SemaExpr.cpp revision e076c640003e4d5da7e4f03b31f70b81e9d2c963
1//===--- SemaExpr.cpp - Semantic Analysis for Expressions -----------------===// 2// 3// The LLVM Compiler Infrastructure 4// 5// This file is distributed under the University of Illinois Open Source 6// License. See LICENSE.TXT for details. 7// 8//===----------------------------------------------------------------------===// 9// 10// This file implements semantic analysis for expressions. 11// 12//===----------------------------------------------------------------------===// 13 14#include "Sema.h" 15#include "Lookup.h" 16#include "clang/AST/ASTContext.h" 17#include "clang/AST/DeclObjC.h" 18#include "clang/AST/DeclTemplate.h" 19#include "clang/AST/ExprCXX.h" 20#include "clang/AST/ExprObjC.h" 21#include "clang/Basic/PartialDiagnostic.h" 22#include "clang/Basic/SourceManager.h" 23#include "clang/Basic/TargetInfo.h" 24#include "clang/Lex/LiteralSupport.h" 25#include "clang/Lex/Preprocessor.h" 26#include "clang/Parse/DeclSpec.h" 27#include "clang/Parse/Designator.h" 28#include "clang/Parse/Scope.h" 29#include "clang/Parse/Template.h" 30using namespace clang; 31 32 33/// \brief Determine whether the use of this declaration is valid, and 34/// emit any corresponding diagnostics. 35/// 36/// This routine diagnoses various problems with referencing 37/// declarations that can occur when using a declaration. For example, 38/// it might warn if a deprecated or unavailable declaration is being 39/// used, or produce an error (and return true) if a C++0x deleted 40/// function is being used. 41/// 42/// If IgnoreDeprecated is set to true, this should not want about deprecated 43/// decls. 44/// 45/// \returns true if there was an error (this declaration cannot be 46/// referenced), false otherwise. 47/// 48bool Sema::DiagnoseUseOfDecl(NamedDecl *D, SourceLocation Loc) { 49 // See if the decl is deprecated. 50 if (D->getAttr<DeprecatedAttr>()) { 51 EmitDeprecationWarning(D, Loc); 52 } 53 54 // See if the decl is unavailable 55 if (D->getAttr<UnavailableAttr>()) { 56 Diag(Loc, diag::warn_unavailable) << D->getDeclName(); 57 Diag(D->getLocation(), diag::note_unavailable_here) << 0; 58 } 59 60 // See if this is a deleted function. 61 if (FunctionDecl *FD = dyn_cast<FunctionDecl>(D)) { 62 if (FD->isDeleted()) { 63 Diag(Loc, diag::err_deleted_function_use); 64 Diag(D->getLocation(), diag::note_unavailable_here) << true; 65 return true; 66 } 67 } 68 69 return false; 70} 71 72/// DiagnoseSentinelCalls - This routine checks on method dispatch calls 73/// (and other functions in future), which have been declared with sentinel 74/// attribute. It warns if call does not have the sentinel argument. 75/// 76void Sema::DiagnoseSentinelCalls(NamedDecl *D, SourceLocation Loc, 77 Expr **Args, unsigned NumArgs) { 78 const SentinelAttr *attr = D->getAttr<SentinelAttr>(); 79 if (!attr) 80 return; 81 int sentinelPos = attr->getSentinel(); 82 int nullPos = attr->getNullPos(); 83 84 // FIXME. ObjCMethodDecl and FunctionDecl need be derived from the same common 85 // base class. Then we won't be needing two versions of the same code. 86 unsigned int i = 0; 87 bool warnNotEnoughArgs = false; 88 int isMethod = 0; 89 if (ObjCMethodDecl *MD = dyn_cast<ObjCMethodDecl>(D)) { 90 // skip over named parameters. 91 ObjCMethodDecl::param_iterator P, E = MD->param_end(); 92 for (P = MD->param_begin(); (P != E && i < NumArgs); ++P) { 93 if (nullPos) 94 --nullPos; 95 else 96 ++i; 97 } 98 warnNotEnoughArgs = (P != E || i >= NumArgs); 99 isMethod = 1; 100 } else if (FunctionDecl *FD = dyn_cast<FunctionDecl>(D)) { 101 // skip over named parameters. 102 ObjCMethodDecl::param_iterator P, E = FD->param_end(); 103 for (P = FD->param_begin(); (P != E && i < NumArgs); ++P) { 104 if (nullPos) 105 --nullPos; 106 else 107 ++i; 108 } 109 warnNotEnoughArgs = (P != E || i >= NumArgs); 110 } else if (VarDecl *V = dyn_cast<VarDecl>(D)) { 111 // block or function pointer call. 112 QualType Ty = V->getType(); 113 if (Ty->isBlockPointerType() || Ty->isFunctionPointerType()) { 114 const FunctionType *FT = Ty->isFunctionPointerType() 115 ? Ty->getAs<PointerType>()->getPointeeType()->getAs<FunctionType>() 116 : Ty->getAs<BlockPointerType>()->getPointeeType()->getAs<FunctionType>(); 117 if (const FunctionProtoType *Proto = dyn_cast<FunctionProtoType>(FT)) { 118 unsigned NumArgsInProto = Proto->getNumArgs(); 119 unsigned k; 120 for (k = 0; (k != NumArgsInProto && i < NumArgs); k++) { 121 if (nullPos) 122 --nullPos; 123 else 124 ++i; 125 } 126 warnNotEnoughArgs = (k != NumArgsInProto || i >= NumArgs); 127 } 128 if (Ty->isBlockPointerType()) 129 isMethod = 2; 130 } else 131 return; 132 } else 133 return; 134 135 if (warnNotEnoughArgs) { 136 Diag(Loc, diag::warn_not_enough_argument) << D->getDeclName(); 137 Diag(D->getLocation(), diag::note_sentinel_here) << isMethod; 138 return; 139 } 140 int sentinel = i; 141 while (sentinelPos > 0 && i < NumArgs-1) { 142 --sentinelPos; 143 ++i; 144 } 145 if (sentinelPos > 0) { 146 Diag(Loc, diag::warn_not_enough_argument) << D->getDeclName(); 147 Diag(D->getLocation(), diag::note_sentinel_here) << isMethod; 148 return; 149 } 150 while (i < NumArgs-1) { 151 ++i; 152 ++sentinel; 153 } 154 Expr *sentinelExpr = Args[sentinel]; 155 if (sentinelExpr && (!isa<GNUNullExpr>(sentinelExpr) && 156 (!sentinelExpr->getType()->isPointerType() || 157 !sentinelExpr->isNullPointerConstant(Context, 158 Expr::NPC_ValueDependentIsNull)))) { 159 Diag(Loc, diag::warn_missing_sentinel) << isMethod; 160 Diag(D->getLocation(), diag::note_sentinel_here) << isMethod; 161 } 162 return; 163} 164 165SourceRange Sema::getExprRange(ExprTy *E) const { 166 Expr *Ex = (Expr *)E; 167 return Ex? Ex->getSourceRange() : SourceRange(); 168} 169 170//===----------------------------------------------------------------------===// 171// Standard Promotions and Conversions 172//===----------------------------------------------------------------------===// 173 174/// DefaultFunctionArrayConversion (C99 6.3.2.1p3, C99 6.3.2.1p4). 175void Sema::DefaultFunctionArrayConversion(Expr *&E) { 176 QualType Ty = E->getType(); 177 assert(!Ty.isNull() && "DefaultFunctionArrayConversion - missing type"); 178 179 if (Ty->isFunctionType()) 180 ImpCastExprToType(E, Context.getPointerType(Ty), 181 CastExpr::CK_FunctionToPointerDecay); 182 else if (Ty->isArrayType()) { 183 // In C90 mode, arrays only promote to pointers if the array expression is 184 // an lvalue. The relevant legalese is C90 6.2.2.1p3: "an lvalue that has 185 // type 'array of type' is converted to an expression that has type 'pointer 186 // to type'...". In C99 this was changed to: C99 6.3.2.1p3: "an expression 187 // that has type 'array of type' ...". The relevant change is "an lvalue" 188 // (C90) to "an expression" (C99). 189 // 190 // C++ 4.2p1: 191 // An lvalue or rvalue of type "array of N T" or "array of unknown bound of 192 // T" can be converted to an rvalue of type "pointer to T". 193 // 194 if (getLangOptions().C99 || getLangOptions().CPlusPlus || 195 E->isLvalue(Context) == Expr::LV_Valid) 196 ImpCastExprToType(E, Context.getArrayDecayedType(Ty), 197 CastExpr::CK_ArrayToPointerDecay); 198 } 199} 200 201/// UsualUnaryConversions - Performs various conversions that are common to most 202/// operators (C99 6.3). The conversions of array and function types are 203/// sometimes surpressed. For example, the array->pointer conversion doesn't 204/// apply if the array is an argument to the sizeof or address (&) operators. 205/// In these instances, this routine should *not* be called. 206Expr *Sema::UsualUnaryConversions(Expr *&Expr) { 207 QualType Ty = Expr->getType(); 208 assert(!Ty.isNull() && "UsualUnaryConversions - missing type"); 209 210 // C99 6.3.1.1p2: 211 // 212 // The following may be used in an expression wherever an int or 213 // unsigned int may be used: 214 // - an object or expression with an integer type whose integer 215 // conversion rank is less than or equal to the rank of int 216 // and unsigned int. 217 // - A bit-field of type _Bool, int, signed int, or unsigned int. 218 // 219 // If an int can represent all values of the original type, the 220 // value is converted to an int; otherwise, it is converted to an 221 // unsigned int. These are called the integer promotions. All 222 // other types are unchanged by the integer promotions. 223 QualType PTy = Context.isPromotableBitField(Expr); 224 if (!PTy.isNull()) { 225 ImpCastExprToType(Expr, PTy, CastExpr::CK_IntegralCast); 226 return Expr; 227 } 228 if (Ty->isPromotableIntegerType()) { 229 QualType PT = Context.getPromotedIntegerType(Ty); 230 ImpCastExprToType(Expr, PT, CastExpr::CK_IntegralCast); 231 return Expr; 232 } 233 234 DefaultFunctionArrayConversion(Expr); 235 return Expr; 236} 237 238/// DefaultArgumentPromotion (C99 6.5.2.2p6). Used for function calls that 239/// do not have a prototype. Arguments that have type float are promoted to 240/// double. All other argument types are converted by UsualUnaryConversions(). 241void Sema::DefaultArgumentPromotion(Expr *&Expr) { 242 QualType Ty = Expr->getType(); 243 assert(!Ty.isNull() && "DefaultArgumentPromotion - missing type"); 244 245 // If this is a 'float' (CVR qualified or typedef) promote to double. 246 if (const BuiltinType *BT = Ty->getAs<BuiltinType>()) 247 if (BT->getKind() == BuiltinType::Float) 248 return ImpCastExprToType(Expr, Context.DoubleTy, 249 CastExpr::CK_FloatingCast); 250 251 UsualUnaryConversions(Expr); 252} 253 254/// DefaultVariadicArgumentPromotion - Like DefaultArgumentPromotion, but 255/// will warn if the resulting type is not a POD type, and rejects ObjC 256/// interfaces passed by value. This returns true if the argument type is 257/// completely illegal. 258bool Sema::DefaultVariadicArgumentPromotion(Expr *&Expr, VariadicCallType CT) { 259 DefaultArgumentPromotion(Expr); 260 261 if (Expr->getType()->isObjCInterfaceType()) { 262 Diag(Expr->getLocStart(), 263 diag::err_cannot_pass_objc_interface_to_vararg) 264 << Expr->getType() << CT; 265 return true; 266 } 267 268 if (!Expr->getType()->isPODType()) 269 Diag(Expr->getLocStart(), diag::warn_cannot_pass_non_pod_arg_to_vararg) 270 << Expr->getType() << CT; 271 272 return false; 273} 274 275 276/// UsualArithmeticConversions - Performs various conversions that are common to 277/// binary operators (C99 6.3.1.8). If both operands aren't arithmetic, this 278/// routine returns the first non-arithmetic type found. The client is 279/// responsible for emitting appropriate error diagnostics. 280/// FIXME: verify the conversion rules for "complex int" are consistent with 281/// GCC. 282QualType Sema::UsualArithmeticConversions(Expr *&lhsExpr, Expr *&rhsExpr, 283 bool isCompAssign) { 284 if (!isCompAssign) 285 UsualUnaryConversions(lhsExpr); 286 287 UsualUnaryConversions(rhsExpr); 288 289 // For conversion purposes, we ignore any qualifiers. 290 // For example, "const float" and "float" are equivalent. 291 QualType lhs = 292 Context.getCanonicalType(lhsExpr->getType()).getUnqualifiedType(); 293 QualType rhs = 294 Context.getCanonicalType(rhsExpr->getType()).getUnqualifiedType(); 295 296 // If both types are identical, no conversion is needed. 297 if (lhs == rhs) 298 return lhs; 299 300 // If either side is a non-arithmetic type (e.g. a pointer), we are done. 301 // The caller can deal with this (e.g. pointer + int). 302 if (!lhs->isArithmeticType() || !rhs->isArithmeticType()) 303 return lhs; 304 305 // Perform bitfield promotions. 306 QualType LHSBitfieldPromoteTy = Context.isPromotableBitField(lhsExpr); 307 if (!LHSBitfieldPromoteTy.isNull()) 308 lhs = LHSBitfieldPromoteTy; 309 QualType RHSBitfieldPromoteTy = Context.isPromotableBitField(rhsExpr); 310 if (!RHSBitfieldPromoteTy.isNull()) 311 rhs = RHSBitfieldPromoteTy; 312 313 QualType destType = Context.UsualArithmeticConversionsType(lhs, rhs); 314 if (!isCompAssign) 315 ImpCastExprToType(lhsExpr, destType, CastExpr::CK_Unknown); 316 ImpCastExprToType(rhsExpr, destType, CastExpr::CK_Unknown); 317 return destType; 318} 319 320//===----------------------------------------------------------------------===// 321// Semantic Analysis for various Expression Types 322//===----------------------------------------------------------------------===// 323 324 325/// ActOnStringLiteral - The specified tokens were lexed as pasted string 326/// fragments (e.g. "foo" "bar" L"baz"). The result string has to handle string 327/// concatenation ([C99 5.1.1.2, translation phase #6]), so it may come from 328/// multiple tokens. However, the common case is that StringToks points to one 329/// string. 330/// 331Action::OwningExprResult 332Sema::ActOnStringLiteral(const Token *StringToks, unsigned NumStringToks) { 333 assert(NumStringToks && "Must have at least one string!"); 334 335 StringLiteralParser Literal(StringToks, NumStringToks, PP); 336 if (Literal.hadError) 337 return ExprError(); 338 339 llvm::SmallVector<SourceLocation, 4> StringTokLocs; 340 for (unsigned i = 0; i != NumStringToks; ++i) 341 StringTokLocs.push_back(StringToks[i].getLocation()); 342 343 QualType StrTy = Context.CharTy; 344 if (Literal.AnyWide) StrTy = Context.getWCharType(); 345 if (Literal.Pascal) StrTy = Context.UnsignedCharTy; 346 347 // A C++ string literal has a const-qualified element type (C++ 2.13.4p1). 348 if (getLangOptions().CPlusPlus) 349 StrTy.addConst(); 350 351 // Get an array type for the string, according to C99 6.4.5. This includes 352 // the nul terminator character as well as the string length for pascal 353 // strings. 354 StrTy = Context.getConstantArrayType(StrTy, 355 llvm::APInt(32, Literal.GetNumStringChars()+1), 356 ArrayType::Normal, 0); 357 358 // Pass &StringTokLocs[0], StringTokLocs.size() to factory! 359 return Owned(StringLiteral::Create(Context, Literal.GetString(), 360 Literal.GetStringLength(), 361 Literal.AnyWide, StrTy, 362 &StringTokLocs[0], 363 StringTokLocs.size())); 364} 365 366/// ShouldSnapshotBlockValueReference - Return true if a reference inside of 367/// CurBlock to VD should cause it to be snapshotted (as we do for auto 368/// variables defined outside the block) or false if this is not needed (e.g. 369/// for values inside the block or for globals). 370/// 371/// This also keeps the 'hasBlockDeclRefExprs' in the BlockSemaInfo records 372/// up-to-date. 373/// 374static bool ShouldSnapshotBlockValueReference(BlockSemaInfo *CurBlock, 375 ValueDecl *VD) { 376 // If the value is defined inside the block, we couldn't snapshot it even if 377 // we wanted to. 378 if (CurBlock->TheDecl == VD->getDeclContext()) 379 return false; 380 381 // If this is an enum constant or function, it is constant, don't snapshot. 382 if (isa<EnumConstantDecl>(VD) || isa<FunctionDecl>(VD)) 383 return false; 384 385 // If this is a reference to an extern, static, or global variable, no need to 386 // snapshot it. 387 // FIXME: What about 'const' variables in C++? 388 if (const VarDecl *Var = dyn_cast<VarDecl>(VD)) 389 if (!Var->hasLocalStorage()) 390 return false; 391 392 // Blocks that have these can't be constant. 393 CurBlock->hasBlockDeclRefExprs = true; 394 395 // If we have nested blocks, the decl may be declared in an outer block (in 396 // which case that outer block doesn't get "hasBlockDeclRefExprs") or it may 397 // be defined outside all of the current blocks (in which case the blocks do 398 // all get the bit). Walk the nesting chain. 399 for (BlockSemaInfo *NextBlock = CurBlock->PrevBlockInfo; NextBlock; 400 NextBlock = NextBlock->PrevBlockInfo) { 401 // If we found the defining block for the variable, don't mark the block as 402 // having a reference outside it. 403 if (NextBlock->TheDecl == VD->getDeclContext()) 404 break; 405 406 // Otherwise, the DeclRef from the inner block causes the outer one to need 407 // a snapshot as well. 408 NextBlock->hasBlockDeclRefExprs = true; 409 } 410 411 return true; 412} 413 414 415 416/// BuildDeclRefExpr - Build a DeclRefExpr. 417Sema::OwningExprResult 418Sema::BuildDeclRefExpr(NamedDecl *D, QualType Ty, SourceLocation Loc, 419 const CXXScopeSpec *SS) { 420 assert(!isa<OverloadedFunctionDecl>(D)); 421 422 if (Context.getCanonicalType(Ty) == Context.UndeducedAutoTy) { 423 Diag(Loc, 424 diag::err_auto_variable_cannot_appear_in_own_initializer) 425 << D->getDeclName(); 426 return ExprError(); 427 } 428 429 if (const VarDecl *VD = dyn_cast<VarDecl>(D)) { 430 if (const CXXMethodDecl *MD = dyn_cast<CXXMethodDecl>(CurContext)) { 431 if (const FunctionDecl *FD = MD->getParent()->isLocalClass()) { 432 if (VD->hasLocalStorage() && VD->getDeclContext() != CurContext) { 433 Diag(Loc, diag::err_reference_to_local_var_in_enclosing_function) 434 << D->getIdentifier() << FD->getDeclName(); 435 Diag(D->getLocation(), diag::note_local_variable_declared_here) 436 << D->getIdentifier(); 437 return ExprError(); 438 } 439 } 440 } 441 } 442 443 MarkDeclarationReferenced(Loc, D); 444 445 return Owned(DeclRefExpr::Create(Context, 446 SS? (NestedNameSpecifier *)SS->getScopeRep() : 0, 447 SS? SS->getRange() : SourceRange(), 448 D, Loc, Ty)); 449} 450 451/// getObjectForAnonymousRecordDecl - Retrieve the (unnamed) field or 452/// variable corresponding to the anonymous union or struct whose type 453/// is Record. 454static Decl *getObjectForAnonymousRecordDecl(ASTContext &Context, 455 RecordDecl *Record) { 456 assert(Record->isAnonymousStructOrUnion() && 457 "Record must be an anonymous struct or union!"); 458 459 // FIXME: Once Decls are directly linked together, this will be an O(1) 460 // operation rather than a slow walk through DeclContext's vector (which 461 // itself will be eliminated). DeclGroups might make this even better. 462 DeclContext *Ctx = Record->getDeclContext(); 463 for (DeclContext::decl_iterator D = Ctx->decls_begin(), 464 DEnd = Ctx->decls_end(); 465 D != DEnd; ++D) { 466 if (*D == Record) { 467 // The object for the anonymous struct/union directly 468 // follows its type in the list of declarations. 469 ++D; 470 assert(D != DEnd && "Missing object for anonymous record"); 471 assert(!cast<NamedDecl>(*D)->getDeclName() && "Decl should be unnamed"); 472 return *D; 473 } 474 } 475 476 assert(false && "Missing object for anonymous record"); 477 return 0; 478} 479 480/// \brief Given a field that represents a member of an anonymous 481/// struct/union, build the path from that field's context to the 482/// actual member. 483/// 484/// Construct the sequence of field member references we'll have to 485/// perform to get to the field in the anonymous union/struct. The 486/// list of members is built from the field outward, so traverse it 487/// backwards to go from an object in the current context to the field 488/// we found. 489/// 490/// \returns The variable from which the field access should begin, 491/// for an anonymous struct/union that is not a member of another 492/// class. Otherwise, returns NULL. 493VarDecl *Sema::BuildAnonymousStructUnionMemberPath(FieldDecl *Field, 494 llvm::SmallVectorImpl<FieldDecl *> &Path) { 495 assert(Field->getDeclContext()->isRecord() && 496 cast<RecordDecl>(Field->getDeclContext())->isAnonymousStructOrUnion() 497 && "Field must be stored inside an anonymous struct or union"); 498 499 Path.push_back(Field); 500 VarDecl *BaseObject = 0; 501 DeclContext *Ctx = Field->getDeclContext(); 502 do { 503 RecordDecl *Record = cast<RecordDecl>(Ctx); 504 Decl *AnonObject = getObjectForAnonymousRecordDecl(Context, Record); 505 if (FieldDecl *AnonField = dyn_cast<FieldDecl>(AnonObject)) 506 Path.push_back(AnonField); 507 else { 508 BaseObject = cast<VarDecl>(AnonObject); 509 break; 510 } 511 Ctx = Ctx->getParent(); 512 } while (Ctx->isRecord() && 513 cast<RecordDecl>(Ctx)->isAnonymousStructOrUnion()); 514 515 return BaseObject; 516} 517 518Sema::OwningExprResult 519Sema::BuildAnonymousStructUnionMemberReference(SourceLocation Loc, 520 FieldDecl *Field, 521 Expr *BaseObjectExpr, 522 SourceLocation OpLoc) { 523 llvm::SmallVector<FieldDecl *, 4> AnonFields; 524 VarDecl *BaseObject = BuildAnonymousStructUnionMemberPath(Field, 525 AnonFields); 526 527 // Build the expression that refers to the base object, from 528 // which we will build a sequence of member references to each 529 // of the anonymous union objects and, eventually, the field we 530 // found via name lookup. 531 bool BaseObjectIsPointer = false; 532 Qualifiers BaseQuals; 533 if (BaseObject) { 534 // BaseObject is an anonymous struct/union variable (and is, 535 // therefore, not part of another non-anonymous record). 536 if (BaseObjectExpr) BaseObjectExpr->Destroy(Context); 537 MarkDeclarationReferenced(Loc, BaseObject); 538 BaseObjectExpr = new (Context) DeclRefExpr(BaseObject,BaseObject->getType(), 539 SourceLocation()); 540 BaseQuals 541 = Context.getCanonicalType(BaseObject->getType()).getQualifiers(); 542 } else if (BaseObjectExpr) { 543 // The caller provided the base object expression. Determine 544 // whether its a pointer and whether it adds any qualifiers to the 545 // anonymous struct/union fields we're looking into. 546 QualType ObjectType = BaseObjectExpr->getType(); 547 if (const PointerType *ObjectPtr = ObjectType->getAs<PointerType>()) { 548 BaseObjectIsPointer = true; 549 ObjectType = ObjectPtr->getPointeeType(); 550 } 551 BaseQuals 552 = Context.getCanonicalType(ObjectType).getQualifiers(); 553 } else { 554 // We've found a member of an anonymous struct/union that is 555 // inside a non-anonymous struct/union, so in a well-formed 556 // program our base object expression is "this". 557 if (CXXMethodDecl *MD = dyn_cast<CXXMethodDecl>(CurContext)) { 558 if (!MD->isStatic()) { 559 QualType AnonFieldType 560 = Context.getTagDeclType( 561 cast<RecordDecl>(AnonFields.back()->getDeclContext())); 562 QualType ThisType = Context.getTagDeclType(MD->getParent()); 563 if ((Context.getCanonicalType(AnonFieldType) 564 == Context.getCanonicalType(ThisType)) || 565 IsDerivedFrom(ThisType, AnonFieldType)) { 566 // Our base object expression is "this". 567 BaseObjectExpr = new (Context) CXXThisExpr(SourceLocation(), 568 MD->getThisType(Context)); 569 BaseObjectIsPointer = true; 570 } 571 } else { 572 return ExprError(Diag(Loc,diag::err_invalid_member_use_in_static_method) 573 << Field->getDeclName()); 574 } 575 BaseQuals = Qualifiers::fromCVRMask(MD->getTypeQualifiers()); 576 } 577 578 if (!BaseObjectExpr) 579 return ExprError(Diag(Loc, diag::err_invalid_non_static_member_use) 580 << Field->getDeclName()); 581 } 582 583 // Build the implicit member references to the field of the 584 // anonymous struct/union. 585 Expr *Result = BaseObjectExpr; 586 Qualifiers ResultQuals = BaseQuals; 587 for (llvm::SmallVector<FieldDecl *, 4>::reverse_iterator 588 FI = AnonFields.rbegin(), FIEnd = AnonFields.rend(); 589 FI != FIEnd; ++FI) { 590 QualType MemberType = (*FI)->getType(); 591 Qualifiers MemberTypeQuals = 592 Context.getCanonicalType(MemberType).getQualifiers(); 593 594 // CVR attributes from the base are picked up by members, 595 // except that 'mutable' members don't pick up 'const'. 596 if ((*FI)->isMutable()) 597 ResultQuals.removeConst(); 598 599 // GC attributes are never picked up by members. 600 ResultQuals.removeObjCGCAttr(); 601 602 // TR 18037 does not allow fields to be declared with address spaces. 603 assert(!MemberTypeQuals.hasAddressSpace()); 604 605 Qualifiers NewQuals = ResultQuals + MemberTypeQuals; 606 if (NewQuals != MemberTypeQuals) 607 MemberType = Context.getQualifiedType(MemberType, NewQuals); 608 609 MarkDeclarationReferenced(Loc, *FI); 610 // FIXME: Might this end up being a qualified name? 611 Result = new (Context) MemberExpr(Result, BaseObjectIsPointer, *FI, 612 OpLoc, MemberType); 613 BaseObjectIsPointer = false; 614 ResultQuals = NewQuals; 615 } 616 617 return Owned(Result); 618} 619 620Sema::OwningExprResult Sema::ActOnIdExpression(Scope *S, 621 const CXXScopeSpec &SS, 622 UnqualifiedId &Name, 623 bool HasTrailingLParen, 624 bool IsAddressOfOperand) { 625 assert(!(IsAddressOfOperand && HasTrailingLParen) && 626 "cannot be direct & operand and have a trailing lparen"); 627 628 if (Name.getKind() == UnqualifiedId::IK_TemplateId) { 629 ASTTemplateArgsPtr TemplateArgsPtr(*this, 630 Name.TemplateId->getTemplateArgs(), 631 Name.TemplateId->NumArgs); 632 return ActOnTemplateIdExpr(SS, 633 TemplateTy::make(Name.TemplateId->Template), 634 Name.TemplateId->TemplateNameLoc, 635 Name.TemplateId->LAngleLoc, 636 TemplateArgsPtr, 637 Name.TemplateId->RAngleLoc); 638 } 639 640 // FIXME: We lose a bunch of source information by doing this. Later, 641 // we'll want to merge ActOnDeclarationNameExpr's logic into 642 // ActOnIdExpression. 643 return ActOnDeclarationNameExpr(S, 644 Name.StartLocation, 645 GetNameFromUnqualifiedId(Name), 646 HasTrailingLParen, 647 &SS, 648 IsAddressOfOperand); 649} 650 651/// ActOnDeclarationNameExpr - The parser has read some kind of name 652/// (e.g., a C++ id-expression (C++ [expr.prim]p1)). This routine 653/// performs lookup on that name and returns an expression that refers 654/// to that name. This routine isn't directly called from the parser, 655/// because the parser doesn't know about DeclarationName. Rather, 656/// this routine is called by ActOnIdExpression, which contains a 657/// parsed UnqualifiedId. 658/// 659/// HasTrailingLParen indicates whether this identifier is used in a 660/// function call context. LookupCtx is only used for a C++ 661/// qualified-id (foo::bar) to indicate the class or namespace that 662/// the identifier must be a member of. 663/// 664/// isAddressOfOperand means that this expression is the direct operand 665/// of an address-of operator. This matters because this is the only 666/// situation where a qualified name referencing a non-static member may 667/// appear outside a member function of this class. 668Sema::OwningExprResult 669Sema::ActOnDeclarationNameExpr(Scope *S, SourceLocation Loc, 670 DeclarationName Name, bool HasTrailingLParen, 671 const CXXScopeSpec *SS, 672 bool isAddressOfOperand) { 673 // Could be enum-constant, value decl, instance variable, etc. 674 if (SS && SS->isInvalid()) 675 return ExprError(); 676 677 // Determine whether this is a member of an unknown specialization. 678 if (SS && SS->isSet() && !computeDeclContext(*SS, false)) { 679 return Owned(new (Context) DependentScopeDeclRefExpr(Name, Context.DependentTy, 680 Loc, SS->getRange(), 681 static_cast<NestedNameSpecifier *>(SS->getScopeRep()), 682 isAddressOfOperand)); 683 } 684 685 LookupResult Lookup(*this, Name, Loc, LookupOrdinaryName); 686 LookupParsedName(Lookup, S, SS, true); 687 688 if (Lookup.isAmbiguous()) 689 return ExprError(); 690 691 // If this reference is in an Objective-C method, then ivar lookup happens as 692 // well. 693 IdentifierInfo *II = Name.getAsIdentifierInfo(); 694 if (II && getCurMethodDecl()) { 695 // There are two cases to handle here. 1) scoped lookup could have failed, 696 // in which case we should look for an ivar. 2) scoped lookup could have 697 // found a decl, but that decl is outside the current instance method (i.e. 698 // a global variable). In these two cases, we do a lookup for an ivar with 699 // this name, if the lookup sucedes, we replace it our current decl. 700 701 // FIXME: we should change lookup to do this. 702 703 // If we're in a class method, we don't normally want to look for 704 // ivars. But if we don't find anything else, and there's an 705 // ivar, that's an error. 706 bool IsClassMethod = getCurMethodDecl()->isClassMethod(); 707 708 bool LookForIvars; 709 if (Lookup.empty()) 710 LookForIvars = true; 711 else if (IsClassMethod) 712 LookForIvars = false; 713 else 714 LookForIvars = (Lookup.isSingleResult() && 715 Lookup.getFoundDecl()->isDefinedOutsideFunctionOrMethod()); 716 717 if (LookForIvars) { 718 ObjCInterfaceDecl *IFace = getCurMethodDecl()->getClassInterface(); 719 ObjCInterfaceDecl *ClassDeclared; 720 if (ObjCIvarDecl *IV = IFace->lookupInstanceVariable(II, ClassDeclared)) { 721 // Diagnose using an ivar in a class method. 722 if (IsClassMethod) 723 return ExprError(Diag(Loc, diag::error_ivar_use_in_class_method) 724 << IV->getDeclName()); 725 726 // If we're referencing an invalid decl, just return this as a silent 727 // error node. The error diagnostic was already emitted on the decl. 728 if (IV->isInvalidDecl()) 729 return ExprError(); 730 731 // Check if referencing a field with __attribute__((deprecated)). 732 if (DiagnoseUseOfDecl(IV, Loc)) 733 return ExprError(); 734 735 // Diagnose the use of an ivar outside of the declaring class. 736 if (IV->getAccessControl() == ObjCIvarDecl::Private && 737 ClassDeclared != IFace) 738 Diag(Loc, diag::error_private_ivar_access) << IV->getDeclName(); 739 740 // FIXME: This should use a new expr for a direct reference, don't 741 // turn this into Self->ivar, just return a BareIVarExpr or something. 742 IdentifierInfo &II = Context.Idents.get("self"); 743 UnqualifiedId SelfName; 744 SelfName.setIdentifier(&II, SourceLocation()); 745 CXXScopeSpec SelfScopeSpec; 746 OwningExprResult SelfExpr = ActOnIdExpression(S, SelfScopeSpec, 747 SelfName, false, false); 748 MarkDeclarationReferenced(Loc, IV); 749 return Owned(new (Context) 750 ObjCIvarRefExpr(IV, IV->getType(), Loc, 751 SelfExpr.takeAs<Expr>(), true, true)); 752 } 753 } else if (getCurMethodDecl()->isInstanceMethod()) { 754 // We should warn if a local variable hides an ivar. 755 ObjCInterfaceDecl *IFace = getCurMethodDecl()->getClassInterface(); 756 ObjCInterfaceDecl *ClassDeclared; 757 if (ObjCIvarDecl *IV = IFace->lookupInstanceVariable(II, ClassDeclared)) { 758 if (IV->getAccessControl() != ObjCIvarDecl::Private || 759 IFace == ClassDeclared) 760 Diag(Loc, diag::warn_ivar_use_hidden) << IV->getDeclName(); 761 } 762 } 763 // Needed to implement property "super.method" notation. 764 if (Lookup.empty() && II->isStr("super")) { 765 QualType T; 766 767 if (getCurMethodDecl()->isInstanceMethod()) 768 T = Context.getObjCObjectPointerType(Context.getObjCInterfaceType( 769 getCurMethodDecl()->getClassInterface())); 770 else 771 T = Context.getObjCClassType(); 772 return Owned(new (Context) ObjCSuperExpr(Loc, T)); 773 } 774 } 775 776 // Determine whether this name might be a candidate for 777 // argument-dependent lookup. 778 bool ADL = UseArgumentDependentLookup(SS, Lookup, HasTrailingLParen); 779 780 if (Lookup.empty() && !ADL) { 781 // Otherwise, this could be an implicitly declared function reference (legal 782 // in C90, extension in C99). 783 if (HasTrailingLParen && II && 784 !getLangOptions().CPlusPlus) { // Not in C++. 785 NamedDecl *D = ImplicitlyDefineFunction(Loc, *II, S); 786 if (D) Lookup.addDecl(D); 787 } else { 788 // If this name wasn't predeclared and if this is not a function call, 789 // diagnose the problem. 790 if (SS && !SS->isEmpty()) 791 return ExprError(Diag(Loc, diag::err_no_member) 792 << Name << computeDeclContext(*SS, false) 793 << SS->getRange()); 794 else if (Name.getNameKind() == DeclarationName::CXXOperatorName || 795 Name.getNameKind() == DeclarationName::CXXConversionFunctionName) 796 return ExprError(Diag(Loc, diag::err_undeclared_use) 797 << Name.getAsString()); 798 else 799 return ExprError(Diag(Loc, diag::err_undeclared_var_use) << Name); 800 } 801 } 802 803 if (VarDecl *Var = Lookup.getAsSingle<VarDecl>()) { 804 // Warn about constructs like: 805 // if (void *X = foo()) { ... } else { X }. 806 // In the else block, the pointer is always false. 807 808 // FIXME: In a template instantiation, we don't have scope 809 // information to check this property. 810 if (Var->isDeclaredInCondition() && Var->getType()->isScalarType()) { 811 Scope *CheckS = S; 812 while (CheckS && CheckS->getControlParent()) { 813 if (CheckS->isWithinElse() && 814 CheckS->getControlParent()->isDeclScope(DeclPtrTy::make(Var))) { 815 ExprError(Diag(Loc, diag::warn_value_always_zero) 816 << Var->getDeclName() 817 << (Var->getType()->isPointerType()? 2 : 818 Var->getType()->isBooleanType()? 1 : 0)); 819 break; 820 } 821 822 // Move to the parent of this scope. 