SemaExpr.cpp revision a0494768db49126986e425913f6ad77f9e3dfdce
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 "SemaInit.h" 16#include "Lookup.h" 17#include "AnalysisBasedWarnings.h" 18#include "clang/AST/ASTContext.h" 19#include "clang/AST/DeclObjC.h" 20#include "clang/AST/DeclTemplate.h" 21#include "clang/AST/ExprCXX.h" 22#include "clang/AST/ExprObjC.h" 23#include "clang/Basic/PartialDiagnostic.h" 24#include "clang/Basic/SourceManager.h" 25#include "clang/Basic/TargetInfo.h" 26#include "clang/Lex/LiteralSupport.h" 27#include "clang/Lex/Preprocessor.h" 28#include "clang/Parse/DeclSpec.h" 29#include "clang/Parse/Designator.h" 30#include "clang/Parse/Scope.h" 31#include "clang/Parse/Template.h" 32using namespace clang; 33 34 35/// \brief Determine whether the use of this declaration is valid, and 36/// emit any corresponding diagnostics. 37/// 38/// This routine diagnoses various problems with referencing 39/// declarations that can occur when using a declaration. For example, 40/// it might warn if a deprecated or unavailable declaration is being 41/// used, or produce an error (and return true) if a C++0x deleted 42/// function is being used. 43/// 44/// If IgnoreDeprecated is set to true, this should not want about deprecated 45/// decls. 46/// 47/// \returns true if there was an error (this declaration cannot be 48/// referenced), false otherwise. 49/// 50bool Sema::DiagnoseUseOfDecl(NamedDecl *D, SourceLocation Loc) { 51 // See if the decl is deprecated. 52 if (D->getAttr<DeprecatedAttr>()) { 53 EmitDeprecationWarning(D, Loc); 54 } 55 56 // See if the decl is unavailable 57 if (D->getAttr<UnavailableAttr>()) { 58 Diag(Loc, diag::warn_unavailable) << D->getDeclName(); 59 Diag(D->getLocation(), diag::note_unavailable_here) << 0; 60 } 61 62 // See if this is a deleted function. 63 if (FunctionDecl *FD = dyn_cast<FunctionDecl>(D)) { 64 if (FD->isDeleted()) { 65 Diag(Loc, diag::err_deleted_function_use); 66 Diag(D->getLocation(), diag::note_unavailable_here) << true; 67 return true; 68 } 69 } 70 71 return false; 72} 73 74/// DiagnoseSentinelCalls - This routine checks on method dispatch calls 75/// (and other functions in future), which have been declared with sentinel 76/// attribute. It warns if call does not have the sentinel argument. 77/// 78void Sema::DiagnoseSentinelCalls(NamedDecl *D, SourceLocation Loc, 79 Expr **Args, unsigned NumArgs) { 80 const SentinelAttr *attr = D->getAttr<SentinelAttr>(); 81 if (!attr) 82 return; 83 84 // FIXME: In C++0x, if any of the arguments are parameter pack 85 // expansions, we can't check for the sentinel now. 86 int sentinelPos = attr->getSentinel(); 87 int nullPos = attr->getNullPos(); 88 89 // FIXME. ObjCMethodDecl and FunctionDecl need be derived from the same common 90 // base class. Then we won't be needing two versions of the same code. 91 unsigned int i = 0; 92 bool warnNotEnoughArgs = false; 93 int isMethod = 0; 94 if (ObjCMethodDecl *MD = dyn_cast<ObjCMethodDecl>(D)) { 95 // skip over named parameters. 96 ObjCMethodDecl::param_iterator P, E = MD->param_end(); 97 for (P = MD->param_begin(); (P != E && i < NumArgs); ++P) { 98 if (nullPos) 99 --nullPos; 100 else 101 ++i; 102 } 103 warnNotEnoughArgs = (P != E || i >= NumArgs); 104 isMethod = 1; 105 } else if (FunctionDecl *FD = dyn_cast<FunctionDecl>(D)) { 106 // skip over named parameters. 107 ObjCMethodDecl::param_iterator P, E = FD->param_end(); 108 for (P = FD->param_begin(); (P != E && i < NumArgs); ++P) { 109 if (nullPos) 110 --nullPos; 111 else 112 ++i; 113 } 114 warnNotEnoughArgs = (P != E || i >= NumArgs); 115 } else if (VarDecl *V = dyn_cast<VarDecl>(D)) { 116 // block or function pointer call. 117 QualType Ty = V->getType(); 118 if (Ty->isBlockPointerType() || Ty->isFunctionPointerType()) { 119 const FunctionType *FT = Ty->isFunctionPointerType() 120 ? Ty->getAs<PointerType>()->getPointeeType()->getAs<FunctionType>() 121 : Ty->getAs<BlockPointerType>()->getPointeeType()->getAs<FunctionType>(); 122 if (const FunctionProtoType *Proto = dyn_cast<FunctionProtoType>(FT)) { 123 unsigned NumArgsInProto = Proto->getNumArgs(); 124 unsigned k; 125 for (k = 0; (k != NumArgsInProto && i < NumArgs); k++) { 126 if (nullPos) 127 --nullPos; 128 else 129 ++i; 130 } 131 warnNotEnoughArgs = (k != NumArgsInProto || i >= NumArgs); 132 } 133 if (Ty->isBlockPointerType()) 134 isMethod = 2; 135 } else 136 return; 137 } else 138 return; 139 140 if (warnNotEnoughArgs) { 141 Diag(Loc, diag::warn_not_enough_argument) << D->getDeclName(); 142 Diag(D->getLocation(), diag::note_sentinel_here) << isMethod; 143 return; 144 } 145 int sentinel = i; 146 while (sentinelPos > 0 && i < NumArgs-1) { 147 --sentinelPos; 148 ++i; 149 } 150 if (sentinelPos > 0) { 151 Diag(Loc, diag::warn_not_enough_argument) << D->getDeclName(); 152 Diag(D->getLocation(), diag::note_sentinel_here) << isMethod; 153 return; 154 } 155 while (i < NumArgs-1) { 156 ++i; 157 ++sentinel; 158 } 159 Expr *sentinelExpr = Args[sentinel]; 160 if (sentinelExpr && (!isa<GNUNullExpr>(sentinelExpr) && 161 !sentinelExpr->isTypeDependent() && 162 !sentinelExpr->isValueDependent() && 163 (!sentinelExpr->getType()->isPointerType() || 164 !sentinelExpr->isNullPointerConstant(Context, 165 Expr::NPC_ValueDependentIsNull)))) { 166 Diag(Loc, diag::warn_missing_sentinel) << isMethod; 167 Diag(D->getLocation(), diag::note_sentinel_here) << isMethod; 168 } 169 return; 170} 171 172SourceRange Sema::getExprRange(ExprTy *E) const { 173 Expr *Ex = (Expr *)E; 174 return Ex? Ex->getSourceRange() : SourceRange(); 175} 176 177//===----------------------------------------------------------------------===// 178// Standard Promotions and Conversions 179//===----------------------------------------------------------------------===// 180 181/// DefaultFunctionArrayConversion (C99 6.3.2.1p3, C99 6.3.2.1p4). 182void Sema::DefaultFunctionArrayConversion(Expr *&E) { 183 QualType Ty = E->getType(); 184 assert(!Ty.isNull() && "DefaultFunctionArrayConversion - missing type"); 185 186 if (Ty->isFunctionType()) 187 ImpCastExprToType(E, Context.getPointerType(Ty), 188 CastExpr::CK_FunctionToPointerDecay); 189 else if (Ty->isArrayType()) { 190 // In C90 mode, arrays only promote to pointers if the array expression is 191 // an lvalue. The relevant legalese is C90 6.2.2.1p3: "an lvalue that has 192 // type 'array of type' is converted to an expression that has type 'pointer 193 // to type'...". In C99 this was changed to: C99 6.3.2.1p3: "an expression 194 // that has type 'array of type' ...". The relevant change is "an lvalue" 195 // (C90) to "an expression" (C99). 196 // 197 // C++ 4.2p1: 198 // An lvalue or rvalue of type "array of N T" or "array of unknown bound of 199 // T" can be converted to an rvalue of type "pointer to T". 200 // 201 if (getLangOptions().C99 || getLangOptions().CPlusPlus || 202 E->isLvalue(Context) == Expr::LV_Valid) 203 ImpCastExprToType(E, Context.getArrayDecayedType(Ty), 204 CastExpr::CK_ArrayToPointerDecay); 205 } 206} 207 208void Sema::DefaultFunctionArrayLvalueConversion(Expr *&E) { 209 DefaultFunctionArrayConversion(E); 210 211 QualType Ty = E->getType(); 212 assert(!Ty.isNull() && "DefaultFunctionArrayLvalueConversion - missing type"); 213 if (!Ty->isDependentType() && Ty.hasQualifiers() && 214 (!getLangOptions().CPlusPlus || !Ty->isRecordType()) && 215 E->isLvalue(Context) == Expr::LV_Valid) { 216 // C++ [conv.lval]p1: 217 // [...] If T is a non-class type, the type of the rvalue is the 218 // cv-unqualified version of T. Otherwise, the type of the 219 // rvalue is T 220 // 221 // C99 6.3.2.1p2: 222 // If the lvalue has qualified type, the value has the unqualified 223 // version of the type of the lvalue; otherwise, the value has the 224 // type of the lvalue. 225 ImpCastExprToType(E, Ty.getUnqualifiedType(), CastExpr::CK_NoOp); 226 } 227} 228 229 230/// UsualUnaryConversions - Performs various conversions that are common to most 231/// operators (C99 6.3). The conversions of array and function types are 232/// sometimes surpressed. For example, the array->pointer conversion doesn't 233/// apply if the array is an argument to the sizeof or address (&) operators. 234/// In these instances, this routine should *not* be called. 235Expr *Sema::UsualUnaryConversions(Expr *&Expr) { 236 QualType Ty = Expr->getType(); 237 assert(!Ty.isNull() && "UsualUnaryConversions - missing type"); 238 239 // C99 6.3.1.1p2: 240 // 241 // The following may be used in an expression wherever an int or 242 // unsigned int may be used: 243 // - an object or expression with an integer type whose integer 244 // conversion rank is less than or equal to the rank of int 245 // and unsigned int. 246 // - A bit-field of type _Bool, int, signed int, or unsigned int. 247 // 248 // If an int can represent all values of the original type, the 249 // value is converted to an int; otherwise, it is converted to an 250 // unsigned int. These are called the integer promotions. All 251 // other types are unchanged by the integer promotions. 252 QualType PTy = Context.isPromotableBitField(Expr); 253 if (!PTy.isNull()) { 254 ImpCastExprToType(Expr, PTy, CastExpr::CK_IntegralCast); 255 return Expr; 256 } 257 if (Ty->isPromotableIntegerType()) { 258 QualType PT = Context.getPromotedIntegerType(Ty); 259 ImpCastExprToType(Expr, PT, CastExpr::CK_IntegralCast); 260 return Expr; 261 } 262 263 DefaultFunctionArrayLvalueConversion(Expr); 264 return Expr; 265} 266 267/// DefaultArgumentPromotion (C99 6.5.2.2p6). Used for function calls that 268/// do not have a prototype. Arguments that have type float are promoted to 269/// double. All other argument types are converted by UsualUnaryConversions(). 270void Sema::DefaultArgumentPromotion(Expr *&Expr) { 271 QualType Ty = Expr->getType(); 272 assert(!Ty.isNull() && "DefaultArgumentPromotion - missing type"); 273 274 // If this is a 'float' (CVR qualified or typedef) promote to double. 275 if (const BuiltinType *BT = Ty->getAs<BuiltinType>()) 276 if (BT->getKind() == BuiltinType::Float) 277 return ImpCastExprToType(Expr, Context.DoubleTy, 278 CastExpr::CK_FloatingCast); 279 280 UsualUnaryConversions(Expr); 281} 282 283/// DefaultVariadicArgumentPromotion - Like DefaultArgumentPromotion, but 284/// will warn if the resulting type is not a POD type, and rejects ObjC 285/// interfaces passed by value. This returns true if the argument type is 286/// completely illegal. 287bool Sema::DefaultVariadicArgumentPromotion(Expr *&Expr, VariadicCallType CT) { 288 DefaultArgumentPromotion(Expr); 289 290 if (Expr->getType()->isObjCInterfaceType() && 291 DiagRuntimeBehavior(Expr->getLocStart(), 292 PDiag(diag::err_cannot_pass_objc_interface_to_vararg) 293 << Expr->getType() << CT)) 294 return true; 295 296 if (!Expr->getType()->isPODType() && 297 DiagRuntimeBehavior(Expr->getLocStart(), 298 PDiag(diag::warn_cannot_pass_non_pod_arg_to_vararg) 299 << Expr->getType() << CT)) 300 return true; 301 302 return false; 303} 304 305 306/// UsualArithmeticConversions - Performs various conversions that are common to 307/// binary operators (C99 6.3.1.8). If both operands aren't arithmetic, this 308/// routine returns the first non-arithmetic type found. The client is 309/// responsible for emitting appropriate error diagnostics. 310/// FIXME: verify the conversion rules for "complex int" are consistent with 311/// GCC. 312QualType Sema::UsualArithmeticConversions(Expr *&lhsExpr, Expr *&rhsExpr, 313 bool isCompAssign) { 314 if (!isCompAssign) 315 UsualUnaryConversions(lhsExpr); 316 317 UsualUnaryConversions(rhsExpr); 318 319 // For conversion purposes, we ignore any qualifiers. 320 // For example, "const float" and "float" are equivalent. 321 QualType lhs = 322 Context.getCanonicalType(lhsExpr->getType()).getUnqualifiedType(); 323 QualType rhs = 324 Context.getCanonicalType(rhsExpr->getType()).getUnqualifiedType(); 325 326 // If both types are identical, no conversion is needed. 327 if (lhs == rhs) 328 return lhs; 329 330 // If either side is a non-arithmetic type (e.g. a pointer), we are done. 331 // The caller can deal with this (e.g. pointer + int). 332 if (!lhs->isArithmeticType() || !rhs->isArithmeticType()) 333 return lhs; 334 335 // Perform bitfield promotions. 336 QualType LHSBitfieldPromoteTy = Context.isPromotableBitField(lhsExpr); 337 if (!LHSBitfieldPromoteTy.isNull()) 338 lhs = LHSBitfieldPromoteTy; 339 QualType RHSBitfieldPromoteTy = Context.isPromotableBitField(rhsExpr); 340 if (!RHSBitfieldPromoteTy.isNull()) 341 rhs = RHSBitfieldPromoteTy; 342 343 QualType destType = Context.UsualArithmeticConversionsType(lhs, rhs); 344 if (!isCompAssign) 345 ImpCastExprToType(lhsExpr, destType, CastExpr::CK_Unknown); 346 ImpCastExprToType(rhsExpr, destType, CastExpr::CK_Unknown); 347 return destType; 348} 349 350//===----------------------------------------------------------------------===// 351// Semantic Analysis for various Expression Types 352//===----------------------------------------------------------------------===// 353 354 355/// ActOnStringLiteral - The specified tokens were lexed as pasted string 356/// fragments (e.g. "foo" "bar" L"baz"). The result string has to handle string 357/// concatenation ([C99 5.1.1.2, translation phase #6]), so it may come from 358/// multiple tokens. However, the common case is that StringToks points to one 359/// string. 360/// 361Action::OwningExprResult 362Sema::ActOnStringLiteral(const Token *StringToks, unsigned NumStringToks) { 363 assert(NumStringToks && "Must have at least one string!"); 364 365 StringLiteralParser Literal(StringToks, NumStringToks, PP); 366 if (Literal.hadError) 367 return ExprError(); 368 369 llvm::SmallVector<SourceLocation, 4> StringTokLocs; 370 for (unsigned i = 0; i != NumStringToks; ++i) 371 StringTokLocs.push_back(StringToks[i].getLocation()); 372 373 QualType StrTy = Context.CharTy; 374 if (Literal.AnyWide) StrTy = Context.getWCharType(); 375 if (Literal.Pascal) StrTy = Context.UnsignedCharTy; 376 377 // A C++ string literal has a const-qualified element type (C++ 2.13.4p1). 378 if (getLangOptions().CPlusPlus || getLangOptions().ConstStrings ) 379 StrTy.addConst(); 380 381 // Get an array type for the string, according to C99 6.4.5. This includes 382 // the nul terminator character as well as the string length for pascal 383 // strings. 384 StrTy = Context.getConstantArrayType(StrTy, 385 llvm::APInt(32, Literal.GetNumStringChars()+1), 386 ArrayType::Normal, 0); 387 388 // Pass &StringTokLocs[0], StringTokLocs.size() to factory! 389 return Owned(StringLiteral::Create(Context, Literal.GetString(), 390 Literal.GetStringLength(), 391 Literal.AnyWide, StrTy, 392 &StringTokLocs[0], 393 StringTokLocs.size())); 394} 395 396/// ShouldSnapshotBlockValueReference - Return true if a reference inside of 397/// CurBlock to VD should cause it to be snapshotted (as we do for auto 398/// variables defined outside the block) or false if this is not needed (e.g. 399/// for values inside the block or for globals). 400/// 401/// This also keeps the 'hasBlockDeclRefExprs' in the BlockScopeInfo records 402/// up-to-date. 403/// 404static bool ShouldSnapshotBlockValueReference(Sema &S, BlockScopeInfo *CurBlock, 405 ValueDecl *VD) { 406 // If the value is defined inside the block, we couldn't snapshot it even if 407 // we wanted to. 408 if (CurBlock->TheDecl == VD->getDeclContext()) 409 return false; 410 411 // If this is an enum constant or function, it is constant, don't snapshot. 412 if (isa<EnumConstantDecl>(VD) || isa<FunctionDecl>(VD)) 413 return false; 414 415 // If this is a reference to an extern, static, or global variable, no need to 416 // snapshot it. 417 // FIXME: What about 'const' variables in C++? 418 if (const VarDecl *Var = dyn_cast<VarDecl>(VD)) 419 if (!Var->hasLocalStorage()) 420 return false; 421 422 // Blocks that have these can't be constant. 423 CurBlock->hasBlockDeclRefExprs = true; 424 425 // If we have nested blocks, the decl may be declared in an outer block (in 426 // which case that outer block doesn't get "hasBlockDeclRefExprs") or it may 427 // be defined outside all of the current blocks (in which case the blocks do 428 // all get the bit). Walk the nesting chain. 429 for (unsigned I = S.FunctionScopes.size() - 1; I; --I) { 430 BlockScopeInfo *NextBlock = dyn_cast<BlockScopeInfo>(S.FunctionScopes[I]); 431 432 if (!NextBlock) 433 continue; 434 435 // If we found the defining block for the variable, don't mark the block as 436 // having a reference outside it. 437 if (NextBlock->TheDecl == VD->getDeclContext()) 438 break; 439 440 // Otherwise, the DeclRef from the inner block causes the outer one to need 441 // a snapshot as well. 442 NextBlock->hasBlockDeclRefExprs = true; 443 } 444 445 return true; 446} 447 448 449 450/// BuildDeclRefExpr - Build a DeclRefExpr. 451Sema::OwningExprResult 452Sema::BuildDeclRefExpr(ValueDecl *D, QualType Ty, SourceLocation Loc, 453 const CXXScopeSpec *SS) { 454 if (Context.getCanonicalType(Ty) == Context.UndeducedAutoTy) { 455 Diag(Loc, 456 diag::err_auto_variable_cannot_appear_in_own_initializer) 457 << D->getDeclName(); 458 return ExprError(); 459 } 460 461 if (const VarDecl *VD = dyn_cast<VarDecl>(D)) { 462 if (const CXXMethodDecl *MD = dyn_cast<CXXMethodDecl>(CurContext)) { 463 if (const FunctionDecl *FD = MD->getParent()->isLocalClass()) { 464 if (VD->hasLocalStorage() && VD->getDeclContext() != CurContext) { 465 Diag(Loc, diag::err_reference_to_local_var_in_enclosing_function) 466 << D->getIdentifier() << FD->getDeclName(); 467 Diag(D->getLocation(), diag::note_local_variable_declared_here) 468 << D->getIdentifier(); 469 return ExprError(); 470 } 471 } 472 } 473 } 474 475 MarkDeclarationReferenced(Loc, D); 476 477 return Owned(DeclRefExpr::Create(Context, 478 SS? (NestedNameSpecifier *)SS->getScopeRep() : 0, 479 SS? SS->getRange() : SourceRange(), 480 D, Loc, Ty)); 481} 482 483/// getObjectForAnonymousRecordDecl - Retrieve the (unnamed) field or 484/// variable corresponding to the anonymous union or struct whose type 485/// is Record. 486static Decl *getObjectForAnonymousRecordDecl(ASTContext &Context, 487 RecordDecl *Record) { 488 assert(Record->isAnonymousStructOrUnion() && 489 "Record must be an anonymous struct or union!"); 490 491 // FIXME: Once Decls are directly linked together, this will be an O(1) 492 // operation rather than a slow walk through DeclContext's vector (which 493 // itself will be eliminated). DeclGroups might make this even better. 494 DeclContext *Ctx = Record->getDeclContext(); 495 for (DeclContext::decl_iterator D = Ctx->decls_begin(), 496 DEnd = Ctx->decls_end(); 497 D != DEnd; ++D) { 498 if (*D == Record) { 499 // The object for the anonymous struct/union directly 500 // follows its type in the list of declarations. 501 ++D; 502 assert(D != DEnd && "Missing object for anonymous record"); 503 assert(!cast<NamedDecl>(*D)->getDeclName() && "Decl should be unnamed"); 504 return *D; 505 } 506 } 507 508 assert(false && "Missing object for anonymous record"); 509 return 0; 510} 511 512/// \brief Given a field that represents a member of an anonymous 513/// struct/union, build the path from that field's context to the 514/// actual member. 515/// 516/// Construct the sequence of field member references we'll have to 517/// perform to get to the field in the anonymous union/struct. The 518/// list of members is built from the field outward, so traverse it 519/// backwards to go from an object in the current context to the field 520/// we found. 521/// 522/// \returns The variable from which the field access should begin, 523/// for an anonymous struct/union that is not a member of another 524/// class. Otherwise, returns NULL. 525VarDecl *Sema::BuildAnonymousStructUnionMemberPath(FieldDecl *Field, 526 llvm::SmallVectorImpl<FieldDecl *> &Path) { 527 assert(Field->getDeclContext()->isRecord() && 528 cast<RecordDecl>(Field->getDeclContext())->isAnonymousStructOrUnion() 529 && "Field must be stored inside an anonymous struct or union"); 530 531 Path.push_back(Field); 532 VarDecl *BaseObject = 0; 533 DeclContext *Ctx = Field->getDeclContext(); 534 do { 535 RecordDecl *Record = cast<RecordDecl>(Ctx); 536 Decl *AnonObject = getObjectForAnonymousRecordDecl(Context, Record); 537 if (FieldDecl *AnonField = dyn_cast<FieldDecl>(AnonObject)) 538 Path.push_back(AnonField); 539 else { 540 BaseObject = cast<VarDecl>(AnonObject); 541 break; 542 } 543 Ctx = Ctx->getParent(); 544 } while (Ctx->isRecord() && 545 cast<RecordDecl>(Ctx)->isAnonymousStructOrUnion()); 546 547 return BaseObject; 548} 549 550Sema::OwningExprResult 551Sema::BuildAnonymousStructUnionMemberReference(SourceLocation Loc, 552 FieldDecl *Field, 553 Expr *BaseObjectExpr, 554 SourceLocation OpLoc) { 555 llvm::SmallVector<FieldDecl *, 4> AnonFields; 556 VarDecl *BaseObject = BuildAnonymousStructUnionMemberPath(Field, 557 AnonFields); 558 559 // Build the expression that refers to the base object, from 560 // which we will build a sequence of member references to each 561 // of the anonymous union objects and, eventually, the field we 562 // found via name lookup. 563 bool BaseObjectIsPointer = false; 564 Qualifiers BaseQuals; 565 if (BaseObject) { 566 // BaseObject is an anonymous struct/union variable (and is, 567 // therefore, not part of another non-anonymous record). 568 if (BaseObjectExpr) BaseObjectExpr->Destroy(Context); 569 MarkDeclarationReferenced(Loc, BaseObject); 570 BaseObjectExpr = new (Context) DeclRefExpr(BaseObject,BaseObject->getType(), 571 SourceLocation()); 572 BaseQuals 573 = Context.getCanonicalType(BaseObject->getType()).getQualifiers(); 574 } else if (BaseObjectExpr) { 575 // The caller provided the base object expression. Determine 576 // whether its a pointer and whether it adds any qualifiers to the 577 // anonymous struct/union fields we're looking into. 578 QualType ObjectType = BaseObjectExpr->getType(); 579 if (const PointerType *ObjectPtr = ObjectType->getAs<PointerType>()) { 580 BaseObjectIsPointer = true; 581 ObjectType = ObjectPtr->getPointeeType(); 582 } 583 BaseQuals 584 = Context.getCanonicalType(ObjectType).getQualifiers(); 585 } else { 586 // We've found a member of an anonymous struct/union that is 587 // inside a non-anonymous struct/union, so in a well-formed 588 // program our base object expression is "this". 589 if (CXXMethodDecl *MD = dyn_cast<CXXMethodDecl>(CurContext)) { 590 if (!MD->isStatic()) { 591 QualType AnonFieldType 592 = Context.getTagDeclType( 593 cast<RecordDecl>(AnonFields.back()->getDeclContext())); 594 QualType ThisType = Context.getTagDeclType(MD->getParent()); 595 if ((Context.getCanonicalType(AnonFieldType) 596 == Context.getCanonicalType(ThisType)) || 597 IsDerivedFrom(ThisType, AnonFieldType)) { 598 // Our base object expression is "this". 599 BaseObjectExpr = new (Context) CXXThisExpr(Loc, 600 MD->getThisType(Context), 601 /*isImplicit=*/true); 602 BaseObjectIsPointer = true; 603 } 604 } else { 605 return ExprError(Diag(Loc,diag::err_invalid_member_use_in_static_method) 606 << Field->getDeclName()); 607 } 608 BaseQuals = Qualifiers::fromCVRMask(MD->getTypeQualifiers()); 609 } 610 611 if (!BaseObjectExpr) 612 return ExprError(Diag(Loc, diag::err_invalid_non_static_member_use) 613 << Field->getDeclName()); 614 } 615 616 // Build the implicit member references to the field of the 617 // anonymous struct/union. 618 Expr *Result = BaseObjectExpr; 619 Qualifiers ResultQuals = BaseQuals; 620 for (llvm::SmallVector<FieldDecl *, 4>::reverse_iterator 621 FI = AnonFields.rbegin(), FIEnd = AnonFields.rend(); 622 FI != FIEnd; ++FI) { 623 QualType MemberType = (*FI)->getType(); 624 Qualifiers MemberTypeQuals = 625 Context.getCanonicalType(MemberType).getQualifiers(); 626 627 // CVR attributes from the base are picked up by members, 628 // except that 'mutable' members don't pick up 'const'. 629 if ((*FI)->isMutable()) 630 ResultQuals.removeConst(); 631 632 // GC attributes are never picked up by members. 633 ResultQuals.removeObjCGCAttr(); 634 635 // TR 18037 does not allow fields to be declared with address spaces. 636 assert(!MemberTypeQuals.hasAddressSpace()); 637 638 Qualifiers NewQuals = ResultQuals + MemberTypeQuals; 639 if (NewQuals != MemberTypeQuals) 640 MemberType = Context.getQualifiedType(MemberType, NewQuals); 641 642 MarkDeclarationReferenced(Loc, *FI); 643 PerformObjectMemberConversion(Result, /*FIXME:Qualifier=*/0, *FI, *FI); 644 // FIXME: Might this end up being a qualified name? 645 Result = new (Context) MemberExpr(Result, BaseObjectIsPointer, *FI, 646 OpLoc, MemberType); 647 BaseObjectIsPointer = false; 648 ResultQuals = NewQuals; 649 } 650 651 return Owned(Result); 652} 653 654/// Decomposes the given name into a DeclarationName, its location, and 655/// possibly a list of template arguments. 656/// 657/// If this produces template arguments, it is permitted to call 658/// DecomposeTemplateName. 659/// 660/// This actually loses a lot of source location information for 661/// non-standard name kinds; we should consider preserving that in 662/// some way. 663static void DecomposeUnqualifiedId(Sema &SemaRef, 664 const UnqualifiedId &Id, 665 TemplateArgumentListInfo &Buffer, 666 DeclarationName &Name, 667 SourceLocation &NameLoc, 668 const TemplateArgumentListInfo *&TemplateArgs) { 669 if (Id.getKind() == UnqualifiedId::IK_TemplateId) { 670 Buffer.setLAngleLoc(Id.TemplateId->LAngleLoc); 671 Buffer.setRAngleLoc(Id.TemplateId->RAngleLoc); 672 673 ASTTemplateArgsPtr TemplateArgsPtr(SemaRef, 674 Id.TemplateId->getTemplateArgs(), 675 Id.TemplateId->NumArgs); 676 SemaRef.translateTemplateArguments(TemplateArgsPtr, Buffer); 677 TemplateArgsPtr.release(); 678 679 TemplateName TName = 680 Sema::TemplateTy::make(Id.TemplateId->Template).getAsVal<TemplateName>(); 681 682 Name = SemaRef.Context.getNameForTemplate(TName); 683 NameLoc = Id.TemplateId->TemplateNameLoc; 684 TemplateArgs = &Buffer; 685 } else { 686 Name = SemaRef.GetNameFromUnqualifiedId(Id); 687 NameLoc = Id.StartLocation; 688 TemplateArgs = 0; 689 } 690} 691 692/// Decompose the given template name into a list of lookup results. 693/// 694/// The unqualified ID must name a non-dependent template, which can 695/// be more easily tested by checking whether DecomposeUnqualifiedId 696/// found template arguments. 697static void DecomposeTemplateName(LookupResult &R, const UnqualifiedId &Id) { 698 assert(Id.getKind() == UnqualifiedId::IK_TemplateId); 699 TemplateName TName = 700 Sema::TemplateTy::make(Id.TemplateId->Template).getAsVal<TemplateName>(); 701 702 if (TemplateDecl *TD = TName.getAsTemplateDecl()) 703 R.addDecl(TD); 704 else if (OverloadedTemplateStorage *OT = TName.getAsOverloadedTemplate()) 705 for (OverloadedTemplateStorage::iterator I = OT->begin(), E = OT->end(); 706 I != E; ++I) 707 R.addDecl(*I); 708 709 R.resolveKind(); 710} 711 712/// Determines whether the given record is "fully-formed" at the given 713/// location, i.e. whether a qualified lookup into it is assured of 714/// getting consistent results already. 715static bool IsFullyFormedScope(Sema &SemaRef, CXXRecordDecl *Record) { 716 if (!Record->hasDefinition()) 717 return false; 718 719 for (CXXRecordDecl::base_class_iterator I = Record->bases_begin(), 720 E = Record->bases_end(); I != E; ++I) { 721 CanQualType BaseT = SemaRef.Context.getCanonicalType((*I).getType()); 722 CanQual<RecordType> BaseRT = BaseT->getAs<RecordType>(); 723 if (!BaseRT) return false; 724 725 CXXRecordDecl *BaseRecord = cast<CXXRecordDecl>(BaseRT->getDecl()); 726 if (!BaseRecord->hasDefinition() || 727 !IsFullyFormedScope(SemaRef, BaseRecord)) 728 return false; 729 } 730 731 return true; 732} 733 734/// Determines whether we can lookup this id-expression now or whether 735/// we have to wait until template instantiation is complete. 736static bool IsDependentIdExpression(Sema &SemaRef, const CXXScopeSpec &SS) { 737 DeclContext *DC = SemaRef.computeDeclContext(SS, false); 738 739 // If the qualifier scope isn't computable, it's definitely dependent. 740 if (!DC) return true; 741 742 // If the qualifier scope doesn't name a record, we can always look into it. 743 if (!isa<CXXRecordDecl>(DC)) return false; 744 745 // We can't look into record types unless they're fully-formed. 746 if (!IsFullyFormedScope(SemaRef, cast<CXXRecordDecl>(DC))) return true; 747 748 return false; 749} 750 751/// Determines if the given class is provably not derived from all of 752/// the prospective base classes. 753static bool IsProvablyNotDerivedFrom(Sema &SemaRef, 754 CXXRecordDecl *Record, 755 const llvm::SmallPtrSet<CXXRecordDecl*, 4> &Bases) { 756 if (Bases.count(Record->getCanonicalDecl())) 757 return false; 758 759 RecordDecl *RD = Record->getDefinition(); 760 if (!RD) return false; 761 Record = cast<CXXRecordDecl>(RD); 762 763 for (CXXRecordDecl::base_class_iterator I = Record->bases_begin(), 764 E = Record->bases_end(); I != E; ++I) { 765 CanQualType BaseT = SemaRef.Context.getCanonicalType((*I).getType()); 766 CanQual<RecordType> BaseRT = BaseT->getAs<RecordType>(); 767 if (!BaseRT) return false; 768 769 CXXRecordDecl *BaseRecord = cast<CXXRecordDecl>(BaseRT->getDecl()); 770 if (!IsProvablyNotDerivedFrom(SemaRef, BaseRecord, Bases)) 771 return false; 772 } 773 774 return true; 775} 776 777enum IMAKind { 778 /// The reference is definitely not an instance member access. 779 IMA_Static, 780 781 /// The reference may be an implicit instance member access. 782 IMA_Mixed, 783 784 /// The reference may be to an instance member, but it is invalid if 785 /// so, because the context is not an instance method. 786 IMA_Mixed_StaticContext, 787 788 /// The reference may be to an instance member, but it is invalid if 789 /// so, because the context is from an unrelated class. 790 IMA_Mixed_Unrelated, 791 792 /// The reference is definitely an implicit instance member access. 793 IMA_Instance, 794 795 /// The reference may be to an unresolved using declaration. 796 IMA_Unresolved, 797 798 /// The reference may be to an unresolved using declaration and the 799 /// context is not an instance method. 800 IMA_Unresolved_StaticContext, 801 802 /// The reference is to a member of an anonymous structure in a 803 /// non-class context. 804 IMA_AnonymousMember, 805 806 /// All possible referrents are instance members and the current 807 /// context is not an instance method. 808 IMA_Error_StaticContext, 809 810 /// All possible referrents are instance members of an unrelated 811 /// class. 812 IMA_Error_Unrelated 813}; 814 815/// The given lookup names class member(s) and is not being used for 816/// an address-of-member expression. Classify the type of access 817/// according to whether it's possible that this reference names an 818/// instance member. This is best-effort; it is okay to 819/// conservatively answer "yes", in which case some errors will simply 820/// not be caught until template-instantiation. 821static IMAKind ClassifyImplicitMemberAccess(Sema &SemaRef, 822 const LookupResult &R) { 823 assert(!R.empty() && (*R.begin())->isCXXClassMember()); 824 825 bool isStaticContext = 826 (!isa<CXXMethodDecl>(SemaRef.CurContext) || 827 cast<CXXMethodDecl>(SemaRef.CurContext)->isStatic()); 828 829 if (R.isUnresolvableResult()) 830 return isStaticContext ? IMA_Unresolved_StaticContext : IMA_Unresolved; 831 832 // Collect all the declaring classes of instance members we find. 833 bool hasNonInstance = false; 834 llvm::SmallPtrSet<CXXRecordDecl*, 4> Classes; 835 for (LookupResult::iterator I = R.begin(), E = R.end(); I != E; ++I) { 836 NamedDecl *D = *I; 837 if (D->isCXXInstanceMember()) { 838 CXXRecordDecl *R = cast<CXXRecordDecl>(D->getDeclContext()); 839 840 // If this is a member of an anonymous record, move out to the 841 // innermost non-anonymous struct or union. If there isn't one, 842 // that's a special case. 843 while (R->isAnonymousStructOrUnion()) { 844 R = dyn_cast<CXXRecordDecl>(R->getParent()); 845 if (!R) return IMA_AnonymousMember; 846 } 847 Classes.insert(R->getCanonicalDecl()); 848 } 849 else 850 hasNonInstance = true; 851 } 852 853 // If we didn't find any instance members, it can't be an implicit 854 // member reference. 855 if (Classes.empty()) 856 return IMA_Static; 857 858 // If the current context is not an instance method, it can't be 859 // an implicit member reference. 860 if (isStaticContext) 861 return (hasNonInstance ? IMA_Mixed_StaticContext : IMA_Error_StaticContext); 862 863 // If we can prove that the current context is unrelated to all the 864 // declaring classes, it can't be an implicit member reference (in 865 // which case it's an error if any of those members are selected). 866 if (IsProvablyNotDerivedFrom(SemaRef, 867 cast<CXXMethodDecl>(SemaRef.CurContext)->getParent(), 868 Classes)) 869 return (hasNonInstance ? IMA_Mixed_Unrelated : IMA_Error_Unrelated); 870 871 return (hasNonInstance ? IMA_Mixed : IMA_Instance); 872} 873 874/// Diagnose a reference to a field with no object available. 875static void DiagnoseInstanceReference(Sema &SemaRef, 876 const CXXScopeSpec &SS, 877 const LookupResult &R) { 878 SourceLocation Loc = R.getNameLoc(); 879 SourceRange Range(Loc); 880 if (SS.isSet()) Range.setBegin(SS.getRange().getBegin()); 881 882 if (R.getAsSingle<FieldDecl>()) { 883 if (CXXMethodDecl *MD = dyn_cast<CXXMethodDecl>(SemaRef.CurContext)) { 884 if (MD->isStatic()) { 885 // "invalid use of member 'x' in static member function" 886 SemaRef.Diag(Loc, diag::err_invalid_member_use_in_static_method) 887 << Range << R.getLookupName(); 888 return; 889 } 890 } 891 892 SemaRef.Diag(Loc, diag::err_invalid_non_static_member_use) 893 << R.getLookupName() << Range; 894 return; 895 } 896 897 SemaRef.Diag(Loc, diag::err_member_call_without_object) << Range; 898} 899 900/// Diagnose an empty lookup. 901/// 902/// \return false if new lookup candidates were found 903bool Sema::DiagnoseEmptyLookup(Scope *S, CXXScopeSpec &SS, 904 LookupResult &R) { 905 DeclarationName Name = R.getLookupName(); 906 907 unsigned diagnostic = diag::err_undeclared_var_use; 908 unsigned diagnostic_suggest = diag::err_undeclared_var_use_suggest; 909 if (Name.getNameKind() == DeclarationName::CXXOperatorName || 910 Name.getNameKind() == DeclarationName::CXXLiteralOperatorName || 911 Name.getNameKind() == DeclarationName::CXXConversionFunctionName) { 912 diagnostic = diag::err_undeclared_use; 913 diagnostic_suggest = diag::err_undeclared_use_suggest; 914 } 915 916 // If the original lookup was an unqualified lookup, fake an 917 // unqualified lookup. This is useful when (for example) the 918 // original lookup would not have found something because it was a 919 // dependent name. 920 for (DeclContext *DC = SS.isEmpty()? CurContext : 0; 921 DC; DC = DC->getParent()) { 922 if (isa<CXXRecordDecl>(DC)) { 923 LookupQualifiedName(R, DC); 924 925 if (!R.empty()) { 926 // Don't give errors about ambiguities in this lookup. 927 R.suppressDiagnostics(); 928 929 CXXMethodDecl *CurMethod = dyn_cast<CXXMethodDecl>(CurContext); 930 bool isInstance = CurMethod && 931 CurMethod->isInstance() && 932 DC == CurMethod->getParent(); 933 934 // Give a code modification hint to insert 'this->'. 935 // TODO: fixit for inserting 'Base<T>::' in the other cases. 936 // Actually quite difficult! 937 if (isInstance) 938 Diag(R.getNameLoc(), diagnostic) << Name 939 << FixItHint::CreateInsertion(R.getNameLoc(), "this->"); 940 else 941 Diag(R.getNameLoc(), diagnostic) << Name; 942 943 // Do we really want to note all of these? 944 for (LookupResult::iterator I = R.begin(), E = R.end(); I != E; ++I) 945 Diag((*I)->getLocation(), diag::note_dependent_var_use); 946 947 // Tell the callee to try to recover. 948 return false; 949 } 950 } 951 } 952 953 // We didn't find anything, so try to correct for a typo. 954 DeclarationName Corrected; 955 if (S && (Corrected = CorrectTypo(R, S, &SS))) { 956 if (!R.empty()) { 957 if (isa<ValueDecl>(*R.begin()) || isa<FunctionTemplateDecl>(*R.begin())) { 958 if (SS.isEmpty()) 959 Diag(R.getNameLoc(), diagnostic_suggest) << Name << R.getLookupName() 960 << FixItHint::CreateReplacement(R.getNameLoc(), 961 R.getLookupName().getAsString()); 962 else 963 Diag(R.getNameLoc(), diag::err_no_member_suggest) 964 << Name << computeDeclContext(SS, false) << R.getLookupName() 965 << SS.getRange() 966 << FixItHint::CreateReplacement(R.getNameLoc(), 967 R.getLookupName().getAsString()); 968 if (NamedDecl *ND = R.getAsSingle<NamedDecl>()) 969 Diag(ND->getLocation(), diag::note_previous_decl) 970 << ND->getDeclName(); 971 972 // Tell the callee to try to recover. 