SemaExpr.cpp revision 349f08701b41fd9991d80ab14dabccb4897c3eac
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/PathSensitive/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} 202 203/// UsualUnaryConversions - Performs various conversions that are common to most 204/// operators (C99 6.3). The conversions of array and function types are 205/// sometimes surpressed. For example, the array->pointer conversion doesn't 206/// apply if the array is an argument to the sizeof or address (&) operators. 207/// In these instances, this routine should *not* be called. 208Expr *Sema::UsualUnaryConversions(Expr *&Expr) { 209 QualType Ty = Expr->getType(); 210 assert(!Ty.isNull() && "UsualUnaryConversions - missing type"); 211 212 // C99 6.3.1.1p2: 213 // 214 // The following may be used in an expression wherever an int or 215 // unsigned int may be used: 216 // - an object or expression with an integer type whose integer 217 // conversion rank is less than or equal to the rank of int 218 // and unsigned int. 219 // - A bit-field of type _Bool, int, signed int, or unsigned int. 220 // 221 // If an int can represent all values of the original type, the 222 // value is converted to an int; otherwise, it is converted to an 223 // unsigned int. These are called the integer promotions. All 224 // other types are unchanged by the integer promotions. 225 QualType PTy = Context.isPromotableBitField(Expr); 226 if (!PTy.isNull()) { 227 ImpCastExprToType(Expr, PTy, CastExpr::CK_IntegralCast); 228 return Expr; 229 } 230 if (Ty->isPromotableIntegerType()) { 231 QualType PT = Context.getPromotedIntegerType(Ty); 232 ImpCastExprToType(Expr, PT, CastExpr::CK_IntegralCast); 233 return Expr; 234 } 235 236 DefaultFunctionArrayConversion(Expr); 237 return Expr; 238} 239 240/// DefaultArgumentPromotion (C99 6.5.2.2p6). Used for function calls that 241/// do not have a prototype. Arguments that have type float are promoted to 242/// double. All other argument types are converted by UsualUnaryConversions(). 243void Sema::DefaultArgumentPromotion(Expr *&Expr) { 244 QualType Ty = Expr->getType(); 245 assert(!Ty.isNull() && "DefaultArgumentPromotion - missing type"); 246 247 // If this is a 'float' (CVR qualified or typedef) promote to double. 248 if (const BuiltinType *BT = Ty->getAs<BuiltinType>()) 249 if (BT->getKind() == BuiltinType::Float) 250 return ImpCastExprToType(Expr, Context.DoubleTy, 251 CastExpr::CK_FloatingCast); 252 253 UsualUnaryConversions(Expr); 254} 255 256/// DefaultVariadicArgumentPromotion - Like DefaultArgumentPromotion, but 257/// will warn if the resulting type is not a POD type, and rejects ObjC 258/// interfaces passed by value. This returns true if the argument type is 259/// completely illegal. 260bool Sema::DefaultVariadicArgumentPromotion(Expr *&Expr, VariadicCallType CT) { 261 DefaultArgumentPromotion(Expr); 262 263 if (Expr->getType()->isObjCInterfaceType() && 264 DiagRuntimeBehavior(Expr->getLocStart(), 265 PDiag(diag::err_cannot_pass_objc_interface_to_vararg) 266 << Expr->getType() << CT)) 267 return true; 268 269 if (!Expr->getType()->isPODType() && 270 DiagRuntimeBehavior(Expr->getLocStart(), 271 PDiag(diag::warn_cannot_pass_non_pod_arg_to_vararg) 272 << Expr->getType() << CT)) 273 return true; 274 275 return false; 276} 277 278 279/// UsualArithmeticConversions - Performs various conversions that are common to 280/// binary operators (C99 6.3.1.8). If both operands aren't arithmetic, this 281/// routine returns the first non-arithmetic type found. The client is 282/// responsible for emitting appropriate error diagnostics. 283/// FIXME: verify the conversion rules for "complex int" are consistent with 284/// GCC. 285QualType Sema::UsualArithmeticConversions(Expr *&lhsExpr, Expr *&rhsExpr, 286 bool isCompAssign) { 287 if (!isCompAssign) 288 UsualUnaryConversions(lhsExpr); 289 290 UsualUnaryConversions(rhsExpr); 291 292 // For conversion purposes, we ignore any qualifiers. 293 // For example, "const float" and "float" are equivalent. 294 QualType lhs = 295 Context.getCanonicalType(lhsExpr->getType()).getUnqualifiedType(); 296 QualType rhs = 297 Context.getCanonicalType(rhsExpr->getType()).getUnqualifiedType(); 298 299 // If both types are identical, no conversion is needed. 300 if (lhs == rhs) 301 return lhs; 302 303 // If either side is a non-arithmetic type (e.g. a pointer), we are done. 304 // The caller can deal with this (e.g. pointer + int). 305 if (!lhs->isArithmeticType() || !rhs->isArithmeticType()) 306 return lhs; 307 308 // Perform bitfield promotions. 309 QualType LHSBitfieldPromoteTy = Context.isPromotableBitField(lhsExpr); 310 if (!LHSBitfieldPromoteTy.isNull()) 311 lhs = LHSBitfieldPromoteTy; 312 QualType RHSBitfieldPromoteTy = Context.isPromotableBitField(rhsExpr); 313 if (!RHSBitfieldPromoteTy.isNull()) 314 rhs = RHSBitfieldPromoteTy; 315 316 QualType destType = Context.UsualArithmeticConversionsType(lhs, rhs); 317 if (!isCompAssign) 318 ImpCastExprToType(lhsExpr, destType, CastExpr::CK_Unknown); 319 ImpCastExprToType(rhsExpr, destType, CastExpr::CK_Unknown); 320 return destType; 321} 322 323//===----------------------------------------------------------------------===// 324// Semantic Analysis for various Expression Types 325//===----------------------------------------------------------------------===// 326 327 328/// ActOnStringLiteral - The specified tokens were lexed as pasted string 329/// fragments (e.g. "foo" "bar" L"baz"). The result string has to handle string 330/// concatenation ([C99 5.1.1.2, translation phase #6]), so it may come from 331/// multiple tokens. However, the common case is that StringToks points to one 332/// string. 333/// 334Action::OwningExprResult 335Sema::ActOnStringLiteral(const Token *StringToks, unsigned NumStringToks) { 336 assert(NumStringToks && "Must have at least one string!"); 337 338 StringLiteralParser Literal(StringToks, NumStringToks, PP); 339 if (Literal.hadError) 340 return ExprError(); 341 342 llvm::SmallVector<SourceLocation, 4> StringTokLocs; 343 for (unsigned i = 0; i != NumStringToks; ++i) 344 StringTokLocs.push_back(StringToks[i].getLocation()); 345 346 QualType StrTy = Context.CharTy; 347 if (Literal.AnyWide) StrTy = Context.getWCharType(); 348 if (Literal.Pascal) StrTy = Context.UnsignedCharTy; 349 350 // A C++ string literal has a const-qualified element type (C++ 2.13.4p1). 351 if (getLangOptions().CPlusPlus) 352 StrTy.addConst(); 353 354 // Get an array type for the string, according to C99 6.4.5. This includes 355 // the nul terminator character as well as the string length for pascal 356 // strings. 357 StrTy = Context.getConstantArrayType(StrTy, 358 llvm::APInt(32, Literal.GetNumStringChars()+1), 359 ArrayType::Normal, 0); 360 361 // Pass &StringTokLocs[0], StringTokLocs.size() to factory! 362 return Owned(StringLiteral::Create(Context, Literal.GetString(), 363 Literal.GetStringLength(), 364 Literal.AnyWide, StrTy, 365 &StringTokLocs[0], 366 StringTokLocs.size())); 367} 368 369/// ShouldSnapshotBlockValueReference - Return true if a reference inside of 370/// CurBlock to VD should cause it to be snapshotted (as we do for auto 371/// variables defined outside the block) or false if this is not needed (e.g. 372/// for values inside the block or for globals). 373/// 374/// This also keeps the 'hasBlockDeclRefExprs' in the BlockSemaInfo records 375/// up-to-date. 376/// 377static bool ShouldSnapshotBlockValueReference(BlockSemaInfo *CurBlock, 378 ValueDecl *VD) { 379 // If the value is defined inside the block, we couldn't snapshot it even if 380 // we wanted to. 381 if (CurBlock->TheDecl == VD->getDeclContext()) 382 return false; 383 384 // If this is an enum constant or function, it is constant, don't snapshot. 385 if (isa<EnumConstantDecl>(VD) || isa<FunctionDecl>(VD)) 386 return false; 387 388 // If this is a reference to an extern, static, or global variable, no need to 389 // snapshot it. 390 // FIXME: What about 'const' variables in C++? 391 if (const VarDecl *Var = dyn_cast<VarDecl>(VD)) 392 if (!Var->hasLocalStorage()) 393 return false; 394 395 // Blocks that have these can't be constant. 396 CurBlock->hasBlockDeclRefExprs = true; 397 398 // If we have nested blocks, the decl may be declared in an outer block (in 399 // which case that outer block doesn't get "hasBlockDeclRefExprs") or it may 400 // be defined outside all of the current blocks (in which case the blocks do 401 // all get the bit). Walk the nesting chain. 402 for (BlockSemaInfo *NextBlock = CurBlock->PrevBlockInfo; NextBlock; 403 NextBlock = NextBlock->PrevBlockInfo) { 404 // If we found the defining block for the variable, don't mark the block as 405 // having a reference outside it. 406 if (NextBlock->TheDecl == VD->getDeclContext()) 407 break; 408 409 // Otherwise, the DeclRef from the inner block causes the outer one to need 410 // a snapshot as well. 411 NextBlock->hasBlockDeclRefExprs = true; 412 } 413 414 return true; 415} 416 417 418 419/// BuildDeclRefExpr - Build a DeclRefExpr. 420Sema::OwningExprResult 421Sema::BuildDeclRefExpr(ValueDecl *D, QualType Ty, SourceLocation Loc, 422 const CXXScopeSpec *SS) { 423 if (Context.getCanonicalType(Ty) == Context.UndeducedAutoTy) { 424 Diag(Loc, 425 diag::err_auto_variable_cannot_appear_in_own_initializer) 426 << D->getDeclName(); 427 return ExprError(); 428 } 429 430 if (const VarDecl *VD = dyn_cast<VarDecl>(D)) { 431 if (const CXXMethodDecl *MD = dyn_cast<CXXMethodDecl>(CurContext)) { 432 if (const FunctionDecl *FD = MD->getParent()->isLocalClass()) { 433 if (VD->hasLocalStorage() && VD->getDeclContext() != CurContext) { 434 Diag(Loc, diag::err_reference_to_local_var_in_enclosing_function) 435 << D->getIdentifier() << FD->getDeclName(); 436 Diag(D->getLocation(), diag::note_local_variable_declared_here) 437 << D->getIdentifier(); 438 return ExprError(); 439 } 440 } 441 } 442 } 443 444 MarkDeclarationReferenced(Loc, D); 445 446 return Owned(DeclRefExpr::Create(Context, 447 SS? (NestedNameSpecifier *)SS->getScopeRep() : 0, 448 SS? SS->getRange() : SourceRange(), 449 D, Loc, Ty)); 450} 451 452/// getObjectForAnonymousRecordDecl - Retrieve the (unnamed) field or 453/// variable corresponding to the anonymous union or struct whose type 454/// is Record. 455static Decl *getObjectForAnonymousRecordDecl(ASTContext &Context, 456 RecordDecl *Record) { 457 assert(Record->isAnonymousStructOrUnion() && 458 "Record must be an anonymous struct or union!"); 459 460 // FIXME: Once Decls are directly linked together, this will be an O(1) 461 // operation rather than a slow walk through DeclContext's vector (which 462 // itself will be eliminated). DeclGroups might make this even better. 463 DeclContext *Ctx = Record->getDeclContext(); 464 for (DeclContext::decl_iterator D = Ctx->decls_begin(), 465 DEnd = Ctx->decls_end(); 466 D != DEnd; ++D) { 467 if (*D == Record) { 468 // The object for the anonymous struct/union directly 469 // follows its type in the list of declarations. 470 ++D; 471 assert(D != DEnd && "Missing object for anonymous record"); 472 assert(!cast<NamedDecl>(*D)->getDeclName() && "Decl should be unnamed"); 473 return *D; 474 } 475 } 476 477 assert(false && "Missing object for anonymous record"); 478 return 0; 479} 480 481/// \brief Given a field that represents a member of an anonymous 482/// struct/union, build the path from that field's context to the 483/// actual member. 484/// 485/// Construct the sequence of field member references we'll have to 486/// perform to get to the field in the anonymous union/struct. The 487/// list of members is built from the field outward, so traverse it 488/// backwards to go from an object in the current context to the field 489/// we found. 490/// 491/// \returns The variable from which the field access should begin, 492/// for an anonymous struct/union that is not a member of another 493/// class. Otherwise, returns NULL. 494VarDecl *Sema::BuildAnonymousStructUnionMemberPath(FieldDecl *Field, 495 llvm::SmallVectorImpl<FieldDecl *> &Path) { 496 assert(Field->getDeclContext()->isRecord() && 497 cast<RecordDecl>(Field->getDeclContext())->isAnonymousStructOrUnion() 498 && "Field must be stored inside an anonymous struct or union"); 499 500 Path.push_back(Field); 501 VarDecl *BaseObject = 0; 502 DeclContext *Ctx = Field->getDeclContext(); 503 do { 504 RecordDecl *Record = cast<RecordDecl>(Ctx); 505 Decl *AnonObject = getObjectForAnonymousRecordDecl(Context, Record); 506 if (FieldDecl *AnonField = dyn_cast<FieldDecl>(AnonObject)) 507 Path.push_back(AnonField); 508 else { 509 BaseObject = cast<VarDecl>(AnonObject); 510 break; 511 } 512 Ctx = Ctx->getParent(); 513 } while (Ctx->isRecord() && 514 cast<RecordDecl>(Ctx)->isAnonymousStructOrUnion()); 515 516 return BaseObject; 517} 518 519Sema::OwningExprResult 520Sema::BuildAnonymousStructUnionMemberReference(SourceLocation Loc, 521 FieldDecl *Field, 522 Expr *BaseObjectExpr, 523 SourceLocation OpLoc) { 524 llvm::SmallVector<FieldDecl *, 4> AnonFields; 525 VarDecl *BaseObject = BuildAnonymousStructUnionMemberPath(Field, 526 AnonFields); 527 528 // Build the expression that refers to the base object, from 529 // which we will build a sequence of member references to each 530 // of the anonymous union objects and, eventually, the field we 531 // found via name lookup. 532 bool BaseObjectIsPointer = false; 533 Qualifiers BaseQuals; 534 if (BaseObject) { 535 // BaseObject is an anonymous struct/union variable (and is, 536 // therefore, not part of another non-anonymous record). 537 if (BaseObjectExpr) BaseObjectExpr->Destroy(Context); 538 MarkDeclarationReferenced(Loc, BaseObject); 539 BaseObjectExpr = new (Context) DeclRefExpr(BaseObject,BaseObject->getType(), 540 SourceLocation()); 541 BaseQuals 542 = Context.getCanonicalType(BaseObject->getType()).getQualifiers(); 543 } else if (BaseObjectExpr) { 544 // The caller provided the base object expression. Determine 545 // whether its a pointer and whether it adds any qualifiers to the 546 // anonymous struct/union fields we're looking into. 547 QualType ObjectType = BaseObjectExpr->getType(); 548 if (const PointerType *ObjectPtr = ObjectType->getAs<PointerType>()) { 549 BaseObjectIsPointer = true; 550 ObjectType = ObjectPtr->getPointeeType(); 551 } 552 BaseQuals 553 = Context.getCanonicalType(ObjectType).getQualifiers(); 554 } else { 555 // We've found a member of an anonymous struct/union that is 556 // inside a non-anonymous struct/union, so in a well-formed 557 // program our base object expression is "this". 558 if (CXXMethodDecl *MD = dyn_cast<CXXMethodDecl>(CurContext)) { 559 if (!MD->isStatic()) { 560 QualType AnonFieldType 561 = Context.getTagDeclType( 562 cast<RecordDecl>(AnonFields.back()->getDeclContext())); 563 QualType ThisType = Context.getTagDeclType(MD->getParent()); 564 if ((Context.getCanonicalType(AnonFieldType) 565 == Context.getCanonicalType(ThisType)) || 566 IsDerivedFrom(ThisType, AnonFieldType)) { 567 // Our base object expression is "this". 568 BaseObjectExpr = new (Context) CXXThisExpr(Loc, 569 MD->getThisType(Context), 570 /*isImplicit=*/true); 571 BaseObjectIsPointer = true; 572 } 573 } else { 574 return ExprError(Diag(Loc,diag::err_invalid_member_use_in_static_method) 575 << Field->getDeclName()); 576 } 577 BaseQuals = Qualifiers::fromCVRMask(MD->getTypeQualifiers()); 578 } 579 580 if (!BaseObjectExpr) 581 return ExprError(Diag(Loc, diag::err_invalid_non_static_member_use) 582 << Field->getDeclName()); 583 } 584 585 // Build the implicit member references to the field of the 586 // anonymous struct/union. 587 Expr *Result = BaseObjectExpr; 588 Qualifiers ResultQuals = BaseQuals; 589 for (llvm::SmallVector<FieldDecl *, 4>::reverse_iterator 590 FI = AnonFields.rbegin(), FIEnd = AnonFields.rend(); 591 FI != FIEnd; ++FI) { 592 QualType MemberType = (*FI)->getType(); 593 Qualifiers MemberTypeQuals = 594 Context.getCanonicalType(MemberType).getQualifiers(); 595 596 // CVR attributes from the base are picked up by members, 597 // except that 'mutable' members don't pick up 'const'. 598 if ((*FI)->isMutable()) 599 ResultQuals.removeConst(); 600 601 // GC attributes are never picked up by members. 602 ResultQuals.removeObjCGCAttr(); 603 604 // TR 18037 does not allow fields to be declared with address spaces. 605 assert(!MemberTypeQuals.hasAddressSpace()); 606 607 Qualifiers NewQuals = ResultQuals + MemberTypeQuals; 608 if (NewQuals != MemberTypeQuals) 609 MemberType = Context.getQualifiedType(MemberType, NewQuals); 610 611 MarkDeclarationReferenced(Loc, *FI); 612 PerformObjectMemberConversion(Result, *FI); 613 // FIXME: Might this end up being a qualified name? 614 Result = new (Context) MemberExpr(Result, BaseObjectIsPointer, *FI, 615 OpLoc, MemberType); 616 BaseObjectIsPointer = false; 617 ResultQuals = NewQuals; 618 } 619 620 return Owned(Result); 621} 622 623/// Decomposes the given name into a DeclarationName, its location, and 624/// possibly a list of template arguments. 625/// 626/// If this produces template arguments, it is permitted to call 627/// DecomposeTemplateName. 628/// 629/// This actually loses a lot of source location information for 630/// non-standard name kinds; we should consider preserving that in 631/// some way. 632static void DecomposeUnqualifiedId(Sema &SemaRef, 633 const UnqualifiedId &Id, 634 TemplateArgumentListInfo &Buffer, 635 DeclarationName &Name, 636 SourceLocation &NameLoc, 637 const TemplateArgumentListInfo *&TemplateArgs) { 638 if (Id.getKind() == UnqualifiedId::IK_TemplateId) { 639 Buffer.setLAngleLoc(Id.TemplateId->LAngleLoc); 640 Buffer.setRAngleLoc(Id.TemplateId->RAngleLoc); 641 642 ASTTemplateArgsPtr TemplateArgsPtr(SemaRef, 643 Id.TemplateId->getTemplateArgs(), 644 Id.TemplateId->NumArgs); 645 SemaRef.translateTemplateArguments(TemplateArgsPtr, Buffer); 646 TemplateArgsPtr.release(); 647 648 TemplateName TName = 649 Sema::TemplateTy::make(Id.TemplateId->Template).getAsVal<TemplateName>(); 650 651 Name = SemaRef.Context.getNameForTemplate(TName); 652 NameLoc = Id.TemplateId->TemplateNameLoc; 653 TemplateArgs = &Buffer; 654 } else { 655 Name = SemaRef.GetNameFromUnqualifiedId(Id); 656 NameLoc = Id.StartLocation; 657 TemplateArgs = 0; 658 } 659} 660 661/// Decompose the given template name into a list of lookup results. 662/// 663/// The unqualified ID must name a non-dependent template, which can 664/// be more easily tested by checking whether DecomposeUnqualifiedId 665/// found template arguments. 666static void DecomposeTemplateName(LookupResult &R, const UnqualifiedId &Id) { 667 assert(Id.getKind() == UnqualifiedId::IK_TemplateId); 668 TemplateName TName = 669 Sema::TemplateTy::make(Id.TemplateId->Template).getAsVal<TemplateName>(); 670 671 if (TemplateDecl *TD = TName.getAsTemplateDecl()) 672 R.addDecl(TD); 673 else if (OverloadedTemplateStorage *OT = TName.getAsOverloadedTemplate()) 674 for (OverloadedTemplateStorage::iterator I = OT->begin(), E = OT->end(); 675 I != E; ++I) 676 R.addDecl(*I); 677 678 R.resolveKind(); 679} 680 681static bool IsFullyFormedScope(Sema &SemaRef, CXXRecordDecl *Record) { 682 for (CXXRecordDecl::base_class_iterator I = Record->bases_begin(), 683 E = Record->bases_end(); I != E; ++I) { 684 CanQualType BaseT = SemaRef.Context.getCanonicalType((*I).getType()); 685 CanQual<RecordType> BaseRT = BaseT->getAs<RecordType>(); 686 if (!BaseRT) return false; 687 688 CXXRecordDecl *BaseRecord = cast<CXXRecordDecl>(BaseRT->getDecl()); 689 if (!BaseRecord->isDefinition() || 690 !IsFullyFormedScope(SemaRef, BaseRecord)) 691 return false; 692 } 693 694 return true; 695} 696 697/// Determines whether we can lookup this id-expression now or whether 698/// we have to wait until template instantiation is complete. 699static bool IsDependentIdExpression(Sema &SemaRef, const CXXScopeSpec &SS) { 700 DeclContext *DC = SemaRef.computeDeclContext(SS, false); 701 702 // If the qualifier scope isn't computable, it's definitely dependent. 703 if (!DC) return true; 704 705 // If the qualifier scope doesn't name a record, we can always look into it. 706 if (!isa<CXXRecordDecl>(DC)) return false; 707 708 // We can't look into record types unless they're fully-formed. 709 if (!IsFullyFormedScope(SemaRef, cast<CXXRecordDecl>(DC))) return true; 710 711 return false; 712} 713 714/// Determines if the given class is provably not derived from all of 715/// the prospective base classes. 716static bool IsProvablyNotDerivedFrom(Sema &SemaRef, 717 CXXRecordDecl *Record, 718 const llvm::SmallPtrSet<CXXRecordDecl*, 4> &Bases) { 719 if (Bases.count(Record->getCanonicalDecl())) 720 return false; 721 722 RecordDecl *RD = Record->getDefinition(SemaRef.Context); 723 if (!RD) return false; 724 Record = cast<CXXRecordDecl>(RD); 725 726 for (CXXRecordDecl::base_class_iterator I = Record->bases_begin(), 727 E = Record->bases_end(); I != E; ++I) { 728 CanQualType BaseT = SemaRef.Context.getCanonicalType((*I).getType()); 729 CanQual<RecordType> BaseRT = BaseT->getAs<RecordType>(); 730 if (!BaseRT) return false; 731 732 CXXRecordDecl *BaseRecord = cast<CXXRecordDecl>(BaseRT->getDecl()); 733 if (!IsProvablyNotDerivedFrom(SemaRef, BaseRecord, Bases)) 734 return false; 735 } 736 737 return true; 738} 739 740/// Determines if this is an instance member of a class. 741static bool IsInstanceMember(NamedDecl *D) { 742 assert(D->isCXXClassMember() && 743 "checking whether non-member is instance member"); 744 745 if (isa<FieldDecl>(D)) return true; 746 747 if (isa<CXXMethodDecl>(D)) 748 return !cast<CXXMethodDecl>(D)->isStatic(); 749 750 if (isa<FunctionTemplateDecl>(D)) { 751 D = cast<FunctionTemplateDecl>(D)->getTemplatedDecl(); 752 return !cast<CXXMethodDecl>(D)->isStatic(); 753 } 754 755 return false; 756} 757 758enum IMAKind { 759 /// The reference is definitely not an instance member access. 760 IMA_Static, 761 762 /// The reference may be an implicit instance member access. 763 IMA_Mixed, 764 765 /// The reference may be to an instance member, but it is invalid if 766 /// so, because the context is not an instance method. 767 IMA_Mixed_StaticContext, 768 769 /// The reference may be to an instance member, but it is invalid if 770 /// so, because the context is from an unrelated class. 771 IMA_Mixed_Unrelated, 772 773 /// The reference is definitely an implicit instance member access. 774 IMA_Instance, 775 776 /// The reference may be to an unresolved using declaration. 777 IMA_Unresolved, 778 779 /// The reference may be to an unresolved using declaration and the 780 /// context is not an instance method. 781 IMA_Unresolved_StaticContext, 782 783 /// The reference is to a member of an anonymous structure in a 784 /// non-class context. 785 IMA_AnonymousMember, 786 787 /// All possible referrents are instance members and the current 788 /// context is not an instance method. 789 IMA_Error_StaticContext, 790 791 /// All possible referrents are instance members of an unrelated 792 /// class. 793 IMA_Error_Unrelated 794}; 795 796/// The given lookup names class member(s) and is not being used for 797/// an address-of-member expression. Classify the type of access 798/// according to whether it's possible that this reference names an 799/// instance member. This is best-effort; it is okay to 800/// conservatively answer "yes", in which case some errors will simply 801/// not be caught until template-instantiation. 802static IMAKind ClassifyImplicitMemberAccess(Sema &SemaRef, 803 const LookupResult &R) { 804 assert(!R.empty() && (*R.begin())->isCXXClassMember()); 805 806 bool isStaticContext = 807 (!isa<CXXMethodDecl>(SemaRef.CurContext) || 808 cast<CXXMethodDecl>(SemaRef.CurContext)->isStatic()); 809 810 if (R.isUnresolvableResult()) 811 return isStaticContext ? IMA_Unresolved_StaticContext : IMA_Unresolved; 812 813 // Collect all the declaring classes of instance members we find. 814 bool hasNonInstance = false; 815 llvm::SmallPtrSet<CXXRecordDecl*, 4> Classes; 816 for (LookupResult::iterator I = R.begin(), E = R.end(); I != E; ++I) { 817 NamedDecl *D = (*I)->getUnderlyingDecl(); 818 if (IsInstanceMember(D)) { 819 CXXRecordDecl *R = cast<CXXRecordDecl>(D->getDeclContext()); 820 821 // If this is a member of an anonymous record, move out to the 822 // innermost non-anonymous struct or union. If there isn't one, 823 // that's a special case. 824 while (R->isAnonymousStructOrUnion()) { 825 R = dyn_cast<CXXRecordDecl>(R->getParent()); 826 if (!R) return IMA_AnonymousMember; 827 } 828 Classes.insert(R->getCanonicalDecl()); 829 } 830 else 831 hasNonInstance = true; 832 } 833 834 // If we didn't find any instance members, it can't be an implicit 835 // member reference. 836 if (Classes.empty()) 837 return IMA_Static; 838 839 // If the current context is not an instance method, it can't be 840 // an implicit member reference. 841 if (isStaticContext) 842 return (hasNonInstance ? IMA_Mixed_StaticContext : IMA_Error_StaticContext); 843 844 // If we can prove that the current context is unrelated to all the 845 // declaring classes, it can't be an implicit member reference (in 846 // which case it's an error if any of those members are selected). 847 if (IsProvablyNotDerivedFrom(SemaRef, 848 cast<CXXMethodDecl>(SemaRef.CurContext)->getParent(), 849 Classes)) 850 return (hasNonInstance ? IMA_Mixed_Unrelated : IMA_Error_Unrelated); 851 852 return (hasNonInstance ? IMA_Mixed : IMA_Instance); 853} 854 855/// Diagnose a reference to a field with no object available. 856static void DiagnoseInstanceReference(Sema &SemaRef, 857 const CXXScopeSpec &SS, 858 const LookupResult &R) { 859 SourceLocation Loc = R.getNameLoc(); 860 SourceRange Range(Loc); 861 if (SS.isSet()) Range.setBegin(SS.getRange().getBegin()); 862 863 if (R.getAsSingle<FieldDecl>()) { 864 if (CXXMethodDecl *MD = dyn_cast<CXXMethodDecl>(SemaRef.CurContext)) { 865 if (MD->isStatic()) { 866 // "invalid use of member 'x' in static member function" 867 SemaRef.Diag(Loc, diag::err_invalid_member_use_in_static_method) 868 << Range << R.getLookupName(); 869 return; 870 } 871 } 872 873 SemaRef.Diag(Loc, diag::err_invalid_non_static_member_use) 874 << R.getLookupName() << Range; 875 return; 876 } 877 878 SemaRef.Diag(Loc, diag::err_member_call_without_object) << Range; 879} 880 881/// Diagnose an empty lookup. 882/// 883/// \return false if new lookup candidates were found 884bool Sema::DiagnoseEmptyLookup(Scope *S, const CXXScopeSpec &SS, 885 LookupResult &R) { 886 DeclarationName Name = R.getLookupName(); 887 888 unsigned diagnostic = diag::err_undeclared_var_use; 889 unsigned diagnostic_suggest = diag::err_undeclared_var_use_suggest; 890 if (Name.getNameKind() == DeclarationName::CXXOperatorName || 891 Name.getNameKind() == DeclarationName::CXXLiteralOperatorName || 892 Name.getNameKind() == DeclarationName::CXXConversionFunctionName) { 893 diagnostic = diag::err_undeclared_use; 894 diagnostic_suggest = diag::err_undeclared_use_suggest; 895 } 896 897 // If the original lookup was an unqualified lookup, fake an 898 // unqualified lookup. This is useful when (for example) the 899 // original lookup would not have found something because it was a 900 // dependent name. 901 for (DeclContext *DC = SS.isEmpty()? CurContext : 0; 902 DC; DC = DC->getParent()) { 903 if (isa<CXXRecordDecl>(DC)) { 904 LookupQualifiedName(R, DC); 905 906 if (!R.empty()) { 907 // Don't give errors about ambiguities in this lookup. 908 R.suppressDiagnostics(); 909 910 CXXMethodDecl *CurMethod = dyn_cast<CXXMethodDecl>(CurContext); 911 bool isInstance = CurMethod && 912 CurMethod->isInstance() && 913 DC == CurMethod->getParent(); 914 915 // Give a code modification hint to insert 'this->'. 916 // TODO: fixit for inserting 'Base<T>::' in the other cases. 917 // Actually quite difficult! 918 if (isInstance) 919 Diag(R.getNameLoc(), diagnostic) << Name 920 << CodeModificationHint::CreateInsertion(R.getNameLoc(), 921 "this->"); 922 else 923 Diag(R.getNameLoc(), diagnostic) << Name; 924 925 // Do we really want to note all of these? 926 for (LookupResult::iterator I = R.begin(), E = R.end(); I != E; ++I) 927 Diag((*I)->getLocation(), diag::note_dependent_var_use); 928 929 // Tell the callee to try to recover. 930 return false; 931 } 932 } 933 } 934 935 // We didn't find anything, so try to correct for a typo. 936 if (S && CorrectTypo(R, S, &SS)) { 937 if (isa<ValueDecl>(*R.begin()) || isa<FunctionTemplateDecl>(*R.begin())) { 938 if (SS.isEmpty()) 939 Diag(R.getNameLoc(), diagnostic_suggest) << Name << R.getLookupName() 940 << CodeModificationHint::CreateReplacement(R.getNameLoc(), 941 R.getLookupName().getAsString()); 942 else 943 Diag(R.getNameLoc(), diag::err_no_member_suggest) 944 << Name << computeDeclContext(SS, false) << R.getLookupName() 945 << SS.getRange() 946 << CodeModificationHint::CreateReplacement(R.getNameLoc(), 947 R.getLookupName().getAsString()); 948 if (NamedDecl *ND = R.getAsSingle<NamedDecl>()) 949 Diag(ND->getLocation(), diag::note_previous_decl) 950 << ND->getDeclName(); 951 952 // Tell the callee to try to recover. 953 return false; 954 } 955 956 if (isa<TypeDecl>(*R.begin()) || isa<ObjCInterfaceDecl>(*R.begin())) { 957 // FIXME: If we ended up with a typo for a type name or 958 // Objective-C class name, we're in trouble because the parser 959 // is in the wrong place to recover. Suggest the typo 960 // correction, but don't make it a fix-it since we're not going 961 // to recover well anyway. 962 if (SS.isEmpty()) 963 Diag(R.getNameLoc(), diagnostic_suggest) << Name << R.getLookupName(); 964 else 965 Diag(R.getNameLoc(), diag::err_no_member_suggest) 966 << Name << computeDeclContext(SS, false) << R.getLookupName() 967 << SS.getRange(); 968 969 // Don't try to recover; it won't work. 970 return true; 971 } 972 973 R.clear(); 974 } 975 976 // Emit a special diagnostic for failed member lookups. 977 // FIXME: computing the declaration context might fail here (?) 978 if (!SS.isEmpty()) { 979 Diag(R.getNameLoc(), diag::err_no_member) 980 << Name << computeDeclContext(SS, false) 981 << SS.getRange(); 982 return true; 983 } 984 985 // Give up, we can't recover. 986 Diag(R.getNameLoc(), diagnostic) << Name; 987 return true; 988} 989 990Sema::OwningExprResult Sema::ActOnIdExpression(Scope *S, 991 const CXXScopeSpec &SS, 992 UnqualifiedId &Id, 993 bool HasTrailingLParen, 994 bool isAddressOfOperand) { 995 assert(!(isAddressOfOperand && HasTrailingLParen) && 996 "cannot be direct & operand and have a trailing lparen"); 997 998 if (SS.isInvalid()) 999 return ExprError(); 1000 1001 TemplateArgumentListInfo TemplateArgsBuffer; 1002 1003 // Decompose the UnqualifiedId into the following data. 1004 DeclarationName Name; 1005 SourceLocation NameLoc; 1006 const TemplateArgumentListInfo *TemplateArgs; 1007 DecomposeUnqualifiedId(*this, Id, TemplateArgsBuffer, 1008 Name, NameLoc, TemplateArgs); 1009 1010 IdentifierInfo *II = Name.getAsIdentifierInfo(); 1011 1012 // C++ [temp.dep.expr]p3: 1013 // An id-expression is type-dependent if it contains: 1014 // -- an identifier that was declared with a dependent type, 1015 // (note: handled after lookup) 1016 // -- a template-id that is dependent, 1017 // (note: handled in BuildTemplateIdExpr) 1018 // -- a conversion-function-id that specifies a dependent type, 1019 // -- a nested-name-specifier that contains a class-name that 1020 // names a dependent type. 1021 // Determine whether this is a member of an unknown specialization; 1022 // we need to handle these differently. 1023 if ((Name.getNameKind() == DeclarationName::CXXConversionFunctionName && 1024 Name.getCXXNameType()->isDependentType()) || 1025 (SS.isSet() && IsDependentIdExpression(*this, SS))) { 1026 return ActOnDependentIdExpression(SS, Name, NameLoc, 1027 isAddressOfOperand, 1028 TemplateArgs); 1029 } 1030 1031 // Perform the required lookup. 1032 LookupResult R(*this, Name, NameLoc, LookupOrdinaryName); 1033 if (TemplateArgs) { 1034 // Just re-use the lookup done by isTemplateName. 1035 DecomposeTemplateName(R, Id); 1036 } else { 1037 bool IvarLookupFollowUp = (!SS.isSet() && II && getCurMethodDecl()); 1038 LookupParsedName(R, S, &SS, !IvarLookupFollowUp); 1039 1040 // If this reference is in an Objective-C method, then we need to do 1041 // some special Objective-C lookup, too. 1042 if (IvarLookupFollowUp) { 1043 OwningExprResult E(LookupInObjCMethod(R, S, II, true)); 1044 if (E.isInvalid()) 1045 return ExprError(); 1046 1047 Expr *Ex = E.takeAs<Expr>(); 1048 if (Ex) return Owned(Ex); 1049 } 1050 } 1051 1052 if (R.isAmbiguous()) 1053 return ExprError(); 1054 1055 // Determine whether this name might be a candidate for 1056 // argument-dependent lookup. 1057 bool ADL = UseArgumentDependentLookup(SS, R, HasTrailingLParen); 1058 1059 if (R.empty() && !ADL) { 1060 // Otherwise, this could be an implicitly declared function reference (legal 1061 // in C90, extension in C99, forbidden in C++). 1062 if (HasTrailingLParen && II && !getLangOptions().CPlusPlus) { 1063 NamedDecl *D = ImplicitlyDefineFunction(NameLoc, *II, S); 1064 if (D) R.addDecl(D); 1065 } 1066 1067 // If this name wasn't predeclared and if this is not a function 1068 // call, diagnose the problem. 1069 if (R.empty()) { 1070 if (DiagnoseEmptyLookup(S, SS, R)) 1071 return ExprError(); 1072 1073 assert(!R.empty() && 1074 "DiagnoseEmptyLookup returned false but added no results"); 1075 1076 // If we found an Objective-C instance variable, let 1077 // LookupInObjCMethod build the appropriate expression to 1078 // reference the ivar. 1079 if (ObjCIvarDecl *Ivar = R.getAsSingle<ObjCIvarDecl>()) { 1080 R.clear(); 1081 OwningExprResult E(LookupInObjCMethod(R, S, Ivar->getIdentifier())); 1082 assert(E.isInvalid() || E.get()); 1083 return move(E); 1084 } 1085 } 1086 } 1087 1088 // This is guaranteed from this point on. 1089 assert(!R.empty() || ADL); 1090 1091 if (VarDecl *Var = R.getAsSingle<VarDecl>()) { 1092 // Warn about constructs like: 1093 // if (void *X = foo()) { ... } else { X }. 1094 // In the else block, the pointer is always false. 1095 1096 if (Var->isDeclaredInCondition() && Var->getType()->isScalarType()) { 1097 Scope *CheckS = S; 1098 while (CheckS && CheckS->getControlParent()) { 1099 if (CheckS->isWithinElse() && 1100 CheckS->getControlParent()->isDeclScope(DeclPtrTy::make(Var))) { 1101 ExprError(Diag(NameLoc, diag::warn_value_always_zero) 1102 << Var->getDeclName() 1103 << (Var->getType()->isPointerType()? 2 : 1104 Var->getType()->isBooleanType()? 1 : 0)); 1105 break; 1106 } 1107 1108 // Move to the parent of this scope. 1109 CheckS = CheckS->getParent(); 1110 } 1111 } 1112 } else if (FunctionDecl *Func = R.getAsSingle<FunctionDecl>()) { 1113 if (!getLangOptions().CPlusPlus && !Func->hasPrototype()) { 1114 // C99 DR 316 says that, if a function type comes from a 1115 // function definition (without a prototype), that type is only 1116 // used for checking compatibility. Therefore, when referencing 1117 // the function, we pretend that we don't have the full function 1118 // type. 1119 if (DiagnoseUseOfDecl(Func, NameLoc)) 1120 return ExprError(); 1121 1122 QualType T = Func->getType(); 1123 QualType NoProtoType = T; 1124 if (const FunctionProtoType *Proto = T->getAs<FunctionProtoType>()) 1125 NoProtoType = Context.getFunctionNoProtoType(Proto->getResultType()); 1126 return BuildDeclRefExpr(Func, NoProtoType, NameLoc, &SS); 1127 } 1128 } 1129 1130 // Check whether this might be a C++ implicit instance member access. 