SemaExpr.cpp revision 4b7a834e0fecddd9eaf1f4567867c718e4eebf50
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 "clang/Analysis/AnalysisContext.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 int sentinelPos = attr->getSentinel(); 84 int nullPos = attr->getNullPos(); 85 86 // FIXME. ObjCMethodDecl and FunctionDecl need be derived from the same common 87 // base class. Then we won't be needing two versions of the same code. 88 unsigned int i = 0; 89 bool warnNotEnoughArgs = false; 90 int isMethod = 0; 91 if (ObjCMethodDecl *MD = dyn_cast<ObjCMethodDecl>(D)) { 92 // skip over named parameters. 93 ObjCMethodDecl::param_iterator P, E = MD->param_end(); 94 for (P = MD->param_begin(); (P != E && i < NumArgs); ++P) { 95 if (nullPos) 96 --nullPos; 97 else 98 ++i; 99 } 100 warnNotEnoughArgs = (P != E || i >= NumArgs); 101 isMethod = 1; 102 } else if (FunctionDecl *FD = dyn_cast<FunctionDecl>(D)) { 103 // skip over named parameters. 104 ObjCMethodDecl::param_iterator P, E = FD->param_end(); 105 for (P = FD->param_begin(); (P != E && i < NumArgs); ++P) { 106 if (nullPos) 107 --nullPos; 108 else 109 ++i; 110 } 111 warnNotEnoughArgs = (P != E || i >= NumArgs); 112 } else if (VarDecl *V = dyn_cast<VarDecl>(D)) { 113 // block or function pointer call. 114 QualType Ty = V->getType(); 115 if (Ty->isBlockPointerType() || Ty->isFunctionPointerType()) { 116 const FunctionType *FT = Ty->isFunctionPointerType() 117 ? Ty->getAs<PointerType>()->getPointeeType()->getAs<FunctionType>() 118 : Ty->getAs<BlockPointerType>()->getPointeeType()->getAs<FunctionType>(); 119 if (const FunctionProtoType *Proto = dyn_cast<FunctionProtoType>(FT)) { 120 unsigned NumArgsInProto = Proto->getNumArgs(); 121 unsigned k; 122 for (k = 0; (k != NumArgsInProto && i < NumArgs); k++) { 123 if (nullPos) 124 --nullPos; 125 else 126 ++i; 127 } 128 warnNotEnoughArgs = (k != NumArgsInProto || i >= NumArgs); 129 } 130 if (Ty->isBlockPointerType()) 131 isMethod = 2; 132 } else 133 return; 134 } else 135 return; 136 137 if (warnNotEnoughArgs) { 138 Diag(Loc, diag::warn_not_enough_argument) << D->getDeclName(); 139 Diag(D->getLocation(), diag::note_sentinel_here) << isMethod; 140 return; 141 } 142 int sentinel = i; 143 while (sentinelPos > 0 && i < NumArgs-1) { 144 --sentinelPos; 145 ++i; 146 } 147 if (sentinelPos > 0) { 148 Diag(Loc, diag::warn_not_enough_argument) << D->getDeclName(); 149 Diag(D->getLocation(), diag::note_sentinel_here) << isMethod; 150 return; 151 } 152 while (i < NumArgs-1) { 153 ++i; 154 ++sentinel; 155 } 156 Expr *sentinelExpr = Args[sentinel]; 157 if (sentinelExpr && (!isa<GNUNullExpr>(sentinelExpr) && 158 (!sentinelExpr->getType()->isPointerType() || 159 !sentinelExpr->isNullPointerConstant(Context, 160 Expr::NPC_ValueDependentIsNull)))) { 161 Diag(Loc, diag::warn_missing_sentinel) << isMethod; 162 Diag(D->getLocation(), diag::note_sentinel_here) << isMethod; 163 } 164 return; 165} 166 167SourceRange Sema::getExprRange(ExprTy *E) const { 168 Expr *Ex = (Expr *)E; 169 return Ex? Ex->getSourceRange() : SourceRange(); 170} 171 172//===----------------------------------------------------------------------===// 173// Standard Promotions and Conversions 174//===----------------------------------------------------------------------===// 175 176/// DefaultFunctionArrayConversion (C99 6.3.2.1p3, C99 6.3.2.1p4). 177void Sema::DefaultFunctionArrayConversion(Expr *&E) { 178 QualType Ty = E->getType(); 179 assert(!Ty.isNull() && "DefaultFunctionArrayConversion - missing type"); 180 181 if (Ty->isFunctionType()) 182 ImpCastExprToType(E, Context.getPointerType(Ty), 183 CastExpr::CK_FunctionToPointerDecay); 184 else if (Ty->isArrayType()) { 185 // In C90 mode, arrays only promote to pointers if the array expression is 186 // an lvalue. The relevant legalese is C90 6.2.2.1p3: "an lvalue that has 187 // type 'array of type' is converted to an expression that has type 'pointer 188 // to type'...". In C99 this was changed to: C99 6.3.2.1p3: "an expression 189 // that has type 'array of type' ...". The relevant change is "an lvalue" 190 // (C90) to "an expression" (C99). 191 // 192 // C++ 4.2p1: 193 // An lvalue or rvalue of type "array of N T" or "array of unknown bound of 194 // T" can be converted to an rvalue of type "pointer to T". 195 // 196 if (getLangOptions().C99 || getLangOptions().CPlusPlus || 197 E->isLvalue(Context) == Expr::LV_Valid) 198 ImpCastExprToType(E, Context.getArrayDecayedType(Ty), 199 CastExpr::CK_ArrayToPointerDecay); 200 } 201} 202 203void Sema::DefaultFunctionArrayLvalueConversion(Expr *&E) { 204 DefaultFunctionArrayConversion(E); 205 206 QualType Ty = E->getType(); 207 assert(!Ty.isNull() && "DefaultFunctionArrayLvalueConversion - missing type"); 208 if (!Ty->isDependentType() && Ty.hasQualifiers() && 209 (!getLangOptions().CPlusPlus || !Ty->isRecordType()) && 210 E->isLvalue(Context) == Expr::LV_Valid) { 211 // C++ [conv.lval]p1: 212 // [...] If T is a non-class type, the type of the rvalue is the 213 // cv-unqualified version of T. Otherwise, the type of the 214 // rvalue is T 215 // 216 // C99 6.3.2.1p2: 217 // If the lvalue has qualified type, the value has the unqualified 218 // version of the type of the lvalue; otherwise, the value has the 219 // type of the lvalue. 220 ImpCastExprToType(E, Ty.getUnqualifiedType(), CastExpr::CK_NoOp); 221 } 222} 223 224 225/// UsualUnaryConversions - Performs various conversions that are common to most 226/// operators (C99 6.3). The conversions of array and function types are 227/// sometimes surpressed. For example, the array->pointer conversion doesn't 228/// apply if the array is an argument to the sizeof or address (&) operators. 229/// In these instances, this routine should *not* be called. 230Expr *Sema::UsualUnaryConversions(Expr *&Expr) { 231 QualType Ty = Expr->getType(); 232 assert(!Ty.isNull() && "UsualUnaryConversions - missing type"); 233 234 // C99 6.3.1.1p2: 235 // 236 // The following may be used in an expression wherever an int or 237 // unsigned int may be used: 238 // - an object or expression with an integer type whose integer 239 // conversion rank is less than or equal to the rank of int 240 // and unsigned int. 241 // - A bit-field of type _Bool, int, signed int, or unsigned int. 242 // 243 // If an int can represent all values of the original type, the 244 // value is converted to an int; otherwise, it is converted to an 245 // unsigned int. These are called the integer promotions. All 246 // other types are unchanged by the integer promotions. 247 QualType PTy = Context.isPromotableBitField(Expr); 248 if (!PTy.isNull()) { 249 ImpCastExprToType(Expr, PTy, CastExpr::CK_IntegralCast); 250 return Expr; 251 } 252 if (Ty->isPromotableIntegerType()) { 253 QualType PT = Context.getPromotedIntegerType(Ty); 254 ImpCastExprToType(Expr, PT, CastExpr::CK_IntegralCast); 255 return Expr; 256 } 257 258 DefaultFunctionArrayLvalueConversion(Expr); 259 return Expr; 260} 261 262/// DefaultArgumentPromotion (C99 6.5.2.2p6). Used for function calls that 263/// do not have a prototype. Arguments that have type float are promoted to 264/// double. All other argument types are converted by UsualUnaryConversions(). 265void Sema::DefaultArgumentPromotion(Expr *&Expr) { 266 QualType Ty = Expr->getType(); 267 assert(!Ty.isNull() && "DefaultArgumentPromotion - missing type"); 268 269 // If this is a 'float' (CVR qualified or typedef) promote to double. 270 if (const BuiltinType *BT = Ty->getAs<BuiltinType>()) 271 if (BT->getKind() == BuiltinType::Float) 272 return ImpCastExprToType(Expr, Context.DoubleTy, 273 CastExpr::CK_FloatingCast); 274 275 UsualUnaryConversions(Expr); 276} 277 278/// DefaultVariadicArgumentPromotion - Like DefaultArgumentPromotion, but 279/// will warn if the resulting type is not a POD type, and rejects ObjC 280/// interfaces passed by value. This returns true if the argument type is 281/// completely illegal. 282bool Sema::DefaultVariadicArgumentPromotion(Expr *&Expr, VariadicCallType CT) { 283 DefaultArgumentPromotion(Expr); 284 285 if (Expr->getType()->isObjCInterfaceType() && 286 DiagRuntimeBehavior(Expr->getLocStart(), 287 PDiag(diag::err_cannot_pass_objc_interface_to_vararg) 288 << Expr->getType() << CT)) 289 return true; 290 291 if (!Expr->getType()->isPODType() && 292 DiagRuntimeBehavior(Expr->getLocStart(), 293 PDiag(diag::warn_cannot_pass_non_pod_arg_to_vararg) 294 << Expr->getType() << CT)) 295 return true; 296 297 return false; 298} 299 300 301/// UsualArithmeticConversions - Performs various conversions that are common to 302/// binary operators (C99 6.3.1.8). If both operands aren't arithmetic, this 303/// routine returns the first non-arithmetic type found. The client is 304/// responsible for emitting appropriate error diagnostics. 305/// FIXME: verify the conversion rules for "complex int" are consistent with 306/// GCC. 307QualType Sema::UsualArithmeticConversions(Expr *&lhsExpr, Expr *&rhsExpr, 308 bool isCompAssign) { 309 if (!isCompAssign) 310 UsualUnaryConversions(lhsExpr); 311 312 UsualUnaryConversions(rhsExpr); 313 314 // For conversion purposes, we ignore any qualifiers. 315 // For example, "const float" and "float" are equivalent. 316 QualType lhs = 317 Context.getCanonicalType(lhsExpr->getType()).getUnqualifiedType(); 318 QualType rhs = 319 Context.getCanonicalType(rhsExpr->getType()).getUnqualifiedType(); 320 321 // If both types are identical, no conversion is needed. 322 if (lhs == rhs) 323 return lhs; 324 325 // If either side is a non-arithmetic type (e.g. a pointer), we are done. 326 // The caller can deal with this (e.g. pointer + int). 327 if (!lhs->isArithmeticType() || !rhs->isArithmeticType()) 328 return lhs; 329 330 // Perform bitfield promotions. 331 QualType LHSBitfieldPromoteTy = Context.isPromotableBitField(lhsExpr); 332 if (!LHSBitfieldPromoteTy.isNull()) 333 lhs = LHSBitfieldPromoteTy; 334 QualType RHSBitfieldPromoteTy = Context.isPromotableBitField(rhsExpr); 335 if (!RHSBitfieldPromoteTy.isNull()) 336 rhs = RHSBitfieldPromoteTy; 337 338 QualType destType = Context.UsualArithmeticConversionsType(lhs, rhs); 339 if (!isCompAssign) 340 ImpCastExprToType(lhsExpr, destType, CastExpr::CK_Unknown); 341 ImpCastExprToType(rhsExpr, destType, CastExpr::CK_Unknown); 342 return destType; 343} 344 345//===----------------------------------------------------------------------===// 346// Semantic Analysis for various Expression Types 347//===----------------------------------------------------------------------===// 348 349 350/// ActOnStringLiteral - The specified tokens were lexed as pasted string 351/// fragments (e.g. "foo" "bar" L"baz"). The result string has to handle string 352/// concatenation ([C99 5.1.1.2, translation phase #6]), so it may come from 353/// multiple tokens. However, the common case is that StringToks points to one 354/// string. 355/// 356Action::OwningExprResult 357Sema::ActOnStringLiteral(const Token *StringToks, unsigned NumStringToks) { 358 assert(NumStringToks && "Must have at least one string!"); 359 360 StringLiteralParser Literal(StringToks, NumStringToks, PP); 361 if (Literal.hadError) 362 return ExprError(); 363 364 llvm::SmallVector<SourceLocation, 4> StringTokLocs; 365 for (unsigned i = 0; i != NumStringToks; ++i) 366 StringTokLocs.push_back(StringToks[i].getLocation()); 367 368 QualType StrTy = Context.CharTy; 369 if (Literal.AnyWide) StrTy = Context.getWCharType(); 370 if (Literal.Pascal) StrTy = Context.UnsignedCharTy; 371 372 // A C++ string literal has a const-qualified element type (C++ 2.13.4p1). 373 if (getLangOptions().CPlusPlus || getLangOptions().ConstStrings ) 374 StrTy.addConst(); 375 376 // Get an array type for the string, according to C99 6.4.5. This includes 377 // the nul terminator character as well as the string length for pascal 378 // strings. 379 StrTy = Context.getConstantArrayType(StrTy, 380 llvm::APInt(32, Literal.GetNumStringChars()+1), 381 ArrayType::Normal, 0); 382 383 // Pass &StringTokLocs[0], StringTokLocs.size() to factory! 384 return Owned(StringLiteral::Create(Context, Literal.GetString(), 385 Literal.GetStringLength(), 386 Literal.AnyWide, StrTy, 387 &StringTokLocs[0], 388 StringTokLocs.size())); 389} 390 391/// ShouldSnapshotBlockValueReference - Return true if a reference inside of 392/// CurBlock to VD should cause it to be snapshotted (as we do for auto 393/// variables defined outside the block) or false if this is not needed (e.g. 394/// for values inside the block or for globals). 395/// 396/// This also keeps the 'hasBlockDeclRefExprs' in the BlockScopeInfo records 397/// up-to-date. 398/// 399static bool ShouldSnapshotBlockValueReference(Sema &S, BlockScopeInfo *CurBlock, 400 ValueDecl *VD) { 401 // If the value is defined inside the block, we couldn't snapshot it even if 402 // we wanted to. 403 if (CurBlock->TheDecl == VD->getDeclContext()) 404 return false; 405 406 // If this is an enum constant or function, it is constant, don't snapshot. 407 if (isa<EnumConstantDecl>(VD) || isa<FunctionDecl>(VD)) 408 return false; 409 410 // If this is a reference to an extern, static, or global variable, no need to 411 // snapshot it. 412 // FIXME: What about 'const' variables in C++? 413 if (const VarDecl *Var = dyn_cast<VarDecl>(VD)) 414 if (!Var->hasLocalStorage()) 415 return false; 416 417 // Blocks that have these can't be constant. 418 CurBlock->hasBlockDeclRefExprs = true; 419 420 // If we have nested blocks, the decl may be declared in an outer block (in 421 // which case that outer block doesn't get "hasBlockDeclRefExprs") or it may 422 // be defined outside all of the current blocks (in which case the blocks do 423 // all get the bit). Walk the nesting chain. 424 for (unsigned I = S.FunctionScopes.size() - 1; I; --I) { 425 BlockScopeInfo *NextBlock = dyn_cast<BlockScopeInfo>(S.FunctionScopes[I]); 426 427 if (!NextBlock) 428 continue; 429 430 // If we found the defining block for the variable, don't mark the block as 431 // having a reference outside it. 432 if (NextBlock->TheDecl == VD->getDeclContext()) 433 break; 434 435 // Otherwise, the DeclRef from the inner block causes the outer one to need 436 // a snapshot as well. 437 NextBlock->hasBlockDeclRefExprs = true; 438 } 439 440 return true; 441} 442 443 444 445/// BuildDeclRefExpr - Build a DeclRefExpr. 446Sema::OwningExprResult 447Sema::BuildDeclRefExpr(ValueDecl *D, QualType Ty, SourceLocation Loc, 448 const CXXScopeSpec *SS) { 449 if (Context.getCanonicalType(Ty) == Context.UndeducedAutoTy) { 450 Diag(Loc, 451 diag::err_auto_variable_cannot_appear_in_own_initializer) 452 << D->getDeclName(); 453 return ExprError(); 454 } 455 456 if (const VarDecl *VD = dyn_cast<VarDecl>(D)) { 457 if (const CXXMethodDecl *MD = dyn_cast<CXXMethodDecl>(CurContext)) { 458 if (const FunctionDecl *FD = MD->getParent()->isLocalClass()) { 459 if (VD->hasLocalStorage() && VD->getDeclContext() != CurContext) { 460 Diag(Loc, diag::err_reference_to_local_var_in_enclosing_function) 461 << D->getIdentifier() << FD->getDeclName(); 462 Diag(D->getLocation(), diag::note_local_variable_declared_here) 463 << D->getIdentifier(); 464 return ExprError(); 465 } 466 } 467 } 468 } 469 470 MarkDeclarationReferenced(Loc, D); 471 472 return Owned(DeclRefExpr::Create(Context, 473 SS? (NestedNameSpecifier *)SS->getScopeRep() : 0, 474 SS? SS->getRange() : SourceRange(), 475 D, Loc, Ty)); 476} 477 478/// getObjectForAnonymousRecordDecl - Retrieve the (unnamed) field or 479/// variable corresponding to the anonymous union or struct whose type 480/// is Record. 481static Decl *getObjectForAnonymousRecordDecl(ASTContext &Context, 482 RecordDecl *Record) { 483 assert(Record->isAnonymousStructOrUnion() && 484 "Record must be an anonymous struct or union!"); 485 486 // FIXME: Once Decls are directly linked together, this will be an O(1) 487 // operation rather than a slow walk through DeclContext's vector (which 488 // itself will be eliminated). DeclGroups might make this even better. 489 DeclContext *Ctx = Record->getDeclContext(); 490 for (DeclContext::decl_iterator D = Ctx->decls_begin(), 491 DEnd = Ctx->decls_end(); 492 D != DEnd; ++D) { 493 if (*D == Record) { 494 // The object for the anonymous struct/union directly 495 // follows its type in the list of declarations. 496 ++D; 497 assert(D != DEnd && "Missing object for anonymous record"); 498 assert(!cast<NamedDecl>(*D)->getDeclName() && "Decl should be unnamed"); 499 return *D; 500 } 501 } 502 503 assert(false && "Missing object for anonymous record"); 504 return 0; 505} 506 507/// \brief Given a field that represents a member of an anonymous 508/// struct/union, build the path from that field's context to the 509/// actual member. 510/// 511/// Construct the sequence of field member references we'll have to 512/// perform to get to the field in the anonymous union/struct. The 513/// list of members is built from the field outward, so traverse it 514/// backwards to go from an object in the current context to the field 515/// we found. 516/// 517/// \returns The variable from which the field access should begin, 518/// for an anonymous struct/union that is not a member of another 519/// class. Otherwise, returns NULL. 520VarDecl *Sema::BuildAnonymousStructUnionMemberPath(FieldDecl *Field, 521 llvm::SmallVectorImpl<FieldDecl *> &Path) { 522 assert(Field->getDeclContext()->isRecord() && 523 cast<RecordDecl>(Field->getDeclContext())->isAnonymousStructOrUnion() 524 && "Field must be stored inside an anonymous struct or union"); 525 526 Path.push_back(Field); 527 VarDecl *BaseObject = 0; 528 DeclContext *Ctx = Field->getDeclContext(); 529 do { 530 RecordDecl *Record = cast<RecordDecl>(Ctx); 531 Decl *AnonObject = getObjectForAnonymousRecordDecl(Context, Record); 532 if (FieldDecl *AnonField = dyn_cast<FieldDecl>(AnonObject)) 533 Path.push_back(AnonField); 534 else { 535 BaseObject = cast<VarDecl>(AnonObject); 536 break; 537 } 538 Ctx = Ctx->getParent(); 539 } while (Ctx->isRecord() && 540 cast<RecordDecl>(Ctx)->isAnonymousStructOrUnion()); 541 542 return BaseObject; 543} 544 545Sema::OwningExprResult 546Sema::BuildAnonymousStructUnionMemberReference(SourceLocation Loc, 547 FieldDecl *Field, 548 Expr *BaseObjectExpr, 549 SourceLocation OpLoc) { 550 llvm::SmallVector<FieldDecl *, 4> AnonFields; 551 VarDecl *BaseObject = BuildAnonymousStructUnionMemberPath(Field, 552 AnonFields); 553 554 // Build the expression that refers to the base object, from 555 // which we will build a sequence of member references to each 556 // of the anonymous union objects and, eventually, the field we 557 // found via name lookup. 558 bool BaseObjectIsPointer = false; 559 Qualifiers BaseQuals; 560 if (BaseObject) { 561 // BaseObject is an anonymous struct/union variable (and is, 562 // therefore, not part of another non-anonymous record). 563 if (BaseObjectExpr) BaseObjectExpr->Destroy(Context); 564 MarkDeclarationReferenced(Loc, BaseObject); 565 BaseObjectExpr = new (Context) DeclRefExpr(BaseObject,BaseObject->getType(), 566 SourceLocation()); 567 BaseQuals 568 = Context.getCanonicalType(BaseObject->getType()).getQualifiers(); 569 } else if (BaseObjectExpr) { 570 // The caller provided the base object expression. Determine 571 // whether its a pointer and whether it adds any qualifiers to the 572 // anonymous struct/union fields we're looking into. 573 QualType ObjectType = BaseObjectExpr->getType(); 574 if (const PointerType *ObjectPtr = ObjectType->getAs<PointerType>()) { 575 BaseObjectIsPointer = true; 576 ObjectType = ObjectPtr->getPointeeType(); 577 } 578 BaseQuals 579 = Context.getCanonicalType(ObjectType).getQualifiers(); 580 } else { 581 // We've found a member of an anonymous struct/union that is 582 // inside a non-anonymous struct/union, so in a well-formed 583 // program our base object expression is "this". 584 if (CXXMethodDecl *MD = dyn_cast<CXXMethodDecl>(CurContext)) { 585 if (!MD->isStatic()) { 586 QualType AnonFieldType 587 = Context.getTagDeclType( 588 cast<RecordDecl>(AnonFields.back()->getDeclContext())); 589 QualType ThisType = Context.getTagDeclType(MD->getParent()); 590 if ((Context.getCanonicalType(AnonFieldType) 591 == Context.getCanonicalType(ThisType)) || 592 IsDerivedFrom(ThisType, AnonFieldType)) { 593 // Our base object expression is "this". 594 BaseObjectExpr = new (Context) CXXThisExpr(Loc, 595 MD->getThisType(Context), 596 /*isImplicit=*/true); 597 BaseObjectIsPointer = true; 598 } 599 } else { 600 return ExprError(Diag(Loc,diag::err_invalid_member_use_in_static_method) 601 << Field->getDeclName()); 602 } 603 BaseQuals = Qualifiers::fromCVRMask(MD->getTypeQualifiers()); 604 } 605 606 if (!BaseObjectExpr) 607 return ExprError(Diag(Loc, diag::err_invalid_non_static_member_use) 608 << Field->getDeclName()); 609 } 610 611 // Build the implicit member references to the field of the 612 // anonymous struct/union. 613 Expr *Result = BaseObjectExpr; 614 Qualifiers ResultQuals = BaseQuals; 615 for (llvm::SmallVector<FieldDecl *, 4>::reverse_iterator 616 FI = AnonFields.rbegin(), FIEnd = AnonFields.rend(); 617 FI != FIEnd; ++FI) { 618 QualType MemberType = (*FI)->getType(); 619 Qualifiers MemberTypeQuals = 620 Context.getCanonicalType(MemberType).getQualifiers(); 621 622 // CVR attributes from the base are picked up by members, 623 // except that 'mutable' members don't pick up 'const'. 624 if ((*FI)->isMutable()) 625 ResultQuals.removeConst(); 626 627 // GC attributes are never picked up by members. 628 ResultQuals.removeObjCGCAttr(); 629 630 // TR 18037 does not allow fields to be declared with address spaces. 631 assert(!MemberTypeQuals.hasAddressSpace()); 632 633 Qualifiers NewQuals = ResultQuals + MemberTypeQuals; 634 if (NewQuals != MemberTypeQuals) 635 MemberType = Context.getQualifiedType(MemberType, NewQuals); 636 637 MarkDeclarationReferenced(Loc, *FI); 638 PerformObjectMemberConversion(Result, /*FIXME:Qualifier=*/0, *FI); 639 // FIXME: Might this end up being a qualified name? 640 Result = new (Context) MemberExpr(Result, BaseObjectIsPointer, *FI, 641 OpLoc, MemberType); 642 BaseObjectIsPointer = false; 643 ResultQuals = NewQuals; 644 } 645 646 return Owned(Result); 647} 648 649/// Decomposes the given name into a DeclarationName, its location, and 650/// possibly a list of template arguments. 651/// 652/// If this produces template arguments, it is permitted to call 653/// DecomposeTemplateName. 654/// 655/// This actually loses a lot of source location information for 656/// non-standard name kinds; we should consider preserving that in 657/// some way. 658static void DecomposeUnqualifiedId(Sema &SemaRef, 659 const UnqualifiedId &Id, 660 TemplateArgumentListInfo &Buffer, 661 DeclarationName &Name, 662 SourceLocation &NameLoc, 663 const TemplateArgumentListInfo *&TemplateArgs) { 664 if (Id.getKind() == UnqualifiedId::IK_TemplateId) { 665 Buffer.setLAngleLoc(Id.TemplateId->LAngleLoc); 666 Buffer.setRAngleLoc(Id.TemplateId->RAngleLoc); 667 668 ASTTemplateArgsPtr TemplateArgsPtr(SemaRef, 669 Id.TemplateId->getTemplateArgs(), 670 Id.TemplateId->NumArgs); 671 SemaRef.translateTemplateArguments(TemplateArgsPtr, Buffer); 672 TemplateArgsPtr.release(); 673 674 TemplateName TName = 675 Sema::TemplateTy::make(Id.TemplateId->Template).getAsVal<TemplateName>(); 676 677 Name = SemaRef.Context.getNameForTemplate(TName); 678 NameLoc = Id.TemplateId->TemplateNameLoc; 679 TemplateArgs = &Buffer; 680 } else { 681 Name = SemaRef.GetNameFromUnqualifiedId(Id); 682 NameLoc = Id.StartLocation; 683 TemplateArgs = 0; 684 } 685} 686 687/// Decompose the given template name into a list of lookup results. 688/// 689/// The unqualified ID must name a non-dependent template, which can 690/// be more easily tested by checking whether DecomposeUnqualifiedId 691/// found template arguments. 692static void DecomposeTemplateName(LookupResult &R, const UnqualifiedId &Id) { 693 assert(Id.getKind() == UnqualifiedId::IK_TemplateId); 694 TemplateName TName = 695 Sema::TemplateTy::make(Id.TemplateId->Template).getAsVal<TemplateName>(); 696 697 if (TemplateDecl *TD = TName.getAsTemplateDecl()) 698 R.addDecl(TD); 699 else if (OverloadedTemplateStorage *OT = TName.getAsOverloadedTemplate()) 700 for (OverloadedTemplateStorage::iterator I = OT->begin(), E = OT->end(); 701 I != E; ++I) 702 R.addDecl(*I); 703 704 R.resolveKind(); 705} 706 707/// Determines whether the given record is "fully-formed" at the given 708/// location, i.e. whether a qualified lookup into it is assured of 709/// getting consistent results already. 710static bool IsFullyFormedScope(Sema &SemaRef, CXXRecordDecl *Record) { 711 if (!Record->hasDefinition()) 712 return false; 713 714 for (CXXRecordDecl::base_class_iterator I = Record->bases_begin(), 715 E = Record->bases_end(); I != E; ++I) { 716 CanQualType BaseT = SemaRef.Context.getCanonicalType((*I).getType()); 717 CanQual<RecordType> BaseRT = BaseT->getAs<RecordType>(); 718 if (!BaseRT) return false; 719 720 CXXRecordDecl *BaseRecord = cast<CXXRecordDecl>(BaseRT->getDecl()); 721 if (!BaseRecord->hasDefinition() || 722 !IsFullyFormedScope(SemaRef, BaseRecord)) 723 return false; 724 } 725 726 return true; 727} 728 729/// Determines whether we can lookup this id-expression now or whether 730/// we have to wait until template instantiation is complete. 731static bool IsDependentIdExpression(Sema &SemaRef, const CXXScopeSpec &SS) { 732 DeclContext *DC = SemaRef.computeDeclContext(SS, false); 733 734 // If the qualifier scope isn't computable, it's definitely dependent. 735 if (!DC) return true; 736 737 // If the qualifier scope doesn't name a record, we can always look into it. 738 if (!isa<CXXRecordDecl>(DC)) return false; 739 740 // We can't look into record types unless they're fully-formed. 741 if (!IsFullyFormedScope(SemaRef, cast<CXXRecordDecl>(DC))) return true; 742 743 return false; 744} 745 746/// Determines if the given class is provably not derived from all of 747/// the prospective base classes. 748static bool IsProvablyNotDerivedFrom(Sema &SemaRef, 749 CXXRecordDecl *Record, 750 const llvm::SmallPtrSet<CXXRecordDecl*, 4> &Bases) { 751 if (Bases.count(Record->getCanonicalDecl())) 752 return false; 753 754 RecordDecl *RD = Record->getDefinition(); 755 if (!RD) return false; 756 Record = cast<CXXRecordDecl>(RD); 757 758 for (CXXRecordDecl::base_class_iterator I = Record->bases_begin(), 759 E = Record->bases_end(); I != E; ++I) { 760 CanQualType BaseT = SemaRef.Context.getCanonicalType((*I).getType()); 761 CanQual<RecordType> BaseRT = BaseT->getAs<RecordType>(); 762 if (!BaseRT) return false; 763 764 CXXRecordDecl *BaseRecord = cast<CXXRecordDecl>(BaseRT->getDecl()); 765 if (!IsProvablyNotDerivedFrom(SemaRef, BaseRecord, Bases)) 766 return false; 767 } 768 769 return true; 770} 771 772/// Determines if this is an instance member of a class. 773static bool IsInstanceMember(NamedDecl *D) { 774 assert(D->isCXXClassMember() && 775 "checking whether non-member is instance member"); 776 777 if (isa<FieldDecl>(D)) return true; 778 779 if (isa<CXXMethodDecl>(D)) 780 return !cast<CXXMethodDecl>(D)->isStatic(); 781 782 if (isa<FunctionTemplateDecl>(D)) { 783 D = cast<FunctionTemplateDecl>(D)->getTemplatedDecl(); 784 return !cast<CXXMethodDecl>(D)->isStatic(); 785 } 786 787 return false; 788} 789 790enum IMAKind { 791 /// The reference is definitely not an instance member access. 792 IMA_Static, 793 794 /// The reference may be an implicit instance member access. 795 IMA_Mixed, 796 797 /// The reference may be to an instance member, but it is invalid if 798 /// so, because the context is not an instance method. 799 IMA_Mixed_StaticContext, 800 801 /// The reference may be to an instance member, but it is invalid if 802 /// so, because the context is from an unrelated class. 803 IMA_Mixed_Unrelated, 804 805 /// The reference is definitely an implicit instance member access. 806 IMA_Instance, 807 808 /// The reference may be to an unresolved using declaration. 809 IMA_Unresolved, 810 811 /// The reference may be to an unresolved using declaration and the 812 /// context is not an instance method. 813 IMA_Unresolved_StaticContext, 814 815 /// The reference is to a member of an anonymous structure in a 816 /// non-class context. 817 IMA_AnonymousMember, 818 819 /// All possible referrents are instance members and the current 820 /// context is not an instance method. 821 IMA_Error_StaticContext, 822 823 /// All possible referrents are instance members of an unrelated 824 /// class. 825 IMA_Error_Unrelated 826}; 827 828/// The given lookup names class member(s) and is not being used for 829/// an address-of-member expression. Classify the type of access 830/// according to whether it's possible that this reference names an 831/// instance member. This is best-effort; it is okay to 832/// conservatively answer "yes", in which case some errors will simply 833/// not be caught until template-instantiation. 834static IMAKind ClassifyImplicitMemberAccess(Sema &SemaRef, 835 const LookupResult &R) { 836 assert(!R.empty() && (*R.begin())->isCXXClassMember()); 837 838 bool isStaticContext = 839 (!isa<CXXMethodDecl>(SemaRef.CurContext) || 840 cast<CXXMethodDecl>(SemaRef.CurContext)->isStatic()); 841 842 if (R.isUnresolvableResult()) 843 return isStaticContext ? IMA_Unresolved_StaticContext : IMA_Unresolved; 844 845 // Collect all the declaring classes of instance members we find. 846 bool hasNonInstance = false; 847 llvm::SmallPtrSet<CXXRecordDecl*, 4> Classes; 848 for (LookupResult::iterator I = R.begin(), E = R.end(); I != E; ++I) { 849 NamedDecl *D = (*I)->getUnderlyingDecl(); 850 if (IsInstanceMember(D)) { 851 CXXRecordDecl *R = cast<CXXRecordDecl>(D->getDeclContext()); 852 853 // If this is a member of an anonymous record, move out to the 854 // innermost non-anonymous struct or union. If there isn't one, 855 // that's a special case. 856 while (R->isAnonymousStructOrUnion()) { 857 R = dyn_cast<CXXRecordDecl>(R->getParent()); 858 if (!R) return IMA_AnonymousMember; 859 } 860 Classes.insert(R->getCanonicalDecl()); 861 } 862 else 863 hasNonInstance = true; 864 } 865 866 // If we didn't find any instance members, it can't be an implicit 867 // member reference. 868 if (Classes.empty()) 869 return IMA_Static; 870 871 // If the current context is not an instance method, it can't be 872 // an implicit member reference. 873 if (isStaticContext) 874 return (hasNonInstance ? IMA_Mixed_StaticContext : IMA_Error_StaticContext); 875 876 // If we can prove that the current context is unrelated to all the 877 // declaring classes, it can't be an implicit member reference (in 878 // which case it's an error if any of those members are selected). 879 if (IsProvablyNotDerivedFrom(SemaRef, 880 cast<CXXMethodDecl>(SemaRef.CurContext)->getParent(), 881 Classes)) 882 return (hasNonInstance ? IMA_Mixed_Unrelated : IMA_Error_Unrelated); 883 884 return (hasNonInstance ? IMA_Mixed : IMA_Instance); 885} 886 887/// Diagnose a reference to a field with no object available. 888static void DiagnoseInstanceReference(Sema &SemaRef, 889 const CXXScopeSpec &SS, 890 const LookupResult &R) { 891 SourceLocation Loc = R.getNameLoc(); 892 SourceRange Range(Loc); 893 if (SS.isSet()) Range.setBegin(SS.getRange().getBegin()); 894 895 if (R.getAsSingle<FieldDecl>()) { 896 if (CXXMethodDecl *MD = dyn_cast<CXXMethodDecl>(SemaRef.CurContext)) { 897 if (MD->isStatic()) { 898 // "invalid use of member 'x' in static member function" 899 SemaRef.Diag(Loc, diag::err_invalid_member_use_in_static_method) 900 << Range << R.getLookupName(); 901 return; 902 } 903 } 904 905 SemaRef.Diag(Loc, diag::err_invalid_non_static_member_use) 906 << R.getLookupName() << Range; 907 return; 908 } 909 910 SemaRef.Diag(Loc, diag::err_member_call_without_object) << Range; 911} 912 913/// Diagnose an empty lookup. 914/// 915/// \return false if new lookup candidates were found 916bool Sema::DiagnoseEmptyLookup(Scope *S, const CXXScopeSpec &SS, 917 LookupResult &R) { 918 DeclarationName Name = R.getLookupName(); 919 920 unsigned diagnostic = diag::err_undeclared_var_use; 921 unsigned diagnostic_suggest = diag::err_undeclared_var_use_suggest; 922 if (Name.getNameKind() == DeclarationName::CXXOperatorName || 923 Name.getNameKind() == DeclarationName::CXXLiteralOperatorName || 924 Name.getNameKind() == DeclarationName::CXXConversionFunctionName) { 925 diagnostic = diag::err_undeclared_use; 926 diagnostic_suggest = diag::err_undeclared_use_suggest; 927 } 928 929 // If the original lookup was an unqualified lookup, fake an 930 // unqualified lookup. This is useful when (for example) the 931 // original lookup would not have found something because it was a 932 // dependent name. 933 for (DeclContext *DC = SS.isEmpty()? CurContext : 0; 934 DC; DC = DC->getParent()) { 935 if (isa<CXXRecordDecl>(DC)) { 936 LookupQualifiedName(R, DC); 937 938 if (!R.empty()) { 939 // Don't give errors about ambiguities in this lookup. 940 R.suppressDiagnostics(); 941 942 CXXMethodDecl *CurMethod = dyn_cast<CXXMethodDecl>(CurContext); 943 bool isInstance = CurMethod && 944 CurMethod->isInstance() && 945 DC == CurMethod->getParent(); 946 947 // Give a code modification hint to insert 'this->'. 948 // TODO: fixit for inserting 'Base<T>::' in the other cases. 949 // Actually quite difficult! 950 if (isInstance) 951 Diag(R.getNameLoc(), diagnostic) << Name 952 << CodeModificationHint::CreateInsertion(R.getNameLoc(), 953 "this->"); 954 else 955 Diag(R.getNameLoc(), diagnostic) << Name; 956 957 // Do we really want to note all of these? 958 for (LookupResult::iterator I = R.begin(), E = R.end(); I != E; ++I) 959 Diag((*I)->getLocation(), diag::note_dependent_var_use); 960 961 // Tell the callee to try to recover. 962 return false; 963 } 964 } 965 } 966 967 // We didn't find anything, so try to correct for a typo. 968 if (S && CorrectTypo(R, S, &SS)) { 969 if (isa<ValueDecl>(*R.begin()) || isa<FunctionTemplateDecl>(*R.begin())) { 970 if (SS.isEmpty()) 971 Diag(R.getNameLoc(), diagnostic_suggest) << Name << R.getLookupName() 972 << CodeModificationHint::CreateReplacement(R.getNameLoc(), 973 R.getLookupName().getAsString()); 974 else 975 Diag(R.getNameLoc(), diag::err_no_member_suggest) 976 << Name << computeDeclContext(SS, false) << R.getLookupName() 977 << SS.getRange() 978 << CodeModificationHint::CreateReplacement(R.getNameLoc(), 979 R.getLookupName().getAsString()); 980 if (NamedDecl *ND = R.getAsSingle<NamedDecl>()) 981 Diag(ND->getLocation(), diag::note_previous_decl) 982 << ND->getDeclName(); 983 984 // Tell the callee to try to recover. 985 return false; 986 } 987 988 if (isa<TypeDecl>(*R.begin()) || isa<ObjCInterfaceDecl>(*R.begin())) { 989 // FIXME: If we ended up with a typo for a type name or 990 // Objective-C class name, we're in trouble because the parser 991 // is in the wrong place to recover. Suggest the typo 992 // correction, but don't make it a fix-it since we're not going 993 // to recover well anyway. 994 if (SS.isEmpty()) 995 Diag(R.getNameLoc(), diagnostic_suggest) << Name << R.getLookupName(); 996 else 997 Diag(R.getNameLoc(), diag::err_no_member_suggest) 998 << Name << computeDeclContext(SS, false) << R.getLookupName() 999 << SS.getRange(); 1000 1001 // Don't try to recover; it won't work. 1002 return true; 1003 } 1004 1005 R.clear(); 1006 } 1007 1008 // Emit a special diagnostic for failed member lookups. 1009 // FIXME: computing the declaration context might fail here (?) 1010 if (!SS.isEmpty()) { 1011 Diag(R.getNameLoc(), diag::err_no_member) 1012 << Name << computeDeclContext(SS, false) 1013 << SS.getRange(); 1014 return true; 1015 } 1016 1017 // Give up, we can't recover. 1018 Diag(R.getNameLoc(), diagnostic) << Name; 1019 return true; 1020} 1021 1022Sema::OwningExprResult Sema::ActOnIdExpression(Scope *S, 1023 const CXXScopeSpec &SS, 1024 UnqualifiedId &Id, 1025 bool HasTrailingLParen, 1026 bool isAddressOfOperand) { 1027 assert(!