823 CheckS = CheckS->getParent(); 824 } 825 } 826 } else if (FunctionDecl *Func = Lookup.getAsSingle<FunctionDecl>()) { 827 if (!getLangOptions().CPlusPlus && !Func->hasPrototype()) { 828 // C99 DR 316 says that, if a function type comes from a 829 // function definition (without a prototype), that type is only 830 // used for checking compatibility. Therefore, when referencing 831 // the function, we pretend that we don't have the full function 832 // type. 833 if (DiagnoseUseOfDecl(Func, Loc)) 834 return ExprError(); 835 836 QualType T = Func->getType(); 837 QualType NoProtoType = T; 838 if (const FunctionProtoType *Proto = T->getAs<FunctionProtoType>()) 839 NoProtoType = Context.getFunctionNoProtoType(Proto->getResultType()); 840 return BuildDeclRefExpr(Func, NoProtoType, Loc, SS); 841 } 842 } 843 844 // &SomeClass::foo is an abstract member reference, regardless of 845 // the nature of foo, but &SomeClass::foo(...) is not. If this is 846 // *not* an abstract member reference, and any of the results is a 847 // class member (which necessarily means they're all class members), 848 // then we make an implicit member reference instead. 849 // 850 // This check considers all the same information as the "needs ADL" 851 // check, but there's no simple logical relationship other than the 852 // fact that they can never be simultaneously true. We could 853 // calculate them both in one pass if that proves important for 854 // performance. 855 if (!ADL) { 856 bool isAbstractMemberPointer = 857 (isAddressOfOperand && SS && !SS->isEmpty()); 858 859 if (!isAbstractMemberPointer && !Lookup.empty() && 860 isa<CXXRecordDecl>((*Lookup.begin())->getDeclContext())) { 861 return BuildImplicitMemberReferenceExpr(SS, Lookup); 862 } 863 } 864 865 assert(Lookup.getResultKind() != LookupResult::FoundUnresolvedValue && 866 "found UnresolvedUsingValueDecl in non-class scope"); 867 868 return BuildDeclarationNameExpr(SS, Lookup, ADL); 869} 870 871/// \brief Cast member's object to its own class if necessary. 872bool 873Sema::PerformObjectMemberConversion(Expr *&From, NamedDecl *Member) { 874 if (FieldDecl *FD = dyn_cast<FieldDecl>(Member)) 875 if (CXXRecordDecl *RD = 876 dyn_cast<CXXRecordDecl>(FD->getDeclContext())) { 877 QualType DestType = 878 Context.getCanonicalType(Context.getTypeDeclType(RD)); 879 if (DestType->isDependentType() || From->getType()->isDependentType()) 880 return false; 881 QualType FromRecordType = From->getType(); 882 QualType DestRecordType = DestType; 883 if (FromRecordType->getAs<PointerType>()) { 884 DestType = Context.getPointerType(DestType); 885 FromRecordType = FromRecordType->getPointeeType(); 886 } 887 if (!Context.hasSameUnqualifiedType(FromRecordType, DestRecordType) && 888 CheckDerivedToBaseConversion(FromRecordType, 889 DestRecordType, 890 From->getSourceRange().getBegin(), 891 From->getSourceRange())) 892 return true; 893 ImpCastExprToType(From, DestType, CastExpr::CK_DerivedToBase, 894 /*isLvalue=*/true); 895 } 896 return false; 897} 898 899/// \brief Build a MemberExpr AST node. 900static MemberExpr *BuildMemberExpr(ASTContext &C, Expr *Base, bool isArrow, 901 const CXXScopeSpec *SS, NamedDecl *Member, 902 SourceLocation Loc, QualType Ty) { 903 if (SS && SS->isSet()) 904 return MemberExpr::Create(C, Base, isArrow, 905 (NestedNameSpecifier *)SS->getScopeRep(), 906 SS->getRange(), Member, Loc, 907 // FIXME: Explicit template argument lists 908 0, Ty); 909 910 return new (C) MemberExpr(Base, isArrow, Member, Loc, Ty); 911} 912 913/// Builds an implicit member access expression from the given 914/// unqualified lookup set, which is known to contain only class 915/// members. 916Sema::OwningExprResult 917Sema::BuildImplicitMemberReferenceExpr(const CXXScopeSpec *SS, 918 LookupResult &R) { 919 NamedDecl *D = R.getAsSingleDecl(Context); 920 SourceLocation Loc = R.getNameLoc(); 921 922 // We may have found a field within an anonymous union or struct 923 // (C++ [class.union]). 924 // FIXME: This needs to happen post-isImplicitMemberReference? 925 if (FieldDecl *FD = dyn_cast<FieldDecl>(D)) 926 if (cast<RecordDecl>(FD->getDeclContext())->isAnonymousStructOrUnion()) 927 return BuildAnonymousStructUnionMemberReference(Loc, FD); 928 929 QualType ThisType; 930 QualType MemberType; 931 if (isImplicitMemberReference(SS, D, Loc, ThisType, MemberType)) { 932 Expr *This = new (Context) CXXThisExpr(SourceLocation(), ThisType); 933 MarkDeclarationReferenced(Loc, D); 934 if (PerformObjectMemberConversion(This, D)) 935 return ExprError(); 936 937 bool ShouldCheckUse = true; 938 if (CXXMethodDecl *MD = dyn_cast<CXXMethodDecl>(D)) { 939 // Don't diagnose the use of a virtual member function unless it's 940 // explicitly qualified. 941 if (MD->isVirtual() && (!SS || !SS->isSet())) 942 ShouldCheckUse = false; 943 } 944 945 if (ShouldCheckUse && DiagnoseUseOfDecl(D, Loc)) 946 return ExprError(); 947 return Owned(BuildMemberExpr(Context, This, true, SS, D, Loc, MemberType)); 948 } 949 950 if (CXXMethodDecl *Method = dyn_cast<CXXMethodDecl>(D)) { 951 if (!Method->isStatic()) 952 return ExprError(Diag(Loc, diag::err_member_call_without_object)); 953 } 954 955 if (isa<FieldDecl>(D)) { 956 if (CXXMethodDecl *MD = dyn_cast<CXXMethodDecl>(CurContext)) { 957 if (MD->isStatic()) { 958 // "invalid use of member 'x' in static member function" 959 Diag(Loc, diag::err_invalid_member_use_in_static_method) 960 << D->getDeclName(); 961 return ExprError(); 962 } 963 } 964 965 // Any other ways we could have found the field in a well-formed 966 // program would have been turned into implicit member expressions 967 // above. 968 Diag(Loc, diag::err_invalid_non_static_member_use) 969 << D->getDeclName(); 970 return ExprError(); 971 } 972 973 // We're not in an implicit member-reference context, but the lookup 974 // results might not require an instance. Try to build a non-member 975 // decl reference. 976 return BuildDeclarationNameExpr(SS, R, /*ADL*/ false); 977} 978 979bool Sema::UseArgumentDependentLookup(const CXXScopeSpec *SS, 980 const LookupResult &R, 981 bool HasTrailingLParen) { 982 // Only when used directly as the postfix-expression of a call. 983 if (!HasTrailingLParen) 984 return false; 985 986 // Never if a scope specifier was provided. 987 if (SS && SS->isSet()) 988 return false; 989 990 // Only in C++ or ObjC++. 991 if (!getLangOptions().CPlusPlus) 992 return false; 993 994 // Turn off ADL when we find certain kinds of declarations during 995 // normal lookup: 996 for (LookupResult::iterator I = R.begin(), E = R.end(); I != E; ++I) { 997 NamedDecl *D = *I; 998 999 // C++0x [basic.lookup.argdep]p3: 1000 // -- a declaration of a class member 1001 // Since using decls preserve this property, we check this on the 1002 // original decl. 1003 if (D->getDeclContext()->isRecord()) 1004 return false; 1005 1006 // C++0x [basic.lookup.argdep]p3: 1007 // -- a block-scope function declaration that is not a 1008 // using-declaration 1009 // NOTE: we also trigger this for function templates (in fact, we 1010 // don't check the decl type at all, since all other decl types 1011 // turn off ADL anyway). 1012 if (isa<UsingShadowDecl>(D)) 1013 D = cast<UsingShadowDecl>(D)->getTargetDecl(); 1014 else if (D->getDeclContext()->isFunctionOrMethod()) 1015 return false; 1016 1017 // C++0x [basic.lookup.argdep]p3: 1018 // -- a declaration that is neither a function or a function 1019 // template 1020 // And also for builtin functions. 1021 if (isa<FunctionDecl>(D)) { 1022 FunctionDecl *FDecl = cast<FunctionDecl>(D); 1023 1024 // But also builtin functions. 1025 if (FDecl->getBuiltinID() && FDecl->isImplicit()) 1026 return false; 1027 } else if (!isa<FunctionTemplateDecl>(D)) 1028 return false; 1029 } 1030 1031 return true; 1032} 1033 1034 1035/// Diagnoses obvious problems with the use of the given declaration 1036/// as an expression. This is only actually called for lookups that 1037/// were not overloaded, and it doesn't promise that the declaration 1038/// will in fact be used. 1039static bool CheckDeclInExpr(Sema &S, SourceLocation Loc, NamedDecl *D) { 1040 if (isa<TypedefDecl>(D)) { 1041 S.Diag(Loc, diag::err_unexpected_typedef) << D->getDeclName(); 1042 return true; 1043 } 1044 1045 if (isa<ObjCInterfaceDecl>(D)) { 1046 S.Diag(Loc, diag::err_unexpected_interface) << D->getDeclName(); 1047 return true; 1048 } 1049 1050 if (isa<NamespaceDecl>(D)) { 1051 S.Diag(Loc, diag::err_unexpected_namespace) << D->getDeclName(); 1052 return true; 1053 } 1054 1055 return false; 1056} 1057 1058Sema::OwningExprResult 1059Sema::BuildDeclarationNameExpr(const CXXScopeSpec *SS, 1060 LookupResult &R, 1061 bool NeedsADL) { 1062 assert(R.getResultKind() != LookupResult::FoundUnresolvedValue); 1063 1064 if (!NeedsADL && !R.isOverloadedResult()) 1065 return BuildDeclarationNameExpr(SS, R.getNameLoc(), R.getFoundDecl()); 1066 1067 // We only need to check the declaration if there's exactly one 1068 // result, because in the overloaded case the results can only be 1069 // functions and function templates. 1070 if (R.isSingleResult() && 1071 CheckDeclInExpr(*this, R.getNameLoc(), R.getFoundDecl())) 1072 return ExprError(); 1073 1074 UnresolvedLookupExpr *ULE 1075 = UnresolvedLookupExpr::Create(Context, 1076 SS ? (NestedNameSpecifier *)SS->getScopeRep() : 0, 1077 SS ? SS->getRange() : SourceRange(), 1078 R.getLookupName(), R.getNameLoc(), 1079 NeedsADL, R.isOverloadedResult()); 1080 for (LookupResult::iterator I = R.begin(), E = R.end(); I != E; ++I) 1081 ULE->addDecl(*I); 1082 1083 return Owned(ULE); 1084} 1085 1086 1087/// \brief Complete semantic analysis for a reference to the given declaration. 1088Sema::OwningExprResult 1089Sema::BuildDeclarationNameExpr(const CXXScopeSpec *SS, 1090 SourceLocation Loc, NamedDecl *D) { 1091 assert(D && "Cannot refer to a NULL declaration"); 1092 assert(!isa<FunctionTemplateDecl>(D) && 1093 "Cannot refer unambiguously to a function template"); 1094 DeclarationName Name = D->getDeclName(); 1095 1096 if (CheckDeclInExpr(*this, Loc, D)) 1097 return ExprError(); 1098 1099 ValueDecl *VD = cast<ValueDecl>(D); 1100 1101 // Check whether this declaration can be used. Note that we suppress 1102 // this check when we're going to perform argument-dependent lookup 1103 // on this function name, because this might not be the function 1104 // that overload resolution actually selects. 1105 if (DiagnoseUseOfDecl(VD, Loc)) 1106 return ExprError(); 1107 1108 // Only create DeclRefExpr's for valid Decl's. 1109 if (VD->isInvalidDecl()) 1110 return ExprError(); 1111 1112 // If the identifier reference is inside a block, and it refers to a value 1113 // that is outside the block, create a BlockDeclRefExpr instead of a 1114 // DeclRefExpr. This ensures the value is treated as a copy-in snapshot when 1115 // the block is formed. 1116 // 1117 // We do not do this for things like enum constants, global variables, etc, 1118 // as they do not get snapshotted. 1119 // 1120 if (CurBlock && ShouldSnapshotBlockValueReference(CurBlock, VD)) { 1121 MarkDeclarationReferenced(Loc, VD); 1122 QualType ExprTy = VD->getType().getNonReferenceType(); 1123 // The BlocksAttr indicates the variable is bound by-reference. 1124 if (VD->getAttr<BlocksAttr>()) 1125 return Owned(new (Context) BlockDeclRefExpr(VD, ExprTy, Loc, true)); 1126 // This is to record that a 'const' was actually synthesize and added. 1127 bool constAdded = !ExprTy.isConstQualified(); 1128 // Variable will be bound by-copy, make it const within the closure. 1129 1130 ExprTy.addConst(); 1131 return Owned(new (Context) BlockDeclRefExpr(VD, ExprTy, Loc, false, 1132 constAdded)); 1133 } 1134 // If this reference is not in a block or if the referenced variable is 1135 // within the block, create a normal DeclRefExpr. 1136 1137 return BuildDeclRefExpr(VD, VD->getType().getNonReferenceType(), Loc, SS); 1138} 1139 1140Sema::OwningExprResult Sema::ActOnPredefinedExpr(SourceLocation Loc, 1141 tok::TokenKind Kind) { 1142 PredefinedExpr::IdentType IT; 1143 1144 switch (Kind) { 1145 default: assert(0 && "Unknown simple primary expr!"); 1146 case tok::kw___func__: IT = PredefinedExpr::Func; break; // [C99 6.4.2.2] 1147 case tok::kw___FUNCTION__: IT = PredefinedExpr::Function; break; 1148 case tok::kw___PRETTY_FUNCTION__: IT = PredefinedExpr::PrettyFunction; break; 1149 } 1150 1151 // Pre-defined identifiers are of type char[x], where x is the length of the 1152 // string. 1153 1154 Decl *currentDecl = getCurFunctionOrMethodDecl(); 1155 if (!currentDecl) { 1156 Diag(Loc, diag::ext_predef_outside_function); 1157 currentDecl = Context.getTranslationUnitDecl(); 1158 } 1159 1160 QualType ResTy; 1161 if (cast<DeclContext>(currentDecl)->isDependentContext()) { 1162 ResTy = Context.DependentTy; 1163 } else { 1164 unsigned Length = 1165 PredefinedExpr::ComputeName(Context, IT, currentDecl).length(); 1166 1167 llvm::APInt LengthI(32, Length + 1); 1168 ResTy = Context.CharTy.withConst(); 1169 ResTy = Context.getConstantArrayType(ResTy, LengthI, ArrayType::Normal, 0); 1170 } 1171 return Owned(new (Context) PredefinedExpr(Loc, ResTy, IT)); 1172} 1173 1174Sema::OwningExprResult Sema::ActOnCharacterConstant(const Token &Tok) { 1175 llvm::SmallString<16> CharBuffer; 1176 CharBuffer.resize(Tok.getLength()); 1177 const char *ThisTokBegin = &CharBuffer[0]; 1178 unsigned ActualLength = PP.getSpelling(Tok, ThisTokBegin); 1179 1180 CharLiteralParser Literal(ThisTokBegin, ThisTokBegin+ActualLength, 1181 Tok.getLocation(), PP); 1182 if (Literal.hadError()) 1183 return ExprError(); 1184 1185 QualType type = getLangOptions().CPlusPlus ? Context.CharTy : Context.IntTy; 1186 1187 return Owned(new (Context) CharacterLiteral(Literal.getValue(), 1188 Literal.isWide(), 1189 type, Tok.getLocation())); 1190} 1191 1192Action::OwningExprResult Sema::ActOnNumericConstant(const Token &Tok) { 1193 // Fast path for a single digit (which is quite common). A single digit 1194 // cannot have a trigraph, escaped newline, radix prefix, or type suffix. 1195 if (Tok.getLength() == 1) { 1196 const char Val = PP.getSpellingOfSingleCharacterNumericConstant(Tok); 1197 unsigned IntSize = Context.Target.getIntWidth(); 1198 return Owned(new (Context) IntegerLiteral(llvm::APInt(IntSize, Val-'0'), 1199 Context.IntTy, Tok.getLocation())); 1200 } 1201 1202 llvm::SmallString<512> IntegerBuffer; 1203 // Add padding so that NumericLiteralParser can overread by one character. 1204 IntegerBuffer.resize(Tok.getLength()+1); 1205 const char *ThisTokBegin = &IntegerBuffer[0]; 1206 1207 // Get the spelling of the token, which eliminates trigraphs, etc. 1208 unsigned ActualLength = PP.getSpelling(Tok, ThisTokBegin); 1209 1210 NumericLiteralParser Literal(ThisTokBegin, ThisTokBegin+ActualLength, 1211 Tok.getLocation(), PP); 1212 if (Literal.hadError) 1213 return ExprError(); 1214 1215 Expr *Res; 1216 1217 if (Literal.isFloatingLiteral()) { 1218 QualType Ty; 1219 if (Literal.isFloat) 1220 Ty = Context.FloatTy; 1221 else if (!Literal.isLong) 1222 Ty = Context.DoubleTy; 1223 else 1224 Ty = Context.LongDoubleTy; 1225 1226 const llvm::fltSemantics &Format = Context.getFloatTypeSemantics(Ty); 1227 1228 // isExact will be set by GetFloatValue(). 1229 bool isExact = false; 1230 llvm::APFloat Val = Literal.GetFloatValue(Format, &isExact); 1231 Res = new (Context) FloatingLiteral(Val, isExact, Ty, Tok.getLocation()); 1232 1233 } else if (!Literal.isIntegerLiteral()) { 1234 return ExprError(); 1235 } else { 1236 QualType Ty; 1237 1238 // long long is a C99 feature. 1239 if (!getLangOptions().C99 && !getLangOptions().CPlusPlus0x && 1240 Literal.isLongLong) 1241 Diag(Tok.getLocation(), diag::ext_longlong); 1242 1243 // Get the value in the widest-possible width. 1244 llvm::APInt ResultVal(Context.Target.getIntMaxTWidth(), 0); 1245 1246 if (Literal.GetIntegerValue(ResultVal)) { 1247 // If this value didn't fit into uintmax_t, warn and force to ull. 1248 Diag(Tok.getLocation(), diag::warn_integer_too_large); 1249 Ty = Context.UnsignedLongLongTy; 1250 assert(Context.getTypeSize(Ty) == ResultVal.getBitWidth() && 1251 "long long is not intmax_t?"); 1252 } else { 1253 // If this value fits into a ULL, try to figure out what else it fits into 1254 // according to the rules of C99 6.4.4.1p5. 1255 1256 // Octal, Hexadecimal, and integers with a U suffix are allowed to 1257 // be an unsigned int. 1258 bool AllowUnsigned = Literal.isUnsigned || Literal.getRadix() != 10; 1259 1260 // Check from smallest to largest, picking the smallest type we can. 1261 unsigned Width = 0; 1262 if (!Literal.isLong && !Literal.isLongLong) { 1263 // Are int/unsigned possibilities? 1264 unsigned IntSize = Context.Target.getIntWidth(); 1265 1266 // Does it fit in a unsigned int? 1267 if (ResultVal.isIntN(IntSize)) { 1268 // Does it fit in a signed int? 1269 if (!Literal.isUnsigned && ResultVal[IntSize-1] == 0) 1270 Ty = Context.IntTy; 1271 else if (AllowUnsigned) 1272 Ty = Context.UnsignedIntTy; 1273 Width = IntSize; 1274 } 1275 } 1276 1277 // Are long/unsigned long possibilities? 1278 if (Ty.isNull() && !Literal.isLongLong) { 1279 unsigned LongSize = Context.Target.getLongWidth(); 1280 1281 // Does it fit in a unsigned long? 1282 if (ResultVal.isIntN(LongSize)) { 1283 // Does it fit in a signed long? 1284 if (!Literal.isUnsigned && ResultVal[LongSize-1] == 0) 1285 Ty = Context.LongTy; 1286 else if (AllowUnsigned) 1287 Ty = Context.UnsignedLongTy; 1288 Width = LongSize; 1289 } 1290 } 1291 1292 // Finally, check long long if needed. 1293 if (Ty.isNull()) { 1294 unsigned LongLongSize = Context.Target.getLongLongWidth(); 1295 1296 // Does it fit in a unsigned long long? 1297 if (ResultVal.isIntN(LongLongSize)) { 1298 // Does it fit in a signed long long? 1299 if (!Literal.isUnsigned && ResultVal[LongLongSize-1] == 0) 1300 Ty = Context.LongLongTy; 1301 else if (AllowUnsigned) 1302 Ty = Context.UnsignedLongLongTy; 1303 Width = LongLongSize; 1304 } 1305 } 1306 1307 // If we still couldn't decide a type, we probably have something that 1308 // does not fit in a signed long long, but has no U suffix. 1309 if (Ty.isNull()) { 1310 Diag(Tok.getLocation(), diag::warn_integer_too_large_for_signed); 1311 Ty = Context.UnsignedLongLongTy; 1312 Width = Context.Target.getLongLongWidth(); 1313 } 1314 1315 if (ResultVal.getBitWidth() != Width) 1316 ResultVal.trunc(Width); 1317 } 1318 Res = new (Context) IntegerLiteral(ResultVal, Ty, Tok.getLocation()); 1319 } 1320 1321 // If this is an imaginary literal, create the ImaginaryLiteral wrapper. 1322 if (Literal.isImaginary) 1323 Res = new (Context) ImaginaryLiteral(Res, 1324 Context.getComplexType(Res->getType())); 1325 1326 return Owned(Res); 1327} 1328 1329Action::OwningExprResult Sema::ActOnParenExpr(SourceLocation L, 1330 SourceLocation R, ExprArg Val) { 1331 Expr *E = Val.takeAs<Expr>(); 1332 assert((E != 0) && "ActOnParenExpr() missing expr"); 1333 return Owned(new (Context) ParenExpr(L, R, E)); 1334} 1335 1336/// The UsualUnaryConversions() function is *not* called by this routine. 1337/// See C99 6.3.2.1p[2-4] for more details. 1338bool Sema::CheckSizeOfAlignOfOperand(QualType exprType, 1339 SourceLocation OpLoc, 1340 const SourceRange &ExprRange, 1341 bool isSizeof) { 1342 if (exprType->isDependentType()) 1343 return false; 1344 1345 // C++ [expr.sizeof]p2: "When applied to a reference or a reference type, 1346 // the result is the size of the referenced type." 1347 // C++ [expr.alignof]p3: "When alignof is applied to a reference type, the 1348 // result shall be the alignment of the referenced type." 1349 if (const ReferenceType *Ref = exprType->getAs<ReferenceType>()) 1350 exprType = Ref->getPointeeType(); 1351 1352 // C99 6.5.3.4p1: 1353 if (exprType->isFunctionType()) { 1354 // alignof(function) is allowed as an extension. 1355 if (isSizeof) 1356 Diag(OpLoc, diag::ext_sizeof_function_type) << ExprRange; 1357 return false; 1358 } 1359 1360 // Allow sizeof(void)/alignof(void) as an extension. 1361 if (exprType->isVoidType()) { 1362 Diag(OpLoc, diag::ext_sizeof_void_type) 1363 << (isSizeof ? "sizeof" : "__alignof") << ExprRange; 1364 return false; 1365 } 1366 1367 if (RequireCompleteType(OpLoc, exprType, 1368 isSizeof ? diag::err_sizeof_incomplete_type : 1369 PDiag(diag::err_alignof_incomplete_type) 1370 << ExprRange)) 1371 return true; 1372 1373 // Reject sizeof(interface) and sizeof(interface<proto>) in 64-bit mode. 1374 if (LangOpts.ObjCNonFragileABI && exprType->isObjCInterfaceType()) { 1375 Diag(OpLoc, diag::err_sizeof_nonfragile_interface) 1376 << exprType << isSizeof << ExprRange; 1377 return true; 1378 } 1379 1380 return false; 1381} 1382 1383bool Sema::CheckAlignOfExpr(Expr *E, SourceLocation OpLoc, 1384 const SourceRange &ExprRange) { 1385 E = E->IgnoreParens(); 1386 1387 // alignof decl is always ok. 1388 if (isa<DeclRefExpr>(E)) 1389 return false; 1390 1391 // Cannot know anything else if the expression is dependent. 1392 if (E->isTypeDependent()) 1393 return false; 1394 1395 if (E->getBitField()) { 1396 Diag(OpLoc, diag::err_sizeof_alignof_bitfield) << 1 << ExprRange; 1397 return true; 1398 } 1399 1400 // Alignment of a field access is always okay, so long as it isn't a 1401 // bit-field. 1402 if (MemberExpr *ME = dyn_cast<MemberExpr>(E)) 1403 if (isa<FieldDecl>(ME->getMemberDecl())) 1404 return false; 1405 1406 return CheckSizeOfAlignOfOperand(E->getType(), OpLoc, ExprRange, false); 1407} 1408 1409/// \brief Build a sizeof or alignof expression given a type operand. 1410Action::OwningExprResult 1411Sema::CreateSizeOfAlignOfExpr(DeclaratorInfo *DInfo, 1412 SourceLocation OpLoc, 1413 bool isSizeOf, SourceRange R) { 1414 if (!DInfo) 1415 return ExprError(); 1416 1417 QualType T = DInfo->getType(); 1418 1419 if (!T->isDependentType() && 1420 CheckSizeOfAlignOfOperand(T, OpLoc, R, isSizeOf)) 1421 return ExprError(); 1422 1423 // C99 6.5.3.4p4: the type (an unsigned integer type) is size_t. 1424 return Owned(new (Context) SizeOfAlignOfExpr(isSizeOf, DInfo, 1425 Context.getSizeType(), OpLoc, 1426 R.getEnd())); 1427} 1428 1429/// \brief Build a sizeof or alignof expression given an expression 1430/// operand. 1431Action::OwningExprResult 1432Sema::CreateSizeOfAlignOfExpr(Expr *E, SourceLocation OpLoc, 1433 bool isSizeOf, SourceRange R) { 1434 // Verify that the operand is valid. 1435 bool isInvalid = false; 1436 if (E->isTypeDependent()) { 1437 // Delay type-checking for type-dependent expressions. 1438 } else if (!isSizeOf) { 1439 isInvalid = CheckAlignOfExpr(E, OpLoc, R); 1440 } else if (E->getBitField()) { // C99 6.5.3.4p1. 1441 Diag(OpLoc, diag::err_sizeof_alignof_bitfield) << 0; 1442 isInvalid = true; 1443 } else { 1444 isInvalid = CheckSizeOfAlignOfOperand(E->getType(), OpLoc, R, true); 1445 } 1446 1447 if (isInvalid) 1448 return ExprError(); 1449 1450 // C99 6.5.3.4p4: the type (an unsigned integer type) is size_t. 1451 return Owned(new (Context) SizeOfAlignOfExpr(isSizeOf, E, 1452 Context.getSizeType(), OpLoc, 1453 R.getEnd())); 1454} 1455 1456/// ActOnSizeOfAlignOfExpr - Handle @c sizeof(type) and @c sizeof @c expr and 1457/// the same for @c alignof and @c __alignof 1458/// Note that the ArgRange is invalid if isType is false. 1459Action::OwningExprResult 1460Sema::ActOnSizeOfAlignOfExpr(SourceLocation OpLoc, bool isSizeof, bool isType, 1461 void *TyOrEx, const SourceRange &ArgRange) { 1462 // If error parsing type, ignore. 1463 if (TyOrEx == 0) return ExprError(); 1464 1465 if (isType) { 1466 DeclaratorInfo *DInfo; 1467 (void) GetTypeFromParser(TyOrEx, &DInfo); 1468 return CreateSizeOfAlignOfExpr(DInfo, OpLoc, isSizeof, ArgRange); 1469 } 1470 1471 Expr *ArgEx = (Expr *)TyOrEx; 1472 Action::OwningExprResult Result 1473 = CreateSizeOfAlignOfExpr(ArgEx, OpLoc, isSizeof, ArgEx->getSourceRange()); 1474 1475 if (Result.isInvalid()) 1476 DeleteExpr(ArgEx); 1477 1478 return move(Result); 1479} 1480 1481QualType Sema::CheckRealImagOperand(Expr *&V, SourceLocation Loc, bool isReal) { 1482 if (V->isTypeDependent()) 1483 return Context.DependentTy; 1484 1485 // These operators return the element type of a complex type. 1486 if (const ComplexType *CT = V->getType()->getAs<ComplexType>()) 1487 return CT->getElementType(); 1488 1489 // Otherwise they pass through real integer and floating point types here. 1490 if (V->getType()->isArithmeticType()) 1491 return V->getType(); 1492 1493 // Reject anything else. 1494 Diag(Loc, diag::err_realimag_invalid_type) << V->getType() 1495 << (isReal ? "__real" : "__imag"); 1496 return QualType(); 1497} 1498 1499 1500 1501Action::OwningExprResult 1502Sema::ActOnPostfixUnaryOp(Scope *S, SourceLocation OpLoc, 1503 tok::TokenKind Kind, ExprArg Input) { 1504 UnaryOperator::Opcode Opc; 1505 switch (Kind) { 1506 default: assert(0 && "Unknown unary op!"); 1507 case tok::plusplus: Opc = UnaryOperator::PostInc; break; 1508 case tok::minusminus: Opc = UnaryOperator::PostDec; break; 1509 } 1510 1511 return BuildUnaryOp(S, OpLoc, Opc, move(Input)); 1512} 1513 1514Action::OwningExprResult 1515Sema::ActOnArraySubscriptExpr(Scope *S, ExprArg Base, SourceLocation LLoc, 1516 ExprArg Idx, SourceLocation RLoc) { 1517 // Since this might be a postfix expression, get rid of ParenListExprs. 1518 Base = MaybeConvertParenListExprToParenExpr(S, move(Base)); 1519 1520 Expr *LHSExp = static_cast<Expr*>(Base.get()), 1521 *RHSExp = static_cast<Expr*>(Idx.get()); 1522 1523 if (getLangOptions().CPlusPlus && 1524 (LHSExp->isTypeDependent() || RHSExp->isTypeDependent())) { 1525 Base.release(); 1526 Idx.release(); 1527 return Owned(new (Context) ArraySubscriptExpr(LHSExp, RHSExp, 1528 Context.DependentTy, RLoc)); 1529 } 1530 1531 if (getLangOptions().CPlusPlus && 1532 (LHSExp->getType()->isRecordType() || 1533 LHSExp->getType()->isEnumeralType() || 1534 RHSExp->getType()->isRecordType() || 1535 RHSExp->getType()->isEnumeralType())) { 1536 return CreateOverloadedArraySubscriptExpr(LLoc, RLoc, move(Base),move(Idx)); 1537 } 1538 1539 return CreateBuiltinArraySubscriptExpr(move(Base), LLoc, move(Idx), RLoc); 1540} 1541 1542 1543Action::OwningExprResult 1544Sema::CreateBuiltinArraySubscriptExpr(ExprArg Base, SourceLocation LLoc, 1545 ExprArg Idx, SourceLocation RLoc) { 1546 Expr *LHSExp = static_cast<Expr*>(Base.get()); 1547 Expr *RHSExp = static_cast<Expr*>(Idx.get()); 1548 1549 // Perform default conversions. 1550 DefaultFunctionArrayConversion(LHSExp); 1551 DefaultFunctionArrayConversion(RHSExp); 1552 1553 QualType LHSTy = LHSExp->getType(), RHSTy = RHSExp->getType(); 1554 1555 // C99 6.5.2.1p2: the expression e1[e2] is by definition precisely equivalent 1556 // to the expression *((e1)+(e2)). This means the array "Base" may actually be 1557 // in the subscript position. As a result, we need to derive the array base 1558 // and index from the expression types. 1559 Expr *BaseExpr, *IndexExpr; 1560 QualType ResultType; 1561 if (LHSTy->isDependentType() || RHSTy->isDependentType()) { 1562 BaseExpr = LHSExp; 1563 IndexExpr = RHSExp; 1564 ResultType = Context.DependentTy; 1565 } else if (const PointerType *PTy = LHSTy->getAs<PointerType>()) { 1566 BaseExpr = LHSExp; 1567 IndexExpr = RHSExp; 1568 ResultType = PTy->getPointeeType(); 1569 } else if (const PointerType *PTy = RHSTy->getAs<PointerType>()) { 1570 // Handle the uncommon case of "123[Ptr]". 1571 BaseExpr = RHSExp; 1572 IndexExpr = LHSExp; 1573 ResultType = PTy->getPointeeType(); 1574 } else if (const ObjCObjectPointerType *PTy = 1575 LHSTy->getAs<ObjCObjectPointerType>()) { 1576 BaseExpr = LHSExp; 1577 IndexExpr = RHSExp; 1578 ResultType = PTy->getPointeeType(); 1579 } else if (const ObjCObjectPointerType *PTy = 1580 RHSTy->getAs<ObjCObjectPointerType>()) { 1581 // Handle the uncommon case of "123[Ptr]". 1582 BaseExpr = RHSExp; 1583 IndexExpr = LHSExp; 1584 ResultType = PTy->getPointeeType(); 1585 } else if (const VectorType *VTy = LHSTy->getAs<VectorType>()) { 1586 BaseExpr = LHSExp; // vectors: V[123] 1587 IndexExpr = RHSExp; 1588 1589 // FIXME: need to deal with const... 1590 ResultType = VTy->getElementType(); 1591 } else if (LHSTy->isArrayType()) { 1592 // If we see an array that wasn't promoted by 1593 // DefaultFunctionArrayConversion, it must be an array that 1594 // wasn't promoted because of the C90 rule that doesn't 1595 // allow promoting non-lvalue arrays. Warn, then 1596 // force the promotion here. 1597 Diag(LHSExp->getLocStart(), diag::ext_subscript_non_lvalue) << 1598 LHSExp->getSourceRange(); 1599 ImpCastExprToType(LHSExp, Context.getArrayDecayedType(LHSTy), 1600 CastExpr::CK_ArrayToPointerDecay); 1601 LHSTy = LHSExp->getType(); 1602 1603 BaseExpr = LHSExp; 1604 IndexExpr = RHSExp; 1605 ResultType = LHSTy->getAs<PointerType>()->getPointeeType(); 1606 } else if (RHSTy->isArrayType()) { 1607 // Same as previous, except for 123[f().a] case 1608 Diag(RHSExp->getLocStart(), diag::ext_subscript_non_lvalue) << 1609 RHSExp->getSourceRange(); 1610 ImpCastExprToType(RHSExp, Context.getArrayDecayedType(RHSTy), 1611 CastExpr::CK_ArrayToPointerDecay); 1612 RHSTy = RHSExp->getType(); 1613 1614 BaseExpr = RHSExp; 1615 IndexExpr = LHSExp; 1616 ResultType = RHSTy->getAs<PointerType>()->getPointeeType(); 1617 } else { 1618 return ExprError(Diag(LLoc, diag::err_typecheck_subscript_value) 1619 << LHSExp->getSourceRange() << RHSExp->getSourceRange()); 1620 } 1621 // C99 6.5.2.1p1 1622 if (!(IndexExpr->getType()->isIntegerType() && 1623 IndexExpr->getType()->isScalarType()) && !IndexExpr->isTypeDependent()) 1624 return ExprError(Diag(LLoc, diag::err_typecheck_subscript_not_integer) 1625 << IndexExpr->getSourceRange()); 1626 1627 if ((IndexExpr->getType()->isSpecificBuiltinType(BuiltinType::Char_S) || 1628 IndexExpr->getType()->isSpecificBuiltinType(BuiltinType::Char_U)) 1629 && !IndexExpr->isTypeDependent()) 1630 Diag(LLoc, diag::warn_subscript_is_char) << IndexExpr->getSourceRange(); 1631 1632 // C99 6.5.2.1p1: "shall have type "pointer to *object* type". Similarly, 1633 // C++ [expr.sub]p1: The type "T" shall be a completely-defined object 1634 // type. Note that Functions are not objects, and that (in C99 parlance) 1635 // incomplete types are not object types. 1636 if (ResultType->isFunctionType()) { 1637 Diag(BaseExpr->getLocStart(), diag::err_subscript_function_type) 1638 << ResultType << BaseExpr->getSourceRange(); 1639 return ExprError(); 1640 } 1641 1642 if (!ResultType->isDependentType() && 1643 RequireCompleteType(LLoc, ResultType, 1644 PDiag(diag::err_subscript_incomplete_type) 1645 << BaseExpr->getSourceRange())) 1646 return ExprError(); 1647 1648 // Diagnose bad cases where we step over interface counts. 1649 if (ResultType->isObjCInterfaceType() && LangOpts.ObjCNonFragileABI) { 1650 Diag(LLoc, diag::err_subscript_nonfragile_interface) 1651 << ResultType << BaseExpr->getSourceRange(); 1652 return ExprError(); 1653 } 1654 1655 Base.release(); 1656 Idx.release(); 1657 return Owned(new (Context) ArraySubscriptExpr(LHSExp, RHSExp, 1658 ResultType, RLoc)); 1659} 1660 1661QualType Sema:: 1662CheckExtVectorComponent(QualType baseType, SourceLocation OpLoc, 1663 const IdentifierInfo *CompName, 1664 SourceLocation CompLoc) { 1665 // FIXME: Share logic with ExtVectorElementExpr::containsDuplicateElements, 1666 // see FIXME there. 1667 // 1668 // FIXME: This logic can be greatly simplified by splitting it along 1669 // halving/not halving and reworking the component checking. 1670 const ExtVectorType *vecType = baseType->getAs<ExtVectorType>(); 1671 1672 // The vector accessor can't exceed the number of elements. 1673 const char *compStr = CompName->getNameStart(); 1674 1675 // This flag determines whether or not the component is one of the four 1676 // special names that indicate a subset of exactly half the elements are 1677 // to be selected. 1678 bool HalvingSwizzle = false; 1679 1680 // This flag determines whether or not CompName has an 's' char prefix, 1681 // indicating that it is a string of hex values to be used as vector indices. 