SemaExpr.cpp revision 8421ec07de0c295f54d1070b470a32155b8e0192
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 "clang/Sema/SemaInternal.h" 15#include "clang/Sema/Initialization.h" 16#include "clang/Sema/Lookup.h" 17#include "clang/Sema/AnalysisBasedWarnings.h" 18#include "clang/AST/ASTContext.h" 19#include "clang/AST/CXXInheritance.h" 20#include "clang/AST/DeclObjC.h" 21#include "clang/AST/DeclTemplate.h" 22#include "clang/AST/EvaluatedExprVisitor.h" 23#include "clang/AST/Expr.h" 24#include "clang/AST/ExprCXX.h" 25#include "clang/AST/ExprObjC.h" 26#include "clang/AST/RecursiveASTVisitor.h" 27#include "clang/AST/TypeLoc.h" 28#include "clang/Basic/PartialDiagnostic.h" 29#include "clang/Basic/SourceManager.h" 30#include "clang/Basic/TargetInfo.h" 31#include "clang/Lex/LiteralSupport.h" 32#include "clang/Lex/Preprocessor.h" 33#include "clang/Sema/DeclSpec.h" 34#include "clang/Sema/Designator.h" 35#include "clang/Sema/Scope.h" 36#include "clang/Sema/ScopeInfo.h" 37#include "clang/Sema/ParsedTemplate.h" 38#include "clang/Sema/Template.h" 39using namespace clang; 40using namespace sema; 41 42 43/// \brief Determine whether the use of this declaration is valid, and 44/// emit any corresponding diagnostics. 45/// 46/// This routine diagnoses various problems with referencing 47/// declarations that can occur when using a declaration. For example, 48/// it might warn if a deprecated or unavailable declaration is being 49/// used, or produce an error (and return true) if a C++0x deleted 50/// function is being used. 51/// 52/// If IgnoreDeprecated is set to true, this should not want about deprecated 53/// decls. 54/// 55/// \returns true if there was an error (this declaration cannot be 56/// referenced), false otherwise. 57/// 58bool Sema::DiagnoseUseOfDecl(NamedDecl *D, SourceLocation Loc) { 59 // See if the decl is deprecated. 60 if (D->getAttr<DeprecatedAttr>()) { 61 EmitDeprecationWarning(D, Loc); 62 } 63 64 // See if the decl is unavailable 65 if (D->getAttr<UnavailableAttr>()) { 66 Diag(Loc, diag::err_unavailable) << D->getDeclName(); 67 Diag(D->getLocation(), diag::note_unavailable_here) << 0; 68 } 69 70 // See if this is a deleted function. 71 if (FunctionDecl *FD = dyn_cast<FunctionDecl>(D)) { 72 if (FD->isDeleted()) { 73 Diag(Loc, diag::err_deleted_function_use); 74 Diag(D->getLocation(), diag::note_unavailable_here) << true; 75 return true; 76 } 77 } 78 79 return false; 80} 81 82/// DiagnoseSentinelCalls - This routine checks on method dispatch calls 83/// (and other functions in future), which have been declared with sentinel 84/// attribute. It warns if call does not have the sentinel argument. 85/// 86void Sema::DiagnoseSentinelCalls(NamedDecl *D, SourceLocation Loc, 87 Expr **Args, unsigned NumArgs) { 88 const SentinelAttr *attr = D->getAttr<SentinelAttr>(); 89 if (!attr) 90 return; 91 92 // FIXME: In C++0x, if any of the arguments are parameter pack 93 // expansions, we can't check for the sentinel now. 94 int sentinelPos = attr->getSentinel(); 95 int nullPos = attr->getNullPos(); 96 97 // FIXME. ObjCMethodDecl and FunctionDecl need be derived from the same common 98 // base class. Then we won't be needing two versions of the same code. 99 unsigned int i = 0; 100 bool warnNotEnoughArgs = false; 101 int isMethod = 0; 102 if (ObjCMethodDecl *MD = dyn_cast<ObjCMethodDecl>(D)) { 103 // skip over named parameters. 104 ObjCMethodDecl::param_iterator P, E = MD->param_end(); 105 for (P = MD->param_begin(); (P != E && i < NumArgs); ++P) { 106 if (nullPos) 107 --nullPos; 108 else 109 ++i; 110 } 111 warnNotEnoughArgs = (P != E || i >= NumArgs); 112 isMethod = 1; 113 } else if (FunctionDecl *FD = dyn_cast<FunctionDecl>(D)) { 114 // skip over named parameters. 115 ObjCMethodDecl::param_iterator P, E = FD->param_end(); 116 for (P = FD->param_begin(); (P != E && i < NumArgs); ++P) { 117 if (nullPos) 118 --nullPos; 119 else 120 ++i; 121 } 122 warnNotEnoughArgs = (P != E || i >= NumArgs); 123 } else if (VarDecl *V = dyn_cast<VarDecl>(D)) { 124 // block or function pointer call. 125 QualType Ty = V->getType(); 126 if (Ty->isBlockPointerType() || Ty->isFunctionPointerType()) { 127 const FunctionType *FT = Ty->isFunctionPointerType() 128 ? Ty->getAs<PointerType>()->getPointeeType()->getAs<FunctionType>() 129 : Ty->getAs<BlockPointerType>()->getPointeeType()->getAs<FunctionType>(); 130 if (const FunctionProtoType *Proto = dyn_cast<FunctionProtoType>(FT)) { 131 unsigned NumArgsInProto = Proto->getNumArgs(); 132 unsigned k; 133 for (k = 0; (k != NumArgsInProto && i < NumArgs); k++) { 134 if (nullPos) 135 --nullPos; 136 else 137 ++i; 138 } 139 warnNotEnoughArgs = (k != NumArgsInProto || i >= NumArgs); 140 } 141 if (Ty->isBlockPointerType()) 142 isMethod = 2; 143 } else 144 return; 145 } else 146 return; 147 148 if (warnNotEnoughArgs) { 149 Diag(Loc, diag::warn_not_enough_argument) << D->getDeclName(); 150 Diag(D->getLocation(), diag::note_sentinel_here) << isMethod; 151 return; 152 } 153 int sentinel = i; 154 while (sentinelPos > 0 && i < NumArgs-1) { 155 --sentinelPos; 156 ++i; 157 } 158 if (sentinelPos > 0) { 159 Diag(Loc, diag::warn_not_enough_argument) << D->getDeclName(); 160 Diag(D->getLocation(), diag::note_sentinel_here) << isMethod; 161 return; 162 } 163 while (i < NumArgs-1) { 164 ++i; 165 ++sentinel; 166 } 167 Expr *sentinelExpr = Args[sentinel]; 168 if (!sentinelExpr) return; 169 if (sentinelExpr->isTypeDependent()) return; 170 if (sentinelExpr->isValueDependent()) return; 171 if (sentinelExpr->getType()->isAnyPointerType() && 172 sentinelExpr->IgnoreParenCasts()->isNullPointerConstant(Context, 173 Expr::NPC_ValueDependentIsNull)) 174 return; 175 176 // Unfortunately, __null has type 'int'. 177 if (isa<GNUNullExpr>(sentinelExpr)) return; 178 179 Diag(Loc, diag::warn_missing_sentinel) << isMethod; 180 Diag(D->getLocation(), diag::note_sentinel_here) << isMethod; 181} 182 183SourceRange Sema::getExprRange(ExprTy *E) const { 184 Expr *Ex = (Expr *)E; 185 return Ex? Ex->getSourceRange() : SourceRange(); 186} 187 188//===----------------------------------------------------------------------===// 189// Standard Promotions and Conversions 190//===----------------------------------------------------------------------===// 191 192/// DefaultFunctionArrayConversion (C99 6.3.2.1p3, C99 6.3.2.1p4). 193void Sema::DefaultFunctionArrayConversion(Expr *&E) { 194 QualType Ty = E->getType(); 195 assert(!Ty.isNull() && "DefaultFunctionArrayConversion - missing type"); 196 197 if (Ty->isFunctionType()) 198 ImpCastExprToType(E, Context.getPointerType(Ty), 199 CK_FunctionToPointerDecay); 200 else if (Ty->isArrayType()) { 201 // In C90 mode, arrays only promote to pointers if the array expression is 202 // an lvalue. The relevant legalese is C90 6.2.2.1p3: "an lvalue that has 203 // type 'array of type' is converted to an expression that has type 'pointer 204 // to type'...". In C99 this was changed to: C99 6.3.2.1p3: "an expression 205 // that has type 'array of type' ...". The relevant change is "an lvalue" 206 // (C90) to "an expression" (C99). 207 // 208 // C++ 4.2p1: 209 // An lvalue or rvalue of type "array of N T" or "array of unknown bound of 210 // T" can be converted to an rvalue of type "pointer to T". 211 // 212 if (getLangOptions().C99 || getLangOptions().CPlusPlus || 213 E->isLvalue(Context) == Expr::LV_Valid) 214 ImpCastExprToType(E, Context.getArrayDecayedType(Ty), 215 CK_ArrayToPointerDecay); 216 } 217} 218 219void Sema::DefaultFunctionArrayLvalueConversion(Expr *&E) { 220 DefaultFunctionArrayConversion(E); 221 222 QualType Ty = E->getType(); 223 assert(!Ty.isNull() && "DefaultFunctionArrayLvalueConversion - missing type"); 224 if (!Ty->isDependentType() && Ty.hasQualifiers() && 225 (!getLangOptions().CPlusPlus || !Ty->isRecordType()) && 226 E->isLvalue(Context) == Expr::LV_Valid) { 227 // C++ [conv.lval]p1: 228 // [...] If T is a non-class type, the type of the rvalue is the 229 // cv-unqualified version of T. Otherwise, the type of the 230 // rvalue is T 231 // 232 // C99 6.3.2.1p2: 233 // If the lvalue has qualified type, the value has the unqualified 234 // version of the type of the lvalue; otherwise, the value has the 235 // type of the lvalue. 236 ImpCastExprToType(E, Ty.getUnqualifiedType(), CK_NoOp); 237 } 238} 239 240 241/// UsualUnaryConversions - Performs various conversions that are common to most 242/// operators (C99 6.3). The conversions of array and function types are 243/// sometimes surpressed. For example, the array->pointer conversion doesn't 244/// apply if the array is an argument to the sizeof or address (&) operators. 245/// In these instances, this routine should *not* be called. 246Expr *Sema::UsualUnaryConversions(Expr *&Expr) { 247 QualType Ty = Expr->getType(); 248 assert(!Ty.isNull() && "UsualUnaryConversions - missing type"); 249 250 // C99 6.3.1.1p2: 251 // 252 // The following may be used in an expression wherever an int or 253 // unsigned int may be used: 254 // - an object or expression with an integer type whose integer 255 // conversion rank is less than or equal to the rank of int 256 // and unsigned int. 257 // - A bit-field of type _Bool, int, signed int, or unsigned int. 258 // 259 // If an int can represent all values of the original type, the 260 // value is converted to an int; otherwise, it is converted to an 261 // unsigned int. These are called the integer promotions. All 262 // other types are unchanged by the integer promotions. 263 QualType PTy = Context.isPromotableBitField(Expr); 264 if (!PTy.isNull()) { 265 ImpCastExprToType(Expr, PTy, CK_IntegralCast); 266 return Expr; 267 } 268 if (Ty->isPromotableIntegerType()) { 269 QualType PT = Context.getPromotedIntegerType(Ty); 270 ImpCastExprToType(Expr, PT, CK_IntegralCast); 271 return Expr; 272 } 273 274 DefaultFunctionArrayLvalueConversion(Expr); 275 return Expr; 276} 277 278/// DefaultArgumentPromotion (C99 6.5.2.2p6). Used for function calls that 279/// do not have a prototype. Arguments that have type float are promoted to 280/// double. All other argument types are converted by UsualUnaryConversions(). 281void Sema::DefaultArgumentPromotion(Expr *&Expr) { 282 QualType Ty = Expr->getType(); 283 assert(!Ty.isNull() && "DefaultArgumentPromotion - missing type"); 284 285 // If this is a 'float' (CVR qualified or typedef) promote to double. 286 if (Ty->isSpecificBuiltinType(BuiltinType::Float)) 287 return ImpCastExprToType(Expr, Context.DoubleTy, 288 CK_FloatingCast); 289 290 UsualUnaryConversions(Expr); 291} 292 293/// DefaultVariadicArgumentPromotion - Like DefaultArgumentPromotion, but 294/// will warn if the resulting type is not a POD type, and rejects ObjC 295/// interfaces passed by value. This returns true if the argument type is 296/// completely illegal. 297bool Sema::DefaultVariadicArgumentPromotion(Expr *&Expr, VariadicCallType CT, 298 FunctionDecl *FDecl) { 299 DefaultArgumentPromotion(Expr); 300 301 // __builtin_va_start takes the second argument as a "varargs" argument, but 302 // it doesn't actually do anything with it. It doesn't need to be non-pod 303 // etc. 304 if (FDecl && FDecl->getBuiltinID() == Builtin::BI__builtin_va_start) 305 return false; 306 307 if (Expr->getType()->isObjCObjectType() && 308 DiagRuntimeBehavior(Expr->getLocStart(), 309 PDiag(diag::err_cannot_pass_objc_interface_to_vararg) 310 << Expr->getType() << CT)) 311 return true; 312 313 if (!Expr->getType()->isPODType() && 314 DiagRuntimeBehavior(Expr->getLocStart(), 315 PDiag(diag::warn_cannot_pass_non_pod_arg_to_vararg) 316 << Expr->getType() << CT)) 317 return true; 318 319 return false; 320} 321 322 323/// UsualArithmeticConversions - Performs various conversions that are common to 324/// binary operators (C99 6.3.1.8). If both operands aren't arithmetic, this 325/// routine returns the first non-arithmetic type found. The client is 326/// responsible for emitting appropriate error diagnostics. 327/// FIXME: verify the conversion rules for "complex int" are consistent with 328/// GCC. 329QualType Sema::UsualArithmeticConversions(Expr *&lhsExpr, Expr *&rhsExpr, 330 bool isCompAssign) { 331 if (!isCompAssign) 332 UsualUnaryConversions(lhsExpr); 333 334 UsualUnaryConversions(rhsExpr); 335 336 // For conversion purposes, we ignore any qualifiers. 337 // For example, "const float" and "float" are equivalent. 338 QualType lhs = 339 Context.getCanonicalType(lhsExpr->getType()).getUnqualifiedType(); 340 QualType rhs = 341 Context.getCanonicalType(rhsExpr->getType()).getUnqualifiedType(); 342 343 // If both types are identical, no conversion is needed. 344 if (lhs == rhs) 345 return lhs; 346 347 // If either side is a non-arithmetic type (e.g. a pointer), we are done. 348 // The caller can deal with this (e.g. pointer + int). 349 if (!lhs->isArithmeticType() || !rhs->isArithmeticType()) 350 return lhs; 351 352 // Perform bitfield promotions. 353 QualType LHSBitfieldPromoteTy = Context.isPromotableBitField(lhsExpr); 354 if (!LHSBitfieldPromoteTy.isNull()) 355 lhs = LHSBitfieldPromoteTy; 356 QualType RHSBitfieldPromoteTy = Context.isPromotableBitField(rhsExpr); 357 if (!RHSBitfieldPromoteTy.isNull()) 358 rhs = RHSBitfieldPromoteTy; 359 360 QualType destType = Context.UsualArithmeticConversionsType(lhs, rhs); 361 if (!isCompAssign) 362 ImpCastExprToType(lhsExpr, destType, CK_Unknown); 363 ImpCastExprToType(rhsExpr, destType, CK_Unknown); 364 return destType; 365} 366 367//===----------------------------------------------------------------------===// 368// Semantic Analysis for various Expression Types 369//===----------------------------------------------------------------------===// 370 371 372/// ActOnStringLiteral - The specified tokens were lexed as pasted string 373/// fragments (e.g. "foo" "bar" L"baz"). The result string has to handle string 374/// concatenation ([C99 5.1.1.2, translation phase #6]), so it may come from 375/// multiple tokens. However, the common case is that StringToks points to one 376/// string. 377/// 378ExprResult 379Sema::ActOnStringLiteral(const Token *StringToks, unsigned NumStringToks) { 380 assert(NumStringToks && "Must have at least one string!"); 381 382 StringLiteralParser Literal(StringToks, NumStringToks, PP); 383 if (Literal.hadError) 384 return ExprError(); 385 386 llvm::SmallVector<SourceLocation, 4> StringTokLocs; 387 for (unsigned i = 0; i != NumStringToks; ++i) 388 StringTokLocs.push_back(StringToks[i].getLocation()); 389 390 QualType StrTy = Context.CharTy; 391 if (Literal.AnyWide) StrTy = Context.getWCharType(); 392 if (Literal.Pascal) StrTy = Context.UnsignedCharTy; 393 394 // A C++ string literal has a const-qualified element type (C++ 2.13.4p1). 395 if (getLangOptions().CPlusPlus || getLangOptions().ConstStrings) 396 StrTy.addConst(); 397 398 // Get an array type for the string, according to C99 6.4.5. This includes 399 // the nul terminator character as well as the string length for pascal 400 // strings. 401 StrTy = Context.getConstantArrayType(StrTy, 402 llvm::APInt(32, Literal.GetNumStringChars()+1), 403 ArrayType::Normal, 0); 404 405 // Pass &StringTokLocs[0], StringTokLocs.size() to factory! 406 return Owned(StringLiteral::Create(Context, Literal.GetString(), 407 Literal.GetStringLength(), 408 Literal.AnyWide, StrTy, 409 &StringTokLocs[0], 410 StringTokLocs.size())); 411} 412 413/// ShouldSnapshotBlockValueReference - Return true if a reference inside of 414/// CurBlock to VD should cause it to be snapshotted (as we do for auto 415/// variables defined outside the block) or false if this is not needed (e.g. 416/// for values inside the block or for globals). 417/// 418/// This also keeps the 'hasBlockDeclRefExprs' in the BlockScopeInfo records 419/// up-to-date. 420/// 421static bool ShouldSnapshotBlockValueReference(Sema &S, BlockScopeInfo *CurBlock, 422 ValueDecl *VD) { 423 // If the value is defined inside the block, we couldn't snapshot it even if 424 // we wanted to. 425 if (CurBlock->TheDecl == VD->getDeclContext()) 426 return false; 427 428 // If this is an enum constant or function, it is constant, don't snapshot. 429 if (isa<EnumConstantDecl>(VD) || isa<FunctionDecl>(VD)) 430 return false; 431 432 // If this is a reference to an extern, static, or global variable, no need to 433 // snapshot it. 434 // FIXME: What about 'const' variables in C++? 435 if (const VarDecl *Var = dyn_cast<VarDecl>(VD)) 436 if (!Var->hasLocalStorage()) 437 return false; 438 439 // Blocks that have these can't be constant. 440 CurBlock->hasBlockDeclRefExprs = true; 441 442 // If we have nested blocks, the decl may be declared in an outer block (in 443 // which case that outer block doesn't get "hasBlockDeclRefExprs") or it may 444 // be defined outside all of the current blocks (in which case the blocks do 445 // all get the bit). Walk the nesting chain. 446 for (unsigned I = S.FunctionScopes.size() - 1; I; --I) { 447 BlockScopeInfo *NextBlock = dyn_cast<BlockScopeInfo>(S.FunctionScopes[I]); 448 449 if (!NextBlock) 450 continue; 451 452 // If we found the defining block for the variable, don't mark the block as 453 // having a reference outside it. 454 if (NextBlock->TheDecl == VD->getDeclContext()) 455 break; 456 457 // Otherwise, the DeclRef from the inner block causes the outer one to need 458 // a snapshot as well. 459 NextBlock->hasBlockDeclRefExprs = true; 460 } 461 462 return true; 463} 464 465 466ExprResult 467Sema::BuildDeclRefExpr(ValueDecl *D, QualType Ty, SourceLocation Loc, 468 const CXXScopeSpec *SS) { 469 DeclarationNameInfo NameInfo(D->getDeclName(), Loc); 470 return BuildDeclRefExpr(D, Ty, NameInfo, SS); 471} 472 473/// BuildDeclRefExpr - Build a DeclRefExpr. 474ExprResult 475Sema::BuildDeclRefExpr(ValueDecl *D, QualType Ty, 476 const DeclarationNameInfo &NameInfo, 477 const CXXScopeSpec *SS) { 478 if (Context.getCanonicalType(Ty) == Context.UndeducedAutoTy) { 479 Diag(NameInfo.getLoc(), 480 diag::err_auto_variable_cannot_appear_in_own_initializer) 481 << D->getDeclName(); 482 return ExprError(); 483 } 484 485 if (const VarDecl *VD = dyn_cast<VarDecl>(D)) { 486 if (isa<NonTypeTemplateParmDecl>(VD)) { 487 // Non-type template parameters can be referenced anywhere they are 488 // visible. 489 Ty = Ty.getNonLValueExprType(Context); 490 } else if (const CXXMethodDecl *MD = dyn_cast<CXXMethodDecl>(CurContext)) { 491 if (const FunctionDecl *FD = MD->getParent()->isLocalClass()) { 492 if (VD->hasLocalStorage() && VD->getDeclContext() != CurContext) { 493 Diag(NameInfo.getLoc(), 494 diag::err_reference_to_local_var_in_enclosing_function) 495 << D->getIdentifier() << FD->getDeclName(); 496 Diag(D->getLocation(), diag::note_local_variable_declared_here) 497 << D->getIdentifier(); 498 return ExprError(); 499 } 500 } 501 } 502 } 503 504 MarkDeclarationReferenced(NameInfo.getLoc(), D); 505 506 return Owned(DeclRefExpr::Create(Context, 507 SS? (NestedNameSpecifier *)SS->getScopeRep() : 0, 508 SS? SS->getRange() : SourceRange(), 509 D, NameInfo, Ty)); 510} 511 512/// \brief Given a field that represents a member of an anonymous 513/// struct/union, build the path from that field's context to the 514/// actual member. 515/// 516/// Construct the sequence of field member references we'll have to 517/// perform to get to the field in the anonymous union/struct. The 518/// list of members is built from the field outward, so traverse it 519/// backwards to go from an object in the current context to the field 520/// we found. 521/// 522/// \returns The variable from which the field access should begin, 523/// for an anonymous struct/union that is not a member of another 524/// class. Otherwise, returns NULL. 525VarDecl *Sema::BuildAnonymousStructUnionMemberPath(FieldDecl *Field, 526 llvm::SmallVectorImpl<FieldDecl *> &Path) { 527 assert(Field->getDeclContext()->isRecord() && 528 cast<RecordDecl>(Field->getDeclContext())->isAnonymousStructOrUnion() 529 && "Field must be stored inside an anonymous struct or union"); 530 531 Path.push_back(Field); 532 VarDecl *BaseObject = 0; 533 DeclContext *Ctx = Field->getDeclContext(); 534 do { 535 RecordDecl *Record = cast<RecordDecl>(Ctx); 536 ValueDecl *AnonObject = Record->getAnonymousStructOrUnionObject(); 537 if (FieldDecl *AnonField = dyn_cast<FieldDecl>(AnonObject)) 538 Path.push_back(AnonField); 539 else { 540 BaseObject = cast<VarDecl>(AnonObject); 541 break; 542 } 543 Ctx = Ctx->getParent(); 544 } while (Ctx->isRecord() && 545 cast<RecordDecl>(Ctx)->isAnonymousStructOrUnion()); 546 547 return BaseObject; 548} 549 550ExprResult 551Sema::BuildAnonymousStructUnionMemberReference(SourceLocation Loc, 552 FieldDecl *Field, 553 Expr *BaseObjectExpr, 554 SourceLocation OpLoc) { 555 llvm::SmallVector<FieldDecl *, 4> AnonFields; 556 VarDecl *BaseObject = BuildAnonymousStructUnionMemberPath(Field, 557 AnonFields); 558 559 // Build the expression that refers to the base object, from 560 // which we will build a sequence of member references to each 561 // of the anonymous union objects and, eventually, the field we 562 // found via name lookup. 563 bool BaseObjectIsPointer = false; 564 Qualifiers BaseQuals; 565 if (BaseObject) { 566 // BaseObject is an anonymous struct/union variable (and is, 567 // therefore, not part of another non-anonymous record). 568 MarkDeclarationReferenced(Loc, BaseObject); 569 BaseObjectExpr = new (Context) DeclRefExpr(BaseObject,BaseObject->getType(), 570 SourceLocation()); 571 BaseQuals 572 = Context.getCanonicalType(BaseObject->getType()).getQualifiers(); 573 } else if (BaseObjectExpr) { 574 // The caller provided the base object expression. Determine 575 // whether its a pointer and whether it adds any qualifiers to the 576 // anonymous struct/union fields we're looking into. 577 QualType ObjectType = BaseObjectExpr->getType(); 578 if (const PointerType *ObjectPtr = ObjectType->getAs<PointerType>()) { 579 BaseObjectIsPointer = true; 580 ObjectType = ObjectPtr->getPointeeType(); 581 } 582 BaseQuals 583 = Context.getCanonicalType(ObjectType).getQualifiers(); 584 } else { 585 // We've found a member of an anonymous struct/union that is 586 // inside a non-anonymous struct/union, so in a well-formed 587 // program our base object expression is "this". 588 DeclContext *DC = getFunctionLevelDeclContext(); 589 if (CXXMethodDecl *MD = dyn_cast<CXXMethodDecl>(DC)) { 590 if (!MD->isStatic()) { 591 QualType AnonFieldType 592 = Context.getTagDeclType( 593 cast<RecordDecl>(AnonFields.back()->getDeclContext())); 594 QualType ThisType = Context.getTagDeclType(MD->getParent()); 595 if ((Context.getCanonicalType(AnonFieldType) 596 == Context.getCanonicalType(ThisType)) || 597 IsDerivedFrom(ThisType, AnonFieldType)) { 598 // Our base object expression is "this". 599 BaseObjectExpr = new (Context) CXXThisExpr(Loc, 600 MD->getThisType(Context), 601 /*isImplicit=*/true); 602 BaseObjectIsPointer = true; 603 } 604 } else { 605 return ExprError(Diag(Loc,diag::err_invalid_member_use_in_static_method) 606 << Field->getDeclName()); 607 } 608 BaseQuals = Qualifiers::fromCVRMask(MD->getTypeQualifiers()); 609 } 610 611 if (!BaseObjectExpr) 612 return ExprError(Diag(Loc, diag::err_invalid_non_static_member_use) 613 << Field->getDeclName()); 614 } 615 616 // Build the implicit member references to the field of the 617 // anonymous struct/union. 618 Expr *Result = BaseObjectExpr; 619 Qualifiers ResultQuals = BaseQuals; 620 for (llvm::SmallVector<FieldDecl *, 4>::reverse_iterator 621 FI = AnonFields.rbegin(), FIEnd = AnonFields.rend(); 622 FI != FIEnd; ++FI) { 623 QualType MemberType = (*FI)->getType(); 624 Qualifiers MemberTypeQuals = 625 Context.getCanonicalType(MemberType).getQualifiers(); 626 627 // CVR attributes from the base are picked up by members, 628 // except that 'mutable' members don't pick up 'const'. 629 if ((*FI)->isMutable()) 630 ResultQuals.removeConst(); 631 632 // GC attributes are never picked up by members. 633 ResultQuals.removeObjCGCAttr(); 634 635 // TR 18037 does not allow fields to be declared with address spaces. 636 assert(!MemberTypeQuals.hasAddressSpace()); 637 638 Qualifiers NewQuals = ResultQuals + MemberTypeQuals; 639 if (NewQuals != MemberTypeQuals) 640 MemberType = Context.getQualifiedType(MemberType, NewQuals); 641 642 MarkDeclarationReferenced(Loc, *FI); 643 PerformObjectMemberConversion(Result, /*FIXME:Qualifier=*/0, *FI, *FI); 644 // FIXME: Might this end up being a qualified name? 645 Result = new (Context) MemberExpr(Result, BaseObjectIsPointer, *FI, 646 OpLoc, MemberType); 647 BaseObjectIsPointer = false; 648 ResultQuals = NewQuals; 649 } 650 651 return Owned(Result); 652} 653 654/// Decomposes the given name into a DeclarationNameInfo, its location, and 655/// possibly a list of template arguments. 656/// 657/// If this produces template arguments, it is permitted to call 658/// DecomposeTemplateName. 659/// 660/// This actually loses a lot of source location information for 661/// non-standard name kinds; we should consider preserving that in 662/// some way. 663static void DecomposeUnqualifiedId(Sema &SemaRef, 664 const UnqualifiedId &Id, 665 TemplateArgumentListInfo &Buffer, 666 DeclarationNameInfo &NameInfo, 667 const TemplateArgumentListInfo *&TemplateArgs) { 668 if (Id.getKind() == UnqualifiedId::IK_TemplateId) { 669 Buffer.setLAngleLoc(Id.TemplateId->LAngleLoc); 670 Buffer.setRAngleLoc(Id.TemplateId->RAngleLoc); 671 672 ASTTemplateArgsPtr TemplateArgsPtr(SemaRef, 673 Id.TemplateId->getTemplateArgs(), 674 Id.TemplateId->NumArgs); 675 SemaRef.translateTemplateArguments(TemplateArgsPtr, Buffer); 676 TemplateArgsPtr.release(); 677 678 TemplateName TName = Id.TemplateId->Template.get(); 679 SourceLocation TNameLoc = Id.TemplateId->TemplateNameLoc; 680 NameInfo = SemaRef.Context.getNameForTemplate(TName, TNameLoc); 681 TemplateArgs = &Buffer; 682 } else { 683 NameInfo = SemaRef.GetNameFromUnqualifiedId(Id); 684 TemplateArgs = 0; 685 } 686} 687 688/// Determines whether the given record is "fully-formed" at the given 689/// location, i.e. whether a qualified lookup into it is assured of 690/// getting consistent results already. 691static bool IsFullyFormedScope(Sema &SemaRef, CXXRecordDecl *Record) { 692 if (!Record->hasDefinition()) 693 return false; 694 695 for (CXXRecordDecl::base_class_iterator I = Record->bases_begin(), 696 E = Record->bases_end(); I != E; ++I) { 697 CanQualType BaseT = SemaRef.Context.getCanonicalType((*I).getType()); 698 CanQual<RecordType> BaseRT = BaseT->getAs<RecordType>(); 699 if (!BaseRT) return false; 700 701 CXXRecordDecl *BaseRecord = cast<CXXRecordDecl>(BaseRT->getDecl()); 702 if (!BaseRecord->hasDefinition() || 703 !IsFullyFormedScope(SemaRef, BaseRecord)) 704 return false; 705 } 706 707 return true; 708} 709 710/// Determines if the given class is provably not derived from all of 711/// the prospective base classes. 712static bool IsProvablyNotDerivedFrom(Sema &SemaRef, 713 CXXRecordDecl *Record, 714 const llvm::SmallPtrSet<CXXRecordDecl*, 4> &Bases) { 715 if (Bases.count(Record->getCanonicalDecl())) 716 return false; 717 718 RecordDecl *RD = Record->getDefinition(); 719 if (!RD) return false; 720 Record = cast<CXXRecordDecl>(RD); 721 722 for (CXXRecordDecl::base_class_iterator I = Record->bases_begin(), 723 E = Record->bases_end(); I != E; ++I) { 724 CanQualType BaseT = SemaRef.Context.getCanonicalType((*I).getType()); 725 CanQual<RecordType> BaseRT = BaseT->getAs<RecordType>(); 726 if (!BaseRT) return false; 727 728 CXXRecordDecl *BaseRecord = cast<CXXRecordDecl>(BaseRT->getDecl()); 729 if (!IsProvablyNotDerivedFrom(SemaRef, BaseRecord, Bases)) 730 return false; 731 } 732 733 return true; 734} 735 736enum IMAKind { 737 /// The reference is definitely not an instance member access. 738 IMA_Static, 739 740 /// The reference may be an implicit instance member access. 741 IMA_Mixed, 742 743 /// The reference may be to an instance member, but it is invalid if 744 /// so, because the context is not an instance method. 745 IMA_Mixed_StaticContext, 746 747 /// The reference may be to an instance member, but it is invalid if 748 /// so, because the context is from an unrelated class. 749 IMA_Mixed_Unrelated, 750 751 /// The reference is definitely an implicit instance member access. 752 IMA_Instance, 753 754 /// The reference may be to an unresolved using declaration. 755 IMA_Unresolved, 756 757 /// The reference may be to an unresolved using declaration and the 758 /// context is not an instance method. 759 IMA_Unresolved_StaticContext, 760 761 /// The reference is to a member of an anonymous structure in a 762 /// non-class context. 763 IMA_AnonymousMember, 764 765 /// All possible referrents are instance members and the current 766 /// context is not an instance method. 767 IMA_Error_StaticContext, 768 769 /// All possible referrents are instance members of an unrelated 770 /// class. 771 IMA_Error_Unrelated 772}; 773 774/// The given lookup names class member(s) and is not being used for 775/// an address-of-member expression. Classify the type of access 776/// according to whether it's possible that this reference names an 777/// instance member. This is best-effort; it is okay to 778/// conservatively answer "yes", in which case some errors will simply 779/// not be caught until template-instantiation. 780static IMAKind ClassifyImplicitMemberAccess(Sema &SemaRef, 781 const LookupResult &R) { 782 assert(!R.empty() && (*R.begin())->isCXXClassMember()); 783 784 DeclContext *DC = SemaRef.getFunctionLevelDeclContext(); 785 bool isStaticContext = 786 (!isa<CXXMethodDecl>(DC) || 787 cast<CXXMethodDecl>(DC)->isStatic()); 788 789 if (R.isUnresolvableResult()) 790 return isStaticContext ? IMA_Unresolved_StaticContext : IMA_Unresolved; 791 792 // Collect all the declaring classes of instance members we find. 793 bool hasNonInstance = false; 794 llvm::SmallPtrSet<CXXRecordDecl*, 4> Classes; 795 for (LookupResult::iterator I = R.begin(), E = R.end(); I != E; ++I) { 796 NamedDecl *D = *I; 797 if (D->isCXXInstanceMember()) { 798 CXXRecordDecl *R = cast<CXXRecordDecl>(D->getDeclContext()); 799 800 // If this is a member of an anonymous record, move out to the 801 // innermost non-anonymous struct or union. If there isn't one, 802 // that's a special case. 803 while (R->isAnonymousStructOrUnion()) { 804 R = dyn_cast<CXXRecordDecl>(R->getParent()); 805 if (!R) return IMA_AnonymousMember; 806 } 807 Classes.insert(R->getCanonicalDecl()); 808 } 809 else 810 hasNonInstance = true; 811 } 812 813 // If we didn't find any instance members, it can't be an implicit 814 // member reference. 815 if (Classes.empty()) 816 return IMA_Static; 817 818 // If the current context is not an instance method, it can't be 819 // an implicit member reference. 820 if (isStaticContext) 821 return (hasNonInstance ? IMA_Mixed_StaticContext : IMA_Error_StaticContext); 822 823 // If we can prove that the current context is unrelated to all the 824 // declaring classes, it can't be an implicit member reference (in 825 // which case it's an error if any of those members are selected). 826 if (IsProvablyNotDerivedFrom(SemaRef, 827 cast<CXXMethodDecl>(DC)->getParent(), 828 Classes)) 829 return (hasNonInstance ? IMA_Mixed_Unrelated : IMA_Error_Unrelated); 830 831 return (hasNonInstance ? IMA_Mixed : IMA_Instance); 832} 833 834/// Diagnose a reference to a field with no object available. 835static void DiagnoseInstanceReference(Sema &SemaRef, 836 const CXXScopeSpec &SS, 837 const LookupResult &R) { 838 SourceLocation Loc = R.getNameLoc(); 839 SourceRange Range(Loc); 840 if (SS.isSet()) Range.setBegin(SS.getRange().getBegin()); 841 842 if (R.getAsSingle<FieldDecl>()) { 843 if (CXXMethodDecl *MD = dyn_cast<CXXMethodDecl>(SemaRef.CurContext)) { 844 if (MD->isStatic()) { 845 // "invalid use of member 'x' in static member function" 846 SemaRef.Diag(Loc, diag::err_invalid_member_use_in_static_method) 847 << Range << R.getLookupName(); 848 return; 849 } 850 } 851 852 SemaRef.Diag(Loc, diag::err_invalid_non_static_member_use) 853 << R.getLookupName() << Range; 854 return; 855 } 856 857 SemaRef.Diag(Loc, diag::err_member_call_without_object) << Range; 858} 859 860/// Diagnose an empty lookup. 861/// 862/// \return false if new lookup candidates were found 863bool Sema::DiagnoseEmptyLookup(Scope *S, CXXScopeSpec &SS, LookupResult &R, 864 CorrectTypoContext CTC) { 865 DeclarationName Name = R.getLookupName(); 866 867 unsigned diagnostic = diag::err_undeclared_var_use; 868 unsigned diagnostic_suggest = diag::err_undeclared_var_use_suggest; 869 if (Name.getNameKind() == DeclarationName::CXXOperatorName || 870 Name.getNameKind() == DeclarationName::CXXLiteralOperatorName || 871 Name.getNameKind() == DeclarationName::CXXConversionFunctionName) { 872 diagnostic = diag::err_undeclared_use; 873 diagnostic_suggest = diag::err_undeclared_use_suggest; 874 } 875 876 // If the original lookup was an unqualified lookup, fake an 877 // unqualified lookup. This is useful when (for example) the 878 // original lookup would not have found something because it was a 879 // dependent name. 880 for (DeclContext *DC = SS.isEmpty() ? CurContext : 0; 881 DC; DC = DC->getParent()) { 882 if (isa<CXXRecordDecl>(DC)) { 883 LookupQualifiedName(R, DC); 884 885 if (!R.empty()) { 886 // Don't give errors about ambiguities in this lookup. 887 R.suppressDiagnostics(); 888 889 CXXMethodDecl *CurMethod = dyn_cast<CXXMethodDecl>(CurContext); 890 bool isInstance = CurMethod && 891 CurMethod->isInstance() && 892 DC == CurMethod->getParent(); 893 894 // Give a code modification hint to insert 'this->'. 895 // TODO: fixit for inserting 'Base<T>::' in the other cases. 896 // Actually quite difficult! 897 if (isInstance) { 898 UnresolvedLookupExpr *ULE = cast<UnresolvedLookupExpr>( 899 CallsUndergoingInstantiation.back()->getCallee()); 900 CXXMethodDecl *DepMethod = cast_or_null<CXXMethodDecl>( 901 CurMethod->getInstantiatedFromMemberFunction()); 902 if (DepMethod) { 903 Diag(R.getNameLoc(), diagnostic) << Name 904 << FixItHint::CreateInsertion(R.getNameLoc(), "this->"); 905 QualType DepThisType = DepMethod->getThisType(Context); 906 CXXThisExpr *DepThis = new (Context) CXXThisExpr( 907 R.getNameLoc(), DepThisType, false); 908 TemplateArgumentListInfo TList; 909 if (ULE->hasExplicitTemplateArgs()) 910 ULE->copyTemplateArgumentsInto(TList); 911 CXXDependentScopeMemberExpr *DepExpr = 912 CXXDependentScopeMemberExpr::Create( 913 Context, DepThis, DepThisType, true, SourceLocation(), 914 ULE->getQualifier(), ULE->getQualifierRange(), NULL, 915 R.getLookupNameInfo(), &TList); 916 CallsUndergoingInstantiation.back()->setCallee(DepExpr); 917 } else { 918 // FIXME: we should be able to handle this case too. It is correct 919 // to add this-> here. This is a workaround for PR7947. 920 Diag(R.getNameLoc(), diagnostic) << Name; 921 } 922 } else { 923 Diag(R.getNameLoc(), diagnostic) << Name; 924 } 925 926 // Do we really want to note all of these? 927 for (LookupResult::iterator I = R.begin(), E = R.end(); I != E; ++I) 928 Diag((*I)->getLocation(), diag::note_dependent_var_use); 929 930 // Tell the callee to try to recover. 931 return false; 932 } 933 934 R.clear(); 935 } 936 } 937 938 // We didn't find anything, so try to correct for a typo. 939 DeclarationName Corrected; 940 if (S && (Corrected = CorrectTypo(R, S, &SS, 0, false, CTC))) { 941 if (!R.empty()) { 942 if (isa<ValueDecl>(*R.begin()) || isa<FunctionTemplateDecl>(*R.begin())) { 943 if (SS.isEmpty()) 944 Diag(R.getNameLoc(), diagnostic_suggest) << Name << R.getLookupName() 945 << FixItHint::CreateReplacement(R.getNameLoc(), 946 R.getLookupName().getAsString()); 947 else 948 Diag(R.getNameLoc(), diag::err_no_member_suggest) 949 << Name << computeDeclContext(SS, false) << R.getLookupName() 950 << SS.getRange() 951 << FixItHint::CreateReplacement(R.getNameLoc(), 952 R.getLookupName().getAsString()); 953 if (NamedDecl *ND = R.getAsSingle<NamedDecl>()) 954 Diag(ND->getLocation(), diag::note_previous_decl) 955 << ND->getDeclName(); 956 957 // Tell the callee to try to recover. 958 return false; 959 } 960 961 if (isa<TypeDecl>(*R.begin()) || isa<ObjCInterfaceDecl>(*R.begin())) { 962 // FIXME: If we ended up with a typo for a type name or 963 // Objective-C class name, we're in trouble because the parser 964 // is in the wrong place to recover. Suggest the typo 965 // correction, but don't make it a fix-it since we're not going 966 // to recover well anyway. 967 if (SS.isEmpty()) 968 Diag(R.getNameLoc(), diagnostic_suggest) << Name << R.getLookupName(); 969 else 970 Diag(R.getNameLoc(), diag::err_no_member_suggest) 971 << Name << computeDeclContext(SS, false) << R.getLookupName() 972 << SS.getRange(); 973 974 // Don't try to recover; it won't work. 975 return true; 976 } 977 } else { 978 // FIXME: We found a keyword. Suggest it, but don't provide a fix-it 979 // because we aren't able to recover. 980 if (SS.isEmpty()) 981 Diag(R.getNameLoc(), diagnostic_suggest) << Name << Corrected; 982 else 983 Diag(R.getNameLoc(), diag::err_no_member_suggest) 984 << Name << computeDeclContext(SS, false) << Corrected 985 << SS.getRange(); 986 return true; 987 } 988 R.clear(); 989 } 990 991 // Emit a special diagnostic for failed member lookups. 992 // FIXME: computing the declaration context might fail here (?) 993 if (!SS.isEmpty()) { 994 Diag(R.getNameLoc(), diag::err_no_member) 995 << Name << computeDeclContext(SS, false) 996 << SS.getRange(); 997 return true; 998 } 999 1000 // Give up, we can't recover. 