(isAddressOfOperand && HasTrailingLParen) && 1028 "cannot be direct & operand and have a trailing lparen"); 1029 1030 if (SS.isInvalid()) 1031 return ExprError(); 1032 1033 TemplateArgumentListInfo TemplateArgsBuffer; 1034 1035 // Decompose the UnqualifiedId into the following data. 1036 DeclarationName Name; 1037 SourceLocation NameLoc; 1038 const TemplateArgumentListInfo *TemplateArgs; 1039 DecomposeUnqualifiedId(*this, Id, TemplateArgsBuffer, 1040 Name, NameLoc, TemplateArgs); 1041 1042 IdentifierInfo *II = Name.getAsIdentifierInfo(); 1043 1044 // C++ [temp.dep.expr]p3: 1045 // An id-expression is type-dependent if it contains: 1046 // -- an identifier that was declared with a dependent type, 1047 // (note: handled after lookup) 1048 // -- a template-id that is dependent, 1049 // (note: handled in BuildTemplateIdExpr) 1050 // -- a conversion-function-id that specifies a dependent type, 1051 // -- a nested-name-specifier that contains a class-name that 1052 // names a dependent type. 1053 // Determine whether this is a member of an unknown specialization; 1054 // we need to handle these differently. 1055 if ((Name.getNameKind() == DeclarationName::CXXConversionFunctionName && 1056 Name.getCXXNameType()->isDependentType()) || 1057 (SS.isSet() && IsDependentIdExpression(*this, SS))) { 1058 return ActOnDependentIdExpression(SS, Name, NameLoc, 1059 isAddressOfOperand, 1060 TemplateArgs); 1061 } 1062 1063 // Perform the required lookup. 1064 LookupResult R(*this, Name, NameLoc, LookupOrdinaryName); 1065 if (TemplateArgs) { 1066 // Just re-use the lookup done by isTemplateName. 1067 DecomposeTemplateName(R, Id); 1068 } else { 1069 bool IvarLookupFollowUp = (!SS.isSet() && II && getCurMethodDecl()); 1070 LookupParsedName(R, S, &SS, !IvarLookupFollowUp); 1071 1072 // If this reference is in an Objective-C method, then we need to do 1073 // some special Objective-C lookup, too. 1074 if (IvarLookupFollowUp) { 1075 OwningExprResult E(LookupInObjCMethod(R, S, II, true)); 1076 if (E.isInvalid()) 1077 return ExprError(); 1078 1079 Expr *Ex = E.takeAs<Expr>(); 1080 if (Ex) return Owned(Ex); 1081 } 1082 } 1083 1084 if (R.isAmbiguous()) 1085 return ExprError(); 1086 1087 // Determine whether this name might be a candidate for 1088 // argument-dependent lookup. 1089 bool ADL = UseArgumentDependentLookup(SS, R, HasTrailingLParen); 1090 1091 if (R.empty() && !ADL) { 1092 // Otherwise, this could be an implicitly declared function reference (legal 1093 // in C90, extension in C99, forbidden in C++). 1094 if (HasTrailingLParen && II && !getLangOptions().CPlusPlus) { 1095 NamedDecl *D = ImplicitlyDefineFunction(NameLoc, *II, S); 1096 if (D) R.addDecl(D); 1097 } 1098 1099 // If this name wasn't predeclared and if this is not a function 1100 // call, diagnose the problem. 1101 if (R.empty()) { 1102 if (DiagnoseEmptyLookup(S, SS, R)) 1103 return ExprError(); 1104 1105 assert(!R.empty() && 1106 "DiagnoseEmptyLookup returned false but added no results"); 1107 1108 // If we found an Objective-C instance variable, let 1109 // LookupInObjCMethod build the appropriate expression to 1110 // reference the ivar. 1111 if (ObjCIvarDecl *Ivar = R.getAsSingle<ObjCIvarDecl>()) { 1112 R.clear(); 1113 OwningExprResult E(LookupInObjCMethod(R, S, Ivar->getIdentifier())); 1114 assert(E.isInvalid() || E.get()); 1115 return move(E); 1116 } 1117 } 1118 } 1119 1120 // This is guaranteed from this point on. 1121 assert(!R.empty() || ADL); 1122 1123 if (VarDecl *Var = R.getAsSingle<VarDecl>()) { 1124 // Warn about constructs like: 1125 // if (void *X = foo()) { ... } else { X }. 1126 // In the else block, the pointer is always false. 1127 1128 if (Var->isDeclaredInCondition() && Var->getType()->isScalarType()) { 1129 Scope *CheckS = S; 1130 while (CheckS && CheckS->getControlParent()) { 1131 if (CheckS->isWithinElse() && 1132 CheckS->getControlParent()->isDeclScope(DeclPtrTy::make(Var))) { 1133 ExprError(Diag(NameLoc, diag::warn_value_always_zero) 1134 << Var->getDeclName() 1135 << (Var->getType()->isPointerType()? 2 : 1136 Var->getType()->isBooleanType()? 1 : 0)); 1137 break; 1138 } 1139 1140 // Move to the parent of this scope. 1141 CheckS = CheckS->getParent(); 1142 } 1143 } 1144 } else if (FunctionDecl *Func = R.getAsSingle<FunctionDecl>()) { 1145 if (!getLangOptions().CPlusPlus && !Func->hasPrototype()) { 1146 // C99 DR 316 says that, if a function type comes from a 1147 // function definition (without a prototype), that type is only 1148 // used for checking compatibility. Therefore, when referencing 1149 // the function, we pretend that we don't have the full function 1150 // type. 1151 if (DiagnoseUseOfDecl(Func, NameLoc)) 1152 return ExprError(); 1153 1154 QualType T = Func->getType(); 1155 QualType NoProtoType = T; 1156 if (const FunctionProtoType *Proto = T->getAs<FunctionProtoType>()) 1157 NoProtoType = Context.getFunctionNoProtoType(Proto->getResultType()); 1158 return BuildDeclRefExpr(Func, NoProtoType, NameLoc, &SS); 1159 } 1160 } 1161 1162 // Check whether this might be a C++ implicit instance member access. 1163 // C++ [expr.prim.general]p6: 1164 // Within the definition of a non-static member function, an 1165 // identifier that names a non-static member is transformed to a 1166 // class member access expression. 1167 // But note that &SomeClass::foo is grammatically distinct, even 1168 // though we don't parse it that way. 1169 if (!R.empty() && (*R.begin())->isCXXClassMember()) { 1170 bool isAbstractMemberPointer = (isAddressOfOperand && !SS.isEmpty()); 1171 if (!isAbstractMemberPointer) 1172 return BuildPossibleImplicitMemberExpr(SS, R, TemplateArgs); 1173 } 1174 1175 if (TemplateArgs) 1176 return BuildTemplateIdExpr(SS, R, ADL, *TemplateArgs); 1177 1178 return BuildDeclarationNameExpr(SS, R, ADL); 1179} 1180 1181/// Builds an expression which might be an implicit member expression. 1182Sema::OwningExprResult 1183Sema::BuildPossibleImplicitMemberExpr(const CXXScopeSpec &SS, 1184 LookupResult &R, 1185 const TemplateArgumentListInfo *TemplateArgs) { 1186 switch (ClassifyImplicitMemberAccess(*this, R)) { 1187 case IMA_Instance: 1188 return BuildImplicitMemberExpr(SS, R, TemplateArgs, true); 1189 1190 case IMA_AnonymousMember: 1191 assert(R.isSingleResult()); 1192 return BuildAnonymousStructUnionMemberReference(R.getNameLoc(), 1193 R.getAsSingle<FieldDecl>()); 1194 1195 case IMA_Mixed: 1196 case IMA_Mixed_Unrelated: 1197 case IMA_Unresolved: 1198 return BuildImplicitMemberExpr(SS, R, TemplateArgs, false); 1199 1200 case IMA_Static: 1201 case IMA_Mixed_StaticContext: 1202 case IMA_Unresolved_StaticContext: 1203 if (TemplateArgs) 1204 return BuildTemplateIdExpr(SS, R, false, *TemplateArgs); 1205 return BuildDeclarationNameExpr(SS, R, false); 1206 1207 case IMA_Error_StaticContext: 1208 case IMA_Error_Unrelated: 1209 DiagnoseInstanceReference(*this, SS, R); 1210 return ExprError(); 1211 } 1212 1213 llvm_unreachable("unexpected instance member access kind"); 1214 return ExprError(); 1215} 1216 1217/// BuildQualifiedDeclarationNameExpr - Build a C++ qualified 1218/// declaration name, generally during template instantiation. 1219/// There's a large number of things which don't need to be done along 1220/// this path. 1221Sema::OwningExprResult 1222Sema::BuildQualifiedDeclarationNameExpr(const CXXScopeSpec &SS, 1223 DeclarationName Name, 1224 SourceLocation NameLoc) { 1225 DeclContext *DC; 1226 if (!(DC = computeDeclContext(SS, false)) || 1227 DC->isDependentContext() || 1228 RequireCompleteDeclContext(SS)) 1229 return BuildDependentDeclRefExpr(SS, Name, NameLoc, 0); 1230 1231 LookupResult R(*this, Name, NameLoc, LookupOrdinaryName); 1232 LookupQualifiedName(R, DC); 1233 1234 if (R.isAmbiguous()) 1235 return ExprError(); 1236 1237 if (R.empty()) { 1238 Diag(NameLoc, diag::err_no_member) << Name << DC << SS.getRange(); 1239 return ExprError(); 1240 } 1241 1242 return BuildDeclarationNameExpr(SS, R, /*ADL*/ false); 1243} 1244 1245/// LookupInObjCMethod - The parser has read a name in, and Sema has 1246/// detected that we're currently inside an ObjC method. Perform some 1247/// additional lookup. 1248/// 1249/// Ideally, most of this would be done by lookup, but there's 1250/// actually quite a lot of extra work involved. 1251/// 1252/// Returns a null sentinel to indicate trivial success. 1253Sema::OwningExprResult 1254Sema::LookupInObjCMethod(LookupResult &Lookup, Scope *S, 1255 IdentifierInfo *II, 1256 bool AllowBuiltinCreation) { 1257 SourceLocation Loc = Lookup.getNameLoc(); 1258 1259 // There are two cases to handle here. 1) scoped lookup could have failed, 1260 // in which case we should look for an ivar. 2) scoped lookup could have 1261 // found a decl, but that decl is outside the current instance method (i.e. 1262 // a global variable). In these two cases, we do a lookup for an ivar with 1263 // this name, if the lookup sucedes, we replace it our current decl. 1264 1265 // If we're in a class method, we don't normally want to look for 1266 // ivars. But if we don't find anything else, and there's an 1267 // ivar, that's an error. 1268 bool IsClassMethod = getCurMethodDecl()->isClassMethod(); 1269 1270 bool LookForIvars; 1271 if (Lookup.empty()) 1272 LookForIvars = true; 1273 else if (IsClassMethod) 1274 LookForIvars = false; 1275 else 1276 LookForIvars = (Lookup.isSingleResult() && 1277 Lookup.getFoundDecl()->isDefinedOutsideFunctionOrMethod()); 1278 ObjCInterfaceDecl *IFace = 0; 1279 if (LookForIvars) { 1280 IFace = getCurMethodDecl()->getClassInterface(); 1281 ObjCInterfaceDecl *ClassDeclared; 1282 if (ObjCIvarDecl *IV = IFace->lookupInstanceVariable(II, ClassDeclared)) { 1283 // Diagnose using an ivar in a class method. 1284 if (IsClassMethod) 1285 return ExprError(Diag(Loc, diag::error_ivar_use_in_class_method) 1286 << IV->getDeclName()); 1287 1288 // If we're referencing an invalid decl, just return this as a silent 1289 // error node. The error diagnostic was already emitted on the decl. 1290 if (IV->isInvalidDecl()) 1291 return ExprError(); 1292 1293 // Check if referencing a field with __attribute__((deprecated)). 1294 if (DiagnoseUseOfDecl(IV, Loc)) 1295 return ExprError(); 1296 1297 // Diagnose the use of an ivar outside of the declaring class. 1298 if (IV->getAccessControl() == ObjCIvarDecl::Private && 1299 ClassDeclared != IFace) 1300 Diag(Loc, diag::error_private_ivar_access) << IV->getDeclName(); 1301 1302 // FIXME: This should use a new expr for a direct reference, don't 1303 // turn this into Self->ivar, just return a BareIVarExpr or something. 1304 IdentifierInfo &II = Context.Idents.get("self"); 1305 UnqualifiedId SelfName; 1306 SelfName.setIdentifier(&II, SourceLocation()); 1307 CXXScopeSpec SelfScopeSpec; 1308 OwningExprResult SelfExpr = ActOnIdExpression(S, SelfScopeSpec, 1309 SelfName, false, false); 1310 MarkDeclarationReferenced(Loc, IV); 1311 return Owned(new (Context) 1312 ObjCIvarRefExpr(IV, IV->getType(), Loc, 1313 SelfExpr.takeAs<Expr>(), true, true)); 1314 } 1315 } else if (getCurMethodDecl()->isInstanceMethod()) { 1316 // We should warn if a local variable hides an ivar. 1317 ObjCInterfaceDecl *IFace = getCurMethodDecl()->getClassInterface(); 1318 ObjCInterfaceDecl *ClassDeclared; 1319 if (ObjCIvarDecl *IV = IFace->lookupInstanceVariable(II, ClassDeclared)) { 1320 if (IV->getAccessControl() != ObjCIvarDecl::Private || 1321 IFace == ClassDeclared) 1322 Diag(Loc, diag::warn_ivar_use_hidden) << IV->getDeclName(); 1323 } 1324 } 1325 1326 // Needed to implement property "super.method" notation. 1327 if (Lookup.empty() && II->isStr("super")) { 1328 QualType T; 1329 1330 if (getCurMethodDecl()->isInstanceMethod()) 1331 T = Context.getObjCObjectPointerType(Context.getObjCInterfaceType( 1332 getCurMethodDecl()->getClassInterface())); 1333 else 1334 T = Context.getObjCClassType(); 1335 return Owned(new (Context) ObjCSuperExpr(Loc, T)); 1336 } 1337 if (Lookup.empty() && II && AllowBuiltinCreation) { 1338 // FIXME. Consolidate this with similar code in LookupName. 1339 if (unsigned BuiltinID = II->getBuiltinID()) { 1340 if (!(getLangOptions().CPlusPlus && 1341 Context.BuiltinInfo.isPredefinedLibFunction(BuiltinID))) { 1342 NamedDecl *D = LazilyCreateBuiltin((IdentifierInfo *)II, BuiltinID, 1343 S, Lookup.isForRedeclaration(), 1344 Lookup.getNameLoc()); 1345 if (D) Lookup.addDecl(D); 1346 } 1347 } 1348 } 1349 if (LangOpts.ObjCNonFragileABI2 && LookForIvars && Lookup.empty()) { 1350 ObjCIvarDecl *Ivar = SynthesizeNewPropertyIvar(IFace, II); 1351 if (Ivar) 1352 return LookupInObjCMethod(Lookup, S, II, AllowBuiltinCreation); 1353 } 1354 // Sentinel value saying that we didn't do anything special. 1355 return Owned((Expr*) 0); 1356} 1357 1358/// \brief Cast member's object to its own class if necessary. 1359bool 1360Sema::PerformObjectMemberConversion(Expr *&From, 1361 NestedNameSpecifier *Qualifier, 1362 NamedDecl *Member) { 1363 CXXRecordDecl *RD = dyn_cast<CXXRecordDecl>(Member->getDeclContext()); 1364 if (!RD) 1365 return false; 1366 1367 QualType DestRecordType; 1368 QualType DestType; 1369 QualType FromRecordType; 1370 QualType FromType = From->getType(); 1371 bool PointerConversions = false; 1372 if (isa<FieldDecl>(Member)) { 1373 DestRecordType = Context.getCanonicalType(Context.getTypeDeclType(RD)); 1374 1375 if (FromType->getAs<PointerType>()) { 1376 DestType = Context.getPointerType(DestRecordType); 1377 FromRecordType = FromType->getPointeeType(); 1378 PointerConversions = true; 1379 } else { 1380 DestType = DestRecordType; 1381 FromRecordType = FromType; 1382 } 1383 } else if (CXXMethodDecl *Method = dyn_cast<CXXMethodDecl>(Member)) { 1384 if (Method->isStatic()) 1385 return false; 1386 1387 DestType = Method->getThisType(Context); 1388 DestRecordType = DestType->getPointeeType(); 1389 1390 if (FromType->getAs<PointerType>()) { 1391 FromRecordType = FromType->getPointeeType(); 1392 PointerConversions = true; 1393 } else { 1394 FromRecordType = FromType; 1395 DestType = DestRecordType; 1396 } 1397 } else { 1398 // No conversion necessary. 1399 return false; 1400 } 1401 1402 if (DestType->isDependentType() || FromType->isDependentType()) 1403 return false; 1404 1405 // If the unqualified types are the same, no conversion is necessary. 1406 if (Context.hasSameUnqualifiedType(FromRecordType, DestRecordType)) 1407 return false; 1408 1409 // C++ [class.member.lookup]p8: 1410 // [...] Ambiguities can often be resolved by qualifying a name with its 1411 // class name. 1412 // 1413 // If the member was a qualified name and the qualified referred to a 1414 // specific base subobject type, we'll cast to that intermediate type 1415 // first and then to the object in which the member is declared. That allows 1416 // one to resolve ambiguities in, e.g., a diamond-shaped hierarchy such as: 1417 // 1418 // class Base { public: int x; }; 1419 // class Derived1 : public Base { }; 1420 // class Derived2 : public Base { }; 1421 // class VeryDerived : public Derived1, public Derived2 { void f(); }; 1422 // 1423 // void VeryDerived::f() { 1424 // x = 17; // error: ambiguous base subobjects 1425 // Derived1::x = 17; // okay, pick the Base subobject of Derived1 1426 // } 1427 QualType IntermediateRecordType; 1428 QualType IntermediateType; 1429 if (Qualifier) { 1430 if (const RecordType *IntermediateRecord 1431 = Qualifier->getAsType()->getAs<RecordType>()) { 1432 IntermediateRecordType = QualType(IntermediateRecord, 0); 1433 IntermediateType = IntermediateRecordType; 1434 if (PointerConversions) 1435 IntermediateType = Context.getPointerType(IntermediateType); 1436 } 1437 } 1438 1439 if (!IntermediateType.isNull() && 1440 IsDerivedFrom(FromRecordType, IntermediateRecordType) && 1441 IsDerivedFrom(IntermediateRecordType, DestRecordType)) { 1442 if (CheckDerivedToBaseConversion(FromRecordType, IntermediateRecordType, 1443 From->getSourceRange().getBegin(), 1444 From->getSourceRange()) || 1445 CheckDerivedToBaseConversion(IntermediateRecordType, DestRecordType, 1446 From->getSourceRange().getBegin(), 1447 From->getSourceRange())) 1448 return true; 1449 1450 ImpCastExprToType(From, IntermediateType, CastExpr::CK_DerivedToBase, 1451 /*isLvalue=*/!PointerConversions); 1452 ImpCastExprToType(From, DestType, CastExpr::CK_DerivedToBase, 1453 /*isLvalue=*/!PointerConversions); 1454 return false; 1455 } 1456 1457 if (CheckDerivedToBaseConversion(FromRecordType, 1458 DestRecordType, 1459 From->getSourceRange().getBegin(), 1460 From->getSourceRange())) 1461 return true; 1462 1463 ImpCastExprToType(From, DestType, CastExpr::CK_DerivedToBase, 1464 /*isLvalue=*/true); 1465 return false; 1466} 1467 1468/// \brief Build a MemberExpr AST node. 1469static MemberExpr *BuildMemberExpr(ASTContext &C, Expr *Base, bool isArrow, 1470 const CXXScopeSpec &SS, ValueDecl *Member, 1471 SourceLocation Loc, QualType Ty, 1472 const TemplateArgumentListInfo *TemplateArgs = 0) { 1473 NestedNameSpecifier *Qualifier = 0; 1474 SourceRange QualifierRange; 1475 if (SS.isSet()) { 1476 Qualifier = (NestedNameSpecifier *) SS.getScopeRep(); 1477 QualifierRange = SS.getRange(); 1478 } 1479 1480 return MemberExpr::Create(C, Base, isArrow, Qualifier, QualifierRange, 1481 Member, Loc, TemplateArgs, Ty); 1482} 1483 1484/// Builds an implicit member access expression. The current context 1485/// is known to be an instance method, and the given unqualified lookup 1486/// set is known to contain only instance members, at least one of which 1487/// is from an appropriate type. 1488Sema::OwningExprResult 1489Sema::BuildImplicitMemberExpr(const CXXScopeSpec &SS, 1490 LookupResult &R, 1491 const TemplateArgumentListInfo *TemplateArgs, 1492 bool IsKnownInstance) { 1493 assert(!R.empty() && !R.isAmbiguous()); 1494 1495 SourceLocation Loc = R.getNameLoc(); 1496 1497 // We may have found a field within an anonymous union or struct 1498 // (C++ [class.union]). 1499 // FIXME: This needs to happen post-isImplicitMemberReference? 1500 // FIXME: template-ids inside anonymous structs? 1501 if (FieldDecl *FD = R.getAsSingle<FieldDecl>()) 1502 if (cast<RecordDecl>(FD->getDeclContext())->isAnonymousStructOrUnion()) 1503 return BuildAnonymousStructUnionMemberReference(Loc, FD); 1504 1505 // If this is known to be an instance access, go ahead and build a 1506 // 'this' expression now. 1507 QualType ThisType = cast<CXXMethodDecl>(CurContext)->getThisType(Context); 1508 Expr *This = 0; // null signifies implicit access 1509 if (IsKnownInstance) { 1510 SourceLocation Loc = R.getNameLoc(); 1511 if (SS.getRange().isValid()) 1512 Loc = SS.getRange().getBegin(); 1513 This = new (Context) CXXThisExpr(Loc, ThisType, /*isImplicit=*/true); 1514 } 1515 1516 return BuildMemberReferenceExpr(ExprArg(*this, This), ThisType, 1517 /*OpLoc*/ SourceLocation(), 1518 /*IsArrow*/ true, 1519 SS, 1520 /*FirstQualifierInScope*/ 0, 1521 R, TemplateArgs); 1522} 1523 1524bool Sema::UseArgumentDependentLookup(const CXXScopeSpec &SS, 1525 const LookupResult &R, 1526 bool HasTrailingLParen) { 1527 // Only when used directly as the postfix-expression of a call. 1528 if (!HasTrailingLParen) 1529 return false; 1530 1531 // Never if a scope specifier was provided. 1532 if (SS.isSet()) 1533 return false; 1534 1535 // Only in C++ or ObjC++. 1536 if (!getLangOptions().CPlusPlus) 1537 return false; 1538 1539 // Turn off ADL when we find certain kinds of declarations during 1540 // normal lookup: 1541 for (LookupResult::iterator I = R.begin(), E = R.end(); I != E; ++I) { 1542 NamedDecl *D = *I; 1543 1544 // C++0x [basic.lookup.argdep]p3: 1545 // -- a declaration of a class member 1546 // Since using decls preserve this property, we check this on the 1547 // original decl. 1548 if (D->isCXXClassMember()) 1549 return false; 1550 1551 // C++0x [basic.lookup.argdep]p3: 1552 // -- a block-scope function declaration that is not a 1553 // using-declaration 1554 // NOTE: we also trigger this for function templates (in fact, we 1555 // don't check the decl type at all, since all other decl types 1556 // turn off ADL anyway). 1557 if (isa<UsingShadowDecl>(D)) 1558 D = cast<UsingShadowDecl>(D)->getTargetDecl(); 1559 else if (D->getDeclContext()->isFunctionOrMethod()) 1560 return false; 1561 1562 // C++0x [basic.lookup.argdep]p3: 1563 // -- a declaration that is neither a function or a function 1564 // template 1565 // And also for builtin functions. 1566 if (isa<FunctionDecl>(D)) { 1567 FunctionDecl *FDecl = cast<FunctionDecl>(D); 1568 1569 // But also builtin functions. 1570 if (FDecl->getBuiltinID() && FDecl->isImplicit()) 1571 return false; 1572 } else if (!isa<FunctionTemplateDecl>(D)) 1573 return false; 1574 } 1575 1576 return true; 1577} 1578 1579 1580/// Diagnoses obvious problems with the use of the given declaration 1581/// as an expression. This is only actually called for lookups that 1582/// were not overloaded, and it doesn't promise that the declaration 1583/// will in fact be used. 1584static bool CheckDeclInExpr(Sema &S, SourceLocation Loc, NamedDecl *D) { 1585 if (isa<TypedefDecl>(D)) { 1586 S.Diag(Loc, diag::err_unexpected_typedef) << D->getDeclName(); 1587 return true; 1588 } 1589 1590 if (isa<ObjCInterfaceDecl>(D)) { 1591 S.Diag(Loc, diag::err_unexpected_interface) << D->getDeclName(); 1592 return true; 1593 } 1594 1595 if (isa<NamespaceDecl>(D)) { 1596 S.Diag(Loc, diag::err_unexpected_namespace) << D->getDeclName(); 1597 return true; 1598 } 1599 1600 return false; 1601} 1602 1603Sema::OwningExprResult 1604Sema::BuildDeclarationNameExpr(const CXXScopeSpec &SS, 1605 LookupResult &R, 1606 bool NeedsADL) { 1607 // If this is a single, fully-resolved result and we don't need ADL, 1608 // just build an ordinary singleton decl ref. 1609 if (!NeedsADL && R.isSingleResult() && !R.getAsSingle<FunctionTemplateDecl>()) 1610 return BuildDeclarationNameExpr(SS, R.getNameLoc(), R.getFoundDecl()); 1611 1612 // We only need to check the declaration if there's exactly one 1613 // result, because in the overloaded case the results can only be 1614 // functions and function templates. 1615 if (R.isSingleResult() && 1616 CheckDeclInExpr(*this, R.getNameLoc(), R.getFoundDecl())) 1617 return ExprError(); 1618 1619 // Otherwise, just build an unresolved lookup expression. Suppress 1620 // any lookup-related diagnostics; we'll hash these out later, when 1621 // we've picked a target. 1622 R.suppressDiagnostics(); 1623 1624 bool Dependent 1625 = UnresolvedLookupExpr::ComputeDependence(R.begin(), R.end(), 0); 1626 UnresolvedLookupExpr *ULE 1627 = UnresolvedLookupExpr::Create(Context, Dependent, R.getNamingClass(), 1628 (NestedNameSpecifier*) SS.getScopeRep(), 1629 SS.getRange(), 1630 R.getLookupName(), R.getNameLoc(), 1631 NeedsADL, R.isOverloadedResult()); 1632 ULE->addDecls(R.begin(), R.end()); 1633 1634 return Owned(ULE); 1635} 1636 1637 1638/// \brief Complete semantic analysis for a reference to the given declaration. 1639Sema::OwningExprResult 1640Sema::BuildDeclarationNameExpr(const CXXScopeSpec &SS, 1641 SourceLocation Loc, NamedDecl *D) { 1642 assert(D && "Cannot refer to a NULL declaration"); 1643 assert(!isa<FunctionTemplateDecl>(D) && 1644 "Cannot refer unambiguously to a function template"); 1645 1646 if (CheckDeclInExpr(*this, Loc, D)) 1647 return ExprError(); 1648 1649 if (TemplateDecl *Template = dyn_cast<TemplateDecl>(D)) { 1650 // Specifically diagnose references to class templates that are missing 1651 // a template argument list. 1652 Diag(Loc, diag::err_template_decl_ref) 1653 << Template << SS.getRange(); 1654 Diag(Template->getLocation(), diag::note_template_decl_here); 1655 return ExprError(); 1656 } 1657 1658 // Make sure that we're referring to a value. 1659 ValueDecl *VD = dyn_cast<ValueDecl>(D); 1660 if (!VD) { 1661 Diag(Loc, diag::err_ref_non_value) 1662 << D << SS.getRange(); 1663 Diag(D->getLocation(), diag::note_declared_at); 1664 return ExprError(); 1665 } 1666 1667 // Check whether this declaration can be used. Note that we suppress 1668 // this check when we're going to perform argument-dependent lookup 1669 // on this function name, because this might not be the function 1670 // that overload resolution actually selects. 1671 if (DiagnoseUseOfDecl(VD, Loc)) 1672 return ExprError(); 1673 1674 // Only create DeclRefExpr's for valid Decl's. 1675 if (VD->isInvalidDecl()) 1676 return ExprError(); 1677 1678 // If the identifier reference is inside a block, and it refers to a value 1679 // that is outside the block, create a BlockDeclRefExpr instead of a 1680 // DeclRefExpr. This ensures the value is treated as a copy-in snapshot when 1681 // the block is formed. 1682 // 1683 // We do not do this for things like enum constants, global variables, etc, 1684 // as they do not get snapshotted. 1685 // 1686 if (getCurBlock() && 1687 ShouldSnapshotBlockValueReference(*this, getCurBlock(), VD)) { 1688 if (VD->getType().getTypePtr()->isVariablyModifiedType()) { 1689 Diag(Loc, diag::err_ref_vm_type); 1690 Diag(D->getLocation(), diag::note_declared_at); 1691 return ExprError(); 1692 } 1693 1694 if (VD->getType()->isArrayType() && !VD->hasAttr<BlocksAttr>()) { 1695 Diag(Loc, diag::err_ref_array_type); 1696 Diag(D->getLocation(), diag::note_declared_at); 1697 return ExprError(); 1698 } 1699 1700 MarkDeclarationReferenced(Loc, VD); 1701 QualType ExprTy = VD->getType().getNonReferenceType(); 1702 // The BlocksAttr indicates the variable is bound by-reference. 1703 if (VD->getAttr<BlocksAttr>()) 1704 return Owned(new (Context) BlockDeclRefExpr(VD, ExprTy, Loc, true)); 1705 // This is to record that a 'const' was actually synthesize and added. 1706 bool constAdded = !ExprTy.isConstQualified(); 1707 // Variable will be bound by-copy, make it const within the closure. 1708 1709 ExprTy.addConst(); 1710 return Owned(new (Context) BlockDeclRefExpr(VD, ExprTy, Loc, false, 1711 constAdded)); 1712 } 1713 // If this reference is not in a block or if the referenced variable is 1714 // within the block, create a normal DeclRefExpr. 1715 1716 return BuildDeclRefExpr(VD, VD->getType().getNonReferenceType(), Loc, &SS); 1717} 1718 1719Sema::OwningExprResult Sema::ActOnPredefinedExpr(SourceLocation Loc, 1720 tok::TokenKind Kind) { 1721 PredefinedExpr::IdentType IT; 1722 1723 switch (Kind) { 1724 default: assert(0 && "Unknown simple primary expr!"); 1725 case tok::kw___func__: IT = PredefinedExpr::Func; break; // [C99 6.4.2.2] 1726 case tok::kw___FUNCTION__: IT = PredefinedExpr::Function; break; 1727 case tok::kw___PRETTY_FUNCTION__: IT = PredefinedExpr::PrettyFunction; break; 1728 } 1729 1730 // Pre-defined identifiers are of type char[x], where x is the length of the 1731 // string. 1732 1733 Decl *currentDecl = getCurFunctionOrMethodDecl(); 1734 if (!currentDecl) { 1735 Diag(Loc, diag::ext_predef_outside_function); 1736 currentDecl = Context.getTranslationUnitDecl(); 1737 } 1738 1739 QualType ResTy; 1740 if (cast<DeclContext>(currentDecl)->isDependentContext()) { 1741 ResTy = Context.DependentTy; 1742 } else { 1743 unsigned Length = PredefinedExpr::ComputeName(IT, currentDecl).length(); 1744 1745 llvm::APInt LengthI(32, Length + 1); 1746 ResTy = Context.CharTy.withConst(); 1747 ResTy = Context.getConstantArrayType(ResTy, LengthI, ArrayType::Normal, 0); 1748 } 1749 return Owned(new (Context) PredefinedExpr(Loc, ResTy, IT)); 1750} 1751 1752Sema::OwningExprResult Sema::ActOnCharacterConstant(const Token &Tok) { 1753 llvm::SmallString<16> CharBuffer; 1754 llvm::StringRef ThisTok = PP.getSpelling(Tok, CharBuffer); 1755 1756 CharLiteralParser Literal(ThisTok.begin(), ThisTok.end(), Tok.getLocation(), 1757 PP); 1758 if (Literal.hadError()) 1759 return ExprError(); 1760 1761 QualType Ty; 1762 if (!getLangOptions().CPlusPlus) 1763 Ty = Context.IntTy; // 'x' and L'x' -> int in C. 1764 else if (Literal.isWide()) 1765 Ty = Context.WCharTy; // L'x' -> wchar_t in C++. 1766 else if (Literal.isMultiChar()) 1767 Ty = Context.IntTy; // 'wxyz' -> int in C++. 1768 else 1769 Ty = Context.CharTy; // 'x' -> char in C++ 1770 1771 return Owned(new (Context) CharacterLiteral(Literal.getValue(), 1772 Literal.isWide(), 1773 Ty, Tok.getLocation())); 1774} 1775 1776Action::OwningExprResult Sema::ActOnNumericConstant(const Token &Tok) { 1777 // Fast path for a single digit (which is quite common). A single digit 1778 // cannot have a trigraph, escaped newline, radix prefix, or type suffix. 1779 if (Tok.getLength() == 1) { 1780 const char Val = PP.getSpellingOfSingleCharacterNumericConstant(Tok); 1781 unsigned IntSize = Context.Target.getIntWidth(); 1782 return Owned(new (Context) IntegerLiteral(llvm::APInt(IntSize, Val-'0'), 1783 Context.IntTy, Tok.getLocation())); 1784 } 1785 1786 llvm::SmallString<512> IntegerBuffer; 1787 // Add padding so that NumericLiteralParser can overread by one character. 1788 IntegerBuffer.resize(Tok.getLength()+1); 1789 const char *ThisTokBegin = &IntegerBuffer[0]; 1790 1791 // Get the spelling of the token, which eliminates trigraphs, etc. 1792 unsigned ActualLength = PP.getSpelling(Tok, ThisTokBegin); 1793 1794 NumericLiteralParser Literal(ThisTokBegin, ThisTokBegin+ActualLength, 1795 Tok.getLocation(), PP); 1796 if (Literal.hadError) 1797 return ExprError(); 1798 1799 Expr *Res; 1800 1801 if (Literal.isFloatingLiteral()) { 1802 QualType Ty; 1803 if (Literal.isFloat) 1804 Ty = Context.FloatTy; 1805 else if (!Literal.isLong) 1806 Ty = Context.DoubleTy; 1807 else 1808 Ty = Context.LongDoubleTy; 1809 1810 const llvm::fltSemantics &Format = Context.getFloatTypeSemantics(Ty); 1811 1812 using llvm::APFloat; 1813 APFloat Val(Format); 1814 1815 APFloat::opStatus result = Literal.GetFloatValue(Val); 1816 1817 // Overflow is always an error, but underflow is only an error if 1818 // we underflowed to zero (APFloat reports denormals as underflow). 1819 if ((result & APFloat::opOverflow) || 1820 ((result & APFloat::opUnderflow) && Val.isZero())) { 1821 unsigned diagnostic; 1822 llvm::SmallString<20> buffer; 1823 if (result & APFloat::opOverflow) { 1824 diagnostic = diag::warn_float_overflow; 1825 APFloat::getLargest(Format).toString(buffer); 1826 } else { 1827 diagnostic = diag::warn_float_underflow; 1828 APFloat::getSmallest(Format).toString(buffer); 1829 } 1830 1831 Diag(Tok.getLocation(), diagnostic) 1832 << Ty 1833 << llvm::StringRef(buffer.data(), buffer.size()); 1834 } 1835 1836 bool isExact = (result == APFloat::opOK); 1837 Res = new (Context) FloatingLiteral(Val, isExact, Ty, Tok.getLocation()); 1838 1839 } else if (!Literal.isIntegerLiteral()) { 1840 return ExprError(); 1841 } else { 1842 QualType Ty; 1843 1844 // long long is a C99 feature. 1845 if (!getLangOptions().C99 && !getLangOptions().CPlusPlus0x && 1846 Literal.isLongLong) 1847 Diag(Tok.getLocation(), diag::ext_longlong); 1848 1849 // Get the value in the widest-possible width. 1850 llvm::APInt ResultVal(Context.Target.getIntMaxTWidth(), 0); 1851 1852 if (Literal.GetIntegerValue(ResultVal)) { 1853 // If this value didn't fit into uintmax_t, warn and force to ull. 1854 Diag(Tok.getLocation(), diag::warn_integer_too_large); 1855 Ty = Context.UnsignedLongLongTy; 1856 assert(Context.getTypeSize(Ty) == ResultVal.getBitWidth() && 1857 "long long is not intmax_t?"); 1858 } else { 1859 // If this value fits into a ULL, try to figure out what else it fits into 1860 // according to the rules of C99 6.4.4.1p5. 1861 1862 // Octal, Hexadecimal, and integers with a U suffix are allowed to 1863 // be an unsigned int. 1864 bool AllowUnsigned = Literal.isUnsigned || Literal.getRadix() != 10; 1865 1866 // Check from smallest to largest, picking the smallest type we can. 1867 unsigned Width = 0; 1868 if (!Literal.isLong && !Literal.isLongLong) { 1869 // Are int/unsigned possibilities? 1870 unsigned IntSize = Context.Target.getIntWidth(); 1871 1872 // Does it fit in a unsigned int? 1873 if (ResultVal.isIntN(IntSize)) { 1874 // Does it fit in a signed int? 1875 if (!Literal.isUnsigned && ResultVal[IntSize-1] == 0) 1876 Ty = Context.IntTy; 1877 else if (AllowUnsigned) 1878 Ty = Context.UnsignedIntTy; 1879 Width = IntSize; 1880 } 1881 } 1882 1883 // Are long/unsigned long possibilities? 1884 if (Ty.isNull() && !Literal.isLongLong) { 1885 unsigned LongSize = Context.Target.getLongWidth(); 1886 1887 // Does it fit in a unsigned long? 1888 if (ResultVal.isIntN(LongSize)) { 1889 // Does it fit in a signed long? 1890 if (!Literal.isUnsigned && ResultVal[LongSize-1] == 0) 1891 Ty = Context.LongTy; 1892 else if (AllowUnsigned) 1893 Ty = Context.UnsignedLongTy; 1894 Width = LongSize; 1895 } 1896 } 1897 1898 // Finally, check long long if needed. 1899 if (Ty.isNull()) { 1900 unsigned LongLongSize = Context.Target.getLongLongWidth(); 1901 1902 // Does it fit in a unsigned long long? 1903 if (ResultVal.isIntN(LongLongSize)) { 1904 // Does it fit in a signed long long? 1905 if (!Literal.isUnsigned && ResultVal[LongLongSize-1] == 0) 1906 Ty = Context.LongLongTy; 1907 else if (AllowUnsigned) 1908 Ty = Context.UnsignedLongLongTy; 1909 Width = LongLongSize; 1910 } 1911 } 1912 1913 // If we still couldn't decide a type, we probably have something that 1914 // does not fit in a signed long long, but has no U suffix. 1915 if (Ty.isNull()) { 1916 Diag(Tok.getLocation(), diag::warn_integer_too_large_for_signed); 1917 Ty = Context.UnsignedLongLongTy; 1918 Width = Context.Target.getLongLongWidth(); 1919 } 1920 1921 if (ResultVal.getBitWidth() != Width) 1922 ResultVal.trunc(Width); 1923 } 1924 Res = new (Context) IntegerLiteral(ResultVal, Ty, Tok.getLocation()); 1925 } 1926 1927 // If this is an imaginary literal, create the ImaginaryLiteral wrapper. 1928 if (Literal.isImaginary) 1929 Res = new (Context) ImaginaryLiteral(Res, 1930 Context.getComplexType(Res->getType())); 1931 1932 return Owned(Res); 1933} 1934 1935Action::OwningExprResult Sema::ActOnParenExpr(SourceLocation L, 1936 SourceLocation R, ExprArg Val) { 1937 Expr *E = Val.takeAs<Expr>(); 1938 assert((E != 0) && "ActOnParenExpr() missing expr"); 1939 return Owned(new (Context) ParenExpr(L, R, E)); 1940} 1941 1942/// The UsualUnaryConversions() function is *not* called by this routine. 1943/// See C99 6.3.2.1p[2-4] for more details. 1944bool Sema::CheckSizeOfAlignOfOperand(QualType exprType, 1945 SourceLocation OpLoc, 1946 const SourceRange &ExprRange, 1947 bool isSizeof) { 1948 if (exprType->isDependentType()) 1949 return false; 1950 1951 // C++ [expr.sizeof]p2: "When applied to a reference or a reference type, 1952 // the result is the size of the referenced type." 1953 // C++ [expr.alignof]p3: "When alignof is applied to a reference type, the 1954 // result shall be the alignment of the referenced type." 1955 if (const ReferenceType *Ref = exprType->getAs<ReferenceType>()) 1956 exprType = Ref->getPointeeType(); 1957 1958 // C99 6.5.3.4p1: 1959 if (exprType->isFunctionType()) { 1960 // alignof(function) is allowed as an extension. 1961 if (isSizeof) 1962 Diag(OpLoc, diag::ext_sizeof_function_type) << ExprRange; 1963 return false; 1964 } 1965 1966 // Allow sizeof(void)/alignof(void) as an extension. 1967 if (exprType->isVoidType()) { 1968 Diag(OpLoc, diag::ext_sizeof_void_type) 1969 << (isSizeof ? "sizeof" : "__alignof") << ExprRange; 1970 return false; 1971 } 1972 1973 if (RequireCompleteType(OpLoc, exprType, 1974 PDiag(diag::err_sizeof_alignof_incomplete_type) 1975 << int(!isSizeof) << ExprRange)) 1976 return true; 1977 1978 // Reject sizeof(interface) and sizeof(interface<proto>) in 64-bit mode. 1979 if (LangOpts.ObjCNonFragileABI && exprType->isObjCInterfaceType()) { 1980 Diag(OpLoc, diag::err_sizeof_nonfragile_interface) 1981 << exprType << isSizeof << ExprRange; 1982 return true; 1983 } 1984 1985 return false; 1986} 1987 1988bool Sema::CheckAlignOfExpr(Expr *E, SourceLocation OpLoc, 1989 const SourceRange &ExprRange) { 1990 E = E->IgnoreParens(); 1991 1992 // alignof decl is always ok. 1993 if (isa<DeclRefExpr>(E)) 1994 return false; 1995 1996 // Cannot know anything else if the expression is dependent. 1997 if (E->isTypeDependent()) 1998 return false; 1999 2000 if (E->getBitField()) { 2001 Diag(OpLoc, diag::err_sizeof_alignof_bitfield) << 1 << ExprRange; 2002 return true; 2003 } 2004 2005 // Alignment of a field access is always okay, so long as it isn't a 2006 // bit-field. 