1682 bool HexSwizzle = *compStr == 's' || *compStr == 'S'; 1683 1684 // Check that we've found one of the special components, or that the component 1685 // names must come from the same set. 1686 if (!strcmp(compStr, "hi") || !strcmp(compStr, "lo") || 1687 !strcmp(compStr, "even") || !strcmp(compStr, "odd")) { 1688 HalvingSwizzle = true; 1689 } else if (vecType->getPointAccessorIdx(*compStr) != -1) { 1690 do 1691 compStr++; 1692 while (*compStr && vecType->getPointAccessorIdx(*compStr) != -1); 1693 } else if (HexSwizzle || vecType->getNumericAccessorIdx(*compStr) != -1) { 1694 do 1695 compStr++; 1696 while (*compStr && vecType->getNumericAccessorIdx(*compStr) != -1); 1697 } 1698 1699 if (!HalvingSwizzle && *compStr) { 1700 // We didn't get to the end of the string. This means the component names 1701 // didn't come from the same set *or* we encountered an illegal name. 1702 Diag(OpLoc, diag::err_ext_vector_component_name_illegal) 1703 << std::string(compStr,compStr+1) << SourceRange(CompLoc); 1704 return QualType(); 1705 } 1706 1707 // Ensure no component accessor exceeds the width of the vector type it 1708 // operates on. 1709 if (!HalvingSwizzle) { 1710 compStr = CompName->getNameStart(); 1711 1712 if (HexSwizzle) 1713 compStr++; 1714 1715 while (*compStr) { 1716 if (!vecType->isAccessorWithinNumElements(*compStr++)) { 1717 Diag(OpLoc, diag::err_ext_vector_component_exceeds_length) 1718 << baseType << SourceRange(CompLoc); 1719 return QualType(); 1720 } 1721 } 1722 } 1723 1724 // If this is a halving swizzle, verify that the base type has an even 1725 // number of elements. 1726 if (HalvingSwizzle && (vecType->getNumElements() & 1U)) { 1727 Diag(OpLoc, diag::err_ext_vector_component_requires_even) 1728 << baseType << SourceRange(CompLoc); 1729 return QualType(); 1730 } 1731 1732 // The component accessor looks fine - now we need to compute the actual type. 1733 // The vector type is implied by the component accessor. For example, 1734 // vec4.b is a float, vec4.xy is a vec2, vec4.rgb is a vec3, etc. 1735 // vec4.s0 is a float, vec4.s23 is a vec3, etc. 1736 // vec4.hi, vec4.lo, vec4.e, and vec4.o all return vec2. 1737 unsigned CompSize = HalvingSwizzle ? vecType->getNumElements() / 2 1738 : CompName->getLength(); 1739 if (HexSwizzle) 1740 CompSize--; 1741 1742 if (CompSize == 1) 1743 return vecType->getElementType(); 1744 1745 QualType VT = Context.getExtVectorType(vecType->getElementType(), CompSize); 1746 // Now look up the TypeDefDecl from the vector type. Without this, 1747 // diagostics look bad. We want extended vector types to appear built-in. 1748 for (unsigned i = 0, E = ExtVectorDecls.size(); i != E; ++i) { 1749 if (ExtVectorDecls[i]->getUnderlyingType() == VT) 1750 return Context.getTypedefType(ExtVectorDecls[i]); 1751 } 1752 return VT; // should never get here (a typedef type should always be found). 1753} 1754 1755static Decl *FindGetterNameDeclFromProtocolList(const ObjCProtocolDecl*PDecl, 1756 IdentifierInfo *Member, 1757 const Selector &Sel, 1758 ASTContext &Context) { 1759 1760 if (ObjCPropertyDecl *PD = PDecl->FindPropertyDeclaration(Member)) 1761 return PD; 1762 if (ObjCMethodDecl *OMD = PDecl->getInstanceMethod(Sel)) 1763 return OMD; 1764 1765 for (ObjCProtocolDecl::protocol_iterator I = PDecl->protocol_begin(), 1766 E = PDecl->protocol_end(); I != E; ++I) { 1767 if (Decl *D = FindGetterNameDeclFromProtocolList(*I, Member, Sel, 1768 Context)) 1769 return D; 1770 } 1771 return 0; 1772} 1773 1774static Decl *FindGetterNameDecl(const ObjCObjectPointerType *QIdTy, 1775 IdentifierInfo *Member, 1776 const Selector &Sel, 1777 ASTContext &Context) { 1778 // Check protocols on qualified interfaces. 1779 Decl *GDecl = 0; 1780 for (ObjCObjectPointerType::qual_iterator I = QIdTy->qual_begin(), 1781 E = QIdTy->qual_end(); I != E; ++I) { 1782 if (ObjCPropertyDecl *PD = (*I)->FindPropertyDeclaration(Member)) { 1783 GDecl = PD; 1784 break; 1785 } 1786 // Also must look for a getter name which uses property syntax. 1787 if (ObjCMethodDecl *OMD = (*I)->getInstanceMethod(Sel)) { 1788 GDecl = OMD; 1789 break; 1790 } 1791 } 1792 if (!GDecl) { 1793 for (ObjCObjectPointerType::qual_iterator I = QIdTy->qual_begin(), 1794 E = QIdTy->qual_end(); I != E; ++I) { 1795 // Search in the protocol-qualifier list of current protocol. 1796 GDecl = FindGetterNameDeclFromProtocolList(*I, Member, Sel, Context); 1797 if (GDecl) 1798 return GDecl; 1799 } 1800 } 1801 return GDecl; 1802} 1803 1804Action::OwningExprResult 1805Sema::BuildMemberReferenceExpr(Scope *S, ExprArg Base, SourceLocation OpLoc, 1806 tok::TokenKind OpKind, SourceLocation MemberLoc, 1807 DeclarationName MemberName, 1808 const TemplateArgumentListInfo *ExplicitTemplateArgs, 1809 DeclPtrTy ObjCImpDecl, const CXXScopeSpec *SS, 1810 NamedDecl *FirstQualifierInScope) { 1811 if (SS && SS->isInvalid()) 1812 return ExprError(); 1813 1814 // Since this might be a postfix expression, get rid of ParenListExprs. 1815 Base = MaybeConvertParenListExprToParenExpr(S, move(Base)); 1816 1817 Expr *BaseExpr = Base.takeAs<Expr>(); 1818 assert(BaseExpr && "no base expression"); 1819 1820 // Perform default conversions. 1821 DefaultFunctionArrayConversion(BaseExpr); 1822 1823 QualType BaseType = BaseExpr->getType(); 1824 1825 // If the user is trying to apply -> or . to a function pointer 1826 // type, it's probably because the forgot parentheses to call that 1827 // function. Suggest the addition of those parentheses, build the 1828 // call, and continue on. 1829 if (const PointerType *Ptr = BaseType->getAs<PointerType>()) { 1830 if (const FunctionProtoType *Fun 1831 = Ptr->getPointeeType()->getAs<FunctionProtoType>()) { 1832 QualType ResultTy = Fun->getResultType(); 1833 if (Fun->getNumArgs() == 0 && 1834 ((OpKind == tok::period && ResultTy->isRecordType()) || 1835 (OpKind == tok::arrow && ResultTy->isPointerType() && 1836 ResultTy->getAs<PointerType>()->getPointeeType() 1837 ->isRecordType()))) { 1838 SourceLocation Loc = PP.getLocForEndOfToken(BaseExpr->getLocEnd()); 1839 Diag(Loc, diag::err_member_reference_needs_call) 1840 << QualType(Fun, 0) 1841 << CodeModificationHint::CreateInsertion(Loc, "()"); 1842 1843 OwningExprResult NewBase 1844 = ActOnCallExpr(S, ExprArg(*this, BaseExpr), Loc, 1845 MultiExprArg(*this, 0, 0), 0, Loc); 1846 if (NewBase.isInvalid()) 1847 return move(NewBase); 1848 1849 BaseExpr = NewBase.takeAs<Expr>(); 1850 DefaultFunctionArrayConversion(BaseExpr); 1851 BaseType = BaseExpr->getType(); 1852 } 1853 } 1854 } 1855 1856 // If this is an Objective-C pseudo-builtin and a definition is provided then 1857 // use that. 1858 if (BaseType->isObjCIdType()) { 1859 // We have an 'id' type. Rather than fall through, we check if this 1860 // is a reference to 'isa'. 1861 if (BaseType != Context.ObjCIdRedefinitionType) { 1862 BaseType = Context.ObjCIdRedefinitionType; 1863 ImpCastExprToType(BaseExpr, BaseType, CastExpr::CK_BitCast); 1864 } 1865 } 1866 assert(!BaseType.isNull() && "no type for member expression"); 1867 1868 // Handle properties on ObjC 'Class' types. 1869 if (OpKind == tok::period && BaseType->isObjCClassType()) { 1870 // Also must look for a getter name which uses property syntax. 1871 IdentifierInfo *Member = MemberName.getAsIdentifierInfo(); 1872 Selector Sel = PP.getSelectorTable().getNullarySelector(Member); 1873 if (ObjCMethodDecl *MD = getCurMethodDecl()) { 1874 ObjCInterfaceDecl *IFace = MD->getClassInterface(); 1875 ObjCMethodDecl *Getter; 1876 // FIXME: need to also look locally in the implementation. 1877 if ((Getter = IFace->lookupClassMethod(Sel))) { 1878 // Check the use of this method. 1879 if (DiagnoseUseOfDecl(Getter, MemberLoc)) 1880 return ExprError(); 1881 } 1882 // If we found a getter then this may be a valid dot-reference, we 1883 // will look for the matching setter, in case it is needed. 1884 Selector SetterSel = 1885 SelectorTable::constructSetterName(PP.getIdentifierTable(), 1886 PP.getSelectorTable(), Member); 1887 ObjCMethodDecl *Setter = IFace->lookupClassMethod(SetterSel); 1888 if (!Setter) { 1889 // If this reference is in an @implementation, also check for 'private' 1890 // methods. 1891 Setter = IFace->lookupPrivateInstanceMethod(SetterSel); 1892 } 1893 // Look through local category implementations associated with the class. 1894 if (!Setter) 1895 Setter = IFace->getCategoryClassMethod(SetterSel); 1896 1897 if (Setter && DiagnoseUseOfDecl(Setter, MemberLoc)) 1898 return ExprError(); 1899 1900 if (Getter || Setter) { 1901 QualType PType; 1902 1903 if (Getter) 1904 PType = Getter->getResultType(); 1905 else 1906 // Get the expression type from Setter's incoming parameter. 1907 PType = (*(Setter->param_end() -1))->getType(); 1908 // FIXME: we must check that the setter has property type. 1909 return Owned(new (Context) ObjCImplicitSetterGetterRefExpr(Getter, 1910 PType, 1911 Setter, MemberLoc, BaseExpr)); 1912 } 1913 return ExprError(Diag(MemberLoc, diag::err_property_not_found) 1914 << MemberName << BaseType); 1915 } 1916 } 1917 1918 if (BaseType->isObjCClassType() && 1919 BaseType != Context.ObjCClassRedefinitionType) { 1920 BaseType = Context.ObjCClassRedefinitionType; 1921 ImpCastExprToType(BaseExpr, BaseType, CastExpr::CK_BitCast); 1922 } 1923 1924 // Get the type being accessed in BaseType. If this is an arrow, the BaseExpr 1925 // must have pointer type, and the accessed type is the pointee. 1926 if (OpKind == tok::arrow) { 1927 if (BaseType->isDependentType()) { 1928 NestedNameSpecifier *Qualifier = 0; 1929 if (SS) { 1930 Qualifier = static_cast<NestedNameSpecifier *>(SS->getScopeRep()); 1931 if (!FirstQualifierInScope) 1932 FirstQualifierInScope = FindFirstQualifierInScope(S, Qualifier); 1933 } 1934 1935 return Owned(CXXDependentScopeMemberExpr::Create(Context, BaseExpr, true, 1936 OpLoc, Qualifier, 1937 SS? SS->getRange() : SourceRange(), 1938 FirstQualifierInScope, 1939 MemberName, 1940 MemberLoc, 1941 ExplicitTemplateArgs)); 1942 } 1943 else if (const PointerType *PT = BaseType->getAs<PointerType>()) 1944 BaseType = PT->getPointeeType(); 1945 else if (BaseType->isObjCObjectPointerType()) 1946 ; 1947 else 1948 return ExprError(Diag(MemberLoc, 1949 diag::err_typecheck_member_reference_arrow) 1950 << BaseType << BaseExpr->getSourceRange()); 1951 } else if (BaseType->isDependentType()) { 1952 // Require that the base type isn't a pointer type 1953 // (so we'll report an error for) 1954 // T* t; 1955 // t.f; 1956 // 1957 // In Obj-C++, however, the above expression is valid, since it could be 1958 // accessing the 'f' property if T is an Obj-C interface. The extra check 1959 // allows this, while still reporting an error if T is a struct pointer. 1960 const PointerType *PT = BaseType->getAs<PointerType>(); 1961 1962 if (!PT || (getLangOptions().ObjC1 && 1963 !PT->getPointeeType()->isRecordType())) { 1964 NestedNameSpecifier *Qualifier = 0; 1965 if (SS) { 1966 Qualifier = static_cast<NestedNameSpecifier *>(SS->getScopeRep()); 1967 if (!FirstQualifierInScope) 1968 FirstQualifierInScope = FindFirstQualifierInScope(S, Qualifier); 1969 } 1970 1971 return Owned(CXXDependentScopeMemberExpr::Create(Context, 1972 BaseExpr, false, 1973 OpLoc, 1974 Qualifier, 1975 SS? SS->getRange() : SourceRange(), 1976 FirstQualifierInScope, 1977 MemberName, 1978 MemberLoc, 1979 ExplicitTemplateArgs)); 1980 } 1981 } 1982 1983 // Handle field access to simple records. This also handles access to fields 1984 // of the ObjC 'id' struct. 1985 if (const RecordType *RTy = BaseType->getAs<RecordType>()) { 1986 RecordDecl *RDecl = RTy->getDecl(); 1987 if (RequireCompleteType(OpLoc, BaseType, 1988 PDiag(diag::err_typecheck_incomplete_tag) 1989 << BaseExpr->getSourceRange())) 1990 return ExprError(); 1991 1992 DeclContext *DC = RDecl; 1993 if (SS && SS->isSet()) { 1994 // If the member name was a qualified-id, look into the 1995 // nested-name-specifier. 1996 DC = computeDeclContext(*SS, false); 1997 1998 if (!isa<TypeDecl>(DC)) { 1999 Diag(MemberLoc, diag::err_qualified_member_nonclass) 2000 << DC << SS->getRange(); 2001 return ExprError(); 2002 } 2003 2004 // FIXME: If DC is not computable, we should build a 2005 // CXXDependentScopeMemberExpr. 2006 assert(DC && "Cannot handle non-computable dependent contexts in lookup"); 2007 } 2008 2009 // The record definition is complete, now make sure the member is valid. 2010 LookupResult Result(*this, MemberName, MemberLoc, LookupMemberName); 2011 LookupQualifiedName(Result, DC); 2012 2013 if (Result.empty()) 2014 return ExprError(Diag(MemberLoc, diag::err_no_member) 2015 << MemberName << DC << BaseExpr->getSourceRange()); 2016 if (Result.isAmbiguous()) 2017 return ExprError(); 2018 2019 NamedDecl *MemberDecl = Result.getAsSingleDecl(Context); 2020 2021 if (SS && SS->isSet()) { 2022 TypeDecl* TyD = cast<TypeDecl>(MemberDecl->getDeclContext()); 2023 QualType BaseTypeCanon 2024 = Context.getCanonicalType(BaseType).getUnqualifiedType(); 2025 QualType MemberTypeCanon 2026 = Context.getCanonicalType(Context.getTypeDeclType(TyD)); 2027 2028 if (BaseTypeCanon != MemberTypeCanon && 2029 !IsDerivedFrom(BaseTypeCanon, MemberTypeCanon)) 2030 return ExprError(Diag(SS->getBeginLoc(), 2031 diag::err_not_direct_base_or_virtual) 2032 << MemberTypeCanon << BaseTypeCanon); 2033 } 2034 2035 // If the decl being referenced had an error, return an error for this 2036 // sub-expr without emitting another error, in order to avoid cascading 2037 // error cases. 2038 if (MemberDecl->isInvalidDecl()) 2039 return ExprError(); 2040 2041 bool ShouldCheckUse = true; 2042 if (CXXMethodDecl *MD = dyn_cast<CXXMethodDecl>(MemberDecl)) { 2043 // Don't diagnose the use of a virtual member function unless it's 2044 // explicitly qualified. 2045 if (MD->isVirtual() && (!SS || !SS->isSet())) 2046 ShouldCheckUse = false; 2047 } 2048 2049 // Check the use of this field 2050 if (ShouldCheckUse && DiagnoseUseOfDecl(MemberDecl, MemberLoc)) 2051 return ExprError(); 2052 2053 if (FieldDecl *FD = dyn_cast<FieldDecl>(MemberDecl)) { 2054 // We may have found a field within an anonymous union or struct 2055 // (C++ [class.union]). 2056 if (cast<RecordDecl>(FD->getDeclContext())->isAnonymousStructOrUnion()) 2057 return BuildAnonymousStructUnionMemberReference(MemberLoc, FD, 2058 BaseExpr, OpLoc); 2059 2060 // Figure out the type of the member; see C99 6.5.2.3p3, C++ [expr.ref] 2061 QualType MemberType = FD->getType(); 2062 if (const ReferenceType *Ref = MemberType->getAs<ReferenceType>()) 2063 MemberType = Ref->getPointeeType(); 2064 else { 2065 Qualifiers BaseQuals = BaseType.getQualifiers(); 2066 BaseQuals.removeObjCGCAttr(); 2067 if (FD->isMutable()) BaseQuals.removeConst(); 2068 2069 Qualifiers MemberQuals 2070 = Context.getCanonicalType(MemberType).getQualifiers(); 2071 2072 Qualifiers Combined = BaseQuals + MemberQuals; 2073 if (Combined != MemberQuals) 2074 MemberType = Context.getQualifiedType(MemberType, Combined); 2075 } 2076 2077 MarkDeclarationReferenced(MemberLoc, FD); 2078 if (PerformObjectMemberConversion(BaseExpr, FD)) 2079 return ExprError(); 2080 return Owned(BuildMemberExpr(Context, BaseExpr, OpKind == tok::arrow, SS, 2081 FD, MemberLoc, MemberType)); 2082 } 2083 2084 if (VarDecl *Var = dyn_cast<VarDecl>(MemberDecl)) { 2085 MarkDeclarationReferenced(MemberLoc, MemberDecl); 2086 return Owned(BuildMemberExpr(Context, BaseExpr, OpKind == tok::arrow, SS, 2087 Var, MemberLoc, 2088 Var->getType().getNonReferenceType())); 2089 } 2090 if (FunctionDecl *MemberFn = dyn_cast<FunctionDecl>(MemberDecl)) { 2091 MarkDeclarationReferenced(MemberLoc, MemberDecl); 2092 return Owned(BuildMemberExpr(Context, BaseExpr, OpKind == tok::arrow, SS, 2093 MemberFn, MemberLoc, 2094 MemberFn->getType())); 2095 } 2096 if (FunctionTemplateDecl *FunTmpl 2097 = dyn_cast<FunctionTemplateDecl>(MemberDecl)) { 2098 MarkDeclarationReferenced(MemberLoc, MemberDecl); 2099 2100 if (ExplicitTemplateArgs) 2101 return Owned(MemberExpr::Create(Context, BaseExpr, OpKind == tok::arrow, 2102 (NestedNameSpecifier *)(SS? SS->getScopeRep() : 0), 2103 SS? SS->getRange() : SourceRange(), 2104 FunTmpl, MemberLoc, 2105 ExplicitTemplateArgs, 2106 Context.OverloadTy)); 2107 2108 return Owned(BuildMemberExpr(Context, BaseExpr, OpKind == tok::arrow, SS, 2109 FunTmpl, MemberLoc, 2110 Context.OverloadTy)); 2111 } 2112 if (OverloadedFunctionDecl *Ovl 2113 = dyn_cast<OverloadedFunctionDecl>(MemberDecl)) { 2114 if (ExplicitTemplateArgs) 2115 return Owned(MemberExpr::Create(Context, BaseExpr, OpKind == tok::arrow, 2116 (NestedNameSpecifier *)(SS? SS->getScopeRep() : 0), 2117 SS? SS->getRange() : SourceRange(), 2118 Ovl, MemberLoc, ExplicitTemplateArgs, 2119 Context.OverloadTy)); 2120 2121 return Owned(BuildMemberExpr(Context, BaseExpr, OpKind == tok::arrow, SS, 2122 Ovl, MemberLoc, Context.OverloadTy)); 2123 } 2124 if (EnumConstantDecl *Enum = dyn_cast<EnumConstantDecl>(MemberDecl)) { 2125 MarkDeclarationReferenced(MemberLoc, MemberDecl); 2126 return Owned(BuildMemberExpr(Context, BaseExpr, OpKind == tok::arrow, SS, 2127 Enum, MemberLoc, Enum->getType())); 2128 } 2129 if (isa<TypeDecl>(MemberDecl)) 2130 return ExprError(Diag(MemberLoc,diag::err_typecheck_member_reference_type) 2131 << MemberName << int(OpKind == tok::arrow)); 2132 2133 // We found a declaration kind that we didn't expect. This is a 2134 // generic error message that tells the user that she can't refer 2135 // to this member with '.' or '->'. 2136 return ExprError(Diag(MemberLoc, 2137 diag::err_typecheck_member_reference_unknown) 2138 << MemberName << int(OpKind == tok::arrow)); 2139 } 2140 2141 // Handle pseudo-destructors (C++ [expr.pseudo]). Since anything referring 2142 // into a record type was handled above, any destructor we see here is a 2143 // pseudo-destructor. 2144 if (MemberName.getNameKind() == DeclarationName::CXXDestructorName) { 2145 // C++ [expr.pseudo]p2: 2146 // The left hand side of the dot operator shall be of scalar type. The 2147 // left hand side of the arrow operator shall be of pointer to scalar 2148 // type. 2149 if (!BaseType->isScalarType()) 2150 return Owned(Diag(OpLoc, diag::err_pseudo_dtor_base_not_scalar) 2151 << BaseType << BaseExpr->getSourceRange()); 2152 2153 // [...] The type designated by the pseudo-destructor-name shall be the 2154 // same as the object type. 2155 if (!MemberName.getCXXNameType()->isDependentType() && 2156 !Context.hasSameUnqualifiedType(BaseType, MemberName.getCXXNameType())) 2157 return Owned(Diag(OpLoc, diag::err_pseudo_dtor_type_mismatch) 2158 << BaseType << MemberName.getCXXNameType() 2159 << BaseExpr->getSourceRange() << SourceRange(MemberLoc)); 2160 2161 // [...] Furthermore, the two type-names in a pseudo-destructor-name of 2162 // the form 2163 // 2164 // ::[opt] nested-name-specifier[opt] type-name :: ̃ type-name 2165 // 2166 // shall designate the same scalar type. 2167 // 2168 // FIXME: DPG can't see any way to trigger this particular clause, so it 2169 // isn't checked here. 2170 2171 // FIXME: We've lost the precise spelling of the type by going through 2172 // DeclarationName. Can we do better? 2173 return Owned(new (Context) CXXPseudoDestructorExpr(Context, BaseExpr, 2174 OpKind == tok::arrow, 2175 OpLoc, 2176 (NestedNameSpecifier *)(SS? SS->getScopeRep() : 0), 2177 SS? SS->getRange() : SourceRange(), 2178 MemberName.getCXXNameType(), 2179 MemberLoc)); 2180 } 2181 2182 // Handle access to Objective-C instance variables, such as "Obj->ivar" and 2183 // (*Obj).ivar. 2184 if ((OpKind == tok::arrow && BaseType->isObjCObjectPointerType()) || 2185 (OpKind == tok::period && BaseType->isObjCInterfaceType())) { 2186 const ObjCObjectPointerType *OPT = BaseType->getAs<ObjCObjectPointerType>(); 2187 const ObjCInterfaceType *IFaceT = 2188 OPT ? OPT->getInterfaceType() : BaseType->getAs<ObjCInterfaceType>(); 2189 if (IFaceT) { 2190 IdentifierInfo *Member = MemberName.getAsIdentifierInfo(); 2191 2192 ObjCInterfaceDecl *IDecl = IFaceT->getDecl(); 2193 ObjCInterfaceDecl *ClassDeclared; 2194 ObjCIvarDecl *IV = IDecl->lookupInstanceVariable(Member, ClassDeclared); 2195 2196 if (IV) { 2197 // If the decl being referenced had an error, return an error for this 2198 // sub-expr without emitting another error, in order to avoid cascading 2199 // error cases. 2200 if (IV->isInvalidDecl()) 2201 return ExprError(); 2202 2203 // Check whether we can reference this field. 2204 if (DiagnoseUseOfDecl(IV, MemberLoc)) 2205 return ExprError(); 2206 if (IV->getAccessControl() != ObjCIvarDecl::Public && 2207 IV->getAccessControl() != ObjCIvarDecl::Package) { 2208 ObjCInterfaceDecl *ClassOfMethodDecl = 0; 2209 if (ObjCMethodDecl *MD = getCurMethodDecl()) 2210 ClassOfMethodDecl = MD->getClassInterface(); 2211 else if (ObjCImpDecl && getCurFunctionDecl()) { 2212 // Case of a c-function declared inside an objc implementation. 2213 // FIXME: For a c-style function nested inside an objc implementation 2214 // class, there is no implementation context available, so we pass 2215 // down the context as argument to this routine. Ideally, this context 2216 // need be passed down in the AST node and somehow calculated from the 2217 // AST for a function decl. 2218 Decl *ImplDecl = ObjCImpDecl.getAs<Decl>(); 2219 if (ObjCImplementationDecl *IMPD = 2220 dyn_cast<ObjCImplementationDecl>(ImplDecl)) 2221 ClassOfMethodDecl = IMPD->getClassInterface(); 2222 else if (ObjCCategoryImplDecl* CatImplClass = 2223 dyn_cast<ObjCCategoryImplDecl>(ImplDecl)) 2224 ClassOfMethodDecl = CatImplClass->getClassInterface(); 2225 } 2226 2227 if (IV->getAccessControl() == ObjCIvarDecl::Private) { 2228 if (ClassDeclared != IDecl || 2229 ClassOfMethodDecl != ClassDeclared) 2230 Diag(MemberLoc, diag::error_private_ivar_access) 2231 << IV->getDeclName(); 2232 } else if (!IDecl->isSuperClassOf(ClassOfMethodDecl)) 2233 // @protected 2234 Diag(MemberLoc, diag::error_protected_ivar_access) 2235 << IV->getDeclName(); 2236 } 2237 2238 return Owned(new (Context) ObjCIvarRefExpr(IV, IV->getType(), 2239 MemberLoc, BaseExpr, 2240 OpKind == tok::arrow)); 2241 } 2242 return ExprError(Diag(MemberLoc, diag::err_typecheck_member_reference_ivar) 2243 << IDecl->getDeclName() << MemberName 2244 << BaseExpr->getSourceRange()); 2245 } 2246 } 2247 // Handle properties on 'id' and qualified "id". 2248 if (OpKind == tok::period && (BaseType->isObjCIdType() || 2249 BaseType->isObjCQualifiedIdType())) { 2250 const ObjCObjectPointerType *QIdTy = BaseType->getAs<ObjCObjectPointerType>(); 2251 IdentifierInfo *Member = MemberName.getAsIdentifierInfo(); 2252 2253 // Check protocols on qualified interfaces. 2254 Selector Sel = PP.getSelectorTable().getNullarySelector(Member); 2255 if (Decl *PMDecl = FindGetterNameDecl(QIdTy, Member, Sel, Context)) { 2256 if (ObjCPropertyDecl *PD = dyn_cast<ObjCPropertyDecl>(PMDecl)) { 2257 // Check the use of this declaration 2258 if (DiagnoseUseOfDecl(PD, MemberLoc)) 2259 return ExprError(); 2260 2261 return Owned(new (Context) ObjCPropertyRefExpr(PD, PD->getType(), 2262 MemberLoc, BaseExpr)); 2263 } 2264 if (ObjCMethodDecl *OMD = dyn_cast<ObjCMethodDecl>(PMDecl)) { 2265 // Check the use of this method. 2266 if (DiagnoseUseOfDecl(OMD, MemberLoc)) 2267 return ExprError(); 2268 2269 return Owned(new (Context) ObjCMessageExpr(BaseExpr, Sel, 2270 OMD->getResultType(), 2271 OMD, OpLoc, MemberLoc, 2272 NULL, 0)); 2273 } 2274 } 2275 2276 return ExprError(Diag(MemberLoc, diag::err_property_not_found) 2277 << MemberName << BaseType); 2278 } 2279 // Handle Objective-C property access, which is "Obj.property" where Obj is a 2280 // pointer to a (potentially qualified) interface type. 2281 const ObjCObjectPointerType *OPT; 2282 if (OpKind == tok::period && 2283 (OPT = BaseType->getAsObjCInterfacePointerType())) { 2284 const ObjCInterfaceType *IFaceT = OPT->getInterfaceType(); 2285 ObjCInterfaceDecl *IFace = IFaceT->getDecl(); 2286 IdentifierInfo *Member = MemberName.getAsIdentifierInfo(); 2287 2288 // Search for a declared property first. 2289 if (ObjCPropertyDecl *PD = IFace->FindPropertyDeclaration(Member)) { 2290 // Check whether we can reference this property. 2291 if (DiagnoseUseOfDecl(PD, MemberLoc)) 2292 return ExprError(); 2293 QualType ResTy = PD->getType(); 2294 Selector Sel = PP.getSelectorTable().getNullarySelector(Member); 2295 ObjCMethodDecl *Getter = IFace->lookupInstanceMethod(Sel); 2296 if (DiagnosePropertyAccessorMismatch(PD, Getter, MemberLoc)) 2297 ResTy = Getter->getResultType(); 2298 return Owned(new (Context) ObjCPropertyRefExpr(PD, ResTy, 2299 MemberLoc, BaseExpr)); 2300 } 2301 // Check protocols on qualified interfaces. 2302 for (ObjCObjectPointerType::qual_iterator I = OPT->qual_begin(), 2303 E = OPT->qual_end(); I != E; ++I) 2304 if (ObjCPropertyDecl *PD = (*I)->FindPropertyDeclaration(Member)) { 2305 // Check whether we can reference this property. 2306 if (DiagnoseUseOfDecl(PD, MemberLoc)) 2307 return ExprError(); 2308 2309 return Owned(new (Context) ObjCPropertyRefExpr(PD, PD->getType(), 2310 MemberLoc, BaseExpr)); 2311 } 2312 // If that failed, look for an "implicit" property by seeing if the nullary 2313 // selector is implemented. 2314 2315 // FIXME: The logic for looking up nullary and unary selectors should be 2316 // shared with the code in ActOnInstanceMessage. 2317 2318 Selector Sel = PP.getSelectorTable().getNullarySelector(Member); 2319 ObjCMethodDecl *Getter = IFace->lookupInstanceMethod(Sel); 2320 2321 // If this reference is in an @implementation, check for 'private' methods. 2322 if (!Getter) 2323 Getter = IFace->lookupPrivateInstanceMethod(Sel); 2324 2325 // Look through local category implementations associated with the class. 2326 if (!Getter) 2327 Getter = IFace->getCategoryInstanceMethod(Sel); 2328 if (Getter) { 2329 // Check if we can reference this property. 2330 if (DiagnoseUseOfDecl(Getter, MemberLoc)) 2331 return ExprError(); 2332 } 2333 // If we found a getter then this may be a valid dot-reference, we 2334 // will look for the matching setter, in case it is needed. 2335 Selector SetterSel = 2336 SelectorTable::constructSetterName(PP.getIdentifierTable(), 2337 PP.getSelectorTable(), Member); 2338 ObjCMethodDecl *Setter = IFace->lookupInstanceMethod(SetterSel); 2339 if (!Setter) { 2340 // If this reference is in an @implementation, also check for 'private' 2341 // methods. 2342 Setter = IFace->lookupPrivateInstanceMethod(SetterSel); 2343 } 2344 // Look through local category implementations associated with the class. 2345 if (!Setter) 2346 Setter = IFace->getCategoryInstanceMethod(SetterSel); 2347 2348 if (Setter && DiagnoseUseOfDecl(Setter, MemberLoc)) 2349 return ExprError(); 2350 2351 if (Getter || Setter) { 2352 QualType PType; 2353 2354 if (Getter) 2355 PType = Getter->getResultType(); 2356 else 2357 // Get the expression type from Setter's incoming parameter. 2358 PType = (*(Setter->param_end() -1))->getType(); 2359 // FIXME: we must check that the setter has property type. 2360 return Owned(new (Context) ObjCImplicitSetterGetterRefExpr(Getter, PType, 2361 Setter, MemberLoc, BaseExpr)); 2362 } 2363 return ExprError(Diag(MemberLoc, diag::err_property_not_found) 2364 << MemberName << BaseType); 2365 } 2366 2367 // Handle the following exceptional case (*Obj).isa. 2368 if (OpKind == tok::period && 2369 BaseType->isSpecificBuiltinType(BuiltinType::ObjCId) && 2370 MemberName.getAsIdentifierInfo()->isStr("isa")) 2371 return Owned(new (Context) ObjCIsaExpr(BaseExpr, false, MemberLoc, 2372 Context.getObjCIdType())); 2373 2374 // Handle 'field access' to vectors, such as 'V.xx'. 2375 if (BaseType->isExtVectorType()) { 2376 IdentifierInfo *Member = MemberName.getAsIdentifierInfo(); 2377 QualType ret = CheckExtVectorComponent(BaseType, OpLoc, Member, MemberLoc); 2378 if (ret.isNull()) 2379 return ExprError(); 2380 return Owned(new (Context) ExtVectorElementExpr(ret, BaseExpr, *Member, 2381 MemberLoc)); 2382 } 2383 2384 Diag(MemberLoc, diag::err_typecheck_member_reference_struct_union) 2385 << BaseType << BaseExpr->getSourceRange(); 2386 2387 return ExprError(); 2388} 2389 2390Sema::OwningExprResult Sema::ActOnMemberAccessExpr(Scope *S, ExprArg Base, 2391 SourceLocation OpLoc, 2392 tok::TokenKind OpKind, 2393 const CXXScopeSpec &SS, 2394 UnqualifiedId &Member, 2395 DeclPtrTy ObjCImpDecl, 2396 bool HasTrailingLParen) { 2397 if (Member.getKind() == UnqualifiedId::IK_TemplateId) { 2398 TemplateName Template 2399 = TemplateName::getFromVoidPointer(Member.TemplateId->Template); 2400 2401 // FIXME: We're going to end up looking up the template based on its name, 2402 // twice! 2403 DeclarationName Name; 2404 if (TemplateDecl *ActualTemplate = Template.getAsTemplateDecl()) 2405 Name = ActualTemplate->getDeclName(); 2406 else if (OverloadedFunctionDecl *Ovl = Template.getAsOverloadedFunctionDecl()) 2407 Name = Ovl->getDeclName(); 2408 else { 2409 DependentTemplateName *DTN = Template.getAsDependentTemplateName(); 2410 if (DTN->isIdentifier()) 2411 Name = DTN->getIdentifier(); 2412 else 2413 Name = Context.DeclarationNames.getCXXOperatorName(DTN->getOperator()); 2414 } 2415 2416 // Translate the parser's template argument list in our AST format. 2417 ASTTemplateArgsPtr TemplateArgsPtr(*this, 2418 Member.TemplateId->getTemplateArgs(), 2419 Member.TemplateId->NumArgs); 2420 2421 TemplateArgumentListInfo TemplateArgs; 2422 TemplateArgs.setLAngleLoc(Member.TemplateId->LAngleLoc); 2423 TemplateArgs.setRAngleLoc(Member.TemplateId->RAngleLoc); 2424 translateTemplateArguments(TemplateArgsPtr, TemplateArgs); 2425 TemplateArgsPtr.release(); 2426 2427 // Do we have the save the actual template name? We might need it... 2428 return BuildMemberReferenceExpr(S, move(Base), OpLoc, OpKind, 2429 Member.TemplateId->TemplateNameLoc, 2430 Name, &TemplateArgs, DeclPtrTy(), 2431 &SS); 2432 } 2433 2434 // FIXME: We lose a lot of source information by mapping directly to the 2435 // DeclarationName. 2436 OwningExprResult Result 2437 = BuildMemberReferenceExpr(S, move(Base), OpLoc, OpKind, 2438 Member.getSourceRange().getBegin(), 2439 GetNameFromUnqualifiedId(Member), 2440 ObjCImpDecl, &SS); 2441 2442 if (Result.isInvalid() || HasTrailingLParen || 2443 Member.getKind() != UnqualifiedId::IK_DestructorName) 2444 return move(Result); 2445 2446 // The only way a reference to a destructor can be used is to 2447 // immediately call them. Since the next token is not a '(', produce a 2448 // diagnostic and build the call now. 2449 Expr *E = (Expr *)Result.get(); 2450 SourceLocation ExpectedLParenLoc 2451 = PP.getLocForEndOfToken(Member.getSourceRange().getEnd()); 2452 Diag(E->getLocStart(), diag::err_dtor_expr_without_call) 2453 << isa<CXXPseudoDestructorExpr>(E) 2454 << CodeModificationHint::CreateInsertion(ExpectedLParenLoc, "()"); 2455 2456 return ActOnCallExpr(0, move(Result), ExpectedLParenLoc, 2457 MultiExprArg(*this, 0, 0), 0, ExpectedLParenLoc); 2458} 2459 2460Sema::OwningExprResult Sema::BuildCXXDefaultArgExpr(SourceLocation CallLoc, 2461 FunctionDecl *FD, 2462 ParmVarDecl *Param) { 2463 if (Param->hasUnparsedDefaultArg()) { 2464 Diag (CallLoc, 2465 diag::err_use_of_default_argument_to_function_declared_later) << 2466 FD << cast<CXXRecordDecl>(FD->getDeclContext())->getDeclName(); 2467 Diag(UnparsedDefaultArgLocs[Param], 2468 diag::note_default_argument_declared_here); 2469 } else { 2470 if (Param->hasUninstantiatedDefaultArg()) { 2471 Expr *UninstExpr = Param->getUninstantiatedDefaultArg(); 2472 2473 // Instantiate the expression. 2474 MultiLevelTemplateArgumentList ArgList = getTemplateInstantiationArgs(FD); 2475 2476 InstantiatingTemplate Inst(*this, CallLoc, Param, 2477 ArgList.getInnermost().getFlatArgumentList(), 2478 ArgList.getInnermost().flat_size()); 2479 2480 OwningExprResult Result = SubstExpr(UninstExpr, ArgList); 2481 if (Result.isInvalid()) 2482 return ExprError(); 2483 2484 if (SetParamDefaultArgument(Param, move(Result), 2485 /*FIXME:EqualLoc*/ 2486 UninstExpr->getSourceRange().getBegin())) 2487 return ExprError(); 2488 } 2489 2490 Expr *DefaultExpr = Param->getDefaultArg(); 2491 2492 // If the default expression creates temporaries, we need to 2493 // push them to the current stack of expression temporaries so they'll 2494 // be properly destroyed. 2495 if (CXXExprWithTemporaries *E 2496 = dyn_cast_or_null<CXXExprWithTemporaries>(DefaultExpr)) { 2497 assert(!E->shouldDestroyTemporaries() && 2498 "Can't destroy temporaries in a default argument expr!"); 2499 for (unsigned I = 0, N = E->getNumTemporaries(); I != N; ++I) 2500 ExprTemporaries.push_back(E->getTemporary(I)); 2501 } 2502 } 2503 2504 // We already type-checked the argument, so we know it works. 