SemaExpr.cpp revision 6d53ea6153217b57da6690128eb80bf3c7233f46
1//===--- SemaExpr.cpp - Semantic Analysis for Expressions -----------------===// 2// 3// The LLVM Compiler Infrastructure 4// 5// This file is distributed under the University of Illinois Open Source 6// License. See LICENSE.TXT for details. 7// 8//===----------------------------------------------------------------------===// 9// 10// This file implements semantic analysis for expressions. 11// 12//===----------------------------------------------------------------------===// 13 14#include "Sema.h" 15#include "Lookup.h" 16#include "clang/AST/ASTContext.h" 17#include "clang/AST/DeclObjC.h" 18#include "clang/AST/DeclTemplate.h" 19#include "clang/AST/ExprCXX.h" 20#include "clang/AST/ExprObjC.h" 21#include "clang/Basic/PartialDiagnostic.h" 22#include "clang/Basic/SourceManager.h" 23#include "clang/Basic/TargetInfo.h" 24#include "clang/Lex/LiteralSupport.h" 25#include "clang/Lex/Preprocessor.h" 26#include "clang/Parse/DeclSpec.h" 27#include "clang/Parse/Designator.h" 28#include "clang/Parse/Scope.h" 29#include "clang/Parse/Template.h" 30using namespace clang; 31 32 33/// \brief Determine whether the use of this declaration is valid, and 34/// emit any corresponding diagnostics. 35/// 36/// This routine diagnoses various problems with referencing 37/// declarations that can occur when using a declaration. For example, 38/// it might warn if a deprecated or unavailable declaration is being 39/// used, or produce an error (and return true) if a C++0x deleted 40/// function is being used. 41/// 42/// If IgnoreDeprecated is set to true, this should not want about deprecated 43/// decls. 44/// 45/// \returns true if there was an error (this declaration cannot be 46/// referenced), false otherwise. 47/// 48bool Sema::DiagnoseUseOfDecl(NamedDecl *D, SourceLocation Loc) { 49 // See if the decl is deprecated. 50 if (D->getAttr<DeprecatedAttr>()) { 51 EmitDeprecationWarning(D, Loc); 52 } 53 54 // See if the decl is unavailable 55 if (D->getAttr<UnavailableAttr>()) { 56 Diag(Loc, diag::warn_unavailable) << D->getDeclName(); 57 Diag(D->getLocation(), diag::note_unavailable_here) << 0; 58 } 59 60 // See if this is a deleted function. 61 if (FunctionDecl *FD = dyn_cast<FunctionDecl>(D)) { 62 if (FD->isDeleted()) { 63 Diag(Loc, diag::err_deleted_function_use); 64 Diag(D->getLocation(), diag::note_unavailable_here) << true; 65 return true; 66 } 67 } 68 69 return false; 70} 71 72/// DiagnoseSentinelCalls - This routine checks on method dispatch calls 73/// (and other functions in future), which have been declared with sentinel 74/// attribute. It warns if call does not have the sentinel argument. 75/// 76void Sema::DiagnoseSentinelCalls(NamedDecl *D, SourceLocation Loc, 77 Expr **Args, unsigned NumArgs) { 78 const SentinelAttr *attr = D->getAttr<SentinelAttr>(); 79 if (!attr) 80 return; 81 int sentinelPos = attr->getSentinel(); 82 int nullPos = attr->getNullPos(); 83 84 // FIXME. ObjCMethodDecl and FunctionDecl need be derived from the same common 85 // base class. Then we won't be needing two versions of the same code. 86 unsigned int i = 0; 87 bool warnNotEnoughArgs = false; 88 int isMethod = 0; 89 if (ObjCMethodDecl *MD = dyn_cast<ObjCMethodDecl>(D)) { 90 // skip over named parameters. 91 ObjCMethodDecl::param_iterator P, E = MD->param_end(); 92 for (P = MD->param_begin(); (P != E && i < NumArgs); ++P) { 93 if (nullPos) 94 --nullPos; 95 else 96 ++i; 97 } 98 warnNotEnoughArgs = (P != E || i >= NumArgs); 99 isMethod = 1; 100 } else if (FunctionDecl *FD = dyn_cast<FunctionDecl>(D)) { 101 // skip over named parameters. 102 ObjCMethodDecl::param_iterator P, E = FD->param_end(); 103 for (P = FD->param_begin(); (P != E && i < NumArgs); ++P) { 104 if (nullPos) 105 --nullPos; 106 else 107 ++i; 108 } 109 warnNotEnoughArgs = (P != E || i >= NumArgs); 110 } else if (VarDecl *V = dyn_cast<VarDecl>(D)) { 111 // block or function pointer call. 112 QualType Ty = V->getType(); 113 if (Ty->isBlockPointerType() || Ty->isFunctionPointerType()) { 114 const FunctionType *FT = Ty->isFunctionPointerType() 115 ? Ty->getAs<PointerType>()->getPointeeType()->getAs<FunctionType>() 116 : Ty->getAs<BlockPointerType>()->getPointeeType()->getAs<FunctionType>(); 117 if (const FunctionProtoType *Proto = dyn_cast<FunctionProtoType>(FT)) { 118 unsigned NumArgsInProto = Proto->getNumArgs(); 119 unsigned k; 120 for (k = 0; (k != NumArgsInProto && i < NumArgs); k++) { 121 if (nullPos) 122 --nullPos; 123 else 124 ++i; 125 } 126 warnNotEnoughArgs = (k != NumArgsInProto || i >= NumArgs); 127 } 128 if (Ty->isBlockPointerType()) 129 isMethod = 2; 130 } else 131 return; 132 } else 133 return; 134 135 if (warnNotEnoughArgs) { 136 Diag(Loc, diag::warn_not_enough_argument) << D->getDeclName(); 137 Diag(D->getLocation(), diag::note_sentinel_here) << isMethod; 138 return; 139 } 140 int sentinel = i; 141 while (sentinelPos > 0 && i < NumArgs-1) { 142 --sentinelPos; 143 ++i; 144 } 145 if (sentinelPos > 0) { 146 Diag(Loc, diag::warn_not_enough_argument) << D->getDeclName(); 147 Diag(D->getLocation(), diag::note_sentinel_here) << isMethod; 148 return; 149 } 150 while (i < NumArgs-1) { 151 ++i; 152 ++sentinel; 153 } 154 Expr *sentinelExpr = Args[sentinel]; 155 if (sentinelExpr && (!isa<GNUNullExpr>(sentinelExpr) && 156 (!sentinelExpr->getType()->isPointerType() || 157 !sentinelExpr->isNullPointerConstant(Context, 158 Expr::NPC_ValueDependentIsNull)))) { 159 Diag(Loc, diag::warn_missing_sentinel) << isMethod; 160 Diag(D->getLocation(), diag::note_sentinel_here) << isMethod; 161 } 162 return; 163} 164 165SourceRange Sema::getExprRange(ExprTy *E) const { 166 Expr *Ex = (Expr *)E; 167 return Ex? Ex->getSourceRange() : SourceRange(); 168} 169 170//===----------------------------------------------------------------------===// 171// Standard Promotions and Conversions 172//===----------------------------------------------------------------------===// 173 174/// DefaultFunctionArrayConversion (C99 6.3.2.1p3, C99 6.3.2.1p4). 175void Sema::DefaultFunctionArrayConversion(Expr *&E) { 176 QualType Ty = E->getType(); 177 assert(!Ty.isNull() && "DefaultFunctionArrayConversion - missing type"); 178 179 if (Ty->isFunctionType()) 180 ImpCastExprToType(E, Context.getPointerType(Ty), 181 CastExpr::CK_FunctionToPointerDecay); 182 else if (Ty->isArrayType()) { 183 // In C90 mode, arrays only promote to pointers if the array expression is 184 // an lvalue. The relevant legalese is C90 6.2.2.1p3: "an lvalue that has 185 // type 'array of type' is converted to an expression that has type 'pointer 186 // to type'...". In C99 this was changed to: C99 6.3.2.1p3: "an expression 187 // that has type 'array of type' ...". The relevant change is "an lvalue" 188 // (C90) to "an expression" (C99). 189 // 190 // C++ 4.2p1: 191 // An lvalue or rvalue of type "array of N T" or "array of unknown bound of 192 // T" can be converted to an rvalue of type "pointer to T". 193 // 194 if (getLangOptions().C99 || getLangOptions().CPlusPlus || 195 E->isLvalue(Context) == Expr::LV_Valid) 196 ImpCastExprToType(E, Context.getArrayDecayedType(Ty), 197 CastExpr::CK_ArrayToPointerDecay); 198 } 199} 200 201/// UsualUnaryConversions - Performs various conversions that are common to most 202/// operators (C99 6.3). The conversions of array and function types are 203/// sometimes surpressed. For example, the array->pointer conversion doesn't 204/// apply if the array is an argument to the sizeof or address (&) operators. 205/// In these instances, this routine should *not* be called. 206Expr *Sema::UsualUnaryConversions(Expr *&Expr) { 207 QualType Ty = Expr->getType(); 208 assert(!Ty.isNull() && "UsualUnaryConversions - missing type"); 209 210 // C99 6.3.1.1p2: 211 // 212 // The following may be used in an expression wherever an int or 213 // unsigned int may be used: 214 // - an object or expression with an integer type whose integer 215 // conversion rank is less than or equal to the rank of int 216 // and unsigned int. 217 // - A bit-field of type _Bool, int, signed int, or unsigned int. 218 // 219 // If an int can represent all values of the original type, the 220 // value is converted to an int; otherwise, it is converted to an 221 // unsigned int. These are called the integer promotions. All 222 // other types are unchanged by the integer promotions. 223 QualType PTy = Context.isPromotableBitField(Expr); 224 if (!PTy.isNull()) { 225 ImpCastExprToType(Expr, PTy, CastExpr::CK_IntegralCast); 226 return Expr; 227 } 228 if (Ty->isPromotableIntegerType()) { 229 QualType PT = Context.getPromotedIntegerType(Ty); 230 ImpCastExprToType(Expr, PT, CastExpr::CK_IntegralCast); 231 return Expr; 232 } 233 234 DefaultFunctionArrayConversion(Expr); 235 return Expr; 236} 237 238/// DefaultArgumentPromotion (C99 6.5.2.2p6). Used for function calls that 239/// do not have a prototype. Arguments that have type float are promoted to 240/// double. All other argument types are converted by UsualUnaryConversions(). 241void Sema::DefaultArgumentPromotion(Expr *&Expr) { 242 QualType Ty = Expr->getType(); 243 assert(!Ty.isNull() && "DefaultArgumentPromotion - missing type"); 244 245 // If this is a 'float' (CVR qualified or typedef) promote to double. 246 if (const BuiltinType *BT = Ty->getAs<BuiltinType>()) 247 if (BT->getKind() == BuiltinType::Float) 248 return ImpCastExprToType(Expr, Context.DoubleTy, 249 CastExpr::CK_FloatingCast); 250 251 UsualUnaryConversions(Expr); 252} 253 254/// DefaultVariadicArgumentPromotion - Like DefaultArgumentPromotion, but 255/// will warn if the resulting type is not a POD type, and rejects ObjC 256/// interfaces passed by value. This returns true if the argument type is 257/// completely illegal. 258bool Sema::DefaultVariadicArgumentPromotion(Expr *&Expr, VariadicCallType CT) { 259 DefaultArgumentPromotion(Expr); 260 261 if (Expr->getType()->isObjCInterfaceType()) { 262 Diag(Expr->getLocStart(), 263 diag::err_cannot_pass_objc_interface_to_vararg) 264 << Expr->getType() << CT; 265 return true; 266 } 267 268 if (!Expr->getType()->isPODType()) 269 Diag(Expr->getLocStart(), diag::warn_cannot_pass_non_pod_arg_to_vararg) 270 << Expr->getType() << CT; 271 272 return false; 273} 274 275 276/// UsualArithmeticConversions - Performs various conversions that are common to 277/// binary operators (C99 6.3.1.8). If both operands aren't arithmetic, this 278/// routine returns the first non-arithmetic type found. The client is 279/// responsible for emitting appropriate error diagnostics. 280/// FIXME: verify the conversion rules for "complex int" are consistent with 281/// GCC. 282QualType Sema::UsualArithmeticConversions(Expr *&lhsExpr, Expr *&rhsExpr, 283 bool isCompAssign) { 284 if (!isCompAssign) 285 UsualUnaryConversions(lhsExpr); 286 287 UsualUnaryConversions(rhsExpr); 288 289 // For conversion purposes, we ignore any qualifiers. 290 // For example, "const float" and "float" are equivalent. 291 QualType lhs = 292 Context.getCanonicalType(lhsExpr->getType()).getUnqualifiedType(); 293 QualType rhs = 294 Context.getCanonicalType(rhsExpr->getType()).getUnqualifiedType(); 295 296 // If both types are identical, no conversion is needed. 297 if (lhs == rhs) 298 return lhs; 299 300 // If either side is a non-arithmetic type (e.g. a pointer), we are done. 301 // The caller can deal with this (e.g. pointer + int). 302 if (!lhs->isArithmeticType() || !rhs->isArithmeticType()) 303 return lhs; 304 305 // Perform bitfield promotions. 306 QualType LHSBitfieldPromoteTy = Context.isPromotableBitField(lhsExpr); 307 if (!LHSBitfieldPromoteTy.isNull()) 308 lhs = LHSBitfieldPromoteTy; 309 QualType RHSBitfieldPromoteTy = Context.isPromotableBitField(rhsExpr); 310 if (!RHSBitfieldPromoteTy.isNull()) 311 rhs = RHSBitfieldPromoteTy; 312 313 QualType destType = Context.UsualArithmeticConversionsType(lhs, rhs); 314 if (!isCompAssign) 315 ImpCastExprToType(lhsExpr, destType, CastExpr::CK_Unknown); 316 ImpCastExprToType(rhsExpr, destType, CastExpr::CK_Unknown); 317 return destType; 318} 319 320//===----------------------------------------------------------------------===// 321// Semantic Analysis for various Expression Types 322//===----------------------------------------------------------------------===// 323 324 325/// ActOnStringLiteral - The specified tokens were lexed as pasted string 326/// fragments (e.g. "foo" "bar" L"baz"). The result string has to handle string 327/// concatenation ([C99 5.1.1.2, translation phase #6]), so it may come from 328/// multiple tokens. However, the common case is that StringToks points to one 329/// string. 330/// 331Action::OwningExprResult 332Sema::ActOnStringLiteral(const Token *StringToks, unsigned NumStringToks) { 333 assert(NumStringToks && "Must have at least one string!"); 334 335 StringLiteralParser Literal(StringToks, NumStringToks, PP); 336 if (Literal.hadError) 337 return ExprError(); 338 339 llvm::SmallVector<SourceLocation, 4> StringTokLocs; 340 for (unsigned i = 0; i != NumStringToks; ++i) 341 StringTokLocs.push_back(StringToks[i].getLocation()); 342 343 QualType StrTy = Context.CharTy; 344 if (Literal.AnyWide) StrTy = Context.getWCharType(); 345 if (Literal.Pascal) StrTy = Context.UnsignedCharTy; 346 347 // A C++ string literal has a const-qualified element type (C++ 2.13.4p1). 348 if (getLangOptions().CPlusPlus) 349 StrTy.addConst(); 350 351 // Get an array type for the string, according to C99 6.4.5. This includes 352 // the nul terminator character as well as the string length for pascal 353 // strings. 354 StrTy = Context.getConstantArrayType(StrTy, 355 llvm::APInt(32, Literal.GetNumStringChars()+1), 356 ArrayType::Normal, 0); 357 358 // Pass &StringTokLocs[0], StringTokLocs.size() to factory! 359 return Owned(StringLiteral::Create(Context, Literal.GetString(), 360 Literal.GetStringLength(), 361 Literal.AnyWide, StrTy, 362 &StringTokLocs[0], 363 StringTokLocs.size())); 364} 365 366/// ShouldSnapshotBlockValueReference - Return true if a reference inside of 367/// CurBlock to VD should cause it to be snapshotted (as we do for auto 368/// variables defined outside the block) or false if this is not needed (e.g. 369/// for values inside the block or for globals). 370/// 371/// This also keeps the 'hasBlockDeclRefExprs' in the BlockSemaInfo records 372/// up-to-date. 373/// 374static bool ShouldSnapshotBlockValueReference(BlockSemaInfo *CurBlock, 375 ValueDecl *VD) { 376 // If the value is defined inside the block, we couldn't snapshot it even if 377 // we wanted to. 378 if (CurBlock->TheDecl == VD->getDeclContext()) 379 return false; 380 381 // If this is an enum constant or function, it is constant, don't snapshot. 382 if (isa<EnumConstantDecl>(VD) || isa<FunctionDecl>(VD)) 383 return false; 384 385 // If this is a reference to an extern, static, or global variable, no need to 386 // snapshot it. 387 // FIXME: What about 'const' variables in C++? 388 if (const VarDecl *Var = dyn_cast<VarDecl>(VD)) 389 if (!Var->hasLocalStorage()) 390 return false; 391 392 // Blocks that have these can't be constant. 393 CurBlock->hasBlockDeclRefExprs = true; 394 395 // If we have nested blocks, the decl may be declared in an outer block (in 396 // which case that outer block doesn't get "hasBlockDeclRefExprs") or it may 397 // be defined outside all of the current blocks (in which case the blocks do 398 // all get the bit). Walk the nesting chain. 399 for (BlockSemaInfo *NextBlock = CurBlock->PrevBlockInfo; NextBlock; 400 NextBlock = NextBlock->PrevBlockInfo) { 401 // If we found the defining block for the variable, don't mark the block as 402 // having a reference outside it. 403 if (NextBlock->TheDecl == VD->getDeclContext()) 404 break; 405 406 // Otherwise, the DeclRef from the inner block causes the outer one to need 407 // a snapshot as well. 408 NextBlock->hasBlockDeclRefExprs = true; 409 } 410 411 return true; 412} 413 414 415 416/// BuildDeclRefExpr - Build a DeclRefExpr. 417Sema::OwningExprResult 418Sema::BuildDeclRefExpr(NamedDecl *D, QualType Ty, SourceLocation Loc, 419 const CXXScopeSpec *SS) { 420 if (Context.getCanonicalType(Ty) == Context.UndeducedAutoTy) { 421 Diag(Loc, 422 diag::err_auto_variable_cannot_appear_in_own_initializer) 423 << D->getDeclName(); 424 return ExprError(); 425 } 426 427 if (const VarDecl *VD = dyn_cast<VarDecl>(D)) { 428 if (const CXXMethodDecl *MD = dyn_cast<CXXMethodDecl>(CurContext)) { 429 if (const FunctionDecl *FD = MD->getParent()->isLocalClass()) { 430 if (VD->hasLocalStorage() && VD->getDeclContext() != CurContext) { 431 Diag(Loc, diag::err_reference_to_local_var_in_enclosing_function) 432 << D->getIdentifier() << FD->getDeclName(); 433 Diag(D->getLocation(), diag::note_local_variable_declared_here) 434 << D->getIdentifier(); 435 return ExprError(); 436 } 437 } 438 } 439 } 440 441 MarkDeclarationReferenced(Loc, D); 442 443 return Owned(DeclRefExpr::Create(Context, 444 SS? (NestedNameSpecifier *)SS->getScopeRep() : 0, 445 SS? SS->getRange() : SourceRange(), 446 D, Loc, Ty)); 447} 448 449/// getObjectForAnonymousRecordDecl - Retrieve the (unnamed) field or 450/// variable corresponding to the anonymous union or struct whose type 451/// is Record. 452static Decl *getObjectForAnonymousRecordDecl(ASTContext &Context, 453 RecordDecl *Record) { 454 assert(Record->isAnonymousStructOrUnion() && 455 "Record must be an anonymous struct or union!"); 456 457 // FIXME: Once Decls are directly linked together, this will be an O(1) 458 // operation rather than a slow walk through DeclContext's vector (which 459 // itself will be eliminated). DeclGroups might make this even better. 460 DeclContext *Ctx = Record->getDeclContext(); 461 for (DeclContext::decl_iterator D = Ctx->decls_begin(), 462 DEnd = Ctx->decls_end(); 463 D != DEnd; ++D) { 464 if (*D == Record) { 465 // The object for the anonymous struct/union directly 466 // follows its type in the list of declarations. 467 ++D; 468 assert(D != DEnd && "Missing object for anonymous record"); 469 assert(!cast<NamedDecl>(*D)->getDeclName() && "Decl should be unnamed"); 470 return *D; 471 } 472 } 473 474 assert(false && "Missing object for anonymous record"); 475 return 0; 476} 477 478/// \brief Given a field that represents a member of an anonymous 479/// struct/union, build the path from that field's context to the 480/// actual member. 481/// 482/// Construct the sequence of field member references we'll have to 483/// perform to get to the field in the anonymous union/struct. The 484/// list of members is built from the field outward, so traverse it 485/// backwards to go from an object in the current context to the field 486/// we found. 487/// 488/// \returns The variable from which the field access should begin, 489/// for an anonymous struct/union that is not a member of another 490/// class. Otherwise, returns NULL. 491VarDecl *Sema::BuildAnonymousStructUnionMemberPath(FieldDecl *Field, 492 llvm::SmallVectorImpl<FieldDecl *> &Path) { 493 assert(Field->getDeclContext()->isRecord() && 494 cast<RecordDecl>(Field->getDeclContext())->isAnonymousStructOrUnion() 495 && "Field must be stored inside an anonymous struct or union"); 496 497 Path.push_back(Field); 498 VarDecl *BaseObject = 0; 499 DeclContext *Ctx = Field->getDeclContext(); 500 do { 501 RecordDecl *Record = cast<RecordDecl>(Ctx); 502 Decl *AnonObject = getObjectForAnonymousRecordDecl(Context, Record); 503 if (FieldDecl *AnonField = dyn_cast<FieldDecl>(AnonObject)) 504 Path.push_back(AnonField); 505 else { 506 BaseObject = cast<VarDecl>(AnonObject); 507 break; 508 } 509 Ctx = Ctx->getParent(); 510 } while (Ctx->isRecord() && 511 cast<RecordDecl>(Ctx)->isAnonymousStructOrUnion()); 512 513 return BaseObject; 514} 515 516Sema::OwningExprResult 517Sema::BuildAnonymousStructUnionMemberReference(SourceLocation Loc, 518 FieldDecl *Field, 519 Expr *BaseObjectExpr, 520 SourceLocation OpLoc) { 521 llvm::SmallVector<FieldDecl *, 4> AnonFields; 522 VarDecl *BaseObject = BuildAnonymousStructUnionMemberPath(Field, 523 AnonFields); 524 525 // Build the expression that refers to the base object, from 526 // which we will build a sequence of member references to each 527 // of the anonymous union objects and, eventually, the field we 528 // found via name lookup. 529 bool BaseObjectIsPointer = false; 530 Qualifiers BaseQuals; 531 if (BaseObject) { 532 // BaseObject is an anonymous struct/union variable (and is, 533 // therefore, not part of another non-anonymous record). 534 if (BaseObjectExpr) BaseObjectExpr->Destroy(Context); 535 MarkDeclarationReferenced(Loc, BaseObject); 536 BaseObjectExpr = new (Context) DeclRefExpr(BaseObject,BaseObject->getType(), 537 SourceLocation()); 538 BaseQuals 539 = Context.getCanonicalType(BaseObject->getType()).getQualifiers(); 540 } else if (BaseObjectExpr) { 541 // The caller provided the base object expression. Determine 542 // whether its a pointer and whether it adds any qualifiers to the 543 // anonymous struct/union fields we're looking into. 544 QualType ObjectType = BaseObjectExpr->getType(); 545 if (const PointerType *ObjectPtr = ObjectType->getAs<PointerType>()) { 546 BaseObjectIsPointer = true; 547 ObjectType = ObjectPtr->getPointeeType(); 548 } 549 BaseQuals 550 = Context.getCanonicalType(ObjectType).getQualifiers(); 551 } else { 552 // We've found a member of an anonymous struct/union that is 553 // inside a non-anonymous struct/union, so in a well-formed 554 // program our base object expression is "this". 555 if (CXXMethodDecl *MD = dyn_cast<CXXMethodDecl>(CurContext)) { 556 if (!MD->isStatic()) { 557 QualType AnonFieldType 558 = Context.getTagDeclType( 559 cast<RecordDecl>(AnonFields.back()->getDeclContext())); 560 QualType ThisType = Context.getTagDeclType(MD->getParent()); 561 if ((Context.getCanonicalType(AnonFieldType) 562 == Context.getCanonicalType(ThisType)) || 563 IsDerivedFrom(ThisType, AnonFieldType)) { 564 // Our base object expression is "this". 565 BaseObjectExpr = new (Context) CXXThisExpr(SourceLocation(), 566 MD->getThisType(Context)); 567 BaseObjectIsPointer = true; 568 } 569 } else { 570 return ExprError(Diag(Loc,diag::err_invalid_member_use_in_static_method) 571 << Field->getDeclName()); 572 } 573 BaseQuals = Qualifiers::fromCVRMask(MD->getTypeQualifiers()); 574 } 575 576 if (!BaseObjectExpr) 577 return ExprError(Diag(Loc, diag::err_invalid_non_static_member_use) 578 << Field->getDeclName()); 579 } 580 581 // Build the implicit member references to the field of the 582 // anonymous struct/union. 583 Expr *Result = BaseObjectExpr; 584 Qualifiers ResultQuals = BaseQuals; 585 for (llvm::SmallVector<FieldDecl *, 4>::reverse_iterator 586 FI = AnonFields.rbegin(), FIEnd = AnonFields.rend(); 587 FI != FIEnd; ++FI) { 588 QualType MemberType = (*FI)->getType(); 589 Qualifiers MemberTypeQuals = 590 Context.getCanonicalType(MemberType).getQualifiers(); 591 592 // CVR attributes from the base are picked up by members, 593 // except that 'mutable' members don't pick up 'const'. 594 if ((*FI)->isMutable()) 595 ResultQuals.removeConst(); 596 597 // GC attributes are never picked up by members. 598 ResultQuals.removeObjCGCAttr(); 599 600 // TR 18037 does not allow fields to be declared with address spaces. 601 assert(!MemberTypeQuals.hasAddressSpace()); 602 603 Qualifiers NewQuals = ResultQuals + MemberTypeQuals; 604 if (NewQuals != MemberTypeQuals) 605 MemberType = Context.getQualifiedType(MemberType, NewQuals); 606 607 MarkDeclarationReferenced(Loc, *FI); 608 // FIXME: Might this end up being a qualified name? 609 Result = new (Context) MemberExpr(Result, BaseObjectIsPointer, *FI, 610 OpLoc, MemberType); 611 BaseObjectIsPointer = false; 612 ResultQuals = NewQuals; 613 } 614 615 return Owned(Result); 616} 617 618/// Decomposes the given name into a DeclarationName, its location, and 619/// possibly a list of template arguments. 620/// 621/// If this produces template arguments, it is permitted to call 622/// DecomposeTemplateName. 623/// 624/// This actually loses a lot of source location information for 625/// non-standard name kinds; we should consider preserving that in 626/// some way. 627static void DecomposeUnqualifiedId(Sema &SemaRef, 628 const UnqualifiedId &Id, 629 TemplateArgumentListInfo &Buffer, 630 DeclarationName &Name, 631 SourceLocation &NameLoc, 632 const TemplateArgumentListInfo *&TemplateArgs) { 633 if (Id.getKind() == UnqualifiedId::IK_TemplateId) { 634 Buffer.setLAngleLoc(Id.TemplateId->LAngleLoc); 635 Buffer.setRAngleLoc(Id.TemplateId->RAngleLoc); 636 637 ASTTemplateArgsPtr TemplateArgsPtr(SemaRef, 638 Id.TemplateId->getTemplateArgs(), 639 Id.TemplateId->NumArgs); 640 SemaRef.translateTemplateArguments(TemplateArgsPtr, Buffer); 641 TemplateArgsPtr.release(); 642 643 TemplateName TName = 644 Sema::TemplateTy::make(Id.TemplateId->Template).getAsVal<TemplateName>(); 645 646 Name = SemaRef.Context.getNameForTemplate(TName); 647 NameLoc = Id.TemplateId->TemplateNameLoc; 648 TemplateArgs = &Buffer; 649 } else { 650 Name = SemaRef.GetNameFromUnqualifiedId(Id); 651 NameLoc = Id.StartLocation; 652 TemplateArgs = 0; 653 } 654} 655 656/// Decompose the given template name into a list of lookup results. 657/// 658/// The unqualified ID must name a non-dependent template, which can 659/// be more easily tested by checking whether DecomposeUnqualifiedId 660/// found template arguments. 661static void DecomposeTemplateName(LookupResult &R, const UnqualifiedId &Id) { 662 assert(Id.getKind() == UnqualifiedId::IK_TemplateId); 663 TemplateName TName = 664 Sema::TemplateTy::make(Id.TemplateId->Template).getAsVal<TemplateName>(); 665 666 if (TemplateDecl *TD = TName.getAsTemplateDecl()) 667 R.addDecl(TD); 668 else if (OverloadedTemplateStorage *OT = TName.getAsOverloadedTemplate()) 669 for (OverloadedTemplateStorage::iterator I = OT->begin(), E = OT->end(); 670 I != E; ++I) 671 R.addDecl(*I); 672 673 R.resolveKind(); 674} 675 676static bool IsFullyFormedScope(Sema &SemaRef, CXXRecordDecl *Record) { 677 for (CXXRecordDecl::base_class_iterator I = Record->bases_begin(), 678 E = Record->bases_end(); I != E; ++I) { 679 CanQualType BaseT = SemaRef.Context.getCanonicalType((*I).getType()); 680 CanQual<RecordType> BaseRT = BaseT->getAs<RecordType>(); 681 if (!BaseRT) return false; 682 683 CXXRecordDecl *BaseRecord = cast<CXXRecordDecl>(BaseRT->getDecl()); 684 if (!BaseRecord->isDefinition() || 685 !IsFullyFormedScope(SemaRef, BaseRecord)) 686 return false; 687 } 688 689 return true; 690} 691 692/// Determines whether we can lookup this id-expression now or whether 693/// we have to wait until template instantiation is complete. 694static bool IsDependentIdExpression(Sema &SemaRef, const CXXScopeSpec &SS) { 695 DeclContext *DC = SemaRef.computeDeclContext(SS, false); 696 697 // If the qualifier scope isn't computable, it's definitely dependent. 698 if (!DC) return true; 699 700 // If the qualifier scope doesn't name a record, we can always look into it. 701 if (!isa<CXXRecordDecl>(DC)) return false; 702 703 // We can't look into record types unless they're fully-formed. 704 if (!IsFullyFormedScope(SemaRef, cast<CXXRecordDecl>(DC))) return true; 705 706 return false; 707} 708 709/// Determines if the given class is provably not derived from all of 710/// the prospective base classes. 711static bool IsProvablyNotDerivedFrom(Sema &SemaRef, 712 CXXRecordDecl *Record, 713 const llvm::SmallPtrSet<CXXRecordDecl*, 4> &Bases) { 714 if (Bases.count(Record->getCanonicalDecl())) 715 return false; 716 717 RecordDecl *RD = Record->getDefinition(SemaRef.Context); 718 if (!RD) return false; 719 Record = cast<CXXRecordDecl>(RD); 720 721 for (CXXRecordDecl::base_class_iterator I = Record->bases_begin(), 722 E = Record->bases_end(); I != E; ++I) { 723 CanQualType BaseT = SemaRef.Context.getCanonicalType((*I).getType()); 724 CanQual<RecordType> BaseRT = BaseT->getAs<RecordType>(); 725 if (!BaseRT) return false; 726 727 CXXRecordDecl *BaseRecord = cast<CXXRecordDecl>(BaseRT->getDecl()); 728 if (!IsProvablyNotDerivedFrom(SemaRef, BaseRecord, Bases)) 729 return false; 730 } 731 732 return true; 733} 734 735static bool IsInstanceMember(NamedDecl *D) { 736 if (isa<EnumConstantDecl>(D)) 737 return false; 738 739 assert(isa<CXXRecordDecl>(D->getDeclContext()) && 740 "checking whether non-member is instance member"); 741 742 if (isa<FieldDecl>(D)) return true; 743 744 if (isa<CXXMethodDecl>(D)) 745 return !cast<CXXMethodDecl>(D)->isStatic(); 746 747 if (isa<FunctionTemplateDecl>(D)) { 748 D = cast<FunctionTemplateDecl>(D)->getTemplatedDecl(); 749 return !cast<CXXMethodDecl>(D)->isStatic(); 750 } 751 752 return false; 753} 754 755enum IMAKind { 756 /// The reference is definitely not an instance member access. 757 IMA_Static, 758 759 /// The reference may be an implicit instance member access. 760 IMA_Mixed, 761 762 /// The reference may be to an instance member, but it is invalid if 763 /// so, because the context is not an instance method. 764 IMA_Mixed_StaticContext, 765 766 /// The reference may be to an instance member, but it is invalid if 767 /// so, because the context is from an unrelated class. 768 IMA_Mixed_Unrelated, 769 770 /// The reference is definitely an implicit instance member access. 771 IMA_Instance, 772 773 /// The reference may be to an unresolved using declaration. 774 IMA_Unresolved, 775 776 /// The reference may be to an unresolved using declaration and the 777 /// context is not an instance method. 778 IMA_Unresolved_StaticContext, 779 780 /// The reference is to a member of an anonymous structure in a 781 /// non-class context. 782 IMA_AnonymousMember, 783 784 /// All possible referrents are instance members and the current 785 /// context is not an instance method. 786 IMA_Error_StaticContext, 787 788 /// All possible referrents are instance members of an unrelated 789 /// class. 790 IMA_Error_Unrelated 791}; 792 793/// The given lookup names class member(s) and is not being used for 794/// an address-of-member expression. Classify the type of access 795/// according to whether it's possible that this reference names an 796/// instance member. This is best-effort; it is okay to 797/// conservatively answer "yes", in which case some errors will simply 798/// not be caught until template-instantiation. 799static IMAKind ClassifyImplicitMemberAccess(Sema &SemaRef, 800 const LookupResult &R) { 801 assert(!R.empty() && isa<CXXRecordDecl>((*R.begin())->getDeclContext())); 802 803 bool isStaticContext = 804 (!isa<CXXMethodDecl>(SemaRef.CurContext) || 805 cast<CXXMethodDecl>(SemaRef.CurContext)->isStatic()); 806 807 if (R.isUnresolvableResult()) 808 return isStaticContext ? IMA_Unresolved_StaticContext : IMA_Unresolved; 809 810 // Collect all the declaring classes of instance members we find. 811 bool hasNonInstance = false; 812 llvm::SmallPtrSet<CXXRecordDecl*, 4> Classes; 813 for (LookupResult::iterator I = R.begin(), E = R.end(); I != E; ++I) { 814 NamedDecl *D = (*I)->getUnderlyingDecl(); 815 if (IsInstanceMember(D)) { 816 CXXRecordDecl *R = cast<CXXRecordDecl>(D->getDeclContext()); 817 818 // If this is a member of an anonymous record, move out to the 819 // innermost non-anonymous struct or union. If there isn't one, 820 // that's a special case. 821 while (R->isAnonymousStructOrUnion()) { 822 R = dyn_cast<CXXRecordDecl>(R->getParent()); 823 if (!R) return IMA_AnonymousMember; 824 } 825 Classes.insert(R->getCanonicalDecl()); 826 } 827 else 828 hasNonInstance = true; 829 } 830 831 // If we didn't find any instance members, it can't be an implicit 832 // member reference. 833 if (Classes.empty()) 834 return IMA_Static; 835 836 // If the current context is not an instance method, it can't be 837 // an implicit member reference. 838 if (isStaticContext) 839 return (hasNonInstance ? IMA_Mixed_StaticContext : IMA_Error_StaticContext); 840 841 // If we can prove that the current context is unrelated to all the 842 // declaring classes, it can't be an implicit member reference (in 843 // which case it's an error if any of those members are selected). 844 if (IsProvablyNotDerivedFrom(SemaRef, 845 cast<CXXMethodDecl>(SemaRef.CurContext)->getParent(), 846 Classes)) 847 return (hasNonInstance ? IMA_Mixed_Unrelated : IMA_Error_Unrelated); 848 849 return (hasNonInstance ? IMA_Mixed : IMA_Instance); 850} 851 852/// Diagnose a reference to a field with no object available. 853static void DiagnoseInstanceReference(Sema &SemaRef, 854 const CXXScopeSpec &SS, 855 const LookupResult &R) { 856 SourceLocation Loc = R.getNameLoc(); 857 SourceRange Range(Loc); 858 if (SS.isSet()) Range.setBegin(SS.getRange().getBegin()); 859 860 if (R.getAsSingle<FieldDecl>()) { 861 if (CXXMethodDecl *MD = dyn_cast<CXXMethodDecl>(SemaRef.CurContext)) { 862 if (MD->isStatic()) { 863 // "invalid use of member 'x' in static member function" 864 SemaRef.Diag(Loc, diag::err_invalid_member_use_in_static_method) 865 << Range << R.getLookupName(); 866 return; 867 } 868 } 869 870 SemaRef.Diag(Loc, diag::err_invalid_non_static_member_use) 871 << R.getLookupName() << Range; 872 return; 873 } 874 875 SemaRef.Diag(Loc, diag::err_member_call_without_object) << Range; 876} 877 878Sema::OwningExprResult Sema::ActOnIdExpression(Scope *S, 879 const CXXScopeSpec &SS, 880 UnqualifiedId &Id, 881 bool HasTrailingLParen, 882 bool isAddressOfOperand) { 883 assert(!(isAddressOfOperand && HasTrailingLParen) && 884 "cannot be direct & operand and have a trailing lparen"); 885 886 if (SS.isInvalid()) 887 return ExprError(); 888 889 TemplateArgumentListInfo TemplateArgsBuffer; 890 891 // Decompose the UnqualifiedId into the following data. 892 DeclarationName Name; 893 SourceLocation NameLoc; 894 const TemplateArgumentListInfo *TemplateArgs; 895 DecomposeUnqualifiedId(*this, Id, TemplateArgsBuffer, 896 Name, NameLoc, TemplateArgs); 897 898 IdentifierInfo *II = Name.getAsIdentifierInfo(); 899 900 // C++ [temp.dep.expr]p3: 901 // An id-expression is type-dependent if it contains: 902 // -- a nested-name-specifier that contains a class-name that 903 // names a dependent type. 904 // Determine whether this is a member of an unknown specialization; 905 // we need to handle these differently. 906 if (SS.isSet() && IsDependentIdExpression(*this, SS)) { 907 return ActOnDependentIdExpression(SS, Name, NameLoc, 908 isAddressOfOperand, 909 TemplateArgs); 910 } 911 912 // Perform the required lookup. 