SemaExpr.cpp revision 32c627e217b55256110f5d7adfd6bff6dd33169a
1//===--- SemaExpr.cpp - Semantic Analysis for Expressions -----------------===// 2// 3// The LLVM Compiler Infrastructure 4// 5// This file is distributed under the University of Illinois Open Source 6// License. See LICENSE.TXT for details. 7// 8//===----------------------------------------------------------------------===// 9// 10// This file implements semantic analysis for expressions. 11// 12//===----------------------------------------------------------------------===// 13 14#include "Sema.h" 15#include "SemaInit.h" 16#include "Lookup.h" 17#include "clang/Analysis/AnalysisContext.h" 18#include "clang/AST/ASTContext.h" 19#include "clang/AST/DeclObjC.h" 20#include "clang/AST/DeclTemplate.h" 21#include "clang/AST/ExprCXX.h" 22#include "clang/AST/ExprObjC.h" 23#include "clang/Basic/PartialDiagnostic.h" 24#include "clang/Basic/SourceManager.h" 25#include "clang/Basic/TargetInfo.h" 26#include "clang/Lex/LiteralSupport.h" 27#include "clang/Lex/Preprocessor.h" 28#include "clang/Parse/DeclSpec.h" 29#include "clang/Parse/Designator.h" 30#include "clang/Parse/Scope.h" 31#include "clang/Parse/Template.h" 32using namespace clang; 33 34 35/// \brief Determine whether the use of this declaration is valid, and 36/// emit any corresponding diagnostics. 37/// 38/// This routine diagnoses various problems with referencing 39/// declarations that can occur when using a declaration. For example, 40/// it might warn if a deprecated or unavailable declaration is being 41/// used, or produce an error (and return true) if a C++0x deleted 42/// function is being used. 43/// 44/// If IgnoreDeprecated is set to true, this should not want about deprecated 45/// decls. 46/// 47/// \returns true if there was an error (this declaration cannot be 48/// referenced), false otherwise. 49/// 50bool Sema::DiagnoseUseOfDecl(NamedDecl *D, SourceLocation Loc) { 51 // See if the decl is deprecated. 52 if (D->getAttr<DeprecatedAttr>()) { 53 EmitDeprecationWarning(D, Loc); 54 } 55 56 // See if the decl is unavailable 57 if (D->getAttr<UnavailableAttr>()) { 58 Diag(Loc, diag::warn_unavailable) << D->getDeclName(); 59 Diag(D->getLocation(), diag::note_unavailable_here) << 0; 60 } 61 62 // See if this is a deleted function. 63 if (FunctionDecl *FD = dyn_cast<FunctionDecl>(D)) { 64 if (FD->isDeleted()) { 65 Diag(Loc, diag::err_deleted_function_use); 66 Diag(D->getLocation(), diag::note_unavailable_here) << true; 67 return true; 68 } 69 } 70 71 return false; 72} 73 74/// DiagnoseSentinelCalls - This routine checks on method dispatch calls 75/// (and other functions in future), which have been declared with sentinel 76/// attribute. It warns if call does not have the sentinel argument. 77/// 78void Sema::DiagnoseSentinelCalls(NamedDecl *D, SourceLocation Loc, 79 Expr **Args, unsigned NumArgs) { 80 const SentinelAttr *attr = D->getAttr<SentinelAttr>(); 81 if (!attr) 82 return; 83 int sentinelPos = attr->getSentinel(); 84 int nullPos = attr->getNullPos(); 85 86 // FIXME. ObjCMethodDecl and FunctionDecl need be derived from the same common 87 // base class. Then we won't be needing two versions of the same code. 88 unsigned int i = 0; 89 bool warnNotEnoughArgs = false; 90 int isMethod = 0; 91 if (ObjCMethodDecl *MD = dyn_cast<ObjCMethodDecl>(D)) { 92 // skip over named parameters. 93 ObjCMethodDecl::param_iterator P, E = MD->param_end(); 94 for (P = MD->param_begin(); (P != E && i < NumArgs); ++P) { 95 if (nullPos) 96 --nullPos; 97 else 98 ++i; 99 } 100 warnNotEnoughArgs = (P != E || i >= NumArgs); 101 isMethod = 1; 102 } else if (FunctionDecl *FD = dyn_cast<FunctionDecl>(D)) { 103 // skip over named parameters. 104 ObjCMethodDecl::param_iterator P, E = FD->param_end(); 105 for (P = FD->param_begin(); (P != E && i < NumArgs); ++P) { 106 if (nullPos) 107 --nullPos; 108 else 109 ++i; 110 } 111 warnNotEnoughArgs = (P != E || i >= NumArgs); 112 } else if (VarDecl *V = dyn_cast<VarDecl>(D)) { 113 // block or function pointer call. 114 QualType Ty = V->getType(); 115 if (Ty->isBlockPointerType() || Ty->isFunctionPointerType()) { 116 const FunctionType *FT = Ty->isFunctionPointerType() 117 ? Ty->getAs<PointerType>()->getPointeeType()->getAs<FunctionType>() 118 : Ty->getAs<BlockPointerType>()->getPointeeType()->getAs<FunctionType>(); 119 if (const FunctionProtoType *Proto = dyn_cast<FunctionProtoType>(FT)) { 120 unsigned NumArgsInProto = Proto->getNumArgs(); 121 unsigned k; 122 for (k = 0; (k != NumArgsInProto && i < NumArgs); k++) { 123 if (nullPos) 124 --nullPos; 125 else 126 ++i; 127 } 128 warnNotEnoughArgs = (k != NumArgsInProto || i >= NumArgs); 129 } 130 if (Ty->isBlockPointerType()) 131 isMethod = 2; 132 } else 133 return; 134 } else 135 return; 136 137 if (warnNotEnoughArgs) { 138 Diag(Loc, diag::warn_not_enough_argument) << D->getDeclName(); 139 Diag(D->getLocation(), diag::note_sentinel_here) << isMethod; 140 return; 141 } 142 int sentinel = i; 143 while (sentinelPos > 0 && i < NumArgs-1) { 144 --sentinelPos; 145 ++i; 146 } 147 if (sentinelPos > 0) { 148 Diag(Loc, diag::warn_not_enough_argument) << D->getDeclName(); 149 Diag(D->getLocation(), diag::note_sentinel_here) << isMethod; 150 return; 151 } 152 while (i < NumArgs-1) { 153 ++i; 154 ++sentinel; 155 } 156 Expr *sentinelExpr = Args[sentinel]; 157 if (sentinelExpr && (!isa<GNUNullExpr>(sentinelExpr) && 158 (!sentinelExpr->getType()->isPointerType() || 159 !sentinelExpr->isNullPointerConstant(Context, 160 Expr::NPC_ValueDependentIsNull)))) { 161 Diag(Loc, diag::warn_missing_sentinel) << isMethod; 162 Diag(D->getLocation(), diag::note_sentinel_here) << isMethod; 163 } 164 return; 165} 166 167SourceRange Sema::getExprRange(ExprTy *E) const { 168 Expr *Ex = (Expr *)E; 169 return Ex? Ex->getSourceRange() : SourceRange(); 170} 171 172//===----------------------------------------------------------------------===// 173// Standard Promotions and Conversions 174//===----------------------------------------------------------------------===// 175 176/// DefaultFunctionArrayConversion (C99 6.3.2.1p3, C99 6.3.2.1p4). 177void Sema::DefaultFunctionArrayConversion(Expr *&E) { 178 QualType Ty = E->getType(); 179 assert(!Ty.isNull() && "DefaultFunctionArrayConversion - missing type"); 180 181 if (Ty->isFunctionType()) 182 ImpCastExprToType(E, Context.getPointerType(Ty), 183 CastExpr::CK_FunctionToPointerDecay); 184 else if (Ty->isArrayType()) { 185 // In C90 mode, arrays only promote to pointers if the array expression is 186 // an lvalue. The relevant legalese is C90 6.2.2.1p3: "an lvalue that has 187 // type 'array of type' is converted to an expression that has type 'pointer 188 // to type'...". In C99 this was changed to: C99 6.3.2.1p3: "an expression 189 // that has type 'array of type' ...". The relevant change is "an lvalue" 190 // (C90) to "an expression" (C99). 191 // 192 // C++ 4.2p1: 193 // An lvalue or rvalue of type "array of N T" or "array of unknown bound of 194 // T" can be converted to an rvalue of type "pointer to T". 195 // 196 if (getLangOptions().C99 || getLangOptions().CPlusPlus || 197 E->isLvalue(Context) == Expr::LV_Valid) 198 ImpCastExprToType(E, Context.getArrayDecayedType(Ty), 199 CastExpr::CK_ArrayToPointerDecay); 200 } 201} 202 203void Sema::DefaultFunctionArrayLvalueConversion(Expr *&E) { 204 DefaultFunctionArrayConversion(E); 205 206 QualType Ty = E->getType(); 207 assert(!Ty.isNull() && "DefaultFunctionArrayLvalueConversion - missing type"); 208 if (!Ty->isDependentType() && Ty.hasQualifiers() && 209 (!getLangOptions().CPlusPlus || !Ty->isRecordType()) && 210 E->isLvalue(Context) == Expr::LV_Valid) { 211 // C++ [conv.lval]p1: 212 // [...] If T is a non-class type, the type of the rvalue is the 213 // cv-unqualified version of T. Otherwise, the type of the 214 // rvalue is T 215 // 216 // C99 6.3.2.1p2: 217 // If the lvalue has qualified type, the value has the unqualified 218 // version of the type of the lvalue; otherwise, the value has the 219 // type of the lvalue. 220 ImpCastExprToType(E, Ty.getUnqualifiedType(), CastExpr::CK_NoOp); 221 } 222} 223 224 225/// UsualUnaryConversions - Performs various conversions that are common to most 226/// operators (C99 6.3). The conversions of array and function types are 227/// sometimes surpressed. For example, the array->pointer conversion doesn't 228/// apply if the array is an argument to the sizeof or address (&) operators. 229/// In these instances, this routine should *not* be called. 230Expr *Sema::UsualUnaryConversions(Expr *&Expr) { 231 QualType Ty = Expr->getType(); 232 assert(!Ty.isNull() && "UsualUnaryConversions - missing type"); 233 234 // C99 6.3.1.1p2: 235 // 236 // The following may be used in an expression wherever an int or 237 // unsigned int may be used: 238 // - an object or expression with an integer type whose integer 239 // conversion rank is less than or equal to the rank of int 240 // and unsigned int. 241 // - A bit-field of type _Bool, int, signed int, or unsigned int. 242 // 243 // If an int can represent all values of the original type, the 244 // value is converted to an int; otherwise, it is converted to an 245 // unsigned int. These are called the integer promotions. All 246 // other types are unchanged by the integer promotions. 247 QualType PTy = Context.isPromotableBitField(Expr); 248 if (!PTy.isNull()) { 249 ImpCastExprToType(Expr, PTy, CastExpr::CK_IntegralCast); 250 return Expr; 251 } 252 if (Ty->isPromotableIntegerType()) { 253 QualType PT = Context.getPromotedIntegerType(Ty); 254 ImpCastExprToType(Expr, PT, CastExpr::CK_IntegralCast); 255 return Expr; 256 } 257 258 DefaultFunctionArrayLvalueConversion(Expr); 259 return Expr; 260} 261 262/// DefaultArgumentPromotion (C99 6.5.2.2p6). Used for function calls that 263/// do not have a prototype. Arguments that have type float are promoted to 264/// double. All other argument types are converted by UsualUnaryConversions(). 265void Sema::DefaultArgumentPromotion(Expr *&Expr) { 266 QualType Ty = Expr->getType(); 267 assert(!Ty.isNull() && "DefaultArgumentPromotion - missing type"); 268 269 // If this is a 'float' (CVR qualified or typedef) promote to double. 270 if (const BuiltinType *BT = Ty->getAs<BuiltinType>()) 271 if (BT->getKind() == BuiltinType::Float) 272 return ImpCastExprToType(Expr, Context.DoubleTy, 273 CastExpr::CK_FloatingCast); 274 275 UsualUnaryConversions(Expr); 276} 277 278/// DefaultVariadicArgumentPromotion - Like DefaultArgumentPromotion, but 279/// will warn if the resulting type is not a POD type, and rejects ObjC 280/// interfaces passed by value. This returns true if the argument type is 281/// completely illegal. 282bool Sema::DefaultVariadicArgumentPromotion(Expr *&Expr, VariadicCallType CT) { 283 DefaultArgumentPromotion(Expr); 284 285 if (Expr->getType()->isObjCInterfaceType() && 286 DiagRuntimeBehavior(Expr->getLocStart(), 287 PDiag(diag::err_cannot_pass_objc_interface_to_vararg) 288 << Expr->getType() << CT)) 289 return true; 290 291 if (!Expr->getType()->isPODType() && 292 DiagRuntimeBehavior(Expr->getLocStart(), 293 PDiag(diag::warn_cannot_pass_non_pod_arg_to_vararg) 294 << Expr->getType() << CT)) 295 return true; 296 297 return false; 298} 299 300 301/// UsualArithmeticConversions - Performs various conversions that are common to 302/// binary operators (C99 6.3.1.8). If both operands aren't arithmetic, this 303/// routine returns the first non-arithmetic type found. The client is 304/// responsible for emitting appropriate error diagnostics. 305/// FIXME: verify the conversion rules for "complex int" are consistent with 306/// GCC. 307QualType Sema::UsualArithmeticConversions(Expr *&lhsExpr, Expr *&rhsExpr, 308 bool isCompAssign) { 309 if (!isCompAssign) 310 UsualUnaryConversions(lhsExpr); 311 312 UsualUnaryConversions(rhsExpr); 313 314 // For conversion purposes, we ignore any qualifiers. 315 // For example, "const float" and "float" are equivalent. 316 QualType lhs = 317 Context.getCanonicalType(lhsExpr->getType()).getUnqualifiedType(); 318 QualType rhs = 319 Context.getCanonicalType(rhsExpr->getType()).getUnqualifiedType(); 320 321 // If both types are identical, no conversion is needed. 322 if (lhs == rhs) 323 return lhs; 324 325 // If either side is a non-arithmetic type (e.g. a pointer), we are done. 326 // The caller can deal with this (e.g. pointer + int). 327 if (!lhs->isArithmeticType() || !rhs->isArithmeticType()) 328 return lhs; 329 330 // Perform bitfield promotions. 331 QualType LHSBitfieldPromoteTy = Context.isPromotableBitField(lhsExpr); 332 if (!LHSBitfieldPromoteTy.isNull()) 333 lhs = LHSBitfieldPromoteTy; 334 QualType RHSBitfieldPromoteTy = Context.isPromotableBitField(rhsExpr); 335 if (!RHSBitfieldPromoteTy.isNull()) 336 rhs = RHSBitfieldPromoteTy; 337 338 QualType destType = Context.UsualArithmeticConversionsType(lhs, rhs); 339 if (!isCompAssign) 340 ImpCastExprToType(lhsExpr, destType, CastExpr::CK_Unknown); 341 ImpCastExprToType(rhsExpr, destType, CastExpr::CK_Unknown); 342 return destType; 343} 344 345//===----------------------------------------------------------------------===// 346// Semantic Analysis for various Expression Types 347//===----------------------------------------------------------------------===// 348 349 350/// ActOnStringLiteral - The specified tokens were lexed as pasted string 351/// fragments (e.g. "foo" "bar" L"baz"). The result string has to handle string 352/// concatenation ([C99 5.1.1.2, translation phase #6]), so it may come from 353/// multiple tokens. However, the common case is that StringToks points to one 354/// string. 355/// 356Action::OwningExprResult 357Sema::ActOnStringLiteral(const Token *StringToks, unsigned NumStringToks) { 358 assert(NumStringToks && "Must have at least one string!"); 359 360 StringLiteralParser Literal(StringToks, NumStringToks, PP); 361 if (Literal.hadError) 362 return ExprError(); 363 364 llvm::SmallVector<SourceLocation, 4> StringTokLocs; 365 for (unsigned i = 0; i != NumStringToks; ++i) 366 StringTokLocs.push_back(StringToks[i].getLocation()); 367 368 QualType StrTy = Context.CharTy; 369 if (Literal.AnyWide) StrTy = Context.getWCharType(); 370 if (Literal.Pascal) StrTy = Context.UnsignedCharTy; 371 372 // A C++ string literal has a const-qualified element type (C++ 2.13.4p1). 373 if (getLangOptions().CPlusPlus) 374 StrTy.addConst(); 375 376 // Get an array type for the string, according to C99 6.4.5. This includes 377 // the nul terminator character as well as the string length for pascal 378 // strings. 379 StrTy = Context.getConstantArrayType(StrTy, 380 llvm::APInt(32, Literal.GetNumStringChars()+1), 381 ArrayType::Normal, 0); 382 383 // Pass &StringTokLocs[0], StringTokLocs.size() to factory! 384 return Owned(StringLiteral::Create(Context, Literal.GetString(), 385 Literal.GetStringLength(), 386 Literal.AnyWide, StrTy, 387 &StringTokLocs[0], 388 StringTokLocs.size())); 389} 390 391/// ShouldSnapshotBlockValueReference - Return true if a reference inside of 392/// CurBlock to VD should cause it to be snapshotted (as we do for auto 393/// variables defined outside the block) or false if this is not needed (e.g. 394/// for values inside the block or for globals). 395/// 396/// This also keeps the 'hasBlockDeclRefExprs' in the BlockSemaInfo records 397/// up-to-date. 398/// 399static bool ShouldSnapshotBlockValueReference(BlockSemaInfo *CurBlock, 400 ValueDecl *VD) { 401 // If the value is defined inside the block, we couldn't snapshot it even if 402 // we wanted to. 403 if (CurBlock->TheDecl == VD->getDeclContext()) 404 return false; 405 406 // If this is an enum constant or function, it is constant, don't snapshot. 407 if (isa<EnumConstantDecl>(VD) || isa<FunctionDecl>(VD)) 408 return false; 409 410 // If this is a reference to an extern, static, or global variable, no need to 411 // snapshot it. 412 // FIXME: What about 'const' variables in C++? 413 if (const VarDecl *Var = dyn_cast<VarDecl>(VD)) 414 if (!Var->hasLocalStorage()) 415 return false; 416 417 // Blocks that have these can't be constant. 418 CurBlock->hasBlockDeclRefExprs = true; 419 420 // If we have nested blocks, the decl may be declared in an outer block (in 421 // which case that outer block doesn't get "hasBlockDeclRefExprs") or it may 422 // be defined outside all of the current blocks (in which case the blocks do 423 // all get the bit). Walk the nesting chain. 424 for (BlockSemaInfo *NextBlock = CurBlock->PrevBlockInfo; NextBlock; 425 NextBlock = NextBlock->PrevBlockInfo) { 426 // If we found the defining block for the variable, don't mark the block as 427 // having a reference outside it. 428 if (NextBlock->TheDecl == VD->getDeclContext()) 429 break; 430 431 // Otherwise, the DeclRef from the inner block causes the outer one to need 432 // a snapshot as well. 433 NextBlock->hasBlockDeclRefExprs = true; 434 } 435 436 return true; 437} 438 439 440 441/// BuildDeclRefExpr - Build a DeclRefExpr. 442Sema::OwningExprResult 443Sema::BuildDeclRefExpr(ValueDecl *D, QualType Ty, SourceLocation Loc, 444 const CXXScopeSpec *SS) { 445 if (Context.getCanonicalType(Ty) == Context.UndeducedAutoTy) { 446 Diag(Loc, 447 diag::err_auto_variable_cannot_appear_in_own_initializer) 448 << D->getDeclName(); 449 return ExprError(); 450 } 451 452 if (const VarDecl *VD = dyn_cast<VarDecl>(D)) { 453 if (const CXXMethodDecl *MD = dyn_cast<CXXMethodDecl>(CurContext)) { 454 if (const FunctionDecl *FD = MD->getParent()->isLocalClass()) { 455 if (VD->hasLocalStorage() && VD->getDeclContext() != CurContext) { 456 Diag(Loc, diag::err_reference_to_local_var_in_enclosing_function) 457 << D->getIdentifier() << FD->getDeclName(); 458 Diag(D->getLocation(), diag::note_local_variable_declared_here) 459 << D->getIdentifier(); 460 return ExprError(); 461 } 462 } 463 } 464 } 465 466 MarkDeclarationReferenced(Loc, D); 467 468 return Owned(DeclRefExpr::Create(Context, 469 SS? (NestedNameSpecifier *)SS->getScopeRep() : 0, 470 SS? SS->getRange() : SourceRange(), 471 D, Loc, Ty)); 472} 473 474/// getObjectForAnonymousRecordDecl - Retrieve the (unnamed) field or 475/// variable corresponding to the anonymous union or struct whose type 476/// is Record. 477static Decl *getObjectForAnonymousRecordDecl(ASTContext &Context, 478 RecordDecl *Record) { 479 assert(Record->isAnonymousStructOrUnion() && 480 "Record must be an anonymous struct or union!"); 481 482 // FIXME: Once Decls are directly linked together, this will be an O(1) 483 // operation rather than a slow walk through DeclContext's vector (which 484 // itself will be eliminated). DeclGroups might make this even better. 485 DeclContext *Ctx = Record->getDeclContext(); 486 for (DeclContext::decl_iterator D = Ctx->decls_begin(), 487 DEnd = Ctx->decls_end(); 488 D != DEnd; ++D) { 489 if (*D == Record) { 490 // The object for the anonymous struct/union directly 491 // follows its type in the list of declarations. 492 ++D; 493 assert(D != DEnd && "Missing object for anonymous record"); 494 assert(!cast<NamedDecl>(*D)->getDeclName() && "Decl should be unnamed"); 495 return *D; 496 } 497 } 498 499 assert(false && "Missing object for anonymous record"); 500 return 0; 501} 502 503/// \brief Given a field that represents a member of an anonymous 504/// struct/union, build the path from that field's context to the 505/// actual member. 506/// 507/// Construct the sequence of field member references we'll have to 508/// perform to get to the field in the anonymous union/struct. The 509/// list of members is built from the field outward, so traverse it 510/// backwards to go from an object in the current context to the field 511/// we found. 512/// 513/// \returns The variable from which the field access should begin, 514/// for an anonymous struct/union that is not a member of another 515/// class. Otherwise, returns NULL. 516VarDecl *Sema::BuildAnonymousStructUnionMemberPath(FieldDecl *Field, 517 llvm::SmallVectorImpl<FieldDecl *> &Path) { 518 assert(Field->getDeclContext()->isRecord() && 519 cast<RecordDecl>(Field->getDeclContext())->isAnonymousStructOrUnion() 520 && "Field must be stored inside an anonymous struct or union"); 521 522 Path.push_back(Field); 523 VarDecl *BaseObject = 0; 524 DeclContext *Ctx = Field->getDeclContext(); 525 do { 526 RecordDecl *Record = cast<RecordDecl>(Ctx); 527 Decl *AnonObject = getObjectForAnonymousRecordDecl(Context, Record); 528 if (FieldDecl *AnonField = dyn_cast<FieldDecl>(AnonObject)) 529 Path.push_back(AnonField); 530 else { 531 BaseObject = cast<VarDecl>(AnonObject); 532 break; 533 } 534 Ctx = Ctx->getParent(); 535 } while (Ctx->isRecord() && 536 cast<RecordDecl>(Ctx)->isAnonymousStructOrUnion()); 537 538 return BaseObject; 539} 540 541Sema::OwningExprResult 542Sema::BuildAnonymousStructUnionMemberReference(SourceLocation Loc, 543 FieldDecl *Field, 544 Expr *BaseObjectExpr, 545 SourceLocation OpLoc) { 546 llvm::SmallVector<FieldDecl *, 4> AnonFields; 547 VarDecl *BaseObject = BuildAnonymousStructUnionMemberPath(Field, 548 AnonFields); 549 550 // Build the expression that refers to the base object, from 551 // which we will build a sequence of member references to each 552 // of the anonymous union objects and, eventually, the field we 553 // found via name lookup. 554 bool BaseObjectIsPointer = false; 555 Qualifiers BaseQuals; 556 if (BaseObject) { 557 // BaseObject is an anonymous struct/union variable (and is, 558 // therefore, not part of another non-anonymous record). 559 if (BaseObjectExpr) BaseObjectExpr->Destroy(Context); 560 MarkDeclarationReferenced(Loc, BaseObject); 561 BaseObjectExpr = new (Context) DeclRefExpr(BaseObject,BaseObject->getType(), 562 SourceLocation()); 563 BaseQuals 564 = Context.getCanonicalType(BaseObject->getType()).getQualifiers(); 565 } else if (BaseObjectExpr) { 566 // The caller provided the base object expression. Determine 567 // whether its a pointer and whether it adds any qualifiers to the 568 // anonymous struct/union fields we're looking into. 569 QualType ObjectType = BaseObjectExpr->getType(); 570 if (const PointerType *ObjectPtr = ObjectType->getAs<PointerType>()) { 571 BaseObjectIsPointer = true; 572 ObjectType = ObjectPtr->getPointeeType(); 573 } 574 BaseQuals 575 = Context.getCanonicalType(ObjectType).getQualifiers(); 576 } else { 577 // We've found a member of an anonymous struct/union that is 578 // inside a non-anonymous struct/union, so in a well-formed 579 // program our base object expression is "this". 580 if (CXXMethodDecl *MD = dyn_cast<CXXMethodDecl>(CurContext)) { 581 if (!MD->isStatic()) { 582 QualType AnonFieldType 583 = Context.getTagDeclType( 584 cast<RecordDecl>(AnonFields.back()->getDeclContext())); 585 QualType ThisType = Context.getTagDeclType(MD->getParent()); 586 if ((Context.getCanonicalType(AnonFieldType) 587 == Context.getCanonicalType(ThisType)) || 588 IsDerivedFrom(ThisType, AnonFieldType)) { 589 // Our base object expression is "this". 590 BaseObjectExpr = new (Context) CXXThisExpr(Loc, 591 MD->getThisType(Context), 592 /*isImplicit=*/true); 593 BaseObjectIsPointer = true; 594 } 595 } else { 596 return ExprError(Diag(Loc,diag::err_invalid_member_use_in_static_method) 597 << Field->getDeclName()); 598 } 599 BaseQuals = Qualifiers::fromCVRMask(MD->getTypeQualifiers()); 600 } 601 602 if (!BaseObjectExpr) 603 return ExprError(Diag(Loc, diag::err_invalid_non_static_member_use) 604 << Field->getDeclName()); 605 } 606 607 // Build the implicit member references to the field of the 608 // anonymous struct/union. 609 Expr *Result = BaseObjectExpr; 610 Qualifiers ResultQuals = BaseQuals; 611 for (llvm::SmallVector<FieldDecl *, 4>::reverse_iterator 612 FI = AnonFields.rbegin(), FIEnd = AnonFields.rend(); 613 FI != FIEnd; ++FI) { 614 QualType MemberType = (*FI)->getType(); 615 Qualifiers MemberTypeQuals = 616 Context.getCanonicalType(MemberType).getQualifiers(); 617 618 // CVR attributes from the base are picked up by members, 619 // except that 'mutable' members don't pick up 'const'. 620 if ((*FI)->isMutable()) 621 ResultQuals.removeConst(); 622 623 // GC attributes are never picked up by members. 624 ResultQuals.removeObjCGCAttr(); 625 626 // TR 18037 does not allow fields to be declared with address spaces. 627 assert(!MemberTypeQuals.hasAddressSpace()); 628 629 Qualifiers NewQuals = ResultQuals + MemberTypeQuals; 630 if (NewQuals != MemberTypeQuals) 631 MemberType = Context.getQualifiedType(MemberType, NewQuals); 632 633 MarkDeclarationReferenced(Loc, *FI); 634 PerformObjectMemberConversion(Result, *FI); 635 // FIXME: Might this end up being a qualified name? 636 Result = new (Context) MemberExpr(Result, BaseObjectIsPointer, *FI, 637 OpLoc, MemberType); 638 BaseObjectIsPointer = false; 639 ResultQuals = NewQuals; 640 } 641 642 return Owned(Result); 643} 644 645/// Decomposes the given name into a DeclarationName, its location, and 646/// possibly a list of template arguments. 647/// 648/// If this produces template arguments, it is permitted to call 649/// DecomposeTemplateName. 650/// 651/// This actually loses a lot of source location information for 652/// non-standard name kinds; we should consider preserving that in 653/// some way. 654static void DecomposeUnqualifiedId(Sema &SemaRef, 655 const UnqualifiedId &Id, 656 TemplateArgumentListInfo &Buffer, 657 DeclarationName &Name, 658 SourceLocation &NameLoc, 659 const TemplateArgumentListInfo *&TemplateArgs) { 660 if (Id.getKind() == UnqualifiedId::IK_TemplateId) { 661 Buffer.setLAngleLoc(Id.TemplateId->LAngleLoc); 662 Buffer.setRAngleLoc(Id.TemplateId->RAngleLoc); 663 664 ASTTemplateArgsPtr TemplateArgsPtr(SemaRef, 665 Id.TemplateId->getTemplateArgs(), 666 Id.TemplateId->NumArgs); 667 SemaRef.translateTemplateArguments(TemplateArgsPtr, Buffer); 668 TemplateArgsPtr.release(); 669 670 TemplateName TName = 671 Sema::TemplateTy::make(Id.TemplateId->Template).getAsVal<TemplateName>(); 672 673 Name = SemaRef.Context.getNameForTemplate(TName); 674 NameLoc = Id.TemplateId->TemplateNameLoc; 675 TemplateArgs = &Buffer; 676 } else { 677 Name = SemaRef.GetNameFromUnqualifiedId(Id); 678 NameLoc = Id.StartLocation; 679 TemplateArgs = 0; 680 } 681} 682 683/// Decompose the given template name into a list of lookup results. 684/// 685/// The unqualified ID must name a non-dependent template, which can 686/// be more easily tested by checking whether DecomposeUnqualifiedId 687/// found template arguments. 688static void DecomposeTemplateName(LookupResult &R, const UnqualifiedId &Id) { 689 assert(Id.getKind() == UnqualifiedId::IK_TemplateId); 690 TemplateName TName = 691 Sema::TemplateTy::make(Id.TemplateId->Template).getAsVal<TemplateName>(); 692 693 if (TemplateDecl *TD = TName.getAsTemplateDecl()) 694 R.addDecl(TD); 695 else if (OverloadedTemplateStorage *OT = TName.getAsOverloadedTemplate()) 696 for (OverloadedTemplateStorage::iterator I = OT->begin(), E = OT->end(); 697 I != E; ++I) 698 R.addDecl(*I); 699 700 R.resolveKind(); 701} 702 703/// Determines whether the given record is "fully-formed" at the given 704/// location, i.e. whether a qualified lookup into it is assured of 705/// getting consistent results already. 706static bool IsFullyFormedScope(Sema &SemaRef, CXXRecordDecl *Record) { 707 if (!Record->hasDefinition()) 708 return false; 709 710 for (CXXRecordDecl::base_class_iterator I = Record->bases_begin(), 711 E = Record->bases_end(); I != E; ++I) { 712 CanQualType BaseT = SemaRef.Context.getCanonicalType((*I).getType()); 713 CanQual<RecordType> BaseRT = BaseT->getAs<RecordType>(); 714 if (!BaseRT) return false; 715 716 CXXRecordDecl *BaseRecord = cast<CXXRecordDecl>(BaseRT->getDecl()); 717 if (!BaseRecord->hasDefinition() || 718 !IsFullyFormedScope(SemaRef, BaseRecord)) 719 return false; 720 } 721 722 return true; 723} 724 725/// Determines whether we can lookup this id-expression now or whether 726/// we have to wait until template instantiation is complete. 727static bool IsDependentIdExpression(Sema &SemaRef, const CXXScopeSpec &SS) { 728 DeclContext *DC = SemaRef.computeDeclContext(SS, false); 729 730 // If the qualifier scope isn't computable, it's definitely dependent. 731 if (!DC) return true; 732 733 // If the qualifier scope doesn't name a record, we can always look into it. 734 if (!isa<CXXRecordDecl>(DC)) return false; 735 736 // We can't look into record types unless they're fully-formed. 737 if (!IsFullyFormedScope(SemaRef, cast<CXXRecordDecl>(DC))) return true; 738 739 return false; 740} 741 742/// Determines if the given class is provably not derived from all of 743/// the prospective base classes. 744static bool IsProvablyNotDerivedFrom(Sema &SemaRef, 745 CXXRecordDecl *Record, 746 const llvm::SmallPtrSet<CXXRecordDecl*, 4> &Bases) { 747 if (Bases.count(Record->getCanonicalDecl())) 748 return false; 749 750 RecordDecl *RD = Record->getDefinition(); 751 if (!RD) return false; 752 Record = cast<CXXRecordDecl>(RD); 753 754 for (CXXRecordDecl::base_class_iterator I = Record->bases_begin(), 755 E = Record->bases_end(); I != E; ++I) { 756 CanQualType BaseT = SemaRef.Context.getCanonicalType((*I).getType()); 757 CanQual<RecordType> BaseRT = BaseT->getAs<RecordType>(); 758 if (!BaseRT) return false; 759 760 CXXRecordDecl *BaseRecord = cast<CXXRecordDecl>(BaseRT->getDecl()); 761 if (!IsProvablyNotDerivedFrom(SemaRef, BaseRecord, Bases)) 762 return false; 763 } 764 765 return true; 766} 767 768/// Determines if this is an instance member of a class. 769static bool IsInstanceMember(NamedDecl *D) { 770 assert(D->isCXXClassMember() && 771 "checking whether non-member is instance member"); 772 773 if (isa<FieldDecl>(D)) return true; 774 775 if (isa<CXXMethodDecl>(D)) 776 return !cast<CXXMethodDecl>(D)->isStatic(); 777 778 if (isa<FunctionTemplateDecl>(D)) { 779 D = cast<FunctionTemplateDecl>(D)->getTemplatedDecl(); 780 return !cast<CXXMethodDecl>(D)->isStatic(); 781 } 782 783 return false; 784} 785 786enum IMAKind { 787 /// The reference is definitely not an instance member access. 788 IMA_Static, 789 790 /// The reference may be an implicit instance member access. 791 IMA_Mixed, 792 793 /// The reference may be to an instance member, but it is invalid if 794 /// so, because the context is not an instance method. 795 IMA_Mixed_StaticContext, 796 797 /// The reference may be to an instance member, but it is invalid if 798 /// so, because the context is from an unrelated class. 799 IMA_Mixed_Unrelated, 800 801 /// The reference is definitely an implicit instance member access. 802 IMA_Instance, 803 804 /// The reference may be to an unresolved using declaration. 805 IMA_Unresolved, 806 807 /// The reference may be to an unresolved using declaration and the 808 /// context is not an instance method. 809 IMA_Unresolved_StaticContext, 810 811 /// The reference is to a member of an anonymous structure in a 812 /// non-class context. 813 IMA_AnonymousMember, 814 815 /// All possible referrents are instance members and the current 816 /// context is not an instance method. 817 IMA_Error_StaticContext, 818 819 /// All possible referrents are instance members of an unrelated 820 /// class. 821 IMA_Error_Unrelated 822}; 823 824/// The given lookup names class member(s) and is not being used for 825/// an address-of-member expression. Classify the type of access 826/// according to whether it's possible that this reference names an 827/// instance member. This is best-effort; it is okay to 828/// conservatively answer "yes", in which case some errors will simply 829/// not be caught until template-instantiation. 830static IMAKind ClassifyImplicitMemberAccess(Sema &SemaRef, 831 const LookupResult &R) { 832 assert(!R.empty() && (*R.begin())->isCXXClassMember()); 833 834 bool isStaticContext = 835 (!isa<CXXMethodDecl>(SemaRef.CurContext) || 836 cast<CXXMethodDecl>(SemaRef.CurContext)->isStatic()); 837 838 if (R.isUnresolvableResult()) 839 return isStaticContext ? IMA_Unresolved_StaticContext : IMA_Unresolved; 840 841 // Collect all the declaring classes of instance members we find. 842 bool hasNonInstance = false; 843 llvm::SmallPtrSet<CXXRecordDecl*, 4> Classes; 844 for (LookupResult::iterator I = R.begin(), E = R.end(); I != E; ++I) { 845 NamedDecl *D = (*I)->getUnderlyingDecl(); 846 if (IsInstanceMember(D)) { 847 CXXRecordDecl *R = cast<CXXRecordDecl>(D->getDeclContext()); 848 849 // If this is a member of an anonymous record, move out to the 850 // innermost non-anonymous struct or union. If there isn't one, 851 // that's a special case. 852 while (R->isAnonymousStructOrUnion()) { 853 R = dyn_cast<CXXRecordDecl>(R->getParent()); 854 if (!R) return IMA_AnonymousMember; 855 } 856 Classes.insert(R->getCanonicalDecl()); 857 } 858 else 859 hasNonInstance = true; 860 } 861 862 // If we didn't find any instance members, it can't be an implicit 863 // member reference. 864 if (Classes.empty()) 865 return IMA_Static; 866 867 // If the current context is not an instance method, it can't be 868 // an implicit member reference. 869 if (isStaticContext) 870 return (hasNonInstance ? IMA_Mixed_StaticContext : IMA_Error_StaticContext); 871 872 // If we can prove that the current context is unrelated to all the 873 // declaring classes, it can't be an implicit member reference (in 874 // which case it's an error if any of those members are selected). 875 if (IsProvablyNotDerivedFrom(SemaRef, 876 cast<CXXMethodDecl>(SemaRef.CurContext)->getParent(), 877 Classes)) 878 return (hasNonInstance ? IMA_Mixed_Unrelated : IMA_Error_Unrelated); 879 880 return (hasNonInstance ? IMA_Mixed : IMA_Instance); 881} 882 883/// Diagnose a reference to a field with no object available. 884static void DiagnoseInstanceReference(Sema &SemaRef, 885 const CXXScopeSpec &SS, 886 const LookupResult &R) { 887 SourceLocation Loc = R.getNameLoc(); 888 SourceRange Range(Loc); 889 if (SS.isSet()) Range.setBegin(SS.getRange().getBegin()); 890 891 if (R.getAsSingle<FieldDecl>()) { 892 if (CXXMethodDecl *MD = dyn_cast<CXXMethodDecl>(SemaRef.CurContext)) { 893 if (MD->isStatic()) { 894 // "invalid use of member 'x' in static member function" 895 SemaRef.Diag(Loc, diag::err_invalid_member_use_in_static_method) 896 << Range << R.getLookupName(); 897 return; 898 } 899 } 900 901 SemaRef.Diag(Loc, diag::err_invalid_non_static_member_use) 902 << R.getLookupName() << Range; 903 return; 904 } 905 906 SemaRef.Diag(Loc, diag::err_member_call_without_object) << Range; 907} 908 909/// Diagnose an empty lookup. 910/// 911/// \return false if new lookup candidates were found 912bool Sema::DiagnoseEmptyLookup(Scope *S, const CXXScopeSpec &SS, 913 LookupResult &R) { 914 DeclarationName Name = R.getLookupName(); 915 916 unsigned diagnostic = diag::err_undeclared_var_use; 917 unsigned diagnostic_suggest = diag::err_undeclared_var_use_suggest; 918 if (Name.getNameKind() == DeclarationName::CXXOperatorName || 919 Name.getNameKind() == DeclarationName::CXXLiteralOperatorName || 920 Name.getNameKind() == DeclarationName::CXXConversionFunctionName) { 921 diagnostic = diag::err_undeclared_use; 922 diagnostic_suggest = diag::err_undeclared_use_suggest; 923 } 924 925 // If the original lookup was an unqualified lookup, fake an 926 // unqualified lookup. This is useful when (for example) the 927 // original lookup would not have found something because it was a 928 // dependent name. 929 for (DeclContext *DC = SS.isEmpty()? CurContext : 0; 930 DC; DC = DC->getParent()) { 931 if (isa<CXXRecordDecl>(DC)) { 932 LookupQualifiedName(R, DC); 933 934 if (!R.empty()) { 935 // Don't give errors about ambiguities in this lookup. 936 R.suppressDiagnostics(); 937 938 CXXMethodDecl *CurMethod = dyn_cast<CXXMethodDecl>(CurContext); 939 bool isInstance = CurMethod && 940 CurMethod->isInstance() && 941 DC == CurMethod->getParent(); 942 943 // Give a code modification hint to insert 'this->'. 944 // TODO: fixit for inserting 'Base<T>::' in the other cases. 945 // Actually quite difficult! 946 if (isInstance) 947 Diag(R.getNameLoc(), diagnostic) << Name 948 << CodeModificationHint::CreateInsertion(R.getNameLoc(), 949 "this->"); 950 else 951 Diag(R.getNameLoc(), diagnostic) << Name; 952 953 // Do we really want to note all of these? 