2505 return Owned(CXXDefaultArgExpr::Create(Context, Param)); 2506} 2507 2508/// ConvertArgumentsForCall - Converts the arguments specified in 2509/// Args/NumArgs to the parameter types of the function FDecl with 2510/// function prototype Proto. Call is the call expression itself, and 2511/// Fn is the function expression. For a C++ member function, this 2512/// routine does not attempt to convert the object argument. Returns 2513/// true if the call is ill-formed. 2514bool 2515Sema::ConvertArgumentsForCall(CallExpr *Call, Expr *Fn, 2516 FunctionDecl *FDecl, 2517 const FunctionProtoType *Proto, 2518 Expr **Args, unsigned NumArgs, 2519 SourceLocation RParenLoc) { 2520 // C99 6.5.2.2p7 - the arguments are implicitly converted, as if by 2521 // assignment, to the types of the corresponding parameter, ... 2522 unsigned NumArgsInProto = Proto->getNumArgs(); 2523 bool Invalid = false; 2524 2525 // If too few arguments are available (and we don't have default 2526 // arguments for the remaining parameters), don't make the call. 2527 if (NumArgs < NumArgsInProto) { 2528 if (!FDecl || NumArgs < FDecl->getMinRequiredArguments()) 2529 return Diag(RParenLoc, diag::err_typecheck_call_too_few_args) 2530 << Fn->getType()->isBlockPointerType() << Fn->getSourceRange(); 2531 Call->setNumArgs(Context, NumArgsInProto); 2532 } 2533 2534 // If too many are passed and not variadic, error on the extras and drop 2535 // them. 2536 if (NumArgs > NumArgsInProto) { 2537 if (!Proto->isVariadic()) { 2538 Diag(Args[NumArgsInProto]->getLocStart(), 2539 diag::err_typecheck_call_too_many_args) 2540 << Fn->getType()->isBlockPointerType() << Fn->getSourceRange() 2541 << SourceRange(Args[NumArgsInProto]->getLocStart(), 2542 Args[NumArgs-1]->getLocEnd()); 2543 // This deletes the extra arguments. 2544 Call->setNumArgs(Context, NumArgsInProto); 2545 return true; 2546 } 2547 } 2548 llvm::SmallVector<Expr *, 8> AllArgs; 2549 Invalid = GatherArgumentsForCall(Call->getSourceRange().getBegin(), FDecl, 2550 Proto, 0, Args, NumArgs, AllArgs, Fn); 2551 if (Invalid) 2552 return true; 2553 unsigned TotalNumArgs = AllArgs.size(); 2554 for (unsigned i = 0; i < TotalNumArgs; ++i) 2555 Call->setArg(i, AllArgs[i]); 2556 2557 return false; 2558} 2559 2560bool Sema::GatherArgumentsForCall(SourceLocation CallLoc, 2561 FunctionDecl *FDecl, 2562 const FunctionProtoType *Proto, 2563 unsigned FirstProtoArg, 2564 Expr **Args, unsigned NumArgs, 2565 llvm::SmallVector<Expr *, 8> &AllArgs, 2566 Expr *Fn) { 2567 unsigned NumArgsInProto = Proto->getNumArgs(); 2568 unsigned NumArgsToCheck = NumArgs; 2569 bool Invalid = false; 2570 if (NumArgs != NumArgsInProto) 2571 // Use default arguments for missing arguments 2572 NumArgsToCheck = NumArgsInProto; 2573 unsigned ArgIx = 0; 2574 // Continue to check argument types (even if we have too few/many args). 2575 for (unsigned i = FirstProtoArg; i != NumArgsToCheck; i++) { 2576 QualType ProtoArgType = Proto->getArgType(i); 2577 2578 Expr *Arg; 2579 if (ArgIx < NumArgs) { 2580 Arg = Args[ArgIx++]; 2581 2582 if (RequireCompleteType(Arg->getSourceRange().getBegin(), 2583 ProtoArgType, 2584 PDiag(diag::err_call_incomplete_argument) 2585 << Arg->getSourceRange())) 2586 return true; 2587 2588 // Pass the argument. 2589 if (PerformCopyInitialization(Arg, ProtoArgType, "passing")) 2590 return true; 2591 2592 if (!ProtoArgType->isReferenceType()) 2593 Arg = MaybeBindToTemporary(Arg).takeAs<Expr>(); 2594 } else { 2595 ParmVarDecl *Param = FDecl->getParamDecl(i); 2596 2597 OwningExprResult ArgExpr = 2598 BuildCXXDefaultArgExpr(CallLoc, FDecl, Param); 2599 if (ArgExpr.isInvalid()) 2600 return true; 2601 2602 Arg = ArgExpr.takeAs<Expr>(); 2603 } 2604 AllArgs.push_back(Arg); 2605 } 2606 2607 // If this is a variadic call, handle args passed through "...". 2608 if (Proto->isVariadic()) { 2609 VariadicCallType CallType = VariadicFunction; 2610 if (Fn) { 2611 if (Fn->getType()->isBlockPointerType()) 2612 CallType = VariadicBlock; // Block 2613 else if (isa<MemberExpr>(Fn)) 2614 CallType = VariadicMethod; 2615 } 2616 // Promote the arguments (C99 6.5.2.2p7). 2617 for (unsigned i = ArgIx; i < NumArgs; i++) { 2618 Expr *Arg = Args[i]; 2619 Invalid |= DefaultVariadicArgumentPromotion(Arg, CallType); 2620 AllArgs.push_back(Arg); 2621 } 2622 } 2623 return Invalid; 2624} 2625 2626/// \brief "Deconstruct" the function argument of a call expression to find 2627/// the underlying declaration (if any), the name of the called function, 2628/// whether argument-dependent lookup is available, whether it has explicit 2629/// template arguments, etc. 2630void Sema::DeconstructCallFunction(Expr *FnExpr, 2631 llvm::SmallVectorImpl<NamedDecl*> &Fns, 2632 DeclarationName &Name, 2633 NestedNameSpecifier *&Qualifier, 2634 SourceRange &QualifierRange, 2635 bool &ArgumentDependentLookup, 2636 bool &Overloaded, 2637 bool &HasExplicitTemplateArguments, 2638 TemplateArgumentListInfo &ExplicitTemplateArgs) { 2639 // Set defaults for all of the output parameters. 2640 Name = DeclarationName(); 2641 Qualifier = 0; 2642 QualifierRange = SourceRange(); 2643 ArgumentDependentLookup = getLangOptions().CPlusPlus; 2644 Overloaded = false; 2645 HasExplicitTemplateArguments = false; 2646 2647 // Most of the explicit tracking of ArgumentDependentLookup in this 2648 // function can disappear when we handle unresolved 2649 // TemplateIdRefExprs properly. 2650 2651 // If we're directly calling a function, get the appropriate declaration. 2652 // Also, in C++, keep track of whether we should perform argument-dependent 2653 // lookup and whether there were any explicitly-specified template arguments. 2654 while (true) { 2655 if (ImplicitCastExpr *IcExpr = dyn_cast<ImplicitCastExpr>(FnExpr)) 2656 FnExpr = IcExpr->getSubExpr(); 2657 else if (ParenExpr *PExpr = dyn_cast<ParenExpr>(FnExpr)) { 2658 // Parentheses around a function disable ADL 2659 // (C++0x [basic.lookup.argdep]p1). 2660 ArgumentDependentLookup = false; 2661 FnExpr = PExpr->getSubExpr(); 2662 } else if (isa<UnaryOperator>(FnExpr) && 2663 cast<UnaryOperator>(FnExpr)->getOpcode() 2664 == UnaryOperator::AddrOf) { 2665 FnExpr = cast<UnaryOperator>(FnExpr)->getSubExpr(); 2666 } else if (DeclRefExpr *DRExpr = dyn_cast<DeclRefExpr>(FnExpr)) { 2667 Fns.push_back(cast<NamedDecl>(DRExpr->getDecl())); 2668 ArgumentDependentLookup = false; 2669 if ((Qualifier = DRExpr->getQualifier())) 2670 QualifierRange = DRExpr->getQualifierRange(); 2671 break; 2672 } else if (UnresolvedLookupExpr *UnresLookup 2673 = dyn_cast<UnresolvedLookupExpr>(FnExpr)) { 2674 Name = UnresLookup->getName(); 2675 Fns.append(UnresLookup->decls_begin(), UnresLookup->decls_end()); 2676 ArgumentDependentLookup = UnresLookup->requiresADL(); 2677 Overloaded = UnresLookup->isOverloaded(); 2678 if ((Qualifier = UnresLookup->getQualifier())) 2679 QualifierRange = UnresLookup->getQualifierRange(); 2680 break; 2681 } else if (TemplateIdRefExpr *TemplateIdRef 2682 = dyn_cast<TemplateIdRefExpr>(FnExpr)) { 2683 if (NamedDecl *Function 2684 = TemplateIdRef->getTemplateName().getAsTemplateDecl()) { 2685 Name = Function->getDeclName(); 2686 Fns.push_back(Function); 2687 } 2688 else { 2689 OverloadedFunctionDecl *Overload 2690 = TemplateIdRef->getTemplateName().getAsOverloadedFunctionDecl(); 2691 Name = Overload->getDeclName(); 2692 Fns.append(Overload->function_begin(), Overload->function_end()); 2693 } 2694 Overloaded = true; 2695 HasExplicitTemplateArguments = true; 2696 TemplateIdRef->copyTemplateArgumentsInto(ExplicitTemplateArgs); 2697 2698 // C++ [temp.arg.explicit]p6: 2699 // [Note: For simple function names, argument dependent lookup (3.4.2) 2700 // applies even when the function name is not visible within the 2701 // scope of the call. This is because the call still has the syntactic 2702 // form of a function call (3.4.1). But when a function template with 2703 // explicit template arguments is used, the call does not have the 2704 // correct syntactic form unless there is a function template with 2705 // that name visible at the point of the call. If no such name is 2706 // visible, the call is not syntactically well-formed and 2707 // argument-dependent lookup does not apply. If some such name is 2708 // visible, argument dependent lookup applies and additional function 2709 // templates may be found in other namespaces. 2710 // 2711 // The summary of this paragraph is that, if we get to this point and the 2712 // template-id was not a qualified name, then argument-dependent lookup 2713 // is still possible. 2714 if ((Qualifier = TemplateIdRef->getQualifier())) { 2715 ArgumentDependentLookup = false; 2716 QualifierRange = TemplateIdRef->getQualifierRange(); 2717 } 2718 break; 2719 } else { 2720 // Any kind of name that does not refer to a declaration (or 2721 // set of declarations) disables ADL (C++0x [basic.lookup.argdep]p3). 2722 ArgumentDependentLookup = false; 2723 break; 2724 } 2725 } 2726} 2727 2728/// ActOnCallExpr - Handle a call to Fn with the specified array of arguments. 2729/// This provides the location of the left/right parens and a list of comma 2730/// locations. 2731Action::OwningExprResult 2732Sema::ActOnCallExpr(Scope *S, ExprArg fn, SourceLocation LParenLoc, 2733 MultiExprArg args, 2734 SourceLocation *CommaLocs, SourceLocation RParenLoc) { 2735 unsigned NumArgs = args.size(); 2736 2737 // Since this might be a postfix expression, get rid of ParenListExprs. 2738 fn = MaybeConvertParenListExprToParenExpr(S, move(fn)); 2739 2740 Expr *Fn = fn.takeAs<Expr>(); 2741 Expr **Args = reinterpret_cast<Expr**>(args.release()); 2742 assert(Fn && "no function call expression"); 2743 2744 if (getLangOptions().CPlusPlus) { 2745 // If this is a pseudo-destructor expression, build the call immediately. 2746 if (isa<CXXPseudoDestructorExpr>(Fn)) { 2747 if (NumArgs > 0) { 2748 // Pseudo-destructor calls should not have any arguments. 2749 Diag(Fn->getLocStart(), diag::err_pseudo_dtor_call_with_args) 2750 << CodeModificationHint::CreateRemoval( 2751 SourceRange(Args[0]->getLocStart(), 2752 Args[NumArgs-1]->getLocEnd())); 2753 2754 for (unsigned I = 0; I != NumArgs; ++I) 2755 Args[I]->Destroy(Context); 2756 2757 NumArgs = 0; 2758 } 2759 2760 return Owned(new (Context) CallExpr(Context, Fn, 0, 0, Context.VoidTy, 2761 RParenLoc)); 2762 } 2763 2764 // Determine whether this is a dependent call inside a C++ template, 2765 // in which case we won't do any semantic analysis now. 2766 // FIXME: Will need to cache the results of name lookup (including ADL) in 2767 // Fn. 2768 bool Dependent = false; 2769 if (Fn->isTypeDependent()) 2770 Dependent = true; 2771 else if (Expr::hasAnyTypeDependentArguments(Args, NumArgs)) 2772 Dependent = true; 2773 2774 if (Dependent) 2775 return Owned(new (Context) CallExpr(Context, Fn, Args, NumArgs, 2776 Context.DependentTy, RParenLoc)); 2777 2778 // Determine whether this is a call to an object (C++ [over.call.object]). 2779 if (Fn->getType()->isRecordType()) 2780 return Owned(BuildCallToObjectOfClassType(S, Fn, LParenLoc, Args, NumArgs, 2781 CommaLocs, RParenLoc)); 2782 2783 // Determine whether this is a call to a member function. 2784 if (MemberExpr *MemExpr = dyn_cast<MemberExpr>(Fn->IgnoreParens())) { 2785 NamedDecl *MemDecl = MemExpr->getMemberDecl(); 2786 if (isa<OverloadedFunctionDecl>(MemDecl) || 2787 isa<CXXMethodDecl>(MemDecl) || 2788 (isa<FunctionTemplateDecl>(MemDecl) && 2789 isa<CXXMethodDecl>( 2790 cast<FunctionTemplateDecl>(MemDecl)->getTemplatedDecl()))) 2791 return Owned(BuildCallToMemberFunction(S, Fn, LParenLoc, Args, NumArgs, 2792 CommaLocs, RParenLoc)); 2793 } 2794 2795 // Determine whether this is a call to a pointer-to-member function. 2796 if (BinaryOperator *BO = dyn_cast<BinaryOperator>(Fn->IgnoreParens())) { 2797 if (BO->getOpcode() == BinaryOperator::PtrMemD || 2798 BO->getOpcode() == BinaryOperator::PtrMemI) { 2799 if (const FunctionProtoType *FPT = 2800 dyn_cast<FunctionProtoType>(BO->getType())) { 2801 QualType ResultTy = FPT->getResultType().getNonReferenceType(); 2802 2803 ExprOwningPtr<CXXMemberCallExpr> 2804 TheCall(this, new (Context) CXXMemberCallExpr(Context, BO, Args, 2805 NumArgs, ResultTy, 2806 RParenLoc)); 2807 2808 if (CheckCallReturnType(FPT->getResultType(), 2809 BO->getRHS()->getSourceRange().getBegin(), 2810 TheCall.get(), 0)) 2811 return ExprError(); 2812 2813 if (ConvertArgumentsForCall(&*TheCall, BO, 0, FPT, Args, NumArgs, 2814 RParenLoc)) 2815 return ExprError(); 2816 2817 return Owned(MaybeBindToTemporary(TheCall.release()).release()); 2818 } 2819 return ExprError(Diag(Fn->getLocStart(), 2820 diag::err_typecheck_call_not_function) 2821 << Fn->getType() << Fn->getSourceRange()); 2822 } 2823 } 2824 } 2825 2826 // If we're directly calling a function, get the appropriate declaration. 2827 // Also, in C++, keep track of whether we should perform argument-dependent 2828 // lookup and whether there were any explicitly-specified template arguments. 2829 llvm::SmallVector<NamedDecl*,8> Fns; 2830 DeclarationName UnqualifiedName; 2831 bool Overloaded; 2832 bool ADL; 2833 bool HasExplicitTemplateArgs = 0; 2834 TemplateArgumentListInfo ExplicitTemplateArgs; 2835 NestedNameSpecifier *Qualifier = 0; 2836 SourceRange QualifierRange; 2837 DeconstructCallFunction(Fn, Fns, UnqualifiedName, Qualifier, QualifierRange, 2838 ADL, Overloaded, HasExplicitTemplateArgs, 2839 ExplicitTemplateArgs); 2840 2841 NamedDecl *NDecl; // the specific declaration we're calling, if applicable 2842 FunctionDecl *FDecl; // same, if it's known to be a function 2843 2844 if (Overloaded || ADL) { 2845#ifndef NDEBUG 2846 if (ADL) { 2847 // To do ADL, we must have found an unqualified name. 2848 assert(UnqualifiedName && "found no unqualified name for ADL"); 2849 2850 // We don't perform ADL for implicit declarations of builtins. 2851 // Verify that this was correctly set up. 2852 if (Fns.size() == 1 && (FDecl = dyn_cast<FunctionDecl>(Fns[0])) && 2853 FDecl->getBuiltinID() && FDecl->isImplicit()) 2854 assert(0 && "performing ADL for builtin"); 2855 2856 // We don't perform ADL in C. 2857 assert(getLangOptions().CPlusPlus && "ADL enabled in C"); 2858 } 2859 2860 if (Overloaded) { 2861 // To be overloaded, we must either have multiple functions or 2862 // at least one function template (which is effectively an 2863 // infinite set of functions). 2864 assert((Fns.size() > 1 || 2865 (Fns.size() == 1 && 2866 isa<FunctionTemplateDecl>(Fns[0]->getUnderlyingDecl()))) 2867 && "unrecognized overload situation"); 2868 } 2869#endif 2870 2871 FDecl = ResolveOverloadedCallFn(Fn, Fns, UnqualifiedName, 2872 (HasExplicitTemplateArgs ? &ExplicitTemplateArgs : 0), 2873 LParenLoc, Args, NumArgs, CommaLocs, 2874 RParenLoc, ADL); 2875 if (!FDecl) 2876 return ExprError(); 2877 2878 Fn = FixOverloadedFunctionReference(Fn, FDecl); 2879 2880 NDecl = FDecl; 2881 } else { 2882 assert(Fns.size() <= 1 && "overloaded without Overloaded flag"); 2883 if (Fns.empty()) 2884 NDecl = FDecl = 0; 2885 else { 2886 NDecl = Fns[0]; 2887 FDecl = dyn_cast<FunctionDecl>(NDecl); 2888 } 2889 } 2890 2891 // Promote the function operand. 2892 UsualUnaryConversions(Fn); 2893 2894 // Make the call expr early, before semantic checks. This guarantees cleanup 2895 // of arguments and function on error. 2896 ExprOwningPtr<CallExpr> TheCall(this, new (Context) CallExpr(Context, Fn, 2897 Args, NumArgs, 2898 Context.BoolTy, 2899 RParenLoc)); 2900 2901 const FunctionType *FuncT; 2902 if (!Fn->getType()->isBlockPointerType()) { 2903 // C99 6.5.2.2p1 - "The expression that denotes the called function shall 2904 // have type pointer to function". 2905 const PointerType *PT = Fn->getType()->getAs<PointerType>(); 2906 if (PT == 0) 2907 return ExprError(Diag(LParenLoc, diag::err_typecheck_call_not_function) 2908 << Fn->getType() << Fn->getSourceRange()); 2909 FuncT = PT->getPointeeType()->getAs<FunctionType>(); 2910 } else { // This is a block call. 2911 FuncT = Fn->getType()->getAs<BlockPointerType>()->getPointeeType()-> 2912 getAs<FunctionType>(); 2913 } 2914 if (FuncT == 0) 2915 return ExprError(Diag(LParenLoc, diag::err_typecheck_call_not_function) 2916 << Fn->getType() << Fn->getSourceRange()); 2917 2918 // Check for a valid return type 2919 if (CheckCallReturnType(FuncT->getResultType(), 2920 Fn->getSourceRange().getBegin(), TheCall.get(), 2921 FDecl)) 2922 return ExprError(); 2923 2924 // We know the result type of the call, set it. 2925 TheCall->setType(FuncT->getResultType().getNonReferenceType()); 2926 2927 if (const FunctionProtoType *Proto = dyn_cast<FunctionProtoType>(FuncT)) { 2928 if (ConvertArgumentsForCall(&*TheCall, Fn, FDecl, Proto, Args, NumArgs, 2929 RParenLoc)) 2930 return ExprError(); 2931 } else { 2932 assert(isa<FunctionNoProtoType>(FuncT) && "Unknown FunctionType!"); 2933 2934 if (FDecl) { 2935 // Check if we have too few/too many template arguments, based 2936 // on our knowledge of the function definition. 2937 const FunctionDecl *Def = 0; 2938 if (FDecl->getBody(Def) && NumArgs != Def->param_size()) { 2939 const FunctionProtoType *Proto = 2940 Def->getType()->getAs<FunctionProtoType>(); 2941 if (!Proto || !(Proto->isVariadic() && NumArgs >= Def->param_size())) { 2942 Diag(RParenLoc, diag::warn_call_wrong_number_of_arguments) 2943 << (NumArgs > Def->param_size()) << FDecl << Fn->getSourceRange(); 2944 } 2945 } 2946 } 2947 2948 // Promote the arguments (C99 6.5.2.2p6). 2949 for (unsigned i = 0; i != NumArgs; i++) { 2950 Expr *Arg = Args[i]; 2951 DefaultArgumentPromotion(Arg); 2952 if (RequireCompleteType(Arg->getSourceRange().getBegin(), 2953 Arg->getType(), 2954 PDiag(diag::err_call_incomplete_argument) 2955 << Arg->getSourceRange())) 2956 return ExprError(); 2957 TheCall->setArg(i, Arg); 2958 } 2959 } 2960 2961 if (CXXMethodDecl *Method = dyn_cast_or_null<CXXMethodDecl>(FDecl)) 2962 if (!Method->isStatic()) 2963 return ExprError(Diag(LParenLoc, diag::err_member_call_without_object) 2964 << Fn->getSourceRange()); 2965 2966 // Check for sentinels 2967 if (NDecl) 2968 DiagnoseSentinelCalls(NDecl, LParenLoc, Args, NumArgs); 2969 2970 // Do special checking on direct calls to functions. 2971 if (FDecl) { 2972 if (CheckFunctionCall(FDecl, TheCall.get())) 2973 return ExprError(); 2974 2975 if (unsigned BuiltinID = FDecl->getBuiltinID()) 2976 return CheckBuiltinFunctionCall(BuiltinID, TheCall.take()); 2977 } else if (NDecl) { 2978 if (CheckBlockCall(NDecl, TheCall.get())) 2979 return ExprError(); 2980 } 2981 2982 return MaybeBindToTemporary(TheCall.take()); 2983} 2984 2985Action::OwningExprResult 2986Sema::ActOnCompoundLiteral(SourceLocation LParenLoc, TypeTy *Ty, 2987 SourceLocation RParenLoc, ExprArg InitExpr) { 2988 assert((Ty != 0) && "ActOnCompoundLiteral(): missing type"); 2989 //FIXME: Preserve type source info. 2990 QualType literalType = GetTypeFromParser(Ty); 2991 // FIXME: put back this assert when initializers are worked out. 2992 //assert((InitExpr != 0) && "ActOnCompoundLiteral(): missing expression"); 2993 Expr *literalExpr = static_cast<Expr*>(InitExpr.get()); 2994 2995 if (literalType->isArrayType()) { 2996 if (literalType->isVariableArrayType()) 2997 return ExprError(Diag(LParenLoc, diag::err_variable_object_no_init) 2998 << SourceRange(LParenLoc, literalExpr->getSourceRange().getEnd())); 2999 } else if (!literalType->isDependentType() && 3000 RequireCompleteType(LParenLoc, literalType, 3001 PDiag(diag::err_typecheck_decl_incomplete_type) 3002 << SourceRange(LParenLoc, 3003 literalExpr->getSourceRange().getEnd()))) 3004 return ExprError(); 3005 3006 if (CheckInitializerTypes(literalExpr, literalType, LParenLoc, 3007 DeclarationName(), /*FIXME:DirectInit=*/false)) 3008 return ExprError(); 3009 3010 bool isFileScope = getCurFunctionOrMethodDecl() == 0; 3011 if (isFileScope) { // 6.5.2.5p3 3012 if (CheckForConstantInitializer(literalExpr, literalType)) 3013 return ExprError(); 3014 } 3015 InitExpr.release(); 3016 return Owned(new (Context) CompoundLiteralExpr(LParenLoc, literalType, 3017 literalExpr, isFileScope)); 3018} 3019 3020Action::OwningExprResult 3021Sema::ActOnInitList(SourceLocation LBraceLoc, MultiExprArg initlist, 3022 SourceLocation RBraceLoc) { 3023 unsigned NumInit = initlist.size(); 3024 Expr **InitList = reinterpret_cast<Expr**>(initlist.release()); 3025 3026 // Semantic analysis for initializers is done by ActOnDeclarator() and 3027 // CheckInitializer() - it requires knowledge of the object being intialized. 3028 3029 InitListExpr *E = new (Context) InitListExpr(LBraceLoc, InitList, NumInit, 3030 RBraceLoc); 3031 E->setType(Context.VoidTy); // FIXME: just a place holder for now. 3032 return Owned(E); 3033} 3034 3035static CastExpr::CastKind getScalarCastKind(ASTContext &Context, 3036 QualType SrcTy, QualType DestTy) { 3037 if (Context.hasSameUnqualifiedType(SrcTy, DestTy)) 3038 return CastExpr::CK_NoOp; 3039 3040 if (SrcTy->hasPointerRepresentation()) { 3041 if (DestTy->hasPointerRepresentation()) 3042 return CastExpr::CK_BitCast; 3043 if (DestTy->isIntegerType()) 3044 return CastExpr::CK_PointerToIntegral; 3045 } 3046 3047 if (SrcTy->isIntegerType()) { 3048 if (DestTy->isIntegerType()) 3049 return CastExpr::CK_IntegralCast; 3050 if (DestTy->hasPointerRepresentation()) 3051 return CastExpr::CK_IntegralToPointer; 3052 if (DestTy->isRealFloatingType()) 3053 return CastExpr::CK_IntegralToFloating; 3054 } 3055 3056 if (SrcTy->isRealFloatingType()) { 3057 if (DestTy->isRealFloatingType()) 3058 return CastExpr::CK_FloatingCast; 3059 if (DestTy->isIntegerType()) 3060 return CastExpr::CK_FloatingToIntegral; 3061 } 3062 3063 // FIXME: Assert here. 3064 // assert(false && "Unhandled cast combination!"); 3065 return CastExpr::CK_Unknown; 3066} 3067 3068/// CheckCastTypes - Check type constraints for casting between types. 3069bool Sema::CheckCastTypes(SourceRange TyR, QualType castType, Expr *&castExpr, 3070 CastExpr::CastKind& Kind, 3071 CXXMethodDecl *& ConversionDecl, 3072 bool FunctionalStyle) { 3073 if (getLangOptions().CPlusPlus) 3074 return CXXCheckCStyleCast(TyR, castType, castExpr, Kind, FunctionalStyle, 3075 ConversionDecl); 3076 3077 DefaultFunctionArrayConversion(castExpr); 3078 3079 // C99 6.5.4p2: the cast type needs to be void or scalar and the expression 3080 // type needs to be scalar. 3081 if (castType->isVoidType()) { 3082 // Cast to void allows any expr type. 3083 Kind = CastExpr::CK_ToVoid; 3084 return false; 3085 } 3086 3087 if (!castType->isScalarType() && !castType->isVectorType()) { 3088 if (Context.hasSameUnqualifiedType(castType, castExpr->getType()) && 3089 (castType->isStructureType() || castType->isUnionType())) { 3090 // GCC struct/union extension: allow cast to self. 3091 // FIXME: Check that the cast destination type is complete. 3092 Diag(TyR.getBegin(), diag::ext_typecheck_cast_nonscalar) 3093 << castType << castExpr->getSourceRange(); 3094 Kind = CastExpr::CK_NoOp; 3095 return false; 3096 } 3097 3098 if (castType->isUnionType()) { 3099 // GCC cast to union extension 3100 RecordDecl *RD = castType->getAs<RecordType>()->getDecl(); 3101 RecordDecl::field_iterator Field, FieldEnd; 3102 for (Field = RD->field_begin(), FieldEnd = RD->field_end(); 3103 Field != FieldEnd; ++Field) { 3104 if (Context.hasSameUnqualifiedType(Field->getType(), 3105 castExpr->getType())) { 3106 Diag(TyR.getBegin(), diag::ext_typecheck_cast_to_union) 3107 << castExpr->getSourceRange(); 3108 break; 3109 } 3110 } 3111 if (Field == FieldEnd) 3112 return Diag(TyR.getBegin(), diag::err_typecheck_cast_to_union_no_type) 3113 << castExpr->getType() << castExpr->getSourceRange(); 3114 Kind = CastExpr::CK_ToUnion; 3115 return false; 3116 } 3117 3118 // Reject any other conversions to non-scalar types. 3119 return Diag(TyR.getBegin(), diag::err_typecheck_cond_expect_scalar) 3120 << castType << castExpr->getSourceRange(); 3121 } 3122 3123 if (!castExpr->getType()->isScalarType() && 3124 !castExpr->getType()->isVectorType()) { 3125 return Diag(castExpr->getLocStart(), 3126 diag::err_typecheck_expect_scalar_operand) 3127 << castExpr->getType() << castExpr->getSourceRange(); 3128 } 3129 3130 if (castType->isExtVectorType()) 3131 return CheckExtVectorCast(TyR, castType, castExpr, Kind); 3132 3133 if (castType->isVectorType()) 3134 return CheckVectorCast(TyR, castType, castExpr->getType(), Kind); 3135 if (castExpr->getType()->isVectorType()) 3136 return CheckVectorCast(TyR, castExpr->getType(), castType, Kind); 3137 3138 if (getLangOptions().ObjC1 && isa<ObjCSuperExpr>(castExpr)) 3139 return Diag(castExpr->getLocStart(), diag::err_illegal_super_cast) << TyR; 3140 3141 if (isa<ObjCSelectorExpr>(castExpr)) 3142 return Diag(castExpr->getLocStart(), diag::err_cast_selector_expr); 3143 3144 if (!castType->isArithmeticType()) { 3145 QualType castExprType = castExpr->getType(); 3146 if (!castExprType->isIntegralType() && castExprType->isArithmeticType()) 3147 return Diag(castExpr->getLocStart(), 3148 diag::err_cast_pointer_from_non_pointer_int) 3149 << castExprType << castExpr->getSourceRange(); 3150 } else if (!castExpr->getType()->isArithmeticType()) { 3151 if (!castType->isIntegralType() && castType->isArithmeticType()) 3152 return Diag(castExpr->getLocStart(), 3153 diag::err_cast_pointer_to_non_pointer_int) 3154 << castType << castExpr->getSourceRange(); 3155 } 3156 3157 Kind = getScalarCastKind(Context, castExpr->getType(), castType); 3158 return false; 3159} 3160 3161bool Sema::CheckVectorCast(SourceRange R, QualType VectorTy, QualType Ty, 3162 CastExpr::CastKind &Kind) { 3163 assert(VectorTy->isVectorType() && "Not a vector type!"); 3164 3165 if (Ty->isVectorType() || Ty->isIntegerType()) { 3166 if (Context.getTypeSize(VectorTy) != Context.getTypeSize(Ty)) 3167 return Diag(R.getBegin(), 3168 Ty->isVectorType() ? 3169 diag::err_invalid_conversion_between_vectors : 3170 diag::err_invalid_conversion_between_vector_and_integer) 3171 << VectorTy << Ty << R; 3172 } else 3173 return Diag(R.getBegin(), 3174 diag::err_invalid_conversion_between_vector_and_scalar) 3175 << VectorTy << Ty << R; 3176 3177 Kind = CastExpr::CK_BitCast; 3178 return false; 3179} 3180 3181bool Sema::CheckExtVectorCast(SourceRange R, QualType DestTy, Expr *&CastExpr, 3182 CastExpr::CastKind &Kind) { 3183 assert(DestTy->isExtVectorType() && "Not an extended vector type!"); 3184 3185 QualType SrcTy = CastExpr->getType(); 3186 3187 // If SrcTy is a VectorType, the total size must match to explicitly cast to 3188 // an ExtVectorType. 3189 if (SrcTy->isVectorType()) { 3190 if (Context.getTypeSize(DestTy) != Context.getTypeSize(SrcTy)) 3191 return Diag(R.getBegin(),diag::err_invalid_conversion_between_ext_vectors) 3192 << DestTy << SrcTy << R; 3193 Kind = CastExpr::CK_BitCast; 3194 return false; 3195 } 3196 3197 // All non-pointer scalars can be cast to ExtVector type. The appropriate 3198 // conversion will take place first from scalar to elt type, and then 3199 // splat from elt type to vector. 3200 if (SrcTy->isPointerType()) 3201 return Diag(R.getBegin(), 3202 diag::err_invalid_conversion_between_vector_and_scalar) 3203 << DestTy << SrcTy << R; 3204 3205 QualType DestElemTy = DestTy->getAs<ExtVectorType>()->getElementType(); 3206 ImpCastExprToType(CastExpr, DestElemTy, 3207 getScalarCastKind(Context, SrcTy, DestElemTy)); 3208 3209 Kind = CastExpr::CK_VectorSplat; 3210 return false; 3211} 3212 3213Action::OwningExprResult 3214Sema::ActOnCastExpr(Scope *S, SourceLocation LParenLoc, TypeTy *Ty, 3215 SourceLocation RParenLoc, ExprArg Op) { 3216 CastExpr::CastKind Kind = CastExpr::CK_Unknown; 3217 3218 assert((Ty != 0) && (Op.get() != 0) && 3219 "ActOnCastExpr(): missing type or expr"); 3220 3221 Expr *castExpr = (Expr *)Op.get(); 3222 //FIXME: Preserve type source info. 3223 QualType castType = GetTypeFromParser(Ty); 3224 3225 // If the Expr being casted is a ParenListExpr, handle it specially. 3226 if (isa<ParenListExpr>(castExpr)) 3227 return ActOnCastOfParenListExpr(S, LParenLoc, RParenLoc, move(Op),castType); 3228 CXXMethodDecl *Method = 0; 3229 if (CheckCastTypes(SourceRange(LParenLoc, RParenLoc), castType, castExpr, 3230 Kind, Method)) 3231 return ExprError(); 3232 3233 if (Method) { 3234 OwningExprResult CastArg = BuildCXXCastArgument(LParenLoc, castType, Kind, 3235 Method, move(Op)); 3236 3237 if (CastArg.isInvalid()) 3238 return ExprError(); 3239 3240 castExpr = CastArg.takeAs<Expr>(); 3241 } else { 3242 Op.release(); 3243 } 3244 3245 return Owned(new (Context) CStyleCastExpr(castType.getNonReferenceType(), 3246 Kind, castExpr, castType, 3247 LParenLoc, RParenLoc)); 3248} 3249 3250/// This is not an AltiVec-style cast, so turn the ParenListExpr into a sequence 3251/// of comma binary operators. 3252Action::OwningExprResult 3253Sema::MaybeConvertParenListExprToParenExpr(Scope *S, ExprArg EA) { 3254 Expr *expr = EA.takeAs<Expr>(); 3255 ParenListExpr *E = dyn_cast<ParenListExpr>(expr); 3256 if (!E) 3257 return Owned(expr); 3258 3259 OwningExprResult Result(*this, E->getExpr(0)); 3260 3261 for (unsigned i = 1, e = E->getNumExprs(); i != e && !Result.isInvalid(); ++i) 3262 Result = ActOnBinOp(S, E->getExprLoc(), tok::comma, move(Result), 3263 Owned(E->getExpr(i))); 3264 3265 return ActOnParenExpr(E->getLParenLoc(), E->getRParenLoc(), move(Result)); 3266} 3267 3268Action::OwningExprResult 3269Sema::ActOnCastOfParenListExpr(Scope *S, SourceLocation LParenLoc, 3270 SourceLocation RParenLoc, ExprArg Op, 3271 QualType Ty) { 3272 ParenListExpr *PE = (ParenListExpr *)Op.get(); 3273 3274 // If this is an altivec initializer, '(' type ')' '(' init, ..., init ')' 3275 // then handle it as such. 3276 if (getLangOptions().AltiVec && Ty->isVectorType()) { 3277 if (PE->getNumExprs() == 0) { 3278 Diag(PE->getExprLoc(), diag::err_altivec_empty_initializer); 3279 return ExprError(); 3280 } 3281 3282 llvm::SmallVector<Expr *, 8> initExprs; 3283 for (unsigned i = 0, e = PE->getNumExprs(); i != e; ++i) 3284 initExprs.push_back(PE->getExpr(i)); 3285 3286 // FIXME: This means that pretty-printing the final AST will produce curly 3287 // braces instead of the original commas. 3288 Op.release(); 3289 InitListExpr *E = new (Context) InitListExpr(LParenLoc, &initExprs[0], 3290 initExprs.size(), RParenLoc); 3291 E->setType(Ty); 3292 return ActOnCompoundLiteral(LParenLoc, Ty.getAsOpaquePtr(), RParenLoc, 3293 Owned(E)); 3294 } else { 3295 // This is not an AltiVec-style cast, so turn the ParenListExpr into a 3296 // sequence of BinOp comma operators. 3297 Op = MaybeConvertParenListExprToParenExpr(S, move(Op)); 3298 return ActOnCastExpr(S, LParenLoc, Ty.getAsOpaquePtr(), RParenLoc,move(Op)); 3299 } 3300} 3301 3302Action::OwningExprResult Sema::ActOnParenListExpr(SourceLocation L, 3303 SourceLocation R, 3304 MultiExprArg Val) { 3305 unsigned nexprs = Val.size(); 3306 Expr **exprs = reinterpret_cast<Expr**>(Val.release()); 3307 assert((exprs != 0) && "ActOnParenListExpr() missing expr list"); 3308 Expr *expr = new (Context) ParenListExpr(Context, L, exprs, nexprs, R); 3309 return Owned(expr); 3310} 3311 3312/// Note that lhs is not null here, even if this is the gnu "x ?: y" extension. 3313/// In that case, lhs = cond. 3314/// C99 6.5.15 3315QualType Sema::CheckConditionalOperands(Expr *&Cond, Expr *&LHS, Expr *&RHS, 3316 SourceLocation QuestionLoc) { 3317 // C++ is sufficiently different to merit its own checker. 3318 if (getLangOptions().CPlusPlus) 3319 return CXXCheckConditionalOperands(Cond, LHS, RHS, QuestionLoc); 3320 3321 CheckSignCompare(LHS, RHS, QuestionLoc, diag::warn_mixed_sign_conditional); 3322 3323 UsualUnaryConversions(Cond); 3324 UsualUnaryConversions(LHS); 3325 UsualUnaryConversions(RHS); 3326 QualType CondTy = Cond->getType(); 3327 QualType LHSTy = LHS->getType(); 3328 QualType RHSTy = RHS->getType(); 3329 3330 // first, check the condition. 3331 if (!CondTy->isScalarType()) { // C99 6.5.15p2 3332 Diag(Cond->getLocStart(), diag::err_typecheck_cond_expect_scalar) 3333 << CondTy; 3334 return QualType(); 3335 } 3336 3337 // Now check the two expressions. 3338 if (LHSTy->isVectorType() || RHSTy->isVectorType()) 3339 return CheckVectorOperands(QuestionLoc, LHS, RHS); 3340 3341 // If both operands have arithmetic type, do the usual arithmetic conversions 3342 // to find a common type: C99 6.5.15p3,5. 3343 if (LHSTy->isArithmeticType() && RHSTy->isArithmeticType()) { 3344 UsualArithmeticConversions(LHS, RHS); 3345 return LHS->getType(); 3346 } 3347 3348 // If both operands are the same structure or union type, the result is that 3349 // type. 3350 if (const RecordType *LHSRT = LHSTy->getAs<RecordType>()) { // C99 6.5.15p3 3351 if (const RecordType *RHSRT = RHSTy->getAs<RecordType>()) 3352 if (LHSRT->getDecl() == RHSRT->getDecl()) 3353 // "If both the operands have structure or union type, the result has 3354 // that type." This implies that CV qualifiers are dropped. 