2007 if (MemberExpr *ME = dyn_cast<MemberExpr>(E)) 2008 if (isa<FieldDecl>(ME->getMemberDecl())) 2009 return false; 2010 2011 return CheckSizeOfAlignOfOperand(E->getType(), OpLoc, ExprRange, false); 2012} 2013 2014/// \brief Build a sizeof or alignof expression given a type operand. 2015Action::OwningExprResult 2016Sema::CreateSizeOfAlignOfExpr(TypeSourceInfo *TInfo, 2017 SourceLocation OpLoc, 2018 bool isSizeOf, SourceRange R) { 2019 if (!TInfo) 2020 return ExprError(); 2021 2022 QualType T = TInfo->getType(); 2023 2024 if (!T->isDependentType() && 2025 CheckSizeOfAlignOfOperand(T, OpLoc, R, isSizeOf)) 2026 return ExprError(); 2027 2028 // C99 6.5.3.4p4: the type (an unsigned integer type) is size_t. 2029 return Owned(new (Context) SizeOfAlignOfExpr(isSizeOf, TInfo, 2030 Context.getSizeType(), OpLoc, 2031 R.getEnd())); 2032} 2033 2034/// \brief Build a sizeof or alignof expression given an expression 2035/// operand. 2036Action::OwningExprResult 2037Sema::CreateSizeOfAlignOfExpr(Expr *E, SourceLocation OpLoc, 2038 bool isSizeOf, SourceRange R) { 2039 // Verify that the operand is valid. 2040 bool isInvalid = false; 2041 if (E->isTypeDependent()) { 2042 // Delay type-checking for type-dependent expressions. 2043 } else if (!isSizeOf) { 2044 isInvalid = CheckAlignOfExpr(E, OpLoc, R); 2045 } else if (E->getBitField()) { // C99 6.5.3.4p1. 2046 Diag(OpLoc, diag::err_sizeof_alignof_bitfield) << 0; 2047 isInvalid = true; 2048 } else { 2049 isInvalid = CheckSizeOfAlignOfOperand(E->getType(), OpLoc, R, true); 2050 } 2051 2052 if (isInvalid) 2053 return ExprError(); 2054 2055 // C99 6.5.3.4p4: the type (an unsigned integer type) is size_t. 2056 return Owned(new (Context) SizeOfAlignOfExpr(isSizeOf, E, 2057 Context.getSizeType(), OpLoc, 2058 R.getEnd())); 2059} 2060 2061/// ActOnSizeOfAlignOfExpr - Handle @c sizeof(type) and @c sizeof @c expr and 2062/// the same for @c alignof and @c __alignof 2063/// Note that the ArgRange is invalid if isType is false. 2064Action::OwningExprResult 2065Sema::ActOnSizeOfAlignOfExpr(SourceLocation OpLoc, bool isSizeof, bool isType, 2066 void *TyOrEx, const SourceRange &ArgRange) { 2067 // If error parsing type, ignore. 2068 if (TyOrEx == 0) return ExprError(); 2069 2070 if (isType) { 2071 TypeSourceInfo *TInfo; 2072 (void) GetTypeFromParser(TyOrEx, &TInfo); 2073 return CreateSizeOfAlignOfExpr(TInfo, OpLoc, isSizeof, ArgRange); 2074 } 2075 2076 Expr *ArgEx = (Expr *)TyOrEx; 2077 Action::OwningExprResult Result 2078 = CreateSizeOfAlignOfExpr(ArgEx, OpLoc, isSizeof, ArgEx->getSourceRange()); 2079 2080 if (Result.isInvalid()) 2081 DeleteExpr(ArgEx); 2082 2083 return move(Result); 2084} 2085 2086QualType Sema::CheckRealImagOperand(Expr *&V, SourceLocation Loc, bool isReal) { 2087 if (V->isTypeDependent()) 2088 return Context.DependentTy; 2089 2090 // These operators return the element type of a complex type. 2091 if (const ComplexType *CT = V->getType()->getAs<ComplexType>()) 2092 return CT->getElementType(); 2093 2094 // Otherwise they pass through real integer and floating point types here. 2095 if (V->getType()->isArithmeticType()) 2096 return V->getType(); 2097 2098 // Reject anything else. 2099 Diag(Loc, diag::err_realimag_invalid_type) << V->getType() 2100 << (isReal ? "__real" : "__imag"); 2101 return QualType(); 2102} 2103 2104 2105 2106Action::OwningExprResult 2107Sema::ActOnPostfixUnaryOp(Scope *S, SourceLocation OpLoc, 2108 tok::TokenKind Kind, ExprArg Input) { 2109 UnaryOperator::Opcode Opc; 2110 switch (Kind) { 2111 default: assert(0 && "Unknown unary op!"); 2112 case tok::plusplus: Opc = UnaryOperator::PostInc; break; 2113 case tok::minusminus: Opc = UnaryOperator::PostDec; break; 2114 } 2115 2116 return BuildUnaryOp(S, OpLoc, Opc, move(Input)); 2117} 2118 2119Action::OwningExprResult 2120Sema::ActOnArraySubscriptExpr(Scope *S, ExprArg Base, SourceLocation LLoc, 2121 ExprArg Idx, SourceLocation RLoc) { 2122 // Since this might be a postfix expression, get rid of ParenListExprs. 2123 Base = MaybeConvertParenListExprToParenExpr(S, move(Base)); 2124 2125 Expr *LHSExp = static_cast<Expr*>(Base.get()), 2126 *RHSExp = static_cast<Expr*>(Idx.get()); 2127 2128 if (getLangOptions().CPlusPlus && 2129 (LHSExp->isTypeDependent() || RHSExp->isTypeDependent())) { 2130 Base.release(); 2131 Idx.release(); 2132 return Owned(new (Context) ArraySubscriptExpr(LHSExp, RHSExp, 2133 Context.DependentTy, RLoc)); 2134 } 2135 2136 if (getLangOptions().CPlusPlus && 2137 (LHSExp->getType()->isRecordType() || 2138 LHSExp->getType()->isEnumeralType() || 2139 RHSExp->getType()->isRecordType() || 2140 RHSExp->getType()->isEnumeralType())) { 2141 return CreateOverloadedArraySubscriptExpr(LLoc, RLoc, move(Base),move(Idx)); 2142 } 2143 2144 return CreateBuiltinArraySubscriptExpr(move(Base), LLoc, move(Idx), RLoc); 2145} 2146 2147 2148Action::OwningExprResult 2149Sema::CreateBuiltinArraySubscriptExpr(ExprArg Base, SourceLocation LLoc, 2150 ExprArg Idx, SourceLocation RLoc) { 2151 Expr *LHSExp = static_cast<Expr*>(Base.get()); 2152 Expr *RHSExp = static_cast<Expr*>(Idx.get()); 2153 2154 // Perform default conversions. 2155 if (!LHSExp->getType()->getAs<VectorType>()) 2156 DefaultFunctionArrayLvalueConversion(LHSExp); 2157 DefaultFunctionArrayLvalueConversion(RHSExp); 2158 2159 QualType LHSTy = LHSExp->getType(), RHSTy = RHSExp->getType(); 2160 2161 // C99 6.5.2.1p2: the expression e1[e2] is by definition precisely equivalent 2162 // to the expression *((e1)+(e2)). This means the array "Base" may actually be 2163 // in the subscript position. As a result, we need to derive the array base 2164 // and index from the expression types. 2165 Expr *BaseExpr, *IndexExpr; 2166 QualType ResultType; 2167 if (LHSTy->isDependentType() || RHSTy->isDependentType()) { 2168 BaseExpr = LHSExp; 2169 IndexExpr = RHSExp; 2170 ResultType = Context.DependentTy; 2171 } else if (const PointerType *PTy = LHSTy->getAs<PointerType>()) { 2172 BaseExpr = LHSExp; 2173 IndexExpr = RHSExp; 2174 ResultType = PTy->getPointeeType(); 2175 } else if (const PointerType *PTy = RHSTy->getAs<PointerType>()) { 2176 // Handle the uncommon case of "123[Ptr]". 2177 BaseExpr = RHSExp; 2178 IndexExpr = LHSExp; 2179 ResultType = PTy->getPointeeType(); 2180 } else if (const ObjCObjectPointerType *PTy = 2181 LHSTy->getAs<ObjCObjectPointerType>()) { 2182 BaseExpr = LHSExp; 2183 IndexExpr = RHSExp; 2184 ResultType = PTy->getPointeeType(); 2185 } else if (const ObjCObjectPointerType *PTy = 2186 RHSTy->getAs<ObjCObjectPointerType>()) { 2187 // Handle the uncommon case of "123[Ptr]". 2188 BaseExpr = RHSExp; 2189 IndexExpr = LHSExp; 2190 ResultType = PTy->getPointeeType(); 2191 } else if (const VectorType *VTy = LHSTy->getAs<VectorType>()) { 2192 BaseExpr = LHSExp; // vectors: V[123] 2193 IndexExpr = RHSExp; 2194 2195 // FIXME: need to deal with const... 2196 ResultType = VTy->getElementType(); 2197 } else if (LHSTy->isArrayType()) { 2198 // If we see an array that wasn't promoted by 2199 // DefaultFunctionArrayLvalueConversion, it must be an array that 2200 // wasn't promoted because of the C90 rule that doesn't 2201 // allow promoting non-lvalue arrays. Warn, then 2202 // force the promotion here. 2203 Diag(LHSExp->getLocStart(), diag::ext_subscript_non_lvalue) << 2204 LHSExp->getSourceRange(); 2205 ImpCastExprToType(LHSExp, Context.getArrayDecayedType(LHSTy), 2206 CastExpr::CK_ArrayToPointerDecay); 2207 LHSTy = LHSExp->getType(); 2208 2209 BaseExpr = LHSExp; 2210 IndexExpr = RHSExp; 2211 ResultType = LHSTy->getAs<PointerType>()->getPointeeType(); 2212 } else if (RHSTy->isArrayType()) { 2213 // Same as previous, except for 123[f().a] case 2214 Diag(RHSExp->getLocStart(), diag::ext_subscript_non_lvalue) << 2215 RHSExp->getSourceRange(); 2216 ImpCastExprToType(RHSExp, Context.getArrayDecayedType(RHSTy), 2217 CastExpr::CK_ArrayToPointerDecay); 2218 RHSTy = RHSExp->getType(); 2219 2220 BaseExpr = RHSExp; 2221 IndexExpr = LHSExp; 2222 ResultType = RHSTy->getAs<PointerType>()->getPointeeType(); 2223 } else { 2224 return ExprError(Diag(LLoc, diag::err_typecheck_subscript_value) 2225 << LHSExp->getSourceRange() << RHSExp->getSourceRange()); 2226 } 2227 // C99 6.5.2.1p1 2228 if (!(IndexExpr->getType()->isIntegerType() && 2229 IndexExpr->getType()->isScalarType()) && !IndexExpr->isTypeDependent()) 2230 return ExprError(Diag(LLoc, diag::err_typecheck_subscript_not_integer) 2231 << IndexExpr->getSourceRange()); 2232 2233 if ((IndexExpr->getType()->isSpecificBuiltinType(BuiltinType::Char_S) || 2234 IndexExpr->getType()->isSpecificBuiltinType(BuiltinType::Char_U)) 2235 && !IndexExpr->isTypeDependent()) 2236 Diag(LLoc, diag::warn_subscript_is_char) << IndexExpr->getSourceRange(); 2237 2238 // C99 6.5.2.1p1: "shall have type "pointer to *object* type". Similarly, 2239 // C++ [expr.sub]p1: The type "T" shall be a completely-defined object 2240 // type. Note that Functions are not objects, and that (in C99 parlance) 2241 // incomplete types are not object types. 2242 if (ResultType->isFunctionType()) { 2243 Diag(BaseExpr->getLocStart(), diag::err_subscript_function_type) 2244 << ResultType << BaseExpr->getSourceRange(); 2245 return ExprError(); 2246 } 2247 2248 if (!ResultType->isDependentType() && 2249 RequireCompleteType(LLoc, ResultType, 2250 PDiag(diag::err_subscript_incomplete_type) 2251 << BaseExpr->getSourceRange())) 2252 return ExprError(); 2253 2254 // Diagnose bad cases where we step over interface counts. 2255 if (ResultType->isObjCInterfaceType() && LangOpts.ObjCNonFragileABI) { 2256 Diag(LLoc, diag::err_subscript_nonfragile_interface) 2257 << ResultType << BaseExpr->getSourceRange(); 2258 return ExprError(); 2259 } 2260 2261 Base.release(); 2262 Idx.release(); 2263 return Owned(new (Context) ArraySubscriptExpr(LHSExp, RHSExp, 2264 ResultType, RLoc)); 2265} 2266 2267QualType Sema:: 2268CheckExtVectorComponent(QualType baseType, SourceLocation OpLoc, 2269 const IdentifierInfo *CompName, 2270 SourceLocation CompLoc) { 2271 // FIXME: Share logic with ExtVectorElementExpr::containsDuplicateElements, 2272 // see FIXME there. 2273 // 2274 // FIXME: This logic can be greatly simplified by splitting it along 2275 // halving/not halving and reworking the component checking. 2276 const ExtVectorType *vecType = baseType->getAs<ExtVectorType>(); 2277 2278 // The vector accessor can't exceed the number of elements. 2279 const char *compStr = CompName->getNameStart(); 2280 2281 // This flag determines whether or not the component is one of the four 2282 // special names that indicate a subset of exactly half the elements are 2283 // to be selected. 2284 bool HalvingSwizzle = false; 2285 2286 // This flag determines whether or not CompName has an 's' char prefix, 2287 // indicating that it is a string of hex values to be used as vector indices. 2288 bool HexSwizzle = *compStr == 's' || *compStr == 'S'; 2289 2290 // Check that we've found one of the special components, or that the component 2291 // names must come from the same set. 2292 if (!strcmp(compStr, "hi") || !strcmp(compStr, "lo") || 2293 !strcmp(compStr, "even") || !strcmp(compStr, "odd")) { 2294 HalvingSwizzle = true; 2295 } else if (vecType->getPointAccessorIdx(*compStr) != -1) { 2296 do 2297 compStr++; 2298 while (*compStr && vecType->getPointAccessorIdx(*compStr) != -1); 2299 } else if (HexSwizzle || vecType->getNumericAccessorIdx(*compStr) != -1) { 2300 do 2301 compStr++; 2302 while (*compStr && vecType->getNumericAccessorIdx(*compStr) != -1); 2303 } 2304 2305 if (!HalvingSwizzle && *compStr) { 2306 // We didn't get to the end of the string. This means the component names 2307 // didn't come from the same set *or* we encountered an illegal name. 2308 Diag(OpLoc, diag::err_ext_vector_component_name_illegal) 2309 << std::string(compStr,compStr+1) << SourceRange(CompLoc); 2310 return QualType(); 2311 } 2312 2313 // Ensure no component accessor exceeds the width of the vector type it 2314 // operates on. 2315 if (!HalvingSwizzle) { 2316 compStr = CompName->getNameStart(); 2317 2318 if (HexSwizzle) 2319 compStr++; 2320 2321 while (*compStr) { 2322 if (!vecType->isAccessorWithinNumElements(*compStr++)) { 2323 Diag(OpLoc, diag::err_ext_vector_component_exceeds_length) 2324 << baseType << SourceRange(CompLoc); 2325 return QualType(); 2326 } 2327 } 2328 } 2329 2330 // The component accessor looks fine - now we need to compute the actual type. 2331 // The vector type is implied by the component accessor. For example, 2332 // vec4.b is a float, vec4.xy is a vec2, vec4.rgb is a vec3, etc. 2333 // vec4.s0 is a float, vec4.s23 is a vec3, etc. 2334 // vec4.hi, vec4.lo, vec4.e, and vec4.o all return vec2. 2335 unsigned CompSize = HalvingSwizzle ? (vecType->getNumElements() + 1) / 2 2336 : CompName->getLength(); 2337 if (HexSwizzle) 2338 CompSize--; 2339 2340 if (CompSize == 1) 2341 return vecType->getElementType(); 2342 2343 QualType VT = Context.getExtVectorType(vecType->getElementType(), CompSize); 2344 // Now look up the TypeDefDecl from the vector type. Without this, 2345 // diagostics look bad. We want extended vector types to appear built-in. 2346 for (unsigned i = 0, E = ExtVectorDecls.size(); i != E; ++i) { 2347 if (ExtVectorDecls[i]->getUnderlyingType() == VT) 2348 return Context.getTypedefType(ExtVectorDecls[i]); 2349 } 2350 return VT; // should never get here (a typedef type should always be found). 2351} 2352 2353static Decl *FindGetterNameDeclFromProtocolList(const ObjCProtocolDecl*PDecl, 2354 IdentifierInfo *Member, 2355 const Selector &Sel, 2356 ASTContext &Context) { 2357 2358 if (ObjCPropertyDecl *PD = PDecl->FindPropertyDeclaration(Member)) 2359 return PD; 2360 if (ObjCMethodDecl *OMD = PDecl->getInstanceMethod(Sel)) 2361 return OMD; 2362 2363 for (ObjCProtocolDecl::protocol_iterator I = PDecl->protocol_begin(), 2364 E = PDecl->protocol_end(); I != E; ++I) { 2365 if (Decl *D = FindGetterNameDeclFromProtocolList(*I, Member, Sel, 2366 Context)) 2367 return D; 2368 } 2369 return 0; 2370} 2371 2372static Decl *FindGetterNameDecl(const ObjCObjectPointerType *QIdTy, 2373 IdentifierInfo *Member, 2374 const Selector &Sel, 2375 ASTContext &Context) { 2376 // Check protocols on qualified interfaces. 2377 Decl *GDecl = 0; 2378 for (ObjCObjectPointerType::qual_iterator I = QIdTy->qual_begin(), 2379 E = QIdTy->qual_end(); I != E; ++I) { 2380 if (ObjCPropertyDecl *PD = (*I)->FindPropertyDeclaration(Member)) { 2381 GDecl = PD; 2382 break; 2383 } 2384 // Also must look for a getter name which uses property syntax. 2385 if (ObjCMethodDecl *OMD = (*I)->getInstanceMethod(Sel)) { 2386 GDecl = OMD; 2387 break; 2388 } 2389 } 2390 if (!GDecl) { 2391 for (ObjCObjectPointerType::qual_iterator I = QIdTy->qual_begin(), 2392 E = QIdTy->qual_end(); I != E; ++I) { 2393 // Search in the protocol-qualifier list of current protocol. 2394 GDecl = FindGetterNameDeclFromProtocolList(*I, Member, Sel, Context); 2395 if (GDecl) 2396 return GDecl; 2397 } 2398 } 2399 return GDecl; 2400} 2401 2402Sema::OwningExprResult 2403Sema::ActOnDependentMemberExpr(ExprArg Base, QualType BaseType, 2404 bool IsArrow, SourceLocation OpLoc, 2405 const CXXScopeSpec &SS, 2406 NamedDecl *FirstQualifierInScope, 2407 DeclarationName Name, SourceLocation NameLoc, 2408 const TemplateArgumentListInfo *TemplateArgs) { 2409 Expr *BaseExpr = Base.takeAs<Expr>(); 2410 2411 // Even in dependent contexts, try to diagnose base expressions with 2412 // obviously wrong types, e.g.: 2413 // 2414 // T* t; 2415 // t.f; 2416 // 2417 // In Obj-C++, however, the above expression is valid, since it could be 2418 // accessing the 'f' property if T is an Obj-C interface. The extra check 2419 // allows this, while still reporting an error if T is a struct pointer. 2420 if (!IsArrow) { 2421 const PointerType *PT = BaseType->getAs<PointerType>(); 2422 if (PT && (!getLangOptions().ObjC1 || 2423 PT->getPointeeType()->isRecordType())) { 2424 assert(BaseExpr && "cannot happen with implicit member accesses"); 2425 Diag(NameLoc, diag::err_typecheck_member_reference_struct_union) 2426 << BaseType << BaseExpr->getSourceRange(); 2427 return ExprError(); 2428 } 2429 } 2430 2431 assert(BaseType->isDependentType() || Name.isDependentName()); 2432 2433 // Get the type being accessed in BaseType. If this is an arrow, the BaseExpr 2434 // must have pointer type, and the accessed type is the pointee. 2435 return Owned(CXXDependentScopeMemberExpr::Create(Context, BaseExpr, BaseType, 2436 IsArrow, OpLoc, 2437 static_cast<NestedNameSpecifier*>(SS.getScopeRep()), 2438 SS.getRange(), 2439 FirstQualifierInScope, 2440 Name, NameLoc, 2441 TemplateArgs)); 2442} 2443 2444/// We know that the given qualified member reference points only to 2445/// declarations which do not belong to the static type of the base 2446/// expression. Diagnose the problem. 2447static void DiagnoseQualifiedMemberReference(Sema &SemaRef, 2448 Expr *BaseExpr, 2449 QualType BaseType, 2450 const CXXScopeSpec &SS, 2451 const LookupResult &R) { 2452 // If this is an implicit member access, use a different set of 2453 // diagnostics. 2454 if (!BaseExpr) 2455 return DiagnoseInstanceReference(SemaRef, SS, R); 2456 2457 // FIXME: this is an exceedingly lame diagnostic for some of the more 2458 // complicated cases here. 2459 DeclContext *DC = R.getRepresentativeDecl()->getDeclContext(); 2460 SemaRef.Diag(R.getNameLoc(), diag::err_not_direct_base_or_virtual) 2461 << SS.getRange() << DC << BaseType; 2462} 2463 2464// Check whether the declarations we found through a nested-name 2465// specifier in a member expression are actually members of the base 2466// type. The restriction here is: 2467// 2468// C++ [expr.ref]p2: 2469// ... In these cases, the id-expression shall name a 2470// member of the class or of one of its base classes. 2471// 2472// So it's perfectly legitimate for the nested-name specifier to name 2473// an unrelated class, and for us to find an overload set including 2474// decls from classes which are not superclasses, as long as the decl 2475// we actually pick through overload resolution is from a superclass. 2476bool Sema::CheckQualifiedMemberReference(Expr *BaseExpr, 2477 QualType BaseType, 2478 const CXXScopeSpec &SS, 2479 const LookupResult &R) { 2480 const RecordType *BaseRT = BaseType->getAs<RecordType>(); 2481 if (!BaseRT) { 2482 // We can't check this yet because the base type is still 2483 // dependent. 2484 assert(BaseType->isDependentType()); 2485 return false; 2486 } 2487 CXXRecordDecl *BaseRecord = cast<CXXRecordDecl>(BaseRT->getDecl()); 2488 2489 for (LookupResult::iterator I = R.begin(), E = R.end(); I != E; ++I) { 2490 // If this is an implicit member reference and we find a 2491 // non-instance member, it's not an error. 2492 if (!BaseExpr && !IsInstanceMember((*I)->getUnderlyingDecl())) 2493 return false; 2494 2495 // Note that we use the DC of the decl, not the underlying decl. 2496 CXXRecordDecl *RecordD = cast<CXXRecordDecl>((*I)->getDeclContext()); 2497 while (RecordD->isAnonymousStructOrUnion()) 2498 RecordD = cast<CXXRecordDecl>(RecordD->getParent()); 2499 2500 llvm::SmallPtrSet<CXXRecordDecl*,4> MemberRecord; 2501 MemberRecord.insert(RecordD->getCanonicalDecl()); 2502 2503 if (!IsProvablyNotDerivedFrom(*this, BaseRecord, MemberRecord)) 2504 return false; 2505 } 2506 2507 DiagnoseQualifiedMemberReference(*this, BaseExpr, BaseType, SS, R); 2508 return true; 2509} 2510 2511static bool 2512LookupMemberExprInRecord(Sema &SemaRef, LookupResult &R, 2513 SourceRange BaseRange, const RecordType *RTy, 2514 SourceLocation OpLoc, const CXXScopeSpec &SS) { 2515 RecordDecl *RDecl = RTy->getDecl(); 2516 if (SemaRef.RequireCompleteType(OpLoc, QualType(RTy, 0), 2517 PDiag(diag::err_typecheck_incomplete_tag) 2518 << BaseRange)) 2519 return true; 2520 2521 DeclContext *DC = RDecl; 2522 if (SS.isSet()) { 2523 // If the member name was a qualified-id, look into the 2524 // nested-name-specifier. 2525 DC = SemaRef.computeDeclContext(SS, false); 2526 2527 if (SemaRef.RequireCompleteDeclContext(SS)) { 2528 SemaRef.Diag(SS.getRange().getEnd(), diag::err_typecheck_incomplete_tag) 2529 << SS.getRange() << DC; 2530 return true; 2531 } 2532 2533 assert(DC && "Cannot handle non-computable dependent contexts in lookup"); 2534 2535 if (!isa<TypeDecl>(DC)) { 2536 SemaRef.Diag(R.getNameLoc(), diag::err_qualified_member_nonclass) 2537 << DC << SS.getRange(); 2538 return true; 2539 } 2540 } 2541 2542 // The record definition is complete, now look up the member. 2543 SemaRef.LookupQualifiedName(R, DC); 2544 2545 if (!R.empty()) 2546 return false; 2547 2548 // We didn't find anything with the given name, so try to correct 2549 // for typos. 2550 DeclarationName Name = R.getLookupName(); 2551 if (SemaRef.CorrectTypo(R, 0, &SS, DC) && 2552 (isa<ValueDecl>(*R.begin()) || isa<FunctionTemplateDecl>(*R.begin()))) { 2553 SemaRef.Diag(R.getNameLoc(), diag::err_no_member_suggest) 2554 << Name << DC << R.getLookupName() << SS.getRange() 2555 << CodeModificationHint::CreateReplacement(R.getNameLoc(), 2556 R.getLookupName().getAsString()); 2557 if (NamedDecl *ND = R.getAsSingle<NamedDecl>()) 2558 SemaRef.Diag(ND->getLocation(), diag::note_previous_decl) 2559 << ND->getDeclName(); 2560 return false; 2561 } else { 2562 R.clear(); 2563 } 2564 2565 return false; 2566} 2567 2568Sema::OwningExprResult 2569Sema::BuildMemberReferenceExpr(ExprArg BaseArg, QualType BaseType, 2570 SourceLocation OpLoc, bool IsArrow, 2571 const CXXScopeSpec &SS, 2572 NamedDecl *FirstQualifierInScope, 2573 DeclarationName Name, SourceLocation NameLoc, 2574 const TemplateArgumentListInfo *TemplateArgs) { 2575 Expr *Base = BaseArg.takeAs<Expr>(); 2576 2577 if (BaseType->isDependentType() || 2578 (SS.isSet() && isDependentScopeSpecifier(SS))) 2579 return ActOnDependentMemberExpr(ExprArg(*this, Base), BaseType, 2580 IsArrow, OpLoc, 2581 SS, FirstQualifierInScope, 2582 Name, NameLoc, 2583 TemplateArgs); 2584 2585 LookupResult R(*this, Name, NameLoc, LookupMemberName); 2586 2587 // Implicit member accesses. 2588 if (!Base) { 2589 QualType RecordTy = BaseType; 2590 if (IsArrow) RecordTy = RecordTy->getAs<PointerType>()->getPointeeType(); 2591 if (LookupMemberExprInRecord(*this, R, SourceRange(), 2592 RecordTy->getAs<RecordType>(), 2593 OpLoc, SS)) 2594 return ExprError(); 2595 2596 // Explicit member accesses. 2597 } else { 2598 OwningExprResult Result = 2599 LookupMemberExpr(R, Base, IsArrow, OpLoc, 2600 SS, /*ObjCImpDecl*/ DeclPtrTy()); 2601 2602 if (Result.isInvalid()) { 2603 Owned(Base); 2604 return ExprError(); 2605 } 2606 2607 if (Result.get()) 2608 return move(Result); 2609 } 2610 2611 return BuildMemberReferenceExpr(ExprArg(*this, Base), BaseType, 2612 OpLoc, IsArrow, SS, FirstQualifierInScope, 2613 R, TemplateArgs); 2614} 2615 2616Sema::OwningExprResult 2617Sema::BuildMemberReferenceExpr(ExprArg Base, QualType BaseExprType, 2618 SourceLocation OpLoc, bool IsArrow, 2619 const CXXScopeSpec &SS, 2620 NamedDecl *FirstQualifierInScope, 2621 LookupResult &R, 2622 const TemplateArgumentListInfo *TemplateArgs) { 2623 Expr *BaseExpr = Base.takeAs<Expr>(); 2624 QualType BaseType = BaseExprType; 2625 if (IsArrow) { 2626 assert(BaseType->isPointerType()); 2627 BaseType = BaseType->getAs<PointerType>()->getPointeeType(); 2628 } 2629 2630 NestedNameSpecifier *Qualifier = 2631 static_cast<NestedNameSpecifier*>(SS.getScopeRep()); 2632 DeclarationName MemberName = R.getLookupName(); 2633 SourceLocation MemberLoc = R.getNameLoc(); 2634 2635 if (R.isAmbiguous()) 2636 return ExprError(); 2637 2638 if (R.empty()) { 2639 // Rederive where we looked up. 2640 DeclContext *DC = (SS.isSet() 2641 ? computeDeclContext(SS, false) 2642 : BaseType->getAs<RecordType>()->getDecl()); 2643 2644 Diag(R.getNameLoc(), diag::err_no_member) 2645 << MemberName << DC 2646 << (BaseExpr ? BaseExpr->getSourceRange() : SourceRange()); 2647 return ExprError(); 2648 } 2649 2650 // Diagnose lookups that find only declarations from a non-base 2651 // type. This is possible for either qualified lookups (which may 2652 // have been qualified with an unrelated type) or implicit member 2653 // expressions (which were found with unqualified lookup and thus 2654 // may have come from an enclosing scope). Note that it's okay for 2655 // lookup to find declarations from a non-base type as long as those 2656 // aren't the ones picked by overload resolution. 2657 if ((SS.isSet() || !BaseExpr || 2658 (isa<CXXThisExpr>(BaseExpr) && 2659 cast<CXXThisExpr>(BaseExpr)->isImplicit())) && 2660 CheckQualifiedMemberReference(BaseExpr, BaseType, SS, R)) 2661 return ExprError(); 2662 2663 // Construct an unresolved result if we in fact got an unresolved 2664 // result. 2665 if (R.isOverloadedResult() || R.isUnresolvableResult()) { 2666 bool Dependent = 2667 BaseExprType->isDependentType() || 2668 R.isUnresolvableResult() || 2669 OverloadExpr::ComputeDependence(R.begin(), R.end(), TemplateArgs); 2670 2671 // Suppress any lookup-related diagnostics; we'll do these when we 2672 // pick a member. 2673 R.suppressDiagnostics(); 2674 2675 UnresolvedMemberExpr *MemExpr 2676 = UnresolvedMemberExpr::Create(Context, Dependent, 2677 R.isUnresolvableResult(), 2678 BaseExpr, BaseExprType, 2679 IsArrow, OpLoc, 2680 Qualifier, SS.getRange(), 2681 MemberName, MemberLoc, 2682 TemplateArgs); 2683 MemExpr->addDecls(R.begin(), R.end()); 2684 2685 return Owned(MemExpr); 2686 } 2687 2688 assert(R.isSingleResult()); 2689 NamedDecl *MemberDecl = R.getFoundDecl(); 2690 2691 // FIXME: diagnose the presence of template arguments now. 2692 2693 // If the decl being referenced had an error, return an error for this 2694 // sub-expr without emitting another error, in order to avoid cascading 2695 // error cases. 2696 if (MemberDecl->isInvalidDecl()) 2697 return ExprError(); 2698 2699 // Handle the implicit-member-access case. 2700 if (!BaseExpr) { 2701 // If this is not an instance member, convert to a non-member access. 2702 if (!IsInstanceMember(MemberDecl)) 2703 return BuildDeclarationNameExpr(SS, R.getNameLoc(), MemberDecl); 2704 2705 SourceLocation Loc = R.getNameLoc(); 2706 if (SS.getRange().isValid()) 2707 Loc = SS.getRange().getBegin(); 2708 BaseExpr = new (Context) CXXThisExpr(Loc, BaseExprType,/*isImplicit=*/true); 2709 } 2710 2711 bool ShouldCheckUse = true; 2712 if (CXXMethodDecl *MD = dyn_cast<CXXMethodDecl>(MemberDecl)) { 2713 // Don't diagnose the use of a virtual member function unless it's 2714 // explicitly qualified. 2715 if (MD->isVirtual() && !SS.isSet()) 2716 ShouldCheckUse = false; 2717 } 2718 2719 // Check the use of this member. 2720 if (ShouldCheckUse && DiagnoseUseOfDecl(MemberDecl, MemberLoc)) { 2721 Owned(BaseExpr); 2722 return ExprError(); 2723 } 2724 2725 if (FieldDecl *FD = dyn_cast<FieldDecl>(MemberDecl)) { 2726 // We may have found a field within an anonymous union or struct 2727 // (C++ [class.union]). 2728 if (cast<RecordDecl>(FD->getDeclContext())->isAnonymousStructOrUnion() && 2729 !BaseType->getAs<RecordType>()->getDecl()->isAnonymousStructOrUnion()) 2730 return BuildAnonymousStructUnionMemberReference(MemberLoc, FD, 2731 BaseExpr, OpLoc); 2732 2733 // Figure out the type of the member; see C99 6.5.2.3p3, C++ [expr.ref] 2734 QualType MemberType = FD->getType(); 2735 if (const ReferenceType *Ref = MemberType->getAs<ReferenceType>()) 2736 MemberType = Ref->getPointeeType(); 2737 else { 2738 Qualifiers BaseQuals = BaseType.getQualifiers(); 2739 BaseQuals.removeObjCGCAttr(); 2740 if (FD->isMutable()) BaseQuals.removeConst(); 2741 2742 Qualifiers MemberQuals 2743 = Context.getCanonicalType(MemberType).getQualifiers(); 2744 2745 Qualifiers Combined = BaseQuals + MemberQuals; 2746 if (Combined != MemberQuals) 2747 MemberType = Context.getQualifiedType(MemberType, Combined); 2748 } 2749 2750 MarkDeclarationReferenced(MemberLoc, FD); 2751 if (PerformObjectMemberConversion(BaseExpr, Qualifier, FD)) 2752 return ExprError(); 2753 return Owned(BuildMemberExpr(Context, BaseExpr, IsArrow, SS, 2754 FD, MemberLoc, MemberType)); 2755 } 2756 2757 if (VarDecl *Var = dyn_cast<VarDecl>(MemberDecl)) { 2758 MarkDeclarationReferenced(MemberLoc, Var); 2759 return Owned(BuildMemberExpr(Context, BaseExpr, IsArrow, SS, 2760 Var, MemberLoc, 2761 Var->getType().getNonReferenceType())); 2762 } 2763 2764 if (FunctionDecl *MemberFn = dyn_cast<FunctionDecl>(MemberDecl)) { 2765 MarkDeclarationReferenced(MemberLoc, MemberDecl); 2766 return Owned(BuildMemberExpr(Context, BaseExpr, IsArrow, SS, 2767 MemberFn, MemberLoc, 2768 MemberFn->getType())); 2769 } 2770 2771 if (EnumConstantDecl *Enum = dyn_cast<EnumConstantDecl>(MemberDecl)) { 2772 MarkDeclarationReferenced(MemberLoc, MemberDecl); 2773 return Owned(BuildMemberExpr(Context, BaseExpr, IsArrow, SS, 2774 Enum, MemberLoc, Enum->getType())); 2775 } 2776 2777 Owned(BaseExpr); 2778 2779 if (isa<TypeDecl>(MemberDecl)) 2780 return ExprError(Diag(MemberLoc,diag::err_typecheck_member_reference_type) 2781 << MemberName << int(IsArrow)); 2782 2783 // We found a declaration kind that we didn't expect. This is a 2784 // generic error message that tells the user that she can't refer 2785 // to this member with '.' or '->'. 2786 return ExprError(Diag(MemberLoc, 2787 diag::err_typecheck_member_reference_unknown) 2788 << MemberName << int(IsArrow)); 2789} 2790 2791/// Look up the given member of the given non-type-dependent 2792/// expression. This can return in one of two ways: 2793/// * If it returns a sentinel null-but-valid result, the caller will 2794/// assume that lookup was performed and the results written into 2795/// the provided structure. It will take over from there. 2796/// * Otherwise, the returned expression will be produced in place of 2797/// an ordinary member expression. 2798/// 2799/// The ObjCImpDecl bit is a gross hack that will need to be properly 2800/// fixed for ObjC++. 2801Sema::OwningExprResult 2802Sema::LookupMemberExpr(LookupResult &R, Expr *&BaseExpr, 2803 bool &IsArrow, SourceLocation OpLoc, 2804 const CXXScopeSpec &SS, 2805 DeclPtrTy ObjCImpDecl) { 2806 assert(BaseExpr && "no base expression"); 2807 2808 // Perform default conversions. 2809 DefaultFunctionArrayConversion(BaseExpr); 2810 2811 QualType BaseType = BaseExpr->getType(); 2812 assert(!BaseType->isDependentType()); 2813 2814 DeclarationName MemberName = R.getLookupName(); 2815 SourceLocation MemberLoc = R.getNameLoc(); 2816 2817 // If the user is trying to apply -> or . to a function pointer 2818 // type, it's probably because they forgot parentheses to call that 2819 // function. Suggest the addition of those parentheses, build the 2820 // call, and continue on. 2821 if (const PointerType *Ptr = BaseType->getAs<PointerType>()) { 2822 if (const FunctionProtoType *Fun 2823 = Ptr->getPointeeType()->getAs<FunctionProtoType>()) { 2824 QualType ResultTy = Fun->getResultType(); 2825 if (Fun->getNumArgs() == 0 && 2826 ((!IsArrow && ResultTy->isRecordType()) || 2827 (IsArrow && ResultTy->isPointerType() && 2828 ResultTy->getAs<PointerType>()->getPointeeType() 2829 ->isRecordType()))) { 2830 SourceLocation Loc = PP.getLocForEndOfToken(BaseExpr->getLocEnd()); 2831 Diag(Loc, diag::err_member_reference_needs_call) 2832 << QualType(Fun, 0) 2833 << CodeModificationHint::CreateInsertion(Loc, "()"); 2834 2835 OwningExprResult NewBase 2836 = ActOnCallExpr(0, ExprArg(*this, BaseExpr), Loc, 2837 MultiExprArg(*this, 0, 0), 0, Loc); 2838 if (NewBase.isInvalid()) 2839 return ExprError(); 2840 2841 BaseExpr = NewBase.takeAs<Expr>(); 2842 DefaultFunctionArrayConversion(BaseExpr); 2843 BaseType = BaseExpr->getType(); 2844 } 2845 } 2846 } 2847 2848 // If this is an Objective-C pseudo-builtin and a definition is provided then 2849 // use that. 2850 if (BaseType->isObjCIdType()) { 2851 if (IsArrow) { 2852 // Handle the following exceptional case PObj->isa. 2853 if (const ObjCObjectPointerType *OPT = 2854 BaseType->getAs<ObjCObjectPointerType>()) { 2855 if (OPT->getPointeeType()->isSpecificBuiltinType(BuiltinType::ObjCId) && 2856 MemberName.getAsIdentifierInfo()->isStr("isa")) 2857 return Owned(new (Context) ObjCIsaExpr(BaseExpr, true, MemberLoc, 2858 Context.getObjCClassType())); 2859 } 2860 } 2861 // We have an 'id' type. Rather than fall through, we check if this 2862 // is a reference to 'isa'. 2863 if (BaseType != Context.ObjCIdRedefinitionType) { 2864 BaseType = Context.ObjCIdRedefinitionType; 2865 ImpCastExprToType(BaseExpr, BaseType, CastExpr::CK_BitCast); 2866 } 2867 } 2868 2869 // If this is an Objective-C pseudo-builtin and a definition is provided then 2870 // use that. 2871 if (Context.isObjCSelType(BaseType)) { 2872 // We have an 'SEL' type. Rather than fall through, we check if this 2873 // is a reference to 'sel_id'. 2874 if (BaseType != Context.ObjCSelRedefinitionType) { 2875 BaseType = Context.ObjCSelRedefinitionType; 2876 ImpCastExprToType(BaseExpr, BaseType, CastExpr::CK_BitCast); 2877 } 2878 } 2879 2880 assert(!BaseType.isNull() && "no type for member expression"); 2881 2882 // Handle properties on ObjC 'Class' types. 2883 if (!IsArrow && BaseType->isObjCClassType()) { 2884 // Also must look for a getter name which uses property syntax. 2885 IdentifierInfo *Member = MemberName.getAsIdentifierInfo(); 2886 Selector Sel = PP.getSelectorTable().getNullarySelector(Member); 2887 if (ObjCMethodDecl *MD = getCurMethodDecl()) { 2888 ObjCInterfaceDecl *IFace = MD->getClassInterface(); 2889 ObjCMethodDecl *Getter; 2890 // FIXME: need to also look locally in the implementation. 2891 if ((Getter = IFace->lookupClassMethod(Sel))) { 2892 // Check the use of this method. 2893 if (DiagnoseUseOfDecl(Getter, MemberLoc)) 2894 return ExprError(); 2895 } 2896 // If we found a getter then this may be a valid dot-reference, we 2897 // will look for the matching setter, in case it is needed. 2898 Selector SetterSel = 2899 SelectorTable::constructSetterName(PP.getIdentifierTable(), 2900 PP.getSelectorTable(), Member); 2901 ObjCMethodDecl *Setter = IFace->lookupClassMethod(SetterSel); 2902 if (!Setter) { 2903 // If this reference is in an @implementation, also check for 'private' 2904 // methods. 2905 Setter = IFace->lookupPrivateInstanceMethod(SetterSel); 2906 } 2907 // Look through local category implementations associated with the class. 2908 if (!Setter) 2909 Setter = IFace->getCategoryClassMethod(SetterSel); 2910 2911 if (Setter && DiagnoseUseOfDecl(Setter, MemberLoc)) 2912 return ExprError(); 2913 2914 if (Getter || Setter) { 2915 QualType PType; 2916 2917 if (Getter) 2918 PType = Getter->getResultType(); 2919 else 2920 // Get the expression type from Setter's incoming parameter. 2921 PType = (*(Setter->param_end() -1))->getType(); 2922 // FIXME: we must check that the setter has property type. 2923 return Owned(new (Context) ObjCImplicitSetterGetterRefExpr(Getter, 2924 PType, 2925 Setter, MemberLoc, BaseExpr)); 2926 } 2927 return ExprError(Diag(MemberLoc, diag::err_property_not_found) 2928 << MemberName << BaseType); 2929 } 2930 } 2931 2932 if (BaseType->isObjCClassType() && 2933 BaseType != Context.ObjCClassRedefinitionType) { 2934 BaseType = Context.ObjCClassRedefinitionType; 2935 ImpCastExprToType(BaseExpr, BaseType, CastExpr::CK_BitCast); 2936 } 2937 2938 if (IsArrow) { 2939 if (const PointerType *PT = BaseType->getAs<PointerType>()) 2940 BaseType = PT->getPointeeType(); 2941 else if (BaseType->isObjCObjectPointerType()) 2942 ; 2943 else if (BaseType->isRecordType()) { 2944 // Recover from arrow accesses to records, e.g.: 2945 // struct MyRecord foo; 2946 // foo->bar 2947 // This is actually well-formed in C++ if MyRecord has an 2948 // overloaded operator->, but that should have been dealt with 2949 // by now. 2950 Diag(OpLoc, diag::err_typecheck_member_reference_suggestion) 2951 << BaseType << int(IsArrow) << BaseExpr->getSourceRange() 2952 << CodeModificationHint::CreateReplacement(OpLoc, "."); 2953 IsArrow = false; 2954 } else { 2955 Diag(MemberLoc, diag::err_typecheck_member_reference_arrow) 2956 << BaseType << BaseExpr->getSourceRange(); 2957 return ExprError(); 2958 } 2959 } else { 2960 // Recover from dot accesses to pointers, e.g.: 2961 // type *foo; 2962 // foo.bar 2963 // This is actually well-formed in two cases: 2964 // - 'type' is an Objective C type 2965 // - 'bar' is a pseudo-destructor name which happens to refer to 2966 // the appropriate pointer type 2967 if (MemberName.getNameKind() != DeclarationName::CXXDestructorName) { 2968 const PointerType *PT = BaseType->getAs<PointerType>(); 2969 if (PT && PT->getPointeeType()->isRecordType()) { 2970 Diag(OpLoc, diag::err_typecheck_member_reference_suggestion) 2971 << BaseType << int(IsArrow) << BaseExpr->getSourceRange() 2972 << CodeModificationHint::CreateReplacement(OpLoc, "->"); 2973 BaseType = PT->getPointeeType(); 2974 IsArrow = true; 2975 } 2976 } 2977 } 2978 2979 // Handle field access to simple records. This also handles access 2980 // to fields of the ObjC 'id' struct. 