954 for (LookupResult::iterator I = R.begin(), E = R.end(); I != E; ++I) 955 Diag((*I)->getLocation(), diag::note_dependent_var_use); 956 957 // Tell the callee to try to recover. 958 return false; 959 } 960 } 961 } 962 963 // We didn't find anything, so try to correct for a typo. 964 if (S && CorrectTypo(R, S, &SS)) { 965 if (isa<ValueDecl>(*R.begin()) || isa<FunctionTemplateDecl>(*R.begin())) { 966 if (SS.isEmpty()) 967 Diag(R.getNameLoc(), diagnostic_suggest) << Name << R.getLookupName() 968 << CodeModificationHint::CreateReplacement(R.getNameLoc(), 969 R.getLookupName().getAsString()); 970 else 971 Diag(R.getNameLoc(), diag::err_no_member_suggest) 972 << Name << computeDeclContext(SS, false) << R.getLookupName() 973 << SS.getRange() 974 << CodeModificationHint::CreateReplacement(R.getNameLoc(), 975 R.getLookupName().getAsString()); 976 if (NamedDecl *ND = R.getAsSingle<NamedDecl>()) 977 Diag(ND->getLocation(), diag::note_previous_decl) 978 << ND->getDeclName(); 979 980 // Tell the callee to try to recover. 981 return false; 982 } 983 984 if (isa<TypeDecl>(*R.begin()) || isa<ObjCInterfaceDecl>(*R.begin())) { 985 // FIXME: If we ended up with a typo for a type name or 986 // Objective-C class name, we're in trouble because the parser 987 // is in the wrong place to recover. Suggest the typo 988 // correction, but don't make it a fix-it since we're not going 989 // to recover well anyway. 990 if (SS.isEmpty()) 991 Diag(R.getNameLoc(), diagnostic_suggest) << Name << R.getLookupName(); 992 else 993 Diag(R.getNameLoc(), diag::err_no_member_suggest) 994 << Name << computeDeclContext(SS, false) << R.getLookupName() 995 << SS.getRange(); 996 997 // Don't try to recover; it won't work. 998 return true; 999 } 1000 1001 R.clear(); 1002 } 1003 1004 // Emit a special diagnostic for failed member lookups. 1005 // FIXME: computing the declaration context might fail here (?) 1006 if (!SS.isEmpty()) { 1007 Diag(R.getNameLoc(), diag::err_no_member) 1008 << Name << computeDeclContext(SS, false) 1009 << SS.getRange(); 1010 return true; 1011 } 1012 1013 // Give up, we can't recover. 1014 Diag(R.getNameLoc(), diagnostic) << Name; 1015 return true; 1016} 1017 1018Sema::OwningExprResult Sema::ActOnIdExpression(Scope *S, 1019 const CXXScopeSpec &SS, 1020 UnqualifiedId &Id, 1021 bool HasTrailingLParen, 1022 bool isAddressOfOperand) { 1023 assert(!(isAddressOfOperand && HasTrailingLParen) && 1024 "cannot be direct & operand and have a trailing lparen"); 1025 1026 if (SS.isInvalid()) 1027 return ExprError(); 1028 1029 TemplateArgumentListInfo TemplateArgsBuffer; 1030 1031 // Decompose the UnqualifiedId into the following data. 1032 DeclarationName Name; 1033 SourceLocation NameLoc; 1034 const TemplateArgumentListInfo *TemplateArgs; 1035 DecomposeUnqualifiedId(*this, Id, TemplateArgsBuffer, 1036 Name, NameLoc, TemplateArgs); 1037 1038 IdentifierInfo *II = Name.getAsIdentifierInfo(); 1039 1040 // C++ [temp.dep.expr]p3: 1041 // An id-expression is type-dependent if it contains: 1042 // -- an identifier that was declared with a dependent type, 1043 // (note: handled after lookup) 1044 // -- a template-id that is dependent, 1045 // (note: handled in BuildTemplateIdExpr) 1046 // -- a conversion-function-id that specifies a dependent type, 1047 // -- a nested-name-specifier that contains a class-name that 1048 // names a dependent type. 1049 // Determine whether this is a member of an unknown specialization; 1050 // we need to handle these differently. 1051 if ((Name.getNameKind() == DeclarationName::CXXConversionFunctionName && 1052 Name.getCXXNameType()->isDependentType()) || 1053 (SS.isSet() && IsDependentIdExpression(*this, SS))) { 1054 return ActOnDependentIdExpression(SS, Name, NameLoc, 1055 isAddressOfOperand, 1056 TemplateArgs); 1057 } 1058 1059 // Perform the required lookup. 1060 LookupResult R(*this, Name, NameLoc, LookupOrdinaryName); 1061 if (TemplateArgs) { 1062 // Just re-use the lookup done by isTemplateName. 1063 DecomposeTemplateName(R, Id); 1064 } else { 1065 bool IvarLookupFollowUp = (!SS.isSet() && II && getCurMethodDecl()); 1066 LookupParsedName(R, S, &SS, !IvarLookupFollowUp); 1067 1068 // If this reference is in an Objective-C method, then we need to do 1069 // some special Objective-C lookup, too. 1070 if (IvarLookupFollowUp) { 1071 OwningExprResult E(LookupInObjCMethod(R, S, II, true)); 1072 if (E.isInvalid()) 1073 return ExprError(); 1074 1075 Expr *Ex = E.takeAs<Expr>(); 1076 if (Ex) return Owned(Ex); 1077 } 1078 } 1079 1080 if (R.isAmbiguous()) 1081 return ExprError(); 1082 1083 // Determine whether this name might be a candidate for 1084 // argument-dependent lookup. 1085 bool ADL = UseArgumentDependentLookup(SS, R, HasTrailingLParen); 1086 1087 if (R.empty() && !ADL) { 1088 // Otherwise, this could be an implicitly declared function reference (legal 1089 // in C90, extension in C99, forbidden in C++). 1090 if (HasTrailingLParen && II && !getLangOptions().CPlusPlus) { 1091 NamedDecl *D = ImplicitlyDefineFunction(NameLoc, *II, S); 1092 if (D) R.addDecl(D); 1093 } 1094 1095 // If this name wasn't predeclared and if this is not a function 1096 // call, diagnose the problem. 1097 if (R.empty()) { 1098 if (DiagnoseEmptyLookup(S, SS, R)) 1099 return ExprError(); 1100 1101 assert(!R.empty() && 1102 "DiagnoseEmptyLookup returned false but added no results"); 1103 1104 // If we found an Objective-C instance variable, let 1105 // LookupInObjCMethod build the appropriate expression to 1106 // reference the ivar. 1107 if (ObjCIvarDecl *Ivar = R.getAsSingle<ObjCIvarDecl>()) { 1108 R.clear(); 1109 OwningExprResult E(LookupInObjCMethod(R, S, Ivar->getIdentifier())); 1110 assert(E.isInvalid() || E.get()); 1111 return move(E); 1112 } 1113 } 1114 } 1115 1116 // This is guaranteed from this point on. 1117 assert(!R.empty() || ADL); 1118 1119 if (VarDecl *Var = R.getAsSingle<VarDecl>()) { 1120 // Warn about constructs like: 1121 // if (void *X = foo()) { ... } else { X }. 1122 // In the else block, the pointer is always false. 1123 1124 if (Var->isDeclaredInCondition() && Var->getType()->isScalarType()) { 1125 Scope *CheckS = S; 1126 while (CheckS && CheckS->getControlParent()) { 1127 if (CheckS->isWithinElse() && 1128 CheckS->getControlParent()->isDeclScope(DeclPtrTy::make(Var))) { 1129 ExprError(Diag(NameLoc, diag::warn_value_always_zero) 1130 << Var->getDeclName() 1131 << (Var->getType()->isPointerType()? 2 : 1132 Var->getType()->isBooleanType()? 1 : 0)); 1133 break; 1134 } 1135 1136 // Move to the parent of this scope. 1137 CheckS = CheckS->getParent(); 1138 } 1139 } 1140 } else if (FunctionDecl *Func = R.getAsSingle<FunctionDecl>()) { 1141 if (!getLangOptions().CPlusPlus && !Func->hasPrototype()) { 1142 // C99 DR 316 says that, if a function type comes from a 1143 // function definition (without a prototype), that type is only 1144 // used for checking compatibility. Therefore, when referencing 1145 // the function, we pretend that we don't have the full function 1146 // type. 1147 if (DiagnoseUseOfDecl(Func, NameLoc)) 1148 return ExprError(); 1149 1150 QualType T = Func->getType(); 1151 QualType NoProtoType = T; 1152 if (const FunctionProtoType *Proto = T->getAs<FunctionProtoType>()) 1153 NoProtoType = Context.getFunctionNoProtoType(Proto->getResultType()); 1154 return BuildDeclRefExpr(Func, NoProtoType, NameLoc, &SS); 1155 } 1156 } 1157 1158 // Check whether this might be a C++ implicit instance member access. 1159 // C++ [expr.prim.general]p6: 1160 // Within the definition of a non-static member function, an 1161 // identifier that names a non-static member is transformed to a 1162 // class member access expression. 1163 // But note that &SomeClass::foo is grammatically distinct, even 1164 // though we don't parse it that way. 1165 if (!R.empty() && (*R.begin())->isCXXClassMember()) { 1166 bool isAbstractMemberPointer = (isAddressOfOperand && !SS.isEmpty()); 1167 if (!isAbstractMemberPointer) 1168 return BuildPossibleImplicitMemberExpr(SS, R, TemplateArgs); 1169 } 1170 1171 if (TemplateArgs) 1172 return BuildTemplateIdExpr(SS, R, ADL, *TemplateArgs); 1173 1174 return BuildDeclarationNameExpr(SS, R, ADL); 1175} 1176 1177/// Builds an expression which might be an implicit member expression. 1178Sema::OwningExprResult 1179Sema::BuildPossibleImplicitMemberExpr(const CXXScopeSpec &SS, 1180 LookupResult &R, 1181 const TemplateArgumentListInfo *TemplateArgs) { 1182 switch (ClassifyImplicitMemberAccess(*this, R)) { 1183 case IMA_Instance: 1184 return BuildImplicitMemberExpr(SS, R, TemplateArgs, true); 1185 1186 case IMA_AnonymousMember: 1187 assert(R.isSingleResult()); 1188 return BuildAnonymousStructUnionMemberReference(R.getNameLoc(), 1189 R.getAsSingle<FieldDecl>()); 1190 1191 case IMA_Mixed: 1192 case IMA_Mixed_Unrelated: 1193 case IMA_Unresolved: 1194 return BuildImplicitMemberExpr(SS, R, TemplateArgs, false); 1195 1196 case IMA_Static: 1197 case IMA_Mixed_StaticContext: 1198 case IMA_Unresolved_StaticContext: 1199 if (TemplateArgs) 1200 return BuildTemplateIdExpr(SS, R, false, *TemplateArgs); 1201 return BuildDeclarationNameExpr(SS, R, false); 1202 1203 case IMA_Error_StaticContext: 1204 case IMA_Error_Unrelated: 1205 DiagnoseInstanceReference(*this, SS, R); 1206 return ExprError(); 1207 } 1208 1209 llvm_unreachable("unexpected instance member access kind"); 1210 return ExprError(); 1211} 1212 1213/// BuildQualifiedDeclarationNameExpr - Build a C++ qualified 1214/// declaration name, generally during template instantiation. 1215/// There's a large number of things which don't need to be done along 1216/// this path. 1217Sema::OwningExprResult 1218Sema::BuildQualifiedDeclarationNameExpr(const CXXScopeSpec &SS, 1219 DeclarationName Name, 1220 SourceLocation NameLoc) { 1221 DeclContext *DC; 1222 if (!(DC = computeDeclContext(SS, false)) || 1223 DC->isDependentContext() || 1224 RequireCompleteDeclContext(SS)) 1225 return BuildDependentDeclRefExpr(SS, Name, NameLoc, 0); 1226 1227 LookupResult R(*this, Name, NameLoc, LookupOrdinaryName); 1228 LookupQualifiedName(R, DC); 1229 1230 if (R.isAmbiguous()) 1231 return ExprError(); 1232 1233 if (R.empty()) { 1234 Diag(NameLoc, diag::err_no_member) << Name << DC << SS.getRange(); 1235 return ExprError(); 1236 } 1237 1238 return BuildDeclarationNameExpr(SS, R, /*ADL*/ false); 1239} 1240 1241/// LookupInObjCMethod - The parser has read a name in, and Sema has 1242/// detected that we're currently inside an ObjC method. Perform some 1243/// additional lookup. 1244/// 1245/// Ideally, most of this would be done by lookup, but there's 1246/// actually quite a lot of extra work involved. 1247/// 1248/// Returns a null sentinel to indicate trivial success. 1249Sema::OwningExprResult 1250Sema::LookupInObjCMethod(LookupResult &Lookup, Scope *S, 1251 IdentifierInfo *II, 1252 bool AllowBuiltinCreation) { 1253 SourceLocation Loc = Lookup.getNameLoc(); 1254 1255 // There are two cases to handle here. 1) scoped lookup could have failed, 1256 // in which case we should look for an ivar. 2) scoped lookup could have 1257 // found a decl, but that decl is outside the current instance method (i.e. 1258 // a global variable). In these two cases, we do a lookup for an ivar with 1259 // this name, if the lookup sucedes, we replace it our current decl. 1260 1261 // If we're in a class method, we don't normally want to look for 1262 // ivars. But if we don't find anything else, and there's an 1263 // ivar, that's an error. 1264 bool IsClassMethod = getCurMethodDecl()->isClassMethod(); 1265 1266 bool LookForIvars; 1267 if (Lookup.empty()) 1268 LookForIvars = true; 1269 else if (IsClassMethod) 1270 LookForIvars = false; 1271 else 1272 LookForIvars = (Lookup.isSingleResult() && 1273 Lookup.getFoundDecl()->isDefinedOutsideFunctionOrMethod()); 1274 ObjCInterfaceDecl *IFace = 0; 1275 if (LookForIvars) { 1276 IFace = getCurMethodDecl()->getClassInterface(); 1277 ObjCInterfaceDecl *ClassDeclared; 1278 if (ObjCIvarDecl *IV = IFace->lookupInstanceVariable(II, ClassDeclared)) { 1279 // Diagnose using an ivar in a class method. 1280 if (IsClassMethod) 1281 return ExprError(Diag(Loc, diag::error_ivar_use_in_class_method) 1282 << IV->getDeclName()); 1283 1284 // If we're referencing an invalid decl, just return this as a silent 1285 // error node. The error diagnostic was already emitted on the decl. 1286 if (IV->isInvalidDecl()) 1287 return ExprError(); 1288 1289 // Check if referencing a field with __attribute__((deprecated)). 1290 if (DiagnoseUseOfDecl(IV, Loc)) 1291 return ExprError(); 1292 1293 // Diagnose the use of an ivar outside of the declaring class. 1294 if (IV->getAccessControl() == ObjCIvarDecl::Private && 1295 ClassDeclared != IFace) 1296 Diag(Loc, diag::error_private_ivar_access) << IV->getDeclName(); 1297 1298 // FIXME: This should use a new expr for a direct reference, don't 1299 // turn this into Self->ivar, just return a BareIVarExpr or something. 1300 IdentifierInfo &II = Context.Idents.get("self"); 1301 UnqualifiedId SelfName; 1302 SelfName.setIdentifier(&II, SourceLocation()); 1303 CXXScopeSpec SelfScopeSpec; 1304 OwningExprResult SelfExpr = ActOnIdExpression(S, SelfScopeSpec, 1305 SelfName, false, false); 1306 MarkDeclarationReferenced(Loc, IV); 1307 return Owned(new (Context) 1308 ObjCIvarRefExpr(IV, IV->getType(), Loc, 1309 SelfExpr.takeAs<Expr>(), true, true)); 1310 } 1311 } else if (getCurMethodDecl()->isInstanceMethod()) { 1312 // We should warn if a local variable hides an ivar. 1313 ObjCInterfaceDecl *IFace = getCurMethodDecl()->getClassInterface(); 1314 ObjCInterfaceDecl *ClassDeclared; 1315 if (ObjCIvarDecl *IV = IFace->lookupInstanceVariable(II, ClassDeclared)) { 1316 if (IV->getAccessControl() != ObjCIvarDecl::Private || 1317 IFace == ClassDeclared) 1318 Diag(Loc, diag::warn_ivar_use_hidden) << IV->getDeclName(); 1319 } 1320 } 1321 1322 // Needed to implement property "super.method" notation. 1323 if (Lookup.empty() && II->isStr("super")) { 1324 QualType T; 1325 1326 if (getCurMethodDecl()->isInstanceMethod()) 1327 T = Context.getObjCObjectPointerType(Context.getObjCInterfaceType( 1328 getCurMethodDecl()->getClassInterface())); 1329 else 1330 T = Context.getObjCClassType(); 1331 return Owned(new (Context) ObjCSuperExpr(Loc, T)); 1332 } 1333 if (Lookup.empty() && II && AllowBuiltinCreation) { 1334 // FIXME. Consolidate this with similar code in LookupName. 1335 if (unsigned BuiltinID = II->getBuiltinID()) { 1336 if (!(getLangOptions().CPlusPlus && 1337 Context.BuiltinInfo.isPredefinedLibFunction(BuiltinID))) { 1338 NamedDecl *D = LazilyCreateBuiltin((IdentifierInfo *)II, BuiltinID, 1339 S, Lookup.isForRedeclaration(), 1340 Lookup.getNameLoc()); 1341 if (D) Lookup.addDecl(D); 1342 } 1343 } 1344 } 1345 if (LangOpts.ObjCNonFragileABI2 && LookForIvars && Lookup.empty()) { 1346 ObjCIvarDecl *Ivar = SynthesizeNewPropertyIvar(IFace, II); 1347 if (Ivar) 1348 return LookupInObjCMethod(Lookup, S, II, AllowBuiltinCreation); 1349 } 1350 // Sentinel value saying that we didn't do anything special. 1351 return Owned((Expr*) 0); 1352} 1353 1354/// \brief Cast member's object to its own class if necessary. 1355bool 1356Sema::PerformObjectMemberConversion(Expr *&From, NamedDecl *Member) { 1357 if (FieldDecl *FD = dyn_cast<FieldDecl>(Member)) 1358 if (CXXRecordDecl *RD = 1359 dyn_cast<CXXRecordDecl>(FD->getDeclContext())) { 1360 QualType DestType = 1361 Context.getCanonicalType(Context.getTypeDeclType(RD)); 1362 if (DestType->isDependentType() || From->getType()->isDependentType()) 1363 return false; 1364 QualType FromRecordType = From->getType(); 1365 QualType DestRecordType = DestType; 1366 if (FromRecordType->getAs<PointerType>()) { 1367 DestType = Context.getPointerType(DestType); 1368 FromRecordType = FromRecordType->getPointeeType(); 1369 } 1370 if (!Context.hasSameUnqualifiedType(FromRecordType, DestRecordType) && 1371 CheckDerivedToBaseConversion(FromRecordType, 1372 DestRecordType, 1373 From->getSourceRange().getBegin(), 1374 From->getSourceRange())) 1375 return true; 1376 ImpCastExprToType(From, DestType, CastExpr::CK_DerivedToBase, 1377 /*isLvalue=*/true); 1378 } 1379 return false; 1380} 1381 1382/// \brief Build a MemberExpr AST node. 1383static MemberExpr *BuildMemberExpr(ASTContext &C, Expr *Base, bool isArrow, 1384 const CXXScopeSpec &SS, ValueDecl *Member, 1385 SourceLocation Loc, QualType Ty, 1386 const TemplateArgumentListInfo *TemplateArgs = 0) { 1387 NestedNameSpecifier *Qualifier = 0; 1388 SourceRange QualifierRange; 1389 if (SS.isSet()) { 1390 Qualifier = (NestedNameSpecifier *) SS.getScopeRep(); 1391 QualifierRange = SS.getRange(); 1392 } 1393 1394 return MemberExpr::Create(C, Base, isArrow, Qualifier, QualifierRange, 1395 Member, Loc, TemplateArgs, Ty); 1396} 1397 1398/// Builds an implicit member access expression. The current context 1399/// is known to be an instance method, and the given unqualified lookup 1400/// set is known to contain only instance members, at least one of which 1401/// is from an appropriate type. 1402Sema::OwningExprResult 1403Sema::BuildImplicitMemberExpr(const CXXScopeSpec &SS, 1404 LookupResult &R, 1405 const TemplateArgumentListInfo *TemplateArgs, 1406 bool IsKnownInstance) { 1407 assert(!R.empty() && !R.isAmbiguous()); 1408 1409 SourceLocation Loc = R.getNameLoc(); 1410 1411 // We may have found a field within an anonymous union or struct 1412 // (C++ [class.union]). 1413 // FIXME: This needs to happen post-isImplicitMemberReference? 1414 // FIXME: template-ids inside anonymous structs? 1415 if (FieldDecl *FD = R.getAsSingle<FieldDecl>()) 1416 if (cast<RecordDecl>(FD->getDeclContext())->isAnonymousStructOrUnion()) 1417 return BuildAnonymousStructUnionMemberReference(Loc, FD); 1418 1419 // If this is known to be an instance access, go ahead and build a 1420 // 'this' expression now. 1421 QualType ThisType = cast<CXXMethodDecl>(CurContext)->getThisType(Context); 1422 Expr *This = 0; // null signifies implicit access 1423 if (IsKnownInstance) { 1424 SourceLocation Loc = R.getNameLoc(); 1425 if (SS.getRange().isValid()) 1426 Loc = SS.getRange().getBegin(); 1427 This = new (Context) CXXThisExpr(Loc, ThisType, /*isImplicit=*/true); 1428 } 1429 1430 return BuildMemberReferenceExpr(ExprArg(*this, This), ThisType, 1431 /*OpLoc*/ SourceLocation(), 1432 /*IsArrow*/ true, 1433 SS, 1434 /*FirstQualifierInScope*/ 0, 1435 R, TemplateArgs); 1436} 1437 1438bool Sema::UseArgumentDependentLookup(const CXXScopeSpec &SS, 1439 const LookupResult &R, 1440 bool HasTrailingLParen) { 1441 // Only when used directly as the postfix-expression of a call. 1442 if (!HasTrailingLParen) 1443 return false; 1444 1445 // Never if a scope specifier was provided. 1446 if (SS.isSet()) 1447 return false; 1448 1449 // Only in C++ or ObjC++. 1450 if (!getLangOptions().CPlusPlus) 1451 return false; 1452 1453 // Turn off ADL when we find certain kinds of declarations during 1454 // normal lookup: 1455 for (LookupResult::iterator I = R.begin(), E = R.end(); I != E; ++I) { 1456 NamedDecl *D = *I; 1457 1458 // C++0x [basic.lookup.argdep]p3: 1459 // -- a declaration of a class member 1460 // Since using decls preserve this property, we check this on the 1461 // original decl. 1462 if (D->isCXXClassMember()) 1463 return false; 1464 1465 // C++0x [basic.lookup.argdep]p3: 1466 // -- a block-scope function declaration that is not a 1467 // using-declaration 1468 // NOTE: we also trigger this for function templates (in fact, we 1469 // don't check the decl type at all, since all other decl types 1470 // turn off ADL anyway). 1471 if (isa<UsingShadowDecl>(D)) 1472 D = cast<UsingShadowDecl>(D)->getTargetDecl(); 1473 else if (D->getDeclContext()->isFunctionOrMethod()) 1474 return false; 1475 1476 // C++0x [basic.lookup.argdep]p3: 1477 // -- a declaration that is neither a function or a function 1478 // template 1479 // And also for builtin functions. 1480 if (isa<FunctionDecl>(D)) { 1481 FunctionDecl *FDecl = cast<FunctionDecl>(D); 1482 1483 // But also builtin functions. 1484 if (FDecl->getBuiltinID() && FDecl->isImplicit()) 1485 return false; 1486 } else if (!isa<FunctionTemplateDecl>(D)) 1487 return false; 1488 } 1489 1490 return true; 1491} 1492 1493 1494/// Diagnoses obvious problems with the use of the given declaration 1495/// as an expression. This is only actually called for lookups that 1496/// were not overloaded, and it doesn't promise that the declaration 1497/// will in fact be used. 1498static bool CheckDeclInExpr(Sema &S, SourceLocation Loc, NamedDecl *D) { 1499 if (isa<TypedefDecl>(D)) { 1500 S.Diag(Loc, diag::err_unexpected_typedef) << D->getDeclName(); 1501 return true; 1502 } 1503 1504 if (isa<ObjCInterfaceDecl>(D)) { 1505 S.Diag(Loc, diag::err_unexpected_interface) << D->getDeclName(); 1506 return true; 1507 } 1508 1509 if (isa<NamespaceDecl>(D)) { 1510 S.Diag(Loc, diag::err_unexpected_namespace) << D->getDeclName(); 1511 return true; 1512 } 1513 1514 return false; 1515} 1516 1517Sema::OwningExprResult 1518Sema::BuildDeclarationNameExpr(const CXXScopeSpec &SS, 1519 LookupResult &R, 1520 bool NeedsADL) { 1521 // If this is a single, fully-resolved result and we don't need ADL, 1522 // just build an ordinary singleton decl ref. 1523 if (!NeedsADL && R.isSingleResult() && !R.getAsSingle<FunctionTemplateDecl>()) 1524 return BuildDeclarationNameExpr(SS, R.getNameLoc(), R.getFoundDecl()); 1525 1526 // We only need to check the declaration if there's exactly one 1527 // result, because in the overloaded case the results can only be 1528 // functions and function templates. 1529 if (R.isSingleResult() && 1530 CheckDeclInExpr(*this, R.getNameLoc(), R.getFoundDecl())) 1531 return ExprError(); 1532 1533 // Otherwise, just build an unresolved lookup expression. Suppress 1534 // any lookup-related diagnostics; we'll hash these out later, when 1535 // we've picked a target. 1536 R.suppressDiagnostics(); 1537 1538 bool Dependent 1539 = UnresolvedLookupExpr::ComputeDependence(R.begin(), R.end(), 0); 1540 UnresolvedLookupExpr *ULE 1541 = UnresolvedLookupExpr::Create(Context, Dependent, R.getNamingClass(), 1542 (NestedNameSpecifier*) SS.getScopeRep(), 1543 SS.getRange(), 1544 R.getLookupName(), R.getNameLoc(), 1545 NeedsADL, R.isOverloadedResult()); 1546 ULE->addDecls(R.begin(), R.end()); 1547 1548 return Owned(ULE); 1549} 1550 1551 1552/// \brief Complete semantic analysis for a reference to the given declaration. 1553Sema::OwningExprResult 1554Sema::BuildDeclarationNameExpr(const CXXScopeSpec &SS, 1555 SourceLocation Loc, NamedDecl *D) { 1556 assert(D && "Cannot refer to a NULL declaration"); 1557 assert(!isa<FunctionTemplateDecl>(D) && 1558 "Cannot refer unambiguously to a function template"); 1559 1560 if (CheckDeclInExpr(*this, Loc, D)) 1561 return ExprError(); 1562 1563 if (TemplateDecl *Template = dyn_cast<TemplateDecl>(D)) { 1564 // Specifically diagnose references to class templates that are missing 1565 // a template argument list. 1566 Diag(Loc, diag::err_template_decl_ref) 1567 << Template << SS.getRange(); 1568 Diag(Template->getLocation(), diag::note_template_decl_here); 1569 return ExprError(); 1570 } 1571 1572 // Make sure that we're referring to a value. 1573 ValueDecl *VD = dyn_cast<ValueDecl>(D); 1574 if (!VD) { 1575 Diag(Loc, diag::err_ref_non_value) 1576 << D << SS.getRange(); 1577 Diag(D->getLocation(), diag::note_declared_at); 1578 return ExprError(); 1579 } 1580 1581 // Check whether this declaration can be used. Note that we suppress 1582 // this check when we're going to perform argument-dependent lookup 1583 // on this function name, because this might not be the function 1584 // that overload resolution actually selects. 1585 if (DiagnoseUseOfDecl(VD, Loc)) 1586 return ExprError(); 1587 1588 // Only create DeclRefExpr's for valid Decl's. 1589 if (VD->isInvalidDecl()) 1590 return ExprError(); 1591 1592 // If the identifier reference is inside a block, and it refers to a value 1593 // that is outside the block, create a BlockDeclRefExpr instead of a 1594 // DeclRefExpr. This ensures the value is treated as a copy-in snapshot when 1595 // the block is formed. 1596 // 1597 // We do not do this for things like enum constants, global variables, etc, 1598 // as they do not get snapshotted. 1599 // 1600 if (CurBlock && ShouldSnapshotBlockValueReference(CurBlock, VD)) { 1601 if (VD->getType().getTypePtr()->isVariablyModifiedType()) { 1602 Diag(Loc, diag::err_ref_vm_type); 1603 Diag(D->getLocation(), diag::note_declared_at); 1604 return ExprError(); 1605 } 1606 1607 if (VD->getType()->isArrayType()) { 1608 Diag(Loc, diag::err_ref_array_type); 1609 Diag(D->getLocation(), diag::note_declared_at); 1610 return ExprError(); 1611 } 1612 1613 MarkDeclarationReferenced(Loc, VD); 1614 QualType ExprTy = VD->getType().getNonReferenceType(); 1615 // The BlocksAttr indicates the variable is bound by-reference. 1616 if (VD->getAttr<BlocksAttr>()) 1617 return Owned(new (Context) BlockDeclRefExpr(VD, ExprTy, Loc, true)); 1618 // This is to record that a 'const' was actually synthesize and added. 1619 bool constAdded = !ExprTy.isConstQualified(); 1620 // Variable will be bound by-copy, make it const within the closure. 1621 1622 ExprTy.addConst(); 1623 return Owned(new (Context) BlockDeclRefExpr(VD, ExprTy, Loc, false, 1624 constAdded)); 1625 } 1626 // If this reference is not in a block or if the referenced variable is 1627 // within the block, create a normal DeclRefExpr. 1628 1629 return BuildDeclRefExpr(VD, VD->getType().getNonReferenceType(), Loc, &SS); 1630} 1631 1632Sema::OwningExprResult Sema::ActOnPredefinedExpr(SourceLocation Loc, 1633 tok::TokenKind Kind) { 1634 PredefinedExpr::IdentType IT; 1635 1636 switch (Kind) { 1637 default: assert(0 && "Unknown simple primary expr!"); 1638 case tok::kw___func__: IT = PredefinedExpr::Func; break; // [C99 6.4.2.2] 1639 case tok::kw___FUNCTION__: IT = PredefinedExpr::Function; break; 1640 case tok::kw___PRETTY_FUNCTION__: IT = PredefinedExpr::PrettyFunction; break; 1641 } 1642 1643 // Pre-defined identifiers are of type char[x], where x is the length of the 1644 // string. 1645 1646 Decl *currentDecl = getCurFunctionOrMethodDecl(); 1647 if (!currentDecl) { 1648 Diag(Loc, diag::ext_predef_outside_function); 1649 currentDecl = Context.getTranslationUnitDecl(); 1650 } 1651 1652 QualType ResTy; 1653 if (cast<DeclContext>(currentDecl)->isDependentContext()) { 1654 ResTy = Context.DependentTy; 1655 } else { 1656 unsigned Length = PredefinedExpr::ComputeName(IT, currentDecl).length(); 1657 1658 llvm::APInt LengthI(32, Length + 1); 1659 ResTy = Context.CharTy.withConst(); 1660 ResTy = Context.getConstantArrayType(ResTy, LengthI, ArrayType::Normal, 0); 1661 } 1662 return Owned(new (Context) PredefinedExpr(Loc, ResTy, IT)); 1663} 1664 1665Sema::OwningExprResult Sema::ActOnCharacterConstant(const Token &Tok) { 1666 llvm::SmallString<16> CharBuffer; 1667 CharBuffer.resize(Tok.getLength()); 1668 const char *ThisTokBegin = &CharBuffer[0]; 1669 unsigned ActualLength = PP.getSpelling(Tok, ThisTokBegin); 1670 1671 CharLiteralParser Literal(ThisTokBegin, ThisTokBegin+ActualLength, 1672 Tok.getLocation(), PP); 1673 if (Literal.hadError()) 1674 return ExprError(); 1675 1676 QualType Ty; 1677 if (!getLangOptions().CPlusPlus) 1678 Ty = Context.IntTy; // 'x' and L'x' -> int in C. 1679 else if (Literal.isWide()) 1680 Ty = Context.WCharTy; // L'x' -> wchar_t in C++. 1681 else if (Literal.isMultiChar()) 1682 Ty = Context.IntTy; // 'wxyz' -> int in C++. 1683 else 1684 Ty = Context.CharTy; // 'x' -> char in C++ 1685 1686 return Owned(new (Context) CharacterLiteral(Literal.getValue(), 1687 Literal.isWide(), 1688 Ty, Tok.getLocation())); 1689} 1690 1691Action::OwningExprResult Sema::ActOnNumericConstant(const Token &Tok) { 1692 // Fast path for a single digit (which is quite common). A single digit 1693 // cannot have a trigraph, escaped newline, radix prefix, or type suffix. 1694 if (Tok.getLength() == 1) { 1695 const char Val = PP.getSpellingOfSingleCharacterNumericConstant(Tok); 1696 unsigned IntSize = Context.Target.getIntWidth(); 1697 return Owned(new (Context) IntegerLiteral(llvm::APInt(IntSize, Val-'0'), 1698 Context.IntTy, Tok.getLocation())); 1699 } 1700 1701 llvm::SmallString<512> IntegerBuffer; 1702 // Add padding so that NumericLiteralParser can overread by one character. 1703 IntegerBuffer.resize(Tok.getLength()+1); 1704 const char *ThisTokBegin = &IntegerBuffer[0]; 1705 1706 // Get the spelling of the token, which eliminates trigraphs, etc. 1707 unsigned ActualLength = PP.getSpelling(Tok, ThisTokBegin); 1708 1709 NumericLiteralParser Literal(ThisTokBegin, ThisTokBegin+ActualLength, 1710 Tok.getLocation(), PP); 1711 if (Literal.hadError) 1712 return ExprError(); 1713 1714 Expr *Res; 1715 1716 if (Literal.isFloatingLiteral()) { 1717 QualType Ty; 1718 if (Literal.isFloat) 1719 Ty = Context.FloatTy; 1720 else if (!Literal.isLong) 1721 Ty = Context.DoubleTy; 1722 else 1723 Ty = Context.LongDoubleTy; 1724 1725 const llvm::fltSemantics &Format = Context.getFloatTypeSemantics(Ty); 1726 1727 using llvm::APFloat; 1728 APFloat Val(Format); 1729 1730 APFloat::opStatus result = Literal.GetFloatValue(Val); 1731 1732 // Overflow is always an error, but underflow is only an error if 1733 // we underflowed to zero (APFloat reports denormals as underflow). 1734 if ((result & APFloat::opOverflow) || 1735 ((result & APFloat::opUnderflow) && Val.isZero())) { 1736 unsigned diagnostic; 1737 llvm::SmallVector<char, 20> buffer; 1738 if (result & APFloat::opOverflow) { 1739 diagnostic = diag::err_float_overflow; 1740 APFloat::getLargest(Format).toString(buffer); 1741 } else { 1742 diagnostic = diag::err_float_underflow; 1743 APFloat::getSmallest(Format).toString(buffer); 1744 } 1745 1746 Diag(Tok.getLocation(), diagnostic) 1747 << Ty 1748 << llvm::StringRef(buffer.data(), buffer.size()); 1749 } 1750 1751 bool isExact = (result == APFloat::opOK); 1752 Res = new (Context) FloatingLiteral(Val, isExact, Ty, Tok.getLocation()); 1753 1754 } else if (!Literal.isIntegerLiteral()) { 1755 return ExprError(); 1756 } else { 1757 QualType Ty; 1758 1759 // long long is a C99 feature. 1760 if (!getLangOptions().C99 && !getLangOptions().CPlusPlus0x && 1761 Literal.isLongLong) 1762 Diag(Tok.getLocation(), diag::ext_longlong); 1763 1764 // Get the value in the widest-possible width. 1765 llvm::APInt ResultVal(Context.Target.getIntMaxTWidth(), 0); 1766 1767 if (Literal.GetIntegerValue(ResultVal)) { 1768 // If this value didn't fit into uintmax_t, warn and force to ull. 1769 Diag(Tok.getLocation(), diag::warn_integer_too_large); 1770 Ty = Context.UnsignedLongLongTy; 1771 assert(Context.getTypeSize(Ty) == ResultVal.getBitWidth() && 1772 "long long is not intmax_t?"); 1773 } else { 1774 // If this value fits into a ULL, try to figure out what else it fits into 1775 // according to the rules of C99 6.4.4.1p5. 1776 1777 // Octal, Hexadecimal, and integers with a U suffix are allowed to 1778 // be an unsigned int. 1779 bool AllowUnsigned = Literal.isUnsigned || Literal.getRadix() != 10; 1780 1781 // Check from smallest to largest, picking the smallest type we can. 1782 unsigned Width = 0; 1783 if (!Literal.isLong && !Literal.isLongLong) { 1784 // Are int/unsigned possibilities? 1785 unsigned IntSize = Context.Target.getIntWidth(); 1786 1787 // Does it fit in a unsigned int? 1788 if (ResultVal.isIntN(IntSize)) { 1789 // Does it fit in a signed int? 1790 if (!Literal.isUnsigned && ResultVal[IntSize-1] == 0) 1791 Ty = Context.IntTy; 1792 else if (AllowUnsigned) 1793 Ty = Context.UnsignedIntTy; 1794 Width = IntSize; 1795 } 1796 } 1797 1798 // Are long/unsigned long possibilities? 1799 if (Ty.isNull() && !Literal.isLongLong) { 1800 unsigned LongSize = Context.Target.getLongWidth(); 1801 1802 // Does it fit in a unsigned long? 1803 if (ResultVal.isIntN(LongSize)) { 1804 // Does it fit in a signed long? 1805 if (!Literal.isUnsigned && ResultVal[LongSize-1] == 0) 1806 Ty = Context.LongTy; 1807 else if (AllowUnsigned) 1808 Ty = Context.UnsignedLongTy; 1809 Width = LongSize; 1810 } 1811 } 1812 1813 // Finally, check long long if needed. 1814 if (Ty.isNull()) { 1815 unsigned LongLongSize = Context.Target.getLongLongWidth(); 1816 1817 // Does it fit in a unsigned long long? 1818 if (ResultVal.isIntN(LongLongSize)) { 1819 // Does it fit in a signed long long? 1820 if (!Literal.isUnsigned && ResultVal[LongLongSize-1] == 0) 1821 Ty = Context.LongLongTy; 1822 else if (AllowUnsigned) 1823 Ty = Context.UnsignedLongLongTy; 1824 Width = LongLongSize; 1825 } 1826 } 1827 1828 // If we still couldn't decide a type, we probably have something that 1829 // does not fit in a signed long long, but has no U suffix. 1830 if (Ty.isNull()) { 1831 Diag(Tok.getLocation(), diag::warn_integer_too_large_for_signed); 1832 Ty = Context.UnsignedLongLongTy; 1833 Width = Context.Target.getLongLongWidth(); 1834 } 1835 1836 if (ResultVal.getBitWidth() != Width) 1837 ResultVal.trunc(Width); 1838 } 1839 Res = new (Context) IntegerLiteral(ResultVal, Ty, Tok.getLocation()); 1840 } 1841 1842 // If this is an imaginary literal, create the ImaginaryLiteral wrapper. 1843 if (Literal.isImaginary) 1844 Res = new (Context) ImaginaryLiteral(Res, 1845 Context.getComplexType(Res->getType())); 1846 1847 return Owned(Res); 1848} 1849 1850Action::OwningExprResult Sema::ActOnParenExpr(SourceLocation L, 1851 SourceLocation R, ExprArg Val) { 1852 Expr *E = Val.takeAs<Expr>(); 1853 assert((E != 0) && "ActOnParenExpr() missing expr"); 1854 return Owned(new (Context) ParenExpr(L, R, E)); 1855} 1856 1857/// The UsualUnaryConversions() function is *not* called by this routine. 1858/// See C99 6.3.2.1p[2-4] for more details. 1859bool Sema::CheckSizeOfAlignOfOperand(QualType exprType, 1860 SourceLocation OpLoc, 1861 const SourceRange &ExprRange, 1862 bool isSizeof) { 1863 if (exprType->isDependentType()) 1864 return false; 1865 1866 // C++ [expr.sizeof]p2: "When applied to a reference or a reference type, 1867 // the result is the size of the referenced type." 1868 // C++ [expr.alignof]p3: "When alignof is applied to a reference type, the 1869 // result shall be the alignment of the referenced type." 1870 if (const ReferenceType *Ref = exprType->getAs<ReferenceType>()) 1871 exprType = Ref->getPointeeType(); 1872 1873 // C99 6.5.3.4p1: 1874 if (exprType->isFunctionType()) { 1875 // alignof(function) is allowed as an extension. 1876 if (isSizeof) 1877 Diag(OpLoc, diag::ext_sizeof_function_type) << ExprRange; 1878 return false; 1879 } 1880 1881 // Allow sizeof(void)/alignof(void) as an extension. 1882 if (exprType->isVoidType()) { 1883 Diag(OpLoc, diag::ext_sizeof_void_type) 1884 << (isSizeof ? "sizeof" : "__alignof") << ExprRange; 1885 return false; 1886 } 1887 1888 if (RequireCompleteType(OpLoc, exprType, 1889 PDiag(diag::err_sizeof_alignof_incomplete_type) 1890 << int(!isSizeof) << ExprRange)) 1891 return true; 1892 1893 // Reject sizeof(interface) and sizeof(interface<proto>) in 64-bit mode. 1894 if (LangOpts.ObjCNonFragileABI && exprType->isObjCInterfaceType()) { 1895 Diag(OpLoc, diag::err_sizeof_nonfragile_interface) 1896 << exprType << isSizeof << ExprRange; 1897 return true; 1898 } 1899 1900 return false; 1901} 1902 1903bool Sema::CheckAlignOfExpr(Expr *E, SourceLocation OpLoc, 1904 const SourceRange &ExprRange) { 1905 E = E->IgnoreParens(); 1906 1907 // alignof decl is always ok. 1908 if (isa<DeclRefExpr>(E)) 1909 return false; 1910 1911 // Cannot know anything else if the expression is dependent. 1912 if (E->isTypeDependent()) 1913 return false; 1914 1915 if (E->getBitField()) { 1916 Diag(OpLoc, diag::err_sizeof_alignof_bitfield) << 1 << ExprRange; 1917 return true; 1918 } 1919 1920 // Alignment of a field access is always okay, so long as it isn't a 1921 // bit-field. 1922 if (MemberExpr *ME = dyn_cast<MemberExpr>(E)) 1923 if (isa<FieldDecl>(ME->getMemberDecl())) 1924 return false; 1925 1926 return CheckSizeOfAlignOfOperand(E->getType(), OpLoc, ExprRange, false); 1927} 1928 1929/// \brief Build a sizeof or alignof expression given a type operand. 