913 LookupResult R(*this, Name, NameLoc, LookupOrdinaryName); 914 if (TemplateArgs) { 915 // Just re-use the lookup done by isTemplateName. 916 DecomposeTemplateName(R, Id); 917 } else { 918 LookupParsedName(R, S, &SS, true); 919 920 // If this reference is in an Objective-C method, then we need to do 921 // some special Objective-C lookup, too. 922 if (!SS.isSet() && II && getCurMethodDecl()) { 923 OwningExprResult E(LookupInObjCMethod(R, S, II)); 924 if (E.isInvalid()) 925 return ExprError(); 926 927 Expr *Ex = E.takeAs<Expr>(); 928 if (Ex) return Owned(Ex); 929 } 930 } 931 932 if (R.isAmbiguous()) 933 return ExprError(); 934 935 // Determine whether this name might be a candidate for 936 // argument-dependent lookup. 937 bool ADL = UseArgumentDependentLookup(SS, R, HasTrailingLParen); 938 939 if (R.empty() && !ADL) { 940 // Otherwise, this could be an implicitly declared function reference (legal 941 // in C90, extension in C99, forbidden in C++). 942 if (HasTrailingLParen && II && !getLangOptions().CPlusPlus) { 943 NamedDecl *D = ImplicitlyDefineFunction(NameLoc, *II, S); 944 if (D) R.addDecl(D); 945 } 946 947 // If this name wasn't predeclared and if this is not a function 948 // call, diagnose the problem. 949 if (R.empty()) { 950 if (!SS.isEmpty()) 951 return ExprError(Diag(NameLoc, diag::err_no_member) 952 << Name << computeDeclContext(SS, false) 953 << SS.getRange()); 954 else if (Name.getNameKind() == DeclarationName::CXXOperatorName || 955 Name.getNameKind() == DeclarationName::CXXLiteralOperatorName || 956 Name.getNameKind() == DeclarationName::CXXConversionFunctionName) 957 return ExprError(Diag(NameLoc, diag::err_undeclared_use) 958 << Name); 959 else 960 return ExprError(Diag(NameLoc, diag::err_undeclared_var_use) << Name); 961 } 962 } 963 964 // This is guaranteed from this point on. 965 assert(!R.empty() || ADL); 966 967 if (VarDecl *Var = R.getAsSingle<VarDecl>()) { 968 // Warn about constructs like: 969 // if (void *X = foo()) { ... } else { X }. 970 // In the else block, the pointer is always false. 971 972 if (Var->isDeclaredInCondition() && Var->getType()->isScalarType()) { 973 Scope *CheckS = S; 974 while (CheckS && CheckS->getControlParent()) { 975 if (CheckS->isWithinElse() && 976 CheckS->getControlParent()->isDeclScope(DeclPtrTy::make(Var))) { 977 ExprError(Diag(NameLoc, diag::warn_value_always_zero) 978 << Var->getDeclName() 979 << (Var->getType()->isPointerType()? 2 : 980 Var->getType()->isBooleanType()? 1 : 0)); 981 break; 982 } 983 984 // Move to the parent of this scope. 985 CheckS = CheckS->getParent(); 986 } 987 } 988 } else if (FunctionDecl *Func = R.getAsSingle<FunctionDecl>()) { 989 if (!getLangOptions().CPlusPlus && !Func->hasPrototype()) { 990 // C99 DR 316 says that, if a function type comes from a 991 // function definition (without a prototype), that type is only 992 // used for checking compatibility. Therefore, when referencing 993 // the function, we pretend that we don't have the full function 994 // type. 995 if (DiagnoseUseOfDecl(Func, NameLoc)) 996 return ExprError(); 997 998 QualType T = Func->getType(); 999 QualType NoProtoType = T; 1000 if (const FunctionProtoType *Proto = T->getAs<FunctionProtoType>()) 1001 NoProtoType = Context.getFunctionNoProtoType(Proto->getResultType()); 1002 return BuildDeclRefExpr(Func, NoProtoType, NameLoc, &SS); 1003 } 1004 } 1005 1006 // Check whether this might be a C++ implicit instance member access. 1007 // C++ [expr.prim.general]p6: 1008 // Within the definition of a non-static member function, an 1009 // identifier that names a non-static member is transformed to a 1010 // class member access expression. 1011 // But note that &SomeClass::foo is grammatically distinct, even 1012 // though we don't parse it that way. 1013 if (!R.empty() && (*R.begin())->getDeclContext()->isRecord()) { 1014 bool isAbstractMemberPointer = (isAddressOfOperand && !SS.isEmpty()); 1015 1016 if (!isAbstractMemberPointer) { 1017 switch (ClassifyImplicitMemberAccess(*this, R)) { 1018 case IMA_Instance: 1019 return BuildImplicitMemberExpr(SS, R, TemplateArgs, true); 1020 1021 case IMA_AnonymousMember: 1022 assert(R.isSingleResult()); 1023 return BuildAnonymousStructUnionMemberReference(R.getNameLoc(), 1024 R.getAsSingle<FieldDecl>()); 1025 1026 case IMA_Mixed: 1027 case IMA_Mixed_Unrelated: 1028 case IMA_Unresolved: 1029 return BuildImplicitMemberExpr(SS, R, TemplateArgs, false); 1030 1031 case IMA_Static: 1032 case IMA_Mixed_StaticContext: 1033 case IMA_Unresolved_StaticContext: 1034 break; 1035 1036 case IMA_Error_StaticContext: 1037 case IMA_Error_Unrelated: 1038 DiagnoseInstanceReference(*this, SS, R); 1039 return ExprError(); 1040 } 1041 } 1042 } 1043 1044 if (TemplateArgs) 1045 return BuildTemplateIdExpr(SS, R, ADL, *TemplateArgs); 1046 1047 return BuildDeclarationNameExpr(SS, R, ADL); 1048} 1049 1050/// BuildQualifiedDeclarationNameExpr - Build a C++ qualified 1051/// declaration name, generally during template instantiation. 1052/// There's a large number of things which don't need to be done along 1053/// this path. 1054Sema::OwningExprResult 1055Sema::BuildQualifiedDeclarationNameExpr(const CXXScopeSpec &SS, 1056 DeclarationName Name, 1057 SourceLocation NameLoc) { 1058 DeclContext *DC; 1059 if (!(DC = computeDeclContext(SS, false)) || 1060 DC->isDependentContext() || 1061 RequireCompleteDeclContext(SS)) 1062 return BuildDependentDeclRefExpr(SS, Name, NameLoc, 0); 1063 1064 LookupResult R(*this, Name, NameLoc, LookupOrdinaryName); 1065 LookupQualifiedName(R, DC); 1066 1067 if (R.isAmbiguous()) 1068 return ExprError(); 1069 1070 if (R.empty()) { 1071 Diag(NameLoc, diag::err_no_member) << Name << DC << SS.getRange(); 1072 return ExprError(); 1073 } 1074 1075 return BuildDeclarationNameExpr(SS, R, /*ADL*/ false); 1076} 1077 1078/// LookupInObjCMethod - The parser has read a name in, and Sema has 1079/// detected that we're currently inside an ObjC method. Perform some 1080/// additional lookup. 1081/// 1082/// Ideally, most of this would be done by lookup, but there's 1083/// actually quite a lot of extra work involved. 1084/// 1085/// Returns a null sentinel to indicate trivial success. 1086Sema::OwningExprResult 1087Sema::LookupInObjCMethod(LookupResult &Lookup, Scope *S, 1088 IdentifierInfo *II) { 1089 SourceLocation Loc = Lookup.getNameLoc(); 1090 1091 // There are two cases to handle here. 1) scoped lookup could have failed, 1092 // in which case we should look for an ivar. 2) scoped lookup could have 1093 // found a decl, but that decl is outside the current instance method (i.e. 1094 // a global variable). In these two cases, we do a lookup for an ivar with 1095 // this name, if the lookup sucedes, we replace it our current decl. 1096 1097 // If we're in a class method, we don't normally want to look for 1098 // ivars. But if we don't find anything else, and there's an 1099 // ivar, that's an error. 1100 bool IsClassMethod = getCurMethodDecl()->isClassMethod(); 1101 1102 bool LookForIvars; 1103 if (Lookup.empty()) 1104 LookForIvars = true; 1105 else if (IsClassMethod) 1106 LookForIvars = false; 1107 else 1108 LookForIvars = (Lookup.isSingleResult() && 1109 Lookup.getFoundDecl()->isDefinedOutsideFunctionOrMethod()); 1110 1111 if (LookForIvars) { 1112 ObjCInterfaceDecl *IFace = getCurMethodDecl()->getClassInterface(); 1113 ObjCInterfaceDecl *ClassDeclared; 1114 if (ObjCIvarDecl *IV = IFace->lookupInstanceVariable(II, ClassDeclared)) { 1115 // Diagnose using an ivar in a class method. 1116 if (IsClassMethod) 1117 return ExprError(Diag(Loc, diag::error_ivar_use_in_class_method) 1118 << IV->getDeclName()); 1119 1120 // If we're referencing an invalid decl, just return this as a silent 1121 // error node. The error diagnostic was already emitted on the decl. 1122 if (IV->isInvalidDecl()) 1123 return ExprError(); 1124 1125 // Check if referencing a field with __attribute__((deprecated)). 1126 if (DiagnoseUseOfDecl(IV, Loc)) 1127 return ExprError(); 1128 1129 // Diagnose the use of an ivar outside of the declaring class. 1130 if (IV->getAccessControl() == ObjCIvarDecl::Private && 1131 ClassDeclared != IFace) 1132 Diag(Loc, diag::error_private_ivar_access) << IV->getDeclName(); 1133 1134 // FIXME: This should use a new expr for a direct reference, don't 1135 // turn this into Self->ivar, just return a BareIVarExpr or something. 1136 IdentifierInfo &II = Context.Idents.get("self"); 1137 UnqualifiedId SelfName; 1138 SelfName.setIdentifier(&II, SourceLocation()); 1139 CXXScopeSpec SelfScopeSpec; 1140 OwningExprResult SelfExpr = ActOnIdExpression(S, SelfScopeSpec, 1141 SelfName, false, false); 1142 MarkDeclarationReferenced(Loc, IV); 1143 return Owned(new (Context) 1144 ObjCIvarRefExpr(IV, IV->getType(), Loc, 1145 SelfExpr.takeAs<Expr>(), true, true)); 1146 } 1147 } else if (getCurMethodDecl()->isInstanceMethod()) { 1148 // We should warn if a local variable hides an ivar. 1149 ObjCInterfaceDecl *IFace = getCurMethodDecl()->getClassInterface(); 1150 ObjCInterfaceDecl *ClassDeclared; 1151 if (ObjCIvarDecl *IV = IFace->lookupInstanceVariable(II, ClassDeclared)) { 1152 if (IV->getAccessControl() != ObjCIvarDecl::Private || 1153 IFace == ClassDeclared) 1154 Diag(Loc, diag::warn_ivar_use_hidden) << IV->getDeclName(); 1155 } 1156 } 1157 1158 // Needed to implement property "super.method" notation. 1159 if (Lookup.empty() && II->isStr("super")) { 1160 QualType T; 1161 1162 if (getCurMethodDecl()->isInstanceMethod()) 1163 T = Context.getObjCObjectPointerType(Context.getObjCInterfaceType( 1164 getCurMethodDecl()->getClassInterface())); 1165 else 1166 T = Context.getObjCClassType(); 1167 return Owned(new (Context) ObjCSuperExpr(Loc, T)); 1168 } 1169 1170 // Sentinel value saying that we didn't do anything special. 1171 return Owned((Expr*) 0); 1172} 1173 1174/// \brief Cast member's object to its own class if necessary. 1175bool 1176Sema::PerformObjectMemberConversion(Expr *&From, NamedDecl *Member) { 1177 if (FieldDecl *FD = dyn_cast<FieldDecl>(Member)) 1178 if (CXXRecordDecl *RD = 1179 dyn_cast<CXXRecordDecl>(FD->getDeclContext())) { 1180 QualType DestType = 1181 Context.getCanonicalType(Context.getTypeDeclType(RD)); 1182 if (DestType->isDependentType() || From->getType()->isDependentType()) 1183 return false; 1184 QualType FromRecordType = From->getType(); 1185 QualType DestRecordType = DestType; 1186 if (FromRecordType->getAs<PointerType>()) { 1187 DestType = Context.getPointerType(DestType); 1188 FromRecordType = FromRecordType->getPointeeType(); 1189 } 1190 if (!Context.hasSameUnqualifiedType(FromRecordType, DestRecordType) && 1191 CheckDerivedToBaseConversion(FromRecordType, 1192 DestRecordType, 1193 From->getSourceRange().getBegin(), 1194 From->getSourceRange())) 1195 return true; 1196 ImpCastExprToType(From, DestType, CastExpr::CK_DerivedToBase, 1197 /*isLvalue=*/true); 1198 } 1199 return false; 1200} 1201 1202/// \brief Build a MemberExpr AST node. 1203static MemberExpr *BuildMemberExpr(ASTContext &C, Expr *Base, bool isArrow, 1204 const CXXScopeSpec &SS, NamedDecl *Member, 1205 SourceLocation Loc, QualType Ty, 1206 const TemplateArgumentListInfo *TemplateArgs = 0) { 1207 NestedNameSpecifier *Qualifier = 0; 1208 SourceRange QualifierRange; 1209 if (SS.isSet()) { 1210 Qualifier = (NestedNameSpecifier *) SS.getScopeRep(); 1211 QualifierRange = SS.getRange(); 1212 } 1213 1214 return MemberExpr::Create(C, Base, isArrow, Qualifier, QualifierRange, 1215 Member, Loc, TemplateArgs, Ty); 1216} 1217 1218/// Builds an implicit member access expression. The current context 1219/// is known to be an instance method, and the given unqualified lookup 1220/// set is known to contain only instance members, at least one of which 1221/// is from an appropriate type. 1222Sema::OwningExprResult 1223Sema::BuildImplicitMemberExpr(const CXXScopeSpec &SS, 1224 LookupResult &R, 1225 const TemplateArgumentListInfo *TemplateArgs, 1226 bool IsKnownInstance) { 1227 assert(!R.empty() && !R.isAmbiguous()); 1228 1229 SourceLocation Loc = R.getNameLoc(); 1230 1231 // We may have found a field within an anonymous union or struct 1232 // (C++ [class.union]). 1233 // FIXME: This needs to happen post-isImplicitMemberReference? 1234 // FIXME: template-ids inside anonymous structs? 1235 if (FieldDecl *FD = R.getAsSingle<FieldDecl>()) 1236 if (cast<RecordDecl>(FD->getDeclContext())->isAnonymousStructOrUnion()) 1237 return BuildAnonymousStructUnionMemberReference(Loc, FD); 1238 1239 // If this is known to be an instance access, go ahead and build a 1240 // 'this' expression now. 1241 QualType ThisType = cast<CXXMethodDecl>(CurContext)->getThisType(Context); 1242 Expr *This = 0; // null signifies implicit access 1243 if (IsKnownInstance) { 1244 This = new (Context) CXXThisExpr(SourceLocation(), ThisType); 1245 } 1246 1247 return BuildMemberReferenceExpr(ExprArg(*this, This), ThisType, 1248 /*OpLoc*/ SourceLocation(), 1249 /*IsArrow*/ true, 1250 SS, R, TemplateArgs); 1251} 1252 1253bool Sema::UseArgumentDependentLookup(const CXXScopeSpec &SS, 1254 const LookupResult &R, 1255 bool HasTrailingLParen) { 1256 // Only when used directly as the postfix-expression of a call. 1257 if (!HasTrailingLParen) 1258 return false; 1259 1260 // Never if a scope specifier was provided. 1261 if (SS.isSet()) 1262 return false; 1263 1264 // Only in C++ or ObjC++. 1265 if (!getLangOptions().CPlusPlus) 1266 return false; 1267 1268 // Turn off ADL when we find certain kinds of declarations during 1269 // normal lookup: 1270 for (LookupResult::iterator I = R.begin(), E = R.end(); I != E; ++I) { 1271 NamedDecl *D = *I; 1272 1273 // C++0x [basic.lookup.argdep]p3: 1274 // -- a declaration of a class member 1275 // Since using decls preserve this property, we check this on the 1276 // original decl. 1277 if (D->getDeclContext()->isRecord()) 1278 return false; 1279 1280 // C++0x [basic.lookup.argdep]p3: 1281 // -- a block-scope function declaration that is not a 1282 // using-declaration 1283 // NOTE: we also trigger this for function templates (in fact, we 1284 // don't check the decl type at all, since all other decl types 1285 // turn off ADL anyway). 1286 if (isa<UsingShadowDecl>(D)) 1287 D = cast<UsingShadowDecl>(D)->getTargetDecl(); 1288 else if (D->getDeclContext()->isFunctionOrMethod()) 1289 return false; 1290 1291 // C++0x [basic.lookup.argdep]p3: 1292 // -- a declaration that is neither a function or a function 1293 // template 1294 // And also for builtin functions. 1295 if (isa<FunctionDecl>(D)) { 1296 FunctionDecl *FDecl = cast<FunctionDecl>(D); 1297 1298 // But also builtin functions. 1299 if (FDecl->getBuiltinID() && FDecl->isImplicit()) 1300 return false; 1301 } else if (!isa<FunctionTemplateDecl>(D)) 1302 return false; 1303 } 1304 1305 return true; 1306} 1307 1308 1309/// Diagnoses obvious problems with the use of the given declaration 1310/// as an expression. This is only actually called for lookups that 1311/// were not overloaded, and it doesn't promise that the declaration 1312/// will in fact be used. 1313static bool CheckDeclInExpr(Sema &S, SourceLocation Loc, NamedDecl *D) { 1314 if (isa<TypedefDecl>(D)) { 1315 S.Diag(Loc, diag::err_unexpected_typedef) << D->getDeclName(); 1316 return true; 1317 } 1318 1319 if (isa<ObjCInterfaceDecl>(D)) { 1320 S.Diag(Loc, diag::err_unexpected_interface) << D->getDeclName(); 1321 return true; 1322 } 1323 1324 if (isa<NamespaceDecl>(D)) { 1325 S.Diag(Loc, diag::err_unexpected_namespace) << D->getDeclName(); 1326 return true; 1327 } 1328 1329 return false; 1330} 1331 1332Sema::OwningExprResult 1333Sema::BuildDeclarationNameExpr(const CXXScopeSpec &SS, 1334 LookupResult &R, 1335 bool NeedsADL) { 1336 // If this isn't an overloaded result and we don't need ADL, just 1337 // build an ordinary singleton decl ref. 1338 if (!NeedsADL && !R.isOverloadedResult()) 1339 return BuildDeclarationNameExpr(SS, R.getNameLoc(), R.getFoundDecl()); 1340 1341 // We only need to check the declaration if there's exactly one 1342 // result, because in the overloaded case the results can only be 1343 // functions and function templates. 1344 if (R.isSingleResult() && 1345 CheckDeclInExpr(*this, R.getNameLoc(), R.getFoundDecl())) 1346 return ExprError(); 1347 1348 bool Dependent 1349 = UnresolvedLookupExpr::ComputeDependence(R.begin(), R.end(), 0); 1350 UnresolvedLookupExpr *ULE 1351 = UnresolvedLookupExpr::Create(Context, Dependent, 1352 (NestedNameSpecifier*) SS.getScopeRep(), 1353 SS.getRange(), 1354 R.getLookupName(), R.getNameLoc(), 1355 NeedsADL, R.isOverloadedResult()); 1356 for (LookupResult::iterator I = R.begin(), E = R.end(); I != E; ++I) 1357 ULE->addDecl(*I); 1358 1359 return Owned(ULE); 1360} 1361 1362 1363/// \brief Complete semantic analysis for a reference to the given declaration. 1364Sema::OwningExprResult 1365Sema::BuildDeclarationNameExpr(const CXXScopeSpec &SS, 1366 SourceLocation Loc, NamedDecl *D) { 1367 assert(D && "Cannot refer to a NULL declaration"); 1368 assert(!isa<FunctionTemplateDecl>(D) && 1369 "Cannot refer unambiguously to a function template"); 1370 DeclarationName Name = D->getDeclName(); 1371 1372 if (CheckDeclInExpr(*this, Loc, D)) 1373 return ExprError(); 1374 1375 if (TemplateDecl *Template = dyn_cast<TemplateDecl>(D)) { 1376 // Specifically diagnose references to class templates that are missing 1377 // a template argument list. 1378 Diag(Loc, diag::err_template_decl_ref) 1379 << Template << SS.getRange(); 1380 Diag(Template->getLocation(), diag::note_template_decl_here); 1381 return ExprError(); 1382 } 1383 1384 // Make sure that we're referring to a value. 1385 ValueDecl *VD = dyn_cast<ValueDecl>(D); 1386 if (!VD) { 1387 Diag(Loc, diag::err_ref_non_value) 1388 << D << SS.getRange(); 1389 Diag(D->getLocation(), diag::note_previous_decl); 1390 return ExprError(); 1391 } 1392 1393 // Check whether this declaration can be used. Note that we suppress 1394 // this check when we're going to perform argument-dependent lookup 1395 // on this function name, because this might not be the function 1396 // that overload resolution actually selects. 1397 if (DiagnoseUseOfDecl(VD, Loc)) 1398 return ExprError(); 1399 1400 // Only create DeclRefExpr's for valid Decl's. 1401 if (VD->isInvalidDecl()) 1402 return ExprError(); 1403 1404 // If the identifier reference is inside a block, and it refers to a value 1405 // that is outside the block, create a BlockDeclRefExpr instead of a 1406 // DeclRefExpr. This ensures the value is treated as a copy-in snapshot when 1407 // the block is formed. 1408 // 1409 // We do not do this for things like enum constants, global variables, etc, 1410 // as they do not get snapshotted. 1411 // 1412 if (CurBlock && ShouldSnapshotBlockValueReference(CurBlock, VD)) { 1413 MarkDeclarationReferenced(Loc, VD); 1414 QualType ExprTy = VD->getType().getNonReferenceType(); 1415 // The BlocksAttr indicates the variable is bound by-reference. 1416 if (VD->getAttr<BlocksAttr>()) 1417 return Owned(new (Context) BlockDeclRefExpr(VD, ExprTy, Loc, true)); 1418 // This is to record that a 'const' was actually synthesize and added. 1419 bool constAdded = !ExprTy.isConstQualified(); 1420 // Variable will be bound by-copy, make it const within the closure. 1421 1422 ExprTy.addConst(); 1423 return Owned(new (Context) BlockDeclRefExpr(VD, ExprTy, Loc, false, 1424 constAdded)); 1425 } 1426 // If this reference is not in a block or if the referenced variable is 1427 // within the block, create a normal DeclRefExpr. 1428 1429 return BuildDeclRefExpr(VD, VD->getType().getNonReferenceType(), Loc, &SS); 1430} 1431 1432Sema::OwningExprResult Sema::ActOnPredefinedExpr(SourceLocation Loc, 1433 tok::TokenKind Kind) { 1434 PredefinedExpr::IdentType IT; 1435 1436 switch (Kind) { 1437 default: assert(0 && "Unknown simple primary expr!"); 1438 case tok::kw___func__: IT = PredefinedExpr::Func; break; // [C99 6.4.2.2] 1439 case tok::kw___FUNCTION__: IT = PredefinedExpr::Function; break; 1440 case tok::kw___PRETTY_FUNCTION__: IT = PredefinedExpr::PrettyFunction; break; 1441 } 1442 1443 // Pre-defined identifiers are of type char[x], where x is the length of the 1444 // string. 1445 1446 Decl *currentDecl = getCurFunctionOrMethodDecl(); 1447 if (!currentDecl) { 1448 Diag(Loc, diag::ext_predef_outside_function); 1449 currentDecl = Context.getTranslationUnitDecl(); 1450 } 1451 1452 QualType ResTy; 1453 if (cast<DeclContext>(currentDecl)->isDependentContext()) { 1454 ResTy = Context.DependentTy; 1455 } else { 1456 unsigned Length = 1457 PredefinedExpr::ComputeName(Context, IT, currentDecl).length(); 1458 1459 llvm::APInt LengthI(32, Length + 1); 1460 ResTy = Context.CharTy.withConst(); 1461 ResTy = Context.getConstantArrayType(ResTy, LengthI, ArrayType::Normal, 0); 1462 } 1463 return Owned(new (Context) PredefinedExpr(Loc, ResTy, IT)); 1464} 1465 1466Sema::OwningExprResult Sema::ActOnCharacterConstant(const Token &Tok) { 1467 llvm::SmallString<16> CharBuffer; 1468 CharBuffer.resize(Tok.getLength()); 1469 const char *ThisTokBegin = &CharBuffer[0]; 1470 unsigned ActualLength = PP.getSpelling(Tok, ThisTokBegin); 1471 1472 CharLiteralParser Literal(ThisTokBegin, ThisTokBegin+ActualLength, 1473 Tok.getLocation(), PP); 1474 if (Literal.hadError()) 1475 return ExprError(); 1476 1477 QualType type = getLangOptions().CPlusPlus ? Context.CharTy : Context.IntTy; 1478 1479 return Owned(new (Context) CharacterLiteral(Literal.getValue(), 1480 Literal.isWide(), 1481 type, Tok.getLocation())); 1482} 1483 1484Action::OwningExprResult Sema::ActOnNumericConstant(const Token &Tok) { 1485 // Fast path for a single digit (which is quite common). A single digit 1486 // cannot have a trigraph, escaped newline, radix prefix, or type suffix. 1487 if (Tok.getLength() == 1) { 1488 const char Val = PP.getSpellingOfSingleCharacterNumericConstant(Tok); 1489 unsigned IntSize = Context.Target.getIntWidth(); 1490 return Owned(new (Context) IntegerLiteral(llvm::APInt(IntSize, Val-'0'), 1491 Context.IntTy, Tok.getLocation())); 1492 } 1493 1494 llvm::SmallString<512> IntegerBuffer; 1495 // Add padding so that NumericLiteralParser can overread by one character. 1496 IntegerBuffer.resize(Tok.getLength()+1); 1497 const char *ThisTokBegin = &IntegerBuffer[0]; 1498 1499 // Get the spelling of the token, which eliminates trigraphs, etc. 1500 unsigned ActualLength = PP.getSpelling(Tok, ThisTokBegin); 1501 1502 NumericLiteralParser Literal(ThisTokBegin, ThisTokBegin+ActualLength, 1503 Tok.getLocation(), PP); 1504 if (Literal.hadError) 1505 return ExprError(); 1506 1507 Expr *Res; 1508 1509 if (Literal.isFloatingLiteral()) { 1510 QualType Ty; 1511 if (Literal.isFloat) 1512 Ty = Context.FloatTy; 1513 else if (!Literal.isLong) 1514 Ty = Context.DoubleTy; 1515 else 1516 Ty = Context.LongDoubleTy; 1517 1518 const llvm::fltSemantics &Format = Context.getFloatTypeSemantics(Ty); 1519 1520 // isExact will be set by GetFloatValue(). 1521 bool isExact = false; 1522 llvm::APFloat Val = Literal.GetFloatValue(Format, &isExact); 1523 Res = new (Context) FloatingLiteral(Val, isExact, Ty, Tok.getLocation()); 1524 1525 } else if (!Literal.isIntegerLiteral()) { 1526 return ExprError(); 1527 } else { 1528 QualType Ty; 1529 1530 // long long is a C99 feature. 1531 if (!getLangOptions().C99 && !getLangOptions().CPlusPlus0x && 1532 Literal.isLongLong) 1533 Diag(Tok.getLocation(), diag::ext_longlong); 1534 1535 // Get the value in the widest-possible width. 1536 llvm::APInt ResultVal(Context.Target.getIntMaxTWidth(), 0); 1537 1538 if (Literal.GetIntegerValue(ResultVal)) { 1539 // If this value didn't fit into uintmax_t, warn and force to ull. 1540 Diag(Tok.getLocation(), diag::warn_integer_too_large); 1541 Ty = Context.UnsignedLongLongTy; 1542 assert(Context.getTypeSize(Ty) == ResultVal.getBitWidth() && 1543 "long long is not intmax_t?"); 1544 } else { 1545 // If this value fits into a ULL, try to figure out what else it fits into 1546 // according to the rules of C99 6.4.4.1p5. 1547 1548 // Octal, Hexadecimal, and integers with a U suffix are allowed to 1549 // be an unsigned int. 1550 bool AllowUnsigned = Literal.isUnsigned || Literal.getRadix() != 10; 1551 1552 // Check from smallest to largest, picking the smallest type we can. 1553 unsigned Width = 0; 1554 if (!Literal.isLong && !Literal.isLongLong) { 1555 // Are int/unsigned possibilities? 1556 unsigned IntSize = Context.Target.getIntWidth(); 1557 1558 // Does it fit in a unsigned int? 1559 if (ResultVal.isIntN(IntSize)) { 1560 // Does it fit in a signed int? 1561 if (!Literal.isUnsigned && ResultVal[IntSize-1] == 0) 1562 Ty = Context.IntTy; 1563 else if (AllowUnsigned) 1564 Ty = Context.UnsignedIntTy; 1565 Width = IntSize; 1566 } 1567 } 1568 1569 // Are long/unsigned long possibilities? 1570 if (Ty.isNull() && !Literal.isLongLong) { 1571 unsigned LongSize = Context.Target.getLongWidth(); 1572 1573 // Does it fit in a unsigned long? 1574 if (ResultVal.isIntN(LongSize)) { 1575 // Does it fit in a signed long? 1576 if (!Literal.isUnsigned && ResultVal[LongSize-1] == 0) 1577 Ty = Context.LongTy; 1578 else if (AllowUnsigned) 1579 Ty = Context.UnsignedLongTy; 1580 Width = LongSize; 1581 } 1582 } 1583 1584 // Finally, check long long if needed. 1585 if (Ty.isNull()) { 1586 unsigned LongLongSize = Context.Target.getLongLongWidth(); 1587 1588 // Does it fit in a unsigned long long? 1589 if (ResultVal.isIntN(LongLongSize)) { 1590 // Does it fit in a signed long long? 1591 if (!Literal.isUnsigned && ResultVal[LongLongSize-1] == 0) 1592 Ty = Context.LongLongTy; 1593 else if (AllowUnsigned) 1594 Ty = Context.UnsignedLongLongTy; 1595 Width = LongLongSize; 1596 } 1597 } 1598 1599 // If we still couldn't decide a type, we probably have something that 1600 // does not fit in a signed long long, but has no U suffix. 1601 if (Ty.isNull()) { 1602 Diag(Tok.getLocation(), diag::warn_integer_too_large_for_signed); 1603 Ty = Context.UnsignedLongLongTy; 1604 Width = Context.Target.getLongLongWidth(); 1605 } 1606 1607 if (ResultVal.getBitWidth() != Width) 1608 ResultVal.trunc(Width); 1609 } 1610 Res = new (Context) IntegerLiteral(ResultVal, Ty, Tok.getLocation()); 1611 } 1612 1613 // If this is an imaginary literal, create the ImaginaryLiteral wrapper. 1614 if (Literal.isImaginary) 1615 Res = new (Context) ImaginaryLiteral(Res, 1616 Context.getComplexType(Res->getType())); 1617 1618 return Owned(Res); 1619} 1620 1621Action::OwningExprResult Sema::ActOnParenExpr(SourceLocation L, 1622 SourceLocation R, ExprArg Val) { 1623 Expr *E = Val.takeAs<Expr>(); 1624 assert((E != 0) && "ActOnParenExpr() missing expr"); 1625 return Owned(new (Context) ParenExpr(L, R, E)); 1626} 1627 1628/// The UsualUnaryConversions() function is *not* called by this routine. 1629/// See C99 6.3.2.1p[2-4] for more details. 1630bool Sema::CheckSizeOfAlignOfOperand(QualType exprType, 1631 SourceLocation OpLoc, 1632 const SourceRange &ExprRange, 1633 bool isSizeof) { 1634 if (exprType->isDependentType()) 1635 return false; 1636 1637 // C++ [expr.sizeof]p2: "When applied to a reference or a reference type, 1638 // the result is the size of the referenced type." 1639 // C++ [expr.alignof]p3: "When alignof is applied to a reference type, the 1640 // result shall be the alignment of the referenced type." 1641 if (const ReferenceType *Ref = exprType->getAs<ReferenceType>()) 1642 exprType = Ref->getPointeeType(); 1643 1644 // C99 6.5.3.4p1: 1645 if (exprType->isFunctionType()) { 1646 // alignof(function) is allowed as an extension. 1647 if (isSizeof) 1648 Diag(OpLoc, diag::ext_sizeof_function_type) << ExprRange; 1649 return false; 1650 } 1651 1652 // Allow sizeof(void)/alignof(void) as an extension. 1653 if (exprType->isVoidType()) { 1654 Diag(OpLoc, diag::ext_sizeof_void_type) 1655 << (isSizeof ? "sizeof" : "__alignof") << ExprRange; 1656 return false; 1657 } 1658 1659 if (RequireCompleteType(OpLoc, exprType, 1660 isSizeof ? diag::err_sizeof_incomplete_type : 1661 PDiag(diag::err_alignof_incomplete_type) 1662 << ExprRange)) 1663 return true; 1664 1665 // Reject sizeof(interface) and sizeof(interface<proto>) in 64-bit mode. 1666 if (LangOpts.ObjCNonFragileABI && exprType->isObjCInterfaceType()) { 1667 Diag(OpLoc, diag::err_sizeof_nonfragile_interface) 1668 << exprType << isSizeof << ExprRange; 1669 return true; 1670 } 1671 1672 return false; 1673} 1674 1675bool Sema::CheckAlignOfExpr(Expr *E, SourceLocation OpLoc, 1676 const SourceRange &ExprRange) { 1677 E = E->IgnoreParens(); 1678 1679 // alignof decl is always ok. 1680 if (isa<DeclRefExpr>(E)) 1681 return false; 1682 1683 // Cannot know anything else if the expression is dependent. 1684 if (E->isTypeDependent()) 1685 return false; 1686 1687 if (E->getBitField()) { 1688 Diag(OpLoc, diag::err_sizeof_alignof_bitfield) << 1 << ExprRange; 1689 return true; 1690 } 1691 1692 // Alignment of a field access is always okay, so long as it isn't a 1693 // bit-field. 1694 if (MemberExpr *ME = dyn_cast<MemberExpr>(E)) 1695 if (isa<FieldDecl>(ME->getMemberDecl())) 1696 return false; 1697 1698 return CheckSizeOfAlignOfOperand(E->getType(), OpLoc, ExprRange, false); 1699} 1700 1701/// \brief Build a sizeof or alignof expression given a type operand. 1702Action::OwningExprResult 1703Sema::CreateSizeOfAlignOfExpr(DeclaratorInfo *DInfo, 1704 SourceLocation OpLoc, 1705 bool isSizeOf, SourceRange R) { 1706 if (!DInfo) 1707 return ExprError(); 1708 1709 QualType T = DInfo->getType(); 1710 1711 if (!T->isDependentType() && 1712 CheckSizeOfAlignOfOperand(T, OpLoc, R, isSizeOf)) 1713 return ExprError(); 1714 1715 // C99 6.5.3.4p4: the type (an unsigned integer type) is size_t. 1716 return Owned(new (Context) SizeOfAlignOfExpr(isSizeOf, DInfo, 1717 Context.getSizeType(), OpLoc, 1718 R.getEnd())); 1719} 1720 1721/// \brief Build a sizeof or alignof expression given an expression 1722/// operand. 1723Action::OwningExprResult 1724Sema::CreateSizeOfAlignOfExpr(Expr *E, SourceLocation OpLoc, 1725 bool isSizeOf, SourceRange R) { 1726 // Verify that the operand is valid. 1727 bool isInvalid = false; 1728 if (E->isTypeDependent()) { 1729 // Delay type-checking for type-dependent expressions. 1730 } else if (!isSizeOf) { 1731 isInvalid = CheckAlignOfExpr(E, OpLoc, R); 1732 } else if (E->getBitField()) { // C99 6.5.3.4p1. 1733 Diag(OpLoc, diag::err_sizeof_alignof_bitfield) << 0; 1734 isInvalid = true; 1735 } else { 1736 isInvalid = CheckSizeOfAlignOfOperand(E->getType(), OpLoc, R, true); 1737 } 1738 1739 if (isInvalid) 1740 return ExprError(); 1741 1742 // C99 6.5.3.4p4: the type (an unsigned integer type) is size_t. 1743 return Owned(new (Context) SizeOfAlignOfExpr(isSizeOf, E, 1744 Context.getSizeType(), OpLoc, 1745 R.getEnd())); 1746} 1747 1748/// ActOnSizeOfAlignOfExpr - Handle @c sizeof(type) and @c sizeof @c expr and 1749/// the same for @c alignof and @c __alignof 1750/// Note that the ArgRange is invalid if isType is false. 1751Action::OwningExprResult 1752Sema::ActOnSizeOfAlignOfExpr(SourceLocation OpLoc, bool isSizeof, bool isType, 1753 void *TyOrEx, const SourceRange &ArgRange) { 1754 // If error parsing type, ignore. 1755 if (TyOrEx == 0) return ExprError(); 1756 1757 if (isType) { 1758 DeclaratorInfo *DInfo; 1759 (void) GetTypeFromParser(TyOrEx, &DInfo); 1760 return CreateSizeOfAlignOfExpr(DInfo, OpLoc, isSizeof, ArgRange); 1761 } 1762 1763 Expr *ArgEx = (Expr *)TyOrEx; 1764 Action::OwningExprResult Result 1765 = CreateSizeOfAlignOfExpr(ArgEx, OpLoc, isSizeof, ArgEx->getSourceRange()); 1766 1767 if (Result.isInvalid()) 1768 DeleteExpr(ArgEx); 1769 1770 return move(Result); 1771} 1772 1773QualType Sema::CheckRealImagOperand(Expr *&V, SourceLocation Loc, bool isReal) { 1774 if (V->isTypeDependent()) 1775 return Context.DependentTy; 1776 1777 // These operators return the element type of a complex type. 1778 if (const ComplexType *CT = V->getType()->getAs<ComplexType>()) 1779 return CT->getElementType(); 1780 1781 // Otherwise they pass through real integer and floating point types here. 1782 if (V->getType()->isArithmeticType()) 1783 return V->getType(); 1784 1785 // Reject anything else. 1786 Diag(Loc, diag::err_realimag_invalid_type) << V->getType() 1787 << (isReal ? "__real" : "__imag"); 1788 return QualType(); 1789} 1790 1791 1792 1793Action::OwningExprResult 1794Sema::ActOnPostfixUnaryOp(Scope *S, SourceLocation OpLoc, 1795 tok::TokenKind Kind, ExprArg Input) { 1796 UnaryOperator::Opcode Opc; 1797 switch (Kind) { 1798 default: assert(0 && "Unknown unary op!"); 1799 case tok::plusplus: Opc = UnaryOperator::PostInc; break; 1800 case tok::minusminus: Opc = UnaryOperator::PostDec; break; 1801 } 1802 1803 return BuildUnaryOp(S, OpLoc, Opc, move(Input)); 1804} 1805 1806Action::OwningExprResult 1807Sema::ActOnArraySubscriptExpr(Scope *S, ExprArg Base, SourceLocation LLoc, 1808 ExprArg Idx, SourceLocation RLoc) { 1809 // Since this might be a postfix expression, get rid of ParenListExprs. 1810 Base = MaybeConvertParenListExprToParenExpr(S, move(Base)); 1811 1812 Expr *LHSExp = static_cast<Expr*>(Base.get()), 1813 *RHSExp = static_cast<Expr*>(Idx.get()); 1814 1815 if (getLangOptions().CPlusPlus && 1816 (LHSExp->isTypeDependent() || RHSExp->isTypeDependent())) { 1817 Base.release(); 1818 Idx.release(); 1819 return Owned(new (Context) ArraySubscriptExpr(LHSExp, RHSExp, 1820 Context.DependentTy, RLoc)); 1821 } 1822 1823 if (getLangOptions().CPlusPlus && 1824 (LHSExp->getType()->isRecordType() || 1825 LHSExp->getType()->isEnumeralType() || 1826 RHSExp->getType()->isRecordType() || 1827 RHSExp->getType()->isEnumeralType())) { 1828 return CreateOverloadedArraySubscriptExpr(LLoc, RLoc, move(Base),move(Idx)); 1829 } 1830 1831 return CreateBuiltinArraySubscriptExpr(move(Base), LLoc, move(Idx), RLoc); 1832} 1833 1834 1835Action::OwningExprResult 1836Sema::CreateBuiltinArraySubscriptExpr(ExprArg Base, SourceLocation LLoc, 1837 ExprArg Idx, SourceLocation RLoc) { 1838 Expr *LHSExp = static_cast<Expr*>(Base.get()); 1839 Expr *RHSExp = static_cast<Expr*>(Idx.get()); 1840 1841 // Perform default conversions. 1842 DefaultFunctionArrayConversion(LHSExp); 1843 DefaultFunctionArrayConversion(RHSExp); 1844 1845 QualType LHSTy = LHSExp->getType(), RHSTy = RHSExp->getType(); 1846 1847 // C99 6.5.2.1p2: the expression e1[e2] is by definition precisely equivalent 1848 // to the expression *((e1)+(e2)). This means the array "Base" may actually be 1849 // in the subscript position. As a result, we need to derive the array base 1850 // and index from the expression types. 