3355 return LHSTy.getUnqualifiedType(); 3356 // FIXME: Type of conditional expression must be complete in C mode. 3357 } 3358 3359 // C99 6.5.15p5: "If both operands have void type, the result has void type." 3360 // The following || allows only one side to be void (a GCC-ism). 3361 if (LHSTy->isVoidType() || RHSTy->isVoidType()) { 3362 if (!LHSTy->isVoidType()) 3363 Diag(RHS->getLocStart(), diag::ext_typecheck_cond_one_void) 3364 << RHS->getSourceRange(); 3365 if (!RHSTy->isVoidType()) 3366 Diag(LHS->getLocStart(), diag::ext_typecheck_cond_one_void) 3367 << LHS->getSourceRange(); 3368 ImpCastExprToType(LHS, Context.VoidTy, CastExpr::CK_ToVoid); 3369 ImpCastExprToType(RHS, Context.VoidTy, CastExpr::CK_ToVoid); 3370 return Context.VoidTy; 3371 } 3372 // C99 6.5.15p6 - "if one operand is a null pointer constant, the result has 3373 // the type of the other operand." 3374 if ((LHSTy->isAnyPointerType() || LHSTy->isBlockPointerType()) && 3375 RHS->isNullPointerConstant(Context, Expr::NPC_ValueDependentIsNull)) { 3376 // promote the null to a pointer. 3377 ImpCastExprToType(RHS, LHSTy, CastExpr::CK_Unknown); 3378 return LHSTy; 3379 } 3380 if ((RHSTy->isAnyPointerType() || RHSTy->isBlockPointerType()) && 3381 LHS->isNullPointerConstant(Context, Expr::NPC_ValueDependentIsNull)) { 3382 ImpCastExprToType(LHS, RHSTy, CastExpr::CK_Unknown); 3383 return RHSTy; 3384 } 3385 // Handle things like Class and struct objc_class*. Here we case the result 3386 // to the pseudo-builtin, because that will be implicitly cast back to the 3387 // redefinition type if an attempt is made to access its fields. 3388 if (LHSTy->isObjCClassType() && 3389 (RHSTy.getDesugaredType() == Context.ObjCClassRedefinitionType)) { 3390 ImpCastExprToType(RHS, LHSTy, CastExpr::CK_BitCast); 3391 return LHSTy; 3392 } 3393 if (RHSTy->isObjCClassType() && 3394 (LHSTy.getDesugaredType() == Context.ObjCClassRedefinitionType)) { 3395 ImpCastExprToType(LHS, RHSTy, CastExpr::CK_BitCast); 3396 return RHSTy; 3397 } 3398 // And the same for struct objc_object* / id 3399 if (LHSTy->isObjCIdType() && 3400 (RHSTy.getDesugaredType() == Context.ObjCIdRedefinitionType)) { 3401 ImpCastExprToType(RHS, LHSTy, CastExpr::CK_BitCast); 3402 return LHSTy; 3403 } 3404 if (RHSTy->isObjCIdType() && 3405 (LHSTy.getDesugaredType() == Context.ObjCIdRedefinitionType)) { 3406 ImpCastExprToType(LHS, RHSTy, CastExpr::CK_BitCast); 3407 return RHSTy; 3408 } 3409 // Handle block pointer types. 3410 if (LHSTy->isBlockPointerType() || RHSTy->isBlockPointerType()) { 3411 if (!LHSTy->isBlockPointerType() || !RHSTy->isBlockPointerType()) { 3412 if (LHSTy->isVoidPointerType() || RHSTy->isVoidPointerType()) { 3413 QualType destType = Context.getPointerType(Context.VoidTy); 3414 ImpCastExprToType(LHS, destType, CastExpr::CK_BitCast); 3415 ImpCastExprToType(RHS, destType, CastExpr::CK_BitCast); 3416 return destType; 3417 } 3418 Diag(QuestionLoc, diag::err_typecheck_cond_incompatible_operands) 3419 << LHSTy << RHSTy << LHS->getSourceRange() << RHS->getSourceRange(); 3420 return QualType(); 3421 } 3422 // We have 2 block pointer types. 3423 if (Context.getCanonicalType(LHSTy) == Context.getCanonicalType(RHSTy)) { 3424 // Two identical block pointer types are always compatible. 3425 return LHSTy; 3426 } 3427 // The block pointer types aren't identical, continue checking. 3428 QualType lhptee = LHSTy->getAs<BlockPointerType>()->getPointeeType(); 3429 QualType rhptee = RHSTy->getAs<BlockPointerType>()->getPointeeType(); 3430 3431 if (!Context.typesAreCompatible(lhptee.getUnqualifiedType(), 3432 rhptee.getUnqualifiedType())) { 3433 Diag(QuestionLoc, diag::warn_typecheck_cond_incompatible_pointers) 3434 << LHSTy << RHSTy << LHS->getSourceRange() << RHS->getSourceRange(); 3435 // In this situation, we assume void* type. No especially good 3436 // reason, but this is what gcc does, and we do have to pick 3437 // to get a consistent AST. 3438 QualType incompatTy = Context.getPointerType(Context.VoidTy); 3439 ImpCastExprToType(LHS, incompatTy, CastExpr::CK_BitCast); 3440 ImpCastExprToType(RHS, incompatTy, CastExpr::CK_BitCast); 3441 return incompatTy; 3442 } 3443 // The block pointer types are compatible. 3444 ImpCastExprToType(LHS, LHSTy, CastExpr::CK_BitCast); 3445 ImpCastExprToType(RHS, LHSTy, CastExpr::CK_BitCast); 3446 return LHSTy; 3447 } 3448 // Check constraints for Objective-C object pointers types. 3449 if (LHSTy->isObjCObjectPointerType() && RHSTy->isObjCObjectPointerType()) { 3450 3451 if (Context.getCanonicalType(LHSTy) == Context.getCanonicalType(RHSTy)) { 3452 // Two identical object pointer types are always compatible. 3453 return LHSTy; 3454 } 3455 const ObjCObjectPointerType *LHSOPT = LHSTy->getAs<ObjCObjectPointerType>(); 3456 const ObjCObjectPointerType *RHSOPT = RHSTy->getAs<ObjCObjectPointerType>(); 3457 QualType compositeType = LHSTy; 3458 3459 // If both operands are interfaces and either operand can be 3460 // assigned to the other, use that type as the composite 3461 // type. This allows 3462 // xxx ? (A*) a : (B*) b 3463 // where B is a subclass of A. 3464 // 3465 // Additionally, as for assignment, if either type is 'id' 3466 // allow silent coercion. Finally, if the types are 3467 // incompatible then make sure to use 'id' as the composite 3468 // type so the result is acceptable for sending messages to. 3469 3470 // FIXME: Consider unifying with 'areComparableObjCPointerTypes'. 3471 // It could return the composite type. 3472 if (Context.canAssignObjCInterfaces(LHSOPT, RHSOPT)) { 3473 compositeType = RHSOPT->isObjCBuiltinType() ? RHSTy : LHSTy; 3474 } else if (Context.canAssignObjCInterfaces(RHSOPT, LHSOPT)) { 3475 compositeType = LHSOPT->isObjCBuiltinType() ? LHSTy : RHSTy; 3476 } else if ((LHSTy->isObjCQualifiedIdType() || 3477 RHSTy->isObjCQualifiedIdType()) && 3478 Context.ObjCQualifiedIdTypesAreCompatible(LHSTy, RHSTy, true)) { 3479 // Need to handle "id<xx>" explicitly. 3480 // GCC allows qualified id and any Objective-C type to devolve to 3481 // id. Currently localizing to here until clear this should be 3482 // part of ObjCQualifiedIdTypesAreCompatible. 3483 compositeType = Context.getObjCIdType(); 3484 } else if (LHSTy->isObjCIdType() || RHSTy->isObjCIdType()) { 3485 compositeType = Context.getObjCIdType(); 3486 } else if (!(compositeType = 3487 Context.areCommonBaseCompatible(LHSOPT, RHSOPT)).isNull()) 3488 ; 3489 else { 3490 Diag(QuestionLoc, diag::ext_typecheck_cond_incompatible_operands) 3491 << LHSTy << RHSTy 3492 << LHS->getSourceRange() << RHS->getSourceRange(); 3493 QualType incompatTy = Context.getObjCIdType(); 3494 ImpCastExprToType(LHS, incompatTy, CastExpr::CK_BitCast); 3495 ImpCastExprToType(RHS, incompatTy, CastExpr::CK_BitCast); 3496 return incompatTy; 3497 } 3498 // The object pointer types are compatible. 3499 ImpCastExprToType(LHS, compositeType, CastExpr::CK_BitCast); 3500 ImpCastExprToType(RHS, compositeType, CastExpr::CK_BitCast); 3501 return compositeType; 3502 } 3503 // Check Objective-C object pointer types and 'void *' 3504 if (LHSTy->isVoidPointerType() && RHSTy->isObjCObjectPointerType()) { 3505 QualType lhptee = LHSTy->getAs<PointerType>()->getPointeeType(); 3506 QualType rhptee = RHSTy->getAs<ObjCObjectPointerType>()->getPointeeType(); 3507 QualType destPointee 3508 = Context.getQualifiedType(lhptee, rhptee.getQualifiers()); 3509 QualType destType = Context.getPointerType(destPointee); 3510 // Add qualifiers if necessary. 3511 ImpCastExprToType(LHS, destType, CastExpr::CK_NoOp); 3512 // Promote to void*. 3513 ImpCastExprToType(RHS, destType, CastExpr::CK_BitCast); 3514 return destType; 3515 } 3516 if (LHSTy->isObjCObjectPointerType() && RHSTy->isVoidPointerType()) { 3517 QualType lhptee = LHSTy->getAs<ObjCObjectPointerType>()->getPointeeType(); 3518 QualType rhptee = RHSTy->getAs<PointerType>()->getPointeeType(); 3519 QualType destPointee 3520 = Context.getQualifiedType(rhptee, lhptee.getQualifiers()); 3521 QualType destType = Context.getPointerType(destPointee); 3522 // Add qualifiers if necessary. 3523 ImpCastExprToType(RHS, destType, CastExpr::CK_NoOp); 3524 // Promote to void*. 3525 ImpCastExprToType(LHS, destType, CastExpr::CK_BitCast); 3526 return destType; 3527 } 3528 // Check constraints for C object pointers types (C99 6.5.15p3,6). 3529 if (LHSTy->isPointerType() && RHSTy->isPointerType()) { 3530 // get the "pointed to" types 3531 QualType lhptee = LHSTy->getAs<PointerType>()->getPointeeType(); 3532 QualType rhptee = RHSTy->getAs<PointerType>()->getPointeeType(); 3533 3534 // ignore qualifiers on void (C99 6.5.15p3, clause 6) 3535 if (lhptee->isVoidType() && rhptee->isIncompleteOrObjectType()) { 3536 // Figure out necessary qualifiers (C99 6.5.15p6) 3537 QualType destPointee 3538 = Context.getQualifiedType(lhptee, rhptee.getQualifiers()); 3539 QualType destType = Context.getPointerType(destPointee); 3540 // Add qualifiers if necessary. 3541 ImpCastExprToType(LHS, destType, CastExpr::CK_NoOp); 3542 // Promote to void*. 3543 ImpCastExprToType(RHS, destType, CastExpr::CK_BitCast); 3544 return destType; 3545 } 3546 if (rhptee->isVoidType() && lhptee->isIncompleteOrObjectType()) { 3547 QualType destPointee 3548 = Context.getQualifiedType(rhptee, lhptee.getQualifiers()); 3549 QualType destType = Context.getPointerType(destPointee); 3550 // Add qualifiers if necessary. 3551 ImpCastExprToType(RHS, destType, CastExpr::CK_NoOp); 3552 // Promote to void*. 3553 ImpCastExprToType(LHS, destType, CastExpr::CK_BitCast); 3554 return destType; 3555 } 3556 3557 if (Context.getCanonicalType(LHSTy) == Context.getCanonicalType(RHSTy)) { 3558 // Two identical pointer types are always compatible. 3559 return LHSTy; 3560 } 3561 if (!Context.typesAreCompatible(lhptee.getUnqualifiedType(), 3562 rhptee.getUnqualifiedType())) { 3563 Diag(QuestionLoc, diag::warn_typecheck_cond_incompatible_pointers) 3564 << LHSTy << RHSTy << LHS->getSourceRange() << RHS->getSourceRange(); 3565 // In this situation, we assume void* type. No especially good 3566 // reason, but this is what gcc does, and we do have to pick 3567 // to get a consistent AST. 3568 QualType incompatTy = Context.getPointerType(Context.VoidTy); 3569 ImpCastExprToType(LHS, incompatTy, CastExpr::CK_BitCast); 3570 ImpCastExprToType(RHS, incompatTy, CastExpr::CK_BitCast); 3571 return incompatTy; 3572 } 3573 // The pointer types are compatible. 3574 // C99 6.5.15p6: If both operands are pointers to compatible types *or* to 3575 // differently qualified versions of compatible types, the result type is 3576 // a pointer to an appropriately qualified version of the *composite* 3577 // type. 3578 // FIXME: Need to calculate the composite type. 3579 // FIXME: Need to add qualifiers 3580 ImpCastExprToType(LHS, LHSTy, CastExpr::CK_BitCast); 3581 ImpCastExprToType(RHS, LHSTy, CastExpr::CK_BitCast); 3582 return LHSTy; 3583 } 3584 3585 // GCC compatibility: soften pointer/integer mismatch. 3586 if (RHSTy->isPointerType() && LHSTy->isIntegerType()) { 3587 Diag(QuestionLoc, diag::warn_typecheck_cond_pointer_integer_mismatch) 3588 << LHSTy << RHSTy << LHS->getSourceRange() << RHS->getSourceRange(); 3589 ImpCastExprToType(LHS, RHSTy, CastExpr::CK_IntegralToPointer); 3590 return RHSTy; 3591 } 3592 if (LHSTy->isPointerType() && RHSTy->isIntegerType()) { 3593 Diag(QuestionLoc, diag::warn_typecheck_cond_pointer_integer_mismatch) 3594 << LHSTy << RHSTy << LHS->getSourceRange() << RHS->getSourceRange(); 3595 ImpCastExprToType(RHS, LHSTy, CastExpr::CK_IntegralToPointer); 3596 return LHSTy; 3597 } 3598 3599 // Otherwise, the operands are not compatible. 3600 Diag(QuestionLoc, diag::err_typecheck_cond_incompatible_operands) 3601 << LHSTy << RHSTy << LHS->getSourceRange() << RHS->getSourceRange(); 3602 return QualType(); 3603} 3604 3605/// ActOnConditionalOp - Parse a ?: operation. Note that 'LHS' may be null 3606/// in the case of a the GNU conditional expr extension. 3607Action::OwningExprResult Sema::ActOnConditionalOp(SourceLocation QuestionLoc, 3608 SourceLocation ColonLoc, 3609 ExprArg Cond, ExprArg LHS, 3610 ExprArg RHS) { 3611 Expr *CondExpr = (Expr *) Cond.get(); 3612 Expr *LHSExpr = (Expr *) LHS.get(), *RHSExpr = (Expr *) RHS.get(); 3613 3614 // If this is the gnu "x ?: y" extension, analyze the types as though the LHS 3615 // was the condition. 3616 bool isLHSNull = LHSExpr == 0; 3617 if (isLHSNull) 3618 LHSExpr = CondExpr; 3619 3620 QualType result = CheckConditionalOperands(CondExpr, LHSExpr, 3621 RHSExpr, QuestionLoc); 3622 if (result.isNull()) 3623 return ExprError(); 3624 3625 Cond.release(); 3626 LHS.release(); 3627 RHS.release(); 3628 return Owned(new (Context) ConditionalOperator(CondExpr, QuestionLoc, 3629 isLHSNull ? 0 : LHSExpr, 3630 ColonLoc, RHSExpr, result)); 3631} 3632 3633// CheckPointerTypesForAssignment - This is a very tricky routine (despite 3634// being closely modeled after the C99 spec:-). The odd characteristic of this 3635// routine is it effectively iqnores the qualifiers on the top level pointee. 3636// This circumvents the usual type rules specified in 6.2.7p1 & 6.7.5.[1-3]. 3637// FIXME: add a couple examples in this comment. 3638Sema::AssignConvertType 3639Sema::CheckPointerTypesForAssignment(QualType lhsType, QualType rhsType) { 3640 QualType lhptee, rhptee; 3641 3642 if ((lhsType->isObjCClassType() && 3643 (rhsType.getDesugaredType() == Context.ObjCClassRedefinitionType)) || 3644 (rhsType->isObjCClassType() && 3645 (lhsType.getDesugaredType() == Context.ObjCClassRedefinitionType))) { 3646 return Compatible; 3647 } 3648 3649 // get the "pointed to" type (ignoring qualifiers at the top level) 3650 lhptee = lhsType->getAs<PointerType>()->getPointeeType(); 3651 rhptee = rhsType->getAs<PointerType>()->getPointeeType(); 3652 3653 // make sure we operate on the canonical type 3654 lhptee = Context.getCanonicalType(lhptee); 3655 rhptee = Context.getCanonicalType(rhptee); 3656 3657 AssignConvertType ConvTy = Compatible; 3658 3659 // C99 6.5.16.1p1: This following citation is common to constraints 3660 // 3 & 4 (below). ...and the type *pointed to* by the left has all the 3661 // qualifiers of the type *pointed to* by the right; 3662 // FIXME: Handle ExtQualType 3663 if (!lhptee.isAtLeastAsQualifiedAs(rhptee)) 3664 ConvTy = CompatiblePointerDiscardsQualifiers; 3665 3666 // C99 6.5.16.1p1 (constraint 4): If one operand is a pointer to an object or 3667 // incomplete type and the other is a pointer to a qualified or unqualified 3668 // version of void... 3669 if (lhptee->isVoidType()) { 3670 if (rhptee->isIncompleteOrObjectType()) 3671 return ConvTy; 3672 3673 // As an extension, we allow cast to/from void* to function pointer. 3674 assert(rhptee->isFunctionType()); 3675 return FunctionVoidPointer; 3676 } 3677 3678 if (rhptee->isVoidType()) { 3679 if (lhptee->isIncompleteOrObjectType()) 3680 return ConvTy; 3681 3682 // As an extension, we allow cast to/from void* to function pointer. 3683 assert(lhptee->isFunctionType()); 3684 return FunctionVoidPointer; 3685 } 3686 // C99 6.5.16.1p1 (constraint 3): both operands are pointers to qualified or 3687 // unqualified versions of compatible types, ... 3688 lhptee = lhptee.getUnqualifiedType(); 3689 rhptee = rhptee.getUnqualifiedType(); 3690 if (!Context.typesAreCompatible(lhptee, rhptee)) { 3691 // Check if the pointee types are compatible ignoring the sign. 3692 // We explicitly check for char so that we catch "char" vs 3693 // "unsigned char" on systems where "char" is unsigned. 3694 if (lhptee->isCharType()) 3695 lhptee = Context.UnsignedCharTy; 3696 else if (lhptee->isSignedIntegerType()) 3697 lhptee = Context.getCorrespondingUnsignedType(lhptee); 3698 3699 if (rhptee->isCharType()) 3700 rhptee = Context.UnsignedCharTy; 3701 else if (rhptee->isSignedIntegerType()) 3702 rhptee = Context.getCorrespondingUnsignedType(rhptee); 3703 3704 if (lhptee == rhptee) { 3705 // Types are compatible ignoring the sign. Qualifier incompatibility 3706 // takes priority over sign incompatibility because the sign 3707 // warning can be disabled. 3708 if (ConvTy != Compatible) 3709 return ConvTy; 3710 return IncompatiblePointerSign; 3711 } 3712 3713 // If we are a multi-level pointer, it's possible that our issue is simply 3714 // one of qualification - e.g. char ** -> const char ** is not allowed. If 3715 // the eventual target type is the same and the pointers have the same 3716 // level of indirection, this must be the issue. 3717 if (lhptee->isPointerType() && rhptee->isPointerType()) { 3718 do { 3719 lhptee = lhptee->getAs<PointerType>()->getPointeeType(); 3720 rhptee = rhptee->getAs<PointerType>()->getPointeeType(); 3721 3722 lhptee = Context.getCanonicalType(lhptee); 3723 rhptee = Context.getCanonicalType(rhptee); 3724 } while (lhptee->isPointerType() && rhptee->isPointerType()); 3725 3726 if (Context.hasSameUnqualifiedType(lhptee, rhptee)) 3727 return IncompatibleNestedPointerQualifiers; 3728 } 3729 3730 // General pointer incompatibility takes priority over qualifiers. 3731 return IncompatiblePointer; 3732 } 3733 return ConvTy; 3734} 3735 3736/// CheckBlockPointerTypesForAssignment - This routine determines whether two 3737/// block pointer types are compatible or whether a block and normal pointer 3738/// are compatible. It is more restrict than comparing two function pointer 3739// types. 3740Sema::AssignConvertType 3741Sema::CheckBlockPointerTypesForAssignment(QualType lhsType, 3742 QualType rhsType) { 3743 QualType lhptee, rhptee; 3744 3745 // get the "pointed to" type (ignoring qualifiers at the top level) 3746 lhptee = lhsType->getAs<BlockPointerType>()->getPointeeType(); 3747 rhptee = rhsType->getAs<BlockPointerType>()->getPointeeType(); 3748 3749 // make sure we operate on the canonical type 3750 lhptee = Context.getCanonicalType(lhptee); 3751 rhptee = Context.getCanonicalType(rhptee); 3752 3753 AssignConvertType ConvTy = Compatible; 3754 3755 // For blocks we enforce that qualifiers are identical. 3756 if (lhptee.getLocalCVRQualifiers() != rhptee.getLocalCVRQualifiers()) 3757 ConvTy = CompatiblePointerDiscardsQualifiers; 3758 3759 if (!Context.typesAreCompatible(lhptee, rhptee)) 3760 return IncompatibleBlockPointer; 3761 return ConvTy; 3762} 3763 3764/// CheckAssignmentConstraints (C99 6.5.16) - This routine currently 3765/// has code to accommodate several GCC extensions when type checking 3766/// pointers. Here are some objectionable examples that GCC considers warnings: 3767/// 3768/// int a, *pint; 3769/// short *pshort; 3770/// struct foo *pfoo; 3771/// 3772/// pint = pshort; // warning: assignment from incompatible pointer type 3773/// a = pint; // warning: assignment makes integer from pointer without a cast 3774/// pint = a; // warning: assignment makes pointer from integer without a cast 3775/// pint = pfoo; // warning: assignment from incompatible pointer type 3776/// 3777/// As a result, the code for dealing with pointers is more complex than the 3778/// C99 spec dictates. 3779/// 3780Sema::AssignConvertType 3781Sema::CheckAssignmentConstraints(QualType lhsType, QualType rhsType) { 3782 // Get canonical types. We're not formatting these types, just comparing 3783 // them. 3784 lhsType = Context.getCanonicalType(lhsType).getUnqualifiedType(); 3785 rhsType = Context.getCanonicalType(rhsType).getUnqualifiedType(); 3786 3787 if (lhsType == rhsType) 3788 return Compatible; // Common case: fast path an exact match. 3789 3790 if ((lhsType->isObjCClassType() && 3791 (rhsType.getDesugaredType() == Context.ObjCClassRedefinitionType)) || 3792 (rhsType->isObjCClassType() && 3793 (lhsType.getDesugaredType() == Context.ObjCClassRedefinitionType))) { 3794 return Compatible; 3795 } 3796 3797 // If the left-hand side is a reference type, then we are in a 3798 // (rare!) case where we've allowed the use of references in C, 3799 // e.g., as a parameter type in a built-in function. In this case, 3800 // just make sure that the type referenced is compatible with the 3801 // right-hand side type. The caller is responsible for adjusting 3802 // lhsType so that the resulting expression does not have reference 3803 // type. 3804 if (const ReferenceType *lhsTypeRef = lhsType->getAs<ReferenceType>()) { 3805 if (Context.typesAreCompatible(lhsTypeRef->getPointeeType(), rhsType)) 3806 return Compatible; 3807 return Incompatible; 3808 } 3809 // Allow scalar to ExtVector assignments, and assignments of an ExtVector type 3810 // to the same ExtVector type. 3811 if (lhsType->isExtVectorType()) { 3812 if (rhsType->isExtVectorType()) 3813 return lhsType == rhsType ? Compatible : Incompatible; 3814 if (!rhsType->isVectorType() && rhsType->isArithmeticType()) 3815 return Compatible; 3816 } 3817 3818 if (lhsType->isVectorType() || rhsType->isVectorType()) { 3819 // If we are allowing lax vector conversions, and LHS and RHS are both 3820 // vectors, the total size only needs to be the same. This is a bitcast; 3821 // no bits are changed but the result type is different. 3822 if (getLangOptions().LaxVectorConversions && 3823 lhsType->isVectorType() && rhsType->isVectorType()) { 3824 if (Context.getTypeSize(lhsType) == Context.getTypeSize(rhsType)) 3825 return IncompatibleVectors; 3826 } 3827 return Incompatible; 3828 } 3829 3830 if (lhsType->isArithmeticType() && rhsType->isArithmeticType()) 3831 return Compatible; 3832 3833 if (isa<PointerType>(lhsType)) { 3834 if (rhsType->isIntegerType()) 3835 return IntToPointer; 3836 3837 if (isa<PointerType>(rhsType)) 3838 return CheckPointerTypesForAssignment(lhsType, rhsType); 3839 3840 // In general, C pointers are not compatible with ObjC object pointers. 3841 if (isa<ObjCObjectPointerType>(rhsType)) { 3842 if (lhsType->isVoidPointerType()) // an exception to the rule. 3843 return Compatible; 3844 return IncompatiblePointer; 3845 } 3846 if (rhsType->getAs<BlockPointerType>()) { 3847 if (lhsType->getAs<PointerType>()->getPointeeType()->isVoidType()) 3848 return Compatible; 3849 3850 // Treat block pointers as objects. 3851 if (getLangOptions().ObjC1 && lhsType->isObjCIdType()) 3852 return Compatible; 3853 } 3854 return Incompatible; 3855 } 3856 3857 if (isa<BlockPointerType>(lhsType)) { 3858 if (rhsType->isIntegerType()) 3859 return IntToBlockPointer; 3860 3861 // Treat block pointers as objects. 3862 if (getLangOptions().ObjC1 && rhsType->isObjCIdType()) 3863 return Compatible; 3864 3865 if (rhsType->isBlockPointerType()) 3866 return CheckBlockPointerTypesForAssignment(lhsType, rhsType); 3867 3868 if (const PointerType *RHSPT = rhsType->getAs<PointerType>()) { 3869 if (RHSPT->getPointeeType()->isVoidType()) 3870 return Compatible; 3871 } 3872 return Incompatible; 3873 } 3874 3875 if (isa<ObjCObjectPointerType>(lhsType)) { 3876 if (rhsType->isIntegerType()) 3877 return IntToPointer; 3878 3879 // In general, C pointers are not compatible with ObjC object pointers. 3880 if (isa<PointerType>(rhsType)) { 3881 if (rhsType->isVoidPointerType()) // an exception to the rule. 3882 return Compatible; 3883 return IncompatiblePointer; 3884 } 3885 if (rhsType->isObjCObjectPointerType()) { 3886 if (lhsType->isObjCBuiltinType() || rhsType->isObjCBuiltinType()) 3887 return Compatible; 3888 if (Context.typesAreCompatible(lhsType, rhsType)) 3889 return Compatible; 3890 if (lhsType->isObjCQualifiedIdType() || rhsType->isObjCQualifiedIdType()) 3891 return IncompatibleObjCQualifiedId; 3892 return IncompatiblePointer; 3893 } 3894 if (const PointerType *RHSPT = rhsType->getAs<PointerType>()) { 3895 if (RHSPT->getPointeeType()->isVoidType()) 3896 return Compatible; 3897 } 3898 // Treat block pointers as objects. 3899 if (rhsType->isBlockPointerType()) 3900 return Compatible; 3901 return Incompatible; 3902 } 3903 if (isa<PointerType>(rhsType)) { 3904 // C99 6.5.16.1p1: the left operand is _Bool and the right is a pointer. 3905 if (lhsType == Context.BoolTy) 3906 return Compatible; 3907 3908 if (lhsType->isIntegerType()) 3909 return PointerToInt; 3910 3911 if (isa<PointerType>(lhsType)) 3912 return CheckPointerTypesForAssignment(lhsType, rhsType); 3913 3914 if (isa<BlockPointerType>(lhsType) && 3915 rhsType->getAs<PointerType>()->getPointeeType()->isVoidType()) 3916 return Compatible; 3917 return Incompatible; 3918 } 3919 if (isa<ObjCObjectPointerType>(rhsType)) { 3920 // C99 6.5.16.1p1: the left operand is _Bool and the right is a pointer. 3921 if (lhsType == Context.BoolTy) 3922 return Compatible; 3923 3924 if (lhsType->isIntegerType()) 3925 return PointerToInt; 3926 3927 // In general, C pointers are not compatible with ObjC object pointers. 3928 if (isa<PointerType>(lhsType)) { 3929 if (lhsType->isVoidPointerType()) // an exception to the rule. 3930 return Compatible; 3931 return IncompatiblePointer; 3932 } 3933 if (isa<BlockPointerType>(lhsType) && 3934 rhsType->getAs<PointerType>()->getPointeeType()->isVoidType()) 3935 return Compatible; 3936 return Incompatible; 3937 } 3938 3939 if (isa<TagType>(lhsType) && isa<TagType>(rhsType)) { 3940 if (Context.typesAreCompatible(lhsType, rhsType)) 3941 return Compatible; 3942 } 3943 return Incompatible; 3944} 3945 3946/// \brief Constructs a transparent union from an expression that is 3947/// used to initialize the transparent union. 3948static void ConstructTransparentUnion(ASTContext &C, Expr *&E, 3949 QualType UnionType, FieldDecl *Field) { 3950 // Build an initializer list that designates the appropriate member 3951 // of the transparent union. 3952 InitListExpr *Initializer = new (C) InitListExpr(SourceLocation(), 3953 &E, 1, 3954 SourceLocation()); 3955 Initializer->setType(UnionType); 3956 Initializer->setInitializedFieldInUnion(Field); 3957 3958 // Build a compound literal constructing a value of the transparent 3959 // union type from this initializer list. 3960 E = new (C) CompoundLiteralExpr(SourceLocation(), UnionType, Initializer, 3961 false); 3962} 3963 3964Sema::AssignConvertType 3965Sema::CheckTransparentUnionArgumentConstraints(QualType ArgType, Expr *&rExpr) { 3966 QualType FromType = rExpr->getType(); 3967 3968 // If the ArgType is a Union type, we want to handle a potential 3969 // transparent_union GCC extension. 3970 const RecordType *UT = ArgType->getAsUnionType(); 3971 if (!UT || !UT->getDecl()->hasAttr<TransparentUnionAttr>()) 3972 return Incompatible; 3973 3974 // The field to initialize within the transparent union. 3975 RecordDecl *UD = UT->getDecl(); 3976 FieldDecl *InitField = 0; 3977 // It's compatible if the expression matches any of the fields. 3978 for (RecordDecl::field_iterator it = UD->field_begin(), 3979 itend = UD->field_end(); 3980 it != itend; ++it) { 3981 if (it->getType()->isPointerType()) { 3982 // If the transparent union contains a pointer type, we allow: 3983 // 1) void pointer 3984 // 2) null pointer constant 3985 if (FromType->isPointerType()) 3986 if (FromType->getAs<PointerType>()->getPointeeType()->isVoidType()) { 3987 ImpCastExprToType(rExpr, it->getType(), CastExpr::CK_BitCast); 3988 InitField = *it; 3989 break; 3990 } 3991 3992 if (rExpr->isNullPointerConstant(Context, 3993 Expr::NPC_ValueDependentIsNull)) { 3994 ImpCastExprToType(rExpr, it->getType(), CastExpr::CK_IntegralToPointer); 3995 InitField = *it; 3996 break; 3997 } 3998 } 3999 4000 if (CheckAssignmentConstraints(it->getType(), rExpr->getType()) 4001 == Compatible) { 4002 InitField = *it; 4003 break; 4004 } 4005 } 4006 4007 if (!InitField) 4008 return Incompatible; 4009 4010 ConstructTransparentUnion(Context, rExpr, ArgType, InitField); 4011 return Compatible; 4012} 4013 4014Sema::AssignConvertType 4015Sema::CheckSingleAssignmentConstraints(QualType lhsType, Expr *&rExpr) { 4016 if (getLangOptions().CPlusPlus) { 4017 if (!lhsType->isRecordType()) { 4018 // C++ 5.17p3: If the left operand is not of class type, the 4019 // expression is implicitly converted (C++ 4) to the 4020 // cv-unqualified type of the left operand. 4021 if (PerformImplicitConversion(rExpr, lhsType.getUnqualifiedType(), 4022 "assigning")) 4023 return Incompatible; 4024 return Compatible; 4025 } 4026 4027 // FIXME: Currently, we fall through and treat C++ classes like C 4028 // structures. 4029 } 4030 4031 // C99 6.5.16.1p1: the left operand is a pointer and the right is 4032 // a null pointer constant. 4033 if ((lhsType->isPointerType() || 4034 lhsType->isObjCObjectPointerType() || 4035 lhsType->isBlockPointerType()) 4036 && rExpr->isNullPointerConstant(Context, 4037 Expr::NPC_ValueDependentIsNull)) { 4038 ImpCastExprToType(rExpr, lhsType, CastExpr::CK_Unknown); 4039 return Compatible; 4040 } 4041 4042 // This check seems unnatural, however it is necessary to ensure the proper 4043 // conversion of functions/arrays. If the conversion were done for all 4044 // DeclExpr's (created by ActOnIdExpression), it would mess up the unary 4045 // expressions that surpress this implicit conversion (&, sizeof). 4046 // 4047 // Suppress this for references: C++ 8.5.3p5. 4048 if (!lhsType->isReferenceType()) 4049 DefaultFunctionArrayConversion(rExpr); 4050 4051 Sema::AssignConvertType result = 4052 CheckAssignmentConstraints(lhsType, rExpr->getType()); 4053 4054 // C99 6.5.16.1p2: The value of the right operand is converted to the 4055 // type of the assignment expression. 4056 // CheckAssignmentConstraints allows the left-hand side to be a reference, 4057 // so that we can use references in built-in functions even in C. 4058 // The getNonReferenceType() call makes sure that the resulting expression 4059 // does not have reference type. 4060 if (result != Incompatible && rExpr->getType() != lhsType) 4061 ImpCastExprToType(rExpr, lhsType.getNonReferenceType(), 4062 CastExpr::CK_Unknown); 4063 return result; 4064} 4065 4066QualType Sema::InvalidOperands(SourceLocation Loc, Expr *&lex, Expr *&rex) { 4067 Diag(Loc, diag::err_typecheck_invalid_operands) 4068 << lex->getType() << rex->getType() 4069 << lex->getSourceRange() << rex->getSourceRange(); 4070 return QualType(); 4071} 4072 4073inline QualType Sema::CheckVectorOperands(SourceLocation Loc, Expr *&lex, 4074 Expr *&rex) { 4075 // For conversion purposes, we ignore any qualifiers. 4076 // For example, "const float" and "float" are equivalent. 4077 QualType lhsType = 4078 Context.getCanonicalType(lex->getType()).getUnqualifiedType(); 4079 QualType rhsType = 4080 Context.getCanonicalType(rex->getType()).getUnqualifiedType(); 4081 4082 // If the vector types are identical, return. 4083 if (lhsType == rhsType) 4084 return lhsType; 4085 4086 // Handle the case of a vector & extvector type of the same size and element 4087 // type. It would be nice if we only had one vector type someday. 4088 if (getLangOptions().LaxVectorConversions) { 4089 // FIXME: Should we warn here? 4090 if (const VectorType *LV = lhsType->getAs<VectorType>()) { 4091 if (const VectorType *RV = rhsType->getAs<VectorType>()) 4092 if (LV->getElementType() == RV->getElementType() && 4093 LV->getNumElements() == RV->getNumElements()) { 4094 return lhsType->isExtVectorType() ? lhsType : rhsType; 4095 } 4096 } 4097 } 4098 4099 // Canonicalize the ExtVector to the LHS, remember if we swapped so we can 4100 // swap back (so that we don't reverse the inputs to a subtract, for instance. 4101 bool swapped = false; 4102 if (rhsType->isExtVectorType()) { 4103 swapped = true; 4104 std::swap(rex, lex); 4105 std::swap(rhsType, lhsType); 4106 } 4107 4108 // Handle the case of an ext vector and scalar. 4109 if (const ExtVectorType *LV = lhsType->getAs<ExtVectorType>()) { 4110 QualType EltTy = LV->getElementType(); 4111 if (EltTy->isIntegralType() && rhsType->isIntegralType()) { 4112 if (Context.getIntegerTypeOrder(EltTy, rhsType) >= 0) { 4113 ImpCastExprToType(rex, lhsType, CastExpr::CK_IntegralCast); 4114 if (swapped) std::swap(rex, lex); 4115 return lhsType; 4116 } 4117 } 4118 if (EltTy->isRealFloatingType() && rhsType->isScalarType() && 4119 rhsType->isRealFloatingType()) { 4120 if (Context.getFloatingTypeOrder(EltTy, rhsType) >= 0) { 4121 ImpCastExprToType(rex, lhsType, CastExpr::CK_FloatingCast); 4122 if (swapped) std::swap(rex, lex); 4123 return lhsType; 4124 } 4125 } 4126 } 4127 4128 // Vectors of different size or scalar and non-ext-vector are errors. 