1930Action::OwningExprResult 1931Sema::CreateSizeOfAlignOfExpr(TypeSourceInfo *TInfo, 1932 SourceLocation OpLoc, 1933 bool isSizeOf, SourceRange R) { 1934 if (!TInfo) 1935 return ExprError(); 1936 1937 QualType T = TInfo->getType(); 1938 1939 if (!T->isDependentType() && 1940 CheckSizeOfAlignOfOperand(T, OpLoc, R, isSizeOf)) 1941 return ExprError(); 1942 1943 // C99 6.5.3.4p4: the type (an unsigned integer type) is size_t. 1944 return Owned(new (Context) SizeOfAlignOfExpr(isSizeOf, TInfo, 1945 Context.getSizeType(), OpLoc, 1946 R.getEnd())); 1947} 1948 1949/// \brief Build a sizeof or alignof expression given an expression 1950/// operand. 1951Action::OwningExprResult 1952Sema::CreateSizeOfAlignOfExpr(Expr *E, SourceLocation OpLoc, 1953 bool isSizeOf, SourceRange R) { 1954 // Verify that the operand is valid. 1955 bool isInvalid = false; 1956 if (E->isTypeDependent()) { 1957 // Delay type-checking for type-dependent expressions. 1958 } else if (!isSizeOf) { 1959 isInvalid = CheckAlignOfExpr(E, OpLoc, R); 1960 } else if (E->getBitField()) { // C99 6.5.3.4p1. 1961 Diag(OpLoc, diag::err_sizeof_alignof_bitfield) << 0; 1962 isInvalid = true; 1963 } else { 1964 isInvalid = CheckSizeOfAlignOfOperand(E->getType(), OpLoc, R, true); 1965 } 1966 1967 if (isInvalid) 1968 return ExprError(); 1969 1970 // C99 6.5.3.4p4: the type (an unsigned integer type) is size_t. 1971 return Owned(new (Context) SizeOfAlignOfExpr(isSizeOf, E, 1972 Context.getSizeType(), OpLoc, 1973 R.getEnd())); 1974} 1975 1976/// ActOnSizeOfAlignOfExpr - Handle @c sizeof(type) and @c sizeof @c expr and 1977/// the same for @c alignof and @c __alignof 1978/// Note that the ArgRange is invalid if isType is false. 1979Action::OwningExprResult 1980Sema::ActOnSizeOfAlignOfExpr(SourceLocation OpLoc, bool isSizeof, bool isType, 1981 void *TyOrEx, const SourceRange &ArgRange) { 1982 // If error parsing type, ignore. 1983 if (TyOrEx == 0) return ExprError(); 1984 1985 if (isType) { 1986 TypeSourceInfo *TInfo; 1987 (void) GetTypeFromParser(TyOrEx, &TInfo); 1988 return CreateSizeOfAlignOfExpr(TInfo, OpLoc, isSizeof, ArgRange); 1989 } 1990 1991 Expr *ArgEx = (Expr *)TyOrEx; 1992 Action::OwningExprResult Result 1993 = CreateSizeOfAlignOfExpr(ArgEx, OpLoc, isSizeof, ArgEx->getSourceRange()); 1994 1995 if (Result.isInvalid()) 1996 DeleteExpr(ArgEx); 1997 1998 return move(Result); 1999} 2000 2001QualType Sema::CheckRealImagOperand(Expr *&V, SourceLocation Loc, bool isReal) { 2002 if (V->isTypeDependent()) 2003 return Context.DependentTy; 2004 2005 // These operators return the element type of a complex type. 2006 if (const ComplexType *CT = V->getType()->getAs<ComplexType>()) 2007 return CT->getElementType(); 2008 2009 // Otherwise they pass through real integer and floating point types here. 2010 if (V->getType()->isArithmeticType()) 2011 return V->getType(); 2012 2013 // Reject anything else. 2014 Diag(Loc, diag::err_realimag_invalid_type) << V->getType() 2015 << (isReal ? "__real" : "__imag"); 2016 return QualType(); 2017} 2018 2019 2020 2021Action::OwningExprResult 2022Sema::ActOnPostfixUnaryOp(Scope *S, SourceLocation OpLoc, 2023 tok::TokenKind Kind, ExprArg Input) { 2024 UnaryOperator::Opcode Opc; 2025 switch (Kind) { 2026 default: assert(0 && "Unknown unary op!"); 2027 case tok::plusplus: Opc = UnaryOperator::PostInc; break; 2028 case tok::minusminus: Opc = UnaryOperator::PostDec; break; 2029 } 2030 2031 return BuildUnaryOp(S, OpLoc, Opc, move(Input)); 2032} 2033 2034Action::OwningExprResult 2035Sema::ActOnArraySubscriptExpr(Scope *S, ExprArg Base, SourceLocation LLoc, 2036 ExprArg Idx, SourceLocation RLoc) { 2037 // Since this might be a postfix expression, get rid of ParenListExprs. 2038 Base = MaybeConvertParenListExprToParenExpr(S, move(Base)); 2039 2040 Expr *LHSExp = static_cast<Expr*>(Base.get()), 2041 *RHSExp = static_cast<Expr*>(Idx.get()); 2042 2043 if (getLangOptions().CPlusPlus && 2044 (LHSExp->isTypeDependent() || RHSExp->isTypeDependent())) { 2045 Base.release(); 2046 Idx.release(); 2047 return Owned(new (Context) ArraySubscriptExpr(LHSExp, RHSExp, 2048 Context.DependentTy, RLoc)); 2049 } 2050 2051 if (getLangOptions().CPlusPlus && 2052 (LHSExp->getType()->isRecordType() || 2053 LHSExp->getType()->isEnumeralType() || 2054 RHSExp->getType()->isRecordType() || 2055 RHSExp->getType()->isEnumeralType())) { 2056 return CreateOverloadedArraySubscriptExpr(LLoc, RLoc, move(Base),move(Idx)); 2057 } 2058 2059 return CreateBuiltinArraySubscriptExpr(move(Base), LLoc, move(Idx), RLoc); 2060} 2061 2062 2063Action::OwningExprResult 2064Sema::CreateBuiltinArraySubscriptExpr(ExprArg Base, SourceLocation LLoc, 2065 ExprArg Idx, SourceLocation RLoc) { 2066 Expr *LHSExp = static_cast<Expr*>(Base.get()); 2067 Expr *RHSExp = static_cast<Expr*>(Idx.get()); 2068 2069 // Perform default conversions. 2070 if (!LHSExp->getType()->getAs<VectorType>()) 2071 DefaultFunctionArrayLvalueConversion(LHSExp); 2072 DefaultFunctionArrayLvalueConversion(RHSExp); 2073 2074 QualType LHSTy = LHSExp->getType(), RHSTy = RHSExp->getType(); 2075 2076 // C99 6.5.2.1p2: the expression e1[e2] is by definition precisely equivalent 2077 // to the expression *((e1)+(e2)). This means the array "Base" may actually be 2078 // in the subscript position. As a result, we need to derive the array base 2079 // and index from the expression types. 2080 Expr *BaseExpr, *IndexExpr; 2081 QualType ResultType; 2082 if (LHSTy->isDependentType() || RHSTy->isDependentType()) { 2083 BaseExpr = LHSExp; 2084 IndexExpr = RHSExp; 2085 ResultType = Context.DependentTy; 2086 } else if (const PointerType *PTy = LHSTy->getAs<PointerType>()) { 2087 BaseExpr = LHSExp; 2088 IndexExpr = RHSExp; 2089 ResultType = PTy->getPointeeType(); 2090 } else if (const PointerType *PTy = RHSTy->getAs<PointerType>()) { 2091 // Handle the uncommon case of "123[Ptr]". 2092 BaseExpr = RHSExp; 2093 IndexExpr = LHSExp; 2094 ResultType = PTy->getPointeeType(); 2095 } else if (const ObjCObjectPointerType *PTy = 2096 LHSTy->getAs<ObjCObjectPointerType>()) { 2097 BaseExpr = LHSExp; 2098 IndexExpr = RHSExp; 2099 ResultType = PTy->getPointeeType(); 2100 } else if (const ObjCObjectPointerType *PTy = 2101 RHSTy->getAs<ObjCObjectPointerType>()) { 2102 // Handle the uncommon case of "123[Ptr]". 2103 BaseExpr = RHSExp; 2104 IndexExpr = LHSExp; 2105 ResultType = PTy->getPointeeType(); 2106 } else if (const VectorType *VTy = LHSTy->getAs<VectorType>()) { 2107 BaseExpr = LHSExp; // vectors: V[123] 2108 IndexExpr = RHSExp; 2109 2110 // FIXME: need to deal with const... 2111 ResultType = VTy->getElementType(); 2112 } else if (LHSTy->isArrayType()) { 2113 // If we see an array that wasn't promoted by 2114 // DefaultFunctionArrayLvalueConversion, it must be an array that 2115 // wasn't promoted because of the C90 rule that doesn't 2116 // allow promoting non-lvalue arrays. Warn, then 2117 // force the promotion here. 2118 Diag(LHSExp->getLocStart(), diag::ext_subscript_non_lvalue) << 2119 LHSExp->getSourceRange(); 2120 ImpCastExprToType(LHSExp, Context.getArrayDecayedType(LHSTy), 2121 CastExpr::CK_ArrayToPointerDecay); 2122 LHSTy = LHSExp->getType(); 2123 2124 BaseExpr = LHSExp; 2125 IndexExpr = RHSExp; 2126 ResultType = LHSTy->getAs<PointerType>()->getPointeeType(); 2127 } else if (RHSTy->isArrayType()) { 2128 // Same as previous, except for 123[f().a] case 2129 Diag(RHSExp->getLocStart(), diag::ext_subscript_non_lvalue) << 2130 RHSExp->getSourceRange(); 2131 ImpCastExprToType(RHSExp, Context.getArrayDecayedType(RHSTy), 2132 CastExpr::CK_ArrayToPointerDecay); 2133 RHSTy = RHSExp->getType(); 2134 2135 BaseExpr = RHSExp; 2136 IndexExpr = LHSExp; 2137 ResultType = RHSTy->getAs<PointerType>()->getPointeeType(); 2138 } else { 2139 return ExprError(Diag(LLoc, diag::err_typecheck_subscript_value) 2140 << LHSExp->getSourceRange() << RHSExp->getSourceRange()); 2141 } 2142 // C99 6.5.2.1p1 2143 if (!(IndexExpr->getType()->isIntegerType() && 2144 IndexExpr->getType()->isScalarType()) && !IndexExpr->isTypeDependent()) 2145 return ExprError(Diag(LLoc, diag::err_typecheck_subscript_not_integer) 2146 << IndexExpr->getSourceRange()); 2147 2148 if ((IndexExpr->getType()->isSpecificBuiltinType(BuiltinType::Char_S) || 2149 IndexExpr->getType()->isSpecificBuiltinType(BuiltinType::Char_U)) 2150 && !IndexExpr->isTypeDependent()) 2151 Diag(LLoc, diag::warn_subscript_is_char) << IndexExpr->getSourceRange(); 2152 2153 // C99 6.5.2.1p1: "shall have type "pointer to *object* type". Similarly, 2154 // C++ [expr.sub]p1: The type "T" shall be a completely-defined object 2155 // type. Note that Functions are not objects, and that (in C99 parlance) 2156 // incomplete types are not object types. 2157 if (ResultType->isFunctionType()) { 2158 Diag(BaseExpr->getLocStart(), diag::err_subscript_function_type) 2159 << ResultType << BaseExpr->getSourceRange(); 2160 return ExprError(); 2161 } 2162 2163 if (!ResultType->isDependentType() && 2164 RequireCompleteType(LLoc, ResultType, 2165 PDiag(diag::err_subscript_incomplete_type) 2166 << BaseExpr->getSourceRange())) 2167 return ExprError(); 2168 2169 // Diagnose bad cases where we step over interface counts. 2170 if (ResultType->isObjCInterfaceType() && LangOpts.ObjCNonFragileABI) { 2171 Diag(LLoc, diag::err_subscript_nonfragile_interface) 2172 << ResultType << BaseExpr->getSourceRange(); 2173 return ExprError(); 2174 } 2175 2176 Base.release(); 2177 Idx.release(); 2178 return Owned(new (Context) ArraySubscriptExpr(LHSExp, RHSExp, 2179 ResultType, RLoc)); 2180} 2181 2182QualType Sema:: 2183CheckExtVectorComponent(QualType baseType, SourceLocation OpLoc, 2184 const IdentifierInfo *CompName, 2185 SourceLocation CompLoc) { 2186 // FIXME: Share logic with ExtVectorElementExpr::containsDuplicateElements, 2187 // see FIXME there. 2188 // 2189 // FIXME: This logic can be greatly simplified by splitting it along 2190 // halving/not halving and reworking the component checking. 2191 const ExtVectorType *vecType = baseType->getAs<ExtVectorType>(); 2192 2193 // The vector accessor can't exceed the number of elements. 2194 const char *compStr = CompName->getNameStart(); 2195 2196 // This flag determines whether or not the component is one of the four 2197 // special names that indicate a subset of exactly half the elements are 2198 // to be selected. 2199 bool HalvingSwizzle = false; 2200 2201 // This flag determines whether or not CompName has an 's' char prefix, 2202 // indicating that it is a string of hex values to be used as vector indices. 2203 bool HexSwizzle = *compStr == 's' || *compStr == 'S'; 2204 2205 // Check that we've found one of the special components, or that the component 2206 // names must come from the same set. 2207 if (!strcmp(compStr, "hi") || !strcmp(compStr, "lo") || 2208 !strcmp(compStr, "even") || !strcmp(compStr, "odd")) { 2209 HalvingSwizzle = true; 2210 } else if (vecType->getPointAccessorIdx(*compStr) != -1) { 2211 do 2212 compStr++; 2213 while (*compStr && vecType->getPointAccessorIdx(*compStr) != -1); 2214 } else if (HexSwizzle || vecType->getNumericAccessorIdx(*compStr) != -1) { 2215 do 2216 compStr++; 2217 while (*compStr && vecType->getNumericAccessorIdx(*compStr) != -1); 2218 } 2219 2220 if (!HalvingSwizzle && *compStr) { 2221 // We didn't get to the end of the string. This means the component names 2222 // didn't come from the same set *or* we encountered an illegal name. 2223 Diag(OpLoc, diag::err_ext_vector_component_name_illegal) 2224 << std::string(compStr,compStr+1) << SourceRange(CompLoc); 2225 return QualType(); 2226 } 2227 2228 // Ensure no component accessor exceeds the width of the vector type it 2229 // operates on. 2230 if (!HalvingSwizzle) { 2231 compStr = CompName->getNameStart(); 2232 2233 if (HexSwizzle) 2234 compStr++; 2235 2236 while (*compStr) { 2237 if (!vecType->isAccessorWithinNumElements(*compStr++)) { 2238 Diag(OpLoc, diag::err_ext_vector_component_exceeds_length) 2239 << baseType << SourceRange(CompLoc); 2240 return QualType(); 2241 } 2242 } 2243 } 2244 2245 // The component accessor looks fine - now we need to compute the actual type. 2246 // The vector type is implied by the component accessor. For example, 2247 // vec4.b is a float, vec4.xy is a vec2, vec4.rgb is a vec3, etc. 2248 // vec4.s0 is a float, vec4.s23 is a vec3, etc. 2249 // vec4.hi, vec4.lo, vec4.e, and vec4.o all return vec2. 2250 unsigned CompSize = HalvingSwizzle ? (vecType->getNumElements() + 1) / 2 2251 : CompName->getLength(); 2252 if (HexSwizzle) 2253 CompSize--; 2254 2255 if (CompSize == 1) 2256 return vecType->getElementType(); 2257 2258 QualType VT = Context.getExtVectorType(vecType->getElementType(), CompSize); 2259 // Now look up the TypeDefDecl from the vector type. Without this, 2260 // diagostics look bad. We want extended vector types to appear built-in. 2261 for (unsigned i = 0, E = ExtVectorDecls.size(); i != E; ++i) { 2262 if (ExtVectorDecls[i]->getUnderlyingType() == VT) 2263 return Context.getTypedefType(ExtVectorDecls[i]); 2264 } 2265 return VT; // should never get here (a typedef type should always be found). 2266} 2267 2268static Decl *FindGetterNameDeclFromProtocolList(const ObjCProtocolDecl*PDecl, 2269 IdentifierInfo *Member, 2270 const Selector &Sel, 2271 ASTContext &Context) { 2272 2273 if (ObjCPropertyDecl *PD = PDecl->FindPropertyDeclaration(Member)) 2274 return PD; 2275 if (ObjCMethodDecl *OMD = PDecl->getInstanceMethod(Sel)) 2276 return OMD; 2277 2278 for (ObjCProtocolDecl::protocol_iterator I = PDecl->protocol_begin(), 2279 E = PDecl->protocol_end(); I != E; ++I) { 2280 if (Decl *D = FindGetterNameDeclFromProtocolList(*I, Member, Sel, 2281 Context)) 2282 return D; 2283 } 2284 return 0; 2285} 2286 2287static Decl *FindGetterNameDecl(const ObjCObjectPointerType *QIdTy, 2288 IdentifierInfo *Member, 2289 const Selector &Sel, 2290 ASTContext &Context) { 2291 // Check protocols on qualified interfaces. 2292 Decl *GDecl = 0; 2293 for (ObjCObjectPointerType::qual_iterator I = QIdTy->qual_begin(), 2294 E = QIdTy->qual_end(); I != E; ++I) { 2295 if (ObjCPropertyDecl *PD = (*I)->FindPropertyDeclaration(Member)) { 2296 GDecl = PD; 2297 break; 2298 } 2299 // Also must look for a getter name which uses property syntax. 2300 if (ObjCMethodDecl *OMD = (*I)->getInstanceMethod(Sel)) { 2301 GDecl = OMD; 2302 break; 2303 } 2304 } 2305 if (!GDecl) { 2306 for (ObjCObjectPointerType::qual_iterator I = QIdTy->qual_begin(), 2307 E = QIdTy->qual_end(); I != E; ++I) { 2308 // Search in the protocol-qualifier list of current protocol. 2309 GDecl = FindGetterNameDeclFromProtocolList(*I, Member, Sel, Context); 2310 if (GDecl) 2311 return GDecl; 2312 } 2313 } 2314 return GDecl; 2315} 2316 2317Sema::OwningExprResult 2318Sema::ActOnDependentMemberExpr(ExprArg Base, QualType BaseType, 2319 bool IsArrow, SourceLocation OpLoc, 2320 const CXXScopeSpec &SS, 2321 NamedDecl *FirstQualifierInScope, 2322 DeclarationName Name, SourceLocation NameLoc, 2323 const TemplateArgumentListInfo *TemplateArgs) { 2324 Expr *BaseExpr = Base.takeAs<Expr>(); 2325 2326 // Even in dependent contexts, try to diagnose base expressions with 2327 // obviously wrong types, e.g.: 2328 // 2329 // T* t; 2330 // t.f; 2331 // 2332 // In Obj-C++, however, the above expression is valid, since it could be 2333 // accessing the 'f' property if T is an Obj-C interface. The extra check 2334 // allows this, while still reporting an error if T is a struct pointer. 2335 if (!IsArrow) { 2336 const PointerType *PT = BaseType->getAs<PointerType>(); 2337 if (PT && (!getLangOptions().ObjC1 || 2338 PT->getPointeeType()->isRecordType())) { 2339 assert(BaseExpr && "cannot happen with implicit member accesses"); 2340 Diag(NameLoc, diag::err_typecheck_member_reference_struct_union) 2341 << BaseType << BaseExpr->getSourceRange(); 2342 return ExprError(); 2343 } 2344 } 2345 2346 assert(BaseType->isDependentType() || Name.isDependentName()); 2347 2348 // Get the type being accessed in BaseType. If this is an arrow, the BaseExpr 2349 // must have pointer type, and the accessed type is the pointee. 2350 return Owned(CXXDependentScopeMemberExpr::Create(Context, BaseExpr, BaseType, 2351 IsArrow, OpLoc, 2352 static_cast<NestedNameSpecifier*>(SS.getScopeRep()), 2353 SS.getRange(), 2354 FirstQualifierInScope, 2355 Name, NameLoc, 2356 TemplateArgs)); 2357} 2358 2359/// We know that the given qualified member reference points only to 2360/// declarations which do not belong to the static type of the base 2361/// expression. Diagnose the problem. 2362static void DiagnoseQualifiedMemberReference(Sema &SemaRef, 2363 Expr *BaseExpr, 2364 QualType BaseType, 2365 const CXXScopeSpec &SS, 2366 const LookupResult &R) { 2367 // If this is an implicit member access, use a different set of 2368 // diagnostics. 2369 if (!BaseExpr) 2370 return DiagnoseInstanceReference(SemaRef, SS, R); 2371 2372 // FIXME: this is an exceedingly lame diagnostic for some of the more 2373 // complicated cases here. 2374 DeclContext *DC = R.getRepresentativeDecl()->getDeclContext(); 2375 SemaRef.Diag(R.getNameLoc(), diag::err_not_direct_base_or_virtual) 2376 << SS.getRange() << DC << BaseType; 2377} 2378 2379// Check whether the declarations we found through a nested-name 2380// specifier in a member expression are actually members of the base 2381// type. The restriction here is: 2382// 2383// C++ [expr.ref]p2: 2384// ... In these cases, the id-expression shall name a 2385// member of the class or of one of its base classes. 2386// 2387// So it's perfectly legitimate for the nested-name specifier to name 2388// an unrelated class, and for us to find an overload set including 2389// decls from classes which are not superclasses, as long as the decl 2390// we actually pick through overload resolution is from a superclass. 2391bool Sema::CheckQualifiedMemberReference(Expr *BaseExpr, 2392 QualType BaseType, 2393 const CXXScopeSpec &SS, 2394 const LookupResult &R) { 2395 const RecordType *BaseRT = BaseType->getAs<RecordType>(); 2396 if (!BaseRT) { 2397 // We can't check this yet because the base type is still 2398 // dependent. 2399 assert(BaseType->isDependentType()); 2400 return false; 2401 } 2402 CXXRecordDecl *BaseRecord = cast<CXXRecordDecl>(BaseRT->getDecl()); 2403 2404 for (LookupResult::iterator I = R.begin(), E = R.end(); I != E; ++I) { 2405 // If this is an implicit member reference and we find a 2406 // non-instance member, it's not an error. 2407 if (!BaseExpr && !IsInstanceMember((*I)->getUnderlyingDecl())) 2408 return false; 2409 2410 // Note that we use the DC of the decl, not the underlying decl. 2411 CXXRecordDecl *RecordD = cast<CXXRecordDecl>((*I)->getDeclContext()); 2412 while (RecordD->isAnonymousStructOrUnion()) 2413 RecordD = cast<CXXRecordDecl>(RecordD->getParent()); 2414 2415 llvm::SmallPtrSet<CXXRecordDecl*,4> MemberRecord; 2416 MemberRecord.insert(RecordD->getCanonicalDecl()); 2417 2418 if (!IsProvablyNotDerivedFrom(*this, BaseRecord, MemberRecord)) 2419 return false; 2420 } 2421 2422 DiagnoseQualifiedMemberReference(*this, BaseExpr, BaseType, SS, R); 2423 return true; 2424} 2425 2426static bool 2427LookupMemberExprInRecord(Sema &SemaRef, LookupResult &R, 2428 SourceRange BaseRange, const RecordType *RTy, 2429 SourceLocation OpLoc, const CXXScopeSpec &SS) { 2430 RecordDecl *RDecl = RTy->getDecl(); 2431 if (SemaRef.RequireCompleteType(OpLoc, QualType(RTy, 0), 2432 PDiag(diag::err_typecheck_incomplete_tag) 2433 << BaseRange)) 2434 return true; 2435 2436 DeclContext *DC = RDecl; 2437 if (SS.isSet()) { 2438 // If the member name was a qualified-id, look into the 2439 // nested-name-specifier. 2440 DC = SemaRef.computeDeclContext(SS, false); 2441 2442 if (SemaRef.RequireCompleteDeclContext(SS)) { 2443 SemaRef.Diag(SS.getRange().getEnd(), diag::err_typecheck_incomplete_tag) 2444 << SS.getRange() << DC; 2445 return true; 2446 } 2447 2448 assert(DC && "Cannot handle non-computable dependent contexts in lookup"); 2449 2450 if (!isa<TypeDecl>(DC)) { 2451 SemaRef.Diag(R.getNameLoc(), diag::err_qualified_member_nonclass) 2452 << DC << SS.getRange(); 2453 return true; 2454 } 2455 } 2456 2457 // The record definition is complete, now look up the member. 2458 SemaRef.LookupQualifiedName(R, DC); 2459 2460 if (!R.empty()) 2461 return false; 2462 2463 // We didn't find anything with the given name, so try to correct 2464 // for typos. 2465 DeclarationName Name = R.getLookupName(); 2466 if (SemaRef.CorrectTypo(R, 0, &SS, DC) && 2467 (isa<ValueDecl>(*R.begin()) || isa<FunctionTemplateDecl>(*R.begin()))) { 2468 SemaRef.Diag(R.getNameLoc(), diag::err_no_member_suggest) 2469 << Name << DC << R.getLookupName() << SS.getRange() 2470 << CodeModificationHint::CreateReplacement(R.getNameLoc(), 2471 R.getLookupName().getAsString()); 2472 if (NamedDecl *ND = R.getAsSingle<NamedDecl>()) 2473 SemaRef.Diag(ND->getLocation(), diag::note_previous_decl) 2474 << ND->getDeclName(); 2475 return false; 2476 } else { 2477 R.clear(); 2478 } 2479 2480 return false; 2481} 2482 2483Sema::OwningExprResult 2484Sema::BuildMemberReferenceExpr(ExprArg BaseArg, QualType BaseType, 2485 SourceLocation OpLoc, bool IsArrow, 2486 const CXXScopeSpec &SS, 2487 NamedDecl *FirstQualifierInScope, 2488 DeclarationName Name, SourceLocation NameLoc, 2489 const TemplateArgumentListInfo *TemplateArgs) { 2490 Expr *Base = BaseArg.takeAs<Expr>(); 2491 2492 if (BaseType->isDependentType() || 2493 (SS.isSet() && isDependentScopeSpecifier(SS))) 2494 return ActOnDependentMemberExpr(ExprArg(*this, Base), BaseType, 2495 IsArrow, OpLoc, 2496 SS, FirstQualifierInScope, 2497 Name, NameLoc, 2498 TemplateArgs); 2499 2500 LookupResult R(*this, Name, NameLoc, LookupMemberName); 2501 2502 // Implicit member accesses. 2503 if (!Base) { 2504 QualType RecordTy = BaseType; 2505 if (IsArrow) RecordTy = RecordTy->getAs<PointerType>()->getPointeeType(); 2506 if (LookupMemberExprInRecord(*this, R, SourceRange(), 2507 RecordTy->getAs<RecordType>(), 2508 OpLoc, SS)) 2509 return ExprError(); 2510 2511 // Explicit member accesses. 2512 } else { 2513 OwningExprResult Result = 2514 LookupMemberExpr(R, Base, IsArrow, OpLoc, 2515 SS, /*ObjCImpDecl*/ DeclPtrTy()); 2516 2517 if (Result.isInvalid()) { 2518 Owned(Base); 2519 return ExprError(); 2520 } 2521 2522 if (Result.get()) 2523 return move(Result); 2524 } 2525 2526 return BuildMemberReferenceExpr(ExprArg(*this, Base), BaseType, 2527 OpLoc, IsArrow, SS, FirstQualifierInScope, 2528 R, TemplateArgs); 2529} 2530 2531Sema::OwningExprResult 2532Sema::BuildMemberReferenceExpr(ExprArg Base, QualType BaseExprType, 2533 SourceLocation OpLoc, bool IsArrow, 2534 const CXXScopeSpec &SS, 2535 NamedDecl *FirstQualifierInScope, 2536 LookupResult &R, 2537 const TemplateArgumentListInfo *TemplateArgs) { 2538 Expr *BaseExpr = Base.takeAs<Expr>(); 2539 QualType BaseType = BaseExprType; 2540 if (IsArrow) { 2541 assert(BaseType->isPointerType()); 2542 BaseType = BaseType->getAs<PointerType>()->getPointeeType(); 2543 } 2544 2545 NestedNameSpecifier *Qualifier = 2546 static_cast<NestedNameSpecifier*>(SS.getScopeRep()); 2547 DeclarationName MemberName = R.getLookupName(); 2548 SourceLocation MemberLoc = R.getNameLoc(); 2549 2550 if (R.isAmbiguous()) 2551 return ExprError(); 2552 2553 if (R.empty()) { 2554 // Rederive where we looked up. 2555 DeclContext *DC = (SS.isSet() 2556 ? computeDeclContext(SS, false) 2557 : BaseType->getAs<RecordType>()->getDecl()); 2558 2559 Diag(R.getNameLoc(), diag::err_no_member) 2560 << MemberName << DC 2561 << (BaseExpr ? BaseExpr->getSourceRange() : SourceRange()); 2562 return ExprError(); 2563 } 2564 2565 // Diagnose lookups that find only declarations from a non-base 2566 // type. This is possible for either qualified lookups (which may 2567 // have been qualified with an unrelated type) or implicit member 2568 // expressions (which were found with unqualified lookup and thus 2569 // may have come from an enclosing scope). Note that it's okay for 2570 // lookup to find declarations from a non-base type as long as those 2571 // aren't the ones picked by overload resolution. 2572 if ((SS.isSet() || !BaseExpr || 2573 (isa<CXXThisExpr>(BaseExpr) && 2574 cast<CXXThisExpr>(BaseExpr)->isImplicit())) && 2575 CheckQualifiedMemberReference(BaseExpr, BaseType, SS, R)) 2576 return ExprError(); 2577 2578 // Construct an unresolved result if we in fact got an unresolved 2579 // result. 2580 if (R.isOverloadedResult() || R.isUnresolvableResult()) { 2581 bool Dependent = 2582 BaseExprType->isDependentType() || 2583 R.isUnresolvableResult() || 2584 OverloadExpr::ComputeDependence(R.begin(), R.end(), TemplateArgs); 2585 2586 // Suppress any lookup-related diagnostics; we'll do these when we 2587 // pick a member. 2588 R.suppressDiagnostics(); 2589 2590 UnresolvedMemberExpr *MemExpr 2591 = UnresolvedMemberExpr::Create(Context, Dependent, 2592 R.isUnresolvableResult(), 2593 BaseExpr, BaseExprType, 2594 IsArrow, OpLoc, 2595 Qualifier, SS.getRange(), 2596 MemberName, MemberLoc, 2597 TemplateArgs); 2598 MemExpr->addDecls(R.begin(), R.end()); 2599 2600 return Owned(MemExpr); 2601 } 2602 2603 assert(R.isSingleResult()); 2604 NamedDecl *MemberDecl = R.getFoundDecl(); 2605 2606 // FIXME: diagnose the presence of template arguments now. 2607 2608 // If the decl being referenced had an error, return an error for this 2609 // sub-expr without emitting another error, in order to avoid cascading 2610 // error cases. 2611 if (MemberDecl->isInvalidDecl()) 2612 return ExprError(); 2613 2614 // Handle the implicit-member-access case. 2615 if (!BaseExpr) { 2616 // If this is not an instance member, convert to a non-member access. 2617 if (!IsInstanceMember(MemberDecl)) 2618 return BuildDeclarationNameExpr(SS, R.getNameLoc(), MemberDecl); 2619 2620 SourceLocation Loc = R.getNameLoc(); 2621 if (SS.getRange().isValid()) 2622 Loc = SS.getRange().getBegin(); 2623 BaseExpr = new (Context) CXXThisExpr(Loc, BaseExprType,/*isImplicit=*/true); 2624 } 2625 2626 bool ShouldCheckUse = true; 2627 if (CXXMethodDecl *MD = dyn_cast<CXXMethodDecl>(MemberDecl)) { 2628 // Don't diagnose the use of a virtual member function unless it's 2629 // explicitly qualified. 2630 if (MD->isVirtual() && !SS.isSet()) 2631 ShouldCheckUse = false; 2632 } 2633 2634 // Check the use of this member. 2635 if (ShouldCheckUse && DiagnoseUseOfDecl(MemberDecl, MemberLoc)) { 2636 Owned(BaseExpr); 2637 return ExprError(); 2638 } 2639 2640 if (FieldDecl *FD = dyn_cast<FieldDecl>(MemberDecl)) { 2641 // We may have found a field within an anonymous union or struct 2642 // (C++ [class.union]). 2643 if (cast<RecordDecl>(FD->getDeclContext())->isAnonymousStructOrUnion() && 2644 !BaseType->getAs<RecordType>()->getDecl()->isAnonymousStructOrUnion()) 2645 return BuildAnonymousStructUnionMemberReference(MemberLoc, FD, 2646 BaseExpr, OpLoc); 2647 2648 // Figure out the type of the member; see C99 6.5.2.3p3, C++ [expr.ref] 2649 QualType MemberType = FD->getType(); 2650 if (const ReferenceType *Ref = MemberType->getAs<ReferenceType>()) 2651 MemberType = Ref->getPointeeType(); 2652 else { 2653 Qualifiers BaseQuals = BaseType.getQualifiers(); 2654 BaseQuals.removeObjCGCAttr(); 2655 if (FD->isMutable()) BaseQuals.removeConst(); 2656 2657 Qualifiers MemberQuals 2658 = Context.getCanonicalType(MemberType).getQualifiers(); 2659 2660 Qualifiers Combined = BaseQuals + MemberQuals; 2661 if (Combined != MemberQuals) 2662 MemberType = Context.getQualifiedType(MemberType, Combined); 2663 } 2664 2665 MarkDeclarationReferenced(MemberLoc, FD); 2666 if (PerformObjectMemberConversion(BaseExpr, FD)) 2667 return ExprError(); 2668 return Owned(BuildMemberExpr(Context, BaseExpr, IsArrow, SS, 2669 FD, MemberLoc, MemberType)); 2670 } 2671 2672 if (VarDecl *Var = dyn_cast<VarDecl>(MemberDecl)) { 2673 MarkDeclarationReferenced(MemberLoc, Var); 2674 return Owned(BuildMemberExpr(Context, BaseExpr, IsArrow, SS, 2675 Var, MemberLoc, 2676 Var->getType().getNonReferenceType())); 2677 } 2678 2679 if (FunctionDecl *MemberFn = dyn_cast<FunctionDecl>(MemberDecl)) { 2680 MarkDeclarationReferenced(MemberLoc, MemberDecl); 2681 return Owned(BuildMemberExpr(Context, BaseExpr, IsArrow, SS, 2682 MemberFn, MemberLoc, 2683 MemberFn->getType())); 2684 } 2685 2686 if (EnumConstantDecl *Enum = dyn_cast<EnumConstantDecl>(MemberDecl)) { 2687 MarkDeclarationReferenced(MemberLoc, MemberDecl); 2688 return Owned(BuildMemberExpr(Context, BaseExpr, IsArrow, SS, 2689 Enum, MemberLoc, Enum->getType())); 2690 } 2691 2692 Owned(BaseExpr); 2693 2694 if (isa<TypeDecl>(MemberDecl)) 2695 return ExprError(Diag(MemberLoc,diag::err_typecheck_member_reference_type) 2696 << MemberName << int(IsArrow)); 2697 2698 // We found a declaration kind that we didn't expect. This is a 2699 // generic error message that tells the user that she can't refer 2700 // to this member with '.' or '->'. 2701 return ExprError(Diag(MemberLoc, 2702 diag::err_typecheck_member_reference_unknown) 2703 << MemberName << int(IsArrow)); 2704} 2705 2706/// Look up the given member of the given non-type-dependent 2707/// expression. This can return in one of two ways: 2708/// * If it returns a sentinel null-but-valid result, the caller will 2709/// assume that lookup was performed and the results written into 2710/// the provided structure. It will take over from there. 2711/// * Otherwise, the returned expression will be produced in place of 2712/// an ordinary member expression. 2713/// 2714/// The ObjCImpDecl bit is a gross hack that will need to be properly 2715/// fixed for ObjC++. 2716Sema::OwningExprResult 2717Sema::LookupMemberExpr(LookupResult &R, Expr *&BaseExpr, 2718 bool &IsArrow, SourceLocation OpLoc, 2719 const CXXScopeSpec &SS, 2720 DeclPtrTy ObjCImpDecl) { 2721 assert(BaseExpr && "no base expression"); 2722 2723 // Perform default conversions. 2724 DefaultFunctionArrayConversion(BaseExpr); 2725 2726 QualType BaseType = BaseExpr->getType(); 2727 assert(!BaseType->isDependentType()); 2728 2729 DeclarationName MemberName = R.getLookupName(); 2730 SourceLocation MemberLoc = R.getNameLoc(); 2731 2732 // If the user is trying to apply -> or . to a function pointer 2733 // type, it's probably because they forgot parentheses to call that 2734 // function. Suggest the addition of those parentheses, build the 2735 // call, and continue on. 2736 if (const PointerType *Ptr = BaseType->getAs<PointerType>()) { 2737 if (const FunctionProtoType *Fun 2738 = Ptr->getPointeeType()->getAs<FunctionProtoType>()) { 2739 QualType ResultTy = Fun->getResultType(); 2740 if (Fun->getNumArgs() == 0 && 2741 ((!IsArrow && ResultTy->isRecordType()) || 2742 (IsArrow && ResultTy->isPointerType() && 2743 ResultTy->getAs<PointerType>()->getPointeeType() 2744 ->isRecordType()))) { 2745 SourceLocation Loc = PP.getLocForEndOfToken(BaseExpr->getLocEnd()); 2746 Diag(Loc, diag::err_member_reference_needs_call) 2747 << QualType(Fun, 0) 2748 << CodeModificationHint::CreateInsertion(Loc, "()"); 2749 2750 OwningExprResult NewBase 2751 = ActOnCallExpr(0, ExprArg(*this, BaseExpr), Loc, 2752 MultiExprArg(*this, 0, 0), 0, Loc); 2753 if (NewBase.isInvalid()) 2754 return ExprError(); 2755 2756 BaseExpr = NewBase.takeAs<Expr>(); 2757 DefaultFunctionArrayConversion(BaseExpr); 2758 BaseType = BaseExpr->getType(); 2759 } 2760 } 2761 } 2762 2763 // If this is an Objective-C pseudo-builtin and a definition is provided then 2764 // use that. 2765 if (BaseType->isObjCIdType()) { 2766 if (IsArrow) { 2767 // Handle the following exceptional case PObj->isa. 2768 if (const ObjCObjectPointerType *OPT = 2769 BaseType->getAs<ObjCObjectPointerType>()) { 2770 if (OPT->getPointeeType()->isSpecificBuiltinType(BuiltinType::ObjCId) && 2771 MemberName.getAsIdentifierInfo()->isStr("isa")) 2772 return Owned(new (Context) ObjCIsaExpr(BaseExpr, true, MemberLoc, 2773 Context.getObjCClassType())); 2774 } 2775 } 2776 // We have an 'id' type. Rather than fall through, we check if this 2777 // is a reference to 'isa'. 2778 if (BaseType != Context.ObjCIdRedefinitionType) { 2779 BaseType = Context.ObjCIdRedefinitionType; 2780 ImpCastExprToType(BaseExpr, BaseType, CastExpr::CK_BitCast); 2781 } 2782 } 2783 2784 // If this is an Objective-C pseudo-builtin and a definition is provided then 2785 // use that. 2786 if (Context.isObjCSelType(BaseType)) { 2787 // We have an 'SEL' type. Rather than fall through, we check if this 2788 // is a reference to 'sel_id'. 2789 if (BaseType != Context.ObjCSelRedefinitionType) { 2790 BaseType = Context.ObjCSelRedefinitionType; 2791 ImpCastExprToType(BaseExpr, BaseType, CastExpr::CK_BitCast); 2792 } 2793 } 2794 2795 assert(!BaseType.isNull() && "no type for member expression"); 2796 2797 // Handle properties on ObjC 'Class' types. 2798 if (!IsArrow && BaseType->isObjCClassType()) { 2799 // Also must look for a getter name which uses property syntax. 2800 IdentifierInfo *Member = MemberName.getAsIdentifierInfo(); 2801 Selector Sel = PP.getSelectorTable().getNullarySelector(Member); 2802 if (ObjCMethodDecl *MD = getCurMethodDecl()) { 2803 ObjCInterfaceDecl *IFace = MD->getClassInterface(); 2804 ObjCMethodDecl *Getter; 2805 // FIXME: need to also look locally in the implementation. 2806 if ((Getter = IFace->lookupClassMethod(Sel))) { 2807 // Check the use of this method. 2808 if (DiagnoseUseOfDecl(Getter, MemberLoc)) 2809 return ExprError(); 2810 } 2811 // If we found a getter then this may be a valid dot-reference, we 2812 // will look for the matching setter, in case it is needed. 2813 Selector SetterSel = 2814 SelectorTable::constructSetterName(PP.getIdentifierTable(), 2815 PP.getSelectorTable(), Member); 2816 ObjCMethodDecl *Setter = IFace->lookupClassMethod(SetterSel); 2817 if (!Setter) { 2818 // If this reference is in an @implementation, also check for 'private' 2819 // methods. 2820 Setter = IFace->lookupPrivateInstanceMethod(SetterSel); 2821 } 2822 // Look through local category implementations associated with the class. 2823 if (!Setter) 2824 Setter = IFace->getCategoryClassMethod(SetterSel); 2825 2826 if (Setter && DiagnoseUseOfDecl(Setter, MemberLoc)) 2827 return ExprError(); 2828 2829 if (Getter || Setter) { 2830 QualType PType; 2831 2832 if (Getter) 2833 PType = Getter->getResultType(); 2834 else 2835 // Get the expression type from Setter's incoming parameter. 2836 PType = (*(Setter->param_end() -1))->getType(); 2837 // FIXME: we must check that the setter has property type. 2838 return Owned(new (Context) ObjCImplicitSetterGetterRefExpr(Getter, 2839 PType, 2840 Setter, MemberLoc, BaseExpr)); 2841 } 2842 return ExprError(Diag(MemberLoc, diag::err_property_not_found) 2843 << MemberName << BaseType); 2844 } 2845 } 2846 2847 if (BaseType->isObjCClassType() && 2848 BaseType != Context.ObjCClassRedefinitionType) { 2849 BaseType = Context.ObjCClassRedefinitionType; 2850 ImpCastExprToType(BaseExpr, BaseType, CastExpr::CK_BitCast); 2851 } 2852 2853 if (IsArrow) { 2854 if (const PointerType *PT = BaseType->getAs<PointerType>()) 2855 BaseType = PT->getPointeeType(); 2856 else if (BaseType->isObjCObjectPointerType()) 2857 ; 2858 else if (BaseType->isRecordType()) { 2859 // Recover from arrow accesses to records, e.g.: 2860 // struct MyRecord foo; 2861 // foo->bar 2862 // This is actually well-formed in C++ if MyRecord has an 2863 // overloaded operator->, but that should have been dealt with 2864 // by now. 2865 Diag(OpLoc, diag::err_typecheck_member_reference_suggestion) 2866 << BaseType << int(IsArrow) << BaseExpr->getSourceRange() 2867 << CodeModificationHint::CreateReplacement(OpLoc, "."); 2868 IsArrow = false; 2869 } else { 2870 Diag(MemberLoc, diag::err_typecheck_member_reference_arrow) 2871 << BaseType << BaseExpr->getSourceRange(); 2872 return ExprError(); 2873 } 2874 } else { 2875 // Recover from dot accesses to pointers, e.g.: 2876 // type *foo; 2877 // foo.bar 2878 // This is actually well-formed in two cases: 2879 // - 'type' is an Objective C type 2880 // - 'bar' is a pseudo-destructor name which happens to refer to 2881 // the appropriate pointer type 2882 if (MemberName.getNameKind() != DeclarationName::CXXDestructorName) { 2883 const PointerType *PT = BaseType->getAs<PointerType>(); 2884 if (PT && PT->getPointeeType()->isRecordType()) { 2885 Diag(OpLoc, diag::err_typecheck_member_reference_suggestion) 2886 << BaseType << int(IsArrow) << BaseExpr->getSourceRange() 2887 << CodeModificationHint::CreateReplacement(OpLoc, "->"); 2888 BaseType = PT->getPointeeType(); 2889 IsArrow = true; 2890 } 2891 } 2892 } 2893 2894 // Handle field access to simple records. This also handles access 2895 // to fields of the ObjC 'id' struct. 