SemaExpr.cpp revision a5e76935d79d84e3a00a2fbb47651799f5da7fef
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 "clang/AST/ASTContext.h" 16#include "clang/AST/DeclObjC.h" 17#include "clang/AST/ExprCXX.h" 18#include "clang/AST/ExprObjC.h" 19#include "clang/AST/DeclTemplate.h" 20#include "clang/Lex/Preprocessor.h" 21#include "clang/Lex/LiteralSupport.h" 22#include "clang/Basic/SourceManager.h" 23#include "clang/Basic/TargetInfo.h" 24#include "clang/Parse/DeclSpec.h" 25#include "clang/Parse/Designator.h" 26#include "clang/Parse/Scope.h" 27using namespace clang; 28 29/// \brief Determine whether the use of this declaration is valid, and 30/// emit any corresponding diagnostics. 31/// 32/// This routine diagnoses various problems with referencing 33/// declarations that can occur when using a declaration. For example, 34/// it might warn if a deprecated or unavailable declaration is being 35/// used, or produce an error (and return true) if a C++0x deleted 36/// function is being used. 37/// 38/// \returns true if there was an error (this declaration cannot be 39/// referenced), false otherwise. 40bool Sema::DiagnoseUseOfDecl(NamedDecl *D, SourceLocation Loc) { 41 // See if the decl is deprecated. 42 if (D->getAttr<DeprecatedAttr>()) { 43 // Implementing deprecated stuff requires referencing deprecated 44 // stuff. Don't warn if we are implementing a deprecated 45 // construct. 46 bool isSilenced = false; 47 48 if (NamedDecl *ND = getCurFunctionOrMethodDecl()) { 49 // If this reference happens *in* a deprecated function or method, don't 50 // warn. 51 isSilenced = ND->getAttr<DeprecatedAttr>(); 52 53 // If this is an Objective-C method implementation, check to see if the 54 // method was deprecated on the declaration, not the definition. 55 if (ObjCMethodDecl *MD = dyn_cast<ObjCMethodDecl>(ND)) { 56 // The semantic decl context of a ObjCMethodDecl is the 57 // ObjCImplementationDecl. 58 if (ObjCImplementationDecl *Impl 59 = dyn_cast<ObjCImplementationDecl>(MD->getParent())) { 60 61 MD = Impl->getClassInterface()->getMethod(MD->getSelector(), 62 MD->isInstanceMethod()); 63 isSilenced |= MD && MD->getAttr<DeprecatedAttr>(); 64 } 65 } 66 } 67 68 if (!isSilenced) 69 Diag(Loc, diag::warn_deprecated) << D->getDeclName(); 70 } 71 72 // See if this is a deleted function. 73 if (FunctionDecl *FD = dyn_cast<FunctionDecl>(D)) { 74 if (FD->isDeleted()) { 75 Diag(Loc, diag::err_deleted_function_use); 76 Diag(D->getLocation(), diag::note_unavailable_here) << true; 77 return true; 78 } 79 } 80 81 // See if the decl is unavailable 82 if (D->getAttr<UnavailableAttr>()) { 83 Diag(Loc, diag::warn_unavailable) << D->getDeclName(); 84 Diag(D->getLocation(), diag::note_unavailable_here) << 0; 85 } 86 87 return false; 88} 89 90/// DiagnoseSentinelCalls - This routine checks on method dispatch calls 91/// (and other functions in future), which have been declared with sentinel 92/// attribute. It warns if call does not have the sentinel argument. 93/// 94void Sema::DiagnoseSentinelCalls(NamedDecl *D, SourceLocation Loc, 95 Expr **Args, unsigned NumArgs) 96{ 97 const SentinelAttr *attr = D->getAttr<SentinelAttr>(); 98 if (!attr) 99 return; 100 int sentinelPos = attr->getSentinel(); 101 int nullPos = attr->getNullPos(); 102 103 // FIXME. ObjCMethodDecl and FunctionDecl need be derived from the same common 104 // base class. Then we won't be needing two versions of the same code. 105 unsigned int i = 0; 106 bool warnNotEnoughArgs = false; 107 int isMethod = 0; 108 if (ObjCMethodDecl *MD = dyn_cast<ObjCMethodDecl>(D)) { 109 // skip over named parameters. 110 ObjCMethodDecl::param_iterator P, E = MD->param_end(); 111 for (P = MD->param_begin(); (P != E && i < NumArgs); ++P) { 112 if (nullPos) 113 --nullPos; 114 else 115 ++i; 116 } 117 warnNotEnoughArgs = (P != E || i >= NumArgs); 118 isMethod = 1; 119 } else if (FunctionDecl *FD = dyn_cast<FunctionDecl>(D)) { 120 // skip over named parameters. 121 ObjCMethodDecl::param_iterator P, E = FD->param_end(); 122 for (P = FD->param_begin(); (P != E && i < NumArgs); ++P) { 123 if (nullPos) 124 --nullPos; 125 else 126 ++i; 127 } 128 warnNotEnoughArgs = (P != E || i >= NumArgs); 129 } else if (VarDecl *V = dyn_cast<VarDecl>(D)) { 130 // block or function pointer call. 131 QualType Ty = V->getType(); 132 if (Ty->isBlockPointerType() || Ty->isFunctionPointerType()) { 133 const FunctionType *FT = Ty->isFunctionPointerType() 134 ? Ty->getAs<PointerType>()->getPointeeType()->getAsFunctionType() 135 : Ty->getAs<BlockPointerType>()->getPointeeType()->getAsFunctionType(); 136 if (const FunctionProtoType *Proto = dyn_cast<FunctionProtoType>(FT)) { 137 unsigned NumArgsInProto = Proto->getNumArgs(); 138 unsigned k; 139 for (k = 0; (k != NumArgsInProto && i < NumArgs); k++) { 140 if (nullPos) 141 --nullPos; 142 else 143 ++i; 144 } 145 warnNotEnoughArgs = (k != NumArgsInProto || i >= NumArgs); 146 } 147 if (Ty->isBlockPointerType()) 148 isMethod = 2; 149 } else 150 return; 151 } else 152 return; 153 154 if (warnNotEnoughArgs) { 155 Diag(Loc, diag::warn_not_enough_argument) << D->getDeclName(); 156 Diag(D->getLocation(), diag::note_sentinel_here) << isMethod; 157 return; 158 } 159 int sentinel = i; 160 while (sentinelPos > 0 && i < NumArgs-1) { 161 --sentinelPos; 162 ++i; 163 } 164 if (sentinelPos > 0) { 165 Diag(Loc, diag::warn_not_enough_argument) << D->getDeclName(); 166 Diag(D->getLocation(), diag::note_sentinel_here) << isMethod; 167 return; 168 } 169 while (i < NumArgs-1) { 170 ++i; 171 ++sentinel; 172 } 173 Expr *sentinelExpr = Args[sentinel]; 174 if (sentinelExpr && (!sentinelExpr->getType()->isPointerType() || 175 !sentinelExpr->isNullPointerConstant(Context))) { 176 Diag(Loc, diag::warn_missing_sentinel) << isMethod; 177 Diag(D->getLocation(), diag::note_sentinel_here) << isMethod; 178 } 179 return; 180} 181 182SourceRange Sema::getExprRange(ExprTy *E) const { 183 Expr *Ex = (Expr *)E; 184 return Ex? Ex->getSourceRange() : SourceRange(); 185} 186 187//===----------------------------------------------------------------------===// 188// Standard Promotions and Conversions 189//===----------------------------------------------------------------------===// 190 191/// DefaultFunctionArrayConversion (C99 6.3.2.1p3, C99 6.3.2.1p4). 192void Sema::DefaultFunctionArrayConversion(Expr *&E) { 193 QualType Ty = E->getType(); 194 assert(!Ty.isNull() && "DefaultFunctionArrayConversion - missing type"); 195 196 if (Ty->isFunctionType()) 197 ImpCastExprToType(E, Context.getPointerType(Ty)); 198 else if (Ty->isArrayType()) { 199 // In C90 mode, arrays only promote to pointers if the array expression is 200 // an lvalue. The relevant legalese is C90 6.2.2.1p3: "an lvalue that has 201 // type 'array of type' is converted to an expression that has type 'pointer 202 // to type'...". In C99 this was changed to: C99 6.3.2.1p3: "an expression 203 // that has type 'array of type' ...". The relevant change is "an lvalue" 204 // (C90) to "an expression" (C99). 205 // 206 // C++ 4.2p1: 207 // An lvalue or rvalue of type "array of N T" or "array of unknown bound of 208 // T" can be converted to an rvalue of type "pointer to T". 209 // 210 if (getLangOptions().C99 || getLangOptions().CPlusPlus || 211 E->isLvalue(Context) == Expr::LV_Valid) 212 ImpCastExprToType(E, Context.getArrayDecayedType(Ty), 213 CastExpr::CK_ArrayToPointerDecay); 214 } 215} 216 217/// \brief Whether this is a promotable bitfield reference according 218/// to C99 6.3.1.1p2, bullet 2. 219/// 220/// \returns the type this bit-field will promote to, or NULL if no 221/// promotion occurs. 222static QualType isPromotableBitField(Expr *E, ASTContext &Context) { 223 FieldDecl *Field = E->getBitField(); 224 if (!Field) 225 return QualType(); 226 227 const BuiltinType *BT = Field->getType()->getAsBuiltinType(); 228 if (!BT) 229 return QualType(); 230 231 if (BT->getKind() != BuiltinType::Bool && 232 BT->getKind() != BuiltinType::Int && 233 BT->getKind() != BuiltinType::UInt) 234 return QualType(); 235 236 llvm::APSInt BitWidthAP; 237 if (!Field->getBitWidth()->isIntegerConstantExpr(BitWidthAP, Context)) 238 return QualType(); 239 240 uint64_t BitWidth = BitWidthAP.getZExtValue(); 241 uint64_t IntSize = Context.getTypeSize(Context.IntTy); 242 if (BitWidth < IntSize || 243 (Field->getType()->isSignedIntegerType() && BitWidth == IntSize)) 244 return Context.IntTy; 245 246 if (BitWidth == IntSize && Field->getType()->isUnsignedIntegerType()) 247 return Context.UnsignedIntTy; 248 249 return QualType(); 250} 251 252/// UsualUnaryConversions - Performs various conversions that are common to most 253/// operators (C99 6.3). The conversions of array and function types are 254/// sometimes surpressed. For example, the array->pointer conversion doesn't 255/// apply if the array is an argument to the sizeof or address (&) operators. 256/// In these instances, this routine should *not* be called. 257Expr *Sema::UsualUnaryConversions(Expr *&Expr) { 258 QualType Ty = Expr->getType(); 259 assert(!Ty.isNull() && "UsualUnaryConversions - missing type"); 260 261 // C99 6.3.1.1p2: 262 // 263 // The following may be used in an expression wherever an int or 264 // unsigned int may be used: 265 // - an object or expression with an integer type whose integer 266 // conversion rank is less than or equal to the rank of int 267 // and unsigned int. 268 // - A bit-field of type _Bool, int, signed int, or unsigned int. 269 // 270 // If an int can represent all values of the original type, the 271 // value is converted to an int; otherwise, it is converted to an 272 // unsigned int. These are called the integer promotions. All 273 // other types are unchanged by the integer promotions. 274 if (Ty->isPromotableIntegerType()) { 275 ImpCastExprToType(Expr, Context.IntTy); 276 return Expr; 277 } else { 278 QualType T = isPromotableBitField(Expr, Context); 279 if (!T.isNull()) { 280 ImpCastExprToType(Expr, T); 281 return Expr; 282 } 283 } 284 285 DefaultFunctionArrayConversion(Expr); 286 return Expr; 287} 288 289/// DefaultArgumentPromotion (C99 6.5.2.2p6). Used for function calls that 290/// do not have a prototype. Arguments that have type float are promoted to 291/// double. All other argument types are converted by UsualUnaryConversions(). 292void Sema::DefaultArgumentPromotion(Expr *&Expr) { 293 QualType Ty = Expr->getType(); 294 assert(!Ty.isNull() && "DefaultArgumentPromotion - missing type"); 295 296 // If this is a 'float' (CVR qualified or typedef) promote to double. 297 if (const BuiltinType *BT = Ty->getAsBuiltinType()) 298 if (BT->getKind() == BuiltinType::Float) 299 return ImpCastExprToType(Expr, Context.DoubleTy); 300 301 UsualUnaryConversions(Expr); 302} 303 304/// DefaultVariadicArgumentPromotion - Like DefaultArgumentPromotion, but 305/// will warn if the resulting type is not a POD type, and rejects ObjC 306/// interfaces passed by value. This returns true if the argument type is 307/// completely illegal. 308bool Sema::DefaultVariadicArgumentPromotion(Expr *&Expr, VariadicCallType CT) { 309 DefaultArgumentPromotion(Expr); 310 311 if (Expr->getType()->isObjCInterfaceType()) { 312 Diag(Expr->getLocStart(), 313 diag::err_cannot_pass_objc_interface_to_vararg) 314 << Expr->getType() << CT; 315 return true; 316 } 317 318 if (!Expr->getType()->isPODType()) 319 Diag(Expr->getLocStart(), diag::warn_cannot_pass_non_pod_arg_to_vararg) 320 << Expr->getType() << CT; 321 322 return false; 323} 324 325 326/// UsualArithmeticConversions - Performs various conversions that are common to 327/// binary operators (C99 6.3.1.8). If both operands aren't arithmetic, this 328/// routine returns the first non-arithmetic type found. The client is 329/// responsible for emitting appropriate error diagnostics. 330/// FIXME: verify the conversion rules for "complex int" are consistent with 331/// GCC. 332QualType Sema::UsualArithmeticConversions(Expr *&lhsExpr, Expr *&rhsExpr, 333 bool isCompAssign) { 334 if (!isCompAssign) 335 UsualUnaryConversions(lhsExpr); 336 337 UsualUnaryConversions(rhsExpr); 338 339 // For conversion purposes, we ignore any qualifiers. 340 // For example, "const float" and "float" are equivalent. 341 QualType lhs = 342 Context.getCanonicalType(lhsExpr->getType()).getUnqualifiedType(); 343 QualType rhs = 344 Context.getCanonicalType(rhsExpr->getType()).getUnqualifiedType(); 345 346 // If both types are identical, no conversion is needed. 347 if (lhs == rhs) 348 return lhs; 349 350 // If either side is a non-arithmetic type (e.g. a pointer), we are done. 351 // The caller can deal with this (e.g. pointer + int). 352 if (!lhs->isArithmeticType() || !rhs->isArithmeticType()) 353 return lhs; 354 355 // Perform bitfield promotions. 356 QualType LHSBitfieldPromoteTy = isPromotableBitField(lhsExpr, Context); 357 if (!LHSBitfieldPromoteTy.isNull()) 358 lhs = LHSBitfieldPromoteTy; 359 QualType RHSBitfieldPromoteTy = isPromotableBitField(rhsExpr, Context); 360 if (!RHSBitfieldPromoteTy.isNull()) 361 rhs = RHSBitfieldPromoteTy; 362 363 QualType destType = UsualArithmeticConversionsType(lhs, rhs); 364 if (!isCompAssign) 365 ImpCastExprToType(lhsExpr, destType); 366 ImpCastExprToType(rhsExpr, destType); 367 return destType; 368} 369 370QualType Sema::UsualArithmeticConversionsType(QualType lhs, QualType rhs) { 371 // Perform the usual unary conversions. We do this early so that 372 // integral promotions to "int" can allow us to exit early, in the 373 // lhs == rhs check. Also, for conversion purposes, we ignore any 374 // qualifiers. For example, "const float" and "float" are 375 // equivalent. 376 if (lhs->isPromotableIntegerType()) 377 lhs = Context.IntTy; 378 else 379 lhs = lhs.getUnqualifiedType(); 380 if (rhs->isPromotableIntegerType()) 381 rhs = Context.IntTy; 382 else 383 rhs = rhs.getUnqualifiedType(); 384 385 // If both types are identical, no conversion is needed. 386 if (lhs == rhs) 387 return lhs; 388 389 // If either side is a non-arithmetic type (e.g. a pointer), we are done. 390 // The caller can deal with this (e.g. pointer + int). 391 if (!lhs->isArithmeticType() || !rhs->isArithmeticType()) 392 return lhs; 393 394 // At this point, we have two different arithmetic types. 395 396 // Handle complex types first (C99 6.3.1.8p1). 397 if (lhs->isComplexType() || rhs->isComplexType()) { 398 // if we have an integer operand, the result is the complex type. 399 if (rhs->isIntegerType() || rhs->isComplexIntegerType()) { 400 // convert the rhs to the lhs complex type. 401 return lhs; 402 } 403 if (lhs->isIntegerType() || lhs->isComplexIntegerType()) { 404 // convert the lhs to the rhs complex type. 405 return rhs; 406 } 407 // This handles complex/complex, complex/float, or float/complex. 408 // When both operands are complex, the shorter operand is converted to the 409 // type of the longer, and that is the type of the result. This corresponds 410 // to what is done when combining two real floating-point operands. 411 // The fun begins when size promotion occur across type domains. 412 // From H&S 6.3.4: When one operand is complex and the other is a real 413 // floating-point type, the less precise type is converted, within it's 414 // real or complex domain, to the precision of the other type. For example, 415 // when combining a "long double" with a "double _Complex", the 416 // "double _Complex" is promoted to "long double _Complex". 417 int result = Context.getFloatingTypeOrder(lhs, rhs); 418 419 if (result > 0) { // The left side is bigger, convert rhs. 420 rhs = Context.getFloatingTypeOfSizeWithinDomain(lhs, rhs); 421 } else if (result < 0) { // The right side is bigger, convert lhs. 422 lhs = Context.getFloatingTypeOfSizeWithinDomain(rhs, lhs); 423 } 424 // At this point, lhs and rhs have the same rank/size. Now, make sure the 425 // domains match. This is a requirement for our implementation, C99 426 // does not require this promotion. 427 if (lhs != rhs) { // Domains don't match, we have complex/float mix. 428 if (lhs->isRealFloatingType()) { // handle "double, _Complex double". 429 return rhs; 430 } else { // handle "_Complex double, double". 431 return lhs; 432 } 433 } 434 return lhs; // The domain/size match exactly. 435 } 436 // Now handle "real" floating types (i.e. float, double, long double). 437 if (lhs->isRealFloatingType() || rhs->isRealFloatingType()) { 438 // if we have an integer operand, the result is the real floating type. 439 if (rhs->isIntegerType()) { 440 // convert rhs to the lhs floating point type. 441 return lhs; 442 } 443 if (rhs->isComplexIntegerType()) { 444 // convert rhs to the complex floating point type. 445 return Context.getComplexType(lhs); 446 } 447 if (lhs->isIntegerType()) { 448 // convert lhs to the rhs floating point type. 449 return rhs; 450 } 451 if (lhs->isComplexIntegerType()) { 452 // convert lhs to the complex floating point type. 453 return Context.getComplexType(rhs); 454 } 455 // We have two real floating types, float/complex combos were handled above. 456 // Convert the smaller operand to the bigger result. 457 int result = Context.getFloatingTypeOrder(lhs, rhs); 458 if (result > 0) // convert the rhs 459 return lhs; 460 assert(result < 0 && "illegal float comparison"); 461 return rhs; // convert the lhs 462 } 463 if (lhs->isComplexIntegerType() || rhs->isComplexIntegerType()) { 464 // Handle GCC complex int extension. 465 const ComplexType *lhsComplexInt = lhs->getAsComplexIntegerType(); 466 const ComplexType *rhsComplexInt = rhs->getAsComplexIntegerType(); 467 468 if (lhsComplexInt && rhsComplexInt) { 469 if (Context.getIntegerTypeOrder(lhsComplexInt->getElementType(), 470 rhsComplexInt->getElementType()) >= 0) 471 return lhs; // convert the rhs 472 return rhs; 473 } else if (lhsComplexInt && rhs->isIntegerType()) { 474 // convert the rhs to the lhs complex type. 475 return lhs; 476 } else if (rhsComplexInt && lhs->isIntegerType()) { 477 // convert the lhs to the rhs complex type. 478 return rhs; 479 } 480 } 481 // Finally, we have two differing integer types. 482 // The rules for this case are in C99 6.3.1.8 483 int compare = Context.getIntegerTypeOrder(lhs, rhs); 484 bool lhsSigned = lhs->isSignedIntegerType(), 485 rhsSigned = rhs->isSignedIntegerType(); 486 QualType destType; 487 if (lhsSigned == rhsSigned) { 488 // Same signedness; use the higher-ranked type 489 destType = compare >= 0 ? lhs : rhs; 490 } else if (compare != (lhsSigned ? 1 : -1)) { 491 // The unsigned type has greater than or equal rank to the 492 // signed type, so use the unsigned type 493 destType = lhsSigned ? rhs : lhs; 494 } else if (Context.getIntWidth(lhs) != Context.getIntWidth(rhs)) { 495 // The two types are different widths; if we are here, that 496 // means the signed type is larger than the unsigned type, so 497 // use the signed type. 498 destType = lhsSigned ? lhs : rhs; 499 } else { 500 // The signed type is higher-ranked than the unsigned type, 501 // but isn't actually any bigger (like unsigned int and long 502 // on most 32-bit systems). Use the unsigned type corresponding 503 // to the signed type. 504 destType = Context.getCorrespondingUnsignedType(lhsSigned ? lhs : rhs); 505 } 506 return destType; 507} 508 509//===----------------------------------------------------------------------===// 510// Semantic Analysis for various Expression Types 511//===----------------------------------------------------------------------===// 512 513 514/// ActOnStringLiteral - The specified tokens were lexed as pasted string 515/// fragments (e.g. "foo" "bar" L"baz"). The result string has to handle string 516/// concatenation ([C99 5.1.1.2, translation phase #6]), so it may come from 517/// multiple tokens. However, the common case is that StringToks points to one 518/// string. 519/// 520Action::OwningExprResult 521Sema::ActOnStringLiteral(const Token *StringToks, unsigned NumStringToks) { 522 assert(NumStringToks && "Must have at least one string!"); 523 524 StringLiteralParser Literal(StringToks, NumStringToks, PP); 525 if (Literal.hadError) 526 return ExprError(); 527 528 llvm::SmallVector<SourceLocation, 4> StringTokLocs; 529 for (unsigned i = 0; i != NumStringToks; ++i) 530 StringTokLocs.push_back(StringToks[i].getLocation()); 531 532 QualType StrTy = Context.CharTy; 533 if (Literal.AnyWide) StrTy = Context.getWCharType(); 534 if (Literal.Pascal) StrTy = Context.UnsignedCharTy; 535 536 // A C++ string literal has a const-qualified element type (C++ 2.13.4p1). 537 if (getLangOptions().CPlusPlus) 538 StrTy.addConst(); 539 540 // Get an array type for the string, according to C99 6.4.5. This includes 541 // the nul terminator character as well as the string length for pascal 542 // strings. 543 StrTy = Context.getConstantArrayType(StrTy, 544 llvm::APInt(32, Literal.GetNumStringChars()+1), 545 ArrayType::Normal, 0); 546 547 // Pass &StringTokLocs[0], StringTokLocs.size() to factory! 548 return Owned(StringLiteral::Create(Context, Literal.GetString(), 549 Literal.GetStringLength(), 550 Literal.AnyWide, StrTy, 551 &StringTokLocs[0], 552 StringTokLocs.size())); 553} 554 555/// ShouldSnapshotBlockValueReference - Return true if a reference inside of 556/// CurBlock to VD should cause it to be snapshotted (as we do for auto 557/// variables defined outside the block) or false if this is not needed (e.g. 558/// for values inside the block or for globals). 559/// 560/// This also keeps the 'hasBlockDeclRefExprs' in the BlockSemaInfo records 561/// up-to-date. 562/// 563static bool ShouldSnapshotBlockValueReference(BlockSemaInfo *CurBlock, 564 ValueDecl *VD) { 565 // If the value is defined inside the block, we couldn't snapshot it even if 566 // we wanted to. 567 if (CurBlock->TheDecl == VD->getDeclContext()) 568 return false; 569 570 // If this is an enum constant or function, it is constant, don't snapshot. 571 if (isa<EnumConstantDecl>(VD) || isa<FunctionDecl>(VD)) 572 return false; 573 574 // If this is a reference to an extern, static, or global variable, no need to 575 // snapshot it. 576 // FIXME: What about 'const' variables in C++? 577 if (const VarDecl *Var = dyn_cast<VarDecl>(VD)) 578 if (!Var->hasLocalStorage()) 579 return false; 580 581 // Blocks that have these can't be constant. 582 CurBlock->hasBlockDeclRefExprs = true; 583 584 // If we have nested blocks, the decl may be declared in an outer block (in 585 // which case that outer block doesn't get "hasBlockDeclRefExprs") or it may 586 // be defined outside all of the current blocks (in which case the blocks do 587 // all get the bit). Walk the nesting chain. 588 for (BlockSemaInfo *NextBlock = CurBlock->PrevBlockInfo; NextBlock; 589 NextBlock = NextBlock->PrevBlockInfo) { 590 // If we found the defining block for the variable, don't mark the block as 591 // having a reference outside it. 592 if (NextBlock->TheDecl == VD->getDeclContext()) 593 break; 594 595 // Otherwise, the DeclRef from the inner block causes the outer one to need 596 // a snapshot as well. 597 NextBlock->hasBlockDeclRefExprs = true; 598 } 599 600 return true; 601} 602 603 604 605/// ActOnIdentifierExpr - The parser read an identifier in expression context, 606/// validate it per-C99 6.5.1. HasTrailingLParen indicates whether this 607/// identifier is used in a function call context. 608/// SS is only used for a C++ qualified-id (foo::bar) to indicate the 609/// class or namespace that the identifier must be a member of. 610Sema::OwningExprResult Sema::ActOnIdentifierExpr(Scope *S, SourceLocation Loc, 611 IdentifierInfo &II, 612 bool HasTrailingLParen, 613 const CXXScopeSpec *SS, 614 bool isAddressOfOperand) { 615 return ActOnDeclarationNameExpr(S, Loc, &II, HasTrailingLParen, SS, 616 isAddressOfOperand); 617} 618 619/// BuildDeclRefExpr - Build either a DeclRefExpr or a 620/// QualifiedDeclRefExpr based on whether or not SS is a 621/// nested-name-specifier. 622Sema::OwningExprResult 623Sema::BuildDeclRefExpr(NamedDecl *D, QualType Ty, SourceLocation Loc, 624 bool TypeDependent, bool ValueDependent, 625 const CXXScopeSpec *SS) { 626 if (Context.getCanonicalType(Ty) == Context.UndeducedAutoTy) { 627 Diag(Loc, 628 diag::err_auto_variable_cannot_appear_in_own_initializer) 629 << D->getDeclName(); 630 return ExprError(); 631 } 632 633 if (const VarDecl *VD = dyn_cast<VarDecl>(D)) { 634 if (const CXXMethodDecl *MD = dyn_cast<CXXMethodDecl>(CurContext)) { 635 if (const FunctionDecl *FD = MD->getParent()->isLocalClass()) { 636 if (VD->hasLocalStorage() && VD->getDeclContext() != CurContext) { 637 Diag(Loc, diag::err_reference_to_local_var_in_enclosing_function) 638 << D->getIdentifier() << FD->getDeclName(); 639 Diag(D->getLocation(), diag::note_local_variable_declared_here) 640 << D->getIdentifier(); 641 return ExprError(); 642 } 643 } 644 } 645 } 646 647 MarkDeclarationReferenced(Loc, D); 648 649 Expr *E; 650 if (SS && !SS->isEmpty()) { 651 E = new (Context) QualifiedDeclRefExpr(D, Ty, Loc, TypeDependent, 652 ValueDependent, SS->getRange(), 653 static_cast<NestedNameSpecifier *>(SS->getScopeRep())); 654 } else 655 E = new (Context) DeclRefExpr(D, Ty, Loc, TypeDependent, ValueDependent); 656 657 return Owned(E); 658} 659 660/// getObjectForAnonymousRecordDecl - Retrieve the (unnamed) field or 661/// variable corresponding to the anonymous union or struct whose type 662/// is Record. 663static Decl *getObjectForAnonymousRecordDecl(ASTContext &Context, 664 RecordDecl *Record) { 665 assert(Record->isAnonymousStructOrUnion() && 666 "Record must be an anonymous struct or union!"); 667 668 // FIXME: Once Decls are directly linked together, this will be an O(1) 669 // operation rather than a slow walk through DeclContext's vector (which 670 // itself will be eliminated). DeclGroups might make this even better. 671 DeclContext *Ctx = Record->getDeclContext(); 672 for (DeclContext::decl_iterator D = Ctx->decls_begin(), 673 DEnd = Ctx->decls_end(); 674 D != DEnd; ++D) { 675 if (*D == Record) { 676 // The object for the anonymous struct/union directly 677 // follows its type in the list of declarations. 678 ++D; 679 assert(D != DEnd && "Missing object for anonymous record"); 680 assert(!cast<NamedDecl>(*D)->getDeclName() && "Decl should be unnamed"); 681 return *D; 682 } 683 } 684 685 assert(false && "Missing object for anonymous record"); 686 return 0; 687} 688 689/// \brief Given a field that represents a member of an anonymous 690/// struct/union, build the path from that field's context to the 691/// actual member. 692/// 693/// Construct the sequence of field member references we'll have to 694/// perform to get to the field in the anonymous union/struct. The 695/// list of members is built from the field outward, so traverse it 696/// backwards to go from an object in the current context to the field 697/// we found. 698/// 699/// \returns The variable from which the field access should begin, 700/// for an anonymous struct/union that is not a member of another 701/// class. Otherwise, returns NULL. 702VarDecl *Sema::BuildAnonymousStructUnionMemberPath(FieldDecl *Field, 703 llvm::SmallVectorImpl<FieldDecl *> &Path) { 704 assert(Field->getDeclContext()->isRecord() && 705 cast<RecordDecl>(Field->getDeclContext())->isAnonymousStructOrUnion() 706 && "Field must be stored inside an anonymous struct or union"); 707 708 Path.push_back(Field); 709 VarDecl *BaseObject = 0; 710 DeclContext *Ctx = Field->getDeclContext(); 711 do { 712 RecordDecl *Record = cast<RecordDecl>(Ctx); 713 Decl *AnonObject = getObjectForAnonymousRecordDecl(Context, Record); 714 if (FieldDecl *AnonField = dyn_cast<FieldDecl>(AnonObject)) 715 Path.push_back(AnonField); 716 else { 717 BaseObject = cast<VarDecl>(AnonObject); 718 break; 719 } 720 Ctx = Ctx->getParent(); 721 } while (Ctx->isRecord() && 722 cast<RecordDecl>(Ctx)->isAnonymousStructOrUnion()); 723 724 return BaseObject; 725} 726 727Sema::OwningExprResult 728Sema::BuildAnonymousStructUnionMemberReference(SourceLocation Loc, 729 FieldDecl *Field, 730 Expr *BaseObjectExpr, 731 SourceLocation OpLoc) { 732 llvm::SmallVector<FieldDecl *, 4> AnonFields; 733 VarDecl *BaseObject = BuildAnonymousStructUnionMemberPath(Field, 734 AnonFields); 735 736 // Build the expression that refers to the base object, from 737 // which we will build a sequence of member references to each 738 // of the anonymous union objects and, eventually, the field we 739 // found via name lookup. 740 bool BaseObjectIsPointer = false; 741 unsigned ExtraQuals = 0; 742 if (BaseObject) { 743 // BaseObject is an anonymous struct/union variable (and is, 744 // therefore, not part of another non-anonymous record). 745 if (BaseObjectExpr) BaseObjectExpr->Destroy(Context); 746 MarkDeclarationReferenced(Loc, BaseObject); 747 BaseObjectExpr = new (Context) DeclRefExpr(BaseObject,BaseObject->getType(), 748 SourceLocation()); 749 ExtraQuals 750 = Context.getCanonicalType(BaseObject->getType()).getCVRQualifiers(); 751 } else if (BaseObjectExpr) { 752 // The caller provided the base object expression. Determine 753 // whether its a pointer and whether it adds any qualifiers to the 754 // anonymous struct/union fields we're looking into. 755 QualType ObjectType = BaseObjectExpr->getType(); 756 if (const PointerType *ObjectPtr = ObjectType->getAs<PointerType>()) { 757 BaseObjectIsPointer = true; 758 ObjectType = ObjectPtr->getPointeeType(); 759 } 760 ExtraQuals = Context.getCanonicalType(ObjectType).getCVRQualifiers(); 761 } else { 762 // We've found a member of an anonymous struct/union that is 763 // inside a non-anonymous struct/union, so in a well-formed 764 // program our base object expression is "this". 