SemaExpr.cpp revision d6a9427b13d3f1d5762de2d683268821c7853fdd
1//===--- SemaExpr.cpp - Semantic Analysis for Expressions -----------------===// 2// 3// The LLVM Compiler Infrastructure 4// 5// This file is distributed under the University of Illinois Open Source 6// License. See LICENSE.TXT for details. 7// 8//===----------------------------------------------------------------------===// 9// 10// This file implements semantic analysis for expressions. 11// 12//===----------------------------------------------------------------------===// 13 14#include "Sema.h" 15#include "SemaInit.h" 16#include "Lookup.h" 17#include "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/Expr.h" 23#include "clang/AST/ExprCXX.h" 24#include "clang/AST/ExprObjC.h" 25#include "clang/AST/RecursiveASTVisitor.h" 26#include "clang/AST/TypeLoc.h" 27#include "clang/Basic/PartialDiagnostic.h" 28#include "clang/Basic/SourceManager.h" 29#include "clang/Basic/TargetInfo.h" 30#include "clang/Lex/LiteralSupport.h" 31#include "clang/Lex/Preprocessor.h" 32#include "clang/Parse/DeclSpec.h" 33#include "clang/Parse/Designator.h" 34#include "clang/Parse/Scope.h" 35#include "clang/Parse/Template.h" 36using namespace clang; 37 38 39/// \brief Determine whether the use of this declaration is valid, and 40/// emit any corresponding diagnostics. 41/// 42/// This routine diagnoses various problems with referencing 43/// declarations that can occur when using a declaration. For example, 44/// it might warn if a deprecated or unavailable declaration is being 45/// used, or produce an error (and return true) if a C++0x deleted 46/// function is being used. 47/// 48/// If IgnoreDeprecated is set to true, this should not want about deprecated 49/// decls. 50/// 51/// \returns true if there was an error (this declaration cannot be 52/// referenced), false otherwise. 53/// 54bool Sema::DiagnoseUseOfDecl(NamedDecl *D, SourceLocation Loc) { 55 // See if the decl is deprecated. 56 if (D->getAttr<DeprecatedAttr>()) { 57 EmitDeprecationWarning(D, Loc); 58 } 59 60 // See if the decl is unavailable 61 if (D->getAttr<UnavailableAttr>()) { 62 Diag(Loc, diag::warn_unavailable) << D->getDeclName(); 63 Diag(D->getLocation(), diag::note_unavailable_here) << 0; 64 } 65 66 // See if this is a deleted function. 67 if (FunctionDecl *FD = dyn_cast<FunctionDecl>(D)) { 68 if (FD->isDeleted()) { 69 Diag(Loc, diag::err_deleted_function_use); 70 Diag(D->getLocation(), diag::note_unavailable_here) << true; 71 return true; 72 } 73 } 74 75 return false; 76} 77 78/// DiagnoseSentinelCalls - This routine checks on method dispatch calls 79/// (and other functions in future), which have been declared with sentinel 80/// attribute. It warns if call does not have the sentinel argument. 81/// 82void Sema::DiagnoseSentinelCalls(NamedDecl *D, SourceLocation Loc, 83 Expr **Args, unsigned NumArgs) { 84 const SentinelAttr *attr = D->getAttr<SentinelAttr>(); 85 if (!attr) 86 return; 87 88 // FIXME: In C++0x, if any of the arguments are parameter pack 89 // expansions, we can't check for the sentinel now. 90 int sentinelPos = attr->getSentinel(); 91 int nullPos = attr->getNullPos(); 92 93 // FIXME. ObjCMethodDecl and FunctionDecl need be derived from the same common 94 // base class. Then we won't be needing two versions of the same code. 95 unsigned int i = 0; 96 bool warnNotEnoughArgs = false; 97 int isMethod = 0; 98 if (ObjCMethodDecl *MD = dyn_cast<ObjCMethodDecl>(D)) { 99 // skip over named parameters. 100 ObjCMethodDecl::param_iterator P, E = MD->param_end(); 101 for (P = MD->param_begin(); (P != E && i < NumArgs); ++P) { 102 if (nullPos) 103 --nullPos; 104 else 105 ++i; 106 } 107 warnNotEnoughArgs = (P != E || i >= NumArgs); 108 isMethod = 1; 109 } else if (FunctionDecl *FD = dyn_cast<FunctionDecl>(D)) { 110 // skip over named parameters. 111 ObjCMethodDecl::param_iterator P, E = FD->param_end(); 112 for (P = FD->param_begin(); (P != E && i < NumArgs); ++P) { 113 if (nullPos) 114 --nullPos; 115 else 116 ++i; 117 } 118 warnNotEnoughArgs = (P != E || i >= NumArgs); 119 } else if (VarDecl *V = dyn_cast<VarDecl>(D)) { 120 // block or function pointer call. 121 QualType Ty = V->getType(); 122 if (Ty->isBlockPointerType() || Ty->isFunctionPointerType()) { 123 const FunctionType *FT = Ty->isFunctionPointerType() 124 ? Ty->getAs<PointerType>()->getPointeeType()->getAs<FunctionType>() 125 : Ty->getAs<BlockPointerType>()->getPointeeType()->getAs<FunctionType>(); 126 if (const FunctionProtoType *Proto = dyn_cast<FunctionProtoType>(FT)) { 127 unsigned NumArgsInProto = Proto->getNumArgs(); 128 unsigned k; 129 for (k = 0; (k != NumArgsInProto && i < NumArgs); k++) { 130 if (nullPos) 131 --nullPos; 132 else 133 ++i; 134 } 135 warnNotEnoughArgs = (k != NumArgsInProto || i >= NumArgs); 136 } 137 if (Ty->isBlockPointerType()) 138 isMethod = 2; 139 } else 140 return; 141 } else 142 return; 143 144 if (warnNotEnoughArgs) { 145 Diag(Loc, diag::warn_not_enough_argument) << D->getDeclName(); 146 Diag(D->getLocation(), diag::note_sentinel_here) << isMethod; 147 return; 148 } 149 int sentinel = i; 150 while (sentinelPos > 0 && i < NumArgs-1) { 151 --sentinelPos; 152 ++i; 153 } 154 if (sentinelPos > 0) { 155 Diag(Loc, diag::warn_not_enough_argument) << D->getDeclName(); 156 Diag(D->getLocation(), diag::note_sentinel_here) << isMethod; 157 return; 158 } 159 while (i < NumArgs-1) { 160 ++i; 161 ++sentinel; 162 } 163 Expr *sentinelExpr = Args[sentinel]; 164 if (!sentinelExpr) return; 165 if (sentinelExpr->isTypeDependent()) return; 166 if (sentinelExpr->isValueDependent()) return; 167 if (sentinelExpr->getType()->isPointerType() && 168 sentinelExpr->IgnoreParenCasts()->isNullPointerConstant(Context, 169 Expr::NPC_ValueDependentIsNull)) 170 return; 171 172 // Unfortunately, __null has type 'int'. 173 if (isa<GNUNullExpr>(sentinelExpr)) return; 174 175 Diag(Loc, diag::warn_missing_sentinel) << isMethod; 176 Diag(D->getLocation(), diag::note_sentinel_here) << isMethod; 177} 178 179SourceRange Sema::getExprRange(ExprTy *E) const { 180 Expr *Ex = (Expr *)E; 181 return Ex? Ex->getSourceRange() : SourceRange(); 182} 183 184//===----------------------------------------------------------------------===// 185// Standard Promotions and Conversions 186//===----------------------------------------------------------------------===// 187 188/// DefaultFunctionArrayConversion (C99 6.3.2.1p3, C99 6.3.2.1p4). 189void Sema::DefaultFunctionArrayConversion(Expr *&E) { 190 QualType Ty = E->getType(); 191 assert(!Ty.isNull() && "DefaultFunctionArrayConversion - missing type"); 192 193 if (Ty->isFunctionType()) 194 ImpCastExprToType(E, Context.getPointerType(Ty), 195 CastExpr::CK_FunctionToPointerDecay); 196 else if (Ty->isArrayType()) { 197 // In C90 mode, arrays only promote to pointers if the array expression is 198 // an lvalue. The relevant legalese is C90 6.2.2.1p3: "an lvalue that has 199 // type 'array of type' is converted to an expression that has type 'pointer 200 // to type'...". In C99 this was changed to: C99 6.3.2.1p3: "an expression 201 // that has type 'array of type' ...". The relevant change is "an lvalue" 202 // (C90) to "an expression" (C99). 203 // 204 // C++ 4.2p1: 205 // An lvalue or rvalue of type "array of N T" or "array of unknown bound of 206 // T" can be converted to an rvalue of type "pointer to T". 207 // 208 if (getLangOptions().C99 || getLangOptions().CPlusPlus || 209 E->isLvalue(Context) == Expr::LV_Valid) 210 ImpCastExprToType(E, Context.getArrayDecayedType(Ty), 211 CastExpr::CK_ArrayToPointerDecay); 212 } 213} 214 215void Sema::DefaultFunctionArrayLvalueConversion(Expr *&E) { 216 DefaultFunctionArrayConversion(E); 217 218 QualType Ty = E->getType(); 219 assert(!Ty.isNull() && "DefaultFunctionArrayLvalueConversion - missing type"); 220 if (!Ty->isDependentType() && Ty.hasQualifiers() && 221 (!getLangOptions().CPlusPlus || !Ty->isRecordType()) && 222 E->isLvalue(Context) == Expr::LV_Valid) { 223 // C++ [conv.lval]p1: 224 // [...] If T is a non-class type, the type of the rvalue is the 225 // cv-unqualified version of T. Otherwise, the type of the 226 // rvalue is T 227 // 228 // C99 6.3.2.1p2: 229 // If the lvalue has qualified type, the value has the unqualified 230 // version of the type of the lvalue; otherwise, the value has the 231 // type of the lvalue. 232 ImpCastExprToType(E, Ty.getUnqualifiedType(), CastExpr::CK_NoOp); 233 } 234} 235 236 237/// UsualUnaryConversions - Performs various conversions that are common to most 238/// operators (C99 6.3). The conversions of array and function types are 239/// sometimes surpressed. For example, the array->pointer conversion doesn't 240/// apply if the array is an argument to the sizeof or address (&) operators. 241/// In these instances, this routine should *not* be called. 242Expr *Sema::UsualUnaryConversions(Expr *&Expr) { 243 QualType Ty = Expr->getType(); 244 assert(!Ty.isNull() && "UsualUnaryConversions - missing type"); 245 246 // C99 6.3.1.1p2: 247 // 248 // The following may be used in an expression wherever an int or 249 // unsigned int may be used: 250 // - an object or expression with an integer type whose integer 251 // conversion rank is less than or equal to the rank of int 252 // and unsigned int. 253 // - A bit-field of type _Bool, int, signed int, or unsigned int. 254 // 255 // If an int can represent all values of the original type, the 256 // value is converted to an int; otherwise, it is converted to an 257 // unsigned int. These are called the integer promotions. All 258 // other types are unchanged by the integer promotions. 259 QualType PTy = Context.isPromotableBitField(Expr); 260 if (!PTy.isNull()) { 261 ImpCastExprToType(Expr, PTy, CastExpr::CK_IntegralCast); 262 return Expr; 263 } 264 if (Ty->isPromotableIntegerType()) { 265 QualType PT = Context.getPromotedIntegerType(Ty); 266 ImpCastExprToType(Expr, PT, CastExpr::CK_IntegralCast); 267 return Expr; 268 } 269 270 DefaultFunctionArrayLvalueConversion(Expr); 271 return Expr; 272} 273 274/// DefaultArgumentPromotion (C99 6.5.2.2p6). Used for function calls that 275/// do not have a prototype. Arguments that have type float are promoted to 276/// double. All other argument types are converted by UsualUnaryConversions(). 277void Sema::DefaultArgumentPromotion(Expr *&Expr) { 278 QualType Ty = Expr->getType(); 279 assert(!Ty.isNull() && "DefaultArgumentPromotion - missing type"); 280 281 // If this is a 'float' (CVR qualified or typedef) promote to double. 282 if (Ty->isSpecificBuiltinType(BuiltinType::Float)) 283 return ImpCastExprToType(Expr, Context.DoubleTy, 284 CastExpr::CK_FloatingCast); 285 286 UsualUnaryConversions(Expr); 287} 288 289/// DefaultVariadicArgumentPromotion - Like DefaultArgumentPromotion, but 290/// will warn if the resulting type is not a POD type, and rejects ObjC 291/// interfaces passed by value. This returns true if the argument type is 292/// completely illegal. 293bool Sema::DefaultVariadicArgumentPromotion(Expr *&Expr, VariadicCallType CT, 294 FunctionDecl *FDecl) { 295 DefaultArgumentPromotion(Expr); 296 297 // __builtin_va_start takes the second argument as a "varargs" argument, but 298 // it doesn't actually do anything with it. It doesn't need to be non-pod 299 // etc. 300 if (FDecl && FDecl->getBuiltinID() == Builtin::BI__builtin_va_start) 301 return false; 302 303 if (Expr->getType()->isObjCObjectType() && 304 DiagRuntimeBehavior(Expr->getLocStart(), 305 PDiag(diag::err_cannot_pass_objc_interface_to_vararg) 306 << Expr->getType() << CT)) 307 return true; 308 309 if (!Expr->getType()->isPODType() && 310 DiagRuntimeBehavior(Expr->getLocStart(), 311 PDiag(diag::warn_cannot_pass_non_pod_arg_to_vararg) 312 << Expr->getType() << CT)) 313 return true; 314 315 return false; 316} 317 318 319/// UsualArithmeticConversions - Performs various conversions that are common to 320/// binary operators (C99 6.3.1.8). If both operands aren't arithmetic, this 321/// routine returns the first non-arithmetic type found. The client is 322/// responsible for emitting appropriate error diagnostics. 323/// FIXME: verify the conversion rules for "complex int" are consistent with 324/// GCC. 325QualType Sema::UsualArithmeticConversions(Expr *&lhsExpr, Expr *&rhsExpr, 326 bool isCompAssign) { 327 if (!isCompAssign) 328 UsualUnaryConversions(lhsExpr); 329 330 UsualUnaryConversions(rhsExpr); 331 332 // For conversion purposes, we ignore any qualifiers. 333 // For example, "const float" and "float" are equivalent. 334 QualType lhs = 335 Context.getCanonicalType(lhsExpr->getType()).getUnqualifiedType(); 336 QualType rhs = 337 Context.getCanonicalType(rhsExpr->getType()).getUnqualifiedType(); 338 339 // If both types are identical, no conversion is needed. 340 if (lhs == rhs) 341 return lhs; 342 343 // If either side is a non-arithmetic type (e.g. a pointer), we are done. 344 // The caller can deal with this (e.g. pointer + int). 345 if (!lhs->isArithmeticType() || !rhs->isArithmeticType()) 346 return lhs; 347 348 // Perform bitfield promotions. 349 QualType LHSBitfieldPromoteTy = Context.isPromotableBitField(lhsExpr); 350 if (!LHSBitfieldPromoteTy.isNull()) 351 lhs = LHSBitfieldPromoteTy; 352 QualType RHSBitfieldPromoteTy = Context.isPromotableBitField(rhsExpr); 353 if (!RHSBitfieldPromoteTy.isNull()) 354 rhs = RHSBitfieldPromoteTy; 355 356 QualType destType = Context.UsualArithmeticConversionsType(lhs, rhs); 357 if (!isCompAssign) 358 ImpCastExprToType(lhsExpr, destType, CastExpr::CK_Unknown); 359 ImpCastExprToType(rhsExpr, destType, CastExpr::CK_Unknown); 360 return destType; 361} 362 363//===----------------------------------------------------------------------===// 364// Semantic Analysis for various Expression Types 365//===----------------------------------------------------------------------===// 366 367 368/// ActOnStringLiteral - The specified tokens were lexed as pasted string 369/// fragments (e.g. "foo" "bar" L"baz"). The result string has to handle string 370/// concatenation ([C99 5.1.1.2, translation phase #6]), so it may come from 371/// multiple tokens. However, the common case is that StringToks points to one 372/// string. 373/// 374Action::OwningExprResult 375Sema::ActOnStringLiteral(const Token *StringToks, unsigned NumStringToks) { 376 assert(NumStringToks && "Must have at least one string!"); 377 378 StringLiteralParser Literal(StringToks, NumStringToks, PP); 379 if (Literal.hadError) 380 return ExprError(); 381 382 llvm::SmallVector<SourceLocation, 4> StringTokLocs; 383 for (unsigned i = 0; i != NumStringToks; ++i) 384 StringTokLocs.push_back(StringToks[i].getLocation()); 385 386 QualType StrTy = Context.CharTy; 387 if (Literal.AnyWide) StrTy = Context.getWCharType(); 388 if (Literal.Pascal) StrTy = Context.UnsignedCharTy; 389 390 // A C++ string literal has a const-qualified element type (C++ 2.13.4p1). 391 if (getLangOptions().CPlusPlus || getLangOptions().ConstStrings ) 392 StrTy.addConst(); 393 394 // Get an array type for the string, according to C99 6.4.5. This includes 395 // the nul terminator character as well as the string length for pascal 396 // strings. 397 StrTy = Context.getConstantArrayType(StrTy, 398 llvm::APInt(32, Literal.GetNumStringChars()+1), 399 ArrayType::Normal, 0); 400 401 // Pass &StringTokLocs[0], StringTokLocs.size() to factory! 402 return Owned(StringLiteral::Create(Context, Literal.GetString(), 403 Literal.GetStringLength(), 404 Literal.AnyWide, StrTy, 405 &StringTokLocs[0], 406 StringTokLocs.size())); 407} 408 409/// ShouldSnapshotBlockValueReference - Return true if a reference inside of 410/// CurBlock to VD should cause it to be snapshotted (as we do for auto 411/// variables defined outside the block) or false if this is not needed (e.g. 412/// for values inside the block or for globals). 413/// 414/// This also keeps the 'hasBlockDeclRefExprs' in the BlockScopeInfo records 415/// up-to-date. 416/// 417static bool ShouldSnapshotBlockValueReference(Sema &S, BlockScopeInfo *CurBlock, 418 ValueDecl *VD) { 419 // If the value is defined inside the block, we couldn't snapshot it even if 420 // we wanted to. 421 if (CurBlock->TheDecl == VD->getDeclContext()) 422 return false; 423 424 // If this is an enum constant or function, it is constant, don't snapshot. 425 if (isa<EnumConstantDecl>(VD) || isa<FunctionDecl>(VD)) 426 return false; 427 428 // If this is a reference to an extern, static, or global variable, no need to 429 // snapshot it. 430 // FIXME: What about 'const' variables in C++? 431 if (const VarDecl *Var = dyn_cast<VarDecl>(VD)) 432 if (!Var->hasLocalStorage()) 433 return false; 434 435 // Blocks that have these can't be constant. 436 CurBlock->hasBlockDeclRefExprs = true; 437 438 // If we have nested blocks, the decl may be declared in an outer block (in 439 // which case that outer block doesn't get "hasBlockDeclRefExprs") or it may 440 // be defined outside all of the current blocks (in which case the blocks do 441 // all get the bit). Walk the nesting chain. 442 for (unsigned I = S.FunctionScopes.size() - 1; I; --I) { 443 BlockScopeInfo *NextBlock = dyn_cast<BlockScopeInfo>(S.FunctionScopes[I]); 444 445 if (!NextBlock) 446 continue; 447 448 // If we found the defining block for the variable, don't mark the block as 449 // having a reference outside it. 450 if (NextBlock->TheDecl == VD->getDeclContext()) 451 break; 452 453 // Otherwise, the DeclRef from the inner block causes the outer one to need 454 // a snapshot as well. 455 NextBlock->hasBlockDeclRefExprs = true; 456 } 457 458 return true; 459} 460 461 462 463/// BuildDeclRefExpr - Build a DeclRefExpr. 464Sema::OwningExprResult 465Sema::BuildDeclRefExpr(ValueDecl *D, QualType Ty, SourceLocation Loc, 466 const CXXScopeSpec *SS) { 467 if (Context.getCanonicalType(Ty) == Context.UndeducedAutoTy) { 468 Diag(Loc, 469 diag::err_auto_variable_cannot_appear_in_own_initializer) 470 << D->getDeclName(); 471 return ExprError(); 472 } 473 474 if (const VarDecl *VD = dyn_cast<VarDecl>(D)) { 475 if (isa<NonTypeTemplateParmDecl>(VD)) { 476 // Non-type template parameters can be referenced anywhere they are 477 // visible. 478 } else if (const CXXMethodDecl *MD = dyn_cast<CXXMethodDecl>(CurContext)) { 479 if (const FunctionDecl *FD = MD->getParent()->isLocalClass()) { 480 if (VD->hasLocalStorage() && VD->getDeclContext() != CurContext) { 481 Diag(Loc, diag::err_reference_to_local_var_in_enclosing_function) 482 << D->getIdentifier() << FD->getDeclName(); 483 Diag(D->getLocation(), diag::note_local_variable_declared_here) 484 << D->getIdentifier(); 485 return ExprError(); 486 } 487 } 488 } 489 } 490 491 MarkDeclarationReferenced(Loc, D); 492 493 return Owned(DeclRefExpr::Create(Context, 494 SS? (NestedNameSpecifier *)SS->getScopeRep() : 0, 495 SS? SS->getRange() : SourceRange(), 496 D, Loc, Ty)); 497} 498 499/// \brief Given a field that represents a member of an anonymous 500/// struct/union, build the path from that field's context to the 501/// actual member. 502/// 503/// Construct the sequence of field member references we'll have to 504/// perform to get to the field in the anonymous union/struct. The 505/// list of members is built from the field outward, so traverse it 506/// backwards to go from an object in the current context to the field 507/// we found. 508/// 509/// \returns The variable from which the field access should begin, 510/// for an anonymous struct/union that is not a member of another 511/// class. Otherwise, returns NULL. 512VarDecl *Sema::BuildAnonymousStructUnionMemberPath(FieldDecl *Field, 513 llvm::SmallVectorImpl<FieldDecl *> &Path) { 514 assert(Field->getDeclContext()->isRecord() && 515 cast<RecordDecl>(Field->getDeclContext())->isAnonymousStructOrUnion() 516 && "Field must be stored inside an anonymous struct or union"); 517 518 Path.push_back(Field); 519 VarDecl *BaseObject = 0; 520 DeclContext *Ctx = Field->getDeclContext(); 521 do { 522 RecordDecl *Record = cast<RecordDecl>(Ctx); 523 ValueDecl *AnonObject = Record->getAnonymousStructOrUnionObject(); 524 if (FieldDecl *AnonField = dyn_cast<FieldDecl>(AnonObject)) 525 Path.push_back(AnonField); 526 else { 527 BaseObject = cast<VarDecl>(AnonObject); 528 break; 529 } 530 Ctx = Ctx->getParent(); 531 } while (Ctx->isRecord() && 532 cast<RecordDecl>(Ctx)->isAnonymousStructOrUnion()); 533 534 return BaseObject; 535} 536 537Sema::OwningExprResult 538Sema::BuildAnonymousStructUnionMemberReference(SourceLocation Loc, 539 FieldDecl *Field, 540 Expr *BaseObjectExpr, 541 SourceLocation OpLoc) { 542 llvm::SmallVector<FieldDecl *, 4> AnonFields; 543 VarDecl *BaseObject = BuildAnonymousStructUnionMemberPath(Field, 544 AnonFields); 545 546 // Build the expression that refers to the base object, from 547 // which we will build a sequence of member references to each 548 // of the anonymous union objects and, eventually, the field we 549 // found via name lookup. 550 bool BaseObjectIsPointer = false; 551 Qualifiers BaseQuals; 552 if (BaseObject) { 553 // BaseObject is an anonymous struct/union variable (and is, 554 // therefore, not part of another non-anonymous record). 555 if (BaseObjectExpr) BaseObjectExpr->Destroy(Context); 556 MarkDeclarationReferenced(Loc, BaseObject); 557 BaseObjectExpr = new (Context) DeclRefExpr(BaseObject,BaseObject->getType(), 558 SourceLocation()); 559 BaseQuals 560 = Context.getCanonicalType(BaseObject->getType()).getQualifiers(); 561 } else if (BaseObjectExpr) { 562 // The caller provided the base object expression. Determine 563 // whether its a pointer and whether it adds any qualifiers to the 564 // anonymous struct/union fields we're looking into. 565 QualType ObjectType = BaseObjectExpr->getType(); 566 if (const PointerType *ObjectPtr = ObjectType->getAs<PointerType>()) { 567 BaseObjectIsPointer = true; 568 ObjectType = ObjectPtr->getPointeeType(); 569 } 570 BaseQuals 571 = Context.getCanonicalType(ObjectType).getQualifiers(); 572 } else { 573 // We've found a member of an anonymous struct/union that is 574 // inside a non-anonymous struct/union, so in a well-formed 575 // program our base object expression is "this". 576 DeclContext *DC = getFunctionLevelDeclContext(); 577 if (CXXMethodDecl *MD = dyn_cast<CXXMethodDecl>(DC)) { 578 if (!MD->isStatic()) { 579 QualType AnonFieldType 580 = Context.getTagDeclType( 581 cast<RecordDecl>(AnonFields.back()->getDeclContext())); 582 QualType ThisType = Context.getTagDeclType(MD->getParent()); 583 if ((Context.getCanonicalType(AnonFieldType) 584 == Context.getCanonicalType(ThisType)) || 585 IsDerivedFrom(ThisType, AnonFieldType)) { 586 // Our base object expression is "this". 587 BaseObjectExpr = new (Context) CXXThisExpr(Loc, 588 MD->getThisType(Context), 589 /*isImplicit=*/true); 590 BaseObjectIsPointer = true; 591 } 592 } else { 593 return ExprError(Diag(Loc,diag::err_invalid_member_use_in_static_method) 594 << Field->getDeclName()); 595 } 596 BaseQuals = Qualifiers::fromCVRMask(MD->getTypeQualifiers()); 597 } 598 599 if (!BaseObjectExpr) 600 return ExprError(Diag(Loc, diag::err_invalid_non_static_member_use) 601 << Field->getDeclName()); 602 } 603 604 // Build the implicit member references to the field of the 605 // anonymous struct/union. 606 Expr *Result = BaseObjectExpr; 607 Qualifiers ResultQuals = BaseQuals; 608 for (llvm::SmallVector<FieldDecl *, 4>::reverse_iterator 609 FI = AnonFields.rbegin(), FIEnd = AnonFields.rend(); 610 FI != FIEnd; ++FI) { 611 QualType MemberType = (*FI)->getType(); 612 Qualifiers MemberTypeQuals = 613 Context.getCanonicalType(MemberType).getQualifiers(); 614 615 // CVR attributes from the base are picked up by members, 616 // except that 'mutable' members don't pick up 'const'. 617 if ((*FI)->isMutable()) 618 ResultQuals.removeConst(); 619 620 // GC attributes are never picked up by members. 621 ResultQuals.removeObjCGCAttr(); 622 623 // TR 18037 does not allow fields to be declared with address spaces. 624 assert(!MemberTypeQuals.hasAddressSpace()); 625 626 Qualifiers NewQuals = ResultQuals + MemberTypeQuals; 627 if (NewQuals != MemberTypeQuals) 628 MemberType = Context.getQualifiedType(MemberType, NewQuals); 629 630 MarkDeclarationReferenced(Loc, *FI); 631 PerformObjectMemberConversion(Result, /*FIXME:Qualifier=*/0, *FI, *FI); 632 // FIXME: Might this end up being a qualified name? 633 Result = new (Context) MemberExpr(Result, BaseObjectIsPointer, *FI, 634 OpLoc, MemberType); 635 BaseObjectIsPointer = false; 636 ResultQuals = NewQuals; 637 } 638 639 return Owned(Result); 640} 641 642/// Decomposes the given name into a DeclarationName, its location, and 643/// possibly a list of template arguments. 644/// 645/// If this produces template arguments, it is permitted to call 646/// DecomposeTemplateName. 647/// 648/// This actually loses a lot of source location information for 649/// non-standard name kinds; we should consider preserving that in 650/// some way. 651static void DecomposeUnqualifiedId(Sema &SemaRef, 652 const UnqualifiedId &Id, 653 TemplateArgumentListInfo &Buffer, 654 DeclarationName &Name, 655 SourceLocation &NameLoc, 656 const TemplateArgumentListInfo *&TemplateArgs) { 657 if (Id.getKind() == UnqualifiedId::IK_TemplateId) { 658 Buffer.setLAngleLoc(Id.TemplateId->LAngleLoc); 659 Buffer.setRAngleLoc(Id.TemplateId->RAngleLoc); 660 661 ASTTemplateArgsPtr TemplateArgsPtr(SemaRef, 662 Id.TemplateId->getTemplateArgs(), 663 Id.TemplateId->NumArgs); 664 SemaRef.translateTemplateArguments(TemplateArgsPtr, Buffer); 665 TemplateArgsPtr.release(); 666 667 TemplateName TName = 668 Sema::TemplateTy::make(Id.TemplateId->Template).getAsVal<TemplateName>(); 669 670 Name = SemaRef.Context.getNameForTemplate(TName); 671 NameLoc = Id.TemplateId->TemplateNameLoc; 672 TemplateArgs = &Buffer; 673 } else { 674 Name = SemaRef.GetNameFromUnqualifiedId(Id); 675 NameLoc = Id.StartLocation; 676 TemplateArgs = 0; 677 } 678} 679 680/// Decompose the given template name into a list of lookup results. 681/// 682/// The unqualified ID must name a non-dependent template, which can 683/// be more easily tested by checking whether DecomposeUnqualifiedId 684/// found template arguments. 685static void DecomposeTemplateName(LookupResult &R, const UnqualifiedId &Id) { 686 assert(Id.getKind() == UnqualifiedId::IK_TemplateId); 687 TemplateName TName = 688 Sema::TemplateTy::make(Id.TemplateId->Template).getAsVal<TemplateName>(); 689 690 if (TemplateDecl *TD = TName.getAsTemplateDecl()) 691 R.addDecl(TD); 692 else if (OverloadedTemplateStorage *OT = TName.getAsOverloadedTemplate()) 693 for (OverloadedTemplateStorage::iterator I = OT->begin(), E = OT->end(); 694 I != E; ++I) 695 R.addDecl(*I); 696 697 R.resolveKind(); 698} 699 700/// Determines whether the given record is "fully-formed" at the given 701/// location, i.e. whether a qualified lookup into it is assured of 702/// getting consistent results already. 703static bool IsFullyFormedScope(Sema &SemaRef, CXXRecordDecl *Record) { 704 if (!Record->hasDefinition()) 705 return false; 706 707 for (CXXRecordDecl::base_class_iterator I = Record->bases_begin(), 708 E = Record->bases_end(); I != E; ++I) { 709 CanQualType BaseT = SemaRef.Context.getCanonicalType((*I).getType()); 710 CanQual<RecordType> BaseRT = BaseT->getAs<RecordType>(); 711 if (!BaseRT) return false; 712 713 CXXRecordDecl *BaseRecord = cast<CXXRecordDecl>(BaseRT->getDecl()); 714 if (!BaseRecord->hasDefinition() || 715 !IsFullyFormedScope(SemaRef, BaseRecord)) 716 return false; 717 } 718 719 return true; 720} 721 722/// Determines whether we can lookup this id-expression now or whether 723/// we have to wait until template instantiation is complete. 724static bool IsDependentIdExpression(Sema &SemaRef, const CXXScopeSpec &SS) { 725 DeclContext *DC = SemaRef.computeDeclContext(SS, false); 726 727 // If the qualifier scope isn't computable, it's definitely dependent. 728 if (!DC) return true; 729 730 // If the qualifier scope doesn't name a record, we can always look into it. 731 if (!isa<CXXRecordDecl>(DC)) return false; 732 733 // We can't look into record types unless they're fully-formed. 734 if (!IsFullyFormedScope(SemaRef, cast<CXXRecordDecl>(DC))) return true; 735 736 return false; 737} 738 739/// Determines if the given class is provably not derived from all of 740/// the prospective base classes. 741static bool IsProvablyNotDerivedFrom(Sema &SemaRef, 742 CXXRecordDecl *Record, 743 const llvm::SmallPtrSet<CXXRecordDecl*, 4> &Bases) { 744 if (Bases.count(Record->getCanonicalDecl())) 745 return false; 746 747 RecordDecl *RD = Record->getDefinition(); 748 if (!RD) return false; 749 Record = cast<CXXRecordDecl>(RD); 750 751 for (CXXRecordDecl::base_class_iterator I = Record->bases_begin(), 752 E = Record->bases_end(); I != E; ++I) { 753 CanQualType BaseT = SemaRef.Context.getCanonicalType((*I).getType()); 754 CanQual<RecordType> BaseRT = BaseT->getAs<RecordType>(); 755 if (!BaseRT) return false; 756 757 CXXRecordDecl *BaseRecord = cast<CXXRecordDecl>(BaseRT->getDecl()); 758 if (!IsProvablyNotDerivedFrom(SemaRef, BaseRecord, Bases)) 759 return false; 760 } 761 762 return true; 763} 764 765enum IMAKind { 766 /// The reference is definitely not an instance member access. 767 IMA_Static, 768 769 /// The reference may be an implicit instance member access. 770 IMA_Mixed, 771 772 /// The reference may be to an instance member, but it is invalid if 773 /// so, because the context is not an instance method. 774 IMA_Mixed_StaticContext, 775 776 /// The reference may be to an instance member, but it is invalid if 777 /// so, because the context is from an unrelated class. 778 IMA_Mixed_Unrelated, 779 780 /// The reference is definitely an implicit instance member access. 781 IMA_Instance, 782 783 /// The reference may be to an unresolved using declaration. 784 IMA_Unresolved, 785 786 /// The reference may be to an unresolved using declaration and the 787 /// context is not an instance method. 788 IMA_Unresolved_StaticContext, 789 790 /// The reference is to a member of an anonymous structure in a 791 /// non-class context. 792 IMA_AnonymousMember, 793 794 /// All possible referrents are instance members and the current 795 /// context is not an instance method. 796 IMA_Error_StaticContext, 797 798 /// All possible referrents are instance members of an unrelated 799 /// class. 800 IMA_Error_Unrelated 801}; 802 803/// The given lookup names class member(s) and is not being used for 804/// an address-of-member expression. Classify the type of access 805/// according to whether it's possible that this reference names an 806/// instance member. This is best-effort; it is okay to 807/// conservatively answer "yes", in which case some errors will simply 808/// not be caught until template-instantiation. 809static IMAKind ClassifyImplicitMemberAccess(Sema &SemaRef, 810 const LookupResult &R) { 811 assert(!R.empty() && (*R.begin())->isCXXClassMember()); 812 813 DeclContext *DC = SemaRef.getFunctionLevelDeclContext(); 814 bool isStaticContext = 815 (!isa<CXXMethodDecl>(DC) || 816 cast<CXXMethodDecl>(DC)->isStatic()); 817 818 if (R.isUnresolvableResult()) 819 return isStaticContext ? IMA_Unresolved_StaticContext : IMA_Unresolved; 820 821 // Collect all the declaring classes of instance members we find. 822 bool hasNonInstance = false; 823 llvm::SmallPtrSet<CXXRecordDecl*, 4> Classes; 824 for (LookupResult::iterator I = R.begin(), E = R.end(); I != E; ++I) { 825 NamedDecl *D = *I; 826 if (D->isCXXInstanceMember()) { 827 CXXRecordDecl *R = cast<CXXRecordDecl>(D->getDeclContext()); 828 829 // If this is a member of an anonymous record, move out to the 830 // innermost non-anonymous struct or union. If there isn't one, 831 // that's a special case. 832 while (R->isAnonymousStructOrUnion()) { 833 R = dyn_cast<CXXRecordDecl>(R->getParent()); 834 if (!R) return IMA_AnonymousMember; 835 } 836 Classes.insert(R->getCanonicalDecl()); 837 } 838 else 839 hasNonInstance = true; 840 } 841 842 // If we didn't find any instance members, it can't be an implicit 843 // member reference. 844 if (Classes.empty()) 845 return IMA_Static; 846 847 // If the current context is not an instance method, it can't be 848 // an implicit member reference. 849 if (isStaticContext) 850 return (hasNonInstance ? IMA_Mixed_StaticContext : IMA_Error_StaticContext); 851 852 // If we can prove that the current context is unrelated to all the 853 // declaring classes, it can't be an implicit member reference (in 854 // which case it's an error if any of those members are selected). 855 if (IsProvablyNotDerivedFrom(SemaRef, 856 cast<CXXMethodDecl>(DC)->getParent(), 857 Classes)) 858 return (hasNonInstance ? IMA_Mixed_Unrelated : IMA_Error_Unrelated); 859 860 return (hasNonInstance ? IMA_Mixed : IMA_Instance); 861} 862 863/// Diagnose a reference to a field with no object available. 864static void DiagnoseInstanceReference(Sema &SemaRef, 865 const CXXScopeSpec &SS, 866 const LookupResult &R) { 867 SourceLocation Loc = R.getNameLoc(); 868 SourceRange Range(Loc); 869 if (SS.isSet()) Range.setBegin(SS.getRange().getBegin()); 870 871 if (R.getAsSingle<FieldDecl>()) { 872 if (CXXMethodDecl *MD = dyn_cast<CXXMethodDecl>(SemaRef.CurContext)) { 873 if (MD->isStatic()) { 874 // "invalid use of member 'x' in static member function" 875 SemaRef.Diag(Loc, diag::err_invalid_member_use_in_static_method) 876 << Range << R.getLookupName(); 877 return; 878 } 879 } 880 881 SemaRef.Diag(Loc, diag::err_invalid_non_static_member_use) 882 << R.getLookupName() << Range; 883 return; 884 } 885 886 SemaRef.Diag(Loc, diag::err_member_call_without_object) << Range; 887} 888 889/// Diagnose an empty lookup. 890/// 891/// \return false if new lookup candidates were found 892bool Sema::DiagnoseEmptyLookup(Scope *S, CXXScopeSpec &SS, 893 LookupResult &R, CorrectTypoContext CTC) { 894 DeclarationName Name = R.getLookupName(); 895 896 unsigned diagnostic = diag::err_undeclared_var_use; 897 unsigned diagnostic_suggest = diag::err_undeclared_var_use_suggest; 898 if (Name.getNameKind() == DeclarationName::CXXOperatorName || 899 Name.getNameKind() == DeclarationName::CXXLiteralOperatorName || 900 Name.getNameKind() == DeclarationName::CXXConversionFunctionName) { 901 diagnostic = diag::err_undeclared_use; 902 diagnostic_suggest = diag::err_undeclared_use_suggest; 903 } 904 905 // If the original lookup was an unqualified lookup, fake an 906 // unqualified lookup. This is useful when (for example) the 907 // original lookup would not have found something because it was a 908 // dependent name. 909 for (DeclContext *DC = SS.isEmpty()? CurContext : 0; 910 DC; DC = DC->getParent()) { 911 if (isa<CXXRecordDecl>(DC)) { 912 LookupQualifiedName(R, DC); 913 914 if (!R.empty()) { 915 // Don't give errors about ambiguities in this lookup. 916 R.suppressDiagnostics(); 917 918 CXXMethodDecl *CurMethod = dyn_cast<CXXMethodDecl>(CurContext); 919 bool isInstance = CurMethod && 920 CurMethod->isInstance() && 921 DC == CurMethod->getParent(); 922 923 // Give a code modification hint to insert 'this->'. 924 // TODO: fixit for inserting 'Base<T>::' in the other cases. 925 // Actually quite difficult! 926 if (isInstance) 927 Diag(R.getNameLoc(), diagnostic) << Name 928 << FixItHint::CreateInsertion(R.getNameLoc(), "this->"); 929 else 930 Diag(R.getNameLoc(), diagnostic) << Name; 931 932 // Do we really want to note all of these? 933 for (LookupResult::iterator I = R.begin(), E = R.end(); I != E; ++I) 934 Diag((*I)->getLocation(), diag::note_dependent_var_use); 935 936 // Tell the callee to try to recover. 937 return false; 938 } 939 } 940 } 941 942 // We didn't find anything, so try to correct for a typo. 943 DeclarationName Corrected; 944 if (S && (Corrected = CorrectTypo(R, S, &SS, false, CTC))) { 945 if (!R.empty()) { 946 if (isa<ValueDecl>(*R.begin()) || isa<FunctionTemplateDecl>(*R.begin())) { 947 if (SS.isEmpty()) 948 Diag(R.getNameLoc(), diagnostic_suggest) << Name << R.getLookupName() 949 << FixItHint::CreateReplacement(R.getNameLoc(), 950 R.getLookupName().getAsString()); 951 else 952 Diag(R.getNameLoc(), diag::err_no_member_suggest) 953 << Name << computeDeclContext(SS, false) << R.getLookupName() 954 << SS.getRange() 955 << FixItHint::CreateReplacement(R.getNameLoc(), 956 R.getLookupName().getAsString()); 957 if (NamedDecl *ND = R.getAsSingle<NamedDecl>()) 958 Diag(ND->getLocation(), diag::note_previous_decl) 959 << ND->getDeclName(); 960 961 // Tell the callee to try to recover. 962 return false; 963 } 964 965 if (isa<TypeDecl>(*R.begin()) || isa<ObjCInterfaceDecl>(*R.begin())) { 966 // FIXME: If we ended up with a typo for a type name or 967 // Objective-C class name, we're in trouble because the parser 968 // is in the wrong place to recover. Suggest the typo 969 // correction, but don't make it a fix-it since we're not going 970 // to recover well anyway. 971 if (SS.isEmpty()) 972 Diag(R.getNameLoc(), diagnostic_suggest) << Name << R.getLookupName(); 973 else 974 Diag(R.getNameLoc(), diag::err_no_member_suggest) 975 << Name << computeDeclContext(SS, false) << R.getLookupName() 976 << SS.getRange(); 977 978 // Don't try to recover; it won't work. 979 return true; 980 } 981 } else { 982 // FIXME: We found a keyword. Suggest it, but don't provide a fix-it 983 // because we aren't able to recover. 984 if (SS.isEmpty()) 985 Diag(R.getNameLoc(), diagnostic_suggest) << Name << Corrected; 986 else 987 Diag(R.getNameLoc(), diag::err_no_member_suggest) 988 << Name << computeDeclContext(SS, false) << Corrected 989 << SS.getRange(); 990 return true; 991 } 992 R.clear(); 993 } 994 995 // Emit a special diagnostic for failed member lookups. 