2896 if (const RecordType *RTy = BaseType->getAs<RecordType>()) { 2897 if (LookupMemberExprInRecord(*this, R, BaseExpr->getSourceRange(), 2898 RTy, OpLoc, SS)) 2899 return ExprError(); 2900 return Owned((Expr*) 0); 2901 } 2902 2903 // Handle pseudo-destructors (C++ [expr.pseudo]). Since anything referring 2904 // into a record type was handled above, any destructor we see here is a 2905 // pseudo-destructor. 2906 if (MemberName.getNameKind() == DeclarationName::CXXDestructorName) { 2907 // C++ [expr.pseudo]p2: 2908 // The left hand side of the dot operator shall be of scalar type. The 2909 // left hand side of the arrow operator shall be of pointer to scalar 2910 // type. 2911 if (!BaseType->isScalarType()) 2912 return Owned(Diag(OpLoc, diag::err_pseudo_dtor_base_not_scalar) 2913 << BaseType << BaseExpr->getSourceRange()); 2914 2915 // [...] The type designated by the pseudo-destructor-name shall be the 2916 // same as the object type. 2917 if (!MemberName.getCXXNameType()->isDependentType() && 2918 !Context.hasSameUnqualifiedType(BaseType, MemberName.getCXXNameType())) 2919 return Owned(Diag(OpLoc, diag::err_pseudo_dtor_type_mismatch) 2920 << BaseType << MemberName.getCXXNameType() 2921 << BaseExpr->getSourceRange() << SourceRange(MemberLoc)); 2922 2923 // [...] Furthermore, the two type-names in a pseudo-destructor-name of 2924 // the form 2925 // 2926 // ::[opt] nested-name-specifier[opt] type-name :: ̃ type-name 2927 // 2928 // shall designate the same scalar type. 2929 // 2930 // FIXME: DPG can't see any way to trigger this particular clause, so it 2931 // isn't checked here. 2932 2933 // FIXME: We've lost the precise spelling of the type by going through 2934 // DeclarationName. Can we do better? 2935 return Owned(new (Context) CXXPseudoDestructorExpr(Context, BaseExpr, 2936 IsArrow, OpLoc, 2937 (NestedNameSpecifier *) SS.getScopeRep(), 2938 SS.getRange(), 2939 MemberName.getCXXNameType(), 2940 MemberLoc)); 2941 } 2942 2943 // Handle access to Objective-C instance variables, such as "Obj->ivar" and 2944 // (*Obj).ivar. 2945 if ((IsArrow && BaseType->isObjCObjectPointerType()) || 2946 (!IsArrow && BaseType->isObjCInterfaceType())) { 2947 const ObjCObjectPointerType *OPT = BaseType->getAs<ObjCObjectPointerType>(); 2948 const ObjCInterfaceType *IFaceT = 2949 OPT ? OPT->getInterfaceType() : BaseType->getAs<ObjCInterfaceType>(); 2950 if (IFaceT) { 2951 IdentifierInfo *Member = MemberName.getAsIdentifierInfo(); 2952 2953 ObjCInterfaceDecl *IDecl = IFaceT->getDecl(); 2954 ObjCInterfaceDecl *ClassDeclared; 2955 ObjCIvarDecl *IV = IDecl->lookupInstanceVariable(Member, ClassDeclared); 2956 2957 if (!IV) { 2958 // Attempt to correct for typos in ivar names. 2959 LookupResult Res(*this, R.getLookupName(), R.getNameLoc(), 2960 LookupMemberName); 2961 if (CorrectTypo(Res, 0, 0, IDecl) && 2962 (IV = Res.getAsSingle<ObjCIvarDecl>())) { 2963 Diag(R.getNameLoc(), 2964 diag::err_typecheck_member_reference_ivar_suggest) 2965 << IDecl->getDeclName() << MemberName << IV->getDeclName() 2966 << CodeModificationHint::CreateReplacement(R.getNameLoc(), 2967 IV->getNameAsString()); 2968 Diag(IV->getLocation(), diag::note_previous_decl) 2969 << IV->getDeclName(); 2970 } 2971 } 2972 2973 if (IV) { 2974 // If the decl being referenced had an error, return an error for this 2975 // sub-expr without emitting another error, in order to avoid cascading 2976 // error cases. 2977 if (IV->isInvalidDecl()) 2978 return ExprError(); 2979 2980 // Check whether we can reference this field. 2981 if (DiagnoseUseOfDecl(IV, MemberLoc)) 2982 return ExprError(); 2983 if (IV->getAccessControl() != ObjCIvarDecl::Public && 2984 IV->getAccessControl() != ObjCIvarDecl::Package) { 2985 ObjCInterfaceDecl *ClassOfMethodDecl = 0; 2986 if (ObjCMethodDecl *MD = getCurMethodDecl()) 2987 ClassOfMethodDecl = MD->getClassInterface(); 2988 else if (ObjCImpDecl && getCurFunctionDecl()) { 2989 // Case of a c-function declared inside an objc implementation. 2990 // FIXME: For a c-style function nested inside an objc implementation 2991 // class, there is no implementation context available, so we pass 2992 // down the context as argument to this routine. Ideally, this context 2993 // need be passed down in the AST node and somehow calculated from the 2994 // AST for a function decl. 2995 Decl *ImplDecl = ObjCImpDecl.getAs<Decl>(); 2996 if (ObjCImplementationDecl *IMPD = 2997 dyn_cast<ObjCImplementationDecl>(ImplDecl)) 2998 ClassOfMethodDecl = IMPD->getClassInterface(); 2999 else if (ObjCCategoryImplDecl* CatImplClass = 3000 dyn_cast<ObjCCategoryImplDecl>(ImplDecl)) 3001 ClassOfMethodDecl = CatImplClass->getClassInterface(); 3002 } 3003 3004 if (IV->getAccessControl() == ObjCIvarDecl::Private) { 3005 if (ClassDeclared != IDecl || 3006 ClassOfMethodDecl != ClassDeclared) 3007 Diag(MemberLoc, diag::error_private_ivar_access) 3008 << IV->getDeclName(); 3009 } else if (!IDecl->isSuperClassOf(ClassOfMethodDecl)) 3010 // @protected 3011 Diag(MemberLoc, diag::error_protected_ivar_access) 3012 << IV->getDeclName(); 3013 } 3014 3015 return Owned(new (Context) ObjCIvarRefExpr(IV, IV->getType(), 3016 MemberLoc, BaseExpr, 3017 IsArrow)); 3018 } 3019 return ExprError(Diag(MemberLoc, diag::err_typecheck_member_reference_ivar) 3020 << IDecl->getDeclName() << MemberName 3021 << BaseExpr->getSourceRange()); 3022 } 3023 } 3024 // Handle properties on 'id' and qualified "id". 3025 if (!IsArrow && (BaseType->isObjCIdType() || 3026 BaseType->isObjCQualifiedIdType())) { 3027 const ObjCObjectPointerType *QIdTy = BaseType->getAs<ObjCObjectPointerType>(); 3028 IdentifierInfo *Member = MemberName.getAsIdentifierInfo(); 3029 3030 // Check protocols on qualified interfaces. 3031 Selector Sel = PP.getSelectorTable().getNullarySelector(Member); 3032 if (Decl *PMDecl = FindGetterNameDecl(QIdTy, Member, Sel, Context)) { 3033 if (ObjCPropertyDecl *PD = dyn_cast<ObjCPropertyDecl>(PMDecl)) { 3034 // Check the use of this declaration 3035 if (DiagnoseUseOfDecl(PD, MemberLoc)) 3036 return ExprError(); 3037 3038 return Owned(new (Context) ObjCPropertyRefExpr(PD, PD->getType(), 3039 MemberLoc, BaseExpr)); 3040 } 3041 if (ObjCMethodDecl *OMD = dyn_cast<ObjCMethodDecl>(PMDecl)) { 3042 // Check the use of this method. 3043 if (DiagnoseUseOfDecl(OMD, MemberLoc)) 3044 return ExprError(); 3045 3046 return Owned(new (Context) ObjCMessageExpr(Context, BaseExpr, Sel, 3047 OMD->getResultType(), 3048 OMD, OpLoc, MemberLoc, 3049 NULL, 0)); 3050 } 3051 } 3052 3053 return ExprError(Diag(MemberLoc, diag::err_property_not_found) 3054 << MemberName << BaseType); 3055 } 3056 // Handle Objective-C property access, which is "Obj.property" where Obj is a 3057 // pointer to a (potentially qualified) interface type. 3058 const ObjCObjectPointerType *OPT; 3059 if (!IsArrow && (OPT = BaseType->getAsObjCInterfacePointerType())) { 3060 const ObjCInterfaceType *IFaceT = OPT->getInterfaceType(); 3061 ObjCInterfaceDecl *IFace = IFaceT->getDecl(); 3062 IdentifierInfo *Member = MemberName.getAsIdentifierInfo(); 3063 3064 // Search for a declared property first. 3065 if (ObjCPropertyDecl *PD = IFace->FindPropertyDeclaration(Member)) { 3066 // Check whether we can reference this property. 3067 if (DiagnoseUseOfDecl(PD, MemberLoc)) 3068 return ExprError(); 3069 QualType ResTy = PD->getType(); 3070 Selector Sel = PP.getSelectorTable().getNullarySelector(Member); 3071 ObjCMethodDecl *Getter = IFace->lookupInstanceMethod(Sel); 3072 if (DiagnosePropertyAccessorMismatch(PD, Getter, MemberLoc)) 3073 ResTy = Getter->getResultType(); 3074 return Owned(new (Context) ObjCPropertyRefExpr(PD, ResTy, 3075 MemberLoc, BaseExpr)); 3076 } 3077 // Check protocols on qualified interfaces. 3078 for (ObjCObjectPointerType::qual_iterator I = OPT->qual_begin(), 3079 E = OPT->qual_end(); I != E; ++I) 3080 if (ObjCPropertyDecl *PD = (*I)->FindPropertyDeclaration(Member)) { 3081 // Check whether we can reference this property. 3082 if (DiagnoseUseOfDecl(PD, MemberLoc)) 3083 return ExprError(); 3084 3085 return Owned(new (Context) ObjCPropertyRefExpr(PD, PD->getType(), 3086 MemberLoc, BaseExpr)); 3087 } 3088 // If that failed, look for an "implicit" property by seeing if the nullary 3089 // selector is implemented. 3090 3091 // FIXME: The logic for looking up nullary and unary selectors should be 3092 // shared with the code in ActOnInstanceMessage. 3093 3094 Selector Sel = PP.getSelectorTable().getNullarySelector(Member); 3095 ObjCMethodDecl *Getter = IFace->lookupInstanceMethod(Sel); 3096 3097 // If this reference is in an @implementation, check for 'private' methods. 3098 if (!Getter) 3099 Getter = IFace->lookupPrivateInstanceMethod(Sel); 3100 3101 // Look through local category implementations associated with the class. 3102 if (!Getter) 3103 Getter = IFace->getCategoryInstanceMethod(Sel); 3104 if (Getter) { 3105 // Check if we can reference this property. 3106 if (DiagnoseUseOfDecl(Getter, MemberLoc)) 3107 return ExprError(); 3108 } 3109 // If we found a getter then this may be a valid dot-reference, we 3110 // will look for the matching setter, in case it is needed. 3111 Selector SetterSel = 3112 SelectorTable::constructSetterName(PP.getIdentifierTable(), 3113 PP.getSelectorTable(), Member); 3114 ObjCMethodDecl *Setter = IFace->lookupInstanceMethod(SetterSel); 3115 if (!Setter) { 3116 // If this reference is in an @implementation, also check for 'private' 3117 // methods. 3118 Setter = IFace->lookupPrivateInstanceMethod(SetterSel); 3119 } 3120 // Look through local category implementations associated with the class. 3121 if (!Setter) 3122 Setter = IFace->getCategoryInstanceMethod(SetterSel); 3123 3124 if (Setter && DiagnoseUseOfDecl(Setter, MemberLoc)) 3125 return ExprError(); 3126 3127 if (Getter) { 3128 QualType PType; 3129 PType = Getter->getResultType(); 3130 return Owned(new (Context) ObjCImplicitSetterGetterRefExpr(Getter, PType, 3131 Setter, MemberLoc, BaseExpr)); 3132 } 3133 3134 // Attempt to correct for typos in property names. 3135 LookupResult Res(*this, R.getLookupName(), R.getNameLoc(), 3136 LookupOrdinaryName); 3137 if (CorrectTypo(Res, 0, 0, IFace, false, OPT) && 3138 Res.getAsSingle<ObjCPropertyDecl>()) { 3139 Diag(R.getNameLoc(), diag::err_property_not_found_suggest) 3140 << MemberName << BaseType << Res.getLookupName() 3141 << CodeModificationHint::CreateReplacement(R.getNameLoc(), 3142 Res.getLookupName().getAsString()); 3143 ObjCPropertyDecl *Property = Res.getAsSingle<ObjCPropertyDecl>(); 3144 Diag(Property->getLocation(), diag::note_previous_decl) 3145 << Property->getDeclName(); 3146 3147 return LookupMemberExpr(Res, BaseExpr, IsArrow, OpLoc, SS, 3148 ObjCImpDecl); 3149 } 3150 Diag(MemberLoc, diag::err_property_not_found) 3151 << MemberName << BaseType; 3152 if (Setter && !Getter) 3153 Diag(Setter->getLocation(), diag::note_getter_unavailable) 3154 << MemberName << BaseExpr->getSourceRange(); 3155 return ExprError(); 3156 } 3157 3158 // Handle the following exceptional case (*Obj).isa. 3159 if (!IsArrow && 3160 BaseType->isSpecificBuiltinType(BuiltinType::ObjCId) && 3161 MemberName.getAsIdentifierInfo()->isStr("isa")) 3162 return Owned(new (Context) ObjCIsaExpr(BaseExpr, false, MemberLoc, 3163 Context.getObjCClassType())); 3164 3165 // Handle 'field access' to vectors, such as 'V.xx'. 3166 if (BaseType->isExtVectorType()) { 3167 IdentifierInfo *Member = MemberName.getAsIdentifierInfo(); 3168 QualType ret = CheckExtVectorComponent(BaseType, OpLoc, Member, MemberLoc); 3169 if (ret.isNull()) 3170 return ExprError(); 3171 return Owned(new (Context) ExtVectorElementExpr(ret, BaseExpr, *Member, 3172 MemberLoc)); 3173 } 3174 3175 Diag(MemberLoc, diag::err_typecheck_member_reference_struct_union) 3176 << BaseType << BaseExpr->getSourceRange(); 3177 3178 return ExprError(); 3179} 3180 3181/// The main callback when the parser finds something like 3182/// expression . [nested-name-specifier] identifier 3183/// expression -> [nested-name-specifier] identifier 3184/// where 'identifier' encompasses a fairly broad spectrum of 3185/// possibilities, including destructor and operator references. 3186/// 3187/// \param OpKind either tok::arrow or tok::period 3188/// \param HasTrailingLParen whether the next token is '(', which 3189/// is used to diagnose mis-uses of special members that can 3190/// only be called 3191/// \param ObjCImpDecl the current ObjC @implementation decl; 3192/// this is an ugly hack around the fact that ObjC @implementations 3193/// aren't properly put in the context chain 3194Sema::OwningExprResult Sema::ActOnMemberAccessExpr(Scope *S, ExprArg BaseArg, 3195 SourceLocation OpLoc, 3196 tok::TokenKind OpKind, 3197 const CXXScopeSpec &SS, 3198 UnqualifiedId &Id, 3199 DeclPtrTy ObjCImpDecl, 3200 bool HasTrailingLParen) { 3201 if (SS.isSet() && SS.isInvalid()) 3202 return ExprError(); 3203 3204 TemplateArgumentListInfo TemplateArgsBuffer; 3205 3206 // Decompose the name into its component parts. 3207 DeclarationName Name; 3208 SourceLocation NameLoc; 3209 const TemplateArgumentListInfo *TemplateArgs; 3210 DecomposeUnqualifiedId(*this, Id, TemplateArgsBuffer, 3211 Name, NameLoc, TemplateArgs); 3212 3213 bool IsArrow = (OpKind == tok::arrow); 3214 3215 NamedDecl *FirstQualifierInScope 3216 = (!SS.isSet() ? 0 : FindFirstQualifierInScope(S, 3217 static_cast<NestedNameSpecifier*>(SS.getScopeRep()))); 3218 3219 // This is a postfix expression, so get rid of ParenListExprs. 3220 BaseArg = MaybeConvertParenListExprToParenExpr(S, move(BaseArg)); 3221 3222 Expr *Base = BaseArg.takeAs<Expr>(); 3223 OwningExprResult Result(*this); 3224 if (Base->getType()->isDependentType() || Name.isDependentName()) { 3225 Result = ActOnDependentMemberExpr(ExprArg(*this, Base), Base->getType(), 3226 IsArrow, OpLoc, 3227 SS, FirstQualifierInScope, 3228 Name, NameLoc, 3229 TemplateArgs); 3230 } else { 3231 LookupResult R(*this, Name, NameLoc, LookupMemberName); 3232 if (TemplateArgs) { 3233 // Re-use the lookup done for the template name. 3234 DecomposeTemplateName(R, Id); 3235 } else { 3236 Result = LookupMemberExpr(R, Base, IsArrow, OpLoc, 3237 SS, ObjCImpDecl); 3238 3239 if (Result.isInvalid()) { 3240 Owned(Base); 3241 return ExprError(); 3242 } 3243 3244 if (Result.get()) { 3245 // The only way a reference to a destructor can be used is to 3246 // immediately call it, which falls into this case. If the 3247 // next token is not a '(', produce a diagnostic and build the 3248 // call now. 3249 if (!HasTrailingLParen && 3250 Id.getKind() == UnqualifiedId::IK_DestructorName) 3251 return DiagnoseDtorReference(NameLoc, move(Result)); 3252 3253 return move(Result); 3254 } 3255 } 3256 3257 Result = BuildMemberReferenceExpr(ExprArg(*this, Base), Base->getType(), 3258 OpLoc, IsArrow, SS, FirstQualifierInScope, 3259 R, TemplateArgs); 3260 } 3261 3262 return move(Result); 3263} 3264 3265Sema::OwningExprResult Sema::BuildCXXDefaultArgExpr(SourceLocation CallLoc, 3266 FunctionDecl *FD, 3267 ParmVarDecl *Param) { 3268 if (Param->hasUnparsedDefaultArg()) { 3269 Diag (CallLoc, 3270 diag::err_use_of_default_argument_to_function_declared_later) << 3271 FD << cast<CXXRecordDecl>(FD->getDeclContext())->getDeclName(); 3272 Diag(UnparsedDefaultArgLocs[Param], 3273 diag::note_default_argument_declared_here); 3274 } else { 3275 if (Param->hasUninstantiatedDefaultArg()) { 3276 Expr *UninstExpr = Param->getUninstantiatedDefaultArg(); 3277 3278 // Instantiate the expression. 3279 MultiLevelTemplateArgumentList ArgList 3280 = getTemplateInstantiationArgs(FD, 0, /*RelativeToPrimary=*/true); 3281 3282 InstantiatingTemplate Inst(*this, CallLoc, Param, 3283 ArgList.getInnermost().getFlatArgumentList(), 3284 ArgList.getInnermost().flat_size()); 3285 3286 OwningExprResult Result = SubstExpr(UninstExpr, ArgList); 3287 if (Result.isInvalid()) 3288 return ExprError(); 3289 3290 // Check the expression as an initializer for the parameter. 3291 InitializedEntity Entity 3292 = InitializedEntity::InitializeParameter(Param); 3293 InitializationKind Kind 3294 = InitializationKind::CreateCopy(Param->getLocation(), 3295 /*FIXME:EqualLoc*/UninstExpr->getSourceRange().getBegin()); 3296 Expr *ResultE = Result.takeAs<Expr>(); 3297 3298 InitializationSequence InitSeq(*this, Entity, Kind, &ResultE, 1); 3299 Result = InitSeq.Perform(*this, Entity, Kind, 3300 MultiExprArg(*this, (void**)&ResultE, 1)); 3301 if (Result.isInvalid()) 3302 return ExprError(); 3303 3304 // Build the default argument expression. 3305 return Owned(CXXDefaultArgExpr::Create(Context, CallLoc, Param, 3306 Result.takeAs<Expr>())); 3307 } 3308 3309 // If the default expression creates temporaries, we need to 3310 // push them to the current stack of expression temporaries so they'll 3311 // be properly destroyed. 3312 // FIXME: We should really be rebuilding the default argument with new 3313 // bound temporaries; see the comment in PR5810. 3314 for (unsigned i = 0, e = Param->getNumDefaultArgTemporaries(); i != e; ++i) 3315 ExprTemporaries.push_back(Param->getDefaultArgTemporary(i)); 3316 } 3317 3318 // We already type-checked the argument, so we know it works. 3319 return Owned(CXXDefaultArgExpr::Create(Context, CallLoc, Param)); 3320} 3321 3322/// ConvertArgumentsForCall - Converts the arguments specified in 3323/// Args/NumArgs to the parameter types of the function FDecl with 3324/// function prototype Proto. Call is the call expression itself, and 3325/// Fn is the function expression. For a C++ member function, this 3326/// routine does not attempt to convert the object argument. Returns 3327/// true if the call is ill-formed. 3328bool 3329Sema::ConvertArgumentsForCall(CallExpr *Call, Expr *Fn, 3330 FunctionDecl *FDecl, 3331 const FunctionProtoType *Proto, 3332 Expr **Args, unsigned NumArgs, 3333 SourceLocation RParenLoc) { 3334 // C99 6.5.2.2p7 - the arguments are implicitly converted, as if by 3335 // assignment, to the types of the corresponding parameter, ... 3336 unsigned NumArgsInProto = Proto->getNumArgs(); 3337 bool Invalid = false; 3338 3339 // If too few arguments are available (and we don't have default 3340 // arguments for the remaining parameters), don't make the call. 3341 if (NumArgs < NumArgsInProto) { 3342 if (!FDecl || NumArgs < FDecl->getMinRequiredArguments()) 3343 return Diag(RParenLoc, diag::err_typecheck_call_too_few_args) 3344 << Fn->getType()->isBlockPointerType() << Fn->getSourceRange(); 3345 Call->setNumArgs(Context, NumArgsInProto); 3346 } 3347 3348 // If too many are passed and not variadic, error on the extras and drop 3349 // them. 3350 if (NumArgs > NumArgsInProto) { 3351 if (!Proto->isVariadic()) { 3352 Diag(Args[NumArgsInProto]->getLocStart(), 3353 diag::err_typecheck_call_too_many_args) 3354 << Fn->getType()->isBlockPointerType() << Fn->getSourceRange() 3355 << SourceRange(Args[NumArgsInProto]->getLocStart(), 3356 Args[NumArgs-1]->getLocEnd()); 3357 // This deletes the extra arguments. 3358 Call->setNumArgs(Context, NumArgsInProto); 3359 return true; 3360 } 3361 } 3362 llvm::SmallVector<Expr *, 8> AllArgs; 3363 VariadicCallType CallType = 3364 Proto->isVariadic() ? VariadicFunction : VariadicDoesNotApply; 3365 if (Fn->getType()->isBlockPointerType()) 3366 CallType = VariadicBlock; // Block 3367 else if (isa<MemberExpr>(Fn)) 3368 CallType = VariadicMethod; 3369 Invalid = GatherArgumentsForCall(Call->getSourceRange().getBegin(), FDecl, 3370 Proto, 0, Args, NumArgs, AllArgs, CallType); 3371 if (Invalid) 3372 return true; 3373 unsigned TotalNumArgs = AllArgs.size(); 3374 for (unsigned i = 0; i < TotalNumArgs; ++i) 3375 Call->setArg(i, AllArgs[i]); 3376 3377 return false; 3378} 3379 3380bool Sema::GatherArgumentsForCall(SourceLocation CallLoc, 3381 FunctionDecl *FDecl, 3382 const FunctionProtoType *Proto, 3383 unsigned FirstProtoArg, 3384 Expr **Args, unsigned NumArgs, 3385 llvm::SmallVector<Expr *, 8> &AllArgs, 3386 VariadicCallType CallType) { 3387 unsigned NumArgsInProto = Proto->getNumArgs(); 3388 unsigned NumArgsToCheck = NumArgs; 3389 bool Invalid = false; 3390 if (NumArgs != NumArgsInProto) 3391 // Use default arguments for missing arguments 3392 NumArgsToCheck = NumArgsInProto; 3393 unsigned ArgIx = 0; 3394 // Continue to check argument types (even if we have too few/many args). 3395 for (unsigned i = FirstProtoArg; i != NumArgsToCheck; i++) { 3396 QualType ProtoArgType = Proto->getArgType(i); 3397 3398 Expr *Arg; 3399 if (ArgIx < NumArgs) { 3400 Arg = Args[ArgIx++]; 3401 3402 if (RequireCompleteType(Arg->getSourceRange().getBegin(), 3403 ProtoArgType, 3404 PDiag(diag::err_call_incomplete_argument) 3405 << Arg->getSourceRange())) 3406 return true; 3407 3408 // Pass the argument 3409 ParmVarDecl *Param = 0; 3410 if (FDecl && i < FDecl->getNumParams()) 3411 Param = FDecl->getParamDecl(i); 3412 3413 3414 InitializedEntity Entity = 3415 Param? InitializedEntity::InitializeParameter(Param) 3416 : InitializedEntity::InitializeParameter(ProtoArgType); 3417 OwningExprResult ArgE = PerformCopyInitialization(Entity, 3418 SourceLocation(), 3419 Owned(Arg)); 3420 if (ArgE.isInvalid()) 3421 return true; 3422 3423 Arg = ArgE.takeAs<Expr>(); 3424 } else { 3425 ParmVarDecl *Param = FDecl->getParamDecl(i); 3426 3427 OwningExprResult ArgExpr = 3428 BuildCXXDefaultArgExpr(CallLoc, FDecl, Param); 3429 if (ArgExpr.isInvalid()) 3430 return true; 3431 3432 Arg = ArgExpr.takeAs<Expr>(); 3433 } 3434 AllArgs.push_back(Arg); 3435 } 3436 3437 // If this is a variadic call, handle args passed through "...". 3438 if (CallType != VariadicDoesNotApply) { 3439 // Promote the arguments (C99 6.5.2.2p7). 3440 for (unsigned i = ArgIx; i < NumArgs; i++) { 3441 Expr *Arg = Args[i]; 3442 Invalid |= DefaultVariadicArgumentPromotion(Arg, CallType); 3443 AllArgs.push_back(Arg); 3444 } 3445 } 3446 return Invalid; 3447} 3448 3449/// ActOnCallExpr - Handle a call to Fn with the specified array of arguments. 3450/// This provides the location of the left/right parens and a list of comma 3451/// locations. 3452Action::OwningExprResult 3453Sema::ActOnCallExpr(Scope *S, ExprArg fn, SourceLocation LParenLoc, 3454 MultiExprArg args, 3455 SourceLocation *CommaLocs, SourceLocation RParenLoc) { 3456 unsigned NumArgs = args.size(); 3457 3458 // Since this might be a postfix expression, get rid of ParenListExprs. 3459 fn = MaybeConvertParenListExprToParenExpr(S, move(fn)); 3460 3461 Expr *Fn = fn.takeAs<Expr>(); 3462 Expr **Args = reinterpret_cast<Expr**>(args.release()); 3463 assert(Fn && "no function call expression"); 3464 3465 if (getLangOptions().CPlusPlus) { 3466 // If this is a pseudo-destructor expression, build the call immediately. 3467 if (isa<CXXPseudoDestructorExpr>(Fn)) { 3468 if (NumArgs > 0) { 3469 // Pseudo-destructor calls should not have any arguments. 3470 Diag(Fn->getLocStart(), diag::err_pseudo_dtor_call_with_args) 3471 << CodeModificationHint::CreateRemoval( 3472 SourceRange(Args[0]->getLocStart(), 3473 Args[NumArgs-1]->getLocEnd())); 3474 3475 for (unsigned I = 0; I != NumArgs; ++I) 3476 Args[I]->Destroy(Context); 3477 3478 NumArgs = 0; 3479 } 3480 3481 return Owned(new (Context) CallExpr(Context, Fn, 0, 0, Context.VoidTy, 3482 RParenLoc)); 3483 } 3484 3485 // Determine whether this is a dependent call inside a C++ template, 3486 // in which case we won't do any semantic analysis now. 3487 // FIXME: Will need to cache the results of name lookup (including ADL) in 3488 // Fn. 3489 bool Dependent = false; 3490 if (Fn->isTypeDependent()) 3491 Dependent = true; 3492 else if (Expr::hasAnyTypeDependentArguments(Args, NumArgs)) 3493 Dependent = true; 3494 3495 if (Dependent) 3496 return Owned(new (Context) CallExpr(Context, Fn, Args, NumArgs, 3497 Context.DependentTy, RParenLoc)); 3498 3499 // Determine whether this is a call to an object (C++ [over.call.object]). 3500 if (Fn->getType()->isRecordType()) 3501 return Owned(BuildCallToObjectOfClassType(S, Fn, LParenLoc, Args, NumArgs, 3502 CommaLocs, RParenLoc)); 3503 3504 Expr *NakedFn = Fn->IgnoreParens(); 3505 3506 // Determine whether this is a call to an unresolved member function. 3507 if (UnresolvedMemberExpr *MemE = dyn_cast<UnresolvedMemberExpr>(NakedFn)) { 3508 // If lookup was unresolved but not dependent (i.e. didn't find 3509 // an unresolved using declaration), it has to be an overloaded 3510 // function set, which means it must contain either multiple 3511 // declarations (all methods or method templates) or a single 3512 // method template. 3513 assert((MemE->getNumDecls() > 1) || 3514 isa<FunctionTemplateDecl>(*MemE->decls_begin())); 3515 (void)MemE; 3516 3517 return BuildCallToMemberFunction(S, Fn, LParenLoc, Args, NumArgs, 3518 CommaLocs, RParenLoc); 3519 } 3520 3521 // Determine whether this is a call to a member function. 3522 if (MemberExpr *MemExpr = dyn_cast<MemberExpr>(NakedFn)) { 3523 NamedDecl *MemDecl = MemExpr->getMemberDecl(); 3524 if (isa<CXXMethodDecl>(MemDecl)) 3525 return BuildCallToMemberFunction(S, Fn, LParenLoc, Args, NumArgs, 3526 CommaLocs, RParenLoc); 3527 } 3528 3529 // Determine whether this is a call to a pointer-to-member function. 3530 if (BinaryOperator *BO = dyn_cast<BinaryOperator>(NakedFn)) { 3531 if (BO->getOpcode() == BinaryOperator::PtrMemD || 3532 BO->getOpcode() == BinaryOperator::PtrMemI) { 3533 if (const FunctionProtoType *FPT = 3534 dyn_cast<FunctionProtoType>(BO->getType())) { 3535 QualType ResultTy = FPT->getResultType().getNonReferenceType(); 3536 3537 ExprOwningPtr<CXXMemberCallExpr> 3538 TheCall(this, new (Context) CXXMemberCallExpr(Context, BO, Args, 3539 NumArgs, ResultTy, 3540 RParenLoc)); 3541 3542 if (CheckCallReturnType(FPT->getResultType(), 3543 BO->getRHS()->getSourceRange().getBegin(), 3544 TheCall.get(), 0)) 3545 return ExprError(); 3546 3547 if (ConvertArgumentsForCall(&*TheCall, BO, 0, FPT, Args, NumArgs, 3548 RParenLoc)) 3549 return ExprError(); 3550 3551 return Owned(MaybeBindToTemporary(TheCall.release()).release()); 3552 } 3553 return ExprError(Diag(Fn->getLocStart(), 3554 diag::err_typecheck_call_not_function) 3555 << Fn->getType() << Fn->getSourceRange()); 3556 } 3557 } 3558 } 3559 3560 // If we're directly calling a function, get the appropriate declaration. 3561 // Also, in C++, keep track of whether we should perform argument-dependent 3562 // lookup and whether there were any explicitly-specified template arguments. 3563 3564 Expr *NakedFn = Fn->IgnoreParens(); 3565 if (isa<UnresolvedLookupExpr>(NakedFn)) { 3566 UnresolvedLookupExpr *ULE = cast<UnresolvedLookupExpr>(NakedFn); 3567 return BuildOverloadedCallExpr(Fn, ULE, LParenLoc, Args, NumArgs, 3568 CommaLocs, RParenLoc); 3569 } 3570 3571 NamedDecl *NDecl = 0; 3572 if (isa<DeclRefExpr>(NakedFn)) 3573 NDecl = cast<DeclRefExpr>(NakedFn)->getDecl(); 3574 3575 return BuildResolvedCallExpr(Fn, NDecl, LParenLoc, Args, NumArgs, RParenLoc); 3576} 3577 3578/// BuildResolvedCallExpr - Build a call to a resolved expression, 3579/// i.e. an expression not of \p OverloadTy. The expression should 3580/// unary-convert to an expression of function-pointer or 3581/// block-pointer type. 3582/// 3583/// \param NDecl the declaration being called, if available 3584Sema::OwningExprResult 3585Sema::BuildResolvedCallExpr(Expr *Fn, NamedDecl *NDecl, 3586 SourceLocation LParenLoc, 3587 Expr **Args, unsigned NumArgs, 3588 SourceLocation RParenLoc) { 3589 FunctionDecl *FDecl = dyn_cast_or_null<FunctionDecl>(NDecl); 3590 3591 // Promote the function operand. 3592 UsualUnaryConversions(Fn); 3593 3594 // Make the call expr early, before semantic checks. This guarantees cleanup 3595 // of arguments and function on error. 3596 ExprOwningPtr<CallExpr> TheCall(this, new (Context) CallExpr(Context, Fn, 3597 Args, NumArgs, 3598 Context.BoolTy, 3599 RParenLoc)); 3600 3601 const FunctionType *FuncT; 3602 if (!Fn->getType()->isBlockPointerType()) { 3603 // C99 6.5.2.2p1 - "The expression that denotes the called function shall 3604 // have type pointer to function". 3605 const PointerType *PT = Fn->getType()->getAs<PointerType>(); 3606 if (PT == 0) 3607 return ExprError(Diag(LParenLoc, diag::err_typecheck_call_not_function) 3608 << Fn->getType() << Fn->getSourceRange()); 3609 FuncT = PT->getPointeeType()->getAs<FunctionType>(); 3610 } else { // This is a block call. 3611 FuncT = Fn->getType()->getAs<BlockPointerType>()->getPointeeType()-> 3612 getAs<FunctionType>(); 3613 } 3614 if (FuncT == 0) 3615 return ExprError(Diag(LParenLoc, diag::err_typecheck_call_not_function) 3616 << Fn->getType() << Fn->getSourceRange()); 3617 3618 // Check for a valid return type 3619 if (CheckCallReturnType(FuncT->getResultType(), 3620 Fn->getSourceRange().getBegin(), TheCall.get(), 3621 FDecl)) 3622 return ExprError(); 3623 3624 // We know the result type of the call, set it. 3625 TheCall->setType(FuncT->getResultType().getNonReferenceType()); 3626 3627 if (const FunctionProtoType *Proto = dyn_cast<FunctionProtoType>(FuncT)) { 3628 if (ConvertArgumentsForCall(&*TheCall, Fn, FDecl, Proto, Args, NumArgs, 3629 RParenLoc)) 3630 return ExprError(); 3631 } else { 3632 assert(isa<FunctionNoProtoType>(FuncT) && "Unknown FunctionType!"); 3633 3634 if (FDecl) { 3635 // Check if we have too few/too many template arguments, based 3636 // on our knowledge of the function definition. 3637 const FunctionDecl *Def = 0; 3638 if (FDecl->getBody(Def) && NumArgs != Def->param_size()) { 3639 const FunctionProtoType *Proto = 3640 Def->getType()->getAs<FunctionProtoType>(); 3641 if (!Proto || !(Proto->isVariadic() && NumArgs >= Def->param_size())) { 3642 Diag(RParenLoc, diag::warn_call_wrong_number_of_arguments) 3643 << (NumArgs > Def->param_size()) << FDecl << Fn->getSourceRange(); 3644 } 3645 } 3646 } 3647 3648 // Promote the arguments (C99 6.5.2.2p6). 3649 for (unsigned i = 0; i != NumArgs; i++) { 3650 Expr *Arg = Args[i]; 3651 DefaultArgumentPromotion(Arg); 3652 if (RequireCompleteType(Arg->getSourceRange().getBegin(), 3653 Arg->getType(), 3654 PDiag(diag::err_call_incomplete_argument) 3655 << Arg->getSourceRange())) 3656 return ExprError(); 3657 TheCall->setArg(i, Arg); 3658 } 3659 } 3660 3661 if (CXXMethodDecl *Method = dyn_cast_or_null<CXXMethodDecl>(FDecl)) 3662 if (!Method->isStatic()) 3663 return ExprError(Diag(LParenLoc, diag::err_member_call_without_object) 3664 << Fn->getSourceRange()); 3665 3666 // Check for sentinels 3667 if (NDecl) 3668 DiagnoseSentinelCalls(NDecl, LParenLoc, Args, NumArgs); 3669 3670 // Do special checking on direct calls to functions. 3671 if (FDecl) { 3672 if (CheckFunctionCall(FDecl, TheCall.get())) 3673 return ExprError(); 3674 3675 if (unsigned BuiltinID = FDecl->getBuiltinID()) 3676 return CheckBuiltinFunctionCall(BuiltinID, TheCall.take()); 3677 } else if (NDecl) { 3678 if (CheckBlockCall(NDecl, TheCall.get())) 3679 return ExprError(); 3680 } 3681 3682 return MaybeBindToTemporary(TheCall.take()); 3683} 3684 3685Action::OwningExprResult 3686Sema::ActOnCompoundLiteral(SourceLocation LParenLoc, TypeTy *Ty, 3687 SourceLocation RParenLoc, ExprArg InitExpr) { 3688 assert((Ty != 0) && "ActOnCompoundLiteral(): missing type"); 3689 // FIXME: put back this assert when initializers are worked out. 3690 //assert((InitExpr != 0) && "ActOnCompoundLiteral(): missing expression"); 3691 3692 TypeSourceInfo *TInfo; 3693 QualType literalType = GetTypeFromParser(Ty, &TInfo); 3694 if (!TInfo) 3695 TInfo = Context.getTrivialTypeSourceInfo(literalType); 3696 3697 return BuildCompoundLiteralExpr(LParenLoc, TInfo, RParenLoc, move(InitExpr)); 3698} 3699 3700Action::OwningExprResult 3701Sema::BuildCompoundLiteralExpr(SourceLocation LParenLoc, TypeSourceInfo *TInfo, 3702 SourceLocation RParenLoc, ExprArg InitExpr) { 3703 QualType literalType = TInfo->getType(); 3704 Expr *literalExpr = static_cast<Expr*>(InitExpr.get()); 3705 3706 if (literalType->isArrayType()) { 3707 if (literalType->isVariableArrayType()) 3708 return ExprError(Diag(LParenLoc, diag::err_variable_object_no_init) 3709 << SourceRange(LParenLoc, literalExpr->getSourceRange().getEnd())); 3710 } else if (!literalType->isDependentType() && 3711 RequireCompleteType(LParenLoc, literalType, 3712 PDiag(diag::err_typecheck_decl_incomplete_type) 3713 << SourceRange(LParenLoc, 3714 literalExpr->getSourceRange().getEnd()))) 3715 return ExprError(); 3716 3717 InitializedEntity Entity 3718 = InitializedEntity::InitializeTemporary(literalType); 3719 InitializationKind Kind 3720 = InitializationKind::CreateCast(SourceRange(LParenLoc, RParenLoc), 3721 /*IsCStyleCast=*/true); 3722 InitializationSequence InitSeq(*this, Entity, Kind, &literalExpr, 1); 3723 OwningExprResult Result = InitSeq.Perform(*this, Entity, Kind, 3724 MultiExprArg(*this, (void**)&literalExpr, 1), 3725 &literalType); 3726 if (Result.isInvalid()) 3727 return ExprError(); 3728 InitExpr.release(); 3729 literalExpr = static_cast<Expr*>(Result.get()); 3730 3731 bool isFileScope = getCurFunctionOrMethodDecl() == 0; 3732 if (isFileScope) { // 6.5.2.5p3 3733 if (CheckForConstantInitializer(literalExpr, literalType)) 3734 return ExprError(); 3735 } 3736 3737 Result.release(); 3738 3739 return Owned(new (Context) CompoundLiteralExpr(LParenLoc, TInfo, literalType, 3740 literalExpr, isFileScope)); 3741} 3742 3743Action::OwningExprResult 3744Sema::ActOnInitList(SourceLocation LBraceLoc, MultiExprArg initlist, 3745 SourceLocation RBraceLoc) { 3746 unsigned NumInit = initlist.size(); 3747 Expr **InitList = reinterpret_cast<Expr**>(initlist.release()); 3748 3749 // Semantic analysis for initializers is done by ActOnDeclarator() and 3750 // CheckInitializer() - it requires knowledge of the object being intialized. 3751 3752 InitListExpr *E = new (Context) InitListExpr(LBraceLoc, InitList, NumInit, 3753 RBraceLoc); 3754 E->setType(Context.VoidTy); // FIXME: just a place holder for now. 3755 return Owned(E); 3756} 3757 3758static CastExpr::CastKind getScalarCastKind(ASTContext &Context, 3759 QualType SrcTy, QualType DestTy) { 3760 if (Context.hasSameUnqualifiedType(SrcTy, DestTy)) 3761 return CastExpr::CK_NoOp; 3762 3763 if (SrcTy->hasPointerRepresentation()) { 3764 if (DestTy->hasPointerRepresentation()) 3765 return DestTy->isObjCObjectPointerType() ? 3766 CastExpr::CK_AnyPointerToObjCPointerCast : 3767 CastExpr::CK_BitCast; 3768 if (DestTy->isIntegerType()) 3769 return CastExpr::CK_PointerToIntegral; 3770 } 3771 3772 if (SrcTy->isIntegerType()) { 3773 if (DestTy->isIntegerType()) 3774 return CastExpr::CK_IntegralCast; 3775 if (DestTy->hasPointerRepresentation()) 3776 return CastExpr::CK_IntegralToPointer; 3777 if (DestTy->isRealFloatingType()) 3778 return CastExpr::CK_IntegralToFloating; 3779 } 3780 3781 if (SrcTy->isRealFloatingType()) { 3782 if (DestTy->isRealFloatingType()) 3783 return CastExpr::CK_FloatingCast; 3784 if (DestTy->isIntegerType()) 3785 return CastExpr::CK_FloatingToIntegral; 3786 } 3787 3788 // FIXME: Assert here. 3789 // assert(false && "Unhandled cast combination!"); 3790 return CastExpr::CK_Unknown; 3791} 3792 3793/// CheckCastTypes - Check type constraints for casting between types. 3794bool Sema::CheckCastTypes(SourceRange TyR, QualType castType, Expr *&castExpr, 3795 CastExpr::CastKind& Kind, 3796 CXXMethodDecl *& ConversionDecl, 3797 bool FunctionalStyle) { 3798 if (getLangOptions().CPlusPlus) 3799 return CXXCheckCStyleCast(TyR, castType, castExpr, Kind, FunctionalStyle, 3800 ConversionDecl); 3801 3802 DefaultFunctionArrayLvalueConversion(castExpr); 3803 3804 // C99 6.5.4p2: the cast type needs to be void or scalar and the expression 3805 // type needs to be scalar. 3806 if (castType->isVoidType()) { 3807 // Cast to void allows any expr type. 3808 Kind = CastExpr::CK_ToVoid; 3809 return false; 3810 } 3811 3812 if (!castType->isScalarType() && !castType->isVectorType()) { 3813 if (Context.hasSameUnqualifiedType(castType, castExpr->getType()) && 3814 (castType->isStructureType() || castType->isUnionType())) { 3815 // GCC struct/union extension: allow cast to self. 3816 // FIXME: Check that the cast destination type is complete. 