SemaExpr.cpp revision 26ed985bf8e3d4859e4a7fec6e4983041c81aa44
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/// Determines whether the given record is "fully-formed" at the given 681/// location, i.e. whether a qualified lookup into it is assured of 682/// getting consistent results already. 683static bool IsFullyFormedScope(Sema &SemaRef, CXXRecordDecl *Record) { 684 if (!Record->hasDefinition()) 685 return false; 686 687 for (CXXRecordDecl::base_class_iterator I = Record->bases_begin(), 688 E = Record->bases_end(); I != E; ++I) { 689 CanQualType BaseT = SemaRef.Context.getCanonicalType((*I).getType()); 690 CanQual<RecordType> BaseRT = BaseT->getAs<RecordType>(); 691 if (!BaseRT) return false; 692 693 CXXRecordDecl *BaseRecord = cast<CXXRecordDecl>(BaseRT->getDecl()); 694 if (!BaseRecord->hasDefinition() || 695 !IsFullyFormedScope(SemaRef, BaseRecord)) 696 return false; 697 } 698 699 return true; 700} 701 702/// Determines whether we can lookup this id-expression now or whether 703/// we have to wait until template instantiation is complete. 704static bool IsDependentIdExpression(Sema &SemaRef, const CXXScopeSpec &SS) { 705 DeclContext *DC = SemaRef.computeDeclContext(SS, false); 706 707 // If the qualifier scope isn't computable, it's definitely dependent. 708 if (!DC) return true; 709 710 // If the qualifier scope doesn't name a record, we can always look into it. 711 if (!isa<CXXRecordDecl>(DC)) return false; 712 713 // We can't look into record types unless they're fully-formed. 714 if (!IsFullyFormedScope(SemaRef, cast<CXXRecordDecl>(DC))) return true; 715 716 return false; 717} 718 719/// Determines if the given class is provably not derived from all of 720/// the prospective base classes. 721static bool IsProvablyNotDerivedFrom(Sema &SemaRef, 722 CXXRecordDecl *Record, 723 const llvm::SmallPtrSet<CXXRecordDecl*, 4> &Bases) { 724 if (Bases.count(Record->getCanonicalDecl())) 725 return false; 726 727 RecordDecl *RD = Record->getDefinition(); 728 if (!RD) return false; 729 Record = cast<CXXRecordDecl>(RD); 730 731 for (CXXRecordDecl::base_class_iterator I = Record->bases_begin(), 732 E = Record->bases_end(); I != E; ++I) { 733 CanQualType BaseT = SemaRef.Context.getCanonicalType((*I).getType()); 734 CanQual<RecordType> BaseRT = BaseT->getAs<RecordType>(); 735 if (!BaseRT) return false; 736 737 CXXRecordDecl *BaseRecord = cast<CXXRecordDecl>(BaseRT->getDecl()); 738 if (!IsProvablyNotDerivedFrom(SemaRef, BaseRecord, Bases)) 739 return false; 740 } 741 742 return true; 743} 744 745enum IMAKind { 746 /// The reference is definitely not an instance member access. 747 IMA_Static, 748 749 /// The reference may be an implicit instance member access. 750 IMA_Mixed, 751 752 /// The reference may be to an instance member, but it is invalid if 753 /// so, because the context is not an instance method. 754 IMA_Mixed_StaticContext, 755 756 /// The reference may be to an instance member, but it is invalid if 757 /// so, because the context is from an unrelated class. 758 IMA_Mixed_Unrelated, 759 760 /// The reference is definitely an implicit instance member access. 761 IMA_Instance, 762 763 /// The reference may be to an unresolved using declaration. 764 IMA_Unresolved, 765 766 /// The reference may be to an unresolved using declaration and the 767 /// context is not an instance method. 768 IMA_Unresolved_StaticContext, 769 770 /// The reference is to a member of an anonymous structure in a 771 /// non-class context. 