs[Param], 3045 diag::note_default_argument_declared_here); 3046 } else { 3047 if (Param->hasUninstantiatedDefaultArg()) { 3048 Expr *UninstExpr = Param->getUninstantiatedDefaultArg(); 3049 3050 // Instantiate the expression. 3051 MultiLevelTemplateArgumentList ArgList = getTemplateInstantiationArgs(FD); 3052 3053 InstantiatingTemplate Inst(*this, CallLoc, Param, 3054 ArgList.getInnermost().getFlatArgumentList(), 3055 ArgList.getInnermost().flat_size()); 3056 3057 OwningExprResult Result = SubstExpr(UninstExpr, ArgList); 3058 if (Result.isInvalid()) 3059 return ExprError(); 3060 3061 if (SetParamDefaultArgument(Param, move(Result), 3062 /*FIXME:EqualLoc*/ 3063 UninstExpr->getSourceRange().getBegin())) 3064 return ExprError(); 3065 } 3066 3067 Expr *DefaultExpr = Param->getDefaultArg(); 3068 3069 // If the default expression creates temporaries, we need to 3070 // push them to the current stack of expression temporaries so they'll 3071 // be properly destroyed. 3072 if (CXXExprWithTemporaries *E 3073 = dyn_cast_or_null<CXXExprWithTemporaries>(DefaultExpr)) { 3074 assert(!E->shouldDestroyTemporaries() && 3075 "Can't destroy temporaries in a default argument expr!"); 3076 for (unsigned I = 0, N = E->getNumTemporaries(); I != N; ++I) 3077 ExprTemporaries.push_back(E->getTemporary(I)); 3078 } 3079 } 3080 3081 // We already type-checked the argument, so we know it works. 3082 return Owned(CXXDefaultArgExpr::Create(Context, Param)); 3083} 3084 3085/// ConvertArgumentsForCall - Converts the arguments specified in 3086/// Args/NumArgs to the parameter types of the function FDecl with 3087/// function prototype Proto. Call is the call expression itself, and 3088/// Fn is the function expression. For a C++ member function, this 3089/// routine does not attempt to convert the object argument. Returns 3090/// true if the call is ill-formed. 3091bool 3092Sema::ConvertArgumentsForCall(CallExpr *Call, Expr *Fn, 3093 FunctionDecl *FDecl, 3094 const FunctionProtoType *Proto, 3095 Expr **Args, unsigned NumArgs, 3096 SourceLocation RParenLoc) { 3097 // C99 6.5.2.2p7 - the arguments are implicitly converted, as if by 3098 // assignment, to the types of the corresponding parameter, ... 3099 unsigned NumArgsInProto = Proto->getNumArgs(); 3100 bool Invalid = false; 3101 3102 // If too few arguments are available (and we don't have default 3103 // arguments for the remaining parameters), don't make the call. 3104 if (NumArgs < NumArgsInProto) { 3105 if (!FDecl || NumArgs < FDecl->getMinRequiredArguments()) 3106 return Diag(RParenLoc, diag::err_typecheck_call_too_few_args) 3107 << Fn->getType()->isBlockPointerType() << Fn->getSourceRange(); 3108 Call->setNumArgs(Context, NumArgsInProto); 3109 } 3110 3111 // If too many are passed and not variadic, error on the extras and drop 3112 // them. 3113 if (NumArgs > NumArgsInProto) { 3114 if (!Proto->isVariadic()) { 3115 Diag(Args[NumArgsInProto]->getLocStart(), 3116 diag::err_typecheck_call_too_many_args) 3117 << Fn->getType()->isBlockPointerType() << Fn->getSourceRange() 3118 << SourceRange(Args[NumArgsInProto]->getLocStart(), 3119 Args[NumArgs-1]->getLocEnd()); 3120 // This deletes the extra arguments. 3121 Call->setNumArgs(Context, NumArgsInProto); 3122 return true; 3123 } 3124 } 3125 llvm::SmallVector<Expr *, 8> AllArgs; 3126 VariadicCallType CallType = 3127 Proto->isVariadic() ? VariadicFunction : VariadicDoesNotApply; 3128 if (Fn->getType()->isBlockPointerType()) 3129 CallType = VariadicBlock; // Block 3130 else if (isa<MemberExpr>(Fn)) 3131 CallType = VariadicMethod; 3132 Invalid = GatherArgumentsForCall(Call->getSourceRange().getBegin(), FDecl, 3133 Proto, 0, Args, NumArgs, AllArgs, CallType); 3134 if (Invalid) 3135 return true; 3136 unsigned TotalNumArgs = AllArgs.size(); 3137 for (unsigned i = 0; i < TotalNumArgs; ++i) 3138 Call->setArg(i, AllArgs[i]); 3139 3140 return false; 3141} 3142 3143bool Sema::GatherArgumentsForCall(SourceLocation CallLoc, 3144 FunctionDecl *FDecl, 3145 const FunctionProtoType *Proto, 3146 unsigned FirstProtoArg, 3147 Expr **Args, unsigned NumArgs, 3148 llvm::SmallVector<Expr *, 8> &AllArgs, 3149 VariadicCallType CallType) { 3150 unsigned NumArgsInProto = Proto->getNumArgs(); 3151 unsigned NumArgsToCheck = NumArgs; 3152 bool Invalid = false; 3153 if (NumArgs != NumArgsInProto) 3154 // Use default arguments for missing arguments 3155 NumArgsToCheck = NumArgsInProto; 3156 unsigned ArgIx = 0; 3157 // Continue to check argument types (even if we have too few/many args). 3158 for (unsigned i = FirstProtoArg; i != NumArgsToCheck; i++) { 3159 QualType ProtoArgType = Proto->getArgType(i); 3160 3161 Expr *Arg; 3162 if (ArgIx < NumArgs) { 3163 Arg = Args[ArgIx++]; 3164 3165 if (RequireCompleteType(Arg->getSourceRange().getBegin(), 3166 ProtoArgType, 3167 PDiag(diag::err_call_incomplete_argument) 3168 << Arg->getSourceRange())) 3169 return true; 3170 3171 // Pass the argument. 3172 if (PerformCopyInitialization(Arg, ProtoArgType, "passing")) 3173 return true; 3174 3175 if (!ProtoArgType->isReferenceType()) 3176 Arg = MaybeBindToTemporary(Arg).takeAs<Expr>(); 3177 } else { 3178 ParmVarDecl *Param = FDecl->getParamDecl(i); 3179 3180 OwningExprResult ArgExpr = 3181 BuildCXXDefaultArgExpr(CallLoc, FDecl, Param); 3182 if (ArgExpr.isInvalid()) 3183 return true; 3184 3185 Arg = ArgExpr.takeAs<Expr>(); 3186 } 3187 AllArgs.push_back(Arg); 3188 } 3189 3190 // If this is a variadic call, handle args passed through "...". 3191 if (CallType != VariadicDoesNotApply) { 3192 // Promote the arguments (C99 6.5.2.2p7). 3193 for (unsigned i = ArgIx; i < NumArgs; i++) { 3194 Expr *Arg = Args[i]; 3195 Invalid |= DefaultVariadicArgumentPromotion(Arg, CallType); 3196 AllArgs.push_back(Arg); 3197 } 3198 } 3199 return Invalid; 3200} 3201 3202/// \brief "Deconstruct" the function argument of a call expression to find 3203/// the underlying declaration (if any), the name of the called function, 3204/// whether argument-dependent lookup is available, whether it has explicit 3205/// template arguments, etc. 3206void Sema::DeconstructCallFunction(Expr *FnExpr, 3207 llvm::SmallVectorImpl<NamedDecl*> &Fns, 3208 DeclarationName &Name, 3209 NestedNameSpecifier *&Qualifier, 3210 SourceRange &QualifierRange, 3211 bool &ArgumentDependentLookup, 3212 bool &Overloaded, 3213 bool &HasExplicitTemplateArguments, 3214 TemplateArgumentListInfo &ExplicitTemplateArgs) { 3215 // Set defaults for all of the output parameters. 3216 Name = DeclarationName(); 3217 Qualifier = 0; 3218 QualifierRange = SourceRange(); 3219 ArgumentDependentLookup = false; 3220 Overloaded = false; 3221 HasExplicitTemplateArguments = false; 3222 3223 // If we're directly calling a function, get the appropriate declaration. 3224 // Also, in C++, keep track of whether we should perform argument-dependent 3225 // lookup and whether there were any explicitly-specified template arguments. 3226 while (true) { 3227 if (ImplicitCastExpr *IcExpr = dyn_cast<ImplicitCastExpr>(FnExpr)) 3228 FnExpr = IcExpr->getSubExpr(); 3229 else if (ParenExpr *PExpr = dyn_cast<ParenExpr>(FnExpr)) { 3230 FnExpr = PExpr->getSubExpr(); 3231 } else if (isa<UnaryOperator>(FnExpr) && 3232 cast<UnaryOperator>(FnExpr)->getOpcode() 3233 == UnaryOperator::AddrOf) { 3234 FnExpr = cast<UnaryOperator>(FnExpr)->getSubExpr(); 3235 } else if (DeclRefExpr *DRExpr = dyn_cast<DeclRefExpr>(FnExpr)) { 3236 Fns.push_back(cast<NamedDecl>(DRExpr->getDecl())); 3237 ArgumentDependentLookup = false; 3238 if ((Qualifier = DRExpr->getQualifier())) 3239 QualifierRange = DRExpr->getQualifierRange(); 3240 break; 3241 } else if (UnresolvedLookupExpr *UnresLookup 3242 = dyn_cast<UnresolvedLookupExpr>(FnExpr)) { 3243 Name = UnresLookup->getName(); 3244 Fns.append(UnresLookup->decls_begin(), UnresLookup->decls_end()); 3245 ArgumentDependentLookup = UnresLookup->requiresADL(); 3246 Overloaded = UnresLookup->isOverloaded(); 3247 if ((Qualifier = UnresLookup->getQualifier())) 3248 QualifierRange = UnresLookup->getQualifierRange(); 3249 if (UnresLookup->hasExplicitTemplateArgs()) { 3250 HasExplicitTemplateArguments = true; 3251 UnresLookup->copyTemplateArgumentsInto(ExplicitTemplateArgs); 3252 } 3253 break; 3254 } else { 3255 break; 3256 } 3257 } 3258} 3259 3260/// ActOnCallExpr - Handle a call to Fn with the specified array of arguments. 3261/// This provides the location of the left/right parens and a list of comma 3262/// locations. 3263Action::OwningExprResult 3264Sema::ActOnCallExpr(Scope *S, ExprArg fn, SourceLocation LParenLoc, 3265 MultiExprArg args, 3266 SourceLocation *CommaLocs, SourceLocation RParenLoc) { 3267 unsigned NumArgs = args.size(); 3268 3269 // Since this might be a postfix expression, get rid of ParenListExprs. 3270 fn = MaybeConvertParenListExprToParenExpr(S, move(fn)); 3271 3272 Expr *Fn = fn.takeAs<Expr>(); 3273 Expr **Args = reinterpret_cast<Expr**>(args.release()); 3274 assert(Fn && "no function call expression"); 3275 3276 if (getLangOptions().CPlusPlus) { 3277 // If this is a pseudo-destructor expression, build the call immediately. 3278 if (isa<CXXPseudoDestructorExpr>(Fn)) { 3279 if (NumArgs > 0) { 3280 // Pseudo-destructor calls should not have any arguments. 3281 Diag(Fn->getLocStart(), diag::err_pseudo_dtor_call_with_args) 3282 << CodeModificationHint::CreateRemoval( 3283 SourceRange(Args[0]->getLocStart(), 3284 Args[NumArgs-1]->getLocEnd())); 3285 3286 for (unsigned I = 0; I != NumArgs; ++I) 3287 Args[I]->Destroy(Context); 3288 3289 NumArgs = 0; 3290 } 3291 3292 return Owned(new (Context) CallExpr(Context, Fn, 0, 0, Context.VoidTy, 3293 RParenLoc)); 3294 } 3295 3296 // Determine whether this is a dependent call inside a C++ template, 3297 // in which case we won't do any semantic analysis now. 3298 // FIXME: Will need to cache the results of name lookup (including ADL) in 3299 // Fn. 3300 bool Dependent = false; 3301 if (Fn->isTypeDependent()) 3302 Dependent = true; 3303 else if (Expr::hasAnyTypeDependentArguments(Args, NumArgs)) 3304 Dependent = true; 3305 3306 if (Dependent) 3307 return Owned(new (Context) CallExpr(Context, Fn, Args, NumArgs, 3308 Context.DependentTy, RParenLoc)); 3309 3310 // Determine whether this is a call to an object (C++ [over.call.object]). 3311 if (Fn->getType()->isRecordType()) 3312 return Owned(BuildCallToObjectOfClassType(S, Fn, LParenLoc, Args, NumArgs, 3313 CommaLocs, RParenLoc)); 3314 3315 Expr *NakedFn = Fn->IgnoreParens(); 3316 3317 // Determine whether this is a call to an unresolved member function. 3318 if (UnresolvedMemberExpr *MemE = dyn_cast<UnresolvedMemberExpr>(NakedFn)) { 3319 // If lookup was unresolved but not dependent (i.e. didn't find 3320 // an unresolved using declaration), it has to be an overloaded 3321 // function set, which means it must contain either multiple 3322 // declarations (all methods or method templates) or a single 3323 // method template. 3324 assert((MemE->getNumDecls() > 1) || 3325 isa<FunctionTemplateDecl>(*MemE->decls_begin())); 3326 (void)MemE; 3327 3328 return BuildCallToMemberFunction(S, Fn, LParenLoc, Args, NumArgs, 3329 CommaLocs, RParenLoc); 3330 } 3331 3332 // Determine whether this is a call to a member function. 3333 if (MemberExpr *MemExpr = dyn_cast<MemberExpr>(NakedFn)) { 3334 NamedDecl *MemDecl = MemExpr->getMemberDecl(); 3335 if (isa<CXXMethodDecl>(MemDecl)) 3336 return BuildCallToMemberFunction(S, Fn, LParenLoc, Args, NumArgs, 3337 CommaLocs, RParenLoc); 3338 } 3339 3340 // Determine whether this is a call to a pointer-to-member function. 3341 if (BinaryOperator *BO = dyn_cast<BinaryOperator>(NakedFn)) { 3342 if (BO->getOpcode() == BinaryOperator::PtrMemD || 3343 BO->getOpcode() == BinaryOperator::PtrMemI) { 3344 if (const FunctionProtoType *FPT = 3345 dyn_cast<FunctionProtoType>(BO->getType())) { 3346 QualType ResultTy = FPT->getResultType().getNonReferenceType(); 3347 3348 ExprOwningPtr<CXXMemberCallExpr> 3349 TheCall(this, new (Context) CXXMemberCallExpr(Context, BO, Args, 3350 NumArgs, ResultTy, 3351 RParenLoc)); 3352 3353 if (CheckCallReturnType(FPT->getResultType(), 3354 BO->getRHS()->getSourceRange().getBegin(), 3355 TheCall.get(), 0)) 3356 return ExprError(); 3357 3358 if (ConvertArgumentsForCall(&*TheCall, BO, 0, FPT, Args, NumArgs, 3359 RParenLoc)) 3360 return ExprError(); 3361 3362 return Owned(MaybeBindToTemporary(TheCall.release()).release()); 3363 } 3364 return ExprError(Diag(Fn->getLocStart(), 3365 diag::err_typecheck_call_not_function) 3366 << Fn->getType() << Fn->getSourceRange()); 3367 } 3368 } 3369 } 3370 3371 // If we're directly calling a function, get the appropriate declaration. 3372 // Also, in C++, keep track of whether we should perform argument-dependent 3373 // lookup and whether there were any explicitly-specified template arguments. 3374 llvm::SmallVector<NamedDecl*,8> Fns; 3375 DeclarationName UnqualifiedName; 3376 bool Overloaded; 3377 bool ADL; 3378 bool HasExplicitTemplateArgs = 0; 3379 TemplateArgumentListInfo ExplicitTemplateArgs; 3380 NestedNameSpecifier *Qualifier = 0; 3381 SourceRange QualifierRange; 3382 DeconstructCallFunction(Fn, Fns, UnqualifiedName, Qualifier, QualifierRange, 3383 ADL, Overloaded, HasExplicitTemplateArgs, 3384 ExplicitTemplateArgs); 3385 3386 NamedDecl *NDecl; // the specific declaration we're calling, if applicable 3387 FunctionDecl *FDecl; // same, if it's known to be a function 3388 3389 if (Overloaded || ADL) { 3390#ifndef NDEBUG 3391 if (ADL) { 3392 // To do ADL, we must have found an unqualified name. 3393 assert(UnqualifiedName && "found no unqualified name for ADL"); 3394 3395 // We don't perform ADL for implicit declarations of builtins. 3396 // Verify that this was correctly set up. 3397 if (Fns.size() == 1 && (FDecl = dyn_cast<FunctionDecl>(Fns[0])) && 3398 FDecl->getBuiltinID() && FDecl->isImplicit()) 3399 assert(0 && "performing ADL for builtin"); 3400 3401 // We don't perform ADL in C. 3402 assert(getLangOptions().CPlusPlus && "ADL enabled in C"); 3403 } 3404 3405 if (Overloaded) { 3406 // To be overloaded, we must either have multiple functions or 3407 // at least one function template (which is effectively an 3408 // infinite set of functions). 3409 assert((Fns.size() > 1 || 3410 (Fns.size() == 1 && 3411 isa<FunctionTemplateDecl>(Fns[0]->getUnderlyingDecl()))) 3412 && "unrecognized overload situation"); 3413 } 3414#endif 3415 3416 FDecl = ResolveOverloadedCallFn(Fn, Fns, UnqualifiedName, 3417 (HasExplicitTemplateArgs ? &ExplicitTemplateArgs : 0), 3418 LParenLoc, Args, NumArgs, CommaLocs, 3419 RParenLoc, ADL); 3420 if (!FDecl) 3421 return ExprError(); 3422 3423 Fn = FixOverloadedFunctionReference(Fn, FDecl); 3424 3425 NDecl = FDecl; 3426 } else { 3427 assert(Fns.size() <= 1 && "overloaded without Overloaded flag"); 3428 if (Fns.empty()) 3429 NDecl = 0; 3430 else { 3431 NDecl = Fns[0]; 3432 } 3433 } 3434 3435 return BuildResolvedCallExpr(Fn, NDecl, LParenLoc, Args, NumArgs, RParenLoc); 3436} 3437 3438/// BuildCallExpr - Build a call to a resolved expression, i.e. an 3439/// expression not of \p OverloadTy. The expression should 3440/// unary-convert to an expression of function-pointer or 3441/// block-pointer type. 3442/// 3443/// \param NDecl the declaration being called, if available 3444Sema::OwningExprResult 3445Sema::BuildResolvedCallExpr(Expr *Fn, NamedDecl *NDecl, 3446 SourceLocation LParenLoc, 3447 Expr **Args, unsigned NumArgs, 3448 SourceLocation RParenLoc) { 3449 FunctionDecl *FDecl = dyn_cast_or_null<FunctionDecl>(NDecl); 3450 3451 // Promote the function operand. 3452 UsualUnaryConversions(Fn); 3453 3454 // Make the call expr early, before semantic checks. This guarantees cleanup 3455 // of arguments and function on error. 3456 ExprOwningPtr<CallExpr> TheCall(this, new (Context) CallExpr(Context, Fn, 3457 Args, NumArgs, 3458 Context.BoolTy, 3459 RParenLoc)); 3460 3461 const FunctionType *FuncT; 3462 if (!Fn->getType()->isBlockPointerType()) { 3463 // C99 6.5.2.2p1 - "The expression that denotes the called function shall 3464 // have type pointer to function". 3465 const PointerType *PT = Fn->getType()->getAs<PointerType>(); 3466 if (PT == 0) 3467 return ExprError(Diag(LParenLoc, diag::err_typecheck_call_not_function) 3468 << Fn->getType() << Fn->getSourceRange()); 3469 FuncT = PT->getPointeeType()->getAs<FunctionType>(); 3470 } else { // This is a block call. 3471 FuncT = Fn->getType()->getAs<BlockPointerType>()->getPointeeType()-> 3472 getAs<FunctionType>(); 3473 } 3474 if (FuncT == 0) 3475 return ExprError(Diag(LParenLoc, diag::err_typecheck_call_not_function) 3476 << Fn->getType() << Fn->getSourceRange()); 3477 3478 // Check for a valid return type 3479 if (CheckCallReturnType(FuncT->getResultType(), 3480 Fn->getSourceRange().getBegin(), TheCall.get(), 3481 FDecl)) 3482 return ExprError(); 3483 3484 // We know the result type of the call, set it. 3485 TheCall->setType(FuncT->getResultType().getNonReferenceType()); 3486 3487 if (const FunctionProtoType *Proto = dyn_cast<FunctionProtoType>(FuncT)) { 3488 if (ConvertArgumentsForCall(&*TheCall, Fn, FDecl, Proto, Args, NumArgs, 3489 RParenLoc)) 3490 return ExprError(); 3491 } else { 3492 assert(isa<FunctionNoProtoType>(FuncT) && "Unknown FunctionType!"); 3493 3494 if (FDecl) { 3495 // Check if we have too few/too many template arguments, based 3496 // on our knowledge of the function definition. 3497 const FunctionDecl *Def = 0; 3498 if (FDecl->getBody(Def) && NumArgs != Def->param_size()) { 3499 const FunctionProtoType *Proto = 3500 Def->getType()->getAs<FunctionProtoType>(); 3501 if (!Proto || !(Proto->isVariadic() && NumArgs >= Def->param_size())) { 3502 Diag(RParenLoc, diag::warn_call_wrong_number_of_arguments) 3503 << (NumArgs > Def->param_size()) << FDecl << Fn->getSourceRange(); 3504 } 3505 } 3506 } 3507 3508 // Promote the arguments (C99 6.5.2.2p6). 3509 for (unsigned i = 0; i != NumArgs; i++) { 3510 Expr *Arg = Args[i]; 3511 DefaultArgumentPromotion(Arg); 3512 if (RequireCompleteType(Arg->getSourceRange().getBegin(), 3513 Arg->getType(), 3514 PDiag(diag::err_call_incomplete_argument) 3515 << Arg->getSourceRange())) 3516 return ExprError(); 3517 TheCall->setArg(i, Arg); 3518 } 3519 } 3520 3521 if (CXXMethodDecl *Method = dyn_cast_or_null<CXXMethodDecl>(FDecl)) 3522 if (!Method->isStatic()) 3523 return ExprError(Diag(LParenLoc, diag::err_member_call_without_object) 3524 << Fn->getSourceRange()); 3525 3526 // Check for sentinels 3527 if (NDecl) 3528 DiagnoseSentinelCalls(NDecl, LParenLoc, Args, NumArgs); 3529 3530 // Do special checking on direct calls to functions. 3531 if (FDecl) { 3532 if (CheckFunctionCall(FDecl, TheCall.get())) 3533 return ExprError(); 3534 3535 if (unsigned BuiltinID = FDecl->getBuiltinID()) 3536 return CheckBuiltinFunctionCall(BuiltinID, TheCall.take()); 3537 } else if (NDecl) { 3538 if (CheckBlockCall(NDecl, TheCall.get())) 3539 return ExprError(); 3540 } 3541 3542 return MaybeBindToTemporary(TheCall.take()); 3543} 3544 3545Action::OwningExprResult 3546Sema::ActOnCompoundLiteral(SourceLocation LParenLoc, TypeTy *Ty, 3547 SourceLocation RParenLoc, ExprArg InitExpr) { 3548 assert((Ty != 0) && "ActOnCompoundLiteral(): missing type"); 3549 //FIXME: Preserve type source info. 3550 QualType literalType = GetTypeFromParser(Ty); 3551 // FIXME: put back this assert when initializers are worked out. 3552 //assert((InitExpr != 0) && "ActOnCompoundLiteral(): missing expression"); 3553 Expr *literalExpr = static_cast<Expr*>(InitExpr.get()); 3554 3555 if (literalType->isArrayType()) { 3556 if (literalType->isVariableArrayType()) 3557 return ExprError(Diag(LParenLoc, diag::err_variable_object_no_init) 3558 << SourceRange(LParenLoc, literalExpr->getSourceRange().getEnd())); 3559 } else if (!literalType->isDependentType() && 3560 RequireCompleteType(LParenLoc, literalType, 3561 PDiag(diag::err_typecheck_decl_incomplete_type) 3562 << SourceRange(LParenLoc, 3563 literalExpr->getSourceRange().getEnd()))) 3564 return ExprError(); 3565 3566 if (CheckInitializerTypes(literalExpr, literalType, LParenLoc, 3567 DeclarationName(), /*FIXME:DirectInit=*/false)) 3568 return ExprError(); 3569 3570 bool isFileScope = getCurFunctionOrMethodDecl() == 0; 3571 if (isFileScope) { // 6.5.2.5p3 3572 if (CheckForConstantInitializer(literalExpr, literalType)) 3573 return ExprError(); 3574 } 3575 InitExpr.release(); 3576 return Owned(new (Context) CompoundLiteralExpr(LParenLoc, literalType, 3577 literalExpr, isFileScope)); 3578} 3579 3580Action::OwningExprResult 3581Sema::ActOnInitList(SourceLocation LBraceLoc, MultiExprArg initlist, 3582 SourceLocation RBraceLoc) { 3583 unsigned NumInit = initlist.size(); 3584 Expr **InitList = reinterpret_cast<Expr**>(initlist.release()); 3585 3586 // Semantic analysis for initializers is done by ActOnDeclarator() and 3587 // CheckInitializer() - it requires knowledge of the object being intialized. 