4129 Diag(Loc, diag::err_typecheck_vector_not_convertable) 4130 << lex->getType() << rex->getType() 4131 << lex->getSourceRange() << rex->getSourceRange(); 4132 return QualType(); 4133} 4134 4135inline QualType Sema::CheckMultiplyDivideOperands( 4136 Expr *&lex, Expr *&rex, SourceLocation Loc, bool isCompAssign) { 4137 if (lex->getType()->isVectorType() || rex->getType()->isVectorType()) 4138 return CheckVectorOperands(Loc, lex, rex); 4139 4140 QualType compType = UsualArithmeticConversions(lex, rex, isCompAssign); 4141 4142 if (lex->getType()->isArithmeticType() && rex->getType()->isArithmeticType()) 4143 return compType; 4144 return InvalidOperands(Loc, lex, rex); 4145} 4146 4147inline QualType Sema::CheckRemainderOperands( 4148 Expr *&lex, Expr *&rex, SourceLocation Loc, bool isCompAssign) { 4149 if (lex->getType()->isVectorType() || rex->getType()->isVectorType()) { 4150 if (lex->getType()->isIntegerType() && rex->getType()->isIntegerType()) 4151 return CheckVectorOperands(Loc, lex, rex); 4152 return InvalidOperands(Loc, lex, rex); 4153 } 4154 4155 QualType compType = UsualArithmeticConversions(lex, rex, isCompAssign); 4156 4157 if (lex->getType()->isIntegerType() && rex->getType()->isIntegerType()) 4158 return compType; 4159 return InvalidOperands(Loc, lex, rex); 4160} 4161 4162inline QualType Sema::CheckAdditionOperands( // C99 6.5.6 4163 Expr *&lex, Expr *&rex, SourceLocation Loc, QualType* CompLHSTy) { 4164 if (lex->getType()->isVectorType() || rex->getType()->isVectorType()) { 4165 QualType compType = CheckVectorOperands(Loc, lex, rex); 4166 if (CompLHSTy) *CompLHSTy = compType; 4167 return compType; 4168 } 4169 4170 QualType compType = UsualArithmeticConversions(lex, rex, CompLHSTy); 4171 4172 // handle the common case first (both operands are arithmetic). 4173 if (lex->getType()->isArithmeticType() && 4174 rex->getType()->isArithmeticType()) { 4175 if (CompLHSTy) *CompLHSTy = compType; 4176 return compType; 4177 } 4178 4179 // Put any potential pointer into PExp 4180 Expr* PExp = lex, *IExp = rex; 4181 if (IExp->getType()->isAnyPointerType()) 4182 std::swap(PExp, IExp); 4183 4184 if (PExp->getType()->isAnyPointerType()) { 4185 4186 if (IExp->getType()->isIntegerType()) { 4187 QualType PointeeTy = PExp->getType()->getPointeeType(); 4188 4189 // Check for arithmetic on pointers to incomplete types. 4190 if (PointeeTy->isVoidType()) { 4191 if (getLangOptions().CPlusPlus) { 4192 Diag(Loc, diag::err_typecheck_pointer_arith_void_type) 4193 << lex->getSourceRange() << rex->getSourceRange(); 4194 return QualType(); 4195 } 4196 4197 // GNU extension: arithmetic on pointer to void 4198 Diag(Loc, diag::ext_gnu_void_ptr) 4199 << lex->getSourceRange() << rex->getSourceRange(); 4200 } else if (PointeeTy->isFunctionType()) { 4201 if (getLangOptions().CPlusPlus) { 4202 Diag(Loc, diag::err_typecheck_pointer_arith_function_type) 4203 << lex->getType() << lex->getSourceRange(); 4204 return QualType(); 4205 } 4206 4207 // GNU extension: arithmetic on pointer to function 4208 Diag(Loc, diag::ext_gnu_ptr_func_arith) 4209 << lex->getType() << lex->getSourceRange(); 4210 } else { 4211 // Check if we require a complete type. 4212 if (((PExp->getType()->isPointerType() && 4213 !PExp->getType()->isDependentType()) || 4214 PExp->getType()->isObjCObjectPointerType()) && 4215 RequireCompleteType(Loc, PointeeTy, 4216 PDiag(diag::err_typecheck_arithmetic_incomplete_type) 4217 << PExp->getSourceRange() 4218 << PExp->getType())) 4219 return QualType(); 4220 } 4221 // Diagnose bad cases where we step over interface counts. 4222 if (PointeeTy->isObjCInterfaceType() && LangOpts.ObjCNonFragileABI) { 4223 Diag(Loc, diag::err_arithmetic_nonfragile_interface) 4224 << PointeeTy << PExp->getSourceRange(); 4225 return QualType(); 4226 } 4227 4228 if (CompLHSTy) { 4229 QualType LHSTy = Context.isPromotableBitField(lex); 4230 if (LHSTy.isNull()) { 4231 LHSTy = lex->getType(); 4232 if (LHSTy->isPromotableIntegerType()) 4233 LHSTy = Context.getPromotedIntegerType(LHSTy); 4234 } 4235 *CompLHSTy = LHSTy; 4236 } 4237 return PExp->getType(); 4238 } 4239 } 4240 4241 return InvalidOperands(Loc, lex, rex); 4242} 4243 4244// C99 6.5.6 4245QualType Sema::CheckSubtractionOperands(Expr *&lex, Expr *&rex, 4246 SourceLocation Loc, QualType* CompLHSTy) { 4247 if (lex->getType()->isVectorType() || rex->getType()->isVectorType()) { 4248 QualType compType = CheckVectorOperands(Loc, lex, rex); 4249 if (CompLHSTy) *CompLHSTy = compType; 4250 return compType; 4251 } 4252 4253 QualType compType = UsualArithmeticConversions(lex, rex, CompLHSTy); 4254 4255 // Enforce type constraints: C99 6.5.6p3. 4256 4257 // Handle the common case first (both operands are arithmetic). 4258 if (lex->getType()->isArithmeticType() 4259 && rex->getType()->isArithmeticType()) { 4260 if (CompLHSTy) *CompLHSTy = compType; 4261 return compType; 4262 } 4263 4264 // Either ptr - int or ptr - ptr. 4265 if (lex->getType()->isAnyPointerType()) { 4266 QualType lpointee = lex->getType()->getPointeeType(); 4267 4268 // The LHS must be an completely-defined object type. 4269 4270 bool ComplainAboutVoid = false; 4271 Expr *ComplainAboutFunc = 0; 4272 if (lpointee->isVoidType()) { 4273 if (getLangOptions().CPlusPlus) { 4274 Diag(Loc, diag::err_typecheck_pointer_arith_void_type) 4275 << lex->getSourceRange() << rex->getSourceRange(); 4276 return QualType(); 4277 } 4278 4279 // GNU C extension: arithmetic on pointer to void 4280 ComplainAboutVoid = true; 4281 } else if (lpointee->isFunctionType()) { 4282 if (getLangOptions().CPlusPlus) { 4283 Diag(Loc, diag::err_typecheck_pointer_arith_function_type) 4284 << lex->getType() << lex->getSourceRange(); 4285 return QualType(); 4286 } 4287 4288 // GNU C extension: arithmetic on pointer to function 4289 ComplainAboutFunc = lex; 4290 } else if (!lpointee->isDependentType() && 4291 RequireCompleteType(Loc, lpointee, 4292 PDiag(diag::err_typecheck_sub_ptr_object) 4293 << lex->getSourceRange() 4294 << lex->getType())) 4295 return QualType(); 4296 4297 // Diagnose bad cases where we step over interface counts. 4298 if (lpointee->isObjCInterfaceType() && LangOpts.ObjCNonFragileABI) { 4299 Diag(Loc, diag::err_arithmetic_nonfragile_interface) 4300 << lpointee << lex->getSourceRange(); 4301 return QualType(); 4302 } 4303 4304 // The result type of a pointer-int computation is the pointer type. 4305 if (rex->getType()->isIntegerType()) { 4306 if (ComplainAboutVoid) 4307 Diag(Loc, diag::ext_gnu_void_ptr) 4308 << lex->getSourceRange() << rex->getSourceRange(); 4309 if (ComplainAboutFunc) 4310 Diag(Loc, diag::ext_gnu_ptr_func_arith) 4311 << ComplainAboutFunc->getType() 4312 << ComplainAboutFunc->getSourceRange(); 4313 4314 if (CompLHSTy) *CompLHSTy = lex->getType(); 4315 return lex->getType(); 4316 } 4317 4318 // Handle pointer-pointer subtractions. 4319 if (const PointerType *RHSPTy = rex->getType()->getAs<PointerType>()) { 4320 QualType rpointee = RHSPTy->getPointeeType(); 4321 4322 // RHS must be a completely-type object type. 4323 // Handle the GNU void* extension. 4324 if (rpointee->isVoidType()) { 4325 if (getLangOptions().CPlusPlus) { 4326 Diag(Loc, diag::err_typecheck_pointer_arith_void_type) 4327 << lex->getSourceRange() << rex->getSourceRange(); 4328 return QualType(); 4329 } 4330 4331 ComplainAboutVoid = true; 4332 } else if (rpointee->isFunctionType()) { 4333 if (getLangOptions().CPlusPlus) { 4334 Diag(Loc, diag::err_typecheck_pointer_arith_function_type) 4335 << rex->getType() << rex->getSourceRange(); 4336 return QualType(); 4337 } 4338 4339 // GNU extension: arithmetic on pointer to function 4340 if (!ComplainAboutFunc) 4341 ComplainAboutFunc = rex; 4342 } else if (!rpointee->isDependentType() && 4343 RequireCompleteType(Loc, rpointee, 4344 PDiag(diag::err_typecheck_sub_ptr_object) 4345 << rex->getSourceRange() 4346 << rex->getType())) 4347 return QualType(); 4348 4349 if (getLangOptions().CPlusPlus) { 4350 // Pointee types must be the same: C++ [expr.add] 4351 if (!Context.hasSameUnqualifiedType(lpointee, rpointee)) { 4352 Diag(Loc, diag::err_typecheck_sub_ptr_compatible) 4353 << lex->getType() << rex->getType() 4354 << lex->getSourceRange() << rex->getSourceRange(); 4355 return QualType(); 4356 } 4357 } else { 4358 // Pointee types must be compatible C99 6.5.6p3 4359 if (!Context.typesAreCompatible( 4360 Context.getCanonicalType(lpointee).getUnqualifiedType(), 4361 Context.getCanonicalType(rpointee).getUnqualifiedType())) { 4362 Diag(Loc, diag::err_typecheck_sub_ptr_compatible) 4363 << lex->getType() << rex->getType() 4364 << lex->getSourceRange() << rex->getSourceRange(); 4365 return QualType(); 4366 } 4367 } 4368 4369 if (ComplainAboutVoid) 4370 Diag(Loc, diag::ext_gnu_void_ptr) 4371 << lex->getSourceRange() << rex->getSourceRange(); 4372 if (ComplainAboutFunc) 4373 Diag(Loc, diag::ext_gnu_ptr_func_arith) 4374 << ComplainAboutFunc->getType() 4375 << ComplainAboutFunc->getSourceRange(); 4376 4377 if (CompLHSTy) *CompLHSTy = lex->getType(); 4378 return Context.getPointerDiffType(); 4379 } 4380 } 4381 4382 return InvalidOperands(Loc, lex, rex); 4383} 4384 4385// C99 6.5.7 4386QualType Sema::CheckShiftOperands(Expr *&lex, Expr *&rex, SourceLocation Loc, 4387 bool isCompAssign) { 4388 // C99 6.5.7p2: Each of the operands shall have integer type. 4389 if (!lex->getType()->isIntegerType() || !rex->getType()->isIntegerType()) 4390 return InvalidOperands(Loc, lex, rex); 4391 4392 // Vector shifts promote their scalar inputs to vector type. 4393 if (lex->getType()->isVectorType() || rex->getType()->isVectorType()) 4394 return CheckVectorOperands(Loc, lex, rex); 4395 4396 // Shifts don't perform usual arithmetic conversions, they just do integer 4397 // promotions on each operand. C99 6.5.7p3 4398 QualType LHSTy = Context.isPromotableBitField(lex); 4399 if (LHSTy.isNull()) { 4400 LHSTy = lex->getType(); 4401 if (LHSTy->isPromotableIntegerType()) 4402 LHSTy = Context.getPromotedIntegerType(LHSTy); 4403 } 4404 if (!isCompAssign) 4405 ImpCastExprToType(lex, LHSTy, CastExpr::CK_IntegralCast); 4406 4407 UsualUnaryConversions(rex); 4408 4409 // Sanity-check shift operands 4410 llvm::APSInt Right; 4411 // Check right/shifter operand 4412 if (!rex->isValueDependent() && 4413 rex->isIntegerConstantExpr(Right, Context)) { 4414 if (Right.isNegative()) 4415 Diag(Loc, diag::warn_shift_negative) << rex->getSourceRange(); 4416 else { 4417 llvm::APInt LeftBits(Right.getBitWidth(), 4418 Context.getTypeSize(lex->getType())); 4419 if (Right.uge(LeftBits)) 4420 Diag(Loc, diag::warn_shift_gt_typewidth) << rex->getSourceRange(); 4421 } 4422 } 4423 4424 // "The type of the result is that of the promoted left operand." 4425 return LHSTy; 4426} 4427 4428/// \brief Implements -Wsign-compare. 4429/// 4430/// \param lex the left-hand expression 4431/// \param rex the right-hand expression 4432/// \param OpLoc the location of the joining operator 4433/// \param Equality whether this is an "equality-like" join, which 4434/// suppresses the warning in some cases 4435void Sema::CheckSignCompare(Expr *lex, Expr *rex, SourceLocation OpLoc, 4436 const PartialDiagnostic &PD, bool Equality) { 4437 // Don't warn if we're in an unevaluated context. 4438 if (ExprEvalContext == Unevaluated) 4439 return; 4440 4441 QualType lt = lex->getType(), rt = rex->getType(); 4442 4443 // Only warn if both operands are integral. 4444 if (!lt->isIntegerType() || !rt->isIntegerType()) 4445 return; 4446 4447 // If either expression is value-dependent, don't warn. We'll get another 4448 // chance at instantiation time. 4449 if (lex->isValueDependent() || rex->isValueDependent()) 4450 return; 4451 4452 // The rule is that the signed operand becomes unsigned, so isolate the 4453 // signed operand. 4454 Expr *signedOperand, *unsignedOperand; 4455 if (lt->isSignedIntegerType()) { 4456 if (rt->isSignedIntegerType()) return; 4457 signedOperand = lex; 4458 unsignedOperand = rex; 4459 } else { 4460 if (!rt->isSignedIntegerType()) return; 4461 signedOperand = rex; 4462 unsignedOperand = lex; 4463 } 4464 4465 // If the unsigned type is strictly smaller than the signed type, 4466 // then (1) the result type will be signed and (2) the unsigned 4467 // value will fit fully within the signed type, and thus the result 4468 // of the comparison will be exact. 4469 if (Context.getIntWidth(signedOperand->getType()) > 4470 Context.getIntWidth(unsignedOperand->getType())) 4471 return; 4472 4473 // If the value is a non-negative integer constant, then the 4474 // signed->unsigned conversion won't change it. 4475 llvm::APSInt value; 4476 if (signedOperand->isIntegerConstantExpr(value, Context)) { 4477 assert(value.isSigned() && "result of signed expression not signed"); 4478 4479 if (value.isNonNegative()) 4480 return; 4481 } 4482 4483 if (Equality) { 4484 // For (in)equality comparisons, if the unsigned operand is a 4485 // constant which cannot collide with a overflowed signed operand, 4486 // then reinterpreting the signed operand as unsigned will not 4487 // change the result of the comparison. 4488 if (unsignedOperand->isIntegerConstantExpr(value, Context)) { 4489 assert(!value.isSigned() && "result of unsigned expression is signed"); 4490 4491 // 2's complement: test the top bit. 4492 if (value.isNonNegative()) 4493 return; 4494 } 4495 } 4496 4497 Diag(OpLoc, PD) 4498 << lex->getType() << rex->getType() 4499 << lex->getSourceRange() << rex->getSourceRange(); 4500} 4501 4502// C99 6.5.8, C++ [expr.rel] 4503QualType Sema::CheckCompareOperands(Expr *&lex, Expr *&rex, SourceLocation Loc, 4504 unsigned OpaqueOpc, bool isRelational) { 4505 BinaryOperator::Opcode Opc = (BinaryOperator::Opcode)OpaqueOpc; 4506 4507 if (lex->getType()->isVectorType() || rex->getType()->isVectorType()) 4508 return CheckVectorCompareOperands(lex, rex, Loc, isRelational); 4509 4510 CheckSignCompare(lex, rex, Loc, diag::warn_mixed_sign_comparison, 4511 (Opc == BinaryOperator::EQ || Opc == BinaryOperator::NE)); 4512 4513 // C99 6.5.8p3 / C99 6.5.9p4 4514 if (lex->getType()->isArithmeticType() && rex->getType()->isArithmeticType()) 4515 UsualArithmeticConversions(lex, rex); 4516 else { 4517 UsualUnaryConversions(lex); 4518 UsualUnaryConversions(rex); 4519 } 4520 QualType lType = lex->getType(); 4521 QualType rType = rex->getType(); 4522 4523 if (!lType->isFloatingType() 4524 && !(lType->isBlockPointerType() && isRelational)) { 4525 // For non-floating point types, check for self-comparisons of the form 4526 // x == x, x != x, x < x, etc. These always evaluate to a constant, and 4527 // often indicate logic errors in the program. 4528 // NOTE: Don't warn about comparisons of enum constants. These can arise 4529 // from macro expansions, and are usually quite deliberate. 4530 Expr *LHSStripped = lex->IgnoreParens(); 4531 Expr *RHSStripped = rex->IgnoreParens(); 4532 if (DeclRefExpr* DRL = dyn_cast<DeclRefExpr>(LHSStripped)) 4533 if (DeclRefExpr* DRR = dyn_cast<DeclRefExpr>(RHSStripped)) 4534 if (DRL->getDecl() == DRR->getDecl() && 4535 !isa<EnumConstantDecl>(DRL->getDecl())) 4536 Diag(Loc, diag::warn_selfcomparison); 4537 4538 if (isa<CastExpr>(LHSStripped)) 4539 LHSStripped = LHSStripped->IgnoreParenCasts(); 4540 if (isa<CastExpr>(RHSStripped)) 4541 RHSStripped = RHSStripped->IgnoreParenCasts(); 4542 4543 // Warn about comparisons against a string constant (unless the other 4544 // operand is null), the user probably wants strcmp. 4545 Expr *literalString = 0; 4546 Expr *literalStringStripped = 0; 4547 if ((isa<StringLiteral>(LHSStripped) || isa<ObjCEncodeExpr>(LHSStripped)) && 4548 !RHSStripped->isNullPointerConstant(Context, 4549 Expr::NPC_ValueDependentIsNull)) { 4550 literalString = lex; 4551 literalStringStripped = LHSStripped; 4552 } else if ((isa<StringLiteral>(RHSStripped) || 4553 isa<ObjCEncodeExpr>(RHSStripped)) && 4554 !LHSStripped->isNullPointerConstant(Context, 4555 Expr::NPC_ValueDependentIsNull)) { 4556 literalString = rex; 4557 literalStringStripped = RHSStripped; 4558 } 4559 4560 if (literalString) { 4561 std::string resultComparison; 4562 switch (Opc) { 4563 case BinaryOperator::LT: resultComparison = ") < 0"; break; 4564 case BinaryOperator::GT: resultComparison = ") > 0"; break; 4565 case BinaryOperator::LE: resultComparison = ") <= 0"; break; 4566 case BinaryOperator::GE: resultComparison = ") >= 0"; break; 4567 case BinaryOperator::EQ: resultComparison = ") == 0"; break; 4568 case BinaryOperator::NE: resultComparison = ") != 0"; break; 4569 default: assert(false && "Invalid comparison operator"); 4570 } 4571 Diag(Loc, diag::warn_stringcompare) 4572 << isa<ObjCEncodeExpr>(literalStringStripped) 4573 << literalString->getSourceRange() 4574 << CodeModificationHint::CreateReplacement(SourceRange(Loc), ", ") 4575 << CodeModificationHint::CreateInsertion(lex->getLocStart(), 4576 "strcmp(") 4577 << CodeModificationHint::CreateInsertion( 4578 PP.getLocForEndOfToken(rex->getLocEnd()), 4579 resultComparison); 4580 } 4581 } 4582 4583 // The result of comparisons is 'bool' in C++, 'int' in C. 4584 QualType ResultTy = getLangOptions().CPlusPlus? Context.BoolTy :Context.IntTy; 4585 4586 if (isRelational) { 4587 if (lType->isRealType() && rType->isRealType()) 4588 return ResultTy; 4589 } else { 4590 // Check for comparisons of floating point operands using != and ==. 4591 if (lType->isFloatingType()) { 4592 assert(rType->isFloatingType()); 4593 CheckFloatComparison(Loc,lex,rex); 4594 } 4595 4596 if (lType->isArithmeticType() && rType->isArithmeticType()) 4597 return ResultTy; 4598 } 4599 4600 bool LHSIsNull = lex->isNullPointerConstant(Context, 4601 Expr::NPC_ValueDependentIsNull); 4602 bool RHSIsNull = rex->isNullPointerConstant(Context, 4603 Expr::NPC_ValueDependentIsNull); 4604 4605 // All of the following pointer related warnings are GCC extensions, except 4606 // when handling null pointer constants. One day, we can consider making them 4607 // errors (when -pedantic-errors is enabled). 4608 if (lType->isPointerType() && rType->isPointerType()) { // C99 6.5.8p2 4609 QualType LCanPointeeTy = 4610 Context.getCanonicalType(lType->getAs<PointerType>()->getPointeeType()); 4611 QualType RCanPointeeTy = 4612 Context.getCanonicalType(rType->getAs<PointerType>()->getPointeeType()); 4613 4614 if (getLangOptions().CPlusPlus) { 4615 if (LCanPointeeTy == RCanPointeeTy) 4616 return ResultTy; 4617 4618 // C++ [expr.rel]p2: 4619 // [...] Pointer conversions (4.10) and qualification 4620 // conversions (4.4) are performed on pointer operands (or on 4621 // a pointer operand and a null pointer constant) to bring 4622 // them to their composite pointer type. [...] 4623 // 4624 // C++ [expr.eq]p1 uses the same notion for (in)equality 4625 // comparisons of pointers. 4626 QualType T = FindCompositePointerType(lex, rex); 4627 if (T.isNull()) { 4628 Diag(Loc, diag::err_typecheck_comparison_of_distinct_pointers) 4629 << lType << rType << lex->getSourceRange() << rex->getSourceRange(); 4630 return QualType(); 4631 } 4632 4633 ImpCastExprToType(lex, T, CastExpr::CK_BitCast); 4634 ImpCastExprToType(rex, T, CastExpr::CK_BitCast); 4635 return ResultTy; 4636 } 4637 // C99 6.5.9p2 and C99 6.5.8p2 4638 if (Context.typesAreCompatible(LCanPointeeTy.getUnqualifiedType(), 4639 RCanPointeeTy.getUnqualifiedType())) { 4640 // Valid unless a relational comparison of function pointers 4641 if (isRelational && LCanPointeeTy->isFunctionType()) { 4642 Diag(Loc, diag::ext_typecheck_ordered_comparison_of_function_pointers) 4643 << lType << rType << lex->getSourceRange() << rex->getSourceRange(); 4644 } 4645 } else if (!isRelational && 4646 (LCanPointeeTy->isVoidType() || RCanPointeeTy->isVoidType())) { 4647 // Valid unless comparison between non-null pointer and function pointer 4648 if ((LCanPointeeTy->isFunctionType() || RCanPointeeTy->isFunctionType()) 4649 && !LHSIsNull && !RHSIsNull) { 4650 Diag(Loc, diag::ext_typecheck_comparison_of_fptr_to_void) 4651 << lType << rType << lex->getSourceRange() << rex->getSourceRange(); 4652 } 4653 } else { 4654 // Invalid 4655 Diag(Loc, diag::ext_typecheck_comparison_of_distinct_pointers) 4656 << lType << rType << lex->getSourceRange() << rex->getSourceRange(); 4657 } 4658 if (LCanPointeeTy != RCanPointeeTy) 4659 ImpCastExprToType(rex, lType, CastExpr::CK_BitCast); 4660 return ResultTy; 4661 } 4662 4663 if (getLangOptions().CPlusPlus) { 4664 // Comparison of pointers with null pointer constants and equality 4665 // comparisons of member pointers to null pointer constants. 4666 if (RHSIsNull && 4667 (lType->isPointerType() || 4668 (!isRelational && lType->isMemberPointerType()))) { 4669 ImpCastExprToType(rex, lType, CastExpr::CK_NullToMemberPointer); 4670 return ResultTy; 4671 } 4672 if (LHSIsNull && 4673 (rType->isPointerType() || 4674 (!isRelational && rType->isMemberPointerType()))) { 4675 ImpCastExprToType(lex, rType, CastExpr::CK_NullToMemberPointer); 4676 return ResultTy; 4677 } 4678 4679 // Comparison of member pointers. 4680 if (!isRelational && 4681 lType->isMemberPointerType() && rType->isMemberPointerType()) { 4682 // C++ [expr.eq]p2: 4683 // In addition, pointers to members can be compared, or a pointer to 4684 // member and a null pointer constant. Pointer to member conversions 4685 // (4.11) and qualification conversions (4.4) are performed to bring 4686 // them to a common type. If one operand is a null pointer constant, 4687 // the common type is the type of the other operand. Otherwise, the 4688 // common type is a pointer to member type similar (4.4) to the type 4689 // of one of the operands, with a cv-qualification signature (4.4) 4690 // that is the union of the cv-qualification signatures of the operand 4691 // types. 4692 QualType T = FindCompositePointerType(lex, rex); 4693 if (T.isNull()) { 4694 Diag(Loc, diag::err_typecheck_comparison_of_distinct_pointers) 4695 << lType << rType << lex->getSourceRange() << rex->getSourceRange(); 4696 return QualType(); 4697 } 4698 4699 ImpCastExprToType(lex, T, CastExpr::CK_BitCast); 4700 ImpCastExprToType(rex, T, CastExpr::CK_BitCast); 4701 return ResultTy; 4702 } 4703 4704 // Comparison of nullptr_t with itself. 4705 if (lType->isNullPtrType() && rType->isNullPtrType()) 4706 return ResultTy; 4707 } 4708 4709 // Handle block pointer types. 4710 if (!isRelational && lType->isBlockPointerType() && rType->isBlockPointerType()) { 4711 QualType lpointee = lType->getAs<BlockPointerType>()->getPointeeType(); 4712 QualType rpointee = rType->getAs<BlockPointerType>()->getPointeeType(); 4713 4714 if (!LHSIsNull && !RHSIsNull && 4715 !Context.typesAreCompatible(lpointee, rpointee)) { 4716 Diag(Loc, diag::err_typecheck_comparison_of_distinct_blocks) 4717 << lType << rType << lex->getSourceRange() << rex->getSourceRange(); 4718 } 4719 ImpCastExprToType(rex, lType, CastExpr::CK_BitCast); 4720 return ResultTy; 4721 } 4722 // Allow block pointers to be compared with null pointer constants. 4723 if (!isRelational 4724 && ((lType->isBlockPointerType() && rType->isPointerType()) 4725 || (lType->isPointerType() && rType->isBlockPointerType()))) { 4726 if (!LHSIsNull && !RHSIsNull) { 4727 if (!((rType->isPointerType() && rType->getAs<PointerType>() 4728 ->getPointeeType()->isVoidType()) 4729 || (lType->isPointerType() && lType->getAs<PointerType>() 4730 ->getPointeeType()->isVoidType()))) 4731 Diag(Loc, diag::err_typecheck_comparison_of_distinct_blocks) 4732 << lType << rType << lex->getSourceRange() << rex->getSourceRange(); 4733 } 4734 ImpCastExprToType(rex, lType, CastExpr::CK_BitCast); 4735 return ResultTy; 4736 } 4737 4738 if ((lType->isObjCObjectPointerType() || rType->isObjCObjectPointerType())) { 4739 if (lType->isPointerType() || rType->isPointerType()) { 4740 const PointerType *LPT = lType->getAs<PointerType>(); 4741 const PointerType *RPT = rType->getAs<PointerType>(); 4742 bool LPtrToVoid = LPT ? 4743 Context.getCanonicalType(LPT->getPointeeType())->isVoidType() : false; 4744 bool RPtrToVoid = RPT ? 4745 Context.getCanonicalType(RPT->getPointeeType())->isVoidType() : false; 4746 4747 if (!LPtrToVoid && !RPtrToVoid && 4748 !Context.typesAreCompatible(lType, rType)) { 4749 Diag(Loc, diag::ext_typecheck_comparison_of_distinct_pointers) 4750 << lType << rType << lex->getSourceRange() << rex->getSourceRange(); 4751 } 4752 ImpCastExprToType(rex, lType, CastExpr::CK_BitCast); 4753 return ResultTy; 4754 } 4755 if (lType->isObjCObjectPointerType() && rType->isObjCObjectPointerType()) { 4756 if (!Context.areComparableObjCPointerTypes(lType, rType)) 4757 Diag(Loc, diag::ext_typecheck_comparison_of_distinct_pointers) 4758 << lType << rType << lex->getSourceRange() << rex->getSourceRange(); 4759 ImpCastExprToType(rex, lType, CastExpr::CK_BitCast); 4760 return ResultTy; 4761 } 4762 } 4763 if (lType->isAnyPointerType() && rType->isIntegerType()) { 4764 unsigned DiagID = 0; 4765 if (RHSIsNull) { 4766 if (isRelational) 4767 DiagID = diag::ext_typecheck_ordered_comparison_of_pointer_and_zero; 4768 } else if (isRelational) 4769 DiagID = diag::ext_typecheck_ordered_comparison_of_pointer_integer; 4770 else 4771 DiagID = diag::ext_typecheck_comparison_of_pointer_integer; 4772 4773 if (DiagID) { 4774 Diag(Loc, DiagID) 4775 << lType << rType << lex->getSourceRange() << rex->getSourceRange(); 4776 } 4777 ImpCastExprToType(rex, lType, CastExpr::CK_IntegralToPointer); 4778 return ResultTy; 4779 } 4780 if (lType->isIntegerType() && rType->isAnyPointerType()) { 4781 unsigned DiagID = 0; 4782 if (LHSIsNull) { 4783 if (isRelational) 4784 DiagID = diag::ext_typecheck_ordered_comparison_of_pointer_and_zero; 4785 } else if (isRelational) 4786 DiagID = diag::ext_typecheck_ordered_comparison_of_pointer_integer; 4787 else 4788 DiagID = diag::ext_typecheck_comparison_of_pointer_integer; 4789 4790 if (DiagID) { 4791 Diag(Loc, DiagID) 4792 << lType << rType << lex->getSourceRange() << rex->getSourceRange(); 4793 } 4794 ImpCastExprToType(lex, rType, CastExpr::CK_IntegralToPointer); 4795 return ResultTy; 4796 } 4797 // Handle block pointers. 4798 if (!isRelational && RHSIsNull 4799 && lType->isBlockPointerType() && rType->isIntegerType()) { 4800 ImpCastExprToType(rex, lType, CastExpr::CK_IntegralToPointer); 4801 return ResultTy; 4802 } 4803 if (!isRelational && LHSIsNull 4804 && lType->isIntegerType() && rType->isBlockPointerType()) { 4805 ImpCastExprToType(lex, rType, CastExpr::CK_IntegralToPointer); 4806 return ResultTy; 4807 } 4808 return InvalidOperands(Loc, lex, rex); 4809} 4810 4811/// CheckVectorCompareOperands - vector comparisons are a clang extension that 4812/// operates on extended vector types. Instead of producing an IntTy result, 4813/// like a scalar comparison, a vector comparison produces a vector of integer 4814/// types. 4815QualType Sema::CheckVectorCompareOperands(Expr *&lex, Expr *&rex, 4816 SourceLocation Loc, 4817 bool isRelational) { 4818 // Check to make sure we're operating on vectors of the same type and width, 4819 // Allowing one side to be a scalar of element type. 4820 QualType vType = CheckVectorOperands(Loc, lex, rex); 4821 if (vType.isNull()) 4822 return vType; 4823 4824 QualType lType = lex->getType(); 4825 QualType rType = rex->getType(); 4826 4827 // For non-floating point types, check for self-comparisons of the form 4828 // x == x, x != x, x < x, etc. These always evaluate to a constant, and 4829 // often indicate logic errors in the program. 4830 if (!lType->isFloatingType()) { 4831 if (DeclRefExpr* DRL = dyn_cast<DeclRefExpr>(lex->IgnoreParens())) 4832 if (DeclRefExpr* DRR = dyn_cast<DeclRefExpr>(rex->IgnoreParens())) 4833 if (DRL->getDecl() == DRR->getDecl()) 4834 Diag(Loc, diag::warn_selfcomparison); 4835 } 4836 4837 // Check for comparisons of floating point operands using != and ==. 4838 if (!isRelational && lType->isFloatingType()) { 4839 assert (rType->isFloatingType()); 4840 CheckFloatComparison(Loc,lex,rex); 4841 } 4842 4843 // Return the type for the comparison, which is the same as vector type for 4844 // integer vectors, or an integer type of identical size and number of 4845 // elements for floating point vectors. 4846 if (lType->isIntegerType()) 4847 return lType; 4848 4849 const VectorType *VTy = lType->getAs<VectorType>(); 4850 unsigned TypeSize = Context.getTypeSize(VTy->getElementType()); 4851 if (TypeSize == Context.getTypeSize(Context.IntTy)) 4852 return Context.getExtVectorType(Context.IntTy, VTy->getNumElements()); 4853 if (TypeSize == Context.getTypeSize(Context.LongTy)) 4854 return Context.getExtVectorType(Context.LongTy, VTy->getNumElements()); 4855 4856 assert(TypeSize == Context.getTypeSize(Context.LongLongTy) && 4857 "Unhandled vector element size in vector compare"); 4858 return Context.getExtVectorType(Context.LongLongTy, VTy->getNumElements()); 4859} 4860 4861inline QualType Sema::CheckBitwiseOperands( 4862 Expr *&lex, Expr *&rex, SourceLocation Loc, bool isCompAssign) { 4863 if (lex->getType()->isVectorType() || rex->getType()->isVectorType()) 4864 return CheckVectorOperands(Loc, lex, rex); 4865 4866 QualType compType = UsualArithmeticConversions(lex, rex, isCompAssign); 4867 4868 if (lex->getType()->isIntegerType() && rex->getType()->isIntegerType()) 4869 return compType; 4870 return InvalidOperands(Loc, lex, rex); 4871} 4872 4873inline QualType Sema::CheckLogicalOperands( // C99 6.5.[13,14] 4874 Expr *&lex, Expr *&rex, SourceLocation Loc) { 4875 if (!Context.getLangOptions().CPlusPlus) { 4876 UsualUnaryConversions(lex); 4877 UsualUnaryConversions(rex); 4878 4879 if (!lex->getType()->isScalarType() || !rex->getType()->isScalarType()) 4880 return InvalidOperands(Loc, lex, rex); 4881 4882 return Context.IntTy; 4883 } 4884 4885 // C++ [expr.log.and]p1 4886 // C++ [expr.log.or]p1 4887 // The operands are both implicitly converted to type bool (clause 4). 4888 StandardConversionSequence LHS; 4889 if (!IsStandardConversion(lex, Context.BoolTy, 4890 /*InOverloadResolution=*/false, LHS)) 4891 return InvalidOperands(Loc, lex, rex); 4892 4893 if (PerformImplicitConversion(lex, Context.BoolTy, LHS, 4894 "passing", /*IgnoreBaseAccess=*/false)) 4895 return InvalidOperands(Loc, lex, rex); 4896 4897 StandardConversionSequence RHS; 4898 if (!IsStandardConversion(rex, Context.BoolTy, 4899 /*InOverloadResolution=*/false, RHS)) 4900 return InvalidOperands(Loc, lex, rex); 4901 4902 if (PerformImplicitConversion(rex, Context.BoolTy, RHS, 4903 "passing", /*IgnoreBaseAccess=*/false)) 4904 return InvalidOperands(Loc, lex, rex); 4905 4906 // C++ [expr.log.and]p2 4907 // C++ [expr.log.or]p2 4908 // The result is a bool. 4909 return Context.BoolTy; 4910} 4911 4912/// IsReadonlyProperty - Verify that otherwise a valid l-value expression 4913/// is a read-only property; return true if so. A readonly property expression 4914/// depends on various declarations and thus must be treated specially. 4915/// 4916static bool IsReadonlyProperty(Expr *E, Sema &S) { 4917 if (E->getStmtClass() == Expr::ObjCPropertyRefExprClass) { 4918 const ObjCPropertyRefExpr* PropExpr = cast<ObjCPropertyRefExpr>(E); 4919 if (ObjCPropertyDecl *PDecl = PropExpr->getProperty()) { 4920 QualType BaseType = PropExpr->getBase()->getType(); 4921 if (const ObjCObjectPointerType *OPT = 4922 BaseType->getAsObjCInterfacePointerType()) 4923 if (ObjCInterfaceDecl *IFace = OPT->getInterfaceDecl()) 4924 if (S.isPropertyReadonly(PDecl, IFace)) 4925 return true; 4926 } 4927 } 4928 return false; 4929} 4930 4931/// CheckForModifiableLvalue - Verify that E is a modifiable lvalue. If not, 4932/// emit an error and return true. If so, return false. 