772 IMA_AnonymousMember, 773 774 /// All possible referrents are instance members and the current 775 /// context is not an instance method. 776 IMA_Error_StaticContext, 777 778 /// All possible referrents are instance members of an unrelated 779 /// class. 780 IMA_Error_Unrelated 781}; 782 783/// The given lookup names class member(s) and is not being used for 784/// an address-of-member expression. Classify the type of access 785/// according to whether it's possible that this reference names an 786/// instance member. This is best-effort; it is okay to 787/// conservatively answer "yes", in which case some errors will simply 788/// not be caught until template-instantiation. 789static IMAKind ClassifyImplicitMemberAccess(Sema &SemaRef, 790 const LookupResult &R) { 791 assert(!R.empty() && (*R.begin())->isCXXClassMember()); 792 793 DeclContext *DC = SemaRef.getFunctionLevelDeclContext(); 794 bool isStaticContext = 795 (!isa<CXXMethodDecl>(DC) || 796 cast<CXXMethodDecl>(DC)->isStatic()); 797 798 if (R.isUnresolvableResult()) 799 return isStaticContext ? IMA_Unresolved_StaticContext : IMA_Unresolved; 800 801 // Collect all the declaring classes of instance members we find. 802 bool hasNonInstance = false; 803 llvm::SmallPtrSet<CXXRecordDecl*, 4> Classes; 804 for (LookupResult::iterator I = R.begin(), E = R.end(); I != E; ++I) { 805 NamedDecl *D = *I; 806 if (D->isCXXInstanceMember()) { 807 CXXRecordDecl *R = cast<CXXRecordDecl>(D->getDeclContext()); 808 809 // If this is a member of an anonymous record, move out to the 810 // innermost non-anonymous struct or union. If there isn't one, 811 // that's a special case. 812 while (R->isAnonymousStructOrUnion()) { 813 R = dyn_cast<CXXRecordDecl>(R->getParent()); 814 if (!R) return IMA_AnonymousMember; 815 } 816 Classes.insert(R->getCanonicalDecl()); 817 } 818 else 819 hasNonInstance = true; 820 } 821 822 // If we didn't find any instance members, it can't be an implicit 823 // member reference. 824 if (Classes.empty()) 825 return IMA_Static; 826 827 // If the current context is not an instance method, it can't be 828 // an implicit member reference. 829 if (isStaticContext) 830 return (hasNonInstance ? IMA_Mixed_StaticContext : IMA_Error_StaticContext); 831 832 // If we can prove that the current context is unrelated to all the 833 // declaring classes, it can't be an implicit member reference (in 834 // which case it's an error if any of those members are selected). 835 if (IsProvablyNotDerivedFrom(SemaRef, 836 cast<CXXMethodDecl>(DC)->getParent(), 837 Classes)) 838 return (hasNonInstance ? IMA_Mixed_Unrelated : IMA_Error_Unrelated); 839 840 return (hasNonInstance ? IMA_Mixed : IMA_Instance); 841} 842 843/// Diagnose a reference to a field with no object available. 844static void DiagnoseInstanceReference(Sema &SemaRef, 845 const CXXScopeSpec &SS, 846 const LookupResult &R) { 847 SourceLocation Loc = R.getNameLoc(); 848 SourceRange Range(Loc); 849 if (SS.isSet()) Range.setBegin(SS.getRange().getBegin()); 850 851 if (R.getAsSingle<FieldDecl>()) { 852 if (CXXMethodDecl *MD = dyn_cast<CXXMethodDecl>(SemaRef.CurContext)) { 853 if (MD->isStatic()) { 854 // "invalid use of member 'x' in static member function" 855 SemaRef.Diag(Loc, diag::err_invalid_member_use_in_static_method) 856 << Range << R.getLookupName(); 857 return; 858 } 859 } 860 861 SemaRef.Diag(Loc, diag::err_invalid_non_static_member_use) 862 << R.getLookupName() << Range; 863 return; 864 } 865 866 SemaRef.Diag(Loc, diag::err_member_call_without_object) << Range; 867} 868 869/// Diagnose an empty lookup. 