3588 3589 InitListExpr *E = new (Context) InitListExpr(LBraceLoc, InitList, NumInit, 3590 RBraceLoc); 3591 E->setType(Context.VoidTy); // FIXME: just a place holder for now. 3592 return Owned(E); 3593} 3594 3595static CastExpr::CastKind getScalarCastKind(ASTContext &Context, 3596 QualType SrcTy, QualType DestTy) { 3597 if (Context.hasSameUnqualifiedType(SrcTy, DestTy)) 3598 return CastExpr::CK_NoOp; 3599 3600 if (SrcTy->hasPointerRepresentation()) { 3601 if (DestTy->hasPointerRepresentation()) 3602 return CastExpr::CK_BitCast; 3603 if (DestTy->isIntegerType()) 3604 return CastExpr::CK_PointerToIntegral; 3605 } 3606 3607 if (SrcTy->isIntegerType()) { 3608 if (DestTy->isIntegerType()) 3609 return CastExpr::CK_IntegralCast; 3610 if (DestTy->hasPointerRepresentation()) 3611 return CastExpr::CK_IntegralToPointer; 3612 if (DestTy->isRealFloatingType()) 3613 return CastExpr::CK_IntegralToFloating; 3614 } 3615 3616 if (SrcTy->isRealFloatingType()) { 3617 if (DestTy->isRealFloatingType()) 3618 return CastExpr::CK_FloatingCast; 3619 if (DestTy->isIntegerType()) 3620 return CastExpr::CK_FloatingToIntegral; 3621 } 3622 3623 // FIXME: Assert here. 3624 // assert(false && "Unhandled cast combination!"); 3625 return CastExpr::CK_Unknown; 3626} 3627 3628/// CheckCastTypes - Check type constraints for casting between types. 3629bool Sema::CheckCastTypes(SourceRange TyR, QualType castType, Expr *&castExpr, 3630 CastExpr::CastKind& Kind, 3631 CXXMethodDecl *& ConversionDecl, 3632 bool FunctionalStyle) { 3633 if (getLangOptions().CPlusPlus) 3634 return CXXCheckCStyleCast(TyR, castType, castExpr, Kind, FunctionalStyle, 3635 ConversionDecl); 3636 3637 DefaultFunctionArrayConversion(castExpr); 3638 3639 // C99 6.5.4p2: the cast type needs to be void or scalar and the expression 3640 // type needs to be scalar. 3641 if (castType->isVoidType()) { 3642 // Cast to void allows any expr type. 3643 Kind = CastExpr::CK_ToVoid; 3644 return false; 3645 } 3646 3647 if (!castType->isScalarType() && !castType->isVectorType()) { 3648 if (Context.hasSameUnqualifiedType(castType, castExpr->getType()) && 3649 (castType->isStructureType() || castType->isUnionType())) { 3650 // GCC struct/union extension: allow cast to self. 3651 // FIXME: Check that the cast destination type is complete. 3652 Diag(TyR.getBegin(), diag::ext_typecheck_cast_nonscalar) 3653 << castType << castExpr->getSourceRange(); 3654 Kind = CastExpr::CK_NoOp; 3655 return false; 3656 } 3657 3658 if (castType->isUnionType()) { 3659 // GCC cast to union extension 3660 RecordDecl *RD = castType->getAs<RecordType>()->getDecl(); 3661 RecordDecl::field_iterator Field, FieldEnd; 3662 for (Field = RD->field_begin(), FieldEnd = RD->field_end(); 3663 Field != FieldEnd; ++Field) { 3664 if (Context.hasSameUnqualifiedType(Field->getType(), 3665 castExpr->getType())) { 3666 Diag(TyR.getBegin(), diag::ext_typecheck_cast_to_union) 3667 << castExpr->getSourceRange(); 3668 break; 3669 } 3670 } 3671 if (Field == FieldEnd) 3672 return Diag(TyR.getBegin(), diag::err_typecheck_cast_to_union_no_type) 3673 << castExpr->getType() << castExpr->getSourceRange(); 3674 Kind = CastExpr::CK_ToUnion; 3675 return false; 3676 } 3677 3678 // Reject any other conversions to non-scalar types. 3679 return Diag(TyR.getBegin(), diag::err_typecheck_cond_expect_scalar) 3680 << castType << castExpr->getSourceRange(); 3681 } 3682 3683 if (!castExpr->getType()->isScalarType() && 3684 !castExpr->getType()->isVectorType()) { 3685 return Diag(castExpr->getLocStart(), 3686 diag::err_typecheck_expect_scalar_operand) 3687 << castExpr->getType() << castExpr->getSourceRange(); 3688 } 3689 3690 if (castType->isExtVectorType()) 3691 return CheckExtVectorCast(TyR, castType, castExpr, Kind); 3692 3693 if (castType->isVectorType()) 3694 return CheckVectorCast(TyR, castType, castExpr->getType(), Kind); 3695 if (castExpr->getType()->isVectorType()) 3696 return CheckVectorCast(TyR, castExpr->getType(), castType, Kind); 3697 3698 if (getLangOptions().ObjC1 && isa<ObjCSuperExpr>(castExpr)) 3699 return Diag(castExpr->getLocStart(), diag::err_illegal_super_cast) << TyR; 3700 3701 if (isa<ObjCSelectorExpr>(castExpr)) 3702 return Diag(castExpr->getLocStart(), diag::err_cast_selector_expr); 3703 3704 if (!castType->isArithmeticType()) { 3705 QualType castExprType = castExpr->getType(); 3706 if (!castExprType->isIntegralType() && castExprType->isArithmeticType()) 3707 return Diag(castExpr->getLocStart(), 3708 diag::err_cast_pointer_from_non_pointer_int) 3709 << castExprType << castExpr->getSourceRange(); 3710 } else if (!castExpr->getType()->isArithmeticType()) { 3711 if (!castType->isIntegralType() && castType->isArithmeticType()) 3712 return Diag(castExpr->getLocStart(), 3713 diag::err_cast_pointer_to_non_pointer_int) 3714 << castType << castExpr->getSourceRange(); 3715 } 3716 3717 Kind = getScalarCastKind(Context, castExpr->getType(), castType); 3718 return false; 3719} 3720 3721bool Sema::CheckVectorCast(SourceRange R, QualType VectorTy, QualType Ty, 3722 CastExpr::CastKind &Kind) { 3723 assert(VectorTy->isVectorType() && "Not a vector type!"); 3724 3725 if (Ty->isVectorType() || Ty->isIntegerType()) { 3726 if (Context.getTypeSize(VectorTy) != Context.getTypeSize(Ty)) 3727 return Diag(R.getBegin(), 3728 Ty->isVectorType() ? 3729 diag::err_invalid_conversion_between_vectors : 3730 diag::err_invalid_conversion_between_vector_and_integer) 3731 << VectorTy << Ty << R; 3732 } else 3733 return Diag(R.getBegin(), 3734 diag::err_invalid_conversion_between_vector_and_scalar) 3735 << VectorTy << Ty << R; 3736 3737 Kind = CastExpr::CK_BitCast; 3738 return false; 3739} 3740 3741bool Sema::CheckExtVectorCast(SourceRange R, QualType DestTy, Expr *&CastExpr, 3742 CastExpr::CastKind &Kind) { 3743 assert(DestTy->isExtVectorType() && "Not an extended vector type!"); 3744 3745 QualType SrcTy = CastExpr->getType(); 3746 3747 // If SrcTy is a VectorType, the total size must match to explicitly cast to 3748 // an ExtVectorType. 3749 if (SrcTy->isVectorType()) { 3750 if (Context.getTypeSize(DestTy) != Context.getTypeSize(SrcTy)) 3751 return Diag(R.getBegin(),diag::err_invalid_conversion_between_ext_vectors) 3752 << DestTy << SrcTy << R; 3753 Kind = CastExpr::CK_BitCast; 3754 return false; 3755 } 3756 3757 // All non-pointer scalars can be cast to ExtVector type. The appropriate 3758 // conversion will take place first from scalar to elt type, and then 3759 // splat from elt type to vector. 3760 if (SrcTy->isPointerType()) 3761 return Diag(R.getBegin(), 3762 diag::err_invalid_conversion_between_vector_and_scalar) 3763 << DestTy << SrcTy << R; 3764 3765 QualType DestElemTy = DestTy->getAs<ExtVectorType>()->getElementType(); 3766 ImpCastExprToType(CastExpr, DestElemTy, 3767 getScalarCastKind(Context, SrcTy, DestElemTy)); 3768 3769 Kind = CastExpr::CK_VectorSplat; 3770 return false; 3771} 3772 3773Action::OwningExprResult 3774Sema::ActOnCastExpr(Scope *S, SourceLocation LParenLoc, TypeTy *Ty, 3775 SourceLocation RParenLoc, ExprArg Op) { 3776 CastExpr::CastKind Kind = CastExpr::CK_Unknown; 3777 3778 assert((Ty != 0) && (Op.get() != 0) && 3779 "ActOnCastExpr(): missing type or expr"); 3780 3781 Expr *castExpr = (Expr *)Op.get(); 3782 //FIXME: Preserve type source info. 3783 QualType castType = GetTypeFromParser(Ty); 3784 3785 // If the Expr being casted is a ParenListExpr, handle it specially. 3786 if (isa<ParenListExpr>(castExpr)) 3787 return ActOnCastOfParenListExpr(S, LParenLoc, RParenLoc, move(Op),castType); 3788 CXXMethodDecl *Method = 0; 3789 if (CheckCastTypes(SourceRange(LParenLoc, RParenLoc), castType, castExpr, 3790 Kind, Method)) 3791 return ExprError(); 3792 3793 if (Method) { 3794 OwningExprResult CastArg = BuildCXXCastArgument(LParenLoc, castType, Kind, 3795 Method, move(Op)); 3796 3797 if (CastArg.isInvalid()) 3798 return ExprError(); 3799 3800 castExpr = CastArg.takeAs<Expr>(); 3801 } else { 3802 Op.release(); 3803 } 3804 3805 return Owned(new (Context) CStyleCastExpr(castType.getNonReferenceType(), 3806 Kind, castExpr, castType, 3807 LParenLoc, RParenLoc)); 3808} 3809 3810/// This is not an AltiVec-style cast, so turn the ParenListExpr into a sequence 3811/// of comma binary operators. 3812Action::OwningExprResult 3813Sema::MaybeConvertParenListExprToParenExpr(Scope *S, ExprArg EA) { 3814 Expr *expr = EA.takeAs<Expr>(); 3815 ParenListExpr *E = dyn_cast<ParenListExpr>(expr); 3816 if (!E) 3817 return Owned(expr); 3818 3819 OwningExprResult Result(*this, E->getExpr(0)); 3820 3821 for (unsigned i = 1, e = E->getNumExprs(); i != e && !Result.isInvalid(); ++i) 3822 Result = ActOnBinOp(S, E->getExprLoc(), tok::comma, move(Result), 3823 Owned(E->getExpr(i))); 3824 3825 return ActOnParenExpr(E->getLParenLoc(), E->getRParenLoc(), move(Result)); 3826} 3827 3828Action::OwningExprResult 3829Sema::ActOnCastOfParenListExpr(Scope *S, SourceLocation LParenLoc, 3830 SourceLocation RParenLoc, ExprArg Op, 3831 QualType Ty) { 3832 ParenListExpr *PE = (ParenListExpr *)Op.get(); 3833 3834 // If this is an altivec initializer, '(' type ')' '(' init, ..., init ')' 3835 // then handle it as such. 3836 if (getLangOptions().AltiVec && Ty->isVectorType()) { 3837 if (PE->getNumExprs() == 0) { 3838 Diag(PE->getExprLoc(), diag::err_altivec_empty_initializer); 3839 return ExprError(); 3840 } 3841 3842 llvm::SmallVector<Expr *, 8> initExprs; 3843 for (unsigned i = 0, e = PE->getNumExprs(); i != e; ++i) 3844 initExprs.push_back(PE->getExpr(i)); 3845 3846 // FIXME: This means that pretty-printing the final AST will produce curly 3847 // braces instead of the original commas. 3848 Op.release(); 3849 InitListExpr *E = new (Context) InitListExpr(LParenLoc, &initExprs[0], 3850 initExprs.size(), RParenLoc); 3851 E->setType(Ty); 3852 return ActOnCompoundLiteral(LParenLoc, Ty.getAsOpaquePtr(), RParenLoc, 3853 Owned(E)); 3854 } else { 3855 // This is not an AltiVec-style cast, so turn the ParenListExpr into a 3856 // sequence of BinOp comma operators. 3857 Op = MaybeConvertParenListExprToParenExpr(S, move(Op)); 3858 return ActOnCastExpr(S, LParenLoc, Ty.getAsOpaquePtr(), RParenLoc,move(Op)); 3859 } 3860} 3861 3862Action::OwningExprResult Sema::ActOnParenOrParenListExpr(SourceLocation L, 3863 SourceLocation R, 3864 MultiExprArg Val, 3865 TypeTy *TypeOfCast) { 3866 unsigned nexprs = Val.size(); 3867 Expr **exprs = reinterpret_cast<Expr**>(Val.release()); 3868 assert((exprs != 0) && "ActOnParenOrParenListExpr() missing expr list"); 3869 Expr *expr; 3870 if (nexprs == 1 && TypeOfCast && !TypeIsVectorType(TypeOfCast)) 3871 expr = new (Context) ParenExpr(L, R, exprs[0]); 3872 else 3873 expr = new (Context) ParenListExpr(Context, L, exprs, nexprs, R); 3874 return Owned(expr); 3875} 3876 3877/// Note that lhs is not null here, even if this is the gnu "x ?: y" extension. 3878/// In that case, lhs = cond. 3879/// C99 6.5.15 3880QualType Sema::CheckConditionalOperands(Expr *&Cond, Expr *&LHS, Expr *&RHS, 3881 SourceLocation QuestionLoc) { 3882 // C++ is sufficiently different to merit its own checker. 3883 if (getLangOptions().CPlusPlus) 3884 return CXXCheckConditionalOperands(Cond, LHS, RHS, QuestionLoc); 3885 3886 CheckSignCompare(LHS, RHS, QuestionLoc, diag::warn_mixed_sign_conditional); 3887 3888 UsualUnaryConversions(Cond); 3889 UsualUnaryConversions(LHS); 3890 UsualUnaryConversions(RHS); 3891 QualType CondTy = Cond->getType(); 3892 QualType LHSTy = LHS->getType(); 3893 QualType RHSTy = RHS->getType(); 3894 3895 // first, check the condition. 3896 if (!CondTy->isScalarType()) { // C99 6.5.15p2 3897 Diag(Cond->getLocStart(), diag::err_typecheck_cond_expect_scalar) 3898 << CondTy; 3899 return QualType(); 3900 } 3901 3902 // Now check the two expressions. 3903 if (LHSTy->isVectorType() || RHSTy->isVectorType()) 3904 return CheckVectorOperands(QuestionLoc, LHS, RHS); 3905 3906 // If both operands have arithmetic type, do the usual arithmetic conversions 3907 // to find a common type: C99 6.5.15p3,5. 3908 if (LHSTy->isArithmeticType() && RHSTy->isArithmeticType()) { 3909 UsualArithmeticConversions(LHS, RHS); 3910 return LHS->getType(); 3911 } 3912 3913 // If both operands are the same structure or union type, the result is that 3914 // type. 3915 if (const RecordType *LHSRT = LHSTy->getAs<RecordType>()) { // C99 6.5.15p3 3916 if (const RecordType *RHSRT = RHSTy->getAs<RecordType>()) 3917 if (LHSRT->getDecl() == RHSRT->getDecl()) 3918 // "If both the operands have structure or union type, the result has 3919 // that type." This implies that CV qualifiers are dropped. 3920 return LHSTy.getUnqualifiedType(); 3921 // FIXME: Type of conditional expression must be complete in C mode. 3922 } 3923 3924 // C99 6.5.15p5: "If both operands have void type, the result has void type." 3925 // The following || allows only one side to be void (a GCC-ism). 3926 if (LHSTy->isVoidType() || RHSTy->isVoidType()) { 3927 if (!LHSTy->isVoidType()) 3928 Diag(RHS->getLocStart(), diag::ext_typecheck_cond_one_void) 3929 << RHS->getSourceRange(); 3930 if (!RHSTy->isVoidType()) 3931 Diag(LHS->getLocStart(), diag::ext_typecheck_cond_one_void) 3932 << LHS->getSourceRange(); 3933 ImpCastExprToType(LHS, Context.VoidTy, CastExpr::CK_ToVoid); 3934 ImpCastExprToType(RHS, Context.VoidTy, CastExpr::CK_ToVoid); 3935 return Context.VoidTy; 3936 } 3937 // C99 6.5.15p6 - "if one operand is a null pointer constant, the result has 3938 // the type of the other operand." 3939 if ((LHSTy->isAnyPointerType() || LHSTy->isBlockPointerType()) && 3940 RHS->isNullPointerConstant(Context, Expr::NPC_ValueDependentIsNull)) { 3941 // promote the null to a pointer. 3942 ImpCastExprToType(RHS, LHSTy, CastExpr::CK_Unknown); 3943 return LHSTy; 3944 } 3945 if ((RHSTy->isAnyPointerType() || RHSTy->isBlockPointerType()) && 3946 LHS->isNullPointerConstant(Context, Expr::NPC_ValueDependentIsNull)) { 3947 ImpCastExprToType(LHS, RHSTy, CastExpr::CK_Unknown); 3948 return RHSTy; 3949 } 3950 3951 // All objective-c pointer type analysis is done here. 3952 QualType compositeType = FindCompositeObjCPointerType(LHS, RHS, 3953 QuestionLoc); 3954 if (!compositeType.isNull()) 3955 return compositeType; 3956 3957 3958 // Handle block pointer types. 3959 if (LHSTy->isBlockPointerType() || RHSTy->isBlockPointerType()) { 3960 if (!LHSTy->isBlockPointerType() || !RHSTy->isBlockPointerType()) { 3961 if (LHSTy->isVoidPointerType() || RHSTy->isVoidPointerType()) { 3962 QualType destType = Context.getPointerType(Context.VoidTy); 3963 ImpCastExprToType(LHS, destType, CastExpr::CK_BitCast); 3964 ImpCastExprToType(RHS, destType, CastExpr::CK_BitCast); 3965 return destType; 3966 } 3967 Diag(QuestionLoc, diag::err_typecheck_cond_incompatible_operands) 3968 << LHSTy << RHSTy << LHS->getSourceRange() << RHS->getSourceRange(); 3969 return QualType(); 3970 } 3971 // We have 2 block pointer types. 3972 if (Context.getCanonicalType(LHSTy) == Context.getCanonicalType(RHSTy)) { 3973 // Two identical block pointer types are always compatible. 3974 return LHSTy; 3975 } 3976 // The block pointer types aren't identical, continue checking. 3977 QualType lhptee = LHSTy->getAs<BlockPointerType>()->getPointeeType(); 3978 QualType rhptee = RHSTy->getAs<BlockPointerType>()->getPointeeType(); 3979 3980 if (!Context.typesAreCompatible(lhptee.getUnqualifiedType(), 3981 rhptee.getUnqualifiedType())) { 3982 Diag(QuestionLoc, diag::warn_typecheck_cond_incompatible_pointers) 3983 << LHSTy << RHSTy << LHS->getSourceRange() << RHS->getSourceRange(); 3984 // In this situation, we assume void* type. No especially good 3985 // reason, but this is what gcc does, and we do have to pick 3986 // to get a consistent AST. 3987 QualType incompatTy = Context.getPointerType(Context.VoidTy); 3988 ImpCastExprToType(LHS, incompatTy, CastExpr::CK_BitCast); 3989 ImpCastExprToType(RHS, incompatTy, CastExpr::CK_BitCast); 3990 return incompatTy; 3991 } 3992 // The block pointer types are compatible. 3993 ImpCastExprToType(LHS, LHSTy, CastExpr::CK_BitCast); 3994 ImpCastExprToType(RHS, LHSTy, CastExpr::CK_BitCast); 3995 return LHSTy; 3996 } 3997 3998 // Check constraints for C object pointers types (C99 6.5.15p3,6). 3999 if (LHSTy->isPointerType() && RHSTy->isPointerType()) { 4000 // get the "pointed to" types 4001 QualType lhptee = LHSTy->getAs<PointerType>()->getPointeeType(); 4002 QualType rhptee = RHSTy->getAs<PointerType>()->getPointeeType(); 4003 4004 // ignore qualifiers on void (C99 6.5.15p3, clause 6) 4005 if (lhptee->isVoidType() && rhptee->isIncompleteOrObjectType()) { 4006 // Figure out necessary qualifiers (C99 6.5.15p6) 4007 QualType destPointee 4008 = Context.getQualifiedType(lhptee, rhptee.getQualifiers()); 4009 QualType destType = Context.getPointerType(destPointee); 4010 // Add qualifiers if necessary. 4011 ImpCastExprToType(LHS, destType, CastExpr::CK_NoOp); 4012 // Promote to void*. 4013 ImpCastExprToType(RHS, destType, CastExpr::CK_BitCast); 4014 return destType; 4015 } 4016 if (rhptee->isVoidType() && lhptee->isIncompleteOrObjectType()) { 4017 QualType destPointee 4018 = Context.getQualifiedType(rhptee, lhptee.getQualifiers()); 4019 QualType destType = Context.getPointerType(destPointee); 4020 // Add qualifiers if necessary. 4021 ImpCastExprToType(RHS, destType, CastExpr::CK_NoOp); 4022 // Promote to void*. 4023 ImpCastExprToType(LHS, destType, CastExpr::CK_BitCast); 4024 return destType; 4025 } 4026 4027 if (Context.getCanonicalType(LHSTy) == Context.getCanonicalType(RHSTy)) { 4028 // Two identical pointer types are always compatible. 4029 return LHSTy; 4030 } 4031 if (!Context.typesAreCompatible(lhptee.getUnqualifiedType(), 4032 rhptee.getUnqualifiedType())) { 4033 Diag(QuestionLoc, diag::warn_typecheck_cond_incompatible_pointers) 4034 << LHSTy << RHSTy << LHS->getSourceRange() << RHS->getSourceRange(); 4035 // In this situation, we assume void* type. No especially good 4036 // reason, but this is what gcc does, and we do have to pick 4037 // to get a consistent AST. 4038 QualType incompatTy = Context.getPointerType(Context.VoidTy); 4039 ImpCastExprToType(LHS, incompatTy, CastExpr::CK_BitCast); 4040 ImpCastExprToType(RHS, incompatTy, CastExpr::CK_BitCast); 4041 return incompatTy; 4042 } 4043 // The pointer types are compatible. 4044 // C99 6.5.15p6: If both operands are pointers to compatible types *or* to 4045 // differently qualified versions of compatible types, the result type is 4046 // a pointer to an appropriately qualified version of the *composite* 4047 // type. 4048 // FIXME: Need to calculate the composite type. 4049 // FIXME: Need to add qualifiers 4050 ImpCastExprToType(LHS, LHSTy, CastExpr::CK_BitCast); 4051 ImpCastExprToType(RHS, LHSTy, CastExpr::CK_BitCast); 4052 return LHSTy; 4053 } 4054 4055 // GCC compatibility: soften pointer/integer mismatch. 4056 if (RHSTy->isPointerType() && LHSTy->isIntegerType()) { 4057 Diag(QuestionLoc, diag::warn_typecheck_cond_pointer_integer_mismatch) 4058 << LHSTy << RHSTy << LHS->getSourceRange() << RHS->getSourceRange(); 4059 ImpCastExprToType(LHS, RHSTy, CastExpr::CK_IntegralToPointer); 4060 return RHSTy; 4061 } 4062 if (LHSTy->isPointerType() && RHSTy->isIntegerType()) { 4063 Diag(QuestionLoc, diag::warn_typecheck_cond_pointer_integer_mismatch) 4064 << LHSTy << RHSTy << LHS->getSourceRange() << RHS->getSourceRange(); 4065 ImpCastExprToType(RHS, LHSTy, CastExpr::CK_IntegralToPointer); 4066 return LHSTy; 4067 } 4068 4069 // Otherwise, the operands are not compatible. 4070 Diag(QuestionLoc, diag::err_typecheck_cond_incompatible_operands) 4071 << LHSTy << RHSTy << LHS->getSourceRange() << RHS->getSourceRange(); 4072 return QualType(); 4073} 4074 4075/// FindCompositeObjCPointerType - Helper method to find composite type of 4076/// two objective-c pointer types of the two input expressions. 4077QualType Sema::FindCompositeObjCPointerType(Expr *&LHS, Expr *&RHS, 4078 SourceLocation QuestionLoc) { 4079 QualType LHSTy = LHS->getType(); 4080 QualType RHSTy = RHS->getType(); 4081 4082 // Handle things like Class and struct objc_class*. Here we case the result 4083 // to the pseudo-builtin, because that will be implicitly cast back to the 4084 // redefinition type if an attempt is made to access its fields. 