1131 // C++ [expr.prim.general]p6: 1132 // Within the definition of a non-static member function, an 1133 // identifier that names a non-static member is transformed to a 1134 // class member access expression. 1135 // But note that &SomeClass::foo is grammatically distinct, even 1136 // though we don't parse it that way. 1137 if (!R.empty() && (*R.begin())->isCXXClassMember()) { 1138 bool isAbstractMemberPointer = (isAddressOfOperand && !SS.isEmpty()); 1139 if (!isAbstractMemberPointer) 1140 return BuildPossibleImplicitMemberExpr(SS, R, TemplateArgs); 1141 } 1142 1143 if (TemplateArgs) 1144 return BuildTemplateIdExpr(SS, R, ADL, *TemplateArgs); 1145 1146 return BuildDeclarationNameExpr(SS, R, ADL); 1147} 1148 1149/// Builds an expression which might be an implicit member expression. 1150Sema::OwningExprResult 1151Sema::BuildPossibleImplicitMemberExpr(const CXXScopeSpec &SS, 1152 LookupResult &R, 1153 const TemplateArgumentListInfo *TemplateArgs) { 1154 switch (ClassifyImplicitMemberAccess(*this, R)) { 1155 case IMA_Instance: 1156 return BuildImplicitMemberExpr(SS, R, TemplateArgs, true); 1157 1158 case IMA_AnonymousMember: 1159 assert(R.isSingleResult()); 1160 return BuildAnonymousStructUnionMemberReference(R.getNameLoc(), 1161 R.getAsSingle<FieldDecl>()); 1162 1163 case IMA_Mixed: 1164 case IMA_Mixed_Unrelated: 1165 case IMA_Unresolved: 1166 return BuildImplicitMemberExpr(SS, R, TemplateArgs, false); 1167 1168 case IMA_Static: 1169 case IMA_Mixed_StaticContext: 1170 case IMA_Unresolved_StaticContext: 1171 if (TemplateArgs) 1172 return BuildTemplateIdExpr(SS, R, false, *TemplateArgs); 1173 return BuildDeclarationNameExpr(SS, R, false); 1174 1175 case IMA_Error_StaticContext: 1176 case IMA_Error_Unrelated: 1177 DiagnoseInstanceReference(*this, SS, R); 1178 return ExprError(); 1179 } 1180 1181 llvm_unreachable("unexpected instance member access kind"); 1182 return ExprError(); 1183} 1184 1185/// BuildQualifiedDeclarationNameExpr - Build a C++ qualified 1186/// declaration name, generally during template instantiation. 1187/// There's a large number of things which don't need to be done along 1188/// this path. 1189Sema::OwningExprResult 1190Sema::BuildQualifiedDeclarationNameExpr(const CXXScopeSpec &SS, 1191 DeclarationName Name, 1192 SourceLocation NameLoc) { 1193 DeclContext *DC; 1194 if (!(DC = computeDeclContext(SS, false)) || 1195 DC->isDependentContext() || 1196 RequireCompleteDeclContext(SS)) 1197 return BuildDependentDeclRefExpr(SS, Name, NameLoc, 0); 1198 1199 LookupResult R(*this, Name, NameLoc, LookupOrdinaryName); 1200 LookupQualifiedName(R, DC); 1201 1202 if (R.isAmbiguous()) 1203 return ExprError(); 1204 1205 if (R.empty()) { 1206 Diag(NameLoc, diag::err_no_member) << Name << DC << SS.getRange(); 1207 return ExprError(); 1208 } 1209 1210 return BuildDeclarationNameExpr(SS, R, /*ADL*/ false); 1211} 1212 1213/// LookupInObjCMethod - The parser has read a name in, and Sema has 1214/// detected that we're currently inside an ObjC method. Perform some 1215/// additional lookup. 1216/// 1217/// Ideally, most of this would be done by lookup, but there's 1218/// actually quite a lot of extra work involved. 1219/// 1220/// Returns a null sentinel to indicate trivial success. 1221Sema::OwningExprResult 1222Sema::LookupInObjCMethod(LookupResult &Lookup, Scope *S, 1223 IdentifierInfo *II, 1224 bool AllowBuiltinCreation) { 1225 SourceLocation Loc = Lookup.getNameLoc(); 1226 1227 // There are two cases to handle here. 1) scoped lookup could have failed, 1228 // in which case we should look for an ivar. 2) scoped lookup could have 1229 // found a decl, but that decl is outside the current instance method (i.e. 1230 // a global variable). In these two cases, we do a lookup for an ivar with 1231 // this name, if the lookup sucedes, we replace it our current decl. 1232 1233 // If we're in a class method, we don't normally want to look for 1234 // ivars. But if we don't find anything else, and there's an 1235 // ivar, that's an error. 1236 bool IsClassMethod = getCurMethodDecl()->isClassMethod(); 1237 1238 bool LookForIvars; 1239 if (Lookup.empty()) 1240 LookForIvars = true; 1241 else if (IsClassMethod) 1242 LookForIvars = false; 1243 else 1244 LookForIvars = (Lookup.isSingleResult() && 1245 Lookup.getFoundDecl()->isDefinedOutsideFunctionOrMethod()); 1246 1247 if (LookForIvars) { 1248 ObjCInterfaceDecl *IFace = getCurMethodDecl()->getClassInterface(); 1249 ObjCInterfaceDecl *ClassDeclared; 1250 if (ObjCIvarDecl *IV = IFace->lookupInstanceVariable(II, ClassDeclared)) { 1251 // Diagnose using an ivar in a class method. 1252 if (IsClassMethod) 1253 return ExprError(Diag(Loc, diag::error_ivar_use_in_class_method) 1254 << IV->getDeclName()); 1255 1256 // If we're referencing an invalid decl, just return this as a silent 1257 // error node. The error diagnostic was already emitted on the decl. 1258 if (IV->isInvalidDecl()) 1259 return ExprError(); 1260 1261 // Check if referencing a field with __attribute__((deprecated)). 1262 if (DiagnoseUseOfDecl(IV, Loc)) 1263 return ExprError(); 1264 1265 // Diagnose the use of an ivar outside of the declaring class. 1266 if (IV->getAccessControl() == ObjCIvarDecl::Private && 1267 ClassDeclared != IFace) 1268 Diag(Loc, diag::error_private_ivar_access) << IV->getDeclName(); 1269 1270 // FIXME: This should use a new expr for a direct reference, don't 1271 // turn this into Self->ivar, just return a BareIVarExpr or something. 1272 IdentifierInfo &II = Context.Idents.get("self"); 1273 UnqualifiedId SelfName; 1274 SelfName.setIdentifier(&II, SourceLocation()); 1275 CXXScopeSpec SelfScopeSpec; 1276 OwningExprResult SelfExpr = ActOnIdExpression(S, SelfScopeSpec, 1277 SelfName, false, false); 1278 MarkDeclarationReferenced(Loc, IV); 1279 return Owned(new (Context) 1280 ObjCIvarRefExpr(IV, IV->getType(), Loc, 1281 SelfExpr.takeAs<Expr>(), true, true)); 1282 } 1283 } else if (getCurMethodDecl()->isInstanceMethod()) { 1284 // We should warn if a local variable hides an ivar. 1285 ObjCInterfaceDecl *IFace = getCurMethodDecl()->getClassInterface(); 1286 ObjCInterfaceDecl *ClassDeclared; 1287 if (ObjCIvarDecl *IV = IFace->lookupInstanceVariable(II, ClassDeclared)) { 1288 if (IV->getAccessControl() != ObjCIvarDecl::Private || 1289 IFace == ClassDeclared) 1290 Diag(Loc, diag::warn_ivar_use_hidden) << IV->getDeclName(); 1291 } 1292 } 1293 1294 // Needed to implement property "super.method" notation. 1295 if (Lookup.empty() && II->isStr("super")) { 1296 QualType T; 1297 1298 if (getCurMethodDecl()->isInstanceMethod()) 1299 T = Context.getObjCObjectPointerType(Context.getObjCInterfaceType( 1300 getCurMethodDecl()->getClassInterface())); 1301 else 1302 T = Context.getObjCClassType(); 1303 return Owned(new (Context) ObjCSuperExpr(Loc, T)); 1304 } 1305 if (Lookup.empty() && II && AllowBuiltinCreation) { 1306 // FIXME. Consolidate this with similar code in LookupName. 1307 if (unsigned BuiltinID = II->getBuiltinID()) { 1308 if (!(getLangOptions().CPlusPlus && 1309 Context.BuiltinInfo.isPredefinedLibFunction(BuiltinID))) { 1310 NamedDecl *D = LazilyCreateBuiltin((IdentifierInfo *)II, BuiltinID, 1311 S, Lookup.isForRedeclaration(), 1312 Lookup.getNameLoc()); 1313 if (D) Lookup.addDecl(D); 1314 } 1315 } 1316 } 1317 // Sentinel value saying that we didn't do anything special. 1318 return Owned((Expr*) 0); 1319} 1320 1321/// \brief Cast member's object to its own class if necessary. 1322bool 1323Sema::PerformObjectMemberConversion(Expr *&From, NamedDecl *Member) { 1324 if (FieldDecl *FD = dyn_cast<FieldDecl>(Member)) 1325 if (CXXRecordDecl *RD = 1326 dyn_cast<CXXRecordDecl>(FD->getDeclContext())) { 1327 QualType DestType = 1328 Context.getCanonicalType(Context.getTypeDeclType(RD)); 1329 if (DestType->isDependentType() || From->getType()->isDependentType()) 1330 return false; 1331 QualType FromRecordType = From->getType(); 1332 QualType DestRecordType = DestType; 1333 if (FromRecordType->getAs<PointerType>()) { 1334 DestType = Context.getPointerType(DestType); 1335 FromRecordType = FromRecordType->getPointeeType(); 1336 } 1337 if (!Context.hasSameUnqualifiedType(FromRecordType, DestRecordType) && 1338 CheckDerivedToBaseConversion(FromRecordType, 1339 DestRecordType, 1340 From->getSourceRange().getBegin(), 1341 From->getSourceRange())) 1342 return true; 1343 ImpCastExprToType(From, DestType, CastExpr::CK_DerivedToBase, 1344 /*isLvalue=*/true); 1345 } 1346 return false; 1347} 1348 1349/// \brief Build a MemberExpr AST node. 1350static MemberExpr *BuildMemberExpr(ASTContext &C, Expr *Base, bool isArrow, 1351 const CXXScopeSpec &SS, ValueDecl *Member, 1352 SourceLocation Loc, QualType Ty, 1353 const TemplateArgumentListInfo *TemplateArgs = 0) { 1354 NestedNameSpecifier *Qualifier = 0; 1355 SourceRange QualifierRange; 1356 if (SS.isSet()) { 1357 Qualifier = (NestedNameSpecifier *) SS.getScopeRep(); 1358 QualifierRange = SS.getRange(); 1359 } 1360 1361 return MemberExpr::Create(C, Base, isArrow, Qualifier, QualifierRange, 1362 Member, Loc, TemplateArgs, Ty); 1363} 1364 1365/// Builds an implicit member access expression. The current context 1366/// is known to be an instance method, and the given unqualified lookup 1367/// set is known to contain only instance members, at least one of which 1368/// is from an appropriate type. 1369Sema::OwningExprResult 1370Sema::BuildImplicitMemberExpr(const CXXScopeSpec &SS, 1371 LookupResult &R, 1372 const TemplateArgumentListInfo *TemplateArgs, 1373 bool IsKnownInstance) { 1374 assert(!R.empty() && !R.isAmbiguous()); 1375 1376 SourceLocation Loc = R.getNameLoc(); 1377 1378 // We may have found a field within an anonymous union or struct 1379 // (C++ [class.union]). 1380 // FIXME: This needs to happen post-isImplicitMemberReference? 1381 // FIXME: template-ids inside anonymous structs? 1382 if (FieldDecl *FD = R.getAsSingle<FieldDecl>()) 1383 if (cast<RecordDecl>(FD->getDeclContext())->isAnonymousStructOrUnion()) 1384 return BuildAnonymousStructUnionMemberReference(Loc, FD); 1385 1386 // If this is known to be an instance access, go ahead and build a 1387 // 'this' expression now. 1388 QualType ThisType = cast<CXXMethodDecl>(CurContext)->getThisType(Context); 1389 Expr *This = 0; // null signifies implicit access 1390 if (IsKnownInstance) { 1391 SourceLocation Loc = R.getNameLoc(); 1392 if (SS.getRange().isValid()) 1393 Loc = SS.getRange().getBegin(); 1394 This = new (Context) CXXThisExpr(Loc, ThisType, /*isImplicit=*/true); 1395 } 1396 1397 return BuildMemberReferenceExpr(ExprArg(*this, This), ThisType, 1398 /*OpLoc*/ SourceLocation(), 1399 /*IsArrow*/ true, 1400 SS, 1401 /*FirstQualifierInScope*/ 0, 1402 R, TemplateArgs); 1403} 1404 1405bool Sema::UseArgumentDependentLookup(const CXXScopeSpec &SS, 1406 const LookupResult &R, 1407 bool HasTrailingLParen) { 1408 // Only when used directly as the postfix-expression of a call. 1409 if (!HasTrailingLParen) 1410 return false; 1411 1412 // Never if a scope specifier was provided. 1413 if (SS.isSet()) 1414 return false; 1415 1416 // Only in C++ or ObjC++. 1417 if (!getLangOptions().CPlusPlus) 1418 return false; 1419 1420 // Turn off ADL when we find certain kinds of declarations during 1421 // normal lookup: 1422 for (LookupResult::iterator I = R.begin(), E = R.end(); I != E; ++I) { 1423 NamedDecl *D = *I; 1424 1425 // C++0x [basic.lookup.argdep]p3: 1426 // -- a declaration of a class member 1427 // Since using decls preserve this property, we check this on the 1428 // original decl. 1429 if (D->isCXXClassMember()) 1430 return false; 1431 1432 // C++0x [basic.lookup.argdep]p3: 1433 // -- a block-scope function declaration that is not a 1434 // using-declaration 1435 // NOTE: we also trigger this for function templates (in fact, we 1436 // don't check the decl type at all, since all other decl types 1437 // turn off ADL anyway). 1438 if (isa<UsingShadowDecl>(D)) 1439 D = cast<UsingShadowDecl>(D)->getTargetDecl(); 1440 else if (D->getDeclContext()->isFunctionOrMethod()) 1441 return false; 1442 1443 // C++0x [basic.lookup.argdep]p3: 1444 // -- a declaration that is neither a function or a function 1445 // template 1446 // And also for builtin functions. 1447 if (isa<FunctionDecl>(D)) { 1448 FunctionDecl *FDecl = cast<FunctionDecl>(D); 1449 1450 // But also builtin functions. 1451 if (FDecl->getBuiltinID() && FDecl->isImplicit()) 1452 return false; 1453 } else if (!isa<FunctionTemplateDecl>(D)) 1454 return false; 1455 } 1456 1457 return true; 1458} 1459 1460 1461/// Diagnoses obvious problems with the use of the given declaration 1462/// as an expression. This is only actually called for lookups that 1463/// were not overloaded, and it doesn't promise that the declaration 1464/// will in fact be used. 1465static bool CheckDeclInExpr(Sema &S, SourceLocation Loc, NamedDecl *D) { 1466 if (isa<TypedefDecl>(D)) { 1467 S.Diag(Loc, diag::err_unexpected_typedef) << D->getDeclName(); 1468 return true; 1469 } 1470 1471 if (isa<ObjCInterfaceDecl>(D)) { 1472 S.Diag(Loc, diag::err_unexpected_interface) << D->getDeclName(); 1473 return true; 1474 } 1475 1476 if (isa<NamespaceDecl>(D)) { 1477 S.Diag(Loc, diag::err_unexpected_namespace) << D->getDeclName(); 1478 return true; 1479 } 1480 1481 return false; 1482} 1483 1484Sema::OwningExprResult 1485Sema::BuildDeclarationNameExpr(const CXXScopeSpec &SS, 1486 LookupResult &R, 1487 bool NeedsADL) { 1488 // If this is a single, fully-resolved result and we don't need ADL, 1489 // just build an ordinary singleton decl ref. 1490 if (!NeedsADL && R.isSingleResult()) 1491 return BuildDeclarationNameExpr(SS, R.getNameLoc(), R.getFoundDecl()); 1492 1493 // We only need to check the declaration if there's exactly one 1494 // result, because in the overloaded case the results can only be 1495 // functions and function templates. 1496 if (R.isSingleResult() && 1497 CheckDeclInExpr(*this, R.getNameLoc(), R.getFoundDecl())) 1498 return ExprError(); 1499 1500 bool Dependent 1501 = UnresolvedLookupExpr::ComputeDependence(R.begin(), R.end(), 0); 1502 UnresolvedLookupExpr *ULE 1503 = UnresolvedLookupExpr::Create(Context, Dependent, 1504 (NestedNameSpecifier*) SS.getScopeRep(), 1505 SS.getRange(), 1506 R.getLookupName(), R.getNameLoc(), 1507 NeedsADL, R.isOverloadedResult()); 1508 for (LookupResult::iterator I = R.begin(), E = R.end(); I != E; ++I) 1509 ULE->addDecl(*I); 1510 1511 return Owned(ULE); 1512} 1513 1514 1515/// \brief Complete semantic analysis for a reference to the given declaration. 1516Sema::OwningExprResult 1517Sema::BuildDeclarationNameExpr(const CXXScopeSpec &SS, 1518 SourceLocation Loc, NamedDecl *D) { 1519 assert(D && "Cannot refer to a NULL declaration"); 1520 assert(!isa<FunctionTemplateDecl>(D) && 1521 "Cannot refer unambiguously to a function template"); 1522 1523 if (CheckDeclInExpr(*this, Loc, D)) 1524 return ExprError(); 1525 1526 if (TemplateDecl *Template = dyn_cast<TemplateDecl>(D)) { 1527 // Specifically diagnose references to class templates that are missing 1528 // a template argument list. 1529 Diag(Loc, diag::err_template_decl_ref) 1530 << Template << SS.getRange(); 1531 Diag(Template->getLocation(), diag::note_template_decl_here); 1532 return ExprError(); 1533 } 1534 1535 // Make sure that we're referring to a value. 1536 ValueDecl *VD = dyn_cast<ValueDecl>(D); 1537 if (!VD) { 1538 Diag(Loc, diag::err_ref_non_value) 1539 << D << SS.getRange(); 1540 Diag(D->getLocation(), diag::note_declared_at); 1541 return ExprError(); 1542 } 1543 1544 // Check whether this declaration can be used. Note that we suppress 1545 // this check when we're going to perform argument-dependent lookup 1546 // on this function name, because this might not be the function 1547 // that overload resolution actually selects. 1548 if (DiagnoseUseOfDecl(VD, Loc)) 1549 return ExprError(); 1550 1551 // Only create DeclRefExpr's for valid Decl's. 1552 if (VD->isInvalidDecl()) 1553 return ExprError(); 1554 1555 // If the identifier reference is inside a block, and it refers to a value 1556 // that is outside the block, create a BlockDeclRefExpr instead of a 1557 // DeclRefExpr. This ensures the value is treated as a copy-in snapshot when 1558 // the block is formed. 1559 // 1560 // We do not do this for things like enum constants, global variables, etc, 1561 // as they do not get snapshotted. 1562 // 1563 if (CurBlock && ShouldSnapshotBlockValueReference(CurBlock, VD)) { 1564 if (VD->getType().getTypePtr()->isVariablyModifiedType()) { 1565 Diag(Loc, diag::err_ref_vm_type); 1566 Diag(D->getLocation(), diag::note_declared_at); 1567 return ExprError(); 1568 } 1569 1570 if (VD->getType()->isArrayType()) { 1571 Diag(Loc, diag::err_ref_array_type); 1572 Diag(D->getLocation(), diag::note_declared_at); 1573 return ExprError(); 1574 } 1575 1576 MarkDeclarationReferenced(Loc, VD); 1577 QualType ExprTy = VD->getType().getNonReferenceType(); 1578 // The BlocksAttr indicates the variable is bound by-reference. 1579 if (VD->getAttr<BlocksAttr>()) 1580 return Owned(new (Context) BlockDeclRefExpr(VD, ExprTy, Loc, true)); 1581 // This is to record that a 'const' was actually synthesize and added. 1582 bool constAdded = !ExprTy.isConstQualified(); 1583 // Variable will be bound by-copy, make it const within the closure. 1584 1585 ExprTy.addConst(); 1586 return Owned(new (Context) BlockDeclRefExpr(VD, ExprTy, Loc, false, 1587 constAdded)); 1588 } 1589 // If this reference is not in a block or if the referenced variable is 1590 // within the block, create a normal DeclRefExpr. 1591 1592 return BuildDeclRefExpr(VD, VD->getType().getNonReferenceType(), Loc, &SS); 1593} 1594 1595Sema::OwningExprResult Sema::ActOnPredefinedExpr(SourceLocation Loc, 1596 tok::TokenKind Kind) { 1597 PredefinedExpr::IdentType IT; 1598 1599 switch (Kind) { 1600 default: assert(0 && "Unknown simple primary expr!"); 1601 case tok::kw___func__: IT = PredefinedExpr::Func; break; // [C99 6.4.2.2] 1602 case tok::kw___FUNCTION__: IT = PredefinedExpr::Function; break; 1603 case tok::kw___PRETTY_FUNCTION__: IT = PredefinedExpr::PrettyFunction; break; 1604 } 1605 1606 // Pre-defined identifiers are of type char[x], where x is the length of the 1607 // string. 1608 1609 Decl *currentDecl = getCurFunctionOrMethodDecl(); 1610 if (!currentDecl) { 1611 Diag(Loc, diag::ext_predef_outside_function); 1612 currentDecl = Context.getTranslationUnitDecl(); 1613 } 1614 1615 QualType ResTy; 1616 if (cast<DeclContext>(currentDecl)->isDependentContext()) { 1617 ResTy = Context.DependentTy; 1618 } else { 1619 unsigned Length = 1620 PredefinedExpr::ComputeName(Context, IT, currentDecl).length(); 1621 1622 llvm::APInt LengthI(32, Length + 1); 1623 ResTy = Context.CharTy.withConst(); 1624 ResTy = Context.getConstantArrayType(ResTy, LengthI, ArrayType::Normal, 0); 1625 } 1626 return Owned(new (Context) PredefinedExpr(Loc, ResTy, IT)); 1627} 1628 1629Sema::OwningExprResult Sema::ActOnCharacterConstant(const Token &Tok) { 1630 llvm::SmallString<16> CharBuffer; 1631 CharBuffer.resize(Tok.getLength()); 1632 const char *ThisTokBegin = &CharBuffer[0]; 1633 unsigned ActualLength = PP.getSpelling(Tok, ThisTokBegin); 1634 1635 CharLiteralParser Literal(ThisTokBegin, ThisTokBegin+ActualLength, 1636 Tok.getLocation(), PP); 1637 if (Literal.hadError()) 1638 return ExprError(); 1639 1640 QualType Ty; 1641 if (!getLangOptions().CPlusPlus) 1642 Ty = Context.IntTy; // 'x' and L'x' -> int in C. 1643 else if (Literal.isWide()) 1644 Ty = Context.WCharTy; // L'x' -> wchar_t in C++. 1645 else 1646 Ty = Context.CharTy; // 'x' -> char in C++ 1647 1648 return Owned(new (Context) CharacterLiteral(Literal.getValue(), 1649 Literal.isWide(), 1650 Ty, Tok.getLocation())); 1651} 1652 1653Action::OwningExprResult Sema::ActOnNumericConstant(const Token &Tok) { 1654 // Fast path for a single digit (which is quite common). A single digit 1655 // cannot have a trigraph, escaped newline, radix prefix, or type suffix. 1656 if (Tok.getLength() == 1) { 1657 const char Val = PP.getSpellingOfSingleCharacterNumericConstant(Tok); 1658 unsigned IntSize = Context.Target.getIntWidth(); 1659 return Owned(new (Context) IntegerLiteral(llvm::APInt(IntSize, Val-'0'), 1660 Context.IntTy, Tok.getLocation())); 1661 } 1662 1663 llvm::SmallString<512> IntegerBuffer; 1664 // Add padding so that NumericLiteralParser can overread by one character. 1665 IntegerBuffer.resize(Tok.getLength()+1); 1666 const char *ThisTokBegin = &IntegerBuffer[0]; 1667 1668 // Get the spelling of the token, which eliminates trigraphs, etc. 1669 unsigned ActualLength = PP.getSpelling(Tok, ThisTokBegin); 1670 1671 NumericLiteralParser Literal(ThisTokBegin, ThisTokBegin+ActualLength, 1672 Tok.getLocation(), PP); 1673 if (Literal.hadError) 1674 return ExprError(); 1675 1676 Expr *Res; 1677 1678 if (Literal.isFloatingLiteral()) { 1679 QualType Ty; 1680 if (Literal.isFloat) 1681 Ty = Context.FloatTy; 1682 else if (!Literal.isLong) 1683 Ty = Context.DoubleTy; 1684 else 1685 Ty = Context.LongDoubleTy; 1686 1687 const llvm::fltSemantics &Format = Context.getFloatTypeSemantics(Ty); 1688 1689 using llvm::APFloat; 1690 APFloat Val(Format); 1691 1692 APFloat::opStatus result = Literal.GetFloatValue(Val); 1693 1694 // Overflow is always an error, but underflow is only an error if 1695 // we underflowed to zero (APFloat reports denormals as underflow). 1696 if ((result & APFloat::opOverflow) || 1697 ((result & APFloat::opUnderflow) && Val.isZero())) { 1698 unsigned diagnostic; 1699 llvm::SmallVector<char, 20> buffer; 1700 if (result & APFloat::opOverflow) { 1701 diagnostic = diag::err_float_overflow; 1702 APFloat::getLargest(Format).toString(buffer); 1703 } else { 1704 diagnostic = diag::err_float_underflow; 1705 APFloat::getSmallest(Format).toString(buffer); 1706 } 1707 1708 Diag(Tok.getLocation(), diagnostic) 1709 << Ty 1710 << llvm::StringRef(buffer.data(), buffer.size()); 1711 } 1712 1713 bool isExact = (result == APFloat::opOK); 1714 Res = new (Context) FloatingLiteral(Val, isExact, Ty, Tok.getLocation()); 1715 1716 } else if (!Literal.isIntegerLiteral()) { 1717 return ExprError(); 1718 } else { 1719 QualType Ty; 1720 1721 // long long is a C99 feature. 1722 if (!getLangOptions().C99 && !getLangOptions().CPlusPlus0x && 1723 Literal.isLongLong) 1724 Diag(Tok.getLocation(), diag::ext_longlong); 1725 1726 // Get the value in the widest-possible width. 1727 llvm::APInt ResultVal(Context.Target.getIntMaxTWidth(), 0); 1728 1729 if (Literal.GetIntegerValue(ResultVal)) { 1730 // If this value didn't fit into uintmax_t, warn and force to ull. 1731 Diag(Tok.getLocation(), diag::warn_integer_too_large); 1732 Ty = Context.UnsignedLongLongTy; 1733 assert(Context.getTypeSize(Ty) == ResultVal.getBitWidth() && 1734 "long long is not intmax_t?"); 1735 } else { 1736 // If this value fits into a ULL, try to figure out what else it fits into 1737 // according to the rules of C99 6.4.4.1p5. 1738 1739 // Octal, Hexadecimal, and integers with a U suffix are allowed to 1740 // be an unsigned int. 1741 bool AllowUnsigned = Literal.isUnsigned || Literal.getRadix() != 10; 1742 1743 // Check from smallest to largest, picking the smallest type we can. 1744 unsigned Width = 0; 1745 if (!Literal.isLong && !Literal.isLongLong) { 1746 // Are int/unsigned possibilities? 1747 unsigned IntSize = Context.Target.getIntWidth(); 1748 1749 // Does it fit in a unsigned int? 1750 if (ResultVal.isIntN(IntSize)) { 1751 // Does it fit in a signed int? 1752 if (!Literal.isUnsigned && ResultVal[IntSize-1] == 0) 1753 Ty = Context.IntTy; 1754 else if (AllowUnsigned) 1755 Ty = Context.UnsignedIntTy; 1756 Width = IntSize; 1757 } 1758 } 1759 1760 // Are long/unsigned long possibilities? 1761 if (Ty.isNull() && !Literal.isLongLong) { 1762 unsigned LongSize = Context.Target.getLongWidth(); 1763 1764 // Does it fit in a unsigned long? 1765 if (ResultVal.isIntN(LongSize)) { 1766 // Does it fit in a signed long? 1767 if (!Literal.isUnsigned && ResultVal[LongSize-1] == 0) 1768 Ty = Context.LongTy; 1769 else if (AllowUnsigned) 1770 Ty = Context.UnsignedLongTy; 1771 Width = LongSize; 1772 } 1773 } 1774 1775 // Finally, check long long if needed. 1776 if (Ty.isNull()) { 1777 unsigned LongLongSize = Context.Target.getLongLongWidth(); 1778 1779 // Does it fit in a unsigned long long? 1780 if (ResultVal.isIntN(LongLongSize)) { 1781 // Does it fit in a signed long long? 1782 if (!Literal.isUnsigned && ResultVal[LongLongSize-1] == 0) 1783 Ty = Context.LongLongTy; 1784 else if (AllowUnsigned) 1785 Ty = Context.UnsignedLongLongTy; 1786 Width = LongLongSize; 1787 } 1788 } 1789 1790 // If we still couldn't decide a type, we probably have something that 1791 // does not fit in a signed long long, but has no U suffix. 1792 if (Ty.isNull()) { 1793 Diag(Tok.getLocation(), diag::warn_integer_too_large_for_signed); 1794 Ty = Context.UnsignedLongLongTy; 1795 Width = Context.Target.getLongLongWidth(); 1796 } 1797 1798 if (ResultVal.getBitWidth() != Width) 1799 ResultVal.trunc(Width); 1800 } 1801 Res = new (Context) IntegerLiteral(ResultVal, Ty, Tok.getLocation()); 1802 } 1803 1804 // If this is an imaginary literal, create the ImaginaryLiteral wrapper. 1805 if (Literal.isImaginary) 1806 Res = new (Context) ImaginaryLiteral(Res, 1807 Context.getComplexType(Res->getType())); 1808 1809 return Owned(Res); 1810} 1811 1812Action::OwningExprResult Sema::ActOnParenExpr(SourceLocation L, 1813 SourceLocation R, ExprArg Val) { 1814 Expr *E = Val.takeAs<Expr>(); 1815 assert((E != 0) && "ActOnParenExpr() missing expr"); 1816 return Owned(new (Context) ParenExpr(L, R, E)); 1817} 1818 1819/// The UsualUnaryConversions() function is *not* called by this routine. 1820/// See C99 6.3.2.1p[2-4] for more details. 1821bool Sema::CheckSizeOfAlignOfOperand(QualType exprType, 1822 SourceLocation OpLoc, 1823 const SourceRange &ExprRange, 1824 bool isSizeof) { 1825 if (exprType->isDependentType()) 1826 return false; 1827 1828 // C++ [expr.sizeof]p2: "When applied to a reference or a reference type, 1829 // the result is the size of the referenced type." 1830 // C++ [expr.alignof]p3: "When alignof is applied to a reference type, the 1831 // result shall be the alignment of the referenced type." 1832 if (const ReferenceType *Ref = exprType->getAs<ReferenceType>()) 1833 exprType = Ref->getPointeeType(); 1834 1835 // C99 6.5.3.4p1: 1836 if (exprType->isFunctionType()) { 1837 // alignof(function) is allowed as an extension. 1838 if (isSizeof) 1839 Diag(OpLoc, diag::ext_sizeof_function_type) << ExprRange; 1840 return false; 1841 } 1842 1843 // Allow sizeof(void)/alignof(void) as an extension. 1844 if (exprType->isVoidType()) { 1845 Diag(OpLoc, diag::ext_sizeof_void_type) 1846 << (isSizeof ? "sizeof" : "__alignof") << ExprRange; 1847 return false; 1848 } 1849 1850 if (RequireCompleteType(OpLoc, exprType, 1851 PDiag(diag::err_sizeof_alignof_incomplete_type) 1852 << int(!isSizeof) << ExprRange)) 1853 return true; 1854 1855 // Reject sizeof(interface) and sizeof(interface<proto>) in 64-bit mode. 1856 if (LangOpts.ObjCNonFragileABI && exprType->isObjCInterfaceType()) { 1857 Diag(OpLoc, diag::err_sizeof_nonfragile_interface) 1858 << exprType << isSizeof << ExprRange; 1859 return true; 1860 } 1861 1862 return false; 1863} 1864 1865bool Sema::CheckAlignOfExpr(Expr *E, SourceLocation OpLoc, 1866 const SourceRange &ExprRange) { 1867 E = E->IgnoreParens(); 1868 1869 // alignof decl is always ok. 1870 if (isa<DeclRefExpr>(E)) 1871 return false; 1872 1873 // Cannot know anything else if the expression is dependent. 1874 if (E->isTypeDependent()) 1875 return false; 1876 1877 if (E->getBitField()) { 1878 Diag(OpLoc, diag::err_sizeof_alignof_bitfield) << 1 << ExprRange; 1879 return true; 1880 } 1881 1882 // Alignment of a field access is always okay, so long as it isn't a 1883 // bit-field. 1884 if (MemberExpr *ME = dyn_cast<MemberExpr>(E)) 1885 if (isa<FieldDecl>(ME->getMemberDecl())) 1886 return false; 1887 1888 return CheckSizeOfAlignOfOperand(E->getType(), OpLoc, ExprRange, false); 1889} 1890 1891/// \brief Build a sizeof or alignof expression given a type operand. 1892Action::OwningExprResult 1893Sema::CreateSizeOfAlignOfExpr(TypeSourceInfo *TInfo, 1894 SourceLocation OpLoc, 1895 bool isSizeOf, SourceRange R) { 1896 if (!TInfo) 1897 return ExprError(); 1898 1899 QualType T = TInfo->getType(); 1900 1901 if (!T->isDependentType() && 1902 CheckSizeOfAlignOfOperand(T, OpLoc, R, isSizeOf)) 1903 return ExprError(); 1904 1905 // C99 6.5.3.4p4: the type (an unsigned integer type) is size_t. 1906 return Owned(new (Context) SizeOfAlignOfExpr(isSizeOf, TInfo, 1907 Context.getSizeType(), OpLoc, 1908 R.getEnd())); 1909} 1910 1911/// \brief Build a sizeof or alignof expression given an expression 1912/// operand. 1913Action::OwningExprResult 1914Sema::CreateSizeOfAlignOfExpr(Expr *E, SourceLocation OpLoc, 1915 bool isSizeOf, SourceRange R) { 1916 // Verify that the operand is valid. 1917 bool isInvalid = false; 1918 if (E->isTypeDependent()) { 1919 // Delay type-checking for type-dependent expressions. 1920 } else if (!isSizeOf) { 1921 isInvalid = CheckAlignOfExpr(E, OpLoc, R); 1922 } else if (E->getBitField()) { // C99 6.5.3.4p1. 1923 Diag(OpLoc, diag::err_sizeof_alignof_bitfield) << 0; 1924 isInvalid = true; 1925 } else { 1926 isInvalid = CheckSizeOfAlignOfOperand(E->getType(), OpLoc, R, true); 1927 } 1928 1929 if (isInvalid) 1930 return ExprError(); 1931 1932 // C99 6.5.3.4p4: the type (an unsigned integer type) is size_t. 1933 return Owned(new (Context) SizeOfAlignOfExpr(isSizeOf, E, 1934 Context.getSizeType(), OpLoc, 1935 R.getEnd())); 1936} 1937 1938/// ActOnSizeOfAlignOfExpr - Handle @c sizeof(type) and @c sizeof @c expr and 1939/// the same for @c alignof and @c __alignof 1940/// Note that the ArgRange is invalid if isType is false. 1941Action::OwningExprResult 1942Sema::ActOnSizeOfAlignOfExpr(SourceLocation OpLoc, bool isSizeof, bool isType, 1943 void *TyOrEx, const SourceRange &ArgRange) { 1944 // If error parsing type, ignore. 1945 if (TyOrEx == 0) return ExprError(); 1946 1947 if (isType) { 1948 TypeSourceInfo *TInfo; 1949 (void) GetTypeFromParser(TyOrEx, &TInfo); 1950 return CreateSizeOfAlignOfExpr(TInfo, OpLoc, isSizeof, ArgRange); 1951 } 1952 1953 Expr *ArgEx = (Expr *)TyOrEx; 1954 Action::OwningExprResult Result 1955 = CreateSizeOfAlignOfExpr(ArgEx, OpLoc, isSizeof, ArgEx->getSourceRange()); 1956 1957 if (Result.isInvalid()) 1958 DeleteExpr(ArgEx); 1959 1960 return move(Result); 1961} 1962 1963QualType Sema::CheckRealImagOperand(Expr *&V, SourceLocation Loc, bool isReal) { 1964 if (V->isTypeDependent()) 1965 return Context.DependentTy; 1966 1967 // These operators return the element type of a complex type. 1968 if (const ComplexType *CT = V->getType()->getAs<ComplexType>()) 1969 return CT->getElementType(); 1970 1971 // Otherwise they pass through real integer and floating point types here. 1972 if (V->getType()->isArithmeticType()) 1973 return V->getType(); 1974 1975 // Reject anything else. 1976 Diag(Loc, diag::err_realimag_invalid_type) << V->getType() 1977 << (isReal ? "__real" : "__imag"); 1978 return QualType(); 1979} 1980 1981 1982 1983Action::OwningExprResult 1984Sema::ActOnPostfixUnaryOp(Scope *S, SourceLocation OpLoc, 1985 tok::TokenKind Kind, ExprArg Input) { 1986 UnaryOperator::Opcode Opc; 1987 switch (Kind) { 1988 default: assert(0 && "Unknown unary op!"); 1989 case tok::plusplus: Opc = UnaryOperator::PostInc; break; 1990 case tok::minusminus: Opc = UnaryOperator::PostDec; break; 1991 } 1992 1993 return BuildUnaryOp(S, OpLoc, Opc, move(Input)); 1994} 1995 1996Action::OwningExprResult 1997Sema::ActOnArraySubscriptExpr(Scope *S, ExprArg Base, SourceLocation LLoc, 1998 ExprArg Idx, SourceLocation RLoc) { 1999 // Since this might be a postfix expression, get rid of ParenListExprs. 2000 Base = MaybeConvertParenListExprToParenExpr(S, move(Base)); 2001 2002 Expr *LHSExp = static_cast<Expr*>(Base.get()), 2003 *RHSExp = static_cast<Expr*>(Idx.get()); 2004 2005 if (getLangOptions().CPlusPlus && 2006 (LHSExp->isTypeDependent() || RHSExp->isTypeDependent())) { 2007 Base.release(); 2008 Idx.release(); 2009 return Owned(new (Context) ArraySubscriptExpr(LHSExp, RHSExp, 2010 Context.DependentTy, RLoc)); 2011 } 2012 2013 if (getLangOptions().CPlusPlus && 2014 (LHSExp->getType()->isRecordType() || 2015 LHSExp->getType()->isEnumeralType() || 2016 RHSExp->getType()->isRecordType() || 2017 RHSExp->getType()->isEnumeralType())) { 2018 return CreateOverloadedArraySubscriptExpr(LLoc, RLoc, move(Base),move(Idx)); 2019 } 2020 2021 return CreateBuiltinArraySubscriptExpr(move(Base), LLoc, move(Idx), RLoc); 2022} 2023 2024 2025Action::OwningExprResult 2026Sema::CreateBuiltinArraySubscriptExpr(ExprArg Base, SourceLocation LLoc, 2027 ExprArg Idx, SourceLocation RLoc) { 2028 Expr *LHSExp = static_cast<Expr*>(Base.get()); 2029 Expr *RHSExp = static_cast<Expr*>(Idx.get()); 2030 2031 // Perform default conversions. 2032 DefaultFunctionArrayConversion(LHSExp); 2033 DefaultFunctionArrayConversion(RHSExp); 2034 2035 QualType LHSTy = LHSExp->getType(), RHSTy = RHSExp->getType(); 2036 2037 // C99 6.5.2.1p2: the expression e1[e2] is by definition precisely equivalent 2038 // to the expression *((e1)+(e2)). This means the array "Base" may actually be 2039 // in the subscript position. As a result, we need to derive the array base 2040 // and index from the expression types. 2041 Expr *BaseExpr, *IndexExpr; 2042 QualType ResultType; 2043 if (LHSTy->isDependentType() || RHSTy->isDependentType()) { 2044 BaseExpr = LHSExp; 2045 IndexExpr = RHSExp; 2046 ResultType = Context.DependentTy; 2047 } else if (const PointerType *PTy = LHSTy->getAs<PointerType>()) { 2048 BaseExpr = LHSExp; 2049 IndexExpr = RHSExp; 2050 ResultType = PTy->getPointeeType(); 2051 } else if (const PointerType *PTy = RHSTy->getAs<PointerType>()) { 2052 // Handle the uncommon case of "123[Ptr]". 2053 BaseExpr = RHSExp; 2054 IndexExpr = LHSExp; 2055 ResultType = PTy->getPointeeType(); 2056 } else if (const ObjCObjectPointerType *PTy = 2057 LHSTy->getAs<ObjCObjectPointerType>()) { 2058 BaseExpr = LHSExp; 2059 IndexExpr = RHSExp; 2060 ResultType = PTy->getPointeeType(); 2061 } else if (const ObjCObjectPointerType *PTy = 2062 RHSTy->getAs<ObjCObjectPointerType>()) { 2063 // Handle the uncommon case of "123[Ptr]". 2064 BaseExpr = RHSExp; 2065 IndexExpr = LHSExp; 2066 ResultType = PTy->getPointeeType(); 2067 } else if (const VectorType *VTy = LHSTy->getAs<VectorType>()) { 2068 BaseExpr = LHSExp; // vectors: V[123] 2069 IndexExpr = RHSExp; 2070 2071 // FIXME: need to deal with const... 