973 return false; 974 } 975 976 if (isa<TypeDecl>(*R.begin()) || isa<ObjCInterfaceDecl>(*R.begin())) { 977 // FIXME: If we ended up with a typo for a type name or 978 // Objective-C class name, we're in trouble because the parser 979 // is in the wrong place to recover. Suggest the typo 980 // correction, but don't make it a fix-it since we're not going 981 // to recover well anyway. 982 if (SS.isEmpty()) 983 Diag(R.getNameLoc(), diagnostic_suggest) << Name << R.getLookupName(); 984 else 985 Diag(R.getNameLoc(), diag::err_no_member_suggest) 986 << Name << computeDeclContext(SS, false) << R.getLookupName() 987 << SS.getRange(); 988 989 // Don't try to recover; it won't work. 990 return true; 991 } 992 } else { 993 // FIXME: We found a keyword. Suggest it, but don't provide a fix-it 994 // because we aren't able to recover. 995 if (SS.isEmpty()) 996 Diag(R.getNameLoc(), diagnostic_suggest) << Name << Corrected; 997 else 998 Diag(R.getNameLoc(), diag::err_no_member_suggest) 999 << Name << computeDeclContext(SS, false) << Corrected 1000 << SS.getRange(); 1001 return true; 1002 } 1003 R.clear(); 1004 } 1005 1006 // Emit a special diagnostic for failed member lookups. 1007 // FIXME: computing the declaration context might fail here (?) 1008 if (!SS.isEmpty()) { 1009 Diag(R.getNameLoc(), diag::err_no_member) 1010 << Name << computeDeclContext(SS, false) 1011 << SS.getRange(); 1012 return true; 1013 } 1014 1015 // Give up, we can't recover. 1016 Diag(R.getNameLoc(), diagnostic) << Name; 1017 return true; 1018} 1019 1020Sema::OwningExprResult Sema::ActOnIdExpression(Scope *S, 1021 CXXScopeSpec &SS, 1022 UnqualifiedId &Id, 1023 bool HasTrailingLParen, 1024 bool isAddressOfOperand) { 1025 assert(!(isAddressOfOperand && HasTrailingLParen) && 1026 "cannot be direct & operand and have a trailing lparen"); 1027 1028 if (SS.isInvalid()) 1029 return ExprError(); 1030 1031 TemplateArgumentListInfo TemplateArgsBuffer; 1032 1033 // Decompose the UnqualifiedId into the following data. 1034 DeclarationName Name; 1035 SourceLocation NameLoc; 1036 const TemplateArgumentListInfo *TemplateArgs; 1037 DecomposeUnqualifiedId(*this, Id, TemplateArgsBuffer, 1038 Name, NameLoc, TemplateArgs); 1039 1040 IdentifierInfo *II = Name.getAsIdentifierInfo(); 1041 1042 // C++ [temp.dep.expr]p3: 1043 // An id-expression is type-dependent if it contains: 1044 // -- an identifier that was declared with a dependent type, 1045 // (note: handled after lookup) 1046 // -- a template-id that is dependent, 1047 // (note: handled in BuildTemplateIdExpr) 1048 // -- a conversion-function-id that specifies a dependent type, 1049 // -- a nested-name-specifier that contains a class-name that 1050 // names a dependent type. 1051 // Determine whether this is a member of an unknown specialization; 1052 // we need to handle these differently. 1053 if ((Name.getNameKind() == DeclarationName::CXXConversionFunctionName && 1054 Name.getCXXNameType()->isDependentType()) || 1055 (SS.isSet() && IsDependentIdExpression(*this, SS))) { 1056 return ActOnDependentIdExpression(SS, Name, NameLoc, 1057 isAddressOfOperand, 1058 TemplateArgs); 1059 } 1060 1061 // Perform the required lookup. 1062 LookupResult R(*this, Name, NameLoc, LookupOrdinaryName); 1063 if (TemplateArgs) { 1064 // Just re-use the lookup done by isTemplateName. 1065 DecomposeTemplateName(R, Id); 1066 } else { 1067 bool IvarLookupFollowUp = (!SS.isSet() && II && getCurMethodDecl()); 1068 LookupParsedName(R, S, &SS, !IvarLookupFollowUp); 1069 1070 // If this reference is in an Objective-C method, then we need to do 1071 // some special Objective-C lookup, too. 1072 if (IvarLookupFollowUp) { 1073 OwningExprResult E(LookupInObjCMethod(R, S, II, true)); 1074 if (E.isInvalid()) 1075 return ExprError(); 1076 1077 Expr *Ex = E.takeAs<Expr>(); 1078 if (Ex) return Owned(Ex); 1079 } 1080 } 1081 1082 if (R.isAmbiguous()) 1083 return ExprError(); 1084 1085 // Determine whether this name might be a candidate for 1086 // argument-dependent lookup. 1087 bool ADL = UseArgumentDependentLookup(SS, R, HasTrailingLParen); 1088 1089 if (R.empty() && !ADL) { 1090 // Otherwise, this could be an implicitly declared function reference (legal 1091 // in C90, extension in C99, forbidden in C++). 1092 if (HasTrailingLParen && II && !getLangOptions().CPlusPlus) { 1093 NamedDecl *D = ImplicitlyDefineFunction(NameLoc, *II, S); 1094 if (D) R.addDecl(D); 1095 } 1096 1097 // If this name wasn't predeclared and if this is not a function 1098 // call, diagnose the problem. 1099 if (R.empty()) { 1100 if (DiagnoseEmptyLookup(S, SS, R)) 1101 return ExprError(); 1102 1103 assert(!R.empty() && 1104 "DiagnoseEmptyLookup returned false but added no results"); 1105 1106 // If we found an Objective-C instance variable, let 1107 // LookupInObjCMethod build the appropriate expression to 1108 // reference the ivar. 1109 if (ObjCIvarDecl *Ivar = R.getAsSingle<ObjCIvarDecl>()) { 1110 R.clear(); 1111 OwningExprResult E(LookupInObjCMethod(R, S, Ivar->getIdentifier())); 1112 assert(E.isInvalid() || E.get()); 1113 return move(E); 1114 } 1115 } 1116 } 1117 1118 // This is guaranteed from this point on. 1119 assert(!R.empty() || ADL); 1120 1121 if (VarDecl *Var = R.getAsSingle<VarDecl>()) { 1122 // Warn about constructs like: 1123 // if (void *X = foo()) { ... } else { X }. 1124 // In the else block, the pointer is always false. 1125 if (Var->isDeclaredInCondition() && Var->getType()->isScalarType()) { 1126 Scope *CheckS = S; 1127 while (CheckS && CheckS->getControlParent()) { 1128 if ((CheckS->getFlags() & Scope::ElseScope) && 1129 CheckS->getControlParent()->isDeclScope(DeclPtrTy::make(Var))) { 1130 ExprError(Diag(NameLoc, diag::warn_value_always_zero) 1131 << Var->getDeclName() 1132 << (Var->getType()->isPointerType() ? 2 : 1133 Var->getType()->isBooleanType() ? 1 : 0)); 1134 break; 1135 } 1136 1137 // Move to the parent of this scope. 1138 CheckS = CheckS->getParent(); 1139 } 1140 } 1141 } else if (FunctionDecl *Func = R.getAsSingle<FunctionDecl>()) { 1142 if (!getLangOptions().CPlusPlus && !Func->hasPrototype()) { 1143 // C99 DR 316 says that, if a function type comes from a 1144 // function definition (without a prototype), that type is only 1145 // used for checking compatibility. Therefore, when referencing 1146 // the function, we pretend that we don't have the full function 1147 // type. 1148 if (DiagnoseUseOfDecl(Func, NameLoc)) 1149 return ExprError(); 1150 1151 QualType T = Func->getType(); 1152 QualType NoProtoType = T; 1153 if (const FunctionProtoType *Proto = T->getAs<FunctionProtoType>()) 1154 NoProtoType = Context.getFunctionNoProtoType(Proto->getResultType()); 1155 return BuildDeclRefExpr(Func, NoProtoType, NameLoc, &SS); 1156 } 1157 } 1158 1159 // Check whether this might be a C++ implicit instance member access. 1160 // C++ [expr.prim.general]p6: 1161 // Within the definition of a non-static member function, an 1162 // identifier that names a non-static member is transformed to a 1163 // class member access expression. 1164 // But note that &SomeClass::foo is grammatically distinct, even 1165 // though we don't parse it that way. 1166 if (!R.empty() && (*R.begin())->isCXXClassMember()) { 1167 bool isAbstractMemberPointer = (isAddressOfOperand && !SS.isEmpty()); 1168 if (!isAbstractMemberPointer) 1169 return BuildPossibleImplicitMemberExpr(SS, R, TemplateArgs); 1170 } 1171 1172 if (TemplateArgs) 1173 return BuildTemplateIdExpr(SS, R, ADL, *TemplateArgs); 1174 1175 return BuildDeclarationNameExpr(SS, R, ADL); 1176} 1177 1178/// Builds an expression which might be an implicit member expression. 1179Sema::OwningExprResult 1180Sema::BuildPossibleImplicitMemberExpr(const CXXScopeSpec &SS, 1181 LookupResult &R, 1182 const TemplateArgumentListInfo *TemplateArgs) { 1183 switch (ClassifyImplicitMemberAccess(*this, R)) { 1184 case IMA_Instance: 1185 return BuildImplicitMemberExpr(SS, R, TemplateArgs, true); 1186 1187 case IMA_AnonymousMember: 1188 assert(R.isSingleResult()); 1189 return BuildAnonymousStructUnionMemberReference(R.getNameLoc(), 1190 R.getAsSingle<FieldDecl>()); 1191 1192 case IMA_Mixed: 1193 case IMA_Mixed_Unrelated: 1194 case IMA_Unresolved: 1195 return BuildImplicitMemberExpr(SS, R, TemplateArgs, false); 1196 1197 case IMA_Static: 1198 case IMA_Mixed_StaticContext: 1199 case IMA_Unresolved_StaticContext: 1200 if (TemplateArgs) 1201 return BuildTemplateIdExpr(SS, R, false, *TemplateArgs); 1202 return BuildDeclarationNameExpr(SS, R, false); 1203 1204 case IMA_Error_StaticContext: 1205 case IMA_Error_Unrelated: 1206 DiagnoseInstanceReference(*this, SS, R); 1207 return ExprError(); 1208 } 1209 1210 llvm_unreachable("unexpected instance member access kind"); 1211 return ExprError(); 1212} 1213 1214/// BuildQualifiedDeclarationNameExpr - Build a C++ qualified 1215/// declaration name, generally during template instantiation. 1216/// There's a large number of things which don't need to be done along 1217/// this path. 1218Sema::OwningExprResult 1219Sema::BuildQualifiedDeclarationNameExpr(CXXScopeSpec &SS, 1220 DeclarationName Name, 1221 SourceLocation NameLoc) { 1222 DeclContext *DC; 1223 if (!(DC = computeDeclContext(SS, false)) || 1224 DC->isDependentContext() || 1225 RequireCompleteDeclContext(SS)) 1226 return BuildDependentDeclRefExpr(SS, Name, NameLoc, 0); 1227 1228 LookupResult R(*this, Name, NameLoc, LookupOrdinaryName); 1229 LookupQualifiedName(R, DC); 1230 1231 if (R.isAmbiguous()) 1232 return ExprError(); 1233 1234 if (R.empty()) { 1235 Diag(NameLoc, diag::err_no_member) << Name << DC << SS.getRange(); 1236 return ExprError(); 1237 } 1238 1239 return BuildDeclarationNameExpr(SS, R, /*ADL*/ false); 1240} 1241 1242/// LookupInObjCMethod - The parser has read a name in, and Sema has 1243/// detected that we're currently inside an ObjC method. Perform some 1244/// additional lookup. 1245/// 1246/// Ideally, most of this would be done by lookup, but there's 1247/// actually quite a lot of extra work involved. 1248/// 1249/// Returns a null sentinel to indicate trivial success. 1250Sema::OwningExprResult 1251Sema::LookupInObjCMethod(LookupResult &Lookup, Scope *S, 1252 IdentifierInfo *II, bool AllowBuiltinCreation) { 1253 SourceLocation Loc = Lookup.getNameLoc(); 1254 ObjCMethodDecl *CurMethod = getCurMethodDecl(); 1255 1256 // There are two cases to handle here. 1) scoped lookup could have failed, 1257 // in which case we should look for an ivar. 2) scoped lookup could have 1258 // found a decl, but that decl is outside the current instance method (i.e. 1259 // a global variable). In these two cases, we do a lookup for an ivar with 1260 // this name, if the lookup sucedes, we replace it our current decl. 1261 1262 // If we're in a class method, we don't normally want to look for 1263 // ivars. But if we don't find anything else, and there's an 1264 // ivar, that's an error. 1265 bool IsClassMethod = CurMethod->isClassMethod(); 1266 1267 bool LookForIvars; 1268 if (Lookup.empty()) 1269 LookForIvars = true; 1270 else if (IsClassMethod) 1271 LookForIvars = false; 1272 else 1273 LookForIvars = (Lookup.isSingleResult() && 1274 Lookup.getFoundDecl()->isDefinedOutsideFunctionOrMethod()); 1275 ObjCInterfaceDecl *IFace = 0; 1276 if (LookForIvars) { 1277 IFace = CurMethod->getClassInterface(); 1278 ObjCInterfaceDecl *ClassDeclared; 1279 if (ObjCIvarDecl *IV = IFace->lookupInstanceVariable(II, ClassDeclared)) { 1280 // Diagnose using an ivar in a class method. 1281 if (IsClassMethod) 1282 return ExprError(Diag(Loc, diag::error_ivar_use_in_class_method) 1283 << IV->getDeclName()); 1284 1285 // If we're referencing an invalid decl, just return this as a silent 1286 // error node. The error diagnostic was already emitted on the decl. 1287 if (IV->isInvalidDecl()) 1288 return ExprError(); 1289 1290 // Check if referencing a field with __attribute__((deprecated)). 1291 if (DiagnoseUseOfDecl(IV, Loc)) 1292 return ExprError(); 1293 1294 // Diagnose the use of an ivar outside of the declaring class. 1295 if (IV->getAccessControl() == ObjCIvarDecl::Private && 1296 ClassDeclared != IFace) 1297 Diag(Loc, diag::error_private_ivar_access) << IV->getDeclName(); 1298 1299 // FIXME: This should use a new expr for a direct reference, don't 1300 // turn this into Self->ivar, just return a BareIVarExpr or something. 1301 IdentifierInfo &II = Context.Idents.get("self"); 1302 UnqualifiedId SelfName; 1303 SelfName.setIdentifier(&II, SourceLocation()); 1304 CXXScopeSpec SelfScopeSpec; 1305 OwningExprResult SelfExpr = ActOnIdExpression(S, SelfScopeSpec, 1306 SelfName, false, false); 1307 MarkDeclarationReferenced(Loc, IV); 1308 return Owned(new (Context) 1309 ObjCIvarRefExpr(IV, IV->getType(), Loc, 1310 SelfExpr.takeAs<Expr>(), true, true)); 1311 } 1312 } else if (CurMethod->isInstanceMethod()) { 1313 // We should warn if a local variable hides an ivar. 1314 ObjCInterfaceDecl *IFace = CurMethod->getClassInterface(); 1315 ObjCInterfaceDecl *ClassDeclared; 1316 if (ObjCIvarDecl *IV = IFace->lookupInstanceVariable(II, ClassDeclared)) { 1317 if (IV->getAccessControl() != ObjCIvarDecl::Private || 1318 IFace == ClassDeclared) 1319 Diag(Loc, diag::warn_ivar_use_hidden) << IV->getDeclName(); 1320 } 1321 } 1322 1323 if (Lookup.empty() && II && AllowBuiltinCreation) { 1324 // FIXME. Consolidate this with similar code in LookupName. 1325 if (unsigned BuiltinID = II->getBuiltinID()) { 1326 if (!(getLangOptions().CPlusPlus && 1327 Context.BuiltinInfo.isPredefinedLibFunction(BuiltinID))) { 1328 NamedDecl *D = LazilyCreateBuiltin((IdentifierInfo *)II, BuiltinID, 1329 S, Lookup.isForRedeclaration(), 1330 Lookup.getNameLoc()); 1331 if (D) Lookup.addDecl(D); 1332 } 1333 } 1334 } 1335 // Sentinel value saying that we didn't do anything special. 1336 return Owned((Expr*) 0); 1337} 1338 1339/// \brief Cast a base object to a member's actual type. 1340/// 1341/// Logically this happens in three phases: 1342/// 1343/// * First we cast from the base type to the naming class. 1344/// The naming class is the class into which we were looking 1345/// when we found the member; it's the qualifier type if a 1346/// qualifier was provided, and otherwise it's the base type. 1347/// 1348/// * Next we cast from the naming class to the declaring class. 1349/// If the member we found was brought into a class's scope by 1350/// a using declaration, this is that class; otherwise it's 1351/// the class declaring the member. 1352/// 1353/// * Finally we cast from the declaring class to the "true" 1354/// declaring class of the member. This conversion does not 1355/// obey access control. 1356bool 1357Sema::PerformObjectMemberConversion(Expr *&From, 1358 NestedNameSpecifier *Qualifier, 1359 NamedDecl *FoundDecl, 1360 NamedDecl *Member) { 1361 CXXRecordDecl *RD = dyn_cast<CXXRecordDecl>(Member->getDeclContext()); 1362 if (!RD) 1363 return false; 1364 1365 QualType DestRecordType; 1366 QualType DestType; 1367 QualType FromRecordType; 1368 QualType FromType = From->getType(); 1369 bool PointerConversions = false; 1370 if (isa<FieldDecl>(Member)) { 1371 DestRecordType = Context.getCanonicalType(Context.getTypeDeclType(RD)); 1372 1373 if (FromType->getAs<PointerType>()) { 1374 DestType = Context.getPointerType(DestRecordType); 1375 FromRecordType = FromType->getPointeeType(); 1376 PointerConversions = true; 1377 } else { 1378 DestType = DestRecordType; 1379 FromRecordType = FromType; 1380 } 1381 } else if (CXXMethodDecl *Method = dyn_cast<CXXMethodDecl>(Member)) { 1382 if (Method->isStatic()) 1383 return false; 1384 1385 DestType = Method->getThisType(Context); 1386 DestRecordType = DestType->getPointeeType(); 1387 1388 if (FromType->getAs<PointerType>()) { 1389 FromRecordType = FromType->getPointeeType(); 1390 PointerConversions = true; 1391 } else { 1392 FromRecordType = FromType; 1393 DestType = DestRecordType; 1394 } 1395 } else { 1396 // No conversion necessary. 1397 return false; 1398 } 1399 1400 if (DestType->isDependentType() || FromType->isDependentType()) 1401 return false; 1402 1403 // If the unqualified types are the same, no conversion is necessary. 1404 if (Context.hasSameUnqualifiedType(FromRecordType, DestRecordType)) 1405 return false; 1406 1407 SourceRange FromRange = From->getSourceRange(); 1408 SourceLocation FromLoc = FromRange.getBegin(); 1409 1410 // C++ [class.member.lookup]p8: 1411 // [...] Ambiguities can often be resolved by qualifying a name with its 1412 // class name. 1413 // 1414 // If the member was a qualified name and the qualified referred to a 1415 // specific base subobject type, we'll cast to that intermediate type 1416 // first and then to the object in which the member is declared. That allows 1417 // one to resolve ambiguities in, e.g., a diamond-shaped hierarchy such as: 1418 // 1419 // class Base { public: int x; }; 1420 // class Derived1 : public Base { }; 1421 // class Derived2 : public Base { }; 1422 // class VeryDerived : public Derived1, public Derived2 { void f(); }; 1423 // 1424 // void VeryDerived::f() { 1425 // x = 17; // error: ambiguous base subobjects 1426 // Derived1::x = 17; // okay, pick the Base subobject of Derived1 1427 // } 1428 if (Qualifier) { 1429 QualType QType = QualType(Qualifier->getAsType(), 0); 1430 assert(!QType.isNull() && "lookup done with dependent qualifier?"); 1431 assert(QType->isRecordType() && "lookup done with non-record type"); 1432 1433 QualType QRecordType = QualType(QType->getAs<RecordType>(), 0); 1434 1435 // In C++98, the qualifier type doesn't actually have to be a base 1436 // type of the object type, in which case we just ignore it. 1437 // Otherwise build the appropriate casts. 1438 if (IsDerivedFrom(FromRecordType, QRecordType)) { 1439 if (CheckDerivedToBaseConversion(FromRecordType, QRecordType, 1440 FromLoc, FromRange)) 1441 return true; 1442 1443 if (PointerConversions) 1444 QType = Context.getPointerType(QType); 1445 ImpCastExprToType(From, QType, CastExpr::CK_UncheckedDerivedToBase, 1446 /*isLvalue=*/!PointerConversions); 1447 1448 FromType = QType; 1449 FromRecordType = QRecordType; 1450 1451 // If the qualifier type was the same as the destination type, 1452 // we're done. 1453 if (Context.hasSameUnqualifiedType(FromRecordType, DestRecordType)) 1454 return false; 1455 } 1456 } 1457 1458 bool IgnoreAccess = false; 1459 1460 // If we actually found the member through a using declaration, cast 1461 // down to the using declaration's type. 1462 // 1463 // Pointer equality is fine here because only one declaration of a 1464 // class ever has member declarations. 1465 if (FoundDecl->getDeclContext() != Member->getDeclContext()) { 1466 assert(isa<UsingShadowDecl>(FoundDecl)); 1467 QualType URecordType = Context.getTypeDeclType( 1468 cast<CXXRecordDecl>(FoundDecl->getDeclContext())); 1469 1470 // We only need to do this if the naming-class to declaring-class 1471 // conversion is non-trivial. 1472 if (!Context.hasSameUnqualifiedType(FromRecordType, URecordType)) { 1473 assert(IsDerivedFrom(FromRecordType, URecordType)); 1474 if (CheckDerivedToBaseConversion(FromRecordType, URecordType, 1475 FromLoc, FromRange)) 1476 return true; 1477 1478 QualType UType = URecordType; 1479 if (PointerConversions) 1480 UType = Context.getPointerType(UType); 1481 ImpCastExprToType(From, UType, CastExpr::CK_UncheckedDerivedToBase, 1482 /*isLvalue*/ !PointerConversions); 1483 FromType = UType; 1484 FromRecordType = URecordType; 1485 } 1486 1487 // We don't do access control for the conversion from the 1488 // declaring class to the true declaring class. 1489 IgnoreAccess = true; 1490 } 1491 1492 if (CheckDerivedToBaseConversion(FromRecordType, 1493 DestRecordType, 1494 FromLoc, 1495 FromRange, 0, 1496 IgnoreAccess)) 1497 return true; 1498 1499 ImpCastExprToType(From, DestType, CastExpr::CK_UncheckedDerivedToBase, 1500 /*isLvalue=*/!PointerConversions); 1501 return false; 1502} 1503 1504/// \brief Build a MemberExpr AST node. 1505static MemberExpr *BuildMemberExpr(ASTContext &C, Expr *Base, bool isArrow, 1506 const CXXScopeSpec &SS, ValueDecl *Member, 1507 DeclAccessPair FoundDecl, 1508 SourceLocation Loc, QualType Ty, 1509 const TemplateArgumentListInfo *TemplateArgs = 0) { 1510 NestedNameSpecifier *Qualifier = 0; 1511 SourceRange QualifierRange; 1512 if (SS.isSet()) { 1513 Qualifier = (NestedNameSpecifier *) SS.getScopeRep(); 1514 QualifierRange = SS.getRange(); 1515 } 1516 1517 return MemberExpr::Create(C, Base, isArrow, Qualifier, QualifierRange, 1518 Member, FoundDecl, Loc, TemplateArgs, Ty); 1519} 1520 1521/// Builds an implicit member access expression. The current context 1522/// is known to be an instance method, and the given unqualified lookup 1523/// set is known to contain only instance members, at least one of which 1524/// is from an appropriate type. 1525Sema::OwningExprResult 1526Sema::BuildImplicitMemberExpr(const CXXScopeSpec &SS, 1527 LookupResult &R, 1528 const TemplateArgumentListInfo *TemplateArgs, 1529 bool IsKnownInstance) { 1530 assert(!R.empty() && !R.isAmbiguous()); 1531 1532 SourceLocation Loc = R.getNameLoc(); 1533 1534 // We may have found a field within an anonymous union or struct 1535 // (C++ [class.union]). 1536 // FIXME: This needs to happen post-isImplicitMemberReference? 1537 // FIXME: template-ids inside anonymous structs? 1538 if (FieldDecl *FD = R.getAsSingle<FieldDecl>()) 1539 if (cast<RecordDecl>(FD->getDeclContext())->isAnonymousStructOrUnion()) 1540 return BuildAnonymousStructUnionMemberReference(Loc, FD); 1541 1542 // If this is known to be an instance access, go ahead and build a 1543 // 'this' expression now. 1544 QualType ThisType = cast<CXXMethodDecl>(CurContext)->getThisType(Context); 1545 Expr *This = 0; // null signifies implicit access 1546 if (IsKnownInstance) { 1547 SourceLocation Loc = R.getNameLoc(); 1548 if (SS.getRange().isValid()) 1549 Loc = SS.getRange().getBegin(); 1550 This = new (Context) CXXThisExpr(Loc, ThisType, /*isImplicit=*/true); 1551 } 1552 1553 return BuildMemberReferenceExpr(ExprArg(*this, This), ThisType, 1554 /*OpLoc*/ SourceLocation(), 1555 /*IsArrow*/ true, 1556 SS, 1557 /*FirstQualifierInScope*/ 0, 1558 R, TemplateArgs); 1559} 1560 1561bool Sema::UseArgumentDependentLookup(const CXXScopeSpec &SS, 1562 const LookupResult &R, 1563 bool HasTrailingLParen) { 1564 // Only when used directly as the postfix-expression of a call. 1565 if (!HasTrailingLParen) 1566 return false; 1567 1568 // Never if a scope specifier was provided. 1569 if (SS.isSet()) 1570 return false; 1571 1572 // Only in C++ or ObjC++. 1573 if (!getLangOptions().CPlusPlus) 1574 return false; 1575 1576 // Turn off ADL when we find certain kinds of declarations during 1577 // normal lookup: 1578 for (LookupResult::iterator I = R.begin(), E = R.end(); I != E; ++I) { 1579 NamedDecl *D = *I; 1580 1581 // C++0x [basic.lookup.argdep]p3: 1582 // -- a declaration of a class member 1583 // Since using decls preserve this property, we check this on the 1584 // original decl. 1585 if (D->isCXXClassMember()) 1586 return false; 1587 1588 // C++0x [basic.lookup.argdep]p3: 1589 // -- a block-scope function declaration that is not a 1590 // using-declaration 1591 // NOTE: we also trigger this for function templates (in fact, we 1592 // don't check the decl type at all, since all other decl types 1593 // turn off ADL anyway). 1594 if (isa<UsingShadowDecl>(D)) 1595 D = cast<UsingShadowDecl>(D)->getTargetDecl(); 1596 else if (D->getDeclContext()->isFunctionOrMethod()) 1597 return false; 1598 1599 // C++0x [basic.lookup.argdep]p3: 1600 // -- a declaration that is neither a function or a function 1601 // template 1602 // And also for builtin functions. 1603 if (isa<FunctionDecl>(D)) { 1604 FunctionDecl *FDecl = cast<FunctionDecl>(D); 1605 1606 // But also builtin functions. 1607 if (FDecl->getBuiltinID() && FDecl->isImplicit()) 1608 return false; 1609 } else if (!isa<FunctionTemplateDecl>(D)) 1610 return false; 1611 } 1612 1613 return true; 1614} 1615 1616 1617/// Diagnoses obvious problems with the use of the given declaration 1618/// as an expression. This is only actually called for lookups that 1619/// were not overloaded, and it doesn't promise that the declaration 1620/// will in fact be used. 1621static bool CheckDeclInExpr(Sema &S, SourceLocation Loc, NamedDecl *D) { 1622 if (isa<TypedefDecl>(D)) { 1623 S.Diag(Loc, diag::err_unexpected_typedef) << D->getDeclName(); 1624 return true; 1625 } 1626 1627 if (isa<ObjCInterfaceDecl>(D)) { 1628 S.Diag(Loc, diag::err_unexpected_interface) << D->getDeclName(); 1629 return true; 1630 } 1631 1632 if (isa<NamespaceDecl>(D)) { 1633 S.Diag(Loc, diag::err_unexpected_namespace) << D->getDeclName(); 1634 return true; 1635 } 1636 1637 return false; 1638} 1639 1640Sema::OwningExprResult 1641Sema::BuildDeclarationNameExpr(const CXXScopeSpec &SS, 1642 LookupResult &R, 1643 bool NeedsADL) { 1644 // If this is a single, fully-resolved result and we don't need ADL, 1645 // just build an ordinary singleton decl ref. 1646 if (!NeedsADL && R.isSingleResult() && !R.getAsSingle<FunctionTemplateDecl>()) 1647 return BuildDeclarationNameExpr(SS, R.getNameLoc(), R.getFoundDecl()); 1648 1649 // We only need to check the declaration if there's exactly one 1650 // result, because in the overloaded case the results can only be 1651 // functions and function templates. 1652 if (R.isSingleResult() && 1653 CheckDeclInExpr(*this, R.getNameLoc(), R.getFoundDecl())) 1654 return ExprError(); 1655 1656 // Otherwise, just build an unresolved lookup expression. Suppress 1657 // any lookup-related diagnostics; we'll hash these out later, when 1658 // we've picked a target. 1659 R.suppressDiagnostics(); 1660 1661 bool Dependent 1662 = UnresolvedLookupExpr::ComputeDependence(R.begin(), R.end(), 0); 1663 UnresolvedLookupExpr *ULE 1664 = UnresolvedLookupExpr::Create(Context, Dependent, R.getNamingClass(), 1665 (NestedNameSpecifier*) SS.getScopeRep(), 1666 SS.getRange(), 1667 R.getLookupName(), R.getNameLoc(), 1668 NeedsADL, R.isOverloadedResult()); 1669 ULE->addDecls(R.begin(), R.end()); 1670 1671 return Owned(ULE); 1672} 1673 1674 1675/// \brief Complete semantic analysis for a reference to the given declaration. 1676Sema::OwningExprResult 1677Sema::BuildDeclarationNameExpr(const CXXScopeSpec &SS, 1678 SourceLocation Loc, NamedDecl *D) { 1679 assert(D && "Cannot refer to a NULL declaration"); 1680 assert(!isa<FunctionTemplateDecl>(D) && 1681 "Cannot refer unambiguously to a function template"); 1682 1683 if (CheckDeclInExpr(*this, Loc, D)) 1684 return ExprError(); 1685 1686 if (TemplateDecl *Template = dyn_cast<TemplateDecl>(D)) { 1687 // Specifically diagnose references to class templates that are missing 1688 // a template argument list. 1689 Diag(Loc, diag::err_template_decl_ref) 1690 << Template << SS.getRange(); 1691 Diag(Template->getLocation(), diag::note_template_decl_here); 1692 return ExprError(); 1693 } 1694 1695 // Make sure that we're referring to a value. 1696 ValueDecl *VD = dyn_cast<ValueDecl>(D); 1697 if (!VD) { 1698 Diag(Loc, diag::err_ref_non_value) 1699 << D << SS.getRange(); 1700 Diag(D->getLocation(), diag::note_declared_at); 1701 return ExprError(); 1702 } 1703 1704 // Check whether this declaration can be used. Note that we suppress 1705 // this check when we're going to perform argument-dependent lookup 1706 // on this function name, because this might not be the function 1707 // that overload resolution actually selects. 1708 if (DiagnoseUseOfDecl(VD, Loc)) 1709 return ExprError(); 1710 1711 // Only create DeclRefExpr's for valid Decl's. 1712 if (VD->isInvalidDecl()) 1713 return ExprError(); 1714 1715 // If the identifier reference is inside a block, and it refers to a value 1716 // that is outside the block, create a BlockDeclRefExpr instead of a 1717 // DeclRefExpr. This ensures the value is treated as a copy-in snapshot when 1718 // the block is formed. 1719 // 1720 // We do not do this for things like enum constants, global variables, etc, 1721 // as they do not get snapshotted. 1722 // 1723 if (getCurBlock() && 1724 ShouldSnapshotBlockValueReference(*this, getCurBlock(), VD)) { 1725 if (VD->getType().getTypePtr()->isVariablyModifiedType()) { 1726 Diag(Loc, diag::err_ref_vm_type); 1727 Diag(D->getLocation(), diag::note_declared_at); 1728 return ExprError(); 1729 } 1730 1731 if (VD->getType()->isArrayType()) { 1732 Diag(Loc, diag::err_ref_array_type); 1733 Diag(D->getLocation(), diag::note_declared_at); 1734 return ExprError(); 1735 } 1736 1737 MarkDeclarationReferenced(Loc, VD); 1738 QualType ExprTy = VD->getType().getNonReferenceType(); 1739 // The BlocksAttr indicates the variable is bound by-reference. 1740 if (VD->getAttr<BlocksAttr>()) 1741 return Owned(new (Context) BlockDeclRefExpr(VD, ExprTy, Loc, true)); 1742 // This is to record that a 'const' was actually synthesize and added. 1743 bool constAdded = !ExprTy.isConstQualified(); 1744 // Variable will be bound by-copy, make it const within the closure. 1745 1746 ExprTy.addConst(); 1747 return Owned(new (Context) BlockDeclRefExpr(VD, ExprTy, Loc, false, 1748 constAdded)); 1749 } 1750 // If this reference is not in a block or if the referenced variable is 1751 // within the block, create a normal DeclRefExpr. 1752 1753 return BuildDeclRefExpr(VD, VD->getType().getNonReferenceType(), Loc, &SS); 1754} 1755 1756Sema::OwningExprResult Sema::ActOnPredefinedExpr(SourceLocation Loc, 1757 tok::TokenKind Kind) { 1758 PredefinedExpr::IdentType IT; 1759 1760 switch (Kind) { 1761 default: assert(0 && "Unknown simple primary expr!"); 1762 case tok::kw___func__: IT = PredefinedExpr::Func; break; // [C99 6.4.2.2] 1763 case tok::kw___FUNCTION__: IT = PredefinedExpr::Function; break; 1764 case tok::kw___PRETTY_FUNCTION__: IT = PredefinedExpr::PrettyFunction; break; 1765 } 1766 1767 // Pre-defined identifiers are of type char[x], where x is the length of the 1768 // string. 1769 1770 Decl *currentDecl = getCurFunctionOrMethodDecl(); 1771 if (!currentDecl) { 1772 Diag(Loc, diag::ext_predef_outside_function); 1773 currentDecl = Context.getTranslationUnitDecl(); 1774 } 1775 1776 QualType ResTy; 1777 if (cast<DeclContext>(currentDecl)->isDependentContext()) { 1778 ResTy = Context.DependentTy; 1779 } else { 1780 unsigned Length = PredefinedExpr::ComputeName(IT, currentDecl).length(); 1781 1782 llvm::APInt LengthI(32, Length + 1); 1783 ResTy = Context.CharTy.withConst(); 1784 ResTy = Context.getConstantArrayType(ResTy, LengthI, ArrayType::Normal, 0); 1785 } 1786 return Owned(new (Context) PredefinedExpr(Loc, ResTy, IT)); 1787} 1788 1789Sema::OwningExprResult Sema::ActOnCharacterConstant(const Token &Tok) { 1790 llvm::SmallString<16> CharBuffer; 1791 bool Invalid = false; 1792 llvm::StringRef ThisTok = PP.getSpelling(Tok, CharBuffer, &Invalid); 1793 if (Invalid) 1794 return ExprError(); 1795 1796 CharLiteralParser Literal(ThisTok.begin(), ThisTok.end(), Tok.getLocation(), 1797 PP); 1798 if (Literal.hadError()) 1799 return ExprError(); 1800 1801 QualType Ty; 1802 if (!getLangOptions().CPlusPlus) 1803 Ty = Context.IntTy; // 'x' and L'x' -> int in C. 1804 else if (Literal.isWide()) 1805 Ty = Context.WCharTy; // L'x' -> wchar_t in C++. 1806 else if (Literal.isMultiChar()) 1807 Ty = Context.IntTy; // 'wxyz' -> int in C++. 1808 else 1809 Ty = Context.CharTy; // 'x' -> char in C++ 1810 1811 return Owned(new (Context) CharacterLiteral(Literal.getValue(), 1812 Literal.isWide(), 1813 Ty, Tok.getLocation())); 1814} 1815 1816Action::OwningExprResult Sema::ActOnNumericConstant(const Token &Tok) { 1817 // Fast path for a single digit (which is quite common). A single digit 1818 // cannot have a trigraph, escaped newline, radix prefix, or type suffix. 1819 if (Tok.getLength() == 1) { 1820 const char Val = PP.getSpellingOfSingleCharacterNumericConstant(Tok); 1821 unsigned IntSize = Context.Target.getIntWidth(); 1822 return Owned(new (Context) IntegerLiteral(llvm::APInt(IntSize, Val-'0'), 1823 Context.IntTy, Tok.getLocation())); 1824 } 1825 1826 llvm::SmallString<512> IntegerBuffer; 1827 // Add padding so that NumericLiteralParser can overread by one character. 1828 IntegerBuffer.resize(Tok.getLength()+1); 1829 const char *ThisTokBegin = &IntegerBuffer[0]; 1830 1831 // Get the spelling of the token, which eliminates trigraphs, etc. 1832 bool Invalid = false; 1833 unsigned ActualLength = PP.getSpelling(Tok, ThisTokBegin, &Invalid); 1834 if (Invalid) 1835 return ExprError(); 1836 1837 NumericLiteralParser Literal(ThisTokBegin, ThisTokBegin+ActualLength, 1838 Tok.getLocation(), PP); 1839 if (Literal.hadError) 1840 return ExprError(); 1841 1842 Expr *Res; 1843 1844 if (Literal.isFloatingLiteral()) { 1845 QualType Ty; 1846 if (Literal.isFloat) 1847 Ty = Context.FloatTy; 1848 else if (!Literal.isLong) 1849 Ty = Context.DoubleTy; 1850 else 1851 Ty = Context.LongDoubleTy; 1852 1853 const llvm::fltSemantics &Format = Context.getFloatTypeSemantics(Ty); 1854 1855 using llvm::APFloat; 1856 APFloat Val(Format); 1857 1858 APFloat::opStatus result = Literal.GetFloatValue(Val); 1859 1860 // Overflow is always an error, but underflow is only an error if 1861 // we underflowed to zero (APFloat reports denormals as underflow). 1862 if ((result & APFloat::opOverflow) || 1863 ((result & APFloat::opUnderflow) && Val.isZero())) { 1864 unsigned diagnostic; 1865 llvm::SmallString<20> buffer; 1866 if (result & APFloat::opOverflow) { 1867 diagnostic = diag::warn_float_overflow; 1868 APFloat::getLargest(Format).toString(buffer); 1869 } else { 1870 diagnostic = diag::warn_float_underflow; 1871 APFloat::getSmallest(Format).toString(buffer); 1872 } 1873 1874 Diag(Tok.getLocation(), diagnostic) 1875 << Ty 1876 << llvm::StringRef(buffer.data(), buffer.size()); 1877 } 1878 1879 bool isExact = (result == APFloat::opOK); 1880 Res = new (Context) FloatingLiteral(Val, isExact, Ty, Tok.getLocation()); 1881 1882 } else if (!Literal.isIntegerLiteral()) { 1883 return ExprError(); 1884 } else { 1885 QualType Ty; 1886 1887 // long long is a C99 feature. 1888 if (!getLangOptions().C99 && !getLangOptions().CPlusPlus0x && 1889 Literal.isLongLong) 1890 Diag(Tok.getLocation(), diag::ext_longlong); 1891 1892 // Get the value in the widest-possible width. 1893 llvm::APInt ResultVal(Context.Target.getIntMaxTWidth(), 0); 1894 1895 if (Literal.GetIntegerValue(ResultVal)) { 1896 // If this value didn't fit into uintmax_t, warn and force to ull. 1897 Diag(Tok.getLocation(), diag::warn_integer_too_large); 1898 Ty = Context.UnsignedLongLongTy; 1899 assert(Context.getTypeSize(Ty) == ResultVal.getBitWidth() && 1900 "long long is not intmax_t?"); 1901 } else { 1902 // If this value fits into a ULL, try to figure out what else it fits into 1903 // according to the rules of C99 6.4.4.1p5. 1904 1905 // Octal, Hexadecimal, and integers with a U suffix are allowed to 1906 // be an unsigned int. 1907 bool AllowUnsigned = Literal.isUnsigned || Literal.getRadix() != 10; 1908 1909 // Check from smallest to largest, picking the smallest type we can. 1910 unsigned Width = 0; 1911 if (!Literal.isLong && !Literal.isLongLong) { 1912 // Are int/unsigned possibilities? 1913 unsigned IntSize = Context.Target.getIntWidth(); 1914 1915 // Does it fit in a unsigned int? 1916 if (ResultVal.isIntN(IntSize)) { 1917 // Does it fit in a signed int? 1918 if (!Literal.isUnsigned && ResultVal[IntSize-1] == 0) 1919 Ty = Context.IntTy; 1920 else if (AllowUnsigned) 1921 Ty = Context.UnsignedIntTy; 1922 Width = IntSize; 1923 } 1924 } 1925 1926 // Are long/unsigned long possibilities? 1927 if (Ty.isNull() && !Literal.isLongLong) { 1928 unsigned LongSize = Context.Target.getLongWidth(); 1929 1930 // Does it fit in a unsigned long? 1931 if (ResultVal.isIntN(LongSize)) { 1932 // Does it fit in a signed long? 1933 if (!Literal.isUnsigned && ResultVal[LongSize-1] == 0) 1934 Ty = Context.LongTy; 1935 else if (AllowUnsigned) 1936 Ty = Context.UnsignedLongTy; 1937 Width = LongSize; 1938 } 1939 } 1940 1941 // Finally, check long long if needed. 