1001 Diag(R.getNameLoc(), diagnostic) << Name; 1002 return true; 1003} 1004 1005static ObjCPropertyDecl *OkToSynthesizeProvisionalIvar(Sema &SemaRef, 1006 IdentifierInfo *II, 1007 SourceLocation NameLoc) { 1008 ObjCMethodDecl *CurMeth = SemaRef.getCurMethodDecl(); 1009 ObjCInterfaceDecl *IDecl = CurMeth->getClassInterface(); 1010 if (!IDecl) 1011 return 0; 1012 ObjCImplementationDecl *ClassImpDecl = IDecl->getImplementation(); 1013 if (!ClassImpDecl) 1014 return 0; 1015 ObjCPropertyDecl *property = SemaRef.LookupPropertyDecl(IDecl, II); 1016 if (!property) 1017 return 0; 1018 if (ObjCPropertyImplDecl *PIDecl = ClassImpDecl->FindPropertyImplDecl(II)) 1019 if (PIDecl->getPropertyImplementation() == ObjCPropertyImplDecl::Dynamic) 1020 return 0; 1021 return property; 1022} 1023 1024static ObjCIvarDecl *SynthesizeProvisionalIvar(Sema &SemaRef, 1025 LookupResult &Lookup, 1026 IdentifierInfo *II, 1027 SourceLocation NameLoc) { 1028 ObjCMethodDecl *CurMeth = SemaRef.getCurMethodDecl(); 1029 bool LookForIvars; 1030 if (Lookup.empty()) 1031 LookForIvars = true; 1032 else if (CurMeth->isClassMethod()) 1033 LookForIvars = false; 1034 else 1035 LookForIvars = (Lookup.isSingleResult() && 1036 Lookup.getFoundDecl()->isDefinedOutsideFunctionOrMethod()); 1037 if (!LookForIvars) 1038 return 0; 1039 1040 ObjCInterfaceDecl *IDecl = CurMeth->getClassInterface(); 1041 if (!IDecl) 1042 return 0; 1043 ObjCImplementationDecl *ClassImpDecl = IDecl->getImplementation(); 1044 if (!ClassImpDecl) 1045 return 0; 1046 bool DynamicImplSeen = false; 1047 ObjCPropertyDecl *property = SemaRef.LookupPropertyDecl(IDecl, II); 1048 if (!property) 1049 return 0; 1050 if (ObjCPropertyImplDecl *PIDecl = ClassImpDecl->FindPropertyImplDecl(II)) 1051 DynamicImplSeen = 1052 (PIDecl->getPropertyImplementation() == ObjCPropertyImplDecl::Dynamic); 1053 if (!DynamicImplSeen) { 1054 QualType PropType = SemaRef.Context.getCanonicalType(property->getType()); 1055 ObjCIvarDecl *Ivar = ObjCIvarDecl::Create(SemaRef.Context, ClassImpDecl, 1056 NameLoc, 1057 II, PropType, /*Dinfo=*/0, 1058 ObjCIvarDecl::Protected, 1059 (Expr *)0, true); 1060 ClassImpDecl->addDecl(Ivar); 1061 IDecl->makeDeclVisibleInContext(Ivar, false); 1062 property->setPropertyIvarDecl(Ivar); 1063 return Ivar; 1064 } 1065 return 0; 1066} 1067 1068ExprResult Sema::ActOnIdExpression(Scope *S, 1069 CXXScopeSpec &SS, 1070 UnqualifiedId &Id, 1071 bool HasTrailingLParen, 1072 bool isAddressOfOperand) { 1073 assert(!(isAddressOfOperand && HasTrailingLParen) && 1074 "cannot be direct & operand and have a trailing lparen"); 1075 1076 if (SS.isInvalid()) 1077 return ExprError(); 1078 1079 TemplateArgumentListInfo TemplateArgsBuffer; 1080 1081 // Decompose the UnqualifiedId into the following data. 1082 DeclarationNameInfo NameInfo; 1083 const TemplateArgumentListInfo *TemplateArgs; 1084 DecomposeUnqualifiedId(*this, Id, TemplateArgsBuffer, NameInfo, TemplateArgs); 1085 1086 DeclarationName Name = NameInfo.getName(); 1087 IdentifierInfo *II = Name.getAsIdentifierInfo(); 1088 SourceLocation NameLoc = NameInfo.getLoc(); 1089 1090 // C++ [temp.dep.expr]p3: 1091 // An id-expression is type-dependent if it contains: 1092 // -- an identifier that was declared with a dependent type, 1093 // (note: handled after lookup) 1094 // -- a template-id that is dependent, 1095 // (note: handled in BuildTemplateIdExpr) 1096 // -- a conversion-function-id that specifies a dependent type, 1097 // -- a nested-name-specifier that contains a class-name that 1098 // names a dependent type. 1099 // Determine whether this is a member of an unknown specialization; 1100 // we need to handle these differently. 1101 bool DependentID = false; 1102 if (Name.getNameKind() == DeclarationName::CXXConversionFunctionName && 1103 Name.getCXXNameType()->isDependentType()) { 1104 DependentID = true; 1105 } else if (SS.isSet()) { 1106 DeclContext *DC = computeDeclContext(SS, false); 1107 if (DC) { 1108 if (RequireCompleteDeclContext(SS, DC)) 1109 return ExprError(); 1110 // FIXME: We should be checking whether DC is the current instantiation. 1111 if (CXXRecordDecl *RD = dyn_cast<CXXRecordDecl>(DC)) 1112 DependentID = !IsFullyFormedScope(*this, RD); 1113 } else { 1114 DependentID = true; 1115 } 1116 } 1117 1118 if (DependentID) { 1119 return ActOnDependentIdExpression(SS, NameInfo, isAddressOfOperand, 1120 TemplateArgs); 1121 } 1122 bool IvarLookupFollowUp = false; 1123 // Perform the required lookup. 1124 LookupResult R(*this, NameInfo, LookupOrdinaryName); 1125 if (TemplateArgs) { 1126 // Lookup the template name again to correctly establish the context in 1127 // which it was found. This is really unfortunate as we already did the 1128 // lookup to determine that it was a template name in the first place. If 1129 // this becomes a performance hit, we can work harder to preserve those 1130 // results until we get here but it's likely not worth it. 1131 bool MemberOfUnknownSpecialization; 1132 LookupTemplateName(R, S, SS, QualType(), /*EnteringContext=*/false, 1133 MemberOfUnknownSpecialization); 1134 } else { 1135 IvarLookupFollowUp = (!SS.isSet() && II && getCurMethodDecl()); 1136 LookupParsedName(R, S, &SS, !IvarLookupFollowUp); 1137 1138 // If this reference is in an Objective-C method, then we need to do 1139 // some special Objective-C lookup, too. 1140 if (IvarLookupFollowUp) { 1141 ExprResult E(LookupInObjCMethod(R, S, II, true)); 1142 if (E.isInvalid()) 1143 return ExprError(); 1144 1145 Expr *Ex = E.takeAs<Expr>(); 1146 if (Ex) return Owned(Ex); 1147 // Synthesize ivars lazily 1148 if (getLangOptions().ObjCNonFragileABI2) { 1149 if (SynthesizeProvisionalIvar(*this, R, II, NameLoc)) 1150 return ActOnIdExpression(S, SS, Id, HasTrailingLParen, 1151 isAddressOfOperand); 1152 } 1153 // for further use, this must be set to false if in class method. 1154 IvarLookupFollowUp = getCurMethodDecl()->isInstanceMethod(); 1155 } 1156 } 1157 1158 if (R.isAmbiguous()) 1159 return ExprError(); 1160 1161 // Determine whether this name might be a candidate for 1162 // argument-dependent lookup. 1163 bool ADL = UseArgumentDependentLookup(SS, R, HasTrailingLParen); 1164 1165 if (R.empty() && !ADL) { 1166 // Otherwise, this could be an implicitly declared function reference (legal 1167 // in C90, extension in C99, forbidden in C++). 1168 if (HasTrailingLParen && II && !getLangOptions().CPlusPlus) { 1169 NamedDecl *D = ImplicitlyDefineFunction(NameLoc, *II, S); 1170 if (D) R.addDecl(D); 1171 } 1172 1173 // If this name wasn't predeclared and if this is not a function 1174 // call, diagnose the problem. 1175 if (R.empty()) { 1176 if (DiagnoseEmptyLookup(S, SS, R, CTC_Unknown)) 1177 return ExprError(); 1178 1179 assert(!R.empty() && 1180 "DiagnoseEmptyLookup returned false but added no results"); 1181 1182 // If we found an Objective-C instance variable, let 1183 // LookupInObjCMethod build the appropriate expression to 1184 // reference the ivar. 1185 if (ObjCIvarDecl *Ivar = R.getAsSingle<ObjCIvarDecl>()) { 1186 R.clear(); 1187 ExprResult E(LookupInObjCMethod(R, S, Ivar->getIdentifier())); 1188 assert(E.isInvalid() || E.get()); 1189 return move(E); 1190 } 1191 } 1192 } 1193 1194 // This is guaranteed from this point on. 1195 assert(!R.empty() || ADL); 1196 1197 if (VarDecl *Var = R.getAsSingle<VarDecl>()) { 1198 if (getLangOptions().ObjCNonFragileABI && IvarLookupFollowUp && 1199 !getLangOptions().ObjCNonFragileABI2 && 1200 Var->isFileVarDecl()) { 1201 ObjCPropertyDecl *Property = 1202 OkToSynthesizeProvisionalIvar(*this, II, NameLoc); 1203 if (Property) { 1204 Diag(NameLoc, diag::warn_ivar_variable_conflict) << Var->getDeclName(); 1205 Diag(Property->getLocation(), diag::note_property_declare); 1206 Diag(Var->getLocation(), diag::note_global_declared_at); 1207 } 1208 } 1209 } else if (FunctionDecl *Func = R.getAsSingle<FunctionDecl>()) { 1210 if (!getLangOptions().CPlusPlus && !Func->hasPrototype()) { 1211 // C99 DR 316 says that, if a function type comes from a 1212 // function definition (without a prototype), that type is only 1213 // used for checking compatibility. Therefore, when referencing 1214 // the function, we pretend that we don't have the full function 1215 // type. 1216 if (DiagnoseUseOfDecl(Func, NameLoc)) 1217 return ExprError(); 1218 1219 QualType T = Func->getType(); 1220 QualType NoProtoType = T; 1221 if (const FunctionProtoType *Proto = T->getAs<FunctionProtoType>()) 1222 NoProtoType = Context.getFunctionNoProtoType(Proto->getResultType(), 1223 Proto->getExtInfo()); 1224 return BuildDeclRefExpr(Func, NoProtoType, NameLoc, &SS); 1225 } 1226 } 1227 1228 // Check whether this might be a C++ implicit instance member access. 1229 // C++ [class.mfct.non-static]p3: 1230 // When an id-expression that is not part of a class member access 1231 // syntax and not used to form a pointer to member is used in the 1232 // body of a non-static member function of class X, if name lookup 1233 // resolves the name in the id-expression to a non-static non-type 1234 // member of some class C, the id-expression is transformed into a 1235 // class member access expression using (*this) as the 1236 // postfix-expression to the left of the . operator. 1237 // 1238 // But we don't actually need to do this for '&' operands if R 1239 // resolved to a function or overloaded function set, because the 1240 // expression is ill-formed if it actually works out to be a 1241 // non-static member function: 1242 // 1243 // C++ [expr.ref]p4: 1244 // Otherwise, if E1.E2 refers to a non-static member function. . . 1245 // [t]he expression can be used only as the left-hand operand of a 1246 // member function call. 1247 // 1248 // There are other safeguards against such uses, but it's important 1249 // to get this right here so that we don't end up making a 1250 // spuriously dependent expression if we're inside a dependent 1251 // instance method. 1252 if (!R.empty() && (*R.begin())->isCXXClassMember()) { 1253 bool MightBeImplicitMember; 1254 if (!isAddressOfOperand) 1255 MightBeImplicitMember = true; 1256 else if (!SS.isEmpty()) 1257 MightBeImplicitMember = false; 1258 else if (R.isOverloadedResult()) 1259 MightBeImplicitMember = false; 1260 else if (R.isUnresolvableResult()) 1261 MightBeImplicitMember = true; 1262 else 1263 MightBeImplicitMember = isa<FieldDecl>(R.getFoundDecl()); 1264 1265 if (MightBeImplicitMember) 1266 return BuildPossibleImplicitMemberExpr(SS, R, TemplateArgs); 1267 } 1268 1269 if (TemplateArgs) 1270 return BuildTemplateIdExpr(SS, R, ADL, *TemplateArgs); 1271 1272 return BuildDeclarationNameExpr(SS, R, ADL); 1273} 1274 1275/// Builds an expression which might be an implicit member expression. 1276ExprResult 1277Sema::BuildPossibleImplicitMemberExpr(const CXXScopeSpec &SS, 1278 LookupResult &R, 1279 const TemplateArgumentListInfo *TemplateArgs) { 1280 switch (ClassifyImplicitMemberAccess(*this, R)) { 1281 case IMA_Instance: 1282 return BuildImplicitMemberExpr(SS, R, TemplateArgs, true); 1283 1284 case IMA_AnonymousMember: 1285 assert(R.isSingleResult()); 1286 return BuildAnonymousStructUnionMemberReference(R.getNameLoc(), 1287 R.getAsSingle<FieldDecl>()); 1288 1289 case IMA_Mixed: 1290 case IMA_Mixed_Unrelated: 1291 case IMA_Unresolved: 1292 return BuildImplicitMemberExpr(SS, R, TemplateArgs, false); 1293 1294 case IMA_Static: 1295 case IMA_Mixed_StaticContext: 1296 case IMA_Unresolved_StaticContext: 1297 if (TemplateArgs) 1298 return BuildTemplateIdExpr(SS, R, false, *TemplateArgs); 1299 return BuildDeclarationNameExpr(SS, R, false); 1300 1301 case IMA_Error_StaticContext: 1302 case IMA_Error_Unrelated: 1303 DiagnoseInstanceReference(*this, SS, R); 1304 return ExprError(); 1305 } 1306 1307 llvm_unreachable("unexpected instance member access kind"); 1308 return ExprError(); 1309} 1310 1311/// BuildQualifiedDeclarationNameExpr - Build a C++ qualified 1312/// declaration name, generally during template instantiation. 1313/// There's a large number of things which don't need to be done along 1314/// this path. 1315ExprResult 1316Sema::BuildQualifiedDeclarationNameExpr(CXXScopeSpec &SS, 1317 const DeclarationNameInfo &NameInfo) { 1318 DeclContext *DC; 1319 if (!(DC = computeDeclContext(SS, false)) || DC->isDependentContext()) 1320 return BuildDependentDeclRefExpr(SS, NameInfo, 0); 1321 1322 if (RequireCompleteDeclContext(SS, DC)) 1323 return ExprError(); 1324 1325 LookupResult R(*this, NameInfo, LookupOrdinaryName); 1326 LookupQualifiedName(R, DC); 1327 1328 if (R.isAmbiguous()) 1329 return ExprError(); 1330 1331 if (R.empty()) { 1332 Diag(NameInfo.getLoc(), diag::err_no_member) 1333 << NameInfo.getName() << DC << SS.getRange(); 1334 return ExprError(); 1335 } 1336 1337 return BuildDeclarationNameExpr(SS, R, /*ADL*/ false); 1338} 1339 1340/// LookupInObjCMethod - The parser has read a name in, and Sema has 1341/// detected that we're currently inside an ObjC method. Perform some 1342/// additional lookup. 1343/// 1344/// Ideally, most of this would be done by lookup, but there's 1345/// actually quite a lot of extra work involved. 1346/// 1347/// Returns a null sentinel to indicate trivial success. 1348ExprResult 1349Sema::LookupInObjCMethod(LookupResult &Lookup, Scope *S, 1350 IdentifierInfo *II, bool AllowBuiltinCreation) { 1351 SourceLocation Loc = Lookup.getNameLoc(); 1352 ObjCMethodDecl *CurMethod = getCurMethodDecl(); 1353 1354 // There are two cases to handle here. 1) scoped lookup could have failed, 1355 // in which case we should look for an ivar. 2) scoped lookup could have 1356 // found a decl, but that decl is outside the current instance method (i.e. 1357 // a global variable). In these two cases, we do a lookup for an ivar with 1358 // this name, if the lookup sucedes, we replace it our current decl. 1359 1360 // If we're in a class method, we don't normally want to look for 1361 // ivars. But if we don't find anything else, and there's an 1362 // ivar, that's an error. 1363 bool IsClassMethod = CurMethod->isClassMethod(); 1364 1365 bool LookForIvars; 1366 if (Lookup.empty()) 1367 LookForIvars = true; 1368 else if (IsClassMethod) 1369 LookForIvars = false; 1370 else 1371 LookForIvars = (Lookup.isSingleResult() && 1372 Lookup.getFoundDecl()->isDefinedOutsideFunctionOrMethod()); 1373 ObjCInterfaceDecl *IFace = 0; 1374 if (LookForIvars) { 1375 IFace = CurMethod->getClassInterface(); 1376 ObjCInterfaceDecl *ClassDeclared; 1377 if (ObjCIvarDecl *IV = IFace->lookupInstanceVariable(II, ClassDeclared)) { 1378 // Diagnose using an ivar in a class method. 1379 if (IsClassMethod) 1380 return ExprError(Diag(Loc, diag::error_ivar_use_in_class_method) 1381 << IV->getDeclName()); 1382 1383 // If we're referencing an invalid decl, just return this as a silent 1384 // error node. The error diagnostic was already emitted on the decl. 1385 if (IV->isInvalidDecl()) 1386 return ExprError(); 1387 1388 // Check if referencing a field with __attribute__((deprecated)). 1389 if (DiagnoseUseOfDecl(IV, Loc)) 1390 return ExprError(); 1391 1392 // Diagnose the use of an ivar outside of the declaring class. 1393 if (IV->getAccessControl() == ObjCIvarDecl::Private && 1394 ClassDeclared != IFace) 1395 Diag(Loc, diag::error_private_ivar_access) << IV->getDeclName(); 1396 1397 // FIXME: This should use a new expr for a direct reference, don't 1398 // turn this into Self->ivar, just return a BareIVarExpr or something. 1399 IdentifierInfo &II = Context.Idents.get("self"); 1400 UnqualifiedId SelfName; 1401 SelfName.setIdentifier(&II, SourceLocation()); 1402 CXXScopeSpec SelfScopeSpec; 1403 ExprResult SelfExpr = ActOnIdExpression(S, SelfScopeSpec, 1404 SelfName, false, false); 1405 if (SelfExpr.isInvalid()) 1406 return ExprError(); 1407 1408 MarkDeclarationReferenced(Loc, IV); 1409 return Owned(new (Context) 1410 ObjCIvarRefExpr(IV, IV->getType(), Loc, 1411 SelfExpr.takeAs<Expr>(), true, true)); 1412 } 1413 } else if (CurMethod->isInstanceMethod()) { 1414 // We should warn if a local variable hides an ivar. 1415 ObjCInterfaceDecl *IFace = CurMethod->getClassInterface(); 1416 ObjCInterfaceDecl *ClassDeclared; 1417 if (ObjCIvarDecl *IV = IFace->lookupInstanceVariable(II, ClassDeclared)) { 1418 if (IV->getAccessControl() != ObjCIvarDecl::Private || 1419 IFace == ClassDeclared) 1420 Diag(Loc, diag::warn_ivar_use_hidden) << IV->getDeclName(); 1421 } 1422 } 1423 1424 if (Lookup.empty() && II && AllowBuiltinCreation) { 1425 // FIXME. Consolidate this with similar code in LookupName. 1426 if (unsigned BuiltinID = II->getBuiltinID()) { 1427 if (!(getLangOptions().CPlusPlus && 1428 Context.BuiltinInfo.isPredefinedLibFunction(BuiltinID))) { 1429 NamedDecl *D = LazilyCreateBuiltin((IdentifierInfo *)II, BuiltinID, 1430 S, Lookup.isForRedeclaration(), 1431 Lookup.getNameLoc()); 1432 if (D) Lookup.addDecl(D); 1433 } 1434 } 1435 } 1436 // Sentinel value saying that we didn't do anything special. 1437 return Owned((Expr*) 0); 1438} 1439 1440/// \brief Cast a base object to a member's actual type. 1441/// 1442/// Logically this happens in three phases: 1443/// 1444/// * First we cast from the base type to the naming class. 1445/// The naming class is the class into which we were looking 1446/// when we found the member; it's the qualifier type if a 1447/// qualifier was provided, and otherwise it's the base type. 1448/// 1449/// * Next we cast from the naming class to the declaring class. 1450/// If the member we found was brought into a class's scope by 1451/// a using declaration, this is that class; otherwise it's 1452/// the class declaring the member. 1453/// 1454/// * Finally we cast from the declaring class to the "true" 1455/// declaring class of the member. This conversion does not 1456/// obey access control. 1457bool 1458Sema::PerformObjectMemberConversion(Expr *&From, 1459 NestedNameSpecifier *Qualifier, 1460 NamedDecl *FoundDecl, 1461 NamedDecl *Member) { 1462 CXXRecordDecl *RD = dyn_cast<CXXRecordDecl>(Member->getDeclContext()); 1463 if (!RD) 1464 return false; 1465 1466 QualType DestRecordType; 1467 QualType DestType; 1468 QualType FromRecordType; 1469 QualType FromType = From->getType(); 1470 bool PointerConversions = false; 1471 if (isa<FieldDecl>(Member)) { 1472 DestRecordType = Context.getCanonicalType(Context.getTypeDeclType(RD)); 1473 1474 if (FromType->getAs<PointerType>()) { 1475 DestType = Context.getPointerType(DestRecordType); 1476 FromRecordType = FromType->getPointeeType(); 1477 PointerConversions = true; 1478 } else { 1479 DestType = DestRecordType; 1480 FromRecordType = FromType; 1481 } 1482 } else if (CXXMethodDecl *Method = dyn_cast<CXXMethodDecl>(Member)) { 1483 if (Method->isStatic()) 1484 return false; 1485 1486 DestType = Method->getThisType(Context); 1487 DestRecordType = DestType->getPointeeType(); 1488 1489 if (FromType->getAs<PointerType>()) { 1490 FromRecordType = FromType->getPointeeType(); 1491 PointerConversions = true; 1492 } else { 1493 FromRecordType = FromType; 1494 DestType = DestRecordType; 1495 } 1496 } else { 1497 // No conversion necessary. 1498 return false; 1499 } 1500 1501 if (DestType->isDependentType() || FromType->isDependentType()) 1502 return false; 1503 1504 // If the unqualified types are the same, no conversion is necessary. 1505 if (Context.hasSameUnqualifiedType(FromRecordType, DestRecordType)) 1506 return false; 1507 1508 SourceRange FromRange = From->getSourceRange(); 1509 SourceLocation FromLoc = FromRange.getBegin(); 1510 1511 ExprValueKind VK = CastCategory(From); 1512 1513 // C++ [class.member.lookup]p8: 1514 // [...] Ambiguities can often be resolved by qualifying a name with its 1515 // class name. 1516 // 1517 // If the member was a qualified name and the qualified referred to a 1518 // specific base subobject type, we'll cast to that intermediate type 1519 // first and then to the object in which the member is declared. That allows 1520 // one to resolve ambiguities in, e.g., a diamond-shaped hierarchy such as: 1521 // 1522 // class Base { public: int x; }; 1523 // class Derived1 : public Base { }; 1524 // class Derived2 : public Base { }; 1525 // class VeryDerived : public Derived1, public Derived2 { void f(); }; 1526 // 1527 // void VeryDerived::f() { 1528 // x = 17; // error: ambiguous base subobjects 1529 // Derived1::x = 17; // okay, pick the Base subobject of Derived1 1530 // } 1531 if (Qualifier) { 1532 QualType QType = QualType(Qualifier->getAsType(), 0); 1533 assert(!QType.isNull() && "lookup done with dependent qualifier?"); 1534 assert(QType->isRecordType() && "lookup done with non-record type"); 1535 1536 QualType QRecordType = QualType(QType->getAs<RecordType>(), 0); 1537 1538 // In C++98, the qualifier type doesn't actually have to be a base 1539 // type of the object type, in which case we just ignore it. 1540 // Otherwise build the appropriate casts. 1541 if (IsDerivedFrom(FromRecordType, QRecordType)) { 1542 CXXCastPath BasePath; 1543 if (CheckDerivedToBaseConversion(FromRecordType, QRecordType, 1544 FromLoc, FromRange, &BasePath)) 1545 return true; 1546 1547 if (PointerConversions) 1548 QType = Context.getPointerType(QType); 1549 ImpCastExprToType(From, QType, CK_UncheckedDerivedToBase, 1550 VK, &BasePath); 1551 1552 FromType = QType; 1553 FromRecordType = QRecordType; 1554 1555 // If the qualifier type was the same as the destination type, 1556 // we're done. 1557 if (Context.hasSameUnqualifiedType(FromRecordType, DestRecordType)) 1558 return false; 1559 } 1560 } 1561 1562 bool IgnoreAccess = false; 1563 1564 // If we actually found the member through a using declaration, cast 1565 // down to the using declaration's type. 1566 // 1567 // Pointer equality is fine here because only one declaration of a 1568 // class ever has member declarations. 1569 if (FoundDecl->getDeclContext() != Member->getDeclContext()) { 1570 assert(isa<UsingShadowDecl>(FoundDecl)); 1571 QualType URecordType = Context.getTypeDeclType( 1572 cast<CXXRecordDecl>(FoundDecl->getDeclContext())); 1573 1574 // We only need to do this if the naming-class to declaring-class 1575 // conversion is non-trivial. 1576 if (!Context.hasSameUnqualifiedType(FromRecordType, URecordType)) { 1577 assert(IsDerivedFrom(FromRecordType, URecordType)); 1578 CXXCastPath BasePath; 1579 if (CheckDerivedToBaseConversion(FromRecordType, URecordType, 1580 FromLoc, FromRange, &BasePath)) 1581 return true; 1582 1583 QualType UType = URecordType; 1584 if (PointerConversions) 1585 UType = Context.getPointerType(UType); 1586 ImpCastExprToType(From, UType, CK_UncheckedDerivedToBase, 1587 VK, &BasePath); 1588 FromType = UType; 1589 FromRecordType = URecordType; 1590 } 1591 1592 // We don't do access control for the conversion from the 1593 // declaring class to the true declaring class. 1594 IgnoreAccess = true; 1595 } 1596 1597 CXXCastPath BasePath; 1598 if (CheckDerivedToBaseConversion(FromRecordType, DestRecordType, 1599 FromLoc, FromRange, &BasePath, 1600 IgnoreAccess)) 1601 return true; 1602 1603 ImpCastExprToType(From, DestType, CK_UncheckedDerivedToBase, 1604 VK, &BasePath); 1605 return false; 1606} 1607 1608/// \brief Build a MemberExpr AST node. 1609static MemberExpr *BuildMemberExpr(ASTContext &C, Expr *Base, bool isArrow, 1610 const CXXScopeSpec &SS, ValueDecl *Member, 1611 DeclAccessPair FoundDecl, 1612 const DeclarationNameInfo &MemberNameInfo, 1613 QualType Ty, 1614 const TemplateArgumentListInfo *TemplateArgs = 0) { 1615 NestedNameSpecifier *Qualifier = 0; 1616 SourceRange QualifierRange; 1617 if (SS.isSet()) { 1618 Qualifier = (NestedNameSpecifier *) SS.getScopeRep(); 1619 QualifierRange = SS.getRange(); 1620 } 1621 1622 return MemberExpr::Create(C, Base, isArrow, Qualifier, QualifierRange, 1623 Member, FoundDecl, MemberNameInfo, 1624 TemplateArgs, Ty); 1625} 1626 1627/// Builds an implicit member access expression. The current context 1628/// is known to be an instance method, and the given unqualified lookup 1629/// set is known to contain only instance members, at least one of which 1630/// is from an appropriate type. 1631ExprResult 1632Sema::BuildImplicitMemberExpr(const CXXScopeSpec &SS, 1633 LookupResult &R, 1634 const TemplateArgumentListInfo *TemplateArgs, 1635 bool IsKnownInstance) { 1636 assert(!R.empty() && !R.isAmbiguous()); 1637 1638 SourceLocation Loc = R.getNameLoc(); 1639 1640 // We may have found a field within an anonymous union or struct 1641 // (C++ [class.union]). 1642 // FIXME: This needs to happen post-isImplicitMemberReference? 1643 // FIXME: template-ids inside anonymous structs? 1644 if (FieldDecl *FD = R.getAsSingle<FieldDecl>()) 1645 if (cast<RecordDecl>(FD->getDeclContext())->isAnonymousStructOrUnion()) 1646 return BuildAnonymousStructUnionMemberReference(Loc, FD); 1647 1648 // If this is known to be an instance access, go ahead and build a 1649 // 'this' expression now. 1650 DeclContext *DC = getFunctionLevelDeclContext(); 1651 QualType ThisType = cast<CXXMethodDecl>(DC)->getThisType(Context); 1652 Expr *This = 0; // null signifies implicit access 1653 if (IsKnownInstance) { 1654 SourceLocation Loc = R.getNameLoc(); 1655 if (SS.getRange().isValid()) 1656 Loc = SS.getRange().getBegin(); 1657 This = new (Context) CXXThisExpr(Loc, ThisType, /*isImplicit=*/true); 1658 } 1659 1660 return BuildMemberReferenceExpr(This, ThisType, 1661 /*OpLoc*/ SourceLocation(), 1662 /*IsArrow*/ true, 1663 SS, 1664 /*FirstQualifierInScope*/ 0, 1665 R, TemplateArgs); 1666} 1667 1668bool Sema::UseArgumentDependentLookup(const CXXScopeSpec &SS, 1669 const LookupResult &R, 1670 bool HasTrailingLParen) { 1671 // Only when used directly as the postfix-expression of a call. 1672 if (!HasTrailingLParen) 1673 return false; 1674 1675 // Never if a scope specifier was provided. 1676 if (SS.isSet()) 1677 return false; 1678 1679 // Only in C++ or ObjC++. 1680 if (!getLangOptions().CPlusPlus) 1681 return false; 1682 1683 // Turn off ADL when we find certain kinds of declarations during 1684 // normal lookup: 1685 for (LookupResult::iterator I = R.begin(), E = R.end(); I != E; ++I) { 1686 NamedDecl *D = *I; 1687 1688 // C++0x [basic.lookup.argdep]p3: 1689 // -- a declaration of a class member 1690 // Since using decls preserve this property, we check this on the 1691 // original decl. 1692 if (D->isCXXClassMember()) 1693 return false; 1694 1695 // C++0x [basic.lookup.argdep]p3: 1696 // -- a block-scope function declaration that is not a 1697 // using-declaration 1698 // NOTE: we also trigger this for function templates (in fact, we 1699 // don't check the decl type at all, since all other decl types 1700 // turn off ADL anyway). 1701 if (isa<UsingShadowDecl>(D)) 1702 D = cast<UsingShadowDecl>(D)->getTargetDecl(); 1703 else if (D->getDeclContext()->isFunctionOrMethod()) 1704 return false; 1705 1706 // C++0x [basic.lookup.argdep]p3: 1707 // -- a declaration that is neither a function or a function 1708 // template 1709 // And also for builtin functions. 1710 if (isa<FunctionDecl>(D)) { 1711 FunctionDecl *FDecl = cast<FunctionDecl>(D); 1712 1713 // But also builtin functions. 1714 if (FDecl->getBuiltinID() && FDecl->isImplicit()) 1715 return false; 1716 } else if (!isa<FunctionTemplateDecl>(D)) 1717 return false; 1718 } 1719 1720 return true; 1721} 1722 1723 1724/// Diagnoses obvious problems with the use of the given declaration 1725/// as an expression. This is only actually called for lookups that 1726/// were not overloaded, and it doesn't promise that the declaration 1727/// will in fact be used. 1728static bool CheckDeclInExpr(Sema &S, SourceLocation Loc, NamedDecl *D) { 1729 if (isa<TypedefDecl>(D)) { 1730 S.Diag(Loc, diag::err_unexpected_typedef) << D->getDeclName(); 1731 return true; 1732 } 1733 1734 if (isa<ObjCInterfaceDecl>(D)) { 1735 S.Diag(Loc, diag::err_unexpected_interface) << D->getDeclName(); 1736 return true; 1737 } 1738 1739 if (isa<NamespaceDecl>(D)) { 1740 S.Diag(Loc, diag::err_unexpected_namespace) << D->getDeclName(); 1741 return true; 1742 } 1743 1744 return false; 1745} 1746 1747ExprResult 1748Sema::BuildDeclarationNameExpr(const CXXScopeSpec &SS, 1749 LookupResult &R, 1750 bool NeedsADL) { 1751 // If this is a single, fully-resolved result and we don't need ADL, 1752 // just build an ordinary singleton decl ref. 1753 if (!NeedsADL && R.isSingleResult() && !R.getAsSingle<FunctionTemplateDecl>()) 1754 return BuildDeclarationNameExpr(SS, R.getLookupNameInfo(), 1755 R.getFoundDecl()); 1756 1757 // We only need to check the declaration if there's exactly one 1758 // result, because in the overloaded case the results can only be 1759 // functions and function templates. 1760 if (R.isSingleResult() && 1761 CheckDeclInExpr(*this, R.getNameLoc(), R.getFoundDecl())) 1762 return ExprError(); 1763 1764 // Otherwise, just build an unresolved lookup expression. Suppress 1765 // any lookup-related diagnostics; we'll hash these out later, when 1766 // we've picked a target. 1767 R.suppressDiagnostics(); 1768 1769 bool Dependent 1770 = UnresolvedLookupExpr::ComputeDependence(R.begin(), R.end(), 0); 1771 UnresolvedLookupExpr *ULE 1772 = UnresolvedLookupExpr::Create(Context, Dependent, R.getNamingClass(), 1773 (NestedNameSpecifier*) SS.getScopeRep(), 1774 SS.getRange(), R.getLookupNameInfo(), 1775 NeedsADL, R.isOverloadedResult(), 1776 R.begin(), R.end()); 1777 1778 return Owned(ULE); 1779} 1780 1781 1782/// \brief Complete semantic analysis for a reference to the given declaration. 1783ExprResult 1784Sema::BuildDeclarationNameExpr(const CXXScopeSpec &SS, 1785 const DeclarationNameInfo &NameInfo, 1786 NamedDecl *D) { 1787 assert(D && "Cannot refer to a NULL declaration"); 1788 assert(!isa<FunctionTemplateDecl>(D) && 1789 "Cannot refer unambiguously to a function template"); 1790 1791 SourceLocation Loc = NameInfo.getLoc(); 1792 if (CheckDeclInExpr(*this, Loc, D)) 1793 return ExprError(); 1794 1795 if (TemplateDecl *Template = dyn_cast<TemplateDecl>(D)) { 1796 // Specifically diagnose references to class templates that are missing 1797 // a template argument list. 1798 Diag(Loc, diag::err_template_decl_ref) 1799 << Template << SS.getRange(); 1800 Diag(Template->getLocation(), diag::note_template_decl_here); 1801 return ExprError(); 1802 } 1803 1804 // Make sure that we're referring to a value. 1805 ValueDecl *VD = dyn_cast<ValueDecl>(D); 1806 if (!VD) { 1807 Diag(Loc, diag::err_ref_non_value) 1808 << D << SS.getRange(); 1809 Diag(D->getLocation(), diag::note_declared_at); 1810 return ExprError(); 1811 } 1812 1813 // Check whether this declaration can be used. Note that we suppress 1814 // this check when we're going to perform argument-dependent lookup 1815 // on this function name, because this might not be the function 1816 // that overload resolution actually selects. 1817 if (DiagnoseUseOfDecl(VD, Loc)) 1818 return ExprError(); 1819 1820 // Only create DeclRefExpr's for valid Decl's. 1821 if (VD->isInvalidDecl()) 1822 return ExprError(); 1823 1824 // If the identifier reference is inside a block, and it refers to a value 1825 // that is outside the block, create a BlockDeclRefExpr instead of a 1826 // DeclRefExpr. This ensures the value is treated as a copy-in snapshot when 1827 // the block is formed. 1828 // 1829 // We do not do this for things like enum constants, global variables, etc, 1830 // as they do not get snapshotted. 1831 // 1832 if (getCurBlock() && 1833 ShouldSnapshotBlockValueReference(*this, getCurBlock(), VD)) { 1834 if (VD->getType().getTypePtr()->isVariablyModifiedType()) { 1835 Diag(Loc, diag::err_ref_vm_type); 1836 Diag(D->getLocation(), diag::note_declared_at); 1837 return ExprError(); 1838 } 1839 1840 if (VD->getType()->isArrayType()) { 1841 Diag(Loc, diag::err_ref_array_type); 1842 Diag(D->getLocation(), diag::note_declared_at); 1843 return ExprError(); 1844 } 1845 1846 MarkDeclarationReferenced(Loc, VD); 1847 QualType ExprTy = VD->getType().getNonReferenceType(); 1848 // The BlocksAttr indicates the variable is bound by-reference. 1849 if (VD->getAttr<BlocksAttr>()) 1850 return Owned(new (Context) BlockDeclRefExpr(VD, ExprTy, Loc, true)); 1851 // This is to record that a 'const' was actually synthesize and added. 1852 bool constAdded = !ExprTy.isConstQualified(); 1853 // Variable will be bound by-copy, make it const within the closure. 1854 1855 ExprTy.addConst(); 1856 QualType T = VD->getType(); 1857 BlockDeclRefExpr *BDRE = new (Context) BlockDeclRefExpr(VD, 1858 ExprTy, Loc, false, 1859 constAdded); 1860 if (getLangOptions().CPlusPlus) { 1861 if (!T->isDependentType() && !T->isReferenceType()) { 1862 Expr *E = new (Context) 1863 DeclRefExpr(const_cast<ValueDecl*>(BDRE->getDecl()), T, 1864 SourceLocation()); 1865 1866 ExprResult Res = PerformCopyInitialization( 1867 InitializedEntity::InitializeBlock(VD->getLocation(), 1868 T, false), 1869 SourceLocation(), 1870 Owned(E)); 1871 if (!Res.isInvalid()) { 1872 Res = MaybeCreateCXXExprWithTemporaries(Res.get()); 1873 Expr *Init = Res.takeAs<Expr>(); 1874 BDRE->setCopyConstructorExpr(Init); 1875 } 1876 } 1877 } 1878 return Owned(BDRE); 1879 } 1880 // If this reference is not in a block or if the referenced variable is 1881 // within the block, create a normal DeclRefExpr. 1882 1883 return BuildDeclRefExpr(VD, VD->getType().getNonReferenceType(), 1884 NameInfo, &SS); 1885} 1886 1887ExprResult Sema::ActOnPredefinedExpr(SourceLocation Loc, 1888 tok::TokenKind Kind) { 1889 PredefinedExpr::IdentType IT; 1890 1891 switch (Kind) { 1892 default: assert(0 && "Unknown simple primary expr!"); 1893 case tok::kw___func__: IT = PredefinedExpr::Func; break; // [C99 6.4.2.2] 1894 case tok::kw___FUNCTION__: IT = PredefinedExpr::Function; break; 1895 case tok::kw___PRETTY_FUNCTION__: IT = PredefinedExpr::PrettyFunction; break; 1896 } 1897 1898 // Pre-defined identifiers are of type char[x], where x is the length of the 1899 // string. 1900 1901 Decl *currentDecl = getCurFunctionOrMethodDecl(); 1902 if (!currentDecl && getCurBlock()) 1903 currentDecl = getCurBlock()->TheDecl; 1904 if (!currentDecl) { 1905 Diag(Loc, diag::ext_predef_outside_function); 1906 currentDecl = Context.getTranslationUnitDecl(); 1907 } 1908 1909 QualType ResTy; 1910 if (cast<DeclContext>(currentDecl)->isDependentContext()) { 1911 ResTy = Context.DependentTy; 1912 } else { 1913 unsigned Length = PredefinedExpr::ComputeName(IT, currentDecl).length(); 1914 1915 llvm::APInt LengthI(32, Length + 1); 1916 ResTy = Context.CharTy.withConst(); 1917 ResTy = Context.getConstantArrayType(ResTy, LengthI, ArrayType::Normal, 0); 1918 } 1919 return Owned(new (Context) PredefinedExpr(Loc, ResTy, IT)); 1920} 1921 1922ExprResult Sema::ActOnCharacterConstant(const Token &Tok) { 1923 llvm::SmallString<16> CharBuffer; 1924 bool Invalid = false; 1925 llvm::StringRef ThisTok = PP.getSpelling(Tok, CharBuffer, &Invalid); 1926 if (Invalid) 1927 return ExprError(); 1928 1929 CharLiteralParser Literal(ThisTok.begin(), ThisTok.end(), Tok.getLocation(), 1930 PP); 1931 if (Literal.hadError()) 1932 return ExprError(); 1933 1934 QualType Ty; 1935 if (!getLangOptions().CPlusPlus) 1936 Ty = Context.IntTy; // 'x' and L'x' -> int in C. 1937 else if (Literal.isWide()) 1938 Ty = Context.WCharTy; // L'x' -> wchar_t in C++. 1939 else if (Literal.isMultiChar()) 1940 Ty = Context.IntTy; // 'wxyz' -> int in C++. 1941 else 1942 Ty = Context.CharTy; // 'x' -> char in C++ 1943 1944 return Owned(new (Context) CharacterLiteral(Literal.getValue(), 1945 Literal.isWide(), 1946 Ty, Tok.getLocation())); 1947} 1948 1949ExprResult Sema::ActOnNumericConstant(const Token &Tok) { 1950 // Fast path for a single digit (which is quite common). A single digit 1951 // cannot have a trigraph, escaped newline, radix prefix, or type suffix. 1952 if (Tok.getLength() == 1) { 1953 const char Val = PP.getSpellingOfSingleCharacterNumericConstant(Tok); 1954 unsigned IntSize = Context.Target.getIntWidth(); 1955 return Owned(IntegerLiteral::Create(Context, llvm::APInt(IntSize, Val-'0'), 1956 Context.IntTy, Tok.getLocation())); 1957 } 1958 1959 llvm::SmallString<512> IntegerBuffer; 1960 // Add padding so that NumericLiteralParser can overread by one character. 1961 IntegerBuffer.resize(Tok.getLength()+1); 1962 const char *ThisTokBegin = &IntegerBuffer[0]; 1963 1964 // Get the spelling of the token, which eliminates trigraphs, etc. 1965 bool Invalid = false; 1966 unsigned ActualLength = PP.getSpelling(Tok, ThisTokBegin, &Invalid); 1967 if (Invalid) 1968 return ExprError(); 1969 1970 NumericLiteralParser Literal(ThisTokBegin, ThisTokBegin+ActualLength, 1971 Tok.getLocation(), PP); 1972 if (Literal.hadError) 1973 return ExprError(); 1974 1975 Expr *Res; 1976 1977 if (Literal.isFloatingLiteral()) { 1978 QualType Ty; 1979 if (Literal.isFloat) 1980 Ty = Context.FloatTy; 1981 else if (!Literal.isLong) 1982 Ty = Context.DoubleTy; 1983 else 1984 Ty = Context.LongDoubleTy; 1985 1986 const llvm::fltSemantics &Format = Context.getFloatTypeSemantics(Ty); 1987 1988 using llvm::APFloat; 1989 APFloat Val(Format); 1990 1991 APFloat::opStatus result = Literal.GetFloatValue(Val); 1992 1993 // Overflow is always an error, but underflow is only an error if 1994 // we underflowed to zero (APFloat reports denormals as underflow). 1995 if ((result & APFloat::opOverflow) || 1996 ((result & APFloat::opUnderflow) && Val.isZero())) { 1997 unsigned diagnostic; 1998 llvm::SmallString<20> buffer; 1999 if (result & APFloat::opOverflow) { 2000 diagnostic = diag::warn_float_overflow; 2001 APFloat::getLargest(Format).toString(buffer); 2002 } else { 2003 diagnostic = diag::warn_float_underflow; 2004 APFloat::getSmallest(Format).toString(buffer); 2005 } 2006 2007 Diag(Tok.getLocation(), diagnostic) 2008 << Ty 2009 << llvm::StringRef(buffer.data(), buffer.size()); 2010 } 2011 2012 bool isExact = (result == APFloat::opOK); 2013 Res = FloatingLiteral::Create(Context, Val, isExact, Ty, Tok.getLocation()); 2014 2015 } else if (!Literal.isIntegerLiteral()) { 2016 return ExprError(); 2017 } else { 2018 QualType Ty; 2019 2020 // long long is a C99 feature. 2021 if (!getLangOptions().C99 && !getLangOptions().CPlusPlus0x && 2022 Literal.isLongLong) 2023 Diag(Tok.getLocation(), diag::ext_longlong); 2024 2025 // Get the value in the widest-possible width. 2026 llvm::APInt ResultVal(Context.Target.getIntMaxTWidth(), 0); 2027 2028 if (Literal.GetIntegerValue(ResultVal)) { 2029 // If this value didn't fit into uintmax_t, warn and force to ull. 2030 Diag(Tok.getLocation(), diag::warn_integer_too_large); 2031 Ty = Context.UnsignedLongLongTy; 2032 assert(Context.getTypeSize(Ty) == ResultVal.getBitWidth() && 2033 "long long is not intmax_t?"); 2034 } else { 2035 // If this value fits into a ULL, try to figure out what else it fits into 2036 // according to the rules of C99 6.4.4.1p5. 2037 2038 // Octal, Hexadecimal, and integers with a U suffix are allowed to 2039 // be an unsigned int. 2040 bool AllowUnsigned = Literal.isUnsigned || Literal.getRadix() != 10; 2041 2042 // Check from smallest to largest, picking the smallest type we can. 2043 unsigned Width = 0; 2044 if (!Literal.isLong && !Literal.isLongLong) { 2045 // Are int/unsigned possibilities? 2046 unsigned IntSize = Context.Target.getIntWidth(); 2047 2048 // Does it fit in a unsigned int? 2049 if (ResultVal.isIntN(IntSize)) { 2050 // Does it fit in a signed int? 2051 if (!Literal.isUnsigned && ResultVal[IntSize-1] == 0) 2052 Ty = Context.IntTy; 2053 else if (AllowUnsigned) 2054 Ty = Context.UnsignedIntTy; 2055 Width = IntSize; 2056 } 2057 } 2058 2059 // Are long/unsigned long possibilities? 