2072 ResultType = VTy->getElementType(); 2073 } else if (LHSTy->isArrayType()) { 2074 // If we see an array that wasn't promoted by 2075 // DefaultFunctionArrayConversion, it must be an array that 2076 // wasn't promoted because of the C90 rule that doesn't 2077 // allow promoting non-lvalue arrays. Warn, then 2078 // force the promotion here. 2079 Diag(LHSExp->getLocStart(), diag::ext_subscript_non_lvalue) << 2080 LHSExp->getSourceRange(); 2081 ImpCastExprToType(LHSExp, Context.getArrayDecayedType(LHSTy), 2082 CastExpr::CK_ArrayToPointerDecay); 2083 LHSTy = LHSExp->getType(); 2084 2085 BaseExpr = LHSExp; 2086 IndexExpr = RHSExp; 2087 ResultType = LHSTy->getAs<PointerType>()->getPointeeType(); 2088 } else if (RHSTy->isArrayType()) { 2089 // Same as previous, except for 123[f().a] case 2090 Diag(RHSExp->getLocStart(), diag::ext_subscript_non_lvalue) << 2091 RHSExp->getSourceRange(); 2092 ImpCastExprToType(RHSExp, Context.getArrayDecayedType(RHSTy), 2093 CastExpr::CK_ArrayToPointerDecay); 2094 RHSTy = RHSExp->getType(); 2095 2096 BaseExpr = RHSExp; 2097 IndexExpr = LHSExp; 2098 ResultType = RHSTy->getAs<PointerType>()->getPointeeType(); 2099 } else { 2100 return ExprError(Diag(LLoc, diag::err_typecheck_subscript_value) 2101 << LHSExp->getSourceRange() << RHSExp->getSourceRange()); 2102 } 2103 // C99 6.5.2.1p1 2104 if (!(IndexExpr->getType()->isIntegerType() && 2105 IndexExpr->getType()->isScalarType()) && !IndexExpr->isTypeDependent()) 2106 return ExprError(Diag(LLoc, diag::err_typecheck_subscript_not_integer) 2107 << IndexExpr->getSourceRange()); 2108 2109 if ((IndexExpr->getType()->isSpecificBuiltinType(BuiltinType::Char_S) || 2110 IndexExpr->getType()->isSpecificBuiltinType(BuiltinType::Char_U)) 2111 && !IndexExpr->isTypeDependent()) 2112 Diag(LLoc, diag::warn_subscript_is_char) << IndexExpr->getSourceRange(); 2113 2114 // C99 6.5.2.1p1: "shall have type "pointer to *object* type". Similarly, 2115 // C++ [expr.sub]p1: The type "T" shall be a completely-defined object 2116 // type. Note that Functions are not objects, and that (in C99 parlance) 2117 // incomplete types are not object types. 2118 if (ResultType->isFunctionType()) { 2119 Diag(BaseExpr->getLocStart(), diag::err_subscript_function_type) 2120 << ResultType << BaseExpr->getSourceRange(); 2121 return ExprError(); 2122 } 2123 2124 if (!ResultType->isDependentType() && 2125 RequireCompleteType(LLoc, ResultType, 2126 PDiag(diag::err_subscript_incomplete_type) 2127 << BaseExpr->getSourceRange())) 2128 return ExprError(); 2129 2130 // Diagnose bad cases where we step over interface counts. 2131 if (ResultType->isObjCInterfaceType() && LangOpts.ObjCNonFragileABI) { 2132 Diag(LLoc, diag::err_subscript_nonfragile_interface) 2133 << ResultType << BaseExpr->getSourceRange(); 2134 return ExprError(); 2135 } 2136 2137 Base.release(); 2138 Idx.release(); 2139 return Owned(new (Context) ArraySubscriptExpr(LHSExp, RHSExp, 2140 ResultType, RLoc)); 2141} 2142 2143QualType Sema:: 2144CheckExtVectorComponent(QualType baseType, SourceLocation OpLoc, 2145 const IdentifierInfo *CompName, 2146 SourceLocation CompLoc) { 2147 // FIXME: Share logic with ExtVectorElementExpr::containsDuplicateElements, 2148 // see FIXME there. 2149 // 2150 // FIXME: This logic can be greatly simplified by splitting it along 2151 // halving/not halving and reworking the component checking. 2152 const ExtVectorType *vecType = baseType->getAs<ExtVectorType>(); 2153 2154 // The vector accessor can't exceed the number of elements. 2155 const char *compStr = CompName->getNameStart(); 2156 2157 // This flag determines whether or not the component is one of the four 2158 // special names that indicate a subset of exactly half the elements are 2159 // to be selected. 2160 bool HalvingSwizzle = false; 2161 2162 // This flag determines whether or not CompName has an 's' char prefix, 2163 // indicating that it is a string of hex values to be used as vector indices. 2164 bool HexSwizzle = *compStr == 's' || *compStr == 'S'; 2165 2166 // Check that we've found one of the special components, or that the component 2167 // names must come from the same set. 2168 if (!strcmp(compStr, "hi") || !strcmp(compStr, "lo") || 2169 !strcmp(compStr, "even") || !strcmp(compStr, "odd")) { 2170 HalvingSwizzle = true; 2171 } else if (vecType->getPointAccessorIdx(*compStr) != -1) { 2172 do 2173 compStr++; 2174 while (*compStr && vecType->getPointAccessorIdx(*compStr) != -1); 2175 } else if (HexSwizzle || vecType->getNumericAccessorIdx(*compStr) != -1) { 2176 do 2177 compStr++; 2178 while (*compStr && vecType->getNumericAccessorIdx(*compStr) != -1); 2179 } 2180 2181 if (!HalvingSwizzle && *compStr) { 2182 // We didn't get to the end of the string. This means the component names 2183 // didn't come from the same set *or* we encountered an illegal name. 2184 Diag(OpLoc, diag::err_ext_vector_component_name_illegal) 2185 << std::string(compStr,compStr+1) << SourceRange(CompLoc); 2186 return QualType(); 2187 } 2188 2189 // Ensure no component accessor exceeds the width of the vector type it 2190 // operates on. 2191 if (!HalvingSwizzle) { 2192 compStr = CompName->getNameStart(); 2193 2194 if (HexSwizzle) 2195 compStr++; 2196 2197 while (*compStr) { 2198 if (!vecType->isAccessorWithinNumElements(*compStr++)) { 2199 Diag(OpLoc, diag::err_ext_vector_component_exceeds_length) 2200 << baseType << SourceRange(CompLoc); 2201 return QualType(); 2202 } 2203 } 2204 } 2205 2206 // The component accessor looks fine - now we need to compute the actual type. 2207 // The vector type is implied by the component accessor. For example, 2208 // vec4.b is a float, vec4.xy is a vec2, vec4.rgb is a vec3, etc. 2209 // vec4.s0 is a float, vec4.s23 is a vec3, etc. 2210 // vec4.hi, vec4.lo, vec4.e, and vec4.o all return vec2. 2211 unsigned CompSize = HalvingSwizzle ? (vecType->getNumElements() + 1) / 2 2212 : CompName->getLength(); 2213 if (HexSwizzle) 2214 CompSize--; 2215 2216 if (CompSize == 1) 2217 return vecType->getElementType(); 2218 2219 QualType VT = Context.getExtVectorType(vecType->getElementType(), CompSize); 2220 // Now look up the TypeDefDecl from the vector type. Without this, 2221 // diagostics look bad. We want extended vector types to appear built-in. 2222 for (unsigned i = 0, E = ExtVectorDecls.size(); i != E; ++i) { 2223 if (ExtVectorDecls[i]->getUnderlyingType() == VT) 2224 return Context.getTypedefType(ExtVectorDecls[i]); 2225 } 2226 return VT; // should never get here (a typedef type should always be found). 2227} 2228 2229static Decl *FindGetterNameDeclFromProtocolList(const ObjCProtocolDecl*PDecl, 2230 IdentifierInfo *Member, 2231 const Selector &Sel, 2232 ASTContext &Context) { 2233 2234 if (ObjCPropertyDecl *PD = PDecl->FindPropertyDeclaration(Member)) 2235 return PD; 2236 if (ObjCMethodDecl *OMD = PDecl->getInstanceMethod(Sel)) 2237 return OMD; 2238 2239 for (ObjCProtocolDecl::protocol_iterator I = PDecl->protocol_begin(), 2240 E = PDecl->protocol_end(); I != E; ++I) { 2241 if (Decl *D = FindGetterNameDeclFromProtocolList(*I, Member, Sel, 2242 Context)) 2243 return D; 2244 } 2245 return 0; 2246} 2247 2248static Decl *FindGetterNameDecl(const ObjCObjectPointerType *QIdTy, 2249 IdentifierInfo *Member, 2250 const Selector &Sel, 2251 ASTContext &Context) { 2252 // Check protocols on qualified interfaces. 2253 Decl *GDecl = 0; 2254 for (ObjCObjectPointerType::qual_iterator I = QIdTy->qual_begin(), 2255 E = QIdTy->qual_end(); I != E; ++I) { 2256 if (ObjCPropertyDecl *PD = (*I)->FindPropertyDeclaration(Member)) { 2257 GDecl = PD; 2258 break; 2259 } 2260 // Also must look for a getter name which uses property syntax. 2261 if (ObjCMethodDecl *OMD = (*I)->getInstanceMethod(Sel)) { 2262 GDecl = OMD; 2263 break; 2264 } 2265 } 2266 if (!GDecl) { 2267 for (ObjCObjectPointerType::qual_iterator I = QIdTy->qual_begin(), 2268 E = QIdTy->qual_end(); I != E; ++I) { 2269 // Search in the protocol-qualifier list of current protocol. 2270 GDecl = FindGetterNameDeclFromProtocolList(*I, Member, Sel, Context); 2271 if (GDecl) 2272 return GDecl; 2273 } 2274 } 2275 return GDecl; 2276} 2277 2278Sema::OwningExprResult 2279Sema::ActOnDependentMemberExpr(ExprArg Base, QualType BaseType, 2280 bool IsArrow, SourceLocation OpLoc, 2281 const CXXScopeSpec &SS, 2282 NamedDecl *FirstQualifierInScope, 2283 DeclarationName Name, SourceLocation NameLoc, 2284 const TemplateArgumentListInfo *TemplateArgs) { 2285 Expr *BaseExpr = Base.takeAs<Expr>(); 2286 2287 // Even in dependent contexts, try to diagnose base expressions with 2288 // obviously wrong types, e.g.: 2289 // 2290 // T* t; 2291 // t.f; 2292 // 2293 // In Obj-C++, however, the above expression is valid, since it could be 2294 // accessing the 'f' property if T is an Obj-C interface. The extra check 2295 // allows this, while still reporting an error if T is a struct pointer. 2296 if (!IsArrow) { 2297 const PointerType *PT = BaseType->getAs<PointerType>(); 2298 if (PT && (!getLangOptions().ObjC1 || 2299 PT->getPointeeType()->isRecordType())) { 2300 assert(BaseExpr && "cannot happen with implicit member accesses"); 2301 Diag(NameLoc, diag::err_typecheck_member_reference_struct_union) 2302 << BaseType << BaseExpr->getSourceRange(); 2303 return ExprError(); 2304 } 2305 } 2306 2307 assert(BaseType->isDependentType() || Name.isDependentName()); 2308 2309 // Get the type being accessed in BaseType. If this is an arrow, the BaseExpr 2310 // must have pointer type, and the accessed type is the pointee. 2311 return Owned(CXXDependentScopeMemberExpr::Create(Context, BaseExpr, BaseType, 2312 IsArrow, OpLoc, 2313 static_cast<NestedNameSpecifier*>(SS.getScopeRep()), 2314 SS.getRange(), 2315 FirstQualifierInScope, 2316 Name, NameLoc, 2317 TemplateArgs)); 2318} 2319 2320/// We know that the given qualified member reference points only to 2321/// declarations which do not belong to the static type of the base 2322/// expression. Diagnose the problem. 2323static void DiagnoseQualifiedMemberReference(Sema &SemaRef, 2324 Expr *BaseExpr, 2325 QualType BaseType, 2326 const CXXScopeSpec &SS, 2327 const LookupResult &R) { 2328 // If this is an implicit member access, use a different set of 2329 // diagnostics. 2330 if (!BaseExpr) 2331 return DiagnoseInstanceReference(SemaRef, SS, R); 2332 2333 // FIXME: this is an exceedingly lame diagnostic for some of the more 2334 // complicated cases here. 2335 DeclContext *DC = R.getRepresentativeDecl()->getDeclContext(); 2336 SemaRef.Diag(R.getNameLoc(), diag::err_not_direct_base_or_virtual) 2337 << SS.getRange() << DC << BaseType; 2338} 2339 2340// Check whether the declarations we found through a nested-name 2341// specifier in a member expression are actually members of the base 2342// type. The restriction here is: 2343// 2344// C++ [expr.ref]p2: 2345// ... In these cases, the id-expression shall name a 2346// member of the class or of one of its base classes. 2347// 2348// So it's perfectly legitimate for the nested-name specifier to name 2349// an unrelated class, and for us to find an overload set including 2350// decls from classes which are not superclasses, as long as the decl 2351// we actually pick through overload resolution is from a superclass. 2352bool Sema::CheckQualifiedMemberReference(Expr *BaseExpr, 2353 QualType BaseType, 2354 const CXXScopeSpec &SS, 2355 const LookupResult &R) { 2356 const RecordType *BaseRT = BaseType->getAs<RecordType>(); 2357 if (!BaseRT) { 2358 // We can't check this yet because the base type is still 2359 // dependent. 2360 assert(BaseType->isDependentType()); 2361 return false; 2362 } 2363 CXXRecordDecl *BaseRecord = cast<CXXRecordDecl>(BaseRT->getDecl()); 2364 2365 for (LookupResult::iterator I = R.begin(), E = R.end(); I != E; ++I) { 2366 // If this is an implicit member reference and we find a 2367 // non-instance member, it's not an error. 2368 if (!BaseExpr && !IsInstanceMember((*I)->getUnderlyingDecl())) 2369 return false; 2370 2371 // Note that we use the DC of the decl, not the underlying decl. 2372 CXXRecordDecl *RecordD = cast<CXXRecordDecl>((*I)->getDeclContext()); 2373 while (RecordD->isAnonymousStructOrUnion()) 2374 RecordD = cast<CXXRecordDecl>(RecordD->getParent()); 2375 2376 llvm::SmallPtrSet<CXXRecordDecl*,4> MemberRecord; 2377 MemberRecord.insert(RecordD->getCanonicalDecl()); 2378 2379 if (!IsProvablyNotDerivedFrom(*this, BaseRecord, MemberRecord)) 2380 return false; 2381 } 2382 2383 DiagnoseQualifiedMemberReference(*this, BaseExpr, BaseType, SS, R); 2384 return true; 2385} 2386 2387static bool 2388LookupMemberExprInRecord(Sema &SemaRef, LookupResult &R, 2389 SourceRange BaseRange, const RecordType *RTy, 2390 SourceLocation OpLoc, const CXXScopeSpec &SS) { 2391 RecordDecl *RDecl = RTy->getDecl(); 2392 if (SemaRef.RequireCompleteType(OpLoc, QualType(RTy, 0), 2393 PDiag(diag::err_typecheck_incomplete_tag) 2394 << BaseRange)) 2395 return true; 2396 2397 DeclContext *DC = RDecl; 2398 if (SS.isSet()) { 2399 // If the member name was a qualified-id, look into the 2400 // nested-name-specifier. 2401 DC = SemaRef.computeDeclContext(SS, false); 2402 2403 if (SemaRef.RequireCompleteDeclContext(SS)) { 2404 SemaRef.Diag(SS.getRange().getEnd(), diag::err_typecheck_incomplete_tag) 2405 << SS.getRange() << DC; 2406 return true; 2407 } 2408 2409 assert(DC && "Cannot handle non-computable dependent contexts in lookup"); 2410 2411 if (!isa<TypeDecl>(DC)) { 2412 SemaRef.Diag(R.getNameLoc(), diag::err_qualified_member_nonclass) 2413 << DC << SS.getRange(); 2414 return true; 2415 } 2416 } 2417 2418 // The record definition is complete, now look up the member. 2419 SemaRef.LookupQualifiedName(R, DC); 2420 2421 if (!R.empty()) 2422 return false; 2423 2424 // We didn't find anything with the given name, so try to correct 2425 // for typos. 2426 DeclarationName Name = R.getLookupName(); 2427 if (SemaRef.CorrectTypo(R, 0, &SS, DC) && 2428 (isa<ValueDecl>(*R.begin()) || isa<FunctionTemplateDecl>(*R.begin()))) { 2429 SemaRef.Diag(R.getNameLoc(), diag::err_no_member_suggest) 2430 << Name << DC << R.getLookupName() << SS.getRange() 2431 << CodeModificationHint::CreateReplacement(R.getNameLoc(), 2432 R.getLookupName().getAsString()); 2433 if (NamedDecl *ND = R.getAsSingle<NamedDecl>()) 2434 SemaRef.Diag(ND->getLocation(), diag::note_previous_decl) 2435 << ND->getDeclName(); 2436 return false; 2437 } else { 2438 R.clear(); 2439 } 2440 2441 return false; 2442} 2443 2444Sema::OwningExprResult 2445Sema::BuildMemberReferenceExpr(ExprArg BaseArg, QualType BaseType, 2446 SourceLocation OpLoc, bool IsArrow, 2447 const CXXScopeSpec &SS, 2448 NamedDecl *FirstQualifierInScope, 2449 DeclarationName Name, SourceLocation NameLoc, 2450 const TemplateArgumentListInfo *TemplateArgs) { 2451 Expr *Base = BaseArg.takeAs<Expr>(); 2452 2453 if (BaseType->isDependentType() || 2454 (SS.isSet() && isDependentScopeSpecifier(SS))) 2455 return ActOnDependentMemberExpr(ExprArg(*this, Base), BaseType, 2456 IsArrow, OpLoc, 2457 SS, FirstQualifierInScope, 2458 Name, NameLoc, 2459 TemplateArgs); 2460 2461 LookupResult R(*this, Name, NameLoc, LookupMemberName); 2462 2463 // Implicit member accesses. 2464 if (!Base) { 2465 QualType RecordTy = BaseType; 2466 if (IsArrow) RecordTy = RecordTy->getAs<PointerType>()->getPointeeType(); 2467 if (LookupMemberExprInRecord(*this, R, SourceRange(), 2468 RecordTy->getAs<RecordType>(), 2469 OpLoc, SS)) 2470 return ExprError(); 2471 2472 // Explicit member accesses. 2473 } else { 2474 OwningExprResult Result = 2475 LookupMemberExpr(R, Base, IsArrow, OpLoc, 2476 SS, /*ObjCImpDecl*/ DeclPtrTy()); 2477 2478 if (Result.isInvalid()) { 2479 Owned(Base); 2480 return ExprError(); 2481 } 2482 2483 if (Result.get()) 2484 return move(Result); 2485 } 2486 2487 return BuildMemberReferenceExpr(ExprArg(*this, Base), BaseType, 2488 OpLoc, IsArrow, SS, FirstQualifierInScope, 2489 R, TemplateArgs); 2490} 2491 2492Sema::OwningExprResult 2493Sema::BuildMemberReferenceExpr(ExprArg Base, QualType BaseExprType, 2494 SourceLocation OpLoc, bool IsArrow, 2495 const CXXScopeSpec &SS, 2496 NamedDecl *FirstQualifierInScope, 2497 LookupResult &R, 2498 const TemplateArgumentListInfo *TemplateArgs) { 2499 Expr *BaseExpr = Base.takeAs<Expr>(); 2500 QualType BaseType = BaseExprType; 2501 if (IsArrow) { 2502 assert(BaseType->isPointerType()); 2503 BaseType = BaseType->getAs<PointerType>()->getPointeeType(); 2504 } 2505 2506 NestedNameSpecifier *Qualifier = 2507 static_cast<NestedNameSpecifier*>(SS.getScopeRep()); 2508 DeclarationName MemberName = R.getLookupName(); 2509 SourceLocation MemberLoc = R.getNameLoc(); 2510 2511 if (R.isAmbiguous()) 2512 return ExprError(); 2513 2514 if (R.empty()) { 2515 // Rederive where we looked up. 2516 DeclContext *DC = (SS.isSet() 2517 ? computeDeclContext(SS, false) 2518 : BaseType->getAs<RecordType>()->getDecl()); 2519 2520 Diag(R.getNameLoc(), diag::err_no_member) 2521 << MemberName << DC 2522 << (BaseExpr ? BaseExpr->getSourceRange() : SourceRange()); 2523 return ExprError(); 2524 } 2525 2526 // Diagnose lookups that find only declarations from a non-base 2527 // type. This is possible for either qualified lookups (which may 2528 // have been qualified with an unrelated type) or implicit member 2529 // expressions (which were found with unqualified lookup and thus 2530 // may have come from an enclosing scope). Note that it's okay for 2531 // lookup to find declarations from a non-base type as long as those 2532 // aren't the ones picked by overload resolution. 2533 if ((SS.isSet() || !BaseExpr || 2534 (isa<CXXThisExpr>(BaseExpr) && 2535 cast<CXXThisExpr>(BaseExpr)->isImplicit())) && 2536 CheckQualifiedMemberReference(BaseExpr, BaseType, SS, R)) 2537 return ExprError(); 2538 2539 // Construct an unresolved result if we in fact got an unresolved 2540 // result. 2541 if (R.isOverloadedResult() || R.isUnresolvableResult()) { 2542 bool Dependent = 2543 BaseExprType->isDependentType() || 2544 R.isUnresolvableResult() || 2545 UnresolvedLookupExpr::ComputeDependence(R.begin(), R.end(), TemplateArgs); 2546 2547 UnresolvedMemberExpr *MemExpr 2548 = UnresolvedMemberExpr::Create(Context, Dependent, 2549 R.isUnresolvableResult(), 2550 BaseExpr, BaseExprType, 2551 IsArrow, OpLoc, 2552 Qualifier, SS.getRange(), 2553 MemberName, MemberLoc, 2554 TemplateArgs); 2555 for (LookupResult::iterator I = R.begin(), E = R.end(); I != E; ++I) 2556 MemExpr->addDecl(*I); 2557 2558 return Owned(MemExpr); 2559 } 2560 2561 assert(R.isSingleResult()); 2562 NamedDecl *MemberDecl = R.getFoundDecl(); 2563 2564 // FIXME: diagnose the presence of template arguments now. 2565 2566 // If the decl being referenced had an error, return an error for this 2567 // sub-expr without emitting another error, in order to avoid cascading 2568 // error cases. 2569 if (MemberDecl->isInvalidDecl()) 2570 return ExprError(); 2571 2572 // Handle the implicit-member-access case. 2573 if (!BaseExpr) { 2574 // If this is not an instance member, convert to a non-member access. 2575 if (!IsInstanceMember(MemberDecl)) 2576 return BuildDeclarationNameExpr(SS, R.getNameLoc(), MemberDecl); 2577 2578 SourceLocation Loc = R.getNameLoc(); 2579 if (SS.getRange().isValid()) 2580 Loc = SS.getRange().getBegin(); 2581 BaseExpr = new (Context) CXXThisExpr(Loc, BaseExprType,/*isImplicit=*/true); 2582 } 2583 2584 bool ShouldCheckUse = true; 2585 if (CXXMethodDecl *MD = dyn_cast<CXXMethodDecl>(MemberDecl)) { 2586 // Don't diagnose the use of a virtual member function unless it's 2587 // explicitly qualified. 2588 if (MD->isVirtual() && !SS.isSet()) 2589 ShouldCheckUse = false; 2590 } 2591 2592 // Check the use of this member. 2593 if (ShouldCheckUse && DiagnoseUseOfDecl(MemberDecl, MemberLoc)) { 2594 Owned(BaseExpr); 2595 return ExprError(); 2596 } 2597 2598 if (FieldDecl *FD = dyn_cast<FieldDecl>(MemberDecl)) { 2599 // We may have found a field within an anonymous union or struct 2600 // (C++ [class.union]). 2601 if (cast<RecordDecl>(FD->getDeclContext())->isAnonymousStructOrUnion() && 2602 !BaseType->getAs<RecordType>()->getDecl()->isAnonymousStructOrUnion()) 2603 return BuildAnonymousStructUnionMemberReference(MemberLoc, FD, 2604 BaseExpr, OpLoc); 2605 2606 // Figure out the type of the member; see C99 6.5.2.3p3, C++ [expr.ref] 2607 QualType MemberType = FD->getType(); 2608 if (const ReferenceType *Ref = MemberType->getAs<ReferenceType>()) 2609 MemberType = Ref->getPointeeType(); 2610 else { 2611 Qualifiers BaseQuals = BaseType.getQualifiers(); 2612 BaseQuals.removeObjCGCAttr(); 2613 if (FD->isMutable()) BaseQuals.removeConst(); 2614 2615 Qualifiers MemberQuals 2616 = Context.getCanonicalType(MemberType).getQualifiers(); 2617 2618 Qualifiers Combined = BaseQuals + MemberQuals; 2619 if (Combined != MemberQuals) 2620 MemberType = Context.getQualifiedType(MemberType, Combined); 2621 } 2622 2623 MarkDeclarationReferenced(MemberLoc, FD); 2624 if (PerformObjectMemberConversion(BaseExpr, FD)) 2625 return ExprError(); 2626 return Owned(BuildMemberExpr(Context, BaseExpr, IsArrow, SS, 2627 FD, MemberLoc, MemberType)); 2628 } 2629 2630 if (VarDecl *Var = dyn_cast<VarDecl>(MemberDecl)) { 2631 MarkDeclarationReferenced(MemberLoc, Var); 2632 return Owned(BuildMemberExpr(Context, BaseExpr, IsArrow, SS, 2633 Var, MemberLoc, 2634 Var->getType().getNonReferenceType())); 2635 } 2636 2637 if (FunctionDecl *MemberFn = dyn_cast<FunctionDecl>(MemberDecl)) { 2638 MarkDeclarationReferenced(MemberLoc, MemberDecl); 2639 return Owned(BuildMemberExpr(Context, BaseExpr, IsArrow, SS, 2640 MemberFn, MemberLoc, 2641 MemberFn->getType())); 2642 } 2643 2644 if (EnumConstantDecl *Enum = dyn_cast<EnumConstantDecl>(MemberDecl)) { 2645 MarkDeclarationReferenced(MemberLoc, MemberDecl); 2646 return Owned(BuildMemberExpr(Context, BaseExpr, IsArrow, SS, 2647 Enum, MemberLoc, Enum->getType())); 2648 } 2649 2650 Owned(BaseExpr); 2651 2652 if (isa<TypeDecl>(MemberDecl)) 2653 return ExprError(Diag(MemberLoc,diag::err_typecheck_member_reference_type) 2654 << MemberName << int(IsArrow)); 2655 2656 // We found a declaration kind that we didn't expect. This is a 2657 // generic error message that tells the user that she can't refer 2658 // to this member with '.' or '->'. 2659 return ExprError(Diag(MemberLoc, 2660 diag::err_typecheck_member_reference_unknown) 2661 << MemberName << int(IsArrow)); 2662} 2663 2664/// Look up the given member of the given non-type-dependent 2665/// expression. This can return in one of two ways: 2666/// * If it returns a sentinel null-but-valid result, the caller will 2667/// assume that lookup was performed and the results written into 2668/// the provided structure. It will take over from there. 2669/// * Otherwise, the returned expression will be produced in place of 2670/// an ordinary member expression. 2671/// 2672/// The ObjCImpDecl bit is a gross hack that will need to be properly 2673/// fixed for ObjC++. 2674Sema::OwningExprResult 2675Sema::LookupMemberExpr(LookupResult &R, Expr *&BaseExpr, 2676 bool &IsArrow, SourceLocation OpLoc, 2677 const CXXScopeSpec &SS, 2678 DeclPtrTy ObjCImpDecl) { 2679 assert(BaseExpr && "no base expression"); 2680 2681 // Perform default conversions. 2682 DefaultFunctionArrayConversion(BaseExpr); 2683 2684 QualType BaseType = BaseExpr->getType(); 2685 assert(!BaseType->isDependentType()); 2686 2687 DeclarationName MemberName = R.getLookupName(); 2688 SourceLocation MemberLoc = R.getNameLoc(); 2689 2690 // If the user is trying to apply -> or . to a function pointer 2691 // type, it's probably because they forgot parentheses to call that 2692 // function. Suggest the addition of those parentheses, build the 2693 // call, and continue on. 2694 if (const PointerType *Ptr = BaseType->getAs<PointerType>()) { 2695 if (const FunctionProtoType *Fun 2696 = Ptr->getPointeeType()->getAs<FunctionProtoType>()) { 2697 QualType ResultTy = Fun->getResultType(); 2698 if (Fun->getNumArgs() == 0 && 2699 ((!IsArrow && ResultTy->isRecordType()) || 2700 (IsArrow && ResultTy->isPointerType() && 2701 ResultTy->getAs<PointerType>()->getPointeeType() 2702 ->isRecordType()))) { 2703 SourceLocation Loc = PP.getLocForEndOfToken(BaseExpr->getLocEnd()); 2704 Diag(Loc, diag::err_member_reference_needs_call) 2705 << QualType(Fun, 0) 2706 << CodeModificationHint::CreateInsertion(Loc, "()"); 2707 2708 OwningExprResult NewBase 2709 = ActOnCallExpr(0, ExprArg(*this, BaseExpr), Loc, 2710 MultiExprArg(*this, 0, 0), 0, Loc); 2711 if (NewBase.isInvalid()) 2712 return ExprError(); 2713 2714 BaseExpr = NewBase.takeAs<Expr>(); 2715 DefaultFunctionArrayConversion(BaseExpr); 2716 BaseType = BaseExpr->getType(); 2717 } 2718 } 2719 } 2720 2721 // If this is an Objective-C pseudo-builtin and a definition is provided then 2722 // use that. 2723 if (BaseType->isObjCIdType()) { 2724 if (IsArrow) { 2725 // Handle the following exceptional case PObj->isa. 2726 if (const ObjCObjectPointerType *OPT = 2727 BaseType->getAs<ObjCObjectPointerType>()) { 2728 if (OPT->getPointeeType()->isSpecificBuiltinType(BuiltinType::ObjCId) && 2729 MemberName.getAsIdentifierInfo()->isStr("isa")) 2730 return Owned(new (Context) ObjCIsaExpr(BaseExpr, true, MemberLoc, 2731 Context.getObjCClassType())); 2732 } 2733 } 2734 // We have an 'id' type. Rather than fall through, we check if this 2735 // is a reference to 'isa'. 2736 if (BaseType != Context.ObjCIdRedefinitionType) { 2737 BaseType = Context.ObjCIdRedefinitionType; 2738 ImpCastExprToType(BaseExpr, BaseType, CastExpr::CK_BitCast); 2739 } 2740 } 2741 2742 // If this is an Objective-C pseudo-builtin and a definition is provided then 2743 // use that. 2744 if (Context.isObjCSelType(BaseType)) { 2745 // We have an 'SEL' type. Rather than fall through, we check if this 2746 // is a reference to 'sel_id'. 2747 if (BaseType != Context.ObjCSelRedefinitionType) { 2748 BaseType = Context.ObjCSelRedefinitionType; 2749 ImpCastExprToType(BaseExpr, BaseType, CastExpr::CK_BitCast); 2750 } 2751 } 2752 2753 assert(!BaseType.isNull() && "no type for member expression"); 2754 2755 // Handle properties on ObjC 'Class' types. 2756 if (!IsArrow && BaseType->isObjCClassType()) { 2757 // Also must look for a getter name which uses property syntax. 2758 IdentifierInfo *Member = MemberName.getAsIdentifierInfo(); 2759 Selector Sel = PP.getSelectorTable().getNullarySelector(Member); 2760 if (ObjCMethodDecl *MD = getCurMethodDecl()) { 2761 ObjCInterfaceDecl *IFace = MD->getClassInterface(); 2762 ObjCMethodDecl *Getter; 2763 // FIXME: need to also look locally in the implementation. 2764 if ((Getter = IFace->lookupClassMethod(Sel))) { 2765 // Check the use of this method. 2766 if (DiagnoseUseOfDecl(Getter, MemberLoc)) 2767 return ExprError(); 2768 } 2769 // If we found a getter then this may be a valid dot-reference, we 2770 // will look for the matching setter, in case it is needed. 2771 Selector SetterSel = 2772 SelectorTable::constructSetterName(PP.getIdentifierTable(), 2773 PP.getSelectorTable(), Member); 2774 ObjCMethodDecl *Setter = IFace->lookupClassMethod(SetterSel); 2775 if (!Setter) { 2776 // If this reference is in an @implementation, also check for 'private' 2777 // methods. 2778 Setter = IFace->lookupPrivateInstanceMethod(SetterSel); 2779 } 2780 // Look through local category implementations associated with the class. 2781 if (!Setter) 2782 Setter = IFace->getCategoryClassMethod(SetterSel); 2783 2784 if (Setter && DiagnoseUseOfDecl(Setter, MemberLoc)) 2785 return ExprError(); 2786 2787 if (Getter || Setter) { 2788 QualType PType; 2789 2790 if (Getter) 2791 PType = Getter->getResultType(); 2792 else 2793 // Get the expression type from Setter's incoming parameter. 2794 PType = (*(Setter->param_end() -1))->getType(); 2795 // FIXME: we must check that the setter has property type. 2796 return Owned(new (Context) ObjCImplicitSetterGetterRefExpr(Getter, 2797 PType, 2798 Setter, MemberLoc, BaseExpr)); 2799 } 2800 return ExprError(Diag(MemberLoc, diag::err_property_not_found) 2801 << MemberName << BaseType); 2802 } 2803 } 2804 2805 if (BaseType->isObjCClassType() && 2806 BaseType != Context.ObjCClassRedefinitionType) { 2807 BaseType = Context.ObjCClassRedefinitionType; 2808 ImpCastExprToType(BaseExpr, BaseType, CastExpr::CK_BitCast); 2809 } 2810 2811 if (IsArrow) { 2812 if (const PointerType *PT = BaseType->getAs<PointerType>()) 2813 BaseType = PT->getPointeeType(); 2814 else if (BaseType->isObjCObjectPointerType()) 2815 ; 2816 else if (BaseType->isRecordType()) { 2817 // Recover from arrow accesses to records, e.g.: 2818 // struct MyRecord foo; 2819 // foo->bar 2820 // This is actually well-formed in C++ if MyRecord has an 2821 // overloaded operator->, but that should have been dealt with 2822 // by now. 2823 Diag(OpLoc, diag::err_typecheck_member_reference_suggestion) 2824 << BaseType << int(IsArrow) << BaseExpr->getSourceRange() 2825 << CodeModificationHint::CreateReplacement(OpLoc, "."); 2826 IsArrow = false; 2827 } else { 2828 Diag(MemberLoc, diag::err_typecheck_member_reference_arrow) 2829 << BaseType << BaseExpr->getSourceRange(); 2830 return ExprError(); 2831 } 2832 } else { 2833 // Recover from dot accesses to pointers, e.g.: 2834 // type *foo; 2835 // foo.bar 2836 // This is actually well-formed in two cases: 2837 // - 'type' is an Objective C type 2838 // - 'bar' is a pseudo-destructor name which happens to refer to 2839 // the appropriate pointer type 2840 if (MemberName.getNameKind() != DeclarationName::CXXDestructorName) { 2841 const PointerType *PT = BaseType->getAs<PointerType>(); 2842 if (PT && PT->getPointeeType()->isRecordType()) { 2843 Diag(OpLoc, diag::err_typecheck_member_reference_suggestion) 2844 << BaseType << int(IsArrow) << BaseExpr->getSourceRange() 2845 << CodeModificationHint::CreateReplacement(OpLoc, "->"); 2846 BaseType = PT->getPointeeType(); 2847 IsArrow = true; 2848 } 2849 } 2850 } 2851 2852 // Handle field access to simple records. This also handles access 2853 // to fields of the ObjC 'id' struct. 2854 if (const RecordType *RTy = BaseType->getAs<RecordType>()) { 2855 if (LookupMemberExprInRecord(*this, R, BaseExpr->getSourceRange(), 2856 RTy, OpLoc, SS)) 2857 return ExprError(); 2858 return Owned((Expr*) 0); 2859 } 2860 2861 // Handle pseudo-destructors (C++ [expr.pseudo]). Since anything referring 2862 // into a record type was handled above, any destructor we see here is a 2863 // pseudo-destructor. 2864 if (MemberName.getNameKind() == DeclarationName::CXXDestructorName) { 2865 // C++ [expr.pseudo]p2: 2866 // The left hand side of the dot operator shall be of scalar type. The 2867 // left hand side of the arrow operator shall be of pointer to scalar 2868 // type. 2869 if (!BaseType->isScalarType()) 2870 return Owned(Diag(OpLoc, diag::err_pseudo_dtor_base_not_scalar) 2871 << BaseType << BaseExpr->getSourceRange()); 2872 2873 // [...] The type designated by the pseudo-destructor-name shall be the 2874 // same as the object type. 2875 if (!MemberName.getCXXNameType()->isDependentType() && 2876 !Context.hasSameUnqualifiedType(BaseType, MemberName.getCXXNameType())) 2877 return Owned(Diag(OpLoc, diag::err_pseudo_dtor_type_mismatch) 2878 << BaseType << MemberName.getCXXNameType() 2879 << BaseExpr->getSourceRange() << SourceRange(MemberLoc)); 2880 2881 // [...] Furthermore, the two type-names in a pseudo-destructor-name of 2882 // the form 2883 // 2884 // ::[opt] nested-name-specifier[opt] type-name :: ̃ type-name 2885 // 2886 // shall designate the same scalar type. 2887 // 2888 // FIXME: DPG can't see any way to trigger this particular clause, so it 2889 // isn't checked here. 2890 2891 // FIXME: We've lost the precise spelling of the type by going through 2892 // DeclarationName. Can we do better? 2893 return Owned(new (Context) CXXPseudoDestructorExpr(Context, BaseExpr, 2894 IsArrow, OpLoc, 2895 (NestedNameSpecifier *) SS.getScopeRep(), 2896 SS.getRange(), 2897 MemberName.getCXXNameType(), 2898 MemberLoc)); 2899 } 2900 2901 // Handle access to Objective-C instance variables, such as "Obj->ivar" and 2902 // (*Obj).ivar. 2903 if ((IsArrow && BaseType->isObjCObjectPointerType()) || 2904 (!IsArrow && BaseType->isObjCInterfaceType())) { 2905 const ObjCObjectPointerType *OPT = BaseType->getAs<ObjCObjectPointerType>(); 2906 const ObjCInterfaceType *IFaceT = 2907 OPT ? OPT->getInterfaceType() : BaseType->getAs<ObjCInterfaceType>(); 2908 if (IFaceT) { 2909 IdentifierInfo *Member = MemberName.getAsIdentifierInfo(); 2910 2911 ObjCInterfaceDecl *IDecl = IFaceT->getDecl(); 2912 ObjCInterfaceDecl *ClassDeclared; 2913 ObjCIvarDecl *IV = IDecl->lookupInstanceVariable(Member, ClassDeclared); 2914 2915 if (!IV) { 2916 // Attempt to correct for typos in ivar names. 2917 LookupResult Res(*this, R.getLookupName(), R.getNameLoc(), 2918 LookupMemberName); 2919 if (CorrectTypo(Res, 0, 0, IDecl) && 2920 (IV = Res.getAsSingle<ObjCIvarDecl>())) { 2921 Diag(R.getNameLoc(), 2922 diag::err_typecheck_member_reference_ivar_suggest) 2923 << IDecl->getDeclName() << MemberName << IV->getDeclName() 2924 << CodeModificationHint::CreateReplacement(R.getNameLoc(), 2925 IV->getNameAsString()); 2926 Diag(IV->getLocation(), diag::note_previous_decl) 2927 << IV->getDeclName(); 2928 } 2929 } 2930 2931 if (IV) { 2932 // If the decl being referenced had an error, return an error for this 2933 // sub-expr without emitting another error, in order to avoid cascading 2934 // error cases. 2935 if (IV->isInvalidDecl()) 2936 return ExprError(); 2937 2938 // Check whether we can reference this field. 2939 if (DiagnoseUseOfDecl(IV, MemberLoc)) 2940 return ExprError(); 2941 if (IV->getAccessControl() != ObjCIvarDecl::Public && 2942 IV->getAccessControl() != ObjCIvarDecl::Package) { 2943 ObjCInterfaceDecl *ClassOfMethodDecl = 0; 2944 if (ObjCMethodDecl *MD = getCurMethodDecl()) 2945 ClassOfMethodDecl = MD->getClassInterface(); 2946 else if (ObjCImpDecl && getCurFunctionDecl()) { 2947 // Case of a c-function declared inside an objc implementation. 2948 // FIXME: For a c-style function nested inside an objc implementation 2949 // class, there is no implementation context available, so we pass 2950 // down the context as argument to this routine. Ideally, this context 2951 // need be passed down in the AST node and somehow calculated from the 2952 // AST for a function decl. 2953 Decl *ImplDecl = ObjCImpDecl.getAs<Decl>(); 2954 if (ObjCImplementationDecl *IMPD = 2955 dyn_cast<ObjCImplementationDecl>(ImplDecl)) 2956 ClassOfMethodDecl = IMPD->getClassInterface(); 2957 else if (ObjCCategoryImplDecl* CatImplClass = 2958 dyn_cast<ObjCCategoryImplDecl>(ImplDecl)) 2959 ClassOfMethodDecl = CatImplClass->getClassInterface(); 2960 } 2961 2962 if (IV->getAccessControl() == ObjCIvarDecl::Private) { 2963 if (ClassDeclared != IDecl || 2964 ClassOfMethodDecl != ClassDeclared) 2965 Diag(MemberLoc, diag::error_private_ivar_access) 2966 << IV->getDeclName(); 2967 } else if (!IDecl->isSuperClassOf(ClassOfMethodDecl)) 2968 // @protected 2969 Diag(MemberLoc, diag::error_protected_ivar_access) 2970 << IV->getDeclName(); 2971 } 2972 2973 return Owned(new (Context) ObjCIvarRefExpr(IV, IV->getType(), 2974 MemberLoc, BaseExpr, 2975 IsArrow)); 2976 } 2977 return ExprError(Diag(MemberLoc, diag::err_typecheck_member_reference_ivar) 2978 << IDecl->getDeclName() << MemberName 2979 << BaseExpr->getSourceRange()); 2980 } 2981 } 2982 // Handle properties on 'id' and qualified "id". 