870/// 871/// \return false if new lookup candidates were found 872bool Sema::DiagnoseEmptyLookup(Scope *S, CXXScopeSpec &SS, LookupResult &R, 873 CorrectTypoContext CTC) { 874 DeclarationName Name = R.getLookupName(); 875 876 unsigned diagnostic = diag::err_undeclared_var_use; 877 unsigned diagnostic_suggest = diag::err_undeclared_var_use_suggest; 878 if (Name.getNameKind() == DeclarationName::CXXOperatorName || 879 Name.getNameKind() == DeclarationName::CXXLiteralOperatorName || 880 Name.getNameKind() == DeclarationName::CXXConversionFunctionName) { 881 diagnostic = diag::err_undeclared_use; 882 diagnostic_suggest = diag::err_undeclared_use_suggest; 883 } 884 885 // If the original lookup was an unqualified lookup, fake an 886 // unqualified lookup. This is useful when (for example) the 887 // original lookup would not have found something because it was a 888 // dependent name. 889 for (DeclContext *DC = SS.isEmpty() ? CurContext : 0; 890 DC; DC = DC->getParent()) { 891 if (isa<CXXRecordDecl>(DC)) { 892 LookupQualifiedName(R, DC); 893 894 if (!R.empty()) { 895 // Don't give errors about ambiguities in this lookup. 896 R.suppressDiagnostics(); 897 898 CXXMethodDecl *CurMethod = dyn_cast<CXXMethodDecl>(CurContext); 899 bool isInstance = CurMethod && 900 CurMethod->isInstance() && 901 DC == CurMethod->getParent(); 902 903 // Give a code modification hint to insert 'this->'. 904 // TODO: fixit for inserting 'Base<T>::' in the other cases. 905 // Actually quite difficult! 906 if (isInstance) { 907 Diag(R.getNameLoc(), diagnostic) << Name 908 << FixItHint::CreateInsertion(R.getNameLoc(), "this->"); 909 910 UnresolvedLookupExpr *ULE = cast<UnresolvedLookupExpr>( 911 CallsUndergoingInstantiation.back()->getCallee()); 912 CXXMethodDecl *DepMethod = cast<CXXMethodDecl>( 913 CurMethod->getInstantiatedFromMemberFunction()); 914 QualType DepThisType = DepMethod->getThisType(Context); 915 CXXThisExpr *DepThis = new (Context) CXXThisExpr(R.getNameLoc(), 916 DepThisType, false); 917 TemplateArgumentListInfo TList; 918 if (ULE->hasExplicitTemplateArgs()) 919 ULE->copyTemplateArgumentsInto(TList); 920 CXXDependentScopeMemberExpr *DepExpr = 921 CXXDependentScopeMemberExpr::Create( 922 Context, DepThis, DepThisType, true, SourceLocation(), 923 ULE->getQualifier(), ULE->getQualifierRange(), NULL, Name, 924 R.getNameLoc(), &TList); 925 CallsUndergoingInstantiation.back()->setCallee(DepExpr); 926 } else { 927 Diag(R.getNameLoc(), diagnostic) << Name; 928 } 929 930 // Do we really want to note all of these? 931 for (LookupResult::iterator I = R.begin(), E = R.end(); I != E; ++I) 932 Diag((*I)->getLocation(), diag::note_dependent_var_use); 933 934 // Tell the callee to try to recover. 935 return false; 936 } 937 } 938 } 939 940 // We didn't find anything, so try to correct for a typo. 941 DeclarationName Corrected; 942 if (S && (Corrected = CorrectTypo(R, S, &SS, 0, false, CTC))) { 943 if (!R.empty()) { 944 if (isa<ValueDecl>(*R.begin()) || isa<FunctionTemplateDecl>(*R.begin())) { 945 if (SS.isEmpty()) 946 Diag(R.getNameLoc(), diagnostic_suggest) << Name << R.getLookupName() 947 << FixItHint::CreateReplacement(R.getNameLoc(), 948 R.getLookupName().getAsString()); 949 else 950 Diag(R.getNameLoc(), diag::err_no_member_suggest) 951 << Name << computeDeclContext(SS, false) << R.getLookupName() 952 << SS.getRange() 953 << FixItHint::CreateReplacement(R.getNameLoc(), 954 R.getLookupName().getAsString()); 955 if (NamedDecl *ND = R.getAsSingle<NamedDecl>()) 956 Diag(ND->getLocation(), diag::note_previous_decl) 957 << ND->getDeclName(); 958 959 // Tell the callee to try to recover. 