SemaExpr.cpp revision a43dea209d7c936286e7f1099fde4e9dae27f1a1
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, 0, 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 if (Context.hasSameUnqualifiedType(exprType, Context.OverloadTy)) { 2031 Diag(OpLoc, diag::err_sizeof_alignof_overloaded_function_type) 2032 << !isSizeof << ExprRange; 2033 return true; 2034 } 2035 2036 return false; 2037} 2038 2039bool Sema::CheckAlignOfExpr(Expr *E, SourceLocation OpLoc, 2040 const SourceRange &ExprRange) { 2041 E = E->IgnoreParens(); 2042 2043 // alignof decl is always ok. 2044 if (isa<DeclRefExpr>(E)) 2045 return false; 2046 2047 // Cannot know anything else if the expression is dependent. 2048 if (E->isTypeDependent()) 2049 return false; 2050 2051 if (E->getBitField()) { 2052 Diag(OpLoc, diag::err_sizeof_alignof_bitfield) << 1 << ExprRange; 2053 return true; 2054 } 2055 2056 // Alignment of a field access is always okay, so long as it isn't a 2057 // bit-field. 2058 if (MemberExpr *ME = dyn_cast<MemberExpr>(E)) 2059 if (isa<FieldDecl>(ME->getMemberDecl())) 2060 return false; 2061 2062 return CheckSizeOfAlignOfOperand(E->getType(), OpLoc, ExprRange, false); 2063} 2064 2065/// \brief Build a sizeof or alignof expression given a type operand. 2066Action::OwningExprResult 2067Sema::CreateSizeOfAlignOfExpr(TypeSourceInfo *TInfo, 2068 SourceLocation OpLoc, 2069 bool isSizeOf, SourceRange R) { 2070 if (!TInfo) 2071 return ExprError(); 2072 2073 QualType T = TInfo->getType(); 2074 2075 if (!T->isDependentType() && 2076 CheckSizeOfAlignOfOperand(T, OpLoc, R, isSizeOf)) 2077 return ExprError(); 2078 2079 // C99 6.5.3.4p4: the type (an unsigned integer type) is size_t. 2080 return Owned(new (Context) SizeOfAlignOfExpr(isSizeOf, TInfo, 2081 Context.getSizeType(), OpLoc, 2082 R.getEnd())); 2083} 2084 2085/// \brief Build a sizeof or alignof expression given an expression 2086/// operand. 2087Action::OwningExprResult 2088Sema::CreateSizeOfAlignOfExpr(Expr *E, SourceLocation OpLoc, 2089 bool isSizeOf, SourceRange R) { 2090 // Verify that the operand is valid. 2091 bool isInvalid = false; 2092 if (E->isTypeDependent()) { 2093 // Delay type-checking for type-dependent expressions. 2094 } else if (!isSizeOf) { 2095 isInvalid = CheckAlignOfExpr(E, OpLoc, R); 2096 } else if (E->getBitField()) { // C99 6.5.3.4p1. 2097 Diag(OpLoc, diag::err_sizeof_alignof_bitfield) << 0; 2098 isInvalid = true; 2099 } else { 2100 isInvalid = CheckSizeOfAlignOfOperand(E->getType(), OpLoc, R, true); 2101 } 2102 2103 if (isInvalid) 2104 return ExprError(); 2105 2106 // C99 6.5.3.4p4: the type (an unsigned integer type) is size_t. 2107 return Owned(new (Context) SizeOfAlignOfExpr(isSizeOf, E, 2108 Context.getSizeType(), OpLoc, 2109 R.getEnd())); 2110} 2111 2112/// ActOnSizeOfAlignOfExpr - Handle @c sizeof(type) and @c sizeof @c expr and 2113/// the same for @c alignof and @c __alignof 2114/// Note that the ArgRange is invalid if isType is false. 2115Action::OwningExprResult 2116Sema::ActOnSizeOfAlignOfExpr(SourceLocation OpLoc, bool isSizeof, bool isType, 2117 void *TyOrEx, const SourceRange &ArgRange) { 2118 // If error parsing type, ignore. 2119 if (TyOrEx == 0) return ExprError(); 2120 2121 if (isType) { 2122 TypeSourceInfo *TInfo; 2123 (void) GetTypeFromParser(TyOrEx, &TInfo); 2124 return CreateSizeOfAlignOfExpr(TInfo, OpLoc, isSizeof, ArgRange); 2125 } 2126 2127 Expr *ArgEx = (Expr *)TyOrEx; 2128 Action::OwningExprResult Result 2129 = CreateSizeOfAlignOfExpr(ArgEx, OpLoc, isSizeof, ArgEx->getSourceRange()); 2130 2131 if (Result.isInvalid()) 2132 DeleteExpr(ArgEx); 2133 2134 return move(Result); 2135} 2136 2137QualType Sema::CheckRealImagOperand(Expr *&V, SourceLocation Loc, bool isReal) { 2138 if (V->isTypeDependent()) 2139 return Context.DependentTy; 2140 2141 // These operators return the element type of a complex type. 2142 if (const ComplexType *CT = V->getType()->getAs<ComplexType>()) 2143 return CT->getElementType(); 2144 2145 // Otherwise they pass through real integer and floating point types here. 2146 if (V->getType()->isArithmeticType()) 2147 return V->getType(); 2148 2149 // Reject anything else. 2150 Diag(Loc, diag::err_realimag_invalid_type) << V->getType() 2151 << (isReal ? "__real" : "__imag"); 2152 return QualType(); 2153} 2154 2155 2156 2157Action::OwningExprResult 2158Sema::ActOnPostfixUnaryOp(Scope *S, SourceLocation OpLoc, 2159 tok::TokenKind Kind, ExprArg Input) { 2160 UnaryOperator::Opcode Opc; 2161 switch (Kind) { 2162 default: assert(0 && "Unknown unary op!"); 2163 case tok::plusplus: Opc = UnaryOperator::PostInc; break; 2164 case tok::minusminus: Opc = UnaryOperator::PostDec; break; 2165 } 2166 2167 return BuildUnaryOp(S, OpLoc, Opc, move(Input)); 2168} 2169 2170Action::OwningExprResult 2171Sema::ActOnArraySubscriptExpr(Scope *S, ExprArg Base, SourceLocation LLoc, 2172 ExprArg Idx, SourceLocation RLoc) { 2173 // Since this might be a postfix expression, get rid of ParenListExprs. 2174 Base = MaybeConvertParenListExprToParenExpr(S, move(Base)); 2175 2176 Expr *LHSExp = static_cast<Expr*>(Base.get()), 2177 *RHSExp = static_cast<Expr*>(Idx.get()); 2178 2179 if (getLangOptions().CPlusPlus && 2180 (LHSExp->isTypeDependent() || RHSExp->isTypeDependent())) { 2181 Base.release(); 2182 Idx.release(); 2183 return Owned(new (Context) ArraySubscriptExpr(LHSExp, RHSExp, 2184 Context.DependentTy, RLoc)); 2185 } 2186 2187 if (getLangOptions().CPlusPlus && 2188 (LHSExp->getType()->isRecordType() || 2189 LHSExp->getType()->isEnumeralType() || 2190 RHSExp->getType()->isRecordType() || 2191 RHSExp->getType()->isEnumeralType())) { 2192 return CreateOverloadedArraySubscriptExpr(LLoc, RLoc, move(Base),move(Idx)); 2193 } 2194 2195 return CreateBuiltinArraySubscriptExpr(move(Base), LLoc, move(Idx), RLoc); 2196} 2197 2198 2199Action::OwningExprResult 2200Sema::CreateBuiltinArraySubscriptExpr(ExprArg Base, SourceLocation LLoc, 2201 ExprArg Idx, SourceLocation RLoc) { 2202 Expr *LHSExp = static_cast<Expr*>(Base.get()); 2203 Expr *RHSExp = static_cast<Expr*>(Idx.get()); 2204 2205 // Perform default conversions. 2206 if (!LHSExp->getType()->getAs<VectorType>()) 2207 DefaultFunctionArrayLvalueConversion(LHSExp); 2208 DefaultFunctionArrayLvalueConversion(RHSExp); 2209 2210 QualType LHSTy = LHSExp->getType(), RHSTy = RHSExp->getType(); 2211 2212 // C99 6.5.2.1p2: the expression e1[e2] is by definition precisely equivalent 2213 // to the expression *((e1)+(e2)). This means the array "Base" may actually be 2214 // in the subscript position. As a result, we need to derive the array base 2215 // and index from the expression types. 2216 Expr *BaseExpr, *IndexExpr; 2217 QualType ResultType; 2218 if (LHSTy->isDependentType() || RHSTy->isDependentType()) { 2219 BaseExpr = LHSExp; 2220 IndexExpr = RHSExp; 2221 ResultType = Context.DependentTy; 2222 } else if (const PointerType *PTy = LHSTy->getAs<PointerType>()) { 2223 BaseExpr = LHSExp; 2224 IndexExpr = RHSExp; 2225 ResultType = PTy->getPointeeType(); 2226 } else if (const PointerType *PTy = RHSTy->getAs<PointerType>()) { 2227 // Handle the uncommon case of "123[Ptr]". 2228 BaseExpr = RHSExp; 2229 IndexExpr = LHSExp; 2230 ResultType = PTy->getPointeeType(); 2231 } else if (const ObjCObjectPointerType *PTy = 2232 LHSTy->getAs<ObjCObjectPointerType>()) { 2233 BaseExpr = LHSExp; 2234 IndexExpr = RHSExp; 2235 ResultType = PTy->getPointeeType(); 2236 } else if (const ObjCObjectPointerType *PTy = 2237 RHSTy->getAs<ObjCObjectPointerType>()) { 2238 // Handle the uncommon case of "123[Ptr]". 2239 BaseExpr = RHSExp; 2240 IndexExpr = LHSExp; 2241 ResultType = PTy->getPointeeType(); 2242 } else if (const VectorType *VTy = LHSTy->getAs<VectorType>()) { 2243 BaseExpr = LHSExp; // vectors: V[123] 2244 IndexExpr = RHSExp; 2245 2246 // FIXME: need to deal with const... 2247 ResultType = VTy->getElementType(); 2248 } else if (LHSTy->isArrayType()) { 2249 // If we see an array that wasn't promoted by 2250 // DefaultFunctionArrayLvalueConversion, it must be an array that 2251 // wasn't promoted because of the C90 rule that doesn't 2252 // allow promoting non-lvalue arrays. Warn, then 2253 // force the promotion here. 2254 Diag(LHSExp->getLocStart(), diag::ext_subscript_non_lvalue) << 2255 LHSExp->getSourceRange(); 2256 ImpCastExprToType(LHSExp, Context.getArrayDecayedType(LHSTy), 2257 CastExpr::CK_ArrayToPointerDecay); 2258 LHSTy = LHSExp->getType(); 2259 2260 BaseExpr = LHSExp; 2261 IndexExpr = RHSExp; 2262 ResultType = LHSTy->getAs<PointerType>()->getPointeeType(); 2263 } else if (RHSTy->isArrayType()) { 2264 // Same as previous, except for 123[f().a] case 2265 Diag(RHSExp->getLocStart(), diag::ext_subscript_non_lvalue) << 2266 RHSExp->getSourceRange(); 2267 ImpCastExprToType(RHSExp, Context.getArrayDecayedType(RHSTy), 2268 CastExpr::CK_ArrayToPointerDecay); 2269 RHSTy = RHSExp->getType(); 2270 2271 BaseExpr = RHSExp; 2272 IndexExpr = LHSExp; 2273 ResultType = RHSTy->getAs<PointerType>()->getPointeeType(); 2274 } else { 2275 return ExprError(Diag(LLoc, diag::err_typecheck_subscript_value) 2276 << LHSExp->getSourceRange() << RHSExp->getSourceRange()); 2277 } 2278 // C99 6.5.2.1p1 2279 if (!(IndexExpr->getType()->isIntegerType() && 2280 IndexExpr->getType()->isScalarType()) && !IndexExpr->isTypeDependent()) 2281 return ExprError(Diag(LLoc, diag::err_typecheck_subscript_not_integer) 2282 << IndexExpr->getSourceRange()); 2283 2284 if ((IndexExpr->getType()->isSpecificBuiltinType(BuiltinType::Char_S) || 2285 IndexExpr->getType()->isSpecificBuiltinType(BuiltinType::Char_U)) 2286 && !IndexExpr->isTypeDependent()) 2287 Diag(LLoc, diag::warn_subscript_is_char) << IndexExpr->getSourceRange(); 2288 2289 // C99 6.5.2.1p1: "shall have type "pointer to *object* type". Similarly, 2290 // C++ [expr.sub]p1: The type "T" shall be a completely-defined object 2291 // type. Note that Functions are not objects, and that (in C99 parlance) 2292 // incomplete types are not object types. 2293 if (ResultType->isFunctionType()) { 2294 Diag(BaseExpr->getLocStart(), diag::err_subscript_function_type) 2295 << ResultType << BaseExpr->getSourceRange(); 2296 return ExprError(); 2297 } 2298 2299 if (!ResultType->isDependentType() && 2300 RequireCompleteType(LLoc, ResultType, 2301 PDiag(diag::err_subscript_incomplete_type) 2302 << BaseExpr->getSourceRange())) 2303 return ExprError(); 2304 2305 // Diagnose bad cases where we step over interface counts. 2306 if (ResultType->isObjCObjectType() && LangOpts.ObjCNonFragileABI) { 2307 Diag(LLoc, diag::err_subscript_nonfragile_interface) 2308 << ResultType << BaseExpr->getSourceRange(); 2309 return ExprError(); 2310 } 2311 2312 Base.release(); 2313 Idx.release(); 2314 return Owned(new (Context) ArraySubscriptExpr(LHSExp, RHSExp, 2315 ResultType, RLoc)); 2316} 2317 2318QualType Sema:: 2319CheckExtVectorComponent(QualType baseType, SourceLocation OpLoc, 2320 const IdentifierInfo *CompName, 2321 SourceLocation CompLoc) { 2322 // FIXME: Share logic with ExtVectorElementExpr::containsDuplicateElements, 2323 // see FIXME there. 2324 // 2325 // FIXME: This logic can be greatly simplified by splitting it along 2326 // halving/not halving and reworking the component checking. 2327 const ExtVectorType *vecType = baseType->getAs<ExtVectorType>(); 2328 2329 // The vector accessor can't exceed the number of elements. 2330 const char *compStr = CompName->getNameStart(); 2331 2332 // This flag determines whether or not the component is one of the four 2333 // special names that indicate a subset of exactly half the elements are 2334 // to be selected. 2335 bool HalvingSwizzle = false; 2336 2337 // This flag determines whether or not CompName has an 's' char prefix, 2338 // indicating that it is a string of hex values to be used as vector indices. 2339 bool HexSwizzle = *compStr == 's' || *compStr == 'S'; 2340 2341 // Check that we've found one of the special components, or that the component 2342 // names must come from the same set. 2343 if (!strcmp(compStr, "hi") || !strcmp(compStr, "lo") || 2344 !strcmp(compStr, "even") || !strcmp(compStr, "odd")) { 2345 HalvingSwizzle = true; 2346 } else if (vecType->getPointAccessorIdx(*compStr) != -1) { 2347 do 2348 compStr++; 2349 while (*compStr && vecType->getPointAccessorIdx(*compStr) != -1); 2350 } else if (HexSwizzle || vecType->getNumericAccessorIdx(*compStr) != -1) { 2351 do 2352 compStr++; 2353 while (*compStr && vecType->getNumericAccessorIdx(*compStr) != -1); 2354 } 2355 2356 if (!HalvingSwizzle && *compStr) { 2357 // We didn't get to the end of the string. This means the component names 2358 // didn't come from the same set *or* we encountered an illegal name. 2359 Diag(OpLoc, diag::err_ext_vector_component_name_illegal) 2360 << std::string(compStr,compStr+1) << SourceRange(CompLoc); 2361 return QualType(); 2362 } 2363 2364 // Ensure no component accessor exceeds the width of the vector type it 2365 // operates on. 2366 if (!HalvingSwizzle) { 2367 compStr = CompName->getNameStart(); 2368 2369 if (HexSwizzle) 2370 compStr++; 2371 2372 while (*compStr) { 2373 if (!vecType->isAccessorWithinNumElements(*compStr++)) { 2374 Diag(OpLoc, diag::err_ext_vector_component_exceeds_length) 2375 << baseType << SourceRange(CompLoc); 2376 return QualType(); 2377 } 2378 } 2379 } 2380 2381 // The component accessor looks fine - now we need to compute the actual type. 2382 // The vector type is implied by the component accessor. For example, 2383 // vec4.b is a float, vec4.xy is a vec2, vec4.rgb is a vec3, etc. 2384 // vec4.s0 is a float, vec4.s23 is a vec3, etc. 2385 // vec4.hi, vec4.lo, vec4.e, and vec4.o all return vec2. 2386 unsigned CompSize = HalvingSwizzle ? (vecType->getNumElements() + 1) / 2 2387 : CompName->getLength(); 2388 if (HexSwizzle) 2389 CompSize--; 2390 2391 if (CompSize == 1) 2392 return vecType->getElementType(); 2393 2394 QualType VT = Context.getExtVectorType(vecType->getElementType(), CompSize); 2395 // Now look up the TypeDefDecl from the vector type. Without this, 2396 // diagostics look bad. We want extended vector types to appear built-in. 2397 for (unsigned i = 0, E = ExtVectorDecls.size(); i != E; ++i) { 2398 if (ExtVectorDecls[i]->getUnderlyingType() == VT) 2399 return Context.getTypedefType(ExtVectorDecls[i]); 2400 } 2401 return VT; // should never get here (a typedef type should always be found). 2402} 2403 2404static Decl *FindGetterNameDeclFromProtocolList(const ObjCProtocolDecl*PDecl, 2405 IdentifierInfo *Member, 2406 const Selector &Sel, 2407 ASTContext &Context) { 2408 2409 if (ObjCPropertyDecl *PD = PDecl->FindPropertyDeclaration(Member)) 2410 return PD; 2411 if (ObjCMethodDecl *OMD = PDecl->getInstanceMethod(Sel)) 2412 return OMD; 2413 2414 for (ObjCProtocolDecl::protocol_iterator I = PDecl->protocol_begin(), 2415 E = PDecl->protocol_end(); I != E; ++I) { 2416 if (Decl *D = FindGetterNameDeclFromProtocolList(*I, Member, Sel, 2417 Context)) 2418 return D; 2419 } 2420 return 0; 2421} 2422 2423static Decl *FindGetterNameDecl(const ObjCObjectPointerType *QIdTy, 2424 IdentifierInfo *Member, 2425 const Selector &Sel, 2426 ASTContext &Context) { 2427 // Check protocols on qualified interfaces. 2428 Decl *GDecl = 0; 2429 for (ObjCObjectPointerType::qual_iterator I = QIdTy->qual_begin(), 2430 E = QIdTy->qual_end(); I != E; ++I) { 2431 if (ObjCPropertyDecl *PD = (*I)->FindPropertyDeclaration(Member)) { 2432 GDecl = PD; 2433 break; 2434 } 2435 // Also must look for a getter name which uses property syntax. 2436 if (ObjCMethodDecl *OMD = (*I)->getInstanceMethod(Sel)) { 2437 GDecl = OMD; 2438 break; 2439 } 2440 } 2441 if (!GDecl) { 2442 for (ObjCObjectPointerType::qual_iterator I = QIdTy->qual_begin(), 2443 E = QIdTy->qual_end(); I != E; ++I) { 2444 // Search in the protocol-qualifier list of current protocol. 2445 GDecl = FindGetterNameDeclFromProtocolList(*I, Member, Sel, Context); 2446 if (GDecl) 2447 return GDecl; 2448 } 2449 } 2450 return GDecl; 2451} 2452 2453Sema::OwningExprResult 2454Sema::ActOnDependentMemberExpr(ExprArg Base, QualType BaseType, 2455 bool IsArrow, SourceLocation OpLoc, 2456 const CXXScopeSpec &SS, 2457 NamedDecl *FirstQualifierInScope, 2458 DeclarationName Name, SourceLocation NameLoc, 2459 const TemplateArgumentListInfo *TemplateArgs) { 2460 Expr *BaseExpr = Base.takeAs<Expr>(); 2461 2462 // Even in dependent contexts, try to diagnose base expressions with 2463 // obviously wrong types, e.g.: 2464 // 2465 // T* t; 2466 // t.f; 2467 // 2468 // In Obj-C++, however, the above expression is valid, since it could be 2469 // accessing the 'f' property if T is an Obj-C interface. The extra check 2470 // allows this, while still reporting an error if T is a struct pointer. 2471 if (!IsArrow) { 2472 const PointerType *PT = BaseType->getAs<PointerType>(); 2473 if (PT && (!getLangOptions().ObjC1 || 2474 PT->getPointeeType()->isRecordType())) { 2475 assert(BaseExpr && "cannot happen with implicit member accesses"); 2476 Diag(NameLoc, diag::err_typecheck_member_reference_struct_union) 2477 << BaseType << BaseExpr->getSourceRange(); 2478 return ExprError(); 2479 } 2480 } 2481 2482 assert(BaseType->isDependentType() || Name.isDependentName() || 2483 isDependentScopeSpecifier(SS)); 2484 2485 // Get the type being accessed in BaseType. If this is an arrow, the BaseExpr 2486 // must have pointer type, and the accessed type is the pointee. 2487 return Owned(CXXDependentScopeMemberExpr::Create(Context, BaseExpr, BaseType, 2488 IsArrow, OpLoc, 2489 static_cast<NestedNameSpecifier*>(SS.getScopeRep()), 2490 SS.getRange(), 2491 FirstQualifierInScope, 2492 Name, NameLoc, 2493 TemplateArgs)); 2494} 2495 2496/// We know that the given qualified member reference points only to 2497/// declarations which do not belong to the static type of the base 2498/// expression. Diagnose the problem. 2499static void DiagnoseQualifiedMemberReference(Sema &SemaRef, 2500 Expr *BaseExpr, 2501 QualType BaseType, 2502 const CXXScopeSpec &SS, 2503 const LookupResult &R) { 2504 // If this is an implicit member access, use a different set of 2505 // diagnostics. 2506 if (!BaseExpr) 2507 return DiagnoseInstanceReference(SemaRef, SS, R); 2508 2509 SemaRef.Diag(R.getNameLoc(), diag::err_qualified_member_of_unrelated) 2510 << SS.getRange() << R.getRepresentativeDecl() << BaseType; 2511} 2512 2513// Check whether the declarations we found through a nested-name 2514// specifier in a member expression are actually members of the base 2515// type. The restriction here is: 2516// 2517// C++ [expr.ref]p2: 2518// ... In these cases, the id-expression shall name a 2519// member of the class or of one of its base classes. 2520// 2521// So it's perfectly legitimate for the nested-name specifier to name 2522// an unrelated class, and for us to find an overload set including 2523// decls from classes which are not superclasses, as long as the decl 2524// we actually pick through overload resolution is from a superclass. 2525bool Sema::CheckQualifiedMemberReference(Expr *BaseExpr, 2526 QualType BaseType, 2527 const CXXScopeSpec &SS, 2528 const LookupResult &R) { 2529 const RecordType *BaseRT = BaseType->getAs<RecordType>(); 2530 if (!BaseRT) { 2531 // We can't check this yet because the base type is still 2532 // dependent. 2533 assert(BaseType->isDependentType()); 2534 return false; 2535 } 2536 CXXRecordDecl *BaseRecord = cast<CXXRecordDecl>(BaseRT->getDecl()); 2537 2538 for (LookupResult::iterator I = R.begin(), E = R.end(); I != E; ++I) { 2539 // If this is an implicit member reference and we find a 2540 // non-instance member, it's not an error. 2541 if (!BaseExpr && !(*I)->isCXXInstanceMember()) 2542 return false; 2543 2544 // Note that we use the DC of the decl, not the underlying decl. 2545 CXXRecordDecl *RecordD = cast<CXXRecordDecl>((*I)->getDeclContext()); 2546 while (RecordD->isAnonymousStructOrUnion()) 2547 RecordD = cast<CXXRecordDecl>(RecordD->getParent()); 2548 2549 llvm::SmallPtrSet<CXXRecordDecl*,4> MemberRecord; 2550 MemberRecord.insert(RecordD->getCanonicalDecl()); 2551 2552 if (!IsProvablyNotDerivedFrom(*this, BaseRecord, MemberRecord)) 2553 return false; 2554 } 2555 2556 DiagnoseQualifiedMemberReference(*this, BaseExpr, BaseType, SS, R); 2557 return true; 2558} 2559 2560static bool 2561LookupMemberExprInRecord(Sema &SemaRef, LookupResult &R, 2562 SourceRange BaseRange, const RecordType *RTy, 2563 SourceLocation OpLoc, CXXScopeSpec &SS) { 2564 RecordDecl *RDecl = RTy->getDecl(); 2565 if (SemaRef.RequireCompleteType(OpLoc, QualType(RTy, 0), 2566 SemaRef.PDiag(diag::err_typecheck_incomplete_tag) 2567 << BaseRange)) 2568 return true; 2569 2570 DeclContext *DC = RDecl; 2571 if (SS.isSet()) { 2572 // If the member name was a qualified-id, look into the 2573 // nested-name-specifier. 2574 DC = SemaRef.computeDeclContext(SS, false); 2575 2576 if (SemaRef.RequireCompleteDeclContext(SS, DC)) { 2577 SemaRef.Diag(SS.getRange().getEnd(), diag::err_typecheck_incomplete_tag) 2578 << SS.getRange() << DC; 2579 return true; 2580 } 2581 2582 assert(DC && "Cannot handle non-computable dependent contexts in lookup"); 2583 2584 if (!isa<TypeDecl>(DC)) { 2585 SemaRef.Diag(R.getNameLoc(), diag::err_qualified_member_nonclass) 2586 << DC << SS.getRange(); 2587 return true; 2588 } 2589 } 2590 2591 // The record definition is complete, now look up the member. 2592 SemaRef.LookupQualifiedName(R, DC); 2593 2594 if (!R.empty()) 2595 return false; 2596 2597 // We didn't find anything with the given name, so try to correct 2598 // for typos. 2599 DeclarationName Name = R.getLookupName(); 2600 if (SemaRef.CorrectTypo(R, 0, &SS, DC, false, Sema::CTC_MemberLookup) && 2601 !R.empty() && 2602 (isa<ValueDecl>(*R.begin()) || isa<FunctionTemplateDecl>(*R.begin()))) { 2603 SemaRef.Diag(R.getNameLoc(), diag::err_no_member_suggest) 2604 << Name << DC << R.getLookupName() << SS.getRange() 2605 << FixItHint::CreateReplacement(R.getNameLoc(), 2606 R.getLookupName().getAsString()); 2607 if (NamedDecl *ND = R.getAsSingle<NamedDecl>()) 2608 SemaRef.Diag(ND->getLocation(), diag::note_previous_decl) 2609 << ND->getDeclName(); 2610 return false; 2611 } else { 2612 R.clear(); 2613 } 2614 2615 return false; 2616} 2617 2618Sema::OwningExprResult 2619Sema::BuildMemberReferenceExpr(ExprArg BaseArg, QualType BaseType, 2620 SourceLocation OpLoc, bool IsArrow, 2621 CXXScopeSpec &SS, 2622 NamedDecl *FirstQualifierInScope, 2623 DeclarationName Name, SourceLocation NameLoc, 2624 const TemplateArgumentListInfo *TemplateArgs) { 2625 Expr *Base = BaseArg.takeAs<Expr>(); 2626 2627 if (BaseType->isDependentType() || 2628 (SS.isSet() && isDependentScopeSpecifier(SS))) 2629 return ActOnDependentMemberExpr(ExprArg(*this, Base), BaseType, 2630 IsArrow, OpLoc, 2631 SS, FirstQualifierInScope, 2632 Name, NameLoc, 2633 TemplateArgs); 2634 2635 LookupResult R(*this, Name, NameLoc, LookupMemberName); 2636 2637 // Implicit member accesses. 2638 if (!Base) { 2639 QualType RecordTy = BaseType; 2640 if (IsArrow) RecordTy = RecordTy->getAs<PointerType>()->getPointeeType(); 2641 if (LookupMemberExprInRecord(*this, R, SourceRange(), 2642 RecordTy->getAs<RecordType>(), 2643 OpLoc, SS)) 2644 return ExprError(); 2645 2646 // Explicit member accesses. 2647 } else { 2648 OwningExprResult Result = 2649 LookupMemberExpr(R, Base, IsArrow, OpLoc, 2650 SS, /*ObjCImpDecl*/ DeclPtrTy()); 2651 2652 if (Result.isInvalid()) { 2653 Owned(Base); 2654 return ExprError(); 2655 } 2656 2657 if (Result.get()) 2658 return move(Result); 2659 2660 // LookupMemberExpr can modify Base, and thus change BaseType 2661 BaseType = Base->getType(); 2662 } 2663 2664 return BuildMemberReferenceExpr(ExprArg(*this, Base), BaseType, 2665 OpLoc, IsArrow, SS, FirstQualifierInScope, 2666 R, TemplateArgs); 2667} 2668 2669Sema::OwningExprResult 2670Sema::BuildMemberReferenceExpr(ExprArg Base, QualType BaseExprType, 2671 SourceLocation OpLoc, bool IsArrow, 2672 const CXXScopeSpec &SS, 2673 NamedDecl *FirstQualifierInScope, 2674 LookupResult &R, 2675 const TemplateArgumentListInfo *TemplateArgs, 2676 bool SuppressQualifierCheck) { 2677 Expr *BaseExpr = Base.takeAs<Expr>(); 2678 QualType BaseType = BaseExprType; 2679 if (IsArrow) { 2680 assert(BaseType->isPointerType()); 2681 BaseType = BaseType->getAs<PointerType>()->getPointeeType(); 2682 } 2683 R.setBaseObjectType(BaseType); 2684 2685 NestedNameSpecifier *Qualifier = 2686 static_cast<NestedNameSpecifier*>(SS.getScopeRep()); 2687 DeclarationName MemberName = R.getLookupName(); 2688 SourceLocation MemberLoc = R.getNameLoc(); 2689 2690 if (R.isAmbiguous()) 2691 return ExprError(); 2692 2693 if (R.empty()) { 2694 // Rederive where we looked up. 2695 DeclContext *DC = (SS.isSet() 2696 ? computeDeclContext(SS, false) 2697 : BaseType->getAs<RecordType>()->getDecl()); 2698 2699 Diag(R.getNameLoc(), diag::err_no_member) 2700 << MemberName << DC 2701 << (BaseExpr ? BaseExpr->getSourceRange() : SourceRange()); 2702 return ExprError(); 2703 } 2704 2705 // Diagnose lookups that find only declarations from a non-base 2706 // type. This is possible for either qualified lookups (which may 2707 // have been qualified with an unrelated type) or implicit member 2708 // expressions (which were found with unqualified lookup and thus 2709 // may have come from an enclosing scope). Note that it's okay for 2710 // lookup to find declarations from a non-base type as long as those 2711 // aren't the ones picked by overload resolution. 2712 if ((SS.isSet() || !BaseExpr || 2713 (isa<CXXThisExpr>(BaseExpr) && 2714 cast<CXXThisExpr>(BaseExpr)->isImplicit())) && 2715 !SuppressQualifierCheck && 2716 CheckQualifiedMemberReference(BaseExpr, BaseType, SS, R)) 2717 return ExprError(); 2718 2719 // Construct an unresolved result if we in fact got an unresolved 2720 // result. 2721 if (R.isOverloadedResult() || R.isUnresolvableResult()) { 2722 bool Dependent = 2723 BaseExprType->isDependentType() || 2724 R.isUnresolvableResult() || 2725 OverloadExpr::ComputeDependence(R.begin(), R.end(), TemplateArgs); 2726 2727 // Suppress any lookup-related diagnostics; we'll do these when we 2728 // pick a member. 2729 R.suppressDiagnostics(); 2730 2731 UnresolvedMemberExpr *MemExpr 2732 = UnresolvedMemberExpr::Create(Context, Dependent, 2733 R.isUnresolvableResult(), 2734 BaseExpr, BaseExprType, 2735 IsArrow, OpLoc, 2736 Qualifier, SS.getRange(), 2737 MemberName, MemberLoc, 2738 TemplateArgs, R.begin(), R.end()); 2739 2740 return Owned(MemExpr); 2741 } 2742 2743 assert(R.isSingleResult()); 2744 DeclAccessPair FoundDecl = R.begin().getPair(); 2745 NamedDecl *MemberDecl = R.getFoundDecl(); 2746 2747 // FIXME: diagnose the presence of template arguments now. 2748 2749 // If the decl being referenced had an error, return an error for this 2750 // sub-expr without emitting another error, in order to avoid cascading 2751 // error cases. 2752 if (MemberDecl->isInvalidDecl()) 2753 return ExprError(); 2754 2755 // Handle the implicit-member-access case. 2756 if (!BaseExpr) { 2757 // If this is not an instance member, convert to a non-member access. 2758 if (!MemberDecl->isCXXInstanceMember()) 2759 return BuildDeclarationNameExpr(SS, R.getNameLoc(), MemberDecl); 2760 2761 SourceLocation Loc = R.getNameLoc(); 2762 if (SS.getRange().isValid()) 2763 Loc = SS.getRange().getBegin(); 2764 BaseExpr = new (Context) CXXThisExpr(Loc, BaseExprType,/*isImplicit=*/true); 2765 } 2766 2767 bool ShouldCheckUse = true; 2768 if (CXXMethodDecl *MD = dyn_cast<CXXMethodDecl>(MemberDecl)) { 2769 // Don't diagnose the use of a virtual member function unless it's 2770 // explicitly qualified. 2771 if (MD->isVirtual() && !SS.isSet()) 2772 ShouldCheckUse = false; 2773 } 2774 2775 // Check the use of this member. 2776 if (ShouldCheckUse && DiagnoseUseOfDecl(MemberDecl, MemberLoc)) { 2777 Owned(BaseExpr); 2778 return ExprError(); 2779 } 2780 2781 if (FieldDecl *FD = dyn_cast<FieldDecl>(MemberDecl)) { 2782 // We may have found a field within an anonymous union or struct 2783 // (C++ [class.union]). 