765 if (CXXMethodDecl *MD = dyn_cast<CXXMethodDecl>(CurContext)) { 766 if (!MD->isStatic()) { 767 QualType AnonFieldType 768 = Context.getTagDeclType( 769 cast<RecordDecl>(AnonFields.back()->getDeclContext())); 770 QualType ThisType = Context.getTagDeclType(MD->getParent()); 771 if ((Context.getCanonicalType(AnonFieldType) 772 == Context.getCanonicalType(ThisType)) || 773 IsDerivedFrom(ThisType, AnonFieldType)) { 774 // Our base object expression is "this". 775 BaseObjectExpr = new (Context) CXXThisExpr(SourceLocation(), 776 MD->getThisType(Context)); 777 BaseObjectIsPointer = true; 778 } 779 } else { 780 return ExprError(Diag(Loc,diag::err_invalid_member_use_in_static_method) 781 << Field->getDeclName()); 782 } 783 ExtraQuals = MD->getTypeQualifiers(); 784 } 785 786 if (!BaseObjectExpr) 787 return ExprError(Diag(Loc, diag::err_invalid_non_static_member_use) 788 << Field->getDeclName()); 789 } 790 791 // Build the implicit member references to the field of the 792 // anonymous struct/union. 793 Expr *Result = BaseObjectExpr; 794 unsigned BaseAddrSpace = BaseObjectExpr->getType().getAddressSpace(); 795 for (llvm::SmallVector<FieldDecl *, 4>::reverse_iterator 796 FI = AnonFields.rbegin(), FIEnd = AnonFields.rend(); 797 FI != FIEnd; ++FI) { 798 QualType MemberType = (*FI)->getType(); 799 if (!(*FI)->isMutable()) { 800 unsigned combinedQualifiers 801 = MemberType.getCVRQualifiers() | ExtraQuals; 802 MemberType = MemberType.getQualifiedType(combinedQualifiers); 803 } 804 if (BaseAddrSpace != MemberType.getAddressSpace()) 805 MemberType = Context.getAddrSpaceQualType(MemberType, BaseAddrSpace); 806 MarkDeclarationReferenced(Loc, *FI); 807 Result = new (Context) MemberExpr(Result, BaseObjectIsPointer, *FI, 808 OpLoc, MemberType); 809 BaseObjectIsPointer = false; 810 ExtraQuals = Context.getCanonicalType(MemberType).getCVRQualifiers(); 811 } 812 813 return Owned(Result); 814} 815 816/// ActOnDeclarationNameExpr - The parser has read some kind of name 817/// (e.g., a C++ id-expression (C++ [expr.prim]p1)). This routine 818/// performs lookup on that name and returns an expression that refers 819/// to that name. This routine isn't directly called from the parser, 820/// because the parser doesn't know about DeclarationName. Rather, 821/// this routine is called by ActOnIdentifierExpr, 822/// ActOnOperatorFunctionIdExpr, and ActOnConversionFunctionExpr, 823/// which form the DeclarationName from the corresponding syntactic 824/// forms. 825/// 826/// HasTrailingLParen indicates whether this identifier is used in a 827/// function call context. LookupCtx is only used for a C++ 828/// qualified-id (foo::bar) to indicate the class or namespace that 829/// the identifier must be a member of. 830/// 831/// isAddressOfOperand means that this expression is the direct operand 832/// of an address-of operator. This matters because this is the only 833/// situation where a qualified name referencing a non-static member may 834/// appear outside a member function of this class. 835Sema::OwningExprResult 836Sema::ActOnDeclarationNameExpr(Scope *S, SourceLocation Loc, 837 DeclarationName Name, bool HasTrailingLParen, 838 const CXXScopeSpec *SS, 839 bool isAddressOfOperand) { 840 // Could be enum-constant, value decl, instance variable, etc. 841 if (SS && SS->isInvalid()) 842 return ExprError(); 843 844 // C++ [temp.dep.expr]p3: 845 // An id-expression is type-dependent if it contains: 846 // -- a nested-name-specifier that contains a class-name that 847 // names a dependent type. 848 // FIXME: Member of the current instantiation. 849 if (SS && isDependentScopeSpecifier(*SS)) { 850 return Owned(new (Context) UnresolvedDeclRefExpr(Name, Context.DependentTy, 851 Loc, SS->getRange(), 852 static_cast<NestedNameSpecifier *>(SS->getScopeRep()), 853 isAddressOfOperand)); 854 } 855 856 LookupResult Lookup = LookupParsedName(S, SS, Name, LookupOrdinaryName, 857 false, true, Loc); 858 859 if (Lookup.isAmbiguous()) { 860 DiagnoseAmbiguousLookup(Lookup, Name, Loc, 861 SS && SS->isSet() ? SS->getRange() 862 : SourceRange()); 863 return ExprError(); 864 } 865 866 NamedDecl *D = Lookup.getAsDecl(); 867 868 // If this reference is in an Objective-C method, then ivar lookup happens as 869 // well. 870 IdentifierInfo *II = Name.getAsIdentifierInfo(); 871 if (II && getCurMethodDecl()) { 872 // There are two cases to handle here. 1) scoped lookup could have failed, 873 // in which case we should look for an ivar. 2) scoped lookup could have 874 // found a decl, but that decl is outside the current instance method (i.e. 875 // a global variable). In these two cases, we do a lookup for an ivar with 876 // this name, if the lookup sucedes, we replace it our current decl. 877 if (D == 0 || D->isDefinedOutsideFunctionOrMethod()) { 878 ObjCInterfaceDecl *IFace = getCurMethodDecl()->getClassInterface(); 879 ObjCInterfaceDecl *ClassDeclared; 880 if (ObjCIvarDecl *IV = IFace->lookupInstanceVariable(II, ClassDeclared)) { 881 // Check if referencing a field with __attribute__((deprecated)). 882 if (DiagnoseUseOfDecl(IV, Loc)) 883 return ExprError(); 884 885 // If we're referencing an invalid decl, just return this as a silent 886 // error node. The error diagnostic was already emitted on the decl. 887 if (IV->isInvalidDecl()) 888 return ExprError(); 889 890 bool IsClsMethod = getCurMethodDecl()->isClassMethod(); 891 // If a class method attemps to use a free standing ivar, this is 892 // an error. 893 if (IsClsMethod && D && !D->isDefinedOutsideFunctionOrMethod()) 894 return ExprError(Diag(Loc, diag::error_ivar_use_in_class_method) 895 << IV->getDeclName()); 896 // If a class method uses a global variable, even if an ivar with 897 // same name exists, use the global. 898 if (!IsClsMethod) { 899 if (IV->getAccessControl() == ObjCIvarDecl::Private && 900 ClassDeclared != IFace) 901 Diag(Loc, diag::error_private_ivar_access) << IV->getDeclName(); 902 // FIXME: This should use a new expr for a direct reference, don't 903 // turn this into Self->ivar, just return a BareIVarExpr or something. 904 IdentifierInfo &II = Context.Idents.get("self"); 905 OwningExprResult SelfExpr = ActOnIdentifierExpr(S, SourceLocation(), 906 II, false); 907 MarkDeclarationReferenced(Loc, IV); 908 return Owned(new (Context) 909 ObjCIvarRefExpr(IV, IV->getType(), Loc, 910 SelfExpr.takeAs<Expr>(), true, true)); 911 } 912 } 913 } else if (getCurMethodDecl()->isInstanceMethod()) { 914 // We should warn if a local variable hides an ivar. 915 ObjCInterfaceDecl *IFace = getCurMethodDecl()->getClassInterface(); 916 ObjCInterfaceDecl *ClassDeclared; 917 if (ObjCIvarDecl *IV = IFace->lookupInstanceVariable(II, ClassDeclared)) { 918 if (IV->getAccessControl() != ObjCIvarDecl::Private || 919 IFace == ClassDeclared) 920 Diag(Loc, diag::warn_ivar_use_hidden) << IV->getDeclName(); 921 } 922 } 923 // Needed to implement property "super.method" notation. 924 if (D == 0 && II->isStr("super")) { 925 QualType T; 926 927 if (getCurMethodDecl()->isInstanceMethod()) 928 T = Context.getObjCObjectPointerType(Context.getObjCInterfaceType( 929 getCurMethodDecl()->getClassInterface())); 930 else 931 T = Context.getObjCClassType(); 932 return Owned(new (Context) ObjCSuperExpr(Loc, T)); 933 } 934 } 935 936 // Determine whether this name might be a candidate for 937 // argument-dependent lookup. 938 bool ADL = getLangOptions().CPlusPlus && (!SS || !SS->isSet()) && 939 HasTrailingLParen; 940 941 if (ADL && D == 0) { 942 // We've seen something of the form 943 // 944 // identifier( 945 // 946 // and we did not find any entity by the name 947 // "identifier". However, this identifier is still subject to 948 // argument-dependent lookup, so keep track of the name. 949 return Owned(new (Context) UnresolvedFunctionNameExpr(Name, 950 Context.OverloadTy, 951 Loc)); 952 } 953 954 if (D == 0) { 955 // Otherwise, this could be an implicitly declared function reference (legal 956 // in C90, extension in C99). 957 if (HasTrailingLParen && II && 958 !getLangOptions().CPlusPlus) // Not in C++. 959 D = ImplicitlyDefineFunction(Loc, *II, S); 960 else { 961 // If this name wasn't predeclared and if this is not a function call, 962 // diagnose the problem. 963 if (SS && !SS->isEmpty()) 964 return ExprError(Diag(Loc, diag::err_typecheck_no_member) 965 << Name << SS->getRange()); 966 else if (Name.getNameKind() == DeclarationName::CXXOperatorName || 967 Name.getNameKind() == DeclarationName::CXXConversionFunctionName) 968 return ExprError(Diag(Loc, diag::err_undeclared_use) 969 << Name.getAsString()); 970 else 971 return ExprError(Diag(Loc, diag::err_undeclared_var_use) << Name); 972 } 973 } 974 975 if (VarDecl *Var = dyn_cast<VarDecl>(D)) { 976 // Warn about constructs like: 977 // if (void *X = foo()) { ... } else { X }. 978 // In the else block, the pointer is always false. 979 980 // FIXME: In a template instantiation, we don't have scope 981 // information to check this property. 982 if (Var->isDeclaredInCondition() && Var->getType()->isScalarType()) { 983 Scope *CheckS = S; 984 while (CheckS) { 985 if (CheckS->isWithinElse() && 986 CheckS->getControlParent()->isDeclScope(DeclPtrTy::make(Var))) { 987 if (Var->getType()->isBooleanType()) 988 ExprError(Diag(Loc, diag::warn_value_always_false) 989 << Var->getDeclName()); 990 else 991 ExprError(Diag(Loc, diag::warn_value_always_zero) 992 << Var->getDeclName()); 993 break; 994 } 995 996 // Move up one more control parent to check again. 997 CheckS = CheckS->getControlParent(); 998 if (CheckS) 999 CheckS = CheckS->getParent(); 1000 } 1001 } 1002 } else if (FunctionDecl *Func = dyn_cast<FunctionDecl>(D)) { 1003 if (!getLangOptions().CPlusPlus && !Func->hasPrototype()) { 1004 // C99 DR 316 says that, if a function type comes from a 1005 // function definition (without a prototype), that type is only 1006 // used for checking compatibility. Therefore, when referencing 1007 // the function, we pretend that we don't have the full function 1008 // type. 1009 if (DiagnoseUseOfDecl(Func, Loc)) 1010 return ExprError(); 1011 1012 QualType T = Func->getType(); 1013 QualType NoProtoType = T; 1014 if (const FunctionProtoType *Proto = T->getAsFunctionProtoType()) 1015 NoProtoType = Context.getFunctionNoProtoType(Proto->getResultType()); 1016 return BuildDeclRefExpr(Func, NoProtoType, Loc, false, false, SS); 1017 } 1018 } 1019 1020 return BuildDeclarationNameExpr(Loc, D, HasTrailingLParen, SS, isAddressOfOperand); 1021} 1022/// \brief Cast member's object to its own class if necessary. 1023bool 1024Sema::PerformObjectMemberConversion(Expr *&From, NamedDecl *Member) { 1025 if (FieldDecl *FD = dyn_cast<FieldDecl>(Member)) 1026 if (CXXRecordDecl *RD = 1027 dyn_cast<CXXRecordDecl>(FD->getDeclContext())) { 1028 QualType DestType = 1029 Context.getCanonicalType(Context.getTypeDeclType(RD)); 1030 if (DestType->isDependentType() || From->getType()->isDependentType()) 1031 return false; 1032 QualType FromRecordType = From->getType(); 1033 QualType DestRecordType = DestType; 1034 if (FromRecordType->getAs<PointerType>()) { 1035 DestType = Context.getPointerType(DestType); 1036 FromRecordType = FromRecordType->getPointeeType(); 1037 } 1038 if (!Context.hasSameUnqualifiedType(FromRecordType, DestRecordType) && 1039 CheckDerivedToBaseConversion(FromRecordType, 1040 DestRecordType, 1041 From->getSourceRange().getBegin(), 1042 From->getSourceRange())) 1043 return true; 1044 ImpCastExprToType(From, DestType, CastExpr::CK_DerivedToBase, 1045 /*isLvalue=*/true); 1046 } 1047 return false; 1048} 1049 1050/// \brief Complete semantic analysis for a reference to the given declaration. 1051Sema::OwningExprResult 1052Sema::BuildDeclarationNameExpr(SourceLocation Loc, NamedDecl *D, 1053 bool HasTrailingLParen, 1054 const CXXScopeSpec *SS, 1055 bool isAddressOfOperand) { 1056 assert(D && "Cannot refer to a NULL declaration"); 1057 DeclarationName Name = D->getDeclName(); 1058 1059 // If this is an expression of the form &Class::member, don't build an 1060 // implicit member ref, because we want a pointer to the member in general, 1061 // not any specific instance's member. 1062 if (isAddressOfOperand && SS && !SS->isEmpty() && !HasTrailingLParen) { 1063 DeclContext *DC = computeDeclContext(*SS); 1064 if (D && isa<CXXRecordDecl>(DC)) { 1065 QualType DType; 1066 if (FieldDecl *FD = dyn_cast<FieldDecl>(D)) { 1067 DType = FD->getType().getNonReferenceType(); 1068 } else if (CXXMethodDecl *Method = dyn_cast<CXXMethodDecl>(D)) { 1069 DType = Method->getType(); 1070 } else if (isa<OverloadedFunctionDecl>(D)) { 1071 DType = Context.OverloadTy; 1072 } 1073 // Could be an inner type. That's diagnosed below, so ignore it here. 1074 if (!DType.isNull()) { 1075 // The pointer is type- and value-dependent if it points into something 1076 // dependent. 1077 bool Dependent = DC->isDependentContext(); 1078 return BuildDeclRefExpr(D, DType, Loc, Dependent, Dependent, SS); 1079 } 1080 } 1081 } 1082 1083 // We may have found a field within an anonymous union or struct 1084 // (C++ [class.union]). 1085 if (FieldDecl *FD = dyn_cast<FieldDecl>(D)) 1086 if (cast<RecordDecl>(FD->getDeclContext())->isAnonymousStructOrUnion()) 1087 return BuildAnonymousStructUnionMemberReference(Loc, FD); 1088 1089 if (CXXMethodDecl *MD = dyn_cast<CXXMethodDecl>(CurContext)) { 1090 if (!MD->isStatic()) { 1091 // C++ [class.mfct.nonstatic]p2: 1092 // [...] if name lookup (3.4.1) resolves the name in the 1093 // id-expression to a nonstatic nontype member of class X or of 1094 // a base class of X, the id-expression is transformed into a 1095 // class member access expression (5.2.5) using (*this) (9.3.2) 1096 // as the postfix-expression to the left of the '.' operator. 1097 DeclContext *Ctx = 0; 1098 QualType MemberType; 1099 if (FieldDecl *FD = dyn_cast<FieldDecl>(D)) { 1100 Ctx = FD->getDeclContext(); 1101 MemberType = FD->getType(); 1102 1103 if (const ReferenceType *RefType = MemberType->getAs<ReferenceType>()) 1104 MemberType = RefType->getPointeeType(); 1105 else if (!FD->isMutable()) { 1106 unsigned combinedQualifiers 1107 = MemberType.getCVRQualifiers() | MD->getTypeQualifiers(); 1108 MemberType = MemberType.getQualifiedType(combinedQualifiers); 1109 } 1110 } else if (CXXMethodDecl *Method = dyn_cast<CXXMethodDecl>(D)) { 1111 if (!Method->isStatic()) { 1112 Ctx = Method->getParent(); 1113 MemberType = Method->getType(); 1114 } 1115 } else if (OverloadedFunctionDecl *Ovl 1116 = dyn_cast<OverloadedFunctionDecl>(D)) { 1117 for (OverloadedFunctionDecl::function_iterator 1118 Func = Ovl->function_begin(), 1119 FuncEnd = Ovl->function_end(); 1120 Func != FuncEnd; ++Func) { 1121 if (CXXMethodDecl *DMethod = dyn_cast<CXXMethodDecl>(*Func)) 1122 if (!DMethod->isStatic()) { 1123 Ctx = Ovl->getDeclContext(); 1124 MemberType = Context.OverloadTy; 1125 break; 1126 } 1127 } 1128 } 1129 1130 if (Ctx && Ctx->isRecord()) { 1131 QualType CtxType = Context.getTagDeclType(cast<CXXRecordDecl>(Ctx)); 1132 QualType ThisType = Context.getTagDeclType(MD->getParent()); 1133 if ((Context.getCanonicalType(CtxType) 1134 == Context.getCanonicalType(ThisType)) || 1135 IsDerivedFrom(ThisType, CtxType)) { 1136 // Build the implicit member access expression. 1137 Expr *This = new (Context) CXXThisExpr(SourceLocation(), 1138 MD->getThisType(Context)); 1139 MarkDeclarationReferenced(Loc, D); 1140 if (PerformObjectMemberConversion(This, D)) 1141 return ExprError(); 1142 if (DiagnoseUseOfDecl(D, Loc)) 1143 return ExprError(); 1144 return Owned(new (Context) MemberExpr(This, true, D, 1145 Loc, MemberType)); 1146 } 1147 } 1148 } 1149 } 1150 1151 if (FieldDecl *FD = dyn_cast<FieldDecl>(D)) { 1152 if (CXXMethodDecl *MD = dyn_cast<CXXMethodDecl>(CurContext)) { 1153 if (MD->isStatic()) 1154 // "invalid use of member 'x' in static member function" 1155 return ExprError(Diag(Loc,diag::err_invalid_member_use_in_static_method) 1156 << FD->getDeclName()); 1157 } 1158 1159 // Any other ways we could have found the field in a well-formed 1160 // program would have been turned into implicit member expressions 1161 // above. 1162 return ExprError(Diag(Loc, diag::err_invalid_non_static_member_use) 1163 << FD->getDeclName()); 1164 } 1165 1166 if (isa<TypedefDecl>(D)) 1167 return ExprError(Diag(Loc, diag::err_unexpected_typedef) << Name); 1168 if (isa<ObjCInterfaceDecl>(D)) 1169 return ExprError(Diag(Loc, diag::err_unexpected_interface) << Name); 1170 if (isa<NamespaceDecl>(D)) 1171 return ExprError(Diag(Loc, diag::err_unexpected_namespace) << Name); 1172 1173 // Make the DeclRefExpr or BlockDeclRefExpr for the decl. 1174 if (OverloadedFunctionDecl *Ovl = dyn_cast<OverloadedFunctionDecl>(D)) 1175 return BuildDeclRefExpr(Ovl, Context.OverloadTy, Loc, 1176 false, false, SS); 1177 else if (TemplateDecl *Template = dyn_cast<TemplateDecl>(D)) 1178 return BuildDeclRefExpr(Template, Context.OverloadTy, Loc, 1179 false, false, SS); 1180 ValueDecl *VD = cast<ValueDecl>(D); 1181 1182 // Check whether this declaration can be used. Note that we suppress 1183 // this check when we're going to perform argument-dependent lookup 1184 // on this function name, because this might not be the function 1185 // that overload resolution actually selects. 1186 bool ADL = getLangOptions().CPlusPlus && (!SS || !SS->isSet()) && 1187 HasTrailingLParen; 1188 if (!(ADL && isa<FunctionDecl>(VD)) && DiagnoseUseOfDecl(VD, Loc)) 1189 return ExprError(); 1190 1191 // Only create DeclRefExpr's for valid Decl's. 1192 if (VD->isInvalidDecl()) 1193 return ExprError(); 1194 1195 // If the identifier reference is inside a block, and it refers to a value 1196 // that is outside the block, create a BlockDeclRefExpr instead of a 1197 // DeclRefExpr. This ensures the value is treated as a copy-in snapshot when 1198 // the block is formed. 1199 // 1200 // We do not do this for things like enum constants, global variables, etc, 1201 // as they do not get snapshotted. 1202 // 1203 if (CurBlock && ShouldSnapshotBlockValueReference(CurBlock, VD)) { 1204 MarkDeclarationReferenced(Loc, VD); 1205 QualType ExprTy = VD->getType().getNonReferenceType(); 1206 // The BlocksAttr indicates the variable is bound by-reference. 1207 if (VD->getAttr<BlocksAttr>()) 1208 return Owned(new (Context) BlockDeclRefExpr(VD, ExprTy, Loc, true)); 1209 // This is to record that a 'const' was actually synthesize and added. 1210 bool constAdded = !ExprTy.isConstQualified(); 1211 // Variable will be bound by-copy, make it const within the closure. 1212 1213 ExprTy.addConst(); 1214 return Owned(new (Context) BlockDeclRefExpr(VD, ExprTy, Loc, false, 1215 constAdded)); 1216 } 1217 // If this reference is not in a block or if the referenced variable is 1218 // within the block, create a normal DeclRefExpr. 1219 1220 bool TypeDependent = false; 1221 bool ValueDependent = false; 1222 if (getLangOptions().CPlusPlus) { 1223 // C++ [temp.dep.expr]p3: 1224 // An id-expression is type-dependent if it contains: 1225 // - an identifier that was declared with a dependent type, 1226 if (VD->getType()->isDependentType()) 1227 TypeDependent = true; 1228 // - FIXME: a template-id that is dependent, 1229 // - a conversion-function-id that specifies a dependent type, 1230 else if (Name.getNameKind() == DeclarationName::CXXConversionFunctionName && 1231 Name.getCXXNameType()->isDependentType()) 1232 TypeDependent = true; 1233 // - a nested-name-specifier that contains a class-name that 1234 // names a dependent type. 1235 else if (SS && !SS->isEmpty()) { 1236 for (DeclContext *DC = computeDeclContext(*SS); 1237 DC; DC = DC->getParent()) { 1238 // FIXME: could stop early at namespace scope. 1239 if (DC->isRecord()) { 1240 CXXRecordDecl *Record = cast<CXXRecordDecl>(DC); 1241 if (Context.getTypeDeclType(Record)->isDependentType()) { 1242 TypeDependent = true; 1243 break; 1244 } 1245 } 1246 } 1247 } 1248 1249 // C++ [temp.dep.constexpr]p2: 1250 // 1251 // An identifier is value-dependent if it is: 1252 // - a name declared with a dependent type, 1253 if (TypeDependent) 1254 ValueDependent = true; 1255 // - the name of a non-type template parameter, 1256 else if (isa<NonTypeTemplateParmDecl>(VD)) 1257 ValueDependent = true; 1258 // - a constant with integral or enumeration type and is 1259 // initialized with an expression that is value-dependent 1260 else if (const VarDecl *Dcl = dyn_cast<VarDecl>(VD)) { 1261 if (Dcl->getType().getCVRQualifiers() == QualType::Const && 1262 Dcl->getInit()) { 1263 ValueDependent = Dcl->getInit()->isValueDependent(); 1264 } 1265 } 1266 } 1267 1268 return BuildDeclRefExpr(VD, VD->getType().getNonReferenceType(), Loc, 1269 TypeDependent, ValueDependent, SS); 1270} 1271 1272Sema::OwningExprResult Sema::ActOnPredefinedExpr(SourceLocation Loc, 1273 tok::TokenKind Kind) { 1274 PredefinedExpr::IdentType IT; 1275 1276 switch (Kind) { 1277 default: assert(0 && "Unknown simple primary expr!"); 1278 case tok::kw___func__: IT = PredefinedExpr::Func; break; // [C99 6.4.2.2] 1279 case tok::kw___FUNCTION__: IT = PredefinedExpr::Function; break; 1280 case tok::kw___PRETTY_FUNCTION__: IT = PredefinedExpr::PrettyFunction; break; 1281 } 1282 1283 // Pre-defined identifiers are of type char[x], where x is the length of the 1284 // string. 1285 unsigned Length; 1286 if (FunctionDecl *FD = getCurFunctionDecl()) 1287 Length = FD->getIdentifier()->getLength(); 1288 else if (ObjCMethodDecl *MD = getCurMethodDecl()) 1289 Length = MD->getSynthesizedMethodSize(); 1290 else { 1291 Diag(Loc, diag::ext_predef_outside_function); 1292 // __PRETTY_FUNCTION__ -> "top level", the others produce an empty string. 1293 Length = IT == PredefinedExpr::PrettyFunction ? strlen("top level") : 0; 1294 } 1295 1296 1297 llvm::APInt LengthI(32, Length + 1); 1298 QualType ResTy = Context.CharTy.getQualifiedType(QualType::Const); 1299 ResTy = Context.getConstantArrayType(ResTy, LengthI, ArrayType::Normal, 0); 1300 return Owned(new (Context) PredefinedExpr(Loc, ResTy, IT)); 1301} 1302 1303Sema::OwningExprResult Sema::ActOnCharacterConstant(const Token &Tok) { 1304 llvm::SmallString<16> CharBuffer; 1305 CharBuffer.resize(Tok.getLength()); 1306 const char *ThisTokBegin = &CharBuffer[0]; 1307 unsigned ActualLength = PP.getSpelling(Tok, ThisTokBegin); 1308 1309 CharLiteralParser Literal(ThisTokBegin, ThisTokBegin+ActualLength, 1310 Tok.getLocation(), PP); 1311 if (Literal.hadError()) 1312 return ExprError(); 1313 1314 QualType type = getLangOptions().CPlusPlus ? Context.CharTy : Context.IntTy; 1315 1316 return Owned(new (Context) CharacterLiteral(Literal.getValue(), 1317 Literal.isWide(), 1318 type, Tok.getLocation())); 1319} 1320 1321Action::OwningExprResult Sema::ActOnNumericConstant(const Token &Tok) { 1322 // Fast path for a single digit (which is quite common). A single digit 1323 // cannot have a trigraph, escaped newline, radix prefix, or type suffix. 1324 if (Tok.getLength() == 1) { 1325 const char Val = PP.getSpellingOfSingleCharacterNumericConstant(Tok); 1326 unsigned IntSize = Context.Target.getIntWidth(); 1327 return Owned(new (Context) IntegerLiteral(llvm::APInt(IntSize, Val-'0'), 1328 Context.IntTy, Tok.getLocation())); 1329 } 1330 1331 llvm::SmallString<512> IntegerBuffer; 1332 // Add padding so that NumericLiteralParser can overread by one character. 1333 IntegerBuffer.resize(Tok.getLength()+1); 1334 const char *ThisTokBegin = &IntegerBuffer[0]; 1335 1336 // Get the spelling of the token, which eliminates trigraphs, etc. 1337 unsigned ActualLength = PP.getSpelling(Tok, ThisTokBegin); 1338 1339 NumericLiteralParser Literal(ThisTokBegin, ThisTokBegin+ActualLength, 1340 Tok.getLocation(), PP); 1341 if (Literal.hadError) 1342 return ExprError(); 1343 1344 Expr *Res; 1345 1346 if (Literal.isFloatingLiteral()) { 1347 QualType Ty; 1348 if (Literal.isFloat) 1349 Ty = Context.FloatTy; 1350 else if (!Literal.isLong) 1351 Ty = Context.DoubleTy; 1352 else 1353 Ty = Context.LongDoubleTy; 1354 1355 const llvm::fltSemantics &Format = Context.getFloatTypeSemantics(Ty); 1356 1357 // isExact will be set by GetFloatValue(). 1358 bool isExact = false; 1359 llvm::APFloat Val = Literal.GetFloatValue(Format, &isExact); 1360 Res = new (Context) FloatingLiteral(Val, isExact, Ty, Tok.getLocation()); 1361 1362 } else if (!Literal.isIntegerLiteral()) { 1363 return ExprError(); 1364 } else { 1365 QualType Ty; 1366 1367 // long long is a C99 feature. 1368 if (!getLangOptions().C99 && !getLangOptions().CPlusPlus0x && 1369 Literal.isLongLong) 1370 Diag(Tok.getLocation(), diag::ext_longlong); 1371 1372 // Get the value in the widest-possible width. 1373 llvm::APInt ResultVal(Context.Target.getIntMaxTWidth(), 0); 1374 1375 if (Literal.GetIntegerValue(ResultVal)) { 1376 // If this value didn't fit into uintmax_t, warn and force to ull. 1377 Diag(Tok.getLocation(), diag::warn_integer_too_large); 1378 Ty = Context.UnsignedLongLongTy; 1379 assert(Context.getTypeSize(Ty) == ResultVal.getBitWidth() && 1380 "long long is not intmax_t?"); 1381 } else { 1382 // If this value fits into a ULL, try to figure out what else it fits into 1383 // according to the rules of C99 6.4.4.1p5. 1384 1385 // Octal, Hexadecimal, and integers with a U suffix are allowed to 1386 // be an unsigned int. 1387 bool AllowUnsigned = Literal.isUnsigned || Literal.getRadix() != 10; 1388 1389 // Check from smallest to largest, picking the smallest type we can. 1390 unsigned Width = 0; 1391 if (!Literal.isLong && !Literal.isLongLong) { 1392 // Are int/unsigned possibilities? 1393 unsigned IntSize = Context.Target.getIntWidth(); 1394 1395 // Does it fit in a unsigned int? 1396 if (ResultVal.isIntN(IntSize)) { 1397 // Does it fit in a signed int? 1398 if (!Literal.isUnsigned && ResultVal[IntSize-1] == 0) 1399 Ty = Context.IntTy; 1400 else if (AllowUnsigned) 1401 Ty = Context.UnsignedIntTy; 1402 Width = IntSize; 1403 } 1404 } 1405 1406 // Are long/unsigned long possibilities? 1407 if (Ty.isNull() && !Literal.isLongLong) { 1408 unsigned LongSize = Context.Target.getLongWidth(); 1409 1410 // Does it fit in a unsigned long? 1411 if (ResultVal.isIntN(LongSize)) { 1412 // Does it fit in a signed long? 1413 if (!Literal.isUnsigned && ResultVal[LongSize-1] == 0) 1414 Ty = Context.LongTy; 1415 else if (AllowUnsigned) 1416 Ty = Context.UnsignedLongTy; 1417 Width = LongSize; 1418 } 1419 } 1420 1421 // Finally, check long long if needed. 1422 if (Ty.isNull()) { 1423 unsigned LongLongSize = Context.Target.getLongLongWidth(); 1424 1425 // Does it fit in a unsigned long long? 1426 if (ResultVal.isIntN(LongLongSize)) { 1427 // Does it fit in a signed long long? 1428 if (!Literal.isUnsigned && ResultVal[LongLongSize-1] == 0) 1429 Ty = Context.LongLongTy; 1430 else if (AllowUnsigned) 1431 Ty = Context.UnsignedLongLongTy; 1432 Width = LongLongSize; 1433 } 1434 } 1435 1436 // If we still couldn't decide a type, we probably have something that 1437 // does not fit in a signed long long, but has no U suffix. 1438 if (Ty.isNull()) { 1439 Diag(Tok.getLocation(), diag::warn_integer_too_large_for_signed); 1440 Ty = Context.UnsignedLongLongTy; 1441 Width = Context.Target.getLongLongWidth(); 1442 } 1443 1444 if (ResultVal.getBitWidth() != Width) 1445 ResultVal.trunc(Width); 1446 } 1447 Res = new (Context) IntegerLiteral(ResultVal, Ty, Tok.getLocation()); 1448 } 1449 1450 // If this is an imaginary literal, create the ImaginaryLiteral wrapper. 1451 if (Literal.isImaginary) 1452 Res = new (Context) ImaginaryLiteral(Res, 1453 Context.getComplexType(Res->getType())); 1454 1455 return Owned(Res); 1456} 1457 1458Action::OwningExprResult Sema::ActOnParenExpr(SourceLocation L, 1459 SourceLocation R, ExprArg Val) { 1460 Expr *E = Val.takeAs<Expr>(); 1461 assert((E != 0) && "ActOnParenExpr() missing expr"); 1462 return Owned(new (Context) ParenExpr(L, R, E)); 1463} 1464 1465/// The UsualUnaryConversions() function is *not* called by this routine. 1466/// See C99 6.3.2.1p[2-4] for more details. 1467bool Sema::CheckSizeOfAlignOfOperand(QualType exprType, 1468 SourceLocation OpLoc, 1469 const SourceRange &ExprRange, 1470 bool isSizeof) { 1471 if (exprType->isDependentType()) 1472 return false; 1473 1474 // C99 6.5.3.4p1: 1475 if (isa<FunctionType>(exprType)) { 1476 // alignof(function) is allowed as an extension. 1477 if (isSizeof) 1478 Diag(OpLoc, diag::ext_sizeof_function_type) << ExprRange; 1479 return false; 1480 } 1481 1482 // Allow sizeof(void)/alignof(void) as an extension. 