2060 if (Ty.isNull() && !Literal.isLongLong) { 2061 unsigned LongSize = Context.Target.getLongWidth(); 2062 2063 // Does it fit in a unsigned long? 2064 if (ResultVal.isIntN(LongSize)) { 2065 // Does it fit in a signed long? 2066 if (!Literal.isUnsigned && ResultVal[LongSize-1] == 0) 2067 Ty = Context.LongTy; 2068 else if (AllowUnsigned) 2069 Ty = Context.UnsignedLongTy; 2070 Width = LongSize; 2071 } 2072 } 2073 2074 // Finally, check long long if needed. 2075 if (Ty.isNull()) { 2076 unsigned LongLongSize = Context.Target.getLongLongWidth(); 2077 2078 // Does it fit in a unsigned long long? 2079 if (ResultVal.isIntN(LongLongSize)) { 2080 // Does it fit in a signed long long? 2081 if (!Literal.isUnsigned && ResultVal[LongLongSize-1] == 0) 2082 Ty = Context.LongLongTy; 2083 else if (AllowUnsigned) 2084 Ty = Context.UnsignedLongLongTy; 2085 Width = LongLongSize; 2086 } 2087 } 2088 2089 // If we still couldn't decide a type, we probably have something that 2090 // does not fit in a signed long long, but has no U suffix. 2091 if (Ty.isNull()) { 2092 Diag(Tok.getLocation(), diag::warn_integer_too_large_for_signed); 2093 Ty = Context.UnsignedLongLongTy; 2094 Width = Context.Target.getLongLongWidth(); 2095 } 2096 2097 if (ResultVal.getBitWidth() != Width) 2098 ResultVal.trunc(Width); 2099 } 2100 Res = IntegerLiteral::Create(Context, ResultVal, Ty, Tok.getLocation()); 2101 } 2102 2103 // If this is an imaginary literal, create the ImaginaryLiteral wrapper. 2104 if (Literal.isImaginary) 2105 Res = new (Context) ImaginaryLiteral(Res, 2106 Context.getComplexType(Res->getType())); 2107 2108 return Owned(Res); 2109} 2110 2111ExprResult Sema::ActOnParenExpr(SourceLocation L, 2112 SourceLocation R, Expr *E) { 2113 assert((E != 0) && "ActOnParenExpr() missing expr"); 2114 return Owned(new (Context) ParenExpr(L, R, E)); 2115} 2116 2117/// The UsualUnaryConversions() function is *not* called by this routine. 2118/// See C99 6.3.2.1p[2-4] for more details. 2119bool Sema::CheckSizeOfAlignOfOperand(QualType exprType, 2120 SourceLocation OpLoc, 2121 const SourceRange &ExprRange, 2122 bool isSizeof) { 2123 if (exprType->isDependentType()) 2124 return false; 2125 2126 // C++ [expr.sizeof]p2: "When applied to a reference or a reference type, 2127 // the result is the size of the referenced type." 2128 // C++ [expr.alignof]p3: "When alignof is applied to a reference type, the 2129 // result shall be the alignment of the referenced type." 2130 if (const ReferenceType *Ref = exprType->getAs<ReferenceType>()) 2131 exprType = Ref->getPointeeType(); 2132 2133 // C99 6.5.3.4p1: 2134 if (exprType->isFunctionType()) { 2135 // alignof(function) is allowed as an extension. 2136 if (isSizeof) 2137 Diag(OpLoc, diag::ext_sizeof_function_type) << ExprRange; 2138 return false; 2139 } 2140 2141 // Allow sizeof(void)/alignof(void) as an extension. 2142 if (exprType->isVoidType()) { 2143 Diag(OpLoc, diag::ext_sizeof_void_type) 2144 << (isSizeof ? "sizeof" : "__alignof") << ExprRange; 2145 return false; 2146 } 2147 2148 if (RequireCompleteType(OpLoc, exprType, 2149 PDiag(diag::err_sizeof_alignof_incomplete_type) 2150 << int(!isSizeof) << ExprRange)) 2151 return true; 2152 2153 // Reject sizeof(interface) and sizeof(interface<proto>) in 64-bit mode. 2154 if (LangOpts.ObjCNonFragileABI && exprType->isObjCObjectType()) { 2155 Diag(OpLoc, diag::err_sizeof_nonfragile_interface) 2156 << exprType << isSizeof << ExprRange; 2157 return true; 2158 } 2159 2160 if (Context.hasSameUnqualifiedType(exprType, Context.OverloadTy)) { 2161 Diag(OpLoc, diag::err_sizeof_alignof_overloaded_function_type) 2162 << !isSizeof << ExprRange; 2163 return true; 2164 } 2165 2166 return false; 2167} 2168 2169bool Sema::CheckAlignOfExpr(Expr *E, SourceLocation OpLoc, 2170 const SourceRange &ExprRange) { 2171 E = E->IgnoreParens(); 2172 2173 // alignof decl is always ok. 2174 if (isa<DeclRefExpr>(E)) 2175 return false; 2176 2177 // Cannot know anything else if the expression is dependent. 2178 if (E->isTypeDependent()) 2179 return false; 2180 2181 if (E->getBitField()) { 2182 Diag(OpLoc, diag::err_sizeof_alignof_bitfield) << 1 << ExprRange; 2183 return true; 2184 } 2185 2186 // Alignment of a field access is always okay, so long as it isn't a 2187 // bit-field. 2188 if (MemberExpr *ME = dyn_cast<MemberExpr>(E)) 2189 if (isa<FieldDecl>(ME->getMemberDecl())) 2190 return false; 2191 2192 return CheckSizeOfAlignOfOperand(E->getType(), OpLoc, ExprRange, false); 2193} 2194 2195/// \brief Build a sizeof or alignof expression given a type operand. 2196ExprResult 2197Sema::CreateSizeOfAlignOfExpr(TypeSourceInfo *TInfo, 2198 SourceLocation OpLoc, 2199 bool isSizeOf, SourceRange R) { 2200 if (!TInfo) 2201 return ExprError(); 2202 2203 QualType T = TInfo->getType(); 2204 2205 if (!T->isDependentType() && 2206 CheckSizeOfAlignOfOperand(T, OpLoc, R, isSizeOf)) 2207 return ExprError(); 2208 2209 // C99 6.5.3.4p4: the type (an unsigned integer type) is size_t. 2210 return Owned(new (Context) SizeOfAlignOfExpr(isSizeOf, TInfo, 2211 Context.getSizeType(), OpLoc, 2212 R.getEnd())); 2213} 2214 2215/// \brief Build a sizeof or alignof expression given an expression 2216/// operand. 2217ExprResult 2218Sema::CreateSizeOfAlignOfExpr(Expr *E, SourceLocation OpLoc, 2219 bool isSizeOf, SourceRange R) { 2220 // Verify that the operand is valid. 2221 bool isInvalid = false; 2222 if (E->isTypeDependent()) { 2223 // Delay type-checking for type-dependent expressions. 2224 } else if (!isSizeOf) { 2225 isInvalid = CheckAlignOfExpr(E, OpLoc, R); 2226 } else if (E->getBitField()) { // C99 6.5.3.4p1. 2227 Diag(OpLoc, diag::err_sizeof_alignof_bitfield) << 0; 2228 isInvalid = true; 2229 } else { 2230 isInvalid = CheckSizeOfAlignOfOperand(E->getType(), OpLoc, R, true); 2231 } 2232 2233 if (isInvalid) 2234 return ExprError(); 2235 2236 // C99 6.5.3.4p4: the type (an unsigned integer type) is size_t. 2237 return Owned(new (Context) SizeOfAlignOfExpr(isSizeOf, E, 2238 Context.getSizeType(), OpLoc, 2239 R.getEnd())); 2240} 2241 2242/// ActOnSizeOfAlignOfExpr - Handle @c sizeof(type) and @c sizeof @c expr and 2243/// the same for @c alignof and @c __alignof 2244/// Note that the ArgRange is invalid if isType is false. 2245ExprResult 2246Sema::ActOnSizeOfAlignOfExpr(SourceLocation OpLoc, bool isSizeof, bool isType, 2247 void *TyOrEx, const SourceRange &ArgRange) { 2248 // If error parsing type, ignore. 2249 if (TyOrEx == 0) return ExprError(); 2250 2251 if (isType) { 2252 TypeSourceInfo *TInfo; 2253 (void) GetTypeFromParser(ParsedType::getFromOpaquePtr(TyOrEx), &TInfo); 2254 return CreateSizeOfAlignOfExpr(TInfo, OpLoc, isSizeof, ArgRange); 2255 } 2256 2257 Expr *ArgEx = (Expr *)TyOrEx; 2258 ExprResult Result 2259 = CreateSizeOfAlignOfExpr(ArgEx, OpLoc, isSizeof, ArgEx->getSourceRange()); 2260 2261 return move(Result); 2262} 2263 2264QualType Sema::CheckRealImagOperand(Expr *&V, SourceLocation Loc, bool isReal) { 2265 if (V->isTypeDependent()) 2266 return Context.DependentTy; 2267 2268 // These operators return the element type of a complex type. 2269 if (const ComplexType *CT = V->getType()->getAs<ComplexType>()) 2270 return CT->getElementType(); 2271 2272 // Otherwise they pass through real integer and floating point types here. 2273 if (V->getType()->isArithmeticType()) 2274 return V->getType(); 2275 2276 // Reject anything else. 2277 Diag(Loc, diag::err_realimag_invalid_type) << V->getType() 2278 << (isReal ? "__real" : "__imag"); 2279 return QualType(); 2280} 2281 2282 2283 2284ExprResult 2285Sema::ActOnPostfixUnaryOp(Scope *S, SourceLocation OpLoc, 2286 tok::TokenKind Kind, Expr *Input) { 2287 UnaryOperatorKind Opc; 2288 switch (Kind) { 2289 default: assert(0 && "Unknown unary op!"); 2290 case tok::plusplus: Opc = UO_PostInc; break; 2291 case tok::minusminus: Opc = UO_PostDec; break; 2292 } 2293 2294 return BuildUnaryOp(S, OpLoc, Opc, Input); 2295} 2296 2297ExprResult 2298Sema::ActOnArraySubscriptExpr(Scope *S, Expr *Base, SourceLocation LLoc, 2299 Expr *Idx, SourceLocation RLoc) { 2300 // Since this might be a postfix expression, get rid of ParenListExprs. 2301 ExprResult Result = MaybeConvertParenListExprToParenExpr(S, Base); 2302 if (Result.isInvalid()) return ExprError(); 2303 Base = Result.take(); 2304 2305 Expr *LHSExp = Base, *RHSExp = Idx; 2306 2307 if (getLangOptions().CPlusPlus && 2308 (LHSExp->isTypeDependent() || RHSExp->isTypeDependent())) { 2309 return Owned(new (Context) ArraySubscriptExpr(LHSExp, RHSExp, 2310 Context.DependentTy, RLoc)); 2311 } 2312 2313 if (getLangOptions().CPlusPlus && 2314 (LHSExp->getType()->isRecordType() || 2315 LHSExp->getType()->isEnumeralType() || 2316 RHSExp->getType()->isRecordType() || 2317 RHSExp->getType()->isEnumeralType())) { 2318 return CreateOverloadedArraySubscriptExpr(LLoc, RLoc, Base, Idx); 2319 } 2320 2321 return CreateBuiltinArraySubscriptExpr(Base, LLoc, Idx, RLoc); 2322} 2323 2324 2325ExprResult 2326Sema::CreateBuiltinArraySubscriptExpr(Expr *Base, SourceLocation LLoc, 2327 Expr *Idx, SourceLocation RLoc) { 2328 Expr *LHSExp = Base; 2329 Expr *RHSExp = Idx; 2330 2331 // Perform default conversions. 2332 if (!LHSExp->getType()->getAs<VectorType>()) 2333 DefaultFunctionArrayLvalueConversion(LHSExp); 2334 DefaultFunctionArrayLvalueConversion(RHSExp); 2335 2336 QualType LHSTy = LHSExp->getType(), RHSTy = RHSExp->getType(); 2337 2338 // C99 6.5.2.1p2: the expression e1[e2] is by definition precisely equivalent 2339 // to the expression *((e1)+(e2)). This means the array "Base" may actually be 2340 // in the subscript position. As a result, we need to derive the array base 2341 // and index from the expression types. 2342 Expr *BaseExpr, *IndexExpr; 2343 QualType ResultType; 2344 if (LHSTy->isDependentType() || RHSTy->isDependentType()) { 2345 BaseExpr = LHSExp; 2346 IndexExpr = RHSExp; 2347 ResultType = Context.DependentTy; 2348 } else if (const PointerType *PTy = LHSTy->getAs<PointerType>()) { 2349 BaseExpr = LHSExp; 2350 IndexExpr = RHSExp; 2351 ResultType = PTy->getPointeeType(); 2352 } else if (const PointerType *PTy = RHSTy->getAs<PointerType>()) { 2353 // Handle the uncommon case of "123[Ptr]". 2354 BaseExpr = RHSExp; 2355 IndexExpr = LHSExp; 2356 ResultType = PTy->getPointeeType(); 2357 } else if (const ObjCObjectPointerType *PTy = 2358 LHSTy->getAs<ObjCObjectPointerType>()) { 2359 BaseExpr = LHSExp; 2360 IndexExpr = RHSExp; 2361 ResultType = PTy->getPointeeType(); 2362 } else if (const ObjCObjectPointerType *PTy = 2363 RHSTy->getAs<ObjCObjectPointerType>()) { 2364 // Handle the uncommon case of "123[Ptr]". 2365 BaseExpr = RHSExp; 2366 IndexExpr = LHSExp; 2367 ResultType = PTy->getPointeeType(); 2368 } else if (const VectorType *VTy = LHSTy->getAs<VectorType>()) { 2369 BaseExpr = LHSExp; // vectors: V[123] 2370 IndexExpr = RHSExp; 2371 2372 // FIXME: need to deal with const... 2373 ResultType = VTy->getElementType(); 2374 } else if (LHSTy->isArrayType()) { 2375 // If we see an array that wasn't promoted by 2376 // DefaultFunctionArrayLvalueConversion, it must be an array that 2377 // wasn't promoted because of the C90 rule that doesn't 2378 // allow promoting non-lvalue arrays. Warn, then 2379 // force the promotion here. 2380 Diag(LHSExp->getLocStart(), diag::ext_subscript_non_lvalue) << 2381 LHSExp->getSourceRange(); 2382 ImpCastExprToType(LHSExp, Context.getArrayDecayedType(LHSTy), 2383 CK_ArrayToPointerDecay); 2384 LHSTy = LHSExp->getType(); 2385 2386 BaseExpr = LHSExp; 2387 IndexExpr = RHSExp; 2388 ResultType = LHSTy->getAs<PointerType>()->getPointeeType(); 2389 } else if (RHSTy->isArrayType()) { 2390 // Same as previous, except for 123[f().a] case 2391 Diag(RHSExp->getLocStart(), diag::ext_subscript_non_lvalue) << 2392 RHSExp->getSourceRange(); 2393 ImpCastExprToType(RHSExp, Context.getArrayDecayedType(RHSTy), 2394 CK_ArrayToPointerDecay); 2395 RHSTy = RHSExp->getType(); 2396 2397 BaseExpr = RHSExp; 2398 IndexExpr = LHSExp; 2399 ResultType = RHSTy->getAs<PointerType>()->getPointeeType(); 2400 } else { 2401 return ExprError(Diag(LLoc, diag::err_typecheck_subscript_value) 2402 << LHSExp->getSourceRange() << RHSExp->getSourceRange()); 2403 } 2404 // C99 6.5.2.1p1 2405 if (!IndexExpr->getType()->isIntegerType() && !IndexExpr->isTypeDependent()) 2406 return ExprError(Diag(LLoc, diag::err_typecheck_subscript_not_integer) 2407 << IndexExpr->getSourceRange()); 2408 2409 if ((IndexExpr->getType()->isSpecificBuiltinType(BuiltinType::Char_S) || 2410 IndexExpr->getType()->isSpecificBuiltinType(BuiltinType::Char_U)) 2411 && !IndexExpr->isTypeDependent()) 2412 Diag(LLoc, diag::warn_subscript_is_char) << IndexExpr->getSourceRange(); 2413 2414 // C99 6.5.2.1p1: "shall have type "pointer to *object* type". Similarly, 2415 // C++ [expr.sub]p1: The type "T" shall be a completely-defined object 2416 // type. Note that Functions are not objects, and that (in C99 parlance) 2417 // incomplete types are not object types. 2418 if (ResultType->isFunctionType()) { 2419 Diag(BaseExpr->getLocStart(), diag::err_subscript_function_type) 2420 << ResultType << BaseExpr->getSourceRange(); 2421 return ExprError(); 2422 } 2423 2424 if (ResultType->isVoidType() && !getLangOptions().CPlusPlus) { 2425 // GNU extension: subscripting on pointer to void 2426 Diag(LLoc, diag::ext_gnu_void_ptr) 2427 << BaseExpr->getSourceRange(); 2428 } else if (!ResultType->isDependentType() && 2429 RequireCompleteType(LLoc, ResultType, 2430 PDiag(diag::err_subscript_incomplete_type) 2431 << BaseExpr->getSourceRange())) 2432 return ExprError(); 2433 2434 // Diagnose bad cases where we step over interface counts. 2435 if (ResultType->isObjCObjectType() && LangOpts.ObjCNonFragileABI) { 2436 Diag(LLoc, diag::err_subscript_nonfragile_interface) 2437 << ResultType << BaseExpr->getSourceRange(); 2438 return ExprError(); 2439 } 2440 2441 return Owned(new (Context) ArraySubscriptExpr(LHSExp, RHSExp, 2442 ResultType, RLoc)); 2443} 2444 2445QualType Sema:: 2446CheckExtVectorComponent(QualType baseType, SourceLocation OpLoc, 2447 const IdentifierInfo *CompName, 2448 SourceLocation CompLoc) { 2449 // FIXME: Share logic with ExtVectorElementExpr::containsDuplicateElements, 2450 // see FIXME there. 2451 // 2452 // FIXME: This logic can be greatly simplified by splitting it along 2453 // halving/not halving and reworking the component checking. 2454 const ExtVectorType *vecType = baseType->getAs<ExtVectorType>(); 2455 2456 // The vector accessor can't exceed the number of elements. 2457 const char *compStr = CompName->getNameStart(); 2458 2459 // This flag determines whether or not the component is one of the four 2460 // special names that indicate a subset of exactly half the elements are 2461 // to be selected. 2462 bool HalvingSwizzle = false; 2463 2464 // This flag determines whether or not CompName has an 's' char prefix, 2465 // indicating that it is a string of hex values to be used as vector indices. 2466 bool HexSwizzle = *compStr == 's' || *compStr == 'S'; 2467 2468 // Check that we've found one of the special components, or that the component 2469 // names must come from the same set. 2470 if (!strcmp(compStr, "hi") || !strcmp(compStr, "lo") || 2471 !strcmp(compStr, "even") || !strcmp(compStr, "odd")) { 2472 HalvingSwizzle = true; 2473 } else if (vecType->getPointAccessorIdx(*compStr) != -1) { 2474 do 2475 compStr++; 2476 while (*compStr && vecType->getPointAccessorIdx(*compStr) != -1); 2477 } else if (HexSwizzle || vecType->getNumericAccessorIdx(*compStr) != -1) { 2478 do 2479 compStr++; 2480 while (*compStr && vecType->getNumericAccessorIdx(*compStr) != -1); 2481 } 2482 2483 if (!HalvingSwizzle && *compStr) { 2484 // We didn't get to the end of the string. This means the component names 2485 // didn't come from the same set *or* we encountered an illegal name. 2486 Diag(OpLoc, diag::err_ext_vector_component_name_illegal) 2487 << llvm::StringRef(compStr, 1) << SourceRange(CompLoc); 2488 return QualType(); 2489 } 2490 2491 // Ensure no component accessor exceeds the width of the vector type it 2492 // operates on. 2493 if (!HalvingSwizzle) { 2494 compStr = CompName->getNameStart(); 2495 2496 if (HexSwizzle) 2497 compStr++; 2498 2499 while (*compStr) { 2500 if (!vecType->isAccessorWithinNumElements(*compStr++)) { 2501 Diag(OpLoc, diag::err_ext_vector_component_exceeds_length) 2502 << baseType << SourceRange(CompLoc); 2503 return QualType(); 2504 } 2505 } 2506 } 2507 2508 // The component accessor looks fine - now we need to compute the actual type. 2509 // The vector type is implied by the component accessor. For example, 2510 // vec4.b is a float, vec4.xy is a vec2, vec4.rgb is a vec3, etc. 2511 // vec4.s0 is a float, vec4.s23 is a vec3, etc. 2512 // vec4.hi, vec4.lo, vec4.e, and vec4.o all return vec2. 2513 unsigned CompSize = HalvingSwizzle ? (vecType->getNumElements() + 1) / 2 2514 : CompName->getLength(); 2515 if (HexSwizzle) 2516 CompSize--; 2517 2518 if (CompSize == 1) 2519 return vecType->getElementType(); 2520 2521 QualType VT = Context.getExtVectorType(vecType->getElementType(), CompSize); 2522 // Now look up the TypeDefDecl from the vector type. Without this, 2523 // diagostics look bad. We want extended vector types to appear built-in. 2524 for (unsigned i = 0, E = ExtVectorDecls.size(); i != E; ++i) { 2525 if (ExtVectorDecls[i]->getUnderlyingType() == VT) 2526 return Context.getTypedefType(ExtVectorDecls[i]); 2527 } 2528 return VT; // should never get here (a typedef type should always be found). 2529} 2530 2531static Decl *FindGetterNameDeclFromProtocolList(const ObjCProtocolDecl*PDecl, 2532 IdentifierInfo *Member, 2533 const Selector &Sel, 2534 ASTContext &Context) { 2535 2536 if (ObjCPropertyDecl *PD = PDecl->FindPropertyDeclaration(Member)) 2537 return PD; 2538 if (ObjCMethodDecl *OMD = PDecl->getInstanceMethod(Sel)) 2539 return OMD; 2540 2541 for (ObjCProtocolDecl::protocol_iterator I = PDecl->protocol_begin(), 2542 E = PDecl->protocol_end(); I != E; ++I) { 2543 if (Decl *D = FindGetterNameDeclFromProtocolList(*I, Member, Sel, 2544 Context)) 2545 return D; 2546 } 2547 return 0; 2548} 2549 2550static Decl *FindGetterNameDecl(const ObjCObjectPointerType *QIdTy, 2551 IdentifierInfo *Member, 2552 const Selector &Sel, 2553 ASTContext &Context) { 2554 // Check protocols on qualified interfaces. 2555 Decl *GDecl = 0; 2556 for (ObjCObjectPointerType::qual_iterator I = QIdTy->qual_begin(), 2557 E = QIdTy->qual_end(); I != E; ++I) { 2558 if (ObjCPropertyDecl *PD = (*I)->FindPropertyDeclaration(Member)) { 2559 GDecl = PD; 2560 break; 2561 } 2562 // Also must look for a getter name which uses property syntax. 2563 if (ObjCMethodDecl *OMD = (*I)->getInstanceMethod(Sel)) { 2564 GDecl = OMD; 2565 break; 2566 } 2567 } 2568 if (!GDecl) { 2569 for (ObjCObjectPointerType::qual_iterator I = QIdTy->qual_begin(), 2570 E = QIdTy->qual_end(); I != E; ++I) { 2571 // Search in the protocol-qualifier list of current protocol. 2572 GDecl = FindGetterNameDeclFromProtocolList(*I, Member, Sel, Context); 2573 if (GDecl) 2574 return GDecl; 2575 } 2576 } 2577 return GDecl; 2578} 2579 2580ExprResult 2581Sema::ActOnDependentMemberExpr(Expr *BaseExpr, QualType BaseType, 2582 bool IsArrow, SourceLocation OpLoc, 2583 const CXXScopeSpec &SS, 2584 NamedDecl *FirstQualifierInScope, 2585 const DeclarationNameInfo &NameInfo, 2586 const TemplateArgumentListInfo *TemplateArgs) { 2587 // Even in dependent contexts, try to diagnose base expressions with 2588 // obviously wrong types, e.g.: 2589 // 2590 // T* t; 2591 // t.f; 2592 // 2593 // In Obj-C++, however, the above expression is valid, since it could be 2594 // accessing the 'f' property if T is an Obj-C interface. The extra check 2595 // allows this, while still reporting an error if T is a struct pointer. 2596 if (!IsArrow) { 2597 const PointerType *PT = BaseType->getAs<PointerType>(); 2598 if (PT && (!getLangOptions().ObjC1 || 2599 PT->getPointeeType()->isRecordType())) { 2600 assert(BaseExpr && "cannot happen with implicit member accesses"); 2601 Diag(NameInfo.getLoc(), diag::err_typecheck_member_reference_struct_union) 2602 << BaseType << BaseExpr->getSourceRange(); 2603 return ExprError(); 2604 } 2605 } 2606 2607 assert(BaseType->isDependentType() || 2608 NameInfo.getName().isDependentName() || 2609 isDependentScopeSpecifier(SS)); 2610 2611 // Get the type being accessed in BaseType. If this is an arrow, the BaseExpr 2612 // must have pointer type, and the accessed type is the pointee. 2613 return Owned(CXXDependentScopeMemberExpr::Create(Context, BaseExpr, BaseType, 2614 IsArrow, OpLoc, 2615 SS.getScopeRep(), 2616 SS.getRange(), 2617 FirstQualifierInScope, 2618 NameInfo, TemplateArgs)); 2619} 2620 2621/// We know that the given qualified member reference points only to 2622/// declarations which do not belong to the static type of the base 2623/// expression. Diagnose the problem. 2624static void DiagnoseQualifiedMemberReference(Sema &SemaRef, 2625 Expr *BaseExpr, 2626 QualType BaseType, 2627 const CXXScopeSpec &SS, 2628 const LookupResult &R) { 2629 // If this is an implicit member access, use a different set of 2630 // diagnostics. 2631 if (!BaseExpr) 2632 return DiagnoseInstanceReference(SemaRef, SS, R); 2633 2634 SemaRef.Diag(R.getNameLoc(), diag::err_qualified_member_of_unrelated) 2635 << SS.getRange() << R.getRepresentativeDecl() << BaseType; 2636} 2637 2638// Check whether the declarations we found through a nested-name 2639// specifier in a member expression are actually members of the base 2640// type. The restriction here is: 2641// 2642// C++ [expr.ref]p2: 2643// ... In these cases, the id-expression shall name a 2644// member of the class or of one of its base classes. 2645// 2646// So it's perfectly legitimate for the nested-name specifier to name 2647// an unrelated class, and for us to find an overload set including 2648// decls from classes which are not superclasses, as long as the decl 2649// we actually pick through overload resolution is from a superclass. 2650bool Sema::CheckQualifiedMemberReference(Expr *BaseExpr, 2651 QualType BaseType, 2652 const CXXScopeSpec &SS, 2653 const LookupResult &R) { 2654 const RecordType *BaseRT = BaseType->getAs<RecordType>(); 2655 if (!BaseRT) { 2656 // We can't check this yet because the base type is still 2657 // dependent. 2658 assert(BaseType->isDependentType()); 2659 return false; 2660 } 2661 CXXRecordDecl *BaseRecord = cast<CXXRecordDecl>(BaseRT->getDecl()); 2662 2663 for (LookupResult::iterator I = R.begin(), E = R.end(); I != E; ++I) { 2664 // If this is an implicit member reference and we find a 2665 // non-instance member, it's not an error. 2666 if (!BaseExpr && !(*I)->isCXXInstanceMember()) 2667 return false; 2668 2669 // Note that we use the DC of the decl, not the underlying decl. 2670 DeclContext *DC = (*I)->getDeclContext(); 2671 while (DC->isTransparentContext()) 2672 DC = DC->getParent(); 2673 2674 if (!DC->isRecord()) 2675 continue; 2676 2677 llvm::SmallPtrSet<CXXRecordDecl*,4> MemberRecord; 2678 MemberRecord.insert(cast<CXXRecordDecl>(DC)->getCanonicalDecl()); 2679 2680 if (!IsProvablyNotDerivedFrom(*this, BaseRecord, MemberRecord)) 2681 return false; 2682 } 2683 2684 DiagnoseQualifiedMemberReference(*this, BaseExpr, BaseType, SS, R); 2685 return true; 2686} 2687 2688static bool 2689LookupMemberExprInRecord(Sema &SemaRef, LookupResult &R, 2690 SourceRange BaseRange, const RecordType *RTy, 2691 SourceLocation OpLoc, CXXScopeSpec &SS, 2692 bool HasTemplateArgs) { 2693 RecordDecl *RDecl = RTy->getDecl(); 2694 if (SemaRef.RequireCompleteType(OpLoc, QualType(RTy, 0), 2695 SemaRef.PDiag(diag::err_typecheck_incomplete_tag) 2696 << BaseRange)) 2697 return true; 2698 2699 if (HasTemplateArgs) { 2700 // LookupTemplateName doesn't expect these both to exist simultaneously. 2701 QualType ObjectType = SS.isSet() ? QualType() : QualType(RTy, 0); 2702 2703 bool MOUS; 2704 SemaRef.LookupTemplateName(R, 0, SS, ObjectType, false, MOUS); 2705 return false; 2706 } 2707 2708 DeclContext *DC = RDecl; 2709 if (SS.isSet()) { 2710 // If the member name was a qualified-id, look into the 2711 // nested-name-specifier. 2712 DC = SemaRef.computeDeclContext(SS, false); 2713 2714 if (SemaRef.RequireCompleteDeclContext(SS, DC)) { 2715 SemaRef.Diag(SS.getRange().getEnd(), diag::err_typecheck_incomplete_tag) 2716 << SS.getRange() << DC; 2717 return true; 2718 } 2719 2720 assert(DC && "Cannot handle non-computable dependent contexts in lookup"); 2721 2722 if (!isa<TypeDecl>(DC)) { 2723 SemaRef.Diag(R.getNameLoc(), diag::err_qualified_member_nonclass) 2724 << DC << SS.getRange(); 2725 return true; 2726 } 2727 } 2728 2729 // The record definition is complete, now look up the member. 2730 SemaRef.LookupQualifiedName(R, DC); 2731 2732 if (!R.empty()) 2733 return false; 2734 2735 // We didn't find anything with the given name, so try to correct 2736 // for typos. 2737 DeclarationName Name = R.getLookupName(); 2738 if (SemaRef.CorrectTypo(R, 0, &SS, DC, false, Sema::CTC_MemberLookup) && 2739 !R.empty() && 2740 (isa<ValueDecl>(*R.begin()) || isa<FunctionTemplateDecl>(*R.begin()))) { 2741 SemaRef.Diag(R.getNameLoc(), diag::err_no_member_suggest) 2742 << Name << DC << R.getLookupName() << SS.getRange() 2743 << FixItHint::CreateReplacement(R.getNameLoc(), 2744 R.getLookupName().getAsString()); 2745 if (NamedDecl *ND = R.getAsSingle<NamedDecl>()) 2746 SemaRef.Diag(ND->getLocation(), diag::note_previous_decl) 2747 << ND->getDeclName(); 2748 return false; 2749 } else { 2750 R.clear(); 2751 R.setLookupName(Name); 2752 } 2753 2754 return false; 2755} 2756 2757ExprResult 2758Sema::BuildMemberReferenceExpr(Expr *Base, QualType BaseType, 2759 SourceLocation OpLoc, bool IsArrow, 2760 CXXScopeSpec &SS, 2761 NamedDecl *FirstQualifierInScope, 2762 const DeclarationNameInfo &NameInfo, 2763 const TemplateArgumentListInfo *TemplateArgs) { 2764 if (BaseType->isDependentType() || 2765 (SS.isSet() && isDependentScopeSpecifier(SS))) 2766 return ActOnDependentMemberExpr(Base, BaseType, 2767 IsArrow, OpLoc, 2768 SS, FirstQualifierInScope, 2769 NameInfo, TemplateArgs); 2770 2771 LookupResult R(*this, NameInfo, LookupMemberName); 2772 2773 // Implicit member accesses. 2774 if (!Base) { 2775 QualType RecordTy = BaseType; 2776 if (IsArrow) RecordTy = RecordTy->getAs<PointerType>()->getPointeeType(); 2777 if (LookupMemberExprInRecord(*this, R, SourceRange(), 2778 RecordTy->getAs<RecordType>(), 2779 OpLoc, SS, TemplateArgs != 0)) 2780 return ExprError(); 2781 2782 // Explicit member accesses. 2783 } else { 2784 ExprResult Result = 2785 LookupMemberExpr(R, Base, IsArrow, OpLoc, 2786 SS, /*ObjCImpDecl*/ 0, TemplateArgs != 0); 2787 2788 if (Result.isInvalid()) { 2789 Owned(Base); 2790 return ExprError(); 2791 } 2792 2793 if (Result.get()) 2794 return move(Result); 2795 2796 // LookupMemberExpr can modify Base, and thus change BaseType 2797 BaseType = Base->getType(); 2798 } 2799 2800 return BuildMemberReferenceExpr(Base, BaseType, 2801 OpLoc, IsArrow, SS, FirstQualifierInScope, 2802 R, TemplateArgs); 2803} 2804 2805ExprResult 2806Sema::BuildMemberReferenceExpr(Expr *BaseExpr, QualType BaseExprType, 2807 SourceLocation OpLoc, bool IsArrow, 2808 const CXXScopeSpec &SS, 2809 NamedDecl *FirstQualifierInScope, 2810 LookupResult &R, 2811 const TemplateArgumentListInfo *TemplateArgs, 2812 bool SuppressQualifierCheck) { 2813 QualType BaseType = BaseExprType; 2814 if (IsArrow) { 2815 assert(BaseType->isPointerType()); 2816 BaseType = BaseType->getAs<PointerType>()->getPointeeType(); 2817 } 2818 R.setBaseObjectType(BaseType); 2819 2820 NestedNameSpecifier *Qualifier = SS.getScopeRep(); 2821 const DeclarationNameInfo &MemberNameInfo = R.getLookupNameInfo(); 2822 DeclarationName MemberName = MemberNameInfo.getName(); 2823 SourceLocation MemberLoc = MemberNameInfo.getLoc(); 2824 2825 if (R.isAmbiguous()) 2826 return ExprError(); 2827 2828 if (R.empty()) { 2829 // Rederive where we looked up. 2830 DeclContext *DC = (SS.isSet() 2831 ? computeDeclContext(SS, false) 2832 : BaseType->getAs<RecordType>()->getDecl()); 2833 2834 Diag(R.getNameLoc(), diag::err_no_member) 2835 << MemberName << DC 2836 << (BaseExpr ? BaseExpr->getSourceRange() : SourceRange()); 2837 return ExprError(); 2838 } 2839 2840 // Diagnose lookups that find only declarations from a non-base 2841 // type. This is possible for either qualified lookups (which may 2842 // have been qualified with an unrelated type) or implicit member 2843 // expressions (which were found with unqualified lookup and thus 2844 // may have come from an enclosing scope). Note that it's okay for 2845 // lookup to find declarations from a non-base type as long as those 2846 // aren't the ones picked by overload resolution. 2847 if ((SS.isSet() || !BaseExpr || 2848 (isa<CXXThisExpr>(BaseExpr) && 2849 cast<CXXThisExpr>(BaseExpr)->isImplicit())) && 2850 !SuppressQualifierCheck && 2851 CheckQualifiedMemberReference(BaseExpr, BaseType, SS, R)) 2852 return ExprError(); 2853 2854 // Construct an unresolved result if we in fact got an unresolved 2855 // result. 2856 if (R.isOverloadedResult() || R.isUnresolvableResult()) { 2857 bool Dependent = 2858 BaseExprType->isDependentType() || 2859 R.isUnresolvableResult() || 2860 OverloadExpr::ComputeDependence(R.begin(), R.end(), TemplateArgs); 2861 2862 // Suppress any lookup-related diagnostics; we'll do these when we 2863 // pick a member. 2864 R.suppressDiagnostics(); 2865 2866 UnresolvedMemberExpr *MemExpr 2867 = UnresolvedMemberExpr::Create(Context, Dependent, 2868 R.isUnresolvableResult(), 2869 BaseExpr, BaseExprType, 2870 IsArrow, OpLoc, 2871 Qualifier, SS.getRange(), 2872 MemberNameInfo, 2873 TemplateArgs, R.begin(), R.end()); 2874 2875 return Owned(MemExpr); 2876 } 2877 2878 assert(R.isSingleResult()); 2879 DeclAccessPair FoundDecl = R.begin().getPair(); 2880 NamedDecl *MemberDecl = R.getFoundDecl(); 2881 2882 // FIXME: diagnose the presence of template arguments now. 2883 2884 // If the decl being referenced had an error, return an error for this 2885 // sub-expr without emitting another error, in order to avoid cascading 2886 // error cases. 2887 if (MemberDecl->isInvalidDecl()) 2888 return ExprError(); 2889 2890 // Handle the implicit-member-access case. 2891 if (!BaseExpr) { 2892 // If this is not an instance member, convert to a non-member access. 2893 if (!MemberDecl->isCXXInstanceMember()) 2894 return BuildDeclarationNameExpr(SS, R.getLookupNameInfo(), MemberDecl); 2895 2896 SourceLocation Loc = R.getNameLoc(); 2897 if (SS.getRange().isValid()) 2898 Loc = SS.getRange().getBegin(); 2899 BaseExpr = new (Context) CXXThisExpr(Loc, BaseExprType,/*isImplicit=*/true); 2900 } 2901 2902 bool ShouldCheckUse = true; 2903 if (CXXMethodDecl *MD = dyn_cast<CXXMethodDecl>(MemberDecl)) { 2904 // Don't diagnose the use of a virtual member function unless it's 2905 // explicitly qualified. 2906 if (MD->isVirtual() && !SS.isSet()) 2907 ShouldCheckUse = false; 2908 } 2909 2910 // Check the use of this member. 2911 if (ShouldCheckUse && DiagnoseUseOfDecl(MemberDecl, MemberLoc)) { 2912 Owned(BaseExpr); 2913 return ExprError(); 2914 } 2915 2916 if (FieldDecl *FD = dyn_cast<FieldDecl>(MemberDecl)) { 2917 // We may have found a field within an anonymous union or struct 2918 // (C++ [class.union]). 2919 if (cast<RecordDecl>(FD->getDeclContext())->isAnonymousStructOrUnion() && 2920 !BaseType->getAs<RecordType>()->getDecl()->isAnonymousStructOrUnion()) 2921 return BuildAnonymousStructUnionMemberReference(MemberLoc, FD, 2922 BaseExpr, OpLoc); 2923 2924 // Figure out the type of the member; see C99 6.5.2.3p3, C++ [expr.ref] 2925 QualType MemberType = FD->getType(); 2926 if (const ReferenceType *Ref = MemberType->getAs<ReferenceType>()) 2927 MemberType = Ref->getPointeeType(); 2928 else { 2929 Qualifiers BaseQuals = BaseType.getQualifiers(); 2930 BaseQuals.removeObjCGCAttr(); 2931 if (FD->isMutable()) BaseQuals.removeConst(); 2932 2933 Qualifiers MemberQuals 2934 = Context.getCanonicalType(MemberType).getQualifiers(); 2935 2936 Qualifiers Combined = BaseQuals + MemberQuals; 2937 if (Combined != MemberQuals) 2938 MemberType = Context.getQualifiedType(MemberType, Combined); 2939 } 2940 2941 MarkDeclarationReferenced(MemberLoc, FD); 2942 if (PerformObjectMemberConversion(BaseExpr, Qualifier, FoundDecl, FD)) 2943 return ExprError(); 2944 return Owned(BuildMemberExpr(Context, BaseExpr, IsArrow, SS, 2945 FD, FoundDecl, MemberNameInfo, 2946 MemberType)); 2947 } 2948 2949 if (VarDecl *Var = dyn_cast<VarDecl>(MemberDecl)) { 2950 MarkDeclarationReferenced(MemberLoc, Var); 2951 return Owned(BuildMemberExpr(Context, BaseExpr, IsArrow, SS, 2952 Var, FoundDecl, MemberNameInfo, 2953 Var->getType().getNonReferenceType())); 2954 } 2955 2956 if (FunctionDecl *MemberFn = dyn_cast<FunctionDecl>(MemberDecl)) { 2957 MarkDeclarationReferenced(MemberLoc, MemberDecl); 2958 return Owned(BuildMemberExpr(Context, BaseExpr, IsArrow, SS, 2959 MemberFn, FoundDecl, MemberNameInfo, 2960 MemberFn->getType())); 2961 } 2962 2963 if (EnumConstantDecl *Enum = dyn_cast<EnumConstantDecl>(MemberDecl)) { 2964 MarkDeclarationReferenced(MemberLoc, MemberDecl); 2965 return Owned(BuildMemberExpr(Context, BaseExpr, IsArrow, SS, 2966 Enum, FoundDecl, MemberNameInfo, 2967 Enum->getType())); 2968 } 2969 2970 Owned(BaseExpr); 2971 2972 // We found something that we didn't expect. Complain. 2973 if (isa<TypeDecl>(MemberDecl)) 2974 Diag(MemberLoc, diag::err_typecheck_member_reference_type) 2975 << MemberName << BaseType << int(IsArrow); 2976 else 2977 Diag(MemberLoc, diag::err_typecheck_member_reference_unknown) 2978 << MemberName << BaseType << int(IsArrow); 2979 2980 Diag(MemberDecl->getLocation(), diag::note_member_declared_here) 2981 << MemberName; 2982 R.suppressDiagnostics(); 2983 return ExprError(); 2984} 2985 2986/// Look up the given member of the given non-type-dependent 2987/// expression. This can return in one of two ways: 2988/// * If it returns a sentinel null-but-valid result, the caller will 2989/// assume that lookup was performed and the results written into 2990/// the provided structure. It will take over from there. 2991/// * Otherwise, the returned expression will be produced in place of 2992/// an ordinary member expression. 2993/// 2994/// The ObjCImpDecl bit is a gross hack that will need to be properly 2995/// fixed for ObjC++. 2996ExprResult 2997Sema::LookupMemberExpr(LookupResult &R, Expr *&BaseExpr, 2998 bool &IsArrow, SourceLocation OpLoc, 2999 CXXScopeSpec &SS, 3000 Decl *ObjCImpDecl, bool HasTemplateArgs) { 3001 assert(BaseExpr && "no base expression"); 3002 3003 // Perform default conversions. 3004 DefaultFunctionArrayConversion(BaseExpr); 3005 3006 QualType BaseType = BaseExpr->getType(); 3007 assert(!BaseType->isDependentType()); 3008 3009 DeclarationName MemberName = R.getLookupName(); 3010 SourceLocation MemberLoc = R.getNameLoc(); 3011 3012 // If the user is trying to apply -> or . to a function pointer 3013 // type, it's probably because they forgot parentheses to call that 3014 // function. Suggest the addition of those parentheses, build the 3015 // call, and continue on. 3016 if (const PointerType *Ptr = BaseType->getAs<PointerType>()) { 3017 if (const FunctionProtoType *Fun 3018 = Ptr->getPointeeType()->getAs<FunctionProtoType>()) { 3019 QualType ResultTy = Fun->getResultType(); 3020 if (Fun->getNumArgs() == 0 && 3021 ((!IsArrow && ResultTy->isRecordType()) || 3022 (IsArrow && ResultTy->isPointerType() && 3023 ResultTy->getAs<PointerType>()->getPointeeType() 3024 ->isRecordType()))) { 3025 SourceLocation Loc = PP.getLocForEndOfToken(BaseExpr->getLocEnd()); 3026 Diag(Loc, diag::err_member_reference_needs_call) 3027 << QualType(Fun, 0) 3028 << FixItHint::CreateInsertion(Loc, "()"); 3029 3030 ExprResult NewBase 3031 = ActOnCallExpr(0, BaseExpr, Loc, MultiExprArg(*this, 0, 0), Loc); 3032 BaseExpr = 0; 3033 if (NewBase.isInvalid()) 3034 return ExprError(); 3035 3036 BaseExpr = NewBase.takeAs<Expr>(); 3037 DefaultFunctionArrayConversion(BaseExpr); 3038 BaseType = BaseExpr->getType(); 3039 } 3040 } 3041 } 3042 3043 // If this is an Objective-C pseudo-builtin and a definition is provided then 3044 // use that. 3045 if (BaseType->isObjCIdType()) { 3046 if (IsArrow) { 3047 // Handle the following exceptional case PObj->isa. 3048 if (const ObjCObjectPointerType *OPT = 3049 BaseType->getAs<ObjCObjectPointerType>()) { 3050 if (OPT->getObjectType()->isObjCId() && 3051 MemberName.getAsIdentifierInfo()->isStr("isa")) 3052 return Owned(new (Context) ObjCIsaExpr(BaseExpr, true, MemberLoc, 3053 Context.getObjCClassType())); 3054 } 3055 } 3056 // We have an 'id' type. Rather than fall through, we check if this 3057 // is a reference to 'isa'. 3058 if (BaseType != Context.ObjCIdRedefinitionType) { 3059 BaseType = Context.ObjCIdRedefinitionType; 3060 ImpCastExprToType(BaseExpr, BaseType, CK_BitCast); 3061 } 3062 } 3063 3064 // If this is an Objective-C pseudo-builtin and a definition is provided then 3065 // use that. 3066 if (Context.isObjCSelType(BaseType)) { 3067 // We have an 'SEL' type. Rather than fall through, we check if this 3068 // is a reference to 'sel_id'. 3069 if (BaseType != Context.ObjCSelRedefinitionType) { 3070 BaseType = Context.ObjCSelRedefinitionType; 3071 ImpCastExprToType(BaseExpr, BaseType, CK_BitCast); 3072 } 3073 } 3074 3075 assert(!BaseType.isNull() && "no type for member expression"); 3076 3077 // Handle properties on ObjC 'Class' types. 3078 if (!IsArrow && BaseType->isObjCClassType()) { 3079 // Also must look for a getter name which uses property syntax. 3080 IdentifierInfo *Member = MemberName.getAsIdentifierInfo(); 3081 Selector Sel = PP.getSelectorTable().getNullarySelector(Member); 3082 if (ObjCMethodDecl *MD = getCurMethodDecl()) { 3083 ObjCInterfaceDecl *IFace = MD->getClassInterface(); 3084 ObjCMethodDecl *Getter; 3085 // FIXME: need to also look locally in the implementation. 3086 if ((Getter = IFace->lookupClassMethod(Sel))) { 3087 // Check the use of this method. 3088 if (DiagnoseUseOfDecl(Getter, MemberLoc)) 3089 return ExprError(); 3090 } 3091 // If we found a getter then this may be a valid dot-reference, we 3092 // will look for the matching setter, in case it is needed. 3093 Selector SetterSel = 3094 SelectorTable::constructSetterName(PP.getIdentifierTable(), 3095 PP.getSelectorTable(), Member); 3096 ObjCMethodDecl *Setter = IFace->lookupClassMethod(SetterSel); 3097 if (!Setter) { 3098 // If this reference is in an @implementation, also check for 'private' 3099 // methods. 