4933static bool CheckForModifiableLvalue(Expr *E, SourceLocation Loc, Sema &S) { 4934 SourceLocation OrigLoc = Loc; 4935 Expr::isModifiableLvalueResult IsLV = E->isModifiableLvalue(S.Context, 4936 &Loc); 4937 if (IsLV == Expr::MLV_Valid && IsReadonlyProperty(E, S)) 4938 IsLV = Expr::MLV_ReadonlyProperty; 4939 if (IsLV == Expr::MLV_Valid) 4940 return false; 4941 4942 unsigned Diag = 0; 4943 bool NeedType = false; 4944 switch (IsLV) { // C99 6.5.16p2 4945 default: assert(0 && "Unknown result from isModifiableLvalue!"); 4946 case Expr::MLV_ConstQualified: Diag = diag::err_typecheck_assign_const; break; 4947 case Expr::MLV_ArrayType: 4948 Diag = diag::err_typecheck_array_not_modifiable_lvalue; 4949 NeedType = true; 4950 break; 4951 case Expr::MLV_NotObjectType: 4952 Diag = diag::err_typecheck_non_object_not_modifiable_lvalue; 4953 NeedType = true; 4954 break; 4955 case Expr::MLV_LValueCast: 4956 Diag = diag::err_typecheck_lvalue_casts_not_supported; 4957 break; 4958 case Expr::MLV_InvalidExpression: 4959 Diag = diag::err_typecheck_expression_not_modifiable_lvalue; 4960 break; 4961 case Expr::MLV_IncompleteType: 4962 case Expr::MLV_IncompleteVoidType: 4963 return S.RequireCompleteType(Loc, E->getType(), 4964 PDiag(diag::err_typecheck_incomplete_type_not_modifiable_lvalue) 4965 << E->getSourceRange()); 4966 case Expr::MLV_DuplicateVectorComponents: 4967 Diag = diag::err_typecheck_duplicate_vector_components_not_mlvalue; 4968 break; 4969 case Expr::MLV_NotBlockQualified: 4970 Diag = diag::err_block_decl_ref_not_modifiable_lvalue; 4971 break; 4972 case Expr::MLV_ReadonlyProperty: 4973 Diag = diag::error_readonly_property_assignment; 4974 break; 4975 case Expr::MLV_NoSetterProperty: 4976 Diag = diag::error_nosetter_property_assignment; 4977 break; 4978 } 4979 4980 SourceRange Assign; 4981 if (Loc != OrigLoc) 4982 Assign = SourceRange(OrigLoc, OrigLoc); 4983 if (NeedType) 4984 S.Diag(Loc, Diag) << E->getType() << E->getSourceRange() << Assign; 4985 else 4986 S.Diag(Loc, Diag) << E->getSourceRange() << Assign; 4987 return true; 4988} 4989 4990 4991 4992// C99 6.5.16.1 4993QualType Sema::CheckAssignmentOperands(Expr *LHS, Expr *&RHS, 4994 SourceLocation Loc, 4995 QualType CompoundType) { 4996 // Verify that LHS is a modifiable lvalue, and emit error if not. 4997 if (CheckForModifiableLvalue(LHS, Loc, *this)) 4998 return QualType(); 4999 5000 QualType LHSType = LHS->getType(); 5001 QualType RHSType = CompoundType.isNull() ? RHS->getType() : CompoundType; 5002 5003 AssignConvertType ConvTy; 5004 if (CompoundType.isNull()) { 5005 // Simple assignment "x = y". 5006 ConvTy = CheckSingleAssignmentConstraints(LHSType, RHS); 5007 // Special case of NSObject attributes on c-style pointer types. 5008 if (ConvTy == IncompatiblePointer && 5009 ((Context.isObjCNSObjectType(LHSType) && 5010 RHSType->isObjCObjectPointerType()) || 5011 (Context.isObjCNSObjectType(RHSType) && 5012 LHSType->isObjCObjectPointerType()))) 5013 ConvTy = Compatible; 5014 5015 // If the RHS is a unary plus or minus, check to see if they = and + are 5016 // right next to each other. If so, the user may have typo'd "x =+ 4" 5017 // instead of "x += 4". 5018 Expr *RHSCheck = RHS; 5019 if (ImplicitCastExpr *ICE = dyn_cast<ImplicitCastExpr>(RHSCheck)) 5020 RHSCheck = ICE->getSubExpr(); 5021 if (UnaryOperator *UO = dyn_cast<UnaryOperator>(RHSCheck)) { 5022 if ((UO->getOpcode() == UnaryOperator::Plus || 5023 UO->getOpcode() == UnaryOperator::Minus) && 5024 Loc.isFileID() && UO->getOperatorLoc().isFileID() && 5025 // Only if the two operators are exactly adjacent. 5026 Loc.getFileLocWithOffset(1) == UO->getOperatorLoc() && 5027 // And there is a space or other character before the subexpr of the 5028 // unary +/-. We don't want to warn on "x=-1". 5029 Loc.getFileLocWithOffset(2) != UO->getSubExpr()->getLocStart() && 5030 UO->getSubExpr()->getLocStart().isFileID()) { 5031 Diag(Loc, diag::warn_not_compound_assign) 5032 << (UO->getOpcode() == UnaryOperator::Plus ? "+" : "-") 5033 << SourceRange(UO->getOperatorLoc(), UO->getOperatorLoc()); 5034 } 5035 } 5036 } else { 5037 // Compound assignment "x += y" 5038 ConvTy = CheckAssignmentConstraints(LHSType, RHSType); 5039 } 5040 5041 if (DiagnoseAssignmentResult(ConvTy, Loc, LHSType, RHSType, 5042 RHS, "assigning")) 5043 return QualType(); 5044 5045 // C99 6.5.16p3: The type of an assignment expression is the type of the 5046 // left operand unless the left operand has qualified type, in which case 5047 // it is the unqualified version of the type of the left operand. 5048 // C99 6.5.16.1p2: In simple assignment, the value of the right operand 5049 // is converted to the type of the assignment expression (above). 5050 // C++ 5.17p1: the type of the assignment expression is that of its left 5051 // operand. 5052 return LHSType.getUnqualifiedType(); 5053} 5054 5055// C99 6.5.17 5056QualType Sema::CheckCommaOperands(Expr *LHS, Expr *&RHS, SourceLocation Loc) { 5057 // Comma performs lvalue conversion (C99 6.3.2.1), but not unary conversions. 5058 DefaultFunctionArrayConversion(RHS); 5059 5060 // FIXME: Check that RHS type is complete in C mode (it's legal for it to be 5061 // incomplete in C++). 5062 5063 return RHS->getType(); 5064} 5065 5066/// CheckIncrementDecrementOperand - unlike most "Check" methods, this routine 5067/// doesn't need to call UsualUnaryConversions or UsualArithmeticConversions. 5068QualType Sema::CheckIncrementDecrementOperand(Expr *Op, SourceLocation OpLoc, 5069 bool isInc) { 5070 if (Op->isTypeDependent()) 5071 return Context.DependentTy; 5072 5073 QualType ResType = Op->getType(); 5074 assert(!ResType.isNull() && "no type for increment/decrement expression"); 5075 5076 if (getLangOptions().CPlusPlus && ResType->isBooleanType()) { 5077 // Decrement of bool is not allowed. 5078 if (!isInc) { 5079 Diag(OpLoc, diag::err_decrement_bool) << Op->getSourceRange(); 5080 return QualType(); 5081 } 5082 // Increment of bool sets it to true, but is deprecated. 5083 Diag(OpLoc, diag::warn_increment_bool) << Op->getSourceRange(); 5084 } else if (ResType->isRealType()) { 5085 // OK! 5086 } else if (ResType->isAnyPointerType()) { 5087 QualType PointeeTy = ResType->getPointeeType(); 5088 5089 // C99 6.5.2.4p2, 6.5.6p2 5090 if (PointeeTy->isVoidType()) { 5091 if (getLangOptions().CPlusPlus) { 5092 Diag(OpLoc, diag::err_typecheck_pointer_arith_void_type) 5093 << Op->getSourceRange(); 5094 return QualType(); 5095 } 5096 5097 // Pointer to void is a GNU extension in C. 5098 Diag(OpLoc, diag::ext_gnu_void_ptr) << Op->getSourceRange(); 5099 } else if (PointeeTy->isFunctionType()) { 5100 if (getLangOptions().CPlusPlus) { 5101 Diag(OpLoc, diag::err_typecheck_pointer_arith_function_type) 5102 << Op->getType() << Op->getSourceRange(); 5103 return QualType(); 5104 } 5105 5106 Diag(OpLoc, diag::ext_gnu_ptr_func_arith) 5107 << ResType << Op->getSourceRange(); 5108 } else if (RequireCompleteType(OpLoc, PointeeTy, 5109 PDiag(diag::err_typecheck_arithmetic_incomplete_type) 5110 << Op->getSourceRange() 5111 << ResType)) 5112 return QualType(); 5113 // Diagnose bad cases where we step over interface counts. 5114 else if (PointeeTy->isObjCInterfaceType() && LangOpts.ObjCNonFragileABI) { 5115 Diag(OpLoc, diag::err_arithmetic_nonfragile_interface) 5116 << PointeeTy << Op->getSourceRange(); 5117 return QualType(); 5118 } 5119 } else if (ResType->isComplexType()) { 5120 // C99 does not support ++/-- on complex types, we allow as an extension. 5121 Diag(OpLoc, diag::ext_integer_increment_complex) 5122 << ResType << Op->getSourceRange(); 5123 } else { 5124 Diag(OpLoc, diag::err_typecheck_illegal_increment_decrement) 5125 << ResType << Op->getSourceRange(); 5126 return QualType(); 5127 } 5128 // At this point, we know we have a real, complex or pointer type. 5129 // Now make sure the operand is a modifiable lvalue. 5130 if (CheckForModifiableLvalue(Op, OpLoc, *this)) 5131 return QualType(); 5132 return ResType; 5133} 5134 5135/// getPrimaryDecl - Helper function for CheckAddressOfOperand(). 5136/// This routine allows us to typecheck complex/recursive expressions 5137/// where the declaration is needed for type checking. We only need to 5138/// handle cases when the expression references a function designator 5139/// or is an lvalue. Here are some examples: 5140/// - &(x) => x 5141/// - &*****f => f for f a function designator. 5142/// - &s.xx => s 5143/// - &s.zz[1].yy -> s, if zz is an array 5144/// - *(x + 1) -> x, if x is an array 5145/// - &"123"[2] -> 0 5146/// - & __real__ x -> x 5147static NamedDecl *getPrimaryDecl(Expr *E) { 5148 switch (E->getStmtClass()) { 5149 case Stmt::DeclRefExprClass: 5150 return cast<DeclRefExpr>(E)->getDecl(); 5151 case Stmt::MemberExprClass: 5152 // If this is an arrow operator, the address is an offset from 5153 // the base's value, so the object the base refers to is 5154 // irrelevant. 5155 if (cast<MemberExpr>(E)->isArrow()) 5156 return 0; 5157 // Otherwise, the expression refers to a part of the base 5158 return getPrimaryDecl(cast<MemberExpr>(E)->getBase()); 5159 case Stmt::ArraySubscriptExprClass: { 5160 // FIXME: This code shouldn't be necessary! We should catch the implicit 5161 // promotion of register arrays earlier. 5162 Expr* Base = cast<ArraySubscriptExpr>(E)->getBase(); 5163 if (ImplicitCastExpr* ICE = dyn_cast<ImplicitCastExpr>(Base)) { 5164 if (ICE->getSubExpr()->getType()->isArrayType()) 5165 return getPrimaryDecl(ICE->getSubExpr()); 5166 } 5167 return 0; 5168 } 5169 case Stmt::UnaryOperatorClass: { 5170 UnaryOperator *UO = cast<UnaryOperator>(E); 5171 5172 switch(UO->getOpcode()) { 5173 case UnaryOperator::Real: 5174 case UnaryOperator::Imag: 5175 case UnaryOperator::Extension: 5176 return getPrimaryDecl(UO->getSubExpr()); 5177 default: 5178 return 0; 5179 } 5180 } 5181 case Stmt::ParenExprClass: 5182 return getPrimaryDecl(cast<ParenExpr>(E)->getSubExpr()); 5183 case Stmt::ImplicitCastExprClass: 5184 // If the result of an implicit cast is an l-value, we care about 5185 // the sub-expression; otherwise, the result here doesn't matter. 5186 return getPrimaryDecl(cast<ImplicitCastExpr>(E)->getSubExpr()); 5187 default: 5188 return 0; 5189 } 5190} 5191 5192/// CheckAddressOfOperand - The operand of & must be either a function 5193/// designator or an lvalue designating an object. If it is an lvalue, the 5194/// object cannot be declared with storage class register or be a bit field. 5195/// Note: The usual conversions are *not* applied to the operand of the & 5196/// operator (C99 6.3.2.1p[2-4]), and its result is never an lvalue. 5197/// In C++, the operand might be an overloaded function name, in which case 5198/// we allow the '&' but retain the overloaded-function type. 5199QualType Sema::CheckAddressOfOperand(Expr *op, SourceLocation OpLoc) { 5200 // Make sure to ignore parentheses in subsequent checks 5201 op = op->IgnoreParens(); 5202 5203 if (op->isTypeDependent()) 5204 return Context.DependentTy; 5205 5206 if (getLangOptions().C99) { 5207 // Implement C99-only parts of addressof rules. 5208 if (UnaryOperator* uOp = dyn_cast<UnaryOperator>(op)) { 5209 if (uOp->getOpcode() == UnaryOperator::Deref) 5210 // Per C99 6.5.3.2, the address of a deref always returns a valid result 5211 // (assuming the deref expression is valid). 5212 return uOp->getSubExpr()->getType(); 5213 } 5214 // Technically, there should be a check for array subscript 5215 // expressions here, but the result of one is always an lvalue anyway. 5216 } 5217 NamedDecl *dcl = getPrimaryDecl(op); 5218 Expr::isLvalueResult lval = op->isLvalue(Context); 5219 5220 if (lval != Expr::LV_Valid && lval != Expr::LV_IncompleteVoidType) { 5221 // C99 6.5.3.2p1 5222 // The operand must be either an l-value or a function designator 5223 if (!op->getType()->isFunctionType()) { 5224 // FIXME: emit more specific diag... 5225 Diag(OpLoc, diag::err_typecheck_invalid_lvalue_addrof) 5226 << op->getSourceRange(); 5227 return QualType(); 5228 } 5229 } else if (op->getBitField()) { // C99 6.5.3.2p1 5230 // The operand cannot be a bit-field 5231 Diag(OpLoc, diag::err_typecheck_address_of) 5232 << "bit-field" << op->getSourceRange(); 5233 return QualType(); 5234 } else if (isa<ExtVectorElementExpr>(op) || (isa<ArraySubscriptExpr>(op) && 5235 cast<ArraySubscriptExpr>(op)->getBase()->getType()->isVectorType())){ 5236 // The operand cannot be an element of a vector 5237 Diag(OpLoc, diag::err_typecheck_address_of) 5238 << "vector element" << op->getSourceRange(); 5239 return QualType(); 5240 } else if (isa<ObjCPropertyRefExpr>(op)) { 5241 // cannot take address of a property expression. 5242 Diag(OpLoc, diag::err_typecheck_address_of) 5243 << "property expression" << op->getSourceRange(); 5244 return QualType(); 5245 } else if (ConditionalOperator *CO = dyn_cast<ConditionalOperator>(op)) { 5246 // FIXME: Can LHS ever be null here? 5247 if (!CheckAddressOfOperand(CO->getTrueExpr(), OpLoc).isNull()) 5248 return CheckAddressOfOperand(CO->getFalseExpr(), OpLoc); 5249 } else if (isa<UnresolvedLookupExpr>(op)) { 5250 return Context.OverloadTy; 5251 } else if (dcl) { // C99 6.5.3.2p1 5252 // We have an lvalue with a decl. Make sure the decl is not declared 5253 // with the register storage-class specifier. 5254 if (const VarDecl *vd = dyn_cast<VarDecl>(dcl)) { 5255 if (vd->getStorageClass() == VarDecl::Register) { 5256 Diag(OpLoc, diag::err_typecheck_address_of) 5257 << "register variable" << op->getSourceRange(); 5258 return QualType(); 5259 } 5260 } else if (isa<FunctionTemplateDecl>(dcl)) { 5261 return Context.OverloadTy; 5262 } else if (FieldDecl *FD = dyn_cast<FieldDecl>(dcl)) { 5263 // Okay: we can take the address of a field. 5264 // Could be a pointer to member, though, if there is an explicit 5265 // scope qualifier for the class. 5266 if (isa<DeclRefExpr>(op) && cast<DeclRefExpr>(op)->getQualifier()) { 5267 DeclContext *Ctx = dcl->getDeclContext(); 5268 if (Ctx && Ctx->isRecord()) { 5269 if (FD->getType()->isReferenceType()) { 5270 Diag(OpLoc, 5271 diag::err_cannot_form_pointer_to_member_of_reference_type) 5272 << FD->getDeclName() << FD->getType(); 5273 return QualType(); 5274 } 5275 5276 return Context.getMemberPointerType(op->getType(), 5277 Context.getTypeDeclType(cast<RecordDecl>(Ctx)).getTypePtr()); 5278 } 5279 } 5280 } else if (CXXMethodDecl *MD = dyn_cast<CXXMethodDecl>(dcl)) { 5281 // Okay: we can take the address of a function. 5282 // As above. 5283 if (isa<DeclRefExpr>(op) && cast<DeclRefExpr>(op)->getQualifier() && 5284 MD->isInstance()) 5285 return Context.getMemberPointerType(op->getType(), 5286 Context.getTypeDeclType(MD->getParent()).getTypePtr()); 5287 } else if (!isa<FunctionDecl>(dcl)) 5288 assert(0 && "Unknown/unexpected decl type"); 5289 } 5290 5291 if (lval == Expr::LV_IncompleteVoidType) { 5292 // Taking the address of a void variable is technically illegal, but we 5293 // allow it in cases which are otherwise valid. 5294 // Example: "extern void x; void* y = &x;". 5295 Diag(OpLoc, diag::ext_typecheck_addrof_void) << op->getSourceRange(); 5296 } 5297 5298 // If the operand has type "type", the result has type "pointer to type". 5299 return Context.getPointerType(op->getType()); 5300} 5301 5302QualType Sema::CheckIndirectionOperand(Expr *Op, SourceLocation OpLoc) { 5303 if (Op->isTypeDependent()) 5304 return Context.DependentTy; 5305 5306 UsualUnaryConversions(Op); 5307 QualType Ty = Op->getType(); 5308 5309 // Note that per both C89 and C99, this is always legal, even if ptype is an 5310 // incomplete type or void. It would be possible to warn about dereferencing 5311 // a void pointer, but it's completely well-defined, and such a warning is 5312 // unlikely to catch any mistakes. 5313 if (const PointerType *PT = Ty->getAs<PointerType>()) 5314 return PT->getPointeeType(); 5315 5316 if (const ObjCObjectPointerType *OPT = Ty->getAs<ObjCObjectPointerType>()) 5317 return OPT->getPointeeType(); 5318 5319 Diag(OpLoc, diag::err_typecheck_indirection_requires_pointer) 5320 << Ty << Op->getSourceRange(); 5321 return QualType(); 5322} 5323 5324static inline BinaryOperator::Opcode ConvertTokenKindToBinaryOpcode( 5325 tok::TokenKind Kind) { 5326 BinaryOperator::Opcode Opc; 5327 switch (Kind) { 5328 default: assert(0 && "Unknown binop!"); 5329 case tok::periodstar: Opc = BinaryOperator::PtrMemD; break; 5330 case tok::arrowstar: Opc = BinaryOperator::PtrMemI; break; 5331 case tok::star: Opc = BinaryOperator::Mul; break; 5332 case tok::slash: Opc = BinaryOperator::Div; break; 5333 case tok::percent: Opc = BinaryOperator::Rem; break; 5334 case tok::plus: Opc = BinaryOperator::Add; break; 5335 case tok::minus: Opc = BinaryOperator::Sub; break; 5336 case tok::lessless: Opc = BinaryOperator::Shl; break; 5337 case tok::greatergreater: Opc = BinaryOperator::Shr; break; 5338 case tok::lessequal: Opc = BinaryOperator::LE; break; 5339 case tok::less: Opc = BinaryOperator::LT; break; 5340 case tok::greaterequal: Opc = BinaryOperator::GE; break; 5341 case tok::greater: Opc = BinaryOperator::GT; break; 5342 case tok::exclaimequal: Opc = BinaryOperator::NE; break; 5343 case tok::equalequal: Opc = BinaryOperator::EQ; break; 5344 case tok::amp: Opc = BinaryOperator::And; break; 5345 case tok::caret: Opc = BinaryOperator::Xor; break; 5346 case tok::pipe: Opc = BinaryOperator::Or; break; 5347 case tok::ampamp: Opc = BinaryOperator::LAnd; break; 5348 case tok::pipepipe: Opc = BinaryOperator::LOr; break; 5349 case tok::equal: Opc = BinaryOperator::Assign; break; 5350 case tok::starequal: Opc = BinaryOperator::MulAssign; break; 5351 case tok::slashequal: Opc = BinaryOperator::DivAssign; break; 5352 case tok::percentequal: Opc = BinaryOperator::RemAssign; break; 5353 case tok::plusequal: Opc = BinaryOperator::AddAssign; break; 5354 case tok::minusequal: Opc = BinaryOperator::SubAssign; break; 5355 case tok::lesslessequal: Opc = BinaryOperator::ShlAssign; break; 5356 case tok::greatergreaterequal: Opc = BinaryOperator::ShrAssign; break; 5357 case tok::ampequal: Opc = BinaryOperator::AndAssign; break; 5358 case tok::caretequal: Opc = BinaryOperator::XorAssign; break; 5359 case tok::pipeequal: Opc = BinaryOperator::OrAssign; break; 5360 case tok::comma: Opc = BinaryOperator::Comma; break; 5361 } 5362 return Opc; 5363} 5364 5365static inline UnaryOperator::Opcode ConvertTokenKindToUnaryOpcode( 5366 tok::TokenKind Kind) { 5367 UnaryOperator::Opcode Opc; 5368 switch (Kind) { 5369 default: assert(0 && "Unknown unary op!"); 5370 case tok::plusplus: Opc = UnaryOperator::PreInc; break; 5371 case tok::minusminus: Opc = UnaryOperator::PreDec; break; 5372 case tok::amp: Opc = UnaryOperator::AddrOf; break; 5373 case tok::star: Opc = UnaryOperator::Deref; break; 5374 case tok::plus: Opc = UnaryOperator::Plus; break; 5375 case tok::minus: Opc = UnaryOperator::Minus; break; 5376 case tok::tilde: Opc = UnaryOperator::Not; break; 5377 case tok::exclaim: Opc = UnaryOperator::LNot; break; 5378 case tok::kw___real: Opc = UnaryOperator::Real; break; 5379 case tok::kw___imag: Opc = UnaryOperator::Imag; break; 5380 case tok::kw___extension__: Opc = UnaryOperator::Extension; break; 5381 } 5382 return Opc; 5383} 5384 5385/// CreateBuiltinBinOp - Creates a new built-in binary operation with 5386/// operator @p Opc at location @c TokLoc. This routine only supports 5387/// built-in operations; ActOnBinOp handles overloaded operators. 5388Action::OwningExprResult Sema::CreateBuiltinBinOp(SourceLocation OpLoc, 5389 unsigned Op, 5390 Expr *lhs, Expr *rhs) { 5391 QualType ResultTy; // Result type of the binary operator. 5392 BinaryOperator::Opcode Opc = (BinaryOperator::Opcode)Op; 5393 // The following two variables are used for compound assignment operators 5394 QualType CompLHSTy; // Type of LHS after promotions for computation 5395 QualType CompResultTy; // Type of computation result 5396 5397 switch (Opc) { 5398 case BinaryOperator::Assign: 5399 ResultTy = CheckAssignmentOperands(lhs, rhs, OpLoc, QualType()); 5400 break; 5401 case BinaryOperator::PtrMemD: 5402 case BinaryOperator::PtrMemI: 5403 ResultTy = CheckPointerToMemberOperands(lhs, rhs, OpLoc, 5404 Opc == BinaryOperator::PtrMemI); 5405 break; 5406 case BinaryOperator::Mul: 5407 case BinaryOperator::Div: 5408 ResultTy = CheckMultiplyDivideOperands(lhs, rhs, OpLoc); 5409 break; 5410 case BinaryOperator::Rem: 5411 ResultTy = CheckRemainderOperands(lhs, rhs, OpLoc); 5412 break; 5413 case BinaryOperator::Add: 5414 ResultTy = CheckAdditionOperands(lhs, rhs, OpLoc); 5415 break; 5416 case BinaryOperator::Sub: 5417 ResultTy = CheckSubtractionOperands(lhs, rhs, OpLoc); 5418 break; 5419 case BinaryOperator::Shl: 5420 case BinaryOperator::Shr: 5421 ResultTy = CheckShiftOperands(lhs, rhs, OpLoc); 5422 break; 5423 case BinaryOperator::LE: 5424 case BinaryOperator::LT: 5425 case BinaryOperator::GE: 5426 case BinaryOperator::GT: 5427 ResultTy = CheckCompareOperands(lhs, rhs, OpLoc, Opc, true); 5428 break; 5429 case BinaryOperator::EQ: 5430 case BinaryOperator::NE: 5431 ResultTy = CheckCompareOperands(lhs, rhs, OpLoc, Opc, false); 5432 break; 5433 case BinaryOperator::And: 5434 case BinaryOperator::Xor: 5435 case BinaryOperator::Or: 5436 ResultTy = CheckBitwiseOperands(lhs, rhs, OpLoc); 5437 break; 5438 case BinaryOperator::LAnd: 5439 case BinaryOperator::LOr: 5440 ResultTy = CheckLogicalOperands(lhs, rhs, OpLoc); 5441 break; 5442 case BinaryOperator::MulAssign: 5443 case BinaryOperator::DivAssign: 5444 CompResultTy = CheckMultiplyDivideOperands(lhs, rhs, OpLoc, true); 5445 CompLHSTy = CompResultTy; 5446 if (!CompResultTy.isNull()) 5447 ResultTy = CheckAssignmentOperands(lhs, rhs, OpLoc, CompResultTy); 5448 break; 5449 case BinaryOperator::RemAssign: 5450 CompResultTy = CheckRemainderOperands(lhs, rhs, OpLoc, true); 5451 CompLHSTy = CompResultTy; 5452 if (!CompResultTy.isNull()) 5453 ResultTy = CheckAssignmentOperands(lhs, rhs, OpLoc, CompResultTy); 5454 break; 5455 case BinaryOperator::AddAssign: 5456 CompResultTy = CheckAdditionOperands(lhs, rhs, OpLoc, &CompLHSTy); 5457 if (!CompResultTy.isNull()) 5458 ResultTy = CheckAssignmentOperands(lhs, rhs, OpLoc, CompResultTy); 5459 break; 5460 case BinaryOperator::SubAssign: 5461 CompResultTy = CheckSubtractionOperands(lhs, rhs, OpLoc, &CompLHSTy); 5462 if (!CompResultTy.isNull()) 5463 ResultTy = CheckAssignmentOperands(lhs, rhs, OpLoc, CompResultTy); 5464 break; 5465 case BinaryOperator::ShlAssign: 5466 case BinaryOperator::ShrAssign: 5467 CompResultTy = CheckShiftOperands(lhs, rhs, OpLoc, true); 5468 CompLHSTy = CompResultTy; 5469 if (!CompResultTy.isNull()) 5470 ResultTy = CheckAssignmentOperands(lhs, rhs, OpLoc, CompResultTy); 5471 break; 5472 case BinaryOperator::AndAssign: 5473 case BinaryOperator::XorAssign: 5474 case BinaryOperator::OrAssign: 5475 CompResultTy = CheckBitwiseOperands(lhs, rhs, OpLoc, true); 5476 CompLHSTy = CompResultTy; 5477 if (!CompResultTy.isNull()) 5478 ResultTy = CheckAssignmentOperands(lhs, rhs, OpLoc, CompResultTy); 5479 break; 5480 case BinaryOperator::Comma: 5481 ResultTy = CheckCommaOperands(lhs, rhs, OpLoc); 5482 break; 5483 } 5484 if (ResultTy.isNull()) 5485 return ExprError(); 5486 if (CompResultTy.isNull()) 5487 return Owned(new (Context) BinaryOperator(lhs, rhs, Opc, ResultTy, OpLoc)); 5488 else 5489 return Owned(new (Context) CompoundAssignOperator(lhs, rhs, Opc, ResultTy, 5490 CompLHSTy, CompResultTy, 5491 OpLoc)); 5492} 5493 5494/// SuggestParentheses - Emit a diagnostic together with a fixit hint that wraps 5495/// ParenRange in parentheses. 5496static void SuggestParentheses(Sema &Self, SourceLocation Loc, 5497 const PartialDiagnostic &PD, 5498 SourceRange ParenRange) 5499{ 5500 SourceLocation EndLoc = Self.PP.getLocForEndOfToken(ParenRange.getEnd()); 5501 if (!ParenRange.getEnd().isFileID() || EndLoc.isInvalid()) { 5502 // We can't display the parentheses, so just dig the 5503 // warning/error and return. 5504 Self.Diag(Loc, PD); 5505 return; 5506 } 5507 5508 Self.Diag(Loc, PD) 5509 << CodeModificationHint::CreateInsertion(ParenRange.getBegin(), "(") 5510 << CodeModificationHint::CreateInsertion(EndLoc, ")"); 5511} 5512 5513/// DiagnoseBitwisePrecedence - Emit a warning when bitwise and comparison 5514/// operators are mixed in a way that suggests that the programmer forgot that 5515/// comparison operators have higher precedence. The most typical example of 5516/// such code is "flags & 0x0020 != 0", which is equivalent to "flags & 1". 5517static void DiagnoseBitwisePrecedence(Sema &Self, BinaryOperator::Opcode Opc, 5518 SourceLocation OpLoc,Expr *lhs,Expr *rhs){ 5519 typedef BinaryOperator BinOp; 5520 BinOp::Opcode lhsopc = static_cast<BinOp::Opcode>(-1), 5521 rhsopc = static_cast<BinOp::Opcode>(-1); 5522 if (BinOp *BO = dyn_cast<BinOp>(lhs)) 5523 lhsopc = BO->getOpcode(); 5524 if (BinOp *BO = dyn_cast<BinOp>(rhs)) 5525 rhsopc = BO->getOpcode(); 5526 5527 // Subs are not binary operators. 5528 if (lhsopc == -1 && rhsopc == -1) 5529 return; 5530 5531 // Bitwise operations are sometimes used as eager logical ops. 5532 // Don't diagnose this. 5533 if ((BinOp::isComparisonOp(lhsopc) || BinOp::isBitwiseOp(lhsopc)) && 5534 (BinOp::isComparisonOp(rhsopc) || BinOp::isBitwiseOp(rhsopc))) 5535 return; 5536 5537 if (BinOp::isComparisonOp(lhsopc)) 5538 SuggestParentheses(Self, OpLoc, 5539 PDiag(diag::warn_precedence_bitwise_rel) 5540 << SourceRange(lhs->getLocStart(), OpLoc) 5541 << BinOp::getOpcodeStr(Opc) << BinOp::getOpcodeStr(lhsopc), 5542 SourceRange(cast<BinOp>(lhs)->getRHS()->getLocStart(), rhs->getLocEnd())); 5543 else if (BinOp::isComparisonOp(rhsopc)) 5544 SuggestParentheses(Self, OpLoc, 5545 PDiag(diag::warn_precedence_bitwise_rel) 5546 << SourceRange(OpLoc, rhs->getLocEnd()) 5547 << BinOp::getOpcodeStr(Opc) << BinOp::getOpcodeStr(rhsopc), 5548 SourceRange(lhs->getLocEnd(), cast<BinOp>(rhs)->getLHS()->getLocStart())); 5549} 5550 5551/// DiagnoseBinOpPrecedence - Emit warnings for expressions with tricky 5552/// precedence. This currently diagnoses only "arg1 'bitwise' arg2 'eq' arg3". 5553/// But it could also warn about arg1 && arg2 || arg3, as GCC 4.3+ does. 5554static void DiagnoseBinOpPrecedence(Sema &Self, BinaryOperator::Opcode Opc, 5555 SourceLocation OpLoc, Expr *lhs, Expr *rhs){ 5556 if (BinaryOperator::isBitwiseOp(Opc)) 5557 DiagnoseBitwisePrecedence(Self, Opc, OpLoc, lhs, rhs); 5558} 5559 5560// Binary Operators. 'Tok' is the token for the operator. 5561Action::OwningExprResult Sema::ActOnBinOp(Scope *S, SourceLocation TokLoc, 5562 tok::TokenKind Kind, 5563 ExprArg LHS, ExprArg RHS) { 5564 BinaryOperator::Opcode Opc = ConvertTokenKindToBinaryOpcode(Kind); 5565 Expr *lhs = LHS.takeAs<Expr>(), *rhs = RHS.takeAs<Expr>(); 5566 5567 assert((lhs != 0) && "ActOnBinOp(): missing left expression"); 5568 assert((rhs != 0) && "ActOnBinOp(): missing right expression"); 5569 5570 // Emit warnings for tricky precedence issues, e.g. "bitfield & 0x4 == 0" 5571 DiagnoseBinOpPrecedence(*this, Opc, TokLoc, lhs, rhs); 5572 5573 return BuildBinOp(S, TokLoc, Opc, lhs, rhs); 5574} 5575 5576Action::OwningExprResult Sema::BuildBinOp(Scope *S, SourceLocation OpLoc, 5577 BinaryOperator::Opcode Opc, 5578 Expr *lhs, Expr *rhs) { 5579 if (getLangOptions().CPlusPlus && 5580 (lhs->getType()->isOverloadableType() || 5581 rhs->getType()->isOverloadableType())) { 5582 // Find all of the overloaded operators visible from this 5583 // point. We perform both an operator-name lookup from the local 5584 // scope and an argument-dependent lookup based on the types of 5585 // the arguments. 5586 FunctionSet Functions; 5587 OverloadedOperatorKind OverOp = BinaryOperator::getOverloadedOperator(Opc); 5588 if (OverOp != OO_None) { 5589 if (S) 5590 LookupOverloadedOperatorName(OverOp, S, lhs->getType(), rhs->getType(), 5591 Functions); 5592 Expr *Args[2] = { lhs, rhs }; 5593 DeclarationName OpName 5594 = Context.DeclarationNames.getCXXOperatorName(OverOp); 5595 ArgumentDependentLookup(OpName, /*Operator*/true, Args, 2, Functions); 5596 } 5597 5598 // Build the (potentially-overloaded, potentially-dependent) 5599 // binary operation. 5600 return CreateOverloadedBinOp(OpLoc, Opc, Functions, lhs, rhs); 5601 } 5602 5603 // Build a built-in binary operation. 5604 return CreateBuiltinBinOp(OpLoc, Opc, lhs, rhs); 5605} 5606 5607Action::OwningExprResult Sema::CreateBuiltinUnaryOp(SourceLocation OpLoc, 5608 unsigned OpcIn, 5609 ExprArg InputArg) { 5610 UnaryOperator::Opcode Opc = static_cast<UnaryOperator::Opcode>(OpcIn); 5611 5612 // FIXME: Input is modified below, but InputArg is not updated appropriately. 5613 Expr *Input = (Expr *)InputArg.get(); 5614 QualType resultType; 5615 switch (Opc) { 5616 case UnaryOperator::OffsetOf: 5617 assert(false && "Invalid unary operator"); 5618 break; 5619 5620 case UnaryOperator::PreInc: 5621 case UnaryOperator::PreDec: 5622 case UnaryOperator::PostInc: 5623 case UnaryOperator::PostDec: 5624 resultType = CheckIncrementDecrementOperand(Input, OpLoc, 5625 Opc == UnaryOperator::PreInc || 5626 Opc == UnaryOperator::PostInc); 5627 break; 5628 case UnaryOperator::AddrOf: 5629 resultType = CheckAddressOfOperand(Input, OpLoc); 5630 break; 5631 case UnaryOperator::Deref: 5632 DefaultFunctionArrayConversion(Input); 5633 resultType = CheckIndirectionOperand(Input, OpLoc); 5634 break; 5635 case UnaryOperator::Plus: 5636 case UnaryOperator::Minus: 5637 UsualUnaryConversions(Input); 5638 resultType = Input->getType(); 5639 if (resultType->isDependentType()) 5640 break; 5641 if (resultType->isArithmeticType()) // C99 6.5.3.3p1 5642 break; 5643 else if (getLangOptions().CPlusPlus && // C++ [expr.unary.op]p6-7 5644 resultType->isEnumeralType()) 5645 break; 5646 else if (getLangOptions().CPlusPlus && // C++ [expr.unary.op]p6 5647 Opc == UnaryOperator::Plus && 5648 resultType->isPointerType()) 5649 break; 5650 5651 return ExprError(Diag(OpLoc, diag::err_typecheck_unary_expr) 5652 << resultType << Input->getSourceRange()); 5653 case UnaryOperator::Not: // bitwise complement 5654 UsualUnaryConversions(Input); 5655 resultType = Input->getType(); 5656 if (resultType->isDependentType()) 5657 break; 5658 // C99 6.5.3.3p1. We allow complex int and float as a GCC extension. 5659 if (resultType->isComplexType() || resultType->isComplexIntegerType()) 5660 // C99 does not support '~' for complex conjugation. 5661 Diag(OpLoc, diag::ext_integer_complement_complex) 5662 << resultType << Input->getSourceRange(); 5663 else if (!resultType->isIntegerType()) 5664 return ExprError(Diag(OpLoc, diag::err_typecheck_unary_expr) 5665 << resultType << Input->getSourceRange()); 5666 break; 5667 case UnaryOperator::LNot: // logical negation 5668 // Unlike +/-/~, integer promotions aren't done here (C99 6.5.3.3p5). 5669 DefaultFunctionArrayConversion(Input); 5670 resultType = Input->getType(); 5671 if (resultType->isDependentType()) 5672 break; 5673 if (!resultType->isScalarType()) // C99 6.5.3.3p1 5674 return ExprError(Diag(OpLoc, diag::err_typecheck_unary_expr) 5675 << resultType << Input->getSourceRange()); 5676 // LNot always has type int. C99 6.5.3.3p5. 5677 // In C++, it's bool. C++ 5.3.1p8 5678 resultType = getLangOptions().CPlusPlus ? Context.BoolTy : Context.IntTy; 5679 break; 5680 case UnaryOperator::Real: 5681 case UnaryOperator::Imag: 5682 resultType = CheckRealImagOperand(Input, OpLoc, Opc == UnaryOperator::Real); 5683 break; 5684 case UnaryOperator::Extension: 5685 resultType = Input->getType(); 5686 break; 5687 } 5688 if (resultType.isNull()) 5689 return ExprError(); 5690 5691 InputArg.release(); 5692 return Owned(new (Context) UnaryOperator(Input, Opc, resultType, OpLoc)); 5693} 5694 5695Action::OwningExprResult Sema::BuildUnaryOp(Scope *S, SourceLocation OpLoc, 5696 UnaryOperator::Opcode Opc, 5697 ExprArg input) { 5698 Expr *Input = (Expr*)input.get(); 5699 if (getLangOptions().CPlusPlus && Input->getType()->isOverloadableType() && 5700 Opc != UnaryOperator::Extension) { 5701 // Find all of the overloaded operators visible from this 5702 // point. We perform both an operator-name lookup from the local 5703 // scope and an argument-dependent lookup based on the types of 5704 // the arguments. 5705 FunctionSet Functions; 5706 OverloadedOperatorKind OverOp = UnaryOperator::getOverloadedOperator(Opc); 5707 if (OverOp != OO_None) { 5708 if (S) 5709 LookupOverloadedOperatorName(OverOp, S, Input->getType(), QualType(), 5710 Functions); 5711 DeclarationName OpName 5712 = Context.DeclarationNames.getCXXOperatorName(OverOp); 5713 ArgumentDependentLookup(OpName, /*Operator*/true, &Input, 1, Functions); 5714 } 5715 5716 return CreateOverloadedUnaryOp(OpLoc, Opc, Functions, move(input)); 5717 } 5718 5719 return CreateBuiltinUnaryOp(OpLoc, Opc, move(input)); 5720} 5721 5722// Unary Operators. 'Tok' is the token for the operator. 