2784 if (cast<RecordDecl>(FD->getDeclContext())->isAnonymousStructOrUnion() && 2785 !BaseType->getAs<RecordType>()->getDecl()->isAnonymousStructOrUnion()) 2786 return BuildAnonymousStructUnionMemberReference(MemberLoc, FD, 2787 BaseExpr, OpLoc); 2788 2789 // Figure out the type of the member; see C99 6.5.2.3p3, C++ [expr.ref] 2790 QualType MemberType = FD->getType(); 2791 if (const ReferenceType *Ref = MemberType->getAs<ReferenceType>()) 2792 MemberType = Ref->getPointeeType(); 2793 else { 2794 Qualifiers BaseQuals = BaseType.getQualifiers(); 2795 BaseQuals.removeObjCGCAttr(); 2796 if (FD->isMutable()) BaseQuals.removeConst(); 2797 2798 Qualifiers MemberQuals 2799 = Context.getCanonicalType(MemberType).getQualifiers(); 2800 2801 Qualifiers Combined = BaseQuals + MemberQuals; 2802 if (Combined != MemberQuals) 2803 MemberType = Context.getQualifiedType(MemberType, Combined); 2804 } 2805 2806 MarkDeclarationReferenced(MemberLoc, FD); 2807 if (PerformObjectMemberConversion(BaseExpr, Qualifier, FoundDecl, FD)) 2808 return ExprError(); 2809 return Owned(BuildMemberExpr(Context, BaseExpr, IsArrow, SS, 2810 FD, FoundDecl, MemberLoc, MemberType)); 2811 } 2812 2813 if (VarDecl *Var = dyn_cast<VarDecl>(MemberDecl)) { 2814 MarkDeclarationReferenced(MemberLoc, Var); 2815 return Owned(BuildMemberExpr(Context, BaseExpr, IsArrow, SS, 2816 Var, FoundDecl, MemberLoc, 2817 Var->getType().getNonReferenceType())); 2818 } 2819 2820 if (FunctionDecl *MemberFn = dyn_cast<FunctionDecl>(MemberDecl)) { 2821 MarkDeclarationReferenced(MemberLoc, MemberDecl); 2822 return Owned(BuildMemberExpr(Context, BaseExpr, IsArrow, SS, 2823 MemberFn, FoundDecl, MemberLoc, 2824 MemberFn->getType())); 2825 } 2826 2827 if (EnumConstantDecl *Enum = dyn_cast<EnumConstantDecl>(MemberDecl)) { 2828 MarkDeclarationReferenced(MemberLoc, MemberDecl); 2829 return Owned(BuildMemberExpr(Context, BaseExpr, IsArrow, SS, 2830 Enum, FoundDecl, MemberLoc, Enum->getType())); 2831 } 2832 2833 Owned(BaseExpr); 2834 2835 // We found something that we didn't expect. Complain. 2836 if (isa<TypeDecl>(MemberDecl)) 2837 Diag(MemberLoc,diag::err_typecheck_member_reference_type) 2838 << MemberName << BaseType << int(IsArrow); 2839 else 2840 Diag(MemberLoc, diag::err_typecheck_member_reference_unknown) 2841 << MemberName << BaseType << int(IsArrow); 2842 2843 Diag(MemberDecl->getLocation(), diag::note_member_declared_here) 2844 << MemberName; 2845 R.suppressDiagnostics(); 2846 return ExprError(); 2847} 2848 2849/// Look up the given member of the given non-type-dependent 2850/// expression. This can return in one of two ways: 2851/// * If it returns a sentinel null-but-valid result, the caller will 2852/// assume that lookup was performed and the results written into 2853/// the provided structure. It will take over from there. 2854/// * Otherwise, the returned expression will be produced in place of 2855/// an ordinary member expression. 2856/// 2857/// The ObjCImpDecl bit is a gross hack that will need to be properly 2858/// fixed for ObjC++. 2859Sema::OwningExprResult 2860Sema::LookupMemberExpr(LookupResult &R, Expr *&BaseExpr, 2861 bool &IsArrow, SourceLocation OpLoc, 2862 CXXScopeSpec &SS, 2863 DeclPtrTy ObjCImpDecl) { 2864 assert(BaseExpr && "no base expression"); 2865 2866 // Perform default conversions. 2867 DefaultFunctionArrayConversion(BaseExpr); 2868 2869 QualType BaseType = BaseExpr->getType(); 2870 assert(!BaseType->isDependentType()); 2871 2872 DeclarationName MemberName = R.getLookupName(); 2873 SourceLocation MemberLoc = R.getNameLoc(); 2874 2875 // If the user is trying to apply -> or . to a function pointer 2876 // type, it's probably because they forgot parentheses to call that 2877 // function. Suggest the addition of those parentheses, build the 2878 // call, and continue on. 2879 if (const PointerType *Ptr = BaseType->getAs<PointerType>()) { 2880 if (const FunctionProtoType *Fun 2881 = Ptr->getPointeeType()->getAs<FunctionProtoType>()) { 2882 QualType ResultTy = Fun->getResultType(); 2883 if (Fun->getNumArgs() == 0 && 2884 ((!IsArrow && ResultTy->isRecordType()) || 2885 (IsArrow && ResultTy->isPointerType() && 2886 ResultTy->getAs<PointerType>()->getPointeeType() 2887 ->isRecordType()))) { 2888 SourceLocation Loc = PP.getLocForEndOfToken(BaseExpr->getLocEnd()); 2889 Diag(Loc, diag::err_member_reference_needs_call) 2890 << QualType(Fun, 0) 2891 << FixItHint::CreateInsertion(Loc, "()"); 2892 2893 OwningExprResult NewBase 2894 = ActOnCallExpr(0, ExprArg(*this, BaseExpr), Loc, 2895 MultiExprArg(*this, 0, 0), 0, Loc); 2896 if (NewBase.isInvalid()) 2897 return ExprError(); 2898 2899 BaseExpr = NewBase.takeAs<Expr>(); 2900 DefaultFunctionArrayConversion(BaseExpr); 2901 BaseType = BaseExpr->getType(); 2902 } 2903 } 2904 } 2905 2906 // If this is an Objective-C pseudo-builtin and a definition is provided then 2907 // use that. 2908 if (BaseType->isObjCIdType()) { 2909 if (IsArrow) { 2910 // Handle the following exceptional case PObj->isa. 2911 if (const ObjCObjectPointerType *OPT = 2912 BaseType->getAs<ObjCObjectPointerType>()) { 2913 if (OPT->getObjectType()->isObjCId() && 2914 MemberName.getAsIdentifierInfo()->isStr("isa")) 2915 return Owned(new (Context) ObjCIsaExpr(BaseExpr, true, MemberLoc, 2916 Context.getObjCClassType())); 2917 } 2918 } 2919 // We have an 'id' type. Rather than fall through, we check if this 2920 // is a reference to 'isa'. 2921 if (BaseType != Context.ObjCIdRedefinitionType) { 2922 BaseType = Context.ObjCIdRedefinitionType; 2923 ImpCastExprToType(BaseExpr, BaseType, CastExpr::CK_BitCast); 2924 } 2925 } 2926 2927 // If this is an Objective-C pseudo-builtin and a definition is provided then 2928 // use that. 2929 if (Context.isObjCSelType(BaseType)) { 2930 // We have an 'SEL' type. Rather than fall through, we check if this 2931 // is a reference to 'sel_id'. 2932 if (BaseType != Context.ObjCSelRedefinitionType) { 2933 BaseType = Context.ObjCSelRedefinitionType; 2934 ImpCastExprToType(BaseExpr, BaseType, CastExpr::CK_BitCast); 2935 } 2936 } 2937 2938 assert(!BaseType.isNull() && "no type for member expression"); 2939 2940 // Handle properties on ObjC 'Class' types. 2941 if (!IsArrow && BaseType->isObjCClassType()) { 2942 // Also must look for a getter name which uses property syntax. 2943 IdentifierInfo *Member = MemberName.getAsIdentifierInfo(); 2944 Selector Sel = PP.getSelectorTable().getNullarySelector(Member); 2945 if (ObjCMethodDecl *MD = getCurMethodDecl()) { 2946 ObjCInterfaceDecl *IFace = MD->getClassInterface(); 2947 ObjCMethodDecl *Getter; 2948 // FIXME: need to also look locally in the implementation. 2949 if ((Getter = IFace->lookupClassMethod(Sel))) { 2950 // Check the use of this method. 2951 if (DiagnoseUseOfDecl(Getter, MemberLoc)) 2952 return ExprError(); 2953 } 2954 // If we found a getter then this may be a valid dot-reference, we 2955 // will look for the matching setter, in case it is needed. 2956 Selector SetterSel = 2957 SelectorTable::constructSetterName(PP.getIdentifierTable(), 2958 PP.getSelectorTable(), Member); 2959 ObjCMethodDecl *Setter = IFace->lookupClassMethod(SetterSel); 2960 if (!Setter) { 2961 // If this reference is in an @implementation, also check for 'private' 2962 // methods. 2963 Setter = IFace->lookupPrivateInstanceMethod(SetterSel); 2964 } 2965 // Look through local category implementations associated with the class. 2966 if (!Setter) 2967 Setter = IFace->getCategoryClassMethod(SetterSel); 2968 2969 if (Setter && DiagnoseUseOfDecl(Setter, MemberLoc)) 2970 return ExprError(); 2971 2972 if (Getter || Setter) { 2973 QualType PType; 2974 2975 if (Getter) 2976 PType = Getter->getResultType(); 2977 else 2978 // Get the expression type from Setter's incoming parameter. 2979 PType = (*(Setter->param_end() -1))->getType(); 2980 // FIXME: we must check that the setter has property type. 2981 return Owned(new (Context) ObjCImplicitSetterGetterRefExpr(Getter, 2982 PType, 2983 Setter, MemberLoc, BaseExpr)); 2984 } 2985 return ExprError(Diag(MemberLoc, diag::err_property_not_found) 2986 << MemberName << BaseType); 2987 } 2988 } 2989 2990 if (BaseType->isObjCClassType() && 2991 BaseType != Context.ObjCClassRedefinitionType) { 2992 BaseType = Context.ObjCClassRedefinitionType; 2993 ImpCastExprToType(BaseExpr, BaseType, CastExpr::CK_BitCast); 2994 } 2995 2996 if (IsArrow) { 2997 if (const PointerType *PT = BaseType->getAs<PointerType>()) 2998 BaseType = PT->getPointeeType(); 2999 else if (BaseType->isObjCObjectPointerType()) 3000 ; 3001 else if (BaseType->isRecordType()) { 3002 // Recover from arrow accesses to records, e.g.: 3003 // struct MyRecord foo; 3004 // foo->bar 3005 // This is actually well-formed in C++ if MyRecord has an 3006 // overloaded operator->, but that should have been dealt with 3007 // by now. 3008 Diag(OpLoc, diag::err_typecheck_member_reference_suggestion) 3009 << BaseType << int(IsArrow) << BaseExpr->getSourceRange() 3010 << FixItHint::CreateReplacement(OpLoc, "."); 3011 IsArrow = false; 3012 } else { 3013 Diag(MemberLoc, diag::err_typecheck_member_reference_arrow) 3014 << BaseType << BaseExpr->getSourceRange(); 3015 return ExprError(); 3016 } 3017 } else { 3018 // Recover from dot accesses to pointers, e.g.: 3019 // type *foo; 3020 // foo.bar 3021 // This is actually well-formed in two cases: 3022 // - 'type' is an Objective C type 3023 // - 'bar' is a pseudo-destructor name which happens to refer to 3024 // the appropriate pointer type 3025 if (MemberName.getNameKind() != DeclarationName::CXXDestructorName) { 3026 const PointerType *PT = BaseType->getAs<PointerType>(); 3027 if (PT && PT->getPointeeType()->isRecordType()) { 3028 Diag(OpLoc, diag::err_typecheck_member_reference_suggestion) 3029 << BaseType << int(IsArrow) << BaseExpr->getSourceRange() 3030 << FixItHint::CreateReplacement(OpLoc, "->"); 3031 BaseType = PT->getPointeeType(); 3032 IsArrow = true; 3033 } 3034 } 3035 } 3036 3037 // Handle field access to simple records. 3038 if (const RecordType *RTy = BaseType->getAs<RecordType>()) { 3039 if (LookupMemberExprInRecord(*this, R, BaseExpr->getSourceRange(), 3040 RTy, OpLoc, SS)) 3041 return ExprError(); 3042 return Owned((Expr*) 0); 3043 } 3044 3045 // Handle access to Objective-C instance variables, such as "Obj->ivar" and 3046 // (*Obj).ivar. 3047 if ((IsArrow && BaseType->isObjCObjectPointerType()) || 3048 (!IsArrow && BaseType->isObjCObjectType())) { 3049 const ObjCObjectPointerType *OPT = BaseType->getAs<ObjCObjectPointerType>(); 3050 ObjCInterfaceDecl *IDecl = 3051 OPT ? OPT->getInterfaceDecl() 3052 : BaseType->getAs<ObjCObjectType>()->getInterface(); 3053 if (IDecl) { 3054 IdentifierInfo *Member = MemberName.getAsIdentifierInfo(); 3055 3056 ObjCInterfaceDecl *ClassDeclared; 3057 ObjCIvarDecl *IV = IDecl->lookupInstanceVariable(Member, ClassDeclared); 3058 3059 if (!IV) { 3060 // Attempt to correct for typos in ivar names. 3061 LookupResult Res(*this, R.getLookupName(), R.getNameLoc(), 3062 LookupMemberName); 3063 if (CorrectTypo(Res, 0, 0, IDecl, false, CTC_MemberLookup) && 3064 (IV = Res.getAsSingle<ObjCIvarDecl>())) { 3065 Diag(R.getNameLoc(), 3066 diag::err_typecheck_member_reference_ivar_suggest) 3067 << IDecl->getDeclName() << MemberName << IV->getDeclName() 3068 << FixItHint::CreateReplacement(R.getNameLoc(), 3069 IV->getNameAsString()); 3070 Diag(IV->getLocation(), diag::note_previous_decl) 3071 << IV->getDeclName(); 3072 } 3073 } 3074 3075 if (IV) { 3076 // If the decl being referenced had an error, return an error for this 3077 // sub-expr without emitting another error, in order to avoid cascading 3078 // error cases. 3079 if (IV->isInvalidDecl()) 3080 return ExprError(); 3081 3082 // Check whether we can reference this field. 3083 if (DiagnoseUseOfDecl(IV, MemberLoc)) 3084 return ExprError(); 3085 if (IV->getAccessControl() != ObjCIvarDecl::Public && 3086 IV->getAccessControl() != ObjCIvarDecl::Package) { 3087 ObjCInterfaceDecl *ClassOfMethodDecl = 0; 3088 if (ObjCMethodDecl *MD = getCurMethodDecl()) 3089 ClassOfMethodDecl = MD->getClassInterface(); 3090 else if (ObjCImpDecl && getCurFunctionDecl()) { 3091 // Case of a c-function declared inside an objc implementation. 3092 // FIXME: For a c-style function nested inside an objc implementation 3093 // class, there is no implementation context available, so we pass 3094 // down the context as argument to this routine. Ideally, this context 3095 // need be passed down in the AST node and somehow calculated from the 3096 // AST for a function decl. 3097 Decl *ImplDecl = ObjCImpDecl.getAs<Decl>(); 3098 if (ObjCImplementationDecl *IMPD = 3099 dyn_cast<ObjCImplementationDecl>(ImplDecl)) 3100 ClassOfMethodDecl = IMPD->getClassInterface(); 3101 else if (ObjCCategoryImplDecl* CatImplClass = 3102 dyn_cast<ObjCCategoryImplDecl>(ImplDecl)) 3103 ClassOfMethodDecl = CatImplClass->getClassInterface(); 3104 } 3105 3106 if (IV->getAccessControl() == ObjCIvarDecl::Private) { 3107 if (ClassDeclared != IDecl || 3108 ClassOfMethodDecl != ClassDeclared) 3109 Diag(MemberLoc, diag::error_private_ivar_access) 3110 << IV->getDeclName(); 3111 } else if (!IDecl->isSuperClassOf(ClassOfMethodDecl)) 3112 // @protected 3113 Diag(MemberLoc, diag::error_protected_ivar_access) 3114 << IV->getDeclName(); 3115 } 3116 3117 return Owned(new (Context) ObjCIvarRefExpr(IV, IV->getType(), 3118 MemberLoc, BaseExpr, 3119 IsArrow)); 3120 } 3121 return ExprError(Diag(MemberLoc, diag::err_typecheck_member_reference_ivar) 3122 << IDecl->getDeclName() << MemberName 3123 << BaseExpr->getSourceRange()); 3124 } 3125 } 3126 // Handle properties on 'id' and qualified "id". 3127 if (!IsArrow && (BaseType->isObjCIdType() || 3128 BaseType->isObjCQualifiedIdType())) { 3129 const ObjCObjectPointerType *QIdTy = BaseType->getAs<ObjCObjectPointerType>(); 3130 IdentifierInfo *Member = MemberName.getAsIdentifierInfo(); 3131 3132 // Check protocols on qualified interfaces. 3133 Selector Sel = PP.getSelectorTable().getNullarySelector(Member); 3134 if (Decl *PMDecl = FindGetterNameDecl(QIdTy, Member, Sel, Context)) { 3135 if (ObjCPropertyDecl *PD = dyn_cast<ObjCPropertyDecl>(PMDecl)) { 3136 // Check the use of this declaration 3137 if (DiagnoseUseOfDecl(PD, MemberLoc)) 3138 return ExprError(); 3139 3140 return Owned(new (Context) ObjCPropertyRefExpr(PD, PD->getType(), 3141 MemberLoc, BaseExpr)); 3142 } 3143 if (ObjCMethodDecl *OMD = dyn_cast<ObjCMethodDecl>(PMDecl)) { 3144 // Check the use of this method. 3145 if (DiagnoseUseOfDecl(OMD, MemberLoc)) 3146 return ExprError(); 3147 3148 return Owned(ObjCMessageExpr::Create(Context, 3149 OMD->getResultType().getNonReferenceType(), 3150 OpLoc, BaseExpr, Sel, 3151 OMD, NULL, 0, MemberLoc)); 3152 } 3153 } 3154 3155 return ExprError(Diag(MemberLoc, diag::err_property_not_found) 3156 << MemberName << BaseType); 3157 } 3158 3159 // Handle Objective-C property access, which is "Obj.property" where Obj is a 3160 // pointer to a (potentially qualified) interface type. 3161 if (!IsArrow) 3162 if (const ObjCObjectPointerType *OPT = 3163 BaseType->getAsObjCInterfacePointerType()) 3164 return HandleExprPropertyRefExpr(OPT, BaseExpr, MemberName, MemberLoc); 3165 3166 // Handle the following exceptional case (*Obj).isa. 3167 if (!IsArrow && 3168 BaseType->isObjCObjectType() && 3169 BaseType->getAs<ObjCObjectType>()->isObjCId() && 3170 MemberName.getAsIdentifierInfo()->isStr("isa")) 3171 return Owned(new (Context) ObjCIsaExpr(BaseExpr, false, MemberLoc, 3172 Context.getObjCClassType())); 3173 3174 // Handle 'field access' to vectors, such as 'V.xx'. 3175 if (BaseType->isExtVectorType()) { 3176 IdentifierInfo *Member = MemberName.getAsIdentifierInfo(); 3177 QualType ret = CheckExtVectorComponent(BaseType, OpLoc, Member, MemberLoc); 3178 if (ret.isNull()) 3179 return ExprError(); 3180 return Owned(new (Context) ExtVectorElementExpr(ret, BaseExpr, *Member, 3181 MemberLoc)); 3182 } 3183 3184 Diag(MemberLoc, diag::err_typecheck_member_reference_struct_union) 3185 << BaseType << BaseExpr->getSourceRange(); 3186 3187 return ExprError(); 3188} 3189 3190/// The main callback when the parser finds something like 3191/// expression . [nested-name-specifier] identifier 3192/// expression -> [nested-name-specifier] identifier 3193/// where 'identifier' encompasses a fairly broad spectrum of 3194/// possibilities, including destructor and operator references. 3195/// 3196/// \param OpKind either tok::arrow or tok::period 3197/// \param HasTrailingLParen whether the next token is '(', which 3198/// is used to diagnose mis-uses of special members that can 3199/// only be called 3200/// \param ObjCImpDecl the current ObjC @implementation decl; 3201/// this is an ugly hack around the fact that ObjC @implementations 3202/// aren't properly put in the context chain 3203Sema::OwningExprResult Sema::ActOnMemberAccessExpr(Scope *S, ExprArg BaseArg, 3204 SourceLocation OpLoc, 3205 tok::TokenKind OpKind, 3206 CXXScopeSpec &SS, 3207 UnqualifiedId &Id, 3208 DeclPtrTy ObjCImpDecl, 3209 bool HasTrailingLParen) { 3210 if (SS.isSet() && SS.isInvalid()) 3211 return ExprError(); 3212 3213 TemplateArgumentListInfo TemplateArgsBuffer; 3214 3215 // Decompose the name into its component parts. 3216 DeclarationName Name; 3217 SourceLocation NameLoc; 3218 const TemplateArgumentListInfo *TemplateArgs; 3219 DecomposeUnqualifiedId(*this, Id, TemplateArgsBuffer, 3220 Name, NameLoc, TemplateArgs); 3221 3222 bool IsArrow = (OpKind == tok::arrow); 3223 3224 NamedDecl *FirstQualifierInScope 3225 = (!SS.isSet() ? 0 : FindFirstQualifierInScope(S, 3226 static_cast<NestedNameSpecifier*>(SS.getScopeRep()))); 3227 3228 // This is a postfix expression, so get rid of ParenListExprs. 3229 BaseArg = MaybeConvertParenListExprToParenExpr(S, move(BaseArg)); 3230 3231 Expr *Base = BaseArg.takeAs<Expr>(); 3232 OwningExprResult Result(*this); 3233 if (Base->getType()->isDependentType() || Name.isDependentName() || 3234 isDependentScopeSpecifier(SS)) { 3235 Result = ActOnDependentMemberExpr(ExprArg(*this, Base), Base->getType(), 3236 IsArrow, OpLoc, 3237 SS, FirstQualifierInScope, 3238 Name, NameLoc, 3239 TemplateArgs); 3240 } else { 3241 LookupResult R(*this, Name, NameLoc, LookupMemberName); 3242 if (TemplateArgs) { 3243 // Re-use the lookup done for the template name. 3244 DecomposeTemplateName(R, Id); 3245 3246 // Re-derive the naming class. 3247 if (SS.isSet()) { 3248 NestedNameSpecifier *Qualifier 3249 = static_cast<NestedNameSpecifier *>(SS.getScopeRep()); 3250 if (const Type *Ty = Qualifier->getAsType()) 3251 if (CXXRecordDecl *NamingClass = Ty->getAsCXXRecordDecl()) 3252 R.setNamingClass(NamingClass); 3253 } else { 3254 QualType BaseType = Base->getType(); 3255 if (const PointerType *Ptr = BaseType->getAs<PointerType>()) 3256 BaseType = Ptr->getPointeeType(); 3257 if (CXXRecordDecl *NamingClass = BaseType->getAsCXXRecordDecl()) 3258 R.setNamingClass(NamingClass); 3259 } 3260 } else { 3261 Result = LookupMemberExpr(R, Base, IsArrow, OpLoc, 3262 SS, ObjCImpDecl); 3263 3264 if (Result.isInvalid()) { 3265 Owned(Base); 3266 return ExprError(); 3267 } 3268 3269 if (Result.get()) { 3270 // The only way a reference to a destructor can be used is to 3271 // immediately call it, which falls into this case. If the 3272 // next token is not a '(', produce a diagnostic and build the 3273 // call now. 3274 if (!HasTrailingLParen && 3275 Id.getKind() == UnqualifiedId::IK_DestructorName) 3276 return DiagnoseDtorReference(NameLoc, move(Result)); 3277 3278 return move(Result); 3279 } 3280 } 3281 3282 Result = BuildMemberReferenceExpr(ExprArg(*this, Base), Base->getType(), 3283 OpLoc, IsArrow, SS, FirstQualifierInScope, 3284 R, TemplateArgs); 3285 } 3286 3287 return move(Result); 3288} 3289 3290Sema::OwningExprResult Sema::BuildCXXDefaultArgExpr(SourceLocation CallLoc, 3291 FunctionDecl *FD, 3292 ParmVarDecl *Param) { 3293 if (Param->hasUnparsedDefaultArg()) { 3294 Diag (CallLoc, 3295 diag::err_use_of_default_argument_to_function_declared_later) << 3296 FD << cast<CXXRecordDecl>(FD->getDeclContext())->getDeclName(); 3297 Diag(UnparsedDefaultArgLocs[Param], 3298 diag::note_default_argument_declared_here); 3299 } else { 3300 if (Param->hasUninstantiatedDefaultArg()) { 3301 Expr *UninstExpr = Param->getUninstantiatedDefaultArg(); 3302 3303 // Instantiate the expression. 3304 MultiLevelTemplateArgumentList ArgList 3305 = getTemplateInstantiationArgs(FD, 0, /*RelativeToPrimary=*/true); 3306 3307 InstantiatingTemplate Inst(*this, CallLoc, Param, 3308 ArgList.getInnermost().getFlatArgumentList(), 3309 ArgList.getInnermost().flat_size()); 3310 3311 OwningExprResult Result = SubstExpr(UninstExpr, ArgList); 3312 if (Result.isInvalid()) 3313 return ExprError(); 3314 3315 // Check the expression as an initializer for the parameter. 3316 InitializedEntity Entity 3317 = InitializedEntity::InitializeParameter(Param); 3318 InitializationKind Kind 3319 = InitializationKind::CreateCopy(Param->getLocation(), 3320 /*FIXME:EqualLoc*/UninstExpr->getSourceRange().getBegin()); 3321 Expr *ResultE = Result.takeAs<Expr>(); 3322 3323 InitializationSequence InitSeq(*this, Entity, Kind, &ResultE, 1); 3324 Result = InitSeq.Perform(*this, Entity, Kind, 3325 MultiExprArg(*this, (void**)&ResultE, 1)); 3326 if (Result.isInvalid()) 3327 return ExprError(); 3328 3329 // Build the default argument expression. 3330 return Owned(CXXDefaultArgExpr::Create(Context, CallLoc, Param, 3331 Result.takeAs<Expr>())); 3332 } 3333 3334 // If the default expression creates temporaries, we need to 3335 // push them to the current stack of expression temporaries so they'll 3336 // be properly destroyed. 3337 // FIXME: We should really be rebuilding the default argument with new 3338 // bound temporaries; see the comment in PR5810. 3339 for (unsigned i = 0, e = Param->getNumDefaultArgTemporaries(); i != e; ++i) 3340 ExprTemporaries.push_back(Param->getDefaultArgTemporary(i)); 3341 } 3342 3343 // We already type-checked the argument, so we know it works. 3344 return Owned(CXXDefaultArgExpr::Create(Context, CallLoc, Param)); 3345} 3346 3347/// ConvertArgumentsForCall - Converts the arguments specified in 3348/// Args/NumArgs to the parameter types of the function FDecl with 3349/// function prototype Proto. Call is the call expression itself, and 3350/// Fn is the function expression. For a C++ member function, this 3351/// routine does not attempt to convert the object argument. Returns 3352/// true if the call is ill-formed. 3353bool 3354Sema::ConvertArgumentsForCall(CallExpr *Call, Expr *Fn, 3355 FunctionDecl *FDecl, 3356 const FunctionProtoType *Proto, 3357 Expr **Args, unsigned NumArgs, 3358 SourceLocation RParenLoc) { 3359 // C99 6.5.2.2p7 - the arguments are implicitly converted, as if by 3360 // assignment, to the types of the corresponding parameter, ... 3361 unsigned NumArgsInProto = Proto->getNumArgs(); 3362 bool Invalid = false; 3363 3364 // If too few arguments are available (and we don't have default 3365 // arguments for the remaining parameters), don't make the call. 3366 if (NumArgs < NumArgsInProto) { 3367 if (!FDecl || NumArgs < FDecl->getMinRequiredArguments()) 3368 return Diag(RParenLoc, diag::err_typecheck_call_too_few_args) 3369 << Fn->getType()->isBlockPointerType() 3370 << NumArgsInProto << NumArgs << Fn->getSourceRange(); 3371 Call->setNumArgs(Context, NumArgsInProto); 3372 } 3373 3374 // If too many are passed and not variadic, error on the extras and drop 3375 // them. 3376 if (NumArgs > NumArgsInProto) { 3377 if (!Proto->isVariadic()) { 3378 Diag(Args[NumArgsInProto]->getLocStart(), 3379 diag::err_typecheck_call_too_many_args) 3380 << Fn->getType()->isBlockPointerType() 3381 << NumArgsInProto << NumArgs << Fn->getSourceRange() 3382 << SourceRange(Args[NumArgsInProto]->getLocStart(), 3383 Args[NumArgs-1]->getLocEnd()); 3384 // This deletes the extra arguments. 3385 Call->setNumArgs(Context, NumArgsInProto); 3386 return true; 3387 } 3388 } 3389 llvm::SmallVector<Expr *, 8> AllArgs; 3390 VariadicCallType CallType = 3391 Proto->isVariadic() ? VariadicFunction : VariadicDoesNotApply; 3392 if (Fn->getType()->isBlockPointerType()) 3393 CallType = VariadicBlock; // Block 3394 else if (isa<MemberExpr>(Fn)) 3395 CallType = VariadicMethod; 3396 Invalid = GatherArgumentsForCall(Call->getSourceRange().getBegin(), FDecl, 3397 Proto, 0, Args, NumArgs, AllArgs, CallType); 3398 if (Invalid) 3399 return true; 3400 unsigned TotalNumArgs = AllArgs.size(); 3401 for (unsigned i = 0; i < TotalNumArgs; ++i) 3402 Call->setArg(i, AllArgs[i]); 3403 3404 return false; 3405} 3406 3407bool Sema::GatherArgumentsForCall(SourceLocation CallLoc, 3408 FunctionDecl *FDecl, 3409 const FunctionProtoType *Proto, 3410 unsigned FirstProtoArg, 3411 Expr **Args, unsigned NumArgs, 3412 llvm::SmallVector<Expr *, 8> &AllArgs, 3413 VariadicCallType CallType) { 3414 unsigned NumArgsInProto = Proto->getNumArgs(); 3415 unsigned NumArgsToCheck = NumArgs; 3416 bool Invalid = false; 3417 if (NumArgs != NumArgsInProto) 3418 // Use default arguments for missing arguments 3419 NumArgsToCheck = NumArgsInProto; 3420 unsigned ArgIx = 0; 3421 // Continue to check argument types (even if we have too few/many args). 3422 for (unsigned i = FirstProtoArg; i != NumArgsToCheck; i++) { 3423 QualType ProtoArgType = Proto->getArgType(i); 3424 3425 Expr *Arg; 3426 if (ArgIx < NumArgs) { 3427 Arg = Args[ArgIx++]; 3428 3429 if (RequireCompleteType(Arg->getSourceRange().getBegin(), 3430 ProtoArgType, 3431 PDiag(diag::err_call_incomplete_argument) 3432 << Arg->getSourceRange())) 3433 return true; 3434 3435 // Pass the argument 3436 ParmVarDecl *Param = 0; 3437 if (FDecl && i < FDecl->getNumParams()) 3438 Param = FDecl->getParamDecl(i); 3439 3440 3441 InitializedEntity Entity = 3442 Param? InitializedEntity::InitializeParameter(Param) 3443 : InitializedEntity::InitializeParameter(ProtoArgType); 3444 OwningExprResult ArgE = PerformCopyInitialization(Entity, 3445 SourceLocation(), 3446 Owned(Arg)); 3447 if (ArgE.isInvalid()) 3448 return true; 3449 3450 Arg = ArgE.takeAs<Expr>(); 3451 } else { 3452 ParmVarDecl *Param = FDecl->getParamDecl(i); 3453 3454 OwningExprResult ArgExpr = 3455 BuildCXXDefaultArgExpr(CallLoc, FDecl, Param); 3456 if (ArgExpr.isInvalid()) 3457 return true; 3458 3459 Arg = ArgExpr.takeAs<Expr>(); 3460 } 3461 AllArgs.push_back(Arg); 3462 } 3463 3464 // If this is a variadic call, handle args passed through "...". 3465 if (CallType != VariadicDoesNotApply) { 3466 // Promote the arguments (C99 6.5.2.2p7). 3467 for (unsigned i = ArgIx; i != NumArgs; ++i) { 3468 Expr *Arg = Args[i]; 3469 Invalid |= DefaultVariadicArgumentPromotion(Arg, CallType, FDecl); 3470 AllArgs.push_back(Arg); 3471 } 3472 } 3473 return Invalid; 3474} 3475 3476/// ActOnCallExpr - Handle a call to Fn with the specified array of arguments. 3477/// This provides the location of the left/right parens and a list of comma 3478/// locations. 3479Action::OwningExprResult 3480Sema::ActOnCallExpr(Scope *S, ExprArg fn, SourceLocation LParenLoc, 3481 MultiExprArg args, 3482 SourceLocation *CommaLocs, SourceLocation RParenLoc) { 3483 unsigned NumArgs = args.size(); 3484 3485 // Since this might be a postfix expression, get rid of ParenListExprs. 3486 fn = MaybeConvertParenListExprToParenExpr(S, move(fn)); 3487 3488 Expr *Fn = fn.takeAs<Expr>(); 3489 Expr **Args = reinterpret_cast<Expr**>(args.release()); 3490 assert(Fn && "no function call expression"); 3491 3492 if (getLangOptions().CPlusPlus) { 3493 // If this is a pseudo-destructor expression, build the call immediately. 3494 if (isa<CXXPseudoDestructorExpr>(Fn)) { 3495 if (NumArgs > 0) { 3496 // Pseudo-destructor calls should not have any arguments. 