3100 Setter = IFace->lookupPrivateInstanceMethod(SetterSel); 3101 } 3102 // Look through local category implementations associated with the class. 3103 if (!Setter) 3104 Setter = IFace->getCategoryClassMethod(SetterSel); 3105 3106 if (Setter && DiagnoseUseOfDecl(Setter, MemberLoc)) 3107 return ExprError(); 3108 3109 if (Getter || Setter) { 3110 QualType PType; 3111 3112 if (Getter) 3113 PType = Getter->getSendResultType(); 3114 else 3115 // Get the expression type from Setter's incoming parameter. 3116 PType = (*(Setter->param_end() -1))->getType(); 3117 // FIXME: we must check that the setter has property type. 3118 return Owned(new (Context) ObjCImplicitSetterGetterRefExpr(Getter, 3119 PType, 3120 Setter, MemberLoc, BaseExpr)); 3121 } 3122 return ExprError(Diag(MemberLoc, diag::err_property_not_found) 3123 << MemberName << BaseType); 3124 } 3125 } 3126 3127 if (BaseType->isObjCClassType() && 3128 BaseType != Context.ObjCClassRedefinitionType) { 3129 BaseType = Context.ObjCClassRedefinitionType; 3130 ImpCastExprToType(BaseExpr, BaseType, CK_BitCast); 3131 } 3132 3133 if (IsArrow) { 3134 if (const PointerType *PT = BaseType->getAs<PointerType>()) 3135 BaseType = PT->getPointeeType(); 3136 else if (BaseType->isObjCObjectPointerType()) 3137 ; 3138 else if (BaseType->isRecordType()) { 3139 // Recover from arrow accesses to records, e.g.: 3140 // struct MyRecord foo; 3141 // foo->bar 3142 // This is actually well-formed in C++ if MyRecord has an 3143 // overloaded operator->, but that should have been dealt with 3144 // by now. 3145 Diag(OpLoc, diag::err_typecheck_member_reference_suggestion) 3146 << BaseType << int(IsArrow) << BaseExpr->getSourceRange() 3147 << FixItHint::CreateReplacement(OpLoc, "."); 3148 IsArrow = false; 3149 } else { 3150 Diag(MemberLoc, diag::err_typecheck_member_reference_arrow) 3151 << BaseType << BaseExpr->getSourceRange(); 3152 return ExprError(); 3153 } 3154 } else { 3155 // Recover from dot accesses to pointers, e.g.: 3156 // type *foo; 3157 // foo.bar 3158 // This is actually well-formed in two cases: 3159 // - 'type' is an Objective C type 3160 // - 'bar' is a pseudo-destructor name which happens to refer to 3161 // the appropriate pointer type 3162 if (MemberName.getNameKind() != DeclarationName::CXXDestructorName) { 3163 const PointerType *PT = BaseType->getAs<PointerType>(); 3164 if (PT && PT->getPointeeType()->isRecordType()) { 3165 Diag(OpLoc, diag::err_typecheck_member_reference_suggestion) 3166 << BaseType << int(IsArrow) << BaseExpr->getSourceRange() 3167 << FixItHint::CreateReplacement(OpLoc, "->"); 3168 BaseType = PT->getPointeeType(); 3169 IsArrow = true; 3170 } 3171 } 3172 } 3173 3174 // Handle field access to simple records. 3175 if (const RecordType *RTy = BaseType->getAs<RecordType>()) { 3176 if (LookupMemberExprInRecord(*this, R, BaseExpr->getSourceRange(), 3177 RTy, OpLoc, SS, HasTemplateArgs)) 3178 return ExprError(); 3179 return Owned((Expr*) 0); 3180 } 3181 3182 // Handle access to Objective-C instance variables, such as "Obj->ivar" and 3183 // (*Obj).ivar. 3184 if ((IsArrow && BaseType->isObjCObjectPointerType()) || 3185 (!IsArrow && BaseType->isObjCObjectType())) { 3186 const ObjCObjectPointerType *OPT = BaseType->getAs<ObjCObjectPointerType>(); 3187 ObjCInterfaceDecl *IDecl = 3188 OPT ? OPT->getInterfaceDecl() 3189 : BaseType->getAs<ObjCObjectType>()->getInterface(); 3190 if (IDecl) { 3191 IdentifierInfo *Member = MemberName.getAsIdentifierInfo(); 3192 3193 ObjCInterfaceDecl *ClassDeclared; 3194 ObjCIvarDecl *IV = IDecl->lookupInstanceVariable(Member, ClassDeclared); 3195 3196 if (!IV) { 3197 // Attempt to correct for typos in ivar names. 3198 LookupResult Res(*this, R.getLookupName(), R.getNameLoc(), 3199 LookupMemberName); 3200 if (CorrectTypo(Res, 0, 0, IDecl, false, CTC_MemberLookup) && 3201 (IV = Res.getAsSingle<ObjCIvarDecl>())) { 3202 Diag(R.getNameLoc(), 3203 diag::err_typecheck_member_reference_ivar_suggest) 3204 << IDecl->getDeclName() << MemberName << IV->getDeclName() 3205 << FixItHint::CreateReplacement(R.getNameLoc(), 3206 IV->getNameAsString()); 3207 Diag(IV->getLocation(), diag::note_previous_decl) 3208 << IV->getDeclName(); 3209 } else { 3210 Res.clear(); 3211 Res.setLookupName(Member); 3212 } 3213 } 3214 3215 if (IV) { 3216 // If the decl being referenced had an error, return an error for this 3217 // sub-expr without emitting another error, in order to avoid cascading 3218 // error cases. 3219 if (IV->isInvalidDecl()) 3220 return ExprError(); 3221 3222 // Check whether we can reference this field. 3223 if (DiagnoseUseOfDecl(IV, MemberLoc)) 3224 return ExprError(); 3225 if (IV->getAccessControl() != ObjCIvarDecl::Public && 3226 IV->getAccessControl() != ObjCIvarDecl::Package) { 3227 ObjCInterfaceDecl *ClassOfMethodDecl = 0; 3228 if (ObjCMethodDecl *MD = getCurMethodDecl()) 3229 ClassOfMethodDecl = MD->getClassInterface(); 3230 else if (ObjCImpDecl && getCurFunctionDecl()) { 3231 // Case of a c-function declared inside an objc implementation. 3232 // FIXME: For a c-style function nested inside an objc implementation 3233 // class, there is no implementation context available, so we pass 3234 // down the context as argument to this routine. Ideally, this context 3235 // need be passed down in the AST node and somehow calculated from the 3236 // AST for a function decl. 3237 if (ObjCImplementationDecl *IMPD = 3238 dyn_cast<ObjCImplementationDecl>(ObjCImpDecl)) 3239 ClassOfMethodDecl = IMPD->getClassInterface(); 3240 else if (ObjCCategoryImplDecl* CatImplClass = 3241 dyn_cast<ObjCCategoryImplDecl>(ObjCImpDecl)) 3242 ClassOfMethodDecl = CatImplClass->getClassInterface(); 3243 } 3244 3245 if (IV->getAccessControl() == ObjCIvarDecl::Private) { 3246 if (ClassDeclared != IDecl || 3247 ClassOfMethodDecl != ClassDeclared) 3248 Diag(MemberLoc, diag::error_private_ivar_access) 3249 << IV->getDeclName(); 3250 } else if (!IDecl->isSuperClassOf(ClassOfMethodDecl)) 3251 // @protected 3252 Diag(MemberLoc, diag::error_protected_ivar_access) 3253 << IV->getDeclName(); 3254 } 3255 3256 return Owned(new (Context) ObjCIvarRefExpr(IV, IV->getType(), 3257 MemberLoc, BaseExpr, 3258 IsArrow)); 3259 } 3260 return ExprError(Diag(MemberLoc, diag::err_typecheck_member_reference_ivar) 3261 << IDecl->getDeclName() << MemberName 3262 << BaseExpr->getSourceRange()); 3263 } 3264 } 3265 // Handle properties on 'id' and qualified "id". 3266 if (!IsArrow && (BaseType->isObjCIdType() || 3267 BaseType->isObjCQualifiedIdType())) { 3268 const ObjCObjectPointerType *QIdTy = BaseType->getAs<ObjCObjectPointerType>(); 3269 IdentifierInfo *Member = MemberName.getAsIdentifierInfo(); 3270 3271 // Check protocols on qualified interfaces. 3272 Selector Sel = PP.getSelectorTable().getNullarySelector(Member); 3273 if (Decl *PMDecl = FindGetterNameDecl(QIdTy, Member, Sel, Context)) { 3274 if (ObjCPropertyDecl *PD = dyn_cast<ObjCPropertyDecl>(PMDecl)) { 3275 // Check the use of this declaration 3276 if (DiagnoseUseOfDecl(PD, MemberLoc)) 3277 return ExprError(); 3278 3279 return Owned(new (Context) ObjCPropertyRefExpr(PD, PD->getType(), 3280 MemberLoc, BaseExpr)); 3281 } 3282 if (ObjCMethodDecl *OMD = dyn_cast<ObjCMethodDecl>(PMDecl)) { 3283 // Check the use of this method. 3284 if (DiagnoseUseOfDecl(OMD, MemberLoc)) 3285 return ExprError(); 3286 3287 return Owned(ObjCMessageExpr::Create(Context, 3288 OMD->getSendResultType(), 3289 OpLoc, BaseExpr, Sel, 3290 OMD, NULL, 0, MemberLoc)); 3291 } 3292 } 3293 3294 return ExprError(Diag(MemberLoc, diag::err_property_not_found) 3295 << MemberName << BaseType); 3296 } 3297 3298 // Handle Objective-C property access, which is "Obj.property" where Obj is a 3299 // pointer to a (potentially qualified) interface type. 3300 if (!IsArrow) 3301 if (const ObjCObjectPointerType *OPT = 3302 BaseType->getAsObjCInterfacePointerType()) 3303 return HandleExprPropertyRefExpr(OPT, BaseExpr, MemberName, MemberLoc); 3304 3305 // Handle the following exceptional case (*Obj).isa. 3306 if (!IsArrow && 3307 BaseType->isObjCObjectType() && 3308 BaseType->getAs<ObjCObjectType>()->isObjCId() && 3309 MemberName.getAsIdentifierInfo()->isStr("isa")) 3310 return Owned(new (Context) ObjCIsaExpr(BaseExpr, false, MemberLoc, 3311 Context.getObjCClassType())); 3312 3313 // Handle 'field access' to vectors, such as 'V.xx'. 3314 if (BaseType->isExtVectorType()) { 3315 IdentifierInfo *Member = MemberName.getAsIdentifierInfo(); 3316 QualType ret = CheckExtVectorComponent(BaseType, OpLoc, Member, MemberLoc); 3317 if (ret.isNull()) 3318 return ExprError(); 3319 return Owned(new (Context) ExtVectorElementExpr(ret, BaseExpr, *Member, 3320 MemberLoc)); 3321 } 3322 3323 Diag(MemberLoc, diag::err_typecheck_member_reference_struct_union) 3324 << BaseType << BaseExpr->getSourceRange(); 3325 3326 return ExprError(); 3327} 3328 3329/// The main callback when the parser finds something like 3330/// expression . [nested-name-specifier] identifier 3331/// expression -> [nested-name-specifier] identifier 3332/// where 'identifier' encompasses a fairly broad spectrum of 3333/// possibilities, including destructor and operator references. 3334/// 3335/// \param OpKind either tok::arrow or tok::period 3336/// \param HasTrailingLParen whether the next token is '(', which 3337/// is used to diagnose mis-uses of special members that can 3338/// only be called 3339/// \param ObjCImpDecl the current ObjC @implementation decl; 3340/// this is an ugly hack around the fact that ObjC @implementations 3341/// aren't properly put in the context chain 3342ExprResult Sema::ActOnMemberAccessExpr(Scope *S, Expr *Base, 3343 SourceLocation OpLoc, 3344 tok::TokenKind OpKind, 3345 CXXScopeSpec &SS, 3346 UnqualifiedId &Id, 3347 Decl *ObjCImpDecl, 3348 bool HasTrailingLParen) { 3349 if (SS.isSet() && SS.isInvalid()) 3350 return ExprError(); 3351 3352 TemplateArgumentListInfo TemplateArgsBuffer; 3353 3354 // Decompose the name into its component parts. 3355 DeclarationNameInfo NameInfo; 3356 const TemplateArgumentListInfo *TemplateArgs; 3357 DecomposeUnqualifiedId(*this, Id, TemplateArgsBuffer, 3358 NameInfo, TemplateArgs); 3359 3360 DeclarationName Name = NameInfo.getName(); 3361 bool IsArrow = (OpKind == tok::arrow); 3362 3363 NamedDecl *FirstQualifierInScope 3364 = (!SS.isSet() ? 0 : FindFirstQualifierInScope(S, 3365 static_cast<NestedNameSpecifier*>(SS.getScopeRep()))); 3366 3367 // This is a postfix expression, so get rid of ParenListExprs. 3368 ExprResult Result = MaybeConvertParenListExprToParenExpr(S, Base); 3369 if (Result.isInvalid()) return ExprError(); 3370 Base = Result.take(); 3371 3372 if (Base->getType()->isDependentType() || Name.isDependentName() || 3373 isDependentScopeSpecifier(SS)) { 3374 Result = ActOnDependentMemberExpr(Base, Base->getType(), 3375 IsArrow, OpLoc, 3376 SS, FirstQualifierInScope, 3377 NameInfo, TemplateArgs); 3378 } else { 3379 LookupResult R(*this, NameInfo, LookupMemberName); 3380 Result = LookupMemberExpr(R, Base, IsArrow, OpLoc, 3381 SS, ObjCImpDecl, TemplateArgs != 0); 3382 3383 if (Result.isInvalid()) { 3384 Owned(Base); 3385 return ExprError(); 3386 } 3387 3388 if (Result.get()) { 3389 // The only way a reference to a destructor can be used is to 3390 // immediately call it, which falls into this case. If the 3391 // next token is not a '(', produce a diagnostic and build the 3392 // call now. 3393 if (!HasTrailingLParen && 3394 Id.getKind() == UnqualifiedId::IK_DestructorName) 3395 return DiagnoseDtorReference(NameInfo.getLoc(), Result.get()); 3396 3397 return move(Result); 3398 } 3399 3400 Result = BuildMemberReferenceExpr(Base, Base->getType(), 3401 OpLoc, IsArrow, SS, FirstQualifierInScope, 3402 R, TemplateArgs); 3403 } 3404 3405 return move(Result); 3406} 3407 3408ExprResult Sema::BuildCXXDefaultArgExpr(SourceLocation CallLoc, 3409 FunctionDecl *FD, 3410 ParmVarDecl *Param) { 3411 if (Param->hasUnparsedDefaultArg()) { 3412 Diag(CallLoc, 3413 diag::err_use_of_default_argument_to_function_declared_later) << 3414 FD << cast<CXXRecordDecl>(FD->getDeclContext())->getDeclName(); 3415 Diag(UnparsedDefaultArgLocs[Param], 3416 diag::note_default_argument_declared_here); 3417 return ExprError(); 3418 } 3419 3420 if (Param->hasUninstantiatedDefaultArg()) { 3421 Expr *UninstExpr = Param->getUninstantiatedDefaultArg(); 3422 3423 // Instantiate the expression. 3424 MultiLevelTemplateArgumentList ArgList 3425 = getTemplateInstantiationArgs(FD, 0, /*RelativeToPrimary=*/true); 3426 3427 std::pair<const TemplateArgument *, unsigned> Innermost 3428 = ArgList.getInnermost(); 3429 InstantiatingTemplate Inst(*this, CallLoc, Param, Innermost.first, 3430 Innermost.second); 3431 3432 ExprResult Result = SubstExpr(UninstExpr, ArgList); 3433 if (Result.isInvalid()) 3434 return ExprError(); 3435 3436 // Check the expression as an initializer for the parameter. 3437 InitializedEntity Entity 3438 = InitializedEntity::InitializeParameter(Param); 3439 InitializationKind Kind 3440 = InitializationKind::CreateCopy(Param->getLocation(), 3441 /*FIXME:EqualLoc*/UninstExpr->getSourceRange().getBegin()); 3442 Expr *ResultE = Result.takeAs<Expr>(); 3443 3444 InitializationSequence InitSeq(*this, Entity, Kind, &ResultE, 1); 3445 Result = InitSeq.Perform(*this, Entity, Kind, 3446 MultiExprArg(*this, &ResultE, 1)); 3447 if (Result.isInvalid()) 3448 return ExprError(); 3449 3450 // Build the default argument expression. 3451 return Owned(CXXDefaultArgExpr::Create(Context, CallLoc, Param, 3452 Result.takeAs<Expr>())); 3453 } 3454 3455 // If the default expression creates temporaries, we need to 3456 // push them to the current stack of expression temporaries so they'll 3457 // be properly destroyed. 3458 // FIXME: We should really be rebuilding the default argument with new 3459 // bound temporaries; see the comment in PR5810. 3460 for (unsigned i = 0, e = Param->getNumDefaultArgTemporaries(); i != e; ++i) { 3461 CXXTemporary *Temporary = Param->getDefaultArgTemporary(i); 3462 MarkDeclarationReferenced(Param->getDefaultArg()->getLocStart(), 3463 const_cast<CXXDestructorDecl*>(Temporary->getDestructor())); 3464 ExprTemporaries.push_back(Temporary); 3465 } 3466 3467 // We already type-checked the argument, so we know it works. 3468 // Just mark all of the declarations in this potentially-evaluated expression 3469 // as being "referenced". 3470 MarkDeclarationsReferencedInExpr(Param->getDefaultArg()); 3471 return Owned(CXXDefaultArgExpr::Create(Context, CallLoc, Param)); 3472} 3473 3474/// ConvertArgumentsForCall - Converts the arguments specified in 3475/// Args/NumArgs to the parameter types of the function FDecl with 3476/// function prototype Proto. Call is the call expression itself, and 3477/// Fn is the function expression. For a C++ member function, this 3478/// routine does not attempt to convert the object argument. Returns 3479/// true if the call is ill-formed. 3480bool 3481Sema::ConvertArgumentsForCall(CallExpr *Call, Expr *Fn, 3482 FunctionDecl *FDecl, 3483 const FunctionProtoType *Proto, 3484 Expr **Args, unsigned NumArgs, 3485 SourceLocation RParenLoc) { 3486 // C99 6.5.2.2p7 - the arguments are implicitly converted, as if by 3487 // assignment, to the types of the corresponding parameter, ... 3488 unsigned NumArgsInProto = Proto->getNumArgs(); 3489 bool Invalid = false; 3490 3491 // If too few arguments are available (and we don't have default 3492 // arguments for the remaining parameters), don't make the call. 3493 if (NumArgs < NumArgsInProto) { 3494 if (!FDecl || NumArgs < FDecl->getMinRequiredArguments()) 3495 return Diag(RParenLoc, diag::err_typecheck_call_too_few_args) 3496 << Fn->getType()->isBlockPointerType() 3497 << NumArgsInProto << NumArgs << Fn->getSourceRange(); 3498 Call->setNumArgs(Context, NumArgsInProto); 3499 } 3500 3501 // If too many are passed and not variadic, error on the extras and drop 3502 // them. 3503 if (NumArgs > NumArgsInProto) { 3504 if (!Proto->isVariadic()) { 3505 Diag(Args[NumArgsInProto]->getLocStart(), 3506 diag::err_typecheck_call_too_many_args) 3507 << Fn->getType()->isBlockPointerType() 3508 << NumArgsInProto << NumArgs << Fn->getSourceRange() 3509 << SourceRange(Args[NumArgsInProto]->getLocStart(), 3510 Args[NumArgs-1]->getLocEnd()); 3511 // This deletes the extra arguments. 3512 Call->setNumArgs(Context, NumArgsInProto); 3513 return true; 3514 } 3515 } 3516 llvm::SmallVector<Expr *, 8> AllArgs; 3517 VariadicCallType CallType = 3518 Proto->isVariadic() ? VariadicFunction : VariadicDoesNotApply; 3519 if (Fn->getType()->isBlockPointerType()) 3520 CallType = VariadicBlock; // Block 3521 else if (isa<MemberExpr>(Fn)) 3522 CallType = VariadicMethod; 3523 Invalid = GatherArgumentsForCall(Call->getSourceRange().getBegin(), FDecl, 3524 Proto, 0, Args, NumArgs, AllArgs, CallType); 3525 if (Invalid) 3526 return true; 3527 unsigned TotalNumArgs = AllArgs.size(); 3528 for (unsigned i = 0; i < TotalNumArgs; ++i) 3529 Call->setArg(i, AllArgs[i]); 3530 3531 return false; 3532} 3533 3534bool Sema::GatherArgumentsForCall(SourceLocation CallLoc, 3535 FunctionDecl *FDecl, 3536 const FunctionProtoType *Proto, 3537 unsigned FirstProtoArg, 3538 Expr **Args, unsigned NumArgs, 3539 llvm::SmallVector<Expr *, 8> &AllArgs, 3540 VariadicCallType CallType) { 3541 unsigned NumArgsInProto = Proto->getNumArgs(); 3542 unsigned NumArgsToCheck = NumArgs; 3543 bool Invalid = false; 3544 if (NumArgs != NumArgsInProto) 3545 // Use default arguments for missing arguments 3546 NumArgsToCheck = NumArgsInProto; 3547 unsigned ArgIx = 0; 3548 // Continue to check argument types (even if we have too few/many args). 3549 for (unsigned i = FirstProtoArg; i != NumArgsToCheck; i++) { 3550 QualType ProtoArgType = Proto->getArgType(i); 3551 3552 Expr *Arg; 3553 if (ArgIx < NumArgs) { 3554 Arg = Args[ArgIx++]; 3555 3556 if (RequireCompleteType(Arg->getSourceRange().getBegin(), 3557 ProtoArgType, 3558 PDiag(diag::err_call_incomplete_argument) 3559 << Arg->getSourceRange())) 3560 return true; 3561 3562 // Pass the argument 3563 ParmVarDecl *Param = 0; 3564 if (FDecl && i < FDecl->getNumParams()) 3565 Param = FDecl->getParamDecl(i); 3566 3567 3568 InitializedEntity Entity = 3569 Param? InitializedEntity::InitializeParameter(Param) 3570 : InitializedEntity::InitializeParameter(ProtoArgType); 3571 ExprResult ArgE = PerformCopyInitialization(Entity, 3572 SourceLocation(), 3573 Owned(Arg)); 3574 if (ArgE.isInvalid()) 3575 return true; 3576 3577 Arg = ArgE.takeAs<Expr>(); 3578 } else { 3579 ParmVarDecl *Param = FDecl->getParamDecl(i); 3580 3581 ExprResult ArgExpr = 3582 BuildCXXDefaultArgExpr(CallLoc, FDecl, Param); 3583 if (ArgExpr.isInvalid()) 3584 return true; 3585 3586 Arg = ArgExpr.takeAs<Expr>(); 3587 } 3588 AllArgs.push_back(Arg); 3589 } 3590 3591 // If this is a variadic call, handle args passed through "...". 3592 if (CallType != VariadicDoesNotApply) { 3593 // Promote the arguments (C99 6.5.2.2p7). 3594 for (unsigned i = ArgIx; i != NumArgs; ++i) { 3595 Expr *Arg = Args[i]; 3596 Invalid |= DefaultVariadicArgumentPromotion(Arg, CallType, FDecl); 3597 AllArgs.push_back(Arg); 3598 } 3599 } 3600 return Invalid; 3601} 3602 3603/// ActOnCallExpr - Handle a call to Fn with the specified array of arguments. 3604/// This provides the location of the left/right parens and a list of comma 3605/// locations. 3606ExprResult 3607Sema::ActOnCallExpr(Scope *S, Expr *Fn, SourceLocation LParenLoc, 3608 MultiExprArg args, SourceLocation RParenLoc) { 3609 unsigned NumArgs = args.size(); 3610 3611 // Since this might be a postfix expression, get rid of ParenListExprs. 3612 ExprResult Result = MaybeConvertParenListExprToParenExpr(S, Fn); 3613 if (Result.isInvalid()) return ExprError(); 3614 Fn = Result.take(); 3615 3616 Expr **Args = args.release(); 3617 3618 if (getLangOptions().CPlusPlus) { 3619 // If this is a pseudo-destructor expression, build the call immediately. 3620 if (isa<CXXPseudoDestructorExpr>(Fn)) { 3621 if (NumArgs > 0) { 3622 // Pseudo-destructor calls should not have any arguments. 3623 Diag(Fn->getLocStart(), diag::err_pseudo_dtor_call_with_args) 3624 << FixItHint::CreateRemoval( 3625 SourceRange(Args[0]->getLocStart(), 3626 Args[NumArgs-1]->getLocEnd())); 3627 3628 NumArgs = 0; 3629 } 3630 3631 return Owned(new (Context) CallExpr(Context, Fn, 0, 0, Context.VoidTy, 3632 RParenLoc)); 3633 } 3634 3635 // Determine whether this is a dependent call inside a C++ template, 3636 // in which case we won't do any semantic analysis now. 3637 // FIXME: Will need to cache the results of name lookup (including ADL) in 3638 // Fn. 3639 bool Dependent = false; 3640 if (Fn->isTypeDependent()) 3641 Dependent = true; 3642 else if (Expr::hasAnyTypeDependentArguments(Args, NumArgs)) 3643 Dependent = true; 3644 3645 if (Dependent) 3646 return Owned(new (Context) CallExpr(Context, Fn, Args, NumArgs, 3647 Context.DependentTy, RParenLoc)); 3648 3649 // Determine whether this is a call to an object (C++ [over.call.object]). 3650 if (Fn->getType()->isRecordType()) 3651 return Owned(BuildCallToObjectOfClassType(S, Fn, LParenLoc, Args, NumArgs, 3652 RParenLoc)); 3653 3654 Expr *NakedFn = Fn->IgnoreParens(); 3655 3656 // Determine whether this is a call to an unresolved member function. 3657 if (UnresolvedMemberExpr *MemE = dyn_cast<UnresolvedMemberExpr>(NakedFn)) { 3658 // If lookup was unresolved but not dependent (i.e. didn't find 3659 // an unresolved using declaration), it has to be an overloaded 3660 // function set, which means it must contain either multiple 3661 // declarations (all methods or method templates) or a single 3662 // method template. 3663 assert((MemE->getNumDecls() > 1) || 3664 isa<FunctionTemplateDecl>( 3665 (*MemE->decls_begin())->getUnderlyingDecl())); 3666 (void)MemE; 3667 3668 return BuildCallToMemberFunction(S, Fn, LParenLoc, Args, NumArgs, 3669 RParenLoc); 3670 } 3671 3672 // Determine whether this is a call to a member function. 3673 if (MemberExpr *MemExpr = dyn_cast<MemberExpr>(NakedFn)) { 3674 NamedDecl *MemDecl = MemExpr->getMemberDecl(); 3675 if (isa<CXXMethodDecl>(MemDecl)) 3676 return BuildCallToMemberFunction(S, Fn, LParenLoc, Args, NumArgs, 3677 RParenLoc); 3678 } 3679 3680 // Determine whether this is a call to a pointer-to-member function. 3681 if (BinaryOperator *BO = dyn_cast<BinaryOperator>(NakedFn)) { 3682 if (BO->getOpcode() == BO_PtrMemD || 3683 BO->getOpcode() == BO_PtrMemI) { 3684 if (const FunctionProtoType *FPT 3685 = BO->getType()->getAs<FunctionProtoType>()) { 3686 QualType ResultTy = FPT->getCallResultType(Context); 3687 3688 CXXMemberCallExpr *TheCall 3689 = new (Context) CXXMemberCallExpr(Context, BO, Args, 3690 NumArgs, ResultTy, 3691 RParenLoc); 3692 3693 if (CheckCallReturnType(FPT->getResultType(), 3694 BO->getRHS()->getSourceRange().getBegin(), 3695 TheCall, 0)) 3696 return ExprError(); 3697 3698 if (ConvertArgumentsForCall(TheCall, BO, 0, FPT, Args, NumArgs, 3699 RParenLoc)) 3700 return ExprError(); 3701 3702 return MaybeBindToTemporary(TheCall); 3703 } 3704 return ExprError(Diag(Fn->getLocStart(), 3705 diag::err_typecheck_call_not_function) 3706 << Fn->getType() << Fn->getSourceRange()); 3707 } 3708 } 3709 } 3710 3711 // If we're directly calling a function, get the appropriate declaration. 3712 // Also, in C++, keep track of whether we should perform argument-dependent 3713 // lookup and whether there were any explicitly-specified template arguments. 3714 3715 Expr *NakedFn = Fn->IgnoreParens(); 3716 if (isa<UnresolvedLookupExpr>(NakedFn)) { 3717 UnresolvedLookupExpr *ULE = cast<UnresolvedLookupExpr>(NakedFn); 3718 return BuildOverloadedCallExpr(S, Fn, ULE, LParenLoc, Args, NumArgs, 3719 RParenLoc); 3720 } 3721 3722 NamedDecl *NDecl = 0; 3723 if (isa<DeclRefExpr>(NakedFn)) 3724 NDecl = cast<DeclRefExpr>(NakedFn)->getDecl(); 3725 3726 return BuildResolvedCallExpr(Fn, NDecl, LParenLoc, Args, NumArgs, RParenLoc); 3727} 3728 3729/// BuildResolvedCallExpr - Build a call to a resolved expression, 3730/// i.e. an expression not of \p OverloadTy. The expression should 3731/// unary-convert to an expression of function-pointer or 3732/// block-pointer type. 3733/// 3734/// \param NDecl the declaration being called, if available 3735ExprResult 3736Sema::BuildResolvedCallExpr(Expr *Fn, NamedDecl *NDecl, 3737 SourceLocation LParenLoc, 3738 Expr **Args, unsigned NumArgs, 3739 SourceLocation RParenLoc) { 3740 FunctionDecl *FDecl = dyn_cast_or_null<FunctionDecl>(NDecl); 3741 3742 // Promote the function operand. 3743 UsualUnaryConversions(Fn); 3744 3745 // Make the call expr early, before semantic checks. This guarantees cleanup 3746 // of arguments and function on error. 3747 CallExpr *TheCall = new (Context) CallExpr(Context, Fn, 3748 Args, NumArgs, 3749 Context.BoolTy, 3750 RParenLoc); 3751 3752 const FunctionType *FuncT; 3753 if (!Fn->getType()->isBlockPointerType()) { 3754 // C99 6.5.2.2p1 - "The expression that denotes the called function shall 3755 // have type pointer to function". 3756 const PointerType *PT = Fn->getType()->getAs<PointerType>(); 3757 if (PT == 0) 3758 return ExprError(Diag(LParenLoc, diag::err_typecheck_call_not_function) 3759 << Fn->getType() << Fn->getSourceRange()); 3760 FuncT = PT->getPointeeType()->getAs<FunctionType>(); 3761 } else { // This is a block call. 3762 FuncT = Fn->getType()->getAs<BlockPointerType>()->getPointeeType()-> 3763 getAs<FunctionType>(); 3764 } 3765 if (FuncT == 0) 3766 return ExprError(Diag(LParenLoc, diag::err_typecheck_call_not_function) 3767 << Fn->getType() << Fn->getSourceRange()); 3768 3769 // Check for a valid return type 3770 if (CheckCallReturnType(FuncT->getResultType(), 3771 Fn->getSourceRange().getBegin(), TheCall, 3772 FDecl)) 3773 return ExprError(); 3774 3775 // We know the result type of the call, set it. 3776 TheCall->setType(FuncT->getCallResultType(Context)); 3777 3778 if (const FunctionProtoType *Proto = dyn_cast<FunctionProtoType>(FuncT)) { 3779 if (ConvertArgumentsForCall(TheCall, Fn, FDecl, Proto, Args, NumArgs, 3780 RParenLoc)) 3781 return ExprError(); 3782 } else { 3783 assert(isa<FunctionNoProtoType>(FuncT) && "Unknown FunctionType!"); 3784 3785 if (FDecl) { 3786 // Check if we have too few/too many template arguments, based 3787 // on our knowledge of the function definition. 3788 const FunctionDecl *Def = 0; 3789 if (FDecl->hasBody(Def) && NumArgs != Def->param_size()) { 3790 const FunctionProtoType *Proto = 3791 Def->getType()->getAs<FunctionProtoType>(); 3792 if (!Proto || !(Proto->isVariadic() && NumArgs >= Def->param_size())) { 3793 Diag(RParenLoc, diag::warn_call_wrong_number_of_arguments) 3794 << (NumArgs > Def->param_size()) << FDecl << Fn->getSourceRange(); 3795 } 3796 } 3797 } 3798 3799 // Promote the arguments (C99 6.5.2.2p6). 3800 for (unsigned i = 0; i != NumArgs; i++) { 3801 Expr *Arg = Args[i]; 3802 DefaultArgumentPromotion(Arg); 3803 if (RequireCompleteType(Arg->getSourceRange().getBegin(), 3804 Arg->getType(), 3805 PDiag(diag::err_call_incomplete_argument) 3806 << Arg->getSourceRange())) 3807 return ExprError(); 3808 TheCall->setArg(i, Arg); 3809 } 3810 } 3811 3812 if (CXXMethodDecl *Method = dyn_cast_or_null<CXXMethodDecl>(FDecl)) 3813 if (!Method->isStatic()) 3814 return ExprError(Diag(LParenLoc, diag::err_member_call_without_object) 3815 << Fn->getSourceRange()); 3816 3817 // Check for sentinels 3818 if (NDecl) 3819 DiagnoseSentinelCalls(NDecl, LParenLoc, Args, NumArgs); 3820 3821 // Do special checking on direct calls to functions. 3822 if (FDecl) { 3823 if (CheckFunctionCall(FDecl, TheCall)) 3824 return ExprError(); 3825 3826 if (unsigned BuiltinID = FDecl->getBuiltinID()) 3827 return CheckBuiltinFunctionCall(BuiltinID, TheCall); 3828 } else if (NDecl) { 3829 if (CheckBlockCall(NDecl, TheCall)) 3830 return ExprError(); 3831 } 3832 3833 return MaybeBindToTemporary(TheCall); 3834} 3835 3836ExprResult 3837Sema::ActOnCompoundLiteral(SourceLocation LParenLoc, ParsedType Ty, 3838 SourceLocation RParenLoc, Expr *InitExpr) { 3839 assert((Ty != 0) && "ActOnCompoundLiteral(): missing type"); 3840 // FIXME: put back this assert when initializers are worked out. 3841 //assert((InitExpr != 0) && "ActOnCompoundLiteral(): missing expression"); 3842 3843 TypeSourceInfo *TInfo; 3844 QualType literalType = GetTypeFromParser(Ty, &TInfo); 3845 if (!TInfo) 3846 TInfo = Context.getTrivialTypeSourceInfo(literalType); 3847 3848 return BuildCompoundLiteralExpr(LParenLoc, TInfo, RParenLoc, InitExpr); 3849} 3850 3851ExprResult 3852Sema::BuildCompoundLiteralExpr(SourceLocation LParenLoc, TypeSourceInfo *TInfo, 3853 SourceLocation RParenLoc, Expr *literalExpr) { 3854 QualType literalType = TInfo->getType(); 3855 3856 if (literalType->isArrayType()) { 3857 if (literalType->isVariableArrayType()) 3858 return ExprError(Diag(LParenLoc, diag::err_variable_object_no_init) 3859 << SourceRange(LParenLoc, literalExpr->getSourceRange().getEnd())); 3860 } else if (!literalType->isDependentType() && 3861 RequireCompleteType(LParenLoc, literalType, 3862 PDiag(diag::err_typecheck_decl_incomplete_type) 3863 << SourceRange(LParenLoc, 3864 literalExpr->getSourceRange().getEnd()))) 3865 return ExprError(); 3866 3867 InitializedEntity Entity 3868 = InitializedEntity::InitializeTemporary(literalType); 3869 InitializationKind Kind 3870 = InitializationKind::CreateCast(SourceRange(LParenLoc, RParenLoc), 3871 /*IsCStyleCast=*/true); 3872 InitializationSequence InitSeq(*this, Entity, Kind, &literalExpr, 1); 3873 ExprResult Result = InitSeq.Perform(*this, Entity, Kind, 3874 MultiExprArg(*this, &literalExpr, 1), 3875 &literalType); 3876 if (Result.isInvalid()) 3877 return ExprError(); 3878 literalExpr = Result.get(); 3879 3880 bool isFileScope = getCurFunctionOrMethodDecl() == 0; 3881 if (isFileScope) { // 6.5.2.5p3 3882 if (CheckForConstantInitializer(literalExpr, literalType)) 3883 return ExprError(); 3884 } 3885 3886 return Owned(new (Context) CompoundLiteralExpr(LParenLoc, TInfo, literalType, 3887 literalExpr, isFileScope)); 3888} 3889 3890ExprResult 3891Sema::ActOnInitList(SourceLocation LBraceLoc, MultiExprArg initlist, 3892 SourceLocation RBraceLoc) { 3893 unsigned NumInit = initlist.size(); 3894 Expr **InitList = initlist.release(); 3895 3896 // Semantic analysis for initializers is done by ActOnDeclarator() and 3897 // CheckInitializer() - it requires knowledge of the object being intialized. 3898 3899 InitListExpr *E = new (Context) InitListExpr(Context, LBraceLoc, InitList, 3900 NumInit, RBraceLoc); 3901 E->setType(Context.VoidTy); // FIXME: just a place holder for now. 3902 return Owned(E); 3903} 3904 3905static CastKind getScalarCastKind(ASTContext &Context, 3906 QualType SrcTy, QualType DestTy) { 3907 if (Context.hasSameUnqualifiedType(SrcTy, DestTy)) 3908 return CK_NoOp; 3909 3910 if (SrcTy->hasPointerRepresentation()) { 3911 if (DestTy->hasPointerRepresentation()) 3912 return DestTy->isObjCObjectPointerType() ? 3913 CK_AnyPointerToObjCPointerCast : 3914 CK_BitCast; 3915 if (DestTy->isIntegerType()) 3916 return CK_PointerToIntegral; 3917 } 3918 3919 if (SrcTy->isIntegerType()) { 3920 if (DestTy->isIntegerType()) 3921 return CK_IntegralCast; 3922 if (DestTy->hasPointerRepresentation()) 3923 return CK_IntegralToPointer; 3924 if (DestTy->isRealFloatingType()) 3925 return CK_IntegralToFloating; 3926 } 3927 3928 if (SrcTy->isRealFloatingType()) { 3929 if (DestTy->isRealFloatingType()) 3930 return CK_FloatingCast; 3931 if (DestTy->isIntegerType()) 3932 return CK_FloatingToIntegral; 3933 } 3934 3935 // FIXME: Assert here. 3936 // assert(false && "Unhandled cast combination!"); 3937 return CK_Unknown; 3938} 3939 3940/// CheckCastTypes - Check type constraints for casting between types. 3941bool Sema::CheckCastTypes(SourceRange TyR, QualType castType, Expr *&castExpr, 3942 CastKind& Kind, 3943 CXXCastPath &BasePath, 3944 bool FunctionalStyle) { 3945 if (getLangOptions().CPlusPlus) 3946 return CXXCheckCStyleCast(TyR, castType, castExpr, Kind, BasePath, 3947 FunctionalStyle); 3948 3949 DefaultFunctionArrayLvalueConversion(castExpr); 3950 3951 // C99 6.5.4p2: the cast type needs to be void or scalar and the expression 3952 // type needs to be scalar. 3953 if (castType->isVoidType()) { 3954 // Cast to void allows any expr type. 3955 Kind = CK_ToVoid; 3956 return false; 3957 } 3958 3959 if (RequireCompleteType(TyR.getBegin(), castType, 3960 diag::err_typecheck_cast_to_incomplete)) 3961 return true; 3962 3963 if (!castType->isScalarType() && !castType->isVectorType()) { 3964 if (Context.hasSameUnqualifiedType(castType, castExpr->getType()) && 3965 (castType->isStructureType() || castType->isUnionType())) { 3966 // GCC struct/union extension: allow cast to self. 3967 // FIXME: Check that the cast destination type is complete. 3968 Diag(TyR.getBegin(), diag::ext_typecheck_cast_nonscalar) 3969 << castType << castExpr->getSourceRange(); 3970 Kind = CK_NoOp; 3971 return false; 3972 } 3973 3974 if (castType->isUnionType()) { 3975 // GCC cast to union extension 3976 RecordDecl *RD = castType->getAs<RecordType>()->getDecl(); 3977 RecordDecl::field_iterator Field, FieldEnd; 3978 for (Field = RD->field_begin(), FieldEnd = RD->field_end(); 3979 Field != FieldEnd; ++Field) { 3980 if (Context.hasSameUnqualifiedType(Field->getType(), 3981 castExpr->getType())) { 3982 Diag(TyR.getBegin(), diag::ext_typecheck_cast_to_union) 3983 << castExpr->getSourceRange(); 3984 break; 3985 } 3986 } 3987 if (Field == FieldEnd) 3988 return Diag(TyR.getBegin(), diag::err_typecheck_cast_to_union_no_type) 3989 << castExpr->getType() << castExpr->getSourceRange(); 3990 Kind = CK_ToUnion; 3991 return false; 3992 } 3993 3994 // Reject any other conversions to non-scalar types. 3995 return Diag(TyR.getBegin(), diag::err_typecheck_cond_expect_scalar) 3996 << castType << castExpr->getSourceRange(); 3997 } 3998 3999 if (!castExpr->getType()->isScalarType() && 4000 !castExpr->getType()->isVectorType()) { 4001 return Diag(castExpr->getLocStart(), 4002 diag::err_typecheck_expect_scalar_operand) 4003 << castExpr->getType() << castExpr->getSourceRange(); 4004 } 4005 4006 if (castType->isExtVectorType()) 4007 return CheckExtVectorCast(TyR, castType, castExpr, Kind); 4008 4009 if (castType->isVectorType()) 4010 return CheckVectorCast(TyR, castType, castExpr->getType(), Kind); 4011 if (castExpr->getType()->isVectorType()) 4012 return CheckVectorCast(TyR, castExpr->getType(), castType, Kind); 4013 4014 if (isa<ObjCSelectorExpr>(castExpr)) 4015 return Diag(castExpr->getLocStart(), diag::err_cast_selector_expr); 4016 4017 if (!castType->isArithmeticType()) { 4018 QualType castExprType = castExpr->getType(); 4019 if (!castExprType->isIntegralType(Context) && 4020 castExprType->isArithmeticType()) 4021 return Diag(castExpr->getLocStart(), 4022 diag::err_cast_pointer_from_non_pointer_int) 4023 << castExprType << castExpr->getSourceRange(); 4024 } else if (!castExpr->getType()->isArithmeticType()) { 4025 if (!castType->isIntegralType(Context) && castType->isArithmeticType()) 4026 return Diag(castExpr->getLocStart(), 4027 diag::err_cast_pointer_to_non_pointer_int) 4028 << castType << castExpr->getSourceRange(); 4029 } 4030 4031 Kind = getScalarCastKind(Context, castExpr->getType(), castType); 4032 4033 if (Kind == CK_Unknown || Kind == CK_BitCast) 4034 CheckCastAlign(castExpr, castType, TyR); 4035 4036 return false; 4037} 4038 4039bool Sema::CheckVectorCast(SourceRange R, QualType VectorTy, QualType Ty, 4040 CastKind &Kind) { 4041 assert(VectorTy->isVectorType() && "Not a vector type!"); 4042 4043 if (Ty->isVectorType() || Ty->isIntegerType()) { 4044 if (Context.getTypeSize(VectorTy) != Context.getTypeSize(Ty)) 4045 return Diag(R.getBegin(), 4046 Ty->isVectorType() ? 4047 diag::err_invalid_conversion_between_vectors : 4048 diag::err_invalid_conversion_between_vector_and_integer) 4049 << VectorTy << Ty << R; 4050 } else 4051 return Diag(R.getBegin(), 4052 diag::err_invalid_conversion_between_vector_and_scalar) 4053 << VectorTy << Ty << R; 4054 4055 Kind = CK_BitCast; 4056 return false; 4057} 4058 4059bool Sema::CheckExtVectorCast(SourceRange R, QualType DestTy, Expr *&CastExpr, 4060 CastKind &Kind) { 4061 assert(DestTy->isExtVectorType() && "Not an extended vector type!"); 4062 4063 QualType SrcTy = CastExpr->getType(); 4064 4065 // If SrcTy is a VectorType, the total size must match to explicitly cast to 4066 // an ExtVectorType. 4067 if (SrcTy->isVectorType()) { 4068 if (Context.getTypeSize(DestTy) != Context.getTypeSize(SrcTy)) 4069 return Diag(R.getBegin(),diag::err_invalid_conversion_between_ext_vectors) 4070 << DestTy << SrcTy << R; 4071 Kind = CK_BitCast; 4072 return false; 4073 } 4074 4075 // All non-pointer scalars can be cast to ExtVector type. The appropriate 4076 // conversion will take place first from scalar to elt type, and then 4077 // splat from elt type to vector. 4078 if (SrcTy->isPointerType()) 4079 return Diag(R.getBegin(), 4080 diag::err_invalid_conversion_between_vector_and_scalar) 4081 << DestTy << SrcTy << R; 4082 4083 QualType DestElemTy = DestTy->getAs<ExtVectorType>()->getElementType(); 4084 ImpCastExprToType(CastExpr, DestElemTy, 4085 getScalarCastKind(Context, SrcTy, DestElemTy)); 4086 4087 Kind = CK_VectorSplat; 4088 return false; 4089} 4090 4091ExprResult 4092Sema::ActOnCastExpr(Scope *S, SourceLocation LParenLoc, ParsedType Ty, 4093 SourceLocation RParenLoc, Expr *castExpr) { 4094 assert((Ty != 0) && (castExpr != 0) && 4095 "ActOnCastExpr(): missing type or expr"); 4096 4097 TypeSourceInfo *castTInfo; 4098 QualType castType = GetTypeFromParser(Ty, &castTInfo); 4099 if (!castTInfo) 4100 castTInfo = Context.getTrivialTypeSourceInfo(castType); 4101 4102 // If the Expr being casted is a ParenListExpr, handle it specially. 4103 if (isa<ParenListExpr>(castExpr)) 4104 return ActOnCastOfParenListExpr(S, LParenLoc, RParenLoc, castExpr, 4105 castTInfo); 4106 4107 return BuildCStyleCastExpr(LParenLoc, castTInfo, RParenLoc, castExpr); 4108} 4109 4110ExprResult 4111Sema::BuildCStyleCastExpr(SourceLocation LParenLoc, TypeSourceInfo *Ty, 4112 SourceLocation RParenLoc, Expr *castExpr) { 4113 CastKind Kind = CK_Unknown; 4114 CXXCastPath BasePath; 4115 if (CheckCastTypes(SourceRange(LParenLoc, RParenLoc), Ty->getType(), castExpr, 4116 Kind, BasePath)) 4117 return ExprError(); 4118 4119 return Owned(CStyleCastExpr::Create(Context, 4120 Ty->getType().getNonLValueExprType(Context), 4121 Kind, castExpr, &BasePath, Ty, 4122 LParenLoc, RParenLoc)); 4123} 4124 4125/// This is not an AltiVec-style cast, so turn the ParenListExpr into a sequence 4126/// of comma binary operators. 