996 // FIXME: computing the declaration context might fail here (?) 997 if (!SS.isEmpty()) { 998 Diag(R.getNameLoc(), diag::err_no_member) 999 << Name << computeDeclContext(SS, false) 1000 << SS.getRange(); 1001 return true; 1002 } 1003 1004 // Give up, we can't recover. 1005 Diag(R.getNameLoc(), diagnostic) << Name; 1006 return true; 1007} 1008 1009Sema::OwningExprResult Sema::ActOnIdExpression(Scope *S, 1010 CXXScopeSpec &SS, 1011 UnqualifiedId &Id, 1012 bool HasTrailingLParen, 1013 bool isAddressOfOperand) { 1014 assert(!(isAddressOfOperand && HasTrailingLParen) && 1015 "cannot be direct & operand and have a trailing lparen"); 1016 1017 if (SS.isInvalid()) 1018 return ExprError(); 1019 1020 TemplateArgumentListInfo TemplateArgsBuffer; 1021 1022 // Decompose the UnqualifiedId into the following data. 1023 DeclarationName Name; 1024 SourceLocation NameLoc; 1025 const TemplateArgumentListInfo *TemplateArgs; 1026 DecomposeUnqualifiedId(*this, Id, TemplateArgsBuffer, 1027 Name, NameLoc, TemplateArgs); 1028 1029 IdentifierInfo *II = Name.getAsIdentifierInfo(); 1030 1031 // C++ [temp.dep.expr]p3: 1032 // An id-expression is type-dependent if it contains: 1033 // -- an identifier that was declared with a dependent type, 1034 // (note: handled after lookup) 1035 // -- a template-id that is dependent, 1036 // (note: handled in BuildTemplateIdExpr) 1037 // -- a conversion-function-id that specifies a dependent type, 1038 // -- a nested-name-specifier that contains a class-name that 1039 // names a dependent type. 1040 // Determine whether this is a member of an unknown specialization; 1041 // we need to handle these differently. 1042 if ((Name.getNameKind() == DeclarationName::CXXConversionFunctionName && 1043 Name.getCXXNameType()->isDependentType()) || 1044 (SS.isSet() && IsDependentIdExpression(*this, SS))) { 1045 return ActOnDependentIdExpression(SS, Name, NameLoc, 1046 isAddressOfOperand, 1047 TemplateArgs); 1048 } 1049 1050 // Perform the required lookup. 1051 LookupResult R(*this, Name, NameLoc, LookupOrdinaryName); 1052 if (TemplateArgs) { 1053 // Lookup the template name again to correctly establish the context in 1054 // which it was found. This is really unfortunate as we already did the 1055 // lookup to determine that it was a template name in the first place. If 1056 // this becomes a performance hit, we can work harder to preserve those 1057 // results until we get here but it's likely not worth it. 1058 bool MemberOfUnknownSpecialization; 1059 LookupTemplateName(R, S, SS, QualType(), /*EnteringContext=*/false, 1060 MemberOfUnknownSpecialization); 1061 } else { 1062 bool IvarLookupFollowUp = (!SS.isSet() && II && getCurMethodDecl()); 1063 LookupParsedName(R, S, &SS, !IvarLookupFollowUp); 1064 1065 // If this reference is in an Objective-C method, then we need to do 1066 // some special Objective-C lookup, too. 1067 if (IvarLookupFollowUp) { 1068 OwningExprResult E(LookupInObjCMethod(R, S, II, true)); 1069 if (E.isInvalid()) 1070 return ExprError(); 1071 1072 Expr *Ex = E.takeAs<Expr>(); 1073 if (Ex) return Owned(Ex); 1074 } 1075 } 1076 1077 if (R.isAmbiguous()) 1078 return ExprError(); 1079 1080 // Determine whether this name might be a candidate for 1081 // argument-dependent lookup. 1082 bool ADL = UseArgumentDependentLookup(SS, R, HasTrailingLParen); 1083 1084 if (R.empty() && !ADL) { 1085 // Otherwise, this could be an implicitly declared function reference (legal 1086 // in C90, extension in C99, forbidden in C++). 1087 if (HasTrailingLParen && II && !getLangOptions().CPlusPlus) { 1088 NamedDecl *D = ImplicitlyDefineFunction(NameLoc, *II, S); 1089 if (D) R.addDecl(D); 1090 } 1091 1092 // If this name wasn't predeclared and if this is not a function 1093 // call, diagnose the problem. 1094 if (R.empty()) { 1095 if (DiagnoseEmptyLookup(S, SS, R, CTC_Unknown)) 1096 return ExprError(); 1097 1098 assert(!R.empty() && 1099 "DiagnoseEmptyLookup returned false but added no results"); 1100 1101 // If we found an Objective-C instance variable, let 1102 // LookupInObjCMethod build the appropriate expression to 1103 // reference the ivar. 1104 if (ObjCIvarDecl *Ivar = R.getAsSingle<ObjCIvarDecl>()) { 1105 R.clear(); 1106 OwningExprResult E(LookupInObjCMethod(R, S, Ivar->getIdentifier())); 1107 assert(E.isInvalid() || E.get()); 1108 return move(E); 1109 } 1110 } 1111 } 1112 1113 // This is guaranteed from this point on. 1114 assert(!R.empty() || ADL); 1115 1116 if (VarDecl *Var = R.getAsSingle<VarDecl>()) { 1117 // Warn about constructs like: 1118 // if (void *X = foo()) { ... } else { X }. 1119 // In the else block, the pointer is always false. 1120 if (Var->isDeclaredInCondition() && Var->getType()->isScalarType()) { 1121 Scope *CheckS = S; 1122 while (CheckS && CheckS->getControlParent()) { 1123 if ((CheckS->getFlags() & Scope::ElseScope) && 1124 CheckS->getControlParent()->isDeclScope(DeclPtrTy::make(Var))) { 1125 ExprError(Diag(NameLoc, diag::warn_value_always_zero) 1126 << Var->getDeclName() 1127 << (Var->getType()->isPointerType() ? 2 : 1128 Var->getType()->isBooleanType() ? 1 : 0)); 1129 break; 1130 } 1131 1132 // Move to the parent of this scope. 1133 CheckS = CheckS->getParent(); 1134 } 1135 } 1136 } else if (FunctionDecl *Func = R.getAsSingle<FunctionDecl>()) { 1137 if (!getLangOptions().CPlusPlus && !Func->hasPrototype()) { 1138 // C99 DR 316 says that, if a function type comes from a 1139 // function definition (without a prototype), that type is only 1140 // used for checking compatibility. Therefore, when referencing 1141 // the function, we pretend that we don't have the full function 1142 // type. 1143 if (DiagnoseUseOfDecl(Func, NameLoc)) 1144 return ExprError(); 1145 1146 QualType T = Func->getType(); 1147 QualType NoProtoType = T; 1148 if (const FunctionProtoType *Proto = T->getAs<FunctionProtoType>()) 1149 NoProtoType = Context.getFunctionNoProtoType(Proto->getResultType(), 1150 Proto->getExtInfo()); 1151 return BuildDeclRefExpr(Func, NoProtoType, NameLoc, &SS); 1152 } 1153 } 1154 1155 // Check whether this might be a C++ implicit instance member access. 1156 // C++ [expr.prim.general]p6: 1157 // Within the definition of a non-static member function, an 1158 // identifier that names a non-static member is transformed to a 1159 // class member access expression. 1160 // But note that &SomeClass::foo is grammatically distinct, even 1161 // though we don't parse it that way. 1162 if (!R.empty() && (*R.begin())->isCXXClassMember()) { 1163 bool isAbstractMemberPointer = (isAddressOfOperand && !SS.isEmpty()); 1164 if (!isAbstractMemberPointer) 1165 return BuildPossibleImplicitMemberExpr(SS, R, TemplateArgs); 1166 } 1167 1168 if (TemplateArgs) 1169 return BuildTemplateIdExpr(SS, R, ADL, *TemplateArgs); 1170 1171 return BuildDeclarationNameExpr(SS, R, ADL); 1172} 1173 1174/// Builds an expression which might be an implicit member expression. 1175Sema::OwningExprResult 1176Sema::BuildPossibleImplicitMemberExpr(const CXXScopeSpec &SS, 1177 LookupResult &R, 1178 const TemplateArgumentListInfo *TemplateArgs) { 1179 switch (ClassifyImplicitMemberAccess(*this, R)) { 1180 case IMA_Instance: 1181 return BuildImplicitMemberExpr(SS, R, TemplateArgs, true); 1182 1183 case IMA_AnonymousMember: 1184 assert(R.isSingleResult()); 1185 return BuildAnonymousStructUnionMemberReference(R.getNameLoc(), 1186 R.getAsSingle<FieldDecl>()); 1187 1188 case IMA_Mixed: 1189 case IMA_Mixed_Unrelated: 1190 case IMA_Unresolved: 1191 return BuildImplicitMemberExpr(SS, R, TemplateArgs, false); 1192 1193 case IMA_Static: 1194 case IMA_Mixed_StaticContext: 1195 case IMA_Unresolved_StaticContext: 1196 if (TemplateArgs) 1197 return BuildTemplateIdExpr(SS, R, false, *TemplateArgs); 1198 return BuildDeclarationNameExpr(SS, R, false); 1199 1200 case IMA_Error_StaticContext: 1201 case IMA_Error_Unrelated: 1202 DiagnoseInstanceReference(*this, SS, R); 1203 return ExprError(); 1204 } 1205 1206 llvm_unreachable("unexpected instance member access kind"); 1207 return ExprError(); 1208} 1209 1210/// BuildQualifiedDeclarationNameExpr - Build a C++ qualified 1211/// declaration name, generally during template instantiation. 1212/// There's a large number of things which don't need to be done along 1213/// this path. 1214Sema::OwningExprResult 1215Sema::BuildQualifiedDeclarationNameExpr(CXXScopeSpec &SS, 1216 DeclarationName Name, 1217 SourceLocation NameLoc) { 1218 DeclContext *DC; 1219 if (!(DC = computeDeclContext(SS, false)) || DC->isDependentContext()) 1220 return BuildDependentDeclRefExpr(SS, Name, NameLoc, 0); 1221 1222 if (RequireCompleteDeclContext(SS, DC)) 1223 return ExprError(); 1224 1225 LookupResult R(*this, Name, NameLoc, LookupOrdinaryName); 1226 LookupQualifiedName(R, DC); 1227 1228 if (R.isAmbiguous()) 1229 return ExprError(); 1230 1231 if (R.empty()) { 1232 Diag(NameLoc, diag::err_no_member) << Name << DC << SS.getRange(); 1233 return ExprError(); 1234 } 1235 1236 return BuildDeclarationNameExpr(SS, R, /*ADL*/ false); 1237} 1238 1239/// LookupInObjCMethod - The parser has read a name in, and Sema has 1240/// detected that we're currently inside an ObjC method. Perform some 1241/// additional lookup. 1242/// 1243/// Ideally, most of this would be done by lookup, but there's 1244/// actually quite a lot of extra work involved. 1245/// 1246/// Returns a null sentinel to indicate trivial success. 1247Sema::OwningExprResult 1248Sema::LookupInObjCMethod(LookupResult &Lookup, Scope *S, 1249 IdentifierInfo *II, bool AllowBuiltinCreation) { 1250 SourceLocation Loc = Lookup.getNameLoc(); 1251 ObjCMethodDecl *CurMethod = getCurMethodDecl(); 1252 1253 // There are two cases to handle here. 1) scoped lookup could have failed, 1254 // in which case we should look for an ivar. 2) scoped lookup could have 1255 // found a decl, but that decl is outside the current instance method (i.e. 1256 // a global variable). In these two cases, we do a lookup for an ivar with 1257 // this name, if the lookup sucedes, we replace it our current decl. 1258 1259 // If we're in a class method, we don't normally want to look for 1260 // ivars. But if we don't find anything else, and there's an 1261 // ivar, that's an error. 1262 bool IsClassMethod = CurMethod->isClassMethod(); 1263 1264 bool LookForIvars; 1265 if (Lookup.empty()) 1266 LookForIvars = true; 1267 else if (IsClassMethod) 1268 LookForIvars = false; 1269 else 1270 LookForIvars = (Lookup.isSingleResult() && 1271 Lookup.getFoundDecl()->isDefinedOutsideFunctionOrMethod()); 1272 ObjCInterfaceDecl *IFace = 0; 1273 if (LookForIvars) { 1274 IFace = CurMethod->getClassInterface(); 1275 ObjCInterfaceDecl *ClassDeclared; 1276 if (ObjCIvarDecl *IV = IFace->lookupInstanceVariable(II, ClassDeclared)) { 1277 // Diagnose using an ivar in a class method. 1278 if (IsClassMethod) 1279 return ExprError(Diag(Loc, diag::error_ivar_use_in_class_method) 1280 << IV->getDeclName()); 1281 1282 // If we're referencing an invalid decl, just return this as a silent 1283 // error node. The error diagnostic was already emitted on the decl. 1284 if (IV->isInvalidDecl()) 1285 return ExprError(); 1286 1287 // Check if referencing a field with __attribute__((deprecated)). 1288 if (DiagnoseUseOfDecl(IV, Loc)) 1289 return ExprError(); 1290 1291 // Diagnose the use of an ivar outside of the declaring class. 1292 if (IV->getAccessControl() == ObjCIvarDecl::Private && 1293 ClassDeclared != IFace) 1294 Diag(Loc, diag::error_private_ivar_access) << IV->getDeclName(); 1295 1296 // FIXME: This should use a new expr for a direct reference, don't 1297 // turn this into Self->ivar, just return a BareIVarExpr or something. 1298 IdentifierInfo &II = Context.Idents.get("self"); 1299 UnqualifiedId SelfName; 1300 SelfName.setIdentifier(&II, SourceLocation()); 1301 CXXScopeSpec SelfScopeSpec; 1302 OwningExprResult SelfExpr = ActOnIdExpression(S, SelfScopeSpec, 1303 SelfName, false, false); 1304 MarkDeclarationReferenced(Loc, IV); 1305 return Owned(new (Context) 1306 ObjCIvarRefExpr(IV, IV->getType(), Loc, 1307 SelfExpr.takeAs<Expr>(), true, true)); 1308 } 1309 } else if (CurMethod->isInstanceMethod()) { 1310 // We should warn if a local variable hides an ivar. 1311 ObjCInterfaceDecl *IFace = CurMethod->getClassInterface(); 1312 ObjCInterfaceDecl *ClassDeclared; 1313 if (ObjCIvarDecl *IV = IFace->lookupInstanceVariable(II, ClassDeclared)) { 1314 if (IV->getAccessControl() != ObjCIvarDecl::Private || 1315 IFace == ClassDeclared) 1316 Diag(Loc, diag::warn_ivar_use_hidden) << IV->getDeclName(); 1317 } 1318 } 1319 1320 if (Lookup.empty() && II && AllowBuiltinCreation) { 1321 // FIXME. Consolidate this with similar code in LookupName. 1322 if (unsigned BuiltinID = II->getBuiltinID()) { 1323 if (!(getLangOptions().CPlusPlus && 1324 Context.BuiltinInfo.isPredefinedLibFunction(BuiltinID))) { 1325 NamedDecl *D = LazilyCreateBuiltin((IdentifierInfo *)II, BuiltinID, 1326 S, Lookup.isForRedeclaration(), 1327 Lookup.getNameLoc()); 1328 if (D) Lookup.addDecl(D); 1329 } 1330 } 1331 } 1332 // Sentinel value saying that we didn't do anything special. 1333 return Owned((Expr*) 0); 1334} 1335 1336/// \brief Cast a base object to a member's actual type. 1337/// 1338/// Logically this happens in three phases: 1339/// 1340/// * First we cast from the base type to the naming class. 1341/// The naming class is the class into which we were looking 1342/// when we found the member; it's the qualifier type if a 1343/// qualifier was provided, and otherwise it's the base type. 1344/// 1345/// * Next we cast from the naming class to the declaring class. 1346/// If the member we found was brought into a class's scope by 1347/// a using declaration, this is that class; otherwise it's 1348/// the class declaring the member. 1349/// 1350/// * Finally we cast from the declaring class to the "true" 1351/// declaring class of the member. This conversion does not 1352/// obey access control. 1353bool 1354Sema::PerformObjectMemberConversion(Expr *&From, 1355 NestedNameSpecifier *Qualifier, 1356 NamedDecl *FoundDecl, 1357 NamedDecl *Member) { 1358 CXXRecordDecl *RD = dyn_cast<CXXRecordDecl>(Member->getDeclContext()); 1359 if (!RD) 1360 return false; 1361 1362 QualType DestRecordType; 1363 QualType DestType; 1364 QualType FromRecordType; 1365 QualType FromType = From->getType(); 1366 bool PointerConversions = false; 1367 if (isa<FieldDecl>(Member)) { 1368 DestRecordType = Context.getCanonicalType(Context.getTypeDeclType(RD)); 1369 1370 if (FromType->getAs<PointerType>()) { 1371 DestType = Context.getPointerType(DestRecordType); 1372 FromRecordType = FromType->getPointeeType(); 1373 PointerConversions = true; 1374 } else { 1375 DestType = DestRecordType; 1376 FromRecordType = FromType; 1377 } 1378 } else if (CXXMethodDecl *Method = dyn_cast<CXXMethodDecl>(Member)) { 1379 if (Method->isStatic()) 1380 return false; 1381 1382 DestType = Method->getThisType(Context); 1383 DestRecordType = DestType->getPointeeType(); 1384 1385 if (FromType->getAs<PointerType>()) { 1386 FromRecordType = FromType->getPointeeType(); 1387 PointerConversions = true; 1388 } else { 1389 FromRecordType = FromType; 1390 DestType = DestRecordType; 1391 } 1392 } else { 1393 // No conversion necessary. 1394 return false; 1395 } 1396 1397 if (DestType->isDependentType() || FromType->isDependentType()) 1398 return false; 1399 1400 // If the unqualified types are the same, no conversion is necessary. 1401 if (Context.hasSameUnqualifiedType(FromRecordType, DestRecordType)) 1402 return false; 1403 1404 SourceRange FromRange = From->getSourceRange(); 1405 SourceLocation FromLoc = FromRange.getBegin(); 1406 1407 bool isLvalue 1408 = (From->isLvalue(Context) == Expr::LV_Valid) && !PointerConversions; 1409 1410 // C++ [class.member.lookup]p8: 1411 // [...] Ambiguities can often be resolved by qualifying a name with its 1412 // class name. 1413 // 1414 // If the member was a qualified name and the qualified referred to a 1415 // specific base subobject type, we'll cast to that intermediate type 1416 // first and then to the object in which the member is declared. That allows 1417 // one to resolve ambiguities in, e.g., a diamond-shaped hierarchy such as: 1418 // 1419 // class Base { public: int x; }; 1420 // class Derived1 : public Base { }; 1421 // class Derived2 : public Base { }; 1422 // class VeryDerived : public Derived1, public Derived2 { void f(); }; 1423 // 1424 // void VeryDerived::f() { 1425 // x = 17; // error: ambiguous base subobjects 1426 // Derived1::x = 17; // okay, pick the Base subobject of Derived1 1427 // } 1428 if (Qualifier) { 1429 QualType QType = QualType(Qualifier->getAsType(), 0); 1430 assert(!QType.isNull() && "lookup done with dependent qualifier?"); 1431 assert(QType->isRecordType() && "lookup done with non-record type"); 1432 1433 QualType QRecordType = QualType(QType->getAs<RecordType>(), 0); 1434 1435 // In C++98, the qualifier type doesn't actually have to be a base 1436 // type of the object type, in which case we just ignore it. 1437 // Otherwise build the appropriate casts. 1438 if (IsDerivedFrom(FromRecordType, QRecordType)) { 1439 CXXBaseSpecifierArray BasePath; 1440 if (CheckDerivedToBaseConversion(FromRecordType, QRecordType, 1441 FromLoc, FromRange, &BasePath)) 1442 return true; 1443 1444 if (PointerConversions) 1445 QType = Context.getPointerType(QType); 1446 ImpCastExprToType(From, QType, CastExpr::CK_UncheckedDerivedToBase, 1447 isLvalue, BasePath); 1448 1449 FromType = QType; 1450 FromRecordType = QRecordType; 1451 1452 // If the qualifier type was the same as the destination type, 1453 // we're done. 1454 if (Context.hasSameUnqualifiedType(FromRecordType, DestRecordType)) 1455 return false; 1456 } 1457 } 1458 1459 bool IgnoreAccess = false; 1460 1461 // If we actually found the member through a using declaration, cast 1462 // down to the using declaration's type. 1463 // 1464 // Pointer equality is fine here because only one declaration of a 1465 // class ever has member declarations. 1466 if (FoundDecl->getDeclContext() != Member->getDeclContext()) { 1467 assert(isa<UsingShadowDecl>(FoundDecl)); 1468 QualType URecordType = Context.getTypeDeclType( 1469 cast<CXXRecordDecl>(FoundDecl->getDeclContext())); 1470 1471 // We only need to do this if the naming-class to declaring-class 1472 // conversion is non-trivial. 1473 if (!Context.hasSameUnqualifiedType(FromRecordType, URecordType)) { 1474 assert(IsDerivedFrom(FromRecordType, URecordType)); 1475 CXXBaseSpecifierArray BasePath; 1476 if (CheckDerivedToBaseConversion(FromRecordType, URecordType, 1477 FromLoc, FromRange, &BasePath)) 1478 return true; 1479 1480 QualType UType = URecordType; 1481 if (PointerConversions) 1482 UType = Context.getPointerType(UType); 1483 ImpCastExprToType(From, UType, CastExpr::CK_UncheckedDerivedToBase, 1484 isLvalue, BasePath); 1485 FromType = UType; 1486 FromRecordType = URecordType; 1487 } 1488 1489 // We don't do access control for the conversion from the 1490 // declaring class to the true declaring class. 1491 IgnoreAccess = true; 1492 } 1493 1494 CXXBaseSpecifierArray BasePath; 1495 if (CheckDerivedToBaseConversion(FromRecordType, DestRecordType, 1496 FromLoc, FromRange, &BasePath, 1497 IgnoreAccess)) 1498 return true; 1499 1500 ImpCastExprToType(From, DestType, CastExpr::CK_UncheckedDerivedToBase, 1501 isLvalue, BasePath); 1502 return false; 1503} 1504 1505/// \brief Build a MemberExpr AST node. 1506static MemberExpr *BuildMemberExpr(ASTContext &C, Expr *Base, bool isArrow, 1507 const CXXScopeSpec &SS, ValueDecl *Member, 1508 DeclAccessPair FoundDecl, 1509 SourceLocation Loc, QualType Ty, 1510 const TemplateArgumentListInfo *TemplateArgs = 0) { 1511 NestedNameSpecifier *Qualifier = 0; 1512 SourceRange QualifierRange; 1513 if (SS.isSet()) { 1514 Qualifier = (NestedNameSpecifier *) SS.getScopeRep(); 1515 QualifierRange = SS.getRange(); 1516 } 1517 1518 return MemberExpr::Create(C, Base, isArrow, Qualifier, QualifierRange, 1519 Member, FoundDecl, Loc, TemplateArgs, Ty); 1520} 1521 1522/// Builds an implicit member access expression. The current context 1523/// is known to be an instance method, and the given unqualified lookup 1524/// set is known to contain only instance members, at least one of which 1525/// is from an appropriate type. 1526Sema::OwningExprResult 1527Sema::BuildImplicitMemberExpr(const CXXScopeSpec &SS, 1528 LookupResult &R, 1529 const TemplateArgumentListInfo *TemplateArgs, 1530 bool IsKnownInstance) { 1531 assert(!R.empty() && !R.isAmbiguous()); 1532 1533 SourceLocation Loc = R.getNameLoc(); 1534 1535 // We may have found a field within an anonymous union or struct 1536 // (C++ [class.union]). 1537 // FIXME: This needs to happen post-isImplicitMemberReference? 1538 // FIXME: template-ids inside anonymous structs? 1539 if (FieldDecl *FD = R.getAsSingle<FieldDecl>()) 1540 if (cast<RecordDecl>(FD->getDeclContext())->isAnonymousStructOrUnion()) 1541 return BuildAnonymousStructUnionMemberReference(Loc, FD); 1542 1543 // If this is known to be an instance access, go ahead and build a 1544 // 'this' expression now. 1545 DeclContext *DC = getFunctionLevelDeclContext(); 1546 QualType ThisType = cast<CXXMethodDecl>(DC)->getThisType(Context); 1547 Expr *This = 0; // null signifies implicit access 1548 if (IsKnownInstance) { 1549 SourceLocation Loc = R.getNameLoc(); 1550 if (SS.getRange().isValid()) 1551 Loc = SS.getRange().getBegin(); 1552 This = new (Context) CXXThisExpr(Loc, ThisType, /*isImplicit=*/true); 1553 } 1554 1555 return BuildMemberReferenceExpr(ExprArg(*this, This), ThisType, 1556 /*OpLoc*/ SourceLocation(), 1557 /*IsArrow*/ true, 1558 SS, 1559 /*FirstQualifierInScope*/ 0, 1560 R, TemplateArgs); 1561} 1562 1563bool Sema::UseArgumentDependentLookup(const CXXScopeSpec &SS, 1564 const LookupResult &R, 1565 bool HasTrailingLParen) { 1566 // Only when used directly as the postfix-expression of a call. 1567 if (!HasTrailingLParen) 1568 return false; 1569 1570 // Never if a scope specifier was provided. 1571 if (SS.isSet()) 1572 return false; 1573 1574 // Only in C++ or ObjC++. 1575 if (!getLangOptions().CPlusPlus) 1576 return false; 1577 1578 // Turn off ADL when we find certain kinds of declarations during 1579 // normal lookup: 1580 for (LookupResult::iterator I = R.begin(), E = R.end(); I != E; ++I) { 1581 NamedDecl *D = *I; 1582 1583 // C++0x [basic.lookup.argdep]p3: 1584 // -- a declaration of a class member 1585 // Since using decls preserve this property, we check this on the 1586 // original decl. 1587 if (D->isCXXClassMember()) 1588 return false; 1589 1590 // C++0x [basic.lookup.argdep]p3: 1591 // -- a block-scope function declaration that is not a 1592 // using-declaration 1593 // NOTE: we also trigger this for function templates (in fact, we 1594 // don't check the decl type at all, since all other decl types 1595 // turn off ADL anyway). 1596 if (isa<UsingShadowDecl>(D)) 1597 D = cast<UsingShadowDecl>(D)->getTargetDecl(); 1598 else if (D->getDeclContext()->isFunctionOrMethod()) 1599 return false; 1600 1601 // C++0x [basic.lookup.argdep]p3: 1602 // -- a declaration that is neither a function or a function 1603 // template 1604 // And also for builtin functions. 1605 if (isa<FunctionDecl>(D)) { 1606 FunctionDecl *FDecl = cast<FunctionDecl>(D); 1607 1608 // But also builtin functions. 1609 if (FDecl->getBuiltinID() && FDecl->isImplicit()) 1610 return false; 1611 } else if (!isa<FunctionTemplateDecl>(D)) 1612 return false; 1613 } 1614 1615 return true; 1616} 1617 1618 1619/// Diagnoses obvious problems with the use of the given declaration 1620/// as an expression. This is only actually called for lookups that 1621/// were not overloaded, and it doesn't promise that the declaration 1622/// will in fact be used. 1623static bool CheckDeclInExpr(Sema &S, SourceLocation Loc, NamedDecl *D) { 1624 if (isa<TypedefDecl>(D)) { 1625 S.Diag(Loc, diag::err_unexpected_typedef) << D->getDeclName(); 1626 return true; 1627 } 1628 1629 if (isa<ObjCInterfaceDecl>(D)) { 1630 S.Diag(Loc, diag::err_unexpected_interface) << D->getDeclName(); 1631 return true; 1632 } 1633 1634 if (isa<NamespaceDecl>(D)) { 1635 S.Diag(Loc, diag::err_unexpected_namespace) << D->getDeclName(); 1636 return true; 1637 } 1638 1639 return false; 1640} 1641 1642Sema::OwningExprResult 1643Sema::BuildDeclarationNameExpr(const CXXScopeSpec &SS, 1644 LookupResult &R, 1645 bool NeedsADL) { 1646 // If this is a single, fully-resolved result and we don't need ADL, 1647 // just build an ordinary singleton decl ref. 1648 if (!NeedsADL && R.isSingleResult() && !R.getAsSingle<FunctionTemplateDecl>()) 1649 return BuildDeclarationNameExpr(SS, R.getNameLoc(), R.getFoundDecl()); 1650 1651 // We only need to check the declaration if there's exactly one 1652 // result, because in the overloaded case the results can only be 1653 // functions and function templates. 1654 if (R.isSingleResult() && 1655 CheckDeclInExpr(*this, R.getNameLoc(), R.getFoundDecl())) 1656 return ExprError(); 1657 1658 // Otherwise, just build an unresolved lookup expression. Suppress 1659 // any lookup-related diagnostics; we'll hash these out later, when 1660 // we've picked a target. 1661 R.suppressDiagnostics(); 1662 1663 bool Dependent 1664 = UnresolvedLookupExpr::ComputeDependence(R.begin(), R.end(), 0); 1665 UnresolvedLookupExpr *ULE 1666 = UnresolvedLookupExpr::Create(Context, Dependent, R.getNamingClass(), 1667 (NestedNameSpecifier*) SS.getScopeRep(), 1668 SS.getRange(), 1669 R.getLookupName(), R.getNameLoc(), 1670 NeedsADL, R.isOverloadedResult(), 1671 R.begin(), R.end()); 1672 1673 return Owned(ULE); 1674} 1675 1676 1677/// \brief Complete semantic analysis for a reference to the given declaration. 1678Sema::OwningExprResult 1679Sema::BuildDeclarationNameExpr(const CXXScopeSpec &SS, 1680 SourceLocation Loc, NamedDecl *D) { 1681 assert(D && "Cannot refer to a NULL declaration"); 1682 assert(!isa<FunctionTemplateDecl>(D) && 1683 "Cannot refer unambiguously to a function template"); 1684 1685 if (CheckDeclInExpr(*this, Loc, D)) 1686 return ExprError(); 1687 1688 if (TemplateDecl *Template = dyn_cast<TemplateDecl>(D)) { 1689 // Specifically diagnose references to class templates that are missing 1690 // a template argument list. 1691 Diag(Loc, diag::err_template_decl_ref) 1692 << Template << SS.getRange(); 1693 Diag(Template->getLocation(), diag::note_template_decl_here); 1694 return ExprError(); 1695 } 1696 1697 // Make sure that we're referring to a value. 1698 ValueDecl *VD = dyn_cast<ValueDecl>(D); 1699 if (!VD) { 1700 Diag(Loc, diag::err_ref_non_value) 1701 << D << SS.getRange(); 1702 Diag(D->getLocation(), diag::note_declared_at); 1703 return ExprError(); 1704 } 1705 1706 // Check whether this declaration can be used. Note that we suppress 1707 // this check when we're going to perform argument-dependent lookup 1708 // on this function name, because this might not be the function 1709 // that overload resolution actually selects. 1710 if (DiagnoseUseOfDecl(VD, Loc)) 1711 return ExprError(); 1712 1713 // Only create DeclRefExpr's for valid Decl's. 1714 if (VD->isInvalidDecl()) 1715 return ExprError(); 1716 1717 // If the identifier reference is inside a block, and it refers to a value 1718 // that is outside the block, create a BlockDeclRefExpr instead of a 1719 // DeclRefExpr. This ensures the value is treated as a copy-in snapshot when 1720 // the block is formed. 1721 // 1722 // We do not do this for things like enum constants, global variables, etc, 1723 // as they do not get snapshotted. 1724 // 1725 if (getCurBlock() && 1726 ShouldSnapshotBlockValueReference(*this, getCurBlock(), VD)) { 1727 if (VD->getType().getTypePtr()->isVariablyModifiedType()) { 1728 Diag(Loc, diag::err_ref_vm_type); 1729 Diag(D->getLocation(), diag::note_declared_at); 1730 return ExprError(); 1731 } 1732 1733 if (VD->getType()->isArrayType()) { 1734 Diag(Loc, diag::err_ref_array_type); 1735 Diag(D->getLocation(), diag::note_declared_at); 1736 return ExprError(); 1737 } 1738 1739 MarkDeclarationReferenced(Loc, VD); 1740 QualType ExprTy = VD->getType().getNonReferenceType(); 1741 // The BlocksAttr indicates the variable is bound by-reference. 1742 if (VD->getAttr<BlocksAttr>()) 1743 return Owned(new (Context) BlockDeclRefExpr(VD, ExprTy, Loc, true)); 1744 // This is to record that a 'const' was actually synthesize and added. 1745 bool constAdded = !ExprTy.isConstQualified(); 1746 // Variable will be bound by-copy, make it const within the closure. 1747 1748 ExprTy.addConst(); 1749 return Owned(new (Context) BlockDeclRefExpr(VD, ExprTy, Loc, false, 1750 constAdded)); 1751 } 1752 // If this reference is not in a block or if the referenced variable is 1753 // within the block, create a normal DeclRefExpr. 1754 1755 return BuildDeclRefExpr(VD, VD->getType().getNonReferenceType(), Loc, &SS); 1756} 1757 1758Sema::OwningExprResult Sema::ActOnPredefinedExpr(SourceLocation Loc, 1759 tok::TokenKind Kind) { 1760 PredefinedExpr::IdentType IT; 1761 1762 switch (Kind) { 1763 default: assert(0 && "Unknown simple primary expr!"); 1764 case tok::kw___func__: IT = PredefinedExpr::Func; break; // [C99 6.4.2.2] 1765 case tok::kw___FUNCTION__: IT = PredefinedExpr::Function; break; 1766 case tok::kw___PRETTY_FUNCTION__: IT = PredefinedExpr::PrettyFunction; break; 1767 } 1768 1769 // Pre-defined identifiers are of type char[x], where x is the length of the 1770 // string. 1771 1772 Decl *currentDecl = getCurFunctionOrMethodDecl(); 1773 if (!currentDecl) { 1774 Diag(Loc, diag::ext_predef_outside_function); 1775 currentDecl = Context.getTranslationUnitDecl(); 1776 } 1777 1778 QualType ResTy; 1779 if (cast<DeclContext>(currentDecl)->isDependentContext()) { 1780 ResTy = Context.DependentTy; 1781 } else { 1782 unsigned Length = PredefinedExpr::ComputeName(IT, currentDecl).length(); 1783 1784 llvm::APInt LengthI(32, Length + 1); 1785 ResTy = Context.CharTy.withConst(); 1786 ResTy = Context.getConstantArrayType(ResTy, LengthI, ArrayType::Normal, 0); 1787 } 1788 return Owned(new (Context) PredefinedExpr(Loc, ResTy, IT)); 1789} 1790 1791Sema::OwningExprResult Sema::ActOnCharacterConstant(const Token &Tok) { 1792 llvm::SmallString<16> CharBuffer; 1793 bool Invalid = false; 1794 llvm::StringRef ThisTok = PP.getSpelling(Tok, CharBuffer, &Invalid); 1795 if (Invalid) 1796 return ExprError(); 1797 1798 CharLiteralParser Literal(ThisTok.begin(), ThisTok.end(), Tok.getLocation(), 1799 PP); 1800 if (Literal.hadError()) 1801 return ExprError(); 1802 1803 QualType Ty; 1804 if (!getLangOptions().CPlusPlus) 1805 Ty = Context.IntTy; // 'x' and L'x' -> int in C. 1806 else if (Literal.isWide()) 1807 Ty = Context.WCharTy; // L'x' -> wchar_t in C++. 1808 else if (Literal.isMultiChar()) 1809 Ty = Context.IntTy; // 'wxyz' -> int in C++. 1810 else 1811 Ty = Context.CharTy; // 'x' -> char in C++ 1812 1813 return Owned(new (Context) CharacterLiteral(Literal.getValue(), 1814 Literal.isWide(), 1815 Ty, Tok.getLocation())); 1816} 1817 1818Action::OwningExprResult Sema::ActOnNumericConstant(const Token &Tok) { 1819 // Fast path for a single digit (which is quite common). A single digit 1820 // cannot have a trigraph, escaped newline, radix prefix, or type suffix. 1821 if (Tok.getLength() == 1) { 1822 const char Val = PP.getSpellingOfSingleCharacterNumericConstant(Tok); 1823 unsigned IntSize = Context.Target.getIntWidth(); 1824 return Owned(new (Context) IntegerLiteral(llvm::APInt(IntSize, Val-'0'), 1825 Context.IntTy, Tok.getLocation())); 1826 } 1827 1828 llvm::SmallString<512> IntegerBuffer; 1829 // Add padding so that NumericLiteralParser can overread by one character. 1830 IntegerBuffer.resize(Tok.getLength()+1); 1831 const char *ThisTokBegin = &IntegerBuffer[0]; 1832 1833 // Get the spelling of the token, which eliminates trigraphs, etc. 1834 bool Invalid = false; 1835 unsigned ActualLength = PP.getSpelling(Tok, ThisTokBegin, &Invalid); 1836 if (Invalid) 1837 return ExprError(); 1838 1839 NumericLiteralParser Literal(ThisTokBegin, ThisTokBegin+ActualLength, 1840 Tok.getLocation(), PP); 1841 if (Literal.hadError) 1842 return ExprError(); 1843 1844 Expr *Res; 1845 1846 if (Literal.isFloatingLiteral()) { 1847 QualType Ty; 1848 if (Literal.isFloat) 1849 Ty = Context.FloatTy; 1850 else if (!Literal.isLong) 1851 Ty = Context.DoubleTy; 1852 else 1853 Ty = Context.LongDoubleTy; 1854 1855 const llvm::fltSemantics &Format = Context.getFloatTypeSemantics(Ty); 1856 1857 using llvm::APFloat; 1858 APFloat Val(Format); 1859 1860 APFloat::opStatus result = Literal.GetFloatValue(Val); 1861 1862 // Overflow is always an error, but underflow is only an error if 1863 // we underflowed to zero (APFloat reports denormals as underflow). 1864 if ((result & APFloat::opOverflow) || 1865 ((result & APFloat::opUnderflow) && Val.isZero())) { 1866 unsigned diagnostic; 1867 llvm::SmallString<20> buffer; 1868 if (result & APFloat::opOverflow) { 1869 diagnostic = diag::warn_float_overflow; 1870 APFloat::getLargest(Format).toString(buffer); 1871 } else { 1872 diagnostic = diag::warn_float_underflow; 1873 APFloat::getSmallest(Format).toString(buffer); 1874 } 1875 1876 Diag(Tok.getLocation(), diagnostic) 1877 << Ty 1878 << llvm::StringRef(buffer.data(), buffer.size()); 1879 } 1880 1881 bool isExact = (result == APFloat::opOK); 1882 Res = new (Context) FloatingLiteral(Val, isExact, Ty, Tok.getLocation()); 1883 1884 } else if (!Literal.isIntegerLiteral()) { 1885 return ExprError(); 1886 } else { 1887 QualType Ty; 1888 1889 // long long is a C99 feature. 1890 if (!getLangOptions().C99 && !getLangOptions().CPlusPlus0x && 1891 Literal.isLongLong) 1892 Diag(Tok.getLocation(), diag::ext_longlong); 1893 1894 // Get the value in the widest-possible width. 1895 llvm::APInt ResultVal(Context.Target.getIntMaxTWidth(), 0); 1896 1897 if (Literal.GetIntegerValue(ResultVal)) { 1898 // If this value didn't fit into uintmax_t, warn and force to ull. 1899 Diag(Tok.getLocation(), diag::warn_integer_too_large); 1900 Ty = Context.UnsignedLongLongTy; 1901 assert(Context.getTypeSize(Ty) == ResultVal.getBitWidth() && 1902 "long long is not intmax_t?"); 1903 } else { 1904 // If this value fits into a ULL, try to figure out what else it fits into 1905 // according to the rules of C99 6.4.4.1p5. 1906 1907 // Octal, Hexadecimal, and integers with a U suffix are allowed to 1908 // be an unsigned int. 1909 bool AllowUnsigned = Literal.isUnsigned || Literal.getRadix() != 10; 1910 1911 // Check from smallest to largest, picking the smallest type we can. 1912 unsigned Width = 0; 1913 if (!Literal.isLong && !Literal.isLongLong) { 1914 // Are int/unsigned possibilities? 1915 unsigned IntSize = Context.Target.getIntWidth(); 1916 1917 // Does it fit in a unsigned int? 1918 if (ResultVal.isIntN(IntSize)) { 1919 // Does it fit in a signed int? 1920 if (!Literal.isUnsigned && ResultVal[IntSize-1] == 0) 1921 Ty = Context.IntTy; 1922 else if (AllowUnsigned) 1923 Ty = Context.UnsignedIntTy; 1924 Width = IntSize; 1925 } 1926 } 1927 1928 // Are long/unsigned long possibilities? 1929 if (Ty.isNull() && !Literal.isLongLong) { 1930 unsigned LongSize = Context.Target.getLongWidth(); 1931 1932 // Does it fit in a unsigned long? 1933 if (ResultVal.isIntN(LongSize)) { 1934 // Does it fit in a signed long? 1935 if (!Literal.isUnsigned && ResultVal[LongSize-1] == 0) 1936 Ty = Context.LongTy; 1937 else if (AllowUnsigned) 1938 Ty = Context.UnsignedLongTy; 1939 Width = LongSize; 1940 } 1941 } 1942 1943 // Finally, check long long if needed. 1944 if (Ty.isNull()) { 1945 unsigned LongLongSize = Context.Target.getLongLongWidth(); 1946 1947 // Does it fit in a unsigned long long? 1948 if (ResultVal.isIntN(LongLongSize)) { 1949 // Does it fit in a signed long long? 1950 if (!Literal.isUnsigned && ResultVal[LongLongSize-1] == 0) 1951 Ty = Context.LongLongTy; 1952 else if (AllowUnsigned) 1953 Ty = Context.UnsignedLongLongTy; 1954 Width = LongLongSize; 1955 } 1956 } 1957 1958 // If we still couldn't decide a type, we probably have something that 1959 // does not fit in a signed long long, but has no U suffix. 1960 if (Ty.isNull()) { 1961 Diag(Tok.getLocation(), diag::warn_integer_too_large_for_signed); 1962 Ty = Context.UnsignedLongLongTy; 1963 Width = Context.Target.getLongLongWidth(); 1964 } 1965 1966 if (ResultVal.getBitWidth() != Width) 1967 ResultVal.trunc(Width); 1968 } 1969 Res = new (Context) IntegerLiteral(ResultVal, Ty, Tok.getLocation()); 1970 } 1971 1972 // If this is an imaginary literal, create the ImaginaryLiteral wrapper. 1973 if (Literal.isImaginary) 1974 Res = new (Context) ImaginaryLiteral(Res, 1975 Context.getComplexType(Res->getType())); 1976 1977 return Owned(Res); 1978} 1979 1980Action::OwningExprResult Sema::ActOnParenExpr(SourceLocation L, 1981 SourceLocation R, ExprArg Val) { 1982 Expr *E = Val.takeAs<Expr>(); 1983 assert((E != 0) && "ActOnParenExpr() missing expr"); 1984 return Owned(new (Context) ParenExpr(L, R, E)); 1985} 1986 1987/// The UsualUnaryConversions() function is *not* called by this routine. 1988/// See C99 6.3.2.1p[2-4] for more details. 