960 return false; 961 } 962 963 if (isa<TypeDecl>(*R.begin()) || isa<ObjCInterfaceDecl>(*R.begin())) { 964 // FIXME: If we ended up with a typo for a type name or 965 // Objective-C class name, we're in trouble because the parser 966 // is in the wrong place to recover. Suggest the typo 967 // correction, but don't make it a fix-it since we're not going 968 // to recover well anyway. 969 if (SS.isEmpty()) 970 Diag(R.getNameLoc(), diagnostic_suggest) << Name << R.getLookupName(); 971 else 972 Diag(R.getNameLoc(), diag::err_no_member_suggest) 973 << Name << computeDeclContext(SS, false) << R.getLookupName() 974 << SS.getRange(); 975 976 // Don't try to recover; it won't work. 977 return true; 978 } 979 } else { 980 // FIXME: We found a keyword. Suggest it, but don't provide a fix-it 981 // because we aren't able to recover. 982 if (SS.isEmpty()) 983 Diag(R.getNameLoc(), diagnostic_suggest) << Name << Corrected; 984 else 985 Diag(R.getNameLoc(), diag::err_no_member_suggest) 986 << Name << computeDeclContext(SS, false) << Corrected 987 << SS.getRange(); 988 return true; 989 } 990 R.clear(); 991 } 992 993 // Emit a special diagnostic for failed member lookups. 994 // FIXME: computing the declaration context might fail here (?) 995 if (!SS.isEmpty()) { 996 Diag(R.getNameLoc(), diag::err_no_member) 997 << Name << computeDeclContext(SS, false) 998 << SS.getRange(); 999 return true; 1000 } 1001 1002 // Give up, we can't recover. 1003 Diag(R.getNameLoc(), diagnostic) << Name; 1004 return true; 1005} 1006 1007Sema::OwningExprResult Sema::ActOnIdExpression(Scope *S, 1008 CXXScopeSpec &SS, 1009 UnqualifiedId &Id, 1010 bool HasTrailingLParen, 1011 bool isAddressOfOperand) { 1012 assert(!(isAddressOfOperand && HasTrailingLParen) && 1013 "cannot be direct & operand and have a trailing lparen"); 1014 1015 if (SS.isInvalid()) 1016 return ExprError(); 1017 1018 TemplateArgumentListInfo TemplateArgsBuffer; 1019 1020 // Decompose the UnqualifiedId into the following data. 1021 DeclarationName Name; 1022 SourceLocation NameLoc; 1023 const TemplateArgumentListInfo *TemplateArgs; 1024 DecomposeUnqualifiedId(*this, Id, TemplateArgsBuffer, 1025 Name, NameLoc, TemplateArgs); 1026 1027 IdentifierInfo *II = Name.getAsIdentifierInfo(); 1028 1029 // C++ [temp.dep.expr]p3: 1030 // An id-expression is type-dependent if it contains: 1031 // -- an identifier that was declared with a dependent type, 1032 // (note: handled after lookup) 1033 // -- a template-id that is dependent, 1034 // (note: handled in BuildTemplateIdExpr) 1035 // -- a conversion-function-id that specifies a dependent type, 1036 // -- a nested-name-specifier that contains a class-name that 1037 // names a dependent type. 1038 // Determine whether this is a member of an unknown specialization; 1039 // we need to handle these differently. 1040 if ((Name.getNameKind() == DeclarationName::CXXConversionFunctionName && 1041 Name.getCXXNameType()->isDependentType()) || 1042 (SS.isSet() && IsDependentIdExpression(*this, SS))) { 1043 return ActOnDependentIdExpression(SS, Name, NameLoc, 1044 isAddressOfOperand, 1045 TemplateArgs); 1046 } 1047 1048 // Perform the required lookup. 