2983 if (!IsArrow && (BaseType->isObjCIdType() || 2984 BaseType->isObjCQualifiedIdType())) { 2985 const ObjCObjectPointerType *QIdTy = BaseType->getAs<ObjCObjectPointerType>(); 2986 IdentifierInfo *Member = MemberName.getAsIdentifierInfo(); 2987 2988 // Check protocols on qualified interfaces. 2989 Selector Sel = PP.getSelectorTable().getNullarySelector(Member); 2990 if (Decl *PMDecl = FindGetterNameDecl(QIdTy, Member, Sel, Context)) { 2991 if (ObjCPropertyDecl *PD = dyn_cast<ObjCPropertyDecl>(PMDecl)) { 2992 // Check the use of this declaration 2993 if (DiagnoseUseOfDecl(PD, MemberLoc)) 2994 return ExprError(); 2995 2996 return Owned(new (Context) ObjCPropertyRefExpr(PD, PD->getType(), 2997 MemberLoc, BaseExpr)); 2998 } 2999 if (ObjCMethodDecl *OMD = dyn_cast<ObjCMethodDecl>(PMDecl)) { 3000 // Check the use of this method. 3001 if (DiagnoseUseOfDecl(OMD, MemberLoc)) 3002 return ExprError(); 3003 3004 return Owned(new (Context) ObjCMessageExpr(BaseExpr, Sel, 3005 OMD->getResultType(), 3006 OMD, OpLoc, MemberLoc, 3007 NULL, 0)); 3008 } 3009 } 3010 3011 return ExprError(Diag(MemberLoc, diag::err_property_not_found) 3012 << MemberName << BaseType); 3013 } 3014 // Handle Objective-C property access, which is "Obj.property" where Obj is a 3015 // pointer to a (potentially qualified) interface type. 3016 const ObjCObjectPointerType *OPT; 3017 if (!IsArrow && (OPT = BaseType->getAsObjCInterfacePointerType())) { 3018 const ObjCInterfaceType *IFaceT = OPT->getInterfaceType(); 3019 ObjCInterfaceDecl *IFace = IFaceT->getDecl(); 3020 IdentifierInfo *Member = MemberName.getAsIdentifierInfo(); 3021 3022 // Search for a declared property first. 3023 if (ObjCPropertyDecl *PD = IFace->FindPropertyDeclaration(Member)) { 3024 // Check whether we can reference this property. 3025 if (DiagnoseUseOfDecl(PD, MemberLoc)) 3026 return ExprError(); 3027 QualType ResTy = PD->getType(); 3028 Selector Sel = PP.getSelectorTable().getNullarySelector(Member); 3029 ObjCMethodDecl *Getter = IFace->lookupInstanceMethod(Sel); 3030 if (DiagnosePropertyAccessorMismatch(PD, Getter, MemberLoc)) 3031 ResTy = Getter->getResultType(); 3032 return Owned(new (Context) ObjCPropertyRefExpr(PD, ResTy, 3033 MemberLoc, BaseExpr)); 3034 } 3035 // Check protocols on qualified interfaces. 3036 for (ObjCObjectPointerType::qual_iterator I = OPT->qual_begin(), 3037 E = OPT->qual_end(); I != E; ++I) 3038 if (ObjCPropertyDecl *PD = (*I)->FindPropertyDeclaration(Member)) { 3039 // Check whether we can reference this property. 3040 if (DiagnoseUseOfDecl(PD, MemberLoc)) 3041 return ExprError(); 3042 3043 return Owned(new (Context) ObjCPropertyRefExpr(PD, PD->getType(), 3044 MemberLoc, BaseExpr)); 3045 } 3046 // If that failed, look for an "implicit" property by seeing if the nullary 3047 // selector is implemented. 3048 3049 // FIXME: The logic for looking up nullary and unary selectors should be 3050 // shared with the code in ActOnInstanceMessage. 3051 3052 Selector Sel = PP.getSelectorTable().getNullarySelector(Member); 3053 ObjCMethodDecl *Getter = IFace->lookupInstanceMethod(Sel); 3054 3055 // If this reference is in an @implementation, check for 'private' methods. 3056 if (!Getter) 3057 Getter = IFace->lookupPrivateInstanceMethod(Sel); 3058 3059 // Look through local category implementations associated with the class. 3060 if (!Getter) 3061 Getter = IFace->getCategoryInstanceMethod(Sel); 3062 if (Getter) { 3063 // Check if we can reference this property. 3064 if (DiagnoseUseOfDecl(Getter, MemberLoc)) 3065 return ExprError(); 3066 } 3067 // If we found a getter then this may be a valid dot-reference, we 3068 // will look for the matching setter, in case it is needed. 3069 Selector SetterSel = 3070 SelectorTable::constructSetterName(PP.getIdentifierTable(), 3071 PP.getSelectorTable(), Member); 3072 ObjCMethodDecl *Setter = IFace->lookupInstanceMethod(SetterSel); 3073 if (!Setter) { 3074 // If this reference is in an @implementation, also check for 'private' 3075 // methods. 3076 Setter = IFace->lookupPrivateInstanceMethod(SetterSel); 3077 } 3078 // Look through local category implementations associated with the class. 3079 if (!Setter) 3080 Setter = IFace->getCategoryInstanceMethod(SetterSel); 3081 3082 if (Setter && DiagnoseUseOfDecl(Setter, MemberLoc)) 3083 return ExprError(); 3084 3085 if (Getter) { 3086 QualType PType; 3087 PType = Getter->getResultType(); 3088 return Owned(new (Context) ObjCImplicitSetterGetterRefExpr(Getter, PType, 3089 Setter, MemberLoc, BaseExpr)); 3090 } 3091 3092 // Attempt to correct for typos in property names. 3093 LookupResult Res(*this, R.getLookupName(), R.getNameLoc(), 3094 LookupOrdinaryName); 3095 if (CorrectTypo(Res, 0, 0, IFace, false, OPT) && 3096 Res.getAsSingle<ObjCPropertyDecl>()) { 3097 Diag(R.getNameLoc(), diag::err_property_not_found_suggest) 3098 << MemberName << BaseType << Res.getLookupName() 3099 << CodeModificationHint::CreateReplacement(R.getNameLoc(), 3100 Res.getLookupName().getAsString()); 3101 ObjCPropertyDecl *Property = Res.getAsSingle<ObjCPropertyDecl>(); 3102 Diag(Property->getLocation(), diag::note_previous_decl) 3103 << Property->getDeclName(); 3104 3105 return LookupMemberExpr(Res, BaseExpr, IsArrow, OpLoc, SS, 3106 ObjCImpDecl); 3107 } 3108 3109 return ExprError(Diag(MemberLoc, diag::err_property_not_found) 3110 << MemberName << BaseType); 3111 } 3112 3113 // Handle the following exceptional case (*Obj).isa. 3114 if (!IsArrow && 3115 BaseType->isSpecificBuiltinType(BuiltinType::ObjCId) && 3116 MemberName.getAsIdentifierInfo()->isStr("isa")) 3117 return Owned(new (Context) ObjCIsaExpr(BaseExpr, false, MemberLoc, 3118 Context.getObjCClassType())); 3119 3120 // Handle 'field access' to vectors, such as 'V.xx'. 3121 if (BaseType->isExtVectorType()) { 3122 IdentifierInfo *Member = MemberName.getAsIdentifierInfo(); 3123 QualType ret = CheckExtVectorComponent(BaseType, OpLoc, Member, MemberLoc); 3124 if (ret.isNull()) 3125 return ExprError(); 3126 return Owned(new (Context) ExtVectorElementExpr(ret, BaseExpr, *Member, 3127 MemberLoc)); 3128 } 3129 3130 Diag(MemberLoc, diag::err_typecheck_member_reference_struct_union) 3131 << BaseType << BaseExpr->getSourceRange(); 3132 3133 return ExprError(); 3134} 3135 3136static Sema::OwningExprResult DiagnoseDtorReference(Sema &SemaRef, 3137 SourceLocation NameLoc, 3138 Sema::ExprArg MemExpr) { 3139 Expr *E = (Expr *) MemExpr.get(); 3140 SourceLocation ExpectedLParenLoc = SemaRef.PP.getLocForEndOfToken(NameLoc); 3141 SemaRef.Diag(E->getLocStart(), diag::err_dtor_expr_without_call) 3142 << isa<CXXPseudoDestructorExpr>(E) 3143 << CodeModificationHint::CreateInsertion(ExpectedLParenLoc, "()"); 3144 3145 return SemaRef.ActOnCallExpr(/*Scope*/ 0, 3146 move(MemExpr), 3147 /*LPLoc*/ ExpectedLParenLoc, 3148 Sema::MultiExprArg(SemaRef, 0, 0), 3149 /*CommaLocs*/ 0, 3150 /*RPLoc*/ ExpectedLParenLoc); 3151} 3152 3153/// The main callback when the parser finds something like 3154/// expression . [nested-name-specifier] identifier 3155/// expression -> [nested-name-specifier] identifier 3156/// where 'identifier' encompasses a fairly broad spectrum of 3157/// possibilities, including destructor and operator references. 3158/// 3159/// \param OpKind either tok::arrow or tok::period 3160/// \param HasTrailingLParen whether the next token is '(', which 3161/// is used to diagnose mis-uses of special members that can 3162/// only be called 3163/// \param ObjCImpDecl the current ObjC @implementation decl; 3164/// this is an ugly hack around the fact that ObjC @implementations 3165/// aren't properly put in the context chain 3166Sema::OwningExprResult Sema::ActOnMemberAccessExpr(Scope *S, ExprArg BaseArg, 3167 SourceLocation OpLoc, 3168 tok::TokenKind OpKind, 3169 const CXXScopeSpec &SS, 3170 UnqualifiedId &Id, 3171 DeclPtrTy ObjCImpDecl, 3172 bool HasTrailingLParen) { 3173 if (SS.isSet() && SS.isInvalid()) 3174 return ExprError(); 3175 3176 TemplateArgumentListInfo TemplateArgsBuffer; 3177 3178 // Decompose the name into its component parts. 3179 DeclarationName Name; 3180 SourceLocation NameLoc; 3181 const TemplateArgumentListInfo *TemplateArgs; 3182 DecomposeUnqualifiedId(*this, Id, TemplateArgsBuffer, 3183 Name, NameLoc, TemplateArgs); 3184 3185 bool IsArrow = (OpKind == tok::arrow); 3186 3187 NamedDecl *FirstQualifierInScope 3188 = (!SS.isSet() ? 0 : FindFirstQualifierInScope(S, 3189 static_cast<NestedNameSpecifier*>(SS.getScopeRep()))); 3190 3191 // This is a postfix expression, so get rid of ParenListExprs. 3192 BaseArg = MaybeConvertParenListExprToParenExpr(S, move(BaseArg)); 3193 3194 Expr *Base = BaseArg.takeAs<Expr>(); 3195 OwningExprResult Result(*this); 3196 if (Base->getType()->isDependentType() || Name.isDependentName()) { 3197 Result = ActOnDependentMemberExpr(ExprArg(*this, Base), Base->getType(), 3198 IsArrow, OpLoc, 3199 SS, FirstQualifierInScope, 3200 Name, NameLoc, 3201 TemplateArgs); 3202 } else { 3203 LookupResult R(*this, Name, NameLoc, LookupMemberName); 3204 if (TemplateArgs) { 3205 // Re-use the lookup done for the template name. 3206 DecomposeTemplateName(R, Id); 3207 } else { 3208 Result = LookupMemberExpr(R, Base, IsArrow, OpLoc, 3209 SS, ObjCImpDecl); 3210 3211 if (Result.isInvalid()) { 3212 Owned(Base); 3213 return ExprError(); 3214 } 3215 3216 if (Result.get()) { 3217 // The only way a reference to a destructor can be used is to 3218 // immediately call it, which falls into this case. If the 3219 // next token is not a '(', produce a diagnostic and build the 3220 // call now. 3221 if (!HasTrailingLParen && 3222 Id.getKind() == UnqualifiedId::IK_DestructorName) 3223 return DiagnoseDtorReference(*this, NameLoc, move(Result)); 3224 3225 return move(Result); 3226 } 3227 } 3228 3229 Result = BuildMemberReferenceExpr(ExprArg(*this, Base), Base->getType(), 3230 OpLoc, IsArrow, SS, FirstQualifierInScope, 3231 R, TemplateArgs); 3232 } 3233 3234 return move(Result); 3235} 3236 3237Sema::OwningExprResult Sema::BuildCXXDefaultArgExpr(SourceLocation CallLoc, 3238 FunctionDecl *FD, 3239 ParmVarDecl *Param) { 3240 if (Param->hasUnparsedDefaultArg()) { 3241 Diag (CallLoc, 3242 diag::err_use_of_default_argument_to_function_declared_later) << 3243 FD << cast<CXXRecordDecl>(FD->getDeclContext())->getDeclName(); 3244 Diag(UnparsedDefaultArgLocs[Param], 3245 diag::note_default_argument_declared_here); 3246 } else { 3247 if (Param->hasUninstantiatedDefaultArg()) { 3248 Expr *UninstExpr = Param->getUninstantiatedDefaultArg(); 3249 3250 // Instantiate the expression. 3251 MultiLevelTemplateArgumentList ArgList = getTemplateInstantiationArgs(FD); 3252 3253 InstantiatingTemplate Inst(*this, CallLoc, Param, 3254 ArgList.getInnermost().getFlatArgumentList(), 3255 ArgList.getInnermost().flat_size()); 3256 3257 OwningExprResult Result = SubstExpr(UninstExpr, ArgList); 3258 if (Result.isInvalid()) 3259 return ExprError(); 3260 3261 // Check the expression as an initializer for the parameter. 3262 InitializedEntity Entity 3263 = InitializedEntity::InitializeParameter(Param); 3264 InitializationKind Kind 3265 = InitializationKind::CreateCopy(Param->getLocation(), 3266 /*FIXME:EqualLoc*/UninstExpr->getSourceRange().getBegin()); 3267 Expr *ResultE = Result.takeAs<Expr>(); 3268 3269 InitializationSequence InitSeq(*this, Entity, Kind, &ResultE, 1); 3270 Result = InitSeq.Perform(*this, Entity, Kind, 3271 MultiExprArg(*this, (void**)&ResultE, 1)); 3272 if (Result.isInvalid()) 3273 return ExprError(); 3274 3275 // Build the default argument expression. 3276 return Owned(CXXDefaultArgExpr::Create(Context, CallLoc, Param, 3277 Result.takeAs<Expr>())); 3278 } 3279 3280 // If the default expression creates temporaries, we need to 3281 // push them to the current stack of expression temporaries so they'll 3282 // be properly destroyed. 3283 // FIXME: We should really be rebuilding the default argument with new 3284 // bound temporaries; see the comment in PR5810. 3285 for (unsigned i = 0, e = Param->getNumDefaultArgTemporaries(); i != e; ++i) 3286 ExprTemporaries.push_back(Param->getDefaultArgTemporary(i)); 3287 } 3288 3289 // We already type-checked the argument, so we know it works. 3290 return Owned(CXXDefaultArgExpr::Create(Context, CallLoc, Param)); 3291} 3292 3293/// ConvertArgumentsForCall - Converts the arguments specified in 3294/// Args/NumArgs to the parameter types of the function FDecl with 3295/// function prototype Proto. Call is the call expression itself, and 3296/// Fn is the function expression. For a C++ member function, this 3297/// routine does not attempt to convert the object argument. Returns 3298/// true if the call is ill-formed. 3299bool 3300Sema::ConvertArgumentsForCall(CallExpr *Call, Expr *Fn, 3301 FunctionDecl *FDecl, 3302 const FunctionProtoType *Proto, 3303 Expr **Args, unsigned NumArgs, 3304 SourceLocation RParenLoc) { 3305 // C99 6.5.2.2p7 - the arguments are implicitly converted, as if by 3306 // assignment, to the types of the corresponding parameter, ... 3307 unsigned NumArgsInProto = Proto->getNumArgs(); 3308 bool Invalid = false; 3309 3310 // If too few arguments are available (and we don't have default 3311 // arguments for the remaining parameters), don't make the call. 3312 if (NumArgs < NumArgsInProto) { 3313 if (!FDecl || NumArgs < FDecl->getMinRequiredArguments()) 3314 return Diag(RParenLoc, diag::err_typecheck_call_too_few_args) 3315 << Fn->getType()->isBlockPointerType() << Fn->getSourceRange(); 3316 Call->setNumArgs(Context, NumArgsInProto); 3317 } 3318 3319 // If too many are passed and not variadic, error on the extras and drop 3320 // them. 3321 if (NumArgs > NumArgsInProto) { 3322 if (!Proto->isVariadic()) { 3323 Diag(Args[NumArgsInProto]->getLocStart(), 3324 diag::err_typecheck_call_too_many_args) 3325 << Fn->getType()->isBlockPointerType() << Fn->getSourceRange() 3326 << SourceRange(Args[NumArgsInProto]->getLocStart(), 3327 Args[NumArgs-1]->getLocEnd()); 3328 // This deletes the extra arguments. 3329 Call->setNumArgs(Context, NumArgsInProto); 3330 return true; 3331 } 3332 } 3333 llvm::SmallVector<Expr *, 8> AllArgs; 3334 VariadicCallType CallType = 3335 Proto->isVariadic() ? VariadicFunction : VariadicDoesNotApply; 3336 if (Fn->getType()->isBlockPointerType()) 3337 CallType = VariadicBlock; // Block 3338 else if (isa<MemberExpr>(Fn)) 3339 CallType = VariadicMethod; 3340 Invalid = GatherArgumentsForCall(Call->getSourceRange().getBegin(), FDecl, 3341 Proto, 0, Args, NumArgs, AllArgs, CallType); 3342 if (Invalid) 3343 return true; 3344 unsigned TotalNumArgs = AllArgs.size(); 3345 for (unsigned i = 0; i < TotalNumArgs; ++i) 3346 Call->setArg(i, AllArgs[i]); 3347 3348 return false; 3349} 3350 3351bool Sema::GatherArgumentsForCall(SourceLocation CallLoc, 3352 FunctionDecl *FDecl, 3353 const FunctionProtoType *Proto, 3354 unsigned FirstProtoArg, 3355 Expr **Args, unsigned NumArgs, 3356 llvm::SmallVector<Expr *, 8> &AllArgs, 3357 VariadicCallType CallType) { 3358 unsigned NumArgsInProto = Proto->getNumArgs(); 3359 unsigned NumArgsToCheck = NumArgs; 3360 bool Invalid = false; 3361 if (NumArgs != NumArgsInProto) 3362 // Use default arguments for missing arguments 3363 NumArgsToCheck = NumArgsInProto; 3364 unsigned ArgIx = 0; 3365 // Continue to check argument types (even if we have too few/many args). 3366 for (unsigned i = FirstProtoArg; i != NumArgsToCheck; i++) { 3367 QualType ProtoArgType = Proto->getArgType(i); 3368 3369 Expr *Arg; 3370 if (ArgIx < NumArgs) { 3371 Arg = Args[ArgIx++]; 3372 3373 if (RequireCompleteType(Arg->getSourceRange().getBegin(), 3374 ProtoArgType, 3375 PDiag(diag::err_call_incomplete_argument) 3376 << Arg->getSourceRange())) 3377 return true; 3378 3379 // Pass the argument 3380 ParmVarDecl *Param = 0; 3381 if (FDecl && i < FDecl->getNumParams()) 3382 Param = FDecl->getParamDecl(i); 3383 3384 3385 InitializedEntity Entity = 3386 Param? InitializedEntity::InitializeParameter(Param) 3387 : InitializedEntity::InitializeParameter(ProtoArgType); 3388 OwningExprResult ArgE = PerformCopyInitialization(Entity, 3389 SourceLocation(), 3390 Owned(Arg)); 3391 if (ArgE.isInvalid()) 3392 return true; 3393 3394 Arg = ArgE.takeAs<Expr>(); 3395 } else { 3396 ParmVarDecl *Param = FDecl->getParamDecl(i); 3397 3398 OwningExprResult ArgExpr = 3399 BuildCXXDefaultArgExpr(CallLoc, FDecl, Param); 3400 if (ArgExpr.isInvalid()) 3401 return true; 3402 3403 Arg = ArgExpr.takeAs<Expr>(); 3404 } 3405 AllArgs.push_back(Arg); 3406 } 3407 3408 // If this is a variadic call, handle args passed through "...". 3409 if (CallType != VariadicDoesNotApply) { 3410 // Promote the arguments (C99 6.5.2.2p7). 3411 for (unsigned i = ArgIx; i < NumArgs; i++) { 3412 Expr *Arg = Args[i]; 3413 Invalid |= DefaultVariadicArgumentPromotion(Arg, CallType); 3414 AllArgs.push_back(Arg); 3415 } 3416 } 3417 return Invalid; 3418} 3419 3420/// ActOnCallExpr - Handle a call to Fn with the specified array of arguments. 3421/// This provides the location of the left/right parens and a list of comma 3422/// locations. 3423Action::OwningExprResult 3424Sema::ActOnCallExpr(Scope *S, ExprArg fn, SourceLocation LParenLoc, 3425 MultiExprArg args, 3426 SourceLocation *CommaLocs, SourceLocation RParenLoc) { 3427 unsigned NumArgs = args.size(); 3428 3429 // Since this might be a postfix expression, get rid of ParenListExprs. 3430 fn = MaybeConvertParenListExprToParenExpr(S, move(fn)); 3431 3432 Expr *Fn = fn.takeAs<Expr>(); 3433 Expr **Args = reinterpret_cast<Expr**>(args.release()); 3434 assert(Fn && "no function call expression"); 3435 3436 if (getLangOptions().CPlusPlus) { 3437 // If this is a pseudo-destructor expression, build the call immediately. 3438 if (isa<CXXPseudoDestructorExpr>(Fn)) { 3439 if (NumArgs > 0) { 3440 // Pseudo-destructor calls should not have any arguments. 3441 Diag(Fn->getLocStart(), diag::err_pseudo_dtor_call_with_args) 3442 << CodeModificationHint::CreateRemoval( 3443 SourceRange(Args[0]->getLocStart(), 3444 Args[NumArgs-1]->getLocEnd())); 3445 3446 for (unsigned I = 0; I != NumArgs; ++I) 3447 Args[I]->Destroy(Context); 3448 3449 NumArgs = 0; 3450 } 3451 3452 return Owned(new (Context) CallExpr(Context, Fn, 0, 0, Context.VoidTy, 3453 RParenLoc)); 3454 } 3455 3456 // Determine whether this is a dependent call inside a C++ template, 3457 // in which case we won't do any semantic analysis now. 3458 // FIXME: Will need to cache the results of name lookup (including ADL) in 3459 // Fn. 3460 bool Dependent = false; 3461 if (Fn->isTypeDependent()) 3462 Dependent = true; 3463 else if (Expr::hasAnyTypeDependentArguments(Args, NumArgs)) 3464 Dependent = true; 3465 3466 if (Dependent) 3467 return Owned(new (Context) CallExpr(Context, Fn, Args, NumArgs, 3468 Context.DependentTy, RParenLoc)); 3469 3470 // Determine whether this is a call to an object (C++ [over.call.object]). 3471 if (Fn->getType()->isRecordType()) 3472 return Owned(BuildCallToObjectOfClassType(S, Fn, LParenLoc, Args, NumArgs, 3473 CommaLocs, RParenLoc)); 3474 3475 Expr *NakedFn = Fn->IgnoreParens(); 3476 3477 // Determine whether this is a call to an unresolved member function. 3478 if (UnresolvedMemberExpr *MemE = dyn_cast<UnresolvedMemberExpr>(NakedFn)) { 3479 // If lookup was unresolved but not dependent (i.e. didn't find 3480 // an unresolved using declaration), it has to be an overloaded 3481 // function set, which means it must contain either multiple 3482 // declarations (all methods or method templates) or a single 3483 // method template. 3484 assert((MemE->getNumDecls() > 1) || 3485 isa<FunctionTemplateDecl>(*MemE->decls_begin())); 3486 (void)MemE; 3487 3488 return BuildCallToMemberFunction(S, Fn, LParenLoc, Args, NumArgs, 3489 CommaLocs, RParenLoc); 3490 } 3491 3492 // Determine whether this is a call to a member function. 3493 if (MemberExpr *MemExpr = dyn_cast<MemberExpr>(NakedFn)) { 3494 NamedDecl *MemDecl = MemExpr->getMemberDecl(); 3495 if (isa<CXXMethodDecl>(MemDecl)) 3496 return BuildCallToMemberFunction(S, Fn, LParenLoc, Args, NumArgs, 3497 CommaLocs, RParenLoc); 3498 } 3499 3500 // Determine whether this is a call to a pointer-to-member function. 3501 if (BinaryOperator *BO = dyn_cast<BinaryOperator>(NakedFn)) { 3502 if (BO->getOpcode() == BinaryOperator::PtrMemD || 3503 BO->getOpcode() == BinaryOperator::PtrMemI) { 3504 if (const FunctionProtoType *FPT = 3505 dyn_cast<FunctionProtoType>(BO->getType())) { 3506 QualType ResultTy = FPT->getResultType().getNonReferenceType(); 3507 3508 ExprOwningPtr<CXXMemberCallExpr> 3509 TheCall(this, new (Context) CXXMemberCallExpr(Context, BO, Args, 3510 NumArgs, ResultTy, 3511 RParenLoc)); 3512 3513 if (CheckCallReturnType(FPT->getResultType(), 3514 BO->getRHS()->getSourceRange().getBegin(), 3515 TheCall.get(), 0)) 3516 return ExprError(); 3517 3518 if (ConvertArgumentsForCall(&*TheCall, BO, 0, FPT, Args, NumArgs, 3519 RParenLoc)) 3520 return ExprError(); 3521 3522 return Owned(MaybeBindToTemporary(TheCall.release()).release()); 3523 } 3524 return ExprError(Diag(Fn->getLocStart(), 3525 diag::err_typecheck_call_not_function) 3526 << Fn->getType() << Fn->getSourceRange()); 3527 } 3528 } 3529 } 3530 3531 // If we're directly calling a function, get the appropriate declaration. 3532 // Also, in C++, keep track of whether we should perform argument-dependent 3533 // lookup and whether there were any explicitly-specified template arguments. 3534 3535 Expr *NakedFn = Fn->IgnoreParens(); 3536 if (isa<UnresolvedLookupExpr>(NakedFn)) { 3537 UnresolvedLookupExpr *ULE = cast<UnresolvedLookupExpr>(NakedFn); 3538 return BuildOverloadedCallExpr(Fn, ULE, LParenLoc, Args, NumArgs, 3539 CommaLocs, RParenLoc); 3540 } 3541 3542 NamedDecl *NDecl = 0; 3543 if (isa<DeclRefExpr>(NakedFn)) 3544 NDecl = cast<DeclRefExpr>(NakedFn)->getDecl(); 3545 3546 return BuildResolvedCallExpr(Fn, NDecl, LParenLoc, Args, NumArgs, RParenLoc); 3547} 3548 3549/// BuildResolvedCallExpr - Build a call to a resolved expression, 3550/// i.e. an expression not of \p OverloadTy. The expression should 3551/// unary-convert to an expression of function-pointer or 3552/// block-pointer type. 3553/// 3554/// \param NDecl the declaration being called, if available 3555Sema::OwningExprResult 3556Sema::BuildResolvedCallExpr(Expr *Fn, NamedDecl *NDecl, 3557 SourceLocation LParenLoc, 3558 Expr **Args, unsigned NumArgs, 3559 SourceLocation RParenLoc) { 3560 FunctionDecl *FDecl = dyn_cast_or_null<FunctionDecl>(NDecl); 3561 3562 // Promote the function operand. 3563 UsualUnaryConversions(Fn); 3564 3565 // Make the call expr early, before semantic checks. This guarantees cleanup 3566 // of arguments and function on error. 3567 ExprOwningPtr<CallExpr> TheCall(this, new (Context) CallExpr(Context, Fn, 3568 Args, NumArgs, 3569 Context.BoolTy, 3570 RParenLoc)); 3571 3572 const FunctionType *FuncT; 3573 if (!Fn->getType()->isBlockPointerType()) { 3574 // C99 6.5.2.2p1 - "The expression that denotes the called function shall 3575 // have type pointer to function". 3576 const PointerType *PT = Fn->getType()->getAs<PointerType>(); 3577 if (PT == 0) 3578 return ExprError(Diag(LParenLoc, diag::err_typecheck_call_not_function) 3579 << Fn->getType() << Fn->getSourceRange()); 3580 FuncT = PT->getPointeeType()->getAs<FunctionType>(); 3581 } else { // This is a block call. 3582 FuncT = Fn->getType()->getAs<BlockPointerType>()->getPointeeType()-> 3583 getAs<FunctionType>(); 3584 } 3585 if (FuncT == 0) 3586 return ExprError(Diag(LParenLoc, diag::err_typecheck_call_not_function) 3587 << Fn->getType() << Fn->getSourceRange()); 3588 3589 // Check for a valid return type 3590 if (CheckCallReturnType(FuncT->getResultType(), 3591 Fn->getSourceRange().getBegin(), TheCall.get(), 3592 FDecl)) 3593 return ExprError(); 3594 3595 // We know the result type of the call, set it. 3596 TheCall->setType(FuncT->getResultType().getNonReferenceType()); 3597 3598 if (const FunctionProtoType *Proto = dyn_cast<FunctionProtoType>(FuncT)) { 3599 if (ConvertArgumentsForCall(&*TheCall, Fn, FDecl, Proto, Args, NumArgs, 3600 RParenLoc)) 3601 return ExprError(); 3602 } else { 3603 assert(isa<FunctionNoProtoType>(FuncT) && "Unknown FunctionType!"); 3604 3605 if (FDecl) { 3606 // Check if we have too few/too many template arguments, based 3607 // on our knowledge of the function definition. 3608 const FunctionDecl *Def = 0; 3609 if (FDecl->getBody(Def) && NumArgs != Def->param_size()) { 3610 const FunctionProtoType *Proto = 3611 Def->getType()->getAs<FunctionProtoType>(); 3612 if (!Proto || !(Proto->isVariadic() && NumArgs >= Def->param_size())) { 3613 Diag(RParenLoc, diag::warn_call_wrong_number_of_arguments) 3614 << (NumArgs > Def->param_size()) << FDecl << Fn->getSourceRange(); 3615 } 3616 } 3617 } 3618 3619 // Promote the arguments (C99 6.5.2.2p6). 3620 for (unsigned i = 0; i != NumArgs; i++) { 3621 Expr *Arg = Args[i]; 3622 DefaultArgumentPromotion(Arg); 3623 if (RequireCompleteType(Arg->getSourceRange().getBegin(), 3624 Arg->getType(), 3625 PDiag(diag::err_call_incomplete_argument) 3626 << Arg->getSourceRange())) 3627 return ExprError(); 3628 TheCall->setArg(i, Arg); 3629 } 3630 } 3631 3632 if (CXXMethodDecl *Method = dyn_cast_or_null<CXXMethodDecl>(FDecl)) 3633 if (!Method->isStatic()) 3634 return ExprError(Diag(LParenLoc, diag::err_member_call_without_object) 3635 << Fn->getSourceRange()); 3636 3637 // Check for sentinels 3638 if (NDecl) 3639 DiagnoseSentinelCalls(NDecl, LParenLoc, Args, NumArgs); 3640 3641 // Do special checking on direct calls to functions. 3642 if (FDecl) { 3643 if (CheckFunctionCall(FDecl, TheCall.get())) 3644 return ExprError(); 3645 3646 if (unsigned BuiltinID = FDecl->getBuiltinID()) 3647 return CheckBuiltinFunctionCall(BuiltinID, TheCall.take()); 3648 } else if (NDecl) { 3649 if (CheckBlockCall(NDecl, TheCall.get())) 3650 return ExprError(); 3651 } 3652 3653 return MaybeBindToTemporary(TheCall.take()); 3654} 3655 3656Action::OwningExprResult 3657Sema::ActOnCompoundLiteral(SourceLocation LParenLoc, TypeTy *Ty, 3658 SourceLocation RParenLoc, ExprArg InitExpr) { 3659 assert((Ty != 0) && "ActOnCompoundLiteral(): missing type"); 3660 // FIXME: put back this assert when initializers are worked out. 3661 //assert((InitExpr != 0) && "ActOnCompoundLiteral(): missing expression"); 3662 3663 TypeSourceInfo *TInfo; 3664 QualType literalType = GetTypeFromParser(Ty, &TInfo); 3665 if (!TInfo) 3666 TInfo = Context.getTrivialTypeSourceInfo(literalType); 3667 3668 return BuildCompoundLiteralExpr(LParenLoc, TInfo, RParenLoc, move(InitExpr)); 3669} 3670 3671Action::OwningExprResult 3672Sema::BuildCompoundLiteralExpr(SourceLocation LParenLoc, TypeSourceInfo *TInfo, 3673 SourceLocation RParenLoc, ExprArg InitExpr) { 3674 QualType literalType = TInfo->getType(); 3675 Expr *literalExpr = static_cast<Expr*>(InitExpr.get()); 3676 3677 if (literalType->isArrayType()) { 3678 if (literalType->isVariableArrayType()) 3679 return ExprError(Diag(LParenLoc, diag::err_variable_object_no_init) 3680 << SourceRange(LParenLoc, literalExpr->getSourceRange().getEnd())); 3681 } else if (!literalType->isDependentType() && 3682 RequireCompleteType(LParenLoc, literalType, 3683 PDiag(diag::err_typecheck_decl_incomplete_type) 3684 << SourceRange(LParenLoc, 3685 literalExpr->getSourceRange().getEnd()))) 3686 return ExprError(); 3687 3688 InitializedEntity Entity 3689 = InitializedEntity::InitializeTemporary(literalType); 3690 InitializationKind Kind 3691 = InitializationKind::CreateCast(SourceRange(LParenLoc, RParenLoc), 3692 /*IsCStyleCast=*/true); 3693 InitializationSequence InitSeq(*this, Entity, Kind, &literalExpr, 1); 3694 OwningExprResult Result = InitSeq.Perform(*this, Entity, Kind, 3695 MultiExprArg(*this, (void**)&literalExpr, 1), 3696 &literalType); 3697 if (Result.isInvalid()) 3698 return ExprError(); 3699 InitExpr.release(); 3700 literalExpr = static_cast<Expr*>(Result.get()); 3701 3702 bool isFileScope = getCurFunctionOrMethodDecl() == 0; 3703 if (isFileScope) { // 6.5.2.5p3 3704 if (CheckForConstantInitializer(literalExpr, literalType)) 3705 return ExprError(); 3706 } 3707 3708 Result.release(); 3709 3710 return Owned(new (Context) CompoundLiteralExpr(LParenLoc, TInfo, literalType, 3711 literalExpr, isFileScope)); 3712} 3713 3714Action::OwningExprResult 3715Sema::ActOnInitList(SourceLocation LBraceLoc, MultiExprArg initlist, 3716 SourceLocation RBraceLoc) { 3717 unsigned NumInit = initlist.size(); 3718 Expr **InitList = reinterpret_cast<Expr**>(initlist.release()); 3719 3720 // Semantic analysis for initializers is done by ActOnDeclarator() and 3721 // CheckInitializer() - it requires knowledge of the object being intialized. 3722 3723 InitListExpr *E = new (Context) InitListExpr(LBraceLoc, InitList, NumInit, 3724 RBraceLoc); 3725 E->setType(Context.VoidTy); // FIXME: just a place holder for now. 3726 return Owned(E); 3727} 3728 3729static CastExpr::CastKind getScalarCastKind(ASTContext &Context, 3730 QualType SrcTy, QualType DestTy) { 3731 if (Context.hasSameUnqualifiedType(SrcTy, DestTy)) 3732 return CastExpr::CK_NoOp; 3733 3734 if (SrcTy->hasPointerRepresentation()) { 3735 if (DestTy->hasPointerRepresentation()) 3736 return DestTy->isObjCObjectPointerType() ? 3737 CastExpr::CK_AnyPointerToObjCPointerCast : 3738 CastExpr::CK_BitCast; 3739 if (DestTy->isIntegerType()) 3740 return CastExpr::CK_PointerToIntegral; 3741 } 3742 3743 if (SrcTy->isIntegerType()) { 3744 if (DestTy->isIntegerType()) 3745 return CastExpr::CK_IntegralCast; 3746 if (DestTy->hasPointerRepresentation()) 3747 return CastExpr::CK_IntegralToPointer; 3748 if (DestTy->isRealFloatingType()) 3749 return CastExpr::CK_IntegralToFloating; 3750 } 3751 3752 if (SrcTy->isRealFloatingType()) { 3753 if (DestTy->isRealFloatingType()) 3754 return CastExpr::CK_FloatingCast; 3755 if (DestTy->isIntegerType()) 3756 return CastExpr::CK_FloatingToIntegral; 3757 } 3758 3759 // FIXME: Assert here. 3760 // assert(false && "Unhandled cast combination!"); 3761 return CastExpr::CK_Unknown; 3762} 3763 3764/// CheckCastTypes - Check type constraints for casting between types. 3765bool Sema::CheckCastTypes(SourceRange TyR, QualType castType, Expr *&castExpr, 3766 CastExpr::CastKind& Kind, 3767 CXXMethodDecl *& ConversionDecl, 3768 bool FunctionalStyle) { 3769 if (getLangOptions().CPlusPlus) 3770 return CXXCheckCStyleCast(TyR, castType, castExpr, Kind, FunctionalStyle, 3771 ConversionDecl); 3772 3773 DefaultFunctionArrayConversion(castExpr); 3774 3775 // C99 6.5.4p2: the cast type needs to be void or scalar and the expression 3776 // type needs to be scalar. 3777 if (castType->isVoidType()) { 3778 // Cast to void allows any expr type. 3779 Kind = CastExpr::CK_ToVoid; 3780 return false; 3781 } 3782 3783 if (!castType->isScalarType() && !castType->isVectorType()) { 3784 if (Context.hasSameUnqualifiedType(castType, castExpr->getType()) && 3785 (castType->isStructureType() || castType->isUnionType())) { 3786 // GCC struct/union extension: allow cast to self. 3787 // FIXME: Check that the cast destination type is complete. 3788 Diag(TyR.getBegin(), diag::ext_typecheck_cast_nonscalar) 3789 << castType << castExpr->getSourceRange(); 3790 Kind = CastExpr::CK_NoOp; 3791 return false; 3792 } 3793 3794 if (castType->isUnionType()) { 3795 // GCC cast to union extension 3796 RecordDecl *RD = castType->getAs<RecordType>()->getDecl(); 3797 RecordDecl::field_iterator Field, FieldEnd; 3798 for (Field = RD->field_begin(), FieldEnd = RD->field_end(); 3799 Field != FieldEnd; ++Field) { 3800 if (Context.hasSameUnqualifiedType(Field->getType(), 3801 castExpr->getType())) { 3802 Diag(TyR.getBegin(), diag::ext_typecheck_cast_to_union) 3803 << castExpr->getSourceRange(); 3804 break; 3805 } 3806 } 3807 if (Field == FieldEnd) 3808 return Diag(TyR.getBegin(), diag::err_typecheck_cast_to_union_no_type) 3809 << castExpr->getType() << castExpr->getSourceRange(); 3810 Kind = CastExpr::CK_ToUnion; 3811 return false; 3812 } 3813 3814 // Reject any other conversions to non-scalar types. 3815 return Diag(TyR.getBegin(), diag::err_typecheck_cond_expect_scalar) 3816 << castType << castExpr->getSourceRange(); 3817 } 3818 3819 if (!castExpr->getType()->isScalarType() && 3820 !castExpr->getType()->isVectorType()) { 3821 return Diag(castExpr->getLocStart(), 3822 diag::err_typecheck_expect_scalar_operand) 3823 << castExpr->getType() << castExpr->getSourceRange(); 3824 } 3825 3826 if (castType->isExtVectorType()) 3827 return CheckExtVectorCast(TyR, castType, castExpr, Kind); 3828 3829 if (castType->isVectorType()) 3830 return CheckVectorCast(TyR, castType, castExpr->getType(), Kind); 3831 if (castExpr->getType()->isVectorType()) 3832 return CheckVectorCast(TyR, castExpr->getType(), castType, Kind); 3833 3834 if (getLangOptions().ObjC1 && isa<ObjCSuperExpr>(castExpr)) 3835 return Diag(castExpr->getLocStart(), diag::err_illegal_super_cast) << TyR; 3836 3837 if (isa<ObjCSelectorExpr>(castExpr)) 3838 return Diag(castExpr->getLocStart(), diag::err_cast_selector_expr); 3839 3840 if (!castType->isArithmeticType()) { 3841 QualType castExprType = castExpr->getType(); 3842 if (!castExprType->isIntegralType() && castExprType->isArithmeticType()) 3843 return Diag(castExpr->getLocStart(), 3844 diag::err_cast_pointer_from_non_pointer_int) 3845 << castExprType << castExpr->getSourceRange(); 3846 } else if (!castExpr->getType()->isArithmeticType()) { 3847 if (!castType->isIntegralType() && castType->isArithmeticType()) 3848 return Diag(castExpr->getLocStart(), 3849 diag::err_cast_pointer_to_non_pointer_int) 3850 << castType << castExpr->getSourceRange(); 3851 } 3852 3853 Kind = getScalarCastKind(Context, castExpr->getType(), castType); 3854 return false; 3855} 3856 3857bool Sema::CheckVectorCast(SourceRange R, QualType VectorTy, QualType Ty, 3858 CastExpr::CastKind &Kind) { 3859 assert(VectorTy->isVectorType() && "Not a vector type!"); 3860 3861 if (Ty->isVectorType() || Ty->isIntegerType()) { 3862 if (Context.getTypeSize(VectorTy) != Context.getTypeSize(Ty)) 3863 return Diag(R.getBegin(), 3864 Ty->isVectorType() ? 3865 diag::err_invalid_conversion_between_vectors : 3866 diag::err_invalid_conversion_between_vector_and_integer) 3867 << VectorTy << Ty << R; 3868 } else 3869 return Diag(R.getBegin(), 3870 diag::err_invalid_conversion_between_vector_and_scalar) 3871 << VectorTy << Ty << R; 3872 3873 Kind = CastExpr::CK_BitCast; 3874 return false; 3875} 3876 3877bool Sema::CheckExtVectorCast(SourceRange R, QualType DestTy, Expr *&CastExpr, 3878 CastExpr::CastKind &Kind) { 3879 assert(DestTy->isExtVectorType() && "Not an extended vector type!"); 3880 3881 QualType SrcTy = CastExpr->getType(); 3882 3883 // If SrcTy is a VectorType, the total size must match to explicitly cast to 3884 // an ExtVectorType. 