3817 Diag(TyR.getBegin(), diag::ext_typecheck_cast_nonscalar) 3818 << castType << castExpr->getSourceRange(); 3819 Kind = CastExpr::CK_NoOp; 3820 return false; 3821 } 3822 3823 if (castType->isUnionType()) { 3824 // GCC cast to union extension 3825 RecordDecl *RD = castType->getAs<RecordType>()->getDecl(); 3826 RecordDecl::field_iterator Field, FieldEnd; 3827 for (Field = RD->field_begin(), FieldEnd = RD->field_end(); 3828 Field != FieldEnd; ++Field) { 3829 if (Context.hasSameUnqualifiedType(Field->getType(), 3830 castExpr->getType())) { 3831 Diag(TyR.getBegin(), diag::ext_typecheck_cast_to_union) 3832 << castExpr->getSourceRange(); 3833 break; 3834 } 3835 } 3836 if (Field == FieldEnd) 3837 return Diag(TyR.getBegin(), diag::err_typecheck_cast_to_union_no_type) 3838 << castExpr->getType() << castExpr->getSourceRange(); 3839 Kind = CastExpr::CK_ToUnion; 3840 return false; 3841 } 3842 3843 // Reject any other conversions to non-scalar types. 3844 return Diag(TyR.getBegin(), diag::err_typecheck_cond_expect_scalar) 3845 << castType << castExpr->getSourceRange(); 3846 } 3847 3848 if (!castExpr->getType()->isScalarType() && 3849 !castExpr->getType()->isVectorType()) { 3850 return Diag(castExpr->getLocStart(), 3851 diag::err_typecheck_expect_scalar_operand) 3852 << castExpr->getType() << castExpr->getSourceRange(); 3853 } 3854 3855 if (castType->isExtVectorType()) 3856 return CheckExtVectorCast(TyR, castType, castExpr, Kind); 3857 3858 if (castType->isVectorType()) 3859 return CheckVectorCast(TyR, castType, castExpr->getType(), Kind); 3860 if (castExpr->getType()->isVectorType()) 3861 return CheckVectorCast(TyR, castExpr->getType(), castType, Kind); 3862 3863 if (getLangOptions().ObjC1 && isa<ObjCSuperExpr>(castExpr)) 3864 return Diag(castExpr->getLocStart(), diag::err_illegal_super_cast) << TyR; 3865 3866 if (isa<ObjCSelectorExpr>(castExpr)) 3867 return Diag(castExpr->getLocStart(), diag::err_cast_selector_expr); 3868 3869 if (!castType->isArithmeticType()) { 3870 QualType castExprType = castExpr->getType(); 3871 if (!castExprType->isIntegralType() && castExprType->isArithmeticType()) 3872 return Diag(castExpr->getLocStart(), 3873 diag::err_cast_pointer_from_non_pointer_int) 3874 << castExprType << castExpr->getSourceRange(); 3875 } else if (!castExpr->getType()->isArithmeticType()) { 3876 if (!castType->isIntegralType() && castType->isArithmeticType()) 3877 return Diag(castExpr->getLocStart(), 3878 diag::err_cast_pointer_to_non_pointer_int) 3879 << castType << castExpr->getSourceRange(); 3880 } 3881 3882 Kind = getScalarCastKind(Context, castExpr->getType(), castType); 3883 return false; 3884} 3885 3886bool Sema::CheckVectorCast(SourceRange R, QualType VectorTy, QualType Ty, 3887 CastExpr::CastKind &Kind) { 3888 assert(VectorTy->isVectorType() && "Not a vector type!"); 3889 3890 if (Ty->isVectorType() || Ty->isIntegerType()) { 3891 if (Context.getTypeSize(VectorTy) != Context.getTypeSize(Ty)) 3892 return Diag(R.getBegin(), 3893 Ty->isVectorType() ? 3894 diag::err_invalid_conversion_between_vectors : 3895 diag::err_invalid_conversion_between_vector_and_integer) 3896 << VectorTy << Ty << R; 3897 } else 3898 return Diag(R.getBegin(), 3899 diag::err_invalid_conversion_between_vector_and_scalar) 3900 << VectorTy << Ty << R; 3901 3902 Kind = CastExpr::CK_BitCast; 3903 return false; 3904} 3905 3906bool Sema::CheckExtVectorCast(SourceRange R, QualType DestTy, Expr *&CastExpr, 3907 CastExpr::CastKind &Kind) { 3908 assert(DestTy->isExtVectorType() && "Not an extended vector type!"); 3909 3910 QualType SrcTy = CastExpr->getType(); 3911 3912 // If SrcTy is a VectorType, the total size must match to explicitly cast to 3913 // an ExtVectorType. 3914 if (SrcTy->isVectorType()) { 3915 if (Context.getTypeSize(DestTy) != Context.getTypeSize(SrcTy)) 3916 return Diag(R.getBegin(),diag::err_invalid_conversion_between_ext_vectors) 3917 << DestTy << SrcTy << R; 3918 Kind = CastExpr::CK_BitCast; 3919 return false; 3920 } 3921 3922 // All non-pointer scalars can be cast to ExtVector type. The appropriate 3923 // conversion will take place first from scalar to elt type, and then 3924 // splat from elt type to vector. 3925 if (SrcTy->isPointerType()) 3926 return Diag(R.getBegin(), 3927 diag::err_invalid_conversion_between_vector_and_scalar) 3928 << DestTy << SrcTy << R; 3929 3930 QualType DestElemTy = DestTy->getAs<ExtVectorType>()->getElementType(); 3931 ImpCastExprToType(CastExpr, DestElemTy, 3932 getScalarCastKind(Context, SrcTy, DestElemTy)); 3933 3934 Kind = CastExpr::CK_VectorSplat; 3935 return false; 3936} 3937 3938Action::OwningExprResult 3939Sema::ActOnCastExpr(Scope *S, SourceLocation LParenLoc, TypeTy *Ty, 3940 SourceLocation RParenLoc, ExprArg Op) { 3941 assert((Ty != 0) && (Op.get() != 0) && 3942 "ActOnCastExpr(): missing type or expr"); 3943 3944 TypeSourceInfo *castTInfo; 3945 QualType castType = GetTypeFromParser(Ty, &castTInfo); 3946 if (!castTInfo) 3947 castTInfo = Context.getTrivialTypeSourceInfo(castType); 3948 3949 // If the Expr being casted is a ParenListExpr, handle it specially. 3950 Expr *castExpr = (Expr *)Op.get(); 3951 if (isa<ParenListExpr>(castExpr)) 3952 return ActOnCastOfParenListExpr(S, LParenLoc, RParenLoc, move(Op), 3953 castTInfo); 3954 3955 return BuildCStyleCastExpr(LParenLoc, castTInfo, RParenLoc, move(Op)); 3956} 3957 3958Action::OwningExprResult 3959Sema::BuildCStyleCastExpr(SourceLocation LParenLoc, TypeSourceInfo *Ty, 3960 SourceLocation RParenLoc, ExprArg Op) { 3961 Expr *castExpr = static_cast<Expr*>(Op.get()); 3962 3963 CXXMethodDecl *Method = 0; 3964 CastExpr::CastKind Kind = CastExpr::CK_Unknown; 3965 if (CheckCastTypes(SourceRange(LParenLoc, RParenLoc), Ty->getType(), castExpr, 3966 Kind, Method)) 3967 return ExprError(); 3968 3969 if (Method) { 3970 // FIXME: preserve type source info here 3971 OwningExprResult CastArg = BuildCXXCastArgument(LParenLoc, Ty->getType(), 3972 Kind, Method, move(Op)); 3973 3974 if (CastArg.isInvalid()) 3975 return ExprError(); 3976 3977 castExpr = CastArg.takeAs<Expr>(); 3978 } else { 3979 Op.release(); 3980 } 3981 3982 return Owned(new (Context) CStyleCastExpr(Ty->getType().getNonReferenceType(), 3983 Kind, castExpr, Ty, 3984 LParenLoc, RParenLoc)); 3985} 3986 3987/// This is not an AltiVec-style cast, so turn the ParenListExpr into a sequence 3988/// of comma binary operators. 3989Action::OwningExprResult 3990Sema::MaybeConvertParenListExprToParenExpr(Scope *S, ExprArg EA) { 3991 Expr *expr = EA.takeAs<Expr>(); 3992 ParenListExpr *E = dyn_cast<ParenListExpr>(expr); 3993 if (!E) 3994 return Owned(expr); 3995 3996 OwningExprResult Result(*this, E->getExpr(0)); 3997 3998 for (unsigned i = 1, e = E->getNumExprs(); i != e && !Result.isInvalid(); ++i) 3999 Result = ActOnBinOp(S, E->getExprLoc(), tok::comma, move(Result), 4000 Owned(E->getExpr(i))); 4001 4002 return ActOnParenExpr(E->getLParenLoc(), E->getRParenLoc(), move(Result)); 4003} 4004 4005Action::OwningExprResult 4006Sema::ActOnCastOfParenListExpr(Scope *S, SourceLocation LParenLoc, 4007 SourceLocation RParenLoc, ExprArg Op, 4008 TypeSourceInfo *TInfo) { 4009 ParenListExpr *PE = (ParenListExpr *)Op.get(); 4010 QualType Ty = TInfo->getType(); 4011 4012 // If this is an altivec initializer, '(' type ')' '(' init, ..., init ')' 4013 // then handle it as such. 4014 if (getLangOptions().AltiVec && Ty->isVectorType()) { 4015 if (PE->getNumExprs() == 0) { 4016 Diag(PE->getExprLoc(), diag::err_altivec_empty_initializer); 4017 return ExprError(); 4018 } 4019 4020 llvm::SmallVector<Expr *, 8> initExprs; 4021 for (unsigned i = 0, e = PE->getNumExprs(); i != e; ++i) 4022 initExprs.push_back(PE->getExpr(i)); 4023 4024 // FIXME: This means that pretty-printing the final AST will produce curly 4025 // braces instead of the original commas. 4026 Op.release(); 4027 InitListExpr *E = new (Context) InitListExpr(LParenLoc, &initExprs[0], 4028 initExprs.size(), RParenLoc); 4029 E->setType(Ty); 4030 return BuildCompoundLiteralExpr(LParenLoc, TInfo, RParenLoc, Owned(E)); 4031 } else { 4032 // This is not an AltiVec-style cast, so turn the ParenListExpr into a 4033 // sequence of BinOp comma operators. 4034 Op = MaybeConvertParenListExprToParenExpr(S, move(Op)); 4035 return BuildCStyleCastExpr(LParenLoc, TInfo, RParenLoc, move(Op)); 4036 } 4037} 4038 4039Action::OwningExprResult Sema::ActOnParenOrParenListExpr(SourceLocation L, 4040 SourceLocation R, 4041 MultiExprArg Val, 4042 TypeTy *TypeOfCast) { 4043 unsigned nexprs = Val.size(); 4044 Expr **exprs = reinterpret_cast<Expr**>(Val.release()); 4045 assert((exprs != 0) && "ActOnParenOrParenListExpr() missing expr list"); 4046 Expr *expr; 4047 if (nexprs == 1 && TypeOfCast && !TypeIsVectorType(TypeOfCast)) 4048 expr = new (Context) ParenExpr(L, R, exprs[0]); 4049 else 4050 expr = new (Context) ParenListExpr(Context, L, exprs, nexprs, R); 4051 return Owned(expr); 4052} 4053 4054/// Note that lhs is not null here, even if this is the gnu "x ?: y" extension. 4055/// In that case, lhs = cond. 4056/// C99 6.5.15 4057QualType Sema::CheckConditionalOperands(Expr *&Cond, Expr *&LHS, Expr *&RHS, 4058 SourceLocation QuestionLoc) { 4059 // C++ is sufficiently different to merit its own checker. 4060 if (getLangOptions().CPlusPlus) 4061 return CXXCheckConditionalOperands(Cond, LHS, RHS, QuestionLoc); 4062 4063 CheckSignCompare(LHS, RHS, QuestionLoc, diag::warn_mixed_sign_conditional); 4064 4065 UsualUnaryConversions(Cond); 4066 UsualUnaryConversions(LHS); 4067 UsualUnaryConversions(RHS); 4068 QualType CondTy = Cond->getType(); 4069 QualType LHSTy = LHS->getType(); 4070 QualType RHSTy = RHS->getType(); 4071 4072 // first, check the condition. 4073 if (!CondTy->isScalarType()) { // C99 6.5.15p2 4074 Diag(Cond->getLocStart(), diag::err_typecheck_cond_expect_scalar) 4075 << CondTy; 4076 return QualType(); 4077 } 4078 4079 // Now check the two expressions. 4080 if (LHSTy->isVectorType() || RHSTy->isVectorType()) 4081 return CheckVectorOperands(QuestionLoc, LHS, RHS); 4082 4083 // If both operands have arithmetic type, do the usual arithmetic conversions 4084 // to find a common type: C99 6.5.15p3,5. 4085 if (LHSTy->isArithmeticType() && RHSTy->isArithmeticType()) { 4086 UsualArithmeticConversions(LHS, RHS); 4087 return LHS->getType(); 4088 } 4089 4090 // If both operands are the same structure or union type, the result is that 4091 // type. 4092 if (const RecordType *LHSRT = LHSTy->getAs<RecordType>()) { // C99 6.5.15p3 4093 if (const RecordType *RHSRT = RHSTy->getAs<RecordType>()) 4094 if (LHSRT->getDecl() == RHSRT->getDecl()) 4095 // "If both the operands have structure or union type, the result has 4096 // that type." This implies that CV qualifiers are dropped. 4097 return LHSTy.getUnqualifiedType(); 4098 // FIXME: Type of conditional expression must be complete in C mode. 4099 } 4100 4101 // C99 6.5.15p5: "If both operands have void type, the result has void type." 4102 // The following || allows only one side to be void (a GCC-ism). 4103 if (LHSTy->isVoidType() || RHSTy->isVoidType()) { 4104 if (!LHSTy->isVoidType()) 4105 Diag(RHS->getLocStart(), diag::ext_typecheck_cond_one_void) 4106 << RHS->getSourceRange(); 4107 if (!RHSTy->isVoidType()) 4108 Diag(LHS->getLocStart(), diag::ext_typecheck_cond_one_void) 4109 << LHS->getSourceRange(); 4110 ImpCastExprToType(LHS, Context.VoidTy, CastExpr::CK_ToVoid); 4111 ImpCastExprToType(RHS, Context.VoidTy, CastExpr::CK_ToVoid); 4112 return Context.VoidTy; 4113 } 4114 // C99 6.5.15p6 - "if one operand is a null pointer constant, the result has 4115 // the type of the other operand." 4116 if ((LHSTy->isAnyPointerType() || LHSTy->isBlockPointerType()) && 4117 RHS->isNullPointerConstant(Context, Expr::NPC_ValueDependentIsNull)) { 4118 // promote the null to a pointer. 4119 ImpCastExprToType(RHS, LHSTy, CastExpr::CK_Unknown); 4120 return LHSTy; 4121 } 4122 if ((RHSTy->isAnyPointerType() || RHSTy->isBlockPointerType()) && 4123 LHS->isNullPointerConstant(Context, Expr::NPC_ValueDependentIsNull)) { 4124 ImpCastExprToType(LHS, RHSTy, CastExpr::CK_Unknown); 4125 return RHSTy; 4126 } 4127 4128 // All objective-c pointer type analysis is done here. 4129 QualType compositeType = FindCompositeObjCPointerType(LHS, RHS, 4130 QuestionLoc); 4131 if (!compositeType.isNull()) 4132 return compositeType; 4133 4134 4135 // Handle block pointer types. 4136 if (LHSTy->isBlockPointerType() || RHSTy->isBlockPointerType()) { 4137 if (!LHSTy->isBlockPointerType() || !RHSTy->isBlockPointerType()) { 4138 if (LHSTy->isVoidPointerType() || RHSTy->isVoidPointerType()) { 4139 QualType destType = Context.getPointerType(Context.VoidTy); 4140 ImpCastExprToType(LHS, destType, CastExpr::CK_BitCast); 4141 ImpCastExprToType(RHS, destType, CastExpr::CK_BitCast); 4142 return destType; 4143 } 4144 Diag(QuestionLoc, diag::err_typecheck_cond_incompatible_operands) 4145 << LHSTy << RHSTy << LHS->getSourceRange() << RHS->getSourceRange(); 4146 return QualType(); 4147 } 4148 // We have 2 block pointer types. 4149 if (Context.getCanonicalType(LHSTy) == Context.getCanonicalType(RHSTy)) { 4150 // Two identical block pointer types are always compatible. 4151 return LHSTy; 4152 } 4153 // The block pointer types aren't identical, continue checking. 4154 QualType lhptee = LHSTy->getAs<BlockPointerType>()->getPointeeType(); 4155 QualType rhptee = RHSTy->getAs<BlockPointerType>()->getPointeeType(); 4156 4157 if (!Context.typesAreCompatible(lhptee.getUnqualifiedType(), 4158 rhptee.getUnqualifiedType())) { 4159 Diag(QuestionLoc, diag::warn_typecheck_cond_incompatible_pointers) 4160 << LHSTy << RHSTy << LHS->getSourceRange() << RHS->getSourceRange(); 4161 // In this situation, we assume void* type. No especially good 4162 // reason, but this is what gcc does, and we do have to pick 4163 // to get a consistent AST. 4164 QualType incompatTy = Context.getPointerType(Context.VoidTy); 4165 ImpCastExprToType(LHS, incompatTy, CastExpr::CK_BitCast); 4166 ImpCastExprToType(RHS, incompatTy, CastExpr::CK_BitCast); 4167 return incompatTy; 4168 } 4169 // The block pointer types are compatible. 4170 ImpCastExprToType(LHS, LHSTy, CastExpr::CK_BitCast); 4171 ImpCastExprToType(RHS, LHSTy, CastExpr::CK_BitCast); 4172 return LHSTy; 4173 } 4174 4175 // Check constraints for C object pointers types (C99 6.5.15p3,6). 4176 if (LHSTy->isPointerType() && RHSTy->isPointerType()) { 4177 // get the "pointed to" types 4178 QualType lhptee = LHSTy->getAs<PointerType>()->getPointeeType(); 4179 QualType rhptee = RHSTy->getAs<PointerType>()->getPointeeType(); 4180 4181 // ignore qualifiers on void (C99 6.5.15p3, clause 6) 4182 if (lhptee->isVoidType() && rhptee->isIncompleteOrObjectType()) { 4183 // Figure out necessary qualifiers (C99 6.5.15p6) 4184 QualType destPointee 4185 = Context.getQualifiedType(lhptee, rhptee.getQualifiers()); 4186 QualType destType = Context.getPointerType(destPointee); 4187 // Add qualifiers if necessary. 4188 ImpCastExprToType(LHS, destType, CastExpr::CK_NoOp); 4189 // Promote to void*. 4190 ImpCastExprToType(RHS, destType, CastExpr::CK_BitCast); 4191 return destType; 4192 } 4193 if (rhptee->isVoidType() && lhptee->isIncompleteOrObjectType()) { 4194 QualType destPointee 4195 = Context.getQualifiedType(rhptee, lhptee.getQualifiers()); 4196 QualType destType = Context.getPointerType(destPointee); 4197 // Add qualifiers if necessary. 4198 ImpCastExprToType(RHS, destType, CastExpr::CK_NoOp); 4199 // Promote to void*. 4200 ImpCastExprToType(LHS, destType, CastExpr::CK_BitCast); 4201 return destType; 4202 } 4203 4204 if (Context.getCanonicalType(LHSTy) == Context.getCanonicalType(RHSTy)) { 4205 // Two identical pointer types are always compatible. 4206 return LHSTy; 4207 } 4208 if (!Context.typesAreCompatible(lhptee.getUnqualifiedType(), 4209 rhptee.getUnqualifiedType())) { 4210 Diag(QuestionLoc, diag::warn_typecheck_cond_incompatible_pointers) 4211 << LHSTy << RHSTy << LHS->getSourceRange() << RHS->getSourceRange(); 4212 // In this situation, we assume void* type. No especially good 4213 // reason, but this is what gcc does, and we do have to pick 4214 // to get a consistent AST. 4215 QualType incompatTy = Context.getPointerType(Context.VoidTy); 4216 ImpCastExprToType(LHS, incompatTy, CastExpr::CK_BitCast); 4217 ImpCastExprToType(RHS, incompatTy, CastExpr::CK_BitCast); 4218 return incompatTy; 4219 } 4220 // The pointer types are compatible. 4221 // C99 6.5.15p6: If both operands are pointers to compatible types *or* to 4222 // differently qualified versions of compatible types, the result type is 4223 // a pointer to an appropriately qualified version of the *composite* 4224 // type. 4225 // FIXME: Need to calculate the composite type. 4226 // FIXME: Need to add qualifiers 4227 ImpCastExprToType(LHS, LHSTy, CastExpr::CK_BitCast); 4228 ImpCastExprToType(RHS, LHSTy, CastExpr::CK_BitCast); 4229 return LHSTy; 4230 } 4231 4232 // GCC compatibility: soften pointer/integer mismatch. 4233 if (RHSTy->isPointerType() && LHSTy->isIntegerType()) { 4234 Diag(QuestionLoc, diag::warn_typecheck_cond_pointer_integer_mismatch) 4235 << LHSTy << RHSTy << LHS->getSourceRange() << RHS->getSourceRange(); 4236 ImpCastExprToType(LHS, RHSTy, CastExpr::CK_IntegralToPointer); 4237 return RHSTy; 4238 } 4239 if (LHSTy->isPointerType() && RHSTy->isIntegerType()) { 4240 Diag(QuestionLoc, diag::warn_typecheck_cond_pointer_integer_mismatch) 4241 << LHSTy << RHSTy << LHS->getSourceRange() << RHS->getSourceRange(); 4242 ImpCastExprToType(RHS, LHSTy, CastExpr::CK_IntegralToPointer); 4243 return LHSTy; 4244 } 4245 4246 // Otherwise, the operands are not compatible. 4247 Diag(QuestionLoc, diag::err_typecheck_cond_incompatible_operands) 4248 << LHSTy << RHSTy << LHS->getSourceRange() << RHS->getSourceRange(); 4249 return QualType(); 4250} 4251 4252/// FindCompositeObjCPointerType - Helper method to find composite type of 4253/// two objective-c pointer types of the two input expressions. 4254QualType Sema::FindCompositeObjCPointerType(Expr *&LHS, Expr *&RHS, 4255 SourceLocation QuestionLoc) { 4256 QualType LHSTy = LHS->getType(); 4257 QualType RHSTy = RHS->getType(); 4258 4259 // Handle things like Class and struct objc_class*. Here we case the result 4260 // to the pseudo-builtin, because that will be implicitly cast back to the 4261 // redefinition type if an attempt is made to access its fields. 4262 if (LHSTy->isObjCClassType() && 4263 (RHSTy.getDesugaredType() == Context.ObjCClassRedefinitionType)) { 4264 ImpCastExprToType(RHS, LHSTy, CastExpr::CK_BitCast); 4265 return LHSTy; 4266 } 4267 if (RHSTy->isObjCClassType() && 4268 (LHSTy.getDesugaredType() == Context.ObjCClassRedefinitionType)) { 4269 ImpCastExprToType(LHS, RHSTy, CastExpr::CK_BitCast); 4270 return RHSTy; 4271 } 4272 // And the same for struct objc_object* / id 4273 if (LHSTy->isObjCIdType() && 4274 (RHSTy.getDesugaredType() == Context.ObjCIdRedefinitionType)) { 4275 ImpCastExprToType(RHS, LHSTy, CastExpr::CK_BitCast); 4276 return LHSTy; 4277 } 4278 if (RHSTy->isObjCIdType() && 4279 (LHSTy.getDesugaredType() == Context.ObjCIdRedefinitionType)) { 4280 ImpCastExprToType(LHS, RHSTy, CastExpr::CK_BitCast); 4281 return RHSTy; 4282 } 4283 // And the same for struct objc_selector* / SEL 4284 if (Context.isObjCSelType(LHSTy) && 4285 (RHSTy.getDesugaredType() == Context.ObjCSelRedefinitionType)) { 4286 ImpCastExprToType(RHS, LHSTy, CastExpr::CK_BitCast); 4287 return LHSTy; 4288 } 4289 if (Context.isObjCSelType(RHSTy) && 4290 (LHSTy.getDesugaredType() == Context.ObjCSelRedefinitionType)) { 4291 ImpCastExprToType(LHS, RHSTy, CastExpr::CK_BitCast); 4292 return RHSTy; 4293 } 4294 // Check constraints for Objective-C object pointers types. 4295 if (LHSTy->isObjCObjectPointerType() && RHSTy->isObjCObjectPointerType()) { 4296 4297 if (Context.getCanonicalType(LHSTy) == Context.getCanonicalType(RHSTy)) { 4298 // Two identical object pointer types are always compatible. 4299 return LHSTy; 4300 } 4301 const ObjCObjectPointerType *LHSOPT = LHSTy->getAs<ObjCObjectPointerType>(); 4302 const ObjCObjectPointerType *RHSOPT = RHSTy->getAs<ObjCObjectPointerType>(); 4303 QualType compositeType = LHSTy; 4304 4305 // If both operands are interfaces and either operand can be 4306 // assigned to the other, use that type as the composite 4307 // type. This allows 4308 // xxx ? (A*) a : (B*) b 4309 // where B is a subclass of A. 4310 // 4311 // Additionally, as for assignment, if either type is 'id' 4312 // allow silent coercion. Finally, if the types are 4313 // incompatible then make sure to use 'id' as the composite 4314 // type so the result is acceptable for sending messages to. 4315 4316 // FIXME: Consider unifying with 'areComparableObjCPointerTypes'. 4317 // It could return the composite type. 4318 if (Context.canAssignObjCInterfaces(LHSOPT, RHSOPT)) { 4319 compositeType = RHSOPT->isObjCBuiltinType() ? RHSTy : LHSTy; 4320 } else if (Context.canAssignObjCInterfaces(RHSOPT, LHSOPT)) { 4321 compositeType = LHSOPT->isObjCBuiltinType() ? LHSTy : RHSTy; 4322 } else if ((LHSTy->isObjCQualifiedIdType() || 4323 RHSTy->isObjCQualifiedIdType()) && 4324 Context.ObjCQualifiedIdTypesAreCompatible(LHSTy, RHSTy, true)) { 4325 // Need to handle "id<xx>" explicitly. 4326 // GCC allows qualified id and any Objective-C type to devolve to 4327 // id. Currently localizing to here until clear this should be 4328 // part of ObjCQualifiedIdTypesAreCompatible. 4329 compositeType = Context.getObjCIdType(); 4330 } else if (LHSTy->isObjCIdType() || RHSTy->isObjCIdType()) { 4331 compositeType = Context.getObjCIdType(); 4332 } else if (!(compositeType = 4333 Context.areCommonBaseCompatible(LHSOPT, RHSOPT)).isNull()) 4334 ; 4335 else { 4336 Diag(QuestionLoc, diag::ext_typecheck_cond_incompatible_operands) 4337 << LHSTy << RHSTy 4338 << LHS->getSourceRange() << RHS->getSourceRange(); 4339 QualType incompatTy = Context.getObjCIdType(); 4340 ImpCastExprToType(LHS, incompatTy, CastExpr::CK_BitCast); 4341 ImpCastExprToType(RHS, incompatTy, CastExpr::CK_BitCast); 4342 return incompatTy; 4343 } 4344 // The object pointer types are compatible. 4345 ImpCastExprToType(LHS, compositeType, CastExpr::CK_BitCast); 4346 ImpCastExprToType(RHS, compositeType, CastExpr::CK_BitCast); 4347 return compositeType; 4348 } 4349 // Check Objective-C object pointer types and 'void *' 4350 if (LHSTy->isVoidPointerType() && RHSTy->isObjCObjectPointerType()) { 4351 QualType lhptee = LHSTy->getAs<PointerType>()->getPointeeType(); 4352 QualType rhptee = RHSTy->getAs<ObjCObjectPointerType>()->getPointeeType(); 4353 QualType destPointee 4354 = Context.getQualifiedType(lhptee, rhptee.getQualifiers()); 4355 QualType destType = Context.getPointerType(destPointee); 4356 // Add qualifiers if necessary. 4357 ImpCastExprToType(LHS, destType, CastExpr::CK_NoOp); 4358 // Promote to void*. 4359 ImpCastExprToType(RHS, destType, CastExpr::CK_BitCast); 4360 return destType; 4361 } 4362 if (LHSTy->isObjCObjectPointerType() && RHSTy->isVoidPointerType()) { 4363 QualType lhptee = LHSTy->getAs<ObjCObjectPointerType>()->getPointeeType(); 4364 QualType rhptee = RHSTy->getAs<PointerType>()->getPointeeType(); 4365 QualType destPointee 4366 = Context.getQualifiedType(rhptee, lhptee.getQualifiers()); 4367 QualType destType = Context.getPointerType(destPointee); 4368 // Add qualifiers if necessary. 4369 ImpCastExprToType(RHS, destType, CastExpr::CK_NoOp); 4370 // Promote to void*. 4371 ImpCastExprToType(LHS, destType, CastExpr::CK_BitCast); 4372 return destType; 4373 } 4374 return QualType(); 4375} 4376 4377/// ActOnConditionalOp - Parse a ?: operation. Note that 'LHS' may be null 4378/// in the case of a the GNU conditional expr extension. 4379Action::OwningExprResult Sema::ActOnConditionalOp(SourceLocation QuestionLoc, 4380 SourceLocation ColonLoc, 4381 ExprArg Cond, ExprArg LHS, 4382 ExprArg RHS) { 4383 Expr *CondExpr = (Expr *) Cond.get(); 4384 Expr *LHSExpr = (Expr *) LHS.get(), *RHSExpr = (Expr *) RHS.get(); 4385 4386 // If this is the gnu "x ?: y" extension, analyze the types as though the LHS 4387 // was the condition. 4388 bool isLHSNull = LHSExpr == 0; 4389 if (isLHSNull) 4390 LHSExpr = CondExpr; 4391 4392 QualType result = CheckConditionalOperands(CondExpr, LHSExpr, 4393 RHSExpr, QuestionLoc); 4394 if (result.isNull()) 4395 return ExprError(); 4396 4397 Cond.release(); 4398 LHS.release(); 4399 RHS.release(); 4400 return Owned(new (Context) ConditionalOperator(CondExpr, QuestionLoc, 4401 isLHSNull ? 0 : LHSExpr, 4402 ColonLoc, RHSExpr, result)); 4403} 4404 4405// CheckPointerTypesForAssignment - This is a very tricky routine (despite 4406// being closely modeled after the C99 spec:-). The odd characteristic of this 4407// routine is it effectively iqnores the qualifiers on the top level pointee. 4408// This circumvents the usual type rules specified in 6.2.7p1 & 6.7.5.[1-3]. 4409// FIXME: add a couple examples in this comment. 4410Sema::AssignConvertType 4411Sema::CheckPointerTypesForAssignment(QualType lhsType, QualType rhsType) { 4412 QualType lhptee, rhptee; 4413 4414 if ((lhsType->isObjCClassType() && 4415 (rhsType.getDesugaredType() == Context.ObjCClassRedefinitionType)) || 4416 (rhsType->isObjCClassType() && 4417 (lhsType.getDesugaredType() == Context.ObjCClassRedefinitionType))) { 4418 return Compatible; 4419 } 4420 4421 // get the "pointed to" type (ignoring qualifiers at the top level) 4422 lhptee = lhsType->getAs<PointerType>()->getPointeeType(); 4423 rhptee = rhsType->getAs<PointerType>()->getPointeeType(); 4424 4425 // make sure we operate on the canonical type 4426 lhptee = Context.getCanonicalType(lhptee); 4427 rhptee = Context.getCanonicalType(rhptee); 4428 4429 AssignConvertType ConvTy = Compatible; 4430 4431 // C99 6.5.16.1p1: This following citation is common to constraints 4432 // 3 & 4 (below). ...and the type *pointed to* by the left has all the 4433 // qualifiers of the type *pointed to* by the right; 4434 // FIXME: Handle ExtQualType 4435 if (!lhptee.isAtLeastAsQualifiedAs(rhptee)) 4436 ConvTy = CompatiblePointerDiscardsQualifiers; 4437 4438 // C99 6.5.16.1p1 (constraint 4): If one operand is a pointer to an object or 4439 // incomplete type and the other is a pointer to a qualified or unqualified 4440 // version of void... 4441 if (lhptee->isVoidType()) { 4442 if (rhptee->isIncompleteOrObjectType()) 4443 return ConvTy; 4444 4445 // As an extension, we allow cast to/from void* to function pointer. 4446 assert(rhptee->isFunctionType()); 4447 return FunctionVoidPointer; 4448 } 4449 4450 if (rhptee->isVoidType()) { 4451 if (lhptee->isIncompleteOrObjectType()) 4452 return ConvTy; 4453 4454 // As an extension, we allow cast to/from void* to function pointer. 4455 assert(lhptee->isFunctionType()); 4456 return FunctionVoidPointer; 4457 } 4458 // C99 6.5.16.1p1 (constraint 3): both operands are pointers to qualified or 4459 // unqualified versions of compatible types, ... 4460 lhptee = lhptee.getUnqualifiedType(); 4461 rhptee = rhptee.getUnqualifiedType(); 4462 if (!Context.typesAreCompatible(lhptee, rhptee)) { 4463 // Check if the pointee types are compatible ignoring the sign. 4464 // We explicitly check for char so that we catch "char" vs 4465 // "unsigned char" on systems where "char" is unsigned. 4466 if (lhptee->isCharType()) 4467 lhptee = Context.UnsignedCharTy; 4468 else if (lhptee->isSignedIntegerType()) 4469 lhptee = Context.getCorrespondingUnsignedType(lhptee); 4470 4471 if (rhptee->isCharType()) 4472 rhptee = Context.UnsignedCharTy; 4473 else if (rhptee->isSignedIntegerType()) 4474 rhptee = Context.getCorrespondingUnsignedType(rhptee); 4475 4476 if (lhptee == rhptee) { 4477 // Types are compatible ignoring the sign. Qualifier incompatibility 4478 // takes priority over sign incompatibility because the sign 4479 // warning can be disabled. 4480 if (ConvTy != Compatible) 4481 return ConvTy; 4482 return IncompatiblePointerSign; 4483 } 4484 4485 // If we are a multi-level pointer, it's possible that our issue is simply 4486 // one of qualification - e.g. char ** -> const char ** is not allowed. If 4487 // the eventual target type is the same and the pointers have the same 4488 // level of indirection, this must be the issue. 4489 if (lhptee->isPointerType() && rhptee->isPointerType()) { 4490 do { 4491 lhptee = lhptee->getAs<PointerType>()->getPointeeType(); 4492 rhptee = rhptee->getAs<PointerType>()->getPointeeType(); 4493 4494 lhptee = Context.getCanonicalType(lhptee); 4495 rhptee = Context.getCanonicalType(rhptee); 4496 } while (lhptee->isPointerType() && rhptee->isPointerType()); 4497 4498 if (Context.hasSameUnqualifiedType(lhptee, rhptee)) 4499 return IncompatibleNestedPointerQualifiers; 4500 } 4501 4502 // General pointer incompatibility takes priority over qualifiers. 4503 return IncompatiblePointer; 4504 } 4505 return ConvTy; 4506} 4507 4508/// CheckBlockPointerTypesForAssignment - This routine determines whether two 4509/// block pointer types are compatible or whether a block and normal pointer 4510/// are compatible. It is more restrict than comparing two function pointer 4511// types. 4512Sema::AssignConvertType 4513Sema::CheckBlockPointerTypesForAssignment(QualType lhsType, 4514 QualType rhsType) { 4515 QualType lhptee, rhptee; 4516 4517 // get the "pointed to" type (ignoring qualifiers at the top level) 4518 lhptee = lhsType->getAs<BlockPointerType>()->getPointeeType(); 4519 rhptee = rhsType->getAs<BlockPointerType>()->getPointeeType(); 4520 4521 // make sure we operate on the canonical type 4522 lhptee = Context.getCanonicalType(lhptee); 4523 rhptee = Context.getCanonicalType(rhptee); 4524 4525 AssignConvertType ConvTy = Compatible; 4526 4527 // For blocks we enforce that qualifiers are identical. 4528 if (lhptee.getLocalCVRQualifiers() != rhptee.getLocalCVRQualifiers()) 4529 ConvTy = CompatiblePointerDiscardsQualifiers; 4530 4531 if (!Context.typesAreCompatible(lhptee, rhptee)) 4532 return IncompatibleBlockPointer; 4533 return ConvTy; 4534} 4535 4536/// CheckObjCPointerTypesForAssignment - Compares two objective-c pointer types 4537/// for assignment compatibility. 4538Sema::AssignConvertType 4539Sema::CheckObjCPointerTypesForAssignment(QualType lhsType, QualType rhsType) { 4540 if (lhsType->isObjCBuiltinType() || rhsType->isObjCBuiltinType()) 4541 return Compatible; 4542 QualType lhptee = 4543 lhsType->getAs<ObjCObjectPointerType>()->getPointeeType(); 4544 QualType rhptee = 4545 rhsType->getAs<ObjCObjectPointerType>()->getPointeeType(); 4546 // make sure we operate on the canonical type 4547 lhptee = Context.getCanonicalType(lhptee); 4548 rhptee = Context.getCanonicalType(rhptee); 4549 if (!lhptee.isAtLeastAsQualifiedAs(rhptee)) 4550 return CompatiblePointerDiscardsQualifiers; 4551 4552 if (Context.typesAreCompatible(lhsType, rhsType)) 4553 return Compatible; 4554 if (lhsType->isObjCQualifiedIdType() || rhsType->isObjCQualifiedIdType()) 4555 return IncompatibleObjCQualifiedId; 4556 return IncompatiblePointer; 4557} 4558 4559/// CheckAssignmentConstraints (C99 6.5.16) - This routine currently 4560/// has code to accommodate several GCC extensions when type checking 4561/// pointers. Here are some objectionable examples that GCC considers warnings: 4562/// 4563/// int a, *pint; 4564/// short *pshort; 4565/// struct foo *pfoo; 4566/// 4567/// pint = pshort; // warning: assignment from incompatible pointer type 4568/// a = pint; // warning: assignment makes integer from pointer without a cast 4569/// pint = a; // warning: assignment makes pointer from integer without a cast 4570/// pint = pfoo; // warning: assignment from incompatible pointer type 4571/// 4572/// As a result, the code for dealing with pointers is more complex than the 4573/// C99 spec dictates. 4574/// 4575Sema::AssignConvertType 4576Sema::CheckAssignmentConstraints(QualType lhsType, QualType rhsType) { 4577 // Get canonical types. We're not formatting these types, just comparing 4578 // them. 4579 lhsType = Context.getCanonicalType(lhsType).getUnqualifiedType(); 4580 rhsType = Context.getCanonicalType(rhsType).getUnqualifiedType(); 4581 4582 if (lhsType == rhsType) 4583 return Compatible; // Common case: fast path an exact match. 4584 4585 if ((lhsType->isObjCClassType() && 4586 (rhsType.getDesugaredType() == Context.ObjCClassRedefinitionType)) || 4587 (rhsType->isObjCClassType() && 4588 (lhsType.getDesugaredType() == Context.ObjCClassRedefinitionType))) { 4589 return Compatible; 4590 } 4591 4592 // If the left-hand side is a reference type, then we are in a 4593 // (rare!) case where we've allowed the use of references in C, 4594 // e.g., as a parameter type in a built-in function. In this case, 4595 // just make sure that the type referenced is compatible with the 4596 // right-hand side type. The caller is responsible for adjusting 4597 // lhsType so that the resulting expression does not have reference 4598 // type. 4599 if (const ReferenceType *lhsTypeRef = lhsType->getAs<ReferenceType>()) { 4600 if (Context.typesAreCompatible(lhsTypeRef->getPointeeType(), rhsType)) 4601 return Compatible; 4602 return Incompatible; 4603 } 4604 // Allow scalar to ExtVector assignments, and assignments of an ExtVector type 4605 // to the same ExtVector type. 4606 if (lhsType->isExtVectorType()) { 4607 if (rhsType->isExtVectorType()) 4608 return lhsType == rhsType ? Compatible : Incompatible; 4609 if (!rhsType->isVectorType() && rhsType->isArithmeticType()) 4610 return Compatible; 4611 } 4612 4613 if (lhsType->isVectorType() || rhsType->isVectorType()) { 4614 // If we are allowing lax vector conversions, and LHS and RHS are both 4615 // vectors, the total size only needs to be the same. This is a bitcast; 4616 // no bits are changed but the result type is different. 4617 if (getLangOptions().LaxVectorConversions && 4618 lhsType->isVectorType() && rhsType->isVectorType()) { 4619 if (Context.getTypeSize(lhsType) == Context.getTypeSize(rhsType)) 4620 return IncompatibleVectors; 4621 } 4622 return Incompatible; 4623 } 4624 4625 if (lhsType->isArithmeticType() && rhsType->isArithmeticType()) 4626 return Compatible; 4627 4628 if (isa<PointerType>(lhsType)) { 4629 if (rhsType->isIntegerType()) 4630 return IntToPointer; 4631 4632 if (isa<PointerType>(rhsType)) 4633 return CheckPointerTypesForAssignment(lhsType, rhsType); 4634 4635 // In general, C pointers are not compatible with ObjC object pointers. 4636 if (isa<ObjCObjectPointerType>(rhsType)) { 4637 if (lhsType->isVoidPointerType()) // an exception to the rule. 4638 return Compatible; 4639 return IncompatiblePointer; 4640 } 4641 if (rhsType->getAs<BlockPointerType>()) { 4642 if (lhsType->getAs<PointerType>()->getPointeeType()->isVoidType()) 4643 return Compatible; 4644 4645 // Treat block pointers as objects. 4646 if (getLangOptions().ObjC1 && lhsType->isObjCIdType()) 4647 return Compatible; 4648 } 4649 return Incompatible; 4650 } 4651 4652 if (isa<BlockPointerType>(lhsType)) { 4653 if (rhsType->isIntegerType()) 4654 return IntToBlockPointer; 4655 4656 // Treat block pointers as objects. 4657 if (getLangOptions().ObjC1 && rhsType->isObjCIdType()) 4658 return Compatible; 4659 4660 if (rhsType->isBlockPointerType()) 4661 return CheckBlockPointerTypesForAssignment(lhsType, rhsType); 4662 4663 if (const PointerType *RHSPT = rhsType->getAs<PointerType>()) { 4664 if (RHSPT->getPointeeType()->isVoidType()) 4665 return Compatible; 4666 } 4667 return Incompatible; 4668 } 4669 4670 if (isa<ObjCObjectPointerType>(lhsType)) { 4671 if (rhsType->isIntegerType()) 4672 return IntToPointer; 4673 4674 // In general, C pointers are not compatible with ObjC object pointers. 4675 if (isa<PointerType>(rhsType)) { 4676 if (rhsType->isVoidPointerType()) // an exception to the rule. 4677 return Compatible; 4678 return IncompatiblePointer; 4679 } 4680 if (rhsType->isObjCObjectPointerType()) { 4681 return CheckObjCPointerTypesForAssignment(lhsType, rhsType); 4682 } 4683 if (const PointerType *RHSPT = rhsType->getAs<PointerType>()) { 4684 if (RHSPT->getPointeeType()->isVoidType()) 4685 return Compatible; 4686 } 4687 // Treat block pointers as objects. 4688 if (rhsType->isBlockPointerType()) 4689 return Compatible; 4690 return Incompatible; 4691 } 4692 if (isa<PointerType>(rhsType)) { 4693 // C99 6.5.16.1p1: the left operand is _Bool and the right is a pointer. 4694 if (lhsType == Context.BoolTy) 4695 return Compatible; 4696 4697 if (lhsType->isIntegerType()) 4698 return PointerToInt; 4699 4700 if (isa<PointerType>(lhsType)) 4701 return CheckPointerTypesForAssignment(lhsType, rhsType); 4702 4703 if (isa<BlockPointerType>(lhsType) && 4704 rhsType->getAs<PointerType>()->getPointeeType()->isVoidType()) 4705 return Compatible; 4706 return Incompatible; 4707 } 4708 if (isa<ObjCObjectPointerType>(rhsType)) { 4709 // C99 6.5.16.1p1: the left operand is _Bool and the right is a pointer. 