4127ExprResult 4128Sema::MaybeConvertParenListExprToParenExpr(Scope *S, Expr *expr) { 4129 ParenListExpr *E = dyn_cast<ParenListExpr>(expr); 4130 if (!E) 4131 return Owned(expr); 4132 4133 ExprResult Result(E->getExpr(0)); 4134 4135 for (unsigned i = 1, e = E->getNumExprs(); i != e && !Result.isInvalid(); ++i) 4136 Result = ActOnBinOp(S, E->getExprLoc(), tok::comma, Result.get(), 4137 E->getExpr(i)); 4138 4139 if (Result.isInvalid()) return ExprError(); 4140 4141 return ActOnParenExpr(E->getLParenLoc(), E->getRParenLoc(), Result.get()); 4142} 4143 4144ExprResult 4145Sema::ActOnCastOfParenListExpr(Scope *S, SourceLocation LParenLoc, 4146 SourceLocation RParenLoc, Expr *Op, 4147 TypeSourceInfo *TInfo) { 4148 ParenListExpr *PE = cast<ParenListExpr>(Op); 4149 QualType Ty = TInfo->getType(); 4150 bool isAltiVecLiteral = false; 4151 4152 // Check for an altivec literal, 4153 // i.e. all the elements are integer constants. 4154 if (getLangOptions().AltiVec && Ty->isVectorType()) { 4155 if (PE->getNumExprs() == 0) { 4156 Diag(PE->getExprLoc(), diag::err_altivec_empty_initializer); 4157 return ExprError(); 4158 } 4159 if (PE->getNumExprs() == 1) { 4160 if (!PE->getExpr(0)->getType()->isVectorType()) 4161 isAltiVecLiteral = true; 4162 } 4163 else 4164 isAltiVecLiteral = true; 4165 } 4166 4167 // If this is an altivec initializer, '(' type ')' '(' init, ..., init ')' 4168 // then handle it as such. 4169 if (isAltiVecLiteral) { 4170 llvm::SmallVector<Expr *, 8> initExprs; 4171 for (unsigned i = 0, e = PE->getNumExprs(); i != e; ++i) 4172 initExprs.push_back(PE->getExpr(i)); 4173 4174 // FIXME: This means that pretty-printing the final AST will produce curly 4175 // braces instead of the original commas. 4176 InitListExpr *E = new (Context) InitListExpr(Context, LParenLoc, 4177 &initExprs[0], 4178 initExprs.size(), RParenLoc); 4179 E->setType(Ty); 4180 return BuildCompoundLiteralExpr(LParenLoc, TInfo, RParenLoc, E); 4181 } else { 4182 // This is not an AltiVec-style cast, so turn the ParenListExpr into a 4183 // sequence of BinOp comma operators. 4184 ExprResult Result = MaybeConvertParenListExprToParenExpr(S, Op); 4185 if (Result.isInvalid()) return ExprError(); 4186 return BuildCStyleCastExpr(LParenLoc, TInfo, RParenLoc, Result.take()); 4187 } 4188} 4189 4190ExprResult Sema::ActOnParenOrParenListExpr(SourceLocation L, 4191 SourceLocation R, 4192 MultiExprArg Val, 4193 ParsedType TypeOfCast) { 4194 unsigned nexprs = Val.size(); 4195 Expr **exprs = reinterpret_cast<Expr**>(Val.release()); 4196 assert((exprs != 0) && "ActOnParenOrParenListExpr() missing expr list"); 4197 Expr *expr; 4198 if (nexprs == 1 && TypeOfCast && !TypeIsVectorType(TypeOfCast)) 4199 expr = new (Context) ParenExpr(L, R, exprs[0]); 4200 else 4201 expr = new (Context) ParenListExpr(Context, L, exprs, nexprs, R); 4202 return Owned(expr); 4203} 4204 4205/// Note that lhs is not null here, even if this is the gnu "x ?: y" extension. 4206/// In that case, lhs = cond. 4207/// C99 6.5.15 4208QualType Sema::CheckConditionalOperands(Expr *&Cond, Expr *&LHS, Expr *&RHS, 4209 Expr *&SAVE, 4210 SourceLocation QuestionLoc) { 4211 // C++ is sufficiently different to merit its own checker. 4212 if (getLangOptions().CPlusPlus) 4213 return CXXCheckConditionalOperands(Cond, LHS, RHS, SAVE, QuestionLoc); 4214 4215 UsualUnaryConversions(Cond); 4216 if (SAVE) { 4217 SAVE = LHS = Cond; 4218 } 4219 else 4220 UsualUnaryConversions(LHS); 4221 UsualUnaryConversions(RHS); 4222 QualType CondTy = Cond->getType(); 4223 QualType LHSTy = LHS->getType(); 4224 QualType RHSTy = RHS->getType(); 4225 4226 // first, check the condition. 4227 if (!CondTy->isScalarType()) { // C99 6.5.15p2 4228 // OpenCL: Sec 6.3.i says the condition is allowed to be a vector or scalar. 4229 // Throw an error if its not either. 4230 if (getLangOptions().OpenCL) { 4231 if (!CondTy->isVectorType()) { 4232 Diag(Cond->getLocStart(), 4233 diag::err_typecheck_cond_expect_scalar_or_vector) 4234 << CondTy; 4235 return QualType(); 4236 } 4237 } 4238 else { 4239 Diag(Cond->getLocStart(), diag::err_typecheck_cond_expect_scalar) 4240 << CondTy; 4241 return QualType(); 4242 } 4243 } 4244 4245 // Now check the two expressions. 4246 if (LHSTy->isVectorType() || RHSTy->isVectorType()) 4247 return CheckVectorOperands(QuestionLoc, LHS, RHS); 4248 4249 // OpenCL: If the condition is a vector, and both operands are scalar, 4250 // attempt to implicity convert them to the vector type to act like the 4251 // built in select. 4252 if (getLangOptions().OpenCL && CondTy->isVectorType()) { 4253 // Both operands should be of scalar type. 4254 if (!LHSTy->isScalarType()) { 4255 Diag(LHS->getLocStart(), diag::err_typecheck_cond_expect_scalar) 4256 << CondTy; 4257 return QualType(); 4258 } 4259 if (!RHSTy->isScalarType()) { 4260 Diag(RHS->getLocStart(), diag::err_typecheck_cond_expect_scalar) 4261 << CondTy; 4262 return QualType(); 4263 } 4264 // Implicity convert these scalars to the type of the condition. 4265 ImpCastExprToType(LHS, CondTy, CK_IntegralCast); 4266 ImpCastExprToType(RHS, CondTy, CK_IntegralCast); 4267 } 4268 4269 // If both operands have arithmetic type, do the usual arithmetic conversions 4270 // to find a common type: C99 6.5.15p3,5. 4271 if (LHSTy->isArithmeticType() && RHSTy->isArithmeticType()) { 4272 UsualArithmeticConversions(LHS, RHS); 4273 return LHS->getType(); 4274 } 4275 4276 // If both operands are the same structure or union type, the result is that 4277 // type. 4278 if (const RecordType *LHSRT = LHSTy->getAs<RecordType>()) { // C99 6.5.15p3 4279 if (const RecordType *RHSRT = RHSTy->getAs<RecordType>()) 4280 if (LHSRT->getDecl() == RHSRT->getDecl()) 4281 // "If both the operands have structure or union type, the result has 4282 // that type." This implies that CV qualifiers are dropped. 4283 return LHSTy.getUnqualifiedType(); 4284 // FIXME: Type of conditional expression must be complete in C mode. 4285 } 4286 4287 // C99 6.5.15p5: "If both operands have void type, the result has void type." 4288 // The following || allows only one side to be void (a GCC-ism). 4289 if (LHSTy->isVoidType() || RHSTy->isVoidType()) { 4290 if (!LHSTy->isVoidType()) 4291 Diag(RHS->getLocStart(), diag::ext_typecheck_cond_one_void) 4292 << RHS->getSourceRange(); 4293 if (!RHSTy->isVoidType()) 4294 Diag(LHS->getLocStart(), diag::ext_typecheck_cond_one_void) 4295 << LHS->getSourceRange(); 4296 ImpCastExprToType(LHS, Context.VoidTy, CK_ToVoid); 4297 ImpCastExprToType(RHS, Context.VoidTy, CK_ToVoid); 4298 return Context.VoidTy; 4299 } 4300 // C99 6.5.15p6 - "if one operand is a null pointer constant, the result has 4301 // the type of the other operand." 4302 if ((LHSTy->isAnyPointerType() || LHSTy->isBlockPointerType()) && 4303 RHS->isNullPointerConstant(Context, Expr::NPC_ValueDependentIsNull)) { 4304 // promote the null to a pointer. 4305 ImpCastExprToType(RHS, LHSTy, CK_Unknown); 4306 return LHSTy; 4307 } 4308 if ((RHSTy->isAnyPointerType() || RHSTy->isBlockPointerType()) && 4309 LHS->isNullPointerConstant(Context, Expr::NPC_ValueDependentIsNull)) { 4310 ImpCastExprToType(LHS, RHSTy, CK_Unknown); 4311 return RHSTy; 4312 } 4313 4314 // All objective-c pointer type analysis is done here. 4315 QualType compositeType = FindCompositeObjCPointerType(LHS, RHS, 4316 QuestionLoc); 4317 if (!compositeType.isNull()) 4318 return compositeType; 4319 4320 4321 // Handle block pointer types. 4322 if (LHSTy->isBlockPointerType() || RHSTy->isBlockPointerType()) { 4323 if (!LHSTy->isBlockPointerType() || !RHSTy->isBlockPointerType()) { 4324 if (LHSTy->isVoidPointerType() || RHSTy->isVoidPointerType()) { 4325 QualType destType = Context.getPointerType(Context.VoidTy); 4326 ImpCastExprToType(LHS, destType, CK_BitCast); 4327 ImpCastExprToType(RHS, destType, CK_BitCast); 4328 return destType; 4329 } 4330 Diag(QuestionLoc, diag::err_typecheck_cond_incompatible_operands) 4331 << LHSTy << RHSTy << LHS->getSourceRange() << RHS->getSourceRange(); 4332 return QualType(); 4333 } 4334 // We have 2 block pointer types. 4335 if (Context.getCanonicalType(LHSTy) == Context.getCanonicalType(RHSTy)) { 4336 // Two identical block pointer types are always compatible. 4337 return LHSTy; 4338 } 4339 // The block pointer types aren't identical, continue checking. 4340 QualType lhptee = LHSTy->getAs<BlockPointerType>()->getPointeeType(); 4341 QualType rhptee = RHSTy->getAs<BlockPointerType>()->getPointeeType(); 4342 4343 if (!Context.typesAreCompatible(lhptee.getUnqualifiedType(), 4344 rhptee.getUnqualifiedType())) { 4345 Diag(QuestionLoc, diag::warn_typecheck_cond_incompatible_pointers) 4346 << LHSTy << RHSTy << LHS->getSourceRange() << RHS->getSourceRange(); 4347 // In this situation, we assume void* type. No especially good 4348 // reason, but this is what gcc does, and we do have to pick 4349 // to get a consistent AST. 4350 QualType incompatTy = Context.getPointerType(Context.VoidTy); 4351 ImpCastExprToType(LHS, incompatTy, CK_BitCast); 4352 ImpCastExprToType(RHS, incompatTy, CK_BitCast); 4353 return incompatTy; 4354 } 4355 // The block pointer types are compatible. 4356 ImpCastExprToType(LHS, LHSTy, CK_BitCast); 4357 ImpCastExprToType(RHS, LHSTy, CK_BitCast); 4358 return LHSTy; 4359 } 4360 4361 // Check constraints for C object pointers types (C99 6.5.15p3,6). 4362 if (LHSTy->isPointerType() && RHSTy->isPointerType()) { 4363 // get the "pointed to" types 4364 QualType lhptee = LHSTy->getAs<PointerType>()->getPointeeType(); 4365 QualType rhptee = RHSTy->getAs<PointerType>()->getPointeeType(); 4366 4367 // ignore qualifiers on void (C99 6.5.15p3, clause 6) 4368 if (lhptee->isVoidType() && rhptee->isIncompleteOrObjectType()) { 4369 // Figure out necessary qualifiers (C99 6.5.15p6) 4370 QualType destPointee 4371 = Context.getQualifiedType(lhptee, rhptee.getQualifiers()); 4372 QualType destType = Context.getPointerType(destPointee); 4373 // Add qualifiers if necessary. 4374 ImpCastExprToType(LHS, destType, CK_NoOp); 4375 // Promote to void*. 4376 ImpCastExprToType(RHS, destType, CK_BitCast); 4377 return destType; 4378 } 4379 if (rhptee->isVoidType() && lhptee->isIncompleteOrObjectType()) { 4380 QualType destPointee 4381 = Context.getQualifiedType(rhptee, lhptee.getQualifiers()); 4382 QualType destType = Context.getPointerType(destPointee); 4383 // Add qualifiers if necessary. 4384 ImpCastExprToType(RHS, destType, CK_NoOp); 4385 // Promote to void*. 4386 ImpCastExprToType(LHS, destType, CK_BitCast); 4387 return destType; 4388 } 4389 4390 if (Context.getCanonicalType(LHSTy) == Context.getCanonicalType(RHSTy)) { 4391 // Two identical pointer types are always compatible. 4392 return LHSTy; 4393 } 4394 if (!Context.typesAreCompatible(lhptee.getUnqualifiedType(), 4395 rhptee.getUnqualifiedType())) { 4396 Diag(QuestionLoc, diag::warn_typecheck_cond_incompatible_pointers) 4397 << LHSTy << RHSTy << LHS->getSourceRange() << RHS->getSourceRange(); 4398 // In this situation, we assume void* type. No especially good 4399 // reason, but this is what gcc does, and we do have to pick 4400 // to get a consistent AST. 4401 QualType incompatTy = Context.getPointerType(Context.VoidTy); 4402 ImpCastExprToType(LHS, incompatTy, CK_BitCast); 4403 ImpCastExprToType(RHS, incompatTy, CK_BitCast); 4404 return incompatTy; 4405 } 4406 // The pointer types are compatible. 4407 // C99 6.5.15p6: If both operands are pointers to compatible types *or* to 4408 // differently qualified versions of compatible types, the result type is 4409 // a pointer to an appropriately qualified version of the *composite* 4410 // type. 4411 // FIXME: Need to calculate the composite type. 4412 // FIXME: Need to add qualifiers 4413 ImpCastExprToType(LHS, LHSTy, CK_BitCast); 4414 ImpCastExprToType(RHS, LHSTy, CK_BitCast); 4415 return LHSTy; 4416 } 4417 4418 // GCC compatibility: soften pointer/integer mismatch. 4419 if (RHSTy->isPointerType() && LHSTy->isIntegerType()) { 4420 Diag(QuestionLoc, diag::warn_typecheck_cond_pointer_integer_mismatch) 4421 << LHSTy << RHSTy << LHS->getSourceRange() << RHS->getSourceRange(); 4422 ImpCastExprToType(LHS, RHSTy, CK_IntegralToPointer); 4423 return RHSTy; 4424 } 4425 if (LHSTy->isPointerType() && RHSTy->isIntegerType()) { 4426 Diag(QuestionLoc, diag::warn_typecheck_cond_pointer_integer_mismatch) 4427 << LHSTy << RHSTy << LHS->getSourceRange() << RHS->getSourceRange(); 4428 ImpCastExprToType(RHS, LHSTy, CK_IntegralToPointer); 4429 return LHSTy; 4430 } 4431 4432 // Otherwise, the operands are not compatible. 4433 Diag(QuestionLoc, diag::err_typecheck_cond_incompatible_operands) 4434 << LHSTy << RHSTy << LHS->getSourceRange() << RHS->getSourceRange(); 4435 return QualType(); 4436} 4437 4438/// FindCompositeObjCPointerType - Helper method to find composite type of 4439/// two objective-c pointer types of the two input expressions. 4440QualType Sema::FindCompositeObjCPointerType(Expr *&LHS, Expr *&RHS, 4441 SourceLocation QuestionLoc) { 4442 QualType LHSTy = LHS->getType(); 4443 QualType RHSTy = RHS->getType(); 4444 4445 // Handle things like Class and struct objc_class*. Here we case the result 4446 // to the pseudo-builtin, because that will be implicitly cast back to the 4447 // redefinition type if an attempt is made to access its fields. 4448 if (LHSTy->isObjCClassType() && 4449 (RHSTy.getDesugaredType() == Context.ObjCClassRedefinitionType)) { 4450 ImpCastExprToType(RHS, LHSTy, CK_BitCast); 4451 return LHSTy; 4452 } 4453 if (RHSTy->isObjCClassType() && 4454 (LHSTy.getDesugaredType() == Context.ObjCClassRedefinitionType)) { 4455 ImpCastExprToType(LHS, RHSTy, CK_BitCast); 4456 return RHSTy; 4457 } 4458 // And the same for struct objc_object* / id 4459 if (LHSTy->isObjCIdType() && 4460 (RHSTy.getDesugaredType() == Context.ObjCIdRedefinitionType)) { 4461 ImpCastExprToType(RHS, LHSTy, CK_BitCast); 4462 return LHSTy; 4463 } 4464 if (RHSTy->isObjCIdType() && 4465 (LHSTy.getDesugaredType() == Context.ObjCIdRedefinitionType)) { 4466 ImpCastExprToType(LHS, RHSTy, CK_BitCast); 4467 return RHSTy; 4468 } 4469 // And the same for struct objc_selector* / SEL 4470 if (Context.isObjCSelType(LHSTy) && 4471 (RHSTy.getDesugaredType() == Context.ObjCSelRedefinitionType)) { 4472 ImpCastExprToType(RHS, LHSTy, CK_BitCast); 4473 return LHSTy; 4474 } 4475 if (Context.isObjCSelType(RHSTy) && 4476 (LHSTy.getDesugaredType() == Context.ObjCSelRedefinitionType)) { 4477 ImpCastExprToType(LHS, RHSTy, CK_BitCast); 4478 return RHSTy; 4479 } 4480 // Check constraints for Objective-C object pointers types. 4481 if (LHSTy->isObjCObjectPointerType() && RHSTy->isObjCObjectPointerType()) { 4482 4483 if (Context.getCanonicalType(LHSTy) == Context.getCanonicalType(RHSTy)) { 4484 // Two identical object pointer types are always compatible. 4485 return LHSTy; 4486 } 4487 const ObjCObjectPointerType *LHSOPT = LHSTy->getAs<ObjCObjectPointerType>(); 4488 const ObjCObjectPointerType *RHSOPT = RHSTy->getAs<ObjCObjectPointerType>(); 4489 QualType compositeType = LHSTy; 4490 4491 // If both operands are interfaces and either operand can be 4492 // assigned to the other, use that type as the composite 4493 // type. This allows 4494 // xxx ? (A*) a : (B*) b 4495 // where B is a subclass of A. 4496 // 4497 // Additionally, as for assignment, if either type is 'id' 4498 // allow silent coercion. Finally, if the types are 4499 // incompatible then make sure to use 'id' as the composite 4500 // type so the result is acceptable for sending messages to. 4501 4502 // FIXME: Consider unifying with 'areComparableObjCPointerTypes'. 4503 // It could return the composite type. 4504 if (Context.canAssignObjCInterfaces(LHSOPT, RHSOPT)) { 4505 compositeType = RHSOPT->isObjCBuiltinType() ? RHSTy : LHSTy; 4506 } else if (Context.canAssignObjCInterfaces(RHSOPT, LHSOPT)) { 4507 compositeType = LHSOPT->isObjCBuiltinType() ? LHSTy : RHSTy; 4508 } else if ((LHSTy->isObjCQualifiedIdType() || 4509 RHSTy->isObjCQualifiedIdType()) && 4510 Context.ObjCQualifiedIdTypesAreCompatible(LHSTy, RHSTy, true)) { 4511 // Need to handle "id<xx>" explicitly. 4512 // GCC allows qualified id and any Objective-C type to devolve to 4513 // id. Currently localizing to here until clear this should be 4514 // part of ObjCQualifiedIdTypesAreCompatible. 4515 compositeType = Context.getObjCIdType(); 4516 } else if (LHSTy->isObjCIdType() || RHSTy->isObjCIdType()) { 4517 compositeType = Context.getObjCIdType(); 4518 } else if (!(compositeType = 4519 Context.areCommonBaseCompatible(LHSOPT, RHSOPT)).isNull()) 4520 ; 4521 else { 4522 Diag(QuestionLoc, diag::ext_typecheck_cond_incompatible_operands) 4523 << LHSTy << RHSTy 4524 << LHS->getSourceRange() << RHS->getSourceRange(); 4525 QualType incompatTy = Context.getObjCIdType(); 4526 ImpCastExprToType(LHS, incompatTy, CK_BitCast); 4527 ImpCastExprToType(RHS, incompatTy, CK_BitCast); 4528 return incompatTy; 4529 } 4530 // The object pointer types are compatible. 4531 ImpCastExprToType(LHS, compositeType, CK_BitCast); 4532 ImpCastExprToType(RHS, compositeType, CK_BitCast); 4533 return compositeType; 4534 } 4535 // Check Objective-C object pointer types and 'void *' 4536 if (LHSTy->isVoidPointerType() && RHSTy->isObjCObjectPointerType()) { 4537 QualType lhptee = LHSTy->getAs<PointerType>()->getPointeeType(); 4538 QualType rhptee = RHSTy->getAs<ObjCObjectPointerType>()->getPointeeType(); 4539 QualType destPointee 4540 = Context.getQualifiedType(lhptee, rhptee.getQualifiers()); 4541 QualType destType = Context.getPointerType(destPointee); 4542 // Add qualifiers if necessary. 4543 ImpCastExprToType(LHS, destType, CK_NoOp); 4544 // Promote to void*. 4545 ImpCastExprToType(RHS, destType, CK_BitCast); 4546 return destType; 4547 } 4548 if (LHSTy->isObjCObjectPointerType() && RHSTy->isVoidPointerType()) { 4549 QualType lhptee = LHSTy->getAs<ObjCObjectPointerType>()->getPointeeType(); 4550 QualType rhptee = RHSTy->getAs<PointerType>()->getPointeeType(); 4551 QualType destPointee 4552 = Context.getQualifiedType(rhptee, lhptee.getQualifiers()); 4553 QualType destType = Context.getPointerType(destPointee); 4554 // Add qualifiers if necessary. 4555 ImpCastExprToType(RHS, destType, CK_NoOp); 4556 // Promote to void*. 4557 ImpCastExprToType(LHS, destType, CK_BitCast); 4558 return destType; 4559 } 4560 return QualType(); 4561} 4562 4563/// ActOnConditionalOp - Parse a ?: operation. Note that 'LHS' may be null 4564/// in the case of a the GNU conditional expr extension. 4565ExprResult Sema::ActOnConditionalOp(SourceLocation QuestionLoc, 4566 SourceLocation ColonLoc, 4567 Expr *CondExpr, Expr *LHSExpr, 4568 Expr *RHSExpr) { 4569 // If this is the gnu "x ?: y" extension, analyze the types as though the LHS 4570 // was the condition. 4571 bool isLHSNull = LHSExpr == 0; 4572 Expr *SAVEExpr = 0; 4573 if (isLHSNull) { 4574 LHSExpr = SAVEExpr = CondExpr; 4575 } 4576 4577 QualType result = CheckConditionalOperands(CondExpr, LHSExpr, RHSExpr, 4578 SAVEExpr, QuestionLoc); 4579 if (result.isNull()) 4580 return ExprError(); 4581 4582 return Owned(new (Context) ConditionalOperator(CondExpr, QuestionLoc, 4583 LHSExpr, ColonLoc, 4584 RHSExpr, SAVEExpr, 4585 result)); 4586} 4587 4588// CheckPointerTypesForAssignment - This is a very tricky routine (despite 4589// being closely modeled after the C99 spec:-). The odd characteristic of this 4590// routine is it effectively iqnores the qualifiers on the top level pointee. 4591// This circumvents the usual type rules specified in 6.2.7p1 & 6.7.5.[1-3]. 4592// FIXME: add a couple examples in this comment. 4593Sema::AssignConvertType 4594Sema::CheckPointerTypesForAssignment(QualType lhsType, QualType rhsType) { 4595 QualType lhptee, rhptee; 4596 4597 if ((lhsType->isObjCClassType() && 4598 (rhsType.getDesugaredType() == Context.ObjCClassRedefinitionType)) || 4599 (rhsType->isObjCClassType() && 4600 (lhsType.getDesugaredType() == Context.ObjCClassRedefinitionType))) { 4601 return Compatible; 4602 } 4603 4604 // get the "pointed to" type (ignoring qualifiers at the top level) 4605 lhptee = lhsType->getAs<PointerType>()->getPointeeType(); 4606 rhptee = rhsType->getAs<PointerType>()->getPointeeType(); 4607 4608 // make sure we operate on the canonical type 4609 lhptee = Context.getCanonicalType(lhptee); 4610 rhptee = Context.getCanonicalType(rhptee); 4611 4612 AssignConvertType ConvTy = Compatible; 4613 4614 // C99 6.5.16.1p1: This following citation is common to constraints 4615 // 3 & 4 (below). ...and the type *pointed to* by the left has all the 4616 // qualifiers of the type *pointed to* by the right; 4617 // FIXME: Handle ExtQualType 4618 if (!lhptee.isAtLeastAsQualifiedAs(rhptee)) 4619 ConvTy = CompatiblePointerDiscardsQualifiers; 4620 4621 // C99 6.5.16.1p1 (constraint 4): If one operand is a pointer to an object or 4622 // incomplete type and the other is a pointer to a qualified or unqualified 4623 // version of void... 4624 if (lhptee->isVoidType()) { 4625 if (rhptee->isIncompleteOrObjectType()) 4626 return ConvTy; 4627 4628 // As an extension, we allow cast to/from void* to function pointer. 4629 assert(rhptee->isFunctionType()); 4630 return FunctionVoidPointer; 4631 } 4632 4633 if (rhptee->isVoidType()) { 4634 if (lhptee->isIncompleteOrObjectType()) 4635 return ConvTy; 4636 4637 // As an extension, we allow cast to/from void* to function pointer. 4638 assert(lhptee->isFunctionType()); 4639 return FunctionVoidPointer; 4640 } 4641 // C99 6.5.16.1p1 (constraint 3): both operands are pointers to qualified or 4642 // unqualified versions of compatible types, ... 4643 lhptee = lhptee.getUnqualifiedType(); 4644 rhptee = rhptee.getUnqualifiedType(); 4645 if (!Context.typesAreCompatible(lhptee, rhptee)) { 4646 // Check if the pointee types are compatible ignoring the sign. 4647 // We explicitly check for char so that we catch "char" vs 4648 // "unsigned char" on systems where "char" is unsigned. 4649 if (lhptee->isCharType()) 4650 lhptee = Context.UnsignedCharTy; 4651 else if (lhptee->hasSignedIntegerRepresentation()) 4652 lhptee = Context.getCorrespondingUnsignedType(lhptee); 4653 4654 if (rhptee->isCharType()) 4655 rhptee = Context.UnsignedCharTy; 4656 else if (rhptee->hasSignedIntegerRepresentation()) 4657 rhptee = Context.getCorrespondingUnsignedType(rhptee); 4658 4659 if (lhptee == rhptee) { 4660 // Types are compatible ignoring the sign. Qualifier incompatibility 4661 // takes priority over sign incompatibility because the sign 4662 // warning can be disabled. 4663 if (ConvTy != Compatible) 4664 return ConvTy; 4665 return IncompatiblePointerSign; 4666 } 4667 4668 // If we are a multi-level pointer, it's possible that our issue is simply 4669 // one of qualification - e.g. char ** -> const char ** is not allowed. If 4670 // the eventual target type is the same and the pointers have the same 4671 // level of indirection, this must be the issue. 4672 if (lhptee->isPointerType() && rhptee->isPointerType()) { 4673 do { 4674 lhptee = lhptee->getAs<PointerType>()->getPointeeType(); 4675 rhptee = rhptee->getAs<PointerType>()->getPointeeType(); 4676 4677 lhptee = Context.getCanonicalType(lhptee); 4678 rhptee = Context.getCanonicalType(rhptee); 4679 } while (lhptee->isPointerType() && rhptee->isPointerType()); 4680 4681 if (Context.hasSameUnqualifiedType(lhptee, rhptee)) 4682 return IncompatibleNestedPointerQualifiers; 4683 } 4684 4685 // General pointer incompatibility takes priority over qualifiers. 4686 return IncompatiblePointer; 4687 } 4688 return ConvTy; 4689} 4690 4691/// CheckBlockPointerTypesForAssignment - This routine determines whether two 4692/// block pointer types are compatible or whether a block and normal pointer 4693/// are compatible. It is more restrict than comparing two function pointer 4694// types. 4695Sema::AssignConvertType 4696Sema::CheckBlockPointerTypesForAssignment(QualType lhsType, 4697 QualType rhsType) { 4698 QualType lhptee, rhptee; 4699 4700 // get the "pointed to" type (ignoring qualifiers at the top level) 4701 lhptee = lhsType->getAs<BlockPointerType>()->getPointeeType(); 4702 rhptee = rhsType->getAs<BlockPointerType>()->getPointeeType(); 4703 4704 // make sure we operate on the canonical type 4705 lhptee = Context.getCanonicalType(lhptee); 4706 rhptee = Context.getCanonicalType(rhptee); 4707 4708 AssignConvertType ConvTy = Compatible; 4709 4710 // For blocks we enforce that qualifiers are identical. 4711 if (lhptee.getLocalCVRQualifiers() != rhptee.getLocalCVRQualifiers()) 4712 ConvTy = CompatiblePointerDiscardsQualifiers; 4713 4714 if (!getLangOptions().CPlusPlus) { 4715 if (!Context.typesAreBlockPointerCompatible(lhsType, rhsType)) 4716 return IncompatibleBlockPointer; 4717 } 4718 else if (!Context.typesAreCompatible(lhptee, rhptee)) 4719 return IncompatibleBlockPointer; 4720 return ConvTy; 4721} 4722 4723/// CheckObjCPointerTypesForAssignment - Compares two objective-c pointer types 4724/// for assignment compatibility. 4725Sema::AssignConvertType 4726Sema::CheckObjCPointerTypesForAssignment(QualType lhsType, QualType rhsType) { 4727 if (lhsType->isObjCBuiltinType()) { 4728 // Class is not compatible with ObjC object pointers. 4729 if (lhsType->isObjCClassType() && !rhsType->isObjCBuiltinType() && 4730 !rhsType->isObjCQualifiedClassType()) 4731 return IncompatiblePointer; 4732 return Compatible; 4733 } 4734 if (rhsType->isObjCBuiltinType()) { 4735 // Class is not compatible with ObjC object pointers. 4736 if (rhsType->isObjCClassType() && !lhsType->isObjCBuiltinType() && 4737 !lhsType->isObjCQualifiedClassType()) 4738 return IncompatiblePointer; 4739 return Compatible; 4740 } 4741 QualType lhptee = 4742 lhsType->getAs<ObjCObjectPointerType>()->getPointeeType(); 4743 QualType rhptee = 4744 rhsType->getAs<ObjCObjectPointerType>()->getPointeeType(); 4745 // make sure we operate on the canonical type 4746 lhptee = Context.getCanonicalType(lhptee); 4747 rhptee = Context.getCanonicalType(rhptee); 4748 if (!lhptee.isAtLeastAsQualifiedAs(rhptee)) 4749 return CompatiblePointerDiscardsQualifiers; 4750 4751 if (Context.typesAreCompatible(lhsType, rhsType)) 4752 return Compatible; 4753 if (lhsType->isObjCQualifiedIdType() || rhsType->isObjCQualifiedIdType()) 4754 return IncompatibleObjCQualifiedId; 4755 return IncompatiblePointer; 4756} 4757 4758/// CheckAssignmentConstraints (C99 6.5.16) - This routine currently 4759/// has code to accommodate several GCC extensions when type checking 4760/// pointers. Here are some objectionable examples that GCC considers warnings: 4761/// 4762/// int a, *pint; 4763/// short *pshort; 4764/// struct foo *pfoo; 4765/// 4766/// pint = pshort; // warning: assignment from incompatible pointer type 4767/// a = pint; // warning: assignment makes integer from pointer without a cast 4768/// pint = a; // warning: assignment makes pointer from integer without a cast 4769/// pint = pfoo; // warning: assignment from incompatible pointer type 4770/// 4771/// As a result, the code for dealing with pointers is more complex than the 4772/// C99 spec dictates. 4773/// 4774Sema::AssignConvertType 4775Sema::CheckAssignmentConstraints(QualType lhsType, QualType rhsType) { 4776 // Get canonical types. We're not formatting these types, just comparing 4777 // them. 4778 lhsType = Context.getCanonicalType(lhsType).getUnqualifiedType(); 4779 rhsType = Context.getCanonicalType(rhsType).getUnqualifiedType(); 4780 4781 if (lhsType == rhsType) 4782 return Compatible; // Common case: fast path an exact match. 4783 4784 if ((lhsType->isObjCClassType() && 4785 (rhsType.getDesugaredType() == Context.ObjCClassRedefinitionType)) || 4786 (rhsType->isObjCClassType() && 4787 (lhsType.getDesugaredType() == Context.ObjCClassRedefinitionType))) { 4788 return Compatible; 4789 } 4790 4791 // If the left-hand side is a reference type, then we are in a 4792 // (rare!) case where we've allowed the use of references in C, 4793 // e.g., as a parameter type in a built-in function. In this case, 4794 // just make sure that the type referenced is compatible with the 4795 // right-hand side type. The caller is responsible for adjusting 4796 // lhsType so that the resulting expression does not have reference 4797 // type. 4798 if (const ReferenceType *lhsTypeRef = lhsType->getAs<ReferenceType>()) { 4799 if (Context.typesAreCompatible(lhsTypeRef->getPointeeType(), rhsType)) 4800 return Compatible; 4801 return Incompatible; 4802 } 4803 // Allow scalar to ExtVector assignments, and assignments of an ExtVector type 4804 // to the same ExtVector type. 4805 if (lhsType->isExtVectorType()) { 4806 if (rhsType->isExtVectorType()) 4807 return lhsType == rhsType ? Compatible : Incompatible; 4808 if (rhsType->isArithmeticType()) 4809 return Compatible; 4810 } 4811 4812 if (lhsType->isVectorType() || rhsType->isVectorType()) { 4813 if (lhsType->isVectorType() && rhsType->isVectorType()) { 4814 // If we are allowing lax vector conversions, and LHS and RHS are both 4815 // vectors, the total size only needs to be the same. This is a bitcast; 4816 // no bits are changed but the result type is different. 4817 if (getLangOptions().LaxVectorConversions && 4818 (Context.getTypeSize(lhsType) == Context.getTypeSize(rhsType))) 4819 return IncompatibleVectors; 4820 4821 // Allow assignments of an AltiVec vector type to an equivalent GCC 4822 // vector type and vice versa 4823 if (Context.areCompatibleVectorTypes(lhsType, rhsType)) 4824 return Compatible; 4825 } 4826 return Incompatible; 4827 } 4828 4829 if (lhsType->isArithmeticType() && rhsType->isArithmeticType() && 4830 !(getLangOptions().CPlusPlus && lhsType->isEnumeralType())) 4831 return Compatible; 4832 4833 if (isa<PointerType>(lhsType)) { 4834 if (rhsType->isIntegerType()) 4835 return IntToPointer; 4836 4837 if (isa<PointerType>(rhsType)) 4838 return CheckPointerTypesForAssignment(lhsType, rhsType); 4839 4840 // In general, C pointers are not compatible with ObjC object pointers. 4841 if (isa<ObjCObjectPointerType>(rhsType)) { 4842 if (lhsType->isVoidPointerType()) // an exception to the rule. 4843 return Compatible; 4844 return IncompatiblePointer; 4845 } 4846 if (rhsType->getAs<BlockPointerType>()) { 4847 if (lhsType->getAs<PointerType>()->getPointeeType()->isVoidType()) 4848 return Compatible; 4849 4850 // Treat block pointers as objects. 4851 if (getLangOptions().ObjC1 && lhsType->isObjCIdType()) 4852 return Compatible; 4853 } 4854 return Incompatible; 4855 } 4856 4857 if (isa<BlockPointerType>(lhsType)) { 4858 if (rhsType->isIntegerType()) 4859 return IntToBlockPointer; 4860 4861 // Treat block pointers as objects. 4862 if (getLangOptions().ObjC1 && rhsType->isObjCIdType()) 4863 return Compatible; 4864 4865 if (rhsType->isBlockPointerType()) 4866 return CheckBlockPointerTypesForAssignment(lhsType, rhsType); 4867 4868 if (const PointerType *RHSPT = rhsType->getAs<PointerType>()) { 4869 if (RHSPT->getPointeeType()->isVoidType()) 4870 return Compatible; 4871 } 4872 return Incompatible; 4873 } 4874 4875 if (isa<ObjCObjectPointerType>(lhsType)) { 4876 if (rhsType->isIntegerType()) 4877 return IntToPointer; 4878 4879 // In general, C pointers are not compatible with ObjC object pointers. 4880 if (isa<PointerType>(rhsType)) { 4881 if (rhsType->isVoidPointerType()) // an exception to the rule. 4882 return Compatible; 4883 return IncompatiblePointer; 4884 } 4885 if (rhsType->isObjCObjectPointerType()) { 4886 return CheckObjCPointerTypesForAssignment(lhsType, rhsType); 4887 } 4888 if (const PointerType *RHSPT = rhsType->getAs<PointerType>()) { 4889 if (RHSPT->getPointeeType()->isVoidType()) 4890 return Compatible; 4891 } 4892 // Treat block pointers as objects. 4893 if (rhsType->isBlockPointerType()) 4894 return Compatible; 4895 return Incompatible; 4896 } 4897 if (isa<PointerType>(rhsType)) { 4898 // C99 6.5.16.1p1: the left operand is _Bool and the right is a pointer. 4899 if (lhsType == Context.BoolTy) 4900 return Compatible; 4901 4902 if (lhsType->isIntegerType()) 4903 return PointerToInt; 4904 4905 if (isa<PointerType>(lhsType)) 4906 return CheckPointerTypesForAssignment(lhsType, rhsType); 4907 4908 if (isa<BlockPointerType>(lhsType) && 4909 rhsType->getAs<PointerType>()->getPointeeType()->isVoidType()) 4910 return Compatible; 4911 return Incompatible; 4912 } 4913 if (isa<ObjCObjectPointerType>(rhsType)) { 4914 // C99 6.5.16.1p1: the left operand is _Bool and the right is a pointer. 4915 if (lhsType == Context.BoolTy) 4916 return Compatible; 4917 4918 if (lhsType->isIntegerType()) 4919 return PointerToInt; 4920 4921 // In general, C pointers are not compatible with ObjC object pointers. 4922 if (isa<PointerType>(lhsType)) { 4923 if (lhsType->isVoidPointerType()) // an exception to the rule. 4924 return Compatible; 4925 return IncompatiblePointer; 4926 } 4927 if (isa<BlockPointerType>(lhsType) && 4928 rhsType->getAs<PointerType>()->getPointeeType()->isVoidType()) 4929 return Compatible; 4930 return Incompatible; 4931 } 4932 4933 if (isa<TagType>(lhsType) && isa<TagType>(rhsType)) { 4934 if (Context.typesAreCompatible(lhsType, rhsType)) 4935 return Compatible; 4936 } 4937 return Incompatible; 4938} 4939 4940/// \brief Constructs a transparent union from an expression that is 4941/// used to initialize the transparent union. 4942static void ConstructTransparentUnion(ASTContext &C, Expr *&E, 4943 QualType UnionType, FieldDecl *Field) { 4944 // Build an initializer list that designates the appropriate member 4945 // of the transparent union. 4946 InitListExpr *Initializer = new (C) InitListExpr(C, SourceLocation(), 4947 &E, 1, 4948 SourceLocation()); 4949 Initializer->setType(UnionType); 4950 Initializer->setInitializedFieldInUnion(Field); 4951 4952 // Build a compound literal constructing a value of the transparent 4953 // union type from this initializer list. 4954 TypeSourceInfo *unionTInfo = C.getTrivialTypeSourceInfo(UnionType); 4955 E = new (C) CompoundLiteralExpr(SourceLocation(), unionTInfo, UnionType, 4956 Initializer, false); 4957} 4958 4959Sema::AssignConvertType 4960Sema::CheckTransparentUnionArgumentConstraints(QualType ArgType, Expr *&rExpr) { 4961 QualType FromType = rExpr->getType(); 4962 4963 // If the ArgType is a Union type, we want to handle a potential 4964 // transparent_union GCC extension. 4965 const RecordType *UT = ArgType->getAsUnionType(); 4966 if (!UT || !UT->getDecl()->hasAttr<TransparentUnionAttr>()) 4967 return Incompatible; 4968 4969 // The field to initialize within the transparent union. 4970 RecordDecl *UD = UT->getDecl(); 4971 FieldDecl *InitField = 0; 4972 // It's compatible if the expression matches any of the fields. 4973 for (RecordDecl::field_iterator it = UD->field_begin(), 4974 itend = UD->field_end(); 4975 it != itend; ++it) { 4976 if (it->getType()->isPointerType()) { 4977 // If the transparent union contains a pointer type, we allow: 4978 // 1) void pointer 4979 // 2) null pointer constant 4980 if (FromType->isPointerType()) 4981 if (FromType->getAs<PointerType>()->getPointeeType()->isVoidType()) { 4982 ImpCastExprToType(rExpr, it->getType(), CK_BitCast); 4983 InitField = *it; 4984 break; 4985 } 4986 4987 if (rExpr->isNullPointerConstant(Context, 4988 Expr::NPC_ValueDependentIsNull)) { 4989 ImpCastExprToType(rExpr, it->getType(), CK_IntegralToPointer); 4990 InitField = *it; 4991 break; 4992 } 4993 } 4994 4995 if (CheckAssignmentConstraints(it->getType(), rExpr->getType()) 4996 == Compatible) { 4997 ImpCastExprToType(rExpr, it->getType(), CK_Unknown); 4998 InitField = *it; 4999 break; 5000 } 5001 } 5002 5003 if (!InitField) 5004 return Incompatible; 5005 5006 ConstructTransparentUnion(Context, rExpr, ArgType, InitField); 5007 return Compatible; 5008} 5009 5010Sema::AssignConvertType 5011Sema::CheckSingleAssignmentConstraints(QualType lhsType, Expr *&rExpr) { 5012 if (getLangOptions().CPlusPlus) { 5013 if (!lhsType->isRecordType()) { 5014 // C++ 5.17p3: If the left operand is not of class type, the 5015 // expression is implicitly converted (C++ 4) to the 5016 // cv-unqualified type of the left operand. 5017 if (PerformImplicitConversion(rExpr, lhsType.getUnqualifiedType(), 5018 AA_Assigning)) 5019 return Incompatible; 5020 return Compatible; 5021 } 5022 5023 // FIXME: Currently, we fall through and treat C++ classes like C 5024 // structures. 5025 } 5026 5027 // C99 6.5.16.1p1: the left operand is a pointer and the right is 5028 // a null pointer constant. 5029 if ((lhsType->isPointerType() || 5030 lhsType->isObjCObjectPointerType() || 5031 lhsType->isBlockPointerType()) 5032 && rExpr->isNullPointerConstant(Context, 5033 Expr::NPC_ValueDependentIsNull)) { 5034 ImpCastExprToType(rExpr, lhsType, CK_Unknown); 5035 return Compatible; 5036 } 5037 5038 // This check seems unnatural, however it is necessary to ensure the proper 5039 // conversion of functions/arrays. If the conversion were done for all 5040 // DeclExpr's (created by ActOnIdExpression), it would mess up the unary 5041 // expressions that suppress this implicit conversion (&, sizeof). 5042 // 5043 // Suppress this for references: C++ 8.5.3p5. 5044 if (!lhsType->isReferenceType()) 5045 DefaultFunctionArrayLvalueConversion(rExpr); 5046 5047 Sema::AssignConvertType result = 5048 CheckAssignmentConstraints(lhsType, rExpr->getType()); 5049 5050 // C99 6.5.16.1p2: The value of the right operand is converted to the 5051 // type of the assignment expression. 5052 // CheckAssignmentConstraints allows the left-hand side to be a reference, 5053 // so that we can use references in built-in functions even in C. 5054 // The getNonReferenceType() call makes sure that the resulting expression 5055 // does not have reference type. 5056 if (result != Incompatible && rExpr->getType() != lhsType) 5057 ImpCastExprToType(rExpr, lhsType.getNonLValueExprType(Context), 5058 CK_Unknown); 5059 return result; 5060} 5061 5062QualType Sema::InvalidOperands(SourceLocation Loc, Expr *&lex, Expr *&rex) { 5063 Diag(Loc, diag::err_typecheck_invalid_operands) 5064 << lex->getType() << rex->getType() 5065 << lex->getSourceRange() << rex->getSourceRange(); 5066 return QualType(); 5067} 5068 5069QualType Sema::CheckVectorOperands(SourceLocation Loc, Expr *&lex, Expr *&rex) { 5070 // For conversion purposes, we ignore any qualifiers. 5071 // For example, "const float" and "float" are equivalent. 