3885 if (SrcTy->isVectorType()) { 3886 if (Context.getTypeSize(DestTy) != Context.getTypeSize(SrcTy)) 3887 return Diag(R.getBegin(),diag::err_invalid_conversion_between_ext_vectors) 3888 << DestTy << SrcTy << R; 3889 Kind = CastExpr::CK_BitCast; 3890 return false; 3891 } 3892 3893 // All non-pointer scalars can be cast to ExtVector type. The appropriate 3894 // conversion will take place first from scalar to elt type, and then 3895 // splat from elt type to vector. 3896 if (SrcTy->isPointerType()) 3897 return Diag(R.getBegin(), 3898 diag::err_invalid_conversion_between_vector_and_scalar) 3899 << DestTy << SrcTy << R; 3900 3901 QualType DestElemTy = DestTy->getAs<ExtVectorType>()->getElementType(); 3902 ImpCastExprToType(CastExpr, DestElemTy, 3903 getScalarCastKind(Context, SrcTy, DestElemTy)); 3904 3905 Kind = CastExpr::CK_VectorSplat; 3906 return false; 3907} 3908 3909Action::OwningExprResult 3910Sema::ActOnCastExpr(Scope *S, SourceLocation LParenLoc, TypeTy *Ty, 3911 SourceLocation RParenLoc, ExprArg Op) { 3912 assert((Ty != 0) && (Op.get() != 0) && 3913 "ActOnCastExpr(): missing type or expr"); 3914 3915 TypeSourceInfo *castTInfo; 3916 QualType castType = GetTypeFromParser(Ty, &castTInfo); 3917 if (!castTInfo) 3918 castTInfo = Context.getTrivialTypeSourceInfo(castType); 3919 3920 // If the Expr being casted is a ParenListExpr, handle it specially. 3921 Expr *castExpr = (Expr *)Op.get(); 3922 if (isa<ParenListExpr>(castExpr)) 3923 return ActOnCastOfParenListExpr(S, LParenLoc, RParenLoc, move(Op), 3924 castTInfo); 3925 3926 return BuildCStyleCastExpr(LParenLoc, castTInfo, RParenLoc, move(Op)); 3927} 3928 3929Action::OwningExprResult 3930Sema::BuildCStyleCastExpr(SourceLocation LParenLoc, TypeSourceInfo *Ty, 3931 SourceLocation RParenLoc, ExprArg Op) { 3932 Expr *castExpr = static_cast<Expr*>(Op.get()); 3933 3934 CXXMethodDecl *Method = 0; 3935 CastExpr::CastKind Kind = CastExpr::CK_Unknown; 3936 if (CheckCastTypes(SourceRange(LParenLoc, RParenLoc), Ty->getType(), castExpr, 3937 Kind, Method)) 3938 return ExprError(); 3939 3940 if (Method) { 3941 // FIXME: preserve type source info here 3942 OwningExprResult CastArg = BuildCXXCastArgument(LParenLoc, Ty->getType(), 3943 Kind, Method, move(Op)); 3944 3945 if (CastArg.isInvalid()) 3946 return ExprError(); 3947 3948 castExpr = CastArg.takeAs<Expr>(); 3949 } else { 3950 Op.release(); 3951 } 3952 3953 return Owned(new (Context) CStyleCastExpr(Ty->getType().getNonReferenceType(), 3954 Kind, castExpr, Ty, 3955 LParenLoc, RParenLoc)); 3956} 3957 3958/// This is not an AltiVec-style cast, so turn the ParenListExpr into a sequence 3959/// of comma binary operators. 3960Action::OwningExprResult 3961Sema::MaybeConvertParenListExprToParenExpr(Scope *S, ExprArg EA) { 3962 Expr *expr = EA.takeAs<Expr>(); 3963 ParenListExpr *E = dyn_cast<ParenListExpr>(expr); 3964 if (!E) 3965 return Owned(expr); 3966 3967 OwningExprResult Result(*this, E->getExpr(0)); 3968 3969 for (unsigned i = 1, e = E->getNumExprs(); i != e && !Result.isInvalid(); ++i) 3970 Result = ActOnBinOp(S, E->getExprLoc(), tok::comma, move(Result), 3971 Owned(E->getExpr(i))); 3972 3973 return ActOnParenExpr(E->getLParenLoc(), E->getRParenLoc(), move(Result)); 3974} 3975 3976Action::OwningExprResult 3977Sema::ActOnCastOfParenListExpr(Scope *S, SourceLocation LParenLoc, 3978 SourceLocation RParenLoc, ExprArg Op, 3979 TypeSourceInfo *TInfo) { 3980 ParenListExpr *PE = (ParenListExpr *)Op.get(); 3981 QualType Ty = TInfo->getType(); 3982 3983 // If this is an altivec initializer, '(' type ')' '(' init, ..., init ')' 3984 // then handle it as such. 3985 if (getLangOptions().AltiVec && Ty->isVectorType()) { 3986 if (PE->getNumExprs() == 0) { 3987 Diag(PE->getExprLoc(), diag::err_altivec_empty_initializer); 3988 return ExprError(); 3989 } 3990 3991 llvm::SmallVector<Expr *, 8> initExprs; 3992 for (unsigned i = 0, e = PE->getNumExprs(); i != e; ++i) 3993 initExprs.push_back(PE->getExpr(i)); 3994 3995 // FIXME: This means that pretty-printing the final AST will produce curly 3996 // braces instead of the original commas. 3997 Op.release(); 3998 InitListExpr *E = new (Context) InitListExpr(LParenLoc, &initExprs[0], 3999 initExprs.size(), RParenLoc); 4000 E->setType(Ty); 4001 return BuildCompoundLiteralExpr(LParenLoc, TInfo, RParenLoc, Owned(E)); 4002 } else { 4003 // This is not an AltiVec-style cast, so turn the ParenListExpr into a 4004 // sequence of BinOp comma operators. 4005 Op = MaybeConvertParenListExprToParenExpr(S, move(Op)); 4006 return BuildCStyleCastExpr(LParenLoc, TInfo, RParenLoc, move(Op)); 4007 } 4008} 4009 4010Action::OwningExprResult Sema::ActOnParenOrParenListExpr(SourceLocation L, 4011 SourceLocation R, 4012 MultiExprArg Val, 4013 TypeTy *TypeOfCast) { 4014 unsigned nexprs = Val.size(); 4015 Expr **exprs = reinterpret_cast<Expr**>(Val.release()); 4016 assert((exprs != 0) && "ActOnParenOrParenListExpr() missing expr list"); 4017 Expr *expr; 4018 if (nexprs == 1 && TypeOfCast && !TypeIsVectorType(TypeOfCast)) 4019 expr = new (Context) ParenExpr(L, R, exprs[0]); 4020 else 4021 expr = new (Context) ParenListExpr(Context, L, exprs, nexprs, R); 4022 return Owned(expr); 4023} 4024 4025/// Note that lhs is not null here, even if this is the gnu "x ?: y" extension. 4026/// In that case, lhs = cond. 4027/// C99 6.5.15 4028QualType Sema::CheckConditionalOperands(Expr *&Cond, Expr *&LHS, Expr *&RHS, 4029 SourceLocation QuestionLoc) { 4030 // C++ is sufficiently different to merit its own checker. 4031 if (getLangOptions().CPlusPlus) 4032 return CXXCheckConditionalOperands(Cond, LHS, RHS, QuestionLoc); 4033 4034 CheckSignCompare(LHS, RHS, QuestionLoc, diag::warn_mixed_sign_conditional); 4035 4036 UsualUnaryConversions(Cond); 4037 UsualUnaryConversions(LHS); 4038 UsualUnaryConversions(RHS); 4039 QualType CondTy = Cond->getType(); 4040 QualType LHSTy = LHS->getType(); 4041 QualType RHSTy = RHS->getType(); 4042 4043 // first, check the condition. 4044 if (!CondTy->isScalarType()) { // C99 6.5.15p2 4045 Diag(Cond->getLocStart(), diag::err_typecheck_cond_expect_scalar) 4046 << CondTy; 4047 return QualType(); 4048 } 4049 4050 // Now check the two expressions. 4051 if (LHSTy->isVectorType() || RHSTy->isVectorType()) 4052 return CheckVectorOperands(QuestionLoc, LHS, RHS); 4053 4054 // If both operands have arithmetic type, do the usual arithmetic conversions 4055 // to find a common type: C99 6.5.15p3,5. 4056 if (LHSTy->isArithmeticType() && RHSTy->isArithmeticType()) { 4057 UsualArithmeticConversions(LHS, RHS); 4058 return LHS->getType(); 4059 } 4060 4061 // If both operands are the same structure or union type, the result is that 4062 // type. 4063 if (const RecordType *LHSRT = LHSTy->getAs<RecordType>()) { // C99 6.5.15p3 4064 if (const RecordType *RHSRT = RHSTy->getAs<RecordType>()) 4065 if (LHSRT->getDecl() == RHSRT->getDecl()) 4066 // "If both the operands have structure or union type, the result has 4067 // that type." This implies that CV qualifiers are dropped. 4068 return LHSTy.getUnqualifiedType(); 4069 // FIXME: Type of conditional expression must be complete in C mode. 4070 } 4071 4072 // C99 6.5.15p5: "If both operands have void type, the result has void type." 4073 // The following || allows only one side to be void (a GCC-ism). 4074 if (LHSTy->isVoidType() || RHSTy->isVoidType()) { 4075 if (!LHSTy->isVoidType()) 4076 Diag(RHS->getLocStart(), diag::ext_typecheck_cond_one_void) 4077 << RHS->getSourceRange(); 4078 if (!RHSTy->isVoidType()) 4079 Diag(LHS->getLocStart(), diag::ext_typecheck_cond_one_void) 4080 << LHS->getSourceRange(); 4081 ImpCastExprToType(LHS, Context.VoidTy, CastExpr::CK_ToVoid); 4082 ImpCastExprToType(RHS, Context.VoidTy, CastExpr::CK_ToVoid); 4083 return Context.VoidTy; 4084 } 4085 // C99 6.5.15p6 - "if one operand is a null pointer constant, the result has 4086 // the type of the other operand." 4087 if ((LHSTy->isAnyPointerType() || LHSTy->isBlockPointerType()) && 4088 RHS->isNullPointerConstant(Context, Expr::NPC_ValueDependentIsNull)) { 4089 // promote the null to a pointer. 4090 ImpCastExprToType(RHS, LHSTy, CastExpr::CK_Unknown); 4091 return LHSTy; 4092 } 4093 if ((RHSTy->isAnyPointerType() || RHSTy->isBlockPointerType()) && 4094 LHS->isNullPointerConstant(Context, Expr::NPC_ValueDependentIsNull)) { 4095 ImpCastExprToType(LHS, RHSTy, CastExpr::CK_Unknown); 4096 return RHSTy; 4097 } 4098 4099 // All objective-c pointer type analysis is done here. 4100 QualType compositeType = FindCompositeObjCPointerType(LHS, RHS, 4101 QuestionLoc); 4102 if (!compositeType.isNull()) 4103 return compositeType; 4104 4105 4106 // Handle block pointer types. 4107 if (LHSTy->isBlockPointerType() || RHSTy->isBlockPointerType()) { 4108 if (!LHSTy->isBlockPointerType() || !RHSTy->isBlockPointerType()) { 4109 if (LHSTy->isVoidPointerType() || RHSTy->isVoidPointerType()) { 4110 QualType destType = Context.getPointerType(Context.VoidTy); 4111 ImpCastExprToType(LHS, destType, CastExpr::CK_BitCast); 4112 ImpCastExprToType(RHS, destType, CastExpr::CK_BitCast); 4113 return destType; 4114 } 4115 Diag(QuestionLoc, diag::err_typecheck_cond_incompatible_operands) 4116 << LHSTy << RHSTy << LHS->getSourceRange() << RHS->getSourceRange(); 4117 return QualType(); 4118 } 4119 // We have 2 block pointer types. 4120 if (Context.getCanonicalType(LHSTy) == Context.getCanonicalType(RHSTy)) { 4121 // Two identical block pointer types are always compatible. 4122 return LHSTy; 4123 } 4124 // The block pointer types aren't identical, continue checking. 4125 QualType lhptee = LHSTy->getAs<BlockPointerType>()->getPointeeType(); 4126 QualType rhptee = RHSTy->getAs<BlockPointerType>()->getPointeeType(); 4127 4128 if (!Context.typesAreCompatible(lhptee.getUnqualifiedType(), 4129 rhptee.getUnqualifiedType())) { 4130 Diag(QuestionLoc, diag::warn_typecheck_cond_incompatible_pointers) 4131 << LHSTy << RHSTy << LHS->getSourceRange() << RHS->getSourceRange(); 4132 // In this situation, we assume void* type. No especially good 4133 // reason, but this is what gcc does, and we do have to pick 4134 // to get a consistent AST. 4135 QualType incompatTy = Context.getPointerType(Context.VoidTy); 4136 ImpCastExprToType(LHS, incompatTy, CastExpr::CK_BitCast); 4137 ImpCastExprToType(RHS, incompatTy, CastExpr::CK_BitCast); 4138 return incompatTy; 4139 } 4140 // The block pointer types are compatible. 4141 ImpCastExprToType(LHS, LHSTy, CastExpr::CK_BitCast); 4142 ImpCastExprToType(RHS, LHSTy, CastExpr::CK_BitCast); 4143 return LHSTy; 4144 } 4145 4146 // Check constraints for C object pointers types (C99 6.5.15p3,6). 4147 if (LHSTy->isPointerType() && RHSTy->isPointerType()) { 4148 // get the "pointed to" types 4149 QualType lhptee = LHSTy->getAs<PointerType>()->getPointeeType(); 4150 QualType rhptee = RHSTy->getAs<PointerType>()->getPointeeType(); 4151 4152 // ignore qualifiers on void (C99 6.5.15p3, clause 6) 4153 if (lhptee->isVoidType() && rhptee->isIncompleteOrObjectType()) { 4154 // Figure out necessary qualifiers (C99 6.5.15p6) 4155 QualType destPointee 4156 = Context.getQualifiedType(lhptee, rhptee.getQualifiers()); 4157 QualType destType = Context.getPointerType(destPointee); 4158 // Add qualifiers if necessary. 4159 ImpCastExprToType(LHS, destType, CastExpr::CK_NoOp); 4160 // Promote to void*. 4161 ImpCastExprToType(RHS, destType, CastExpr::CK_BitCast); 4162 return destType; 4163 } 4164 if (rhptee->isVoidType() && lhptee->isIncompleteOrObjectType()) { 4165 QualType destPointee 4166 = Context.getQualifiedType(rhptee, lhptee.getQualifiers()); 4167 QualType destType = Context.getPointerType(destPointee); 4168 // Add qualifiers if necessary. 4169 ImpCastExprToType(RHS, destType, CastExpr::CK_NoOp); 4170 // Promote to void*. 4171 ImpCastExprToType(LHS, destType, CastExpr::CK_BitCast); 4172 return destType; 4173 } 4174 4175 if (Context.getCanonicalType(LHSTy) == Context.getCanonicalType(RHSTy)) { 4176 // Two identical pointer types are always compatible. 4177 return LHSTy; 4178 } 4179 if (!Context.typesAreCompatible(lhptee.getUnqualifiedType(), 4180 rhptee.getUnqualifiedType())) { 4181 Diag(QuestionLoc, diag::warn_typecheck_cond_incompatible_pointers) 4182 << LHSTy << RHSTy << LHS->getSourceRange() << RHS->getSourceRange(); 4183 // In this situation, we assume void* type. No especially good 4184 // reason, but this is what gcc does, and we do have to pick 4185 // to get a consistent AST. 4186 QualType incompatTy = Context.getPointerType(Context.VoidTy); 4187 ImpCastExprToType(LHS, incompatTy, CastExpr::CK_BitCast); 4188 ImpCastExprToType(RHS, incompatTy, CastExpr::CK_BitCast); 4189 return incompatTy; 4190 } 4191 // The pointer types are compatible. 4192 // C99 6.5.15p6: If both operands are pointers to compatible types *or* to 4193 // differently qualified versions of compatible types, the result type is 4194 // a pointer to an appropriately qualified version of the *composite* 4195 // type. 4196 // FIXME: Need to calculate the composite type. 4197 // FIXME: Need to add qualifiers 4198 ImpCastExprToType(LHS, LHSTy, CastExpr::CK_BitCast); 4199 ImpCastExprToType(RHS, LHSTy, CastExpr::CK_BitCast); 4200 return LHSTy; 4201 } 4202 4203 // GCC compatibility: soften pointer/integer mismatch. 4204 if (RHSTy->isPointerType() && LHSTy->isIntegerType()) { 4205 Diag(QuestionLoc, diag::warn_typecheck_cond_pointer_integer_mismatch) 4206 << LHSTy << RHSTy << LHS->getSourceRange() << RHS->getSourceRange(); 4207 ImpCastExprToType(LHS, RHSTy, CastExpr::CK_IntegralToPointer); 4208 return RHSTy; 4209 } 4210 if (LHSTy->isPointerType() && RHSTy->isIntegerType()) { 4211 Diag(QuestionLoc, diag::warn_typecheck_cond_pointer_integer_mismatch) 4212 << LHSTy << RHSTy << LHS->getSourceRange() << RHS->getSourceRange(); 4213 ImpCastExprToType(RHS, LHSTy, CastExpr::CK_IntegralToPointer); 4214 return LHSTy; 4215 } 4216 4217 // Otherwise, the operands are not compatible. 4218 Diag(QuestionLoc, diag::err_typecheck_cond_incompatible_operands) 4219 << LHSTy << RHSTy << LHS->getSourceRange() << RHS->getSourceRange(); 4220 return QualType(); 4221} 4222 4223/// FindCompositeObjCPointerType - Helper method to find composite type of 4224/// two objective-c pointer types of the two input expressions. 4225QualType Sema::FindCompositeObjCPointerType(Expr *&LHS, Expr *&RHS, 4226 SourceLocation QuestionLoc) { 4227 QualType LHSTy = LHS->getType(); 4228 QualType RHSTy = RHS->getType(); 4229 4230 // Handle things like Class and struct objc_class*. Here we case the result 4231 // to the pseudo-builtin, because that will be implicitly cast back to the 4232 // redefinition type if an attempt is made to access its fields. 4233 if (LHSTy->isObjCClassType() && 4234 (RHSTy.getDesugaredType() == Context.ObjCClassRedefinitionType)) { 4235 ImpCastExprToType(RHS, LHSTy, CastExpr::CK_BitCast); 4236 return LHSTy; 4237 } 4238 if (RHSTy->isObjCClassType() && 4239 (LHSTy.getDesugaredType() == Context.ObjCClassRedefinitionType)) { 4240 ImpCastExprToType(LHS, RHSTy, CastExpr::CK_BitCast); 4241 return RHSTy; 4242 } 4243 // And the same for struct objc_object* / id 4244 if (LHSTy->isObjCIdType() && 4245 (RHSTy.getDesugaredType() == Context.ObjCIdRedefinitionType)) { 4246 ImpCastExprToType(RHS, LHSTy, CastExpr::CK_BitCast); 4247 return LHSTy; 4248 } 4249 if (RHSTy->isObjCIdType() && 4250 (LHSTy.getDesugaredType() == Context.ObjCIdRedefinitionType)) { 4251 ImpCastExprToType(LHS, RHSTy, CastExpr::CK_BitCast); 4252 return RHSTy; 4253 } 4254 // And the same for struct objc_selector* / SEL 4255 if (Context.isObjCSelType(LHSTy) && 4256 (RHSTy.getDesugaredType() == Context.ObjCSelRedefinitionType)) { 4257 ImpCastExprToType(RHS, LHSTy, CastExpr::CK_BitCast); 4258 return LHSTy; 4259 } 4260 if (Context.isObjCSelType(RHSTy) && 4261 (LHSTy.getDesugaredType() == Context.ObjCSelRedefinitionType)) { 4262 ImpCastExprToType(LHS, RHSTy, CastExpr::CK_BitCast); 4263 return RHSTy; 4264 } 4265 // Check constraints for Objective-C object pointers types. 4266 if (LHSTy->isObjCObjectPointerType() && RHSTy->isObjCObjectPointerType()) { 4267 4268 if (Context.getCanonicalType(LHSTy) == Context.getCanonicalType(RHSTy)) { 4269 // Two identical object pointer types are always compatible. 4270 return LHSTy; 4271 } 4272 const ObjCObjectPointerType *LHSOPT = LHSTy->getAs<ObjCObjectPointerType>(); 4273 const ObjCObjectPointerType *RHSOPT = RHSTy->getAs<ObjCObjectPointerType>(); 4274 QualType compositeType = LHSTy; 4275 4276 // If both operands are interfaces and either operand can be 4277 // assigned to the other, use that type as the composite 4278 // type. This allows 4279 // xxx ? (A*) a : (B*) b 4280 // where B is a subclass of A. 4281 // 4282 // Additionally, as for assignment, if either type is 'id' 4283 // allow silent coercion. Finally, if the types are 4284 // incompatible then make sure to use 'id' as the composite 4285 // type so the result is acceptable for sending messages to. 4286 4287 // FIXME: Consider unifying with 'areComparableObjCPointerTypes'. 4288 // It could return the composite type. 4289 if (Context.canAssignObjCInterfaces(LHSOPT, RHSOPT)) { 4290 compositeType = RHSOPT->isObjCBuiltinType() ? RHSTy : LHSTy; 4291 } else if (Context.canAssignObjCInterfaces(RHSOPT, LHSOPT)) { 4292 compositeType = LHSOPT->isObjCBuiltinType() ? LHSTy : RHSTy; 4293 } else if ((LHSTy->isObjCQualifiedIdType() || 4294 RHSTy->isObjCQualifiedIdType()) && 4295 Context.ObjCQualifiedIdTypesAreCompatible(LHSTy, RHSTy, true)) { 4296 // Need to handle "id<xx>" explicitly. 4297 // GCC allows qualified id and any Objective-C type to devolve to 4298 // id. Currently localizing to here until clear this should be 4299 // part of ObjCQualifiedIdTypesAreCompatible. 4300 compositeType = Context.getObjCIdType(); 4301 } else if (LHSTy->isObjCIdType() || RHSTy->isObjCIdType()) { 4302 compositeType = Context.getObjCIdType(); 4303 } else if (!(compositeType = 4304 Context.areCommonBaseCompatible(LHSOPT, RHSOPT)).isNull()) 4305 ; 4306 else { 4307 Diag(QuestionLoc, diag::ext_typecheck_cond_incompatible_operands) 4308 << LHSTy << RHSTy 4309 << LHS->getSourceRange() << RHS->getSourceRange(); 4310 QualType incompatTy = Context.getObjCIdType(); 4311 ImpCastExprToType(LHS, incompatTy, CastExpr::CK_BitCast); 4312 ImpCastExprToType(RHS, incompatTy, CastExpr::CK_BitCast); 4313 return incompatTy; 4314 } 4315 // The object pointer types are compatible. 4316 ImpCastExprToType(LHS, compositeType, CastExpr::CK_BitCast); 4317 ImpCastExprToType(RHS, compositeType, CastExpr::CK_BitCast); 4318 return compositeType; 4319 } 4320 // Check Objective-C object pointer types and 'void *' 4321 if (LHSTy->isVoidPointerType() && RHSTy->isObjCObjectPointerType()) { 4322 QualType lhptee = LHSTy->getAs<PointerType>()->getPointeeType(); 4323 QualType rhptee = RHSTy->getAs<ObjCObjectPointerType>()->getPointeeType(); 4324 QualType destPointee 4325 = Context.getQualifiedType(lhptee, rhptee.getQualifiers()); 4326 QualType destType = Context.getPointerType(destPointee); 4327 // Add qualifiers if necessary. 4328 ImpCastExprToType(LHS, destType, CastExpr::CK_NoOp); 4329 // Promote to void*. 4330 ImpCastExprToType(RHS, destType, CastExpr::CK_BitCast); 4331 return destType; 4332 } 4333 if (LHSTy->isObjCObjectPointerType() && RHSTy->isVoidPointerType()) { 4334 QualType lhptee = LHSTy->getAs<ObjCObjectPointerType>()->getPointeeType(); 4335 QualType rhptee = RHSTy->getAs<PointerType>()->getPointeeType(); 4336 QualType destPointee 4337 = Context.getQualifiedType(rhptee, lhptee.getQualifiers()); 4338 QualType destType = Context.getPointerType(destPointee); 4339 // Add qualifiers if necessary. 4340 ImpCastExprToType(RHS, destType, CastExpr::CK_NoOp); 4341 // Promote to void*. 4342 ImpCastExprToType(LHS, destType, CastExpr::CK_BitCast); 4343 return destType; 4344 } 4345 return QualType(); 4346} 4347 4348/// ActOnConditionalOp - Parse a ?: operation. Note that 'LHS' may be null 4349/// in the case of a the GNU conditional expr extension. 4350Action::OwningExprResult Sema::ActOnConditionalOp(SourceLocation QuestionLoc, 4351 SourceLocation ColonLoc, 4352 ExprArg Cond, ExprArg LHS, 4353 ExprArg RHS) { 4354 Expr *CondExpr = (Expr *) Cond.get(); 4355 Expr *LHSExpr = (Expr *) LHS.get(), *RHSExpr = (Expr *) RHS.get(); 4356 4357 // If this is the gnu "x ?: y" extension, analyze the types as though the LHS 4358 // was the condition. 4359 bool isLHSNull = LHSExpr == 0; 4360 if (isLHSNull) 4361 LHSExpr = CondExpr; 4362 4363 QualType result = CheckConditionalOperands(CondExpr, LHSExpr, 4364 RHSExpr, QuestionLoc); 4365 if (result.isNull()) 4366 return ExprError(); 4367 4368 Cond.release(); 4369 LHS.release(); 4370 RHS.release(); 4371 return Owned(new (Context) ConditionalOperator(CondExpr, QuestionLoc, 4372 isLHSNull ? 0 : LHSExpr, 4373 ColonLoc, RHSExpr, result)); 4374} 4375 4376// CheckPointerTypesForAssignment - This is a very tricky routine (despite 4377// being closely modeled after the C99 spec:-). The odd characteristic of this 4378// routine is it effectively iqnores the qualifiers on the top level pointee. 4379// This circumvents the usual type rules specified in 6.2.7p1 & 6.7.5.[1-3]. 4380// FIXME: add a couple examples in this comment. 4381Sema::AssignConvertType 4382Sema::CheckPointerTypesForAssignment(QualType lhsType, QualType rhsType) { 4383 QualType lhptee, rhptee; 4384 4385 if ((lhsType->isObjCClassType() && 4386 (rhsType.getDesugaredType() == Context.ObjCClassRedefinitionType)) || 4387 (rhsType->isObjCClassType() && 4388 (lhsType.getDesugaredType() == Context.ObjCClassRedefinitionType))) { 4389 return Compatible; 4390 } 4391 4392 // get the "pointed to" type (ignoring qualifiers at the top level) 4393 lhptee = lhsType->getAs<PointerType>()->getPointeeType(); 4394 rhptee = rhsType->getAs<PointerType>()->getPointeeType(); 4395 4396 // make sure we operate on the canonical type 4397 lhptee = Context.getCanonicalType(lhptee); 4398 rhptee = Context.getCanonicalType(rhptee); 4399 4400 AssignConvertType ConvTy = Compatible; 4401 4402 // C99 6.5.16.1p1: This following citation is common to constraints 4403 // 3 & 4 (below). ...and the type *pointed to* by the left has all the 4404 // qualifiers of the type *pointed to* by the right; 4405 // FIXME: Handle ExtQualType 4406 if (!lhptee.isAtLeastAsQualifiedAs(rhptee)) 4407 ConvTy = CompatiblePointerDiscardsQualifiers; 4408 4409 // C99 6.5.16.1p1 (constraint 4): If one operand is a pointer to an object or 4410 // incomplete type and the other is a pointer to a qualified or unqualified 4411 // version of void... 4412 if (lhptee->isVoidType()) { 4413 if (rhptee->isIncompleteOrObjectType()) 4414 return ConvTy; 4415 4416 // As an extension, we allow cast to/from void* to function pointer. 4417 assert(rhptee->isFunctionType()); 4418 return FunctionVoidPointer; 4419 } 4420 4421 if (rhptee->isVoidType()) { 4422 if (lhptee->isIncompleteOrObjectType()) 4423 return ConvTy; 4424 4425 // As an extension, we allow cast to/from void* to function pointer. 4426 assert(lhptee->isFunctionType()); 4427 return FunctionVoidPointer; 4428 } 4429 // C99 6.5.16.1p1 (constraint 3): both operands are pointers to qualified or 4430 // unqualified versions of compatible types, ... 4431 lhptee = lhptee.getUnqualifiedType(); 4432 rhptee = rhptee.getUnqualifiedType(); 4433 if (!Context.typesAreCompatible(lhptee, rhptee)) { 4434 // Check if the pointee types are compatible ignoring the sign. 4435 // We explicitly check for char so that we catch "char" vs 4436 // "unsigned char" on systems where "char" is unsigned. 4437 if (lhptee->isCharType()) 4438 lhptee = Context.UnsignedCharTy; 4439 else if (lhptee->isSignedIntegerType()) 4440 lhptee = Context.getCorrespondingUnsignedType(lhptee); 4441 4442 if (rhptee->isCharType()) 4443 rhptee = Context.UnsignedCharTy; 4444 else if (rhptee->isSignedIntegerType()) 4445 rhptee = Context.getCorrespondingUnsignedType(rhptee); 4446 4447 if (lhptee == rhptee) { 4448 // Types are compatible ignoring the sign. Qualifier incompatibility 4449 // takes priority over sign incompatibility because the sign 4450 // warning can be disabled. 4451 if (ConvTy != Compatible) 4452 return ConvTy; 4453 return IncompatiblePointerSign; 4454 } 4455 4456 // If we are a multi-level pointer, it's possible that our issue is simply 4457 // one of qualification - e.g. char ** -> const char ** is not allowed. If 4458 // the eventual target type is the same and the pointers have the same 4459 // level of indirection, this must be the issue. 4460 if (lhptee->isPointerType() && rhptee->isPointerType()) { 4461 do { 4462 lhptee = lhptee->getAs<PointerType>()->getPointeeType(); 4463 rhptee = rhptee->getAs<PointerType>()->getPointeeType(); 4464 4465 lhptee = Context.getCanonicalType(lhptee); 4466 rhptee = Context.getCanonicalType(rhptee); 4467 } while (lhptee->isPointerType() && rhptee->isPointerType()); 4468 4469 if (Context.hasSameUnqualifiedType(lhptee, rhptee)) 4470 return IncompatibleNestedPointerQualifiers; 4471 } 4472 4473 // General pointer incompatibility takes priority over qualifiers. 4474 return IncompatiblePointer; 4475 } 4476 return ConvTy; 4477} 4478 4479/// CheckBlockPointerTypesForAssignment - This routine determines whether two 4480/// block pointer types are compatible or whether a block and normal pointer 4481/// are compatible. It is more restrict than comparing two function pointer 4482// types. 4483Sema::AssignConvertType 4484Sema::CheckBlockPointerTypesForAssignment(QualType lhsType, 4485 QualType rhsType) { 4486 QualType lhptee, rhptee; 4487 4488 // get the "pointed to" type (ignoring qualifiers at the top level) 4489 lhptee = lhsType->getAs<BlockPointerType>()->getPointeeType(); 4490 rhptee = rhsType->getAs<BlockPointerType>()->getPointeeType(); 4491 4492 // make sure we operate on the canonical type 4493 lhptee = Context.getCanonicalType(lhptee); 4494 rhptee = Context.getCanonicalType(rhptee); 4495 4496 AssignConvertType ConvTy = Compatible; 4497 4498 // For blocks we enforce that qualifiers are identical. 4499 if (lhptee.getLocalCVRQualifiers() != rhptee.getLocalCVRQualifiers()) 4500 ConvTy = CompatiblePointerDiscardsQualifiers; 4501 4502 if (!Context.typesAreCompatible(lhptee, rhptee)) 4503 return IncompatibleBlockPointer; 4504 return ConvTy; 4505} 4506 4507/// CheckObjCPointerTypesForAssignment - Compares two objective-c pointer types 4508/// for assignment compatibility. 4509Sema::AssignConvertType 4510Sema::CheckObjCPointerTypesForAssignment(QualType lhsType, QualType rhsType) { 4511 if (lhsType->isObjCBuiltinType() || rhsType->isObjCBuiltinType()) 4512 return Compatible; 4513 QualType lhptee = 4514 lhsType->getAs<ObjCObjectPointerType>()->getPointeeType(); 4515 QualType rhptee = 4516 rhsType->getAs<ObjCObjectPointerType>()->getPointeeType(); 4517 // make sure we operate on the canonical type 4518 lhptee = Context.getCanonicalType(lhptee); 4519 rhptee = Context.getCanonicalType(rhptee); 4520 if (!lhptee.isAtLeastAsQualifiedAs(rhptee)) 4521 return CompatiblePointerDiscardsQualifiers; 4522 4523 if (Context.typesAreCompatible(lhsType, rhsType)) 4524 return Compatible; 4525 if (lhsType->isObjCQualifiedIdType() || rhsType->isObjCQualifiedIdType()) 4526 return IncompatibleObjCQualifiedId; 4527 return IncompatiblePointer; 4528} 4529 4530/// CheckAssignmentConstraints (C99 6.5.16) - This routine currently 4531/// has code to accommodate several GCC extensions when type checking 4532/// pointers. Here are some objectionable examples that GCC considers warnings: 4533/// 4534/// int a, *pint; 4535/// short *pshort; 4536/// struct foo *pfoo; 4537/// 4538/// pint = pshort; // warning: assignment from incompatible pointer type 4539/// a = pint; // warning: assignment makes integer from pointer without a cast 4540/// pint = a; // warning: assignment makes pointer from integer without a cast 4541/// pint = pfoo; // warning: assignment from incompatible pointer type 4542/// 4543/// As a result, the code for dealing with pointers is more complex than the 4544/// C99 spec dictates. 4545/// 4546Sema::AssignConvertType 4547Sema::CheckAssignmentConstraints(QualType lhsType, QualType rhsType) { 4548 // Get canonical types. We're not formatting these types, just comparing 4549 // them. 4550 lhsType = Context.getCanonicalType(lhsType).getUnqualifiedType(); 4551 rhsType = Context.getCanonicalType(rhsType).getUnqualifiedType(); 4552 4553 if (lhsType == rhsType) 4554 return Compatible; // Common case: fast path an exact match. 4555 4556 if ((lhsType->isObjCClassType() && 4557 (rhsType.getDesugaredType() == Context.ObjCClassRedefinitionType)) || 4558 (rhsType->isObjCClassType() && 4559 (lhsType.getDesugaredType() == Context.ObjCClassRedefinitionType))) { 4560 return Compatible; 4561 } 4562 4563 // If the left-hand side is a reference type, then we are in a 4564 // (rare!) case where we've allowed the use of references in C, 4565 // e.g., as a parameter type in a built-in function. In this case, 4566 // just make sure that the type referenced is compatible with the 4567 // right-hand side type. The caller is responsible for adjusting 4568 // lhsType so that the resulting expression does not have reference 4569 // type. 4570 if (const ReferenceType *lhsTypeRef = lhsType->getAs<ReferenceType>()) { 4571 if (Context.typesAreCompatible(lhsTypeRef->getPointeeType(), rhsType)) 4572 return Compatible; 4573 return Incompatible; 4574 } 4575 // Allow scalar to ExtVector assignments, and assignments of an ExtVector type 4576 // to the same ExtVector type. 4577 if (lhsType->isExtVectorType()) { 4578 if (rhsType->isExtVectorType()) 4579 return lhsType == rhsType ? Compatible : Incompatible; 4580 if (!rhsType->isVectorType() && rhsType->isArithmeticType()) 4581 return Compatible; 4582 } 4583 4584 if (lhsType->isVectorType() || rhsType->isVectorType()) { 4585 // If we are allowing lax vector conversions, and LHS and RHS are both 4586 // vectors, the total size only needs to be the same. This is a bitcast; 4587 // no bits are changed but the result type is different. 4588 if (getLangOptions().LaxVectorConversions && 4589 lhsType->isVectorType() && rhsType->isVectorType()) { 4590 if (Context.getTypeSize(lhsType) == Context.getTypeSize(rhsType)) 4591 return IncompatibleVectors; 4592 } 4593 return Incompatible; 4594 } 4595 4596 if (lhsType->isArithmeticType() && rhsType->isArithmeticType()) 4597 return Compatible; 4598 4599 if (isa<PointerType>(lhsType)) { 4600 if (rhsType->isIntegerType()) 4601 return IntToPointer; 4602 4603 if (isa<PointerType>(rhsType)) 4604 return CheckPointerTypesForAssignment(lhsType, rhsType); 4605 4606 // In general, C pointers are not compatible with ObjC object pointers. 4607 if (isa<ObjCObjectPointerType>(rhsType)) { 4608 if (lhsType->isVoidPointerType()) // an exception to the rule. 4609 return Compatible; 4610 return IncompatiblePointer; 4611 } 4612 if (rhsType->getAs<BlockPointerType>()) { 4613 if (lhsType->getAs<PointerType>()->getPointeeType()->isVoidType()) 4614 return Compatible; 4615 4616 // Treat block pointers as objects. 4617 if (getLangOptions().ObjC1 && lhsType->isObjCIdType()) 4618 return Compatible; 4619 } 4620 return Incompatible; 4621 } 4622 4623 if (isa<BlockPointerType>(lhsType)) { 4624 if (rhsType->isIntegerType()) 4625 return IntToBlockPointer; 4626 4627 // Treat block pointers as objects. 4628 if (getLangOptions().ObjC1 && rhsType->isObjCIdType()) 4629 return Compatible; 4630 4631 if (rhsType->isBlockPointerType()) 4632 return CheckBlockPointerTypesForAssignment(lhsType, rhsType); 4633 4634 if (const PointerType *RHSPT = rhsType->getAs<PointerType>()) { 4635 if (RHSPT->getPointeeType()->isVoidType()) 4636 return Compatible; 4637 } 4638 return Incompatible; 4639 } 4640 4641 if (isa<ObjCObjectPointerType>(lhsType)) { 4642 if (rhsType->isIntegerType()) 4643 return IntToPointer; 4644 4645 // In general, C pointers are not compatible with ObjC object pointers. 4646 if (isa<PointerType>(rhsType)) { 4647 if (rhsType->isVoidPointerType()) // an exception to the rule. 4648 return Compatible; 4649 return IncompatiblePointer; 4650 } 4651 if (rhsType->isObjCObjectPointerType()) { 4652 return CheckObjCPointerTypesForAssignment(lhsType, rhsType); 4653 } 4654 if (const PointerType *RHSPT = rhsType->getAs<PointerType>()) { 4655 if (RHSPT->getPointeeType()->isVoidType()) 4656 return Compatible; 4657 } 4658 // Treat block pointers as objects. 4659 if (rhsType->isBlockPointerType()) 4660 return Compatible; 4661 return Incompatible; 4662 } 4663 if (isa<PointerType>(rhsType)) { 4664 // C99 6.5.16.1p1: the left operand is _Bool and the right is a pointer. 4665 if (lhsType == Context.BoolTy) 4666 return Compatible; 4667 4668 if (lhsType->isIntegerType()) 4669 return PointerToInt; 4670 4671 if (isa<PointerType>(lhsType)) 4672 return CheckPointerTypesForAssignment(lhsType, rhsType); 4673 4674 if (isa<BlockPointerType>(lhsType) && 4675 rhsType->getAs<PointerType>()->getPointeeType()->isVoidType()) 4676 return Compatible; 4677 return Incompatible; 4678 } 4679 if (isa<ObjCObjectPointerType>(rhsType)) { 4680 // C99 6.5.16.1p1: the left operand is _Bool and the right is a pointer. 4681 if (lhsType == Context.BoolTy) 4682 return Compatible; 4683 4684 if (lhsType->isIntegerType()) 4685 return PointerToInt; 4686 4687 // In general, C pointers are not compatible with ObjC object pointers. 4688 if (isa<PointerType>(lhsType)) { 4689 if (lhsType->isVoidPointerType()) // an exception to the rule. 4690 return Compatible; 4691 return IncompatiblePointer; 4692 } 4693 if (isa<BlockPointerType>(lhsType) && 4694 rhsType->getAs<PointerType>()->getPointeeType()->isVoidType()) 4695 return Compatible; 4696 return Incompatible; 4697 } 4698 4699 if (isa<TagType>(lhsType) && isa<TagType>(rhsType)) { 4700 if (Context.typesAreCompatible(lhsType, rhsType)) 4701 return Compatible; 4702 } 4703 return Incompatible; 4704} 4705 4706/// \brief Constructs a transparent union from an expression that is 4707/// used to initialize the transparent union. 4708static void ConstructTransparentUnion(ASTContext &C, Expr *&E, 4709 QualType UnionType, FieldDecl *Field) { 4710 // Build an initializer list that designates the appropriate member 4711 // of the transparent union. 4712 InitListExpr *Initializer = new (C) InitListExpr(SourceLocation(), 4713 &E, 1, 4714 SourceLocation()); 4715 Initializer->setType(UnionType); 4716 Initializer->setInitializedFieldInUnion(Field); 4717 4718 // Build a compound literal constructing a value of the transparent 4719 // union type from this initializer list. 4720 TypeSourceInfo *unionTInfo = C.getTrivialTypeSourceInfo(UnionType); 4721 E = new (C) CompoundLiteralExpr(SourceLocation(), unionTInfo, UnionType, 4722 Initializer, false); 4723} 4724 4725Sema::AssignConvertType 4726Sema::CheckTransparentUnionArgumentConstraints(QualType ArgType, Expr *&rExpr) { 4727 QualType FromType = rExpr->getType(); 4728 4729 // If the ArgType is a Union type, we want to handle a potential 4730 // transparent_union GCC extension. 4731 const RecordType *UT = ArgType->getAsUnionType(); 4732 if (!UT || !UT->getDecl()->hasAttr<TransparentUnionAttr>()) 4733 return Incompatible; 4734 4735 // The field to initialize within the transparent union. 4736 RecordDecl *UD = UT->getDecl(); 4737 FieldDecl *InitField = 0; 4738 // It's compatible if the expression matches any of the fields. 