1942 if (Ty.isNull()) { 1943 unsigned LongLongSize = Context.Target.getLongLongWidth(); 1944 1945 // Does it fit in a unsigned long long? 1946 if (ResultVal.isIntN(LongLongSize)) { 1947 // Does it fit in a signed long long? 1948 if (!Literal.isUnsigned && ResultVal[LongLongSize-1] == 0) 1949 Ty = Context.LongLongTy; 1950 else if (AllowUnsigned) 1951 Ty = Context.UnsignedLongLongTy; 1952 Width = LongLongSize; 1953 } 1954 } 1955 1956 // If we still couldn't decide a type, we probably have something that 1957 // does not fit in a signed long long, but has no U suffix. 1958 if (Ty.isNull()) { 1959 Diag(Tok.getLocation(), diag::warn_integer_too_large_for_signed); 1960 Ty = Context.UnsignedLongLongTy; 1961 Width = Context.Target.getLongLongWidth(); 1962 } 1963 1964 if (ResultVal.getBitWidth() != Width) 1965 ResultVal.trunc(Width); 1966 } 1967 Res = new (Context) IntegerLiteral(ResultVal, Ty, Tok.getLocation()); 1968 } 1969 1970 // If this is an imaginary literal, create the ImaginaryLiteral wrapper. 1971 if (Literal.isImaginary) 1972 Res = new (Context) ImaginaryLiteral(Res, 1973 Context.getComplexType(Res->getType())); 1974 1975 return Owned(Res); 1976} 1977 1978Action::OwningExprResult Sema::ActOnParenExpr(SourceLocation L, 1979 SourceLocation R, ExprArg Val) { 1980 Expr *E = Val.takeAs<Expr>(); 1981 assert((E != 0) && "ActOnParenExpr() missing expr"); 1982 return Owned(new (Context) ParenExpr(L, R, E)); 1983} 1984 1985/// The UsualUnaryConversions() function is *not* called by this routine. 1986/// See C99 6.3.2.1p[2-4] for more details. 1987bool Sema::CheckSizeOfAlignOfOperand(QualType exprType, 1988 SourceLocation OpLoc, 1989 const SourceRange &ExprRange, 1990 bool isSizeof) { 1991 if (exprType->isDependentType()) 1992 return false; 1993 1994 // C++ [expr.sizeof]p2: "When applied to a reference or a reference type, 1995 // the result is the size of the referenced type." 1996 // C++ [expr.alignof]p3: "When alignof is applied to a reference type, the 1997 // result shall be the alignment of the referenced type." 1998 if (const ReferenceType *Ref = exprType->getAs<ReferenceType>()) 1999 exprType = Ref->getPointeeType(); 2000 2001 // C99 6.5.3.4p1: 2002 if (exprType->isFunctionType()) { 2003 // alignof(function) is allowed as an extension. 2004 if (isSizeof) 2005 Diag(OpLoc, diag::ext_sizeof_function_type) << ExprRange; 2006 return false; 2007 } 2008 2009 // Allow sizeof(void)/alignof(void) as an extension. 2010 if (exprType->isVoidType()) { 2011 Diag(OpLoc, diag::ext_sizeof_void_type) 2012 << (isSizeof ? "sizeof" : "__alignof") << ExprRange; 2013 return false; 2014 } 2015 2016 if (RequireCompleteType(OpLoc, exprType, 2017 PDiag(diag::err_sizeof_alignof_incomplete_type) 2018 << int(!isSizeof) << ExprRange)) 2019 return true; 2020 2021 // Reject sizeof(interface) and sizeof(interface<proto>) in 64-bit mode. 2022 if (LangOpts.ObjCNonFragileABI && exprType->isObjCInterfaceType()) { 2023 Diag(OpLoc, diag::err_sizeof_nonfragile_interface) 2024 << exprType << isSizeof << ExprRange; 2025 return true; 2026 } 2027 2028 return false; 2029} 2030 2031bool Sema::CheckAlignOfExpr(Expr *E, SourceLocation OpLoc, 2032 const SourceRange &ExprRange) { 2033 E = E->IgnoreParens(); 2034 2035 // alignof decl is always ok. 2036 if (isa<DeclRefExpr>(E)) 2037 return false; 2038 2039 // Cannot know anything else if the expression is dependent. 2040 if (E->isTypeDependent()) 2041 return false; 2042 2043 if (E->getBitField()) { 2044 Diag(OpLoc, diag::err_sizeof_alignof_bitfield) << 1 << ExprRange; 2045 return true; 2046 } 2047 2048 // Alignment of a field access is always okay, so long as it isn't a 2049 // bit-field. 2050 if (MemberExpr *ME = dyn_cast<MemberExpr>(E)) 2051 if (isa<FieldDecl>(ME->getMemberDecl())) 2052 return false; 2053 2054 return CheckSizeOfAlignOfOperand(E->getType(), OpLoc, ExprRange, false); 2055} 2056 2057/// \brief Build a sizeof or alignof expression given a type operand. 2058Action::OwningExprResult 2059Sema::CreateSizeOfAlignOfExpr(TypeSourceInfo *TInfo, 2060 SourceLocation OpLoc, 2061 bool isSizeOf, SourceRange R) { 2062 if (!TInfo) 2063 return ExprError(); 2064 2065 QualType T = TInfo->getType(); 2066 2067 if (!T->isDependentType() && 2068 CheckSizeOfAlignOfOperand(T, OpLoc, R, isSizeOf)) 2069 return ExprError(); 2070 2071 // C99 6.5.3.4p4: the type (an unsigned integer type) is size_t. 2072 return Owned(new (Context) SizeOfAlignOfExpr(isSizeOf, TInfo, 2073 Context.getSizeType(), OpLoc, 2074 R.getEnd())); 2075} 2076 2077/// \brief Build a sizeof or alignof expression given an expression 2078/// operand. 2079Action::OwningExprResult 2080Sema::CreateSizeOfAlignOfExpr(Expr *E, SourceLocation OpLoc, 2081 bool isSizeOf, SourceRange R) { 2082 // Verify that the operand is valid. 2083 bool isInvalid = false; 2084 if (E->isTypeDependent()) { 2085 // Delay type-checking for type-dependent expressions. 2086 } else if (!isSizeOf) { 2087 isInvalid = CheckAlignOfExpr(E, OpLoc, R); 2088 } else if (E->getBitField()) { // C99 6.5.3.4p1. 2089 Diag(OpLoc, diag::err_sizeof_alignof_bitfield) << 0; 2090 isInvalid = true; 2091 } else { 2092 isInvalid = CheckSizeOfAlignOfOperand(E->getType(), OpLoc, R, true); 2093 } 2094 2095 if (isInvalid) 2096 return ExprError(); 2097 2098 // C99 6.5.3.4p4: the type (an unsigned integer type) is size_t. 2099 return Owned(new (Context) SizeOfAlignOfExpr(isSizeOf, E, 2100 Context.getSizeType(), OpLoc, 2101 R.getEnd())); 2102} 2103 2104/// ActOnSizeOfAlignOfExpr - Handle @c sizeof(type) and @c sizeof @c expr and 2105/// the same for @c alignof and @c __alignof 2106/// Note that the ArgRange is invalid if isType is false. 2107Action::OwningExprResult 2108Sema::ActOnSizeOfAlignOfExpr(SourceLocation OpLoc, bool isSizeof, bool isType, 2109 void *TyOrEx, const SourceRange &ArgRange) { 2110 // If error parsing type, ignore. 2111 if (TyOrEx == 0) return ExprError(); 2112 2113 if (isType) { 2114 TypeSourceInfo *TInfo; 2115 (void) GetTypeFromParser(TyOrEx, &TInfo); 2116 return CreateSizeOfAlignOfExpr(TInfo, OpLoc, isSizeof, ArgRange); 2117 } 2118 2119 Expr *ArgEx = (Expr *)TyOrEx; 2120 Action::OwningExprResult Result 2121 = CreateSizeOfAlignOfExpr(ArgEx, OpLoc, isSizeof, ArgEx->getSourceRange()); 2122 2123 if (Result.isInvalid()) 2124 DeleteExpr(ArgEx); 2125 2126 return move(Result); 2127} 2128 2129QualType Sema::CheckRealImagOperand(Expr *&V, SourceLocation Loc, bool isReal) { 2130 if (V->isTypeDependent()) 2131 return Context.DependentTy; 2132 2133 // These operators return the element type of a complex type. 2134 if (const ComplexType *CT = V->getType()->getAs<ComplexType>()) 2135 return CT->getElementType(); 2136 2137 // Otherwise they pass through real integer and floating point types here. 2138 if (V->getType()->isArithmeticType()) 2139 return V->getType(); 2140 2141 // Reject anything else. 2142 Diag(Loc, diag::err_realimag_invalid_type) << V->getType() 2143 << (isReal ? "__real" : "__imag"); 2144 return QualType(); 2145} 2146 2147 2148 2149Action::OwningExprResult 2150Sema::ActOnPostfixUnaryOp(Scope *S, SourceLocation OpLoc, 2151 tok::TokenKind Kind, ExprArg Input) { 2152 UnaryOperator::Opcode Opc; 2153 switch (Kind) { 2154 default: assert(0 && "Unknown unary op!"); 2155 case tok::plusplus: Opc = UnaryOperator::PostInc; break; 2156 case tok::minusminus: Opc = UnaryOperator::PostDec; break; 2157 } 2158 2159 return BuildUnaryOp(S, OpLoc, Opc, move(Input)); 2160} 2161 2162Action::OwningExprResult 2163Sema::ActOnArraySubscriptExpr(Scope *S, ExprArg Base, SourceLocation LLoc, 2164 ExprArg Idx, SourceLocation RLoc) { 2165 // Since this might be a postfix expression, get rid of ParenListExprs. 2166 Base = MaybeConvertParenListExprToParenExpr(S, move(Base)); 2167 2168 Expr *LHSExp = static_cast<Expr*>(Base.get()), 2169 *RHSExp = static_cast<Expr*>(Idx.get()); 2170 2171 if (getLangOptions().CPlusPlus && 2172 (LHSExp->isTypeDependent() || RHSExp->isTypeDependent())) { 2173 Base.release(); 2174 Idx.release(); 2175 return Owned(new (Context) ArraySubscriptExpr(LHSExp, RHSExp, 2176 Context.DependentTy, RLoc)); 2177 } 2178 2179 if (getLangOptions().CPlusPlus && 2180 (LHSExp->getType()->isRecordType() || 2181 LHSExp->getType()->isEnumeralType() || 2182 RHSExp->getType()->isRecordType() || 2183 RHSExp->getType()->isEnumeralType())) { 2184 return CreateOverloadedArraySubscriptExpr(LLoc, RLoc, move(Base),move(Idx)); 2185 } 2186 2187 return CreateBuiltinArraySubscriptExpr(move(Base), LLoc, move(Idx), RLoc); 2188} 2189 2190 2191Action::OwningExprResult 2192Sema::CreateBuiltinArraySubscriptExpr(ExprArg Base, SourceLocation LLoc, 2193 ExprArg Idx, SourceLocation RLoc) { 2194 Expr *LHSExp = static_cast<Expr*>(Base.get()); 2195 Expr *RHSExp = static_cast<Expr*>(Idx.get()); 2196 2197 // Perform default conversions. 2198 if (!LHSExp->getType()->getAs<VectorType>()) 2199 DefaultFunctionArrayLvalueConversion(LHSExp); 2200 DefaultFunctionArrayLvalueConversion(RHSExp); 2201 2202 QualType LHSTy = LHSExp->getType(), RHSTy = RHSExp->getType(); 2203 2204 // C99 6.5.2.1p2: the expression e1[e2] is by definition precisely equivalent 2205 // to the expression *((e1)+(e2)). This means the array "Base" may actually be 2206 // in the subscript position. As a result, we need to derive the array base 2207 // and index from the expression types. 2208 Expr *BaseExpr, *IndexExpr; 2209 QualType ResultType; 2210 if (LHSTy->isDependentType() || RHSTy->isDependentType()) { 2211 BaseExpr = LHSExp; 2212 IndexExpr = RHSExp; 2213 ResultType = Context.DependentTy; 2214 } else if (const PointerType *PTy = LHSTy->getAs<PointerType>()) { 2215 BaseExpr = LHSExp; 2216 IndexExpr = RHSExp; 2217 ResultType = PTy->getPointeeType(); 2218 } else if (const PointerType *PTy = RHSTy->getAs<PointerType>()) { 2219 // Handle the uncommon case of "123[Ptr]". 2220 BaseExpr = RHSExp; 2221 IndexExpr = LHSExp; 2222 ResultType = PTy->getPointeeType(); 2223 } else if (const ObjCObjectPointerType *PTy = 2224 LHSTy->getAs<ObjCObjectPointerType>()) { 2225 BaseExpr = LHSExp; 2226 IndexExpr = RHSExp; 2227 ResultType = PTy->getPointeeType(); 2228 } else if (const ObjCObjectPointerType *PTy = 2229 RHSTy->getAs<ObjCObjectPointerType>()) { 2230 // Handle the uncommon case of "123[Ptr]". 2231 BaseExpr = RHSExp; 2232 IndexExpr = LHSExp; 2233 ResultType = PTy->getPointeeType(); 2234 } else if (const VectorType *VTy = LHSTy->getAs<VectorType>()) { 2235 BaseExpr = LHSExp; // vectors: V[123] 2236 IndexExpr = RHSExp; 2237 2238 // FIXME: need to deal with const... 2239 ResultType = VTy->getElementType(); 2240 } else if (LHSTy->isArrayType()) { 2241 // If we see an array that wasn't promoted by 2242 // DefaultFunctionArrayLvalueConversion, it must be an array that 2243 // wasn't promoted because of the C90 rule that doesn't 2244 // allow promoting non-lvalue arrays. Warn, then 2245 // force the promotion here. 2246 Diag(LHSExp->getLocStart(), diag::ext_subscript_non_lvalue) << 2247 LHSExp->getSourceRange(); 2248 ImpCastExprToType(LHSExp, Context.getArrayDecayedType(LHSTy), 2249 CastExpr::CK_ArrayToPointerDecay); 2250 LHSTy = LHSExp->getType(); 2251 2252 BaseExpr = LHSExp; 2253 IndexExpr = RHSExp; 2254 ResultType = LHSTy->getAs<PointerType>()->getPointeeType(); 2255 } else if (RHSTy->isArrayType()) { 2256 // Same as previous, except for 123[f().a] case 2257 Diag(RHSExp->getLocStart(), diag::ext_subscript_non_lvalue) << 2258 RHSExp->getSourceRange(); 2259 ImpCastExprToType(RHSExp, Context.getArrayDecayedType(RHSTy), 2260 CastExpr::CK_ArrayToPointerDecay); 2261 RHSTy = RHSExp->getType(); 2262 2263 BaseExpr = RHSExp; 2264 IndexExpr = LHSExp; 2265 ResultType = RHSTy->getAs<PointerType>()->getPointeeType(); 2266 } else { 2267 return ExprError(Diag(LLoc, diag::err_typecheck_subscript_value) 2268 << LHSExp->getSourceRange() << RHSExp->getSourceRange()); 2269 } 2270 // C99 6.5.2.1p1 2271 if (!(IndexExpr->getType()->isIntegerType() && 2272 IndexExpr->getType()->isScalarType()) && !IndexExpr->isTypeDependent()) 2273 return ExprError(Diag(LLoc, diag::err_typecheck_subscript_not_integer) 2274 << IndexExpr->getSourceRange()); 2275 2276 if ((IndexExpr->getType()->isSpecificBuiltinType(BuiltinType::Char_S) || 2277 IndexExpr->getType()->isSpecificBuiltinType(BuiltinType::Char_U)) 2278 && !IndexExpr->isTypeDependent()) 2279 Diag(LLoc, diag::warn_subscript_is_char) << IndexExpr->getSourceRange(); 2280 2281 // C99 6.5.2.1p1: "shall have type "pointer to *object* type". Similarly, 2282 // C++ [expr.sub]p1: The type "T" shall be a completely-defined object 2283 // type. Note that Functions are not objects, and that (in C99 parlance) 2284 // incomplete types are not object types. 2285 if (ResultType->isFunctionType()) { 2286 Diag(BaseExpr->getLocStart(), diag::err_subscript_function_type) 2287 << ResultType << BaseExpr->getSourceRange(); 2288 return ExprError(); 2289 } 2290 2291 if (!ResultType->isDependentType() && 2292 RequireCompleteType(LLoc, ResultType, 2293 PDiag(diag::err_subscript_incomplete_type) 2294 << BaseExpr->getSourceRange())) 2295 return ExprError(); 2296 2297 // Diagnose bad cases where we step over interface counts. 2298 if (ResultType->isObjCInterfaceType() && LangOpts.ObjCNonFragileABI) { 2299 Diag(LLoc, diag::err_subscript_nonfragile_interface) 2300 << ResultType << BaseExpr->getSourceRange(); 2301 return ExprError(); 2302 } 2303 2304 Base.release(); 2305 Idx.release(); 2306 return Owned(new (Context) ArraySubscriptExpr(LHSExp, RHSExp, 2307 ResultType, RLoc)); 2308} 2309 2310QualType Sema:: 2311CheckExtVectorComponent(QualType baseType, SourceLocation OpLoc, 2312 const IdentifierInfo *CompName, 2313 SourceLocation CompLoc) { 2314 // FIXME: Share logic with ExtVectorElementExpr::containsDuplicateElements, 2315 // see FIXME there. 2316 // 2317 // FIXME: This logic can be greatly simplified by splitting it along 2318 // halving/not halving and reworking the component checking. 2319 const ExtVectorType *vecType = baseType->getAs<ExtVectorType>(); 2320 2321 // The vector accessor can't exceed the number of elements. 2322 const char *compStr = CompName->getNameStart(); 2323 2324 // This flag determines whether or not the component is one of the four 2325 // special names that indicate a subset of exactly half the elements are 2326 // to be selected. 2327 bool HalvingSwizzle = false; 2328 2329 // This flag determines whether or not CompName has an 's' char prefix, 2330 // indicating that it is a string of hex values to be used as vector indices. 2331 bool HexSwizzle = *compStr == 's' || *compStr == 'S'; 2332 2333 // Check that we've found one of the special components, or that the component 2334 // names must come from the same set. 2335 if (!strcmp(compStr, "hi") || !strcmp(compStr, "lo") || 2336 !strcmp(compStr, "even") || !strcmp(compStr, "odd")) { 2337 HalvingSwizzle = true; 2338 } else if (vecType->getPointAccessorIdx(*compStr) != -1) { 2339 do 2340 compStr++; 2341 while (*compStr && vecType->getPointAccessorIdx(*compStr) != -1); 2342 } else if (HexSwizzle || vecType->getNumericAccessorIdx(*compStr) != -1) { 2343 do 2344 compStr++; 2345 while (*compStr && vecType->getNumericAccessorIdx(*compStr) != -1); 2346 } 2347 2348 if (!HalvingSwizzle && *compStr) { 2349 // We didn't get to the end of the string. This means the component names 2350 // didn't come from the same set *or* we encountered an illegal name. 2351 Diag(OpLoc, diag::err_ext_vector_component_name_illegal) 2352 << std::string(compStr,compStr+1) << SourceRange(CompLoc); 2353 return QualType(); 2354 } 2355 2356 // Ensure no component accessor exceeds the width of the vector type it 2357 // operates on. 2358 if (!HalvingSwizzle) { 2359 compStr = CompName->getNameStart(); 2360 2361 if (HexSwizzle) 2362 compStr++; 2363 2364 while (*compStr) { 2365 if (!vecType->isAccessorWithinNumElements(*compStr++)) { 2366 Diag(OpLoc, diag::err_ext_vector_component_exceeds_length) 2367 << baseType << SourceRange(CompLoc); 2368 return QualType(); 2369 } 2370 } 2371 } 2372 2373 // The component accessor looks fine - now we need to compute the actual type. 2374 // The vector type is implied by the component accessor. For example, 2375 // vec4.b is a float, vec4.xy is a vec2, vec4.rgb is a vec3, etc. 2376 // vec4.s0 is a float, vec4.s23 is a vec3, etc. 2377 // vec4.hi, vec4.lo, vec4.e, and vec4.o all return vec2. 2378 unsigned CompSize = HalvingSwizzle ? (vecType->getNumElements() + 1) / 2 2379 : CompName->getLength(); 2380 if (HexSwizzle) 2381 CompSize--; 2382 2383 if (CompSize == 1) 2384 return vecType->getElementType(); 2385 2386 QualType VT = Context.getExtVectorType(vecType->getElementType(), CompSize); 2387 // Now look up the TypeDefDecl from the vector type. Without this, 2388 // diagostics look bad. We want extended vector types to appear built-in. 2389 for (unsigned i = 0, E = ExtVectorDecls.size(); i != E; ++i) { 2390 if (ExtVectorDecls[i]->getUnderlyingType() == VT) 2391 return Context.getTypedefType(ExtVectorDecls[i]); 2392 } 2393 return VT; // should never get here (a typedef type should always be found). 2394} 2395 2396static Decl *FindGetterNameDeclFromProtocolList(const ObjCProtocolDecl*PDecl, 2397 IdentifierInfo *Member, 2398 const Selector &Sel, 2399 ASTContext &Context) { 2400 2401 if (ObjCPropertyDecl *PD = PDecl->FindPropertyDeclaration(Member)) 2402 return PD; 2403 if (ObjCMethodDecl *OMD = PDecl->getInstanceMethod(Sel)) 2404 return OMD; 2405 2406 for (ObjCProtocolDecl::protocol_iterator I = PDecl->protocol_begin(), 2407 E = PDecl->protocol_end(); I != E; ++I) { 2408 if (Decl *D = FindGetterNameDeclFromProtocolList(*I, Member, Sel, 2409 Context)) 2410 return D; 2411 } 2412 return 0; 2413} 2414 2415static Decl *FindGetterNameDecl(const ObjCObjectPointerType *QIdTy, 2416 IdentifierInfo *Member, 2417 const Selector &Sel, 2418 ASTContext &Context) { 2419 // Check protocols on qualified interfaces. 2420 Decl *GDecl = 0; 2421 for (ObjCObjectPointerType::qual_iterator I = QIdTy->qual_begin(), 2422 E = QIdTy->qual_end(); I != E; ++I) { 2423 if (ObjCPropertyDecl *PD = (*I)->FindPropertyDeclaration(Member)) { 2424 GDecl = PD; 2425 break; 2426 } 2427 // Also must look for a getter name which uses property syntax. 2428 if (ObjCMethodDecl *OMD = (*I)->getInstanceMethod(Sel)) { 2429 GDecl = OMD; 2430 break; 2431 } 2432 } 2433 if (!GDecl) { 2434 for (ObjCObjectPointerType::qual_iterator I = QIdTy->qual_begin(), 2435 E = QIdTy->qual_end(); I != E; ++I) { 2436 // Search in the protocol-qualifier list of current protocol. 2437 GDecl = FindGetterNameDeclFromProtocolList(*I, Member, Sel, Context); 2438 if (GDecl) 2439 return GDecl; 2440 } 2441 } 2442 return GDecl; 2443} 2444 2445Sema::OwningExprResult 2446Sema::ActOnDependentMemberExpr(ExprArg Base, QualType BaseType, 2447 bool IsArrow, SourceLocation OpLoc, 2448 const CXXScopeSpec &SS, 2449 NamedDecl *FirstQualifierInScope, 2450 DeclarationName Name, SourceLocation NameLoc, 2451 const TemplateArgumentListInfo *TemplateArgs) { 2452 Expr *BaseExpr = Base.takeAs<Expr>(); 2453 2454 // Even in dependent contexts, try to diagnose base expressions with 2455 // obviously wrong types, e.g.: 2456 // 2457 // T* t; 2458 // t.f; 2459 // 2460 // In Obj-C++, however, the above expression is valid, since it could be 2461 // accessing the 'f' property if T is an Obj-C interface. The extra check 2462 // allows this, while still reporting an error if T is a struct pointer. 2463 if (!IsArrow) { 2464 const PointerType *PT = BaseType->getAs<PointerType>(); 2465 if (PT && (!getLangOptions().ObjC1 || 2466 PT->getPointeeType()->isRecordType())) { 2467 assert(BaseExpr && "cannot happen with implicit member accesses"); 2468 Diag(NameLoc, diag::err_typecheck_member_reference_struct_union) 2469 << BaseType << BaseExpr->getSourceRange(); 2470 return ExprError(); 2471 } 2472 } 2473 2474 assert(BaseType->isDependentType() || Name.isDependentName() || 2475 isDependentScopeSpecifier(SS)); 2476 2477 // Get the type being accessed in BaseType. If this is an arrow, the BaseExpr 2478 // must have pointer type, and the accessed type is the pointee. 2479 return Owned(CXXDependentScopeMemberExpr::Create(Context, BaseExpr, BaseType, 2480 IsArrow, OpLoc, 2481 static_cast<NestedNameSpecifier*>(SS.getScopeRep()), 2482 SS.getRange(), 2483 FirstQualifierInScope, 2484 Name, NameLoc, 2485 TemplateArgs)); 2486} 2487 2488/// We know that the given qualified member reference points only to 2489/// declarations which do not belong to the static type of the base 2490/// expression. Diagnose the problem. 2491static void DiagnoseQualifiedMemberReference(Sema &SemaRef, 2492 Expr *BaseExpr, 2493 QualType BaseType, 2494 const CXXScopeSpec &SS, 2495 const LookupResult &R) { 2496 // If this is an implicit member access, use a different set of 2497 // diagnostics. 2498 if (!BaseExpr) 2499 return DiagnoseInstanceReference(SemaRef, SS, R); 2500 2501 // FIXME: this is an exceedingly lame diagnostic for some of the more 2502 // complicated cases here. 2503 DeclContext *DC = R.getRepresentativeDecl()->getDeclContext(); 2504 SemaRef.Diag(R.getNameLoc(), diag::err_not_direct_base_or_virtual) 2505 << SS.getRange() << DC << BaseType; 2506} 2507 2508// Check whether the declarations we found through a nested-name 2509// specifier in a member expression are actually members of the base 2510// type. The restriction here is: 2511// 2512// C++ [expr.ref]p2: 2513// ... In these cases, the id-expression shall name a 2514// member of the class or of one of its base classes. 2515// 2516// So it's perfectly legitimate for the nested-name specifier to name 2517// an unrelated class, and for us to find an overload set including 2518// decls from classes which are not superclasses, as long as the decl 2519// we actually pick through overload resolution is from a superclass. 2520bool Sema::CheckQualifiedMemberReference(Expr *BaseExpr, 2521 QualType BaseType, 2522 const CXXScopeSpec &SS, 2523 const LookupResult &R) { 2524 const RecordType *BaseRT = BaseType->getAs<RecordType>(); 2525 if (!BaseRT) { 2526 // We can't check this yet because the base type is still 2527 // dependent. 2528 assert(BaseType->isDependentType()); 2529 return false; 2530 } 2531 CXXRecordDecl *BaseRecord = cast<CXXRecordDecl>(BaseRT->getDecl()); 2532 2533 for (LookupResult::iterator I = R.begin(), E = R.end(); I != E; ++I) { 2534 // If this is an implicit member reference and we find a 2535 // non-instance member, it's not an error. 2536 if (!BaseExpr && !(*I)->isCXXInstanceMember()) 2537 return false; 2538 2539 // Note that we use the DC of the decl, not the underlying decl. 2540 CXXRecordDecl *RecordD = cast<CXXRecordDecl>((*I)->getDeclContext()); 2541 while (RecordD->isAnonymousStructOrUnion()) 2542 RecordD = cast<CXXRecordDecl>(RecordD->getParent()); 2543 2544 llvm::SmallPtrSet<CXXRecordDecl*,4> MemberRecord; 2545 MemberRecord.insert(RecordD->getCanonicalDecl()); 2546 2547 if (!IsProvablyNotDerivedFrom(*this, BaseRecord, MemberRecord)) 2548 return false; 2549 } 2550 2551 DiagnoseQualifiedMemberReference(*this, BaseExpr, BaseType, SS, R); 2552 return true; 2553} 2554 2555static bool 2556LookupMemberExprInRecord(Sema &SemaRef, LookupResult &R, 2557 SourceRange BaseRange, const RecordType *RTy, 2558 SourceLocation OpLoc, CXXScopeSpec &SS) { 2559 RecordDecl *RDecl = RTy->getDecl(); 2560 if (SemaRef.RequireCompleteType(OpLoc, QualType(RTy, 0), 2561 SemaRef.PDiag(diag::err_typecheck_incomplete_tag) 2562 << BaseRange)) 2563 return true; 2564 2565 DeclContext *DC = RDecl; 2566 if (SS.isSet()) { 2567 // If the member name was a qualified-id, look into the 2568 // nested-name-specifier. 2569 DC = SemaRef.computeDeclContext(SS, false); 2570 2571 if (SemaRef.RequireCompleteDeclContext(SS)) { 2572 SemaRef.Diag(SS.getRange().getEnd(), diag::err_typecheck_incomplete_tag) 2573 << SS.getRange() << DC; 2574 return true; 2575 } 2576 2577 assert(DC && "Cannot handle non-computable dependent contexts in lookup"); 2578 2579 if (!isa<TypeDecl>(DC)) { 2580 SemaRef.Diag(R.getNameLoc(), diag::err_qualified_member_nonclass) 2581 << DC << SS.getRange(); 2582 return true; 2583 } 2584 } 2585 2586 // The record definition is complete, now look up the member. 2587 SemaRef.LookupQualifiedName(R, DC); 2588 2589 if (!R.empty()) 2590 return false; 2591 2592 // We didn't find anything with the given name, so try to correct 2593 // for typos. 2594 DeclarationName Name = R.getLookupName(); 2595 if (SemaRef.CorrectTypo(R, 0, &SS, DC, false, Sema::CTC_MemberLookup) && 2596 !R.empty() && 2597 (isa<ValueDecl>(*R.begin()) || isa<FunctionTemplateDecl>(*R.begin()))) { 2598 SemaRef.Diag(R.getNameLoc(), diag::err_no_member_suggest) 2599 << Name << DC << R.getLookupName() << SS.getRange() 2600 << FixItHint::CreateReplacement(R.getNameLoc(), 2601 R.getLookupName().getAsString()); 2602 if (NamedDecl *ND = R.getAsSingle<NamedDecl>()) 2603 SemaRef.Diag(ND->getLocation(), diag::note_previous_decl) 2604 << ND->getDeclName(); 2605 return false; 2606 } else { 2607 R.clear(); 2608 } 2609 2610 return false; 2611} 2612 2613Sema::OwningExprResult 2614Sema::BuildMemberReferenceExpr(ExprArg BaseArg, QualType BaseType, 2615 SourceLocation OpLoc, bool IsArrow, 2616 CXXScopeSpec &SS, 2617 NamedDecl *FirstQualifierInScope, 2618 DeclarationName Name, SourceLocation NameLoc, 2619 const TemplateArgumentListInfo *TemplateArgs) { 2620 Expr *Base = BaseArg.takeAs<Expr>(); 2621 2622 if (BaseType->isDependentType() || 2623 (SS.isSet() && isDependentScopeSpecifier(SS))) 2624 return ActOnDependentMemberExpr(ExprArg(*this, Base), BaseType, 2625 IsArrow, OpLoc, 2626 SS, FirstQualifierInScope, 2627 Name, NameLoc, 2628 TemplateArgs); 2629 2630 LookupResult R(*this, Name, NameLoc, LookupMemberName); 2631 2632 // Implicit member accesses. 2633 if (!Base) { 2634 QualType RecordTy = BaseType; 2635 if (IsArrow) RecordTy = RecordTy->getAs<PointerType>()->getPointeeType(); 2636 if (LookupMemberExprInRecord(*this, R, SourceRange(), 2637 RecordTy->getAs<RecordType>(), 2638 OpLoc, SS)) 2639 return ExprError(); 2640 2641 // Explicit member accesses. 2642 } else { 2643 OwningExprResult Result = 2644 LookupMemberExpr(R, Base, IsArrow, OpLoc, 2645 SS, /*ObjCImpDecl*/ DeclPtrTy()); 2646 2647 if (Result.isInvalid()) { 2648 Owned(Base); 2649 return ExprError(); 2650 } 2651 2652 if (Result.get()) 2653 return move(Result); 2654 } 2655 2656 return BuildMemberReferenceExpr(ExprArg(*this, Base), BaseType, 2657 OpLoc, IsArrow, SS, FirstQualifierInScope, 2658 R, TemplateArgs); 2659} 2660 2661Sema::OwningExprResult 2662Sema::BuildMemberReferenceExpr(ExprArg Base, QualType BaseExprType, 2663 SourceLocation OpLoc, bool IsArrow, 2664 const CXXScopeSpec &SS, 2665 NamedDecl *FirstQualifierInScope, 2666 LookupResult &R, 2667 const TemplateArgumentListInfo *TemplateArgs) { 2668 Expr *BaseExpr = Base.takeAs<Expr>(); 2669 QualType BaseType = BaseExprType; 2670 if (IsArrow) { 2671 assert(BaseType->isPointerType()); 2672 BaseType = BaseType->getAs<PointerType>()->getPointeeType(); 2673 } 2674 R.setBaseObjectType(BaseType); 2675 2676 NestedNameSpecifier *Qualifier = 2677 static_cast<NestedNameSpecifier*>(SS.getScopeRep()); 2678 DeclarationName MemberName = R.getLookupName(); 2679 SourceLocation MemberLoc = R.getNameLoc(); 2680 2681 if (R.isAmbiguous()) 2682 return ExprError(); 2683 2684 if (R.empty()) { 2685 // Rederive where we looked up. 2686 DeclContext *DC = (SS.isSet() 2687 ? computeDeclContext(SS, false) 2688 : BaseType->getAs<RecordType>()->getDecl()); 2689 2690 Diag(R.getNameLoc(), diag::err_no_member) 2691 << MemberName << DC 2692 << (BaseExpr ? BaseExpr->getSourceRange() : SourceRange()); 2693 return ExprError(); 2694 } 2695 2696 // Diagnose lookups that find only declarations from a non-base 2697 // type. This is possible for either qualified lookups (which may 2698 // have been qualified with an unrelated type) or implicit member 2699 // expressions (which were found with unqualified lookup and thus 2700 // may have come from an enclosing scope). Note that it's okay for 2701 // lookup to find declarations from a non-base type as long as those 2702 // aren't the ones picked by overload resolution. 2703 if ((SS.isSet() || !BaseExpr || 2704 (isa<CXXThisExpr>(BaseExpr) && 2705 cast<CXXThisExpr>(BaseExpr)->isImplicit())) && 2706 CheckQualifiedMemberReference(BaseExpr, BaseType, SS, R)) 2707 return ExprError(); 2708 2709 // Construct an unresolved result if we in fact got an unresolved 2710 // result. 2711 if (R.isOverloadedResult() || R.isUnresolvableResult()) { 2712 bool Dependent = 2713 BaseExprType->isDependentType() || 2714 R.isUnresolvableResult() || 2715 OverloadExpr::ComputeDependence(R.begin(), R.end(), TemplateArgs); 2716 2717 // Suppress any lookup-related diagnostics; we'll do these when we 2718 // pick a member. 2719 R.suppressDiagnostics(); 2720 2721 UnresolvedMemberExpr *MemExpr 2722 = UnresolvedMemberExpr::Create(Context, Dependent, 2723 R.isUnresolvableResult(), 2724 BaseExpr, BaseExprType, 2725 IsArrow, OpLoc, 2726 Qualifier, SS.getRange(), 2727 MemberName, MemberLoc, 2728 TemplateArgs); 2729 MemExpr->addDecls(R.begin(), R.end()); 2730 2731 return Owned(MemExpr); 2732 } 2733 2734 assert(R.isSingleResult()); 2735 DeclAccessPair FoundDecl = R.begin().getPair(); 2736 NamedDecl *MemberDecl = R.getFoundDecl(); 2737 2738 // FIXME: diagnose the presence of template arguments now. 2739 2740 // If the decl being referenced had an error, return an error for this 2741 // sub-expr without emitting another error, in order to avoid cascading 2742 // error cases. 2743 if (MemberDecl->isInvalidDecl()) 2744 return ExprError(); 2745 2746 // Handle the implicit-member-access case. 2747 if (!BaseExpr) { 2748 // If this is not an instance member, convert to a non-member access. 2749 if (!MemberDecl->isCXXInstanceMember()) 2750 return BuildDeclarationNameExpr(SS, R.getNameLoc(), MemberDecl); 2751 2752 SourceLocation Loc = R.getNameLoc(); 2753 if (SS.getRange().isValid()) 2754 Loc = SS.getRange().getBegin(); 2755 BaseExpr = new (Context) CXXThisExpr(Loc, BaseExprType,/*isImplicit=*/true); 2756 } 2757 2758 bool ShouldCheckUse = true; 2759 if (CXXMethodDecl *MD = dyn_cast<CXXMethodDecl>(MemberDecl)) { 2760 // Don't diagnose the use of a virtual member function unless it's 2761 // explicitly qualified. 2762 if (MD->isVirtual() && !SS.isSet()) 2763 ShouldCheckUse = false; 2764 } 2765 2766 // Check the use of this member. 2767 if (ShouldCheckUse && DiagnoseUseOfDecl(MemberDecl, MemberLoc)) { 2768 Owned(BaseExpr); 2769 return ExprError(); 2770 } 2771 2772 if (FieldDecl *FD = dyn_cast<FieldDecl>(MemberDecl)) { 2773 // We may have found a field within an anonymous union or struct 2774 // (C++ [class.union]). 2775 if (cast<RecordDecl>(FD->getDeclContext())->isAnonymousStructOrUnion() && 2776 !BaseType->getAs<RecordType>()->getDecl()->isAnonymousStructOrUnion()) 2777 return BuildAnonymousStructUnionMemberReference(MemberLoc, FD, 2778 BaseExpr, OpLoc); 2779 2780 // Figure out the type of the member; see C99 6.5.2.3p3, C++ [expr.ref] 2781 QualType MemberType = FD->getType(); 2782 if (const ReferenceType *Ref = MemberType->getAs<ReferenceType>()) 2783 MemberType = Ref->getPointeeType(); 2784 else { 2785 Qualifiers BaseQuals = BaseType.getQualifiers(); 2786 BaseQuals.removeObjCGCAttr(); 2787 if (FD->isMutable()) BaseQuals.removeConst(); 2788 2789 Qualifiers MemberQuals 2790 = Context.getCanonicalType(MemberType).getQualifiers(); 2791 2792 Qualifiers Combined = BaseQuals + MemberQuals; 2793 if (Combined != MemberQuals) 2794 MemberType = Context.getQualifiedType(MemberType, Combined); 2795 } 2796 2797 MarkDeclarationReferenced(MemberLoc, FD); 2798 if (PerformObjectMemberConversion(BaseExpr, Qualifier, FoundDecl, FD)) 2799 return ExprError(); 2800 return Owned(BuildMemberExpr(Context, BaseExpr, IsArrow, SS, 2801 FD, FoundDecl, MemberLoc, MemberType)); 2802 } 2803 2804 if (VarDecl *Var = dyn_cast<VarDecl>(MemberDecl)) { 2805 MarkDeclarationReferenced(MemberLoc, Var); 2806 return Owned(BuildMemberExpr(Context, BaseExpr, IsArrow, SS, 2807 Var, FoundDecl, MemberLoc, 2808 Var->getType().getNonReferenceType())); 2809 } 2810 2811 if (FunctionDecl *MemberFn = dyn_cast<FunctionDecl>(MemberDecl)) { 2812 MarkDeclarationReferenced(MemberLoc, MemberDecl); 2813 return Owned(BuildMemberExpr(Context, BaseExpr, IsArrow, SS, 2814 MemberFn, FoundDecl, MemberLoc, 2815 MemberFn->getType())); 2816 } 2817 2818 if (EnumConstantDecl *Enum = dyn_cast<EnumConstantDecl>(MemberDecl)) { 2819 MarkDeclarationReferenced(MemberLoc, MemberDecl); 2820 return Owned(BuildMemberExpr(Context, BaseExpr, IsArrow, SS, 2821 Enum, FoundDecl, MemberLoc, Enum->getType())); 2822 } 2823 2824 Owned(BaseExpr); 2825 2826 if (isa<TypeDecl>(MemberDecl)) 2827 return ExprError(Diag(MemberLoc,diag::err_typecheck_member_reference_type) 2828 << MemberName << int(IsArrow)); 2829 2830 // We found a declaration kind that we didn't expect. This is a 2831 // generic error message that tells the user that she can't refer 2832 // to this member with '.' or '->'. 2833 return ExprError(Diag(MemberLoc, 2834 diag::err_typecheck_member_reference_unknown) 2835 << MemberName << int(IsArrow)); 2836} 2837 2838/// Look up the given member of the given non-type-dependent 2839/// expression. This can return in one of two ways: 2840/// * If it returns a sentinel null-but-valid result, the caller will 2841/// assume that lookup was performed and the results written into 2842/// the provided structure. It will take over from there. 2843/// * Otherwise, the returned expression will be produced in place of 2844/// an ordinary member expression. 2845/// 2846/// The ObjCImpDecl bit is a gross hack that will need to be properly 2847/// fixed for ObjC++. 2848Sema::OwningExprResult 2849Sema::LookupMemberExpr(LookupResult &R, Expr *&BaseExpr, 2850 bool &IsArrow, SourceLocation OpLoc, 2851 CXXScopeSpec &SS, 2852 DeclPtrTy ObjCImpDecl) { 2853 assert(BaseExpr && "no base expression"); 2854 2855 // Perform default conversions. 2856 DefaultFunctionArrayConversion(BaseExpr); 2857 2858 QualType BaseType = BaseExpr->getType(); 2859 assert(!BaseType->isDependentType()); 2860 2861 DeclarationName MemberName = R.getLookupName(); 2862 SourceLocation MemberLoc = R.getNameLoc(); 2863 2864 // If the user is trying to apply -> or . to a function pointer 2865 // type, it's probably because they forgot parentheses to call that 2866 // function. Suggest the addition of those parentheses, build the 2867 // call, and continue on. 2868 if (const PointerType *Ptr = BaseType->getAs<PointerType>()) { 2869 if (const FunctionProtoType *Fun 2870 = Ptr->getPointeeType()->getAs<FunctionProtoType>()) { 2871 QualType ResultTy = Fun->getResultType(); 2872 if (Fun->getNumArgs() == 0 && 2873 ((!IsArrow && ResultTy->isRecordType()) || 2874 (IsArrow && ResultTy->isPointerType() && 2875 ResultTy->getAs<PointerType>()->getPointeeType() 2876 ->isRecordType()))) { 2877 SourceLocation Loc = PP.getLocForEndOfToken(BaseExpr->getLocEnd()); 2878 Diag(Loc, diag::err_member_reference_needs_call) 2879 << QualType(Fun, 0) 2880 << FixItHint::CreateInsertion(Loc, "()"); 2881 2882 OwningExprResult NewBase 2883 = ActOnCallExpr(0, ExprArg(*this, BaseExpr), Loc, 2884 MultiExprArg(*this, 0, 0), 0, Loc); 2885 if (NewBase.isInvalid()) 2886 return ExprError(); 2887 2888 BaseExpr = NewBase.takeAs<Expr>(); 2889 DefaultFunctionArrayConversion(BaseExpr); 2890 BaseType = BaseExpr->getType(); 2891 } 2892 } 2893 } 2894 2895 // If this is an Objective-C pseudo-builtin and a definition is provided then 2896 // use that. 2897 if (BaseType->isObjCIdType()) { 2898 if (IsArrow) { 2899 // Handle the following exceptional case PObj->isa. 2900 if (const ObjCObjectPointerType *OPT = 2901 BaseType->getAs<ObjCObjectPointerType>()) { 2902 if (OPT->getPointeeType()->isSpecificBuiltinType(BuiltinType::ObjCId) && 2903 MemberName.getAsIdentifierInfo()->isStr("isa")) 2904 return Owned(new (Context) ObjCIsaExpr(BaseExpr, true, MemberLoc, 2905 Context.getObjCClassType())); 2906 } 2907 } 2908 // We have an 'id' type. Rather than fall through, we check if this 2909 // is a reference to 'isa'. 