1483 if (exprType->isVoidType()) { 1484 Diag(OpLoc, diag::ext_sizeof_void_type) 1485 << (isSizeof ? "sizeof" : "__alignof") << ExprRange; 1486 return false; 1487 } 1488 1489 if (RequireCompleteType(OpLoc, exprType, 1490 isSizeof ? diag::err_sizeof_incomplete_type : 1491 diag::err_alignof_incomplete_type, 1492 ExprRange)) 1493 return true; 1494 1495 // Reject sizeof(interface) and sizeof(interface<proto>) in 64-bit mode. 1496 if (LangOpts.ObjCNonFragileABI && exprType->isObjCInterfaceType()) { 1497 Diag(OpLoc, diag::err_sizeof_nonfragile_interface) 1498 << exprType << isSizeof << ExprRange; 1499 return true; 1500 } 1501 1502 return false; 1503} 1504 1505bool Sema::CheckAlignOfExpr(Expr *E, SourceLocation OpLoc, 1506 const SourceRange &ExprRange) { 1507 E = E->IgnoreParens(); 1508 1509 // alignof decl is always ok. 1510 if (isa<DeclRefExpr>(E)) 1511 return false; 1512 1513 // Cannot know anything else if the expression is dependent. 1514 if (E->isTypeDependent()) 1515 return false; 1516 1517 if (E->getBitField()) { 1518 Diag(OpLoc, diag::err_sizeof_alignof_bitfield) << 1 << ExprRange; 1519 return true; 1520 } 1521 1522 // Alignment of a field access is always okay, so long as it isn't a 1523 // bit-field. 1524 if (MemberExpr *ME = dyn_cast<MemberExpr>(E)) 1525 if (isa<FieldDecl>(ME->getMemberDecl())) 1526 return false; 1527 1528 return CheckSizeOfAlignOfOperand(E->getType(), OpLoc, ExprRange, false); 1529} 1530 1531/// \brief Build a sizeof or alignof expression given a type operand. 1532Action::OwningExprResult 1533Sema::CreateSizeOfAlignOfExpr(QualType T, SourceLocation OpLoc, 1534 bool isSizeOf, SourceRange R) { 1535 if (T.isNull()) 1536 return ExprError(); 1537 1538 if (!T->isDependentType() && 1539 CheckSizeOfAlignOfOperand(T, OpLoc, R, isSizeOf)) 1540 return ExprError(); 1541 1542 // C99 6.5.3.4p4: the type (an unsigned integer type) is size_t. 1543 return Owned(new (Context) SizeOfAlignOfExpr(isSizeOf, T, 1544 Context.getSizeType(), OpLoc, 1545 R.getEnd())); 1546} 1547 1548/// \brief Build a sizeof or alignof expression given an expression 1549/// operand. 1550Action::OwningExprResult 1551Sema::CreateSizeOfAlignOfExpr(Expr *E, SourceLocation OpLoc, 1552 bool isSizeOf, SourceRange R) { 1553 // Verify that the operand is valid. 1554 bool isInvalid = false; 1555 if (E->isTypeDependent()) { 1556 // Delay type-checking for type-dependent expressions. 1557 } else if (!isSizeOf) { 1558 isInvalid = CheckAlignOfExpr(E, OpLoc, R); 1559 } else if (E->getBitField()) { // C99 6.5.3.4p1. 1560 Diag(OpLoc, diag::err_sizeof_alignof_bitfield) << 0; 1561 isInvalid = true; 1562 } else { 1563 isInvalid = CheckSizeOfAlignOfOperand(E->getType(), OpLoc, R, true); 1564 } 1565 1566 if (isInvalid) 1567 return ExprError(); 1568 1569 // C99 6.5.3.4p4: the type (an unsigned integer type) is size_t. 1570 return Owned(new (Context) SizeOfAlignOfExpr(isSizeOf, E, 1571 Context.getSizeType(), OpLoc, 1572 R.getEnd())); 1573} 1574 1575/// ActOnSizeOfAlignOfExpr - Handle @c sizeof(type) and @c sizeof @c expr and 1576/// the same for @c alignof and @c __alignof 1577/// Note that the ArgRange is invalid if isType is false. 1578Action::OwningExprResult 1579Sema::ActOnSizeOfAlignOfExpr(SourceLocation OpLoc, bool isSizeof, bool isType, 1580 void *TyOrEx, const SourceRange &ArgRange) { 1581 // If error parsing type, ignore. 1582 if (TyOrEx == 0) return ExprError(); 1583 1584 if (isType) { 1585 QualType ArgTy = QualType::getFromOpaquePtr(TyOrEx); 1586 return CreateSizeOfAlignOfExpr(ArgTy, OpLoc, isSizeof, ArgRange); 1587 } 1588 1589 // Get the end location. 1590 Expr *ArgEx = (Expr *)TyOrEx; 1591 Action::OwningExprResult Result 1592 = CreateSizeOfAlignOfExpr(ArgEx, OpLoc, isSizeof, ArgEx->getSourceRange()); 1593 1594 if (Result.isInvalid()) 1595 DeleteExpr(ArgEx); 1596 1597 return move(Result); 1598} 1599 1600QualType Sema::CheckRealImagOperand(Expr *&V, SourceLocation Loc, bool isReal) { 1601 if (V->isTypeDependent()) 1602 return Context.DependentTy; 1603 1604 // These operators return the element type of a complex type. 1605 if (const ComplexType *CT = V->getType()->getAsComplexType()) 1606 return CT->getElementType(); 1607 1608 // Otherwise they pass through real integer and floating point types here. 1609 if (V->getType()->isArithmeticType()) 1610 return V->getType(); 1611 1612 // Reject anything else. 1613 Diag(Loc, diag::err_realimag_invalid_type) << V->getType() 1614 << (isReal ? "__real" : "__imag"); 1615 return QualType(); 1616} 1617 1618 1619 1620Action::OwningExprResult 1621Sema::ActOnPostfixUnaryOp(Scope *S, SourceLocation OpLoc, 1622 tok::TokenKind Kind, ExprArg Input) { 1623 Expr *Arg = (Expr *)Input.get(); 1624 1625 UnaryOperator::Opcode Opc; 1626 switch (Kind) { 1627 default: assert(0 && "Unknown unary op!"); 1628 case tok::plusplus: Opc = UnaryOperator::PostInc; break; 1629 case tok::minusminus: Opc = UnaryOperator::PostDec; break; 1630 } 1631 1632 if (getLangOptions().CPlusPlus && 1633 (Arg->getType()->isRecordType() || Arg->getType()->isEnumeralType())) { 1634 // Which overloaded operator? 1635 OverloadedOperatorKind OverOp = 1636 (Opc == UnaryOperator::PostInc)? OO_PlusPlus : OO_MinusMinus; 1637 1638 // C++ [over.inc]p1: 1639 // 1640 // [...] If the function is a member function with one 1641 // parameter (which shall be of type int) or a non-member 1642 // function with two parameters (the second of which shall be 1643 // of type int), it defines the postfix increment operator ++ 1644 // for objects of that type. When the postfix increment is 1645 // called as a result of using the ++ operator, the int 1646 // argument will have value zero. 1647 Expr *Args[2] = { 1648 Arg, 1649 new (Context) IntegerLiteral(llvm::APInt(Context.Target.getIntWidth(), 0, 1650 /*isSigned=*/true), Context.IntTy, SourceLocation()) 1651 }; 1652 1653 // Build the candidate set for overloading 1654 OverloadCandidateSet CandidateSet; 1655 AddOperatorCandidates(OverOp, S, OpLoc, Args, 2, CandidateSet); 1656 1657 // Perform overload resolution. 1658 OverloadCandidateSet::iterator Best; 1659 switch (BestViableFunction(CandidateSet, OpLoc, Best)) { 1660 case OR_Success: { 1661 // We found a built-in operator or an overloaded operator. 1662 FunctionDecl *FnDecl = Best->Function; 1663 1664 if (FnDecl) { 1665 // We matched an overloaded operator. Build a call to that 1666 // operator. 1667 1668 // Convert the arguments. 1669 if (CXXMethodDecl *Method = dyn_cast<CXXMethodDecl>(FnDecl)) { 1670 if (PerformObjectArgumentInitialization(Arg, Method)) 1671 return ExprError(); 1672 } else { 1673 // Convert the arguments. 1674 if (PerformCopyInitialization(Arg, 1675 FnDecl->getParamDecl(0)->getType(), 1676 "passing")) 1677 return ExprError(); 1678 } 1679 1680 // Determine the result type 1681 QualType ResultTy 1682 = FnDecl->getType()->getAsFunctionType()->getResultType(); 1683 ResultTy = ResultTy.getNonReferenceType(); 1684 1685 // Build the actual expression node. 1686 Expr *FnExpr = new (Context) DeclRefExpr(FnDecl, FnDecl->getType(), 1687 SourceLocation()); 1688 UsualUnaryConversions(FnExpr); 1689 1690 Input.release(); 1691 Args[0] = Arg; 1692 return Owned(new (Context) CXXOperatorCallExpr(Context, OverOp, FnExpr, 1693 Args, 2, ResultTy, 1694 OpLoc)); 1695 } else { 1696 // We matched a built-in operator. Convert the arguments, then 1697 // break out so that we will build the appropriate built-in 1698 // operator node. 1699 if (PerformCopyInitialization(Arg, Best->BuiltinTypes.ParamTypes[0], 1700 "passing")) 1701 return ExprError(); 1702 1703 break; 1704 } 1705 } 1706 1707 case OR_No_Viable_Function: 1708 // No viable function; fall through to handling this as a 1709 // built-in operator, which will produce an error message for us. 1710 break; 1711 1712 case OR_Ambiguous: 1713 Diag(OpLoc, diag::err_ovl_ambiguous_oper) 1714 << UnaryOperator::getOpcodeStr(Opc) 1715 << Arg->getSourceRange(); 1716 PrintOverloadCandidates(CandidateSet, /*OnlyViable=*/true); 1717 return ExprError(); 1718 1719 case OR_Deleted: 1720 Diag(OpLoc, diag::err_ovl_deleted_oper) 1721 << Best->Function->isDeleted() 1722 << UnaryOperator::getOpcodeStr(Opc) 1723 << Arg->getSourceRange(); 1724 PrintOverloadCandidates(CandidateSet, /*OnlyViable=*/true); 1725 return ExprError(); 1726 } 1727 1728 // Either we found no viable overloaded operator or we matched a 1729 // built-in operator. In either case, fall through to trying to 1730 // build a built-in operation. 1731 } 1732 1733 Input.release(); 1734 Input = Arg; 1735 return CreateBuiltinUnaryOp(OpLoc, Opc, move(Input)); 1736} 1737 1738Action::OwningExprResult 1739Sema::ActOnArraySubscriptExpr(Scope *S, ExprArg Base, SourceLocation LLoc, 1740 ExprArg Idx, SourceLocation RLoc) { 1741 Expr *LHSExp = static_cast<Expr*>(Base.get()), 1742 *RHSExp = static_cast<Expr*>(Idx.get()); 1743 1744 if (getLangOptions().CPlusPlus && 1745 (LHSExp->isTypeDependent() || RHSExp->isTypeDependent())) { 1746 Base.release(); 1747 Idx.release(); 1748 return Owned(new (Context) ArraySubscriptExpr(LHSExp, RHSExp, 1749 Context.DependentTy, RLoc)); 1750 } 1751 1752 if (getLangOptions().CPlusPlus && 1753 (LHSExp->getType()->isRecordType() || 1754 LHSExp->getType()->isEnumeralType() || 1755 RHSExp->getType()->isRecordType() || 1756 RHSExp->getType()->isEnumeralType())) { 1757 // Add the appropriate overloaded operators (C++ [over.match.oper]) 1758 // to the candidate set. 1759 OverloadCandidateSet CandidateSet; 1760 Expr *Args[2] = { LHSExp, RHSExp }; 1761 AddOperatorCandidates(OO_Subscript, S, LLoc, Args, 2, CandidateSet, 1762 SourceRange(LLoc, RLoc)); 1763 1764 // Perform overload resolution. 1765 OverloadCandidateSet::iterator Best; 1766 switch (BestViableFunction(CandidateSet, LLoc, Best)) { 1767 case OR_Success: { 1768 // We found a built-in operator or an overloaded operator. 1769 FunctionDecl *FnDecl = Best->Function; 1770 1771 if (FnDecl) { 1772 // We matched an overloaded operator. Build a call to that 1773 // operator. 1774 1775 // Convert the arguments. 1776 if (CXXMethodDecl *Method = dyn_cast<CXXMethodDecl>(FnDecl)) { 1777 if (PerformObjectArgumentInitialization(LHSExp, Method) || 1778 PerformCopyInitialization(RHSExp, 1779 FnDecl->getParamDecl(0)->getType(), 1780 "passing")) 1781 return ExprError(); 1782 } else { 1783 // Convert the arguments. 1784 if (PerformCopyInitialization(LHSExp, 1785 FnDecl->getParamDecl(0)->getType(), 1786 "passing") || 1787 PerformCopyInitialization(RHSExp, 1788 FnDecl->getParamDecl(1)->getType(), 1789 "passing")) 1790 return ExprError(); 1791 } 1792 1793 // Determine the result type 1794 QualType ResultTy 1795 = FnDecl->getType()->getAsFunctionType()->getResultType(); 1796 ResultTy = ResultTy.getNonReferenceType(); 1797 1798 // Build the actual expression node. 1799 Expr *FnExpr = new (Context) DeclRefExpr(FnDecl, FnDecl->getType(), 1800 SourceLocation()); 1801 UsualUnaryConversions(FnExpr); 1802 1803 Base.release(); 1804 Idx.release(); 1805 Args[0] = LHSExp; 1806 Args[1] = RHSExp; 1807 return Owned(new (Context) CXXOperatorCallExpr(Context, OO_Subscript, 1808 FnExpr, Args, 2, 1809 ResultTy, LLoc)); 1810 } else { 1811 // We matched a built-in operator. Convert the arguments, then 1812 // break out so that we will build the appropriate built-in 1813 // operator node. 1814 if (PerformCopyInitialization(LHSExp, Best->BuiltinTypes.ParamTypes[0], 1815 "passing") || 1816 PerformCopyInitialization(RHSExp, Best->BuiltinTypes.ParamTypes[1], 1817 "passing")) 1818 return ExprError(); 1819 1820 break; 1821 } 1822 } 1823 1824 case OR_No_Viable_Function: 1825 // No viable function; fall through to handling this as a 1826 // built-in operator, which will produce an error message for us. 1827 break; 1828 1829 case OR_Ambiguous: 1830 Diag(LLoc, diag::err_ovl_ambiguous_oper) 1831 << "[]" 1832 << LHSExp->getSourceRange() << RHSExp->getSourceRange(); 1833 PrintOverloadCandidates(CandidateSet, /*OnlyViable=*/true); 1834 return ExprError(); 1835 1836 case OR_Deleted: 1837 Diag(LLoc, diag::err_ovl_deleted_oper) 1838 << Best->Function->isDeleted() 1839 << "[]" 1840 << LHSExp->getSourceRange() << RHSExp->getSourceRange(); 1841 PrintOverloadCandidates(CandidateSet, /*OnlyViable=*/true); 1842 return ExprError(); 1843 } 1844 1845 // Either we found no viable overloaded operator or we matched a 1846 // built-in operator. In either case, fall through to trying to 1847 // build a built-in operation. 1848 } 1849 1850 // Perform default conversions. 1851 DefaultFunctionArrayConversion(LHSExp); 1852 DefaultFunctionArrayConversion(RHSExp); 1853 1854 QualType LHSTy = LHSExp->getType(), RHSTy = RHSExp->getType(); 1855 1856 // C99 6.5.2.1p2: the expression e1[e2] is by definition precisely equivalent 1857 // to the expression *((e1)+(e2)). This means the array "Base" may actually be 1858 // in the subscript position. As a result, we need to derive the array base 1859 // and index from the expression types. 1860 Expr *BaseExpr, *IndexExpr; 1861 QualType ResultType; 1862 if (LHSTy->isDependentType() || RHSTy->isDependentType()) { 1863 BaseExpr = LHSExp; 1864 IndexExpr = RHSExp; 1865 ResultType = Context.DependentTy; 1866 } else if (const PointerType *PTy = LHSTy->getAs<PointerType>()) { 1867 BaseExpr = LHSExp; 1868 IndexExpr = RHSExp; 1869 ResultType = PTy->getPointeeType(); 1870 } else if (const PointerType *PTy = RHSTy->getAs<PointerType>()) { 1871 // Handle the uncommon case of "123[Ptr]". 1872 BaseExpr = RHSExp; 1873 IndexExpr = LHSExp; 1874 ResultType = PTy->getPointeeType(); 1875 } else if (const ObjCObjectPointerType *PTy = 1876 LHSTy->getAsObjCObjectPointerType()) { 1877 BaseExpr = LHSExp; 1878 IndexExpr = RHSExp; 1879 ResultType = PTy->getPointeeType(); 1880 } else if (const ObjCObjectPointerType *PTy = 1881 RHSTy->getAsObjCObjectPointerType()) { 1882 // Handle the uncommon case of "123[Ptr]". 1883 BaseExpr = RHSExp; 1884 IndexExpr = LHSExp; 1885 ResultType = PTy->getPointeeType(); 1886 } else if (const VectorType *VTy = LHSTy->getAsVectorType()) { 1887 BaseExpr = LHSExp; // vectors: V[123] 1888 IndexExpr = RHSExp; 1889 1890 // FIXME: need to deal with const... 1891 ResultType = VTy->getElementType(); 1892 } else if (LHSTy->isArrayType()) { 1893 // If we see an array that wasn't promoted by 1894 // DefaultFunctionArrayConversion, it must be an array that 1895 // wasn't promoted because of the C90 rule that doesn't 1896 // allow promoting non-lvalue arrays. Warn, then 1897 // force the promotion here. 1898 Diag(LHSExp->getLocStart(), diag::ext_subscript_non_lvalue) << 1899 LHSExp->getSourceRange(); 1900 ImpCastExprToType(LHSExp, Context.getArrayDecayedType(LHSTy)); 1901 LHSTy = LHSExp->getType(); 1902 1903 BaseExpr = LHSExp; 1904 IndexExpr = RHSExp; 1905 ResultType = LHSTy->getAs<PointerType>()->getPointeeType(); 1906 } else if (RHSTy->isArrayType()) { 1907 // Same as previous, except for 123[f().a] case 1908 Diag(RHSExp->getLocStart(), diag::ext_subscript_non_lvalue) << 1909 RHSExp->getSourceRange(); 1910 ImpCastExprToType(RHSExp, Context.getArrayDecayedType(RHSTy)); 1911 RHSTy = RHSExp->getType(); 1912 1913 BaseExpr = RHSExp; 1914 IndexExpr = LHSExp; 1915 ResultType = RHSTy->getAs<PointerType>()->getPointeeType(); 1916 } else { 1917 return ExprError(Diag(LLoc, diag::err_typecheck_subscript_value) 1918 << LHSExp->getSourceRange() << RHSExp->getSourceRange()); 1919 } 1920 // C99 6.5.2.1p1 1921 if (!IndexExpr->getType()->isIntegerType() && !IndexExpr->isTypeDependent()) 1922 return ExprError(Diag(LLoc, diag::err_typecheck_subscript_not_integer) 1923 << IndexExpr->getSourceRange()); 1924 1925 // C99 6.5.2.1p1: "shall have type "pointer to *object* type". Similarly, 1926 // C++ [expr.sub]p1: The type "T" shall be a completely-defined object 1927 // type. Note that Functions are not objects, and that (in C99 parlance) 1928 // incomplete types are not object types. 1929 if (ResultType->isFunctionType()) { 1930 Diag(BaseExpr->getLocStart(), diag::err_subscript_function_type) 1931 << ResultType << BaseExpr->getSourceRange(); 1932 return ExprError(); 1933 } 1934 1935 if (!ResultType->isDependentType() && 1936 RequireCompleteType(LLoc, ResultType, diag::err_subscript_incomplete_type, 1937 BaseExpr->getSourceRange())) 1938 return ExprError(); 1939 1940 // Diagnose bad cases where we step over interface counts. 1941 if (ResultType->isObjCInterfaceType() && LangOpts.ObjCNonFragileABI) { 1942 Diag(LLoc, diag::err_subscript_nonfragile_interface) 1943 << ResultType << BaseExpr->getSourceRange(); 1944 return ExprError(); 1945 } 1946 1947 Base.release(); 1948 Idx.release(); 1949 return Owned(new (Context) ArraySubscriptExpr(LHSExp, RHSExp, 1950 ResultType, RLoc)); 1951} 1952 1953QualType Sema:: 1954CheckExtVectorComponent(QualType baseType, SourceLocation OpLoc, 1955 IdentifierInfo &CompName, SourceLocation CompLoc) { 1956 const ExtVectorType *vecType = baseType->getAsExtVectorType(); 1957 1958 // The vector accessor can't exceed the number of elements. 1959 const char *compStr = CompName.getName(); 1960 1961 // This flag determines whether or not the component is one of the four 1962 // special names that indicate a subset of exactly half the elements are 1963 // to be selected. 1964 bool HalvingSwizzle = false; 1965 1966 // This flag determines whether or not CompName has an 's' char prefix, 1967 // indicating that it is a string of hex values to be used as vector indices. 1968 bool HexSwizzle = *compStr == 's' || *compStr == 'S'; 1969 1970 // Check that we've found one of the special components, or that the component 1971 // names must come from the same set. 1972 if (!strcmp(compStr, "hi") || !strcmp(compStr, "lo") || 1973 !strcmp(compStr, "even") || !strcmp(compStr, "odd")) { 1974 HalvingSwizzle = true; 1975 } else if (vecType->getPointAccessorIdx(*compStr) != -1) { 1976 do 1977 compStr++; 1978 while (*compStr && vecType->getPointAccessorIdx(*compStr) != -1); 1979 } else if (HexSwizzle || vecType->getNumericAccessorIdx(*compStr) != -1) { 1980 do 1981 compStr++; 1982 while (*compStr && vecType->getNumericAccessorIdx(*compStr) != -1); 1983 } 1984 1985 if (!HalvingSwizzle && *compStr) { 1986 // We didn't get to the end of the string. This means the component names 1987 // didn't come from the same set *or* we encountered an illegal name. 1988 Diag(OpLoc, diag::err_ext_vector_component_name_illegal) 1989 << std::string(compStr,compStr+1) << SourceRange(CompLoc); 1990 return QualType(); 1991 } 1992 1993 // Ensure no component accessor exceeds the width of the vector type it 1994 // operates on. 1995 if (!HalvingSwizzle) { 1996 compStr = CompName.getName(); 1997 1998 if (HexSwizzle) 1999 compStr++; 2000 2001 while (*compStr) { 2002 if (!vecType->isAccessorWithinNumElements(*compStr++)) { 2003 Diag(OpLoc, diag::err_ext_vector_component_exceeds_length) 2004 << baseType << SourceRange(CompLoc); 2005 return QualType(); 2006 } 2007 } 2008 } 2009 2010 // If this is a halving swizzle, verify that the base type has an even 2011 // number of elements. 2012 if (HalvingSwizzle && (vecType->getNumElements() & 1U)) { 2013 Diag(OpLoc, diag::err_ext_vector_component_requires_even) 2014 << baseType << SourceRange(CompLoc); 2015 return QualType(); 2016 } 2017 2018 // The component accessor looks fine - now we need to compute the actual type. 2019 // The vector type is implied by the component accessor. For example, 2020 // vec4.b is a float, vec4.xy is a vec2, vec4.rgb is a vec3, etc. 2021 // vec4.s0 is a float, vec4.s23 is a vec3, etc. 2022 // vec4.hi, vec4.lo, vec4.e, and vec4.o all return vec2. 2023 unsigned CompSize = HalvingSwizzle ? vecType->getNumElements() / 2 2024 : CompName.getLength(); 2025 if (HexSwizzle) 2026 CompSize--; 2027 2028 if (CompSize == 1) 2029 return vecType->getElementType(); 2030 2031 QualType VT = Context.getExtVectorType(vecType->getElementType(), CompSize); 2032 // Now look up the TypeDefDecl from the vector type. Without this, 2033 // diagostics look bad. We want extended vector types to appear built-in. 2034 for (unsigned i = 0, E = ExtVectorDecls.size(); i != E; ++i) { 2035 if (ExtVectorDecls[i]->getUnderlyingType() == VT) 2036 return Context.getTypedefType(ExtVectorDecls[i]); 2037 } 2038 return VT; // should never get here (a typedef type should always be found). 2039} 2040 2041static Decl *FindGetterNameDeclFromProtocolList(const ObjCProtocolDecl*PDecl, 2042 IdentifierInfo &Member, 2043 const Selector &Sel, 2044 ASTContext &Context) { 2045 2046 if (ObjCPropertyDecl *PD = PDecl->FindPropertyDeclaration(&Member)) 2047 return PD; 2048 if (ObjCMethodDecl *OMD = PDecl->getInstanceMethod(Sel)) 2049 return OMD; 2050 2051 for (ObjCProtocolDecl::protocol_iterator I = PDecl->protocol_begin(), 2052 E = PDecl->protocol_end(); I != E; ++I) { 2053 if (Decl *D = FindGetterNameDeclFromProtocolList(*I, Member, Sel, 2054 Context)) 2055 return D; 2056 } 2057 return 0; 2058} 2059 2060static Decl *FindGetterNameDecl(const ObjCObjectPointerType *QIdTy, 2061 IdentifierInfo &Member, 2062 const Selector &Sel, 2063 ASTContext &Context) { 2064 // Check protocols on qualified interfaces. 2065 Decl *GDecl = 0; 2066 for (ObjCObjectPointerType::qual_iterator I = QIdTy->qual_begin(), 2067 E = QIdTy->qual_end(); I != E; ++I) { 2068 if (ObjCPropertyDecl *PD = (*I)->FindPropertyDeclaration(&Member)) { 2069 GDecl = PD; 2070 break; 2071 } 2072 // Also must look for a getter name which uses property syntax. 2073 if (ObjCMethodDecl *OMD = (*I)->getInstanceMethod(Sel)) { 2074 GDecl = OMD; 2075 break; 2076 } 2077 } 2078 if (!GDecl) { 2079 for (ObjCObjectPointerType::qual_iterator I = QIdTy->qual_begin(), 2080 E = QIdTy->qual_end(); I != E; ++I) { 2081 // Search in the protocol-qualifier list of current protocol. 2082 GDecl = FindGetterNameDeclFromProtocolList(*I, Member, Sel, Context); 2083 if (GDecl) 2084 return GDecl; 2085 } 2086 } 2087 return GDecl; 2088} 2089 2090/// FindMethodInNestedImplementations - Look up a method in current and 2091/// all base class implementations. 2092/// 2093ObjCMethodDecl *Sema::FindMethodInNestedImplementations( 2094 const ObjCInterfaceDecl *IFace, 2095 const Selector &Sel) { 2096 ObjCMethodDecl *Method = 0; 2097 if (ObjCImplementationDecl *ImpDecl = IFace->getImplementation()) 2098 Method = ImpDecl->getInstanceMethod(Sel); 2099 2100 if (!Method && IFace->getSuperClass()) 2101 return FindMethodInNestedImplementations(IFace->getSuperClass(), Sel); 2102 return Method; 2103} 2104 2105Action::OwningExprResult 2106Sema::ActOnMemberReferenceExpr(Scope *S, ExprArg Base, SourceLocation OpLoc, 2107 tok::TokenKind OpKind, SourceLocation MemberLoc, 2108 IdentifierInfo &Member, 2109 DeclPtrTy ObjCImpDecl, const CXXScopeSpec *SS) { 2110 // FIXME: handle the CXXScopeSpec for proper lookup of qualified-ids 2111 if (SS && SS->isInvalid()) 2112 return ExprError(); 2113 2114 Expr *BaseExpr = Base.takeAs<Expr>(); 2115 assert(BaseExpr && "no record expression"); 2116 2117 // Perform default conversions. 2118 DefaultFunctionArrayConversion(BaseExpr); 2119 2120 QualType BaseType = BaseExpr->getType(); 2121 assert(!BaseType.isNull() && "no type for member expression"); 2122 2123 // Get the type being accessed in BaseType. If this is an arrow, the BaseExpr 2124 // must have pointer type, and the accessed type is the pointee. 2125 if (OpKind == tok::arrow) { 2126 if (BaseType->isDependentType()) 2127 return Owned(new (Context) CXXUnresolvedMemberExpr(Context, 2128 BaseExpr, true, 2129 OpLoc, 2130 DeclarationName(&Member), 2131 MemberLoc)); 2132 else if (const PointerType *PT = BaseType->getAs<PointerType>()) 2133 BaseType = PT->getPointeeType(); 2134 else if (BaseType->isObjCObjectPointerType()) 2135 ; 2136 else 2137 return ExprError(Diag(MemberLoc, 2138 diag::err_typecheck_member_reference_arrow) 2139 << BaseType << BaseExpr->getSourceRange()); 2140 } else { 2141 if (BaseType->isDependentType()) { 2142 // Require that the base type isn't a pointer type 2143 // (so we'll report an error for) 2144 // T* t; 2145 // t.f; 2146 // 2147 // In Obj-C++, however, the above expression is valid, since it could be 2148 // accessing the 'f' property if T is an Obj-C interface. The extra check 2149 // allows this, while still reporting an error if T is a struct pointer. 2150 const PointerType *PT = BaseType->getAs<PointerType>(); 2151 2152 if (!PT || (getLangOptions().ObjC1 && 2153 !PT->getPointeeType()->isRecordType())) 2154 return Owned(new (Context) CXXUnresolvedMemberExpr(Context, 2155 BaseExpr, false, 2156 OpLoc, 2157 DeclarationName(&Member), 2158 MemberLoc)); 2159 } 2160 } 2161 2162 // Handle field access to simple records. This also handles access to fields 2163 // of the ObjC 'id' struct. 2164 if (const RecordType *RTy = BaseType->getAs<RecordType>()) { 2165 RecordDecl *RDecl = RTy->getDecl(); 2166 if (RequireCompleteType(OpLoc, BaseType, 2167 diag::err_typecheck_incomplete_tag, 2168 BaseExpr->getSourceRange())) 2169 return ExprError(); 2170 2171 DeclContext *DC = RDecl; 2172 if (SS && SS->isSet()) { 2173 // If the member name was a qualified-id, look into the 2174 // nested-name-specifier. 2175 DC = computeDeclContext(*SS, false); 2176 2177 // FIXME: If DC is not computable, we should build a 2178 // CXXUnresolvedMemberExpr. 2179 assert(DC && "Cannot handle non-computable dependent contexts in lookup"); 2180 } 2181 2182 // The record definition is complete, now make sure the member is valid. 2183 LookupResult Result 2184 = LookupQualifiedName(DC, DeclarationName(&Member), 2185 LookupMemberName, false); 2186 2187 if (SS && SS->isSet()) { 2188 QualType BaseTypeCanon 2189 = Context.getCanonicalType(BaseType).getUnqualifiedType(); 2190 QualType MemberTypeCanon 2191 = Context.getCanonicalType( 2192 Context.getTypeDeclType( 2193 dyn_cast<TypeDecl>(Result.getAsDecl()->getDeclContext()))); 2194 2195 if (BaseTypeCanon != MemberTypeCanon && 2196 !IsDerivedFrom(BaseTypeCanon, MemberTypeCanon)) 2197 return ExprError(Diag(SS->getBeginLoc(), 2198 diag::err_not_direct_base_or_virtual) 2199 << MemberTypeCanon << BaseTypeCanon); 2200 } 2201 2202 if (!Result) 2203 return ExprError(Diag(MemberLoc, diag::err_typecheck_no_member) 2204 << &Member << BaseExpr->getSourceRange()); 2205 if (Result.isAmbiguous()) { 2206 DiagnoseAmbiguousLookup(Result, DeclarationName(&Member), 2207 MemberLoc, BaseExpr->getSourceRange()); 2208 return ExprError(); 2209 } 2210 2211 NamedDecl *MemberDecl = Result; 2212 2213 // If the decl being referenced had an error, return an error for this 2214 // sub-expr without emitting another error, in order to avoid cascading 2215 // error cases. 2216 if (MemberDecl->isInvalidDecl()) 2217 return ExprError(); 2218 2219 // Check the use of this field 2220 if (DiagnoseUseOfDecl(MemberDecl, MemberLoc)) 2221 return ExprError(); 2222 2223 if (FieldDecl *FD = dyn_cast<FieldDecl>(MemberDecl)) { 2224 // We may have found a field within an anonymous union or struct 2225 // (C++ [class.union]). 2226 if (cast<RecordDecl>(FD->getDeclContext())->isAnonymousStructOrUnion()) 2227 return BuildAnonymousStructUnionMemberReference(MemberLoc, FD, 2228 BaseExpr, OpLoc); 2229 2230 // Figure out the type of the member; see C99 6.5.2.3p3, C++ [expr.ref] 2231 QualType MemberType = FD->getType(); 2232 if (const ReferenceType *Ref = MemberType->getAs<ReferenceType>()) 2233 MemberType = Ref->getPointeeType(); 2234 else { 2235 unsigned BaseAddrSpace = BaseType.getAddressSpace(); 2236 unsigned combinedQualifiers = 2237 MemberType.getCVRQualifiers() | BaseType.getCVRQualifiers(); 2238 if (FD->isMutable()) 2239 combinedQualifiers &= ~QualType::Const; 2240 MemberType = MemberType.getQualifiedType(combinedQualifiers); 2241 if (BaseAddrSpace != MemberType.getAddressSpace()) 2242 MemberType = Context.getAddrSpaceQualType(MemberType, BaseAddrSpace); 2243 } 2244 2245 MarkDeclarationReferenced(MemberLoc, FD); 2246 if (PerformObjectMemberConversion(BaseExpr, FD)) 2247 return ExprError(); 2248 return Owned(new (Context) MemberExpr(BaseExpr, OpKind == tok::arrow, FD, 2249 MemberLoc, MemberType)); 2250 } 2251 2252 if (VarDecl *Var = dyn_cast<VarDecl>(MemberDecl)) { 2253 MarkDeclarationReferenced(MemberLoc, MemberDecl); 2254 return Owned(new (Context) MemberExpr(BaseExpr, OpKind == tok::arrow, 2255 Var, MemberLoc, 2256 Var->getType().getNonReferenceType())); 2257 } 2258 if (FunctionDecl *MemberFn = dyn_cast<FunctionDecl>(MemberDecl)) { 2259 MarkDeclarationReferenced(MemberLoc, MemberDecl); 2260 return Owned(new (Context) MemberExpr(BaseExpr, OpKind == tok::arrow, 2261 MemberFn, MemberLoc, 2262 MemberFn->getType())); 2263 } 2264 if (OverloadedFunctionDecl *Ovl 2265 = dyn_cast<OverloadedFunctionDecl>(MemberDecl)) 2266 return Owned(new (Context) MemberExpr(BaseExpr, OpKind == tok::arrow, Ovl, 2267 MemberLoc, Context.OverloadTy)); 2268 if (EnumConstantDecl *Enum = dyn_cast<EnumConstantDecl>(MemberDecl)) { 2269 MarkDeclarationReferenced(MemberLoc, MemberDecl); 2270 return Owned(new (Context) MemberExpr(BaseExpr, OpKind == tok::arrow, 2271 Enum, MemberLoc, Enum->getType())); 2272 } 2273 if (isa<TypeDecl>(MemberDecl)) 2274 return ExprError(Diag(MemberLoc,diag::err_typecheck_member_reference_type) 2275 << DeclarationName(&Member) << int(OpKind == tok::arrow)); 2276 2277 // We found a declaration kind that we didn't expect. This is a 2278 // generic error message that tells the user that she can't refer 2279 // to this member with '.' or '->'. 