4085 if (LHSTy->isObjCClassType() && 4086 (RHSTy.getDesugaredType() == Context.ObjCClassRedefinitionType)) { 4087 ImpCastExprToType(RHS, LHSTy, CastExpr::CK_BitCast); 4088 return LHSTy; 4089 } 4090 if (RHSTy->isObjCClassType() && 4091 (LHSTy.getDesugaredType() == Context.ObjCClassRedefinitionType)) { 4092 ImpCastExprToType(LHS, RHSTy, CastExpr::CK_BitCast); 4093 return RHSTy; 4094 } 4095 // And the same for struct objc_object* / id 4096 if (LHSTy->isObjCIdType() && 4097 (RHSTy.getDesugaredType() == Context.ObjCIdRedefinitionType)) { 4098 ImpCastExprToType(RHS, LHSTy, CastExpr::CK_BitCast); 4099 return LHSTy; 4100 } 4101 if (RHSTy->isObjCIdType() && 4102 (LHSTy.getDesugaredType() == Context.ObjCIdRedefinitionType)) { 4103 ImpCastExprToType(LHS, RHSTy, CastExpr::CK_BitCast); 4104 return RHSTy; 4105 } 4106 // And the same for struct objc_selector* / SEL 4107 if (Context.isObjCSelType(LHSTy) && 4108 (RHSTy.getDesugaredType() == Context.ObjCSelRedefinitionType)) { 4109 ImpCastExprToType(RHS, LHSTy, CastExpr::CK_BitCast); 4110 return LHSTy; 4111 } 4112 if (Context.isObjCSelType(RHSTy) && 4113 (LHSTy.getDesugaredType() == Context.ObjCSelRedefinitionType)) { 4114 ImpCastExprToType(LHS, RHSTy, CastExpr::CK_BitCast); 4115 return RHSTy; 4116 } 4117 // Check constraints for Objective-C object pointers types. 4118 if (LHSTy->isObjCObjectPointerType() && RHSTy->isObjCObjectPointerType()) { 4119 4120 if (Context.getCanonicalType(LHSTy) == Context.getCanonicalType(RHSTy)) { 4121 // Two identical object pointer types are always compatible. 4122 return LHSTy; 4123 } 4124 const ObjCObjectPointerType *LHSOPT = LHSTy->getAs<ObjCObjectPointerType>(); 4125 const ObjCObjectPointerType *RHSOPT = RHSTy->getAs<ObjCObjectPointerType>(); 4126 QualType compositeType = LHSTy; 4127 4128 // If both operands are interfaces and either operand can be 4129 // assigned to the other, use that type as the composite 4130 // type. This allows 4131 // xxx ? (A*) a : (B*) b 4132 // where B is a subclass of A. 4133 // 4134 // Additionally, as for assignment, if either type is 'id' 4135 // allow silent coercion. Finally, if the types are 4136 // incompatible then make sure to use 'id' as the composite 4137 // type so the result is acceptable for sending messages to. 4138 4139 // FIXME: Consider unifying with 'areComparableObjCPointerTypes'. 4140 // It could return the composite type. 4141 if (Context.canAssignObjCInterfaces(LHSOPT, RHSOPT)) { 4142 compositeType = RHSOPT->isObjCBuiltinType() ? RHSTy : LHSTy; 4143 } else if (Context.canAssignObjCInterfaces(RHSOPT, LHSOPT)) { 4144 compositeType = LHSOPT->isObjCBuiltinType() ? LHSTy : RHSTy; 4145 } else if ((LHSTy->isObjCQualifiedIdType() || 4146 RHSTy->isObjCQualifiedIdType()) && 4147 Context.ObjCQualifiedIdTypesAreCompatible(LHSTy, RHSTy, true)) { 4148 // Need to handle "id<xx>" explicitly. 4149 // GCC allows qualified id and any Objective-C type to devolve to 4150 // id. Currently localizing to here until clear this should be 4151 // part of ObjCQualifiedIdTypesAreCompatible. 4152 compositeType = Context.getObjCIdType(); 4153 } else if (LHSTy->isObjCIdType() || RHSTy->isObjCIdType()) { 4154 compositeType = Context.getObjCIdType(); 4155 } else if (!(compositeType = 4156 Context.areCommonBaseCompatible(LHSOPT, RHSOPT)).isNull()) 4157 ; 4158 else { 4159 Diag(QuestionLoc, diag::ext_typecheck_cond_incompatible_operands) 4160 << LHSTy << RHSTy 4161 << LHS->getSourceRange() << RHS->getSourceRange(); 4162 QualType incompatTy = Context.getObjCIdType(); 4163 ImpCastExprToType(LHS, incompatTy, CastExpr::CK_BitCast); 4164 ImpCastExprToType(RHS, incompatTy, CastExpr::CK_BitCast); 4165 return incompatTy; 4166 } 4167 // The object pointer types are compatible. 4168 ImpCastExprToType(LHS, compositeType, CastExpr::CK_BitCast); 4169 ImpCastExprToType(RHS, compositeType, CastExpr::CK_BitCast); 4170 return compositeType; 4171 } 4172 // Check Objective-C object pointer types and 'void *' 4173 if (LHSTy->isVoidPointerType() && RHSTy->isObjCObjectPointerType()) { 4174 QualType lhptee = LHSTy->getAs<PointerType>()->getPointeeType(); 4175 QualType rhptee = RHSTy->getAs<ObjCObjectPointerType>()->getPointeeType(); 4176 QualType destPointee 4177 = Context.getQualifiedType(lhptee, rhptee.getQualifiers()); 4178 QualType destType = Context.getPointerType(destPointee); 4179 // Add qualifiers if necessary. 4180 ImpCastExprToType(LHS, destType, CastExpr::CK_NoOp); 4181 // Promote to void*. 4182 ImpCastExprToType(RHS, destType, CastExpr::CK_BitCast); 4183 return destType; 4184 } 4185 if (LHSTy->isObjCObjectPointerType() && RHSTy->isVoidPointerType()) { 4186 QualType lhptee = LHSTy->getAs<ObjCObjectPointerType>()->getPointeeType(); 4187 QualType rhptee = RHSTy->getAs<PointerType>()->getPointeeType(); 4188 QualType destPointee 4189 = Context.getQualifiedType(rhptee, lhptee.getQualifiers()); 4190 QualType destType = Context.getPointerType(destPointee); 4191 // Add qualifiers if necessary. 4192 ImpCastExprToType(RHS, destType, CastExpr::CK_NoOp); 4193 // Promote to void*. 4194 ImpCastExprToType(LHS, destType, CastExpr::CK_BitCast); 4195 return destType; 4196 } 4197 return QualType(); 4198} 4199 4200/// ActOnConditionalOp - Parse a ?: operation. Note that 'LHS' may be null 4201/// in the case of a the GNU conditional expr extension. 4202Action::OwningExprResult Sema::ActOnConditionalOp(SourceLocation QuestionLoc, 4203 SourceLocation ColonLoc, 4204 ExprArg Cond, ExprArg LHS, 4205 ExprArg RHS) { 4206 Expr *CondExpr = (Expr *) Cond.get(); 4207 Expr *LHSExpr = (Expr *) LHS.get(), *RHSExpr = (Expr *) RHS.get(); 4208 4209 // If this is the gnu "x ?: y" extension, analyze the types as though the LHS 4210 // was the condition. 4211 bool isLHSNull = LHSExpr == 0; 4212 if (isLHSNull) 4213 LHSExpr = CondExpr; 4214 4215 QualType result = CheckConditionalOperands(CondExpr, LHSExpr, 4216 RHSExpr, QuestionLoc); 4217 if (result.isNull()) 4218 return ExprError(); 4219 4220 Cond.release(); 4221 LHS.release(); 4222 RHS.release(); 4223 return Owned(new (Context) ConditionalOperator(CondExpr, QuestionLoc, 4224 isLHSNull ? 0 : LHSExpr, 4225 ColonLoc, RHSExpr, result)); 4226} 4227 4228// CheckPointerTypesForAssignment - This is a very tricky routine (despite 4229// being closely modeled after the C99 spec:-). The odd characteristic of this 4230// routine is it effectively iqnores the qualifiers on the top level pointee. 4231// This circumvents the usual type rules specified in 6.2.7p1 & 6.7.5.[1-3]. 4232// FIXME: add a couple examples in this comment. 4233Sema::AssignConvertType 4234Sema::CheckPointerTypesForAssignment(QualType lhsType, QualType rhsType) { 4235 QualType lhptee, rhptee; 4236 4237 if ((lhsType->isObjCClassType() && 4238 (rhsType.getDesugaredType() == Context.ObjCClassRedefinitionType)) || 4239 (rhsType->isObjCClassType() && 4240 (lhsType.getDesugaredType() == Context.ObjCClassRedefinitionType))) { 4241 return Compatible; 4242 } 4243 4244 // get the "pointed to" type (ignoring qualifiers at the top level) 4245 lhptee = lhsType->getAs<PointerType>()->getPointeeType(); 4246 rhptee = rhsType->getAs<PointerType>()->getPointeeType(); 4247 4248 // make sure we operate on the canonical type 4249 lhptee = Context.getCanonicalType(lhptee); 4250 rhptee = Context.getCanonicalType(rhptee); 4251 4252 AssignConvertType ConvTy = Compatible; 4253 4254 // C99 6.5.16.1p1: This following citation is common to constraints 4255 // 3 & 4 (below). ...and the type *pointed to* by the left has all the 4256 // qualifiers of the type *pointed to* by the right; 4257 // FIXME: Handle ExtQualType 4258 if (!lhptee.isAtLeastAsQualifiedAs(rhptee)) 4259 ConvTy = CompatiblePointerDiscardsQualifiers; 4260 4261 // C99 6.5.16.1p1 (constraint 4): If one operand is a pointer to an object or 4262 // incomplete type and the other is a pointer to a qualified or unqualified 4263 // version of void... 4264 if (lhptee->isVoidType()) { 4265 if (rhptee->isIncompleteOrObjectType()) 4266 return ConvTy; 4267 4268 // As an extension, we allow cast to/from void* to function pointer. 4269 assert(rhptee->isFunctionType()); 4270 return FunctionVoidPointer; 4271 } 4272 4273 if (rhptee->isVoidType()) { 4274 if (lhptee->isIncompleteOrObjectType()) 4275 return ConvTy; 4276 4277 // As an extension, we allow cast to/from void* to function pointer. 4278 assert(lhptee->isFunctionType()); 4279 return FunctionVoidPointer; 4280 } 4281 // C99 6.5.16.1p1 (constraint 3): both operands are pointers to qualified or 4282 // unqualified versions of compatible types, ... 4283 lhptee = lhptee.getUnqualifiedType(); 4284 rhptee = rhptee.getUnqualifiedType(); 4285 if (!Context.typesAreCompatible(lhptee, rhptee)) { 4286 // Check if the pointee types are compatible ignoring the sign. 4287 // We explicitly check for char so that we catch "char" vs 4288 // "unsigned char" on systems where "char" is unsigned. 4289 if (lhptee->isCharType()) 4290 lhptee = Context.UnsignedCharTy; 4291 else if (lhptee->isSignedIntegerType()) 4292 lhptee = Context.getCorrespondingUnsignedType(lhptee); 4293 4294 if (rhptee->isCharType()) 4295 rhptee = Context.UnsignedCharTy; 4296 else if (rhptee->isSignedIntegerType()) 4297 rhptee = Context.getCorrespondingUnsignedType(rhptee); 4298 4299 if (lhptee == rhptee) { 4300 // Types are compatible ignoring the sign. Qualifier incompatibility 4301 // takes priority over sign incompatibility because the sign 4302 // warning can be disabled. 4303 if (ConvTy != Compatible) 4304 return ConvTy; 4305 return IncompatiblePointerSign; 4306 } 4307 4308 // If we are a multi-level pointer, it's possible that our issue is simply 4309 // one of qualification - e.g. char ** -> const char ** is not allowed. If 4310 // the eventual target type is the same and the pointers have the same 4311 // level of indirection, this must be the issue. 4312 if (lhptee->isPointerType() && rhptee->isPointerType()) { 4313 do { 4314 lhptee = lhptee->getAs<PointerType>()->getPointeeType(); 4315 rhptee = rhptee->getAs<PointerType>()->getPointeeType(); 4316 4317 lhptee = Context.getCanonicalType(lhptee); 4318 rhptee = Context.getCanonicalType(rhptee); 4319 } while (lhptee->isPointerType() && rhptee->isPointerType()); 4320 4321 if (Context.hasSameUnqualifiedType(lhptee, rhptee)) 4322 return IncompatibleNestedPointerQualifiers; 4323 } 4324 4325 // General pointer incompatibility takes priority over qualifiers. 4326 return IncompatiblePointer; 4327 } 4328 return ConvTy; 4329} 4330 4331/// CheckBlockPointerTypesForAssignment - This routine determines whether two 4332/// block pointer types are compatible or whether a block and normal pointer 4333/// are compatible. It is more restrict than comparing two function pointer 4334// types. 4335Sema::AssignConvertType 4336Sema::CheckBlockPointerTypesForAssignment(QualType lhsType, 4337 QualType rhsType) { 4338 QualType lhptee, rhptee; 4339 4340 // get the "pointed to" type (ignoring qualifiers at the top level) 4341 lhptee = lhsType->getAs<BlockPointerType>()->getPointeeType(); 4342 rhptee = rhsType->getAs<BlockPointerType>()->getPointeeType(); 4343 4344 // make sure we operate on the canonical type 4345 lhptee = Context.getCanonicalType(lhptee); 4346 rhptee = Context.getCanonicalType(rhptee); 4347 4348 AssignConvertType ConvTy = Compatible; 4349 4350 // For blocks we enforce that qualifiers are identical. 4351 if (lhptee.getLocalCVRQualifiers() != rhptee.getLocalCVRQualifiers()) 4352 ConvTy = CompatiblePointerDiscardsQualifiers; 4353 4354 if (!Context.typesAreCompatible(lhptee, rhptee)) 4355 return IncompatibleBlockPointer; 4356 return ConvTy; 4357} 4358 4359/// CheckObjCPointerTypesForAssignment - Compares two objective-c pointer types 4360/// for assignment compatibility. 4361Sema::AssignConvertType 4362Sema::CheckObjCPointerTypesForAssignment(QualType lhsType, QualType rhsType) { 4363 if (lhsType->isObjCBuiltinType() || rhsType->isObjCBuiltinType()) 4364 return Compatible; 4365 QualType lhptee = 4366 lhsType->getAs<ObjCObjectPointerType>()->getPointeeType(); 4367 QualType rhptee = 4368 rhsType->getAs<ObjCObjectPointerType>()->getPointeeType(); 4369 // make sure we operate on the canonical type 4370 lhptee = Context.getCanonicalType(lhptee); 4371 rhptee = Context.getCanonicalType(rhptee); 4372 if (!lhptee.isAtLeastAsQualifiedAs(rhptee)) 4373 return CompatiblePointerDiscardsQualifiers; 4374 4375 if (Context.typesAreCompatible(lhsType, rhsType)) 4376 return Compatible; 4377 if (lhsType->isObjCQualifiedIdType() || rhsType->isObjCQualifiedIdType()) 4378 return IncompatibleObjCQualifiedId; 4379 return IncompatiblePointer; 4380} 4381 4382/// CheckAssignmentConstraints (C99 6.5.16) - This routine currently 4383/// has code to accommodate several GCC extensions when type checking 4384/// pointers. Here are some objectionable examples that GCC considers warnings: 4385/// 4386/// int a, *pint; 4387/// short *pshort; 4388/// struct foo *pfoo; 4389/// 4390/// pint = pshort; // warning: assignment from incompatible pointer type 4391/// a = pint; // warning: assignment makes integer from pointer without a cast 4392/// pint = a; // warning: assignment makes pointer from integer without a cast 4393/// pint = pfoo; // warning: assignment from incompatible pointer type 4394/// 4395/// As a result, the code for dealing with pointers is more complex than the 4396/// C99 spec dictates. 4397/// 4398Sema::AssignConvertType 4399Sema::CheckAssignmentConstraints(QualType lhsType, QualType rhsType) { 4400 // Get canonical types. We're not formatting these types, just comparing 4401 // them. 4402 lhsType = Context.getCanonicalType(lhsType).getUnqualifiedType(); 4403 rhsType = Context.getCanonicalType(rhsType).getUnqualifiedType(); 4404 4405 if (lhsType == rhsType) 4406 return Compatible; // Common case: fast path an exact match. 4407 4408 if ((lhsType->isObjCClassType() && 4409 (rhsType.getDesugaredType() == Context.ObjCClassRedefinitionType)) || 4410 (rhsType->isObjCClassType() && 4411 (lhsType.getDesugaredType() == Context.ObjCClassRedefinitionType))) { 4412 return Compatible; 4413 } 4414 4415 // If the left-hand side is a reference type, then we are in a 4416 // (rare!) case where we've allowed the use of references in C, 4417 // e.g., as a parameter type in a built-in function. In this case, 4418 // just make sure that the type referenced is compatible with the 4419 // right-hand side type. The caller is responsible for adjusting 4420 // lhsType so that the resulting expression does not have reference 4421 // type. 4422 if (const ReferenceType *lhsTypeRef = lhsType->getAs<ReferenceType>()) { 4423 if (Context.typesAreCompatible(lhsTypeRef->getPointeeType(), rhsType)) 4424 return Compatible; 4425 return Incompatible; 4426 } 4427 // Allow scalar to ExtVector assignments, and assignments of an ExtVector type 4428 // to the same ExtVector type. 4429 if (lhsType->isExtVectorType()) { 4430 if (rhsType->isExtVectorType()) 4431 return lhsType == rhsType ? Compatible : Incompatible; 4432 if (!rhsType->isVectorType() && rhsType->isArithmeticType()) 4433 return Compatible; 4434 } 4435 4436 if (lhsType->isVectorType() || rhsType->isVectorType()) { 4437 // If we are allowing lax vector conversions, and LHS and RHS are both 4438 // vectors, the total size only needs to be the same. This is a bitcast; 4439 // no bits are changed but the result type is different. 4440 if (getLangOptions().LaxVectorConversions && 4441 lhsType->isVectorType() && rhsType->isVectorType()) { 4442 if (Context.getTypeSize(lhsType) == Context.getTypeSize(rhsType)) 4443 return IncompatibleVectors; 4444 } 4445 return Incompatible; 4446 } 4447 4448 if (lhsType->isArithmeticType() && rhsType->isArithmeticType()) 4449 return Compatible; 4450 4451 if (isa<PointerType>(lhsType)) { 4452 if (rhsType->isIntegerType()) 4453 return IntToPointer; 4454 4455 if (isa<PointerType>(rhsType)) 4456 return CheckPointerTypesForAssignment(lhsType, rhsType); 4457 4458 // In general, C pointers are not compatible with ObjC object pointers. 4459 if (isa<ObjCObjectPointerType>(rhsType)) { 4460 if (lhsType->isVoidPointerType()) // an exception to the rule. 4461 return Compatible; 4462 return IncompatiblePointer; 4463 } 4464 if (rhsType->getAs<BlockPointerType>()) { 4465 if (lhsType->getAs<PointerType>()->getPointeeType()->isVoidType()) 4466 return Compatible; 4467 4468 // Treat block pointers as objects. 4469 if (getLangOptions().ObjC1 && lhsType->isObjCIdType()) 4470 return Compatible; 4471 } 4472 return Incompatible; 4473 } 4474 4475 if (isa<BlockPointerType>(lhsType)) { 4476 if (rhsType->isIntegerType()) 4477 return IntToBlockPointer; 4478 4479 // Treat block pointers as objects. 4480 if (getLangOptions().ObjC1 && rhsType->isObjCIdType()) 4481 return Compatible; 4482 4483 if (rhsType->isBlockPointerType()) 4484 return CheckBlockPointerTypesForAssignment(lhsType, rhsType); 4485 4486 if (const PointerType *RHSPT = rhsType->getAs<PointerType>()) { 4487 if (RHSPT->getPointeeType()->isVoidType()) 4488 return Compatible; 4489 } 4490 return Incompatible; 4491 } 4492 4493 if (isa<ObjCObjectPointerType>(lhsType)) { 4494 if (rhsType->isIntegerType()) 4495 return IntToPointer; 4496 4497 // In general, C pointers are not compatible with ObjC object pointers. 4498 if (isa<PointerType>(rhsType)) { 4499 if (rhsType->isVoidPointerType()) // an exception to the rule. 4500 return Compatible; 4501 return IncompatiblePointer; 4502 } 4503 if (rhsType->isObjCObjectPointerType()) { 4504 return CheckObjCPointerTypesForAssignment(lhsType, rhsType); 4505 } 4506 if (const PointerType *RHSPT = rhsType->getAs<PointerType>()) { 4507 if (RHSPT->getPointeeType()->isVoidType()) 4508 return Compatible; 4509 } 4510 // Treat block pointers as objects. 4511 if (rhsType->isBlockPointerType()) 4512 return Compatible; 4513 return Incompatible; 4514 } 4515 if (isa<PointerType>(rhsType)) { 4516 // C99 6.5.16.1p1: the left operand is _Bool and the right is a pointer. 4517 if (lhsType == Context.BoolTy) 4518 return Compatible; 4519 4520 if (lhsType->isIntegerType()) 4521 return PointerToInt; 4522 4523 if (isa<PointerType>(lhsType)) 4524 return CheckPointerTypesForAssignment(lhsType, rhsType); 4525 4526 if (isa<BlockPointerType>(lhsType) && 4527 rhsType->getAs<PointerType>()->getPointeeType()->isVoidType()) 4528 return Compatible; 4529 return Incompatible; 4530 } 4531 if (isa<ObjCObjectPointerType>(rhsType)) { 4532 // C99 6.5.16.1p1: the left operand is _Bool and the right is a pointer. 4533 if (lhsType == Context.BoolTy) 4534 return Compatible; 4535 4536 if (lhsType->isIntegerType()) 4537 return PointerToInt; 4538 4539 // In general, C pointers are not compatible with ObjC object pointers. 4540 if (isa<PointerType>(lhsType)) { 4541 if (lhsType->isVoidPointerType()) // an exception to the rule. 4542 return Compatible; 4543 return IncompatiblePointer; 4544 } 4545 if (isa<BlockPointerType>(lhsType) && 4546 rhsType->getAs<PointerType>()->getPointeeType()->isVoidType()) 4547 return Compatible; 4548 return Incompatible; 4549 } 4550 4551 if (isa<TagType>(lhsType) && isa<TagType>(rhsType)) { 4552 if (Context.typesAreCompatible(lhsType, rhsType)) 4553 return Compatible; 4554 } 4555 return Incompatible; 4556} 4557 4558/// \brief Constructs a transparent union from an expression that is 4559/// used to initialize the transparent union. 4560static void ConstructTransparentUnion(ASTContext &C, Expr *&E, 4561 QualType UnionType, FieldDecl *Field) { 4562 // Build an initializer list that designates the appropriate member 4563 // of the transparent union. 4564 InitListExpr *Initializer = new (C) InitListExpr(SourceLocation(), 4565 &E, 1, 4566 SourceLocation()); 4567 Initializer->setType(UnionType); 4568 Initializer->setInitializedFieldInUnion(Field); 4569 4570 // Build a compound literal constructing a value of the transparent 4571 // union type from this initializer list. 4572 E = new (C) CompoundLiteralExpr(SourceLocation(), UnionType, Initializer, 4573 false); 4574} 4575 4576Sema::AssignConvertType 4577Sema::CheckTransparentUnionArgumentConstraints(QualType ArgType, Expr *&rExpr) { 4578 QualType FromType = rExpr->getType(); 4579 4580 // If the ArgType is a Union type, we want to handle a potential 4581 // transparent_union GCC extension. 4582 const RecordType *UT = ArgType->getAsUnionType(); 4583 if (!UT || !UT->getDecl()->hasAttr<TransparentUnionAttr>()) 4584 return Incompatible; 4585 4586 // The field to initialize within the transparent union. 4587 RecordDecl *UD = UT->getDecl(); 4588 FieldDecl *InitField = 0; 4589 // It's compatible if the expression matches any of the fields. 