1989bool Sema::CheckSizeOfAlignOfOperand(QualType exprType, 1990 SourceLocation OpLoc, 1991 const SourceRange &ExprRange, 1992 bool isSizeof) { 1993 if (exprType->isDependentType()) 1994 return false; 1995 1996 // C++ [expr.sizeof]p2: "When applied to a reference or a reference type, 1997 // the result is the size of the referenced type." 1998 // C++ [expr.alignof]p3: "When alignof is applied to a reference type, the 1999 // result shall be the alignment of the referenced type." 2000 if (const ReferenceType *Ref = exprType->getAs<ReferenceType>()) 2001 exprType = Ref->getPointeeType(); 2002 2003 // C99 6.5.3.4p1: 2004 if (exprType->isFunctionType()) { 2005 // alignof(function) is allowed as an extension. 2006 if (isSizeof) 2007 Diag(OpLoc, diag::ext_sizeof_function_type) << ExprRange; 2008 return false; 2009 } 2010 2011 // Allow sizeof(void)/alignof(void) as an extension. 2012 if (exprType->isVoidType()) { 2013 Diag(OpLoc, diag::ext_sizeof_void_type) 2014 << (isSizeof ? "sizeof" : "__alignof") << ExprRange; 2015 return false; 2016 } 2017 2018 if (RequireCompleteType(OpLoc, exprType, 2019 PDiag(diag::err_sizeof_alignof_incomplete_type) 2020 << int(!isSizeof) << ExprRange)) 2021 return true; 2022 2023 // Reject sizeof(interface) and sizeof(interface<proto>) in 64-bit mode. 2024 if (LangOpts.ObjCNonFragileABI && exprType->isObjCObjectType()) { 2025 Diag(OpLoc, diag::err_sizeof_nonfragile_interface) 2026 << exprType << isSizeof << ExprRange; 2027 return true; 2028 } 2029 2030 return false; 2031} 2032 2033bool Sema::CheckAlignOfExpr(Expr *E, SourceLocation OpLoc, 2034 const SourceRange &ExprRange) { 2035 E = E->IgnoreParens(); 2036 2037 // alignof decl is always ok. 2038 if (isa<DeclRefExpr>(E)) 2039 return false; 2040 2041 // Cannot know anything else if the expression is dependent. 2042 if (E->isTypeDependent()) 2043 return false; 2044 2045 if (E->getBitField()) { 2046 Diag(OpLoc, diag::err_sizeof_alignof_bitfield) << 1 << ExprRange; 2047 return true; 2048 } 2049 2050 // Alignment of a field access is always okay, so long as it isn't a 2051 // bit-field. 2052 if (MemberExpr *ME = dyn_cast<MemberExpr>(E)) 2053 if (isa<FieldDecl>(ME->getMemberDecl())) 2054 return false; 2055 2056 return CheckSizeOfAlignOfOperand(E->getType(), OpLoc, ExprRange, false); 2057} 2058 2059/// \brief Build a sizeof or alignof expression given a type operand. 2060Action::OwningExprResult 2061Sema::CreateSizeOfAlignOfExpr(TypeSourceInfo *TInfo, 2062 SourceLocation OpLoc, 2063 bool isSizeOf, SourceRange R) { 2064 if (!TInfo) 2065 return ExprError(); 2066 2067 QualType T = TInfo->getType(); 2068 2069 if (!T->isDependentType() && 2070 CheckSizeOfAlignOfOperand(T, OpLoc, R, isSizeOf)) 2071 return ExprError(); 2072 2073 // C99 6.5.3.4p4: the type (an unsigned integer type) is size_t. 2074 return Owned(new (Context) SizeOfAlignOfExpr(isSizeOf, TInfo, 2075 Context.getSizeType(), OpLoc, 2076 R.getEnd())); 2077} 2078 2079/// \brief Build a sizeof or alignof expression given an expression 2080/// operand. 2081Action::OwningExprResult 2082Sema::CreateSizeOfAlignOfExpr(Expr *E, SourceLocation OpLoc, 2083 bool isSizeOf, SourceRange R) { 2084 // Verify that the operand is valid. 2085 bool isInvalid = false; 2086 if (E->isTypeDependent()) { 2087 // Delay type-checking for type-dependent expressions. 2088 } else if (!isSizeOf) { 2089 isInvalid = CheckAlignOfExpr(E, OpLoc, R); 2090 } else if (E->getBitField()) { // C99 6.5.3.4p1. 2091 Diag(OpLoc, diag::err_sizeof_alignof_bitfield) << 0; 2092 isInvalid = true; 2093 } else { 2094 isInvalid = CheckSizeOfAlignOfOperand(E->getType(), OpLoc, R, true); 2095 } 2096 2097 if (isInvalid) 2098 return ExprError(); 2099 2100 // C99 6.5.3.4p4: the type (an unsigned integer type) is size_t. 2101 return Owned(new (Context) SizeOfAlignOfExpr(isSizeOf, E, 2102 Context.getSizeType(), OpLoc, 2103 R.getEnd())); 2104} 2105 2106/// ActOnSizeOfAlignOfExpr - Handle @c sizeof(type) and @c sizeof @c expr and 2107/// the same for @c alignof and @c __alignof 2108/// Note that the ArgRange is invalid if isType is false. 2109Action::OwningExprResult 2110Sema::ActOnSizeOfAlignOfExpr(SourceLocation OpLoc, bool isSizeof, bool isType, 2111 void *TyOrEx, const SourceRange &ArgRange) { 2112 // If error parsing type, ignore. 2113 if (TyOrEx == 0) return ExprError(); 2114 2115 if (isType) { 2116 TypeSourceInfo *TInfo; 2117 (void) GetTypeFromParser(TyOrEx, &TInfo); 2118 return CreateSizeOfAlignOfExpr(TInfo, OpLoc, isSizeof, ArgRange); 2119 } 2120 2121 Expr *ArgEx = (Expr *)TyOrEx; 2122 Action::OwningExprResult Result 2123 = CreateSizeOfAlignOfExpr(ArgEx, OpLoc, isSizeof, ArgEx->getSourceRange()); 2124 2125 if (Result.isInvalid()) 2126 DeleteExpr(ArgEx); 2127 2128 return move(Result); 2129} 2130 2131QualType Sema::CheckRealImagOperand(Expr *&V, SourceLocation Loc, bool isReal) { 2132 if (V->isTypeDependent()) 2133 return Context.DependentTy; 2134 2135 // These operators return the element type of a complex type. 2136 if (const ComplexType *CT = V->getType()->getAs<ComplexType>()) 2137 return CT->getElementType(); 2138 2139 // Otherwise they pass through real integer and floating point types here. 2140 if (V->getType()->isArithmeticType()) 2141 return V->getType(); 2142 2143 // Reject anything else. 2144 Diag(Loc, diag::err_realimag_invalid_type) << V->getType() 2145 << (isReal ? "__real" : "__imag"); 2146 return QualType(); 2147} 2148 2149 2150 2151Action::OwningExprResult 2152Sema::ActOnPostfixUnaryOp(Scope *S, SourceLocation OpLoc, 2153 tok::TokenKind Kind, ExprArg Input) { 2154 UnaryOperator::Opcode Opc; 2155 switch (Kind) { 2156 default: assert(0 && "Unknown unary op!"); 2157 case tok::plusplus: Opc = UnaryOperator::PostInc; break; 2158 case tok::minusminus: Opc = UnaryOperator::PostDec; break; 2159 } 2160 2161 return BuildUnaryOp(S, OpLoc, Opc, move(Input)); 2162} 2163 2164Action::OwningExprResult 2165Sema::ActOnArraySubscriptExpr(Scope *S, ExprArg Base, SourceLocation LLoc, 2166 ExprArg Idx, SourceLocation RLoc) { 2167 // Since this might be a postfix expression, get rid of ParenListExprs. 2168 Base = MaybeConvertParenListExprToParenExpr(S, move(Base)); 2169 2170 Expr *LHSExp = static_cast<Expr*>(Base.get()), 2171 *RHSExp = static_cast<Expr*>(Idx.get()); 2172 2173 if (getLangOptions().CPlusPlus && 2174 (LHSExp->isTypeDependent() || RHSExp->isTypeDependent())) { 2175 Base.release(); 2176 Idx.release(); 2177 return Owned(new (Context) ArraySubscriptExpr(LHSExp, RHSExp, 2178 Context.DependentTy, RLoc)); 2179 } 2180 2181 if (getLangOptions().CPlusPlus && 2182 (LHSExp->getType()->isRecordType() || 2183 LHSExp->getType()->isEnumeralType() || 2184 RHSExp->getType()->isRecordType() || 2185 RHSExp->getType()->isEnumeralType())) { 2186 return CreateOverloadedArraySubscriptExpr(LLoc, RLoc, move(Base),move(Idx)); 2187 } 2188 2189 return CreateBuiltinArraySubscriptExpr(move(Base), LLoc, move(Idx), RLoc); 2190} 2191 2192 2193Action::OwningExprResult 2194Sema::CreateBuiltinArraySubscriptExpr(ExprArg Base, SourceLocation LLoc, 2195 ExprArg Idx, SourceLocation RLoc) { 2196 Expr *LHSExp = static_cast<Expr*>(Base.get()); 2197 Expr *RHSExp = static_cast<Expr*>(Idx.get()); 2198 2199 // Perform default conversions. 2200 if (!LHSExp->getType()->getAs<VectorType>()) 2201 DefaultFunctionArrayLvalueConversion(LHSExp); 2202 DefaultFunctionArrayLvalueConversion(RHSExp); 2203 2204 QualType LHSTy = LHSExp->getType(), RHSTy = RHSExp->getType(); 2205 2206 // C99 6.5.2.1p2: the expression e1[e2] is by definition precisely equivalent 2207 // to the expression *((e1)+(e2)). This means the array "Base" may actually be 2208 // in the subscript position. As a result, we need to derive the array base 2209 // and index from the expression types. 2210 Expr *BaseExpr, *IndexExpr; 2211 QualType ResultType; 2212 if (LHSTy->isDependentType() || RHSTy->isDependentType()) { 2213 BaseExpr = LHSExp; 2214 IndexExpr = RHSExp; 2215 ResultType = Context.DependentTy; 2216 } else if (const PointerType *PTy = LHSTy->getAs<PointerType>()) { 2217 BaseExpr = LHSExp; 2218 IndexExpr = RHSExp; 2219 ResultType = PTy->getPointeeType(); 2220 } else if (const PointerType *PTy = RHSTy->getAs<PointerType>()) { 2221 // Handle the uncommon case of "123[Ptr]". 2222 BaseExpr = RHSExp; 2223 IndexExpr = LHSExp; 2224 ResultType = PTy->getPointeeType(); 2225 } else if (const ObjCObjectPointerType *PTy = 2226 LHSTy->getAs<ObjCObjectPointerType>()) { 2227 BaseExpr = LHSExp; 2228 IndexExpr = RHSExp; 2229 ResultType = PTy->getPointeeType(); 2230 } else if (const ObjCObjectPointerType *PTy = 2231 RHSTy->getAs<ObjCObjectPointerType>()) { 2232 // Handle the uncommon case of "123[Ptr]". 2233 BaseExpr = RHSExp; 2234 IndexExpr = LHSExp; 2235 ResultType = PTy->getPointeeType(); 2236 } else if (const VectorType *VTy = LHSTy->getAs<VectorType>()) { 2237 BaseExpr = LHSExp; // vectors: V[123] 2238 IndexExpr = RHSExp; 2239 2240 // FIXME: need to deal with const... 2241 ResultType = VTy->getElementType(); 2242 } else if (LHSTy->isArrayType()) { 2243 // If we see an array that wasn't promoted by 2244 // DefaultFunctionArrayLvalueConversion, it must be an array that 2245 // wasn't promoted because of the C90 rule that doesn't 2246 // allow promoting non-lvalue arrays. Warn, then 2247 // force the promotion here. 2248 Diag(LHSExp->getLocStart(), diag::ext_subscript_non_lvalue) << 2249 LHSExp->getSourceRange(); 2250 ImpCastExprToType(LHSExp, Context.getArrayDecayedType(LHSTy), 2251 CastExpr::CK_ArrayToPointerDecay); 2252 LHSTy = LHSExp->getType(); 2253 2254 BaseExpr = LHSExp; 2255 IndexExpr = RHSExp; 2256 ResultType = LHSTy->getAs<PointerType>()->getPointeeType(); 2257 } else if (RHSTy->isArrayType()) { 2258 // Same as previous, except for 123[f().a] case 2259 Diag(RHSExp->getLocStart(), diag::ext_subscript_non_lvalue) << 2260 RHSExp->getSourceRange(); 2261 ImpCastExprToType(RHSExp, Context.getArrayDecayedType(RHSTy), 2262 CastExpr::CK_ArrayToPointerDecay); 2263 RHSTy = RHSExp->getType(); 2264 2265 BaseExpr = RHSExp; 2266 IndexExpr = LHSExp; 2267 ResultType = RHSTy->getAs<PointerType>()->getPointeeType(); 2268 } else { 2269 return ExprError(Diag(LLoc, diag::err_typecheck_subscript_value) 2270 << LHSExp->getSourceRange() << RHSExp->getSourceRange()); 2271 } 2272 // C99 6.5.2.1p1 2273 if (!(IndexExpr->getType()->isIntegerType() && 2274 IndexExpr->getType()->isScalarType()) && !IndexExpr->isTypeDependent()) 2275 return ExprError(Diag(LLoc, diag::err_typecheck_subscript_not_integer) 2276 << IndexExpr->getSourceRange()); 2277 2278 if ((IndexExpr->getType()->isSpecificBuiltinType(BuiltinType::Char_S) || 2279 IndexExpr->getType()->isSpecificBuiltinType(BuiltinType::Char_U)) 2280 && !IndexExpr->isTypeDependent()) 2281 Diag(LLoc, diag::warn_subscript_is_char) << IndexExpr->getSourceRange(); 2282 2283 // C99 6.5.2.1p1: "shall have type "pointer to *object* type". Similarly, 2284 // C++ [expr.sub]p1: The type "T" shall be a completely-defined object 2285 // type. Note that Functions are not objects, and that (in C99 parlance) 2286 // incomplete types are not object types. 2287 if (ResultType->isFunctionType()) { 2288 Diag(BaseExpr->getLocStart(), diag::err_subscript_function_type) 2289 << ResultType << BaseExpr->getSourceRange(); 2290 return ExprError(); 2291 } 2292 2293 if (!ResultType->isDependentType() && 2294 RequireCompleteType(LLoc, ResultType, 2295 PDiag(diag::err_subscript_incomplete_type) 2296 << BaseExpr->getSourceRange())) 2297 return ExprError(); 2298 2299 // Diagnose bad cases where we step over interface counts. 2300 if (ResultType->isObjCObjectType() && LangOpts.ObjCNonFragileABI) { 2301 Diag(LLoc, diag::err_subscript_nonfragile_interface) 2302 << ResultType << BaseExpr->getSourceRange(); 2303 return ExprError(); 2304 } 2305 2306 Base.release(); 2307 Idx.release(); 2308 return Owned(new (Context) ArraySubscriptExpr(LHSExp, RHSExp, 2309 ResultType, RLoc)); 2310} 2311 2312QualType Sema:: 2313CheckExtVectorComponent(QualType baseType, SourceLocation OpLoc, 2314 const IdentifierInfo *CompName, 2315 SourceLocation CompLoc) { 2316 // FIXME: Share logic with ExtVectorElementExpr::containsDuplicateElements, 2317 // see FIXME there. 2318 // 2319 // FIXME: This logic can be greatly simplified by splitting it along 2320 // halving/not halving and reworking the component checking. 2321 const ExtVectorType *vecType = baseType->getAs<ExtVectorType>(); 2322 2323 // The vector accessor can't exceed the number of elements. 2324 const char *compStr = CompName->getNameStart(); 2325 2326 // This flag determines whether or not the component is one of the four 2327 // special names that indicate a subset of exactly half the elements are 2328 // to be selected. 2329 bool HalvingSwizzle = false; 2330 2331 // This flag determines whether or not CompName has an 's' char prefix, 2332 // indicating that it is a string of hex values to be used as vector indices. 2333 bool HexSwizzle = *compStr == 's' || *compStr == 'S'; 2334 2335 // Check that we've found one of the special components, or that the component 2336 // names must come from the same set. 2337 if (!strcmp(compStr, "hi") || !strcmp(compStr, "lo") || 2338 !strcmp(compStr, "even") || !strcmp(compStr, "odd")) { 2339 HalvingSwizzle = true; 2340 } else if (vecType->getPointAccessorIdx(*compStr) != -1) { 2341 do 2342 compStr++; 2343 while (*compStr && vecType->getPointAccessorIdx(*compStr) != -1); 2344 } else if (HexSwizzle || vecType->getNumericAccessorIdx(*compStr) != -1) { 2345 do 2346 compStr++; 2347 while (*compStr && vecType->getNumericAccessorIdx(*compStr) != -1); 2348 } 2349 2350 if (!HalvingSwizzle && *compStr) { 2351 // We didn't get to the end of the string. This means the component names 2352 // didn't come from the same set *or* we encountered an illegal name. 2353 Diag(OpLoc, diag::err_ext_vector_component_name_illegal) 2354 << std::string(compStr,compStr+1) << SourceRange(CompLoc); 2355 return QualType(); 2356 } 2357 2358 // Ensure no component accessor exceeds the width of the vector type it 2359 // operates on. 2360 if (!HalvingSwizzle) { 2361 compStr = CompName->getNameStart(); 2362 2363 if (HexSwizzle) 2364 compStr++; 2365 2366 while (*compStr) { 2367 if (!vecType->isAccessorWithinNumElements(*compStr++)) { 2368 Diag(OpLoc, diag::err_ext_vector_component_exceeds_length) 2369 << baseType << SourceRange(CompLoc); 2370 return QualType(); 2371 } 2372 } 2373 } 2374 2375 // The component accessor looks fine - now we need to compute the actual type. 2376 // The vector type is implied by the component accessor. For example, 2377 // vec4.b is a float, vec4.xy is a vec2, vec4.rgb is a vec3, etc. 2378 // vec4.s0 is a float, vec4.s23 is a vec3, etc. 2379 // vec4.hi, vec4.lo, vec4.e, and vec4.o all return vec2. 2380 unsigned CompSize = HalvingSwizzle ? (vecType->getNumElements() + 1) / 2 2381 : CompName->getLength(); 2382 if (HexSwizzle) 2383 CompSize--; 2384 2385 if (CompSize == 1) 2386 return vecType->getElementType(); 2387 2388 QualType VT = Context.getExtVectorType(vecType->getElementType(), CompSize); 2389 // Now look up the TypeDefDecl from the vector type. Without this, 2390 // diagostics look bad. We want extended vector types to appear built-in. 2391 for (unsigned i = 0, E = ExtVectorDecls.size(); i != E; ++i) { 2392 if (ExtVectorDecls[i]->getUnderlyingType() == VT) 2393 return Context.getTypedefType(ExtVectorDecls[i]); 2394 } 2395 return VT; // should never get here (a typedef type should always be found). 2396} 2397 2398static Decl *FindGetterNameDeclFromProtocolList(const ObjCProtocolDecl*PDecl, 2399 IdentifierInfo *Member, 2400 const Selector &Sel, 2401 ASTContext &Context) { 2402 2403 if (ObjCPropertyDecl *PD = PDecl->FindPropertyDeclaration(Member)) 2404 return PD; 2405 if (ObjCMethodDecl *OMD = PDecl->getInstanceMethod(Sel)) 2406 return OMD; 2407 2408 for (ObjCProtocolDecl::protocol_iterator I = PDecl->protocol_begin(), 2409 E = PDecl->protocol_end(); I != E; ++I) { 2410 if (Decl *D = FindGetterNameDeclFromProtocolList(*I, Member, Sel, 2411 Context)) 2412 return D; 2413 } 2414 return 0; 2415} 2416 2417static Decl *FindGetterNameDecl(const ObjCObjectPointerType *QIdTy, 2418 IdentifierInfo *Member, 2419 const Selector &Sel, 2420 ASTContext &Context) { 2421 // Check protocols on qualified interfaces. 2422 Decl *GDecl = 0; 2423 for (ObjCObjectPointerType::qual_iterator I = QIdTy->qual_begin(), 2424 E = QIdTy->qual_end(); I != E; ++I) { 2425 if (ObjCPropertyDecl *PD = (*I)->FindPropertyDeclaration(Member)) { 2426 GDecl = PD; 2427 break; 2428 } 2429 // Also must look for a getter name which uses property syntax. 2430 if (ObjCMethodDecl *OMD = (*I)->getInstanceMethod(Sel)) { 2431 GDecl = OMD; 2432 break; 2433 } 2434 } 2435 if (!GDecl) { 2436 for (ObjCObjectPointerType::qual_iterator I = QIdTy->qual_begin(), 2437 E = QIdTy->qual_end(); I != E; ++I) { 2438 // Search in the protocol-qualifier list of current protocol. 2439 GDecl = FindGetterNameDeclFromProtocolList(*I, Member, Sel, Context); 2440 if (GDecl) 2441 return GDecl; 2442 } 2443 } 2444 return GDecl; 2445} 2446 2447Sema::OwningExprResult 2448Sema::ActOnDependentMemberExpr(ExprArg Base, QualType BaseType, 2449 bool IsArrow, SourceLocation OpLoc, 2450 const CXXScopeSpec &SS, 2451 NamedDecl *FirstQualifierInScope, 2452 DeclarationName Name, SourceLocation NameLoc, 2453 const TemplateArgumentListInfo *TemplateArgs) { 2454 Expr *BaseExpr = Base.takeAs<Expr>(); 2455 2456 // Even in dependent contexts, try to diagnose base expressions with 2457 // obviously wrong types, e.g.: 2458 // 2459 // T* t; 2460 // t.f; 2461 // 2462 // In Obj-C++, however, the above expression is valid, since it could be 2463 // accessing the 'f' property if T is an Obj-C interface. The extra check 2464 // allows this, while still reporting an error if T is a struct pointer. 2465 if (!IsArrow) { 2466 const PointerType *PT = BaseType->getAs<PointerType>(); 2467 if (PT && (!getLangOptions().ObjC1 || 2468 PT->getPointeeType()->isRecordType())) { 2469 assert(BaseExpr && "cannot happen with implicit member accesses"); 2470 Diag(NameLoc, diag::err_typecheck_member_reference_struct_union) 2471 << BaseType << BaseExpr->getSourceRange(); 2472 return ExprError(); 2473 } 2474 } 2475 2476 assert(BaseType->isDependentType() || Name.isDependentName() || 2477 isDependentScopeSpecifier(SS)); 2478 2479 // Get the type being accessed in BaseType. If this is an arrow, the BaseExpr 2480 // must have pointer type, and the accessed type is the pointee. 2481 return Owned(CXXDependentScopeMemberExpr::Create(Context, BaseExpr, BaseType, 2482 IsArrow, OpLoc, 2483 static_cast<NestedNameSpecifier*>(SS.getScopeRep()), 2484 SS.getRange(), 2485 FirstQualifierInScope, 2486 Name, NameLoc, 2487 TemplateArgs)); 2488} 2489 2490/// We know that the given qualified member reference points only to 2491/// declarations which do not belong to the static type of the base 2492/// expression. Diagnose the problem. 2493static void DiagnoseQualifiedMemberReference(Sema &SemaRef, 2494 Expr *BaseExpr, 2495 QualType BaseType, 2496 const CXXScopeSpec &SS, 2497 const LookupResult &R) { 2498 // If this is an implicit member access, use a different set of 2499 // diagnostics. 2500 if (!BaseExpr) 2501 return DiagnoseInstanceReference(SemaRef, SS, R); 2502 2503 SemaRef.Diag(R.getNameLoc(), diag::err_qualified_member_of_unrelated) 2504 << SS.getRange() << R.getRepresentativeDecl() << BaseType; 2505} 2506 2507// Check whether the declarations we found through a nested-name 2508// specifier in a member expression are actually members of the base 2509// type. The restriction here is: 2510// 2511// C++ [expr.ref]p2: 2512// ... In these cases, the id-expression shall name a 2513// member of the class or of one of its base classes. 2514// 2515// So it's perfectly legitimate for the nested-name specifier to name 2516// an unrelated class, and for us to find an overload set including 2517// decls from classes which are not superclasses, as long as the decl 2518// we actually pick through overload resolution is from a superclass. 2519bool Sema::CheckQualifiedMemberReference(Expr *BaseExpr, 2520 QualType BaseType, 2521 const CXXScopeSpec &SS, 2522 const LookupResult &R) { 2523 const RecordType *BaseRT = BaseType->getAs<RecordType>(); 2524 if (!BaseRT) { 2525 // We can't check this yet because the base type is still 2526 // dependent. 2527 assert(BaseType->isDependentType()); 2528 return false; 2529 } 2530 CXXRecordDecl *BaseRecord = cast<CXXRecordDecl>(BaseRT->getDecl()); 2531 2532 for (LookupResult::iterator I = R.begin(), E = R.end(); I != E; ++I) { 2533 // If this is an implicit member reference and we find a 2534 // non-instance member, it's not an error. 2535 if (!BaseExpr && !(*I)->isCXXInstanceMember()) 2536 return false; 2537 2538 // Note that we use the DC of the decl, not the underlying decl. 2539 CXXRecordDecl *RecordD = cast<CXXRecordDecl>((*I)->getDeclContext()); 2540 while (RecordD->isAnonymousStructOrUnion()) 2541 RecordD = cast<CXXRecordDecl>(RecordD->getParent()); 2542 2543 llvm::SmallPtrSet<CXXRecordDecl*,4> MemberRecord; 2544 MemberRecord.insert(RecordD->getCanonicalDecl()); 2545 2546 if (!IsProvablyNotDerivedFrom(*this, BaseRecord, MemberRecord)) 2547 return false; 2548 } 2549 2550 DiagnoseQualifiedMemberReference(*this, BaseExpr, BaseType, SS, R); 2551 return true; 2552} 2553 2554static bool 2555LookupMemberExprInRecord(Sema &SemaRef, LookupResult &R, 2556 SourceRange BaseRange, const RecordType *RTy, 2557 SourceLocation OpLoc, CXXScopeSpec &SS) { 2558 RecordDecl *RDecl = RTy->getDecl(); 2559 if (SemaRef.RequireCompleteType(OpLoc, QualType(RTy, 0), 2560 SemaRef.PDiag(diag::err_typecheck_incomplete_tag) 2561 << BaseRange)) 2562 return true; 2563 2564 DeclContext *DC = RDecl; 2565 if (SS.isSet()) { 2566 // If the member name was a qualified-id, look into the 2567 // nested-name-specifier. 2568 DC = SemaRef.computeDeclContext(SS, false); 2569 2570 if (SemaRef.RequireCompleteDeclContext(SS, DC)) { 2571 SemaRef.Diag(SS.getRange().getEnd(), diag::err_typecheck_incomplete_tag) 2572 << SS.getRange() << DC; 2573 return true; 2574 } 2575 2576 assert(DC && "Cannot handle non-computable dependent contexts in lookup"); 2577 2578 if (!isa<TypeDecl>(DC)) { 2579 SemaRef.Diag(R.getNameLoc(), diag::err_qualified_member_nonclass) 2580 << DC << SS.getRange(); 2581 return true; 2582 } 2583 } 2584 2585 // The record definition is complete, now look up the member. 2586 SemaRef.LookupQualifiedName(R, DC); 2587 2588 if (!R.empty()) 2589 return false; 2590 2591 // We didn't find anything with the given name, so try to correct 2592 // for typos. 2593 DeclarationName Name = R.getLookupName(); 2594 if (SemaRef.CorrectTypo(R, 0, &SS, DC, false, Sema::CTC_MemberLookup) && 2595 !R.empty() && 2596 (isa<ValueDecl>(*R.begin()) || isa<FunctionTemplateDecl>(*R.begin()))) { 2597 SemaRef.Diag(R.getNameLoc(), diag::err_no_member_suggest) 2598 << Name << DC << R.getLookupName() << SS.getRange() 2599 << FixItHint::CreateReplacement(R.getNameLoc(), 2600 R.getLookupName().getAsString()); 2601 if (NamedDecl *ND = R.getAsSingle<NamedDecl>()) 2602 SemaRef.Diag(ND->getLocation(), diag::note_previous_decl) 2603 << ND->getDeclName(); 2604 return false; 2605 } else { 2606 R.clear(); 2607 } 2608 2609 return false; 2610} 2611 2612Sema::OwningExprResult 2613Sema::BuildMemberReferenceExpr(ExprArg BaseArg, QualType BaseType, 2614 SourceLocation OpLoc, bool IsArrow, 2615 CXXScopeSpec &SS, 2616 NamedDecl *FirstQualifierInScope, 2617 DeclarationName Name, SourceLocation NameLoc, 2618 const TemplateArgumentListInfo *TemplateArgs) { 2619 Expr *Base = BaseArg.takeAs<Expr>(); 2620 2621 if (BaseType->isDependentType() || 2622 (SS.isSet() && isDependentScopeSpecifier(SS))) 2623 return ActOnDependentMemberExpr(ExprArg(*this, Base), BaseType, 2624 IsArrow, OpLoc, 2625 SS, FirstQualifierInScope, 2626 Name, NameLoc, 2627 TemplateArgs); 2628 2629 LookupResult R(*this, Name, NameLoc, LookupMemberName); 2630 2631 // Implicit member accesses. 2632 if (!Base) { 2633 QualType RecordTy = BaseType; 2634 if (IsArrow) RecordTy = RecordTy->getAs<PointerType>()->getPointeeType(); 2635 if (LookupMemberExprInRecord(*this, R, SourceRange(), 2636 RecordTy->getAs<RecordType>(), 2637 OpLoc, SS)) 2638 return ExprError(); 2639 2640 // Explicit member accesses. 2641 } else { 2642 OwningExprResult Result = 2643 LookupMemberExpr(R, Base, IsArrow, OpLoc, 2644 SS, /*ObjCImpDecl*/ DeclPtrTy()); 2645 2646 if (Result.isInvalid()) { 2647 Owned(Base); 2648 return ExprError(); 2649 } 2650 2651 if (Result.get()) 2652 return move(Result); 2653 2654 // LookupMemberExpr can modify Base, and thus change BaseType 2655 BaseType = Base->getType(); 2656 } 2657 2658 return BuildMemberReferenceExpr(ExprArg(*this, Base), BaseType, 2659 OpLoc, IsArrow, SS, FirstQualifierInScope, 2660 R, TemplateArgs); 2661} 2662 2663Sema::OwningExprResult 2664Sema::BuildMemberReferenceExpr(ExprArg Base, QualType BaseExprType, 2665 SourceLocation OpLoc, bool IsArrow, 2666 const CXXScopeSpec &SS, 2667 NamedDecl *FirstQualifierInScope, 2668 LookupResult &R, 2669 const TemplateArgumentListInfo *TemplateArgs, 2670 bool SuppressQualifierCheck) { 2671 Expr *BaseExpr = Base.takeAs<Expr>(); 2672 QualType BaseType = BaseExprType; 2673 if (IsArrow) { 2674 assert(BaseType->isPointerType()); 2675 BaseType = BaseType->getAs<PointerType>()->getPointeeType(); 2676 } 2677 R.setBaseObjectType(BaseType); 2678 2679 NestedNameSpecifier *Qualifier = 2680 static_cast<NestedNameSpecifier*>(SS.getScopeRep()); 2681 DeclarationName MemberName = R.getLookupName(); 2682 SourceLocation MemberLoc = R.getNameLoc(); 2683 2684 if (R.isAmbiguous()) 2685 return ExprError(); 2686 2687 if (R.empty()) { 2688 // Rederive where we looked up. 2689 DeclContext *DC = (SS.isSet() 2690 ? computeDeclContext(SS, false) 2691 : BaseType->getAs<RecordType>()->getDecl()); 2692 2693 Diag(R.getNameLoc(), diag::err_no_member) 2694 << MemberName << DC 2695 << (BaseExpr ? BaseExpr->getSourceRange() : SourceRange()); 2696 return ExprError(); 2697 } 2698 2699 // Diagnose lookups that find only declarations from a non-base 2700 // type. This is possible for either qualified lookups (which may 2701 // have been qualified with an unrelated type) or implicit member 2702 // expressions (which were found with unqualified lookup and thus 2703 // may have come from an enclosing scope). Note that it's okay for 2704 // lookup to find declarations from a non-base type as long as those 2705 // aren't the ones picked by overload resolution. 2706 if ((SS.isSet() || !BaseExpr || 2707 (isa<CXXThisExpr>(BaseExpr) && 2708 cast<CXXThisExpr>(BaseExpr)->isImplicit())) && 2709 !SuppressQualifierCheck && 2710 CheckQualifiedMemberReference(BaseExpr, BaseType, SS, R)) 2711 return ExprError(); 2712 2713 // Construct an unresolved result if we in fact got an unresolved 2714 // result. 2715 if (R.isOverloadedResult() || R.isUnresolvableResult()) { 2716 bool Dependent = 2717 BaseExprType->isDependentType() || 2718 R.isUnresolvableResult() || 2719 OverloadExpr::ComputeDependence(R.begin(), R.end(), TemplateArgs); 2720 2721 // Suppress any lookup-related diagnostics; we'll do these when we 2722 // pick a member. 2723 R.suppressDiagnostics(); 2724 2725 UnresolvedMemberExpr *MemExpr 2726 = UnresolvedMemberExpr::Create(Context, Dependent, 2727 R.isUnresolvableResult(), 2728 BaseExpr, BaseExprType, 2729 IsArrow, OpLoc, 2730 Qualifier, SS.getRange(), 2731 MemberName, MemberLoc, 2732 TemplateArgs, R.begin(), R.end()); 2733 2734 return Owned(MemExpr); 2735 } 2736 2737 assert(R.isSingleResult()); 2738 DeclAccessPair FoundDecl = R.begin().getPair(); 2739 NamedDecl *MemberDecl = R.getFoundDecl(); 2740 2741 // FIXME: diagnose the presence of template arguments now. 2742 2743 // If the decl being referenced had an error, return an error for this 2744 // sub-expr without emitting another error, in order to avoid cascading 2745 // error cases. 2746 if (MemberDecl->isInvalidDecl()) 2747 return ExprError(); 2748 2749 // Handle the implicit-member-access case. 2750 if (!BaseExpr) { 2751 // If this is not an instance member, convert to a non-member access. 2752 if (!MemberDecl->isCXXInstanceMember()) 2753 return BuildDeclarationNameExpr(SS, R.getNameLoc(), MemberDecl); 2754 2755 SourceLocation Loc = R.getNameLoc(); 2756 if (SS.getRange().isValid()) 2757 Loc = SS.getRange().getBegin(); 2758 BaseExpr = new (Context) CXXThisExpr(Loc, BaseExprType,/*isImplicit=*/true); 2759 } 2760 2761 bool ShouldCheckUse = true; 2762 if (CXXMethodDecl *MD = dyn_cast<CXXMethodDecl>(MemberDecl)) { 2763 // Don't diagnose the use of a virtual member function unless it's 2764 // explicitly qualified. 2765 if (MD->isVirtual() && !SS.isSet()) 2766 ShouldCheckUse = false; 2767 } 2768 2769 // Check the use of this member. 2770 if (ShouldCheckUse && DiagnoseUseOfDecl(MemberDecl, MemberLoc)) { 2771 Owned(BaseExpr); 2772 return ExprError(); 2773 } 2774 2775 if (FieldDecl *FD = dyn_cast<FieldDecl>(MemberDecl)) { 2776 // We may have found a field within an anonymous union or struct 2777 // (C++ [class.union]). 2778 if (cast<RecordDecl>(FD->getDeclContext())->isAnonymousStructOrUnion() && 2779 !BaseType->getAs<RecordType>()->getDecl()->isAnonymousStructOrUnion()) 2780 return BuildAnonymousStructUnionMemberReference(MemberLoc, FD, 2781 BaseExpr, OpLoc); 2782 2783 // Figure out the type of the member; see C99 6.5.2.3p3, C++ [expr.ref] 2784 QualType MemberType = FD->getType(); 2785 if (const ReferenceType *Ref = MemberType->getAs<ReferenceType>()) 2786 MemberType = Ref->getPointeeType(); 2787 else { 2788 Qualifiers BaseQuals = BaseType.getQualifiers(); 2789 BaseQuals.removeObjCGCAttr(); 2790 if (FD->isMutable()) BaseQuals.removeConst(); 2791 2792 Qualifiers MemberQuals 2793 = Context.getCanonicalType(MemberType).getQualifiers(); 2794 2795 Qualifiers Combined = BaseQuals + MemberQuals; 2796 if (Combined != MemberQuals) 2797 MemberType = Context.getQualifiedType(MemberType, Combined); 2798 } 2799 2800 MarkDeclarationReferenced(MemberLoc, FD); 2801 if (PerformObjectMemberConversion(BaseExpr, Qualifier, FoundDecl, FD)) 2802 return ExprError(); 2803 return Owned(BuildMemberExpr(Context, BaseExpr, IsArrow, SS, 2804 FD, FoundDecl, MemberLoc, MemberType)); 2805 } 2806 2807 if (VarDecl *Var = dyn_cast<VarDecl>(MemberDecl)) { 2808 MarkDeclarationReferenced(MemberLoc, Var); 2809 return Owned(BuildMemberExpr(Context, BaseExpr, IsArrow, SS, 2810 Var, FoundDecl, MemberLoc, 2811 Var->getType().getNonReferenceType())); 2812 } 2813 2814 if (FunctionDecl *MemberFn = dyn_cast<FunctionDecl>(MemberDecl)) { 2815 MarkDeclarationReferenced(MemberLoc, MemberDecl); 2816 return Owned(BuildMemberExpr(Context, BaseExpr, IsArrow, SS, 2817 MemberFn, FoundDecl, MemberLoc, 2818 MemberFn->getType())); 2819 } 2820 2821 if (EnumConstantDecl *Enum = dyn_cast<EnumConstantDecl>(MemberDecl)) { 2822 MarkDeclarationReferenced(MemberLoc, MemberDecl); 2823 return Owned(BuildMemberExpr(Context, BaseExpr, IsArrow, SS, 2824 Enum, FoundDecl, MemberLoc, Enum->getType())); 2825 } 2826 2827 Owned(BaseExpr); 2828 2829 // We found something that we didn't expect. Complain. 2830 if (isa<TypeDecl>(MemberDecl)) 2831 Diag(MemberLoc,diag::err_typecheck_member_reference_type) 2832 << MemberName << BaseType << int(IsArrow); 2833 else 2834 Diag(MemberLoc, diag::err_typecheck_member_reference_unknown) 2835 << MemberName << BaseType << int(IsArrow); 2836 2837 Diag(MemberDecl->getLocation(), diag::note_member_declared_here) 2838 << MemberName; 2839 R.suppressDiagnostics(); 2840 return ExprError(); 2841} 2842 2843/// Look up the given member of the given non-type-dependent 2844/// expression. This can return in one of two ways: 2845/// * If it returns a sentinel null-but-valid result, the caller will 2846/// assume that lookup was performed and the results written into 2847/// the provided structure. It will take over from there. 2848/// * Otherwise, the returned expression will be produced in place of 2849/// an ordinary member expression. 2850/// 2851/// The ObjCImpDecl bit is a gross hack that will need to be properly 2852/// fixed for ObjC++. 2853Sema::OwningExprResult 2854Sema::LookupMemberExpr(LookupResult &R, Expr *&BaseExpr, 2855 bool &IsArrow, SourceLocation OpLoc, 2856 CXXScopeSpec &SS, 2857 DeclPtrTy ObjCImpDecl) { 2858 assert(BaseExpr && "no base expression"); 2859 2860 // Perform default conversions. 2861 DefaultFunctionArrayConversion(BaseExpr); 2862 2863 QualType BaseType = BaseExpr->getType(); 2864 assert(!BaseType->isDependentType()); 2865 2866 DeclarationName MemberName = R.getLookupName(); 2867 SourceLocation MemberLoc = R.getNameLoc(); 2868 2869 // If the user is trying to apply -> or . to a function pointer 2870 // type, it's probably because they forgot parentheses to call that 2871 // function. Suggest the addition of those parentheses, build the 2872 // call, and continue on. 2873 if (const PointerType *Ptr = BaseType->getAs<PointerType>()) { 2874 if (const FunctionProtoType *Fun 2875 = Ptr->getPointeeType()->getAs<FunctionProtoType>()) { 2876 QualType ResultTy = Fun->getResultType(); 2877 if (Fun->getNumArgs() == 0 && 2878 ((!IsArrow && ResultTy->isRecordType()) || 2879 (IsArrow && ResultTy->isPointerType() && 2880 ResultTy->getAs<PointerType>()->getPointeeType() 2881 ->isRecordType()))) { 2882 SourceLocation Loc = PP.getLocForEndOfToken(BaseExpr->getLocEnd()); 2883 Diag(Loc, diag::err_member_reference_needs_call) 2884 << QualType(Fun, 0) 2885 << FixItHint::CreateInsertion(Loc, "()"); 2886 2887 OwningExprResult NewBase 2888 = ActOnCallExpr(0, ExprArg(*this, BaseExpr), Loc, 2889 MultiExprArg(*this, 0, 0), 0, Loc); 2890 if (NewBase.isInvalid()) 2891 return ExprError(); 2892 2893 BaseExpr = NewBase.takeAs<Expr>(); 2894 DefaultFunctionArrayConversion(BaseExpr); 2895 BaseType = BaseExpr->getType(); 2896 } 2897 } 2898 } 2899 2900 // If this is an Objective-C pseudo-builtin and a definition is provided then 2901 // use that. 2902 if (BaseType->isObjCIdType()) { 2903 if (IsArrow) { 2904 // Handle the following exceptional case PObj->isa. 2905 if (const ObjCObjectPointerType *OPT = 2906 BaseType->getAs<ObjCObjectPointerType>()) { 2907 if (OPT->getObjectType()->isObjCId() && 2908 MemberName.getAsIdentifierInfo()->isStr("isa")) 2909 return Owned(new (Context) ObjCIsaExpr(BaseExpr, true, MemberLoc, 2910 Context.getObjCClassType())); 2911 } 2912 } 2913 // We have an 'id' type. Rather than fall through, we check if this 2914 // is a reference to 'isa'. 2915 if (BaseType != Context.ObjCIdRedefinitionType) { 2916 BaseType = Context.ObjCIdRedefinitionType; 2917 ImpCastExprToType(BaseExpr, BaseType, CastExpr::CK_BitCast); 2918 } 2919 } 2920 2921 // If this is an Objective-C pseudo-builtin and a definition is provided then 2922 // use that. 2923 if (Context.isObjCSelType(BaseType)) { 2924 // We have an 'SEL' type. Rather than fall through, we check if this 2925 // is a reference to 'sel_id'. 2926 if (BaseType != Context.ObjCSelRedefinitionType) { 2927 BaseType = Context.ObjCSelRedefinitionType; 2928 ImpCastExprToType(BaseExpr, BaseType, CastExpr::CK_BitCast); 2929 } 2930 } 2931 2932 assert(!BaseType.isNull() && "no type for member expression"); 2933 2934 // Handle properties on ObjC 'Class' types. 2935 if (!IsArrow && BaseType->isObjCClassType()) { 2936 // Also must look for a getter name which uses property syntax. 2937 IdentifierInfo *Member = MemberName.getAsIdentifierInfo(); 2938 Selector Sel = PP.getSelectorTable().getNullarySelector(Member); 2939 if (ObjCMethodDecl *MD = getCurMethodDecl()) { 2940 ObjCInterfaceDecl *IFace = MD->getClassInterface(); 2941 ObjCMethodDecl *Getter; 2942 // FIXME: need to also look locally in the implementation. 2943 if ((Getter = IFace->lookupClassMethod(Sel))) { 2944 // Check the use of this method. 2945 if (DiagnoseUseOfDecl(Getter, MemberLoc)) 2946 return ExprError(); 2947 } 2948 // If we found a getter then this may be a valid dot-reference, we 2949 // will look for the matching setter, in case it is needed. 2950 Selector SetterSel = 2951 SelectorTable::constructSetterName(PP.getIdentifierTable(), 2952 PP.getSelectorTable(), Member); 2953 ObjCMethodDecl *Setter = IFace->lookupClassMethod(SetterSel); 2954 if (!Setter) { 2955 // If this reference is in an @implementation, also check for 'private' 2956 // methods. 2957 Setter = IFace->lookupPrivateInstanceMethod(SetterSel); 2958 } 2959 // Look through local category implementations associated with the class. 2960 if (!Setter) 2961 Setter = IFace->getCategoryClassMethod(SetterSel); 2962 2963 if (Setter && DiagnoseUseOfDecl(Setter, MemberLoc)) 2964 return ExprError(); 2965 2966 if (Getter || Setter) { 2967 QualType PType; 2968 2969 if (Getter) 2970 PType = Getter->getResultType(); 2971 else 2972 // Get the expression type from Setter's incoming parameter. 