1851 Expr *BaseExpr, *IndexExpr; 1852 QualType ResultType; 1853 if (LHSTy->isDependentType() || RHSTy->isDependentType()) { 1854 BaseExpr = LHSExp; 1855 IndexExpr = RHSExp; 1856 ResultType = Context.DependentTy; 1857 } else if (const PointerType *PTy = LHSTy->getAs<PointerType>()) { 1858 BaseExpr = LHSExp; 1859 IndexExpr = RHSExp; 1860 ResultType = PTy->getPointeeType(); 1861 } else if (const PointerType *PTy = RHSTy->getAs<PointerType>()) { 1862 // Handle the uncommon case of "123[Ptr]". 1863 BaseExpr = RHSExp; 1864 IndexExpr = LHSExp; 1865 ResultType = PTy->getPointeeType(); 1866 } else if (const ObjCObjectPointerType *PTy = 1867 LHSTy->getAs<ObjCObjectPointerType>()) { 1868 BaseExpr = LHSExp; 1869 IndexExpr = RHSExp; 1870 ResultType = PTy->getPointeeType(); 1871 } else if (const ObjCObjectPointerType *PTy = 1872 RHSTy->getAs<ObjCObjectPointerType>()) { 1873 // Handle the uncommon case of "123[Ptr]". 1874 BaseExpr = RHSExp; 1875 IndexExpr = LHSExp; 1876 ResultType = PTy->getPointeeType(); 1877 } else if (const VectorType *VTy = LHSTy->getAs<VectorType>()) { 1878 BaseExpr = LHSExp; // vectors: V[123] 1879 IndexExpr = RHSExp; 1880 1881 // FIXME: need to deal with const... 1882 ResultType = VTy->getElementType(); 1883 } else if (LHSTy->isArrayType()) { 1884 // If we see an array that wasn't promoted by 1885 // DefaultFunctionArrayConversion, it must be an array that 1886 // wasn't promoted because of the C90 rule that doesn't 1887 // allow promoting non-lvalue arrays. Warn, then 1888 // force the promotion here. 1889 Diag(LHSExp->getLocStart(), diag::ext_subscript_non_lvalue) << 1890 LHSExp->getSourceRange(); 1891 ImpCastExprToType(LHSExp, Context.getArrayDecayedType(LHSTy), 1892 CastExpr::CK_ArrayToPointerDecay); 1893 LHSTy = LHSExp->getType(); 1894 1895 BaseExpr = LHSExp; 1896 IndexExpr = RHSExp; 1897 ResultType = LHSTy->getAs<PointerType>()->getPointeeType(); 1898 } else if (RHSTy->isArrayType()) { 1899 // Same as previous, except for 123[f().a] case 1900 Diag(RHSExp->getLocStart(), diag::ext_subscript_non_lvalue) << 1901 RHSExp->getSourceRange(); 1902 ImpCastExprToType(RHSExp, Context.getArrayDecayedType(RHSTy), 1903 CastExpr::CK_ArrayToPointerDecay); 1904 RHSTy = RHSExp->getType(); 1905 1906 BaseExpr = RHSExp; 1907 IndexExpr = LHSExp; 1908 ResultType = RHSTy->getAs<PointerType>()->getPointeeType(); 1909 } else { 1910 return ExprError(Diag(LLoc, diag::err_typecheck_subscript_value) 1911 << LHSExp->getSourceRange() << RHSExp->getSourceRange()); 1912 } 1913 // C99 6.5.2.1p1 1914 if (!(IndexExpr->getType()->isIntegerType() && 1915 IndexExpr->getType()->isScalarType()) && !IndexExpr->isTypeDependent()) 1916 return ExprError(Diag(LLoc, diag::err_typecheck_subscript_not_integer) 1917 << IndexExpr->getSourceRange()); 1918 1919 if ((IndexExpr->getType()->isSpecificBuiltinType(BuiltinType::Char_S) || 1920 IndexExpr->getType()->isSpecificBuiltinType(BuiltinType::Char_U)) 1921 && !IndexExpr->isTypeDependent()) 1922 Diag(LLoc, diag::warn_subscript_is_char) << IndexExpr->getSourceRange(); 1923 1924 // C99 6.5.2.1p1: "shall have type "pointer to *object* type". Similarly, 1925 // C++ [expr.sub]p1: The type "T" shall be a completely-defined object 1926 // type. Note that Functions are not objects, and that (in C99 parlance) 1927 // incomplete types are not object types. 1928 if (ResultType->isFunctionType()) { 1929 Diag(BaseExpr->getLocStart(), diag::err_subscript_function_type) 1930 << ResultType << BaseExpr->getSourceRange(); 1931 return ExprError(); 1932 } 1933 1934 if (!ResultType->isDependentType() && 1935 RequireCompleteType(LLoc, ResultType, 1936 PDiag(diag::err_subscript_incomplete_type) 1937 << BaseExpr->getSourceRange())) 1938 return ExprError(); 1939 1940 // Diagnose bad cases where we step over interface counts. 1941 if (ResultType->isObjCInterfaceType() && LangOpts.ObjCNonFragileABI) { 1942 Diag(LLoc, diag::err_subscript_nonfragile_interface) 1943 << ResultType << BaseExpr->getSourceRange(); 1944 return ExprError(); 1945 } 1946 1947 Base.release(); 1948 Idx.release(); 1949 return Owned(new (Context) ArraySubscriptExpr(LHSExp, RHSExp, 1950 ResultType, RLoc)); 1951} 1952 1953QualType Sema:: 1954CheckExtVectorComponent(QualType baseType, SourceLocation OpLoc, 1955 const IdentifierInfo *CompName, 1956 SourceLocation CompLoc) { 1957 // FIXME: Share logic with ExtVectorElementExpr::containsDuplicateElements, 1958 // see FIXME there. 1959 // 1960 // FIXME: This logic can be greatly simplified by splitting it along 1961 // halving/not halving and reworking the component checking. 1962 const ExtVectorType *vecType = baseType->getAs<ExtVectorType>(); 1963 1964 // The vector accessor can't exceed the number of elements. 1965 const char *compStr = CompName->getNameStart(); 1966 1967 // This flag determines whether or not the component is one of the four 1968 // special names that indicate a subset of exactly half the elements are 1969 // to be selected. 1970 bool HalvingSwizzle = false; 1971 1972 // This flag determines whether or not CompName has an 's' char prefix, 1973 // indicating that it is a string of hex values to be used as vector indices. 1974 bool HexSwizzle = *compStr == 's' || *compStr == 'S'; 1975 1976 // Check that we've found one of the special components, or that the component 1977 // names must come from the same set. 1978 if (!strcmp(compStr, "hi") || !strcmp(compStr, "lo") || 1979 !strcmp(compStr, "even") || !strcmp(compStr, "odd")) { 1980 HalvingSwizzle = true; 1981 } else if (vecType->getPointAccessorIdx(*compStr) != -1) { 1982 do 1983 compStr++; 1984 while (*compStr && vecType->getPointAccessorIdx(*compStr) != -1); 1985 } else if (HexSwizzle || vecType->getNumericAccessorIdx(*compStr) != -1) { 1986 do 1987 compStr++; 1988 while (*compStr && vecType->getNumericAccessorIdx(*compStr) != -1); 1989 } 1990 1991 if (!HalvingSwizzle && *compStr) { 1992 // We didn't get to the end of the string. This means the component names 1993 // didn't come from the same set *or* we encountered an illegal name. 1994 Diag(OpLoc, diag::err_ext_vector_component_name_illegal) 1995 << std::string(compStr,compStr+1) << SourceRange(CompLoc); 1996 return QualType(); 1997 } 1998 1999 // Ensure no component accessor exceeds the width of the vector type it 2000 // operates on. 2001 if (!HalvingSwizzle) { 2002 compStr = CompName->getNameStart(); 2003 2004 if (HexSwizzle) 2005 compStr++; 2006 2007 while (*compStr) { 2008 if (!vecType->isAccessorWithinNumElements(*compStr++)) { 2009 Diag(OpLoc, diag::err_ext_vector_component_exceeds_length) 2010 << baseType << SourceRange(CompLoc); 2011 return QualType(); 2012 } 2013 } 2014 } 2015 2016 // If this is a halving swizzle, verify that the base type has an even 2017 // number of elements. 2018 if (HalvingSwizzle && (vecType->getNumElements() & 1U)) { 2019 Diag(OpLoc, diag::err_ext_vector_component_requires_even) 2020 << baseType << SourceRange(CompLoc); 2021 return QualType(); 2022 } 2023 2024 // The component accessor looks fine - now we need to compute the actual type. 2025 // The vector type is implied by the component accessor. For example, 2026 // vec4.b is a float, vec4.xy is a vec2, vec4.rgb is a vec3, etc. 2027 // vec4.s0 is a float, vec4.s23 is a vec3, etc. 2028 // vec4.hi, vec4.lo, vec4.e, and vec4.o all return vec2. 2029 unsigned CompSize = HalvingSwizzle ? vecType->getNumElements() / 2 2030 : CompName->getLength(); 2031 if (HexSwizzle) 2032 CompSize--; 2033 2034 if (CompSize == 1) 2035 return vecType->getElementType(); 2036 2037 QualType VT = Context.getExtVectorType(vecType->getElementType(), CompSize); 2038 // Now look up the TypeDefDecl from the vector type. Without this, 2039 // diagostics look bad. We want extended vector types to appear built-in. 2040 for (unsigned i = 0, E = ExtVectorDecls.size(); i != E; ++i) { 2041 if (ExtVectorDecls[i]->getUnderlyingType() == VT) 2042 return Context.getTypedefType(ExtVectorDecls[i]); 2043 } 2044 return VT; // should never get here (a typedef type should always be found). 2045} 2046 2047static Decl *FindGetterNameDeclFromProtocolList(const ObjCProtocolDecl*PDecl, 2048 IdentifierInfo *Member, 2049 const Selector &Sel, 2050 ASTContext &Context) { 2051 2052 if (ObjCPropertyDecl *PD = PDecl->FindPropertyDeclaration(Member)) 2053 return PD; 2054 if (ObjCMethodDecl *OMD = PDecl->getInstanceMethod(Sel)) 2055 return OMD; 2056 2057 for (ObjCProtocolDecl::protocol_iterator I = PDecl->protocol_begin(), 2058 E = PDecl->protocol_end(); I != E; ++I) { 2059 if (Decl *D = FindGetterNameDeclFromProtocolList(*I, Member, Sel, 2060 Context)) 2061 return D; 2062 } 2063 return 0; 2064} 2065 2066static Decl *FindGetterNameDecl(const ObjCObjectPointerType *QIdTy, 2067 IdentifierInfo *Member, 2068 const Selector &Sel, 2069 ASTContext &Context) { 2070 // Check protocols on qualified interfaces. 2071 Decl *GDecl = 0; 2072 for (ObjCObjectPointerType::qual_iterator I = QIdTy->qual_begin(), 2073 E = QIdTy->qual_end(); I != E; ++I) { 2074 if (ObjCPropertyDecl *PD = (*I)->FindPropertyDeclaration(Member)) { 2075 GDecl = PD; 2076 break; 2077 } 2078 // Also must look for a getter name which uses property syntax. 2079 if (ObjCMethodDecl *OMD = (*I)->getInstanceMethod(Sel)) { 2080 GDecl = OMD; 2081 break; 2082 } 2083 } 2084 if (!GDecl) { 2085 for (ObjCObjectPointerType::qual_iterator I = QIdTy->qual_begin(), 2086 E = QIdTy->qual_end(); I != E; ++I) { 2087 // Search in the protocol-qualifier list of current protocol. 2088 GDecl = FindGetterNameDeclFromProtocolList(*I, Member, Sel, Context); 2089 if (GDecl) 2090 return GDecl; 2091 } 2092 } 2093 return GDecl; 2094} 2095 2096Sema::OwningExprResult 2097Sema::ActOnDependentMemberExpr(ExprArg Base, QualType BaseType, 2098 bool IsArrow, SourceLocation OpLoc, 2099 const CXXScopeSpec &SS, 2100 NamedDecl *FirstQualifierInScope, 2101 DeclarationName Name, SourceLocation NameLoc, 2102 const TemplateArgumentListInfo *TemplateArgs) { 2103 Expr *BaseExpr = Base.takeAs<Expr>(); 2104 2105 // Even in dependent contexts, try to diagnose base expressions with 2106 // obviously wrong types, e.g.: 2107 // 2108 // T* t; 2109 // t.f; 2110 // 2111 // In Obj-C++, however, the above expression is valid, since it could be 2112 // accessing the 'f' property if T is an Obj-C interface. The extra check 2113 // allows this, while still reporting an error if T is a struct pointer. 2114 if (!IsArrow) { 2115 const PointerType *PT = BaseType->getAs<PointerType>(); 2116 if (PT && (!getLangOptions().ObjC1 || 2117 PT->getPointeeType()->isRecordType())) { 2118 assert(BaseExpr && "cannot happen with implicit member accesses"); 2119 Diag(NameLoc, diag::err_typecheck_member_reference_struct_union) 2120 << BaseType << BaseExpr->getSourceRange(); 2121 return ExprError(); 2122 } 2123 } 2124 2125 assert(BaseType->isDependentType()); 2126 2127 // Get the type being accessed in BaseType. If this is an arrow, the BaseExpr 2128 // must have pointer type, and the accessed type is the pointee. 2129 return Owned(CXXDependentScopeMemberExpr::Create(Context, BaseExpr, BaseType, 2130 IsArrow, OpLoc, 2131 static_cast<NestedNameSpecifier*>(SS.getScopeRep()), 2132 SS.getRange(), 2133 FirstQualifierInScope, 2134 Name, NameLoc, 2135 TemplateArgs)); 2136} 2137 2138/// We know that the given qualified member reference points only to 2139/// declarations which do not belong to the static type of the base 2140/// expression. Diagnose the problem. 2141static void DiagnoseQualifiedMemberReference(Sema &SemaRef, 2142 Expr *BaseExpr, 2143 QualType BaseType, 2144 const CXXScopeSpec &SS, 2145 const LookupResult &R) { 2146 // If this is an implicit member access, use a different set of 2147 // diagnostics. 2148 if (!BaseExpr) 2149 return DiagnoseInstanceReference(SemaRef, SS, R); 2150 2151 // FIXME: this is an exceedingly lame diagnostic for some of the more 2152 // complicated cases here. 2153 DeclContext *DC = R.getRepresentativeDecl()->getDeclContext(); 2154 SemaRef.Diag(R.getNameLoc(), diag::err_not_direct_base_or_virtual) 2155 << SS.getRange() << DC << BaseType; 2156} 2157 2158// Check whether the declarations we found through a nested-name 2159// specifier in a member expression are actually members of the base 2160// type. The restriction here is: 2161// 2162// C++ [expr.ref]p2: 2163// ... In these cases, the id-expression shall name a 2164// member of the class or of one of its base classes. 2165// 2166// So it's perfectly legitimate for the nested-name specifier to name 2167// an unrelated class, and for us to find an overload set including 2168// decls from classes which are not superclasses, as long as the decl 2169// we actually pick through overload resolution is from a superclass. 2170bool Sema::CheckQualifiedMemberReference(Expr *BaseExpr, 2171 QualType BaseType, 2172 const CXXScopeSpec &SS, 2173 const LookupResult &R) { 2174 const RecordType *BaseRT = BaseType->getAs<RecordType>(); 2175 if (!BaseRT) { 2176 // We can't check this yet because the base type is still 2177 // dependent. 2178 assert(BaseType->isDependentType()); 2179 return false; 2180 } 2181 CXXRecordDecl *BaseRecord = cast<CXXRecordDecl>(BaseRT->getDecl()); 2182 2183 for (LookupResult::iterator I = R.begin(), E = R.end(); I != E; ++I) { 2184 // If this is an implicit member reference and we find a 2185 // non-instance member, it's not an error. 2186 if (!BaseExpr && !IsInstanceMember((*I)->getUnderlyingDecl())) 2187 return false; 2188 2189 // Note that we use the DC of the decl, not the underlying decl. 2190 CXXRecordDecl *RecordD = cast<CXXRecordDecl>((*I)->getDeclContext()); 2191 while (RecordD->isAnonymousStructOrUnion()) 2192 RecordD = cast<CXXRecordDecl>(RecordD->getParent()); 2193 2194 llvm::SmallPtrSet<CXXRecordDecl*,4> MemberRecord; 2195 MemberRecord.insert(RecordD->getCanonicalDecl()); 2196 2197 if (!IsProvablyNotDerivedFrom(*this, BaseRecord, MemberRecord)) 2198 return false; 2199 } 2200 2201 DiagnoseQualifiedMemberReference(*this, BaseExpr, BaseType, SS, R); 2202 return true; 2203} 2204 2205static bool 2206LookupMemberExprInRecord(Sema &SemaRef, LookupResult &R, 2207 SourceRange BaseRange, const RecordType *RTy, 2208 SourceLocation OpLoc, const CXXScopeSpec &SS) { 2209 RecordDecl *RDecl = RTy->getDecl(); 2210 if (SemaRef.RequireCompleteType(OpLoc, QualType(RTy, 0), 2211 PDiag(diag::err_typecheck_incomplete_tag) 2212 << BaseRange)) 2213 return true; 2214 2215 DeclContext *DC = RDecl; 2216 if (SS.isSet()) { 2217 // If the member name was a qualified-id, look into the 2218 // nested-name-specifier. 2219 DC = SemaRef.computeDeclContext(SS, false); 2220 2221 if (SemaRef.RequireCompleteDeclContext(SS)) { 2222 SemaRef.Diag(SS.getRange().getEnd(), diag::err_typecheck_incomplete_tag) 2223 << SS.getRange() << DC; 2224 return true; 2225 } 2226 2227 assert(DC && "Cannot handle non-computable dependent contexts in lookup"); 2228 2229 if (!isa<TypeDecl>(DC)) { 2230 SemaRef.Diag(R.getNameLoc(), diag::err_qualified_member_nonclass) 2231 << DC << SS.getRange(); 2232 return true; 2233 } 2234 } 2235 2236 // The record definition is complete, now look up the member. 2237 SemaRef.LookupQualifiedName(R, DC); 2238 2239 return false; 2240} 2241 2242Sema::OwningExprResult 2243Sema::BuildMemberReferenceExpr(ExprArg BaseArg, QualType BaseType, 2244 SourceLocation OpLoc, bool IsArrow, 2245 const CXXScopeSpec &SS, 2246 NamedDecl *FirstQualifierInScope, 2247 DeclarationName Name, SourceLocation NameLoc, 2248 const TemplateArgumentListInfo *TemplateArgs) { 2249 Expr *Base = BaseArg.takeAs<Expr>(); 2250 2251 if (BaseType->isDependentType() || 2252 (SS.isSet() && isDependentScopeSpecifier(SS))) 2253 return ActOnDependentMemberExpr(ExprArg(*this, Base), BaseType, 2254 IsArrow, OpLoc, 2255 SS, FirstQualifierInScope, 2256 Name, NameLoc, 2257 TemplateArgs); 2258 2259 LookupResult R(*this, Name, NameLoc, LookupMemberName); 2260 2261 // Implicit member accesses. 2262 if (!Base) { 2263 QualType RecordTy = BaseType; 2264 if (IsArrow) RecordTy = RecordTy->getAs<PointerType>()->getPointeeType(); 2265 if (LookupMemberExprInRecord(*this, R, SourceRange(), 2266 RecordTy->getAs<RecordType>(), 2267 OpLoc, SS)) 2268 return ExprError(); 2269 2270 // Explicit member accesses. 2271 } else { 2272 OwningExprResult Result = 2273 LookupMemberExpr(R, Base, IsArrow, OpLoc, 2274 SS, FirstQualifierInScope, 2275 /*ObjCImpDecl*/ DeclPtrTy()); 2276 2277 if (Result.isInvalid()) { 2278 Owned(Base); 2279 return ExprError(); 2280 } 2281 2282 if (Result.get()) 2283 return move(Result); 2284 } 2285 2286 return BuildMemberReferenceExpr(ExprArg(*this, Base), BaseType, 2287 OpLoc, IsArrow, SS, R, TemplateArgs); 2288} 2289 2290Sema::OwningExprResult 2291Sema::BuildMemberReferenceExpr(ExprArg Base, QualType BaseExprType, 2292 SourceLocation OpLoc, bool IsArrow, 2293 const CXXScopeSpec &SS, 2294 LookupResult &R, 2295 const TemplateArgumentListInfo *TemplateArgs) { 2296 Expr *BaseExpr = Base.takeAs<Expr>(); 2297 QualType BaseType = BaseExprType; 2298 if (IsArrow) { 2299 assert(BaseType->isPointerType()); 2300 BaseType = BaseType->getAs<PointerType>()->getPointeeType(); 2301 } 2302 2303 NestedNameSpecifier *Qualifier = 2304 static_cast<NestedNameSpecifier*>(SS.getScopeRep()); 2305 DeclarationName MemberName = R.getLookupName(); 2306 SourceLocation MemberLoc = R.getNameLoc(); 2307 2308 if (R.isAmbiguous()) 2309 return ExprError(); 2310 2311 if (R.empty()) { 2312 // Rederive where we looked up. 2313 DeclContext *DC = (SS.isSet() 2314 ? computeDeclContext(SS, false) 2315 : BaseType->getAs<RecordType>()->getDecl()); 2316 2317 Diag(R.getNameLoc(), diag::err_no_member) 2318 << MemberName << DC 2319 << (BaseExpr ? BaseExpr->getSourceRange() : SourceRange()); 2320 return ExprError(); 2321 } 2322 2323 // Diagnose qualified lookups that find only declarations from a 2324 // non-base type. Note that it's okay for lookup to find 2325 // declarations from a non-base type as long as those aren't the 2326 // ones picked by overload resolution. 2327 if (SS.isSet() && CheckQualifiedMemberReference(BaseExpr, BaseType, SS, R)) 2328 return ExprError(); 2329 2330 // Construct an unresolved result if we in fact got an unresolved 2331 // result. 2332 if (R.isOverloadedResult() || R.isUnresolvableResult()) { 2333 bool Dependent = 2334 R.isUnresolvableResult() || 2335 UnresolvedLookupExpr::ComputeDependence(R.begin(), R.end(), TemplateArgs); 2336 2337 UnresolvedMemberExpr *MemExpr 2338 = UnresolvedMemberExpr::Create(Context, Dependent, 2339 R.isUnresolvableResult(), 2340 BaseExpr, BaseExprType, 2341 IsArrow, OpLoc, 2342 Qualifier, SS.getRange(), 2343 MemberName, MemberLoc, 2344 TemplateArgs); 2345 for (LookupResult::iterator I = R.begin(), E = R.end(); I != E; ++I) 2346 MemExpr->addDecl(*I); 2347 2348 return Owned(MemExpr); 2349 } 2350 2351 assert(R.isSingleResult()); 2352 NamedDecl *MemberDecl = R.getFoundDecl(); 2353 2354 // FIXME: diagnose the presence of template arguments now. 2355 2356 // If the decl being referenced had an error, return an error for this 2357 // sub-expr without emitting another error, in order to avoid cascading 2358 // error cases. 2359 if (MemberDecl->isInvalidDecl()) 2360 return ExprError(); 2361 2362 // Handle the implicit-member-access case. 2363 if (!BaseExpr) { 2364 // If this is not an instance member, convert to a non-member access. 2365 if (!IsInstanceMember(MemberDecl)) 2366 return BuildDeclarationNameExpr(SS, R.getNameLoc(), MemberDecl); 2367 2368 BaseExpr = new (Context) CXXThisExpr(SourceLocation(), BaseExprType); 2369 } 2370 2371 bool ShouldCheckUse = true; 2372 if (CXXMethodDecl *MD = dyn_cast<CXXMethodDecl>(MemberDecl)) { 2373 // Don't diagnose the use of a virtual member function unless it's 2374 // explicitly qualified. 2375 if (MD->isVirtual() && !SS.isSet()) 2376 ShouldCheckUse = false; 2377 } 2378 2379 // Check the use of this member. 2380 if (ShouldCheckUse && DiagnoseUseOfDecl(MemberDecl, MemberLoc)) { 2381 Owned(BaseExpr); 2382 return ExprError(); 2383 } 2384 2385 if (FieldDecl *FD = dyn_cast<FieldDecl>(MemberDecl)) { 2386 // We may have found a field within an anonymous union or struct 2387 // (C++ [class.union]). 2388 if (cast<RecordDecl>(FD->getDeclContext())->isAnonymousStructOrUnion()) 2389 return BuildAnonymousStructUnionMemberReference(MemberLoc, FD, 2390 BaseExpr, OpLoc); 2391 2392 // Figure out the type of the member; see C99 6.5.2.3p3, C++ [expr.ref] 2393 QualType MemberType = FD->getType(); 2394 if (const ReferenceType *Ref = MemberType->getAs<ReferenceType>()) 2395 MemberType = Ref->getPointeeType(); 2396 else { 2397 Qualifiers BaseQuals = BaseType.getQualifiers(); 2398 BaseQuals.removeObjCGCAttr(); 2399 if (FD->isMutable()) BaseQuals.removeConst(); 2400 2401 Qualifiers MemberQuals 2402 = Context.getCanonicalType(MemberType).getQualifiers(); 2403 2404 Qualifiers Combined = BaseQuals + MemberQuals; 2405 if (Combined != MemberQuals) 2406 MemberType = Context.getQualifiedType(MemberType, Combined); 2407 } 2408 2409 MarkDeclarationReferenced(MemberLoc, FD); 2410 if (PerformObjectMemberConversion(BaseExpr, FD)) 2411 return ExprError(); 2412 return Owned(BuildMemberExpr(Context, BaseExpr, IsArrow, SS, 2413 FD, MemberLoc, MemberType)); 2414 } 2415 2416 if (VarDecl *Var = dyn_cast<VarDecl>(MemberDecl)) { 2417 MarkDeclarationReferenced(MemberLoc, Var); 2418 return Owned(BuildMemberExpr(Context, BaseExpr, IsArrow, SS, 2419 Var, MemberLoc, 2420 Var->getType().getNonReferenceType())); 2421 } 2422 2423 if (FunctionDecl *MemberFn = dyn_cast<FunctionDecl>(MemberDecl)) { 2424 MarkDeclarationReferenced(MemberLoc, MemberDecl); 2425 return Owned(BuildMemberExpr(Context, BaseExpr, IsArrow, SS, 2426 MemberFn, MemberLoc, 2427 MemberFn->getType())); 2428 } 2429 2430 if (EnumConstantDecl *Enum = dyn_cast<EnumConstantDecl>(MemberDecl)) { 2431 MarkDeclarationReferenced(MemberLoc, MemberDecl); 2432 return Owned(BuildMemberExpr(Context, BaseExpr, IsArrow, SS, 2433 Enum, MemberLoc, Enum->getType())); 2434 } 2435 2436 Owned(BaseExpr); 2437 2438 if (isa<TypeDecl>(MemberDecl)) 2439 return ExprError(Diag(MemberLoc,diag::err_typecheck_member_reference_type) 2440 << MemberName << int(IsArrow)); 2441 2442 // We found a declaration kind that we didn't expect. This is a 2443 // generic error message that tells the user that she can't refer 2444 // to this member with '.' or '->'. 2445 return ExprError(Diag(MemberLoc, 2446 diag::err_typecheck_member_reference_unknown) 2447 << MemberName << int(IsArrow)); 2448} 2449 2450/// Look up the given member of the given non-type-dependent 2451/// expression. This can return in one of two ways: 2452/// * If it returns a sentinel null-but-valid result, the caller will 2453/// assume that lookup was performed and the results written into 2454/// the provided structure. It will take over from there. 2455/// * Otherwise, the returned expression will be produced in place of 2456/// an ordinary member expression. 2457/// 2458/// The ObjCImpDecl bit is a gross hack that will need to be properly 2459/// fixed for ObjC++. 2460Sema::OwningExprResult 2461Sema::LookupMemberExpr(LookupResult &R, Expr *&BaseExpr, 2462 bool IsArrow, SourceLocation OpLoc, 2463 const CXXScopeSpec &SS, 2464 NamedDecl *FirstQualifierInScope, 2465 DeclPtrTy ObjCImpDecl) { 2466 assert(BaseExpr && "no base expression"); 2467 2468 // Perform default conversions. 2469 DefaultFunctionArrayConversion(BaseExpr); 2470 2471 QualType BaseType = BaseExpr->getType(); 2472 assert(!BaseType->isDependentType()); 2473 2474 DeclarationName MemberName = R.getLookupName(); 2475 SourceLocation MemberLoc = R.getNameLoc(); 2476 2477 // If the user is trying to apply -> or . to a function pointer 2478 // type, it's probably because they forgot parentheses to call that 2479 // function. Suggest the addition of those parentheses, build the 2480 // call, and continue on. 2481 if (const PointerType *Ptr = BaseType->getAs<PointerType>()) { 2482 if (const FunctionProtoType *Fun 2483 = Ptr->getPointeeType()->getAs<FunctionProtoType>()) { 2484 QualType ResultTy = Fun->getResultType(); 2485 if (Fun->getNumArgs() == 0 && 2486 ((!IsArrow && ResultTy->isRecordType()) || 2487 (IsArrow && ResultTy->isPointerType() && 2488 ResultTy->getAs<PointerType>()->getPointeeType() 2489 ->isRecordType()))) { 2490 SourceLocation Loc = PP.getLocForEndOfToken(BaseExpr->getLocEnd()); 2491 Diag(Loc, diag::err_member_reference_needs_call) 2492 << QualType(Fun, 0) 2493 << CodeModificationHint::CreateInsertion(Loc, "()"); 2494 2495 OwningExprResult NewBase 2496 = ActOnCallExpr(0, ExprArg(*this, BaseExpr), Loc, 2497 MultiExprArg(*this, 0, 0), 0, Loc); 2498 if (NewBase.isInvalid()) 2499 return ExprError(); 2500 2501 BaseExpr = NewBase.takeAs<Expr>(); 2502 DefaultFunctionArrayConversion(BaseExpr); 2503 BaseType = BaseExpr->getType(); 2504 } 2505 } 2506 } 2507 2508 // If this is an Objective-C pseudo-builtin and a definition is provided then 2509 // use that. 2510 if (BaseType->isObjCIdType()) { 2511 // We have an 'id' type. Rather than fall through, we check if this 2512 // is a reference to 'isa'. 2513 if (BaseType != Context.ObjCIdRedefinitionType) { 2514 BaseType = Context.ObjCIdRedefinitionType; 2515 ImpCastExprToType(BaseExpr, BaseType, CastExpr::CK_BitCast); 2516 } 2517 } 2518 2519 // If this is an Objective-C pseudo-builtin and a definition is provided then 2520 // use that. 2521 if (Context.isObjCSelType(BaseType)) { 2522 // We have an 'SEL' type. Rather than fall through, we check if this 2523 // is a reference to 'sel_id'. 2524 if (BaseType != Context.ObjCSelRedefinitionType) { 2525 BaseType = Context.ObjCSelRedefinitionType; 2526 ImpCastExprToType(BaseExpr, BaseType, CastExpr::CK_BitCast); 2527 } 2528 } 2529 2530 assert(!BaseType.isNull() && "no type for member expression"); 2531 2532 // Handle properties on ObjC 'Class' types. 2533 if (!IsArrow && BaseType->isObjCClassType()) { 2534 // Also must look for a getter name which uses property syntax. 2535 IdentifierInfo *Member = MemberName.getAsIdentifierInfo(); 2536 Selector Sel = PP.getSelectorTable().getNullarySelector(Member); 2537 if (ObjCMethodDecl *MD = getCurMethodDecl()) { 2538 ObjCInterfaceDecl *IFace = MD->getClassInterface(); 2539 ObjCMethodDecl *Getter; 2540 // FIXME: need to also look locally in the implementation. 2541 if ((Getter = IFace->lookupClassMethod(Sel))) { 2542 // Check the use of this method. 2543 if (DiagnoseUseOfDecl(Getter, MemberLoc)) 2544 return ExprError(); 2545 } 2546 // If we found a getter then this may be a valid dot-reference, we 2547 // will look for the matching setter, in case it is needed. 2548 Selector SetterSel = 2549 SelectorTable::constructSetterName(PP.getIdentifierTable(), 2550 PP.getSelectorTable(), Member); 2551 ObjCMethodDecl *Setter = IFace->lookupClassMethod(SetterSel); 2552 if (!Setter) { 2553 // If this reference is in an @implementation, also check for 'private' 2554 // methods. 2555 Setter = IFace->lookupPrivateInstanceMethod(SetterSel); 2556 } 2557 // Look through local category implementations associated with the class. 2558 if (!Setter) 2559 Setter = IFace->getCategoryClassMethod(SetterSel); 2560 2561 if (Setter && DiagnoseUseOfDecl(Setter, MemberLoc)) 2562 return ExprError(); 2563 2564 if (Getter || Setter) { 2565 QualType PType; 2566 2567 if (Getter) 2568 PType = Getter->getResultType(); 2569 else 2570 // Get the expression type from Setter's incoming parameter. 2571 PType = (*(Setter->param_end() -1))->getType(); 2572 // FIXME: we must check that the setter has property type. 2573 return Owned(new (Context) ObjCImplicitSetterGetterRefExpr(Getter, 2574 PType, 2575 Setter, MemberLoc, BaseExpr)); 2576 } 2577 return ExprError(Diag(MemberLoc, diag::err_property_not_found) 2578 << MemberName << BaseType); 2579 } 2580 } 2581 2582 if (BaseType->isObjCClassType() && 2583 BaseType != Context.ObjCClassRedefinitionType) { 2584 BaseType = Context.ObjCClassRedefinitionType; 2585 ImpCastExprToType(BaseExpr, BaseType, CastExpr::CK_BitCast); 2586 } 2587 2588 if (IsArrow) { 2589 if (const PointerType *PT = BaseType->getAs<PointerType>()) 2590 BaseType = PT->getPointeeType(); 2591 else if (BaseType->isObjCObjectPointerType()) 2592 ; 2593 else { 2594 Diag(MemberLoc, diag::err_typecheck_member_reference_arrow) 2595 << BaseType << BaseExpr->getSourceRange(); 2596 return ExprError(); 2597 } 2598 } 2599 2600 // Handle field access to simple records. This also handles access 2601 // to fields of the ObjC 'id' struct. 2602 if (const RecordType *RTy = BaseType->getAs<RecordType>()) { 2603 if (LookupMemberExprInRecord(*this, R, BaseExpr->getSourceRange(), 2604 RTy, OpLoc, SS)) 2605 return ExprError(); 2606 return Owned((Expr*) 0); 2607 } 2608 2609 // Handle pseudo-destructors (C++ [expr.pseudo]). Since anything referring 2610 // into a record type was handled above, any destructor we see here is a 2611 // pseudo-destructor. 2612 if (MemberName.getNameKind() == DeclarationName::CXXDestructorName) { 2613 // C++ [expr.pseudo]p2: 2614 // The left hand side of the dot operator shall be of scalar type. The 2615 // left hand side of the arrow operator shall be of pointer to scalar 2616 // type. 2617 if (!BaseType->isScalarType()) 2618 return Owned(Diag(OpLoc, diag::err_pseudo_dtor_base_not_scalar) 2619 << BaseType << BaseExpr->getSourceRange()); 2620 2621 // [...] The type designated by the pseudo-destructor-name shall be the 2622 // same as the object type. 2623 if (!MemberName.getCXXNameType()->isDependentType() && 2624 !Context.hasSameUnqualifiedType(BaseType, MemberName.getCXXNameType())) 2625 return Owned(Diag(OpLoc, diag::err_pseudo_dtor_type_mismatch) 2626 << BaseType << MemberName.getCXXNameType() 2627 << BaseExpr->getSourceRange() << SourceRange(MemberLoc)); 2628 2629 // [...] Furthermore, the two type-names in a pseudo-destructor-name of 2630 // the form 2631 // 2632 // ::[opt] nested-name-specifier[opt] type-name :: ̃ type-name 2633 // 2634 // shall designate the same scalar type. 2635 // 2636 // FIXME: DPG can't see any way to trigger this particular clause, so it 2637 // isn't checked here. 2638 2639 // FIXME: We've lost the precise spelling of the type by going through 2640 // DeclarationName. Can we do better? 2641 return Owned(new (Context) CXXPseudoDestructorExpr(Context, BaseExpr, 2642 IsArrow, OpLoc, 2643 (NestedNameSpecifier *) SS.getScopeRep(), 2644 SS.getRange(), 2645 MemberName.getCXXNameType(), 2646 MemberLoc)); 2647 } 2648 2649 // Handle access to Objective-C instance variables, such as "Obj->ivar" and 2650 // (*Obj).ivar. 2651 if ((IsArrow && BaseType->isObjCObjectPointerType()) || 2652 (!IsArrow && BaseType->isObjCInterfaceType())) { 2653 const ObjCObjectPointerType *OPT = BaseType->getAs<ObjCObjectPointerType>(); 2654 const ObjCInterfaceType *IFaceT = 2655 OPT ? OPT->getInterfaceType() : BaseType->getAs<ObjCInterfaceType>(); 2656 if (IFaceT) { 2657 IdentifierInfo *Member = MemberName.getAsIdentifierInfo(); 2658 2659 ObjCInterfaceDecl *IDecl = IFaceT->getDecl(); 2660 ObjCInterfaceDecl *ClassDeclared; 2661 ObjCIvarDecl *IV = IDecl->lookupInstanceVariable(Member, ClassDeclared); 2662 2663 if (IV) { 2664 // If the decl being referenced had an error, return an error for this 2665 // sub-expr without emitting another error, in order to avoid cascading 2666 // error cases. 2667 if (IV->isInvalidDecl()) 2668 return ExprError(); 2669 2670 // Check whether we can reference this field. 2671 if (DiagnoseUseOfDecl(IV, MemberLoc)) 2672 return ExprError(); 2673 if (IV->getAccessControl() != ObjCIvarDecl::Public && 2674 IV->getAccessControl() != ObjCIvarDecl::Package) { 2675 ObjCInterfaceDecl *ClassOfMethodDecl = 0; 2676 if (ObjCMethodDecl *MD = getCurMethodDecl()) 2677 ClassOfMethodDecl = MD->getClassInterface(); 2678 else if (ObjCImpDecl && getCurFunctionDecl()) { 2679 // Case of a c-function declared inside an objc implementation. 2680 // FIXME: For a c-style function nested inside an objc implementation 2681 // class, there is no implementation context available, so we pass 2682 // down the context as argument to this routine. Ideally, this context 2683 // need be passed down in the AST node and somehow calculated from the 2684 // AST for a function decl. 2685 Decl *ImplDecl = ObjCImpDecl.getAs<Decl>(); 2686 if (ObjCImplementationDecl *IMPD = 2687 dyn_cast<ObjCImplementationDecl>(ImplDecl)) 2688 ClassOfMethodDecl = IMPD->getClassInterface(); 2689 else if (ObjCCategoryImplDecl* CatImplClass = 2690 dyn_cast<ObjCCategoryImplDecl>(ImplDecl)) 2691 ClassOfMethodDecl = CatImplClass->getClassInterface(); 2692 } 2693 2694 if (IV->getAccessControl() == ObjCIvarDecl::Private) { 2695 if (ClassDeclared != IDecl || 2696 ClassOfMethodDecl != ClassDeclared) 2697 Diag(MemberLoc, diag::error_private_ivar_access) 2698 << IV->getDeclName(); 2699 } else if (!IDecl->isSuperClassOf(ClassOfMethodDecl)) 2700 // @protected 2701 Diag(MemberLoc, diag::error_protected_ivar_access) 2702 << IV->getDeclName(); 2703 } 2704 2705 return Owned(new (Context) ObjCIvarRefExpr(IV, IV->getType(), 2706 MemberLoc, BaseExpr, 2707 IsArrow)); 2708 } 2709 return ExprError(Diag(MemberLoc, diag::err_typecheck_member_reference_ivar) 2710 << IDecl->getDeclName() << MemberName 2711 << BaseExpr->getSourceRange()); 2712 } 2713 } 2714 // Handle properties on 'id' and qualified "id". 2715 if (!IsArrow && (BaseType->isObjCIdType() || 2716 BaseType->isObjCQualifiedIdType())) { 2717 const ObjCObjectPointerType *QIdTy = BaseType->getAs<ObjCObjectPointerType>(); 2718 IdentifierInfo *Member = MemberName.getAsIdentifierInfo(); 2719 2720 // Check protocols on qualified interfaces. 2721 Selector Sel = PP.getSelectorTable().getNullarySelector(Member); 2722 if (Decl *PMDecl = FindGetterNameDecl(QIdTy, Member, Sel, Context)) { 2723 if (ObjCPropertyDecl *PD = dyn_cast<ObjCPropertyDecl>(PMDecl)) { 2724 // Check the use of this declaration 2725 if (DiagnoseUseOfDecl(PD, MemberLoc)) 2726 return ExprError(); 2727 2728 return Owned(new (Context) ObjCPropertyRefExpr(PD, PD->getType(), 2729 MemberLoc, BaseExpr)); 2730 } 2731 if (ObjCMethodDecl *OMD = dyn_cast<ObjCMethodDecl>(PMDecl)) { 2732 // Check the use of this method. 