2280 return ExprError(Diag(MemberLoc, 2281 diag::err_typecheck_member_reference_unknown) 2282 << DeclarationName(&Member) << int(OpKind == tok::arrow)); 2283 } 2284 2285 // Handle properties on ObjC 'Class' types. 2286 if (OpKind == tok::period && BaseType->isObjCClassType()) { 2287 // Also must look for a getter name which uses property syntax. 2288 Selector Sel = PP.getSelectorTable().getNullarySelector(&Member); 2289 if (ObjCMethodDecl *MD = getCurMethodDecl()) { 2290 ObjCInterfaceDecl *IFace = MD->getClassInterface(); 2291 ObjCMethodDecl *Getter; 2292 // FIXME: need to also look locally in the implementation. 2293 if ((Getter = IFace->lookupClassMethod(Sel))) { 2294 // Check the use of this method. 2295 if (DiagnoseUseOfDecl(Getter, MemberLoc)) 2296 return ExprError(); 2297 } 2298 // If we found a getter then this may be a valid dot-reference, we 2299 // will look for the matching setter, in case it is needed. 2300 Selector SetterSel = 2301 SelectorTable::constructSetterName(PP.getIdentifierTable(), 2302 PP.getSelectorTable(), &Member); 2303 ObjCMethodDecl *Setter = IFace->lookupClassMethod(SetterSel); 2304 if (!Setter) { 2305 // If this reference is in an @implementation, also check for 'private' 2306 // methods. 2307 Setter = FindMethodInNestedImplementations(IFace, SetterSel); 2308 } 2309 // Look through local category implementations associated with the class. 2310 if (!Setter) 2311 Setter = IFace->getCategoryClassMethod(SetterSel); 2312 2313 if (Setter && DiagnoseUseOfDecl(Setter, MemberLoc)) 2314 return ExprError(); 2315 2316 if (Getter || Setter) { 2317 QualType PType; 2318 2319 if (Getter) 2320 PType = Getter->getResultType(); 2321 else { 2322 for (ObjCMethodDecl::param_iterator PI = Setter->param_begin(), 2323 E = Setter->param_end(); PI != E; ++PI) 2324 PType = (*PI)->getType(); 2325 } 2326 // FIXME: we must check that the setter has property type. 2327 return Owned(new (Context) ObjCKVCRefExpr(Getter, PType, 2328 Setter, MemberLoc, BaseExpr)); 2329 } 2330 return ExprError(Diag(MemberLoc, diag::err_property_not_found) 2331 << &Member << BaseType); 2332 } 2333 } 2334 // Handle access to Objective-C instance variables, such as "Obj->ivar" and 2335 // (*Obj).ivar. 2336 if ((OpKind == tok::arrow && BaseType->isObjCObjectPointerType()) || 2337 (OpKind == tok::period && BaseType->isObjCInterfaceType())) { 2338 const ObjCObjectPointerType *OPT = BaseType->getAsObjCObjectPointerType(); 2339 const ObjCInterfaceType *IFaceT = 2340 OPT ? OPT->getInterfaceType() : BaseType->getAsObjCInterfaceType(); 2341 if (IFaceT) { 2342 ObjCInterfaceDecl *IDecl = IFaceT->getDecl(); 2343 ObjCInterfaceDecl *ClassDeclared; 2344 ObjCIvarDecl *IV = IDecl->lookupInstanceVariable(&Member, ClassDeclared); 2345 2346 if (IV) { 2347 // If the decl being referenced had an error, return an error for this 2348 // sub-expr without emitting another error, in order to avoid cascading 2349 // error cases. 2350 if (IV->isInvalidDecl()) 2351 return ExprError(); 2352 2353 // Check whether we can reference this field. 2354 if (DiagnoseUseOfDecl(IV, MemberLoc)) 2355 return ExprError(); 2356 if (IV->getAccessControl() != ObjCIvarDecl::Public && 2357 IV->getAccessControl() != ObjCIvarDecl::Package) { 2358 ObjCInterfaceDecl *ClassOfMethodDecl = 0; 2359 if (ObjCMethodDecl *MD = getCurMethodDecl()) 2360 ClassOfMethodDecl = MD->getClassInterface(); 2361 else if (ObjCImpDecl && getCurFunctionDecl()) { 2362 // Case of a c-function declared inside an objc implementation. 2363 // FIXME: For a c-style function nested inside an objc implementation 2364 // class, there is no implementation context available, so we pass 2365 // down the context as argument to this routine. Ideally, this context 2366 // need be passed down in the AST node and somehow calculated from the 2367 // AST for a function decl. 2368 Decl *ImplDecl = ObjCImpDecl.getAs<Decl>(); 2369 if (ObjCImplementationDecl *IMPD = 2370 dyn_cast<ObjCImplementationDecl>(ImplDecl)) 2371 ClassOfMethodDecl = IMPD->getClassInterface(); 2372 else if (ObjCCategoryImplDecl* CatImplClass = 2373 dyn_cast<ObjCCategoryImplDecl>(ImplDecl)) 2374 ClassOfMethodDecl = CatImplClass->getClassInterface(); 2375 } 2376 2377 if (IV->getAccessControl() == ObjCIvarDecl::Private) { 2378 if (ClassDeclared != IDecl || 2379 ClassOfMethodDecl != ClassDeclared) 2380 Diag(MemberLoc, diag::error_private_ivar_access) 2381 << IV->getDeclName(); 2382 } else if (!IDecl->isSuperClassOf(ClassOfMethodDecl)) 2383 // @protected 2384 Diag(MemberLoc, diag::error_protected_ivar_access) 2385 << IV->getDeclName(); 2386 } 2387 2388 return Owned(new (Context) ObjCIvarRefExpr(IV, IV->getType(), 2389 MemberLoc, BaseExpr, 2390 OpKind == tok::arrow)); 2391 } 2392 return ExprError(Diag(MemberLoc, diag::err_typecheck_member_reference_ivar) 2393 << IDecl->getDeclName() << &Member 2394 << BaseExpr->getSourceRange()); 2395 } 2396 // We have an 'id' type. Rather than fall through, we check if this 2397 // is a reference to 'isa'. 2398 if (Member.isStr("isa")) 2399 return Owned(new (Context) ObjCIsaExpr(BaseExpr, true, MemberLoc, 2400 Context.getObjCIdType())); 2401 } 2402 // Handle properties on 'id' and qualified "id". 2403 if (OpKind == tok::period && (BaseType->isObjCIdType() || 2404 BaseType->isObjCQualifiedIdType())) { 2405 const ObjCObjectPointerType *QIdTy = BaseType->getAsObjCObjectPointerType(); 2406 2407 // Check protocols on qualified interfaces. 2408 Selector Sel = PP.getSelectorTable().getNullarySelector(&Member); 2409 if (Decl *PMDecl = FindGetterNameDecl(QIdTy, Member, Sel, Context)) { 2410 if (ObjCPropertyDecl *PD = dyn_cast<ObjCPropertyDecl>(PMDecl)) { 2411 // Check the use of this declaration 2412 if (DiagnoseUseOfDecl(PD, MemberLoc)) 2413 return ExprError(); 2414 2415 return Owned(new (Context) ObjCPropertyRefExpr(PD, PD->getType(), 2416 MemberLoc, BaseExpr)); 2417 } 2418 if (ObjCMethodDecl *OMD = dyn_cast<ObjCMethodDecl>(PMDecl)) { 2419 // Check the use of this method. 2420 if (DiagnoseUseOfDecl(OMD, MemberLoc)) 2421 return ExprError(); 2422 2423 return Owned(new (Context) ObjCMessageExpr(BaseExpr, Sel, 2424 OMD->getResultType(), 2425 OMD, OpLoc, MemberLoc, 2426 NULL, 0)); 2427 } 2428 } 2429 2430 return ExprError(Diag(MemberLoc, diag::err_property_not_found) 2431 << &Member << BaseType); 2432 } 2433 // Handle Objective-C property access, which is "Obj.property" where Obj is a 2434 // pointer to a (potentially qualified) interface type. 2435 const ObjCObjectPointerType *OPT; 2436 if (OpKind == tok::period && 2437 (OPT = BaseType->getAsObjCInterfacePointerType())) { 2438 const ObjCInterfaceType *IFaceT = OPT->getInterfaceType(); 2439 ObjCInterfaceDecl *IFace = IFaceT->getDecl(); 2440 2441 // Search for a declared property first. 2442 if (ObjCPropertyDecl *PD = IFace->FindPropertyDeclaration(&Member)) { 2443 // Check whether we can reference this property. 2444 if (DiagnoseUseOfDecl(PD, MemberLoc)) 2445 return ExprError(); 2446 QualType ResTy = PD->getType(); 2447 Selector Sel = PP.getSelectorTable().getNullarySelector(&Member); 2448 ObjCMethodDecl *Getter = IFace->lookupInstanceMethod(Sel); 2449 if (DiagnosePropertyAccessorMismatch(PD, Getter, MemberLoc)) 2450 ResTy = Getter->getResultType(); 2451 return Owned(new (Context) ObjCPropertyRefExpr(PD, ResTy, 2452 MemberLoc, BaseExpr)); 2453 } 2454 // Check protocols on qualified interfaces. 2455 for (ObjCObjectPointerType::qual_iterator I = OPT->qual_begin(), 2456 E = OPT->qual_end(); I != E; ++I) 2457 if (ObjCPropertyDecl *PD = (*I)->FindPropertyDeclaration(&Member)) { 2458 // Check whether we can reference this property. 2459 if (DiagnoseUseOfDecl(PD, MemberLoc)) 2460 return ExprError(); 2461 2462 return Owned(new (Context) ObjCPropertyRefExpr(PD, PD->getType(), 2463 MemberLoc, BaseExpr)); 2464 } 2465 for (ObjCObjectPointerType::qual_iterator I = OPT->qual_begin(), 2466 E = OPT->qual_end(); I != E; ++I) 2467 if (ObjCPropertyDecl *PD = (*I)->FindPropertyDeclaration(&Member)) { 2468 // Check whether we can reference this property. 2469 if (DiagnoseUseOfDecl(PD, MemberLoc)) 2470 return ExprError(); 2471 2472 return Owned(new (Context) ObjCPropertyRefExpr(PD, PD->getType(), 2473 MemberLoc, BaseExpr)); 2474 } 2475 // If that failed, look for an "implicit" property by seeing if the nullary 2476 // selector is implemented. 2477 2478 // FIXME: The logic for looking up nullary and unary selectors should be 2479 // shared with the code in ActOnInstanceMessage. 2480 2481 Selector Sel = PP.getSelectorTable().getNullarySelector(&Member); 2482 ObjCMethodDecl *Getter = IFace->lookupInstanceMethod(Sel); 2483 2484 // If this reference is in an @implementation, check for 'private' methods. 2485 if (!Getter) 2486 Getter = FindMethodInNestedImplementations(IFace, Sel); 2487 2488 // Look through local category implementations associated with the class. 2489 if (!Getter) 2490 Getter = IFace->getCategoryInstanceMethod(Sel); 2491 if (Getter) { 2492 // Check if we can reference this property. 2493 if (DiagnoseUseOfDecl(Getter, MemberLoc)) 2494 return ExprError(); 2495 } 2496 // If we found a getter then this may be a valid dot-reference, we 2497 // will look for the matching setter, in case it is needed. 2498 Selector SetterSel = 2499 SelectorTable::constructSetterName(PP.getIdentifierTable(), 2500 PP.getSelectorTable(), &Member); 2501 ObjCMethodDecl *Setter = IFace->lookupInstanceMethod(SetterSel); 2502 if (!Setter) { 2503 // If this reference is in an @implementation, also check for 'private' 2504 // methods. 2505 Setter = FindMethodInNestedImplementations(IFace, SetterSel); 2506 } 2507 // Look through local category implementations associated with the class. 2508 if (!Setter) 2509 Setter = IFace->getCategoryInstanceMethod(SetterSel); 2510 2511 if (Setter && DiagnoseUseOfDecl(Setter, MemberLoc)) 2512 return ExprError(); 2513 2514 if (Getter || Setter) { 2515 QualType PType; 2516 2517 if (Getter) 2518 PType = Getter->getResultType(); 2519 else { 2520 for (ObjCMethodDecl::param_iterator PI = Setter->param_begin(), 2521 E = Setter->param_end(); PI != E; ++PI) 2522 PType = (*PI)->getType(); 2523 } 2524 // FIXME: we must check that the setter has property type. 2525 return Owned(new (Context) ObjCKVCRefExpr(Getter, PType, 2526 Setter, MemberLoc, BaseExpr)); 2527 } 2528 return ExprError(Diag(MemberLoc, diag::err_property_not_found) 2529 << &Member << BaseType); 2530 } 2531 2532 // Handle the following exceptional case (*Obj).isa. 2533 if (OpKind == tok::period && 2534 BaseType->isSpecificBuiltinType(BuiltinType::ObjCId) && 2535 Member.isStr("isa")) 2536 return Owned(new (Context) ObjCIsaExpr(BaseExpr, false, MemberLoc, 2537 Context.getObjCIdType())); 2538 2539 // Handle 'field access' to vectors, such as 'V.xx'. 2540 if (BaseType->isExtVectorType()) { 2541 QualType ret = CheckExtVectorComponent(BaseType, OpLoc, Member, MemberLoc); 2542 if (ret.isNull()) 2543 return ExprError(); 2544 return Owned(new (Context) ExtVectorElementExpr(ret, BaseExpr, Member, 2545 MemberLoc)); 2546 } 2547 2548 Diag(MemberLoc, diag::err_typecheck_member_reference_struct_union) 2549 << BaseType << BaseExpr->getSourceRange(); 2550 2551 // If the user is trying to apply -> or . to a function or function 2552 // pointer, it's probably because they forgot parentheses to call 2553 // the function. Suggest the addition of those parentheses. 2554 if (BaseType == Context.OverloadTy || 2555 BaseType->isFunctionType() || 2556 (BaseType->isPointerType() && 2557 BaseType->getAs<PointerType>()->isFunctionType())) { 2558 SourceLocation Loc = PP.getLocForEndOfToken(BaseExpr->getLocEnd()); 2559 Diag(Loc, diag::note_member_reference_needs_call) 2560 << CodeModificationHint::CreateInsertion(Loc, "()"); 2561 } 2562 2563 return ExprError(); 2564} 2565 2566/// ConvertArgumentsForCall - Converts the arguments specified in 2567/// Args/NumArgs to the parameter types of the function FDecl with 2568/// function prototype Proto. Call is the call expression itself, and 2569/// Fn is the function expression. For a C++ member function, this 2570/// routine does not attempt to convert the object argument. Returns 2571/// true if the call is ill-formed. 2572bool 2573Sema::ConvertArgumentsForCall(CallExpr *Call, Expr *Fn, 2574 FunctionDecl *FDecl, 2575 const FunctionProtoType *Proto, 2576 Expr **Args, unsigned NumArgs, 2577 SourceLocation RParenLoc) { 2578 // C99 6.5.2.2p7 - the arguments are implicitly converted, as if by 2579 // assignment, to the types of the corresponding parameter, ... 2580 unsigned NumArgsInProto = Proto->getNumArgs(); 2581 unsigned NumArgsToCheck = NumArgs; 2582 bool Invalid = false; 2583 2584 // If too few arguments are available (and we don't have default 2585 // arguments for the remaining parameters), don't make the call. 2586 if (NumArgs < NumArgsInProto) { 2587 if (!FDecl || NumArgs < FDecl->getMinRequiredArguments()) 2588 return Diag(RParenLoc, diag::err_typecheck_call_too_few_args) 2589 << Fn->getType()->isBlockPointerType() << Fn->getSourceRange(); 2590 // Use default arguments for missing arguments 2591 NumArgsToCheck = NumArgsInProto; 2592 Call->setNumArgs(Context, NumArgsInProto); 2593 } 2594 2595 // If too many are passed and not variadic, error on the extras and drop 2596 // them. 2597 if (NumArgs > NumArgsInProto) { 2598 if (!Proto->isVariadic()) { 2599 Diag(Args[NumArgsInProto]->getLocStart(), 2600 diag::err_typecheck_call_too_many_args) 2601 << Fn->getType()->isBlockPointerType() << Fn->getSourceRange() 2602 << SourceRange(Args[NumArgsInProto]->getLocStart(), 2603 Args[NumArgs-1]->getLocEnd()); 2604 // This deletes the extra arguments. 2605 Call->setNumArgs(Context, NumArgsInProto); 2606 Invalid = true; 2607 } 2608 NumArgsToCheck = NumArgsInProto; 2609 } 2610 2611 // Continue to check argument types (even if we have too few/many args). 2612 for (unsigned i = 0; i != NumArgsToCheck; i++) { 2613 QualType ProtoArgType = Proto->getArgType(i); 2614 2615 Expr *Arg; 2616 if (i < NumArgs) { 2617 Arg = Args[i]; 2618 2619 if (RequireCompleteType(Arg->getSourceRange().getBegin(), 2620 ProtoArgType, 2621 diag::err_call_incomplete_argument, 2622 Arg->getSourceRange())) 2623 return true; 2624 2625 // Pass the argument. 2626 if (PerformCopyInitialization(Arg, ProtoArgType, "passing")) 2627 return true; 2628 } else { 2629 if (FDecl->getParamDecl(i)->hasUnparsedDefaultArg()) { 2630 Diag (Call->getSourceRange().getBegin(), 2631 diag::err_use_of_default_argument_to_function_declared_later) << 2632 FDecl << cast<CXXRecordDecl>(FDecl->getDeclContext())->getDeclName(); 2633 Diag(UnparsedDefaultArgLocs[FDecl->getParamDecl(i)], 2634 diag::note_default_argument_declared_here); 2635 } else { 2636 Expr *DefaultExpr = FDecl->getParamDecl(i)->getDefaultArg(); 2637 2638 // If the default expression creates temporaries, we need to 2639 // push them to the current stack of expression temporaries so they'll 2640 // be properly destroyed. 2641 if (CXXExprWithTemporaries *E 2642 = dyn_cast_or_null<CXXExprWithTemporaries>(DefaultExpr)) { 2643 assert(!E->shouldDestroyTemporaries() && 2644 "Can't destroy temporaries in a default argument expr!"); 2645 for (unsigned I = 0, N = E->getNumTemporaries(); I != N; ++I) 2646 ExprTemporaries.push_back(E->getTemporary(I)); 2647 } 2648 } 2649 2650 // We already type-checked the argument, so we know it works. 2651 Arg = new (Context) CXXDefaultArgExpr(FDecl->getParamDecl(i)); 2652 } 2653 2654 QualType ArgType = Arg->getType(); 2655 2656 Call->setArg(i, Arg); 2657 } 2658 2659 // If this is a variadic call, handle args passed through "...". 2660 if (Proto->isVariadic()) { 2661 VariadicCallType CallType = VariadicFunction; 2662 if (Fn->getType()->isBlockPointerType()) 2663 CallType = VariadicBlock; // Block 2664 else if (isa<MemberExpr>(Fn)) 2665 CallType = VariadicMethod; 2666 2667 // Promote the arguments (C99 6.5.2.2p7). 2668 for (unsigned i = NumArgsInProto; i != NumArgs; i++) { 2669 Expr *Arg = Args[i]; 2670 Invalid |= DefaultVariadicArgumentPromotion(Arg, CallType); 2671 Call->setArg(i, Arg); 2672 } 2673 } 2674 2675 return Invalid; 2676} 2677 2678/// ActOnCallExpr - Handle a call to Fn with the specified array of arguments. 2679/// This provides the location of the left/right parens and a list of comma 2680/// locations. 2681Action::OwningExprResult 2682Sema::ActOnCallExpr(Scope *S, ExprArg fn, SourceLocation LParenLoc, 2683 MultiExprArg args, 2684 SourceLocation *CommaLocs, SourceLocation RParenLoc) { 2685 unsigned NumArgs = args.size(); 2686 Expr *Fn = fn.takeAs<Expr>(); 2687 Expr **Args = reinterpret_cast<Expr**>(args.release()); 2688 assert(Fn && "no function call expression"); 2689 FunctionDecl *FDecl = NULL; 2690 NamedDecl *NDecl = NULL; 2691 DeclarationName UnqualifiedName; 2692 2693 if (getLangOptions().CPlusPlus) { 2694 // Determine whether this is a dependent call inside a C++ template, 2695 // in which case we won't do any semantic analysis now. 2696 // FIXME: Will need to cache the results of name lookup (including ADL) in 2697 // Fn. 2698 bool Dependent = false; 2699 if (Fn->isTypeDependent()) 2700 Dependent = true; 2701 else if (Expr::hasAnyTypeDependentArguments(Args, NumArgs)) 2702 Dependent = true; 2703 2704 if (Dependent) 2705 return Owned(new (Context) CallExpr(Context, Fn, Args, NumArgs, 2706 Context.DependentTy, RParenLoc)); 2707 2708 // Determine whether this is a call to an object (C++ [over.call.object]). 2709 if (Fn->getType()->isRecordType()) 2710 return Owned(BuildCallToObjectOfClassType(S, Fn, LParenLoc, Args, NumArgs, 2711 CommaLocs, RParenLoc)); 2712 2713 // Determine whether this is a call to a member function. 2714 if (MemberExpr *MemExpr = dyn_cast<MemberExpr>(Fn->IgnoreParens())) { 2715 NamedDecl *MemDecl = MemExpr->getMemberDecl(); 2716 if (isa<OverloadedFunctionDecl>(MemDecl) || 2717 isa<CXXMethodDecl>(MemDecl) || 2718 (isa<FunctionTemplateDecl>(MemDecl) && 2719 isa<CXXMethodDecl>( 2720 cast<FunctionTemplateDecl>(MemDecl)->getTemplatedDecl()))) 2721 return Owned(BuildCallToMemberFunction(S, Fn, LParenLoc, Args, NumArgs, 2722 CommaLocs, RParenLoc)); 2723 } 2724 } 2725 2726 // If we're directly calling a function, get the appropriate declaration. 2727 // Also, in C++, keep track of whether we should perform argument-dependent 2728 // lookup and whether there were any explicitly-specified template arguments. 2729 Expr *FnExpr = Fn; 2730 bool ADL = true; 2731 bool HasExplicitTemplateArgs = 0; 2732 const TemplateArgument *ExplicitTemplateArgs = 0; 2733 unsigned NumExplicitTemplateArgs = 0; 2734 while (true) { 2735 if (ImplicitCastExpr *IcExpr = dyn_cast<ImplicitCastExpr>(FnExpr)) 2736 FnExpr = IcExpr->getSubExpr(); 2737 else if (ParenExpr *PExpr = dyn_cast<ParenExpr>(FnExpr)) { 2738 // Parentheses around a function disable ADL 2739 // (C++0x [basic.lookup.argdep]p1). 2740 ADL = false; 2741 FnExpr = PExpr->getSubExpr(); 2742 } else if (isa<UnaryOperator>(FnExpr) && 2743 cast<UnaryOperator>(FnExpr)->getOpcode() 2744 == UnaryOperator::AddrOf) { 2745 FnExpr = cast<UnaryOperator>(FnExpr)->getSubExpr(); 2746 } else if (DeclRefExpr *DRExpr = dyn_cast<DeclRefExpr>(FnExpr)) { 2747 // Qualified names disable ADL (C++0x [basic.lookup.argdep]p1). 2748 ADL &= !isa<QualifiedDeclRefExpr>(DRExpr); 2749 NDecl = dyn_cast<NamedDecl>(DRExpr->getDecl()); 2750 break; 2751 } else if (UnresolvedFunctionNameExpr *DepName 2752 = dyn_cast<UnresolvedFunctionNameExpr>(FnExpr)) { 2753 UnqualifiedName = DepName->getName(); 2754 break; 2755 } else if (TemplateIdRefExpr *TemplateIdRef 2756 = dyn_cast<TemplateIdRefExpr>(FnExpr)) { 2757 NDecl = TemplateIdRef->getTemplateName().getAsTemplateDecl(); 2758 if (!NDecl) 2759 NDecl = TemplateIdRef->getTemplateName().getAsOverloadedFunctionDecl(); 2760 HasExplicitTemplateArgs = true; 2761 ExplicitTemplateArgs = TemplateIdRef->getTemplateArgs(); 2762 NumExplicitTemplateArgs = TemplateIdRef->getNumTemplateArgs(); 2763 2764 // C++ [temp.arg.explicit]p6: 2765 // [Note: For simple function names, argument dependent lookup (3.4.2) 2766 // applies even when the function name is not visible within the 2767 // scope of the call. This is because the call still has the syntactic 2768 // form of a function call (3.4.1). But when a function template with 2769 // explicit template arguments is used, the call does not have the 2770 // correct syntactic form unless there is a function template with 2771 // that name visible at the point of the call. If no such name is 2772 // visible, the call is not syntactically well-formed and 2773 // argument-dependent lookup does not apply. If some such name is 2774 // visible, argument dependent lookup applies and additional function 2775 // templates may be found in other namespaces. 2776 // 2777 // The summary of this paragraph is that, if we get to this point and the 2778 // template-id was not a qualified name, then argument-dependent lookup 2779 // is still possible. 2780 if (TemplateIdRef->getQualifier()) 2781 ADL = false; 2782 break; 2783 } else { 2784 // Any kind of name that does not refer to a declaration (or 2785 // set of declarations) disables ADL (C++0x [basic.lookup.argdep]p3). 2786 ADL = false; 2787 break; 2788 } 2789 } 2790 2791 OverloadedFunctionDecl *Ovl = 0; 2792 FunctionTemplateDecl *FunctionTemplate = 0; 2793 if (NDecl) { 2794 FDecl = dyn_cast<FunctionDecl>(NDecl); 2795 if ((FunctionTemplate = dyn_cast<FunctionTemplateDecl>(NDecl))) 2796 FDecl = FunctionTemplate->getTemplatedDecl(); 2797 else 2798 FDecl = dyn_cast<FunctionDecl>(NDecl); 2799 Ovl = dyn_cast<OverloadedFunctionDecl>(NDecl); 2800 } 2801 2802 if (Ovl || FunctionTemplate || 2803 (getLangOptions().CPlusPlus && (FDecl || UnqualifiedName))) { 2804 // We don't perform ADL for implicit declarations of builtins. 2805 if (FDecl && FDecl->getBuiltinID(Context) && FDecl->isImplicit()) 2806 ADL = false; 2807 2808 // We don't perform ADL in C. 2809 if (!getLangOptions().CPlusPlus) 2810 ADL = false; 2811 2812 if (Ovl || FunctionTemplate || ADL) { 2813 FDecl = ResolveOverloadedCallFn(Fn, NDecl, UnqualifiedName, 2814 HasExplicitTemplateArgs, 2815 ExplicitTemplateArgs, 2816 NumExplicitTemplateArgs, 2817 LParenLoc, Args, NumArgs, CommaLocs, 2818 RParenLoc, ADL); 2819 if (!FDecl) 2820 return ExprError(); 2821 2822 // Update Fn to refer to the actual function selected. 2823 Expr *NewFn = 0; 2824 if (QualifiedDeclRefExpr *QDRExpr 2825 = dyn_cast<QualifiedDeclRefExpr>(FnExpr)) 2826 NewFn = new (Context) QualifiedDeclRefExpr(FDecl, FDecl->getType(), 2827 QDRExpr->getLocation(), 2828 false, false, 2829 QDRExpr->getQualifierRange(), 2830 QDRExpr->getQualifier()); 2831 else 2832 NewFn = new (Context) DeclRefExpr(FDecl, FDecl->getType(), 2833 Fn->getSourceRange().getBegin()); 2834 Fn->Destroy(Context); 2835 Fn = NewFn; 2836 } 2837 } 2838 2839 // Promote the function operand. 2840 UsualUnaryConversions(Fn); 2841 2842 // Make the call expr early, before semantic checks. This guarantees cleanup 2843 // of arguments and function on error. 2844 ExprOwningPtr<CallExpr> TheCall(this, new (Context) CallExpr(Context, Fn, 2845 Args, NumArgs, 2846 Context.BoolTy, 2847 RParenLoc)); 2848 2849 const FunctionType *FuncT; 2850 if (!Fn->getType()->isBlockPointerType()) { 2851 // C99 6.5.2.2p1 - "The expression that denotes the called function shall 2852 // have type pointer to function". 2853 const PointerType *PT = Fn->getType()->getAs<PointerType>(); 2854 if (PT == 0) 2855 return ExprError(Diag(LParenLoc, diag::err_typecheck_call_not_function) 2856 << Fn->getType() << Fn->getSourceRange()); 2857 FuncT = PT->getPointeeType()->getAsFunctionType(); 2858 } else { // This is a block call. 2859 FuncT = Fn->getType()->getAs<BlockPointerType>()->getPointeeType()-> 2860 getAsFunctionType(); 2861 } 2862 if (FuncT == 0) 2863 return ExprError(Diag(LParenLoc, diag::err_typecheck_call_not_function) 2864 << Fn->getType() << Fn->getSourceRange()); 2865 2866 // Check for a valid return type 2867 if (!FuncT->getResultType()->isVoidType() && 2868 RequireCompleteType(Fn->getSourceRange().getBegin(), 2869 FuncT->getResultType(), 2870 diag::err_call_incomplete_return, 2871 TheCall->getSourceRange())) 2872 return ExprError(); 2873 2874 // We know the result type of the call, set it. 2875 TheCall->setType(FuncT->getResultType().getNonReferenceType()); 2876 2877 if (const FunctionProtoType *Proto = dyn_cast<FunctionProtoType>(FuncT)) { 2878 if (ConvertArgumentsForCall(&*TheCall, Fn, FDecl, Proto, Args, NumArgs, 2879 RParenLoc)) 2880 return ExprError(); 2881 } else { 2882 assert(isa<FunctionNoProtoType>(FuncT) && "Unknown FunctionType!"); 2883 2884 if (FDecl) { 2885 // Check if we have too few/too many template arguments, based 2886 // on our knowledge of the function definition. 2887 const FunctionDecl *Def = 0; 2888 if (FDecl->getBody(Def) && NumArgs != Def->param_size()) { 2889 const FunctionProtoType *Proto = 2890 Def->getType()->getAsFunctionProtoType(); 2891 if (!Proto || !(Proto->isVariadic() && NumArgs >= Def->param_size())) { 2892 Diag(RParenLoc, diag::warn_call_wrong_number_of_arguments) 2893 << (NumArgs > Def->param_size()) << FDecl << Fn->getSourceRange(); 2894 } 2895 } 2896 } 2897 2898 // Promote the arguments (C99 6.5.2.2p6). 2899 for (unsigned i = 0; i != NumArgs; i++) { 2900 Expr *Arg = Args[i]; 2901 DefaultArgumentPromotion(Arg); 2902 if (RequireCompleteType(Arg->getSourceRange().getBegin(), 2903 Arg->getType(), 2904 diag::err_call_incomplete_argument, 2905 Arg->getSourceRange())) 2906 return ExprError(); 2907 TheCall->setArg(i, Arg); 2908 } 2909 } 2910 2911 if (CXXMethodDecl *Method = dyn_cast_or_null<CXXMethodDecl>(FDecl)) 2912 if (!Method->isStatic()) 2913 return ExprError(Diag(LParenLoc, diag::err_member_call_without_object) 2914 << Fn->getSourceRange()); 2915 2916 // Check for sentinels 2917 if (NDecl) 2918 DiagnoseSentinelCalls(NDecl, LParenLoc, Args, NumArgs); 2919 // Do special checking on direct calls to functions. 2920 if (FDecl) 2921 return CheckFunctionCall(FDecl, TheCall.take()); 2922 if (NDecl) 2923 return CheckBlockCall(NDecl, TheCall.take()); 2924 2925 return Owned(TheCall.take()); 2926} 2927 2928Action::OwningExprResult 2929Sema::ActOnCompoundLiteral(SourceLocation LParenLoc, TypeTy *Ty, 2930 SourceLocation RParenLoc, ExprArg InitExpr) { 2931 assert((Ty != 0) && "ActOnCompoundLiteral(): missing type"); 2932 QualType literalType = QualType::getFromOpaquePtr(Ty); 2933 // FIXME: put back this assert when initializers are worked out. 2934 //assert((InitExpr != 0) && "ActOnCompoundLiteral(): missing expression"); 2935 Expr *literalExpr = static_cast<Expr*>(InitExpr.get()); 2936 2937 if (literalType->isArrayType()) { 2938 if (literalType->isVariableArrayType()) 2939 return ExprError(Diag(LParenLoc, diag::err_variable_object_no_init) 2940 << SourceRange(LParenLoc, literalExpr->getSourceRange().getEnd())); 2941 } else if (!literalType->isDependentType() && 2942 RequireCompleteType(LParenLoc, literalType, 2943 diag::err_typecheck_decl_incomplete_type, 2944 SourceRange(LParenLoc, literalExpr->getSourceRange().getEnd()))) 2945 return ExprError(); 2946 2947 if (CheckInitializerTypes(literalExpr, literalType, LParenLoc, 2948 DeclarationName(), /*FIXME:DirectInit=*/false)) 2949 return ExprError(); 2950 2951 bool isFileScope = getCurFunctionOrMethodDecl() == 0; 2952 if (isFileScope) { // 6.5.2.5p3 2953 if (CheckForConstantInitializer(literalExpr, literalType)) 2954 return ExprError(); 2955 } 2956 InitExpr.release(); 2957 return Owned(new (Context) CompoundLiteralExpr(LParenLoc, literalType, 2958 literalExpr, isFileScope)); 2959} 2960 2961Action::OwningExprResult 2962Sema::ActOnInitList(SourceLocation LBraceLoc, MultiExprArg initlist, 2963 SourceLocation RBraceLoc) { 2964 unsigned NumInit = initlist.size(); 2965 Expr **InitList = reinterpret_cast<Expr**>(initlist.release()); 2966 2967 // Semantic analysis for initializers is done by ActOnDeclarator() and 2968 // CheckInitializer() - it requires knowledge of the object being intialized. 2969 2970 InitListExpr *E = new (Context) InitListExpr(LBraceLoc, InitList, NumInit, 2971 RBraceLoc); 2972 E->setType(Context.VoidTy); // FIXME: just a place holder for now. 2973 return Owned(E); 2974} 2975 2976/// CheckCastTypes - Check type constraints for casting between types. 2977bool Sema::CheckCastTypes(SourceRange TyR, QualType castType, Expr *&castExpr, 2978 CastExpr::CastKind& Kind, bool FunctionalStyle) { 2979 if (getLangOptions().CPlusPlus) 2980 return CXXCheckCStyleCast(TyR, castType, castExpr, Kind, FunctionalStyle); 2981 2982 UsualUnaryConversions(castExpr); 2983 2984 // C99 6.5.4p2: the cast type needs to be void or scalar and the expression 2985 // type needs to be scalar. 2986 if (castType->isVoidType()) { 2987 // Cast to void allows any expr type. 2988 } else if (!castType->isScalarType() && !castType->isVectorType()) { 2989 if (Context.getCanonicalType(castType).getUnqualifiedType() == 2990 Context.getCanonicalType(castExpr->getType().getUnqualifiedType()) && 2991 (castType->isStructureType() || castType->isUnionType())) { 2992 // GCC struct/union extension: allow cast to self. 2993 // FIXME: Check that the cast destination type is complete. 