2973 PType = (*(Setter->param_end() -1))->getType(); 2974 // FIXME: we must check that the setter has property type. 2975 return Owned(new (Context) ObjCImplicitSetterGetterRefExpr(Getter, 2976 PType, 2977 Setter, MemberLoc, BaseExpr)); 2978 } 2979 return ExprError(Diag(MemberLoc, diag::err_property_not_found) 2980 << MemberName << BaseType); 2981 } 2982 } 2983 2984 if (BaseType->isObjCClassType() && 2985 BaseType != Context.ObjCClassRedefinitionType) { 2986 BaseType = Context.ObjCClassRedefinitionType; 2987 ImpCastExprToType(BaseExpr, BaseType, CastExpr::CK_BitCast); 2988 } 2989 2990 if (IsArrow) { 2991 if (const PointerType *PT = BaseType->getAs<PointerType>()) 2992 BaseType = PT->getPointeeType(); 2993 else if (BaseType->isObjCObjectPointerType()) 2994 ; 2995 else if (BaseType->isRecordType()) { 2996 // Recover from arrow accesses to records, e.g.: 2997 // struct MyRecord foo; 2998 // foo->bar 2999 // This is actually well-formed in C++ if MyRecord has an 3000 // overloaded operator->, but that should have been dealt with 3001 // by now. 3002 Diag(OpLoc, diag::err_typecheck_member_reference_suggestion) 3003 << BaseType << int(IsArrow) << BaseExpr->getSourceRange() 3004 << FixItHint::CreateReplacement(OpLoc, "."); 3005 IsArrow = false; 3006 } else { 3007 Diag(MemberLoc, diag::err_typecheck_member_reference_arrow) 3008 << BaseType << BaseExpr->getSourceRange(); 3009 return ExprError(); 3010 } 3011 } else { 3012 // Recover from dot accesses to pointers, e.g.: 3013 // type *foo; 3014 // foo.bar 3015 // This is actually well-formed in two cases: 3016 // - 'type' is an Objective C type 3017 // - 'bar' is a pseudo-destructor name which happens to refer to 3018 // the appropriate pointer type 3019 if (MemberName.getNameKind() != DeclarationName::CXXDestructorName) { 3020 const PointerType *PT = BaseType->getAs<PointerType>(); 3021 if (PT && PT->getPointeeType()->isRecordType()) { 3022 Diag(OpLoc, diag::err_typecheck_member_reference_suggestion) 3023 << BaseType << int(IsArrow) << BaseExpr->getSourceRange() 3024 << FixItHint::CreateReplacement(OpLoc, "->"); 3025 BaseType = PT->getPointeeType(); 3026 IsArrow = true; 3027 } 3028 } 3029 } 3030 3031 // Handle field access to simple records. 3032 if (const RecordType *RTy = BaseType->getAs<RecordType>()) { 3033 if (LookupMemberExprInRecord(*this, R, BaseExpr->getSourceRange(), 3034 RTy, OpLoc, SS)) 3035 return ExprError(); 3036 return Owned((Expr*) 0); 3037 } 3038 3039 // Handle access to Objective-C instance variables, such as "Obj->ivar" and 3040 // (*Obj).ivar. 3041 if ((IsArrow && BaseType->isObjCObjectPointerType()) || 3042 (!IsArrow && BaseType->isObjCObjectType())) { 3043 const ObjCObjectPointerType *OPT = BaseType->getAs<ObjCObjectPointerType>(); 3044 ObjCInterfaceDecl *IDecl = 3045 OPT ? OPT->getInterfaceDecl() 3046 : BaseType->getAs<ObjCObjectType>()->getInterface(); 3047 if (IDecl) { 3048 IdentifierInfo *Member = MemberName.getAsIdentifierInfo(); 3049 3050 ObjCInterfaceDecl *ClassDeclared; 3051 ObjCIvarDecl *IV = IDecl->lookupInstanceVariable(Member, ClassDeclared); 3052 3053 if (!IV) { 3054 // Attempt to correct for typos in ivar names. 3055 LookupResult Res(*this, R.getLookupName(), R.getNameLoc(), 3056 LookupMemberName); 3057 if (CorrectTypo(Res, 0, 0, IDecl, false, CTC_MemberLookup) && 3058 (IV = Res.getAsSingle<ObjCIvarDecl>())) { 3059 Diag(R.getNameLoc(), 3060 diag::err_typecheck_member_reference_ivar_suggest) 3061 << IDecl->getDeclName() << MemberName << IV->getDeclName() 3062 << FixItHint::CreateReplacement(R.getNameLoc(), 3063 IV->getNameAsString()); 3064 Diag(IV->getLocation(), diag::note_previous_decl) 3065 << IV->getDeclName(); 3066 } 3067 } 3068 3069 if (IV) { 3070 // If the decl being referenced had an error, return an error for this 3071 // sub-expr without emitting another error, in order to avoid cascading 3072 // error cases. 3073 if (IV->isInvalidDecl()) 3074 return ExprError(); 3075 3076 // Check whether we can reference this field. 3077 if (DiagnoseUseOfDecl(IV, MemberLoc)) 3078 return ExprError(); 3079 if (IV->getAccessControl() != ObjCIvarDecl::Public && 3080 IV->getAccessControl() != ObjCIvarDecl::Package) { 3081 ObjCInterfaceDecl *ClassOfMethodDecl = 0; 3082 if (ObjCMethodDecl *MD = getCurMethodDecl()) 3083 ClassOfMethodDecl = MD->getClassInterface(); 3084 else if (ObjCImpDecl && getCurFunctionDecl()) { 3085 // Case of a c-function declared inside an objc implementation. 3086 // FIXME: For a c-style function nested inside an objc implementation 3087 // class, there is no implementation context available, so we pass 3088 // down the context as argument to this routine. Ideally, this context 3089 // need be passed down in the AST node and somehow calculated from the 3090 // AST for a function decl. 3091 Decl *ImplDecl = ObjCImpDecl.getAs<Decl>(); 3092 if (ObjCImplementationDecl *IMPD = 3093 dyn_cast<ObjCImplementationDecl>(ImplDecl)) 3094 ClassOfMethodDecl = IMPD->getClassInterface(); 3095 else if (ObjCCategoryImplDecl* CatImplClass = 3096 dyn_cast<ObjCCategoryImplDecl>(ImplDecl)) 3097 ClassOfMethodDecl = CatImplClass->getClassInterface(); 3098 } 3099 3100 if (IV->getAccessControl() == ObjCIvarDecl::Private) { 3101 if (ClassDeclared != IDecl || 3102 ClassOfMethodDecl != ClassDeclared) 3103 Diag(MemberLoc, diag::error_private_ivar_access) 3104 << IV->getDeclName(); 3105 } else if (!IDecl->isSuperClassOf(ClassOfMethodDecl)) 3106 // @protected 3107 Diag(MemberLoc, diag::error_protected_ivar_access) 3108 << IV->getDeclName(); 3109 } 3110 3111 return Owned(new (Context) ObjCIvarRefExpr(IV, IV->getType(), 3112 MemberLoc, BaseExpr, 3113 IsArrow)); 3114 } 3115 return ExprError(Diag(MemberLoc, diag::err_typecheck_member_reference_ivar) 3116 << IDecl->getDeclName() << MemberName 3117 << BaseExpr->getSourceRange()); 3118 } 3119 } 3120 // Handle properties on 'id' and qualified "id". 3121 if (!IsArrow && (BaseType->isObjCIdType() || 3122 BaseType->isObjCQualifiedIdType())) { 3123 const ObjCObjectPointerType *QIdTy = BaseType->getAs<ObjCObjectPointerType>(); 3124 IdentifierInfo *Member = MemberName.getAsIdentifierInfo(); 3125 3126 // Check protocols on qualified interfaces. 3127 Selector Sel = PP.getSelectorTable().getNullarySelector(Member); 3128 if (Decl *PMDecl = FindGetterNameDecl(QIdTy, Member, Sel, Context)) { 3129 if (ObjCPropertyDecl *PD = dyn_cast<ObjCPropertyDecl>(PMDecl)) { 3130 // Check the use of this declaration 3131 if (DiagnoseUseOfDecl(PD, MemberLoc)) 3132 return ExprError(); 3133 3134 return Owned(new (Context) ObjCPropertyRefExpr(PD, PD->getType(), 3135 MemberLoc, BaseExpr)); 3136 } 3137 if (ObjCMethodDecl *OMD = dyn_cast<ObjCMethodDecl>(PMDecl)) { 3138 // Check the use of this method. 3139 if (DiagnoseUseOfDecl(OMD, MemberLoc)) 3140 return ExprError(); 3141 3142 return Owned(ObjCMessageExpr::Create(Context, 3143 OMD->getResultType().getNonReferenceType(), 3144 OpLoc, BaseExpr, Sel, 3145 OMD, NULL, 0, MemberLoc)); 3146 } 3147 } 3148 3149 return ExprError(Diag(MemberLoc, diag::err_property_not_found) 3150 << MemberName << BaseType); 3151 } 3152 3153 // Handle Objective-C property access, which is "Obj.property" where Obj is a 3154 // pointer to a (potentially qualified) interface type. 3155 if (!IsArrow) 3156 if (const ObjCObjectPointerType *OPT = 3157 BaseType->getAsObjCInterfacePointerType()) 3158 return HandleExprPropertyRefExpr(OPT, BaseExpr, MemberName, MemberLoc); 3159 3160 // Handle the following exceptional case (*Obj).isa. 3161 if (!IsArrow && 3162 BaseType->isObjCObjectType() && 3163 BaseType->getAs<ObjCObjectType>()->isObjCId() && 3164 MemberName.getAsIdentifierInfo()->isStr("isa")) 3165 return Owned(new (Context) ObjCIsaExpr(BaseExpr, false, MemberLoc, 3166 Context.getObjCClassType())); 3167 3168 // Handle 'field access' to vectors, such as 'V.xx'. 3169 if (BaseType->isExtVectorType()) { 3170 IdentifierInfo *Member = MemberName.getAsIdentifierInfo(); 3171 QualType ret = CheckExtVectorComponent(BaseType, OpLoc, Member, MemberLoc); 3172 if (ret.isNull()) 3173 return ExprError(); 3174 return Owned(new (Context) ExtVectorElementExpr(ret, BaseExpr, *Member, 3175 MemberLoc)); 3176 } 3177 3178 Diag(MemberLoc, diag::err_typecheck_member_reference_struct_union) 3179 << BaseType << BaseExpr->getSourceRange(); 3180 3181 return ExprError(); 3182} 3183 3184/// The main callback when the parser finds something like 3185/// expression . [nested-name-specifier] identifier 3186/// expression -> [nested-name-specifier] identifier 3187/// where 'identifier' encompasses a fairly broad spectrum of 3188/// possibilities, including destructor and operator references. 3189/// 3190/// \param OpKind either tok::arrow or tok::period 3191/// \param HasTrailingLParen whether the next token is '(', which 3192/// is used to diagnose mis-uses of special members that can 3193/// only be called 3194/// \param ObjCImpDecl the current ObjC @implementation decl; 3195/// this is an ugly hack around the fact that ObjC @implementations 3196/// aren't properly put in the context chain 3197Sema::OwningExprResult Sema::ActOnMemberAccessExpr(Scope *S, ExprArg BaseArg, 3198 SourceLocation OpLoc, 3199 tok::TokenKind OpKind, 3200 CXXScopeSpec &SS, 3201 UnqualifiedId &Id, 3202 DeclPtrTy ObjCImpDecl, 3203 bool HasTrailingLParen) { 3204 if (SS.isSet() && SS.isInvalid()) 3205 return ExprError(); 3206 3207 TemplateArgumentListInfo TemplateArgsBuffer; 3208 3209 // Decompose the name into its component parts. 3210 DeclarationName Name; 3211 SourceLocation NameLoc; 3212 const TemplateArgumentListInfo *TemplateArgs; 3213 DecomposeUnqualifiedId(*this, Id, TemplateArgsBuffer, 3214 Name, NameLoc, TemplateArgs); 3215 3216 bool IsArrow = (OpKind == tok::arrow); 3217 3218 NamedDecl *FirstQualifierInScope 3219 = (!SS.isSet() ? 0 : FindFirstQualifierInScope(S, 3220 static_cast<NestedNameSpecifier*>(SS.getScopeRep()))); 3221 3222 // This is a postfix expression, so get rid of ParenListExprs. 3223 BaseArg = MaybeConvertParenListExprToParenExpr(S, move(BaseArg)); 3224 3225 Expr *Base = BaseArg.takeAs<Expr>(); 3226 OwningExprResult Result(*this); 3227 if (Base->getType()->isDependentType() || Name.isDependentName() || 3228 isDependentScopeSpecifier(SS)) { 3229 Result = ActOnDependentMemberExpr(ExprArg(*this, Base), Base->getType(), 3230 IsArrow, OpLoc, 3231 SS, FirstQualifierInScope, 3232 Name, NameLoc, 3233 TemplateArgs); 3234 } else { 3235 LookupResult R(*this, Name, NameLoc, LookupMemberName); 3236 if (TemplateArgs) { 3237 // Re-use the lookup done for the template name. 3238 DecomposeTemplateName(R, Id); 3239 3240 // Re-derive the naming class. 3241 if (SS.isSet()) { 3242 NestedNameSpecifier *Qualifier 3243 = static_cast<NestedNameSpecifier *>(SS.getScopeRep()); 3244 if (const Type *Ty = Qualifier->getAsType()) 3245 if (CXXRecordDecl *NamingClass = Ty->getAsCXXRecordDecl()) 3246 R.setNamingClass(NamingClass); 3247 } else { 3248 QualType BaseType = Base->getType(); 3249 if (const PointerType *Ptr = BaseType->getAs<PointerType>()) 3250 BaseType = Ptr->getPointeeType(); 3251 if (CXXRecordDecl *NamingClass = BaseType->getAsCXXRecordDecl()) 3252 R.setNamingClass(NamingClass); 3253 } 3254 } else { 3255 Result = LookupMemberExpr(R, Base, IsArrow, OpLoc, 3256 SS, ObjCImpDecl); 3257 3258 if (Result.isInvalid()) { 3259 Owned(Base); 3260 return ExprError(); 3261 } 3262 3263 if (Result.get()) { 3264 // The only way a reference to a destructor can be used is to 3265 // immediately call it, which falls into this case. If the 3266 // next token is not a '(', produce a diagnostic and build the 3267 // call now. 3268 if (!HasTrailingLParen && 3269 Id.getKind() == UnqualifiedId::IK_DestructorName) 3270 return DiagnoseDtorReference(NameLoc, move(Result)); 3271 3272 return move(Result); 3273 } 3274 } 3275 3276 Result = BuildMemberReferenceExpr(ExprArg(*this, Base), Base->getType(), 3277 OpLoc, IsArrow, SS, FirstQualifierInScope, 3278 R, TemplateArgs); 3279 } 3280 3281 return move(Result); 3282} 3283 3284Sema::OwningExprResult Sema::BuildCXXDefaultArgExpr(SourceLocation CallLoc, 3285 FunctionDecl *FD, 3286 ParmVarDecl *Param) { 3287 if (Param->hasUnparsedDefaultArg()) { 3288 Diag (CallLoc, 3289 diag::err_use_of_default_argument_to_function_declared_later) << 3290 FD << cast<CXXRecordDecl>(FD->getDeclContext())->getDeclName(); 3291 Diag(UnparsedDefaultArgLocs[Param], 3292 diag::note_default_argument_declared_here); 3293 } else { 3294 if (Param->hasUninstantiatedDefaultArg()) { 3295 Expr *UninstExpr = Param->getUninstantiatedDefaultArg(); 3296 3297 // Instantiate the expression. 3298 MultiLevelTemplateArgumentList ArgList 3299 = getTemplateInstantiationArgs(FD, 0, /*RelativeToPrimary=*/true); 3300 3301 InstantiatingTemplate Inst(*this, CallLoc, Param, 3302 ArgList.getInnermost().getFlatArgumentList(), 3303 ArgList.getInnermost().flat_size()); 3304 3305 OwningExprResult Result = SubstExpr(UninstExpr, ArgList); 3306 if (Result.isInvalid()) 3307 return ExprError(); 3308 3309 // Check the expression as an initializer for the parameter. 3310 InitializedEntity Entity 3311 = InitializedEntity::InitializeParameter(Param); 3312 InitializationKind Kind 3313 = InitializationKind::CreateCopy(Param->getLocation(), 3314 /*FIXME:EqualLoc*/UninstExpr->getSourceRange().getBegin()); 3315 Expr *ResultE = Result.takeAs<Expr>(); 3316 3317 InitializationSequence InitSeq(*this, Entity, Kind, &ResultE, 1); 3318 Result = InitSeq.Perform(*this, Entity, Kind, 3319 MultiExprArg(*this, (void**)&ResultE, 1)); 3320 if (Result.isInvalid()) 3321 return ExprError(); 3322 3323 // Build the default argument expression. 3324 return Owned(CXXDefaultArgExpr::Create(Context, CallLoc, Param, 3325 Result.takeAs<Expr>())); 3326 } 3327 3328 // If the default expression creates temporaries, we need to 3329 // push them to the current stack of expression temporaries so they'll 3330 // be properly destroyed. 3331 // FIXME: We should really be rebuilding the default argument with new 3332 // bound temporaries; see the comment in PR5810. 3333 for (unsigned i = 0, e = Param->getNumDefaultArgTemporaries(); i != e; ++i) 3334 ExprTemporaries.push_back(Param->getDefaultArgTemporary(i)); 3335 } 3336 3337 // We already type-checked the argument, so we know it works. 3338 return Owned(CXXDefaultArgExpr::Create(Context, CallLoc, Param)); 3339} 3340 3341/// ConvertArgumentsForCall - Converts the arguments specified in 3342/// Args/NumArgs to the parameter types of the function FDecl with 3343/// function prototype Proto. Call is the call expression itself, and 3344/// Fn is the function expression. For a C++ member function, this 3345/// routine does not attempt to convert the object argument. Returns 3346/// true if the call is ill-formed. 3347bool 3348Sema::ConvertArgumentsForCall(CallExpr *Call, Expr *Fn, 3349 FunctionDecl *FDecl, 3350 const FunctionProtoType *Proto, 3351 Expr **Args, unsigned NumArgs, 3352 SourceLocation RParenLoc) { 3353 // C99 6.5.2.2p7 - the arguments are implicitly converted, as if by 3354 // assignment, to the types of the corresponding parameter, ... 3355 unsigned NumArgsInProto = Proto->getNumArgs(); 3356 bool Invalid = false; 3357 3358 // If too few arguments are available (and we don't have default 3359 // arguments for the remaining parameters), don't make the call. 3360 if (NumArgs < NumArgsInProto) { 3361 if (!FDecl || NumArgs < FDecl->getMinRequiredArguments()) 3362 return Diag(RParenLoc, diag::err_typecheck_call_too_few_args) 3363 << Fn->getType()->isBlockPointerType() 3364 << NumArgsInProto << NumArgs << Fn->getSourceRange(); 3365 Call->setNumArgs(Context, NumArgsInProto); 3366 } 3367 3368 // If too many are passed and not variadic, error on the extras and drop 3369 // them. 3370 if (NumArgs > NumArgsInProto) { 3371 if (!Proto->isVariadic()) { 3372 Diag(Args[NumArgsInProto]->getLocStart(), 3373 diag::err_typecheck_call_too_many_args) 3374 << Fn->getType()->isBlockPointerType() 3375 << NumArgsInProto << NumArgs << Fn->getSourceRange() 3376 << SourceRange(Args[NumArgsInProto]->getLocStart(), 3377 Args[NumArgs-1]->getLocEnd()); 3378 // This deletes the extra arguments. 3379 Call->setNumArgs(Context, NumArgsInProto); 3380 return true; 3381 } 3382 } 3383 llvm::SmallVector<Expr *, 8> AllArgs; 3384 VariadicCallType CallType = 3385 Proto->isVariadic() ? VariadicFunction : VariadicDoesNotApply; 3386 if (Fn->getType()->isBlockPointerType()) 3387 CallType = VariadicBlock; // Block 3388 else if (isa<MemberExpr>(Fn)) 3389 CallType = VariadicMethod; 3390 Invalid = GatherArgumentsForCall(Call->getSourceRange().getBegin(), FDecl, 3391 Proto, 0, Args, NumArgs, AllArgs, CallType); 3392 if (Invalid) 3393 return true; 3394 unsigned TotalNumArgs = AllArgs.size(); 3395 for (unsigned i = 0; i < TotalNumArgs; ++i) 3396 Call->setArg(i, AllArgs[i]); 3397 3398 return false; 3399} 3400 3401bool Sema::GatherArgumentsForCall(SourceLocation CallLoc, 3402 FunctionDecl *FDecl, 3403 const FunctionProtoType *Proto, 3404 unsigned FirstProtoArg, 3405 Expr **Args, unsigned NumArgs, 3406 llvm::SmallVector<Expr *, 8> &AllArgs, 3407 VariadicCallType CallType) { 3408 unsigned NumArgsInProto = Proto->getNumArgs(); 3409 unsigned NumArgsToCheck = NumArgs; 3410 bool Invalid = false; 3411 if (NumArgs != NumArgsInProto) 3412 // Use default arguments for missing arguments 3413 NumArgsToCheck = NumArgsInProto; 3414 unsigned ArgIx = 0; 3415 // Continue to check argument types (even if we have too few/many args). 3416 for (unsigned i = FirstProtoArg; i != NumArgsToCheck; i++) { 3417 QualType ProtoArgType = Proto->getArgType(i); 3418 3419 Expr *Arg; 3420 if (ArgIx < NumArgs) { 3421 Arg = Args[ArgIx++]; 3422 3423 if (RequireCompleteType(Arg->getSourceRange().getBegin(), 3424 ProtoArgType, 3425 PDiag(diag::err_call_incomplete_argument) 3426 << Arg->getSourceRange())) 3427 return true; 3428 3429 // Pass the argument 3430 ParmVarDecl *Param = 0; 3431 if (FDecl && i < FDecl->getNumParams()) 3432 Param = FDecl->getParamDecl(i); 3433 3434 3435 InitializedEntity Entity = 3436 Param? InitializedEntity::InitializeParameter(Param) 3437 : InitializedEntity::InitializeParameter(ProtoArgType); 3438 OwningExprResult ArgE = PerformCopyInitialization(Entity, 3439 SourceLocation(), 3440 Owned(Arg)); 3441 if (ArgE.isInvalid()) 3442 return true; 3443 3444 Arg = ArgE.takeAs<Expr>(); 3445 } else { 3446 ParmVarDecl *Param = FDecl->getParamDecl(i); 3447 3448 OwningExprResult ArgExpr = 3449 BuildCXXDefaultArgExpr(CallLoc, FDecl, Param); 3450 if (ArgExpr.isInvalid()) 3451 return true; 3452 3453 Arg = ArgExpr.takeAs<Expr>(); 3454 } 3455 AllArgs.push_back(Arg); 3456 } 3457 3458 // If this is a variadic call, handle args passed through "...". 3459 if (CallType != VariadicDoesNotApply) { 3460 // Promote the arguments (C99 6.5.2.2p7). 3461 for (unsigned i = ArgIx; i != NumArgs; ++i) { 3462 Expr *Arg = Args[i]; 3463 Invalid |= DefaultVariadicArgumentPromotion(Arg, CallType, FDecl); 3464 AllArgs.push_back(Arg); 3465 } 3466 } 3467 return Invalid; 3468} 3469 3470/// ActOnCallExpr - Handle a call to Fn with the specified array of arguments. 3471/// This provides the location of the left/right parens and a list of comma 3472/// locations. 3473Action::OwningExprResult 3474Sema::ActOnCallExpr(Scope *S, ExprArg fn, SourceLocation LParenLoc, 3475 MultiExprArg args, 3476 SourceLocation *CommaLocs, SourceLocation RParenLoc) { 3477 unsigned NumArgs = args.size(); 3478 3479 // Since this might be a postfix expression, get rid of ParenListExprs. 3480 fn = MaybeConvertParenListExprToParenExpr(S, move(fn)); 3481 3482 Expr *Fn = fn.takeAs<Expr>(); 3483 Expr **Args = reinterpret_cast<Expr**>(args.release()); 3484 assert(Fn && "no function call expression"); 3485 3486 if (getLangOptions().CPlusPlus) { 3487 // If this is a pseudo-destructor expression, build the call immediately. 3488 if (isa<CXXPseudoDestructorExpr>(Fn)) { 3489 if (NumArgs > 0) { 3490 // Pseudo-destructor calls should not have any arguments. 3491 Diag(Fn->getLocStart(), diag::err_pseudo_dtor_call_with_args) 3492 << FixItHint::CreateRemoval( 3493 SourceRange(Args[0]->getLocStart(), 3494 Args[NumArgs-1]->getLocEnd())); 3495 3496 for (unsigned I = 0; I != NumArgs; ++I) 3497 Args[I]->Destroy(Context); 3498 3499 NumArgs = 0; 3500 } 3501 3502 return Owned(new (Context) CallExpr(Context, Fn, 0, 0, Context.VoidTy, 3503 RParenLoc)); 3504 } 3505 3506 // Determine whether this is a dependent call inside a C++ template, 3507 // in which case we won't do any semantic analysis now. 3508 // FIXME: Will need to cache the results of name lookup (including ADL) in 3509 // Fn. 3510 bool Dependent = false; 3511 if (Fn->isTypeDependent()) 3512 Dependent = true; 3513 else if (Expr::hasAnyTypeDependentArguments(Args, NumArgs)) 3514 Dependent = true; 3515 3516 if (Dependent) 3517 return Owned(new (Context) CallExpr(Context, Fn, Args, NumArgs, 3518 Context.DependentTy, RParenLoc)); 3519 3520 // Determine whether this is a call to an object (C++ [over.call.object]). 3521 if (Fn->getType()->isRecordType()) 3522 return Owned(BuildCallToObjectOfClassType(S, Fn, LParenLoc, Args, NumArgs, 3523 CommaLocs, RParenLoc)); 3524 3525 Expr *NakedFn = Fn->IgnoreParens(); 3526 3527 // Determine whether this is a call to an unresolved member function. 3528 if (UnresolvedMemberExpr *MemE = dyn_cast<UnresolvedMemberExpr>(NakedFn)) { 3529 // If lookup was unresolved but not dependent (i.e. didn't find 3530 // an unresolved using declaration), it has to be an overloaded 3531 // function set, which means it must contain either multiple 3532 // declarations (all methods or method templates) or a single 3533 // method template. 3534 assert((MemE->getNumDecls() > 1) || 3535 isa<FunctionTemplateDecl>( 3536 (*MemE->decls_begin())->getUnderlyingDecl())); 3537 (void)MemE; 3538 3539 return BuildCallToMemberFunction(S, Fn, LParenLoc, Args, NumArgs, 3540 CommaLocs, RParenLoc); 3541 } 3542 3543 // Determine whether this is a call to a member function. 3544 if (MemberExpr *MemExpr = dyn_cast<MemberExpr>(NakedFn)) { 3545 NamedDecl *MemDecl = MemExpr->getMemberDecl(); 3546 if (isa<CXXMethodDecl>(MemDecl)) 3547 return BuildCallToMemberFunction(S, Fn, LParenLoc, Args, NumArgs, 3548 CommaLocs, RParenLoc); 3549 } 3550 3551 // Determine whether this is a call to a pointer-to-member function. 3552 if (BinaryOperator *BO = dyn_cast<BinaryOperator>(NakedFn)) { 3553 if (BO->getOpcode() == BinaryOperator::PtrMemD || 3554 BO->getOpcode() == BinaryOperator::PtrMemI) { 3555 if (const FunctionProtoType *FPT 3556 = BO->getType()->getAs<FunctionProtoType>()) { 3557 QualType ResultTy = FPT->getResultType().getNonReferenceType(); 3558 3559 ExprOwningPtr<CXXMemberCallExpr> 3560 TheCall(this, new (Context) CXXMemberCallExpr(Context, BO, Args, 3561 NumArgs, ResultTy, 3562 RParenLoc)); 3563 3564 if (CheckCallReturnType(FPT->getResultType(), 3565 BO->getRHS()->getSourceRange().getBegin(), 3566 TheCall.get(), 0)) 3567 return ExprError(); 3568 3569 if (ConvertArgumentsForCall(&*TheCall, BO, 0, FPT, Args, NumArgs, 3570 RParenLoc)) 3571 return ExprError(); 3572 3573 return Owned(MaybeBindToTemporary(TheCall.release()).release()); 3574 } 3575 return ExprError(Diag(Fn->getLocStart(), 3576 diag::err_typecheck_call_not_function) 3577 << Fn->getType() << Fn->getSourceRange()); 3578 } 3579 } 3580 } 3581 3582 // If we're directly calling a function, get the appropriate declaration. 3583 // Also, in C++, keep track of whether we should perform argument-dependent 3584 // lookup and whether there were any explicitly-specified template arguments. 3585 3586 Expr *NakedFn = Fn->IgnoreParens(); 3587 if (isa<UnresolvedLookupExpr>(NakedFn)) { 3588 UnresolvedLookupExpr *ULE = cast<UnresolvedLookupExpr>(NakedFn); 3589 return BuildOverloadedCallExpr(S, Fn, ULE, LParenLoc, Args, NumArgs, 3590 CommaLocs, RParenLoc); 3591 } 3592 3593 NamedDecl *NDecl = 0; 3594 if (isa<DeclRefExpr>(NakedFn)) 3595 NDecl = cast<DeclRefExpr>(NakedFn)->getDecl(); 3596 3597 return BuildResolvedCallExpr(Fn, NDecl, LParenLoc, Args, NumArgs, RParenLoc); 3598} 3599 3600/// BuildResolvedCallExpr - Build a call to a resolved expression, 3601/// i.e. an expression not of \p OverloadTy. The expression should 3602/// unary-convert to an expression of function-pointer or 3603/// block-pointer type. 3604/// 3605/// \param NDecl the declaration being called, if available 3606Sema::OwningExprResult 3607Sema::BuildResolvedCallExpr(Expr *Fn, NamedDecl *NDecl, 3608 SourceLocation LParenLoc, 3609 Expr **Args, unsigned NumArgs, 3610 SourceLocation RParenLoc) { 3611 FunctionDecl *FDecl = dyn_cast_or_null<FunctionDecl>(NDecl); 3612 3613 // Promote the function operand. 3614 UsualUnaryConversions(Fn); 3615 3616 // Make the call expr early, before semantic checks. This guarantees cleanup 3617 // of arguments and function on error. 3618 ExprOwningPtr<CallExpr> TheCall(this, new (Context) CallExpr(Context, Fn, 3619 Args, NumArgs, 3620 Context.BoolTy, 3621 RParenLoc)); 3622 3623 const FunctionType *FuncT; 3624 if (!Fn->getType()->isBlockPointerType()) { 3625 // C99 6.5.2.2p1 - "The expression that denotes the called function shall 3626 // have type pointer to function". 3627 const PointerType *PT = Fn->getType()->getAs<PointerType>(); 3628 if (PT == 0) 3629 return ExprError(Diag(LParenLoc, diag::err_typecheck_call_not_function) 3630 << Fn->getType() << Fn->getSourceRange()); 3631 FuncT = PT->getPointeeType()->getAs<FunctionType>(); 3632 } else { // This is a block call. 3633 FuncT = Fn->getType()->getAs<BlockPointerType>()->getPointeeType()-> 3634 getAs<FunctionType>(); 3635 } 3636 if (FuncT == 0) 3637 return ExprError(Diag(LParenLoc, diag::err_typecheck_call_not_function) 3638 << Fn->getType() << Fn->getSourceRange()); 3639 3640 // Check for a valid return type 3641 if (CheckCallReturnType(FuncT->getResultType(), 3642 Fn->getSourceRange().getBegin(), TheCall.get(), 3643 FDecl)) 3644 return ExprError(); 3645 3646 // We know the result type of the call, set it. 3647 TheCall->setType(FuncT->getResultType().getNonReferenceType()); 3648 3649 if (const FunctionProtoType *Proto = dyn_cast<FunctionProtoType>(FuncT)) { 3650 if (ConvertArgumentsForCall(&*TheCall, Fn, FDecl, Proto, Args, NumArgs, 3651 RParenLoc)) 3652 return ExprError(); 3653 } else { 3654 assert(isa<FunctionNoProtoType>(FuncT) && "Unknown FunctionType!"); 3655 3656 if (FDecl) { 3657 // Check if we have too few/too many template arguments, based 3658 // on our knowledge of the function definition. 3659 const FunctionDecl *Def = 0; 3660 if (FDecl->getBody(Def) && NumArgs != Def->param_size()) { 3661 const FunctionProtoType *Proto = 3662 Def->getType()->getAs<FunctionProtoType>(); 3663 if (!Proto || !(Proto->isVariadic() && NumArgs >= Def->param_size())) { 3664 Diag(RParenLoc, diag::warn_call_wrong_number_of_arguments) 3665 << (NumArgs > Def->param_size()) << FDecl << Fn->getSourceRange(); 3666 } 3667 } 3668 } 3669 3670 // Promote the arguments (C99 6.5.2.2p6). 3671 for (unsigned i = 0; i != NumArgs; i++) { 3672 Expr *Arg = Args[i]; 3673 DefaultArgumentPromotion(Arg); 3674 if (RequireCompleteType(Arg->getSourceRange().getBegin(), 3675 Arg->getType(), 3676 PDiag(diag::err_call_incomplete_argument) 3677 << Arg->getSourceRange())) 3678 return ExprError(); 3679 TheCall->setArg(i, Arg); 3680 } 3681 } 3682 3683 if (CXXMethodDecl *Method = dyn_cast_or_null<CXXMethodDecl>(FDecl)) 3684 if (!Method->isStatic()) 3685 return ExprError(Diag(LParenLoc, diag::err_member_call_without_object) 3686 << Fn->getSourceRange()); 3687 3688 // Check for sentinels 3689 if (NDecl) 3690 DiagnoseSentinelCalls(NDecl, LParenLoc, Args, NumArgs); 3691 3692 // Do special checking on direct calls to functions. 3693 if (FDecl) { 3694 if (CheckFunctionCall(FDecl, TheCall.get())) 3695 return ExprError(); 3696 3697 if (unsigned BuiltinID = FDecl->getBuiltinID()) 3698 return CheckBuiltinFunctionCall(BuiltinID, TheCall.take()); 3699 } else if (NDecl) { 3700 if (CheckBlockCall(NDecl, TheCall.get())) 3701 return ExprError(); 3702 } 3703 3704 return MaybeBindToTemporary(TheCall.take()); 3705} 3706 3707Action::OwningExprResult 3708Sema::ActOnCompoundLiteral(SourceLocation LParenLoc, TypeTy *Ty, 3709 SourceLocation RParenLoc, ExprArg InitExpr) { 3710 assert((Ty != 0) && "ActOnCompoundLiteral(): missing type"); 3711 // FIXME: put back this assert when initializers are worked out. 3712 //assert((InitExpr != 0) && "ActOnCompoundLiteral(): missing expression"); 3713 3714 TypeSourceInfo *TInfo; 3715 QualType literalType = GetTypeFromParser(Ty, &TInfo); 3716 if (!TInfo) 3717 TInfo = Context.getTrivialTypeSourceInfo(literalType); 3718 3719 return BuildCompoundLiteralExpr(LParenLoc, TInfo, RParenLoc, move(InitExpr)); 3720} 3721 3722Action::OwningExprResult 3723Sema::BuildCompoundLiteralExpr(SourceLocation LParenLoc, TypeSourceInfo *TInfo, 3724 SourceLocation RParenLoc, ExprArg InitExpr) { 3725 QualType literalType = TInfo->getType(); 3726 Expr *literalExpr = static_cast<Expr*>(InitExpr.get()); 3727 3728 if (literalType->isArrayType()) { 3729 if (literalType->isVariableArrayType()) 3730 return ExprError(Diag(LParenLoc, diag::err_variable_object_no_init) 3731 << SourceRange(LParenLoc, literalExpr->getSourceRange().getEnd())); 3732 } else if (!literalType->isDependentType() && 3733 RequireCompleteType(LParenLoc, literalType, 3734 PDiag(diag::err_typecheck_decl_incomplete_type) 3735 << SourceRange(LParenLoc, 3736 literalExpr->getSourceRange().getEnd()))) 3737 return ExprError(); 3738 3739 InitializedEntity Entity 3740 = InitializedEntity::InitializeTemporary(literalType); 3741 InitializationKind Kind 3742 = InitializationKind::CreateCast(SourceRange(LParenLoc, RParenLoc), 3743 /*IsCStyleCast=*/true); 3744 InitializationSequence InitSeq(*this, Entity, Kind, &literalExpr, 1); 3745 OwningExprResult Result = InitSeq.Perform(*this, Entity, Kind, 3746 MultiExprArg(*this, (void**)&literalExpr, 1), 3747 &literalType); 3748 if (Result.isInvalid()) 3749 return ExprError(); 3750 InitExpr.release(); 3751 literalExpr = static_cast<Expr*>(Result.get()); 3752 3753 bool isFileScope = getCurFunctionOrMethodDecl() == 0; 3754 if (isFileScope) { // 6.5.2.5p3 3755 if (CheckForConstantInitializer(literalExpr, literalType)) 3756 return ExprError(); 3757 } 3758 3759 Result.release(); 3760 3761 return Owned(new (Context) CompoundLiteralExpr(LParenLoc, TInfo, literalType, 3762 literalExpr, isFileScope)); 3763} 3764 3765Action::OwningExprResult 3766Sema::ActOnInitList(SourceLocation LBraceLoc, MultiExprArg initlist, 3767 SourceLocation RBraceLoc) { 3768 unsigned NumInit = initlist.size(); 3769 Expr **InitList = reinterpret_cast<Expr**>(initlist.release()); 3770 3771 // Semantic analysis for initializers is done by ActOnDeclarator() and 3772 // CheckInitializer() - it requires knowledge of the object being intialized. 3773 3774 InitListExpr *E = new (Context) InitListExpr(Context, LBraceLoc, InitList, 3775 NumInit, RBraceLoc); 3776 E->setType(Context.VoidTy); // FIXME: just a place holder for now. 3777 return Owned(E); 3778} 3779 3780static CastExpr::CastKind getScalarCastKind(ASTContext &Context, 3781 QualType SrcTy, QualType DestTy) { 3782 if (Context.hasSameUnqualifiedType(SrcTy, DestTy)) 3783 return CastExpr::CK_NoOp; 3784 3785 if (SrcTy->hasPointerRepresentation()) { 3786 if (DestTy->hasPointerRepresentation()) 3787 return DestTy->isObjCObjectPointerType() ? 3788 CastExpr::CK_AnyPointerToObjCPointerCast : 3789 CastExpr::CK_BitCast; 3790 if (DestTy->isIntegerType()) 3791 return CastExpr::CK_PointerToIntegral; 3792 } 3793 3794 if (SrcTy->isIntegerType()) { 3795 if (DestTy->isIntegerType()) 3796 return CastExpr::CK_IntegralCast; 3797 if (DestTy->hasPointerRepresentation()) 3798 return CastExpr::CK_IntegralToPointer; 3799 if (DestTy->isRealFloatingType()) 3800 return CastExpr::CK_IntegralToFloating; 3801 } 3802 3803 if (SrcTy->isRealFloatingType()) { 3804 if (DestTy->isRealFloatingType()) 3805 return CastExpr::CK_FloatingCast; 3806 if (DestTy->isIntegerType()) 3807 return CastExpr::CK_FloatingToIntegral; 3808 } 3809 3810 // FIXME: Assert here. 3811 // assert(false && "Unhandled cast combination!"); 3812 return CastExpr::CK_Unknown; 3813} 3814 3815/// CheckCastTypes - Check type constraints for casting between types. 3816bool Sema::CheckCastTypes(SourceRange TyR, QualType castType, Expr *&castExpr, 3817 CastExpr::CastKind& Kind, 3818 CXXBaseSpecifierArray &BasePath, 3819 bool FunctionalStyle) { 3820 if (getLangOptions().CPlusPlus) 3821 return CXXCheckCStyleCast(TyR, castType, castExpr, Kind, BasePath, 3822 FunctionalStyle); 3823 3824 DefaultFunctionArrayLvalueConversion(castExpr); 3825 3826 // C99 6.5.4p2: the cast type needs to be void or scalar and the expression 3827 // type needs to be scalar. 3828 if (castType->isVoidType()) { 3829 // Cast to void allows any expr type. 3830 Kind = CastExpr::CK_ToVoid; 3831 return false; 3832 } 3833 3834 if (!castType->isScalarType() && !castType->isVectorType()) { 3835 if (Context.hasSameUnqualifiedType(castType, castExpr->getType()) && 3836 (castType->isStructureType() || castType->isUnionType())) { 3837 // GCC struct/union extension: allow cast to self. 3838 // FIXME: Check that the cast destination type is complete. 3839 Diag(TyR.getBegin(), diag::ext_typecheck_cast_nonscalar) 3840 << castType << castExpr->getSourceRange(); 3841 Kind = CastExpr::CK_NoOp; 3842 return false; 3843 } 3844 3845 if (castType->isUnionType()) { 3846 // GCC cast to union extension 3847 RecordDecl *RD = castType->getAs<RecordType>()->getDecl(); 3848 RecordDecl::field_iterator Field, FieldEnd; 3849 for (Field = RD->field_begin(), FieldEnd = RD->field_end(); 3850 Field != FieldEnd; ++Field) { 3851 if (Context.hasSameUnqualifiedType(Field->getType(), 3852 castExpr->getType())) { 3853 Diag(TyR.getBegin(), diag::ext_typecheck_cast_to_union) 3854 << castExpr->getSourceRange(); 3855 break; 3856 } 3857 } 3858 if (Field == FieldEnd) 3859 return Diag(TyR.getBegin(), diag::err_typecheck_cast_to_union_no_type) 3860 << castExpr->getType() << castExpr->getSourceRange(); 3861 Kind = CastExpr::CK_ToUnion; 3862 return false; 3863 } 3864 3865 // Reject any other conversions to non-scalar types. 3866 return Diag(TyR.getBegin(), diag::err_typecheck_cond_expect_scalar) 3867 << castType << castExpr->getSourceRange(); 3868 } 3869 3870 if (!castExpr->getType()->isScalarType() && 3871 !castExpr->getType()->isVectorType()) { 3872 return Diag(castExpr->getLocStart(), 3873 diag::err_typecheck_expect_scalar_operand) 3874 << castExpr->getType() << castExpr->getSourceRange(); 3875 } 3876 3877 if (castType->isExtVectorType()) 3878 return CheckExtVectorCast(TyR, castType, castExpr, Kind); 3879 3880 if (castType->isVectorType()) 3881 return CheckVectorCast(TyR, castType, castExpr->getType(), Kind); 3882 if (castExpr->getType()->isVectorType()) 3883 return CheckVectorCast(TyR, castExpr->getType(), castType, Kind); 3884 3885 if (isa<ObjCSelectorExpr>(castExpr)) 3886 return Diag(castExpr->getLocStart(), diag::err_cast_selector_expr); 3887 3888 if (!castType->isArithmeticType()) { 3889 QualType castExprType = castExpr->getType(); 3890 if (!castExprType->isIntegralType() && castExprType->isArithmeticType()) 3891 return Diag(castExpr->getLocStart(), 3892 diag::err_cast_pointer_from_non_pointer_int) 3893 << castExprType << castExpr->getSourceRange(); 3894 } else if (!castExpr->getType()->isArithmeticType()) { 3895 if (!castType->isIntegralType() && castType->isArithmeticType()) 3896 return Diag(castExpr->getLocStart(), 3897 diag::err_cast_pointer_to_non_pointer_int) 3898 << castType << castExpr->getSourceRange(); 3899 } 3900 3901 Kind = getScalarCastKind(Context, castExpr->getType(), castType); 3902 return false; 3903} 3904 3905bool Sema::CheckVectorCast(SourceRange R, QualType VectorTy, QualType Ty, 3906 CastExpr::CastKind &Kind) { 3907 assert(VectorTy->isVectorType() && "Not a vector type!"); 3908 3909 if (Ty->isVectorType() || Ty->isIntegerType()) { 3910 if (Context.getTypeSize(VectorTy) != Context.getTypeSize(Ty)) 3911 return Diag(R.getBegin(), 3912 Ty->isVectorType() ? 3913 diag::err_invalid_conversion_between_vectors : 3914 diag::err_invalid_conversion_between_vector_and_integer) 3915 << VectorTy << Ty << R; 3916 } else 3917 return Diag(R.getBegin(), 3918 diag::err_invalid_conversion_between_vector_and_scalar) 3919 << VectorTy << Ty << R; 3920 3921 Kind = CastExpr::CK_BitCast; 3922 return false; 3923} 3924 3925bool Sema::CheckExtVectorCast(SourceRange R, QualType DestTy, Expr *&CastExpr, 3926 CastExpr::CastKind &Kind) { 3927 assert(DestTy->isExtVectorType() && "Not an extended vector type!"); 3928 3929 QualType SrcTy = CastExpr->getType(); 3930 3931 // If SrcTy is a VectorType, the total size must match to explicitly cast to 3932 // an ExtVectorType. 3933 if (SrcTy->isVectorType()) { 3934 if (Context.getTypeSize(DestTy) != Context.getTypeSize(SrcTy)) 3935 return Diag(R.getBegin(),diag::err_invalid_conversion_between_ext_vectors) 3936 << DestTy << SrcTy << R; 3937 Kind = CastExpr::CK_BitCast; 3938 return false; 3939 } 3940 3941 // All non-pointer scalars can be cast to ExtVector type. The appropriate 3942 // conversion will take place first from scalar to elt type, and then 3943 // splat from elt type to vector. 3944 if (SrcTy->isPointerType()) 3945 return Diag(R.getBegin(), 3946 diag::err_invalid_conversion_between_vector_and_scalar) 3947 << DestTy << SrcTy << R; 3948 3949 QualType DestElemTy = DestTy->getAs<ExtVectorType>()->getElementType(); 3950 ImpCastExprToType(CastExpr, DestElemTy, 3951 getScalarCastKind(Context, SrcTy, DestElemTy)); 3952 3953 Kind = CastExpr::CK_VectorSplat; 3954 return false; 3955} 3956 3957Action::OwningExprResult 3958Sema::ActOnCastExpr(Scope *S, SourceLocation LParenLoc, TypeTy *Ty, 3959 SourceLocation RParenLoc, ExprArg Op) { 3960 assert((Ty != 0) && (Op.get() != 0) && 3961 "ActOnCastExpr(): missing type or expr"); 3962 3963 TypeSourceInfo *castTInfo; 3964 QualType castType = GetTypeFromParser(Ty, &castTInfo); 3965 if (!castTInfo) 3966 castTInfo = Context.getTrivialTypeSourceInfo(castType); 3967 3968 // If the Expr being casted is a ParenListExpr, handle it specially. 