2733 if (DiagnoseUseOfDecl(OMD, MemberLoc)) 2734 return ExprError(); 2735 2736 return Owned(new (Context) ObjCMessageExpr(BaseExpr, Sel, 2737 OMD->getResultType(), 2738 OMD, OpLoc, MemberLoc, 2739 NULL, 0)); 2740 } 2741 } 2742 2743 return ExprError(Diag(MemberLoc, diag::err_property_not_found) 2744 << MemberName << BaseType); 2745 } 2746 // Handle Objective-C property access, which is "Obj.property" where Obj is a 2747 // pointer to a (potentially qualified) interface type. 2748 const ObjCObjectPointerType *OPT; 2749 if (!IsArrow && (OPT = BaseType->getAsObjCInterfacePointerType())) { 2750 const ObjCInterfaceType *IFaceT = OPT->getInterfaceType(); 2751 ObjCInterfaceDecl *IFace = IFaceT->getDecl(); 2752 IdentifierInfo *Member = MemberName.getAsIdentifierInfo(); 2753 2754 // Search for a declared property first. 2755 if (ObjCPropertyDecl *PD = IFace->FindPropertyDeclaration(Member)) { 2756 // Check whether we can reference this property. 2757 if (DiagnoseUseOfDecl(PD, MemberLoc)) 2758 return ExprError(); 2759 QualType ResTy = PD->getType(); 2760 Selector Sel = PP.getSelectorTable().getNullarySelector(Member); 2761 ObjCMethodDecl *Getter = IFace->lookupInstanceMethod(Sel); 2762 if (DiagnosePropertyAccessorMismatch(PD, Getter, MemberLoc)) 2763 ResTy = Getter->getResultType(); 2764 return Owned(new (Context) ObjCPropertyRefExpr(PD, ResTy, 2765 MemberLoc, BaseExpr)); 2766 } 2767 // Check protocols on qualified interfaces. 2768 for (ObjCObjectPointerType::qual_iterator I = OPT->qual_begin(), 2769 E = OPT->qual_end(); I != E; ++I) 2770 if (ObjCPropertyDecl *PD = (*I)->FindPropertyDeclaration(Member)) { 2771 // Check whether we can reference this property. 2772 if (DiagnoseUseOfDecl(PD, MemberLoc)) 2773 return ExprError(); 2774 2775 return Owned(new (Context) ObjCPropertyRefExpr(PD, PD->getType(), 2776 MemberLoc, BaseExpr)); 2777 } 2778 // If that failed, look for an "implicit" property by seeing if the nullary 2779 // selector is implemented. 2780 2781 // FIXME: The logic for looking up nullary and unary selectors should be 2782 // shared with the code in ActOnInstanceMessage. 2783 2784 Selector Sel = PP.getSelectorTable().getNullarySelector(Member); 2785 ObjCMethodDecl *Getter = IFace->lookupInstanceMethod(Sel); 2786 2787 // If this reference is in an @implementation, check for 'private' methods. 2788 if (!Getter) 2789 Getter = IFace->lookupPrivateInstanceMethod(Sel); 2790 2791 // Look through local category implementations associated with the class. 2792 if (!Getter) 2793 Getter = IFace->getCategoryInstanceMethod(Sel); 2794 if (Getter) { 2795 // Check if we can reference this property. 2796 if (DiagnoseUseOfDecl(Getter, MemberLoc)) 2797 return ExprError(); 2798 } 2799 // If we found a getter then this may be a valid dot-reference, we 2800 // will look for the matching setter, in case it is needed. 2801 Selector SetterSel = 2802 SelectorTable::constructSetterName(PP.getIdentifierTable(), 2803 PP.getSelectorTable(), Member); 2804 ObjCMethodDecl *Setter = IFace->lookupInstanceMethod(SetterSel); 2805 if (!Setter) { 2806 // If this reference is in an @implementation, also check for 'private' 2807 // methods. 2808 Setter = IFace->lookupPrivateInstanceMethod(SetterSel); 2809 } 2810 // Look through local category implementations associated with the class. 2811 if (!Setter) 2812 Setter = IFace->getCategoryInstanceMethod(SetterSel); 2813 2814 if (Setter && DiagnoseUseOfDecl(Setter, MemberLoc)) 2815 return ExprError(); 2816 2817 if (Getter || Setter) { 2818 QualType PType; 2819 2820 if (Getter) 2821 PType = Getter->getResultType(); 2822 else 2823 // Get the expression type from Setter's incoming parameter. 2824 PType = (*(Setter->param_end() -1))->getType(); 2825 // FIXME: we must check that the setter has property type. 2826 return Owned(new (Context) ObjCImplicitSetterGetterRefExpr(Getter, PType, 2827 Setter, MemberLoc, BaseExpr)); 2828 } 2829 return ExprError(Diag(MemberLoc, diag::err_property_not_found) 2830 << MemberName << BaseType); 2831 } 2832 2833 // Handle the following exceptional case (*Obj).isa. 2834 if (!IsArrow && 2835 BaseType->isSpecificBuiltinType(BuiltinType::ObjCId) && 2836 MemberName.getAsIdentifierInfo()->isStr("isa")) 2837 return Owned(new (Context) ObjCIsaExpr(BaseExpr, false, MemberLoc, 2838 Context.getObjCIdType())); 2839 2840 // Handle 'field access' to vectors, such as 'V.xx'. 2841 if (BaseType->isExtVectorType()) { 2842 IdentifierInfo *Member = MemberName.getAsIdentifierInfo(); 2843 QualType ret = CheckExtVectorComponent(BaseType, OpLoc, Member, MemberLoc); 2844 if (ret.isNull()) 2845 return ExprError(); 2846 return Owned(new (Context) ExtVectorElementExpr(ret, BaseExpr, *Member, 2847 MemberLoc)); 2848 } 2849 2850 Diag(MemberLoc, diag::err_typecheck_member_reference_struct_union) 2851 << BaseType << BaseExpr->getSourceRange(); 2852 2853 return ExprError(); 2854} 2855 2856static Sema::OwningExprResult DiagnoseDtorReference(Sema &SemaRef, 2857 SourceLocation NameLoc, 2858 Sema::ExprArg MemExpr) { 2859 Expr *E = (Expr *) MemExpr.get(); 2860 SourceLocation ExpectedLParenLoc = SemaRef.PP.getLocForEndOfToken(NameLoc); 2861 SemaRef.Diag(E->getLocStart(), diag::err_dtor_expr_without_call) 2862 << isa<CXXPseudoDestructorExpr>(E) 2863 << CodeModificationHint::CreateInsertion(ExpectedLParenLoc, "()"); 2864 2865 return SemaRef.ActOnCallExpr(/*Scope*/ 0, 2866 move(MemExpr), 2867 /*LPLoc*/ ExpectedLParenLoc, 2868 Sema::MultiExprArg(SemaRef, 0, 0), 2869 /*CommaLocs*/ 0, 2870 /*RPLoc*/ ExpectedLParenLoc); 2871} 2872 2873/// The main callback when the parser finds something like 2874/// expression . [nested-name-specifier] identifier 2875/// expression -> [nested-name-specifier] identifier 2876/// where 'identifier' encompasses a fairly broad spectrum of 2877/// possibilities, including destructor and operator references. 2878/// 2879/// \param OpKind either tok::arrow or tok::period 2880/// \param HasTrailingLParen whether the next token is '(', which 2881/// is used to diagnose mis-uses of special members that can 2882/// only be called 2883/// \param ObjCImpDecl the current ObjC @implementation decl; 2884/// this is an ugly hack around the fact that ObjC @implementations 2885/// aren't properly put in the context chain 2886Sema::OwningExprResult Sema::ActOnMemberAccessExpr(Scope *S, ExprArg BaseArg, 2887 SourceLocation OpLoc, 2888 tok::TokenKind OpKind, 2889 const CXXScopeSpec &SS, 2890 UnqualifiedId &Id, 2891 DeclPtrTy ObjCImpDecl, 2892 bool HasTrailingLParen) { 2893 if (SS.isSet() && SS.isInvalid()) 2894 return ExprError(); 2895 2896 TemplateArgumentListInfo TemplateArgsBuffer; 2897 2898 // Decompose the name into its component parts. 2899 DeclarationName Name; 2900 SourceLocation NameLoc; 2901 const TemplateArgumentListInfo *TemplateArgs; 2902 DecomposeUnqualifiedId(*this, Id, TemplateArgsBuffer, 2903 Name, NameLoc, TemplateArgs); 2904 2905 bool IsArrow = (OpKind == tok::arrow); 2906 2907 NamedDecl *FirstQualifierInScope 2908 = (!SS.isSet() ? 0 : FindFirstQualifierInScope(S, 2909 static_cast<NestedNameSpecifier*>(SS.getScopeRep()))); 2910 2911 // This is a postfix expression, so get rid of ParenListExprs. 2912 BaseArg = MaybeConvertParenListExprToParenExpr(S, move(BaseArg)); 2913 2914 Expr *Base = BaseArg.takeAs<Expr>(); 2915 OwningExprResult Result(*this); 2916 if (Base->getType()->isDependentType()) { 2917 Result = ActOnDependentMemberExpr(ExprArg(*this, Base), Base->getType(), 2918 IsArrow, OpLoc, 2919 SS, FirstQualifierInScope, 2920 Name, NameLoc, 2921 TemplateArgs); 2922 } else { 2923 LookupResult R(*this, Name, NameLoc, LookupMemberName); 2924 if (TemplateArgs) { 2925 // Re-use the lookup done for the template name. 2926 DecomposeTemplateName(R, Id); 2927 } else { 2928 Result = LookupMemberExpr(R, Base, IsArrow, OpLoc, 2929 SS, FirstQualifierInScope, 2930 ObjCImpDecl); 2931 2932 if (Result.isInvalid()) { 2933 Owned(Base); 2934 return ExprError(); 2935 } 2936 2937 if (Result.get()) { 2938 // The only way a reference to a destructor can be used is to 2939 // immediately call it, which falls into this case. If the 2940 // next token is not a '(', produce a diagnostic and build the 2941 // call now. 2942 if (!HasTrailingLParen && 2943 Id.getKind() == UnqualifiedId::IK_DestructorName) 2944 return DiagnoseDtorReference(*this, NameLoc, move(Result)); 2945 2946 return move(Result); 2947 } 2948 } 2949 2950 Result = BuildMemberReferenceExpr(ExprArg(*this, Base), Base->getType(), 2951 OpLoc, IsArrow, SS, R, TemplateArgs); 2952 } 2953 2954 return move(Result); 2955} 2956 2957Sema::OwningExprResult Sema::BuildCXXDefaultArgExpr(SourceLocation CallLoc, 2958 FunctionDecl *FD, 2959 ParmVarDecl *Param) { 2960 if (Param->hasUnparsedDefaultArg()) { 2961 Diag (CallLoc, 2962 diag::err_use_of_default_argument_to_function_declared_later) << 2963 FD << cast<CXXRecordDecl>(FD->getDeclContext())->getDeclName(); 2964 Diag(UnparsedDefaultArgLocs[Param], 2965 diag::note_default_argument_declared_here); 2966 } else { 2967 if (Param->hasUninstantiatedDefaultArg()) { 2968 Expr *UninstExpr = Param->getUninstantiatedDefaultArg(); 2969 2970 // Instantiate the expression. 2971 MultiLevelTemplateArgumentList ArgList = getTemplateInstantiationArgs(FD); 2972 2973 InstantiatingTemplate Inst(*this, CallLoc, Param, 2974 ArgList.getInnermost().getFlatArgumentList(), 2975 ArgList.getInnermost().flat_size()); 2976 2977 OwningExprResult Result = SubstExpr(UninstExpr, ArgList); 2978 if (Result.isInvalid()) 2979 return ExprError(); 2980 2981 if (SetParamDefaultArgument(Param, move(Result), 2982 /*FIXME:EqualLoc*/ 2983 UninstExpr->getSourceRange().getBegin())) 2984 return ExprError(); 2985 } 2986 2987 Expr *DefaultExpr = Param->getDefaultArg(); 2988 2989 // If the default expression creates temporaries, we need to 2990 // push them to the current stack of expression temporaries so they'll 2991 // be properly destroyed. 2992 if (CXXExprWithTemporaries *E 2993 = dyn_cast_or_null<CXXExprWithTemporaries>(DefaultExpr)) { 2994 assert(!E->shouldDestroyTemporaries() && 2995 "Can't destroy temporaries in a default argument expr!"); 2996 for (unsigned I = 0, N = E->getNumTemporaries(); I != N; ++I) 2997 ExprTemporaries.push_back(E->getTemporary(I)); 2998 } 2999 } 3000 3001 // We already type-checked the argument, so we know it works. 3002 return Owned(CXXDefaultArgExpr::Create(Context, Param)); 3003} 3004 3005/// ConvertArgumentsForCall - Converts the arguments specified in 3006/// Args/NumArgs to the parameter types of the function FDecl with 3007/// function prototype Proto. Call is the call expression itself, and 3008/// Fn is the function expression. For a C++ member function, this 3009/// routine does not attempt to convert the object argument. Returns 3010/// true if the call is ill-formed. 3011bool 3012Sema::ConvertArgumentsForCall(CallExpr *Call, Expr *Fn, 3013 FunctionDecl *FDecl, 3014 const FunctionProtoType *Proto, 3015 Expr **Args, unsigned NumArgs, 3016 SourceLocation RParenLoc) { 3017 // C99 6.5.2.2p7 - the arguments are implicitly converted, as if by 3018 // assignment, to the types of the corresponding parameter, ... 3019 unsigned NumArgsInProto = Proto->getNumArgs(); 3020 bool Invalid = false; 3021 3022 // If too few arguments are available (and we don't have default 3023 // arguments for the remaining parameters), don't make the call. 3024 if (NumArgs < NumArgsInProto) { 3025 if (!FDecl || NumArgs < FDecl->getMinRequiredArguments()) 3026 return Diag(RParenLoc, diag::err_typecheck_call_too_few_args) 3027 << Fn->getType()->isBlockPointerType() << Fn->getSourceRange(); 3028 Call->setNumArgs(Context, NumArgsInProto); 3029 } 3030 3031 // If too many are passed and not variadic, error on the extras and drop 3032 // them. 3033 if (NumArgs > NumArgsInProto) { 3034 if (!Proto->isVariadic()) { 3035 Diag(Args[NumArgsInProto]->getLocStart(), 3036 diag::err_typecheck_call_too_many_args) 3037 << Fn->getType()->isBlockPointerType() << Fn->getSourceRange() 3038 << SourceRange(Args[NumArgsInProto]->getLocStart(), 3039 Args[NumArgs-1]->getLocEnd()); 3040 // This deletes the extra arguments. 3041 Call->setNumArgs(Context, NumArgsInProto); 3042 return true; 3043 } 3044 } 3045 llvm::SmallVector<Expr *, 8> AllArgs; 3046 VariadicCallType CallType = 3047 Proto->isVariadic() ? VariadicFunction : VariadicDoesNotApply; 3048 if (Fn->getType()->isBlockPointerType()) 3049 CallType = VariadicBlock; // Block 3050 else if (isa<MemberExpr>(Fn)) 3051 CallType = VariadicMethod; 3052 Invalid = GatherArgumentsForCall(Call->getSourceRange().getBegin(), FDecl, 3053 Proto, 0, Args, NumArgs, AllArgs, CallType); 3054 if (Invalid) 3055 return true; 3056 unsigned TotalNumArgs = AllArgs.size(); 3057 for (unsigned i = 0; i < TotalNumArgs; ++i) 3058 Call->setArg(i, AllArgs[i]); 3059 3060 return false; 3061} 3062 3063bool Sema::GatherArgumentsForCall(SourceLocation CallLoc, 3064 FunctionDecl *FDecl, 3065 const FunctionProtoType *Proto, 3066 unsigned FirstProtoArg, 3067 Expr **Args, unsigned NumArgs, 3068 llvm::SmallVector<Expr *, 8> &AllArgs, 3069 VariadicCallType CallType) { 3070 unsigned NumArgsInProto = Proto->getNumArgs(); 3071 unsigned NumArgsToCheck = NumArgs; 3072 bool Invalid = false; 3073 if (NumArgs != NumArgsInProto) 3074 // Use default arguments for missing arguments 3075 NumArgsToCheck = NumArgsInProto; 3076 unsigned ArgIx = 0; 3077 // Continue to check argument types (even if we have too few/many args). 3078 for (unsigned i = FirstProtoArg; i != NumArgsToCheck; i++) { 3079 QualType ProtoArgType = Proto->getArgType(i); 3080 3081 Expr *Arg; 3082 if (ArgIx < NumArgs) { 3083 Arg = Args[ArgIx++]; 3084 3085 if (RequireCompleteType(Arg->getSourceRange().getBegin(), 3086 ProtoArgType, 3087 PDiag(diag::err_call_incomplete_argument) 3088 << Arg->getSourceRange())) 3089 return true; 3090 3091 // Pass the argument. 3092 if (PerformCopyInitialization(Arg, ProtoArgType, "passing")) 3093 return true; 3094 3095 if (!ProtoArgType->isReferenceType()) 3096 Arg = MaybeBindToTemporary(Arg).takeAs<Expr>(); 3097 } else { 3098 ParmVarDecl *Param = FDecl->getParamDecl(i); 3099 3100 OwningExprResult ArgExpr = 3101 BuildCXXDefaultArgExpr(CallLoc, FDecl, Param); 3102 if (ArgExpr.isInvalid()) 3103 return true; 3104 3105 Arg = ArgExpr.takeAs<Expr>(); 3106 } 3107 AllArgs.push_back(Arg); 3108 } 3109 3110 // If this is a variadic call, handle args passed through "...". 3111 if (CallType != VariadicDoesNotApply) { 3112 // Promote the arguments (C99 6.5.2.2p7). 3113 for (unsigned i = ArgIx; i < NumArgs; i++) { 3114 Expr *Arg = Args[i]; 3115 Invalid |= DefaultVariadicArgumentPromotion(Arg, CallType); 3116 AllArgs.push_back(Arg); 3117 } 3118 } 3119 return Invalid; 3120} 3121 3122/// \brief "Deconstruct" the function argument of a call expression to find 3123/// the underlying declaration (if any), the name of the called function, 3124/// whether argument-dependent lookup is available, whether it has explicit 3125/// template arguments, etc. 3126void Sema::DeconstructCallFunction(Expr *FnExpr, 3127 llvm::SmallVectorImpl<NamedDecl*> &Fns, 3128 DeclarationName &Name, 3129 NestedNameSpecifier *&Qualifier, 3130 SourceRange &QualifierRange, 3131 bool &ArgumentDependentLookup, 3132 bool &Overloaded, 3133 bool &HasExplicitTemplateArguments, 3134 TemplateArgumentListInfo &ExplicitTemplateArgs) { 3135 // Set defaults for all of the output parameters. 3136 Name = DeclarationName(); 3137 Qualifier = 0; 3138 QualifierRange = SourceRange(); 3139 ArgumentDependentLookup = false; 3140 Overloaded = false; 3141 HasExplicitTemplateArguments = false; 3142 3143 // If we're directly calling a function, get the appropriate declaration. 3144 // Also, in C++, keep track of whether we should perform argument-dependent 3145 // lookup and whether there were any explicitly-specified template arguments. 3146 while (true) { 3147 if (ImplicitCastExpr *IcExpr = dyn_cast<ImplicitCastExpr>(FnExpr)) 3148 FnExpr = IcExpr->getSubExpr(); 3149 else if (ParenExpr *PExpr = dyn_cast<ParenExpr>(FnExpr)) { 3150 FnExpr = PExpr->getSubExpr(); 3151 } else if (isa<UnaryOperator>(FnExpr) && 3152 cast<UnaryOperator>(FnExpr)->getOpcode() 3153 == UnaryOperator::AddrOf) { 3154 FnExpr = cast<UnaryOperator>(FnExpr)->getSubExpr(); 3155 } else if (DeclRefExpr *DRExpr = dyn_cast<DeclRefExpr>(FnExpr)) { 3156 Fns.push_back(cast<NamedDecl>(DRExpr->getDecl())); 3157 ArgumentDependentLookup = false; 3158 if ((Qualifier = DRExpr->getQualifier())) 3159 QualifierRange = DRExpr->getQualifierRange(); 3160 break; 3161 } else if (UnresolvedLookupExpr *UnresLookup 3162 = dyn_cast<UnresolvedLookupExpr>(FnExpr)) { 3163 Name = UnresLookup->getName(); 3164 Fns.append(UnresLookup->decls_begin(), UnresLookup->decls_end()); 3165 ArgumentDependentLookup = UnresLookup->requiresADL(); 3166 Overloaded = UnresLookup->isOverloaded(); 3167 if ((Qualifier = UnresLookup->getQualifier())) 3168 QualifierRange = UnresLookup->getQualifierRange(); 3169 if (UnresLookup->hasExplicitTemplateArgs()) { 3170 HasExplicitTemplateArguments = true; 3171 UnresLookup->copyTemplateArgumentsInto(ExplicitTemplateArgs); 3172 } 3173 break; 3174 } else { 3175 break; 3176 } 3177 } 3178} 3179 3180/// ActOnCallExpr - Handle a call to Fn with the specified array of arguments. 3181/// This provides the location of the left/right parens and a list of comma 3182/// locations. 3183Action::OwningExprResult 3184Sema::ActOnCallExpr(Scope *S, ExprArg fn, SourceLocation LParenLoc, 3185 MultiExprArg args, 3186 SourceLocation *CommaLocs, SourceLocation RParenLoc) { 3187 unsigned NumArgs = args.size(); 3188 3189 // Since this might be a postfix expression, get rid of ParenListExprs. 3190 fn = MaybeConvertParenListExprToParenExpr(S, move(fn)); 3191 3192 Expr *Fn = fn.takeAs<Expr>(); 3193 Expr **Args = reinterpret_cast<Expr**>(args.release()); 3194 assert(Fn && "no function call expression"); 3195 3196 if (getLangOptions().CPlusPlus) { 3197 // If this is a pseudo-destructor expression, build the call immediately. 3198 if (isa<CXXPseudoDestructorExpr>(Fn)) { 3199 if (NumArgs > 0) { 3200 // Pseudo-destructor calls should not have any arguments. 3201 Diag(Fn->getLocStart(), diag::err_pseudo_dtor_call_with_args) 3202 << CodeModificationHint::CreateRemoval( 3203 SourceRange(Args[0]->getLocStart(), 3204 Args[NumArgs-1]->getLocEnd())); 3205 3206 for (unsigned I = 0; I != NumArgs; ++I) 3207 Args[I]->Destroy(Context); 3208 3209 NumArgs = 0; 3210 } 3211 3212 return Owned(new (Context) CallExpr(Context, Fn, 0, 0, Context.VoidTy, 3213 RParenLoc)); 3214 } 3215 3216 // Determine whether this is a dependent call inside a C++ template, 3217 // in which case we won't do any semantic analysis now. 3218 // FIXME: Will need to cache the results of name lookup (including ADL) in 3219 // Fn. 3220 bool Dependent = false; 3221 if (Fn->isTypeDependent()) 3222 Dependent = true; 3223 else if (Expr::hasAnyTypeDependentArguments(Args, NumArgs)) 3224 Dependent = true; 3225 3226 if (Dependent) 3227 return Owned(new (Context) CallExpr(Context, Fn, Args, NumArgs, 3228 Context.DependentTy, RParenLoc)); 3229 3230 // Determine whether this is a call to an object (C++ [over.call.object]). 3231 if (Fn->getType()->isRecordType()) 3232 return Owned(BuildCallToObjectOfClassType(S, Fn, LParenLoc, Args, NumArgs, 3233 CommaLocs, RParenLoc)); 3234 3235 Expr *NakedFn = Fn->IgnoreParens(); 3236 3237 // Determine whether this is a call to an unresolved member function. 3238 if (UnresolvedMemberExpr *MemE = dyn_cast<UnresolvedMemberExpr>(NakedFn)) { 3239 // If lookup was unresolved but not dependent (i.e. didn't find 3240 // an unresolved using declaration), it has to be an overloaded 3241 // function set, which means it must contain either multiple 3242 // declarations (all methods or method templates) or a single 3243 // method template. 3244 assert((MemE->getNumDecls() > 1) || 3245 isa<FunctionTemplateDecl>(*MemE->decls_begin())); 3246 (void)MemE; 3247 3248 return BuildCallToMemberFunction(S, Fn, LParenLoc, Args, NumArgs, 3249 CommaLocs, RParenLoc); 3250 } 3251 3252 // Determine whether this is a call to a member function. 3253 if (MemberExpr *MemExpr = dyn_cast<MemberExpr>(NakedFn)) { 3254 NamedDecl *MemDecl = MemExpr->getMemberDecl(); 3255 if (isa<CXXMethodDecl>(MemDecl)) 3256 return BuildCallToMemberFunction(S, Fn, LParenLoc, Args, NumArgs, 3257 CommaLocs, RParenLoc); 3258 } 3259 3260 // Determine whether this is a call to a pointer-to-member function. 3261 if (BinaryOperator *BO = dyn_cast<BinaryOperator>(NakedFn)) { 3262 if (BO->getOpcode() == BinaryOperator::PtrMemD || 3263 BO->getOpcode() == BinaryOperator::PtrMemI) { 3264 if (const FunctionProtoType *FPT = 3265 dyn_cast<FunctionProtoType>(BO->getType())) { 3266 QualType ResultTy = FPT->getResultType().getNonReferenceType(); 3267 3268 ExprOwningPtr<CXXMemberCallExpr> 3269 TheCall(this, new (Context) CXXMemberCallExpr(Context, BO, Args, 3270 NumArgs, ResultTy, 3271 RParenLoc)); 3272 3273 if (CheckCallReturnType(FPT->getResultType(), 3274 BO->getRHS()->getSourceRange().getBegin(), 3275 TheCall.get(), 0)) 3276 return ExprError(); 3277 3278 if (ConvertArgumentsForCall(&*TheCall, BO, 0, FPT, Args, NumArgs, 3279 RParenLoc)) 3280 return ExprError(); 3281 3282 return Owned(MaybeBindToTemporary(TheCall.release()).release()); 3283 } 3284 return ExprError(Diag(Fn->getLocStart(), 3285 diag::err_typecheck_call_not_function) 3286 << Fn->getType() << Fn->getSourceRange()); 3287 } 3288 } 3289 } 3290 3291 // If we're directly calling a function, get the appropriate declaration. 3292 // Also, in C++, keep track of whether we should perform argument-dependent 3293 // lookup and whether there were any explicitly-specified template arguments. 3294 llvm::SmallVector<NamedDecl*,8> Fns; 3295 DeclarationName UnqualifiedName; 3296 bool Overloaded; 3297 bool ADL; 3298 bool HasExplicitTemplateArgs = 0; 3299 TemplateArgumentListInfo ExplicitTemplateArgs; 3300 NestedNameSpecifier *Qualifier = 0; 3301 SourceRange QualifierRange; 3302 DeconstructCallFunction(Fn, Fns, UnqualifiedName, Qualifier, QualifierRange, 3303 ADL, Overloaded, HasExplicitTemplateArgs, 3304 ExplicitTemplateArgs); 3305 3306 NamedDecl *NDecl; // the specific declaration we're calling, if applicable 3307 FunctionDecl *FDecl; // same, if it's known to be a function 3308 3309 if (Overloaded || ADL) { 3310#ifndef NDEBUG 3311 if (ADL) { 3312 // To do ADL, we must have found an unqualified name. 3313 assert(UnqualifiedName && "found no unqualified name for ADL"); 3314 3315 // We don't perform ADL for implicit declarations of builtins. 3316 // Verify that this was correctly set up. 3317 if (Fns.size() == 1 && (FDecl = dyn_cast<FunctionDecl>(Fns[0])) && 3318 FDecl->getBuiltinID() && FDecl->isImplicit()) 3319 assert(0 && "performing ADL for builtin"); 3320 3321 // We don't perform ADL in C. 3322 assert(getLangOptions().CPlusPlus && "ADL enabled in C"); 3323 } 3324 3325 if (Overloaded) { 3326 // To be overloaded, we must either have multiple functions or 3327 // at least one function template (which is effectively an 3328 // infinite set of functions). 3329 assert((Fns.size() > 1 || 3330 (Fns.size() == 1 && 3331 isa<FunctionTemplateDecl>(Fns[0]->getUnderlyingDecl()))) 3332 && "unrecognized overload situation"); 3333 } 3334#endif 3335 3336 FDecl = ResolveOverloadedCallFn(Fn, Fns, UnqualifiedName, 3337 (HasExplicitTemplateArgs ? &ExplicitTemplateArgs : 0), 3338 LParenLoc, Args, NumArgs, CommaLocs, 3339 RParenLoc, ADL); 3340 if (!FDecl) 3341 return ExprError(); 3342 3343 Fn = FixOverloadedFunctionReference(Fn, FDecl); 3344 3345 NDecl = FDecl; 3346 } else { 3347 assert(Fns.size() <= 1 && "overloaded without Overloaded flag"); 3348 if (Fns.empty()) 3349 NDecl = 0; 3350 else { 3351 NDecl = Fns[0]; 3352 } 3353 } 3354 3355 return BuildResolvedCallExpr(Fn, NDecl, LParenLoc, Args, NumArgs, RParenLoc); 3356} 3357 3358/// BuildCallExpr - Build a call to a resolved expression, i.e. an 3359/// expression not of \p OverloadTy. The expression should 3360/// unary-convert to an expression of function-pointer or 3361/// block-pointer type. 3362/// 3363/// \param NDecl the declaration being called, if available 3364Sema::OwningExprResult 3365Sema::BuildResolvedCallExpr(Expr *Fn, NamedDecl *NDecl, 3366 SourceLocation LParenLoc, 3367 Expr **Args, unsigned NumArgs, 3368 SourceLocation RParenLoc) { 3369 FunctionDecl *FDecl = dyn_cast_or_null<FunctionDecl>(NDecl); 3370 3371 // Promote the function operand. 3372 UsualUnaryConversions(Fn); 3373 3374 // Make the call expr early, before semantic checks. This guarantees cleanup 3375 // of arguments and function on error. 3376 ExprOwningPtr<CallExpr> TheCall(this, new (Context) CallExpr(Context, Fn, 3377 Args, NumArgs, 3378 Context.BoolTy, 3379 RParenLoc)); 3380 3381 const FunctionType *FuncT; 3382 if (!Fn->getType()->isBlockPointerType()) { 3383 // C99 6.5.2.2p1 - "The expression that denotes the called function shall 3384 // have type pointer to function". 3385 const PointerType *PT = Fn->getType()->getAs<PointerType>(); 3386 if (PT == 0) 3387 return ExprError(Diag(LParenLoc, diag::err_typecheck_call_not_function) 3388 << Fn->getType() << Fn->getSourceRange()); 3389 FuncT = PT->getPointeeType()->getAs<FunctionType>(); 3390 } else { // This is a block call. 3391 FuncT = Fn->getType()->getAs<BlockPointerType>()->getPointeeType()-> 3392 getAs<FunctionType>(); 3393 } 3394 if (FuncT == 0) 3395 return ExprError(Diag(LParenLoc, diag::err_typecheck_call_not_function) 3396 << Fn->getType() << Fn->getSourceRange()); 3397 3398 // Check for a valid return type 3399 if (CheckCallReturnType(FuncT->getResultType(), 3400 Fn->getSourceRange().getBegin(), TheCall.get(), 3401 FDecl)) 3402 return ExprError(); 3403 3404 // We know the result type of the call, set it. 3405 TheCall->setType(FuncT->getResultType().getNonReferenceType()); 3406 3407 if (const FunctionProtoType *Proto = dyn_cast<FunctionProtoType>(FuncT)) { 3408 if (ConvertArgumentsForCall(&*TheCall, Fn, FDecl, Proto, Args, NumArgs, 3409 RParenLoc)) 3410 return ExprError(); 3411 } else { 3412 assert(isa<FunctionNoProtoType>(FuncT) && "Unknown FunctionType!"); 3413 3414 if (FDecl) { 3415 // Check if we have too few/too many template arguments, based 3416 // on our knowledge of the function definition. 3417 const FunctionDecl *Def = 0; 3418 if (FDecl->getBody(Def) && NumArgs != Def->param_size()) { 3419 const FunctionProtoType *Proto = 3420 Def->getType()->getAs<FunctionProtoType>(); 3421 if (!Proto || !(Proto->isVariadic() && NumArgs >= Def->param_size())) { 3422 Diag(RParenLoc, diag::warn_call_wrong_number_of_arguments) 3423 << (NumArgs > Def->param_size()) << FDecl << Fn->getSourceRange(); 3424 } 3425 } 3426 } 3427 3428 // Promote the arguments (C99 6.5.2.2p6). 3429 for (unsigned i = 0; i != NumArgs; i++) { 3430 Expr *Arg = Args[i]; 3431 DefaultArgumentPromotion(Arg); 3432 if (RequireCompleteType(Arg->getSourceRange().getBegin(), 3433 Arg->getType(), 3434 PDiag(diag::err_call_incomplete_argument) 3435 << Arg->getSourceRange())) 3436 return ExprError(); 3437 TheCall->setArg(i, Arg); 3438 } 3439 } 3440 3441 if (CXXMethodDecl *Method = dyn_cast_or_null<CXXMethodDecl>(FDecl)) 3442 if (!Method->isStatic()) 3443 return ExprError(Diag(LParenLoc, diag::err_member_call_without_object) 3444 << Fn->getSourceRange()); 3445 3446 // Check for sentinels 3447 if (NDecl) 3448 DiagnoseSentinelCalls(NDecl, LParenLoc, Args, NumArgs); 3449 3450 // Do special checking on direct calls to functions. 3451 if (FDecl) { 3452 if (CheckFunctionCall(FDecl, TheCall.get())) 3453 return ExprError(); 3454 3455 if (unsigned BuiltinID = FDecl->getBuiltinID()) 3456 return CheckBuiltinFunctionCall(BuiltinID, TheCall.take()); 3457 } else if (NDecl) { 3458 if (CheckBlockCall(NDecl, TheCall.get())) 3459 return ExprError(); 3460 } 3461 3462 return MaybeBindToTemporary(TheCall.take()); 3463} 3464 3465Action::OwningExprResult 3466Sema::ActOnCompoundLiteral(SourceLocation LParenLoc, TypeTy *Ty, 3467 SourceLocation RParenLoc, ExprArg InitExpr) { 3468 assert((Ty != 0) && "ActOnCompoundLiteral(): missing type"); 3469 //FIXME: Preserve type source info. 3470 QualType literalType = GetTypeFromParser(Ty); 3471 // FIXME: put back this assert when initializers are worked out. 3472 //assert((InitExpr != 0) && "ActOnCompoundLiteral(): missing expression"); 3473 Expr *literalExpr = static_cast<Expr*>(InitExpr.get()); 3474 3475 if (literalType->isArrayType()) { 3476 if (literalType->isVariableArrayType()) 3477 return ExprError(Diag(LParenLoc, diag::err_variable_object_no_init) 3478 << SourceRange(LParenLoc, literalExpr->getSourceRange().getEnd())); 3479 } else if (!literalType->isDependentType() && 3480 RequireCompleteType(LParenLoc, literalType, 3481 PDiag(diag::err_typecheck_decl_incomplete_type) 3482 << SourceRange(LParenLoc, 3483 literalExpr->getSourceRange().getEnd()))) 3484 return ExprError(); 3485 3486 if (CheckInitializerTypes(literalExpr, literalType, LParenLoc, 3487 DeclarationName(), /*FIXME:DirectInit=*/false)) 3488 return ExprError(); 3489 3490 bool isFileScope = getCurFunctionOrMethodDecl() == 0; 3491 if (isFileScope) { // 6.5.2.5p3 3492 if (CheckForConstantInitializer(literalExpr, literalType)) 3493 return ExprError(); 3494 } 3495 InitExpr.release(); 3496 return Owned(new (Context) CompoundLiteralExpr(LParenLoc, literalType, 3497 literalExpr, isFileScope)); 3498} 3499 3500Action::OwningExprResult 3501Sema::ActOnInitList(SourceLocation LBraceLoc, MultiExprArg initlist, 3502 SourceLocation RBraceLoc) { 3503 unsigned NumInit = initlist.size(); 3504 Expr **InitList = reinterpret_cast<Expr**>(initlist.release()); 3505 3506 // Semantic analysis for initializers is done by ActOnDeclarator() and 3507 // CheckInitializer() - it requires knowledge of the object being intialized. 3508 3509 InitListExpr *E = new (Context) InitListExpr(LBraceLoc, InitList, NumInit, 3510 RBraceLoc); 3511 E->setType(Context.VoidTy); // FIXME: just a place holder for now. 3512 return Owned(E); 3513} 3514 3515static CastExpr::CastKind getScalarCastKind(ASTContext &Context, 3516 QualType SrcTy, QualType DestTy) { 3517 if (Context.hasSameUnqualifiedType(SrcTy, DestTy)) 3518 return CastExpr::CK_NoOp; 3519 3520 if (SrcTy->hasPointerRepresentation()) { 3521 if (DestTy->hasPointerRepresentation()) 3522 return CastExpr::CK_BitCast; 3523 if (DestTy->isIntegerType()) 3524 return CastExpr::CK_PointerToIntegral; 3525 } 3526 3527 if (SrcTy->isIntegerType()) { 3528 if (DestTy->isIntegerType()) 3529 return CastExpr::CK_IntegralCast; 3530 if (DestTy->hasPointerRepresentation()) 3531 return CastExpr::CK_IntegralToPointer; 3532 if (DestTy->isRealFloatingType()) 3533 return CastExpr::CK_IntegralToFloating; 3534 } 3535 3536 if (SrcTy->isRealFloatingType()) { 3537 if (DestTy->isRealFloatingType()) 3538 return CastExpr::CK_FloatingCast; 3539 if (DestTy->isIntegerType()) 3540 return CastExpr::CK_FloatingToIntegral; 3541 } 3542 3543 // FIXME: Assert here. 3544 // assert(false && "Unhandled cast combination!"); 3545 return CastExpr::CK_Unknown; 3546} 3547 3548/// CheckCastTypes - Check type constraints for casting between types. 3549bool Sema::CheckCastTypes(SourceRange TyR, QualType castType, Expr *&castExpr, 3550 CastExpr::CastKind& Kind, 3551 CXXMethodDecl *& ConversionDecl, 3552 bool FunctionalStyle) { 3553 if (getLangOptions().CPlusPlus) 3554 return CXXCheckCStyleCast(TyR, castType, castExpr, Kind, FunctionalStyle, 3555 ConversionDecl); 3556 3557 DefaultFunctionArrayConversion(castExpr); 3558 3559 // C99 6.5.4p2: the cast type needs to be void or scalar and the expression 3560 // type needs to be scalar. 3561 if (castType->isVoidType()) { 3562 // Cast to void allows any expr type. 3563 Kind = CastExpr::CK_ToVoid; 3564 return false; 3565 } 3566 3567 if (!castType->isScalarType() && !castType->isVectorType()) { 3568 if (Context.hasSameUnqualifiedType(castType, castExpr->getType()) && 3569 (castType->isStructureType() || castType->isUnionType())) { 3570 // GCC struct/union extension: allow cast to self. 3571 // FIXME: Check that the cast destination type is complete. 3572 Diag(TyR.getBegin(), diag::ext_typecheck_cast_nonscalar) 3573 << castType << castExpr->getSourceRange(); 3574 Kind = CastExpr::CK_NoOp; 3575 return false; 3576 } 3577 3578 if (castType->isUnionType()) { 3579 // GCC cast to union extension 3580 RecordDecl *RD = castType->getAs<RecordType>()->getDecl(); 3581 RecordDecl::field_iterator Field, FieldEnd; 3582 for (Field = RD->field_begin(), FieldEnd = RD->field_end(); 3583 Field != FieldEnd; ++Field) { 3584 if (Context.hasSameUnqualifiedType(Field->getType(), 3585 castExpr->getType())) { 3586 Diag(TyR.getBegin(), diag::ext_typecheck_cast_to_union) 3587 << castExpr->getSourceRange(); 3588 break; 3589 } 3590 } 3591 if (Field == FieldEnd) 3592 return Diag(TyR.getBegin(), diag::err_typecheck_cast_to_union_no_type) 3593 << castExpr->getType() << castExpr->getSourceRange(); 3594 Kind = CastExpr::CK_ToUnion; 3595 return false; 3596 } 3597 3598 // Reject any other conversions to non-scalar types. 3599 return Diag(TyR.getBegin(), diag::err_typecheck_cond_expect_scalar) 3600 << castType << castExpr->getSourceRange(); 3601 } 3602 3603 if (!castExpr->getType()->isScalarType() && 3604 !castExpr->getType()->isVectorType()) { 3605 return Diag(castExpr->getLocStart(), 3606 diag::err_typecheck_expect_scalar_operand) 3607 << castExpr->getType() << castExpr->getSourceRange(); 3608 } 3609 3610 if (castType->isExtVectorType()) 3611 return CheckExtVectorCast(TyR, castType, castExpr, Kind); 3612 3613 if (castType->isVectorType()) 3614 return CheckVectorCast(TyR, castType, castExpr->getType(), Kind); 3615 if (castExpr->getType()->isVectorType()) 3616 return CheckVectorCast(TyR, castExpr->getType(), castType, Kind); 3617 3618 if (getLangOptions().ObjC1 && isa<ObjCSuperExpr>(castExpr)) 3619 return Diag(castExpr->getLocStart(), diag::err_illegal_super_cast) << TyR; 3620 3621 if (isa<ObjCSelectorExpr>(castExpr)) 3622 return Diag(castExpr->getLocStart(), diag::err_cast_selector_expr); 3623 3624 if (!castType->isArithmeticType()) { 3625 QualType castExprType = castExpr->getType(); 3626 if (!castExprType->isIntegralType() && castExprType->isArithmeticType()) 3627 return Diag(castExpr->getLocStart(), 3628 diag::err_cast_pointer_from_non_pointer_int) 3629 << castExprType << castExpr->getSourceRange(); 3630 } else if (!castExpr->getType()->isArithmeticType()) { 3631 if (!castType->isIntegralType() && castType->isArithmeticType()) 3632 return Diag(castExpr->getLocStart(), 3633 diag::err_cast_pointer_to_non_pointer_int) 3634 << castType << castExpr->getSourceRange(); 3635 } 3636 3637 Kind = getScalarCastKind(Context, castExpr->getType(), castType); 3638 return false; 3639} 3640 3641bool Sema::CheckVectorCast(SourceRange R, QualType VectorTy, QualType Ty, 3642 CastExpr::CastKind &Kind) { 3643 assert(VectorTy->isVectorType() && "Not a vector type!"); 3644 3645 if (Ty->isVectorType() || Ty->isIntegerType()) { 3646 if (Context.getTypeSize(VectorTy) != Context.getTypeSize(Ty)) 3647 return Diag(R.getBegin(), 3648 Ty->isVectorType() ? 