3497 Diag(Fn->getLocStart(), diag::err_pseudo_dtor_call_with_args) 3498 << FixItHint::CreateRemoval( 3499 SourceRange(Args[0]->getLocStart(), 3500 Args[NumArgs-1]->getLocEnd())); 3501 3502 for (unsigned I = 0; I != NumArgs; ++I) 3503 Args[I]->Destroy(Context); 3504 3505 NumArgs = 0; 3506 } 3507 3508 return Owned(new (Context) CallExpr(Context, Fn, 0, 0, Context.VoidTy, 3509 RParenLoc)); 3510 } 3511 3512 // Determine whether this is a dependent call inside a C++ template, 3513 // in which case we won't do any semantic analysis now. 3514 // FIXME: Will need to cache the results of name lookup (including ADL) in 3515 // Fn. 3516 bool Dependent = false; 3517 if (Fn->isTypeDependent()) 3518 Dependent = true; 3519 else if (Expr::hasAnyTypeDependentArguments(Args, NumArgs)) 3520 Dependent = true; 3521 3522 if (Dependent) 3523 return Owned(new (Context) CallExpr(Context, Fn, Args, NumArgs, 3524 Context.DependentTy, RParenLoc)); 3525 3526 // Determine whether this is a call to an object (C++ [over.call.object]). 3527 if (Fn->getType()->isRecordType()) 3528 return Owned(BuildCallToObjectOfClassType(S, Fn, LParenLoc, Args, NumArgs, 3529 CommaLocs, RParenLoc)); 3530 3531 Expr *NakedFn = Fn->IgnoreParens(); 3532 3533 // Determine whether this is a call to an unresolved member function. 3534 if (UnresolvedMemberExpr *MemE = dyn_cast<UnresolvedMemberExpr>(NakedFn)) { 3535 // If lookup was unresolved but not dependent (i.e. didn't find 3536 // an unresolved using declaration), it has to be an overloaded 3537 // function set, which means it must contain either multiple 3538 // declarations (all methods or method templates) or a single 3539 // method template. 3540 assert((MemE->getNumDecls() > 1) || 3541 isa<FunctionTemplateDecl>( 3542 (*MemE->decls_begin())->getUnderlyingDecl())); 3543 (void)MemE; 3544 3545 return BuildCallToMemberFunction(S, Fn, LParenLoc, Args, NumArgs, 3546 CommaLocs, RParenLoc); 3547 } 3548 3549 // Determine whether this is a call to a member function. 3550 if (MemberExpr *MemExpr = dyn_cast<MemberExpr>(NakedFn)) { 3551 NamedDecl *MemDecl = MemExpr->getMemberDecl(); 3552 if (isa<CXXMethodDecl>(MemDecl)) 3553 return BuildCallToMemberFunction(S, Fn, LParenLoc, Args, NumArgs, 3554 CommaLocs, RParenLoc); 3555 } 3556 3557 // Determine whether this is a call to a pointer-to-member function. 3558 if (BinaryOperator *BO = dyn_cast<BinaryOperator>(NakedFn)) { 3559 if (BO->getOpcode() == BinaryOperator::PtrMemD || 3560 BO->getOpcode() == BinaryOperator::PtrMemI) { 3561 if (const FunctionProtoType *FPT 3562 = BO->getType()->getAs<FunctionProtoType>()) { 3563 QualType ResultTy = FPT->getResultType().getNonReferenceType(); 3564 3565 ExprOwningPtr<CXXMemberCallExpr> 3566 TheCall(this, new (Context) CXXMemberCallExpr(Context, BO, Args, 3567 NumArgs, ResultTy, 3568 RParenLoc)); 3569 3570 if (CheckCallReturnType(FPT->getResultType(), 3571 BO->getRHS()->getSourceRange().getBegin(), 3572 TheCall.get(), 0)) 3573 return ExprError(); 3574 3575 if (ConvertArgumentsForCall(&*TheCall, BO, 0, FPT, Args, NumArgs, 3576 RParenLoc)) 3577 return ExprError(); 3578 3579 return Owned(MaybeBindToTemporary(TheCall.release()).release()); 3580 } 3581 return ExprError(Diag(Fn->getLocStart(), 3582 diag::err_typecheck_call_not_function) 3583 << Fn->getType() << Fn->getSourceRange()); 3584 } 3585 } 3586 } 3587 3588 // If we're directly calling a function, get the appropriate declaration. 3589 // Also, in C++, keep track of whether we should perform argument-dependent 3590 // lookup and whether there were any explicitly-specified template arguments. 3591 3592 Expr *NakedFn = Fn->IgnoreParens(); 3593 if (isa<UnresolvedLookupExpr>(NakedFn)) { 3594 UnresolvedLookupExpr *ULE = cast<UnresolvedLookupExpr>(NakedFn); 3595 return BuildOverloadedCallExpr(S, Fn, ULE, LParenLoc, Args, NumArgs, 3596 CommaLocs, RParenLoc); 3597 } 3598 3599 NamedDecl *NDecl = 0; 3600 if (isa<DeclRefExpr>(NakedFn)) 3601 NDecl = cast<DeclRefExpr>(NakedFn)->getDecl(); 3602 3603 return BuildResolvedCallExpr(Fn, NDecl, LParenLoc, Args, NumArgs, RParenLoc); 3604} 3605 3606/// BuildResolvedCallExpr - Build a call to a resolved expression, 3607/// i.e. an expression not of \p OverloadTy. The expression should 3608/// unary-convert to an expression of function-pointer or 3609/// block-pointer type. 3610/// 3611/// \param NDecl the declaration being called, if available 3612Sema::OwningExprResult 3613Sema::BuildResolvedCallExpr(Expr *Fn, NamedDecl *NDecl, 3614 SourceLocation LParenLoc, 3615 Expr **Args, unsigned NumArgs, 3616 SourceLocation RParenLoc) { 3617 FunctionDecl *FDecl = dyn_cast_or_null<FunctionDecl>(NDecl); 3618 3619 // Promote the function operand. 3620 UsualUnaryConversions(Fn); 3621 3622 // Make the call expr early, before semantic checks. This guarantees cleanup 3623 // of arguments and function on error. 3624 ExprOwningPtr<CallExpr> TheCall(this, new (Context) CallExpr(Context, Fn, 3625 Args, NumArgs, 3626 Context.BoolTy, 3627 RParenLoc)); 3628 3629 const FunctionType *FuncT; 3630 if (!Fn->getType()->isBlockPointerType()) { 3631 // C99 6.5.2.2p1 - "The expression that denotes the called function shall 3632 // have type pointer to function". 3633 const PointerType *PT = Fn->getType()->getAs<PointerType>(); 3634 if (PT == 0) 3635 return ExprError(Diag(LParenLoc, diag::err_typecheck_call_not_function) 3636 << Fn->getType() << Fn->getSourceRange()); 3637 FuncT = PT->getPointeeType()->getAs<FunctionType>(); 3638 } else { // This is a block call. 3639 FuncT = Fn->getType()->getAs<BlockPointerType>()->getPointeeType()-> 3640 getAs<FunctionType>(); 3641 } 3642 if (FuncT == 0) 3643 return ExprError(Diag(LParenLoc, diag::err_typecheck_call_not_function) 3644 << Fn->getType() << Fn->getSourceRange()); 3645 3646 // Check for a valid return type 3647 if (CheckCallReturnType(FuncT->getResultType(), 3648 Fn->getSourceRange().getBegin(), TheCall.get(), 3649 FDecl)) 3650 return ExprError(); 3651 3652 // We know the result type of the call, set it. 3653 TheCall->setType(FuncT->getResultType().getNonReferenceType()); 3654 3655 if (const FunctionProtoType *Proto = dyn_cast<FunctionProtoType>(FuncT)) { 3656 if (ConvertArgumentsForCall(&*TheCall, Fn, FDecl, Proto, Args, NumArgs, 3657 RParenLoc)) 3658 return ExprError(); 3659 } else { 3660 assert(isa<FunctionNoProtoType>(FuncT) && "Unknown FunctionType!"); 3661 3662 if (FDecl) { 3663 // Check if we have too few/too many template arguments, based 3664 // on our knowledge of the function definition. 3665 const FunctionDecl *Def = 0; 3666 if (FDecl->getBody(Def) && NumArgs != Def->param_size()) { 3667 const FunctionProtoType *Proto = 3668 Def->getType()->getAs<FunctionProtoType>(); 3669 if (!Proto || !(Proto->isVariadic() && NumArgs >= Def->param_size())) { 3670 Diag(RParenLoc, diag::warn_call_wrong_number_of_arguments) 3671 << (NumArgs > Def->param_size()) << FDecl << Fn->getSourceRange(); 3672 } 3673 } 3674 } 3675 3676 // Promote the arguments (C99 6.5.2.2p6). 3677 for (unsigned i = 0; i != NumArgs; i++) { 3678 Expr *Arg = Args[i]; 3679 DefaultArgumentPromotion(Arg); 3680 if (RequireCompleteType(Arg->getSourceRange().getBegin(), 3681 Arg->getType(), 3682 PDiag(diag::err_call_incomplete_argument) 3683 << Arg->getSourceRange())) 3684 return ExprError(); 3685 TheCall->setArg(i, Arg); 3686 } 3687 } 3688 3689 if (CXXMethodDecl *Method = dyn_cast_or_null<CXXMethodDecl>(FDecl)) 3690 if (!Method->isStatic()) 3691 return ExprError(Diag(LParenLoc, diag::err_member_call_without_object) 3692 << Fn->getSourceRange()); 3693 3694 // Check for sentinels 3695 if (NDecl) 3696 DiagnoseSentinelCalls(NDecl, LParenLoc, Args, NumArgs); 3697 3698 // Do special checking on direct calls to functions. 3699 if (FDecl) { 3700 if (CheckFunctionCall(FDecl, TheCall.get())) 3701 return ExprError(); 3702 3703 if (unsigned BuiltinID = FDecl->getBuiltinID()) 3704 return CheckBuiltinFunctionCall(BuiltinID, TheCall.take()); 3705 } else if (NDecl) { 3706 if (CheckBlockCall(NDecl, TheCall.get())) 3707 return ExprError(); 3708 } 3709 3710 return MaybeBindToTemporary(TheCall.take()); 3711} 3712 3713Action::OwningExprResult 3714Sema::ActOnCompoundLiteral(SourceLocation LParenLoc, TypeTy *Ty, 3715 SourceLocation RParenLoc, ExprArg InitExpr) { 3716 assert((Ty != 0) && "ActOnCompoundLiteral(): missing type"); 3717 // FIXME: put back this assert when initializers are worked out. 3718 //assert((InitExpr != 0) && "ActOnCompoundLiteral(): missing expression"); 3719 3720 TypeSourceInfo *TInfo; 3721 QualType literalType = GetTypeFromParser(Ty, &TInfo); 3722 if (!TInfo) 3723 TInfo = Context.getTrivialTypeSourceInfo(literalType); 3724 3725 return BuildCompoundLiteralExpr(LParenLoc, TInfo, RParenLoc, move(InitExpr)); 3726} 3727 3728Action::OwningExprResult 3729Sema::BuildCompoundLiteralExpr(SourceLocation LParenLoc, TypeSourceInfo *TInfo, 3730 SourceLocation RParenLoc, ExprArg InitExpr) { 3731 QualType literalType = TInfo->getType(); 3732 Expr *literalExpr = static_cast<Expr*>(InitExpr.get()); 3733 3734 if (literalType->isArrayType()) { 3735 if (literalType->isVariableArrayType()) 3736 return ExprError(Diag(LParenLoc, diag::err_variable_object_no_init) 3737 << SourceRange(LParenLoc, literalExpr->getSourceRange().getEnd())); 3738 } else if (!literalType->isDependentType() && 3739 RequireCompleteType(LParenLoc, literalType, 3740 PDiag(diag::err_typecheck_decl_incomplete_type) 3741 << SourceRange(LParenLoc, 3742 literalExpr->getSourceRange().getEnd()))) 3743 return ExprError(); 3744 3745 InitializedEntity Entity 3746 = InitializedEntity::InitializeTemporary(literalType); 3747 InitializationKind Kind 3748 = InitializationKind::CreateCast(SourceRange(LParenLoc, RParenLoc), 3749 /*IsCStyleCast=*/true); 3750 InitializationSequence InitSeq(*this, Entity, Kind, &literalExpr, 1); 3751 OwningExprResult Result = InitSeq.Perform(*this, Entity, Kind, 3752 MultiExprArg(*this, (void**)&literalExpr, 1), 3753 &literalType); 3754 if (Result.isInvalid()) 3755 return ExprError(); 3756 InitExpr.release(); 3757 literalExpr = static_cast<Expr*>(Result.get()); 3758 3759 bool isFileScope = getCurFunctionOrMethodDecl() == 0; 3760 if (isFileScope) { // 6.5.2.5p3 3761 if (CheckForConstantInitializer(literalExpr, literalType)) 3762 return ExprError(); 3763 } 3764 3765 Result.release(); 3766 3767 return Owned(new (Context) CompoundLiteralExpr(LParenLoc, TInfo, literalType, 3768 literalExpr, isFileScope)); 3769} 3770 3771Action::OwningExprResult 3772Sema::ActOnInitList(SourceLocation LBraceLoc, MultiExprArg initlist, 3773 SourceLocation RBraceLoc) { 3774 unsigned NumInit = initlist.size(); 3775 Expr **InitList = reinterpret_cast<Expr**>(initlist.release()); 3776 3777 // Semantic analysis for initializers is done by ActOnDeclarator() and 3778 // CheckInitializer() - it requires knowledge of the object being intialized. 3779 3780 InitListExpr *E = new (Context) InitListExpr(Context, LBraceLoc, InitList, 3781 NumInit, RBraceLoc); 3782 E->setType(Context.VoidTy); // FIXME: just a place holder for now. 3783 return Owned(E); 3784} 3785 3786static CastExpr::CastKind getScalarCastKind(ASTContext &Context, 3787 QualType SrcTy, QualType DestTy) { 3788 if (Context.hasSameUnqualifiedType(SrcTy, DestTy)) 3789 return CastExpr::CK_NoOp; 3790 3791 if (SrcTy->hasPointerRepresentation()) { 3792 if (DestTy->hasPointerRepresentation()) 3793 return DestTy->isObjCObjectPointerType() ? 3794 CastExpr::CK_AnyPointerToObjCPointerCast : 3795 CastExpr::CK_BitCast; 3796 if (DestTy->isIntegerType()) 3797 return CastExpr::CK_PointerToIntegral; 3798 } 3799 3800 if (SrcTy->isIntegerType()) { 3801 if (DestTy->isIntegerType()) 3802 return CastExpr::CK_IntegralCast; 3803 if (DestTy->hasPointerRepresentation()) 3804 return CastExpr::CK_IntegralToPointer; 3805 if (DestTy->isRealFloatingType()) 3806 return CastExpr::CK_IntegralToFloating; 3807 } 3808 3809 if (SrcTy->isRealFloatingType()) { 3810 if (DestTy->isRealFloatingType()) 3811 return CastExpr::CK_FloatingCast; 3812 if (DestTy->isIntegerType()) 3813 return CastExpr::CK_FloatingToIntegral; 3814 } 3815 3816 // FIXME: Assert here. 3817 // assert(false && "Unhandled cast combination!"); 3818 return CastExpr::CK_Unknown; 3819} 3820 3821/// CheckCastTypes - Check type constraints for casting between types. 3822bool Sema::CheckCastTypes(SourceRange TyR, QualType castType, Expr *&castExpr, 3823 CastExpr::CastKind& Kind, 3824 CXXBaseSpecifierArray &BasePath, 3825 bool FunctionalStyle) { 3826 if (getLangOptions().CPlusPlus) 3827 return CXXCheckCStyleCast(TyR, castType, castExpr, Kind, BasePath, 3828 FunctionalStyle); 3829 3830 DefaultFunctionArrayLvalueConversion(castExpr); 3831 3832 // C99 6.5.4p2: the cast type needs to be void or scalar and the expression 3833 // type needs to be scalar. 3834 if (castType->isVoidType()) { 3835 // Cast to void allows any expr type. 3836 Kind = CastExpr::CK_ToVoid; 3837 return false; 3838 } 3839 3840 if (!castType->isScalarType() && !castType->isVectorType()) { 3841 if (Context.hasSameUnqualifiedType(castType, castExpr->getType()) && 3842 (castType->isStructureType() || castType->isUnionType())) { 3843 // GCC struct/union extension: allow cast to self. 3844 // FIXME: Check that the cast destination type is complete. 3845 Diag(TyR.getBegin(), diag::ext_typecheck_cast_nonscalar) 3846 << castType << castExpr->getSourceRange(); 3847 Kind = CastExpr::CK_NoOp; 3848 return false; 3849 } 3850 3851 if (castType->isUnionType()) { 3852 // GCC cast to union extension 3853 RecordDecl *RD = castType->getAs<RecordType>()->getDecl(); 3854 RecordDecl::field_iterator Field, FieldEnd; 3855 for (Field = RD->field_begin(), FieldEnd = RD->field_end(); 3856 Field != FieldEnd; ++Field) { 3857 if (Context.hasSameUnqualifiedType(Field->getType(), 3858 castExpr->getType())) { 3859 Diag(TyR.getBegin(), diag::ext_typecheck_cast_to_union) 3860 << castExpr->getSourceRange(); 3861 break; 3862 } 3863 } 3864 if (Field == FieldEnd) 3865 return Diag(TyR.getBegin(), diag::err_typecheck_cast_to_union_no_type) 3866 << castExpr->getType() << castExpr->getSourceRange(); 3867 Kind = CastExpr::CK_ToUnion; 3868 return false; 3869 } 3870 3871 // Reject any other conversions to non-scalar types. 3872 return Diag(TyR.getBegin(), diag::err_typecheck_cond_expect_scalar) 3873 << castType << castExpr->getSourceRange(); 3874 } 3875 3876 if (!castExpr->getType()->isScalarType() && 3877 !castExpr->getType()->isVectorType()) { 3878 return Diag(castExpr->getLocStart(), 3879 diag::err_typecheck_expect_scalar_operand) 3880 << castExpr->getType() << castExpr->getSourceRange(); 3881 } 3882 3883 if (castType->isExtVectorType()) 3884 return CheckExtVectorCast(TyR, castType, castExpr, Kind); 3885 3886 if (castType->isVectorType()) 3887 return CheckVectorCast(TyR, castType, castExpr->getType(), Kind); 3888 if (castExpr->getType()->isVectorType()) 3889 return CheckVectorCast(TyR, castExpr->getType(), castType, Kind); 3890 3891 if (isa<ObjCSelectorExpr>(castExpr)) 3892 return Diag(castExpr->getLocStart(), diag::err_cast_selector_expr); 3893 3894 if (!castType->isArithmeticType()) { 3895 QualType castExprType = castExpr->getType(); 3896 if (!castExprType->isIntegralType() && castExprType->isArithmeticType()) 3897 return Diag(castExpr->getLocStart(), 3898 diag::err_cast_pointer_from_non_pointer_int) 3899 << castExprType << castExpr->getSourceRange(); 3900 } else if (!castExpr->getType()->isArithmeticType()) { 3901 if (!castType->isIntegralType() && castType->isArithmeticType()) 3902 return Diag(castExpr->getLocStart(), 3903 diag::err_cast_pointer_to_non_pointer_int) 3904 << castType << castExpr->getSourceRange(); 3905 } 3906 3907 Kind = getScalarCastKind(Context, castExpr->getType(), castType); 3908 return false; 3909} 3910 3911bool Sema::CheckVectorCast(SourceRange R, QualType VectorTy, QualType Ty, 3912 CastExpr::CastKind &Kind) { 3913 assert(VectorTy->isVectorType() && "Not a vector type!"); 3914 3915 if (Ty->isVectorType() || Ty->isIntegerType()) { 3916 if (Context.getTypeSize(VectorTy) != Context.getTypeSize(Ty)) 3917 return Diag(R.getBegin(), 3918 Ty->isVectorType() ? 3919 diag::err_invalid_conversion_between_vectors : 3920 diag::err_invalid_conversion_between_vector_and_integer) 3921 << VectorTy << Ty << R; 3922 } else 3923 return Diag(R.getBegin(), 3924 diag::err_invalid_conversion_between_vector_and_scalar) 3925 << VectorTy << Ty << R; 3926 3927 Kind = CastExpr::CK_BitCast; 3928 return false; 3929} 3930 3931bool Sema::CheckExtVectorCast(SourceRange R, QualType DestTy, Expr *&CastExpr, 3932 CastExpr::CastKind &Kind) { 3933 assert(DestTy->isExtVectorType() && "Not an extended vector type!"); 3934 3935 QualType SrcTy = CastExpr->getType(); 3936 3937 // If SrcTy is a VectorType, the total size must match to explicitly cast to 3938 // an ExtVectorType. 3939 if (SrcTy->isVectorType()) { 3940 if (Context.getTypeSize(DestTy) != Context.getTypeSize(SrcTy)) 3941 return Diag(R.getBegin(),diag::err_invalid_conversion_between_ext_vectors) 3942 << DestTy << SrcTy << R; 3943 Kind = CastExpr::CK_BitCast; 3944 return false; 3945 } 3946 3947 // All non-pointer scalars can be cast to ExtVector type. The appropriate 3948 // conversion will take place first from scalar to elt type, and then 3949 // splat from elt type to vector. 3950 if (SrcTy->isPointerType()) 3951 return Diag(R.getBegin(), 3952 diag::err_invalid_conversion_between_vector_and_scalar) 3953 << DestTy << SrcTy << R; 3954 3955 QualType DestElemTy = DestTy->getAs<ExtVectorType>()->getElementType(); 3956 ImpCastExprToType(CastExpr, DestElemTy, 3957 getScalarCastKind(Context, SrcTy, DestElemTy)); 3958 3959 Kind = CastExpr::CK_VectorSplat; 3960 return false; 3961} 3962 3963Action::OwningExprResult 3964Sema::ActOnCastExpr(Scope *S, SourceLocation LParenLoc, TypeTy *Ty, 3965 SourceLocation RParenLoc, ExprArg Op) { 3966 assert((Ty != 0) && (Op.get() != 0) && 3967 "ActOnCastExpr(): missing type or expr"); 3968 3969 TypeSourceInfo *castTInfo; 3970 QualType castType = GetTypeFromParser(Ty, &castTInfo); 3971 if (!castTInfo) 3972 castTInfo = Context.getTrivialTypeSourceInfo(castType); 3973 3974 // If the Expr being casted is a ParenListExpr, handle it specially. 3975 Expr *castExpr = (Expr *)Op.get(); 3976 if (isa<ParenListExpr>(castExpr)) 3977 return ActOnCastOfParenListExpr(S, LParenLoc, RParenLoc, move(Op), 3978 castTInfo); 3979 3980 return BuildCStyleCastExpr(LParenLoc, castTInfo, RParenLoc, move(Op)); 3981} 3982 3983Action::OwningExprResult 3984Sema::BuildCStyleCastExpr(SourceLocation LParenLoc, TypeSourceInfo *Ty, 3985 SourceLocation RParenLoc, ExprArg Op) { 3986 Expr *castExpr = static_cast<Expr*>(Op.get()); 3987 3988 CastExpr::CastKind Kind = CastExpr::CK_Unknown; 3989 CXXBaseSpecifierArray BasePath; 3990 if (CheckCastTypes(SourceRange(LParenLoc, RParenLoc), Ty->getType(), castExpr, 3991 Kind, BasePath)) 3992 return ExprError(); 3993 3994 Op.release(); 3995 return Owned(new (Context) CStyleCastExpr(Ty->getType().getNonReferenceType(), 3996 Kind, castExpr, BasePath, Ty, 3997 LParenLoc, RParenLoc)); 3998} 3999 4000/// This is not an AltiVec-style cast, so turn the ParenListExpr into a sequence 4001/// of comma binary operators. 4002Action::OwningExprResult 4003Sema::MaybeConvertParenListExprToParenExpr(Scope *S, ExprArg EA) { 4004 Expr *expr = EA.takeAs<Expr>(); 4005 ParenListExpr *E = dyn_cast<ParenListExpr>(expr); 4006 if (!E) 4007 return Owned(expr); 4008 4009 OwningExprResult Result(*this, E->getExpr(0)); 4010 4011 for (unsigned i = 1, e = E->getNumExprs(); i != e && !Result.isInvalid(); ++i) 4012 Result = ActOnBinOp(S, E->getExprLoc(), tok::comma, move(Result), 4013 Owned(E->getExpr(i))); 4014 4015 return ActOnParenExpr(E->getLParenLoc(), E->getRParenLoc(), move(Result)); 4016} 4017 4018Action::OwningExprResult 4019Sema::ActOnCastOfParenListExpr(Scope *S, SourceLocation LParenLoc, 4020 SourceLocation RParenLoc, ExprArg Op, 4021 TypeSourceInfo *TInfo) { 4022 ParenListExpr *PE = (ParenListExpr *)Op.get(); 4023 QualType Ty = TInfo->getType(); 4024 4025 // If this is an altivec initializer, '(' type ')' '(' init, ..., init ')' 4026 // then handle it as such. 4027 if (getLangOptions().AltiVec && Ty->isVectorType()) { 4028 if (PE->getNumExprs() == 0) { 4029 Diag(PE->getExprLoc(), diag::err_altivec_empty_initializer); 4030 return ExprError(); 4031 } 4032 4033 llvm::SmallVector<Expr *, 8> initExprs; 4034 for (unsigned i = 0, e = PE->getNumExprs(); i != e; ++i) 4035 initExprs.push_back(PE->getExpr(i)); 4036 4037 // FIXME: This means that pretty-printing the final AST will produce curly 4038 // braces instead of the original commas. 4039 Op.release(); 4040 InitListExpr *E = new (Context) InitListExpr(Context, LParenLoc, 4041 &initExprs[0], 4042 initExprs.size(), RParenLoc); 4043 E->setType(Ty); 4044 return BuildCompoundLiteralExpr(LParenLoc, TInfo, RParenLoc, Owned(E)); 4045 } else { 4046 // This is not an AltiVec-style cast, so turn the ParenListExpr into a 4047 // sequence of BinOp comma operators. 4048 Op = MaybeConvertParenListExprToParenExpr(S, move(Op)); 4049 return BuildCStyleCastExpr(LParenLoc, TInfo, RParenLoc, move(Op)); 4050 } 4051} 4052 4053Action::OwningExprResult Sema::ActOnParenOrParenListExpr(SourceLocation L, 4054 SourceLocation R, 4055 MultiExprArg Val, 4056 TypeTy *TypeOfCast) { 4057 unsigned nexprs = Val.size(); 4058 Expr **exprs = reinterpret_cast<Expr**>(Val.release()); 4059 assert((exprs != 0) && "ActOnParenOrParenListExpr() missing expr list"); 4060 Expr *expr; 4061 if (nexprs == 1 && TypeOfCast && !TypeIsVectorType(TypeOfCast)) 4062 expr = new (Context) ParenExpr(L, R, exprs[0]); 4063 else 4064 expr = new (Context) ParenListExpr(Context, L, exprs, nexprs, R); 4065 return Owned(expr); 4066} 4067 4068/// Note that lhs is not null here, even if this is the gnu "x ?: y" extension. 4069/// In that case, lhs = cond. 4070/// C99 6.5.15 4071QualType Sema::CheckConditionalOperands(Expr *&Cond, Expr *&LHS, Expr *&RHS, 4072 SourceLocation QuestionLoc) { 4073 // C++ is sufficiently different to merit its own checker. 4074 if (getLangOptions().CPlusPlus) 4075 return CXXCheckConditionalOperands(Cond, LHS, RHS, QuestionLoc); 4076 4077 UsualUnaryConversions(Cond); 4078 UsualUnaryConversions(LHS); 4079 UsualUnaryConversions(RHS); 4080 QualType CondTy = Cond->getType(); 4081 QualType LHSTy = LHS->getType(); 4082 QualType RHSTy = RHS->getType(); 4083 4084 // first, check the condition. 4085 if (!CondTy->isScalarType()) { // C99 6.5.15p2 4086 Diag(Cond->getLocStart(), diag::err_typecheck_cond_expect_scalar) 4087 << CondTy; 4088 return QualType(); 4089 } 4090 4091 // Now check the two expressions. 4092 if (LHSTy->isVectorType() || RHSTy->isVectorType()) 4093 return CheckVectorOperands(QuestionLoc, LHS, RHS); 4094 4095 // If both operands have arithmetic type, do the usual arithmetic conversions 4096 // to find a common type: C99 6.5.15p3,5. 4097 if (LHSTy->isArithmeticType() && RHSTy->isArithmeticType()) { 4098 UsualArithmeticConversions(LHS, RHS); 4099 return LHS->getType(); 4100 } 4101 4102 // If both operands are the same structure or union type, the result is that 4103 // type. 4104 if (const RecordType *LHSRT = LHSTy->getAs<RecordType>()) { // C99 6.5.15p3 4105 if (const RecordType *RHSRT = RHSTy->getAs<RecordType>()) 4106 if (LHSRT->getDecl() == RHSRT->getDecl()) 4107 // "If both the operands have structure or union type, the result has 4108 // that type." This implies that CV qualifiers are dropped. 4109 return LHSTy.getUnqualifiedType(); 4110 // FIXME: Type of conditional expression must be complete in C mode. 4111 } 4112 4113 // C99 6.5.15p5: "If both operands have void type, the result has void type." 4114 // The following || allows only one side to be void (a GCC-ism). 4115 if (LHSTy->isVoidType() || RHSTy->isVoidType()) { 4116 if (!LHSTy->isVoidType()) 4117 Diag(RHS->getLocStart(), diag::ext_typecheck_cond_one_void) 4118 << RHS->getSourceRange(); 4119 if (!RHSTy->isVoidType()) 4120 Diag(LHS->getLocStart(), diag::ext_typecheck_cond_one_void) 4121 << LHS->getSourceRange(); 4122 ImpCastExprToType(LHS, Context.VoidTy, CastExpr::CK_ToVoid); 4123 ImpCastExprToType(RHS, Context.VoidTy, CastExpr::CK_ToVoid); 4124 return Context.VoidTy; 4125 } 4126 // C99 6.5.15p6 - "if one operand is a null pointer constant, the result has 4127 // the type of the other operand." 4128 if ((LHSTy->isAnyPointerType() || LHSTy->isBlockPointerType()) && 4129 RHS->isNullPointerConstant(Context, Expr::NPC_ValueDependentIsNull)) { 4130 // promote the null to a pointer. 4131 ImpCastExprToType(RHS, LHSTy, CastExpr::CK_Unknown); 4132 return LHSTy; 4133 } 4134 if ((RHSTy->isAnyPointerType() || RHSTy->isBlockPointerType()) && 4135 LHS->isNullPointerConstant(Context, Expr::NPC_ValueDependentIsNull)) { 4136 ImpCastExprToType(LHS, RHSTy, CastExpr::CK_Unknown); 4137 return RHSTy; 4138 } 4139 4140 // All objective-c pointer type analysis is done here. 4141 QualType compositeType = FindCompositeObjCPointerType(LHS, RHS, 4142 QuestionLoc); 4143 if (!compositeType.isNull()) 4144 return compositeType; 4145 4146 4147 // Handle block pointer types. 4148 if (LHSTy->isBlockPointerType() || RHSTy->isBlockPointerType()) { 4149 if (!LHSTy->isBlockPointerType() || !RHSTy->isBlockPointerType()) { 4150 if (LHSTy->isVoidPointerType() || RHSTy->isVoidPointerType()) { 4151 QualType destType = Context.getPointerType(Context.VoidTy); 4152 ImpCastExprToType(LHS, destType, CastExpr::CK_BitCast); 4153 ImpCastExprToType(RHS, destType, CastExpr::CK_BitCast); 4154 return destType; 4155 } 4156 Diag(QuestionLoc, diag::err_typecheck_cond_incompatible_operands) 4157 << LHSTy << RHSTy << LHS->getSourceRange() << RHS->getSourceRange(); 4158 return QualType(); 4159 } 4160 // We have 2 block pointer types. 4161 if (Context.getCanonicalType(LHSTy) == Context.getCanonicalType(RHSTy)) { 4162 // Two identical block pointer types are always compatible. 4163 return LHSTy; 4164 } 4165 // The block pointer types aren't identical, continue checking. 4166 QualType lhptee = LHSTy->getAs<BlockPointerType>()->getPointeeType(); 4167 QualType rhptee = RHSTy->getAs<BlockPointerType>()->getPointeeType(); 4168 4169 if (!Context.typesAreCompatible(lhptee.getUnqualifiedType(), 4170 rhptee.getUnqualifiedType())) { 4171 Diag(QuestionLoc, diag::warn_typecheck_cond_incompatible_pointers) 4172 << LHSTy << RHSTy << LHS->getSourceRange() << RHS->getSourceRange(); 4173 // In this situation, we assume void* type. No especially good 4174 // reason, but this is what gcc does, and we do have to pick 4175 // to get a consistent AST. 4176 QualType incompatTy = Context.getPointerType(Context.VoidTy); 4177 ImpCastExprToType(LHS, incompatTy, CastExpr::CK_BitCast); 4178 ImpCastExprToType(RHS, incompatTy, CastExpr::CK_BitCast); 4179 return incompatTy; 4180 } 4181 // The block pointer types are compatible. 4182 ImpCastExprToType(LHS, LHSTy, CastExpr::CK_BitCast); 4183 ImpCastExprToType(RHS, LHSTy, CastExpr::CK_BitCast); 4184 return LHSTy; 4185 } 4186 4187 // Check constraints for C object pointers types (C99 6.5.15p3,6). 4188 if (LHSTy->isPointerType() && RHSTy->isPointerType()) { 4189 // get the "pointed to" types 4190 QualType lhptee = LHSTy->getAs<PointerType>()->getPointeeType(); 4191 QualType rhptee = RHSTy->getAs<PointerType>()->getPointeeType(); 4192 4193 // ignore qualifiers on void (C99 6.5.15p3, clause 6) 4194 if (lhptee->isVoidType() && rhptee->isIncompleteOrObjectType()) { 4195 // Figure out necessary qualifiers (C99 6.5.15p6) 4196 QualType destPointee 4197 = Context.getQualifiedType(lhptee, rhptee.getQualifiers()); 4198 QualType destType = Context.getPointerType(destPointee); 4199 // Add qualifiers if necessary. 4200 ImpCastExprToType(LHS, destType, CastExpr::CK_NoOp); 4201 // Promote to void*. 4202 ImpCastExprToType(RHS, destType, CastExpr::CK_BitCast); 4203 return destType; 4204 } 4205 if (rhptee->isVoidType() && lhptee->isIncompleteOrObjectType()) { 4206 QualType destPointee 4207 = Context.getQualifiedType(rhptee, lhptee.getQualifiers()); 4208 QualType destType = Context.getPointerType(destPointee); 4209 // Add qualifiers if necessary. 