4710 if (lhsType == Context.BoolTy) 4711 return Compatible; 4712 4713 if (lhsType->isIntegerType()) 4714 return PointerToInt; 4715 4716 // In general, C pointers are not compatible with ObjC object pointers. 4717 if (isa<PointerType>(lhsType)) { 4718 if (lhsType->isVoidPointerType()) // an exception to the rule. 4719 return Compatible; 4720 return IncompatiblePointer; 4721 } 4722 if (isa<BlockPointerType>(lhsType) && 4723 rhsType->getAs<PointerType>()->getPointeeType()->isVoidType()) 4724 return Compatible; 4725 return Incompatible; 4726 } 4727 4728 if (isa<TagType>(lhsType) && isa<TagType>(rhsType)) { 4729 if (Context.typesAreCompatible(lhsType, rhsType)) 4730 return Compatible; 4731 } 4732 return Incompatible; 4733} 4734 4735/// \brief Constructs a transparent union from an expression that is 4736/// used to initialize the transparent union. 4737static void ConstructTransparentUnion(ASTContext &C, Expr *&E, 4738 QualType UnionType, FieldDecl *Field) { 4739 // Build an initializer list that designates the appropriate member 4740 // of the transparent union. 4741 InitListExpr *Initializer = new (C) InitListExpr(SourceLocation(), 4742 &E, 1, 4743 SourceLocation()); 4744 Initializer->setType(UnionType); 4745 Initializer->setInitializedFieldInUnion(Field); 4746 4747 // Build a compound literal constructing a value of the transparent 4748 // union type from this initializer list. 4749 TypeSourceInfo *unionTInfo = C.getTrivialTypeSourceInfo(UnionType); 4750 E = new (C) CompoundLiteralExpr(SourceLocation(), unionTInfo, UnionType, 4751 Initializer, false); 4752} 4753 4754Sema::AssignConvertType 4755Sema::CheckTransparentUnionArgumentConstraints(QualType ArgType, Expr *&rExpr) { 4756 QualType FromType = rExpr->getType(); 4757 4758 // If the ArgType is a Union type, we want to handle a potential 4759 // transparent_union GCC extension. 4760 const RecordType *UT = ArgType->getAsUnionType(); 4761 if (!UT || !UT->getDecl()->hasAttr<TransparentUnionAttr>()) 4762 return Incompatible; 4763 4764 // The field to initialize within the transparent union. 4765 RecordDecl *UD = UT->getDecl(); 4766 FieldDecl *InitField = 0; 4767 // It's compatible if the expression matches any of the fields. 4768 for (RecordDecl::field_iterator it = UD->field_begin(), 4769 itend = UD->field_end(); 4770 it != itend; ++it) { 4771 if (it->getType()->isPointerType()) { 4772 // If the transparent union contains a pointer type, we allow: 4773 // 1) void pointer 4774 // 2) null pointer constant 4775 if (FromType->isPointerType()) 4776 if (FromType->getAs<PointerType>()->getPointeeType()->isVoidType()) { 4777 ImpCastExprToType(rExpr, it->getType(), CastExpr::CK_BitCast); 4778 InitField = *it; 4779 break; 4780 } 4781 4782 if (rExpr->isNullPointerConstant(Context, 4783 Expr::NPC_ValueDependentIsNull)) { 4784 ImpCastExprToType(rExpr, it->getType(), CastExpr::CK_IntegralToPointer); 4785 InitField = *it; 4786 break; 4787 } 4788 } 4789 4790 if (CheckAssignmentConstraints(it->getType(), rExpr->getType()) 4791 == Compatible) { 4792 InitField = *it; 4793 break; 4794 } 4795 } 4796 4797 if (!InitField) 4798 return Incompatible; 4799 4800 ConstructTransparentUnion(Context, rExpr, ArgType, InitField); 4801 return Compatible; 4802} 4803 4804Sema::AssignConvertType 4805Sema::CheckSingleAssignmentConstraints(QualType lhsType, Expr *&rExpr) { 4806 if (getLangOptions().CPlusPlus) { 4807 if (!lhsType->isRecordType()) { 4808 // C++ 5.17p3: If the left operand is not of class type, the 4809 // expression is implicitly converted (C++ 4) to the 4810 // cv-unqualified type of the left operand. 4811 if (PerformImplicitConversion(rExpr, lhsType.getUnqualifiedType(), 4812 AA_Assigning)) 4813 return Incompatible; 4814 return Compatible; 4815 } 4816 4817 // FIXME: Currently, we fall through and treat C++ classes like C 4818 // structures. 4819 } 4820 4821 // C99 6.5.16.1p1: the left operand is a pointer and the right is 4822 // a null pointer constant. 4823 if ((lhsType->isPointerType() || 4824 lhsType->isObjCObjectPointerType() || 4825 lhsType->isBlockPointerType()) 4826 && rExpr->isNullPointerConstant(Context, 4827 Expr::NPC_ValueDependentIsNull)) { 4828 ImpCastExprToType(rExpr, lhsType, CastExpr::CK_Unknown); 4829 return Compatible; 4830 } 4831 4832 // This check seems unnatural, however it is necessary to ensure the proper 4833 // conversion of functions/arrays. If the conversion were done for all 4834 // DeclExpr's (created by ActOnIdExpression), it would mess up the unary 4835 // expressions that surpress this implicit conversion (&, sizeof). 4836 // 4837 // Suppress this for references: C++ 8.5.3p5. 4838 if (!lhsType->isReferenceType()) 4839 DefaultFunctionArrayLvalueConversion(rExpr); 4840 4841 Sema::AssignConvertType result = 4842 CheckAssignmentConstraints(lhsType, rExpr->getType()); 4843 4844 // C99 6.5.16.1p2: The value of the right operand is converted to the 4845 // type of the assignment expression. 4846 // CheckAssignmentConstraints allows the left-hand side to be a reference, 4847 // so that we can use references in built-in functions even in C. 4848 // The getNonReferenceType() call makes sure that the resulting expression 4849 // does not have reference type. 4850 if (result != Incompatible && rExpr->getType() != lhsType) 4851 ImpCastExprToType(rExpr, lhsType.getNonReferenceType(), 4852 CastExpr::CK_Unknown); 4853 return result; 4854} 4855 4856QualType Sema::InvalidOperands(SourceLocation Loc, Expr *&lex, Expr *&rex) { 4857 Diag(Loc, diag::err_typecheck_invalid_operands) 4858 << lex->getType() << rex->getType() 4859 << lex->getSourceRange() << rex->getSourceRange(); 4860 return QualType(); 4861} 4862 4863QualType Sema::CheckVectorOperands(SourceLocation Loc, Expr *&lex, Expr *&rex) { 4864 // For conversion purposes, we ignore any qualifiers. 4865 // For example, "const float" and "float" are equivalent. 4866 QualType lhsType = 4867 Context.getCanonicalType(lex->getType()).getUnqualifiedType(); 4868 QualType rhsType = 4869 Context.getCanonicalType(rex->getType()).getUnqualifiedType(); 4870 4871 // If the vector types are identical, return. 4872 if (lhsType == rhsType) 4873 return lhsType; 4874 4875 // Handle the case of a vector & extvector type of the same size and element 4876 // type. It would be nice if we only had one vector type someday. 4877 if (getLangOptions().LaxVectorConversions) { 4878 // FIXME: Should we warn here? 4879 if (const VectorType *LV = lhsType->getAs<VectorType>()) { 4880 if (const VectorType *RV = rhsType->getAs<VectorType>()) 4881 if (LV->getElementType() == RV->getElementType() && 4882 LV->getNumElements() == RV->getNumElements()) { 4883 return lhsType->isExtVectorType() ? lhsType : rhsType; 4884 } 4885 } 4886 } 4887 4888 // Canonicalize the ExtVector to the LHS, remember if we swapped so we can 4889 // swap back (so that we don't reverse the inputs to a subtract, for instance. 4890 bool swapped = false; 4891 if (rhsType->isExtVectorType()) { 4892 swapped = true; 4893 std::swap(rex, lex); 4894 std::swap(rhsType, lhsType); 4895 } 4896 4897 // Handle the case of an ext vector and scalar. 4898 if (const ExtVectorType *LV = lhsType->getAs<ExtVectorType>()) { 4899 QualType EltTy = LV->getElementType(); 4900 if (EltTy->isIntegralType() && rhsType->isIntegralType()) { 4901 if (Context.getIntegerTypeOrder(EltTy, rhsType) >= 0) { 4902 ImpCastExprToType(rex, lhsType, CastExpr::CK_IntegralCast); 4903 if (swapped) std::swap(rex, lex); 4904 return lhsType; 4905 } 4906 } 4907 if (EltTy->isRealFloatingType() && rhsType->isScalarType() && 4908 rhsType->isRealFloatingType()) { 4909 if (Context.getFloatingTypeOrder(EltTy, rhsType) >= 0) { 4910 ImpCastExprToType(rex, lhsType, CastExpr::CK_FloatingCast); 4911 if (swapped) std::swap(rex, lex); 4912 return lhsType; 4913 } 4914 } 4915 } 4916 4917 // Vectors of different size or scalar and non-ext-vector are errors. 4918 Diag(Loc, diag::err_typecheck_vector_not_convertable) 4919 << lex->getType() << rex->getType() 4920 << lex->getSourceRange() << rex->getSourceRange(); 4921 return QualType(); 4922} 4923 4924QualType Sema::CheckMultiplyDivideOperands( 4925 Expr *&lex, Expr *&rex, SourceLocation Loc, bool isCompAssign, bool isDiv) { 4926 if (lex->getType()->isVectorType() || rex->getType()->isVectorType()) 4927 return CheckVectorOperands(Loc, lex, rex); 4928 4929 QualType compType = UsualArithmeticConversions(lex, rex, isCompAssign); 4930 4931 if (!lex->getType()->isArithmeticType() || 4932 !rex->getType()->isArithmeticType()) 4933 return InvalidOperands(Loc, lex, rex); 4934 4935 // Check for division by zero. 4936 if (isDiv && 4937 rex->isNullPointerConstant(Context, Expr::NPC_ValueDependentIsNotNull)) 4938 DiagRuntimeBehavior(Loc, PDiag(diag::warn_division_by_zero) 4939 << rex->getSourceRange()); 4940 4941 return compType; 4942} 4943 4944QualType Sema::CheckRemainderOperands( 4945 Expr *&lex, Expr *&rex, SourceLocation Loc, bool isCompAssign) { 4946 if (lex->getType()->isVectorType() || rex->getType()->isVectorType()) { 4947 if (lex->getType()->isIntegerType() && rex->getType()->isIntegerType()) 4948 return CheckVectorOperands(Loc, lex, rex); 4949 return InvalidOperands(Loc, lex, rex); 4950 } 4951 4952 QualType compType = UsualArithmeticConversions(lex, rex, isCompAssign); 4953 4954 if (!lex->getType()->isIntegerType() || !rex->getType()->isIntegerType()) 4955 return InvalidOperands(Loc, lex, rex); 4956 4957 // Check for remainder by zero. 4958 if (rex->isNullPointerConstant(Context, Expr::NPC_ValueDependentIsNotNull)) 4959 DiagRuntimeBehavior(Loc, PDiag(diag::warn_remainder_by_zero) 4960 << rex->getSourceRange()); 4961 4962 return compType; 4963} 4964 4965QualType Sema::CheckAdditionOperands( // C99 6.5.6 4966 Expr *&lex, Expr *&rex, SourceLocation Loc, QualType* CompLHSTy) { 4967 if (lex->getType()->isVectorType() || rex->getType()->isVectorType()) { 4968 QualType compType = CheckVectorOperands(Loc, lex, rex); 4969 if (CompLHSTy) *CompLHSTy = compType; 4970 return compType; 4971 } 4972 4973 QualType compType = UsualArithmeticConversions(lex, rex, CompLHSTy); 4974 4975 // handle the common case first (both operands are arithmetic). 4976 if (lex->getType()->isArithmeticType() && 4977 rex->getType()->isArithmeticType()) { 4978 if (CompLHSTy) *CompLHSTy = compType; 4979 return compType; 4980 } 4981 4982 // Put any potential pointer into PExp 4983 Expr* PExp = lex, *IExp = rex; 4984 if (IExp->getType()->isAnyPointerType()) 4985 std::swap(PExp, IExp); 4986 4987 if (PExp->getType()->isAnyPointerType()) { 4988 4989 if (IExp->getType()->isIntegerType()) { 4990 QualType PointeeTy = PExp->getType()->getPointeeType(); 4991 4992 // Check for arithmetic on pointers to incomplete types. 4993 if (PointeeTy->isVoidType()) { 4994 if (getLangOptions().CPlusPlus) { 4995 Diag(Loc, diag::err_typecheck_pointer_arith_void_type) 4996 << lex->getSourceRange() << rex->getSourceRange(); 4997 return QualType(); 4998 } 4999 5000 // GNU extension: arithmetic on pointer to void 5001 Diag(Loc, diag::ext_gnu_void_ptr) 5002 << lex->getSourceRange() << rex->getSourceRange(); 5003 } else if (PointeeTy->isFunctionType()) { 5004 if (getLangOptions().CPlusPlus) { 5005 Diag(Loc, diag::err_typecheck_pointer_arith_function_type) 5006 << lex->getType() << lex->getSourceRange(); 5007 return QualType(); 5008 } 5009 5010 // GNU extension: arithmetic on pointer to function 5011 Diag(Loc, diag::ext_gnu_ptr_func_arith) 5012 << lex->getType() << lex->getSourceRange(); 5013 } else { 5014 // Check if we require a complete type. 5015 if (((PExp->getType()->isPointerType() && 5016 !PExp->getType()->isDependentType()) || 5017 PExp->getType()->isObjCObjectPointerType()) && 5018 RequireCompleteType(Loc, PointeeTy, 5019 PDiag(diag::err_typecheck_arithmetic_incomplete_type) 5020 << PExp->getSourceRange() 5021 << PExp->getType())) 5022 return QualType(); 5023 } 5024 // Diagnose bad cases where we step over interface counts. 5025 if (PointeeTy->isObjCInterfaceType() && LangOpts.ObjCNonFragileABI) { 5026 Diag(Loc, diag::err_arithmetic_nonfragile_interface) 5027 << PointeeTy << PExp->getSourceRange(); 5028 return QualType(); 5029 } 5030 5031 if (CompLHSTy) { 5032 QualType LHSTy = Context.isPromotableBitField(lex); 5033 if (LHSTy.isNull()) { 5034 LHSTy = lex->getType(); 5035 if (LHSTy->isPromotableIntegerType()) 5036 LHSTy = Context.getPromotedIntegerType(LHSTy); 5037 } 5038 *CompLHSTy = LHSTy; 5039 } 5040 return PExp->getType(); 5041 } 5042 } 5043 5044 return InvalidOperands(Loc, lex, rex); 5045} 5046 5047// C99 6.5.6 5048QualType Sema::CheckSubtractionOperands(Expr *&lex, Expr *&rex, 5049 SourceLocation Loc, QualType* CompLHSTy) { 5050 if (lex->getType()->isVectorType() || rex->getType()->isVectorType()) { 5051 QualType compType = CheckVectorOperands(Loc, lex, rex); 5052 if (CompLHSTy) *CompLHSTy = compType; 5053 return compType; 5054 } 5055 5056 QualType compType = UsualArithmeticConversions(lex, rex, CompLHSTy); 5057 5058 // Enforce type constraints: C99 6.5.6p3. 5059 5060 // Handle the common case first (both operands are arithmetic). 5061 if (lex->getType()->isArithmeticType() 5062 && rex->getType()->isArithmeticType()) { 5063 if (CompLHSTy) *CompLHSTy = compType; 5064 return compType; 5065 } 5066 5067 // Either ptr - int or ptr - ptr. 5068 if (lex->getType()->isAnyPointerType()) { 5069 QualType lpointee = lex->getType()->getPointeeType(); 5070 5071 // The LHS must be an completely-defined object type. 5072 5073 bool ComplainAboutVoid = false; 5074 Expr *ComplainAboutFunc = 0; 5075 if (lpointee->isVoidType()) { 5076 if (getLangOptions().CPlusPlus) { 5077 Diag(Loc, diag::err_typecheck_pointer_arith_void_type) 5078 << lex->getSourceRange() << rex->getSourceRange(); 5079 return QualType(); 5080 } 5081 5082 // GNU C extension: arithmetic on pointer to void 5083 ComplainAboutVoid = true; 5084 } else if (lpointee->isFunctionType()) { 5085 if (getLangOptions().CPlusPlus) { 5086 Diag(Loc, diag::err_typecheck_pointer_arith_function_type) 5087 << lex->getType() << lex->getSourceRange(); 5088 return QualType(); 5089 } 5090 5091 // GNU C extension: arithmetic on pointer to function 5092 ComplainAboutFunc = lex; 5093 } else if (!lpointee->isDependentType() && 5094 RequireCompleteType(Loc, lpointee, 5095 PDiag(diag::err_typecheck_sub_ptr_object) 5096 << lex->getSourceRange() 5097 << lex->getType())) 5098 return QualType(); 5099 5100 // Diagnose bad cases where we step over interface counts. 5101 if (lpointee->isObjCInterfaceType() && LangOpts.ObjCNonFragileABI) { 5102 Diag(Loc, diag::err_arithmetic_nonfragile_interface) 5103 << lpointee << lex->getSourceRange(); 5104 return QualType(); 5105 } 5106 5107 // The result type of a pointer-int computation is the pointer type. 5108 if (rex->getType()->isIntegerType()) { 5109 if (ComplainAboutVoid) 5110 Diag(Loc, diag::ext_gnu_void_ptr) 5111 << lex->getSourceRange() << rex->getSourceRange(); 5112 if (ComplainAboutFunc) 5113 Diag(Loc, diag::ext_gnu_ptr_func_arith) 5114 << ComplainAboutFunc->getType() 5115 << ComplainAboutFunc->getSourceRange(); 5116 5117 if (CompLHSTy) *CompLHSTy = lex->getType(); 5118 return lex->getType(); 5119 } 5120 5121 // Handle pointer-pointer subtractions. 5122 if (const PointerType *RHSPTy = rex->getType()->getAs<PointerType>()) { 5123 QualType rpointee = RHSPTy->getPointeeType(); 5124 5125 // RHS must be a completely-type object type. 5126 // Handle the GNU void* extension. 5127 if (rpointee->isVoidType()) { 5128 if (getLangOptions().CPlusPlus) { 5129 Diag(Loc, diag::err_typecheck_pointer_arith_void_type) 5130 << lex->getSourceRange() << rex->getSourceRange(); 5131 return QualType(); 5132 } 5133 5134 ComplainAboutVoid = true; 5135 } else if (rpointee->isFunctionType()) { 5136 if (getLangOptions().CPlusPlus) { 5137 Diag(Loc, diag::err_typecheck_pointer_arith_function_type) 5138 << rex->getType() << rex->getSourceRange(); 5139 return QualType(); 5140 } 5141 5142 // GNU extension: arithmetic on pointer to function 5143 if (!ComplainAboutFunc) 5144 ComplainAboutFunc = rex; 5145 } else if (!rpointee->isDependentType() && 5146 RequireCompleteType(Loc, rpointee, 5147 PDiag(diag::err_typecheck_sub_ptr_object) 5148 << rex->getSourceRange() 5149 << rex->getType())) 5150 return QualType(); 5151 5152 if (getLangOptions().CPlusPlus) { 5153 // Pointee types must be the same: C++ [expr.add] 5154 if (!Context.hasSameUnqualifiedType(lpointee, rpointee)) { 5155 Diag(Loc, diag::err_typecheck_sub_ptr_compatible) 5156 << lex->getType() << rex->getType() 5157 << lex->getSourceRange() << rex->getSourceRange(); 5158 return QualType(); 5159 } 5160 } else { 5161 // Pointee types must be compatible C99 6.5.6p3 5162 if (!Context.typesAreCompatible( 5163 Context.getCanonicalType(lpointee).getUnqualifiedType(), 5164 Context.getCanonicalType(rpointee).getUnqualifiedType())) { 5165 Diag(Loc, diag::err_typecheck_sub_ptr_compatible) 5166 << lex->getType() << rex->getType() 5167 << lex->getSourceRange() << rex->getSourceRange(); 5168 return QualType(); 5169 } 5170 } 5171 5172 if (ComplainAboutVoid) 5173 Diag(Loc, diag::ext_gnu_void_ptr) 5174 << lex->getSourceRange() << rex->getSourceRange(); 5175 if (ComplainAboutFunc) 5176 Diag(Loc, diag::ext_gnu_ptr_func_arith) 5177 << ComplainAboutFunc->getType() 5178 << ComplainAboutFunc->getSourceRange(); 5179 5180 if (CompLHSTy) *CompLHSTy = lex->getType(); 5181 return Context.getPointerDiffType(); 5182 } 5183 } 5184 5185 return InvalidOperands(Loc, lex, rex); 5186} 5187 5188// C99 6.5.7 5189QualType Sema::CheckShiftOperands(Expr *&lex, Expr *&rex, SourceLocation Loc, 5190 bool isCompAssign) { 5191 // C99 6.5.7p2: Each of the operands shall have integer type. 5192 if (!lex->getType()->isIntegerType() || !rex->getType()->isIntegerType()) 5193 return InvalidOperands(Loc, lex, rex); 5194 5195 // Vector shifts promote their scalar inputs to vector type. 5196 if (lex->getType()->isVectorType() || rex->getType()->isVectorType()) 5197 return CheckVectorOperands(Loc, lex, rex); 5198 5199 // Shifts don't perform usual arithmetic conversions, they just do integer 5200 // promotions on each operand. C99 6.5.7p3 5201 QualType LHSTy = Context.isPromotableBitField(lex); 5202 if (LHSTy.isNull()) { 5203 LHSTy = lex->getType(); 5204 if (LHSTy->isPromotableIntegerType()) 5205 LHSTy = Context.getPromotedIntegerType(LHSTy); 5206 } 5207 if (!isCompAssign) 5208 ImpCastExprToType(lex, LHSTy, CastExpr::CK_IntegralCast); 5209 5210 UsualUnaryConversions(rex); 5211 5212 // Sanity-check shift operands 5213 llvm::APSInt Right; 5214 // Check right/shifter operand 5215 if (!rex->isValueDependent() && 5216 rex->isIntegerConstantExpr(Right, Context)) { 5217 if (Right.isNegative()) 5218 Diag(Loc, diag::warn_shift_negative) << rex->getSourceRange(); 5219 else { 5220 llvm::APInt LeftBits(Right.getBitWidth(), 5221 Context.getTypeSize(lex->getType())); 5222 if (Right.uge(LeftBits)) 5223 Diag(Loc, diag::warn_shift_gt_typewidth) << rex->getSourceRange(); 5224 } 5225 } 5226 5227 // "The type of the result is that of the promoted left operand." 5228 return LHSTy; 5229} 5230 5231// C99 6.5.8, C++ [expr.rel] 5232QualType Sema::CheckCompareOperands(Expr *&lex, Expr *&rex, SourceLocation Loc, 5233 unsigned OpaqueOpc, bool isRelational) { 5234 BinaryOperator::Opcode Opc = (BinaryOperator::Opcode)OpaqueOpc; 5235 5236 // Handle vector comparisons separately. 5237 if (lex->getType()->isVectorType() || rex->getType()->isVectorType()) 5238 return CheckVectorCompareOperands(lex, rex, Loc, isRelational); 5239 5240 CheckSignCompare(lex, rex, Loc, diag::warn_mixed_sign_comparison, 5241 (Opc == BinaryOperator::EQ || Opc == BinaryOperator::NE)); 5242 5243 // C99 6.5.8p3 / C99 6.5.9p4 5244 if (lex->getType()->isArithmeticType() && rex->getType()->isArithmeticType()) 5245 UsualArithmeticConversions(lex, rex); 5246 else { 5247 UsualUnaryConversions(lex); 5248 UsualUnaryConversions(rex); 5249 } 5250 QualType lType = lex->getType(); 5251 QualType rType = rex->getType(); 5252 5253 if (!lType->isFloatingType() 5254 && !(lType->isBlockPointerType() && isRelational)) { 5255 // For non-floating point types, check for self-comparisons of the form 5256 // x == x, x != x, x < x, etc. These always evaluate to a constant, and 5257 // often indicate logic errors in the program. 5258 // NOTE: Don't warn about comparisons of enum constants. These can arise 5259 // from macro expansions, and are usually quite deliberate. 5260 Expr *LHSStripped = lex->IgnoreParens(); 5261 Expr *RHSStripped = rex->IgnoreParens(); 5262 if (DeclRefExpr* DRL = dyn_cast<DeclRefExpr>(LHSStripped)) 5263 if (DeclRefExpr* DRR = dyn_cast<DeclRefExpr>(RHSStripped)) 5264 if (DRL->getDecl() == DRR->getDecl() && 5265 !isa<EnumConstantDecl>(DRL->getDecl())) 5266 DiagRuntimeBehavior(Loc, PDiag(diag::warn_selfcomparison)); 5267 5268 if (isa<CastExpr>(LHSStripped)) 5269 LHSStripped = LHSStripped->IgnoreParenCasts(); 5270 if (isa<CastExpr>(RHSStripped)) 5271 RHSStripped = RHSStripped->IgnoreParenCasts(); 5272 5273 // Warn about comparisons against a string constant (unless the other 5274 // operand is null), the user probably wants strcmp. 5275 Expr *literalString = 0; 5276 Expr *literalStringStripped = 0; 5277 if ((isa<StringLiteral>(LHSStripped) || isa<ObjCEncodeExpr>(LHSStripped)) && 5278 !RHSStripped->isNullPointerConstant(Context, 5279 Expr::NPC_ValueDependentIsNull)) { 5280 literalString = lex; 5281 literalStringStripped = LHSStripped; 5282 } else if ((isa<StringLiteral>(RHSStripped) || 5283 isa<ObjCEncodeExpr>(RHSStripped)) && 5284 !LHSStripped->isNullPointerConstant(Context, 5285 Expr::NPC_ValueDependentIsNull)) { 5286 literalString = rex; 5287 literalStringStripped = RHSStripped; 5288 } 5289 5290 if (literalString) { 5291 std::string resultComparison; 5292 switch (Opc) { 5293 case BinaryOperator::LT: resultComparison = ") < 0"; break; 5294 case BinaryOperator::GT: resultComparison = ") > 0"; break; 5295 case BinaryOperator::LE: resultComparison = ") <= 0"; break; 5296 case BinaryOperator::GE: resultComparison = ") >= 0"; break; 5297 case BinaryOperator::EQ: resultComparison = ") == 0"; break; 5298 case BinaryOperator::NE: resultComparison = ") != 0"; break; 5299 default: assert(false && "Invalid comparison operator"); 5300 } 5301 5302 DiagRuntimeBehavior(Loc, 5303 PDiag(diag::warn_stringcompare) 5304 << isa<ObjCEncodeExpr>(literalStringStripped) 5305 << literalString->getSourceRange() 5306 << CodeModificationHint::CreateReplacement(SourceRange(Loc), ", ") 5307 << CodeModificationHint::CreateInsertion(lex->getLocStart(), 5308 "strcmp(") 5309 << CodeModificationHint::CreateInsertion( 5310 PP.getLocForEndOfToken(rex->getLocEnd()), 5311 resultComparison)); 5312 } 5313 } 5314 5315 // The result of comparisons is 'bool' in C++, 'int' in C. 5316 QualType ResultTy = getLangOptions().CPlusPlus ? Context.BoolTy:Context.IntTy; 5317 5318 if (isRelational) { 5319 if (lType->isRealType() && rType->isRealType()) 5320 return ResultTy; 5321 } else { 5322 // Check for comparisons of floating point operands using != and ==. 5323 if (lType->isFloatingType() && rType->isFloatingType()) 5324 CheckFloatComparison(Loc,lex,rex); 5325 5326 if (lType->isArithmeticType() && rType->isArithmeticType()) 5327 return ResultTy; 5328 } 5329 5330 bool LHSIsNull = lex->isNullPointerConstant(Context, 5331 Expr::NPC_ValueDependentIsNull); 5332 bool RHSIsNull = rex->isNullPointerConstant(Context, 5333 Expr::NPC_ValueDependentIsNull); 5334 5335 // All of the following pointer related warnings are GCC extensions, except 5336 // when handling null pointer constants. One day, we can consider making them 5337 // errors (when -pedantic-errors is enabled). 5338 if (lType->isPointerType() && rType->isPointerType()) { // C99 6.5.8p2 5339 QualType LCanPointeeTy = 5340 Context.getCanonicalType(lType->getAs<PointerType>()->getPointeeType()); 5341 QualType RCanPointeeTy = 5342 Context.getCanonicalType(rType->getAs<PointerType>()->getPointeeType()); 5343 5344 if (getLangOptions().CPlusPlus) { 5345 if (LCanPointeeTy == RCanPointeeTy) 5346 return ResultTy; 5347 if (!isRelational && 5348 (LCanPointeeTy->isVoidType() || RCanPointeeTy->isVoidType())) { 5349 // Valid unless comparison between non-null pointer and function pointer 5350 // This is a gcc extension compatibility comparison. 5351 if ((LCanPointeeTy->isFunctionType() || RCanPointeeTy->isFunctionType()) 5352 && !LHSIsNull && !RHSIsNull) { 5353 Diag(Loc, diag::ext_typecheck_comparison_of_fptr_to_void) 5354 << lType << rType << lex->getSourceRange() << rex->getSourceRange(); 5355 ImpCastExprToType(rex, lType, CastExpr::CK_BitCast); 5356 return ResultTy; 5357 } 5358 } 5359 // C++ [expr.rel]p2: 5360 // [...] Pointer conversions (4.10) and qualification 5361 // conversions (4.4) are performed on pointer operands (or on 5362 // a pointer operand and a null pointer constant) to bring 5363 // them to their composite pointer type. [...] 5364 // 5365 // C++ [expr.eq]p1 uses the same notion for (in)equality 5366 // comparisons of pointers. 5367 QualType T = FindCompositePointerType(lex, rex); 5368 if (T.isNull()) { 5369 Diag(Loc, diag::err_typecheck_comparison_of_distinct_pointers) 5370 << lType << rType << lex->getSourceRange() << rex->getSourceRange(); 5371 return QualType(); 5372 } 5373 5374 ImpCastExprToType(lex, T, CastExpr::CK_BitCast); 5375 ImpCastExprToType(rex, T, CastExpr::CK_BitCast); 5376 return ResultTy; 5377 } 5378 // C99 6.5.9p2 and C99 6.5.8p2 5379 if (Context.typesAreCompatible(LCanPointeeTy.getUnqualifiedType(), 5380 RCanPointeeTy.getUnqualifiedType())) { 5381 // Valid unless a relational comparison of function pointers 5382 if (isRelational && LCanPointeeTy->isFunctionType()) { 5383 Diag(Loc, diag::ext_typecheck_ordered_comparison_of_function_pointers) 5384 << lType << rType << lex->getSourceRange() << rex->getSourceRange(); 5385 } 5386 } else if (!isRelational && 5387 (LCanPointeeTy->isVoidType() || RCanPointeeTy->isVoidType())) { 5388 // Valid unless comparison between non-null pointer and function pointer 5389 if ((LCanPointeeTy->isFunctionType() || RCanPointeeTy->isFunctionType()) 5390 && !LHSIsNull && !RHSIsNull) { 5391 Diag(Loc, diag::ext_typecheck_comparison_of_fptr_to_void) 5392 << lType << rType << lex->getSourceRange() << rex->getSourceRange(); 5393 } 5394 } else { 5395 // Invalid 5396 Diag(Loc, diag::ext_typecheck_comparison_of_distinct_pointers) 5397 << lType << rType << lex->getSourceRange() << rex->getSourceRange(); 5398 } 5399 if (LCanPointeeTy != RCanPointeeTy) 5400 ImpCastExprToType(rex, lType, CastExpr::CK_BitCast); 5401 return ResultTy; 5402 } 5403 5404 if (getLangOptions().CPlusPlus) { 5405 // Comparison of pointers with null pointer constants and equality 5406 // comparisons of member pointers to null pointer constants. 5407 if (RHSIsNull && 5408 (lType->isPointerType() || 5409 (!isRelational && lType->isMemberPointerType()))) { 5410 ImpCastExprToType(rex, lType, CastExpr::CK_NullToMemberPointer); 5411 return ResultTy; 5412 } 5413 if (LHSIsNull && 5414 (rType->isPointerType() || 5415 (!isRelational && rType->isMemberPointerType()))) { 5416 ImpCastExprToType(lex, rType, CastExpr::CK_NullToMemberPointer); 5417 return ResultTy; 5418 } 5419 5420 // Comparison of member pointers. 5421 if (!isRelational && 5422 lType->isMemberPointerType() && rType->isMemberPointerType()) { 5423 // C++ [expr.eq]p2: 5424 // In addition, pointers to members can be compared, or a pointer to 5425 // member and a null pointer constant. Pointer to member conversions 5426 // (4.11) and qualification conversions (4.4) are performed to bring 5427 // them to a common type. If one operand is a null pointer constant, 5428 // the common type is the type of the other operand. Otherwise, the 5429 // common type is a pointer to member type similar (4.4) to the type 5430 // of one of the operands, with a cv-qualification signature (4.4) 5431 // that is the union of the cv-qualification signatures of the operand 5432 // types. 5433 QualType T = FindCompositePointerType(lex, rex); 5434 if (T.isNull()) { 5435 Diag(Loc, diag::err_typecheck_comparison_of_distinct_pointers) 5436 << lType << rType << lex->getSourceRange() << rex->getSourceRange(); 5437 return QualType(); 5438 } 5439 5440 ImpCastExprToType(lex, T, CastExpr::CK_BitCast); 5441 ImpCastExprToType(rex, T, CastExpr::CK_BitCast); 5442 return ResultTy; 5443 } 5444 5445 // Comparison of nullptr_t with itself. 5446 if (lType->isNullPtrType() && rType->isNullPtrType()) 5447 return ResultTy; 5448 } 5449 5450 // Handle block pointer types. 5451 if (!isRelational && lType->isBlockPointerType() && rType->isBlockPointerType()) { 5452 QualType lpointee = lType->getAs<BlockPointerType>()->getPointeeType(); 5453 QualType rpointee = rType->getAs<BlockPointerType>()->getPointeeType(); 5454 5455 if (!LHSIsNull && !RHSIsNull && 5456 !Context.typesAreCompatible(lpointee, rpointee)) { 5457 Diag(Loc, diag::err_typecheck_comparison_of_distinct_blocks) 5458 << lType << rType << lex->getSourceRange() << rex->getSourceRange(); 5459 } 5460 ImpCastExprToType(rex, lType, CastExpr::CK_BitCast); 5461 return ResultTy; 5462 } 5463 // Allow block pointers to be compared with null pointer constants. 5464 if (!isRelational 5465 && ((lType->isBlockPointerType() && rType->isPointerType()) 5466 || (lType->isPointerType() && rType->isBlockPointerType()))) { 5467 if (!LHSIsNull && !RHSIsNull) { 5468 if (!((rType->isPointerType() && rType->getAs<PointerType>() 5469 ->getPointeeType()->isVoidType()) 5470 || (lType->isPointerType() && lType->getAs<PointerType>() 5471 ->getPointeeType()->isVoidType()))) 5472 Diag(Loc, diag::err_typecheck_comparison_of_distinct_blocks) 5473 << lType << rType << lex->getSourceRange() << rex->getSourceRange(); 5474 } 5475 ImpCastExprToType(rex, lType, CastExpr::CK_BitCast); 5476 return ResultTy; 5477 } 5478 5479 if ((lType->isObjCObjectPointerType() || rType->isObjCObjectPointerType())) { 5480 if (lType->isPointerType() || rType->isPointerType()) { 5481 const PointerType *LPT = lType->getAs<PointerType>(); 5482 const PointerType *RPT = rType->getAs<PointerType>(); 5483 bool LPtrToVoid = LPT ? 5484 Context.getCanonicalType(LPT->getPointeeType())->isVoidType() : false; 5485 bool RPtrToVoid = RPT ? 5486 Context.getCanonicalType(RPT->getPointeeType())->isVoidType() : false; 5487 5488 if (!LPtrToVoid && !RPtrToVoid && 5489 !Context.typesAreCompatible(lType, rType)) { 5490 Diag(Loc, diag::ext_typecheck_comparison_of_distinct_pointers) 5491 << lType << rType << lex->getSourceRange() << rex->getSourceRange(); 5492 } 5493 ImpCastExprToType(rex, lType, CastExpr::CK_BitCast); 5494 return ResultTy; 5495 } 5496 if (lType->isObjCObjectPointerType() && rType->isObjCObjectPointerType()) { 5497 if (!Context.areComparableObjCPointerTypes(lType, rType)) 5498 Diag(Loc, diag::ext_typecheck_comparison_of_distinct_pointers) 5499 << lType << rType << lex->getSourceRange() << rex->getSourceRange(); 5500 ImpCastExprToType(rex, lType, CastExpr::CK_BitCast); 5501 return ResultTy; 5502 } 5503 } 5504 if (lType->isAnyPointerType() && rType->isIntegerType()) { 5505 unsigned DiagID = 0; 5506 if (RHSIsNull) { 5507 if (isRelational) 5508 DiagID = diag::ext_typecheck_ordered_comparison_of_pointer_and_zero; 5509 } else if (isRelational) 5510 DiagID = diag::ext_typecheck_ordered_comparison_of_pointer_integer; 5511 else 5512 DiagID = diag::ext_typecheck_comparison_of_pointer_integer; 5513 5514 if (DiagID) { 5515 Diag(Loc, DiagID) 5516 << lType << rType << lex->getSourceRange() << rex->getSourceRange(); 5517 } 5518 ImpCastExprToType(rex, lType, CastExpr::CK_IntegralToPointer); 5519 return ResultTy; 5520 } 5521 if (lType->isIntegerType() && rType->isAnyPointerType()) { 5522 unsigned DiagID = 0; 5523 if (LHSIsNull) { 5524 if (isRelational) 5525 DiagID = diag::ext_typecheck_ordered_comparison_of_pointer_and_zero; 5526 } else if (isRelational) 5527 DiagID = diag::ext_typecheck_ordered_comparison_of_pointer_integer; 5528 else 5529 DiagID = diag::ext_typecheck_comparison_of_pointer_integer; 5530 5531 if (DiagID) { 5532 Diag(Loc, DiagID) 5533 << lType << rType << lex->getSourceRange() << rex->getSourceRange(); 5534 } 5535 ImpCastExprToType(lex, rType, CastExpr::CK_IntegralToPointer); 5536 return ResultTy; 5537 } 5538 // Handle block pointers. 5539 if (!isRelational && RHSIsNull 5540 && lType->isBlockPointerType() && rType->isIntegerType()) { 5541 ImpCastExprToType(rex, lType, CastExpr::CK_IntegralToPointer); 5542 return ResultTy; 5543 } 5544 if (!isRelational && LHSIsNull 5545 && lType->isIntegerType() && rType->isBlockPointerType()) { 5546 ImpCastExprToType(lex, rType, CastExpr::CK_IntegralToPointer); 5547 return ResultTy; 5548 } 5549 return InvalidOperands(Loc, lex, rex); 5550} 5551 5552/// CheckVectorCompareOperands - vector comparisons are a clang extension that 5553/// operates on extended vector types. Instead of producing an IntTy result, 5554/// like a scalar comparison, a vector comparison produces a vector of integer 5555/// types. 5556QualType Sema::CheckVectorCompareOperands(Expr *&lex, Expr *&rex, 5557 SourceLocation Loc, 5558 bool isRelational) { 5559 // Check to make sure we're operating on vectors of the same type and width, 5560 // Allowing one side to be a scalar of element type. 5561 QualType vType = CheckVectorOperands(Loc, lex, rex); 5562 if (vType.isNull()) 5563 return vType; 5564 5565 QualType lType = lex->getType(); 5566 QualType rType = rex->getType(); 5567 5568 // For non-floating point types, check for self-comparisons of the form 5569 // x == x, x != x, x < x, etc. These always evaluate to a constant, and 5570 // often indicate logic errors in the program. 5571 if (!lType->isFloatingType()) { 5572 if (DeclRefExpr* DRL = dyn_cast<DeclRefExpr>(lex->IgnoreParens())) 5573 if (DeclRefExpr* DRR = dyn_cast<DeclRefExpr>(rex->IgnoreParens())) 5574 if (DRL->getDecl() == DRR->getDecl()) 5575 DiagRuntimeBehavior(Loc, PDiag(diag::warn_selfcomparison)); 5576 } 5577 5578 // Check for comparisons of floating point operands using != and ==. 5579 if (!isRelational && lType->isFloatingType()) { 5580 assert (rType->isFloatingType()); 5581 CheckFloatComparison(Loc,lex,rex); 5582 } 5583 5584 // Return the type for the comparison, which is the same as vector type for 5585 // integer vectors, or an integer type of identical size and number of 5586 // elements for floating point vectors. 5587 if (lType->isIntegerType()) 5588 return lType; 5589 5590 const VectorType *VTy = lType->getAs<VectorType>(); 5591 unsigned TypeSize = Context.getTypeSize(VTy->getElementType()); 5592 if (TypeSize == Context.getTypeSize(Context.IntTy)) 5593 return Context.getExtVectorType(Context.IntTy, VTy->getNumElements()); 5594 if (TypeSize == Context.getTypeSize(Context.LongTy)) 5595 return Context.getExtVectorType(Context.LongTy, VTy->getNumElements()); 5596 5597 assert(TypeSize == Context.getTypeSize(Context.LongLongTy) && 5598 "Unhandled vector element size in vector compare"); 5599 return Context.getExtVectorType(Context.LongLongTy, VTy->getNumElements()); 5600} 5601 5602inline QualType Sema::CheckBitwiseOperands( 5603 Expr *&lex, Expr *&rex, SourceLocation Loc, bool isCompAssign) { 5604 if (lex->getType()->isVectorType() || rex->getType()->isVectorType()) 5605 return CheckVectorOperands(Loc, lex, rex); 5606 5607 QualType compType = UsualArithmeticConversions(lex, rex, isCompAssign); 5608 5609 if (lex->getType()->isIntegerType() && rex->getType()->isIntegerType()) 5610 return compType; 5611 return InvalidOperands(Loc, lex, rex); 5612} 5613 5614inline QualType Sema::CheckLogicalOperands( // C99 6.5.[13,14] 5615 Expr *&lex, Expr *&rex, SourceLocation Loc) { 5616 if (!Context.getLangOptions().CPlusPlus) { 5617 UsualUnaryConversions(lex); 5618 UsualUnaryConversions(rex); 5619 5620 if (!lex->getType()->isScalarType() || !rex->getType()->isScalarType()) 5621 return InvalidOperands(Loc, lex, rex); 5622 5623 return Context.IntTy; 5624 } 5625 5626 // C++ [expr.log.and]p1 5627 // C++ [expr.log.or]p1 5628 // The operands are both implicitly converted to type bool (clause 4). 