3649 diag::err_invalid_conversion_between_vectors : 3650 diag::err_invalid_conversion_between_vector_and_integer) 3651 << VectorTy << Ty << R; 3652 } else 3653 return Diag(R.getBegin(), 3654 diag::err_invalid_conversion_between_vector_and_scalar) 3655 << VectorTy << Ty << R; 3656 3657 Kind = CastExpr::CK_BitCast; 3658 return false; 3659} 3660 3661bool Sema::CheckExtVectorCast(SourceRange R, QualType DestTy, Expr *&CastExpr, 3662 CastExpr::CastKind &Kind) { 3663 assert(DestTy->isExtVectorType() && "Not an extended vector type!"); 3664 3665 QualType SrcTy = CastExpr->getType(); 3666 3667 // If SrcTy is a VectorType, the total size must match to explicitly cast to 3668 // an ExtVectorType. 3669 if (SrcTy->isVectorType()) { 3670 if (Context.getTypeSize(DestTy) != Context.getTypeSize(SrcTy)) 3671 return Diag(R.getBegin(),diag::err_invalid_conversion_between_ext_vectors) 3672 << DestTy << SrcTy << R; 3673 Kind = CastExpr::CK_BitCast; 3674 return false; 3675 } 3676 3677 // All non-pointer scalars can be cast to ExtVector type. The appropriate 3678 // conversion will take place first from scalar to elt type, and then 3679 // splat from elt type to vector. 3680 if (SrcTy->isPointerType()) 3681 return Diag(R.getBegin(), 3682 diag::err_invalid_conversion_between_vector_and_scalar) 3683 << DestTy << SrcTy << R; 3684 3685 QualType DestElemTy = DestTy->getAs<ExtVectorType>()->getElementType(); 3686 ImpCastExprToType(CastExpr, DestElemTy, 3687 getScalarCastKind(Context, SrcTy, DestElemTy)); 3688 3689 Kind = CastExpr::CK_VectorSplat; 3690 return false; 3691} 3692 3693Action::OwningExprResult 3694Sema::ActOnCastExpr(Scope *S, SourceLocation LParenLoc, TypeTy *Ty, 3695 SourceLocation RParenLoc, ExprArg Op) { 3696 CastExpr::CastKind Kind = CastExpr::CK_Unknown; 3697 3698 assert((Ty != 0) && (Op.get() != 0) && 3699 "ActOnCastExpr(): missing type or expr"); 3700 3701 Expr *castExpr = (Expr *)Op.get(); 3702 //FIXME: Preserve type source info. 3703 QualType castType = GetTypeFromParser(Ty); 3704 3705 // If the Expr being casted is a ParenListExpr, handle it specially. 3706 if (isa<ParenListExpr>(castExpr)) 3707 return ActOnCastOfParenListExpr(S, LParenLoc, RParenLoc, move(Op),castType); 3708 CXXMethodDecl *Method = 0; 3709 if (CheckCastTypes(SourceRange(LParenLoc, RParenLoc), castType, castExpr, 3710 Kind, Method)) 3711 return ExprError(); 3712 3713 if (Method) { 3714 OwningExprResult CastArg = BuildCXXCastArgument(LParenLoc, castType, Kind, 3715 Method, move(Op)); 3716 3717 if (CastArg.isInvalid()) 3718 return ExprError(); 3719 3720 castExpr = CastArg.takeAs<Expr>(); 3721 } else { 3722 Op.release(); 3723 } 3724 3725 return Owned(new (Context) CStyleCastExpr(castType.getNonReferenceType(), 3726 Kind, castExpr, castType, 3727 LParenLoc, RParenLoc)); 3728} 3729 3730/// This is not an AltiVec-style cast, so turn the ParenListExpr into a sequence 3731/// of comma binary operators. 3732Action::OwningExprResult 3733Sema::MaybeConvertParenListExprToParenExpr(Scope *S, ExprArg EA) { 3734 Expr *expr = EA.takeAs<Expr>(); 3735 ParenListExpr *E = dyn_cast<ParenListExpr>(expr); 3736 if (!E) 3737 return Owned(expr); 3738 3739 OwningExprResult Result(*this, E->getExpr(0)); 3740 3741 for (unsigned i = 1, e = E->getNumExprs(); i != e && !Result.isInvalid(); ++i) 3742 Result = ActOnBinOp(S, E->getExprLoc(), tok::comma, move(Result), 3743 Owned(E->getExpr(i))); 3744 3745 return ActOnParenExpr(E->getLParenLoc(), E->getRParenLoc(), move(Result)); 3746} 3747 3748Action::OwningExprResult 3749Sema::ActOnCastOfParenListExpr(Scope *S, SourceLocation LParenLoc, 3750 SourceLocation RParenLoc, ExprArg Op, 3751 QualType Ty) { 3752 ParenListExpr *PE = (ParenListExpr *)Op.get(); 3753 3754 // If this is an altivec initializer, '(' type ')' '(' init, ..., init ')' 3755 // then handle it as such. 3756 if (getLangOptions().AltiVec && Ty->isVectorType()) { 3757 if (PE->getNumExprs() == 0) { 3758 Diag(PE->getExprLoc(), diag::err_altivec_empty_initializer); 3759 return ExprError(); 3760 } 3761 3762 llvm::SmallVector<Expr *, 8> initExprs; 3763 for (unsigned i = 0, e = PE->getNumExprs(); i != e; ++i) 3764 initExprs.push_back(PE->getExpr(i)); 3765 3766 // FIXME: This means that pretty-printing the final AST will produce curly 3767 // braces instead of the original commas. 3768 Op.release(); 3769 InitListExpr *E = new (Context) InitListExpr(LParenLoc, &initExprs[0], 3770 initExprs.size(), RParenLoc); 3771 E->setType(Ty); 3772 return ActOnCompoundLiteral(LParenLoc, Ty.getAsOpaquePtr(), RParenLoc, 3773 Owned(E)); 3774 } else { 3775 // This is not an AltiVec-style cast, so turn the ParenListExpr into a 3776 // sequence of BinOp comma operators. 3777 Op = MaybeConvertParenListExprToParenExpr(S, move(Op)); 3778 return ActOnCastExpr(S, LParenLoc, Ty.getAsOpaquePtr(), RParenLoc,move(Op)); 3779 } 3780} 3781 3782Action::OwningExprResult Sema::ActOnParenOrParenListExpr(SourceLocation L, 3783 SourceLocation R, 3784 MultiExprArg Val, 3785 TypeTy *TypeOfCast) { 3786 unsigned nexprs = Val.size(); 3787 Expr **exprs = reinterpret_cast<Expr**>(Val.release()); 3788 assert((exprs != 0) && "ActOnParenOrParenListExpr() missing expr list"); 3789 Expr *expr; 3790 if (nexprs == 1 && TypeOfCast && !TypeIsVectorType(TypeOfCast)) 3791 expr = new (Context) ParenExpr(L, R, exprs[0]); 3792 else 3793 expr = new (Context) ParenListExpr(Context, L, exprs, nexprs, R); 3794 return Owned(expr); 3795} 3796 3797/// Note that lhs is not null here, even if this is the gnu "x ?: y" extension. 3798/// In that case, lhs = cond. 3799/// C99 6.5.15 3800QualType Sema::CheckConditionalOperands(Expr *&Cond, Expr *&LHS, Expr *&RHS, 3801 SourceLocation QuestionLoc) { 3802 // C++ is sufficiently different to merit its own checker. 3803 if (getLangOptions().CPlusPlus) 3804 return CXXCheckConditionalOperands(Cond, LHS, RHS, QuestionLoc); 3805 3806 CheckSignCompare(LHS, RHS, QuestionLoc, diag::warn_mixed_sign_conditional); 3807 3808 UsualUnaryConversions(Cond); 3809 UsualUnaryConversions(LHS); 3810 UsualUnaryConversions(RHS); 3811 QualType CondTy = Cond->getType(); 3812 QualType LHSTy = LHS->getType(); 3813 QualType RHSTy = RHS->getType(); 3814 3815 // first, check the condition. 3816 if (!CondTy->isScalarType()) { // C99 6.5.15p2 3817 Diag(Cond->getLocStart(), diag::err_typecheck_cond_expect_scalar) 3818 << CondTy; 3819 return QualType(); 3820 } 3821 3822 // Now check the two expressions. 3823 if (LHSTy->isVectorType() || RHSTy->isVectorType()) 3824 return CheckVectorOperands(QuestionLoc, LHS, RHS); 3825 3826 // If both operands have arithmetic type, do the usual arithmetic conversions 3827 // to find a common type: C99 6.5.15p3,5. 3828 if (LHSTy->isArithmeticType() && RHSTy->isArithmeticType()) { 3829 UsualArithmeticConversions(LHS, RHS); 3830 return LHS->getType(); 3831 } 3832 3833 // If both operands are the same structure or union type, the result is that 3834 // type. 3835 if (const RecordType *LHSRT = LHSTy->getAs<RecordType>()) { // C99 6.5.15p3 3836 if (const RecordType *RHSRT = RHSTy->getAs<RecordType>()) 3837 if (LHSRT->getDecl() == RHSRT->getDecl()) 3838 // "If both the operands have structure or union type, the result has 3839 // that type." This implies that CV qualifiers are dropped. 3840 return LHSTy.getUnqualifiedType(); 3841 // FIXME: Type of conditional expression must be complete in C mode. 3842 } 3843 3844 // C99 6.5.15p5: "If both operands have void type, the result has void type." 3845 // The following || allows only one side to be void (a GCC-ism). 3846 if (LHSTy->isVoidType() || RHSTy->isVoidType()) { 3847 if (!LHSTy->isVoidType()) 3848 Diag(RHS->getLocStart(), diag::ext_typecheck_cond_one_void) 3849 << RHS->getSourceRange(); 3850 if (!RHSTy->isVoidType()) 3851 Diag(LHS->getLocStart(), diag::ext_typecheck_cond_one_void) 3852 << LHS->getSourceRange(); 3853 ImpCastExprToType(LHS, Context.VoidTy, CastExpr::CK_ToVoid); 3854 ImpCastExprToType(RHS, Context.VoidTy, CastExpr::CK_ToVoid); 3855 return Context.VoidTy; 3856 } 3857 // C99 6.5.15p6 - "if one operand is a null pointer constant, the result has 3858 // the type of the other operand." 3859 if ((LHSTy->isAnyPointerType() || LHSTy->isBlockPointerType()) && 3860 RHS->isNullPointerConstant(Context, Expr::NPC_ValueDependentIsNull)) { 3861 // promote the null to a pointer. 3862 ImpCastExprToType(RHS, LHSTy, CastExpr::CK_Unknown); 3863 return LHSTy; 3864 } 3865 if ((RHSTy->isAnyPointerType() || RHSTy->isBlockPointerType()) && 3866 LHS->isNullPointerConstant(Context, Expr::NPC_ValueDependentIsNull)) { 3867 ImpCastExprToType(LHS, RHSTy, CastExpr::CK_Unknown); 3868 return RHSTy; 3869 } 3870 // Handle things like Class and struct objc_class*. Here we case the result 3871 // to the pseudo-builtin, because that will be implicitly cast back to the 3872 // redefinition type if an attempt is made to access its fields. 3873 if (LHSTy->isObjCClassType() && 3874 (RHSTy.getDesugaredType() == Context.ObjCClassRedefinitionType)) { 3875 ImpCastExprToType(RHS, LHSTy, CastExpr::CK_BitCast); 3876 return LHSTy; 3877 } 3878 if (RHSTy->isObjCClassType() && 3879 (LHSTy.getDesugaredType() == Context.ObjCClassRedefinitionType)) { 3880 ImpCastExprToType(LHS, RHSTy, CastExpr::CK_BitCast); 3881 return RHSTy; 3882 } 3883 // And the same for struct objc_object* / id 3884 if (LHSTy->isObjCIdType() && 3885 (RHSTy.getDesugaredType() == Context.ObjCIdRedefinitionType)) { 3886 ImpCastExprToType(RHS, LHSTy, CastExpr::CK_BitCast); 3887 return LHSTy; 3888 } 3889 if (RHSTy->isObjCIdType() && 3890 (LHSTy.getDesugaredType() == Context.ObjCIdRedefinitionType)) { 3891 ImpCastExprToType(LHS, RHSTy, CastExpr::CK_BitCast); 3892 return RHSTy; 3893 } 3894 // And the same for struct objc_selector* / SEL 3895 if (Context.isObjCSelType(LHSTy) && 3896 (RHSTy.getDesugaredType() == Context.ObjCSelRedefinitionType)) { 3897 ImpCastExprToType(RHS, LHSTy, CastExpr::CK_BitCast); 3898 return LHSTy; 3899 } 3900 if (Context.isObjCSelType(RHSTy) && 3901 (LHSTy.getDesugaredType() == Context.ObjCSelRedefinitionType)) { 3902 ImpCastExprToType(LHS, RHSTy, CastExpr::CK_BitCast); 3903 return RHSTy; 3904 } 3905 // Handle block pointer types. 3906 if (LHSTy->isBlockPointerType() || RHSTy->isBlockPointerType()) { 3907 if (!LHSTy->isBlockPointerType() || !RHSTy->isBlockPointerType()) { 3908 if (LHSTy->isVoidPointerType() || RHSTy->isVoidPointerType()) { 3909 QualType destType = Context.getPointerType(Context.VoidTy); 3910 ImpCastExprToType(LHS, destType, CastExpr::CK_BitCast); 3911 ImpCastExprToType(RHS, destType, CastExpr::CK_BitCast); 3912 return destType; 3913 } 3914 Diag(QuestionLoc, diag::err_typecheck_cond_incompatible_operands) 3915 << LHSTy << RHSTy << LHS->getSourceRange() << RHS->getSourceRange(); 3916 return QualType(); 3917 } 3918 // We have 2 block pointer types. 3919 if (Context.getCanonicalType(LHSTy) == Context.getCanonicalType(RHSTy)) { 3920 // Two identical block pointer types are always compatible. 3921 return LHSTy; 3922 } 3923 // The block pointer types aren't identical, continue checking. 3924 QualType lhptee = LHSTy->getAs<BlockPointerType>()->getPointeeType(); 3925 QualType rhptee = RHSTy->getAs<BlockPointerType>()->getPointeeType(); 3926 3927 if (!Context.typesAreCompatible(lhptee.getUnqualifiedType(), 3928 rhptee.getUnqualifiedType())) { 3929 Diag(QuestionLoc, diag::warn_typecheck_cond_incompatible_pointers) 3930 << LHSTy << RHSTy << LHS->getSourceRange() << RHS->getSourceRange(); 3931 // In this situation, we assume void* type. No especially good 3932 // reason, but this is what gcc does, and we do have to pick 3933 // to get a consistent AST. 3934 QualType incompatTy = Context.getPointerType(Context.VoidTy); 3935 ImpCastExprToType(LHS, incompatTy, CastExpr::CK_BitCast); 3936 ImpCastExprToType(RHS, incompatTy, CastExpr::CK_BitCast); 3937 return incompatTy; 3938 } 3939 // The block pointer types are compatible. 3940 ImpCastExprToType(LHS, LHSTy, CastExpr::CK_BitCast); 3941 ImpCastExprToType(RHS, LHSTy, CastExpr::CK_BitCast); 3942 return LHSTy; 3943 } 3944 // Check constraints for Objective-C object pointers types. 3945 if (LHSTy->isObjCObjectPointerType() && RHSTy->isObjCObjectPointerType()) { 3946 3947 if (Context.getCanonicalType(LHSTy) == Context.getCanonicalType(RHSTy)) { 3948 // Two identical object pointer types are always compatible. 3949 return LHSTy; 3950 } 3951 const ObjCObjectPointerType *LHSOPT = LHSTy->getAs<ObjCObjectPointerType>(); 3952 const ObjCObjectPointerType *RHSOPT = RHSTy->getAs<ObjCObjectPointerType>(); 3953 QualType compositeType = LHSTy; 3954 3955 // If both operands are interfaces and either operand can be 3956 // assigned to the other, use that type as the composite 3957 // type. This allows 3958 // xxx ? (A*) a : (B*) b 3959 // where B is a subclass of A. 3960 // 3961 // Additionally, as for assignment, if either type is 'id' 3962 // allow silent coercion. Finally, if the types are 3963 // incompatible then make sure to use 'id' as the composite 3964 // type so the result is acceptable for sending messages to. 3965 3966 // FIXME: Consider unifying with 'areComparableObjCPointerTypes'. 3967 // It could return the composite type. 3968 if (Context.canAssignObjCInterfaces(LHSOPT, RHSOPT)) { 3969 compositeType = RHSOPT->isObjCBuiltinType() ? RHSTy : LHSTy; 3970 } else if (Context.canAssignObjCInterfaces(RHSOPT, LHSOPT)) { 3971 compositeType = LHSOPT->isObjCBuiltinType() ? LHSTy : RHSTy; 3972 } else if ((LHSTy->isObjCQualifiedIdType() || 3973 RHSTy->isObjCQualifiedIdType()) && 3974 Context.ObjCQualifiedIdTypesAreCompatible(LHSTy, RHSTy, true)) { 3975 // Need to handle "id<xx>" explicitly. 3976 // GCC allows qualified id and any Objective-C type to devolve to 3977 // id. Currently localizing to here until clear this should be 3978 // part of ObjCQualifiedIdTypesAreCompatible. 3979 compositeType = Context.getObjCIdType(); 3980 } else if (LHSTy->isObjCIdType() || RHSTy->isObjCIdType()) { 3981 compositeType = Context.getObjCIdType(); 3982 } else if (!(compositeType = 3983 Context.areCommonBaseCompatible(LHSOPT, RHSOPT)).isNull()) 3984 ; 3985 else { 3986 Diag(QuestionLoc, diag::ext_typecheck_cond_incompatible_operands) 3987 << LHSTy << RHSTy 3988 << LHS->getSourceRange() << RHS->getSourceRange(); 3989 QualType incompatTy = Context.getObjCIdType(); 3990 ImpCastExprToType(LHS, incompatTy, CastExpr::CK_BitCast); 3991 ImpCastExprToType(RHS, incompatTy, CastExpr::CK_BitCast); 3992 return incompatTy; 3993 } 3994 // The object pointer types are compatible. 3995 ImpCastExprToType(LHS, compositeType, CastExpr::CK_BitCast); 3996 ImpCastExprToType(RHS, compositeType, CastExpr::CK_BitCast); 3997 return compositeType; 3998 } 3999 // Check Objective-C object pointer types and 'void *' 4000 if (LHSTy->isVoidPointerType() && RHSTy->isObjCObjectPointerType()) { 4001 QualType lhptee = LHSTy->getAs<PointerType>()->getPointeeType(); 4002 QualType rhptee = RHSTy->getAs<ObjCObjectPointerType>()->getPointeeType(); 4003 QualType destPointee 4004 = Context.getQualifiedType(lhptee, rhptee.getQualifiers()); 4005 QualType destType = Context.getPointerType(destPointee); 4006 // Add qualifiers if necessary. 4007 ImpCastExprToType(LHS, destType, CastExpr::CK_NoOp); 4008 // Promote to void*. 4009 ImpCastExprToType(RHS, destType, CastExpr::CK_BitCast); 4010 return destType; 4011 } 4012 if (LHSTy->isObjCObjectPointerType() && RHSTy->isVoidPointerType()) { 4013 QualType lhptee = LHSTy->getAs<ObjCObjectPointerType>()->getPointeeType(); 4014 QualType rhptee = RHSTy->getAs<PointerType>()->getPointeeType(); 4015 QualType destPointee 4016 = Context.getQualifiedType(rhptee, lhptee.getQualifiers()); 4017 QualType destType = Context.getPointerType(destPointee); 4018 // Add qualifiers if necessary. 4019 ImpCastExprToType(RHS, destType, CastExpr::CK_NoOp); 4020 // Promote to void*. 4021 ImpCastExprToType(LHS, destType, CastExpr::CK_BitCast); 4022 return destType; 4023 } 4024 // Check constraints for C object pointers types (C99 6.5.15p3,6). 4025 if (LHSTy->isPointerType() && RHSTy->isPointerType()) { 4026 // get the "pointed to" types 4027 QualType lhptee = LHSTy->getAs<PointerType>()->getPointeeType(); 4028 QualType rhptee = RHSTy->getAs<PointerType>()->getPointeeType(); 4029 4030 // ignore qualifiers on void (C99 6.5.15p3, clause 6) 4031 if (lhptee->isVoidType() && rhptee->isIncompleteOrObjectType()) { 4032 // Figure out necessary qualifiers (C99 6.5.15p6) 4033 QualType destPointee 4034 = Context.getQualifiedType(lhptee, rhptee.getQualifiers()); 4035 QualType destType = Context.getPointerType(destPointee); 4036 // Add qualifiers if necessary. 4037 ImpCastExprToType(LHS, destType, CastExpr::CK_NoOp); 4038 // Promote to void*. 4039 ImpCastExprToType(RHS, destType, CastExpr::CK_BitCast); 4040 return destType; 4041 } 4042 if (rhptee->isVoidType() && lhptee->isIncompleteOrObjectType()) { 4043 QualType destPointee 4044 = Context.getQualifiedType(rhptee, lhptee.getQualifiers()); 4045 QualType destType = Context.getPointerType(destPointee); 4046 // Add qualifiers if necessary. 4047 ImpCastExprToType(RHS, destType, CastExpr::CK_NoOp); 4048 // Promote to void*. 4049 ImpCastExprToType(LHS, destType, CastExpr::CK_BitCast); 4050 return destType; 4051 } 4052 4053 if (Context.getCanonicalType(LHSTy) == Context.getCanonicalType(RHSTy)) { 4054 // Two identical pointer types are always compatible. 4055 return LHSTy; 4056 } 4057 if (!Context.typesAreCompatible(lhptee.getUnqualifiedType(), 4058 rhptee.getUnqualifiedType())) { 4059 Diag(QuestionLoc, diag::warn_typecheck_cond_incompatible_pointers) 4060 << LHSTy << RHSTy << LHS->getSourceRange() << RHS->getSourceRange(); 4061 // In this situation, we assume void* type. No especially good 4062 // reason, but this is what gcc does, and we do have to pick 4063 // to get a consistent AST. 4064 QualType incompatTy = Context.getPointerType(Context.VoidTy); 4065 ImpCastExprToType(LHS, incompatTy, CastExpr::CK_BitCast); 4066 ImpCastExprToType(RHS, incompatTy, CastExpr::CK_BitCast); 4067 return incompatTy; 4068 } 4069 // The pointer types are compatible. 4070 // C99 6.5.15p6: If both operands are pointers to compatible types *or* to 4071 // differently qualified versions of compatible types, the result type is 4072 // a pointer to an appropriately qualified version of the *composite* 4073 // type. 4074 // FIXME: Need to calculate the composite type. 4075 // FIXME: Need to add qualifiers 4076 ImpCastExprToType(LHS, LHSTy, CastExpr::CK_BitCast); 4077 ImpCastExprToType(RHS, LHSTy, CastExpr::CK_BitCast); 4078 return LHSTy; 4079 } 4080 4081 // GCC compatibility: soften pointer/integer mismatch. 4082 if (RHSTy->isPointerType() && LHSTy->isIntegerType()) { 4083 Diag(QuestionLoc, diag::warn_typecheck_cond_pointer_integer_mismatch) 4084 << LHSTy << RHSTy << LHS->getSourceRange() << RHS->getSourceRange(); 4085 ImpCastExprToType(LHS, RHSTy, CastExpr::CK_IntegralToPointer); 4086 return RHSTy; 4087 } 4088 if (LHSTy->isPointerType() && RHSTy->isIntegerType()) { 4089 Diag(QuestionLoc, diag::warn_typecheck_cond_pointer_integer_mismatch) 4090 << LHSTy << RHSTy << LHS->getSourceRange() << RHS->getSourceRange(); 4091 ImpCastExprToType(RHS, LHSTy, CastExpr::CK_IntegralToPointer); 4092 return LHSTy; 4093 } 4094 4095 // Otherwise, the operands are not compatible. 4096 Diag(QuestionLoc, diag::err_typecheck_cond_incompatible_operands) 4097 << LHSTy << RHSTy << LHS->getSourceRange() << RHS->getSourceRange(); 4098 return QualType(); 4099} 4100 4101/// ActOnConditionalOp - Parse a ?: operation. Note that 'LHS' may be null 4102/// in the case of a the GNU conditional expr extension. 4103Action::OwningExprResult Sema::ActOnConditionalOp(SourceLocation QuestionLoc, 4104 SourceLocation ColonLoc, 4105 ExprArg Cond, ExprArg LHS, 4106 ExprArg RHS) { 4107 Expr *CondExpr = (Expr *) Cond.get(); 4108 Expr *LHSExpr = (Expr *) LHS.get(), *RHSExpr = (Expr *) RHS.get(); 4109 4110 // If this is the gnu "x ?: y" extension, analyze the types as though the LHS 4111 // was the condition. 4112 bool isLHSNull = LHSExpr == 0; 4113 if (isLHSNull) 4114 LHSExpr = CondExpr; 4115 4116 QualType result = CheckConditionalOperands(CondExpr, LHSExpr, 4117 RHSExpr, QuestionLoc); 4118 if (result.isNull()) 4119 return ExprError(); 4120 4121 Cond.release(); 4122 LHS.release(); 4123 RHS.release(); 4124 return Owned(new (Context) ConditionalOperator(CondExpr, QuestionLoc, 4125 isLHSNull ? 0 : LHSExpr, 4126 ColonLoc, RHSExpr, result)); 4127} 4128 4129// CheckPointerTypesForAssignment - This is a very tricky routine (despite 4130// being closely modeled after the C99 spec:-). The odd characteristic of this 4131// routine is it effectively iqnores the qualifiers on the top level pointee. 4132// This circumvents the usual type rules specified in 6.2.7p1 & 6.7.5.[1-3]. 4133// FIXME: add a couple examples in this comment. 4134Sema::AssignConvertType 4135Sema::CheckPointerTypesForAssignment(QualType lhsType, QualType rhsType) { 4136 QualType lhptee, rhptee; 4137 4138 if ((lhsType->isObjCClassType() && 4139 (rhsType.getDesugaredType() == Context.ObjCClassRedefinitionType)) || 4140 (rhsType->isObjCClassType() && 4141 (lhsType.getDesugaredType() == Context.ObjCClassRedefinitionType))) { 4142 return Compatible; 4143 } 4144 4145 // get the "pointed to" type (ignoring qualifiers at the top level) 4146 lhptee = lhsType->getAs<PointerType>()->getPointeeType(); 4147 rhptee = rhsType->getAs<PointerType>()->getPointeeType(); 4148 4149 // make sure we operate on the canonical type 4150 lhptee = Context.getCanonicalType(lhptee); 4151 rhptee = Context.getCanonicalType(rhptee); 4152 4153 AssignConvertType ConvTy = Compatible; 4154 4155 // C99 6.5.16.1p1: This following citation is common to constraints 4156 // 3 & 4 (below). ...and the type *pointed to* by the left has all the 4157 // qualifiers of the type *pointed to* by the right; 4158 // FIXME: Handle ExtQualType 4159 if (!lhptee.isAtLeastAsQualifiedAs(rhptee)) 4160 ConvTy = CompatiblePointerDiscardsQualifiers; 4161 4162 // C99 6.5.16.1p1 (constraint 4): If one operand is a pointer to an object or 4163 // incomplete type and the other is a pointer to a qualified or unqualified 4164 // version of void... 4165 if (lhptee->isVoidType()) { 4166 if (rhptee->isIncompleteOrObjectType()) 4167 return ConvTy; 4168 4169 // As an extension, we allow cast to/from void* to function pointer. 4170 assert(rhptee->isFunctionType()); 4171 return FunctionVoidPointer; 4172 } 4173 4174 if (rhptee->isVoidType()) { 4175 if (lhptee->isIncompleteOrObjectType()) 4176 return ConvTy; 4177 4178 // As an extension, we allow cast to/from void* to function pointer. 4179 assert(lhptee->isFunctionType()); 4180 return FunctionVoidPointer; 4181 } 4182 // C99 6.5.16.1p1 (constraint 3): both operands are pointers to qualified or 4183 // unqualified versions of compatible types, ... 4184 lhptee = lhptee.getUnqualifiedType(); 4185 rhptee = rhptee.getUnqualifiedType(); 4186 if (!Context.typesAreCompatible(lhptee, rhptee)) { 4187 // Check if the pointee types are compatible ignoring the sign. 4188 // We explicitly check for char so that we catch "char" vs 4189 // "unsigned char" on systems where "char" is unsigned. 4190 if (lhptee->isCharType()) 4191 lhptee = Context.UnsignedCharTy; 4192 else if (lhptee->isSignedIntegerType()) 4193 lhptee = Context.getCorrespondingUnsignedType(lhptee); 4194 4195 if (rhptee->isCharType()) 4196 rhptee = Context.UnsignedCharTy; 4197 else if (rhptee->isSignedIntegerType()) 4198 rhptee = Context.getCorrespondingUnsignedType(rhptee); 4199 4200 if (lhptee == rhptee) { 4201 // Types are compatible ignoring the sign. Qualifier incompatibility 4202 // takes priority over sign incompatibility because the sign 4203 // warning can be disabled. 4204 if (ConvTy != Compatible) 4205 return ConvTy; 4206 return IncompatiblePointerSign; 4207 } 4208 4209 // If we are a multi-level pointer, it's possible that our issue is simply 4210 // one of qualification - e.g. char ** -> const char ** is not allowed. If 4211 // the eventual target type is the same and the pointers have the same 4212 // level of indirection, this must be the issue. 4213 if (lhptee->isPointerType() && rhptee->isPointerType()) { 4214 do { 4215 lhptee = lhptee->getAs<PointerType>()->getPointeeType(); 4216 rhptee = rhptee->getAs<PointerType>()->getPointeeType(); 4217 4218 lhptee = Context.getCanonicalType(lhptee); 4219 rhptee = Context.getCanonicalType(rhptee); 4220 } while (lhptee->isPointerType() && rhptee->isPointerType()); 4221 4222 if (Context.hasSameUnqualifiedType(lhptee, rhptee)) 4223 return IncompatibleNestedPointerQualifiers; 4224 } 4225 4226 // General pointer incompatibility takes priority over qualifiers. 4227 return IncompatiblePointer; 4228 } 4229 return ConvTy; 4230} 4231 4232/// CheckBlockPointerTypesForAssignment - This routine determines whether two 4233/// block pointer types are compatible or whether a block and normal pointer 4234/// are compatible. It is more restrict than comparing two function pointer 4235// types. 4236Sema::AssignConvertType 4237Sema::CheckBlockPointerTypesForAssignment(QualType lhsType, 4238 QualType rhsType) { 4239 QualType lhptee, rhptee; 4240 4241 // get the "pointed to" type (ignoring qualifiers at the top level) 4242 lhptee = lhsType->getAs<BlockPointerType>()->getPointeeType(); 4243 rhptee = rhsType->getAs<BlockPointerType>()->getPointeeType(); 4244 4245 // make sure we operate on the canonical type 4246 lhptee = Context.getCanonicalType(lhptee); 4247 rhptee = Context.getCanonicalType(rhptee); 4248 4249 AssignConvertType ConvTy = Compatible; 4250 4251 // For blocks we enforce that qualifiers are identical. 4252 if (lhptee.getLocalCVRQualifiers() != rhptee.getLocalCVRQualifiers()) 4253 ConvTy = CompatiblePointerDiscardsQualifiers; 4254 4255 if (!Context.typesAreCompatible(lhptee, rhptee)) 4256 return IncompatibleBlockPointer; 4257 return ConvTy; 4258} 4259 4260/// CheckAssignmentConstraints (C99 6.5.16) - This routine currently 4261/// has code to accommodate several GCC extensions when type checking 4262/// pointers. Here are some objectionable examples that GCC considers warnings: 4263/// 4264/// int a, *pint; 4265/// short *pshort; 4266/// struct foo *pfoo; 4267/// 4268/// pint = pshort; // warning: assignment from incompatible pointer type 4269/// a = pint; // warning: assignment makes integer from pointer without a cast 4270/// pint = a; // warning: assignment makes pointer from integer without a cast 4271/// pint = pfoo; // warning: assignment from incompatible pointer type 4272/// 4273/// As a result, the code for dealing with pointers is more complex than the 4274/// C99 spec dictates. 4275/// 4276Sema::AssignConvertType 4277Sema::CheckAssignmentConstraints(QualType lhsType, QualType rhsType) { 4278 // Get canonical types. We're not formatting these types, just comparing 4279 // them. 4280 lhsType = Context.getCanonicalType(lhsType).getUnqualifiedType(); 4281 rhsType = Context.getCanonicalType(rhsType).getUnqualifiedType(); 4282 4283 if (lhsType == rhsType) 4284 return Compatible; // Common case: fast path an exact match. 4285 4286 if ((lhsType->isObjCClassType() && 4287 (rhsType.getDesugaredType() == Context.ObjCClassRedefinitionType)) || 4288 (rhsType->isObjCClassType() && 4289 (lhsType.getDesugaredType() == Context.ObjCClassRedefinitionType))) { 4290 return Compatible; 4291 } 4292 4293 // If the left-hand side is a reference type, then we are in a 4294 // (rare!) case where we've allowed the use of references in C, 4295 // e.g., as a parameter type in a built-in function. In this case, 4296 // just make sure that the type referenced is compatible with the 4297 // right-hand side type. The caller is responsible for adjusting 4298 // lhsType so that the resulting expression does not have reference 4299 // type. 4300 if (const ReferenceType *lhsTypeRef = lhsType->getAs<ReferenceType>()) { 4301 if (Context.typesAreCompatible(lhsTypeRef->getPointeeType(), rhsType)) 4302 return Compatible; 4303 return Incompatible; 4304 } 4305 // Allow scalar to ExtVector assignments, and assignments of an ExtVector type 4306 // to the same ExtVector type. 4307 if (lhsType->isExtVectorType()) { 4308 if (rhsType->isExtVectorType()) 4309 return lhsType == rhsType ? Compatible : Incompatible; 4310 if (!rhsType->isVectorType() && rhsType->isArithmeticType()) 4311 return Compatible; 4312 } 4313 4314 if (lhsType->isVectorType() || rhsType->isVectorType()) { 4315 // If we are allowing lax vector conversions, and LHS and RHS are both 4316 // vectors, the total size only needs to be the same. This is a bitcast; 4317 // no bits are changed but the result type is different. 4318 if (getLangOptions().LaxVectorConversions && 4319 lhsType->isVectorType() && rhsType->isVectorType()) { 4320 if (Context.getTypeSize(lhsType) == Context.getTypeSize(rhsType)) 4321 return IncompatibleVectors; 4322 } 4323 return Incompatible; 4324 } 4325 4326 if (lhsType->isArithmeticType() && rhsType->isArithmeticType()) 4327 return Compatible; 4328 4329 if (isa<PointerType>(lhsType)) { 4330 if (rhsType->isIntegerType()) 4331 return IntToPointer; 4332 4333 if (isa<PointerType>(rhsType)) 4334 return CheckPointerTypesForAssignment(lhsType, rhsType); 4335 4336 // In general, C pointers are not compatible with ObjC object pointers. 4337 if (isa<ObjCObjectPointerType>(rhsType)) { 4338 if (lhsType->isVoidPointerType()) // an exception to the rule. 4339 return Compatible; 4340 return IncompatiblePointer; 4341 } 4342 if (rhsType->getAs<BlockPointerType>()) { 4343 if (lhsType->getAs<PointerType>()->getPointeeType()->isVoidType()) 4344 return Compatible; 4345 4346 // Treat block pointers as objects. 4347 if (getLangOptions().ObjC1 && lhsType->isObjCIdType()) 4348 return Compatible; 4349 } 4350 return Incompatible; 4351 } 4352 4353 if (isa<BlockPointerType>(lhsType)) { 4354 if (rhsType->isIntegerType()) 4355 return IntToBlockPointer; 4356 4357 // Treat block pointers as objects. 4358 if (getLangOptions().ObjC1 && rhsType->isObjCIdType()) 4359 return Compatible; 4360 4361 if (rhsType->isBlockPointerType()) 4362 return CheckBlockPointerTypesForAssignment(lhsType, rhsType); 4363 4364 if (const PointerType *RHSPT = rhsType->getAs<PointerType>()) { 4365 if (RHSPT->getPointeeType()->isVoidType()) 4366 return Compatible; 4367 } 4368 return Incompatible; 4369 } 4370 4371 if (isa<ObjCObjectPointerType>(lhsType)) { 4372 if (rhsType->isIntegerType()) 4373 return IntToPointer; 4374 4375 // In general, C pointers are not compatible with ObjC object pointers. 4376 if (isa<PointerType>(rhsType)) { 4377 if (rhsType->isVoidPointerType()) // an exception to the rule. 4378 return Compatible; 4379 return IncompatiblePointer; 4380 } 4381 if (rhsType->isObjCObjectPointerType()) { 4382 if (lhsType->isObjCBuiltinType() || rhsType->isObjCBuiltinType()) 4383 return Compatible; 4384 if (Context.typesAreCompatible(lhsType, rhsType)) 4385 return Compatible; 4386 if (lhsType->isObjCQualifiedIdType() || rhsType->isObjCQualifiedIdType()) 4387 return IncompatibleObjCQualifiedId; 4388 return IncompatiblePointer; 4389 } 4390 if (const PointerType *RHSPT = rhsType->getAs<PointerType>()) { 4391 if (RHSPT->getPointeeType()->isVoidType()) 4392 return Compatible; 4393 } 4394 // Treat block pointers as objects. 4395 if (rhsType->isBlockPointerType()) 4396 return Compatible; 4397 return Incompatible; 4398 } 4399 if (isa<PointerType>(rhsType)) { 4400 // C99 6.5.16.1p1: the left operand is _Bool and the right is a pointer. 4401 if (lhsType == Context.BoolTy) 4402 return Compatible; 4403 4404 if (lhsType->isIntegerType()) 4405 return PointerToInt; 4406 4407 if (isa<PointerType>(lhsType)) 4408 return CheckPointerTypesForAssignment(lhsType, rhsType); 4409 4410 if (isa<BlockPointerType>(lhsType) && 4411 rhsType->getAs<PointerType>()->getPointeeType()->isVoidType()) 4412 return Compatible; 4413 return Incompatible; 4414 } 4415 if (isa<ObjCObjectPointerType>(rhsType)) { 4416 // C99 6.5.16.1p1: the left operand is _Bool and the right is a pointer. 4417 if (lhsType == Context.BoolTy) 4418 return Compatible; 4419 4420 if (lhsType->isIntegerType()) 4421 return PointerToInt; 4422 4423 // In general, C pointers are not compatible with ObjC object pointers. 4424 if (isa<PointerType>(lhsType)) { 4425 if (lhsType->isVoidPointerType()) // an exception to the rule. 4426 return Compatible; 4427 return IncompatiblePointer; 4428 } 4429 if (isa<BlockPointerType>(lhsType) && 4430 rhsType->getAs<PointerType>()->getPointeeType()->isVoidType()) 4431 return Compatible; 4432 return Incompatible; 4433 } 4434 4435 if (isa<TagType>(lhsType) && isa<TagType>(rhsType)) { 4436 if (Context.typesAreCompatible(lhsType, rhsType)) 4437 return Compatible; 4438 } 4439 return Incompatible; 4440} 4441 4442/// \brief Constructs a transparent union from an expression that is 4443/// used to initialize the transparent union. 4444static void ConstructTransparentUnion(ASTContext &C, Expr *&E, 4445 QualType UnionType, FieldDecl *Field) { 4446 // Build an initializer list that designates the appropriate member 4447 // of the transparent union. 4448 InitListExpr *Initializer = new (C) InitListExpr(SourceLocation(), 4449 &E, 1, 4450 SourceLocation()); 4451 Initializer->setType(UnionType); 4452 Initializer->setInitializedFieldInUnion(Field); 4453 4454 // Build a compound literal constructing a value of the transparent 4455 // union type from this initializer list. 4456 E = new (C) CompoundLiteralExpr(SourceLocation(), UnionType, Initializer, 4457 false); 4458} 4459 4460Sema::AssignConvertType 4461Sema::CheckTransparentUnionArgumentConstraints(QualType ArgType, Expr *&rExpr) { 4462 QualType FromType = rExpr->getType(); 4463 4464 // If the ArgType is a Union type, we want to handle a potential 4465 // transparent_union GCC extension. 