4210 ImpCastExprToType(RHS, destType, CastExpr::CK_NoOp); 4211 // Promote to void*. 4212 ImpCastExprToType(LHS, destType, CastExpr::CK_BitCast); 4213 return destType; 4214 } 4215 4216 if (Context.getCanonicalType(LHSTy) == Context.getCanonicalType(RHSTy)) { 4217 // Two identical pointer types are always compatible. 4218 return LHSTy; 4219 } 4220 if (!Context.typesAreCompatible(lhptee.getUnqualifiedType(), 4221 rhptee.getUnqualifiedType())) { 4222 Diag(QuestionLoc, diag::warn_typecheck_cond_incompatible_pointers) 4223 << LHSTy << RHSTy << LHS->getSourceRange() << RHS->getSourceRange(); 4224 // In this situation, we assume void* type. No especially good 4225 // reason, but this is what gcc does, and we do have to pick 4226 // to get a consistent AST. 4227 QualType incompatTy = Context.getPointerType(Context.VoidTy); 4228 ImpCastExprToType(LHS, incompatTy, CastExpr::CK_BitCast); 4229 ImpCastExprToType(RHS, incompatTy, CastExpr::CK_BitCast); 4230 return incompatTy; 4231 } 4232 // The pointer types are compatible. 4233 // C99 6.5.15p6: If both operands are pointers to compatible types *or* to 4234 // differently qualified versions of compatible types, the result type is 4235 // a pointer to an appropriately qualified version of the *composite* 4236 // type. 4237 // FIXME: Need to calculate the composite type. 4238 // FIXME: Need to add qualifiers 4239 ImpCastExprToType(LHS, LHSTy, CastExpr::CK_BitCast); 4240 ImpCastExprToType(RHS, LHSTy, CastExpr::CK_BitCast); 4241 return LHSTy; 4242 } 4243 4244 // GCC compatibility: soften pointer/integer mismatch. 4245 if (RHSTy->isPointerType() && LHSTy->isIntegerType()) { 4246 Diag(QuestionLoc, diag::warn_typecheck_cond_pointer_integer_mismatch) 4247 << LHSTy << RHSTy << LHS->getSourceRange() << RHS->getSourceRange(); 4248 ImpCastExprToType(LHS, RHSTy, CastExpr::CK_IntegralToPointer); 4249 return RHSTy; 4250 } 4251 if (LHSTy->isPointerType() && RHSTy->isIntegerType()) { 4252 Diag(QuestionLoc, diag::warn_typecheck_cond_pointer_integer_mismatch) 4253 << LHSTy << RHSTy << LHS->getSourceRange() << RHS->getSourceRange(); 4254 ImpCastExprToType(RHS, LHSTy, CastExpr::CK_IntegralToPointer); 4255 return LHSTy; 4256 } 4257 4258 // Otherwise, the operands are not compatible. 4259 Diag(QuestionLoc, diag::err_typecheck_cond_incompatible_operands) 4260 << LHSTy << RHSTy << LHS->getSourceRange() << RHS->getSourceRange(); 4261 return QualType(); 4262} 4263 4264/// FindCompositeObjCPointerType - Helper method to find composite type of 4265/// two objective-c pointer types of the two input expressions. 4266QualType Sema::FindCompositeObjCPointerType(Expr *&LHS, Expr *&RHS, 4267 SourceLocation QuestionLoc) { 4268 QualType LHSTy = LHS->getType(); 4269 QualType RHSTy = RHS->getType(); 4270 4271 // Handle things like Class and struct objc_class*. Here we case the result 4272 // to the pseudo-builtin, because that will be implicitly cast back to the 4273 // redefinition type if an attempt is made to access its fields. 4274 if (LHSTy->isObjCClassType() && 4275 (RHSTy.getDesugaredType() == Context.ObjCClassRedefinitionType)) { 4276 ImpCastExprToType(RHS, LHSTy, CastExpr::CK_BitCast); 4277 return LHSTy; 4278 } 4279 if (RHSTy->isObjCClassType() && 4280 (LHSTy.getDesugaredType() == Context.ObjCClassRedefinitionType)) { 4281 ImpCastExprToType(LHS, RHSTy, CastExpr::CK_BitCast); 4282 return RHSTy; 4283 } 4284 // And the same for struct objc_object* / id 4285 if (LHSTy->isObjCIdType() && 4286 (RHSTy.getDesugaredType() == Context.ObjCIdRedefinitionType)) { 4287 ImpCastExprToType(RHS, LHSTy, CastExpr::CK_BitCast); 4288 return LHSTy; 4289 } 4290 if (RHSTy->isObjCIdType() && 4291 (LHSTy.getDesugaredType() == Context.ObjCIdRedefinitionType)) { 4292 ImpCastExprToType(LHS, RHSTy, CastExpr::CK_BitCast); 4293 return RHSTy; 4294 } 4295 // And the same for struct objc_selector* / SEL 4296 if (Context.isObjCSelType(LHSTy) && 4297 (RHSTy.getDesugaredType() == Context.ObjCSelRedefinitionType)) { 4298 ImpCastExprToType(RHS, LHSTy, CastExpr::CK_BitCast); 4299 return LHSTy; 4300 } 4301 if (Context.isObjCSelType(RHSTy) && 4302 (LHSTy.getDesugaredType() == Context.ObjCSelRedefinitionType)) { 4303 ImpCastExprToType(LHS, RHSTy, CastExpr::CK_BitCast); 4304 return RHSTy; 4305 } 4306 // Check constraints for Objective-C object pointers types. 4307 if (LHSTy->isObjCObjectPointerType() && RHSTy->isObjCObjectPointerType()) { 4308 4309 if (Context.getCanonicalType(LHSTy) == Context.getCanonicalType(RHSTy)) { 4310 // Two identical object pointer types are always compatible. 4311 return LHSTy; 4312 } 4313 const ObjCObjectPointerType *LHSOPT = LHSTy->getAs<ObjCObjectPointerType>(); 4314 const ObjCObjectPointerType *RHSOPT = RHSTy->getAs<ObjCObjectPointerType>(); 4315 QualType compositeType = LHSTy; 4316 4317 // If both operands are interfaces and either operand can be 4318 // assigned to the other, use that type as the composite 4319 // type. This allows 4320 // xxx ? (A*) a : (B*) b 4321 // where B is a subclass of A. 4322 // 4323 // Additionally, as for assignment, if either type is 'id' 4324 // allow silent coercion. Finally, if the types are 4325 // incompatible then make sure to use 'id' as the composite 4326 // type so the result is acceptable for sending messages to. 4327 4328 // FIXME: Consider unifying with 'areComparableObjCPointerTypes'. 4329 // It could return the composite type. 4330 if (Context.canAssignObjCInterfaces(LHSOPT, RHSOPT)) { 4331 compositeType = RHSOPT->isObjCBuiltinType() ? RHSTy : LHSTy; 4332 } else if (Context.canAssignObjCInterfaces(RHSOPT, LHSOPT)) { 4333 compositeType = LHSOPT->isObjCBuiltinType() ? LHSTy : RHSTy; 4334 } else if ((LHSTy->isObjCQualifiedIdType() || 4335 RHSTy->isObjCQualifiedIdType()) && 4336 Context.ObjCQualifiedIdTypesAreCompatible(LHSTy, RHSTy, true)) { 4337 // Need to handle "id<xx>" explicitly. 4338 // GCC allows qualified id and any Objective-C type to devolve to 4339 // id. Currently localizing to here until clear this should be 4340 // part of ObjCQualifiedIdTypesAreCompatible. 4341 compositeType = Context.getObjCIdType(); 4342 } else if (LHSTy->isObjCIdType() || RHSTy->isObjCIdType()) { 4343 compositeType = Context.getObjCIdType(); 4344 } else if (!(compositeType = 4345 Context.areCommonBaseCompatible(LHSOPT, RHSOPT)).isNull()) 4346 ; 4347 else { 4348 Diag(QuestionLoc, diag::ext_typecheck_cond_incompatible_operands) 4349 << LHSTy << RHSTy 4350 << LHS->getSourceRange() << RHS->getSourceRange(); 4351 QualType incompatTy = Context.getObjCIdType(); 4352 ImpCastExprToType(LHS, incompatTy, CastExpr::CK_BitCast); 4353 ImpCastExprToType(RHS, incompatTy, CastExpr::CK_BitCast); 4354 return incompatTy; 4355 } 4356 // The object pointer types are compatible. 4357 ImpCastExprToType(LHS, compositeType, CastExpr::CK_BitCast); 4358 ImpCastExprToType(RHS, compositeType, CastExpr::CK_BitCast); 4359 return compositeType; 4360 } 4361 // Check Objective-C object pointer types and 'void *' 4362 if (LHSTy->isVoidPointerType() && RHSTy->isObjCObjectPointerType()) { 4363 QualType lhptee = LHSTy->getAs<PointerType>()->getPointeeType(); 4364 QualType rhptee = RHSTy->getAs<ObjCObjectPointerType>()->getPointeeType(); 4365 QualType destPointee 4366 = Context.getQualifiedType(lhptee, rhptee.getQualifiers()); 4367 QualType destType = Context.getPointerType(destPointee); 4368 // Add qualifiers if necessary. 4369 ImpCastExprToType(LHS, destType, CastExpr::CK_NoOp); 4370 // Promote to void*. 4371 ImpCastExprToType(RHS, destType, CastExpr::CK_BitCast); 4372 return destType; 4373 } 4374 if (LHSTy->isObjCObjectPointerType() && RHSTy->isVoidPointerType()) { 4375 QualType lhptee = LHSTy->getAs<ObjCObjectPointerType>()->getPointeeType(); 4376 QualType rhptee = RHSTy->getAs<PointerType>()->getPointeeType(); 4377 QualType destPointee 4378 = Context.getQualifiedType(rhptee, lhptee.getQualifiers()); 4379 QualType destType = Context.getPointerType(destPointee); 4380 // Add qualifiers if necessary. 4381 ImpCastExprToType(RHS, destType, CastExpr::CK_NoOp); 4382 // Promote to void*. 4383 ImpCastExprToType(LHS, destType, CastExpr::CK_BitCast); 4384 return destType; 4385 } 4386 return QualType(); 4387} 4388 4389/// ActOnConditionalOp - Parse a ?: operation. Note that 'LHS' may be null 4390/// in the case of a the GNU conditional expr extension. 4391Action::OwningExprResult Sema::ActOnConditionalOp(SourceLocation QuestionLoc, 4392 SourceLocation ColonLoc, 4393 ExprArg Cond, ExprArg LHS, 4394 ExprArg RHS) { 4395 Expr *CondExpr = (Expr *) Cond.get(); 4396 Expr *LHSExpr = (Expr *) LHS.get(), *RHSExpr = (Expr *) RHS.get(); 4397 4398 // If this is the gnu "x ?: y" extension, analyze the types as though the LHS 4399 // was the condition. 4400 bool isLHSNull = LHSExpr == 0; 4401 if (isLHSNull) 4402 LHSExpr = CondExpr; 4403 4404 QualType result = CheckConditionalOperands(CondExpr, LHSExpr, 4405 RHSExpr, QuestionLoc); 4406 if (result.isNull()) 4407 return ExprError(); 4408 4409 Cond.release(); 4410 LHS.release(); 4411 RHS.release(); 4412 return Owned(new (Context) ConditionalOperator(CondExpr, QuestionLoc, 4413 isLHSNull ? 0 : LHSExpr, 4414 ColonLoc, RHSExpr, result)); 4415} 4416 4417// CheckPointerTypesForAssignment - This is a very tricky routine (despite 4418// being closely modeled after the C99 spec:-). The odd characteristic of this 4419// routine is it effectively iqnores the qualifiers on the top level pointee. 4420// This circumvents the usual type rules specified in 6.2.7p1 & 6.7.5.[1-3]. 4421// FIXME: add a couple examples in this comment. 4422Sema::AssignConvertType 4423Sema::CheckPointerTypesForAssignment(QualType lhsType, QualType rhsType) { 4424 QualType lhptee, rhptee; 4425 4426 if ((lhsType->isObjCClassType() && 4427 (rhsType.getDesugaredType() == Context.ObjCClassRedefinitionType)) || 4428 (rhsType->isObjCClassType() && 4429 (lhsType.getDesugaredType() == Context.ObjCClassRedefinitionType))) { 4430 return Compatible; 4431 } 4432 4433 // get the "pointed to" type (ignoring qualifiers at the top level) 4434 lhptee = lhsType->getAs<PointerType>()->getPointeeType(); 4435 rhptee = rhsType->getAs<PointerType>()->getPointeeType(); 4436 4437 // make sure we operate on the canonical type 4438 lhptee = Context.getCanonicalType(lhptee); 4439 rhptee = Context.getCanonicalType(rhptee); 4440 4441 AssignConvertType ConvTy = Compatible; 4442 4443 // C99 6.5.16.1p1: This following citation is common to constraints 4444 // 3 & 4 (below). ...and the type *pointed to* by the left has all the 4445 // qualifiers of the type *pointed to* by the right; 4446 // FIXME: Handle ExtQualType 4447 if (!lhptee.isAtLeastAsQualifiedAs(rhptee)) 4448 ConvTy = CompatiblePointerDiscardsQualifiers; 4449 4450 // C99 6.5.16.1p1 (constraint 4): If one operand is a pointer to an object or 4451 // incomplete type and the other is a pointer to a qualified or unqualified 4452 // version of void... 4453 if (lhptee->isVoidType()) { 4454 if (rhptee->isIncompleteOrObjectType()) 4455 return ConvTy; 4456 4457 // As an extension, we allow cast to/from void* to function pointer. 4458 assert(rhptee->isFunctionType()); 4459 return FunctionVoidPointer; 4460 } 4461 4462 if (rhptee->isVoidType()) { 4463 if (lhptee->isIncompleteOrObjectType()) 4464 return ConvTy; 4465 4466 // As an extension, we allow cast to/from void* to function pointer. 4467 assert(lhptee->isFunctionType()); 4468 return FunctionVoidPointer; 4469 } 4470 // C99 6.5.16.1p1 (constraint 3): both operands are pointers to qualified or 4471 // unqualified versions of compatible types, ... 4472 lhptee = lhptee.getUnqualifiedType(); 4473 rhptee = rhptee.getUnqualifiedType(); 4474 if (!Context.typesAreCompatible(lhptee, rhptee)) { 4475 // Check if the pointee types are compatible ignoring the sign. 4476 // We explicitly check for char so that we catch "char" vs 4477 // "unsigned char" on systems where "char" is unsigned. 4478 if (lhptee->isCharType()) 4479 lhptee = Context.UnsignedCharTy; 4480 else if (lhptee->isSignedIntegerType()) 4481 lhptee = Context.getCorrespondingUnsignedType(lhptee); 4482 4483 if (rhptee->isCharType()) 4484 rhptee = Context.UnsignedCharTy; 4485 else if (rhptee->isSignedIntegerType()) 4486 rhptee = Context.getCorrespondingUnsignedType(rhptee); 4487 4488 if (lhptee == rhptee) { 4489 // Types are compatible ignoring the sign. Qualifier incompatibility 4490 // takes priority over sign incompatibility because the sign 4491 // warning can be disabled. 4492 if (ConvTy != Compatible) 4493 return ConvTy; 4494 return IncompatiblePointerSign; 4495 } 4496 4497 // If we are a multi-level pointer, it's possible that our issue is simply 4498 // one of qualification - e.g. char ** -> const char ** is not allowed. If 4499 // the eventual target type is the same and the pointers have the same 4500 // level of indirection, this must be the issue. 4501 if (lhptee->isPointerType() && rhptee->isPointerType()) { 4502 do { 4503 lhptee = lhptee->getAs<PointerType>()->getPointeeType(); 4504 rhptee = rhptee->getAs<PointerType>()->getPointeeType(); 4505 4506 lhptee = Context.getCanonicalType(lhptee); 4507 rhptee = Context.getCanonicalType(rhptee); 4508 } while (lhptee->isPointerType() && rhptee->isPointerType()); 4509 4510 if (Context.hasSameUnqualifiedType(lhptee, rhptee)) 4511 return IncompatibleNestedPointerQualifiers; 4512 } 4513 4514 // General pointer incompatibility takes priority over qualifiers. 4515 return IncompatiblePointer; 4516 } 4517 return ConvTy; 4518} 4519 4520/// CheckBlockPointerTypesForAssignment - This routine determines whether two 4521/// block pointer types are compatible or whether a block and normal pointer 4522/// are compatible. It is more restrict than comparing two function pointer 4523// types. 4524Sema::AssignConvertType 4525Sema::CheckBlockPointerTypesForAssignment(QualType lhsType, 4526 QualType rhsType) { 4527 QualType lhptee, rhptee; 4528 4529 // get the "pointed to" type (ignoring qualifiers at the top level) 4530 lhptee = lhsType->getAs<BlockPointerType>()->getPointeeType(); 4531 rhptee = rhsType->getAs<BlockPointerType>()->getPointeeType(); 4532 4533 // make sure we operate on the canonical type 4534 lhptee = Context.getCanonicalType(lhptee); 4535 rhptee = Context.getCanonicalType(rhptee); 4536 4537 AssignConvertType ConvTy = Compatible; 4538 4539 // For blocks we enforce that qualifiers are identical. 4540 if (lhptee.getLocalCVRQualifiers() != rhptee.getLocalCVRQualifiers()) 4541 ConvTy = CompatiblePointerDiscardsQualifiers; 4542 4543 if (!getLangOptions().CPlusPlus) { 4544 if (!Context.typesAreBlockPointerCompatible(lhsType, rhsType)) 4545 return IncompatibleBlockPointer; 4546 } 4547 else if (!Context.typesAreCompatible(lhptee, rhptee)) 4548 return IncompatibleBlockPointer; 4549 return ConvTy; 4550} 4551 4552/// CheckObjCPointerTypesForAssignment - Compares two objective-c pointer types 4553/// for assignment compatibility. 4554Sema::AssignConvertType 4555Sema::CheckObjCPointerTypesForAssignment(QualType lhsType, QualType rhsType) { 4556 if (lhsType->isObjCBuiltinType()) { 4557 // Class is not compatible with ObjC object pointers. 4558 if (lhsType->isObjCClassType() && !rhsType->isObjCBuiltinType() && 4559 !rhsType->isObjCQualifiedClassType()) 4560 return IncompatiblePointer; 4561 return Compatible; 4562 } 4563 if (rhsType->isObjCBuiltinType()) { 4564 // Class is not compatible with ObjC object pointers. 4565 if (rhsType->isObjCClassType() && !lhsType->isObjCBuiltinType() && 4566 !lhsType->isObjCQualifiedClassType()) 4567 return IncompatiblePointer; 4568 return Compatible; 4569 } 4570 QualType lhptee = 4571 lhsType->getAs<ObjCObjectPointerType>()->getPointeeType(); 4572 QualType rhptee = 4573 rhsType->getAs<ObjCObjectPointerType>()->getPointeeType(); 4574 // make sure we operate on the canonical type 4575 lhptee = Context.getCanonicalType(lhptee); 4576 rhptee = Context.getCanonicalType(rhptee); 4577 if (!lhptee.isAtLeastAsQualifiedAs(rhptee)) 4578 return CompatiblePointerDiscardsQualifiers; 4579 4580 if (Context.typesAreCompatible(lhsType, rhsType)) 4581 return Compatible; 4582 if (lhsType->isObjCQualifiedIdType() || rhsType->isObjCQualifiedIdType()) 4583 return IncompatibleObjCQualifiedId; 4584 return IncompatiblePointer; 4585} 4586 4587/// CheckAssignmentConstraints (C99 6.5.16) - This routine currently 4588/// has code to accommodate several GCC extensions when type checking 4589/// pointers. Here are some objectionable examples that GCC considers warnings: 4590/// 4591/// int a, *pint; 4592/// short *pshort; 4593/// struct foo *pfoo; 4594/// 4595/// pint = pshort; // warning: assignment from incompatible pointer type 4596/// a = pint; // warning: assignment makes integer from pointer without a cast 4597/// pint = a; // warning: assignment makes pointer from integer without a cast 4598/// pint = pfoo; // warning: assignment from incompatible pointer type 4599/// 4600/// As a result, the code for dealing with pointers is more complex than the 4601/// C99 spec dictates. 4602/// 4603Sema::AssignConvertType 4604Sema::CheckAssignmentConstraints(QualType lhsType, QualType rhsType) { 4605 // Get canonical types. We're not formatting these types, just comparing 4606 // them. 4607 lhsType = Context.getCanonicalType(lhsType).getUnqualifiedType(); 4608 rhsType = Context.getCanonicalType(rhsType).getUnqualifiedType(); 4609 4610 if (lhsType == rhsType) 4611 return Compatible; // Common case: fast path an exact match. 4612 4613 if ((lhsType->isObjCClassType() && 4614 (rhsType.getDesugaredType() == Context.ObjCClassRedefinitionType)) || 4615 (rhsType->isObjCClassType() && 4616 (lhsType.getDesugaredType() == Context.ObjCClassRedefinitionType))) { 4617 return Compatible; 4618 } 4619 4620 // If the left-hand side is a reference type, then we are in a 4621 // (rare!) case where we've allowed the use of references in C, 4622 // e.g., as a parameter type in a built-in function. In this case, 4623 // just make sure that the type referenced is compatible with the 4624 // right-hand side type. The caller is responsible for adjusting 4625 // lhsType so that the resulting expression does not have reference 4626 // type. 4627 if (const ReferenceType *lhsTypeRef = lhsType->getAs<ReferenceType>()) { 4628 if (Context.typesAreCompatible(lhsTypeRef->getPointeeType(), rhsType)) 4629 return Compatible; 4630 return Incompatible; 4631 } 4632 // Allow scalar to ExtVector assignments, and assignments of an ExtVector type 4633 // to the same ExtVector type. 4634 if (lhsType->isExtVectorType()) { 4635 if (rhsType->isExtVectorType()) 4636 return lhsType == rhsType ? Compatible : Incompatible; 4637 if (!rhsType->isVectorType() && rhsType->isArithmeticType()) 4638 return Compatible; 4639 } 4640 4641 if (lhsType->isVectorType() || rhsType->isVectorType()) { 4642 // If we are allowing lax vector conversions, and LHS and RHS are both 4643 // vectors, the total size only needs to be the same. This is a bitcast; 4644 // no bits are changed but the result type is different. 4645 if (getLangOptions().LaxVectorConversions && 4646 lhsType->isVectorType() && rhsType->isVectorType()) { 4647 if (Context.getTypeSize(lhsType) == Context.getTypeSize(rhsType)) 4648 return IncompatibleVectors; 4649 } 4650 return Incompatible; 4651 } 4652 4653 if (lhsType->isArithmeticType() && rhsType->isArithmeticType() && 4654 !(getLangOptions().CPlusPlus && lhsType->isEnumeralType())) 4655 return Compatible; 4656 4657 if (isa<PointerType>(lhsType)) { 4658 if (rhsType->isIntegerType()) 4659 return IntToPointer; 4660 4661 if (isa<PointerType>(rhsType)) 4662 return CheckPointerTypesForAssignment(lhsType, rhsType); 4663 4664 // In general, C pointers are not compatible with ObjC object pointers. 4665 if (isa<ObjCObjectPointerType>(rhsType)) { 4666 if (lhsType->isVoidPointerType()) // an exception to the rule. 4667 return Compatible; 4668 return IncompatiblePointer; 4669 } 4670 if (rhsType->getAs<BlockPointerType>()) { 4671 if (lhsType->getAs<PointerType>()->getPointeeType()->isVoidType()) 4672 return Compatible; 4673 4674 // Treat block pointers as objects. 4675 if (getLangOptions().ObjC1 && lhsType->isObjCIdType()) 4676 return Compatible; 4677 } 4678 return Incompatible; 4679 } 4680 4681 if (isa<BlockPointerType>(lhsType)) { 4682 if (rhsType->isIntegerType()) 4683 return IntToBlockPointer; 4684 4685 // Treat block pointers as objects. 4686 if (getLangOptions().ObjC1 && rhsType->isObjCIdType()) 4687 return Compatible; 4688 4689 if (rhsType->isBlockPointerType()) 4690 return CheckBlockPointerTypesForAssignment(lhsType, rhsType); 4691 4692 if (const PointerType *RHSPT = rhsType->getAs<PointerType>()) { 4693 if (RHSPT->getPointeeType()->isVoidType()) 4694 return Compatible; 4695 } 4696 return Incompatible; 4697 } 4698 4699 if (isa<ObjCObjectPointerType>(lhsType)) { 4700 if (rhsType->isIntegerType()) 4701 return IntToPointer; 4702 4703 // In general, C pointers are not compatible with ObjC object pointers. 4704 if (isa<PointerType>(rhsType)) { 4705 if (rhsType->isVoidPointerType()) // an exception to the rule. 4706 return Compatible; 4707 return IncompatiblePointer; 4708 } 4709 if (rhsType->isObjCObjectPointerType()) { 4710 return CheckObjCPointerTypesForAssignment(lhsType, rhsType); 4711 } 4712 if (const PointerType *RHSPT = rhsType->getAs<PointerType>()) { 4713 if (RHSPT->getPointeeType()->isVoidType()) 4714 return Compatible; 4715 } 4716 // Treat block pointers as objects. 4717 if (rhsType->isBlockPointerType()) 4718 return Compatible; 4719 return Incompatible; 4720 } 4721 if (isa<PointerType>(rhsType)) { 4722 // C99 6.5.16.1p1: the left operand is _Bool and the right is a pointer. 4723 if (lhsType == Context.BoolTy) 4724 return Compatible; 4725 4726 if (lhsType->isIntegerType()) 4727 return PointerToInt; 4728 4729 if (isa<PointerType>(lhsType)) 4730 return CheckPointerTypesForAssignment(lhsType, rhsType); 4731 4732 if (isa<BlockPointerType>(lhsType) && 4733 rhsType->getAs<PointerType>()->getPointeeType()->isVoidType()) 4734 return Compatible; 4735 return Incompatible; 4736 } 4737 if (isa<ObjCObjectPointerType>(rhsType)) { 4738 // C99 6.5.16.1p1: the left operand is _Bool and the right is a pointer. 4739 if (lhsType == Context.BoolTy) 4740 return Compatible; 4741 4742 if (lhsType->isIntegerType()) 4743 return PointerToInt; 4744 4745 // In general, C pointers are not compatible with ObjC object pointers. 4746 if (isa<PointerType>(lhsType)) { 4747 if (lhsType->isVoidPointerType()) // an exception to the rule. 4748 return Compatible; 4749 return IncompatiblePointer; 4750 } 4751 if (isa<BlockPointerType>(lhsType) && 4752 rhsType->getAs<PointerType>()->getPointeeType()->isVoidType()) 4753 return Compatible; 4754 return Incompatible; 4755 } 4756 4757 if (isa<TagType>(lhsType) && isa<TagType>(rhsType)) { 4758 if (Context.typesAreCompatible(lhsType, rhsType)) 4759 return Compatible; 4760 } 4761 return Incompatible; 4762} 4763 4764/// \brief Constructs a transparent union from an expression that is 4765/// used to initialize the transparent union. 4766static void ConstructTransparentUnion(ASTContext &C, Expr *&E, 4767 QualType UnionType, FieldDecl *Field) { 4768 // Build an initializer list that designates the appropriate member 4769 // of the transparent union. 4770 InitListExpr *Initializer = new (C) InitListExpr(C, SourceLocation(), 4771 &E, 1, 4772 SourceLocation()); 4773 Initializer->setType(UnionType); 4774 Initializer->setInitializedFieldInUnion(Field); 4775 4776 // Build a compound literal constructing a value of the transparent 4777 // union type from this initializer list. 4778 TypeSourceInfo *unionTInfo = C.getTrivialTypeSourceInfo(UnionType); 4779 E = new (C) CompoundLiteralExpr(SourceLocation(), unionTInfo, UnionType, 4780 Initializer, false); 4781} 4782 4783Sema::AssignConvertType 4784Sema::CheckTransparentUnionArgumentConstraints(QualType ArgType, Expr *&rExpr) { 4785 QualType FromType = rExpr->getType(); 4786 4787 // If the ArgType is a Union type, we want to handle a potential 4788 // transparent_union GCC extension. 4789 const RecordType *UT = ArgType->getAsUnionType(); 4790 if (!UT || !UT->getDecl()->hasAttr<TransparentUnionAttr>()) 4791 return Incompatible; 4792 4793 // The field to initialize within the transparent union. 4794 RecordDecl *UD = UT->getDecl(); 4795 FieldDecl *InitField = 0; 4796 // It's compatible if the expression matches any of the fields. 4797 for (RecordDecl::field_iterator it = UD->field_begin(), 4798 itend = UD->field_end(); 4799 it != itend; ++it) { 4800 if (it->getType()->isPointerType()) { 4801 // If the transparent union contains a pointer type, we allow: 4802 // 1) void pointer 4803 // 2) null pointer constant 4804 if (FromType->isPointerType()) 4805 if (FromType->getAs<PointerType>()->getPointeeType()->isVoidType()) { 4806 ImpCastExprToType(rExpr, it->getType(), CastExpr::CK_BitCast); 4807 InitField = *it; 4808 break; 4809 } 4810 4811 if (rExpr->isNullPointerConstant(Context, 4812 Expr::NPC_ValueDependentIsNull)) { 4813 ImpCastExprToType(rExpr, it->getType(), CastExpr::CK_IntegralToPointer); 4814 InitField = *it; 4815 break; 4816 } 4817 } 4818 4819 if (CheckAssignmentConstraints(it->getType(), rExpr->getType()) 4820 == Compatible) { 4821 InitField = *it; 4822 break; 4823 } 4824 } 4825 4826 if (!InitField) 4827 return Incompatible; 4828 4829 ConstructTransparentUnion(Context, rExpr, ArgType, InitField); 4830 return Compatible; 4831} 4832 4833Sema::AssignConvertType 4834Sema::CheckSingleAssignmentConstraints(QualType lhsType, Expr *&rExpr) { 4835 if (getLangOptions().CPlusPlus) { 4836 if (!lhsType->isRecordType()) { 4837 // C++ 5.17p3: If the left operand is not of class type, the 4838 // expression is implicitly converted (C++ 4) to the 4839 // cv-unqualified type of the left operand. 4840 if (PerformImplicitConversion(rExpr, lhsType.getUnqualifiedType(), 4841 AA_Assigning)) 4842 return Incompatible; 4843 return Compatible; 4844 } 4845 4846 // FIXME: Currently, we fall through and treat C++ classes like C 4847 // structures. 4848 } 4849 4850 // C99 6.5.16.1p1: the left operand is a pointer and the right is 4851 // a null pointer constant. 4852 if ((lhsType->isPointerType() || 4853 lhsType->isObjCObjectPointerType() || 4854 lhsType->isBlockPointerType()) 4855 && rExpr->isNullPointerConstant(Context, 4856 Expr::NPC_ValueDependentIsNull)) { 4857 ImpCastExprToType(rExpr, lhsType, CastExpr::CK_Unknown); 4858 return Compatible; 4859 } 4860 4861 // This check seems unnatural, however it is necessary to ensure the proper 4862 // conversion of functions/arrays. If the conversion were done for all 4863 // DeclExpr's (created by ActOnIdExpression), it would mess up the unary 4864 // expressions that surpress this implicit conversion (&, sizeof). 4865 // 4866 // Suppress this for references: C++ 8.5.3p5. 4867 if (!lhsType->isReferenceType()) 4868 DefaultFunctionArrayLvalueConversion(rExpr); 4869 4870 Sema::AssignConvertType result = 4871 CheckAssignmentConstraints(lhsType, rExpr->getType()); 4872 4873 // C99 6.5.16.1p2: The value of the right operand is converted to the 4874 // type of the assignment expression. 4875 // CheckAssignmentConstraints allows the left-hand side to be a reference, 4876 // so that we can use references in built-in functions even in C. 4877 // The getNonReferenceType() call makes sure that the resulting expression 4878 // does not have reference type. 4879 if (result != Incompatible && rExpr->getType() != lhsType) 4880 ImpCastExprToType(rExpr, lhsType.getNonReferenceType(), 4881 CastExpr::CK_Unknown); 4882 return result; 4883} 4884 4885QualType Sema::InvalidOperands(SourceLocation Loc, Expr *&lex, Expr *&rex) { 4886 Diag(Loc, diag::err_typecheck_invalid_operands) 4887 << lex->getType() << rex->getType() 4888 << lex->getSourceRange() << rex->getSourceRange(); 4889 return QualType(); 4890} 4891 4892QualType Sema::CheckVectorOperands(SourceLocation Loc, Expr *&lex, Expr *&rex) { 4893 // For conversion purposes, we ignore any qualifiers. 