4590 for (RecordDecl::field_iterator it = UD->field_begin(), 4591 itend = UD->field_end(); 4592 it != itend; ++it) { 4593 if (it->getType()->isPointerType()) { 4594 // If the transparent union contains a pointer type, we allow: 4595 // 1) void pointer 4596 // 2) null pointer constant 4597 if (FromType->isPointerType()) 4598 if (FromType->getAs<PointerType>()->getPointeeType()->isVoidType()) { 4599 ImpCastExprToType(rExpr, it->getType(), CastExpr::CK_BitCast); 4600 InitField = *it; 4601 break; 4602 } 4603 4604 if (rExpr->isNullPointerConstant(Context, 4605 Expr::NPC_ValueDependentIsNull)) { 4606 ImpCastExprToType(rExpr, it->getType(), CastExpr::CK_IntegralToPointer); 4607 InitField = *it; 4608 break; 4609 } 4610 } 4611 4612 if (CheckAssignmentConstraints(it->getType(), rExpr->getType()) 4613 == Compatible) { 4614 InitField = *it; 4615 break; 4616 } 4617 } 4618 4619 if (!InitField) 4620 return Incompatible; 4621 4622 ConstructTransparentUnion(Context, rExpr, ArgType, InitField); 4623 return Compatible; 4624} 4625 4626Sema::AssignConvertType 4627Sema::CheckSingleAssignmentConstraints(QualType lhsType, Expr *&rExpr) { 4628 if (getLangOptions().CPlusPlus) { 4629 if (!lhsType->isRecordType()) { 4630 // C++ 5.17p3: If the left operand is not of class type, the 4631 // expression is implicitly converted (C++ 4) to the 4632 // cv-unqualified type of the left operand. 4633 if (PerformImplicitConversion(rExpr, lhsType.getUnqualifiedType(), 4634 "assigning")) 4635 return Incompatible; 4636 return Compatible; 4637 } 4638 4639 // FIXME: Currently, we fall through and treat C++ classes like C 4640 // structures. 4641 } 4642 4643 // C99 6.5.16.1p1: the left operand is a pointer and the right is 4644 // a null pointer constant. 4645 if ((lhsType->isPointerType() || 4646 lhsType->isObjCObjectPointerType() || 4647 lhsType->isBlockPointerType()) 4648 && rExpr->isNullPointerConstant(Context, 4649 Expr::NPC_ValueDependentIsNull)) { 4650 ImpCastExprToType(rExpr, lhsType, CastExpr::CK_Unknown); 4651 return Compatible; 4652 } 4653 4654 // This check seems unnatural, however it is necessary to ensure the proper 4655 // conversion of functions/arrays. If the conversion were done for all 4656 // DeclExpr's (created by ActOnIdExpression), it would mess up the unary 4657 // expressions that surpress this implicit conversion (&, sizeof). 4658 // 4659 // Suppress this for references: C++ 8.5.3p5. 4660 if (!lhsType->isReferenceType()) 4661 DefaultFunctionArrayConversion(rExpr); 4662 4663 Sema::AssignConvertType result = 4664 CheckAssignmentConstraints(lhsType, rExpr->getType()); 4665 4666 // C99 6.5.16.1p2: The value of the right operand is converted to the 4667 // type of the assignment expression. 4668 // CheckAssignmentConstraints allows the left-hand side to be a reference, 4669 // so that we can use references in built-in functions even in C. 4670 // The getNonReferenceType() call makes sure that the resulting expression 4671 // does not have reference type. 4672 if (result != Incompatible && rExpr->getType() != lhsType) 4673 ImpCastExprToType(rExpr, lhsType.getNonReferenceType(), 4674 CastExpr::CK_Unknown); 4675 return result; 4676} 4677 4678QualType Sema::InvalidOperands(SourceLocation Loc, Expr *&lex, Expr *&rex) { 4679 Diag(Loc, diag::err_typecheck_invalid_operands) 4680 << lex->getType() << rex->getType() 4681 << lex->getSourceRange() << rex->getSourceRange(); 4682 return QualType(); 4683} 4684 4685inline QualType Sema::CheckVectorOperands(SourceLocation Loc, Expr *&lex, 4686 Expr *&rex) { 4687 // For conversion purposes, we ignore any qualifiers. 4688 // For example, "const float" and "float" are equivalent. 4689 QualType lhsType = 4690 Context.getCanonicalType(lex->getType()).getUnqualifiedType(); 4691 QualType rhsType = 4692 Context.getCanonicalType(rex->getType()).getUnqualifiedType(); 4693 4694 // If the vector types are identical, return. 4695 if (lhsType == rhsType) 4696 return lhsType; 4697 4698 // Handle the case of a vector & extvector type of the same size and element 4699 // type. It would be nice if we only had one vector type someday. 4700 if (getLangOptions().LaxVectorConversions) { 4701 // FIXME: Should we warn here? 4702 if (const VectorType *LV = lhsType->getAs<VectorType>()) { 4703 if (const VectorType *RV = rhsType->getAs<VectorType>()) 4704 if (LV->getElementType() == RV->getElementType() && 4705 LV->getNumElements() == RV->getNumElements()) { 4706 return lhsType->isExtVectorType() ? lhsType : rhsType; 4707 } 4708 } 4709 } 4710 4711 // Canonicalize the ExtVector to the LHS, remember if we swapped so we can 4712 // swap back (so that we don't reverse the inputs to a subtract, for instance. 4713 bool swapped = false; 4714 if (rhsType->isExtVectorType()) { 4715 swapped = true; 4716 std::swap(rex, lex); 4717 std::swap(rhsType, lhsType); 4718 } 4719 4720 // Handle the case of an ext vector and scalar. 4721 if (const ExtVectorType *LV = lhsType->getAs<ExtVectorType>()) { 4722 QualType EltTy = LV->getElementType(); 4723 if (EltTy->isIntegralType() && rhsType->isIntegralType()) { 4724 if (Context.getIntegerTypeOrder(EltTy, rhsType) >= 0) { 4725 ImpCastExprToType(rex, lhsType, CastExpr::CK_IntegralCast); 4726 if (swapped) std::swap(rex, lex); 4727 return lhsType; 4728 } 4729 } 4730 if (EltTy->isRealFloatingType() && rhsType->isScalarType() && 4731 rhsType->isRealFloatingType()) { 4732 if (Context.getFloatingTypeOrder(EltTy, rhsType) >= 0) { 4733 ImpCastExprToType(rex, lhsType, CastExpr::CK_FloatingCast); 4734 if (swapped) std::swap(rex, lex); 4735 return lhsType; 4736 } 4737 } 4738 } 4739 4740 // Vectors of different size or scalar and non-ext-vector are errors. 4741 Diag(Loc, diag::err_typecheck_vector_not_convertable) 4742 << lex->getType() << rex->getType() 4743 << lex->getSourceRange() << rex->getSourceRange(); 4744 return QualType(); 4745} 4746 4747inline QualType Sema::CheckMultiplyDivideOperands( 4748 Expr *&lex, Expr *&rex, SourceLocation Loc, bool isCompAssign) { 4749 if (lex->getType()->isVectorType() || rex->getType()->isVectorType()) 4750 return CheckVectorOperands(Loc, lex, rex); 4751 4752 QualType compType = UsualArithmeticConversions(lex, rex, isCompAssign); 4753 4754 if (lex->getType()->isArithmeticType() && rex->getType()->isArithmeticType()) 4755 return compType; 4756 return InvalidOperands(Loc, lex, rex); 4757} 4758 4759inline QualType Sema::CheckRemainderOperands( 4760 Expr *&lex, Expr *&rex, SourceLocation Loc, bool isCompAssign) { 4761 if (lex->getType()->isVectorType() || rex->getType()->isVectorType()) { 4762 if (lex->getType()->isIntegerType() && rex->getType()->isIntegerType()) 4763 return CheckVectorOperands(Loc, lex, rex); 4764 return InvalidOperands(Loc, lex, rex); 4765 } 4766 4767 QualType compType = UsualArithmeticConversions(lex, rex, isCompAssign); 4768 4769 if (lex->getType()->isIntegerType() && rex->getType()->isIntegerType()) 4770 return compType; 4771 return InvalidOperands(Loc, lex, rex); 4772} 4773 4774inline QualType Sema::CheckAdditionOperands( // C99 6.5.6 4775 Expr *&lex, Expr *&rex, SourceLocation Loc, QualType* CompLHSTy) { 4776 if (lex->getType()->isVectorType() || rex->getType()->isVectorType()) { 4777 QualType compType = CheckVectorOperands(Loc, lex, rex); 4778 if (CompLHSTy) *CompLHSTy = compType; 4779 return compType; 4780 } 4781 4782 QualType compType = UsualArithmeticConversions(lex, rex, CompLHSTy); 4783 4784 // handle the common case first (both operands are arithmetic). 4785 if (lex->getType()->isArithmeticType() && 4786 rex->getType()->isArithmeticType()) { 4787 if (CompLHSTy) *CompLHSTy = compType; 4788 return compType; 4789 } 4790 4791 // Put any potential pointer into PExp 4792 Expr* PExp = lex, *IExp = rex; 4793 if (IExp->getType()->isAnyPointerType()) 4794 std::swap(PExp, IExp); 4795 4796 if (PExp->getType()->isAnyPointerType()) { 4797 4798 if (IExp->getType()->isIntegerType()) { 4799 QualType PointeeTy = PExp->getType()->getPointeeType(); 4800 4801 // Check for arithmetic on pointers to incomplete types. 4802 if (PointeeTy->isVoidType()) { 4803 if (getLangOptions().CPlusPlus) { 4804 Diag(Loc, diag::err_typecheck_pointer_arith_void_type) 4805 << lex->getSourceRange() << rex->getSourceRange(); 4806 return QualType(); 4807 } 4808 4809 // GNU extension: arithmetic on pointer to void 4810 Diag(Loc, diag::ext_gnu_void_ptr) 4811 << lex->getSourceRange() << rex->getSourceRange(); 4812 } else if (PointeeTy->isFunctionType()) { 4813 if (getLangOptions().CPlusPlus) { 4814 Diag(Loc, diag::err_typecheck_pointer_arith_function_type) 4815 << lex->getType() << lex->getSourceRange(); 4816 return QualType(); 4817 } 4818 4819 // GNU extension: arithmetic on pointer to function 4820 Diag(Loc, diag::ext_gnu_ptr_func_arith) 4821 << lex->getType() << lex->getSourceRange(); 4822 } else { 4823 // Check if we require a complete type. 4824 if (((PExp->getType()->isPointerType() && 4825 !PExp->getType()->isDependentType()) || 4826 PExp->getType()->isObjCObjectPointerType()) && 4827 RequireCompleteType(Loc, PointeeTy, 4828 PDiag(diag::err_typecheck_arithmetic_incomplete_type) 4829 << PExp->getSourceRange() 4830 << PExp->getType())) 4831 return QualType(); 4832 } 4833 // Diagnose bad cases where we step over interface counts. 4834 if (PointeeTy->isObjCInterfaceType() && LangOpts.ObjCNonFragileABI) { 4835 Diag(Loc, diag::err_arithmetic_nonfragile_interface) 4836 << PointeeTy << PExp->getSourceRange(); 4837 return QualType(); 4838 } 4839 4840 if (CompLHSTy) { 4841 QualType LHSTy = Context.isPromotableBitField(lex); 4842 if (LHSTy.isNull()) { 4843 LHSTy = lex->getType(); 4844 if (LHSTy->isPromotableIntegerType()) 4845 LHSTy = Context.getPromotedIntegerType(LHSTy); 4846 } 4847 *CompLHSTy = LHSTy; 4848 } 4849 return PExp->getType(); 4850 } 4851 } 4852 4853 return InvalidOperands(Loc, lex, rex); 4854} 4855 4856// C99 6.5.6 4857QualType Sema::CheckSubtractionOperands(Expr *&lex, Expr *&rex, 4858 SourceLocation Loc, QualType* CompLHSTy) { 4859 if (lex->getType()->isVectorType() || rex->getType()->isVectorType()) { 4860 QualType compType = CheckVectorOperands(Loc, lex, rex); 4861 if (CompLHSTy) *CompLHSTy = compType; 4862 return compType; 4863 } 4864 4865 QualType compType = UsualArithmeticConversions(lex, rex, CompLHSTy); 4866 4867 // Enforce type constraints: C99 6.5.6p3. 4868 4869 // Handle the common case first (both operands are arithmetic). 4870 if (lex->getType()->isArithmeticType() 4871 && rex->getType()->isArithmeticType()) { 4872 if (CompLHSTy) *CompLHSTy = compType; 4873 return compType; 4874 } 4875 4876 // Either ptr - int or ptr - ptr. 4877 if (lex->getType()->isAnyPointerType()) { 4878 QualType lpointee = lex->getType()->getPointeeType(); 4879 4880 // The LHS must be an completely-defined object type. 4881 4882 bool ComplainAboutVoid = false; 4883 Expr *ComplainAboutFunc = 0; 4884 if (lpointee->isVoidType()) { 4885 if (getLangOptions().CPlusPlus) { 4886 Diag(Loc, diag::err_typecheck_pointer_arith_void_type) 4887 << lex->getSourceRange() << rex->getSourceRange(); 4888 return QualType(); 4889 } 4890 4891 // GNU C extension: arithmetic on pointer to void 4892 ComplainAboutVoid = true; 4893 } else if (lpointee->isFunctionType()) { 4894 if (getLangOptions().CPlusPlus) { 4895 Diag(Loc, diag::err_typecheck_pointer_arith_function_type) 4896 << lex->getType() << lex->getSourceRange(); 4897 return QualType(); 4898 } 4899 4900 // GNU C extension: arithmetic on pointer to function 4901 ComplainAboutFunc = lex; 4902 } else if (!lpointee->isDependentType() && 4903 RequireCompleteType(Loc, lpointee, 4904 PDiag(diag::err_typecheck_sub_ptr_object) 4905 << lex->getSourceRange() 4906 << lex->getType())) 4907 return QualType(); 4908 4909 // Diagnose bad cases where we step over interface counts. 4910 if (lpointee->isObjCInterfaceType() && LangOpts.ObjCNonFragileABI) { 4911 Diag(Loc, diag::err_arithmetic_nonfragile_interface) 4912 << lpointee << lex->getSourceRange(); 4913 return QualType(); 4914 } 4915 4916 // The result type of a pointer-int computation is the pointer type. 4917 if (rex->getType()->isIntegerType()) { 4918 if (ComplainAboutVoid) 4919 Diag(Loc, diag::ext_gnu_void_ptr) 4920 << lex->getSourceRange() << rex->getSourceRange(); 4921 if (ComplainAboutFunc) 4922 Diag(Loc, diag::ext_gnu_ptr_func_arith) 4923 << ComplainAboutFunc->getType() 4924 << ComplainAboutFunc->getSourceRange(); 4925 4926 if (CompLHSTy) *CompLHSTy = lex->getType(); 4927 return lex->getType(); 4928 } 4929 4930 // Handle pointer-pointer subtractions. 4931 if (const PointerType *RHSPTy = rex->getType()->getAs<PointerType>()) { 4932 QualType rpointee = RHSPTy->getPointeeType(); 4933 4934 // RHS must be a completely-type object type. 4935 // Handle the GNU void* extension. 4936 if (rpointee->isVoidType()) { 4937 if (getLangOptions().CPlusPlus) { 4938 Diag(Loc, diag::err_typecheck_pointer_arith_void_type) 4939 << lex->getSourceRange() << rex->getSourceRange(); 4940 return QualType(); 4941 } 4942 4943 ComplainAboutVoid = true; 4944 } else if (rpointee->isFunctionType()) { 4945 if (getLangOptions().CPlusPlus) { 4946 Diag(Loc, diag::err_typecheck_pointer_arith_function_type) 4947 << rex->getType() << rex->getSourceRange(); 4948 return QualType(); 4949 } 4950 4951 // GNU extension: arithmetic on pointer to function 4952 if (!ComplainAboutFunc) 4953 ComplainAboutFunc = rex; 4954 } else if (!rpointee->isDependentType() && 4955 RequireCompleteType(Loc, rpointee, 4956 PDiag(diag::err_typecheck_sub_ptr_object) 4957 << rex->getSourceRange() 4958 << rex->getType())) 4959 return QualType(); 4960 4961 if (getLangOptions().CPlusPlus) { 4962 // Pointee types must be the same: C++ [expr.add] 4963 if (!Context.hasSameUnqualifiedType(lpointee, rpointee)) { 4964 Diag(Loc, diag::err_typecheck_sub_ptr_compatible) 4965 << lex->getType() << rex->getType() 4966 << lex->getSourceRange() << rex->getSourceRange(); 4967 return QualType(); 4968 } 4969 } else { 4970 // Pointee types must be compatible C99 6.5.6p3 4971 if (!Context.typesAreCompatible( 4972 Context.getCanonicalType(lpointee).getUnqualifiedType(), 4973 Context.getCanonicalType(rpointee).getUnqualifiedType())) { 4974 Diag(Loc, diag::err_typecheck_sub_ptr_compatible) 4975 << lex->getType() << rex->getType() 4976 << lex->getSourceRange() << rex->getSourceRange(); 4977 return QualType(); 4978 } 4979 } 4980 4981 if (ComplainAboutVoid) 4982 Diag(Loc, diag::ext_gnu_void_ptr) 4983 << lex->getSourceRange() << rex->getSourceRange(); 4984 if (ComplainAboutFunc) 4985 Diag(Loc, diag::ext_gnu_ptr_func_arith) 4986 << ComplainAboutFunc->getType() 4987 << ComplainAboutFunc->getSourceRange(); 4988 4989 if (CompLHSTy) *CompLHSTy = lex->getType(); 4990 return Context.getPointerDiffType(); 4991 } 4992 } 4993 4994 return InvalidOperands(Loc, lex, rex); 4995} 4996 4997// C99 6.5.7 4998QualType Sema::CheckShiftOperands(Expr *&lex, Expr *&rex, SourceLocation Loc, 4999 bool isCompAssign) { 5000 // C99 6.5.7p2: Each of the operands shall have integer type. 5001 if (!lex->getType()->isIntegerType() || !rex->getType()->isIntegerType()) 5002 return InvalidOperands(Loc, lex, rex); 5003 5004 // Vector shifts promote their scalar inputs to vector type. 5005 if (lex->getType()->isVectorType() || rex->getType()->isVectorType()) 5006 return CheckVectorOperands(Loc, lex, rex); 5007 5008 // Shifts don't perform usual arithmetic conversions, they just do integer 5009 // promotions on each operand. C99 6.5.7p3 5010 QualType LHSTy = Context.isPromotableBitField(lex); 5011 if (LHSTy.isNull()) { 5012 LHSTy = lex->getType(); 5013 if (LHSTy->isPromotableIntegerType()) 5014 LHSTy = Context.getPromotedIntegerType(LHSTy); 5015 } 5016 if (!isCompAssign) 5017 ImpCastExprToType(lex, LHSTy, CastExpr::CK_IntegralCast); 5018 5019 UsualUnaryConversions(rex); 5020 5021 // Sanity-check shift operands 5022 llvm::APSInt Right; 5023 // Check right/shifter operand 5024 if (!rex->isValueDependent() && 5025 rex->isIntegerConstantExpr(Right, Context)) { 5026 if (Right.isNegative()) 5027 Diag(Loc, diag::warn_shift_negative) << rex->getSourceRange(); 5028 else { 5029 llvm::APInt LeftBits(Right.getBitWidth(), 5030 Context.getTypeSize(lex->getType())); 5031 if (Right.uge(LeftBits)) 5032 Diag(Loc, diag::warn_shift_gt_typewidth) << rex->getSourceRange(); 5033 } 5034 } 5035 5036 // "The type of the result is that of the promoted left operand." 5037 return LHSTy; 5038} 5039 5040/// \brief Implements -Wsign-compare. 5041/// 5042/// \param lex the left-hand expression 5043/// \param rex the right-hand expression 5044/// \param OpLoc the location of the joining operator 5045/// \param Equality whether this is an "equality-like" join, which 5046/// suppresses the warning in some cases 5047void Sema::CheckSignCompare(Expr *lex, Expr *rex, SourceLocation OpLoc, 5048 const PartialDiagnostic &PD, bool Equality) { 5049 // Don't warn if we're in an unevaluated context. 5050 if (ExprEvalContexts.back().Context == Unevaluated) 5051 return; 5052 5053 QualType lt = lex->getType(), rt = rex->getType(); 5054 5055 // Only warn if both operands are integral. 5056 if (!lt->isIntegerType() || !rt->isIntegerType()) 5057 return; 5058 5059 // If either expression is value-dependent, don't warn. We'll get another 5060 // chance at instantiation time. 5061 if (lex->isValueDependent() || rex->isValueDependent()) 5062 return; 5063 5064 // The rule is that the signed operand becomes unsigned, so isolate the 5065 // signed operand. 5066 Expr *signedOperand, *unsignedOperand; 5067 if (lt->isSignedIntegerType()) { 5068 if (rt->isSignedIntegerType()) return; 5069 signedOperand = lex; 5070 unsignedOperand = rex; 5071 } else { 5072 if (!rt->isSignedIntegerType()) return; 5073 signedOperand = rex; 5074 unsignedOperand = lex; 5075 } 5076 5077 // If the unsigned type is strictly smaller than the signed type, 5078 // then (1) the result type will be signed and (2) the unsigned 5079 // value will fit fully within the signed type, and thus the result 5080 // of the comparison will be exact. 5081 if (Context.getIntWidth(signedOperand->getType()) > 5082 Context.getIntWidth(unsignedOperand->getType())) 5083 return; 5084 5085 // If the value is a non-negative integer constant, then the 5086 // signed->unsigned conversion won't change it. 5087 llvm::APSInt value; 5088 if (signedOperand->isIntegerConstantExpr(value, Context)) { 5089 assert(value.isSigned() && "result of signed expression not signed"); 5090 5091 if (value.isNonNegative()) 5092 return; 5093 } 5094 5095 if (Equality) { 5096 // For (in)equality comparisons, if the unsigned operand is a 5097 // constant which cannot collide with a overflowed signed operand, 5098 // then reinterpreting the signed operand as unsigned will not 5099 // change the result of the comparison. 5100 if (unsignedOperand->isIntegerConstantExpr(value, Context)) { 5101 assert(!value.isSigned() && "result of unsigned expression is signed"); 5102 5103 // 2's complement: test the top bit. 5104 if (value.isNonNegative()) 5105 return; 5106 } 5107 } 5108 5109 Diag(OpLoc, PD) 5110 << lex->getType() << rex->getType() 5111 << lex->getSourceRange() << rex->getSourceRange(); 5112} 5113 5114// C99 6.5.8, C++ [expr.rel] 5115QualType Sema::CheckCompareOperands(Expr *&lex, Expr *&rex, SourceLocation Loc, 5116 unsigned OpaqueOpc, bool isRelational) { 5117 BinaryOperator::Opcode Opc = (BinaryOperator::Opcode)OpaqueOpc; 5118 5119 // Handle vector comparisons separately. 5120 if (lex->getType()->isVectorType() || rex->getType()->isVectorType()) 5121 return CheckVectorCompareOperands(lex, rex, Loc, isRelational); 5122 5123 CheckSignCompare(lex, rex, Loc, diag::warn_mixed_sign_comparison, 5124 (Opc == BinaryOperator::EQ || Opc == BinaryOperator::NE)); 5125 5126 // C99 6.5.8p3 / C99 6.5.9p4 5127 if (lex->getType()->isArithmeticType() && rex->getType()->isArithmeticType()) 5128 UsualArithmeticConversions(lex, rex); 5129 else { 5130 UsualUnaryConversions(lex); 5131 UsualUnaryConversions(rex); 5132 } 5133 QualType lType = lex->getType(); 5134 QualType rType = rex->getType(); 5135 5136 if (!lType->isFloatingType() 5137 && !(lType->isBlockPointerType() && isRelational)) { 5138 // For non-floating point types, check for self-comparisons of the form 5139 // x == x, x != x, x < x, etc. These always evaluate to a constant, and 5140 // often indicate logic errors in the program. 5141 // NOTE: Don't warn about comparisons of enum constants. These can arise 5142 // from macro expansions, and are usually quite deliberate. 5143 Expr *LHSStripped = lex->IgnoreParens(); 5144 Expr *RHSStripped = rex->IgnoreParens(); 5145 if (DeclRefExpr* DRL = dyn_cast<DeclRefExpr>(LHSStripped)) 5146 if (DeclRefExpr* DRR = dyn_cast<DeclRefExpr>(RHSStripped)) 5147 if (DRL->getDecl() == DRR->getDecl() && 5148 !isa<EnumConstantDecl>(DRL->getDecl())) 5149 Diag(Loc, diag::warn_selfcomparison); 5150 5151 if (isa<CastExpr>(LHSStripped)) 5152 LHSStripped = LHSStripped->IgnoreParenCasts(); 5153 if (isa<CastExpr>(RHSStripped)) 5154 RHSStripped = RHSStripped->IgnoreParenCasts(); 5155 5156 // Warn about comparisons against a string constant (unless the other 5157 // operand is null), the user probably wants strcmp. 