2910 if (BaseType != Context.ObjCIdRedefinitionType) { 2911 BaseType = Context.ObjCIdRedefinitionType; 2912 ImpCastExprToType(BaseExpr, BaseType, CastExpr::CK_BitCast); 2913 } 2914 } 2915 2916 // If this is an Objective-C pseudo-builtin and a definition is provided then 2917 // use that. 2918 if (Context.isObjCSelType(BaseType)) { 2919 // We have an 'SEL' type. Rather than fall through, we check if this 2920 // is a reference to 'sel_id'. 2921 if (BaseType != Context.ObjCSelRedefinitionType) { 2922 BaseType = Context.ObjCSelRedefinitionType; 2923 ImpCastExprToType(BaseExpr, BaseType, CastExpr::CK_BitCast); 2924 } 2925 } 2926 2927 assert(!BaseType.isNull() && "no type for member expression"); 2928 2929 // Handle properties on ObjC 'Class' types. 2930 if (!IsArrow && BaseType->isObjCClassType()) { 2931 // Also must look for a getter name which uses property syntax. 2932 IdentifierInfo *Member = MemberName.getAsIdentifierInfo(); 2933 Selector Sel = PP.getSelectorTable().getNullarySelector(Member); 2934 if (ObjCMethodDecl *MD = getCurMethodDecl()) { 2935 ObjCInterfaceDecl *IFace = MD->getClassInterface(); 2936 ObjCMethodDecl *Getter; 2937 // FIXME: need to also look locally in the implementation. 2938 if ((Getter = IFace->lookupClassMethod(Sel))) { 2939 // Check the use of this method. 2940 if (DiagnoseUseOfDecl(Getter, MemberLoc)) 2941 return ExprError(); 2942 } 2943 // If we found a getter then this may be a valid dot-reference, we 2944 // will look for the matching setter, in case it is needed. 2945 Selector SetterSel = 2946 SelectorTable::constructSetterName(PP.getIdentifierTable(), 2947 PP.getSelectorTable(), Member); 2948 ObjCMethodDecl *Setter = IFace->lookupClassMethod(SetterSel); 2949 if (!Setter) { 2950 // If this reference is in an @implementation, also check for 'private' 2951 // methods. 2952 Setter = IFace->lookupPrivateInstanceMethod(SetterSel); 2953 } 2954 // Look through local category implementations associated with the class. 2955 if (!Setter) 2956 Setter = IFace->getCategoryClassMethod(SetterSel); 2957 2958 if (Setter && DiagnoseUseOfDecl(Setter, MemberLoc)) 2959 return ExprError(); 2960 2961 if (Getter || Setter) { 2962 QualType PType; 2963 2964 if (Getter) 2965 PType = Getter->getResultType(); 2966 else 2967 // Get the expression type from Setter's incoming parameter. 2968 PType = (*(Setter->param_end() -1))->getType(); 2969 // FIXME: we must check that the setter has property type. 2970 return Owned(new (Context) ObjCImplicitSetterGetterRefExpr(Getter, 2971 PType, 2972 Setter, MemberLoc, BaseExpr)); 2973 } 2974 return ExprError(Diag(MemberLoc, diag::err_property_not_found) 2975 << MemberName << BaseType); 2976 } 2977 } 2978 2979 if (BaseType->isObjCClassType() && 2980 BaseType != Context.ObjCClassRedefinitionType) { 2981 BaseType = Context.ObjCClassRedefinitionType; 2982 ImpCastExprToType(BaseExpr, BaseType, CastExpr::CK_BitCast); 2983 } 2984 2985 if (IsArrow) { 2986 if (const PointerType *PT = BaseType->getAs<PointerType>()) 2987 BaseType = PT->getPointeeType(); 2988 else if (BaseType->isObjCObjectPointerType()) 2989 ; 2990 else if (BaseType->isRecordType()) { 2991 // Recover from arrow accesses to records, e.g.: 2992 // struct MyRecord foo; 2993 // foo->bar 2994 // This is actually well-formed in C++ if MyRecord has an 2995 // overloaded operator->, but that should have been dealt with 2996 // by now. 2997 Diag(OpLoc, diag::err_typecheck_member_reference_suggestion) 2998 << BaseType << int(IsArrow) << BaseExpr->getSourceRange() 2999 << FixItHint::CreateReplacement(OpLoc, "."); 3000 IsArrow = false; 3001 } else { 3002 Diag(MemberLoc, diag::err_typecheck_member_reference_arrow) 3003 << BaseType << BaseExpr->getSourceRange(); 3004 return ExprError(); 3005 } 3006 } else { 3007 // Recover from dot accesses to pointers, e.g.: 3008 // type *foo; 3009 // foo.bar 3010 // This is actually well-formed in two cases: 3011 // - 'type' is an Objective C type 3012 // - 'bar' is a pseudo-destructor name which happens to refer to 3013 // the appropriate pointer type 3014 if (MemberName.getNameKind() != DeclarationName::CXXDestructorName) { 3015 const PointerType *PT = BaseType->getAs<PointerType>(); 3016 if (PT && PT->getPointeeType()->isRecordType()) { 3017 Diag(OpLoc, diag::err_typecheck_member_reference_suggestion) 3018 << BaseType << int(IsArrow) << BaseExpr->getSourceRange() 3019 << FixItHint::CreateReplacement(OpLoc, "->"); 3020 BaseType = PT->getPointeeType(); 3021 IsArrow = true; 3022 } 3023 } 3024 } 3025 3026 // Handle field access to simple records. This also handles access 3027 // to fields of the ObjC 'id' struct. 3028 if (const RecordType *RTy = BaseType->getAs<RecordType>()) { 3029 if (LookupMemberExprInRecord(*this, R, BaseExpr->getSourceRange(), 3030 RTy, OpLoc, SS)) 3031 return ExprError(); 3032 return Owned((Expr*) 0); 3033 } 3034 3035 // Handle access to Objective-C instance variables, such as "Obj->ivar" and 3036 // (*Obj).ivar. 3037 if ((IsArrow && BaseType->isObjCObjectPointerType()) || 3038 (!IsArrow && BaseType->isObjCInterfaceType())) { 3039 const ObjCObjectPointerType *OPT = BaseType->getAs<ObjCObjectPointerType>(); 3040 const ObjCInterfaceType *IFaceT = 3041 OPT ? OPT->getInterfaceType() : BaseType->getAs<ObjCInterfaceType>(); 3042 if (IFaceT) { 3043 IdentifierInfo *Member = MemberName.getAsIdentifierInfo(); 3044 3045 ObjCInterfaceDecl *IDecl = IFaceT->getDecl(); 3046 ObjCInterfaceDecl *ClassDeclared; 3047 ObjCIvarDecl *IV = IDecl->lookupInstanceVariable(Member, ClassDeclared); 3048 3049 if (!IV) { 3050 // Attempt to correct for typos in ivar names. 3051 LookupResult Res(*this, R.getLookupName(), R.getNameLoc(), 3052 LookupMemberName); 3053 if (CorrectTypo(Res, 0, 0, IDecl, false, CTC_MemberLookup) && 3054 (IV = Res.getAsSingle<ObjCIvarDecl>())) { 3055 Diag(R.getNameLoc(), 3056 diag::err_typecheck_member_reference_ivar_suggest) 3057 << IDecl->getDeclName() << MemberName << IV->getDeclName() 3058 << FixItHint::CreateReplacement(R.getNameLoc(), 3059 IV->getNameAsString()); 3060 Diag(IV->getLocation(), diag::note_previous_decl) 3061 << IV->getDeclName(); 3062 } 3063 } 3064 3065 if (IV) { 3066 // If the decl being referenced had an error, return an error for this 3067 // sub-expr without emitting another error, in order to avoid cascading 3068 // error cases. 3069 if (IV->isInvalidDecl()) 3070 return ExprError(); 3071 3072 // Check whether we can reference this field. 3073 if (DiagnoseUseOfDecl(IV, MemberLoc)) 3074 return ExprError(); 3075 if (IV->getAccessControl() != ObjCIvarDecl::Public && 3076 IV->getAccessControl() != ObjCIvarDecl::Package) { 3077 ObjCInterfaceDecl *ClassOfMethodDecl = 0; 3078 if (ObjCMethodDecl *MD = getCurMethodDecl()) 3079 ClassOfMethodDecl = MD->getClassInterface(); 3080 else if (ObjCImpDecl && getCurFunctionDecl()) { 3081 // Case of a c-function declared inside an objc implementation. 3082 // FIXME: For a c-style function nested inside an objc implementation 3083 // class, there is no implementation context available, so we pass 3084 // down the context as argument to this routine. Ideally, this context 3085 // need be passed down in the AST node and somehow calculated from the 3086 // AST for a function decl. 3087 Decl *ImplDecl = ObjCImpDecl.getAs<Decl>(); 3088 if (ObjCImplementationDecl *IMPD = 3089 dyn_cast<ObjCImplementationDecl>(ImplDecl)) 3090 ClassOfMethodDecl = IMPD->getClassInterface(); 3091 else if (ObjCCategoryImplDecl* CatImplClass = 3092 dyn_cast<ObjCCategoryImplDecl>(ImplDecl)) 3093 ClassOfMethodDecl = CatImplClass->getClassInterface(); 3094 } 3095 3096 if (IV->getAccessControl() == ObjCIvarDecl::Private) { 3097 if (ClassDeclared != IDecl || 3098 ClassOfMethodDecl != ClassDeclared) 3099 Diag(MemberLoc, diag::error_private_ivar_access) 3100 << IV->getDeclName(); 3101 } else if (!IDecl->isSuperClassOf(ClassOfMethodDecl)) 3102 // @protected 3103 Diag(MemberLoc, diag::error_protected_ivar_access) 3104 << IV->getDeclName(); 3105 } 3106 3107 return Owned(new (Context) ObjCIvarRefExpr(IV, IV->getType(), 3108 MemberLoc, BaseExpr, 3109 IsArrow)); 3110 } 3111 return ExprError(Diag(MemberLoc, diag::err_typecheck_member_reference_ivar) 3112 << IDecl->getDeclName() << MemberName 3113 << BaseExpr->getSourceRange()); 3114 } 3115 } 3116 // Handle properties on 'id' and qualified "id". 3117 if (!IsArrow && (BaseType->isObjCIdType() || 3118 BaseType->isObjCQualifiedIdType())) { 3119 const ObjCObjectPointerType *QIdTy = BaseType->getAs<ObjCObjectPointerType>(); 3120 IdentifierInfo *Member = MemberName.getAsIdentifierInfo(); 3121 3122 // Check protocols on qualified interfaces. 3123 Selector Sel = PP.getSelectorTable().getNullarySelector(Member); 3124 if (Decl *PMDecl = FindGetterNameDecl(QIdTy, Member, Sel, Context)) { 3125 if (ObjCPropertyDecl *PD = dyn_cast<ObjCPropertyDecl>(PMDecl)) { 3126 // Check the use of this declaration 3127 if (DiagnoseUseOfDecl(PD, MemberLoc)) 3128 return ExprError(); 3129 3130 return Owned(new (Context) ObjCPropertyRefExpr(PD, PD->getType(), 3131 MemberLoc, BaseExpr)); 3132 } 3133 if (ObjCMethodDecl *OMD = dyn_cast<ObjCMethodDecl>(PMDecl)) { 3134 // Check the use of this method. 3135 if (DiagnoseUseOfDecl(OMD, MemberLoc)) 3136 return ExprError(); 3137 3138 return Owned(ObjCMessageExpr::Create(Context, 3139 OMD->getResultType().getNonReferenceType(), 3140 OpLoc, BaseExpr, Sel, 3141 OMD, NULL, 0, MemberLoc)); 3142 } 3143 } 3144 3145 return ExprError(Diag(MemberLoc, diag::err_property_not_found) 3146 << MemberName << BaseType); 3147 } 3148 3149 // Handle Objective-C property access, which is "Obj.property" where Obj is a 3150 // pointer to a (potentially qualified) interface type. 3151 if (!IsArrow) 3152 if (const ObjCObjectPointerType *OPT = 3153 BaseType->getAsObjCInterfacePointerType()) 3154 return HandleExprPropertyRefExpr(OPT, BaseExpr, MemberName, MemberLoc); 3155 3156 // Handle the following exceptional case (*Obj).isa. 3157 if (!IsArrow && 3158 BaseType->isSpecificBuiltinType(BuiltinType::ObjCId) && 3159 MemberName.getAsIdentifierInfo()->isStr("isa")) 3160 return Owned(new (Context) ObjCIsaExpr(BaseExpr, false, MemberLoc, 3161 Context.getObjCClassType())); 3162 3163 // Handle 'field access' to vectors, such as 'V.xx'. 3164 if (BaseType->isExtVectorType()) { 3165 IdentifierInfo *Member = MemberName.getAsIdentifierInfo(); 3166 QualType ret = CheckExtVectorComponent(BaseType, OpLoc, Member, MemberLoc); 3167 if (ret.isNull()) 3168 return ExprError(); 3169 return Owned(new (Context) ExtVectorElementExpr(ret, BaseExpr, *Member, 3170 MemberLoc)); 3171 } 3172 3173 Diag(MemberLoc, diag::err_typecheck_member_reference_struct_union) 3174 << BaseType << BaseExpr->getSourceRange(); 3175 3176 return ExprError(); 3177} 3178 3179/// The main callback when the parser finds something like 3180/// expression . [nested-name-specifier] identifier 3181/// expression -> [nested-name-specifier] identifier 3182/// where 'identifier' encompasses a fairly broad spectrum of 3183/// possibilities, including destructor and operator references. 3184/// 3185/// \param OpKind either tok::arrow or tok::period 3186/// \param HasTrailingLParen whether the next token is '(', which 3187/// is used to diagnose mis-uses of special members that can 3188/// only be called 3189/// \param ObjCImpDecl the current ObjC @implementation decl; 3190/// this is an ugly hack around the fact that ObjC @implementations 3191/// aren't properly put in the context chain 3192Sema::OwningExprResult Sema::ActOnMemberAccessExpr(Scope *S, ExprArg BaseArg, 3193 SourceLocation OpLoc, 3194 tok::TokenKind OpKind, 3195 CXXScopeSpec &SS, 3196 UnqualifiedId &Id, 3197 DeclPtrTy ObjCImpDecl, 3198 bool HasTrailingLParen) { 3199 if (SS.isSet() && SS.isInvalid()) 3200 return ExprError(); 3201 3202 TemplateArgumentListInfo TemplateArgsBuffer; 3203 3204 // Decompose the name into its component parts. 3205 DeclarationName Name; 3206 SourceLocation NameLoc; 3207 const TemplateArgumentListInfo *TemplateArgs; 3208 DecomposeUnqualifiedId(*this, Id, TemplateArgsBuffer, 3209 Name, NameLoc, TemplateArgs); 3210 3211 bool IsArrow = (OpKind == tok::arrow); 3212 3213 NamedDecl *FirstQualifierInScope 3214 = (!SS.isSet() ? 0 : FindFirstQualifierInScope(S, 3215 static_cast<NestedNameSpecifier*>(SS.getScopeRep()))); 3216 3217 // This is a postfix expression, so get rid of ParenListExprs. 3218 BaseArg = MaybeConvertParenListExprToParenExpr(S, move(BaseArg)); 3219 3220 Expr *Base = BaseArg.takeAs<Expr>(); 3221 OwningExprResult Result(*this); 3222 if (Base->getType()->isDependentType() || Name.isDependentName() || 3223 isDependentScopeSpecifier(SS)) { 3224 Result = ActOnDependentMemberExpr(ExprArg(*this, Base), Base->getType(), 3225 IsArrow, OpLoc, 3226 SS, FirstQualifierInScope, 3227 Name, NameLoc, 3228 TemplateArgs); 3229 } else { 3230 LookupResult R(*this, Name, NameLoc, LookupMemberName); 3231 if (TemplateArgs) { 3232 // Re-use the lookup done for the template name. 3233 DecomposeTemplateName(R, Id); 3234 } else { 3235 Result = LookupMemberExpr(R, Base, IsArrow, OpLoc, 3236 SS, ObjCImpDecl); 3237 3238 if (Result.isInvalid()) { 3239 Owned(Base); 3240 return ExprError(); 3241 } 3242 3243 if (Result.get()) { 3244 // The only way a reference to a destructor can be used is to 3245 // immediately call it, which falls into this case. If the 3246 // next token is not a '(', produce a diagnostic and build the 3247 // call now. 3248 if (!HasTrailingLParen && 3249 Id.getKind() == UnqualifiedId::IK_DestructorName) 3250 return DiagnoseDtorReference(NameLoc, move(Result)); 3251 3252 return move(Result); 3253 } 3254 } 3255 3256 Result = BuildMemberReferenceExpr(ExprArg(*this, Base), Base->getType(), 3257 OpLoc, IsArrow, SS, FirstQualifierInScope, 3258 R, TemplateArgs); 3259 } 3260 3261 return move(Result); 3262} 3263 3264Sema::OwningExprResult Sema::BuildCXXDefaultArgExpr(SourceLocation CallLoc, 3265 FunctionDecl *FD, 3266 ParmVarDecl *Param) { 3267 if (Param->hasUnparsedDefaultArg()) { 3268 Diag (CallLoc, 3269 diag::err_use_of_default_argument_to_function_declared_later) << 3270 FD << cast<CXXRecordDecl>(FD->getDeclContext())->getDeclName(); 3271 Diag(UnparsedDefaultArgLocs[Param], 3272 diag::note_default_argument_declared_here); 3273 } else { 3274 if (Param->hasUninstantiatedDefaultArg()) { 3275 Expr *UninstExpr = Param->getUninstantiatedDefaultArg(); 3276 3277 // Instantiate the expression. 3278 MultiLevelTemplateArgumentList ArgList 3279 = getTemplateInstantiationArgs(FD, 0, /*RelativeToPrimary=*/true); 3280 3281 InstantiatingTemplate Inst(*this, CallLoc, Param, 3282 ArgList.getInnermost().getFlatArgumentList(), 3283 ArgList.getInnermost().flat_size()); 3284 3285 OwningExprResult Result = SubstExpr(UninstExpr, ArgList); 3286 if (Result.isInvalid()) 3287 return ExprError(); 3288 3289 // Check the expression as an initializer for the parameter. 3290 InitializedEntity Entity 3291 = InitializedEntity::InitializeParameter(Param); 3292 InitializationKind Kind 3293 = InitializationKind::CreateCopy(Param->getLocation(), 3294 /*FIXME:EqualLoc*/UninstExpr->getSourceRange().getBegin()); 3295 Expr *ResultE = Result.takeAs<Expr>(); 3296 3297 InitializationSequence InitSeq(*this, Entity, Kind, &ResultE, 1); 3298 Result = InitSeq.Perform(*this, Entity, Kind, 3299 MultiExprArg(*this, (void**)&ResultE, 1)); 3300 if (Result.isInvalid()) 3301 return ExprError(); 3302 3303 // Build the default argument expression. 3304 return Owned(CXXDefaultArgExpr::Create(Context, CallLoc, Param, 3305 Result.takeAs<Expr>())); 3306 } 3307 3308 // If the default expression creates temporaries, we need to 3309 // push them to the current stack of expression temporaries so they'll 3310 // be properly destroyed. 3311 // FIXME: We should really be rebuilding the default argument with new 3312 // bound temporaries; see the comment in PR5810. 3313 for (unsigned i = 0, e = Param->getNumDefaultArgTemporaries(); i != e; ++i) 3314 ExprTemporaries.push_back(Param->getDefaultArgTemporary(i)); 3315 } 3316 3317 // We already type-checked the argument, so we know it works. 3318 return Owned(CXXDefaultArgExpr::Create(Context, CallLoc, Param)); 3319} 3320 3321/// ConvertArgumentsForCall - Converts the arguments specified in 3322/// Args/NumArgs to the parameter types of the function FDecl with 3323/// function prototype Proto. Call is the call expression itself, and 3324/// Fn is the function expression. For a C++ member function, this 3325/// routine does not attempt to convert the object argument. Returns 3326/// true if the call is ill-formed. 3327bool 3328Sema::ConvertArgumentsForCall(CallExpr *Call, Expr *Fn, 3329 FunctionDecl *FDecl, 3330 const FunctionProtoType *Proto, 3331 Expr **Args, unsigned NumArgs, 3332 SourceLocation RParenLoc) { 3333 // C99 6.5.2.2p7 - the arguments are implicitly converted, as if by 3334 // assignment, to the types of the corresponding parameter, ... 3335 unsigned NumArgsInProto = Proto->getNumArgs(); 3336 bool Invalid = false; 3337 3338 // If too few arguments are available (and we don't have default 3339 // arguments for the remaining parameters), don't make the call. 3340 if (NumArgs < NumArgsInProto) { 3341 if (!FDecl || NumArgs < FDecl->getMinRequiredArguments()) 3342 return Diag(RParenLoc, diag::err_typecheck_call_too_few_args) 3343 << Fn->getType()->isBlockPointerType() 3344 << NumArgsInProto << NumArgs << Fn->getSourceRange(); 3345 Call->setNumArgs(Context, NumArgsInProto); 3346 } 3347 3348 // If too many are passed and not variadic, error on the extras and drop 3349 // them. 3350 if (NumArgs > NumArgsInProto) { 3351 if (!Proto->isVariadic()) { 3352 Diag(Args[NumArgsInProto]->getLocStart(), 3353 diag::err_typecheck_call_too_many_args) 3354 << Fn->getType()->isBlockPointerType() 3355 << NumArgsInProto << NumArgs << Fn->getSourceRange() 3356 << SourceRange(Args[NumArgsInProto]->getLocStart(), 3357 Args[NumArgs-1]->getLocEnd()); 3358 // This deletes the extra arguments. 3359 Call->setNumArgs(Context, NumArgsInProto); 3360 return true; 3361 } 3362 } 3363 llvm::SmallVector<Expr *, 8> AllArgs; 3364 VariadicCallType CallType = 3365 Proto->isVariadic() ? VariadicFunction : VariadicDoesNotApply; 3366 if (Fn->getType()->isBlockPointerType()) 3367 CallType = VariadicBlock; // Block 3368 else if (isa<MemberExpr>(Fn)) 3369 CallType = VariadicMethod; 3370 Invalid = GatherArgumentsForCall(Call->getSourceRange().getBegin(), FDecl, 3371 Proto, 0, Args, NumArgs, AllArgs, CallType); 3372 if (Invalid) 3373 return true; 3374 unsigned TotalNumArgs = AllArgs.size(); 3375 for (unsigned i = 0; i < TotalNumArgs; ++i) 3376 Call->setArg(i, AllArgs[i]); 3377 3378 return false; 3379} 3380 3381bool Sema::GatherArgumentsForCall(SourceLocation CallLoc, 3382 FunctionDecl *FDecl, 3383 const FunctionProtoType *Proto, 3384 unsigned FirstProtoArg, 3385 Expr **Args, unsigned NumArgs, 3386 llvm::SmallVector<Expr *, 8> &AllArgs, 3387 VariadicCallType CallType) { 3388 unsigned NumArgsInProto = Proto->getNumArgs(); 3389 unsigned NumArgsToCheck = NumArgs; 3390 bool Invalid = false; 3391 if (NumArgs != NumArgsInProto) 3392 // Use default arguments for missing arguments 3393 NumArgsToCheck = NumArgsInProto; 3394 unsigned ArgIx = 0; 3395 // Continue to check argument types (even if we have too few/many args). 3396 for (unsigned i = FirstProtoArg; i != NumArgsToCheck; i++) { 3397 QualType ProtoArgType = Proto->getArgType(i); 3398 3399 Expr *Arg; 3400 if (ArgIx < NumArgs) { 3401 Arg = Args[ArgIx++]; 3402 3403 if (RequireCompleteType(Arg->getSourceRange().getBegin(), 3404 ProtoArgType, 3405 PDiag(diag::err_call_incomplete_argument) 3406 << Arg->getSourceRange())) 3407 return true; 3408 3409 // Pass the argument 3410 ParmVarDecl *Param = 0; 3411 if (FDecl && i < FDecl->getNumParams()) 3412 Param = FDecl->getParamDecl(i); 3413 3414 3415 InitializedEntity Entity = 3416 Param? InitializedEntity::InitializeParameter(Param) 3417 : InitializedEntity::InitializeParameter(ProtoArgType); 3418 OwningExprResult ArgE = PerformCopyInitialization(Entity, 3419 SourceLocation(), 3420 Owned(Arg)); 3421 if (ArgE.isInvalid()) 3422 return true; 3423 3424 Arg = ArgE.takeAs<Expr>(); 3425 } else { 3426 ParmVarDecl *Param = FDecl->getParamDecl(i); 3427 3428 OwningExprResult ArgExpr = 3429 BuildCXXDefaultArgExpr(CallLoc, FDecl, Param); 3430 if (ArgExpr.isInvalid()) 3431 return true; 3432 3433 Arg = ArgExpr.takeAs<Expr>(); 3434 } 3435 AllArgs.push_back(Arg); 3436 } 3437 3438 // If this is a variadic call, handle args passed through "...". 3439 if (CallType != VariadicDoesNotApply) { 3440 // Promote the arguments (C99 6.5.2.2p7). 3441 for (unsigned i = ArgIx; i < NumArgs; i++) { 3442 Expr *Arg = Args[i]; 3443 Invalid |= DefaultVariadicArgumentPromotion(Arg, CallType); 3444 AllArgs.push_back(Arg); 3445 } 3446 } 3447 return Invalid; 3448} 3449 3450/// ActOnCallExpr - Handle a call to Fn with the specified array of arguments. 3451/// This provides the location of the left/right parens and a list of comma 3452/// locations. 3453Action::OwningExprResult 3454Sema::ActOnCallExpr(Scope *S, ExprArg fn, SourceLocation LParenLoc, 3455 MultiExprArg args, 3456 SourceLocation *CommaLocs, SourceLocation RParenLoc) { 3457 unsigned NumArgs = args.size(); 3458 3459 // Since this might be a postfix expression, get rid of ParenListExprs. 3460 fn = MaybeConvertParenListExprToParenExpr(S, move(fn)); 3461 3462 Expr *Fn = fn.takeAs<Expr>(); 3463 Expr **Args = reinterpret_cast<Expr**>(args.release()); 3464 assert(Fn && "no function call expression"); 3465 3466 if (getLangOptions().CPlusPlus) { 3467 // If this is a pseudo-destructor expression, build the call immediately. 3468 if (isa<CXXPseudoDestructorExpr>(Fn)) { 3469 if (NumArgs > 0) { 3470 // Pseudo-destructor calls should not have any arguments. 3471 Diag(Fn->getLocStart(), diag::err_pseudo_dtor_call_with_args) 3472 << FixItHint::CreateRemoval( 3473 SourceRange(Args[0]->getLocStart(), 3474 Args[NumArgs-1]->getLocEnd())); 3475 3476 for (unsigned I = 0; I != NumArgs; ++I) 3477 Args[I]->Destroy(Context); 3478 3479 NumArgs = 0; 3480 } 3481 3482 return Owned(new (Context) CallExpr(Context, Fn, 0, 0, Context.VoidTy, 3483 RParenLoc)); 3484 } 3485 3486 // Determine whether this is a dependent call inside a C++ template, 3487 // in which case we won't do any semantic analysis now. 3488 // FIXME: Will need to cache the results of name lookup (including ADL) in 3489 // Fn. 3490 bool Dependent = false; 3491 if (Fn->isTypeDependent()) 3492 Dependent = true; 3493 else if (Expr::hasAnyTypeDependentArguments(Args, NumArgs)) 3494 Dependent = true; 3495 3496 if (Dependent) 3497 return Owned(new (Context) CallExpr(Context, Fn, Args, NumArgs, 3498 Context.DependentTy, RParenLoc)); 3499 3500 // Determine whether this is a call to an object (C++ [over.call.object]). 3501 if (Fn->getType()->isRecordType()) 3502 return Owned(BuildCallToObjectOfClassType(S, Fn, LParenLoc, Args, NumArgs, 3503 CommaLocs, RParenLoc)); 3504 3505 Expr *NakedFn = Fn->IgnoreParens(); 3506 3507 // Determine whether this is a call to an unresolved member function. 3508 if (UnresolvedMemberExpr *MemE = dyn_cast<UnresolvedMemberExpr>(NakedFn)) { 3509 // If lookup was unresolved but not dependent (i.e. didn't find 3510 // an unresolved using declaration), it has to be an overloaded 3511 // function set, which means it must contain either multiple 3512 // declarations (all methods or method templates) or a single 3513 // method template. 3514 assert((MemE->getNumDecls() > 1) || 3515 isa<FunctionTemplateDecl>(*MemE->decls_begin())); 3516 (void)MemE; 3517 3518 return BuildCallToMemberFunction(S, Fn, LParenLoc, Args, NumArgs, 3519 CommaLocs, RParenLoc); 3520 } 3521 3522 // Determine whether this is a call to a member function. 3523 if (MemberExpr *MemExpr = dyn_cast<MemberExpr>(NakedFn)) { 3524 NamedDecl *MemDecl = MemExpr->getMemberDecl(); 3525 if (isa<CXXMethodDecl>(MemDecl)) 3526 return BuildCallToMemberFunction(S, Fn, LParenLoc, Args, NumArgs, 3527 CommaLocs, RParenLoc); 3528 } 3529 3530 // Determine whether this is a call to a pointer-to-member function. 3531 if (BinaryOperator *BO = dyn_cast<BinaryOperator>(NakedFn)) { 3532 if (BO->getOpcode() == BinaryOperator::PtrMemD || 3533 BO->getOpcode() == BinaryOperator::PtrMemI) { 3534 if (const FunctionProtoType *FPT = 3535 dyn_cast<FunctionProtoType>(BO->getType())) { 3536 QualType ResultTy = FPT->getResultType().getNonReferenceType(); 3537 3538 ExprOwningPtr<CXXMemberCallExpr> 3539 TheCall(this, new (Context) CXXMemberCallExpr(Context, BO, Args, 3540 NumArgs, ResultTy, 3541 RParenLoc)); 3542 3543 if (CheckCallReturnType(FPT->getResultType(), 3544 BO->getRHS()->getSourceRange().getBegin(), 3545 TheCall.get(), 0)) 3546 return ExprError(); 3547 3548 if (ConvertArgumentsForCall(&*TheCall, BO, 0, FPT, Args, NumArgs, 3549 RParenLoc)) 3550 return ExprError(); 3551 3552 return Owned(MaybeBindToTemporary(TheCall.release()).release()); 3553 } 3554 return ExprError(Diag(Fn->getLocStart(), 3555 diag::err_typecheck_call_not_function) 3556 << Fn->getType() << Fn->getSourceRange()); 3557 } 3558 } 3559 } 3560 3561 // If we're directly calling a function, get the appropriate declaration. 3562 // Also, in C++, keep track of whether we should perform argument-dependent 3563 // lookup and whether there were any explicitly-specified template arguments. 3564 3565 Expr *NakedFn = Fn->IgnoreParens(); 3566 if (isa<UnresolvedLookupExpr>(NakedFn)) { 3567 UnresolvedLookupExpr *ULE = cast<UnresolvedLookupExpr>(NakedFn); 3568 return BuildOverloadedCallExpr(S, Fn, ULE, LParenLoc, Args, NumArgs, 3569 CommaLocs, RParenLoc); 3570 } 3571 3572 NamedDecl *NDecl = 0; 3573 if (isa<DeclRefExpr>(NakedFn)) 3574 NDecl = cast<DeclRefExpr>(NakedFn)->getDecl(); 3575 3576 return BuildResolvedCallExpr(Fn, NDecl, LParenLoc, Args, NumArgs, RParenLoc); 3577} 3578 3579/// BuildResolvedCallExpr - Build a call to a resolved expression, 3580/// i.e. an expression not of \p OverloadTy. The expression should 3581/// unary-convert to an expression of function-pointer or 3582/// block-pointer type. 3583/// 3584/// \param NDecl the declaration being called, if available 3585Sema::OwningExprResult 3586Sema::BuildResolvedCallExpr(Expr *Fn, NamedDecl *NDecl, 3587 SourceLocation LParenLoc, 3588 Expr **Args, unsigned NumArgs, 3589 SourceLocation RParenLoc) { 3590 FunctionDecl *FDecl = dyn_cast_or_null<FunctionDecl>(NDecl); 3591 3592 // Promote the function operand. 3593 UsualUnaryConversions(Fn); 3594 3595 // Make the call expr early, before semantic checks. This guarantees cleanup 3596 // of arguments and function on error. 3597 ExprOwningPtr<CallExpr> TheCall(this, new (Context) CallExpr(Context, Fn, 3598 Args, NumArgs, 3599 Context.BoolTy, 3600 RParenLoc)); 3601 3602 const FunctionType *FuncT; 3603 if (!Fn->getType()->isBlockPointerType()) { 3604 // C99 6.5.2.2p1 - "The expression that denotes the called function shall 3605 // have type pointer to function". 3606 const PointerType *PT = Fn->getType()->getAs<PointerType>(); 3607 if (PT == 0) 3608 return ExprError(Diag(LParenLoc, diag::err_typecheck_call_not_function) 3609 << Fn->getType() << Fn->getSourceRange()); 3610 FuncT = PT->getPointeeType()->getAs<FunctionType>(); 3611 } else { // This is a block call. 3612 FuncT = Fn->getType()->getAs<BlockPointerType>()->getPointeeType()-> 3613 getAs<FunctionType>(); 3614 } 3615 if (FuncT == 0) 3616 return ExprError(Diag(LParenLoc, diag::err_typecheck_call_not_function) 3617 << Fn->getType() << Fn->getSourceRange()); 3618 3619 // Check for a valid return type 3620 if (CheckCallReturnType(FuncT->getResultType(), 3621 Fn->getSourceRange().getBegin(), TheCall.get(), 3622 FDecl)) 3623 return ExprError(); 3624 3625 // We know the result type of the call, set it. 3626 TheCall->setType(FuncT->getResultType().getNonReferenceType()); 3627 3628 if (const FunctionProtoType *Proto = dyn_cast<FunctionProtoType>(FuncT)) { 3629 if (ConvertArgumentsForCall(&*TheCall, Fn, FDecl, Proto, Args, NumArgs, 3630 RParenLoc)) 3631 return ExprError(); 3632 } else { 3633 assert(isa<FunctionNoProtoType>(FuncT) && "Unknown FunctionType!"); 3634 3635 if (FDecl) { 3636 // Check if we have too few/too many template arguments, based 3637 // on our knowledge of the function definition. 3638 const FunctionDecl *Def = 0; 3639 if (FDecl->getBody(Def) && NumArgs != Def->param_size()) { 3640 const FunctionProtoType *Proto = 3641 Def->getType()->getAs<FunctionProtoType>(); 3642 if (!Proto || !(Proto->isVariadic() && NumArgs >= Def->param_size())) { 3643 Diag(RParenLoc, diag::warn_call_wrong_number_of_arguments) 3644 << (NumArgs > Def->param_size()) << FDecl << Fn->getSourceRange(); 3645 } 3646 } 3647 } 3648 3649 // Promote the arguments (C99 6.5.2.2p6). 3650 for (unsigned i = 0; i != NumArgs; i++) { 3651 Expr *Arg = Args[i]; 3652 DefaultArgumentPromotion(Arg); 3653 if (RequireCompleteType(Arg->getSourceRange().getBegin(), 3654 Arg->getType(), 3655 PDiag(diag::err_call_incomplete_argument) 3656 << Arg->getSourceRange())) 3657 return ExprError(); 3658 TheCall->setArg(i, Arg); 3659 } 3660 } 3661 3662 if (CXXMethodDecl *Method = dyn_cast_or_null<CXXMethodDecl>(FDecl)) 3663 if (!Method->isStatic()) 3664 return ExprError(Diag(LParenLoc, diag::err_member_call_without_object) 3665 << Fn->getSourceRange()); 3666 3667 // Check for sentinels 3668 if (NDecl) 3669 DiagnoseSentinelCalls(NDecl, LParenLoc, Args, NumArgs); 3670 3671 // Do special checking on direct calls to functions. 3672 if (FDecl) { 3673 if (CheckFunctionCall(FDecl, TheCall.get())) 3674 return ExprError(); 3675 3676 if (unsigned BuiltinID = FDecl->getBuiltinID()) 3677 return CheckBuiltinFunctionCall(BuiltinID, TheCall.take()); 3678 } else if (NDecl) { 3679 if (CheckBlockCall(NDecl, TheCall.get())) 3680 return ExprError(); 3681 } 3682 3683 return MaybeBindToTemporary(TheCall.take()); 3684} 3685 3686Action::OwningExprResult 3687Sema::ActOnCompoundLiteral(SourceLocation LParenLoc, TypeTy *Ty, 3688 SourceLocation RParenLoc, ExprArg InitExpr) { 3689 assert((Ty != 0) && "ActOnCompoundLiteral(): missing type"); 3690 // FIXME: put back this assert when initializers are worked out. 3691 //assert((InitExpr != 0) && "ActOnCompoundLiteral(): missing expression"); 3692 3693 TypeSourceInfo *TInfo; 3694 QualType literalType = GetTypeFromParser(Ty, &TInfo); 3695 if (!TInfo) 3696 TInfo = Context.getTrivialTypeSourceInfo(literalType); 3697 3698 return BuildCompoundLiteralExpr(LParenLoc, TInfo, RParenLoc, move(InitExpr)); 3699} 3700 3701Action::OwningExprResult 3702Sema::BuildCompoundLiteralExpr(SourceLocation LParenLoc, TypeSourceInfo *TInfo, 3703 SourceLocation RParenLoc, ExprArg InitExpr) { 3704 QualType literalType = TInfo->getType(); 3705 Expr *literalExpr = static_cast<Expr*>(InitExpr.get()); 3706 3707 if (literalType->isArrayType()) { 3708 if (literalType->isVariableArrayType()) 3709 return ExprError(Diag(LParenLoc, diag::err_variable_object_no_init) 3710 << SourceRange(LParenLoc, literalExpr->getSourceRange().getEnd())); 3711 } else if (!literalType->isDependentType() && 3712 RequireCompleteType(LParenLoc, literalType, 3713 PDiag(diag::err_typecheck_decl_incomplete_type) 3714 << SourceRange(LParenLoc, 3715 literalExpr->getSourceRange().getEnd()))) 3716 return ExprError(); 3717 3718 InitializedEntity Entity 3719 = InitializedEntity::InitializeTemporary(literalType); 3720 InitializationKind Kind 3721 = InitializationKind::CreateCast(SourceRange(LParenLoc, RParenLoc), 3722 /*IsCStyleCast=*/true); 3723 InitializationSequence InitSeq(*this, Entity, Kind, &literalExpr, 1); 3724 OwningExprResult Result = InitSeq.Perform(*this, Entity, Kind, 3725 MultiExprArg(*this, (void**)&literalExpr, 1), 3726 &literalType); 3727 if (Result.isInvalid()) 3728 return ExprError(); 3729 InitExpr.release(); 3730 literalExpr = static_cast<Expr*>(Result.get()); 3731 3732 bool isFileScope = getCurFunctionOrMethodDecl() == 0; 3733 if (isFileScope) { // 6.5.2.5p3 3734 if (CheckForConstantInitializer(literalExpr, literalType)) 3735 return ExprError(); 3736 } 3737 3738 Result.release(); 3739 3740 return Owned(new (Context) CompoundLiteralExpr(LParenLoc, TInfo, literalType, 3741 literalExpr, isFileScope)); 3742} 3743 3744Action::OwningExprResult 3745Sema::ActOnInitList(SourceLocation LBraceLoc, MultiExprArg initlist, 3746 SourceLocation RBraceLoc) { 3747 unsigned NumInit = initlist.size(); 3748 Expr **InitList = reinterpret_cast<Expr**>(initlist.release()); 3749 3750 // Semantic analysis for initializers is done by ActOnDeclarator() and 3751 // CheckInitializer() - it requires knowledge of the object being intialized. 3752 3753 InitListExpr *E = new (Context) InitListExpr(Context, LBraceLoc, InitList, 3754 NumInit, RBraceLoc); 3755 E->setType(Context.VoidTy); // FIXME: just a place holder for now. 3756 return Owned(E); 3757} 3758 3759static CastExpr::CastKind getScalarCastKind(ASTContext &Context, 3760 QualType SrcTy, QualType DestTy) { 3761 if (Context.hasSameUnqualifiedType(SrcTy, DestTy)) 3762 return CastExpr::CK_NoOp; 3763 3764 if (SrcTy->hasPointerRepresentation()) { 3765 if (DestTy->hasPointerRepresentation()) 3766 return DestTy->isObjCObjectPointerType() ? 3767 CastExpr::CK_AnyPointerToObjCPointerCast : 3768 CastExpr::CK_BitCast; 3769 if (DestTy->isIntegerType()) 3770 return CastExpr::CK_PointerToIntegral; 3771 } 3772 3773 if (SrcTy->isIntegerType()) { 3774 if (DestTy->isIntegerType()) 3775 return CastExpr::CK_IntegralCast; 3776 if (DestTy->hasPointerRepresentation()) 3777 return CastExpr::CK_IntegralToPointer; 3778 if (DestTy->isRealFloatingType()) 3779 return CastExpr::CK_IntegralToFloating; 3780 } 3781 3782 if (SrcTy->isRealFloatingType()) { 3783 if (DestTy->isRealFloatingType()) 3784 return CastExpr::CK_FloatingCast; 3785 if (DestTy->isIntegerType()) 3786 return CastExpr::CK_FloatingToIntegral; 3787 } 3788 3789 // FIXME: Assert here. 3790 // assert(false && "Unhandled cast combination!"); 3791 return CastExpr::CK_Unknown; 3792} 3793 3794/// CheckCastTypes - Check type constraints for casting between types. 3795bool Sema::CheckCastTypes(SourceRange TyR, QualType castType, Expr *&castExpr, 3796 CastExpr::CastKind& Kind, 3797 bool FunctionalStyle) { 3798 if (getLangOptions().CPlusPlus) 3799 return CXXCheckCStyleCast(TyR, castType, castExpr, Kind, FunctionalStyle); 3800 3801 DefaultFunctionArrayLvalueConversion(castExpr); 3802 3803 // C99 6.5.4p2: the cast type needs to be void or scalar and the expression 3804 // type needs to be scalar. 3805 if (castType->isVoidType()) { 3806 // Cast to void allows any expr type. 3807 Kind = CastExpr::CK_ToVoid; 3808 return false; 3809 } 3810 3811 if (!castType->isScalarType() && !castType->isVectorType()) { 3812 if (Context.hasSameUnqualifiedType(castType, castExpr->getType()) && 3813 (castType->isStructureType() || castType->isUnionType())) { 3814 // GCC struct/union extension: allow cast to self. 3815 // FIXME: Check that the cast destination type is complete. 3816 Diag(TyR.getBegin(), diag::ext_typecheck_cast_nonscalar) 3817 << castType << castExpr->getSourceRange(); 3818 Kind = CastExpr::CK_NoOp; 3819 return false; 3820 } 3821 3822 if (castType->isUnionType()) { 3823 // GCC cast to union extension 3824 RecordDecl *RD = castType->getAs<RecordType>()->getDecl(); 3825 RecordDecl::field_iterator Field, FieldEnd; 3826 for (Field = RD->field_begin(), FieldEnd = RD->field_end(); 3827 Field != FieldEnd; ++Field) { 3828 if (Context.hasSameUnqualifiedType(Field->getType(), 3829 castExpr->getType())) { 3830 Diag(TyR.getBegin(), diag::ext_typecheck_cast_to_union) 3831 << castExpr->getSourceRange(); 3832 break; 3833 } 3834 } 3835 if (Field == FieldEnd) 3836 return Diag(TyR.getBegin(), diag::err_typecheck_cast_to_union_no_type) 3837 << castExpr->getType() << castExpr->getSourceRange(); 3838 Kind = CastExpr::CK_ToUnion; 3839 return false; 3840 } 3841 3842 // Reject any other conversions to non-scalar types. 