4739 for (RecordDecl::field_iterator it = UD->field_begin(), 4740 itend = UD->field_end(); 4741 it != itend; ++it) { 4742 if (it->getType()->isPointerType()) { 4743 // If the transparent union contains a pointer type, we allow: 4744 // 1) void pointer 4745 // 2) null pointer constant 4746 if (FromType->isPointerType()) 4747 if (FromType->getAs<PointerType>()->getPointeeType()->isVoidType()) { 4748 ImpCastExprToType(rExpr, it->getType(), CastExpr::CK_BitCast); 4749 InitField = *it; 4750 break; 4751 } 4752 4753 if (rExpr->isNullPointerConstant(Context, 4754 Expr::NPC_ValueDependentIsNull)) { 4755 ImpCastExprToType(rExpr, it->getType(), CastExpr::CK_IntegralToPointer); 4756 InitField = *it; 4757 break; 4758 } 4759 } 4760 4761 if (CheckAssignmentConstraints(it->getType(), rExpr->getType()) 4762 == Compatible) { 4763 InitField = *it; 4764 break; 4765 } 4766 } 4767 4768 if (!InitField) 4769 return Incompatible; 4770 4771 ConstructTransparentUnion(Context, rExpr, ArgType, InitField); 4772 return Compatible; 4773} 4774 4775Sema::AssignConvertType 4776Sema::CheckSingleAssignmentConstraints(QualType lhsType, Expr *&rExpr) { 4777 if (getLangOptions().CPlusPlus) { 4778 if (!lhsType->isRecordType()) { 4779 // C++ 5.17p3: If the left operand is not of class type, the 4780 // expression is implicitly converted (C++ 4) to the 4781 // cv-unqualified type of the left operand. 4782 if (PerformImplicitConversion(rExpr, lhsType.getUnqualifiedType(), 4783 AA_Assigning)) 4784 return Incompatible; 4785 return Compatible; 4786 } 4787 4788 // FIXME: Currently, we fall through and treat C++ classes like C 4789 // structures. 4790 } 4791 4792 // C99 6.5.16.1p1: the left operand is a pointer and the right is 4793 // a null pointer constant. 4794 if ((lhsType->isPointerType() || 4795 lhsType->isObjCObjectPointerType() || 4796 lhsType->isBlockPointerType()) 4797 && rExpr->isNullPointerConstant(Context, 4798 Expr::NPC_ValueDependentIsNull)) { 4799 ImpCastExprToType(rExpr, lhsType, CastExpr::CK_Unknown); 4800 return Compatible; 4801 } 4802 4803 // This check seems unnatural, however it is necessary to ensure the proper 4804 // conversion of functions/arrays. If the conversion were done for all 4805 // DeclExpr's (created by ActOnIdExpression), it would mess up the unary 4806 // expressions that surpress this implicit conversion (&, sizeof). 4807 // 4808 // Suppress this for references: C++ 8.5.3p5. 4809 if (!lhsType->isReferenceType()) 4810 DefaultFunctionArrayConversion(rExpr); 4811 4812 Sema::AssignConvertType result = 4813 CheckAssignmentConstraints(lhsType, rExpr->getType()); 4814 4815 // C99 6.5.16.1p2: The value of the right operand is converted to the 4816 // type of the assignment expression. 4817 // CheckAssignmentConstraints allows the left-hand side to be a reference, 4818 // so that we can use references in built-in functions even in C. 4819 // The getNonReferenceType() call makes sure that the resulting expression 4820 // does not have reference type. 4821 if (result != Incompatible && rExpr->getType() != lhsType) 4822 ImpCastExprToType(rExpr, lhsType.getNonReferenceType(), 4823 CastExpr::CK_Unknown); 4824 return result; 4825} 4826 4827QualType Sema::InvalidOperands(SourceLocation Loc, Expr *&lex, Expr *&rex) { 4828 Diag(Loc, diag::err_typecheck_invalid_operands) 4829 << lex->getType() << rex->getType() 4830 << lex->getSourceRange() << rex->getSourceRange(); 4831 return QualType(); 4832} 4833 4834QualType Sema::CheckVectorOperands(SourceLocation Loc, Expr *&lex, Expr *&rex) { 4835 // For conversion purposes, we ignore any qualifiers. 4836 // For example, "const float" and "float" are equivalent. 4837 QualType lhsType = 4838 Context.getCanonicalType(lex->getType()).getUnqualifiedType(); 4839 QualType rhsType = 4840 Context.getCanonicalType(rex->getType()).getUnqualifiedType(); 4841 4842 // If the vector types are identical, return. 4843 if (lhsType == rhsType) 4844 return lhsType; 4845 4846 // Handle the case of a vector & extvector type of the same size and element 4847 // type. It would be nice if we only had one vector type someday. 4848 if (getLangOptions().LaxVectorConversions) { 4849 // FIXME: Should we warn here? 4850 if (const VectorType *LV = lhsType->getAs<VectorType>()) { 4851 if (const VectorType *RV = rhsType->getAs<VectorType>()) 4852 if (LV->getElementType() == RV->getElementType() && 4853 LV->getNumElements() == RV->getNumElements()) { 4854 return lhsType->isExtVectorType() ? lhsType : rhsType; 4855 } 4856 } 4857 } 4858 4859 // Canonicalize the ExtVector to the LHS, remember if we swapped so we can 4860 // swap back (so that we don't reverse the inputs to a subtract, for instance. 4861 bool swapped = false; 4862 if (rhsType->isExtVectorType()) { 4863 swapped = true; 4864 std::swap(rex, lex); 4865 std::swap(rhsType, lhsType); 4866 } 4867 4868 // Handle the case of an ext vector and scalar. 4869 if (const ExtVectorType *LV = lhsType->getAs<ExtVectorType>()) { 4870 QualType EltTy = LV->getElementType(); 4871 if (EltTy->isIntegralType() && rhsType->isIntegralType()) { 4872 if (Context.getIntegerTypeOrder(EltTy, rhsType) >= 0) { 4873 ImpCastExprToType(rex, lhsType, CastExpr::CK_IntegralCast); 4874 if (swapped) std::swap(rex, lex); 4875 return lhsType; 4876 } 4877 } 4878 if (EltTy->isRealFloatingType() && rhsType->isScalarType() && 4879 rhsType->isRealFloatingType()) { 4880 if (Context.getFloatingTypeOrder(EltTy, rhsType) >= 0) { 4881 ImpCastExprToType(rex, lhsType, CastExpr::CK_FloatingCast); 4882 if (swapped) std::swap(rex, lex); 4883 return lhsType; 4884 } 4885 } 4886 } 4887 4888 // Vectors of different size or scalar and non-ext-vector are errors. 4889 Diag(Loc, diag::err_typecheck_vector_not_convertable) 4890 << lex->getType() << rex->getType() 4891 << lex->getSourceRange() << rex->getSourceRange(); 4892 return QualType(); 4893} 4894 4895QualType Sema::CheckMultiplyDivideOperands( 4896 Expr *&lex, Expr *&rex, SourceLocation Loc, bool isCompAssign, bool isDiv) { 4897 if (lex->getType()->isVectorType() || rex->getType()->isVectorType()) 4898 return CheckVectorOperands(Loc, lex, rex); 4899 4900 QualType compType = UsualArithmeticConversions(lex, rex, isCompAssign); 4901 4902 if (!lex->getType()->isArithmeticType() || 4903 !rex->getType()->isArithmeticType()) 4904 return InvalidOperands(Loc, lex, rex); 4905 4906 // Check for division by zero. 4907 if (isDiv && 4908 rex->isNullPointerConstant(Context, Expr::NPC_ValueDependentIsNotNull)) 4909 DiagRuntimeBehavior(Loc, PDiag(diag::warn_division_by_zero) 4910 << rex->getSourceRange()); 4911 4912 return compType; 4913} 4914 4915QualType Sema::CheckRemainderOperands( 4916 Expr *&lex, Expr *&rex, SourceLocation Loc, bool isCompAssign) { 4917 if (lex->getType()->isVectorType() || rex->getType()->isVectorType()) { 4918 if (lex->getType()->isIntegerType() && rex->getType()->isIntegerType()) 4919 return CheckVectorOperands(Loc, lex, rex); 4920 return InvalidOperands(Loc, lex, rex); 4921 } 4922 4923 QualType compType = UsualArithmeticConversions(lex, rex, isCompAssign); 4924 4925 if (!lex->getType()->isIntegerType() || !rex->getType()->isIntegerType()) 4926 return InvalidOperands(Loc, lex, rex); 4927 4928 // Check for remainder by zero. 4929 if (rex->isNullPointerConstant(Context, Expr::NPC_ValueDependentIsNotNull)) 4930 DiagRuntimeBehavior(Loc, PDiag(diag::warn_remainder_by_zero) 4931 << rex->getSourceRange()); 4932 4933 return compType; 4934} 4935 4936QualType Sema::CheckAdditionOperands( // C99 6.5.6 4937 Expr *&lex, Expr *&rex, SourceLocation Loc, QualType* CompLHSTy) { 4938 if (lex->getType()->isVectorType() || rex->getType()->isVectorType()) { 4939 QualType compType = CheckVectorOperands(Loc, lex, rex); 4940 if (CompLHSTy) *CompLHSTy = compType; 4941 return compType; 4942 } 4943 4944 QualType compType = UsualArithmeticConversions(lex, rex, CompLHSTy); 4945 4946 // handle the common case first (both operands are arithmetic). 4947 if (lex->getType()->isArithmeticType() && 4948 rex->getType()->isArithmeticType()) { 4949 if (CompLHSTy) *CompLHSTy = compType; 4950 return compType; 4951 } 4952 4953 // Put any potential pointer into PExp 4954 Expr* PExp = lex, *IExp = rex; 4955 if (IExp->getType()->isAnyPointerType()) 4956 std::swap(PExp, IExp); 4957 4958 if (PExp->getType()->isAnyPointerType()) { 4959 4960 if (IExp->getType()->isIntegerType()) { 4961 QualType PointeeTy = PExp->getType()->getPointeeType(); 4962 4963 // Check for arithmetic on pointers to incomplete types. 4964 if (PointeeTy->isVoidType()) { 4965 if (getLangOptions().CPlusPlus) { 4966 Diag(Loc, diag::err_typecheck_pointer_arith_void_type) 4967 << lex->getSourceRange() << rex->getSourceRange(); 4968 return QualType(); 4969 } 4970 4971 // GNU extension: arithmetic on pointer to void 4972 Diag(Loc, diag::ext_gnu_void_ptr) 4973 << lex->getSourceRange() << rex->getSourceRange(); 4974 } else if (PointeeTy->isFunctionType()) { 4975 if (getLangOptions().CPlusPlus) { 4976 Diag(Loc, diag::err_typecheck_pointer_arith_function_type) 4977 << lex->getType() << lex->getSourceRange(); 4978 return QualType(); 4979 } 4980 4981 // GNU extension: arithmetic on pointer to function 4982 Diag(Loc, diag::ext_gnu_ptr_func_arith) 4983 << lex->getType() << lex->getSourceRange(); 4984 } else { 4985 // Check if we require a complete type. 4986 if (((PExp->getType()->isPointerType() && 4987 !PExp->getType()->isDependentType()) || 4988 PExp->getType()->isObjCObjectPointerType()) && 4989 RequireCompleteType(Loc, PointeeTy, 4990 PDiag(diag::err_typecheck_arithmetic_incomplete_type) 4991 << PExp->getSourceRange() 4992 << PExp->getType())) 4993 return QualType(); 4994 } 4995 // Diagnose bad cases where we step over interface counts. 4996 if (PointeeTy->isObjCInterfaceType() && LangOpts.ObjCNonFragileABI) { 4997 Diag(Loc, diag::err_arithmetic_nonfragile_interface) 4998 << PointeeTy << PExp->getSourceRange(); 4999 return QualType(); 5000 } 5001 5002 if (CompLHSTy) { 5003 QualType LHSTy = Context.isPromotableBitField(lex); 5004 if (LHSTy.isNull()) { 5005 LHSTy = lex->getType(); 5006 if (LHSTy->isPromotableIntegerType()) 5007 LHSTy = Context.getPromotedIntegerType(LHSTy); 5008 } 5009 *CompLHSTy = LHSTy; 5010 } 5011 return PExp->getType(); 5012 } 5013 } 5014 5015 return InvalidOperands(Loc, lex, rex); 5016} 5017 5018// C99 6.5.6 5019QualType Sema::CheckSubtractionOperands(Expr *&lex, Expr *&rex, 5020 SourceLocation Loc, QualType* CompLHSTy) { 5021 if (lex->getType()->isVectorType() || rex->getType()->isVectorType()) { 5022 QualType compType = CheckVectorOperands(Loc, lex, rex); 5023 if (CompLHSTy) *CompLHSTy = compType; 5024 return compType; 5025 } 5026 5027 QualType compType = UsualArithmeticConversions(lex, rex, CompLHSTy); 5028 5029 // Enforce type constraints: C99 6.5.6p3. 5030 5031 // Handle the common case first (both operands are arithmetic). 5032 if (lex->getType()->isArithmeticType() 5033 && rex->getType()->isArithmeticType()) { 5034 if (CompLHSTy) *CompLHSTy = compType; 5035 return compType; 5036 } 5037 5038 // Either ptr - int or ptr - ptr. 5039 if (lex->getType()->isAnyPointerType()) { 5040 QualType lpointee = lex->getType()->getPointeeType(); 5041 5042 // The LHS must be an completely-defined object type. 5043 5044 bool ComplainAboutVoid = false; 5045 Expr *ComplainAboutFunc = 0; 5046 if (lpointee->isVoidType()) { 5047 if (getLangOptions().CPlusPlus) { 5048 Diag(Loc, diag::err_typecheck_pointer_arith_void_type) 5049 << lex->getSourceRange() << rex->getSourceRange(); 5050 return QualType(); 5051 } 5052 5053 // GNU C extension: arithmetic on pointer to void 5054 ComplainAboutVoid = true; 5055 } else if (lpointee->isFunctionType()) { 5056 if (getLangOptions().CPlusPlus) { 5057 Diag(Loc, diag::err_typecheck_pointer_arith_function_type) 5058 << lex->getType() << lex->getSourceRange(); 5059 return QualType(); 5060 } 5061 5062 // GNU C extension: arithmetic on pointer to function 5063 ComplainAboutFunc = lex; 5064 } else if (!lpointee->isDependentType() && 5065 RequireCompleteType(Loc, lpointee, 5066 PDiag(diag::err_typecheck_sub_ptr_object) 5067 << lex->getSourceRange() 5068 << lex->getType())) 5069 return QualType(); 5070 5071 // Diagnose bad cases where we step over interface counts. 5072 if (lpointee->isObjCInterfaceType() && LangOpts.ObjCNonFragileABI) { 5073 Diag(Loc, diag::err_arithmetic_nonfragile_interface) 5074 << lpointee << lex->getSourceRange(); 5075 return QualType(); 5076 } 5077 5078 // The result type of a pointer-int computation is the pointer type. 5079 if (rex->getType()->isIntegerType()) { 5080 if (ComplainAboutVoid) 5081 Diag(Loc, diag::ext_gnu_void_ptr) 5082 << lex->getSourceRange() << rex->getSourceRange(); 5083 if (ComplainAboutFunc) 5084 Diag(Loc, diag::ext_gnu_ptr_func_arith) 5085 << ComplainAboutFunc->getType() 5086 << ComplainAboutFunc->getSourceRange(); 5087 5088 if (CompLHSTy) *CompLHSTy = lex->getType(); 5089 return lex->getType(); 5090 } 5091 5092 // Handle pointer-pointer subtractions. 5093 if (const PointerType *RHSPTy = rex->getType()->getAs<PointerType>()) { 5094 QualType rpointee = RHSPTy->getPointeeType(); 5095 5096 // RHS must be a completely-type object type. 5097 // Handle the GNU void* extension. 5098 if (rpointee->isVoidType()) { 5099 if (getLangOptions().CPlusPlus) { 5100 Diag(Loc, diag::err_typecheck_pointer_arith_void_type) 5101 << lex->getSourceRange() << rex->getSourceRange(); 5102 return QualType(); 5103 } 5104 5105 ComplainAboutVoid = true; 5106 } else if (rpointee->isFunctionType()) { 5107 if (getLangOptions().CPlusPlus) { 5108 Diag(Loc, diag::err_typecheck_pointer_arith_function_type) 5109 << rex->getType() << rex->getSourceRange(); 5110 return QualType(); 5111 } 5112 5113 // GNU extension: arithmetic on pointer to function 5114 if (!ComplainAboutFunc) 5115 ComplainAboutFunc = rex; 5116 } else if (!rpointee->isDependentType() && 5117 RequireCompleteType(Loc, rpointee, 5118 PDiag(diag::err_typecheck_sub_ptr_object) 5119 << rex->getSourceRange() 5120 << rex->getType())) 5121 return QualType(); 5122 5123 if (getLangOptions().CPlusPlus) { 5124 // Pointee types must be the same: C++ [expr.add] 5125 if (!Context.hasSameUnqualifiedType(lpointee, rpointee)) { 5126 Diag(Loc, diag::err_typecheck_sub_ptr_compatible) 5127 << lex->getType() << rex->getType() 5128 << lex->getSourceRange() << rex->getSourceRange(); 5129 return QualType(); 5130 } 5131 } else { 5132 // Pointee types must be compatible C99 6.5.6p3 5133 if (!Context.typesAreCompatible( 5134 Context.getCanonicalType(lpointee).getUnqualifiedType(), 5135 Context.getCanonicalType(rpointee).getUnqualifiedType())) { 5136 Diag(Loc, diag::err_typecheck_sub_ptr_compatible) 5137 << lex->getType() << rex->getType() 5138 << lex->getSourceRange() << rex->getSourceRange(); 5139 return QualType(); 5140 } 5141 } 5142 5143 if (ComplainAboutVoid) 5144 Diag(Loc, diag::ext_gnu_void_ptr) 5145 << lex->getSourceRange() << rex->getSourceRange(); 5146 if (ComplainAboutFunc) 5147 Diag(Loc, diag::ext_gnu_ptr_func_arith) 5148 << ComplainAboutFunc->getType() 5149 << ComplainAboutFunc->getSourceRange(); 5150 5151 if (CompLHSTy) *CompLHSTy = lex->getType(); 5152 return Context.getPointerDiffType(); 5153 } 5154 } 5155 5156 return InvalidOperands(Loc, lex, rex); 5157} 5158 5159// C99 6.5.7 5160QualType Sema::CheckShiftOperands(Expr *&lex, Expr *&rex, SourceLocation Loc, 5161 bool isCompAssign) { 5162 // C99 6.5.7p2: Each of the operands shall have integer type. 5163 if (!lex->getType()->isIntegerType() || !rex->getType()->isIntegerType()) 5164 return InvalidOperands(Loc, lex, rex); 5165 5166 // Vector shifts promote their scalar inputs to vector type. 5167 if (lex->getType()->isVectorType() || rex->getType()->isVectorType()) 5168 return CheckVectorOperands(Loc, lex, rex); 5169 5170 // Shifts don't perform usual arithmetic conversions, they just do integer 5171 // promotions on each operand. C99 6.5.7p3 5172 QualType LHSTy = Context.isPromotableBitField(lex); 5173 if (LHSTy.isNull()) { 5174 LHSTy = lex->getType(); 5175 if (LHSTy->isPromotableIntegerType()) 5176 LHSTy = Context.getPromotedIntegerType(LHSTy); 5177 } 5178 if (!isCompAssign) 5179 ImpCastExprToType(lex, LHSTy, CastExpr::CK_IntegralCast); 5180 5181 UsualUnaryConversions(rex); 5182 5183 // Sanity-check shift operands 5184 llvm::APSInt Right; 5185 // Check right/shifter operand 5186 if (!rex->isValueDependent() && 5187 rex->isIntegerConstantExpr(Right, Context)) { 5188 if (Right.isNegative()) 5189 Diag(Loc, diag::warn_shift_negative) << rex->getSourceRange(); 5190 else { 5191 llvm::APInt LeftBits(Right.getBitWidth(), 5192 Context.getTypeSize(lex->getType())); 5193 if (Right.uge(LeftBits)) 5194 Diag(Loc, diag::warn_shift_gt_typewidth) << rex->getSourceRange(); 5195 } 5196 } 5197 5198 // "The type of the result is that of the promoted left operand." 5199 return LHSTy; 5200} 5201 5202// C99 6.5.8, C++ [expr.rel] 5203QualType Sema::CheckCompareOperands(Expr *&lex, Expr *&rex, SourceLocation Loc, 5204 unsigned OpaqueOpc, bool isRelational) { 5205 BinaryOperator::Opcode Opc = (BinaryOperator::Opcode)OpaqueOpc; 5206 5207 // Handle vector comparisons separately. 5208 if (lex->getType()->isVectorType() || rex->getType()->isVectorType()) 5209 return CheckVectorCompareOperands(lex, rex, Loc, isRelational); 5210 5211 CheckSignCompare(lex, rex, Loc, diag::warn_mixed_sign_comparison, 5212 (Opc == BinaryOperator::EQ || Opc == BinaryOperator::NE)); 5213 5214 // C99 6.5.8p3 / C99 6.5.9p4 5215 if (lex->getType()->isArithmeticType() && rex->getType()->isArithmeticType()) 5216 UsualArithmeticConversions(lex, rex); 5217 else { 5218 UsualUnaryConversions(lex); 5219 UsualUnaryConversions(rex); 5220 } 5221 QualType lType = lex->getType(); 5222 QualType rType = rex->getType(); 5223 5224 if (!lType->isFloatingType() 5225 && !(lType->isBlockPointerType() && isRelational)) { 5226 // For non-floating point types, check for self-comparisons of the form 5227 // x == x, x != x, x < x, etc. These always evaluate to a constant, and 5228 // often indicate logic errors in the program. 5229 // NOTE: Don't warn about comparisons of enum constants. These can arise 5230 // from macro expansions, and are usually quite deliberate. 5231 Expr *LHSStripped = lex->IgnoreParens(); 5232 Expr *RHSStripped = rex->IgnoreParens(); 5233 if (DeclRefExpr* DRL = dyn_cast<DeclRefExpr>(LHSStripped)) 5234 if (DeclRefExpr* DRR = dyn_cast<DeclRefExpr>(RHSStripped)) 5235 if (DRL->getDecl() == DRR->getDecl() && 5236 !isa<EnumConstantDecl>(DRL->getDecl())) 5237 DiagRuntimeBehavior(Loc, PDiag(diag::warn_selfcomparison)); 5238 5239 if (isa<CastExpr>(LHSStripped)) 5240 LHSStripped = LHSStripped->IgnoreParenCasts(); 5241 if (isa<CastExpr>(RHSStripped)) 5242 RHSStripped = RHSStripped->IgnoreParenCasts(); 5243 5244 // Warn about comparisons against a string constant (unless the other 5245 // operand is null), the user probably wants strcmp. 5246 Expr *literalString = 0; 5247 Expr *literalStringStripped = 0; 5248 if ((isa<StringLiteral>(LHSStripped) || isa<ObjCEncodeExpr>(LHSStripped)) && 5249 !RHSStripped->isNullPointerConstant(Context, 5250 Expr::NPC_ValueDependentIsNull)) { 5251 literalString = lex; 5252 literalStringStripped = LHSStripped; 5253 } else if ((isa<StringLiteral>(RHSStripped) || 5254 isa<ObjCEncodeExpr>(RHSStripped)) && 5255 !LHSStripped->isNullPointerConstant(Context, 5256 Expr::NPC_ValueDependentIsNull)) { 5257 literalString = rex; 5258 literalStringStripped = RHSStripped; 5259 } 5260 5261 if (literalString) { 5262 std::string resultComparison; 5263 switch (Opc) { 5264 case BinaryOperator::LT: resultComparison = ") < 0"; break; 5265 case BinaryOperator::GT: resultComparison = ") > 0"; break; 5266 case BinaryOperator::LE: resultComparison = ") <= 0"; break; 5267 case BinaryOperator::GE: resultComparison = ") >= 0"; break; 5268 case BinaryOperator::EQ: resultComparison = ") == 0"; break; 5269 case BinaryOperator::NE: resultComparison = ") != 0"; break; 5270 default: assert(false && "Invalid comparison operator"); 5271 } 5272 5273 DiagRuntimeBehavior(Loc, 5274 PDiag(diag::warn_stringcompare) 5275 << isa<ObjCEncodeExpr>(literalStringStripped) 5276 << literalString->getSourceRange() 5277 << CodeModificationHint::CreateReplacement(SourceRange(Loc), ", ") 5278 << CodeModificationHint::CreateInsertion(lex->getLocStart(), 5279 "strcmp(") 5280 << CodeModificationHint::CreateInsertion( 5281 PP.getLocForEndOfToken(rex->getLocEnd()), 5282 resultComparison)); 5283 } 5284 } 5285 5286 // The result of comparisons is 'bool' in C++, 'int' in C. 5287 QualType ResultTy = getLangOptions().CPlusPlus ? Context.BoolTy:Context.IntTy; 5288 5289 if (isRelational) { 5290 if (lType->isRealType() && rType->isRealType()) 5291 return ResultTy; 5292 } else { 5293 // Check for comparisons of floating point operands using != and ==. 5294 if (lType->isFloatingType() && rType->isFloatingType()) 5295 CheckFloatComparison(Loc,lex,rex); 5296 5297 if (lType->isArithmeticType() && rType->isArithmeticType()) 5298 return ResultTy; 5299 } 5300 5301 bool LHSIsNull = lex->isNullPointerConstant(Context, 5302 Expr::NPC_ValueDependentIsNull); 5303 bool RHSIsNull = rex->isNullPointerConstant(Context, 5304 Expr::NPC_ValueDependentIsNull); 5305 5306 // All of the following pointer related warnings are GCC extensions, except 5307 // when handling null pointer constants. One day, we can consider making them 5308 // errors (when -pedantic-errors is enabled). 5309 if (lType->isPointerType() && rType->isPointerType()) { // C99 6.5.8p2 5310 QualType LCanPointeeTy = 5311 Context.getCanonicalType(lType->getAs<PointerType>()->getPointeeType()); 5312 QualType RCanPointeeTy = 5313 Context.getCanonicalType(rType->getAs<PointerType>()->getPointeeType()); 5314 5315 if (getLangOptions().CPlusPlus) { 5316 if (LCanPointeeTy == RCanPointeeTy) 5317 return ResultTy; 5318 if (!isRelational && 5319 (LCanPointeeTy->isVoidType() || RCanPointeeTy->isVoidType())) { 5320 // Valid unless comparison between non-null pointer and function pointer 5321 // This is a gcc extension compatibility comparison. 5322 if ((LCanPointeeTy->isFunctionType() || RCanPointeeTy->isFunctionType()) 5323 && !LHSIsNull && !RHSIsNull) { 5324 Diag(Loc, diag::ext_typecheck_comparison_of_fptr_to_void) 5325 << lType << rType << lex->getSourceRange() << rex->getSourceRange(); 5326 ImpCastExprToType(rex, lType, CastExpr::CK_BitCast); 5327 return ResultTy; 5328 } 5329 } 5330 // C++ [expr.rel]p2: 5331 // [...] Pointer conversions (4.10) and qualification 5332 // conversions (4.4) are performed on pointer operands (or on 5333 // a pointer operand and a null pointer constant) to bring 5334 // them to their composite pointer type. [...] 5335 // 5336 // C++ [expr.eq]p1 uses the same notion for (in)equality 5337 // comparisons of pointers. 5338 QualType T = FindCompositePointerType(lex, rex); 5339 if (T.isNull()) { 5340 Diag(Loc, diag::err_typecheck_comparison_of_distinct_pointers) 5341 << lType << rType << lex->getSourceRange() << rex->getSourceRange(); 5342 return QualType(); 5343 } 5344 5345 ImpCastExprToType(lex, T, CastExpr::CK_BitCast); 5346 ImpCastExprToType(rex, T, CastExpr::CK_BitCast); 5347 return ResultTy; 5348 } 5349 // C99 6.5.9p2 and C99 6.5.8p2 5350 if (Context.typesAreCompatible(LCanPointeeTy.getUnqualifiedType(), 5351 RCanPointeeTy.getUnqualifiedType())) { 5352 // Valid unless a relational comparison of function pointers 5353 if (isRelational && LCanPointeeTy->isFunctionType()) { 5354 Diag(Loc, diag::ext_typecheck_ordered_comparison_of_function_pointers) 5355 << lType << rType << lex->getSourceRange() << rex->getSourceRange(); 5356 } 5357 } else if (!isRelational && 5358 (LCanPointeeTy->isVoidType() || RCanPointeeTy->isVoidType())) { 5359 // Valid unless comparison between non-null pointer and function pointer 5360 if ((LCanPointeeTy->isFunctionType() || RCanPointeeTy->isFunctionType()) 5361 && !LHSIsNull && !RHSIsNull) { 5362 Diag(Loc, diag::ext_typecheck_comparison_of_fptr_to_void) 5363 << lType << rType << lex->getSourceRange() << rex->getSourceRange(); 5364 } 5365 } else { 5366 // Invalid 5367 Diag(Loc, diag::ext_typecheck_comparison_of_distinct_pointers) 5368 << lType << rType << lex->getSourceRange() << rex->getSourceRange(); 5369 } 5370 if (LCanPointeeTy != RCanPointeeTy) 5371 ImpCastExprToType(rex, lType, CastExpr::CK_BitCast); 5372 return ResultTy; 5373 } 5374 5375 if (getLangOptions().CPlusPlus) { 5376 // Comparison of pointers with null pointer constants and equality 5377 // comparisons of member pointers to null pointer constants. 5378 if (RHSIsNull && 5379 (lType->isPointerType() || 5380 (!isRelational && lType->isMemberPointerType()))) { 5381 ImpCastExprToType(rex, lType, CastExpr::CK_NullToMemberPointer); 5382 return ResultTy; 5383 } 5384 if (LHSIsNull && 5385 (rType->isPointerType() || 5386 (!isRelational && rType->isMemberPointerType()))) { 5387 ImpCastExprToType(lex, rType, CastExpr::CK_NullToMemberPointer); 5388 return ResultTy; 5389 } 5390 5391 // Comparison of member pointers. 5392 if (!isRelational && 5393 lType->isMemberPointerType() && rType->isMemberPointerType()) { 5394 // C++ [expr.eq]p2: 5395 // In addition, pointers to members can be compared, or a pointer to 5396 // member and a null pointer constant. Pointer to member conversions 5397 // (4.11) and qualification conversions (4.4) are performed to bring 5398 // them to a common type. If one operand is a null pointer constant, 5399 // the common type is the type of the other operand. Otherwise, the 5400 // common type is a pointer to member type similar (4.4) to the type 5401 // of one of the operands, with a cv-qualification signature (4.4) 5402 // that is the union of the cv-qualification signatures of the operand 5403 // types. 5404 QualType T = FindCompositePointerType(lex, rex); 5405 if (T.isNull()) { 5406 Diag(Loc, diag::err_typecheck_comparison_of_distinct_pointers) 5407 << lType << rType << lex->getSourceRange() << rex->getSourceRange(); 5408 return QualType(); 5409 } 5410 5411 ImpCastExprToType(lex, T, CastExpr::CK_BitCast); 5412 ImpCastExprToType(rex, T, CastExpr::CK_BitCast); 5413 return ResultTy; 5414 } 5415 5416 // Comparison of nullptr_t with itself. 5417 if (lType->isNullPtrType() && rType->isNullPtrType()) 5418 return ResultTy; 5419 } 5420 5421 // Handle block pointer types. 5422 if (!isRelational && lType->isBlockPointerType() && rType->isBlockPointerType()) { 5423 QualType lpointee = lType->getAs<BlockPointerType>()->getPointeeType(); 5424 QualType rpointee = rType->getAs<BlockPointerType>()->getPointeeType(); 5425 5426 if (!LHSIsNull && !RHSIsNull && 5427 !Context.typesAreCompatible(lpointee, rpointee)) { 5428 Diag(Loc, diag::err_typecheck_comparison_of_distinct_blocks) 5429 << lType << rType << lex->getSourceRange() << rex->getSourceRange(); 5430 } 5431 ImpCastExprToType(rex, lType, CastExpr::CK_BitCast); 5432 return ResultTy; 5433 } 5434 // Allow block pointers to be compared with null pointer constants. 5435 if (!isRelational 5436 && ((lType->isBlockPointerType() && rType->isPointerType()) 5437 || (lType->isPointerType() && rType->isBlockPointerType()))) { 5438 if (!LHSIsNull && !RHSIsNull) { 5439 if (!((rType->isPointerType() && rType->getAs<PointerType>() 5440 ->getPointeeType()->isVoidType()) 5441 || (lType->isPointerType() && lType->getAs<PointerType>() 5442 ->getPointeeType()->isVoidType()))) 5443 Diag(Loc, diag::err_typecheck_comparison_of_distinct_blocks) 5444 << lType << rType << lex->getSourceRange() << rex->getSourceRange(); 5445 } 5446 ImpCastExprToType(rex, lType, CastExpr::CK_BitCast); 5447 return ResultTy; 5448 } 5449 5450 if ((lType->isObjCObjectPointerType() || rType->isObjCObjectPointerType())) { 5451 if (lType->isPointerType() || rType->isPointerType()) { 5452 const PointerType *LPT = lType->getAs<PointerType>(); 5453 const PointerType *RPT = rType->getAs<PointerType>(); 5454 bool LPtrToVoid = LPT ? 5455 Context.getCanonicalType(LPT->getPointeeType())->isVoidType() : false; 5456 bool RPtrToVoid = RPT ? 5457 Context.getCanonicalType(RPT->getPointeeType())->isVoidType() : false; 5458 5459 if (!LPtrToVoid && !RPtrToVoid && 5460 !Context.typesAreCompatible(lType, rType)) { 5461 Diag(Loc, diag::ext_typecheck_comparison_of_distinct_pointers) 5462 << lType << rType << lex->getSourceRange() << rex->getSourceRange(); 5463 } 5464 ImpCastExprToType(rex, lType, CastExpr::CK_BitCast); 5465 return ResultTy; 5466 } 5467 if (lType->isObjCObjectPointerType() && rType->isObjCObjectPointerType()) { 5468 if (!Context.areComparableObjCPointerTypes(lType, rType)) 5469 Diag(Loc, diag::ext_typecheck_comparison_of_distinct_pointers) 5470 << lType << rType << lex->getSourceRange() << rex->getSourceRange(); 5471 ImpCastExprToType(rex, lType, CastExpr::CK_BitCast); 5472 return ResultTy; 5473 } 5474 } 5475 if (lType->isAnyPointerType() && rType->isIntegerType()) { 5476 unsigned DiagID = 0; 5477 if (RHSIsNull) { 5478 if (isRelational) 5479 DiagID = diag::ext_typecheck_ordered_comparison_of_pointer_and_zero; 5480 } else if (isRelational) 5481 DiagID = diag::ext_typecheck_ordered_comparison_of_pointer_integer; 5482 else 5483 DiagID = diag::ext_typecheck_comparison_of_pointer_integer; 5484 5485 if (DiagID) { 5486 Diag(Loc, DiagID) 5487 << lType << rType << lex->getSourceRange() << rex->getSourceRange(); 5488 } 5489 ImpCastExprToType(rex, lType, CastExpr::CK_IntegralToPointer); 5490 return ResultTy; 5491 } 5492 if (lType->isIntegerType() && rType->isAnyPointerType()) { 5493 unsigned DiagID = 0; 5494 if (LHSIsNull) { 5495 if (isRelational) 5496 DiagID = diag::ext_typecheck_ordered_comparison_of_pointer_and_zero; 5497 } else if (isRelational) 5498 DiagID = diag::ext_typecheck_ordered_comparison_of_pointer_integer; 5499 else 5500 DiagID = diag::ext_typecheck_comparison_of_pointer_integer; 5501 5502 if (DiagID) { 5503 Diag(Loc, DiagID) 5504 << lType << rType << lex->getSourceRange() << rex->getSourceRange(); 5505 } 5506 ImpCastExprToType(lex, rType, CastExpr::CK_IntegralToPointer); 5507 return ResultTy; 5508 } 5509 // Handle block pointers. 5510 if (!isRelational && RHSIsNull 5511 && lType->isBlockPointerType() && rType->isIntegerType()) { 5512 ImpCastExprToType(rex, lType, CastExpr::CK_IntegralToPointer); 5513 return ResultTy; 5514 } 5515 if (!isRelational && LHSIsNull 5516 && lType->isIntegerType() && rType->isBlockPointerType()) { 5517 ImpCastExprToType(lex, rType, CastExpr::CK_IntegralToPointer); 5518 return ResultTy; 5519 } 5520 return InvalidOperands(Loc, lex, rex); 5521} 5522 5523/// CheckVectorCompareOperands - vector comparisons are a clang extension that 5524/// operates on extended vector types. Instead of producing an IntTy result, 5525/// like a scalar comparison, a vector comparison produces a vector of integer 5526/// types. 5527QualType Sema::CheckVectorCompareOperands(Expr *&lex, Expr *&rex, 5528 SourceLocation Loc, 5529 bool isRelational) { 5530 // Check to make sure we're operating on vectors of the same type and width, 5531 // Allowing one side to be a scalar of element type. 5532 QualType vType = CheckVectorOperands(Loc, lex, rex); 5533 if (vType.isNull()) 5534 return vType; 5535 5536 QualType lType = lex->getType(); 5537 QualType rType = rex->getType(); 5538 5539 // For non-floating point types, check for self-comparisons of the form 5540 // x == x, x != x, x < x, etc. These always evaluate to a constant, and 5541 // often indicate logic errors in the program. 5542 if (!lType->isFloatingType()) { 5543 if (DeclRefExpr* DRL = dyn_cast<DeclRefExpr>(lex->IgnoreParens())) 5544 if (DeclRefExpr* DRR = dyn_cast<DeclRefExpr>(rex->IgnoreParens())) 5545 if (DRL->getDecl() == DRR->getDecl()) 5546 DiagRuntimeBehavior(Loc, PDiag(diag::warn_selfcomparison)); 5547 } 5548 5549 // Check for comparisons of floating point operands using != and ==. 5550 if (!isRelational && lType->isFloatingType()) { 5551 assert (rType->isFloatingType()); 5552 CheckFloatComparison(Loc,lex,rex); 5553 } 5554 5555 // Return the type for the comparison, which is the same as vector type for 5556 // integer vectors, or an integer type of identical size and number of 5557 // elements for floating point vectors. 5558 if (lType->isIntegerType()) 5559 return lType; 5560 5561 const VectorType *VTy = lType->getAs<VectorType>(); 5562 unsigned TypeSize = Context.getTypeSize(VTy->getElementType()); 5563 if (TypeSize == Context.getTypeSize(Context.IntTy)) 5564 return Context.getExtVectorType(Context.IntTy, VTy->getNumElements()); 5565 if (TypeSize == Context.getTypeSize(Context.LongTy)) 5566 return Context.getExtVectorType(Context.LongTy, VTy->getNumElements()); 5567 5568 assert(TypeSize == Context.getTypeSize(Context.LongLongTy) && 5569 "Unhandled vector element size in vector compare"); 5570 return Context.getExtVectorType(Context.LongLongTy, VTy->getNumElements()); 5571} 5572 5573inline QualType Sema::CheckBitwiseOperands( 5574 Expr *&lex, Expr *&rex, SourceLocation Loc, bool isCompAssign) { 5575 if (lex->getType()->isVectorType() || rex->getType()->isVectorType()) 5576 return CheckVectorOperands(Loc, lex, rex); 5577 5578 QualType compType = UsualArithmeticConversions(lex, rex, isCompAssign); 5579 5580 if (lex->getType()->isIntegerType() && rex->getType()->isIntegerType()) 5581 return compType; 5582 return InvalidOperands(Loc, lex, rex); 5583} 5584 5585inline QualType Sema::CheckLogicalOperands( // C99 6.5.[13,14] 5586 Expr *&lex, Expr *&rex, SourceLocation Loc) { 5587 if (!Context.getLangOptions().CPlusPlus) { 5588 UsualUnaryConversions(lex); 5589 UsualUnaryConversions(rex); 5590 5591 if (!lex->getType()->isScalarType() || !rex->getType()->isScalarType()) 5592 return InvalidOperands(Loc, lex, rex); 5593 5594 return Context.IntTy; 5595 } 5596 5597 // C++ [expr.log.and]p1 5598 // C++ [expr.log.or]p1 5599 // The operands are both implicitly converted to type bool (clause 4). 5600 StandardConversionSequence LHS; 5601 if (!IsStandardConversion(lex, Context.BoolTy, 5602 /*InOverloadResolution=*/false, LHS)) 5603 return InvalidOperands(Loc, lex, rex); 5604 5605 if (PerformImplicitConversion(lex, Context.BoolTy, LHS, 5606 AA_Passing, /*IgnoreBaseAccess=*/false)) 5607 return InvalidOperands(Loc, lex, rex); 5608 5609 StandardConversionSequence RHS; 5610 if (!IsStandardConversion(rex, Context.BoolTy, 5611 /*InOverloadResolution=*/false, RHS)) 5612 return InvalidOperands(Loc, lex, rex); 5613 5614 if (PerformImplicitConversion(rex, Context.BoolTy, RHS, 5615 AA_Passing, /*IgnoreBaseAccess=*/false)) 5616 return InvalidOperands(Loc, lex, rex); 5617 5618 // C++ [expr.log.and]p2 5619 // C++ [expr.log.or]p2 5620 // The result is a bool. 5621 return Context.BoolTy; 5622} 5623 5624/// IsReadonlyProperty - Verify that otherwise a valid l-value expression 5625/// is a read-only property; return true if so. A readonly property expression 5626/// depends on various declarations and thus must be treated specially. 