5158 Expr *literalString = 0; 5159 Expr *literalStringStripped = 0; 5160 if ((isa<StringLiteral>(LHSStripped) || isa<ObjCEncodeExpr>(LHSStripped)) && 5161 !RHSStripped->isNullPointerConstant(Context, 5162 Expr::NPC_ValueDependentIsNull)) { 5163 literalString = lex; 5164 literalStringStripped = LHSStripped; 5165 } else if ((isa<StringLiteral>(RHSStripped) || 5166 isa<ObjCEncodeExpr>(RHSStripped)) && 5167 !LHSStripped->isNullPointerConstant(Context, 5168 Expr::NPC_ValueDependentIsNull)) { 5169 literalString = rex; 5170 literalStringStripped = RHSStripped; 5171 } 5172 5173 if (literalString) { 5174 std::string resultComparison; 5175 switch (Opc) { 5176 case BinaryOperator::LT: resultComparison = ") < 0"; break; 5177 case BinaryOperator::GT: resultComparison = ") > 0"; break; 5178 case BinaryOperator::LE: resultComparison = ") <= 0"; break; 5179 case BinaryOperator::GE: resultComparison = ") >= 0"; break; 5180 case BinaryOperator::EQ: resultComparison = ") == 0"; break; 5181 case BinaryOperator::NE: resultComparison = ") != 0"; break; 5182 default: assert(false && "Invalid comparison operator"); 5183 } 5184 Diag(Loc, diag::warn_stringcompare) 5185 << isa<ObjCEncodeExpr>(literalStringStripped) 5186 << literalString->getSourceRange() 5187 << CodeModificationHint::CreateReplacement(SourceRange(Loc), ", ") 5188 << CodeModificationHint::CreateInsertion(lex->getLocStart(), 5189 "strcmp(") 5190 << CodeModificationHint::CreateInsertion( 5191 PP.getLocForEndOfToken(rex->getLocEnd()), 5192 resultComparison); 5193 } 5194 } 5195 5196 // The result of comparisons is 'bool' in C++, 'int' in C. 5197 QualType ResultTy = getLangOptions().CPlusPlus ? Context.BoolTy:Context.IntTy; 5198 5199 if (isRelational) { 5200 if (lType->isRealType() && rType->isRealType()) 5201 return ResultTy; 5202 } else { 5203 // Check for comparisons of floating point operands using != and ==. 5204 if (lType->isFloatingType() && rType->isFloatingType()) 5205 CheckFloatComparison(Loc,lex,rex); 5206 5207 if (lType->isArithmeticType() && rType->isArithmeticType()) 5208 return ResultTy; 5209 } 5210 5211 bool LHSIsNull = lex->isNullPointerConstant(Context, 5212 Expr::NPC_ValueDependentIsNull); 5213 bool RHSIsNull = rex->isNullPointerConstant(Context, 5214 Expr::NPC_ValueDependentIsNull); 5215 5216 // All of the following pointer related warnings are GCC extensions, except 5217 // when handling null pointer constants. One day, we can consider making them 5218 // errors (when -pedantic-errors is enabled). 5219 if (lType->isPointerType() && rType->isPointerType()) { // C99 6.5.8p2 5220 QualType LCanPointeeTy = 5221 Context.getCanonicalType(lType->getAs<PointerType>()->getPointeeType()); 5222 QualType RCanPointeeTy = 5223 Context.getCanonicalType(rType->getAs<PointerType>()->getPointeeType()); 5224 5225 if (getLangOptions().CPlusPlus) { 5226 if (LCanPointeeTy == RCanPointeeTy) 5227 return ResultTy; 5228 5229 // C++ [expr.rel]p2: 5230 // [...] Pointer conversions (4.10) and qualification 5231 // conversions (4.4) are performed on pointer operands (or on 5232 // a pointer operand and a null pointer constant) to bring 5233 // them to their composite pointer type. [...] 5234 // 5235 // C++ [expr.eq]p1 uses the same notion for (in)equality 5236 // comparisons of pointers. 5237 QualType T = FindCompositePointerType(lex, rex); 5238 if (T.isNull()) { 5239 Diag(Loc, diag::err_typecheck_comparison_of_distinct_pointers) 5240 << lType << rType << lex->getSourceRange() << rex->getSourceRange(); 5241 return QualType(); 5242 } 5243 5244 ImpCastExprToType(lex, T, CastExpr::CK_BitCast); 5245 ImpCastExprToType(rex, T, CastExpr::CK_BitCast); 5246 return ResultTy; 5247 } 5248 // C99 6.5.9p2 and C99 6.5.8p2 5249 if (Context.typesAreCompatible(LCanPointeeTy.getUnqualifiedType(), 5250 RCanPointeeTy.getUnqualifiedType())) { 5251 // Valid unless a relational comparison of function pointers 5252 if (isRelational && LCanPointeeTy->isFunctionType()) { 5253 Diag(Loc, diag::ext_typecheck_ordered_comparison_of_function_pointers) 5254 << lType << rType << lex->getSourceRange() << rex->getSourceRange(); 5255 } 5256 } else if (!isRelational && 5257 (LCanPointeeTy->isVoidType() || RCanPointeeTy->isVoidType())) { 5258 // Valid unless comparison between non-null pointer and function pointer 5259 if ((LCanPointeeTy->isFunctionType() || RCanPointeeTy->isFunctionType()) 5260 && !LHSIsNull && !RHSIsNull) { 5261 Diag(Loc, diag::ext_typecheck_comparison_of_fptr_to_void) 5262 << lType << rType << lex->getSourceRange() << rex->getSourceRange(); 5263 } 5264 } else { 5265 // Invalid 5266 Diag(Loc, diag::ext_typecheck_comparison_of_distinct_pointers) 5267 << lType << rType << lex->getSourceRange() << rex->getSourceRange(); 5268 } 5269 if (LCanPointeeTy != RCanPointeeTy) 5270 ImpCastExprToType(rex, lType, CastExpr::CK_BitCast); 5271 return ResultTy; 5272 } 5273 5274 if (getLangOptions().CPlusPlus) { 5275 // Comparison of pointers with null pointer constants and equality 5276 // comparisons of member pointers to null pointer constants. 5277 if (RHSIsNull && 5278 (lType->isPointerType() || 5279 (!isRelational && lType->isMemberPointerType()))) { 5280 ImpCastExprToType(rex, lType, CastExpr::CK_NullToMemberPointer); 5281 return ResultTy; 5282 } 5283 if (LHSIsNull && 5284 (rType->isPointerType() || 5285 (!isRelational && rType->isMemberPointerType()))) { 5286 ImpCastExprToType(lex, rType, CastExpr::CK_NullToMemberPointer); 5287 return ResultTy; 5288 } 5289 5290 // Comparison of member pointers. 5291 if (!isRelational && 5292 lType->isMemberPointerType() && rType->isMemberPointerType()) { 5293 // C++ [expr.eq]p2: 5294 // In addition, pointers to members can be compared, or a pointer to 5295 // member and a null pointer constant. Pointer to member conversions 5296 // (4.11) and qualification conversions (4.4) are performed to bring 5297 // them to a common type. If one operand is a null pointer constant, 5298 // the common type is the type of the other operand. Otherwise, the 5299 // common type is a pointer to member type similar (4.4) to the type 5300 // of one of the operands, with a cv-qualification signature (4.4) 5301 // that is the union of the cv-qualification signatures of the operand 5302 // types. 5303 QualType T = FindCompositePointerType(lex, rex); 5304 if (T.isNull()) { 5305 Diag(Loc, diag::err_typecheck_comparison_of_distinct_pointers) 5306 << lType << rType << lex->getSourceRange() << rex->getSourceRange(); 5307 return QualType(); 5308 } 5309 5310 ImpCastExprToType(lex, T, CastExpr::CK_BitCast); 5311 ImpCastExprToType(rex, T, CastExpr::CK_BitCast); 5312 return ResultTy; 5313 } 5314 5315 // Comparison of nullptr_t with itself. 5316 if (lType->isNullPtrType() && rType->isNullPtrType()) 5317 return ResultTy; 5318 } 5319 5320 // Handle block pointer types. 5321 if (!isRelational && lType->isBlockPointerType() && rType->isBlockPointerType()) { 5322 QualType lpointee = lType->getAs<BlockPointerType>()->getPointeeType(); 5323 QualType rpointee = rType->getAs<BlockPointerType>()->getPointeeType(); 5324 5325 if (!LHSIsNull && !RHSIsNull && 5326 !Context.typesAreCompatible(lpointee, rpointee)) { 5327 Diag(Loc, diag::err_typecheck_comparison_of_distinct_blocks) 5328 << lType << rType << lex->getSourceRange() << rex->getSourceRange(); 5329 } 5330 ImpCastExprToType(rex, lType, CastExpr::CK_BitCast); 5331 return ResultTy; 5332 } 5333 // Allow block pointers to be compared with null pointer constants. 5334 if (!isRelational 5335 && ((lType->isBlockPointerType() && rType->isPointerType()) 5336 || (lType->isPointerType() && rType->isBlockPointerType()))) { 5337 if (!LHSIsNull && !RHSIsNull) { 5338 if (!((rType->isPointerType() && rType->getAs<PointerType>() 5339 ->getPointeeType()->isVoidType()) 5340 || (lType->isPointerType() && lType->getAs<PointerType>() 5341 ->getPointeeType()->isVoidType()))) 5342 Diag(Loc, diag::err_typecheck_comparison_of_distinct_blocks) 5343 << lType << rType << lex->getSourceRange() << rex->getSourceRange(); 5344 } 5345 ImpCastExprToType(rex, lType, CastExpr::CK_BitCast); 5346 return ResultTy; 5347 } 5348 5349 if ((lType->isObjCObjectPointerType() || rType->isObjCObjectPointerType())) { 5350 if (lType->isPointerType() || rType->isPointerType()) { 5351 const PointerType *LPT = lType->getAs<PointerType>(); 5352 const PointerType *RPT = rType->getAs<PointerType>(); 5353 bool LPtrToVoid = LPT ? 5354 Context.getCanonicalType(LPT->getPointeeType())->isVoidType() : false; 5355 bool RPtrToVoid = RPT ? 5356 Context.getCanonicalType(RPT->getPointeeType())->isVoidType() : false; 5357 5358 if (!LPtrToVoid && !RPtrToVoid && 5359 !Context.typesAreCompatible(lType, rType)) { 5360 Diag(Loc, diag::ext_typecheck_comparison_of_distinct_pointers) 5361 << lType << rType << lex->getSourceRange() << rex->getSourceRange(); 5362 } 5363 ImpCastExprToType(rex, lType, CastExpr::CK_BitCast); 5364 return ResultTy; 5365 } 5366 if (lType->isObjCObjectPointerType() && rType->isObjCObjectPointerType()) { 5367 if (!Context.areComparableObjCPointerTypes(lType, rType)) 5368 Diag(Loc, diag::ext_typecheck_comparison_of_distinct_pointers) 5369 << lType << rType << lex->getSourceRange() << rex->getSourceRange(); 5370 ImpCastExprToType(rex, lType, CastExpr::CK_BitCast); 5371 return ResultTy; 5372 } 5373 } 5374 if (lType->isAnyPointerType() && rType->isIntegerType()) { 5375 unsigned DiagID = 0; 5376 if (RHSIsNull) { 5377 if (isRelational) 5378 DiagID = diag::ext_typecheck_ordered_comparison_of_pointer_and_zero; 5379 } else if (isRelational) 5380 DiagID = diag::ext_typecheck_ordered_comparison_of_pointer_integer; 5381 else 5382 DiagID = diag::ext_typecheck_comparison_of_pointer_integer; 5383 5384 if (DiagID) { 5385 Diag(Loc, DiagID) 5386 << lType << rType << lex->getSourceRange() << rex->getSourceRange(); 5387 } 5388 ImpCastExprToType(rex, lType, CastExpr::CK_IntegralToPointer); 5389 return ResultTy; 5390 } 5391 if (lType->isIntegerType() && rType->isAnyPointerType()) { 5392 unsigned DiagID = 0; 5393 if (LHSIsNull) { 5394 if (isRelational) 5395 DiagID = diag::ext_typecheck_ordered_comparison_of_pointer_and_zero; 5396 } else if (isRelational) 5397 DiagID = diag::ext_typecheck_ordered_comparison_of_pointer_integer; 5398 else 5399 DiagID = diag::ext_typecheck_comparison_of_pointer_integer; 5400 5401 if (DiagID) { 5402 Diag(Loc, DiagID) 5403 << lType << rType << lex->getSourceRange() << rex->getSourceRange(); 5404 } 5405 ImpCastExprToType(lex, rType, CastExpr::CK_IntegralToPointer); 5406 return ResultTy; 5407 } 5408 // Handle block pointers. 5409 if (!isRelational && RHSIsNull 5410 && lType->isBlockPointerType() && rType->isIntegerType()) { 5411 ImpCastExprToType(rex, lType, CastExpr::CK_IntegralToPointer); 5412 return ResultTy; 5413 } 5414 if (!isRelational && LHSIsNull 5415 && lType->isIntegerType() && rType->isBlockPointerType()) { 5416 ImpCastExprToType(lex, rType, CastExpr::CK_IntegralToPointer); 5417 return ResultTy; 5418 } 5419 return InvalidOperands(Loc, lex, rex); 5420} 5421 5422/// CheckVectorCompareOperands - vector comparisons are a clang extension that 5423/// operates on extended vector types. Instead of producing an IntTy result, 5424/// like a scalar comparison, a vector comparison produces a vector of integer 5425/// types. 5426QualType Sema::CheckVectorCompareOperands(Expr *&lex, Expr *&rex, 5427 SourceLocation Loc, 5428 bool isRelational) { 5429 // Check to make sure we're operating on vectors of the same type and width, 5430 // Allowing one side to be a scalar of element type. 5431 QualType vType = CheckVectorOperands(Loc, lex, rex); 5432 if (vType.isNull()) 5433 return vType; 5434 5435 QualType lType = lex->getType(); 5436 QualType rType = rex->getType(); 5437 5438 // For non-floating point types, check for self-comparisons of the form 5439 // x == x, x != x, x < x, etc. These always evaluate to a constant, and 5440 // often indicate logic errors in the program. 5441 if (!lType->isFloatingType()) { 5442 if (DeclRefExpr* DRL = dyn_cast<DeclRefExpr>(lex->IgnoreParens())) 5443 if (DeclRefExpr* DRR = dyn_cast<DeclRefExpr>(rex->IgnoreParens())) 5444 if (DRL->getDecl() == DRR->getDecl()) 5445 Diag(Loc, diag::warn_selfcomparison); 5446 } 5447 5448 // Check for comparisons of floating point operands using != and ==. 5449 if (!isRelational && lType->isFloatingType()) { 5450 assert (rType->isFloatingType()); 5451 CheckFloatComparison(Loc,lex,rex); 5452 } 5453 5454 // Return the type for the comparison, which is the same as vector type for 5455 // integer vectors, or an integer type of identical size and number of 5456 // elements for floating point vectors. 5457 if (lType->isIntegerType()) 5458 return lType; 5459 5460 const VectorType *VTy = lType->getAs<VectorType>(); 5461 unsigned TypeSize = Context.getTypeSize(VTy->getElementType()); 5462 if (TypeSize == Context.getTypeSize(Context.IntTy)) 5463 return Context.getExtVectorType(Context.IntTy, VTy->getNumElements()); 5464 if (TypeSize == Context.getTypeSize(Context.LongTy)) 5465 return Context.getExtVectorType(Context.LongTy, VTy->getNumElements()); 5466 5467 assert(TypeSize == Context.getTypeSize(Context.LongLongTy) && 5468 "Unhandled vector element size in vector compare"); 5469 return Context.getExtVectorType(Context.LongLongTy, VTy->getNumElements()); 5470} 5471 5472inline QualType Sema::CheckBitwiseOperands( 5473 Expr *&lex, Expr *&rex, SourceLocation Loc, bool isCompAssign) { 5474 if (lex->getType()->isVectorType() || rex->getType()->isVectorType()) 5475 return CheckVectorOperands(Loc, lex, rex); 5476 5477 QualType compType = UsualArithmeticConversions(lex, rex, isCompAssign); 5478 5479 if (lex->getType()->isIntegerType() && rex->getType()->isIntegerType()) 5480 return compType; 5481 return InvalidOperands(Loc, lex, rex); 5482} 5483 5484inline QualType Sema::CheckLogicalOperands( // C99 6.5.[13,14] 5485 Expr *&lex, Expr *&rex, SourceLocation Loc) { 5486 if (!Context.getLangOptions().CPlusPlus) { 5487 UsualUnaryConversions(lex); 5488 UsualUnaryConversions(rex); 5489 5490 if (!lex->getType()->isScalarType() || !rex->getType()->isScalarType()) 5491 return InvalidOperands(Loc, lex, rex); 5492 5493 return Context.IntTy; 5494 } 5495 5496 // C++ [expr.log.and]p1 5497 // C++ [expr.log.or]p1 5498 // The operands are both implicitly converted to type bool (clause 4). 5499 StandardConversionSequence LHS; 5500 if (!IsStandardConversion(lex, Context.BoolTy, 5501 /*InOverloadResolution=*/false, LHS)) 5502 return InvalidOperands(Loc, lex, rex); 5503 5504 if (PerformImplicitConversion(lex, Context.BoolTy, LHS, 5505 "passing", /*IgnoreBaseAccess=*/false)) 5506 return InvalidOperands(Loc, lex, rex); 5507 5508 StandardConversionSequence RHS; 5509 if (!IsStandardConversion(rex, Context.BoolTy, 5510 /*InOverloadResolution=*/false, RHS)) 5511 return InvalidOperands(Loc, lex, rex); 5512 5513 if (PerformImplicitConversion(rex, Context.BoolTy, RHS, 5514 "passing", /*IgnoreBaseAccess=*/false)) 5515 return InvalidOperands(Loc, lex, rex); 5516 5517 // C++ [expr.log.and]p2 5518 // C++ [expr.log.or]p2 5519 // The result is a bool. 5520 return Context.BoolTy; 5521} 5522 5523/// IsReadonlyProperty - Verify that otherwise a valid l-value expression 5524/// is a read-only property; return true if so. A readonly property expression 5525/// depends on various declarations and thus must be treated specially. 5526/// 5527static bool IsReadonlyProperty(Expr *E, Sema &S) { 5528 if (E->getStmtClass() == Expr::ObjCPropertyRefExprClass) { 5529 const ObjCPropertyRefExpr* PropExpr = cast<ObjCPropertyRefExpr>(E); 5530 if (ObjCPropertyDecl *PDecl = PropExpr->getProperty()) { 5531 QualType BaseType = PropExpr->getBase()->getType(); 5532 if (const ObjCObjectPointerType *OPT = 5533 BaseType->getAsObjCInterfacePointerType()) 5534 if (ObjCInterfaceDecl *IFace = OPT->getInterfaceDecl()) 5535 if (S.isPropertyReadonly(PDecl, IFace)) 5536 return true; 5537 } 5538 } 5539 return false; 5540} 5541 5542/// CheckForModifiableLvalue - Verify that E is a modifiable lvalue. If not, 5543/// emit an error and return true. If so, return false. 5544static bool CheckForModifiableLvalue(Expr *E, SourceLocation Loc, Sema &S) { 5545 SourceLocation OrigLoc = Loc; 5546 Expr::isModifiableLvalueResult IsLV = E->isModifiableLvalue(S.Context, 5547 &Loc); 5548 if (IsLV == Expr::MLV_Valid && IsReadonlyProperty(E, S)) 5549 IsLV = Expr::MLV_ReadonlyProperty; 5550 if (IsLV == Expr::MLV_Valid) 5551 return false; 5552 5553 unsigned Diag = 0; 5554 bool NeedType = false; 5555 switch (IsLV) { // C99 6.5.16p2 5556 default: assert(0 && "Unknown result from isModifiableLvalue!"); 5557 case Expr::MLV_ConstQualified: Diag = diag::err_typecheck_assign_const; break; 5558 case Expr::MLV_ArrayType: 5559 Diag = diag::err_typecheck_array_not_modifiable_lvalue; 5560 NeedType = true; 5561 break; 5562 case Expr::MLV_NotObjectType: 5563 Diag = diag::err_typecheck_non_object_not_modifiable_lvalue; 5564 NeedType = true; 5565 break; 5566 case Expr::MLV_LValueCast: 5567 Diag = diag::err_typecheck_lvalue_casts_not_supported; 5568 break; 5569 case Expr::MLV_InvalidExpression: 5570 Diag = diag::err_typecheck_expression_not_modifiable_lvalue; 5571 break; 5572 case Expr::MLV_IncompleteType: 5573 case Expr::MLV_IncompleteVoidType: 5574 return S.RequireCompleteType(Loc, E->getType(), 5575 PDiag(diag::err_typecheck_incomplete_type_not_modifiable_lvalue) 5576 << E->getSourceRange()); 5577 case Expr::MLV_DuplicateVectorComponents: 5578 Diag = diag::err_typecheck_duplicate_vector_components_not_mlvalue; 5579 break; 5580 case Expr::MLV_NotBlockQualified: 5581 Diag = diag::err_block_decl_ref_not_modifiable_lvalue; 5582 break; 5583 case Expr::MLV_ReadonlyProperty: 5584 Diag = diag::error_readonly_property_assignment; 5585 break; 5586 case Expr::MLV_NoSetterProperty: 5587 Diag = diag::error_nosetter_property_assignment; 5588 break; 5589 } 5590 5591 SourceRange Assign; 5592 if (Loc != OrigLoc) 5593 Assign = SourceRange(OrigLoc, OrigLoc); 5594 if (NeedType) 5595 S.Diag(Loc, Diag) << E->getType() << E->getSourceRange() << Assign; 5596 else 5597 S.Diag(Loc, Diag) << E->getSourceRange() << Assign; 5598 return true; 5599} 5600 5601 5602 5603// C99 6.5.16.1 5604QualType Sema::CheckAssignmentOperands(Expr *LHS, Expr *&RHS, 5605 SourceLocation Loc, 5606 QualType CompoundType) { 5607 // Verify that LHS is a modifiable lvalue, and emit error if not. 5608 if (CheckForModifiableLvalue(LHS, Loc, *this)) 5609 return QualType(); 5610 5611 QualType LHSType = LHS->getType(); 5612 QualType RHSType = CompoundType.isNull() ? RHS->getType() : CompoundType; 5613 5614 AssignConvertType ConvTy; 5615 if (CompoundType.isNull()) { 5616 // Simple assignment "x = y". 5617 ConvTy = CheckSingleAssignmentConstraints(LHSType, RHS); 5618 // Special case of NSObject attributes on c-style pointer types. 5619 if (ConvTy == IncompatiblePointer && 5620 ((Context.isObjCNSObjectType(LHSType) && 5621 RHSType->isObjCObjectPointerType()) || 5622 (Context.isObjCNSObjectType(RHSType) && 5623 LHSType->isObjCObjectPointerType()))) 5624 ConvTy = Compatible; 5625 5626 // If the RHS is a unary plus or minus, check to see if they = and + are 5627 // right next to each other. If so, the user may have typo'd "x =+ 4" 5628 // instead of "x += 4". 5629 Expr *RHSCheck = RHS; 5630 if (ImplicitCastExpr *ICE = dyn_cast<ImplicitCastExpr>(RHSCheck)) 5631 RHSCheck = ICE->getSubExpr(); 5632 if (UnaryOperator *UO = dyn_cast<UnaryOperator>(RHSCheck)) { 5633 if ((UO->getOpcode() == UnaryOperator::Plus || 5634 UO->getOpcode() == UnaryOperator::Minus) && 5635 Loc.isFileID() && UO->getOperatorLoc().isFileID() && 5636 // Only if the two operators are exactly adjacent. 5637 Loc.getFileLocWithOffset(1) == UO->getOperatorLoc() && 5638 // And there is a space or other character before the subexpr of the 5639 // unary +/-. We don't want to warn on "x=-1". 5640 Loc.getFileLocWithOffset(2) != UO->getSubExpr()->getLocStart() && 5641 UO->getSubExpr()->getLocStart().isFileID()) { 5642 Diag(Loc, diag::warn_not_compound_assign) 5643 << (UO->getOpcode() == UnaryOperator::Plus ? "+" : "-") 5644 << SourceRange(UO->getOperatorLoc(), UO->getOperatorLoc()); 5645 } 5646 } 5647 } else { 5648 // Compound assignment "x += y" 5649 ConvTy = CheckAssignmentConstraints(LHSType, RHSType); 5650 } 5651 5652 if (DiagnoseAssignmentResult(ConvTy, Loc, LHSType, RHSType, 5653 RHS, "assigning")) 5654 return QualType(); 5655 5656 // C99 6.5.16p3: The type of an assignment expression is the type of the 5657 // left operand unless the left operand has qualified type, in which case 5658 // it is the unqualified version of the type of the left operand. 