3843 return Diag(TyR.getBegin(), diag::err_typecheck_cond_expect_scalar) 3844 << castType << castExpr->getSourceRange(); 3845 } 3846 3847 if (!castExpr->getType()->isScalarType() && 3848 !castExpr->getType()->isVectorType()) { 3849 return Diag(castExpr->getLocStart(), 3850 diag::err_typecheck_expect_scalar_operand) 3851 << castExpr->getType() << castExpr->getSourceRange(); 3852 } 3853 3854 if (castType->isExtVectorType()) 3855 return CheckExtVectorCast(TyR, castType, castExpr, Kind); 3856 3857 if (castType->isVectorType()) 3858 return CheckVectorCast(TyR, castType, castExpr->getType(), Kind); 3859 if (castExpr->getType()->isVectorType()) 3860 return CheckVectorCast(TyR, castExpr->getType(), castType, Kind); 3861 3862 if (isa<ObjCSelectorExpr>(castExpr)) 3863 return Diag(castExpr->getLocStart(), diag::err_cast_selector_expr); 3864 3865 if (!castType->isArithmeticType()) { 3866 QualType castExprType = castExpr->getType(); 3867 if (!castExprType->isIntegralType() && castExprType->isArithmeticType()) 3868 return Diag(castExpr->getLocStart(), 3869 diag::err_cast_pointer_from_non_pointer_int) 3870 << castExprType << castExpr->getSourceRange(); 3871 } else if (!castExpr->getType()->isArithmeticType()) { 3872 if (!castType->isIntegralType() && castType->isArithmeticType()) 3873 return Diag(castExpr->getLocStart(), 3874 diag::err_cast_pointer_to_non_pointer_int) 3875 << castType << castExpr->getSourceRange(); 3876 } 3877 3878 Kind = getScalarCastKind(Context, castExpr->getType(), castType); 3879 return false; 3880} 3881 3882bool Sema::CheckVectorCast(SourceRange R, QualType VectorTy, QualType Ty, 3883 CastExpr::CastKind &Kind) { 3884 assert(VectorTy->isVectorType() && "Not a vector type!"); 3885 3886 if (Ty->isVectorType() || Ty->isIntegerType()) { 3887 if (Context.getTypeSize(VectorTy) != Context.getTypeSize(Ty)) 3888 return Diag(R.getBegin(), 3889 Ty->isVectorType() ? 3890 diag::err_invalid_conversion_between_vectors : 3891 diag::err_invalid_conversion_between_vector_and_integer) 3892 << VectorTy << Ty << R; 3893 } else 3894 return Diag(R.getBegin(), 3895 diag::err_invalid_conversion_between_vector_and_scalar) 3896 << VectorTy << Ty << R; 3897 3898 Kind = CastExpr::CK_BitCast; 3899 return false; 3900} 3901 3902bool Sema::CheckExtVectorCast(SourceRange R, QualType DestTy, Expr *&CastExpr, 3903 CastExpr::CastKind &Kind) { 3904 assert(DestTy->isExtVectorType() && "Not an extended vector type!"); 3905 3906 QualType SrcTy = CastExpr->getType(); 3907 3908 // If SrcTy is a VectorType, the total size must match to explicitly cast to 3909 // an ExtVectorType. 3910 if (SrcTy->isVectorType()) { 3911 if (Context.getTypeSize(DestTy) != Context.getTypeSize(SrcTy)) 3912 return Diag(R.getBegin(),diag::err_invalid_conversion_between_ext_vectors) 3913 << DestTy << SrcTy << R; 3914 Kind = CastExpr::CK_BitCast; 3915 return false; 3916 } 3917 3918 // All non-pointer scalars can be cast to ExtVector type. The appropriate 3919 // conversion will take place first from scalar to elt type, and then 3920 // splat from elt type to vector. 3921 if (SrcTy->isPointerType()) 3922 return Diag(R.getBegin(), 3923 diag::err_invalid_conversion_between_vector_and_scalar) 3924 << DestTy << SrcTy << R; 3925 3926 QualType DestElemTy = DestTy->getAs<ExtVectorType>()->getElementType(); 3927 ImpCastExprToType(CastExpr, DestElemTy, 3928 getScalarCastKind(Context, SrcTy, DestElemTy)); 3929 3930 Kind = CastExpr::CK_VectorSplat; 3931 return false; 3932} 3933 3934Action::OwningExprResult 3935Sema::ActOnCastExpr(Scope *S, SourceLocation LParenLoc, TypeTy *Ty, 3936 SourceLocation RParenLoc, ExprArg Op) { 3937 assert((Ty != 0) && (Op.get() != 0) && 3938 "ActOnCastExpr(): missing type or expr"); 3939 3940 TypeSourceInfo *castTInfo; 3941 QualType castType = GetTypeFromParser(Ty, &castTInfo); 3942 if (!castTInfo) 3943 castTInfo = Context.getTrivialTypeSourceInfo(castType); 3944 3945 // If the Expr being casted is a ParenListExpr, handle it specially. 3946 Expr *castExpr = (Expr *)Op.get(); 3947 if (isa<ParenListExpr>(castExpr)) 3948 return ActOnCastOfParenListExpr(S, LParenLoc, RParenLoc, move(Op), 3949 castTInfo); 3950 3951 return BuildCStyleCastExpr(LParenLoc, castTInfo, RParenLoc, move(Op)); 3952} 3953 3954Action::OwningExprResult 3955Sema::BuildCStyleCastExpr(SourceLocation LParenLoc, TypeSourceInfo *Ty, 3956 SourceLocation RParenLoc, ExprArg Op) { 3957 Expr *castExpr = static_cast<Expr*>(Op.get()); 3958 3959 CastExpr::CastKind Kind = CastExpr::CK_Unknown; 3960 // FIXME: Initialize base path! 3961 CXXBaseSpecifierArray BasePath; 3962 if (CheckCastTypes(SourceRange(LParenLoc, RParenLoc), Ty->getType(), castExpr, 3963 Kind)) 3964 return ExprError(); 3965 3966 Op.release(); 3967 return Owned(new (Context) CStyleCastExpr(Ty->getType().getNonReferenceType(), 3968 Kind, castExpr, BasePath, Ty, 3969 LParenLoc, RParenLoc)); 3970} 3971 3972/// This is not an AltiVec-style cast, so turn the ParenListExpr into a sequence 3973/// of comma binary operators. 3974Action::OwningExprResult 3975Sema::MaybeConvertParenListExprToParenExpr(Scope *S, ExprArg EA) { 3976 Expr *expr = EA.takeAs<Expr>(); 3977 ParenListExpr *E = dyn_cast<ParenListExpr>(expr); 3978 if (!E) 3979 return Owned(expr); 3980 3981 OwningExprResult Result(*this, E->getExpr(0)); 3982 3983 for (unsigned i = 1, e = E->getNumExprs(); i != e && !Result.isInvalid(); ++i) 3984 Result = ActOnBinOp(S, E->getExprLoc(), tok::comma, move(Result), 3985 Owned(E->getExpr(i))); 3986 3987 return ActOnParenExpr(E->getLParenLoc(), E->getRParenLoc(), move(Result)); 3988} 3989 3990Action::OwningExprResult 3991Sema::ActOnCastOfParenListExpr(Scope *S, SourceLocation LParenLoc, 3992 SourceLocation RParenLoc, ExprArg Op, 3993 TypeSourceInfo *TInfo) { 3994 ParenListExpr *PE = (ParenListExpr *)Op.get(); 3995 QualType Ty = TInfo->getType(); 3996 3997 // If this is an altivec initializer, '(' type ')' '(' init, ..., init ')' 3998 // then handle it as such. 3999 if (getLangOptions().AltiVec && Ty->isVectorType()) { 4000 if (PE->getNumExprs() == 0) { 4001 Diag(PE->getExprLoc(), diag::err_altivec_empty_initializer); 4002 return ExprError(); 4003 } 4004 4005 llvm::SmallVector<Expr *, 8> initExprs; 4006 for (unsigned i = 0, e = PE->getNumExprs(); i != e; ++i) 4007 initExprs.push_back(PE->getExpr(i)); 4008 4009 // FIXME: This means that pretty-printing the final AST will produce curly 4010 // braces instead of the original commas. 4011 Op.release(); 4012 InitListExpr *E = new (Context) InitListExpr(Context, LParenLoc, 4013 &initExprs[0], 4014 initExprs.size(), RParenLoc); 4015 E->setType(Ty); 4016 return BuildCompoundLiteralExpr(LParenLoc, TInfo, RParenLoc, Owned(E)); 4017 } else { 4018 // This is not an AltiVec-style cast, so turn the ParenListExpr into a 4019 // sequence of BinOp comma operators. 4020 Op = MaybeConvertParenListExprToParenExpr(S, move(Op)); 4021 return BuildCStyleCastExpr(LParenLoc, TInfo, RParenLoc, move(Op)); 4022 } 4023} 4024 4025Action::OwningExprResult Sema::ActOnParenOrParenListExpr(SourceLocation L, 4026 SourceLocation R, 4027 MultiExprArg Val, 4028 TypeTy *TypeOfCast) { 4029 unsigned nexprs = Val.size(); 4030 Expr **exprs = reinterpret_cast<Expr**>(Val.release()); 4031 assert((exprs != 0) && "ActOnParenOrParenListExpr() missing expr list"); 4032 Expr *expr; 4033 if (nexprs == 1 && TypeOfCast && !TypeIsVectorType(TypeOfCast)) 4034 expr = new (Context) ParenExpr(L, R, exprs[0]); 4035 else 4036 expr = new (Context) ParenListExpr(Context, L, exprs, nexprs, R); 4037 return Owned(expr); 4038} 4039 4040/// Note that lhs is not null here, even if this is the gnu "x ?: y" extension. 4041/// In that case, lhs = cond. 4042/// C99 6.5.15 4043QualType Sema::CheckConditionalOperands(Expr *&Cond, Expr *&LHS, Expr *&RHS, 4044 SourceLocation QuestionLoc) { 4045 // C++ is sufficiently different to merit its own checker. 4046 if (getLangOptions().CPlusPlus) 4047 return CXXCheckConditionalOperands(Cond, LHS, RHS, QuestionLoc); 4048 4049 CheckSignCompare(LHS, RHS, QuestionLoc); 4050 4051 UsualUnaryConversions(Cond); 4052 UsualUnaryConversions(LHS); 4053 UsualUnaryConversions(RHS); 4054 QualType CondTy = Cond->getType(); 4055 QualType LHSTy = LHS->getType(); 4056 QualType RHSTy = RHS->getType(); 4057 4058 // first, check the condition. 4059 if (!CondTy->isScalarType()) { // C99 6.5.15p2 4060 Diag(Cond->getLocStart(), diag::err_typecheck_cond_expect_scalar) 4061 << CondTy; 4062 return QualType(); 4063 } 4064 4065 // Now check the two expressions. 4066 if (LHSTy->isVectorType() || RHSTy->isVectorType()) 4067 return CheckVectorOperands(QuestionLoc, LHS, RHS); 4068 4069 // If both operands have arithmetic type, do the usual arithmetic conversions 4070 // to find a common type: C99 6.5.15p3,5. 4071 if (LHSTy->isArithmeticType() && RHSTy->isArithmeticType()) { 4072 UsualArithmeticConversions(LHS, RHS); 4073 return LHS->getType(); 4074 } 4075 4076 // If both operands are the same structure or union type, the result is that 4077 // type. 4078 if (const RecordType *LHSRT = LHSTy->getAs<RecordType>()) { // C99 6.5.15p3 4079 if (const RecordType *RHSRT = RHSTy->getAs<RecordType>()) 4080 if (LHSRT->getDecl() == RHSRT->getDecl()) 4081 // "If both the operands have structure or union type, the result has 4082 // that type." This implies that CV qualifiers are dropped. 4083 return LHSTy.getUnqualifiedType(); 4084 // FIXME: Type of conditional expression must be complete in C mode. 4085 } 4086 4087 // C99 6.5.15p5: "If both operands have void type, the result has void type." 4088 // The following || allows only one side to be void (a GCC-ism). 4089 if (LHSTy->isVoidType() || RHSTy->isVoidType()) { 4090 if (!LHSTy->isVoidType()) 4091 Diag(RHS->getLocStart(), diag::ext_typecheck_cond_one_void) 4092 << RHS->getSourceRange(); 4093 if (!RHSTy->isVoidType()) 4094 Diag(LHS->getLocStart(), diag::ext_typecheck_cond_one_void) 4095 << LHS->getSourceRange(); 4096 ImpCastExprToType(LHS, Context.VoidTy, CastExpr::CK_ToVoid); 4097 ImpCastExprToType(RHS, Context.VoidTy, CastExpr::CK_ToVoid); 4098 return Context.VoidTy; 4099 } 4100 // C99 6.5.15p6 - "if one operand is a null pointer constant, the result has 4101 // the type of the other operand." 4102 if ((LHSTy->isAnyPointerType() || LHSTy->isBlockPointerType()) && 4103 RHS->isNullPointerConstant(Context, Expr::NPC_ValueDependentIsNull)) { 4104 // promote the null to a pointer. 4105 ImpCastExprToType(RHS, LHSTy, CastExpr::CK_Unknown); 4106 return LHSTy; 4107 } 4108 if ((RHSTy->isAnyPointerType() || RHSTy->isBlockPointerType()) && 4109 LHS->isNullPointerConstant(Context, Expr::NPC_ValueDependentIsNull)) { 4110 ImpCastExprToType(LHS, RHSTy, CastExpr::CK_Unknown); 4111 return RHSTy; 4112 } 4113 4114 // All objective-c pointer type analysis is done here. 4115 QualType compositeType = FindCompositeObjCPointerType(LHS, RHS, 4116 QuestionLoc); 4117 if (!compositeType.isNull()) 4118 return compositeType; 4119 4120 4121 // Handle block pointer types. 4122 if (LHSTy->isBlockPointerType() || RHSTy->isBlockPointerType()) { 4123 if (!LHSTy->isBlockPointerType() || !RHSTy->isBlockPointerType()) { 4124 if (LHSTy->isVoidPointerType() || RHSTy->isVoidPointerType()) { 4125 QualType destType = Context.getPointerType(Context.VoidTy); 4126 ImpCastExprToType(LHS, destType, CastExpr::CK_BitCast); 4127 ImpCastExprToType(RHS, destType, CastExpr::CK_BitCast); 4128 return destType; 4129 } 4130 Diag(QuestionLoc, diag::err_typecheck_cond_incompatible_operands) 4131 << LHSTy << RHSTy << LHS->getSourceRange() << RHS->getSourceRange(); 4132 return QualType(); 4133 } 4134 // We have 2 block pointer types. 4135 if (Context.getCanonicalType(LHSTy) == Context.getCanonicalType(RHSTy)) { 4136 // Two identical block pointer types are always compatible. 4137 return LHSTy; 4138 } 4139 // The block pointer types aren't identical, continue checking. 4140 QualType lhptee = LHSTy->getAs<BlockPointerType>()->getPointeeType(); 4141 QualType rhptee = RHSTy->getAs<BlockPointerType>()->getPointeeType(); 4142 4143 if (!Context.typesAreCompatible(lhptee.getUnqualifiedType(), 4144 rhptee.getUnqualifiedType())) { 4145 Diag(QuestionLoc, diag::warn_typecheck_cond_incompatible_pointers) 4146 << LHSTy << RHSTy << LHS->getSourceRange() << RHS->getSourceRange(); 4147 // In this situation, we assume void* type. No especially good 4148 // reason, but this is what gcc does, and we do have to pick 4149 // to get a consistent AST. 4150 QualType incompatTy = Context.getPointerType(Context.VoidTy); 4151 ImpCastExprToType(LHS, incompatTy, CastExpr::CK_BitCast); 4152 ImpCastExprToType(RHS, incompatTy, CastExpr::CK_BitCast); 4153 return incompatTy; 4154 } 4155 // The block pointer types are compatible. 4156 ImpCastExprToType(LHS, LHSTy, CastExpr::CK_BitCast); 4157 ImpCastExprToType(RHS, LHSTy, CastExpr::CK_BitCast); 4158 return LHSTy; 4159 } 4160 4161 // Check constraints for C object pointers types (C99 6.5.15p3,6). 4162 if (LHSTy->isPointerType() && RHSTy->isPointerType()) { 4163 // get the "pointed to" types 4164 QualType lhptee = LHSTy->getAs<PointerType>()->getPointeeType(); 4165 QualType rhptee = RHSTy->getAs<PointerType>()->getPointeeType(); 4166 4167 // ignore qualifiers on void (C99 6.5.15p3, clause 6) 4168 if (lhptee->isVoidType() && rhptee->isIncompleteOrObjectType()) { 4169 // Figure out necessary qualifiers (C99 6.5.15p6) 4170 QualType destPointee 4171 = Context.getQualifiedType(lhptee, rhptee.getQualifiers()); 4172 QualType destType = Context.getPointerType(destPointee); 4173 // Add qualifiers if necessary. 4174 ImpCastExprToType(LHS, destType, CastExpr::CK_NoOp); 4175 // Promote to void*. 4176 ImpCastExprToType(RHS, destType, CastExpr::CK_BitCast); 4177 return destType; 4178 } 4179 if (rhptee->isVoidType() && lhptee->isIncompleteOrObjectType()) { 4180 QualType destPointee 4181 = Context.getQualifiedType(rhptee, lhptee.getQualifiers()); 4182 QualType destType = Context.getPointerType(destPointee); 4183 // Add qualifiers if necessary. 4184 ImpCastExprToType(RHS, destType, CastExpr::CK_NoOp); 4185 // Promote to void*. 4186 ImpCastExprToType(LHS, destType, CastExpr::CK_BitCast); 4187 return destType; 4188 } 4189 4190 if (Context.getCanonicalType(LHSTy) == Context.getCanonicalType(RHSTy)) { 4191 // Two identical pointer types are always compatible. 4192 return LHSTy; 4193 } 4194 if (!Context.typesAreCompatible(lhptee.getUnqualifiedType(), 4195 rhptee.getUnqualifiedType())) { 4196 Diag(QuestionLoc, diag::warn_typecheck_cond_incompatible_pointers) 4197 << LHSTy << RHSTy << LHS->getSourceRange() << RHS->getSourceRange(); 4198 // In this situation, we assume void* type. No especially good 4199 // reason, but this is what gcc does, and we do have to pick 4200 // to get a consistent AST. 4201 QualType incompatTy = Context.getPointerType(Context.VoidTy); 4202 ImpCastExprToType(LHS, incompatTy, CastExpr::CK_BitCast); 4203 ImpCastExprToType(RHS, incompatTy, CastExpr::CK_BitCast); 4204 return incompatTy; 4205 } 4206 // The pointer types are compatible. 4207 // C99 6.5.15p6: If both operands are pointers to compatible types *or* to 4208 // differently qualified versions of compatible types, the result type is 4209 // a pointer to an appropriately qualified version of the *composite* 4210 // type. 4211 // FIXME: Need to calculate the composite type. 4212 // FIXME: Need to add qualifiers 4213 ImpCastExprToType(LHS, LHSTy, CastExpr::CK_BitCast); 4214 ImpCastExprToType(RHS, LHSTy, CastExpr::CK_BitCast); 4215 return LHSTy; 4216 } 4217 4218 // GCC compatibility: soften pointer/integer mismatch. 4219 if (RHSTy->isPointerType() && LHSTy->isIntegerType()) { 4220 Diag(QuestionLoc, diag::warn_typecheck_cond_pointer_integer_mismatch) 4221 << LHSTy << RHSTy << LHS->getSourceRange() << RHS->getSourceRange(); 4222 ImpCastExprToType(LHS, RHSTy, CastExpr::CK_IntegralToPointer); 4223 return RHSTy; 4224 } 4225 if (LHSTy->isPointerType() && RHSTy->isIntegerType()) { 4226 Diag(QuestionLoc, diag::warn_typecheck_cond_pointer_integer_mismatch) 4227 << LHSTy << RHSTy << LHS->getSourceRange() << RHS->getSourceRange(); 4228 ImpCastExprToType(RHS, LHSTy, CastExpr::CK_IntegralToPointer); 4229 return LHSTy; 4230 } 4231 4232 // Otherwise, the operands are not compatible. 4233 Diag(QuestionLoc, diag::err_typecheck_cond_incompatible_operands) 4234 << LHSTy << RHSTy << LHS->getSourceRange() << RHS->getSourceRange(); 4235 return QualType(); 4236} 4237 4238/// FindCompositeObjCPointerType - Helper method to find composite type of 4239/// two objective-c pointer types of the two input expressions. 4240QualType Sema::FindCompositeObjCPointerType(Expr *&LHS, Expr *&RHS, 4241 SourceLocation QuestionLoc) { 4242 QualType LHSTy = LHS->getType(); 4243 QualType RHSTy = RHS->getType(); 4244 4245 // Handle things like Class and struct objc_class*. Here we case the result 4246 // to the pseudo-builtin, because that will be implicitly cast back to the 4247 // redefinition type if an attempt is made to access its fields. 4248 if (LHSTy->isObjCClassType() && 4249 (RHSTy.getDesugaredType() == Context.ObjCClassRedefinitionType)) { 4250 ImpCastExprToType(RHS, LHSTy, CastExpr::CK_BitCast); 4251 return LHSTy; 4252 } 4253 if (RHSTy->isObjCClassType() && 4254 (LHSTy.getDesugaredType() == Context.ObjCClassRedefinitionType)) { 4255 ImpCastExprToType(LHS, RHSTy, CastExpr::CK_BitCast); 4256 return RHSTy; 4257 } 4258 // And the same for struct objc_object* / id 4259 if (LHSTy->isObjCIdType() && 4260 (RHSTy.getDesugaredType() == Context.ObjCIdRedefinitionType)) { 4261 ImpCastExprToType(RHS, LHSTy, CastExpr::CK_BitCast); 4262 return LHSTy; 4263 } 4264 if (RHSTy->isObjCIdType() && 4265 (LHSTy.getDesugaredType() == Context.ObjCIdRedefinitionType)) { 4266 ImpCastExprToType(LHS, RHSTy, CastExpr::CK_BitCast); 4267 return RHSTy; 4268 } 4269 // And the same for struct objc_selector* / SEL 4270 if (Context.isObjCSelType(LHSTy) && 4271 (RHSTy.getDesugaredType() == Context.ObjCSelRedefinitionType)) { 4272 ImpCastExprToType(RHS, LHSTy, CastExpr::CK_BitCast); 4273 return LHSTy; 4274 } 4275 if (Context.isObjCSelType(RHSTy) && 4276 (LHSTy.getDesugaredType() == Context.ObjCSelRedefinitionType)) { 4277 ImpCastExprToType(LHS, RHSTy, CastExpr::CK_BitCast); 4278 return RHSTy; 4279 } 4280 // Check constraints for Objective-C object pointers types. 4281 if (LHSTy->isObjCObjectPointerType() && RHSTy->isObjCObjectPointerType()) { 4282 4283 if (Context.getCanonicalType(LHSTy) == Context.getCanonicalType(RHSTy)) { 4284 // Two identical object pointer types are always compatible. 4285 return LHSTy; 4286 } 4287 const ObjCObjectPointerType *LHSOPT = LHSTy->getAs<ObjCObjectPointerType>(); 4288 const ObjCObjectPointerType *RHSOPT = RHSTy->getAs<ObjCObjectPointerType>(); 4289 QualType compositeType = LHSTy; 4290 4291 // If both operands are interfaces and either operand can be 4292 // assigned to the other, use that type as the composite 4293 // type. This allows 4294 // xxx ? (A*) a : (B*) b 4295 // where B is a subclass of A. 4296 // 4297 // Additionally, as for assignment, if either type is 'id' 4298 // allow silent coercion. Finally, if the types are 4299 // incompatible then make sure to use 'id' as the composite 4300 // type so the result is acceptable for sending messages to. 4301 4302 // FIXME: Consider unifying with 'areComparableObjCPointerTypes'. 4303 // It could return the composite type. 4304 if (Context.canAssignObjCInterfaces(LHSOPT, RHSOPT)) { 4305 compositeType = RHSOPT->isObjCBuiltinType() ? RHSTy : LHSTy; 4306 } else if (Context.canAssignObjCInterfaces(RHSOPT, LHSOPT)) { 4307 compositeType = LHSOPT->isObjCBuiltinType() ? LHSTy : RHSTy; 4308 } else if ((LHSTy->isObjCQualifiedIdType() || 4309 RHSTy->isObjCQualifiedIdType()) && 4310 Context.ObjCQualifiedIdTypesAreCompatible(LHSTy, RHSTy, true)) { 4311 // Need to handle "id<xx>" explicitly. 4312 // GCC allows qualified id and any Objective-C type to devolve to 4313 // id. Currently localizing to here until clear this should be 4314 // part of ObjCQualifiedIdTypesAreCompatible. 4315 compositeType = Context.getObjCIdType(); 4316 } else if (LHSTy->isObjCIdType() || RHSTy->isObjCIdType()) { 4317 compositeType = Context.getObjCIdType(); 4318 } else if (!(compositeType = 4319 Context.areCommonBaseCompatible(LHSOPT, RHSOPT)).isNull()) 4320 ; 4321 else { 4322 Diag(QuestionLoc, diag::ext_typecheck_cond_incompatible_operands) 4323 << LHSTy << RHSTy 4324 << LHS->getSourceRange() << RHS->getSourceRange(); 4325 QualType incompatTy = Context.getObjCIdType(); 4326 ImpCastExprToType(LHS, incompatTy, CastExpr::CK_BitCast); 4327 ImpCastExprToType(RHS, incompatTy, CastExpr::CK_BitCast); 4328 return incompatTy; 4329 } 4330 // The object pointer types are compatible. 4331 ImpCastExprToType(LHS, compositeType, CastExpr::CK_BitCast); 4332 ImpCastExprToType(RHS, compositeType, CastExpr::CK_BitCast); 4333 return compositeType; 4334 } 4335 // Check Objective-C object pointer types and 'void *' 4336 if (LHSTy->isVoidPointerType() && RHSTy->isObjCObjectPointerType()) { 4337 QualType lhptee = LHSTy->getAs<PointerType>()->getPointeeType(); 4338 QualType rhptee = RHSTy->getAs<ObjCObjectPointerType>()->getPointeeType(); 4339 QualType destPointee 4340 = Context.getQualifiedType(lhptee, rhptee.getQualifiers()); 4341 QualType destType = Context.getPointerType(destPointee); 4342 // Add qualifiers if necessary. 4343 ImpCastExprToType(LHS, destType, CastExpr::CK_NoOp); 4344 // Promote to void*. 4345 ImpCastExprToType(RHS, destType, CastExpr::CK_BitCast); 4346 return destType; 4347 } 4348 if (LHSTy->isObjCObjectPointerType() && RHSTy->isVoidPointerType()) { 4349 QualType lhptee = LHSTy->getAs<ObjCObjectPointerType>()->getPointeeType(); 4350 QualType rhptee = RHSTy->getAs<PointerType>()->getPointeeType(); 4351 QualType destPointee 4352 = Context.getQualifiedType(rhptee, lhptee.getQualifiers()); 4353 QualType destType = Context.getPointerType(destPointee); 4354 // Add qualifiers if necessary. 4355 ImpCastExprToType(RHS, destType, CastExpr::CK_NoOp); 4356 // Promote to void*. 4357 ImpCastExprToType(LHS, destType, CastExpr::CK_BitCast); 4358 return destType; 4359 } 4360 return QualType(); 4361} 4362 4363/// ActOnConditionalOp - Parse a ?: operation. Note that 'LHS' may be null 4364/// in the case of a the GNU conditional expr extension. 4365Action::OwningExprResult Sema::ActOnConditionalOp(SourceLocation QuestionLoc, 4366 SourceLocation ColonLoc, 4367 ExprArg Cond, ExprArg LHS, 4368 ExprArg RHS) { 4369 Expr *CondExpr = (Expr *) Cond.get(); 4370 Expr *LHSExpr = (Expr *) LHS.get(), *RHSExpr = (Expr *) RHS.get(); 4371 4372 // If this is the gnu "x ?: y" extension, analyze the types as though the LHS 4373 // was the condition. 4374 bool isLHSNull = LHSExpr == 0; 4375 if (isLHSNull) 4376 LHSExpr = CondExpr; 4377 4378 QualType result = CheckConditionalOperands(CondExpr, LHSExpr, 4379 RHSExpr, QuestionLoc); 4380 if (result.isNull()) 4381 return ExprError(); 4382 4383 Cond.release(); 4384 LHS.release(); 4385 RHS.release(); 4386 return Owned(new (Context) ConditionalOperator(CondExpr, QuestionLoc, 4387 isLHSNull ? 0 : LHSExpr, 4388 ColonLoc, RHSExpr, result)); 4389} 4390 4391// CheckPointerTypesForAssignment - This is a very tricky routine (despite 4392// being closely modeled after the C99 spec:-). The odd characteristic of this 4393// routine is it effectively iqnores the qualifiers on the top level pointee. 4394// This circumvents the usual type rules specified in 6.2.7p1 & 6.7.5.[1-3]. 4395// FIXME: add a couple examples in this comment. 4396Sema::AssignConvertType 4397Sema::CheckPointerTypesForAssignment(QualType lhsType, QualType rhsType) { 4398 QualType lhptee, rhptee; 4399 4400 if ((lhsType->isObjCClassType() && 4401 (rhsType.getDesugaredType() == Context.ObjCClassRedefinitionType)) || 4402 (rhsType->isObjCClassType() && 4403 (lhsType.getDesugaredType() == Context.ObjCClassRedefinitionType))) { 4404 return Compatible; 4405 } 4406 4407 // get the "pointed to" type (ignoring qualifiers at the top level) 4408 lhptee = lhsType->getAs<PointerType>()->getPointeeType(); 4409 rhptee = rhsType->getAs<PointerType>()->getPointeeType(); 4410 4411 // make sure we operate on the canonical type 4412 lhptee = Context.getCanonicalType(lhptee); 4413 rhptee = Context.getCanonicalType(rhptee); 4414 4415 AssignConvertType ConvTy = Compatible; 4416 4417 // C99 6.5.16.1p1: This following citation is common to constraints 4418 // 3 & 4 (below). ...and the type *pointed to* by the left has all the 4419 // qualifiers of the type *pointed to* by the right; 4420 // FIXME: Handle ExtQualType 4421 if (!lhptee.isAtLeastAsQualifiedAs(rhptee)) 4422 ConvTy = CompatiblePointerDiscardsQualifiers; 4423 4424 // C99 6.5.16.1p1 (constraint 4): If one operand is a pointer to an object or 4425 // incomplete type and the other is a pointer to a qualified or unqualified 4426 // version of void... 4427 if (lhptee->isVoidType()) { 4428 if (rhptee->isIncompleteOrObjectType()) 4429 return ConvTy; 4430 4431 // As an extension, we allow cast to/from void* to function pointer. 4432 assert(rhptee->isFunctionType()); 4433 return FunctionVoidPointer; 4434 } 4435 4436 if (rhptee->isVoidType()) { 4437 if (lhptee->isIncompleteOrObjectType()) 4438 return ConvTy; 4439 4440 // As an extension, we allow cast to/from void* to function pointer. 4441 assert(lhptee->isFunctionType()); 4442 return FunctionVoidPointer; 4443 } 4444 // C99 6.5.16.1p1 (constraint 3): both operands are pointers to qualified or 4445 // unqualified versions of compatible types, ... 4446 lhptee = lhptee.getUnqualifiedType(); 4447 rhptee = rhptee.getUnqualifiedType(); 4448 if (!Context.typesAreCompatible(lhptee, rhptee)) { 4449 // Check if the pointee types are compatible ignoring the sign. 4450 // We explicitly check for char so that we catch "char" vs 4451 // "unsigned char" on systems where "char" is unsigned. 4452 if (lhptee->isCharType()) 4453 lhptee = Context.UnsignedCharTy; 4454 else if (lhptee->isSignedIntegerType()) 4455 lhptee = Context.getCorrespondingUnsignedType(lhptee); 4456 4457 if (rhptee->isCharType()) 4458 rhptee = Context.UnsignedCharTy; 4459 else if (rhptee->isSignedIntegerType()) 4460 rhptee = Context.getCorrespondingUnsignedType(rhptee); 4461 4462 if (lhptee == rhptee) { 4463 // Types are compatible ignoring the sign. Qualifier incompatibility 4464 // takes priority over sign incompatibility because the sign 4465 // warning can be disabled. 4466 if (ConvTy != Compatible) 4467 return ConvTy; 4468 return IncompatiblePointerSign; 4469 } 4470 4471 // If we are a multi-level pointer, it's possible that our issue is simply 4472 // one of qualification - e.g. char ** -> const char ** is not allowed. If 4473 // the eventual target type is the same and the pointers have the same 4474 // level of indirection, this must be the issue. 4475 if (lhptee->isPointerType() && rhptee->isPointerType()) { 4476 do { 4477 lhptee = lhptee->getAs<PointerType>()->getPointeeType(); 4478 rhptee = rhptee->getAs<PointerType>()->getPointeeType(); 4479 4480 lhptee = Context.getCanonicalType(lhptee); 4481 rhptee = Context.getCanonicalType(rhptee); 4482 } while (lhptee->isPointerType() && rhptee->isPointerType()); 4483 4484 if (Context.hasSameUnqualifiedType(lhptee, rhptee)) 4485 return IncompatibleNestedPointerQualifiers; 4486 } 4487 4488 // General pointer incompatibility takes priority over qualifiers. 4489 return IncompatiblePointer; 4490 } 4491 return ConvTy; 4492} 4493 4494/// CheckBlockPointerTypesForAssignment - This routine determines whether two 4495/// block pointer types are compatible or whether a block and normal pointer 4496/// are compatible. It is more restrict than comparing two function pointer 4497// types. 4498Sema::AssignConvertType 4499Sema::CheckBlockPointerTypesForAssignment(QualType lhsType, 4500 QualType rhsType) { 4501 QualType lhptee, rhptee; 4502 4503 // get the "pointed to" type (ignoring qualifiers at the top level) 4504 lhptee = lhsType->getAs<BlockPointerType>()->getPointeeType(); 4505 rhptee = rhsType->getAs<BlockPointerType>()->getPointeeType(); 4506 4507 // make sure we operate on the canonical type 4508 lhptee = Context.getCanonicalType(lhptee); 4509 rhptee = Context.getCanonicalType(rhptee); 4510 4511 AssignConvertType ConvTy = Compatible; 4512 4513 // For blocks we enforce that qualifiers are identical. 4514 if (lhptee.getLocalCVRQualifiers() != rhptee.getLocalCVRQualifiers()) 4515 ConvTy = CompatiblePointerDiscardsQualifiers; 4516 4517 if (!getLangOptions().CPlusPlus) { 4518 if (!Context.typesAreBlockPointerCompatible(lhsType, rhsType)) 4519 return IncompatibleBlockPointer; 4520 } 4521 else if (!Context.typesAreCompatible(lhptee, rhptee)) 4522 return IncompatibleBlockPointer; 4523 return ConvTy; 4524} 4525 4526/// CheckObjCPointerTypesForAssignment - Compares two objective-c pointer types 4527/// for assignment compatibility. 4528Sema::AssignConvertType 4529Sema::CheckObjCPointerTypesForAssignment(QualType lhsType, QualType rhsType) { 4530 if (lhsType->isObjCBuiltinType()) { 4531 // Class is not compatible with ObjC object pointers. 4532 if (lhsType->isObjCClassType() && !rhsType->isObjCBuiltinType() && 4533 !rhsType->isObjCQualifiedClassType()) 4534 return IncompatiblePointer; 4535 return Compatible; 4536 } 4537 if (rhsType->isObjCBuiltinType()) { 4538 // Class is not compatible with ObjC object pointers. 4539 if (rhsType->isObjCClassType() && !lhsType->isObjCBuiltinType() && 4540 !lhsType->isObjCQualifiedClassType()) 4541 return IncompatiblePointer; 4542 return Compatible; 4543 } 4544 QualType lhptee = 4545 lhsType->getAs<ObjCObjectPointerType>()->getPointeeType(); 4546 QualType rhptee = 4547 rhsType->getAs<ObjCObjectPointerType>()->getPointeeType(); 4548 // make sure we operate on the canonical type 4549 lhptee = Context.getCanonicalType(lhptee); 4550 rhptee = Context.getCanonicalType(rhptee); 4551 if (!lhptee.isAtLeastAsQualifiedAs(rhptee)) 4552 return CompatiblePointerDiscardsQualifiers; 4553 4554 if (Context.typesAreCompatible(lhsType, rhsType)) 4555 return Compatible; 4556 if (lhsType->isObjCQualifiedIdType() || rhsType->isObjCQualifiedIdType()) 4557 return IncompatibleObjCQualifiedId; 4558 return IncompatiblePointer; 4559} 4560 4561/// CheckAssignmentConstraints (C99 6.5.16) - This routine currently 4562/// has code to accommodate several GCC extensions when type checking 4563/// pointers. Here are some objectionable examples that GCC considers warnings: 4564/// 4565/// int a, *pint; 4566/// short *pshort; 4567/// struct foo *pfoo; 4568/// 4569/// pint = pshort; // warning: assignment from incompatible pointer type 4570/// a = pint; // warning: assignment makes integer from pointer without a cast 4571/// pint = a; // warning: assignment makes pointer from integer without a cast 4572/// pint = pfoo; // warning: assignment from incompatible pointer type 4573/// 4574/// As a result, the code for dealing with pointers is more complex than the 4575/// C99 spec dictates. 4576/// 4577Sema::AssignConvertType 4578Sema::CheckAssignmentConstraints(QualType lhsType, QualType rhsType) { 4579 // Get canonical types. We're not formatting these types, just comparing 4580 // them. 4581 lhsType = Context.getCanonicalType(lhsType).getUnqualifiedType(); 4582 rhsType = Context.getCanonicalType(rhsType).getUnqualifiedType(); 4583 4584 if (lhsType == rhsType) 4585 return Compatible; // Common case: fast path an exact match. 4586 4587 if ((lhsType->isObjCClassType() && 4588 (rhsType.getDesugaredType() == Context.ObjCClassRedefinitionType)) || 4589 (rhsType->isObjCClassType() && 4590 (lhsType.getDesugaredType() == Context.ObjCClassRedefinitionType))) { 4591 return Compatible; 4592 } 4593 4594 // If the left-hand side is a reference type, then we are in a 4595 // (rare!) case where we've allowed the use of references in C, 4596 // e.g., as a parameter type in a built-in function. In this case, 4597 // just make sure that the type referenced is compatible with the 4598 // right-hand side type. The caller is responsible for adjusting 4599 // lhsType so that the resulting expression does not have reference 4600 // type. 4601 if (const ReferenceType *lhsTypeRef = lhsType->getAs<ReferenceType>()) { 4602 if (Context.typesAreCompatible(lhsTypeRef->getPointeeType(), rhsType)) 4603 return Compatible; 4604 return Incompatible; 4605 } 4606 // Allow scalar to ExtVector assignments, and assignments of an ExtVector type 4607 // to the same ExtVector type. 4608 if (lhsType->isExtVectorType()) { 4609 if (rhsType->isExtVectorType()) 4610 return lhsType == rhsType ? Compatible : Incompatible; 4611 if (!rhsType->isVectorType() && rhsType->isArithmeticType()) 4612 return Compatible; 4613 } 4614 4615 if (lhsType->isVectorType() || rhsType->isVectorType()) { 4616 // If we are allowing lax vector conversions, and LHS and RHS are both 4617 // vectors, the total size only needs to be the same. This is a bitcast; 4618 // no bits are changed but the result type is different. 4619 if (getLangOptions().LaxVectorConversions && 4620 lhsType->isVectorType() && rhsType->isVectorType()) { 4621 if (Context.getTypeSize(lhsType) == Context.getTypeSize(rhsType)) 4622 return IncompatibleVectors; 4623 } 4624 return Incompatible; 4625 } 4626 4627 if (lhsType->isArithmeticType() && rhsType->isArithmeticType()) 4628 return Compatible; 4629 4630 if (isa<PointerType>(lhsType)) { 4631 if (rhsType->isIntegerType()) 4632 return IntToPointer; 4633 4634 if (isa<PointerType>(rhsType)) 4635 return CheckPointerTypesForAssignment(lhsType, rhsType); 4636 4637 // In general, C pointers are not compatible with ObjC object pointers. 4638 if (isa<ObjCObjectPointerType>(rhsType)) { 4639 if (lhsType->isVoidPointerType()) // an exception to the rule. 4640 return Compatible; 4641 return IncompatiblePointer; 4642 } 4643 if (rhsType->getAs<BlockPointerType>()) { 4644 if (lhsType->getAs<PointerType>()->getPointeeType()->isVoidType()) 4645 return Compatible; 4646 4647 // Treat block pointers as objects. 4648 if (getLangOptions().ObjC1 && lhsType->isObjCIdType()) 4649 return Compatible; 4650 } 4651 return Incompatible; 4652 } 4653 4654 if (isa<BlockPointerType>(lhsType)) { 4655 if (rhsType->isIntegerType()) 4656 return IntToBlockPointer; 4657 4658 // Treat block pointers as objects. 4659 if (getLangOptions().ObjC1 && rhsType->isObjCIdType()) 4660 return Compatible; 4661 4662 if (rhsType->isBlockPointerType()) 4663 return CheckBlockPointerTypesForAssignment(lhsType, rhsType); 4664 4665 if (const PointerType *RHSPT = rhsType->getAs<PointerType>()) { 4666 if (RHSPT->getPointeeType()->isVoidType()) 4667 return Compatible; 4668 } 4669 return Incompatible; 4670 } 4671 4672 if (isa<ObjCObjectPointerType>(lhsType)) { 4673 if (rhsType->isIntegerType()) 4674 return IntToPointer; 4675 4676 // In general, C pointers are not compatible with ObjC object pointers. 4677 if (isa<PointerType>(rhsType)) { 4678 if (rhsType->isVoidPointerType()) // an exception to the rule. 4679 return Compatible; 4680 return IncompatiblePointer; 4681 } 4682 if (rhsType->isObjCObjectPointerType()) { 4683 return CheckObjCPointerTypesForAssignment(lhsType, rhsType); 4684 } 4685 if (const PointerType *RHSPT = rhsType->getAs<PointerType>()) { 4686 if (RHSPT->getPointeeType()->isVoidType()) 4687 return Compatible; 4688 } 4689 // Treat block pointers as objects. 4690 if (rhsType->isBlockPointerType()) 4691 return Compatible; 4692 return Incompatible; 4693 } 4694 if (isa<PointerType>(rhsType)) { 4695 // C99 6.5.16.1p1: the left operand is _Bool and the right is a pointer. 4696 if (lhsType == Context.BoolTy) 4697 return Compatible; 4698 4699 if (lhsType->isIntegerType()) 4700 return PointerToInt; 4701 4702 if (isa<PointerType>(lhsType)) 4703 return CheckPointerTypesForAssignment(lhsType, rhsType); 4704 4705 if (isa<BlockPointerType>(lhsType) && 4706 rhsType->getAs<PointerType>()->getPointeeType()->isVoidType()) 4707 return Compatible; 4708 return Incompatible; 4709 } 4710 if (isa<ObjCObjectPointerType>(rhsType)) { 4711 // C99 6.5.16.1p1: the left operand is _Bool and the right is a pointer. 4712 if (lhsType == Context.BoolTy) 4713 return Compatible; 4714 4715 if (lhsType->isIntegerType()) 4716 return PointerToInt; 4717 4718 // In general, C pointers are not compatible with ObjC object pointers. 4719 if (isa<PointerType>(lhsType)) { 4720 if (lhsType->isVoidPointerType()) // an exception to the rule. 4721 return Compatible; 4722 return IncompatiblePointer; 4723 } 4724 if (isa<BlockPointerType>(lhsType) && 4725 rhsType->getAs<PointerType>()->getPointeeType()->isVoidType()) 4726 return Compatible; 4727 return Incompatible; 4728 } 4729 4730 if (isa<TagType>(lhsType) && isa<TagType>(rhsType)) { 4731 if (Context.typesAreCompatible(lhsType, rhsType)) 4732 return Compatible; 4733 } 4734 return Incompatible; 4735} 4736 4737/// \brief Constructs a transparent union from an expression that is 4738/// used to initialize the transparent union. 