3969 Expr *castExpr = (Expr *)Op.get(); 3970 if (isa<ParenListExpr>(castExpr)) 3971 return ActOnCastOfParenListExpr(S, LParenLoc, RParenLoc, move(Op), 3972 castTInfo); 3973 3974 return BuildCStyleCastExpr(LParenLoc, castTInfo, RParenLoc, move(Op)); 3975} 3976 3977Action::OwningExprResult 3978Sema::BuildCStyleCastExpr(SourceLocation LParenLoc, TypeSourceInfo *Ty, 3979 SourceLocation RParenLoc, ExprArg Op) { 3980 Expr *castExpr = static_cast<Expr*>(Op.get()); 3981 3982 CastExpr::CastKind Kind = CastExpr::CK_Unknown; 3983 CXXBaseSpecifierArray BasePath; 3984 if (CheckCastTypes(SourceRange(LParenLoc, RParenLoc), Ty->getType(), castExpr, 3985 Kind, BasePath)) 3986 return ExprError(); 3987 3988 Op.release(); 3989 return Owned(new (Context) CStyleCastExpr(Ty->getType().getNonReferenceType(), 3990 Kind, castExpr, BasePath, Ty, 3991 LParenLoc, RParenLoc)); 3992} 3993 3994/// This is not an AltiVec-style cast, so turn the ParenListExpr into a sequence 3995/// of comma binary operators. 3996Action::OwningExprResult 3997Sema::MaybeConvertParenListExprToParenExpr(Scope *S, ExprArg EA) { 3998 Expr *expr = EA.takeAs<Expr>(); 3999 ParenListExpr *E = dyn_cast<ParenListExpr>(expr); 4000 if (!E) 4001 return Owned(expr); 4002 4003 OwningExprResult Result(*this, E->getExpr(0)); 4004 4005 for (unsigned i = 1, e = E->getNumExprs(); i != e && !Result.isInvalid(); ++i) 4006 Result = ActOnBinOp(S, E->getExprLoc(), tok::comma, move(Result), 4007 Owned(E->getExpr(i))); 4008 4009 return ActOnParenExpr(E->getLParenLoc(), E->getRParenLoc(), move(Result)); 4010} 4011 4012Action::OwningExprResult 4013Sema::ActOnCastOfParenListExpr(Scope *S, SourceLocation LParenLoc, 4014 SourceLocation RParenLoc, ExprArg Op, 4015 TypeSourceInfo *TInfo) { 4016 ParenListExpr *PE = (ParenListExpr *)Op.get(); 4017 QualType Ty = TInfo->getType(); 4018 4019 // If this is an altivec initializer, '(' type ')' '(' init, ..., init ')' 4020 // then handle it as such. 4021 if (getLangOptions().AltiVec && Ty->isVectorType()) { 4022 if (PE->getNumExprs() == 0) { 4023 Diag(PE->getExprLoc(), diag::err_altivec_empty_initializer); 4024 return ExprError(); 4025 } 4026 4027 llvm::SmallVector<Expr *, 8> initExprs; 4028 for (unsigned i = 0, e = PE->getNumExprs(); i != e; ++i) 4029 initExprs.push_back(PE->getExpr(i)); 4030 4031 // FIXME: This means that pretty-printing the final AST will produce curly 4032 // braces instead of the original commas. 4033 Op.release(); 4034 InitListExpr *E = new (Context) InitListExpr(Context, LParenLoc, 4035 &initExprs[0], 4036 initExprs.size(), RParenLoc); 4037 E->setType(Ty); 4038 return BuildCompoundLiteralExpr(LParenLoc, TInfo, RParenLoc, Owned(E)); 4039 } else { 4040 // This is not an AltiVec-style cast, so turn the ParenListExpr into a 4041 // sequence of BinOp comma operators. 4042 Op = MaybeConvertParenListExprToParenExpr(S, move(Op)); 4043 return BuildCStyleCastExpr(LParenLoc, TInfo, RParenLoc, move(Op)); 4044 } 4045} 4046 4047Action::OwningExprResult Sema::ActOnParenOrParenListExpr(SourceLocation L, 4048 SourceLocation R, 4049 MultiExprArg Val, 4050 TypeTy *TypeOfCast) { 4051 unsigned nexprs = Val.size(); 4052 Expr **exprs = reinterpret_cast<Expr**>(Val.release()); 4053 assert((exprs != 0) && "ActOnParenOrParenListExpr() missing expr list"); 4054 Expr *expr; 4055 if (nexprs == 1 && TypeOfCast && !TypeIsVectorType(TypeOfCast)) 4056 expr = new (Context) ParenExpr(L, R, exprs[0]); 4057 else 4058 expr = new (Context) ParenListExpr(Context, L, exprs, nexprs, R); 4059 return Owned(expr); 4060} 4061 4062/// Note that lhs is not null here, even if this is the gnu "x ?: y" extension. 4063/// In that case, lhs = cond. 4064/// C99 6.5.15 4065QualType Sema::CheckConditionalOperands(Expr *&Cond, Expr *&LHS, Expr *&RHS, 4066 SourceLocation QuestionLoc) { 4067 // C++ is sufficiently different to merit its own checker. 4068 if (getLangOptions().CPlusPlus) 4069 return CXXCheckConditionalOperands(Cond, LHS, RHS, QuestionLoc); 4070 4071 UsualUnaryConversions(Cond); 4072 UsualUnaryConversions(LHS); 4073 UsualUnaryConversions(RHS); 4074 QualType CondTy = Cond->getType(); 4075 QualType LHSTy = LHS->getType(); 4076 QualType RHSTy = RHS->getType(); 4077 4078 // first, check the condition. 4079 if (!CondTy->isScalarType()) { // C99 6.5.15p2 4080 Diag(Cond->getLocStart(), diag::err_typecheck_cond_expect_scalar) 4081 << CondTy; 4082 return QualType(); 4083 } 4084 4085 // Now check the two expressions. 4086 if (LHSTy->isVectorType() || RHSTy->isVectorType()) 4087 return CheckVectorOperands(QuestionLoc, LHS, RHS); 4088 4089 // If both operands have arithmetic type, do the usual arithmetic conversions 4090 // to find a common type: C99 6.5.15p3,5. 4091 if (LHSTy->isArithmeticType() && RHSTy->isArithmeticType()) { 4092 UsualArithmeticConversions(LHS, RHS); 4093 return LHS->getType(); 4094 } 4095 4096 // If both operands are the same structure or union type, the result is that 4097 // type. 4098 if (const RecordType *LHSRT = LHSTy->getAs<RecordType>()) { // C99 6.5.15p3 4099 if (const RecordType *RHSRT = RHSTy->getAs<RecordType>()) 4100 if (LHSRT->getDecl() == RHSRT->getDecl()) 4101 // "If both the operands have structure or union type, the result has 4102 // that type." This implies that CV qualifiers are dropped. 4103 return LHSTy.getUnqualifiedType(); 4104 // FIXME: Type of conditional expression must be complete in C mode. 4105 } 4106 4107 // C99 6.5.15p5: "If both operands have void type, the result has void type." 4108 // The following || allows only one side to be void (a GCC-ism). 4109 if (LHSTy->isVoidType() || RHSTy->isVoidType()) { 4110 if (!LHSTy->isVoidType()) 4111 Diag(RHS->getLocStart(), diag::ext_typecheck_cond_one_void) 4112 << RHS->getSourceRange(); 4113 if (!RHSTy->isVoidType()) 4114 Diag(LHS->getLocStart(), diag::ext_typecheck_cond_one_void) 4115 << LHS->getSourceRange(); 4116 ImpCastExprToType(LHS, Context.VoidTy, CastExpr::CK_ToVoid); 4117 ImpCastExprToType(RHS, Context.VoidTy, CastExpr::CK_ToVoid); 4118 return Context.VoidTy; 4119 } 4120 // C99 6.5.15p6 - "if one operand is a null pointer constant, the result has 4121 // the type of the other operand." 4122 if ((LHSTy->isAnyPointerType() || LHSTy->isBlockPointerType()) && 4123 RHS->isNullPointerConstant(Context, Expr::NPC_ValueDependentIsNull)) { 4124 // promote the null to a pointer. 4125 ImpCastExprToType(RHS, LHSTy, CastExpr::CK_Unknown); 4126 return LHSTy; 4127 } 4128 if ((RHSTy->isAnyPointerType() || RHSTy->isBlockPointerType()) && 4129 LHS->isNullPointerConstant(Context, Expr::NPC_ValueDependentIsNull)) { 4130 ImpCastExprToType(LHS, RHSTy, CastExpr::CK_Unknown); 4131 return RHSTy; 4132 } 4133 4134 // All objective-c pointer type analysis is done here. 4135 QualType compositeType = FindCompositeObjCPointerType(LHS, RHS, 4136 QuestionLoc); 4137 if (!compositeType.isNull()) 4138 return compositeType; 4139 4140 4141 // Handle block pointer types. 4142 if (LHSTy->isBlockPointerType() || RHSTy->isBlockPointerType()) { 4143 if (!LHSTy->isBlockPointerType() || !RHSTy->isBlockPointerType()) { 4144 if (LHSTy->isVoidPointerType() || RHSTy->isVoidPointerType()) { 4145 QualType destType = Context.getPointerType(Context.VoidTy); 4146 ImpCastExprToType(LHS, destType, CastExpr::CK_BitCast); 4147 ImpCastExprToType(RHS, destType, CastExpr::CK_BitCast); 4148 return destType; 4149 } 4150 Diag(QuestionLoc, diag::err_typecheck_cond_incompatible_operands) 4151 << LHSTy << RHSTy << LHS->getSourceRange() << RHS->getSourceRange(); 4152 return QualType(); 4153 } 4154 // We have 2 block pointer types. 4155 if (Context.getCanonicalType(LHSTy) == Context.getCanonicalType(RHSTy)) { 4156 // Two identical block pointer types are always compatible. 4157 return LHSTy; 4158 } 4159 // The block pointer types aren't identical, continue checking. 4160 QualType lhptee = LHSTy->getAs<BlockPointerType>()->getPointeeType(); 4161 QualType rhptee = RHSTy->getAs<BlockPointerType>()->getPointeeType(); 4162 4163 if (!Context.typesAreCompatible(lhptee.getUnqualifiedType(), 4164 rhptee.getUnqualifiedType())) { 4165 Diag(QuestionLoc, diag::warn_typecheck_cond_incompatible_pointers) 4166 << LHSTy << RHSTy << LHS->getSourceRange() << RHS->getSourceRange(); 4167 // In this situation, we assume void* type. No especially good 4168 // reason, but this is what gcc does, and we do have to pick 4169 // to get a consistent AST. 4170 QualType incompatTy = Context.getPointerType(Context.VoidTy); 4171 ImpCastExprToType(LHS, incompatTy, CastExpr::CK_BitCast); 4172 ImpCastExprToType(RHS, incompatTy, CastExpr::CK_BitCast); 4173 return incompatTy; 4174 } 4175 // The block pointer types are compatible. 4176 ImpCastExprToType(LHS, LHSTy, CastExpr::CK_BitCast); 4177 ImpCastExprToType(RHS, LHSTy, CastExpr::CK_BitCast); 4178 return LHSTy; 4179 } 4180 4181 // Check constraints for C object pointers types (C99 6.5.15p3,6). 4182 if (LHSTy->isPointerType() && RHSTy->isPointerType()) { 4183 // get the "pointed to" types 4184 QualType lhptee = LHSTy->getAs<PointerType>()->getPointeeType(); 4185 QualType rhptee = RHSTy->getAs<PointerType>()->getPointeeType(); 4186 4187 // ignore qualifiers on void (C99 6.5.15p3, clause 6) 4188 if (lhptee->isVoidType() && rhptee->isIncompleteOrObjectType()) { 4189 // Figure out necessary qualifiers (C99 6.5.15p6) 4190 QualType destPointee 4191 = Context.getQualifiedType(lhptee, rhptee.getQualifiers()); 4192 QualType destType = Context.getPointerType(destPointee); 4193 // Add qualifiers if necessary. 4194 ImpCastExprToType(LHS, destType, CastExpr::CK_NoOp); 4195 // Promote to void*. 4196 ImpCastExprToType(RHS, destType, CastExpr::CK_BitCast); 4197 return destType; 4198 } 4199 if (rhptee->isVoidType() && lhptee->isIncompleteOrObjectType()) { 4200 QualType destPointee 4201 = Context.getQualifiedType(rhptee, lhptee.getQualifiers()); 4202 QualType destType = Context.getPointerType(destPointee); 4203 // Add qualifiers if necessary. 4204 ImpCastExprToType(RHS, destType, CastExpr::CK_NoOp); 4205 // Promote to void*. 4206 ImpCastExprToType(LHS, destType, CastExpr::CK_BitCast); 4207 return destType; 4208 } 4209 4210 if (Context.getCanonicalType(LHSTy) == Context.getCanonicalType(RHSTy)) { 4211 // Two identical pointer types are always compatible. 4212 return LHSTy; 4213 } 4214 if (!Context.typesAreCompatible(lhptee.getUnqualifiedType(), 4215 rhptee.getUnqualifiedType())) { 4216 Diag(QuestionLoc, diag::warn_typecheck_cond_incompatible_pointers) 4217 << LHSTy << RHSTy << LHS->getSourceRange() << RHS->getSourceRange(); 4218 // In this situation, we assume void* type. No especially good 4219 // reason, but this is what gcc does, and we do have to pick 4220 // to get a consistent AST. 4221 QualType incompatTy = Context.getPointerType(Context.VoidTy); 4222 ImpCastExprToType(LHS, incompatTy, CastExpr::CK_BitCast); 4223 ImpCastExprToType(RHS, incompatTy, CastExpr::CK_BitCast); 4224 return incompatTy; 4225 } 4226 // The pointer types are compatible. 4227 // C99 6.5.15p6: If both operands are pointers to compatible types *or* to 4228 // differently qualified versions of compatible types, the result type is 4229 // a pointer to an appropriately qualified version of the *composite* 4230 // type. 4231 // FIXME: Need to calculate the composite type. 4232 // FIXME: Need to add qualifiers 4233 ImpCastExprToType(LHS, LHSTy, CastExpr::CK_BitCast); 4234 ImpCastExprToType(RHS, LHSTy, CastExpr::CK_BitCast); 4235 return LHSTy; 4236 } 4237 4238 // GCC compatibility: soften pointer/integer mismatch. 4239 if (RHSTy->isPointerType() && LHSTy->isIntegerType()) { 4240 Diag(QuestionLoc, diag::warn_typecheck_cond_pointer_integer_mismatch) 4241 << LHSTy << RHSTy << LHS->getSourceRange() << RHS->getSourceRange(); 4242 ImpCastExprToType(LHS, RHSTy, CastExpr::CK_IntegralToPointer); 4243 return RHSTy; 4244 } 4245 if (LHSTy->isPointerType() && RHSTy->isIntegerType()) { 4246 Diag(QuestionLoc, diag::warn_typecheck_cond_pointer_integer_mismatch) 4247 << LHSTy << RHSTy << LHS->getSourceRange() << RHS->getSourceRange(); 4248 ImpCastExprToType(RHS, LHSTy, CastExpr::CK_IntegralToPointer); 4249 return LHSTy; 4250 } 4251 4252 // Otherwise, the operands are not compatible. 4253 Diag(QuestionLoc, diag::err_typecheck_cond_incompatible_operands) 4254 << LHSTy << RHSTy << LHS->getSourceRange() << RHS->getSourceRange(); 4255 return QualType(); 4256} 4257 4258/// FindCompositeObjCPointerType - Helper method to find composite type of 4259/// two objective-c pointer types of the two input expressions. 4260QualType Sema::FindCompositeObjCPointerType(Expr *&LHS, Expr *&RHS, 4261 SourceLocation QuestionLoc) { 4262 QualType LHSTy = LHS->getType(); 4263 QualType RHSTy = RHS->getType(); 4264 4265 // Handle things like Class and struct objc_class*. Here we case the result 4266 // to the pseudo-builtin, because that will be implicitly cast back to the 4267 // redefinition type if an attempt is made to access its fields. 4268 if (LHSTy->isObjCClassType() && 4269 (RHSTy.getDesugaredType() == Context.ObjCClassRedefinitionType)) { 4270 ImpCastExprToType(RHS, LHSTy, CastExpr::CK_BitCast); 4271 return LHSTy; 4272 } 4273 if (RHSTy->isObjCClassType() && 4274 (LHSTy.getDesugaredType() == Context.ObjCClassRedefinitionType)) { 4275 ImpCastExprToType(LHS, RHSTy, CastExpr::CK_BitCast); 4276 return RHSTy; 4277 } 4278 // And the same for struct objc_object* / id 4279 if (LHSTy->isObjCIdType() && 4280 (RHSTy.getDesugaredType() == Context.ObjCIdRedefinitionType)) { 4281 ImpCastExprToType(RHS, LHSTy, CastExpr::CK_BitCast); 4282 return LHSTy; 4283 } 4284 if (RHSTy->isObjCIdType() && 4285 (LHSTy.getDesugaredType() == Context.ObjCIdRedefinitionType)) { 4286 ImpCastExprToType(LHS, RHSTy, CastExpr::CK_BitCast); 4287 return RHSTy; 4288 } 4289 // And the same for struct objc_selector* / SEL 4290 if (Context.isObjCSelType(LHSTy) && 4291 (RHSTy.getDesugaredType() == Context.ObjCSelRedefinitionType)) { 4292 ImpCastExprToType(RHS, LHSTy, CastExpr::CK_BitCast); 4293 return LHSTy; 4294 } 4295 if (Context.isObjCSelType(RHSTy) && 4296 (LHSTy.getDesugaredType() == Context.ObjCSelRedefinitionType)) { 4297 ImpCastExprToType(LHS, RHSTy, CastExpr::CK_BitCast); 4298 return RHSTy; 4299 } 4300 // Check constraints for Objective-C object pointers types. 4301 if (LHSTy->isObjCObjectPointerType() && RHSTy->isObjCObjectPointerType()) { 4302 4303 if (Context.getCanonicalType(LHSTy) == Context.getCanonicalType(RHSTy)) { 4304 // Two identical object pointer types are always compatible. 4305 return LHSTy; 4306 } 4307 const ObjCObjectPointerType *LHSOPT = LHSTy->getAs<ObjCObjectPointerType>(); 4308 const ObjCObjectPointerType *RHSOPT = RHSTy->getAs<ObjCObjectPointerType>(); 4309 QualType compositeType = LHSTy; 4310 4311 // If both operands are interfaces and either operand can be 4312 // assigned to the other, use that type as the composite 4313 // type. This allows 4314 // xxx ? (A*) a : (B*) b 4315 // where B is a subclass of A. 4316 // 4317 // Additionally, as for assignment, if either type is 'id' 4318 // allow silent coercion. Finally, if the types are 4319 // incompatible then make sure to use 'id' as the composite 4320 // type so the result is acceptable for sending messages to. 4321 4322 // FIXME: Consider unifying with 'areComparableObjCPointerTypes'. 4323 // It could return the composite type. 4324 if (Context.canAssignObjCInterfaces(LHSOPT, RHSOPT)) { 4325 compositeType = RHSOPT->isObjCBuiltinType() ? RHSTy : LHSTy; 4326 } else if (Context.canAssignObjCInterfaces(RHSOPT, LHSOPT)) { 4327 compositeType = LHSOPT->isObjCBuiltinType() ? LHSTy : RHSTy; 4328 } else if ((LHSTy->isObjCQualifiedIdType() || 4329 RHSTy->isObjCQualifiedIdType()) && 4330 Context.ObjCQualifiedIdTypesAreCompatible(LHSTy, RHSTy, true)) { 4331 // Need to handle "id<xx>" explicitly. 4332 // GCC allows qualified id and any Objective-C type to devolve to 4333 // id. Currently localizing to here until clear this should be 4334 // part of ObjCQualifiedIdTypesAreCompatible. 4335 compositeType = Context.getObjCIdType(); 4336 } else if (LHSTy->isObjCIdType() || RHSTy->isObjCIdType()) { 4337 compositeType = Context.getObjCIdType(); 4338 } else if (!(compositeType = 4339 Context.areCommonBaseCompatible(LHSOPT, RHSOPT)).isNull()) 4340 ; 4341 else { 4342 Diag(QuestionLoc, diag::ext_typecheck_cond_incompatible_operands) 4343 << LHSTy << RHSTy 4344 << LHS->getSourceRange() << RHS->getSourceRange(); 4345 QualType incompatTy = Context.getObjCIdType(); 4346 ImpCastExprToType(LHS, incompatTy, CastExpr::CK_BitCast); 4347 ImpCastExprToType(RHS, incompatTy, CastExpr::CK_BitCast); 4348 return incompatTy; 4349 } 4350 // The object pointer types are compatible. 4351 ImpCastExprToType(LHS, compositeType, CastExpr::CK_BitCast); 4352 ImpCastExprToType(RHS, compositeType, CastExpr::CK_BitCast); 4353 return compositeType; 4354 } 4355 // Check Objective-C object pointer types and 'void *' 4356 if (LHSTy->isVoidPointerType() && RHSTy->isObjCObjectPointerType()) { 4357 QualType lhptee = LHSTy->getAs<PointerType>()->getPointeeType(); 4358 QualType rhptee = RHSTy->getAs<ObjCObjectPointerType>()->getPointeeType(); 4359 QualType destPointee 4360 = Context.getQualifiedType(lhptee, rhptee.getQualifiers()); 4361 QualType destType = Context.getPointerType(destPointee); 4362 // Add qualifiers if necessary. 4363 ImpCastExprToType(LHS, destType, CastExpr::CK_NoOp); 4364 // Promote to void*. 4365 ImpCastExprToType(RHS, destType, CastExpr::CK_BitCast); 4366 return destType; 4367 } 4368 if (LHSTy->isObjCObjectPointerType() && RHSTy->isVoidPointerType()) { 4369 QualType lhptee = LHSTy->getAs<ObjCObjectPointerType>()->getPointeeType(); 4370 QualType rhptee = RHSTy->getAs<PointerType>()->getPointeeType(); 4371 QualType destPointee 4372 = Context.getQualifiedType(rhptee, lhptee.getQualifiers()); 4373 QualType destType = Context.getPointerType(destPointee); 4374 // Add qualifiers if necessary. 4375 ImpCastExprToType(RHS, destType, CastExpr::CK_NoOp); 4376 // Promote to void*. 4377 ImpCastExprToType(LHS, destType, CastExpr::CK_BitCast); 4378 return destType; 4379 } 4380 return QualType(); 4381} 4382 4383/// ActOnConditionalOp - Parse a ?: operation. Note that 'LHS' may be null 4384/// in the case of a the GNU conditional expr extension. 4385Action::OwningExprResult Sema::ActOnConditionalOp(SourceLocation QuestionLoc, 4386 SourceLocation ColonLoc, 4387 ExprArg Cond, ExprArg LHS, 4388 ExprArg RHS) { 4389 Expr *CondExpr = (Expr *) Cond.get(); 4390 Expr *LHSExpr = (Expr *) LHS.get(), *RHSExpr = (Expr *) RHS.get(); 4391 4392 // If this is the gnu "x ?: y" extension, analyze the types as though the LHS 4393 // was the condition. 4394 bool isLHSNull = LHSExpr == 0; 4395 if (isLHSNull) 4396 LHSExpr = CondExpr; 4397 4398 QualType result = CheckConditionalOperands(CondExpr, LHSExpr, 4399 RHSExpr, QuestionLoc); 4400 if (result.isNull()) 4401 return ExprError(); 4402 4403 Cond.release(); 4404 LHS.release(); 4405 RHS.release(); 4406 return Owned(new (Context) ConditionalOperator(CondExpr, QuestionLoc, 4407 isLHSNull ? 0 : LHSExpr, 4408 ColonLoc, RHSExpr, result)); 4409} 4410 4411// CheckPointerTypesForAssignment - This is a very tricky routine (despite 4412// being closely modeled after the C99 spec:-). The odd characteristic of this 4413// routine is it effectively iqnores the qualifiers on the top level pointee. 4414// This circumvents the usual type rules specified in 6.2.7p1 & 6.7.5.[1-3]. 4415// FIXME: add a couple examples in this comment. 4416Sema::AssignConvertType 4417Sema::CheckPointerTypesForAssignment(QualType lhsType, QualType rhsType) { 4418 QualType lhptee, rhptee; 4419 4420 if ((lhsType->isObjCClassType() && 4421 (rhsType.getDesugaredType() == Context.ObjCClassRedefinitionType)) || 4422 (rhsType->isObjCClassType() && 4423 (lhsType.getDesugaredType() == Context.ObjCClassRedefinitionType))) { 4424 return Compatible; 4425 } 4426 4427 // get the "pointed to" type (ignoring qualifiers at the top level) 4428 lhptee = lhsType->getAs<PointerType>()->getPointeeType(); 4429 rhptee = rhsType->getAs<PointerType>()->getPointeeType(); 4430 4431 // make sure we operate on the canonical type 4432 lhptee = Context.getCanonicalType(lhptee); 4433 rhptee = Context.getCanonicalType(rhptee); 4434 4435 AssignConvertType ConvTy = Compatible; 4436 4437 // C99 6.5.16.1p1: This following citation is common to constraints 4438 // 3 & 4 (below). ...and the type *pointed to* by the left has all the 4439 // qualifiers of the type *pointed to* by the right; 4440 // FIXME: Handle ExtQualType 4441 if (!lhptee.isAtLeastAsQualifiedAs(rhptee)) 4442 ConvTy = CompatiblePointerDiscardsQualifiers; 4443 4444 // C99 6.5.16.1p1 (constraint 4): If one operand is a pointer to an object or 4445 // incomplete type and the other is a pointer to a qualified or unqualified 4446 // version of void... 4447 if (lhptee->isVoidType()) { 4448 if (rhptee->isIncompleteOrObjectType()) 4449 return ConvTy; 4450 4451 // As an extension, we allow cast to/from void* to function pointer. 4452 assert(rhptee->isFunctionType()); 4453 return FunctionVoidPointer; 4454 } 4455 4456 if (rhptee->isVoidType()) { 4457 if (lhptee->isIncompleteOrObjectType()) 4458 return ConvTy; 4459 4460 // As an extension, we allow cast to/from void* to function pointer. 4461 assert(lhptee->isFunctionType()); 4462 return FunctionVoidPointer; 4463 } 4464 // C99 6.5.16.1p1 (constraint 3): both operands are pointers to qualified or 4465 // unqualified versions of compatible types, ... 4466 lhptee = lhptee.getUnqualifiedType(); 4467 rhptee = rhptee.getUnqualifiedType(); 4468 if (!Context.typesAreCompatible(lhptee, rhptee)) { 4469 // Check if the pointee types are compatible ignoring the sign. 4470 // We explicitly check for char so that we catch "char" vs 4471 // "unsigned char" on systems where "char" is unsigned. 4472 if (lhptee->isCharType()) 4473 lhptee = Context.UnsignedCharTy; 4474 else if (lhptee->isSignedIntegerType()) 4475 lhptee = Context.getCorrespondingUnsignedType(lhptee); 4476 4477 if (rhptee->isCharType()) 4478 rhptee = Context.UnsignedCharTy; 4479 else if (rhptee->isSignedIntegerType()) 4480 rhptee = Context.getCorrespondingUnsignedType(rhptee); 4481 4482 if (lhptee == rhptee) { 4483 // Types are compatible ignoring the sign. Qualifier incompatibility 4484 // takes priority over sign incompatibility because the sign 4485 // warning can be disabled. 4486 if (ConvTy != Compatible) 4487 return ConvTy; 4488 return IncompatiblePointerSign; 4489 } 4490 4491 // If we are a multi-level pointer, it's possible that our issue is simply 4492 // one of qualification - e.g. char ** -> const char ** is not allowed. If 4493 // the eventual target type is the same and the pointers have the same 4494 // level of indirection, this must be the issue. 4495 if (lhptee->isPointerType() && rhptee->isPointerType()) { 4496 do { 4497 lhptee = lhptee->getAs<PointerType>()->getPointeeType(); 4498 rhptee = rhptee->getAs<PointerType>()->getPointeeType(); 4499 4500 lhptee = Context.getCanonicalType(lhptee); 4501 rhptee = Context.getCanonicalType(rhptee); 4502 } while (lhptee->isPointerType() && rhptee->isPointerType()); 4503 4504 if (Context.hasSameUnqualifiedType(lhptee, rhptee)) 4505 return IncompatibleNestedPointerQualifiers; 4506 } 4507 4508 // General pointer incompatibility takes priority over qualifiers. 4509 return IncompatiblePointer; 4510 } 4511 return ConvTy; 4512} 4513 4514/// CheckBlockPointerTypesForAssignment - This routine determines whether two 4515/// block pointer types are compatible or whether a block and normal pointer 4516/// are compatible. It is more restrict than comparing two function pointer 4517// types. 4518Sema::AssignConvertType 4519Sema::CheckBlockPointerTypesForAssignment(QualType lhsType, 4520 QualType rhsType) { 4521 QualType lhptee, rhptee; 4522 4523 // get the "pointed to" type (ignoring qualifiers at the top level) 4524 lhptee = lhsType->getAs<BlockPointerType>()->getPointeeType(); 4525 rhptee = rhsType->getAs<BlockPointerType>()->getPointeeType(); 4526 4527 // make sure we operate on the canonical type 4528 lhptee = Context.getCanonicalType(lhptee); 4529 rhptee = Context.getCanonicalType(rhptee); 4530 4531 AssignConvertType ConvTy = Compatible; 4532 4533 // For blocks we enforce that qualifiers are identical. 4534 if (lhptee.getLocalCVRQualifiers() != rhptee.getLocalCVRQualifiers()) 4535 ConvTy = CompatiblePointerDiscardsQualifiers; 4536 4537 if (!getLangOptions().CPlusPlus) { 4538 if (!Context.typesAreBlockPointerCompatible(lhsType, rhsType)) 4539 return IncompatibleBlockPointer; 4540 } 4541 else if (!Context.typesAreCompatible(lhptee, rhptee)) 4542 return IncompatibleBlockPointer; 4543 return ConvTy; 4544} 4545 4546/// CheckObjCPointerTypesForAssignment - Compares two objective-c pointer types 4547/// for assignment compatibility. 4548Sema::AssignConvertType 4549Sema::CheckObjCPointerTypesForAssignment(QualType lhsType, QualType rhsType) { 4550 if (lhsType->isObjCBuiltinType()) { 4551 // Class is not compatible with ObjC object pointers. 4552 if (lhsType->isObjCClassType() && !rhsType->isObjCBuiltinType() && 4553 !rhsType->isObjCQualifiedClassType()) 4554 return IncompatiblePointer; 4555 return Compatible; 4556 } 4557 if (rhsType->isObjCBuiltinType()) { 4558 // Class is not compatible with ObjC object pointers. 4559 if (rhsType->isObjCClassType() && !lhsType->isObjCBuiltinType() && 4560 !lhsType->isObjCQualifiedClassType()) 4561 return IncompatiblePointer; 4562 return Compatible; 4563 } 4564 QualType lhptee = 4565 lhsType->getAs<ObjCObjectPointerType>()->getPointeeType(); 4566 QualType rhptee = 4567 rhsType->getAs<ObjCObjectPointerType>()->getPointeeType(); 4568 // make sure we operate on the canonical type 4569 lhptee = Context.getCanonicalType(lhptee); 4570 rhptee = Context.getCanonicalType(rhptee); 4571 if (!lhptee.isAtLeastAsQualifiedAs(rhptee)) 4572 return CompatiblePointerDiscardsQualifiers; 4573 4574 if (Context.typesAreCompatible(lhsType, rhsType)) 4575 return Compatible; 4576 if (lhsType->isObjCQualifiedIdType() || rhsType->isObjCQualifiedIdType()) 4577 return IncompatibleObjCQualifiedId; 4578 return IncompatiblePointer; 4579} 4580 4581/// CheckAssignmentConstraints (C99 6.5.16) - This routine currently 4582/// has code to accommodate several GCC extensions when type checking 4583/// pointers. Here are some objectionable examples that GCC considers warnings: 4584/// 4585/// int a, *pint; 4586/// short *pshort; 4587/// struct foo *pfoo; 4588/// 4589/// pint = pshort; // warning: assignment from incompatible pointer type 4590/// a = pint; // warning: assignment makes integer from pointer without a cast 4591/// pint = a; // warning: assignment makes pointer from integer without a cast 4592/// pint = pfoo; // warning: assignment from incompatible pointer type 4593/// 4594/// As a result, the code for dealing with pointers is more complex than the 4595/// C99 spec dictates. 4596/// 4597Sema::AssignConvertType 4598Sema::CheckAssignmentConstraints(QualType lhsType, QualType rhsType) { 4599 // Get canonical types. We're not formatting these types, just comparing 4600 // them. 4601 lhsType = Context.getCanonicalType(lhsType).getUnqualifiedType(); 4602 rhsType = Context.getCanonicalType(rhsType).getUnqualifiedType(); 4603 4604 if (lhsType == rhsType) 4605 return Compatible; // Common case: fast path an exact match. 4606 4607 if ((lhsType->isObjCClassType() && 4608 (rhsType.getDesugaredType() == Context.ObjCClassRedefinitionType)) || 4609 (rhsType->isObjCClassType() && 4610 (lhsType.getDesugaredType() == Context.ObjCClassRedefinitionType))) { 4611 return Compatible; 4612 } 4613 4614 // If the left-hand side is a reference type, then we are in a 4615 // (rare!) case where we've allowed the use of references in C, 4616 // e.g., as a parameter type in a built-in function. In this case, 4617 // just make sure that the type referenced is compatible with the 4618 // right-hand side type. The caller is responsible for adjusting 4619 // lhsType so that the resulting expression does not have reference 4620 // type. 4621 if (const ReferenceType *lhsTypeRef = lhsType->getAs<ReferenceType>()) { 4622 if (Context.typesAreCompatible(lhsTypeRef->getPointeeType(), rhsType)) 4623 return Compatible; 4624 return Incompatible; 4625 } 4626 // Allow scalar to ExtVector assignments, and assignments of an ExtVector type 4627 // to the same ExtVector type. 4628 if (lhsType->isExtVectorType()) { 4629 if (rhsType->isExtVectorType()) 4630 return lhsType == rhsType ? Compatible : Incompatible; 4631 if (!rhsType->isVectorType() && rhsType->isArithmeticType()) 4632 return Compatible; 4633 } 4634 4635 if (lhsType->isVectorType() || rhsType->isVectorType()) { 4636 // If we are allowing lax vector conversions, and LHS and RHS are both 4637 // vectors, the total size only needs to be the same. This is a bitcast; 4638 // no bits are changed but the result type is different. 4639 if (getLangOptions().LaxVectorConversions && 4640 lhsType->isVectorType() && rhsType->isVectorType()) { 4641 if (Context.getTypeSize(lhsType) == Context.getTypeSize(rhsType)) 4642 return IncompatibleVectors; 4643 } 4644 return Incompatible; 4645 } 4646 4647 if (lhsType->isArithmeticType() && rhsType->isArithmeticType()) 4648 return Compatible; 4649 4650 if (isa<PointerType>(lhsType)) { 4651 if (rhsType->isIntegerType()) 4652 return IntToPointer; 4653 4654 if (isa<PointerType>(rhsType)) 4655 return CheckPointerTypesForAssignment(lhsType, rhsType); 4656 4657 // In general, C pointers are not compatible with ObjC object pointers. 4658 if (isa<ObjCObjectPointerType>(rhsType)) { 4659 if (lhsType->isVoidPointerType()) // an exception to the rule. 4660 return Compatible; 4661 return IncompatiblePointer; 4662 } 4663 if (rhsType->getAs<BlockPointerType>()) { 4664 if (lhsType->getAs<PointerType>()->getPointeeType()->isVoidType()) 4665 return Compatible; 4666 4667 // Treat block pointers as objects. 4668 if (getLangOptions().ObjC1 && lhsType->isObjCIdType()) 4669 return Compatible; 4670 } 4671 return Incompatible; 4672 } 4673 4674 if (isa<BlockPointerType>(lhsType)) { 4675 if (rhsType->isIntegerType()) 4676 return IntToBlockPointer; 4677 4678 // Treat block pointers as objects. 4679 if (getLangOptions().ObjC1 && rhsType->isObjCIdType()) 4680 return Compatible; 4681 4682 if (rhsType->isBlockPointerType()) 4683 return CheckBlockPointerTypesForAssignment(lhsType, rhsType); 4684 4685 if (const PointerType *RHSPT = rhsType->getAs<PointerType>()) { 4686 if (RHSPT->getPointeeType()->isVoidType()) 4687 return Compatible; 4688 } 4689 return Incompatible; 4690 } 4691 4692 if (isa<ObjCObjectPointerType>(lhsType)) { 4693 if (rhsType->isIntegerType()) 4694 return IntToPointer; 4695 4696 // In general, C pointers are not compatible with ObjC object pointers. 4697 if (isa<PointerType>(rhsType)) { 4698 if (rhsType->isVoidPointerType()) // an exception to the rule. 4699 return Compatible; 4700 return IncompatiblePointer; 4701 } 4702 if (rhsType->isObjCObjectPointerType()) { 4703 return CheckObjCPointerTypesForAssignment(lhsType, rhsType); 4704 } 4705 if (const PointerType *RHSPT = rhsType->getAs<PointerType>()) { 4706 if (RHSPT->getPointeeType()->isVoidType()) 4707 return Compatible; 4708 } 4709 // Treat block pointers as objects. 4710 if (rhsType->isBlockPointerType()) 4711 return Compatible; 4712 return Incompatible; 4713 } 4714 if (isa<PointerType>(rhsType)) { 4715 // C99 6.5.16.1p1: the left operand is _Bool and the right is a pointer. 4716 if (lhsType == Context.BoolTy) 4717 return Compatible; 4718 4719 if (lhsType->isIntegerType()) 4720 return PointerToInt; 4721 4722 if (isa<PointerType>(lhsType)) 4723 return CheckPointerTypesForAssignment(lhsType, rhsType); 4724 4725 if (isa<BlockPointerType>(lhsType) && 4726 rhsType->getAs<PointerType>()->getPointeeType()->isVoidType()) 4727 return Compatible; 4728 return Incompatible; 4729 } 4730 if (isa<ObjCObjectPointerType>(rhsType)) { 4731 // C99 6.5.16.1p1: the left operand is _Bool and the right is a pointer. 4732 if (lhsType == Context.BoolTy) 4733 return Compatible; 4734 4735 if (lhsType->isIntegerType()) 4736 return PointerToInt; 4737 4738 // In general, C pointers are not compatible with ObjC object pointers. 4739 if (isa<PointerType>(lhsType)) { 4740 if (lhsType->isVoidPointerType()) // an exception to the rule. 4741 return Compatible; 4742 return IncompatiblePointer; 4743 } 4744 if (isa<BlockPointerType>(lhsType) && 4745 rhsType->getAs<PointerType>()->getPointeeType()->isVoidType()) 4746 return Compatible; 4747 return Incompatible; 4748 } 4749 4750 if (isa<TagType>(lhsType) && isa<TagType>(rhsType)) { 4751 if (Context.typesAreCompatible(lhsType, rhsType)) 4752 return Compatible; 4753 } 4754 return Incompatible; 4755} 4756 4757/// \brief Constructs a transparent union from an expression that is 4758/// used to initialize the transparent union. 4759static void ConstructTransparentUnion(ASTContext &C, Expr *&E, 4760 QualType UnionType, FieldDecl *Field) { 4761 // Build an initializer list that designates the appropriate member 4762 // of the transparent union. 4763 InitListExpr *Initializer = new (C) InitListExpr(C, SourceLocation(), 4764 &E, 1, 4765 SourceLocation()); 4766 Initializer->setType(UnionType); 4767 Initializer->setInitializedFieldInUnion(Field); 4768 4769 // Build a compound literal constructing a value of the transparent 4770 // union type from this initializer list. 4771 TypeSourceInfo *unionTInfo = C.getTrivialTypeSourceInfo(UnionType); 4772 E = new (C) CompoundLiteralExpr(SourceLocation(), unionTInfo, UnionType, 4773 Initializer, false); 4774} 4775 4776Sema::AssignConvertType 4777Sema::CheckTransparentUnionArgumentConstraints(QualType ArgType, Expr *&rExpr) { 4778 QualType FromType = rExpr->getType(); 4779 4780 // If the ArgType is a Union type, we want to handle a potential 4781 // transparent_union GCC extension. 4782 const RecordType *UT = ArgType->getAsUnionType(); 4783 if (!UT || !UT->getDecl()->hasAttr<TransparentUnionAttr>()) 4784 return Incompatible; 4785 4786 // The field to initialize within the transparent union. 4787 RecordDecl *UD = UT->getDecl(); 4788 FieldDecl *InitField = 0; 4789 // It's compatible if the expression matches any of the fields. 4790 for (RecordDecl::field_iterator it = UD->field_begin(), 4791 itend = UD->field_end(); 4792 it != itend; ++it) { 4793 if (it->getType()->isPointerType()) { 4794 // If the transparent union contains a pointer type, we allow: 4795 // 1) void pointer 4796 // 2) null pointer constant 4797 if (FromType->isPointerType()) 4798 if (FromType->getAs<PointerType>()->getPointeeType()->isVoidType()) { 4799 ImpCastExprToType(rExpr, it->getType(), CastExpr::CK_BitCast); 4800 InitField = *it; 4801 break; 4802 } 4803 4804 if (rExpr->isNullPointerConstant(Context, 4805 Expr::NPC_ValueDependentIsNull)) { 4806 ImpCastExprToType(rExpr, it->getType(), CastExpr::CK_IntegralToPointer); 4807 InitField = *it; 4808 break; 4809 } 4810 } 4811 4812 if (CheckAssignmentConstraints(it->getType(), rExpr->getType()) 4813 == Compatible) { 4814 InitField = *it; 4815 break; 4816 } 4817 } 4818 4819 if (!InitField) 4820 return Incompatible; 4821 4822 ConstructTransparentUnion(Context, rExpr, ArgType, InitField); 4823 return Compatible; 4824} 4825 4826Sema::AssignConvertType 4827Sema::CheckSingleAssignmentConstraints(QualType lhsType, Expr *&rExpr) { 4828 if (getLangOptions().CPlusPlus) { 4829 if (!lhsType->isRecordType()) { 4830 // C++ 5.17p3: If the left operand is not of class type, the 4831 // expression is implicitly converted (C++ 4) to the 4832 // cv-unqualified type of the left operand. 4833 if (PerformImplicitConversion(rExpr, lhsType.getUnqualifiedType(), 4834 AA_Assigning)) 4835 return Incompatible; 4836 return Compatible; 4837 } 4838 4839 // FIXME: Currently, we fall through and treat C++ classes like C 4840 // structures. 4841 } 4842 4843 // C99 6.5.16.1p1: the left operand is a pointer and the right is 4844 // a null pointer constant. 4845 if ((lhsType->isPointerType() || 4846 lhsType->isObjCObjectPointerType() || 4847 lhsType->isBlockPointerType()) 4848 && rExpr->isNullPointerConstant(Context, 4849 Expr::NPC_ValueDependentIsNull)) { 4850 ImpCastExprToType(rExpr, lhsType, CastExpr::CK_Unknown); 4851 return Compatible; 4852 } 4853 4854 // This check seems unnatural, however it is necessary to ensure the proper 4855 // conversion of functions/arrays. If the conversion were done for all 4856 // DeclExpr's (created by ActOnIdExpression), it would mess up the unary 4857 // expressions that surpress this implicit conversion (&, sizeof). 4858 // 4859 // Suppress this for references: C++ 8.5.3p5. 4860 if (!lhsType->isReferenceType()) 4861 DefaultFunctionArrayLvalueConversion(rExpr); 4862 4863 Sema::AssignConvertType result = 4864 CheckAssignmentConstraints(lhsType, rExpr->getType()); 4865 4866 // C99 6.5.16.1p2: The value of the right operand is converted to the 4867 // type of the assignment expression. 4868 // CheckAssignmentConstraints allows the left-hand side to be a reference, 4869 // so that we can use references in built-in functions even in C. 4870 // The getNonReferenceType() call makes sure that the resulting expression 4871 // does not have reference type. 4872 if (result != Incompatible && rExpr->getType() != lhsType) 4873 ImpCastExprToType(rExpr, lhsType.getNonReferenceType(), 4874 CastExpr::CK_Unknown); 4875 return result; 4876} 4877 4878QualType Sema::InvalidOperands(SourceLocation Loc, Expr *&lex, Expr *&rex) { 4879 Diag(Loc, diag::err_typecheck_invalid_operands) 4880 << lex->getType() << rex->getType() 4881 << lex->getSourceRange() << rex->getSourceRange(); 4882 return QualType(); 4883} 4884 4885QualType Sema::CheckVectorOperands(SourceLocation Loc, Expr *&lex, Expr *&rex) { 4886 // For conversion purposes, we ignore any qualifiers. 