5659 // C99 6.5.16.1p2: In simple assignment, the value of the right operand 5660 // is converted to the type of the assignment expression (above). 5661 // C++ 5.17p1: the type of the assignment expression is that of its left 5662 // operand. 5663 return LHSType.getUnqualifiedType(); 5664} 5665 5666// C99 6.5.17 5667QualType Sema::CheckCommaOperands(Expr *LHS, Expr *&RHS, SourceLocation Loc) { 5668 // Comma performs lvalue conversion (C99 6.3.2.1), but not unary conversions. 5669 DefaultFunctionArrayConversion(RHS); 5670 5671 // FIXME: Check that RHS type is complete in C mode (it's legal for it to be 5672 // incomplete in C++). 5673 5674 return RHS->getType(); 5675} 5676 5677/// CheckIncrementDecrementOperand - unlike most "Check" methods, this routine 5678/// doesn't need to call UsualUnaryConversions or UsualArithmeticConversions. 5679QualType Sema::CheckIncrementDecrementOperand(Expr *Op, SourceLocation OpLoc, 5680 bool isInc) { 5681 if (Op->isTypeDependent()) 5682 return Context.DependentTy; 5683 5684 QualType ResType = Op->getType(); 5685 assert(!ResType.isNull() && "no type for increment/decrement expression"); 5686 5687 if (getLangOptions().CPlusPlus && ResType->isBooleanType()) { 5688 // Decrement of bool is not allowed. 5689 if (!isInc) { 5690 Diag(OpLoc, diag::err_decrement_bool) << Op->getSourceRange(); 5691 return QualType(); 5692 } 5693 // Increment of bool sets it to true, but is deprecated. 5694 Diag(OpLoc, diag::warn_increment_bool) << Op->getSourceRange(); 5695 } else if (ResType->isRealType()) { 5696 // OK! 5697 } else if (ResType->isAnyPointerType()) { 5698 QualType PointeeTy = ResType->getPointeeType(); 5699 5700 // C99 6.5.2.4p2, 6.5.6p2 5701 if (PointeeTy->isVoidType()) { 5702 if (getLangOptions().CPlusPlus) { 5703 Diag(OpLoc, diag::err_typecheck_pointer_arith_void_type) 5704 << Op->getSourceRange(); 5705 return QualType(); 5706 } 5707 5708 // Pointer to void is a GNU extension in C. 5709 Diag(OpLoc, diag::ext_gnu_void_ptr) << Op->getSourceRange(); 5710 } else if (PointeeTy->isFunctionType()) { 5711 if (getLangOptions().CPlusPlus) { 5712 Diag(OpLoc, diag::err_typecheck_pointer_arith_function_type) 5713 << Op->getType() << Op->getSourceRange(); 5714 return QualType(); 5715 } 5716 5717 Diag(OpLoc, diag::ext_gnu_ptr_func_arith) 5718 << ResType << Op->getSourceRange(); 5719 } else if (RequireCompleteType(OpLoc, PointeeTy, 5720 PDiag(diag::err_typecheck_arithmetic_incomplete_type) 5721 << Op->getSourceRange() 5722 << ResType)) 5723 return QualType(); 5724 // Diagnose bad cases where we step over interface counts. 5725 else if (PointeeTy->isObjCInterfaceType() && LangOpts.ObjCNonFragileABI) { 5726 Diag(OpLoc, diag::err_arithmetic_nonfragile_interface) 5727 << PointeeTy << Op->getSourceRange(); 5728 return QualType(); 5729 } 5730 } else if (ResType->isComplexType()) { 5731 // C99 does not support ++/-- on complex types, we allow as an extension. 5732 Diag(OpLoc, diag::ext_integer_increment_complex) 5733 << ResType << Op->getSourceRange(); 5734 } else { 5735 Diag(OpLoc, diag::err_typecheck_illegal_increment_decrement) 5736 << ResType << int(isInc) << Op->getSourceRange(); 5737 return QualType(); 5738 } 5739 // At this point, we know we have a real, complex or pointer type. 5740 // Now make sure the operand is a modifiable lvalue. 5741 if (CheckForModifiableLvalue(Op, OpLoc, *this)) 5742 return QualType(); 5743 return ResType; 5744} 5745 5746/// getPrimaryDecl - Helper function for CheckAddressOfOperand(). 5747/// This routine allows us to typecheck complex/recursive expressions 5748/// where the declaration is needed for type checking. We only need to 5749/// handle cases when the expression references a function designator 5750/// or is an lvalue. Here are some examples: 5751/// - &(x) => x 5752/// - &*****f => f for f a function designator. 5753/// - &s.xx => s 5754/// - &s.zz[1].yy -> s, if zz is an array 5755/// - *(x + 1) -> x, if x is an array 5756/// - &"123"[2] -> 0 5757/// - & __real__ x -> x 5758static NamedDecl *getPrimaryDecl(Expr *E) { 5759 switch (E->getStmtClass()) { 5760 case Stmt::DeclRefExprClass: 5761 return cast<DeclRefExpr>(E)->getDecl(); 5762 case Stmt::MemberExprClass: 5763 // If this is an arrow operator, the address is an offset from 5764 // the base's value, so the object the base refers to is 5765 // irrelevant. 5766 if (cast<MemberExpr>(E)->isArrow()) 5767 return 0; 5768 // Otherwise, the expression refers to a part of the base 5769 return getPrimaryDecl(cast<MemberExpr>(E)->getBase()); 5770 case Stmt::ArraySubscriptExprClass: { 5771 // FIXME: This code shouldn't be necessary! We should catch the implicit 5772 // promotion of register arrays earlier. 5773 Expr* Base = cast<ArraySubscriptExpr>(E)->getBase(); 5774 if (ImplicitCastExpr* ICE = dyn_cast<ImplicitCastExpr>(Base)) { 5775 if (ICE->getSubExpr()->getType()->isArrayType()) 5776 return getPrimaryDecl(ICE->getSubExpr()); 5777 } 5778 return 0; 5779 } 5780 case Stmt::UnaryOperatorClass: { 5781 UnaryOperator *UO = cast<UnaryOperator>(E); 5782 5783 switch(UO->getOpcode()) { 5784 case UnaryOperator::Real: 5785 case UnaryOperator::Imag: 5786 case UnaryOperator::Extension: 5787 return getPrimaryDecl(UO->getSubExpr()); 5788 default: 5789 return 0; 5790 } 5791 } 5792 case Stmt::ParenExprClass: 5793 return getPrimaryDecl(cast<ParenExpr>(E)->getSubExpr()); 5794 case Stmt::ImplicitCastExprClass: 5795 // If the result of an implicit cast is an l-value, we care about 5796 // the sub-expression; otherwise, the result here doesn't matter. 5797 return getPrimaryDecl(cast<ImplicitCastExpr>(E)->getSubExpr()); 5798 default: 5799 return 0; 5800 } 5801} 5802 5803/// CheckAddressOfOperand - The operand of & must be either a function 5804/// designator or an lvalue designating an object. If it is an lvalue, the 5805/// object cannot be declared with storage class register or be a bit field. 5806/// Note: The usual conversions are *not* applied to the operand of the & 5807/// operator (C99 6.3.2.1p[2-4]), and its result is never an lvalue. 5808/// In C++, the operand might be an overloaded function name, in which case 5809/// we allow the '&' but retain the overloaded-function type. 5810QualType Sema::CheckAddressOfOperand(Expr *op, SourceLocation OpLoc) { 5811 // Make sure to ignore parentheses in subsequent checks 5812 op = op->IgnoreParens(); 5813 5814 if (op->isTypeDependent()) 5815 return Context.DependentTy; 5816 5817 if (getLangOptions().C99) { 5818 // Implement C99-only parts of addressof rules. 5819 if (UnaryOperator* uOp = dyn_cast<UnaryOperator>(op)) { 5820 if (uOp->getOpcode() == UnaryOperator::Deref) 5821 // Per C99 6.5.3.2, the address of a deref always returns a valid result 5822 // (assuming the deref expression is valid). 5823 return uOp->getSubExpr()->getType(); 5824 } 5825 // Technically, there should be a check for array subscript 5826 // expressions here, but the result of one is always an lvalue anyway. 5827 } 5828 NamedDecl *dcl = getPrimaryDecl(op); 5829 Expr::isLvalueResult lval = op->isLvalue(Context); 5830 5831 if (lval != Expr::LV_Valid && lval != Expr::LV_IncompleteVoidType) { 5832 // C99 6.5.3.2p1 5833 // The operand must be either an l-value or a function designator 5834 if (!op->getType()->isFunctionType()) { 5835 // FIXME: emit more specific diag... 5836 Diag(OpLoc, diag::err_typecheck_invalid_lvalue_addrof) 5837 << op->getSourceRange(); 5838 return QualType(); 5839 } 5840 } else if (op->getBitField()) { // C99 6.5.3.2p1 5841 // The operand cannot be a bit-field 5842 Diag(OpLoc, diag::err_typecheck_address_of) 5843 << "bit-field" << op->getSourceRange(); 5844 return QualType(); 5845 } else if (isa<ExtVectorElementExpr>(op) || (isa<ArraySubscriptExpr>(op) && 5846 cast<ArraySubscriptExpr>(op)->getBase()->getType()->isVectorType())){ 5847 // The operand cannot be an element of a vector 5848 Diag(OpLoc, diag::err_typecheck_address_of) 5849 << "vector element" << op->getSourceRange(); 5850 return QualType(); 5851 } else if (isa<ObjCPropertyRefExpr>(op)) { 5852 // cannot take address of a property expression. 5853 Diag(OpLoc, diag::err_typecheck_address_of) 5854 << "property expression" << op->getSourceRange(); 5855 return QualType(); 5856 } else if (ConditionalOperator *CO = dyn_cast<ConditionalOperator>(op)) { 5857 // FIXME: Can LHS ever be null here? 5858 if (!CheckAddressOfOperand(CO->getTrueExpr(), OpLoc).isNull()) 5859 return CheckAddressOfOperand(CO->getFalseExpr(), OpLoc); 5860 } else if (isa<UnresolvedLookupExpr>(op)) { 5861 return Context.OverloadTy; 5862 } else if (dcl) { // C99 6.5.3.2p1 5863 // We have an lvalue with a decl. Make sure the decl is not declared 5864 // with the register storage-class specifier. 5865 if (const VarDecl *vd = dyn_cast<VarDecl>(dcl)) { 5866 if (vd->getStorageClass() == VarDecl::Register) { 5867 Diag(OpLoc, diag::err_typecheck_address_of) 5868 << "register variable" << op->getSourceRange(); 5869 return QualType(); 5870 } 5871 } else if (isa<FunctionTemplateDecl>(dcl)) { 5872 return Context.OverloadTy; 5873 } else if (FieldDecl *FD = dyn_cast<FieldDecl>(dcl)) { 5874 // Okay: we can take the address of a field. 5875 // Could be a pointer to member, though, if there is an explicit 5876 // scope qualifier for the class. 5877 if (isa<DeclRefExpr>(op) && cast<DeclRefExpr>(op)->getQualifier()) { 5878 DeclContext *Ctx = dcl->getDeclContext(); 5879 if (Ctx && Ctx->isRecord()) { 5880 if (FD->getType()->isReferenceType()) { 5881 Diag(OpLoc, 5882 diag::err_cannot_form_pointer_to_member_of_reference_type) 5883 << FD->getDeclName() << FD->getType(); 5884 return QualType(); 5885 } 5886 5887 return Context.getMemberPointerType(op->getType(), 5888 Context.getTypeDeclType(cast<RecordDecl>(Ctx)).getTypePtr()); 5889 } 5890 } 5891 } else if (CXXMethodDecl *MD = dyn_cast<CXXMethodDecl>(dcl)) { 5892 // Okay: we can take the address of a function. 5893 // As above. 5894 if (isa<DeclRefExpr>(op) && cast<DeclRefExpr>(op)->getQualifier() && 5895 MD->isInstance()) 5896 return Context.getMemberPointerType(op->getType(), 5897 Context.getTypeDeclType(MD->getParent()).getTypePtr()); 5898 } else if (!isa<FunctionDecl>(dcl)) 5899 assert(0 && "Unknown/unexpected decl type"); 5900 } 5901 5902 if (lval == Expr::LV_IncompleteVoidType) { 5903 // Taking the address of a void variable is technically illegal, but we 5904 // allow it in cases which are otherwise valid. 5905 // Example: "extern void x; void* y = &x;". 5906 Diag(OpLoc, diag::ext_typecheck_addrof_void) << op->getSourceRange(); 5907 } 5908 5909 // If the operand has type "type", the result has type "pointer to type". 5910 return Context.getPointerType(op->getType()); 5911} 5912 5913QualType Sema::CheckIndirectionOperand(Expr *Op, SourceLocation OpLoc) { 5914 if (Op->isTypeDependent()) 5915 return Context.DependentTy; 5916 5917 UsualUnaryConversions(Op); 5918 QualType Ty = Op->getType(); 5919 5920 // Note that per both C89 and C99, this is always legal, even if ptype is an 5921 // incomplete type or void. It would be possible to warn about dereferencing 5922 // a void pointer, but it's completely well-defined, and such a warning is 5923 // unlikely to catch any mistakes. 5924 if (const PointerType *PT = Ty->getAs<PointerType>()) 5925 return PT->getPointeeType(); 5926 5927 if (const ObjCObjectPointerType *OPT = Ty->getAs<ObjCObjectPointerType>()) 5928 return OPT->getPointeeType(); 5929 5930 Diag(OpLoc, diag::err_typecheck_indirection_requires_pointer) 5931 << Ty << Op->getSourceRange(); 5932 return QualType(); 5933} 5934 5935static inline BinaryOperator::Opcode ConvertTokenKindToBinaryOpcode( 5936 tok::TokenKind Kind) { 5937 BinaryOperator::Opcode Opc; 5938 switch (Kind) { 5939 default: assert(0 && "Unknown binop!"); 5940 case tok::periodstar: Opc = BinaryOperator::PtrMemD; break; 5941 case tok::arrowstar: Opc = BinaryOperator::PtrMemI; break; 5942 case tok::star: Opc = BinaryOperator::Mul; break; 5943 case tok::slash: Opc = BinaryOperator::Div; break; 5944 case tok::percent: Opc = BinaryOperator::Rem; break; 5945 case tok::plus: Opc = BinaryOperator::Add; break; 5946 case tok::minus: Opc = BinaryOperator::Sub; break; 5947 case tok::lessless: Opc = BinaryOperator::Shl; break; 5948 case tok::greatergreater: Opc = BinaryOperator::Shr; break; 5949 case tok::lessequal: Opc = BinaryOperator::LE; break; 5950 case tok::less: Opc = BinaryOperator::LT; break; 5951 case tok::greaterequal: Opc = BinaryOperator::GE; break; 5952 case tok::greater: Opc = BinaryOperator::GT; break; 5953 case tok::exclaimequal: Opc = BinaryOperator::NE; break; 5954 case tok::equalequal: Opc = BinaryOperator::EQ; break; 5955 case tok::amp: Opc = BinaryOperator::And; break; 5956 case tok::caret: Opc = BinaryOperator::Xor; break; 5957 case tok::pipe: Opc = BinaryOperator::Or; break; 5958 case tok::ampamp: Opc = BinaryOperator::LAnd; break; 5959 case tok::pipepipe: Opc = BinaryOperator::LOr; break; 5960 case tok::equal: Opc = BinaryOperator::Assign; break; 5961 case tok::starequal: Opc = BinaryOperator::MulAssign; break; 5962 case tok::slashequal: Opc = BinaryOperator::DivAssign; break; 5963 case tok::percentequal: Opc = BinaryOperator::RemAssign; break; 5964 case tok::plusequal: Opc = BinaryOperator::AddAssign; break; 5965 case tok::minusequal: Opc = BinaryOperator::SubAssign; break; 5966 case tok::lesslessequal: Opc = BinaryOperator::ShlAssign; break; 5967 case tok::greatergreaterequal: Opc = BinaryOperator::ShrAssign; break; 5968 case tok::ampequal: Opc = BinaryOperator::AndAssign; break; 5969 case tok::caretequal: Opc = BinaryOperator::XorAssign; break; 5970 case tok::pipeequal: Opc = BinaryOperator::OrAssign; break; 5971 case tok::comma: Opc = BinaryOperator::Comma; break; 5972 } 5973 return Opc; 5974} 5975 5976static inline UnaryOperator::Opcode ConvertTokenKindToUnaryOpcode( 5977 tok::TokenKind Kind) { 5978 UnaryOperator::Opcode Opc; 5979 switch (Kind) { 5980 default: assert(0 && "Unknown unary op!"); 5981 case tok::plusplus: Opc = UnaryOperator::PreInc; break; 5982 case tok::minusminus: Opc = UnaryOperator::PreDec; break; 5983 case tok::amp: Opc = UnaryOperator::AddrOf; break; 5984 case tok::star: Opc = UnaryOperator::Deref; break; 5985 case tok::plus: Opc = UnaryOperator::Plus; break; 5986 case tok::minus: Opc = UnaryOperator::Minus; break; 5987 case tok::tilde: Opc = UnaryOperator::Not; break; 5988 case tok::exclaim: Opc = UnaryOperator::LNot; break; 5989 case tok::kw___real: Opc = UnaryOperator::Real; break; 5990 case tok::kw___imag: Opc = UnaryOperator::Imag; break; 5991 case tok::kw___extension__: Opc = UnaryOperator::Extension; break; 5992 } 5993 return Opc; 5994} 5995 5996/// CreateBuiltinBinOp - Creates a new built-in binary operation with 5997/// operator @p Opc at location @c TokLoc. This routine only supports 5998/// built-in operations; ActOnBinOp handles overloaded operators. 5999Action::OwningExprResult Sema::CreateBuiltinBinOp(SourceLocation OpLoc, 6000 unsigned Op, 6001 Expr *lhs, Expr *rhs) { 6002 QualType ResultTy; // Result type of the binary operator. 6003 BinaryOperator::Opcode Opc = (BinaryOperator::Opcode)Op; 6004 // The following two variables are used for compound assignment operators 6005 QualType CompLHSTy; // Type of LHS after promotions for computation 6006 QualType CompResultTy; // Type of computation result 6007 6008 switch (Opc) { 6009 case BinaryOperator::Assign: 6010 ResultTy = CheckAssignmentOperands(lhs, rhs, OpLoc, QualType()); 6011 break; 6012 case BinaryOperator::PtrMemD: 6013 case BinaryOperator::PtrMemI: 6014 ResultTy = CheckPointerToMemberOperands(lhs, rhs, OpLoc, 6015 Opc == BinaryOperator::PtrMemI); 6016 break; 6017 case BinaryOperator::Mul: 6018 case BinaryOperator::Div: 6019 ResultTy = CheckMultiplyDivideOperands(lhs, rhs, OpLoc); 6020 break; 6021 case BinaryOperator::Rem: 6022 ResultTy = CheckRemainderOperands(lhs, rhs, OpLoc); 6023 break; 6024 case BinaryOperator::Add: 6025 ResultTy = CheckAdditionOperands(lhs, rhs, OpLoc); 6026 break; 6027 case BinaryOperator::Sub: 6028 ResultTy = CheckSubtractionOperands(lhs, rhs, OpLoc); 6029 break; 6030 case BinaryOperator::Shl: 6031 case BinaryOperator::Shr: 6032 ResultTy = CheckShiftOperands(lhs, rhs, OpLoc); 6033 break; 6034 case BinaryOperator::LE: 6035 case BinaryOperator::LT: 6036 case BinaryOperator::GE: 6037 case BinaryOperator::GT: 6038 ResultTy = CheckCompareOperands(lhs, rhs, OpLoc, Opc, true); 6039 break; 6040 case BinaryOperator::EQ: 6041 case BinaryOperator::NE: 6042 ResultTy = CheckCompareOperands(lhs, rhs, OpLoc, Opc, false); 6043 break; 6044 case BinaryOperator::And: 6045 case BinaryOperator::Xor: 6046 case BinaryOperator::Or: 6047 ResultTy = CheckBitwiseOperands(lhs, rhs, OpLoc); 6048 break; 6049 case BinaryOperator::LAnd: 6050 case BinaryOperator::LOr: 6051 ResultTy = CheckLogicalOperands(lhs, rhs, OpLoc); 6052 break; 6053 case BinaryOperator::MulAssign: 6054 case BinaryOperator::DivAssign: 6055 CompResultTy = CheckMultiplyDivideOperands(lhs, rhs, OpLoc, true); 6056 CompLHSTy = CompResultTy; 6057 if (!CompResultTy.isNull()) 6058 ResultTy = CheckAssignmentOperands(lhs, rhs, OpLoc, CompResultTy); 6059 break; 6060 case BinaryOperator::RemAssign: 6061 CompResultTy = CheckRemainderOperands(lhs, rhs, OpLoc, true); 6062 CompLHSTy = CompResultTy; 6063 if (!CompResultTy.isNull()) 6064 ResultTy = CheckAssignmentOperands(lhs, rhs, OpLoc, CompResultTy); 6065 break; 6066 case BinaryOperator::AddAssign: 6067 CompResultTy = CheckAdditionOperands(lhs, rhs, OpLoc, &CompLHSTy); 6068 if (!CompResultTy.isNull()) 6069 ResultTy = CheckAssignmentOperands(lhs, rhs, OpLoc, CompResultTy); 6070 break; 6071 case BinaryOperator::SubAssign: 6072 CompResultTy = CheckSubtractionOperands(lhs, rhs, OpLoc, &CompLHSTy); 6073 if (!CompResultTy.isNull()) 6074 ResultTy = CheckAssignmentOperands(lhs, rhs, OpLoc, CompResultTy); 6075 break; 6076 case BinaryOperator::ShlAssign: 6077 case BinaryOperator::ShrAssign: 6078 CompResultTy = CheckShiftOperands(lhs, rhs, OpLoc, true); 6079 CompLHSTy = CompResultTy; 6080 if (!CompResultTy.isNull()) 6081 ResultTy = CheckAssignmentOperands(lhs, rhs, OpLoc, CompResultTy); 6082 break; 6083 case BinaryOperator::AndAssign: 6084 case BinaryOperator::XorAssign: 6085 case BinaryOperator::OrAssign: 6086 CompResultTy = CheckBitwiseOperands(lhs, rhs, OpLoc, true); 6087 CompLHSTy = CompResultTy; 6088 if (!CompResultTy.isNull()) 6089 ResultTy = CheckAssignmentOperands(lhs, rhs, OpLoc, CompResultTy); 6090 break; 6091 case BinaryOperator::Comma: 6092 ResultTy = CheckCommaOperands(lhs, rhs, OpLoc); 6093 break; 6094 } 6095 if (ResultTy.isNull()) 6096 return ExprError(); 6097 if (CompResultTy.isNull()) 6098 return Owned(new (Context) BinaryOperator(lhs, rhs, Opc, ResultTy, OpLoc)); 6099 else 6100 return Owned(new (Context) CompoundAssignOperator(lhs, rhs, Opc, ResultTy, 6101 CompLHSTy, CompResultTy, 6102 OpLoc)); 6103} 6104 6105/// SuggestParentheses - Emit a diagnostic together with a fixit hint that wraps 6106/// ParenRange in parentheses. 6107static void SuggestParentheses(Sema &Self, SourceLocation Loc, 6108 const PartialDiagnostic &PD, 6109 SourceRange ParenRange) 6110{ 6111 SourceLocation EndLoc = Self.PP.getLocForEndOfToken(ParenRange.getEnd()); 6112 if (!ParenRange.getEnd().isFileID() || EndLoc.isInvalid()) { 6113 // We can't display the parentheses, so just dig the 6114 // warning/error and return. 6115 Self.Diag(Loc, PD); 6116 return; 6117 } 6118 6119 Self.Diag(Loc, PD) 6120 << CodeModificationHint::CreateInsertion(ParenRange.getBegin(), "(") 6121 << CodeModificationHint::CreateInsertion(EndLoc, ")"); 6122} 6123 6124/// DiagnoseBitwisePrecedence - Emit a warning when bitwise and comparison 6125/// operators are mixed in a way that suggests that the programmer forgot that 6126/// comparison operators have higher precedence. The most typical example of 6127/// such code is "flags & 0x0020 != 0", which is equivalent to "flags & 1". 6128static void DiagnoseBitwisePrecedence(Sema &Self, BinaryOperator::Opcode Opc, 6129 SourceLocation OpLoc,Expr *lhs,Expr *rhs){ 6130 typedef BinaryOperator BinOp; 6131 BinOp::Opcode lhsopc = static_cast<BinOp::Opcode>(-1), 6132 rhsopc = static_cast<BinOp::Opcode>(-1); 6133 if (BinOp *BO = dyn_cast<BinOp>(lhs)) 6134 lhsopc = BO->getOpcode(); 6135 if (BinOp *BO = dyn_cast<BinOp>(rhs)) 6136 rhsopc = BO->getOpcode(); 6137 6138 // Subs are not binary operators. 