4739static void ConstructTransparentUnion(ASTContext &C, Expr *&E, 4740 QualType UnionType, FieldDecl *Field) { 4741 // Build an initializer list that designates the appropriate member 4742 // of the transparent union. 4743 InitListExpr *Initializer = new (C) InitListExpr(C, SourceLocation(), 4744 &E, 1, 4745 SourceLocation()); 4746 Initializer->setType(UnionType); 4747 Initializer->setInitializedFieldInUnion(Field); 4748 4749 // Build a compound literal constructing a value of the transparent 4750 // union type from this initializer list. 4751 TypeSourceInfo *unionTInfo = C.getTrivialTypeSourceInfo(UnionType); 4752 E = new (C) CompoundLiteralExpr(SourceLocation(), unionTInfo, UnionType, 4753 Initializer, false); 4754} 4755 4756Sema::AssignConvertType 4757Sema::CheckTransparentUnionArgumentConstraints(QualType ArgType, Expr *&rExpr) { 4758 QualType FromType = rExpr->getType(); 4759 4760 // If the ArgType is a Union type, we want to handle a potential 4761 // transparent_union GCC extension. 4762 const RecordType *UT = ArgType->getAsUnionType(); 4763 if (!UT || !UT->getDecl()->hasAttr<TransparentUnionAttr>()) 4764 return Incompatible; 4765 4766 // The field to initialize within the transparent union. 4767 RecordDecl *UD = UT->getDecl(); 4768 FieldDecl *InitField = 0; 4769 // It's compatible if the expression matches any of the fields. 4770 for (RecordDecl::field_iterator it = UD->field_begin(), 4771 itend = UD->field_end(); 4772 it != itend; ++it) { 4773 if (it->getType()->isPointerType()) { 4774 // If the transparent union contains a pointer type, we allow: 4775 // 1) void pointer 4776 // 2) null pointer constant 4777 if (FromType->isPointerType()) 4778 if (FromType->getAs<PointerType>()->getPointeeType()->isVoidType()) { 4779 ImpCastExprToType(rExpr, it->getType(), CastExpr::CK_BitCast); 4780 InitField = *it; 4781 break; 4782 } 4783 4784 if (rExpr->isNullPointerConstant(Context, 4785 Expr::NPC_ValueDependentIsNull)) { 4786 ImpCastExprToType(rExpr, it->getType(), CastExpr::CK_IntegralToPointer); 4787 InitField = *it; 4788 break; 4789 } 4790 } 4791 4792 if (CheckAssignmentConstraints(it->getType(), rExpr->getType()) 4793 == Compatible) { 4794 InitField = *it; 4795 break; 4796 } 4797 } 4798 4799 if (!InitField) 4800 return Incompatible; 4801 4802 ConstructTransparentUnion(Context, rExpr, ArgType, InitField); 4803 return Compatible; 4804} 4805 4806Sema::AssignConvertType 4807Sema::CheckSingleAssignmentConstraints(QualType lhsType, Expr *&rExpr) { 4808 if (getLangOptions().CPlusPlus) { 4809 if (!lhsType->isRecordType()) { 4810 // C++ 5.17p3: If the left operand is not of class type, the 4811 // expression is implicitly converted (C++ 4) to the 4812 // cv-unqualified type of the left operand. 4813 if (PerformImplicitConversion(rExpr, lhsType.getUnqualifiedType(), 4814 AA_Assigning)) 4815 return Incompatible; 4816 return Compatible; 4817 } 4818 4819 // FIXME: Currently, we fall through and treat C++ classes like C 4820 // structures. 4821 } 4822 4823 // C99 6.5.16.1p1: the left operand is a pointer and the right is 4824 // a null pointer constant. 4825 if ((lhsType->isPointerType() || 4826 lhsType->isObjCObjectPointerType() || 4827 lhsType->isBlockPointerType()) 4828 && rExpr->isNullPointerConstant(Context, 4829 Expr::NPC_ValueDependentIsNull)) { 4830 ImpCastExprToType(rExpr, lhsType, CastExpr::CK_Unknown); 4831 return Compatible; 4832 } 4833 4834 // This check seems unnatural, however it is necessary to ensure the proper 4835 // conversion of functions/arrays. If the conversion were done for all 4836 // DeclExpr's (created by ActOnIdExpression), it would mess up the unary 4837 // expressions that surpress this implicit conversion (&, sizeof). 4838 // 4839 // Suppress this for references: C++ 8.5.3p5. 4840 if (!lhsType->isReferenceType()) 4841 DefaultFunctionArrayLvalueConversion(rExpr); 4842 4843 Sema::AssignConvertType result = 4844 CheckAssignmentConstraints(lhsType, rExpr->getType()); 4845 4846 // C99 6.5.16.1p2: The value of the right operand is converted to the 4847 // type of the assignment expression. 4848 // CheckAssignmentConstraints allows the left-hand side to be a reference, 4849 // so that we can use references in built-in functions even in C. 4850 // The getNonReferenceType() call makes sure that the resulting expression 4851 // does not have reference type. 4852 if (result != Incompatible && rExpr->getType() != lhsType) 4853 ImpCastExprToType(rExpr, lhsType.getNonReferenceType(), 4854 CastExpr::CK_Unknown); 4855 return result; 4856} 4857 4858QualType Sema::InvalidOperands(SourceLocation Loc, Expr *&lex, Expr *&rex) { 4859 Diag(Loc, diag::err_typecheck_invalid_operands) 4860 << lex->getType() << rex->getType() 4861 << lex->getSourceRange() << rex->getSourceRange(); 4862 return QualType(); 4863} 4864 4865QualType Sema::CheckVectorOperands(SourceLocation Loc, Expr *&lex, Expr *&rex) { 4866 // For conversion purposes, we ignore any qualifiers. 4867 // For example, "const float" and "float" are equivalent. 4868 QualType lhsType = 4869 Context.getCanonicalType(lex->getType()).getUnqualifiedType(); 4870 QualType rhsType = 4871 Context.getCanonicalType(rex->getType()).getUnqualifiedType(); 4872 4873 // If the vector types are identical, return. 4874 if (lhsType == rhsType) 4875 return lhsType; 4876 4877 // Handle the case of a vector & extvector type of the same size and element 4878 // type. It would be nice if we only had one vector type someday. 4879 if (getLangOptions().LaxVectorConversions) { 4880 // FIXME: Should we warn here? 4881 if (const VectorType *LV = lhsType->getAs<VectorType>()) { 4882 if (const VectorType *RV = rhsType->getAs<VectorType>()) 4883 if (LV->getElementType() == RV->getElementType() && 4884 LV->getNumElements() == RV->getNumElements()) { 4885 return lhsType->isExtVectorType() ? lhsType : rhsType; 4886 } 4887 } 4888 } 4889 4890 // Canonicalize the ExtVector to the LHS, remember if we swapped so we can 4891 // swap back (so that we don't reverse the inputs to a subtract, for instance. 4892 bool swapped = false; 4893 if (rhsType->isExtVectorType()) { 4894 swapped = true; 4895 std::swap(rex, lex); 4896 std::swap(rhsType, lhsType); 4897 } 4898 4899 // Handle the case of an ext vector and scalar. 4900 if (const ExtVectorType *LV = lhsType->getAs<ExtVectorType>()) { 4901 QualType EltTy = LV->getElementType(); 4902 if (EltTy->isIntegralType() && rhsType->isIntegralType()) { 4903 if (Context.getIntegerTypeOrder(EltTy, rhsType) >= 0) { 4904 ImpCastExprToType(rex, lhsType, CastExpr::CK_IntegralCast); 4905 if (swapped) std::swap(rex, lex); 4906 return lhsType; 4907 } 4908 } 4909 if (EltTy->isRealFloatingType() && rhsType->isScalarType() && 4910 rhsType->isRealFloatingType()) { 4911 if (Context.getFloatingTypeOrder(EltTy, rhsType) >= 0) { 4912 ImpCastExprToType(rex, lhsType, CastExpr::CK_FloatingCast); 4913 if (swapped) std::swap(rex, lex); 4914 return lhsType; 4915 } 4916 } 4917 } 4918 4919 // Vectors of different size or scalar and non-ext-vector are errors. 4920 Diag(Loc, diag::err_typecheck_vector_not_convertable) 4921 << lex->getType() << rex->getType() 4922 << lex->getSourceRange() << rex->getSourceRange(); 4923 return QualType(); 4924} 4925 4926QualType Sema::CheckMultiplyDivideOperands( 4927 Expr *&lex, Expr *&rex, SourceLocation Loc, bool isCompAssign, bool isDiv) { 4928 if (lex->getType()->isVectorType() || rex->getType()->isVectorType()) 4929 return CheckVectorOperands(Loc, lex, rex); 4930 4931 QualType compType = UsualArithmeticConversions(lex, rex, isCompAssign); 4932 4933 if (!lex->getType()->isArithmeticType() || 4934 !rex->getType()->isArithmeticType()) 4935 return InvalidOperands(Loc, lex, rex); 4936 4937 // Check for division by zero. 4938 if (isDiv && 4939 rex->isNullPointerConstant(Context, Expr::NPC_ValueDependentIsNotNull)) 4940 DiagRuntimeBehavior(Loc, PDiag(diag::warn_division_by_zero) 4941 << rex->getSourceRange()); 4942 4943 return compType; 4944} 4945 4946QualType Sema::CheckRemainderOperands( 4947 Expr *&lex, Expr *&rex, SourceLocation Loc, bool isCompAssign) { 4948 if (lex->getType()->isVectorType() || rex->getType()->isVectorType()) { 4949 if (lex->getType()->isIntegerType() && rex->getType()->isIntegerType()) 4950 return CheckVectorOperands(Loc, lex, rex); 4951 return InvalidOperands(Loc, lex, rex); 4952 } 4953 4954 QualType compType = UsualArithmeticConversions(lex, rex, isCompAssign); 4955 4956 if (!lex->getType()->isIntegerType() || !rex->getType()->isIntegerType()) 4957 return InvalidOperands(Loc, lex, rex); 4958 4959 // Check for remainder by zero. 4960 if (rex->isNullPointerConstant(Context, Expr::NPC_ValueDependentIsNotNull)) 4961 DiagRuntimeBehavior(Loc, PDiag(diag::warn_remainder_by_zero) 4962 << rex->getSourceRange()); 4963 4964 return compType; 4965} 4966 4967QualType Sema::CheckAdditionOperands( // C99 6.5.6 4968 Expr *&lex, Expr *&rex, SourceLocation Loc, QualType* CompLHSTy) { 4969 if (lex->getType()->isVectorType() || rex->getType()->isVectorType()) { 4970 QualType compType = CheckVectorOperands(Loc, lex, rex); 4971 if (CompLHSTy) *CompLHSTy = compType; 4972 return compType; 4973 } 4974 4975 QualType compType = UsualArithmeticConversions(lex, rex, CompLHSTy); 4976 4977 // handle the common case first (both operands are arithmetic). 4978 if (lex->getType()->isArithmeticType() && 4979 rex->getType()->isArithmeticType()) { 4980 if (CompLHSTy) *CompLHSTy = compType; 4981 return compType; 4982 } 4983 4984 // Put any potential pointer into PExp 4985 Expr* PExp = lex, *IExp = rex; 4986 if (IExp->getType()->isAnyPointerType()) 4987 std::swap(PExp, IExp); 4988 4989 if (PExp->getType()->isAnyPointerType()) { 4990 4991 if (IExp->getType()->isIntegerType()) { 4992 QualType PointeeTy = PExp->getType()->getPointeeType(); 4993 4994 // Check for arithmetic on pointers to incomplete types. 4995 if (PointeeTy->isVoidType()) { 4996 if (getLangOptions().CPlusPlus) { 4997 Diag(Loc, diag::err_typecheck_pointer_arith_void_type) 4998 << lex->getSourceRange() << rex->getSourceRange(); 4999 return QualType(); 5000 } 5001 5002 // GNU extension: arithmetic on pointer to void 5003 Diag(Loc, diag::ext_gnu_void_ptr) 5004 << lex->getSourceRange() << rex->getSourceRange(); 5005 } else if (PointeeTy->isFunctionType()) { 5006 if (getLangOptions().CPlusPlus) { 5007 Diag(Loc, diag::err_typecheck_pointer_arith_function_type) 5008 << lex->getType() << lex->getSourceRange(); 5009 return QualType(); 5010 } 5011 5012 // GNU extension: arithmetic on pointer to function 5013 Diag(Loc, diag::ext_gnu_ptr_func_arith) 5014 << lex->getType() << lex->getSourceRange(); 5015 } else { 5016 // Check if we require a complete type. 5017 if (((PExp->getType()->isPointerType() && 5018 !PExp->getType()->isDependentType()) || 5019 PExp->getType()->isObjCObjectPointerType()) && 5020 RequireCompleteType(Loc, PointeeTy, 5021 PDiag(diag::err_typecheck_arithmetic_incomplete_type) 5022 << PExp->getSourceRange() 5023 << PExp->getType())) 5024 return QualType(); 5025 } 5026 // Diagnose bad cases where we step over interface counts. 5027 if (PointeeTy->isObjCInterfaceType() && LangOpts.ObjCNonFragileABI) { 5028 Diag(Loc, diag::err_arithmetic_nonfragile_interface) 5029 << PointeeTy << PExp->getSourceRange(); 5030 return QualType(); 5031 } 5032 5033 if (CompLHSTy) { 5034 QualType LHSTy = Context.isPromotableBitField(lex); 5035 if (LHSTy.isNull()) { 5036 LHSTy = lex->getType(); 5037 if (LHSTy->isPromotableIntegerType()) 5038 LHSTy = Context.getPromotedIntegerType(LHSTy); 5039 } 5040 *CompLHSTy = LHSTy; 5041 } 5042 return PExp->getType(); 5043 } 5044 } 5045 5046 return InvalidOperands(Loc, lex, rex); 5047} 5048 5049// C99 6.5.6 5050QualType Sema::CheckSubtractionOperands(Expr *&lex, Expr *&rex, 5051 SourceLocation Loc, QualType* CompLHSTy) { 5052 if (lex->getType()->isVectorType() || rex->getType()->isVectorType()) { 5053 QualType compType = CheckVectorOperands(Loc, lex, rex); 5054 if (CompLHSTy) *CompLHSTy = compType; 5055 return compType; 5056 } 5057 5058 QualType compType = UsualArithmeticConversions(lex, rex, CompLHSTy); 5059 5060 // Enforce type constraints: C99 6.5.6p3. 5061 5062 // Handle the common case first (both operands are arithmetic). 5063 if (lex->getType()->isArithmeticType() 5064 && rex->getType()->isArithmeticType()) { 5065 if (CompLHSTy) *CompLHSTy = compType; 5066 return compType; 5067 } 5068 5069 // Either ptr - int or ptr - ptr. 5070 if (lex->getType()->isAnyPointerType()) { 5071 QualType lpointee = lex->getType()->getPointeeType(); 5072 5073 // The LHS must be an completely-defined object type. 5074 5075 bool ComplainAboutVoid = false; 5076 Expr *ComplainAboutFunc = 0; 5077 if (lpointee->isVoidType()) { 5078 if (getLangOptions().CPlusPlus) { 5079 Diag(Loc, diag::err_typecheck_pointer_arith_void_type) 5080 << lex->getSourceRange() << rex->getSourceRange(); 5081 return QualType(); 5082 } 5083 5084 // GNU C extension: arithmetic on pointer to void 5085 ComplainAboutVoid = true; 5086 } else if (lpointee->isFunctionType()) { 5087 if (getLangOptions().CPlusPlus) { 5088 Diag(Loc, diag::err_typecheck_pointer_arith_function_type) 5089 << lex->getType() << lex->getSourceRange(); 5090 return QualType(); 5091 } 5092 5093 // GNU C extension: arithmetic on pointer to function 5094 ComplainAboutFunc = lex; 5095 } else if (!lpointee->isDependentType() && 5096 RequireCompleteType(Loc, lpointee, 5097 PDiag(diag::err_typecheck_sub_ptr_object) 5098 << lex->getSourceRange() 5099 << lex->getType())) 5100 return QualType(); 5101 5102 // Diagnose bad cases where we step over interface counts. 5103 if (lpointee->isObjCInterfaceType() && LangOpts.ObjCNonFragileABI) { 5104 Diag(Loc, diag::err_arithmetic_nonfragile_interface) 5105 << lpointee << lex->getSourceRange(); 5106 return QualType(); 5107 } 5108 5109 // The result type of a pointer-int computation is the pointer type. 5110 if (rex->getType()->isIntegerType()) { 5111 if (ComplainAboutVoid) 5112 Diag(Loc, diag::ext_gnu_void_ptr) 5113 << lex->getSourceRange() << rex->getSourceRange(); 5114 if (ComplainAboutFunc) 5115 Diag(Loc, diag::ext_gnu_ptr_func_arith) 5116 << ComplainAboutFunc->getType() 5117 << ComplainAboutFunc->getSourceRange(); 5118 5119 if (CompLHSTy) *CompLHSTy = lex->getType(); 5120 return lex->getType(); 5121 } 5122 5123 // Handle pointer-pointer subtractions. 5124 if (const PointerType *RHSPTy = rex->getType()->getAs<PointerType>()) { 5125 QualType rpointee = RHSPTy->getPointeeType(); 5126 5127 // RHS must be a completely-type object type. 5128 // Handle the GNU void* extension. 5129 if (rpointee->isVoidType()) { 5130 if (getLangOptions().CPlusPlus) { 5131 Diag(Loc, diag::err_typecheck_pointer_arith_void_type) 5132 << lex->getSourceRange() << rex->getSourceRange(); 5133 return QualType(); 5134 } 5135 5136 ComplainAboutVoid = true; 5137 } else if (rpointee->isFunctionType()) { 5138 if (getLangOptions().CPlusPlus) { 5139 Diag(Loc, diag::err_typecheck_pointer_arith_function_type) 5140 << rex->getType() << rex->getSourceRange(); 5141 return QualType(); 5142 } 5143 5144 // GNU extension: arithmetic on pointer to function 5145 if (!ComplainAboutFunc) 5146 ComplainAboutFunc = rex; 5147 } else if (!rpointee->isDependentType() && 5148 RequireCompleteType(Loc, rpointee, 5149 PDiag(diag::err_typecheck_sub_ptr_object) 5150 << rex->getSourceRange() 5151 << rex->getType())) 5152 return QualType(); 5153 5154 if (getLangOptions().CPlusPlus) { 5155 // Pointee types must be the same: C++ [expr.add] 5156 if (!Context.hasSameUnqualifiedType(lpointee, rpointee)) { 5157 Diag(Loc, diag::err_typecheck_sub_ptr_compatible) 5158 << lex->getType() << rex->getType() 5159 << lex->getSourceRange() << rex->getSourceRange(); 5160 return QualType(); 5161 } 5162 } else { 5163 // Pointee types must be compatible C99 6.5.6p3 5164 if (!Context.typesAreCompatible( 5165 Context.getCanonicalType(lpointee).getUnqualifiedType(), 5166 Context.getCanonicalType(rpointee).getUnqualifiedType())) { 5167 Diag(Loc, diag::err_typecheck_sub_ptr_compatible) 5168 << lex->getType() << rex->getType() 5169 << lex->getSourceRange() << rex->getSourceRange(); 5170 return QualType(); 5171 } 5172 } 5173 5174 if (ComplainAboutVoid) 5175 Diag(Loc, diag::ext_gnu_void_ptr) 5176 << lex->getSourceRange() << rex->getSourceRange(); 5177 if (ComplainAboutFunc) 5178 Diag(Loc, diag::ext_gnu_ptr_func_arith) 5179 << ComplainAboutFunc->getType() 5180 << ComplainAboutFunc->getSourceRange(); 5181 5182 if (CompLHSTy) *CompLHSTy = lex->getType(); 5183 return Context.getPointerDiffType(); 5184 } 5185 } 5186 5187 return InvalidOperands(Loc, lex, rex); 5188} 5189 5190// C99 6.5.7 5191QualType Sema::CheckShiftOperands(Expr *&lex, Expr *&rex, SourceLocation Loc, 5192 bool isCompAssign) { 5193 // C99 6.5.7p2: Each of the operands shall have integer type. 5194 if (!lex->getType()->isIntegerType() || !rex->getType()->isIntegerType()) 5195 return InvalidOperands(Loc, lex, rex); 5196 5197 // Vector shifts promote their scalar inputs to vector type. 5198 if (lex->getType()->isVectorType() || rex->getType()->isVectorType()) 5199 return CheckVectorOperands(Loc, lex, rex); 5200 5201 // Shifts don't perform usual arithmetic conversions, they just do integer 5202 // promotions on each operand. C99 6.5.7p3 5203 QualType LHSTy = Context.isPromotableBitField(lex); 5204 if (LHSTy.isNull()) { 5205 LHSTy = lex->getType(); 5206 if (LHSTy->isPromotableIntegerType()) 5207 LHSTy = Context.getPromotedIntegerType(LHSTy); 5208 } 5209 if (!isCompAssign) 5210 ImpCastExprToType(lex, LHSTy, CastExpr::CK_IntegralCast); 5211 5212 UsualUnaryConversions(rex); 5213 5214 // Sanity-check shift operands 5215 llvm::APSInt Right; 5216 // Check right/shifter operand 5217 if (!rex->isValueDependent() && 5218 rex->isIntegerConstantExpr(Right, Context)) { 5219 if (Right.isNegative()) 5220 Diag(Loc, diag::warn_shift_negative) << rex->getSourceRange(); 5221 else { 5222 llvm::APInt LeftBits(Right.getBitWidth(), 5223 Context.getTypeSize(lex->getType())); 5224 if (Right.uge(LeftBits)) 5225 Diag(Loc, diag::warn_shift_gt_typewidth) << rex->getSourceRange(); 5226 } 5227 } 5228 5229 // "The type of the result is that of the promoted left operand." 5230 return LHSTy; 5231} 5232 5233// C99 6.5.8, C++ [expr.rel] 5234QualType Sema::CheckCompareOperands(Expr *&lex, Expr *&rex, SourceLocation Loc, 5235 unsigned OpaqueOpc, bool isRelational) { 5236 BinaryOperator::Opcode Opc = (BinaryOperator::Opcode)OpaqueOpc; 5237 5238 // Handle vector comparisons separately. 5239 if (lex->getType()->isVectorType() || rex->getType()->isVectorType()) 5240 return CheckVectorCompareOperands(lex, rex, Loc, isRelational); 5241 5242 CheckSignCompare(lex, rex, Loc, &Opc); 5243 5244 // C99 6.5.8p3 / C99 6.5.9p4 5245 if (lex->getType()->isArithmeticType() && rex->getType()->isArithmeticType()) 5246 UsualArithmeticConversions(lex, rex); 5247 else { 5248 UsualUnaryConversions(lex); 5249 UsualUnaryConversions(rex); 5250 } 5251 QualType lType = lex->getType(); 5252 QualType rType = rex->getType(); 5253 5254 if (!lType->isFloatingType() 5255 && !(lType->isBlockPointerType() && isRelational)) { 5256 // For non-floating point types, check for self-comparisons of the form 5257 // x == x, x != x, x < x, etc. These always evaluate to a constant, and 5258 // often indicate logic errors in the program. 5259 // NOTE: Don't warn about comparisons of enum constants. These can arise 5260 // from macro expansions, and are usually quite deliberate. 5261 Expr *LHSStripped = lex->IgnoreParens(); 5262 Expr *RHSStripped = rex->IgnoreParens(); 5263 if (DeclRefExpr* DRL = dyn_cast<DeclRefExpr>(LHSStripped)) 5264 if (DeclRefExpr* DRR = dyn_cast<DeclRefExpr>(RHSStripped)) 5265 if (DRL->getDecl() == DRR->getDecl() && 5266 !isa<EnumConstantDecl>(DRL->getDecl())) 5267 DiagRuntimeBehavior(Loc, PDiag(diag::warn_selfcomparison)); 5268 5269 if (isa<CastExpr>(LHSStripped)) 5270 LHSStripped = LHSStripped->IgnoreParenCasts(); 5271 if (isa<CastExpr>(RHSStripped)) 5272 RHSStripped = RHSStripped->IgnoreParenCasts(); 5273 5274 // Warn about comparisons against a string constant (unless the other 5275 // operand is null), the user probably wants strcmp. 5276 Expr *literalString = 0; 5277 Expr *literalStringStripped = 0; 5278 if ((isa<StringLiteral>(LHSStripped) || isa<ObjCEncodeExpr>(LHSStripped)) && 5279 !RHSStripped->isNullPointerConstant(Context, 5280 Expr::NPC_ValueDependentIsNull)) { 5281 literalString = lex; 5282 literalStringStripped = LHSStripped; 5283 } else if ((isa<StringLiteral>(RHSStripped) || 5284 isa<ObjCEncodeExpr>(RHSStripped)) && 5285 !LHSStripped->isNullPointerConstant(Context, 5286 Expr::NPC_ValueDependentIsNull)) { 5287 literalString = rex; 5288 literalStringStripped = RHSStripped; 5289 } 5290 5291 if (literalString) { 5292 std::string resultComparison; 5293 switch (Opc) { 5294 case BinaryOperator::LT: resultComparison = ") < 0"; break; 5295 case BinaryOperator::GT: resultComparison = ") > 0"; break; 5296 case BinaryOperator::LE: resultComparison = ") <= 0"; break; 5297 case BinaryOperator::GE: resultComparison = ") >= 0"; break; 5298 case BinaryOperator::EQ: resultComparison = ") == 0"; break; 5299 case BinaryOperator::NE: resultComparison = ") != 0"; break; 5300 default: assert(false && "Invalid comparison operator"); 5301 } 5302 5303 DiagRuntimeBehavior(Loc, 5304 PDiag(diag::warn_stringcompare) 5305 << isa<ObjCEncodeExpr>(literalStringStripped) 5306 << literalString->getSourceRange()); 5307 } 5308 } 5309 5310 // The result of comparisons is 'bool' in C++, 'int' in C. 5311 QualType ResultTy = getLangOptions().CPlusPlus ? Context.BoolTy:Context.IntTy; 5312 5313 if (isRelational) { 5314 if (lType->isRealType() && rType->isRealType()) 5315 return ResultTy; 5316 } else { 5317 // Check for comparisons of floating point operands using != and ==. 5318 if (lType->isFloatingType() && rType->isFloatingType()) 5319 CheckFloatComparison(Loc,lex,rex); 5320 5321 if (lType->isArithmeticType() && rType->isArithmeticType()) 5322 return ResultTy; 5323 } 5324 5325 bool LHSIsNull = lex->isNullPointerConstant(Context, 5326 Expr::NPC_ValueDependentIsNull); 5327 bool RHSIsNull = rex->isNullPointerConstant(Context, 5328 Expr::NPC_ValueDependentIsNull); 5329 5330 // All of the following pointer related warnings are GCC extensions, except 5331 // when handling null pointer constants. One day, we can consider making them 5332 // errors (when -pedantic-errors is enabled). 5333 if (lType->isPointerType() && rType->isPointerType()) { // C99 6.5.8p2 5334 QualType LCanPointeeTy = 5335 Context.getCanonicalType(lType->getAs<PointerType>()->getPointeeType()); 5336 QualType RCanPointeeTy = 5337 Context.getCanonicalType(rType->getAs<PointerType>()->getPointeeType()); 5338 5339 if (getLangOptions().CPlusPlus) { 5340 if (LCanPointeeTy == RCanPointeeTy) 5341 return ResultTy; 5342 if (!isRelational && 5343 (LCanPointeeTy->isVoidType() || RCanPointeeTy->isVoidType())) { 5344 // Valid unless comparison between non-null pointer and function pointer 5345 // This is a gcc extension compatibility comparison. 5346 if ((LCanPointeeTy->isFunctionType() || RCanPointeeTy->isFunctionType()) 5347 && !LHSIsNull && !RHSIsNull) { 5348 Diag(Loc, diag::ext_typecheck_comparison_of_fptr_to_void) 5349 << lType << rType << lex->getSourceRange() << rex->getSourceRange(); 5350 ImpCastExprToType(rex, lType, CastExpr::CK_BitCast); 5351 return ResultTy; 5352 } 5353 } 5354 // C++ [expr.rel]p2: 5355 // [...] Pointer conversions (4.10) and qualification 5356 // conversions (4.4) are performed on pointer operands (or on 5357 // a pointer operand and a null pointer constant) to bring 5358 // them to their composite pointer type. [...] 5359 // 5360 // C++ [expr.eq]p1 uses the same notion for (in)equality 5361 // comparisons of pointers. 5362 bool NonStandardCompositeType = false; 5363 QualType T = FindCompositePointerType(Loc, lex, rex, 5364 isSFINAEContext()? 0 : &NonStandardCompositeType); 5365 if (T.isNull()) { 5366 Diag(Loc, diag::err_typecheck_comparison_of_distinct_pointers) 5367 << lType << rType << lex->getSourceRange() << rex->getSourceRange(); 5368 return QualType(); 5369 } else if (NonStandardCompositeType) { 5370 Diag(Loc, 5371 diag::ext_typecheck_comparison_of_distinct_pointers_nonstandard) 5372 << lType << rType << T 5373 << lex->getSourceRange() << rex->getSourceRange(); 5374 } 5375 5376 ImpCastExprToType(lex, T, CastExpr::CK_BitCast); 5377 ImpCastExprToType(rex, T, CastExpr::CK_BitCast); 5378 return ResultTy; 5379 } 5380 // C99 6.5.9p2 and C99 6.5.8p2 5381 if (Context.typesAreCompatible(LCanPointeeTy.getUnqualifiedType(), 5382 RCanPointeeTy.getUnqualifiedType())) { 5383 // Valid unless a relational comparison of function pointers 5384 if (isRelational && LCanPointeeTy->isFunctionType()) { 5385 Diag(Loc, diag::ext_typecheck_ordered_comparison_of_function_pointers) 5386 << lType << rType << lex->getSourceRange() << rex->getSourceRange(); 5387 } 5388 } else if (!isRelational && 5389 (LCanPointeeTy->isVoidType() || RCanPointeeTy->isVoidType())) { 5390 // Valid unless comparison between non-null pointer and function pointer 5391 if ((LCanPointeeTy->isFunctionType() || RCanPointeeTy->isFunctionType()) 5392 && !LHSIsNull && !RHSIsNull) { 5393 Diag(Loc, diag::ext_typecheck_comparison_of_fptr_to_void) 5394 << lType << rType << lex->getSourceRange() << rex->getSourceRange(); 5395 } 5396 } else { 5397 // Invalid 5398 Diag(Loc, diag::ext_typecheck_comparison_of_distinct_pointers) 5399 << lType << rType << lex->getSourceRange() << rex->getSourceRange(); 5400 } 5401 if (LCanPointeeTy != RCanPointeeTy) 5402 ImpCastExprToType(rex, lType, CastExpr::CK_BitCast); 5403 return ResultTy; 5404 } 5405 5406 if (getLangOptions().CPlusPlus) { 5407 // Comparison of pointers with null pointer constants and equality 5408 // comparisons of member pointers to null pointer constants. 5409 if (RHSIsNull && 5410 (lType->isPointerType() || 5411 (!isRelational && lType->isMemberPointerType()))) { 5412 ImpCastExprToType(rex, lType, CastExpr::CK_NullToMemberPointer); 5413 return ResultTy; 5414 } 5415 if (LHSIsNull && 5416 (rType->isPointerType() || 5417 (!isRelational && rType->isMemberPointerType()))) { 5418 ImpCastExprToType(lex, rType, CastExpr::CK_NullToMemberPointer); 5419 return ResultTy; 5420 } 5421 5422 // Comparison of member pointers. 5423 if (!isRelational && 5424 lType->isMemberPointerType() && rType->isMemberPointerType()) { 5425 // C++ [expr.eq]p2: 5426 // In addition, pointers to members can be compared, or a pointer to 5427 // member and a null pointer constant. Pointer to member conversions 5428 // (4.11) and qualification conversions (4.4) are performed to bring 5429 // them to a common type. If one operand is a null pointer constant, 5430 // the common type is the type of the other operand. Otherwise, the 5431 // common type is a pointer to member type similar (4.4) to the type 5432 // of one of the operands, with a cv-qualification signature (4.4) 5433 // that is the union of the cv-qualification signatures of the operand 5434 // types. 5435 bool NonStandardCompositeType = false; 5436 QualType T = FindCompositePointerType(Loc, lex, rex, 5437 isSFINAEContext()? 0 : &NonStandardCompositeType); 5438 if (T.isNull()) { 5439 Diag(Loc, diag::err_typecheck_comparison_of_distinct_pointers) 5440 << lType << rType << lex->getSourceRange() << rex->getSourceRange(); 5441 return QualType(); 5442 } else if (NonStandardCompositeType) { 5443 Diag(Loc, 5444 diag::ext_typecheck_comparison_of_distinct_pointers_nonstandard) 5445 << lType << rType << T 5446 << lex->getSourceRange() << rex->getSourceRange(); 5447 } 5448 5449 ImpCastExprToType(lex, T, CastExpr::CK_BitCast); 5450 ImpCastExprToType(rex, T, CastExpr::CK_BitCast); 5451 return ResultTy; 5452 } 5453 5454 // Comparison of nullptr_t with itself. 5455 if (lType->isNullPtrType() && rType->isNullPtrType()) 5456 return ResultTy; 5457 } 5458 5459 // Handle block pointer types. 5460 if (!isRelational && lType->isBlockPointerType() && rType->isBlockPointerType()) { 5461 QualType lpointee = lType->getAs<BlockPointerType>()->getPointeeType(); 5462 QualType rpointee = rType->getAs<BlockPointerType>()->getPointeeType(); 5463 5464 if (!LHSIsNull && !RHSIsNull && 5465 !Context.typesAreCompatible(lpointee, rpointee)) { 5466 Diag(Loc, diag::err_typecheck_comparison_of_distinct_blocks) 5467 << lType << rType << lex->getSourceRange() << rex->getSourceRange(); 5468 } 5469 ImpCastExprToType(rex, lType, CastExpr::CK_BitCast); 5470 return ResultTy; 5471 } 5472 // Allow block pointers to be compared with null pointer constants. 5473 if (!isRelational 5474 && ((lType->isBlockPointerType() && rType->isPointerType()) 5475 || (lType->isPointerType() && rType->isBlockPointerType()))) { 5476 if (!LHSIsNull && !RHSIsNull) { 5477 if (!((rType->isPointerType() && rType->getAs<PointerType>() 5478 ->getPointeeType()->isVoidType()) 5479 || (lType->isPointerType() && lType->getAs<PointerType>() 5480 ->getPointeeType()->isVoidType()))) 5481 Diag(Loc, diag::err_typecheck_comparison_of_distinct_blocks) 5482 << lType << rType << lex->getSourceRange() << rex->getSourceRange(); 5483 } 5484 ImpCastExprToType(rex, lType, CastExpr::CK_BitCast); 5485 return ResultTy; 5486 } 5487 5488 if ((lType->isObjCObjectPointerType() || rType->isObjCObjectPointerType())) { 5489 if (lType->isPointerType() || rType->isPointerType()) { 5490 const PointerType *LPT = lType->getAs<PointerType>(); 5491 const PointerType *RPT = rType->getAs<PointerType>(); 5492 bool LPtrToVoid = LPT ? 5493 Context.getCanonicalType(LPT->getPointeeType())->isVoidType() : false; 5494 bool RPtrToVoid = RPT ? 5495 Context.getCanonicalType(RPT->getPointeeType())->isVoidType() : false; 5496 5497 if (!LPtrToVoid && !RPtrToVoid && 5498 !Context.typesAreCompatible(lType, rType)) { 5499 Diag(Loc, diag::ext_typecheck_comparison_of_distinct_pointers) 5500 << lType << rType << lex->getSourceRange() << rex->getSourceRange(); 5501 } 5502 ImpCastExprToType(rex, lType, CastExpr::CK_BitCast); 5503 return ResultTy; 5504 } 5505 if (lType->isObjCObjectPointerType() && rType->isObjCObjectPointerType()) { 5506 if (!Context.areComparableObjCPointerTypes(lType, rType)) 5507 Diag(Loc, diag::ext_typecheck_comparison_of_distinct_pointers) 5508 << lType << rType << lex->getSourceRange() << rex->getSourceRange(); 5509 ImpCastExprToType(rex, lType, CastExpr::CK_BitCast); 5510 return ResultTy; 5511 } 5512 } 5513 if (lType->isAnyPointerType() && rType->isIntegerType()) { 5514 unsigned DiagID = 0; 5515 if (RHSIsNull) { 5516 if (isRelational) 5517 DiagID = diag::ext_typecheck_ordered_comparison_of_pointer_and_zero; 5518 } else if (isRelational) 5519 DiagID = diag::ext_typecheck_ordered_comparison_of_pointer_integer; 5520 else 5521 DiagID = diag::ext_typecheck_comparison_of_pointer_integer; 5522 5523 if (DiagID) { 5524 Diag(Loc, DiagID) 5525 << lType << rType << lex->getSourceRange() << rex->getSourceRange(); 5526 } 5527 ImpCastExprToType(rex, lType, CastExpr::CK_IntegralToPointer); 5528 return ResultTy; 5529 } 5530 if (lType->isIntegerType() && rType->isAnyPointerType()) { 5531 unsigned DiagID = 0; 5532 if (LHSIsNull) { 5533 if (isRelational) 5534 DiagID = diag::ext_typecheck_ordered_comparison_of_pointer_and_zero; 5535 } else if (isRelational) 5536 DiagID = diag::ext_typecheck_ordered_comparison_of_pointer_integer; 5537 else 5538 DiagID = diag::ext_typecheck_comparison_of_pointer_integer; 5539 5540 if (DiagID) { 5541 Diag(Loc, DiagID) 5542 << lType << rType << lex->getSourceRange() << rex->getSourceRange(); 5543 } 5544 ImpCastExprToType(lex, rType, CastExpr::CK_IntegralToPointer); 5545 return ResultTy; 5546 } 5547 // Handle block pointers. 5548 if (!isRelational && RHSIsNull 5549 && lType->isBlockPointerType() && rType->isIntegerType()) { 5550 ImpCastExprToType(rex, lType, CastExpr::CK_IntegralToPointer); 5551 return ResultTy; 5552 } 5553 if (!isRelational && LHSIsNull 5554 && lType->isIntegerType() && rType->isBlockPointerType()) { 5555 ImpCastExprToType(lex, rType, CastExpr::CK_IntegralToPointer); 5556 return ResultTy; 5557 } 5558 return InvalidOperands(Loc, lex, rex); 5559} 5560 5561/// CheckVectorCompareOperands - vector comparisons are a clang extension that 5562/// operates on extended vector types. Instead of producing an IntTy result, 5563/// like a scalar comparison, a vector comparison produces a vector of integer 5564/// types. 5565QualType Sema::CheckVectorCompareOperands(Expr *&lex, Expr *&rex, 5566 SourceLocation Loc, 5567 bool isRelational) { 5568 // Check to make sure we're operating on vectors of the same type and width, 5569 // Allowing one side to be a scalar of element type. 5570 QualType vType = CheckVectorOperands(Loc, lex, rex); 5571 if (vType.isNull()) 5572 return vType; 5573 5574 QualType lType = lex->getType(); 5575 QualType rType = rex->getType(); 5576 5577 // For non-floating point types, check for self-comparisons of the form 5578 // x == x, x != x, x < x, etc. These always evaluate to a constant, and 5579 // often indicate logic errors in the program. 5580 if (!lType->isFloatingType()) { 5581 if (DeclRefExpr* DRL = dyn_cast<DeclRefExpr>(lex->IgnoreParens())) 5582 if (DeclRefExpr* DRR = dyn_cast<DeclRefExpr>(rex->IgnoreParens())) 5583 if (DRL->getDecl() == DRR->getDecl()) 5584 DiagRuntimeBehavior(Loc, PDiag(diag::warn_selfcomparison)); 5585 } 5586 5587 // Check for comparisons of floating point operands using != and ==. 5588 if (!isRelational && lType->isFloatingType()) { 5589 assert (rType->isFloatingType()); 5590 CheckFloatComparison(Loc,lex,rex); 5591 } 5592 5593 // Return the type for the comparison, which is the same as vector type for 5594 // integer vectors, or an integer type of identical size and number of 5595 // elements for floating point vectors. 5596 if (lType->isIntegerType()) 5597 return lType; 5598 5599 const VectorType *VTy = lType->getAs<VectorType>(); 5600 unsigned TypeSize = Context.getTypeSize(VTy->getElementType()); 5601 if (TypeSize == Context.getTypeSize(Context.IntTy)) 5602 return Context.getExtVectorType(Context.IntTy, VTy->getNumElements()); 5603 if (TypeSize == Context.getTypeSize(Context.LongTy)) 5604 return Context.getExtVectorType(Context.LongTy, VTy->getNumElements()); 5605 5606 assert(TypeSize == Context.getTypeSize(Context.LongLongTy) && 5607 "Unhandled vector element size in vector compare"); 5608 return Context.getExtVectorType(Context.LongLongTy, VTy->getNumElements()); 5609} 5610 5611inline QualType Sema::CheckBitwiseOperands( 5612 Expr *&lex, Expr *&rex, SourceLocation Loc, bool isCompAssign) { 5613 if (lex->getType()->isVectorType() || rex->getType()->isVectorType()) 5614 return CheckVectorOperands(Loc, lex, rex); 5615 5616 QualType compType = UsualArithmeticConversions(lex, rex, isCompAssign); 5617 5618 if (lex->getType()->isIntegerType() && rex->getType()->isIntegerType()) 5619 return compType; 5620 return InvalidOperands(Loc, lex, rex); 5621} 5622 5623inline QualType Sema::CheckLogicalOperands( // C99 6.5.[13,14] 5624 Expr *&lex, Expr *&rex, SourceLocation Loc) { 5625 if (!Context.getLangOptions().CPlusPlus) { 5626 UsualUnaryConversions(lex); 5627 UsualUnaryConversions(rex); 5628 5629 if (!lex->getType()->isScalarType() || !rex->getType()->isScalarType()) 5630 return InvalidOperands(Loc, lex, rex); 5631 5632 return Context.IntTy; 5633 } 5634 5635 // C++ [expr.log.and]p1 5636 // C++ [expr.log.or]p1 5637 // The operands are both implicitly converted to type bool (clause 4). 5638 StandardConversionSequence LHS; 5639 if (!IsStandardConversion(lex, Context.BoolTy, 5640 /*InOverloadResolution=*/false, LHS)) 5641 return InvalidOperands(Loc, lex, rex); 5642 5643 if (PerformImplicitConversion(lex, Context.BoolTy, LHS, 5644 AA_Passing, /*IgnoreBaseAccess=*/false)) 5645 return InvalidOperands(Loc, lex, rex); 5646 5647 StandardConversionSequence RHS; 5648 if (!IsStandardConversion(rex, Context.BoolTy, 5649 /*InOverloadResolution=*/false, RHS)) 5650 return InvalidOperands(Loc, lex, rex); 5651 5652 if (PerformImplicitConversion(rex, Context.BoolTy, RHS, 5653 AA_Passing, /*IgnoreBaseAccess=*/false)) 5654 return InvalidOperands(Loc, lex, rex); 5655 5656 // C++ [expr.log.and]p2 5657 // C++ [expr.log.or]p2 5658 // The result is a bool. 5659 return Context.BoolTy; 5660} 5661 5662/// IsReadonlyProperty - Verify that otherwise a valid l-value expression 5663/// is a read-only property; return true if so. A readonly property expression 5664/// depends on various declarations and thus must be treated specially. 