4887 // For example, "const float" and "float" are equivalent. 4888 QualType lhsType = 4889 Context.getCanonicalType(lex->getType()).getUnqualifiedType(); 4890 QualType rhsType = 4891 Context.getCanonicalType(rex->getType()).getUnqualifiedType(); 4892 4893 // If the vector types are identical, return. 4894 if (lhsType == rhsType) 4895 return lhsType; 4896 4897 // Handle the case of a vector & extvector type of the same size and element 4898 // type. It would be nice if we only had one vector type someday. 4899 if (getLangOptions().LaxVectorConversions) { 4900 // FIXME: Should we warn here? 4901 if (const VectorType *LV = lhsType->getAs<VectorType>()) { 4902 if (const VectorType *RV = rhsType->getAs<VectorType>()) 4903 if (LV->getElementType() == RV->getElementType() && 4904 LV->getNumElements() == RV->getNumElements()) { 4905 if (lhsType->isExtVectorType()) { 4906 ImpCastExprToType(rex, lhsType, CastExpr::CK_BitCast); 4907 return lhsType; 4908 } 4909 4910 ImpCastExprToType(lex, rhsType, CastExpr::CK_BitCast); 4911 return rhsType; 4912 } 4913 } 4914 } 4915 4916 // Canonicalize the ExtVector to the LHS, remember if we swapped so we can 4917 // swap back (so that we don't reverse the inputs to a subtract, for instance. 4918 bool swapped = false; 4919 if (rhsType->isExtVectorType()) { 4920 swapped = true; 4921 std::swap(rex, lex); 4922 std::swap(rhsType, lhsType); 4923 } 4924 4925 // Handle the case of an ext vector and scalar. 4926 if (const ExtVectorType *LV = lhsType->getAs<ExtVectorType>()) { 4927 QualType EltTy = LV->getElementType(); 4928 if (EltTy->isIntegralType() && rhsType->isIntegralType()) { 4929 if (Context.getIntegerTypeOrder(EltTy, rhsType) >= 0) { 4930 ImpCastExprToType(rex, lhsType, CastExpr::CK_IntegralCast); 4931 if (swapped) std::swap(rex, lex); 4932 return lhsType; 4933 } 4934 } 4935 if (EltTy->isRealFloatingType() && rhsType->isScalarType() && 4936 rhsType->isRealFloatingType()) { 4937 if (Context.getFloatingTypeOrder(EltTy, rhsType) >= 0) { 4938 ImpCastExprToType(rex, lhsType, CastExpr::CK_FloatingCast); 4939 if (swapped) std::swap(rex, lex); 4940 return lhsType; 4941 } 4942 } 4943 } 4944 4945 // Vectors of different size or scalar and non-ext-vector are errors. 4946 Diag(Loc, diag::err_typecheck_vector_not_convertable) 4947 << lex->getType() << rex->getType() 4948 << lex->getSourceRange() << rex->getSourceRange(); 4949 return QualType(); 4950} 4951 4952QualType Sema::CheckMultiplyDivideOperands( 4953 Expr *&lex, Expr *&rex, SourceLocation Loc, bool isCompAssign, bool isDiv) { 4954 if (lex->getType()->isVectorType() || rex->getType()->isVectorType()) 4955 return CheckVectorOperands(Loc, lex, rex); 4956 4957 QualType compType = UsualArithmeticConversions(lex, rex, isCompAssign); 4958 4959 if (!lex->getType()->isArithmeticType() || 4960 !rex->getType()->isArithmeticType()) 4961 return InvalidOperands(Loc, lex, rex); 4962 4963 // Check for division by zero. 4964 if (isDiv && 4965 rex->isNullPointerConstant(Context, Expr::NPC_ValueDependentIsNotNull)) 4966 DiagRuntimeBehavior(Loc, PDiag(diag::warn_division_by_zero) 4967 << rex->getSourceRange()); 4968 4969 return compType; 4970} 4971 4972QualType Sema::CheckRemainderOperands( 4973 Expr *&lex, Expr *&rex, SourceLocation Loc, bool isCompAssign) { 4974 if (lex->getType()->isVectorType() || rex->getType()->isVectorType()) { 4975 if (lex->getType()->isIntegerType() && rex->getType()->isIntegerType()) 4976 return CheckVectorOperands(Loc, lex, rex); 4977 return InvalidOperands(Loc, lex, rex); 4978 } 4979 4980 QualType compType = UsualArithmeticConversions(lex, rex, isCompAssign); 4981 4982 if (!lex->getType()->isIntegerType() || !rex->getType()->isIntegerType()) 4983 return InvalidOperands(Loc, lex, rex); 4984 4985 // Check for remainder by zero. 4986 if (rex->isNullPointerConstant(Context, Expr::NPC_ValueDependentIsNotNull)) 4987 DiagRuntimeBehavior(Loc, PDiag(diag::warn_remainder_by_zero) 4988 << rex->getSourceRange()); 4989 4990 return compType; 4991} 4992 4993QualType Sema::CheckAdditionOperands( // C99 6.5.6 4994 Expr *&lex, Expr *&rex, SourceLocation Loc, QualType* CompLHSTy) { 4995 if (lex->getType()->isVectorType() || rex->getType()->isVectorType()) { 4996 QualType compType = CheckVectorOperands(Loc, lex, rex); 4997 if (CompLHSTy) *CompLHSTy = compType; 4998 return compType; 4999 } 5000 5001 QualType compType = UsualArithmeticConversions(lex, rex, CompLHSTy); 5002 5003 // handle the common case first (both operands are arithmetic). 5004 if (lex->getType()->isArithmeticType() && 5005 rex->getType()->isArithmeticType()) { 5006 if (CompLHSTy) *CompLHSTy = compType; 5007 return compType; 5008 } 5009 5010 // Put any potential pointer into PExp 5011 Expr* PExp = lex, *IExp = rex; 5012 if (IExp->getType()->isAnyPointerType()) 5013 std::swap(PExp, IExp); 5014 5015 if (PExp->getType()->isAnyPointerType()) { 5016 5017 if (IExp->getType()->isIntegerType()) { 5018 QualType PointeeTy = PExp->getType()->getPointeeType(); 5019 5020 // Check for arithmetic on pointers to incomplete types. 5021 if (PointeeTy->isVoidType()) { 5022 if (getLangOptions().CPlusPlus) { 5023 Diag(Loc, diag::err_typecheck_pointer_arith_void_type) 5024 << lex->getSourceRange() << rex->getSourceRange(); 5025 return QualType(); 5026 } 5027 5028 // GNU extension: arithmetic on pointer to void 5029 Diag(Loc, diag::ext_gnu_void_ptr) 5030 << lex->getSourceRange() << rex->getSourceRange(); 5031 } else if (PointeeTy->isFunctionType()) { 5032 if (getLangOptions().CPlusPlus) { 5033 Diag(Loc, diag::err_typecheck_pointer_arith_function_type) 5034 << lex->getType() << lex->getSourceRange(); 5035 return QualType(); 5036 } 5037 5038 // GNU extension: arithmetic on pointer to function 5039 Diag(Loc, diag::ext_gnu_ptr_func_arith) 5040 << lex->getType() << lex->getSourceRange(); 5041 } else { 5042 // Check if we require a complete type. 5043 if (((PExp->getType()->isPointerType() && 5044 !PExp->getType()->isDependentType()) || 5045 PExp->getType()->isObjCObjectPointerType()) && 5046 RequireCompleteType(Loc, PointeeTy, 5047 PDiag(diag::err_typecheck_arithmetic_incomplete_type) 5048 << PExp->getSourceRange() 5049 << PExp->getType())) 5050 return QualType(); 5051 } 5052 // Diagnose bad cases where we step over interface counts. 5053 if (PointeeTy->isObjCObjectType() && LangOpts.ObjCNonFragileABI) { 5054 Diag(Loc, diag::err_arithmetic_nonfragile_interface) 5055 << PointeeTy << PExp->getSourceRange(); 5056 return QualType(); 5057 } 5058 5059 if (CompLHSTy) { 5060 QualType LHSTy = Context.isPromotableBitField(lex); 5061 if (LHSTy.isNull()) { 5062 LHSTy = lex->getType(); 5063 if (LHSTy->isPromotableIntegerType()) 5064 LHSTy = Context.getPromotedIntegerType(LHSTy); 5065 } 5066 *CompLHSTy = LHSTy; 5067 } 5068 return PExp->getType(); 5069 } 5070 } 5071 5072 return InvalidOperands(Loc, lex, rex); 5073} 5074 5075// C99 6.5.6 5076QualType Sema::CheckSubtractionOperands(Expr *&lex, Expr *&rex, 5077 SourceLocation Loc, QualType* CompLHSTy) { 5078 if (lex->getType()->isVectorType() || rex->getType()->isVectorType()) { 5079 QualType compType = CheckVectorOperands(Loc, lex, rex); 5080 if (CompLHSTy) *CompLHSTy = compType; 5081 return compType; 5082 } 5083 5084 QualType compType = UsualArithmeticConversions(lex, rex, CompLHSTy); 5085 5086 // Enforce type constraints: C99 6.5.6p3. 5087 5088 // Handle the common case first (both operands are arithmetic). 5089 if (lex->getType()->isArithmeticType() 5090 && rex->getType()->isArithmeticType()) { 5091 if (CompLHSTy) *CompLHSTy = compType; 5092 return compType; 5093 } 5094 5095 // Either ptr - int or ptr - ptr. 5096 if (lex->getType()->isAnyPointerType()) { 5097 QualType lpointee = lex->getType()->getPointeeType(); 5098 5099 // The LHS must be an completely-defined object type. 5100 5101 bool ComplainAboutVoid = false; 5102 Expr *ComplainAboutFunc = 0; 5103 if (lpointee->isVoidType()) { 5104 if (getLangOptions().CPlusPlus) { 5105 Diag(Loc, diag::err_typecheck_pointer_arith_void_type) 5106 << lex->getSourceRange() << rex->getSourceRange(); 5107 return QualType(); 5108 } 5109 5110 // GNU C extension: arithmetic on pointer to void 5111 ComplainAboutVoid = true; 5112 } else if (lpointee->isFunctionType()) { 5113 if (getLangOptions().CPlusPlus) { 5114 Diag(Loc, diag::err_typecheck_pointer_arith_function_type) 5115 << lex->getType() << lex->getSourceRange(); 5116 return QualType(); 5117 } 5118 5119 // GNU C extension: arithmetic on pointer to function 5120 ComplainAboutFunc = lex; 5121 } else if (!lpointee->isDependentType() && 5122 RequireCompleteType(Loc, lpointee, 5123 PDiag(diag::err_typecheck_sub_ptr_object) 5124 << lex->getSourceRange() 5125 << lex->getType())) 5126 return QualType(); 5127 5128 // Diagnose bad cases where we step over interface counts. 5129 if (lpointee->isObjCObjectType() && LangOpts.ObjCNonFragileABI) { 5130 Diag(Loc, diag::err_arithmetic_nonfragile_interface) 5131 << lpointee << lex->getSourceRange(); 5132 return QualType(); 5133 } 5134 5135 // The result type of a pointer-int computation is the pointer type. 5136 if (rex->getType()->isIntegerType()) { 5137 if (ComplainAboutVoid) 5138 Diag(Loc, diag::ext_gnu_void_ptr) 5139 << lex->getSourceRange() << rex->getSourceRange(); 5140 if (ComplainAboutFunc) 5141 Diag(Loc, diag::ext_gnu_ptr_func_arith) 5142 << ComplainAboutFunc->getType() 5143 << ComplainAboutFunc->getSourceRange(); 5144 5145 if (CompLHSTy) *CompLHSTy = lex->getType(); 5146 return lex->getType(); 5147 } 5148 5149 // Handle pointer-pointer subtractions. 5150 if (const PointerType *RHSPTy = rex->getType()->getAs<PointerType>()) { 5151 QualType rpointee = RHSPTy->getPointeeType(); 5152 5153 // RHS must be a completely-type object type. 5154 // Handle the GNU void* extension. 5155 if (rpointee->isVoidType()) { 5156 if (getLangOptions().CPlusPlus) { 5157 Diag(Loc, diag::err_typecheck_pointer_arith_void_type) 5158 << lex->getSourceRange() << rex->getSourceRange(); 5159 return QualType(); 5160 } 5161 5162 ComplainAboutVoid = true; 5163 } else if (rpointee->isFunctionType()) { 5164 if (getLangOptions().CPlusPlus) { 5165 Diag(Loc, diag::err_typecheck_pointer_arith_function_type) 5166 << rex->getType() << rex->getSourceRange(); 5167 return QualType(); 5168 } 5169 5170 // GNU extension: arithmetic on pointer to function 5171 if (!ComplainAboutFunc) 5172 ComplainAboutFunc = rex; 5173 } else if (!rpointee->isDependentType() && 5174 RequireCompleteType(Loc, rpointee, 5175 PDiag(diag::err_typecheck_sub_ptr_object) 5176 << rex->getSourceRange() 5177 << rex->getType())) 5178 return QualType(); 5179 5180 if (getLangOptions().CPlusPlus) { 5181 // Pointee types must be the same: C++ [expr.add] 5182 if (!Context.hasSameUnqualifiedType(lpointee, rpointee)) { 5183 Diag(Loc, diag::err_typecheck_sub_ptr_compatible) 5184 << lex->getType() << rex->getType() 5185 << lex->getSourceRange() << rex->getSourceRange(); 5186 return QualType(); 5187 } 5188 } else { 5189 // Pointee types must be compatible C99 6.5.6p3 5190 if (!Context.typesAreCompatible( 5191 Context.getCanonicalType(lpointee).getUnqualifiedType(), 5192 Context.getCanonicalType(rpointee).getUnqualifiedType())) { 5193 Diag(Loc, diag::err_typecheck_sub_ptr_compatible) 5194 << lex->getType() << rex->getType() 5195 << lex->getSourceRange() << rex->getSourceRange(); 5196 return QualType(); 5197 } 5198 } 5199 5200 if (ComplainAboutVoid) 5201 Diag(Loc, diag::ext_gnu_void_ptr) 5202 << lex->getSourceRange() << rex->getSourceRange(); 5203 if (ComplainAboutFunc) 5204 Diag(Loc, diag::ext_gnu_ptr_func_arith) 5205 << ComplainAboutFunc->getType() 5206 << ComplainAboutFunc->getSourceRange(); 5207 5208 if (CompLHSTy) *CompLHSTy = lex->getType(); 5209 return Context.getPointerDiffType(); 5210 } 5211 } 5212 5213 return InvalidOperands(Loc, lex, rex); 5214} 5215 5216// C99 6.5.7 5217QualType Sema::CheckShiftOperands(Expr *&lex, Expr *&rex, SourceLocation Loc, 5218 bool isCompAssign) { 5219 // C99 6.5.7p2: Each of the operands shall have integer type. 5220 if (!lex->getType()->isIntegerType() || !rex->getType()->isIntegerType()) 5221 return InvalidOperands(Loc, lex, rex); 5222 5223 // Vector shifts promote their scalar inputs to vector type. 5224 if (lex->getType()->isVectorType() || rex->getType()->isVectorType()) 5225 return CheckVectorOperands(Loc, lex, rex); 5226 5227 // Shifts don't perform usual arithmetic conversions, they just do integer 5228 // promotions on each operand. C99 6.5.7p3 5229 QualType LHSTy = Context.isPromotableBitField(lex); 5230 if (LHSTy.isNull()) { 5231 LHSTy = lex->getType(); 5232 if (LHSTy->isPromotableIntegerType()) 5233 LHSTy = Context.getPromotedIntegerType(LHSTy); 5234 } 5235 if (!isCompAssign) 5236 ImpCastExprToType(lex, LHSTy, CastExpr::CK_IntegralCast); 5237 5238 UsualUnaryConversions(rex); 5239 5240 // Sanity-check shift operands 5241 llvm::APSInt Right; 5242 // Check right/shifter operand 5243 if (!rex->isValueDependent() && 5244 rex->isIntegerConstantExpr(Right, Context)) { 5245 if (Right.isNegative()) 5246 Diag(Loc, diag::warn_shift_negative) << rex->getSourceRange(); 5247 else { 5248 llvm::APInt LeftBits(Right.getBitWidth(), 5249 Context.getTypeSize(lex->getType())); 5250 if (Right.uge(LeftBits)) 5251 Diag(Loc, diag::warn_shift_gt_typewidth) << rex->getSourceRange(); 5252 } 5253 } 5254 5255 // "The type of the result is that of the promoted left operand." 5256 return LHSTy; 5257} 5258 5259// C99 6.5.8, C++ [expr.rel] 5260QualType Sema::CheckCompareOperands(Expr *&lex, Expr *&rex, SourceLocation Loc, 5261 unsigned OpaqueOpc, bool isRelational) { 5262 BinaryOperator::Opcode Opc = (BinaryOperator::Opcode)OpaqueOpc; 5263 5264 // Handle vector comparisons separately. 5265 if (lex->getType()->isVectorType() || rex->getType()->isVectorType()) 5266 return CheckVectorCompareOperands(lex, rex, Loc, isRelational); 5267 5268 // C99 6.5.8p3 / C99 6.5.9p4 5269 if (lex->getType()->isArithmeticType() && rex->getType()->isArithmeticType()) 5270 UsualArithmeticConversions(lex, rex); 5271 else { 5272 UsualUnaryConversions(lex); 5273 UsualUnaryConversions(rex); 5274 } 5275 QualType lType = lex->getType(); 5276 QualType rType = rex->getType(); 5277 5278 if (!lType->isFloatingType() 5279 && !(lType->isBlockPointerType() && isRelational)) { 5280 // For non-floating point types, check for self-comparisons of the form 5281 // x == x, x != x, x < x, etc. These always evaluate to a constant, and 5282 // often indicate logic errors in the program. 5283 // NOTE: Don't warn about comparisons of enum constants. These can arise 5284 // from macro expansions, and are usually quite deliberate. 5285 Expr *LHSStripped = lex->IgnoreParens(); 5286 Expr *RHSStripped = rex->IgnoreParens(); 5287 if (DeclRefExpr* DRL = dyn_cast<DeclRefExpr>(LHSStripped)) 5288 if (DeclRefExpr* DRR = dyn_cast<DeclRefExpr>(RHSStripped)) 5289 if (DRL->getDecl() == DRR->getDecl() && 5290 !isa<EnumConstantDecl>(DRL->getDecl())) 5291 DiagRuntimeBehavior(Loc, PDiag(diag::warn_selfcomparison)); 5292 5293 if (isa<CastExpr>(LHSStripped)) 5294 LHSStripped = LHSStripped->IgnoreParenCasts(); 5295 if (isa<CastExpr>(RHSStripped)) 5296 RHSStripped = RHSStripped->IgnoreParenCasts(); 5297 5298 // Warn about comparisons against a string constant (unless the other 5299 // operand is null), the user probably wants strcmp. 5300 Expr *literalString = 0; 5301 Expr *literalStringStripped = 0; 5302 if ((isa<StringLiteral>(LHSStripped) || isa<ObjCEncodeExpr>(LHSStripped)) && 5303 !RHSStripped->isNullPointerConstant(Context, 5304 Expr::NPC_ValueDependentIsNull)) { 5305 literalString = lex; 5306 literalStringStripped = LHSStripped; 5307 } else if ((isa<StringLiteral>(RHSStripped) || 5308 isa<ObjCEncodeExpr>(RHSStripped)) && 5309 !LHSStripped->isNullPointerConstant(Context, 5310 Expr::NPC_ValueDependentIsNull)) { 5311 literalString = rex; 5312 literalStringStripped = RHSStripped; 5313 } 5314 5315 if (literalString) { 5316 std::string resultComparison; 5317 switch (Opc) { 5318 case BinaryOperator::LT: resultComparison = ") < 0"; break; 5319 case BinaryOperator::GT: resultComparison = ") > 0"; break; 5320 case BinaryOperator::LE: resultComparison = ") <= 0"; break; 5321 case BinaryOperator::GE: resultComparison = ") >= 0"; break; 5322 case BinaryOperator::EQ: resultComparison = ") == 0"; break; 5323 case BinaryOperator::NE: resultComparison = ") != 0"; break; 5324 default: assert(false && "Invalid comparison operator"); 5325 } 5326 5327 DiagRuntimeBehavior(Loc, 5328 PDiag(diag::warn_stringcompare) 5329 << isa<ObjCEncodeExpr>(literalStringStripped) 5330 << literalString->getSourceRange()); 5331 } 5332 } 5333 5334 // The result of comparisons is 'bool' in C++, 'int' in C. 5335 QualType ResultTy = getLangOptions().CPlusPlus ? Context.BoolTy:Context.IntTy; 5336 5337 if (isRelational) { 5338 if (lType->isRealType() && rType->isRealType()) 5339 return ResultTy; 5340 } else { 5341 // Check for comparisons of floating point operands using != and ==. 5342 if (lType->isFloatingType() && rType->isFloatingType()) 5343 CheckFloatComparison(Loc,lex,rex); 5344 5345 if (lType->isArithmeticType() && rType->isArithmeticType()) 5346 return ResultTy; 5347 } 5348 5349 bool LHSIsNull = lex->isNullPointerConstant(Context, 5350 Expr::NPC_ValueDependentIsNull); 5351 bool RHSIsNull = rex->isNullPointerConstant(Context, 5352 Expr::NPC_ValueDependentIsNull); 5353 5354 // All of the following pointer related warnings are GCC extensions, except 5355 // when handling null pointer constants. One day, we can consider making them 5356 // errors (when -pedantic-errors is enabled). 5357 if (lType->isPointerType() && rType->isPointerType()) { // C99 6.5.8p2 5358 QualType LCanPointeeTy = 5359 Context.getCanonicalType(lType->getAs<PointerType>()->getPointeeType()); 5360 QualType RCanPointeeTy = 5361 Context.getCanonicalType(rType->getAs<PointerType>()->getPointeeType()); 5362 5363 if (getLangOptions().CPlusPlus) { 5364 if (LCanPointeeTy == RCanPointeeTy) 5365 return ResultTy; 5366 if (!isRelational && 5367 (LCanPointeeTy->isVoidType() || RCanPointeeTy->isVoidType())) { 5368 // Valid unless comparison between non-null pointer and function pointer 5369 // This is a gcc extension compatibility comparison. 5370 if ((LCanPointeeTy->isFunctionType() || RCanPointeeTy->isFunctionType()) 5371 && !LHSIsNull && !RHSIsNull) { 5372 Diag(Loc, diag::ext_typecheck_comparison_of_fptr_to_void) 5373 << lType << rType << lex->getSourceRange() << rex->getSourceRange(); 5374 ImpCastExprToType(rex, lType, CastExpr::CK_BitCast); 5375 return ResultTy; 5376 } 5377 } 5378 // C++ [expr.rel]p2: 5379 // [...] Pointer conversions (4.10) and qualification 5380 // conversions (4.4) are performed on pointer operands (or on 5381 // a pointer operand and a null pointer constant) to bring 5382 // them to their composite pointer type. [...] 5383 // 5384 // C++ [expr.eq]p1 uses the same notion for (in)equality 5385 // comparisons of pointers. 5386 bool NonStandardCompositeType = false; 5387 QualType T = FindCompositePointerType(Loc, lex, rex, 5388 isSFINAEContext()? 0 : &NonStandardCompositeType); 5389 if (T.isNull()) { 5390 Diag(Loc, diag::err_typecheck_comparison_of_distinct_pointers) 5391 << lType << rType << lex->getSourceRange() << rex->getSourceRange(); 5392 return QualType(); 5393 } else if (NonStandardCompositeType) { 5394 Diag(Loc, 5395 diag::ext_typecheck_comparison_of_distinct_pointers_nonstandard) 5396 << lType << rType << T 5397 << lex->getSourceRange() << rex->getSourceRange(); 5398 } 5399 5400 ImpCastExprToType(lex, T, CastExpr::CK_BitCast); 5401 ImpCastExprToType(rex, T, CastExpr::CK_BitCast); 5402 return ResultTy; 5403 } 5404 // C99 6.5.9p2 and C99 6.5.8p2 5405 if (Context.typesAreCompatible(LCanPointeeTy.getUnqualifiedType(), 5406 RCanPointeeTy.getUnqualifiedType())) { 5407 // Valid unless a relational comparison of function pointers 5408 if (isRelational && LCanPointeeTy->isFunctionType()) { 5409 Diag(Loc, diag::ext_typecheck_ordered_comparison_of_function_pointers) 5410 << lType << rType << lex->getSourceRange() << rex->getSourceRange(); 5411 } 5412 } else if (!isRelational && 5413 (LCanPointeeTy->isVoidType() || RCanPointeeTy->isVoidType())) { 5414 // Valid unless comparison between non-null pointer and function pointer 5415 if ((LCanPointeeTy->isFunctionType() || RCanPointeeTy->isFunctionType()) 5416 && !LHSIsNull && !RHSIsNull) { 5417 Diag(Loc, diag::ext_typecheck_comparison_of_fptr_to_void) 5418 << lType << rType << lex->getSourceRange() << rex->getSourceRange(); 5419 } 5420 } else { 5421 // Invalid 5422 Diag(Loc, diag::ext_typecheck_comparison_of_distinct_pointers) 5423 << lType << rType << lex->getSourceRange() << rex->getSourceRange(); 5424 } 5425 if (LCanPointeeTy != RCanPointeeTy) 5426 ImpCastExprToType(rex, lType, CastExpr::CK_BitCast); 5427 return ResultTy; 5428 } 5429 5430 if (getLangOptions().CPlusPlus) { 5431 // Comparison of pointers with null pointer constants and equality 5432 // comparisons of member pointers to null pointer constants. 5433 if (RHSIsNull && 5434 (lType->isPointerType() || 5435 (!isRelational && lType->isMemberPointerType()))) { 5436 ImpCastExprToType(rex, lType, CastExpr::CK_NullToMemberPointer); 5437 return ResultTy; 5438 } 5439 if (LHSIsNull && 5440 (rType->isPointerType() || 5441 (!isRelational && rType->isMemberPointerType()))) { 5442 ImpCastExprToType(lex, rType, CastExpr::CK_NullToMemberPointer); 5443 return ResultTy; 5444 } 5445 5446 // Comparison of member pointers. 5447 if (!isRelational && 5448 lType->isMemberPointerType() && rType->isMemberPointerType()) { 5449 // C++ [expr.eq]p2: 5450 // In addition, pointers to members can be compared, or a pointer to 5451 // member and a null pointer constant. Pointer to member conversions 5452 // (4.11) and qualification conversions (4.4) are performed to bring 5453 // them to a common type. If one operand is a null pointer constant, 5454 // the common type is the type of the other operand. Otherwise, the 5455 // common type is a pointer to member type similar (4.4) to the type 5456 // of one of the operands, with a cv-qualification signature (4.4) 5457 // that is the union of the cv-qualification signatures of the operand 5458 // types. 5459 bool NonStandardCompositeType = false; 5460 QualType T = FindCompositePointerType(Loc, lex, rex, 5461 isSFINAEContext()? 0 : &NonStandardCompositeType); 5462 if (T.isNull()) { 5463 Diag(Loc, diag::err_typecheck_comparison_of_distinct_pointers) 5464 << lType << rType << lex->getSourceRange() << rex->getSourceRange(); 5465 return QualType(); 5466 } else if (NonStandardCompositeType) { 5467 Diag(Loc, 5468 diag::ext_typecheck_comparison_of_distinct_pointers_nonstandard) 5469 << lType << rType << T 5470 << lex->getSourceRange() << rex->getSourceRange(); 5471 } 5472 5473 ImpCastExprToType(lex, T, CastExpr::CK_BitCast); 5474 ImpCastExprToType(rex, T, CastExpr::CK_BitCast); 5475 return ResultTy; 5476 } 5477 5478 // Comparison of nullptr_t with itself. 5479 if (lType->isNullPtrType() && rType->isNullPtrType()) 5480 return ResultTy; 5481 } 5482 5483 // Handle block pointer types. 5484 if (!isRelational && lType->isBlockPointerType() && rType->isBlockPointerType()) { 5485 QualType lpointee = lType->getAs<BlockPointerType>()->getPointeeType(); 5486 QualType rpointee = rType->getAs<BlockPointerType>()->getPointeeType(); 5487 5488 if (!LHSIsNull && !RHSIsNull && 5489 !Context.typesAreCompatible(lpointee, rpointee)) { 5490 Diag(Loc, diag::err_typecheck_comparison_of_distinct_blocks) 5491 << lType << rType << lex->getSourceRange() << rex->getSourceRange(); 5492 } 5493 ImpCastExprToType(rex, lType, CastExpr::CK_BitCast); 5494 return ResultTy; 5495 } 5496 // Allow block pointers to be compared with null pointer constants. 5497 if (!isRelational 5498 && ((lType->isBlockPointerType() && rType->isPointerType()) 5499 || (lType->isPointerType() && rType->isBlockPointerType()))) { 5500 if (!LHSIsNull && !RHSIsNull) { 5501 if (!((rType->isPointerType() && rType->getAs<PointerType>() 5502 ->getPointeeType()->isVoidType()) 5503 || (lType->isPointerType() && lType->getAs<PointerType>() 5504 ->getPointeeType()->isVoidType()))) 5505 Diag(Loc, diag::err_typecheck_comparison_of_distinct_blocks) 5506 << lType << rType << lex->getSourceRange() << rex->getSourceRange(); 5507 } 5508 ImpCastExprToType(rex, lType, CastExpr::CK_BitCast); 5509 return ResultTy; 5510 } 5511 5512 if ((lType->isObjCObjectPointerType() || rType->isObjCObjectPointerType())) { 5513 if (lType->isPointerType() || rType->isPointerType()) { 5514 const PointerType *LPT = lType->getAs<PointerType>(); 5515 const PointerType *RPT = rType->getAs<PointerType>(); 5516 bool LPtrToVoid = LPT ? 5517 Context.getCanonicalType(LPT->getPointeeType())->isVoidType() : false; 5518 bool RPtrToVoid = RPT ? 5519 Context.getCanonicalType(RPT->getPointeeType())->isVoidType() : false; 5520 5521 if (!LPtrToVoid && !RPtrToVoid && 5522 !Context.typesAreCompatible(lType, rType)) { 5523 Diag(Loc, diag::ext_typecheck_comparison_of_distinct_pointers) 5524 << lType << rType << lex->getSourceRange() << rex->getSourceRange(); 5525 } 5526 ImpCastExprToType(rex, lType, CastExpr::CK_BitCast); 5527 return ResultTy; 5528 } 5529 if (lType->isObjCObjectPointerType() && rType->isObjCObjectPointerType()) { 5530 if (!Context.areComparableObjCPointerTypes(lType, rType)) 5531 Diag(Loc, diag::ext_typecheck_comparison_of_distinct_pointers) 5532 << lType << rType << lex->getSourceRange() << rex->getSourceRange(); 5533 ImpCastExprToType(rex, lType, CastExpr::CK_BitCast); 5534 return ResultTy; 5535 } 5536 } 5537 if (lType->isAnyPointerType() && rType->isIntegerType()) { 5538 unsigned DiagID = 0; 5539 if (RHSIsNull) { 5540 if (isRelational) 5541 DiagID = diag::ext_typecheck_ordered_comparison_of_pointer_and_zero; 5542 } else if (isRelational) 5543 DiagID = diag::ext_typecheck_ordered_comparison_of_pointer_integer; 5544 else 5545 DiagID = diag::ext_typecheck_comparison_of_pointer_integer; 5546 5547 if (DiagID) { 5548 Diag(Loc, DiagID) 5549 << lType << rType << lex->getSourceRange() << rex->getSourceRange(); 5550 } 5551 ImpCastExprToType(rex, lType, CastExpr::CK_IntegralToPointer); 5552 return ResultTy; 5553 } 5554 if (lType->isIntegerType() && rType->isAnyPointerType()) { 5555 unsigned DiagID = 0; 5556 if (LHSIsNull) { 5557 if (isRelational) 5558 DiagID = diag::ext_typecheck_ordered_comparison_of_pointer_and_zero; 5559 } else if (isRelational) 5560 DiagID = diag::ext_typecheck_ordered_comparison_of_pointer_integer; 5561 else 5562 DiagID = diag::ext_typecheck_comparison_of_pointer_integer; 5563 5564 if (DiagID) { 5565 Diag(Loc, DiagID) 5566 << lType << rType << lex->getSourceRange() << rex->getSourceRange(); 5567 } 5568 ImpCastExprToType(lex, rType, CastExpr::CK_IntegralToPointer); 5569 return ResultTy; 5570 } 5571 // Handle block pointers. 5572 if (!isRelational && RHSIsNull 5573 && lType->isBlockPointerType() && rType->isIntegerType()) { 5574 ImpCastExprToType(rex, lType, CastExpr::CK_IntegralToPointer); 5575 return ResultTy; 5576 } 5577 if (!isRelational && LHSIsNull 5578 && lType->isIntegerType() && rType->isBlockPointerType()) { 5579 ImpCastExprToType(lex, rType, CastExpr::CK_IntegralToPointer); 5580 return ResultTy; 5581 } 5582 return InvalidOperands(Loc, lex, rex); 5583} 5584 5585/// CheckVectorCompareOperands - vector comparisons are a clang extension that 5586/// operates on extended vector types. Instead of producing an IntTy result, 5587/// like a scalar comparison, a vector comparison produces a vector of integer 5588/// types. 5589QualType Sema::CheckVectorCompareOperands(Expr *&lex, Expr *&rex, 5590 SourceLocation Loc, 5591 bool isRelational) { 5592 // Check to make sure we're operating on vectors of the same type and width, 5593 // Allowing one side to be a scalar of element type. 5594 QualType vType = CheckVectorOperands(Loc, lex, rex); 5595 if (vType.isNull()) 5596 return vType; 5597 5598 QualType lType = lex->getType(); 5599 QualType rType = rex->getType(); 5600 5601 // For non-floating point types, check for self-comparisons of the form 5602 // x == x, x != x, x < x, etc. These always evaluate to a constant, and 5603 // often indicate logic errors in the program. 5604 if (!lType->isFloatingType()) { 5605 if (DeclRefExpr* DRL = dyn_cast<DeclRefExpr>(lex->IgnoreParens())) 5606 if (DeclRefExpr* DRR = dyn_cast<DeclRefExpr>(rex->IgnoreParens())) 5607 if (DRL->getDecl() == DRR->getDecl()) 5608 DiagRuntimeBehavior(Loc, PDiag(diag::warn_selfcomparison)); 5609 } 5610 5611 // Check for comparisons of floating point operands using != and ==. 5612 if (!isRelational && lType->isFloatingType()) { 5613 assert (rType->isFloatingType()); 5614 CheckFloatComparison(Loc,lex,rex); 5615 } 5616 5617 // Return the type for the comparison, which is the same as vector type for 5618 // integer vectors, or an integer type of identical size and number of 5619 // elements for floating point vectors. 5620 if (lType->isIntegerType()) 5621 return lType; 5622 5623 const VectorType *VTy = lType->getAs<VectorType>(); 5624 unsigned TypeSize = Context.getTypeSize(VTy->getElementType()); 5625 if (TypeSize == Context.getTypeSize(Context.IntTy)) 5626 return Context.getExtVectorType(Context.IntTy, VTy->getNumElements()); 5627 if (TypeSize == Context.getTypeSize(Context.LongTy)) 5628 return Context.getExtVectorType(Context.LongTy, VTy->getNumElements()); 5629 5630 assert(TypeSize == Context.getTypeSize(Context.LongLongTy) && 5631 "Unhandled vector element size in vector compare"); 5632 return Context.getExtVectorType(Context.LongLongTy, VTy->getNumElements()); 5633} 5634 5635inline QualType Sema::CheckBitwiseOperands( 5636 Expr *&lex, Expr *&rex, SourceLocation Loc, bool isCompAssign) { 5637 if (lex->getType()->isVectorType() || rex->getType()->isVectorType()) 5638 return CheckVectorOperands(Loc, lex, rex); 5639 5640 QualType compType = UsualArithmeticConversions(lex, rex, isCompAssign); 5641 5642 if (lex->getType()->isIntegerType() && rex->getType()->isIntegerType()) 5643 return compType; 5644 return InvalidOperands(Loc, lex, rex); 5645} 5646 5647inline QualType Sema::CheckLogicalOperands( // C99 6.5.[13,14] 5648 Expr *&lex, Expr *&rex, SourceLocation Loc) { 5649 if (!Context.getLangOptions().CPlusPlus) { 5650 UsualUnaryConversions(lex); 5651 UsualUnaryConversions(rex); 5652 5653 if (!lex->getType()->isScalarType() || !rex->getType()->isScalarType()) 5654 return InvalidOperands(Loc, lex, rex); 5655 5656 return Context.IntTy; 5657 } 5658 5659 // C++ [expr.log.and]p1 5660 // C++ [expr.log.or]p1 5661 // The operands are both implicitly converted to type bool (clause 4). 5662 StandardConversionSequence LHS; 5663 if (!IsStandardConversion(lex, Context.BoolTy, 5664 /*InOverloadResolution=*/false, LHS)) 5665 return InvalidOperands(Loc, lex, rex); 5666 5667 if (PerformImplicitConversion(lex, Context.BoolTy, LHS, 5668 AA_Passing, /*IgnoreBaseAccess=*/false)) 5669 return InvalidOperands(Loc, lex, rex); 5670 5671 StandardConversionSequence RHS; 5672 if (!IsStandardConversion(rex, Context.BoolTy, 5673 /*InOverloadResolution=*/false, RHS)) 5674 return InvalidOperands(Loc, lex, rex); 5675 5676 if (PerformImplicitConversion(rex, Context.BoolTy, RHS, 5677 AA_Passing, /*IgnoreBaseAccess=*/false)) 5678 return InvalidOperands(Loc, lex, rex); 5679 5680 // C++ [expr.log.and]p2 5681 // C++ [expr.log.or]p2 5682 // The result is a bool. 5683 return Context.BoolTy; 5684} 5685 5686/// IsReadonlyProperty - Verify that otherwise a valid l-value expression 5687/// is a read-only property; return true if so. A readonly property expression 5688/// depends on various declarations and thus must be treated specially. 5689/// 5690static bool IsReadonlyProperty(Expr *E, Sema &S) { 5691 if (E->getStmtClass() == Expr::ObjCPropertyRefExprClass) { 5692 const ObjCPropertyRefExpr* PropExpr = cast<ObjCPropertyRefExpr>(E); 5693 if (ObjCPropertyDecl *PDecl = PropExpr->getProperty()) { 5694 QualType BaseType = PropExpr->getBase()->getType(); 5695 if (const ObjCObjectPointerType *OPT = 5696 BaseType->getAsObjCInterfacePointerType()) 5697 if (ObjCInterfaceDecl *IFace = OPT->getInterfaceDecl()) 5698 if (S.isPropertyReadonly(PDecl, IFace)) 5699 return true; 5700 } 5701 } 5702 return false; 5703} 5704 5705/// CheckForModifiableLvalue - Verify that E is a modifiable lvalue. If not, 5706/// emit an error and return true. If so, return false. 5707static bool CheckForModifiableLvalue(Expr *E, SourceLocation Loc, Sema &S) { 5708 SourceLocation OrigLoc = Loc; 5709 Expr::isModifiableLvalueResult IsLV = E->isModifiableLvalue(S.Context, 5710 &Loc); 5711 if (IsLV == Expr::MLV_Valid && IsReadonlyProperty(E, S)) 5712 IsLV = Expr::MLV_ReadonlyProperty; 5713 if (IsLV == Expr::MLV_Valid) 5714 return false; 5715 5716 unsigned Diag = 0; 5717 bool NeedType = false; 5718 switch (IsLV) { // C99 6.5.16p2 5719 case Expr::MLV_ConstQualified: Diag = diag::err_typecheck_assign_const; break; 5720 case Expr::MLV_ArrayType: 5721 Diag = diag::err_typecheck_array_not_modifiable_lvalue; 5722 NeedType = true; 5723 break; 5724 case Expr::MLV_NotObjectType: 5725 Diag = diag::err_typecheck_non_object_not_modifiable_lvalue; 5726 NeedType = true; 5727 break; 5728 case Expr::MLV_LValueCast: 5729 Diag = diag::err_typecheck_lvalue_casts_not_supported; 5730 break; 5731 case Expr::MLV_Valid: 5732 llvm_unreachable("did not take early return for MLV_Valid"); 5733 case Expr::MLV_InvalidExpression: 5734 case Expr::MLV_MemberFunction: 5735 case Expr::MLV_ClassTemporary: 5736 Diag = diag::err_typecheck_expression_not_modifiable_lvalue; 5737 break; 5738 case Expr::MLV_IncompleteType: 5739 case Expr::MLV_IncompleteVoidType: 5740 return S.RequireCompleteType(Loc, E->getType(), 5741 S.PDiag(diag::err_typecheck_incomplete_type_not_modifiable_lvalue) 5742 << E->getSourceRange()); 5743 case Expr::MLV_DuplicateVectorComponents: 5744 Diag = diag::err_typecheck_duplicate_vector_components_not_mlvalue; 5745 break; 5746 case Expr::MLV_NotBlockQualified: 5747 Diag = diag::err_block_decl_ref_not_modifiable_lvalue; 5748 break; 5749 case Expr::MLV_ReadonlyProperty: 5750 Diag = diag::error_readonly_property_assignment; 5751 break; 5752 case Expr::MLV_NoSetterProperty: 5753 Diag = diag::error_nosetter_property_assignment; 5754 break; 5755 case Expr::MLV_SubObjCPropertySetting: 5756 Diag = diag::error_no_subobject_property_setting; 5757 break; 5758 } 5759 5760 SourceRange Assign; 5761 if (Loc != OrigLoc) 5762 Assign = SourceRange(OrigLoc, OrigLoc); 5763 if (NeedType) 5764 S.Diag(Loc, Diag) << E->getType() << E->getSourceRange() << Assign; 5765 else 5766 S.Diag(Loc, Diag) << E->getSourceRange() << Assign; 5767 return true; 5768} 5769 5770 5771 5772// C99 6.5.16.1 5773QualType Sema::CheckAssignmentOperands(Expr *LHS, Expr *&RHS, 5774 SourceLocation Loc, 5775 QualType CompoundType) { 5776 // Verify that LHS is a modifiable lvalue, and emit error if not. 5777 if (CheckForModifiableLvalue(LHS, Loc, *this)) 5778 return QualType(); 5779 5780 QualType LHSType = LHS->getType(); 5781 QualType RHSType = CompoundType.isNull() ? RHS->getType() : CompoundType; 5782 5783 AssignConvertType ConvTy; 5784 if (CompoundType.isNull()) { 5785 // Simple assignment "x = y". 5786 ConvTy = CheckSingleAssignmentConstraints(LHSType, RHS); 5787 // Special case of NSObject attributes on c-style pointer types. 5788 if (ConvTy == IncompatiblePointer && 5789 ((Context.isObjCNSObjectType(LHSType) && 5790 RHSType->isObjCObjectPointerType()) || 5791 (Context.isObjCNSObjectType(RHSType) && 5792 LHSType->isObjCObjectPointerType()))) 5793 ConvTy = Compatible; 5794 5795 // If the RHS is a unary plus or minus, check to see if they = and + are 5796 // right next to each other. If so, the user may have typo'd "x =+ 4" 5797 // instead of "x += 4". 5798 Expr *RHSCheck = RHS; 5799 if (ImplicitCastExpr *ICE = dyn_cast<ImplicitCastExpr>(RHSCheck)) 5800 RHSCheck = ICE->getSubExpr(); 5801 if (UnaryOperator *UO = dyn_cast<UnaryOperator>(RHSCheck)) { 5802 if ((UO->getOpcode() == UnaryOperator::Plus || 5803 UO->getOpcode() == UnaryOperator::Minus) && 5804 Loc.isFileID() && UO->getOperatorLoc().isFileID() && 5805 // Only if the two operators are exactly adjacent. 5806 Loc.getFileLocWithOffset(1) == UO->getOperatorLoc() && 5807 // And there is a space or other character before the subexpr of the 5808 // unary +/-. We don't want to warn on "x=-1". 5809 Loc.getFileLocWithOffset(2) != UO->getSubExpr()->getLocStart() && 5810 UO->getSubExpr()->getLocStart().isFileID()) { 5811 Diag(Loc, diag::warn_not_compound_assign) 5812 << (UO->getOpcode() == UnaryOperator::Plus ? "+" : "-") 5813 << SourceRange(UO->getOperatorLoc(), UO->getOperatorLoc()); 5814 } 5815 } 5816 } else { 5817 // Compound assignment "x += y" 5818 ConvTy = CheckAssignmentConstraints(LHSType, RHSType); 5819 } 5820 5821 if (DiagnoseAssignmentResult(ConvTy, Loc, LHSType, RHSType, 5822 RHS, AA_Assigning)) 5823 return QualType(); 5824 5825 // C99 6.5.16p3: The type of an assignment expression is the type of the 5826 // left operand unless the left operand has qualified type, in which case 5827 // it is the unqualified version of the type of the left operand. 5828 // C99 6.5.16.1p2: In simple assignment, the value of the right operand 5829 // is converted to the type of the assignment expression (above). 5830 // C++ 5.17p1: the type of the assignment expression is that of its left 5831 // operand. 5832 return LHSType.getUnqualifiedType(); 5833} 5834 5835// C99 6.5.17 5836QualType Sema::CheckCommaOperands(Expr *LHS, Expr *&RHS, SourceLocation Loc) { 5837 // Comma performs lvalue conversion (C99 6.3.2.1), but not unary conversions. 