4466 const RecordType *UT = ArgType->getAsUnionType(); 4467 if (!UT || !UT->getDecl()->hasAttr<TransparentUnionAttr>()) 4468 return Incompatible; 4469 4470 // The field to initialize within the transparent union. 4471 RecordDecl *UD = UT->getDecl(); 4472 FieldDecl *InitField = 0; 4473 // It's compatible if the expression matches any of the fields. 4474 for (RecordDecl::field_iterator it = UD->field_begin(), 4475 itend = UD->field_end(); 4476 it != itend; ++it) { 4477 if (it->getType()->isPointerType()) { 4478 // If the transparent union contains a pointer type, we allow: 4479 // 1) void pointer 4480 // 2) null pointer constant 4481 if (FromType->isPointerType()) 4482 if (FromType->getAs<PointerType>()->getPointeeType()->isVoidType()) { 4483 ImpCastExprToType(rExpr, it->getType(), CastExpr::CK_BitCast); 4484 InitField = *it; 4485 break; 4486 } 4487 4488 if (rExpr->isNullPointerConstant(Context, 4489 Expr::NPC_ValueDependentIsNull)) { 4490 ImpCastExprToType(rExpr, it->getType(), CastExpr::CK_IntegralToPointer); 4491 InitField = *it; 4492 break; 4493 } 4494 } 4495 4496 if (CheckAssignmentConstraints(it->getType(), rExpr->getType()) 4497 == Compatible) { 4498 InitField = *it; 4499 break; 4500 } 4501 } 4502 4503 if (!InitField) 4504 return Incompatible; 4505 4506 ConstructTransparentUnion(Context, rExpr, ArgType, InitField); 4507 return Compatible; 4508} 4509 4510Sema::AssignConvertType 4511Sema::CheckSingleAssignmentConstraints(QualType lhsType, Expr *&rExpr) { 4512 if (getLangOptions().CPlusPlus) { 4513 if (!lhsType->isRecordType()) { 4514 // C++ 5.17p3: If the left operand is not of class type, the 4515 // expression is implicitly converted (C++ 4) to the 4516 // cv-unqualified type of the left operand. 4517 if (PerformImplicitConversion(rExpr, lhsType.getUnqualifiedType(), 4518 "assigning")) 4519 return Incompatible; 4520 return Compatible; 4521 } 4522 4523 // FIXME: Currently, we fall through and treat C++ classes like C 4524 // structures. 4525 } 4526 4527 // C99 6.5.16.1p1: the left operand is a pointer and the right is 4528 // a null pointer constant. 4529 if ((lhsType->isPointerType() || 4530 lhsType->isObjCObjectPointerType() || 4531 lhsType->isBlockPointerType()) 4532 && rExpr->isNullPointerConstant(Context, 4533 Expr::NPC_ValueDependentIsNull)) { 4534 ImpCastExprToType(rExpr, lhsType, CastExpr::CK_Unknown); 4535 return Compatible; 4536 } 4537 4538 // This check seems unnatural, however it is necessary to ensure the proper 4539 // conversion of functions/arrays. If the conversion were done for all 4540 // DeclExpr's (created by ActOnIdExpression), it would mess up the unary 4541 // expressions that surpress this implicit conversion (&, sizeof). 4542 // 4543 // Suppress this for references: C++ 8.5.3p5. 4544 if (!lhsType->isReferenceType()) 4545 DefaultFunctionArrayConversion(rExpr); 4546 4547 Sema::AssignConvertType result = 4548 CheckAssignmentConstraints(lhsType, rExpr->getType()); 4549 4550 // C99 6.5.16.1p2: The value of the right operand is converted to the 4551 // type of the assignment expression. 4552 // CheckAssignmentConstraints allows the left-hand side to be a reference, 4553 // so that we can use references in built-in functions even in C. 4554 // The getNonReferenceType() call makes sure that the resulting expression 4555 // does not have reference type. 4556 if (result != Incompatible && rExpr->getType() != lhsType) 4557 ImpCastExprToType(rExpr, lhsType.getNonReferenceType(), 4558 CastExpr::CK_Unknown); 4559 return result; 4560} 4561 4562QualType Sema::InvalidOperands(SourceLocation Loc, Expr *&lex, Expr *&rex) { 4563 Diag(Loc, diag::err_typecheck_invalid_operands) 4564 << lex->getType() << rex->getType() 4565 << lex->getSourceRange() << rex->getSourceRange(); 4566 return QualType(); 4567} 4568 4569inline QualType Sema::CheckVectorOperands(SourceLocation Loc, Expr *&lex, 4570 Expr *&rex) { 4571 // For conversion purposes, we ignore any qualifiers. 4572 // For example, "const float" and "float" are equivalent. 4573 QualType lhsType = 4574 Context.getCanonicalType(lex->getType()).getUnqualifiedType(); 4575 QualType rhsType = 4576 Context.getCanonicalType(rex->getType()).getUnqualifiedType(); 4577 4578 // If the vector types are identical, return. 4579 if (lhsType == rhsType) 4580 return lhsType; 4581 4582 // Handle the case of a vector & extvector type of the same size and element 4583 // type. It would be nice if we only had one vector type someday. 4584 if (getLangOptions().LaxVectorConversions) { 4585 // FIXME: Should we warn here? 4586 if (const VectorType *LV = lhsType->getAs<VectorType>()) { 4587 if (const VectorType *RV = rhsType->getAs<VectorType>()) 4588 if (LV->getElementType() == RV->getElementType() && 4589 LV->getNumElements() == RV->getNumElements()) { 4590 return lhsType->isExtVectorType() ? lhsType : rhsType; 4591 } 4592 } 4593 } 4594 4595 // Canonicalize the ExtVector to the LHS, remember if we swapped so we can 4596 // swap back (so that we don't reverse the inputs to a subtract, for instance. 4597 bool swapped = false; 4598 if (rhsType->isExtVectorType()) { 4599 swapped = true; 4600 std::swap(rex, lex); 4601 std::swap(rhsType, lhsType); 4602 } 4603 4604 // Handle the case of an ext vector and scalar. 4605 if (const ExtVectorType *LV = lhsType->getAs<ExtVectorType>()) { 4606 QualType EltTy = LV->getElementType(); 4607 if (EltTy->isIntegralType() && rhsType->isIntegralType()) { 4608 if (Context.getIntegerTypeOrder(EltTy, rhsType) >= 0) { 4609 ImpCastExprToType(rex, lhsType, CastExpr::CK_IntegralCast); 4610 if (swapped) std::swap(rex, lex); 4611 return lhsType; 4612 } 4613 } 4614 if (EltTy->isRealFloatingType() && rhsType->isScalarType() && 4615 rhsType->isRealFloatingType()) { 4616 if (Context.getFloatingTypeOrder(EltTy, rhsType) >= 0) { 4617 ImpCastExprToType(rex, lhsType, CastExpr::CK_FloatingCast); 4618 if (swapped) std::swap(rex, lex); 4619 return lhsType; 4620 } 4621 } 4622 } 4623 4624 // Vectors of different size or scalar and non-ext-vector are errors. 4625 Diag(Loc, diag::err_typecheck_vector_not_convertable) 4626 << lex->getType() << rex->getType() 4627 << lex->getSourceRange() << rex->getSourceRange(); 4628 return QualType(); 4629} 4630 4631inline QualType Sema::CheckMultiplyDivideOperands( 4632 Expr *&lex, Expr *&rex, SourceLocation Loc, bool isCompAssign) { 4633 if (lex->getType()->isVectorType() || rex->getType()->isVectorType()) 4634 return CheckVectorOperands(Loc, lex, rex); 4635 4636 QualType compType = UsualArithmeticConversions(lex, rex, isCompAssign); 4637 4638 if (lex->getType()->isArithmeticType() && rex->getType()->isArithmeticType()) 4639 return compType; 4640 return InvalidOperands(Loc, lex, rex); 4641} 4642 4643inline QualType Sema::CheckRemainderOperands( 4644 Expr *&lex, Expr *&rex, SourceLocation Loc, bool isCompAssign) { 4645 if (lex->getType()->isVectorType() || rex->getType()->isVectorType()) { 4646 if (lex->getType()->isIntegerType() && rex->getType()->isIntegerType()) 4647 return CheckVectorOperands(Loc, lex, rex); 4648 return InvalidOperands(Loc, lex, rex); 4649 } 4650 4651 QualType compType = UsualArithmeticConversions(lex, rex, isCompAssign); 4652 4653 if (lex->getType()->isIntegerType() && rex->getType()->isIntegerType()) 4654 return compType; 4655 return InvalidOperands(Loc, lex, rex); 4656} 4657 4658inline QualType Sema::CheckAdditionOperands( // C99 6.5.6 4659 Expr *&lex, Expr *&rex, SourceLocation Loc, QualType* CompLHSTy) { 4660 if (lex->getType()->isVectorType() || rex->getType()->isVectorType()) { 4661 QualType compType = CheckVectorOperands(Loc, lex, rex); 4662 if (CompLHSTy) *CompLHSTy = compType; 4663 return compType; 4664 } 4665 4666 QualType compType = UsualArithmeticConversions(lex, rex, CompLHSTy); 4667 4668 // handle the common case first (both operands are arithmetic). 4669 if (lex->getType()->isArithmeticType() && 4670 rex->getType()->isArithmeticType()) { 4671 if (CompLHSTy) *CompLHSTy = compType; 4672 return compType; 4673 } 4674 4675 // Put any potential pointer into PExp 4676 Expr* PExp = lex, *IExp = rex; 4677 if (IExp->getType()->isAnyPointerType()) 4678 std::swap(PExp, IExp); 4679 4680 if (PExp->getType()->isAnyPointerType()) { 4681 4682 if (IExp->getType()->isIntegerType()) { 4683 QualType PointeeTy = PExp->getType()->getPointeeType(); 4684 4685 // Check for arithmetic on pointers to incomplete types. 4686 if (PointeeTy->isVoidType()) { 4687 if (getLangOptions().CPlusPlus) { 4688 Diag(Loc, diag::err_typecheck_pointer_arith_void_type) 4689 << lex->getSourceRange() << rex->getSourceRange(); 4690 return QualType(); 4691 } 4692 4693 // GNU extension: arithmetic on pointer to void 4694 Diag(Loc, diag::ext_gnu_void_ptr) 4695 << lex->getSourceRange() << rex->getSourceRange(); 4696 } else if (PointeeTy->isFunctionType()) { 4697 if (getLangOptions().CPlusPlus) { 4698 Diag(Loc, diag::err_typecheck_pointer_arith_function_type) 4699 << lex->getType() << lex->getSourceRange(); 4700 return QualType(); 4701 } 4702 4703 // GNU extension: arithmetic on pointer to function 4704 Diag(Loc, diag::ext_gnu_ptr_func_arith) 4705 << lex->getType() << lex->getSourceRange(); 4706 } else { 4707 // Check if we require a complete type. 4708 if (((PExp->getType()->isPointerType() && 4709 !PExp->getType()->isDependentType()) || 4710 PExp->getType()->isObjCObjectPointerType()) && 4711 RequireCompleteType(Loc, PointeeTy, 4712 PDiag(diag::err_typecheck_arithmetic_incomplete_type) 4713 << PExp->getSourceRange() 4714 << PExp->getType())) 4715 return QualType(); 4716 } 4717 // Diagnose bad cases where we step over interface counts. 4718 if (PointeeTy->isObjCInterfaceType() && LangOpts.ObjCNonFragileABI) { 4719 Diag(Loc, diag::err_arithmetic_nonfragile_interface) 4720 << PointeeTy << PExp->getSourceRange(); 4721 return QualType(); 4722 } 4723 4724 if (CompLHSTy) { 4725 QualType LHSTy = Context.isPromotableBitField(lex); 4726 if (LHSTy.isNull()) { 4727 LHSTy = lex->getType(); 4728 if (LHSTy->isPromotableIntegerType()) 4729 LHSTy = Context.getPromotedIntegerType(LHSTy); 4730 } 4731 *CompLHSTy = LHSTy; 4732 } 4733 return PExp->getType(); 4734 } 4735 } 4736 4737 return InvalidOperands(Loc, lex, rex); 4738} 4739 4740// C99 6.5.6 4741QualType Sema::CheckSubtractionOperands(Expr *&lex, Expr *&rex, 4742 SourceLocation Loc, QualType* CompLHSTy) { 4743 if (lex->getType()->isVectorType() || rex->getType()->isVectorType()) { 4744 QualType compType = CheckVectorOperands(Loc, lex, rex); 4745 if (CompLHSTy) *CompLHSTy = compType; 4746 return compType; 4747 } 4748 4749 QualType compType = UsualArithmeticConversions(lex, rex, CompLHSTy); 4750 4751 // Enforce type constraints: C99 6.5.6p3. 4752 4753 // Handle the common case first (both operands are arithmetic). 4754 if (lex->getType()->isArithmeticType() 4755 && rex->getType()->isArithmeticType()) { 4756 if (CompLHSTy) *CompLHSTy = compType; 4757 return compType; 4758 } 4759 4760 // Either ptr - int or ptr - ptr. 4761 if (lex->getType()->isAnyPointerType()) { 4762 QualType lpointee = lex->getType()->getPointeeType(); 4763 4764 // The LHS must be an completely-defined object type. 4765 4766 bool ComplainAboutVoid = false; 4767 Expr *ComplainAboutFunc = 0; 4768 if (lpointee->isVoidType()) { 4769 if (getLangOptions().CPlusPlus) { 4770 Diag(Loc, diag::err_typecheck_pointer_arith_void_type) 4771 << lex->getSourceRange() << rex->getSourceRange(); 4772 return QualType(); 4773 } 4774 4775 // GNU C extension: arithmetic on pointer to void 4776 ComplainAboutVoid = true; 4777 } else if (lpointee->isFunctionType()) { 4778 if (getLangOptions().CPlusPlus) { 4779 Diag(Loc, diag::err_typecheck_pointer_arith_function_type) 4780 << lex->getType() << lex->getSourceRange(); 4781 return QualType(); 4782 } 4783 4784 // GNU C extension: arithmetic on pointer to function 4785 ComplainAboutFunc = lex; 4786 } else if (!lpointee->isDependentType() && 4787 RequireCompleteType(Loc, lpointee, 4788 PDiag(diag::err_typecheck_sub_ptr_object) 4789 << lex->getSourceRange() 4790 << lex->getType())) 4791 return QualType(); 4792 4793 // Diagnose bad cases where we step over interface counts. 4794 if (lpointee->isObjCInterfaceType() && LangOpts.ObjCNonFragileABI) { 4795 Diag(Loc, diag::err_arithmetic_nonfragile_interface) 4796 << lpointee << lex->getSourceRange(); 4797 return QualType(); 4798 } 4799 4800 // The result type of a pointer-int computation is the pointer type. 4801 if (rex->getType()->isIntegerType()) { 4802 if (ComplainAboutVoid) 4803 Diag(Loc, diag::ext_gnu_void_ptr) 4804 << lex->getSourceRange() << rex->getSourceRange(); 4805 if (ComplainAboutFunc) 4806 Diag(Loc, diag::ext_gnu_ptr_func_arith) 4807 << ComplainAboutFunc->getType() 4808 << ComplainAboutFunc->getSourceRange(); 4809 4810 if (CompLHSTy) *CompLHSTy = lex->getType(); 4811 return lex->getType(); 4812 } 4813 4814 // Handle pointer-pointer subtractions. 4815 if (const PointerType *RHSPTy = rex->getType()->getAs<PointerType>()) { 4816 QualType rpointee = RHSPTy->getPointeeType(); 4817 4818 // RHS must be a completely-type object type. 4819 // Handle the GNU void* extension. 4820 if (rpointee->isVoidType()) { 4821 if (getLangOptions().CPlusPlus) { 4822 Diag(Loc, diag::err_typecheck_pointer_arith_void_type) 4823 << lex->getSourceRange() << rex->getSourceRange(); 4824 return QualType(); 4825 } 4826 4827 ComplainAboutVoid = true; 4828 } else if (rpointee->isFunctionType()) { 4829 if (getLangOptions().CPlusPlus) { 4830 Diag(Loc, diag::err_typecheck_pointer_arith_function_type) 4831 << rex->getType() << rex->getSourceRange(); 4832 return QualType(); 4833 } 4834 4835 // GNU extension: arithmetic on pointer to function 4836 if (!ComplainAboutFunc) 4837 ComplainAboutFunc = rex; 4838 } else if (!rpointee->isDependentType() && 4839 RequireCompleteType(Loc, rpointee, 4840 PDiag(diag::err_typecheck_sub_ptr_object) 4841 << rex->getSourceRange() 4842 << rex->getType())) 4843 return QualType(); 4844 4845 if (getLangOptions().CPlusPlus) { 4846 // Pointee types must be the same: C++ [expr.add] 4847 if (!Context.hasSameUnqualifiedType(lpointee, rpointee)) { 4848 Diag(Loc, diag::err_typecheck_sub_ptr_compatible) 4849 << lex->getType() << rex->getType() 4850 << lex->getSourceRange() << rex->getSourceRange(); 4851 return QualType(); 4852 } 4853 } else { 4854 // Pointee types must be compatible C99 6.5.6p3 4855 if (!Context.typesAreCompatible( 4856 Context.getCanonicalType(lpointee).getUnqualifiedType(), 4857 Context.getCanonicalType(rpointee).getUnqualifiedType())) { 4858 Diag(Loc, diag::err_typecheck_sub_ptr_compatible) 4859 << lex->getType() << rex->getType() 4860 << lex->getSourceRange() << rex->getSourceRange(); 4861 return QualType(); 4862 } 4863 } 4864 4865 if (ComplainAboutVoid) 4866 Diag(Loc, diag::ext_gnu_void_ptr) 4867 << lex->getSourceRange() << rex->getSourceRange(); 4868 if (ComplainAboutFunc) 4869 Diag(Loc, diag::ext_gnu_ptr_func_arith) 4870 << ComplainAboutFunc->getType() 4871 << ComplainAboutFunc->getSourceRange(); 4872 4873 if (CompLHSTy) *CompLHSTy = lex->getType(); 4874 return Context.getPointerDiffType(); 4875 } 4876 } 4877 4878 return InvalidOperands(Loc, lex, rex); 4879} 4880 4881// C99 6.5.7 4882QualType Sema::CheckShiftOperands(Expr *&lex, Expr *&rex, SourceLocation Loc, 4883 bool isCompAssign) { 4884 // C99 6.5.7p2: Each of the operands shall have integer type. 4885 if (!lex->getType()->isIntegerType() || !rex->getType()->isIntegerType()) 4886 return InvalidOperands(Loc, lex, rex); 4887 4888 // Vector shifts promote their scalar inputs to vector type. 4889 if (lex->getType()->isVectorType() || rex->getType()->isVectorType()) 4890 return CheckVectorOperands(Loc, lex, rex); 4891 4892 // Shifts don't perform usual arithmetic conversions, they just do integer 4893 // promotions on each operand. C99 6.5.7p3 4894 QualType LHSTy = Context.isPromotableBitField(lex); 4895 if (LHSTy.isNull()) { 4896 LHSTy = lex->getType(); 4897 if (LHSTy->isPromotableIntegerType()) 4898 LHSTy = Context.getPromotedIntegerType(LHSTy); 4899 } 4900 if (!isCompAssign) 4901 ImpCastExprToType(lex, LHSTy, CastExpr::CK_IntegralCast); 4902 4903 UsualUnaryConversions(rex); 4904 4905 // Sanity-check shift operands 4906 llvm::APSInt Right; 4907 // Check right/shifter operand 4908 if (!rex->isValueDependent() && 4909 rex->isIntegerConstantExpr(Right, Context)) { 4910 if (Right.isNegative()) 4911 Diag(Loc, diag::warn_shift_negative) << rex->getSourceRange(); 4912 else { 4913 llvm::APInt LeftBits(Right.getBitWidth(), 4914 Context.getTypeSize(lex->getType())); 4915 if (Right.uge(LeftBits)) 4916 Diag(Loc, diag::warn_shift_gt_typewidth) << rex->getSourceRange(); 4917 } 4918 } 4919 4920 // "The type of the result is that of the promoted left operand." 4921 return LHSTy; 4922} 4923 4924/// \brief Implements -Wsign-compare. 4925/// 4926/// \param lex the left-hand expression 4927/// \param rex the right-hand expression 4928/// \param OpLoc the location of the joining operator 4929/// \param Equality whether this is an "equality-like" join, which 4930/// suppresses the warning in some cases 4931void Sema::CheckSignCompare(Expr *lex, Expr *rex, SourceLocation OpLoc, 4932 const PartialDiagnostic &PD, bool Equality) { 4933 // Don't warn if we're in an unevaluated context. 4934 if (ExprEvalContexts.back().Context == Unevaluated) 4935 return; 4936 4937 QualType lt = lex->getType(), rt = rex->getType(); 4938 4939 // Only warn if both operands are integral. 4940 if (!lt->isIntegerType() || !rt->isIntegerType()) 4941 return; 4942 4943 // If either expression is value-dependent, don't warn. We'll get another 4944 // chance at instantiation time. 4945 if (lex->isValueDependent() || rex->isValueDependent()) 4946 return; 4947 4948 // The rule is that the signed operand becomes unsigned, so isolate the 4949 // signed operand. 4950 Expr *signedOperand, *unsignedOperand; 4951 if (lt->isSignedIntegerType()) { 4952 if (rt->isSignedIntegerType()) return; 4953 signedOperand = lex; 4954 unsignedOperand = rex; 4955 } else { 4956 if (!rt->isSignedIntegerType()) return; 4957 signedOperand = rex; 4958 unsignedOperand = lex; 4959 } 4960 4961 // If the unsigned type is strictly smaller than the signed type, 4962 // then (1) the result type will be signed and (2) the unsigned 4963 // value will fit fully within the signed type, and thus the result 4964 // of the comparison will be exact. 4965 if (Context.getIntWidth(signedOperand->getType()) > 4966 Context.getIntWidth(unsignedOperand->getType())) 4967 return; 4968 4969 // If the value is a non-negative integer constant, then the 4970 // signed->unsigned conversion won't change it. 4971 llvm::APSInt value; 4972 if (signedOperand->isIntegerConstantExpr(value, Context)) { 4973 assert(value.isSigned() && "result of signed expression not signed"); 4974 4975 if (value.isNonNegative()) 4976 return; 4977 } 4978 4979 if (Equality) { 4980 // For (in)equality comparisons, if the unsigned operand is a 4981 // constant which cannot collide with a overflowed signed operand, 4982 // then reinterpreting the signed operand as unsigned will not 4983 // change the result of the comparison. 4984 if (unsignedOperand->isIntegerConstantExpr(value, Context)) { 4985 assert(!value.isSigned() && "result of unsigned expression is signed"); 4986 4987 // 2's complement: test the top bit. 4988 if (value.isNonNegative()) 4989 return; 4990 } 4991 } 4992 4993 Diag(OpLoc, PD) 4994 << lex->getType() << rex->getType() 4995 << lex->getSourceRange() << rex->getSourceRange(); 4996} 4997 4998// C99 6.5.8, C++ [expr.rel] 4999QualType Sema::CheckCompareOperands(Expr *&lex, Expr *&rex, SourceLocation Loc, 5000 unsigned OpaqueOpc, bool isRelational) { 5001 BinaryOperator::Opcode Opc = (BinaryOperator::Opcode)OpaqueOpc; 5002 5003 if (lex->getType()->isVectorType() || rex->getType()->isVectorType()) 5004 return CheckVectorCompareOperands(lex, rex, Loc, isRelational); 5005 5006 CheckSignCompare(lex, rex, Loc, diag::warn_mixed_sign_comparison, 5007 (Opc == BinaryOperator::EQ || Opc == BinaryOperator::NE)); 5008 5009 // C99 6.5.8p3 / C99 6.5.9p4 5010 if (lex->getType()->isArithmeticType() && rex->getType()->isArithmeticType()) 5011 UsualArithmeticConversions(lex, rex); 5012 else { 5013 UsualUnaryConversions(lex); 5014 UsualUnaryConversions(rex); 5015 } 5016 QualType lType = lex->getType(); 5017 QualType rType = rex->getType(); 5018 5019 if (!lType->isFloatingType() 5020 && !(lType->isBlockPointerType() && isRelational)) { 5021 // For non-floating point types, check for self-comparisons of the form 5022 // x == x, x != x, x < x, etc. These always evaluate to a constant, and 5023 // often indicate logic errors in the program. 5024 // NOTE: Don't warn about comparisons of enum constants. These can arise 5025 // from macro expansions, and are usually quite deliberate. 5026 Expr *LHSStripped = lex->IgnoreParens(); 5027 Expr *RHSStripped = rex->IgnoreParens(); 5028 if (DeclRefExpr* DRL = dyn_cast<DeclRefExpr>(LHSStripped)) 5029 if (DeclRefExpr* DRR = dyn_cast<DeclRefExpr>(RHSStripped)) 5030 if (DRL->getDecl() == DRR->getDecl() && 5031 !isa<EnumConstantDecl>(DRL->getDecl())) 5032 Diag(Loc, diag::warn_selfcomparison); 5033 5034 if (isa<CastExpr>(LHSStripped)) 5035 LHSStripped = LHSStripped->IgnoreParenCasts(); 5036 if (isa<CastExpr>(RHSStripped)) 5037 RHSStripped = RHSStripped->IgnoreParenCasts(); 5038 5039 // Warn about comparisons against a string constant (unless the other 5040 // operand is null), the user probably wants strcmp. 5041 Expr *literalString = 0; 5042 Expr *literalStringStripped = 0; 5043 if ((isa<StringLiteral>(LHSStripped) || isa<ObjCEncodeExpr>(LHSStripped)) && 5044 !RHSStripped->isNullPointerConstant(Context, 5045 Expr::NPC_ValueDependentIsNull)) { 5046 literalString = lex; 5047 literalStringStripped = LHSStripped; 5048 } else if ((isa<StringLiteral>(RHSStripped) || 5049 isa<ObjCEncodeExpr>(RHSStripped)) && 5050 !LHSStripped->isNullPointerConstant(Context, 5051 Expr::NPC_ValueDependentIsNull)) { 5052 literalString = rex; 5053 literalStringStripped = RHSStripped; 5054 } 5055 5056 if (literalString) { 5057 std::string resultComparison; 5058 switch (Opc) { 5059 case BinaryOperator::LT: resultComparison = ") < 0"; break; 5060 case BinaryOperator::GT: resultComparison = ") > 0"; break; 5061 case BinaryOperator::LE: resultComparison = ") <= 0"; break; 5062 case BinaryOperator::GE: resultComparison = ") >= 0"; break; 5063 case BinaryOperator::EQ: resultComparison = ") == 0"; break; 5064 case BinaryOperator::NE: resultComparison = ") != 0"; break; 5065 default: assert(false && "Invalid comparison operator"); 5066 } 5067 Diag(Loc, diag::warn_stringcompare) 5068 << isa<ObjCEncodeExpr>(literalStringStripped) 5069 << literalString->getSourceRange() 5070 << CodeModificationHint::CreateReplacement(SourceRange(Loc), ", ") 5071 << CodeModificationHint::CreateInsertion(lex->getLocStart(), 5072 "strcmp(") 5073 << CodeModificationHint::CreateInsertion( 5074 PP.getLocForEndOfToken(rex->getLocEnd()), 5075 resultComparison); 5076 } 5077 } 5078 5079 // The result of comparisons is 'bool' in C++, 'int' in C. 5080 QualType ResultTy = getLangOptions().CPlusPlus? Context.BoolTy :Context.IntTy; 5081 5082 if (isRelational) { 5083 if (lType->isRealType() && rType->isRealType()) 5084 return ResultTy; 5085 } else { 5086 // Check for comparisons of floating point operands using != and ==. 5087 if (lType->isFloatingType()) { 5088 assert(rType->isFloatingType()); 5089 CheckFloatComparison(Loc,lex,rex); 5090 } 5091 5092 if (lType->isArithmeticType() && rType->isArithmeticType()) 5093 return ResultTy; 5094 } 5095 5096 bool LHSIsNull = lex->isNullPointerConstant(Context, 5097 Expr::NPC_ValueDependentIsNull); 5098 bool RHSIsNull = rex->isNullPointerConstant(Context, 5099 Expr::NPC_ValueDependentIsNull); 5100 5101 // All of the following pointer related warnings are GCC extensions, except 5102 // when handling null pointer constants. One day, we can consider making them 5103 // errors (when -pedantic-errors is enabled). 5104 if (lType->isPointerType() && rType->isPointerType()) { // C99 6.5.8p2 5105 QualType LCanPointeeTy = 5106 Context.getCanonicalType(lType->getAs<PointerType>()->getPointeeType()); 5107 QualType RCanPointeeTy = 5108 Context.getCanonicalType(rType->getAs<PointerType>()->getPointeeType()); 5109 5110 if (getLangOptions().CPlusPlus) { 5111 if (LCanPointeeTy == RCanPointeeTy) 5112 return ResultTy; 5113 5114 // C++ [expr.rel]p2: 5115 // [...] Pointer conversions (4.10) and qualification 5116 // conversions (4.4) are performed on pointer operands (or on 5117 // a pointer operand and a null pointer constant) to bring 5118 // them to their composite pointer type. [...] 5119 // 5120 // C++ [expr.eq]p1 uses the same notion for (in)equality 5121 // comparisons of pointers. 5122 QualType T = FindCompositePointerType(lex, rex); 5123 if (T.isNull()) { 5124 Diag(Loc, diag::err_typecheck_comparison_of_distinct_pointers) 5125 << lType << rType << lex->getSourceRange() << rex->getSourceRange(); 5126 return QualType(); 5127 } 5128 5129 ImpCastExprToType(lex, T, CastExpr::CK_BitCast); 5130 ImpCastExprToType(rex, T, CastExpr::CK_BitCast); 5131 return ResultTy; 5132 } 5133 // C99 6.5.9p2 and C99 6.5.8p2 5134 if (Context.typesAreCompatible(LCanPointeeTy.getUnqualifiedType(), 5135 RCanPointeeTy.getUnqualifiedType())) { 5136 // Valid unless a relational comparison of function pointers 5137 if (isRelational && LCanPointeeTy->isFunctionType()) { 5138 Diag(Loc, diag::ext_typecheck_ordered_comparison_of_function_pointers) 5139 << lType << rType << lex->getSourceRange() << rex->getSourceRange(); 5140 } 5141 } else if (!isRelational && 5142 (LCanPointeeTy->isVoidType() || RCanPointeeTy->isVoidType())) { 5143 // Valid unless comparison between non-null pointer and function pointer 5144 if ((LCanPointeeTy->isFunctionType() || RCanPointeeTy->isFunctionType()) 5145 && !LHSIsNull && !RHSIsNull) { 5146 Diag(Loc, diag::ext_typecheck_comparison_of_fptr_to_void) 5147 << lType << rType << lex->getSourceRange() << rex->getSourceRange(); 5148 } 5149 } else { 5150 // Invalid 5151 Diag(Loc, diag::ext_typecheck_comparison_of_distinct_pointers) 5152 << lType << rType << lex->getSourceRange() << rex->getSourceRange(); 5153 } 5154 if (LCanPointeeTy != RCanPointeeTy) 5155 ImpCastExprToType(rex, lType, CastExpr::CK_BitCast); 5156 return ResultTy; 5157 } 5158 5159 if (getLangOptions().CPlusPlus) { 5160 // Comparison of pointers with null pointer constants and equality 5161 // comparisons of member pointers to null pointer constants. 5162 if (RHSIsNull && 5163 (lType->isPointerType() || 5164 (!isRelational && lType->isMemberPointerType()))) { 5165 ImpCastExprToType(rex, lType, CastExpr::CK_NullToMemberPointer); 5166 return ResultTy; 5167 } 5168 if (LHSIsNull && 5169 (rType->isPointerType() || 5170 (!isRelational && rType->isMemberPointerType()))) { 5171 ImpCastExprToType(lex, rType, CastExpr::CK_NullToMemberPointer); 5172 return ResultTy; 5173 } 5174 5175 // Comparison of member pointers. 5176 if (!isRelational && 5177 lType->isMemberPointerType() && rType->isMemberPointerType()) { 5178 // C++ [expr.eq]p2: 5179 // In addition, pointers to members can be compared, or a pointer to 5180 // member and a null pointer constant. Pointer to member conversions 5181 // (4.11) and qualification conversions (4.4) are performed to bring 5182 // them to a common type. If one operand is a null pointer constant, 5183 // the common type is the type of the other operand. Otherwise, the 5184 // common type is a pointer to member type similar (4.4) to the type 5185 // of one of the operands, with a cv-qualification signature (4.4) 5186 // that is the union of the cv-qualification signatures of the operand 5187 // types. 5188 QualType T = FindCompositePointerType(lex, rex); 5189 if (T.isNull()) { 5190 Diag(Loc, diag::err_typecheck_comparison_of_distinct_pointers) 5191 << lType << rType << lex->getSourceRange() << rex->getSourceRange(); 5192 return QualType(); 5193 } 5194 5195 ImpCastExprToType(lex, T, CastExpr::CK_BitCast); 5196 ImpCastExprToType(rex, T, CastExpr::CK_BitCast); 5197 return ResultTy; 5198 } 5199 5200 // Comparison of nullptr_t with itself. 5201 if (lType->isNullPtrType() && rType->isNullPtrType()) 5202 return ResultTy; 5203 } 5204 5205 // Handle block pointer types. 5206 if (!isRelational && lType->isBlockPointerType() && rType->isBlockPointerType()) { 5207 QualType lpointee = lType->getAs<BlockPointerType>()->getPointeeType(); 5208 QualType rpointee = rType->getAs<BlockPointerType>()->getPointeeType(); 5209 5210 if (!LHSIsNull && !RHSIsNull && 5211 !Context.typesAreCompatible(lpointee, rpointee)) { 5212 Diag(Loc, diag::err_typecheck_comparison_of_distinct_blocks) 5213 << lType << rType << lex->getSourceRange() << rex->getSourceRange(); 5214 } 5215 ImpCastExprToType(rex, lType, CastExpr::CK_BitCast); 5216 return ResultTy; 5217 } 5218 // Allow block pointers to be compared with null pointer constants. 5219 if (!isRelational 5220 && ((lType->isBlockPointerType() && rType->isPointerType()) 5221 || (lType->isPointerType() && rType->isBlockPointerType()))) { 5222 if (!LHSIsNull && !RHSIsNull) { 5223 if (!((rType->isPointerType() && rType->getAs<PointerType>() 5224 ->getPointeeType()->isVoidType()) 5225 || (lType->isPointerType() && lType->getAs<PointerType>() 5226 ->getPointeeType()->isVoidType()))) 5227 Diag(Loc, diag::err_typecheck_comparison_of_distinct_blocks) 5228 << lType << rType << lex->getSourceRange() << rex->getSourceRange(); 5229 } 5230 ImpCastExprToType(rex, lType, CastExpr::CK_BitCast); 5231 return ResultTy; 5232 } 5233 5234 if ((lType->isObjCObjectPointerType() || rType->isObjCObjectPointerType())) { 5235 if (lType->isPointerType() || rType->isPointerType()) { 5236 const PointerType *LPT = lType->getAs<PointerType>(); 5237 const PointerType *RPT = rType->getAs<PointerType>(); 5238 bool LPtrToVoid = LPT ? 5239 Context.getCanonicalType(LPT->getPointeeType())->isVoidType() : false; 5240 bool RPtrToVoid = RPT ? 5241 Context.getCanonicalType(RPT->getPointeeType())->isVoidType() : false; 5242 5243 if (!LPtrToVoid && !RPtrToVoid && 5244 !Context.typesAreCompatible(lType, rType)) { 5245 Diag(Loc, diag::ext_typecheck_comparison_of_distinct_pointers) 5246 << lType << rType << lex->getSourceRange() << rex->getSourceRange(); 5247 } 5248 ImpCastExprToType(rex, lType, CastExpr::CK_BitCast); 5249 return ResultTy; 5250 } 5251 if (lType->isObjCObjectPointerType() && rType->isObjCObjectPointerType()) { 5252 if (!Context.areComparableObjCPointerTypes(lType, rType)) 5253 Diag(Loc, diag::ext_typecheck_comparison_of_distinct_pointers) 5254 << lType << rType << lex->getSourceRange() << rex->getSourceRange(); 5255 ImpCastExprToType(rex, lType, CastExpr::CK_BitCast); 5256 return ResultTy; 5257 } 5258 } 5259 if (lType->isAnyPointerType() && rType->isIntegerType()) { 5260 unsigned DiagID = 0; 5261 if (RHSIsNull) { 5262 if (isRelational) 5263 DiagID = diag::ext_typecheck_ordered_comparison_of_pointer_and_zero; 5264 } else if (isRelational) 5265 DiagID = diag::ext_typecheck_ordered_comparison_of_pointer_integer; 5266 else 5267 DiagID = diag::ext_typecheck_comparison_of_pointer_integer; 5268 5269 if (DiagID) { 5270 Diag(Loc, DiagID) 5271 << lType << rType << lex->getSourceRange() << rex->getSourceRange(); 5272 } 5273 ImpCastExprToType(rex, lType, CastExpr::CK_IntegralToPointer); 5274 return ResultTy; 5275 } 5276 if (lType->isIntegerType() && rType->isAnyPointerType()) { 5277 unsigned DiagID = 0; 5278 if (LHSIsNull) { 5279 if (isRelational) 5280 DiagID = diag::ext_typecheck_ordered_comparison_of_pointer_and_zero; 5281 } else if (isRelational) 5282 DiagID = diag::ext_typecheck_ordered_comparison_of_pointer_integer; 5283 else 5284 DiagID = diag::ext_typecheck_comparison_of_pointer_integer; 5285 5286 if (DiagID) { 5287 Diag(Loc, DiagID) 5288 << lType << rType << lex->getSourceRange() << rex->getSourceRange(); 5289 } 5290 ImpCastExprToType(lex, rType, CastExpr::CK_IntegralToPointer); 5291 return ResultTy; 5292 } 5293 // Handle block pointers. 5294 if (!isRelational && RHSIsNull 5295 && lType->isBlockPointerType() && rType->isIntegerType()) { 5296 ImpCastExprToType(rex, lType, CastExpr::CK_IntegralToPointer); 5297 return ResultTy; 5298 } 5299 if (!isRelational && LHSIsNull 5300 && lType->isIntegerType() && rType->isBlockPointerType()) { 5301 ImpCastExprToType(lex, rType, CastExpr::CK_IntegralToPointer); 5302 return ResultTy; 5303 } 5304 return InvalidOperands(Loc, lex, rex); 5305} 5306 5307/// CheckVectorCompareOperands - vector comparisons are a clang extension that 5308/// operates on extended vector types. Instead of producing an IntTy result, 5309/// like a scalar comparison, a vector comparison produces a vector of integer 5310/// types. 5311QualType Sema::CheckVectorCompareOperands(Expr *&lex, Expr *&rex, 5312 SourceLocation Loc, 5313 bool isRelational) { 5314 // Check to make sure we're operating on vectors of the same type and width, 5315 // Allowing one side to be a scalar of element type. 5316 QualType vType = CheckVectorOperands(Loc, lex, rex); 5317 if (vType.isNull()) 5318 return vType; 5319 5320 QualType lType = lex->getType(); 5321 QualType rType = rex->getType(); 5322 5323 // For non-floating point types, check for self-comparisons of the form 5324 // x == x, x != x, x < x, etc. These always evaluate to a constant, and 5325 // often indicate logic errors in the program. 5326 if (!lType->isFloatingType()) { 5327 if (DeclRefExpr* DRL = dyn_cast<DeclRefExpr>(lex->IgnoreParens())) 5328 if (DeclRefExpr* DRR = dyn_cast<DeclRefExpr>(rex->IgnoreParens())) 5329 if (DRL->getDecl() == DRR->getDecl()) 5330 Diag(Loc, diag::warn_selfcomparison); 5331 } 5332 5333 // Check for comparisons of floating point operands using != and ==. 5334 if (!isRelational && lType->isFloatingType()) { 5335 assert (rType->isFloatingType()); 5336 CheckFloatComparison(Loc,lex,rex); 5337 } 5338 5339 // Return the type for the comparison, which is the same as vector type for 5340 // integer vectors, or an integer type of identical size and number of 5341 // elements for floating point vectors. 