1049 LookupResult R(*this, Name, NameLoc, LookupOrdinaryName); 1050 if (TemplateArgs) { 1051 // Lookup the template name again to correctly establish the context in 1052 // which it was found. This is really unfortunate as we already did the 1053 // lookup to determine that it was a template name in the first place. If 1054 // this becomes a performance hit, we can work harder to preserve those 1055 // results until we get here but it's likely not worth it. 1056 bool MemberOfUnknownSpecialization; 1057 LookupTemplateName(R, S, SS, QualType(), /*EnteringContext=*/false, 1058 MemberOfUnknownSpecialization); 1059 } else { 1060 bool IvarLookupFollowUp = (!SS.isSet() && II && getCurMethodDecl()); 1061 LookupParsedName(R, S, &SS, !IvarLookupFollowUp); 1062 1063 // If this reference is in an Objective-C method, then we need to do 1064 // some special Objective-C lookup, too. 1065 if (IvarLookupFollowUp) { 1066 OwningExprResult E(LookupInObjCMethod(R, S, II, true)); 1067 if (E.isInvalid()) 1068 return ExprError(); 1069 1070 Expr *Ex = E.takeAs<Expr>(); 1071 if (Ex) return Owned(Ex); 1072 } 1073 } 1074 1075 if (R.isAmbiguous()) 1076 return ExprError(); 1077 1078 // Determine whether this name might be a candidate for 1079 // argument-dependent lookup. 1080 bool ADL = UseArgumentDependentLookup(SS, R, HasTrailingLParen); 1081 1082 if (R.empty() && !ADL) { 1083 // Otherwise, this could be an implicitly declared function reference (legal 1084 // in C90, extension in C99, forbidden in C++). 1085 if (HasTrailingLParen && II && !getLangOptions().CPlusPlus) { 1086 NamedDecl *D = ImplicitlyDefineFunction(NameLoc, *II, S); 1087 if (D) R.addDecl(D); 1088 } 1089 1090 // If this name wasn't predeclared and if this is not a function 1091 // call, diagnose the problem. 1092 if (R.empty()) { 1093 if (DiagnoseEmptyLookup(S, SS, R, CTC_Unknown)) 1094 return ExprError(); 1095 1096 assert(!R.empty() && 1097 "DiagnoseEmptyLookup returned false but added no results"); 1098 1099 // If we found an Objective-C instance variable, let 1100 // LookupInObjCMethod build the appropriate expression to 1101 // reference the ivar. 1102 if (ObjCIvarDecl *Ivar = R.getAsSingle<ObjCIvarDecl>()) { 1103 R.clear(); 1104 OwningExprResult E(LookupInObjCMethod(R, S, Ivar->getIdentifier())); 1105 assert(E.isInvalid() || E.get()); 1106 return move(E); 1107 } 1108 } 1109 } 1110 1111 // This is guaranteed from this point on. 1112 assert(!R.empty() || ADL); 1113 1114 if (VarDecl *Var = R.getAsSingle<VarDecl>()) { 1115 // Warn about constructs like: 1116 // if (void *X = foo()) { ... } else { X }. 1117 // In the else block, the pointer is always false. 1118 if (Var->isDeclaredInCondition() && Var->getType()->isScalarType()) { 1119 Scope *CheckS = S; 1120 while (CheckS && CheckS->getControlParent()) { 1121 if ((CheckS->getFlags() & Scope::ElseScope) && 1122 CheckS->getControlParent()->isDeclScope(DeclPtrTy::make(Var))) { 1123 ExprError(Diag(NameLoc, diag::warn_value_always_zero) 1124 << Var->getDeclName() 1125 << (Var->getType()->isPointerType() ? 2 : 1126 Var->getType()->isBooleanType() ? 1 : 0)); 1127 break; 1128 } 1129 1130 // Move to the parent of this scope. 