5838 // C++ does not perform this conversion (C++ [expr.comma]p1). 5839 if (!getLangOptions().CPlusPlus) 5840 DefaultFunctionArrayLvalueConversion(RHS); 5841 5842 // FIXME: Check that RHS type is complete in C mode (it's legal for it to be 5843 // incomplete in C++). 5844 5845 return RHS->getType(); 5846} 5847 5848/// CheckIncrementDecrementOperand - unlike most "Check" methods, this routine 5849/// doesn't need to call UsualUnaryConversions or UsualArithmeticConversions. 5850QualType Sema::CheckIncrementDecrementOperand(Expr *Op, SourceLocation OpLoc, 5851 bool isInc, bool isPrefix) { 5852 if (Op->isTypeDependent()) 5853 return Context.DependentTy; 5854 5855 QualType ResType = Op->getType(); 5856 assert(!ResType.isNull() && "no type for increment/decrement expression"); 5857 5858 if (getLangOptions().CPlusPlus && ResType->isBooleanType()) { 5859 // Decrement of bool is not allowed. 5860 if (!isInc) { 5861 Diag(OpLoc, diag::err_decrement_bool) << Op->getSourceRange(); 5862 return QualType(); 5863 } 5864 // Increment of bool sets it to true, but is deprecated. 5865 Diag(OpLoc, diag::warn_increment_bool) << Op->getSourceRange(); 5866 } else if (ResType->isRealType()) { 5867 // OK! 5868 } else if (ResType->isAnyPointerType()) { 5869 QualType PointeeTy = ResType->getPointeeType(); 5870 5871 // C99 6.5.2.4p2, 6.5.6p2 5872 if (PointeeTy->isVoidType()) { 5873 if (getLangOptions().CPlusPlus) { 5874 Diag(OpLoc, diag::err_typecheck_pointer_arith_void_type) 5875 << Op->getSourceRange(); 5876 return QualType(); 5877 } 5878 5879 // Pointer to void is a GNU extension in C. 5880 Diag(OpLoc, diag::ext_gnu_void_ptr) << Op->getSourceRange(); 5881 } else if (PointeeTy->isFunctionType()) { 5882 if (getLangOptions().CPlusPlus) { 5883 Diag(OpLoc, diag::err_typecheck_pointer_arith_function_type) 5884 << Op->getType() << Op->getSourceRange(); 5885 return QualType(); 5886 } 5887 5888 Diag(OpLoc, diag::ext_gnu_ptr_func_arith) 5889 << ResType << Op->getSourceRange(); 5890 } else if (RequireCompleteType(OpLoc, PointeeTy, 5891 PDiag(diag::err_typecheck_arithmetic_incomplete_type) 5892 << Op->getSourceRange() 5893 << ResType)) 5894 return QualType(); 5895 // Diagnose bad cases where we step over interface counts. 5896 else if (PointeeTy->isObjCObjectType() && LangOpts.ObjCNonFragileABI) { 5897 Diag(OpLoc, diag::err_arithmetic_nonfragile_interface) 5898 << PointeeTy << Op->getSourceRange(); 5899 return QualType(); 5900 } 5901 } else if (ResType->isAnyComplexType()) { 5902 // C99 does not support ++/-- on complex types, we allow as an extension. 5903 Diag(OpLoc, diag::ext_integer_increment_complex) 5904 << ResType << Op->getSourceRange(); 5905 } else { 5906 Diag(OpLoc, diag::err_typecheck_illegal_increment_decrement) 5907 << ResType << int(isInc) << Op->getSourceRange(); 5908 return QualType(); 5909 } 5910 // At this point, we know we have a real, complex or pointer type. 5911 // Now make sure the operand is a modifiable lvalue. 5912 if (CheckForModifiableLvalue(Op, OpLoc, *this)) 5913 return QualType(); 5914 // In C++, a prefix increment is the same type as the operand. Otherwise 5915 // (in C or with postfix), the increment is the unqualified type of the 5916 // operand. 5917 return isPrefix && getLangOptions().CPlusPlus 5918 ? ResType : ResType.getUnqualifiedType(); 5919} 5920 5921/// getPrimaryDecl - Helper function for CheckAddressOfOperand(). 5922/// This routine allows us to typecheck complex/recursive expressions 5923/// where the declaration is needed for type checking. We only need to 5924/// handle cases when the expression references a function designator 5925/// or is an lvalue. Here are some examples: 5926/// - &(x) => x 5927/// - &*****f => f for f a function designator. 5928/// - &s.xx => s 5929/// - &s.zz[1].yy -> s, if zz is an array 5930/// - *(x + 1) -> x, if x is an array 5931/// - &"123"[2] -> 0 5932/// - & __real__ x -> x 5933static NamedDecl *getPrimaryDecl(Expr *E) { 5934 switch (E->getStmtClass()) { 5935 case Stmt::DeclRefExprClass: 5936 return cast<DeclRefExpr>(E)->getDecl(); 5937 case Stmt::MemberExprClass: 5938 // If this is an arrow operator, the address is an offset from 5939 // the base's value, so the object the base refers to is 5940 // irrelevant. 5941 if (cast<MemberExpr>(E)->isArrow()) 5942 return 0; 5943 // Otherwise, the expression refers to a part of the base 5944 return getPrimaryDecl(cast<MemberExpr>(E)->getBase()); 5945 case Stmt::ArraySubscriptExprClass: { 5946 // FIXME: This code shouldn't be necessary! We should catch the implicit 5947 // promotion of register arrays earlier. 5948 Expr* Base = cast<ArraySubscriptExpr>(E)->getBase(); 5949 if (ImplicitCastExpr* ICE = dyn_cast<ImplicitCastExpr>(Base)) { 5950 if (ICE->getSubExpr()->getType()->isArrayType()) 5951 return getPrimaryDecl(ICE->getSubExpr()); 5952 } 5953 return 0; 5954 } 5955 case Stmt::UnaryOperatorClass: { 5956 UnaryOperator *UO = cast<UnaryOperator>(E); 5957 5958 switch(UO->getOpcode()) { 5959 case UnaryOperator::Real: 5960 case UnaryOperator::Imag: 5961 case UnaryOperator::Extension: 5962 return getPrimaryDecl(UO->getSubExpr()); 5963 default: 5964 return 0; 5965 } 5966 } 5967 case Stmt::ParenExprClass: 5968 return getPrimaryDecl(cast<ParenExpr>(E)->getSubExpr()); 5969 case Stmt::ImplicitCastExprClass: 5970 // If the result of an implicit cast is an l-value, we care about 5971 // the sub-expression; otherwise, the result here doesn't matter. 5972 return getPrimaryDecl(cast<ImplicitCastExpr>(E)->getSubExpr()); 5973 default: 5974 return 0; 5975 } 5976} 5977 5978/// CheckAddressOfOperand - The operand of & must be either a function 5979/// designator or an lvalue designating an object. If it is an lvalue, the 5980/// object cannot be declared with storage class register or be a bit field. 5981/// Note: The usual conversions are *not* applied to the operand of the & 5982/// operator (C99 6.3.2.1p[2-4]), and its result is never an lvalue. 5983/// In C++, the operand might be an overloaded function name, in which case 5984/// we allow the '&' but retain the overloaded-function type. 5985QualType Sema::CheckAddressOfOperand(Expr *op, SourceLocation OpLoc) { 5986 // Make sure to ignore parentheses in subsequent checks 5987 op = op->IgnoreParens(); 5988 5989 if (op->isTypeDependent()) 5990 return Context.DependentTy; 5991 5992 if (getLangOptions().C99) { 5993 // Implement C99-only parts of addressof rules. 5994 if (UnaryOperator* uOp = dyn_cast<UnaryOperator>(op)) { 5995 if (uOp->getOpcode() == UnaryOperator::Deref) 5996 // Per C99 6.5.3.2, the address of a deref always returns a valid result 5997 // (assuming the deref expression is valid). 5998 return uOp->getSubExpr()->getType(); 5999 } 6000 // Technically, there should be a check for array subscript 6001 // expressions here, but the result of one is always an lvalue anyway. 6002 } 6003 NamedDecl *dcl = getPrimaryDecl(op); 6004 Expr::isLvalueResult lval = op->isLvalue(Context); 6005 6006 MemberExpr *ME = dyn_cast<MemberExpr>(op); 6007 if (lval == Expr::LV_MemberFunction && ME && 6008 isa<CXXMethodDecl>(ME->getMemberDecl())) { 6009 ValueDecl *dcl = cast<MemberExpr>(op)->getMemberDecl(); 6010 // &f where f is a member of the current object, or &o.f, or &p->f 6011 // All these are not allowed, and we need to catch them before the dcl 6012 // branch of the if, below. 6013 Diag(OpLoc, diag::err_unqualified_pointer_member_function) 6014 << dcl; 6015 // FIXME: Improve this diagnostic and provide a fixit. 6016 6017 // Now recover by acting as if the function had been accessed qualified. 6018 return Context.getMemberPointerType(op->getType(), 6019 Context.getTypeDeclType(cast<RecordDecl>(dcl->getDeclContext())) 6020 .getTypePtr()); 6021 } else if (lval == Expr::LV_ClassTemporary) { 6022 Diag(OpLoc, isSFINAEContext()? diag::err_typecheck_addrof_class_temporary 6023 : diag::ext_typecheck_addrof_class_temporary) 6024 << op->getType() << op->getSourceRange(); 6025 if (isSFINAEContext()) 6026 return QualType(); 6027 } else if (lval != Expr::LV_Valid && lval != Expr::LV_IncompleteVoidType) { 6028 // C99 6.5.3.2p1 6029 // The operand must be either an l-value or a function designator 6030 if (!op->getType()->isFunctionType()) { 6031 // FIXME: emit more specific diag... 6032 Diag(OpLoc, diag::err_typecheck_invalid_lvalue_addrof) 6033 << op->getSourceRange(); 6034 return QualType(); 6035 } 6036 } else if (op->getBitField()) { // C99 6.5.3.2p1 6037 // The operand cannot be a bit-field 6038 Diag(OpLoc, diag::err_typecheck_address_of) 6039 << "bit-field" << op->getSourceRange(); 6040 return QualType(); 6041 } else if (op->refersToVectorElement()) { 6042 // The operand cannot be an element of a vector 6043 Diag(OpLoc, diag::err_typecheck_address_of) 6044 << "vector element" << op->getSourceRange(); 6045 return QualType(); 6046 } else if (isa<ObjCPropertyRefExpr>(op)) { 6047 // cannot take address of a property expression. 6048 Diag(OpLoc, diag::err_typecheck_address_of) 6049 << "property expression" << op->getSourceRange(); 6050 return QualType(); 6051 } else if (ConditionalOperator *CO = dyn_cast<ConditionalOperator>(op)) { 6052 // FIXME: Can LHS ever be null here? 6053 if (!CheckAddressOfOperand(CO->getTrueExpr(), OpLoc).isNull()) 6054 return CheckAddressOfOperand(CO->getFalseExpr(), OpLoc); 6055 } else if (isa<UnresolvedLookupExpr>(op)) { 6056 return Context.OverloadTy; 6057 } else if (dcl) { // C99 6.5.3.2p1 6058 // We have an lvalue with a decl. Make sure the decl is not declared 6059 // with the register storage-class specifier. 6060 if (const VarDecl *vd = dyn_cast<VarDecl>(dcl)) { 6061 if (vd->getStorageClass() == VarDecl::Register) { 6062 Diag(OpLoc, diag::err_typecheck_address_of) 6063 << "register variable" << op->getSourceRange(); 6064 return QualType(); 6065 } 6066 } else if (isa<FunctionTemplateDecl>(dcl)) { 6067 return Context.OverloadTy; 6068 } else if (FieldDecl *FD = dyn_cast<FieldDecl>(dcl)) { 6069 // Okay: we can take the address of a field. 6070 // Could be a pointer to member, though, if there is an explicit 6071 // scope qualifier for the class. 6072 if (isa<DeclRefExpr>(op) && cast<DeclRefExpr>(op)->getQualifier()) { 6073 DeclContext *Ctx = dcl->getDeclContext(); 6074 if (Ctx && Ctx->isRecord()) { 6075 if (FD->getType()->isReferenceType()) { 6076 Diag(OpLoc, 6077 diag::err_cannot_form_pointer_to_member_of_reference_type) 6078 << FD->getDeclName() << FD->getType(); 6079 return QualType(); 6080 } 6081 6082 return Context.getMemberPointerType(op->getType(), 6083 Context.getTypeDeclType(cast<RecordDecl>(Ctx)).getTypePtr()); 6084 } 6085 } 6086 } else if (CXXMethodDecl *MD = dyn_cast<CXXMethodDecl>(dcl)) { 6087 // Okay: we can take the address of a function. 6088 // As above. 6089 if (isa<DeclRefExpr>(op) && cast<DeclRefExpr>(op)->getQualifier() && 6090 MD->isInstance()) 6091 return Context.getMemberPointerType(op->getType(), 6092 Context.getTypeDeclType(MD->getParent()).getTypePtr()); 6093 } else if (!isa<FunctionDecl>(dcl)) 6094 assert(0 && "Unknown/unexpected decl type"); 6095 } 6096 6097 if (lval == Expr::LV_IncompleteVoidType) { 6098 // Taking the address of a void variable is technically illegal, but we 6099 // allow it in cases which are otherwise valid. 6100 // Example: "extern void x; void* y = &x;". 6101 Diag(OpLoc, diag::ext_typecheck_addrof_void) << op->getSourceRange(); 6102 } 6103 6104 // If the operand has type "type", the result has type "pointer to type". 6105 return Context.getPointerType(op->getType()); 6106} 6107 6108QualType Sema::CheckIndirectionOperand(Expr *Op, SourceLocation OpLoc) { 6109 if (Op->isTypeDependent()) 6110 return Context.DependentTy; 6111 6112 UsualUnaryConversions(Op); 6113 QualType Ty = Op->getType(); 6114 6115 // Note that per both C89 and C99, this is always legal, even if ptype is an 6116 // incomplete type or void. It would be possible to warn about dereferencing 6117 // a void pointer, but it's completely well-defined, and such a warning is 6118 // unlikely to catch any mistakes. 6119 if (const PointerType *PT = Ty->getAs<PointerType>()) 6120 return PT->getPointeeType(); 6121 6122 if (const ObjCObjectPointerType *OPT = Ty->getAs<ObjCObjectPointerType>()) 6123 return OPT->getPointeeType(); 6124 6125 Diag(OpLoc, diag::err_typecheck_indirection_requires_pointer) 6126 << Ty << Op->getSourceRange(); 6127 return QualType(); 6128} 6129 6130static inline BinaryOperator::Opcode ConvertTokenKindToBinaryOpcode( 6131 tok::TokenKind Kind) { 6132 BinaryOperator::Opcode Opc; 6133 switch (Kind) { 6134 default: assert(0 && "Unknown binop!"); 6135 case tok::periodstar: Opc = BinaryOperator::PtrMemD; break; 6136 case tok::arrowstar: Opc = BinaryOperator::PtrMemI; break; 6137 case tok::star: Opc = BinaryOperator::Mul; break; 6138 case tok::slash: Opc = BinaryOperator::Div; break; 6139 case tok::percent: Opc = BinaryOperator::Rem; break; 6140 case tok::plus: Opc = BinaryOperator::Add; break; 6141 case tok::minus: Opc = BinaryOperator::Sub; break; 6142 case tok::lessless: Opc = BinaryOperator::Shl; break; 6143 case tok::greatergreater: Opc = BinaryOperator::Shr; break; 6144 case tok::lessequal: Opc = BinaryOperator::LE; break; 6145 case tok::less: Opc = BinaryOperator::LT; break; 6146 case tok::greaterequal: Opc = BinaryOperator::GE; break; 6147 case tok::greater: Opc = BinaryOperator::GT; break; 6148 case tok::exclaimequal: Opc = BinaryOperator::NE; break; 6149 case tok::equalequal: Opc = BinaryOperator::EQ; break; 6150 case tok::amp: Opc = BinaryOperator::And; break; 6151 case tok::caret: Opc = BinaryOperator::Xor; break; 6152 case tok::pipe: Opc = BinaryOperator::Or; break; 6153 case tok::ampamp: Opc = BinaryOperator::LAnd; break; 6154 case tok::pipepipe: Opc = BinaryOperator::LOr; break; 6155 case tok::equal: Opc = BinaryOperator::Assign; break; 6156 case tok::starequal: Opc = BinaryOperator::MulAssign; break; 6157 case tok::slashequal: Opc = BinaryOperator::DivAssign; break; 6158 case tok::percentequal: Opc = BinaryOperator::RemAssign; break; 6159 case tok::plusequal: Opc = BinaryOperator::AddAssign; break; 6160 case tok::minusequal: Opc = BinaryOperator::SubAssign; break; 6161 case tok::lesslessequal: Opc = BinaryOperator::ShlAssign; break; 6162 case tok::greatergreaterequal: Opc = BinaryOperator::ShrAssign; break; 6163 case tok::ampequal: Opc = BinaryOperator::AndAssign; break; 6164 case tok::caretequal: Opc = BinaryOperator::XorAssign; break; 6165 case tok::pipeequal: Opc = BinaryOperator::OrAssign; break; 6166 case tok::comma: Opc = BinaryOperator::Comma; break; 6167 } 6168 return Opc; 6169} 6170 6171static inline UnaryOperator::Opcode ConvertTokenKindToUnaryOpcode( 6172 tok::TokenKind Kind) { 6173 UnaryOperator::Opcode Opc; 6174 switch (Kind) { 6175 default: assert(0 && "Unknown unary op!"); 6176 case tok::plusplus: Opc = UnaryOperator::PreInc; break; 6177 case tok::minusminus: Opc = UnaryOperator::PreDec; break; 6178 case tok::amp: Opc = UnaryOperator::AddrOf; break; 6179 case tok::star: Opc = UnaryOperator::Deref; break; 6180 case tok::plus: Opc = UnaryOperator::Plus; break; 6181 case tok::minus: Opc = UnaryOperator::Minus; break; 6182 case tok::tilde: Opc = UnaryOperator::Not; break; 6183 case tok::exclaim: Opc = UnaryOperator::LNot; break; 6184 case tok::kw___real: Opc = UnaryOperator::Real; break; 6185 case tok::kw___imag: Opc = UnaryOperator::Imag; break; 6186 case tok::kw___extension__: Opc = UnaryOperator::Extension; break; 6187 } 6188 return Opc; 6189} 6190 6191/// CreateBuiltinBinOp - Creates a new built-in binary operation with 6192/// operator @p Opc at location @c TokLoc. This routine only supports 6193/// built-in operations; ActOnBinOp handles overloaded operators. 6194Action::OwningExprResult Sema::CreateBuiltinBinOp(SourceLocation OpLoc, 6195 unsigned Op, 6196 Expr *lhs, Expr *rhs) { 6197 QualType ResultTy; // Result type of the binary operator. 6198 BinaryOperator::Opcode Opc = (BinaryOperator::Opcode)Op; 6199 // The following two variables are used for compound assignment operators 6200 QualType CompLHSTy; // Type of LHS after promotions for computation 6201 QualType CompResultTy; // Type of computation result 6202 6203 switch (Opc) { 6204 case BinaryOperator::Assign: 6205 ResultTy = CheckAssignmentOperands(lhs, rhs, OpLoc, QualType()); 6206 break; 6207 case BinaryOperator::PtrMemD: 6208 case BinaryOperator::PtrMemI: 6209 ResultTy = CheckPointerToMemberOperands(lhs, rhs, OpLoc, 6210 Opc == BinaryOperator::PtrMemI); 6211 break; 6212 case BinaryOperator::Mul: 6213 case BinaryOperator::Div: 6214 ResultTy = CheckMultiplyDivideOperands(lhs, rhs, OpLoc, false, 6215 Opc == BinaryOperator::Div); 6216 break; 6217 case BinaryOperator::Rem: 6218 ResultTy = CheckRemainderOperands(lhs, rhs, OpLoc); 6219 break; 6220 case BinaryOperator::Add: 6221 ResultTy = CheckAdditionOperands(lhs, rhs, OpLoc); 6222 break; 6223 case BinaryOperator::Sub: 6224 ResultTy = CheckSubtractionOperands(lhs, rhs, OpLoc); 6225 break; 6226 case BinaryOperator::Shl: 6227 case BinaryOperator::Shr: 6228 ResultTy = CheckShiftOperands(lhs, rhs, OpLoc); 6229 break; 6230 case BinaryOperator::LE: 6231 case BinaryOperator::LT: 6232 case BinaryOperator::GE: 6233 case BinaryOperator::GT: 6234 ResultTy = CheckCompareOperands(lhs, rhs, OpLoc, Opc, true); 6235 break; 6236 case BinaryOperator::EQ: 6237 case BinaryOperator::NE: 6238 ResultTy = CheckCompareOperands(lhs, rhs, OpLoc, Opc, false); 6239 break; 6240 case BinaryOperator::And: 6241 case BinaryOperator::Xor: 6242 case BinaryOperator::Or: 6243 ResultTy = CheckBitwiseOperands(lhs, rhs, OpLoc); 6244 break; 6245 case BinaryOperator::LAnd: 6246 case BinaryOperator::LOr: 6247 ResultTy = CheckLogicalOperands(lhs, rhs, OpLoc); 6248 break; 6249 case BinaryOperator::MulAssign: 6250 case BinaryOperator::DivAssign: 6251 CompResultTy = CheckMultiplyDivideOperands(lhs, rhs, OpLoc, true, 6252 Opc == BinaryOperator::DivAssign); 6253 CompLHSTy = CompResultTy; 6254 if (!CompResultTy.isNull()) 6255 ResultTy = CheckAssignmentOperands(lhs, rhs, OpLoc, CompResultTy); 6256 break; 6257 case BinaryOperator::RemAssign: 6258 CompResultTy = CheckRemainderOperands(lhs, rhs, OpLoc, true); 6259 CompLHSTy = CompResultTy; 6260 if (!CompResultTy.isNull()) 6261 ResultTy = CheckAssignmentOperands(lhs, rhs, OpLoc, CompResultTy); 6262 break; 6263 case BinaryOperator::AddAssign: 6264 CompResultTy = CheckAdditionOperands(lhs, rhs, OpLoc, &CompLHSTy); 6265 if (!CompResultTy.isNull()) 6266 ResultTy = CheckAssignmentOperands(lhs, rhs, OpLoc, CompResultTy); 6267 break; 6268 case BinaryOperator::SubAssign: 6269 CompResultTy = CheckSubtractionOperands(lhs, rhs, OpLoc, &CompLHSTy); 6270 if (!CompResultTy.isNull()) 6271 ResultTy = CheckAssignmentOperands(lhs, rhs, OpLoc, CompResultTy); 6272 break; 6273 case BinaryOperator::ShlAssign: 6274 case BinaryOperator::ShrAssign: 6275 CompResultTy = CheckShiftOperands(lhs, rhs, OpLoc, true); 6276 CompLHSTy = CompResultTy; 6277 if (!CompResultTy.isNull()) 6278 ResultTy = CheckAssignmentOperands(lhs, rhs, OpLoc, CompResultTy); 6279 break; 6280 case BinaryOperator::AndAssign: 6281 case BinaryOperator::XorAssign: 6282 case BinaryOperator::OrAssign: 6283 CompResultTy = CheckBitwiseOperands(lhs, rhs, OpLoc, true); 6284 CompLHSTy = CompResultTy; 6285 if (!CompResultTy.isNull()) 6286 ResultTy = CheckAssignmentOperands(lhs, rhs, OpLoc, CompResultTy); 6287 break; 6288 case BinaryOperator::Comma: 6289 ResultTy = CheckCommaOperands(lhs, rhs, OpLoc); 6290 break; 6291 } 6292 if (ResultTy.isNull()) 6293 return ExprError(); 6294 if (CompResultTy.isNull()) 6295 return Owned(new (Context) BinaryOperator(lhs, rhs, Opc, ResultTy, OpLoc)); 6296 else 6297 return Owned(new (Context) CompoundAssignOperator(lhs, rhs, Opc, ResultTy, 6298 CompLHSTy, CompResultTy, 6299 OpLoc)); 6300} 6301 6302/// SuggestParentheses - Emit a diagnostic together with a fixit hint that wraps 6303/// ParenRange in parentheses. 6304static void SuggestParentheses(Sema &Self, SourceLocation Loc, 6305 const PartialDiagnostic &PD, 6306 const PartialDiagnostic &FirstNote, 6307 SourceRange FirstParenRange, 6308 const PartialDiagnostic &SecondNote, 6309 SourceRange SecondParenRange) { 6310 Self.Diag(Loc, PD); 6311 6312 if (!FirstNote.getDiagID()) 6313 return; 6314 6315 SourceLocation EndLoc = Self.PP.getLocForEndOfToken(FirstParenRange.getEnd()); 6316 if (!FirstParenRange.getEnd().isFileID() || EndLoc.isInvalid()) { 6317 // We can't display the parentheses, so just return. 6318 return; 6319 } 6320 6321 Self.Diag(Loc, FirstNote) 6322 << FixItHint::CreateInsertion(FirstParenRange.getBegin(), "(") 6323 << FixItHint::CreateInsertion(EndLoc, ")"); 6324 6325 if (!SecondNote.getDiagID()) 6326 return; 6327 6328 EndLoc = Self.PP.getLocForEndOfToken(SecondParenRange.getEnd()); 6329 if (!SecondParenRange.getEnd().isFileID() || EndLoc.isInvalid()) { 6330 // We can't display the parentheses, so just dig the 6331 // warning/error and return. 6332 Self.Diag(Loc, SecondNote); 6333 return; 6334 } 6335 6336 Self.Diag(Loc, SecondNote) 6337 << FixItHint::CreateInsertion(SecondParenRange.getBegin(), "(") 6338 << FixItHint::CreateInsertion(EndLoc, ")"); 6339} 6340 6341/// DiagnoseBitwisePrecedence - Emit a warning when bitwise and comparison 6342/// operators are mixed in a way that suggests that the programmer forgot that 6343/// comparison operators have higher precedence. The most typical example of 6344/// such code is "flags & 0x0020 != 0", which is equivalent to "flags & 1". 6345static void DiagnoseBitwisePrecedence(Sema &Self, BinaryOperator::Opcode Opc, 6346 SourceLocation OpLoc,Expr *lhs,Expr *rhs){ 6347 typedef BinaryOperator BinOp; 6348 BinOp::Opcode lhsopc = static_cast<BinOp::Opcode>(-1), 6349 rhsopc = static_cast<BinOp::Opcode>(-1); 6350 if (BinOp *BO = dyn_cast<BinOp>(lhs)) 6351 lhsopc = BO->getOpcode(); 6352 if (BinOp *BO = dyn_cast<BinOp>(rhs)) 6353 rhsopc = BO->getOpcode(); 6354 6355 // Subs are not binary operators. 6356 if (lhsopc == -1 && rhsopc == -1) 6357 return; 6358 6359 // Bitwise operations are sometimes used as eager logical ops. 6360 // Don't diagnose this. 6361 if ((BinOp::isComparisonOp(lhsopc) || BinOp::isBitwiseOp(lhsopc)) && 6362 (BinOp::isComparisonOp(rhsopc) || BinOp::isBitwiseOp(rhsopc))) 6363 return; 6364 6365 if (BinOp::isComparisonOp(lhsopc)) 6366 SuggestParentheses(Self, OpLoc, 6367 Self.PDiag(diag::warn_precedence_bitwise_rel) 6368 << SourceRange(lhs->getLocStart(), OpLoc) 6369 << BinOp::getOpcodeStr(Opc) << BinOp::getOpcodeStr(lhsopc), 6370 Self.PDiag(diag::note_precedence_bitwise_first) 6371 << BinOp::getOpcodeStr(Opc), 6372 SourceRange(cast<BinOp>(lhs)->getRHS()->getLocStart(), rhs->getLocEnd()), 6373 Self.PDiag(diag::note_precedence_bitwise_silence) 6374 << BinOp::getOpcodeStr(lhsopc), 6375 lhs->getSourceRange()); 6376 else if (BinOp::isComparisonOp(rhsopc)) 6377 SuggestParentheses(Self, OpLoc, 6378 Self.PDiag(diag::warn_precedence_bitwise_rel) 6379 << SourceRange(OpLoc, rhs->getLocEnd()) 6380 << BinOp::getOpcodeStr(Opc) << BinOp::getOpcodeStr(rhsopc), 6381 Self.PDiag(diag::note_precedence_bitwise_first) 6382 << BinOp::getOpcodeStr(Opc), 6383 SourceRange(lhs->getLocEnd(), cast<BinOp>(rhs)->getLHS()->getLocStart()), 6384 Self.PDiag(diag::note_precedence_bitwise_silence) 6385 << BinOp::getOpcodeStr(rhsopc), 6386 rhs->getSourceRange()); 6387} 6388 6389/// DiagnoseBinOpPrecedence - Emit warnings for expressions with tricky 6390/// precedence. This currently diagnoses only "arg1 'bitwise' arg2 'eq' arg3". 6391/// But it could also warn about arg1 && arg2 || arg3, as GCC 4.3+ does. 6392static void DiagnoseBinOpPrecedence(Sema &Self, BinaryOperator::Opcode Opc, 6393 SourceLocation OpLoc, Expr *lhs, Expr *rhs){ 6394 if (BinaryOperator::isBitwiseOp(Opc)) 6395 DiagnoseBitwisePrecedence(Self, Opc, OpLoc, lhs, rhs); 6396} 6397 6398// Binary Operators. 'Tok' is the token for the operator. 6399Action::OwningExprResult Sema::ActOnBinOp(Scope *S, SourceLocation TokLoc, 6400 tok::TokenKind Kind, 6401 ExprArg LHS, ExprArg RHS) { 6402 BinaryOperator::Opcode Opc = ConvertTokenKindToBinaryOpcode(Kind); 6403 Expr *lhs = LHS.takeAs<Expr>(), *rhs = RHS.takeAs<Expr>(); 6404 6405 assert((lhs != 0) && "ActOnBinOp(): missing left expression"); 6406 assert((rhs != 0) && "ActOnBinOp(): missing right expression"); 6407 6408 // Emit warnings for tricky precedence issues, e.g. "bitfield & 0x4 == 0" 6409 DiagnoseBinOpPrecedence(*this, Opc, TokLoc, lhs, rhs); 6410 6411 return BuildBinOp(S, TokLoc, Opc, lhs, rhs); 6412} 6413 6414Action::OwningExprResult Sema::BuildBinOp(Scope *S, SourceLocation OpLoc, 6415 BinaryOperator::Opcode Opc, 6416 Expr *lhs, Expr *rhs) { 6417 if (getLangOptions().CPlusPlus && 6418 (lhs->getType()->isOverloadableType() || 6419 rhs->getType()->isOverloadableType())) { 6420 // Find all of the overloaded operators visible from this 6421 // point. We perform both an operator-name lookup from the local 6422 // scope and an argument-dependent lookup based on the types of 6423 // the arguments. 6424 UnresolvedSet<16> Functions; 6425 OverloadedOperatorKind OverOp = BinaryOperator::getOverloadedOperator(Opc); 6426 if (S && OverOp != OO_None) 6427 LookupOverloadedOperatorName(OverOp, S, lhs->getType(), rhs->getType(), 6428 Functions); 6429 6430 // Build the (potentially-overloaded, potentially-dependent) 6431 // binary operation. 6432 return CreateOverloadedBinOp(OpLoc, Opc, Functions, lhs, rhs); 6433 } 6434 6435 // Build a built-in binary operation. 6436 return CreateBuiltinBinOp(OpLoc, Opc, lhs, rhs); 6437} 6438 6439Action::OwningExprResult Sema::CreateBuiltinUnaryOp(SourceLocation OpLoc, 6440 unsigned OpcIn, 6441 ExprArg InputArg) { 6442 UnaryOperator::Opcode Opc = static_cast<UnaryOperator::Opcode>(OpcIn); 6443 6444 // FIXME: Input is modified below, but InputArg is not updated appropriately. 6445 Expr *Input = (Expr *)InputArg.get(); 6446 QualType resultType; 6447 switch (Opc) { 6448 case UnaryOperator::OffsetOf: 6449 assert(false && "Invalid unary operator"); 6450 break; 6451 6452 case UnaryOperator::PreInc: 6453 case UnaryOperator::PreDec: 6454 case UnaryOperator::PostInc: 6455 case UnaryOperator::PostDec: 6456 resultType = CheckIncrementDecrementOperand(Input, OpLoc, 6457 Opc == UnaryOperator::PreInc || 6458 Opc == UnaryOperator::PostInc, 6459 Opc == UnaryOperator::PreInc || 6460 Opc == UnaryOperator::PreDec); 6461 break; 6462 case UnaryOperator::AddrOf: 6463 resultType = CheckAddressOfOperand(Input, OpLoc); 6464 break; 6465 case UnaryOperator::Deref: 6466 DefaultFunctionArrayLvalueConversion(Input); 6467 resultType = CheckIndirectionOperand(Input, OpLoc); 6468 break; 6469 case UnaryOperator::Plus: 6470 case UnaryOperator::Minus: 6471 UsualUnaryConversions(Input); 6472 resultType = Input->getType(); 6473 if (resultType->isDependentType()) 6474 break; 6475 if (resultType->isArithmeticType()) // C99 6.5.3.3p1 6476 break; 6477 else if (getLangOptions().CPlusPlus && // C++ [expr.unary.op]p6-7 6478 resultType->isEnumeralType()) 6479 break; 6480 else if (getLangOptions().CPlusPlus && // C++ [expr.unary.op]p6 6481 Opc == UnaryOperator::Plus && 6482 resultType->isPointerType()) 6483 break; 6484 6485 return ExprError(Diag(OpLoc, diag::err_typecheck_unary_expr) 6486 << resultType << Input->getSourceRange()); 6487 case UnaryOperator::Not: // bitwise complement 6488 UsualUnaryConversions(Input); 6489 resultType = Input->getType(); 6490 if (resultType->isDependentType()) 6491 break; 6492 // C99 6.5.3.3p1. We allow complex int and float as a GCC extension. 6493 if (resultType->isComplexType() || resultType->isComplexIntegerType()) 6494 // C99 does not support '~' for complex conjugation. 6495 Diag(OpLoc, diag::ext_integer_complement_complex) 6496 << resultType << Input->getSourceRange(); 6497 else if (!resultType->isIntegerType()) 6498 return ExprError(Diag(OpLoc, diag::err_typecheck_unary_expr) 6499 << resultType << Input->getSourceRange()); 6500 break; 6501 case UnaryOperator::LNot: // logical negation 6502 // Unlike +/-/~, integer promotions aren't done here (C99 6.5.3.3p5). 6503 DefaultFunctionArrayLvalueConversion(Input); 6504 resultType = Input->getType(); 6505 if (resultType->isDependentType()) 6506 break; 6507 if (!resultType->isScalarType()) // C99 6.5.3.3p1 6508 return ExprError(Diag(OpLoc, diag::err_typecheck_unary_expr) 6509 << resultType << Input->getSourceRange()); 6510 // LNot always has type int. C99 6.5.3.3p5. 6511 // In C++, it's bool. C++ 5.3.1p8 6512 resultType = getLangOptions().CPlusPlus ? Context.BoolTy : Context.IntTy; 6513 break; 6514 case UnaryOperator::Real: 6515 case UnaryOperator::Imag: 6516 resultType = CheckRealImagOperand(Input, OpLoc, Opc == UnaryOperator::Real); 6517 break; 6518 case UnaryOperator::Extension: 6519 resultType = Input->getType(); 6520 break; 6521 } 6522 if (resultType.isNull()) 6523 return ExprError(); 6524 6525 InputArg.release(); 6526 return Owned(new (Context) UnaryOperator(Input, Opc, resultType, OpLoc)); 6527} 6528 6529Action::OwningExprResult Sema::BuildUnaryOp(Scope *S, SourceLocation OpLoc, 6530 UnaryOperator::Opcode Opc, 6531 ExprArg input) { 6532 Expr *Input = (Expr*)input.get(); 6533 if (getLangOptions().CPlusPlus && Input->getType()->isOverloadableType() && 6534 Opc != UnaryOperator::Extension) { 6535 // Find all of the overloaded operators visible from this 6536 // point. We perform both an operator-name lookup from the local 6537 // scope and an argument-dependent lookup based on the types of 6538 // the arguments. 6539 UnresolvedSet<16> Functions; 6540 OverloadedOperatorKind OverOp = UnaryOperator::getOverloadedOperator(Opc); 6541 if (S && OverOp != OO_None) 6542 LookupOverloadedOperatorName(OverOp, S, Input->getType(), QualType(), 6543 Functions); 6544 6545 return CreateOverloadedUnaryOp(OpLoc, Opc, Functions, move(input)); 6546 } 6547 6548 return CreateBuiltinUnaryOp(OpLoc, Opc, move(input)); 6549} 6550 6551// Unary Operators. 'Tok' is the token for the operator. 6552Action::OwningExprResult Sema::ActOnUnaryOp(Scope *S, SourceLocation OpLoc, 6553 tok::TokenKind Op, ExprArg input) { 6554 return BuildUnaryOp(S, OpLoc, ConvertTokenKindToUnaryOpcode(Op), move(input)); 6555} 6556 6557/// ActOnAddrLabel - Parse the GNU address of label extension: "&&foo". 6558Sema::OwningExprResult Sema::ActOnAddrLabel(SourceLocation OpLoc, 6559 SourceLocation LabLoc, 6560 IdentifierInfo *LabelII) { 6561 // Look up the record for this label identifier. 6562 LabelStmt *&LabelDecl = getLabelMap()[LabelII]; 6563 6564 // If we haven't seen this label yet, create a forward reference. It 6565 // will be validated and/or cleaned up in ActOnFinishFunctionBody. 6566 if (LabelDecl == 0) 6567 LabelDecl = new (Context) LabelStmt(LabLoc, LabelII, 0); 6568 6569 // Create the AST node. The address of a label always has type 'void*'. 6570 return Owned(new (Context) AddrLabelExpr(OpLoc, LabLoc, LabelDecl, 6571 Context.getPointerType(Context.VoidTy))); 6572} 6573 6574Sema::OwningExprResult 6575Sema::ActOnStmtExpr(SourceLocation LPLoc, StmtArg substmt, 6576 SourceLocation RPLoc) { // "({..})" 6577 Stmt *SubStmt = static_cast<Stmt*>(substmt.get()); 6578 assert(SubStmt && isa<CompoundStmt>(SubStmt) && "Invalid action invocation!"); 6579 CompoundStmt *Compound = cast<CompoundStmt>(SubStmt); 6580 6581 bool isFileScope 6582 = (getCurFunctionOrMethodDecl() == 0) && (getCurBlock() == 0); 6583 if (isFileScope) 6584 return ExprError(Diag(LPLoc, diag::err_stmtexpr_file_scope)); 6585 6586 // FIXME: there are a variety of strange constraints to enforce here, for 6587 // example, it is not possible to goto into a stmt expression apparently. 6588 // More semantic analysis is needed. 6589 6590 // If there are sub stmts in the compound stmt, take the type of the last one 6591 // as the type of the stmtexpr. 6592 QualType Ty = Context.VoidTy; 6593 6594 if (!Compound->body_empty()) { 6595 Stmt *LastStmt = Compound->body_back(); 6596 // If LastStmt is a label, skip down through into the body. 6597 while (LabelStmt *Label = dyn_cast<LabelStmt>(LastStmt)) 6598 LastStmt = Label->getSubStmt(); 6599 6600 if (Expr *LastExpr = dyn_cast<Expr>(LastStmt)) 6601 Ty = LastExpr->getType(); 6602 } 6603 6604 // FIXME: Check that expression type is complete/non-abstract; statement 6605 // expressions are not lvalues. 6606 6607 substmt.release(); 6608 return Owned(new (Context) StmtExpr(Compound, Ty, LPLoc, RPLoc)); 6609} 6610 6611Sema::OwningExprResult Sema::BuildBuiltinOffsetOf(SourceLocation BuiltinLoc, 6612 TypeSourceInfo *TInfo, 6613 OffsetOfComponent *CompPtr, 6614 unsigned NumComponents, 6615 SourceLocation RParenLoc) { 6616 QualType ArgTy = TInfo->getType(); 6617 bool Dependent = ArgTy->isDependentType(); 6618 SourceRange TypeRange = TInfo->getTypeLoc().getLocalSourceRange(); 6619 6620 // We must have at least one component that refers to the type, and the first 6621 // one is known to be a field designator. Verify that the ArgTy represents 6622 // a struct/union/class. 6623 if (!Dependent && !ArgTy->isRecordType()) 6624 return ExprError(Diag(BuiltinLoc, diag::err_offsetof_record_type) 6625 << ArgTy << TypeRange); 6626 6627 // Type must be complete per C99 7.17p3 because a declaring a variable 6628 // with an incomplete type would be ill-formed. 6629 if (!Dependent 6630 && RequireCompleteType(BuiltinLoc, ArgTy, 6631 PDiag(diag::err_offsetof_incomplete_type) 6632 << TypeRange)) 6633 return ExprError(); 6634 6635 // offsetof with non-identifier designators (e.g. "offsetof(x, a.b[c])") are a 6636 // GCC extension, diagnose them. 6637 // FIXME: This diagnostic isn't actually visible because the location is in 6638 // a system header! 6639 if (NumComponents != 1) 6640 Diag(BuiltinLoc, diag::ext_offsetof_extended_field_designator) 6641 << SourceRange(CompPtr[1].LocStart, CompPtr[NumComponents-1].LocEnd); 6642 6643 bool DidWarnAboutNonPOD = false; 6644 QualType CurrentType = ArgTy; 6645 typedef OffsetOfExpr::OffsetOfNode OffsetOfNode; 6646 llvm::SmallVector<OffsetOfNode, 4> Comps; 6647 llvm::SmallVector<Expr*, 4> Exprs; 6648 for (unsigned i = 0; i != NumComponents; ++i) { 6649 const OffsetOfComponent &OC = CompPtr[i]; 6650 if (OC.isBrackets) { 6651 // Offset of an array sub-field. TODO: Should we allow vector elements? 6652 if (!CurrentType->isDependentType()) { 6653 const ArrayType *AT = Context.getAsArrayType(CurrentType); 6654 if(!AT) 6655 return ExprError(Diag(OC.LocEnd, diag::err_offsetof_array_type) 6656 << CurrentType); 6657 CurrentType = AT->getElementType(); 6658 } else 6659 CurrentType = Context.DependentTy; 6660 6661 // The expression must be an integral expression. 6662 // FIXME: An integral constant expression? 6663 Expr *Idx = static_cast<Expr*>(OC.U.E); 6664 if (!Idx->isTypeDependent() && !Idx->isValueDependent() && 6665 !Idx->getType()->isIntegerType()) 6666 return ExprError(Diag(Idx->getLocStart(), 6667 diag::err_typecheck_subscript_not_integer) 6668 << Idx->getSourceRange()); 6669 6670 // Record this array index. 6671 Comps.push_back(OffsetOfNode(OC.LocStart, Exprs.size(), OC.LocEnd)); 6672 Exprs.push_back(Idx); 6673 continue; 6674 } 6675 6676 // Offset of a field. 6677 if (CurrentType->isDependentType()) { 6678 // We have the offset of a field, but we can't look into the dependent 6679 // type. Just record the identifier of the field. 6680 Comps.push_back(OffsetOfNode(OC.LocStart, OC.U.IdentInfo, OC.LocEnd)); 6681 CurrentType = Context.DependentTy; 6682 continue; 6683 } 6684 6685 // We need to have a complete type to look into. 6686 if (RequireCompleteType(OC.LocStart, CurrentType, 6687 diag::err_offsetof_incomplete_type)) 6688 return ExprError(); 6689 6690 // Look for the designated field. 6691 const RecordType *RC = CurrentType->getAs<RecordType>(); 6692 if (!RC) 6693 return ExprError(Diag(OC.LocEnd, diag::err_offsetof_record_type) 6694 << CurrentType); 6695 RecordDecl *RD = RC->getDecl(); 6696 6697 // C++ [lib.support.types]p5: 6698 // The macro offsetof accepts a restricted set of type arguments in this 6699 // International Standard. type shall be a POD structure or a POD union 6700 // (clause 9). 6701 if (CXXRecordDecl *CRD = dyn_cast<CXXRecordDecl>(RD)) { 6702 if (!CRD->isPOD() && !DidWarnAboutNonPOD && 6703 DiagRuntimeBehavior(BuiltinLoc, 6704 PDiag(diag::warn_offsetof_non_pod_type) 6705 << SourceRange(CompPtr[0].LocStart, OC.LocEnd) 6706 << CurrentType)) 6707 DidWarnAboutNonPOD = true; 6708 } 6709 6710 // Look for the field. 6711 LookupResult R(*this, OC.U.IdentInfo, OC.LocStart, LookupMemberName); 6712 LookupQualifiedName(R, RD); 6713 FieldDecl *MemberDecl = R.getAsSingle<FieldDecl>(); 6714 if (!MemberDecl) 6715 return ExprError(Diag(BuiltinLoc, diag::err_no_member) 6716 << OC.U.IdentInfo << RD << SourceRange(OC.LocStart, 6717 OC.LocEnd)); 6718 6719 // C99 7.17p3: 6720 // (If the specified member is a bit-field, the behavior is undefined.) 6721 // 6722 // We diagnose this as an error. 6723 if (MemberDecl->getBitWidth()) { 6724 Diag(OC.LocEnd, diag::err_offsetof_bitfield) 6725 << MemberDecl->getDeclName() 6726 << SourceRange(BuiltinLoc, RParenLoc); 6727 Diag(MemberDecl->getLocation(), diag::note_bitfield_decl); 6728 return ExprError(); 6729 } 6730 6731 // If the member was found in a base class, introduce OffsetOfNodes for 6732 // the base class indirections. 