5627/// 5628static bool IsReadonlyProperty(Expr *E, Sema &S) { 5629 if (E->getStmtClass() == Expr::ObjCPropertyRefExprClass) { 5630 const ObjCPropertyRefExpr* PropExpr = cast<ObjCPropertyRefExpr>(E); 5631 if (ObjCPropertyDecl *PDecl = PropExpr->getProperty()) { 5632 QualType BaseType = PropExpr->getBase()->getType(); 5633 if (const ObjCObjectPointerType *OPT = 5634 BaseType->getAsObjCInterfacePointerType()) 5635 if (ObjCInterfaceDecl *IFace = OPT->getInterfaceDecl()) 5636 if (S.isPropertyReadonly(PDecl, IFace)) 5637 return true; 5638 } 5639 } 5640 return false; 5641} 5642 5643/// CheckForModifiableLvalue - Verify that E is a modifiable lvalue. If not, 5644/// emit an error and return true. If so, return false. 5645static bool CheckForModifiableLvalue(Expr *E, SourceLocation Loc, Sema &S) { 5646 SourceLocation OrigLoc = Loc; 5647 Expr::isModifiableLvalueResult IsLV = E->isModifiableLvalue(S.Context, 5648 &Loc); 5649 if (IsLV == Expr::MLV_Valid && IsReadonlyProperty(E, S)) 5650 IsLV = Expr::MLV_ReadonlyProperty; 5651 if (IsLV == Expr::MLV_Valid) 5652 return false; 5653 5654 unsigned Diag = 0; 5655 bool NeedType = false; 5656 switch (IsLV) { // C99 6.5.16p2 5657 default: assert(0 && "Unknown result from isModifiableLvalue!"); 5658 case Expr::MLV_ConstQualified: Diag = diag::err_typecheck_assign_const; break; 5659 case Expr::MLV_ArrayType: 5660 Diag = diag::err_typecheck_array_not_modifiable_lvalue; 5661 NeedType = true; 5662 break; 5663 case Expr::MLV_NotObjectType: 5664 Diag = diag::err_typecheck_non_object_not_modifiable_lvalue; 5665 NeedType = true; 5666 break; 5667 case Expr::MLV_LValueCast: 5668 Diag = diag::err_typecheck_lvalue_casts_not_supported; 5669 break; 5670 case Expr::MLV_InvalidExpression: 5671 Diag = diag::err_typecheck_expression_not_modifiable_lvalue; 5672 break; 5673 case Expr::MLV_IncompleteType: 5674 case Expr::MLV_IncompleteVoidType: 5675 return S.RequireCompleteType(Loc, E->getType(), 5676 PDiag(diag::err_typecheck_incomplete_type_not_modifiable_lvalue) 5677 << E->getSourceRange()); 5678 case Expr::MLV_DuplicateVectorComponents: 5679 Diag = diag::err_typecheck_duplicate_vector_components_not_mlvalue; 5680 break; 5681 case Expr::MLV_NotBlockQualified: 5682 Diag = diag::err_block_decl_ref_not_modifiable_lvalue; 5683 break; 5684 case Expr::MLV_ReadonlyProperty: 5685 Diag = diag::error_readonly_property_assignment; 5686 break; 5687 case Expr::MLV_NoSetterProperty: 5688 Diag = diag::error_nosetter_property_assignment; 5689 break; 5690 case Expr::MLV_SubObjCPropertySetting: 5691 Diag = diag::error_no_subobject_property_setting; 5692 break; 5693 } 5694 5695 SourceRange Assign; 5696 if (Loc != OrigLoc) 5697 Assign = SourceRange(OrigLoc, OrigLoc); 5698 if (NeedType) 5699 S.Diag(Loc, Diag) << E->getType() << E->getSourceRange() << Assign; 5700 else 5701 S.Diag(Loc, Diag) << E->getSourceRange() << Assign; 5702 return true; 5703} 5704 5705 5706 5707// C99 6.5.16.1 5708QualType Sema::CheckAssignmentOperands(Expr *LHS, Expr *&RHS, 5709 SourceLocation Loc, 5710 QualType CompoundType) { 5711 // Verify that LHS is a modifiable lvalue, and emit error if not. 5712 if (CheckForModifiableLvalue(LHS, Loc, *this)) 5713 return QualType(); 5714 5715 QualType LHSType = LHS->getType(); 5716 QualType RHSType = CompoundType.isNull() ? RHS->getType() : CompoundType; 5717 5718 AssignConvertType ConvTy; 5719 if (CompoundType.isNull()) { 5720 // Simple assignment "x = y". 5721 ConvTy = CheckSingleAssignmentConstraints(LHSType, RHS); 5722 // Special case of NSObject attributes on c-style pointer types. 5723 if (ConvTy == IncompatiblePointer && 5724 ((Context.isObjCNSObjectType(LHSType) && 5725 RHSType->isObjCObjectPointerType()) || 5726 (Context.isObjCNSObjectType(RHSType) && 5727 LHSType->isObjCObjectPointerType()))) 5728 ConvTy = Compatible; 5729 5730 // If the RHS is a unary plus or minus, check to see if they = and + are 5731 // right next to each other. If so, the user may have typo'd "x =+ 4" 5732 // instead of "x += 4". 5733 Expr *RHSCheck = RHS; 5734 if (ImplicitCastExpr *ICE = dyn_cast<ImplicitCastExpr>(RHSCheck)) 5735 RHSCheck = ICE->getSubExpr(); 5736 if (UnaryOperator *UO = dyn_cast<UnaryOperator>(RHSCheck)) { 5737 if ((UO->getOpcode() == UnaryOperator::Plus || 5738 UO->getOpcode() == UnaryOperator::Minus) && 5739 Loc.isFileID() && UO->getOperatorLoc().isFileID() && 5740 // Only if the two operators are exactly adjacent. 5741 Loc.getFileLocWithOffset(1) == UO->getOperatorLoc() && 5742 // And there is a space or other character before the subexpr of the 5743 // unary +/-. We don't want to warn on "x=-1". 5744 Loc.getFileLocWithOffset(2) != UO->getSubExpr()->getLocStart() && 5745 UO->getSubExpr()->getLocStart().isFileID()) { 5746 Diag(Loc, diag::warn_not_compound_assign) 5747 << (UO->getOpcode() == UnaryOperator::Plus ? "+" : "-") 5748 << SourceRange(UO->getOperatorLoc(), UO->getOperatorLoc()); 5749 } 5750 } 5751 } else { 5752 // Compound assignment "x += y" 5753 ConvTy = CheckAssignmentConstraints(LHSType, RHSType); 5754 } 5755 5756 if (DiagnoseAssignmentResult(ConvTy, Loc, LHSType, RHSType, 5757 RHS, AA_Assigning)) 5758 return QualType(); 5759 5760 // C99 6.5.16p3: The type of an assignment expression is the type of the 5761 // left operand unless the left operand has qualified type, in which case 5762 // it is the unqualified version of the type of the left operand. 5763 // C99 6.5.16.1p2: In simple assignment, the value of the right operand 5764 // is converted to the type of the assignment expression (above). 5765 // C++ 5.17p1: the type of the assignment expression is that of its left 5766 // operand. 5767 return LHSType.getUnqualifiedType(); 5768} 5769 5770// C99 6.5.17 5771QualType Sema::CheckCommaOperands(Expr *LHS, Expr *&RHS, SourceLocation Loc) { 5772 // Comma performs lvalue conversion (C99 6.3.2.1), but not unary conversions. 5773 DefaultFunctionArrayConversion(RHS); 5774 5775 // FIXME: Check that RHS type is complete in C mode (it's legal for it to be 5776 // incomplete in C++). 5777 5778 return RHS->getType(); 5779} 5780 5781/// CheckIncrementDecrementOperand - unlike most "Check" methods, this routine 5782/// doesn't need to call UsualUnaryConversions or UsualArithmeticConversions. 5783QualType Sema::CheckIncrementDecrementOperand(Expr *Op, SourceLocation OpLoc, 5784 bool isInc) { 5785 if (Op->isTypeDependent()) 5786 return Context.DependentTy; 5787 5788 QualType ResType = Op->getType(); 5789 assert(!ResType.isNull() && "no type for increment/decrement expression"); 5790 5791 if (getLangOptions().CPlusPlus && ResType->isBooleanType()) { 5792 // Decrement of bool is not allowed. 5793 if (!isInc) { 5794 Diag(OpLoc, diag::err_decrement_bool) << Op->getSourceRange(); 5795 return QualType(); 5796 } 5797 // Increment of bool sets it to true, but is deprecated. 5798 Diag(OpLoc, diag::warn_increment_bool) << Op->getSourceRange(); 5799 } else if (ResType->isRealType()) { 5800 // OK! 5801 } else if (ResType->isAnyPointerType()) { 5802 QualType PointeeTy = ResType->getPointeeType(); 5803 5804 // C99 6.5.2.4p2, 6.5.6p2 5805 if (PointeeTy->isVoidType()) { 5806 if (getLangOptions().CPlusPlus) { 5807 Diag(OpLoc, diag::err_typecheck_pointer_arith_void_type) 5808 << Op->getSourceRange(); 5809 return QualType(); 5810 } 5811 5812 // Pointer to void is a GNU extension in C. 5813 Diag(OpLoc, diag::ext_gnu_void_ptr) << Op->getSourceRange(); 5814 } else if (PointeeTy->isFunctionType()) { 5815 if (getLangOptions().CPlusPlus) { 5816 Diag(OpLoc, diag::err_typecheck_pointer_arith_function_type) 5817 << Op->getType() << Op->getSourceRange(); 5818 return QualType(); 5819 } 5820 5821 Diag(OpLoc, diag::ext_gnu_ptr_func_arith) 5822 << ResType << Op->getSourceRange(); 5823 } else if (RequireCompleteType(OpLoc, PointeeTy, 5824 PDiag(diag::err_typecheck_arithmetic_incomplete_type) 5825 << Op->getSourceRange() 5826 << ResType)) 5827 return QualType(); 5828 // Diagnose bad cases where we step over interface counts. 5829 else if (PointeeTy->isObjCInterfaceType() && LangOpts.ObjCNonFragileABI) { 5830 Diag(OpLoc, diag::err_arithmetic_nonfragile_interface) 5831 << PointeeTy << Op->getSourceRange(); 5832 return QualType(); 5833 } 5834 } else if (ResType->isAnyComplexType()) { 5835 // C99 does not support ++/-- on complex types, we allow as an extension. 5836 Diag(OpLoc, diag::ext_integer_increment_complex) 5837 << ResType << Op->getSourceRange(); 5838 } else { 5839 Diag(OpLoc, diag::err_typecheck_illegal_increment_decrement) 5840 << ResType << int(isInc) << Op->getSourceRange(); 5841 return QualType(); 5842 } 5843 // At this point, we know we have a real, complex or pointer type. 5844 // Now make sure the operand is a modifiable lvalue. 5845 if (CheckForModifiableLvalue(Op, OpLoc, *this)) 5846 return QualType(); 5847 return ResType; 5848} 5849 5850/// getPrimaryDecl - Helper function for CheckAddressOfOperand(). 5851/// This routine allows us to typecheck complex/recursive expressions 5852/// where the declaration is needed for type checking. We only need to 5853/// handle cases when the expression references a function designator 5854/// or is an lvalue. Here are some examples: 5855/// - &(x) => x 5856/// - &*****f => f for f a function designator. 5857/// - &s.xx => s 5858/// - &s.zz[1].yy -> s, if zz is an array 5859/// - *(x + 1) -> x, if x is an array 5860/// - &"123"[2] -> 0 5861/// - & __real__ x -> x 5862static NamedDecl *getPrimaryDecl(Expr *E) { 5863 switch (E->getStmtClass()) { 5864 case Stmt::DeclRefExprClass: 5865 return cast<DeclRefExpr>(E)->getDecl(); 5866 case Stmt::MemberExprClass: 5867 // If this is an arrow operator, the address is an offset from 5868 // the base's value, so the object the base refers to is 5869 // irrelevant. 5870 if (cast<MemberExpr>(E)->isArrow()) 5871 return 0; 5872 // Otherwise, the expression refers to a part of the base 5873 return getPrimaryDecl(cast<MemberExpr>(E)->getBase()); 5874 case Stmt::ArraySubscriptExprClass: { 5875 // FIXME: This code shouldn't be necessary! We should catch the implicit 5876 // promotion of register arrays earlier. 5877 Expr* Base = cast<ArraySubscriptExpr>(E)->getBase(); 5878 if (ImplicitCastExpr* ICE = dyn_cast<ImplicitCastExpr>(Base)) { 5879 if (ICE->getSubExpr()->getType()->isArrayType()) 5880 return getPrimaryDecl(ICE->getSubExpr()); 5881 } 5882 return 0; 5883 } 5884 case Stmt::UnaryOperatorClass: { 5885 UnaryOperator *UO = cast<UnaryOperator>(E); 5886 5887 switch(UO->getOpcode()) { 5888 case UnaryOperator::Real: 5889 case UnaryOperator::Imag: 5890 case UnaryOperator::Extension: 5891 return getPrimaryDecl(UO->getSubExpr()); 5892 default: 5893 return 0; 5894 } 5895 } 5896 case Stmt::ParenExprClass: 5897 return getPrimaryDecl(cast<ParenExpr>(E)->getSubExpr()); 5898 case Stmt::ImplicitCastExprClass: 5899 // If the result of an implicit cast is an l-value, we care about 5900 // the sub-expression; otherwise, the result here doesn't matter. 5901 return getPrimaryDecl(cast<ImplicitCastExpr>(E)->getSubExpr()); 5902 default: 5903 return 0; 5904 } 5905} 5906 5907/// CheckAddressOfOperand - The operand of & must be either a function 5908/// designator or an lvalue designating an object. If it is an lvalue, the 5909/// object cannot be declared with storage class register or be a bit field. 5910/// Note: The usual conversions are *not* applied to the operand of the & 5911/// operator (C99 6.3.2.1p[2-4]), and its result is never an lvalue. 5912/// In C++, the operand might be an overloaded function name, in which case 5913/// we allow the '&' but retain the overloaded-function type. 5914QualType Sema::CheckAddressOfOperand(Expr *op, SourceLocation OpLoc) { 5915 // Make sure to ignore parentheses in subsequent checks 5916 op = op->IgnoreParens(); 5917 5918 if (op->isTypeDependent()) 5919 return Context.DependentTy; 5920 5921 if (getLangOptions().C99) { 5922 // Implement C99-only parts of addressof rules. 5923 if (UnaryOperator* uOp = dyn_cast<UnaryOperator>(op)) { 5924 if (uOp->getOpcode() == UnaryOperator::Deref) 5925 // Per C99 6.5.3.2, the address of a deref always returns a valid result 5926 // (assuming the deref expression is valid). 5927 return uOp->getSubExpr()->getType(); 5928 } 5929 // Technically, there should be a check for array subscript 5930 // expressions here, but the result of one is always an lvalue anyway. 5931 } 5932 NamedDecl *dcl = getPrimaryDecl(op); 5933 Expr::isLvalueResult lval = op->isLvalue(Context); 5934 5935 MemberExpr *ME = dyn_cast<MemberExpr>(op); 5936 if (lval == Expr::LV_MemberFunction && ME && 5937 isa<CXXMethodDecl>(ME->getMemberDecl())) { 5938 ValueDecl *dcl = cast<MemberExpr>(op)->getMemberDecl(); 5939 // &f where f is a member of the current object, or &o.f, or &p->f 5940 // All these are not allowed, and we need to catch them before the dcl 5941 // branch of the if, below. 5942 Diag(OpLoc, diag::err_unqualified_pointer_member_function) 5943 << dcl; 5944 // FIXME: Improve this diagnostic and provide a fixit. 5945 5946 // Now recover by acting as if the function had been accessed qualified. 5947 return Context.getMemberPointerType(op->getType(), 5948 Context.getTypeDeclType(cast<RecordDecl>(dcl->getDeclContext())) 5949 .getTypePtr()); 5950 } else if (lval != Expr::LV_Valid && lval != Expr::LV_IncompleteVoidType) { 5951 // C99 6.5.3.2p1 5952 // The operand must be either an l-value or a function designator 5953 if (!op->getType()->isFunctionType()) { 5954 // FIXME: emit more specific diag... 5955 Diag(OpLoc, diag::err_typecheck_invalid_lvalue_addrof) 5956 << op->getSourceRange(); 5957 return QualType(); 5958 } 5959 } else if (op->getBitField()) { // C99 6.5.3.2p1 5960 // The operand cannot be a bit-field 5961 Diag(OpLoc, diag::err_typecheck_address_of) 5962 << "bit-field" << op->getSourceRange(); 5963 return QualType(); 5964 } else if (isa<ExtVectorElementExpr>(op) || (isa<ArraySubscriptExpr>(op) && 5965 cast<ArraySubscriptExpr>(op)->getBase()->getType()->isVectorType())){ 5966 // The operand cannot be an element of a vector 5967 Diag(OpLoc, diag::err_typecheck_address_of) 5968 << "vector element" << op->getSourceRange(); 5969 return QualType(); 5970 } else if (isa<ObjCPropertyRefExpr>(op)) { 5971 // cannot take address of a property expression. 5972 Diag(OpLoc, diag::err_typecheck_address_of) 5973 << "property expression" << op->getSourceRange(); 5974 return QualType(); 5975 } else if (ConditionalOperator *CO = dyn_cast<ConditionalOperator>(op)) { 5976 // FIXME: Can LHS ever be null here? 5977 if (!CheckAddressOfOperand(CO->getTrueExpr(), OpLoc).isNull()) 5978 return CheckAddressOfOperand(CO->getFalseExpr(), OpLoc); 5979 } else if (isa<UnresolvedLookupExpr>(op)) { 5980 return Context.OverloadTy; 5981 } else if (dcl) { // C99 6.5.3.2p1 5982 // We have an lvalue with a decl. Make sure the decl is not declared 5983 // with the register storage-class specifier. 5984 if (const VarDecl *vd = dyn_cast<VarDecl>(dcl)) { 5985 if (vd->getStorageClass() == VarDecl::Register) { 5986 Diag(OpLoc, diag::err_typecheck_address_of) 5987 << "register variable" << op->getSourceRange(); 5988 return QualType(); 5989 } 5990 } else if (isa<FunctionTemplateDecl>(dcl)) { 5991 return Context.OverloadTy; 5992 } else if (FieldDecl *FD = dyn_cast<FieldDecl>(dcl)) { 5993 // Okay: we can take the address of a field. 5994 // Could be a pointer to member, though, if there is an explicit 5995 // scope qualifier for the class. 5996 if (isa<DeclRefExpr>(op) && cast<DeclRefExpr>(op)->getQualifier()) { 5997 DeclContext *Ctx = dcl->getDeclContext(); 5998 if (Ctx && Ctx->isRecord()) { 5999 if (FD->getType()->isReferenceType()) { 6000 Diag(OpLoc, 6001 diag::err_cannot_form_pointer_to_member_of_reference_type) 6002 << FD->getDeclName() << FD->getType(); 6003 return QualType(); 6004 } 6005 6006 return Context.getMemberPointerType(op->getType(), 6007 Context.getTypeDeclType(cast<RecordDecl>(Ctx)).getTypePtr()); 6008 } 6009 } 6010 } else if (CXXMethodDecl *MD = dyn_cast<CXXMethodDecl>(dcl)) { 6011 // Okay: we can take the address of a function. 6012 // As above. 6013 if (isa<DeclRefExpr>(op) && cast<DeclRefExpr>(op)->getQualifier() && 6014 MD->isInstance()) 6015 return Context.getMemberPointerType(op->getType(), 6016 Context.getTypeDeclType(MD->getParent()).getTypePtr()); 6017 } else if (!isa<FunctionDecl>(dcl)) 6018 assert(0 && "Unknown/unexpected decl type"); 6019 } 6020 6021 if (lval == Expr::LV_IncompleteVoidType) { 6022 // Taking the address of a void variable is technically illegal, but we 6023 // allow it in cases which are otherwise valid. 6024 // Example: "extern void x; void* y = &x;". 6025 Diag(OpLoc, diag::ext_typecheck_addrof_void) << op->getSourceRange(); 6026 } 6027 6028 // If the operand has type "type", the result has type "pointer to type". 6029 return Context.getPointerType(op->getType()); 6030} 6031 6032QualType Sema::CheckIndirectionOperand(Expr *Op, SourceLocation OpLoc) { 6033 if (Op->isTypeDependent()) 6034 return Context.DependentTy; 6035 6036 UsualUnaryConversions(Op); 6037 QualType Ty = Op->getType(); 6038 6039 // Note that per both C89 and C99, this is always legal, even if ptype is an 6040 // incomplete type or void. It would be possible to warn about dereferencing 6041 // a void pointer, but it's completely well-defined, and such a warning is 6042 // unlikely to catch any mistakes. 6043 if (const PointerType *PT = Ty->getAs<PointerType>()) 6044 return PT->getPointeeType(); 6045 6046 if (const ObjCObjectPointerType *OPT = Ty->getAs<ObjCObjectPointerType>()) 6047 return OPT->getPointeeType(); 6048 6049 Diag(OpLoc, diag::err_typecheck_indirection_requires_pointer) 6050 << Ty << Op->getSourceRange(); 6051 return QualType(); 6052} 6053 6054static inline BinaryOperator::Opcode ConvertTokenKindToBinaryOpcode( 6055 tok::TokenKind Kind) { 6056 BinaryOperator::Opcode Opc; 6057 switch (Kind) { 6058 default: assert(0 && "Unknown binop!"); 6059 case tok::periodstar: Opc = BinaryOperator::PtrMemD; break; 6060 case tok::arrowstar: Opc = BinaryOperator::PtrMemI; break; 6061 case tok::star: Opc = BinaryOperator::Mul; break; 6062 case tok::slash: Opc = BinaryOperator::Div; break; 6063 case tok::percent: Opc = BinaryOperator::Rem; break; 6064 case tok::plus: Opc = BinaryOperator::Add; break; 6065 case tok::minus: Opc = BinaryOperator::Sub; break; 6066 case tok::lessless: Opc = BinaryOperator::Shl; break; 6067 case tok::greatergreater: Opc = BinaryOperator::Shr; break; 6068 case tok::lessequal: Opc = BinaryOperator::LE; break; 6069 case tok::less: Opc = BinaryOperator::LT; break; 6070 case tok::greaterequal: Opc = BinaryOperator::GE; break; 6071 case tok::greater: Opc = BinaryOperator::GT; break; 6072 case tok::exclaimequal: Opc = BinaryOperator::NE; break; 6073 case tok::equalequal: Opc = BinaryOperator::EQ; break; 6074 case tok::amp: Opc = BinaryOperator::And; break; 6075 case tok::caret: Opc = BinaryOperator::Xor; break; 6076 case tok::pipe: Opc = BinaryOperator::Or; break; 6077 case tok::ampamp: Opc = BinaryOperator::LAnd; break; 6078 case tok::pipepipe: Opc = BinaryOperator::LOr; break; 6079 case tok::equal: Opc = BinaryOperator::Assign; break; 6080 case tok::starequal: Opc = BinaryOperator::MulAssign; break; 6081 case tok::slashequal: Opc = BinaryOperator::DivAssign; break; 6082 case tok::percentequal: Opc = BinaryOperator::RemAssign; break; 6083 case tok::plusequal: Opc = BinaryOperator::AddAssign; break; 6084 case tok::minusequal: Opc = BinaryOperator::SubAssign; break; 6085 case tok::lesslessequal: Opc = BinaryOperator::ShlAssign; break; 6086 case tok::greatergreaterequal: Opc = BinaryOperator::ShrAssign; break; 6087 case tok::ampequal: Opc = BinaryOperator::AndAssign; break; 6088 case tok::caretequal: Opc = BinaryOperator::XorAssign; break; 6089 case tok::pipeequal: Opc = BinaryOperator::OrAssign; break; 6090 case tok::comma: Opc = BinaryOperator::Comma; break; 6091 } 6092 return Opc; 6093} 6094 6095static inline UnaryOperator::Opcode ConvertTokenKindToUnaryOpcode( 6096 tok::TokenKind Kind) { 6097 UnaryOperator::Opcode Opc; 6098 switch (Kind) { 6099 default: assert(0 && "Unknown unary op!"); 6100 case tok::plusplus: Opc = UnaryOperator::PreInc; break; 6101 case tok::minusminus: Opc = UnaryOperator::PreDec; break; 6102 case tok::amp: Opc = UnaryOperator::AddrOf; break; 6103 case tok::star: Opc = UnaryOperator::Deref; break; 6104 case tok::plus: Opc = UnaryOperator::Plus; break; 6105 case tok::minus: Opc = UnaryOperator::Minus; break; 6106 case tok::tilde: Opc = UnaryOperator::Not; break; 6107 case tok::exclaim: Opc = UnaryOperator::LNot; break; 6108 case tok::kw___real: Opc = UnaryOperator::Real; break; 6109 case tok::kw___imag: Opc = UnaryOperator::Imag; break; 6110 case tok::kw___extension__: Opc = UnaryOperator::Extension; break; 6111 } 6112 return Opc; 6113} 6114 6115/// CreateBuiltinBinOp - Creates a new built-in binary operation with 6116/// operator @p Opc at location @c TokLoc. This routine only supports 6117/// built-in operations; ActOnBinOp handles overloaded operators. 6118Action::OwningExprResult Sema::CreateBuiltinBinOp(SourceLocation OpLoc, 6119 unsigned Op, 6120 Expr *lhs, Expr *rhs) { 6121 QualType ResultTy; // Result type of the binary operator. 6122 BinaryOperator::Opcode Opc = (BinaryOperator::Opcode)Op; 6123 // The following two variables are used for compound assignment operators 6124 QualType CompLHSTy; // Type of LHS after promotions for computation 6125 QualType CompResultTy; // Type of computation result 6126 6127 switch (Opc) { 6128 case BinaryOperator::Assign: 6129 ResultTy = CheckAssignmentOperands(lhs, rhs, OpLoc, QualType()); 6130 break; 6131 case BinaryOperator::PtrMemD: 6132 case BinaryOperator::PtrMemI: 6133 ResultTy = CheckPointerToMemberOperands(lhs, rhs, OpLoc, 6134 Opc == BinaryOperator::PtrMemI); 6135 break; 6136 case BinaryOperator::Mul: 6137 case BinaryOperator::Div: 6138 ResultTy = CheckMultiplyDivideOperands(lhs, rhs, OpLoc, false, 6139 Opc == BinaryOperator::Div); 6140 break; 6141 case BinaryOperator::Rem: 6142 ResultTy = CheckRemainderOperands(lhs, rhs, OpLoc); 6143 break; 6144 case BinaryOperator::Add: 6145 ResultTy = CheckAdditionOperands(lhs, rhs, OpLoc); 6146 break; 6147 case BinaryOperator::Sub: 6148 ResultTy = CheckSubtractionOperands(lhs, rhs, OpLoc); 6149 break; 6150 case BinaryOperator::Shl: 6151 case BinaryOperator::Shr: 6152 ResultTy = CheckShiftOperands(lhs, rhs, OpLoc); 6153 break; 6154 case BinaryOperator::LE: 6155 case BinaryOperator::LT: 6156 case BinaryOperator::GE: 6157 case BinaryOperator::GT: 6158 ResultTy = CheckCompareOperands(lhs, rhs, OpLoc, Opc, true); 6159 break; 6160 case BinaryOperator::EQ: 6161 case BinaryOperator::NE: 6162 ResultTy = CheckCompareOperands(lhs, rhs, OpLoc, Opc, false); 6163 break; 6164 case BinaryOperator::And: 6165 case BinaryOperator::Xor: 6166 case BinaryOperator::Or: 6167 ResultTy = CheckBitwiseOperands(lhs, rhs, OpLoc); 6168 break; 6169 case BinaryOperator::LAnd: 6170 case BinaryOperator::LOr: 6171 ResultTy = CheckLogicalOperands(lhs, rhs, OpLoc); 6172 break; 6173 case BinaryOperator::MulAssign: 6174 case BinaryOperator::DivAssign: 6175 CompResultTy = CheckMultiplyDivideOperands(lhs, rhs, OpLoc, true, 6176 Opc == BinaryOperator::DivAssign); 6177 CompLHSTy = CompResultTy; 6178 if (!CompResultTy.isNull()) 6179 ResultTy = CheckAssignmentOperands(lhs, rhs, OpLoc, CompResultTy); 6180 break; 6181 case BinaryOperator::RemAssign: 6182 CompResultTy = CheckRemainderOperands(lhs, rhs, OpLoc, true); 6183 CompLHSTy = CompResultTy; 6184 if (!CompResultTy.isNull()) 6185 ResultTy = CheckAssignmentOperands(lhs, rhs, OpLoc, CompResultTy); 6186 break; 6187 case BinaryOperator::AddAssign: 6188 CompResultTy = CheckAdditionOperands(lhs, rhs, OpLoc, &CompLHSTy); 6189 if (!CompResultTy.isNull()) 6190 ResultTy = CheckAssignmentOperands(lhs, rhs, OpLoc, CompResultTy); 6191 break; 6192 case BinaryOperator::SubAssign: 6193 CompResultTy = CheckSubtractionOperands(lhs, rhs, OpLoc, &CompLHSTy); 6194 if (!CompResultTy.isNull()) 6195 ResultTy = CheckAssignmentOperands(lhs, rhs, OpLoc, CompResultTy); 6196 break; 6197 case BinaryOperator::ShlAssign: 6198 case BinaryOperator::ShrAssign: 6199 CompResultTy = CheckShiftOperands(lhs, rhs, OpLoc, true); 6200 CompLHSTy = CompResultTy; 6201 if (!CompResultTy.isNull()) 6202 ResultTy = CheckAssignmentOperands(lhs, rhs, OpLoc, CompResultTy); 6203 break; 6204 case BinaryOperator::AndAssign: 6205 case BinaryOperator::XorAssign: 6206 case BinaryOperator::OrAssign: 6207 CompResultTy = CheckBitwiseOperands(lhs, rhs, OpLoc, true); 6208 CompLHSTy = CompResultTy; 6209 if (!CompResultTy.isNull()) 6210 ResultTy = CheckAssignmentOperands(lhs, rhs, OpLoc, CompResultTy); 6211 break; 6212 case BinaryOperator::Comma: 6213 ResultTy = CheckCommaOperands(lhs, rhs, OpLoc); 6214 break; 6215 } 6216 if (ResultTy.isNull()) 6217 return ExprError(); 6218 if (CompResultTy.isNull()) 6219 return Owned(new (Context) BinaryOperator(lhs, rhs, Opc, ResultTy, OpLoc)); 6220 else 6221 return Owned(new (Context) CompoundAssignOperator(lhs, rhs, Opc, ResultTy, 6222 CompLHSTy, CompResultTy, 6223 OpLoc)); 6224} 6225 6226/// SuggestParentheses - Emit a diagnostic together with a fixit hint that wraps 6227/// ParenRange in parentheses. 6228static void SuggestParentheses(Sema &Self, SourceLocation Loc, 6229 const PartialDiagnostic &PD, 6230 SourceRange ParenRange, 6231 const PartialDiagnostic &SecondPD = PartialDiagnostic(0), 6232 SourceRange SecondParenRange = SourceRange()) { 6233 SourceLocation EndLoc = Self.PP.getLocForEndOfToken(ParenRange.getEnd()); 6234 if (!ParenRange.getEnd().isFileID() || EndLoc.isInvalid()) { 6235 // We can't display the parentheses, so just dig the 6236 // warning/error and return. 6237 Self.Diag(Loc, PD); 6238 return; 6239 } 6240 6241 Self.Diag(Loc, PD) 6242 << CodeModificationHint::CreateInsertion(ParenRange.getBegin(), "(") 6243 << CodeModificationHint::CreateInsertion(EndLoc, ")"); 6244 6245 if (!SecondPD.getDiagID()) 6246 return; 6247 6248 EndLoc = Self.PP.getLocForEndOfToken(SecondParenRange.getEnd()); 6249 if (!SecondParenRange.getEnd().isFileID() || EndLoc.isInvalid()) { 6250 // We can't display the parentheses, so just dig the 6251 // warning/error and return. 6252 Self.Diag(Loc, SecondPD); 6253 return; 6254 } 6255 6256 Self.Diag(Loc, SecondPD) 6257 << CodeModificationHint::CreateInsertion(SecondParenRange.getBegin(), "(") 6258 << CodeModificationHint::CreateInsertion(EndLoc, ")"); 6259} 6260 6261/// DiagnoseBitwisePrecedence - Emit a warning when bitwise and comparison 6262/// operators are mixed in a way that suggests that the programmer forgot that 6263/// comparison operators have higher precedence. The most typical example of 6264/// such code is "flags & 0x0020 != 0", which is equivalent to "flags & 1". 6265static void DiagnoseBitwisePrecedence(Sema &Self, BinaryOperator::Opcode Opc, 6266 SourceLocation OpLoc,Expr *lhs,Expr *rhs){ 6267 typedef BinaryOperator BinOp; 6268 BinOp::Opcode lhsopc = static_cast<BinOp::Opcode>(-1), 6269 rhsopc = static_cast<BinOp::Opcode>(-1); 6270 if (BinOp *BO = dyn_cast<BinOp>(lhs)) 6271 lhsopc = BO->getOpcode(); 6272 if (BinOp *BO = dyn_cast<BinOp>(rhs)) 6273 rhsopc = BO->getOpcode(); 6274 6275 // Subs are not binary operators. 6276 if (lhsopc == -1 && rhsopc == -1) 6277 return; 6278 6279 // Bitwise operations are sometimes used as eager logical ops. 6280 // Don't diagnose this. 6281 if ((BinOp::isComparisonOp(lhsopc) || BinOp::isBitwiseOp(lhsopc)) && 6282 (BinOp::isComparisonOp(rhsopc) || BinOp::isBitwiseOp(rhsopc))) 6283 return; 6284 6285 if (BinOp::isComparisonOp(lhsopc)) 6286 SuggestParentheses(Self, OpLoc, 6287 PDiag(diag::warn_precedence_bitwise_rel) 6288 << SourceRange(lhs->getLocStart(), OpLoc) 6289 << BinOp::getOpcodeStr(Opc) << BinOp::getOpcodeStr(lhsopc), 6290 lhs->getSourceRange(), 6291 PDiag(diag::note_precedence_bitwise_first) 6292 << BinOp::getOpcodeStr(Opc), 6293 SourceRange(cast<BinOp>(lhs)->getRHS()->getLocStart(), rhs->getLocEnd())); 6294 else if (BinOp::isComparisonOp(rhsopc)) 6295 SuggestParentheses(Self, OpLoc, 6296 PDiag(diag::warn_precedence_bitwise_rel) 6297 << SourceRange(OpLoc, rhs->getLocEnd()) 6298 << BinOp::getOpcodeStr(Opc) << BinOp::getOpcodeStr(rhsopc), 6299 rhs->getSourceRange(), 6300 PDiag(diag::note_precedence_bitwise_first) 6301 << BinOp::getOpcodeStr(Opc), 6302 SourceRange(lhs->getLocEnd(), cast<BinOp>(rhs)->getLHS()->getLocStart())); 6303} 6304 6305/// DiagnoseBinOpPrecedence - Emit warnings for expressions with tricky 6306/// precedence. This currently diagnoses only "arg1 'bitwise' arg2 'eq' arg3". 6307/// But it could also warn about arg1 && arg2 || arg3, as GCC 4.3+ does. 6308static void DiagnoseBinOpPrecedence(Sema &Self, BinaryOperator::Opcode Opc, 6309 SourceLocation OpLoc, Expr *lhs, Expr *rhs){ 6310 if (BinaryOperator::isBitwiseOp(Opc)) 6311 DiagnoseBitwisePrecedence(Self, Opc, OpLoc, lhs, rhs); 6312} 6313 6314// Binary Operators. 'Tok' is the token for the operator. 6315Action::OwningExprResult Sema::ActOnBinOp(Scope *S, SourceLocation TokLoc, 6316 tok::TokenKind Kind, 6317 ExprArg LHS, ExprArg RHS) { 6318 BinaryOperator::Opcode Opc = ConvertTokenKindToBinaryOpcode(Kind); 6319 Expr *lhs = LHS.takeAs<Expr>(), *rhs = RHS.takeAs<Expr>(); 6320 6321 assert((lhs != 0) && "ActOnBinOp(): missing left expression"); 6322 assert((rhs != 0) && "ActOnBinOp(): missing right expression"); 6323 6324 // Emit warnings for tricky precedence issues, e.g. "bitfield & 0x4 == 0" 6325 DiagnoseBinOpPrecedence(*this, Opc, TokLoc, lhs, rhs); 6326 6327 return BuildBinOp(S, TokLoc, Opc, lhs, rhs); 6328} 6329 6330Action::OwningExprResult Sema::BuildBinOp(Scope *S, SourceLocation OpLoc, 6331 BinaryOperator::Opcode Opc, 6332 Expr *lhs, Expr *rhs) { 6333 if (getLangOptions().CPlusPlus && 6334 (lhs->getType()->isOverloadableType() || 6335 rhs->getType()->isOverloadableType())) { 6336 // Find all of the overloaded operators visible from this 6337 // point. We perform both an operator-name lookup from the local 6338 // scope and an argument-dependent lookup based on the types of 6339 // the arguments. 6340 FunctionSet Functions; 6341 OverloadedOperatorKind OverOp = BinaryOperator::getOverloadedOperator(Opc); 6342 if (OverOp != OO_None) { 6343 if (S) 6344 LookupOverloadedOperatorName(OverOp, S, lhs->getType(), rhs->getType(), 6345 Functions); 6346 Expr *Args[2] = { lhs, rhs }; 6347 DeclarationName OpName 6348 = Context.DeclarationNames.getCXXOperatorName(OverOp); 6349 ArgumentDependentLookup(OpName, /*Operator*/true, Args, 2, Functions); 6350 } 6351 6352 // Build the (potentially-overloaded, potentially-dependent) 6353 // binary operation. 6354 return CreateOverloadedBinOp(OpLoc, Opc, Functions, lhs, rhs); 6355 } 6356 6357 // Build a built-in binary operation. 6358 return CreateBuiltinBinOp(OpLoc, Opc, lhs, rhs); 6359} 6360 6361Action::OwningExprResult Sema::CreateBuiltinUnaryOp(SourceLocation OpLoc, 6362 unsigned OpcIn, 6363 ExprArg InputArg) { 6364 UnaryOperator::Opcode Opc = static_cast<UnaryOperator::Opcode>(OpcIn); 6365 6366 // FIXME: Input is modified below, but InputArg is not updated appropriately. 6367 Expr *Input = (Expr *)InputArg.get(); 6368 QualType resultType; 6369 switch (Opc) { 6370 case UnaryOperator::OffsetOf: 6371 assert(false && "Invalid unary operator"); 6372 break; 6373 6374 case UnaryOperator::PreInc: 6375 case UnaryOperator::PreDec: 6376 case UnaryOperator::PostInc: 6377 case UnaryOperator::PostDec: 6378 resultType = CheckIncrementDecrementOperand(Input, OpLoc, 6379 Opc == UnaryOperator::PreInc || 6380 Opc == UnaryOperator::PostInc); 6381 break; 6382 case UnaryOperator::AddrOf: 6383 resultType = CheckAddressOfOperand(Input, OpLoc); 6384 break; 6385 case UnaryOperator::Deref: 6386 DefaultFunctionArrayConversion(Input); 6387 resultType = CheckIndirectionOperand(Input, OpLoc); 6388 break; 6389 case UnaryOperator::Plus: 6390 case UnaryOperator::Minus: 6391 UsualUnaryConversions(Input); 6392 resultType = Input->getType(); 6393 if (resultType->isDependentType()) 6394 break; 6395 if (resultType->isArithmeticType()) // C99 6.5.3.3p1 6396 break; 6397 else if (getLangOptions().CPlusPlus && // C++ [expr.unary.op]p6-7 6398 resultType->isEnumeralType()) 6399 break; 6400 else if (getLangOptions().CPlusPlus && // C++ [expr.unary.op]p6 6401 Opc == UnaryOperator::Plus && 6402 resultType->isPointerType()) 6403 break; 6404 6405 return ExprError(Diag(OpLoc, diag::err_typecheck_unary_expr) 6406 << resultType << Input->getSourceRange()); 6407 case UnaryOperator::Not: // bitwise complement 6408 UsualUnaryConversions(Input); 6409 resultType = Input->getType(); 6410 if (resultType->isDependentType()) 6411 break; 6412 // C99 6.5.3.3p1. We allow complex int and float as a GCC extension. 6413 if (resultType->isComplexType() || resultType->isComplexIntegerType()) 6414 // C99 does not support '~' for complex conjugation. 6415 Diag(OpLoc, diag::ext_integer_complement_complex) 6416 << resultType << Input->getSourceRange(); 6417 else if (!resultType->isIntegerType()) 6418 return ExprError(Diag(OpLoc, diag::err_typecheck_unary_expr) 6419 << resultType << Input->getSourceRange()); 6420 break; 6421 case UnaryOperator::LNot: // logical negation 6422 // Unlike +/-/~, integer promotions aren't done here (C99 6.5.3.3p5). 6423 DefaultFunctionArrayConversion(Input); 6424 resultType = Input->getType(); 6425 if (resultType->isDependentType()) 6426 break; 6427 if (!resultType->isScalarType()) // C99 6.5.3.3p1 6428 return ExprError(Diag(OpLoc, diag::err_typecheck_unary_expr) 6429 << resultType << Input->getSourceRange()); 6430 // LNot always has type int. C99 6.5.3.3p5. 6431 // In C++, it's bool. C++ 5.3.1p8 6432 resultType = getLangOptions().CPlusPlus ? Context.BoolTy : Context.IntTy; 6433 break; 6434 case UnaryOperator::Real: 6435 case UnaryOperator::Imag: 6436 resultType = CheckRealImagOperand(Input, OpLoc, Opc == UnaryOperator::Real); 6437 break; 6438 case UnaryOperator::Extension: 6439 resultType = Input->getType(); 6440 break; 6441 } 6442 if (resultType.isNull()) 6443 return ExprError(); 6444 6445 InputArg.release(); 6446 return Owned(new (Context) UnaryOperator(Input, Opc, resultType, OpLoc)); 6447} 6448 6449Action::OwningExprResult Sema::BuildUnaryOp(Scope *S, SourceLocation OpLoc, 6450 UnaryOperator::Opcode Opc, 6451 ExprArg input) { 6452 Expr *Input = (Expr*)input.get(); 6453 if (getLangOptions().CPlusPlus && Input->getType()->isOverloadableType() && 6454 Opc != UnaryOperator::Extension) { 6455 // Find all of the overloaded operators visible from this 6456 // point. We perform both an operator-name lookup from the local 6457 // scope and an argument-dependent lookup based on the types of 6458 // the arguments. 6459 FunctionSet Functions; 6460 OverloadedOperatorKind OverOp = UnaryOperator::getOverloadedOperator(Opc); 6461 if (OverOp != OO_None) { 6462 if (S) 6463 LookupOverloadedOperatorName(OverOp, S, Input->getType(), QualType(), 6464 Functions); 6465 DeclarationName OpName 6466 = Context.DeclarationNames.getCXXOperatorName(OverOp); 6467 ArgumentDependentLookup(OpName, /*Operator*/true, &Input, 1, Functions); 6468 } 6469 6470 return CreateOverloadedUnaryOp(OpLoc, Opc, Functions, move(input)); 6471 } 6472 6473 return CreateBuiltinUnaryOp(OpLoc, Opc, move(input)); 6474} 6475 6476// Unary Operators. 