6139 if (lhsopc == -1 && rhsopc == -1) 6140 return; 6141 6142 // Bitwise operations are sometimes used as eager logical ops. 6143 // Don't diagnose this. 6144 if ((BinOp::isComparisonOp(lhsopc) || BinOp::isBitwiseOp(lhsopc)) && 6145 (BinOp::isComparisonOp(rhsopc) || BinOp::isBitwiseOp(rhsopc))) 6146 return; 6147 6148 if (BinOp::isComparisonOp(lhsopc)) 6149 SuggestParentheses(Self, OpLoc, 6150 PDiag(diag::warn_precedence_bitwise_rel) 6151 << SourceRange(lhs->getLocStart(), OpLoc) 6152 << BinOp::getOpcodeStr(Opc) << BinOp::getOpcodeStr(lhsopc), 6153 SourceRange(cast<BinOp>(lhs)->getRHS()->getLocStart(), rhs->getLocEnd())); 6154 else if (BinOp::isComparisonOp(rhsopc)) 6155 SuggestParentheses(Self, OpLoc, 6156 PDiag(diag::warn_precedence_bitwise_rel) 6157 << SourceRange(OpLoc, rhs->getLocEnd()) 6158 << BinOp::getOpcodeStr(Opc) << BinOp::getOpcodeStr(rhsopc), 6159 SourceRange(lhs->getLocEnd(), cast<BinOp>(rhs)->getLHS()->getLocStart())); 6160} 6161 6162/// DiagnoseBinOpPrecedence - Emit warnings for expressions with tricky 6163/// precedence. This currently diagnoses only "arg1 'bitwise' arg2 'eq' arg3". 6164/// But it could also warn about arg1 && arg2 || arg3, as GCC 4.3+ does. 6165static void DiagnoseBinOpPrecedence(Sema &Self, BinaryOperator::Opcode Opc, 6166 SourceLocation OpLoc, Expr *lhs, Expr *rhs){ 6167 if (BinaryOperator::isBitwiseOp(Opc)) 6168 DiagnoseBitwisePrecedence(Self, Opc, OpLoc, lhs, rhs); 6169} 6170 6171// Binary Operators. 'Tok' is the token for the operator. 6172Action::OwningExprResult Sema::ActOnBinOp(Scope *S, SourceLocation TokLoc, 6173 tok::TokenKind Kind, 6174 ExprArg LHS, ExprArg RHS) { 6175 BinaryOperator::Opcode Opc = ConvertTokenKindToBinaryOpcode(Kind); 6176 Expr *lhs = LHS.takeAs<Expr>(), *rhs = RHS.takeAs<Expr>(); 6177 6178 assert((lhs != 0) && "ActOnBinOp(): missing left expression"); 6179 assert((rhs != 0) && "ActOnBinOp(): missing right expression"); 6180 6181 // Emit warnings for tricky precedence issues, e.g. "bitfield & 0x4 == 0" 6182 DiagnoseBinOpPrecedence(*this, Opc, TokLoc, lhs, rhs); 6183 6184 return BuildBinOp(S, TokLoc, Opc, lhs, rhs); 6185} 6186 6187Action::OwningExprResult Sema::BuildBinOp(Scope *S, SourceLocation OpLoc, 6188 BinaryOperator::Opcode Opc, 6189 Expr *lhs, Expr *rhs) { 6190 if (getLangOptions().CPlusPlus && 6191 (lhs->getType()->isOverloadableType() || 6192 rhs->getType()->isOverloadableType())) { 6193 // Find all of the overloaded operators visible from this 6194 // point. We perform both an operator-name lookup from the local 6195 // scope and an argument-dependent lookup based on the types of 6196 // the arguments. 6197 FunctionSet Functions; 6198 OverloadedOperatorKind OverOp = BinaryOperator::getOverloadedOperator(Opc); 6199 if (OverOp != OO_None) { 6200 if (S) 6201 LookupOverloadedOperatorName(OverOp, S, lhs->getType(), rhs->getType(), 6202 Functions); 6203 Expr *Args[2] = { lhs, rhs }; 6204 DeclarationName OpName 6205 = Context.DeclarationNames.getCXXOperatorName(OverOp); 6206 ArgumentDependentLookup(OpName, /*Operator*/true, Args, 2, Functions); 6207 } 6208 6209 // Build the (potentially-overloaded, potentially-dependent) 6210 // binary operation. 6211 return CreateOverloadedBinOp(OpLoc, Opc, Functions, lhs, rhs); 6212 } 6213 6214 // Build a built-in binary operation. 6215 return CreateBuiltinBinOp(OpLoc, Opc, lhs, rhs); 6216} 6217 6218Action::OwningExprResult Sema::CreateBuiltinUnaryOp(SourceLocation OpLoc, 6219 unsigned OpcIn, 6220 ExprArg InputArg) { 6221 UnaryOperator::Opcode Opc = static_cast<UnaryOperator::Opcode>(OpcIn); 6222 6223 // FIXME: Input is modified below, but InputArg is not updated appropriately. 6224 Expr *Input = (Expr *)InputArg.get(); 6225 QualType resultType; 6226 switch (Opc) { 6227 case UnaryOperator::OffsetOf: 6228 assert(false && "Invalid unary operator"); 6229 break; 6230 6231 case UnaryOperator::PreInc: 6232 case UnaryOperator::PreDec: 6233 case UnaryOperator::PostInc: 6234 case UnaryOperator::PostDec: 6235 resultType = CheckIncrementDecrementOperand(Input, OpLoc, 6236 Opc == UnaryOperator::PreInc || 6237 Opc == UnaryOperator::PostInc); 6238 break; 6239 case UnaryOperator::AddrOf: 6240 resultType = CheckAddressOfOperand(Input, OpLoc); 6241 break; 6242 case UnaryOperator::Deref: 6243 DefaultFunctionArrayConversion(Input); 6244 resultType = CheckIndirectionOperand(Input, OpLoc); 6245 break; 6246 case UnaryOperator::Plus: 6247 case UnaryOperator::Minus: 6248 UsualUnaryConversions(Input); 6249 resultType = Input->getType(); 6250 if (resultType->isDependentType()) 6251 break; 6252 if (resultType->isArithmeticType()) // C99 6.5.3.3p1 6253 break; 6254 else if (getLangOptions().CPlusPlus && // C++ [expr.unary.op]p6-7 6255 resultType->isEnumeralType()) 6256 break; 6257 else if (getLangOptions().CPlusPlus && // C++ [expr.unary.op]p6 6258 Opc == UnaryOperator::Plus && 6259 resultType->isPointerType()) 6260 break; 6261 6262 return ExprError(Diag(OpLoc, diag::err_typecheck_unary_expr) 6263 << resultType << Input->getSourceRange()); 6264 case UnaryOperator::Not: // bitwise complement 6265 UsualUnaryConversions(Input); 6266 resultType = Input->getType(); 6267 if (resultType->isDependentType()) 6268 break; 6269 // C99 6.5.3.3p1. We allow complex int and float as a GCC extension. 6270 if (resultType->isComplexType() || resultType->isComplexIntegerType()) 6271 // C99 does not support '~' for complex conjugation. 6272 Diag(OpLoc, diag::ext_integer_complement_complex) 6273 << resultType << Input->getSourceRange(); 6274 else if (!resultType->isIntegerType()) 6275 return ExprError(Diag(OpLoc, diag::err_typecheck_unary_expr) 6276 << resultType << Input->getSourceRange()); 6277 break; 6278 case UnaryOperator::LNot: // logical negation 6279 // Unlike +/-/~, integer promotions aren't done here (C99 6.5.3.3p5). 6280 DefaultFunctionArrayConversion(Input); 6281 resultType = Input->getType(); 6282 if (resultType->isDependentType()) 6283 break; 6284 if (!resultType->isScalarType()) // C99 6.5.3.3p1 6285 return ExprError(Diag(OpLoc, diag::err_typecheck_unary_expr) 6286 << resultType << Input->getSourceRange()); 6287 // LNot always has type int. C99 6.5.3.3p5. 6288 // In C++, it's bool. C++ 5.3.1p8 6289 resultType = getLangOptions().CPlusPlus ? Context.BoolTy : Context.IntTy; 6290 break; 6291 case UnaryOperator::Real: 6292 case UnaryOperator::Imag: 6293 resultType = CheckRealImagOperand(Input, OpLoc, Opc == UnaryOperator::Real); 6294 break; 6295 case UnaryOperator::Extension: 6296 resultType = Input->getType(); 6297 break; 6298 } 6299 if (resultType.isNull()) 6300 return ExprError(); 6301 6302 InputArg.release(); 6303 return Owned(new (Context) UnaryOperator(Input, Opc, resultType, OpLoc)); 6304} 6305 6306Action::OwningExprResult Sema::BuildUnaryOp(Scope *S, SourceLocation OpLoc, 6307 UnaryOperator::Opcode Opc, 6308 ExprArg input) { 6309 Expr *Input = (Expr*)input.get(); 6310 if (getLangOptions().CPlusPlus && Input->getType()->isOverloadableType() && 6311 Opc != UnaryOperator::Extension) { 6312 // Find all of the overloaded operators visible from this 6313 // point. We perform both an operator-name lookup from the local 6314 // scope and an argument-dependent lookup based on the types of 6315 // the arguments. 6316 FunctionSet Functions; 6317 OverloadedOperatorKind OverOp = UnaryOperator::getOverloadedOperator(Opc); 6318 if (OverOp != OO_None) { 6319 if (S) 6320 LookupOverloadedOperatorName(OverOp, S, Input->getType(), QualType(), 6321 Functions); 6322 DeclarationName OpName 6323 = Context.DeclarationNames.getCXXOperatorName(OverOp); 6324 ArgumentDependentLookup(OpName, /*Operator*/true, &Input, 1, Functions); 6325 } 6326 6327 return CreateOverloadedUnaryOp(OpLoc, Opc, Functions, move(input)); 6328 } 6329 6330 return CreateBuiltinUnaryOp(OpLoc, Opc, move(input)); 6331} 6332 6333// Unary Operators. 'Tok' is the token for the operator. 6334Action::OwningExprResult Sema::ActOnUnaryOp(Scope *S, SourceLocation OpLoc, 6335 tok::TokenKind Op, ExprArg input) { 6336 return BuildUnaryOp(S, OpLoc, ConvertTokenKindToUnaryOpcode(Op), move(input)); 6337} 6338 6339/// ActOnAddrLabel - Parse the GNU address of label extension: "&&foo". 6340Sema::OwningExprResult Sema::ActOnAddrLabel(SourceLocation OpLoc, 6341 SourceLocation LabLoc, 6342 IdentifierInfo *LabelII) { 6343 // Look up the record for this label identifier. 6344 LabelStmt *&LabelDecl = getLabelMap()[LabelII]; 6345 6346 // If we haven't seen this label yet, create a forward reference. It 6347 // will be validated and/or cleaned up in ActOnFinishFunctionBody. 6348 if (LabelDecl == 0) 6349 LabelDecl = new (Context) LabelStmt(LabLoc, LabelII, 0); 6350 6351 // Create the AST node. The address of a label always has type 'void*'. 6352 return Owned(new (Context) AddrLabelExpr(OpLoc, LabLoc, LabelDecl, 6353 Context.getPointerType(Context.VoidTy))); 6354} 6355 6356Sema::OwningExprResult 6357Sema::ActOnStmtExpr(SourceLocation LPLoc, StmtArg substmt, 6358 SourceLocation RPLoc) { // "({..})" 6359 Stmt *SubStmt = static_cast<Stmt*>(substmt.get()); 6360 assert(SubStmt && isa<CompoundStmt>(SubStmt) && "Invalid action invocation!"); 6361 CompoundStmt *Compound = cast<CompoundStmt>(SubStmt); 6362 6363 bool isFileScope = getCurFunctionOrMethodDecl() == 0; 6364 if (isFileScope) 6365 return ExprError(Diag(LPLoc, diag::err_stmtexpr_file_scope)); 6366 6367 // FIXME: there are a variety of strange constraints to enforce here, for 6368 // example, it is not possible to goto into a stmt expression apparently. 6369 // More semantic analysis is needed. 6370 6371 // If there are sub stmts in the compound stmt, take the type of the last one 6372 // as the type of the stmtexpr. 6373 QualType Ty = Context.VoidTy; 6374 6375 if (!Compound->body_empty()) { 6376 Stmt *LastStmt = Compound->body_back(); 6377 // If LastStmt is a label, skip down through into the body. 6378 while (LabelStmt *Label = dyn_cast<LabelStmt>(LastStmt)) 6379 LastStmt = Label->getSubStmt(); 6380 6381 if (Expr *LastExpr = dyn_cast<Expr>(LastStmt)) 6382 Ty = LastExpr->getType(); 6383 } 6384 6385 // FIXME: Check that expression type is complete/non-abstract; statement 6386 // expressions are not lvalues. 6387 6388 substmt.release(); 6389 return Owned(new (Context) StmtExpr(Compound, Ty, LPLoc, RPLoc)); 6390} 6391 6392Sema::OwningExprResult Sema::ActOnBuiltinOffsetOf(Scope *S, 6393 SourceLocation BuiltinLoc, 6394 SourceLocation TypeLoc, 6395 TypeTy *argty, 6396 OffsetOfComponent *CompPtr, 6397 unsigned NumComponents, 6398 SourceLocation RPLoc) { 6399 // FIXME: This function leaks all expressions in the offset components on 6400 // error. 6401 // FIXME: Preserve type source info. 6402 QualType ArgTy = GetTypeFromParser(argty); 6403 assert(!ArgTy.isNull() && "Missing type argument!"); 6404 6405 bool Dependent = ArgTy->isDependentType(); 6406 6407 // We must have at least one component that refers to the type, and the first 6408 // one is known to be a field designator. Verify that the ArgTy represents 6409 // a struct/union/class. 6410 if (!Dependent && !ArgTy->isRecordType()) 6411 return ExprError(Diag(TypeLoc, diag::err_offsetof_record_type) << ArgTy); 6412 6413 // FIXME: Type must be complete per C99 7.17p3 because a declaring a variable 6414 // with an incomplete type would be illegal. 6415 6416 // Otherwise, create a null pointer as the base, and iteratively process 6417 // the offsetof designators. 6418 QualType ArgTyPtr = Context.getPointerType(ArgTy); 6419 Expr* Res = new (Context) ImplicitValueInitExpr(ArgTyPtr); 6420 Res = new (Context) UnaryOperator(Res, UnaryOperator::Deref, 6421 ArgTy, SourceLocation()); 6422 6423 // offsetof with non-identifier designators (e.g. "offsetof(x, a.b[c])") are a 6424 // GCC extension, diagnose them. 6425 // FIXME: This diagnostic isn't actually visible because the location is in 6426 // a system header! 6427 if (NumComponents != 1) 6428 Diag(BuiltinLoc, diag::ext_offsetof_extended_field_designator) 6429 << SourceRange(CompPtr[1].LocStart, CompPtr[NumComponents-1].LocEnd); 6430 6431 if (!Dependent) { 6432 bool DidWarnAboutNonPOD = false; 6433 6434 if (RequireCompleteType(TypeLoc, Res->getType(), 6435 diag::err_offsetof_incomplete_type)) 6436 return ExprError(); 6437 6438 // FIXME: Dependent case loses a lot of information here. And probably 6439 // leaks like a sieve. 6440 for (unsigned i = 0; i != NumComponents; ++i) { 6441 const OffsetOfComponent &OC = CompPtr[i]; 6442 if (OC.isBrackets) { 6443 // Offset of an array sub-field. TODO: Should we allow vector elements? 6444 const ArrayType *AT = Context.getAsArrayType(Res->getType()); 6445 if (!AT) { 6446 Res->Destroy(Context); 6447 return ExprError(Diag(OC.LocEnd, diag::err_offsetof_array_type) 6448 << Res->getType()); 6449 } 6450 6451 // FIXME: C++: Verify that operator[] isn't overloaded. 6452 6453 // Promote the array so it looks more like a normal array subscript 6454 // expression. 6455 DefaultFunctionArrayConversion(Res); 6456 6457 // C99 6.5.2.1p1 6458 Expr *Idx = static_cast<Expr*>(OC.U.E); 6459 // FIXME: Leaks Res 6460 if (!Idx->isTypeDependent() && !Idx->getType()->isIntegerType()) 6461 return ExprError(Diag(Idx->getLocStart(), 6462 diag::err_typecheck_subscript_not_integer) 6463 << Idx->getSourceRange()); 6464 6465 Res = new (Context) ArraySubscriptExpr(Res, Idx, AT->getElementType(), 6466 OC.LocEnd); 6467 continue; 6468 } 6469 6470 const RecordType *RC = Res->getType()->getAs<RecordType>(); 6471 if (!RC) { 6472 Res->Destroy(Context); 6473 return ExprError(Diag(OC.LocEnd, diag::err_offsetof_record_type) 6474 << Res->getType()); 6475 } 6476 6477 // Get the decl corresponding to this. 6478 RecordDecl *RD = RC->getDecl(); 6479 if (CXXRecordDecl *CRD = dyn_cast<CXXRecordDecl>(RD)) { 6480 if (!CRD->isPOD() && !DidWarnAboutNonPOD) { 6481 switch (ExprEvalContexts.back().Context ) { 6482 case Unevaluated: 6483 // The argument will never be evaluated, so don't complain. 6484 break; 6485 6486 case PotentiallyEvaluated: 6487 ExprError(Diag(BuiltinLoc, diag::warn_offsetof_non_pod_type) 6488 << SourceRange(CompPtr[0].LocStart, OC.LocEnd) 6489 << Res->getType()); 6490 DidWarnAboutNonPOD = true; 6491 break; 6492 6493 case PotentiallyPotentiallyEvaluated: 6494 ExprEvalContexts.back().addDiagnostic(BuiltinLoc, 6495 PDiag(diag::warn_offsetof_non_pod_type) 6496 << SourceRange(CompPtr[0].LocStart, OC.LocEnd) 6497 << Res->getType()); 6498 DidWarnAboutNonPOD = true; 6499 break; 6500 } 6501 } 6502 } 6503 6504 LookupResult R(*this, OC.U.IdentInfo, OC.LocStart, LookupMemberName); 6505 LookupQualifiedName(R, RD); 6506 6507 FieldDecl *MemberDecl = R.getAsSingle<FieldDecl>(); 6508 // FIXME: Leaks Res 6509 if (!MemberDecl) 6510 return ExprError(Diag(BuiltinLoc, diag::err_no_member) 6511 << OC.U.IdentInfo << RD << SourceRange(OC.LocStart, OC.LocEnd)); 6512 6513 // FIXME: C++: Verify that MemberDecl isn't a static field. 6514 // FIXME: Verify that MemberDecl isn't a bitfield. 6515 if (cast<RecordDecl>(MemberDecl->getDeclContext())->isAnonymousStructOrUnion()) { 6516 Res = BuildAnonymousStructUnionMemberReference( 6517 OC.LocEnd, MemberDecl, Res, OC.LocEnd).takeAs<Expr>(); 6518 } else { 6519 PerformObjectMemberConversion(Res, MemberDecl); 6520 // MemberDecl->getType() doesn't get the right qualifiers, but it 6521 // doesn't matter here. 6522 Res = new (Context) MemberExpr(Res, false, MemberDecl, OC.LocEnd, 6523 MemberDecl->getType().getNonReferenceType()); 6524 } 6525 } 6526 } 6527 6528 return Owned(new (Context) UnaryOperator(Res, UnaryOperator::OffsetOf, 6529 Context.getSizeType(), BuiltinLoc)); 6530} 6531 6532 6533Sema::OwningExprResult Sema::ActOnTypesCompatibleExpr(SourceLocation BuiltinLoc, 6534 TypeTy *arg1,TypeTy *arg2, 6535 SourceLocation RPLoc) { 6536 // FIXME: Preserve type source info. 6537 QualType argT1 = GetTypeFromParser(arg1); 6538 QualType argT2 = GetTypeFromParser(arg2); 6539 6540 assert((!argT1.isNull() && !argT2.isNull()) && "Missing type argument(s)"); 6541 6542 if (getLangOptions().CPlusPlus) { 6543 Diag(BuiltinLoc, diag::err_types_compatible_p_in_cplusplus) 6544 << SourceRange(BuiltinLoc, RPLoc); 6545 return ExprError(); 6546 } 6547 6548 return Owned(new (Context) TypesCompatibleExpr(Context.IntTy, BuiltinLoc, 6549 argT1, argT2, RPLoc)); 6550} 6551 6552Sema::OwningExprResult Sema::ActOnChooseExpr(SourceLocation BuiltinLoc, 6553 ExprArg cond, 6554 ExprArg expr1, ExprArg expr2, 6555 SourceLocation RPLoc) { 6556 Expr *CondExpr = static_cast<Expr*>(cond.get()); 6557 Expr *LHSExpr = static_cast<Expr*>(expr1.get()); 6558 Expr *RHSExpr = static_cast<Expr*>(expr2.get()); 6559 6560 assert((CondExpr && LHSExpr && RHSExpr) && "Missing type argument(s)"); 6561 6562 QualType resType; 6563 bool ValueDependent = false; 6564 if (CondExpr->isTypeDependent() || CondExpr->isValueDependent()) { 6565 resType = Context.DependentTy; 6566 ValueDependent = true; 6567 } else { 6568 // The conditional expression is required to be a constant expression. 6569 llvm::APSInt condEval(32); 6570 SourceLocation ExpLoc; 6571 if (!CondExpr->isIntegerConstantExpr(condEval, Context, &ExpLoc)) 6572 return ExprError(Diag(ExpLoc, 6573 diag::err_typecheck_choose_expr_requires_constant) 6574 << CondExpr->getSourceRange()); 6575 6576 // If the condition is > zero, then the AST type is the same as the LSHExpr. 6577 resType = condEval.getZExtValue() ? LHSExpr->getType() : RHSExpr->getType(); 6578 ValueDependent = condEval.getZExtValue() ? LHSExpr->isValueDependent() 6579 : RHSExpr->isValueDependent(); 6580 } 6581 6582 cond.release(); expr1.release(); expr2.release(); 6583 return Owned(new (Context) ChooseExpr(BuiltinLoc, CondExpr, LHSExpr, RHSExpr, 6584 resType, RPLoc, 6585 resType->isDependentType(), 6586 ValueDependent)); 6587} 6588 6589//===----------------------------------------------------------------------===// 6590// Clang Extensions. 6591//===----------------------------------------------------------------------===// 6592 6593/// ActOnBlockStart - This callback is invoked when a block literal is started. 6594void Sema::ActOnBlockStart(SourceLocation CaretLoc, Scope *BlockScope) { 6595 // Analyze block parameters. 6596 BlockSemaInfo *BSI = new BlockSemaInfo(); 6597 6598 // Add BSI to CurBlock. 6599 BSI->PrevBlockInfo = CurBlock; 6600 CurBlock = BSI; 6601 6602 BSI->ReturnType = QualType(); 6603 BSI->TheScope = BlockScope; 6604 BSI->hasBlockDeclRefExprs = false; 6605 BSI->hasPrototype = false; 6606 BSI->SavedFunctionNeedsScopeChecking = CurFunctionNeedsScopeChecking; 6607 CurFunctionNeedsScopeChecking = false; 6608 6609 BSI->TheDecl = BlockDecl::Create(Context, CurContext, CaretLoc); 6610 CurContext->addDecl(BSI->TheDecl); 6611 PushDeclContext(BlockScope, BSI->TheDecl); 6612} 6613 6614void Sema::ActOnBlockArguments(Declarator &ParamInfo, Scope *CurScope) { 6615 assert(ParamInfo.getIdentifier()==0 && "block-id should have no identifier!"); 6616 6617 if (ParamInfo.getNumTypeObjects() == 0 6618 || ParamInfo.getTypeObject(0).Kind != DeclaratorChunk::Function) { 6619 ProcessDeclAttributes(CurScope, CurBlock->TheDecl, ParamInfo); 6620 QualType T = GetTypeForDeclarator(ParamInfo, CurScope); 6621 6622 if (T->isArrayType()) { 6623 Diag(ParamInfo.getSourceRange().getBegin(), 6624 diag::err_block_returns_array); 6625 return; 6626 } 6627 6628 // The parameter list is optional, if there was none, assume (). 6629 if (!T->isFunctionType()) 6630 T = Context.getFunctionType(T, NULL, 0, 0, 0); 6631 6632 CurBlock->hasPrototype = true; 6633 CurBlock->isVariadic = false; 6634 // Check for a valid sentinel attribute on this block. 6635 if (CurBlock->TheDecl->getAttr<SentinelAttr>()) { 6636 Diag(ParamInfo.getAttributes()->getLoc(), 6637 diag::warn_attribute_sentinel_not_variadic) << 1; 6638 // FIXME: remove the attribute. 6639 } 6640 QualType RetTy = T.getTypePtr()->getAs<FunctionType>()->getResultType(); 6641 6642 // Do not allow returning a objc interface by-value. 6643 if (RetTy->isObjCInterfaceType()) { 6644 Diag(ParamInfo.getSourceRange().getBegin(), 6645 diag::err_object_cannot_be_passed_returned_by_value) << 0 << RetTy; 6646 return; 6647 } 6648 return; 6649 } 6650 6651 // Analyze arguments to block. 6652 assert(ParamInfo.getTypeObject(0).Kind == DeclaratorChunk::Function && 6653 "Not a function declarator!"); 6654 DeclaratorChunk::FunctionTypeInfo &FTI = ParamInfo.getTypeObject(0).Fun; 6655 6656 CurBlock->hasPrototype = FTI.hasPrototype; 6657 CurBlock->isVariadic = true; 6658 6659 // Check for C99 6.7.5.3p10 - foo(void) is a non-varargs function that takes 6660 // no arguments, not a function that takes a single void argument. 6661 if (FTI.hasPrototype && 6662 FTI.NumArgs == 1 && !FTI.isVariadic && FTI.ArgInfo[0].Ident == 0 && 6663 (!FTI.ArgInfo[0].Param.getAs<ParmVarDecl>()->getType().getCVRQualifiers()&& 6664 FTI.ArgInfo[0].Param.getAs<ParmVarDecl>()->getType()->isVoidType())) { 6665 // empty arg list, don't push any params. 