5629 StandardConversionSequence LHS; 5630 if (!IsStandardConversion(lex, Context.BoolTy, 5631 /*InOverloadResolution=*/false, LHS)) 5632 return InvalidOperands(Loc, lex, rex); 5633 5634 if (PerformImplicitConversion(lex, Context.BoolTy, LHS, 5635 AA_Passing, /*IgnoreBaseAccess=*/false)) 5636 return InvalidOperands(Loc, lex, rex); 5637 5638 StandardConversionSequence RHS; 5639 if (!IsStandardConversion(rex, Context.BoolTy, 5640 /*InOverloadResolution=*/false, RHS)) 5641 return InvalidOperands(Loc, lex, rex); 5642 5643 if (PerformImplicitConversion(rex, Context.BoolTy, RHS, 5644 AA_Passing, /*IgnoreBaseAccess=*/false)) 5645 return InvalidOperands(Loc, lex, rex); 5646 5647 // C++ [expr.log.and]p2 5648 // C++ [expr.log.or]p2 5649 // The result is a bool. 5650 return Context.BoolTy; 5651} 5652 5653/// IsReadonlyProperty - Verify that otherwise a valid l-value expression 5654/// is a read-only property; return true if so. A readonly property expression 5655/// depends on various declarations and thus must be treated specially. 5656/// 5657static bool IsReadonlyProperty(Expr *E, Sema &S) { 5658 if (E->getStmtClass() == Expr::ObjCPropertyRefExprClass) { 5659 const ObjCPropertyRefExpr* PropExpr = cast<ObjCPropertyRefExpr>(E); 5660 if (ObjCPropertyDecl *PDecl = PropExpr->getProperty()) { 5661 QualType BaseType = PropExpr->getBase()->getType(); 5662 if (const ObjCObjectPointerType *OPT = 5663 BaseType->getAsObjCInterfacePointerType()) 5664 if (ObjCInterfaceDecl *IFace = OPT->getInterfaceDecl()) 5665 if (S.isPropertyReadonly(PDecl, IFace)) 5666 return true; 5667 } 5668 } 5669 return false; 5670} 5671 5672/// CheckForModifiableLvalue - Verify that E is a modifiable lvalue. If not, 5673/// emit an error and return true. If so, return false. 5674static bool CheckForModifiableLvalue(Expr *E, SourceLocation Loc, Sema &S) { 5675 SourceLocation OrigLoc = Loc; 5676 Expr::isModifiableLvalueResult IsLV = E->isModifiableLvalue(S.Context, 5677 &Loc); 5678 if (IsLV == Expr::MLV_Valid && IsReadonlyProperty(E, S)) 5679 IsLV = Expr::MLV_ReadonlyProperty; 5680 if (IsLV == Expr::MLV_Valid) 5681 return false; 5682 5683 unsigned Diag = 0; 5684 bool NeedType = false; 5685 switch (IsLV) { // C99 6.5.16p2 5686 case Expr::MLV_ConstQualified: Diag = diag::err_typecheck_assign_const; break; 5687 case Expr::MLV_ArrayType: 5688 Diag = diag::err_typecheck_array_not_modifiable_lvalue; 5689 NeedType = true; 5690 break; 5691 case Expr::MLV_NotObjectType: 5692 Diag = diag::err_typecheck_non_object_not_modifiable_lvalue; 5693 NeedType = true; 5694 break; 5695 case Expr::MLV_LValueCast: 5696 Diag = diag::err_typecheck_lvalue_casts_not_supported; 5697 break; 5698 case Expr::MLV_Valid: 5699 llvm_unreachable("did not take early return for MLV_Valid"); 5700 case Expr::MLV_InvalidExpression: 5701 case Expr::MLV_MemberFunction: 5702 case Expr::MLV_ClassTemporary: 5703 Diag = diag::err_typecheck_expression_not_modifiable_lvalue; 5704 break; 5705 case Expr::MLV_IncompleteType: 5706 case Expr::MLV_IncompleteVoidType: 5707 return S.RequireCompleteType(Loc, E->getType(), 5708 PDiag(diag::err_typecheck_incomplete_type_not_modifiable_lvalue) 5709 << E->getSourceRange()); 5710 case Expr::MLV_DuplicateVectorComponents: 5711 Diag = diag::err_typecheck_duplicate_vector_components_not_mlvalue; 5712 break; 5713 case Expr::MLV_NotBlockQualified: 5714 Diag = diag::err_block_decl_ref_not_modifiable_lvalue; 5715 break; 5716 case Expr::MLV_ReadonlyProperty: 5717 Diag = diag::error_readonly_property_assignment; 5718 break; 5719 case Expr::MLV_NoSetterProperty: 5720 Diag = diag::error_nosetter_property_assignment; 5721 break; 5722 case Expr::MLV_SubObjCPropertySetting: 5723 Diag = diag::error_no_subobject_property_setting; 5724 break; 5725 case Expr::MLV_SubObjCPropertyGetterSetting: 5726 Diag = diag::error_no_subobject_property_getter_setting; 5727 break; 5728 } 5729 5730 SourceRange Assign; 5731 if (Loc != OrigLoc) 5732 Assign = SourceRange(OrigLoc, OrigLoc); 5733 if (NeedType) 5734 S.Diag(Loc, Diag) << E->getType() << E->getSourceRange() << Assign; 5735 else 5736 S.Diag(Loc, Diag) << E->getSourceRange() << Assign; 5737 return true; 5738} 5739 5740 5741 5742// C99 6.5.16.1 5743QualType Sema::CheckAssignmentOperands(Expr *LHS, Expr *&RHS, 5744 SourceLocation Loc, 5745 QualType CompoundType) { 5746 // Verify that LHS is a modifiable lvalue, and emit error if not. 5747 if (CheckForModifiableLvalue(LHS, Loc, *this)) 5748 return QualType(); 5749 5750 QualType LHSType = LHS->getType(); 5751 QualType RHSType = CompoundType.isNull() ? RHS->getType() : CompoundType; 5752 5753 AssignConvertType ConvTy; 5754 if (CompoundType.isNull()) { 5755 // Simple assignment "x = y". 5756 ConvTy = CheckSingleAssignmentConstraints(LHSType, RHS); 5757 // Special case of NSObject attributes on c-style pointer types. 5758 if (ConvTy == IncompatiblePointer && 5759 ((Context.isObjCNSObjectType(LHSType) && 5760 RHSType->isObjCObjectPointerType()) || 5761 (Context.isObjCNSObjectType(RHSType) && 5762 LHSType->isObjCObjectPointerType()))) 5763 ConvTy = Compatible; 5764 5765 // If the RHS is a unary plus or minus, check to see if they = and + are 5766 // right next to each other. If so, the user may have typo'd "x =+ 4" 5767 // instead of "x += 4". 5768 Expr *RHSCheck = RHS; 5769 if (ImplicitCastExpr *ICE = dyn_cast<ImplicitCastExpr>(RHSCheck)) 5770 RHSCheck = ICE->getSubExpr(); 5771 if (UnaryOperator *UO = dyn_cast<UnaryOperator>(RHSCheck)) { 5772 if ((UO->getOpcode() == UnaryOperator::Plus || 5773 UO->getOpcode() == UnaryOperator::Minus) && 5774 Loc.isFileID() && UO->getOperatorLoc().isFileID() && 5775 // Only if the two operators are exactly adjacent. 5776 Loc.getFileLocWithOffset(1) == UO->getOperatorLoc() && 5777 // And there is a space or other character before the subexpr of the 5778 // unary +/-. We don't want to warn on "x=-1". 5779 Loc.getFileLocWithOffset(2) != UO->getSubExpr()->getLocStart() && 5780 UO->getSubExpr()->getLocStart().isFileID()) { 5781 Diag(Loc, diag::warn_not_compound_assign) 5782 << (UO->getOpcode() == UnaryOperator::Plus ? "+" : "-") 5783 << SourceRange(UO->getOperatorLoc(), UO->getOperatorLoc()); 5784 } 5785 } 5786 } else { 5787 // Compound assignment "x += y" 5788 ConvTy = CheckAssignmentConstraints(LHSType, RHSType); 5789 } 5790 5791 if (DiagnoseAssignmentResult(ConvTy, Loc, LHSType, RHSType, 5792 RHS, AA_Assigning)) 5793 return QualType(); 5794 5795 // C99 6.5.16p3: The type of an assignment expression is the type of the 5796 // left operand unless the left operand has qualified type, in which case 5797 // it is the unqualified version of the type of the left operand. 5798 // C99 6.5.16.1p2: In simple assignment, the value of the right operand 5799 // is converted to the type of the assignment expression (above). 5800 // C++ 5.17p1: the type of the assignment expression is that of its left 5801 // operand. 5802 return LHSType.getUnqualifiedType(); 5803} 5804 5805// C99 6.5.17 5806QualType Sema::CheckCommaOperands(Expr *LHS, Expr *&RHS, SourceLocation Loc) { 5807 // Comma performs lvalue conversion (C99 6.3.2.1), but not unary conversions. 5808 // C++ does not perform this conversion (C++ [expr.comma]p1). 5809 if (!getLangOptions().CPlusPlus) 5810 DefaultFunctionArrayLvalueConversion(RHS); 5811 5812 // FIXME: Check that RHS type is complete in C mode (it's legal for it to be 5813 // incomplete in C++). 5814 5815 return RHS->getType(); 5816} 5817 5818/// CheckIncrementDecrementOperand - unlike most "Check" methods, this routine 5819/// doesn't need to call UsualUnaryConversions or UsualArithmeticConversions. 5820QualType Sema::CheckIncrementDecrementOperand(Expr *Op, SourceLocation OpLoc, 5821 bool isInc) { 5822 if (Op->isTypeDependent()) 5823 return Context.DependentTy; 5824 5825 QualType ResType = Op->getType(); 5826 assert(!ResType.isNull() && "no type for increment/decrement expression"); 5827 5828 if (getLangOptions().CPlusPlus && ResType->isBooleanType()) { 5829 // Decrement of bool is not allowed. 5830 if (!isInc) { 5831 Diag(OpLoc, diag::err_decrement_bool) << Op->getSourceRange(); 5832 return QualType(); 5833 } 5834 // Increment of bool sets it to true, but is deprecated. 5835 Diag(OpLoc, diag::warn_increment_bool) << Op->getSourceRange(); 5836 } else if (ResType->isRealType()) { 5837 // OK! 5838 } else if (ResType->isAnyPointerType()) { 5839 QualType PointeeTy = ResType->getPointeeType(); 5840 5841 // C99 6.5.2.4p2, 6.5.6p2 5842 if (PointeeTy->isVoidType()) { 5843 if (getLangOptions().CPlusPlus) { 5844 Diag(OpLoc, diag::err_typecheck_pointer_arith_void_type) 5845 << Op->getSourceRange(); 5846 return QualType(); 5847 } 5848 5849 // Pointer to void is a GNU extension in C. 5850 Diag(OpLoc, diag::ext_gnu_void_ptr) << Op->getSourceRange(); 5851 } else if (PointeeTy->isFunctionType()) { 5852 if (getLangOptions().CPlusPlus) { 5853 Diag(OpLoc, diag::err_typecheck_pointer_arith_function_type) 5854 << Op->getType() << Op->getSourceRange(); 5855 return QualType(); 5856 } 5857 5858 Diag(OpLoc, diag::ext_gnu_ptr_func_arith) 5859 << ResType << Op->getSourceRange(); 5860 } else if (RequireCompleteType(OpLoc, PointeeTy, 5861 PDiag(diag::err_typecheck_arithmetic_incomplete_type) 5862 << Op->getSourceRange() 5863 << ResType)) 5864 return QualType(); 5865 // Diagnose bad cases where we step over interface counts. 5866 else if (PointeeTy->isObjCInterfaceType() && LangOpts.ObjCNonFragileABI) { 5867 Diag(OpLoc, diag::err_arithmetic_nonfragile_interface) 5868 << PointeeTy << Op->getSourceRange(); 5869 return QualType(); 5870 } 5871 } else if (ResType->isAnyComplexType()) { 5872 // C99 does not support ++/-- on complex types, we allow as an extension. 5873 Diag(OpLoc, diag::ext_integer_increment_complex) 5874 << ResType << Op->getSourceRange(); 5875 } else { 5876 Diag(OpLoc, diag::err_typecheck_illegal_increment_decrement) 5877 << ResType << int(isInc) << Op->getSourceRange(); 5878 return QualType(); 5879 } 5880 // At this point, we know we have a real, complex or pointer type. 5881 // Now make sure the operand is a modifiable lvalue. 5882 if (CheckForModifiableLvalue(Op, OpLoc, *this)) 5883 return QualType(); 5884 return ResType; 5885} 5886 5887/// getPrimaryDecl - Helper function for CheckAddressOfOperand(). 5888/// This routine allows us to typecheck complex/recursive expressions 5889/// where the declaration is needed for type checking. We only need to 5890/// handle cases when the expression references a function designator 5891/// or is an lvalue. Here are some examples: 5892/// - &(x) => x 5893/// - &*****f => f for f a function designator. 5894/// - &s.xx => s 5895/// - &s.zz[1].yy -> s, if zz is an array 5896/// - *(x + 1) -> x, if x is an array 5897/// - &"123"[2] -> 0 5898/// - & __real__ x -> x 5899static NamedDecl *getPrimaryDecl(Expr *E) { 5900 switch (E->getStmtClass()) { 5901 case Stmt::DeclRefExprClass: 5902 return cast<DeclRefExpr>(E)->getDecl(); 5903 case Stmt::MemberExprClass: 5904 // If this is an arrow operator, the address is an offset from 5905 // the base's value, so the object the base refers to is 5906 // irrelevant. 5907 if (cast<MemberExpr>(E)->isArrow()) 5908 return 0; 5909 // Otherwise, the expression refers to a part of the base 5910 return getPrimaryDecl(cast<MemberExpr>(E)->getBase()); 5911 case Stmt::ArraySubscriptExprClass: { 5912 // FIXME: This code shouldn't be necessary! We should catch the implicit 5913 // promotion of register arrays earlier. 5914 Expr* Base = cast<ArraySubscriptExpr>(E)->getBase(); 5915 if (ImplicitCastExpr* ICE = dyn_cast<ImplicitCastExpr>(Base)) { 5916 if (ICE->getSubExpr()->getType()->isArrayType()) 5917 return getPrimaryDecl(ICE->getSubExpr()); 5918 } 5919 return 0; 5920 } 5921 case Stmt::UnaryOperatorClass: { 5922 UnaryOperator *UO = cast<UnaryOperator>(E); 5923 5924 switch(UO->getOpcode()) { 5925 case UnaryOperator::Real: 5926 case UnaryOperator::Imag: 5927 case UnaryOperator::Extension: 5928 return getPrimaryDecl(UO->getSubExpr()); 5929 default: 5930 return 0; 5931 } 5932 } 5933 case Stmt::ParenExprClass: 5934 return getPrimaryDecl(cast<ParenExpr>(E)->getSubExpr()); 5935 case Stmt::ImplicitCastExprClass: 5936 // If the result of an implicit cast is an l-value, we care about 5937 // the sub-expression; otherwise, the result here doesn't matter. 5938 return getPrimaryDecl(cast<ImplicitCastExpr>(E)->getSubExpr()); 5939 default: 5940 return 0; 5941 } 5942} 5943 5944/// CheckAddressOfOperand - The operand of & must be either a function 5945/// designator or an lvalue designating an object. If it is an lvalue, the 5946/// object cannot be declared with storage class register or be a bit field. 5947/// Note: The usual conversions are *not* applied to the operand of the & 5948/// operator (C99 6.3.2.1p[2-4]), and its result is never an lvalue. 5949/// In C++, the operand might be an overloaded function name, in which case 5950/// we allow the '&' but retain the overloaded-function type. 5951QualType Sema::CheckAddressOfOperand(Expr *op, SourceLocation OpLoc) { 5952 // Make sure to ignore parentheses in subsequent checks 5953 op = op->IgnoreParens(); 5954 5955 if (op->isTypeDependent()) 5956 return Context.DependentTy; 5957 5958 if (getLangOptions().C99) { 5959 // Implement C99-only parts of addressof rules. 5960 if (UnaryOperator* uOp = dyn_cast<UnaryOperator>(op)) { 5961 if (uOp->getOpcode() == UnaryOperator::Deref) 5962 // Per C99 6.5.3.2, the address of a deref always returns a valid result 5963 // (assuming the deref expression is valid). 5964 return uOp->getSubExpr()->getType(); 5965 } 5966 // Technically, there should be a check for array subscript 5967 // expressions here, but the result of one is always an lvalue anyway. 5968 } 5969 NamedDecl *dcl = getPrimaryDecl(op); 5970 Expr::isLvalueResult lval = op->isLvalue(Context); 5971 5972 MemberExpr *ME = dyn_cast<MemberExpr>(op); 5973 if (lval == Expr::LV_MemberFunction && ME && 5974 isa<CXXMethodDecl>(ME->getMemberDecl())) { 5975 ValueDecl *dcl = cast<MemberExpr>(op)->getMemberDecl(); 5976 // &f where f is a member of the current object, or &o.f, or &p->f 5977 // All these are not allowed, and we need to catch them before the dcl 5978 // branch of the if, below. 5979 Diag(OpLoc, diag::err_unqualified_pointer_member_function) 5980 << dcl; 5981 // FIXME: Improve this diagnostic and provide a fixit. 5982 5983 // Now recover by acting as if the function had been accessed qualified. 5984 return Context.getMemberPointerType(op->getType(), 5985 Context.getTypeDeclType(cast<RecordDecl>(dcl->getDeclContext())) 5986 .getTypePtr()); 5987 } else if (lval == Expr::LV_ClassTemporary) { 5988 Diag(OpLoc, isSFINAEContext()? diag::err_typecheck_addrof_class_temporary 5989 : diag::ext_typecheck_addrof_class_temporary) 5990 << op->getType() << op->getSourceRange(); 5991 if (isSFINAEContext()) 5992 return QualType(); 5993 } else if (lval != Expr::LV_Valid && lval != Expr::LV_IncompleteVoidType) { 5994 // C99 6.5.3.2p1 5995 // The operand must be either an l-value or a function designator 5996 if (!op->getType()->isFunctionType()) { 5997 // FIXME: emit more specific diag... 5998 Diag(OpLoc, diag::err_typecheck_invalid_lvalue_addrof) 5999 << op->getSourceRange(); 6000 return QualType(); 6001 } 6002 } else if (op->getBitField()) { // C99 6.5.3.2p1 6003 // The operand cannot be a bit-field 6004 Diag(OpLoc, diag::err_typecheck_address_of) 6005 << "bit-field" << op->getSourceRange(); 6006 return QualType(); 6007 } else if (op->refersToVectorElement()) { 6008 // The operand cannot be an element of a vector 6009 Diag(OpLoc, diag::err_typecheck_address_of) 6010 << "vector element" << op->getSourceRange(); 6011 return QualType(); 6012 } else if (isa<ObjCPropertyRefExpr>(op)) { 6013 // cannot take address of a property expression. 6014 Diag(OpLoc, diag::err_typecheck_address_of) 6015 << "property expression" << op->getSourceRange(); 6016 return QualType(); 6017 } else if (ConditionalOperator *CO = dyn_cast<ConditionalOperator>(op)) { 6018 // FIXME: Can LHS ever be null here? 6019 if (!CheckAddressOfOperand(CO->getTrueExpr(), OpLoc).isNull()) 6020 return CheckAddressOfOperand(CO->getFalseExpr(), OpLoc); 6021 } else if (isa<UnresolvedLookupExpr>(op)) { 6022 return Context.OverloadTy; 6023 } else if (dcl) { // C99 6.5.3.2p1 6024 // We have an lvalue with a decl. Make sure the decl is not declared 6025 // with the register storage-class specifier. 6026 if (const VarDecl *vd = dyn_cast<VarDecl>(dcl)) { 6027 if (vd->getStorageClass() == VarDecl::Register) { 6028 Diag(OpLoc, diag::err_typecheck_address_of) 6029 << "register variable" << op->getSourceRange(); 6030 return QualType(); 6031 } 6032 } else if (isa<FunctionTemplateDecl>(dcl)) { 6033 return Context.OverloadTy; 6034 } else if (FieldDecl *FD = dyn_cast<FieldDecl>(dcl)) { 6035 // Okay: we can take the address of a field. 6036 // Could be a pointer to member, though, if there is an explicit 6037 // scope qualifier for the class. 6038 if (isa<DeclRefExpr>(op) && cast<DeclRefExpr>(op)->getQualifier()) { 6039 DeclContext *Ctx = dcl->getDeclContext(); 6040 if (Ctx && Ctx->isRecord()) { 6041 if (FD->getType()->isReferenceType()) { 6042 Diag(OpLoc, 6043 diag::err_cannot_form_pointer_to_member_of_reference_type) 6044 << FD->getDeclName() << FD->getType(); 6045 return QualType(); 6046 } 6047 6048 return Context.getMemberPointerType(op->getType(), 6049 Context.getTypeDeclType(cast<RecordDecl>(Ctx)).getTypePtr()); 6050 } 6051 } 6052 } else if (CXXMethodDecl *MD = dyn_cast<CXXMethodDecl>(dcl)) { 6053 // Okay: we can take the address of a function. 6054 // As above. 6055 if (isa<DeclRefExpr>(op) && cast<DeclRefExpr>(op)->getQualifier() && 6056 MD->isInstance()) 6057 return Context.getMemberPointerType(op->getType(), 6058 Context.getTypeDeclType(MD->getParent()).getTypePtr()); 6059 } else if (!isa<FunctionDecl>(dcl)) 6060 assert(0 && "Unknown/unexpected decl type"); 6061 } 6062 6063 if (lval == Expr::LV_IncompleteVoidType) { 6064 // Taking the address of a void variable is technically illegal, but we 6065 // allow it in cases which are otherwise valid. 6066 // Example: "extern void x; void* y = &x;". 6067 Diag(OpLoc, diag::ext_typecheck_addrof_void) << op->getSourceRange(); 6068 } 6069 6070 // If the operand has type "type", the result has type "pointer to type". 6071 return Context.getPointerType(op->getType()); 6072} 6073 6074QualType Sema::CheckIndirectionOperand(Expr *Op, SourceLocation OpLoc) { 6075 if (Op->isTypeDependent()) 6076 return Context.DependentTy; 6077 6078 UsualUnaryConversions(Op); 6079 QualType Ty = Op->getType(); 6080 6081 // Note that per both C89 and C99, this is always legal, even if ptype is an 6082 // incomplete type or void. It would be possible to warn about dereferencing 6083 // a void pointer, but it's completely well-defined, and such a warning is 6084 // unlikely to catch any mistakes. 6085 if (const PointerType *PT = Ty->getAs<PointerType>()) 6086 return PT->getPointeeType(); 6087 6088 if (const ObjCObjectPointerType *OPT = Ty->getAs<ObjCObjectPointerType>()) 6089 return OPT->getPointeeType(); 6090 6091 Diag(OpLoc, diag::err_typecheck_indirection_requires_pointer) 6092 << Ty << Op->getSourceRange(); 6093 return QualType(); 6094} 6095 6096static inline BinaryOperator::Opcode ConvertTokenKindToBinaryOpcode( 6097 tok::TokenKind Kind) { 6098 BinaryOperator::Opcode Opc; 6099 switch (Kind) { 6100 default: assert(0 && "Unknown binop!"); 6101 case tok::periodstar: Opc = BinaryOperator::PtrMemD; break; 6102 case tok::arrowstar: Opc = BinaryOperator::PtrMemI; break; 6103 case tok::star: Opc = BinaryOperator::Mul; break; 6104 case tok::slash: Opc = BinaryOperator::Div; break; 6105 case tok::percent: Opc = BinaryOperator::Rem; break; 6106 case tok::plus: Opc = BinaryOperator::Add; break; 6107 case tok::minus: Opc = BinaryOperator::Sub; break; 6108 case tok::lessless: Opc = BinaryOperator::Shl; break; 6109 case tok::greatergreater: Opc = BinaryOperator::Shr; break; 6110 case tok::lessequal: Opc = BinaryOperator::LE; break; 6111 case tok::less: Opc = BinaryOperator::LT; break; 6112 case tok::greaterequal: Opc = BinaryOperator::GE; break; 6113 case tok::greater: Opc = BinaryOperator::GT; break; 6114 case tok::exclaimequal: Opc = BinaryOperator::NE; break; 6115 case tok::equalequal: Opc = BinaryOperator::EQ; break; 6116 case tok::amp: Opc = BinaryOperator::And; break; 6117 case tok::caret: Opc = BinaryOperator::Xor; break; 6118 case tok::pipe: Opc = BinaryOperator::Or; break; 6119 case tok::ampamp: Opc = BinaryOperator::LAnd; break; 6120 case tok::pipepipe: Opc = BinaryOperator::LOr; break; 6121 case tok::equal: Opc = BinaryOperator::Assign; break; 6122 case tok::starequal: Opc = BinaryOperator::MulAssign; break; 6123 case tok::slashequal: Opc = BinaryOperator::DivAssign; break; 6124 case tok::percentequal: Opc = BinaryOperator::RemAssign; break; 6125 case tok::plusequal: Opc = BinaryOperator::AddAssign; break; 6126 case tok::minusequal: Opc = BinaryOperator::SubAssign; break; 6127 case tok::lesslessequal: Opc = BinaryOperator::ShlAssign; break; 6128 case tok::greatergreaterequal: Opc = BinaryOperator::ShrAssign; break; 6129 case tok::ampequal: Opc = BinaryOperator::AndAssign; break; 6130 case tok::caretequal: Opc = BinaryOperator::XorAssign; break; 6131 case tok::pipeequal: Opc = BinaryOperator::OrAssign; break; 6132 case tok::comma: Opc = BinaryOperator::Comma; break; 6133 } 6134 return Opc; 6135} 6136 6137static inline UnaryOperator::Opcode ConvertTokenKindToUnaryOpcode( 6138 tok::TokenKind Kind) { 6139 UnaryOperator::Opcode Opc; 6140 switch (Kind) { 6141 default: assert(0 && "Unknown unary op!"); 6142 case tok::plusplus: Opc = UnaryOperator::PreInc; break; 6143 case tok::minusminus: Opc = UnaryOperator::PreDec; break; 6144 case tok::amp: Opc = UnaryOperator::AddrOf; break; 6145 case tok::star: Opc = UnaryOperator::Deref; break; 6146 case tok::plus: Opc = UnaryOperator::Plus; break; 6147 case tok::minus: Opc = UnaryOperator::Minus; break; 6148 case tok::tilde: Opc = UnaryOperator::Not; break; 6149 case tok::exclaim: Opc = UnaryOperator::LNot; break; 6150 case tok::kw___real: Opc = UnaryOperator::Real; break; 6151 case tok::kw___imag: Opc = UnaryOperator::Imag; break; 6152 case tok::kw___extension__: Opc = UnaryOperator::Extension; break; 6153 } 6154 return Opc; 6155} 6156 6157/// CreateBuiltinBinOp - Creates a new built-in binary operation with 6158/// operator @p Opc at location @c TokLoc. This routine only supports 6159/// built-in operations; ActOnBinOp handles overloaded operators. 6160Action::OwningExprResult Sema::CreateBuiltinBinOp(SourceLocation OpLoc, 6161 unsigned Op, 6162 Expr *lhs, Expr *rhs) { 6163 QualType ResultTy; // Result type of the binary operator. 6164 BinaryOperator::Opcode Opc = (BinaryOperator::Opcode)Op; 6165 // The following two variables are used for compound assignment operators 6166 QualType CompLHSTy; // Type of LHS after promotions for computation 6167 QualType CompResultTy; // Type of computation result 6168 6169 switch (Opc) { 6170 case BinaryOperator::Assign: 6171 ResultTy = CheckAssignmentOperands(lhs, rhs, OpLoc, QualType()); 6172 break; 6173 case BinaryOperator::PtrMemD: 6174 case BinaryOperator::PtrMemI: 6175 ResultTy = CheckPointerToMemberOperands(lhs, rhs, OpLoc, 6176 Opc == BinaryOperator::PtrMemI); 6177 break; 6178 case BinaryOperator::Mul: 6179 case BinaryOperator::Div: 6180 ResultTy = CheckMultiplyDivideOperands(lhs, rhs, OpLoc, false, 6181 Opc == BinaryOperator::Div); 6182 break; 6183 case BinaryOperator::Rem: 6184 ResultTy = CheckRemainderOperands(lhs, rhs, OpLoc); 6185 break; 6186 case BinaryOperator::Add: 6187 ResultTy = CheckAdditionOperands(lhs, rhs, OpLoc); 6188 break; 6189 case BinaryOperator::Sub: 6190 ResultTy = CheckSubtractionOperands(lhs, rhs, OpLoc); 6191 break; 6192 case BinaryOperator::Shl: 6193 case BinaryOperator::Shr: 6194 ResultTy = CheckShiftOperands(lhs, rhs, OpLoc); 6195 break; 6196 case BinaryOperator::LE: 6197 case BinaryOperator::LT: 6198 case BinaryOperator::GE: 6199 case BinaryOperator::GT: 6200 ResultTy = CheckCompareOperands(lhs, rhs, OpLoc, Opc, true); 6201 break; 6202 case BinaryOperator::EQ: 6203 case BinaryOperator::NE: 6204 ResultTy = CheckCompareOperands(lhs, rhs, OpLoc, Opc, false); 6205 break; 6206 case BinaryOperator::And: 6207 case BinaryOperator::Xor: 6208 case BinaryOperator::Or: 6209 ResultTy = CheckBitwiseOperands(lhs, rhs, OpLoc); 6210 break; 6211 case BinaryOperator::LAnd: 6212 case BinaryOperator::LOr: 6213 ResultTy = CheckLogicalOperands(lhs, rhs, OpLoc); 6214 break; 6215 case BinaryOperator::MulAssign: 6216 case BinaryOperator::DivAssign: 6217 CompResultTy = CheckMultiplyDivideOperands(lhs, rhs, OpLoc, true, 6218 Opc == BinaryOperator::DivAssign); 6219 CompLHSTy = CompResultTy; 6220 if (!CompResultTy.isNull()) 6221 ResultTy = CheckAssignmentOperands(lhs, rhs, OpLoc, CompResultTy); 6222 break; 6223 case BinaryOperator::RemAssign: 6224 CompResultTy = CheckRemainderOperands(lhs, rhs, OpLoc, true); 6225 CompLHSTy = CompResultTy; 6226 if (!CompResultTy.isNull()) 6227 ResultTy = CheckAssignmentOperands(lhs, rhs, OpLoc, CompResultTy); 6228 break; 6229 case BinaryOperator::AddAssign: 6230 CompResultTy = CheckAdditionOperands(lhs, rhs, OpLoc, &CompLHSTy); 6231 if (!CompResultTy.isNull()) 6232 ResultTy = CheckAssignmentOperands(lhs, rhs, OpLoc, CompResultTy); 6233 break; 6234 case BinaryOperator::SubAssign: 6235 CompResultTy = CheckSubtractionOperands(lhs, rhs, OpLoc, &CompLHSTy); 6236 if (!CompResultTy.isNull()) 6237 ResultTy = CheckAssignmentOperands(lhs, rhs, OpLoc, CompResultTy); 6238 break; 6239 case BinaryOperator::ShlAssign: 6240 case BinaryOperator::ShrAssign: 6241 CompResultTy = CheckShiftOperands(lhs, rhs, OpLoc, true); 6242 CompLHSTy = CompResultTy; 6243 if (!CompResultTy.isNull()) 6244 ResultTy = CheckAssignmentOperands(lhs, rhs, OpLoc, CompResultTy); 6245 break; 6246 case BinaryOperator::AndAssign: 6247 case BinaryOperator::XorAssign: 6248 case BinaryOperator::OrAssign: 6249 CompResultTy = CheckBitwiseOperands(lhs, rhs, OpLoc, true); 6250 CompLHSTy = CompResultTy; 6251 if (!CompResultTy.isNull()) 6252 ResultTy = CheckAssignmentOperands(lhs, rhs, OpLoc, CompResultTy); 6253 break; 6254 case BinaryOperator::Comma: 6255 ResultTy = CheckCommaOperands(lhs, rhs, OpLoc); 6256 break; 6257 } 6258 if (ResultTy.isNull()) 6259 return ExprError(); 6260 if (CompResultTy.isNull()) 6261 return Owned(new (Context) BinaryOperator(lhs, rhs, Opc, ResultTy, OpLoc)); 6262 else 6263 return Owned(new (Context) CompoundAssignOperator(lhs, rhs, Opc, ResultTy, 6264 CompLHSTy, CompResultTy, 6265 OpLoc)); 6266} 6267 6268/// SuggestParentheses - Emit a diagnostic together with a fixit hint that wraps 6269/// ParenRange in parentheses. 6270static void SuggestParentheses(Sema &Self, SourceLocation Loc, 6271 const PartialDiagnostic &PD, 6272 SourceRange ParenRange, 6273 const PartialDiagnostic &SecondPD = PartialDiagnostic(0), 6274 SourceRange SecondParenRange = SourceRange()) { 6275 SourceLocation EndLoc = Self.PP.getLocForEndOfToken(ParenRange.getEnd()); 6276 if (!ParenRange.getEnd().isFileID() || EndLoc.isInvalid()) { 6277 // We can't display the parentheses, so just dig the 6278 // warning/error and return. 6279 Self.Diag(Loc, PD); 6280 return; 6281 } 6282 6283 Self.Diag(Loc, PD) 6284 << CodeModificationHint::CreateInsertion(ParenRange.getBegin(), "(") 6285 << CodeModificationHint::CreateInsertion(EndLoc, ")"); 6286 6287 if (!SecondPD.getDiagID()) 6288 return; 6289 6290 EndLoc = Self.PP.getLocForEndOfToken(SecondParenRange.getEnd()); 6291 if (!SecondParenRange.getEnd().isFileID() || EndLoc.isInvalid()) { 6292 // We can't display the parentheses, so just dig the 6293 // warning/error and return. 6294 Self.Diag(Loc, SecondPD); 6295 return; 6296 } 6297 6298 Self.Diag(Loc, SecondPD) 6299 << CodeModificationHint::CreateInsertion(SecondParenRange.getBegin(), "(") 6300 << CodeModificationHint::CreateInsertion(EndLoc, ")"); 6301} 6302 6303/// DiagnoseBitwisePrecedence - Emit a warning when bitwise and comparison 6304/// operators are mixed in a way that suggests that the programmer forgot that 6305/// comparison operators have higher precedence. The most typical example of 6306/// such code is "flags & 0x0020 != 0", which is equivalent to "flags & 1". 6307static void DiagnoseBitwisePrecedence(Sema &Self, BinaryOperator::Opcode Opc, 6308 SourceLocation OpLoc,Expr *lhs,Expr *rhs){ 6309 typedef BinaryOperator BinOp; 6310 BinOp::Opcode lhsopc = static_cast<BinOp::Opcode>(-1), 6311 rhsopc = static_cast<BinOp::Opcode>(-1); 6312 if (BinOp *BO = dyn_cast<BinOp>(lhs)) 6313 lhsopc = BO->getOpcode(); 6314 if (BinOp *BO = dyn_cast<BinOp>(rhs)) 6315 rhsopc = BO->getOpcode(); 6316 6317 // Subs are not binary operators. 6318 if (lhsopc == -1 && rhsopc == -1) 6319 return; 6320 6321 // Bitwise operations are sometimes used as eager logical ops. 6322 // Don't diagnose this. 6323 if ((BinOp::isComparisonOp(lhsopc) || BinOp::isBitwiseOp(lhsopc)) && 6324 (BinOp::isComparisonOp(rhsopc) || BinOp::isBitwiseOp(rhsopc))) 6325 return; 6326 6327 if (BinOp::isComparisonOp(lhsopc)) 6328 SuggestParentheses(Self, OpLoc, 6329 PDiag(diag::warn_precedence_bitwise_rel) 6330 << SourceRange(lhs->getLocStart(), OpLoc) 6331 << BinOp::getOpcodeStr(Opc) << BinOp::getOpcodeStr(lhsopc), 6332 lhs->getSourceRange(), 6333 PDiag(diag::note_precedence_bitwise_first) 6334 << BinOp::getOpcodeStr(Opc), 6335 SourceRange(cast<BinOp>(lhs)->getRHS()->getLocStart(), rhs->getLocEnd())); 6336 else if (BinOp::isComparisonOp(rhsopc)) 6337 SuggestParentheses(Self, OpLoc, 6338 PDiag(diag::warn_precedence_bitwise_rel) 6339 << SourceRange(OpLoc, rhs->getLocEnd()) 6340 << BinOp::getOpcodeStr(Opc) << BinOp::getOpcodeStr(rhsopc), 6341 rhs->getSourceRange(), 6342 PDiag(diag::note_precedence_bitwise_first) 6343 << BinOp::getOpcodeStr(Opc), 6344 SourceRange(lhs->getLocEnd(), cast<BinOp>(rhs)->getLHS()->getLocStart())); 6345} 6346 6347/// DiagnoseBinOpPrecedence - Emit warnings for expressions with tricky 6348/// precedence. This currently diagnoses only "arg1 'bitwise' arg2 'eq' arg3". 6349/// But it could also warn about arg1 && arg2 || arg3, as GCC 4.3+ does. 6350static void DiagnoseBinOpPrecedence(Sema &Self, BinaryOperator::Opcode Opc, 6351 SourceLocation OpLoc, Expr *lhs, Expr *rhs){ 6352 if (BinaryOperator::isBitwiseOp(Opc)) 6353 DiagnoseBitwisePrecedence(Self, Opc, OpLoc, lhs, rhs); 6354} 6355 6356// Binary Operators. 'Tok' is the token for the operator. 6357Action::OwningExprResult Sema::ActOnBinOp(Scope *S, SourceLocation TokLoc, 6358 tok::TokenKind Kind, 6359 ExprArg LHS, ExprArg RHS) { 6360 BinaryOperator::Opcode Opc = ConvertTokenKindToBinaryOpcode(Kind); 6361 Expr *lhs = LHS.takeAs<Expr>(), *rhs = RHS.takeAs<Expr>(); 6362 6363 assert((lhs != 0) && "ActOnBinOp(): missing left expression"); 6364 assert((rhs != 0) && "ActOnBinOp(): missing right expression"); 6365 6366 // Emit warnings for tricky precedence issues, e.g. "bitfield & 0x4 == 0" 6367 DiagnoseBinOpPrecedence(*this, Opc, TokLoc, lhs, rhs); 6368 6369 return BuildBinOp(S, TokLoc, Opc, lhs, rhs); 6370} 6371 6372Action::OwningExprResult Sema::BuildBinOp(Scope *S, SourceLocation OpLoc, 6373 BinaryOperator::Opcode Opc, 6374 Expr *lhs, Expr *rhs) { 6375 if (getLangOptions().CPlusPlus && 6376 (lhs->getType()->isOverloadableType() || 6377 rhs->getType()->isOverloadableType())) { 6378 // Find all of the overloaded operators visible from this 6379 // point. We perform both an operator-name lookup from the local 6380 // scope and an argument-dependent lookup based on the types of 6381 // the arguments. 6382 UnresolvedSet<16> Functions; 6383 OverloadedOperatorKind OverOp = BinaryOperator::getOverloadedOperator(Opc); 6384 if (S && OverOp != OO_None) 6385 LookupOverloadedOperatorName(OverOp, S, lhs->getType(), rhs->getType(), 6386 Functions); 6387 6388 // Build the (potentially-overloaded, potentially-dependent) 6389 // binary operation. 6390 return CreateOverloadedBinOp(OpLoc, Opc, Functions, lhs, rhs); 6391 } 6392 6393 // Build a built-in binary operation. 6394 return CreateBuiltinBinOp(OpLoc, Opc, lhs, rhs); 6395} 6396 6397Action::OwningExprResult Sema::CreateBuiltinUnaryOp(SourceLocation OpLoc, 6398 unsigned OpcIn, 6399 ExprArg InputArg) { 6400 UnaryOperator::Opcode Opc = static_cast<UnaryOperator::Opcode>(OpcIn); 6401 6402 // FIXME: Input is modified below, but InputArg is not updated appropriately. 6403 Expr *Input = (Expr *)InputArg.get(); 6404 QualType resultType; 6405 switch (Opc) { 6406 case UnaryOperator::OffsetOf: 6407 assert(false && "Invalid unary operator"); 6408 break; 6409 6410 case UnaryOperator::PreInc: 6411 case UnaryOperator::PreDec: 6412 case UnaryOperator::PostInc: 6413 case UnaryOperator::PostDec: 6414 resultType = CheckIncrementDecrementOperand(Input, OpLoc, 6415 Opc == UnaryOperator::PreInc || 6416 Opc == UnaryOperator::PostInc); 6417 break; 6418 case UnaryOperator::AddrOf: 6419 resultType = CheckAddressOfOperand(Input, OpLoc); 6420 break; 6421 case UnaryOperator::Deref: 6422 DefaultFunctionArrayLvalueConversion(Input); 6423 resultType = CheckIndirectionOperand(Input, OpLoc); 6424 break; 6425 case UnaryOperator::Plus: 6426 case UnaryOperator::Minus: 6427 UsualUnaryConversions(Input); 6428 resultType = Input->getType(); 6429 if (resultType->isDependentType()) 6430 break; 6431 if (resultType->isArithmeticType()) // C99 6.5.3.3p1 6432 break; 6433 else if (getLangOptions().CPlusPlus && // C++ [expr.unary.op]p6-7 6434 resultType->isEnumeralType()) 6435 break; 6436 else if (getLangOptions().CPlusPlus && // C++ [expr.unary.op]p6 6437 Opc == UnaryOperator::Plus && 6438 resultType->isPointerType()) 6439 break; 6440 6441 return ExprError(Diag(OpLoc, diag::err_typecheck_unary_expr) 6442 << resultType << Input->getSourceRange()); 6443 case UnaryOperator::Not: // bitwise complement 6444 UsualUnaryConversions(Input); 6445 resultType = Input->getType(); 6446 if (resultType->isDependentType()) 6447 break; 6448 // C99 6.5.3.3p1. We allow complex int and float as a GCC extension. 6449 if (resultType->isComplexType() || resultType->isComplexIntegerType()) 6450 // C99 does not support '~' for complex conjugation. 6451 Diag(OpLoc, diag::ext_integer_complement_complex) 6452 << resultType << Input->getSourceRange(); 6453 else if (!resultType->isIntegerType()) 6454 return ExprError(Diag(OpLoc, diag::err_typecheck_unary_expr) 6455 << resultType << Input->getSourceRange()); 6456 break; 6457 case UnaryOperator::LNot: // logical negation 6458 // Unlike +/-/~, integer promotions aren't done here (C99 6.5.3.3p5). 6459 DefaultFunctionArrayLvalueConversion(Input); 6460 resultType = Input->getType(); 6461 if (resultType->isDependentType()) 6462 break; 6463 if (!resultType->isScalarType()) // C99 6.5.3.3p1 6464 return ExprError(Diag(OpLoc, diag::err_typecheck_unary_expr) 6465 << resultType << Input->getSourceRange()); 6466 // LNot always has type int. C99 6.5.3.3p5. 6467 // In C++, it's bool. C++ 5.3.1p8 6468 resultType = getLangOptions().CPlusPlus ? Context.BoolTy : Context.IntTy; 6469 break; 6470 case UnaryOperator::Real: 6471 case UnaryOperator::Imag: 6472 resultType = CheckRealImagOperand(Input, OpLoc, Opc == UnaryOperator::Real); 6473 break; 6474 case UnaryOperator::Extension: 6475 resultType = Input->getType(); 6476 break; 6477 } 6478 if (resultType.isNull()) 6479 return ExprError(); 6480 6481 InputArg.release(); 6482 return Owned(new (Context) UnaryOperator(Input, Opc, resultType, OpLoc)); 6483} 6484 6485Action::OwningExprResult Sema::BuildUnaryOp(Scope *S, SourceLocation OpLoc, 6486 UnaryOperator::Opcode Opc, 6487 ExprArg input) { 6488 Expr *Input = (Expr*)input.get(); 6489 if (getLangOptions().CPlusPlus && Input->getType()->isOverloadableType() && 6490 Opc != UnaryOperator::Extension) { 6491 // Find all of the overloaded operators visible from this 6492 // point. We perform both an operator-name lookup from the local 6493 // scope and an argument-dependent lookup based on the types of 6494 // the arguments. 6495 UnresolvedSet<16> Functions; 6496 OverloadedOperatorKind OverOp = UnaryOperator::getOverloadedOperator(Opc); 6497 if (S && OverOp != OO_None) 6498 LookupOverloadedOperatorName(OverOp, S, Input->getType(), QualType(), 6499 Functions); 6500 6501 return CreateOverloadedUnaryOp(OpLoc, Opc, Functions, move(input)); 6502 } 6503 6504 return CreateBuiltinUnaryOp(OpLoc, Opc, move(input)); 6505} 6506 6507// Unary Operators. 