5072 QualType lhsType = 5073 Context.getCanonicalType(lex->getType()).getUnqualifiedType(); 5074 QualType rhsType = 5075 Context.getCanonicalType(rex->getType()).getUnqualifiedType(); 5076 5077 // If the vector types are identical, return. 5078 if (lhsType == rhsType) 5079 return lhsType; 5080 5081 // Handle the case of a vector & extvector type of the same size and element 5082 // type. It would be nice if we only had one vector type someday. 5083 if (getLangOptions().LaxVectorConversions) { 5084 if (const VectorType *LV = lhsType->getAs<VectorType>()) { 5085 if (const VectorType *RV = rhsType->getAs<VectorType>()) { 5086 if (LV->getElementType() == RV->getElementType() && 5087 LV->getNumElements() == RV->getNumElements()) { 5088 if (lhsType->isExtVectorType()) { 5089 ImpCastExprToType(rex, lhsType, CK_BitCast); 5090 return lhsType; 5091 } 5092 5093 ImpCastExprToType(lex, rhsType, CK_BitCast); 5094 return rhsType; 5095 } else if (Context.getTypeSize(lhsType) ==Context.getTypeSize(rhsType)){ 5096 // If we are allowing lax vector conversions, and LHS and RHS are both 5097 // vectors, the total size only needs to be the same. This is a 5098 // bitcast; no bits are changed but the result type is different. 5099 ImpCastExprToType(rex, lhsType, CK_BitCast); 5100 return lhsType; 5101 } 5102 } 5103 } 5104 } 5105 5106 // Handle the case of equivalent AltiVec and GCC vector types 5107 if (lhsType->isVectorType() && rhsType->isVectorType() && 5108 Context.areCompatibleVectorTypes(lhsType, rhsType)) { 5109 ImpCastExprToType(lex, rhsType, CK_BitCast); 5110 return rhsType; 5111 } 5112 5113 // Canonicalize the ExtVector to the LHS, remember if we swapped so we can 5114 // swap back (so that we don't reverse the inputs to a subtract, for instance. 5115 bool swapped = false; 5116 if (rhsType->isExtVectorType()) { 5117 swapped = true; 5118 std::swap(rex, lex); 5119 std::swap(rhsType, lhsType); 5120 } 5121 5122 // Handle the case of an ext vector and scalar. 5123 if (const ExtVectorType *LV = lhsType->getAs<ExtVectorType>()) { 5124 QualType EltTy = LV->getElementType(); 5125 if (EltTy->isIntegralType(Context) && rhsType->isIntegralType(Context)) { 5126 if (Context.getIntegerTypeOrder(EltTy, rhsType) >= 0) { 5127 ImpCastExprToType(rex, lhsType, CK_IntegralCast); 5128 if (swapped) std::swap(rex, lex); 5129 return lhsType; 5130 } 5131 } 5132 if (EltTy->isRealFloatingType() && rhsType->isScalarType() && 5133 rhsType->isRealFloatingType()) { 5134 if (Context.getFloatingTypeOrder(EltTy, rhsType) >= 0) { 5135 ImpCastExprToType(rex, lhsType, CK_FloatingCast); 5136 if (swapped) std::swap(rex, lex); 5137 return lhsType; 5138 } 5139 } 5140 } 5141 5142 // Vectors of different size or scalar and non-ext-vector are errors. 5143 Diag(Loc, diag::err_typecheck_vector_not_convertable) 5144 << lex->getType() << rex->getType() 5145 << lex->getSourceRange() << rex->getSourceRange(); 5146 return QualType(); 5147} 5148 5149QualType Sema::CheckMultiplyDivideOperands( 5150 Expr *&lex, Expr *&rex, SourceLocation Loc, bool isCompAssign, bool isDiv) { 5151 if (lex->getType()->isVectorType() || rex->getType()->isVectorType()) 5152 return CheckVectorOperands(Loc, lex, rex); 5153 5154 QualType compType = UsualArithmeticConversions(lex, rex, isCompAssign); 5155 5156 if (!lex->getType()->isArithmeticType() || 5157 !rex->getType()->isArithmeticType()) 5158 return InvalidOperands(Loc, lex, rex); 5159 5160 // Check for division by zero. 5161 if (isDiv && 5162 rex->isNullPointerConstant(Context, Expr::NPC_ValueDependentIsNotNull)) 5163 DiagRuntimeBehavior(Loc, PDiag(diag::warn_division_by_zero) 5164 << rex->getSourceRange()); 5165 5166 return compType; 5167} 5168 5169QualType Sema::CheckRemainderOperands( 5170 Expr *&lex, Expr *&rex, SourceLocation Loc, bool isCompAssign) { 5171 if (lex->getType()->isVectorType() || rex->getType()->isVectorType()) { 5172 if (lex->getType()->hasIntegerRepresentation() && 5173 rex->getType()->hasIntegerRepresentation()) 5174 return CheckVectorOperands(Loc, lex, rex); 5175 return InvalidOperands(Loc, lex, rex); 5176 } 5177 5178 QualType compType = UsualArithmeticConversions(lex, rex, isCompAssign); 5179 5180 if (!lex->getType()->isIntegerType() || !rex->getType()->isIntegerType()) 5181 return InvalidOperands(Loc, lex, rex); 5182 5183 // Check for remainder by zero. 5184 if (rex->isNullPointerConstant(Context, Expr::NPC_ValueDependentIsNotNull)) 5185 DiagRuntimeBehavior(Loc, PDiag(diag::warn_remainder_by_zero) 5186 << rex->getSourceRange()); 5187 5188 return compType; 5189} 5190 5191QualType Sema::CheckAdditionOperands( // C99 6.5.6 5192 Expr *&lex, Expr *&rex, SourceLocation Loc, QualType* CompLHSTy) { 5193 if (lex->getType()->isVectorType() || rex->getType()->isVectorType()) { 5194 QualType compType = CheckVectorOperands(Loc, lex, rex); 5195 if (CompLHSTy) *CompLHSTy = compType; 5196 return compType; 5197 } 5198 5199 QualType compType = UsualArithmeticConversions(lex, rex, CompLHSTy); 5200 5201 // handle the common case first (both operands are arithmetic). 5202 if (lex->getType()->isArithmeticType() && 5203 rex->getType()->isArithmeticType()) { 5204 if (CompLHSTy) *CompLHSTy = compType; 5205 return compType; 5206 } 5207 5208 // Put any potential pointer into PExp 5209 Expr* PExp = lex, *IExp = rex; 5210 if (IExp->getType()->isAnyPointerType()) 5211 std::swap(PExp, IExp); 5212 5213 if (PExp->getType()->isAnyPointerType()) { 5214 5215 if (IExp->getType()->isIntegerType()) { 5216 QualType PointeeTy = PExp->getType()->getPointeeType(); 5217 5218 // Check for arithmetic on pointers to incomplete types. 5219 if (PointeeTy->isVoidType()) { 5220 if (getLangOptions().CPlusPlus) { 5221 Diag(Loc, diag::err_typecheck_pointer_arith_void_type) 5222 << lex->getSourceRange() << rex->getSourceRange(); 5223 return QualType(); 5224 } 5225 5226 // GNU extension: arithmetic on pointer to void 5227 Diag(Loc, diag::ext_gnu_void_ptr) 5228 << lex->getSourceRange() << rex->getSourceRange(); 5229 } else if (PointeeTy->isFunctionType()) { 5230 if (getLangOptions().CPlusPlus) { 5231 Diag(Loc, diag::err_typecheck_pointer_arith_function_type) 5232 << lex->getType() << lex->getSourceRange(); 5233 return QualType(); 5234 } 5235 5236 // GNU extension: arithmetic on pointer to function 5237 Diag(Loc, diag::ext_gnu_ptr_func_arith) 5238 << lex->getType() << lex->getSourceRange(); 5239 } else { 5240 // Check if we require a complete type. 5241 if (((PExp->getType()->isPointerType() && 5242 !PExp->getType()->isDependentType()) || 5243 PExp->getType()->isObjCObjectPointerType()) && 5244 RequireCompleteType(Loc, PointeeTy, 5245 PDiag(diag::err_typecheck_arithmetic_incomplete_type) 5246 << PExp->getSourceRange() 5247 << PExp->getType())) 5248 return QualType(); 5249 } 5250 // Diagnose bad cases where we step over interface counts. 5251 if (PointeeTy->isObjCObjectType() && LangOpts.ObjCNonFragileABI) { 5252 Diag(Loc, diag::err_arithmetic_nonfragile_interface) 5253 << PointeeTy << PExp->getSourceRange(); 5254 return QualType(); 5255 } 5256 5257 if (CompLHSTy) { 5258 QualType LHSTy = Context.isPromotableBitField(lex); 5259 if (LHSTy.isNull()) { 5260 LHSTy = lex->getType(); 5261 if (LHSTy->isPromotableIntegerType()) 5262 LHSTy = Context.getPromotedIntegerType(LHSTy); 5263 } 5264 *CompLHSTy = LHSTy; 5265 } 5266 return PExp->getType(); 5267 } 5268 } 5269 5270 return InvalidOperands(Loc, lex, rex); 5271} 5272 5273// C99 6.5.6 5274QualType Sema::CheckSubtractionOperands(Expr *&lex, Expr *&rex, 5275 SourceLocation Loc, QualType* CompLHSTy) { 5276 if (lex->getType()->isVectorType() || rex->getType()->isVectorType()) { 5277 QualType compType = CheckVectorOperands(Loc, lex, rex); 5278 if (CompLHSTy) *CompLHSTy = compType; 5279 return compType; 5280 } 5281 5282 QualType compType = UsualArithmeticConversions(lex, rex, CompLHSTy); 5283 5284 // Enforce type constraints: C99 6.5.6p3. 5285 5286 // Handle the common case first (both operands are arithmetic). 5287 if (lex->getType()->isArithmeticType() 5288 && rex->getType()->isArithmeticType()) { 5289 if (CompLHSTy) *CompLHSTy = compType; 5290 return compType; 5291 } 5292 5293 // Either ptr - int or ptr - ptr. 5294 if (lex->getType()->isAnyPointerType()) { 5295 QualType lpointee = lex->getType()->getPointeeType(); 5296 5297 // The LHS must be an completely-defined object type. 5298 5299 bool ComplainAboutVoid = false; 5300 Expr *ComplainAboutFunc = 0; 5301 if (lpointee->isVoidType()) { 5302 if (getLangOptions().CPlusPlus) { 5303 Diag(Loc, diag::err_typecheck_pointer_arith_void_type) 5304 << lex->getSourceRange() << rex->getSourceRange(); 5305 return QualType(); 5306 } 5307 5308 // GNU C extension: arithmetic on pointer to void 5309 ComplainAboutVoid = true; 5310 } else if (lpointee->isFunctionType()) { 5311 if (getLangOptions().CPlusPlus) { 5312 Diag(Loc, diag::err_typecheck_pointer_arith_function_type) 5313 << lex->getType() << lex->getSourceRange(); 5314 return QualType(); 5315 } 5316 5317 // GNU C extension: arithmetic on pointer to function 5318 ComplainAboutFunc = lex; 5319 } else if (!lpointee->isDependentType() && 5320 RequireCompleteType(Loc, lpointee, 5321 PDiag(diag::err_typecheck_sub_ptr_object) 5322 << lex->getSourceRange() 5323 << lex->getType())) 5324 return QualType(); 5325 5326 // Diagnose bad cases where we step over interface counts. 5327 if (lpointee->isObjCObjectType() && LangOpts.ObjCNonFragileABI) { 5328 Diag(Loc, diag::err_arithmetic_nonfragile_interface) 5329 << lpointee << lex->getSourceRange(); 5330 return QualType(); 5331 } 5332 5333 // The result type of a pointer-int computation is the pointer type. 5334 if (rex->getType()->isIntegerType()) { 5335 if (ComplainAboutVoid) 5336 Diag(Loc, diag::ext_gnu_void_ptr) 5337 << lex->getSourceRange() << rex->getSourceRange(); 5338 if (ComplainAboutFunc) 5339 Diag(Loc, diag::ext_gnu_ptr_func_arith) 5340 << ComplainAboutFunc->getType() 5341 << ComplainAboutFunc->getSourceRange(); 5342 5343 if (CompLHSTy) *CompLHSTy = lex->getType(); 5344 return lex->getType(); 5345 } 5346 5347 // Handle pointer-pointer subtractions. 5348 if (const PointerType *RHSPTy = rex->getType()->getAs<PointerType>()) { 5349 QualType rpointee = RHSPTy->getPointeeType(); 5350 5351 // RHS must be a completely-type object type. 5352 // Handle the GNU void* extension. 5353 if (rpointee->isVoidType()) { 5354 if (getLangOptions().CPlusPlus) { 5355 Diag(Loc, diag::err_typecheck_pointer_arith_void_type) 5356 << lex->getSourceRange() << rex->getSourceRange(); 5357 return QualType(); 5358 } 5359 5360 ComplainAboutVoid = true; 5361 } else if (rpointee->isFunctionType()) { 5362 if (getLangOptions().CPlusPlus) { 5363 Diag(Loc, diag::err_typecheck_pointer_arith_function_type) 5364 << rex->getType() << rex->getSourceRange(); 5365 return QualType(); 5366 } 5367 5368 // GNU extension: arithmetic on pointer to function 5369 if (!ComplainAboutFunc) 5370 ComplainAboutFunc = rex; 5371 } else if (!rpointee->isDependentType() && 5372 RequireCompleteType(Loc, rpointee, 5373 PDiag(diag::err_typecheck_sub_ptr_object) 5374 << rex->getSourceRange() 5375 << rex->getType())) 5376 return QualType(); 5377 5378 if (getLangOptions().CPlusPlus) { 5379 // Pointee types must be the same: C++ [expr.add] 5380 if (!Context.hasSameUnqualifiedType(lpointee, rpointee)) { 5381 Diag(Loc, diag::err_typecheck_sub_ptr_compatible) 5382 << lex->getType() << rex->getType() 5383 << lex->getSourceRange() << rex->getSourceRange(); 5384 return QualType(); 5385 } 5386 } else { 5387 // Pointee types must be compatible C99 6.5.6p3 5388 if (!Context.typesAreCompatible( 5389 Context.getCanonicalType(lpointee).getUnqualifiedType(), 5390 Context.getCanonicalType(rpointee).getUnqualifiedType())) { 5391 Diag(Loc, diag::err_typecheck_sub_ptr_compatible) 5392 << lex->getType() << rex->getType() 5393 << lex->getSourceRange() << rex->getSourceRange(); 5394 return QualType(); 5395 } 5396 } 5397 5398 if (ComplainAboutVoid) 5399 Diag(Loc, diag::ext_gnu_void_ptr) 5400 << lex->getSourceRange() << rex->getSourceRange(); 5401 if (ComplainAboutFunc) 5402 Diag(Loc, diag::ext_gnu_ptr_func_arith) 5403 << ComplainAboutFunc->getType() 5404 << ComplainAboutFunc->getSourceRange(); 5405 5406 if (CompLHSTy) *CompLHSTy = lex->getType(); 5407 return Context.getPointerDiffType(); 5408 } 5409 } 5410 5411 return InvalidOperands(Loc, lex, rex); 5412} 5413 5414// C99 6.5.7 5415QualType Sema::CheckShiftOperands(Expr *&lex, Expr *&rex, SourceLocation Loc, 5416 bool isCompAssign) { 5417 // C99 6.5.7p2: Each of the operands shall have integer type. 5418 if (!lex->getType()->hasIntegerRepresentation() || 5419 !rex->getType()->hasIntegerRepresentation()) 5420 return InvalidOperands(Loc, lex, rex); 5421 5422 // Vector shifts promote their scalar inputs to vector type. 5423 if (lex->getType()->isVectorType() || rex->getType()->isVectorType()) 5424 return CheckVectorOperands(Loc, lex, rex); 5425 5426 // Shifts don't perform usual arithmetic conversions, they just do integer 5427 // promotions on each operand. C99 6.5.7p3 5428 QualType LHSTy = Context.isPromotableBitField(lex); 5429 if (LHSTy.isNull()) { 5430 LHSTy = lex->getType(); 5431 if (LHSTy->isPromotableIntegerType()) 5432 LHSTy = Context.getPromotedIntegerType(LHSTy); 5433 } 5434 if (!isCompAssign) 5435 ImpCastExprToType(lex, LHSTy, CK_IntegralCast); 5436 5437 UsualUnaryConversions(rex); 5438 5439 // Sanity-check shift operands 5440 llvm::APSInt Right; 5441 // Check right/shifter operand 5442 if (!rex->isValueDependent() && 5443 rex->isIntegerConstantExpr(Right, Context)) { 5444 if (Right.isNegative()) 5445 Diag(Loc, diag::warn_shift_negative) << rex->getSourceRange(); 5446 else { 5447 llvm::APInt LeftBits(Right.getBitWidth(), 5448 Context.getTypeSize(lex->getType())); 5449 if (Right.uge(LeftBits)) 5450 Diag(Loc, diag::warn_shift_gt_typewidth) << rex->getSourceRange(); 5451 } 5452 } 5453 5454 // "The type of the result is that of the promoted left operand." 5455 return LHSTy; 5456} 5457 5458static bool IsWithinTemplateSpecialization(Decl *D) { 5459 if (DeclContext *DC = D->getDeclContext()) { 5460 if (isa<ClassTemplateSpecializationDecl>(DC)) 5461 return true; 5462 if (FunctionDecl *FD = dyn_cast<FunctionDecl>(DC)) 5463 return FD->isFunctionTemplateSpecialization(); 5464 } 5465 return false; 5466} 5467 5468// C99 6.5.8, C++ [expr.rel] 5469QualType Sema::CheckCompareOperands(Expr *&lex, Expr *&rex, SourceLocation Loc, 5470 unsigned OpaqueOpc, bool isRelational) { 5471 BinaryOperatorKind Opc = (BinaryOperatorKind) OpaqueOpc; 5472 5473 // Handle vector comparisons separately. 5474 if (lex->getType()->isVectorType() || rex->getType()->isVectorType()) 5475 return CheckVectorCompareOperands(lex, rex, Loc, isRelational); 5476 5477 QualType lType = lex->getType(); 5478 QualType rType = rex->getType(); 5479 5480 if (!lType->hasFloatingRepresentation() && 5481 !(lType->isBlockPointerType() && isRelational) && 5482 !lex->getLocStart().isMacroID() && 5483 !rex->getLocStart().isMacroID()) { 5484 // For non-floating point types, check for self-comparisons of the form 5485 // x == x, x != x, x < x, etc. These always evaluate to a constant, and 5486 // often indicate logic errors in the program. 5487 // 5488 // NOTE: Don't warn about comparison expressions resulting from macro 5489 // expansion. Also don't warn about comparisons which are only self 5490 // comparisons within a template specialization. The warnings should catch 5491 // obvious cases in the definition of the template anyways. The idea is to 5492 // warn when the typed comparison operator will always evaluate to the same 5493 // result. 5494 Expr *LHSStripped = lex->IgnoreParens(); 5495 Expr *RHSStripped = rex->IgnoreParens(); 5496 if (DeclRefExpr* DRL = dyn_cast<DeclRefExpr>(LHSStripped)) { 5497 if (DeclRefExpr* DRR = dyn_cast<DeclRefExpr>(RHSStripped)) { 5498 if (DRL->getDecl() == DRR->getDecl() && 5499 !IsWithinTemplateSpecialization(DRL->getDecl())) { 5500 DiagRuntimeBehavior(Loc, PDiag(diag::warn_comparison_always) 5501 << 0 // self- 5502 << (Opc == BO_EQ 5503 || Opc == BO_LE 5504 || Opc == BO_GE)); 5505 } else if (lType->isArrayType() && rType->isArrayType() && 5506 !DRL->getDecl()->getType()->isReferenceType() && 5507 !DRR->getDecl()->getType()->isReferenceType()) { 5508 // what is it always going to eval to? 5509 char always_evals_to; 5510 switch(Opc) { 5511 case BO_EQ: // e.g. array1 == array2 5512 always_evals_to = 0; // false 5513 break; 5514 case BO_NE: // e.g. array1 != array2 5515 always_evals_to = 1; // true 5516 break; 5517 default: 5518 // best we can say is 'a constant' 5519 always_evals_to = 2; // e.g. array1 <= array2 5520 break; 5521 } 5522 DiagRuntimeBehavior(Loc, PDiag(diag::warn_comparison_always) 5523 << 1 // array 5524 << always_evals_to); 5525 } 5526 } 5527 } 5528 5529 if (isa<CastExpr>(LHSStripped)) 5530 LHSStripped = LHSStripped->IgnoreParenCasts(); 5531 if (isa<CastExpr>(RHSStripped)) 5532 RHSStripped = RHSStripped->IgnoreParenCasts(); 5533 5534 // Warn about comparisons against a string constant (unless the other 5535 // operand is null), the user probably wants strcmp. 5536 Expr *literalString = 0; 5537 Expr *literalStringStripped = 0; 5538 if ((isa<StringLiteral>(LHSStripped) || isa<ObjCEncodeExpr>(LHSStripped)) && 5539 !RHSStripped->isNullPointerConstant(Context, 5540 Expr::NPC_ValueDependentIsNull)) { 5541 literalString = lex; 5542 literalStringStripped = LHSStripped; 5543 } else if ((isa<StringLiteral>(RHSStripped) || 5544 isa<ObjCEncodeExpr>(RHSStripped)) && 5545 !LHSStripped->isNullPointerConstant(Context, 5546 Expr::NPC_ValueDependentIsNull)) { 5547 literalString = rex; 5548 literalStringStripped = RHSStripped; 5549 } 5550 5551 if (literalString) { 5552 std::string resultComparison; 5553 switch (Opc) { 5554 case BO_LT: resultComparison = ") < 0"; break; 5555 case BO_GT: resultComparison = ") > 0"; break; 5556 case BO_LE: resultComparison = ") <= 0"; break; 5557 case BO_GE: resultComparison = ") >= 0"; break; 5558 case BO_EQ: resultComparison = ") == 0"; break; 5559 case BO_NE: resultComparison = ") != 0"; break; 5560 default: assert(false && "Invalid comparison operator"); 5561 } 5562 5563 DiagRuntimeBehavior(Loc, 5564 PDiag(diag::warn_stringcompare) 5565 << isa<ObjCEncodeExpr>(literalStringStripped) 5566 << literalString->getSourceRange()); 5567 } 5568 } 5569 5570 // C99 6.5.8p3 / C99 6.5.9p4 5571 if (lex->getType()->isArithmeticType() && rex->getType()->isArithmeticType()) 5572 UsualArithmeticConversions(lex, rex); 5573 else { 5574 UsualUnaryConversions(lex); 5575 UsualUnaryConversions(rex); 5576 } 5577 5578 lType = lex->getType(); 5579 rType = rex->getType(); 5580 5581 // The result of comparisons is 'bool' in C++, 'int' in C. 5582 QualType ResultTy = getLangOptions().CPlusPlus ? Context.BoolTy:Context.IntTy; 5583 5584 if (isRelational) { 5585 if (lType->isRealType() && rType->isRealType()) 5586 return ResultTy; 5587 } else { 5588 // Check for comparisons of floating point operands using != and ==. 5589 if (lType->hasFloatingRepresentation()) 5590 CheckFloatComparison(Loc,lex,rex); 5591 5592 if (lType->isArithmeticType() && rType->isArithmeticType()) 5593 return ResultTy; 5594 } 5595 5596 bool LHSIsNull = lex->isNullPointerConstant(Context, 5597 Expr::NPC_ValueDependentIsNull); 5598 bool RHSIsNull = rex->isNullPointerConstant(Context, 5599 Expr::NPC_ValueDependentIsNull); 5600 5601 // All of the following pointer-related warnings are GCC extensions, except 5602 // when handling null pointer constants. 5603 if (lType->isPointerType() && rType->isPointerType()) { // C99 6.5.8p2 5604 QualType LCanPointeeTy = 5605 Context.getCanonicalType(lType->getAs<PointerType>()->getPointeeType()); 5606 QualType RCanPointeeTy = 5607 Context.getCanonicalType(rType->getAs<PointerType>()->getPointeeType()); 5608 5609 if (getLangOptions().CPlusPlus) { 5610 if (LCanPointeeTy == RCanPointeeTy) 5611 return ResultTy; 5612 if (!isRelational && 5613 (LCanPointeeTy->isVoidType() || RCanPointeeTy->isVoidType())) { 5614 // Valid unless comparison between non-null pointer and function pointer 5615 // This is a gcc extension compatibility comparison. 5616 // In a SFINAE context, we treat this as a hard error to maintain 5617 // conformance with the C++ standard. 5618 if ((LCanPointeeTy->isFunctionType() || RCanPointeeTy->isFunctionType()) 5619 && !LHSIsNull && !RHSIsNull) { 5620 Diag(Loc, 5621 isSFINAEContext()? 5622 diag::err_typecheck_comparison_of_fptr_to_void 5623 : diag::ext_typecheck_comparison_of_fptr_to_void) 5624 << lType << rType << lex->getSourceRange() << rex->getSourceRange(); 5625 5626 if (isSFINAEContext()) 5627 return QualType(); 5628 5629 ImpCastExprToType(rex, lType, CK_BitCast); 5630 return ResultTy; 5631 } 5632 } 5633 // C++ [expr.rel]p2: 5634 // [...] Pointer conversions (4.10) and qualification 5635 // conversions (4.4) are performed on pointer operands (or on 5636 // a pointer operand and a null pointer constant) to bring 5637 // them to their composite pointer type. [...] 5638 // 5639 // C++ [expr.eq]p1 uses the same notion for (in)equality 5640 // comparisons of pointers. 5641 bool NonStandardCompositeType = false; 5642 QualType T = FindCompositePointerType(Loc, lex, rex, 5643 isSFINAEContext()? 0 : &NonStandardCompositeType); 5644 if (T.isNull()) { 5645 Diag(Loc, diag::err_typecheck_comparison_of_distinct_pointers) 5646 << lType << rType << lex->getSourceRange() << rex->getSourceRange(); 5647 return QualType(); 5648 } else if (NonStandardCompositeType) { 5649 Diag(Loc, 5650 diag::ext_typecheck_comparison_of_distinct_pointers_nonstandard) 5651 << lType << rType << T 5652 << lex->getSourceRange() << rex->getSourceRange(); 5653 } 5654 5655 ImpCastExprToType(lex, T, CK_BitCast); 5656 ImpCastExprToType(rex, T, CK_BitCast); 5657 return ResultTy; 5658 } 5659 // C99 6.5.9p2 and C99 6.5.8p2 5660 if (Context.typesAreCompatible(LCanPointeeTy.getUnqualifiedType(), 5661 RCanPointeeTy.getUnqualifiedType())) { 5662 // Valid unless a relational comparison of function pointers 5663 if (isRelational && LCanPointeeTy->isFunctionType()) { 5664 Diag(Loc, diag::ext_typecheck_ordered_comparison_of_function_pointers) 5665 << lType << rType << lex->getSourceRange() << rex->getSourceRange(); 5666 } 5667 } else if (!isRelational && 5668 (LCanPointeeTy->isVoidType() || RCanPointeeTy->isVoidType())) { 5669 // Valid unless comparison between non-null pointer and function pointer 5670 if ((LCanPointeeTy->isFunctionType() || RCanPointeeTy->isFunctionType()) 5671 && !LHSIsNull && !RHSIsNull) { 5672 Diag(Loc, diag::ext_typecheck_comparison_of_fptr_to_void) 5673 << lType << rType << lex->getSourceRange() << rex->getSourceRange(); 5674 } 5675 } else { 5676 // Invalid 5677 Diag(Loc, diag::ext_typecheck_comparison_of_distinct_pointers) 5678 << lType << rType << lex->getSourceRange() << rex->getSourceRange(); 5679 } 5680 if (LCanPointeeTy != RCanPointeeTy) 5681 ImpCastExprToType(rex, lType, CK_BitCast); 5682 return ResultTy; 5683 } 5684 5685 if (getLangOptions().CPlusPlus) { 5686 // Comparison of pointers with null pointer constants and equality 5687 // comparisons of member pointers to null pointer constants. 5688 if (RHSIsNull && 5689 (lType->isPointerType() || 5690 (!isRelational && lType->isMemberPointerType()))) { 5691 ImpCastExprToType(rex, lType, 5692 lType->isMemberPointerType() 5693 ? CK_NullToMemberPointer 5694 : CK_IntegralToPointer); 5695 return ResultTy; 5696 } 5697 if (LHSIsNull && 5698 (rType->isPointerType() || 5699 (!isRelational && rType->isMemberPointerType()))) { 5700 ImpCastExprToType(lex, rType, 5701 rType->isMemberPointerType() 5702 ? CK_NullToMemberPointer 5703 : CK_IntegralToPointer); 5704 return ResultTy; 5705 } 5706 5707 // Comparison of member pointers. 5708 if (!isRelational && 5709 lType->isMemberPointerType() && rType->isMemberPointerType()) { 5710 // C++ [expr.eq]p2: 5711 // In addition, pointers to members can be compared, or a pointer to 5712 // member and a null pointer constant. Pointer to member conversions 5713 // (4.11) and qualification conversions (4.4) are performed to bring 5714 // them to a common type. If one operand is a null pointer constant, 5715 // the common type is the type of the other operand. Otherwise, the 5716 // common type is a pointer to member type similar (4.4) to the type 5717 // of one of the operands, with a cv-qualification signature (4.4) 5718 // that is the union of the cv-qualification signatures of the operand 5719 // types. 5720 bool NonStandardCompositeType = false; 5721 QualType T = FindCompositePointerType(Loc, lex, rex, 5722 isSFINAEContext()? 0 : &NonStandardCompositeType); 5723 if (T.isNull()) { 5724 Diag(Loc, diag::err_typecheck_comparison_of_distinct_pointers) 5725 << lType << rType << lex->getSourceRange() << rex->getSourceRange(); 5726 return QualType(); 5727 } else if (NonStandardCompositeType) { 5728 Diag(Loc, 5729 diag::ext_typecheck_comparison_of_distinct_pointers_nonstandard) 5730 << lType << rType << T 5731 << lex->getSourceRange() << rex->getSourceRange(); 5732 } 5733 5734 ImpCastExprToType(lex, T, CK_BitCast); 5735 ImpCastExprToType(rex, T, CK_BitCast); 5736 return ResultTy; 5737 } 5738 5739 // Comparison of nullptr_t with itself. 5740 if (lType->isNullPtrType() && rType->isNullPtrType()) 5741 return ResultTy; 5742 } 5743 5744 // Handle block pointer types. 5745 if (!isRelational && lType->isBlockPointerType() && rType->isBlockPointerType()) { 5746 QualType lpointee = lType->getAs<BlockPointerType>()->getPointeeType(); 5747 QualType rpointee = rType->getAs<BlockPointerType>()->getPointeeType(); 5748 5749 if (!LHSIsNull && !RHSIsNull && 5750 !Context.typesAreCompatible(lpointee, rpointee)) { 5751 Diag(Loc, diag::err_typecheck_comparison_of_distinct_blocks) 5752 << lType << rType << lex->getSourceRange() << rex->getSourceRange(); 5753 } 5754 ImpCastExprToType(rex, lType, CK_BitCast); 5755 return ResultTy; 5756 } 5757 // Allow block pointers to be compared with null pointer constants. 5758 if (!isRelational 5759 && ((lType->isBlockPointerType() && rType->isPointerType()) 5760 || (lType->isPointerType() && rType->isBlockPointerType()))) { 5761 if (!LHSIsNull && !RHSIsNull) { 5762 if (!((rType->isPointerType() && rType->getAs<PointerType>() 5763 ->getPointeeType()->isVoidType()) 5764 || (lType->isPointerType() && lType->getAs<PointerType>() 5765 ->getPointeeType()->isVoidType()))) 5766 Diag(Loc, diag::err_typecheck_comparison_of_distinct_blocks) 5767 << lType << rType << lex->getSourceRange() << rex->getSourceRange(); 5768 } 5769 ImpCastExprToType(rex, lType, CK_BitCast); 5770 return ResultTy; 5771 } 5772 5773 if ((lType->isObjCObjectPointerType() || rType->isObjCObjectPointerType())) { 5774 if (lType->isPointerType() || rType->isPointerType()) { 5775 const PointerType *LPT = lType->getAs<PointerType>(); 5776 const PointerType *RPT = rType->getAs<PointerType>(); 5777 bool LPtrToVoid = LPT ? 5778 Context.getCanonicalType(LPT->getPointeeType())->isVoidType() : false; 5779 bool RPtrToVoid = RPT ? 5780 Context.getCanonicalType(RPT->getPointeeType())->isVoidType() : false; 5781 5782 if (!LPtrToVoid && !RPtrToVoid && 5783 !Context.typesAreCompatible(lType, rType)) { 5784 Diag(Loc, diag::ext_typecheck_comparison_of_distinct_pointers) 5785 << lType << rType << lex->getSourceRange() << rex->getSourceRange(); 5786 } 5787 ImpCastExprToType(rex, lType, CK_BitCast); 5788 return ResultTy; 5789 } 5790 if (lType->isObjCObjectPointerType() && rType->isObjCObjectPointerType()) { 5791 if (!Context.areComparableObjCPointerTypes(lType, rType)) 5792 Diag(Loc, diag::ext_typecheck_comparison_of_distinct_pointers) 5793 << lType << rType << lex->getSourceRange() << rex->getSourceRange(); 5794 ImpCastExprToType(rex, lType, CK_BitCast); 5795 return ResultTy; 5796 } 5797 } 5798 if ((lType->isAnyPointerType() && rType->isIntegerType()) || 5799 (lType->isIntegerType() && rType->isAnyPointerType())) { 5800 unsigned DiagID = 0; 5801 bool isError = false; 5802 if ((LHSIsNull && lType->isIntegerType()) || 5803 (RHSIsNull && rType->isIntegerType())) { 5804 if (isRelational && !getLangOptions().CPlusPlus) 5805 DiagID = diag::ext_typecheck_ordered_comparison_of_pointer_and_zero; 5806 } else if (isRelational && !getLangOptions().CPlusPlus) 5807 DiagID = diag::ext_typecheck_ordered_comparison_of_pointer_integer; 5808 else if (getLangOptions().CPlusPlus) { 5809 DiagID = diag::err_typecheck_comparison_of_pointer_integer; 5810 isError = true; 5811 } else 5812 DiagID = diag::ext_typecheck_comparison_of_pointer_integer; 5813 5814 if (DiagID) { 5815 Diag(Loc, DiagID) 5816 << lType << rType << lex->getSourceRange() << rex->getSourceRange(); 5817 if (isError) 5818 return QualType(); 5819 } 5820 5821 if (lType->isIntegerType()) 5822 ImpCastExprToType(lex, rType, CK_IntegralToPointer); 5823 else 5824 ImpCastExprToType(rex, lType, CK_IntegralToPointer); 5825 return ResultTy; 5826 } 5827 5828 // Handle block pointers. 5829 if (!isRelational && RHSIsNull 5830 && lType->isBlockPointerType() && rType->isIntegerType()) { 5831 ImpCastExprToType(rex, lType, CK_IntegralToPointer); 5832 return ResultTy; 5833 } 5834 if (!isRelational && LHSIsNull 5835 && lType->isIntegerType() && rType->isBlockPointerType()) { 5836 ImpCastExprToType(lex, rType, CK_IntegralToPointer); 5837 return ResultTy; 5838 } 5839 return InvalidOperands(Loc, lex, rex); 5840} 5841 5842/// CheckVectorCompareOperands - vector comparisons are a clang extension that 5843/// operates on extended vector types. Instead of producing an IntTy result, 5844/// like a scalar comparison, a vector comparison produces a vector of integer 5845/// types. 5846QualType Sema::CheckVectorCompareOperands(Expr *&lex, Expr *&rex, 5847 SourceLocation Loc, 5848 bool isRelational) { 5849 // Check to make sure we're operating on vectors of the same type and width, 5850 // Allowing one side to be a scalar of element type. 5851 QualType vType = CheckVectorOperands(Loc, lex, rex); 5852 if (vType.isNull()) 5853 return vType; 5854 5855 QualType lType = lex->getType(); 5856 QualType rType = rex->getType(); 5857 5858 // For non-floating point types, check for self-comparisons of the form 5859 // x == x, x != x, x < x, etc. These always evaluate to a constant, and 5860 // often indicate logic errors in the program. 5861 if (!lType->hasFloatingRepresentation()) { 5862 if (DeclRefExpr* DRL = dyn_cast<DeclRefExpr>(lex->IgnoreParens())) 5863 if (DeclRefExpr* DRR = dyn_cast<DeclRefExpr>(rex->IgnoreParens())) 5864 if (DRL->getDecl() == DRR->getDecl()) 5865 DiagRuntimeBehavior(Loc, 5866 PDiag(diag::warn_comparison_always) 5867 << 0 // self- 5868 << 2 // "a constant" 5869 ); 5870 } 5871 5872 // Check for comparisons of floating point operands using != and ==. 5873 if (!isRelational && lType->hasFloatingRepresentation()) { 5874 assert (rType->hasFloatingRepresentation()); 5875 CheckFloatComparison(Loc,lex,rex); 5876 } 5877 5878 // Return the type for the comparison, which is the same as vector type for 5879 // integer vectors, or an integer type of identical size and number of 5880 // elements for floating point vectors. 5881 if (lType->hasIntegerRepresentation()) 5882 return lType; 5883 5884 const VectorType *VTy = lType->getAs<VectorType>(); 5885 unsigned TypeSize = Context.getTypeSize(VTy->getElementType()); 5886 if (TypeSize == Context.getTypeSize(Context.IntTy)) 5887 return Context.getExtVectorType(Context.IntTy, VTy->getNumElements()); 5888 if (TypeSize == Context.getTypeSize(Context.LongTy)) 5889 return Context.getExtVectorType(Context.LongTy, VTy->getNumElements()); 5890 5891 assert(TypeSize == Context.getTypeSize(Context.LongLongTy) && 5892 "Unhandled vector element size in vector compare"); 5893 return Context.getExtVectorType(Context.LongLongTy, VTy->getNumElements()); 5894} 5895 5896inline QualType Sema::CheckBitwiseOperands( 5897 Expr *&lex, Expr *&rex, SourceLocation Loc, bool isCompAssign) { 5898 if (lex->getType()->isVectorType() || rex->getType()->isVectorType()) { 5899 if (lex->getType()->hasIntegerRepresentation() && 5900 rex->getType()->hasIntegerRepresentation()) 5901 return CheckVectorOperands(Loc, lex, rex); 5902 5903 return InvalidOperands(Loc, lex, rex); 5904 } 5905 5906 QualType compType = UsualArithmeticConversions(lex, rex, isCompAssign); 5907 5908 if (lex->getType()->isIntegerType() && rex->getType()->isIntegerType()) 5909 return compType; 5910 return InvalidOperands(Loc, lex, rex); 5911} 5912 5913inline QualType Sema::CheckLogicalOperands( // C99 6.5.[13,14] 5914 Expr *&lex, Expr *&rex, SourceLocation Loc, unsigned Opc) { 5915 5916 // Diagnose cases where the user write a logical and/or but probably meant a 5917 // bitwise one. We do this when the LHS is a non-bool integer and the RHS 5918 // is a constant. 5919 if (lex->getType()->isIntegerType() && !lex->getType()->isBooleanType() && 5920 rex->getType()->isIntegerType() && !rex->isValueDependent() && 5921 // Don't warn in macros. 5922 !Loc.isMacroID()) { 5923 // If the RHS can be constant folded, and if it constant folds to something 5924 // that isn't 0 or 1 (which indicate a potential logical operation that 5925 // happened to fold to true/false) then warn. 5926 Expr::EvalResult Result; 5927 if (rex->Evaluate(Result, Context) && !Result.HasSideEffects && 5928 Result.Val.getInt() != 0 && Result.Val.getInt() != 1) { 5929 Diag(Loc, diag::warn_logical_instead_of_bitwise) 5930 << rex->getSourceRange() 5931 << (Opc == BO_LAnd ? "&&" : "||") 5932 << (Opc == BO_LAnd ? "&" : "|"); 5933 } 5934 } 5935 5936 if (!Context.getLangOptions().CPlusPlus) { 5937 UsualUnaryConversions(lex); 5938 UsualUnaryConversions(rex); 5939 5940 if (!lex->getType()->isScalarType() || !rex->getType()->isScalarType()) 5941 return InvalidOperands(Loc, lex, rex); 5942 5943 return Context.IntTy; 5944 } 5945 5946 // The following is safe because we only use this method for 5947 // non-overloadable operands. 5948 5949 // C++ [expr.log.and]p1 5950 // C++ [expr.log.or]p1 5951 // The operands are both contextually converted to type bool. 5952 if (PerformContextuallyConvertToBool(lex) || 5953 PerformContextuallyConvertToBool(rex)) 5954 return InvalidOperands(Loc, lex, rex); 5955 5956 // C++ [expr.log.and]p2 5957 // C++ [expr.log.or]p2 5958 // The result is a bool. 5959 return Context.BoolTy; 5960} 5961 5962/// IsReadonlyProperty - Verify that otherwise a valid l-value expression 5963/// is a read-only property; return true if so. A readonly property expression 5964/// depends on various declarations and thus must be treated specially. 5965/// 5966static bool IsReadonlyProperty(Expr *E, Sema &S) { 5967 if (E->getStmtClass() == Expr::ObjCPropertyRefExprClass) { 5968 const ObjCPropertyRefExpr* PropExpr = cast<ObjCPropertyRefExpr>(E); 5969 if (ObjCPropertyDecl *PDecl = PropExpr->getProperty()) { 5970 QualType BaseType = PropExpr->getBase()->getType(); 5971 if (const ObjCObjectPointerType *OPT = 5972 BaseType->getAsObjCInterfacePointerType()) 5973 if (ObjCInterfaceDecl *IFace = OPT->getInterfaceDecl()) 5974 if (S.isPropertyReadonly(PDecl, IFace)) 5975 return true; 5976 } 5977 } 5978 return false; 5979} 5980 5981/// CheckForModifiableLvalue - Verify that E is a modifiable lvalue. If not, 5982/// emit an error and return true. If so, return false. 5983static bool CheckForModifiableLvalue(Expr *E, SourceLocation Loc, Sema &S) { 5984 SourceLocation OrigLoc = Loc; 5985 Expr::isModifiableLvalueResult IsLV = E->isModifiableLvalue(S.Context, 5986 &Loc); 5987 if (IsLV == Expr::MLV_Valid && IsReadonlyProperty(E, S)) 5988 IsLV = Expr::MLV_ReadonlyProperty; 5989 if (IsLV == Expr::MLV_Valid) 5990 return false; 5991 5992 unsigned Diag = 0; 5993 bool NeedType = false; 5994 switch (IsLV) { // C99 6.5.16p2 5995 case Expr::MLV_ConstQualified: Diag = diag::err_typecheck_assign_const; break; 5996 case Expr::MLV_ArrayType: 5997 Diag = diag::err_typecheck_array_not_modifiable_lvalue; 5998 NeedType = true; 5999 break; 6000 case Expr::MLV_NotObjectType: 6001 Diag = diag::err_typecheck_non_object_not_modifiable_lvalue; 6002 NeedType = true; 6003 break; 6004 case Expr::MLV_LValueCast: 6005 Diag = diag::err_typecheck_lvalue_casts_not_supported; 6006 break; 6007 case Expr::MLV_Valid: 6008 llvm_unreachable("did not take early return for MLV_Valid"); 6009 case Expr::MLV_InvalidExpression: 6010 case Expr::MLV_MemberFunction: 6011 case Expr::MLV_ClassTemporary: 6012 Diag = diag::err_typecheck_expression_not_modifiable_lvalue; 6013 break; 6014 case Expr::MLV_IncompleteType: 6015 case Expr::MLV_IncompleteVoidType: 6016 return S.RequireCompleteType(Loc, E->getType(), 6017 S.PDiag(diag::err_typecheck_incomplete_type_not_modifiable_lvalue) 6018 << E->getSourceRange()); 6019 case Expr::MLV_DuplicateVectorComponents: 6020 Diag = diag::err_typecheck_duplicate_vector_components_not_mlvalue; 6021 break; 6022 case Expr::MLV_NotBlockQualified: 6023 Diag = diag::err_block_decl_ref_not_modifiable_lvalue; 6024 break; 6025 case Expr::MLV_ReadonlyProperty: 6026 Diag = diag::error_readonly_property_assignment; 6027 break; 6028 case Expr::MLV_NoSetterProperty: 6029 Diag = diag::error_nosetter_property_assignment; 6030 break; 6031 case Expr::MLV_SubObjCPropertySetting: 6032 Diag = diag::error_no_subobject_property_setting; 6033 break; 6034 } 6035 6036 SourceRange Assign; 6037 if (Loc != OrigLoc) 6038 Assign = SourceRange(OrigLoc, OrigLoc); 6039 if (NeedType) 6040 S.Diag(Loc, Diag) << E->getType() << E->getSourceRange() << Assign; 6041 else 6042 S.Diag(Loc, Diag) << E->getSourceRange() << Assign; 6043 return true; 6044} 6045 6046 6047 6048// C99 6.5.16.1 6049QualType Sema::CheckAssignmentOperands(Expr *LHS, Expr *&RHS, 6050 SourceLocation Loc, 6051 QualType CompoundType) { 6052 // Verify that LHS is a modifiable lvalue, and emit error if not. 6053 if (CheckForModifiableLvalue(LHS, Loc, *this)) 6054 return QualType(); 6055 6056 QualType LHSType = LHS->getType(); 6057 QualType RHSType = CompoundType.isNull() ? RHS->getType() : CompoundType; 6058 AssignConvertType ConvTy; 6059 if (CompoundType.isNull()) { 6060 QualType LHSTy(LHSType); 6061 // Simple assignment "x = y". 6062 ConvertPropertyAssignment(LHS, RHS, LHSTy); 6063 ConvTy = CheckSingleAssignmentConstraints(LHSTy, RHS); 6064 // Special case of NSObject attributes on c-style pointer types. 6065 if (ConvTy == IncompatiblePointer && 6066 ((Context.isObjCNSObjectType(LHSType) && 6067 RHSType->isObjCObjectPointerType()) || 6068 (Context.isObjCNSObjectType(RHSType) && 6069 LHSType->isObjCObjectPointerType()))) 6070 ConvTy = Compatible; 6071 6072 // If the RHS is a unary plus or minus, check to see if they = and + are 6073 // right next to each other. If so, the user may have typo'd "x =+ 4" 6074 // instead of "x += 4". 