6666 CurBlock->isVariadic = false; 6667 } else if (FTI.hasPrototype) { 6668 for (unsigned i = 0, e = FTI.NumArgs; i != e; ++i) 6669 CurBlock->Params.push_back(FTI.ArgInfo[i].Param.getAs<ParmVarDecl>()); 6670 CurBlock->isVariadic = FTI.isVariadic; 6671 } 6672 CurBlock->TheDecl->setParams(Context, CurBlock->Params.data(), 6673 CurBlock->Params.size()); 6674 CurBlock->TheDecl->setIsVariadic(CurBlock->isVariadic); 6675 ProcessDeclAttributes(CurScope, CurBlock->TheDecl, ParamInfo); 6676 for (BlockDecl::param_iterator AI = CurBlock->TheDecl->param_begin(), 6677 E = CurBlock->TheDecl->param_end(); AI != E; ++AI) 6678 // If this has an identifier, add it to the scope stack. 6679 if ((*AI)->getIdentifier()) 6680 PushOnScopeChains(*AI, CurBlock->TheScope); 6681 6682 // Check for a valid sentinel attribute on this block. 6683 if (!CurBlock->isVariadic && 6684 CurBlock->TheDecl->getAttr<SentinelAttr>()) { 6685 Diag(ParamInfo.getAttributes()->getLoc(), 6686 diag::warn_attribute_sentinel_not_variadic) << 1; 6687 // FIXME: remove the attribute. 6688 } 6689 6690 // Analyze the return type. 6691 QualType T = GetTypeForDeclarator(ParamInfo, CurScope); 6692 QualType RetTy = T->getAs<FunctionType>()->getResultType(); 6693 6694 // Do not allow returning a objc interface by-value. 6695 if (RetTy->isObjCInterfaceType()) { 6696 Diag(ParamInfo.getSourceRange().getBegin(), 6697 diag::err_object_cannot_be_passed_returned_by_value) << 0 << RetTy; 6698 } else if (!RetTy->isDependentType()) 6699 CurBlock->ReturnType = RetTy; 6700} 6701 6702/// ActOnBlockError - If there is an error parsing a block, this callback 6703/// is invoked to pop the information about the block from the action impl. 6704void Sema::ActOnBlockError(SourceLocation CaretLoc, Scope *CurScope) { 6705 // Ensure that CurBlock is deleted. 6706 llvm::OwningPtr<BlockSemaInfo> CC(CurBlock); 6707 6708 CurFunctionNeedsScopeChecking = CurBlock->SavedFunctionNeedsScopeChecking; 6709 6710 // Pop off CurBlock, handle nested blocks. 6711 PopDeclContext(); 6712 CurBlock = CurBlock->PrevBlockInfo; 6713 // FIXME: Delete the ParmVarDecl objects as well??? 6714} 6715 6716/// ActOnBlockStmtExpr - This is called when the body of a block statement 6717/// literal was successfully completed. ^(int x){...} 6718Sema::OwningExprResult Sema::ActOnBlockStmtExpr(SourceLocation CaretLoc, 6719 StmtArg body, Scope *CurScope) { 6720 // If blocks are disabled, emit an error. 6721 if (!LangOpts.Blocks) 6722 Diag(CaretLoc, diag::err_blocks_disable); 6723 6724 // Ensure that CurBlock is deleted. 6725 llvm::OwningPtr<BlockSemaInfo> BSI(CurBlock); 6726 6727 PopDeclContext(); 6728 6729 // Pop off CurBlock, handle nested blocks. 6730 CurBlock = CurBlock->PrevBlockInfo; 6731 6732 QualType RetTy = Context.VoidTy; 6733 if (!BSI->ReturnType.isNull()) 6734 RetTy = BSI->ReturnType; 6735 6736 llvm::SmallVector<QualType, 8> ArgTypes; 6737 for (unsigned i = 0, e = BSI->Params.size(); i != e; ++i) 6738 ArgTypes.push_back(BSI->Params[i]->getType()); 6739 6740 bool NoReturn = BSI->TheDecl->getAttr<NoReturnAttr>(); 6741 QualType BlockTy; 6742 if (!BSI->hasPrototype) 6743 BlockTy = Context.getFunctionType(RetTy, 0, 0, false, 0, false, false, 0, 0, 6744 NoReturn); 6745 else 6746 BlockTy = Context.getFunctionType(RetTy, ArgTypes.data(), ArgTypes.size(), 6747 BSI->isVariadic, 0, false, false, 0, 0, 6748 NoReturn); 6749 6750 // FIXME: Check that return/parameter types are complete/non-abstract 6751 DiagnoseUnusedParameters(BSI->Params.begin(), BSI->Params.end()); 6752 BlockTy = Context.getBlockPointerType(BlockTy); 6753 6754 // If needed, diagnose invalid gotos and switches in the block. 6755 if (CurFunctionNeedsScopeChecking) 6756 DiagnoseInvalidJumps(static_cast<CompoundStmt*>(body.get())); 6757 CurFunctionNeedsScopeChecking = BSI->SavedFunctionNeedsScopeChecking; 6758 6759 BSI->TheDecl->setBody(body.takeAs<CompoundStmt>()); 6760 CheckFallThroughForBlock(BlockTy, BSI->TheDecl->getBody()); 6761 return Owned(new (Context) BlockExpr(BSI->TheDecl, BlockTy, 6762 BSI->hasBlockDeclRefExprs)); 6763} 6764 6765Sema::OwningExprResult Sema::ActOnVAArg(SourceLocation BuiltinLoc, 6766 ExprArg expr, TypeTy *type, 6767 SourceLocation RPLoc) { 6768 QualType T = GetTypeFromParser(type); 6769 Expr *E = static_cast<Expr*>(expr.get()); 6770 Expr *OrigExpr = E; 6771 6772 InitBuiltinVaListType(); 6773 6774 // Get the va_list type 6775 QualType VaListType = Context.getBuiltinVaListType(); 6776 if (VaListType->isArrayType()) { 6777 // Deal with implicit array decay; for example, on x86-64, 6778 // va_list is an array, but it's supposed to decay to 6779 // a pointer for va_arg. 6780 VaListType = Context.getArrayDecayedType(VaListType); 6781 // Make sure the input expression also decays appropriately. 6782 UsualUnaryConversions(E); 6783 } else { 6784 // Otherwise, the va_list argument must be an l-value because 6785 // it is modified by va_arg. 6786 if (!E->isTypeDependent() && 6787 CheckForModifiableLvalue(E, BuiltinLoc, *this)) 6788 return ExprError(); 6789 } 6790 6791 if (!E->isTypeDependent() && 6792 !Context.hasSameType(VaListType, E->getType())) { 6793 return ExprError(Diag(E->getLocStart(), 6794 diag::err_first_argument_to_va_arg_not_of_type_va_list) 6795 << OrigExpr->getType() << E->getSourceRange()); 6796 } 6797 6798 // FIXME: Check that type is complete/non-abstract 6799 // FIXME: Warn if a non-POD type is passed in. 6800 6801 expr.release(); 6802 return Owned(new (Context) VAArgExpr(BuiltinLoc, E, T.getNonReferenceType(), 6803 RPLoc)); 6804} 6805 6806Sema::OwningExprResult Sema::ActOnGNUNullExpr(SourceLocation TokenLoc) { 6807 // The type of __null will be int or long, depending on the size of 6808 // pointers on the target. 6809 QualType Ty; 6810 if (Context.Target.getPointerWidth(0) == Context.Target.getIntWidth()) 6811 Ty = Context.IntTy; 6812 else 6813 Ty = Context.LongTy; 6814 6815 return Owned(new (Context) GNUNullExpr(Ty, TokenLoc)); 6816} 6817 6818static void 6819MakeObjCStringLiteralCodeModificationHint(Sema& SemaRef, 6820 QualType DstType, 6821 Expr *SrcExpr, 6822 CodeModificationHint &Hint) { 6823 if (!SemaRef.getLangOptions().ObjC1) 6824 return; 6825 6826 const ObjCObjectPointerType *PT = DstType->getAs<ObjCObjectPointerType>(); 6827 if (!PT) 6828 return; 6829 6830 // Check if the destination is of type 'id'. 6831 if (!PT->isObjCIdType()) { 6832 // Check if the destination is the 'NSString' interface. 6833 const ObjCInterfaceDecl *ID = PT->getInterfaceDecl(); 6834 if (!ID || !ID->getIdentifier()->isStr("NSString")) 6835 return; 6836 } 6837 6838 // Strip off any parens and casts. 6839 StringLiteral *SL = dyn_cast<StringLiteral>(SrcExpr->IgnoreParenCasts()); 6840 if (!SL || SL->isWide()) 6841 return; 6842 6843 Hint = CodeModificationHint::CreateInsertion(SL->getLocStart(), "@"); 6844} 6845 6846bool Sema::DiagnoseAssignmentResult(AssignConvertType ConvTy, 6847 SourceLocation Loc, 6848 QualType DstType, QualType SrcType, 6849 Expr *SrcExpr, const char *Flavor) { 6850 // Decode the result (notice that AST's are still created for extensions). 6851 bool isInvalid = false; 6852 unsigned DiagKind; 6853 CodeModificationHint Hint; 6854 6855 switch (ConvTy) { 6856 default: assert(0 && "Unknown conversion type"); 6857 case Compatible: return false; 6858 case PointerToInt: 6859 DiagKind = diag::ext_typecheck_convert_pointer_int; 6860 break; 6861 case IntToPointer: 6862 DiagKind = diag::ext_typecheck_convert_int_pointer; 6863 break; 6864 case IncompatiblePointer: 6865 MakeObjCStringLiteralCodeModificationHint(*this, DstType, SrcExpr, Hint); 6866 DiagKind = diag::ext_typecheck_convert_incompatible_pointer; 6867 break; 6868 case IncompatiblePointerSign: 6869 DiagKind = diag::ext_typecheck_convert_incompatible_pointer_sign; 6870 break; 6871 case FunctionVoidPointer: 6872 DiagKind = diag::ext_typecheck_convert_pointer_void_func; 6873 break; 6874 case CompatiblePointerDiscardsQualifiers: 6875 // If the qualifiers lost were because we were applying the 6876 // (deprecated) C++ conversion from a string literal to a char* 6877 // (or wchar_t*), then there was no error (C++ 4.2p2). FIXME: 6878 // Ideally, this check would be performed in 6879 // CheckPointerTypesForAssignment. However, that would require a 6880 // bit of refactoring (so that the second argument is an 6881 // expression, rather than a type), which should be done as part 6882 // of a larger effort to fix CheckPointerTypesForAssignment for 6883 // C++ semantics. 6884 if (getLangOptions().CPlusPlus && 6885 IsStringLiteralToNonConstPointerConversion(SrcExpr, DstType)) 6886 return false; 6887 DiagKind = diag::ext_typecheck_convert_discards_qualifiers; 6888 break; 6889 case IncompatibleNestedPointerQualifiers: 6890 DiagKind = diag::ext_nested_pointer_qualifier_mismatch; 6891 break; 6892 case IntToBlockPointer: 6893 DiagKind = diag::err_int_to_block_pointer; 6894 break; 6895 case IncompatibleBlockPointer: 6896 DiagKind = diag::err_typecheck_convert_incompatible_block_pointer; 6897 break; 6898 case IncompatibleObjCQualifiedId: 6899 // FIXME: Diagnose the problem in ObjCQualifiedIdTypesAreCompatible, since 6900 // it can give a more specific diagnostic. 6901 DiagKind = diag::warn_incompatible_qualified_id; 6902 break; 6903 case IncompatibleVectors: 6904 DiagKind = diag::warn_incompatible_vectors; 6905 break; 6906 case Incompatible: 6907 DiagKind = diag::err_typecheck_convert_incompatible; 6908 isInvalid = true; 6909 break; 6910 } 6911 6912 Diag(Loc, DiagKind) << DstType << SrcType << Flavor 6913 << SrcExpr->getSourceRange() << Hint; 6914 return isInvalid; 6915} 6916 6917bool Sema::VerifyIntegerConstantExpression(const Expr *E, llvm::APSInt *Result){ 6918 llvm::APSInt ICEResult; 6919 if (E->isIntegerConstantExpr(ICEResult, Context)) { 6920 if (Result) 6921 *Result = ICEResult; 6922 return false; 6923 } 6924 6925 Expr::EvalResult EvalResult; 6926 6927 if (!E->Evaluate(EvalResult, Context) || !EvalResult.Val.isInt() || 6928 EvalResult.HasSideEffects) { 6929 Diag(E->getExprLoc(), diag::err_expr_not_ice) << E->getSourceRange(); 6930 6931 if (EvalResult.Diag) { 6932 // We only show the note if it's not the usual "invalid subexpression" 6933 // or if it's actually in a subexpression. 6934 if (EvalResult.Diag != diag::note_invalid_subexpr_in_ice || 6935 E->IgnoreParens() != EvalResult.DiagExpr->IgnoreParens()) 6936 Diag(EvalResult.DiagLoc, EvalResult.Diag); 6937 } 6938 6939 return true; 6940 } 6941 6942 Diag(E->getExprLoc(), diag::ext_expr_not_ice) << 6943 E->getSourceRange(); 6944 6945 if (EvalResult.Diag && 6946 Diags.getDiagnosticLevel(diag::ext_expr_not_ice) != Diagnostic::Ignored) 6947 Diag(EvalResult.DiagLoc, EvalResult.Diag); 6948 6949 if (Result) 6950 *Result = EvalResult.Val.getInt(); 6951 return false; 6952} 6953 6954void 6955Sema::PushExpressionEvaluationContext(ExpressionEvaluationContext NewContext) { 6956 ExprEvalContexts.push_back( 6957 ExpressionEvaluationContextRecord(NewContext, ExprTemporaries.size())); 6958} 6959 6960void 6961Sema::PopExpressionEvaluationContext() { 6962 // Pop the current expression evaluation context off the stack. 6963 ExpressionEvaluationContextRecord Rec = ExprEvalContexts.back(); 6964 ExprEvalContexts.pop_back(); 6965 6966 if (Rec.Context == PotentiallyPotentiallyEvaluated) { 6967 if (Rec.PotentiallyReferenced) { 6968 // Mark any remaining declarations in the current position of the stack 6969 // as "referenced". If they were not meant to be referenced, semantic 6970 // analysis would have eliminated them (e.g., in ActOnCXXTypeId). 6971 for (PotentiallyReferencedDecls::iterator 6972 I = Rec.PotentiallyReferenced->begin(), 6973 IEnd = Rec.PotentiallyReferenced->end(); 6974 I != IEnd; ++I) 6975 MarkDeclarationReferenced(I->first, I->second); 6976 } 6977 6978 if (Rec.PotentiallyDiagnosed) { 6979 // Emit any pending diagnostics. 6980 for (PotentiallyEmittedDiagnostics::iterator 6981 I = Rec.PotentiallyDiagnosed->begin(), 6982 IEnd = Rec.PotentiallyDiagnosed->end(); 6983 I != IEnd; ++I) 6984 Diag(I->first, I->second); 6985 } 6986 } 6987 6988 // When are coming out of an unevaluated context, clear out any 6989 // temporaries that we may have created as part of the evaluation of 6990 // the expression in that context: they aren't relevant because they 6991 // will never be constructed. 6992 if (Rec.Context == Unevaluated && 6993 ExprTemporaries.size() > Rec.NumTemporaries) 6994 ExprTemporaries.erase(ExprTemporaries.begin() + Rec.NumTemporaries, 6995 ExprTemporaries.end()); 6996 6997 // Destroy the popped expression evaluation record. 6998 Rec.Destroy(); 6999} 7000 7001/// \brief Note that the given declaration was referenced in the source code. 7002/// 7003/// This routine should be invoke whenever a given declaration is referenced 7004/// in the source code, and where that reference occurred. If this declaration 7005/// reference means that the the declaration is used (C++ [basic.def.odr]p2, 7006/// C99 6.9p3), then the declaration will be marked as used. 7007/// 7008/// \param Loc the location where the declaration was referenced. 7009/// 7010/// \param D the declaration that has been referenced by the source code. 7011void Sema::MarkDeclarationReferenced(SourceLocation Loc, Decl *D) { 7012 assert(D && "No declaration?"); 7013 7014 if (D->isUsed()) 7015 return; 7016 7017 // Mark a parameter or variable declaration "used", regardless of whether we're in a 7018 // template or not. The reason for this is that unevaluated expressions 7019 // (e.g. (void)sizeof()) constitute a use for warning purposes (-Wunused-variables and 7020 // -Wunused-parameters) 7021 if (isa<ParmVarDecl>(D) || 7022 (isa<VarDecl>(D) && D->getDeclContext()->isFunctionOrMethod())) 7023 D->setUsed(true); 7024 7025 // Do not mark anything as "used" within a dependent context; wait for 7026 // an instantiation. 7027 if (CurContext->isDependentContext()) 7028 return; 7029 7030 switch (ExprEvalContexts.back().Context) { 7031 case Unevaluated: 7032 // We are in an expression that is not potentially evaluated; do nothing. 7033 return; 7034 7035 case PotentiallyEvaluated: 7036 // We are in a potentially-evaluated expression, so this declaration is 7037 // "used"; handle this below. 7038 break; 7039 7040 case PotentiallyPotentiallyEvaluated: 7041 // We are in an expression that may be potentially evaluated; queue this 7042 // declaration reference until we know whether the expression is 7043 // potentially evaluated. 7044 ExprEvalContexts.back().addReferencedDecl(Loc, D); 7045 return; 7046 } 7047 7048 // Note that this declaration has been used. 7049 if (CXXConstructorDecl *Constructor = dyn_cast<CXXConstructorDecl>(D)) { 7050 unsigned TypeQuals; 7051 if (Constructor->isImplicit() && Constructor->isDefaultConstructor()) { 7052 if (!Constructor->isUsed()) 7053 DefineImplicitDefaultConstructor(Loc, Constructor); 7054 } else if (Constructor->isImplicit() && 7055 Constructor->isCopyConstructor(Context, TypeQuals)) { 7056 if (!Constructor->isUsed()) 7057 DefineImplicitCopyConstructor(Loc, Constructor, TypeQuals); 7058 } 7059 7060 MaybeMarkVirtualMembersReferenced(Loc, Constructor); 7061 } else if (CXXDestructorDecl *Destructor = dyn_cast<CXXDestructorDecl>(D)) { 7062 if (Destructor->isImplicit() && !Destructor->isUsed()) 7063 DefineImplicitDestructor(Loc, Destructor); 7064 7065 } else if (CXXMethodDecl *MethodDecl = dyn_cast<CXXMethodDecl>(D)) { 7066 if (MethodDecl->isImplicit() && MethodDecl->isOverloadedOperator() && 7067 MethodDecl->getOverloadedOperator() == OO_Equal) { 7068 if (!MethodDecl->isUsed()) 7069 DefineImplicitOverloadedAssign(Loc, MethodDecl); 7070 } 7071 } 7072 if (FunctionDecl *Function = dyn_cast<FunctionDecl>(D)) { 7073 // Implicit instantiation of function templates and member functions of 7074 // class templates. 7075 if (!Function->getBody() && Function->isImplicitlyInstantiable()) { 7076 bool AlreadyInstantiated = false; 7077 if (FunctionTemplateSpecializationInfo *SpecInfo 7078 = Function->getTemplateSpecializationInfo()) { 7079 if (SpecInfo->getPointOfInstantiation().isInvalid()) 7080 SpecInfo->setPointOfInstantiation(Loc); 7081 else if (SpecInfo->getTemplateSpecializationKind() 7082 == TSK_ImplicitInstantiation) 7083 AlreadyInstantiated = true; 7084 } else if (MemberSpecializationInfo *MSInfo 7085 = Function->getMemberSpecializationInfo()) { 7086 if (MSInfo->getPointOfInstantiation().isInvalid()) 7087 MSInfo->setPointOfInstantiation(Loc); 7088 else if (MSInfo->getTemplateSpecializationKind() 7089 == TSK_ImplicitInstantiation) 7090 AlreadyInstantiated = true; 7091 } 7092 7093 if (!AlreadyInstantiated) 7094 PendingImplicitInstantiations.push_back(std::make_pair(Function, Loc)); 7095 } 7096 7097 // FIXME: keep track of references to static functions 7098 Function->setUsed(true); 7099 return; 7100 } 7101 7102 if (VarDecl *Var = dyn_cast<VarDecl>(D)) { 7103 // Implicit instantiation of static data members of class templates. 7104 if (Var->isStaticDataMember() && 7105 Var->getInstantiatedFromStaticDataMember()) { 7106 MemberSpecializationInfo *MSInfo = Var->getMemberSpecializationInfo(); 7107 assert(MSInfo && "Missing member specialization information?"); 7108 if (MSInfo->getPointOfInstantiation().isInvalid() && 7109 MSInfo->getTemplateSpecializationKind()== TSK_ImplicitInstantiation) { 7110 MSInfo->setPointOfInstantiation(Loc); 7111 PendingImplicitInstantiations.push_back(std::make_pair(Var, Loc)); 7112 } 7113 } 7114 7115 // FIXME: keep track of references to static data? 7116 7117 D->setUsed(true); 7118 return; 7119 } 7120} 7121 7122bool Sema::CheckCallReturnType(QualType ReturnType, SourceLocation Loc, 7123 CallExpr *CE, FunctionDecl *FD) { 7124 if (ReturnType->isVoidType() || !ReturnType->isIncompleteType()) 7125 return false; 7126 7127 PartialDiagnostic Note = 7128 FD ? PDiag(diag::note_function_with_incomplete_return_type_declared_here) 7129 << FD->getDeclName() : PDiag(); 7130 SourceLocation NoteLoc = FD ? FD->getLocation() : SourceLocation(); 7131 7132 if (RequireCompleteType(Loc, ReturnType, 7133 FD ? 7134 PDiag(diag::err_call_function_incomplete_return) 7135 << CE->getSourceRange() << FD->getDeclName() : 7136 PDiag(diag::err_call_incomplete_return) 7137 << CE->getSourceRange(), 7138 std::make_pair(NoteLoc, Note))) 7139 return true; 7140 7141 return false; 7142} 7143 7144// Diagnose the common s/=/==/ typo. Note that adding parentheses 7145// will prevent this condition from triggering, which is what we want. 7146void Sema::DiagnoseAssignmentAsCondition(Expr *E) { 7147 SourceLocation Loc; 7148 7149 unsigned diagnostic = diag::warn_condition_is_assignment; 7150 7151 if (isa<BinaryOperator>(E)) { 7152 BinaryOperator *Op = cast<BinaryOperator>(E); 7153 if (Op->getOpcode() != BinaryOperator::Assign) 7154 return; 7155 7156 // Greylist some idioms by putting them into a warning subcategory. 7157 if (ObjCMessageExpr *ME 7158 = dyn_cast<ObjCMessageExpr>(Op->getRHS()->IgnoreParenCasts())) { 7159 Selector Sel = ME->getSelector(); 7160 7161 // self = [<foo> init...] 7162 if (isSelfExpr(Op->getLHS()) 7163 && Sel.getIdentifierInfoForSlot(0)->getName().startswith("init")) 7164 diagnostic = diag::warn_condition_is_idiomatic_assignment; 7165 7166 // <foo> = [<bar> nextObject] 7167 else if (Sel.isUnarySelector() && 7168 Sel.getIdentifierInfoForSlot(0)->getName() == "nextObject") 7169 diagnostic = diag::warn_condition_is_idiomatic_assignment; 7170 } 7171 7172 Loc = Op->getOperatorLoc(); 7173 } else if (isa<CXXOperatorCallExpr>(E)) { 7174 CXXOperatorCallExpr *Op = cast<CXXOperatorCallExpr>(E); 7175 if (Op->getOperator() != OO_Equal) 7176 return; 7177 7178 Loc = Op->getOperatorLoc(); 7179 } else { 7180 // Not an assignment. 7181 return; 7182 } 7183 7184 SourceLocation Open = E->getSourceRange().getBegin(); 7185 SourceLocation Close = PP.getLocForEndOfToken(E->getSourceRange().getEnd()); 7186 7187 Diag(Loc, diagnostic) 7188 << E->getSourceRange() 7189 << CodeModificationHint::CreateInsertion(Open, "(") 7190 << CodeModificationHint::CreateInsertion(Close, ")"); 7191} 7192 7193bool Sema::CheckBooleanCondition(Expr *&E, SourceLocation Loc) { 7194 DiagnoseAssignmentAsCondition(E); 7195 7196 if (!E->isTypeDependent()) { 7197 DefaultFunctionArrayConversion(E); 7198 7199 QualType T = E->getType(); 7200 7201 if (getLangOptions().CPlusPlus) { 7202 if (CheckCXXBooleanCondition(E)) // C++ 6.4p4 7203 return true; 7204 } else if (!T->isScalarType()) { // C99 6.8.4.1p1 7205 Diag(Loc, diag::err_typecheck_statement_requires_scalar) 7206 << T << E->getSourceRange(); 7207 return true; 7208 } 7209 } 7210 7211 return false; 7212} 7213