4894 // For example, "const float" and "float" are equivalent. 4895 QualType lhsType = 4896 Context.getCanonicalType(lex->getType()).getUnqualifiedType(); 4897 QualType rhsType = 4898 Context.getCanonicalType(rex->getType()).getUnqualifiedType(); 4899 4900 // If the vector types are identical, return. 4901 if (lhsType == rhsType) 4902 return lhsType; 4903 4904 // Handle the case of a vector & extvector type of the same size and element 4905 // type. It would be nice if we only had one vector type someday. 4906 if (getLangOptions().LaxVectorConversions) { 4907 // FIXME: Should we warn here? 4908 if (const VectorType *LV = lhsType->getAs<VectorType>()) { 4909 if (const VectorType *RV = rhsType->getAs<VectorType>()) 4910 if (LV->getElementType() == RV->getElementType() && 4911 LV->getNumElements() == RV->getNumElements()) { 4912 if (lhsType->isExtVectorType()) { 4913 ImpCastExprToType(rex, lhsType, CastExpr::CK_BitCast); 4914 return lhsType; 4915 } 4916 4917 ImpCastExprToType(lex, rhsType, CastExpr::CK_BitCast); 4918 return rhsType; 4919 } 4920 } 4921 } 4922 4923 // Canonicalize the ExtVector to the LHS, remember if we swapped so we can 4924 // swap back (so that we don't reverse the inputs to a subtract, for instance. 4925 bool swapped = false; 4926 if (rhsType->isExtVectorType()) { 4927 swapped = true; 4928 std::swap(rex, lex); 4929 std::swap(rhsType, lhsType); 4930 } 4931 4932 // Handle the case of an ext vector and scalar. 4933 if (const ExtVectorType *LV = lhsType->getAs<ExtVectorType>()) { 4934 QualType EltTy = LV->getElementType(); 4935 if (EltTy->isIntegralType() && rhsType->isIntegralType()) { 4936 if (Context.getIntegerTypeOrder(EltTy, rhsType) >= 0) { 4937 ImpCastExprToType(rex, lhsType, CastExpr::CK_IntegralCast); 4938 if (swapped) std::swap(rex, lex); 4939 return lhsType; 4940 } 4941 } 4942 if (EltTy->isRealFloatingType() && rhsType->isScalarType() && 4943 rhsType->isRealFloatingType()) { 4944 if (Context.getFloatingTypeOrder(EltTy, rhsType) >= 0) { 4945 ImpCastExprToType(rex, lhsType, CastExpr::CK_FloatingCast); 4946 if (swapped) std::swap(rex, lex); 4947 return lhsType; 4948 } 4949 } 4950 } 4951 4952 // Vectors of different size or scalar and non-ext-vector are errors. 4953 Diag(Loc, diag::err_typecheck_vector_not_convertable) 4954 << lex->getType() << rex->getType() 4955 << lex->getSourceRange() << rex->getSourceRange(); 4956 return QualType(); 4957} 4958 4959QualType Sema::CheckMultiplyDivideOperands( 4960 Expr *&lex, Expr *&rex, SourceLocation Loc, bool isCompAssign, bool isDiv) { 4961 if (lex->getType()->isVectorType() || rex->getType()->isVectorType()) 4962 return CheckVectorOperands(Loc, lex, rex); 4963 4964 QualType compType = UsualArithmeticConversions(lex, rex, isCompAssign); 4965 4966 if (!lex->getType()->isArithmeticType() || 4967 !rex->getType()->isArithmeticType()) 4968 return InvalidOperands(Loc, lex, rex); 4969 4970 // Check for division by zero. 4971 if (isDiv && 4972 rex->isNullPointerConstant(Context, Expr::NPC_ValueDependentIsNotNull)) 4973 DiagRuntimeBehavior(Loc, PDiag(diag::warn_division_by_zero) 4974 << rex->getSourceRange()); 4975 4976 return compType; 4977} 4978 4979QualType Sema::CheckRemainderOperands( 4980 Expr *&lex, Expr *&rex, SourceLocation Loc, bool isCompAssign) { 4981 if (lex->getType()->isVectorType() || rex->getType()->isVectorType()) { 4982 if (lex->getType()->isIntegerType() && rex->getType()->isIntegerType()) 4983 return CheckVectorOperands(Loc, lex, rex); 4984 return InvalidOperands(Loc, lex, rex); 4985 } 4986 4987 QualType compType = UsualArithmeticConversions(lex, rex, isCompAssign); 4988 4989 if (!lex->getType()->isIntegerType() || !rex->getType()->isIntegerType()) 4990 return InvalidOperands(Loc, lex, rex); 4991 4992 // Check for remainder by zero. 4993 if (rex->isNullPointerConstant(Context, Expr::NPC_ValueDependentIsNotNull)) 4994 DiagRuntimeBehavior(Loc, PDiag(diag::warn_remainder_by_zero) 4995 << rex->getSourceRange()); 4996 4997 return compType; 4998} 4999 5000QualType Sema::CheckAdditionOperands( // C99 6.5.6 5001 Expr *&lex, Expr *&rex, SourceLocation Loc, QualType* CompLHSTy) { 5002 if (lex->getType()->isVectorType() || rex->getType()->isVectorType()) { 5003 QualType compType = CheckVectorOperands(Loc, lex, rex); 5004 if (CompLHSTy) *CompLHSTy = compType; 5005 return compType; 5006 } 5007 5008 QualType compType = UsualArithmeticConversions(lex, rex, CompLHSTy); 5009 5010 // handle the common case first (both operands are arithmetic). 5011 if (lex->getType()->isArithmeticType() && 5012 rex->getType()->isArithmeticType()) { 5013 if (CompLHSTy) *CompLHSTy = compType; 5014 return compType; 5015 } 5016 5017 // Put any potential pointer into PExp 5018 Expr* PExp = lex, *IExp = rex; 5019 if (IExp->getType()->isAnyPointerType()) 5020 std::swap(PExp, IExp); 5021 5022 if (PExp->getType()->isAnyPointerType()) { 5023 5024 if (IExp->getType()->isIntegerType()) { 5025 QualType PointeeTy = PExp->getType()->getPointeeType(); 5026 5027 // Check for arithmetic on pointers to incomplete types. 5028 if (PointeeTy->isVoidType()) { 5029 if (getLangOptions().CPlusPlus) { 5030 Diag(Loc, diag::err_typecheck_pointer_arith_void_type) 5031 << lex->getSourceRange() << rex->getSourceRange(); 5032 return QualType(); 5033 } 5034 5035 // GNU extension: arithmetic on pointer to void 5036 Diag(Loc, diag::ext_gnu_void_ptr) 5037 << lex->getSourceRange() << rex->getSourceRange(); 5038 } else if (PointeeTy->isFunctionType()) { 5039 if (getLangOptions().CPlusPlus) { 5040 Diag(Loc, diag::err_typecheck_pointer_arith_function_type) 5041 << lex->getType() << lex->getSourceRange(); 5042 return QualType(); 5043 } 5044 5045 // GNU extension: arithmetic on pointer to function 5046 Diag(Loc, diag::ext_gnu_ptr_func_arith) 5047 << lex->getType() << lex->getSourceRange(); 5048 } else { 5049 // Check if we require a complete type. 5050 if (((PExp->getType()->isPointerType() && 5051 !PExp->getType()->isDependentType()) || 5052 PExp->getType()->isObjCObjectPointerType()) && 5053 RequireCompleteType(Loc, PointeeTy, 5054 PDiag(diag::err_typecheck_arithmetic_incomplete_type) 5055 << PExp->getSourceRange() 5056 << PExp->getType())) 5057 return QualType(); 5058 } 5059 // Diagnose bad cases where we step over interface counts. 5060 if (PointeeTy->isObjCObjectType() && LangOpts.ObjCNonFragileABI) { 5061 Diag(Loc, diag::err_arithmetic_nonfragile_interface) 5062 << PointeeTy << PExp->getSourceRange(); 5063 return QualType(); 5064 } 5065 5066 if (CompLHSTy) { 5067 QualType LHSTy = Context.isPromotableBitField(lex); 5068 if (LHSTy.isNull()) { 5069 LHSTy = lex->getType(); 5070 if (LHSTy->isPromotableIntegerType()) 5071 LHSTy = Context.getPromotedIntegerType(LHSTy); 5072 } 5073 *CompLHSTy = LHSTy; 5074 } 5075 return PExp->getType(); 5076 } 5077 } 5078 5079 return InvalidOperands(Loc, lex, rex); 5080} 5081 5082// C99 6.5.6 5083QualType Sema::CheckSubtractionOperands(Expr *&lex, Expr *&rex, 5084 SourceLocation Loc, QualType* CompLHSTy) { 5085 if (lex->getType()->isVectorType() || rex->getType()->isVectorType()) { 5086 QualType compType = CheckVectorOperands(Loc, lex, rex); 5087 if (CompLHSTy) *CompLHSTy = compType; 5088 return compType; 5089 } 5090 5091 QualType compType = UsualArithmeticConversions(lex, rex, CompLHSTy); 5092 5093 // Enforce type constraints: C99 6.5.6p3. 5094 5095 // Handle the common case first (both operands are arithmetic). 5096 if (lex->getType()->isArithmeticType() 5097 && rex->getType()->isArithmeticType()) { 5098 if (CompLHSTy) *CompLHSTy = compType; 5099 return compType; 5100 } 5101 5102 // Either ptr - int or ptr - ptr. 5103 if (lex->getType()->isAnyPointerType()) { 5104 QualType lpointee = lex->getType()->getPointeeType(); 5105 5106 // The LHS must be an completely-defined object type. 5107 5108 bool ComplainAboutVoid = false; 5109 Expr *ComplainAboutFunc = 0; 5110 if (lpointee->isVoidType()) { 5111 if (getLangOptions().CPlusPlus) { 5112 Diag(Loc, diag::err_typecheck_pointer_arith_void_type) 5113 << lex->getSourceRange() << rex->getSourceRange(); 5114 return QualType(); 5115 } 5116 5117 // GNU C extension: arithmetic on pointer to void 5118 ComplainAboutVoid = true; 5119 } else if (lpointee->isFunctionType()) { 5120 if (getLangOptions().CPlusPlus) { 5121 Diag(Loc, diag::err_typecheck_pointer_arith_function_type) 5122 << lex->getType() << lex->getSourceRange(); 5123 return QualType(); 5124 } 5125 5126 // GNU C extension: arithmetic on pointer to function 5127 ComplainAboutFunc = lex; 5128 } else if (!lpointee->isDependentType() && 5129 RequireCompleteType(Loc, lpointee, 5130 PDiag(diag::err_typecheck_sub_ptr_object) 5131 << lex->getSourceRange() 5132 << lex->getType())) 5133 return QualType(); 5134 5135 // Diagnose bad cases where we step over interface counts. 5136 if (lpointee->isObjCObjectType() && LangOpts.ObjCNonFragileABI) { 5137 Diag(Loc, diag::err_arithmetic_nonfragile_interface) 5138 << lpointee << lex->getSourceRange(); 5139 return QualType(); 5140 } 5141 5142 // The result type of a pointer-int computation is the pointer type. 5143 if (rex->getType()->isIntegerType()) { 5144 if (ComplainAboutVoid) 5145 Diag(Loc, diag::ext_gnu_void_ptr) 5146 << lex->getSourceRange() << rex->getSourceRange(); 5147 if (ComplainAboutFunc) 5148 Diag(Loc, diag::ext_gnu_ptr_func_arith) 5149 << ComplainAboutFunc->getType() 5150 << ComplainAboutFunc->getSourceRange(); 5151 5152 if (CompLHSTy) *CompLHSTy = lex->getType(); 5153 return lex->getType(); 5154 } 5155 5156 // Handle pointer-pointer subtractions. 5157 if (const PointerType *RHSPTy = rex->getType()->getAs<PointerType>()) { 5158 QualType rpointee = RHSPTy->getPointeeType(); 5159 5160 // RHS must be a completely-type object type. 5161 // Handle the GNU void* extension. 5162 if (rpointee->isVoidType()) { 5163 if (getLangOptions().CPlusPlus) { 5164 Diag(Loc, diag::err_typecheck_pointer_arith_void_type) 5165 << lex->getSourceRange() << rex->getSourceRange(); 5166 return QualType(); 5167 } 5168 5169 ComplainAboutVoid = true; 5170 } else if (rpointee->isFunctionType()) { 5171 if (getLangOptions().CPlusPlus) { 5172 Diag(Loc, diag::err_typecheck_pointer_arith_function_type) 5173 << rex->getType() << rex->getSourceRange(); 5174 return QualType(); 5175 } 5176 5177 // GNU extension: arithmetic on pointer to function 5178 if (!ComplainAboutFunc) 5179 ComplainAboutFunc = rex; 5180 } else if (!rpointee->isDependentType() && 5181 RequireCompleteType(Loc, rpointee, 5182 PDiag(diag::err_typecheck_sub_ptr_object) 5183 << rex->getSourceRange() 5184 << rex->getType())) 5185 return QualType(); 5186 5187 if (getLangOptions().CPlusPlus) { 5188 // Pointee types must be the same: C++ [expr.add] 5189 if (!Context.hasSameUnqualifiedType(lpointee, rpointee)) { 5190 Diag(Loc, diag::err_typecheck_sub_ptr_compatible) 5191 << lex->getType() << rex->getType() 5192 << lex->getSourceRange() << rex->getSourceRange(); 5193 return QualType(); 5194 } 5195 } else { 5196 // Pointee types must be compatible C99 6.5.6p3 5197 if (!Context.typesAreCompatible( 5198 Context.getCanonicalType(lpointee).getUnqualifiedType(), 5199 Context.getCanonicalType(rpointee).getUnqualifiedType())) { 5200 Diag(Loc, diag::err_typecheck_sub_ptr_compatible) 5201 << lex->getType() << rex->getType() 5202 << lex->getSourceRange() << rex->getSourceRange(); 5203 return QualType(); 5204 } 5205 } 5206 5207 if (ComplainAboutVoid) 5208 Diag(Loc, diag::ext_gnu_void_ptr) 5209 << lex->getSourceRange() << rex->getSourceRange(); 5210 if (ComplainAboutFunc) 5211 Diag(Loc, diag::ext_gnu_ptr_func_arith) 5212 << ComplainAboutFunc->getType() 5213 << ComplainAboutFunc->getSourceRange(); 5214 5215 if (CompLHSTy) *CompLHSTy = lex->getType(); 5216 return Context.getPointerDiffType(); 5217 } 5218 } 5219 5220 return InvalidOperands(Loc, lex, rex); 5221} 5222 5223// C99 6.5.7 5224QualType Sema::CheckShiftOperands(Expr *&lex, Expr *&rex, SourceLocation Loc, 5225 bool isCompAssign) { 5226 // C99 6.5.7p2: Each of the operands shall have integer type. 5227 if (!lex->getType()->isIntegerType() || !rex->getType()->isIntegerType()) 5228 return InvalidOperands(Loc, lex, rex); 5229 5230 // Vector shifts promote their scalar inputs to vector type. 5231 if (lex->getType()->isVectorType() || rex->getType()->isVectorType()) 5232 return CheckVectorOperands(Loc, lex, rex); 5233 5234 // Shifts don't perform usual arithmetic conversions, they just do integer 5235 // promotions on each operand. C99 6.5.7p3 5236 QualType LHSTy = Context.isPromotableBitField(lex); 5237 if (LHSTy.isNull()) { 5238 LHSTy = lex->getType(); 5239 if (LHSTy->isPromotableIntegerType()) 5240 LHSTy = Context.getPromotedIntegerType(LHSTy); 5241 } 5242 if (!isCompAssign) 5243 ImpCastExprToType(lex, LHSTy, CastExpr::CK_IntegralCast); 5244 5245 UsualUnaryConversions(rex); 5246 5247 // Sanity-check shift operands 5248 llvm::APSInt Right; 5249 // Check right/shifter operand 5250 if (!rex->isValueDependent() && 5251 rex->isIntegerConstantExpr(Right, Context)) { 5252 if (Right.isNegative()) 5253 Diag(Loc, diag::warn_shift_negative) << rex->getSourceRange(); 5254 else { 5255 llvm::APInt LeftBits(Right.getBitWidth(), 5256 Context.getTypeSize(lex->getType())); 5257 if (Right.uge(LeftBits)) 5258 Diag(Loc, diag::warn_shift_gt_typewidth) << rex->getSourceRange(); 5259 } 5260 } 5261 5262 // "The type of the result is that of the promoted left operand." 5263 return LHSTy; 5264} 5265 5266// C99 6.5.8, C++ [expr.rel] 5267QualType Sema::CheckCompareOperands(Expr *&lex, Expr *&rex, SourceLocation Loc, 5268 unsigned OpaqueOpc, bool isRelational) { 5269 BinaryOperator::Opcode Opc = (BinaryOperator::Opcode)OpaqueOpc; 5270 5271 // Handle vector comparisons separately. 5272 if (lex->getType()->isVectorType() || rex->getType()->isVectorType()) 5273 return CheckVectorCompareOperands(lex, rex, Loc, isRelational); 5274 5275 // C99 6.5.8p3 / C99 6.5.9p4 5276 if (lex->getType()->isArithmeticType() && rex->getType()->isArithmeticType()) 5277 UsualArithmeticConversions(lex, rex); 5278 else { 5279 UsualUnaryConversions(lex); 5280 UsualUnaryConversions(rex); 5281 } 5282 QualType lType = lex->getType(); 5283 QualType rType = rex->getType(); 5284 5285 if (!lType->isFloatingType() 5286 && !(lType->isBlockPointerType() && isRelational)) { 5287 // For non-floating point types, check for self-comparisons of the form 5288 // x == x, x != x, x < x, etc. These always evaluate to a constant, and 5289 // often indicate logic errors in the program. 5290 // NOTE: Don't warn about comparisons of enum constants. These can arise 5291 // from macro expansions, and are usually quite deliberate. 5292 Expr *LHSStripped = lex->IgnoreParens(); 5293 Expr *RHSStripped = rex->IgnoreParens(); 5294 if (DeclRefExpr* DRL = dyn_cast<DeclRefExpr>(LHSStripped)) 5295 if (DeclRefExpr* DRR = dyn_cast<DeclRefExpr>(RHSStripped)) 5296 if (DRL->getDecl() == DRR->getDecl() && 5297 !isa<EnumConstantDecl>(DRL->getDecl())) 5298 DiagRuntimeBehavior(Loc, PDiag(diag::warn_selfcomparison)); 5299 5300 if (isa<CastExpr>(LHSStripped)) 5301 LHSStripped = LHSStripped->IgnoreParenCasts(); 5302 if (isa<CastExpr>(RHSStripped)) 5303 RHSStripped = RHSStripped->IgnoreParenCasts(); 5304 5305 // Warn about comparisons against a string constant (unless the other 5306 // operand is null), the user probably wants strcmp. 5307 Expr *literalString = 0; 5308 Expr *literalStringStripped = 0; 5309 if ((isa<StringLiteral>(LHSStripped) || isa<ObjCEncodeExpr>(LHSStripped)) && 5310 !RHSStripped->isNullPointerConstant(Context, 5311 Expr::NPC_ValueDependentIsNull)) { 5312 literalString = lex; 5313 literalStringStripped = LHSStripped; 5314 } else if ((isa<StringLiteral>(RHSStripped) || 5315 isa<ObjCEncodeExpr>(RHSStripped)) && 5316 !LHSStripped->isNullPointerConstant(Context, 5317 Expr::NPC_ValueDependentIsNull)) { 5318 literalString = rex; 5319 literalStringStripped = RHSStripped; 5320 } 5321 5322 if (literalString) { 5323 std::string resultComparison; 5324 switch (Opc) { 5325 case BinaryOperator::LT: resultComparison = ") < 0"; break; 5326 case BinaryOperator::GT: resultComparison = ") > 0"; break; 5327 case BinaryOperator::LE: resultComparison = ") <= 0"; break; 5328 case BinaryOperator::GE: resultComparison = ") >= 0"; break; 5329 case BinaryOperator::EQ: resultComparison = ") == 0"; break; 5330 case BinaryOperator::NE: resultComparison = ") != 0"; break; 5331 default: assert(false && "Invalid comparison operator"); 5332 } 5333 5334 DiagRuntimeBehavior(Loc, 5335 PDiag(diag::warn_stringcompare) 5336 << isa<ObjCEncodeExpr>(literalStringStripped) 5337 << literalString->getSourceRange()); 5338 } 5339 } 5340 5341 // The result of comparisons is 'bool' in C++, 'int' in C. 5342 QualType ResultTy = getLangOptions().CPlusPlus ? Context.BoolTy:Context.IntTy; 5343 5344 if (isRelational) { 5345 if (lType->isRealType() && rType->isRealType()) 5346 return ResultTy; 5347 } else { 5348 // Check for comparisons of floating point operands using != and ==. 5349 if (lType->isFloatingType() && rType->isFloatingType()) 5350 CheckFloatComparison(Loc,lex,rex); 5351 5352 if (lType->isArithmeticType() && rType->isArithmeticType()) 5353 return ResultTy; 5354 } 5355 5356 bool LHSIsNull = lex->isNullPointerConstant(Context, 5357 Expr::NPC_ValueDependentIsNull); 5358 bool RHSIsNull = rex->isNullPointerConstant(Context, 5359 Expr::NPC_ValueDependentIsNull); 5360 5361 // All of the following pointer related warnings are GCC extensions, except 5362 // when handling null pointer constants. One day, we can consider making them 5363 // errors (when -pedantic-errors is enabled). 5364 if (lType->isPointerType() && rType->isPointerType()) { // C99 6.5.8p2 5365 QualType LCanPointeeTy = 5366 Context.getCanonicalType(lType->getAs<PointerType>()->getPointeeType()); 5367 QualType RCanPointeeTy = 5368 Context.getCanonicalType(rType->getAs<PointerType>()->getPointeeType()); 5369 5370 if (getLangOptions().CPlusPlus) { 5371 if (LCanPointeeTy == RCanPointeeTy) 5372 return ResultTy; 5373 if (!isRelational && 5374 (LCanPointeeTy->isVoidType() || RCanPointeeTy->isVoidType())) { 5375 // Valid unless comparison between non-null pointer and function pointer 5376 // This is a gcc extension compatibility comparison. 5377 if ((LCanPointeeTy->isFunctionType() || RCanPointeeTy->isFunctionType()) 5378 && !LHSIsNull && !RHSIsNull) { 5379 Diag(Loc, diag::ext_typecheck_comparison_of_fptr_to_void) 5380 << lType << rType << lex->getSourceRange() << rex->getSourceRange(); 5381 ImpCastExprToType(rex, lType, CastExpr::CK_BitCast); 5382 return ResultTy; 5383 } 5384 } 5385 // C++ [expr.rel]p2: 5386 // [...] Pointer conversions (4.10) and qualification 5387 // conversions (4.4) are performed on pointer operands (or on 5388 // a pointer operand and a null pointer constant) to bring 5389 // them to their composite pointer type. [...] 5390 // 5391 // C++ [expr.eq]p1 uses the same notion for (in)equality 5392 // comparisons of pointers. 5393 bool NonStandardCompositeType = false; 5394 QualType T = FindCompositePointerType(Loc, lex, rex, 5395 isSFINAEContext()? 0 : &NonStandardCompositeType); 5396 if (T.isNull()) { 5397 Diag(Loc, diag::err_typecheck_comparison_of_distinct_pointers) 5398 << lType << rType << lex->getSourceRange() << rex->getSourceRange(); 5399 return QualType(); 5400 } else if (NonStandardCompositeType) { 5401 Diag(Loc, 5402 diag::ext_typecheck_comparison_of_distinct_pointers_nonstandard) 5403 << lType << rType << T 5404 << lex->getSourceRange() << rex->getSourceRange(); 5405 } 5406 5407 ImpCastExprToType(lex, T, CastExpr::CK_BitCast); 5408 ImpCastExprToType(rex, T, CastExpr::CK_BitCast); 5409 return ResultTy; 5410 } 5411 // C99 6.5.9p2 and C99 6.5.8p2 5412 if (Context.typesAreCompatible(LCanPointeeTy.getUnqualifiedType(), 5413 RCanPointeeTy.getUnqualifiedType())) { 5414 // Valid unless a relational comparison of function pointers 5415 if (isRelational && LCanPointeeTy->isFunctionType()) { 5416 Diag(Loc, diag::ext_typecheck_ordered_comparison_of_function_pointers) 5417 << lType << rType << lex->getSourceRange() << rex->getSourceRange(); 5418 } 5419 } else if (!isRelational && 5420 (LCanPointeeTy->isVoidType() || RCanPointeeTy->isVoidType())) { 5421 // Valid unless comparison between non-null pointer and function pointer 5422 if ((LCanPointeeTy->isFunctionType() || RCanPointeeTy->isFunctionType()) 5423 && !LHSIsNull && !RHSIsNull) { 5424 Diag(Loc, diag::ext_typecheck_comparison_of_fptr_to_void) 5425 << lType << rType << lex->getSourceRange() << rex->getSourceRange(); 5426 } 5427 } else { 5428 // Invalid 5429 Diag(Loc, diag::ext_typecheck_comparison_of_distinct_pointers) 5430 << lType << rType << lex->getSourceRange() << rex->getSourceRange(); 5431 } 5432 if (LCanPointeeTy != RCanPointeeTy) 5433 ImpCastExprToType(rex, lType, CastExpr::CK_BitCast); 5434 return ResultTy; 5435 } 5436 5437 if (getLangOptions().CPlusPlus) { 5438 // Comparison of pointers with null pointer constants and equality 5439 // comparisons of member pointers to null pointer constants. 5440 if (RHSIsNull && 5441 (lType->isPointerType() || 5442 (!isRelational && lType->isMemberPointerType()))) { 5443 ImpCastExprToType(rex, lType, CastExpr::CK_NullToMemberPointer); 5444 return ResultTy; 5445 } 5446 if (LHSIsNull && 5447 (rType->isPointerType() || 5448 (!isRelational && rType->isMemberPointerType()))) { 5449 ImpCastExprToType(lex, rType, CastExpr::CK_NullToMemberPointer); 5450 return ResultTy; 5451 } 5452 5453 // Comparison of member pointers. 5454 if (!isRelational && 5455 lType->isMemberPointerType() && rType->isMemberPointerType()) { 5456 // C++ [expr.eq]p2: 5457 // In addition, pointers to members can be compared, or a pointer to 5458 // member and a null pointer constant. Pointer to member conversions 5459 // (4.11) and qualification conversions (4.4) are performed to bring 5460 // them to a common type. If one operand is a null pointer constant, 5461 // the common type is the type of the other operand. Otherwise, the 5462 // common type is a pointer to member type similar (4.4) to the type 5463 // of one of the operands, with a cv-qualification signature (4.4) 5464 // that is the union of the cv-qualification signatures of the operand 5465 // types. 5466 bool NonStandardCompositeType = false; 5467 QualType T = FindCompositePointerType(Loc, lex, rex, 5468 isSFINAEContext()? 0 : &NonStandardCompositeType); 5469 if (T.isNull()) { 5470 Diag(Loc, diag::err_typecheck_comparison_of_distinct_pointers) 5471 << lType << rType << lex->getSourceRange() << rex->getSourceRange(); 5472 return QualType(); 5473 } else if (NonStandardCompositeType) { 5474 Diag(Loc, 5475 diag::ext_typecheck_comparison_of_distinct_pointers_nonstandard) 5476 << lType << rType << T 5477 << lex->getSourceRange() << rex->getSourceRange(); 5478 } 5479 5480 ImpCastExprToType(lex, T, CastExpr::CK_BitCast); 5481 ImpCastExprToType(rex, T, CastExpr::CK_BitCast); 5482 return ResultTy; 5483 } 5484 5485 // Comparison of nullptr_t with itself. 5486 if (lType->isNullPtrType() && rType->isNullPtrType()) 5487 return ResultTy; 5488 } 5489 5490 // Handle block pointer types. 5491 if (!isRelational && lType->isBlockPointerType() && rType->isBlockPointerType()) { 5492 QualType lpointee = lType->getAs<BlockPointerType>()->getPointeeType(); 5493 QualType rpointee = rType->getAs<BlockPointerType>()->getPointeeType(); 5494 5495 if (!LHSIsNull && !RHSIsNull && 5496 !Context.typesAreCompatible(lpointee, rpointee)) { 5497 Diag(Loc, diag::err_typecheck_comparison_of_distinct_blocks) 5498 << lType << rType << lex->getSourceRange() << rex->getSourceRange(); 5499 } 5500 ImpCastExprToType(rex, lType, CastExpr::CK_BitCast); 5501 return ResultTy; 5502 } 5503 // Allow block pointers to be compared with null pointer constants. 5504 if (!isRelational 5505 && ((lType->isBlockPointerType() && rType->isPointerType()) 5506 || (lType->isPointerType() && rType->isBlockPointerType()))) { 5507 if (!LHSIsNull && !RHSIsNull) { 5508 if (!((rType->isPointerType() && rType->getAs<PointerType>() 5509 ->getPointeeType()->isVoidType()) 5510 || (lType->isPointerType() && lType->getAs<PointerType>() 5511 ->getPointeeType()->isVoidType()))) 5512 Diag(Loc, diag::err_typecheck_comparison_of_distinct_blocks) 5513 << lType << rType << lex->getSourceRange() << rex->getSourceRange(); 5514 } 5515 ImpCastExprToType(rex, lType, CastExpr::CK_BitCast); 5516 return ResultTy; 5517 } 5518 5519 if ((lType->isObjCObjectPointerType() || rType->isObjCObjectPointerType())) { 5520 if (lType->isPointerType() || rType->isPointerType()) { 5521 const PointerType *LPT = lType->getAs<PointerType>(); 5522 const PointerType *RPT = rType->getAs<PointerType>(); 5523 bool LPtrToVoid = LPT ? 5524 Context.getCanonicalType(LPT->getPointeeType())->isVoidType() : false; 5525 bool RPtrToVoid = RPT ? 5526 Context.getCanonicalType(RPT->getPointeeType())->isVoidType() : false; 5527 5528 if (!LPtrToVoid && !RPtrToVoid && 5529 !Context.typesAreCompatible(lType, rType)) { 5530 Diag(Loc, diag::ext_typecheck_comparison_of_distinct_pointers) 5531 << lType << rType << lex->getSourceRange() << rex->getSourceRange(); 5532 } 5533 ImpCastExprToType(rex, lType, CastExpr::CK_BitCast); 5534 return ResultTy; 5535 } 5536 if (lType->isObjCObjectPointerType() && rType->isObjCObjectPointerType()) { 5537 if (!Context.areComparableObjCPointerTypes(lType, rType)) 5538 Diag(Loc, diag::ext_typecheck_comparison_of_distinct_pointers) 5539 << lType << rType << lex->getSourceRange() << rex->getSourceRange(); 5540 ImpCastExprToType(rex, lType, CastExpr::CK_BitCast); 5541 return ResultTy; 5542 } 5543 } 5544 if (lType->isAnyPointerType() && rType->isIntegerType()) { 5545 unsigned DiagID = 0; 5546 if (RHSIsNull) { 5547 if (isRelational) 5548 DiagID = diag::ext_typecheck_ordered_comparison_of_pointer_and_zero; 5549 } else if (isRelational) 5550 DiagID = diag::ext_typecheck_ordered_comparison_of_pointer_integer; 5551 else 5552 DiagID = diag::ext_typecheck_comparison_of_pointer_integer; 5553 5554 if (DiagID) { 5555 Diag(Loc, DiagID) 5556 << lType << rType << lex->getSourceRange() << rex->getSourceRange(); 5557 } 5558 ImpCastExprToType(rex, lType, CastExpr::CK_IntegralToPointer); 5559 return ResultTy; 5560 } 5561 if (lType->isIntegerType() && rType->isAnyPointerType()) { 5562 unsigned DiagID = 0; 5563 if (LHSIsNull) { 5564 if (isRelational) 5565 DiagID = diag::ext_typecheck_ordered_comparison_of_pointer_and_zero; 5566 } else if (isRelational) 5567 DiagID = diag::ext_typecheck_ordered_comparison_of_pointer_integer; 5568 else 5569 DiagID = diag::ext_typecheck_comparison_of_pointer_integer; 5570 5571 if (DiagID) { 5572 Diag(Loc, DiagID) 5573 << lType << rType << lex->getSourceRange() << rex->getSourceRange(); 5574 } 5575 ImpCastExprToType(lex, rType, CastExpr::CK_IntegralToPointer); 5576 return ResultTy; 5577 } 5578 // Handle block pointers. 5579 if (!isRelational && RHSIsNull 5580 && lType->isBlockPointerType() && rType->isIntegerType()) { 5581 ImpCastExprToType(rex, lType, CastExpr::CK_IntegralToPointer); 5582 return ResultTy; 5583 } 5584 if (!isRelational && LHSIsNull 5585 && lType->isIntegerType() && rType->isBlockPointerType()) { 5586 ImpCastExprToType(lex, rType, CastExpr::CK_IntegralToPointer); 5587 return ResultTy; 5588 } 5589 return InvalidOperands(Loc, lex, rex); 5590} 5591 5592/// CheckVectorCompareOperands - vector comparisons are a clang extension that 5593/// operates on extended vector types. Instead of producing an IntTy result, 5594/// like a scalar comparison, a vector comparison produces a vector of integer 5595/// types. 