2994 Diag(TyR.getBegin(), diag::ext_typecheck_cast_nonscalar) 2995 << castType << castExpr->getSourceRange(); 2996 Kind = CastExpr::CK_NoOp; 2997 } else if (castType->isUnionType()) { 2998 // GCC cast to union extension 2999 RecordDecl *RD = castType->getAs<RecordType>()->getDecl(); 3000 RecordDecl::field_iterator Field, FieldEnd; 3001 for (Field = RD->field_begin(), FieldEnd = RD->field_end(); 3002 Field != FieldEnd; ++Field) { 3003 if (Context.getCanonicalType(Field->getType()).getUnqualifiedType() == 3004 Context.getCanonicalType(castExpr->getType()).getUnqualifiedType()) { 3005 Diag(TyR.getBegin(), diag::ext_typecheck_cast_to_union) 3006 << castExpr->getSourceRange(); 3007 break; 3008 } 3009 } 3010 if (Field == FieldEnd) 3011 return Diag(TyR.getBegin(), diag::err_typecheck_cast_to_union_no_type) 3012 << castExpr->getType() << castExpr->getSourceRange(); 3013 Kind = CastExpr::CK_ToUnion; 3014 } else { 3015 // Reject any other conversions to non-scalar types. 3016 return Diag(TyR.getBegin(), diag::err_typecheck_cond_expect_scalar) 3017 << castType << castExpr->getSourceRange(); 3018 } 3019 } else if (!castExpr->getType()->isScalarType() && 3020 !castExpr->getType()->isVectorType()) { 3021 return Diag(castExpr->getLocStart(), 3022 diag::err_typecheck_expect_scalar_operand) 3023 << castExpr->getType() << castExpr->getSourceRange(); 3024 } else if (castType->isExtVectorType()) { 3025 if (CheckExtVectorCast(TyR, castType, castExpr->getType())) 3026 return true; 3027 } else if (castType->isVectorType()) { 3028 if (CheckVectorCast(TyR, castType, castExpr->getType())) 3029 return true; 3030 } else if (castExpr->getType()->isVectorType()) { 3031 if (CheckVectorCast(TyR, castExpr->getType(), castType)) 3032 return true; 3033 } else if (getLangOptions().ObjC1 && isa<ObjCSuperExpr>(castExpr)) { 3034 return Diag(castExpr->getLocStart(), diag::err_illegal_super_cast) << TyR; 3035 } else if (!castType->isArithmeticType()) { 3036 QualType castExprType = castExpr->getType(); 3037 if (!castExprType->isIntegralType() && castExprType->isArithmeticType()) 3038 return Diag(castExpr->getLocStart(), 3039 diag::err_cast_pointer_from_non_pointer_int) 3040 << castExprType << castExpr->getSourceRange(); 3041 } else if (!castExpr->getType()->isArithmeticType()) { 3042 if (!castType->isIntegralType() && castType->isArithmeticType()) 3043 return Diag(castExpr->getLocStart(), 3044 diag::err_cast_pointer_to_non_pointer_int) 3045 << castType << castExpr->getSourceRange(); 3046 } 3047 if (isa<ObjCSelectorExpr>(castExpr)) 3048 return Diag(castExpr->getLocStart(), diag::err_cast_selector_expr); 3049 return false; 3050} 3051 3052bool Sema::CheckVectorCast(SourceRange R, QualType VectorTy, QualType Ty) { 3053 assert(VectorTy->isVectorType() && "Not a vector type!"); 3054 3055 if (Ty->isVectorType() || Ty->isIntegerType()) { 3056 if (Context.getTypeSize(VectorTy) != Context.getTypeSize(Ty)) 3057 return Diag(R.getBegin(), 3058 Ty->isVectorType() ? 3059 diag::err_invalid_conversion_between_vectors : 3060 diag::err_invalid_conversion_between_vector_and_integer) 3061 << VectorTy << Ty << R; 3062 } else 3063 return Diag(R.getBegin(), 3064 diag::err_invalid_conversion_between_vector_and_scalar) 3065 << VectorTy << Ty << R; 3066 3067 return false; 3068} 3069 3070bool Sema::CheckExtVectorCast(SourceRange R, QualType DestTy, QualType SrcTy) { 3071 assert(DestTy->isExtVectorType() && "Not an extended vector type!"); 3072 3073 // If SrcTy is a VectorType, the total size must match to explicitly cast to 3074 // an ExtVectorType. 3075 if (SrcTy->isVectorType()) { 3076 if (Context.getTypeSize(DestTy) != Context.getTypeSize(SrcTy)) 3077 return Diag(R.getBegin(),diag::err_invalid_conversion_between_ext_vectors) 3078 << DestTy << SrcTy << R; 3079 return false; 3080 } 3081 3082 // All non-pointer scalars can be cast to ExtVector type. The appropriate 3083 // conversion will take place first from scalar to elt type, and then 3084 // splat from elt type to vector. 3085 if (SrcTy->isPointerType()) 3086 return Diag(R.getBegin(), 3087 diag::err_invalid_conversion_between_vector_and_scalar) 3088 << DestTy << SrcTy << R; 3089 return false; 3090} 3091 3092Action::OwningExprResult 3093Sema::ActOnCastExpr(SourceLocation LParenLoc, TypeTy *Ty, 3094 SourceLocation RParenLoc, ExprArg Op) { 3095 CastExpr::CastKind Kind = CastExpr::CK_Unknown; 3096 3097 assert((Ty != 0) && (Op.get() != 0) && 3098 "ActOnCastExpr(): missing type or expr"); 3099 3100 Expr *castExpr = Op.takeAs<Expr>(); 3101 QualType castType = QualType::getFromOpaquePtr(Ty); 3102 3103 if (CheckCastTypes(SourceRange(LParenLoc, RParenLoc), castType, castExpr, 3104 Kind)) 3105 return ExprError(); 3106 return Owned(new (Context) CStyleCastExpr(castType.getNonReferenceType(), 3107 Kind, castExpr, castType, 3108 LParenLoc, RParenLoc)); 3109} 3110 3111/// Note that lhs is not null here, even if this is the gnu "x ?: y" extension. 3112/// In that case, lhs = cond. 3113/// C99 6.5.15 3114QualType Sema::CheckConditionalOperands(Expr *&Cond, Expr *&LHS, Expr *&RHS, 3115 SourceLocation QuestionLoc) { 3116 // C++ is sufficiently different to merit its own checker. 3117 if (getLangOptions().CPlusPlus) 3118 return CXXCheckConditionalOperands(Cond, LHS, RHS, QuestionLoc); 3119 3120 UsualUnaryConversions(Cond); 3121 UsualUnaryConversions(LHS); 3122 UsualUnaryConversions(RHS); 3123 QualType CondTy = Cond->getType(); 3124 QualType LHSTy = LHS->getType(); 3125 QualType RHSTy = RHS->getType(); 3126 3127 // first, check the condition. 3128 if (!CondTy->isScalarType()) { // C99 6.5.15p2 3129 Diag(Cond->getLocStart(), diag::err_typecheck_cond_expect_scalar) 3130 << CondTy; 3131 return QualType(); 3132 } 3133 3134 // Now check the two expressions. 3135 3136 // If both operands have arithmetic type, do the usual arithmetic conversions 3137 // to find a common type: C99 6.5.15p3,5. 3138 if (LHSTy->isArithmeticType() && RHSTy->isArithmeticType()) { 3139 UsualArithmeticConversions(LHS, RHS); 3140 return LHS->getType(); 3141 } 3142 3143 // If both operands are the same structure or union type, the result is that 3144 // type. 3145 if (const RecordType *LHSRT = LHSTy->getAs<RecordType>()) { // C99 6.5.15p3 3146 if (const RecordType *RHSRT = RHSTy->getAs<RecordType>()) 3147 if (LHSRT->getDecl() == RHSRT->getDecl()) 3148 // "If both the operands have structure or union type, the result has 3149 // that type." This implies that CV qualifiers are dropped. 3150 return LHSTy.getUnqualifiedType(); 3151 // FIXME: Type of conditional expression must be complete in C mode. 3152 } 3153 3154 // C99 6.5.15p5: "If both operands have void type, the result has void type." 3155 // The following || allows only one side to be void (a GCC-ism). 3156 if (LHSTy->isVoidType() || RHSTy->isVoidType()) { 3157 if (!LHSTy->isVoidType()) 3158 Diag(RHS->getLocStart(), diag::ext_typecheck_cond_one_void) 3159 << RHS->getSourceRange(); 3160 if (!RHSTy->isVoidType()) 3161 Diag(LHS->getLocStart(), diag::ext_typecheck_cond_one_void) 3162 << LHS->getSourceRange(); 3163 ImpCastExprToType(LHS, Context.VoidTy); 3164 ImpCastExprToType(RHS, Context.VoidTy); 3165 return Context.VoidTy; 3166 } 3167 // C99 6.5.15p6 - "if one operand is a null pointer constant, the result has 3168 // the type of the other operand." 3169 if ((LHSTy->isAnyPointerType() || LHSTy->isBlockPointerType()) && 3170 RHS->isNullPointerConstant(Context)) { 3171 ImpCastExprToType(RHS, LHSTy); // promote the null to a pointer. 3172 return LHSTy; 3173 } 3174 if ((RHSTy->isAnyPointerType() || RHSTy->isBlockPointerType()) && 3175 LHS->isNullPointerConstant(Context)) { 3176 ImpCastExprToType(LHS, RHSTy); // promote the null to a pointer. 3177 return RHSTy; 3178 } 3179 // Handle block pointer types. 3180 if (LHSTy->isBlockPointerType() || RHSTy->isBlockPointerType()) { 3181 if (!LHSTy->isBlockPointerType() || !RHSTy->isBlockPointerType()) { 3182 if (LHSTy->isVoidPointerType() || RHSTy->isVoidPointerType()) { 3183 QualType destType = Context.getPointerType(Context.VoidTy); 3184 ImpCastExprToType(LHS, destType); 3185 ImpCastExprToType(RHS, destType); 3186 return destType; 3187 } 3188 Diag(QuestionLoc, diag::err_typecheck_cond_incompatible_operands) 3189 << LHSTy << RHSTy << LHS->getSourceRange() << RHS->getSourceRange(); 3190 return QualType(); 3191 } 3192 // We have 2 block pointer types. 3193 if (Context.getCanonicalType(LHSTy) == Context.getCanonicalType(RHSTy)) { 3194 // Two identical block pointer types are always compatible. 3195 return LHSTy; 3196 } 3197 // The block pointer types aren't identical, continue checking. 3198 QualType lhptee = LHSTy->getAs<BlockPointerType>()->getPointeeType(); 3199 QualType rhptee = RHSTy->getAs<BlockPointerType>()->getPointeeType(); 3200 3201 if (!Context.typesAreCompatible(lhptee.getUnqualifiedType(), 3202 rhptee.getUnqualifiedType())) { 3203 Diag(QuestionLoc, diag::warn_typecheck_cond_incompatible_pointers) 3204 << LHSTy << RHSTy << LHS->getSourceRange() << RHS->getSourceRange(); 3205 // In this situation, we assume void* type. No especially good 3206 // reason, but this is what gcc does, and we do have to pick 3207 // to get a consistent AST. 3208 QualType incompatTy = Context.getPointerType(Context.VoidTy); 3209 ImpCastExprToType(LHS, incompatTy); 3210 ImpCastExprToType(RHS, incompatTy); 3211 return incompatTy; 3212 } 3213 // The block pointer types are compatible. 3214 ImpCastExprToType(LHS, LHSTy); 3215 ImpCastExprToType(RHS, LHSTy); 3216 return LHSTy; 3217 } 3218 // Check constraints for Objective-C object pointers types. 3219 if (LHSTy->isObjCObjectPointerType() && RHSTy->isObjCObjectPointerType()) { 3220 3221 if (Context.getCanonicalType(LHSTy) == Context.getCanonicalType(RHSTy)) { 3222 // Two identical object pointer types are always compatible. 3223 return LHSTy; 3224 } 3225 const ObjCObjectPointerType *LHSOPT = LHSTy->getAsObjCObjectPointerType(); 3226 const ObjCObjectPointerType *RHSOPT = RHSTy->getAsObjCObjectPointerType(); 3227 QualType compositeType = LHSTy; 3228 3229 // If both operands are interfaces and either operand can be 3230 // assigned to the other, use that type as the composite 3231 // type. This allows 3232 // xxx ? (A*) a : (B*) b 3233 // where B is a subclass of A. 3234 // 3235 // Additionally, as for assignment, if either type is 'id' 3236 // allow silent coercion. Finally, if the types are 3237 // incompatible then make sure to use 'id' as the composite 3238 // type so the result is acceptable for sending messages to. 3239 3240 // FIXME: Consider unifying with 'areComparableObjCPointerTypes'. 3241 // It could return the composite type. 3242 if (Context.canAssignObjCInterfaces(LHSOPT, RHSOPT)) { 3243 compositeType = LHSTy; 3244 } else if (Context.canAssignObjCInterfaces(RHSOPT, LHSOPT)) { 3245 compositeType = RHSTy; 3246 } else if ((LHSTy->isObjCQualifiedIdType() || 3247 RHSTy->isObjCQualifiedIdType()) && 3248 Context.ObjCQualifiedIdTypesAreCompatible(LHSTy, RHSTy, true)) { 3249 // Need to handle "id<xx>" explicitly. 3250 // GCC allows qualified id and any Objective-C type to devolve to 3251 // id. Currently localizing to here until clear this should be 3252 // part of ObjCQualifiedIdTypesAreCompatible. 3253 compositeType = Context.getObjCIdType(); 3254 } else if (LHSTy->isObjCIdType() || RHSTy->isObjCIdType()) { 3255 compositeType = Context.getObjCIdType(); 3256 } else { 3257 Diag(QuestionLoc, diag::ext_typecheck_cond_incompatible_operands) 3258 << LHSTy << RHSTy 3259 << LHS->getSourceRange() << RHS->getSourceRange(); 3260 QualType incompatTy = Context.getObjCIdType(); 3261 ImpCastExprToType(LHS, incompatTy); 3262 ImpCastExprToType(RHS, incompatTy); 3263 return incompatTy; 3264 } 3265 // The object pointer types are compatible. 3266 ImpCastExprToType(LHS, compositeType); 3267 ImpCastExprToType(RHS, compositeType); 3268 return compositeType; 3269 } 3270 // Check Objective-C object pointer types and 'void *' 3271 if (LHSTy->isVoidPointerType() && RHSTy->isObjCObjectPointerType()) { 3272 QualType lhptee = LHSTy->getAs<PointerType>()->getPointeeType(); 3273 QualType rhptee = RHSTy->getAsObjCObjectPointerType()->getPointeeType(); 3274 QualType destPointee = lhptee.getQualifiedType(rhptee.getCVRQualifiers()); 3275 QualType destType = Context.getPointerType(destPointee); 3276 ImpCastExprToType(LHS, destType); // add qualifiers if necessary 3277 ImpCastExprToType(RHS, destType); // promote to void* 3278 return destType; 3279 } 3280 if (LHSTy->isObjCObjectPointerType() && RHSTy->isVoidPointerType()) { 3281 QualType lhptee = LHSTy->getAsObjCObjectPointerType()->getPointeeType(); 3282 QualType rhptee = RHSTy->getAs<PointerType>()->getPointeeType(); 3283 QualType destPointee = rhptee.getQualifiedType(lhptee.getCVRQualifiers()); 3284 QualType destType = Context.getPointerType(destPointee); 3285 ImpCastExprToType(RHS, destType); // add qualifiers if necessary 3286 ImpCastExprToType(LHS, destType); // promote to void* 3287 return destType; 3288 } 3289 // Check constraints for C object pointers types (C99 6.5.15p3,6). 3290 if (LHSTy->isPointerType() && RHSTy->isPointerType()) { 3291 // get the "pointed to" types 3292 QualType lhptee = LHSTy->getAs<PointerType>()->getPointeeType(); 3293 QualType rhptee = RHSTy->getAs<PointerType>()->getPointeeType(); 3294 3295 // ignore qualifiers on void (C99 6.5.15p3, clause 6) 3296 if (lhptee->isVoidType() && rhptee->isIncompleteOrObjectType()) { 3297 // Figure out necessary qualifiers (C99 6.5.15p6) 3298 QualType destPointee=lhptee.getQualifiedType(rhptee.getCVRQualifiers()); 3299 QualType destType = Context.getPointerType(destPointee); 3300 ImpCastExprToType(LHS, destType); // add qualifiers if necessary 3301 ImpCastExprToType(RHS, destType); // promote to void* 3302 return destType; 3303 } 3304 if (rhptee->isVoidType() && lhptee->isIncompleteOrObjectType()) { 3305 QualType destPointee=rhptee.getQualifiedType(lhptee.getCVRQualifiers()); 3306 QualType destType = Context.getPointerType(destPointee); 3307 ImpCastExprToType(LHS, destType); // add qualifiers if necessary 3308 ImpCastExprToType(RHS, destType); // promote to void* 3309 return destType; 3310 } 3311 3312 if (Context.getCanonicalType(LHSTy) == Context.getCanonicalType(RHSTy)) { 3313 // Two identical pointer types are always compatible. 3314 return LHSTy; 3315 } 3316 if (!Context.typesAreCompatible(lhptee.getUnqualifiedType(), 3317 rhptee.getUnqualifiedType())) { 3318 Diag(QuestionLoc, diag::warn_typecheck_cond_incompatible_pointers) 3319 << LHSTy << RHSTy << LHS->getSourceRange() << RHS->getSourceRange(); 3320 // In this situation, we assume void* type. No especially good 3321 // reason, but this is what gcc does, and we do have to pick 3322 // to get a consistent AST. 3323 QualType incompatTy = Context.getPointerType(Context.VoidTy); 3324 ImpCastExprToType(LHS, incompatTy); 3325 ImpCastExprToType(RHS, incompatTy); 3326 return incompatTy; 3327 } 3328 // The pointer types are compatible. 3329 // C99 6.5.15p6: If both operands are pointers to compatible types *or* to 3330 // differently qualified versions of compatible types, the result type is 3331 // a pointer to an appropriately qualified version of the *composite* 3332 // type. 3333 // FIXME: Need to calculate the composite type. 3334 // FIXME: Need to add qualifiers 3335 ImpCastExprToType(LHS, LHSTy); 3336 ImpCastExprToType(RHS, LHSTy); 3337 return LHSTy; 3338 } 3339 3340 // GCC compatibility: soften pointer/integer mismatch. 3341 if (RHSTy->isPointerType() && LHSTy->isIntegerType()) { 3342 Diag(QuestionLoc, diag::warn_typecheck_cond_pointer_integer_mismatch) 3343 << LHSTy << RHSTy << LHS->getSourceRange() << RHS->getSourceRange(); 3344 ImpCastExprToType(LHS, RHSTy); // promote the integer to a pointer. 3345 return RHSTy; 3346 } 3347 if (LHSTy->isPointerType() && RHSTy->isIntegerType()) { 3348 Diag(QuestionLoc, diag::warn_typecheck_cond_pointer_integer_mismatch) 3349 << LHSTy << RHSTy << LHS->getSourceRange() << RHS->getSourceRange(); 3350 ImpCastExprToType(RHS, LHSTy); // promote the integer to a pointer. 3351 return LHSTy; 3352 } 3353 3354 // Otherwise, the operands are not compatible. 3355 Diag(QuestionLoc, diag::err_typecheck_cond_incompatible_operands) 3356 << LHSTy << RHSTy << LHS->getSourceRange() << RHS->getSourceRange(); 3357 return QualType(); 3358} 3359 3360/// ActOnConditionalOp - Parse a ?: operation. Note that 'LHS' may be null 3361/// in the case of a the GNU conditional expr extension. 3362Action::OwningExprResult Sema::ActOnConditionalOp(SourceLocation QuestionLoc, 3363 SourceLocation ColonLoc, 3364 ExprArg Cond, ExprArg LHS, 3365 ExprArg RHS) { 3366 Expr *CondExpr = (Expr *) Cond.get(); 3367 Expr *LHSExpr = (Expr *) LHS.get(), *RHSExpr = (Expr *) RHS.get(); 3368 3369 // If this is the gnu "x ?: y" extension, analyze the types as though the LHS 3370 // was the condition. 3371 bool isLHSNull = LHSExpr == 0; 3372 if (isLHSNull) 3373 LHSExpr = CondExpr; 3374 3375 QualType result = CheckConditionalOperands(CondExpr, LHSExpr, 3376 RHSExpr, QuestionLoc); 3377 if (result.isNull()) 3378 return ExprError(); 3379 3380 Cond.release(); 3381 LHS.release(); 3382 RHS.release(); 3383 return Owned(new (Context) ConditionalOperator(CondExpr, 3384 isLHSNull ? 0 : LHSExpr, 3385 RHSExpr, result)); 3386} 3387 3388// CheckPointerTypesForAssignment - This is a very tricky routine (despite 3389// being closely modeled after the C99 spec:-). The odd characteristic of this 3390// routine is it effectively iqnores the qualifiers on the top level pointee. 3391// This circumvents the usual type rules specified in 6.2.7p1 & 6.7.5.[1-3]. 3392// FIXME: add a couple examples in this comment. 3393Sema::AssignConvertType 3394Sema::CheckPointerTypesForAssignment(QualType lhsType, QualType rhsType) { 3395 QualType lhptee, rhptee; 3396 3397 // get the "pointed to" type (ignoring qualifiers at the top level) 3398 lhptee = lhsType->getAs<PointerType>()->getPointeeType(); 3399 rhptee = rhsType->getAs<PointerType>()->getPointeeType(); 3400 3401 // make sure we operate on the canonical type 3402 lhptee = Context.getCanonicalType(lhptee); 3403 rhptee = Context.getCanonicalType(rhptee); 3404 3405 AssignConvertType ConvTy = Compatible; 3406 3407 // C99 6.5.16.1p1: This following citation is common to constraints 3408 // 3 & 4 (below). ...and the type *pointed to* by the left has all the 3409 // qualifiers of the type *pointed to* by the right; 3410 // FIXME: Handle ExtQualType 3411 if (!lhptee.isAtLeastAsQualifiedAs(rhptee)) 3412 ConvTy = CompatiblePointerDiscardsQualifiers; 3413 3414 // C99 6.5.16.1p1 (constraint 4): If one operand is a pointer to an object or 3415 // incomplete type and the other is a pointer to a qualified or unqualified 3416 // version of void... 3417 if (lhptee->isVoidType()) { 3418 if (rhptee->isIncompleteOrObjectType()) 3419 return ConvTy; 3420 3421 // As an extension, we allow cast to/from void* to function pointer. 3422 assert(rhptee->isFunctionType()); 3423 return FunctionVoidPointer; 3424 } 3425 3426 if (rhptee->isVoidType()) { 3427 if (lhptee->isIncompleteOrObjectType()) 3428 return ConvTy; 3429 3430 // As an extension, we allow cast to/from void* to function pointer. 3431 assert(lhptee->isFunctionType()); 3432 return FunctionVoidPointer; 3433 } 3434 // C99 6.5.16.1p1 (constraint 3): both operands are pointers to qualified or 3435 // unqualified versions of compatible types, ... 3436 lhptee = lhptee.getUnqualifiedType(); 3437 rhptee = rhptee.getUnqualifiedType(); 3438 if (!Context.typesAreCompatible(lhptee, rhptee)) { 3439 // Check if the pointee types are compatible ignoring the sign. 3440 // We explicitly check for char so that we catch "char" vs 3441 // "unsigned char" on systems where "char" is unsigned. 3442 if (lhptee->isCharType()) { 3443 lhptee = Context.UnsignedCharTy; 3444 } else if (lhptee->isSignedIntegerType()) { 3445 lhptee = Context.getCorrespondingUnsignedType(lhptee); 3446 } 3447 if (rhptee->isCharType()) { 3448 rhptee = Context.UnsignedCharTy; 3449 } else if (rhptee->isSignedIntegerType()) { 3450 rhptee = Context.getCorrespondingUnsignedType(rhptee); 3451 } 3452 if (lhptee == rhptee) { 3453 // Types are compatible ignoring the sign. Qualifier incompatibility 3454 // takes priority over sign incompatibility because the sign 3455 // warning can be disabled. 3456 if (ConvTy != Compatible) 3457 return ConvTy; 3458 return IncompatiblePointerSign; 3459 } 3460 // General pointer incompatibility takes priority over qualifiers. 3461 return IncompatiblePointer; 3462 } 3463 return ConvTy; 3464} 3465 3466/// CheckBlockPointerTypesForAssignment - This routine determines whether two 3467/// block pointer types are compatible or whether a block and normal pointer 3468/// are compatible. It is more restrict than comparing two function pointer 3469// types. 3470Sema::AssignConvertType 3471Sema::CheckBlockPointerTypesForAssignment(QualType lhsType, 3472 QualType rhsType) { 3473 QualType lhptee, rhptee; 3474 3475 // get the "pointed to" type (ignoring qualifiers at the top level) 3476 lhptee = lhsType->getAs<BlockPointerType>()->getPointeeType(); 3477 rhptee = rhsType->getAs<BlockPointerType>()->getPointeeType(); 3478 3479 // make sure we operate on the canonical type 3480 lhptee = Context.getCanonicalType(lhptee); 3481 rhptee = Context.getCanonicalType(rhptee); 3482 3483 AssignConvertType ConvTy = Compatible; 3484 3485 // For blocks we enforce that qualifiers are identical. 3486 if (lhptee.getCVRQualifiers() != rhptee.getCVRQualifiers()) 3487 ConvTy = CompatiblePointerDiscardsQualifiers; 3488 3489 if (!Context.typesAreCompatible(lhptee, rhptee)) 3490 return IncompatibleBlockPointer; 3491 return ConvTy; 3492} 3493 3494/// CheckAssignmentConstraints (C99 6.5.16) - This routine currently 3495/// has code to accommodate several GCC extensions when type checking 3496/// pointers. Here are some objectionable examples that GCC considers warnings: 3497/// 3498/// int a, *pint; 3499/// short *pshort; 3500/// struct foo *pfoo; 3501/// 3502/// pint = pshort; // warning: assignment from incompatible pointer type 3503/// a = pint; // warning: assignment makes integer from pointer without a cast 3504/// pint = a; // warning: assignment makes pointer from integer without a cast 3505/// pint = pfoo; // warning: assignment from incompatible pointer type 3506/// 3507/// As a result, the code for dealing with pointers is more complex than the 3508/// C99 spec dictates. 3509/// 3510Sema::AssignConvertType 3511Sema::CheckAssignmentConstraints(QualType lhsType, QualType rhsType) { 3512 // Get canonical types. We're not formatting these types, just comparing 3513 // them. 3514 lhsType = Context.getCanonicalType(lhsType).getUnqualifiedType(); 3515 rhsType = Context.getCanonicalType(rhsType).getUnqualifiedType(); 3516 3517 if (lhsType == rhsType) 3518 return Compatible; // Common case: fast path an exact match. 3519 3520 // If the left-hand side is a reference type, then we are in a 3521 // (rare!) case where we've allowed the use of references in C, 3522 // e.g., as a parameter type in a built-in function. In this case, 3523 // just make sure that the type referenced is compatible with the 3524 // right-hand side type. The caller is responsible for adjusting 3525 // lhsType so that the resulting expression does not have reference 3526 // type. 3527 if (const ReferenceType *lhsTypeRef = lhsType->getAs<ReferenceType>()) { 3528 if (Context.typesAreCompatible(lhsTypeRef->getPointeeType(), rhsType)) 3529 return Compatible; 3530 return Incompatible; 3531 } 3532 // Allow scalar to ExtVector assignments, and assignments of an ExtVector type 3533 // to the same ExtVector type. 3534 if (lhsType->isExtVectorType()) { 3535 if (rhsType->isExtVectorType()) 3536 return lhsType == rhsType ? Compatible : Incompatible; 3537 if (!rhsType->isVectorType() && rhsType->isArithmeticType()) 3538 return Compatible; 3539 } 3540 3541 if (lhsType->isVectorType() || rhsType->isVectorType()) { 3542 // If we are allowing lax vector conversions, and LHS and RHS are both 3543 // vectors, the total size only needs to be the same. This is a bitcast; 3544 // no bits are changed but the result type is different. 3545 if (getLangOptions().LaxVectorConversions && 3546 lhsType->isVectorType() && rhsType->isVectorType()) { 3547 if (Context.getTypeSize(lhsType) == Context.getTypeSize(rhsType)) 3548 return IncompatibleVectors; 3549 } 3550 return Incompatible; 3551 } 3552 3553 if (lhsType->isArithmeticType() && rhsType->isArithmeticType()) 3554 return Compatible; 3555 3556 if (isa<PointerType>(lhsType)) { 3557 if (rhsType->isIntegerType()) 3558 return IntToPointer; 3559 3560 if (isa<PointerType>(rhsType)) 3561 return CheckPointerTypesForAssignment(lhsType, rhsType); 3562 3563 // In general, C pointers are not compatible with ObjC object pointers. 3564 if (isa<ObjCObjectPointerType>(rhsType)) { 3565 if (lhsType->isVoidPointerType()) // an exception to the rule. 3566 return Compatible; 3567 return IncompatiblePointer; 3568 } 3569 if (rhsType->getAs<BlockPointerType>()) { 3570 if (lhsType->getAs<PointerType>()->getPointeeType()->isVoidType()) 3571 return Compatible; 3572 3573 // Treat block pointers as objects. 3574 if (getLangOptions().ObjC1 && lhsType->isObjCIdType()) 3575 return Compatible; 3576 } 3577 return Incompatible; 3578 } 3579 3580 if (isa<BlockPointerType>(lhsType)) { 3581 if (rhsType->isIntegerType()) 3582 return IntToBlockPointer; 3583 3584 // Treat block pointers as objects. 3585 if (getLangOptions().ObjC1 && rhsType->isObjCIdType()) 3586 return Compatible; 3587 3588 if (rhsType->isBlockPointerType()) 3589 return CheckBlockPointerTypesForAssignment(lhsType, rhsType); 3590 3591 if (const PointerType *RHSPT = rhsType->getAs<PointerType>()) { 3592 if (RHSPT->getPointeeType()->isVoidType()) 3593 return Compatible; 3594 } 3595 return Incompatible; 3596 } 3597 3598 if (isa<ObjCObjectPointerType>(lhsType)) { 3599 if (rhsType->isIntegerType()) 3600 return IntToPointer; 3601 3602 // In general, C pointers are not compatible with ObjC object pointers. 3603 if (isa<PointerType>(rhsType)) { 3604 if (rhsType->isVoidPointerType()) // an exception to the rule. 3605 return Compatible; 3606 return IncompatiblePointer; 3607 } 3608 if (rhsType->isObjCObjectPointerType()) { 3609 if (lhsType->isObjCBuiltinType() || rhsType->isObjCBuiltinType()) 3610 return Compatible; 3611 if (Context.typesAreCompatible(lhsType, rhsType)) 3612 return Compatible; 3613 if (lhsType->isObjCQualifiedIdType() || rhsType->isObjCQualifiedIdType()) 3614 return IncompatibleObjCQualifiedId; 3615 return IncompatiblePointer; 3616 } 3617 if (const PointerType *RHSPT = rhsType->getAs<PointerType>()) { 3618 if (RHSPT->getPointeeType()->isVoidType()) 3619 return Compatible; 3620 } 3621 // Treat block pointers as objects. 3622 if (rhsType->isBlockPointerType()) 3623 return Compatible; 3624 return Incompatible; 3625 } 3626 if (isa<PointerType>(rhsType)) { 3627 // C99 6.5.16.1p1: the left operand is _Bool and the right is a pointer. 3628 if (lhsType == Context.BoolTy) 3629 return Compatible; 3630 3631 if (lhsType->isIntegerType()) 3632 return PointerToInt; 3633 3634 if (isa<PointerType>(lhsType)) 3635 return CheckPointerTypesForAssignment(lhsType, rhsType); 3636 3637 if (isa<BlockPointerType>(lhsType) && 3638 rhsType->getAs<PointerType>()->getPointeeType()->isVoidType()) 3639 return Compatible; 3640 return Incompatible; 3641 } 3642 if (isa<ObjCObjectPointerType>(rhsType)) { 3643 // C99 6.5.16.1p1: the left operand is _Bool and the right is a pointer. 3644 if (lhsType == Context.BoolTy) 3645 return Compatible; 3646 3647 if (lhsType->isIntegerType()) 3648 return PointerToInt; 3649 3650 // In general, C pointers are not compatible with ObjC object pointers. 3651 if (isa<PointerType>(lhsType)) { 3652 if (lhsType->isVoidPointerType()) // an exception to the rule. 3653 return Compatible; 3654 return IncompatiblePointer; 3655 } 3656 if (isa<BlockPointerType>(lhsType) && 3657 rhsType->getAs<PointerType>()->getPointeeType()->isVoidType()) 3658 return Compatible; 3659 return Incompatible; 3660 } 3661 3662 if (isa<TagType>(lhsType) && isa<TagType>(rhsType)) { 3663 if (Context.typesAreCompatible(lhsType, rhsType)) 3664 return Compatible; 3665 } 3666 return Incompatible; 3667} 3668 3669/// \brief Constructs a transparent union from an expression that is 3670/// used to initialize the transparent union. 3671static void ConstructTransparentUnion(ASTContext &C, Expr *&E, 3672 QualType UnionType, FieldDecl *Field) { 3673 // Build an initializer list that designates the appropriate member 3674 // of the transparent union. 3675 InitListExpr *Initializer = new (C) InitListExpr(SourceLocation(), 3676 &E, 1, 3677 SourceLocation()); 3678 Initializer->setType(UnionType); 3679 Initializer->setInitializedFieldInUnion(Field); 3680 3681 // Build a compound literal constructing a value of the transparent 3682 // union type from this initializer list. 3683 E = new (C) CompoundLiteralExpr(SourceLocation(), UnionType, Initializer, 3684 false); 3685} 3686 3687Sema::AssignConvertType 3688Sema::CheckTransparentUnionArgumentConstraints(QualType ArgType, Expr *&rExpr) { 3689 QualType FromType = rExpr->getType(); 3690 3691 // If the ArgType is a Union type, we want to handle a potential 3692 // transparent_union GCC extension. 