2981 if (const RecordType *RTy = BaseType->getAs<RecordType>()) { 2982 if (LookupMemberExprInRecord(*this, R, BaseExpr->getSourceRange(), 2983 RTy, OpLoc, SS)) 2984 return ExprError(); 2985 return Owned((Expr*) 0); 2986 } 2987 2988 // Handle access to Objective-C instance variables, such as "Obj->ivar" and 2989 // (*Obj).ivar. 2990 if ((IsArrow && BaseType->isObjCObjectPointerType()) || 2991 (!IsArrow && BaseType->isObjCInterfaceType())) { 2992 const ObjCObjectPointerType *OPT = BaseType->getAs<ObjCObjectPointerType>(); 2993 const ObjCInterfaceType *IFaceT = 2994 OPT ? OPT->getInterfaceType() : BaseType->getAs<ObjCInterfaceType>(); 2995 if (IFaceT) { 2996 IdentifierInfo *Member = MemberName.getAsIdentifierInfo(); 2997 2998 ObjCInterfaceDecl *IDecl = IFaceT->getDecl(); 2999 ObjCInterfaceDecl *ClassDeclared; 3000 ObjCIvarDecl *IV = IDecl->lookupInstanceVariable(Member, ClassDeclared); 3001 3002 if (!IV) { 3003 // Attempt to correct for typos in ivar names. 3004 LookupResult Res(*this, R.getLookupName(), R.getNameLoc(), 3005 LookupMemberName); 3006 if (CorrectTypo(Res, 0, 0, IDecl) && 3007 (IV = Res.getAsSingle<ObjCIvarDecl>())) { 3008 Diag(R.getNameLoc(), 3009 diag::err_typecheck_member_reference_ivar_suggest) 3010 << IDecl->getDeclName() << MemberName << IV->getDeclName() 3011 << CodeModificationHint::CreateReplacement(R.getNameLoc(), 3012 IV->getNameAsString()); 3013 Diag(IV->getLocation(), diag::note_previous_decl) 3014 << IV->getDeclName(); 3015 } 3016 } 3017 3018 if (IV) { 3019 // If the decl being referenced had an error, return an error for this 3020 // sub-expr without emitting another error, in order to avoid cascading 3021 // error cases. 3022 if (IV->isInvalidDecl()) 3023 return ExprError(); 3024 3025 // Check whether we can reference this field. 3026 if (DiagnoseUseOfDecl(IV, MemberLoc)) 3027 return ExprError(); 3028 if (IV->getAccessControl() != ObjCIvarDecl::Public && 3029 IV->getAccessControl() != ObjCIvarDecl::Package) { 3030 ObjCInterfaceDecl *ClassOfMethodDecl = 0; 3031 if (ObjCMethodDecl *MD = getCurMethodDecl()) 3032 ClassOfMethodDecl = MD->getClassInterface(); 3033 else if (ObjCImpDecl && getCurFunctionDecl()) { 3034 // Case of a c-function declared inside an objc implementation. 3035 // FIXME: For a c-style function nested inside an objc implementation 3036 // class, there is no implementation context available, so we pass 3037 // down the context as argument to this routine. Ideally, this context 3038 // need be passed down in the AST node and somehow calculated from the 3039 // AST for a function decl. 3040 Decl *ImplDecl = ObjCImpDecl.getAs<Decl>(); 3041 if (ObjCImplementationDecl *IMPD = 3042 dyn_cast<ObjCImplementationDecl>(ImplDecl)) 3043 ClassOfMethodDecl = IMPD->getClassInterface(); 3044 else if (ObjCCategoryImplDecl* CatImplClass = 3045 dyn_cast<ObjCCategoryImplDecl>(ImplDecl)) 3046 ClassOfMethodDecl = CatImplClass->getClassInterface(); 3047 } 3048 3049 if (IV->getAccessControl() == ObjCIvarDecl::Private) { 3050 if (ClassDeclared != IDecl || 3051 ClassOfMethodDecl != ClassDeclared) 3052 Diag(MemberLoc, diag::error_private_ivar_access) 3053 << IV->getDeclName(); 3054 } else if (!IDecl->isSuperClassOf(ClassOfMethodDecl)) 3055 // @protected 3056 Diag(MemberLoc, diag::error_protected_ivar_access) 3057 << IV->getDeclName(); 3058 } 3059 3060 return Owned(new (Context) ObjCIvarRefExpr(IV, IV->getType(), 3061 MemberLoc, BaseExpr, 3062 IsArrow)); 3063 } 3064 return ExprError(Diag(MemberLoc, diag::err_typecheck_member_reference_ivar) 3065 << IDecl->getDeclName() << MemberName 3066 << BaseExpr->getSourceRange()); 3067 } 3068 } 3069 // Handle properties on 'id' and qualified "id". 3070 if (!IsArrow && (BaseType->isObjCIdType() || 3071 BaseType->isObjCQualifiedIdType())) { 3072 const ObjCObjectPointerType *QIdTy = BaseType->getAs<ObjCObjectPointerType>(); 3073 IdentifierInfo *Member = MemberName.getAsIdentifierInfo(); 3074 3075 // Check protocols on qualified interfaces. 3076 Selector Sel = PP.getSelectorTable().getNullarySelector(Member); 3077 if (Decl *PMDecl = FindGetterNameDecl(QIdTy, Member, Sel, Context)) { 3078 if (ObjCPropertyDecl *PD = dyn_cast<ObjCPropertyDecl>(PMDecl)) { 3079 // Check the use of this declaration 3080 if (DiagnoseUseOfDecl(PD, MemberLoc)) 3081 return ExprError(); 3082 3083 return Owned(new (Context) ObjCPropertyRefExpr(PD, PD->getType(), 3084 MemberLoc, BaseExpr)); 3085 } 3086 if (ObjCMethodDecl *OMD = dyn_cast<ObjCMethodDecl>(PMDecl)) { 3087 // Check the use of this method. 3088 if (DiagnoseUseOfDecl(OMD, MemberLoc)) 3089 return ExprError(); 3090 3091 return Owned(new (Context) ObjCMessageExpr(Context, BaseExpr, Sel, 3092 OMD->getResultType(), 3093 OMD, OpLoc, MemberLoc, 3094 NULL, 0)); 3095 } 3096 } 3097 3098 return ExprError(Diag(MemberLoc, diag::err_property_not_found) 3099 << MemberName << BaseType); 3100 } 3101 // Handle Objective-C property access, which is "Obj.property" where Obj is a 3102 // pointer to a (potentially qualified) interface type. 3103 const ObjCObjectPointerType *OPT; 3104 if (!IsArrow && (OPT = BaseType->getAsObjCInterfacePointerType())) { 3105 const ObjCInterfaceType *IFaceT = OPT->getInterfaceType(); 3106 ObjCInterfaceDecl *IFace = IFaceT->getDecl(); 3107 IdentifierInfo *Member = MemberName.getAsIdentifierInfo(); 3108 3109 // Search for a declared property first. 3110 if (ObjCPropertyDecl *PD = IFace->FindPropertyDeclaration(Member)) { 3111 // Check whether we can reference this property. 3112 if (DiagnoseUseOfDecl(PD, MemberLoc)) 3113 return ExprError(); 3114 QualType ResTy = PD->getType(); 3115 Selector Sel = PP.getSelectorTable().getNullarySelector(Member); 3116 ObjCMethodDecl *Getter = IFace->lookupInstanceMethod(Sel); 3117 if (DiagnosePropertyAccessorMismatch(PD, Getter, MemberLoc)) 3118 ResTy = Getter->getResultType(); 3119 return Owned(new (Context) ObjCPropertyRefExpr(PD, ResTy, 3120 MemberLoc, BaseExpr)); 3121 } 3122 // Check protocols on qualified interfaces. 3123 for (ObjCObjectPointerType::qual_iterator I = OPT->qual_begin(), 3124 E = OPT->qual_end(); I != E; ++I) 3125 if (ObjCPropertyDecl *PD = (*I)->FindPropertyDeclaration(Member)) { 3126 // Check whether we can reference this property. 3127 if (DiagnoseUseOfDecl(PD, MemberLoc)) 3128 return ExprError(); 3129 3130 return Owned(new (Context) ObjCPropertyRefExpr(PD, PD->getType(), 3131 MemberLoc, BaseExpr)); 3132 } 3133 // If that failed, look for an "implicit" property by seeing if the nullary 3134 // selector is implemented. 3135 3136 // FIXME: The logic for looking up nullary and unary selectors should be 3137 // shared with the code in ActOnInstanceMessage. 3138 3139 Selector Sel = PP.getSelectorTable().getNullarySelector(Member); 3140 ObjCMethodDecl *Getter = IFace->lookupInstanceMethod(Sel); 3141 3142 // If this reference is in an @implementation, check for 'private' methods. 3143 if (!Getter) 3144 Getter = IFace->lookupPrivateInstanceMethod(Sel); 3145 3146 // Look through local category implementations associated with the class. 3147 if (!Getter) 3148 Getter = IFace->getCategoryInstanceMethod(Sel); 3149 if (Getter) { 3150 // Check if we can reference this property. 3151 if (DiagnoseUseOfDecl(Getter, MemberLoc)) 3152 return ExprError(); 3153 } 3154 // If we found a getter then this may be a valid dot-reference, we 3155 // will look for the matching setter, in case it is needed. 3156 Selector SetterSel = 3157 SelectorTable::constructSetterName(PP.getIdentifierTable(), 3158 PP.getSelectorTable(), Member); 3159 ObjCMethodDecl *Setter = IFace->lookupInstanceMethod(SetterSel); 3160 if (!Setter) { 3161 // If this reference is in an @implementation, also check for 'private' 3162 // methods. 3163 Setter = IFace->lookupPrivateInstanceMethod(SetterSel); 3164 } 3165 // Look through local category implementations associated with the class. 3166 if (!Setter) 3167 Setter = IFace->getCategoryInstanceMethod(SetterSel); 3168 3169 if (Setter && DiagnoseUseOfDecl(Setter, MemberLoc)) 3170 return ExprError(); 3171 3172 if (Getter) { 3173 QualType PType; 3174 PType = Getter->getResultType(); 3175 return Owned(new (Context) ObjCImplicitSetterGetterRefExpr(Getter, PType, 3176 Setter, MemberLoc, BaseExpr)); 3177 } 3178 3179 // Attempt to correct for typos in property names. 3180 LookupResult Res(*this, R.getLookupName(), R.getNameLoc(), 3181 LookupOrdinaryName); 3182 if (CorrectTypo(Res, 0, 0, IFace, false, OPT) && 3183 Res.getAsSingle<ObjCPropertyDecl>()) { 3184 Diag(R.getNameLoc(), diag::err_property_not_found_suggest) 3185 << MemberName << BaseType << Res.getLookupName() 3186 << CodeModificationHint::CreateReplacement(R.getNameLoc(), 3187 Res.getLookupName().getAsString()); 3188 ObjCPropertyDecl *Property = Res.getAsSingle<ObjCPropertyDecl>(); 3189 Diag(Property->getLocation(), diag::note_previous_decl) 3190 << Property->getDeclName(); 3191 3192 return LookupMemberExpr(Res, BaseExpr, IsArrow, OpLoc, SS, 3193 ObjCImpDecl); 3194 } 3195 Diag(MemberLoc, diag::err_property_not_found) 3196 << MemberName << BaseType; 3197 if (Setter && !Getter) 3198 Diag(Setter->getLocation(), diag::note_getter_unavailable) 3199 << MemberName << BaseExpr->getSourceRange(); 3200 return ExprError(); 3201 } 3202 3203 // Handle the following exceptional case (*Obj).isa. 3204 if (!IsArrow && 3205 BaseType->isSpecificBuiltinType(BuiltinType::ObjCId) && 3206 MemberName.getAsIdentifierInfo()->isStr("isa")) 3207 return Owned(new (Context) ObjCIsaExpr(BaseExpr, false, MemberLoc, 3208 Context.getObjCClassType())); 3209 3210 // Handle 'field access' to vectors, such as 'V.xx'. 3211 if (BaseType->isExtVectorType()) { 3212 IdentifierInfo *Member = MemberName.getAsIdentifierInfo(); 3213 QualType ret = CheckExtVectorComponent(BaseType, OpLoc, Member, MemberLoc); 3214 if (ret.isNull()) 3215 return ExprError(); 3216 return Owned(new (Context) ExtVectorElementExpr(ret, BaseExpr, *Member, 3217 MemberLoc)); 3218 } 3219 3220 Diag(MemberLoc, diag::err_typecheck_member_reference_struct_union) 3221 << BaseType << BaseExpr->getSourceRange(); 3222 3223 return ExprError(); 3224} 3225 3226/// The main callback when the parser finds something like 3227/// expression . [nested-name-specifier] identifier 3228/// expression -> [nested-name-specifier] identifier 3229/// where 'identifier' encompasses a fairly broad spectrum of 3230/// possibilities, including destructor and operator references. 3231/// 3232/// \param OpKind either tok::arrow or tok::period 3233/// \param HasTrailingLParen whether the next token is '(', which 3234/// is used to diagnose mis-uses of special members that can 3235/// only be called 3236/// \param ObjCImpDecl the current ObjC @implementation decl; 3237/// this is an ugly hack around the fact that ObjC @implementations 3238/// aren't properly put in the context chain 3239Sema::OwningExprResult Sema::ActOnMemberAccessExpr(Scope *S, ExprArg BaseArg, 3240 SourceLocation OpLoc, 3241 tok::TokenKind OpKind, 3242 const CXXScopeSpec &SS, 3243 UnqualifiedId &Id, 3244 DeclPtrTy ObjCImpDecl, 3245 bool HasTrailingLParen) { 3246 if (SS.isSet() && SS.isInvalid()) 3247 return ExprError(); 3248 3249 TemplateArgumentListInfo TemplateArgsBuffer; 3250 3251 // Decompose the name into its component parts. 3252 DeclarationName Name; 3253 SourceLocation NameLoc; 3254 const TemplateArgumentListInfo *TemplateArgs; 3255 DecomposeUnqualifiedId(*this, Id, TemplateArgsBuffer, 3256 Name, NameLoc, TemplateArgs); 3257 3258 bool IsArrow = (OpKind == tok::arrow); 3259 3260 NamedDecl *FirstQualifierInScope 3261 = (!SS.isSet() ? 0 : FindFirstQualifierInScope(S, 3262 static_cast<NestedNameSpecifier*>(SS.getScopeRep()))); 3263 3264 // This is a postfix expression, so get rid of ParenListExprs. 3265 BaseArg = MaybeConvertParenListExprToParenExpr(S, move(BaseArg)); 3266 3267 Expr *Base = BaseArg.takeAs<Expr>(); 3268 OwningExprResult Result(*this); 3269 if (Base->getType()->isDependentType() || Name.isDependentName()) { 3270 Result = ActOnDependentMemberExpr(ExprArg(*this, Base), Base->getType(), 3271 IsArrow, OpLoc, 3272 SS, FirstQualifierInScope, 3273 Name, NameLoc, 3274 TemplateArgs); 3275 } else { 3276 LookupResult R(*this, Name, NameLoc, LookupMemberName); 3277 if (TemplateArgs) { 3278 // Re-use the lookup done for the template name. 3279 DecomposeTemplateName(R, Id); 3280 } else { 3281 Result = LookupMemberExpr(R, Base, IsArrow, OpLoc, 3282 SS, ObjCImpDecl); 3283 3284 if (Result.isInvalid()) { 3285 Owned(Base); 3286 return ExprError(); 3287 } 3288 3289 if (Result.get()) { 3290 // The only way a reference to a destructor can be used is to 3291 // immediately call it, which falls into this case. If the 3292 // next token is not a '(', produce a diagnostic and build the 3293 // call now. 3294 if (!HasTrailingLParen && 3295 Id.getKind() == UnqualifiedId::IK_DestructorName) 3296 return DiagnoseDtorReference(NameLoc, move(Result)); 3297 3298 return move(Result); 3299 } 3300 } 3301 3302 Result = BuildMemberReferenceExpr(ExprArg(*this, Base), Base->getType(), 3303 OpLoc, IsArrow, SS, FirstQualifierInScope, 3304 R, TemplateArgs); 3305 } 3306 3307 return move(Result); 3308} 3309 3310Sema::OwningExprResult Sema::BuildCXXDefaultArgExpr(SourceLocation CallLoc, 3311 FunctionDecl *FD, 3312 ParmVarDecl *Param) { 3313 if (Param->hasUnparsedDefaultArg()) { 3314 Diag (CallLoc, 3315 diag::err_use_of_default_argument_to_function_declared_later) << 3316 FD << cast<CXXRecordDecl>(FD->getDeclContext())->getDeclName(); 3317 Diag(UnparsedDefaultArgLocs[Param], 3318 diag::note_default_argument_declared_here); 3319 } else { 3320 if (Param->hasUninstantiatedDefaultArg()) { 3321 Expr *UninstExpr = Param->getUninstantiatedDefaultArg(); 3322 3323 // Instantiate the expression. 3324 MultiLevelTemplateArgumentList ArgList 3325 = getTemplateInstantiationArgs(FD, 0, /*RelativeToPrimary=*/true); 3326 3327 InstantiatingTemplate Inst(*this, CallLoc, Param, 3328 ArgList.getInnermost().getFlatArgumentList(), 3329 ArgList.getInnermost().flat_size()); 3330 3331 OwningExprResult Result = SubstExpr(UninstExpr, ArgList); 3332 if (Result.isInvalid()) 3333 return ExprError(); 3334 3335 // Check the expression as an initializer for the parameter. 3336 InitializedEntity Entity 3337 = InitializedEntity::InitializeParameter(Param); 3338 InitializationKind Kind 3339 = InitializationKind::CreateCopy(Param->getLocation(), 3340 /*FIXME:EqualLoc*/UninstExpr->getSourceRange().getBegin()); 3341 Expr *ResultE = Result.takeAs<Expr>(); 3342 3343 InitializationSequence InitSeq(*this, Entity, Kind, &ResultE, 1); 3344 Result = InitSeq.Perform(*this, Entity, Kind, 3345 MultiExprArg(*this, (void**)&ResultE, 1)); 3346 if (Result.isInvalid()) 3347 return ExprError(); 3348 3349 // Build the default argument expression. 3350 return Owned(CXXDefaultArgExpr::Create(Context, CallLoc, Param, 3351 Result.takeAs<Expr>())); 3352 } 3353 3354 // If the default expression creates temporaries, we need to 3355 // push them to the current stack of expression temporaries so they'll 3356 // be properly destroyed. 3357 // FIXME: We should really be rebuilding the default argument with new 3358 // bound temporaries; see the comment in PR5810. 3359 for (unsigned i = 0, e = Param->getNumDefaultArgTemporaries(); i != e; ++i) 3360 ExprTemporaries.push_back(Param->getDefaultArgTemporary(i)); 3361 } 3362 3363 // We already type-checked the argument, so we know it works. 3364 return Owned(CXXDefaultArgExpr::Create(Context, CallLoc, Param)); 3365} 3366 3367/// ConvertArgumentsForCall - Converts the arguments specified in 3368/// Args/NumArgs to the parameter types of the function FDecl with 3369/// function prototype Proto. Call is the call expression itself, and 3370/// Fn is the function expression. For a C++ member function, this 3371/// routine does not attempt to convert the object argument. Returns 3372/// true if the call is ill-formed. 3373bool 3374Sema::ConvertArgumentsForCall(CallExpr *Call, Expr *Fn, 3375 FunctionDecl *FDecl, 3376 const FunctionProtoType *Proto, 3377 Expr **Args, unsigned NumArgs, 3378 SourceLocation RParenLoc) { 3379 // C99 6.5.2.2p7 - the arguments are implicitly converted, as if by 3380 // assignment, to the types of the corresponding parameter, ... 3381 unsigned NumArgsInProto = Proto->getNumArgs(); 3382 bool Invalid = false; 3383 3384 // If too few arguments are available (and we don't have default 3385 // arguments for the remaining parameters), don't make the call. 3386 if (NumArgs < NumArgsInProto) { 3387 if (!FDecl || NumArgs < FDecl->getMinRequiredArguments()) 3388 return Diag(RParenLoc, diag::err_typecheck_call_too_few_args) 3389 << Fn->getType()->isBlockPointerType() << Fn->getSourceRange(); 3390 Call->setNumArgs(Context, NumArgsInProto); 3391 } 3392 3393 // If too many are passed and not variadic, error on the extras and drop 3394 // them. 3395 if (NumArgs > NumArgsInProto) { 3396 if (!Proto->isVariadic()) { 3397 Diag(Args[NumArgsInProto]->getLocStart(), 3398 diag::err_typecheck_call_too_many_args) 3399 << Fn->getType()->isBlockPointerType() << Fn->getSourceRange() 3400 << SourceRange(Args[NumArgsInProto]->getLocStart(), 3401 Args[NumArgs-1]->getLocEnd()); 3402 // This deletes the extra arguments. 3403 Call->setNumArgs(Context, NumArgsInProto); 3404 return true; 3405 } 3406 } 3407 llvm::SmallVector<Expr *, 8> AllArgs; 3408 VariadicCallType CallType = 3409 Proto->isVariadic() ? VariadicFunction : VariadicDoesNotApply; 3410 if (Fn->getType()->isBlockPointerType()) 3411 CallType = VariadicBlock; // Block 3412 else if (isa<MemberExpr>(Fn)) 3413 CallType = VariadicMethod; 3414 Invalid = GatherArgumentsForCall(Call->getSourceRange().getBegin(), FDecl, 3415 Proto, 0, Args, NumArgs, AllArgs, CallType); 3416 if (Invalid) 3417 return true; 3418 unsigned TotalNumArgs = AllArgs.size(); 3419 for (unsigned i = 0; i < TotalNumArgs; ++i) 3420 Call->setArg(i, AllArgs[i]); 3421 3422 return false; 3423} 3424 3425bool Sema::GatherArgumentsForCall(SourceLocation CallLoc, 3426 FunctionDecl *FDecl, 3427 const FunctionProtoType *Proto, 3428 unsigned FirstProtoArg, 3429 Expr **Args, unsigned NumArgs, 3430 llvm::SmallVector<Expr *, 8> &AllArgs, 3431 VariadicCallType CallType) { 3432 unsigned NumArgsInProto = Proto->getNumArgs(); 3433 unsigned NumArgsToCheck = NumArgs; 3434 bool Invalid = false; 3435 if (NumArgs != NumArgsInProto) 3436 // Use default arguments for missing arguments 3437 NumArgsToCheck = NumArgsInProto; 3438 unsigned ArgIx = 0; 3439 // Continue to check argument types (even if we have too few/many args). 3440 for (unsigned i = FirstProtoArg; i != NumArgsToCheck; i++) { 3441 QualType ProtoArgType = Proto->getArgType(i); 3442 3443 Expr *Arg; 3444 if (ArgIx < NumArgs) { 3445 Arg = Args[ArgIx++]; 3446 3447 if (RequireCompleteType(Arg->getSourceRange().getBegin(), 3448 ProtoArgType, 3449 PDiag(diag::err_call_incomplete_argument) 3450 << Arg->getSourceRange())) 3451 return true; 3452 3453 // Pass the argument 3454 ParmVarDecl *Param = 0; 3455 if (FDecl && i < FDecl->getNumParams()) 3456 Param = FDecl->getParamDecl(i); 3457 3458 3459 InitializedEntity Entity = 3460 Param? InitializedEntity::InitializeParameter(Param) 3461 : InitializedEntity::InitializeParameter(ProtoArgType); 3462 OwningExprResult ArgE = PerformCopyInitialization(Entity, 3463 SourceLocation(), 3464 Owned(Arg)); 3465 if (ArgE.isInvalid()) 3466 return true; 3467 3468 Arg = ArgE.takeAs<Expr>(); 3469 } else { 3470 ParmVarDecl *Param = FDecl->getParamDecl(i); 3471 3472 OwningExprResult ArgExpr = 3473 BuildCXXDefaultArgExpr(CallLoc, FDecl, Param); 3474 if (ArgExpr.isInvalid()) 3475 return true; 3476 3477 Arg = ArgExpr.takeAs<Expr>(); 3478 } 3479 AllArgs.push_back(Arg); 3480 } 3481 3482 // If this is a variadic call, handle args passed through "...". 3483 if (CallType != VariadicDoesNotApply) { 3484 // Promote the arguments (C99 6.5.2.2p7). 3485 for (unsigned i = ArgIx; i < NumArgs; i++) { 3486 Expr *Arg = Args[i]; 3487 Invalid |= DefaultVariadicArgumentPromotion(Arg, CallType); 3488 AllArgs.push_back(Arg); 3489 } 3490 } 3491 return Invalid; 3492} 3493 3494/// ActOnCallExpr - Handle a call to Fn with the specified array of arguments. 3495/// This provides the location of the left/right parens and a list of comma 3496/// locations. 3497Action::OwningExprResult 3498Sema::ActOnCallExpr(Scope *S, ExprArg fn, SourceLocation LParenLoc, 3499 MultiExprArg args, 3500 SourceLocation *CommaLocs, SourceLocation RParenLoc) { 3501 unsigned NumArgs = args.size(); 3502 3503 // Since this might be a postfix expression, get rid of ParenListExprs. 3504 fn = MaybeConvertParenListExprToParenExpr(S, move(fn)); 3505 3506 Expr *Fn = fn.takeAs<Expr>(); 3507 Expr **Args = reinterpret_cast<Expr**>(args.release()); 3508 assert(Fn && "no function call expression"); 3509 3510 if (getLangOptions().CPlusPlus) { 3511 // If this is a pseudo-destructor expression, build the call immediately. 3512 if (isa<CXXPseudoDestructorExpr>(Fn)) { 3513 if (NumArgs > 0) { 3514 // Pseudo-destructor calls should not have any arguments. 3515 Diag(Fn->getLocStart(), diag::err_pseudo_dtor_call_with_args) 3516 << CodeModificationHint::CreateRemoval( 3517 SourceRange(Args[0]->getLocStart(), 3518 Args[NumArgs-1]->getLocEnd())); 3519 3520 for (unsigned I = 0; I != NumArgs; ++I) 3521 Args[I]->Destroy(Context); 3522 3523 NumArgs = 0; 3524 } 3525 3526 return Owned(new (Context) CallExpr(Context, Fn, 0, 0, Context.VoidTy, 3527 RParenLoc)); 3528 } 3529 3530 // Determine whether this is a dependent call inside a C++ template, 3531 // in which case we won't do any semantic analysis now. 3532 // FIXME: Will need to cache the results of name lookup (including ADL) in 3533 // Fn. 3534 bool Dependent = false; 3535 if (Fn->isTypeDependent()) 3536 Dependent = true; 3537 else if (Expr::hasAnyTypeDependentArguments(Args, NumArgs)) 3538 Dependent = true; 3539 3540 if (Dependent) 3541 return Owned(new (Context) CallExpr(Context, Fn, Args, NumArgs, 3542 Context.DependentTy, RParenLoc)); 3543 3544 // Determine whether this is a call to an object (C++ [over.call.object]). 3545 if (Fn->getType()->isRecordType()) 3546 return Owned(BuildCallToObjectOfClassType(S, Fn, LParenLoc, Args, NumArgs, 3547 CommaLocs, RParenLoc)); 3548 3549 Expr *NakedFn = Fn->IgnoreParens(); 3550 3551 // Determine whether this is a call to an unresolved member function. 3552 if (UnresolvedMemberExpr *MemE = dyn_cast<UnresolvedMemberExpr>(NakedFn)) { 3553 // If lookup was unresolved but not dependent (i.e. didn't find 3554 // an unresolved using declaration), it has to be an overloaded 3555 // function set, which means it must contain either multiple 3556 // declarations (all methods or method templates) or a single 3557 // method template. 3558 assert((MemE->getNumDecls() > 1) || 3559 isa<FunctionTemplateDecl>(*MemE->decls_begin())); 3560 (void)MemE; 3561 3562 return BuildCallToMemberFunction(S, Fn, LParenLoc, Args, NumArgs, 3563 CommaLocs, RParenLoc); 3564 } 3565 3566 // Determine whether this is a call to a member function. 3567 if (MemberExpr *MemExpr = dyn_cast<MemberExpr>(NakedFn)) { 3568 NamedDecl *MemDecl = MemExpr->getMemberDecl(); 3569 if (isa<CXXMethodDecl>(MemDecl)) 3570 return BuildCallToMemberFunction(S, Fn, LParenLoc, Args, NumArgs, 3571 CommaLocs, RParenLoc); 3572 } 3573 3574 // Determine whether this is a call to a pointer-to-member function. 3575 if (BinaryOperator *BO = dyn_cast<BinaryOperator>(NakedFn)) { 3576 if (BO->getOpcode() == BinaryOperator::PtrMemD || 3577 BO->getOpcode() == BinaryOperator::PtrMemI) { 3578 if (const FunctionProtoType *FPT = 3579 dyn_cast<FunctionProtoType>(BO->getType())) { 3580 QualType ResultTy = FPT->getResultType().getNonReferenceType(); 3581 3582 ExprOwningPtr<CXXMemberCallExpr> 3583 TheCall(this, new (Context) CXXMemberCallExpr(Context, BO, Args, 3584 NumArgs, ResultTy, 3585 RParenLoc)); 3586 3587 if (CheckCallReturnType(FPT->getResultType(), 3588 BO->getRHS()->getSourceRange().getBegin(), 3589 TheCall.get(), 0)) 3590 return ExprError(); 3591 3592 if (ConvertArgumentsForCall(&*TheCall, BO, 0, FPT, Args, NumArgs, 3593 RParenLoc)) 3594 return ExprError(); 3595 3596 return Owned(MaybeBindToTemporary(TheCall.release()).release()); 3597 } 3598 return ExprError(Diag(Fn->getLocStart(), 3599 diag::err_typecheck_call_not_function) 3600 << Fn->getType() << Fn->getSourceRange()); 3601 } 3602 } 3603 } 3604 3605 // If we're directly calling a function, get the appropriate declaration. 3606 // Also, in C++, keep track of whether we should perform argument-dependent 3607 // lookup and whether there were any explicitly-specified template arguments. 3608 3609 Expr *NakedFn = Fn->IgnoreParens(); 3610 if (isa<UnresolvedLookupExpr>(NakedFn)) { 3611 UnresolvedLookupExpr *ULE = cast<UnresolvedLookupExpr>(NakedFn); 3612 return BuildOverloadedCallExpr(Fn, ULE, LParenLoc, Args, NumArgs, 3613 CommaLocs, RParenLoc); 3614 } 3615 3616 NamedDecl *NDecl = 0; 3617 if (isa<DeclRefExpr>(NakedFn)) 3618 NDecl = cast<DeclRefExpr>(NakedFn)->getDecl(); 3619 3620 return BuildResolvedCallExpr(Fn, NDecl, LParenLoc, Args, NumArgs, RParenLoc); 3621} 3622 3623/// BuildResolvedCallExpr - Build a call to a resolved expression, 3624/// i.e. an expression not of \p OverloadTy. The expression should 3625/// unary-convert to an expression of function-pointer or 3626/// block-pointer type. 3627/// 3628/// \param NDecl the declaration being called, if available 3629Sema::OwningExprResult 3630Sema::BuildResolvedCallExpr(Expr *Fn, NamedDecl *NDecl, 3631 SourceLocation LParenLoc, 3632 Expr **Args, unsigned NumArgs, 3633 SourceLocation RParenLoc) { 3634 FunctionDecl *FDecl = dyn_cast_or_null<FunctionDecl>(NDecl); 3635 3636 // Promote the function operand. 3637 UsualUnaryConversions(Fn); 3638 3639 // Make the call expr early, before semantic checks. This guarantees cleanup 3640 // of arguments and function on error. 3641 ExprOwningPtr<CallExpr> TheCall(this, new (Context) CallExpr(Context, Fn, 3642 Args, NumArgs, 3643 Context.BoolTy, 3644 RParenLoc)); 3645 3646 const FunctionType *FuncT; 3647 if (!Fn->getType()->isBlockPointerType()) { 3648 // C99 6.5.2.2p1 - "The expression that denotes the called function shall 3649 // have type pointer to function". 3650 const PointerType *PT = Fn->getType()->getAs<PointerType>(); 3651 if (PT == 0) 3652 return ExprError(Diag(LParenLoc, diag::err_typecheck_call_not_function) 3653 << Fn->getType() << Fn->getSourceRange()); 3654 FuncT = PT->getPointeeType()->getAs<FunctionType>(); 3655 } else { // This is a block call. 3656 FuncT = Fn->getType()->getAs<BlockPointerType>()->getPointeeType()-> 3657 getAs<FunctionType>(); 3658 } 3659 if (FuncT == 0) 3660 return ExprError(Diag(LParenLoc, diag::err_typecheck_call_not_function) 3661 << Fn->getType() << Fn->getSourceRange()); 3662 3663 // Check for a valid return type 3664 if (CheckCallReturnType(FuncT->getResultType(), 3665 Fn->getSourceRange().getBegin(), TheCall.get(), 3666 FDecl)) 3667 return ExprError(); 3668 3669 // We know the result type of the call, set it. 3670 TheCall->setType(FuncT->getResultType().getNonReferenceType()); 3671 3672 if (const FunctionProtoType *Proto = dyn_cast<FunctionProtoType>(FuncT)) { 3673 if (ConvertArgumentsForCall(&*TheCall, Fn, FDecl, Proto, Args, NumArgs, 3674 RParenLoc)) 3675 return ExprError(); 3676 } else { 3677 assert(isa<FunctionNoProtoType>(FuncT) && "Unknown FunctionType!"); 3678 3679 if (FDecl) { 3680 // Check if we have too few/too many template arguments, based 3681 // on our knowledge of the function definition. 3682 const FunctionDecl *Def = 0; 3683 if (FDecl->getBody(Def) && NumArgs != Def->param_size()) { 3684 const FunctionProtoType *Proto = 3685 Def->getType()->getAs<FunctionProtoType>(); 3686 if (!Proto || !(Proto->isVariadic() && NumArgs >= Def->param_size())) { 3687 Diag(RParenLoc, diag::warn_call_wrong_number_of_arguments) 3688 << (NumArgs > Def->param_size()) << FDecl << Fn->getSourceRange(); 3689 } 3690 } 3691 } 3692 3693 // Promote the arguments (C99 6.5.2.2p6). 3694 for (unsigned i = 0; i != NumArgs; i++) { 3695 Expr *Arg = Args[i]; 3696 DefaultArgumentPromotion(Arg); 3697 if (RequireCompleteType(Arg->getSourceRange().getBegin(), 3698 Arg->getType(), 3699 PDiag(diag::err_call_incomplete_argument) 3700 << Arg->getSourceRange())) 3701 return ExprError(); 3702 TheCall->setArg(i, Arg); 3703 } 3704 } 3705 3706 if (CXXMethodDecl *Method = dyn_cast_or_null<CXXMethodDecl>(FDecl)) 3707 if (!Method->isStatic()) 3708 return ExprError(Diag(LParenLoc, diag::err_member_call_without_object) 3709 << Fn->getSourceRange()); 3710 3711 // Check for sentinels 3712 if (NDecl) 3713 DiagnoseSentinelCalls(NDecl, LParenLoc, Args, NumArgs); 3714 3715 // Do special checking on direct calls to functions. 3716 if (FDecl) { 3717 if (CheckFunctionCall(FDecl, TheCall.get())) 3718 return ExprError(); 3719 3720 if (unsigned BuiltinID = FDecl->getBuiltinID()) 3721 return CheckBuiltinFunctionCall(BuiltinID, TheCall.take()); 3722 } else if (NDecl) { 3723 if (CheckBlockCall(NDecl, TheCall.get())) 3724 return ExprError(); 3725 } 3726 3727 return MaybeBindToTemporary(TheCall.take()); 3728} 3729 3730Action::OwningExprResult 3731Sema::ActOnCompoundLiteral(SourceLocation LParenLoc, TypeTy *Ty, 3732 SourceLocation RParenLoc, ExprArg InitExpr) { 3733 assert((Ty != 0) && "ActOnCompoundLiteral(): missing type"); 3734 // FIXME: put back this assert when initializers are worked out. 3735 //assert((InitExpr != 0) && "ActOnCompoundLiteral(): missing expression"); 3736 3737 TypeSourceInfo *TInfo; 3738 QualType literalType = GetTypeFromParser(Ty, &TInfo); 3739 if (!TInfo) 3740 TInfo = Context.getTrivialTypeSourceInfo(literalType); 3741 3742 return BuildCompoundLiteralExpr(LParenLoc, TInfo, RParenLoc, move(InitExpr)); 3743} 3744 3745Action::OwningExprResult 3746Sema::BuildCompoundLiteralExpr(SourceLocation LParenLoc, TypeSourceInfo *TInfo, 3747 SourceLocation RParenLoc, ExprArg InitExpr) { 3748 QualType literalType = TInfo->getType(); 3749 Expr *literalExpr = static_cast<Expr*>(InitExpr.get()); 3750 3751 if (literalType->isArrayType()) { 3752 if (literalType->isVariableArrayType()) 3753 return ExprError(Diag(LParenLoc, diag::err_variable_object_no_init) 3754 << SourceRange(LParenLoc, literalExpr->getSourceRange().getEnd())); 3755 } else if (!literalType->isDependentType() && 3756 RequireCompleteType(LParenLoc, literalType, 3757 PDiag(diag::err_typecheck_decl_incomplete_type) 3758 << SourceRange(LParenLoc, 3759 literalExpr->getSourceRange().getEnd()))) 3760 return ExprError(); 3761 3762 InitializedEntity Entity 3763 = InitializedEntity::InitializeTemporary(literalType); 3764 InitializationKind Kind 3765 = InitializationKind::CreateCast(SourceRange(LParenLoc, RParenLoc), 3766 /*IsCStyleCast=*/true); 3767 InitializationSequence InitSeq(*this, Entity, Kind, &literalExpr, 1); 3768 OwningExprResult Result = InitSeq.Perform(*this, Entity, Kind, 3769 MultiExprArg(*this, (void**)&literalExpr, 1), 3770 &literalType); 3771 if (Result.isInvalid()) 3772 return ExprError(); 3773 InitExpr.release(); 3774 literalExpr = static_cast<Expr*>(Result.get()); 3775 3776 bool isFileScope = getCurFunctionOrMethodDecl() == 0; 3777 if (isFileScope) { // 6.5.2.5p3 3778 if (CheckForConstantInitializer(literalExpr, literalType)) 3779 return ExprError(); 3780 } 3781 3782 Result.release(); 3783 3784 return Owned(new (Context) CompoundLiteralExpr(LParenLoc, TInfo, literalType, 3785 literalExpr, isFileScope)); 3786} 3787 3788Action::OwningExprResult 3789Sema::ActOnInitList(SourceLocation LBraceLoc, MultiExprArg initlist, 3790 SourceLocation RBraceLoc) { 3791 unsigned NumInit = initlist.size(); 3792 Expr **InitList = reinterpret_cast<Expr**>(initlist.release()); 3793 3794 // Semantic analysis for initializers is done by ActOnDeclarator() and 3795 // CheckInitializer() - it requires knowledge of the object being intialized. 3796 3797 InitListExpr *E = new (Context) InitListExpr(LBraceLoc, InitList, NumInit, 3798 RBraceLoc); 3799 E->setType(Context.VoidTy); // FIXME: just a place holder for now. 3800 return Owned(E); 3801} 3802 3803static CastExpr::CastKind getScalarCastKind(ASTContext &Context, 3804 QualType SrcTy, QualType DestTy) { 3805 if (Context.hasSameUnqualifiedType(SrcTy, DestTy)) 3806 return CastExpr::CK_NoOp; 3807 3808 if (SrcTy->hasPointerRepresentation()) { 3809 if (DestTy->hasPointerRepresentation()) 3810 return DestTy->isObjCObjectPointerType() ? 3811 CastExpr::CK_AnyPointerToObjCPointerCast : 3812 CastExpr::CK_BitCast; 3813 if (DestTy->isIntegerType()) 3814 return CastExpr::CK_PointerToIntegral; 3815 } 3816 3817 if (SrcTy->isIntegerType()) { 3818 if (DestTy->isIntegerType()) 3819 return CastExpr::CK_IntegralCast; 3820 if (DestTy->hasPointerRepresentation()) 3821 return CastExpr::CK_IntegralToPointer; 3822 if (DestTy->isRealFloatingType()) 3823 return CastExpr::CK_IntegralToFloating; 3824 } 3825 3826 if (SrcTy->isRealFloatingType()) { 3827 if (DestTy->isRealFloatingType()) 3828 return CastExpr::CK_FloatingCast; 3829 if (DestTy->isIntegerType()) 3830 return CastExpr::CK_FloatingToIntegral; 3831 } 3832 3833 // FIXME: Assert here. 3834 // assert(false && "Unhandled cast combination!"); 3835 return CastExpr::CK_Unknown; 3836} 3837 3838/// CheckCastTypes - Check type constraints for casting between types. 3839bool Sema::CheckCastTypes(SourceRange TyR, QualType castType, Expr *&castExpr, 3840 CastExpr::CastKind& Kind, 3841 CXXMethodDecl *& ConversionDecl, 3842 bool FunctionalStyle) { 3843 if (getLangOptions().CPlusPlus) 3844 return CXXCheckCStyleCast(TyR, castType, castExpr, Kind, FunctionalStyle, 3845 ConversionDecl); 3846 3847 DefaultFunctionArrayLvalueConversion(castExpr); 3848 3849 // C99 6.5.4p2: the cast type needs to be void or scalar and the expression 3850 // type needs to be scalar. 3851 if (castType->isVoidType()) { 3852 // Cast to void allows any expr type. 3853 Kind = CastExpr::CK_ToVoid; 3854 return false; 3855 } 3856 3857 if (!castType->isScalarType() && !castType->isVectorType()) { 3858 if (Context.hasSameUnqualifiedType(castType, castExpr->getType()) && 3859 (castType->isStructureType() || castType->isUnionType())) { 3860 // GCC struct/union extension: allow cast to self. 3861 // FIXME: Check that the cast destination type is complete. 3862 Diag(TyR.getBegin(), diag::ext_typecheck_cast_nonscalar) 3863 << castType << castExpr->getSourceRange(); 3864 Kind = CastExpr::CK_NoOp; 3865 return false; 3866 } 3867 3868 if (castType->isUnionType()) { 3869 // GCC cast to union extension 3870 RecordDecl *RD = castType->getAs<RecordType>()->getDecl(); 3871 RecordDecl::field_iterator Field, FieldEnd; 3872 for (Field = RD->field_begin(), FieldEnd = RD->field_end(); 3873 Field != FieldEnd; ++Field) { 3874 if (Context.hasSameUnqualifiedType(Field->getType(), 3875 castExpr->getType())) { 3876 Diag(TyR.getBegin(), diag::ext_typecheck_cast_to_union) 3877 << castExpr->getSourceRange(); 3878 break; 3879 } 3880 } 3881 if (Field == FieldEnd) 3882 return Diag(TyR.getBegin(), diag::err_typecheck_cast_to_union_no_type) 3883 << castExpr->getType() << castExpr->getSourceRange(); 3884 Kind = CastExpr::CK_ToUnion; 3885 return false; 3886 } 3887 3888 // Reject any other conversions to non-scalar types. 