5596QualType Sema::CheckVectorCompareOperands(Expr *&lex, Expr *&rex, 5597 SourceLocation Loc, 5598 bool isRelational) { 5599 // Check to make sure we're operating on vectors of the same type and width, 5600 // Allowing one side to be a scalar of element type. 5601 QualType vType = CheckVectorOperands(Loc, lex, rex); 5602 if (vType.isNull()) 5603 return vType; 5604 5605 QualType lType = lex->getType(); 5606 QualType rType = rex->getType(); 5607 5608 // For non-floating point types, check for self-comparisons of the form 5609 // x == x, x != x, x < x, etc. These always evaluate to a constant, and 5610 // often indicate logic errors in the program. 5611 if (!lType->isFloatingType()) { 5612 if (DeclRefExpr* DRL = dyn_cast<DeclRefExpr>(lex->IgnoreParens())) 5613 if (DeclRefExpr* DRR = dyn_cast<DeclRefExpr>(rex->IgnoreParens())) 5614 if (DRL->getDecl() == DRR->getDecl()) 5615 DiagRuntimeBehavior(Loc, PDiag(diag::warn_selfcomparison)); 5616 } 5617 5618 // Check for comparisons of floating point operands using != and ==. 5619 if (!isRelational && lType->isFloatingType()) { 5620 assert (rType->isFloatingType()); 5621 CheckFloatComparison(Loc,lex,rex); 5622 } 5623 5624 // Return the type for the comparison, which is the same as vector type for 5625 // integer vectors, or an integer type of identical size and number of 5626 // elements for floating point vectors. 5627 if (lType->isIntegerType()) 5628 return lType; 5629 5630 const VectorType *VTy = lType->getAs<VectorType>(); 5631 unsigned TypeSize = Context.getTypeSize(VTy->getElementType()); 5632 if (TypeSize == Context.getTypeSize(Context.IntTy)) 5633 return Context.getExtVectorType(Context.IntTy, VTy->getNumElements()); 5634 if (TypeSize == Context.getTypeSize(Context.LongTy)) 5635 return Context.getExtVectorType(Context.LongTy, VTy->getNumElements()); 5636 5637 assert(TypeSize == Context.getTypeSize(Context.LongLongTy) && 5638 "Unhandled vector element size in vector compare"); 5639 return Context.getExtVectorType(Context.LongLongTy, VTy->getNumElements()); 5640} 5641 5642inline QualType Sema::CheckBitwiseOperands( 5643 Expr *&lex, Expr *&rex, SourceLocation Loc, bool isCompAssign) { 5644 if (lex->getType()->isVectorType() || rex->getType()->isVectorType()) 5645 return CheckVectorOperands(Loc, lex, rex); 5646 5647 QualType compType = UsualArithmeticConversions(lex, rex, isCompAssign); 5648 5649 if (lex->getType()->isIntegerType() && rex->getType()->isIntegerType()) 5650 return compType; 5651 return InvalidOperands(Loc, lex, rex); 5652} 5653 5654inline QualType Sema::CheckLogicalOperands( // C99 6.5.[13,14] 5655 Expr *&lex, Expr *&rex, SourceLocation Loc) { 5656 if (!Context.getLangOptions().CPlusPlus) { 5657 UsualUnaryConversions(lex); 5658 UsualUnaryConversions(rex); 5659 5660 if (!lex->getType()->isScalarType() || !rex->getType()->isScalarType()) 5661 return InvalidOperands(Loc, lex, rex); 5662 5663 return Context.IntTy; 5664 } 5665 5666 // The following is safe because we only use this method for 5667 // non-overloadable operands. 5668 5669 // C++ [expr.log.and]p1 5670 // C++ [expr.log.or]p1 5671 // The operands are both contextually converted to type bool. 5672 if (PerformContextuallyConvertToBool(lex) || 5673 PerformContextuallyConvertToBool(rex)) 5674 return InvalidOperands(Loc, lex, rex); 5675 5676 // C++ [expr.log.and]p2 5677 // C++ [expr.log.or]p2 5678 // The result is a bool. 5679 return Context.BoolTy; 5680} 5681 5682/// IsReadonlyProperty - Verify that otherwise a valid l-value expression 5683/// is a read-only property; return true if so. A readonly property expression 5684/// depends on various declarations and thus must be treated specially. 5685/// 5686static bool IsReadonlyProperty(Expr *E, Sema &S) { 5687 if (E->getStmtClass() == Expr::ObjCPropertyRefExprClass) { 5688 const ObjCPropertyRefExpr* PropExpr = cast<ObjCPropertyRefExpr>(E); 5689 if (ObjCPropertyDecl *PDecl = PropExpr->getProperty()) { 5690 QualType BaseType = PropExpr->getBase()->getType(); 5691 if (const ObjCObjectPointerType *OPT = 5692 BaseType->getAsObjCInterfacePointerType()) 5693 if (ObjCInterfaceDecl *IFace = OPT->getInterfaceDecl()) 5694 if (S.isPropertyReadonly(PDecl, IFace)) 5695 return true; 5696 } 5697 } 5698 return false; 5699} 5700 5701/// CheckForModifiableLvalue - Verify that E is a modifiable lvalue. If not, 5702/// emit an error and return true. If so, return false. 5703static bool CheckForModifiableLvalue(Expr *E, SourceLocation Loc, Sema &S) { 5704 SourceLocation OrigLoc = Loc; 5705 Expr::isModifiableLvalueResult IsLV = E->isModifiableLvalue(S.Context, 5706 &Loc); 5707 if (IsLV == Expr::MLV_Valid && IsReadonlyProperty(E, S)) 5708 IsLV = Expr::MLV_ReadonlyProperty; 5709 if (IsLV == Expr::MLV_Valid) 5710 return false; 5711 5712 unsigned Diag = 0; 5713 bool NeedType = false; 5714 switch (IsLV) { // C99 6.5.16p2 5715 case Expr::MLV_ConstQualified: Diag = diag::err_typecheck_assign_const; break; 5716 case Expr::MLV_ArrayType: 5717 Diag = diag::err_typecheck_array_not_modifiable_lvalue; 5718 NeedType = true; 5719 break; 5720 case Expr::MLV_NotObjectType: 5721 Diag = diag::err_typecheck_non_object_not_modifiable_lvalue; 5722 NeedType = true; 5723 break; 5724 case Expr::MLV_LValueCast: 5725 Diag = diag::err_typecheck_lvalue_casts_not_supported; 5726 break; 5727 case Expr::MLV_Valid: 5728 llvm_unreachable("did not take early return for MLV_Valid"); 5729 case Expr::MLV_InvalidExpression: 5730 case Expr::MLV_MemberFunction: 5731 case Expr::MLV_ClassTemporary: 5732 Diag = diag::err_typecheck_expression_not_modifiable_lvalue; 5733 break; 5734 case Expr::MLV_IncompleteType: 5735 case Expr::MLV_IncompleteVoidType: 5736 return S.RequireCompleteType(Loc, E->getType(), 5737 S.PDiag(diag::err_typecheck_incomplete_type_not_modifiable_lvalue) 5738 << E->getSourceRange()); 5739 case Expr::MLV_DuplicateVectorComponents: 5740 Diag = diag::err_typecheck_duplicate_vector_components_not_mlvalue; 5741 break; 5742 case Expr::MLV_NotBlockQualified: 5743 Diag = diag::err_block_decl_ref_not_modifiable_lvalue; 5744 break; 5745 case Expr::MLV_ReadonlyProperty: 5746 Diag = diag::error_readonly_property_assignment; 5747 break; 5748 case Expr::MLV_NoSetterProperty: 5749 Diag = diag::error_nosetter_property_assignment; 5750 break; 5751 case Expr::MLV_SubObjCPropertySetting: 5752 Diag = diag::error_no_subobject_property_setting; 5753 break; 5754 } 5755 5756 SourceRange Assign; 5757 if (Loc != OrigLoc) 5758 Assign = SourceRange(OrigLoc, OrigLoc); 5759 if (NeedType) 5760 S.Diag(Loc, Diag) << E->getType() << E->getSourceRange() << Assign; 5761 else 5762 S.Diag(Loc, Diag) << E->getSourceRange() << Assign; 5763 return true; 5764} 5765 5766 5767 5768// C99 6.5.16.1 5769QualType Sema::CheckAssignmentOperands(Expr *LHS, Expr *&RHS, 5770 SourceLocation Loc, 5771 QualType CompoundType) { 5772 // Verify that LHS is a modifiable lvalue, and emit error if not. 5773 if (CheckForModifiableLvalue(LHS, Loc, *this)) 5774 return QualType(); 5775 5776 QualType LHSType = LHS->getType(); 5777 QualType RHSType = CompoundType.isNull() ? RHS->getType() : CompoundType; 5778 5779 AssignConvertType ConvTy; 5780 if (CompoundType.isNull()) { 5781 // Simple assignment "x = y". 5782 ConvTy = CheckSingleAssignmentConstraints(LHSType, RHS); 5783 // Special case of NSObject attributes on c-style pointer types. 5784 if (ConvTy == IncompatiblePointer && 5785 ((Context.isObjCNSObjectType(LHSType) && 5786 RHSType->isObjCObjectPointerType()) || 5787 (Context.isObjCNSObjectType(RHSType) && 5788 LHSType->isObjCObjectPointerType()))) 5789 ConvTy = Compatible; 5790 5791 // If the RHS is a unary plus or minus, check to see if they = and + are 5792 // right next to each other. If so, the user may have typo'd "x =+ 4" 5793 // instead of "x += 4". 5794 Expr *RHSCheck = RHS; 5795 if (ImplicitCastExpr *ICE = dyn_cast<ImplicitCastExpr>(RHSCheck)) 5796 RHSCheck = ICE->getSubExpr(); 5797 if (UnaryOperator *UO = dyn_cast<UnaryOperator>(RHSCheck)) { 5798 if ((UO->getOpcode() == UnaryOperator::Plus || 5799 UO->getOpcode() == UnaryOperator::Minus) && 5800 Loc.isFileID() && UO->getOperatorLoc().isFileID() && 5801 // Only if the two operators are exactly adjacent. 5802 Loc.getFileLocWithOffset(1) == UO->getOperatorLoc() && 5803 // And there is a space or other character before the subexpr of the 5804 // unary +/-. We don't want to warn on "x=-1". 5805 Loc.getFileLocWithOffset(2) != UO->getSubExpr()->getLocStart() && 5806 UO->getSubExpr()->getLocStart().isFileID()) { 5807 Diag(Loc, diag::warn_not_compound_assign) 5808 << (UO->getOpcode() == UnaryOperator::Plus ? "+" : "-") 5809 << SourceRange(UO->getOperatorLoc(), UO->getOperatorLoc()); 5810 } 5811 } 5812 } else { 5813 // Compound assignment "x += y" 5814 ConvTy = CheckAssignmentConstraints(LHSType, RHSType); 5815 } 5816 5817 if (DiagnoseAssignmentResult(ConvTy, Loc, LHSType, RHSType, 5818 RHS, AA_Assigning)) 5819 return QualType(); 5820 5821 // C99 6.5.16p3: The type of an assignment expression is the type of the 5822 // left operand unless the left operand has qualified type, in which case 5823 // it is the unqualified version of the type of the left operand. 5824 // C99 6.5.16.1p2: In simple assignment, the value of the right operand 5825 // is converted to the type of the assignment expression (above). 5826 // C++ 5.17p1: the type of the assignment expression is that of its left 5827 // operand. 5828 return LHSType.getUnqualifiedType(); 5829} 5830 5831// C99 6.5.17 5832QualType Sema::CheckCommaOperands(Expr *LHS, Expr *&RHS, SourceLocation Loc) { 5833 // Comma performs lvalue conversion (C99 6.3.2.1), but not unary conversions. 5834 // C++ does not perform this conversion (C++ [expr.comma]p1). 5835 if (!getLangOptions().CPlusPlus) 5836 DefaultFunctionArrayLvalueConversion(RHS); 5837 5838 // FIXME: Check that RHS type is complete in C mode (it's legal for it to be 5839 // incomplete in C++). 5840 5841 return RHS->getType(); 5842} 5843 5844/// CheckIncrementDecrementOperand - unlike most "Check" methods, this routine 5845/// doesn't need to call UsualUnaryConversions or UsualArithmeticConversions. 5846QualType Sema::CheckIncrementDecrementOperand(Expr *Op, SourceLocation OpLoc, 5847 bool isInc, bool isPrefix) { 5848 if (Op->isTypeDependent()) 5849 return Context.DependentTy; 5850 5851 QualType ResType = Op->getType(); 5852 assert(!ResType.isNull() && "no type for increment/decrement expression"); 5853 5854 if (getLangOptions().CPlusPlus && ResType->isBooleanType()) { 5855 // Decrement of bool is not allowed. 5856 if (!isInc) { 5857 Diag(OpLoc, diag::err_decrement_bool) << Op->getSourceRange(); 5858 return QualType(); 5859 } 5860 // Increment of bool sets it to true, but is deprecated. 5861 Diag(OpLoc, diag::warn_increment_bool) << Op->getSourceRange(); 5862 } else if (ResType->isRealType()) { 5863 // OK! 5864 } else if (ResType->isAnyPointerType()) { 5865 QualType PointeeTy = ResType->getPointeeType(); 5866 5867 // C99 6.5.2.4p2, 6.5.6p2 5868 if (PointeeTy->isVoidType()) { 5869 if (getLangOptions().CPlusPlus) { 5870 Diag(OpLoc, diag::err_typecheck_pointer_arith_void_type) 5871 << Op->getSourceRange(); 5872 return QualType(); 5873 } 5874 5875 // Pointer to void is a GNU extension in C. 5876 Diag(OpLoc, diag::ext_gnu_void_ptr) << Op->getSourceRange(); 5877 } else if (PointeeTy->isFunctionType()) { 5878 if (getLangOptions().CPlusPlus) { 5879 Diag(OpLoc, diag::err_typecheck_pointer_arith_function_type) 5880 << Op->getType() << Op->getSourceRange(); 5881 return QualType(); 5882 } 5883 5884 Diag(OpLoc, diag::ext_gnu_ptr_func_arith) 5885 << ResType << Op->getSourceRange(); 5886 } else if (RequireCompleteType(OpLoc, PointeeTy, 5887 PDiag(diag::err_typecheck_arithmetic_incomplete_type) 5888 << Op->getSourceRange() 5889 << ResType)) 5890 return QualType(); 5891 // Diagnose bad cases where we step over interface counts. 5892 else if (PointeeTy->isObjCObjectType() && LangOpts.ObjCNonFragileABI) { 5893 Diag(OpLoc, diag::err_arithmetic_nonfragile_interface) 5894 << PointeeTy << Op->getSourceRange(); 5895 return QualType(); 5896 } 5897 } else if (ResType->isAnyComplexType()) { 5898 // C99 does not support ++/-- on complex types, we allow as an extension. 5899 Diag(OpLoc, diag::ext_integer_increment_complex) 5900 << ResType << Op->getSourceRange(); 5901 } else { 5902 Diag(OpLoc, diag::err_typecheck_illegal_increment_decrement) 5903 << ResType << int(isInc) << Op->getSourceRange(); 5904 return QualType(); 5905 } 5906 // At this point, we know we have a real, complex or pointer type. 5907 // Now make sure the operand is a modifiable lvalue. 5908 if (CheckForModifiableLvalue(Op, OpLoc, *this)) 5909 return QualType(); 5910 // In C++, a prefix increment is the same type as the operand. Otherwise 5911 // (in C or with postfix), the increment is the unqualified type of the 5912 // operand. 5913 return isPrefix && getLangOptions().CPlusPlus 5914 ? ResType : ResType.getUnqualifiedType(); 5915} 5916 5917/// getPrimaryDecl - Helper function for CheckAddressOfOperand(). 5918/// This routine allows us to typecheck complex/recursive expressions 5919/// where the declaration is needed for type checking. We only need to 5920/// handle cases when the expression references a function designator 5921/// or is an lvalue. Here are some examples: 5922/// - &(x) => x 5923/// - &*****f => f for f a function designator. 5924/// - &s.xx => s 5925/// - &s.zz[1].yy -> s, if zz is an array 5926/// - *(x + 1) -> x, if x is an array 5927/// - &"123"[2] -> 0 5928/// - & __real__ x -> x 5929static NamedDecl *getPrimaryDecl(Expr *E) { 5930 switch (E->getStmtClass()) { 5931 case Stmt::DeclRefExprClass: 5932 return cast<DeclRefExpr>(E)->getDecl(); 5933 case Stmt::MemberExprClass: 5934 // If this is an arrow operator, the address is an offset from 5935 // the base's value, so the object the base refers to is 5936 // irrelevant. 5937 if (cast<MemberExpr>(E)->isArrow()) 5938 return 0; 5939 // Otherwise, the expression refers to a part of the base 5940 return getPrimaryDecl(cast<MemberExpr>(E)->getBase()); 5941 case Stmt::ArraySubscriptExprClass: { 5942 // FIXME: This code shouldn't be necessary! We should catch the implicit 5943 // promotion of register arrays earlier. 5944 Expr* Base = cast<ArraySubscriptExpr>(E)->getBase(); 5945 if (ImplicitCastExpr* ICE = dyn_cast<ImplicitCastExpr>(Base)) { 5946 if (ICE->getSubExpr()->getType()->isArrayType()) 5947 return getPrimaryDecl(ICE->getSubExpr()); 5948 } 5949 return 0; 5950 } 5951 case Stmt::UnaryOperatorClass: { 5952 UnaryOperator *UO = cast<UnaryOperator>(E); 5953 5954 switch(UO->getOpcode()) { 5955 case UnaryOperator::Real: 5956 case UnaryOperator::Imag: 5957 case UnaryOperator::Extension: 5958 return getPrimaryDecl(UO->getSubExpr()); 5959 default: 5960 return 0; 5961 } 5962 } 5963 case Stmt::ParenExprClass: 5964 return getPrimaryDecl(cast<ParenExpr>(E)->getSubExpr()); 5965 case Stmt::ImplicitCastExprClass: 5966 // If the result of an implicit cast is an l-value, we care about 5967 // the sub-expression; otherwise, the result here doesn't matter. 5968 return getPrimaryDecl(cast<ImplicitCastExpr>(E)->getSubExpr()); 5969 default: 5970 return 0; 5971 } 5972} 5973 5974/// CheckAddressOfOperand - The operand of & must be either a function 5975/// designator or an lvalue designating an object. If it is an lvalue, the 5976/// object cannot be declared with storage class register or be a bit field. 5977/// Note: The usual conversions are *not* applied to the operand of the & 5978/// operator (C99 6.3.2.1p[2-4]), and its result is never an lvalue. 5979/// In C++, the operand might be an overloaded function name, in which case 5980/// we allow the '&' but retain the overloaded-function type. 5981QualType Sema::CheckAddressOfOperand(Expr *op, SourceLocation OpLoc) { 5982 // Make sure to ignore parentheses in subsequent checks 5983 op = op->IgnoreParens(); 5984 5985 if (op->isTypeDependent()) 5986 return Context.DependentTy; 5987 5988 if (getLangOptions().C99) { 5989 // Implement C99-only parts of addressof rules. 5990 if (UnaryOperator* uOp = dyn_cast<UnaryOperator>(op)) { 5991 if (uOp->getOpcode() == UnaryOperator::Deref) 5992 // Per C99 6.5.3.2, the address of a deref always returns a valid result 5993 // (assuming the deref expression is valid). 5994 return uOp->getSubExpr()->getType(); 5995 } 5996 // Technically, there should be a check for array subscript 5997 // expressions here, but the result of one is always an lvalue anyway. 5998 } 5999 NamedDecl *dcl = getPrimaryDecl(op); 6000 Expr::isLvalueResult lval = op->isLvalue(Context); 6001 6002 MemberExpr *ME = dyn_cast<MemberExpr>(op); 6003 if (lval == Expr::LV_MemberFunction && ME && 6004 isa<CXXMethodDecl>(ME->getMemberDecl())) { 6005 ValueDecl *dcl = cast<MemberExpr>(op)->getMemberDecl(); 6006 // &f where f is a member of the current object, or &o.f, or &p->f 6007 // All these are not allowed, and we need to catch them before the dcl 6008 // branch of the if, below. 6009 Diag(OpLoc, diag::err_unqualified_pointer_member_function) 6010 << dcl; 6011 // FIXME: Improve this diagnostic and provide a fixit. 6012 6013 // Now recover by acting as if the function had been accessed qualified. 6014 return Context.getMemberPointerType(op->getType(), 6015 Context.getTypeDeclType(cast<RecordDecl>(dcl->getDeclContext())) 6016 .getTypePtr()); 6017 } else if (lval == Expr::LV_ClassTemporary) { 6018 Diag(OpLoc, isSFINAEContext()? diag::err_typecheck_addrof_class_temporary 6019 : diag::ext_typecheck_addrof_class_temporary) 6020 << op->getType() << op->getSourceRange(); 6021 if (isSFINAEContext()) 6022 return QualType(); 6023 } else if (lval != Expr::LV_Valid && lval != Expr::LV_IncompleteVoidType) { 6024 // C99 6.5.3.2p1 6025 // The operand must be either an l-value or a function designator 6026 if (!op->getType()->isFunctionType()) { 6027 // FIXME: emit more specific diag... 6028 Diag(OpLoc, diag::err_typecheck_invalid_lvalue_addrof) 6029 << op->getSourceRange(); 6030 return QualType(); 6031 } 6032 } else if (op->getBitField()) { // C99 6.5.3.2p1 6033 // The operand cannot be a bit-field 6034 Diag(OpLoc, diag::err_typecheck_address_of) 6035 << "bit-field" << op->getSourceRange(); 6036 return QualType(); 6037 } else if (op->refersToVectorElement()) { 6038 // The operand cannot be an element of a vector 6039 Diag(OpLoc, diag::err_typecheck_address_of) 6040 << "vector element" << op->getSourceRange(); 6041 return QualType(); 6042 } else if (isa<ObjCPropertyRefExpr>(op)) { 6043 // cannot take address of a property expression. 6044 Diag(OpLoc, diag::err_typecheck_address_of) 6045 << "property expression" << op->getSourceRange(); 6046 return QualType(); 6047 } else if (ConditionalOperator *CO = dyn_cast<ConditionalOperator>(op)) { 6048 // FIXME: Can LHS ever be null here? 6049 if (!CheckAddressOfOperand(CO->getTrueExpr(), OpLoc).isNull()) 6050 return CheckAddressOfOperand(CO->getFalseExpr(), OpLoc); 6051 } else if (isa<UnresolvedLookupExpr>(op)) { 6052 return Context.OverloadTy; 6053 } else if (dcl) { // C99 6.5.3.2p1 6054 // We have an lvalue with a decl. Make sure the decl is not declared 6055 // with the register storage-class specifier. 6056 if (const VarDecl *vd = dyn_cast<VarDecl>(dcl)) { 6057 if (vd->getStorageClass() == VarDecl::Register) { 6058 Diag(OpLoc, diag::err_typecheck_address_of) 6059 << "register variable" << op->getSourceRange(); 6060 return QualType(); 6061 } 6062 } else if (isa<FunctionTemplateDecl>(dcl)) { 6063 return Context.OverloadTy; 6064 } else if (FieldDecl *FD = dyn_cast<FieldDecl>(dcl)) { 6065 // Okay: we can take the address of a field. 6066 // Could be a pointer to member, though, if there is an explicit 6067 // scope qualifier for the class. 6068 if (isa<DeclRefExpr>(op) && cast<DeclRefExpr>(op)->getQualifier()) { 6069 DeclContext *Ctx = dcl->getDeclContext(); 6070 if (Ctx && Ctx->isRecord()) { 6071 if (FD->getType()->isReferenceType()) { 6072 Diag(OpLoc, 6073 diag::err_cannot_form_pointer_to_member_of_reference_type) 6074 << FD->getDeclName() << FD->getType(); 6075 return QualType(); 6076 } 6077 6078 return Context.getMemberPointerType(op->getType(), 6079 Context.getTypeDeclType(cast<RecordDecl>(Ctx)).getTypePtr()); 6080 } 6081 } 6082 } else if (CXXMethodDecl *MD = dyn_cast<CXXMethodDecl>(dcl)) { 6083 // Okay: we can take the address of a function. 6084 // As above. 6085 if (isa<DeclRefExpr>(op) && cast<DeclRefExpr>(op)->getQualifier() && 6086 MD->isInstance()) 6087 return Context.getMemberPointerType(op->getType(), 6088 Context.getTypeDeclType(MD->getParent()).getTypePtr()); 6089 } else if (!isa<FunctionDecl>(dcl)) 6090 assert(0 && "Unknown/unexpected decl type"); 6091 } 6092 6093 if (lval == Expr::LV_IncompleteVoidType) { 6094 // Taking the address of a void variable is technically illegal, but we 6095 // allow it in cases which are otherwise valid. 6096 // Example: "extern void x; void* y = &x;". 6097 Diag(OpLoc, diag::ext_typecheck_addrof_void) << op->getSourceRange(); 6098 } 6099 6100 // If the operand has type "type", the result has type "pointer to type". 6101 return Context.getPointerType(op->getType()); 6102} 6103 6104QualType Sema::CheckIndirectionOperand(Expr *Op, SourceLocation OpLoc) { 6105 if (Op->isTypeDependent()) 6106 return Context.DependentTy; 6107 6108 UsualUnaryConversions(Op); 6109 QualType Ty = Op->getType(); 6110 6111 // Note that per both C89 and C99, this is always legal, even if ptype is an 6112 // incomplete type or void. It would be possible to warn about dereferencing 6113 // a void pointer, but it's completely well-defined, and such a warning is 6114 // unlikely to catch any mistakes. 6115 if (const PointerType *PT = Ty->getAs<PointerType>()) 6116 return PT->getPointeeType(); 6117 6118 if (const ObjCObjectPointerType *OPT = Ty->getAs<ObjCObjectPointerType>()) 6119 return OPT->getPointeeType(); 6120 6121 Diag(OpLoc, diag::err_typecheck_indirection_requires_pointer) 6122 << Ty << Op->getSourceRange(); 6123 return QualType(); 6124} 6125 6126static inline BinaryOperator::Opcode ConvertTokenKindToBinaryOpcode( 6127 tok::TokenKind Kind) { 6128 BinaryOperator::Opcode Opc; 6129 switch (Kind) { 6130 default: assert(0 && "Unknown binop!"); 6131 case tok::periodstar: Opc = BinaryOperator::PtrMemD; break; 6132 case tok::arrowstar: Opc = BinaryOperator::PtrMemI; break; 6133 case tok::star: Opc = BinaryOperator::Mul; break; 6134 case tok::slash: Opc = BinaryOperator::Div; break; 6135 case tok::percent: Opc = BinaryOperator::Rem; break; 6136 case tok::plus: Opc = BinaryOperator::Add; break; 6137 case tok::minus: Opc = BinaryOperator::Sub; break; 6138 case tok::lessless: Opc = BinaryOperator::Shl; break; 6139 case tok::greatergreater: Opc = BinaryOperator::Shr; break; 6140 case tok::lessequal: Opc = BinaryOperator::LE; break; 6141 case tok::less: Opc = BinaryOperator::LT; break; 6142 case tok::greaterequal: Opc = BinaryOperator::GE; break; 6143 case tok::greater: Opc = BinaryOperator::GT; break; 6144 case tok::exclaimequal: Opc = BinaryOperator::NE; break; 6145 case tok::equalequal: Opc = BinaryOperator::EQ; break; 6146 case tok::amp: Opc = BinaryOperator::And; break; 6147 case tok::caret: Opc = BinaryOperator::Xor; break; 6148 case tok::pipe: Opc = BinaryOperator::Or; break; 6149 case tok::ampamp: Opc = BinaryOperator::LAnd; break; 6150 case tok::pipepipe: Opc = BinaryOperator::LOr; break; 6151 case tok::equal: Opc = BinaryOperator::Assign; break; 6152 case tok::starequal: Opc = BinaryOperator::MulAssign; break; 6153 case tok::slashequal: Opc = BinaryOperator::DivAssign; break; 6154 case tok::percentequal: Opc = BinaryOperator::RemAssign; break; 6155 case tok::plusequal: Opc = BinaryOperator::AddAssign; break; 6156 case tok::minusequal: Opc = BinaryOperator::SubAssign; break; 6157 case tok::lesslessequal: Opc = BinaryOperator::ShlAssign; break; 6158 case tok::greatergreaterequal: Opc = BinaryOperator::ShrAssign; break; 6159 case tok::ampequal: Opc = BinaryOperator::AndAssign; break; 6160 case tok::caretequal: Opc = BinaryOperator::XorAssign; break; 6161 case tok::pipeequal: Opc = BinaryOperator::OrAssign; break; 6162 case tok::comma: Opc = BinaryOperator::Comma; break; 6163 } 6164 return Opc; 6165} 6166 6167static inline UnaryOperator::Opcode ConvertTokenKindToUnaryOpcode( 6168 tok::TokenKind Kind) { 6169 UnaryOperator::Opcode Opc; 6170 switch (Kind) { 6171 default: assert(0 && "Unknown unary op!"); 6172 case tok::plusplus: Opc = UnaryOperator::PreInc; break; 6173 case tok::minusminus: Opc = UnaryOperator::PreDec; break; 6174 case tok::amp: Opc = UnaryOperator::AddrOf; break; 6175 case tok::star: Opc = UnaryOperator::Deref; break; 6176 case tok::plus: Opc = UnaryOperator::Plus; break; 6177 case tok::minus: Opc = UnaryOperator::Minus; break; 6178 case tok::tilde: Opc = UnaryOperator::Not; break; 6179 case tok::exclaim: Opc = UnaryOperator::LNot; break; 6180 case tok::kw___real: Opc = UnaryOperator::Real; break; 6181 case tok::kw___imag: Opc = UnaryOperator::Imag; break; 6182 case tok::kw___extension__: Opc = UnaryOperator::Extension; break; 6183 } 6184 return Opc; 6185} 6186 6187/// CreateBuiltinBinOp - Creates a new built-in binary operation with 6188/// operator @p Opc at location @c TokLoc. This routine only supports 6189/// built-in operations; ActOnBinOp handles overloaded operators. 6190Action::OwningExprResult Sema::CreateBuiltinBinOp(SourceLocation OpLoc, 6191 unsigned Op, 6192 Expr *lhs, Expr *rhs) { 6193 QualType ResultTy; // Result type of the binary operator. 6194 BinaryOperator::Opcode Opc = (BinaryOperator::Opcode)Op; 6195 // The following two variables are used for compound assignment operators 6196 QualType CompLHSTy; // Type of LHS after promotions for computation 6197 QualType CompResultTy; // Type of computation result 6198 6199 switch (Opc) { 6200 case BinaryOperator::Assign: 6201 ResultTy = CheckAssignmentOperands(lhs, rhs, OpLoc, QualType()); 6202 break; 6203 case BinaryOperator::PtrMemD: 6204 case BinaryOperator::PtrMemI: 6205 ResultTy = CheckPointerToMemberOperands(lhs, rhs, OpLoc, 6206 Opc == BinaryOperator::PtrMemI); 6207 break; 6208 case BinaryOperator::Mul: 6209 case BinaryOperator::Div: 6210 ResultTy = CheckMultiplyDivideOperands(lhs, rhs, OpLoc, false, 6211 Opc == BinaryOperator::Div); 6212 break; 6213 case BinaryOperator::Rem: 6214 ResultTy = CheckRemainderOperands(lhs, rhs, OpLoc); 6215 break; 6216 case BinaryOperator::Add: 6217 ResultTy = CheckAdditionOperands(lhs, rhs, OpLoc); 6218 break; 6219 case BinaryOperator::Sub: 6220 ResultTy = CheckSubtractionOperands(lhs, rhs, OpLoc); 6221 break; 6222 case BinaryOperator::Shl: 6223 case BinaryOperator::Shr: 6224 ResultTy = CheckShiftOperands(lhs, rhs, OpLoc); 6225 break; 6226 case BinaryOperator::LE: 6227 case BinaryOperator::LT: 6228 case BinaryOperator::GE: 6229 case BinaryOperator::GT: 6230 ResultTy = CheckCompareOperands(lhs, rhs, OpLoc, Opc, true); 6231 break; 6232 case BinaryOperator::EQ: 6233 case BinaryOperator::NE: 6234 ResultTy = CheckCompareOperands(lhs, rhs, OpLoc, Opc, false); 6235 break; 6236 case BinaryOperator::And: 6237 case BinaryOperator::Xor: 6238 case BinaryOperator::Or: 6239 ResultTy = CheckBitwiseOperands(lhs, rhs, OpLoc); 6240 break; 6241 case BinaryOperator::LAnd: 6242 case BinaryOperator::LOr: 6243 ResultTy = CheckLogicalOperands(lhs, rhs, OpLoc); 6244 break; 6245 case BinaryOperator::MulAssign: 6246 case BinaryOperator::DivAssign: 6247 CompResultTy = CheckMultiplyDivideOperands(lhs, rhs, OpLoc, true, 6248 Opc == BinaryOperator::DivAssign); 6249 CompLHSTy = CompResultTy; 6250 if (!CompResultTy.isNull()) 6251 ResultTy = CheckAssignmentOperands(lhs, rhs, OpLoc, CompResultTy); 6252 break; 6253 case BinaryOperator::RemAssign: 6254 CompResultTy = CheckRemainderOperands(lhs, rhs, OpLoc, true); 6255 CompLHSTy = CompResultTy; 6256 if (!CompResultTy.isNull()) 6257 ResultTy = CheckAssignmentOperands(lhs, rhs, OpLoc, CompResultTy); 6258 break; 6259 case BinaryOperator::AddAssign: 6260 CompResultTy = CheckAdditionOperands(lhs, rhs, OpLoc, &CompLHSTy); 6261 if (!CompResultTy.isNull()) 6262 ResultTy = CheckAssignmentOperands(lhs, rhs, OpLoc, CompResultTy); 6263 break; 6264 case BinaryOperator::SubAssign: 6265 CompResultTy = CheckSubtractionOperands(lhs, rhs, OpLoc, &CompLHSTy); 6266 if (!CompResultTy.isNull()) 6267 ResultTy = CheckAssignmentOperands(lhs, rhs, OpLoc, CompResultTy); 6268 break; 6269 case BinaryOperator::ShlAssign: 6270 case BinaryOperator::ShrAssign: 6271 CompResultTy = CheckShiftOperands(lhs, rhs, OpLoc, true); 6272 CompLHSTy = CompResultTy; 6273 if (!CompResultTy.isNull()) 6274 ResultTy = CheckAssignmentOperands(lhs, rhs, OpLoc, CompResultTy); 6275 break; 6276 case BinaryOperator::AndAssign: 6277 case BinaryOperator::XorAssign: 6278 case BinaryOperator::OrAssign: 6279 CompResultTy = CheckBitwiseOperands(lhs, rhs, OpLoc, true); 6280 CompLHSTy = CompResultTy; 6281 if (!CompResultTy.isNull()) 6282 ResultTy = CheckAssignmentOperands(lhs, rhs, OpLoc, CompResultTy); 6283 break; 6284 case BinaryOperator::Comma: 6285 ResultTy = CheckCommaOperands(lhs, rhs, OpLoc); 6286 break; 6287 } 6288 if (ResultTy.isNull()) 6289 return ExprError(); 6290 if (CompResultTy.isNull()) 6291 return Owned(new (Context) BinaryOperator(lhs, rhs, Opc, ResultTy, OpLoc)); 6292 else 6293 return Owned(new (Context) CompoundAssignOperator(lhs, rhs, Opc, ResultTy, 6294 CompLHSTy, CompResultTy, 6295 OpLoc)); 6296} 6297 6298/// SuggestParentheses - Emit a diagnostic together with a fixit hint that wraps 6299/// ParenRange in parentheses. 