5723Action::OwningExprResult Sema::ActOnUnaryOp(Scope *S, SourceLocation OpLoc, 5724 tok::TokenKind Op, ExprArg input) { 5725 return BuildUnaryOp(S, OpLoc, ConvertTokenKindToUnaryOpcode(Op), move(input)); 5726} 5727 5728/// ActOnAddrLabel - Parse the GNU address of label extension: "&&foo". 5729Sema::OwningExprResult Sema::ActOnAddrLabel(SourceLocation OpLoc, 5730 SourceLocation LabLoc, 5731 IdentifierInfo *LabelII) { 5732 // Look up the record for this label identifier. 5733 LabelStmt *&LabelDecl = getLabelMap()[LabelII]; 5734 5735 // If we haven't seen this label yet, create a forward reference. It 5736 // will be validated and/or cleaned up in ActOnFinishFunctionBody. 5737 if (LabelDecl == 0) 5738 LabelDecl = new (Context) LabelStmt(LabLoc, LabelII, 0); 5739 5740 // Create the AST node. The address of a label always has type 'void*'. 5741 return Owned(new (Context) AddrLabelExpr(OpLoc, LabLoc, LabelDecl, 5742 Context.getPointerType(Context.VoidTy))); 5743} 5744 5745Sema::OwningExprResult 5746Sema::ActOnStmtExpr(SourceLocation LPLoc, StmtArg substmt, 5747 SourceLocation RPLoc) { // "({..})" 5748 Stmt *SubStmt = static_cast<Stmt*>(substmt.get()); 5749 assert(SubStmt && isa<CompoundStmt>(SubStmt) && "Invalid action invocation!"); 5750 CompoundStmt *Compound = cast<CompoundStmt>(SubStmt); 5751 5752 bool isFileScope = getCurFunctionOrMethodDecl() == 0; 5753 if (isFileScope) 5754 return ExprError(Diag(LPLoc, diag::err_stmtexpr_file_scope)); 5755 5756 // FIXME: there are a variety of strange constraints to enforce here, for 5757 // example, it is not possible to goto into a stmt expression apparently. 5758 // More semantic analysis is needed. 5759 5760 // If there are sub stmts in the compound stmt, take the type of the last one 5761 // as the type of the stmtexpr. 5762 QualType Ty = Context.VoidTy; 5763 5764 if (!Compound->body_empty()) { 5765 Stmt *LastStmt = Compound->body_back(); 5766 // If LastStmt is a label, skip down through into the body. 5767 while (LabelStmt *Label = dyn_cast<LabelStmt>(LastStmt)) 5768 LastStmt = Label->getSubStmt(); 5769 5770 if (Expr *LastExpr = dyn_cast<Expr>(LastStmt)) 5771 Ty = LastExpr->getType(); 5772 } 5773 5774 // FIXME: Check that expression type is complete/non-abstract; statement 5775 // expressions are not lvalues. 5776 5777 substmt.release(); 5778 return Owned(new (Context) StmtExpr(Compound, Ty, LPLoc, RPLoc)); 5779} 5780 5781Sema::OwningExprResult Sema::ActOnBuiltinOffsetOf(Scope *S, 5782 SourceLocation BuiltinLoc, 5783 SourceLocation TypeLoc, 5784 TypeTy *argty, 5785 OffsetOfComponent *CompPtr, 5786 unsigned NumComponents, 5787 SourceLocation RPLoc) { 5788 // FIXME: This function leaks all expressions in the offset components on 5789 // error. 5790 // FIXME: Preserve type source info. 5791 QualType ArgTy = GetTypeFromParser(argty); 5792 assert(!ArgTy.isNull() && "Missing type argument!"); 5793 5794 bool Dependent = ArgTy->isDependentType(); 5795 5796 // We must have at least one component that refers to the type, and the first 5797 // one is known to be a field designator. Verify that the ArgTy represents 5798 // a struct/union/class. 5799 if (!Dependent && !ArgTy->isRecordType()) 5800 return ExprError(Diag(TypeLoc, diag::err_offsetof_record_type) << ArgTy); 5801 5802 // FIXME: Type must be complete per C99 7.17p3 because a declaring a variable 5803 // with an incomplete type would be illegal. 5804 5805 // Otherwise, create a null pointer as the base, and iteratively process 5806 // the offsetof designators. 5807 QualType ArgTyPtr = Context.getPointerType(ArgTy); 5808 Expr* Res = new (Context) ImplicitValueInitExpr(ArgTyPtr); 5809 Res = new (Context) UnaryOperator(Res, UnaryOperator::Deref, 5810 ArgTy, SourceLocation()); 5811 5812 // offsetof with non-identifier designators (e.g. "offsetof(x, a.b[c])") are a 5813 // GCC extension, diagnose them. 5814 // FIXME: This diagnostic isn't actually visible because the location is in 5815 // a system header! 5816 if (NumComponents != 1) 5817 Diag(BuiltinLoc, diag::ext_offsetof_extended_field_designator) 5818 << SourceRange(CompPtr[1].LocStart, CompPtr[NumComponents-1].LocEnd); 5819 5820 if (!Dependent) { 5821 bool DidWarnAboutNonPOD = false; 5822 5823 if (RequireCompleteType(TypeLoc, Res->getType(), 5824 diag::err_offsetof_incomplete_type)) 5825 return ExprError(); 5826 5827 // FIXME: Dependent case loses a lot of information here. And probably 5828 // leaks like a sieve. 5829 for (unsigned i = 0; i != NumComponents; ++i) { 5830 const OffsetOfComponent &OC = CompPtr[i]; 5831 if (OC.isBrackets) { 5832 // Offset of an array sub-field. TODO: Should we allow vector elements? 5833 const ArrayType *AT = Context.getAsArrayType(Res->getType()); 5834 if (!AT) { 5835 Res->Destroy(Context); 5836 return ExprError(Diag(OC.LocEnd, diag::err_offsetof_array_type) 5837 << Res->getType()); 5838 } 5839 5840 // FIXME: C++: Verify that operator[] isn't overloaded. 5841 5842 // Promote the array so it looks more like a normal array subscript 5843 // expression. 5844 DefaultFunctionArrayConversion(Res); 5845 5846 // C99 6.5.2.1p1 5847 Expr *Idx = static_cast<Expr*>(OC.U.E); 5848 // FIXME: Leaks Res 5849 if (!Idx->isTypeDependent() && !Idx->getType()->isIntegerType()) 5850 return ExprError(Diag(Idx->getLocStart(), 5851 diag::err_typecheck_subscript_not_integer) 5852 << Idx->getSourceRange()); 5853 5854 Res = new (Context) ArraySubscriptExpr(Res, Idx, AT->getElementType(), 5855 OC.LocEnd); 5856 continue; 5857 } 5858 5859 const RecordType *RC = Res->getType()->getAs<RecordType>(); 5860 if (!RC) { 5861 Res->Destroy(Context); 5862 return ExprError(Diag(OC.LocEnd, diag::err_offsetof_record_type) 5863 << Res->getType()); 5864 } 5865 5866 // Get the decl corresponding to this. 5867 RecordDecl *RD = RC->getDecl(); 5868 if (CXXRecordDecl *CRD = dyn_cast<CXXRecordDecl>(RD)) { 5869 if (!CRD->isPOD() && !DidWarnAboutNonPOD) { 5870 ExprError(Diag(BuiltinLoc, diag::warn_offsetof_non_pod_type) 5871 << SourceRange(CompPtr[0].LocStart, OC.LocEnd) 5872 << Res->getType()); 5873 DidWarnAboutNonPOD = true; 5874 } 5875 } 5876 5877 LookupResult R(*this, OC.U.IdentInfo, OC.LocStart, LookupMemberName); 5878 LookupQualifiedName(R, RD); 5879 5880 FieldDecl *MemberDecl 5881 = dyn_cast_or_null<FieldDecl>(R.getAsSingleDecl(Context)); 5882 // FIXME: Leaks Res 5883 if (!MemberDecl) 5884 return ExprError(Diag(BuiltinLoc, diag::err_no_member) 5885 << OC.U.IdentInfo << RD << SourceRange(OC.LocStart, OC.LocEnd)); 5886 5887 // FIXME: C++: Verify that MemberDecl isn't a static field. 5888 // FIXME: Verify that MemberDecl isn't a bitfield. 5889 if (cast<RecordDecl>(MemberDecl->getDeclContext())->isAnonymousStructOrUnion()) { 5890 Res = BuildAnonymousStructUnionMemberReference( 5891 OC.LocEnd, MemberDecl, Res, OC.LocEnd).takeAs<Expr>(); 5892 } else { 5893 // MemberDecl->getType() doesn't get the right qualifiers, but it 5894 // doesn't matter here. 5895 Res = new (Context) MemberExpr(Res, false, MemberDecl, OC.LocEnd, 5896 MemberDecl->getType().getNonReferenceType()); 5897 } 5898 } 5899 } 5900 5901 return Owned(new (Context) UnaryOperator(Res, UnaryOperator::OffsetOf, 5902 Context.getSizeType(), BuiltinLoc)); 5903} 5904 5905 5906Sema::OwningExprResult Sema::ActOnTypesCompatibleExpr(SourceLocation BuiltinLoc, 5907 TypeTy *arg1,TypeTy *arg2, 5908 SourceLocation RPLoc) { 5909 // FIXME: Preserve type source info. 5910 QualType argT1 = GetTypeFromParser(arg1); 5911 QualType argT2 = GetTypeFromParser(arg2); 5912 5913 assert((!argT1.isNull() && !argT2.isNull()) && "Missing type argument(s)"); 5914 5915 if (getLangOptions().CPlusPlus) { 5916 Diag(BuiltinLoc, diag::err_types_compatible_p_in_cplusplus) 5917 << SourceRange(BuiltinLoc, RPLoc); 5918 return ExprError(); 5919 } 5920 5921 return Owned(new (Context) TypesCompatibleExpr(Context.IntTy, BuiltinLoc, 5922 argT1, argT2, RPLoc)); 5923} 5924 5925Sema::OwningExprResult Sema::ActOnChooseExpr(SourceLocation BuiltinLoc, 5926 ExprArg cond, 5927 ExprArg expr1, ExprArg expr2, 5928 SourceLocation RPLoc) { 5929 Expr *CondExpr = static_cast<Expr*>(cond.get()); 5930 Expr *LHSExpr = static_cast<Expr*>(expr1.get()); 5931 Expr *RHSExpr = static_cast<Expr*>(expr2.get()); 5932 5933 assert((CondExpr && LHSExpr && RHSExpr) && "Missing type argument(s)"); 5934 5935 QualType resType; 5936 bool ValueDependent = false; 5937 if (CondExpr->isTypeDependent() || CondExpr->isValueDependent()) { 5938 resType = Context.DependentTy; 5939 ValueDependent = true; 5940 } else { 5941 // The conditional expression is required to be a constant expression. 5942 llvm::APSInt condEval(32); 5943 SourceLocation ExpLoc; 5944 if (!CondExpr->isIntegerConstantExpr(condEval, Context, &ExpLoc)) 5945 return ExprError(Diag(ExpLoc, 5946 diag::err_typecheck_choose_expr_requires_constant) 5947 << CondExpr->getSourceRange()); 5948 5949 // If the condition is > zero, then the AST type is the same as the LSHExpr. 5950 resType = condEval.getZExtValue() ? LHSExpr->getType() : RHSExpr->getType(); 5951 ValueDependent = condEval.getZExtValue() ? LHSExpr->isValueDependent() 5952 : RHSExpr->isValueDependent(); 5953 } 5954 5955 cond.release(); expr1.release(); expr2.release(); 5956 return Owned(new (Context) ChooseExpr(BuiltinLoc, CondExpr, LHSExpr, RHSExpr, 5957 resType, RPLoc, 5958 resType->isDependentType(), 5959 ValueDependent)); 5960} 5961 5962//===----------------------------------------------------------------------===// 5963// Clang Extensions. 5964//===----------------------------------------------------------------------===// 5965 5966/// ActOnBlockStart - This callback is invoked when a block literal is started. 5967void Sema::ActOnBlockStart(SourceLocation CaretLoc, Scope *BlockScope) { 5968 // Analyze block parameters. 5969 BlockSemaInfo *BSI = new BlockSemaInfo(); 5970 5971 // Add BSI to CurBlock. 5972 BSI->PrevBlockInfo = CurBlock; 5973 CurBlock = BSI; 5974 5975 BSI->ReturnType = QualType(); 5976 BSI->TheScope = BlockScope; 5977 BSI->hasBlockDeclRefExprs = false; 5978 BSI->hasPrototype = false; 5979 BSI->SavedFunctionNeedsScopeChecking = CurFunctionNeedsScopeChecking; 5980 CurFunctionNeedsScopeChecking = false; 5981 5982 BSI->TheDecl = BlockDecl::Create(Context, CurContext, CaretLoc); 5983 PushDeclContext(BlockScope, BSI->TheDecl); 5984} 5985 5986void Sema::ActOnBlockArguments(Declarator &ParamInfo, Scope *CurScope) { 5987 assert(ParamInfo.getIdentifier()==0 && "block-id should have no identifier!"); 5988 5989 if (ParamInfo.getNumTypeObjects() == 0 5990 || ParamInfo.getTypeObject(0).Kind != DeclaratorChunk::Function) { 5991 ProcessDeclAttributes(CurScope, CurBlock->TheDecl, ParamInfo); 5992 QualType T = GetTypeForDeclarator(ParamInfo, CurScope); 5993 5994 if (T->isArrayType()) { 5995 Diag(ParamInfo.getSourceRange().getBegin(), 5996 diag::err_block_returns_array); 5997 return; 5998 } 5999 6000 // The parameter list is optional, if there was none, assume (). 6001 if (!T->isFunctionType()) 6002 T = Context.getFunctionType(T, NULL, 0, 0, 0); 6003 6004 CurBlock->hasPrototype = true; 6005 CurBlock->isVariadic = false; 6006 // Check for a valid sentinel attribute on this block. 6007 if (CurBlock->TheDecl->getAttr<SentinelAttr>()) { 6008 Diag(ParamInfo.getAttributes()->getLoc(), 6009 diag::warn_attribute_sentinel_not_variadic) << 1; 6010 // FIXME: remove the attribute. 6011 } 6012 QualType RetTy = T.getTypePtr()->getAs<FunctionType>()->getResultType(); 6013 6014 // Do not allow returning a objc interface by-value. 6015 if (RetTy->isObjCInterfaceType()) { 6016 Diag(ParamInfo.getSourceRange().getBegin(), 6017 diag::err_object_cannot_be_passed_returned_by_value) << 0 << RetTy; 6018 return; 6019 } 6020 return; 6021 } 6022 6023 // Analyze arguments to block. 6024 assert(ParamInfo.getTypeObject(0).Kind == DeclaratorChunk::Function && 6025 "Not a function declarator!"); 6026 DeclaratorChunk::FunctionTypeInfo &FTI = ParamInfo.getTypeObject(0).Fun; 6027 6028 CurBlock->hasPrototype = FTI.hasPrototype; 6029 CurBlock->isVariadic = true; 6030 6031 // Check for C99 6.7.5.3p10 - foo(void) is a non-varargs function that takes 6032 // no arguments, not a function that takes a single void argument. 6033 if (FTI.hasPrototype && 6034 FTI.NumArgs == 1 && !FTI.isVariadic && FTI.ArgInfo[0].Ident == 0 && 6035 (!FTI.ArgInfo[0].Param.getAs<ParmVarDecl>()->getType().getCVRQualifiers()&& 6036 FTI.ArgInfo[0].Param.getAs<ParmVarDecl>()->getType()->isVoidType())) { 6037 // empty arg list, don't push any params. 6038 CurBlock->isVariadic = false; 6039 } else if (FTI.hasPrototype) { 6040 for (unsigned i = 0, e = FTI.NumArgs; i != e; ++i) 6041 CurBlock->Params.push_back(FTI.ArgInfo[i].Param.getAs<ParmVarDecl>()); 6042 CurBlock->isVariadic = FTI.isVariadic; 6043 } 6044 CurBlock->TheDecl->setParams(Context, CurBlock->Params.data(), 6045 CurBlock->Params.size()); 6046 CurBlock->TheDecl->setIsVariadic(CurBlock->isVariadic); 6047 ProcessDeclAttributes(CurScope, CurBlock->TheDecl, ParamInfo); 6048 for (BlockDecl::param_iterator AI = CurBlock->TheDecl->param_begin(), 6049 E = CurBlock->TheDecl->param_end(); AI != E; ++AI) 6050 // If this has an identifier, add it to the scope stack. 6051 if ((*AI)->getIdentifier()) 6052 PushOnScopeChains(*AI, CurBlock->TheScope); 6053 6054 // Check for a valid sentinel attribute on this block. 6055 if (!CurBlock->isVariadic && 6056 CurBlock->TheDecl->getAttr<SentinelAttr>()) { 6057 Diag(ParamInfo.getAttributes()->getLoc(), 6058 diag::warn_attribute_sentinel_not_variadic) << 1; 6059 // FIXME: remove the attribute. 6060 } 6061 6062 // Analyze the return type. 6063 QualType T = GetTypeForDeclarator(ParamInfo, CurScope); 6064 QualType RetTy = T->getAs<FunctionType>()->getResultType(); 6065 6066 // Do not allow returning a objc interface by-value. 6067 if (RetTy->isObjCInterfaceType()) { 6068 Diag(ParamInfo.getSourceRange().getBegin(), 6069 diag::err_object_cannot_be_passed_returned_by_value) << 0 << RetTy; 6070 } else if (!RetTy->isDependentType()) 6071 CurBlock->ReturnType = RetTy; 6072} 6073 6074/// ActOnBlockError - If there is an error parsing a block, this callback 6075/// is invoked to pop the information about the block from the action impl. 6076void Sema::ActOnBlockError(SourceLocation CaretLoc, Scope *CurScope) { 6077 // Ensure that CurBlock is deleted. 6078 llvm::OwningPtr<BlockSemaInfo> CC(CurBlock); 6079 6080 CurFunctionNeedsScopeChecking = CurBlock->SavedFunctionNeedsScopeChecking; 6081 6082 // Pop off CurBlock, handle nested blocks. 6083 PopDeclContext(); 6084 CurBlock = CurBlock->PrevBlockInfo; 6085 // FIXME: Delete the ParmVarDecl objects as well??? 6086} 6087 6088/// ActOnBlockStmtExpr - This is called when the body of a block statement 6089/// literal was successfully completed. ^(int x){...} 6090Sema::OwningExprResult Sema::ActOnBlockStmtExpr(SourceLocation CaretLoc, 6091 StmtArg body, Scope *CurScope) { 6092 // If blocks are disabled, emit an error. 6093 if (!LangOpts.Blocks) 6094 Diag(CaretLoc, diag::err_blocks_disable); 6095 6096 // Ensure that CurBlock is deleted. 6097 llvm::OwningPtr<BlockSemaInfo> BSI(CurBlock); 6098 6099 PopDeclContext(); 6100 6101 // Pop off CurBlock, handle nested blocks. 6102 CurBlock = CurBlock->PrevBlockInfo; 6103 6104 QualType RetTy = Context.VoidTy; 6105 if (!BSI->ReturnType.isNull()) 6106 RetTy = BSI->ReturnType; 6107 6108 llvm::SmallVector<QualType, 8> ArgTypes; 6109 for (unsigned i = 0, e = BSI->Params.size(); i != e; ++i) 6110 ArgTypes.push_back(BSI->Params[i]->getType()); 6111 6112 bool NoReturn = BSI->TheDecl->getAttr<NoReturnAttr>(); 6113 QualType BlockTy; 6114 if (!BSI->hasPrototype) 6115 BlockTy = Context.getFunctionType(RetTy, 0, 0, false, 0, false, false, 0, 0, 6116 NoReturn); 6117 else 6118 BlockTy = Context.getFunctionType(RetTy, ArgTypes.data(), ArgTypes.size(), 6119 BSI->isVariadic, 0, false, false, 0, 0, 6120 NoReturn); 6121 6122 // FIXME: Check that return/parameter types are complete/non-abstract 6123 DiagnoseUnusedParameters(BSI->Params.begin(), BSI->Params.end()); 6124 BlockTy = Context.getBlockPointerType(BlockTy); 6125 6126 // If needed, diagnose invalid gotos and switches in the block. 6127 if (CurFunctionNeedsScopeChecking) 6128 DiagnoseInvalidJumps(static_cast<CompoundStmt*>(body.get())); 6129 CurFunctionNeedsScopeChecking = BSI->SavedFunctionNeedsScopeChecking; 6130 6131 BSI->TheDecl->setBody(body.takeAs<CompoundStmt>()); 6132 CheckFallThroughForBlock(BlockTy, BSI->TheDecl->getBody()); 6133 return Owned(new (Context) BlockExpr(BSI->TheDecl, BlockTy, 6134 BSI->hasBlockDeclRefExprs)); 6135} 6136 6137Sema::OwningExprResult Sema::ActOnVAArg(SourceLocation BuiltinLoc, 6138 ExprArg expr, TypeTy *type, 6139 SourceLocation RPLoc) { 6140 QualType T = GetTypeFromParser(type); 6141 Expr *E = static_cast<Expr*>(expr.get()); 6142 Expr *OrigExpr = E; 6143 6144 InitBuiltinVaListType(); 6145 6146 // Get the va_list type 6147 QualType VaListType = Context.getBuiltinVaListType(); 6148 if (VaListType->isArrayType()) { 6149 // Deal with implicit array decay; for example, on x86-64, 6150 // va_list is an array, but it's supposed to decay to 6151 // a pointer for va_arg. 6152 VaListType = Context.getArrayDecayedType(VaListType); 6153 // Make sure the input expression also decays appropriately. 6154 UsualUnaryConversions(E); 6155 } else { 6156 // Otherwise, the va_list argument must be an l-value because 6157 // it is modified by va_arg. 6158 if (!E->isTypeDependent() && 6159 CheckForModifiableLvalue(E, BuiltinLoc, *this)) 6160 return ExprError(); 6161 } 6162 6163 if (!E->isTypeDependent() && 6164 !Context.hasSameType(VaListType, E->getType())) { 6165 return ExprError(Diag(E->getLocStart(), 6166 diag::err_first_argument_to_va_arg_not_of_type_va_list) 6167 << OrigExpr->getType() << E->getSourceRange()); 6168 } 6169 6170 // FIXME: Check that type is complete/non-abstract 6171 // FIXME: Warn if a non-POD type is passed in. 6172 6173 expr.release(); 6174 return Owned(new (Context) VAArgExpr(BuiltinLoc, E, T.getNonReferenceType(), 6175 RPLoc)); 6176} 6177 6178Sema::OwningExprResult Sema::ActOnGNUNullExpr(SourceLocation TokenLoc) { 6179 // The type of __null will be int or long, depending on the size of 6180 // pointers on the target. 6181 QualType Ty; 6182 if (Context.Target.getPointerWidth(0) == Context.Target.getIntWidth()) 6183 Ty = Context.IntTy; 6184 else 6185 Ty = Context.LongTy; 6186 6187 return Owned(new (Context) GNUNullExpr(Ty, TokenLoc)); 6188} 6189 6190static void 6191MakeObjCStringLiteralCodeModificationHint(Sema& SemaRef, 6192 QualType DstType, 6193 Expr *SrcExpr, 6194 CodeModificationHint &Hint) { 6195 if (!SemaRef.getLangOptions().ObjC1) 6196 return; 6197 6198 const ObjCObjectPointerType *PT = DstType->getAs<ObjCObjectPointerType>(); 6199 if (!PT) 6200 return; 6201 6202 // Check if the destination is of type 'id'. 6203 if (!PT->isObjCIdType()) { 6204 // Check if the destination is the 'NSString' interface. 6205 const ObjCInterfaceDecl *ID = PT->getInterfaceDecl(); 6206 if (!ID || !ID->getIdentifier()->isStr("NSString")) 6207 return; 6208 } 6209 6210 // Strip off any parens and casts. 6211 StringLiteral *SL = dyn_cast<StringLiteral>(SrcExpr->IgnoreParenCasts()); 6212 if (!SL || SL->isWide()) 6213 return; 6214 6215 Hint = CodeModificationHint::CreateInsertion(SL->getLocStart(), "@"); 6216} 6217 6218bool Sema::DiagnoseAssignmentResult(AssignConvertType ConvTy, 6219 SourceLocation Loc, 6220 QualType DstType, QualType SrcType, 6221 Expr *SrcExpr, const char *Flavor) { 6222 // Decode the result (notice that AST's are still created for extensions). 6223 bool isInvalid = false; 6224 unsigned DiagKind; 6225 CodeModificationHint Hint; 6226 6227 switch (ConvTy) { 6228 default: assert(0 && "Unknown conversion type"); 6229 case Compatible: return false; 6230 case PointerToInt: 6231 DiagKind = diag::ext_typecheck_convert_pointer_int; 6232 break; 6233 case IntToPointer: 6234 DiagKind = diag::ext_typecheck_convert_int_pointer; 6235 break; 6236 case IncompatiblePointer: 6237 MakeObjCStringLiteralCodeModificationHint(*this, DstType, SrcExpr, Hint); 6238 DiagKind = diag::ext_typecheck_convert_incompatible_pointer; 6239 break; 6240 case IncompatiblePointerSign: 6241 DiagKind = diag::ext_typecheck_convert_incompatible_pointer_sign; 6242 break; 6243 case FunctionVoidPointer: 6244 DiagKind = diag::ext_typecheck_convert_pointer_void_func; 6245 break; 6246 case CompatiblePointerDiscardsQualifiers: 6247 // If the qualifiers lost were because we were applying the 6248 // (deprecated) C++ conversion from a string literal to a char* 6249 // (or wchar_t*), then there was no error (C++ 4.2p2). FIXME: 6250 // Ideally, this check would be performed in 6251 // CheckPointerTypesForAssignment. However, that would require a 6252 // bit of refactoring (so that the second argument is an 6253 // expression, rather than a type), which should be done as part 6254 // of a larger effort to fix CheckPointerTypesForAssignment for 6255 // C++ semantics. 6256 if (getLangOptions().CPlusPlus && 6257 IsStringLiteralToNonConstPointerConversion(SrcExpr, DstType)) 6258 return false; 6259 DiagKind = diag::ext_typecheck_convert_discards_qualifiers; 6260 break; 6261 case IncompatibleNestedPointerQualifiers: 6262 DiagKind = diag::ext_nested_pointer_qualifier_mismatch; 6263 break; 6264 case IntToBlockPointer: 6265 DiagKind = diag::err_int_to_block_pointer; 6266 break; 6267 case IncompatibleBlockPointer: 6268 DiagKind = diag::err_typecheck_convert_incompatible_block_pointer; 6269 break; 6270 case IncompatibleObjCQualifiedId: 6271 // FIXME: Diagnose the problem in ObjCQualifiedIdTypesAreCompatible, since 6272 // it can give a more specific diagnostic. 6273 DiagKind = diag::warn_incompatible_qualified_id; 6274 break; 6275 case IncompatibleVectors: 6276 DiagKind = diag::warn_incompatible_vectors; 6277 break; 6278 case Incompatible: 6279 DiagKind = diag::err_typecheck_convert_incompatible; 6280 isInvalid = true; 6281 break; 6282 } 6283 6284 Diag(Loc, DiagKind) << DstType << SrcType << Flavor 6285 << SrcExpr->getSourceRange() << Hint; 6286 return isInvalid; 6287} 6288 6289bool Sema::VerifyIntegerConstantExpression(const Expr *E, llvm::APSInt *Result){ 6290 llvm::APSInt ICEResult; 6291 if (E->isIntegerConstantExpr(ICEResult, Context)) { 6292 if (Result) 6293 *Result = ICEResult; 6294 return false; 6295 } 6296 6297 Expr::EvalResult EvalResult; 6298 6299 if (!E->Evaluate(EvalResult, Context) || !EvalResult.Val.isInt() || 6300 EvalResult.HasSideEffects) { 6301 Diag(E->getExprLoc(), diag::err_expr_not_ice) << E->getSourceRange(); 6302 6303 if (EvalResult.Diag) { 6304 // We only show the note if it's not the usual "invalid subexpression" 6305 // or if it's actually in a subexpression. 6306 if (EvalResult.Diag != diag::note_invalid_subexpr_in_ice || 6307 E->IgnoreParens() != EvalResult.DiagExpr->IgnoreParens()) 6308 Diag(EvalResult.DiagLoc, EvalResult.Diag); 6309 } 6310 6311 return true; 6312 } 6313 6314 Diag(E->getExprLoc(), diag::ext_expr_not_ice) << 6315 E->getSourceRange(); 6316 6317 if (EvalResult.Diag && 6318 Diags.getDiagnosticLevel(diag::ext_expr_not_ice) != Diagnostic::Ignored) 6319 Diag(EvalResult.DiagLoc, EvalResult.Diag); 6320 6321 if (Result) 6322 *Result = EvalResult.Val.getInt(); 6323 return false; 6324} 6325 6326Sema::ExpressionEvaluationContext 6327Sema::PushExpressionEvaluationContext(ExpressionEvaluationContext NewContext) { 6328 // Introduce a new set of potentially referenced declarations to the stack. 6329 if (NewContext == PotentiallyPotentiallyEvaluated) 6330 PotentiallyReferencedDeclStack.push_back(PotentiallyReferencedDecls()); 6331 6332 std::swap(ExprEvalContext, NewContext); 6333 return NewContext; 6334} 6335 6336void 6337Sema::PopExpressionEvaluationContext(ExpressionEvaluationContext OldContext, 6338 ExpressionEvaluationContext NewContext) { 6339 ExprEvalContext = NewContext; 6340 6341 if (OldContext == PotentiallyPotentiallyEvaluated) { 6342 // Mark any remaining declarations in the current position of the stack 6343 // as "referenced". If they were not meant to be referenced, semantic 6344 // analysis would have eliminated them (e.g., in ActOnCXXTypeId). 6345 PotentiallyReferencedDecls RemainingDecls; 6346 RemainingDecls.swap(PotentiallyReferencedDeclStack.back()); 6347 PotentiallyReferencedDeclStack.pop_back(); 6348 6349 for (PotentiallyReferencedDecls::iterator I = RemainingDecls.begin(), 6350 IEnd = RemainingDecls.end(); 6351 I != IEnd; ++I) 6352 MarkDeclarationReferenced(I->first, I->second); 6353 } 6354} 6355 6356/// \brief Note that the given declaration was referenced in the source code. 6357/// 6358/// This routine should be invoke whenever a given declaration is referenced 6359/// in the source code, and where that reference occurred. If this declaration 6360/// reference means that the the declaration is used (C++ [basic.def.odr]p2, 6361/// C99 6.9p3), then the declaration will be marked as used. 6362/// 6363/// \param Loc the location where the declaration was referenced. 6364/// 6365/// \param D the declaration that has been referenced by the source code. 6366void Sema::MarkDeclarationReferenced(SourceLocation Loc, Decl *D) { 6367 assert(D && "No declaration?"); 6368 6369 if (D->isUsed()) 6370 return; 6371 6372 // Mark a parameter or variable declaration "used", regardless of whether we're in a 6373 // template or not. The reason for this is that unevaluated expressions 6374 // (e.g. (void)sizeof()) constitute a use for warning purposes (-Wunused-variables and 6375 // -Wunused-parameters) 6376 if (isa<ParmVarDecl>(D) || 6377 (isa<VarDecl>(D) && D->getDeclContext()->isFunctionOrMethod())) 6378 D->setUsed(true); 6379 6380 // Do not mark anything as "used" within a dependent context; wait for 6381 // an instantiation. 6382 if (CurContext->isDependentContext()) 6383 return; 6384 6385 switch (ExprEvalContext) { 6386 case Unevaluated: 6387 // We are in an expression that is not potentially evaluated; do nothing. 6388 return; 6389 6390 case PotentiallyEvaluated: 6391 // We are in a potentially-evaluated expression, so this declaration is 6392 // "used"; handle this below. 6393 break; 6394 6395 case PotentiallyPotentiallyEvaluated: 6396 // We are in an expression that may be potentially evaluated; queue this 6397 // declaration reference until we know whether the expression is 6398 // potentially evaluated. 6399 PotentiallyReferencedDeclStack.back().push_back(std::make_pair(Loc, D)); 6400 return; 6401 } 6402 6403 // Note that this declaration has been used. 6404 if (CXXConstructorDecl *Constructor = dyn_cast<CXXConstructorDecl>(D)) { 6405 unsigned TypeQuals; 6406 if (Constructor->isImplicit() && Constructor->isDefaultConstructor()) { 6407 if (!Constructor->isUsed()) 6408 DefineImplicitDefaultConstructor(Loc, Constructor); 6409 } else if (Constructor->isImplicit() && 6410 Constructor->isCopyConstructor(Context, TypeQuals)) { 6411 if (!Constructor->isUsed()) 6412 DefineImplicitCopyConstructor(Loc, Constructor, TypeQuals); 6413 } 6414 } else if (CXXDestructorDecl *Destructor = dyn_cast<CXXDestructorDecl>(D)) { 6415 if (Destructor->isImplicit() && !Destructor->isUsed()) 6416 DefineImplicitDestructor(Loc, Destructor); 6417 6418 } else if (CXXMethodDecl *MethodDecl = dyn_cast<CXXMethodDecl>(D)) { 6419 if (MethodDecl->isImplicit() && MethodDecl->isOverloadedOperator() && 6420 MethodDecl->getOverloadedOperator() == OO_Equal) { 6421 if (!MethodDecl->isUsed()) 6422 DefineImplicitOverloadedAssign(Loc, MethodDecl); 6423 } 6424 } 6425 if (FunctionDecl *Function = dyn_cast<FunctionDecl>(D)) { 6426 // Implicit instantiation of function templates and member functions of 6427 // class templates. 6428 if (!Function->getBody() && Function->isImplicitlyInstantiable()) { 6429 bool AlreadyInstantiated = false; 6430 if (FunctionTemplateSpecializationInfo *SpecInfo 6431 = Function->getTemplateSpecializationInfo()) { 6432 if (SpecInfo->getPointOfInstantiation().isInvalid()) 6433 SpecInfo->setPointOfInstantiation(Loc); 6434 else if (SpecInfo->getTemplateSpecializationKind() 6435 == TSK_ImplicitInstantiation) 6436 AlreadyInstantiated = true; 6437 } else if (MemberSpecializationInfo *MSInfo 6438 = Function->getMemberSpecializationInfo()) { 6439 if (MSInfo->getPointOfInstantiation().isInvalid()) 6440 MSInfo->setPointOfInstantiation(Loc); 6441 else if (MSInfo->getTemplateSpecializationKind() 6442 == TSK_ImplicitInstantiation) 6443 AlreadyInstantiated = true; 6444 } 6445 6446 if (!AlreadyInstantiated) 6447 PendingImplicitInstantiations.push_back(std::make_pair(Function, Loc)); 6448 } 6449 6450 // FIXME: keep track of references to static functions 6451 Function->setUsed(true); 6452 return; 6453 } 6454 6455 if (VarDecl *Var = dyn_cast<VarDecl>(D)) { 6456 // Implicit instantiation of static data members of class templates. 6457 if (Var->isStaticDataMember() && 6458 Var->getInstantiatedFromStaticDataMember()) { 6459 MemberSpecializationInfo *MSInfo = Var->getMemberSpecializationInfo(); 6460 assert(MSInfo && "Missing member specialization information?"); 6461 if (MSInfo->getPointOfInstantiation().isInvalid() && 6462 MSInfo->getTemplateSpecializationKind()== TSK_ImplicitInstantiation) { 6463 MSInfo->setPointOfInstantiation(Loc); 6464 PendingImplicitInstantiations.push_back(std::make_pair(Var, Loc)); 6465 } 6466 } 6467 6468 // FIXME: keep track of references to static data? 6469 6470 D->setUsed(true); 6471 return; 6472 } 6473} 6474 6475bool Sema::CheckCallReturnType(QualType ReturnType, SourceLocation Loc, 6476 CallExpr *CE, FunctionDecl *FD) { 6477 if (ReturnType->isVoidType() || !ReturnType->isIncompleteType()) 6478 return false; 6479 6480 PartialDiagnostic Note = 6481 FD ? PDiag(diag::note_function_with_incomplete_return_type_declared_here) 6482 << FD->getDeclName() : PDiag(); 6483 SourceLocation NoteLoc = FD ? FD->getLocation() : SourceLocation(); 6484 6485 if (RequireCompleteType(Loc, ReturnType, 6486 FD ? 6487 PDiag(diag::err_call_function_incomplete_return) 6488 << CE->getSourceRange() << FD->getDeclName() : 6489 PDiag(diag::err_call_incomplete_return) 6490 << CE->getSourceRange(), 6491 std::make_pair(NoteLoc, Note))) 6492 return true; 6493 6494 return false; 6495} 6496 6497// Diagnose the common s/=/==/ typo. Note that adding parentheses 6498// will prevent this condition from triggering, which is what we want. 6499void Sema::DiagnoseAssignmentAsCondition(Expr *E) { 6500 SourceLocation Loc; 6501 6502 unsigned diagnostic = diag::warn_condition_is_assignment; 6503 6504 if (isa<BinaryOperator>(E)) { 6505 BinaryOperator *Op = cast<BinaryOperator>(E); 6506 if (Op->getOpcode() != BinaryOperator::Assign) 6507 return; 6508 6509 // Greylist some idioms by putting them into a warning subcategory. 6510 if (ObjCMessageExpr *ME 6511 = dyn_cast<ObjCMessageExpr>(Op->getRHS()->IgnoreParenCasts())) { 6512 Selector Sel = ME->getSelector(); 6513 6514 // self = [<foo> init...] 6515 if (isSelfExpr(Op->getLHS()) 6516 && Sel.getIdentifierInfoForSlot(0)->getName().startswith("init")) 6517 diagnostic = diag::warn_condition_is_idiomatic_assignment; 6518 6519 // <foo> = [<bar> nextObject] 6520 else if (Sel.isUnarySelector() && 6521 Sel.getIdentifierInfoForSlot(0)->getName() == "nextObject") 6522 diagnostic = diag::warn_condition_is_idiomatic_assignment; 6523 } 6524 6525 Loc = Op->getOperatorLoc(); 6526 } else if (isa<CXXOperatorCallExpr>(E)) { 6527 CXXOperatorCallExpr *Op = cast<CXXOperatorCallExpr>(E); 6528 if (Op->getOperator() != OO_Equal) 6529 return; 6530 6531 Loc = Op->getOperatorLoc(); 6532 } else { 6533 // Not an assignment. 6534 return; 6535 } 6536 6537 SourceLocation Open = E->getSourceRange().getBegin(); 6538 SourceLocation Close = PP.getLocForEndOfToken(E->getSourceRange().getEnd()); 6539 6540 Diag(Loc, diagnostic) 6541 << E->getSourceRange() 6542 << CodeModificationHint::CreateInsertion(Open, "(") 6543 << CodeModificationHint::CreateInsertion(Close, ")"); 6544} 6545 6546bool Sema::CheckBooleanCondition(Expr *&E, SourceLocation Loc) { 6547 DiagnoseAssignmentAsCondition(E); 6548 6549 if (!E->isTypeDependent()) { 6550 DefaultFunctionArrayConversion(E); 6551 6552 QualType T = E->getType(); 6553 6554 if (getLangOptions().CPlusPlus) { 6555 if (CheckCXXBooleanCondition(E)) // C++ 6.4p4 6556 return true; 6557 } else if (!T->isScalarType()) { // C99 6.8.4.1p1 6558 Diag(Loc, diag::err_typecheck_statement_requires_scalar) 6559 << T << E->getSourceRange(); 6560 return true; 6561 } 6562 } 6563 6564 return false; 6565} 6566