5342 if (lType->isIntegerType()) 5343 return lType; 5344 5345 const VectorType *VTy = lType->getAs<VectorType>(); 5346 unsigned TypeSize = Context.getTypeSize(VTy->getElementType()); 5347 if (TypeSize == Context.getTypeSize(Context.IntTy)) 5348 return Context.getExtVectorType(Context.IntTy, VTy->getNumElements()); 5349 if (TypeSize == Context.getTypeSize(Context.LongTy)) 5350 return Context.getExtVectorType(Context.LongTy, VTy->getNumElements()); 5351 5352 assert(TypeSize == Context.getTypeSize(Context.LongLongTy) && 5353 "Unhandled vector element size in vector compare"); 5354 return Context.getExtVectorType(Context.LongLongTy, VTy->getNumElements()); 5355} 5356 5357inline QualType Sema::CheckBitwiseOperands( 5358 Expr *&lex, Expr *&rex, SourceLocation Loc, bool isCompAssign) { 5359 if (lex->getType()->isVectorType() || rex->getType()->isVectorType()) 5360 return CheckVectorOperands(Loc, lex, rex); 5361 5362 QualType compType = UsualArithmeticConversions(lex, rex, isCompAssign); 5363 5364 if (lex->getType()->isIntegerType() && rex->getType()->isIntegerType()) 5365 return compType; 5366 return InvalidOperands(Loc, lex, rex); 5367} 5368 5369inline QualType Sema::CheckLogicalOperands( // C99 6.5.[13,14] 5370 Expr *&lex, Expr *&rex, SourceLocation Loc) { 5371 if (!Context.getLangOptions().CPlusPlus) { 5372 UsualUnaryConversions(lex); 5373 UsualUnaryConversions(rex); 5374 5375 if (!lex->getType()->isScalarType() || !rex->getType()->isScalarType()) 5376 return InvalidOperands(Loc, lex, rex); 5377 5378 return Context.IntTy; 5379 } 5380 5381 // C++ [expr.log.and]p1 5382 // C++ [expr.log.or]p1 5383 // The operands are both implicitly converted to type bool (clause 4). 5384 StandardConversionSequence LHS; 5385 if (!IsStandardConversion(lex, Context.BoolTy, 5386 /*InOverloadResolution=*/false, LHS)) 5387 return InvalidOperands(Loc, lex, rex); 5388 5389 if (PerformImplicitConversion(lex, Context.BoolTy, LHS, 5390 "passing", /*IgnoreBaseAccess=*/false)) 5391 return InvalidOperands(Loc, lex, rex); 5392 5393 StandardConversionSequence RHS; 5394 if (!IsStandardConversion(rex, Context.BoolTy, 5395 /*InOverloadResolution=*/false, RHS)) 5396 return InvalidOperands(Loc, lex, rex); 5397 5398 if (PerformImplicitConversion(rex, Context.BoolTy, RHS, 5399 "passing", /*IgnoreBaseAccess=*/false)) 5400 return InvalidOperands(Loc, lex, rex); 5401 5402 // C++ [expr.log.and]p2 5403 // C++ [expr.log.or]p2 5404 // The result is a bool. 5405 return Context.BoolTy; 5406} 5407 5408/// IsReadonlyProperty - Verify that otherwise a valid l-value expression 5409/// is a read-only property; return true if so. A readonly property expression 5410/// depends on various declarations and thus must be treated specially. 5411/// 5412static bool IsReadonlyProperty(Expr *E, Sema &S) { 5413 if (E->getStmtClass() == Expr::ObjCPropertyRefExprClass) { 5414 const ObjCPropertyRefExpr* PropExpr = cast<ObjCPropertyRefExpr>(E); 5415 if (ObjCPropertyDecl *PDecl = PropExpr->getProperty()) { 5416 QualType BaseType = PropExpr->getBase()->getType(); 5417 if (const ObjCObjectPointerType *OPT = 5418 BaseType->getAsObjCInterfacePointerType()) 5419 if (ObjCInterfaceDecl *IFace = OPT->getInterfaceDecl()) 5420 if (S.isPropertyReadonly(PDecl, IFace)) 5421 return true; 5422 } 5423 } 5424 return false; 5425} 5426 5427/// CheckForModifiableLvalue - Verify that E is a modifiable lvalue. If not, 5428/// emit an error and return true. If so, return false. 5429static bool CheckForModifiableLvalue(Expr *E, SourceLocation Loc, Sema &S) { 5430 SourceLocation OrigLoc = Loc; 5431 Expr::isModifiableLvalueResult IsLV = E->isModifiableLvalue(S.Context, 5432 &Loc); 5433 if (IsLV == Expr::MLV_Valid && IsReadonlyProperty(E, S)) 5434 IsLV = Expr::MLV_ReadonlyProperty; 5435 if (IsLV == Expr::MLV_Valid) 5436 return false; 5437 5438 unsigned Diag = 0; 5439 bool NeedType = false; 5440 switch (IsLV) { // C99 6.5.16p2 5441 default: assert(0 && "Unknown result from isModifiableLvalue!"); 5442 case Expr::MLV_ConstQualified: Diag = diag::err_typecheck_assign_const; break; 5443 case Expr::MLV_ArrayType: 5444 Diag = diag::err_typecheck_array_not_modifiable_lvalue; 5445 NeedType = true; 5446 break; 5447 case Expr::MLV_NotObjectType: 5448 Diag = diag::err_typecheck_non_object_not_modifiable_lvalue; 5449 NeedType = true; 5450 break; 5451 case Expr::MLV_LValueCast: 5452 Diag = diag::err_typecheck_lvalue_casts_not_supported; 5453 break; 5454 case Expr::MLV_InvalidExpression: 5455 Diag = diag::err_typecheck_expression_not_modifiable_lvalue; 5456 break; 5457 case Expr::MLV_IncompleteType: 5458 case Expr::MLV_IncompleteVoidType: 5459 return S.RequireCompleteType(Loc, E->getType(), 5460 PDiag(diag::err_typecheck_incomplete_type_not_modifiable_lvalue) 5461 << E->getSourceRange()); 5462 case Expr::MLV_DuplicateVectorComponents: 5463 Diag = diag::err_typecheck_duplicate_vector_components_not_mlvalue; 5464 break; 5465 case Expr::MLV_NotBlockQualified: 5466 Diag = diag::err_block_decl_ref_not_modifiable_lvalue; 5467 break; 5468 case Expr::MLV_ReadonlyProperty: 5469 Diag = diag::error_readonly_property_assignment; 5470 break; 5471 case Expr::MLV_NoSetterProperty: 5472 Diag = diag::error_nosetter_property_assignment; 5473 break; 5474 } 5475 5476 SourceRange Assign; 5477 if (Loc != OrigLoc) 5478 Assign = SourceRange(OrigLoc, OrigLoc); 5479 if (NeedType) 5480 S.Diag(Loc, Diag) << E->getType() << E->getSourceRange() << Assign; 5481 else 5482 S.Diag(Loc, Diag) << E->getSourceRange() << Assign; 5483 return true; 5484} 5485 5486 5487 5488// C99 6.5.16.1 5489QualType Sema::CheckAssignmentOperands(Expr *LHS, Expr *&RHS, 5490 SourceLocation Loc, 5491 QualType CompoundType) { 5492 // Verify that LHS is a modifiable lvalue, and emit error if not. 5493 if (CheckForModifiableLvalue(LHS, Loc, *this)) 5494 return QualType(); 5495 5496 QualType LHSType = LHS->getType(); 5497 QualType RHSType = CompoundType.isNull() ? RHS->getType() : CompoundType; 5498 5499 AssignConvertType ConvTy; 5500 if (CompoundType.isNull()) { 5501 // Simple assignment "x = y". 5502 ConvTy = CheckSingleAssignmentConstraints(LHSType, RHS); 5503 // Special case of NSObject attributes on c-style pointer types. 5504 if (ConvTy == IncompatiblePointer && 5505 ((Context.isObjCNSObjectType(LHSType) && 5506 RHSType->isObjCObjectPointerType()) || 5507 (Context.isObjCNSObjectType(RHSType) && 5508 LHSType->isObjCObjectPointerType()))) 5509 ConvTy = Compatible; 5510 5511 // If the RHS is a unary plus or minus, check to see if they = and + are 5512 // right next to each other. If so, the user may have typo'd "x =+ 4" 5513 // instead of "x += 4". 5514 Expr *RHSCheck = RHS; 5515 if (ImplicitCastExpr *ICE = dyn_cast<ImplicitCastExpr>(RHSCheck)) 5516 RHSCheck = ICE->getSubExpr(); 5517 if (UnaryOperator *UO = dyn_cast<UnaryOperator>(RHSCheck)) { 5518 if ((UO->getOpcode() == UnaryOperator::Plus || 5519 UO->getOpcode() == UnaryOperator::Minus) && 5520 Loc.isFileID() && UO->getOperatorLoc().isFileID() && 5521 // Only if the two operators are exactly adjacent. 5522 Loc.getFileLocWithOffset(1) == UO->getOperatorLoc() && 5523 // And there is a space or other character before the subexpr of the 5524 // unary +/-. We don't want to warn on "x=-1". 5525 Loc.getFileLocWithOffset(2) != UO->getSubExpr()->getLocStart() && 5526 UO->getSubExpr()->getLocStart().isFileID()) { 5527 Diag(Loc, diag::warn_not_compound_assign) 5528 << (UO->getOpcode() == UnaryOperator::Plus ? "+" : "-") 5529 << SourceRange(UO->getOperatorLoc(), UO->getOperatorLoc()); 5530 } 5531 } 5532 } else { 5533 // Compound assignment "x += y" 5534 ConvTy = CheckAssignmentConstraints(LHSType, RHSType); 5535 } 5536 5537 if (DiagnoseAssignmentResult(ConvTy, Loc, LHSType, RHSType, 5538 RHS, "assigning")) 5539 return QualType(); 5540 5541 // C99 6.5.16p3: The type of an assignment expression is the type of the 5542 // left operand unless the left operand has qualified type, in which case 5543 // it is the unqualified version of the type of the left operand. 5544 // C99 6.5.16.1p2: In simple assignment, the value of the right operand 5545 // is converted to the type of the assignment expression (above). 5546 // C++ 5.17p1: the type of the assignment expression is that of its left 5547 // operand. 5548 return LHSType.getUnqualifiedType(); 5549} 5550 5551// C99 6.5.17 5552QualType Sema::CheckCommaOperands(Expr *LHS, Expr *&RHS, SourceLocation Loc) { 5553 // Comma performs lvalue conversion (C99 6.3.2.1), but not unary conversions. 5554 DefaultFunctionArrayConversion(RHS); 5555 5556 // FIXME: Check that RHS type is complete in C mode (it's legal for it to be 5557 // incomplete in C++). 5558 5559 return RHS->getType(); 5560} 5561 5562/// CheckIncrementDecrementOperand - unlike most "Check" methods, this routine 5563/// doesn't need to call UsualUnaryConversions or UsualArithmeticConversions. 5564QualType Sema::CheckIncrementDecrementOperand(Expr *Op, SourceLocation OpLoc, 5565 bool isInc) { 5566 if (Op->isTypeDependent()) 5567 return Context.DependentTy; 5568 5569 QualType ResType = Op->getType(); 5570 assert(!ResType.isNull() && "no type for increment/decrement expression"); 5571 5572 if (getLangOptions().CPlusPlus && ResType->isBooleanType()) { 5573 // Decrement of bool is not allowed. 5574 if (!isInc) { 5575 Diag(OpLoc, diag::err_decrement_bool) << Op->getSourceRange(); 5576 return QualType(); 5577 } 5578 // Increment of bool sets it to true, but is deprecated. 5579 Diag(OpLoc, diag::warn_increment_bool) << Op->getSourceRange(); 5580 } else if (ResType->isRealType()) { 5581 // OK! 5582 } else if (ResType->isAnyPointerType()) { 5583 QualType PointeeTy = ResType->getPointeeType(); 5584 5585 // C99 6.5.2.4p2, 6.5.6p2 5586 if (PointeeTy->isVoidType()) { 5587 if (getLangOptions().CPlusPlus) { 5588 Diag(OpLoc, diag::err_typecheck_pointer_arith_void_type) 5589 << Op->getSourceRange(); 5590 return QualType(); 5591 } 5592 5593 // Pointer to void is a GNU extension in C. 5594 Diag(OpLoc, diag::ext_gnu_void_ptr) << Op->getSourceRange(); 5595 } else if (PointeeTy->isFunctionType()) { 5596 if (getLangOptions().CPlusPlus) { 5597 Diag(OpLoc, diag::err_typecheck_pointer_arith_function_type) 5598 << Op->getType() << Op->getSourceRange(); 5599 return QualType(); 5600 } 5601 5602 Diag(OpLoc, diag::ext_gnu_ptr_func_arith) 5603 << ResType << Op->getSourceRange(); 5604 } else if (RequireCompleteType(OpLoc, PointeeTy, 5605 PDiag(diag::err_typecheck_arithmetic_incomplete_type) 5606 << Op->getSourceRange() 5607 << ResType)) 5608 return QualType(); 5609 // Diagnose bad cases where we step over interface counts. 5610 else if (PointeeTy->isObjCInterfaceType() && LangOpts.ObjCNonFragileABI) { 5611 Diag(OpLoc, diag::err_arithmetic_nonfragile_interface) 5612 << PointeeTy << Op->getSourceRange(); 5613 return QualType(); 5614 } 5615 } else if (ResType->isComplexType()) { 5616 // C99 does not support ++/-- on complex types, we allow as an extension. 5617 Diag(OpLoc, diag::ext_integer_increment_complex) 5618 << ResType << Op->getSourceRange(); 5619 } else { 5620 Diag(OpLoc, diag::err_typecheck_illegal_increment_decrement) 5621 << ResType << Op->getSourceRange(); 5622 return QualType(); 5623 } 5624 // At this point, we know we have a real, complex or pointer type. 5625 // Now make sure the operand is a modifiable lvalue. 5626 if (CheckForModifiableLvalue(Op, OpLoc, *this)) 5627 return QualType(); 5628 return ResType; 5629} 5630 5631/// getPrimaryDecl - Helper function for CheckAddressOfOperand(). 5632/// This routine allows us to typecheck complex/recursive expressions 5633/// where the declaration is needed for type checking. We only need to 5634/// handle cases when the expression references a function designator 5635/// or is an lvalue. Here are some examples: 5636/// - &(x) => x 5637/// - &*****f => f for f a function designator. 5638/// - &s.xx => s 5639/// - &s.zz[1].yy -> s, if zz is an array 5640/// - *(x + 1) -> x, if x is an array 5641/// - &"123"[2] -> 0 5642/// - & __real__ x -> x 5643static NamedDecl *getPrimaryDecl(Expr *E) { 5644 switch (E->getStmtClass()) { 5645 case Stmt::DeclRefExprClass: 5646 return cast<DeclRefExpr>(E)->getDecl(); 5647 case Stmt::MemberExprClass: 5648 // If this is an arrow operator, the address is an offset from 5649 // the base's value, so the object the base refers to is 5650 // irrelevant. 5651 if (cast<MemberExpr>(E)->isArrow()) 5652 return 0; 5653 // Otherwise, the expression refers to a part of the base 5654 return getPrimaryDecl(cast<MemberExpr>(E)->getBase()); 5655 case Stmt::ArraySubscriptExprClass: { 5656 // FIXME: This code shouldn't be necessary! We should catch the implicit 5657 // promotion of register arrays earlier. 5658 Expr* Base = cast<ArraySubscriptExpr>(E)->getBase(); 5659 if (ImplicitCastExpr* ICE = dyn_cast<ImplicitCastExpr>(Base)) { 5660 if (ICE->getSubExpr()->getType()->isArrayType()) 5661 return getPrimaryDecl(ICE->getSubExpr()); 5662 } 5663 return 0; 5664 } 5665 case Stmt::UnaryOperatorClass: { 5666 UnaryOperator *UO = cast<UnaryOperator>(E); 5667 5668 switch(UO->getOpcode()) { 5669 case UnaryOperator::Real: 5670 case UnaryOperator::Imag: 5671 case UnaryOperator::Extension: 5672 return getPrimaryDecl(UO->getSubExpr()); 5673 default: 5674 return 0; 5675 } 5676 } 5677 case Stmt::ParenExprClass: 5678 return getPrimaryDecl(cast<ParenExpr>(E)->getSubExpr()); 5679 case Stmt::ImplicitCastExprClass: 5680 // If the result of an implicit cast is an l-value, we care about 5681 // the sub-expression; otherwise, the result here doesn't matter. 5682 return getPrimaryDecl(cast<ImplicitCastExpr>(E)->getSubExpr()); 5683 default: 5684 return 0; 5685 } 5686} 5687 5688/// CheckAddressOfOperand - The operand of & must be either a function 5689/// designator or an lvalue designating an object. If it is an lvalue, the 5690/// object cannot be declared with storage class register or be a bit field. 5691/// Note: The usual conversions are *not* applied to the operand of the & 5692/// operator (C99 6.3.2.1p[2-4]), and its result is never an lvalue. 5693/// In C++, the operand might be an overloaded function name, in which case 5694/// we allow the '&' but retain the overloaded-function type. 5695QualType Sema::CheckAddressOfOperand(Expr *op, SourceLocation OpLoc) { 5696 // Make sure to ignore parentheses in subsequent checks 5697 op = op->IgnoreParens(); 5698 5699 if (op->isTypeDependent()) 5700 return Context.DependentTy; 5701 5702 if (getLangOptions().C99) { 5703 // Implement C99-only parts of addressof rules. 5704 if (UnaryOperator* uOp = dyn_cast<UnaryOperator>(op)) { 5705 if (uOp->getOpcode() == UnaryOperator::Deref) 5706 // Per C99 6.5.3.2, the address of a deref always returns a valid result 5707 // (assuming the deref expression is valid). 5708 return uOp->getSubExpr()->getType(); 5709 } 5710 // Technically, there should be a check for array subscript 5711 // expressions here, but the result of one is always an lvalue anyway. 5712 } 5713 NamedDecl *dcl = getPrimaryDecl(op); 5714 Expr::isLvalueResult lval = op->isLvalue(Context); 5715 5716 if (lval != Expr::LV_Valid && lval != Expr::LV_IncompleteVoidType) { 5717 // C99 6.5.3.2p1 5718 // The operand must be either an l-value or a function designator 5719 if (!op->getType()->isFunctionType()) { 5720 // FIXME: emit more specific diag... 5721 Diag(OpLoc, diag::err_typecheck_invalid_lvalue_addrof) 5722 << op->getSourceRange(); 5723 return QualType(); 5724 } 5725 } else if (op->getBitField()) { // C99 6.5.3.2p1 5726 // The operand cannot be a bit-field 5727 Diag(OpLoc, diag::err_typecheck_address_of) 5728 << "bit-field" << op->getSourceRange(); 5729 return QualType(); 5730 } else if (isa<ExtVectorElementExpr>(op) || (isa<ArraySubscriptExpr>(op) && 5731 cast<ArraySubscriptExpr>(op)->getBase()->getType()->isVectorType())){ 5732 // The operand cannot be an element of a vector 5733 Diag(OpLoc, diag::err_typecheck_address_of) 5734 << "vector element" << op->getSourceRange(); 5735 return QualType(); 5736 } else if (isa<ObjCPropertyRefExpr>(op)) { 5737 // cannot take address of a property expression. 5738 Diag(OpLoc, diag::err_typecheck_address_of) 5739 << "property expression" << op->getSourceRange(); 5740 return QualType(); 5741 } else if (ConditionalOperator *CO = dyn_cast<ConditionalOperator>(op)) { 5742 // FIXME: Can LHS ever be null here? 5743 if (!CheckAddressOfOperand(CO->getTrueExpr(), OpLoc).isNull()) 5744 return CheckAddressOfOperand(CO->getFalseExpr(), OpLoc); 5745 } else if (isa<UnresolvedLookupExpr>(op)) { 5746 return Context.OverloadTy; 5747 } else if (dcl) { // C99 6.5.3.2p1 5748 // We have an lvalue with a decl. Make sure the decl is not declared 5749 // with the register storage-class specifier. 5750 if (const VarDecl *vd = dyn_cast<VarDecl>(dcl)) { 5751 if (vd->getStorageClass() == VarDecl::Register) { 5752 Diag(OpLoc, diag::err_typecheck_address_of) 5753 << "register variable" << op->getSourceRange(); 5754 return QualType(); 5755 } 5756 } else if (isa<FunctionTemplateDecl>(dcl)) { 5757 return Context.OverloadTy; 5758 } else if (FieldDecl *FD = dyn_cast<FieldDecl>(dcl)) { 5759 // Okay: we can take the address of a field. 5760 // Could be a pointer to member, though, if there is an explicit 5761 // scope qualifier for the class. 5762 if (isa<DeclRefExpr>(op) && cast<DeclRefExpr>(op)->getQualifier()) { 5763 DeclContext *Ctx = dcl->getDeclContext(); 5764 if (Ctx && Ctx->isRecord()) { 5765 if (FD->getType()->isReferenceType()) { 5766 Diag(OpLoc, 5767 diag::err_cannot_form_pointer_to_member_of_reference_type) 5768 << FD->getDeclName() << FD->getType(); 5769 return QualType(); 5770 } 5771 5772 return Context.getMemberPointerType(op->getType(), 5773 Context.getTypeDeclType(cast<RecordDecl>(Ctx)).getTypePtr()); 5774 } 5775 } 5776 } else if (CXXMethodDecl *MD = dyn_cast<CXXMethodDecl>(dcl)) { 5777 // Okay: we can take the address of a function. 5778 // As above. 5779 if (isa<DeclRefExpr>(op) && cast<DeclRefExpr>(op)->getQualifier() && 5780 MD->isInstance()) 5781 return Context.getMemberPointerType(op->getType(), 5782 Context.getTypeDeclType(MD->getParent()).getTypePtr()); 5783 } else if (!isa<FunctionDecl>(dcl)) 5784 assert(0 && "Unknown/unexpected decl type"); 5785 } 5786 5787 if (lval == Expr::LV_IncompleteVoidType) { 5788 // Taking the address of a void variable is technically illegal, but we 5789 // allow it in cases which are otherwise valid. 5790 // Example: "extern void x; void* y = &x;". 5791 Diag(OpLoc, diag::ext_typecheck_addrof_void) << op->getSourceRange(); 5792 } 5793 5794 // If the operand has type "type", the result has type "pointer to type". 5795 return Context.getPointerType(op->getType()); 5796} 5797 5798QualType Sema::CheckIndirectionOperand(Expr *Op, SourceLocation OpLoc) { 5799 if (Op->isTypeDependent()) 5800 return Context.DependentTy; 5801 5802 UsualUnaryConversions(Op); 5803 QualType Ty = Op->getType(); 5804 5805 // Note that per both C89 and C99, this is always legal, even if ptype is an 5806 // incomplete type or void. It would be possible to warn about dereferencing 5807 // a void pointer, but it's completely well-defined, and such a warning is 5808 // unlikely to catch any mistakes. 5809 if (const PointerType *PT = Ty->getAs<PointerType>()) 5810 return PT->getPointeeType(); 5811 5812 if (const ObjCObjectPointerType *OPT = Ty->getAs<ObjCObjectPointerType>()) 5813 return OPT->getPointeeType(); 5814 5815 Diag(OpLoc, diag::err_typecheck_indirection_requires_pointer) 5816 << Ty << Op->getSourceRange(); 5817 return QualType(); 5818} 5819 5820static inline BinaryOperator::Opcode ConvertTokenKindToBinaryOpcode( 5821 tok::TokenKind Kind) { 5822 BinaryOperator::Opcode Opc; 5823 switch (Kind) { 5824 default: assert(0 && "Unknown binop!"); 5825 case tok::periodstar: Opc = BinaryOperator::PtrMemD; break; 5826 case tok::arrowstar: Opc = BinaryOperator::PtrMemI; break; 5827 case tok::star: Opc = BinaryOperator::Mul; break; 5828 case tok::slash: Opc = BinaryOperator::Div; break; 5829 case tok::percent: Opc = BinaryOperator::Rem; break; 5830 case tok::plus: Opc = BinaryOperator::Add; break; 5831 case tok::minus: Opc = BinaryOperator::Sub; break; 5832 case tok::lessless: Opc = BinaryOperator::Shl; break; 5833 case tok::greatergreater: Opc = BinaryOperator::Shr; break; 5834 case tok::lessequal: Opc = BinaryOperator::LE; break; 5835 case tok::less: Opc = BinaryOperator::LT; break; 5836 case tok::greaterequal: Opc = BinaryOperator::GE; break; 5837 case tok::greater: Opc = BinaryOperator::GT; break; 5838 case tok::exclaimequal: Opc = BinaryOperator::NE; break; 5839 case tok::equalequal: Opc = BinaryOperator::EQ; break; 5840 case tok::amp: Opc = BinaryOperator::And; break; 5841 case tok::caret: Opc = BinaryOperator::Xor; break; 5842 case tok::pipe: Opc = BinaryOperator::Or; break; 5843 case tok::ampamp: Opc = BinaryOperator::LAnd; break; 5844 case tok::pipepipe: Opc = BinaryOperator::LOr; break; 5845 case tok::equal: Opc = BinaryOperator::Assign; break; 5846 case tok::starequal: Opc = BinaryOperator::MulAssign; break; 5847 case tok::slashequal: Opc = BinaryOperator::DivAssign; break; 5848 case tok::percentequal: Opc = BinaryOperator::RemAssign; break; 5849 case tok::plusequal: Opc = BinaryOperator::AddAssign; break; 5850 case tok::minusequal: Opc = BinaryOperator::SubAssign; break; 5851 case tok::lesslessequal: Opc = BinaryOperator::ShlAssign; break; 5852 case tok::greatergreaterequal: Opc = BinaryOperator::ShrAssign; break; 5853 case tok::ampequal: Opc = BinaryOperator::AndAssign; break; 5854 case tok::caretequal: Opc = BinaryOperator::XorAssign; break; 5855 case tok::pipeequal: Opc = BinaryOperator::OrAssign; break; 5856 case tok::comma: Opc = BinaryOperator::Comma; break; 5857 } 5858 return Opc; 5859} 5860 5861static inline UnaryOperator::Opcode ConvertTokenKindToUnaryOpcode( 5862 tok::TokenKind Kind) { 5863 UnaryOperator::Opcode Opc; 5864 switch (Kind) { 5865 default: assert(0 && "Unknown unary op!"); 5866 case tok::plusplus: Opc = UnaryOperator::PreInc; break; 5867 case tok::minusminus: Opc = UnaryOperator::PreDec; break; 5868 case tok::amp: Opc = UnaryOperator::AddrOf; break; 5869 case tok::star: Opc = UnaryOperator::Deref; break; 5870 case tok::plus: Opc = UnaryOperator::Plus; break; 5871 case tok::minus: Opc = UnaryOperator::Minus; break; 5872 case tok::tilde: Opc = UnaryOperator::Not; break; 5873 case tok::exclaim: Opc = UnaryOperator::LNot; break; 5874 case tok::kw___real: Opc = UnaryOperator::Real; break; 5875 case tok::kw___imag: Opc = UnaryOperator::Imag; break; 5876 case tok::kw___extension__: Opc = UnaryOperator::Extension; break; 5877 } 5878 return Opc; 5879} 5880 5881/// CreateBuiltinBinOp - Creates a new built-in binary operation with 5882/// operator @p Opc at location @c TokLoc. This routine only supports 5883/// built-in operations; ActOnBinOp handles overloaded operators. 5884Action::OwningExprResult Sema::CreateBuiltinBinOp(SourceLocation OpLoc, 5885 unsigned Op, 5886 Expr *lhs, Expr *rhs) { 5887 QualType ResultTy; // Result type of the binary operator. 5888 BinaryOperator::Opcode Opc = (BinaryOperator::Opcode)Op; 5889 // The following two variables are used for compound assignment operators 5890 QualType CompLHSTy; // Type of LHS after promotions for computation 5891 QualType CompResultTy; // Type of computation result 5892 5893 switch (Opc) { 5894 case BinaryOperator::Assign: 5895 ResultTy = CheckAssignmentOperands(lhs, rhs, OpLoc, QualType()); 5896 break; 5897 case BinaryOperator::PtrMemD: 5898 case BinaryOperator::PtrMemI: 5899 ResultTy = CheckPointerToMemberOperands(lhs, rhs, OpLoc, 5900 Opc == BinaryOperator::PtrMemI); 5901 break; 5902 case BinaryOperator::Mul: 5903 case BinaryOperator::Div: 5904 ResultTy = CheckMultiplyDivideOperands(lhs, rhs, OpLoc); 5905 break; 5906 case BinaryOperator::Rem: 5907 ResultTy = CheckRemainderOperands(lhs, rhs, OpLoc); 5908 break; 5909 case BinaryOperator::Add: 5910 ResultTy = CheckAdditionOperands(lhs, rhs, OpLoc); 5911 break; 5912 case BinaryOperator::Sub: 5913 ResultTy = CheckSubtractionOperands(lhs, rhs, OpLoc); 5914 break; 5915 case BinaryOperator::Shl: 5916 case BinaryOperator::Shr: 5917 ResultTy = CheckShiftOperands(lhs, rhs, OpLoc); 5918 break; 5919 case BinaryOperator::LE: 5920 case BinaryOperator::LT: 5921 case BinaryOperator::GE: 5922 case BinaryOperator::GT: 5923 ResultTy = CheckCompareOperands(lhs, rhs, OpLoc, Opc, true); 5924 break; 5925 case BinaryOperator::EQ: 5926 case BinaryOperator::NE: 5927 ResultTy = CheckCompareOperands(lhs, rhs, OpLoc, Opc, false); 5928 break; 5929 case BinaryOperator::And: 5930 case BinaryOperator::Xor: 5931 case BinaryOperator::Or: 5932 ResultTy = CheckBitwiseOperands(lhs, rhs, OpLoc); 5933 break; 5934 case BinaryOperator::LAnd: 5935 case BinaryOperator::LOr: 5936 ResultTy = CheckLogicalOperands(lhs, rhs, OpLoc); 5937 break; 5938 case BinaryOperator::MulAssign: 5939 case BinaryOperator::DivAssign: 5940 CompResultTy = CheckMultiplyDivideOperands(lhs, rhs, OpLoc, true); 5941 CompLHSTy = CompResultTy; 5942 if (!CompResultTy.isNull()) 5943 ResultTy = CheckAssignmentOperands(lhs, rhs, OpLoc, CompResultTy); 5944 break; 5945 case BinaryOperator::RemAssign: 5946 CompResultTy = CheckRemainderOperands(lhs, rhs, OpLoc, true); 5947 CompLHSTy = CompResultTy; 5948 if (!CompResultTy.isNull()) 5949 ResultTy = CheckAssignmentOperands(lhs, rhs, OpLoc, CompResultTy); 5950 break; 5951 case BinaryOperator::AddAssign: 5952 CompResultTy = CheckAdditionOperands(lhs, rhs, OpLoc, &CompLHSTy); 5953 if (!CompResultTy.isNull()) 5954 ResultTy = CheckAssignmentOperands(lhs, rhs, OpLoc, CompResultTy); 5955 break; 5956 case BinaryOperator::SubAssign: 5957 CompResultTy = CheckSubtractionOperands(lhs, rhs, OpLoc, &CompLHSTy); 5958 if (!CompResultTy.isNull()) 5959 ResultTy = CheckAssignmentOperands(lhs, rhs, OpLoc, CompResultTy); 5960 break; 5961 case BinaryOperator::ShlAssign: 5962 case BinaryOperator::ShrAssign: 5963 CompResultTy = CheckShiftOperands(lhs, rhs, OpLoc, true); 5964 CompLHSTy = CompResultTy; 5965 if (!CompResultTy.isNull()) 5966 ResultTy = CheckAssignmentOperands(lhs, rhs, OpLoc, CompResultTy); 5967 break; 5968 case BinaryOperator::AndAssign: 5969 case BinaryOperator::XorAssign: 5970 case BinaryOperator::OrAssign: 5971 CompResultTy = CheckBitwiseOperands(lhs, rhs, OpLoc, true); 5972 CompLHSTy = CompResultTy; 5973 if (!CompResultTy.isNull()) 5974 ResultTy = CheckAssignmentOperands(lhs, rhs, OpLoc, CompResultTy); 5975 break; 5976 case BinaryOperator::Comma: 5977 ResultTy = CheckCommaOperands(lhs, rhs, OpLoc); 5978 break; 5979 } 5980 if (ResultTy.isNull()) 5981 return ExprError(); 5982 if (CompResultTy.isNull()) 5983 return Owned(new (Context) BinaryOperator(lhs, rhs, Opc, ResultTy, OpLoc)); 5984 else 5985 return Owned(new (Context) CompoundAssignOperator(lhs, rhs, Opc, ResultTy, 5986 CompLHSTy, CompResultTy, 5987 OpLoc)); 5988} 5989 5990/// SuggestParentheses - Emit a diagnostic together with a fixit hint that wraps 5991/// ParenRange in parentheses. 5992static void SuggestParentheses(Sema &Self, SourceLocation Loc, 5993 const PartialDiagnostic &PD, 5994 SourceRange ParenRange) 5995{ 5996 SourceLocation EndLoc = Self.PP.getLocForEndOfToken(ParenRange.getEnd()); 5997 if (!ParenRange.getEnd().isFileID() || EndLoc.isInvalid()) { 5998 // We can't display the parentheses, so just dig the 5999 // warning/error and return. 6000 Self.Diag(Loc, PD); 6001 return; 6002 } 6003 6004 Self.Diag(Loc, PD) 6005 << CodeModificationHint::CreateInsertion(ParenRange.getBegin(), "(") 6006 << CodeModificationHint::CreateInsertion(EndLoc, ")"); 6007} 6008 6009/// DiagnoseBitwisePrecedence - Emit a warning when bitwise and comparison 6010/// operators are mixed in a way that suggests that the programmer forgot that 6011/// comparison operators have higher precedence. The most typical example of 6012/// such code is "flags & 0x0020 != 0", which is equivalent to "flags & 1". 6013static void DiagnoseBitwisePrecedence(Sema &Self, BinaryOperator::Opcode Opc, 6014 SourceLocation OpLoc,Expr *lhs,Expr *rhs){ 6015 typedef BinaryOperator BinOp; 6016 BinOp::Opcode lhsopc = static_cast<BinOp::Opcode>(-1), 6017 rhsopc = static_cast<BinOp::Opcode>(-1); 6018 if (BinOp *BO = dyn_cast<BinOp>(lhs)) 6019 lhsopc = BO->getOpcode(); 6020 if (BinOp *BO = dyn_cast<BinOp>(rhs)) 6021 rhsopc = BO->getOpcode(); 6022 6023 // Subs are not binary operators. 6024 if (lhsopc == -1 && rhsopc == -1) 6025 return; 6026 6027 // Bitwise operations are sometimes used as eager logical ops. 6028 // Don't diagnose this. 6029 if ((BinOp::isComparisonOp(lhsopc) || BinOp::isBitwiseOp(lhsopc)) && 6030 (BinOp::isComparisonOp(rhsopc) || BinOp::isBitwiseOp(rhsopc))) 6031 return; 6032 6033 if (BinOp::isComparisonOp(lhsopc)) 6034 SuggestParentheses(Self, OpLoc, 6035 PDiag(diag::warn_precedence_bitwise_rel) 6036 << SourceRange(lhs->getLocStart(), OpLoc) 6037 << BinOp::getOpcodeStr(Opc) << BinOp::getOpcodeStr(lhsopc), 6038 SourceRange(cast<BinOp>(lhs)->getRHS()->getLocStart(), rhs->getLocEnd())); 6039 else if (BinOp::isComparisonOp(rhsopc)) 6040 SuggestParentheses(Self, OpLoc, 6041 PDiag(diag::warn_precedence_bitwise_rel) 6042 << SourceRange(OpLoc, rhs->getLocEnd()) 6043 << BinOp::getOpcodeStr(Opc) << BinOp::getOpcodeStr(rhsopc), 6044 SourceRange(lhs->getLocEnd(), cast<BinOp>(rhs)->getLHS()->getLocStart())); 6045} 6046 6047/// DiagnoseBinOpPrecedence - Emit warnings for expressions with tricky 6048/// precedence. This currently diagnoses only "arg1 'bitwise' arg2 'eq' arg3". 6049/// But it could also warn about arg1 && arg2 || arg3, as GCC 4.3+ does. 6050static void DiagnoseBinOpPrecedence(Sema &Self, BinaryOperator::Opcode Opc, 6051 SourceLocation OpLoc, Expr *lhs, Expr *rhs){ 6052 if (BinaryOperator::isBitwiseOp(Opc)) 6053 DiagnoseBitwisePrecedence(Self, Opc, OpLoc, lhs, rhs); 6054} 6055 6056// Binary Operators. 'Tok' is the token for the operator. 6057Action::OwningExprResult Sema::ActOnBinOp(Scope *S, SourceLocation TokLoc, 6058 tok::TokenKind Kind, 6059 ExprArg LHS, ExprArg RHS) { 6060 BinaryOperator::Opcode Opc = ConvertTokenKindToBinaryOpcode(Kind); 6061 Expr *lhs = LHS.takeAs<Expr>(), *rhs = RHS.takeAs<Expr>(); 6062 6063 assert((lhs != 0) && "ActOnBinOp(): missing left expression"); 6064 assert((rhs != 0) && "ActOnBinOp(): missing right expression"); 6065 6066 // Emit warnings for tricky precedence issues, e.g. "bitfield & 0x4 == 0" 6067 DiagnoseBinOpPrecedence(*this, Opc, TokLoc, lhs, rhs); 6068 6069 return BuildBinOp(S, TokLoc, Opc, lhs, rhs); 6070} 6071 6072Action::OwningExprResult Sema::BuildBinOp(Scope *S, SourceLocation OpLoc, 6073 BinaryOperator::Opcode Opc, 6074 Expr *lhs, Expr *rhs) { 6075 if (getLangOptions().CPlusPlus && 6076 (lhs->getType()->isOverloadableType() || 6077 rhs->getType()->isOverloadableType())) { 6078 // Find all of the overloaded operators visible from this 6079 // point. We perform both an operator-name lookup from the local 6080 // scope and an argument-dependent lookup based on the types of 6081 // the arguments. 6082 FunctionSet Functions; 6083 OverloadedOperatorKind OverOp = BinaryOperator::getOverloadedOperator(Opc); 6084 if (OverOp != OO_None) { 6085 if (S) 6086 LookupOverloadedOperatorName(OverOp, S, lhs->getType(), rhs->getType(), 6087 Functions); 6088 Expr *Args[2] = { lhs, rhs }; 6089 DeclarationName OpName 6090 = Context.DeclarationNames.getCXXOperatorName(OverOp); 6091 ArgumentDependentLookup(OpName, /*Operator*/true, Args, 2, Functions); 6092 } 6093 6094 // Build the (potentially-overloaded, potentially-dependent) 6095 // binary operation. 6096 return CreateOverloadedBinOp(OpLoc, Opc, Functions, lhs, rhs); 6097 } 6098 6099 // Build a built-in binary operation. 6100 return CreateBuiltinBinOp(OpLoc, Opc, lhs, rhs); 6101} 6102 6103Action::OwningExprResult Sema::CreateBuiltinUnaryOp(SourceLocation OpLoc, 6104 unsigned OpcIn, 6105 ExprArg InputArg) { 6106 UnaryOperator::Opcode Opc = static_cast<UnaryOperator::Opcode>(OpcIn); 6107 6108 // FIXME: Input is modified below, but InputArg is not updated appropriately. 6109 Expr *Input = (Expr *)InputArg.get(); 6110 QualType resultType; 6111 switch (Opc) { 6112 case UnaryOperator::OffsetOf: 6113 assert(false && "Invalid unary operator"); 6114 break; 6115 6116 case UnaryOperator::PreInc: 6117 case UnaryOperator::PreDec: 6118 case UnaryOperator::PostInc: 6119 case UnaryOperator::PostDec: 6120 resultType = CheckIncrementDecrementOperand(Input, OpLoc, 6121 Opc == UnaryOperator::PreInc || 6122 Opc == UnaryOperator::PostInc); 6123 break; 6124 case UnaryOperator::AddrOf: 6125 resultType = CheckAddressOfOperand(Input, OpLoc); 6126 break; 6127 case UnaryOperator::Deref: 6128 DefaultFunctionArrayConversion(Input); 6129 resultType = CheckIndirectionOperand(Input, OpLoc); 6130 break; 6131 case UnaryOperator::Plus: 6132 case UnaryOperator::Minus: 6133 UsualUnaryConversions(Input); 6134 resultType = Input->getType(); 6135 if (resultType->isDependentType()) 6136 break; 6137 if (resultType->isArithmeticType()) // C99 6.5.3.3p1 6138 break; 6139 else if (getLangOptions().CPlusPlus && // C++ [expr.unary.op]p6-7 6140 resultType->isEnumeralType()) 6141 break; 6142 else if (getLangOptions().CPlusPlus && // C++ [expr.unary.op]p6 6143 Opc == UnaryOperator::Plus && 6144 resultType->isPointerType()) 6145 break; 6146 6147 return ExprError(Diag(OpLoc, diag::err_typecheck_unary_expr) 6148 << resultType << Input->getSourceRange()); 6149 case UnaryOperator::Not: // bitwise complement 6150 UsualUnaryConversions(Input); 6151 resultType = Input->getType(); 6152 if (resultType->isDependentType()) 6153 break; 6154 // C99 6.5.3.3p1. We allow complex int and float as a GCC extension. 6155 if (resultType->isComplexType() || resultType->isComplexIntegerType()) 6156 // C99 does not support '~' for complex conjugation. 6157 Diag(OpLoc, diag::ext_integer_complement_complex) 6158 << resultType << Input->getSourceRange(); 6159 else if (!resultType->isIntegerType()) 6160 return ExprError(Diag(OpLoc, diag::err_typecheck_unary_expr) 6161 << resultType << Input->getSourceRange()); 6162 break; 6163 case UnaryOperator::LNot: // logical negation 6164 // Unlike +/-/~, integer promotions aren't done here (C99 6.5.3.3p5). 6165 DefaultFunctionArrayConversion(Input); 6166 resultType = Input->getType(); 6167 if (resultType->isDependentType()) 6168 break; 6169 if (!resultType->isScalarType()) // C99 6.5.3.3p1 6170 return ExprError(Diag(OpLoc, diag::err_typecheck_unary_expr) 6171 << resultType << Input->getSourceRange()); 6172 // LNot always has type int. C99 6.5.3.3p5. 