'Tok' is the token for the operator. 6508Action::OwningExprResult Sema::ActOnUnaryOp(Scope *S, SourceLocation OpLoc, 6509 tok::TokenKind Op, ExprArg input) { 6510 return BuildUnaryOp(S, OpLoc, ConvertTokenKindToUnaryOpcode(Op), move(input)); 6511} 6512 6513/// ActOnAddrLabel - Parse the GNU address of label extension: "&&foo". 6514Sema::OwningExprResult Sema::ActOnAddrLabel(SourceLocation OpLoc, 6515 SourceLocation LabLoc, 6516 IdentifierInfo *LabelII) { 6517 // Look up the record for this label identifier. 6518 LabelStmt *&LabelDecl = getLabelMap()[LabelII]; 6519 6520 // If we haven't seen this label yet, create a forward reference. It 6521 // will be validated and/or cleaned up in ActOnFinishFunctionBody. 6522 if (LabelDecl == 0) 6523 LabelDecl = new (Context) LabelStmt(LabLoc, LabelII, 0); 6524 6525 // Create the AST node. The address of a label always has type 'void*'. 6526 return Owned(new (Context) AddrLabelExpr(OpLoc, LabLoc, LabelDecl, 6527 Context.getPointerType(Context.VoidTy))); 6528} 6529 6530Sema::OwningExprResult 6531Sema::ActOnStmtExpr(SourceLocation LPLoc, StmtArg substmt, 6532 SourceLocation RPLoc) { // "({..})" 6533 Stmt *SubStmt = static_cast<Stmt*>(substmt.get()); 6534 assert(SubStmt && isa<CompoundStmt>(SubStmt) && "Invalid action invocation!"); 6535 CompoundStmt *Compound = cast<CompoundStmt>(SubStmt); 6536 6537 bool isFileScope = getCurFunctionOrMethodDecl() == 0; 6538 if (isFileScope) 6539 return ExprError(Diag(LPLoc, diag::err_stmtexpr_file_scope)); 6540 6541 // FIXME: there are a variety of strange constraints to enforce here, for 6542 // example, it is not possible to goto into a stmt expression apparently. 6543 // More semantic analysis is needed. 6544 6545 // If there are sub stmts in the compound stmt, take the type of the last one 6546 // as the type of the stmtexpr. 6547 QualType Ty = Context.VoidTy; 6548 6549 if (!Compound->body_empty()) { 6550 Stmt *LastStmt = Compound->body_back(); 6551 // If LastStmt is a label, skip down through into the body. 6552 while (LabelStmt *Label = dyn_cast<LabelStmt>(LastStmt)) 6553 LastStmt = Label->getSubStmt(); 6554 6555 if (Expr *LastExpr = dyn_cast<Expr>(LastStmt)) 6556 Ty = LastExpr->getType(); 6557 } 6558 6559 // FIXME: Check that expression type is complete/non-abstract; statement 6560 // expressions are not lvalues. 6561 6562 substmt.release(); 6563 return Owned(new (Context) StmtExpr(Compound, Ty, LPLoc, RPLoc)); 6564} 6565 6566Sema::OwningExprResult Sema::ActOnBuiltinOffsetOf(Scope *S, 6567 SourceLocation BuiltinLoc, 6568 SourceLocation TypeLoc, 6569 TypeTy *argty, 6570 OffsetOfComponent *CompPtr, 6571 unsigned NumComponents, 6572 SourceLocation RPLoc) { 6573 // FIXME: This function leaks all expressions in the offset components on 6574 // error. 6575 // FIXME: Preserve type source info. 6576 QualType ArgTy = GetTypeFromParser(argty); 6577 assert(!ArgTy.isNull() && "Missing type argument!"); 6578 6579 bool Dependent = ArgTy->isDependentType(); 6580 6581 // We must have at least one component that refers to the type, and the first 6582 // one is known to be a field designator. Verify that the ArgTy represents 6583 // a struct/union/class. 6584 if (!Dependent && !ArgTy->isRecordType()) 6585 return ExprError(Diag(TypeLoc, diag::err_offsetof_record_type) << ArgTy); 6586 6587 // FIXME: Type must be complete per C99 7.17p3 because a declaring a variable 6588 // with an incomplete type would be illegal. 6589 6590 // Otherwise, create a null pointer as the base, and iteratively process 6591 // the offsetof designators. 6592 QualType ArgTyPtr = Context.getPointerType(ArgTy); 6593 Expr* Res = new (Context) ImplicitValueInitExpr(ArgTyPtr); 6594 Res = new (Context) UnaryOperator(Res, UnaryOperator::Deref, 6595 ArgTy, SourceLocation()); 6596 6597 // offsetof with non-identifier designators (e.g. "offsetof(x, a.b[c])") are a 6598 // GCC extension, diagnose them. 6599 // FIXME: This diagnostic isn't actually visible because the location is in 6600 // a system header! 6601 if (NumComponents != 1) 6602 Diag(BuiltinLoc, diag::ext_offsetof_extended_field_designator) 6603 << SourceRange(CompPtr[1].LocStart, CompPtr[NumComponents-1].LocEnd); 6604 6605 if (!Dependent) { 6606 bool DidWarnAboutNonPOD = false; 6607 6608 if (RequireCompleteType(TypeLoc, Res->getType(), 6609 diag::err_offsetof_incomplete_type)) 6610 return ExprError(); 6611 6612 // FIXME: Dependent case loses a lot of information here. And probably 6613 // leaks like a sieve. 6614 for (unsigned i = 0; i != NumComponents; ++i) { 6615 const OffsetOfComponent &OC = CompPtr[i]; 6616 if (OC.isBrackets) { 6617 // Offset of an array sub-field. TODO: Should we allow vector elements? 6618 const ArrayType *AT = Context.getAsArrayType(Res->getType()); 6619 if (!AT) { 6620 Res->Destroy(Context); 6621 return ExprError(Diag(OC.LocEnd, diag::err_offsetof_array_type) 6622 << Res->getType()); 6623 } 6624 6625 // FIXME: C++: Verify that operator[] isn't overloaded. 6626 6627 // Promote the array so it looks more like a normal array subscript 6628 // expression. 6629 DefaultFunctionArrayLvalueConversion(Res); 6630 6631 // C99 6.5.2.1p1 6632 Expr *Idx = static_cast<Expr*>(OC.U.E); 6633 // FIXME: Leaks Res 6634 if (!Idx->isTypeDependent() && !Idx->getType()->isIntegerType()) 6635 return ExprError(Diag(Idx->getLocStart(), 6636 diag::err_typecheck_subscript_not_integer) 6637 << Idx->getSourceRange()); 6638 6639 Res = new (Context) ArraySubscriptExpr(Res, Idx, AT->getElementType(), 6640 OC.LocEnd); 6641 continue; 6642 } 6643 6644 const RecordType *RC = Res->getType()->getAs<RecordType>(); 6645 if (!RC) { 6646 Res->Destroy(Context); 6647 return ExprError(Diag(OC.LocEnd, diag::err_offsetof_record_type) 6648 << Res->getType()); 6649 } 6650 6651 // Get the decl corresponding to this. 6652 RecordDecl *RD = RC->getDecl(); 6653 if (CXXRecordDecl *CRD = dyn_cast<CXXRecordDecl>(RD)) { 6654 if (!CRD->isPOD() && !DidWarnAboutNonPOD && 6655 DiagRuntimeBehavior(BuiltinLoc, 6656 PDiag(diag::warn_offsetof_non_pod_type) 6657 << SourceRange(CompPtr[0].LocStart, OC.LocEnd) 6658 << Res->getType())) 6659 DidWarnAboutNonPOD = true; 6660 } 6661 6662 LookupResult R(*this, OC.U.IdentInfo, OC.LocStart, LookupMemberName); 6663 LookupQualifiedName(R, RD); 6664 6665 FieldDecl *MemberDecl = R.getAsSingle<FieldDecl>(); 6666 // FIXME: Leaks Res 6667 if (!MemberDecl) 6668 return ExprError(Diag(BuiltinLoc, diag::err_no_member) 6669 << OC.U.IdentInfo << RD << SourceRange(OC.LocStart, OC.LocEnd)); 6670 6671 // FIXME: C++: Verify that MemberDecl isn't a static field. 6672 // FIXME: Verify that MemberDecl isn't a bitfield. 6673 if (cast<RecordDecl>(MemberDecl->getDeclContext())->isAnonymousStructOrUnion()) { 6674 Res = BuildAnonymousStructUnionMemberReference( 6675 OC.LocEnd, MemberDecl, Res, OC.LocEnd).takeAs<Expr>(); 6676 } else { 6677 PerformObjectMemberConversion(Res, MemberDecl); 6678 // MemberDecl->getType() doesn't get the right qualifiers, but it 6679 // doesn't matter here. 6680 Res = new (Context) MemberExpr(Res, false, MemberDecl, OC.LocEnd, 6681 MemberDecl->getType().getNonReferenceType()); 6682 } 6683 } 6684 } 6685 6686 return Owned(new (Context) UnaryOperator(Res, UnaryOperator::OffsetOf, 6687 Context.getSizeType(), BuiltinLoc)); 6688} 6689 6690 6691Sema::OwningExprResult Sema::ActOnTypesCompatibleExpr(SourceLocation BuiltinLoc, 6692 TypeTy *arg1,TypeTy *arg2, 6693 SourceLocation RPLoc) { 6694 // FIXME: Preserve type source info. 6695 QualType argT1 = GetTypeFromParser(arg1); 6696 QualType argT2 = GetTypeFromParser(arg2); 6697 6698 assert((!argT1.isNull() && !argT2.isNull()) && "Missing type argument(s)"); 6699 6700 if (getLangOptions().CPlusPlus) { 6701 Diag(BuiltinLoc, diag::err_types_compatible_p_in_cplusplus) 6702 << SourceRange(BuiltinLoc, RPLoc); 6703 return ExprError(); 6704 } 6705 6706 return Owned(new (Context) TypesCompatibleExpr(Context.IntTy, BuiltinLoc, 6707 argT1, argT2, RPLoc)); 6708} 6709 6710Sema::OwningExprResult Sema::ActOnChooseExpr(SourceLocation BuiltinLoc, 6711 ExprArg cond, 6712 ExprArg expr1, ExprArg expr2, 6713 SourceLocation RPLoc) { 6714 Expr *CondExpr = static_cast<Expr*>(cond.get()); 6715 Expr *LHSExpr = static_cast<Expr*>(expr1.get()); 6716 Expr *RHSExpr = static_cast<Expr*>(expr2.get()); 6717 6718 assert((CondExpr && LHSExpr && RHSExpr) && "Missing type argument(s)"); 6719 6720 QualType resType; 6721 bool ValueDependent = false; 6722 if (CondExpr->isTypeDependent() || CondExpr->isValueDependent()) { 6723 resType = Context.DependentTy; 6724 ValueDependent = true; 6725 } else { 6726 // The conditional expression is required to be a constant expression. 6727 llvm::APSInt condEval(32); 6728 SourceLocation ExpLoc; 6729 if (!CondExpr->isIntegerConstantExpr(condEval, Context, &ExpLoc)) 6730 return ExprError(Diag(ExpLoc, 6731 diag::err_typecheck_choose_expr_requires_constant) 6732 << CondExpr->getSourceRange()); 6733 6734 // If the condition is > zero, then the AST type is the same as the LSHExpr. 6735 resType = condEval.getZExtValue() ? LHSExpr->getType() : RHSExpr->getType(); 6736 ValueDependent = condEval.getZExtValue() ? LHSExpr->isValueDependent() 6737 : RHSExpr->isValueDependent(); 6738 } 6739 6740 cond.release(); expr1.release(); expr2.release(); 6741 return Owned(new (Context) ChooseExpr(BuiltinLoc, CondExpr, LHSExpr, RHSExpr, 6742 resType, RPLoc, 6743 resType->isDependentType(), 6744 ValueDependent)); 6745} 6746 6747//===----------------------------------------------------------------------===// 6748// Clang Extensions. 6749//===----------------------------------------------------------------------===// 6750 6751/// ActOnBlockStart - This callback is invoked when a block literal is started. 6752void Sema::ActOnBlockStart(SourceLocation CaretLoc, Scope *BlockScope) { 6753 // Analyze block parameters. 6754 BlockSemaInfo *BSI = new BlockSemaInfo(); 6755 6756 // Add BSI to CurBlock. 6757 BSI->PrevBlockInfo = CurBlock; 6758 CurBlock = BSI; 6759 6760 BSI->ReturnType = QualType(); 6761 BSI->TheScope = BlockScope; 6762 BSI->hasBlockDeclRefExprs = false; 6763 BSI->hasPrototype = false; 6764 BSI->SavedFunctionNeedsScopeChecking = CurFunctionNeedsScopeChecking; 6765 CurFunctionNeedsScopeChecking = false; 6766 6767 BSI->TheDecl = BlockDecl::Create(Context, CurContext, CaretLoc); 6768 CurContext->addDecl(BSI->TheDecl); 6769 PushDeclContext(BlockScope, BSI->TheDecl); 6770} 6771 6772void Sema::ActOnBlockArguments(Declarator &ParamInfo, Scope *CurScope) { 6773 assert(ParamInfo.getIdentifier()==0 && "block-id should have no identifier!"); 6774 6775 if (ParamInfo.getNumTypeObjects() == 0 6776 || ParamInfo.getTypeObject(0).Kind != DeclaratorChunk::Function) { 6777 ProcessDeclAttributes(CurScope, CurBlock->TheDecl, ParamInfo); 6778 QualType T = GetTypeForDeclarator(ParamInfo, CurScope); 6779 6780 if (T->isArrayType()) { 6781 Diag(ParamInfo.getSourceRange().getBegin(), 6782 diag::err_block_returns_array); 6783 return; 6784 } 6785 6786 // The parameter list is optional, if there was none, assume (). 6787 if (!T->isFunctionType()) 6788 T = Context.getFunctionType(T, 0, 0, false, 0, false, false, 0, 0, false, 6789 CC_Default); 6790 6791 CurBlock->hasPrototype = true; 6792 CurBlock->isVariadic = false; 6793 // Check for a valid sentinel attribute on this block. 6794 if (CurBlock->TheDecl->getAttr<SentinelAttr>()) { 6795 Diag(ParamInfo.getAttributes()->getLoc(), 6796 diag::warn_attribute_sentinel_not_variadic) << 1; 6797 // FIXME: remove the attribute. 6798 } 6799 QualType RetTy = T.getTypePtr()->getAs<FunctionType>()->getResultType(); 6800 6801 // Do not allow returning a objc interface by-value. 6802 if (RetTy->isObjCInterfaceType()) { 6803 Diag(ParamInfo.getSourceRange().getBegin(), 6804 diag::err_object_cannot_be_passed_returned_by_value) << 0 << RetTy; 6805 return; 6806 } 6807 6808 CurBlock->ReturnType = RetTy; 6809 return; 6810 } 6811 6812 // Analyze arguments to block. 6813 assert(ParamInfo.getTypeObject(0).Kind == DeclaratorChunk::Function && 6814 "Not a function declarator!"); 6815 DeclaratorChunk::FunctionTypeInfo &FTI = ParamInfo.getTypeObject(0).Fun; 6816 6817 CurBlock->hasPrototype = FTI.hasPrototype; 6818 CurBlock->isVariadic = true; 6819 6820 // Check for C99 6.7.5.3p10 - foo(void) is a non-varargs function that takes 6821 // no arguments, not a function that takes a single void argument. 6822 if (FTI.hasPrototype && 6823 FTI.NumArgs == 1 && !FTI.isVariadic && FTI.ArgInfo[0].Ident == 0 && 6824 (!FTI.ArgInfo[0].Param.getAs<ParmVarDecl>()->getType().getCVRQualifiers()&& 6825 FTI.ArgInfo[0].Param.getAs<ParmVarDecl>()->getType()->isVoidType())) { 6826 // empty arg list, don't push any params. 6827 CurBlock->isVariadic = false; 6828 } else if (FTI.hasPrototype) { 6829 for (unsigned i = 0, e = FTI.NumArgs; i != e; ++i) { 6830 ParmVarDecl *Param = FTI.ArgInfo[i].Param.getAs<ParmVarDecl>(); 6831 if (Param->getIdentifier() == 0 && 6832 !Param->isImplicit() && 6833 !Param->isInvalidDecl() && 6834 !getLangOptions().CPlusPlus) 6835 Diag(Param->getLocation(), diag::err_parameter_name_omitted); 6836 CurBlock->Params.push_back(Param); 6837 } 6838 CurBlock->isVariadic = FTI.isVariadic; 6839 } 6840 CurBlock->TheDecl->setParams(CurBlock->Params.data(), 6841 CurBlock->Params.size()); 6842 CurBlock->TheDecl->setIsVariadic(CurBlock->isVariadic); 6843 ProcessDeclAttributes(CurScope, CurBlock->TheDecl, ParamInfo); 6844 for (BlockDecl::param_iterator AI = CurBlock->TheDecl->param_begin(), 6845 E = CurBlock->TheDecl->param_end(); AI != E; ++AI) { 6846 (*AI)->setOwningFunction(CurBlock->TheDecl); 6847 6848 // If this has an identifier, add it to the scope stack. 6849 if ((*AI)->getIdentifier()) 6850 PushOnScopeChains(*AI, CurBlock->TheScope); 6851 } 6852 6853 // Check for a valid sentinel attribute on this block. 6854 if (!CurBlock->isVariadic && 6855 CurBlock->TheDecl->getAttr<SentinelAttr>()) { 6856 Diag(ParamInfo.getAttributes()->getLoc(), 6857 diag::warn_attribute_sentinel_not_variadic) << 1; 6858 // FIXME: remove the attribute. 6859 } 6860 6861 // Analyze the return type. 6862 QualType T = GetTypeForDeclarator(ParamInfo, CurScope); 6863 QualType RetTy = T->getAs<FunctionType>()->getResultType(); 6864 6865 // Do not allow returning a objc interface by-value. 6866 if (RetTy->isObjCInterfaceType()) { 6867 Diag(ParamInfo.getSourceRange().getBegin(), 6868 diag::err_object_cannot_be_passed_returned_by_value) << 0 << RetTy; 6869 } else if (!RetTy->isDependentType()) 6870 CurBlock->ReturnType = RetTy; 6871} 6872 6873/// ActOnBlockError - If there is an error parsing a block, this callback 6874/// is invoked to pop the information about the block from the action impl. 6875void Sema::ActOnBlockError(SourceLocation CaretLoc, Scope *CurScope) { 6876 // Ensure that CurBlock is deleted. 6877 llvm::OwningPtr<BlockSemaInfo> CC(CurBlock); 6878 6879 CurFunctionNeedsScopeChecking = CurBlock->SavedFunctionNeedsScopeChecking; 6880 6881 // Pop off CurBlock, handle nested blocks. 6882 PopDeclContext(); 6883 CurBlock = CurBlock->PrevBlockInfo; 6884 // FIXME: Delete the ParmVarDecl objects as well??? 6885} 6886 6887/// ActOnBlockStmtExpr - This is called when the body of a block statement 6888/// literal was successfully completed. ^(int x){...} 6889Sema::OwningExprResult Sema::ActOnBlockStmtExpr(SourceLocation CaretLoc, 6890 StmtArg body, Scope *CurScope) { 6891 // If blocks are disabled, emit an error. 6892 if (!LangOpts.Blocks) 6893 Diag(CaretLoc, diag::err_blocks_disable); 6894 6895 // Ensure that CurBlock is deleted. 6896 llvm::OwningPtr<BlockSemaInfo> BSI(CurBlock); 6897 6898 PopDeclContext(); 6899 6900 // Pop off CurBlock, handle nested blocks. 6901 CurBlock = CurBlock->PrevBlockInfo; 6902 6903 QualType RetTy = Context.VoidTy; 6904 if (!BSI->ReturnType.isNull()) 6905 RetTy = BSI->ReturnType; 6906 6907 llvm::SmallVector<QualType, 8> ArgTypes; 6908 for (unsigned i = 0, e = BSI->Params.size(); i != e; ++i) 6909 ArgTypes.push_back(BSI->Params[i]->getType()); 6910 6911 bool NoReturn = BSI->TheDecl->getAttr<NoReturnAttr>(); 6912 QualType BlockTy; 6913 if (!BSI->hasPrototype) 6914 BlockTy = Context.getFunctionType(RetTy, 0, 0, false, 0, false, false, 0, 0, 6915 NoReturn, CC_Default); 6916 else 6917 BlockTy = Context.getFunctionType(RetTy, ArgTypes.data(), ArgTypes.size(), 6918 BSI->isVariadic, 0, false, false, 0, 0, 6919 NoReturn, CC_Default); 6920 6921 // FIXME: Check that return/parameter types are complete/non-abstract 6922 DiagnoseUnusedParameters(BSI->Params.begin(), BSI->Params.end()); 6923 BlockTy = Context.getBlockPointerType(BlockTy); 6924 6925 // If needed, diagnose invalid gotos and switches in the block. 6926 if (CurFunctionNeedsScopeChecking) 6927 DiagnoseInvalidJumps(static_cast<CompoundStmt*>(body.get())); 6928 CurFunctionNeedsScopeChecking = BSI->SavedFunctionNeedsScopeChecking; 6929 6930 BSI->TheDecl->setBody(body.takeAs<CompoundStmt>()); 6931 6932 bool Good = true; 6933 // Check goto/label use. 6934 for (llvm::DenseMap<IdentifierInfo*, LabelStmt*>::iterator 6935 I = BSI->LabelMap.begin(), E = BSI->LabelMap.end(); I != E; ++I) { 6936 LabelStmt *L = I->second; 6937 6938 // Verify that we have no forward references left. If so, there was a goto 6939 // or address of a label taken, but no definition of it. 6940 if (L->getSubStmt() != 0) 6941 continue; 6942 6943 // Emit error. 6944 Diag(L->getIdentLoc(), diag::err_undeclared_label_use) << L->getName(); 6945 Good = false; 6946 } 6947 BSI->LabelMap.clear(); 6948 if (!Good) 6949 return ExprError(); 6950 6951 AnalysisContext AC(BSI->TheDecl); 6952 CheckFallThroughForBlock(BlockTy, BSI->TheDecl->getBody(), AC); 6953 CheckUnreachable(AC); 6954 return Owned(new (Context) BlockExpr(BSI->TheDecl, BlockTy, 6955 BSI->hasBlockDeclRefExprs)); 6956} 6957 6958Sema::OwningExprResult Sema::ActOnVAArg(SourceLocation BuiltinLoc, 6959 ExprArg expr, TypeTy *type, 6960 SourceLocation RPLoc) { 6961 QualType T = GetTypeFromParser(type); 6962 Expr *E = static_cast<Expr*>(expr.get()); 6963 Expr *OrigExpr = E; 6964 6965 InitBuiltinVaListType(); 6966 6967 // Get the va_list type 6968 QualType VaListType = Context.getBuiltinVaListType(); 6969 if (VaListType->isArrayType()) { 6970 // Deal with implicit array decay; for example, on x86-64, 6971 // va_list is an array, but it's supposed to decay to 6972 // a pointer for va_arg. 6973 VaListType = Context.getArrayDecayedType(VaListType); 6974 // Make sure the input expression also decays appropriately. 6975 UsualUnaryConversions(E); 6976 } else { 6977 // Otherwise, the va_list argument must be an l-value because 6978 // it is modified by va_arg. 6979 if (!E->isTypeDependent() && 6980 CheckForModifiableLvalue(E, BuiltinLoc, *this)) 6981 return ExprError(); 6982 } 6983 6984 if (!E->isTypeDependent() && 6985 !Context.hasSameType(VaListType, E->getType())) { 6986 return ExprError(Diag(E->getLocStart(), 6987 diag::err_first_argument_to_va_arg_not_of_type_va_list) 6988 << OrigExpr->getType() << E->getSourceRange()); 6989 } 6990 6991 // FIXME: Check that type is complete/non-abstract 6992 // FIXME: Warn if a non-POD type is passed in. 6993 6994 expr.release(); 6995 return Owned(new (Context) VAArgExpr(BuiltinLoc, E, T.getNonReferenceType(), 6996 RPLoc)); 6997} 6998 6999Sema::OwningExprResult Sema::ActOnGNUNullExpr(SourceLocation TokenLoc) { 7000 // The type of __null will be int or long, depending on the size of 7001 // pointers on the target. 7002 QualType Ty; 7003 if (Context.Target.getPointerWidth(0) == Context.Target.getIntWidth()) 7004 Ty = Context.IntTy; 7005 else 7006 Ty = Context.LongTy; 7007 7008 return Owned(new (Context) GNUNullExpr(Ty, TokenLoc)); 7009} 7010 7011static void 7012MakeObjCStringLiteralCodeModificationHint(Sema& SemaRef, 7013 QualType DstType, 7014 Expr *SrcExpr, 7015 CodeModificationHint &Hint) { 7016 if (!SemaRef.getLangOptions().ObjC1) 7017 return; 7018 7019 const ObjCObjectPointerType *PT = DstType->getAs<ObjCObjectPointerType>(); 7020 if (!PT) 7021 return; 7022 7023 // Check if the destination is of type 'id'. 7024 if (!PT->isObjCIdType()) { 7025 // Check if the destination is the 'NSString' interface. 7026 const ObjCInterfaceDecl *ID = PT->getInterfaceDecl(); 7027 if (!ID || !ID->getIdentifier()->isStr("NSString")) 7028 return; 7029 } 7030 7031 // Strip off any parens and casts. 7032 StringLiteral *SL = dyn_cast<StringLiteral>(SrcExpr->IgnoreParenCasts()); 7033 if (!SL || SL->isWide()) 7034 return; 7035 7036 Hint = CodeModificationHint::CreateInsertion(SL->getLocStart(), "@"); 7037} 7038 7039bool Sema::DiagnoseAssignmentResult(AssignConvertType ConvTy, 7040 SourceLocation Loc, 7041 QualType DstType, QualType SrcType, 7042 Expr *SrcExpr, AssignmentAction Action) { 7043 // Decode the result (notice that AST's are still created for extensions). 7044 bool isInvalid = false; 7045 unsigned DiagKind; 7046 CodeModificationHint Hint; 7047 7048 switch (ConvTy) { 7049 default: assert(0 && "Unknown conversion type"); 7050 case Compatible: return false; 7051 case PointerToInt: 7052 DiagKind = diag::ext_typecheck_convert_pointer_int; 7053 break; 7054 case IntToPointer: 7055 DiagKind = diag::ext_typecheck_convert_int_pointer; 7056 break; 7057 case IncompatiblePointer: 7058 MakeObjCStringLiteralCodeModificationHint(*this, DstType, SrcExpr, Hint); 7059 DiagKind = diag::ext_typecheck_convert_incompatible_pointer; 7060 break; 7061 case IncompatiblePointerSign: 7062 DiagKind = diag::ext_typecheck_convert_incompatible_pointer_sign; 7063 break; 7064 case FunctionVoidPointer: 7065 DiagKind = diag::ext_typecheck_convert_pointer_void_func; 7066 break; 7067 case CompatiblePointerDiscardsQualifiers: 7068 // If the qualifiers lost were because we were applying the 7069 // (deprecated) C++ conversion from a string literal to a char* 7070 // (or wchar_t*), then there was no error (C++ 4.2p2). FIXME: 7071 // Ideally, this check would be performed in 7072 // CheckPointerTypesForAssignment. However, that would require a 7073 // bit of refactoring (so that the second argument is an 7074 // expression, rather than a type), which should be done as part 7075 // of a larger effort to fix CheckPointerTypesForAssignment for 7076 // C++ semantics. 7077 if (getLangOptions().CPlusPlus && 7078 IsStringLiteralToNonConstPointerConversion(SrcExpr, DstType)) 7079 return false; 7080 DiagKind = diag::ext_typecheck_convert_discards_qualifiers; 7081 break; 7082 case IncompatibleNestedPointerQualifiers: 7083 DiagKind = diag::ext_nested_pointer_qualifier_mismatch; 7084 break; 7085 case IntToBlockPointer: 7086 DiagKind = diag::err_int_to_block_pointer; 7087 break; 7088 case IncompatibleBlockPointer: 7089 DiagKind = diag::err_typecheck_convert_incompatible_block_pointer; 7090 break; 7091 case IncompatibleObjCQualifiedId: 7092 // FIXME: Diagnose the problem in ObjCQualifiedIdTypesAreCompatible, since 7093 // it can give a more specific diagnostic. 7094 DiagKind = diag::warn_incompatible_qualified_id; 7095 break; 7096 case IncompatibleVectors: 7097 DiagKind = diag::warn_incompatible_vectors; 7098 break; 7099 case Incompatible: 7100 DiagKind = diag::err_typecheck_convert_incompatible; 7101 isInvalid = true; 7102 break; 7103 } 7104 7105 Diag(Loc, DiagKind) << DstType << SrcType << Action 7106 << SrcExpr->getSourceRange() << Hint; 7107 return isInvalid; 7108} 7109 7110bool Sema::VerifyIntegerConstantExpression(const Expr *E, llvm::APSInt *Result){ 7111 llvm::APSInt ICEResult; 7112 if (E->isIntegerConstantExpr(ICEResult, Context)) { 7113 if (Result) 7114 *Result = ICEResult; 7115 return false; 7116 } 7117 7118 Expr::EvalResult EvalResult; 7119 7120 if (!E->Evaluate(EvalResult, Context) || !EvalResult.Val.isInt() || 7121 EvalResult.HasSideEffects) { 7122 Diag(E->getExprLoc(), diag::err_expr_not_ice) << E->getSourceRange(); 7123 7124 if (EvalResult.Diag) { 7125 // We only show the note if it's not the usual "invalid subexpression" 7126 // or if it's actually in a subexpression. 7127 if (EvalResult.Diag != diag::note_invalid_subexpr_in_ice || 7128 E->IgnoreParens() != EvalResult.DiagExpr->IgnoreParens()) 7129 Diag(EvalResult.DiagLoc, EvalResult.Diag); 7130 } 7131 7132 return true; 7133 } 7134 7135 Diag(E->getExprLoc(), diag::ext_expr_not_ice) << 7136 E->getSourceRange(); 7137 7138 if (EvalResult.Diag && 7139 Diags.getDiagnosticLevel(diag::ext_expr_not_ice) != Diagnostic::Ignored) 7140 Diag(EvalResult.DiagLoc, EvalResult.Diag); 7141 7142 if (Result) 7143 *Result = EvalResult.Val.getInt(); 7144 return false; 7145} 7146 7147void 7148Sema::PushExpressionEvaluationContext(ExpressionEvaluationContext NewContext) { 7149 ExprEvalContexts.push_back( 7150 ExpressionEvaluationContextRecord(NewContext, ExprTemporaries.size())); 7151} 7152 7153void 7154Sema::PopExpressionEvaluationContext() { 7155 // Pop the current expression evaluation context off the stack. 7156 ExpressionEvaluationContextRecord Rec = ExprEvalContexts.back(); 7157 ExprEvalContexts.pop_back(); 7158 7159 if (Rec.Context == PotentiallyPotentiallyEvaluated) { 7160 if (Rec.PotentiallyReferenced) { 7161 // Mark any remaining declarations in the current position of the stack 7162 // as "referenced". If they were not meant to be referenced, semantic 7163 // analysis would have eliminated them (e.g., in ActOnCXXTypeId). 7164 for (PotentiallyReferencedDecls::iterator 7165 I = Rec.PotentiallyReferenced->begin(), 7166 IEnd = Rec.PotentiallyReferenced->end(); 7167 I != IEnd; ++I) 7168 MarkDeclarationReferenced(I->first, I->second); 7169 } 7170 7171 if (Rec.PotentiallyDiagnosed) { 7172 // Emit any pending diagnostics. 7173 for (PotentiallyEmittedDiagnostics::iterator 7174 I = Rec.PotentiallyDiagnosed->begin(), 7175 IEnd = Rec.PotentiallyDiagnosed->end(); 7176 I != IEnd; ++I) 7177 Diag(I->first, I->second); 7178 } 7179 } 7180 7181 // When are coming out of an unevaluated context, clear out any 7182 // temporaries that we may have created as part of the evaluation of 7183 // the expression in that context: they aren't relevant because they 7184 // will never be constructed. 7185 if (Rec.Context == Unevaluated && 7186 ExprTemporaries.size() > Rec.NumTemporaries) 7187 ExprTemporaries.erase(ExprTemporaries.begin() + Rec.NumTemporaries, 7188 ExprTemporaries.end()); 7189 7190 // Destroy the popped expression evaluation record. 7191 Rec.Destroy(); 7192} 7193 7194/// \brief Note that the given declaration was referenced in the source code. 7195/// 7196/// This routine should be invoke whenever a given declaration is referenced 7197/// in the source code, and where that reference occurred. If this declaration 7198/// reference means that the the declaration is used (C++ [basic.def.odr]p2, 7199/// C99 6.9p3), then the declaration will be marked as used. 7200/// 7201/// \param Loc the location where the declaration was referenced. 7202/// 7203/// \param D the declaration that has been referenced by the source code. 7204void Sema::MarkDeclarationReferenced(SourceLocation Loc, Decl *D) { 7205 assert(D && "No declaration?"); 7206 7207 if (D->isUsed()) 7208 return; 7209 7210 // Mark a parameter or variable declaration "used", regardless of whether we're in a 7211 // template or not. The reason for this is that unevaluated expressions 7212 // (e.g. (void)sizeof()) constitute a use for warning purposes (-Wunused-variables and 7213 // -Wunused-parameters) 7214 if (isa<ParmVarDecl>(D) || 7215 (isa<VarDecl>(D) && D->getDeclContext()->isFunctionOrMethod())) 7216 D->setUsed(true); 7217 7218 // Do not mark anything as "used" within a dependent context; wait for 7219 // an instantiation. 7220 if (CurContext->isDependentContext()) 7221 return; 7222 7223 switch (ExprEvalContexts.back().Context) { 7224 case Unevaluated: 7225 // We are in an expression that is not potentially evaluated; do nothing. 7226 return; 7227 7228 case PotentiallyEvaluated: 7229 // We are in a potentially-evaluated expression, so this declaration is 7230 // "used"; handle this below. 7231 break; 7232 7233 case PotentiallyPotentiallyEvaluated: 7234 // We are in an expression that may be potentially evaluated; queue this 7235 // declaration reference until we know whether the expression is 7236 // potentially evaluated. 7237 ExprEvalContexts.back().addReferencedDecl(Loc, D); 7238 return; 7239 } 7240 7241 // Note that this declaration has been used. 7242 if (CXXConstructorDecl *Constructor = dyn_cast<CXXConstructorDecl>(D)) { 7243 unsigned TypeQuals; 7244 if (Constructor->isImplicit() && Constructor->isDefaultConstructor()) { 7245 if (!Constructor->isUsed()) 7246 DefineImplicitDefaultConstructor(Loc, Constructor); 7247 } else if (Constructor->isImplicit() && 7248 Constructor->isCopyConstructor(TypeQuals)) { 7249 if (!Constructor->isUsed()) 7250 DefineImplicitCopyConstructor(Loc, Constructor, TypeQuals); 7251 } 7252 7253 MaybeMarkVirtualMembersReferenced(Loc, Constructor); 7254 } else if (CXXDestructorDecl *Destructor = dyn_cast<CXXDestructorDecl>(D)) { 7255 if (Destructor->isImplicit() && !Destructor->isUsed()) 7256 DefineImplicitDestructor(Loc, Destructor); 7257 7258 } else if (CXXMethodDecl *MethodDecl = dyn_cast<CXXMethodDecl>(D)) { 7259 if (MethodDecl->isImplicit() && MethodDecl->isOverloadedOperator() && 7260 MethodDecl->getOverloadedOperator() == OO_Equal) { 7261 if (!MethodDecl->isUsed()) 7262 DefineImplicitOverloadedAssign(Loc, MethodDecl); 7263 } 7264 } 7265 if (FunctionDecl *Function = dyn_cast<FunctionDecl>(D)) { 7266 // Implicit instantiation of function templates and member functions of 7267 // class templates. 7268 if (!Function->getBody() && Function->isImplicitlyInstantiable()) { 7269 bool AlreadyInstantiated = false; 7270 if (FunctionTemplateSpecializationInfo *SpecInfo 7271 = Function->getTemplateSpecializationInfo()) { 7272 if (SpecInfo->getPointOfInstantiation().isInvalid()) 7273 SpecInfo->setPointOfInstantiation(Loc); 7274 else if (SpecInfo->getTemplateSpecializationKind() 7275 == TSK_ImplicitInstantiation) 7276 AlreadyInstantiated = true; 7277 } else if (MemberSpecializationInfo *MSInfo 7278 = Function->getMemberSpecializationInfo()) { 7279 if (MSInfo->getPointOfInstantiation().isInvalid()) 7280 MSInfo->setPointOfInstantiation(Loc); 7281 else if (MSInfo->getTemplateSpecializationKind() 7282 == TSK_ImplicitInstantiation) 7283 AlreadyInstantiated = true; 7284 } 7285 7286 if (!AlreadyInstantiated) { 7287 if (isa<CXXRecordDecl>(Function->getDeclContext()) && 7288 cast<CXXRecordDecl>(Function->getDeclContext())->isLocalClass()) 7289 PendingLocalImplicitInstantiations.push_back(std::make_pair(Function, 7290 Loc)); 7291 else 7292 PendingImplicitInstantiations.push_back(std::make_pair(Function, 7293 Loc)); 7294 } 7295 } 7296 7297 // FIXME: keep track of references to static functions 7298 Function->setUsed(true); 7299 7300 return; 7301 } 7302 7303 if (VarDecl *Var = dyn_cast<VarDecl>(D)) { 7304 // Implicit instantiation of static data members of class templates. 7305 if (Var->isStaticDataMember() && 7306 Var->getInstantiatedFromStaticDataMember()) { 7307 MemberSpecializationInfo *MSInfo = Var->getMemberSpecializationInfo(); 7308 assert(MSInfo && "Missing member specialization information?"); 7309 if (MSInfo->getPointOfInstantiation().isInvalid() && 7310 MSInfo->getTemplateSpecializationKind()== TSK_ImplicitInstantiation) { 7311 MSInfo->setPointOfInstantiation(Loc); 7312 PendingImplicitInstantiations.push_back(std::make_pair(Var, Loc)); 7313 } 7314 } 7315 7316 // FIXME: keep track of references to static data? 7317 7318 D->setUsed(true); 7319 return; 7320 } 7321} 7322 7323/// \brief Emit a diagnostic that describes an effect on the run-time behavior 7324/// of the program being compiled. 7325/// 7326/// This routine emits the given diagnostic when the code currently being 7327/// type-checked is "potentially evaluated", meaning that there is a 7328/// possibility that the code will actually be executable. Code in sizeof() 7329/// expressions, code used only during overload resolution, etc., are not 7330/// potentially evaluated. This routine will suppress such diagnostics or, 7331/// in the absolutely nutty case of potentially potentially evaluated 7332/// expressions (C++ typeid), queue the diagnostic to potentially emit it 7333/// later. 7334/// 7335/// This routine should be used for all diagnostics that describe the run-time 7336/// behavior of a program, such as passing a non-POD value through an ellipsis. 7337/// Failure to do so will likely result in spurious diagnostics or failures 7338/// during overload resolution or within sizeof/alignof/typeof/typeid. 7339bool Sema::DiagRuntimeBehavior(SourceLocation Loc, 7340 const PartialDiagnostic &PD) { 7341 switch (ExprEvalContexts.back().Context ) { 7342 case Unevaluated: 7343 // The argument will never be evaluated, so don't complain. 7344 break; 7345 7346 case PotentiallyEvaluated: 7347 Diag(Loc, PD); 7348 return true; 7349 7350 case PotentiallyPotentiallyEvaluated: 7351 ExprEvalContexts.back().addDiagnostic(Loc, PD); 7352 break; 7353 } 7354 7355 return false; 7356} 7357 7358bool Sema::CheckCallReturnType(QualType ReturnType, SourceLocation Loc, 7359 CallExpr *CE, FunctionDecl *FD) { 7360 if (ReturnType->isVoidType() || !ReturnType->isIncompleteType()) 7361 return false; 7362 7363 PartialDiagnostic Note = 7364 FD ? PDiag(diag::note_function_with_incomplete_return_type_declared_here) 7365 << FD->getDeclName() : PDiag(); 7366 SourceLocation NoteLoc = FD ? FD->getLocation() : SourceLocation(); 7367 7368 if (RequireCompleteType(Loc, ReturnType, 7369 FD ? 7370 PDiag(diag::err_call_function_incomplete_return) 7371 << CE->getSourceRange() << FD->getDeclName() : 7372 PDiag(diag::err_call_incomplete_return) 7373 << CE->getSourceRange(), 7374 std::make_pair(NoteLoc, Note))) 7375 return true; 7376 7377 return false; 7378} 7379 7380// Diagnose the common s/=/==/ typo. Note that adding parentheses 7381// will prevent this condition from triggering, which is what we want. 7382void Sema::DiagnoseAssignmentAsCondition(Expr *E) { 7383 SourceLocation Loc; 7384 7385 unsigned diagnostic = diag::warn_condition_is_assignment; 7386 7387 if (isa<BinaryOperator>(E)) { 7388 BinaryOperator *Op = cast<BinaryOperator>(E); 7389 if (Op->getOpcode() != BinaryOperator::Assign) 7390 return; 7391 7392 // Greylist some idioms by putting them into a warning subcategory. 7393 if (ObjCMessageExpr *ME 7394 = dyn_cast<ObjCMessageExpr>(Op->getRHS()->IgnoreParenCasts())) { 7395 Selector Sel = ME->getSelector(); 7396 7397 // self = [<foo> init...] 7398 if (isSelfExpr(Op->getLHS()) 7399 && Sel.getIdentifierInfoForSlot(0)->getName().startswith("init")) 7400 diagnostic = diag::warn_condition_is_idiomatic_assignment; 7401 7402 // <foo> = [<bar> nextObject] 7403 else if (Sel.isUnarySelector() && 7404 Sel.getIdentifierInfoForSlot(0)->getName() == "nextObject") 7405 diagnostic = diag::warn_condition_is_idiomatic_assignment; 7406 } 7407 7408 Loc = Op->getOperatorLoc(); 7409 } else if (isa<CXXOperatorCallExpr>(E)) { 7410 CXXOperatorCallExpr *Op = cast<CXXOperatorCallExpr>(E); 7411 if (Op->getOperator() != OO_Equal) 7412 return; 7413 7414 Loc = Op->getOperatorLoc(); 7415 } else { 7416 // Not an assignment. 7417 return; 7418 } 7419 7420 SourceLocation Open = E->getSourceRange().getBegin(); 7421 SourceLocation Close = PP.getLocForEndOfToken(E->getSourceRange().getEnd()); 7422 7423 Diag(Loc, diagnostic) 7424 << E->getSourceRange() 7425 << CodeModificationHint::CreateInsertion(Open, "(") 7426 << CodeModificationHint::CreateInsertion(Close, ")"); 7427 Diag(Loc, diag::note_condition_assign_to_comparison) 7428 << CodeModificationHint::CreateReplacement(Loc, "=="); 7429} 7430 7431bool Sema::CheckBooleanCondition(Expr *&E, SourceLocation Loc) { 7432 DiagnoseAssignmentAsCondition(E); 7433 7434 if (!E->isTypeDependent()) { 7435 DefaultFunctionArrayLvalueConversion(E); 7436 7437 QualType T = E->getType(); 7438 7439 if (getLangOptions().CPlusPlus) { 7440 if (CheckCXXBooleanCondition(E)) // C++ 6.4p4 7441 return true; 7442 } else if (!T->isScalarType()) { // C99 6.8.4.1p1 7443 Diag(Loc, diag::err_typecheck_statement_requires_scalar) 7444 << T << E->getSourceRange(); 7445 return true; 7446 } 7447 } 7448 7449 return false; 7450} 7451