5665/// 5666static bool IsReadonlyProperty(Expr *E, Sema &S) { 5667 if (E->getStmtClass() == Expr::ObjCPropertyRefExprClass) { 5668 const ObjCPropertyRefExpr* PropExpr = cast<ObjCPropertyRefExpr>(E); 5669 if (ObjCPropertyDecl *PDecl = PropExpr->getProperty()) { 5670 QualType BaseType = PropExpr->getBase()->getType(); 5671 if (const ObjCObjectPointerType *OPT = 5672 BaseType->getAsObjCInterfacePointerType()) 5673 if (ObjCInterfaceDecl *IFace = OPT->getInterfaceDecl()) 5674 if (S.isPropertyReadonly(PDecl, IFace)) 5675 return true; 5676 } 5677 } 5678 return false; 5679} 5680 5681/// CheckForModifiableLvalue - Verify that E is a modifiable lvalue. If not, 5682/// emit an error and return true. If so, return false. 5683static bool CheckForModifiableLvalue(Expr *E, SourceLocation Loc, Sema &S) { 5684 SourceLocation OrigLoc = Loc; 5685 Expr::isModifiableLvalueResult IsLV = E->isModifiableLvalue(S.Context, 5686 &Loc); 5687 if (IsLV == Expr::MLV_Valid && IsReadonlyProperty(E, S)) 5688 IsLV = Expr::MLV_ReadonlyProperty; 5689 if (IsLV == Expr::MLV_Valid) 5690 return false; 5691 5692 unsigned Diag = 0; 5693 bool NeedType = false; 5694 switch (IsLV) { // C99 6.5.16p2 5695 case Expr::MLV_ConstQualified: Diag = diag::err_typecheck_assign_const; break; 5696 case Expr::MLV_ArrayType: 5697 Diag = diag::err_typecheck_array_not_modifiable_lvalue; 5698 NeedType = true; 5699 break; 5700 case Expr::MLV_NotObjectType: 5701 Diag = diag::err_typecheck_non_object_not_modifiable_lvalue; 5702 NeedType = true; 5703 break; 5704 case Expr::MLV_LValueCast: 5705 Diag = diag::err_typecheck_lvalue_casts_not_supported; 5706 break; 5707 case Expr::MLV_Valid: 5708 llvm_unreachable("did not take early return for MLV_Valid"); 5709 case Expr::MLV_InvalidExpression: 5710 case Expr::MLV_MemberFunction: 5711 case Expr::MLV_ClassTemporary: 5712 Diag = diag::err_typecheck_expression_not_modifiable_lvalue; 5713 break; 5714 case Expr::MLV_IncompleteType: 5715 case Expr::MLV_IncompleteVoidType: 5716 return S.RequireCompleteType(Loc, E->getType(), 5717 S.PDiag(diag::err_typecheck_incomplete_type_not_modifiable_lvalue) 5718 << E->getSourceRange()); 5719 case Expr::MLV_DuplicateVectorComponents: 5720 Diag = diag::err_typecheck_duplicate_vector_components_not_mlvalue; 5721 break; 5722 case Expr::MLV_NotBlockQualified: 5723 Diag = diag::err_block_decl_ref_not_modifiable_lvalue; 5724 break; 5725 case Expr::MLV_ReadonlyProperty: 5726 Diag = diag::error_readonly_property_assignment; 5727 break; 5728 case Expr::MLV_NoSetterProperty: 5729 Diag = diag::error_nosetter_property_assignment; 5730 break; 5731 case Expr::MLV_SubObjCPropertySetting: 5732 Diag = diag::error_no_subobject_property_setting; 5733 break; 5734 } 5735 5736 SourceRange Assign; 5737 if (Loc != OrigLoc) 5738 Assign = SourceRange(OrigLoc, OrigLoc); 5739 if (NeedType) 5740 S.Diag(Loc, Diag) << E->getType() << E->getSourceRange() << Assign; 5741 else 5742 S.Diag(Loc, Diag) << E->getSourceRange() << Assign; 5743 return true; 5744} 5745 5746 5747 5748// C99 6.5.16.1 5749QualType Sema::CheckAssignmentOperands(Expr *LHS, Expr *&RHS, 5750 SourceLocation Loc, 5751 QualType CompoundType) { 5752 // Verify that LHS is a modifiable lvalue, and emit error if not. 5753 if (CheckForModifiableLvalue(LHS, Loc, *this)) 5754 return QualType(); 5755 5756 QualType LHSType = LHS->getType(); 5757 QualType RHSType = CompoundType.isNull() ? RHS->getType() : CompoundType; 5758 5759 AssignConvertType ConvTy; 5760 if (CompoundType.isNull()) { 5761 // Simple assignment "x = y". 5762 ConvTy = CheckSingleAssignmentConstraints(LHSType, RHS); 5763 // Special case of NSObject attributes on c-style pointer types. 5764 if (ConvTy == IncompatiblePointer && 5765 ((Context.isObjCNSObjectType(LHSType) && 5766 RHSType->isObjCObjectPointerType()) || 5767 (Context.isObjCNSObjectType(RHSType) && 5768 LHSType->isObjCObjectPointerType()))) 5769 ConvTy = Compatible; 5770 5771 // If the RHS is a unary plus or minus, check to see if they = and + are 5772 // right next to each other. If so, the user may have typo'd "x =+ 4" 5773 // instead of "x += 4". 5774 Expr *RHSCheck = RHS; 5775 if (ImplicitCastExpr *ICE = dyn_cast<ImplicitCastExpr>(RHSCheck)) 5776 RHSCheck = ICE->getSubExpr(); 5777 if (UnaryOperator *UO = dyn_cast<UnaryOperator>(RHSCheck)) { 5778 if ((UO->getOpcode() == UnaryOperator::Plus || 5779 UO->getOpcode() == UnaryOperator::Minus) && 5780 Loc.isFileID() && UO->getOperatorLoc().isFileID() && 5781 // Only if the two operators are exactly adjacent. 5782 Loc.getFileLocWithOffset(1) == UO->getOperatorLoc() && 5783 // And there is a space or other character before the subexpr of the 5784 // unary +/-. We don't want to warn on "x=-1". 5785 Loc.getFileLocWithOffset(2) != UO->getSubExpr()->getLocStart() && 5786 UO->getSubExpr()->getLocStart().isFileID()) { 5787 Diag(Loc, diag::warn_not_compound_assign) 5788 << (UO->getOpcode() == UnaryOperator::Plus ? "+" : "-") 5789 << SourceRange(UO->getOperatorLoc(), UO->getOperatorLoc()); 5790 } 5791 } 5792 } else { 5793 // Compound assignment "x += y" 5794 ConvTy = CheckAssignmentConstraints(LHSType, RHSType); 5795 } 5796 5797 if (DiagnoseAssignmentResult(ConvTy, Loc, LHSType, RHSType, 5798 RHS, AA_Assigning)) 5799 return QualType(); 5800 5801 // C99 6.5.16p3: The type of an assignment expression is the type of the 5802 // left operand unless the left operand has qualified type, in which case 5803 // it is the unqualified version of the type of the left operand. 5804 // C99 6.5.16.1p2: In simple assignment, the value of the right operand 5805 // is converted to the type of the assignment expression (above). 5806 // C++ 5.17p1: the type of the assignment expression is that of its left 5807 // operand. 5808 return LHSType.getUnqualifiedType(); 5809} 5810 5811// C99 6.5.17 5812QualType Sema::CheckCommaOperands(Expr *LHS, Expr *&RHS, SourceLocation Loc) { 5813 // Comma performs lvalue conversion (C99 6.3.2.1), but not unary conversions. 5814 // C++ does not perform this conversion (C++ [expr.comma]p1). 5815 if (!getLangOptions().CPlusPlus) 5816 DefaultFunctionArrayLvalueConversion(RHS); 5817 5818 // FIXME: Check that RHS type is complete in C mode (it's legal for it to be 5819 // incomplete in C++). 5820 5821 return RHS->getType(); 5822} 5823 5824/// CheckIncrementDecrementOperand - unlike most "Check" methods, this routine 5825/// doesn't need to call UsualUnaryConversions or UsualArithmeticConversions. 5826QualType Sema::CheckIncrementDecrementOperand(Expr *Op, SourceLocation OpLoc, 5827 bool isInc) { 5828 if (Op->isTypeDependent()) 5829 return Context.DependentTy; 5830 5831 QualType ResType = Op->getType(); 5832 assert(!ResType.isNull() && "no type for increment/decrement expression"); 5833 5834 if (getLangOptions().CPlusPlus && ResType->isBooleanType()) { 5835 // Decrement of bool is not allowed. 5836 if (!isInc) { 5837 Diag(OpLoc, diag::err_decrement_bool) << Op->getSourceRange(); 5838 return QualType(); 5839 } 5840 // Increment of bool sets it to true, but is deprecated. 5841 Diag(OpLoc, diag::warn_increment_bool) << Op->getSourceRange(); 5842 } else if (ResType->isRealType()) { 5843 // OK! 5844 } else if (ResType->isAnyPointerType()) { 5845 QualType PointeeTy = ResType->getPointeeType(); 5846 5847 // C99 6.5.2.4p2, 6.5.6p2 5848 if (PointeeTy->isVoidType()) { 5849 if (getLangOptions().CPlusPlus) { 5850 Diag(OpLoc, diag::err_typecheck_pointer_arith_void_type) 5851 << Op->getSourceRange(); 5852 return QualType(); 5853 } 5854 5855 // Pointer to void is a GNU extension in C. 5856 Diag(OpLoc, diag::ext_gnu_void_ptr) << Op->getSourceRange(); 5857 } else if (PointeeTy->isFunctionType()) { 5858 if (getLangOptions().CPlusPlus) { 5859 Diag(OpLoc, diag::err_typecheck_pointer_arith_function_type) 5860 << Op->getType() << Op->getSourceRange(); 5861 return QualType(); 5862 } 5863 5864 Diag(OpLoc, diag::ext_gnu_ptr_func_arith) 5865 << ResType << Op->getSourceRange(); 5866 } else if (RequireCompleteType(OpLoc, PointeeTy, 5867 PDiag(diag::err_typecheck_arithmetic_incomplete_type) 5868 << Op->getSourceRange() 5869 << ResType)) 5870 return QualType(); 5871 // Diagnose bad cases where we step over interface counts. 5872 else if (PointeeTy->isObjCInterfaceType() && LangOpts.ObjCNonFragileABI) { 5873 Diag(OpLoc, diag::err_arithmetic_nonfragile_interface) 5874 << PointeeTy << Op->getSourceRange(); 5875 return QualType(); 5876 } 5877 } else if (ResType->isAnyComplexType()) { 5878 // C99 does not support ++/-- on complex types, we allow as an extension. 5879 Diag(OpLoc, diag::ext_integer_increment_complex) 5880 << ResType << Op->getSourceRange(); 5881 } else { 5882 Diag(OpLoc, diag::err_typecheck_illegal_increment_decrement) 5883 << ResType << int(isInc) << Op->getSourceRange(); 5884 return QualType(); 5885 } 5886 // At this point, we know we have a real, complex or pointer type. 5887 // Now make sure the operand is a modifiable lvalue. 5888 if (CheckForModifiableLvalue(Op, OpLoc, *this)) 5889 return QualType(); 5890 return ResType; 5891} 5892 5893/// getPrimaryDecl - Helper function for CheckAddressOfOperand(). 5894/// This routine allows us to typecheck complex/recursive expressions 5895/// where the declaration is needed for type checking. We only need to 5896/// handle cases when the expression references a function designator 5897/// or is an lvalue. Here are some examples: 5898/// - &(x) => x 5899/// - &*****f => f for f a function designator. 5900/// - &s.xx => s 5901/// - &s.zz[1].yy -> s, if zz is an array 5902/// - *(x + 1) -> x, if x is an array 5903/// - &"123"[2] -> 0 5904/// - & __real__ x -> x 5905static NamedDecl *getPrimaryDecl(Expr *E) { 5906 switch (E->getStmtClass()) { 5907 case Stmt::DeclRefExprClass: 5908 return cast<DeclRefExpr>(E)->getDecl(); 5909 case Stmt::MemberExprClass: 5910 // If this is an arrow operator, the address is an offset from 5911 // the base's value, so the object the base refers to is 5912 // irrelevant. 5913 if (cast<MemberExpr>(E)->isArrow()) 5914 return 0; 5915 // Otherwise, the expression refers to a part of the base 5916 return getPrimaryDecl(cast<MemberExpr>(E)->getBase()); 5917 case Stmt::ArraySubscriptExprClass: { 5918 // FIXME: This code shouldn't be necessary! We should catch the implicit 5919 // promotion of register arrays earlier. 5920 Expr* Base = cast<ArraySubscriptExpr>(E)->getBase(); 5921 if (ImplicitCastExpr* ICE = dyn_cast<ImplicitCastExpr>(Base)) { 5922 if (ICE->getSubExpr()->getType()->isArrayType()) 5923 return getPrimaryDecl(ICE->getSubExpr()); 5924 } 5925 return 0; 5926 } 5927 case Stmt::UnaryOperatorClass: { 5928 UnaryOperator *UO = cast<UnaryOperator>(E); 5929 5930 switch(UO->getOpcode()) { 5931 case UnaryOperator::Real: 5932 case UnaryOperator::Imag: 5933 case UnaryOperator::Extension: 5934 return getPrimaryDecl(UO->getSubExpr()); 5935 default: 5936 return 0; 5937 } 5938 } 5939 case Stmt::ParenExprClass: 5940 return getPrimaryDecl(cast<ParenExpr>(E)->getSubExpr()); 5941 case Stmt::ImplicitCastExprClass: 5942 // If the result of an implicit cast is an l-value, we care about 5943 // the sub-expression; otherwise, the result here doesn't matter. 5944 return getPrimaryDecl(cast<ImplicitCastExpr>(E)->getSubExpr()); 5945 default: 5946 return 0; 5947 } 5948} 5949 5950/// CheckAddressOfOperand - The operand of & must be either a function 5951/// designator or an lvalue designating an object. If it is an lvalue, the 5952/// object cannot be declared with storage class register or be a bit field. 5953/// Note: The usual conversions are *not* applied to the operand of the & 5954/// operator (C99 6.3.2.1p[2-4]), and its result is never an lvalue. 5955/// In C++, the operand might be an overloaded function name, in which case 5956/// we allow the '&' but retain the overloaded-function type. 5957QualType Sema::CheckAddressOfOperand(Expr *op, SourceLocation OpLoc) { 5958 // Make sure to ignore parentheses in subsequent checks 5959 op = op->IgnoreParens(); 5960 5961 if (op->isTypeDependent()) 5962 return Context.DependentTy; 5963 5964 if (getLangOptions().C99) { 5965 // Implement C99-only parts of addressof rules. 5966 if (UnaryOperator* uOp = dyn_cast<UnaryOperator>(op)) { 5967 if (uOp->getOpcode() == UnaryOperator::Deref) 5968 // Per C99 6.5.3.2, the address of a deref always returns a valid result 5969 // (assuming the deref expression is valid). 5970 return uOp->getSubExpr()->getType(); 5971 } 5972 // Technically, there should be a check for array subscript 5973 // expressions here, but the result of one is always an lvalue anyway. 5974 } 5975 NamedDecl *dcl = getPrimaryDecl(op); 5976 Expr::isLvalueResult lval = op->isLvalue(Context); 5977 5978 MemberExpr *ME = dyn_cast<MemberExpr>(op); 5979 if (lval == Expr::LV_MemberFunction && ME && 5980 isa<CXXMethodDecl>(ME->getMemberDecl())) { 5981 ValueDecl *dcl = cast<MemberExpr>(op)->getMemberDecl(); 5982 // &f where f is a member of the current object, or &o.f, or &p->f 5983 // All these are not allowed, and we need to catch them before the dcl 5984 // branch of the if, below. 5985 Diag(OpLoc, diag::err_unqualified_pointer_member_function) 5986 << dcl; 5987 // FIXME: Improve this diagnostic and provide a fixit. 5988 5989 // Now recover by acting as if the function had been accessed qualified. 5990 return Context.getMemberPointerType(op->getType(), 5991 Context.getTypeDeclType(cast<RecordDecl>(dcl->getDeclContext())) 5992 .getTypePtr()); 5993 } else if (lval == Expr::LV_ClassTemporary) { 5994 Diag(OpLoc, isSFINAEContext()? diag::err_typecheck_addrof_class_temporary 5995 : diag::ext_typecheck_addrof_class_temporary) 5996 << op->getType() << op->getSourceRange(); 5997 if (isSFINAEContext()) 5998 return QualType(); 5999 } else if (lval != Expr::LV_Valid && lval != Expr::LV_IncompleteVoidType) { 6000 // C99 6.5.3.2p1 6001 // The operand must be either an l-value or a function designator 6002 if (!op->getType()->isFunctionType()) { 6003 // FIXME: emit more specific diag... 6004 Diag(OpLoc, diag::err_typecheck_invalid_lvalue_addrof) 6005 << op->getSourceRange(); 6006 return QualType(); 6007 } 6008 } else if (op->getBitField()) { // C99 6.5.3.2p1 6009 // The operand cannot be a bit-field 6010 Diag(OpLoc, diag::err_typecheck_address_of) 6011 << "bit-field" << op->getSourceRange(); 6012 return QualType(); 6013 } else if (op->refersToVectorElement()) { 6014 // The operand cannot be an element of a vector 6015 Diag(OpLoc, diag::err_typecheck_address_of) 6016 << "vector element" << op->getSourceRange(); 6017 return QualType(); 6018 } else if (isa<ObjCPropertyRefExpr>(op)) { 6019 // cannot take address of a property expression. 6020 Diag(OpLoc, diag::err_typecheck_address_of) 6021 << "property expression" << op->getSourceRange(); 6022 return QualType(); 6023 } else if (ConditionalOperator *CO = dyn_cast<ConditionalOperator>(op)) { 6024 // FIXME: Can LHS ever be null here? 6025 if (!CheckAddressOfOperand(CO->getTrueExpr(), OpLoc).isNull()) 6026 return CheckAddressOfOperand(CO->getFalseExpr(), OpLoc); 6027 } else if (isa<UnresolvedLookupExpr>(op)) { 6028 return Context.OverloadTy; 6029 } else if (dcl) { // C99 6.5.3.2p1 6030 // We have an lvalue with a decl. Make sure the decl is not declared 6031 // with the register storage-class specifier. 6032 if (const VarDecl *vd = dyn_cast<VarDecl>(dcl)) { 6033 if (vd->getStorageClass() == VarDecl::Register) { 6034 Diag(OpLoc, diag::err_typecheck_address_of) 6035 << "register variable" << op->getSourceRange(); 6036 return QualType(); 6037 } 6038 } else if (isa<FunctionTemplateDecl>(dcl)) { 6039 return Context.OverloadTy; 6040 } else if (FieldDecl *FD = dyn_cast<FieldDecl>(dcl)) { 6041 // Okay: we can take the address of a field. 6042 // Could be a pointer to member, though, if there is an explicit 6043 // scope qualifier for the class. 6044 if (isa<DeclRefExpr>(op) && cast<DeclRefExpr>(op)->getQualifier()) { 6045 DeclContext *Ctx = dcl->getDeclContext(); 6046 if (Ctx && Ctx->isRecord()) { 6047 if (FD->getType()->isReferenceType()) { 6048 Diag(OpLoc, 6049 diag::err_cannot_form_pointer_to_member_of_reference_type) 6050 << FD->getDeclName() << FD->getType(); 6051 return QualType(); 6052 } 6053 6054 return Context.getMemberPointerType(op->getType(), 6055 Context.getTypeDeclType(cast<RecordDecl>(Ctx)).getTypePtr()); 6056 } 6057 } 6058 } else if (CXXMethodDecl *MD = dyn_cast<CXXMethodDecl>(dcl)) { 6059 // Okay: we can take the address of a function. 6060 // As above. 6061 if (isa<DeclRefExpr>(op) && cast<DeclRefExpr>(op)->getQualifier() && 6062 MD->isInstance()) 6063 return Context.getMemberPointerType(op->getType(), 6064 Context.getTypeDeclType(MD->getParent()).getTypePtr()); 6065 } else if (!isa<FunctionDecl>(dcl)) 6066 assert(0 && "Unknown/unexpected decl type"); 6067 } 6068 6069 if (lval == Expr::LV_IncompleteVoidType) { 6070 // Taking the address of a void variable is technically illegal, but we 6071 // allow it in cases which are otherwise valid. 6072 // Example: "extern void x; void* y = &x;". 6073 Diag(OpLoc, diag::ext_typecheck_addrof_void) << op->getSourceRange(); 6074 } 6075 6076 // If the operand has type "type", the result has type "pointer to type". 6077 return Context.getPointerType(op->getType()); 6078} 6079 6080QualType Sema::CheckIndirectionOperand(Expr *Op, SourceLocation OpLoc) { 6081 if (Op->isTypeDependent()) 6082 return Context.DependentTy; 6083 6084 UsualUnaryConversions(Op); 6085 QualType Ty = Op->getType(); 6086 6087 // Note that per both C89 and C99, this is always legal, even if ptype is an 6088 // incomplete type or void. It would be possible to warn about dereferencing 6089 // a void pointer, but it's completely well-defined, and such a warning is 6090 // unlikely to catch any mistakes. 6091 if (const PointerType *PT = Ty->getAs<PointerType>()) 6092 return PT->getPointeeType(); 6093 6094 if (const ObjCObjectPointerType *OPT = Ty->getAs<ObjCObjectPointerType>()) 6095 return OPT->getPointeeType(); 6096 6097 Diag(OpLoc, diag::err_typecheck_indirection_requires_pointer) 6098 << Ty << Op->getSourceRange(); 6099 return QualType(); 6100} 6101 6102static inline BinaryOperator::Opcode ConvertTokenKindToBinaryOpcode( 6103 tok::TokenKind Kind) { 6104 BinaryOperator::Opcode Opc; 6105 switch (Kind) { 6106 default: assert(0 && "Unknown binop!"); 6107 case tok::periodstar: Opc = BinaryOperator::PtrMemD; break; 6108 case tok::arrowstar: Opc = BinaryOperator::PtrMemI; break; 6109 case tok::star: Opc = BinaryOperator::Mul; break; 6110 case tok::slash: Opc = BinaryOperator::Div; break; 6111 case tok::percent: Opc = BinaryOperator::Rem; break; 6112 case tok::plus: Opc = BinaryOperator::Add; break; 6113 case tok::minus: Opc = BinaryOperator::Sub; break; 6114 case tok::lessless: Opc = BinaryOperator::Shl; break; 6115 case tok::greatergreater: Opc = BinaryOperator::Shr; break; 6116 case tok::lessequal: Opc = BinaryOperator::LE; break; 6117 case tok::less: Opc = BinaryOperator::LT; break; 6118 case tok::greaterequal: Opc = BinaryOperator::GE; break; 6119 case tok::greater: Opc = BinaryOperator::GT; break; 6120 case tok::exclaimequal: Opc = BinaryOperator::NE; break; 6121 case tok::equalequal: Opc = BinaryOperator::EQ; break; 6122 case tok::amp: Opc = BinaryOperator::And; break; 6123 case tok::caret: Opc = BinaryOperator::Xor; break; 6124 case tok::pipe: Opc = BinaryOperator::Or; break; 6125 case tok::ampamp: Opc = BinaryOperator::LAnd; break; 6126 case tok::pipepipe: Opc = BinaryOperator::LOr; break; 6127 case tok::equal: Opc = BinaryOperator::Assign; break; 6128 case tok::starequal: Opc = BinaryOperator::MulAssign; break; 6129 case tok::slashequal: Opc = BinaryOperator::DivAssign; break; 6130 case tok::percentequal: Opc = BinaryOperator::RemAssign; break; 6131 case tok::plusequal: Opc = BinaryOperator::AddAssign; break; 6132 case tok::minusequal: Opc = BinaryOperator::SubAssign; break; 6133 case tok::lesslessequal: Opc = BinaryOperator::ShlAssign; break; 6134 case tok::greatergreaterequal: Opc = BinaryOperator::ShrAssign; break; 6135 case tok::ampequal: Opc = BinaryOperator::AndAssign; break; 6136 case tok::caretequal: Opc = BinaryOperator::XorAssign; break; 6137 case tok::pipeequal: Opc = BinaryOperator::OrAssign; break; 6138 case tok::comma: Opc = BinaryOperator::Comma; break; 6139 } 6140 return Opc; 6141} 6142 6143static inline UnaryOperator::Opcode ConvertTokenKindToUnaryOpcode( 6144 tok::TokenKind Kind) { 6145 UnaryOperator::Opcode Opc; 6146 switch (Kind) { 6147 default: assert(0 && "Unknown unary op!"); 6148 case tok::plusplus: Opc = UnaryOperator::PreInc; break; 6149 case tok::minusminus: Opc = UnaryOperator::PreDec; break; 6150 case tok::amp: Opc = UnaryOperator::AddrOf; break; 6151 case tok::star: Opc = UnaryOperator::Deref; break; 6152 case tok::plus: Opc = UnaryOperator::Plus; break; 6153 case tok::minus: Opc = UnaryOperator::Minus; break; 6154 case tok::tilde: Opc = UnaryOperator::Not; break; 6155 case tok::exclaim: Opc = UnaryOperator::LNot; break; 6156 case tok::kw___real: Opc = UnaryOperator::Real; break; 6157 case tok::kw___imag: Opc = UnaryOperator::Imag; break; 6158 case tok::kw___extension__: Opc = UnaryOperator::Extension; break; 6159 } 6160 return Opc; 6161} 6162 6163/// CreateBuiltinBinOp - Creates a new built-in binary operation with 6164/// operator @p Opc at location @c TokLoc. This routine only supports 6165/// built-in operations; ActOnBinOp handles overloaded operators. 6166Action::OwningExprResult Sema::CreateBuiltinBinOp(SourceLocation OpLoc, 6167 unsigned Op, 6168 Expr *lhs, Expr *rhs) { 6169 QualType ResultTy; // Result type of the binary operator. 6170 BinaryOperator::Opcode Opc = (BinaryOperator::Opcode)Op; 6171 // The following two variables are used for compound assignment operators 6172 QualType CompLHSTy; // Type of LHS after promotions for computation 6173 QualType CompResultTy; // Type of computation result 6174 6175 switch (Opc) { 6176 case BinaryOperator::Assign: 6177 ResultTy = CheckAssignmentOperands(lhs, rhs, OpLoc, QualType()); 6178 break; 6179 case BinaryOperator::PtrMemD: 6180 case BinaryOperator::PtrMemI: 6181 ResultTy = CheckPointerToMemberOperands(lhs, rhs, OpLoc, 6182 Opc == BinaryOperator::PtrMemI); 6183 break; 6184 case BinaryOperator::Mul: 6185 case BinaryOperator::Div: 6186 ResultTy = CheckMultiplyDivideOperands(lhs, rhs, OpLoc, false, 6187 Opc == BinaryOperator::Div); 6188 break; 6189 case BinaryOperator::Rem: 6190 ResultTy = CheckRemainderOperands(lhs, rhs, OpLoc); 6191 break; 6192 case BinaryOperator::Add: 6193 ResultTy = CheckAdditionOperands(lhs, rhs, OpLoc); 6194 break; 6195 case BinaryOperator::Sub: 6196 ResultTy = CheckSubtractionOperands(lhs, rhs, OpLoc); 6197 break; 6198 case BinaryOperator::Shl: 6199 case BinaryOperator::Shr: 6200 ResultTy = CheckShiftOperands(lhs, rhs, OpLoc); 6201 break; 6202 case BinaryOperator::LE: 6203 case BinaryOperator::LT: 6204 case BinaryOperator::GE: 6205 case BinaryOperator::GT: 6206 ResultTy = CheckCompareOperands(lhs, rhs, OpLoc, Opc, true); 6207 break; 6208 case BinaryOperator::EQ: 6209 case BinaryOperator::NE: 6210 ResultTy = CheckCompareOperands(lhs, rhs, OpLoc, Opc, false); 6211 break; 6212 case BinaryOperator::And: 6213 case BinaryOperator::Xor: 6214 case BinaryOperator::Or: 6215 ResultTy = CheckBitwiseOperands(lhs, rhs, OpLoc); 6216 break; 6217 case BinaryOperator::LAnd: 6218 case BinaryOperator::LOr: 6219 ResultTy = CheckLogicalOperands(lhs, rhs, OpLoc); 6220 break; 6221 case BinaryOperator::MulAssign: 6222 case BinaryOperator::DivAssign: 6223 CompResultTy = CheckMultiplyDivideOperands(lhs, rhs, OpLoc, true, 6224 Opc == BinaryOperator::DivAssign); 6225 CompLHSTy = CompResultTy; 6226 if (!CompResultTy.isNull()) 6227 ResultTy = CheckAssignmentOperands(lhs, rhs, OpLoc, CompResultTy); 6228 break; 6229 case BinaryOperator::RemAssign: 6230 CompResultTy = CheckRemainderOperands(lhs, rhs, OpLoc, true); 6231 CompLHSTy = CompResultTy; 6232 if (!CompResultTy.isNull()) 6233 ResultTy = CheckAssignmentOperands(lhs, rhs, OpLoc, CompResultTy); 6234 break; 6235 case BinaryOperator::AddAssign: 6236 CompResultTy = CheckAdditionOperands(lhs, rhs, OpLoc, &CompLHSTy); 6237 if (!CompResultTy.isNull()) 6238 ResultTy = CheckAssignmentOperands(lhs, rhs, OpLoc, CompResultTy); 6239 break; 6240 case BinaryOperator::SubAssign: 6241 CompResultTy = CheckSubtractionOperands(lhs, rhs, OpLoc, &CompLHSTy); 6242 if (!CompResultTy.isNull()) 6243 ResultTy = CheckAssignmentOperands(lhs, rhs, OpLoc, CompResultTy); 6244 break; 6245 case BinaryOperator::ShlAssign: 6246 case BinaryOperator::ShrAssign: 6247 CompResultTy = CheckShiftOperands(lhs, rhs, OpLoc, true); 6248 CompLHSTy = CompResultTy; 6249 if (!CompResultTy.isNull()) 6250 ResultTy = CheckAssignmentOperands(lhs, rhs, OpLoc, CompResultTy); 6251 break; 6252 case BinaryOperator::AndAssign: 6253 case BinaryOperator::XorAssign: 6254 case BinaryOperator::OrAssign: 6255 CompResultTy = CheckBitwiseOperands(lhs, rhs, OpLoc, true); 6256 CompLHSTy = CompResultTy; 6257 if (!CompResultTy.isNull()) 6258 ResultTy = CheckAssignmentOperands(lhs, rhs, OpLoc, CompResultTy); 6259 break; 6260 case BinaryOperator::Comma: 6261 ResultTy = CheckCommaOperands(lhs, rhs, OpLoc); 6262 break; 6263 } 6264 if (ResultTy.isNull()) 6265 return ExprError(); 6266 if (CompResultTy.isNull()) 6267 return Owned(new (Context) BinaryOperator(lhs, rhs, Opc, ResultTy, OpLoc)); 6268 else 6269 return Owned(new (Context) CompoundAssignOperator(lhs, rhs, Opc, ResultTy, 6270 CompLHSTy, CompResultTy, 6271 OpLoc)); 6272} 6273 6274/// SuggestParentheses - Emit a diagnostic together with a fixit hint that wraps 6275/// ParenRange in parentheses. 6276static void SuggestParentheses(Sema &Self, SourceLocation Loc, 6277 const PartialDiagnostic &PD, 6278 const PartialDiagnostic &FirstNote, 6279 SourceRange FirstParenRange, 6280 const PartialDiagnostic &SecondNote, 6281 SourceRange SecondParenRange) { 6282 Self.Diag(Loc, PD); 6283 6284 if (!FirstNote.getDiagID()) 6285 return; 6286 6287 SourceLocation EndLoc = Self.PP.getLocForEndOfToken(FirstParenRange.getEnd()); 6288 if (!FirstParenRange.getEnd().isFileID() || EndLoc.isInvalid()) { 6289 // We can't display the parentheses, so just return. 6290 return; 6291 } 6292 6293 Self.Diag(Loc, FirstNote) 6294 << FixItHint::CreateInsertion(FirstParenRange.getBegin(), "(") 6295 << FixItHint::CreateInsertion(EndLoc, ")"); 6296 6297 if (!SecondNote.getDiagID()) 6298 return; 6299 6300 EndLoc = Self.PP.getLocForEndOfToken(SecondParenRange.getEnd()); 6301 if (!SecondParenRange.getEnd().isFileID() || EndLoc.isInvalid()) { 6302 // We can't display the parentheses, so just dig the 6303 // warning/error and return. 6304 Self.Diag(Loc, SecondNote); 6305 return; 6306 } 6307 6308 Self.Diag(Loc, SecondNote) 6309 << FixItHint::CreateInsertion(SecondParenRange.getBegin(), "(") 6310 << FixItHint::CreateInsertion(EndLoc, ")"); 6311} 6312 6313/// DiagnoseBitwisePrecedence - Emit a warning when bitwise and comparison 6314/// operators are mixed in a way that suggests that the programmer forgot that 6315/// comparison operators have higher precedence. The most typical example of 6316/// such code is "flags & 0x0020 != 0", which is equivalent to "flags & 1". 6317static void DiagnoseBitwisePrecedence(Sema &Self, BinaryOperator::Opcode Opc, 6318 SourceLocation OpLoc,Expr *lhs,Expr *rhs){ 6319 typedef BinaryOperator BinOp; 6320 BinOp::Opcode lhsopc = static_cast<BinOp::Opcode>(-1), 6321 rhsopc = static_cast<BinOp::Opcode>(-1); 6322 if (BinOp *BO = dyn_cast<BinOp>(lhs)) 6323 lhsopc = BO->getOpcode(); 6324 if (BinOp *BO = dyn_cast<BinOp>(rhs)) 6325 rhsopc = BO->getOpcode(); 6326 6327 // Subs are not binary operators. 6328 if (lhsopc == -1 && rhsopc == -1) 6329 return; 6330 6331 // Bitwise operations are sometimes used as eager logical ops. 6332 // Don't diagnose this. 6333 if ((BinOp::isComparisonOp(lhsopc) || BinOp::isBitwiseOp(lhsopc)) && 6334 (BinOp::isComparisonOp(rhsopc) || BinOp::isBitwiseOp(rhsopc))) 6335 return; 6336 6337 if (BinOp::isComparisonOp(lhsopc)) 6338 SuggestParentheses(Self, OpLoc, 6339 Self.PDiag(diag::warn_precedence_bitwise_rel) 6340 << SourceRange(lhs->getLocStart(), OpLoc) 6341 << BinOp::getOpcodeStr(Opc) << BinOp::getOpcodeStr(lhsopc), 6342 Self.PDiag(diag::note_precedence_bitwise_first) 6343 << BinOp::getOpcodeStr(Opc), 6344 SourceRange(cast<BinOp>(lhs)->getRHS()->getLocStart(), rhs->getLocEnd()), 6345 Self.PDiag(diag::note_precedence_bitwise_silence) 6346 << BinOp::getOpcodeStr(lhsopc), 6347 lhs->getSourceRange()); 6348 else if (BinOp::isComparisonOp(rhsopc)) 6349 SuggestParentheses(Self, OpLoc, 6350 Self.PDiag(diag::warn_precedence_bitwise_rel) 6351 << SourceRange(OpLoc, rhs->getLocEnd()) 6352 << BinOp::getOpcodeStr(Opc) << BinOp::getOpcodeStr(rhsopc), 6353 Self.PDiag(diag::note_precedence_bitwise_first) 6354 << BinOp::getOpcodeStr(Opc), 6355 SourceRange(lhs->getLocEnd(), cast<BinOp>(rhs)->getLHS()->getLocStart()), 6356 Self.PDiag(diag::note_precedence_bitwise_silence) 6357 << BinOp::getOpcodeStr(rhsopc), 6358 rhs->getSourceRange()); 6359} 6360 6361/// DiagnoseBinOpPrecedence - Emit warnings for expressions with tricky 6362/// precedence. This currently diagnoses only "arg1 'bitwise' arg2 'eq' arg3". 6363/// But it could also warn about arg1 && arg2 || arg3, as GCC 4.3+ does. 6364static void DiagnoseBinOpPrecedence(Sema &Self, BinaryOperator::Opcode Opc, 6365 SourceLocation OpLoc, Expr *lhs, Expr *rhs){ 6366 if (BinaryOperator::isBitwiseOp(Opc)) 6367 DiagnoseBitwisePrecedence(Self, Opc, OpLoc, lhs, rhs); 6368} 6369 6370// Binary Operators. 'Tok' is the token for the operator. 6371Action::OwningExprResult Sema::ActOnBinOp(Scope *S, SourceLocation TokLoc, 6372 tok::TokenKind Kind, 6373 ExprArg LHS, ExprArg RHS) { 6374 BinaryOperator::Opcode Opc = ConvertTokenKindToBinaryOpcode(Kind); 6375 Expr *lhs = LHS.takeAs<Expr>(), *rhs = RHS.takeAs<Expr>(); 6376 6377 assert((lhs != 0) && "ActOnBinOp(): missing left expression"); 6378 assert((rhs != 0) && "ActOnBinOp(): missing right expression"); 6379 6380 // Emit warnings for tricky precedence issues, e.g. "bitfield & 0x4 == 0" 6381 DiagnoseBinOpPrecedence(*this, Opc, TokLoc, lhs, rhs); 6382 6383 return BuildBinOp(S, TokLoc, Opc, lhs, rhs); 6384} 6385 6386Action::OwningExprResult Sema::BuildBinOp(Scope *S, SourceLocation OpLoc, 6387 BinaryOperator::Opcode Opc, 6388 Expr *lhs, Expr *rhs) { 6389 if (getLangOptions().CPlusPlus && 6390 (lhs->getType()->isOverloadableType() || 6391 rhs->getType()->isOverloadableType())) { 6392 // Find all of the overloaded operators visible from this 6393 // point. We perform both an operator-name lookup from the local 6394 // scope and an argument-dependent lookup based on the types of 6395 // the arguments. 6396 UnresolvedSet<16> Functions; 6397 OverloadedOperatorKind OverOp = BinaryOperator::getOverloadedOperator(Opc); 6398 if (S && OverOp != OO_None) 6399 LookupOverloadedOperatorName(OverOp, S, lhs->getType(), rhs->getType(), 6400 Functions); 6401 6402 // Build the (potentially-overloaded, potentially-dependent) 6403 // binary operation. 6404 return CreateOverloadedBinOp(OpLoc, Opc, Functions, lhs, rhs); 6405 } 6406 6407 // Build a built-in binary operation. 6408 return CreateBuiltinBinOp(OpLoc, Opc, lhs, rhs); 6409} 6410 6411Action::OwningExprResult Sema::CreateBuiltinUnaryOp(SourceLocation OpLoc, 6412 unsigned OpcIn, 6413 ExprArg InputArg) { 6414 UnaryOperator::Opcode Opc = static_cast<UnaryOperator::Opcode>(OpcIn); 6415 6416 // FIXME: Input is modified below, but InputArg is not updated appropriately. 6417 Expr *Input = (Expr *)InputArg.get(); 6418 QualType resultType; 6419 switch (Opc) { 6420 case UnaryOperator::OffsetOf: 6421 assert(false && "Invalid unary operator"); 6422 break; 6423 6424 case UnaryOperator::PreInc: 6425 case UnaryOperator::PreDec: 6426 case UnaryOperator::PostInc: 6427 case UnaryOperator::PostDec: 6428 resultType = CheckIncrementDecrementOperand(Input, OpLoc, 6429 Opc == UnaryOperator::PreInc || 6430 Opc == UnaryOperator::PostInc); 6431 break; 6432 case UnaryOperator::AddrOf: 6433 resultType = CheckAddressOfOperand(Input, OpLoc); 6434 break; 6435 case UnaryOperator::Deref: 6436 DefaultFunctionArrayLvalueConversion(Input); 6437 resultType = CheckIndirectionOperand(Input, OpLoc); 6438 break; 6439 case UnaryOperator::Plus: 6440 case UnaryOperator::Minus: 6441 UsualUnaryConversions(Input); 6442 resultType = Input->getType(); 6443 if (resultType->isDependentType()) 6444 break; 6445 if (resultType->isArithmeticType()) // C99 6.5.3.3p1 6446 break; 6447 else if (getLangOptions().CPlusPlus && // C++ [expr.unary.op]p6-7 6448 resultType->isEnumeralType()) 6449 break; 6450 else if (getLangOptions().CPlusPlus && // C++ [expr.unary.op]p6 6451 Opc == UnaryOperator::Plus && 6452 resultType->isPointerType()) 6453 break; 6454 6455 return ExprError(Diag(OpLoc, diag::err_typecheck_unary_expr) 6456 << resultType << Input->getSourceRange()); 6457 case UnaryOperator::Not: // bitwise complement 6458 UsualUnaryConversions(Input); 6459 resultType = Input->getType(); 6460 if (resultType->isDependentType()) 6461 break; 6462 // C99 6.5.3.3p1. We allow complex int and float as a GCC extension. 6463 if (resultType->isComplexType() || resultType->isComplexIntegerType()) 6464 // C99 does not support '~' for complex conjugation. 6465 Diag(OpLoc, diag::ext_integer_complement_complex) 6466 << resultType << Input->getSourceRange(); 6467 else if (!resultType->isIntegerType()) 6468 return ExprError(Diag(OpLoc, diag::err_typecheck_unary_expr) 6469 << resultType << Input->getSourceRange()); 6470 break; 6471 case UnaryOperator::LNot: // logical negation 6472 // Unlike +/-/~, integer promotions aren't done here (C99 6.5.3.3p5). 6473 DefaultFunctionArrayLvalueConversion(Input); 6474 resultType = Input->getType(); 6475 if (resultType->isDependentType()) 6476 break; 6477 if (!resultType->isScalarType()) // C99 6.5.3.3p1 6478 return ExprError(Diag(OpLoc, diag::err_typecheck_unary_expr) 6479 << resultType << Input->getSourceRange()); 6480 // LNot always has type int. C99 6.5.3.3p5. 6481 // In C++, it's bool. C++ 5.3.1p8 6482 resultType = getLangOptions().CPlusPlus ? Context.BoolTy : Context.IntTy; 6483 break; 6484 case UnaryOperator::Real: 6485 case UnaryOperator::Imag: 6486 resultType = CheckRealImagOperand(Input, OpLoc, Opc == UnaryOperator::Real); 6487 break; 6488 case UnaryOperator::Extension: 6489 resultType = Input->getType(); 6490 break; 6491 } 6492 if (resultType.isNull()) 6493 return ExprError(); 6494 6495 InputArg.release(); 6496 return Owned(new (Context) UnaryOperator(Input, Opc, resultType, OpLoc)); 6497} 6498 6499Action::OwningExprResult Sema::BuildUnaryOp(Scope *S, SourceLocation OpLoc, 6500 UnaryOperator::Opcode Opc, 6501 ExprArg input) { 6502 Expr *Input = (Expr*)input.get(); 6503 if (getLangOptions().CPlusPlus && Input->getType()->isOverloadableType() && 6504 Opc != UnaryOperator::Extension) { 6505 // Find all of the overloaded operators visible from this 6506 // point. We perform both an operator-name lookup from the local 6507 // scope and an argument-dependent lookup based on the types of 6508 // the arguments. 6509 UnresolvedSet<16> Functions; 6510 OverloadedOperatorKind OverOp = UnaryOperator::getOverloadedOperator(Opc); 6511 if (S && OverOp != OO_None) 6512 LookupOverloadedOperatorName(OverOp, S, Input->getType(), QualType(), 6513 Functions); 6514 6515 return CreateOverloadedUnaryOp(OpLoc, Opc, Functions, move(input)); 6516 } 6517 6518 return CreateBuiltinUnaryOp(OpLoc, Opc, move(input)); 6519} 6520 6521// Unary Operators. 'Tok' is the token for the operator. 6522Action::OwningExprResult Sema::ActOnUnaryOp(Scope *S, SourceLocation OpLoc, 6523 tok::TokenKind Op, ExprArg input) { 6524 return BuildUnaryOp(S, OpLoc, ConvertTokenKindToUnaryOpcode(Op), move(input)); 6525} 6526 6527/// ActOnAddrLabel - Parse the GNU address of label extension: "&&foo". 