6173 // In C++, it's bool. C++ 5.3.1p8 6174 resultType = getLangOptions().CPlusPlus ? Context.BoolTy : Context.IntTy; 6175 break; 6176 case UnaryOperator::Real: 6177 case UnaryOperator::Imag: 6178 resultType = CheckRealImagOperand(Input, OpLoc, Opc == UnaryOperator::Real); 6179 break; 6180 case UnaryOperator::Extension: 6181 resultType = Input->getType(); 6182 break; 6183 } 6184 if (resultType.isNull()) 6185 return ExprError(); 6186 6187 InputArg.release(); 6188 return Owned(new (Context) UnaryOperator(Input, Opc, resultType, OpLoc)); 6189} 6190 6191Action::OwningExprResult Sema::BuildUnaryOp(Scope *S, SourceLocation OpLoc, 6192 UnaryOperator::Opcode Opc, 6193 ExprArg input) { 6194 Expr *Input = (Expr*)input.get(); 6195 if (getLangOptions().CPlusPlus && Input->getType()->isOverloadableType() && 6196 Opc != UnaryOperator::Extension) { 6197 // Find all of the overloaded operators visible from this 6198 // point. We perform both an operator-name lookup from the local 6199 // scope and an argument-dependent lookup based on the types of 6200 // the arguments. 6201 FunctionSet Functions; 6202 OverloadedOperatorKind OverOp = UnaryOperator::getOverloadedOperator(Opc); 6203 if (OverOp != OO_None) { 6204 if (S) 6205 LookupOverloadedOperatorName(OverOp, S, Input->getType(), QualType(), 6206 Functions); 6207 DeclarationName OpName 6208 = Context.DeclarationNames.getCXXOperatorName(OverOp); 6209 ArgumentDependentLookup(OpName, /*Operator*/true, &Input, 1, Functions); 6210 } 6211 6212 return CreateOverloadedUnaryOp(OpLoc, Opc, Functions, move(input)); 6213 } 6214 6215 return CreateBuiltinUnaryOp(OpLoc, Opc, move(input)); 6216} 6217 6218// Unary Operators. 'Tok' is the token for the operator. 6219Action::OwningExprResult Sema::ActOnUnaryOp(Scope *S, SourceLocation OpLoc, 6220 tok::TokenKind Op, ExprArg input) { 6221 return BuildUnaryOp(S, OpLoc, ConvertTokenKindToUnaryOpcode(Op), move(input)); 6222} 6223 6224/// ActOnAddrLabel - Parse the GNU address of label extension: "&&foo". 6225Sema::OwningExprResult Sema::ActOnAddrLabel(SourceLocation OpLoc, 6226 SourceLocation LabLoc, 6227 IdentifierInfo *LabelII) { 6228 // Look up the record for this label identifier. 6229 LabelStmt *&LabelDecl = getLabelMap()[LabelII]; 6230 6231 // If we haven't seen this label yet, create a forward reference. It 6232 // will be validated and/or cleaned up in ActOnFinishFunctionBody. 6233 if (LabelDecl == 0) 6234 LabelDecl = new (Context) LabelStmt(LabLoc, LabelII, 0); 6235 6236 // Create the AST node. The address of a label always has type 'void*'. 6237 return Owned(new (Context) AddrLabelExpr(OpLoc, LabLoc, LabelDecl, 6238 Context.getPointerType(Context.VoidTy))); 6239} 6240 6241Sema::OwningExprResult 6242Sema::ActOnStmtExpr(SourceLocation LPLoc, StmtArg substmt, 6243 SourceLocation RPLoc) { // "({..})" 6244 Stmt *SubStmt = static_cast<Stmt*>(substmt.get()); 6245 assert(SubStmt && isa<CompoundStmt>(SubStmt) && "Invalid action invocation!"); 6246 CompoundStmt *Compound = cast<CompoundStmt>(SubStmt); 6247 6248 bool isFileScope = getCurFunctionOrMethodDecl() == 0; 6249 if (isFileScope) 6250 return ExprError(Diag(LPLoc, diag::err_stmtexpr_file_scope)); 6251 6252 // FIXME: there are a variety of strange constraints to enforce here, for 6253 // example, it is not possible to goto into a stmt expression apparently. 6254 // More semantic analysis is needed. 6255 6256 // If there are sub stmts in the compound stmt, take the type of the last one 6257 // as the type of the stmtexpr. 6258 QualType Ty = Context.VoidTy; 6259 6260 if (!Compound->body_empty()) { 6261 Stmt *LastStmt = Compound->body_back(); 6262 // If LastStmt is a label, skip down through into the body. 6263 while (LabelStmt *Label = dyn_cast<LabelStmt>(LastStmt)) 6264 LastStmt = Label->getSubStmt(); 6265 6266 if (Expr *LastExpr = dyn_cast<Expr>(LastStmt)) 6267 Ty = LastExpr->getType(); 6268 } 6269 6270 // FIXME: Check that expression type is complete/non-abstract; statement 6271 // expressions are not lvalues. 6272 6273 substmt.release(); 6274 return Owned(new (Context) StmtExpr(Compound, Ty, LPLoc, RPLoc)); 6275} 6276 6277Sema::OwningExprResult Sema::ActOnBuiltinOffsetOf(Scope *S, 6278 SourceLocation BuiltinLoc, 6279 SourceLocation TypeLoc, 6280 TypeTy *argty, 6281 OffsetOfComponent *CompPtr, 6282 unsigned NumComponents, 6283 SourceLocation RPLoc) { 6284 // FIXME: This function leaks all expressions in the offset components on 6285 // error. 6286 // FIXME: Preserve type source info. 6287 QualType ArgTy = GetTypeFromParser(argty); 6288 assert(!ArgTy.isNull() && "Missing type argument!"); 6289 6290 bool Dependent = ArgTy->isDependentType(); 6291 6292 // We must have at least one component that refers to the type, and the first 6293 // one is known to be a field designator. Verify that the ArgTy represents 6294 // a struct/union/class. 6295 if (!Dependent && !ArgTy->isRecordType()) 6296 return ExprError(Diag(TypeLoc, diag::err_offsetof_record_type) << ArgTy); 6297 6298 // FIXME: Type must be complete per C99 7.17p3 because a declaring a variable 6299 // with an incomplete type would be illegal. 6300 6301 // Otherwise, create a null pointer as the base, and iteratively process 6302 // the offsetof designators. 6303 QualType ArgTyPtr = Context.getPointerType(ArgTy); 6304 Expr* Res = new (Context) ImplicitValueInitExpr(ArgTyPtr); 6305 Res = new (Context) UnaryOperator(Res, UnaryOperator::Deref, 6306 ArgTy, SourceLocation()); 6307 6308 // offsetof with non-identifier designators (e.g. "offsetof(x, a.b[c])") are a 6309 // GCC extension, diagnose them. 6310 // FIXME: This diagnostic isn't actually visible because the location is in 6311 // a system header! 6312 if (NumComponents != 1) 6313 Diag(BuiltinLoc, diag::ext_offsetof_extended_field_designator) 6314 << SourceRange(CompPtr[1].LocStart, CompPtr[NumComponents-1].LocEnd); 6315 6316 if (!Dependent) { 6317 bool DidWarnAboutNonPOD = false; 6318 6319 if (RequireCompleteType(TypeLoc, Res->getType(), 6320 diag::err_offsetof_incomplete_type)) 6321 return ExprError(); 6322 6323 // FIXME: Dependent case loses a lot of information here. And probably 6324 // leaks like a sieve. 6325 for (unsigned i = 0; i != NumComponents; ++i) { 6326 const OffsetOfComponent &OC = CompPtr[i]; 6327 if (OC.isBrackets) { 6328 // Offset of an array sub-field. TODO: Should we allow vector elements? 6329 const ArrayType *AT = Context.getAsArrayType(Res->getType()); 6330 if (!AT) { 6331 Res->Destroy(Context); 6332 return ExprError(Diag(OC.LocEnd, diag::err_offsetof_array_type) 6333 << Res->getType()); 6334 } 6335 6336 // FIXME: C++: Verify that operator[] isn't overloaded. 6337 6338 // Promote the array so it looks more like a normal array subscript 6339 // expression. 6340 DefaultFunctionArrayConversion(Res); 6341 6342 // C99 6.5.2.1p1 6343 Expr *Idx = static_cast<Expr*>(OC.U.E); 6344 // FIXME: Leaks Res 6345 if (!Idx->isTypeDependent() && !Idx->getType()->isIntegerType()) 6346 return ExprError(Diag(Idx->getLocStart(), 6347 diag::err_typecheck_subscript_not_integer) 6348 << Idx->getSourceRange()); 6349 6350 Res = new (Context) ArraySubscriptExpr(Res, Idx, AT->getElementType(), 6351 OC.LocEnd); 6352 continue; 6353 } 6354 6355 const RecordType *RC = Res->getType()->getAs<RecordType>(); 6356 if (!RC) { 6357 Res->Destroy(Context); 6358 return ExprError(Diag(OC.LocEnd, diag::err_offsetof_record_type) 6359 << Res->getType()); 6360 } 6361 6362 // Get the decl corresponding to this. 6363 RecordDecl *RD = RC->getDecl(); 6364 if (CXXRecordDecl *CRD = dyn_cast<CXXRecordDecl>(RD)) { 6365 if (!CRD->isPOD() && !DidWarnAboutNonPOD) { 6366 ExprError(Diag(BuiltinLoc, diag::warn_offsetof_non_pod_type) 6367 << SourceRange(CompPtr[0].LocStart, OC.LocEnd) 6368 << Res->getType()); 6369 DidWarnAboutNonPOD = true; 6370 } 6371 } 6372 6373 LookupResult R(*this, OC.U.IdentInfo, OC.LocStart, LookupMemberName); 6374 LookupQualifiedName(R, RD); 6375 6376 FieldDecl *MemberDecl = R.getAsSingle<FieldDecl>(); 6377 // FIXME: Leaks Res 6378 if (!MemberDecl) 6379 return ExprError(Diag(BuiltinLoc, diag::err_no_member) 6380 << OC.U.IdentInfo << RD << SourceRange(OC.LocStart, OC.LocEnd)); 6381 6382 // FIXME: C++: Verify that MemberDecl isn't a static field. 6383 // FIXME: Verify that MemberDecl isn't a bitfield. 6384 if (cast<RecordDecl>(MemberDecl->getDeclContext())->isAnonymousStructOrUnion()) { 6385 Res = BuildAnonymousStructUnionMemberReference( 6386 OC.LocEnd, MemberDecl, Res, OC.LocEnd).takeAs<Expr>(); 6387 } else { 6388 // MemberDecl->getType() doesn't get the right qualifiers, but it 6389 // doesn't matter here. 6390 Res = new (Context) MemberExpr(Res, false, MemberDecl, OC.LocEnd, 6391 MemberDecl->getType().getNonReferenceType()); 6392 } 6393 } 6394 } 6395 6396 return Owned(new (Context) UnaryOperator(Res, UnaryOperator::OffsetOf, 6397 Context.getSizeType(), BuiltinLoc)); 6398} 6399 6400 6401Sema::OwningExprResult Sema::ActOnTypesCompatibleExpr(SourceLocation BuiltinLoc, 6402 TypeTy *arg1,TypeTy *arg2, 6403 SourceLocation RPLoc) { 6404 // FIXME: Preserve type source info. 6405 QualType argT1 = GetTypeFromParser(arg1); 6406 QualType argT2 = GetTypeFromParser(arg2); 6407 6408 assert((!argT1.isNull() && !argT2.isNull()) && "Missing type argument(s)"); 6409 6410 if (getLangOptions().CPlusPlus) { 6411 Diag(BuiltinLoc, diag::err_types_compatible_p_in_cplusplus) 6412 << SourceRange(BuiltinLoc, RPLoc); 6413 return ExprError(); 6414 } 6415 6416 return Owned(new (Context) TypesCompatibleExpr(Context.IntTy, BuiltinLoc, 6417 argT1, argT2, RPLoc)); 6418} 6419 6420Sema::OwningExprResult Sema::ActOnChooseExpr(SourceLocation BuiltinLoc, 6421 ExprArg cond, 6422 ExprArg expr1, ExprArg expr2, 6423 SourceLocation RPLoc) { 6424 Expr *CondExpr = static_cast<Expr*>(cond.get()); 6425 Expr *LHSExpr = static_cast<Expr*>(expr1.get()); 6426 Expr *RHSExpr = static_cast<Expr*>(expr2.get()); 6427 6428 assert((CondExpr && LHSExpr && RHSExpr) && "Missing type argument(s)"); 6429 6430 QualType resType; 6431 bool ValueDependent = false; 6432 if (CondExpr->isTypeDependent() || CondExpr->isValueDependent()) { 6433 resType = Context.DependentTy; 6434 ValueDependent = true; 6435 } else { 6436 // The conditional expression is required to be a constant expression. 6437 llvm::APSInt condEval(32); 6438 SourceLocation ExpLoc; 6439 if (!CondExpr->isIntegerConstantExpr(condEval, Context, &ExpLoc)) 6440 return ExprError(Diag(ExpLoc, 6441 diag::err_typecheck_choose_expr_requires_constant) 6442 << CondExpr->getSourceRange()); 6443 6444 // If the condition is > zero, then the AST type is the same as the LSHExpr. 6445 resType = condEval.getZExtValue() ? LHSExpr->getType() : RHSExpr->getType(); 6446 ValueDependent = condEval.getZExtValue() ? LHSExpr->isValueDependent() 6447 : RHSExpr->isValueDependent(); 6448 } 6449 6450 cond.release(); expr1.release(); expr2.release(); 6451 return Owned(new (Context) ChooseExpr(BuiltinLoc, CondExpr, LHSExpr, RHSExpr, 6452 resType, RPLoc, 6453 resType->isDependentType(), 6454 ValueDependent)); 6455} 6456 6457//===----------------------------------------------------------------------===// 6458// Clang Extensions. 6459//===----------------------------------------------------------------------===// 6460 6461/// ActOnBlockStart - This callback is invoked when a block literal is started. 6462void Sema::ActOnBlockStart(SourceLocation CaretLoc, Scope *BlockScope) { 6463 // Analyze block parameters. 6464 BlockSemaInfo *BSI = new BlockSemaInfo(); 6465 6466 // Add BSI to CurBlock. 6467 BSI->PrevBlockInfo = CurBlock; 6468 CurBlock = BSI; 6469 6470 BSI->ReturnType = QualType(); 6471 BSI->TheScope = BlockScope; 6472 BSI->hasBlockDeclRefExprs = false; 6473 BSI->hasPrototype = false; 6474 BSI->SavedFunctionNeedsScopeChecking = CurFunctionNeedsScopeChecking; 6475 CurFunctionNeedsScopeChecking = false; 6476 6477 BSI->TheDecl = BlockDecl::Create(Context, CurContext, CaretLoc); 6478 PushDeclContext(BlockScope, BSI->TheDecl); 6479} 6480 6481void Sema::ActOnBlockArguments(Declarator &ParamInfo, Scope *CurScope) { 6482 assert(ParamInfo.getIdentifier()==0 && "block-id should have no identifier!"); 6483 6484 if (ParamInfo.getNumTypeObjects() == 0 6485 || ParamInfo.getTypeObject(0).Kind != DeclaratorChunk::Function) { 6486 ProcessDeclAttributes(CurScope, CurBlock->TheDecl, ParamInfo); 6487 QualType T = GetTypeForDeclarator(ParamInfo, CurScope); 6488 6489 if (T->isArrayType()) { 6490 Diag(ParamInfo.getSourceRange().getBegin(), 6491 diag::err_block_returns_array); 6492 return; 6493 } 6494 6495 // The parameter list is optional, if there was none, assume (). 6496 if (!T->isFunctionType()) 6497 T = Context.getFunctionType(T, NULL, 0, 0, 0); 6498 6499 CurBlock->hasPrototype = true; 6500 CurBlock->isVariadic = false; 6501 // Check for a valid sentinel attribute on this block. 6502 if (CurBlock->TheDecl->getAttr<SentinelAttr>()) { 6503 Diag(ParamInfo.getAttributes()->getLoc(), 6504 diag::warn_attribute_sentinel_not_variadic) << 1; 6505 // FIXME: remove the attribute. 6506 } 6507 QualType RetTy = T.getTypePtr()->getAs<FunctionType>()->getResultType(); 6508 6509 // Do not allow returning a objc interface by-value. 6510 if (RetTy->isObjCInterfaceType()) { 6511 Diag(ParamInfo.getSourceRange().getBegin(), 6512 diag::err_object_cannot_be_passed_returned_by_value) << 0 << RetTy; 6513 return; 6514 } 6515 return; 6516 } 6517 6518 // Analyze arguments to block. 6519 assert(ParamInfo.getTypeObject(0).Kind == DeclaratorChunk::Function && 6520 "Not a function declarator!"); 6521 DeclaratorChunk::FunctionTypeInfo &FTI = ParamInfo.getTypeObject(0).Fun; 6522 6523 CurBlock->hasPrototype = FTI.hasPrototype; 6524 CurBlock->isVariadic = true; 6525 6526 // Check for C99 6.7.5.3p10 - foo(void) is a non-varargs function that takes 6527 // no arguments, not a function that takes a single void argument. 6528 if (FTI.hasPrototype && 6529 FTI.NumArgs == 1 && !FTI.isVariadic && FTI.ArgInfo[0].Ident == 0 && 6530 (!FTI.ArgInfo[0].Param.getAs<ParmVarDecl>()->getType().getCVRQualifiers()&& 6531 FTI.ArgInfo[0].Param.getAs<ParmVarDecl>()->getType()->isVoidType())) { 6532 // empty arg list, don't push any params. 6533 CurBlock->isVariadic = false; 6534 } else if (FTI.hasPrototype) { 6535 for (unsigned i = 0, e = FTI.NumArgs; i != e; ++i) 6536 CurBlock->Params.push_back(FTI.ArgInfo[i].Param.getAs<ParmVarDecl>()); 6537 CurBlock->isVariadic = FTI.isVariadic; 6538 } 6539 CurBlock->TheDecl->setParams(Context, CurBlock->Params.data(), 6540 CurBlock->Params.size()); 6541 CurBlock->TheDecl->setIsVariadic(CurBlock->isVariadic); 6542 ProcessDeclAttributes(CurScope, CurBlock->TheDecl, ParamInfo); 6543 for (BlockDecl::param_iterator AI = CurBlock->TheDecl->param_begin(), 6544 E = CurBlock->TheDecl->param_end(); AI != E; ++AI) 6545 // If this has an identifier, add it to the scope stack. 6546 if ((*AI)->getIdentifier()) 6547 PushOnScopeChains(*AI, CurBlock->TheScope); 6548 6549 // Check for a valid sentinel attribute on this block. 6550 if (!CurBlock->isVariadic && 6551 CurBlock->TheDecl->getAttr<SentinelAttr>()) { 6552 Diag(ParamInfo.getAttributes()->getLoc(), 6553 diag::warn_attribute_sentinel_not_variadic) << 1; 6554 // FIXME: remove the attribute. 6555 } 6556 6557 // Analyze the return type. 6558 QualType T = GetTypeForDeclarator(ParamInfo, CurScope); 6559 QualType RetTy = T->getAs<FunctionType>()->getResultType(); 6560 6561 // Do not allow returning a objc interface by-value. 6562 if (RetTy->isObjCInterfaceType()) { 6563 Diag(ParamInfo.getSourceRange().getBegin(), 6564 diag::err_object_cannot_be_passed_returned_by_value) << 0 << RetTy; 6565 } else if (!RetTy->isDependentType()) 6566 CurBlock->ReturnType = RetTy; 6567} 6568 6569/// ActOnBlockError - If there is an error parsing a block, this callback 6570/// is invoked to pop the information about the block from the action impl. 6571void Sema::ActOnBlockError(SourceLocation CaretLoc, Scope *CurScope) { 6572 // Ensure that CurBlock is deleted. 6573 llvm::OwningPtr<BlockSemaInfo> CC(CurBlock); 6574 6575 CurFunctionNeedsScopeChecking = CurBlock->SavedFunctionNeedsScopeChecking; 6576 6577 // Pop off CurBlock, handle nested blocks. 6578 PopDeclContext(); 6579 CurBlock = CurBlock->PrevBlockInfo; 6580 // FIXME: Delete the ParmVarDecl objects as well??? 6581} 6582 6583/// ActOnBlockStmtExpr - This is called when the body of a block statement 6584/// literal was successfully completed. ^(int x){...} 6585Sema::OwningExprResult Sema::ActOnBlockStmtExpr(SourceLocation CaretLoc, 6586 StmtArg body, Scope *CurScope) { 6587 // If blocks are disabled, emit an error. 6588 if (!LangOpts.Blocks) 6589 Diag(CaretLoc, diag::err_blocks_disable); 6590 6591 // Ensure that CurBlock is deleted. 6592 llvm::OwningPtr<BlockSemaInfo> BSI(CurBlock); 6593 6594 PopDeclContext(); 6595 6596 // Pop off CurBlock, handle nested blocks. 6597 CurBlock = CurBlock->PrevBlockInfo; 6598 6599 QualType RetTy = Context.VoidTy; 6600 if (!BSI->ReturnType.isNull()) 6601 RetTy = BSI->ReturnType; 6602 6603 llvm::SmallVector<QualType, 8> ArgTypes; 6604 for (unsigned i = 0, e = BSI->Params.size(); i != e; ++i) 6605 ArgTypes.push_back(BSI->Params[i]->getType()); 6606 6607 bool NoReturn = BSI->TheDecl->getAttr<NoReturnAttr>(); 6608 QualType BlockTy; 6609 if (!BSI->hasPrototype) 6610 BlockTy = Context.getFunctionType(RetTy, 0, 0, false, 0, false, false, 0, 0, 6611 NoReturn); 6612 else 6613 BlockTy = Context.getFunctionType(RetTy, ArgTypes.data(), ArgTypes.size(), 6614 BSI->isVariadic, 0, false, false, 0, 0, 6615 NoReturn); 6616 6617 // FIXME: Check that return/parameter types are complete/non-abstract 6618 DiagnoseUnusedParameters(BSI->Params.begin(), BSI->Params.end()); 6619 BlockTy = Context.getBlockPointerType(BlockTy); 6620 6621 // If needed, diagnose invalid gotos and switches in the block. 6622 if (CurFunctionNeedsScopeChecking) 6623 DiagnoseInvalidJumps(static_cast<CompoundStmt*>(body.get())); 6624 CurFunctionNeedsScopeChecking = BSI->SavedFunctionNeedsScopeChecking; 6625 6626 BSI->TheDecl->setBody(body.takeAs<CompoundStmt>()); 6627 CheckFallThroughForBlock(BlockTy, BSI->TheDecl->getBody()); 6628 return Owned(new (Context) BlockExpr(BSI->TheDecl, BlockTy, 6629 BSI->hasBlockDeclRefExprs)); 6630} 6631 6632Sema::OwningExprResult Sema::ActOnVAArg(SourceLocation BuiltinLoc, 6633 ExprArg expr, TypeTy *type, 6634 SourceLocation RPLoc) { 6635 QualType T = GetTypeFromParser(type); 6636 Expr *E = static_cast<Expr*>(expr.get()); 6637 Expr *OrigExpr = E; 6638 6639 InitBuiltinVaListType(); 6640 6641 // Get the va_list type 6642 QualType VaListType = Context.getBuiltinVaListType(); 6643 if (VaListType->isArrayType()) { 6644 // Deal with implicit array decay; for example, on x86-64, 6645 // va_list is an array, but it's supposed to decay to 6646 // a pointer for va_arg. 6647 VaListType = Context.getArrayDecayedType(VaListType); 6648 // Make sure the input expression also decays appropriately. 6649 UsualUnaryConversions(E); 6650 } else { 6651 // Otherwise, the va_list argument must be an l-value because 6652 // it is modified by va_arg. 6653 if (!E->isTypeDependent() && 6654 CheckForModifiableLvalue(E, BuiltinLoc, *this)) 6655 return ExprError(); 6656 } 6657 6658 if (!E->isTypeDependent() && 6659 !Context.hasSameType(VaListType, E->getType())) { 6660 return ExprError(Diag(E->getLocStart(), 6661 diag::err_first_argument_to_va_arg_not_of_type_va_list) 6662 << OrigExpr->getType() << E->getSourceRange()); 6663 } 6664 6665 // FIXME: Check that type is complete/non-abstract 6666 // FIXME: Warn if a non-POD type is passed in. 6667 6668 expr.release(); 6669 return Owned(new (Context) VAArgExpr(BuiltinLoc, E, T.getNonReferenceType(), 6670 RPLoc)); 6671} 6672 6673Sema::OwningExprResult Sema::ActOnGNUNullExpr(SourceLocation TokenLoc) { 6674 // The type of __null will be int or long, depending on the size of 6675 // pointers on the target. 6676 QualType Ty; 6677 if (Context.Target.getPointerWidth(0) == Context.Target.getIntWidth()) 6678 Ty = Context.IntTy; 6679 else 6680 Ty = Context.LongTy; 6681 6682 return Owned(new (Context) GNUNullExpr(Ty, TokenLoc)); 6683} 6684 6685static void 6686MakeObjCStringLiteralCodeModificationHint(Sema& SemaRef, 6687 QualType DstType, 6688 Expr *SrcExpr, 6689 CodeModificationHint &Hint) { 6690 if (!SemaRef.getLangOptions().ObjC1) 6691 return; 6692 6693 const ObjCObjectPointerType *PT = DstType->getAs<ObjCObjectPointerType>(); 6694 if (!PT) 6695 return; 6696 6697 // Check if the destination is of type 'id'. 6698 if (!PT->isObjCIdType()) { 6699 // Check if the destination is the 'NSString' interface. 6700 const ObjCInterfaceDecl *ID = PT->getInterfaceDecl(); 6701 if (!ID || !ID->getIdentifier()->isStr("NSString")) 6702 return; 6703 } 6704 6705 // Strip off any parens and casts. 6706 StringLiteral *SL = dyn_cast<StringLiteral>(SrcExpr->IgnoreParenCasts()); 6707 if (!SL || SL->isWide()) 6708 return; 6709 6710 Hint = CodeModificationHint::CreateInsertion(SL->getLocStart(), "@"); 6711} 6712 6713bool Sema::DiagnoseAssignmentResult(AssignConvertType ConvTy, 6714 SourceLocation Loc, 6715 QualType DstType, QualType SrcType, 6716 Expr *SrcExpr, const char *Flavor) { 6717 // Decode the result (notice that AST's are still created for extensions). 6718 bool isInvalid = false; 6719 unsigned DiagKind; 6720 CodeModificationHint Hint; 6721 6722 switch (ConvTy) { 6723 default: assert(0 && "Unknown conversion type"); 6724 case Compatible: return false; 6725 case PointerToInt: 6726 DiagKind = diag::ext_typecheck_convert_pointer_int; 6727 break; 6728 case IntToPointer: 6729 DiagKind = diag::ext_typecheck_convert_int_pointer; 6730 break; 6731 case IncompatiblePointer: 6732 MakeObjCStringLiteralCodeModificationHint(*this, DstType, SrcExpr, Hint); 6733 DiagKind = diag::ext_typecheck_convert_incompatible_pointer; 6734 break; 6735 case IncompatiblePointerSign: 6736 DiagKind = diag::ext_typecheck_convert_incompatible_pointer_sign; 6737 break; 6738 case FunctionVoidPointer: 6739 DiagKind = diag::ext_typecheck_convert_pointer_void_func; 6740 break; 6741 case CompatiblePointerDiscardsQualifiers: 6742 // If the qualifiers lost were because we were applying the 6743 // (deprecated) C++ conversion from a string literal to a char* 6744 // (or wchar_t*), then there was no error (C++ 4.2p2). FIXME: 6745 // Ideally, this check would be performed in 6746 // CheckPointerTypesForAssignment. However, that would require a 6747 // bit of refactoring (so that the second argument is an 6748 // expression, rather than a type), which should be done as part 6749 // of a larger effort to fix CheckPointerTypesForAssignment for 6750 // C++ semantics. 6751 if (getLangOptions().CPlusPlus && 6752 IsStringLiteralToNonConstPointerConversion(SrcExpr, DstType)) 6753 return false; 6754 DiagKind = diag::ext_typecheck_convert_discards_qualifiers; 6755 break; 6756 case IncompatibleNestedPointerQualifiers: 6757 DiagKind = diag::ext_nested_pointer_qualifier_mismatch; 6758 break; 6759 case IntToBlockPointer: 6760 DiagKind = diag::err_int_to_block_pointer; 6761 break; 6762 case IncompatibleBlockPointer: 6763 DiagKind = diag::err_typecheck_convert_incompatible_block_pointer; 6764 break; 6765 case IncompatibleObjCQualifiedId: 6766 // FIXME: Diagnose the problem in ObjCQualifiedIdTypesAreCompatible, since 6767 // it can give a more specific diagnostic. 6768 DiagKind = diag::warn_incompatible_qualified_id; 6769 break; 6770 case IncompatibleVectors: 6771 DiagKind = diag::warn_incompatible_vectors; 6772 break; 6773 case Incompatible: 6774 DiagKind = diag::err_typecheck_convert_incompatible; 6775 isInvalid = true; 6776 break; 6777 } 6778 6779 Diag(Loc, DiagKind) << DstType << SrcType << Flavor 6780 << SrcExpr->getSourceRange() << Hint; 6781 return isInvalid; 6782} 6783 6784bool Sema::VerifyIntegerConstantExpression(const Expr *E, llvm::APSInt *Result){ 6785 llvm::APSInt ICEResult; 6786 if (E->isIntegerConstantExpr(ICEResult, Context)) { 6787 if (Result) 6788 *Result = ICEResult; 6789 return false; 6790 } 6791 6792 Expr::EvalResult EvalResult; 6793 6794 if (!E->Evaluate(EvalResult, Context) || !EvalResult.Val.isInt() || 6795 EvalResult.HasSideEffects) { 6796 Diag(E->getExprLoc(), diag::err_expr_not_ice) << E->getSourceRange(); 6797 6798 if (EvalResult.Diag) { 6799 // We only show the note if it's not the usual "invalid subexpression" 6800 // or if it's actually in a subexpression. 6801 if (EvalResult.Diag != diag::note_invalid_subexpr_in_ice || 6802 E->IgnoreParens() != EvalResult.DiagExpr->IgnoreParens()) 6803 Diag(EvalResult.DiagLoc, EvalResult.Diag); 6804 } 6805 6806 return true; 6807 } 6808 6809 Diag(E->getExprLoc(), diag::ext_expr_not_ice) << 6810 E->getSourceRange(); 6811 6812 if (EvalResult.Diag && 6813 Diags.getDiagnosticLevel(diag::ext_expr_not_ice) != Diagnostic::Ignored) 6814 Diag(EvalResult.DiagLoc, EvalResult.Diag); 6815 6816 if (Result) 6817 *Result = EvalResult.Val.getInt(); 6818 return false; 6819} 6820 6821void 6822Sema::PushExpressionEvaluationContext(ExpressionEvaluationContext NewContext) { 6823 ExprEvalContexts.push_back( 6824 ExpressionEvaluationContextRecord(NewContext, ExprTemporaries.size())); 6825} 6826 6827void 6828Sema::PopExpressionEvaluationContext() { 6829 // Pop the current expression evaluation context off the stack. 6830 ExpressionEvaluationContextRecord Rec = ExprEvalContexts.back(); 6831 ExprEvalContexts.pop_back(); 6832 6833 if (Rec.Context == PotentiallyPotentiallyEvaluated && 6834 Rec.PotentiallyReferenced) { 6835 // Mark any remaining declarations in the current position of the stack 6836 // as "referenced". If they were not meant to be referenced, semantic 6837 // analysis would have eliminated them (e.g., in ActOnCXXTypeId). 6838 for (PotentiallyReferencedDecls::iterator 6839 I = Rec.PotentiallyReferenced->begin(), 6840 IEnd = Rec.PotentiallyReferenced->end(); 6841 I != IEnd; ++I) 6842 MarkDeclarationReferenced(I->first, I->second); 6843 } 6844 6845 // When are coming out of an unevaluated context, clear out any 6846 // temporaries that we may have created as part of the evaluation of 6847 // the expression in that context: they aren't relevant because they 6848 // will never be constructed. 6849 if (Rec.Context == Unevaluated && 6850 ExprTemporaries.size() > Rec.NumTemporaries) 6851 ExprTemporaries.erase(ExprTemporaries.begin() + Rec.NumTemporaries, 6852 ExprTemporaries.end()); 6853 6854 // Destroy the popped expression evaluation record. 6855 Rec.Destroy(); 6856} 6857 6858/// \brief Note that the given declaration was referenced in the source code. 6859/// 6860/// This routine should be invoke whenever a given declaration is referenced 6861/// in the source code, and where that reference occurred. If this declaration 6862/// reference means that the the declaration is used (C++ [basic.def.odr]p2, 6863/// C99 6.9p3), then the declaration will be marked as used. 6864/// 6865/// \param Loc the location where the declaration was referenced. 6866/// 6867/// \param D the declaration that has been referenced by the source code. 6868void Sema::MarkDeclarationReferenced(SourceLocation Loc, Decl *D) { 6869 assert(D && "No declaration?"); 6870 6871 if (D->isUsed()) 6872 return; 6873 6874 // Mark a parameter or variable declaration "used", regardless of whether we're in a 6875 // template or not. The reason for this is that unevaluated expressions 6876 // (e.g. (void)sizeof()) constitute a use for warning purposes (-Wunused-variables and 6877 // -Wunused-parameters) 6878 if (isa<ParmVarDecl>(D) || 6879 (isa<VarDecl>(D) && D->getDeclContext()->isFunctionOrMethod())) 6880 D->setUsed(true); 6881 6882 // Do not mark anything as "used" within a dependent context; wait for 6883 // an instantiation. 6884 if (CurContext->isDependentContext()) 6885 return; 6886 6887 switch (ExprEvalContexts.back().Context) { 6888 case Unevaluated: 6889 // We are in an expression that is not potentially evaluated; do nothing. 6890 return; 6891 6892 case PotentiallyEvaluated: 6893 // We are in a potentially-evaluated expression, so this declaration is 6894 // "used"; handle this below. 6895 break; 6896 6897 case PotentiallyPotentiallyEvaluated: 6898 // We are in an expression that may be potentially evaluated; queue this 6899 // declaration reference until we know whether the expression is 6900 // potentially evaluated. 6901 ExprEvalContexts.back().addReferencedDecl(Loc, D); 6902 return; 6903 } 6904 6905 // Note that this declaration has been used. 6906 if (CXXConstructorDecl *Constructor = dyn_cast<CXXConstructorDecl>(D)) { 6907 unsigned TypeQuals; 6908 if (Constructor->isImplicit() && Constructor->isDefaultConstructor()) { 6909 if (!Constructor->isUsed()) 6910 DefineImplicitDefaultConstructor(Loc, Constructor); 6911 } else if (Constructor->isImplicit() && 6912 Constructor->isCopyConstructor(Context, TypeQuals)) { 6913 if (!Constructor->isUsed()) 6914 DefineImplicitCopyConstructor(Loc, Constructor, TypeQuals); 6915 } 6916 } else if (CXXDestructorDecl *Destructor = dyn_cast<CXXDestructorDecl>(D)) { 6917 if (Destructor->isImplicit() && !Destructor->isUsed()) 6918 DefineImplicitDestructor(Loc, Destructor); 6919 6920 } else if (CXXMethodDecl *MethodDecl = dyn_cast<CXXMethodDecl>(D)) { 6921 if (MethodDecl->isImplicit() && MethodDecl->isOverloadedOperator() && 6922 MethodDecl->getOverloadedOperator() == OO_Equal) { 6923 if (!MethodDecl->isUsed()) 6924 DefineImplicitOverloadedAssign(Loc, MethodDecl); 6925 } 6926 } 6927 if (FunctionDecl *Function = dyn_cast<FunctionDecl>(D)) { 6928 // Implicit instantiation of function templates and member functions of 6929 // class templates. 6930 if (!Function->getBody() && Function->isImplicitlyInstantiable()) { 6931 bool AlreadyInstantiated = false; 6932 if (FunctionTemplateSpecializationInfo *SpecInfo 6933 = Function->getTemplateSpecializationInfo()) { 6934 if (SpecInfo->getPointOfInstantiation().isInvalid()) 6935 SpecInfo->setPointOfInstantiation(Loc); 6936 else if (SpecInfo->getTemplateSpecializationKind() 6937 == TSK_ImplicitInstantiation) 6938 AlreadyInstantiated = true; 6939 } else if (MemberSpecializationInfo *MSInfo 6940 = Function->getMemberSpecializationInfo()) { 6941 if (MSInfo->getPointOfInstantiation().isInvalid()) 6942 MSInfo->setPointOfInstantiation(Loc); 6943 else if (MSInfo->getTemplateSpecializationKind() 6944 == TSK_ImplicitInstantiation) 6945 AlreadyInstantiated = true; 6946 } 6947 6948 if (!AlreadyInstantiated) 6949 PendingImplicitInstantiations.push_back(std::make_pair(Function, Loc)); 6950 } 6951 6952 // FIXME: keep track of references to static functions 6953 Function->setUsed(true); 6954 return; 6955 } 6956 6957 if (VarDecl *Var = dyn_cast<VarDecl>(D)) { 6958 // Implicit instantiation of static data members of class templates. 6959 if (Var->isStaticDataMember() && 6960 Var->getInstantiatedFromStaticDataMember()) { 6961 MemberSpecializationInfo *MSInfo = Var->getMemberSpecializationInfo(); 6962 assert(MSInfo && "Missing member specialization information?"); 6963 if (MSInfo->getPointOfInstantiation().isInvalid() && 6964 MSInfo->getTemplateSpecializationKind()== TSK_ImplicitInstantiation) { 6965 MSInfo->setPointOfInstantiation(Loc); 6966 PendingImplicitInstantiations.push_back(std::make_pair(Var, Loc)); 6967 } 6968 } 6969 6970 // FIXME: keep track of references to static data? 6971 6972 D->setUsed(true); 6973 return; 6974 } 6975} 6976 6977bool Sema::CheckCallReturnType(QualType ReturnType, SourceLocation Loc, 6978 CallExpr *CE, FunctionDecl *FD) { 6979 if (ReturnType->isVoidType() || !ReturnType->isIncompleteType()) 6980 return false; 6981 6982 PartialDiagnostic Note = 6983 FD ? PDiag(diag::note_function_with_incomplete_return_type_declared_here) 6984 << FD->getDeclName() : PDiag(); 6985 SourceLocation NoteLoc = FD ? FD->getLocation() : SourceLocation(); 6986 6987 if (RequireCompleteType(Loc, ReturnType, 6988 FD ? 6989 PDiag(diag::err_call_function_incomplete_return) 6990 << CE->getSourceRange() << FD->getDeclName() : 6991 PDiag(diag::err_call_incomplete_return) 6992 << CE->getSourceRange(), 6993 std::make_pair(NoteLoc, Note))) 6994 return true; 6995 6996 return false; 6997} 6998 6999// Diagnose the common s/=/==/ typo. Note that adding parentheses 7000// will prevent this condition from triggering, which is what we want. 7001void Sema::DiagnoseAssignmentAsCondition(Expr *E) { 7002 SourceLocation Loc; 7003 7004 unsigned diagnostic = diag::warn_condition_is_assignment; 7005 7006 if (isa<BinaryOperator>(E)) { 7007 BinaryOperator *Op = cast<BinaryOperator>(E); 7008 if (Op->getOpcode() != BinaryOperator::Assign) 7009 return; 7010 7011 // Greylist some idioms by putting them into a warning subcategory. 7012 if (ObjCMessageExpr *ME 7013 = dyn_cast<ObjCMessageExpr>(Op->getRHS()->IgnoreParenCasts())) { 7014 Selector Sel = ME->getSelector(); 7015 7016 // self = [<foo> init...] 7017 if (isSelfExpr(Op->getLHS()) 7018 && Sel.getIdentifierInfoForSlot(0)->getName().startswith("init")) 7019 diagnostic = diag::warn_condition_is_idiomatic_assignment; 7020 7021 // <foo> = [<bar> nextObject] 7022 else if (Sel.isUnarySelector() && 7023 Sel.getIdentifierInfoForSlot(0)->getName() == "nextObject") 7024 diagnostic = diag::warn_condition_is_idiomatic_assignment; 7025 } 7026 7027 Loc = Op->getOperatorLoc(); 7028 } else if (isa<CXXOperatorCallExpr>(E)) { 7029 CXXOperatorCallExpr *Op = cast<CXXOperatorCallExpr>(E); 7030 if (Op->getOperator() != OO_Equal) 7031 return; 7032 7033 Loc = Op->getOperatorLoc(); 7034 } else { 7035 // Not an assignment. 7036 return; 7037 } 7038 7039 SourceLocation Open = E->getSourceRange().getBegin(); 7040 SourceLocation Close = PP.getLocForEndOfToken(E->getSourceRange().getEnd()); 7041 7042 Diag(Loc, diagnostic) 7043 << E->getSourceRange() 7044 << CodeModificationHint::CreateInsertion(Open, "(") 7045 << CodeModificationHint::CreateInsertion(Close, ")"); 7046} 7047 7048bool Sema::CheckBooleanCondition(Expr *&E, SourceLocation Loc) { 7049 DiagnoseAssignmentAsCondition(E); 7050 7051 if (!E->isTypeDependent()) { 7052 DefaultFunctionArrayConversion(E); 7053 7054 QualType T = E->getType(); 7055 7056 if (getLangOptions().CPlusPlus) { 7057 if (CheckCXXBooleanCondition(E)) // C++ 6.4p4 7058 return true; 7059 } else if (!T->isScalarType()) { // C99 6.8.4.1p1 7060 Diag(Loc, diag::err_typecheck_statement_requires_scalar) 7061 << T << E->getSourceRange(); 7062 return true; 7063 } 7064 } 7065 7066 return false; 7067} 7068