3693 const RecordType *UT = ArgType->getAsUnionType(); 3694 if (!UT || !UT->getDecl()->hasAttr<TransparentUnionAttr>()) 3695 return Incompatible; 3696 3697 // The field to initialize within the transparent union. 3698 RecordDecl *UD = UT->getDecl(); 3699 FieldDecl *InitField = 0; 3700 // It's compatible if the expression matches any of the fields. 3701 for (RecordDecl::field_iterator it = UD->field_begin(), 3702 itend = UD->field_end(); 3703 it != itend; ++it) { 3704 if (it->getType()->isPointerType()) { 3705 // If the transparent union contains a pointer type, we allow: 3706 // 1) void pointer 3707 // 2) null pointer constant 3708 if (FromType->isPointerType()) 3709 if (FromType->getAs<PointerType>()->getPointeeType()->isVoidType()) { 3710 ImpCastExprToType(rExpr, it->getType()); 3711 InitField = *it; 3712 break; 3713 } 3714 3715 if (rExpr->isNullPointerConstant(Context)) { 3716 ImpCastExprToType(rExpr, it->getType()); 3717 InitField = *it; 3718 break; 3719 } 3720 } 3721 3722 if (CheckAssignmentConstraints(it->getType(), rExpr->getType()) 3723 == Compatible) { 3724 InitField = *it; 3725 break; 3726 } 3727 } 3728 3729 if (!InitField) 3730 return Incompatible; 3731 3732 ConstructTransparentUnion(Context, rExpr, ArgType, InitField); 3733 return Compatible; 3734} 3735 3736Sema::AssignConvertType 3737Sema::CheckSingleAssignmentConstraints(QualType lhsType, Expr *&rExpr) { 3738 if (getLangOptions().CPlusPlus) { 3739 if (!lhsType->isRecordType()) { 3740 // C++ 5.17p3: If the left operand is not of class type, the 3741 // expression is implicitly converted (C++ 4) to the 3742 // cv-unqualified type of the left operand. 3743 if (PerformImplicitConversion(rExpr, lhsType.getUnqualifiedType(), 3744 "assigning")) 3745 return Incompatible; 3746 return Compatible; 3747 } 3748 3749 // FIXME: Currently, we fall through and treat C++ classes like C 3750 // structures. 3751 } 3752 3753 // C99 6.5.16.1p1: the left operand is a pointer and the right is 3754 // a null pointer constant. 3755 if ((lhsType->isPointerType() || 3756 lhsType->isObjCObjectPointerType() || 3757 lhsType->isBlockPointerType()) 3758 && rExpr->isNullPointerConstant(Context)) { 3759 ImpCastExprToType(rExpr, lhsType); 3760 return Compatible; 3761 } 3762 3763 // This check seems unnatural, however it is necessary to ensure the proper 3764 // conversion of functions/arrays. If the conversion were done for all 3765 // DeclExpr's (created by ActOnIdentifierExpr), it would mess up the unary 3766 // expressions that surpress this implicit conversion (&, sizeof). 3767 // 3768 // Suppress this for references: C++ 8.5.3p5. 3769 if (!lhsType->isReferenceType()) 3770 DefaultFunctionArrayConversion(rExpr); 3771 3772 Sema::AssignConvertType result = 3773 CheckAssignmentConstraints(lhsType, rExpr->getType()); 3774 3775 // C99 6.5.16.1p2: The value of the right operand is converted to the 3776 // type of the assignment expression. 3777 // CheckAssignmentConstraints allows the left-hand side to be a reference, 3778 // so that we can use references in built-in functions even in C. 3779 // The getNonReferenceType() call makes sure that the resulting expression 3780 // does not have reference type. 3781 if (result != Incompatible && rExpr->getType() != lhsType) 3782 ImpCastExprToType(rExpr, lhsType.getNonReferenceType()); 3783 return result; 3784} 3785 3786QualType Sema::InvalidOperands(SourceLocation Loc, Expr *&lex, Expr *&rex) { 3787 Diag(Loc, diag::err_typecheck_invalid_operands) 3788 << lex->getType() << rex->getType() 3789 << lex->getSourceRange() << rex->getSourceRange(); 3790 return QualType(); 3791} 3792 3793inline QualType Sema::CheckVectorOperands(SourceLocation Loc, Expr *&lex, 3794 Expr *&rex) { 3795 // For conversion purposes, we ignore any qualifiers. 3796 // For example, "const float" and "float" are equivalent. 3797 QualType lhsType = 3798 Context.getCanonicalType(lex->getType()).getUnqualifiedType(); 3799 QualType rhsType = 3800 Context.getCanonicalType(rex->getType()).getUnqualifiedType(); 3801 3802 // If the vector types are identical, return. 3803 if (lhsType == rhsType) 3804 return lhsType; 3805 3806 // Handle the case of a vector & extvector type of the same size and element 3807 // type. It would be nice if we only had one vector type someday. 3808 if (getLangOptions().LaxVectorConversions) { 3809 // FIXME: Should we warn here? 3810 if (const VectorType *LV = lhsType->getAsVectorType()) { 3811 if (const VectorType *RV = rhsType->getAsVectorType()) 3812 if (LV->getElementType() == RV->getElementType() && 3813 LV->getNumElements() == RV->getNumElements()) { 3814 return lhsType->isExtVectorType() ? lhsType : rhsType; 3815 } 3816 } 3817 } 3818 3819 // Canonicalize the ExtVector to the LHS, remember if we swapped so we can 3820 // swap back (so that we don't reverse the inputs to a subtract, for instance. 3821 bool swapped = false; 3822 if (rhsType->isExtVectorType()) { 3823 swapped = true; 3824 std::swap(rex, lex); 3825 std::swap(rhsType, lhsType); 3826 } 3827 3828 // Handle the case of an ext vector and scalar. 3829 if (const ExtVectorType *LV = lhsType->getAsExtVectorType()) { 3830 QualType EltTy = LV->getElementType(); 3831 if (EltTy->isIntegralType() && rhsType->isIntegralType()) { 3832 if (Context.getIntegerTypeOrder(EltTy, rhsType) >= 0) { 3833 ImpCastExprToType(rex, lhsType); 3834 if (swapped) std::swap(rex, lex); 3835 return lhsType; 3836 } 3837 } 3838 if (EltTy->isRealFloatingType() && rhsType->isScalarType() && 3839 rhsType->isRealFloatingType()) { 3840 if (Context.getFloatingTypeOrder(EltTy, rhsType) >= 0) { 3841 ImpCastExprToType(rex, lhsType); 3842 if (swapped) std::swap(rex, lex); 3843 return lhsType; 3844 } 3845 } 3846 } 3847 3848 // Vectors of different size or scalar and non-ext-vector are errors. 3849 Diag(Loc, diag::err_typecheck_vector_not_convertable) 3850 << lex->getType() << rex->getType() 3851 << lex->getSourceRange() << rex->getSourceRange(); 3852 return QualType(); 3853} 3854 3855inline QualType Sema::CheckMultiplyDivideOperands( 3856 Expr *&lex, Expr *&rex, SourceLocation Loc, bool isCompAssign) 3857{ 3858 if (lex->getType()->isVectorType() || rex->getType()->isVectorType()) 3859 return CheckVectorOperands(Loc, lex, rex); 3860 3861 QualType compType = UsualArithmeticConversions(lex, rex, isCompAssign); 3862 3863 if (lex->getType()->isArithmeticType() && rex->getType()->isArithmeticType()) 3864 return compType; 3865 return InvalidOperands(Loc, lex, rex); 3866} 3867 3868inline QualType Sema::CheckRemainderOperands( 3869 Expr *&lex, Expr *&rex, SourceLocation Loc, bool isCompAssign) 3870{ 3871 if (lex->getType()->isVectorType() || rex->getType()->isVectorType()) { 3872 if (lex->getType()->isIntegerType() && rex->getType()->isIntegerType()) 3873 return CheckVectorOperands(Loc, lex, rex); 3874 return InvalidOperands(Loc, lex, rex); 3875 } 3876 3877 QualType compType = UsualArithmeticConversions(lex, rex, isCompAssign); 3878 3879 if (lex->getType()->isIntegerType() && rex->getType()->isIntegerType()) 3880 return compType; 3881 return InvalidOperands(Loc, lex, rex); 3882} 3883 3884inline QualType Sema::CheckAdditionOperands( // C99 6.5.6 3885 Expr *&lex, Expr *&rex, SourceLocation Loc, QualType* CompLHSTy) 3886{ 3887 if (lex->getType()->isVectorType() || rex->getType()->isVectorType()) { 3888 QualType compType = CheckVectorOperands(Loc, lex, rex); 3889 if (CompLHSTy) *CompLHSTy = compType; 3890 return compType; 3891 } 3892 3893 QualType compType = UsualArithmeticConversions(lex, rex, CompLHSTy); 3894 3895 // handle the common case first (both operands are arithmetic). 3896 if (lex->getType()->isArithmeticType() && 3897 rex->getType()->isArithmeticType()) { 3898 if (CompLHSTy) *CompLHSTy = compType; 3899 return compType; 3900 } 3901 3902 // Put any potential pointer into PExp 3903 Expr* PExp = lex, *IExp = rex; 3904 if (IExp->getType()->isAnyPointerType()) 3905 std::swap(PExp, IExp); 3906 3907 if (PExp->getType()->isAnyPointerType()) { 3908 3909 if (IExp->getType()->isIntegerType()) { 3910 QualType PointeeTy = PExp->getType()->getPointeeType(); 3911 3912 // Check for arithmetic on pointers to incomplete types. 3913 if (PointeeTy->isVoidType()) { 3914 if (getLangOptions().CPlusPlus) { 3915 Diag(Loc, diag::err_typecheck_pointer_arith_void_type) 3916 << lex->getSourceRange() << rex->getSourceRange(); 3917 return QualType(); 3918 } 3919 3920 // GNU extension: arithmetic on pointer to void 3921 Diag(Loc, diag::ext_gnu_void_ptr) 3922 << lex->getSourceRange() << rex->getSourceRange(); 3923 } else if (PointeeTy->isFunctionType()) { 3924 if (getLangOptions().CPlusPlus) { 3925 Diag(Loc, diag::err_typecheck_pointer_arith_function_type) 3926 << lex->getType() << lex->getSourceRange(); 3927 return QualType(); 3928 } 3929 3930 // GNU extension: arithmetic on pointer to function 3931 Diag(Loc, diag::ext_gnu_ptr_func_arith) 3932 << lex->getType() << lex->getSourceRange(); 3933 } else { 3934 // Check if we require a complete type. 3935 if (((PExp->getType()->isPointerType() && 3936 !PExp->getType()->isDependentType()) || 3937 PExp->getType()->isObjCObjectPointerType()) && 3938 RequireCompleteType(Loc, PointeeTy, 3939 diag::err_typecheck_arithmetic_incomplete_type, 3940 PExp->getSourceRange(), SourceRange(), 3941 PExp->getType())) 3942 return QualType(); 3943 } 3944 // Diagnose bad cases where we step over interface counts. 3945 if (PointeeTy->isObjCInterfaceType() && LangOpts.ObjCNonFragileABI) { 3946 Diag(Loc, diag::err_arithmetic_nonfragile_interface) 3947 << PointeeTy << PExp->getSourceRange(); 3948 return QualType(); 3949 } 3950 3951 if (CompLHSTy) { 3952 QualType LHSTy = lex->getType(); 3953 if (LHSTy->isPromotableIntegerType()) 3954 LHSTy = Context.IntTy; 3955 else { 3956 QualType T = isPromotableBitField(lex, Context); 3957 if (!T.isNull()) 3958 LHSTy = T; 3959 } 3960 3961 *CompLHSTy = LHSTy; 3962 } 3963 return PExp->getType(); 3964 } 3965 } 3966 3967 return InvalidOperands(Loc, lex, rex); 3968} 3969 3970// C99 6.5.6 3971QualType Sema::CheckSubtractionOperands(Expr *&lex, Expr *&rex, 3972 SourceLocation Loc, QualType* CompLHSTy) { 3973 if (lex->getType()->isVectorType() || rex->getType()->isVectorType()) { 3974 QualType compType = CheckVectorOperands(Loc, lex, rex); 3975 if (CompLHSTy) *CompLHSTy = compType; 3976 return compType; 3977 } 3978 3979 QualType compType = UsualArithmeticConversions(lex, rex, CompLHSTy); 3980 3981 // Enforce type constraints: C99 6.5.6p3. 3982 3983 // Handle the common case first (both operands are arithmetic). 3984 if (lex->getType()->isArithmeticType() 3985 && rex->getType()->isArithmeticType()) { 3986 if (CompLHSTy) *CompLHSTy = compType; 3987 return compType; 3988 } 3989 3990 // Either ptr - int or ptr - ptr. 3991 if (lex->getType()->isAnyPointerType()) { 3992 QualType lpointee = lex->getType()->getPointeeType(); 3993 3994 // The LHS must be an completely-defined object type. 3995 3996 bool ComplainAboutVoid = false; 3997 Expr *ComplainAboutFunc = 0; 3998 if (lpointee->isVoidType()) { 3999 if (getLangOptions().CPlusPlus) { 4000 Diag(Loc, diag::err_typecheck_pointer_arith_void_type) 4001 << lex->getSourceRange() << rex->getSourceRange(); 4002 return QualType(); 4003 } 4004 4005 // GNU C extension: arithmetic on pointer to void 4006 ComplainAboutVoid = true; 4007 } else if (lpointee->isFunctionType()) { 4008 if (getLangOptions().CPlusPlus) { 4009 Diag(Loc, diag::err_typecheck_pointer_arith_function_type) 4010 << lex->getType() << lex->getSourceRange(); 4011 return QualType(); 4012 } 4013 4014 // GNU C extension: arithmetic on pointer to function 4015 ComplainAboutFunc = lex; 4016 } else if (!lpointee->isDependentType() && 4017 RequireCompleteType(Loc, lpointee, 4018 diag::err_typecheck_sub_ptr_object, 4019 lex->getSourceRange(), 4020 SourceRange(), 4021 lex->getType())) 4022 return QualType(); 4023 4024 // Diagnose bad cases where we step over interface counts. 4025 if (lpointee->isObjCInterfaceType() && LangOpts.ObjCNonFragileABI) { 4026 Diag(Loc, diag::err_arithmetic_nonfragile_interface) 4027 << lpointee << lex->getSourceRange(); 4028 return QualType(); 4029 } 4030 4031 // The result type of a pointer-int computation is the pointer type. 4032 if (rex->getType()->isIntegerType()) { 4033 if (ComplainAboutVoid) 4034 Diag(Loc, diag::ext_gnu_void_ptr) 4035 << lex->getSourceRange() << rex->getSourceRange(); 4036 if (ComplainAboutFunc) 4037 Diag(Loc, diag::ext_gnu_ptr_func_arith) 4038 << ComplainAboutFunc->getType() 4039 << ComplainAboutFunc->getSourceRange(); 4040 4041 if (CompLHSTy) *CompLHSTy = lex->getType(); 4042 return lex->getType(); 4043 } 4044 4045 // Handle pointer-pointer subtractions. 4046 if (const PointerType *RHSPTy = rex->getType()->getAs<PointerType>()) { 4047 QualType rpointee = RHSPTy->getPointeeType(); 4048 4049 // RHS must be a completely-type object type. 4050 // Handle the GNU void* extension. 4051 if (rpointee->isVoidType()) { 4052 if (getLangOptions().CPlusPlus) { 4053 Diag(Loc, diag::err_typecheck_pointer_arith_void_type) 4054 << lex->getSourceRange() << rex->getSourceRange(); 4055 return QualType(); 4056 } 4057 4058 ComplainAboutVoid = true; 4059 } else if (rpointee->isFunctionType()) { 4060 if (getLangOptions().CPlusPlus) { 4061 Diag(Loc, diag::err_typecheck_pointer_arith_function_type) 4062 << rex->getType() << rex->getSourceRange(); 4063 return QualType(); 4064 } 4065 4066 // GNU extension: arithmetic on pointer to function 4067 if (!ComplainAboutFunc) 4068 ComplainAboutFunc = rex; 4069 } else if (!rpointee->isDependentType() && 4070 RequireCompleteType(Loc, rpointee, 4071 diag::err_typecheck_sub_ptr_object, 4072 rex->getSourceRange(), 4073 SourceRange(), 4074 rex->getType())) 4075 return QualType(); 4076 4077 if (getLangOptions().CPlusPlus) { 4078 // Pointee types must be the same: C++ [expr.add] 4079 if (!Context.hasSameUnqualifiedType(lpointee, rpointee)) { 4080 Diag(Loc, diag::err_typecheck_sub_ptr_compatible) 4081 << lex->getType() << rex->getType() 4082 << lex->getSourceRange() << rex->getSourceRange(); 4083 return QualType(); 4084 } 4085 } else { 4086 // Pointee types must be compatible C99 6.5.6p3 4087 if (!Context.typesAreCompatible( 4088 Context.getCanonicalType(lpointee).getUnqualifiedType(), 4089 Context.getCanonicalType(rpointee).getUnqualifiedType())) { 4090 Diag(Loc, diag::err_typecheck_sub_ptr_compatible) 4091 << lex->getType() << rex->getType() 4092 << lex->getSourceRange() << rex->getSourceRange(); 4093 return QualType(); 4094 } 4095 } 4096 4097 if (ComplainAboutVoid) 4098 Diag(Loc, diag::ext_gnu_void_ptr) 4099 << lex->getSourceRange() << rex->getSourceRange(); 4100 if (ComplainAboutFunc) 4101 Diag(Loc, diag::ext_gnu_ptr_func_arith) 4102 << ComplainAboutFunc->getType() 4103 << ComplainAboutFunc->getSourceRange(); 4104 4105 if (CompLHSTy) *CompLHSTy = lex->getType(); 4106 return Context.getPointerDiffType(); 4107 } 4108 } 4109 4110 return InvalidOperands(Loc, lex, rex); 4111} 4112 4113// C99 6.5.7 4114QualType Sema::CheckShiftOperands(Expr *&lex, Expr *&rex, SourceLocation Loc, 4115 bool isCompAssign) { 4116 // C99 6.5.7p2: Each of the operands shall have integer type. 4117 if (!lex->getType()->isIntegerType() || !rex->getType()->isIntegerType()) 4118 return InvalidOperands(Loc, lex, rex); 4119 4120 // Shifts don't perform usual arithmetic conversions, they just do integer 4121 // promotions on each operand. C99 6.5.7p3 4122 QualType LHSTy; 4123 if (lex->getType()->isPromotableIntegerType()) 4124 LHSTy = Context.IntTy; 4125 else { 4126 LHSTy = isPromotableBitField(lex, Context); 4127 if (LHSTy.isNull()) 4128 LHSTy = lex->getType(); 4129 } 4130 if (!isCompAssign) 4131 ImpCastExprToType(lex, LHSTy); 4132 4133 UsualUnaryConversions(rex); 4134 4135 // Sanity-check shift operands 4136 llvm::APSInt Right; 4137 // Check right/shifter operand 4138 if (rex->isIntegerConstantExpr(Right, Context)) { 4139 if (Right.isNegative()) 4140 Diag(Loc, diag::warn_shift_negative) << rex->getSourceRange(); 4141 else { 4142 llvm::APInt LeftBits(Right.getBitWidth(), 4143 Context.getTypeSize(lex->getType())); 4144 if (Right.uge(LeftBits)) 4145 Diag(Loc, diag::warn_shift_gt_typewidth) << rex->getSourceRange(); 4146 } 4147 } 4148 4149 // "The type of the result is that of the promoted left operand." 4150 return LHSTy; 4151} 4152 4153// C99 6.5.8, C++ [expr.rel] 4154QualType Sema::CheckCompareOperands(Expr *&lex, Expr *&rex, SourceLocation Loc, 4155 unsigned OpaqueOpc, bool isRelational) { 4156 BinaryOperator::Opcode Opc = (BinaryOperator::Opcode)OpaqueOpc; 4157 4158 if (lex->getType()->isVectorType() || rex->getType()->isVectorType()) 4159 return CheckVectorCompareOperands(lex, rex, Loc, isRelational); 4160 4161 // C99 6.5.8p3 / C99 6.5.9p4 4162 if (lex->getType()->isArithmeticType() && rex->getType()->isArithmeticType()) 4163 UsualArithmeticConversions(lex, rex); 4164 else { 4165 UsualUnaryConversions(lex); 4166 UsualUnaryConversions(rex); 4167 } 4168 QualType lType = lex->getType(); 4169 QualType rType = rex->getType(); 4170 4171 if (!lType->isFloatingType() 4172 && !(lType->isBlockPointerType() && isRelational)) { 4173 // For non-floating point types, check for self-comparisons of the form 4174 // x == x, x != x, x < x, etc. These always evaluate to a constant, and 4175 // often indicate logic errors in the program. 4176 // NOTE: Don't warn about comparisons of enum constants. These can arise 4177 // from macro expansions, and are usually quite deliberate. 4178 Expr *LHSStripped = lex->IgnoreParens(); 4179 Expr *RHSStripped = rex->IgnoreParens(); 4180 if (DeclRefExpr* DRL = dyn_cast<DeclRefExpr>(LHSStripped)) 4181 if (DeclRefExpr* DRR = dyn_cast<DeclRefExpr>(RHSStripped)) 4182 if (DRL->getDecl() == DRR->getDecl() && 4183 !isa<EnumConstantDecl>(DRL->getDecl())) 4184 Diag(Loc, diag::warn_selfcomparison); 4185 4186 if (isa<CastExpr>(LHSStripped)) 4187 LHSStripped = LHSStripped->IgnoreParenCasts(); 4188 if (isa<CastExpr>(RHSStripped)) 4189 RHSStripped = RHSStripped->IgnoreParenCasts(); 4190 4191 // Warn about comparisons against a string constant (unless the other 4192 // operand is null), the user probably wants strcmp. 4193 Expr *literalString = 0; 4194 Expr *literalStringStripped = 0; 4195 if ((isa<StringLiteral>(LHSStripped) || isa<ObjCEncodeExpr>(LHSStripped)) && 4196 !RHSStripped->isNullPointerConstant(Context)) { 4197 literalString = lex; 4198 literalStringStripped = LHSStripped; 4199 } else if ((isa<StringLiteral>(RHSStripped) || 4200 isa<ObjCEncodeExpr>(RHSStripped)) && 4201 !LHSStripped->isNullPointerConstant(Context)) { 4202 literalString = rex; 4203 literalStringStripped = RHSStripped; 4204 } 4205 4206 if (literalString) { 4207 std::string resultComparison; 4208 switch (Opc) { 4209 case BinaryOperator::LT: resultComparison = ") < 0"; break; 4210 case BinaryOperator::GT: resultComparison = ") > 0"; break; 4211 case BinaryOperator::LE: resultComparison = ") <= 0"; break; 4212 case BinaryOperator::GE: resultComparison = ") >= 0"; break; 4213 case BinaryOperator::EQ: resultComparison = ") == 0"; break; 4214 case BinaryOperator::NE: resultComparison = ") != 0"; break; 4215 default: assert(false && "Invalid comparison operator"); 4216 } 4217 Diag(Loc, diag::warn_stringcompare) 4218 << isa<ObjCEncodeExpr>(literalStringStripped) 4219 << literalString->getSourceRange() 4220 << CodeModificationHint::CreateReplacement(SourceRange(Loc), ", ") 4221 << CodeModificationHint::CreateInsertion(lex->getLocStart(), 4222 "strcmp(") 4223 << CodeModificationHint::CreateInsertion( 4224 PP.getLocForEndOfToken(rex->getLocEnd()), 4225 resultComparison); 4226 } 4227 } 4228 4229 // The result of comparisons is 'bool' in C++, 'int' in C. 4230 QualType ResultTy = getLangOptions().CPlusPlus? Context.BoolTy :Context.IntTy; 4231 4232 if (isRelational) { 4233 if (lType->isRealType() && rType->isRealType()) 4234 return ResultTy; 4235 } else { 4236 // Check for comparisons of floating point operands using != and ==. 4237 if (lType->isFloatingType()) { 4238 assert(rType->isFloatingType()); 4239 CheckFloatComparison(Loc,lex,rex); 4240 } 4241 4242 if (lType->isArithmeticType() && rType->isArithmeticType()) 4243 return ResultTy; 4244 } 4245 4246 bool LHSIsNull = lex->isNullPointerConstant(Context); 4247 bool RHSIsNull = rex->isNullPointerConstant(Context); 4248 4249 // All of the following pointer related warnings are GCC extensions, except 4250 // when handling null pointer constants. One day, we can consider making them 4251 // errors (when -pedantic-errors is enabled). 4252 if (lType->isPointerType() && rType->isPointerType()) { // C99 6.5.8p2 4253 QualType LCanPointeeTy = 4254 Context.getCanonicalType(lType->getAs<PointerType>()->getPointeeType()); 4255 QualType RCanPointeeTy = 4256 Context.getCanonicalType(rType->getAs<PointerType>()->getPointeeType()); 4257 4258 if (isRelational) { 4259 if (lType->isFunctionPointerType() || rType->isFunctionPointerType()) { 4260 Diag(Loc, diag::ext_typecheck_ordered_comparison_of_function_pointers) 4261 << lType << rType << lex->getSourceRange() << rex->getSourceRange(); 4262 } 4263 if (LCanPointeeTy->isVoidType() != RCanPointeeTy->isVoidType()) { 4264 Diag(Loc, diag::ext_typecheck_comparison_of_distinct_pointers) 4265 << lType << rType << lex->getSourceRange() << rex->getSourceRange(); 4266 } 4267 } else { 4268 if (lType->isFunctionPointerType() != rType->isFunctionPointerType()) { 4269 if (!LHSIsNull && !RHSIsNull) 4270 Diag(Loc, diag::ext_typecheck_comparison_of_distinct_pointers) 4271 << lType << rType << lex->getSourceRange() << rex->getSourceRange(); 4272 } 4273 } 4274 4275 // Simple check: if the pointee types are identical, we're done. 4276 if (LCanPointeeTy == RCanPointeeTy) 4277 return ResultTy; 4278 4279 if (getLangOptions().CPlusPlus) { 4280 // C++ [expr.rel]p2: 4281 // [...] Pointer conversions (4.10) and qualification 4282 // conversions (4.4) are performed on pointer operands (or on 4283 // a pointer operand and a null pointer constant) to bring 4284 // them to their composite pointer type. [...] 4285 // 4286 // C++ [expr.eq]p2 uses the same notion for (in)equality 4287 // comparisons of pointers. 4288 QualType T = FindCompositePointerType(lex, rex); 4289 if (T.isNull()) { 4290 Diag(Loc, diag::err_typecheck_comparison_of_distinct_pointers) 4291 << lType << rType << lex->getSourceRange() << rex->getSourceRange(); 4292 return QualType(); 4293 } 4294 4295 ImpCastExprToType(lex, T); 4296 ImpCastExprToType(rex, T); 4297 return ResultTy; 4298 } 4299 4300 if (!LHSIsNull && !RHSIsNull && // C99 6.5.9p2 4301 !LCanPointeeTy->isVoidType() && !RCanPointeeTy->isVoidType() && 4302 !Context.typesAreCompatible(LCanPointeeTy.getUnqualifiedType(), 4303 RCanPointeeTy.getUnqualifiedType())) { 4304 Diag(Loc, diag::ext_typecheck_comparison_of_distinct_pointers) 4305 << lType << rType << lex->getSourceRange() << rex->getSourceRange(); 4306 } 4307 ImpCastExprToType(rex, lType); // promote the pointer to pointer 4308 return ResultTy; 4309 } 4310 // C++ allows comparison of pointers with null pointer constants. 4311 if (getLangOptions().CPlusPlus) { 4312 if (lType->isPointerType() && RHSIsNull) { 4313 ImpCastExprToType(rex, lType); 4314 return ResultTy; 4315 } 4316 if (rType->isPointerType() && LHSIsNull) { 4317 ImpCastExprToType(lex, rType); 4318 return ResultTy; 4319 } 4320 // And comparison of nullptr_t with itself. 4321 if (lType->isNullPtrType() && rType->isNullPtrType()) 4322 return ResultTy; 4323 } 4324 // Handle block pointer types. 4325 if (!isRelational && lType->isBlockPointerType() && rType->isBlockPointerType()) { 4326 QualType lpointee = lType->getAs<BlockPointerType>()->getPointeeType(); 4327 QualType rpointee = rType->getAs<BlockPointerType>()->getPointeeType(); 4328 4329 if (!LHSIsNull && !RHSIsNull && 4330 !Context.typesAreCompatible(lpointee, rpointee)) { 4331 Diag(Loc, diag::err_typecheck_comparison_of_distinct_blocks) 4332 << lType << rType << lex->getSourceRange() << rex->getSourceRange(); 4333 } 4334 ImpCastExprToType(rex, lType); // promote the pointer to pointer 4335 return ResultTy; 4336 } 4337 // Allow block pointers to be compared with null pointer constants. 4338 if (!isRelational 4339 && ((lType->isBlockPointerType() && rType->isPointerType()) 4340 || (lType->isPointerType() && rType->isBlockPointerType()))) { 4341 if (!LHSIsNull && !RHSIsNull) { 4342 if (!((rType->isPointerType() && rType->getAs<PointerType>() 4343 ->getPointeeType()->isVoidType()) 4344 || (lType->isPointerType() && lType->getAs<PointerType>() 4345 ->getPointeeType()->isVoidType()))) 4346 Diag(Loc, diag::err_typecheck_comparison_of_distinct_blocks) 4347 << lType << rType << lex->getSourceRange() << rex->getSourceRange(); 4348 } 4349 ImpCastExprToType(rex, lType); // promote the pointer to pointer 4350 return ResultTy; 4351 } 4352 4353 if ((lType->isObjCObjectPointerType() || rType->isObjCObjectPointerType())) { 4354 if (lType->isPointerType() || rType->isPointerType()) { 4355 const PointerType *LPT = lType->getAs<PointerType>(); 4356 const PointerType *RPT = rType->getAs<PointerType>(); 4357 bool LPtrToVoid = LPT ? 4358 Context.getCanonicalType(LPT->getPointeeType())->isVoidType() : false; 4359 bool RPtrToVoid = RPT ? 4360 Context.getCanonicalType(RPT->getPointeeType())->isVoidType() : false; 4361 4362 if (!LPtrToVoid && !RPtrToVoid && 4363 !Context.typesAreCompatible(lType, rType)) { 4364 Diag(Loc, diag::ext_typecheck_comparison_of_distinct_pointers) 4365 << lType << rType << lex->getSourceRange() << rex->getSourceRange(); 4366 } 4367 ImpCastExprToType(rex, lType); 4368 return ResultTy; 4369 } 4370 if (lType->isObjCObjectPointerType() && rType->isObjCObjectPointerType()) { 4371 if (!Context.areComparableObjCPointerTypes(lType, rType)) { 4372 Diag(Loc, diag::ext_typecheck_comparison_of_distinct_pointers) 4373 << lType << rType << lex->getSourceRange() << rex->getSourceRange(); 4374 } 4375 ImpCastExprToType(rex, lType); 4376 return ResultTy; 4377 } 4378 } 4379 if (lType->isAnyPointerType() && rType->isIntegerType()) { 4380 if (isRelational) 4381 Diag(Loc, diag::ext_typecheck_ordered_comparison_of_pointer_integer) 4382 << lType << rType << lex->getSourceRange() << rex->getSourceRange(); 4383 else if (!RHSIsNull) 4384 Diag(Loc, diag::ext_typecheck_comparison_of_pointer_integer) 4385 << lType << rType << lex->getSourceRange() << rex->getSourceRange(); 4386 ImpCastExprToType(rex, lType); // promote the integer to pointer 4387 return ResultTy; 4388 } 4389 if (lType->isIntegerType() && rType->isAnyPointerType()) { 4390 if (isRelational) 4391 Diag(Loc, diag::ext_typecheck_ordered_comparison_of_pointer_integer) 4392 << lType << rType << lex->getSourceRange() << rex->getSourceRange(); 4393 else if (!LHSIsNull) 4394 Diag(Loc, diag::ext_typecheck_comparison_of_pointer_integer) 4395 << lType << rType << lex->getSourceRange() << rex->getSourceRange(); 4396 ImpCastExprToType(lex, rType); // promote the integer to pointer 4397 return ResultTy; 4398 } 4399 // Handle block pointers. 4400 if (!isRelational && RHSIsNull 4401 && lType->isBlockPointerType() && rType->isIntegerType()) { 4402 ImpCastExprToType(rex, lType); // promote the integer to pointer 4403 return ResultTy; 4404 } 4405 if (!isRelational && LHSIsNull 4406 && lType->isIntegerType() && rType->isBlockPointerType()) { 4407 ImpCastExprToType(lex, rType); // promote the integer to pointer 4408 return ResultTy; 4409 } 4410 return InvalidOperands(Loc, lex, rex); 4411} 4412 4413/// CheckVectorCompareOperands - vector comparisons are a clang extension that 4414/// operates on extended vector types. Instead of producing an IntTy result, 4415/// like a scalar comparison, a vector comparison produces a vector of integer 4416/// types. 4417QualType Sema::CheckVectorCompareOperands(Expr *&lex, Expr *&rex, 4418 SourceLocation Loc, 4419 bool isRelational) { 4420 // Check to make sure we're operating on vectors of the same type and width, 4421 // Allowing one side to be a scalar of element type. 4422 QualType vType = CheckVectorOperands(Loc, lex, rex); 4423 if (vType.isNull()) 4424 return vType; 4425 4426 QualType lType = lex->getType(); 4427 QualType rType = rex->getType(); 4428 4429 // For non-floating point types, check for self-comparisons of the form 4430 // x == x, x != x, x < x, etc. These always evaluate to a constant, and 4431 // often indicate logic errors in the program. 4432 if (!lType->isFloatingType()) { 4433 if (DeclRefExpr* DRL = dyn_cast<DeclRefExpr>(lex->IgnoreParens())) 4434 if (DeclRefExpr* DRR = dyn_cast<DeclRefExpr>(rex->IgnoreParens())) 4435 if (DRL->getDecl() == DRR->getDecl()) 4436 Diag(Loc, diag::warn_selfcomparison); 4437 } 4438 4439 // Check for comparisons of floating point operands using != and ==. 4440 if (!isRelational && lType->isFloatingType()) { 4441 assert (rType->isFloatingType()); 4442 CheckFloatComparison(Loc,lex,rex); 4443 } 4444 4445 // Return the type for the comparison, which is the same as vector type for 4446 // integer vectors, or an integer type of identical size and number of 4447 // elements for floating point vectors. 