6733 CXXBasePaths Paths(/*FindAmbiguities=*/true, /*RecordPaths=*/true, 6734 /*DetectVirtual=*/false); 6735 if (IsDerivedFrom(CurrentType, 6736 Context.getTypeDeclType(MemberDecl->getParent()), 6737 Paths)) { 6738 CXXBasePath &Path = Paths.front(); 6739 for (CXXBasePath::iterator B = Path.begin(), BEnd = Path.end(); 6740 B != BEnd; ++B) 6741 Comps.push_back(OffsetOfNode(B->Base)); 6742 } 6743 6744 if (cast<RecordDecl>(MemberDecl->getDeclContext())-> 6745 isAnonymousStructOrUnion()) { 6746 llvm::SmallVector<FieldDecl*, 4> Path; 6747 BuildAnonymousStructUnionMemberPath(MemberDecl, Path); 6748 unsigned n = Path.size(); 6749 for (int j = n - 1; j > -1; --j) 6750 Comps.push_back(OffsetOfNode(OC.LocStart, Path[j], OC.LocEnd)); 6751 } else { 6752 Comps.push_back(OffsetOfNode(OC.LocStart, MemberDecl, OC.LocEnd)); 6753 } 6754 CurrentType = MemberDecl->getType().getNonReferenceType(); 6755 } 6756 6757 return Owned(OffsetOfExpr::Create(Context, Context.getSizeType(), BuiltinLoc, 6758 TInfo, Comps.data(), Comps.size(), 6759 Exprs.data(), Exprs.size(), RParenLoc)); 6760} 6761 6762Sema::OwningExprResult Sema::ActOnBuiltinOffsetOf(Scope *S, 6763 SourceLocation BuiltinLoc, 6764 SourceLocation TypeLoc, 6765 TypeTy *argty, 6766 OffsetOfComponent *CompPtr, 6767 unsigned NumComponents, 6768 SourceLocation RPLoc) { 6769 6770 TypeSourceInfo *ArgTInfo; 6771 QualType ArgTy = GetTypeFromParser(argty, &ArgTInfo); 6772 if (ArgTy.isNull()) 6773 return ExprError(); 6774 6775 if (getLangOptions().CPlusPlus) { 6776 if (!ArgTInfo) 6777 ArgTInfo = Context.getTrivialTypeSourceInfo(ArgTy, TypeLoc); 6778 6779 return BuildBuiltinOffsetOf(BuiltinLoc, ArgTInfo, CompPtr, NumComponents, 6780 RPLoc); 6781 } 6782 6783 // FIXME: The code below is marked for death, once we have proper CodeGen 6784 // support for non-constant OffsetOf expressions. 6785 6786 bool Dependent = ArgTy->isDependentType(); 6787 6788 // We must have at least one component that refers to the type, and the first 6789 // one is known to be a field designator. Verify that the ArgTy represents 6790 // a struct/union/class. 6791 if (!Dependent && !ArgTy->isRecordType()) 6792 return ExprError(Diag(TypeLoc, diag::err_offsetof_record_type) << ArgTy); 6793 6794 // FIXME: Type must be complete per C99 7.17p3 because a declaring a variable 6795 // with an incomplete type would be illegal. 6796 6797 // Otherwise, create a null pointer as the base, and iteratively process 6798 // the offsetof designators. 6799 QualType ArgTyPtr = Context.getPointerType(ArgTy); 6800 Expr* Res = new (Context) ImplicitValueInitExpr(ArgTyPtr); 6801 Res = new (Context) UnaryOperator(Res, UnaryOperator::Deref, 6802 ArgTy, SourceLocation()); 6803 6804 // offsetof with non-identifier designators (e.g. "offsetof(x, a.b[c])") are a 6805 // GCC extension, diagnose them. 6806 // FIXME: This diagnostic isn't actually visible because the location is in 6807 // a system header! 6808 if (NumComponents != 1) 6809 Diag(BuiltinLoc, diag::ext_offsetof_extended_field_designator) 6810 << SourceRange(CompPtr[1].LocStart, CompPtr[NumComponents-1].LocEnd); 6811 6812 if (!Dependent) { 6813 bool DidWarnAboutNonPOD = false; 6814 6815 if (RequireCompleteType(TypeLoc, Res->getType(), 6816 diag::err_offsetof_incomplete_type)) 6817 return ExprError(); 6818 6819 // FIXME: Dependent case loses a lot of information here. And probably 6820 // leaks like a sieve. 6821 for (unsigned i = 0; i != NumComponents; ++i) { 6822 const OffsetOfComponent &OC = CompPtr[i]; 6823 if (OC.isBrackets) { 6824 // Offset of an array sub-field. TODO: Should we allow vector elements? 6825 const ArrayType *AT = Context.getAsArrayType(Res->getType()); 6826 if (!AT) { 6827 Res->Destroy(Context); 6828 return ExprError(Diag(OC.LocEnd, diag::err_offsetof_array_type) 6829 << Res->getType()); 6830 } 6831 6832 // FIXME: C++: Verify that operator[] isn't overloaded. 6833 6834 // Promote the array so it looks more like a normal array subscript 6835 // expression. 6836 DefaultFunctionArrayLvalueConversion(Res); 6837 6838 // C99 6.5.2.1p1 6839 Expr *Idx = static_cast<Expr*>(OC.U.E); 6840 // FIXME: Leaks Res 6841 if (!Idx->isTypeDependent() && !Idx->getType()->isIntegerType()) 6842 return ExprError(Diag(Idx->getLocStart(), 6843 diag::err_typecheck_subscript_not_integer) 6844 << Idx->getSourceRange()); 6845 6846 Res = new (Context) ArraySubscriptExpr(Res, Idx, AT->getElementType(), 6847 OC.LocEnd); 6848 continue; 6849 } 6850 6851 const RecordType *RC = Res->getType()->getAs<RecordType>(); 6852 if (!RC) { 6853 Res->Destroy(Context); 6854 return ExprError(Diag(OC.LocEnd, diag::err_offsetof_record_type) 6855 << Res->getType()); 6856 } 6857 6858 // Get the decl corresponding to this. 6859 RecordDecl *RD = RC->getDecl(); 6860 if (CXXRecordDecl *CRD = dyn_cast<CXXRecordDecl>(RD)) { 6861 if (!CRD->isPOD() && !DidWarnAboutNonPOD && 6862 DiagRuntimeBehavior(BuiltinLoc, 6863 PDiag(diag::warn_offsetof_non_pod_type) 6864 << SourceRange(CompPtr[0].LocStart, OC.LocEnd) 6865 << Res->getType())) 6866 DidWarnAboutNonPOD = true; 6867 } 6868 6869 LookupResult R(*this, OC.U.IdentInfo, OC.LocStart, LookupMemberName); 6870 LookupQualifiedName(R, RD); 6871 6872 FieldDecl *MemberDecl = R.getAsSingle<FieldDecl>(); 6873 // FIXME: Leaks Res 6874 if (!MemberDecl) 6875 return ExprError(Diag(BuiltinLoc, diag::err_no_member) 6876 << OC.U.IdentInfo << RD << SourceRange(OC.LocStart, OC.LocEnd)); 6877 6878 // C99 7.17p3: 6879 // (If the specified member is a bit-field, the behavior is undefined.) 6880 // 6881 // We diagnose this as an error. 6882 if (MemberDecl->getBitWidth()) { 6883 Diag(OC.LocEnd, diag::err_offsetof_bitfield) 6884 << MemberDecl->getDeclName() 6885 << SourceRange(BuiltinLoc, RPLoc); 6886 Diag(MemberDecl->getLocation(), diag::note_bitfield_decl); 6887 return ExprError(); 6888 } 6889 6890 // FIXME: C++: Verify that MemberDecl isn't a static field. 6891 // FIXME: Verify that MemberDecl isn't a bitfield. 6892 if (cast<RecordDecl>(MemberDecl->getDeclContext())->isAnonymousStructOrUnion()) { 6893 Res = BuildAnonymousStructUnionMemberReference( 6894 OC.LocEnd, MemberDecl, Res, OC.LocEnd).takeAs<Expr>(); 6895 } else { 6896 PerformObjectMemberConversion(Res, /*Qualifier=*/0, 6897 *R.begin(), MemberDecl); 6898 // MemberDecl->getType() doesn't get the right qualifiers, but it 6899 // doesn't matter here. 6900 Res = new (Context) MemberExpr(Res, false, MemberDecl, OC.LocEnd, 6901 MemberDecl->getType().getNonReferenceType()); 6902 } 6903 } 6904 } 6905 6906 return Owned(new (Context) UnaryOperator(Res, UnaryOperator::OffsetOf, 6907 Context.getSizeType(), BuiltinLoc)); 6908} 6909 6910 6911Sema::OwningExprResult Sema::ActOnTypesCompatibleExpr(SourceLocation BuiltinLoc, 6912 TypeTy *arg1,TypeTy *arg2, 6913 SourceLocation RPLoc) { 6914 // FIXME: Preserve type source info. 6915 QualType argT1 = GetTypeFromParser(arg1); 6916 QualType argT2 = GetTypeFromParser(arg2); 6917 6918 assert((!argT1.isNull() && !argT2.isNull()) && "Missing type argument(s)"); 6919 6920 if (getLangOptions().CPlusPlus) { 6921 Diag(BuiltinLoc, diag::err_types_compatible_p_in_cplusplus) 6922 << SourceRange(BuiltinLoc, RPLoc); 6923 return ExprError(); 6924 } 6925 6926 return Owned(new (Context) TypesCompatibleExpr(Context.IntTy, BuiltinLoc, 6927 argT1, argT2, RPLoc)); 6928} 6929 6930Sema::OwningExprResult Sema::ActOnChooseExpr(SourceLocation BuiltinLoc, 6931 ExprArg cond, 6932 ExprArg expr1, ExprArg expr2, 6933 SourceLocation RPLoc) { 6934 Expr *CondExpr = static_cast<Expr*>(cond.get()); 6935 Expr *LHSExpr = static_cast<Expr*>(expr1.get()); 6936 Expr *RHSExpr = static_cast<Expr*>(expr2.get()); 6937 6938 assert((CondExpr && LHSExpr && RHSExpr) && "Missing type argument(s)"); 6939 6940 QualType resType; 6941 bool ValueDependent = false; 6942 if (CondExpr->isTypeDependent() || CondExpr->isValueDependent()) { 6943 resType = Context.DependentTy; 6944 ValueDependent = true; 6945 } else { 6946 // The conditional expression is required to be a constant expression. 6947 llvm::APSInt condEval(32); 6948 SourceLocation ExpLoc; 6949 if (!CondExpr->isIntegerConstantExpr(condEval, Context, &ExpLoc)) 6950 return ExprError(Diag(ExpLoc, 6951 diag::err_typecheck_choose_expr_requires_constant) 6952 << CondExpr->getSourceRange()); 6953 6954 // If the condition is > zero, then the AST type is the same as the LSHExpr. 6955 resType = condEval.getZExtValue() ? LHSExpr->getType() : RHSExpr->getType(); 6956 ValueDependent = condEval.getZExtValue() ? LHSExpr->isValueDependent() 6957 : RHSExpr->isValueDependent(); 6958 } 6959 6960 cond.release(); expr1.release(); expr2.release(); 6961 return Owned(new (Context) ChooseExpr(BuiltinLoc, CondExpr, LHSExpr, RHSExpr, 6962 resType, RPLoc, 6963 resType->isDependentType(), 6964 ValueDependent)); 6965} 6966 6967//===----------------------------------------------------------------------===// 6968// Clang Extensions. 6969//===----------------------------------------------------------------------===// 6970 6971/// ActOnBlockStart - This callback is invoked when a block literal is started. 6972void Sema::ActOnBlockStart(SourceLocation CaretLoc, Scope *BlockScope) { 6973 BlockDecl *Block = BlockDecl::Create(Context, CurContext, CaretLoc); 6974 PushBlockScope(BlockScope, Block); 6975 CurContext->addDecl(Block); 6976 PushDeclContext(BlockScope, Block); 6977} 6978 6979void Sema::ActOnBlockArguments(Declarator &ParamInfo, Scope *CurScope) { 6980 assert(ParamInfo.getIdentifier()==0 && "block-id should have no identifier!"); 6981 BlockScopeInfo *CurBlock = getCurBlock(); 6982 6983 if (ParamInfo.getNumTypeObjects() == 0 6984 || ParamInfo.getTypeObject(0).Kind != DeclaratorChunk::Function) { 6985 ProcessDeclAttributes(CurScope, CurBlock->TheDecl, ParamInfo); 6986 QualType T = GetTypeForDeclarator(ParamInfo, CurScope); 6987 6988 if (T->isArrayType()) { 6989 Diag(ParamInfo.getSourceRange().getBegin(), 6990 diag::err_block_returns_array); 6991 return; 6992 } 6993 6994 // The parameter list is optional, if there was none, assume (). 6995 if (!T->isFunctionType()) 6996 T = Context.getFunctionType(T, 0, 0, false, 0, false, false, 0, 0, 6997 FunctionType::ExtInfo()); 6998 6999 CurBlock->hasPrototype = true; 7000 CurBlock->isVariadic = false; 7001 // Check for a valid sentinel attribute on this block. 7002 if (CurBlock->TheDecl->getAttr<SentinelAttr>()) { 7003 Diag(ParamInfo.getAttributes()->getLoc(), 7004 diag::warn_attribute_sentinel_not_variadic) << 1; 7005 // FIXME: remove the attribute. 7006 } 7007 QualType RetTy = T.getTypePtr()->getAs<FunctionType>()->getResultType(); 7008 7009 // Do not allow returning a objc interface by-value. 7010 if (RetTy->isObjCObjectType()) { 7011 Diag(ParamInfo.getSourceRange().getBegin(), 7012 diag::err_object_cannot_be_passed_returned_by_value) << 0 << RetTy; 7013 return; 7014 } 7015 7016 CurBlock->ReturnType = RetTy; 7017 return; 7018 } 7019 7020 // Analyze arguments to block. 7021 assert(ParamInfo.getTypeObject(0).Kind == DeclaratorChunk::Function && 7022 "Not a function declarator!"); 7023 DeclaratorChunk::FunctionTypeInfo &FTI = ParamInfo.getTypeObject(0).Fun; 7024 7025 CurBlock->hasPrototype = FTI.hasPrototype; 7026 CurBlock->isVariadic = true; 7027 7028 // Check for C99 6.7.5.3p10 - foo(void) is a non-varargs function that takes 7029 // no arguments, not a function that takes a single void argument. 7030 if (FTI.hasPrototype && 7031 FTI.NumArgs == 1 && !FTI.isVariadic && FTI.ArgInfo[0].Ident == 0 && 7032 (!FTI.ArgInfo[0].Param.getAs<ParmVarDecl>()->getType().getCVRQualifiers()&& 7033 FTI.ArgInfo[0].Param.getAs<ParmVarDecl>()->getType()->isVoidType())) { 7034 // empty arg list, don't push any params. 7035 CurBlock->isVariadic = false; 7036 } else if (FTI.hasPrototype) { 7037 for (unsigned i = 0, e = FTI.NumArgs; i != e; ++i) { 7038 ParmVarDecl *Param = FTI.ArgInfo[i].Param.getAs<ParmVarDecl>(); 7039 if (Param->getIdentifier() == 0 && 7040 !Param->isImplicit() && 7041 !Param->isInvalidDecl() && 7042 !getLangOptions().CPlusPlus) 7043 Diag(Param->getLocation(), diag::err_parameter_name_omitted); 7044 CurBlock->Params.push_back(Param); 7045 } 7046 CurBlock->isVariadic = FTI.isVariadic; 7047 } 7048 CurBlock->TheDecl->setParams(CurBlock->Params.data(), 7049 CurBlock->Params.size()); 7050 CurBlock->TheDecl->setIsVariadic(CurBlock->isVariadic); 7051 ProcessDeclAttributes(CurScope, CurBlock->TheDecl, ParamInfo); 7052 7053 bool ShouldCheckShadow = 7054 Diags.getDiagnosticLevel(diag::warn_decl_shadow) != Diagnostic::Ignored; 7055 7056 for (BlockDecl::param_iterator AI = CurBlock->TheDecl->param_begin(), 7057 E = CurBlock->TheDecl->param_end(); AI != E; ++AI) { 7058 (*AI)->setOwningFunction(CurBlock->TheDecl); 7059 7060 // If this has an identifier, add it to the scope stack. 7061 if ((*AI)->getIdentifier()) { 7062 if (ShouldCheckShadow) 7063 CheckShadow(CurBlock->TheScope, *AI); 7064 7065 PushOnScopeChains(*AI, CurBlock->TheScope); 7066 } 7067 } 7068 7069 // Check for a valid sentinel attribute on this block. 7070 if (!CurBlock->isVariadic && 7071 CurBlock->TheDecl->getAttr<SentinelAttr>()) { 7072 Diag(ParamInfo.getAttributes()->getLoc(), 7073 diag::warn_attribute_sentinel_not_variadic) << 1; 7074 // FIXME: remove the attribute. 7075 } 7076 7077 // Analyze the return type. 7078 QualType T = GetTypeForDeclarator(ParamInfo, CurScope); 7079 QualType RetTy = T->getAs<FunctionType>()->getResultType(); 7080 7081 // Do not allow returning a objc interface by-value. 7082 if (RetTy->isObjCObjectType()) { 7083 Diag(ParamInfo.getSourceRange().getBegin(), 7084 diag::err_object_cannot_be_passed_returned_by_value) << 0 << RetTy; 7085 } else if (!RetTy->isDependentType()) 7086 CurBlock->ReturnType = RetTy; 7087} 7088 7089/// ActOnBlockError - If there is an error parsing a block, this callback 7090/// is invoked to pop the information about the block from the action impl. 7091void Sema::ActOnBlockError(SourceLocation CaretLoc, Scope *CurScope) { 7092 // Pop off CurBlock, handle nested blocks. 7093 PopDeclContext(); 7094 PopFunctionOrBlockScope(); 7095 // FIXME: Delete the ParmVarDecl objects as well??? 7096} 7097 7098/// ActOnBlockStmtExpr - This is called when the body of a block statement 7099/// literal was successfully completed. ^(int x){...} 7100Sema::OwningExprResult Sema::ActOnBlockStmtExpr(SourceLocation CaretLoc, 7101 StmtArg body, Scope *CurScope) { 7102 // If blocks are disabled, emit an error. 7103 if (!LangOpts.Blocks) 7104 Diag(CaretLoc, diag::err_blocks_disable); 7105 7106 BlockScopeInfo *BSI = cast<BlockScopeInfo>(FunctionScopes.back()); 7107 7108 PopDeclContext(); 7109 7110 QualType RetTy = Context.VoidTy; 7111 if (!BSI->ReturnType.isNull()) 7112 RetTy = BSI->ReturnType; 7113 7114 llvm::SmallVector<QualType, 8> ArgTypes; 7115 for (unsigned i = 0, e = BSI->Params.size(); i != e; ++i) 7116 ArgTypes.push_back(BSI->Params[i]->getType()); 7117 7118 bool NoReturn = BSI->TheDecl->getAttr<NoReturnAttr>(); 7119 QualType BlockTy; 7120 if (!BSI->hasPrototype) 7121 BlockTy = Context.getFunctionType(RetTy, 0, 0, false, 0, false, false, 0, 0, 7122 FunctionType::ExtInfo(NoReturn, 0, CC_Default)); 7123 else 7124 BlockTy = Context.getFunctionType(RetTy, ArgTypes.data(), ArgTypes.size(), 7125 BSI->isVariadic, 0, false, false, 0, 0, 7126 FunctionType::ExtInfo(NoReturn, 0, CC_Default)); 7127 7128 // FIXME: Check that return/parameter types are complete/non-abstract 7129 DiagnoseUnusedParameters(BSI->Params.begin(), BSI->Params.end()); 7130 BlockTy = Context.getBlockPointerType(BlockTy); 7131 7132 // If needed, diagnose invalid gotos and switches in the block. 7133 if (FunctionNeedsScopeChecking() && !hasAnyErrorsInThisFunction()) 7134 DiagnoseInvalidJumps(static_cast<CompoundStmt*>(body.get())); 7135 7136 BSI->TheDecl->setBody(body.takeAs<CompoundStmt>()); 7137 7138 bool Good = true; 7139 // Check goto/label use. 7140 for (llvm::DenseMap<IdentifierInfo*, LabelStmt*>::iterator 7141 I = BSI->LabelMap.begin(), E = BSI->LabelMap.end(); I != E; ++I) { 7142 LabelStmt *L = I->second; 7143 7144 // Verify that we have no forward references left. If so, there was a goto 7145 // or address of a label taken, but no definition of it. 7146 if (L->getSubStmt() != 0) 7147 continue; 7148 7149 // Emit error. 7150 Diag(L->getIdentLoc(), diag::err_undeclared_label_use) << L->getName(); 7151 Good = false; 7152 } 7153 if (!Good) { 7154 PopFunctionOrBlockScope(); 7155 return ExprError(); 7156 } 7157 7158 // Issue any analysis-based warnings. 7159 const sema::AnalysisBasedWarnings::Policy &WP = 7160 AnalysisWarnings.getDefaultPolicy(); 7161 AnalysisWarnings.IssueWarnings(WP, BSI->TheDecl, BlockTy); 7162 7163 Expr *Result = new (Context) BlockExpr(BSI->TheDecl, BlockTy, 7164 BSI->hasBlockDeclRefExprs); 7165 PopFunctionOrBlockScope(); 7166 return Owned(Result); 7167} 7168 7169Sema::OwningExprResult Sema::ActOnVAArg(SourceLocation BuiltinLoc, 7170 ExprArg expr, TypeTy *type, 7171 SourceLocation RPLoc) { 7172 QualType T = GetTypeFromParser(type); 7173 Expr *E = static_cast<Expr*>(expr.get()); 7174 Expr *OrigExpr = E; 7175 7176 InitBuiltinVaListType(); 7177 7178 // Get the va_list type 7179 QualType VaListType = Context.getBuiltinVaListType(); 7180 if (VaListType->isArrayType()) { 7181 // Deal with implicit array decay; for example, on x86-64, 7182 // va_list is an array, but it's supposed to decay to 7183 // a pointer for va_arg. 7184 VaListType = Context.getArrayDecayedType(VaListType); 7185 // Make sure the input expression also decays appropriately. 7186 UsualUnaryConversions(E); 7187 } else { 7188 // Otherwise, the va_list argument must be an l-value because 7189 // it is modified by va_arg. 7190 if (!E->isTypeDependent() && 7191 CheckForModifiableLvalue(E, BuiltinLoc, *this)) 7192 return ExprError(); 7193 } 7194 7195 if (!E->isTypeDependent() && 7196 !Context.hasSameType(VaListType, E->getType())) { 7197 return ExprError(Diag(E->getLocStart(), 7198 diag::err_first_argument_to_va_arg_not_of_type_va_list) 7199 << OrigExpr->getType() << E->getSourceRange()); 7200 } 7201 7202 // FIXME: Check that type is complete/non-abstract 7203 // FIXME: Warn if a non-POD type is passed in. 7204 7205 expr.release(); 7206 return Owned(new (Context) VAArgExpr(BuiltinLoc, E, T.getNonReferenceType(), 7207 RPLoc)); 7208} 7209 7210Sema::OwningExprResult Sema::ActOnGNUNullExpr(SourceLocation TokenLoc) { 7211 // The type of __null will be int or long, depending on the size of 7212 // pointers on the target. 7213 QualType Ty; 7214 if (Context.Target.getPointerWidth(0) == Context.Target.getIntWidth()) 7215 Ty = Context.IntTy; 7216 else 7217 Ty = Context.LongTy; 7218 7219 return Owned(new (Context) GNUNullExpr(Ty, TokenLoc)); 7220} 7221 7222static void MakeObjCStringLiteralFixItHint(Sema& SemaRef, QualType DstType, 7223 Expr *SrcExpr, FixItHint &Hint) { 7224 if (!SemaRef.getLangOptions().ObjC1) 7225 return; 7226 7227 const ObjCObjectPointerType *PT = DstType->getAs<ObjCObjectPointerType>(); 7228 if (!PT) 7229 return; 7230 7231 // Check if the destination is of type 'id'. 7232 if (!PT->isObjCIdType()) { 7233 // Check if the destination is the 'NSString' interface. 7234 const ObjCInterfaceDecl *ID = PT->getInterfaceDecl(); 7235 if (!ID || !ID->getIdentifier()->isStr("NSString")) 7236 return; 7237 } 7238 7239 // Strip off any parens and casts. 7240 StringLiteral *SL = dyn_cast<StringLiteral>(SrcExpr->IgnoreParenCasts()); 7241 if (!SL || SL->isWide()) 7242 return; 7243 7244 Hint = FixItHint::CreateInsertion(SL->getLocStart(), "@"); 7245} 7246 7247bool Sema::DiagnoseAssignmentResult(AssignConvertType ConvTy, 7248 SourceLocation Loc, 7249 QualType DstType, QualType SrcType, 7250 Expr *SrcExpr, AssignmentAction Action, 7251 bool *Complained) { 7252 if (Complained) 7253 *Complained = false; 7254 7255 // Decode the result (notice that AST's are still created for extensions). 7256 bool isInvalid = false; 7257 unsigned DiagKind; 7258 FixItHint Hint; 7259 7260 switch (ConvTy) { 7261 default: assert(0 && "Unknown conversion type"); 7262 case Compatible: return false; 7263 case PointerToInt: 7264 DiagKind = diag::ext_typecheck_convert_pointer_int; 7265 break; 7266 case IntToPointer: 7267 DiagKind = diag::ext_typecheck_convert_int_pointer; 7268 break; 7269 case IncompatiblePointer: 7270 MakeObjCStringLiteralFixItHint(*this, DstType, SrcExpr, Hint); 7271 DiagKind = diag::ext_typecheck_convert_incompatible_pointer; 7272 break; 7273 case IncompatiblePointerSign: 7274 DiagKind = diag::ext_typecheck_convert_incompatible_pointer_sign; 7275 break; 7276 case FunctionVoidPointer: 7277 DiagKind = diag::ext_typecheck_convert_pointer_void_func; 7278 break; 7279 case CompatiblePointerDiscardsQualifiers: 7280 // If the qualifiers lost were because we were applying the 7281 // (deprecated) C++ conversion from a string literal to a char* 7282 // (or wchar_t*), then there was no error (C++ 4.2p2). FIXME: 7283 // Ideally, this check would be performed in 7284 // CheckPointerTypesForAssignment. However, that would require a 7285 // bit of refactoring (so that the second argument is an 7286 // expression, rather than a type), which should be done as part 7287 // of a larger effort to fix CheckPointerTypesForAssignment for 7288 // C++ semantics. 7289 if (getLangOptions().CPlusPlus && 7290 IsStringLiteralToNonConstPointerConversion(SrcExpr, DstType)) 7291 return false; 7292 DiagKind = diag::ext_typecheck_convert_discards_qualifiers; 7293 break; 7294 case IncompatibleNestedPointerQualifiers: 7295 DiagKind = diag::ext_nested_pointer_qualifier_mismatch; 7296 break; 7297 case IntToBlockPointer: 7298 DiagKind = diag::err_int_to_block_pointer; 7299 break; 7300 case IncompatibleBlockPointer: 7301 DiagKind = diag::err_typecheck_convert_incompatible_block_pointer; 7302 break; 7303 case IncompatibleObjCQualifiedId: 7304 // FIXME: Diagnose the problem in ObjCQualifiedIdTypesAreCompatible, since 7305 // it can give a more specific diagnostic. 7306 DiagKind = diag::warn_incompatible_qualified_id; 7307 break; 7308 case IncompatibleVectors: 7309 DiagKind = diag::warn_incompatible_vectors; 7310 break; 7311 case Incompatible: 7312 DiagKind = diag::err_typecheck_convert_incompatible; 7313 isInvalid = true; 7314 break; 7315 } 7316 7317 QualType FirstType, SecondType; 7318 switch (Action) { 7319 case AA_Assigning: 7320 case AA_Initializing: 7321 // The destination type comes first. 7322 FirstType = DstType; 7323 SecondType = SrcType; 7324 break; 7325 7326 case AA_Returning: 7327 case AA_Passing: 7328 case AA_Converting: 7329 case AA_Sending: 7330 case AA_Casting: 7331 // The source type comes first. 7332 FirstType = SrcType; 7333 SecondType = DstType; 7334 break; 7335 } 7336 7337 Diag(Loc, DiagKind) << FirstType << SecondType << Action 7338 << SrcExpr->getSourceRange() << Hint; 7339 if (Complained) 7340 *Complained = true; 7341 return isInvalid; 7342} 7343 7344bool Sema::VerifyIntegerConstantExpression(const Expr *E, llvm::APSInt *Result){ 7345 llvm::APSInt ICEResult; 7346 if (E->isIntegerConstantExpr(ICEResult, Context)) { 7347 if (Result) 7348 *Result = ICEResult; 7349 return false; 7350 } 7351 7352 Expr::EvalResult EvalResult; 7353 7354 if (!E->Evaluate(EvalResult, Context) || !EvalResult.Val.isInt() || 7355 EvalResult.HasSideEffects) { 7356 Diag(E->getExprLoc(), diag::err_expr_not_ice) << E->getSourceRange(); 7357 7358 if (EvalResult.Diag) { 7359 // We only show the note if it's not the usual "invalid subexpression" 7360 // or if it's actually in a subexpression. 7361 if (EvalResult.Diag != diag::note_invalid_subexpr_in_ice || 7362 E->IgnoreParens() != EvalResult.DiagExpr->IgnoreParens()) 7363 Diag(EvalResult.DiagLoc, EvalResult.Diag); 7364 } 7365 7366 return true; 7367 } 7368 7369 Diag(E->getExprLoc(), diag::ext_expr_not_ice) << 7370 E->getSourceRange(); 7371 7372 if (EvalResult.Diag && 7373 Diags.getDiagnosticLevel(diag::ext_expr_not_ice) != Diagnostic::Ignored) 7374 Diag(EvalResult.DiagLoc, EvalResult.Diag); 7375 7376 if (Result) 7377 *Result = EvalResult.Val.getInt(); 7378 return false; 7379} 7380 7381void 7382Sema::PushExpressionEvaluationContext(ExpressionEvaluationContext NewContext) { 7383 ExprEvalContexts.push_back( 7384 ExpressionEvaluationContextRecord(NewContext, ExprTemporaries.size())); 7385} 7386 7387void 7388Sema::PopExpressionEvaluationContext() { 7389 // Pop the current expression evaluation context off the stack. 7390 ExpressionEvaluationContextRecord Rec = ExprEvalContexts.back(); 7391 ExprEvalContexts.pop_back(); 7392 7393 if (Rec.Context == PotentiallyPotentiallyEvaluated) { 7394 if (Rec.PotentiallyReferenced) { 7395 // Mark any remaining declarations in the current position of the stack 7396 // as "referenced". If they were not meant to be referenced, semantic 7397 // analysis would have eliminated them (e.g., in ActOnCXXTypeId). 7398 for (PotentiallyReferencedDecls::iterator 7399 I = Rec.PotentiallyReferenced->begin(), 7400 IEnd = Rec.PotentiallyReferenced->end(); 7401 I != IEnd; ++I) 7402 MarkDeclarationReferenced(I->first, I->second); 7403 } 7404 7405 if (Rec.PotentiallyDiagnosed) { 7406 // Emit any pending diagnostics. 7407 for (PotentiallyEmittedDiagnostics::iterator 7408 I = Rec.PotentiallyDiagnosed->begin(), 7409 IEnd = Rec.PotentiallyDiagnosed->end(); 7410 I != IEnd; ++I) 7411 Diag(I->first, I->second); 7412 } 7413 } 7414 7415 // When are coming out of an unevaluated context, clear out any 7416 // temporaries that we may have created as part of the evaluation of 7417 // the expression in that context: they aren't relevant because they 7418 // will never be constructed. 7419 if (Rec.Context == Unevaluated && 7420 ExprTemporaries.size() > Rec.NumTemporaries) 7421 ExprTemporaries.erase(ExprTemporaries.begin() + Rec.NumTemporaries, 7422 ExprTemporaries.end()); 7423 7424 // Destroy the popped expression evaluation record. 7425 Rec.Destroy(); 7426} 7427 7428/// \brief Note that the given declaration was referenced in the source code. 7429/// 7430/// This routine should be invoke whenever a given declaration is referenced 7431/// in the source code, and where that reference occurred. If this declaration 7432/// reference means that the the declaration is used (C++ [basic.def.odr]p2, 7433/// C99 6.9p3), then the declaration will be marked as used. 7434/// 7435/// \param Loc the location where the declaration was referenced. 7436/// 7437/// \param D the declaration that has been referenced by the source code. 7438void Sema::MarkDeclarationReferenced(SourceLocation Loc, Decl *D) { 7439 assert(D && "No declaration?"); 7440 7441 if (D->isUsed()) 7442 return; 7443 7444 // Mark a parameter or variable declaration "used", regardless of whether we're in a 7445 // template or not. The reason for this is that unevaluated expressions 7446 // (e.g. (void)sizeof()) constitute a use for warning purposes (-Wunused-variables and 7447 // -Wunused-parameters) 7448 if (isa<ParmVarDecl>(D) || 7449 (isa<VarDecl>(D) && D->getDeclContext()->isFunctionOrMethod())) { 7450 D->setUsed(true); 7451 return; 7452 } 7453 7454 if (!isa<VarDecl>(D) && !isa<FunctionDecl>(D)) 7455 return; 7456 7457 // Do not mark anything as "used" within a dependent context; wait for 7458 // an instantiation. 7459 if (CurContext->isDependentContext()) 7460 return; 7461 7462 switch (ExprEvalContexts.back().Context) { 7463 case Unevaluated: 7464 // We are in an expression that is not potentially evaluated; do nothing. 7465 return; 7466 7467 case PotentiallyEvaluated: 7468 // We are in a potentially-evaluated expression, so this declaration is 7469 // "used"; handle this below. 7470 break; 7471 7472 case PotentiallyPotentiallyEvaluated: 7473 // We are in an expression that may be potentially evaluated; queue this 7474 // declaration reference until we know whether the expression is 7475 // potentially evaluated. 7476 ExprEvalContexts.back().addReferencedDecl(Loc, D); 7477 return; 7478 } 7479 7480 // Note that this declaration has been used. 7481 if (CXXConstructorDecl *Constructor = dyn_cast<CXXConstructorDecl>(D)) { 7482 unsigned TypeQuals; 7483 if (Constructor->isImplicit() && Constructor->isDefaultConstructor()) { 7484 if (!Constructor->isUsed()) 7485 DefineImplicitDefaultConstructor(Loc, Constructor); 7486 } else if (Constructor->isImplicit() && 7487 Constructor->isCopyConstructor(TypeQuals)) { 7488 if (!Constructor->isUsed()) 7489 DefineImplicitCopyConstructor(Loc, Constructor, TypeQuals); 7490 } 7491 7492 MarkVTableUsed(Loc, Constructor->getParent()); 7493 } else if (CXXDestructorDecl *Destructor = dyn_cast<CXXDestructorDecl>(D)) { 7494 if (Destructor->isImplicit() && !Destructor->isUsed()) 7495 DefineImplicitDestructor(Loc, Destructor); 7496 if (Destructor->isVirtual()) 7497 MarkVTableUsed(Loc, Destructor->getParent()); 7498 } else if (CXXMethodDecl *MethodDecl = dyn_cast<CXXMethodDecl>(D)) { 7499 if (MethodDecl->isImplicit() && MethodDecl->isOverloadedOperator() && 7500 MethodDecl->getOverloadedOperator() == OO_Equal) { 7501 if (!MethodDecl->isUsed()) 7502 DefineImplicitCopyAssignment(Loc, MethodDecl); 7503 } else if (MethodDecl->isVirtual()) 7504 MarkVTableUsed(Loc, MethodDecl->getParent()); 7505 } 7506 if (FunctionDecl *Function = dyn_cast<FunctionDecl>(D)) { 7507 // Implicit instantiation of function templates and member functions of 7508 // class templates. 7509 if (Function->isImplicitlyInstantiable()) { 7510 bool AlreadyInstantiated = false; 7511 if (FunctionTemplateSpecializationInfo *SpecInfo 7512 = Function->getTemplateSpecializationInfo()) { 7513 if (SpecInfo->getPointOfInstantiation().isInvalid()) 7514 SpecInfo->setPointOfInstantiation(Loc); 7515 else if (SpecInfo->getTemplateSpecializationKind() 7516 == TSK_ImplicitInstantiation) 7517 AlreadyInstantiated = true; 7518 } else if (MemberSpecializationInfo *MSInfo 7519 = Function->getMemberSpecializationInfo()) { 7520 if (MSInfo->getPointOfInstantiation().isInvalid()) 7521 MSInfo->setPointOfInstantiation(Loc); 7522 else if (MSInfo->getTemplateSpecializationKind() 7523 == TSK_ImplicitInstantiation) 7524 AlreadyInstantiated = true; 7525 } 7526 7527 if (!AlreadyInstantiated) { 7528 if (isa<CXXRecordDecl>(Function->getDeclContext()) && 7529 cast<CXXRecordDecl>(Function->getDeclContext())->isLocalClass()) 7530 PendingLocalImplicitInstantiations.push_back(std::make_pair(Function, 7531 Loc)); 7532 else 7533 PendingImplicitInstantiations.push_back(std::make_pair(Function, 7534 Loc)); 7535 } 7536 } 7537 7538 // FIXME: keep track of references to static functions 7539 Function->setUsed(true); 7540 7541 return; 7542 } 7543 7544 if (VarDecl *Var = dyn_cast<VarDecl>(D)) { 7545 // Implicit instantiation of static data members of class templates. 7546 if (Var->isStaticDataMember() && 7547 Var->getInstantiatedFromStaticDataMember()) { 7548 MemberSpecializationInfo *MSInfo = Var->getMemberSpecializationInfo(); 7549 assert(MSInfo && "Missing member specialization information?"); 7550 if (MSInfo->getPointOfInstantiation().isInvalid() && 7551 MSInfo->getTemplateSpecializationKind()== TSK_ImplicitInstantiation) { 7552 MSInfo->setPointOfInstantiation(Loc); 7553 PendingImplicitInstantiations.push_back(std::make_pair(Var, Loc)); 7554 } 7555 } 7556 7557 // FIXME: keep track of references to static data? 7558 7559 D->setUsed(true); 7560 return; 7561 } 7562} 7563 7564namespace { 7565 // Mark all of the declarations referenced 7566 // FIXME: Not fully implemented yet! We need to have a better understanding 7567 // of when we're entering 7568 class MarkReferencedDecls : public RecursiveASTVisitor<MarkReferencedDecls> { 7569 Sema &S; 7570 SourceLocation Loc; 7571 7572 public: 7573 typedef RecursiveASTVisitor<MarkReferencedDecls> Inherited; 7574 7575 MarkReferencedDecls(Sema &S, SourceLocation Loc) : S(S), Loc(Loc) { } 7576 7577 bool VisitTemplateArgument(const TemplateArgument &Arg); 7578 bool VisitRecordType(RecordType *T); 7579 }; 7580} 7581 7582bool MarkReferencedDecls::VisitTemplateArgument(const TemplateArgument &Arg) { 7583 if (Arg.getKind() == TemplateArgument::Declaration) { 7584 S.MarkDeclarationReferenced(Loc, Arg.getAsDecl()); 7585 } 7586 7587 return Inherited::VisitTemplateArgument(Arg); 7588} 7589 7590bool MarkReferencedDecls::VisitRecordType(RecordType *T) { 7591 if (ClassTemplateSpecializationDecl *Spec 7592 = dyn_cast<ClassTemplateSpecializationDecl>(T->getDecl())) { 7593 const TemplateArgumentList &Args = Spec->getTemplateArgs(); 7594 return VisitTemplateArguments(Args.getFlatArgumentList(), 7595 Args.flat_size()); 7596 } 7597 7598 return false; 7599} 7600 7601void Sema::MarkDeclarationsReferencedInType(SourceLocation Loc, QualType T) { 7602 MarkReferencedDecls Marker(*this, Loc); 7603 Marker.Visit(Context.getCanonicalType(T)); 7604} 7605 7606/// \brief Emit a diagnostic that describes an effect on the run-time behavior 7607/// of the program being compiled. 7608/// 7609/// This routine emits the given diagnostic when the code currently being 7610/// type-checked is "potentially evaluated", meaning that there is a 7611/// possibility that the code will actually be executable. Code in sizeof() 7612/// expressions, code used only during overload resolution, etc., are not 7613/// potentially evaluated. This routine will suppress such diagnostics or, 7614/// in the absolutely nutty case of potentially potentially evaluated 7615/// expressions (C++ typeid), queue the diagnostic to potentially emit it 7616/// later. 7617/// 7618/// This routine should be used for all diagnostics that describe the run-time 7619/// behavior of a program, such as passing a non-POD value through an ellipsis. 7620/// Failure to do so will likely result in spurious diagnostics or failures 7621/// during overload resolution or within sizeof/alignof/typeof/typeid. 7622bool Sema::DiagRuntimeBehavior(SourceLocation Loc, 7623 const PartialDiagnostic &PD) { 7624 switch (ExprEvalContexts.back().Context ) { 7625 case Unevaluated: 7626 // The argument will never be evaluated, so don't complain. 7627 break; 7628 7629 case PotentiallyEvaluated: 7630 Diag(Loc, PD); 7631 return true; 7632 7633 case PotentiallyPotentiallyEvaluated: 7634 ExprEvalContexts.back().addDiagnostic(Loc, PD); 7635 break; 7636 } 7637 7638 return false; 7639} 7640 7641bool Sema::CheckCallReturnType(QualType ReturnType, SourceLocation Loc, 7642 CallExpr *CE, FunctionDecl *FD) { 7643 if (ReturnType->isVoidType() || !ReturnType->isIncompleteType()) 7644 return false; 7645 7646 PartialDiagnostic Note = 7647 FD ? PDiag(diag::note_function_with_incomplete_return_type_declared_here) 7648 << FD->getDeclName() : PDiag(); 7649 SourceLocation NoteLoc = FD ? FD->getLocation() : SourceLocation(); 7650 7651 if (RequireCompleteType(Loc, ReturnType, 7652 FD ? 7653 PDiag(diag::err_call_function_incomplete_return) 7654 << CE->getSourceRange() << FD->getDeclName() : 7655 PDiag(diag::err_call_incomplete_return) 7656 << CE->getSourceRange(), 7657 std::make_pair(NoteLoc, Note))) 7658 return true; 7659 7660 return false; 7661} 7662 7663// Diagnose the common s/=/==/ typo. Note that adding parentheses 7664// will prevent this condition from triggering, which is what we want. 7665void Sema::DiagnoseAssignmentAsCondition(Expr *E) { 7666 SourceLocation Loc; 7667 7668 unsigned diagnostic = diag::warn_condition_is_assignment; 7669 7670 if (isa<BinaryOperator>(E)) { 7671 BinaryOperator *Op = cast<BinaryOperator>(E); 7672 if (Op->getOpcode() != BinaryOperator::Assign) 7673 return; 7674 7675 // Greylist some idioms by putting them into a warning subcategory. 7676 if (ObjCMessageExpr *ME 7677 = dyn_cast<ObjCMessageExpr>(Op->getRHS()->IgnoreParenCasts())) { 7678 Selector Sel = ME->getSelector(); 7679 7680 // self = [<foo> init...] 7681 if (isSelfExpr(Op->getLHS()) 7682 && Sel.getIdentifierInfoForSlot(0)->getName().startswith("init")) 7683 diagnostic = diag::warn_condition_is_idiomatic_assignment; 7684 7685 // <foo> = [<bar> nextObject] 7686 else if (Sel.isUnarySelector() && 7687 Sel.getIdentifierInfoForSlot(0)->getName() == "nextObject") 7688 diagnostic = diag::warn_condition_is_idiomatic_assignment; 7689 } 7690 7691 Loc = Op->getOperatorLoc(); 7692 } else if (isa<CXXOperatorCallExpr>(E)) { 7693 CXXOperatorCallExpr *Op = cast<CXXOperatorCallExpr>(E); 7694 if (Op->getOperator() != OO_Equal) 7695 return; 7696 7697 Loc = Op->getOperatorLoc(); 7698 } else { 7699 // Not an assignment. 7700 return; 7701 } 7702 7703 SourceLocation Open = E->getSourceRange().getBegin(); 7704 SourceLocation Close = PP.getLocForEndOfToken(E->getSourceRange().getEnd()); 7705 7706 Diag(Loc, diagnostic) << E->getSourceRange(); 7707 Diag(Loc, diag::note_condition_assign_to_comparison) 7708 << FixItHint::CreateReplacement(Loc, "=="); 7709 Diag(Loc, diag::note_condition_assign_silence) 7710 << FixItHint::CreateInsertion(Open, "(") 7711 << FixItHint::CreateInsertion(Close, ")"); 7712} 7713 7714bool Sema::CheckBooleanCondition(Expr *&E, SourceLocation Loc) { 7715 DiagnoseAssignmentAsCondition(E); 7716 7717 if (!E->isTypeDependent()) { 7718 DefaultFunctionArrayLvalueConversion(E); 7719 7720 QualType T = E->getType(); 7721 7722 if (getLangOptions().CPlusPlus) { 7723 if (CheckCXXBooleanCondition(E)) // C++ 6.4p4 7724 return true; 7725 } else if (!T->isScalarType()) { // C99 6.8.4.1p1 7726 Diag(Loc, diag::err_typecheck_statement_requires_scalar) 7727 << T << E->getSourceRange(); 7728 return true; 7729 } 7730 } 7731 7732 return false; 7733} 7734 7735Sema::OwningExprResult Sema::ActOnBooleanCondition(Scope *S, SourceLocation Loc, 7736 ExprArg SubExpr) { 7737 Expr *Sub = SubExpr.takeAs<Expr>(); 7738 if (!Sub) 7739 return ExprError(); 7740 7741 if (CheckBooleanCondition(Sub, Loc)) { 7742 Sub->Destroy(Context); 7743 return ExprError(); 7744 } 7745 7746 return Owned(Sub); 7747} 7748