3889 return Diag(TyR.getBegin(), diag::err_typecheck_cond_expect_scalar) 3890 << castType << castExpr->getSourceRange(); 3891 } 3892 3893 if (!castExpr->getType()->isScalarType() && 3894 !castExpr->getType()->isVectorType()) { 3895 return Diag(castExpr->getLocStart(), 3896 diag::err_typecheck_expect_scalar_operand) 3897 << castExpr->getType() << castExpr->getSourceRange(); 3898 } 3899 3900 if (castType->isExtVectorType()) 3901 return CheckExtVectorCast(TyR, castType, castExpr, Kind); 3902 3903 if (castType->isVectorType()) 3904 return CheckVectorCast(TyR, castType, castExpr->getType(), Kind); 3905 if (castExpr->getType()->isVectorType()) 3906 return CheckVectorCast(TyR, castExpr->getType(), castType, Kind); 3907 3908 if (getLangOptions().ObjC1 && isa<ObjCSuperExpr>(castExpr)) 3909 return Diag(castExpr->getLocStart(), diag::err_illegal_super_cast) << TyR; 3910 3911 if (isa<ObjCSelectorExpr>(castExpr)) 3912 return Diag(castExpr->getLocStart(), diag::err_cast_selector_expr); 3913 3914 if (!castType->isArithmeticType()) { 3915 QualType castExprType = castExpr->getType(); 3916 if (!castExprType->isIntegralType() && castExprType->isArithmeticType()) 3917 return Diag(castExpr->getLocStart(), 3918 diag::err_cast_pointer_from_non_pointer_int) 3919 << castExprType << castExpr->getSourceRange(); 3920 } else if (!castExpr->getType()->isArithmeticType()) { 3921 if (!castType->isIntegralType() && castType->isArithmeticType()) 3922 return Diag(castExpr->getLocStart(), 3923 diag::err_cast_pointer_to_non_pointer_int) 3924 << castType << castExpr->getSourceRange(); 3925 } 3926 3927 Kind = getScalarCastKind(Context, castExpr->getType(), castType); 3928 return false; 3929} 3930 3931bool Sema::CheckVectorCast(SourceRange R, QualType VectorTy, QualType Ty, 3932 CastExpr::CastKind &Kind) { 3933 assert(VectorTy->isVectorType() && "Not a vector type!"); 3934 3935 if (Ty->isVectorType() || Ty->isIntegerType()) { 3936 if (Context.getTypeSize(VectorTy) != Context.getTypeSize(Ty)) 3937 return Diag(R.getBegin(), 3938 Ty->isVectorType() ? 3939 diag::err_invalid_conversion_between_vectors : 3940 diag::err_invalid_conversion_between_vector_and_integer) 3941 << VectorTy << Ty << R; 3942 } else 3943 return Diag(R.getBegin(), 3944 diag::err_invalid_conversion_between_vector_and_scalar) 3945 << VectorTy << Ty << R; 3946 3947 Kind = CastExpr::CK_BitCast; 3948 return false; 3949} 3950 3951bool Sema::CheckExtVectorCast(SourceRange R, QualType DestTy, Expr *&CastExpr, 3952 CastExpr::CastKind &Kind) { 3953 assert(DestTy->isExtVectorType() && "Not an extended vector type!"); 3954 3955 QualType SrcTy = CastExpr->getType(); 3956 3957 // If SrcTy is a VectorType, the total size must match to explicitly cast to 3958 // an ExtVectorType. 3959 if (SrcTy->isVectorType()) { 3960 if (Context.getTypeSize(DestTy) != Context.getTypeSize(SrcTy)) 3961 return Diag(R.getBegin(),diag::err_invalid_conversion_between_ext_vectors) 3962 << DestTy << SrcTy << R; 3963 Kind = CastExpr::CK_BitCast; 3964 return false; 3965 } 3966 3967 // All non-pointer scalars can be cast to ExtVector type. The appropriate 3968 // conversion will take place first from scalar to elt type, and then 3969 // splat from elt type to vector. 3970 if (SrcTy->isPointerType()) 3971 return Diag(R.getBegin(), 3972 diag::err_invalid_conversion_between_vector_and_scalar) 3973 << DestTy << SrcTy << R; 3974 3975 QualType DestElemTy = DestTy->getAs<ExtVectorType>()->getElementType(); 3976 ImpCastExprToType(CastExpr, DestElemTy, 3977 getScalarCastKind(Context, SrcTy, DestElemTy)); 3978 3979 Kind = CastExpr::CK_VectorSplat; 3980 return false; 3981} 3982 3983Action::OwningExprResult 3984Sema::ActOnCastExpr(Scope *S, SourceLocation LParenLoc, TypeTy *Ty, 3985 SourceLocation RParenLoc, ExprArg Op) { 3986 assert((Ty != 0) && (Op.get() != 0) && 3987 "ActOnCastExpr(): missing type or expr"); 3988 3989 TypeSourceInfo *castTInfo; 3990 QualType castType = GetTypeFromParser(Ty, &castTInfo); 3991 if (!castTInfo) 3992 castTInfo = Context.getTrivialTypeSourceInfo(castType); 3993 3994 // If the Expr being casted is a ParenListExpr, handle it specially. 3995 Expr *castExpr = (Expr *)Op.get(); 3996 if (isa<ParenListExpr>(castExpr)) 3997 return ActOnCastOfParenListExpr(S, LParenLoc, RParenLoc, move(Op), 3998 castTInfo); 3999 4000 return BuildCStyleCastExpr(LParenLoc, castTInfo, RParenLoc, move(Op)); 4001} 4002 4003Action::OwningExprResult 4004Sema::BuildCStyleCastExpr(SourceLocation LParenLoc, TypeSourceInfo *Ty, 4005 SourceLocation RParenLoc, ExprArg Op) { 4006 Expr *castExpr = static_cast<Expr*>(Op.get()); 4007 4008 CXXMethodDecl *Method = 0; 4009 CastExpr::CastKind Kind = CastExpr::CK_Unknown; 4010 if (CheckCastTypes(SourceRange(LParenLoc, RParenLoc), Ty->getType(), castExpr, 4011 Kind, Method)) 4012 return ExprError(); 4013 4014 if (Method) { 4015 // FIXME: preserve type source info here 4016 OwningExprResult CastArg = BuildCXXCastArgument(LParenLoc, Ty->getType(), 4017 Kind, Method, move(Op)); 4018 4019 if (CastArg.isInvalid()) 4020 return ExprError(); 4021 4022 castExpr = CastArg.takeAs<Expr>(); 4023 } else { 4024 Op.release(); 4025 } 4026 4027 return Owned(new (Context) CStyleCastExpr(Ty->getType().getNonReferenceType(), 4028 Kind, castExpr, Ty, 4029 LParenLoc, RParenLoc)); 4030} 4031 4032/// This is not an AltiVec-style cast, so turn the ParenListExpr into a sequence 4033/// of comma binary operators. 4034Action::OwningExprResult 4035Sema::MaybeConvertParenListExprToParenExpr(Scope *S, ExprArg EA) { 4036 Expr *expr = EA.takeAs<Expr>(); 4037 ParenListExpr *E = dyn_cast<ParenListExpr>(expr); 4038 if (!E) 4039 return Owned(expr); 4040 4041 OwningExprResult Result(*this, E->getExpr(0)); 4042 4043 for (unsigned i = 1, e = E->getNumExprs(); i != e && !Result.isInvalid(); ++i) 4044 Result = ActOnBinOp(S, E->getExprLoc(), tok::comma, move(Result), 4045 Owned(E->getExpr(i))); 4046 4047 return ActOnParenExpr(E->getLParenLoc(), E->getRParenLoc(), move(Result)); 4048} 4049 4050Action::OwningExprResult 4051Sema::ActOnCastOfParenListExpr(Scope *S, SourceLocation LParenLoc, 4052 SourceLocation RParenLoc, ExprArg Op, 4053 TypeSourceInfo *TInfo) { 4054 ParenListExpr *PE = (ParenListExpr *)Op.get(); 4055 QualType Ty = TInfo->getType(); 4056 4057 // If this is an altivec initializer, '(' type ')' '(' init, ..., init ')' 4058 // then handle it as such. 4059 if (getLangOptions().AltiVec && Ty->isVectorType()) { 4060 if (PE->getNumExprs() == 0) { 4061 Diag(PE->getExprLoc(), diag::err_altivec_empty_initializer); 4062 return ExprError(); 4063 } 4064 4065 llvm::SmallVector<Expr *, 8> initExprs; 4066 for (unsigned i = 0, e = PE->getNumExprs(); i != e; ++i) 4067 initExprs.push_back(PE->getExpr(i)); 4068 4069 // FIXME: This means that pretty-printing the final AST will produce curly 4070 // braces instead of the original commas. 4071 Op.release(); 4072 InitListExpr *E = new (Context) InitListExpr(LParenLoc, &initExprs[0], 4073 initExprs.size(), RParenLoc); 4074 E->setType(Ty); 4075 return BuildCompoundLiteralExpr(LParenLoc, TInfo, RParenLoc, Owned(E)); 4076 } else { 4077 // This is not an AltiVec-style cast, so turn the ParenListExpr into a 4078 // sequence of BinOp comma operators. 4079 Op = MaybeConvertParenListExprToParenExpr(S, move(Op)); 4080 return BuildCStyleCastExpr(LParenLoc, TInfo, RParenLoc, move(Op)); 4081 } 4082} 4083 4084Action::OwningExprResult Sema::ActOnParenOrParenListExpr(SourceLocation L, 4085 SourceLocation R, 4086 MultiExprArg Val, 4087 TypeTy *TypeOfCast) { 4088 unsigned nexprs = Val.size(); 4089 Expr **exprs = reinterpret_cast<Expr**>(Val.release()); 4090 assert((exprs != 0) && "ActOnParenOrParenListExpr() missing expr list"); 4091 Expr *expr; 4092 if (nexprs == 1 && TypeOfCast && !TypeIsVectorType(TypeOfCast)) 4093 expr = new (Context) ParenExpr(L, R, exprs[0]); 4094 else 4095 expr = new (Context) ParenListExpr(Context, L, exprs, nexprs, R); 4096 return Owned(expr); 4097} 4098 4099/// Note that lhs is not null here, even if this is the gnu "x ?: y" extension. 4100/// In that case, lhs = cond. 4101/// C99 6.5.15 4102QualType Sema::CheckConditionalOperands(Expr *&Cond, Expr *&LHS, Expr *&RHS, 4103 SourceLocation QuestionLoc) { 4104 // C++ is sufficiently different to merit its own checker. 4105 if (getLangOptions().CPlusPlus) 4106 return CXXCheckConditionalOperands(Cond, LHS, RHS, QuestionLoc); 4107 4108 CheckSignCompare(LHS, RHS, QuestionLoc); 4109 4110 UsualUnaryConversions(Cond); 4111 UsualUnaryConversions(LHS); 4112 UsualUnaryConversions(RHS); 4113 QualType CondTy = Cond->getType(); 4114 QualType LHSTy = LHS->getType(); 4115 QualType RHSTy = RHS->getType(); 4116 4117 // first, check the condition. 4118 if (!CondTy->isScalarType()) { // C99 6.5.15p2 4119 Diag(Cond->getLocStart(), diag::err_typecheck_cond_expect_scalar) 4120 << CondTy; 4121 return QualType(); 4122 } 4123 4124 // Now check the two expressions. 4125 if (LHSTy->isVectorType() || RHSTy->isVectorType()) 4126 return CheckVectorOperands(QuestionLoc, LHS, RHS); 4127 4128 // If both operands have arithmetic type, do the usual arithmetic conversions 4129 // to find a common type: C99 6.5.15p3,5. 4130 if (LHSTy->isArithmeticType() && RHSTy->isArithmeticType()) { 4131 UsualArithmeticConversions(LHS, RHS); 4132 return LHS->getType(); 4133 } 4134 4135 // If both operands are the same structure or union type, the result is that 4136 // type. 4137 if (const RecordType *LHSRT = LHSTy->getAs<RecordType>()) { // C99 6.5.15p3 4138 if (const RecordType *RHSRT = RHSTy->getAs<RecordType>()) 4139 if (LHSRT->getDecl() == RHSRT->getDecl()) 4140 // "If both the operands have structure or union type, the result has 4141 // that type." This implies that CV qualifiers are dropped. 4142 return LHSTy.getUnqualifiedType(); 4143 // FIXME: Type of conditional expression must be complete in C mode. 4144 } 4145 4146 // C99 6.5.15p5: "If both operands have void type, the result has void type." 4147 // The following || allows only one side to be void (a GCC-ism). 4148 if (LHSTy->isVoidType() || RHSTy->isVoidType()) { 4149 if (!LHSTy->isVoidType()) 4150 Diag(RHS->getLocStart(), diag::ext_typecheck_cond_one_void) 4151 << RHS->getSourceRange(); 4152 if (!RHSTy->isVoidType()) 4153 Diag(LHS->getLocStart(), diag::ext_typecheck_cond_one_void) 4154 << LHS->getSourceRange(); 4155 ImpCastExprToType(LHS, Context.VoidTy, CastExpr::CK_ToVoid); 4156 ImpCastExprToType(RHS, Context.VoidTy, CastExpr::CK_ToVoid); 4157 return Context.VoidTy; 4158 } 4159 // C99 6.5.15p6 - "if one operand is a null pointer constant, the result has 4160 // the type of the other operand." 4161 if ((LHSTy->isAnyPointerType() || LHSTy->isBlockPointerType()) && 4162 RHS->isNullPointerConstant(Context, Expr::NPC_ValueDependentIsNull)) { 4163 // promote the null to a pointer. 4164 ImpCastExprToType(RHS, LHSTy, CastExpr::CK_Unknown); 4165 return LHSTy; 4166 } 4167 if ((RHSTy->isAnyPointerType() || RHSTy->isBlockPointerType()) && 4168 LHS->isNullPointerConstant(Context, Expr::NPC_ValueDependentIsNull)) { 4169 ImpCastExprToType(LHS, RHSTy, CastExpr::CK_Unknown); 4170 return RHSTy; 4171 } 4172 4173 // All objective-c pointer type analysis is done here. 4174 QualType compositeType = FindCompositeObjCPointerType(LHS, RHS, 4175 QuestionLoc); 4176 if (!compositeType.isNull()) 4177 return compositeType; 4178 4179 4180 // Handle block pointer types. 4181 if (LHSTy->isBlockPointerType() || RHSTy->isBlockPointerType()) { 4182 if (!LHSTy->isBlockPointerType() || !RHSTy->isBlockPointerType()) { 4183 if (LHSTy->isVoidPointerType() || RHSTy->isVoidPointerType()) { 4184 QualType destType = Context.getPointerType(Context.VoidTy); 4185 ImpCastExprToType(LHS, destType, CastExpr::CK_BitCast); 4186 ImpCastExprToType(RHS, destType, CastExpr::CK_BitCast); 4187 return destType; 4188 } 4189 Diag(QuestionLoc, diag::err_typecheck_cond_incompatible_operands) 4190 << LHSTy << RHSTy << LHS->getSourceRange() << RHS->getSourceRange(); 4191 return QualType(); 4192 } 4193 // We have 2 block pointer types. 4194 if (Context.getCanonicalType(LHSTy) == Context.getCanonicalType(RHSTy)) { 4195 // Two identical block pointer types are always compatible. 4196 return LHSTy; 4197 } 4198 // The block pointer types aren't identical, continue checking. 4199 QualType lhptee = LHSTy->getAs<BlockPointerType>()->getPointeeType(); 4200 QualType rhptee = RHSTy->getAs<BlockPointerType>()->getPointeeType(); 4201 4202 if (!Context.typesAreCompatible(lhptee.getUnqualifiedType(), 4203 rhptee.getUnqualifiedType())) { 4204 Diag(QuestionLoc, diag::warn_typecheck_cond_incompatible_pointers) 4205 << LHSTy << RHSTy << LHS->getSourceRange() << RHS->getSourceRange(); 4206 // In this situation, we assume void* type. No especially good 4207 // reason, but this is what gcc does, and we do have to pick 4208 // to get a consistent AST. 4209 QualType incompatTy = Context.getPointerType(Context.VoidTy); 4210 ImpCastExprToType(LHS, incompatTy, CastExpr::CK_BitCast); 4211 ImpCastExprToType(RHS, incompatTy, CastExpr::CK_BitCast); 4212 return incompatTy; 4213 } 4214 // The block pointer types are compatible. 4215 ImpCastExprToType(LHS, LHSTy, CastExpr::CK_BitCast); 4216 ImpCastExprToType(RHS, LHSTy, CastExpr::CK_BitCast); 4217 return LHSTy; 4218 } 4219 4220 // Check constraints for C object pointers types (C99 6.5.15p3,6). 4221 if (LHSTy->isPointerType() && RHSTy->isPointerType()) { 4222 // get the "pointed to" types 4223 QualType lhptee = LHSTy->getAs<PointerType>()->getPointeeType(); 4224 QualType rhptee = RHSTy->getAs<PointerType>()->getPointeeType(); 4225 4226 // ignore qualifiers on void (C99 6.5.15p3, clause 6) 4227 if (lhptee->isVoidType() && rhptee->isIncompleteOrObjectType()) { 4228 // Figure out necessary qualifiers (C99 6.5.15p6) 4229 QualType destPointee 4230 = Context.getQualifiedType(lhptee, rhptee.getQualifiers()); 4231 QualType destType = Context.getPointerType(destPointee); 4232 // Add qualifiers if necessary. 4233 ImpCastExprToType(LHS, destType, CastExpr::CK_NoOp); 4234 // Promote to void*. 4235 ImpCastExprToType(RHS, destType, CastExpr::CK_BitCast); 4236 return destType; 4237 } 4238 if (rhptee->isVoidType() && lhptee->isIncompleteOrObjectType()) { 4239 QualType destPointee 4240 = Context.getQualifiedType(rhptee, lhptee.getQualifiers()); 4241 QualType destType = Context.getPointerType(destPointee); 4242 // Add qualifiers if necessary. 4243 ImpCastExprToType(RHS, destType, CastExpr::CK_NoOp); 4244 // Promote to void*. 4245 ImpCastExprToType(LHS, destType, CastExpr::CK_BitCast); 4246 return destType; 4247 } 4248 4249 if (Context.getCanonicalType(LHSTy) == Context.getCanonicalType(RHSTy)) { 4250 // Two identical pointer types are always compatible. 4251 return LHSTy; 4252 } 4253 if (!Context.typesAreCompatible(lhptee.getUnqualifiedType(), 4254 rhptee.getUnqualifiedType())) { 4255 Diag(QuestionLoc, diag::warn_typecheck_cond_incompatible_pointers) 4256 << LHSTy << RHSTy << LHS->getSourceRange() << RHS->getSourceRange(); 4257 // In this situation, we assume void* type. No especially good 4258 // reason, but this is what gcc does, and we do have to pick 4259 // to get a consistent AST. 4260 QualType incompatTy = Context.getPointerType(Context.VoidTy); 4261 ImpCastExprToType(LHS, incompatTy, CastExpr::CK_BitCast); 4262 ImpCastExprToType(RHS, incompatTy, CastExpr::CK_BitCast); 4263 return incompatTy; 4264 } 4265 // The pointer types are compatible. 4266 // C99 6.5.15p6: If both operands are pointers to compatible types *or* to 4267 // differently qualified versions of compatible types, the result type is 4268 // a pointer to an appropriately qualified version of the *composite* 4269 // type. 4270 // FIXME: Need to calculate the composite type. 4271 // FIXME: Need to add qualifiers 4272 ImpCastExprToType(LHS, LHSTy, CastExpr::CK_BitCast); 4273 ImpCastExprToType(RHS, LHSTy, CastExpr::CK_BitCast); 4274 return LHSTy; 4275 } 4276 4277 // GCC compatibility: soften pointer/integer mismatch. 4278 if (RHSTy->isPointerType() && LHSTy->isIntegerType()) { 4279 Diag(QuestionLoc, diag::warn_typecheck_cond_pointer_integer_mismatch) 4280 << LHSTy << RHSTy << LHS->getSourceRange() << RHS->getSourceRange(); 4281 ImpCastExprToType(LHS, RHSTy, CastExpr::CK_IntegralToPointer); 4282 return RHSTy; 4283 } 4284 if (LHSTy->isPointerType() && RHSTy->isIntegerType()) { 4285 Diag(QuestionLoc, diag::warn_typecheck_cond_pointer_integer_mismatch) 4286 << LHSTy << RHSTy << LHS->getSourceRange() << RHS->getSourceRange(); 4287 ImpCastExprToType(RHS, LHSTy, CastExpr::CK_IntegralToPointer); 4288 return LHSTy; 4289 } 4290 4291 // Otherwise, the operands are not compatible. 4292 Diag(QuestionLoc, diag::err_typecheck_cond_incompatible_operands) 4293 << LHSTy << RHSTy << LHS->getSourceRange() << RHS->getSourceRange(); 4294 return QualType(); 4295} 4296 4297/// FindCompositeObjCPointerType - Helper method to find composite type of 4298/// two objective-c pointer types of the two input expressions. 4299QualType Sema::FindCompositeObjCPointerType(Expr *&LHS, Expr *&RHS, 4300 SourceLocation QuestionLoc) { 4301 QualType LHSTy = LHS->getType(); 4302 QualType RHSTy = RHS->getType(); 4303 4304 // Handle things like Class and struct objc_class*. Here we case the result 4305 // to the pseudo-builtin, because that will be implicitly cast back to the 4306 // redefinition type if an attempt is made to access its fields. 4307 if (LHSTy->isObjCClassType() && 4308 (RHSTy.getDesugaredType() == Context.ObjCClassRedefinitionType)) { 4309 ImpCastExprToType(RHS, LHSTy, CastExpr::CK_BitCast); 4310 return LHSTy; 4311 } 4312 if (RHSTy->isObjCClassType() && 4313 (LHSTy.getDesugaredType() == Context.ObjCClassRedefinitionType)) { 4314 ImpCastExprToType(LHS, RHSTy, CastExpr::CK_BitCast); 4315 return RHSTy; 4316 } 4317 // And the same for struct objc_object* / id 4318 if (LHSTy->isObjCIdType() && 4319 (RHSTy.getDesugaredType() == Context.ObjCIdRedefinitionType)) { 4320 ImpCastExprToType(RHS, LHSTy, CastExpr::CK_BitCast); 4321 return LHSTy; 4322 } 4323 if (RHSTy->isObjCIdType() && 4324 (LHSTy.getDesugaredType() == Context.ObjCIdRedefinitionType)) { 4325 ImpCastExprToType(LHS, RHSTy, CastExpr::CK_BitCast); 4326 return RHSTy; 4327 } 4328 // And the same for struct objc_selector* / SEL 4329 if (Context.isObjCSelType(LHSTy) && 4330 (RHSTy.getDesugaredType() == Context.ObjCSelRedefinitionType)) { 4331 ImpCastExprToType(RHS, LHSTy, CastExpr::CK_BitCast); 4332 return LHSTy; 4333 } 4334 if (Context.isObjCSelType(RHSTy) && 4335 (LHSTy.getDesugaredType() == Context.ObjCSelRedefinitionType)) { 4336 ImpCastExprToType(LHS, RHSTy, CastExpr::CK_BitCast); 4337 return RHSTy; 4338 } 4339 // Check constraints for Objective-C object pointers types. 4340 if (LHSTy->isObjCObjectPointerType() && RHSTy->isObjCObjectPointerType()) { 4341 4342 if (Context.getCanonicalType(LHSTy) == Context.getCanonicalType(RHSTy)) { 4343 // Two identical object pointer types are always compatible. 4344 return LHSTy; 4345 } 4346 const ObjCObjectPointerType *LHSOPT = LHSTy->getAs<ObjCObjectPointerType>(); 4347 const ObjCObjectPointerType *RHSOPT = RHSTy->getAs<ObjCObjectPointerType>(); 4348 QualType compositeType = LHSTy; 4349 4350 // If both operands are interfaces and either operand can be 4351 // assigned to the other, use that type as the composite 4352 // type. This allows 4353 // xxx ? (A*) a : (B*) b 4354 // where B is a subclass of A. 4355 // 4356 // Additionally, as for assignment, if either type is 'id' 4357 // allow silent coercion. Finally, if the types are 4358 // incompatible then make sure to use 'id' as the composite 4359 // type so the result is acceptable for sending messages to. 4360 4361 // FIXME: Consider unifying with 'areComparableObjCPointerTypes'. 4362 // It could return the composite type. 4363 if (Context.canAssignObjCInterfaces(LHSOPT, RHSOPT)) { 4364 compositeType = RHSOPT->isObjCBuiltinType() ? RHSTy : LHSTy; 4365 } else if (Context.canAssignObjCInterfaces(RHSOPT, LHSOPT)) { 4366 compositeType = LHSOPT->isObjCBuiltinType() ? LHSTy : RHSTy; 4367 } else if ((LHSTy->isObjCQualifiedIdType() || 4368 RHSTy->isObjCQualifiedIdType()) && 4369 Context.ObjCQualifiedIdTypesAreCompatible(LHSTy, RHSTy, true)) { 4370 // Need to handle "id<xx>" explicitly. 4371 // GCC allows qualified id and any Objective-C type to devolve to 4372 // id. Currently localizing to here until clear this should be 4373 // part of ObjCQualifiedIdTypesAreCompatible. 4374 compositeType = Context.getObjCIdType(); 4375 } else if (LHSTy->isObjCIdType() || RHSTy->isObjCIdType()) { 4376 compositeType = Context.getObjCIdType(); 4377 } else if (!(compositeType = 4378 Context.areCommonBaseCompatible(LHSOPT, RHSOPT)).isNull()) 4379 ; 4380 else { 4381 Diag(QuestionLoc, diag::ext_typecheck_cond_incompatible_operands) 4382 << LHSTy << RHSTy 4383 << LHS->getSourceRange() << RHS->getSourceRange(); 4384 QualType incompatTy = Context.getObjCIdType(); 4385 ImpCastExprToType(LHS, incompatTy, CastExpr::CK_BitCast); 4386 ImpCastExprToType(RHS, incompatTy, CastExpr::CK_BitCast); 4387 return incompatTy; 4388 } 4389 // The object pointer types are compatible. 4390 ImpCastExprToType(LHS, compositeType, CastExpr::CK_BitCast); 4391 ImpCastExprToType(RHS, compositeType, CastExpr::CK_BitCast); 4392 return compositeType; 4393 } 4394 // Check Objective-C object pointer types and 'void *' 4395 if (LHSTy->isVoidPointerType() && RHSTy->isObjCObjectPointerType()) { 4396 QualType lhptee = LHSTy->getAs<PointerType>()->getPointeeType(); 4397 QualType rhptee = RHSTy->getAs<ObjCObjectPointerType>()->getPointeeType(); 4398 QualType destPointee 4399 = Context.getQualifiedType(lhptee, rhptee.getQualifiers()); 4400 QualType destType = Context.getPointerType(destPointee); 4401 // Add qualifiers if necessary. 4402 ImpCastExprToType(LHS, destType, CastExpr::CK_NoOp); 4403 // Promote to void*. 4404 ImpCastExprToType(RHS, destType, CastExpr::CK_BitCast); 4405 return destType; 4406 } 4407 if (LHSTy->isObjCObjectPointerType() && RHSTy->isVoidPointerType()) { 4408 QualType lhptee = LHSTy->getAs<ObjCObjectPointerType>()->getPointeeType(); 4409 QualType rhptee = RHSTy->getAs<PointerType>()->getPointeeType(); 4410 QualType destPointee 4411 = Context.getQualifiedType(rhptee, lhptee.getQualifiers()); 4412 QualType destType = Context.getPointerType(destPointee); 4413 // Add qualifiers if necessary. 4414 ImpCastExprToType(RHS, destType, CastExpr::CK_NoOp); 4415 // Promote to void*. 4416 ImpCastExprToType(LHS, destType, CastExpr::CK_BitCast); 4417 return destType; 4418 } 4419 return QualType(); 4420} 4421 4422/// ActOnConditionalOp - Parse a ?: operation. Note that 'LHS' may be null 4423/// in the case of a the GNU conditional expr extension. 4424Action::OwningExprResult Sema::ActOnConditionalOp(SourceLocation QuestionLoc, 4425 SourceLocation ColonLoc, 4426 ExprArg Cond, ExprArg LHS, 4427 ExprArg RHS) { 4428 Expr *CondExpr = (Expr *) Cond.get(); 4429 Expr *LHSExpr = (Expr *) LHS.get(), *RHSExpr = (Expr *) RHS.get(); 4430 4431 // If this is the gnu "x ?: y" extension, analyze the types as though the LHS 4432 // was the condition. 4433 bool isLHSNull = LHSExpr == 0; 4434 if (isLHSNull) 4435 LHSExpr = CondExpr; 4436 4437 QualType result = CheckConditionalOperands(CondExpr, LHSExpr, 4438 RHSExpr, QuestionLoc); 4439 if (result.isNull()) 4440 return ExprError(); 4441 4442 Cond.release(); 4443 LHS.release(); 4444 RHS.release(); 4445 return Owned(new (Context) ConditionalOperator(CondExpr, QuestionLoc, 4446 isLHSNull ? 0 : LHSExpr, 4447 ColonLoc, RHSExpr, result)); 4448} 4449 4450// CheckPointerTypesForAssignment - This is a very tricky routine (despite 4451// being closely modeled after the C99 spec:-). The odd characteristic of this 4452// routine is it effectively iqnores the qualifiers on the top level pointee. 4453// This circumvents the usual type rules specified in 6.2.7p1 & 6.7.5.[1-3]. 4454// FIXME: add a couple examples in this comment. 4455Sema::AssignConvertType 4456Sema::CheckPointerTypesForAssignment(QualType lhsType, QualType rhsType) { 4457 QualType lhptee, rhptee; 4458 4459 if ((lhsType->isObjCClassType() && 4460 (rhsType.getDesugaredType() == Context.ObjCClassRedefinitionType)) || 4461 (rhsType->isObjCClassType() && 4462 (lhsType.getDesugaredType() == Context.ObjCClassRedefinitionType))) { 4463 return Compatible; 4464 } 4465 4466 // get the "pointed to" type (ignoring qualifiers at the top level) 4467 lhptee = lhsType->getAs<PointerType>()->getPointeeType(); 4468 rhptee = rhsType->getAs<PointerType>()->getPointeeType(); 4469 4470 // make sure we operate on the canonical type 4471 lhptee = Context.getCanonicalType(lhptee); 4472 rhptee = Context.getCanonicalType(rhptee); 4473 4474 AssignConvertType ConvTy = Compatible; 4475 4476 // C99 6.5.16.1p1: This following citation is common to constraints 4477 // 3 & 4 (below). ...and the type *pointed to* by the left has all the 4478 // qualifiers of the type *pointed to* by the right; 4479 // FIXME: Handle ExtQualType 4480 if (!lhptee.isAtLeastAsQualifiedAs(rhptee)) 4481 ConvTy = CompatiblePointerDiscardsQualifiers; 4482 4483 // C99 6.5.16.1p1 (constraint 4): If one operand is a pointer to an object or 4484 // incomplete type and the other is a pointer to a qualified or unqualified 4485 // version of void... 4486 if (lhptee->isVoidType()) { 4487 if (rhptee->isIncompleteOrObjectType()) 4488 return ConvTy; 4489 4490 // As an extension, we allow cast to/from void* to function pointer. 4491 assert(rhptee->isFunctionType()); 4492 return FunctionVoidPointer; 4493 } 4494 4495 if (rhptee->isVoidType()) { 4496 if (lhptee->isIncompleteOrObjectType()) 4497 return ConvTy; 4498 4499 // As an extension, we allow cast to/from void* to function pointer. 4500 assert(lhptee->isFunctionType()); 4501 return FunctionVoidPointer; 4502 } 4503 // C99 6.5.16.1p1 (constraint 3): both operands are pointers to qualified or 4504 // unqualified versions of compatible types, ... 4505 lhptee = lhptee.getUnqualifiedType(); 4506 rhptee = rhptee.getUnqualifiedType(); 4507 if (!Context.typesAreCompatible(lhptee, rhptee)) { 4508 // Check if the pointee types are compatible ignoring the sign. 4509 // We explicitly check for char so that we catch "char" vs 4510 // "unsigned char" on systems where "char" is unsigned. 4511 if (lhptee->isCharType()) 4512 lhptee = Context.UnsignedCharTy; 4513 else if (lhptee->isSignedIntegerType()) 4514 lhptee = Context.getCorrespondingUnsignedType(lhptee); 4515 4516 if (rhptee->isCharType()) 4517 rhptee = Context.UnsignedCharTy; 4518 else if (rhptee->isSignedIntegerType()) 4519 rhptee = Context.getCorrespondingUnsignedType(rhptee); 4520 4521 if (lhptee == rhptee) { 4522 // Types are compatible ignoring the sign. Qualifier incompatibility 4523 // takes priority over sign incompatibility because the sign 4524 // warning can be disabled. 4525 if (ConvTy != Compatible) 4526 return ConvTy; 4527 return IncompatiblePointerSign; 4528 } 4529 4530 // If we are a multi-level pointer, it's possible that our issue is simply 4531 // one of qualification - e.g. char ** -> const char ** is not allowed. If 4532 // the eventual target type is the same and the pointers have the same 4533 // level of indirection, this must be the issue. 4534 if (lhptee->isPointerType() && rhptee->isPointerType()) { 4535 do { 4536 lhptee = lhptee->getAs<PointerType>()->getPointeeType(); 4537 rhptee = rhptee->getAs<PointerType>()->getPointeeType(); 4538 4539 lhptee = Context.getCanonicalType(lhptee); 4540 rhptee = Context.getCanonicalType(rhptee); 4541 } while (lhptee->isPointerType() && rhptee->isPointerType()); 4542 4543 if (Context.hasSameUnqualifiedType(lhptee, rhptee)) 4544 return IncompatibleNestedPointerQualifiers; 4545 } 4546 4547 // General pointer incompatibility takes priority over qualifiers. 4548 return IncompatiblePointer; 4549 } 4550 return ConvTy; 4551} 4552 4553/// CheckBlockPointerTypesForAssignment - This routine determines whether two 4554/// block pointer types are compatible or whether a block and normal pointer 4555/// are compatible. It is more restrict than comparing two function pointer 4556// types. 4557Sema::AssignConvertType 4558Sema::CheckBlockPointerTypesForAssignment(QualType lhsType, 4559 QualType rhsType) { 4560 QualType lhptee, rhptee; 4561 4562 // get the "pointed to" type (ignoring qualifiers at the top level) 4563 lhptee = lhsType->getAs<BlockPointerType>()->getPointeeType(); 4564 rhptee = rhsType->getAs<BlockPointerType>()->getPointeeType(); 4565 4566 // make sure we operate on the canonical type 4567 lhptee = Context.getCanonicalType(lhptee); 4568 rhptee = Context.getCanonicalType(rhptee); 4569 4570 AssignConvertType ConvTy = Compatible; 4571 4572 // For blocks we enforce that qualifiers are identical. 4573 if (lhptee.getLocalCVRQualifiers() != rhptee.getLocalCVRQualifiers()) 4574 ConvTy = CompatiblePointerDiscardsQualifiers; 4575 4576 if (!Context.typesAreCompatible(lhptee, rhptee)) 4577 return IncompatibleBlockPointer; 4578 return ConvTy; 4579} 4580 4581/// CheckObjCPointerTypesForAssignment - Compares two objective-c pointer types 4582/// for assignment compatibility. 4583Sema::AssignConvertType 4584Sema::CheckObjCPointerTypesForAssignment(QualType lhsType, QualType rhsType) { 4585 if (lhsType->isObjCBuiltinType() || rhsType->isObjCBuiltinType()) 4586 return Compatible; 4587 QualType lhptee = 4588 lhsType->getAs<ObjCObjectPointerType>()->getPointeeType(); 4589 QualType rhptee = 4590 rhsType->getAs<ObjCObjectPointerType>()->getPointeeType(); 4591 // make sure we operate on the canonical type 4592 lhptee = Context.getCanonicalType(lhptee); 4593 rhptee = Context.getCanonicalType(rhptee); 4594 if (!lhptee.isAtLeastAsQualifiedAs(rhptee)) 4595 return CompatiblePointerDiscardsQualifiers; 4596 4597 if (Context.typesAreCompatible(lhsType, rhsType)) 4598 return Compatible; 4599 if (lhsType->isObjCQualifiedIdType() || rhsType->isObjCQualifiedIdType()) 4600 return IncompatibleObjCQualifiedId; 4601 return IncompatiblePointer; 4602} 4603 4604/// CheckAssignmentConstraints (C99 6.5.16) - This routine currently 4605/// has code to accommodate several GCC extensions when type checking 4606/// pointers. Here are some objectionable examples that GCC considers warnings: 4607/// 4608/// int a, *pint; 4609/// short *pshort; 4610/// struct foo *pfoo; 4611/// 4612/// pint = pshort; // warning: assignment from incompatible pointer type 4613/// a = pint; // warning: assignment makes integer from pointer without a cast 4614/// pint = a; // warning: assignment makes pointer from integer without a cast 4615/// pint = pfoo; // warning: assignment from incompatible pointer type 4616/// 4617/// As a result, the code for dealing with pointers is more complex than the 4618/// C99 spec dictates. 4619/// 4620Sema::AssignConvertType 4621Sema::CheckAssignmentConstraints(QualType lhsType, QualType rhsType) { 4622 // Get canonical types. We're not formatting these types, just comparing 4623 // them. 4624 lhsType = Context.getCanonicalType(lhsType).getUnqualifiedType(); 4625 rhsType = Context.getCanonicalType(rhsType).getUnqualifiedType(); 4626 4627 if (lhsType == rhsType) 4628 return Compatible; // Common case: fast path an exact match. 4629 4630 if ((lhsType->isObjCClassType() && 4631 (rhsType.getDesugaredType() == Context.ObjCClassRedefinitionType)) || 4632 (rhsType->isObjCClassType() && 4633 (lhsType.getDesugaredType() == Context.ObjCClassRedefinitionType))) { 4634 return Compatible; 4635 } 4636 4637 // If the left-hand side is a reference type, then we are in a 4638 // (rare!) case where we've allowed the use of references in C, 4639 // e.g., as a parameter type in a built-in function. In this case, 4640 // just make sure that the type referenced is compatible with the 4641 // right-hand side type. The caller is responsible for adjusting 4642 // lhsType so that the resulting expression does not have reference 4643 // type. 4644 if (const ReferenceType *lhsTypeRef = lhsType->getAs<ReferenceType>()) { 4645 if (Context.typesAreCompatible(lhsTypeRef->getPointeeType(), rhsType)) 4646 return Compatible; 4647 return Incompatible; 4648 } 4649 // Allow scalar to ExtVector assignments, and assignments of an ExtVector type 4650 // to the same ExtVector type. 4651 if (lhsType->isExtVectorType()) { 4652 if (rhsType->isExtVectorType()) 4653 return lhsType == rhsType ? Compatible : Incompatible; 4654 if (!rhsType->isVectorType() && rhsType->isArithmeticType()) 4655 return Compatible; 4656 } 4657 4658 if (lhsType->isVectorType() || rhsType->isVectorType()) { 4659 // If we are allowing lax vector conversions, and LHS and RHS are both 4660 // vectors, the total size only needs to be the same. This is a bitcast; 4661 // no bits are changed but the result type is different. 4662 if (getLangOptions().LaxVectorConversions && 4663 lhsType->isVectorType() && rhsType->isVectorType()) { 4664 if (Context.getTypeSize(lhsType) == Context.getTypeSize(rhsType)) 4665 return IncompatibleVectors; 4666 } 4667 return Incompatible; 4668 } 4669 4670 if (lhsType->isArithmeticType() && rhsType->isArithmeticType()) 4671 return Compatible; 4672 4673 if (isa<PointerType>(lhsType)) { 4674 if (rhsType->isIntegerType()) 4675 return IntToPointer; 4676 4677 if (isa<PointerType>(rhsType)) 4678 return CheckPointerTypesForAssignment(lhsType, rhsType); 4679 4680 // In general, C pointers are not compatible with ObjC object pointers. 4681 if (isa<ObjCObjectPointerType>(rhsType)) { 4682 if (lhsType->isVoidPointerType()) // an exception to the rule. 4683 return Compatible; 4684 return IncompatiblePointer; 4685 } 4686 if (rhsType->getAs<BlockPointerType>()) { 4687 if (lhsType->getAs<PointerType>()->getPointeeType()->isVoidType()) 4688 return Compatible; 4689 4690 // Treat block pointers as objects. 4691 if (getLangOptions().ObjC1 && lhsType->isObjCIdType()) 4692 return Compatible; 4693 } 4694 return Incompatible; 4695 } 4696 4697 if (isa<BlockPointerType>(lhsType)) { 4698 if (rhsType->isIntegerType()) 4699 return IntToBlockPointer; 4700 4701 // Treat block pointers as objects. 4702 if (getLangOptions().ObjC1 && rhsType->isObjCIdType()) 4703 return Compatible; 4704 4705 if (rhsType->isBlockPointerType()) 4706 return CheckBlockPointerTypesForAssignment(lhsType, rhsType); 4707 4708 if (const PointerType *RHSPT = rhsType->getAs<PointerType>()) { 4709 if (RHSPT->getPointeeType()->isVoidType()) 4710 return Compatible; 4711 } 4712 return Incompatible; 4713 } 4714 4715 if (isa<ObjCObjectPointerType>(lhsType)) { 4716 if (rhsType->isIntegerType()) 4717 return IntToPointer; 4718 4719 // In general, C pointers are not compatible with ObjC object pointers. 4720 if (isa<PointerType>(rhsType)) { 4721 if (rhsType->isVoidPointerType()) // an exception to the rule. 4722 return Compatible; 4723 return IncompatiblePointer; 4724 } 4725 if (rhsType->isObjCObjectPointerType()) { 4726 return CheckObjCPointerTypesForAssignment(lhsType, rhsType); 4727 } 4728 if (const PointerType *RHSPT = rhsType->getAs<PointerType>()) { 4729 if (RHSPT->getPointeeType()->isVoidType()) 4730 return Compatible; 4731 } 4732 // Treat block pointers as objects. 4733 if (rhsType->isBlockPointerType()) 4734 return Compatible; 4735 return Incompatible; 4736 } 4737 if (isa<PointerType>(rhsType)) { 4738 // C99 6.5.16.1p1: the left operand is _Bool and the right is a pointer. 4739 if (lhsType == Context.BoolTy) 4740 return Compatible; 4741 4742 if (lhsType->isIntegerType()) 4743 return PointerToInt; 4744 4745 if (isa<PointerType>(lhsType)) 4746 return CheckPointerTypesForAssignment(lhsType, rhsType); 4747 4748 if (isa<BlockPointerType>(lhsType) && 4749 rhsType->getAs<PointerType>()->getPointeeType()->isVoidType()) 4750 return Compatible; 4751 return Incompatible; 4752 } 4753 if (isa<ObjCObjectPointerType>(rhsType)) { 4754 // C99 6.5.16.1p1: the left operand is _Bool and the right is a pointer. 4755 if (lhsType == Context.BoolTy) 4756 return Compatible; 4757 4758 if (lhsType->isIntegerType()) 4759 return PointerToInt; 4760 4761 // In general, C pointers are not compatible with ObjC object pointers. 