6075 Expr *RHSCheck = RHS; 6076 if (ImplicitCastExpr *ICE = dyn_cast<ImplicitCastExpr>(RHSCheck)) 6077 RHSCheck = ICE->getSubExpr(); 6078 if (UnaryOperator *UO = dyn_cast<UnaryOperator>(RHSCheck)) { 6079 if ((UO->getOpcode() == UO_Plus || 6080 UO->getOpcode() == UO_Minus) && 6081 Loc.isFileID() && UO->getOperatorLoc().isFileID() && 6082 // Only if the two operators are exactly adjacent. 6083 Loc.getFileLocWithOffset(1) == UO->getOperatorLoc() && 6084 // And there is a space or other character before the subexpr of the 6085 // unary +/-. We don't want to warn on "x=-1". 6086 Loc.getFileLocWithOffset(2) != UO->getSubExpr()->getLocStart() && 6087 UO->getSubExpr()->getLocStart().isFileID()) { 6088 Diag(Loc, diag::warn_not_compound_assign) 6089 << (UO->getOpcode() == UO_Plus ? "+" : "-") 6090 << SourceRange(UO->getOperatorLoc(), UO->getOperatorLoc()); 6091 } 6092 } 6093 } else { 6094 // Compound assignment "x += y" 6095 ConvTy = CheckAssignmentConstraints(LHSType, RHSType); 6096 } 6097 6098 if (DiagnoseAssignmentResult(ConvTy, Loc, LHSType, RHSType, 6099 RHS, AA_Assigning)) 6100 return QualType(); 6101 6102 6103 // Check to see if the destination operand is a dereferenced null pointer. If 6104 // so, and if not volatile-qualified, this is undefined behavior that the 6105 // optimizer will delete, so warn about it. People sometimes try to use this 6106 // to get a deterministic trap and are surprised by clang's behavior. This 6107 // only handles the pattern "*null = whatever", which is a very syntactic 6108 // check. 6109 if (UnaryOperator *UO = dyn_cast<UnaryOperator>(LHS->IgnoreParenCasts())) 6110 if (UO->getOpcode() == UO_Deref && 6111 UO->getSubExpr()->IgnoreParenCasts()-> 6112 isNullPointerConstant(Context, Expr::NPC_ValueDependentIsNotNull) && 6113 !UO->getType().isVolatileQualified()) { 6114 Diag(UO->getOperatorLoc(), diag::warn_indirection_through_null) 6115 << UO->getSubExpr()->getSourceRange(); 6116 Diag(UO->getOperatorLoc(), diag::note_indirection_through_null); 6117 } 6118 6119 // C99 6.5.16p3: The type of an assignment expression is the type of the 6120 // left operand unless the left operand has qualified type, in which case 6121 // it is the unqualified version of the type of the left operand. 6122 // C99 6.5.16.1p2: In simple assignment, the value of the right operand 6123 // is converted to the type of the assignment expression (above). 6124 // C++ 5.17p1: the type of the assignment expression is that of its left 6125 // operand. 6126 return LHSType.getUnqualifiedType(); 6127} 6128 6129// C99 6.5.17 6130QualType Sema::CheckCommaOperands(Expr *LHS, Expr *&RHS, SourceLocation Loc) { 6131 DiagnoseUnusedExprResult(LHS); 6132 6133 // Comma performs lvalue conversion (C99 6.3.2.1), but not unary conversions. 6134 // C++ does not perform this conversion (C++ [expr.comma]p1). 6135 if (!getLangOptions().CPlusPlus) 6136 DefaultFunctionArrayLvalueConversion(RHS); 6137 6138 // FIXME: Check that RHS type is complete in C mode (it's legal for it to be 6139 // incomplete in C++). 6140 6141 return RHS->getType(); 6142} 6143 6144/// CheckIncrementDecrementOperand - unlike most "Check" methods, this routine 6145/// doesn't need to call UsualUnaryConversions or UsualArithmeticConversions. 6146QualType Sema::CheckIncrementDecrementOperand(Expr *Op, SourceLocation OpLoc, 6147 bool isInc, bool isPrefix) { 6148 if (Op->isTypeDependent()) 6149 return Context.DependentTy; 6150 6151 QualType ResType = Op->getType(); 6152 assert(!ResType.isNull() && "no type for increment/decrement expression"); 6153 6154 if (getLangOptions().CPlusPlus && ResType->isBooleanType()) { 6155 // Decrement of bool is not allowed. 6156 if (!isInc) { 6157 Diag(OpLoc, diag::err_decrement_bool) << Op->getSourceRange(); 6158 return QualType(); 6159 } 6160 // Increment of bool sets it to true, but is deprecated. 6161 Diag(OpLoc, diag::warn_increment_bool) << Op->getSourceRange(); 6162 } else if (ResType->isRealType()) { 6163 // OK! 6164 } else if (ResType->isAnyPointerType()) { 6165 QualType PointeeTy = ResType->getPointeeType(); 6166 6167 // C99 6.5.2.4p2, 6.5.6p2 6168 if (PointeeTy->isVoidType()) { 6169 if (getLangOptions().CPlusPlus) { 6170 Diag(OpLoc, diag::err_typecheck_pointer_arith_void_type) 6171 << Op->getSourceRange(); 6172 return QualType(); 6173 } 6174 6175 // Pointer to void is a GNU extension in C. 6176 Diag(OpLoc, diag::ext_gnu_void_ptr) << Op->getSourceRange(); 6177 } else if (PointeeTy->isFunctionType()) { 6178 if (getLangOptions().CPlusPlus) { 6179 Diag(OpLoc, diag::err_typecheck_pointer_arith_function_type) 6180 << Op->getType() << Op->getSourceRange(); 6181 return QualType(); 6182 } 6183 6184 Diag(OpLoc, diag::ext_gnu_ptr_func_arith) 6185 << ResType << Op->getSourceRange(); 6186 } else if (RequireCompleteType(OpLoc, PointeeTy, 6187 PDiag(diag::err_typecheck_arithmetic_incomplete_type) 6188 << Op->getSourceRange() 6189 << ResType)) 6190 return QualType(); 6191 // Diagnose bad cases where we step over interface counts. 6192 else if (PointeeTy->isObjCObjectType() && LangOpts.ObjCNonFragileABI) { 6193 Diag(OpLoc, diag::err_arithmetic_nonfragile_interface) 6194 << PointeeTy << Op->getSourceRange(); 6195 return QualType(); 6196 } 6197 } else if (ResType->isAnyComplexType()) { 6198 // C99 does not support ++/-- on complex types, we allow as an extension. 6199 Diag(OpLoc, diag::ext_integer_increment_complex) 6200 << ResType << Op->getSourceRange(); 6201 } else { 6202 Diag(OpLoc, diag::err_typecheck_illegal_increment_decrement) 6203 << ResType << int(isInc) << Op->getSourceRange(); 6204 return QualType(); 6205 } 6206 // At this point, we know we have a real, complex or pointer type. 6207 // Now make sure the operand is a modifiable lvalue. 6208 if (CheckForModifiableLvalue(Op, OpLoc, *this)) 6209 return QualType(); 6210 // In C++, a prefix increment is the same type as the operand. Otherwise 6211 // (in C or with postfix), the increment is the unqualified type of the 6212 // operand. 6213 return isPrefix && getLangOptions().CPlusPlus 6214 ? ResType : ResType.getUnqualifiedType(); 6215} 6216 6217void Sema::ConvertPropertyAssignment(Expr *LHS, Expr *&RHS, QualType& LHSTy) { 6218 bool copyInit = false; 6219 if (const ObjCImplicitSetterGetterRefExpr *OISGE = 6220 dyn_cast<ObjCImplicitSetterGetterRefExpr>(LHS)) { 6221 // If using property-dot syntax notation for assignment, and there is a 6222 // setter, RHS expression is being passed to the setter argument. So, 6223 // type conversion (and comparison) is RHS to setter's argument type. 6224 if (const ObjCMethodDecl *SetterMD = OISGE->getSetterMethod()) { 6225 ObjCMethodDecl::param_iterator P = SetterMD->param_begin(); 6226 LHSTy = (*P)->getType(); 6227 } 6228 copyInit = (getLangOptions().CPlusPlus && LHSTy->isRecordType()); 6229 } 6230 else 6231 copyInit = (getLangOptions().CPlusPlus && isa<ObjCPropertyRefExpr>(LHS) && 6232 LHSTy->isRecordType()); 6233 if (copyInit) { 6234 InitializedEntity Entity = 6235 InitializedEntity::InitializeParameter(LHSTy); 6236 Expr *Arg = RHS; 6237 ExprResult ArgE = PerformCopyInitialization(Entity, SourceLocation(), 6238 Owned(Arg)); 6239 if (!ArgE.isInvalid()) 6240 RHS = ArgE.takeAs<Expr>(); 6241 } 6242} 6243 6244 6245/// getPrimaryDecl - Helper function for CheckAddressOfOperand(). 6246/// This routine allows us to typecheck complex/recursive expressions 6247/// where the declaration is needed for type checking. We only need to 6248/// handle cases when the expression references a function designator 6249/// or is an lvalue. Here are some examples: 6250/// - &(x) => x 6251/// - &*****f => f for f a function designator. 6252/// - &s.xx => s 6253/// - &s.zz[1].yy -> s, if zz is an array 6254/// - *(x + 1) -> x, if x is an array 6255/// - &"123"[2] -> 0 6256/// - & __real__ x -> x 6257static NamedDecl *getPrimaryDecl(Expr *E) { 6258 switch (E->getStmtClass()) { 6259 case Stmt::DeclRefExprClass: 6260 return cast<DeclRefExpr>(E)->getDecl(); 6261 case Stmt::MemberExprClass: 6262 // If this is an arrow operator, the address is an offset from 6263 // the base's value, so the object the base refers to is 6264 // irrelevant. 6265 if (cast<MemberExpr>(E)->isArrow()) 6266 return 0; 6267 // Otherwise, the expression refers to a part of the base 6268 return getPrimaryDecl(cast<MemberExpr>(E)->getBase()); 6269 case Stmt::ArraySubscriptExprClass: { 6270 // FIXME: This code shouldn't be necessary! We should catch the implicit 6271 // promotion of register arrays earlier. 6272 Expr* Base = cast<ArraySubscriptExpr>(E)->getBase(); 6273 if (ImplicitCastExpr* ICE = dyn_cast<ImplicitCastExpr>(Base)) { 6274 if (ICE->getSubExpr()->getType()->isArrayType()) 6275 return getPrimaryDecl(ICE->getSubExpr()); 6276 } 6277 return 0; 6278 } 6279 case Stmt::UnaryOperatorClass: { 6280 UnaryOperator *UO = cast<UnaryOperator>(E); 6281 6282 switch(UO->getOpcode()) { 6283 case UO_Real: 6284 case UO_Imag: 6285 case UO_Extension: 6286 return getPrimaryDecl(UO->getSubExpr()); 6287 default: 6288 return 0; 6289 } 6290 } 6291 case Stmt::ParenExprClass: 6292 return getPrimaryDecl(cast<ParenExpr>(E)->getSubExpr()); 6293 case Stmt::ImplicitCastExprClass: 6294 // If the result of an implicit cast is an l-value, we care about 6295 // the sub-expression; otherwise, the result here doesn't matter. 6296 return getPrimaryDecl(cast<ImplicitCastExpr>(E)->getSubExpr()); 6297 default: 6298 return 0; 6299 } 6300} 6301 6302/// CheckAddressOfOperand - The operand of & must be either a function 6303/// designator or an lvalue designating an object. If it is an lvalue, the 6304/// object cannot be declared with storage class register or be a bit field. 6305/// Note: The usual conversions are *not* applied to the operand of the & 6306/// operator (C99 6.3.2.1p[2-4]), and its result is never an lvalue. 6307/// In C++, the operand might be an overloaded function name, in which case 6308/// we allow the '&' but retain the overloaded-function type. 6309QualType Sema::CheckAddressOfOperand(Expr *OrigOp, SourceLocation OpLoc) { 6310 if (OrigOp->isTypeDependent()) 6311 return Context.DependentTy; 6312 if (OrigOp->getType() == Context.OverloadTy) 6313 return Context.OverloadTy; 6314 6315 // Make sure to ignore parentheses in subsequent checks 6316 Expr *op = OrigOp->IgnoreParens(); 6317 6318 if (getLangOptions().C99) { 6319 // Implement C99-only parts of addressof rules. 6320 if (UnaryOperator* uOp = dyn_cast<UnaryOperator>(op)) { 6321 if (uOp->getOpcode() == UO_Deref) 6322 // Per C99 6.5.3.2, the address of a deref always returns a valid result 6323 // (assuming the deref expression is valid). 6324 return uOp->getSubExpr()->getType(); 6325 } 6326 // Technically, there should be a check for array subscript 6327 // expressions here, but the result of one is always an lvalue anyway. 6328 } 6329 NamedDecl *dcl = getPrimaryDecl(op); 6330 Expr::isLvalueResult lval = op->isLvalue(Context); 6331 6332 if (lval == Expr::LV_ClassTemporary) { 6333 Diag(OpLoc, isSFINAEContext()? diag::err_typecheck_addrof_class_temporary 6334 : diag::ext_typecheck_addrof_class_temporary) 6335 << op->getType() << op->getSourceRange(); 6336 if (isSFINAEContext()) 6337 return QualType(); 6338 } else if (isa<ObjCSelectorExpr>(op)) { 6339 return Context.getPointerType(op->getType()); 6340 } else if (lval == Expr::LV_MemberFunction) { 6341 // If it's an instance method, make a member pointer. 6342 // The expression must have exactly the form &A::foo. 6343 6344 // If the underlying expression isn't a decl ref, give up. 6345 if (!isa<DeclRefExpr>(op)) { 6346 Diag(OpLoc, diag::err_invalid_form_pointer_member_function) 6347 << OrigOp->getSourceRange(); 6348 return QualType(); 6349 } 6350 DeclRefExpr *DRE = cast<DeclRefExpr>(op); 6351 CXXMethodDecl *MD = cast<CXXMethodDecl>(DRE->getDecl()); 6352 6353 // The id-expression was parenthesized. 6354 if (OrigOp != DRE) { 6355 Diag(OpLoc, diag::err_parens_pointer_member_function) 6356 << OrigOp->getSourceRange(); 6357 6358 // The method was named without a qualifier. 6359 } else if (!DRE->getQualifier()) { 6360 Diag(OpLoc, diag::err_unqualified_pointer_member_function) 6361 << op->getSourceRange(); 6362 } 6363 6364 return Context.getMemberPointerType(op->getType(), 6365 Context.getTypeDeclType(MD->getParent()).getTypePtr()); 6366 } else if (lval != Expr::LV_Valid && lval != Expr::LV_IncompleteVoidType) { 6367 // C99 6.5.3.2p1 6368 // The operand must be either an l-value or a function designator 6369 if (!op->getType()->isFunctionType()) { 6370 // FIXME: emit more specific diag... 6371 Diag(OpLoc, diag::err_typecheck_invalid_lvalue_addrof) 6372 << op->getSourceRange(); 6373 return QualType(); 6374 } 6375 } else if (op->getBitField()) { // C99 6.5.3.2p1 6376 // The operand cannot be a bit-field 6377 Diag(OpLoc, diag::err_typecheck_address_of) 6378 << "bit-field" << op->getSourceRange(); 6379 return QualType(); 6380 } else if (op->refersToVectorElement()) { 6381 // The operand cannot be an element of a vector 6382 Diag(OpLoc, diag::err_typecheck_address_of) 6383 << "vector element" << op->getSourceRange(); 6384 return QualType(); 6385 } else if (isa<ObjCPropertyRefExpr>(op)) { 6386 // cannot take address of a property expression. 6387 Diag(OpLoc, diag::err_typecheck_address_of) 6388 << "property expression" << op->getSourceRange(); 6389 return QualType(); 6390 } else if (ConditionalOperator *CO = dyn_cast<ConditionalOperator>(op)) { 6391 // FIXME: Can LHS ever be null here? 6392 if (!CheckAddressOfOperand(CO->getTrueExpr(), OpLoc).isNull()) 6393 return CheckAddressOfOperand(CO->getFalseExpr(), OpLoc); 6394 } else if (dcl) { // C99 6.5.3.2p1 6395 // We have an lvalue with a decl. Make sure the decl is not declared 6396 // with the register storage-class specifier. 6397 if (const VarDecl *vd = dyn_cast<VarDecl>(dcl)) { 6398 // in C++ it is not error to take address of a register 6399 // variable (c++03 7.1.1P3) 6400 if (vd->getStorageClass() == SC_Register && 6401 !getLangOptions().CPlusPlus) { 6402 Diag(OpLoc, diag::err_typecheck_address_of) 6403 << "register variable" << op->getSourceRange(); 6404 return QualType(); 6405 } 6406 } else if (isa<FunctionTemplateDecl>(dcl)) { 6407 return Context.OverloadTy; 6408 } else if (FieldDecl *FD = dyn_cast<FieldDecl>(dcl)) { 6409 // Okay: we can take the address of a field. 6410 // Could be a pointer to member, though, if there is an explicit 6411 // scope qualifier for the class. 6412 if (isa<DeclRefExpr>(op) && cast<DeclRefExpr>(op)->getQualifier()) { 6413 DeclContext *Ctx = dcl->getDeclContext(); 6414 if (Ctx && Ctx->isRecord()) { 6415 if (FD->getType()->isReferenceType()) { 6416 Diag(OpLoc, 6417 diag::err_cannot_form_pointer_to_member_of_reference_type) 6418 << FD->getDeclName() << FD->getType(); 6419 return QualType(); 6420 } 6421 6422 return Context.getMemberPointerType(op->getType(), 6423 Context.getTypeDeclType(cast<RecordDecl>(Ctx)).getTypePtr()); 6424 } 6425 } 6426 } else if (!isa<FunctionDecl>(dcl)) 6427 assert(0 && "Unknown/unexpected decl type"); 6428 } 6429 6430 if (lval == Expr::LV_IncompleteVoidType) { 6431 // Taking the address of a void variable is technically illegal, but we 6432 // allow it in cases which are otherwise valid. 6433 // Example: "extern void x; void* y = &x;". 6434 Diag(OpLoc, diag::ext_typecheck_addrof_void) << op->getSourceRange(); 6435 } 6436 6437 // If the operand has type "type", the result has type "pointer to type". 6438 if (op->getType()->isObjCObjectType()) 6439 return Context.getObjCObjectPointerType(op->getType()); 6440 return Context.getPointerType(op->getType()); 6441} 6442 6443/// CheckIndirectionOperand - Type check unary indirection (prefix '*'). 6444QualType Sema::CheckIndirectionOperand(Expr *Op, SourceLocation OpLoc) { 6445 if (Op->isTypeDependent()) 6446 return Context.DependentTy; 6447 6448 UsualUnaryConversions(Op); 6449 QualType OpTy = Op->getType(); 6450 QualType Result; 6451 6452 // Note that per both C89 and C99, indirection is always legal, even if OpTy 6453 // is an incomplete type or void. It would be possible to warn about 6454 // dereferencing a void pointer, but it's completely well-defined, and such a 6455 // warning is unlikely to catch any mistakes. 6456 if (const PointerType *PT = OpTy->getAs<PointerType>()) 6457 Result = PT->getPointeeType(); 6458 else if (const ObjCObjectPointerType *OPT = 6459 OpTy->getAs<ObjCObjectPointerType>()) 6460 Result = OPT->getPointeeType(); 6461 6462 if (Result.isNull()) { 6463 Diag(OpLoc, diag::err_typecheck_indirection_requires_pointer) 6464 << OpTy << Op->getSourceRange(); 6465 return QualType(); 6466 } 6467 6468 return Result; 6469} 6470 6471static inline BinaryOperatorKind ConvertTokenKindToBinaryOpcode( 6472 tok::TokenKind Kind) { 6473 BinaryOperatorKind Opc; 6474 switch (Kind) { 6475 default: assert(0 && "Unknown binop!"); 6476 case tok::periodstar: Opc = BO_PtrMemD; break; 6477 case tok::arrowstar: Opc = BO_PtrMemI; break; 6478 case tok::star: Opc = BO_Mul; break; 6479 case tok::slash: Opc = BO_Div; break; 6480 case tok::percent: Opc = BO_Rem; break; 6481 case tok::plus: Opc = BO_Add; break; 6482 case tok::minus: Opc = BO_Sub; break; 6483 case tok::lessless: Opc = BO_Shl; break; 6484 case tok::greatergreater: Opc = BO_Shr; break; 6485 case tok::lessequal: Opc = BO_LE; break; 6486 case tok::less: Opc = BO_LT; break; 6487 case tok::greaterequal: Opc = BO_GE; break; 6488 case tok::greater: Opc = BO_GT; break; 6489 case tok::exclaimequal: Opc = BO_NE; break; 6490 case tok::equalequal: Opc = BO_EQ; break; 6491 case tok::amp: Opc = BO_And; break; 6492 case tok::caret: Opc = BO_Xor; break; 6493 case tok::pipe: Opc = BO_Or; break; 6494 case tok::ampamp: Opc = BO_LAnd; break; 6495 case tok::pipepipe: Opc = BO_LOr; break; 6496 case tok::equal: Opc = BO_Assign; break; 6497 case tok::starequal: Opc = BO_MulAssign; break; 6498 case tok::slashequal: Opc = BO_DivAssign; break; 6499 case tok::percentequal: Opc = BO_RemAssign; break; 6500 case tok::plusequal: Opc = BO_AddAssign; break; 6501 case tok::minusequal: Opc = BO_SubAssign; break; 6502 case tok::lesslessequal: Opc = BO_ShlAssign; break; 6503 case tok::greatergreaterequal: Opc = BO_ShrAssign; break; 6504 case tok::ampequal: Opc = BO_AndAssign; break; 6505 case tok::caretequal: Opc = BO_XorAssign; break; 6506 case tok::pipeequal: Opc = BO_OrAssign; break; 6507 case tok::comma: Opc = BO_Comma; break; 6508 } 6509 return Opc; 6510} 6511 6512static inline UnaryOperatorKind ConvertTokenKindToUnaryOpcode( 6513 tok::TokenKind Kind) { 6514 UnaryOperatorKind Opc; 6515 switch (Kind) { 6516 default: assert(0 && "Unknown unary op!"); 6517 case tok::plusplus: Opc = UO_PreInc; break; 6518 case tok::minusminus: Opc = UO_PreDec; break; 6519 case tok::amp: Opc = UO_AddrOf; break; 6520 case tok::star: Opc = UO_Deref; break; 6521 case tok::plus: Opc = UO_Plus; break; 6522 case tok::minus: Opc = UO_Minus; break; 6523 case tok::tilde: Opc = UO_Not; break; 6524 case tok::exclaim: Opc = UO_LNot; break; 6525 case tok::kw___real: Opc = UO_Real; break; 6526 case tok::kw___imag: Opc = UO_Imag; break; 6527 case tok::kw___extension__: Opc = UO_Extension; break; 6528 } 6529 return Opc; 6530} 6531 6532/// CreateBuiltinBinOp - Creates a new built-in binary operation with 6533/// operator @p Opc at location @c TokLoc. This routine only supports 6534/// built-in operations; ActOnBinOp handles overloaded operators. 6535ExprResult Sema::CreateBuiltinBinOp(SourceLocation OpLoc, 6536 unsigned Op, 6537 Expr *lhs, Expr *rhs) { 6538 QualType ResultTy; // Result type of the binary operator. 6539 BinaryOperatorKind Opc = (BinaryOperatorKind) Op; 6540 // The following two variables are used for compound assignment operators 6541 QualType CompLHSTy; // Type of LHS after promotions for computation 6542 QualType CompResultTy; // Type of computation result 6543 6544 switch (Opc) { 6545 case BO_Assign: 6546 ResultTy = CheckAssignmentOperands(lhs, rhs, OpLoc, QualType()); 6547 break; 6548 case BO_PtrMemD: 6549 case BO_PtrMemI: 6550 ResultTy = CheckPointerToMemberOperands(lhs, rhs, OpLoc, 6551 Opc == BO_PtrMemI); 6552 break; 6553 case BO_Mul: 6554 case BO_Div: 6555 ResultTy = CheckMultiplyDivideOperands(lhs, rhs, OpLoc, false, 6556 Opc == BO_Div); 6557 break; 6558 case BO_Rem: 6559 ResultTy = CheckRemainderOperands(lhs, rhs, OpLoc); 6560 break; 6561 case BO_Add: 6562 ResultTy = CheckAdditionOperands(lhs, rhs, OpLoc); 6563 break; 6564 case BO_Sub: 6565 ResultTy = CheckSubtractionOperands(lhs, rhs, OpLoc); 6566 break; 6567 case BO_Shl: 6568 case BO_Shr: 6569 ResultTy = CheckShiftOperands(lhs, rhs, OpLoc); 6570 break; 6571 case BO_LE: 6572 case BO_LT: 6573 case BO_GE: 6574 case BO_GT: 6575 ResultTy = CheckCompareOperands(lhs, rhs, OpLoc, Opc, true); 6576 break; 6577 case BO_EQ: 6578 case BO_NE: 6579 ResultTy = CheckCompareOperands(lhs, rhs, OpLoc, Opc, false); 6580 break; 6581 case BO_And: 6582 case BO_Xor: 6583 case BO_Or: 6584 ResultTy = CheckBitwiseOperands(lhs, rhs, OpLoc); 6585 break; 6586 case BO_LAnd: 6587 case BO_LOr: 6588 ResultTy = CheckLogicalOperands(lhs, rhs, OpLoc, Opc); 6589 break; 6590 case BO_MulAssign: 6591 case BO_DivAssign: 6592 CompResultTy = CheckMultiplyDivideOperands(lhs, rhs, OpLoc, true, 6593 Opc == BO_DivAssign); 6594 CompLHSTy = CompResultTy; 6595 if (!CompResultTy.isNull()) 6596 ResultTy = CheckAssignmentOperands(lhs, rhs, OpLoc, CompResultTy); 6597 break; 6598 case BO_RemAssign: 6599 CompResultTy = CheckRemainderOperands(lhs, rhs, OpLoc, true); 6600 CompLHSTy = CompResultTy; 6601 if (!CompResultTy.isNull()) 6602 ResultTy = CheckAssignmentOperands(lhs, rhs, OpLoc, CompResultTy); 6603 break; 6604 case BO_AddAssign: 6605 CompResultTy = CheckAdditionOperands(lhs, rhs, OpLoc, &CompLHSTy); 6606 if (!CompResultTy.isNull()) 6607 ResultTy = CheckAssignmentOperands(lhs, rhs, OpLoc, CompResultTy); 6608 break; 6609 case BO_SubAssign: 6610 CompResultTy = CheckSubtractionOperands(lhs, rhs, OpLoc, &CompLHSTy); 6611 if (!CompResultTy.isNull()) 6612 ResultTy = CheckAssignmentOperands(lhs, rhs, OpLoc, CompResultTy); 6613 break; 6614 case BO_ShlAssign: 6615 case BO_ShrAssign: 6616 CompResultTy = CheckShiftOperands(lhs, rhs, OpLoc, true); 6617 CompLHSTy = CompResultTy; 6618 if (!CompResultTy.isNull()) 6619 ResultTy = CheckAssignmentOperands(lhs, rhs, OpLoc, CompResultTy); 6620 break; 6621 case BO_AndAssign: 6622 case BO_XorAssign: 6623 case BO_OrAssign: 6624 CompResultTy = CheckBitwiseOperands(lhs, rhs, OpLoc, true); 6625 CompLHSTy = CompResultTy; 6626 if (!CompResultTy.isNull()) 6627 ResultTy = CheckAssignmentOperands(lhs, rhs, OpLoc, CompResultTy); 6628 break; 6629 case BO_Comma: 6630 ResultTy = CheckCommaOperands(lhs, rhs, OpLoc); 6631 break; 6632 } 6633 if (ResultTy.isNull()) 6634 return ExprError(); 6635 if (ResultTy->isObjCObjectType() && LangOpts.ObjCNonFragileABI) { 6636 if (Opc >= BO_Assign && Opc <= BO_OrAssign) 6637 Diag(OpLoc, diag::err_assignment_requires_nonfragile_object) 6638 << ResultTy; 6639 } 6640 if (CompResultTy.isNull()) 6641 return Owned(new (Context) BinaryOperator(lhs, rhs, Opc, ResultTy, OpLoc)); 6642 else 6643 return Owned(new (Context) CompoundAssignOperator(lhs, rhs, Opc, ResultTy, 6644 CompLHSTy, CompResultTy, 6645 OpLoc)); 6646} 6647 6648/// SuggestParentheses - Emit a diagnostic together with a fixit hint that wraps 6649/// ParenRange in parentheses. 6650static void SuggestParentheses(Sema &Self, SourceLocation Loc, 6651 const PartialDiagnostic &PD, 6652 const PartialDiagnostic &FirstNote, 6653 SourceRange FirstParenRange, 6654 const PartialDiagnostic &SecondNote, 6655 SourceRange SecondParenRange) { 6656 Self.Diag(Loc, PD); 6657 6658 if (!FirstNote.getDiagID()) 6659 return; 6660 6661 SourceLocation EndLoc = Self.PP.getLocForEndOfToken(FirstParenRange.getEnd()); 6662 if (!FirstParenRange.getEnd().isFileID() || EndLoc.isInvalid()) { 6663 // We can't display the parentheses, so just return. 6664 return; 6665 } 6666 6667 Self.Diag(Loc, FirstNote) 6668 << FixItHint::CreateInsertion(FirstParenRange.getBegin(), "(") 6669 << FixItHint::CreateInsertion(EndLoc, ")"); 6670 6671 if (!SecondNote.getDiagID()) 6672 return; 6673 6674 EndLoc = Self.PP.getLocForEndOfToken(SecondParenRange.getEnd()); 6675 if (!SecondParenRange.getEnd().isFileID() || EndLoc.isInvalid()) { 6676 // We can't display the parentheses, so just dig the 6677 // warning/error and return. 6678 Self.Diag(Loc, SecondNote); 6679 return; 6680 } 6681 6682 Self.Diag(Loc, SecondNote) 6683 << FixItHint::CreateInsertion(SecondParenRange.getBegin(), "(") 6684 << FixItHint::CreateInsertion(EndLoc, ")"); 6685} 6686 6687/// DiagnoseBitwisePrecedence - Emit a warning when bitwise and comparison 6688/// operators are mixed in a way that suggests that the programmer forgot that 6689/// comparison operators have higher precedence. The most typical example of 6690/// such code is "flags & 0x0020 != 0", which is equivalent to "flags & 1". 6691static void DiagnoseBitwisePrecedence(Sema &Self, BinaryOperatorKind Opc, 6692 SourceLocation OpLoc,Expr *lhs,Expr *rhs){ 6693 typedef BinaryOperator BinOp; 6694 BinOp::Opcode lhsopc = static_cast<BinOp::Opcode>(-1), 6695 rhsopc = static_cast<BinOp::Opcode>(-1); 6696 if (BinOp *BO = dyn_cast<BinOp>(lhs)) 6697 lhsopc = BO->getOpcode(); 6698 if (BinOp *BO = dyn_cast<BinOp>(rhs)) 6699 rhsopc = BO->getOpcode(); 6700 6701 // Subs are not binary operators. 6702 if (lhsopc == -1 && rhsopc == -1) 6703 return; 6704 6705 // Bitwise operations are sometimes used as eager logical ops. 6706 // Don't diagnose this. 6707 if ((BinOp::isComparisonOp(lhsopc) || BinOp::isBitwiseOp(lhsopc)) && 6708 (BinOp::isComparisonOp(rhsopc) || BinOp::isBitwiseOp(rhsopc))) 6709 return; 6710 6711 if (BinOp::isComparisonOp(lhsopc)) 6712 SuggestParentheses(Self, OpLoc, 6713 Self.PDiag(diag::warn_precedence_bitwise_rel) 6714 << SourceRange(lhs->getLocStart(), OpLoc) 6715 << BinOp::getOpcodeStr(Opc) << BinOp::getOpcodeStr(lhsopc), 6716 Self.PDiag(diag::note_precedence_bitwise_first) 6717 << BinOp::getOpcodeStr(Opc), 6718 SourceRange(cast<BinOp>(lhs)->getRHS()->getLocStart(), rhs->getLocEnd()), 6719 Self.PDiag(diag::note_precedence_bitwise_silence) 6720 << BinOp::getOpcodeStr(lhsopc), 6721 lhs->getSourceRange()); 6722 else if (BinOp::isComparisonOp(rhsopc)) 6723 SuggestParentheses(Self, OpLoc, 6724 Self.PDiag(diag::warn_precedence_bitwise_rel) 6725 << SourceRange(OpLoc, rhs->getLocEnd()) 6726 << BinOp::getOpcodeStr(Opc) << BinOp::getOpcodeStr(rhsopc), 6727 Self.PDiag(diag::note_precedence_bitwise_first) 6728 << BinOp::getOpcodeStr(Opc), 6729 SourceRange(lhs->getLocEnd(), cast<BinOp>(rhs)->getLHS()->getLocStart()), 6730 Self.PDiag(diag::note_precedence_bitwise_silence) 6731 << BinOp::getOpcodeStr(rhsopc), 6732 rhs->getSourceRange()); 6733} 6734 6735/// DiagnoseBinOpPrecedence - Emit warnings for expressions with tricky 6736/// precedence. This currently diagnoses only "arg1 'bitwise' arg2 'eq' arg3". 6737/// But it could also warn about arg1 && arg2 || arg3, as GCC 4.3+ does. 6738static void DiagnoseBinOpPrecedence(Sema &Self, BinaryOperatorKind Opc, 6739 SourceLocation OpLoc, Expr *lhs, Expr *rhs){ 6740 if (BinaryOperator::isBitwiseOp(Opc)) 6741 DiagnoseBitwisePrecedence(Self, Opc, OpLoc, lhs, rhs); 6742} 6743 6744// Binary Operators. 'Tok' is the token for the operator. 6745ExprResult Sema::ActOnBinOp(Scope *S, SourceLocation TokLoc, 6746 tok::TokenKind Kind, 6747 Expr *lhs, Expr *rhs) { 6748 BinaryOperatorKind Opc = ConvertTokenKindToBinaryOpcode(Kind); 6749 assert((lhs != 0) && "ActOnBinOp(): missing left expression"); 6750 assert((rhs != 0) && "ActOnBinOp(): missing right expression"); 6751 6752 // Emit warnings for tricky precedence issues, e.g. "bitfield & 0x4 == 0" 6753 DiagnoseBinOpPrecedence(*this, Opc, TokLoc, lhs, rhs); 6754 6755 return BuildBinOp(S, TokLoc, Opc, lhs, rhs); 6756} 6757 6758ExprResult Sema::BuildBinOp(Scope *S, SourceLocation OpLoc, 6759 BinaryOperatorKind Opc, 6760 Expr *lhs, Expr *rhs) { 6761 if (getLangOptions().CPlusPlus && 6762 ((!isa<ObjCImplicitSetterGetterRefExpr>(lhs) && 6763 !isa<ObjCPropertyRefExpr>(lhs)) 6764 || rhs->isTypeDependent() || Opc != BO_Assign) && 6765 (lhs->getType()->isOverloadableType() || 6766 rhs->getType()->isOverloadableType())) { 6767 // Find all of the overloaded operators visible from this 6768 // point. We perform both an operator-name lookup from the local 6769 // scope and an argument-dependent lookup based on the types of 6770 // the arguments. 6771 UnresolvedSet<16> Functions; 6772 OverloadedOperatorKind OverOp = BinaryOperator::getOverloadedOperator(Opc); 6773 if (S && OverOp != OO_None) 6774 LookupOverloadedOperatorName(OverOp, S, lhs->getType(), rhs->getType(), 6775 Functions); 6776 6777 // Build the (potentially-overloaded, potentially-dependent) 6778 // binary operation. 6779 return CreateOverloadedBinOp(OpLoc, Opc, Functions, lhs, rhs); 6780 } 6781 6782 // Build a built-in binary operation. 6783 return CreateBuiltinBinOp(OpLoc, Opc, lhs, rhs); 6784} 6785 6786ExprResult Sema::CreateBuiltinUnaryOp(SourceLocation OpLoc, 6787 unsigned OpcIn, 6788 Expr *Input) { 6789 UnaryOperatorKind Opc = static_cast<UnaryOperatorKind>(OpcIn); 6790 6791 QualType resultType; 6792 switch (Opc) { 6793 case UO_PreInc: 6794 case UO_PreDec: 6795 case UO_PostInc: 6796 case UO_PostDec: 6797 resultType = CheckIncrementDecrementOperand(Input, OpLoc, 6798 Opc == UO_PreInc || 6799 Opc == UO_PostInc, 6800 Opc == UO_PreInc || 6801 Opc == UO_PreDec); 6802 break; 6803 case UO_AddrOf: 6804 resultType = CheckAddressOfOperand(Input, OpLoc); 6805 break; 6806 case UO_Deref: 6807 DefaultFunctionArrayLvalueConversion(Input); 6808 resultType = CheckIndirectionOperand(Input, OpLoc); 6809 break; 6810 case UO_Plus: 6811 case UO_Minus: 6812 UsualUnaryConversions(Input); 6813 resultType = Input->getType(); 6814 if (resultType->isDependentType()) 6815 break; 6816 if (resultType->isArithmeticType() || // C99 6.5.3.3p1 6817 resultType->isVectorType()) 6818 break; 6819 else if (getLangOptions().CPlusPlus && // C++ [expr.unary.op]p6-7 6820 resultType->isEnumeralType()) 6821 break; 6822 else if (getLangOptions().CPlusPlus && // C++ [expr.unary.op]p6 6823 Opc == UO_Plus && 6824 resultType->isPointerType()) 6825 break; 6826 6827 return ExprError(Diag(OpLoc, diag::err_typecheck_unary_expr) 6828 << resultType << Input->getSourceRange()); 6829 case UO_Not: // bitwise complement 6830 UsualUnaryConversions(Input); 6831 resultType = Input->getType(); 6832 if (resultType->isDependentType()) 6833 break; 6834 // C99 6.5.3.3p1. We allow complex int and float as a GCC extension. 6835 if (resultType->isComplexType() || resultType->isComplexIntegerType()) 6836 // C99 does not support '~' for complex conjugation. 6837 Diag(OpLoc, diag::ext_integer_complement_complex) 6838 << resultType << Input->getSourceRange(); 6839 else if (!resultType->hasIntegerRepresentation()) 6840 return ExprError(Diag(OpLoc, diag::err_typecheck_unary_expr) 6841 << resultType << Input->getSourceRange()); 6842 break; 6843 case UO_LNot: // logical negation 6844 // Unlike +/-/~, integer promotions aren't done here (C99 6.5.3.3p5). 6845 DefaultFunctionArrayLvalueConversion(Input); 6846 resultType = Input->getType(); 6847 if (resultType->isDependentType()) 6848 break; 6849 if (!resultType->isScalarType()) // C99 6.5.3.3p1 6850 return ExprError(Diag(OpLoc, diag::err_typecheck_unary_expr) 6851 << resultType << Input->getSourceRange()); 6852 6853 // Do not accept &f if f is overloaded 6854 // i.e. void f(int); void f(char); bool b = &f; 6855 if (resultType == Context.OverloadTy && 6856 PerformContextuallyConvertToBool(Input)) 6857 return ExprError(); // Diagnostic is uttered above 6858 6859 // LNot always has type int. C99 6.5.3.3p5. 6860 // In C++, it's bool. C++ 5.3.1p8 6861 resultType = getLangOptions().CPlusPlus ? Context.BoolTy : Context.IntTy; 6862 break; 6863 case UO_Real: 6864 case UO_Imag: 6865 resultType = CheckRealImagOperand(Input, OpLoc, Opc == UO_Real); 6866 break; 6867 case UO_Extension: 6868 resultType = Input->getType(); 6869 break; 6870 } 6871 if (resultType.isNull()) 6872 return ExprError(); 6873 6874 return Owned(new (Context) UnaryOperator(Input, Opc, resultType, OpLoc)); 6875} 6876 6877ExprResult Sema::BuildUnaryOp(Scope *S, SourceLocation OpLoc, 6878 UnaryOperatorKind Opc, 6879 Expr *Input) { 6880 if (getLangOptions().CPlusPlus && Input->getType()->isOverloadableType() && 6881 UnaryOperator::getOverloadedOperator(Opc) != OO_None) { 6882 // Find all of the overloaded operators visible from this 6883 // point. We perform both an operator-name lookup from the local 6884 // scope and an argument-dependent lookup based on the types of 6885 // the arguments. 6886 UnresolvedSet<16> Functions; 6887 OverloadedOperatorKind OverOp = UnaryOperator::getOverloadedOperator(Opc); 6888 if (S && OverOp != OO_None) 6889 LookupOverloadedOperatorName(OverOp, S, Input->getType(), QualType(), 6890 Functions); 6891 6892 return CreateOverloadedUnaryOp(OpLoc, Opc, Functions, Input); 6893 } 6894 6895 return CreateBuiltinUnaryOp(OpLoc, Opc, Input); 6896} 6897 6898// Unary Operators. 'Tok' is the token for the operator. 6899ExprResult Sema::ActOnUnaryOp(Scope *S, SourceLocation OpLoc, 6900 tok::TokenKind Op, Expr *Input) { 6901 return BuildUnaryOp(S, OpLoc, ConvertTokenKindToUnaryOpcode(Op), Input); 6902} 6903 6904/// ActOnAddrLabel - Parse the GNU address of label extension: "&&foo". 6905ExprResult Sema::ActOnAddrLabel(SourceLocation OpLoc, 6906 SourceLocation LabLoc, 6907 IdentifierInfo *LabelII) { 6908 // Look up the record for this label identifier. 6909 LabelStmt *&LabelDecl = getCurFunction()->LabelMap[LabelII]; 6910 6911 // If we haven't seen this label yet, create a forward reference. It 6912 // will be validated and/or cleaned up in ActOnFinishFunctionBody. 6913 if (LabelDecl == 0) 6914 LabelDecl = new (Context) LabelStmt(LabLoc, LabelII, 0); 6915 6916 LabelDecl->setUsed(); 6917 // Create the AST node. The address of a label always has type 'void*'. 6918 return Owned(new (Context) AddrLabelExpr(OpLoc, LabLoc, LabelDecl, 6919 Context.getPointerType(Context.VoidTy))); 6920} 6921 6922ExprResult 6923Sema::ActOnStmtExpr(SourceLocation LPLoc, Stmt *SubStmt, 6924 SourceLocation RPLoc) { // "({..})" 6925 assert(SubStmt && isa<CompoundStmt>(SubStmt) && "Invalid action invocation!"); 6926 CompoundStmt *Compound = cast<CompoundStmt>(SubStmt); 6927 6928 bool isFileScope 6929 = (getCurFunctionOrMethodDecl() == 0) && (getCurBlock() == 0); 6930 if (isFileScope) 6931 return ExprError(Diag(LPLoc, diag::err_stmtexpr_file_scope)); 6932 6933 // FIXME: there are a variety of strange constraints to enforce here, for 6934 // example, it is not possible to goto into a stmt expression apparently. 6935 // More semantic analysis is needed. 6936 6937 // If there are sub stmts in the compound stmt, take the type of the last one 6938 // as the type of the stmtexpr. 6939 QualType Ty = Context.VoidTy; 6940 6941 if (!Compound->body_empty()) { 6942 Stmt *LastStmt = Compound->body_back(); 6943 // If LastStmt is a label, skip down through into the body. 6944 while (LabelStmt *Label = dyn_cast<LabelStmt>(LastStmt)) 6945 LastStmt = Label->getSubStmt(); 6946 6947 if (Expr *LastExpr = dyn_cast<Expr>(LastStmt)) 6948 Ty = LastExpr->getType(); 6949 } 6950 6951 // FIXME: Check that expression type is complete/non-abstract; statement 6952 // expressions are not lvalues. 6953 6954 return Owned(new (Context) StmtExpr(Compound, Ty, LPLoc, RPLoc)); 6955} 6956 6957ExprResult Sema::BuildBuiltinOffsetOf(SourceLocation BuiltinLoc, 6958 TypeSourceInfo *TInfo, 6959 OffsetOfComponent *CompPtr, 6960 unsigned NumComponents, 6961 SourceLocation RParenLoc) { 6962 QualType ArgTy = TInfo->getType(); 6963 bool Dependent = ArgTy->isDependentType(); 6964 SourceRange TypeRange = TInfo->getTypeLoc().getLocalSourceRange(); 6965 6966 // We must have at least one component that refers to the type, and the first 6967 // one is known to be a field designator. Verify that the ArgTy represents 6968 // a struct/union/class. 6969 if (!Dependent && !ArgTy->isRecordType()) 6970 return ExprError(Diag(BuiltinLoc, diag::err_offsetof_record_type) 6971 << ArgTy << TypeRange); 6972 6973 // Type must be complete per C99 7.17p3 because a declaring a variable 6974 // with an incomplete type would be ill-formed. 6975 if (!Dependent 6976 && RequireCompleteType(BuiltinLoc, ArgTy, 6977 PDiag(diag::err_offsetof_incomplete_type) 6978 << TypeRange)) 6979 return ExprError(); 6980 6981 // offsetof with non-identifier designators (e.g. "offsetof(x, a.b[c])") are a 6982 // GCC extension, diagnose them. 6983 // FIXME: This diagnostic isn't actually visible because the location is in 6984 // a system header! 6985 if (NumComponents != 1) 6986 Diag(BuiltinLoc, diag::ext_offsetof_extended_field_designator) 6987 << SourceRange(CompPtr[1].LocStart, CompPtr[NumComponents-1].LocEnd); 6988 6989 bool DidWarnAboutNonPOD = false; 6990 QualType CurrentType = ArgTy; 6991 typedef OffsetOfExpr::OffsetOfNode OffsetOfNode; 6992 llvm::SmallVector<OffsetOfNode, 4> Comps; 6993 llvm::SmallVector<Expr*, 4> Exprs; 6994 for (unsigned i = 0; i != NumComponents; ++i) { 6995 const OffsetOfComponent &OC = CompPtr[i]; 6996 if (OC.isBrackets) { 6997 // Offset of an array sub-field. TODO: Should we allow vector elements? 6998 if (!CurrentType->isDependentType()) { 6999 const ArrayType *AT = Context.getAsArrayType(CurrentType); 7000 if(!AT) 7001 return ExprError(Diag(OC.LocEnd, diag::err_offsetof_array_type) 7002 << CurrentType); 7003 CurrentType = AT->getElementType(); 7004 } else 7005 CurrentType = Context.DependentTy; 7006 7007 // The expression must be an integral expression. 7008 // FIXME: An integral constant expression? 7009 Expr *Idx = static_cast<Expr*>(OC.U.E); 7010 if (!Idx->isTypeDependent() && !Idx->isValueDependent() && 7011 !Idx->getType()->isIntegerType()) 7012 return ExprError(Diag(Idx->getLocStart(), 7013 diag::err_typecheck_subscript_not_integer) 7014 << Idx->getSourceRange()); 7015 7016 // Record this array index. 7017 Comps.push_back(OffsetOfNode(OC.LocStart, Exprs.size(), OC.LocEnd)); 7018 Exprs.push_back(Idx); 7019 continue; 7020 } 7021 7022 // Offset of a field. 7023 if (CurrentType->isDependentType()) { 7024 // We have the offset of a field, but we can't look into the dependent 7025 // type. Just record the identifier of the field. 