6528Sema::OwningExprResult Sema::ActOnAddrLabel(SourceLocation OpLoc, 6529 SourceLocation LabLoc, 6530 IdentifierInfo *LabelII) { 6531 // Look up the record for this label identifier. 6532 LabelStmt *&LabelDecl = getLabelMap()[LabelII]; 6533 6534 // If we haven't seen this label yet, create a forward reference. It 6535 // will be validated and/or cleaned up in ActOnFinishFunctionBody. 6536 if (LabelDecl == 0) 6537 LabelDecl = new (Context) LabelStmt(LabLoc, LabelII, 0); 6538 6539 // Create the AST node. The address of a label always has type 'void*'. 6540 return Owned(new (Context) AddrLabelExpr(OpLoc, LabLoc, LabelDecl, 6541 Context.getPointerType(Context.VoidTy))); 6542} 6543 6544Sema::OwningExprResult 6545Sema::ActOnStmtExpr(SourceLocation LPLoc, StmtArg substmt, 6546 SourceLocation RPLoc) { // "({..})" 6547 Stmt *SubStmt = static_cast<Stmt*>(substmt.get()); 6548 assert(SubStmt && isa<CompoundStmt>(SubStmt) && "Invalid action invocation!"); 6549 CompoundStmt *Compound = cast<CompoundStmt>(SubStmt); 6550 6551 bool isFileScope 6552 = (getCurFunctionOrMethodDecl() == 0) && (getCurBlock() == 0); 6553 if (isFileScope) 6554 return ExprError(Diag(LPLoc, diag::err_stmtexpr_file_scope)); 6555 6556 // FIXME: there are a variety of strange constraints to enforce here, for 6557 // example, it is not possible to goto into a stmt expression apparently. 6558 // More semantic analysis is needed. 6559 6560 // If there are sub stmts in the compound stmt, take the type of the last one 6561 // as the type of the stmtexpr. 6562 QualType Ty = Context.VoidTy; 6563 6564 if (!Compound->body_empty()) { 6565 Stmt *LastStmt = Compound->body_back(); 6566 // If LastStmt is a label, skip down through into the body. 6567 while (LabelStmt *Label = dyn_cast<LabelStmt>(LastStmt)) 6568 LastStmt = Label->getSubStmt(); 6569 6570 if (Expr *LastExpr = dyn_cast<Expr>(LastStmt)) 6571 Ty = LastExpr->getType(); 6572 } 6573 6574 // FIXME: Check that expression type is complete/non-abstract; statement 6575 // expressions are not lvalues. 6576 6577 substmt.release(); 6578 return Owned(new (Context) StmtExpr(Compound, Ty, LPLoc, RPLoc)); 6579} 6580 6581Sema::OwningExprResult Sema::ActOnBuiltinOffsetOf(Scope *S, 6582 SourceLocation BuiltinLoc, 6583 SourceLocation TypeLoc, 6584 TypeTy *argty, 6585 OffsetOfComponent *CompPtr, 6586 unsigned NumComponents, 6587 SourceLocation RPLoc) { 6588 // FIXME: This function leaks all expressions in the offset components on 6589 // error. 6590 // FIXME: Preserve type source info. 6591 QualType ArgTy = GetTypeFromParser(argty); 6592 assert(!ArgTy.isNull() && "Missing type argument!"); 6593 6594 bool Dependent = ArgTy->isDependentType(); 6595 6596 // We must have at least one component that refers to the type, and the first 6597 // one is known to be a field designator. Verify that the ArgTy represents 6598 // a struct/union/class. 6599 if (!Dependent && !ArgTy->isRecordType()) 6600 return ExprError(Diag(TypeLoc, diag::err_offsetof_record_type) << ArgTy); 6601 6602 // FIXME: Type must be complete per C99 7.17p3 because a declaring a variable 6603 // with an incomplete type would be illegal. 6604 6605 // Otherwise, create a null pointer as the base, and iteratively process 6606 // the offsetof designators. 6607 QualType ArgTyPtr = Context.getPointerType(ArgTy); 6608 Expr* Res = new (Context) ImplicitValueInitExpr(ArgTyPtr); 6609 Res = new (Context) UnaryOperator(Res, UnaryOperator::Deref, 6610 ArgTy, SourceLocation()); 6611 6612 // offsetof with non-identifier designators (e.g. "offsetof(x, a.b[c])") are a 6613 // GCC extension, diagnose them. 6614 // FIXME: This diagnostic isn't actually visible because the location is in 6615 // a system header! 6616 if (NumComponents != 1) 6617 Diag(BuiltinLoc, diag::ext_offsetof_extended_field_designator) 6618 << SourceRange(CompPtr[1].LocStart, CompPtr[NumComponents-1].LocEnd); 6619 6620 if (!Dependent) { 6621 bool DidWarnAboutNonPOD = false; 6622 6623 if (RequireCompleteType(TypeLoc, Res->getType(), 6624 diag::err_offsetof_incomplete_type)) 6625 return ExprError(); 6626 6627 // FIXME: Dependent case loses a lot of information here. And probably 6628 // leaks like a sieve. 6629 for (unsigned i = 0; i != NumComponents; ++i) { 6630 const OffsetOfComponent &OC = CompPtr[i]; 6631 if (OC.isBrackets) { 6632 // Offset of an array sub-field. TODO: Should we allow vector elements? 6633 const ArrayType *AT = Context.getAsArrayType(Res->getType()); 6634 if (!AT) { 6635 Res->Destroy(Context); 6636 return ExprError(Diag(OC.LocEnd, diag::err_offsetof_array_type) 6637 << Res->getType()); 6638 } 6639 6640 // FIXME: C++: Verify that operator[] isn't overloaded. 6641 6642 // Promote the array so it looks more like a normal array subscript 6643 // expression. 6644 DefaultFunctionArrayLvalueConversion(Res); 6645 6646 // C99 6.5.2.1p1 6647 Expr *Idx = static_cast<Expr*>(OC.U.E); 6648 // FIXME: Leaks Res 6649 if (!Idx->isTypeDependent() && !Idx->getType()->isIntegerType()) 6650 return ExprError(Diag(Idx->getLocStart(), 6651 diag::err_typecheck_subscript_not_integer) 6652 << Idx->getSourceRange()); 6653 6654 Res = new (Context) ArraySubscriptExpr(Res, Idx, AT->getElementType(), 6655 OC.LocEnd); 6656 continue; 6657 } 6658 6659 const RecordType *RC = Res->getType()->getAs<RecordType>(); 6660 if (!RC) { 6661 Res->Destroy(Context); 6662 return ExprError(Diag(OC.LocEnd, diag::err_offsetof_record_type) 6663 << Res->getType()); 6664 } 6665 6666 // Get the decl corresponding to this. 6667 RecordDecl *RD = RC->getDecl(); 6668 if (CXXRecordDecl *CRD = dyn_cast<CXXRecordDecl>(RD)) { 6669 if (!CRD->isPOD() && !DidWarnAboutNonPOD && 6670 DiagRuntimeBehavior(BuiltinLoc, 6671 PDiag(diag::warn_offsetof_non_pod_type) 6672 << SourceRange(CompPtr[0].LocStart, OC.LocEnd) 6673 << Res->getType())) 6674 DidWarnAboutNonPOD = true; 6675 } 6676 6677 LookupResult R(*this, OC.U.IdentInfo, OC.LocStart, LookupMemberName); 6678 LookupQualifiedName(R, RD); 6679 6680 FieldDecl *MemberDecl = R.getAsSingle<FieldDecl>(); 6681 // FIXME: Leaks Res 6682 if (!MemberDecl) 6683 return ExprError(Diag(BuiltinLoc, diag::err_no_member) 6684 << OC.U.IdentInfo << RD << SourceRange(OC.LocStart, OC.LocEnd)); 6685 6686 // FIXME: C++: Verify that MemberDecl isn't a static field. 6687 // FIXME: Verify that MemberDecl isn't a bitfield. 6688 if (cast<RecordDecl>(MemberDecl->getDeclContext())->isAnonymousStructOrUnion()) { 6689 Res = BuildAnonymousStructUnionMemberReference( 6690 OC.LocEnd, MemberDecl, Res, OC.LocEnd).takeAs<Expr>(); 6691 } else { 6692 PerformObjectMemberConversion(Res, /*Qualifier=*/0, 6693 *R.begin(), MemberDecl); 6694 // MemberDecl->getType() doesn't get the right qualifiers, but it 6695 // doesn't matter here. 6696 Res = new (Context) MemberExpr(Res, false, MemberDecl, OC.LocEnd, 6697 MemberDecl->getType().getNonReferenceType()); 6698 } 6699 } 6700 } 6701 6702 return Owned(new (Context) UnaryOperator(Res, UnaryOperator::OffsetOf, 6703 Context.getSizeType(), BuiltinLoc)); 6704} 6705 6706 6707Sema::OwningExprResult Sema::ActOnTypesCompatibleExpr(SourceLocation BuiltinLoc, 6708 TypeTy *arg1,TypeTy *arg2, 6709 SourceLocation RPLoc) { 6710 // FIXME: Preserve type source info. 6711 QualType argT1 = GetTypeFromParser(arg1); 6712 QualType argT2 = GetTypeFromParser(arg2); 6713 6714 assert((!argT1.isNull() && !argT2.isNull()) && "Missing type argument(s)"); 6715 6716 if (getLangOptions().CPlusPlus) { 6717 Diag(BuiltinLoc, diag::err_types_compatible_p_in_cplusplus) 6718 << SourceRange(BuiltinLoc, RPLoc); 6719 return ExprError(); 6720 } 6721 6722 return Owned(new (Context) TypesCompatibleExpr(Context.IntTy, BuiltinLoc, 6723 argT1, argT2, RPLoc)); 6724} 6725 6726Sema::OwningExprResult Sema::ActOnChooseExpr(SourceLocation BuiltinLoc, 6727 ExprArg cond, 6728 ExprArg expr1, ExprArg expr2, 6729 SourceLocation RPLoc) { 6730 Expr *CondExpr = static_cast<Expr*>(cond.get()); 6731 Expr *LHSExpr = static_cast<Expr*>(expr1.get()); 6732 Expr *RHSExpr = static_cast<Expr*>(expr2.get()); 6733 6734 assert((CondExpr && LHSExpr && RHSExpr) && "Missing type argument(s)"); 6735 6736 QualType resType; 6737 bool ValueDependent = false; 6738 if (CondExpr->isTypeDependent() || CondExpr->isValueDependent()) { 6739 resType = Context.DependentTy; 6740 ValueDependent = true; 6741 } else { 6742 // The conditional expression is required to be a constant expression. 6743 llvm::APSInt condEval(32); 6744 SourceLocation ExpLoc; 6745 if (!CondExpr->isIntegerConstantExpr(condEval, Context, &ExpLoc)) 6746 return ExprError(Diag(ExpLoc, 6747 diag::err_typecheck_choose_expr_requires_constant) 6748 << CondExpr->getSourceRange()); 6749 6750 // If the condition is > zero, then the AST type is the same as the LSHExpr. 6751 resType = condEval.getZExtValue() ? LHSExpr->getType() : RHSExpr->getType(); 6752 ValueDependent = condEval.getZExtValue() ? LHSExpr->isValueDependent() 6753 : RHSExpr->isValueDependent(); 6754 } 6755 6756 cond.release(); expr1.release(); expr2.release(); 6757 return Owned(new (Context) ChooseExpr(BuiltinLoc, CondExpr, LHSExpr, RHSExpr, 6758 resType, RPLoc, 6759 resType->isDependentType(), 6760 ValueDependent)); 6761} 6762 6763//===----------------------------------------------------------------------===// 6764// Clang Extensions. 6765//===----------------------------------------------------------------------===// 6766 6767/// ActOnBlockStart - This callback is invoked when a block literal is started. 6768void Sema::ActOnBlockStart(SourceLocation CaretLoc, Scope *BlockScope) { 6769 BlockDecl *Block = BlockDecl::Create(Context, CurContext, CaretLoc); 6770 PushBlockScope(BlockScope, Block); 6771 CurContext->addDecl(Block); 6772 PushDeclContext(BlockScope, Block); 6773} 6774 6775void Sema::ActOnBlockArguments(Declarator &ParamInfo, Scope *CurScope) { 6776 assert(ParamInfo.getIdentifier()==0 && "block-id should have no identifier!"); 6777 BlockScopeInfo *CurBlock = getCurBlock(); 6778 6779 if (ParamInfo.getNumTypeObjects() == 0 6780 || ParamInfo.getTypeObject(0).Kind != DeclaratorChunk::Function) { 6781 ProcessDeclAttributes(CurScope, CurBlock->TheDecl, ParamInfo); 6782 QualType T = GetTypeForDeclarator(ParamInfo, CurScope); 6783 6784 if (T->isArrayType()) { 6785 Diag(ParamInfo.getSourceRange().getBegin(), 6786 diag::err_block_returns_array); 6787 return; 6788 } 6789 6790 // The parameter list is optional, if there was none, assume (). 6791 if (!T->isFunctionType()) 6792 T = Context.getFunctionType(T, 0, 0, false, 0, false, false, 0, 0, 6793 FunctionType::ExtInfo()); 6794 6795 CurBlock->hasPrototype = true; 6796 CurBlock->isVariadic = false; 6797 // Check for a valid sentinel attribute on this block. 6798 if (CurBlock->TheDecl->getAttr<SentinelAttr>()) { 6799 Diag(ParamInfo.getAttributes()->getLoc(), 6800 diag::warn_attribute_sentinel_not_variadic) << 1; 6801 // FIXME: remove the attribute. 6802 } 6803 QualType RetTy = T.getTypePtr()->getAs<FunctionType>()->getResultType(); 6804 6805 // Do not allow returning a objc interface by-value. 6806 if (RetTy->isObjCInterfaceType()) { 6807 Diag(ParamInfo.getSourceRange().getBegin(), 6808 diag::err_object_cannot_be_passed_returned_by_value) << 0 << RetTy; 6809 return; 6810 } 6811 6812 CurBlock->ReturnType = RetTy; 6813 return; 6814 } 6815 6816 // Analyze arguments to block. 6817 assert(ParamInfo.getTypeObject(0).Kind == DeclaratorChunk::Function && 6818 "Not a function declarator!"); 6819 DeclaratorChunk::FunctionTypeInfo &FTI = ParamInfo.getTypeObject(0).Fun; 6820 6821 CurBlock->hasPrototype = FTI.hasPrototype; 6822 CurBlock->isVariadic = true; 6823 6824 // Check for C99 6.7.5.3p10 - foo(void) is a non-varargs function that takes 6825 // no arguments, not a function that takes a single void argument. 6826 if (FTI.hasPrototype && 6827 FTI.NumArgs == 1 && !FTI.isVariadic && FTI.ArgInfo[0].Ident == 0 && 6828 (!FTI.ArgInfo[0].Param.getAs<ParmVarDecl>()->getType().getCVRQualifiers()&& 6829 FTI.ArgInfo[0].Param.getAs<ParmVarDecl>()->getType()->isVoidType())) { 6830 // empty arg list, don't push any params. 6831 CurBlock->isVariadic = false; 6832 } else if (FTI.hasPrototype) { 6833 for (unsigned i = 0, e = FTI.NumArgs; i != e; ++i) { 6834 ParmVarDecl *Param = FTI.ArgInfo[i].Param.getAs<ParmVarDecl>(); 6835 if (Param->getIdentifier() == 0 && 6836 !Param->isImplicit() && 6837 !Param->isInvalidDecl() && 6838 !getLangOptions().CPlusPlus) 6839 Diag(Param->getLocation(), diag::err_parameter_name_omitted); 6840 CurBlock->Params.push_back(Param); 6841 } 6842 CurBlock->isVariadic = FTI.isVariadic; 6843 } 6844 CurBlock->TheDecl->setParams(CurBlock->Params.data(), 6845 CurBlock->Params.size()); 6846 CurBlock->TheDecl->setIsVariadic(CurBlock->isVariadic); 6847 ProcessDeclAttributes(CurScope, CurBlock->TheDecl, ParamInfo); 6848 6849 bool ShouldCheckShadow = 6850 Diags.getDiagnosticLevel(diag::warn_decl_shadow) != Diagnostic::Ignored; 6851 6852 for (BlockDecl::param_iterator AI = CurBlock->TheDecl->param_begin(), 6853 E = CurBlock->TheDecl->param_end(); AI != E; ++AI) { 6854 (*AI)->setOwningFunction(CurBlock->TheDecl); 6855 6856 // If this has an identifier, add it to the scope stack. 6857 if ((*AI)->getIdentifier()) { 6858 if (ShouldCheckShadow) 6859 CheckShadow(CurBlock->TheScope, *AI); 6860 6861 PushOnScopeChains(*AI, CurBlock->TheScope); 6862 } 6863 } 6864 6865 // Check for a valid sentinel attribute on this block. 6866 if (!CurBlock->isVariadic && 6867 CurBlock->TheDecl->getAttr<SentinelAttr>()) { 6868 Diag(ParamInfo.getAttributes()->getLoc(), 6869 diag::warn_attribute_sentinel_not_variadic) << 1; 6870 // FIXME: remove the attribute. 6871 } 6872 6873 // Analyze the return type. 6874 QualType T = GetTypeForDeclarator(ParamInfo, CurScope); 6875 QualType RetTy = T->getAs<FunctionType>()->getResultType(); 6876 6877 // Do not allow returning a objc interface by-value. 6878 if (RetTy->isObjCInterfaceType()) { 6879 Diag(ParamInfo.getSourceRange().getBegin(), 6880 diag::err_object_cannot_be_passed_returned_by_value) << 0 << RetTy; 6881 } else if (!RetTy->isDependentType()) 6882 CurBlock->ReturnType = RetTy; 6883} 6884 6885/// ActOnBlockError - If there is an error parsing a block, this callback 6886/// is invoked to pop the information about the block from the action impl. 6887void Sema::ActOnBlockError(SourceLocation CaretLoc, Scope *CurScope) { 6888 // Pop off CurBlock, handle nested blocks. 6889 PopDeclContext(); 6890 PopFunctionOrBlockScope(); 6891 // FIXME: Delete the ParmVarDecl objects as well??? 6892} 6893 6894/// ActOnBlockStmtExpr - This is called when the body of a block statement 6895/// literal was successfully completed. ^(int x){...} 6896Sema::OwningExprResult Sema::ActOnBlockStmtExpr(SourceLocation CaretLoc, 6897 StmtArg body, Scope *CurScope) { 6898 // If blocks are disabled, emit an error. 6899 if (!LangOpts.Blocks) 6900 Diag(CaretLoc, diag::err_blocks_disable); 6901 6902 BlockScopeInfo *BSI = cast<BlockScopeInfo>(FunctionScopes.back()); 6903 6904 PopDeclContext(); 6905 6906 QualType RetTy = Context.VoidTy; 6907 if (!BSI->ReturnType.isNull()) 6908 RetTy = BSI->ReturnType; 6909 6910 llvm::SmallVector<QualType, 8> ArgTypes; 6911 for (unsigned i = 0, e = BSI->Params.size(); i != e; ++i) 6912 ArgTypes.push_back(BSI->Params[i]->getType()); 6913 6914 bool NoReturn = BSI->TheDecl->getAttr<NoReturnAttr>(); 6915 QualType BlockTy; 6916 if (!BSI->hasPrototype) 6917 BlockTy = Context.getFunctionType(RetTy, 0, 0, false, 0, false, false, 0, 0, 6918 FunctionType::ExtInfo(NoReturn, 0, CC_Default)); 6919 else 6920 BlockTy = Context.getFunctionType(RetTy, ArgTypes.data(), ArgTypes.size(), 6921 BSI->isVariadic, 0, false, false, 0, 0, 6922 FunctionType::ExtInfo(NoReturn, 0, CC_Default)); 6923 6924 // FIXME: Check that return/parameter types are complete/non-abstract 6925 DiagnoseUnusedParameters(BSI->Params.begin(), BSI->Params.end()); 6926 BlockTy = Context.getBlockPointerType(BlockTy); 6927 6928 // If needed, diagnose invalid gotos and switches in the block. 6929 if (FunctionNeedsScopeChecking() && !hasAnyErrorsInThisFunction()) 6930 DiagnoseInvalidJumps(static_cast<CompoundStmt*>(body.get())); 6931 6932 BSI->TheDecl->setBody(body.takeAs<CompoundStmt>()); 6933 6934 bool Good = true; 6935 // Check goto/label use. 6936 for (llvm::DenseMap<IdentifierInfo*, LabelStmt*>::iterator 6937 I = BSI->LabelMap.begin(), E = BSI->LabelMap.end(); I != E; ++I) { 6938 LabelStmt *L = I->second; 6939 6940 // Verify that we have no forward references left. If so, there was a goto 6941 // or address of a label taken, but no definition of it. 6942 if (L->getSubStmt() != 0) 6943 continue; 6944 6945 // Emit error. 6946 Diag(L->getIdentLoc(), diag::err_undeclared_label_use) << L->getName(); 6947 Good = false; 6948 } 6949 if (!Good) { 6950 PopFunctionOrBlockScope(); 6951 return ExprError(); 6952 } 6953 6954 // Issue any analysis-based warnings. 6955 const sema::AnalysisBasedWarnings::Policy &WP = 6956 AnalysisWarnings.getDefaultPolicy(); 6957 AnalysisWarnings.IssueWarnings(WP, BSI->TheDecl, BlockTy); 6958 6959 Expr *Result = new (Context) BlockExpr(BSI->TheDecl, BlockTy, 6960 BSI->hasBlockDeclRefExprs); 6961 PopFunctionOrBlockScope(); 6962 return Owned(Result); 6963} 6964 6965Sema::OwningExprResult Sema::ActOnVAArg(SourceLocation BuiltinLoc, 6966 ExprArg expr, TypeTy *type, 6967 SourceLocation RPLoc) { 6968 QualType T = GetTypeFromParser(type); 6969 Expr *E = static_cast<Expr*>(expr.get()); 6970 Expr *OrigExpr = E; 6971 6972 InitBuiltinVaListType(); 6973 6974 // Get the va_list type 6975 QualType VaListType = Context.getBuiltinVaListType(); 6976 if (VaListType->isArrayType()) { 6977 // Deal with implicit array decay; for example, on x86-64, 6978 // va_list is an array, but it's supposed to decay to 6979 // a pointer for va_arg. 6980 VaListType = Context.getArrayDecayedType(VaListType); 6981 // Make sure the input expression also decays appropriately. 6982 UsualUnaryConversions(E); 6983 } else { 6984 // Otherwise, the va_list argument must be an l-value because 6985 // it is modified by va_arg. 6986 if (!E->isTypeDependent() && 6987 CheckForModifiableLvalue(E, BuiltinLoc, *this)) 6988 return ExprError(); 6989 } 6990 6991 if (!E->isTypeDependent() && 6992 !Context.hasSameType(VaListType, E->getType())) { 6993 return ExprError(Diag(E->getLocStart(), 6994 diag::err_first_argument_to_va_arg_not_of_type_va_list) 6995 << OrigExpr->getType() << E->getSourceRange()); 6996 } 6997 6998 // FIXME: Check that type is complete/non-abstract 6999 // FIXME: Warn if a non-POD type is passed in. 7000 7001 expr.release(); 7002 return Owned(new (Context) VAArgExpr(BuiltinLoc, E, T.getNonReferenceType(), 7003 RPLoc)); 7004} 7005 7006Sema::OwningExprResult Sema::ActOnGNUNullExpr(SourceLocation TokenLoc) { 7007 // The type of __null will be int or long, depending on the size of 7008 // pointers on the target. 7009 QualType Ty; 7010 if (Context.Target.getPointerWidth(0) == Context.Target.getIntWidth()) 7011 Ty = Context.IntTy; 7012 else 7013 Ty = Context.LongTy; 7014 7015 return Owned(new (Context) GNUNullExpr(Ty, TokenLoc)); 7016} 7017 7018static void MakeObjCStringLiteralFixItHint(Sema& SemaRef, QualType DstType, 7019 Expr *SrcExpr, FixItHint &Hint) { 7020 if (!SemaRef.getLangOptions().ObjC1) 7021 return; 7022 7023 const ObjCObjectPointerType *PT = DstType->getAs<ObjCObjectPointerType>(); 7024 if (!PT) 7025 return; 7026 7027 // Check if the destination is of type 'id'. 7028 if (!PT->isObjCIdType()) { 7029 // Check if the destination is the 'NSString' interface. 7030 const ObjCInterfaceDecl *ID = PT->getInterfaceDecl(); 7031 if (!ID || !ID->getIdentifier()->isStr("NSString")) 7032 return; 7033 } 7034 7035 // Strip off any parens and casts. 7036 StringLiteral *SL = dyn_cast<StringLiteral>(SrcExpr->IgnoreParenCasts()); 7037 if (!SL || SL->isWide()) 7038 return; 7039 7040 Hint = FixItHint::CreateInsertion(SL->getLocStart(), "@"); 7041} 7042 7043bool Sema::DiagnoseAssignmentResult(AssignConvertType ConvTy, 7044 SourceLocation Loc, 7045 QualType DstType, QualType SrcType, 7046 Expr *SrcExpr, AssignmentAction Action, 7047 bool *Complained) { 7048 if (Complained) 7049 *Complained = false; 7050 7051 // Decode the result (notice that AST's are still created for extensions). 7052 bool isInvalid = false; 7053 unsigned DiagKind; 7054 FixItHint Hint; 7055 7056 switch (ConvTy) { 7057 default: assert(0 && "Unknown conversion type"); 7058 case Compatible: return false; 7059 case PointerToInt: 7060 DiagKind = diag::ext_typecheck_convert_pointer_int; 7061 break; 7062 case IntToPointer: 7063 DiagKind = diag::ext_typecheck_convert_int_pointer; 7064 break; 7065 case IncompatiblePointer: 7066 MakeObjCStringLiteralFixItHint(*this, DstType, SrcExpr, Hint); 7067 DiagKind = diag::ext_typecheck_convert_incompatible_pointer; 7068 break; 7069 case IncompatiblePointerSign: 7070 DiagKind = diag::ext_typecheck_convert_incompatible_pointer_sign; 7071 break; 7072 case FunctionVoidPointer: 7073 DiagKind = diag::ext_typecheck_convert_pointer_void_func; 7074 break; 7075 case CompatiblePointerDiscardsQualifiers: 7076 // If the qualifiers lost were because we were applying the 7077 // (deprecated) C++ conversion from a string literal to a char* 7078 // (or wchar_t*), then there was no error (C++ 4.2p2). FIXME: 7079 // Ideally, this check would be performed in 7080 // CheckPointerTypesForAssignment. However, that would require a 7081 // bit of refactoring (so that the second argument is an 7082 // expression, rather than a type), which should be done as part 7083 // of a larger effort to fix CheckPointerTypesForAssignment for 7084 // C++ semantics. 7085 if (getLangOptions().CPlusPlus && 7086 IsStringLiteralToNonConstPointerConversion(SrcExpr, DstType)) 7087 return false; 7088 DiagKind = diag::ext_typecheck_convert_discards_qualifiers; 7089 break; 7090 case IncompatibleNestedPointerQualifiers: 7091 DiagKind = diag::ext_nested_pointer_qualifier_mismatch; 7092 break; 7093 case IntToBlockPointer: 7094 DiagKind = diag::err_int_to_block_pointer; 7095 break; 7096 case IncompatibleBlockPointer: 7097 DiagKind = diag::err_typecheck_convert_incompatible_block_pointer; 7098 break; 7099 case IncompatibleObjCQualifiedId: 7100 // FIXME: Diagnose the problem in ObjCQualifiedIdTypesAreCompatible, since 7101 // it can give a more specific diagnostic. 7102 DiagKind = diag::warn_incompatible_qualified_id; 7103 break; 7104 case IncompatibleVectors: 7105 DiagKind = diag::warn_incompatible_vectors; 7106 break; 7107 case Incompatible: 7108 DiagKind = diag::err_typecheck_convert_incompatible; 7109 isInvalid = true; 7110 break; 7111 } 7112 7113 QualType FirstType, SecondType; 7114 switch (Action) { 7115 case AA_Assigning: 7116 case AA_Initializing: 7117 // The destination type comes first. 7118 FirstType = DstType; 7119 SecondType = SrcType; 7120 break; 7121 7122 case AA_Returning: 7123 case AA_Passing: 7124 case AA_Converting: 7125 case AA_Sending: 7126 case AA_Casting: 7127 // The source type comes first. 7128 FirstType = SrcType; 7129 SecondType = DstType; 7130 break; 7131 } 7132 7133 Diag(Loc, DiagKind) << FirstType << SecondType << Action 7134 << SrcExpr->getSourceRange() << Hint; 7135 if (Complained) 7136 *Complained = true; 7137 return isInvalid; 7138} 7139 7140bool Sema::VerifyIntegerConstantExpression(const Expr *E, llvm::APSInt *Result){ 7141 llvm::APSInt ICEResult; 7142 if (E->isIntegerConstantExpr(ICEResult, Context)) { 7143 if (Result) 7144 *Result = ICEResult; 7145 return false; 7146 } 7147 7148 Expr::EvalResult EvalResult; 7149 7150 if (!E->Evaluate(EvalResult, Context) || !EvalResult.Val.isInt() || 7151 EvalResult.HasSideEffects) { 7152 Diag(E->getExprLoc(), diag::err_expr_not_ice) << E->getSourceRange(); 7153 7154 if (EvalResult.Diag) { 7155 // We only show the note if it's not the usual "invalid subexpression" 7156 // or if it's actually in a subexpression. 7157 if (EvalResult.Diag != diag::note_invalid_subexpr_in_ice || 7158 E->IgnoreParens() != EvalResult.DiagExpr->IgnoreParens()) 7159 Diag(EvalResult.DiagLoc, EvalResult.Diag); 7160 } 7161 7162 return true; 7163 } 7164 7165 Diag(E->getExprLoc(), diag::ext_expr_not_ice) << 7166 E->getSourceRange(); 7167 7168 if (EvalResult.Diag && 7169 Diags.getDiagnosticLevel(diag::ext_expr_not_ice) != Diagnostic::Ignored) 7170 Diag(EvalResult.DiagLoc, EvalResult.Diag); 7171 7172 if (Result) 7173 *Result = EvalResult.Val.getInt(); 7174 return false; 7175} 7176 7177void 7178Sema::PushExpressionEvaluationContext(ExpressionEvaluationContext NewContext) { 7179 ExprEvalContexts.push_back( 7180 ExpressionEvaluationContextRecord(NewContext, ExprTemporaries.size())); 7181} 7182 7183void 7184Sema::PopExpressionEvaluationContext() { 7185 // Pop the current expression evaluation context off the stack. 7186 ExpressionEvaluationContextRecord Rec = ExprEvalContexts.back(); 7187 ExprEvalContexts.pop_back(); 7188 7189 if (Rec.Context == PotentiallyPotentiallyEvaluated) { 7190 if (Rec.PotentiallyReferenced) { 7191 // Mark any remaining declarations in the current position of the stack 7192 // as "referenced". If they were not meant to be referenced, semantic 7193 // analysis would have eliminated them (e.g., in ActOnCXXTypeId). 7194 for (PotentiallyReferencedDecls::iterator 7195 I = Rec.PotentiallyReferenced->begin(), 7196 IEnd = Rec.PotentiallyReferenced->end(); 7197 I != IEnd; ++I) 7198 MarkDeclarationReferenced(I->first, I->second); 7199 } 7200 7201 if (Rec.PotentiallyDiagnosed) { 7202 // Emit any pending diagnostics. 7203 for (PotentiallyEmittedDiagnostics::iterator 7204 I = Rec.PotentiallyDiagnosed->begin(), 7205 IEnd = Rec.PotentiallyDiagnosed->end(); 7206 I != IEnd; ++I) 7207 Diag(I->first, I->second); 7208 } 7209 } 7210 7211 // When are coming out of an unevaluated context, clear out any 7212 // temporaries that we may have created as part of the evaluation of 7213 // the expression in that context: they aren't relevant because they 7214 // will never be constructed. 7215 if (Rec.Context == Unevaluated && 7216 ExprTemporaries.size() > Rec.NumTemporaries) 7217 ExprTemporaries.erase(ExprTemporaries.begin() + Rec.NumTemporaries, 7218 ExprTemporaries.end()); 7219 7220 // Destroy the popped expression evaluation record. 7221 Rec.Destroy(); 7222} 7223 7224/// \brief Note that the given declaration was referenced in the source code. 7225/// 7226/// This routine should be invoke whenever a given declaration is referenced 7227/// in the source code, and where that reference occurred. If this declaration 7228/// reference means that the the declaration is used (C++ [basic.def.odr]p2, 7229/// C99 6.9p3), then the declaration will be marked as used. 7230/// 7231/// \param Loc the location where the declaration was referenced. 7232/// 7233/// \param D the declaration that has been referenced by the source code. 7234void Sema::MarkDeclarationReferenced(SourceLocation Loc, Decl *D) { 7235 assert(D && "No declaration?"); 7236 7237 if (D->isUsed()) 7238 return; 7239 7240 // Mark a parameter or variable declaration "used", regardless of whether we're in a 7241 // template or not. The reason for this is that unevaluated expressions 7242 // (e.g. (void)sizeof()) constitute a use for warning purposes (-Wunused-variables and 7243 // -Wunused-parameters) 7244 if (isa<ParmVarDecl>(D) || 7245 (isa<VarDecl>(D) && D->getDeclContext()->isFunctionOrMethod())) { 7246 D->setUsed(true); 7247 return; 7248 } 7249 7250 if (!isa<VarDecl>(D) && !isa<FunctionDecl>(D)) 7251 return; 7252 7253 // Do not mark anything as "used" within a dependent context; wait for 7254 // an instantiation. 7255 if (CurContext->isDependentContext()) 7256 return; 7257 7258 switch (ExprEvalContexts.back().Context) { 7259 case Unevaluated: 7260 // We are in an expression that is not potentially evaluated; do nothing. 7261 return; 7262 7263 case PotentiallyEvaluated: 7264 // We are in a potentially-evaluated expression, so this declaration is 7265 // "used"; handle this below. 7266 break; 7267 7268 case PotentiallyPotentiallyEvaluated: 7269 // We are in an expression that may be potentially evaluated; queue this 7270 // declaration reference until we know whether the expression is 7271 // potentially evaluated. 7272 ExprEvalContexts.back().addReferencedDecl(Loc, D); 7273 return; 7274 } 7275 7276 // Note that this declaration has been used. 7277 if (CXXConstructorDecl *Constructor = dyn_cast<CXXConstructorDecl>(D)) { 7278 unsigned TypeQuals; 7279 if (Constructor->isImplicit() && Constructor->isDefaultConstructor()) { 7280 if (!Constructor->isUsed()) 7281 DefineImplicitDefaultConstructor(Loc, Constructor); 7282 } else if (Constructor->isImplicit() && 7283 Constructor->isCopyConstructor(TypeQuals)) { 7284 if (!Constructor->isUsed()) 7285 DefineImplicitCopyConstructor(Loc, Constructor, TypeQuals); 7286 } 7287 7288 MaybeMarkVirtualMembersReferenced(Loc, Constructor); 7289 } else if (CXXDestructorDecl *Destructor = dyn_cast<CXXDestructorDecl>(D)) { 7290 if (Destructor->isImplicit() && !Destructor->isUsed()) 7291 DefineImplicitDestructor(Loc, Destructor); 7292 7293 } else if (CXXMethodDecl *MethodDecl = dyn_cast<CXXMethodDecl>(D)) { 7294 if (MethodDecl->isImplicit() && MethodDecl->isOverloadedOperator() && 7295 MethodDecl->getOverloadedOperator() == OO_Equal) { 7296 if (!MethodDecl->isUsed()) 7297 DefineImplicitOverloadedAssign(Loc, MethodDecl); 7298 } 7299 } 7300 if (FunctionDecl *Function = dyn_cast<FunctionDecl>(D)) { 7301 // Implicit instantiation of function templates and member functions of 7302 // class templates. 7303 if (!Function->getBody() && Function->isImplicitlyInstantiable()) { 7304 bool AlreadyInstantiated = false; 7305 if (FunctionTemplateSpecializationInfo *SpecInfo 7306 = Function->getTemplateSpecializationInfo()) { 7307 if (SpecInfo->getPointOfInstantiation().isInvalid()) 7308 SpecInfo->setPointOfInstantiation(Loc); 7309 else if (SpecInfo->getTemplateSpecializationKind() 7310 == TSK_ImplicitInstantiation) 7311 AlreadyInstantiated = true; 7312 } else if (MemberSpecializationInfo *MSInfo 7313 = Function->getMemberSpecializationInfo()) { 7314 if (MSInfo->getPointOfInstantiation().isInvalid()) 7315 MSInfo->setPointOfInstantiation(Loc); 7316 else if (MSInfo->getTemplateSpecializationKind() 7317 == TSK_ImplicitInstantiation) 7318 AlreadyInstantiated = true; 7319 } 7320 7321 if (!AlreadyInstantiated) { 7322 if (isa<CXXRecordDecl>(Function->getDeclContext()) && 7323 cast<CXXRecordDecl>(Function->getDeclContext())->isLocalClass()) 7324 PendingLocalImplicitInstantiations.push_back(std::make_pair(Function, 7325 Loc)); 7326 else 7327 PendingImplicitInstantiations.push_back(std::make_pair(Function, 7328 Loc)); 7329 } 7330 } 7331 7332 // FIXME: keep track of references to static functions 7333 Function->setUsed(true); 7334 7335 return; 7336 } 7337 7338 if (VarDecl *Var = dyn_cast<VarDecl>(D)) { 7339 // Implicit instantiation of static data members of class templates. 7340 if (Var->isStaticDataMember() && 7341 Var->getInstantiatedFromStaticDataMember()) { 7342 MemberSpecializationInfo *MSInfo = Var->getMemberSpecializationInfo(); 7343 assert(MSInfo && "Missing member specialization information?"); 7344 if (MSInfo->getPointOfInstantiation().isInvalid() && 7345 MSInfo->getTemplateSpecializationKind()== TSK_ImplicitInstantiation) { 7346 MSInfo->setPointOfInstantiation(Loc); 7347 PendingImplicitInstantiations.push_back(std::make_pair(Var, Loc)); 7348 } 7349 } 7350 7351 // FIXME: keep track of references to static data? 7352 7353 D->setUsed(true); 7354 return; 7355 } 7356} 7357 7358/// \brief Emit a diagnostic that describes an effect on the run-time behavior 7359/// of the program being compiled. 7360/// 7361/// This routine emits the given diagnostic when the code currently being 7362/// type-checked is "potentially evaluated", meaning that there is a 7363/// possibility that the code will actually be executable. Code in sizeof() 7364/// expressions, code used only during overload resolution, etc., are not 7365/// potentially evaluated. This routine will suppress such diagnostics or, 7366/// in the absolutely nutty case of potentially potentially evaluated 7367/// expressions (C++ typeid), queue the diagnostic to potentially emit it 7368/// later. 7369/// 7370/// This routine should be used for all diagnostics that describe the run-time 7371/// behavior of a program, such as passing a non-POD value through an ellipsis. 7372/// Failure to do so will likely result in spurious diagnostics or failures 7373/// during overload resolution or within sizeof/alignof/typeof/typeid. 7374bool Sema::DiagRuntimeBehavior(SourceLocation Loc, 7375 const PartialDiagnostic &PD) { 7376 switch (ExprEvalContexts.back().Context ) { 7377 case Unevaluated: 7378 // The argument will never be evaluated, so don't complain. 7379 break; 7380 7381 case PotentiallyEvaluated: 7382 Diag(Loc, PD); 7383 return true; 7384 7385 case PotentiallyPotentiallyEvaluated: 7386 ExprEvalContexts.back().addDiagnostic(Loc, PD); 7387 break; 7388 } 7389 7390 return false; 7391} 7392 7393bool Sema::CheckCallReturnType(QualType ReturnType, SourceLocation Loc, 7394 CallExpr *CE, FunctionDecl *FD) { 7395 if (ReturnType->isVoidType() || !ReturnType->isIncompleteType()) 7396 return false; 7397 7398 PartialDiagnostic Note = 7399 FD ? PDiag(diag::note_function_with_incomplete_return_type_declared_here) 7400 << FD->getDeclName() : PDiag(); 7401 SourceLocation NoteLoc = FD ? FD->getLocation() : SourceLocation(); 7402 7403 if (RequireCompleteType(Loc, ReturnType, 7404 FD ? 7405 PDiag(diag::err_call_function_incomplete_return) 7406 << CE->getSourceRange() << FD->getDeclName() : 7407 PDiag(diag::err_call_incomplete_return) 7408 << CE->getSourceRange(), 7409 std::make_pair(NoteLoc, Note))) 7410 return true; 7411 7412 return false; 7413} 7414 7415// Diagnose the common s/=/==/ typo. Note that adding parentheses 7416// will prevent this condition from triggering, which is what we want. 7417void Sema::DiagnoseAssignmentAsCondition(Expr *E) { 7418 SourceLocation Loc; 7419 7420 unsigned diagnostic = diag::warn_condition_is_assignment; 7421 7422 if (isa<BinaryOperator>(E)) { 7423 BinaryOperator *Op = cast<BinaryOperator>(E); 7424 if (Op->getOpcode() != BinaryOperator::Assign) 7425 return; 7426 7427 // Greylist some idioms by putting them into a warning subcategory. 7428 if (ObjCMessageExpr *ME 7429 = dyn_cast<ObjCMessageExpr>(Op->getRHS()->IgnoreParenCasts())) { 7430 Selector Sel = ME->getSelector(); 7431 7432 // self = [<foo> init...] 7433 if (isSelfExpr(Op->getLHS()) 7434 && Sel.getIdentifierInfoForSlot(0)->getName().startswith("init")) 7435 diagnostic = diag::warn_condition_is_idiomatic_assignment; 7436 7437 // <foo> = [<bar> nextObject] 7438 else if (Sel.isUnarySelector() && 7439 Sel.getIdentifierInfoForSlot(0)->getName() == "nextObject") 7440 diagnostic = diag::warn_condition_is_idiomatic_assignment; 7441 } 7442 7443 Loc = Op->getOperatorLoc(); 7444 } else if (isa<CXXOperatorCallExpr>(E)) { 7445 CXXOperatorCallExpr *Op = cast<CXXOperatorCallExpr>(E); 7446 if (Op->getOperator() != OO_Equal) 7447 return; 7448 7449 Loc = Op->getOperatorLoc(); 7450 } else { 7451 // Not an assignment. 7452 return; 7453 } 7454 7455 SourceLocation Open = E->getSourceRange().getBegin(); 7456 SourceLocation Close = PP.getLocForEndOfToken(E->getSourceRange().getEnd()); 7457 7458 Diag(Loc, diagnostic) << E->getSourceRange(); 7459 Diag(Loc, diag::note_condition_assign_to_comparison) 7460 << FixItHint::CreateReplacement(Loc, "=="); 7461 Diag(Loc, diag::note_condition_assign_silence) 7462 << FixItHint::CreateInsertion(Open, "(") 7463 << FixItHint::CreateInsertion(Close, ")"); 7464} 7465 7466bool Sema::CheckBooleanCondition(Expr *&E, SourceLocation Loc) { 7467 DiagnoseAssignmentAsCondition(E); 7468 7469 if (!E->isTypeDependent()) { 7470 DefaultFunctionArrayLvalueConversion(E); 7471 7472 QualType T = E->getType(); 7473 7474 if (getLangOptions().CPlusPlus) { 7475 if (CheckCXXBooleanCondition(E)) // C++ 6.4p4 7476 return true; 7477 } else if (!T->isScalarType()) { // C99 6.8.4.1p1 7478 Diag(Loc, diag::err_typecheck_statement_requires_scalar) 7479 << T << E->getSourceRange(); 7480 return true; 7481 } 7482 } 7483 7484 return false; 7485} 7486