1131 CheckS = CheckS->getParent(); 1132 } 1133 } 1134 } else if (FunctionDecl *Func = R.getAsSingle<FunctionDecl>()) { 1135 if (!getLangOptions().CPlusPlus && !Func->hasPrototype()) { 1136 // C99 DR 316 says that, if a function type comes from a 1137 // function definition (without a prototype), that type is only 1138 // used for checking compatibility. Therefore, when referencing 1139 // the function, we pretend that we don't have the full function 1140 // type. 1141 if (DiagnoseUseOfDecl(Func, NameLoc)) 1142 return ExprError(); 1143 1144 QualType T = Func->getType(); 1145 QualType NoProtoType = T; 1146 if (const FunctionProtoType *Proto = T->getAs<FunctionProtoType>()) 1147 NoProtoType = Context.getFunctionNoProtoType(Proto->getResultType(), 1148 Proto->getExtInfo()); 1149 return BuildDeclRefExpr(Func, NoProtoType, NameLoc, &SS); 1150 } 1151 } 1152 1153 // Check whether this might be a C++ implicit instance member access. 1154 // C++ [expr.prim.general]p6: 1155 // Within the definition of a non-static member function, an 1156 // identifier that names a non-static member is transformed to a 1157 // class member access expression. 1158 // But note that &SomeClass::foo is grammatically distinct, even 1159 // though we don't parse it that way. 1160 if (!R.empty() && (*R.begin())->isCXXClassMember()) { 1161 bool isAbstractMemberPointer = (isAddressOfOperand && !SS.isEmpty()); 1162 if (!isAbstractMemberPointer) 1163 return BuildPossibleImplicitMemberExpr(SS, R, TemplateArgs); 1164 } 1165 1166 if (TemplateArgs) 1167 return BuildTemplateIdExpr(SS, R, ADL, *TemplateArgs); 1168 1169 return BuildDeclarationNameExpr(SS, R, ADL); 1170} 1171 1172/// Builds an expression which might be an implicit member expression. 1173Sema::OwningExprResult 1174Sema::BuildPossibleImplicitMemberExpr(const CXXScopeSpec &SS, 1175 LookupResult &R, 1176 const TemplateArgumentListInfo *TemplateArgs) { 1177 switch (ClassifyImplicitMemberAccess(*this, R)) { 1178 case IMA_Instance: 1179 return BuildImplicitMemberExpr(SS, R, TemplateArgs, true); 1180 1181 case IMA_AnonymousMember: 1182 assert(R.isSingleResult()); 1183 return BuildAnonymousStructUnionMemberReference(R.getNameLoc(), 1184 R.getAsSingle<FieldDecl>()); 1185 1186 case IMA_Mixed: 1187 case IMA_Mixed_Unrelated: 1188 case IMA_Unresolved: 1189 return BuildImplicitMemberExpr(SS, R, TemplateArgs, false); 1190 1191 case IMA_Static: 1192 case IMA_Mixed_StaticContext: 1193 case IMA_Unresolved_StaticContext: 1194 if (TemplateArgs) 1195 return BuildTemplateIdExpr(SS, R, false, *TemplateArgs); 1196 return BuildDeclarationNameExpr(SS, R, false); 1197 1198 case IMA_Error_StaticContext: 1199 case IMA_Error_Unrelated: 1200 DiagnoseInstanceReference(*this, SS, R); 1201 return ExprError(); 1202 } 1203 1204 llvm_unreachable("unexpected instance member access kind"); 1205 return ExprError(); 1206} 1207 1208/// BuildQualifiedDeclarationNameExpr - Build a C++ qualified 1209/// declaration name, generally during template instantiation. 1210/// There's a large number of things which don't need to be done along 1211/// this path. 1212Sema::OwningExprResult 1213Sema::BuildQualifiedDeclarationNameExpr(CXXScopeSpec &SS, 1214 DeclarationName Name, 1215 SourceLocation NameLoc) { 1216 DeclContext *DC; 1217 if (!