4448 if (lType->isIntegerType()) 4449 return lType; 4450 4451 const VectorType *VTy = lType->getAsVectorType(); 4452 unsigned TypeSize = Context.getTypeSize(VTy->getElementType()); 4453 if (TypeSize == Context.getTypeSize(Context.IntTy)) 4454 return Context.getExtVectorType(Context.IntTy, VTy->getNumElements()); 4455 if (TypeSize == Context.getTypeSize(Context.LongTy)) 4456 return Context.getExtVectorType(Context.LongTy, VTy->getNumElements()); 4457 4458 assert(TypeSize == Context.getTypeSize(Context.LongLongTy) && 4459 "Unhandled vector element size in vector compare"); 4460 return Context.getExtVectorType(Context.LongLongTy, VTy->getNumElements()); 4461} 4462 4463inline QualType Sema::CheckBitwiseOperands( 4464 Expr *&lex, Expr *&rex, SourceLocation Loc, bool isCompAssign) 4465{ 4466 if (lex->getType()->isVectorType() || rex->getType()->isVectorType()) 4467 return CheckVectorOperands(Loc, lex, rex); 4468 4469 QualType compType = UsualArithmeticConversions(lex, rex, isCompAssign); 4470 4471 if (lex->getType()->isIntegerType() && rex->getType()->isIntegerType()) 4472 return compType; 4473 return InvalidOperands(Loc, lex, rex); 4474} 4475 4476inline QualType Sema::CheckLogicalOperands( // C99 6.5.[13,14] 4477 Expr *&lex, Expr *&rex, SourceLocation Loc) 4478{ 4479 UsualUnaryConversions(lex); 4480 UsualUnaryConversions(rex); 4481 4482 if (lex->getType()->isScalarType() && rex->getType()->isScalarType()) 4483 return Context.IntTy; 4484 return InvalidOperands(Loc, lex, rex); 4485} 4486 4487/// IsReadonlyProperty - Verify that otherwise a valid l-value expression 4488/// is a read-only property; return true if so. A readonly property expression 4489/// depends on various declarations and thus must be treated specially. 4490/// 4491static bool IsReadonlyProperty(Expr *E, Sema &S) 4492{ 4493 if (E->getStmtClass() == Expr::ObjCPropertyRefExprClass) { 4494 const ObjCPropertyRefExpr* PropExpr = cast<ObjCPropertyRefExpr>(E); 4495 if (ObjCPropertyDecl *PDecl = PropExpr->getProperty()) { 4496 QualType BaseType = PropExpr->getBase()->getType(); 4497 if (const ObjCObjectPointerType *OPT = 4498 BaseType->getAsObjCInterfacePointerType()) 4499 if (ObjCInterfaceDecl *IFace = OPT->getInterfaceDecl()) 4500 if (S.isPropertyReadonly(PDecl, IFace)) 4501 return true; 4502 } 4503 } 4504 return false; 4505} 4506 4507/// CheckForModifiableLvalue - Verify that E is a modifiable lvalue. If not, 4508/// emit an error and return true. If so, return false. 4509static bool CheckForModifiableLvalue(Expr *E, SourceLocation Loc, Sema &S) { 4510 SourceLocation OrigLoc = Loc; 4511 Expr::isModifiableLvalueResult IsLV = E->isModifiableLvalue(S.Context, 4512 &Loc); 4513 if (IsLV == Expr::MLV_Valid && IsReadonlyProperty(E, S)) 4514 IsLV = Expr::MLV_ReadonlyProperty; 4515 if (IsLV == Expr::MLV_Valid) 4516 return false; 4517 4518 unsigned Diag = 0; 4519 bool NeedType = false; 4520 switch (IsLV) { // C99 6.5.16p2 4521 default: assert(0 && "Unknown result from isModifiableLvalue!"); 4522 case Expr::MLV_ConstQualified: Diag = diag::err_typecheck_assign_const; break; 4523 case Expr::MLV_ArrayType: 4524 Diag = diag::err_typecheck_array_not_modifiable_lvalue; 4525 NeedType = true; 4526 break; 4527 case Expr::MLV_NotObjectType: 4528 Diag = diag::err_typecheck_non_object_not_modifiable_lvalue; 4529 NeedType = true; 4530 break; 4531 case Expr::MLV_LValueCast: 4532 Diag = diag::err_typecheck_lvalue_casts_not_supported; 4533 break; 4534 case Expr::MLV_InvalidExpression: 4535 Diag = diag::err_typecheck_expression_not_modifiable_lvalue; 4536 break; 4537 case Expr::MLV_IncompleteType: 4538 case Expr::MLV_IncompleteVoidType: 4539 return S.RequireCompleteType(Loc, E->getType(), 4540 diag::err_typecheck_incomplete_type_not_modifiable_lvalue, 4541 E->getSourceRange()); 4542 case Expr::MLV_DuplicateVectorComponents: 4543 Diag = diag::err_typecheck_duplicate_vector_components_not_mlvalue; 4544 break; 4545 case Expr::MLV_NotBlockQualified: 4546 Diag = diag::err_block_decl_ref_not_modifiable_lvalue; 4547 break; 4548 case Expr::MLV_ReadonlyProperty: 4549 Diag = diag::error_readonly_property_assignment; 4550 break; 4551 case Expr::MLV_NoSetterProperty: 4552 Diag = diag::error_nosetter_property_assignment; 4553 break; 4554 } 4555 4556 SourceRange Assign; 4557 if (Loc != OrigLoc) 4558 Assign = SourceRange(OrigLoc, OrigLoc); 4559 if (NeedType) 4560 S.Diag(Loc, Diag) << E->getType() << E->getSourceRange() << Assign; 4561 else 4562 S.Diag(Loc, Diag) << E->getSourceRange() << Assign; 4563 return true; 4564} 4565 4566 4567 4568// C99 6.5.16.1 4569QualType Sema::CheckAssignmentOperands(Expr *LHS, Expr *&RHS, 4570 SourceLocation Loc, 4571 QualType CompoundType) { 4572 // Verify that LHS is a modifiable lvalue, and emit error if not. 4573 if (CheckForModifiableLvalue(LHS, Loc, *this)) 4574 return QualType(); 4575 4576 QualType LHSType = LHS->getType(); 4577 QualType RHSType = CompoundType.isNull() ? RHS->getType() : CompoundType; 4578 4579 AssignConvertType ConvTy; 4580 if (CompoundType.isNull()) { 4581 // Simple assignment "x = y". 4582 ConvTy = CheckSingleAssignmentConstraints(LHSType, RHS); 4583 // Special case of NSObject attributes on c-style pointer types. 4584 if (ConvTy == IncompatiblePointer && 4585 ((Context.isObjCNSObjectType(LHSType) && 4586 RHSType->isObjCObjectPointerType()) || 4587 (Context.isObjCNSObjectType(RHSType) && 4588 LHSType->isObjCObjectPointerType()))) 4589 ConvTy = Compatible; 4590 4591 // If the RHS is a unary plus or minus, check to see if they = and + are 4592 // right next to each other. If so, the user may have typo'd "x =+ 4" 4593 // instead of "x += 4". 4594 Expr *RHSCheck = RHS; 4595 if (ImplicitCastExpr *ICE = dyn_cast<ImplicitCastExpr>(RHSCheck)) 4596 RHSCheck = ICE->getSubExpr(); 4597 if (UnaryOperator *UO = dyn_cast<UnaryOperator>(RHSCheck)) { 4598 if ((UO->getOpcode() == UnaryOperator::Plus || 4599 UO->getOpcode() == UnaryOperator::Minus) && 4600 Loc.isFileID() && UO->getOperatorLoc().isFileID() && 4601 // Only if the two operators are exactly adjacent. 4602 Loc.getFileLocWithOffset(1) == UO->getOperatorLoc() && 4603 // And there is a space or other character before the subexpr of the 4604 // unary +/-. We don't want to warn on "x=-1". 4605 Loc.getFileLocWithOffset(2) != UO->getSubExpr()->getLocStart() && 4606 UO->getSubExpr()->getLocStart().isFileID()) { 4607 Diag(Loc, diag::warn_not_compound_assign) 4608 << (UO->getOpcode() == UnaryOperator::Plus ? "+" : "-") 4609 << SourceRange(UO->getOperatorLoc(), UO->getOperatorLoc()); 4610 } 4611 } 4612 } else { 4613 // Compound assignment "x += y" 4614 ConvTy = CheckAssignmentConstraints(LHSType, RHSType); 4615 } 4616 4617 if (DiagnoseAssignmentResult(ConvTy, Loc, LHSType, RHSType, 4618 RHS, "assigning")) 4619 return QualType(); 4620 4621 // C99 6.5.16p3: The type of an assignment expression is the type of the 4622 // left operand unless the left operand has qualified type, in which case 4623 // it is the unqualified version of the type of the left operand. 4624 // C99 6.5.16.1p2: In simple assignment, the value of the right operand 4625 // is converted to the type of the assignment expression (above). 4626 // C++ 5.17p1: the type of the assignment expression is that of its left 4627 // operand. 4628 return LHSType.getUnqualifiedType(); 4629} 4630 4631// C99 6.5.17 4632QualType Sema::CheckCommaOperands(Expr *LHS, Expr *&RHS, SourceLocation Loc) { 4633 // Comma performs lvalue conversion (C99 6.3.2.1), but not unary conversions. 4634 DefaultFunctionArrayConversion(RHS); 4635 4636 // FIXME: Check that RHS type is complete in C mode (it's legal for it to be 4637 // incomplete in C++). 4638 4639 return RHS->getType(); 4640} 4641 4642/// CheckIncrementDecrementOperand - unlike most "Check" methods, this routine 4643/// doesn't need to call UsualUnaryConversions or UsualArithmeticConversions. 4644QualType Sema::CheckIncrementDecrementOperand(Expr *Op, SourceLocation OpLoc, 4645 bool isInc) { 4646 if (Op->isTypeDependent()) 4647 return Context.DependentTy; 4648 4649 QualType ResType = Op->getType(); 4650 assert(!ResType.isNull() && "no type for increment/decrement expression"); 4651 4652 if (getLangOptions().CPlusPlus && ResType->isBooleanType()) { 4653 // Decrement of bool is not allowed. 4654 if (!isInc) { 4655 Diag(OpLoc, diag::err_decrement_bool) << Op->getSourceRange(); 4656 return QualType(); 4657 } 4658 // Increment of bool sets it to true, but is deprecated. 4659 Diag(OpLoc, diag::warn_increment_bool) << Op->getSourceRange(); 4660 } else if (ResType->isRealType()) { 4661 // OK! 4662 } else if (ResType->isAnyPointerType()) { 4663 QualType PointeeTy = ResType->getPointeeType(); 4664 4665 // C99 6.5.2.4p2, 6.5.6p2 4666 if (PointeeTy->isVoidType()) { 4667 if (getLangOptions().CPlusPlus) { 4668 Diag(OpLoc, diag::err_typecheck_pointer_arith_void_type) 4669 << Op->getSourceRange(); 4670 return QualType(); 4671 } 4672 4673 // Pointer to void is a GNU extension in C. 4674 Diag(OpLoc, diag::ext_gnu_void_ptr) << Op->getSourceRange(); 4675 } else if (PointeeTy->isFunctionType()) { 4676 if (getLangOptions().CPlusPlus) { 4677 Diag(OpLoc, diag::err_typecheck_pointer_arith_function_type) 4678 << Op->getType() << Op->getSourceRange(); 4679 return QualType(); 4680 } 4681 4682 Diag(OpLoc, diag::ext_gnu_ptr_func_arith) 4683 << ResType << Op->getSourceRange(); 4684 } else if (RequireCompleteType(OpLoc, PointeeTy, 4685 diag::err_typecheck_arithmetic_incomplete_type, 4686 Op->getSourceRange(), SourceRange(), 4687 ResType)) 4688 return QualType(); 4689 // Diagnose bad cases where we step over interface counts. 4690 else if (PointeeTy->isObjCInterfaceType() && LangOpts.ObjCNonFragileABI) { 4691 Diag(OpLoc, diag::err_arithmetic_nonfragile_interface) 4692 << PointeeTy << Op->getSourceRange(); 4693 return QualType(); 4694 } 4695 } else if (ResType->isComplexType()) { 4696 // C99 does not support ++/-- on complex types, we allow as an extension. 4697 Diag(OpLoc, diag::ext_integer_increment_complex) 4698 << ResType << Op->getSourceRange(); 4699 } else { 4700 Diag(OpLoc, diag::err_typecheck_illegal_increment_decrement) 4701 << ResType << Op->getSourceRange(); 4702 return QualType(); 4703 } 4704 // At this point, we know we have a real, complex or pointer type. 4705 // Now make sure the operand is a modifiable lvalue. 4706 if (CheckForModifiableLvalue(Op, OpLoc, *this)) 4707 return QualType(); 4708 return ResType; 4709} 4710 4711/// getPrimaryDecl - Helper function for CheckAddressOfOperand(). 4712/// This routine allows us to typecheck complex/recursive expressions 4713/// where the declaration is needed for type checking. We only need to 4714/// handle cases when the expression references a function designator 4715/// or is an lvalue. Here are some examples: 4716/// - &(x) => x 4717/// - &*****f => f for f a function designator. 4718/// - &s.xx => s 4719/// - &s.zz[1].yy -> s, if zz is an array 4720/// - *(x + 1) -> x, if x is an array 4721/// - &"123"[2] -> 0 4722/// - & __real__ x -> x 4723static NamedDecl *getPrimaryDecl(Expr *E) { 4724 switch (E->getStmtClass()) { 4725 case Stmt::DeclRefExprClass: 4726 case Stmt::QualifiedDeclRefExprClass: 4727 return cast<DeclRefExpr>(E)->getDecl(); 4728 case Stmt::MemberExprClass: 4729 // If this is an arrow operator, the address is an offset from 4730 // the base's value, so the object the base refers to is 4731 // irrelevant. 4732 if (cast<MemberExpr>(E)->isArrow()) 4733 return 0; 4734 // Otherwise, the expression refers to a part of the base 4735 return getPrimaryDecl(cast<MemberExpr>(E)->getBase()); 4736 case Stmt::ArraySubscriptExprClass: { 4737 // FIXME: This code shouldn't be necessary! We should catch the implicit 4738 // promotion of register arrays earlier. 4739 Expr* Base = cast<ArraySubscriptExpr>(E)->getBase(); 4740 if (ImplicitCastExpr* ICE = dyn_cast<ImplicitCastExpr>(Base)) { 4741 if (ICE->getSubExpr()->getType()->isArrayType()) 4742 return getPrimaryDecl(ICE->getSubExpr()); 4743 } 4744 return 0; 4745 } 4746 case Stmt::UnaryOperatorClass: { 4747 UnaryOperator *UO = cast<UnaryOperator>(E); 4748 4749 switch(UO->getOpcode()) { 4750 case UnaryOperator::Real: 4751 case UnaryOperator::Imag: 4752 case UnaryOperator::Extension: 4753 return getPrimaryDecl(UO->getSubExpr()); 4754 default: 4755 return 0; 4756 } 4757 } 4758 case Stmt::ParenExprClass: 4759 return getPrimaryDecl(cast<ParenExpr>(E)->getSubExpr()); 4760 case Stmt::ImplicitCastExprClass: 4761 // If the result of an implicit cast is an l-value, we care about 4762 // the sub-expression; otherwise, the result here doesn't matter. 4763 return getPrimaryDecl(cast<ImplicitCastExpr>(E)->getSubExpr()); 4764 default: 4765 return 0; 4766 } 4767} 4768 4769/// CheckAddressOfOperand - The operand of & must be either a function 4770/// designator or an lvalue designating an object. If it is an lvalue, the 4771/// object cannot be declared with storage class register or be a bit field. 4772/// Note: The usual conversions are *not* applied to the operand of the & 4773/// operator (C99 6.3.2.1p[2-4]), and its result is never an lvalue. 4774/// In C++, the operand might be an overloaded function name, in which case 4775/// we allow the '&' but retain the overloaded-function type. 4776QualType Sema::CheckAddressOfOperand(Expr *op, SourceLocation OpLoc) { 4777 // Make sure to ignore parentheses in subsequent checks 4778 op = op->IgnoreParens(); 4779 4780 if (op->isTypeDependent()) 4781 return Context.DependentTy; 4782 4783 if (getLangOptions().C99) { 4784 // Implement C99-only parts of addressof rules. 4785 if (UnaryOperator* uOp = dyn_cast<UnaryOperator>(op)) { 4786 if (uOp->getOpcode() == UnaryOperator::Deref) 4787 // Per C99 6.5.3.2, the address of a deref always returns a valid result 4788 // (assuming the deref expression is valid). 4789 return uOp->getSubExpr()->getType(); 4790 } 4791 // Technically, there should be a check for array subscript 4792 // expressions here, but the result of one is always an lvalue anyway. 4793 } 4794 NamedDecl *dcl = getPrimaryDecl(op); 4795 Expr::isLvalueResult lval = op->isLvalue(Context); 4796 4797 if (lval != Expr::LV_Valid && lval != Expr::LV_IncompleteVoidType) { 4798 // C99 6.5.3.2p1 4799 // The operand must be either an l-value or a function designator 4800 if (!op->getType()->isFunctionType()) { 4801 // FIXME: emit more specific diag... 4802 Diag(OpLoc, diag::err_typecheck_invalid_lvalue_addrof) 4803 << op->getSourceRange(); 4804 return QualType(); 4805 } 4806 } else if (op->getBitField()) { // C99 6.5.3.2p1 4807 // The operand cannot be a bit-field 4808 Diag(OpLoc, diag::err_typecheck_address_of) 4809 << "bit-field" << op->getSourceRange(); 4810 return QualType(); 4811 } else if (isa<ExtVectorElementExpr>(op) || (isa<ArraySubscriptExpr>(op) && 4812 cast<ArraySubscriptExpr>(op)->getBase()->getType()->isVectorType())){ 4813 // The operand cannot be an element of a vector 4814 Diag(OpLoc, diag::err_typecheck_address_of) 4815 << "vector element" << op->getSourceRange(); 4816 return QualType(); 4817 } else if (isa<ObjCPropertyRefExpr>(op)) { 4818 // cannot take address of a property expression. 4819 Diag(OpLoc, diag::err_typecheck_address_of) 4820 << "property expression" << op->getSourceRange(); 4821 return QualType(); 4822 } else if (dcl) { // C99 6.5.3.2p1 4823 // We have an lvalue with a decl. Make sure the decl is not declared 4824 // with the register storage-class specifier. 4825 if (const VarDecl *vd = dyn_cast<VarDecl>(dcl)) { 4826 if (vd->getStorageClass() == VarDecl::Register) { 4827 Diag(OpLoc, diag::err_typecheck_address_of) 4828 << "register variable" << op->getSourceRange(); 4829 return QualType(); 4830 } 4831 } else if (isa<OverloadedFunctionDecl>(dcl) || 4832 isa<FunctionTemplateDecl>(dcl)) { 4833 return Context.OverloadTy; 4834 } else if (FieldDecl *FD = dyn_cast<FieldDecl>(dcl)) { 4835 // Okay: we can take the address of a field. 4836 // Could be a pointer to member, though, if there is an explicit 4837 // scope qualifier for the class. 4838 if (isa<QualifiedDeclRefExpr>(op)) { 4839 DeclContext *Ctx = dcl->getDeclContext(); 4840 if (Ctx && Ctx->isRecord()) { 4841 if (FD->getType()->isReferenceType()) { 4842 Diag(OpLoc, 4843 diag::err_cannot_form_pointer_to_member_of_reference_type) 4844 << FD->getDeclName() << FD->getType(); 4845 return QualType(); 4846 } 4847 4848 return Context.getMemberPointerType(op->getType(), 4849 Context.getTypeDeclType(cast<RecordDecl>(Ctx)).getTypePtr()); 4850 } 4851 } 4852 } else if (CXXMethodDecl *MD = dyn_cast<CXXMethodDecl>(dcl)) { 4853 // Okay: we can take the address of a function. 4854 // As above. 4855 if (isa<QualifiedDeclRefExpr>(op) && MD->isInstance()) 4856 return Context.getMemberPointerType(op->getType(), 4857 Context.getTypeDeclType(MD->getParent()).getTypePtr()); 4858 } else if (!isa<FunctionDecl>(dcl)) 4859 assert(0 && "Unknown/unexpected decl type"); 4860 } 4861 4862 if (lval == Expr::LV_IncompleteVoidType) { 4863 // Taking the address of a void variable is technically illegal, but we 4864 // allow it in cases which are otherwise valid. 4865 // Example: "extern void x; void* y = &x;". 4866 Diag(OpLoc, diag::ext_typecheck_addrof_void) << op->getSourceRange(); 4867 } 4868 4869 // If the operand has type "type", the result has type "pointer to type". 4870 return Context.getPointerType(op->getType()); 4871} 4872 4873QualType Sema::CheckIndirectionOperand(Expr *Op, SourceLocation OpLoc) { 4874 if (Op->isTypeDependent()) 4875 return Context.DependentTy; 4876 4877 UsualUnaryConversions(Op); 4878 QualType Ty = Op->getType(); 4879 4880 // Note that per both C89 and C99, this is always legal, even if ptype is an 4881 // incomplete type or void. It would be possible to warn about dereferencing 4882 // a void pointer, but it's completely well-defined, and such a warning is 4883 // unlikely to catch any mistakes. 4884 if (const PointerType *PT = Ty->getAs<PointerType>()) 4885 return PT->getPointeeType(); 4886 4887 if (const ObjCObjectPointerType *OPT = Ty->getAsObjCObjectPointerType()) 4888 return OPT->getPointeeType(); 4889 4890 Diag(OpLoc, diag::err_typecheck_indirection_requires_pointer) 4891 << Ty << Op->getSourceRange(); 4892 return QualType(); 4893} 4894 4895static inline BinaryOperator::Opcode ConvertTokenKindToBinaryOpcode( 4896 tok::TokenKind Kind) { 4897 BinaryOperator::Opcode Opc; 4898 switch (Kind) { 4899 default: assert(0 && "Unknown binop!"); 4900 case tok::periodstar: Opc = BinaryOperator::PtrMemD; break; 4901 case tok::arrowstar: Opc = BinaryOperator::PtrMemI; break; 4902 case tok::star: Opc = BinaryOperator::Mul; break; 4903 case tok::slash: Opc = BinaryOperator::Div; break; 4904 case tok::percent: Opc = BinaryOperator::Rem; break; 4905 case tok::plus: Opc = BinaryOperator::Add; break; 4906 case tok::minus: Opc = BinaryOperator::Sub; break; 4907 case tok::lessless: Opc = BinaryOperator::Shl; break; 4908 case tok::greatergreater: Opc = BinaryOperator::Shr; break; 4909 case tok::lessequal: Opc = BinaryOperator::LE; break; 4910 case tok::less: Opc = BinaryOperator::LT; break; 4911 case tok::greaterequal: Opc = BinaryOperator::GE; break; 4912 case tok::greater: Opc = BinaryOperator::GT; break; 4913 case tok::exclaimequal: Opc = BinaryOperator::NE; break; 4914 case tok::equalequal: Opc = BinaryOperator::EQ; break; 4915 case tok::amp: Opc = BinaryOperator::And; break; 4916 case tok::caret: Opc = BinaryOperator::Xor; break; 4917 case tok::pipe: Opc = BinaryOperator::Or; break; 4918 case tok::ampamp: Opc = BinaryOperator::LAnd; break; 4919 case tok::pipepipe: Opc = BinaryOperator::LOr; break; 4920 case tok::equal: Opc = BinaryOperator::Assign; break; 4921 case tok::starequal: Opc = BinaryOperator::MulAssign; break; 4922 case tok::slashequal: Opc = BinaryOperator::DivAssign; break; 4923 case tok::percentequal: Opc = BinaryOperator::RemAssign; break; 4924 case tok::plusequal: Opc = BinaryOperator::AddAssign; break; 4925 case tok::minusequal: Opc = BinaryOperator::SubAssign; break; 4926 case tok::lesslessequal: Opc = BinaryOperator::ShlAssign; break; 4927 case tok::greatergreaterequal: Opc = BinaryOperator::ShrAssign; break; 4928 case tok::ampequal: Opc = BinaryOperator::AndAssign; break; 4929 case tok::caretequal: Opc = BinaryOperator::XorAssign; break; 4930 case tok::pipeequal: Opc = BinaryOperator::OrAssign; break; 4931 case tok::comma: Opc = BinaryOperator::Comma; break; 4932 } 4933 return Opc; 4934} 4935 4936static inline UnaryOperator::Opcode ConvertTokenKindToUnaryOpcode( 4937 tok::TokenKind Kind) { 4938 UnaryOperator::Opcode Opc; 4939 switch (Kind) { 4940 default: assert(0 && "Unknown unary op!"); 4941 case tok::plusplus: Opc = UnaryOperator::PreInc; break; 4942 case tok::minusminus: Opc = UnaryOperator::PreDec; break; 4943 case tok::amp: Opc = UnaryOperator::AddrOf; break; 4944 case tok::star: Opc = UnaryOperator::Deref; break; 4945 case tok::plus: Opc = UnaryOperator::Plus; break; 4946 case tok::minus: Opc = UnaryOperator::Minus; break; 4947 case tok::tilde: Opc = UnaryOperator::Not; break; 4948 case tok::exclaim: Opc = UnaryOperator::LNot; break; 4949 case tok::kw___real: Opc = UnaryOperator::Real; break; 4950 case tok::kw___imag: Opc = UnaryOperator::Imag; break; 4951 case tok::kw___extension__: Opc = UnaryOperator::Extension; break; 4952 } 4953 return Opc; 4954} 4955 4956/// CreateBuiltinBinOp - Creates a new built-in binary operation with 4957/// operator @p Opc at location @c TokLoc. This routine only supports 4958/// built-in operations; ActOnBinOp handles overloaded operators. 4959Action::OwningExprResult Sema::CreateBuiltinBinOp(SourceLocation OpLoc, 4960 unsigned Op, 4961 Expr *lhs, Expr *rhs) { 4962 QualType ResultTy; // Result type of the binary operator. 4963 BinaryOperator::Opcode Opc = (BinaryOperator::Opcode)Op; 4964 // The following two variables are used for compound assignment operators 4965 QualType CompLHSTy; // Type of LHS after promotions for computation 4966 QualType CompResultTy; // Type of computation result 4967 4968 switch (Opc) { 4969 case BinaryOperator::Assign: 4970 ResultTy = CheckAssignmentOperands(lhs, rhs, OpLoc, QualType()); 4971 break; 4972 case BinaryOperator::PtrMemD: 4973 case BinaryOperator::PtrMemI: 4974 ResultTy = CheckPointerToMemberOperands(lhs, rhs, OpLoc, 4975 Opc == BinaryOperator::PtrMemI); 4976 break; 4977 case BinaryOperator::Mul: 4978 case BinaryOperator::Div: 4979 ResultTy = CheckMultiplyDivideOperands(lhs, rhs, OpLoc); 4980 break; 4981 case BinaryOperator::Rem: 4982 ResultTy = CheckRemainderOperands(lhs, rhs, OpLoc); 4983 break; 4984 case BinaryOperator::Add: 4985 ResultTy = CheckAdditionOperands(lhs, rhs, OpLoc); 4986 break; 4987 case BinaryOperator::Sub: 4988 ResultTy = CheckSubtractionOperands(lhs, rhs, OpLoc); 4989 break; 4990 case BinaryOperator::Shl: 4991 case BinaryOperator::Shr: 4992 ResultTy = CheckShiftOperands(lhs, rhs, OpLoc); 4993 break; 4994 case BinaryOperator::LE: 4995 case BinaryOperator::LT: 4996 case BinaryOperator::GE: 4997 case BinaryOperator::GT: 4998 ResultTy = CheckCompareOperands(lhs, rhs, OpLoc, Opc, true); 4999 break; 5000 case BinaryOperator::EQ: 5001 case BinaryOperator::NE: 5002 ResultTy = CheckCompareOperands(lhs, rhs, OpLoc, Opc, false); 5003 break; 5004 case BinaryOperator::And: 5005 case BinaryOperator::Xor: 5006 case BinaryOperator::Or: 5007 ResultTy = CheckBitwiseOperands(lhs, rhs, OpLoc); 5008 break; 5009 case BinaryOperator::LAnd: 5010 case BinaryOperator::LOr: 5011 ResultTy = CheckLogicalOperands(lhs, rhs, OpLoc); 5012 break; 5013 case BinaryOperator::MulAssign: 5014 case BinaryOperator::DivAssign: 5015 CompResultTy = CheckMultiplyDivideOperands(lhs, rhs, OpLoc, true); 5016 CompLHSTy = CompResultTy; 5017 if (!CompResultTy.isNull()) 5018 ResultTy = CheckAssignmentOperands(lhs, rhs, OpLoc, CompResultTy); 5019 break; 5020 case BinaryOperator::RemAssign: 5021 CompResultTy = CheckRemainderOperands(lhs, rhs, OpLoc, true); 5022 CompLHSTy = CompResultTy; 5023 if (!CompResultTy.isNull()) 5024 ResultTy = CheckAssignmentOperands(lhs, rhs, OpLoc, CompResultTy); 5025 break; 5026 case BinaryOperator::AddAssign: 5027 CompResultTy = CheckAdditionOperands(lhs, rhs, OpLoc, &CompLHSTy); 5028 if (!CompResultTy.isNull()) 5029 ResultTy = CheckAssignmentOperands(lhs, rhs, OpLoc, CompResultTy); 5030 break; 5031 case BinaryOperator::SubAssign: 5032 CompResultTy = CheckSubtractionOperands(lhs, rhs, OpLoc, &CompLHSTy); 5033 if (!CompResultTy.isNull()) 5034 ResultTy = CheckAssignmentOperands(lhs, rhs, OpLoc, CompResultTy); 5035 break; 5036 case BinaryOperator::ShlAssign: 5037 case BinaryOperator::ShrAssign: 5038 CompResultTy = CheckShiftOperands(lhs, rhs, OpLoc, true); 5039 CompLHSTy = CompResultTy; 5040 if (!CompResultTy.isNull()) 5041 ResultTy = CheckAssignmentOperands(lhs, rhs, OpLoc, CompResultTy); 5042 break; 5043 case BinaryOperator::AndAssign: 5044 case BinaryOperator::XorAssign: 5045 case BinaryOperator::OrAssign: 5046 CompResultTy = CheckBitwiseOperands(lhs, rhs, OpLoc, true); 5047 CompLHSTy = CompResultTy; 5048 if (!CompResultTy.isNull()) 5049 ResultTy = CheckAssignmentOperands(lhs, rhs, OpLoc, CompResultTy); 5050 break; 5051 case BinaryOperator::Comma: 5052 ResultTy = CheckCommaOperands(lhs, rhs, OpLoc); 5053 break; 5054 } 5055 if (ResultTy.isNull()) 5056 return ExprError(); 5057 if (CompResultTy.isNull()) 5058 return Owned(new (Context) BinaryOperator(lhs, rhs, Opc, ResultTy, OpLoc)); 5059 else 5060 return Owned(new (Context) CompoundAssignOperator(lhs, rhs, Opc, ResultTy, 5061 CompLHSTy, CompResultTy, 5062 OpLoc)); 5063} 5064 5065// Binary Operators. 'Tok' is the token for the operator. 5066Action::OwningExprResult Sema::ActOnBinOp(Scope *S, SourceLocation TokLoc, 5067 tok::TokenKind Kind, 5068 ExprArg LHS, ExprArg RHS) { 5069 BinaryOperator::Opcode Opc = ConvertTokenKindToBinaryOpcode(Kind); 5070 Expr *lhs = LHS.takeAs<Expr>(), *rhs = RHS.takeAs<Expr>(); 5071 5072 assert((lhs != 0) && "ActOnBinOp(): missing left expression"); 5073 assert((rhs != 0) && "ActOnBinOp(): missing right expression"); 5074 5075 if (getLangOptions().CPlusPlus && 5076 (lhs->getType()->isOverloadableType() || 5077 rhs->getType()->isOverloadableType())) { 5078 // Find all of the overloaded operators visible from this 5079 // point. We perform both an operator-name lookup from the local 5080 // scope and an argument-dependent lookup based on the types of 5081 // the arguments. 5082 FunctionSet Functions; 5083 OverloadedOperatorKind OverOp = BinaryOperator::getOverloadedOperator(Opc); 5084 if (OverOp != OO_None) { 5085 LookupOverloadedOperatorName(OverOp, S, lhs->getType(), rhs->getType(), 5086 Functions); 5087 Expr *Args[2] = { lhs, rhs }; 5088 DeclarationName OpName 5089 = Context.DeclarationNames.getCXXOperatorName(OverOp); 5090 ArgumentDependentLookup(OpName, Args, 2, Functions); 5091 } 5092 5093 // Build the (potentially-overloaded, potentially-dependent) 5094 // binary operation. 5095 return CreateOverloadedBinOp(TokLoc, Opc, Functions, lhs, rhs); 5096 } 5097 5098 // Build a built-in binary operation. 5099 return CreateBuiltinBinOp(TokLoc, Opc, lhs, rhs); 5100} 5101 5102Action::OwningExprResult Sema::CreateBuiltinUnaryOp(SourceLocation OpLoc, 5103 unsigned OpcIn, 5104 ExprArg InputArg) { 5105 UnaryOperator::Opcode Opc = static_cast<UnaryOperator::Opcode>(OpcIn); 5106 5107 // FIXME: Input is modified below, but InputArg is not updated appropriately. 5108 Expr *Input = (Expr *)InputArg.get(); 5109 QualType resultType; 5110 switch (Opc) { 5111 case UnaryOperator::OffsetOf: 5112 assert(false && "Invalid unary operator"); 5113 break; 5114 5115 case UnaryOperator::PreInc: 5116 case UnaryOperator::PreDec: 5117 case UnaryOperator::PostInc: 5118 case UnaryOperator::PostDec: 5119 resultType = CheckIncrementDecrementOperand(Input, OpLoc, 5120 Opc == UnaryOperator::PreInc || 5121 Opc == UnaryOperator::PostInc); 5122 break; 5123 case UnaryOperator::AddrOf: 5124 resultType = CheckAddressOfOperand(Input, OpLoc); 5125 break; 5126 case UnaryOperator::Deref: 5127 DefaultFunctionArrayConversion(Input); 5128 resultType = CheckIndirectionOperand(Input, OpLoc); 5129 break; 5130 case UnaryOperator::Plus: 5131 case UnaryOperator::Minus: 5132 UsualUnaryConversions(Input); 5133 resultType = Input->getType(); 5134 if (resultType->isDependentType()) 5135 break; 5136 if (resultType->isArithmeticType()) // C99 6.5.3.3p1 5137 break; 5138 else if (getLangOptions().CPlusPlus && // C++ [expr.unary.op]p6-7 5139 resultType->isEnumeralType()) 5140 break; 5141 else if (getLangOptions().CPlusPlus && // C++ [expr.unary.op]p6 5142 Opc == UnaryOperator::Plus && 5143 resultType->isPointerType()) 5144 break; 5145 5146 return ExprError(Diag(OpLoc, diag::err_typecheck_unary_expr) 5147 << resultType << Input->getSourceRange()); 5148 case UnaryOperator::Not: // bitwise complement 5149 UsualUnaryConversions(Input); 5150 resultType = Input->getType(); 5151 if (resultType->isDependentType()) 5152 break; 5153 // C99 6.5.3.3p1. We allow complex int and float as a GCC extension. 5154 if (resultType->isComplexType() || resultType->isComplexIntegerType()) 5155 // C99 does not support '~' for complex conjugation. 