7026 Comps.push_back(OffsetOfNode(OC.LocStart, OC.U.IdentInfo, OC.LocEnd)); 7027 CurrentType = Context.DependentTy; 7028 continue; 7029 } 7030 7031 // We need to have a complete type to look into. 7032 if (RequireCompleteType(OC.LocStart, CurrentType, 7033 diag::err_offsetof_incomplete_type)) 7034 return ExprError(); 7035 7036 // Look for the designated field. 7037 const RecordType *RC = CurrentType->getAs<RecordType>(); 7038 if (!RC) 7039 return ExprError(Diag(OC.LocEnd, diag::err_offsetof_record_type) 7040 << CurrentType); 7041 RecordDecl *RD = RC->getDecl(); 7042 7043 // C++ [lib.support.types]p5: 7044 // The macro offsetof accepts a restricted set of type arguments in this 7045 // International Standard. type shall be a POD structure or a POD union 7046 // (clause 9). 7047 if (CXXRecordDecl *CRD = dyn_cast<CXXRecordDecl>(RD)) { 7048 if (!CRD->isPOD() && !DidWarnAboutNonPOD && 7049 DiagRuntimeBehavior(BuiltinLoc, 7050 PDiag(diag::warn_offsetof_non_pod_type) 7051 << SourceRange(CompPtr[0].LocStart, OC.LocEnd) 7052 << CurrentType)) 7053 DidWarnAboutNonPOD = true; 7054 } 7055 7056 // Look for the field. 7057 LookupResult R(*this, OC.U.IdentInfo, OC.LocStart, LookupMemberName); 7058 LookupQualifiedName(R, RD); 7059 FieldDecl *MemberDecl = R.getAsSingle<FieldDecl>(); 7060 if (!MemberDecl) 7061 return ExprError(Diag(BuiltinLoc, diag::err_no_member) 7062 << OC.U.IdentInfo << RD << SourceRange(OC.LocStart, 7063 OC.LocEnd)); 7064 7065 // C99 7.17p3: 7066 // (If the specified member is a bit-field, the behavior is undefined.) 7067 // 7068 // We diagnose this as an error. 7069 if (MemberDecl->getBitWidth()) { 7070 Diag(OC.LocEnd, diag::err_offsetof_bitfield) 7071 << MemberDecl->getDeclName() 7072 << SourceRange(BuiltinLoc, RParenLoc); 7073 Diag(MemberDecl->getLocation(), diag::note_bitfield_decl); 7074 return ExprError(); 7075 } 7076 7077 RecordDecl *Parent = MemberDecl->getParent(); 7078 bool AnonStructUnion = Parent->isAnonymousStructOrUnion(); 7079 if (AnonStructUnion) { 7080 do { 7081 Parent = cast<RecordDecl>(Parent->getParent()); 7082 } while (Parent->isAnonymousStructOrUnion()); 7083 } 7084 7085 // If the member was found in a base class, introduce OffsetOfNodes for 7086 // the base class indirections. 7087 CXXBasePaths Paths(/*FindAmbiguities=*/true, /*RecordPaths=*/true, 7088 /*DetectVirtual=*/false); 7089 if (IsDerivedFrom(CurrentType, Context.getTypeDeclType(Parent), Paths)) { 7090 CXXBasePath &Path = Paths.front(); 7091 for (CXXBasePath::iterator B = Path.begin(), BEnd = Path.end(); 7092 B != BEnd; ++B) 7093 Comps.push_back(OffsetOfNode(B->Base)); 7094 } 7095 7096 if (AnonStructUnion) { 7097 llvm::SmallVector<FieldDecl*, 4> Path; 7098 BuildAnonymousStructUnionMemberPath(MemberDecl, Path); 7099 unsigned n = Path.size(); 7100 for (int j = n - 1; j > -1; --j) 7101 Comps.push_back(OffsetOfNode(OC.LocStart, Path[j], OC.LocEnd)); 7102 } else { 7103 Comps.push_back(OffsetOfNode(OC.LocStart, MemberDecl, OC.LocEnd)); 7104 } 7105 CurrentType = MemberDecl->getType().getNonReferenceType(); 7106 } 7107 7108 return Owned(OffsetOfExpr::Create(Context, Context.getSizeType(), BuiltinLoc, 7109 TInfo, Comps.data(), Comps.size(), 7110 Exprs.data(), Exprs.size(), RParenLoc)); 7111} 7112 7113ExprResult Sema::ActOnBuiltinOffsetOf(Scope *S, 7114 SourceLocation BuiltinLoc, 7115 SourceLocation TypeLoc, 7116 ParsedType argty, 7117 OffsetOfComponent *CompPtr, 7118 unsigned NumComponents, 7119 SourceLocation RPLoc) { 7120 7121 TypeSourceInfo *ArgTInfo; 7122 QualType ArgTy = GetTypeFromParser(argty, &ArgTInfo); 7123 if (ArgTy.isNull()) 7124 return ExprError(); 7125 7126 if (!ArgTInfo) 7127 ArgTInfo = Context.getTrivialTypeSourceInfo(ArgTy, TypeLoc); 7128 7129 return BuildBuiltinOffsetOf(BuiltinLoc, ArgTInfo, CompPtr, NumComponents, 7130 RPLoc); 7131} 7132 7133 7134ExprResult Sema::ActOnTypesCompatibleExpr(SourceLocation BuiltinLoc, 7135 ParsedType arg1,ParsedType arg2, 7136 SourceLocation RPLoc) { 7137 TypeSourceInfo *argTInfo1; 7138 QualType argT1 = GetTypeFromParser(arg1, &argTInfo1); 7139 TypeSourceInfo *argTInfo2; 7140 QualType argT2 = GetTypeFromParser(arg2, &argTInfo2); 7141 7142 assert((!argT1.isNull() && !argT2.isNull()) && "Missing type argument(s)"); 7143 7144 return BuildTypesCompatibleExpr(BuiltinLoc, argTInfo1, argTInfo2, RPLoc); 7145} 7146 7147ExprResult 7148Sema::BuildTypesCompatibleExpr(SourceLocation BuiltinLoc, 7149 TypeSourceInfo *argTInfo1, 7150 TypeSourceInfo *argTInfo2, 7151 SourceLocation RPLoc) { 7152 if (getLangOptions().CPlusPlus) { 7153 Diag(BuiltinLoc, diag::err_types_compatible_p_in_cplusplus) 7154 << SourceRange(BuiltinLoc, RPLoc); 7155 return ExprError(); 7156 } 7157 7158 return Owned(new (Context) TypesCompatibleExpr(Context.IntTy, BuiltinLoc, 7159 argTInfo1, argTInfo2, RPLoc)); 7160} 7161 7162 7163ExprResult Sema::ActOnChooseExpr(SourceLocation BuiltinLoc, 7164 Expr *CondExpr, 7165 Expr *LHSExpr, Expr *RHSExpr, 7166 SourceLocation RPLoc) { 7167 assert((CondExpr && LHSExpr && RHSExpr) && "Missing type argument(s)"); 7168 7169 QualType resType; 7170 bool ValueDependent = false; 7171 if (CondExpr->isTypeDependent() || CondExpr->isValueDependent()) { 7172 resType = Context.DependentTy; 7173 ValueDependent = true; 7174 } else { 7175 // The conditional expression is required to be a constant expression. 7176 llvm::APSInt condEval(32); 7177 SourceLocation ExpLoc; 7178 if (!CondExpr->isIntegerConstantExpr(condEval, Context, &ExpLoc)) 7179 return ExprError(Diag(ExpLoc, 7180 diag::err_typecheck_choose_expr_requires_constant) 7181 << CondExpr->getSourceRange()); 7182 7183 // If the condition is > zero, then the AST type is the same as the LSHExpr. 7184 resType = condEval.getZExtValue() ? LHSExpr->getType() : RHSExpr->getType(); 7185 ValueDependent = condEval.getZExtValue() ? LHSExpr->isValueDependent() 7186 : RHSExpr->isValueDependent(); 7187 } 7188 7189 return Owned(new (Context) ChooseExpr(BuiltinLoc, CondExpr, LHSExpr, RHSExpr, 7190 resType, RPLoc, 7191 resType->isDependentType(), 7192 ValueDependent)); 7193} 7194 7195//===----------------------------------------------------------------------===// 7196// Clang Extensions. 7197//===----------------------------------------------------------------------===// 7198 7199/// ActOnBlockStart - This callback is invoked when a block literal is started. 7200void Sema::ActOnBlockStart(SourceLocation CaretLoc, Scope *BlockScope) { 7201 BlockDecl *Block = BlockDecl::Create(Context, CurContext, CaretLoc); 7202 PushBlockScope(BlockScope, Block); 7203 CurContext->addDecl(Block); 7204 if (BlockScope) 7205 PushDeclContext(BlockScope, Block); 7206 else 7207 CurContext = Block; 7208} 7209 7210void Sema::ActOnBlockArguments(Declarator &ParamInfo, Scope *CurScope) { 7211 assert(ParamInfo.getIdentifier()==0 && "block-id should have no identifier!"); 7212 BlockScopeInfo *CurBlock = getCurBlock(); 7213 7214 TypeSourceInfo *Sig = GetTypeForDeclarator(ParamInfo, CurScope); 7215 CurBlock->TheDecl->setSignatureAsWritten(Sig); 7216 QualType T = Sig->getType(); 7217 7218 bool isVariadic; 7219 QualType RetTy; 7220 if (const FunctionType *Fn = T->getAs<FunctionType>()) { 7221 CurBlock->FunctionType = T; 7222 RetTy = Fn->getResultType(); 7223 isVariadic = 7224 !isa<FunctionProtoType>(Fn) || cast<FunctionProtoType>(Fn)->isVariadic(); 7225 } else { 7226 RetTy = T; 7227 isVariadic = false; 7228 } 7229 7230 CurBlock->TheDecl->setIsVariadic(isVariadic); 7231 7232 // Don't allow returning an array by value. 7233 if (RetTy->isArrayType()) { 7234 Diag(ParamInfo.getSourceRange().getBegin(), diag::err_block_returns_array); 7235 return; 7236 } 7237 7238 // Don't allow returning a objc interface by value. 7239 if (RetTy->isObjCObjectType()) { 7240 Diag(ParamInfo.getSourceRange().getBegin(), 7241 diag::err_object_cannot_be_passed_returned_by_value) << 0 << RetTy; 7242 return; 7243 } 7244 7245 // Context.DependentTy is used as a placeholder for a missing block 7246 // return type. TODO: what should we do with declarators like: 7247 // ^ * { ... } 7248 // If the answer is "apply template argument deduction".... 7249 if (RetTy != Context.DependentTy) 7250 CurBlock->ReturnType = RetTy; 7251 7252 // Push block parameters from the declarator if we had them. 7253 llvm::SmallVector<ParmVarDecl*, 8> Params; 7254 if (isa<FunctionProtoType>(T)) { 7255 FunctionProtoTypeLoc TL = cast<FunctionProtoTypeLoc>(Sig->getTypeLoc()); 7256 for (unsigned I = 0, E = TL.getNumArgs(); I != E; ++I) { 7257 ParmVarDecl *Param = TL.getArg(I); 7258 if (Param->getIdentifier() == 0 && 7259 !Param->isImplicit() && 7260 !Param->isInvalidDecl() && 7261 !getLangOptions().CPlusPlus) 7262 Diag(Param->getLocation(), diag::err_parameter_name_omitted); 7263 Params.push_back(Param); 7264 } 7265 7266 // Fake up parameter variables if we have a typedef, like 7267 // ^ fntype { ... } 7268 } else if (const FunctionProtoType *Fn = T->getAs<FunctionProtoType>()) { 7269 for (FunctionProtoType::arg_type_iterator 7270 I = Fn->arg_type_begin(), E = Fn->arg_type_end(); I != E; ++I) { 7271 ParmVarDecl *Param = 7272 BuildParmVarDeclForTypedef(CurBlock->TheDecl, 7273 ParamInfo.getSourceRange().getBegin(), 7274 *I); 7275 Params.push_back(Param); 7276 } 7277 } 7278 7279 // Set the parameters on the block decl. 7280 if (!Params.empty()) 7281 CurBlock->TheDecl->setParams(Params.data(), Params.size()); 7282 7283 // Finally we can process decl attributes. 7284 ProcessDeclAttributes(CurScope, CurBlock->TheDecl, ParamInfo); 7285 7286 if (!isVariadic && CurBlock->TheDecl->getAttr<SentinelAttr>()) { 7287 Diag(ParamInfo.getAttributes()->getLoc(), 7288 diag::warn_attribute_sentinel_not_variadic) << 1; 7289 // FIXME: remove the attribute. 7290 } 7291 7292 // Put the parameter variables in scope. We can bail out immediately 7293 // if we don't have any. 7294 if (Params.empty()) 7295 return; 7296 7297 bool ShouldCheckShadow = 7298 Diags.getDiagnosticLevel(diag::warn_decl_shadow) != Diagnostic::Ignored; 7299 7300 for (BlockDecl::param_iterator AI = CurBlock->TheDecl->param_begin(), 7301 E = CurBlock->TheDecl->param_end(); AI != E; ++AI) { 7302 (*AI)->setOwningFunction(CurBlock->TheDecl); 7303 7304 // If this has an identifier, add it to the scope stack. 7305 if ((*AI)->getIdentifier()) { 7306 if (ShouldCheckShadow) 7307 CheckShadow(CurBlock->TheScope, *AI); 7308 7309 PushOnScopeChains(*AI, CurBlock->TheScope); 7310 } 7311 } 7312} 7313 7314/// ActOnBlockError - If there is an error parsing a block, this callback 7315/// is invoked to pop the information about the block from the action impl. 7316void Sema::ActOnBlockError(SourceLocation CaretLoc, Scope *CurScope) { 7317 // Pop off CurBlock, handle nested blocks. 7318 PopDeclContext(); 7319 PopFunctionOrBlockScope(); 7320 // FIXME: Delete the ParmVarDecl objects as well??? 7321} 7322 7323/// ActOnBlockStmtExpr - This is called when the body of a block statement 7324/// literal was successfully completed. ^(int x){...} 7325ExprResult Sema::ActOnBlockStmtExpr(SourceLocation CaretLoc, 7326 Stmt *Body, Scope *CurScope) { 7327 // If blocks are disabled, emit an error. 7328 if (!LangOpts.Blocks) 7329 Diag(CaretLoc, diag::err_blocks_disable); 7330 7331 BlockScopeInfo *BSI = cast<BlockScopeInfo>(FunctionScopes.back()); 7332 7333 PopDeclContext(); 7334 7335 QualType RetTy = Context.VoidTy; 7336 if (!BSI->ReturnType.isNull()) 7337 RetTy = BSI->ReturnType; 7338 7339 bool NoReturn = BSI->TheDecl->getAttr<NoReturnAttr>(); 7340 QualType BlockTy; 7341 7342 // If the user wrote a function type in some form, try to use that. 7343 if (!BSI->FunctionType.isNull()) { 7344 const FunctionType *FTy = BSI->FunctionType->getAs<FunctionType>(); 7345 7346 FunctionType::ExtInfo Ext = FTy->getExtInfo(); 7347 if (NoReturn && !Ext.getNoReturn()) Ext = Ext.withNoReturn(true); 7348 7349 // Turn protoless block types into nullary block types. 7350 if (isa<FunctionNoProtoType>(FTy)) { 7351 BlockTy = Context.getFunctionType(RetTy, 0, 0, false, 0, 7352 false, false, 0, 0, Ext); 7353 7354 // Otherwise, if we don't need to change anything about the function type, 7355 // preserve its sugar structure. 7356 } else if (FTy->getResultType() == RetTy && 7357 (!NoReturn || FTy->getNoReturnAttr())) { 7358 BlockTy = BSI->FunctionType; 7359 7360 // Otherwise, make the minimal modifications to the function type. 7361 } else { 7362 const FunctionProtoType *FPT = cast<FunctionProtoType>(FTy); 7363 BlockTy = Context.getFunctionType(RetTy, 7364 FPT->arg_type_begin(), 7365 FPT->getNumArgs(), 7366 FPT->isVariadic(), 7367 /*quals*/ 0, 7368 FPT->hasExceptionSpec(), 7369 FPT->hasAnyExceptionSpec(), 7370 FPT->getNumExceptions(), 7371 FPT->exception_begin(), 7372 Ext); 7373 } 7374 7375 // If we don't have a function type, just build one from nothing. 7376 } else { 7377 BlockTy = Context.getFunctionType(RetTy, 0, 0, false, 0, 7378 false, false, 0, 0, 7379 FunctionType::ExtInfo(NoReturn, 0, CC_Default)); 7380 } 7381 7382 // FIXME: Check that return/parameter types are complete/non-abstract 7383 DiagnoseUnusedParameters(BSI->TheDecl->param_begin(), 7384 BSI->TheDecl->param_end()); 7385 BlockTy = Context.getBlockPointerType(BlockTy); 7386 7387 // If needed, diagnose invalid gotos and switches in the block. 7388 if (getCurFunction()->NeedsScopeChecking() && !hasAnyErrorsInThisFunction()) 7389 DiagnoseInvalidJumps(cast<CompoundStmt>(Body)); 7390 7391 BSI->TheDecl->setBody(cast<CompoundStmt>(Body)); 7392 7393 bool Good = true; 7394 // Check goto/label use. 7395 for (llvm::DenseMap<IdentifierInfo*, LabelStmt*>::iterator 7396 I = BSI->LabelMap.begin(), E = BSI->LabelMap.end(); I != E; ++I) { 7397 LabelStmt *L = I->second; 7398 7399 // Verify that we have no forward references left. If so, there was a goto 7400 // or address of a label taken, but no definition of it. 7401 if (L->getSubStmt() != 0) { 7402 if (!L->isUsed()) 7403 Diag(L->getIdentLoc(), diag::warn_unused_label) << L->getName(); 7404 continue; 7405 } 7406 7407 // Emit error. 7408 Diag(L->getIdentLoc(), diag::err_undeclared_label_use) << L->getName(); 7409 Good = false; 7410 } 7411 if (!Good) { 7412 PopFunctionOrBlockScope(); 7413 return ExprError(); 7414 } 7415 7416 BlockExpr *Result = new (Context) BlockExpr(BSI->TheDecl, BlockTy, 7417 BSI->hasBlockDeclRefExprs); 7418 7419 // Issue any analysis-based warnings. 7420 const sema::AnalysisBasedWarnings::Policy &WP = 7421 AnalysisWarnings.getDefaultPolicy(); 7422 AnalysisWarnings.IssueWarnings(WP, Result); 7423 7424 PopFunctionOrBlockScope(); 7425 return Owned(Result); 7426} 7427 7428ExprResult Sema::ActOnVAArg(SourceLocation BuiltinLoc, 7429 Expr *expr, ParsedType type, 7430 SourceLocation RPLoc) { 7431 TypeSourceInfo *TInfo; 7432 QualType T = GetTypeFromParser(type, &TInfo); 7433 return BuildVAArgExpr(BuiltinLoc, expr, TInfo, RPLoc); 7434} 7435 7436ExprResult Sema::BuildVAArgExpr(SourceLocation BuiltinLoc, 7437 Expr *E, TypeSourceInfo *TInfo, 7438 SourceLocation RPLoc) { 7439 Expr *OrigExpr = E; 7440 7441 InitBuiltinVaListType(); 7442 7443 // Get the va_list type 7444 QualType VaListType = Context.getBuiltinVaListType(); 7445 if (VaListType->isArrayType()) { 7446 // Deal with implicit array decay; for example, on x86-64, 7447 // va_list is an array, but it's supposed to decay to 7448 // a pointer for va_arg. 7449 VaListType = Context.getArrayDecayedType(VaListType); 7450 // Make sure the input expression also decays appropriately. 7451 UsualUnaryConversions(E); 7452 } else { 7453 // Otherwise, the va_list argument must be an l-value because 7454 // it is modified by va_arg. 7455 if (!E->isTypeDependent() && 7456 CheckForModifiableLvalue(E, BuiltinLoc, *this)) 7457 return ExprError(); 7458 } 7459 7460 if (!E->isTypeDependent() && 7461 !Context.hasSameType(VaListType, E->getType())) { 7462 return ExprError(Diag(E->getLocStart(), 7463 diag::err_first_argument_to_va_arg_not_of_type_va_list) 7464 << OrigExpr->getType() << E->getSourceRange()); 7465 } 7466 7467 // FIXME: Check that type is complete/non-abstract 7468 // FIXME: Warn if a non-POD type is passed in. 7469 7470 QualType T = TInfo->getType().getNonLValueExprType(Context); 7471 return Owned(new (Context) VAArgExpr(BuiltinLoc, E, TInfo, RPLoc, T)); 7472} 7473 7474ExprResult Sema::ActOnGNUNullExpr(SourceLocation TokenLoc) { 7475 // The type of __null will be int or long, depending on the size of 7476 // pointers on the target. 7477 QualType Ty; 7478 if (Context.Target.getPointerWidth(0) == Context.Target.getIntWidth()) 7479 Ty = Context.IntTy; 7480 else 7481 Ty = Context.LongTy; 7482 7483 return Owned(new (Context) GNUNullExpr(Ty, TokenLoc)); 7484} 7485 7486static void MakeObjCStringLiteralFixItHint(Sema& SemaRef, QualType DstType, 7487 Expr *SrcExpr, FixItHint &Hint) { 7488 if (!SemaRef.getLangOptions().ObjC1) 7489 return; 7490 7491 const ObjCObjectPointerType *PT = DstType->getAs<ObjCObjectPointerType>(); 7492 if (!PT) 7493 return; 7494 7495 // Check if the destination is of type 'id'. 7496 if (!PT->isObjCIdType()) { 7497 // Check if the destination is the 'NSString' interface. 7498 const ObjCInterfaceDecl *ID = PT->getInterfaceDecl(); 7499 if (!ID || !ID->getIdentifier()->isStr("NSString")) 7500 return; 7501 } 7502 7503 // Strip off any parens and casts. 7504 StringLiteral *SL = dyn_cast<StringLiteral>(SrcExpr->IgnoreParenCasts()); 7505 if (!SL || SL->isWide()) 7506 return; 7507 7508 Hint = FixItHint::CreateInsertion(SL->getLocStart(), "@"); 7509} 7510 7511bool Sema::DiagnoseAssignmentResult(AssignConvertType ConvTy, 7512 SourceLocation Loc, 7513 QualType DstType, QualType SrcType, 7514 Expr *SrcExpr, AssignmentAction Action, 7515 bool *Complained) { 7516 if (Complained) 7517 *Complained = false; 7518 7519 // Decode the result (notice that AST's are still created for extensions). 7520 bool isInvalid = false; 7521 unsigned DiagKind; 7522 FixItHint Hint; 7523 7524 switch (ConvTy) { 7525 default: assert(0 && "Unknown conversion type"); 7526 case Compatible: return false; 7527 case PointerToInt: 7528 DiagKind = diag::ext_typecheck_convert_pointer_int; 7529 break; 7530 case IntToPointer: 7531 DiagKind = diag::ext_typecheck_convert_int_pointer; 7532 break; 7533 case IncompatiblePointer: 7534 MakeObjCStringLiteralFixItHint(*this, DstType, SrcExpr, Hint); 7535 DiagKind = diag::ext_typecheck_convert_incompatible_pointer; 7536 break; 7537 case IncompatiblePointerSign: 7538 DiagKind = diag::ext_typecheck_convert_incompatible_pointer_sign; 7539 break; 7540 case FunctionVoidPointer: 7541 DiagKind = diag::ext_typecheck_convert_pointer_void_func; 7542 break; 7543 case CompatiblePointerDiscardsQualifiers: 7544 // If the qualifiers lost were because we were applying the 7545 // (deprecated) C++ conversion from a string literal to a char* 7546 // (or wchar_t*), then there was no error (C++ 4.2p2). FIXME: 7547 // Ideally, this check would be performed in 7548 // CheckPointerTypesForAssignment. However, that would require a 7549 // bit of refactoring (so that the second argument is an 7550 // expression, rather than a type), which should be done as part 7551 // of a larger effort to fix CheckPointerTypesForAssignment for 7552 // C++ semantics. 7553 if (getLangOptions().CPlusPlus && 7554 IsStringLiteralToNonConstPointerConversion(SrcExpr, DstType)) 7555 return false; 7556 DiagKind = diag::ext_typecheck_convert_discards_qualifiers; 7557 break; 7558 case IncompatibleNestedPointerQualifiers: 7559 DiagKind = diag::ext_nested_pointer_qualifier_mismatch; 7560 break; 7561 case IntToBlockPointer: 7562 DiagKind = diag::err_int_to_block_pointer; 7563 break; 7564 case IncompatibleBlockPointer: 7565 DiagKind = diag::err_typecheck_convert_incompatible_block_pointer; 7566 break; 7567 case IncompatibleObjCQualifiedId: 7568 // FIXME: Diagnose the problem in ObjCQualifiedIdTypesAreCompatible, since 7569 // it can give a more specific diagnostic. 7570 DiagKind = diag::warn_incompatible_qualified_id; 7571 break; 7572 case IncompatibleVectors: 7573 DiagKind = diag::warn_incompatible_vectors; 7574 break; 7575 case Incompatible: 7576 DiagKind = diag::err_typecheck_convert_incompatible; 7577 isInvalid = true; 7578 break; 7579 } 7580 7581 QualType FirstType, SecondType; 7582 switch (Action) { 7583 case AA_Assigning: 7584 case AA_Initializing: 7585 // The destination type comes first. 7586 FirstType = DstType; 7587 SecondType = SrcType; 7588 break; 7589 7590 case AA_Returning: 7591 case AA_Passing: 7592 case AA_Converting: 7593 case AA_Sending: 7594 case AA_Casting: 7595 // The source type comes first. 7596 FirstType = SrcType; 7597 SecondType = DstType; 7598 break; 7599 } 7600 7601 Diag(Loc, DiagKind) << FirstType << SecondType << Action 7602 << SrcExpr->getSourceRange() << Hint; 7603 if (Complained) 7604 *Complained = true; 7605 return isInvalid; 7606} 7607 7608bool Sema::VerifyIntegerConstantExpression(const Expr *E, llvm::APSInt *Result){ 7609 llvm::APSInt ICEResult; 7610 if (E->isIntegerConstantExpr(ICEResult, Context)) { 7611 if (Result) 7612 *Result = ICEResult; 7613 return false; 7614 } 7615 7616 Expr::EvalResult EvalResult; 7617 7618 if (!E->Evaluate(EvalResult, Context) || !EvalResult.Val.isInt() || 7619 EvalResult.HasSideEffects) { 7620 Diag(E->getExprLoc(), diag::err_expr_not_ice) << E->getSourceRange(); 7621 7622 if (EvalResult.Diag) { 7623 // We only show the note if it's not the usual "invalid subexpression" 7624 // or if it's actually in a subexpression. 7625 if (EvalResult.Diag != diag::note_invalid_subexpr_in_ice || 7626 E->IgnoreParens() != EvalResult.DiagExpr->IgnoreParens()) 7627 Diag(EvalResult.DiagLoc, EvalResult.Diag); 7628 } 7629 7630 return true; 7631 } 7632 7633 Diag(E->getExprLoc(), diag::ext_expr_not_ice) << 7634 E->getSourceRange(); 7635 7636 if (EvalResult.Diag && 7637 Diags.getDiagnosticLevel(diag::ext_expr_not_ice) != Diagnostic::Ignored) 7638 Diag(EvalResult.DiagLoc, EvalResult.Diag); 7639 7640 if (Result) 7641 *Result = EvalResult.Val.getInt(); 7642 return false; 7643} 7644 7645void 7646Sema::PushExpressionEvaluationContext(ExpressionEvaluationContext NewContext) { 7647 ExprEvalContexts.push_back( 7648 ExpressionEvaluationContextRecord(NewContext, ExprTemporaries.size())); 7649} 7650 7651void 7652Sema::PopExpressionEvaluationContext() { 7653 // Pop the current expression evaluation context off the stack. 7654 ExpressionEvaluationContextRecord Rec = ExprEvalContexts.back(); 7655 ExprEvalContexts.pop_back(); 7656 7657 if (Rec.Context == PotentiallyPotentiallyEvaluated) { 7658 if (Rec.PotentiallyReferenced) { 7659 // Mark any remaining declarations in the current position of the stack 7660 // as "referenced". If they were not meant to be referenced, semantic 7661 // analysis would have eliminated them (e.g., in ActOnCXXTypeId). 7662 for (PotentiallyReferencedDecls::iterator 7663 I = Rec.PotentiallyReferenced->begin(), 7664 IEnd = Rec.PotentiallyReferenced->end(); 7665 I != IEnd; ++I) 7666 MarkDeclarationReferenced(I->first, I->second); 7667 } 7668 7669 if (Rec.PotentiallyDiagnosed) { 7670 // Emit any pending diagnostics. 7671 for (PotentiallyEmittedDiagnostics::iterator 7672 I = Rec.PotentiallyDiagnosed->begin(), 7673 IEnd = Rec.PotentiallyDiagnosed->end(); 7674 I != IEnd; ++I) 7675 Diag(I->first, I->second); 7676 } 7677 } 7678 7679 // When are coming out of an unevaluated context, clear out any 7680 // temporaries that we may have created as part of the evaluation of 7681 // the expression in that context: they aren't relevant because they 7682 // will never be constructed. 7683 if (Rec.Context == Unevaluated && 7684 ExprTemporaries.size() > Rec.NumTemporaries) 7685 ExprTemporaries.erase(ExprTemporaries.begin() + Rec.NumTemporaries, 7686 ExprTemporaries.end()); 7687 7688 // Destroy the popped expression evaluation record. 7689 Rec.Destroy(); 7690} 7691 7692/// \brief Note that the given declaration was referenced in the source code. 7693/// 7694/// This routine should be invoke whenever a given declaration is referenced 7695/// in the source code, and where that reference occurred. If this declaration 7696/// reference means that the the declaration is used (C++ [basic.def.odr]p2, 7697/// C99 6.9p3), then the declaration will be marked as used. 7698/// 7699/// \param Loc the location where the declaration was referenced. 7700/// 7701/// \param D the declaration that has been referenced by the source code. 7702void Sema::MarkDeclarationReferenced(SourceLocation Loc, Decl *D) { 7703 assert(D && "No declaration?"); 7704 7705 if (D->isUsed(false)) 7706 return; 7707 7708 // Mark a parameter or variable declaration "used", regardless of whether we're in a 7709 // template or not. The reason for this is that unevaluated expressions 7710 // (e.g. (void)sizeof()) constitute a use for warning purposes (-Wunused-variables and 7711 // -Wunused-parameters) 7712 if (isa<ParmVarDecl>(D) || 7713 (isa<VarDecl>(D) && D->getDeclContext()->isFunctionOrMethod())) { 7714 D->setUsed(true); 7715 return; 7716 } 7717 7718 if (!isa<VarDecl>(D) && !isa<FunctionDecl>(D)) 7719 return; 7720 7721 // Do not mark anything as "used" within a dependent context; wait for 7722 // an instantiation. 7723 if (CurContext->isDependentContext()) 7724 return; 7725 7726 switch (ExprEvalContexts.back().Context) { 7727 case Unevaluated: 7728 // We are in an expression that is not potentially evaluated; do nothing. 7729 return; 7730 7731 case PotentiallyEvaluated: 7732 // We are in a potentially-evaluated expression, so this declaration is 7733 // "used"; handle this below. 7734 break; 7735 7736 case PotentiallyPotentiallyEvaluated: 7737 // We are in an expression that may be potentially evaluated; queue this 7738 // declaration reference until we know whether the expression is 7739 // potentially evaluated. 7740 ExprEvalContexts.back().addReferencedDecl(Loc, D); 7741 return; 7742 7743 case PotentiallyEvaluatedIfUsed: 7744 // Referenced declarations will only be used if the construct in the 7745 // containing expression is used. 7746 return; 7747 } 7748 7749 // Note that this declaration has been used. 7750 if (CXXConstructorDecl *Constructor = dyn_cast<CXXConstructorDecl>(D)) { 7751 unsigned TypeQuals; 7752 if (Constructor->isImplicit() && Constructor->isDefaultConstructor()) { 7753 if (Constructor->getParent()->hasTrivialConstructor()) 7754 return; 7755 if (!Constructor->isUsed(false)) 7756 DefineImplicitDefaultConstructor(Loc, Constructor); 7757 } else if (Constructor->isImplicit() && 7758 Constructor->isCopyConstructor(TypeQuals)) { 7759 if (!Constructor->isUsed(false)) 7760 DefineImplicitCopyConstructor(Loc, Constructor, TypeQuals); 7761 } 7762 7763 MarkVTableUsed(Loc, Constructor->getParent()); 7764 } else if (CXXDestructorDecl *Destructor = dyn_cast<CXXDestructorDecl>(D)) { 7765 if (Destructor->isImplicit() && !Destructor->isUsed(false)) 7766 DefineImplicitDestructor(Loc, Destructor); 7767 if (Destructor->isVirtual()) 7768 MarkVTableUsed(Loc, Destructor->getParent()); 7769 } else if (CXXMethodDecl *MethodDecl = dyn_cast<CXXMethodDecl>(D)) { 7770 if (MethodDecl->isImplicit() && MethodDecl->isOverloadedOperator() && 7771 MethodDecl->getOverloadedOperator() == OO_Equal) { 7772 if (!MethodDecl->isUsed(false)) 7773 DefineImplicitCopyAssignment(Loc, MethodDecl); 7774 } else if (MethodDecl->isVirtual()) 7775 MarkVTableUsed(Loc, MethodDecl->getParent()); 7776 } 7777 if (FunctionDecl *Function = dyn_cast<FunctionDecl>(D)) { 7778 // Implicit instantiation of function templates and member functions of 7779 // class templates. 7780 if (Function->isImplicitlyInstantiable()) { 7781 bool AlreadyInstantiated = false; 7782 if (FunctionTemplateSpecializationInfo *SpecInfo 7783 = Function->getTemplateSpecializationInfo()) { 7784 if (SpecInfo->getPointOfInstantiation().isInvalid()) 7785 SpecInfo->setPointOfInstantiation(Loc); 7786 else if (SpecInfo->getTemplateSpecializationKind() 7787 == TSK_ImplicitInstantiation) 7788 AlreadyInstantiated = true; 7789 } else if (MemberSpecializationInfo *MSInfo 7790 = Function->getMemberSpecializationInfo()) { 7791 if (MSInfo->getPointOfInstantiation().isInvalid()) 7792 MSInfo->setPointOfInstantiation(Loc); 7793 else if (MSInfo->getTemplateSpecializationKind() 7794 == TSK_ImplicitInstantiation) 7795 AlreadyInstantiated = true; 7796 } 7797 7798 if (!AlreadyInstantiated) { 7799 if (isa<CXXRecordDecl>(Function->getDeclContext()) && 7800 cast<CXXRecordDecl>(Function->getDeclContext())->isLocalClass()) 7801 PendingLocalImplicitInstantiations.push_back(std::make_pair(Function, 7802 Loc)); 7803 else 7804 PendingInstantiations.push_back(std::make_pair(Function, Loc)); 7805 } 7806 } else // Walk redefinitions, as some of them may be instantiable. 7807 for (FunctionDecl::redecl_iterator i(Function->redecls_begin()), 7808 e(Function->redecls_end()); i != e; ++i) { 7809 if (!i->isUsed(false) && i->isImplicitlyInstantiable()) 7810 MarkDeclarationReferenced(Loc, *i); 7811 } 7812 7813 // FIXME: keep track of references to static functions 7814 7815 // Recursive functions should be marked when used from another function. 7816 if (CurContext != Function) 7817 Function->setUsed(true); 7818 7819 return; 7820 } 7821 7822 if (VarDecl *Var = dyn_cast<VarDecl>(D)) { 7823 // Implicit instantiation of static data members of class templates. 7824 if (Var->isStaticDataMember() && 7825 Var->getInstantiatedFromStaticDataMember()) { 7826 MemberSpecializationInfo *MSInfo = Var->getMemberSpecializationInfo(); 7827 assert(MSInfo && "Missing member specialization information?"); 7828 if (MSInfo->getPointOfInstantiation().isInvalid() && 7829 MSInfo->getTemplateSpecializationKind()== TSK_ImplicitInstantiation) { 7830 MSInfo->setPointOfInstantiation(Loc); 7831 PendingInstantiations.push_back(std::make_pair(Var, Loc)); 7832 } 7833 } 7834 7835 // FIXME: keep track of references to static data? 7836 7837 D->setUsed(true); 7838 return; 7839 } 7840} 7841 7842namespace { 7843 // Mark all of the declarations referenced 7844 // FIXME: Not fully implemented yet! We need to have a better understanding 7845 // of when we're entering 7846 class MarkReferencedDecls : public RecursiveASTVisitor<MarkReferencedDecls> { 7847 Sema &S; 7848 SourceLocation Loc; 7849 7850 public: 7851 typedef RecursiveASTVisitor<MarkReferencedDecls> Inherited; 7852 7853 MarkReferencedDecls(Sema &S, SourceLocation Loc) : S(S), Loc(Loc) { } 7854 7855 bool TraverseTemplateArgument(const TemplateArgument &Arg); 7856 bool TraverseRecordType(RecordType *T); 7857 }; 7858} 7859 7860bool MarkReferencedDecls::TraverseTemplateArgument( 7861 const TemplateArgument &Arg) { 7862 if (Arg.getKind() == TemplateArgument::Declaration) { 7863 S.MarkDeclarationReferenced(Loc, Arg.getAsDecl()); 7864 } 7865 7866 return Inherited::TraverseTemplateArgument(Arg); 7867} 7868 7869bool MarkReferencedDecls::TraverseRecordType(RecordType *T) { 7870 if (ClassTemplateSpecializationDecl *Spec 7871 = dyn_cast<ClassTemplateSpecializationDecl>(T->getDecl())) { 7872 const TemplateArgumentList &Args = Spec->getTemplateArgs(); 7873 return TraverseTemplateArguments(Args.getFlatArgumentList(), 7874 Args.flat_size()); 7875 } 7876 7877 return true; 7878} 7879 7880void Sema::MarkDeclarationsReferencedInType(SourceLocation Loc, QualType T) { 7881 MarkReferencedDecls Marker(*this, Loc); 7882 Marker.TraverseType(Context.getCanonicalType(T)); 7883} 7884 7885namespace { 7886 /// \brief Helper class that marks all of the declarations referenced by 7887 /// potentially-evaluated subexpressions as "referenced". 7888 class EvaluatedExprMarker : public EvaluatedExprVisitor<EvaluatedExprMarker> { 7889 Sema &S; 7890 7891 public: 7892 typedef EvaluatedExprVisitor<EvaluatedExprMarker> Inherited; 7893 7894 explicit EvaluatedExprMarker(Sema &S) : Inherited(S.Context), S(S) { } 7895 7896 void VisitDeclRefExpr(DeclRefExpr *E) { 7897 S.MarkDeclarationReferenced(E->getLocation(), E->getDecl()); 7898 } 7899 7900 void VisitMemberExpr(MemberExpr *E) { 7901 S.MarkDeclarationReferenced(E->getMemberLoc(), E->getMemberDecl()); 7902 Inherited::VisitMemberExpr(E); 7903 } 7904 7905 void VisitCXXNewExpr(CXXNewExpr *E) { 7906 if (E->getConstructor()) 7907 S.MarkDeclarationReferenced(E->getLocStart(), E->getConstructor()); 7908 if (E->getOperatorNew()) 7909 S.MarkDeclarationReferenced(E->getLocStart(), E->getOperatorNew()); 7910 if (E->getOperatorDelete()) 7911 S.MarkDeclarationReferenced(E->getLocStart(), E->getOperatorDelete()); 7912 Inherited::VisitCXXNewExpr(E); 7913 } 7914 7915 void VisitCXXDeleteExpr(CXXDeleteExpr *E) { 7916 if (E->getOperatorDelete()) 7917 S.MarkDeclarationReferenced(E->getLocStart(), E->getOperatorDelete()); 7918 QualType Destroyed = S.Context.getBaseElementType(E->getDestroyedType()); 7919 if (const RecordType *DestroyedRec = Destroyed->getAs<RecordType>()) { 7920 CXXRecordDecl *Record = cast<CXXRecordDecl>(DestroyedRec->getDecl()); 7921 S.MarkDeclarationReferenced(E->getLocStart(), 7922 S.LookupDestructor(Record)); 7923 } 7924 7925 Inherited::VisitCXXDeleteExpr(E); 7926 } 7927 7928 void VisitCXXConstructExpr(CXXConstructExpr *E) { 7929 S.MarkDeclarationReferenced(E->getLocStart(), E->getConstructor()); 7930 Inherited::VisitCXXConstructExpr(E); 7931 } 7932 7933 void VisitBlockDeclRefExpr(BlockDeclRefExpr *E) { 7934 S.MarkDeclarationReferenced(E->getLocation(), E->getDecl()); 7935 } 7936 }; 7937} 7938 7939/// \brief Mark any declarations that appear within this expression or any 7940/// potentially-evaluated subexpressions as "referenced". 7941void Sema::MarkDeclarationsReferencedInExpr(Expr *E) { 7942 EvaluatedExprMarker(*this).Visit(E); 7943} 7944 7945/// \brief Emit a diagnostic that describes an effect on the run-time behavior 7946/// of the program being compiled. 7947/// 7948/// This routine emits the given diagnostic when the code currently being 7949/// type-checked is "potentially evaluated", meaning that there is a 7950/// possibility that the code will actually be executable. Code in sizeof() 7951/// expressions, code used only during overload resolution, etc., are not 7952/// potentially evaluated. This routine will suppress such diagnostics or, 7953/// in the absolutely nutty case of potentially potentially evaluated 7954/// expressions (C++ typeid), queue the diagnostic to potentially emit it 7955/// later. 7956/// 7957/// This routine should be used for all diagnostics that describe the run-time 7958/// behavior of a program, such as passing a non-POD value through an ellipsis. 7959/// Failure to do so will likely result in spurious diagnostics or failures 7960/// during overload resolution or within sizeof/alignof/typeof/typeid. 7961bool Sema::DiagRuntimeBehavior(SourceLocation Loc, 7962 const PartialDiagnostic &PD) { 7963 switch (ExprEvalContexts.back().Context ) { 7964 case Unevaluated: 7965 // The argument will never be evaluated, so don't complain. 7966 break; 7967 7968 case PotentiallyEvaluated: 7969 case PotentiallyEvaluatedIfUsed: 7970 Diag(Loc, PD); 7971 return true; 7972 7973 case PotentiallyPotentiallyEvaluated: 7974 ExprEvalContexts.back().addDiagnostic(Loc, PD); 7975 break; 7976 } 7977 7978 return false; 7979} 7980 7981bool Sema::CheckCallReturnType(QualType ReturnType, SourceLocation Loc, 7982 CallExpr *CE, FunctionDecl *FD) { 7983 if (ReturnType->isVoidType() || !ReturnType->isIncompleteType()) 7984 return false; 7985 7986 PartialDiagnostic Note = 7987 FD ? PDiag(diag::note_function_with_incomplete_return_type_declared_here) 7988 << FD->getDeclName() : PDiag(); 7989 SourceLocation NoteLoc = FD ? FD->getLocation() : SourceLocation(); 7990 7991 if (RequireCompleteType(Loc, ReturnType, 7992 FD ? 7993 PDiag(diag::err_call_function_incomplete_return) 7994 << CE->getSourceRange() << FD->getDeclName() : 7995 PDiag(diag::err_call_incomplete_return) 7996 << CE->getSourceRange(), 7997 std::make_pair(NoteLoc, Note))) 7998 return true; 7999 8000 return false; 8001} 8002 8003// Diagnose the common s/=/==/ typo. Note that adding parentheses 8004// will prevent this condition from triggering, which is what we want. 8005void Sema::DiagnoseAssignmentAsCondition(Expr *E) { 8006 SourceLocation Loc; 8007 8008 unsigned diagnostic = diag::warn_condition_is_assignment; 8009 8010 if (isa<BinaryOperator>(E)) { 8011 BinaryOperator *Op = cast<BinaryOperator>(E); 8012 if (Op->getOpcode() != BO_Assign) 8013 return; 8014 8015 // Greylist some idioms by putting them into a warning subcategory. 8016 if (ObjCMessageExpr *ME 8017 = dyn_cast<ObjCMessageExpr>(Op->getRHS()->IgnoreParenCasts())) { 8018 Selector Sel = ME->getSelector(); 8019 8020 // self = [<foo> init...] 8021 if (isSelfExpr(Op->getLHS()) 8022 && Sel.getIdentifierInfoForSlot(0)->getName().startswith("init")) 8023 diagnostic = diag::warn_condition_is_idiomatic_assignment; 8024 8025 // <foo> = [<bar> nextObject] 8026 else if (Sel.isUnarySelector() && 8027 Sel.getIdentifierInfoForSlot(0)->getName() == "nextObject") 8028 diagnostic = diag::warn_condition_is_idiomatic_assignment; 8029 } 8030 8031 Loc = Op->getOperatorLoc(); 8032 } else if (isa<CXXOperatorCallExpr>(E)) { 8033 CXXOperatorCallExpr *Op = cast<CXXOperatorCallExpr>(E); 8034 if (Op->getOperator() != OO_Equal) 8035 return; 8036 8037 Loc = Op->getOperatorLoc(); 8038 } else { 8039 // Not an assignment. 8040 return; 8041 } 8042 8043 SourceLocation Open = E->getSourceRange().getBegin(); 8044 SourceLocation Close = PP.getLocForEndOfToken(E->getSourceRange().getEnd()); 8045 8046 Diag(Loc, diagnostic) << E->getSourceRange(); 8047 Diag(Loc, diag::note_condition_assign_to_comparison) 8048 << FixItHint::CreateReplacement(Loc, "=="); 8049 Diag(Loc, diag::note_condition_assign_silence) 8050 << FixItHint::CreateInsertion(Open, "(") 8051 << FixItHint::CreateInsertion(Close, ")"); 8052} 8053 8054bool Sema::CheckBooleanCondition(Expr *&E, SourceLocation Loc) { 8055 DiagnoseAssignmentAsCondition(E); 8056 8057 if (!E->isTypeDependent()) { 8058 DefaultFunctionArrayLvalueConversion(E); 8059 8060 QualType T = E->getType(); 8061 8062 if (getLangOptions().CPlusPlus) { 8063 if (CheckCXXBooleanCondition(E)) // C++ 6.4p4 8064 return true; 8065 } else if (!T->isScalarType()) { // C99 6.8.4.1p1 8066 Diag(Loc, diag::err_typecheck_statement_requires_scalar) 8067 << T << E->getSourceRange(); 8068 return true; 8069 } 8070 } 8071 8072 return false; 8073} 8074 8075ExprResult Sema::ActOnBooleanCondition(Scope *S, SourceLocation Loc, 8076 Expr *Sub) { 8077 if (!Sub) 8078 return ExprError(); 8079 8080 if (CheckBooleanCondition(Sub, Loc)) 8081 return ExprError(); 8082 8083 return Owned(Sub); 8084} 8085