4762 if (isa<PointerType>(lhsType)) { 4763 if (lhsType->isVoidPointerType()) // an exception to the rule. 4764 return Compatible; 4765 return IncompatiblePointer; 4766 } 4767 if (isa<BlockPointerType>(lhsType) && 4768 rhsType->getAs<PointerType>()->getPointeeType()->isVoidType()) 4769 return Compatible; 4770 return Incompatible; 4771 } 4772 4773 if (isa<TagType>(lhsType) && isa<TagType>(rhsType)) { 4774 if (Context.typesAreCompatible(lhsType, rhsType)) 4775 return Compatible; 4776 } 4777 return Incompatible; 4778} 4779 4780/// \brief Constructs a transparent union from an expression that is 4781/// used to initialize the transparent union. 4782static void ConstructTransparentUnion(ASTContext &C, Expr *&E, 4783 QualType UnionType, FieldDecl *Field) { 4784 // Build an initializer list that designates the appropriate member 4785 // of the transparent union. 4786 InitListExpr *Initializer = new (C) InitListExpr(SourceLocation(), 4787 &E, 1, 4788 SourceLocation()); 4789 Initializer->setType(UnionType); 4790 Initializer->setInitializedFieldInUnion(Field); 4791 4792 // Build a compound literal constructing a value of the transparent 4793 // union type from this initializer list. 4794 TypeSourceInfo *unionTInfo = C.getTrivialTypeSourceInfo(UnionType); 4795 E = new (C) CompoundLiteralExpr(SourceLocation(), unionTInfo, UnionType, 4796 Initializer, false); 4797} 4798 4799Sema::AssignConvertType 4800Sema::CheckTransparentUnionArgumentConstraints(QualType ArgType, Expr *&rExpr) { 4801 QualType FromType = rExpr->getType(); 4802 4803 // If the ArgType is a Union type, we want to handle a potential 4804 // transparent_union GCC extension. 4805 const RecordType *UT = ArgType->getAsUnionType(); 4806 if (!UT || !UT->getDecl()->hasAttr<TransparentUnionAttr>()) 4807 return Incompatible; 4808 4809 // The field to initialize within the transparent union. 4810 RecordDecl *UD = UT->getDecl(); 4811 FieldDecl *InitField = 0; 4812 // It's compatible if the expression matches any of the fields. 4813 for (RecordDecl::field_iterator it = UD->field_begin(), 4814 itend = UD->field_end(); 4815 it != itend; ++it) { 4816 if (it->getType()->isPointerType()) { 4817 // If the transparent union contains a pointer type, we allow: 4818 // 1) void pointer 4819 // 2) null pointer constant 4820 if (FromType->isPointerType()) 4821 if (FromType->getAs<PointerType>()->getPointeeType()->isVoidType()) { 4822 ImpCastExprToType(rExpr, it->getType(), CastExpr::CK_BitCast); 4823 InitField = *it; 4824 break; 4825 } 4826 4827 if (rExpr->isNullPointerConstant(Context, 4828 Expr::NPC_ValueDependentIsNull)) { 4829 ImpCastExprToType(rExpr, it->getType(), CastExpr::CK_IntegralToPointer); 4830 InitField = *it; 4831 break; 4832 } 4833 } 4834 4835 if (CheckAssignmentConstraints(it->getType(), rExpr->getType()) 4836 == Compatible) { 4837 InitField = *it; 4838 break; 4839 } 4840 } 4841 4842 if (!InitField) 4843 return Incompatible; 4844 4845 ConstructTransparentUnion(Context, rExpr, ArgType, InitField); 4846 return Compatible; 4847} 4848 4849Sema::AssignConvertType 4850Sema::CheckSingleAssignmentConstraints(QualType lhsType, Expr *&rExpr) { 4851 if (getLangOptions().CPlusPlus) { 4852 if (!lhsType->isRecordType()) { 4853 // C++ 5.17p3: If the left operand is not of class type, the 4854 // expression is implicitly converted (C++ 4) to the 4855 // cv-unqualified type of the left operand. 4856 if (PerformImplicitConversion(rExpr, lhsType.getUnqualifiedType(), 4857 AA_Assigning)) 4858 return Incompatible; 4859 return Compatible; 4860 } 4861 4862 // FIXME: Currently, we fall through and treat C++ classes like C 4863 // structures. 4864 } 4865 4866 // C99 6.5.16.1p1: the left operand is a pointer and the right is 4867 // a null pointer constant. 4868 if ((lhsType->isPointerType() || 4869 lhsType->isObjCObjectPointerType() || 4870 lhsType->isBlockPointerType()) 4871 && rExpr->isNullPointerConstant(Context, 4872 Expr::NPC_ValueDependentIsNull)) { 4873 ImpCastExprToType(rExpr, lhsType, CastExpr::CK_Unknown); 4874 return Compatible; 4875 } 4876 4877 // This check seems unnatural, however it is necessary to ensure the proper 4878 // conversion of functions/arrays. If the conversion were done for all 4879 // DeclExpr's (created by ActOnIdExpression), it would mess up the unary 4880 // expressions that surpress this implicit conversion (&, sizeof). 4881 // 4882 // Suppress this for references: C++ 8.5.3p5. 4883 if (!lhsType->isReferenceType()) 4884 DefaultFunctionArrayLvalueConversion(rExpr); 4885 4886 Sema::AssignConvertType result = 4887 CheckAssignmentConstraints(lhsType, rExpr->getType()); 4888 4889 // C99 6.5.16.1p2: The value of the right operand is converted to the 4890 // type of the assignment expression. 4891 // CheckAssignmentConstraints allows the left-hand side to be a reference, 4892 // so that we can use references in built-in functions even in C. 4893 // The getNonReferenceType() call makes sure that the resulting expression 4894 // does not have reference type. 4895 if (result != Incompatible && rExpr->getType() != lhsType) 4896 ImpCastExprToType(rExpr, lhsType.getNonReferenceType(), 4897 CastExpr::CK_Unknown); 4898 return result; 4899} 4900 4901QualType Sema::InvalidOperands(SourceLocation Loc, Expr *&lex, Expr *&rex) { 4902 Diag(Loc, diag::err_typecheck_invalid_operands) 4903 << lex->getType() << rex->getType() 4904 << lex->getSourceRange() << rex->getSourceRange(); 4905 return QualType(); 4906} 4907 4908QualType Sema::CheckVectorOperands(SourceLocation Loc, Expr *&lex, Expr *&rex) { 4909 // For conversion purposes, we ignore any qualifiers. 4910 // For example, "const float" and "float" are equivalent. 4911 QualType lhsType = 4912 Context.getCanonicalType(lex->getType()).getUnqualifiedType(); 4913 QualType rhsType = 4914 Context.getCanonicalType(rex->getType()).getUnqualifiedType(); 4915 4916 // If the vector types are identical, return. 4917 if (lhsType == rhsType) 4918 return lhsType; 4919 4920 // Handle the case of a vector & extvector type of the same size and element 4921 // type. It would be nice if we only had one vector type someday. 4922 if (getLangOptions().LaxVectorConversions) { 4923 // FIXME: Should we warn here? 4924 if (const VectorType *LV = lhsType->getAs<VectorType>()) { 4925 if (const VectorType *RV = rhsType->getAs<VectorType>()) 4926 if (LV->getElementType() == RV->getElementType() && 4927 LV->getNumElements() == RV->getNumElements()) { 4928 return lhsType->isExtVectorType() ? lhsType : rhsType; 4929 } 4930 } 4931 } 4932 4933 // Canonicalize the ExtVector to the LHS, remember if we swapped so we can 4934 // swap back (so that we don't reverse the inputs to a subtract, for instance. 4935 bool swapped = false; 4936 if (rhsType->isExtVectorType()) { 4937 swapped = true; 4938 std::swap(rex, lex); 4939 std::swap(rhsType, lhsType); 4940 } 4941 4942 // Handle the case of an ext vector and scalar. 4943 if (const ExtVectorType *LV = lhsType->getAs<ExtVectorType>()) { 4944 QualType EltTy = LV->getElementType(); 4945 if (EltTy->isIntegralType() && rhsType->isIntegralType()) { 4946 if (Context.getIntegerTypeOrder(EltTy, rhsType) >= 0) { 4947 ImpCastExprToType(rex, lhsType, CastExpr::CK_IntegralCast); 4948 if (swapped) std::swap(rex, lex); 4949 return lhsType; 4950 } 4951 } 4952 if (EltTy->isRealFloatingType() && rhsType->isScalarType() && 4953 rhsType->isRealFloatingType()) { 4954 if (Context.getFloatingTypeOrder(EltTy, rhsType) >= 0) { 4955 ImpCastExprToType(rex, lhsType, CastExpr::CK_FloatingCast); 4956 if (swapped) std::swap(rex, lex); 4957 return lhsType; 4958 } 4959 } 4960 } 4961 4962 // Vectors of different size or scalar and non-ext-vector are errors. 4963 Diag(Loc, diag::err_typecheck_vector_not_convertable) 4964 << lex->getType() << rex->getType() 4965 << lex->getSourceRange() << rex->getSourceRange(); 4966 return QualType(); 4967} 4968 4969QualType Sema::CheckMultiplyDivideOperands( 4970 Expr *&lex, Expr *&rex, SourceLocation Loc, bool isCompAssign, bool isDiv) { 4971 if (lex->getType()->isVectorType() || rex->getType()->isVectorType()) 4972 return CheckVectorOperands(Loc, lex, rex); 4973 4974 QualType compType = UsualArithmeticConversions(lex, rex, isCompAssign); 4975 4976 if (!lex->getType()->isArithmeticType() || 4977 !rex->getType()->isArithmeticType()) 4978 return InvalidOperands(Loc, lex, rex); 4979 4980 // Check for division by zero. 4981 if (isDiv && 4982 rex->isNullPointerConstant(Context, Expr::NPC_ValueDependentIsNotNull)) 4983 DiagRuntimeBehavior(Loc, PDiag(diag::warn_division_by_zero) 4984 << rex->getSourceRange()); 4985 4986 return compType; 4987} 4988 4989QualType Sema::CheckRemainderOperands( 4990 Expr *&lex, Expr *&rex, SourceLocation Loc, bool isCompAssign) { 4991 if (lex->getType()->isVectorType() || rex->getType()->isVectorType()) { 4992 if (lex->getType()->isIntegerType() && rex->getType()->isIntegerType()) 4993 return CheckVectorOperands(Loc, lex, rex); 4994 return InvalidOperands(Loc, lex, rex); 4995 } 4996 4997 QualType compType = UsualArithmeticConversions(lex, rex, isCompAssign); 4998 4999 if (!lex->getType()->isIntegerType() || !rex->getType()->isIntegerType()) 5000 return InvalidOperands(Loc, lex, rex); 5001 5002 // Check for remainder by zero. 5003 if (rex->isNullPointerConstant(Context, Expr::NPC_ValueDependentIsNotNull)) 5004 DiagRuntimeBehavior(Loc, PDiag(diag::warn_remainder_by_zero) 5005 << rex->getSourceRange()); 5006 5007 return compType; 5008} 5009 5010QualType Sema::CheckAdditionOperands( // C99 6.5.6 5011 Expr *&lex, Expr *&rex, SourceLocation Loc, QualType* CompLHSTy) { 5012 if (lex->getType()->isVectorType() || rex->getType()->isVectorType()) { 5013 QualType compType = CheckVectorOperands(Loc, lex, rex); 5014 if (CompLHSTy) *CompLHSTy = compType; 5015 return compType; 5016 } 5017 5018 QualType compType = UsualArithmeticConversions(lex, rex, CompLHSTy); 5019 5020 // handle the common case first (both operands are arithmetic). 5021 if (lex->getType()->isArithmeticType() && 5022 rex->getType()->isArithmeticType()) { 5023 if (CompLHSTy) *CompLHSTy = compType; 5024 return compType; 5025 } 5026 5027 // Put any potential pointer into PExp 5028 Expr* PExp = lex, *IExp = rex; 5029 if (IExp->getType()->isAnyPointerType()) 5030 std::swap(PExp, IExp); 5031 5032 if (PExp->getType()->isAnyPointerType()) { 5033 5034 if (IExp->getType()->isIntegerType()) { 5035 QualType PointeeTy = PExp->getType()->getPointeeType(); 5036 5037 // Check for arithmetic on pointers to incomplete types. 5038 if (PointeeTy->isVoidType()) { 5039 if (getLangOptions().CPlusPlus) { 5040 Diag(Loc, diag::err_typecheck_pointer_arith_void_type) 5041 << lex->getSourceRange() << rex->getSourceRange(); 5042 return QualType(); 5043 } 5044 5045 // GNU extension: arithmetic on pointer to void 5046 Diag(Loc, diag::ext_gnu_void_ptr) 5047 << lex->getSourceRange() << rex->getSourceRange(); 5048 } else if (PointeeTy->isFunctionType()) { 5049 if (getLangOptions().CPlusPlus) { 5050 Diag(Loc, diag::err_typecheck_pointer_arith_function_type) 5051 << lex->getType() << lex->getSourceRange(); 5052 return QualType(); 5053 } 5054 5055 // GNU extension: arithmetic on pointer to function 5056 Diag(Loc, diag::ext_gnu_ptr_func_arith) 5057 << lex->getType() << lex->getSourceRange(); 5058 } else { 5059 // Check if we require a complete type. 5060 if (((PExp->getType()->isPointerType() && 5061 !PExp->getType()->isDependentType()) || 5062 PExp->getType()->isObjCObjectPointerType()) && 5063 RequireCompleteType(Loc, PointeeTy, 5064 PDiag(diag::err_typecheck_arithmetic_incomplete_type) 5065 << PExp->getSourceRange() 5066 << PExp->getType())) 5067 return QualType(); 5068 } 5069 // Diagnose bad cases where we step over interface counts. 5070 if (PointeeTy->isObjCInterfaceType() && LangOpts.ObjCNonFragileABI) { 5071 Diag(Loc, diag::err_arithmetic_nonfragile_interface) 5072 << PointeeTy << PExp->getSourceRange(); 5073 return QualType(); 5074 } 5075 5076 if (CompLHSTy) { 5077 QualType LHSTy = Context.isPromotableBitField(lex); 5078 if (LHSTy.isNull()) { 5079 LHSTy = lex->getType(); 5080 if (LHSTy->isPromotableIntegerType()) 5081 LHSTy = Context.getPromotedIntegerType(LHSTy); 5082 } 5083 *CompLHSTy = LHSTy; 5084 } 5085 return PExp->getType(); 5086 } 5087 } 5088 5089 return InvalidOperands(Loc, lex, rex); 5090} 5091 5092// C99 6.5.6 5093QualType Sema::CheckSubtractionOperands(Expr *&lex, Expr *&rex, 5094 SourceLocation Loc, QualType* CompLHSTy) { 5095 if (lex->getType()->isVectorType() || rex->getType()->isVectorType()) { 5096 QualType compType = CheckVectorOperands(Loc, lex, rex); 5097 if (CompLHSTy) *CompLHSTy = compType; 5098 return compType; 5099 } 5100 5101 QualType compType = UsualArithmeticConversions(lex, rex, CompLHSTy); 5102 5103 // Enforce type constraints: C99 6.5.6p3. 5104 5105 // Handle the common case first (both operands are arithmetic). 5106 if (lex->getType()->isArithmeticType() 5107 && rex->getType()->isArithmeticType()) { 5108 if (CompLHSTy) *CompLHSTy = compType; 5109 return compType; 5110 } 5111 5112 // Either ptr - int or ptr - ptr. 5113 if (lex->getType()->isAnyPointerType()) { 5114 QualType lpointee = lex->getType()->getPointeeType(); 5115 5116 // The LHS must be an completely-defined object type. 5117 5118 bool ComplainAboutVoid = false; 5119 Expr *ComplainAboutFunc = 0; 5120 if (lpointee->isVoidType()) { 5121 if (getLangOptions().CPlusPlus) { 5122 Diag(Loc, diag::err_typecheck_pointer_arith_void_type) 5123 << lex->getSourceRange() << rex->getSourceRange(); 5124 return QualType(); 5125 } 5126 5127 // GNU C extension: arithmetic on pointer to void 5128 ComplainAboutVoid = true; 5129 } else if (lpointee->isFunctionType()) { 5130 if (getLangOptions().CPlusPlus) { 5131 Diag(Loc, diag::err_typecheck_pointer_arith_function_type) 5132 << lex->getType() << lex->getSourceRange(); 5133 return QualType(); 5134 } 5135 5136 // GNU C extension: arithmetic on pointer to function 5137 ComplainAboutFunc = lex; 5138 } else if (!lpointee->isDependentType() && 5139 RequireCompleteType(Loc, lpointee, 5140 PDiag(diag::err_typecheck_sub_ptr_object) 5141 << lex->getSourceRange() 5142 << lex->getType())) 5143 return QualType(); 5144 5145 // Diagnose bad cases where we step over interface counts. 5146 if (lpointee->isObjCInterfaceType() && LangOpts.ObjCNonFragileABI) { 5147 Diag(Loc, diag::err_arithmetic_nonfragile_interface) 5148 << lpointee << lex->getSourceRange(); 5149 return QualType(); 5150 } 5151 5152 // The result type of a pointer-int computation is the pointer type. 5153 if (rex->getType()->isIntegerType()) { 5154 if (ComplainAboutVoid) 5155 Diag(Loc, diag::ext_gnu_void_ptr) 5156 << lex->getSourceRange() << rex->getSourceRange(); 5157 if (ComplainAboutFunc) 5158 Diag(Loc, diag::ext_gnu_ptr_func_arith) 5159 << ComplainAboutFunc->getType() 5160 << ComplainAboutFunc->getSourceRange(); 5161 5162 if (CompLHSTy) *CompLHSTy = lex->getType(); 5163 return lex->getType(); 5164 } 5165 5166 // Handle pointer-pointer subtractions. 5167 if (const PointerType *RHSPTy = rex->getType()->getAs<PointerType>()) { 5168 QualType rpointee = RHSPTy->getPointeeType(); 5169 5170 // RHS must be a completely-type object type. 5171 // Handle the GNU void* extension. 5172 if (rpointee->isVoidType()) { 5173 if (getLangOptions().CPlusPlus) { 5174 Diag(Loc, diag::err_typecheck_pointer_arith_void_type) 5175 << lex->getSourceRange() << rex->getSourceRange(); 5176 return QualType(); 5177 } 5178 5179 ComplainAboutVoid = true; 5180 } else if (rpointee->isFunctionType()) { 5181 if (getLangOptions().CPlusPlus) { 5182 Diag(Loc, diag::err_typecheck_pointer_arith_function_type) 5183 << rex->getType() << rex->getSourceRange(); 5184 return QualType(); 5185 } 5186 5187 // GNU extension: arithmetic on pointer to function 5188 if (!ComplainAboutFunc) 5189 ComplainAboutFunc = rex; 5190 } else if (!rpointee->isDependentType() && 5191 RequireCompleteType(Loc, rpointee, 5192 PDiag(diag::err_typecheck_sub_ptr_object) 5193 << rex->getSourceRange() 5194 << rex->getType())) 5195 return QualType(); 5196 5197 if (getLangOptions().CPlusPlus) { 5198 // Pointee types must be the same: C++ [expr.add] 5199 if (!Context.hasSameUnqualifiedType(lpointee, rpointee)) { 5200 Diag(Loc, diag::err_typecheck_sub_ptr_compatible) 5201 << lex->getType() << rex->getType() 5202 << lex->getSourceRange() << rex->getSourceRange(); 5203 return QualType(); 5204 } 5205 } else { 5206 // Pointee types must be compatible C99 6.5.6p3 5207 if (!Context.typesAreCompatible( 5208 Context.getCanonicalType(lpointee).getUnqualifiedType(), 5209 Context.getCanonicalType(rpointee).getUnqualifiedType())) { 5210 Diag(Loc, diag::err_typecheck_sub_ptr_compatible) 5211 << lex->getType() << rex->getType() 5212 << lex->getSourceRange() << rex->getSourceRange(); 5213 return QualType(); 5214 } 5215 } 5216 5217 if (ComplainAboutVoid) 5218 Diag(Loc, diag::ext_gnu_void_ptr) 5219 << lex->getSourceRange() << rex->getSourceRange(); 5220 if (ComplainAboutFunc) 5221 Diag(Loc, diag::ext_gnu_ptr_func_arith) 5222 << ComplainAboutFunc->getType() 5223 << ComplainAboutFunc->getSourceRange(); 5224 5225 if (CompLHSTy) *CompLHSTy = lex->getType(); 5226 return Context.getPointerDiffType(); 5227 } 5228 } 5229 5230 return InvalidOperands(Loc, lex, rex); 5231} 5232 5233// C99 6.5.7 5234QualType Sema::CheckShiftOperands(Expr *&lex, Expr *&rex, SourceLocation Loc, 5235 bool isCompAssign) { 5236 // C99 6.5.7p2: Each of the operands shall have integer type. 5237 if (!lex->getType()->isIntegerType() || !rex->getType()->isIntegerType()) 5238 return InvalidOperands(Loc, lex, rex); 5239 5240 // Vector shifts promote their scalar inputs to vector type. 5241 if (lex->getType()->isVectorType() || rex->getType()->isVectorType()) 5242 return CheckVectorOperands(Loc, lex, rex); 5243 5244 // Shifts don't perform usual arithmetic conversions, they just do integer 5245 // promotions on each operand. C99 6.5.7p3 5246 QualType LHSTy = Context.isPromotableBitField(lex); 5247 if (LHSTy.isNull()) { 5248 LHSTy = lex->getType(); 5249 if (LHSTy->isPromotableIntegerType()) 5250 LHSTy = Context.getPromotedIntegerType(LHSTy); 5251 } 5252 if (!isCompAssign) 5253 ImpCastExprToType(lex, LHSTy, CastExpr::CK_IntegralCast); 5254 5255 UsualUnaryConversions(rex); 5256 5257 // Sanity-check shift operands 5258 llvm::APSInt Right; 5259 // Check right/shifter operand 5260 if (!rex->isValueDependent() && 5261 rex->isIntegerConstantExpr(Right, Context)) { 5262 if (Right.isNegative()) 5263 Diag(Loc, diag::warn_shift_negative) << rex->getSourceRange(); 5264 else { 5265 llvm::APInt LeftBits(Right.getBitWidth(), 5266 Context.getTypeSize(lex->getType())); 5267 if (Right.uge(LeftBits)) 5268 Diag(Loc, diag::warn_shift_gt_typewidth) << rex->getSourceRange(); 5269 } 5270 } 5271 5272 // "The type of the result is that of the promoted left operand." 5273 return LHSTy; 5274} 5275 5276// C99 6.5.8, C++ [expr.rel] 5277QualType Sema::CheckCompareOperands(Expr *&lex, Expr *&rex, SourceLocation Loc, 5278 unsigned OpaqueOpc, bool isRelational) { 5279 BinaryOperator::Opcode Opc = (BinaryOperator::Opcode)OpaqueOpc; 5280 5281 // Handle vector comparisons separately. 5282 if (lex->getType()->isVectorType() || rex->getType()->isVectorType()) 5283 return CheckVectorCompareOperands(lex, rex, Loc, isRelational); 5284 5285 CheckSignCompare(lex, rex, Loc, &Opc); 5286 5287 // C99 6.5.8p3 / C99 6.5.9p4 5288 if (lex->getType()->isArithmeticType() && rex->getType()->isArithmeticType()) 5289 UsualArithmeticConversions(lex, rex); 5290 else { 5291 UsualUnaryConversions(lex); 5292 UsualUnaryConversions(rex); 5293 } 5294 QualType lType = lex->getType(); 5295 QualType rType = rex->getType(); 5296 5297 if (!lType->isFloatingType() 5298 && !(lType->isBlockPointerType() && isRelational)) { 5299 // For non-floating point types, check for self-comparisons of the form 5300 // x == x, x != x, x < x, etc. These always evaluate to a constant, and 5301 // often indicate logic errors in the program. 5302 // NOTE: Don't warn about comparisons of enum constants. These can arise 5303 // from macro expansions, and are usually quite deliberate. 5304 Expr *LHSStripped = lex->IgnoreParens(); 5305 Expr *RHSStripped = rex->IgnoreParens(); 5306 if (DeclRefExpr* DRL = dyn_cast<DeclRefExpr>(LHSStripped)) 5307 if (DeclRefExpr* DRR = dyn_cast<DeclRefExpr>(RHSStripped)) 5308 if (DRL->getDecl() == DRR->getDecl() && 5309 !isa<EnumConstantDecl>(DRL->getDecl())) 5310 DiagRuntimeBehavior(Loc, PDiag(diag::warn_selfcomparison)); 5311 5312 if (isa<CastExpr>(LHSStripped)) 5313 LHSStripped = LHSStripped->IgnoreParenCasts(); 5314 if (isa<CastExpr>(RHSStripped)) 5315 RHSStripped = RHSStripped->IgnoreParenCasts(); 5316 5317 // Warn about comparisons against a string constant (unless the other 5318 // operand is null), the user probably wants strcmp. 5319 Expr *literalString = 0; 5320 Expr *literalStringStripped = 0; 5321 if ((isa<StringLiteral>(LHSStripped) || isa<ObjCEncodeExpr>(LHSStripped)) && 5322 !RHSStripped->isNullPointerConstant(Context, 5323 Expr::NPC_ValueDependentIsNull)) { 5324 literalString = lex; 5325 literalStringStripped = LHSStripped; 5326 } else if ((isa<StringLiteral>(RHSStripped) || 5327 isa<ObjCEncodeExpr>(RHSStripped)) && 5328 !LHSStripped->isNullPointerConstant(Context, 5329 Expr::NPC_ValueDependentIsNull)) { 5330 literalString = rex; 5331 literalStringStripped = RHSStripped; 5332 } 5333 5334 if (literalString) { 5335 std::string resultComparison; 5336 switch (Opc) { 5337 case BinaryOperator::LT: resultComparison = ") < 0"; break; 5338 case BinaryOperator::GT: resultComparison = ") > 0"; break; 5339 case BinaryOperator::LE: resultComparison = ") <= 0"; break; 5340 case BinaryOperator::GE: resultComparison = ") >= 0"; break; 5341 case BinaryOperator::EQ: resultComparison = ") == 0"; break; 5342 case BinaryOperator::NE: resultComparison = ") != 0"; break; 5343 default: assert(false && "Invalid comparison operator"); 5344 } 5345 5346 DiagRuntimeBehavior(Loc, 5347 PDiag(diag::warn_stringcompare) 5348 << isa<ObjCEncodeExpr>(literalStringStripped) 5349 << literalString->getSourceRange() 5350 << CodeModificationHint::CreateReplacement(SourceRange(Loc), ", ") 5351 << CodeModificationHint::CreateInsertion(lex->getLocStart(), 5352 "strcmp(") 5353 << CodeModificationHint::CreateInsertion( 5354 PP.getLocForEndOfToken(rex->getLocEnd()), 5355 resultComparison)); 5356 } 5357 } 5358 5359 // The result of comparisons is 'bool' in C++, 'int' in C. 5360 QualType ResultTy = getLangOptions().CPlusPlus ? Context.BoolTy:Context.IntTy; 5361 5362 if (isRelational) { 5363 if (lType->isRealType() && rType->isRealType()) 5364 return ResultTy; 5365 } else { 5366 // Check for comparisons of floating point operands using != and ==. 5367 if (lType->isFloatingType() && rType->isFloatingType()) 5368 CheckFloatComparison(Loc,lex,rex); 5369 5370 if (lType->isArithmeticType() && rType->isArithmeticType()) 5371 return ResultTy; 5372 } 5373 5374 bool LHSIsNull = lex->isNullPointerConstant(Context, 5375 Expr::NPC_ValueDependentIsNull); 5376 bool RHSIsNull = rex->isNullPointerConstant(Context, 5377 Expr::NPC_ValueDependentIsNull); 5378 5379 // All of the following pointer related warnings are GCC extensions, except 5380 // when handling null pointer constants. One day, we can consider making them 5381 // errors (when -pedantic-errors is enabled). 5382 if (lType->isPointerType() && rType->isPointerType()) { // C99 6.5.8p2 5383 QualType LCanPointeeTy = 5384 Context.getCanonicalType(lType->getAs<PointerType>()->getPointeeType()); 5385 QualType RCanPointeeTy = 5386 Context.getCanonicalType(rType->getAs<PointerType>()->getPointeeType()); 5387 5388 if (getLangOptions().CPlusPlus) { 5389 if (LCanPointeeTy == RCanPointeeTy) 5390 return ResultTy; 5391 if (!isRelational && 5392 (LCanPointeeTy->isVoidType() || RCanPointeeTy->isVoidType())) { 5393 // Valid unless comparison between non-null pointer and function pointer 5394 // This is a gcc extension compatibility comparison. 5395 if ((LCanPointeeTy->isFunctionType() || RCanPointeeTy->isFunctionType()) 5396 && !LHSIsNull && !RHSIsNull) { 5397 Diag(Loc, diag::ext_typecheck_comparison_of_fptr_to_void) 5398 << lType << rType << lex->getSourceRange() << rex->getSourceRange(); 5399 ImpCastExprToType(rex, lType, CastExpr::CK_BitCast); 5400 return ResultTy; 5401 } 5402 } 5403 // C++ [expr.rel]p2: 5404 // [...] Pointer conversions (4.10) and qualification 5405 // conversions (4.4) are performed on pointer operands (or on 5406 // a pointer operand and a null pointer constant) to bring 5407 // them to their composite pointer type. [...] 5408 // 5409 // C++ [expr.eq]p1 uses the same notion for (in)equality 5410 // comparisons of pointers. 5411 bool NonStandardCompositeType = false; 5412 QualType T = FindCompositePointerType(lex, rex, 5413 isSFINAEContext()? 0 : &NonStandardCompositeType); 5414 if (T.isNull()) { 5415 Diag(Loc, diag::err_typecheck_comparison_of_distinct_pointers) 5416 << lType << rType << lex->getSourceRange() << rex->getSourceRange(); 5417 return QualType(); 5418 } else if (NonStandardCompositeType) { 5419 Diag(Loc, 5420 diag::ext_typecheck_comparison_of_distinct_pointers_nonstandard) 5421 << lType << rType << T 5422 << lex->getSourceRange() << rex->getSourceRange(); 5423 } 5424 5425 ImpCastExprToType(lex, T, CastExpr::CK_BitCast); 5426 ImpCastExprToType(rex, T, CastExpr::CK_BitCast); 5427 return ResultTy; 5428 } 5429 // C99 6.5.9p2 and C99 6.5.8p2 5430 if (Context.typesAreCompatible(LCanPointeeTy.getUnqualifiedType(), 5431 RCanPointeeTy.getUnqualifiedType())) { 5432 // Valid unless a relational comparison of function pointers 5433 if (isRelational && LCanPointeeTy->isFunctionType()) { 5434 Diag(Loc, diag::ext_typecheck_ordered_comparison_of_function_pointers) 5435 << lType << rType << lex->getSourceRange() << rex->getSourceRange(); 5436 } 5437 } else if (!isRelational && 5438 (LCanPointeeTy->isVoidType() || RCanPointeeTy->isVoidType())) { 5439 // Valid unless comparison between non-null pointer and function pointer 5440 if ((LCanPointeeTy->isFunctionType() || RCanPointeeTy->isFunctionType()) 5441 && !LHSIsNull && !RHSIsNull) { 5442 Diag(Loc, diag::ext_typecheck_comparison_of_fptr_to_void) 5443 << lType << rType << lex->getSourceRange() << rex->getSourceRange(); 5444 } 5445 } else { 5446 // Invalid 5447 Diag(Loc, diag::ext_typecheck_comparison_of_distinct_pointers) 5448 << lType << rType << lex->getSourceRange() << rex->getSourceRange(); 5449 } 5450 if (LCanPointeeTy != RCanPointeeTy) 5451 ImpCastExprToType(rex, lType, CastExpr::CK_BitCast); 5452 return ResultTy; 5453 } 5454 5455 if (getLangOptions().CPlusPlus) { 5456 // Comparison of pointers with null pointer constants and equality 5457 // comparisons of member pointers to null pointer constants. 5458 if (RHSIsNull && 5459 (lType->isPointerType() || 5460 (!isRelational && lType->isMemberPointerType()))) { 5461 ImpCastExprToType(rex, lType, CastExpr::CK_NullToMemberPointer); 5462 return ResultTy; 5463 } 5464 if (LHSIsNull && 5465 (rType->isPointerType() || 5466 (!isRelational && rType->isMemberPointerType()))) { 5467 ImpCastExprToType(lex, rType, CastExpr::CK_NullToMemberPointer); 5468 return ResultTy; 5469 } 5470 5471 // Comparison of member pointers. 5472 if (!isRelational && 5473 lType->isMemberPointerType() && rType->isMemberPointerType()) { 5474 // C++ [expr.eq]p2: 5475 // In addition, pointers to members can be compared, or a pointer to 5476 // member and a null pointer constant. Pointer to member conversions 5477 // (4.11) and qualification conversions (4.4) are performed to bring 5478 // them to a common type. If one operand is a null pointer constant, 5479 // the common type is the type of the other operand. Otherwise, the 5480 // common type is a pointer to member type similar (4.4) to the type 5481 // of one of the operands, with a cv-qualification signature (4.4) 5482 // that is the union of the cv-qualification signatures of the operand 5483 // types. 5484 bool NonStandardCompositeType = false; 5485 QualType T = FindCompositePointerType(lex, rex, 5486 isSFINAEContext()? 0 : &NonStandardCompositeType); 5487 if (T.isNull()) { 5488 Diag(Loc, diag::err_typecheck_comparison_of_distinct_pointers) 5489 << lType << rType << lex->getSourceRange() << rex->getSourceRange(); 5490 return QualType(); 5491 } else if (NonStandardCompositeType) { 5492 Diag(Loc, 5493 diag::ext_typecheck_comparison_of_distinct_pointers_nonstandard) 5494 << lType << rType << T 5495 << lex->getSourceRange() << rex->getSourceRange(); 5496 } 5497 5498 ImpCastExprToType(lex, T, CastExpr::CK_BitCast); 5499 ImpCastExprToType(rex, T, CastExpr::CK_BitCast); 5500 return ResultTy; 5501 } 5502 5503 // Comparison of nullptr_t with itself. 5504 if (lType->isNullPtrType() && rType->isNullPtrType()) 5505 return ResultTy; 5506 } 5507 5508 // Handle block pointer types. 5509 if (!isRelational && lType->isBlockPointerType() && rType->isBlockPointerType()) { 5510 QualType lpointee = lType->getAs<BlockPointerType>()->getPointeeType(); 5511 QualType rpointee = rType->getAs<BlockPointerType>()->getPointeeType(); 5512 5513 if (!LHSIsNull && !RHSIsNull && 5514 !Context.typesAreCompatible(lpointee, rpointee)) { 5515 Diag(Loc, diag::err_typecheck_comparison_of_distinct_blocks) 5516 << lType << rType << lex->getSourceRange() << rex->getSourceRange(); 5517 } 5518 ImpCastExprToType(rex, lType, CastExpr::CK_BitCast); 5519 return ResultTy; 5520 } 5521 // Allow block pointers to be compared with null pointer constants. 5522 if (!isRelational 5523 && ((lType->isBlockPointerType() && rType->isPointerType()) 5524 || (lType->isPointerType() && rType->isBlockPointerType()))) { 5525 if (!LHSIsNull && !RHSIsNull) { 5526 if (!((rType->isPointerType() && rType->getAs<PointerType>() 5527 ->getPointeeType()->isVoidType()) 5528 || (lType->isPointerType() && lType->getAs<PointerType>() 5529 ->getPointeeType()->isVoidType()))) 5530 Diag(Loc, diag::err_typecheck_comparison_of_distinct_blocks) 5531 << lType << rType << lex->getSourceRange() << rex->getSourceRange(); 5532 } 5533 ImpCastExprToType(rex, lType, CastExpr::CK_BitCast); 5534 return ResultTy; 5535 } 5536 5537 if ((lType->isObjCObjectPointerType() || rType->isObjCObjectPointerType())) { 5538 if (lType->isPointerType() || rType->isPointerType()) { 5539 const PointerType *LPT = lType->getAs<PointerType>(); 5540 const PointerType *RPT = rType->getAs<PointerType>(); 5541 bool LPtrToVoid = LPT ? 5542 Context.getCanonicalType(LPT->getPointeeType())->isVoidType() : false; 5543 bool RPtrToVoid = RPT ? 5544 Context.getCanonicalType(RPT->getPointeeType())->isVoidType() : false; 5545 5546 if (!LPtrToVoid && !RPtrToVoid && 5547 !Context.typesAreCompatible(lType, rType)) { 5548 Diag(Loc, diag::ext_typecheck_comparison_of_distinct_pointers) 5549 << lType << rType << lex->getSourceRange() << rex->getSourceRange(); 5550 } 5551 ImpCastExprToType(rex, lType, CastExpr::CK_BitCast); 5552 return ResultTy; 5553 } 5554 if (lType->isObjCObjectPointerType() && rType->isObjCObjectPointerType()) { 5555 if (!Context.areComparableObjCPointerTypes(lType, rType)) 5556 Diag(Loc, diag::ext_typecheck_comparison_of_distinct_pointers) 5557 << lType << rType << lex->getSourceRange() << rex->getSourceRange(); 5558 ImpCastExprToType(rex, lType, CastExpr::CK_BitCast); 5559 return ResultTy; 5560 } 5561 } 5562 if (lType->isAnyPointerType() && rType->isIntegerType()) { 5563 unsigned DiagID = 0; 5564 if (RHSIsNull) { 5565 if (isRelational) 5566 DiagID = diag::ext_typecheck_ordered_comparison_of_pointer_and_zero; 5567 } else if (isRelational) 5568 DiagID = diag::ext_typecheck_ordered_comparison_of_pointer_integer; 5569 else 5570 DiagID = diag::ext_typecheck_comparison_of_pointer_integer; 5571 5572 if (DiagID) { 5573 Diag(Loc, DiagID) 5574 << lType << rType << lex->getSourceRange() << rex->getSourceRange(); 5575 } 5576 ImpCastExprToType(rex, lType, CastExpr::CK_IntegralToPointer); 5577 return ResultTy; 5578 } 5579 if (lType->isIntegerType() && rType->isAnyPointerType()) { 5580 unsigned DiagID = 0; 5581 if (LHSIsNull) { 5582 if (isRelational) 5583 DiagID = diag::ext_typecheck_ordered_comparison_of_pointer_and_zero; 5584 } else if (isRelational) 5585 DiagID = diag::ext_typecheck_ordered_comparison_of_pointer_integer; 5586 else 5587 DiagID = diag::ext_typecheck_comparison_of_pointer_integer; 5588 5589 if (DiagID) { 5590 Diag(Loc, DiagID) 5591 << lType << rType << lex->getSourceRange() << rex->getSourceRange(); 5592 } 5593 ImpCastExprToType(lex, rType, CastExpr::CK_IntegralToPointer); 5594 return ResultTy; 5595 } 5596 // Handle block pointers. 5597 if (!isRelational && RHSIsNull 5598 && lType->isBlockPointerType() && rType->isIntegerType()) { 5599 ImpCastExprToType(rex, lType, CastExpr::CK_IntegralToPointer); 5600 return ResultTy; 5601 } 5602 if (!isRelational && LHSIsNull 5603 && lType->isIntegerType() && rType->isBlockPointerType()) { 5604 ImpCastExprToType(lex, rType, CastExpr::CK_IntegralToPointer); 5605 return ResultTy; 5606 } 5607 return InvalidOperands(Loc, lex, rex); 5608} 5609 5610/// CheckVectorCompareOperands - vector comparisons are a clang extension that 5611/// operates on extended vector types. Instead of producing an IntTy result, 5612/// like a scalar comparison, a vector comparison produces a vector of integer 5613/// types. 5614QualType Sema::CheckVectorCompareOperands(Expr *&lex, Expr *&rex, 5615 SourceLocation Loc, 5616 bool isRelational) { 5617 // Check to make sure we're operating on vectors of the same type and width, 5618 // Allowing one side to be a scalar of element type. 5619 QualType vType = CheckVectorOperands(Loc, lex, rex); 5620 if (vType.isNull()) 5621 return vType; 5622 5623 QualType lType = lex->getType(); 5624 QualType rType = rex->getType(); 5625 5626 // For non-floating point types, check for self-comparisons of the form 5627 // x == x, x != x, x < x, etc. These always evaluate to a constant, and 5628 // often indicate logic errors in the program. 5629 if (!lType->isFloatingType()) { 5630 if (DeclRefExpr* DRL = dyn_cast<DeclRefExpr>(lex->IgnoreParens())) 5631 if (DeclRefExpr* DRR = dyn_cast<DeclRefExpr>(rex->IgnoreParens())) 5632 if (DRL->getDecl() == DRR->getDecl()) 5633 DiagRuntimeBehavior(Loc, PDiag(diag::warn_selfcomparison)); 5634 } 5635 5636 // Check for comparisons of floating point operands using != and ==. 5637 if (!isRelational && lType->isFloatingType()) { 5638 assert (rType->isFloatingType()); 5639 CheckFloatComparison(Loc,lex,rex); 5640 } 5641 5642 // Return the type for the comparison, which is the same as vector type for 5643 // integer vectors, or an integer type of identical size and number of 5644 // elements for floating point vectors. 5645 if (lType->isIntegerType()) 5646 return lType; 5647 5648 const VectorType *VTy = lType->getAs<VectorType>(); 5649 unsigned TypeSize = Context.getTypeSize(VTy->getElementType()); 5650 if (TypeSize == Context.getTypeSize(Context.IntTy)) 5651 return Context.getExtVectorType(Context.IntTy, VTy->getNumElements()); 5652 if (TypeSize == Context.getTypeSize(Context.LongTy)) 5653 return Context.getExtVectorType(Context.LongTy, VTy->getNumElements()); 5654 5655 assert(TypeSize == Context.getTypeSize(Context.LongLongTy) && 5656 "Unhandled vector element size in vector compare"); 5657 return Context.getExtVectorType(Context.LongLongTy, VTy->getNumElements()); 5658} 5659 5660inline QualType Sema::CheckBitwiseOperands( 5661 Expr *&lex, Expr *&rex, SourceLocation Loc, bool isCompAssign) { 5662 if (lex->getType()->isVectorType() || rex->getType()->isVectorType()) 5663 return CheckVectorOperands(Loc, lex, rex); 5664 5665 QualType compType = UsualArithmeticConversions(lex, rex, isCompAssign); 5666 5667 if (lex->getType()->isIntegerType() && rex->getType()->isIntegerType()) 5668 return compType; 5669 return InvalidOperands(Loc, lex, rex); 5670} 5671 5672inline QualType Sema::CheckLogicalOperands( // C99 6.5.[13,14] 5673 Expr *&lex, Expr *&rex, SourceLocation Loc) { 5674 if (!Context.getLangOptions().CPlusPlus) { 5675 UsualUnaryConversions(lex); 5676 UsualUnaryConversions(rex); 5677 5678 if (!lex->getType()->isScalarType() || !rex->getType()->isScalarType()) 5679 return InvalidOperands(Loc, lex, rex); 5680 5681 return Context.IntTy; 5682 } 5683 5684 // C++ [expr.log.and]p1 5685 // C++ [expr.log.or]p1 5686 // The operands are both implicitly converted to type bool (clause 4). 