6300static void SuggestParentheses(Sema &Self, SourceLocation Loc, 6301 const PartialDiagnostic &PD, 6302 const PartialDiagnostic &FirstNote, 6303 SourceRange FirstParenRange, 6304 const PartialDiagnostic &SecondNote, 6305 SourceRange SecondParenRange) { 6306 Self.Diag(Loc, PD); 6307 6308 if (!FirstNote.getDiagID()) 6309 return; 6310 6311 SourceLocation EndLoc = Self.PP.getLocForEndOfToken(FirstParenRange.getEnd()); 6312 if (!FirstParenRange.getEnd().isFileID() || EndLoc.isInvalid()) { 6313 // We can't display the parentheses, so just return. 6314 return; 6315 } 6316 6317 Self.Diag(Loc, FirstNote) 6318 << FixItHint::CreateInsertion(FirstParenRange.getBegin(), "(") 6319 << FixItHint::CreateInsertion(EndLoc, ")"); 6320 6321 if (!SecondNote.getDiagID()) 6322 return; 6323 6324 EndLoc = Self.PP.getLocForEndOfToken(SecondParenRange.getEnd()); 6325 if (!SecondParenRange.getEnd().isFileID() || EndLoc.isInvalid()) { 6326 // We can't display the parentheses, so just dig the 6327 // warning/error and return. 6328 Self.Diag(Loc, SecondNote); 6329 return; 6330 } 6331 6332 Self.Diag(Loc, SecondNote) 6333 << FixItHint::CreateInsertion(SecondParenRange.getBegin(), "(") 6334 << FixItHint::CreateInsertion(EndLoc, ")"); 6335} 6336 6337/// DiagnoseBitwisePrecedence - Emit a warning when bitwise and comparison 6338/// operators are mixed in a way that suggests that the programmer forgot that 6339/// comparison operators have higher precedence. The most typical example of 6340/// such code is "flags & 0x0020 != 0", which is equivalent to "flags & 1". 6341static void DiagnoseBitwisePrecedence(Sema &Self, BinaryOperator::Opcode Opc, 6342 SourceLocation OpLoc,Expr *lhs,Expr *rhs){ 6343 typedef BinaryOperator BinOp; 6344 BinOp::Opcode lhsopc = static_cast<BinOp::Opcode>(-1), 6345 rhsopc = static_cast<BinOp::Opcode>(-1); 6346 if (BinOp *BO = dyn_cast<BinOp>(lhs)) 6347 lhsopc = BO->getOpcode(); 6348 if (BinOp *BO = dyn_cast<BinOp>(rhs)) 6349 rhsopc = BO->getOpcode(); 6350 6351 // Subs are not binary operators. 6352 if (lhsopc == -1 && rhsopc == -1) 6353 return; 6354 6355 // Bitwise operations are sometimes used as eager logical ops. 6356 // Don't diagnose this. 6357 if ((BinOp::isComparisonOp(lhsopc) || BinOp::isBitwiseOp(lhsopc)) && 6358 (BinOp::isComparisonOp(rhsopc) || BinOp::isBitwiseOp(rhsopc))) 6359 return; 6360 6361 if (BinOp::isComparisonOp(lhsopc)) 6362 SuggestParentheses(Self, OpLoc, 6363 Self.PDiag(diag::warn_precedence_bitwise_rel) 6364 << SourceRange(lhs->getLocStart(), OpLoc) 6365 << BinOp::getOpcodeStr(Opc) << BinOp::getOpcodeStr(lhsopc), 6366 Self.PDiag(diag::note_precedence_bitwise_first) 6367 << BinOp::getOpcodeStr(Opc), 6368 SourceRange(cast<BinOp>(lhs)->getRHS()->getLocStart(), rhs->getLocEnd()), 6369 Self.PDiag(diag::note_precedence_bitwise_silence) 6370 << BinOp::getOpcodeStr(lhsopc), 6371 lhs->getSourceRange()); 6372 else if (BinOp::isComparisonOp(rhsopc)) 6373 SuggestParentheses(Self, OpLoc, 6374 Self.PDiag(diag::warn_precedence_bitwise_rel) 6375 << SourceRange(OpLoc, rhs->getLocEnd()) 6376 << BinOp::getOpcodeStr(Opc) << BinOp::getOpcodeStr(rhsopc), 6377 Self.PDiag(diag::note_precedence_bitwise_first) 6378 << BinOp::getOpcodeStr(Opc), 6379 SourceRange(lhs->getLocEnd(), cast<BinOp>(rhs)->getLHS()->getLocStart()), 6380 Self.PDiag(diag::note_precedence_bitwise_silence) 6381 << BinOp::getOpcodeStr(rhsopc), 6382 rhs->getSourceRange()); 6383} 6384 6385/// DiagnoseBinOpPrecedence - Emit warnings for expressions with tricky 6386/// precedence. This currently diagnoses only "arg1 'bitwise' arg2 'eq' arg3". 6387/// But it could also warn about arg1 && arg2 || arg3, as GCC 4.3+ does. 6388static void DiagnoseBinOpPrecedence(Sema &Self, BinaryOperator::Opcode Opc, 6389 SourceLocation OpLoc, Expr *lhs, Expr *rhs){ 6390 if (BinaryOperator::isBitwiseOp(Opc)) 6391 DiagnoseBitwisePrecedence(Self, Opc, OpLoc, lhs, rhs); 6392} 6393 6394// Binary Operators. 'Tok' is the token for the operator. 6395Action::OwningExprResult Sema::ActOnBinOp(Scope *S, SourceLocation TokLoc, 6396 tok::TokenKind Kind, 6397 ExprArg LHS, ExprArg RHS) { 6398 BinaryOperator::Opcode Opc = ConvertTokenKindToBinaryOpcode(Kind); 6399 Expr *lhs = LHS.takeAs<Expr>(), *rhs = RHS.takeAs<Expr>(); 6400 6401 assert((lhs != 0) && "ActOnBinOp(): missing left expression"); 6402 assert((rhs != 0) && "ActOnBinOp(): missing right expression"); 6403 6404 // Emit warnings for tricky precedence issues, e.g. "bitfield & 0x4 == 0" 6405 DiagnoseBinOpPrecedence(*this, Opc, TokLoc, lhs, rhs); 6406 6407 return BuildBinOp(S, TokLoc, Opc, lhs, rhs); 6408} 6409 6410Action::OwningExprResult Sema::BuildBinOp(Scope *S, SourceLocation OpLoc, 6411 BinaryOperator::Opcode Opc, 6412 Expr *lhs, Expr *rhs) { 6413 if (getLangOptions().CPlusPlus && 6414 (lhs->getType()->isOverloadableType() || 6415 rhs->getType()->isOverloadableType())) { 6416 // Find all of the overloaded operators visible from this 6417 // point. We perform both an operator-name lookup from the local 6418 // scope and an argument-dependent lookup based on the types of 6419 // the arguments. 6420 UnresolvedSet<16> Functions; 6421 OverloadedOperatorKind OverOp = BinaryOperator::getOverloadedOperator(Opc); 6422 if (S && OverOp != OO_None) 6423 LookupOverloadedOperatorName(OverOp, S, lhs->getType(), rhs->getType(), 6424 Functions); 6425 6426 // Build the (potentially-overloaded, potentially-dependent) 6427 // binary operation. 6428 return CreateOverloadedBinOp(OpLoc, Opc, Functions, lhs, rhs); 6429 } 6430 6431 // Build a built-in binary operation. 6432 return CreateBuiltinBinOp(OpLoc, Opc, lhs, rhs); 6433} 6434 6435Action::OwningExprResult Sema::CreateBuiltinUnaryOp(SourceLocation OpLoc, 6436 unsigned OpcIn, 6437 ExprArg InputArg) { 6438 UnaryOperator::Opcode Opc = static_cast<UnaryOperator::Opcode>(OpcIn); 6439 6440 // FIXME: Input is modified below, but InputArg is not updated appropriately. 6441 Expr *Input = (Expr *)InputArg.get(); 6442 QualType resultType; 6443 switch (Opc) { 6444 case UnaryOperator::OffsetOf: 6445 assert(false && "Invalid unary operator"); 6446 break; 6447 6448 case UnaryOperator::PreInc: 6449 case UnaryOperator::PreDec: 6450 case UnaryOperator::PostInc: 6451 case UnaryOperator::PostDec: 6452 resultType = CheckIncrementDecrementOperand(Input, OpLoc, 6453 Opc == UnaryOperator::PreInc || 6454 Opc == UnaryOperator::PostInc, 6455 Opc == UnaryOperator::PreInc || 6456 Opc == UnaryOperator::PreDec); 6457 break; 6458 case UnaryOperator::AddrOf: 6459 resultType = CheckAddressOfOperand(Input, OpLoc); 6460 break; 6461 case UnaryOperator::Deref: 6462 DefaultFunctionArrayLvalueConversion(Input); 6463 resultType = CheckIndirectionOperand(Input, OpLoc); 6464 break; 6465 case UnaryOperator::Plus: 6466 case UnaryOperator::Minus: 6467 UsualUnaryConversions(Input); 6468 resultType = Input->getType(); 6469 if (resultType->isDependentType()) 6470 break; 6471 if (resultType->isArithmeticType()) // C99 6.5.3.3p1 6472 break; 6473 else if (getLangOptions().CPlusPlus && // C++ [expr.unary.op]p6-7 6474 resultType->isEnumeralType()) 6475 break; 6476 else if (getLangOptions().CPlusPlus && // C++ [expr.unary.op]p6 6477 Opc == UnaryOperator::Plus && 6478 resultType->isPointerType()) 6479 break; 6480 6481 return ExprError(Diag(OpLoc, diag::err_typecheck_unary_expr) 6482 << resultType << Input->getSourceRange()); 6483 case UnaryOperator::Not: // bitwise complement 6484 UsualUnaryConversions(Input); 6485 resultType = Input->getType(); 6486 if (resultType->isDependentType()) 6487 break; 6488 // C99 6.5.3.3p1. We allow complex int and float as a GCC extension. 6489 if (resultType->isComplexType() || resultType->isComplexIntegerType()) 6490 // C99 does not support '~' for complex conjugation. 6491 Diag(OpLoc, diag::ext_integer_complement_complex) 6492 << resultType << Input->getSourceRange(); 6493 else if (!resultType->isIntegerType()) 6494 return ExprError(Diag(OpLoc, diag::err_typecheck_unary_expr) 6495 << resultType << Input->getSourceRange()); 6496 break; 6497 case UnaryOperator::LNot: // logical negation 6498 // Unlike +/-/~, integer promotions aren't done here (C99 6.5.3.3p5). 6499 DefaultFunctionArrayLvalueConversion(Input); 6500 resultType = Input->getType(); 6501 if (resultType->isDependentType()) 6502 break; 6503 if (!resultType->isScalarType()) // C99 6.5.3.3p1 6504 return ExprError(Diag(OpLoc, diag::err_typecheck_unary_expr) 6505 << resultType << Input->getSourceRange()); 6506 // LNot always has type int. C99 6.5.3.3p5. 6507 // In C++, it's bool. C++ 5.3.1p8 6508 resultType = getLangOptions().CPlusPlus ? Context.BoolTy : Context.IntTy; 6509 break; 6510 case UnaryOperator::Real: 6511 case UnaryOperator::Imag: 6512 resultType = CheckRealImagOperand(Input, OpLoc, Opc == UnaryOperator::Real); 6513 break; 6514 case UnaryOperator::Extension: 6515 resultType = Input->getType(); 6516 break; 6517 } 6518 if (resultType.isNull()) 6519 return ExprError(); 6520 6521 InputArg.release(); 6522 return Owned(new (Context) UnaryOperator(Input, Opc, resultType, OpLoc)); 6523} 6524 6525Action::OwningExprResult Sema::BuildUnaryOp(Scope *S, SourceLocation OpLoc, 6526 UnaryOperator::Opcode Opc, 6527 ExprArg input) { 6528 Expr *Input = (Expr*)input.get(); 6529 if (getLangOptions().CPlusPlus && Input->getType()->isOverloadableType() && 6530 Opc != UnaryOperator::Extension) { 6531 // Find all of the overloaded operators visible from this 6532 // point. We perform both an operator-name lookup from the local 6533 // scope and an argument-dependent lookup based on the types of 6534 // the arguments. 6535 UnresolvedSet<16> Functions; 6536 OverloadedOperatorKind OverOp = UnaryOperator::getOverloadedOperator(Opc); 6537 if (S && OverOp != OO_None) 6538 LookupOverloadedOperatorName(OverOp, S, Input->getType(), QualType(), 6539 Functions); 6540 6541 return CreateOverloadedUnaryOp(OpLoc, Opc, Functions, move(input)); 6542 } 6543 6544 return CreateBuiltinUnaryOp(OpLoc, Opc, move(input)); 6545} 6546 6547// Unary Operators. 'Tok' is the token for the operator. 6548Action::OwningExprResult Sema::ActOnUnaryOp(Scope *S, SourceLocation OpLoc, 6549 tok::TokenKind Op, ExprArg input) { 6550 return BuildUnaryOp(S, OpLoc, ConvertTokenKindToUnaryOpcode(Op), move(input)); 6551} 6552 6553/// ActOnAddrLabel - Parse the GNU address of label extension: "&&foo". 6554Sema::OwningExprResult Sema::ActOnAddrLabel(SourceLocation OpLoc, 6555 SourceLocation LabLoc, 6556 IdentifierInfo *LabelII) { 6557 // Look up the record for this label identifier. 6558 LabelStmt *&LabelDecl = getLabelMap()[LabelII]; 6559 6560 // If we haven't seen this label yet, create a forward reference. It 6561 // will be validated and/or cleaned up in ActOnFinishFunctionBody. 6562 if (LabelDecl == 0) 6563 LabelDecl = new (Context) LabelStmt(LabLoc, LabelII, 0); 6564 6565 // Create the AST node. The address of a label always has type 'void*'. 6566 return Owned(new (Context) AddrLabelExpr(OpLoc, LabLoc, LabelDecl, 6567 Context.getPointerType(Context.VoidTy))); 6568} 6569 6570Sema::OwningExprResult 6571Sema::ActOnStmtExpr(SourceLocation LPLoc, StmtArg substmt, 6572 SourceLocation RPLoc) { // "({..})" 6573 Stmt *SubStmt = static_cast<Stmt*>(substmt.get()); 6574 assert(SubStmt && isa<CompoundStmt>(SubStmt) && "Invalid action invocation!"); 6575 CompoundStmt *Compound = cast<CompoundStmt>(SubStmt); 6576 6577 bool isFileScope 6578 = (getCurFunctionOrMethodDecl() == 0) && (getCurBlock() == 0); 6579 if (isFileScope) 6580 return ExprError(Diag(LPLoc, diag::err_stmtexpr_file_scope)); 6581 6582 // FIXME: there are a variety of strange constraints to enforce here, for 6583 // example, it is not possible to goto into a stmt expression apparently. 6584 // More semantic analysis is needed. 6585 6586 // If there are sub stmts in the compound stmt, take the type of the last one 6587 // as the type of the stmtexpr. 6588 QualType Ty = Context.VoidTy; 6589 6590 if (!Compound->body_empty()) { 6591 Stmt *LastStmt = Compound->body_back(); 6592 // If LastStmt is a label, skip down through into the body. 6593 while (LabelStmt *Label = dyn_cast<LabelStmt>(LastStmt)) 6594 LastStmt = Label->getSubStmt(); 6595 6596 if (Expr *LastExpr = dyn_cast<Expr>(LastStmt)) 6597 Ty = LastExpr->getType(); 6598 } 6599 6600 // FIXME: Check that expression type is complete/non-abstract; statement 6601 // expressions are not lvalues. 6602 6603 substmt.release(); 6604 return Owned(new (Context) StmtExpr(Compound, Ty, LPLoc, RPLoc)); 6605} 6606 6607Sema::OwningExprResult Sema::BuildBuiltinOffsetOf(SourceLocation BuiltinLoc, 6608 TypeSourceInfo *TInfo, 6609 OffsetOfComponent *CompPtr, 6610 unsigned NumComponents, 6611 SourceLocation RParenLoc) { 6612 QualType ArgTy = TInfo->getType(); 6613 bool Dependent = ArgTy->isDependentType(); 6614 SourceRange TypeRange = TInfo->getTypeLoc().getLocalSourceRange(); 6615 6616 // We must have at least one component that refers to the type, and the first 6617 // one is known to be a field designator. Verify that the ArgTy represents 6618 // a struct/union/class. 6619 if (!Dependent && !ArgTy->isRecordType()) 6620 return ExprError(Diag(BuiltinLoc, diag::err_offsetof_record_type) 6621 << ArgTy << TypeRange); 6622 6623 // Type must be complete per C99 7.17p3 because a declaring a variable 6624 // with an incomplete type would be ill-formed. 6625 if (!Dependent 6626 && RequireCompleteType(BuiltinLoc, ArgTy, 6627 PDiag(diag::err_offsetof_incomplete_type) 6628 << TypeRange)) 6629 return ExprError(); 6630 6631 // offsetof with non-identifier designators (e.g. "offsetof(x, a.b[c])") are a 6632 // GCC extension, diagnose them. 6633 // FIXME: This diagnostic isn't actually visible because the location is in 6634 // a system header! 6635 if (NumComponents != 1) 6636 Diag(BuiltinLoc, diag::ext_offsetof_extended_field_designator) 6637 << SourceRange(CompPtr[1].LocStart, CompPtr[NumComponents-1].LocEnd); 6638 6639 bool DidWarnAboutNonPOD = false; 6640 QualType CurrentType = ArgTy; 6641 typedef OffsetOfExpr::OffsetOfNode OffsetOfNode; 6642 llvm::SmallVector<OffsetOfNode, 4> Comps; 6643 llvm::SmallVector<Expr*, 4> Exprs; 6644 for (unsigned i = 0; i != NumComponents; ++i) { 6645 const OffsetOfComponent &OC = CompPtr[i]; 6646 if (OC.isBrackets) { 6647 // Offset of an array sub-field. TODO: Should we allow vector elements? 6648 if (!CurrentType->isDependentType()) { 6649 const ArrayType *AT = Context.getAsArrayType(CurrentType); 6650 if(!AT) 6651 return ExprError(Diag(OC.LocEnd, diag::err_offsetof_array_type) 6652 << CurrentType); 6653 CurrentType = AT->getElementType(); 6654 } else 6655 CurrentType = Context.DependentTy; 6656 6657 // The expression must be an integral expression. 6658 // FIXME: An integral constant expression? 6659 Expr *Idx = static_cast<Expr*>(OC.U.E); 6660 if (!Idx->isTypeDependent() && !Idx->isValueDependent() && 6661 !Idx->getType()->isIntegerType()) 6662 return ExprError(Diag(Idx->getLocStart(), 6663 diag::err_typecheck_subscript_not_integer) 6664 << Idx->getSourceRange()); 6665 6666 // Record this array index. 6667 Comps.push_back(OffsetOfNode(OC.LocStart, Exprs.size(), OC.LocEnd)); 6668 Exprs.push_back(Idx); 6669 continue; 6670 } 6671 6672 // Offset of a field. 6673 if (CurrentType->isDependentType()) { 6674 // We have the offset of a field, but we can't look into the dependent 6675 // type. Just record the identifier of the field. 6676 Comps.push_back(OffsetOfNode(OC.LocStart, OC.U.IdentInfo, OC.LocEnd)); 6677 CurrentType = Context.DependentTy; 6678 continue; 6679 } 6680 6681 // We need to have a complete type to look into. 6682 if (RequireCompleteType(OC.LocStart, CurrentType, 6683 diag::err_offsetof_incomplete_type)) 6684 return ExprError(); 6685 6686 // Look for the designated field. 6687 const RecordType *RC = CurrentType->getAs<RecordType>(); 6688 if (!RC) 6689 return ExprError(Diag(OC.LocEnd, diag::err_offsetof_record_type) 6690 << CurrentType); 6691 RecordDecl *RD = RC->getDecl(); 6692 6693 // C++ [lib.support.types]p5: 6694 // The macro offsetof accepts a restricted set of type arguments in this 6695 // International Standard. type shall be a POD structure or a POD union 6696 // (clause 9). 6697 if (CXXRecordDecl *CRD = dyn_cast<CXXRecordDecl>(RD)) { 6698 if (!CRD->isPOD() && !DidWarnAboutNonPOD && 6699 DiagRuntimeBehavior(BuiltinLoc, 6700 PDiag(diag::warn_offsetof_non_pod_type) 6701 << SourceRange(CompPtr[0].LocStart, OC.LocEnd) 6702 << CurrentType)) 6703 DidWarnAboutNonPOD = true; 6704 } 6705 6706 // Look for the field. 6707 LookupResult R(*this, OC.U.IdentInfo, OC.LocStart, LookupMemberName); 6708 LookupQualifiedName(R, RD); 6709 FieldDecl *MemberDecl = R.getAsSingle<FieldDecl>(); 6710 if (!MemberDecl) 6711 return ExprError(Diag(BuiltinLoc, diag::err_no_member) 6712 << OC.U.IdentInfo << RD << SourceRange(OC.LocStart, 6713 OC.LocEnd)); 6714 6715 // C99 7.17p3: 6716 // (If the specified member is a bit-field, the behavior is undefined.) 6717 // 6718 // We diagnose this as an error. 6719 if (MemberDecl->getBitWidth()) { 6720 Diag(OC.LocEnd, diag::err_offsetof_bitfield) 6721 << MemberDecl->getDeclName() 6722 << SourceRange(BuiltinLoc, RParenLoc); 6723 Diag(MemberDecl->getLocation(), diag::note_bitfield_decl); 6724 return ExprError(); 6725 } 6726 6727 // If the member was found in a base class, introduce OffsetOfNodes for 6728 // the base class indirections. 6729 CXXBasePaths Paths(/*FindAmbiguities=*/true, /*RecordPaths=*/true, 6730 /*DetectVirtual=*/false); 6731 if (IsDerivedFrom(CurrentType, 6732 Context.getTypeDeclType(MemberDecl->getParent()), 6733 Paths)) { 6734 CXXBasePath &Path = Paths.front(); 6735 for (CXXBasePath::iterator B = Path.begin(), BEnd = Path.end(); 6736 B != BEnd; ++B) 6737 Comps.push_back(OffsetOfNode(B->Base)); 6738 } 6739 6740 if (cast<RecordDecl>(MemberDecl->getDeclContext())-> 6741 isAnonymousStructOrUnion()) { 6742 llvm::SmallVector<FieldDecl*, 4> Path; 6743 BuildAnonymousStructUnionMemberPath(MemberDecl, Path); 6744 unsigned n = Path.size(); 6745 for (int j = n - 1; j > -1; --j) 6746 Comps.push_back(OffsetOfNode(OC.LocStart, Path[j], OC.LocEnd)); 6747 } else { 6748 Comps.push_back(OffsetOfNode(OC.LocStart, MemberDecl, OC.LocEnd)); 6749 } 6750 CurrentType = MemberDecl->getType().getNonReferenceType(); 6751 } 6752 6753 return Owned(OffsetOfExpr::Create(Context, Context.getSizeType(), BuiltinLoc, 6754 TInfo, Comps.data(), Comps.size(), 6755 Exprs.data(), Exprs.size(), RParenLoc)); 6756} 6757 6758Sema::OwningExprResult Sema::ActOnBuiltinOffsetOf(Scope *S, 6759 SourceLocation BuiltinLoc, 6760 SourceLocation TypeLoc, 6761 TypeTy *argty, 6762 OffsetOfComponent *CompPtr, 6763 unsigned NumComponents, 6764 SourceLocation RPLoc) { 6765 6766 TypeSourceInfo *ArgTInfo; 6767 QualType ArgTy = GetTypeFromParser(argty, &ArgTInfo); 6768 if (ArgTy.isNull()) 6769 return ExprError(); 6770 6771 if (getLangOptions().CPlusPlus) { 6772 if (!ArgTInfo) 6773 ArgTInfo = Context.getTrivialTypeSourceInfo(ArgTy, TypeLoc); 6774 6775 return BuildBuiltinOffsetOf(BuiltinLoc, ArgTInfo, CompPtr, NumComponents, 6776 RPLoc); 6777 } 6778 6779 // FIXME: The code below is marked for death, once we have proper CodeGen 6780 // support for non-constant OffsetOf expressions. 6781 6782 bool Dependent = ArgTy->isDependentType(); 6783 6784 // We must have at least one component that refers to the type, and the first 6785 // one is known to be a field designator. Verify that the ArgTy represents 6786 // a struct/union/class. 6787 if (!Dependent && !ArgTy->isRecordType()) 6788 return ExprError(Diag(TypeLoc, diag::err_offsetof_record_type) << ArgTy); 6789 6790 // FIXME: Type must be complete per C99 7.17p3 because a declaring a variable 6791 // with an incomplete type would be illegal. 6792 6793 // Otherwise, create a null pointer as the base, and iteratively process 6794 // the offsetof designators. 6795 QualType ArgTyPtr = Context.getPointerType(ArgTy); 6796 Expr* Res = new (Context) ImplicitValueInitExpr(ArgTyPtr); 6797 Res = new (Context) UnaryOperator(Res, UnaryOperator::Deref, 6798 ArgTy, SourceLocation()); 6799 6800 // offsetof with non-identifier designators (e.g. "offsetof(x, a.b[c])") are a 6801 // GCC extension, diagnose them. 6802 // FIXME: This diagnostic isn't actually visible because the location is in 6803 // a system header! 6804 if (NumComponents != 1) 6805 Diag(BuiltinLoc, diag::ext_offsetof_extended_field_designator) 6806 << SourceRange(CompPtr[1].LocStart, CompPtr[NumComponents-1].LocEnd); 6807 6808 if (!Dependent) { 6809 bool DidWarnAboutNonPOD = false; 6810 6811 if (RequireCompleteType(TypeLoc, Res->getType(), 6812 diag::err_offsetof_incomplete_type)) 6813 return ExprError(); 6814 6815 // FIXME: Dependent case loses a lot of information here. And probably 6816 // leaks like a sieve. 6817 for (unsigned i = 0; i != NumComponents; ++i) { 6818 const OffsetOfComponent &OC = CompPtr[i]; 6819 if (OC.isBrackets) { 6820 // Offset of an array sub-field. TODO: Should we allow vector elements? 6821 const ArrayType *AT = Context.getAsArrayType(Res->getType()); 6822 if (!AT) { 6823 Res->Destroy(Context); 6824 return ExprError(Diag(OC.LocEnd, diag::err_offsetof_array_type) 6825 << Res->getType()); 6826 } 6827 6828 // FIXME: C++: Verify that operator[] isn't overloaded. 6829 6830 // Promote the array so it looks more like a normal array subscript 6831 // expression. 6832 DefaultFunctionArrayLvalueConversion(Res); 6833 6834 // C99 6.5.2.1p1 6835 Expr *Idx = static_cast<Expr*>(OC.U.E); 6836 // FIXME: Leaks Res 6837 if (!Idx->isTypeDependent() && !Idx->getType()->isIntegerType()) 6838 return ExprError(Diag(Idx->getLocStart(), 6839 diag::err_typecheck_subscript_not_integer) 6840 << Idx->getSourceRange()); 6841 6842 Res = new (Context) ArraySubscriptExpr(Res, Idx, AT->getElementType(), 6843 OC.LocEnd); 6844 continue; 6845 } 6846 6847 const RecordType *RC = Res->getType()->getAs<RecordType>(); 6848 if (!RC) { 6849 Res->Destroy(Context); 6850 return ExprError(Diag(OC.LocEnd, diag::err_offsetof_record_type) 6851 << Res->getType()); 6852 } 6853 6854 // Get the decl corresponding to this. 6855 RecordDecl *RD = RC->getDecl(); 6856 if (CXXRecordDecl *CRD = dyn_cast<CXXRecordDecl>(RD)) { 6857 if (!CRD->isPOD() && !DidWarnAboutNonPOD && 6858 DiagRuntimeBehavior(BuiltinLoc, 6859 PDiag(diag::warn_offsetof_non_pod_type) 6860 << SourceRange(CompPtr[0].LocStart, OC.LocEnd) 6861 << Res->getType())) 6862 DidWarnAboutNonPOD = true; 6863 } 6864 6865 LookupResult R(*this, OC.U.IdentInfo, OC.LocStart, LookupMemberName); 6866 LookupQualifiedName(R, RD); 6867 6868 FieldDecl *MemberDecl = R.getAsSingle<FieldDecl>(); 6869 // FIXME: Leaks Res 6870 if (!MemberDecl) 6871 return ExprError(Diag(BuiltinLoc, diag::err_no_member) 6872 << OC.U.IdentInfo << RD << SourceRange(OC.LocStart, OC.LocEnd)); 6873 6874 // C99 7.17p3: 6875 // (If the specified member is a bit-field, the behavior is undefined.) 6876 // 6877 // We diagnose this as an error. 6878 if (MemberDecl->getBitWidth()) { 6879 Diag(OC.LocEnd, diag::err_offsetof_bitfield) 6880 << MemberDecl->getDeclName() 6881 << SourceRange(BuiltinLoc, RPLoc); 6882 Diag(MemberDecl->getLocation(), diag::note_bitfield_decl); 6883 return ExprError(); 6884 } 6885 6886 // FIXME: C++: Verify that MemberDecl isn't a static field. 6887 // FIXME: Verify that MemberDecl isn't a bitfield. 6888 if (cast<RecordDecl>(MemberDecl->getDeclContext())->isAnonymousStructOrUnion()) { 6889 Res = BuildAnonymousStructUnionMemberReference( 6890 OC.LocEnd, MemberDecl, Res, OC.LocEnd).takeAs<Expr>(); 6891 } else { 6892 PerformObjectMemberConversion(Res, /*Qualifier=*/0, 6893 *R.begin(), MemberDecl); 6894 // MemberDecl->getType() doesn't get the right qualifiers, but it 6895 // doesn't matter here. 6896 Res = new (Context) MemberExpr(Res, false, MemberDecl, OC.LocEnd, 6897 MemberDecl->getType().getNonReferenceType()); 6898 } 6899 } 6900 } 6901 6902 return Owned(new (Context) UnaryOperator(Res, UnaryOperator::OffsetOf, 6903 Context.getSizeType(), BuiltinLoc)); 6904} 6905 6906 6907Sema::OwningExprResult Sema::ActOnTypesCompatibleExpr(SourceLocation BuiltinLoc, 6908 TypeTy *arg1,TypeTy *arg2, 6909 SourceLocation RPLoc) { 6910 // FIXME: Preserve type source info. 6911 QualType argT1 = GetTypeFromParser(arg1); 6912 QualType argT2 = GetTypeFromParser(arg2); 6913 6914 assert((!argT1.isNull() && !argT2.isNull()) && "Missing type argument(s)"); 6915 6916 if (getLangOptions().CPlusPlus) { 6917 Diag(BuiltinLoc, diag::err_types_compatible_p_in_cplusplus) 6918 << SourceRange(BuiltinLoc, RPLoc); 6919 return ExprError(); 6920 } 6921 6922 return Owned(new (Context) TypesCompatibleExpr(Context.IntTy, BuiltinLoc, 6923 argT1, argT2, RPLoc)); 6924} 6925 6926Sema::OwningExprResult Sema::ActOnChooseExpr(SourceLocation BuiltinLoc, 6927 ExprArg cond, 6928 ExprArg expr1, ExprArg expr2, 6929 SourceLocation RPLoc) { 6930 Expr *CondExpr = static_cast<Expr*>(cond.get()); 6931 Expr *LHSExpr = static_cast<Expr*>(expr1.get()); 6932 Expr *RHSExpr = static_cast<Expr*>(expr2.get()); 6933 6934 assert((CondExpr && LHSExpr && RHSExpr) && "Missing type argument(s)"); 6935 6936 QualType resType; 6937 bool ValueDependent = false; 6938 if (CondExpr->isTypeDependent() || CondExpr->isValueDependent()) { 6939 resType = Context.DependentTy; 6940 ValueDependent = true; 6941 } else { 6942 // The conditional expression is required to be a constant expression. 6943 llvm::APSInt condEval(32); 6944 SourceLocation ExpLoc; 6945 if (!CondExpr->isIntegerConstantExpr(condEval, Context, &ExpLoc)) 6946 return ExprError(Diag(ExpLoc, 6947 diag::err_typecheck_choose_expr_requires_constant) 6948 << CondExpr->getSourceRange()); 6949 6950 // If the condition is > zero, then the AST type is the same as the LSHExpr. 6951 resType = condEval.getZExtValue() ? LHSExpr->getType() : RHSExpr->getType(); 6952 ValueDependent = condEval.getZExtValue() ? LHSExpr->isValueDependent() 6953 : RHSExpr->isValueDependent(); 6954 } 6955 6956 cond.release(); expr1.release(); expr2.release(); 6957 return Owned(new (Context) ChooseExpr(BuiltinLoc, CondExpr, LHSExpr, RHSExpr, 6958 resType, RPLoc, 6959 resType->isDependentType(), 6960 ValueDependent)); 6961} 6962 6963//===----------------------------------------------------------------------===// 6964// Clang Extensions. 6965//===----------------------------------------------------------------------===// 6966 6967/// ActOnBlockStart - This callback is invoked when a block literal is started. 