5156 Diag(OpLoc, diag::ext_integer_complement_complex) 5157 << resultType << Input->getSourceRange(); 5158 else if (!resultType->isIntegerType()) 5159 return ExprError(Diag(OpLoc, diag::err_typecheck_unary_expr) 5160 << resultType << Input->getSourceRange()); 5161 break; 5162 case UnaryOperator::LNot: // logical negation 5163 // Unlike +/-/~, integer promotions aren't done here (C99 6.5.3.3p5). 5164 DefaultFunctionArrayConversion(Input); 5165 resultType = Input->getType(); 5166 if (resultType->isDependentType()) 5167 break; 5168 if (!resultType->isScalarType()) // C99 6.5.3.3p1 5169 return ExprError(Diag(OpLoc, diag::err_typecheck_unary_expr) 5170 << resultType << Input->getSourceRange()); 5171 // LNot always has type int. C99 6.5.3.3p5. 5172 // In C++, it's bool. C++ 5.3.1p8 5173 resultType = getLangOptions().CPlusPlus ? Context.BoolTy : Context.IntTy; 5174 break; 5175 case UnaryOperator::Real: 5176 case UnaryOperator::Imag: 5177 resultType = CheckRealImagOperand(Input, OpLoc, Opc == UnaryOperator::Real); 5178 break; 5179 case UnaryOperator::Extension: 5180 resultType = Input->getType(); 5181 break; 5182 } 5183 if (resultType.isNull()) 5184 return ExprError(); 5185 5186 InputArg.release(); 5187 return Owned(new (Context) UnaryOperator(Input, Opc, resultType, OpLoc)); 5188} 5189 5190// Unary Operators. 'Tok' is the token for the operator. 5191Action::OwningExprResult Sema::ActOnUnaryOp(Scope *S, SourceLocation OpLoc, 5192 tok::TokenKind Op, ExprArg input) { 5193 Expr *Input = (Expr*)input.get(); 5194 UnaryOperator::Opcode Opc = ConvertTokenKindToUnaryOpcode(Op); 5195 5196 if (getLangOptions().CPlusPlus && Input->getType()->isOverloadableType()) { 5197 // Find all of the overloaded operators visible from this 5198 // point. We perform both an operator-name lookup from the local 5199 // scope and an argument-dependent lookup based on the types of 5200 // the arguments. 5201 FunctionSet Functions; 5202 OverloadedOperatorKind OverOp = UnaryOperator::getOverloadedOperator(Opc); 5203 if (OverOp != OO_None) { 5204 LookupOverloadedOperatorName(OverOp, S, Input->getType(), QualType(), 5205 Functions); 5206 DeclarationName OpName 5207 = Context.DeclarationNames.getCXXOperatorName(OverOp); 5208 ArgumentDependentLookup(OpName, &Input, 1, Functions); 5209 } 5210 5211 return CreateOverloadedUnaryOp(OpLoc, Opc, Functions, move(input)); 5212 } 5213 5214 return CreateBuiltinUnaryOp(OpLoc, Opc, move(input)); 5215} 5216 5217/// ActOnAddrLabel - Parse the GNU address of label extension: "&&foo". 5218Sema::OwningExprResult Sema::ActOnAddrLabel(SourceLocation OpLoc, 5219 SourceLocation LabLoc, 5220 IdentifierInfo *LabelII) { 5221 // Look up the record for this label identifier. 5222 LabelStmt *&LabelDecl = getLabelMap()[LabelII]; 5223 5224 // If we haven't seen this label yet, create a forward reference. It 5225 // will be validated and/or cleaned up in ActOnFinishFunctionBody. 5226 if (LabelDecl == 0) 5227 LabelDecl = new (Context) LabelStmt(LabLoc, LabelII, 0); 5228 5229 // Create the AST node. The address of a label always has type 'void*'. 5230 return Owned(new (Context) AddrLabelExpr(OpLoc, LabLoc, LabelDecl, 5231 Context.getPointerType(Context.VoidTy))); 5232} 5233 5234Sema::OwningExprResult 5235Sema::ActOnStmtExpr(SourceLocation LPLoc, StmtArg substmt, 5236 SourceLocation RPLoc) { // "({..})" 5237 Stmt *SubStmt = static_cast<Stmt*>(substmt.get()); 5238 assert(SubStmt && isa<CompoundStmt>(SubStmt) && "Invalid action invocation!"); 5239 CompoundStmt *Compound = cast<CompoundStmt>(SubStmt); 5240 5241 bool isFileScope = getCurFunctionOrMethodDecl() == 0; 5242 if (isFileScope) 5243 return ExprError(Diag(LPLoc, diag::err_stmtexpr_file_scope)); 5244 5245 // FIXME: there are a variety of strange constraints to enforce here, for 5246 // example, it is not possible to goto into a stmt expression apparently. 5247 // More semantic analysis is needed. 5248 5249 // If there are sub stmts in the compound stmt, take the type of the last one 5250 // as the type of the stmtexpr. 5251 QualType Ty = Context.VoidTy; 5252 5253 if (!Compound->body_empty()) { 5254 Stmt *LastStmt = Compound->body_back(); 5255 // If LastStmt is a label, skip down through into the body. 5256 while (LabelStmt *Label = dyn_cast<LabelStmt>(LastStmt)) 5257 LastStmt = Label->getSubStmt(); 5258 5259 if (Expr *LastExpr = dyn_cast<Expr>(LastStmt)) 5260 Ty = LastExpr->getType(); 5261 } 5262 5263 // FIXME: Check that expression type is complete/non-abstract; statement 5264 // expressions are not lvalues. 5265 5266 substmt.release(); 5267 return Owned(new (Context) StmtExpr(Compound, Ty, LPLoc, RPLoc)); 5268} 5269 5270Sema::OwningExprResult Sema::ActOnBuiltinOffsetOf(Scope *S, 5271 SourceLocation BuiltinLoc, 5272 SourceLocation TypeLoc, 5273 TypeTy *argty, 5274 OffsetOfComponent *CompPtr, 5275 unsigned NumComponents, 5276 SourceLocation RPLoc) { 5277 // FIXME: This function leaks all expressions in the offset components on 5278 // error. 5279 QualType ArgTy = QualType::getFromOpaquePtr(argty); 5280 assert(!ArgTy.isNull() && "Missing type argument!"); 5281 5282 bool Dependent = ArgTy->isDependentType(); 5283 5284 // We must have at least one component that refers to the type, and the first 5285 // one is known to be a field designator. Verify that the ArgTy represents 5286 // a struct/union/class. 5287 if (!Dependent && !ArgTy->isRecordType()) 5288 return ExprError(Diag(TypeLoc, diag::err_offsetof_record_type) << ArgTy); 5289 5290 // FIXME: Type must be complete per C99 7.17p3 because a declaring a variable 5291 // with an incomplete type would be illegal. 5292 5293 // Otherwise, create a null pointer as the base, and iteratively process 5294 // the offsetof designators. 5295 QualType ArgTyPtr = Context.getPointerType(ArgTy); 5296 Expr* Res = new (Context) ImplicitValueInitExpr(ArgTyPtr); 5297 Res = new (Context) UnaryOperator(Res, UnaryOperator::Deref, 5298 ArgTy, SourceLocation()); 5299 5300 // offsetof with non-identifier designators (e.g. "offsetof(x, a.b[c])") are a 5301 // GCC extension, diagnose them. 5302 // FIXME: This diagnostic isn't actually visible because the location is in 5303 // a system header! 5304 if (NumComponents != 1) 5305 Diag(BuiltinLoc, diag::ext_offsetof_extended_field_designator) 5306 << SourceRange(CompPtr[1].LocStart, CompPtr[NumComponents-1].LocEnd); 5307 5308 if (!Dependent) { 5309 bool DidWarnAboutNonPOD = false; 5310 5311 // FIXME: Dependent case loses a lot of information here. And probably 5312 // leaks like a sieve. 5313 for (unsigned i = 0; i != NumComponents; ++i) { 5314 const OffsetOfComponent &OC = CompPtr[i]; 5315 if (OC.isBrackets) { 5316 // Offset of an array sub-field. TODO: Should we allow vector elements? 5317 const ArrayType *AT = Context.getAsArrayType(Res->getType()); 5318 if (!AT) { 5319 Res->Destroy(Context); 5320 return ExprError(Diag(OC.LocEnd, diag::err_offsetof_array_type) 5321 << Res->getType()); 5322 } 5323 5324 // FIXME: C++: Verify that operator[] isn't overloaded. 5325 5326 // Promote the array so it looks more like a normal array subscript 5327 // expression. 5328 DefaultFunctionArrayConversion(Res); 5329 5330 // C99 6.5.2.1p1 5331 Expr *Idx = static_cast<Expr*>(OC.U.E); 5332 // FIXME: Leaks Res 5333 if (!Idx->isTypeDependent() && !Idx->getType()->isIntegerType()) 5334 return ExprError(Diag(Idx->getLocStart(), 5335 diag::err_typecheck_subscript_not_integer) 5336 << Idx->getSourceRange()); 5337 5338 Res = new (Context) ArraySubscriptExpr(Res, Idx, AT->getElementType(), 5339 OC.LocEnd); 5340 continue; 5341 } 5342 5343 const RecordType *RC = Res->getType()->getAs<RecordType>(); 5344 if (!RC) { 5345 Res->Destroy(Context); 5346 return ExprError(Diag(OC.LocEnd, diag::err_offsetof_record_type) 5347 << Res->getType()); 5348 } 5349 5350 // Get the decl corresponding to this. 5351 RecordDecl *RD = RC->getDecl(); 5352 if (CXXRecordDecl *CRD = dyn_cast<CXXRecordDecl>(RD)) { 5353 if (!CRD->isPOD() && !DidWarnAboutNonPOD) { 5354 ExprError(Diag(BuiltinLoc, diag::warn_offsetof_non_pod_type) 5355 << SourceRange(CompPtr[0].LocStart, OC.LocEnd) 5356 << Res->getType()); 5357 DidWarnAboutNonPOD = true; 5358 } 5359 } 5360 5361 FieldDecl *MemberDecl 5362 = dyn_cast_or_null<FieldDecl>(LookupQualifiedName(RD, OC.U.IdentInfo, 5363 LookupMemberName) 5364 .getAsDecl()); 5365 // FIXME: Leaks Res 5366 if (!MemberDecl) 5367 return ExprError(Diag(BuiltinLoc, diag::err_typecheck_no_member) 5368 << OC.U.IdentInfo << SourceRange(OC.LocStart, OC.LocEnd)); 5369 5370 // FIXME: C++: Verify that MemberDecl isn't a static field. 5371 // FIXME: Verify that MemberDecl isn't a bitfield. 5372 if (cast<RecordDecl>(MemberDecl->getDeclContext())->isAnonymousStructOrUnion()) { 5373 Res = BuildAnonymousStructUnionMemberReference( 5374 SourceLocation(), MemberDecl, Res, SourceLocation()).takeAs<Expr>(); 5375 } else { 5376 // MemberDecl->getType() doesn't get the right qualifiers, but it 5377 // doesn't matter here. 5378 Res = new (Context) MemberExpr(Res, false, MemberDecl, OC.LocEnd, 5379 MemberDecl->getType().getNonReferenceType()); 5380 } 5381 } 5382 } 5383 5384 return Owned(new (Context) UnaryOperator(Res, UnaryOperator::OffsetOf, 5385 Context.getSizeType(), BuiltinLoc)); 5386} 5387 5388 5389Sema::OwningExprResult Sema::ActOnTypesCompatibleExpr(SourceLocation BuiltinLoc, 5390 TypeTy *arg1,TypeTy *arg2, 5391 SourceLocation RPLoc) { 5392 QualType argT1 = QualType::getFromOpaquePtr(arg1); 5393 QualType argT2 = QualType::getFromOpaquePtr(arg2); 5394 5395 assert((!argT1.isNull() && !argT2.isNull()) && "Missing type argument(s)"); 5396 5397 if (getLangOptions().CPlusPlus) { 5398 Diag(BuiltinLoc, diag::err_types_compatible_p_in_cplusplus) 5399 << SourceRange(BuiltinLoc, RPLoc); 5400 return ExprError(); 5401 } 5402 5403 return Owned(new (Context) TypesCompatibleExpr(Context.IntTy, BuiltinLoc, 5404 argT1, argT2, RPLoc)); 5405} 5406 5407Sema::OwningExprResult Sema::ActOnChooseExpr(SourceLocation BuiltinLoc, 5408 ExprArg cond, 5409 ExprArg expr1, ExprArg expr2, 5410 SourceLocation RPLoc) { 5411 Expr *CondExpr = static_cast<Expr*>(cond.get()); 5412 Expr *LHSExpr = static_cast<Expr*>(expr1.get()); 5413 Expr *RHSExpr = static_cast<Expr*>(expr2.get()); 5414 5415 assert((CondExpr && LHSExpr && RHSExpr) && "Missing type argument(s)"); 5416 5417 QualType resType; 5418 if (CondExpr->isTypeDependent() || CondExpr->isValueDependent()) { 5419 resType = Context.DependentTy; 5420 } else { 5421 // The conditional expression is required to be a constant expression. 5422 llvm::APSInt condEval(32); 5423 SourceLocation ExpLoc; 5424 if (!CondExpr->isIntegerConstantExpr(condEval, Context, &ExpLoc)) 5425 return ExprError(Diag(ExpLoc, 5426 diag::err_typecheck_choose_expr_requires_constant) 5427 << CondExpr->getSourceRange()); 5428 5429 // If the condition is > zero, then the AST type is the same as the LSHExpr. 5430 resType = condEval.getZExtValue() ? LHSExpr->getType() : RHSExpr->getType(); 5431 } 5432 5433 cond.release(); expr1.release(); expr2.release(); 5434 return Owned(new (Context) ChooseExpr(BuiltinLoc, CondExpr, LHSExpr, RHSExpr, 5435 resType, RPLoc)); 5436} 5437 5438//===----------------------------------------------------------------------===// 5439// Clang Extensions. 5440//===----------------------------------------------------------------------===// 5441 5442/// ActOnBlockStart - This callback is invoked when a block literal is started. 5443void Sema::ActOnBlockStart(SourceLocation CaretLoc, Scope *BlockScope) { 5444 // Analyze block parameters. 5445 BlockSemaInfo *BSI = new BlockSemaInfo(); 5446 5447 // Add BSI to CurBlock. 5448 BSI->PrevBlockInfo = CurBlock; 5449 CurBlock = BSI; 5450 5451 BSI->ReturnType = QualType(); 5452 BSI->TheScope = BlockScope; 5453 BSI->hasBlockDeclRefExprs = false; 5454 BSI->hasPrototype = false; 5455 BSI->SavedFunctionNeedsScopeChecking = CurFunctionNeedsScopeChecking; 5456 CurFunctionNeedsScopeChecking = false; 5457 5458 BSI->TheDecl = BlockDecl::Create(Context, CurContext, CaretLoc); 5459 PushDeclContext(BlockScope, BSI->TheDecl); 5460} 5461 5462void Sema::ActOnBlockArguments(Declarator &ParamInfo, Scope *CurScope) { 5463 assert(ParamInfo.getIdentifier()==0 && "block-id should have no identifier!"); 5464 5465 if (ParamInfo.getNumTypeObjects() == 0 5466 || ParamInfo.getTypeObject(0).Kind != DeclaratorChunk::Function) { 5467 ProcessDeclAttributes(CurScope, CurBlock->TheDecl, ParamInfo); 5468 QualType T = GetTypeForDeclarator(ParamInfo, CurScope); 5469 5470 if (T->isArrayType()) { 5471 Diag(ParamInfo.getSourceRange().getBegin(), 5472 diag::err_block_returns_array); 5473 return; 5474 } 5475 5476 // The parameter list is optional, if there was none, assume (). 5477 if (!T->isFunctionType()) 5478 T = Context.getFunctionType(T, NULL, 0, 0, 0); 5479 5480 CurBlock->hasPrototype = true; 5481 CurBlock->isVariadic = false; 5482 // Check for a valid sentinel attribute on this block. 5483 if (CurBlock->TheDecl->getAttr<SentinelAttr>()) { 5484 Diag(ParamInfo.getAttributes()->getLoc(), 5485 diag::warn_attribute_sentinel_not_variadic) << 1; 5486 // FIXME: remove the attribute. 5487 } 5488 QualType RetTy = T.getTypePtr()->getAsFunctionType()->getResultType(); 5489 5490 // Do not allow returning a objc interface by-value. 5491 if (RetTy->isObjCInterfaceType()) { 5492 Diag(ParamInfo.getSourceRange().getBegin(), 5493 diag::err_object_cannot_be_passed_returned_by_value) << 0 << RetTy; 5494 return; 5495 } 5496 return; 5497 } 5498 5499 // Analyze arguments to block. 5500 assert(ParamInfo.getTypeObject(0).Kind == DeclaratorChunk::Function && 5501 "Not a function declarator!"); 5502 DeclaratorChunk::FunctionTypeInfo &FTI = ParamInfo.getTypeObject(0).Fun; 5503 5504 CurBlock->hasPrototype = FTI.hasPrototype; 5505 CurBlock->isVariadic = true; 5506 5507 // Check for C99 6.7.5.3p10 - foo(void) is a non-varargs function that takes 5508 // no arguments, not a function that takes a single void argument. 5509 if (FTI.hasPrototype && 5510 FTI.NumArgs == 1 && !FTI.isVariadic && FTI.ArgInfo[0].Ident == 0 && 5511 (!FTI.ArgInfo[0].Param.getAs<ParmVarDecl>()->getType().getCVRQualifiers()&& 5512 FTI.ArgInfo[0].Param.getAs<ParmVarDecl>()->getType()->isVoidType())) { 5513 // empty arg list, don't push any params. 5514 CurBlock->isVariadic = false; 5515 } else if (FTI.hasPrototype) { 5516 for (unsigned i = 0, e = FTI.NumArgs; i != e; ++i) 5517 CurBlock->Params.push_back(FTI.ArgInfo[i].Param.getAs<ParmVarDecl>()); 5518 CurBlock->isVariadic = FTI.isVariadic; 5519 } 5520 CurBlock->TheDecl->setParams(Context, CurBlock->Params.data(), 5521 CurBlock->Params.size()); 5522 CurBlock->TheDecl->setIsVariadic(CurBlock->isVariadic); 5523 ProcessDeclAttributes(CurScope, CurBlock->TheDecl, ParamInfo); 5524 for (BlockDecl::param_iterator AI = CurBlock->TheDecl->param_begin(), 5525 E = CurBlock->TheDecl->param_end(); AI != E; ++AI) 5526 // If this has an identifier, add it to the scope stack. 5527 if ((*AI)->getIdentifier()) 5528 PushOnScopeChains(*AI, CurBlock->TheScope); 5529 5530 // Check for a valid sentinel attribute on this block. 5531 if (!CurBlock->isVariadic && 5532 CurBlock->TheDecl->getAttr<SentinelAttr>()) { 5533 Diag(ParamInfo.getAttributes()->getLoc(), 5534 diag::warn_attribute_sentinel_not_variadic) << 1; 5535 // FIXME: remove the attribute. 5536 } 5537 5538 // Analyze the return type. 5539 QualType T = GetTypeForDeclarator(ParamInfo, CurScope); 5540 QualType RetTy = T->getAsFunctionType()->getResultType(); 5541 5542 // Do not allow returning a objc interface by-value. 5543 if (RetTy->isObjCInterfaceType()) { 5544 Diag(ParamInfo.getSourceRange().getBegin(), 5545 diag::err_object_cannot_be_passed_returned_by_value) << 0 << RetTy; 5546 } else if (!RetTy->isDependentType()) 5547 CurBlock->ReturnType = RetTy; 5548} 5549 5550/// ActOnBlockError - If there is an error parsing a block, this callback 5551/// is invoked to pop the information about the block from the action impl. 5552void Sema::ActOnBlockError(SourceLocation CaretLoc, Scope *CurScope) { 5553 // Ensure that CurBlock is deleted. 5554 llvm::OwningPtr<BlockSemaInfo> CC(CurBlock); 5555 5556 CurFunctionNeedsScopeChecking = CurBlock->SavedFunctionNeedsScopeChecking; 5557 5558 // Pop off CurBlock, handle nested blocks. 5559 PopDeclContext(); 5560 CurBlock = CurBlock->PrevBlockInfo; 5561 // FIXME: Delete the ParmVarDecl objects as well??? 5562} 5563 5564/// ActOnBlockStmtExpr - This is called when the body of a block statement 5565/// literal was successfully completed. ^(int x){...} 5566Sema::OwningExprResult Sema::ActOnBlockStmtExpr(SourceLocation CaretLoc, 5567 StmtArg body, Scope *CurScope) { 5568 // If blocks are disabled, emit an error. 5569 if (!LangOpts.Blocks) 5570 Diag(CaretLoc, diag::err_blocks_disable); 5571 5572 // Ensure that CurBlock is deleted. 5573 llvm::OwningPtr<BlockSemaInfo> BSI(CurBlock); 5574 5575 PopDeclContext(); 5576 5577 // Pop off CurBlock, handle nested blocks. 5578 CurBlock = CurBlock->PrevBlockInfo; 5579 5580 QualType RetTy = Context.VoidTy; 5581 if (!BSI->ReturnType.isNull()) 5582 RetTy = BSI->ReturnType; 5583 5584 llvm::SmallVector<QualType, 8> ArgTypes; 5585 for (unsigned i = 0, e = BSI->Params.size(); i != e; ++i) 5586 ArgTypes.push_back(BSI->Params[i]->getType()); 5587 5588 bool NoReturn = BSI->TheDecl->getAttr<NoReturnAttr>(); 5589 QualType BlockTy; 5590 if (!BSI->hasPrototype) 5591 BlockTy = Context.getFunctionType(RetTy, 0, 0, false, 0, false, false, 0, 0, 5592 NoReturn); 5593 else 5594 BlockTy = Context.getFunctionType(RetTy, ArgTypes.data(), ArgTypes.size(), 5595 BSI->isVariadic, 0, false, false, 0, 0, 5596 NoReturn); 5597 5598 // FIXME: Check that return/parameter types are complete/non-abstract 5599 DiagnoseUnusedParameters(BSI->Params.begin(), BSI->Params.end()); 5600 BlockTy = Context.getBlockPointerType(BlockTy); 5601 5602 // If needed, diagnose invalid gotos and switches in the block. 5603 if (CurFunctionNeedsScopeChecking) 5604 DiagnoseInvalidJumps(static_cast<CompoundStmt*>(body.get())); 5605 CurFunctionNeedsScopeChecking = BSI->SavedFunctionNeedsScopeChecking; 5606 5607 BSI->TheDecl->setBody(body.takeAs<CompoundStmt>()); 5608 CheckFallThroughForBlock(BlockTy, BSI->TheDecl->getBody()); 5609 return Owned(new (Context) BlockExpr(BSI->TheDecl, BlockTy, 5610 BSI->hasBlockDeclRefExprs)); 5611} 5612 5613Sema::OwningExprResult Sema::ActOnVAArg(SourceLocation BuiltinLoc, 5614 ExprArg expr, TypeTy *type, 5615 SourceLocation RPLoc) { 5616 QualType T = QualType::getFromOpaquePtr(type); 5617 Expr *E = static_cast<Expr*>(expr.get()); 5618 Expr *OrigExpr = E; 5619 5620 InitBuiltinVaListType(); 5621 5622 // Get the va_list type 5623 QualType VaListType = Context.getBuiltinVaListType(); 5624 if (VaListType->isArrayType()) { 5625 // Deal with implicit array decay; for example, on x86-64, 5626 // va_list is an array, but it's supposed to decay to 5627 // a pointer for va_arg. 5628 VaListType = Context.getArrayDecayedType(VaListType); 5629 // Make sure the input expression also decays appropriately. 5630 UsualUnaryConversions(E); 5631 } else { 5632 // Otherwise, the va_list argument must be an l-value because 5633 // it is modified by va_arg. 5634 if (!E->isTypeDependent() && 5635 CheckForModifiableLvalue(E, BuiltinLoc, *this)) 5636 return ExprError(); 5637 } 5638 5639 if (!E->isTypeDependent() && 5640 !Context.hasSameType(VaListType, E->getType())) { 5641 return ExprError(Diag(E->getLocStart(), 5642 diag::err_first_argument_to_va_arg_not_of_type_va_list) 5643 << OrigExpr->getType() << E->getSourceRange()); 5644 } 5645 5646 // FIXME: Check that type is complete/non-abstract 5647 // FIXME: Warn if a non-POD type is passed in. 5648 5649 expr.release(); 5650 return Owned(new (Context) VAArgExpr(BuiltinLoc, E, T.getNonReferenceType(), 5651 RPLoc)); 5652} 5653 5654Sema::OwningExprResult Sema::ActOnGNUNullExpr(SourceLocation TokenLoc) { 5655 // The type of __null will be int or long, depending on the size of 5656 // pointers on the target. 5657 QualType Ty; 5658 if (Context.Target.getPointerWidth(0) == Context.Target.getIntWidth()) 5659 Ty = Context.IntTy; 5660 else 5661 Ty = Context.LongTy; 5662 5663 return Owned(new (Context) GNUNullExpr(Ty, TokenLoc)); 5664} 5665 5666bool Sema::DiagnoseAssignmentResult(AssignConvertType ConvTy, 5667 SourceLocation Loc, 5668 QualType DstType, QualType SrcType, 5669 Expr *SrcExpr, const char *Flavor) { 5670 // Decode the result (notice that AST's are still created for extensions). 5671 bool isInvalid = false; 5672 unsigned DiagKind; 5673 switch (ConvTy) { 5674 default: assert(0 && "Unknown conversion type"); 5675 case Compatible: return false; 5676 case PointerToInt: 5677 DiagKind = diag::ext_typecheck_convert_pointer_int; 5678 break; 5679 case IntToPointer: 5680 DiagKind = diag::ext_typecheck_convert_int_pointer; 5681 break; 5682 case IncompatiblePointer: 5683 DiagKind = diag::ext_typecheck_convert_incompatible_pointer; 5684 break; 5685 case IncompatiblePointerSign: 5686 DiagKind = diag::ext_typecheck_convert_incompatible_pointer_sign; 5687 break; 5688 case FunctionVoidPointer: 5689 DiagKind = diag::ext_typecheck_convert_pointer_void_func; 5690 break; 5691 case CompatiblePointerDiscardsQualifiers: 5692 // If the qualifiers lost were because we were applying the 5693 // (deprecated) C++ conversion from a string literal to a char* 5694 // (or wchar_t*), then there was no error (C++ 4.2p2). FIXME: 5695 // Ideally, this check would be performed in 5696 // CheckPointerTypesForAssignment. However, that would require a 5697 // bit of refactoring (so that the second argument is an 5698 // expression, rather than a type), which should be done as part 5699 // of a larger effort to fix CheckPointerTypesForAssignment for 5700 // C++ semantics. 5701 if (getLangOptions().CPlusPlus && 5702 IsStringLiteralToNonConstPointerConversion(SrcExpr, DstType)) 5703 return false; 5704 DiagKind = diag::ext_typecheck_convert_discards_qualifiers; 5705 break; 5706 case IntToBlockPointer: 5707 DiagKind = diag::err_int_to_block_pointer; 5708 break; 5709 case IncompatibleBlockPointer: 5710 DiagKind = diag::err_typecheck_convert_incompatible_block_pointer; 5711 break; 5712 case IncompatibleObjCQualifiedId: 5713 // FIXME: Diagnose the problem in ObjCQualifiedIdTypesAreCompatible, since 5714 // it can give a more specific diagnostic. 5715 DiagKind = diag::warn_incompatible_qualified_id; 5716 break; 5717 case IncompatibleVectors: 5718 DiagKind = diag::warn_incompatible_vectors; 5719 break; 5720 case Incompatible: 5721 DiagKind = diag::err_typecheck_convert_incompatible; 5722 isInvalid = true; 5723 break; 5724 } 5725 5726 Diag(Loc, DiagKind) << DstType << SrcType << Flavor 5727 << SrcExpr->getSourceRange(); 5728 return isInvalid; 5729} 5730 5731bool Sema::VerifyIntegerConstantExpression(const Expr *E, llvm::APSInt *Result){ 5732 llvm::APSInt ICEResult; 5733 if (E->isIntegerConstantExpr(ICEResult, Context)) { 5734 if (Result) 5735 *Result = ICEResult; 5736 return false; 5737 } 5738 5739 Expr::EvalResult EvalResult; 5740 5741 if (!E->Evaluate(EvalResult, Context) || !EvalResult.Val.isInt() || 5742 EvalResult.HasSideEffects) { 5743 Diag(E->getExprLoc(), diag::err_expr_not_ice) << E->getSourceRange(); 5744 5745 if (EvalResult.Diag) { 5746 // We only show the note if it's not the usual "invalid subexpression" 5747 // or if it's actually in a subexpression. 5748 if (EvalResult.Diag != diag::note_invalid_subexpr_in_ice || 5749 E->IgnoreParens() != EvalResult.DiagExpr->IgnoreParens()) 5750 Diag(EvalResult.DiagLoc, EvalResult.Diag); 5751 } 5752 5753 return true; 5754 } 5755 5756 Diag(E->getExprLoc(), diag::ext_expr_not_ice) << 5757 E->getSourceRange(); 5758 5759 if (EvalResult.Diag && 5760 Diags.getDiagnosticLevel(diag::ext_expr_not_ice) != Diagnostic::Ignored) 5761 Diag(EvalResult.DiagLoc, EvalResult.Diag); 5762 5763 if (Result) 5764 *Result = EvalResult.Val.getInt(); 5765 return false; 5766} 5767 5768Sema::ExpressionEvaluationContext 5769Sema::PushExpressionEvaluationContext(ExpressionEvaluationContext NewContext) { 5770 // Introduce a new set of potentially referenced declarations to the stack. 5771 if (NewContext == PotentiallyPotentiallyEvaluated) 5772 PotentiallyReferencedDeclStack.push_back(PotentiallyReferencedDecls()); 5773 5774 std::swap(ExprEvalContext, NewContext); 5775 return NewContext; 5776} 5777 5778void 5779Sema::PopExpressionEvaluationContext(ExpressionEvaluationContext OldContext, 5780 ExpressionEvaluationContext NewContext) { 5781 ExprEvalContext = NewContext; 5782 5783 if (OldContext == PotentiallyPotentiallyEvaluated) { 5784 // Mark any remaining declarations in the current position of the stack 5785 // as "referenced". If they were not meant to be referenced, semantic 5786 // analysis would have eliminated them (e.g., in ActOnCXXTypeId). 5787 PotentiallyReferencedDecls RemainingDecls; 5788 RemainingDecls.swap(PotentiallyReferencedDeclStack.back()); 5789 PotentiallyReferencedDeclStack.pop_back(); 5790 5791 for (PotentiallyReferencedDecls::iterator I = RemainingDecls.begin(), 5792 IEnd = RemainingDecls.end(); 5793 I != IEnd; ++I) 5794 MarkDeclarationReferenced(I->first, I->second); 5795 } 5796} 5797 5798/// \brief Note that the given declaration was referenced in the source code. 5799/// 5800/// This routine should be invoke whenever a given declaration is referenced 5801/// in the source code, and where that reference occurred. If this declaration 5802/// reference means that the the declaration is used (C++ [basic.def.odr]p2, 5803/// C99 6.9p3), then the declaration will be marked as used. 5804/// 5805/// \param Loc the location where the declaration was referenced. 5806/// 5807/// \param D the declaration that has been referenced by the source code. 5808void Sema::MarkDeclarationReferenced(SourceLocation Loc, Decl *D) { 5809 assert(D && "No declaration?"); 5810 5811 if (D->isUsed()) 5812 return; 5813 5814 // Mark a parameter declaration "used", regardless of whether we're in a 5815 // template or not. 5816 if (isa<ParmVarDecl>(D)) 5817 D->setUsed(true); 5818 5819 // Do not mark anything as "used" within a dependent context; wait for 5820 // an instantiation. 5821 if (CurContext->isDependentContext()) 5822 return; 5823 5824 switch (ExprEvalContext) { 5825 case Unevaluated: 5826 // We are in an expression that is not potentially evaluated; do nothing. 5827 return; 5828 5829 case PotentiallyEvaluated: 5830 // We are in a potentially-evaluated expression, so this declaration is 5831 // "used"; handle this below. 5832 break; 5833 5834 case PotentiallyPotentiallyEvaluated: 5835 // We are in an expression that may be potentially evaluated; queue this 5836 // declaration reference until we know whether the expression is 5837 // potentially evaluated. 5838 PotentiallyReferencedDeclStack.back().push_back(std::make_pair(Loc, D)); 5839 return; 5840 } 5841 5842 // Note that this declaration has been used. 5843 if (CXXConstructorDecl *Constructor = dyn_cast<CXXConstructorDecl>(D)) { 5844 unsigned TypeQuals; 5845 if (Constructor->isImplicit() && Constructor->isDefaultConstructor()) { 5846 if (!Constructor->isUsed()) 5847 DefineImplicitDefaultConstructor(Loc, Constructor); 5848 } else if (Constructor->isImplicit() && 5849 Constructor->isCopyConstructor(Context, TypeQuals)) { 5850 if (!Constructor->isUsed()) 5851 DefineImplicitCopyConstructor(Loc, Constructor, TypeQuals); 5852 } 5853 } else if (CXXDestructorDecl *Destructor = dyn_cast<CXXDestructorDecl>(D)) { 5854 if (Destructor->isImplicit() && !Destructor->isUsed()) 5855 DefineImplicitDestructor(Loc, Destructor); 5856 5857 } else if (CXXMethodDecl *MethodDecl = dyn_cast<CXXMethodDecl>(D)) { 5858 if (MethodDecl->isImplicit() && MethodDecl->isOverloadedOperator() && 5859 MethodDecl->getOverloadedOperator() == OO_Equal) { 5860 if (!MethodDecl->isUsed()) 5861 DefineImplicitOverloadedAssign(Loc, MethodDecl); 5862 } 5863 } 5864 if (FunctionDecl *Function = dyn_cast<FunctionDecl>(D)) { 5865 // Implicit instantiation of function templates and member functions of 5866 // class templates. 5867 if (!Function->getBody()) { 5868 // FIXME: distinguish between implicit instantiations of function 5869 // templates and explicit specializations (the latter don't get 5870 // instantiated, naturally). 5871 if (Function->getInstantiatedFromMemberFunction() || 5872 Function->getPrimaryTemplate()) 5873 PendingImplicitInstantiations.push_back(std::make_pair(Function, Loc)); 5874 } 5875 5876 5877 // FIXME: keep track of references to static functions 5878 Function->setUsed(true); 5879 return; 5880 } 5881 5882 if (VarDecl *Var = dyn_cast<VarDecl>(D)) { 5883 // Implicit instantiation of static data members of class templates. 5884 // FIXME: distinguish between implicit instantiations (which we need to 5885 // actually instantiate) and explicit specializations. 5886 if (Var->isStaticDataMember() && 5887 Var->getInstantiatedFromStaticDataMember()) 5888 PendingImplicitInstantiations.push_back(std::make_pair(Var, Loc)); 5889 5890 // FIXME: keep track of references to static data? 5891 5892 D->setUsed(true); 5893 return; 5894} 5895} 5896 5897