5687 StandardConversionSequence LHS; 5688 if (!IsStandardConversion(lex, Context.BoolTy, 5689 /*InOverloadResolution=*/false, LHS)) 5690 return InvalidOperands(Loc, lex, rex); 5691 5692 if (PerformImplicitConversion(lex, Context.BoolTy, LHS, 5693 AA_Passing, /*IgnoreBaseAccess=*/false)) 5694 return InvalidOperands(Loc, lex, rex); 5695 5696 StandardConversionSequence RHS; 5697 if (!IsStandardConversion(rex, Context.BoolTy, 5698 /*InOverloadResolution=*/false, RHS)) 5699 return InvalidOperands(Loc, lex, rex); 5700 5701 if (PerformImplicitConversion(rex, Context.BoolTy, RHS, 5702 AA_Passing, /*IgnoreBaseAccess=*/false)) 5703 return InvalidOperands(Loc, lex, rex); 5704 5705 // C++ [expr.log.and]p2 5706 // C++ [expr.log.or]p2 5707 // The result is a bool. 5708 return Context.BoolTy; 5709} 5710 5711/// IsReadonlyProperty - Verify that otherwise a valid l-value expression 5712/// is a read-only property; return true if so. A readonly property expression 5713/// depends on various declarations and thus must be treated specially. 5714/// 5715static bool IsReadonlyProperty(Expr *E, Sema &S) { 5716 if (E->getStmtClass() == Expr::ObjCPropertyRefExprClass) { 5717 const ObjCPropertyRefExpr* PropExpr = cast<ObjCPropertyRefExpr>(E); 5718 if (ObjCPropertyDecl *PDecl = PropExpr->getProperty()) { 5719 QualType BaseType = PropExpr->getBase()->getType(); 5720 if (const ObjCObjectPointerType *OPT = 5721 BaseType->getAsObjCInterfacePointerType()) 5722 if (ObjCInterfaceDecl *IFace = OPT->getInterfaceDecl()) 5723 if (S.isPropertyReadonly(PDecl, IFace)) 5724 return true; 5725 } 5726 } 5727 return false; 5728} 5729 5730/// CheckForModifiableLvalue - Verify that E is a modifiable lvalue. If not, 5731/// emit an error and return true. If so, return false. 5732static bool CheckForModifiableLvalue(Expr *E, SourceLocation Loc, Sema &S) { 5733 SourceLocation OrigLoc = Loc; 5734 Expr::isModifiableLvalueResult IsLV = E->isModifiableLvalue(S.Context, 5735 &Loc); 5736 if (IsLV == Expr::MLV_Valid && IsReadonlyProperty(E, S)) 5737 IsLV = Expr::MLV_ReadonlyProperty; 5738 if (IsLV == Expr::MLV_Valid) 5739 return false; 5740 5741 unsigned Diag = 0; 5742 bool NeedType = false; 5743 switch (IsLV) { // C99 6.5.16p2 5744 case Expr::MLV_ConstQualified: Diag = diag::err_typecheck_assign_const; break; 5745 case Expr::MLV_ArrayType: 5746 Diag = diag::err_typecheck_array_not_modifiable_lvalue; 5747 NeedType = true; 5748 break; 5749 case Expr::MLV_NotObjectType: 5750 Diag = diag::err_typecheck_non_object_not_modifiable_lvalue; 5751 NeedType = true; 5752 break; 5753 case Expr::MLV_LValueCast: 5754 Diag = diag::err_typecheck_lvalue_casts_not_supported; 5755 break; 5756 case Expr::MLV_Valid: 5757 llvm_unreachable("did not take early return for MLV_Valid"); 5758 case Expr::MLV_InvalidExpression: 5759 case Expr::MLV_MemberFunction: 5760 case Expr::MLV_ClassTemporary: 5761 Diag = diag::err_typecheck_expression_not_modifiable_lvalue; 5762 break; 5763 case Expr::MLV_IncompleteType: 5764 case Expr::MLV_IncompleteVoidType: 5765 return S.RequireCompleteType(Loc, E->getType(), 5766 PDiag(diag::err_typecheck_incomplete_type_not_modifiable_lvalue) 5767 << E->getSourceRange()); 5768 case Expr::MLV_DuplicateVectorComponents: 5769 Diag = diag::err_typecheck_duplicate_vector_components_not_mlvalue; 5770 break; 5771 case Expr::MLV_NotBlockQualified: 5772 Diag = diag::err_block_decl_ref_not_modifiable_lvalue; 5773 break; 5774 case Expr::MLV_ReadonlyProperty: 5775 Diag = diag::error_readonly_property_assignment; 5776 break; 5777 case Expr::MLV_NoSetterProperty: 5778 Diag = diag::error_nosetter_property_assignment; 5779 break; 5780 case Expr::MLV_SubObjCPropertySetting: 5781 Diag = diag::error_no_subobject_property_setting; 5782 break; 5783 case Expr::MLV_SubObjCPropertyGetterSetting: 5784 Diag = diag::error_no_subobject_property_getter_setting; 5785 break; 5786 } 5787 5788 SourceRange Assign; 5789 if (Loc != OrigLoc) 5790 Assign = SourceRange(OrigLoc, OrigLoc); 5791 if (NeedType) 5792 S.Diag(Loc, Diag) << E->getType() << E->getSourceRange() << Assign; 5793 else 5794 S.Diag(Loc, Diag) << E->getSourceRange() << Assign; 5795 return true; 5796} 5797 5798 5799 5800// C99 6.5.16.1 5801QualType Sema::CheckAssignmentOperands(Expr *LHS, Expr *&RHS, 5802 SourceLocation Loc, 5803 QualType CompoundType) { 5804 // Verify that LHS is a modifiable lvalue, and emit error if not. 5805 if (CheckForModifiableLvalue(LHS, Loc, *this)) 5806 return QualType(); 5807 5808 QualType LHSType = LHS->getType(); 5809 QualType RHSType = CompoundType.isNull() ? RHS->getType() : CompoundType; 5810 5811 AssignConvertType ConvTy; 5812 if (CompoundType.isNull()) { 5813 // Simple assignment "x = y". 5814 ConvTy = CheckSingleAssignmentConstraints(LHSType, RHS); 5815 // Special case of NSObject attributes on c-style pointer types. 5816 if (ConvTy == IncompatiblePointer && 5817 ((Context.isObjCNSObjectType(LHSType) && 5818 RHSType->isObjCObjectPointerType()) || 5819 (Context.isObjCNSObjectType(RHSType) && 5820 LHSType->isObjCObjectPointerType()))) 5821 ConvTy = Compatible; 5822 5823 // If the RHS is a unary plus or minus, check to see if they = and + are 5824 // right next to each other. If so, the user may have typo'd "x =+ 4" 5825 // instead of "x += 4". 5826 Expr *RHSCheck = RHS; 5827 if (ImplicitCastExpr *ICE = dyn_cast<ImplicitCastExpr>(RHSCheck)) 5828 RHSCheck = ICE->getSubExpr(); 5829 if (UnaryOperator *UO = dyn_cast<UnaryOperator>(RHSCheck)) { 5830 if ((UO->getOpcode() == UnaryOperator::Plus || 5831 UO->getOpcode() == UnaryOperator::Minus) && 5832 Loc.isFileID() && UO->getOperatorLoc().isFileID() && 5833 // Only if the two operators are exactly adjacent. 5834 Loc.getFileLocWithOffset(1) == UO->getOperatorLoc() && 5835 // And there is a space or other character before the subexpr of the 5836 // unary +/-. We don't want to warn on "x=-1". 5837 Loc.getFileLocWithOffset(2) != UO->getSubExpr()->getLocStart() && 5838 UO->getSubExpr()->getLocStart().isFileID()) { 5839 Diag(Loc, diag::warn_not_compound_assign) 5840 << (UO->getOpcode() == UnaryOperator::Plus ? "+" : "-") 5841 << SourceRange(UO->getOperatorLoc(), UO->getOperatorLoc()); 5842 } 5843 } 5844 } else { 5845 // Compound assignment "x += y" 5846 ConvTy = CheckAssignmentConstraints(LHSType, RHSType); 5847 } 5848 5849 if (DiagnoseAssignmentResult(ConvTy, Loc, LHSType, RHSType, 5850 RHS, AA_Assigning)) 5851 return QualType(); 5852 5853 // C99 6.5.16p3: The type of an assignment expression is the type of the 5854 // left operand unless the left operand has qualified type, in which case 5855 // it is the unqualified version of the type of the left operand. 5856 // C99 6.5.16.1p2: In simple assignment, the value of the right operand 5857 // is converted to the type of the assignment expression (above). 5858 // C++ 5.17p1: the type of the assignment expression is that of its left 5859 // operand. 5860 return LHSType.getUnqualifiedType(); 5861} 5862 5863// C99 6.5.17 5864QualType Sema::CheckCommaOperands(Expr *LHS, Expr *&RHS, SourceLocation Loc) { 5865 // Comma performs lvalue conversion (C99 6.3.2.1), but not unary conversions. 5866 // C++ does not perform this conversion (C++ [expr.comma]p1). 5867 if (!getLangOptions().CPlusPlus) 5868 DefaultFunctionArrayLvalueConversion(RHS); 5869 5870 // FIXME: Check that RHS type is complete in C mode (it's legal for it to be 5871 // incomplete in C++). 5872 5873 return RHS->getType(); 5874} 5875 5876/// CheckIncrementDecrementOperand - unlike most "Check" methods, this routine 5877/// doesn't need to call UsualUnaryConversions or UsualArithmeticConversions. 5878QualType Sema::CheckIncrementDecrementOperand(Expr *Op, SourceLocation OpLoc, 5879 bool isInc) { 5880 if (Op->isTypeDependent()) 5881 return Context.DependentTy; 5882 5883 QualType ResType = Op->getType(); 5884 assert(!ResType.isNull() && "no type for increment/decrement expression"); 5885 5886 if (getLangOptions().CPlusPlus && ResType->isBooleanType()) { 5887 // Decrement of bool is not allowed. 5888 if (!isInc) { 5889 Diag(OpLoc, diag::err_decrement_bool) << Op->getSourceRange(); 5890 return QualType(); 5891 } 5892 // Increment of bool sets it to true, but is deprecated. 5893 Diag(OpLoc, diag::warn_increment_bool) << Op->getSourceRange(); 5894 } else if (ResType->isRealType()) { 5895 // OK! 5896 } else if (ResType->isAnyPointerType()) { 5897 QualType PointeeTy = ResType->getPointeeType(); 5898 5899 // C99 6.5.2.4p2, 6.5.6p2 5900 if (PointeeTy->isVoidType()) { 5901 if (getLangOptions().CPlusPlus) { 5902 Diag(OpLoc, diag::err_typecheck_pointer_arith_void_type) 5903 << Op->getSourceRange(); 5904 return QualType(); 5905 } 5906 5907 // Pointer to void is a GNU extension in C. 5908 Diag(OpLoc, diag::ext_gnu_void_ptr) << Op->getSourceRange(); 5909 } else if (PointeeTy->isFunctionType()) { 5910 if (getLangOptions().CPlusPlus) { 5911 Diag(OpLoc, diag::err_typecheck_pointer_arith_function_type) 5912 << Op->getType() << Op->getSourceRange(); 5913 return QualType(); 5914 } 5915 5916 Diag(OpLoc, diag::ext_gnu_ptr_func_arith) 5917 << ResType << Op->getSourceRange(); 5918 } else if (RequireCompleteType(OpLoc, PointeeTy, 5919 PDiag(diag::err_typecheck_arithmetic_incomplete_type) 5920 << Op->getSourceRange() 5921 << ResType)) 5922 return QualType(); 5923 // Diagnose bad cases where we step over interface counts. 5924 else if (PointeeTy->isObjCInterfaceType() && LangOpts.ObjCNonFragileABI) { 5925 Diag(OpLoc, diag::err_arithmetic_nonfragile_interface) 5926 << PointeeTy << Op->getSourceRange(); 5927 return QualType(); 5928 } 5929 } else if (ResType->isAnyComplexType()) { 5930 // C99 does not support ++/-- on complex types, we allow as an extension. 5931 Diag(OpLoc, diag::ext_integer_increment_complex) 5932 << ResType << Op->getSourceRange(); 5933 } else { 5934 Diag(OpLoc, diag::err_typecheck_illegal_increment_decrement) 5935 << ResType << int(isInc) << Op->getSourceRange(); 5936 return QualType(); 5937 } 5938 // At this point, we know we have a real, complex or pointer type. 5939 // Now make sure the operand is a modifiable lvalue. 5940 if (CheckForModifiableLvalue(Op, OpLoc, *this)) 5941 return QualType(); 5942 return ResType; 5943} 5944 5945/// getPrimaryDecl - Helper function for CheckAddressOfOperand(). 5946/// This routine allows us to typecheck complex/recursive expressions 5947/// where the declaration is needed for type checking. We only need to 5948/// handle cases when the expression references a function designator 5949/// or is an lvalue. Here are some examples: 5950/// - &(x) => x 5951/// - &*****f => f for f a function designator. 5952/// - &s.xx => s 5953/// - &s.zz[1].yy -> s, if zz is an array 5954/// - *(x + 1) -> x, if x is an array 5955/// - &"123"[2] -> 0 5956/// - & __real__ x -> x 5957static NamedDecl *getPrimaryDecl(Expr *E) { 5958 switch (E->getStmtClass()) { 5959 case Stmt::DeclRefExprClass: 5960 return cast<DeclRefExpr>(E)->getDecl(); 5961 case Stmt::MemberExprClass: 5962 // If this is an arrow operator, the address is an offset from 5963 // the base's value, so the object the base refers to is 5964 // irrelevant. 5965 if (cast<MemberExpr>(E)->isArrow()) 5966 return 0; 5967 // Otherwise, the expression refers to a part of the base 5968 return getPrimaryDecl(cast<MemberExpr>(E)->getBase()); 5969 case Stmt::ArraySubscriptExprClass: { 5970 // FIXME: This code shouldn't be necessary! We should catch the implicit 5971 // promotion of register arrays earlier. 5972 Expr* Base = cast<ArraySubscriptExpr>(E)->getBase(); 5973 if (ImplicitCastExpr* ICE = dyn_cast<ImplicitCastExpr>(Base)) { 5974 if (ICE->getSubExpr()->getType()->isArrayType()) 5975 return getPrimaryDecl(ICE->getSubExpr()); 5976 } 5977 return 0; 5978 } 5979 case Stmt::UnaryOperatorClass: { 5980 UnaryOperator *UO = cast<UnaryOperator>(E); 5981 5982 switch(UO->getOpcode()) { 5983 case UnaryOperator::Real: 5984 case UnaryOperator::Imag: 5985 case UnaryOperator::Extension: 5986 return getPrimaryDecl(UO->getSubExpr()); 5987 default: 5988 return 0; 5989 } 5990 } 5991 case Stmt::ParenExprClass: 5992 return getPrimaryDecl(cast<ParenExpr>(E)->getSubExpr()); 5993 case Stmt::ImplicitCastExprClass: 5994 // If the result of an implicit cast is an l-value, we care about 5995 // the sub-expression; otherwise, the result here doesn't matter. 5996 return getPrimaryDecl(cast<ImplicitCastExpr>(E)->getSubExpr()); 5997 default: 5998 return 0; 5999 } 6000} 6001 6002/// CheckAddressOfOperand - The operand of & must be either a function 6003/// designator or an lvalue designating an object. If it is an lvalue, the 6004/// object cannot be declared with storage class register or be a bit field. 6005/// Note: The usual conversions are *not* applied to the operand of the & 6006/// operator (C99 6.3.2.1p[2-4]), and its result is never an lvalue. 6007/// In C++, the operand might be an overloaded function name, in which case 6008/// we allow the '&' but retain the overloaded-function type. 6009QualType Sema::CheckAddressOfOperand(Expr *op, SourceLocation OpLoc) { 6010 // Make sure to ignore parentheses in subsequent checks 6011 op = op->IgnoreParens(); 6012 6013 if (op->isTypeDependent()) 6014 return Context.DependentTy; 6015 6016 if (getLangOptions().C99) { 6017 // Implement C99-only parts of addressof rules. 6018 if (UnaryOperator* uOp = dyn_cast<UnaryOperator>(op)) { 6019 if (uOp->getOpcode() == UnaryOperator::Deref) 6020 // Per C99 6.5.3.2, the address of a deref always returns a valid result 6021 // (assuming the deref expression is valid). 6022 return uOp->getSubExpr()->getType(); 6023 } 6024 // Technically, there should be a check for array subscript 6025 // expressions here, but the result of one is always an lvalue anyway. 6026 } 6027 NamedDecl *dcl = getPrimaryDecl(op); 6028 Expr::isLvalueResult lval = op->isLvalue(Context); 6029 6030 MemberExpr *ME = dyn_cast<MemberExpr>(op); 6031 if (lval == Expr::LV_MemberFunction && ME && 6032 isa<CXXMethodDecl>(ME->getMemberDecl())) { 6033 ValueDecl *dcl = cast<MemberExpr>(op)->getMemberDecl(); 6034 // &f where f is a member of the current object, or &o.f, or &p->f 6035 // All these are not allowed, and we need to catch them before the dcl 6036 // branch of the if, below. 6037 Diag(OpLoc, diag::err_unqualified_pointer_member_function) 6038 << dcl; 6039 // FIXME: Improve this diagnostic and provide a fixit. 6040 6041 // Now recover by acting as if the function had been accessed qualified. 6042 return Context.getMemberPointerType(op->getType(), 6043 Context.getTypeDeclType(cast<RecordDecl>(dcl->getDeclContext())) 6044 .getTypePtr()); 6045 } else if (lval == Expr::LV_ClassTemporary) { 6046 Diag(OpLoc, isSFINAEContext()? diag::err_typecheck_addrof_class_temporary 6047 : diag::ext_typecheck_addrof_class_temporary) 6048 << op->getType() << op->getSourceRange(); 6049 if (isSFINAEContext()) 6050 return QualType(); 6051 } else if (lval != Expr::LV_Valid && lval != Expr::LV_IncompleteVoidType) { 6052 // C99 6.5.3.2p1 6053 // The operand must be either an l-value or a function designator 6054 if (!op->getType()->isFunctionType()) { 6055 // FIXME: emit more specific diag... 6056 Diag(OpLoc, diag::err_typecheck_invalid_lvalue_addrof) 6057 << op->getSourceRange(); 6058 return QualType(); 6059 } 6060 } else if (op->getBitField()) { // C99 6.5.3.2p1 6061 // The operand cannot be a bit-field 6062 Diag(OpLoc, diag::err_typecheck_address_of) 6063 << "bit-field" << op->getSourceRange(); 6064 return QualType(); 6065 } else if (op->refersToVectorElement()) { 6066 // The operand cannot be an element of a vector 6067 Diag(OpLoc, diag::err_typecheck_address_of) 6068 << "vector element" << op->getSourceRange(); 6069 return QualType(); 6070 } else if (isa<ObjCPropertyRefExpr>(op)) { 6071 // cannot take address of a property expression. 6072 Diag(OpLoc, diag::err_typecheck_address_of) 6073 << "property expression" << op->getSourceRange(); 6074 return QualType(); 6075 } else if (ConditionalOperator *CO = dyn_cast<ConditionalOperator>(op)) { 6076 // FIXME: Can LHS ever be null here? 6077 if (!CheckAddressOfOperand(CO->getTrueExpr(), OpLoc).isNull()) 6078 return CheckAddressOfOperand(CO->getFalseExpr(), OpLoc); 6079 } else if (isa<UnresolvedLookupExpr>(op)) { 6080 return Context.OverloadTy; 6081 } else if (dcl) { // C99 6.5.3.2p1 6082 // We have an lvalue with a decl. Make sure the decl is not declared 6083 // with the register storage-class specifier. 6084 if (const VarDecl *vd = dyn_cast<VarDecl>(dcl)) { 6085 if (vd->getStorageClass() == VarDecl::Register) { 6086 Diag(OpLoc, diag::err_typecheck_address_of) 6087 << "register variable" << op->getSourceRange(); 6088 return QualType(); 6089 } 6090 } else if (isa<FunctionTemplateDecl>(dcl)) { 6091 return Context.OverloadTy; 6092 } else if (FieldDecl *FD = dyn_cast<FieldDecl>(dcl)) { 6093 // Okay: we can take the address of a field. 6094 // Could be a pointer to member, though, if there is an explicit 6095 // scope qualifier for the class. 6096 if (isa<DeclRefExpr>(op) && cast<DeclRefExpr>(op)->getQualifier()) { 6097 DeclContext *Ctx = dcl->getDeclContext(); 6098 if (Ctx && Ctx->isRecord()) { 6099 if (FD->getType()->isReferenceType()) { 6100 Diag(OpLoc, 6101 diag::err_cannot_form_pointer_to_member_of_reference_type) 6102 << FD->getDeclName() << FD->getType(); 6103 return QualType(); 6104 } 6105 6106 return Context.getMemberPointerType(op->getType(), 6107 Context.getTypeDeclType(cast<RecordDecl>(Ctx)).getTypePtr()); 6108 } 6109 } 6110 } else if (CXXMethodDecl *MD = dyn_cast<CXXMethodDecl>(dcl)) { 6111 // Okay: we can take the address of a function. 6112 // As above. 6113 if (isa<DeclRefExpr>(op) && cast<DeclRefExpr>(op)->getQualifier() && 6114 MD->isInstance()) 6115 return Context.getMemberPointerType(op->getType(), 6116 Context.getTypeDeclType(MD->getParent()).getTypePtr()); 6117 } else if (!isa<FunctionDecl>(dcl)) 6118 assert(0 && "Unknown/unexpected decl type"); 6119 } 6120 6121 if (lval == Expr::LV_IncompleteVoidType) { 6122 // Taking the address of a void variable is technically illegal, but we 6123 // allow it in cases which are otherwise valid. 6124 // Example: "extern void x; void* y = &x;". 6125 Diag(OpLoc, diag::ext_typecheck_addrof_void) << op->getSourceRange(); 6126 } 6127 6128 // If the operand has type "type", the result has type "pointer to type". 6129 return Context.getPointerType(op->getType()); 6130} 6131 6132QualType Sema::CheckIndirectionOperand(Expr *Op, SourceLocation OpLoc) { 6133 if (Op->isTypeDependent()) 6134 return Context.DependentTy; 6135 6136 UsualUnaryConversions(Op); 6137 QualType Ty = Op->getType(); 6138 6139 // Note that per both C89 and C99, this is always legal, even if ptype is an 6140 // incomplete type or void. It would be possible to warn about dereferencing 6141 // a void pointer, but it's completely well-defined, and such a warning is 6142 // unlikely to catch any mistakes. 6143 if (const PointerType *PT = Ty->getAs<PointerType>()) 6144 return PT->getPointeeType(); 6145 6146 if (const ObjCObjectPointerType *OPT = Ty->getAs<ObjCObjectPointerType>()) 6147 return OPT->getPointeeType(); 6148 6149 Diag(OpLoc, diag::err_typecheck_indirection_requires_pointer) 6150 << Ty << Op->getSourceRange(); 6151 return QualType(); 6152} 6153 6154static inline BinaryOperator::Opcode ConvertTokenKindToBinaryOpcode( 6155 tok::TokenKind Kind) { 6156 BinaryOperator::Opcode Opc; 6157 switch (Kind) { 6158 default: assert(0 && "Unknown binop!"); 6159 case tok::periodstar: Opc = BinaryOperator::PtrMemD; break; 6160 case tok::arrowstar: Opc = BinaryOperator::PtrMemI; break; 6161 case tok::star: Opc = BinaryOperator::Mul; break; 6162 case tok::slash: Opc = BinaryOperator::Div; break; 6163 case tok::percent: Opc = BinaryOperator::Rem; break; 6164 case tok::plus: Opc = BinaryOperator::Add; break; 6165 case tok::minus: Opc = BinaryOperator::Sub; break; 6166 case tok::lessless: Opc = BinaryOperator::Shl; break; 6167 case tok::greatergreater: Opc = BinaryOperator::Shr; break; 6168 case tok::lessequal: Opc = BinaryOperator::LE; break; 6169 case tok::less: Opc = BinaryOperator::LT; break; 6170 case tok::greaterequal: Opc = BinaryOperator::GE; break; 6171 case tok::greater: Opc = BinaryOperator::GT; break; 6172 case tok::exclaimequal: Opc = BinaryOperator::NE; break; 6173 case tok::equalequal: Opc = BinaryOperator::EQ; break; 6174 case tok::amp: Opc = BinaryOperator::And; break; 6175 case tok::caret: Opc = BinaryOperator::Xor; break; 6176 case tok::pipe: Opc = BinaryOperator::Or; break; 6177 case tok::ampamp: Opc = BinaryOperator::LAnd; break; 6178 case tok::pipepipe: Opc = BinaryOperator::LOr; break; 6179 case tok::equal: Opc = BinaryOperator::Assign; break; 6180 case tok::starequal: Opc = BinaryOperator::MulAssign; break; 6181 case tok::slashequal: Opc = BinaryOperator::DivAssign; break; 6182 case tok::percentequal: Opc = BinaryOperator::RemAssign; break; 6183 case tok::plusequal: Opc = BinaryOperator::AddAssign; break; 6184 case tok::minusequal: Opc = BinaryOperator::SubAssign; break; 6185 case tok::lesslessequal: Opc = BinaryOperator::ShlAssign; break; 6186 case tok::greatergreaterequal: Opc = BinaryOperator::ShrAssign; break; 6187 case tok::ampequal: Opc = BinaryOperator::AndAssign; break; 6188 case tok::caretequal: Opc = BinaryOperator::XorAssign; break; 6189 case tok::pipeequal: Opc = BinaryOperator::OrAssign; break; 6190 case tok::comma: Opc = BinaryOperator::Comma; break; 6191 } 6192 return Opc; 6193} 6194 6195static inline UnaryOperator::Opcode ConvertTokenKindToUnaryOpcode( 6196 tok::TokenKind Kind) { 6197 UnaryOperator::Opcode Opc; 6198 switch (Kind) { 6199 default: assert(0 && "Unknown unary op!"); 6200 case tok::plusplus: Opc = UnaryOperator::PreInc; break; 6201 case tok::minusminus: Opc = UnaryOperator::PreDec; break; 6202 case tok::amp: Opc = UnaryOperator::AddrOf; break; 6203 case tok::star: Opc = UnaryOperator::Deref; break; 6204 case tok::plus: Opc = UnaryOperator::Plus; break; 6205 case tok::minus: Opc = UnaryOperator::Minus; break; 6206 case tok::tilde: Opc = UnaryOperator::Not; break; 6207 case tok::exclaim: Opc = UnaryOperator::LNot; break; 6208 case tok::kw___real: Opc = UnaryOperator::Real; break; 6209 case tok::kw___imag: Opc = UnaryOperator::Imag; break; 6210 case tok::kw___extension__: Opc = UnaryOperator::Extension; break; 6211 } 6212 return Opc; 6213} 6214 6215/// CreateBuiltinBinOp - Creates a new built-in binary operation with 6216/// operator @p Opc at location @c TokLoc. This routine only supports 6217/// built-in operations; ActOnBinOp handles overloaded operators. 6218Action::OwningExprResult Sema::CreateBuiltinBinOp(SourceLocation OpLoc, 6219 unsigned Op, 6220 Expr *lhs, Expr *rhs) { 6221 QualType ResultTy; // Result type of the binary operator. 6222 BinaryOperator::Opcode Opc = (BinaryOperator::Opcode)Op; 6223 // The following two variables are used for compound assignment operators 6224 QualType CompLHSTy; // Type of LHS after promotions for computation 6225 QualType CompResultTy; // Type of computation result 6226 6227 switch (Opc) { 6228 case BinaryOperator::Assign: 6229 ResultTy = CheckAssignmentOperands(lhs, rhs, OpLoc, QualType()); 6230 break; 6231 case BinaryOperator::PtrMemD: 6232 case BinaryOperator::PtrMemI: 6233 ResultTy = CheckPointerToMemberOperands(lhs, rhs, OpLoc, 6234 Opc == BinaryOperator::PtrMemI); 6235 break; 6236 case BinaryOperator::Mul: 6237 case BinaryOperator::Div: 6238 ResultTy = CheckMultiplyDivideOperands(lhs, rhs, OpLoc, false, 6239 Opc == BinaryOperator::Div); 6240 break; 6241 case BinaryOperator::Rem: 6242 ResultTy = CheckRemainderOperands(lhs, rhs, OpLoc); 6243 break; 6244 case BinaryOperator::Add: 6245 ResultTy = CheckAdditionOperands(lhs, rhs, OpLoc); 6246 break; 6247 case BinaryOperator::Sub: 6248 ResultTy = CheckSubtractionOperands(lhs, rhs, OpLoc); 6249 break; 6250 case BinaryOperator::Shl: 6251 case BinaryOperator::Shr: 6252 ResultTy = CheckShiftOperands(lhs, rhs, OpLoc); 6253 break; 6254 case BinaryOperator::LE: 6255 case BinaryOperator::LT: 6256 case BinaryOperator::GE: 6257 case BinaryOperator::GT: 6258 ResultTy = CheckCompareOperands(lhs, rhs, OpLoc, Opc, true); 6259 break; 6260 case BinaryOperator::EQ: 6261 case BinaryOperator::NE: 6262 ResultTy = CheckCompareOperands(lhs, rhs, OpLoc, Opc, false); 6263 break; 6264 case BinaryOperator::And: 6265 case BinaryOperator::Xor: 6266 case BinaryOperator::Or: 6267 ResultTy = CheckBitwiseOperands(lhs, rhs, OpLoc); 6268 break; 6269 case BinaryOperator::LAnd: 6270 case BinaryOperator::LOr: 6271 ResultTy = CheckLogicalOperands(lhs, rhs, OpLoc); 6272 break; 6273 case BinaryOperator::MulAssign: 6274 case BinaryOperator::DivAssign: 6275 CompResultTy = CheckMultiplyDivideOperands(lhs, rhs, OpLoc, true, 6276 Opc == BinaryOperator::DivAssign); 6277 CompLHSTy = CompResultTy; 6278 if (!CompResultTy.isNull()) 6279 ResultTy = CheckAssignmentOperands(lhs, rhs, OpLoc, CompResultTy); 6280 break; 6281 case BinaryOperator::RemAssign: 6282 CompResultTy = CheckRemainderOperands(lhs, rhs, OpLoc, true); 6283 CompLHSTy = CompResultTy; 6284 if (!CompResultTy.isNull()) 6285 ResultTy = CheckAssignmentOperands(lhs, rhs, OpLoc, CompResultTy); 6286 break; 6287 case BinaryOperator::AddAssign: 6288 CompResultTy = CheckAdditionOperands(lhs, rhs, OpLoc, &CompLHSTy); 6289 if (!CompResultTy.isNull()) 6290 ResultTy = CheckAssignmentOperands(lhs, rhs, OpLoc, CompResultTy); 6291 break; 6292 case BinaryOperator::SubAssign: 6293 CompResultTy = CheckSubtractionOperands(lhs, rhs, OpLoc, &CompLHSTy); 6294 if (!CompResultTy.isNull()) 6295 ResultTy = CheckAssignmentOperands(lhs, rhs, OpLoc, CompResultTy); 6296 break; 6297 case BinaryOperator::ShlAssign: 6298 case BinaryOperator::ShrAssign: 6299 CompResultTy = CheckShiftOperands(lhs, rhs, OpLoc, true); 6300 CompLHSTy = CompResultTy; 6301 if (!CompResultTy.isNull()) 6302 ResultTy = CheckAssignmentOperands(lhs, rhs, OpLoc, CompResultTy); 6303 break; 6304 case BinaryOperator::AndAssign: 6305 case BinaryOperator::XorAssign: 6306 case BinaryOperator::OrAssign: 6307 CompResultTy = CheckBitwiseOperands(lhs, rhs, OpLoc, true); 6308 CompLHSTy = CompResultTy; 6309 if (!CompResultTy.isNull()) 6310 ResultTy = CheckAssignmentOperands(lhs, rhs, OpLoc, CompResultTy); 6311 break; 6312 case BinaryOperator::Comma: 6313 ResultTy = CheckCommaOperands(lhs, rhs, OpLoc); 6314 break; 6315 } 6316 if (ResultTy.isNull()) 6317 return ExprError(); 6318 if (CompResultTy.isNull()) 6319 return Owned(new (Context) BinaryOperator(lhs, rhs, Opc, ResultTy, OpLoc)); 6320 else 6321 return Owned(new (Context) CompoundAssignOperator(lhs, rhs, Opc, ResultTy, 6322 CompLHSTy, CompResultTy, 6323 OpLoc)); 6324} 6325 6326/// SuggestParentheses - Emit a diagnostic together with a fixit hint that wraps 6327/// ParenRange in parentheses. 6328static void SuggestParentheses(Sema &Self, SourceLocation Loc, 6329 const PartialDiagnostic &PD, 6330 SourceRange ParenRange, 6331 const PartialDiagnostic &SecondPD = PartialDiagnostic(0), 6332 SourceRange SecondParenRange = SourceRange()) { 6333 SourceLocation EndLoc = Self.PP.getLocForEndOfToken(ParenRange.getEnd()); 6334 if (!ParenRange.getEnd().isFileID() || EndLoc.isInvalid()) { 6335 // We can't display the parentheses, so just dig the 6336 // warning/error and return. 6337 Self.Diag(Loc, PD); 6338 return; 6339 } 6340 6341 Self.Diag(Loc, PD) 6342 << CodeModificationHint::CreateInsertion(ParenRange.getBegin(), "(") 6343 << CodeModificationHint::CreateInsertion(EndLoc, ")"); 6344 6345 if (!SecondPD.getDiagID()) 6346 return; 6347 6348 EndLoc = Self.PP.getLocForEndOfToken(SecondParenRange.getEnd()); 6349 if (!SecondParenRange.getEnd().isFileID() || EndLoc.isInvalid()) { 6350 // We can't display the parentheses, so just dig the 6351 // warning/error and return. 6352 Self.Diag(Loc, SecondPD); 6353 return; 6354 } 6355 6356 Self.Diag(Loc, SecondPD) 6357 << CodeModificationHint::CreateInsertion(SecondParenRange.getBegin(), "(") 6358 << CodeModificationHint::CreateInsertion(EndLoc, ")"); 6359} 6360 6361/// DiagnoseBitwisePrecedence - Emit a warning when bitwise and comparison 6362/// operators are mixed in a way that suggests that the programmer forgot that 6363/// comparison operators have higher precedence. The most typical example of 6364/// such code is "flags & 0x0020 != 0", which is equivalent to "flags & 1". 6365static void DiagnoseBitwisePrecedence(Sema &Self, BinaryOperator::Opcode Opc, 6366 SourceLocation OpLoc,Expr *lhs,Expr *rhs){ 6367 typedef BinaryOperator BinOp; 6368 BinOp::Opcode lhsopc = static_cast<BinOp::Opcode>(-1), 6369 rhsopc = static_cast<BinOp::Opcode>(-1); 6370 if (BinOp *BO = dyn_cast<BinOp>(lhs)) 6371 lhsopc = BO->getOpcode(); 6372 if (BinOp *BO = dyn_cast<BinOp>(rhs)) 6373 rhsopc = BO->getOpcode(); 6374 6375 // Subs are not binary operators. 6376 if (lhsopc == -1 && rhsopc == -1) 6377 return; 6378 6379 // Bitwise operations are sometimes used as eager logical ops. 6380 // Don't diagnose this. 6381 if ((BinOp::isComparisonOp(lhsopc) || BinOp::isBitwiseOp(lhsopc)) && 6382 (BinOp::isComparisonOp(rhsopc) || BinOp::isBitwiseOp(rhsopc))) 6383 return; 6384 6385 if (BinOp::isComparisonOp(lhsopc)) 6386 SuggestParentheses(Self, OpLoc, 6387 PDiag(diag::warn_precedence_bitwise_rel) 6388 << SourceRange(lhs->getLocStart(), OpLoc) 6389 << BinOp::getOpcodeStr(Opc) << BinOp::getOpcodeStr(lhsopc), 6390 lhs->getSourceRange(), 6391 PDiag(diag::note_precedence_bitwise_first) 6392 << BinOp::getOpcodeStr(Opc), 6393 SourceRange(cast<BinOp>(lhs)->getRHS()->getLocStart(), rhs->getLocEnd())); 6394 else if (BinOp::isComparisonOp(rhsopc)) 6395 SuggestParentheses(Self, OpLoc, 6396 PDiag(diag::warn_precedence_bitwise_rel) 6397 << SourceRange(OpLoc, rhs->getLocEnd()) 6398 << BinOp::getOpcodeStr(Opc) << BinOp::getOpcodeStr(rhsopc), 6399 rhs->getSourceRange(), 6400 PDiag(diag::note_precedence_bitwise_first) 6401 << BinOp::getOpcodeStr(Opc), 6402 SourceRange(lhs->getLocEnd(), cast<BinOp>(rhs)->getLHS()->getLocStart())); 6403} 6404 6405/// DiagnoseBinOpPrecedence - Emit warnings for expressions with tricky 6406/// precedence. This currently diagnoses only "arg1 'bitwise' arg2 'eq' arg3". 6407/// But it could also warn about arg1 && arg2 || arg3, as GCC 4.3+ does. 6408static void DiagnoseBinOpPrecedence(Sema &Self, BinaryOperator::Opcode Opc, 6409 SourceLocation OpLoc, Expr *lhs, Expr *rhs){ 6410 if (BinaryOperator::isBitwiseOp(Opc)) 6411 DiagnoseBitwisePrecedence(Self, Opc, OpLoc, lhs, rhs); 6412} 6413 6414// Binary Operators. 'Tok' is the token for the operator. 6415Action::OwningExprResult Sema::ActOnBinOp(Scope *S, SourceLocation TokLoc, 6416 tok::TokenKind Kind, 6417 ExprArg LHS, ExprArg RHS) { 6418 BinaryOperator::Opcode Opc = ConvertTokenKindToBinaryOpcode(Kind); 6419 Expr *lhs = LHS.takeAs<Expr>(), *rhs = RHS.takeAs<Expr>(); 6420 6421 assert((lhs != 0) && "ActOnBinOp(): missing left expression"); 6422 assert((rhs != 0) && "ActOnBinOp(): missing right expression"); 6423 6424 // Emit warnings for tricky precedence issues, e.g. "bitfield & 0x4 == 0" 6425 DiagnoseBinOpPrecedence(*this, Opc, TokLoc, lhs, rhs); 6426 6427 return BuildBinOp(S, TokLoc, Opc, lhs, rhs); 6428} 6429 6430Action::OwningExprResult Sema::BuildBinOp(Scope *S, SourceLocation OpLoc, 6431 BinaryOperator::Opcode Opc, 6432 Expr *lhs, Expr *rhs) { 6433 if (getLangOptions().CPlusPlus && 6434 (lhs->getType()->isOverloadableType() || 6435 rhs->getType()->isOverloadableType())) { 6436 // Find all of the overloaded operators visible from this 6437 // point. We perform both an operator-name lookup from the local 6438 // scope and an argument-dependent lookup based on the types of 6439 // the arguments. 6440 UnresolvedSet<16> Functions; 6441 OverloadedOperatorKind OverOp = BinaryOperator::getOverloadedOperator(Opc); 6442 if (S && OverOp != OO_None) 6443 LookupOverloadedOperatorName(OverOp, S, lhs->getType(), rhs->getType(), 6444 Functions); 6445 6446 // Build the (potentially-overloaded, potentially-dependent) 6447 // binary operation. 6448 return CreateOverloadedBinOp(OpLoc, Opc, Functions, lhs, rhs); 6449 } 6450 6451 // Build a built-in binary operation. 6452 return CreateBuiltinBinOp(OpLoc, Opc, lhs, rhs); 6453} 6454 6455Action::OwningExprResult Sema::CreateBuiltinUnaryOp(SourceLocation OpLoc, 6456 unsigned OpcIn, 6457 ExprArg InputArg) { 6458 UnaryOperator::Opcode Opc = static_cast<UnaryOperator::Opcode>(OpcIn); 6459 6460 // FIXME: Input is modified below, but InputArg is not updated appropriately. 6461 Expr *Input = (Expr *)InputArg.get(); 6462 QualType resultType; 6463 switch (Opc) { 6464 case UnaryOperator::OffsetOf: 6465 assert(false && "Invalid unary operator"); 6466 break; 6467 6468 case UnaryOperator::PreInc: 6469 case UnaryOperator::PreDec: 6470 case UnaryOperator::PostInc: 6471 case UnaryOperator::PostDec: 6472 resultType = CheckIncrementDecrementOperand(Input, OpLoc, 6473 Opc == UnaryOperator::PreInc || 6474 Opc == UnaryOperator::PostInc); 6475 break; 6476 case UnaryOperator::AddrOf: 6477 resultType = CheckAddressOfOperand(Input, OpLoc); 6478 break; 6479 case UnaryOperator::Deref: 6480 DefaultFunctionArrayLvalueConversion(Input); 6481 resultType = CheckIndirectionOperand(Input, OpLoc); 6482 break; 6483 case UnaryOperator::Plus: 6484 case UnaryOperator::Minus: 6485 UsualUnaryConversions(Input); 6486 resultType = Input->getType(); 6487 if (resultType->isDependentType()) 6488 break; 6489 if (resultType->isArithmeticType()) // C99 6.5.3.3p1 6490 break; 6491 else if (getLangOptions().CPlusPlus && // C++ [expr.unary.op]p6-7 6492 resultType->isEnumeralType()) 6493 break; 6494 else if (getLangOptions().CPlusPlus && // C++ [expr.unary.op]p6 6495 Opc == UnaryOperator::Plus && 6496 resultType->isPointerType()) 6497 break; 6498 6499 return ExprError(Diag(OpLoc, diag::err_typecheck_unary_expr) 6500 << resultType << Input->getSourceRange()); 6501 case UnaryOperator::Not: // bitwise complement 6502 UsualUnaryConversions(Input); 6503 resultType = Input->getType(); 6504 if (resultType->isDependentType()) 6505 break; 6506 // C99 6.5.3.3p1. We allow complex int and float as a GCC extension. 6507 if (resultType->isComplexType() || resultType->isComplexIntegerType()) 6508 // C99 does not support '~' for complex conjugation. 6509 Diag(OpLoc, diag::ext_integer_complement_complex) 6510 << resultType << Input->getSourceRange(); 6511 else if (!resultType->isIntegerType()) 6512 return ExprError(Diag(OpLoc, diag::err_typecheck_unary_expr) 6513 << resultType << Input->getSourceRange()); 6514 break; 6515 case UnaryOperator::LNot: // logical negation 6516 // Unlike +/-/~, integer promotions aren't done here (C99 6.5.3.3p5). 6517 DefaultFunctionArrayLvalueConversion(Input); 6518 resultType = Input->getType(); 6519 if (resultType->isDependentType()) 6520 break; 6521 if (!resultType->isScalarType()) // C99 6.5.3.3p1 6522 return ExprError(Diag(OpLoc, diag::err_typecheck_unary_expr) 6523 << resultType << Input->getSourceRange()); 6524 // LNot always has type int. C99 6.5.3.3p5. 6525 // In C++, it's bool. C++ 5.3.1p8 6526 resultType = getLangOptions().CPlusPlus ? Context.BoolTy : Context.IntTy; 6527 break; 6528 case UnaryOperator::Real: 6529 case UnaryOperator::Imag: 6530 resultType = CheckRealImagOperand(Input, OpLoc, Opc == UnaryOperator::Real); 6531 break; 6532 case UnaryOperator::Extension: 6533 resultType = Input->getType(); 6534 break; 6535 } 6536 if (resultType.isNull()) 6537 return ExprError(); 6538 6539 InputArg.release(); 6540 return Owned(new (Context) UnaryOperator(Input, Opc, resultType, OpLoc)); 6541} 6542 6543Action::OwningExprResult Sema::BuildUnaryOp(Scope *S, SourceLocation OpLoc, 6544 UnaryOperator::Opcode Opc, 6545 ExprArg input) { 6546 Expr *Input = (Expr*)input.get(); 6547 if (getLangOptions().CPlusPlus && Input->getType()->isOverloadableType() && 6548 Opc != UnaryOperator::Extension) { 6549 // Find all of the overloaded operators visible from this 6550 // point. We perform both an operator-name lookup from the local 6551 // scope and an argument-dependent lookup based on the types of 6552 // the arguments. 