6968void Sema::ActOnBlockStart(SourceLocation CaretLoc, Scope *BlockScope) { 6969 BlockDecl *Block = BlockDecl::Create(Context, CurContext, CaretLoc); 6970 PushBlockScope(BlockScope, Block); 6971 CurContext->addDecl(Block); 6972 PushDeclContext(BlockScope, Block); 6973} 6974 6975void Sema::ActOnBlockArguments(Declarator &ParamInfo, Scope *CurScope) { 6976 assert(ParamInfo.getIdentifier()==0 && "block-id should have no identifier!"); 6977 BlockScopeInfo *CurBlock = getCurBlock(); 6978 6979 TypeSourceInfo *Sig = 0; 6980 QualType T = GetTypeForDeclarator(ParamInfo, CurScope, &Sig); 6981 CurBlock->TheDecl->setSignatureAsWritten(Sig); 6982 6983 QualType RetTy; 6984 if (const FunctionType *Fn = T->getAs<FunctionType>()) { 6985 RetTy = Fn->getResultType(); 6986 CurBlock->hasPrototype = isa<FunctionProtoType>(Fn); 6987 CurBlock->isVariadic = 6988 !isa<FunctionProtoType>(Fn) || cast<FunctionProtoType>(Fn)->isVariadic(); 6989 } else { 6990 RetTy = T; 6991 CurBlock->hasPrototype = true; 6992 CurBlock->isVariadic = false; 6993 } 6994 6995 CurBlock->TheDecl->setIsVariadic(CurBlock->isVariadic); 6996 6997 // Don't allow returning an array by value. 6998 if (RetTy->isArrayType()) { 6999 Diag(ParamInfo.getSourceRange().getBegin(), diag::err_block_returns_array); 7000 return; 7001 } 7002 7003 // Don't allow returning a objc interface by value. 7004 if (RetTy->isObjCObjectType()) { 7005 Diag(ParamInfo.getSourceRange().getBegin(), 7006 diag::err_object_cannot_be_passed_returned_by_value) << 0 << RetTy; 7007 return; 7008 } 7009 7010 // Context.DependentTy is used as a placeholder for a missing block 7011 // return type. 7012 if (RetTy != Context.DependentTy) 7013 CurBlock->ReturnType = RetTy; 7014 7015 // Push block parameters from the declarator if we had them. 7016 if (isa<FunctionProtoType>(T)) { 7017 FunctionProtoTypeLoc TL = cast<FunctionProtoTypeLoc>(Sig->getTypeLoc()); 7018 for (unsigned I = 0, E = TL.getNumArgs(); I != E; ++I) { 7019 ParmVarDecl *Param = TL.getArg(I); 7020 if (Param->getIdentifier() == 0 && 7021 !Param->isImplicit() && 7022 !Param->isInvalidDecl() && 7023 !getLangOptions().CPlusPlus) 7024 Diag(Param->getLocation(), diag::err_parameter_name_omitted); 7025 CurBlock->Params.push_back(Param); 7026 } 7027 7028 // Fake up parameter variables if we have a typedef, like 7029 // ^ fntype { ... } 7030 } else if (const FunctionProtoType *Fn = T->getAs<FunctionProtoType>()) { 7031 for (FunctionProtoType::arg_type_iterator 7032 I = Fn->arg_type_begin(), E = Fn->arg_type_end(); I != E; ++I) { 7033 ParmVarDecl *Param = 7034 BuildParmVarDeclForTypedef(CurBlock->TheDecl, 7035 ParamInfo.getSourceRange().getBegin(), 7036 *I); 7037 CurBlock->Params.push_back(Param); 7038 } 7039 } 7040 7041 // Set the parmaeters on the block decl. 7042 if (!CurBlock->Params.empty()) 7043 CurBlock->TheDecl->setParams(CurBlock->Params.data(), 7044 CurBlock->Params.size()); 7045 7046 // Finally we can process decl attributes. 7047 ProcessDeclAttributes(CurScope, CurBlock->TheDecl, ParamInfo); 7048 7049 if (!CurBlock->isVariadic && CurBlock->TheDecl->getAttr<SentinelAttr>()) { 7050 Diag(ParamInfo.getAttributes()->getLoc(), 7051 diag::warn_attribute_sentinel_not_variadic) << 1; 7052 // FIXME: remove the attribute. 7053 } 7054 7055 // Put the parameter variables in scope. We can bail out immediately 7056 // if we don't have any. 7057 if (CurBlock->Params.empty()) 7058 return; 7059 7060 bool ShouldCheckShadow = 7061 Diags.getDiagnosticLevel(diag::warn_decl_shadow) != Diagnostic::Ignored; 7062 7063 for (BlockDecl::param_iterator AI = CurBlock->TheDecl->param_begin(), 7064 E = CurBlock->TheDecl->param_end(); AI != E; ++AI) { 7065 (*AI)->setOwningFunction(CurBlock->TheDecl); 7066 7067 // If this has an identifier, add it to the scope stack. 7068 if ((*AI)->getIdentifier()) { 7069 if (ShouldCheckShadow) 7070 CheckShadow(CurBlock->TheScope, *AI); 7071 7072 PushOnScopeChains(*AI, CurBlock->TheScope); 7073 } 7074 } 7075} 7076 7077/// ActOnBlockError - If there is an error parsing a block, this callback 7078/// is invoked to pop the information about the block from the action impl. 7079void Sema::ActOnBlockError(SourceLocation CaretLoc, Scope *CurScope) { 7080 // Pop off CurBlock, handle nested blocks. 7081 PopDeclContext(); 7082 PopFunctionOrBlockScope(); 7083 // FIXME: Delete the ParmVarDecl objects as well??? 7084} 7085 7086/// ActOnBlockStmtExpr - This is called when the body of a block statement 7087/// literal was successfully completed. ^(int x){...} 7088Sema::OwningExprResult Sema::ActOnBlockStmtExpr(SourceLocation CaretLoc, 7089 StmtArg body, Scope *CurScope) { 7090 // If blocks are disabled, emit an error. 7091 if (!LangOpts.Blocks) 7092 Diag(CaretLoc, diag::err_blocks_disable); 7093 7094 BlockScopeInfo *BSI = cast<BlockScopeInfo>(FunctionScopes.back()); 7095 7096 PopDeclContext(); 7097 7098 QualType RetTy = Context.VoidTy; 7099 if (!BSI->ReturnType.isNull()) 7100 RetTy = BSI->ReturnType; 7101 7102 llvm::SmallVector<QualType, 8> ArgTypes; 7103 for (unsigned i = 0, e = BSI->Params.size(); i != e; ++i) 7104 ArgTypes.push_back(BSI->Params[i]->getType()); 7105 7106 bool NoReturn = BSI->TheDecl->getAttr<NoReturnAttr>(); 7107 QualType BlockTy; 7108 if (!BSI->hasPrototype) 7109 BlockTy = Context.getFunctionType(RetTy, 0, 0, false, 0, false, false, 0, 0, 7110 FunctionType::ExtInfo(NoReturn, 0, CC_Default)); 7111 else 7112 BlockTy = Context.getFunctionType(RetTy, ArgTypes.data(), ArgTypes.size(), 7113 BSI->isVariadic, 0, false, false, 0, 0, 7114 FunctionType::ExtInfo(NoReturn, 0, CC_Default)); 7115 7116 // FIXME: Check that return/parameter types are complete/non-abstract 7117 DiagnoseUnusedParameters(BSI->Params.begin(), BSI->Params.end()); 7118 BlockTy = Context.getBlockPointerType(BlockTy); 7119 7120 // If needed, diagnose invalid gotos and switches in the block. 7121 if (FunctionNeedsScopeChecking() && !hasAnyErrorsInThisFunction()) 7122 DiagnoseInvalidJumps(static_cast<CompoundStmt*>(body.get())); 7123 7124 BSI->TheDecl->setBody(body.takeAs<CompoundStmt>()); 7125 7126 bool Good = true; 7127 // Check goto/label use. 7128 for (llvm::DenseMap<IdentifierInfo*, LabelStmt*>::iterator 7129 I = BSI->LabelMap.begin(), E = BSI->LabelMap.end(); I != E; ++I) { 7130 LabelStmt *L = I->second; 7131 7132 // Verify that we have no forward references left. If so, there was a goto 7133 // or address of a label taken, but no definition of it. 7134 if (L->getSubStmt() != 0) 7135 continue; 7136 7137 // Emit error. 7138 Diag(L->getIdentLoc(), diag::err_undeclared_label_use) << L->getName(); 7139 Good = false; 7140 } 7141 if (!Good) { 7142 PopFunctionOrBlockScope(); 7143 return ExprError(); 7144 } 7145 7146 // Issue any analysis-based warnings. 7147 const sema::AnalysisBasedWarnings::Policy &WP = 7148 AnalysisWarnings.getDefaultPolicy(); 7149 AnalysisWarnings.IssueWarnings(WP, BSI->TheDecl, BlockTy); 7150 7151 Expr *Result = new (Context) BlockExpr(BSI->TheDecl, BlockTy, 7152 BSI->hasBlockDeclRefExprs); 7153 PopFunctionOrBlockScope(); 7154 return Owned(Result); 7155} 7156 7157Sema::OwningExprResult Sema::ActOnVAArg(SourceLocation BuiltinLoc, 7158 ExprArg expr, TypeTy *type, 7159 SourceLocation RPLoc) { 7160 QualType T = GetTypeFromParser(type); 7161 Expr *E = static_cast<Expr*>(expr.get()); 7162 Expr *OrigExpr = E; 7163 7164 InitBuiltinVaListType(); 7165 7166 // Get the va_list type 7167 QualType VaListType = Context.getBuiltinVaListType(); 7168 if (VaListType->isArrayType()) { 7169 // Deal with implicit array decay; for example, on x86-64, 7170 // va_list is an array, but it's supposed to decay to 7171 // a pointer for va_arg. 7172 VaListType = Context.getArrayDecayedType(VaListType); 7173 // Make sure the input expression also decays appropriately. 7174 UsualUnaryConversions(E); 7175 } else { 7176 // Otherwise, the va_list argument must be an l-value because 7177 // it is modified by va_arg. 7178 if (!E->isTypeDependent() && 7179 CheckForModifiableLvalue(E, BuiltinLoc, *this)) 7180 return ExprError(); 7181 } 7182 7183 if (!E->isTypeDependent() && 7184 !Context.hasSameType(VaListType, E->getType())) { 7185 return ExprError(Diag(E->getLocStart(), 7186 diag::err_first_argument_to_va_arg_not_of_type_va_list) 7187 << OrigExpr->getType() << E->getSourceRange()); 7188 } 7189 7190 // FIXME: Check that type is complete/non-abstract 7191 // FIXME: Warn if a non-POD type is passed in. 7192 7193 expr.release(); 7194 return Owned(new (Context) VAArgExpr(BuiltinLoc, E, T.getNonReferenceType(), 7195 RPLoc)); 7196} 7197 7198Sema::OwningExprResult Sema::ActOnGNUNullExpr(SourceLocation TokenLoc) { 7199 // The type of __null will be int or long, depending on the size of 7200 // pointers on the target. 7201 QualType Ty; 7202 if (Context.Target.getPointerWidth(0) == Context.Target.getIntWidth()) 7203 Ty = Context.IntTy; 7204 else 7205 Ty = Context.LongTy; 7206 7207 return Owned(new (Context) GNUNullExpr(Ty, TokenLoc)); 7208} 7209 7210static void MakeObjCStringLiteralFixItHint(Sema& SemaRef, QualType DstType, 7211 Expr *SrcExpr, FixItHint &Hint) { 7212 if (!SemaRef.getLangOptions().ObjC1) 7213 return; 7214 7215 const ObjCObjectPointerType *PT = DstType->getAs<ObjCObjectPointerType>(); 7216 if (!PT) 7217 return; 7218 7219 // Check if the destination is of type 'id'. 7220 if (!PT->isObjCIdType()) { 7221 // Check if the destination is the 'NSString' interface. 7222 const ObjCInterfaceDecl *ID = PT->getInterfaceDecl(); 7223 if (!ID || !ID->getIdentifier()->isStr("NSString")) 7224 return; 7225 } 7226 7227 // Strip off any parens and casts. 7228 StringLiteral *SL = dyn_cast<StringLiteral>(SrcExpr->IgnoreParenCasts()); 7229 if (!SL || SL->isWide()) 7230 return; 7231 7232 Hint = FixItHint::CreateInsertion(SL->getLocStart(), "@"); 7233} 7234 7235bool Sema::DiagnoseAssignmentResult(AssignConvertType ConvTy, 7236 SourceLocation Loc, 7237 QualType DstType, QualType SrcType, 7238 Expr *SrcExpr, AssignmentAction Action, 7239 bool *Complained) { 7240 if (Complained) 7241 *Complained = false; 7242 7243 // Decode the result (notice that AST's are still created for extensions). 7244 bool isInvalid = false; 7245 unsigned DiagKind; 7246 FixItHint Hint; 7247 7248 switch (ConvTy) { 7249 default: assert(0 && "Unknown conversion type"); 7250 case Compatible: return false; 7251 case PointerToInt: 7252 DiagKind = diag::ext_typecheck_convert_pointer_int; 7253 break; 7254 case IntToPointer: 7255 DiagKind = diag::ext_typecheck_convert_int_pointer; 7256 break; 7257 case IncompatiblePointer: 7258 MakeObjCStringLiteralFixItHint(*this, DstType, SrcExpr, Hint); 7259 DiagKind = diag::ext_typecheck_convert_incompatible_pointer; 7260 break; 7261 case IncompatiblePointerSign: 7262 DiagKind = diag::ext_typecheck_convert_incompatible_pointer_sign; 7263 break; 7264 case FunctionVoidPointer: 7265 DiagKind = diag::ext_typecheck_convert_pointer_void_func; 7266 break; 7267 case CompatiblePointerDiscardsQualifiers: 7268 // If the qualifiers lost were because we were applying the 7269 // (deprecated) C++ conversion from a string literal to a char* 7270 // (or wchar_t*), then there was no error (C++ 4.2p2). FIXME: 7271 // Ideally, this check would be performed in 7272 // CheckPointerTypesForAssignment. However, that would require a 7273 // bit of refactoring (so that the second argument is an 7274 // expression, rather than a type), which should be done as part 7275 // of a larger effort to fix CheckPointerTypesForAssignment for 7276 // C++ semantics. 7277 if (getLangOptions().CPlusPlus && 7278 IsStringLiteralToNonConstPointerConversion(SrcExpr, DstType)) 7279 return false; 7280 DiagKind = diag::ext_typecheck_convert_discards_qualifiers; 7281 break; 7282 case IncompatibleNestedPointerQualifiers: 7283 DiagKind = diag::ext_nested_pointer_qualifier_mismatch; 7284 break; 7285 case IntToBlockPointer: 7286 DiagKind = diag::err_int_to_block_pointer; 7287 break; 7288 case IncompatibleBlockPointer: 7289 DiagKind = diag::err_typecheck_convert_incompatible_block_pointer; 7290 break; 7291 case IncompatibleObjCQualifiedId: 7292 // FIXME: Diagnose the problem in ObjCQualifiedIdTypesAreCompatible, since 7293 // it can give a more specific diagnostic. 7294 DiagKind = diag::warn_incompatible_qualified_id; 7295 break; 7296 case IncompatibleVectors: 7297 DiagKind = diag::warn_incompatible_vectors; 7298 break; 7299 case Incompatible: 7300 DiagKind = diag::err_typecheck_convert_incompatible; 7301 isInvalid = true; 7302 break; 7303 } 7304 7305 QualType FirstType, SecondType; 7306 switch (Action) { 7307 case AA_Assigning: 7308 case AA_Initializing: 7309 // The destination type comes first. 7310 FirstType = DstType; 7311 SecondType = SrcType; 7312 break; 7313 7314 case AA_Returning: 7315 case AA_Passing: 7316 case AA_Converting: 7317 case AA_Sending: 7318 case AA_Casting: 7319 // The source type comes first. 7320 FirstType = SrcType; 7321 SecondType = DstType; 7322 break; 7323 } 7324 7325 Diag(Loc, DiagKind) << FirstType << SecondType << Action 7326 << SrcExpr->getSourceRange() << Hint; 7327 if (Complained) 7328 *Complained = true; 7329 return isInvalid; 7330} 7331 7332bool Sema::VerifyIntegerConstantExpression(const Expr *E, llvm::APSInt *Result){ 7333 llvm::APSInt ICEResult; 7334 if (E->isIntegerConstantExpr(ICEResult, Context)) { 7335 if (Result) 7336 *Result = ICEResult; 7337 return false; 7338 } 7339 7340 Expr::EvalResult EvalResult; 7341 7342 if (!E->Evaluate(EvalResult, Context) || !EvalResult.Val.isInt() || 7343 EvalResult.HasSideEffects) { 7344 Diag(E->getExprLoc(), diag::err_expr_not_ice) << E->getSourceRange(); 7345 7346 if (EvalResult.Diag) { 7347 // We only show the note if it's not the usual "invalid subexpression" 7348 // or if it's actually in a subexpression. 7349 if (EvalResult.Diag != diag::note_invalid_subexpr_in_ice || 7350 E->IgnoreParens() != EvalResult.DiagExpr->IgnoreParens()) 7351 Diag(EvalResult.DiagLoc, EvalResult.Diag); 7352 } 7353 7354 return true; 7355 } 7356 7357 Diag(E->getExprLoc(), diag::ext_expr_not_ice) << 7358 E->getSourceRange(); 7359 7360 if (EvalResult.Diag && 7361 Diags.getDiagnosticLevel(diag::ext_expr_not_ice) != Diagnostic::Ignored) 7362 Diag(EvalResult.DiagLoc, EvalResult.Diag); 7363 7364 if (Result) 7365 *Result = EvalResult.Val.getInt(); 7366 return false; 7367} 7368 7369void 7370Sema::PushExpressionEvaluationContext(ExpressionEvaluationContext NewContext) { 7371 ExprEvalContexts.push_back( 7372 ExpressionEvaluationContextRecord(NewContext, ExprTemporaries.size())); 7373} 7374 7375void 7376Sema::PopExpressionEvaluationContext() { 7377 // Pop the current expression evaluation context off the stack. 7378 ExpressionEvaluationContextRecord Rec = ExprEvalContexts.back(); 7379 ExprEvalContexts.pop_back(); 7380 7381 if (Rec.Context == PotentiallyPotentiallyEvaluated) { 7382 if (Rec.PotentiallyReferenced) { 7383 // Mark any remaining declarations in the current position of the stack 7384 // as "referenced". If they were not meant to be referenced, semantic 7385 // analysis would have eliminated them (e.g., in ActOnCXXTypeId). 7386 for (PotentiallyReferencedDecls::iterator 7387 I = Rec.PotentiallyReferenced->begin(), 7388 IEnd = Rec.PotentiallyReferenced->end(); 7389 I != IEnd; ++I) 7390 MarkDeclarationReferenced(I->first, I->second); 7391 } 7392 7393 if (Rec.PotentiallyDiagnosed) { 7394 // Emit any pending diagnostics. 7395 for (PotentiallyEmittedDiagnostics::iterator 7396 I = Rec.PotentiallyDiagnosed->begin(), 7397 IEnd = Rec.PotentiallyDiagnosed->end(); 7398 I != IEnd; ++I) 7399 Diag(I->first, I->second); 7400 } 7401 } 7402 7403 // When are coming out of an unevaluated context, clear out any 7404 // temporaries that we may have created as part of the evaluation of 7405 // the expression in that context: they aren't relevant because they 7406 // will never be constructed. 7407 if (Rec.Context == Unevaluated && 7408 ExprTemporaries.size() > Rec.NumTemporaries) 7409 ExprTemporaries.erase(ExprTemporaries.begin() + Rec.NumTemporaries, 7410 ExprTemporaries.end()); 7411 7412 // Destroy the popped expression evaluation record. 7413 Rec.Destroy(); 7414} 7415 7416/// \brief Note that the given declaration was referenced in the source code. 7417/// 7418/// This routine should be invoke whenever a given declaration is referenced 7419/// in the source code, and where that reference occurred. If this declaration 7420/// reference means that the the declaration is used (C++ [basic.def.odr]p2, 7421/// C99 6.9p3), then the declaration will be marked as used. 7422/// 7423/// \param Loc the location where the declaration was referenced. 7424/// 7425/// \param D the declaration that has been referenced by the source code. 7426void Sema::MarkDeclarationReferenced(SourceLocation Loc, Decl *D) { 7427 assert(D && "No declaration?"); 7428 7429 if (D->isUsed()) 7430 return; 7431 7432 // Mark a parameter or variable declaration "used", regardless of whether we're in a 7433 // template or not. The reason for this is that unevaluated expressions 7434 // (e.g. (void)sizeof()) constitute a use for warning purposes (-Wunused-variables and 7435 // -Wunused-parameters) 7436 if (isa<ParmVarDecl>(D) || 7437 (isa<VarDecl>(D) && D->getDeclContext()->isFunctionOrMethod())) { 7438 D->setUsed(true); 7439 return; 7440 } 7441 7442 if (!isa<VarDecl>(D) && !isa<FunctionDecl>(D)) 7443 return; 7444 7445 // Do not mark anything as "used" within a dependent context; wait for 7446 // an instantiation. 7447 if (CurContext->isDependentContext()) 7448 return; 7449 7450 switch (ExprEvalContexts.back().Context) { 7451 case Unevaluated: 7452 // We are in an expression that is not potentially evaluated; do nothing. 7453 return; 7454 7455 case PotentiallyEvaluated: 7456 // We are in a potentially-evaluated expression, so this declaration is 7457 // "used"; handle this below. 7458 break; 7459 7460 case PotentiallyPotentiallyEvaluated: 7461 // We are in an expression that may be potentially evaluated; queue this 7462 // declaration reference until we know whether the expression is 7463 // potentially evaluated. 7464 ExprEvalContexts.back().addReferencedDecl(Loc, D); 7465 return; 7466 } 7467 7468 // Note that this declaration has been used. 7469 if (CXXConstructorDecl *Constructor = dyn_cast<CXXConstructorDecl>(D)) { 7470 unsigned TypeQuals; 7471 if (Constructor->isImplicit() && Constructor->isDefaultConstructor()) { 7472 if (!Constructor->isUsed()) 7473 DefineImplicitDefaultConstructor(Loc, Constructor); 7474 } else if (Constructor->isImplicit() && 7475 Constructor->isCopyConstructor(TypeQuals)) { 7476 if (!Constructor->isUsed()) 7477 DefineImplicitCopyConstructor(Loc, Constructor, TypeQuals); 7478 } 7479 7480 MarkVTableUsed(Loc, Constructor->getParent()); 7481 } else if (CXXDestructorDecl *Destructor = dyn_cast<CXXDestructorDecl>(D)) { 7482 if (Destructor->isImplicit() && !Destructor->isUsed()) 7483 DefineImplicitDestructor(Loc, Destructor); 7484 if (Destructor->isVirtual()) 7485 MarkVTableUsed(Loc, Destructor->getParent()); 7486 } else if (CXXMethodDecl *MethodDecl = dyn_cast<CXXMethodDecl>(D)) { 7487 if (MethodDecl->isImplicit() && MethodDecl->isOverloadedOperator() && 7488 MethodDecl->getOverloadedOperator() == OO_Equal) { 7489 if (!MethodDecl->isUsed()) 7490 DefineImplicitCopyAssignment(Loc, MethodDecl); 7491 } else if (MethodDecl->isVirtual()) 7492 MarkVTableUsed(Loc, MethodDecl->getParent()); 7493 } 7494 if (FunctionDecl *Function = dyn_cast<FunctionDecl>(D)) { 7495 // Implicit instantiation of function templates and member functions of 7496 // class templates. 7497 if (Function->isImplicitlyInstantiable()) { 7498 bool AlreadyInstantiated = false; 7499 if (FunctionTemplateSpecializationInfo *SpecInfo 7500 = Function->getTemplateSpecializationInfo()) { 7501 if (SpecInfo->getPointOfInstantiation().isInvalid()) 7502 SpecInfo->setPointOfInstantiation(Loc); 7503 else if (SpecInfo->getTemplateSpecializationKind() 7504 == TSK_ImplicitInstantiation) 7505 AlreadyInstantiated = true; 7506 } else if (MemberSpecializationInfo *MSInfo 7507 = Function->getMemberSpecializationInfo()) { 7508 if (MSInfo->getPointOfInstantiation().isInvalid()) 7509 MSInfo->setPointOfInstantiation(Loc); 7510 else if (MSInfo->getTemplateSpecializationKind() 7511 == TSK_ImplicitInstantiation) 7512 AlreadyInstantiated = true; 7513 } 7514 7515 if (!AlreadyInstantiated) { 7516 if (isa<CXXRecordDecl>(Function->getDeclContext()) && 7517 cast<CXXRecordDecl>(Function->getDeclContext())->isLocalClass()) 7518 PendingLocalImplicitInstantiations.push_back(std::make_pair(Function, 7519 Loc)); 7520 else 7521 PendingImplicitInstantiations.push_back(std::make_pair(Function, 7522 Loc)); 7523 } 7524 } 7525 7526 // FIXME: keep track of references to static functions 7527 Function->setUsed(true); 7528 7529 return; 7530 } 7531 7532 if (VarDecl *Var = dyn_cast<VarDecl>(D)) { 7533 // Implicit instantiation of static data members of class templates. 7534 if (Var->isStaticDataMember() && 7535 Var->getInstantiatedFromStaticDataMember()) { 7536 MemberSpecializationInfo *MSInfo = Var->getMemberSpecializationInfo(); 7537 assert(MSInfo && "Missing member specialization information?"); 7538 if (MSInfo->getPointOfInstantiation().isInvalid() && 7539 MSInfo->getTemplateSpecializationKind()== TSK_ImplicitInstantiation) { 7540 MSInfo->setPointOfInstantiation(Loc); 7541 PendingImplicitInstantiations.push_back(std::make_pair(Var, Loc)); 7542 } 7543 } 7544 7545 // FIXME: keep track of references to static data? 7546 7547 D->setUsed(true); 7548 return; 7549 } 7550} 7551 7552namespace { 7553 // Mark all of the declarations referenced 7554 // FIXME: Not fully implemented yet! We need to have a better understanding 7555 // of when we're entering 7556 class MarkReferencedDecls : public RecursiveASTVisitor<MarkReferencedDecls> { 7557 Sema &S; 7558 SourceLocation Loc; 7559 7560 public: 7561 typedef RecursiveASTVisitor<MarkReferencedDecls> Inherited; 7562 7563 MarkReferencedDecls(Sema &S, SourceLocation Loc) : S(S), Loc(Loc) { } 7564 7565 bool VisitTemplateArgument(const TemplateArgument &Arg); 7566 bool VisitRecordType(RecordType *T); 7567 }; 7568} 7569 7570bool MarkReferencedDecls::VisitTemplateArgument(const TemplateArgument &Arg) { 7571 if (Arg.getKind() == TemplateArgument::Declaration) { 7572 S.MarkDeclarationReferenced(Loc, Arg.getAsDecl()); 7573 } 7574 7575 return Inherited::VisitTemplateArgument(Arg); 7576} 7577 7578bool MarkReferencedDecls::VisitRecordType(RecordType *T) { 7579 if (ClassTemplateSpecializationDecl *Spec 7580 = dyn_cast<ClassTemplateSpecializationDecl>(T->getDecl())) { 7581 const TemplateArgumentList &Args = Spec->getTemplateArgs(); 7582 return VisitTemplateArguments(Args.getFlatArgumentList(), 7583 Args.flat_size()); 7584 } 7585 7586 return false; 7587} 7588 7589void Sema::MarkDeclarationsReferencedInType(SourceLocation Loc, QualType T) { 7590 MarkReferencedDecls Marker(*this, Loc); 7591 Marker.Visit(Context.getCanonicalType(T)); 7592} 7593 7594/// \brief Emit a diagnostic that describes an effect on the run-time behavior 7595/// of the program being compiled. 7596/// 7597/// This routine emits the given diagnostic when the code currently being 7598/// type-checked is "potentially evaluated", meaning that there is a 7599/// possibility that the code will actually be executable. Code in sizeof() 7600/// expressions, code used only during overload resolution, etc., are not 7601/// potentially evaluated. This routine will suppress such diagnostics or, 7602/// in the absolutely nutty case of potentially potentially evaluated 7603/// expressions (C++ typeid), queue the diagnostic to potentially emit it 7604/// later. 7605/// 7606/// This routine should be used for all diagnostics that describe the run-time 7607/// behavior of a program, such as passing a non-POD value through an ellipsis. 7608/// Failure to do so will likely result in spurious diagnostics or failures 7609/// during overload resolution or within sizeof/alignof/typeof/typeid. 7610bool Sema::DiagRuntimeBehavior(SourceLocation Loc, 7611 const PartialDiagnostic &PD) { 7612 switch (ExprEvalContexts.back().Context ) { 7613 case Unevaluated: 7614 // The argument will never be evaluated, so don't complain. 7615 break; 7616 7617 case PotentiallyEvaluated: 7618 Diag(Loc, PD); 7619 return true; 7620 7621 case PotentiallyPotentiallyEvaluated: 7622 ExprEvalContexts.back().addDiagnostic(Loc, PD); 7623 break; 7624 } 7625 7626 return false; 7627} 7628 7629bool Sema::CheckCallReturnType(QualType ReturnType, SourceLocation Loc, 7630 CallExpr *CE, FunctionDecl *FD) { 7631 if (ReturnType->isVoidType() || !ReturnType->isIncompleteType()) 7632 return false; 7633 7634 PartialDiagnostic Note = 7635 FD ? PDiag(diag::note_function_with_incomplete_return_type_declared_here) 7636 << FD->getDeclName() : PDiag(); 7637 SourceLocation NoteLoc = FD ? FD->getLocation() : SourceLocation(); 7638 7639 if (RequireCompleteType(Loc, ReturnType, 7640 FD ? 7641 PDiag(diag::err_call_function_incomplete_return) 7642 << CE->getSourceRange() << FD->getDeclName() : 7643 PDiag(diag::err_call_incomplete_return) 7644 << CE->getSourceRange(), 7645 std::make_pair(NoteLoc, Note))) 7646 return true; 7647 7648 return false; 7649} 7650 7651// Diagnose the common s/=/==/ typo. Note that adding parentheses 7652// will prevent this condition from triggering, which is what we want. 7653void Sema::DiagnoseAssignmentAsCondition(Expr *E) { 7654 SourceLocation Loc; 7655 7656 unsigned diagnostic = diag::warn_condition_is_assignment; 7657 7658 if (isa<BinaryOperator>(E)) { 7659 BinaryOperator *Op = cast<BinaryOperator>(E); 7660 if (Op->getOpcode() != BinaryOperator::Assign) 7661 return; 7662 7663 // Greylist some idioms by putting them into a warning subcategory. 7664 if (ObjCMessageExpr *ME 7665 = dyn_cast<ObjCMessageExpr>(Op->getRHS()->IgnoreParenCasts())) { 7666 Selector Sel = ME->getSelector(); 7667 7668 // self = [<foo> init...] 7669 if (isSelfExpr(Op->getLHS()) 7670 && Sel.getIdentifierInfoForSlot(0)->getName().startswith("init")) 7671 diagnostic = diag::warn_condition_is_idiomatic_assignment; 7672 7673 // <foo> = [<bar> nextObject] 7674 else if (Sel.isUnarySelector() && 7675 Sel.getIdentifierInfoForSlot(0)->getName() == "nextObject") 7676 diagnostic = diag::warn_condition_is_idiomatic_assignment; 7677 } 7678 7679 Loc = Op->getOperatorLoc(); 7680 } else if (isa<CXXOperatorCallExpr>(E)) { 7681 CXXOperatorCallExpr *Op = cast<CXXOperatorCallExpr>(E); 7682 if (Op->getOperator() != OO_Equal) 7683 return; 7684 7685 Loc = Op->getOperatorLoc(); 7686 } else { 7687 // Not an assignment. 7688 return; 7689 } 7690 7691 SourceLocation Open = E->getSourceRange().getBegin(); 7692 SourceLocation Close = PP.getLocForEndOfToken(E->getSourceRange().getEnd()); 7693 7694 Diag(Loc, diagnostic) << E->getSourceRange(); 7695 Diag(Loc, diag::note_condition_assign_to_comparison) 7696 << FixItHint::CreateReplacement(Loc, "=="); 7697 Diag(Loc, diag::note_condition_assign_silence) 7698 << FixItHint::CreateInsertion(Open, "(") 7699 << FixItHint::CreateInsertion(Close, ")"); 7700} 7701 7702bool Sema::CheckBooleanCondition(Expr *&E, SourceLocation Loc) { 7703 DiagnoseAssignmentAsCondition(E); 7704 7705 if (!E->isTypeDependent()) { 7706 DefaultFunctionArrayLvalueConversion(E); 7707 7708 QualType T = E->getType(); 7709 7710 if (getLangOptions().CPlusPlus) { 7711 if (CheckCXXBooleanCondition(E)) // C++ 6.4p4 7712 return true; 7713 } else if (!T->isScalarType()) { // C99 6.8.4.1p1 7714 Diag(Loc, diag::err_typecheck_statement_requires_scalar) 7715 << T << E->getSourceRange(); 7716 return true; 7717 } 7718 } 7719 7720 return false; 7721} 7722 7723Sema::OwningExprResult Sema::ActOnBooleanCondition(Scope *S, SourceLocation Loc, 7724 ExprArg SubExpr) { 7725 Expr *Sub = SubExpr.takeAs<Expr>(); 7726 if (!Sub) 7727 return ExprError(); 7728 7729 if (CheckBooleanCondition(Sub, Loc)) { 7730 Sub->Destroy(Context); 7731 return ExprError(); 7732 } 7733 7734 return Owned(Sub); 7735} 7736