'Tok' is the token for the operator. 6477Action::OwningExprResult Sema::ActOnUnaryOp(Scope *S, SourceLocation OpLoc, 6478 tok::TokenKind Op, ExprArg input) { 6479 return BuildUnaryOp(S, OpLoc, ConvertTokenKindToUnaryOpcode(Op), move(input)); 6480} 6481 6482/// ActOnAddrLabel - Parse the GNU address of label extension: "&&foo". 6483Sema::OwningExprResult Sema::ActOnAddrLabel(SourceLocation OpLoc, 6484 SourceLocation LabLoc, 6485 IdentifierInfo *LabelII) { 6486 // Look up the record for this label identifier. 6487 LabelStmt *&LabelDecl = getLabelMap()[LabelII]; 6488 6489 // If we haven't seen this label yet, create a forward reference. It 6490 // will be validated and/or cleaned up in ActOnFinishFunctionBody. 6491 if (LabelDecl == 0) 6492 LabelDecl = new (Context) LabelStmt(LabLoc, LabelII, 0); 6493 6494 // Create the AST node. The address of a label always has type 'void*'. 6495 return Owned(new (Context) AddrLabelExpr(OpLoc, LabLoc, LabelDecl, 6496 Context.getPointerType(Context.VoidTy))); 6497} 6498 6499Sema::OwningExprResult 6500Sema::ActOnStmtExpr(SourceLocation LPLoc, StmtArg substmt, 6501 SourceLocation RPLoc) { // "({..})" 6502 Stmt *SubStmt = static_cast<Stmt*>(substmt.get()); 6503 assert(SubStmt && isa<CompoundStmt>(SubStmt) && "Invalid action invocation!"); 6504 CompoundStmt *Compound = cast<CompoundStmt>(SubStmt); 6505 6506 bool isFileScope = getCurFunctionOrMethodDecl() == 0; 6507 if (isFileScope) 6508 return ExprError(Diag(LPLoc, diag::err_stmtexpr_file_scope)); 6509 6510 // FIXME: there are a variety of strange constraints to enforce here, for 6511 // example, it is not possible to goto into a stmt expression apparently. 6512 // More semantic analysis is needed. 6513 6514 // If there are sub stmts in the compound stmt, take the type of the last one 6515 // as the type of the stmtexpr. 6516 QualType Ty = Context.VoidTy; 6517 6518 if (!Compound->body_empty()) { 6519 Stmt *LastStmt = Compound->body_back(); 6520 // If LastStmt is a label, skip down through into the body. 6521 while (LabelStmt *Label = dyn_cast<LabelStmt>(LastStmt)) 6522 LastStmt = Label->getSubStmt(); 6523 6524 if (Expr *LastExpr = dyn_cast<Expr>(LastStmt)) 6525 Ty = LastExpr->getType(); 6526 } 6527 6528 // FIXME: Check that expression type is complete/non-abstract; statement 6529 // expressions are not lvalues. 6530 6531 substmt.release(); 6532 return Owned(new (Context) StmtExpr(Compound, Ty, LPLoc, RPLoc)); 6533} 6534 6535Sema::OwningExprResult Sema::ActOnBuiltinOffsetOf(Scope *S, 6536 SourceLocation BuiltinLoc, 6537 SourceLocation TypeLoc, 6538 TypeTy *argty, 6539 OffsetOfComponent *CompPtr, 6540 unsigned NumComponents, 6541 SourceLocation RPLoc) { 6542 // FIXME: This function leaks all expressions in the offset components on 6543 // error. 6544 // FIXME: Preserve type source info. 6545 QualType ArgTy = GetTypeFromParser(argty); 6546 assert(!ArgTy.isNull() && "Missing type argument!"); 6547 6548 bool Dependent = ArgTy->isDependentType(); 6549 6550 // We must have at least one component that refers to the type, and the first 6551 // one is known to be a field designator. Verify that the ArgTy represents 6552 // a struct/union/class. 6553 if (!Dependent && !ArgTy->isRecordType()) 6554 return ExprError(Diag(TypeLoc, diag::err_offsetof_record_type) << ArgTy); 6555 6556 // FIXME: Type must be complete per C99 7.17p3 because a declaring a variable 6557 // with an incomplete type would be illegal. 6558 6559 // Otherwise, create a null pointer as the base, and iteratively process 6560 // the offsetof designators. 6561 QualType ArgTyPtr = Context.getPointerType(ArgTy); 6562 Expr* Res = new (Context) ImplicitValueInitExpr(ArgTyPtr); 6563 Res = new (Context) UnaryOperator(Res, UnaryOperator::Deref, 6564 ArgTy, SourceLocation()); 6565 6566 // offsetof with non-identifier designators (e.g. "offsetof(x, a.b[c])") are a 6567 // GCC extension, diagnose them. 6568 // FIXME: This diagnostic isn't actually visible because the location is in 6569 // a system header! 6570 if (NumComponents != 1) 6571 Diag(BuiltinLoc, diag::ext_offsetof_extended_field_designator) 6572 << SourceRange(CompPtr[1].LocStart, CompPtr[NumComponents-1].LocEnd); 6573 6574 if (!Dependent) { 6575 bool DidWarnAboutNonPOD = false; 6576 6577 if (RequireCompleteType(TypeLoc, Res->getType(), 6578 diag::err_offsetof_incomplete_type)) 6579 return ExprError(); 6580 6581 // FIXME: Dependent case loses a lot of information here. And probably 6582 // leaks like a sieve. 6583 for (unsigned i = 0; i != NumComponents; ++i) { 6584 const OffsetOfComponent &OC = CompPtr[i]; 6585 if (OC.isBrackets) { 6586 // Offset of an array sub-field. TODO: Should we allow vector elements? 6587 const ArrayType *AT = Context.getAsArrayType(Res->getType()); 6588 if (!AT) { 6589 Res->Destroy(Context); 6590 return ExprError(Diag(OC.LocEnd, diag::err_offsetof_array_type) 6591 << Res->getType()); 6592 } 6593 6594 // FIXME: C++: Verify that operator[] isn't overloaded. 6595 6596 // Promote the array so it looks more like a normal array subscript 6597 // expression. 6598 DefaultFunctionArrayConversion(Res); 6599 6600 // C99 6.5.2.1p1 6601 Expr *Idx = static_cast<Expr*>(OC.U.E); 6602 // FIXME: Leaks Res 6603 if (!Idx->isTypeDependent() && !Idx->getType()->isIntegerType()) 6604 return ExprError(Diag(Idx->getLocStart(), 6605 diag::err_typecheck_subscript_not_integer) 6606 << Idx->getSourceRange()); 6607 6608 Res = new (Context) ArraySubscriptExpr(Res, Idx, AT->getElementType(), 6609 OC.LocEnd); 6610 continue; 6611 } 6612 6613 const RecordType *RC = Res->getType()->getAs<RecordType>(); 6614 if (!RC) { 6615 Res->Destroy(Context); 6616 return ExprError(Diag(OC.LocEnd, diag::err_offsetof_record_type) 6617 << Res->getType()); 6618 } 6619 6620 // Get the decl corresponding to this. 6621 RecordDecl *RD = RC->getDecl(); 6622 if (CXXRecordDecl *CRD = dyn_cast<CXXRecordDecl>(RD)) { 6623 if (!CRD->isPOD() && !DidWarnAboutNonPOD && 6624 DiagRuntimeBehavior(BuiltinLoc, 6625 PDiag(diag::warn_offsetof_non_pod_type) 6626 << SourceRange(CompPtr[0].LocStart, OC.LocEnd) 6627 << Res->getType())) 6628 DidWarnAboutNonPOD = true; 6629 } 6630 6631 LookupResult R(*this, OC.U.IdentInfo, OC.LocStart, LookupMemberName); 6632 LookupQualifiedName(R, RD); 6633 6634 FieldDecl *MemberDecl = R.getAsSingle<FieldDecl>(); 6635 // FIXME: Leaks Res 6636 if (!MemberDecl) 6637 return ExprError(Diag(BuiltinLoc, diag::err_no_member) 6638 << OC.U.IdentInfo << RD << SourceRange(OC.LocStart, OC.LocEnd)); 6639 6640 // FIXME: C++: Verify that MemberDecl isn't a static field. 6641 // FIXME: Verify that MemberDecl isn't a bitfield. 6642 if (cast<RecordDecl>(MemberDecl->getDeclContext())->isAnonymousStructOrUnion()) { 6643 Res = BuildAnonymousStructUnionMemberReference( 6644 OC.LocEnd, MemberDecl, Res, OC.LocEnd).takeAs<Expr>(); 6645 } else { 6646 PerformObjectMemberConversion(Res, MemberDecl); 6647 // MemberDecl->getType() doesn't get the right qualifiers, but it 6648 // doesn't matter here. 6649 Res = new (Context) MemberExpr(Res, false, MemberDecl, OC.LocEnd, 6650 MemberDecl->getType().getNonReferenceType()); 6651 } 6652 } 6653 } 6654 6655 return Owned(new (Context) UnaryOperator(Res, UnaryOperator::OffsetOf, 6656 Context.getSizeType(), BuiltinLoc)); 6657} 6658 6659 6660Sema::OwningExprResult Sema::ActOnTypesCompatibleExpr(SourceLocation BuiltinLoc, 6661 TypeTy *arg1,TypeTy *arg2, 6662 SourceLocation RPLoc) { 6663 // FIXME: Preserve type source info. 6664 QualType argT1 = GetTypeFromParser(arg1); 6665 QualType argT2 = GetTypeFromParser(arg2); 6666 6667 assert((!argT1.isNull() && !argT2.isNull()) && "Missing type argument(s)"); 6668 6669 if (getLangOptions().CPlusPlus) { 6670 Diag(BuiltinLoc, diag::err_types_compatible_p_in_cplusplus) 6671 << SourceRange(BuiltinLoc, RPLoc); 6672 return ExprError(); 6673 } 6674 6675 return Owned(new (Context) TypesCompatibleExpr(Context.IntTy, BuiltinLoc, 6676 argT1, argT2, RPLoc)); 6677} 6678 6679Sema::OwningExprResult Sema::ActOnChooseExpr(SourceLocation BuiltinLoc, 6680 ExprArg cond, 6681 ExprArg expr1, ExprArg expr2, 6682 SourceLocation RPLoc) { 6683 Expr *CondExpr = static_cast<Expr*>(cond.get()); 6684 Expr *LHSExpr = static_cast<Expr*>(expr1.get()); 6685 Expr *RHSExpr = static_cast<Expr*>(expr2.get()); 6686 6687 assert((CondExpr && LHSExpr && RHSExpr) && "Missing type argument(s)"); 6688 6689 QualType resType; 6690 bool ValueDependent = false; 6691 if (CondExpr->isTypeDependent() || CondExpr->isValueDependent()) { 6692 resType = Context.DependentTy; 6693 ValueDependent = true; 6694 } else { 6695 // The conditional expression is required to be a constant expression. 6696 llvm::APSInt condEval(32); 6697 SourceLocation ExpLoc; 6698 if (!CondExpr->isIntegerConstantExpr(condEval, Context, &ExpLoc)) 6699 return ExprError(Diag(ExpLoc, 6700 diag::err_typecheck_choose_expr_requires_constant) 6701 << CondExpr->getSourceRange()); 6702 6703 // If the condition is > zero, then the AST type is the same as the LSHExpr. 6704 resType = condEval.getZExtValue() ? LHSExpr->getType() : RHSExpr->getType(); 6705 ValueDependent = condEval.getZExtValue() ? LHSExpr->isValueDependent() 6706 : RHSExpr->isValueDependent(); 6707 } 6708 6709 cond.release(); expr1.release(); expr2.release(); 6710 return Owned(new (Context) ChooseExpr(BuiltinLoc, CondExpr, LHSExpr, RHSExpr, 6711 resType, RPLoc, 6712 resType->isDependentType(), 6713 ValueDependent)); 6714} 6715 6716//===----------------------------------------------------------------------===// 6717// Clang Extensions. 6718//===----------------------------------------------------------------------===// 6719 6720/// ActOnBlockStart - This callback is invoked when a block literal is started. 6721void Sema::ActOnBlockStart(SourceLocation CaretLoc, Scope *BlockScope) { 6722 // Analyze block parameters. 6723 BlockSemaInfo *BSI = new BlockSemaInfo(); 6724 6725 // Add BSI to CurBlock. 6726 BSI->PrevBlockInfo = CurBlock; 6727 CurBlock = BSI; 6728 6729 BSI->ReturnType = QualType(); 6730 BSI->TheScope = BlockScope; 6731 BSI->hasBlockDeclRefExprs = false; 6732 BSI->hasPrototype = false; 6733 BSI->SavedFunctionNeedsScopeChecking = CurFunctionNeedsScopeChecking; 6734 CurFunctionNeedsScopeChecking = false; 6735 6736 BSI->TheDecl = BlockDecl::Create(Context, CurContext, CaretLoc); 6737 CurContext->addDecl(BSI->TheDecl); 6738 PushDeclContext(BlockScope, BSI->TheDecl); 6739} 6740 6741void Sema::ActOnBlockArguments(Declarator &ParamInfo, Scope *CurScope) { 6742 assert(ParamInfo.getIdentifier()==0 && "block-id should have no identifier!"); 6743 6744 if (ParamInfo.getNumTypeObjects() == 0 6745 || ParamInfo.getTypeObject(0).Kind != DeclaratorChunk::Function) { 6746 ProcessDeclAttributes(CurScope, CurBlock->TheDecl, ParamInfo); 6747 QualType T = GetTypeForDeclarator(ParamInfo, CurScope); 6748 6749 if (T->isArrayType()) { 6750 Diag(ParamInfo.getSourceRange().getBegin(), 6751 diag::err_block_returns_array); 6752 return; 6753 } 6754 6755 // The parameter list is optional, if there was none, assume (). 6756 if (!T->isFunctionType()) 6757 T = Context.getFunctionType(T, NULL, 0, 0, 0); 6758 6759 CurBlock->hasPrototype = true; 6760 CurBlock->isVariadic = false; 6761 // Check for a valid sentinel attribute on this block. 6762 if (CurBlock->TheDecl->getAttr<SentinelAttr>()) { 6763 Diag(ParamInfo.getAttributes()->getLoc(), 6764 diag::warn_attribute_sentinel_not_variadic) << 1; 6765 // FIXME: remove the attribute. 6766 } 6767 QualType RetTy = T.getTypePtr()->getAs<FunctionType>()->getResultType(); 6768 6769 // Do not allow returning a objc interface by-value. 6770 if (RetTy->isObjCInterfaceType()) { 6771 Diag(ParamInfo.getSourceRange().getBegin(), 6772 diag::err_object_cannot_be_passed_returned_by_value) << 0 << RetTy; 6773 return; 6774 } 6775 return; 6776 } 6777 6778 // Analyze arguments to block. 6779 assert(ParamInfo.getTypeObject(0).Kind == DeclaratorChunk::Function && 6780 "Not a function declarator!"); 6781 DeclaratorChunk::FunctionTypeInfo &FTI = ParamInfo.getTypeObject(0).Fun; 6782 6783 CurBlock->hasPrototype = FTI.hasPrototype; 6784 CurBlock->isVariadic = true; 6785 6786 // Check for C99 6.7.5.3p10 - foo(void) is a non-varargs function that takes 6787 // no arguments, not a function that takes a single void argument. 6788 if (FTI.hasPrototype && 6789 FTI.NumArgs == 1 && !FTI.isVariadic && FTI.ArgInfo[0].Ident == 0 && 6790 (!FTI.ArgInfo[0].Param.getAs<ParmVarDecl>()->getType().getCVRQualifiers()&& 6791 FTI.ArgInfo[0].Param.getAs<ParmVarDecl>()->getType()->isVoidType())) { 6792 // empty arg list, don't push any params. 6793 CurBlock->isVariadic = false; 6794 } else if (FTI.hasPrototype) { 6795 for (unsigned i = 0, e = FTI.NumArgs; i != e; ++i) 6796 CurBlock->Params.push_back(FTI.ArgInfo[i].Param.getAs<ParmVarDecl>()); 6797 CurBlock->isVariadic = FTI.isVariadic; 6798 } 6799 CurBlock->TheDecl->setParams(Context, CurBlock->Params.data(), 6800 CurBlock->Params.size()); 6801 CurBlock->TheDecl->setIsVariadic(CurBlock->isVariadic); 6802 ProcessDeclAttributes(CurScope, CurBlock->TheDecl, ParamInfo); 6803 for (BlockDecl::param_iterator AI = CurBlock->TheDecl->param_begin(), 6804 E = CurBlock->TheDecl->param_end(); AI != E; ++AI) 6805 // If this has an identifier, add it to the scope stack. 6806 if ((*AI)->getIdentifier()) 6807 PushOnScopeChains(*AI, CurBlock->TheScope); 6808 6809 // Check for a valid sentinel attribute on this block. 6810 if (!CurBlock->isVariadic && 6811 CurBlock->TheDecl->getAttr<SentinelAttr>()) { 6812 Diag(ParamInfo.getAttributes()->getLoc(), 6813 diag::warn_attribute_sentinel_not_variadic) << 1; 6814 // FIXME: remove the attribute. 6815 } 6816 6817 // Analyze the return type. 6818 QualType T = GetTypeForDeclarator(ParamInfo, CurScope); 6819 QualType RetTy = T->getAs<FunctionType>()->getResultType(); 6820 6821 // Do not allow returning a objc interface by-value. 6822 if (RetTy->isObjCInterfaceType()) { 6823 Diag(ParamInfo.getSourceRange().getBegin(), 6824 diag::err_object_cannot_be_passed_returned_by_value) << 0 << RetTy; 6825 } else if (!RetTy->isDependentType()) 6826 CurBlock->ReturnType = RetTy; 6827} 6828 6829/// ActOnBlockError - If there is an error parsing a block, this callback 6830/// is invoked to pop the information about the block from the action impl. 6831void Sema::ActOnBlockError(SourceLocation CaretLoc, Scope *CurScope) { 6832 // Ensure that CurBlock is deleted. 6833 llvm::OwningPtr<BlockSemaInfo> CC(CurBlock); 6834 6835 CurFunctionNeedsScopeChecking = CurBlock->SavedFunctionNeedsScopeChecking; 6836 6837 // Pop off CurBlock, handle nested blocks. 6838 PopDeclContext(); 6839 CurBlock = CurBlock->PrevBlockInfo; 6840 // FIXME: Delete the ParmVarDecl objects as well??? 6841} 6842 6843/// ActOnBlockStmtExpr - This is called when the body of a block statement 6844/// literal was successfully completed. ^(int x){...} 6845Sema::OwningExprResult Sema::ActOnBlockStmtExpr(SourceLocation CaretLoc, 6846 StmtArg body, Scope *CurScope) { 6847 // If blocks are disabled, emit an error. 6848 if (!LangOpts.Blocks) 6849 Diag(CaretLoc, diag::err_blocks_disable); 6850 6851 // Ensure that CurBlock is deleted. 6852 llvm::OwningPtr<BlockSemaInfo> BSI(CurBlock); 6853 6854 PopDeclContext(); 6855 6856 // Pop off CurBlock, handle nested blocks. 6857 CurBlock = CurBlock->PrevBlockInfo; 6858 6859 QualType RetTy = Context.VoidTy; 6860 if (!BSI->ReturnType.isNull()) 6861 RetTy = BSI->ReturnType; 6862 6863 llvm::SmallVector<QualType, 8> ArgTypes; 6864 for (unsigned i = 0, e = BSI->Params.size(); i != e; ++i) 6865 ArgTypes.push_back(BSI->Params[i]->getType()); 6866 6867 bool NoReturn = BSI->TheDecl->getAttr<NoReturnAttr>(); 6868 QualType BlockTy; 6869 if (!BSI->hasPrototype) 6870 BlockTy = Context.getFunctionType(RetTy, 0, 0, false, 0, false, false, 0, 0, 6871 NoReturn); 6872 else 6873 BlockTy = Context.getFunctionType(RetTy, ArgTypes.data(), ArgTypes.size(), 6874 BSI->isVariadic, 0, false, false, 0, 0, 6875 NoReturn); 6876 6877 // FIXME: Check that return/parameter types are complete/non-abstract 6878 DiagnoseUnusedParameters(BSI->Params.begin(), BSI->Params.end()); 6879 BlockTy = Context.getBlockPointerType(BlockTy); 6880 6881 // If needed, diagnose invalid gotos and switches in the block. 6882 if (CurFunctionNeedsScopeChecking) 6883 DiagnoseInvalidJumps(static_cast<CompoundStmt*>(body.get())); 6884 CurFunctionNeedsScopeChecking = BSI->SavedFunctionNeedsScopeChecking; 6885 6886 BSI->TheDecl->setBody(body.takeAs<CompoundStmt>()); 6887 AnalysisContext AC(BSI->TheDecl); 6888 CheckFallThroughForBlock(BlockTy, BSI->TheDecl->getBody(), AC); 6889 CheckUnreachable(AC); 6890 return Owned(new (Context) BlockExpr(BSI->TheDecl, BlockTy, 6891 BSI->hasBlockDeclRefExprs)); 6892} 6893 6894Sema::OwningExprResult Sema::ActOnVAArg(SourceLocation BuiltinLoc, 6895 ExprArg expr, TypeTy *type, 6896 SourceLocation RPLoc) { 6897 QualType T = GetTypeFromParser(type); 6898 Expr *E = static_cast<Expr*>(expr.get()); 6899 Expr *OrigExpr = E; 6900 6901 InitBuiltinVaListType(); 6902 6903 // Get the va_list type 6904 QualType VaListType = Context.getBuiltinVaListType(); 6905 if (VaListType->isArrayType()) { 6906 // Deal with implicit array decay; for example, on x86-64, 6907 // va_list is an array, but it's supposed to decay to 6908 // a pointer for va_arg. 6909 VaListType = Context.getArrayDecayedType(VaListType); 6910 // Make sure the input expression also decays appropriately. 6911 UsualUnaryConversions(E); 6912 } else { 6913 // Otherwise, the va_list argument must be an l-value because 6914 // it is modified by va_arg. 6915 if (!E->isTypeDependent() && 6916 CheckForModifiableLvalue(E, BuiltinLoc, *this)) 6917 return ExprError(); 6918 } 6919 6920 if (!E->isTypeDependent() && 6921 !Context.hasSameType(VaListType, E->getType())) { 6922 return ExprError(Diag(E->getLocStart(), 6923 diag::err_first_argument_to_va_arg_not_of_type_va_list) 6924 << OrigExpr->getType() << E->getSourceRange()); 6925 } 6926 6927 // FIXME: Check that type is complete/non-abstract 6928 // FIXME: Warn if a non-POD type is passed in. 6929 6930 expr.release(); 6931 return Owned(new (Context) VAArgExpr(BuiltinLoc, E, T.getNonReferenceType(), 6932 RPLoc)); 6933} 6934 6935Sema::OwningExprResult Sema::ActOnGNUNullExpr(SourceLocation TokenLoc) { 6936 // The type of __null will be int or long, depending on the size of 6937 // pointers on the target. 6938 QualType Ty; 6939 if (Context.Target.getPointerWidth(0) == Context.Target.getIntWidth()) 6940 Ty = Context.IntTy; 6941 else 6942 Ty = Context.LongTy; 6943 6944 return Owned(new (Context) GNUNullExpr(Ty, TokenLoc)); 6945} 6946 6947static void 6948MakeObjCStringLiteralCodeModificationHint(Sema& SemaRef, 6949 QualType DstType, 6950 Expr *SrcExpr, 6951 CodeModificationHint &Hint) { 6952 if (!SemaRef.getLangOptions().ObjC1) 6953 return; 6954 6955 const ObjCObjectPointerType *PT = DstType->getAs<ObjCObjectPointerType>(); 6956 if (!PT) 6957 return; 6958 6959 // Check if the destination is of type 'id'. 6960 if (!PT->isObjCIdType()) { 6961 // Check if the destination is the 'NSString' interface. 6962 const ObjCInterfaceDecl *ID = PT->getInterfaceDecl(); 6963 if (!ID || !ID->getIdentifier()->isStr("NSString")) 6964 return; 6965 } 6966 6967 // Strip off any parens and casts. 6968 StringLiteral *SL = dyn_cast<StringLiteral>(SrcExpr->IgnoreParenCasts()); 6969 if (!SL || SL->isWide()) 6970 return; 6971 6972 Hint = CodeModificationHint::CreateInsertion(SL->getLocStart(), "@"); 6973} 6974 6975bool Sema::DiagnoseAssignmentResult(AssignConvertType ConvTy, 6976 SourceLocation Loc, 6977 QualType DstType, QualType SrcType, 6978 Expr *SrcExpr, AssignmentAction Action) { 6979 // Decode the result (notice that AST's are still created for extensions). 6980 bool isInvalid = false; 6981 unsigned DiagKind; 6982 CodeModificationHint Hint; 6983 6984 switch (ConvTy) { 6985 default: assert(0 && "Unknown conversion type"); 6986 case Compatible: return false; 6987 case PointerToInt: 6988 DiagKind = diag::ext_typecheck_convert_pointer_int; 6989 break; 6990 case IntToPointer: 6991 DiagKind = diag::ext_typecheck_convert_int_pointer; 6992 break; 6993 case IncompatiblePointer: 6994 MakeObjCStringLiteralCodeModificationHint(*this, DstType, SrcExpr, Hint); 6995 DiagKind = diag::ext_typecheck_convert_incompatible_pointer; 6996 break; 6997 case IncompatiblePointerSign: 6998 DiagKind = diag::ext_typecheck_convert_incompatible_pointer_sign; 6999 break; 7000 case FunctionVoidPointer: 7001 DiagKind = diag::ext_typecheck_convert_pointer_void_func; 7002 break; 7003 case CompatiblePointerDiscardsQualifiers: 7004 // If the qualifiers lost were because we were applying the 7005 // (deprecated) C++ conversion from a string literal to a char* 7006 // (or wchar_t*), then there was no error (C++ 4.2p2). FIXME: 7007 // Ideally, this check would be performed in 7008 // CheckPointerTypesForAssignment. However, that would require a 7009 // bit of refactoring (so that the second argument is an 7010 // expression, rather than a type), which should be done as part 7011 // of a larger effort to fix CheckPointerTypesForAssignment for 7012 // C++ semantics. 7013 if (getLangOptions().CPlusPlus && 7014 IsStringLiteralToNonConstPointerConversion(SrcExpr, DstType)) 7015 return false; 7016 DiagKind = diag::ext_typecheck_convert_discards_qualifiers; 7017 break; 7018 case IncompatibleNestedPointerQualifiers: 7019 DiagKind = diag::ext_nested_pointer_qualifier_mismatch; 7020 break; 7021 case IntToBlockPointer: 7022 DiagKind = diag::err_int_to_block_pointer; 7023 break; 7024 case IncompatibleBlockPointer: 7025 DiagKind = diag::err_typecheck_convert_incompatible_block_pointer; 7026 break; 7027 case IncompatibleObjCQualifiedId: 7028 // FIXME: Diagnose the problem in ObjCQualifiedIdTypesAreCompatible, since 7029 // it can give a more specific diagnostic. 7030 DiagKind = diag::warn_incompatible_qualified_id; 7031 break; 7032 case IncompatibleVectors: 7033 DiagKind = diag::warn_incompatible_vectors; 7034 break; 7035 case Incompatible: 7036 DiagKind = diag::err_typecheck_convert_incompatible; 7037 isInvalid = true; 7038 break; 7039 } 7040 7041 Diag(Loc, DiagKind) << DstType << SrcType << Action 7042 << SrcExpr->getSourceRange() << Hint; 7043 return isInvalid; 7044} 7045 7046bool Sema::VerifyIntegerConstantExpression(const Expr *E, llvm::APSInt *Result){ 7047 llvm::APSInt ICEResult; 7048 if (E->isIntegerConstantExpr(ICEResult, Context)) { 7049 if (Result) 7050 *Result = ICEResult; 7051 return false; 7052 } 7053 7054 Expr::EvalResult EvalResult; 7055 7056 if (!E->Evaluate(EvalResult, Context) || !EvalResult.Val.isInt() || 7057 EvalResult.HasSideEffects) { 7058 Diag(E->getExprLoc(), diag::err_expr_not_ice) << E->getSourceRange(); 7059 7060 if (EvalResult.Diag) { 7061 // We only show the note if it's not the usual "invalid subexpression" 7062 // or if it's actually in a subexpression. 7063 if (EvalResult.Diag != diag::note_invalid_subexpr_in_ice || 7064 E->IgnoreParens() != EvalResult.DiagExpr->IgnoreParens()) 7065 Diag(EvalResult.DiagLoc, EvalResult.Diag); 7066 } 7067 7068 return true; 7069 } 7070 7071 Diag(E->getExprLoc(), diag::ext_expr_not_ice) << 7072 E->getSourceRange(); 7073 7074 if (EvalResult.Diag && 7075 Diags.getDiagnosticLevel(diag::ext_expr_not_ice) != Diagnostic::Ignored) 7076 Diag(EvalResult.DiagLoc, EvalResult.Diag); 7077 7078 if (Result) 7079 *Result = EvalResult.Val.getInt(); 7080 return false; 7081} 7082 7083void 7084Sema::PushExpressionEvaluationContext(ExpressionEvaluationContext NewContext) { 7085 ExprEvalContexts.push_back( 7086 ExpressionEvaluationContextRecord(NewContext, ExprTemporaries.size())); 7087} 7088 7089void 7090Sema::PopExpressionEvaluationContext() { 7091 // Pop the current expression evaluation context off the stack. 7092 ExpressionEvaluationContextRecord Rec = ExprEvalContexts.back(); 7093 ExprEvalContexts.pop_back(); 7094 7095 if (Rec.Context == PotentiallyPotentiallyEvaluated) { 7096 if (Rec.PotentiallyReferenced) { 7097 // Mark any remaining declarations in the current position of the stack 7098 // as "referenced". If they were not meant to be referenced, semantic 7099 // analysis would have eliminated them (e.g., in ActOnCXXTypeId). 7100 for (PotentiallyReferencedDecls::iterator 7101 I = Rec.PotentiallyReferenced->begin(), 7102 IEnd = Rec.PotentiallyReferenced->end(); 7103 I != IEnd; ++I) 7104 MarkDeclarationReferenced(I->first, I->second); 7105 } 7106 7107 if (Rec.PotentiallyDiagnosed) { 7108 // Emit any pending diagnostics. 7109 for (PotentiallyEmittedDiagnostics::iterator 7110 I = Rec.PotentiallyDiagnosed->begin(), 7111 IEnd = Rec.PotentiallyDiagnosed->end(); 7112 I != IEnd; ++I) 7113 Diag(I->first, I->second); 7114 } 7115 } 7116 7117 // When are coming out of an unevaluated context, clear out any 7118 // temporaries that we may have created as part of the evaluation of 7119 // the expression in that context: they aren't relevant because they 7120 // will never be constructed. 7121 if (Rec.Context == Unevaluated && 7122 ExprTemporaries.size() > Rec.NumTemporaries) 7123 ExprTemporaries.erase(ExprTemporaries.begin() + Rec.NumTemporaries, 7124 ExprTemporaries.end()); 7125 7126 // Destroy the popped expression evaluation record. 7127 Rec.Destroy(); 7128} 7129 7130/// \brief Note that the given declaration was referenced in the source code. 7131/// 7132/// This routine should be invoke whenever a given declaration is referenced 7133/// in the source code, and where that reference occurred. If this declaration 7134/// reference means that the the declaration is used (C++ [basic.def.odr]p2, 7135/// C99 6.9p3), then the declaration will be marked as used. 7136/// 7137/// \param Loc the location where the declaration was referenced. 7138/// 7139/// \param D the declaration that has been referenced by the source code. 7140void Sema::MarkDeclarationReferenced(SourceLocation Loc, Decl *D) { 7141 assert(D && "No declaration?"); 7142 7143 if (D->isUsed()) 7144 return; 7145 7146 // Mark a parameter or variable declaration "used", regardless of whether we're in a 7147 // template or not. The reason for this is that unevaluated expressions 7148 // (e.g. (void)sizeof()) constitute a use for warning purposes (-Wunused-variables and 7149 // -Wunused-parameters) 7150 if (isa<ParmVarDecl>(D) || 7151 (isa<VarDecl>(D) && D->getDeclContext()->isFunctionOrMethod())) 7152 D->setUsed(true); 7153 7154 // Do not mark anything as "used" within a dependent context; wait for 7155 // an instantiation. 7156 if (CurContext->isDependentContext()) 7157 return; 7158 7159 switch (ExprEvalContexts.back().Context) { 7160 case Unevaluated: 7161 // We are in an expression that is not potentially evaluated; do nothing. 7162 return; 7163 7164 case PotentiallyEvaluated: 7165 // We are in a potentially-evaluated expression, so this declaration is 7166 // "used"; handle this below. 7167 break; 7168 7169 case PotentiallyPotentiallyEvaluated: 7170 // We are in an expression that may be potentially evaluated; queue this 7171 // declaration reference until we know whether the expression is 7172 // potentially evaluated. 7173 ExprEvalContexts.back().addReferencedDecl(Loc, D); 7174 return; 7175 } 7176 7177 // Note that this declaration has been used. 7178 if (CXXConstructorDecl *Constructor = dyn_cast<CXXConstructorDecl>(D)) { 7179 unsigned TypeQuals; 7180 if (Constructor->isImplicit() && Constructor->isDefaultConstructor()) { 7181 if (!Constructor->isUsed()) 7182 DefineImplicitDefaultConstructor(Loc, Constructor); 7183 } else if (Constructor->isImplicit() && 7184 Constructor->isCopyConstructor(TypeQuals)) { 7185 if (!Constructor->isUsed()) 7186 DefineImplicitCopyConstructor(Loc, Constructor, TypeQuals); 7187 } 7188 7189 MaybeMarkVirtualMembersReferenced(Loc, Constructor); 7190 } else if (CXXDestructorDecl *Destructor = dyn_cast<CXXDestructorDecl>(D)) { 7191 if (Destructor->isImplicit() && !Destructor->isUsed()) 7192 DefineImplicitDestructor(Loc, Destructor); 7193 7194 } else if (CXXMethodDecl *MethodDecl = dyn_cast<CXXMethodDecl>(D)) { 7195 if (MethodDecl->isImplicit() && MethodDecl->isOverloadedOperator() && 7196 MethodDecl->getOverloadedOperator() == OO_Equal) { 7197 if (!MethodDecl->isUsed()) 7198 DefineImplicitOverloadedAssign(Loc, MethodDecl); 7199 } 7200 } 7201 if (FunctionDecl *Function = dyn_cast<FunctionDecl>(D)) { 7202 // Implicit instantiation of function templates and member functions of 7203 // class templates. 7204 if (!Function->getBody() && Function->isImplicitlyInstantiable()) { 7205 bool AlreadyInstantiated = false; 7206 if (FunctionTemplateSpecializationInfo *SpecInfo 7207 = Function->getTemplateSpecializationInfo()) { 7208 if (SpecInfo->getPointOfInstantiation().isInvalid()) 7209 SpecInfo->setPointOfInstantiation(Loc); 7210 else if (SpecInfo->getTemplateSpecializationKind() 7211 == TSK_ImplicitInstantiation) 7212 AlreadyInstantiated = true; 7213 } else if (MemberSpecializationInfo *MSInfo 7214 = Function->getMemberSpecializationInfo()) { 7215 if (MSInfo->getPointOfInstantiation().isInvalid()) 7216 MSInfo->setPointOfInstantiation(Loc); 7217 else if (MSInfo->getTemplateSpecializationKind() 7218 == TSK_ImplicitInstantiation) 7219 AlreadyInstantiated = true; 7220 } 7221 7222 if (!AlreadyInstantiated) { 7223 if (isa<CXXRecordDecl>(Function->getDeclContext()) && 7224 cast<CXXRecordDecl>(Function->getDeclContext())->isLocalClass()) 7225 PendingLocalImplicitInstantiations.push_back(std::make_pair(Function, 7226 Loc)); 7227 else 7228 PendingImplicitInstantiations.push_back(std::make_pair(Function, 7229 Loc)); 7230 } 7231 } 7232 7233 // FIXME: keep track of references to static functions 7234 Function->setUsed(true); 7235 return; 7236 } 7237 7238 if (VarDecl *Var = dyn_cast<VarDecl>(D)) { 7239 // Implicit instantiation of static data members of class templates. 7240 if (Var->isStaticDataMember() && 7241 Var->getInstantiatedFromStaticDataMember()) { 7242 MemberSpecializationInfo *MSInfo = Var->getMemberSpecializationInfo(); 7243 assert(MSInfo && "Missing member specialization information?"); 7244 if (MSInfo->getPointOfInstantiation().isInvalid() && 7245 MSInfo->getTemplateSpecializationKind()== TSK_ImplicitInstantiation) { 7246 MSInfo->setPointOfInstantiation(Loc); 7247 PendingImplicitInstantiations.push_back(std::make_pair(Var, Loc)); 7248 } 7249 } 7250 7251 // FIXME: keep track of references to static data? 7252 7253 D->setUsed(true); 7254 return; 7255 } 7256} 7257 7258/// \brief Emit a diagnostic that describes an effect on the run-time behavior 7259/// of the program being compiled. 7260/// 7261/// This routine emits the given diagnostic when the code currently being 7262/// type-checked is "potentially evaluated", meaning that there is a 7263/// possibility that the code will actually be executable. Code in sizeof() 7264/// expressions, code used only during overload resolution, etc., are not 7265/// potentially evaluated. This routine will suppress such diagnostics or, 7266/// in the absolutely nutty case of potentially potentially evaluated 7267/// expressions (C++ typeid), queue the diagnostic to potentially emit it 7268/// later. 7269/// 7270/// This routine should be used for all diagnostics that describe the run-time 7271/// behavior of a program, such as passing a non-POD value through an ellipsis. 7272/// Failure to do so will likely result in spurious diagnostics or failures 7273/// during overload resolution or within sizeof/alignof/typeof/typeid. 7274bool Sema::DiagRuntimeBehavior(SourceLocation Loc, 7275 const PartialDiagnostic &PD) { 7276 switch (ExprEvalContexts.back().Context ) { 7277 case Unevaluated: 7278 // The argument will never be evaluated, so don't complain. 7279 break; 7280 7281 case PotentiallyEvaluated: 7282 Diag(Loc, PD); 7283 return true; 7284 7285 case PotentiallyPotentiallyEvaluated: 7286 ExprEvalContexts.back().addDiagnostic(Loc, PD); 7287 break; 7288 } 7289 7290 return false; 7291} 7292 7293bool Sema::CheckCallReturnType(QualType ReturnType, SourceLocation Loc, 7294 CallExpr *CE, FunctionDecl *FD) { 7295 if (ReturnType->isVoidType() || !ReturnType->isIncompleteType()) 7296 return false; 7297 7298 PartialDiagnostic Note = 7299 FD ? PDiag(diag::note_function_with_incomplete_return_type_declared_here) 7300 << FD->getDeclName() : PDiag(); 7301 SourceLocation NoteLoc = FD ? FD->getLocation() : SourceLocation(); 7302 7303 if (RequireCompleteType(Loc, ReturnType, 7304 FD ? 7305 PDiag(diag::err_call_function_incomplete_return) 7306 << CE->getSourceRange() << FD->getDeclName() : 7307 PDiag(diag::err_call_incomplete_return) 7308 << CE->getSourceRange(), 7309 std::make_pair(NoteLoc, Note))) 7310 return true; 7311 7312 return false; 7313} 7314 7315// Diagnose the common s/=/==/ typo. Note that adding parentheses 7316// will prevent this condition from triggering, which is what we want. 7317void Sema::DiagnoseAssignmentAsCondition(Expr *E) { 7318 SourceLocation Loc; 7319 7320 unsigned diagnostic = diag::warn_condition_is_assignment; 7321 7322 if (isa<BinaryOperator>(E)) { 7323 BinaryOperator *Op = cast<BinaryOperator>(E); 7324 if (Op->getOpcode() != BinaryOperator::Assign) 7325 return; 7326 7327 // Greylist some idioms by putting them into a warning subcategory. 7328 if (ObjCMessageExpr *ME 7329 = dyn_cast<ObjCMessageExpr>(Op->getRHS()->IgnoreParenCasts())) { 7330 Selector Sel = ME->getSelector(); 7331 7332 // self = [<foo> init...] 7333 if (isSelfExpr(Op->getLHS()) 7334 && Sel.getIdentifierInfoForSlot(0)->getName().startswith("init")) 7335 diagnostic = diag::warn_condition_is_idiomatic_assignment; 7336 7337 // <foo> = [<bar> nextObject] 7338 else if (Sel.isUnarySelector() && 7339 Sel.getIdentifierInfoForSlot(0)->getName() == "nextObject") 7340 diagnostic = diag::warn_condition_is_idiomatic_assignment; 7341 } 7342 7343 Loc = Op->getOperatorLoc(); 7344 } else if (isa<CXXOperatorCallExpr>(E)) { 7345 CXXOperatorCallExpr *Op = cast<CXXOperatorCallExpr>(E); 7346 if (Op->getOperator() != OO_Equal) 7347 return; 7348 7349 Loc = Op->getOperatorLoc(); 7350 } else { 7351 // Not an assignment. 7352 return; 7353 } 7354 7355 SourceLocation Open = E->getSourceRange().getBegin(); 7356 SourceLocation Close = PP.getLocForEndOfToken(E->getSourceRange().getEnd()); 7357 7358 Diag(Loc, diagnostic) 7359 << E->getSourceRange() 7360 << CodeModificationHint::CreateInsertion(Open, "(") 7361 << CodeModificationHint::CreateInsertion(Close, ")"); 7362 Diag(Loc, diag::note_condition_assign_to_comparison) 7363 << CodeModificationHint::CreateReplacement(Loc, "=="); 7364} 7365 7366bool Sema::CheckBooleanCondition(Expr *&E, SourceLocation Loc) { 7367 DiagnoseAssignmentAsCondition(E); 7368 7369 if (!E->isTypeDependent()) { 7370 DefaultFunctionArrayConversion(E); 7371 7372 QualType T = E->getType(); 7373 7374 if (getLangOptions().CPlusPlus) { 7375 if (CheckCXXBooleanCondition(E)) // C++ 6.4p4 7376 return true; 7377 } else if (!T->isScalarType()) { // C99 6.8.4.1p1 7378 Diag(Loc, diag::err_typecheck_statement_requires_scalar) 7379 << T << E->getSourceRange(); 7380 return true; 7381 } 7382 } 7383 7384 return false; 7385} 7386