6553 UnresolvedSet<16> Functions; 6554 OverloadedOperatorKind OverOp = UnaryOperator::getOverloadedOperator(Opc); 6555 if (S && OverOp != OO_None) 6556 LookupOverloadedOperatorName(OverOp, S, Input->getType(), QualType(), 6557 Functions); 6558 6559 return CreateOverloadedUnaryOp(OpLoc, Opc, Functions, move(input)); 6560 } 6561 6562 return CreateBuiltinUnaryOp(OpLoc, Opc, move(input)); 6563} 6564 6565// Unary Operators. 'Tok' is the token for the operator. 6566Action::OwningExprResult Sema::ActOnUnaryOp(Scope *S, SourceLocation OpLoc, 6567 tok::TokenKind Op, ExprArg input) { 6568 return BuildUnaryOp(S, OpLoc, ConvertTokenKindToUnaryOpcode(Op), move(input)); 6569} 6570 6571/// ActOnAddrLabel - Parse the GNU address of label extension: "&&foo". 6572Sema::OwningExprResult Sema::ActOnAddrLabel(SourceLocation OpLoc, 6573 SourceLocation LabLoc, 6574 IdentifierInfo *LabelII) { 6575 // Look up the record for this label identifier. 6576 LabelStmt *&LabelDecl = getLabelMap()[LabelII]; 6577 6578 // If we haven't seen this label yet, create a forward reference. It 6579 // will be validated and/or cleaned up in ActOnFinishFunctionBody. 6580 if (LabelDecl == 0) 6581 LabelDecl = new (Context) LabelStmt(LabLoc, LabelII, 0); 6582 6583 // Create the AST node. The address of a label always has type 'void*'. 6584 return Owned(new (Context) AddrLabelExpr(OpLoc, LabLoc, LabelDecl, 6585 Context.getPointerType(Context.VoidTy))); 6586} 6587 6588Sema::OwningExprResult 6589Sema::ActOnStmtExpr(SourceLocation LPLoc, StmtArg substmt, 6590 SourceLocation RPLoc) { // "({..})" 6591 Stmt *SubStmt = static_cast<Stmt*>(substmt.get()); 6592 assert(SubStmt && isa<CompoundStmt>(SubStmt) && "Invalid action invocation!"); 6593 CompoundStmt *Compound = cast<CompoundStmt>(SubStmt); 6594 6595 bool isFileScope 6596 = (getCurFunctionOrMethodDecl() == 0) && (getCurBlock() == 0); 6597 if (isFileScope) 6598 return ExprError(Diag(LPLoc, diag::err_stmtexpr_file_scope)); 6599 6600 // FIXME: there are a variety of strange constraints to enforce here, for 6601 // example, it is not possible to goto into a stmt expression apparently. 6602 // More semantic analysis is needed. 6603 6604 // If there are sub stmts in the compound stmt, take the type of the last one 6605 // as the type of the stmtexpr. 6606 QualType Ty = Context.VoidTy; 6607 6608 if (!Compound->body_empty()) { 6609 Stmt *LastStmt = Compound->body_back(); 6610 // If LastStmt is a label, skip down through into the body. 6611 while (LabelStmt *Label = dyn_cast<LabelStmt>(LastStmt)) 6612 LastStmt = Label->getSubStmt(); 6613 6614 if (Expr *LastExpr = dyn_cast<Expr>(LastStmt)) 6615 Ty = LastExpr->getType(); 6616 } 6617 6618 // FIXME: Check that expression type is complete/non-abstract; statement 6619 // expressions are not lvalues. 6620 6621 substmt.release(); 6622 return Owned(new (Context) StmtExpr(Compound, Ty, LPLoc, RPLoc)); 6623} 6624 6625Sema::OwningExprResult Sema::ActOnBuiltinOffsetOf(Scope *S, 6626 SourceLocation BuiltinLoc, 6627 SourceLocation TypeLoc, 6628 TypeTy *argty, 6629 OffsetOfComponent *CompPtr, 6630 unsigned NumComponents, 6631 SourceLocation RPLoc) { 6632 // FIXME: This function leaks all expressions in the offset components on 6633 // error. 6634 // FIXME: Preserve type source info. 6635 QualType ArgTy = GetTypeFromParser(argty); 6636 assert(!ArgTy.isNull() && "Missing type argument!"); 6637 6638 bool Dependent = ArgTy->isDependentType(); 6639 6640 // We must have at least one component that refers to the type, and the first 6641 // one is known to be a field designator. Verify that the ArgTy represents 6642 // a struct/union/class. 6643 if (!Dependent && !ArgTy->isRecordType()) 6644 return ExprError(Diag(TypeLoc, diag::err_offsetof_record_type) << ArgTy); 6645 6646 // FIXME: Type must be complete per C99 7.17p3 because a declaring a variable 6647 // with an incomplete type would be illegal. 6648 6649 // Otherwise, create a null pointer as the base, and iteratively process 6650 // the offsetof designators. 6651 QualType ArgTyPtr = Context.getPointerType(ArgTy); 6652 Expr* Res = new (Context) ImplicitValueInitExpr(ArgTyPtr); 6653 Res = new (Context) UnaryOperator(Res, UnaryOperator::Deref, 6654 ArgTy, SourceLocation()); 6655 6656 // offsetof with non-identifier designators (e.g. "offsetof(x, a.b[c])") are a 6657 // GCC extension, diagnose them. 6658 // FIXME: This diagnostic isn't actually visible because the location is in 6659 // a system header! 6660 if (NumComponents != 1) 6661 Diag(BuiltinLoc, diag::ext_offsetof_extended_field_designator) 6662 << SourceRange(CompPtr[1].LocStart, CompPtr[NumComponents-1].LocEnd); 6663 6664 if (!Dependent) { 6665 bool DidWarnAboutNonPOD = false; 6666 6667 if (RequireCompleteType(TypeLoc, Res->getType(), 6668 diag::err_offsetof_incomplete_type)) 6669 return ExprError(); 6670 6671 // FIXME: Dependent case loses a lot of information here. And probably 6672 // leaks like a sieve. 6673 for (unsigned i = 0; i != NumComponents; ++i) { 6674 const OffsetOfComponent &OC = CompPtr[i]; 6675 if (OC.isBrackets) { 6676 // Offset of an array sub-field. TODO: Should we allow vector elements? 6677 const ArrayType *AT = Context.getAsArrayType(Res->getType()); 6678 if (!AT) { 6679 Res->Destroy(Context); 6680 return ExprError(Diag(OC.LocEnd, diag::err_offsetof_array_type) 6681 << Res->getType()); 6682 } 6683 6684 // FIXME: C++: Verify that operator[] isn't overloaded. 6685 6686 // Promote the array so it looks more like a normal array subscript 6687 // expression. 6688 DefaultFunctionArrayLvalueConversion(Res); 6689 6690 // C99 6.5.2.1p1 6691 Expr *Idx = static_cast<Expr*>(OC.U.E); 6692 // FIXME: Leaks Res 6693 if (!Idx->isTypeDependent() && !Idx->getType()->isIntegerType()) 6694 return ExprError(Diag(Idx->getLocStart(), 6695 diag::err_typecheck_subscript_not_integer) 6696 << Idx->getSourceRange()); 6697 6698 Res = new (Context) ArraySubscriptExpr(Res, Idx, AT->getElementType(), 6699 OC.LocEnd); 6700 continue; 6701 } 6702 6703 const RecordType *RC = Res->getType()->getAs<RecordType>(); 6704 if (!RC) { 6705 Res->Destroy(Context); 6706 return ExprError(Diag(OC.LocEnd, diag::err_offsetof_record_type) 6707 << Res->getType()); 6708 } 6709 6710 // Get the decl corresponding to this. 6711 RecordDecl *RD = RC->getDecl(); 6712 if (CXXRecordDecl *CRD = dyn_cast<CXXRecordDecl>(RD)) { 6713 if (!CRD->isPOD() && !DidWarnAboutNonPOD && 6714 DiagRuntimeBehavior(BuiltinLoc, 6715 PDiag(diag::warn_offsetof_non_pod_type) 6716 << SourceRange(CompPtr[0].LocStart, OC.LocEnd) 6717 << Res->getType())) 6718 DidWarnAboutNonPOD = true; 6719 } 6720 6721 LookupResult R(*this, OC.U.IdentInfo, OC.LocStart, LookupMemberName); 6722 LookupQualifiedName(R, RD); 6723 6724 FieldDecl *MemberDecl = R.getAsSingle<FieldDecl>(); 6725 // FIXME: Leaks Res 6726 if (!MemberDecl) 6727 return ExprError(Diag(BuiltinLoc, diag::err_no_member) 6728 << OC.U.IdentInfo << RD << SourceRange(OC.LocStart, OC.LocEnd)); 6729 6730 // FIXME: C++: Verify that MemberDecl isn't a static field. 6731 // FIXME: Verify that MemberDecl isn't a bitfield. 6732 if (cast<RecordDecl>(MemberDecl->getDeclContext())->isAnonymousStructOrUnion()) { 6733 Res = BuildAnonymousStructUnionMemberReference( 6734 OC.LocEnd, MemberDecl, Res, OC.LocEnd).takeAs<Expr>(); 6735 } else { 6736 PerformObjectMemberConversion(Res, /*Qualifier=*/0, MemberDecl); 6737 // MemberDecl->getType() doesn't get the right qualifiers, but it 6738 // doesn't matter here. 6739 Res = new (Context) MemberExpr(Res, false, MemberDecl, OC.LocEnd, 6740 MemberDecl->getType().getNonReferenceType()); 6741 } 6742 } 6743 } 6744 6745 return Owned(new (Context) UnaryOperator(Res, UnaryOperator::OffsetOf, 6746 Context.getSizeType(), BuiltinLoc)); 6747} 6748 6749 6750Sema::OwningExprResult Sema::ActOnTypesCompatibleExpr(SourceLocation BuiltinLoc, 6751 TypeTy *arg1,TypeTy *arg2, 6752 SourceLocation RPLoc) { 6753 // FIXME: Preserve type source info. 6754 QualType argT1 = GetTypeFromParser(arg1); 6755 QualType argT2 = GetTypeFromParser(arg2); 6756 6757 assert((!argT1.isNull() && !argT2.isNull()) && "Missing type argument(s)"); 6758 6759 if (getLangOptions().CPlusPlus) { 6760 Diag(BuiltinLoc, diag::err_types_compatible_p_in_cplusplus) 6761 << SourceRange(BuiltinLoc, RPLoc); 6762 return ExprError(); 6763 } 6764 6765 return Owned(new (Context) TypesCompatibleExpr(Context.IntTy, BuiltinLoc, 6766 argT1, argT2, RPLoc)); 6767} 6768 6769Sema::OwningExprResult Sema::ActOnChooseExpr(SourceLocation BuiltinLoc, 6770 ExprArg cond, 6771 ExprArg expr1, ExprArg expr2, 6772 SourceLocation RPLoc) { 6773 Expr *CondExpr = static_cast<Expr*>(cond.get()); 6774 Expr *LHSExpr = static_cast<Expr*>(expr1.get()); 6775 Expr *RHSExpr = static_cast<Expr*>(expr2.get()); 6776 6777 assert((CondExpr && LHSExpr && RHSExpr) && "Missing type argument(s)"); 6778 6779 QualType resType; 6780 bool ValueDependent = false; 6781 if (CondExpr->isTypeDependent() || CondExpr->isValueDependent()) { 6782 resType = Context.DependentTy; 6783 ValueDependent = true; 6784 } else { 6785 // The conditional expression is required to be a constant expression. 6786 llvm::APSInt condEval(32); 6787 SourceLocation ExpLoc; 6788 if (!CondExpr->isIntegerConstantExpr(condEval, Context, &ExpLoc)) 6789 return ExprError(Diag(ExpLoc, 6790 diag::err_typecheck_choose_expr_requires_constant) 6791 << CondExpr->getSourceRange()); 6792 6793 // If the condition is > zero, then the AST type is the same as the LSHExpr. 6794 resType = condEval.getZExtValue() ? LHSExpr->getType() : RHSExpr->getType(); 6795 ValueDependent = condEval.getZExtValue() ? LHSExpr->isValueDependent() 6796 : RHSExpr->isValueDependent(); 6797 } 6798 6799 cond.release(); expr1.release(); expr2.release(); 6800 return Owned(new (Context) ChooseExpr(BuiltinLoc, CondExpr, LHSExpr, RHSExpr, 6801 resType, RPLoc, 6802 resType->isDependentType(), 6803 ValueDependent)); 6804} 6805 6806//===----------------------------------------------------------------------===// 6807// Clang Extensions. 6808//===----------------------------------------------------------------------===// 6809 6810/// ActOnBlockStart - This callback is invoked when a block literal is started. 6811void Sema::ActOnBlockStart(SourceLocation CaretLoc, Scope *BlockScope) { 6812 BlockDecl *Block = BlockDecl::Create(Context, CurContext, CaretLoc); 6813 PushBlockScope(BlockScope, Block); 6814 CurContext->addDecl(Block); 6815 PushDeclContext(BlockScope, Block); 6816} 6817 6818void Sema::ActOnBlockArguments(Declarator &ParamInfo, Scope *CurScope) { 6819 assert(ParamInfo.getIdentifier()==0 && "block-id should have no identifier!"); 6820 BlockScopeInfo *CurBlock = getCurBlock(); 6821 6822 if (ParamInfo.getNumTypeObjects() == 0 6823 || ParamInfo.getTypeObject(0).Kind != DeclaratorChunk::Function) { 6824 ProcessDeclAttributes(CurScope, CurBlock->TheDecl, ParamInfo); 6825 QualType T = GetTypeForDeclarator(ParamInfo, CurScope); 6826 6827 if (T->isArrayType()) { 6828 Diag(ParamInfo.getSourceRange().getBegin(), 6829 diag::err_block_returns_array); 6830 return; 6831 } 6832 6833 // The parameter list is optional, if there was none, assume (). 6834 if (!T->isFunctionType()) 6835 T = Context.getFunctionType(T, 0, 0, false, 0, false, false, 0, 0, false, 6836 CC_Default); 6837 6838 CurBlock->hasPrototype = true; 6839 CurBlock->isVariadic = false; 6840 // Check for a valid sentinel attribute on this block. 6841 if (CurBlock->TheDecl->getAttr<SentinelAttr>()) { 6842 Diag(ParamInfo.getAttributes()->getLoc(), 6843 diag::warn_attribute_sentinel_not_variadic) << 1; 6844 // FIXME: remove the attribute. 6845 } 6846 QualType RetTy = T.getTypePtr()->getAs<FunctionType>()->getResultType(); 6847 6848 // Do not allow returning a objc interface by-value. 6849 if (RetTy->isObjCInterfaceType()) { 6850 Diag(ParamInfo.getSourceRange().getBegin(), 6851 diag::err_object_cannot_be_passed_returned_by_value) << 0 << RetTy; 6852 return; 6853 } 6854 6855 CurBlock->ReturnType = RetTy; 6856 return; 6857 } 6858 6859 // Analyze arguments to block. 6860 assert(ParamInfo.getTypeObject(0).Kind == DeclaratorChunk::Function && 6861 "Not a function declarator!"); 6862 DeclaratorChunk::FunctionTypeInfo &FTI = ParamInfo.getTypeObject(0).Fun; 6863 6864 CurBlock->hasPrototype = FTI.hasPrototype; 6865 CurBlock->isVariadic = true; 6866 6867 // Check for C99 6.7.5.3p10 - foo(void) is a non-varargs function that takes 6868 // no arguments, not a function that takes a single void argument. 6869 if (FTI.hasPrototype && 6870 FTI.NumArgs == 1 && !FTI.isVariadic && FTI.ArgInfo[0].Ident == 0 && 6871 (!FTI.ArgInfo[0].Param.getAs<ParmVarDecl>()->getType().getCVRQualifiers()&& 6872 FTI.ArgInfo[0].Param.getAs<ParmVarDecl>()->getType()->isVoidType())) { 6873 // empty arg list, don't push any params. 6874 CurBlock->isVariadic = false; 6875 } else if (FTI.hasPrototype) { 6876 for (unsigned i = 0, e = FTI.NumArgs; i != e; ++i) { 6877 ParmVarDecl *Param = FTI.ArgInfo[i].Param.getAs<ParmVarDecl>(); 6878 if (Param->getIdentifier() == 0 && 6879 !Param->isImplicit() && 6880 !Param->isInvalidDecl() && 6881 !getLangOptions().CPlusPlus) 6882 Diag(Param->getLocation(), diag::err_parameter_name_omitted); 6883 CurBlock->Params.push_back(Param); 6884 } 6885 CurBlock->isVariadic = FTI.isVariadic; 6886 } 6887 CurBlock->TheDecl->setParams(CurBlock->Params.data(), 6888 CurBlock->Params.size()); 6889 CurBlock->TheDecl->setIsVariadic(CurBlock->isVariadic); 6890 ProcessDeclAttributes(CurScope, CurBlock->TheDecl, ParamInfo); 6891 for (BlockDecl::param_iterator AI = CurBlock->TheDecl->param_begin(), 6892 E = CurBlock->TheDecl->param_end(); AI != E; ++AI) { 6893 (*AI)->setOwningFunction(CurBlock->TheDecl); 6894 6895 // If this has an identifier, add it to the scope stack. 6896 if ((*AI)->getIdentifier()) 6897 PushOnScopeChains(*AI, CurBlock->TheScope); 6898 } 6899 6900 // Check for a valid sentinel attribute on this block. 6901 if (!CurBlock->isVariadic && 6902 CurBlock->TheDecl->getAttr<SentinelAttr>()) { 6903 Diag(ParamInfo.getAttributes()->getLoc(), 6904 diag::warn_attribute_sentinel_not_variadic) << 1; 6905 // FIXME: remove the attribute. 6906 } 6907 6908 // Analyze the return type. 6909 QualType T = GetTypeForDeclarator(ParamInfo, CurScope); 6910 QualType RetTy = T->getAs<FunctionType>()->getResultType(); 6911 6912 // Do not allow returning a objc interface by-value. 6913 if (RetTy->isObjCInterfaceType()) { 6914 Diag(ParamInfo.getSourceRange().getBegin(), 6915 diag::err_object_cannot_be_passed_returned_by_value) << 0 << RetTy; 6916 } else if (!RetTy->isDependentType()) 6917 CurBlock->ReturnType = RetTy; 6918} 6919 6920/// ActOnBlockError - If there is an error parsing a block, this callback 6921/// is invoked to pop the information about the block from the action impl. 6922void Sema::ActOnBlockError(SourceLocation CaretLoc, Scope *CurScope) { 6923 // Pop off CurBlock, handle nested blocks. 6924 PopDeclContext(); 6925 PopFunctionOrBlockScope(); 6926 // FIXME: Delete the ParmVarDecl objects as well??? 6927} 6928 6929/// ActOnBlockStmtExpr - This is called when the body of a block statement 6930/// literal was successfully completed. ^(int x){...} 6931Sema::OwningExprResult Sema::ActOnBlockStmtExpr(SourceLocation CaretLoc, 6932 StmtArg body, Scope *CurScope) { 6933 // If blocks are disabled, emit an error. 6934 if (!LangOpts.Blocks) 6935 Diag(CaretLoc, diag::err_blocks_disable); 6936 6937 BlockScopeInfo *BSI = cast<BlockScopeInfo>(FunctionScopes.back()); 6938 6939 PopDeclContext(); 6940 6941 QualType RetTy = Context.VoidTy; 6942 if (!BSI->ReturnType.isNull()) 6943 RetTy = BSI->ReturnType; 6944 6945 llvm::SmallVector<QualType, 8> ArgTypes; 6946 for (unsigned i = 0, e = BSI->Params.size(); i != e; ++i) 6947 ArgTypes.push_back(BSI->Params[i]->getType()); 6948 6949 bool NoReturn = BSI->TheDecl->getAttr<NoReturnAttr>(); 6950 QualType BlockTy; 6951 if (!BSI->hasPrototype) 6952 BlockTy = Context.getFunctionType(RetTy, 0, 0, false, 0, false, false, 0, 0, 6953 NoReturn, CC_Default); 6954 else 6955 BlockTy = Context.getFunctionType(RetTy, ArgTypes.data(), ArgTypes.size(), 6956 BSI->isVariadic, 0, false, false, 0, 0, 6957 NoReturn, CC_Default); 6958 6959 // FIXME: Check that return/parameter types are complete/non-abstract 6960 DiagnoseUnusedParameters(BSI->Params.begin(), BSI->Params.end()); 6961 BlockTy = Context.getBlockPointerType(BlockTy); 6962 6963 // If needed, diagnose invalid gotos and switches in the block. 6964 if (FunctionNeedsScopeChecking() && !hasAnyErrorsInThisFunction()) 6965 DiagnoseInvalidJumps(static_cast<CompoundStmt*>(body.get())); 6966 6967 BSI->TheDecl->setBody(body.takeAs<CompoundStmt>()); 6968 6969 bool Good = true; 6970 // Check goto/label use. 6971 for (llvm::DenseMap<IdentifierInfo*, LabelStmt*>::iterator 6972 I = BSI->LabelMap.begin(), E = BSI->LabelMap.end(); I != E; ++I) { 6973 LabelStmt *L = I->second; 6974 6975 // Verify that we have no forward references left. If so, there was a goto 6976 // or address of a label taken, but no definition of it. 6977 if (L->getSubStmt() != 0) 6978 continue; 6979 6980 // Emit error. 6981 Diag(L->getIdentLoc(), diag::err_undeclared_label_use) << L->getName(); 6982 Good = false; 6983 } 6984 if (!Good) { 6985 PopFunctionOrBlockScope(); 6986 return ExprError(); 6987 } 6988 6989 AnalysisContext AC(BSI->TheDecl); 6990 CheckFallThroughForBlock(BlockTy, BSI->TheDecl->getBody(), AC); 6991 CheckUnreachable(AC); 6992 Expr *Result = new (Context) BlockExpr(BSI->TheDecl, BlockTy, 6993 BSI->hasBlockDeclRefExprs); 6994 PopFunctionOrBlockScope(); 6995 return Owned(Result); 6996} 6997 6998Sema::OwningExprResult Sema::ActOnVAArg(SourceLocation BuiltinLoc, 6999 ExprArg expr, TypeTy *type, 7000 SourceLocation RPLoc) { 7001 QualType T = GetTypeFromParser(type); 7002 Expr *E = static_cast<Expr*>(expr.get()); 7003 Expr *OrigExpr = E; 7004 7005 InitBuiltinVaListType(); 7006 7007 // Get the va_list type 7008 QualType VaListType = Context.getBuiltinVaListType(); 7009 if (VaListType->isArrayType()) { 7010 // Deal with implicit array decay; for example, on x86-64, 7011 // va_list is an array, but it's supposed to decay to 7012 // a pointer for va_arg. 7013 VaListType = Context.getArrayDecayedType(VaListType); 7014 // Make sure the input expression also decays appropriately. 7015 UsualUnaryConversions(E); 7016 } else { 7017 // Otherwise, the va_list argument must be an l-value because 7018 // it is modified by va_arg. 7019 if (!E->isTypeDependent() && 7020 CheckForModifiableLvalue(E, BuiltinLoc, *this)) 7021 return ExprError(); 7022 } 7023 7024 if (!E->isTypeDependent() && 7025 !Context.hasSameType(VaListType, E->getType())) { 7026 return ExprError(Diag(E->getLocStart(), 7027 diag::err_first_argument_to_va_arg_not_of_type_va_list) 7028 << OrigExpr->getType() << E->getSourceRange()); 7029 } 7030 7031 // FIXME: Check that type is complete/non-abstract 7032 // FIXME: Warn if a non-POD type is passed in. 7033 7034 expr.release(); 7035 return Owned(new (Context) VAArgExpr(BuiltinLoc, E, T.getNonReferenceType(), 7036 RPLoc)); 7037} 7038 7039Sema::OwningExprResult Sema::ActOnGNUNullExpr(SourceLocation TokenLoc) { 7040 // The type of __null will be int or long, depending on the size of 7041 // pointers on the target. 7042 QualType Ty; 7043 if (Context.Target.getPointerWidth(0) == Context.Target.getIntWidth()) 7044 Ty = Context.IntTy; 7045 else 7046 Ty = Context.LongTy; 7047 7048 return Owned(new (Context) GNUNullExpr(Ty, TokenLoc)); 7049} 7050 7051static void 7052MakeObjCStringLiteralCodeModificationHint(Sema& SemaRef, 7053 QualType DstType, 7054 Expr *SrcExpr, 7055 CodeModificationHint &Hint) { 7056 if (!SemaRef.getLangOptions().ObjC1) 7057 return; 7058 7059 const ObjCObjectPointerType *PT = DstType->getAs<ObjCObjectPointerType>(); 7060 if (!PT) 7061 return; 7062 7063 // Check if the destination is of type 'id'. 7064 if (!PT->isObjCIdType()) { 7065 // Check if the destination is the 'NSString' interface. 7066 const ObjCInterfaceDecl *ID = PT->getInterfaceDecl(); 7067 if (!ID || !ID->getIdentifier()->isStr("NSString")) 7068 return; 7069 } 7070 7071 // Strip off any parens and casts. 7072 StringLiteral *SL = dyn_cast<StringLiteral>(SrcExpr->IgnoreParenCasts()); 7073 if (!SL || SL->isWide()) 7074 return; 7075 7076 Hint = CodeModificationHint::CreateInsertion(SL->getLocStart(), "@"); 7077} 7078 7079bool Sema::DiagnoseAssignmentResult(AssignConvertType ConvTy, 7080 SourceLocation Loc, 7081 QualType DstType, QualType SrcType, 7082 Expr *SrcExpr, AssignmentAction Action) { 7083 // Decode the result (notice that AST's are still created for extensions). 7084 bool isInvalid = false; 7085 unsigned DiagKind; 7086 CodeModificationHint Hint; 7087 7088 switch (ConvTy) { 7089 default: assert(0 && "Unknown conversion type"); 7090 case Compatible: return false; 7091 case PointerToInt: 7092 DiagKind = diag::ext_typecheck_convert_pointer_int; 7093 break; 7094 case IntToPointer: 7095 DiagKind = diag::ext_typecheck_convert_int_pointer; 7096 break; 7097 case IncompatiblePointer: 7098 MakeObjCStringLiteralCodeModificationHint(*this, DstType, SrcExpr, Hint); 7099 DiagKind = diag::ext_typecheck_convert_incompatible_pointer; 7100 break; 7101 case IncompatiblePointerSign: 7102 DiagKind = diag::ext_typecheck_convert_incompatible_pointer_sign; 7103 break; 7104 case FunctionVoidPointer: 7105 DiagKind = diag::ext_typecheck_convert_pointer_void_func; 7106 break; 7107 case CompatiblePointerDiscardsQualifiers: 7108 // If the qualifiers lost were because we were applying the 7109 // (deprecated) C++ conversion from a string literal to a char* 7110 // (or wchar_t*), then there was no error (C++ 4.2p2). FIXME: 7111 // Ideally, this check would be performed in 7112 // CheckPointerTypesForAssignment. However, that would require a 7113 // bit of refactoring (so that the second argument is an 7114 // expression, rather than a type), which should be done as part 7115 // of a larger effort to fix CheckPointerTypesForAssignment for 7116 // C++ semantics. 7117 if (getLangOptions().CPlusPlus && 7118 IsStringLiteralToNonConstPointerConversion(SrcExpr, DstType)) 7119 return false; 7120 DiagKind = diag::ext_typecheck_convert_discards_qualifiers; 7121 break; 7122 case IncompatibleNestedPointerQualifiers: 7123 DiagKind = diag::ext_nested_pointer_qualifier_mismatch; 7124 break; 7125 case IntToBlockPointer: 7126 DiagKind = diag::err_int_to_block_pointer; 7127 break; 7128 case IncompatibleBlockPointer: 7129 DiagKind = diag::err_typecheck_convert_incompatible_block_pointer; 7130 break; 7131 case IncompatibleObjCQualifiedId: 7132 // FIXME: Diagnose the problem in ObjCQualifiedIdTypesAreCompatible, since 7133 // it can give a more specific diagnostic. 7134 DiagKind = diag::warn_incompatible_qualified_id; 7135 break; 7136 case IncompatibleVectors: 7137 DiagKind = diag::warn_incompatible_vectors; 7138 break; 7139 case Incompatible: 7140 DiagKind = diag::err_typecheck_convert_incompatible; 7141 isInvalid = true; 7142 break; 7143 } 7144 7145 Diag(Loc, DiagKind) << DstType << SrcType << Action 7146 << SrcExpr->getSourceRange() << Hint; 7147 return isInvalid; 7148} 7149 7150bool Sema::VerifyIntegerConstantExpression(const Expr *E, llvm::APSInt *Result){ 7151 llvm::APSInt ICEResult; 7152 if (E->isIntegerConstantExpr(ICEResult, Context)) { 7153 if (Result) 7154 *Result = ICEResult; 7155 return false; 7156 } 7157 7158 Expr::EvalResult EvalResult; 7159 7160 if (!E->Evaluate(EvalResult, Context) || !EvalResult.Val.isInt() || 7161 EvalResult.HasSideEffects) { 7162 Diag(E->getExprLoc(), diag::err_expr_not_ice) << E->getSourceRange(); 7163 7164 if (EvalResult.Diag) { 7165 // We only show the note if it's not the usual "invalid subexpression" 7166 // or if it's actually in a subexpression. 7167 if (EvalResult.Diag != diag::note_invalid_subexpr_in_ice || 7168 E->IgnoreParens() != EvalResult.DiagExpr->IgnoreParens()) 7169 Diag(EvalResult.DiagLoc, EvalResult.Diag); 7170 } 7171 7172 return true; 7173 } 7174 7175 Diag(E->getExprLoc(), diag::ext_expr_not_ice) << 7176 E->getSourceRange(); 7177 7178 if (EvalResult.Diag && 7179 Diags.getDiagnosticLevel(diag::ext_expr_not_ice) != Diagnostic::Ignored) 7180 Diag(EvalResult.DiagLoc, EvalResult.Diag); 7181 7182 if (Result) 7183 *Result = EvalResult.Val.getInt(); 7184 return false; 7185} 7186 7187void 7188Sema::PushExpressionEvaluationContext(ExpressionEvaluationContext NewContext) { 7189 ExprEvalContexts.push_back( 7190 ExpressionEvaluationContextRecord(NewContext, ExprTemporaries.size())); 7191} 7192 7193void 7194Sema::PopExpressionEvaluationContext() { 7195 // Pop the current expression evaluation context off the stack. 7196 ExpressionEvaluationContextRecord Rec = ExprEvalContexts.back(); 7197 ExprEvalContexts.pop_back(); 7198 7199 if (Rec.Context == PotentiallyPotentiallyEvaluated) { 7200 if (Rec.PotentiallyReferenced) { 7201 // Mark any remaining declarations in the current position of the stack 7202 // as "referenced". If they were not meant to be referenced, semantic 7203 // analysis would have eliminated them (e.g., in ActOnCXXTypeId). 7204 for (PotentiallyReferencedDecls::iterator 7205 I = Rec.PotentiallyReferenced->begin(), 7206 IEnd = Rec.PotentiallyReferenced->end(); 7207 I != IEnd; ++I) 7208 MarkDeclarationReferenced(I->first, I->second); 7209 } 7210 7211 if (Rec.PotentiallyDiagnosed) { 7212 // Emit any pending diagnostics. 7213 for (PotentiallyEmittedDiagnostics::iterator 7214 I = Rec.PotentiallyDiagnosed->begin(), 7215 IEnd = Rec.PotentiallyDiagnosed->end(); 7216 I != IEnd; ++I) 7217 Diag(I->first, I->second); 7218 } 7219 } 7220 7221 // When are coming out of an unevaluated context, clear out any 7222 // temporaries that we may have created as part of the evaluation of 7223 // the expression in that context: they aren't relevant because they 7224 // will never be constructed. 7225 if (Rec.Context == Unevaluated && 7226 ExprTemporaries.size() > Rec.NumTemporaries) 7227 ExprTemporaries.erase(ExprTemporaries.begin() + Rec.NumTemporaries, 7228 ExprTemporaries.end()); 7229 7230 // Destroy the popped expression evaluation record. 7231 Rec.Destroy(); 7232} 7233 7234/// \brief Note that the given declaration was referenced in the source code. 7235/// 7236/// This routine should be invoke whenever a given declaration is referenced 7237/// in the source code, and where that reference occurred. If this declaration 7238/// reference means that the the declaration is used (C++ [basic.def.odr]p2, 7239/// C99 6.9p3), then the declaration will be marked as used. 7240/// 7241/// \param Loc the location where the declaration was referenced. 7242/// 7243/// \param D the declaration that has been referenced by the source code. 7244void Sema::MarkDeclarationReferenced(SourceLocation Loc, Decl *D) { 7245 assert(D && "No declaration?"); 7246 7247 if (D->isUsed()) 7248 return; 7249 7250 // Mark a parameter or variable declaration "used", regardless of whether we're in a 7251 // template or not. The reason for this is that unevaluated expressions 7252 // (e.g. (void)sizeof()) constitute a use for warning purposes (-Wunused-variables and 7253 // -Wunused-parameters) 7254 if (isa<ParmVarDecl>(D) || 7255 (isa<VarDecl>(D) && D->getDeclContext()->isFunctionOrMethod())) 7256 D->setUsed(true); 7257 7258 // Do not mark anything as "used" within a dependent context; wait for 7259 // an instantiation. 7260 if (CurContext->isDependentContext()) 7261 return; 7262 7263 switch (ExprEvalContexts.back().Context) { 7264 case Unevaluated: 7265 // We are in an expression that is not potentially evaluated; do nothing. 7266 return; 7267 7268 case PotentiallyEvaluated: 7269 // We are in a potentially-evaluated expression, so this declaration is 7270 // "used"; handle this below. 7271 break; 7272 7273 case PotentiallyPotentiallyEvaluated: 7274 // We are in an expression that may be potentially evaluated; queue this 7275 // declaration reference until we know whether the expression is 7276 // potentially evaluated. 7277 ExprEvalContexts.back().addReferencedDecl(Loc, D); 7278 return; 7279 } 7280 7281 // Note that this declaration has been used. 7282 if (CXXConstructorDecl *Constructor = dyn_cast<CXXConstructorDecl>(D)) { 7283 unsigned TypeQuals; 7284 if (Constructor->isImplicit() && Constructor->isDefaultConstructor()) { 7285 if (!Constructor->isUsed()) 7286 DefineImplicitDefaultConstructor(Loc, Constructor); 7287 } else if (Constructor->isImplicit() && 7288 Constructor->isCopyConstructor(TypeQuals)) { 7289 if (!Constructor->isUsed()) 7290 DefineImplicitCopyConstructor(Loc, Constructor, TypeQuals); 7291 } 7292 7293 MaybeMarkVirtualMembersReferenced(Loc, Constructor); 7294 } else if (CXXDestructorDecl *Destructor = dyn_cast<CXXDestructorDecl>(D)) { 7295 if (Destructor->isImplicit() && !Destructor->isUsed()) 7296 DefineImplicitDestructor(Loc, Destructor); 7297 7298 } else if (CXXMethodDecl *MethodDecl = dyn_cast<CXXMethodDecl>(D)) { 7299 if (MethodDecl->isImplicit() && MethodDecl->isOverloadedOperator() && 7300 MethodDecl->getOverloadedOperator() == OO_Equal) { 7301 if (!MethodDecl->isUsed()) 7302 DefineImplicitOverloadedAssign(Loc, MethodDecl); 7303 } 7304 } 7305 if (FunctionDecl *Function = dyn_cast<FunctionDecl>(D)) { 7306 // Implicit instantiation of function templates and member functions of 7307 // class templates. 7308 if (!Function->getBody() && Function->isImplicitlyInstantiable()) { 7309 bool AlreadyInstantiated = false; 7310 if (FunctionTemplateSpecializationInfo *SpecInfo 7311 = Function->getTemplateSpecializationInfo()) { 7312 if (SpecInfo->getPointOfInstantiation().isInvalid()) 7313 SpecInfo->setPointOfInstantiation(Loc); 7314 else if (SpecInfo->getTemplateSpecializationKind() 7315 == TSK_ImplicitInstantiation) 7316 AlreadyInstantiated = true; 7317 } else if (MemberSpecializationInfo *MSInfo 7318 = Function->getMemberSpecializationInfo()) { 7319 if (MSInfo->getPointOfInstantiation().isInvalid()) 7320 MSInfo->setPointOfInstantiation(Loc); 7321 else if (MSInfo->getTemplateSpecializationKind() 7322 == TSK_ImplicitInstantiation) 7323 AlreadyInstantiated = true; 7324 } 7325 7326 if (!AlreadyInstantiated) { 7327 if (isa<CXXRecordDecl>(Function->getDeclContext()) && 7328 cast<CXXRecordDecl>(Function->getDeclContext())->isLocalClass()) 7329 PendingLocalImplicitInstantiations.push_back(std::make_pair(Function, 7330 Loc)); 7331 else 7332 PendingImplicitInstantiations.push_back(std::make_pair(Function, 7333 Loc)); 7334 } 7335 } 7336 7337 // FIXME: keep track of references to static functions 7338 Function->setUsed(true); 7339 7340 return; 7341 } 7342 7343 if (VarDecl *Var = dyn_cast<VarDecl>(D)) { 7344 // Implicit instantiation of static data members of class templates. 7345 if (Var->isStaticDataMember() && 7346 Var->getInstantiatedFromStaticDataMember()) { 7347 MemberSpecializationInfo *MSInfo = Var->getMemberSpecializationInfo(); 7348 assert(MSInfo && "Missing member specialization information?"); 7349 if (MSInfo->getPointOfInstantiation().isInvalid() && 7350 MSInfo->getTemplateSpecializationKind()== TSK_ImplicitInstantiation) { 7351 MSInfo->setPointOfInstantiation(Loc); 7352 PendingImplicitInstantiations.push_back(std::make_pair(Var, Loc)); 7353 } 7354 } 7355 7356 // FIXME: keep track of references to static data? 7357 7358 D->setUsed(true); 7359 return; 7360 } 7361} 7362 7363/// \brief Emit a diagnostic that describes an effect on the run-time behavior 7364/// of the program being compiled. 7365/// 7366/// This routine emits the given diagnostic when the code currently being 7367/// type-checked is "potentially evaluated", meaning that there is a 7368/// possibility that the code will actually be executable. Code in sizeof() 7369/// expressions, code used only during overload resolution, etc., are not 7370/// potentially evaluated. This routine will suppress such diagnostics or, 7371/// in the absolutely nutty case of potentially potentially evaluated 7372/// expressions (C++ typeid), queue the diagnostic to potentially emit it 7373/// later. 7374/// 7375/// This routine should be used for all diagnostics that describe the run-time 7376/// behavior of a program, such as passing a non-POD value through an ellipsis. 7377/// Failure to do so will likely result in spurious diagnostics or failures 7378/// during overload resolution or within sizeof/alignof/typeof/typeid. 7379bool Sema::DiagRuntimeBehavior(SourceLocation Loc, 7380 const PartialDiagnostic &PD) { 7381 switch (ExprEvalContexts.back().Context ) { 7382 case Unevaluated: 7383 // The argument will never be evaluated, so don't complain. 7384 break; 7385 7386 case PotentiallyEvaluated: 7387 Diag(Loc, PD); 7388 return true; 7389 7390 case PotentiallyPotentiallyEvaluated: 7391 ExprEvalContexts.back().addDiagnostic(Loc, PD); 7392 break; 7393 } 7394 7395 return false; 7396} 7397 7398bool Sema::CheckCallReturnType(QualType ReturnType, SourceLocation Loc, 7399 CallExpr *CE, FunctionDecl *FD) { 7400 if (ReturnType->isVoidType() || !ReturnType->isIncompleteType()) 7401 return false; 7402 7403 PartialDiagnostic Note = 7404 FD ? PDiag(diag::note_function_with_incomplete_return_type_declared_here) 7405 << FD->getDeclName() : PDiag(); 7406 SourceLocation NoteLoc = FD ? FD->getLocation() : SourceLocation(); 7407 7408 if (RequireCompleteType(Loc, ReturnType, 7409 FD ? 7410 PDiag(diag::err_call_function_incomplete_return) 7411 << CE->getSourceRange() << FD->getDeclName() : 7412 PDiag(diag::err_call_incomplete_return) 7413 << CE->getSourceRange(), 7414 std::make_pair(NoteLoc, Note))) 7415 return true; 7416 7417 return false; 7418} 7419 7420// Diagnose the common s/=/==/ typo. Note that adding parentheses 7421// will prevent this condition from triggering, which is what we want. 7422void Sema::DiagnoseAssignmentAsCondition(Expr *E) { 7423 SourceLocation Loc; 7424 7425 unsigned diagnostic = diag::warn_condition_is_assignment; 7426 7427 if (isa<BinaryOperator>(E)) { 7428 BinaryOperator *Op = cast<BinaryOperator>(E); 7429 if (Op->getOpcode() != BinaryOperator::Assign) 7430 return; 7431 7432 // Greylist some idioms by putting them into a warning subcategory. 7433 if (ObjCMessageExpr *ME 7434 = dyn_cast<ObjCMessageExpr>(Op->getRHS()->IgnoreParenCasts())) { 7435 Selector Sel = ME->getSelector(); 7436 7437 // self = [<foo> init...] 7438 if (isSelfExpr(Op->getLHS()) 7439 && Sel.getIdentifierInfoForSlot(0)->getName().startswith("init")) 7440 diagnostic = diag::warn_condition_is_idiomatic_assignment; 7441 7442 // <foo> = [<bar> nextObject] 7443 else if (Sel.isUnarySelector() && 7444 Sel.getIdentifierInfoForSlot(0)->getName() == "nextObject") 7445 diagnostic = diag::warn_condition_is_idiomatic_assignment; 7446 } 7447 7448 Loc = Op->getOperatorLoc(); 7449 } else if (isa<CXXOperatorCallExpr>(E)) { 7450 CXXOperatorCallExpr *Op = cast<CXXOperatorCallExpr>(E); 7451 if (Op->getOperator() != OO_Equal) 7452 return; 7453 7454 Loc = Op->getOperatorLoc(); 7455 } else { 7456 // Not an assignment. 7457 return; 7458 } 7459 7460 SourceLocation Open = E->getSourceRange().getBegin(); 7461 SourceLocation Close = PP.getLocForEndOfToken(E->getSourceRange().getEnd()); 7462 7463 Diag(Loc, diagnostic) 7464 << E->getSourceRange() 7465 << CodeModificationHint::CreateInsertion(Open, "(") 7466 << CodeModificationHint::CreateInsertion(Close, ")"); 7467 Diag(Loc, diag::note_condition_assign_to_comparison) 7468 << CodeModificationHint::CreateReplacement(Loc, "=="); 7469} 7470 7471bool Sema::CheckBooleanCondition(Expr *&E, SourceLocation Loc) { 7472 DiagnoseAssignmentAsCondition(E); 7473 7474 if (!E->isTypeDependent()) { 7475 DefaultFunctionArrayLvalueConversion(E); 7476 7477 QualType T = E->getType(); 7478 7479 if (getLangOptions().CPlusPlus) { 7480 if (CheckCXXBooleanCondition(E)) // C++ 6.4p4 7481 return true; 7482 } else if (!T->isScalarType()) { // C99 6.8.4.1p1 7483 Diag(Loc, diag::err_typecheck_statement_requires_scalar) 7484 << T << E->getSourceRange(); 7485 return true; 7486 } 7487 } 7488 7489 return false; 7490} 7491