(DC = computeDeclContext(SS, false)) || DC->isDependentContext()) 1218 return BuildDependentDeclRefExpr(SS, Name, NameLoc, 0); 1219 1220 if (RequireCompleteDeclContext(SS, DC)) 1221 return ExprError(); 1222 1223 LookupResult R(*this, Name, NameLoc, LookupOrdinaryName); 1224 LookupQualifiedName(R, DC); 1225 1226 if (R.isAmbiguous()) 1227 return ExprError(); 1228 1229 if (R.empty()) { 1230 Diag(NameLoc, diag::err_no_member) << Name << DC << SS.getRange(); 1231 return ExprError(); 1232 } 1233 1234 return BuildDeclarationNameExpr(SS, R, /*ADL*/ false); 1235} 1236 1237/// LookupInObjCMethod - The parser has read a name in, and Sema has 1238/// detected that we're currently inside an ObjC method. Perform some 1239/// additional lookup. 1240/// 1241/// Ideally, most of this would be done by lookup, but there's 1242/// actually quite a lot of extra work involved. 1243/// 1244/// Returns a null sentinel to indicate trivial success. 1245Sema::OwningExprResult 1246Sema::LookupInObjCMethod(LookupResult &Lookup, Scope *S, 1247 IdentifierInfo *II, bool AllowBuiltinCreation) { 1248 SourceLocation Loc = Lookup.getNameLoc(); 1249 ObjCMethodDecl *CurMethod = getCurMethodDecl(); 1250 1251 // There are two cases to handle here. 1) scoped lookup could have failed, 1252 // in which case we should look for an ivar. 2) scoped lookup could have 1253 // found a decl, but that decl is outside the current instance method (i.e. 1254 // a global variable). In these two cases, we do a lookup for an ivar with 1255 // this name, if the lookup sucedes, we replace it our current decl. 1256 1257 // If we're in a class method, we don't normally want to look for 1258 // ivars. But if we don't find anything else, and there's an 1259 // ivar, that's an error. 1260 bool IsClassMethod = CurMethod->isClassMethod(); 1261 1262 bool LookForIvars; 1263 if (Lookup.empty()) 1264 LookForIvars = true; 1265 else if (IsClassMethod) 1266 LookForIvars = false; 1267 else 1268 LookForIvars = (Lookup.isSingleResult() && 1269 Lookup.getFoundDecl()->isDefinedOutsideFunctionOrMethod()); 1270 ObjCInterfaceDecl *IFace = 0; 1271 if (LookForIvars) { 1272 IFace = CurMethod->getClassInterface(); 1273 ObjCInterfaceDecl *ClassDeclared; 1274 if (ObjCIvarDecl *IV = IFace->lookupInstanceVariable(II, ClassDeclared)) { 1275 // Diagnose using an ivar in a class method. 1276 if (IsClassMethod) 1277 return ExprError(Diag(Loc, diag::error_ivar_use_in_class_method) 1278 << IV->getDeclName()); 1279 1280 // If we're referencing an invalid decl, just return this as a silent 1281 // error node. The error diagnostic was already emitted on the decl. 1282 if (IV->isInvalidDecl()) 1283 return ExprError(); 1284 1285 // Check if referencing a field with __attribute__((deprecated)). 1286 if (DiagnoseUseOfDecl(IV, Loc)) 1287 return ExprError(); 1288 1289 // Diagnose the use of an ivar outside of the declaring class. 1290 if (IV->getAccessControl() == ObjCIvarDecl::Private && 1291 ClassDeclared != IFace) 1292 Diag(Loc, diag::error_private_ivar_access) << IV->getDeclName(); 1293 1294 // FIXME: This should use a new expr for a direct reference, don't 1295 // turn this into Self->ivar, just return a BareIVarExpr or something. 1296 IdentifierInfo &II = Context.Idents.get("self"); 1297 UnqualifiedId SelfName; 1298 SelfName.setIdentifier(&II, SourceLocation()); 1299 CXXScopeSpec SelfScopeSpec; 1300 OwningExprResult SelfExpr = ActOnIdExpression(S, SelfScopeSpec, 1301 SelfName, false, false); 1302 MarkDeclarationReferenced(Loc, IV); 1303 return Owned(new (Context) 1304 ObjCIvarRefExpr(IV, IV->getType(), Loc, 1305 SelfExpr.takeAs<Expr>(), true, true)); 1306 } 1307 } else if (CurMethod->isInstanceMethod()) { 1308 // We should warn if a local variable hides an ivar. 1309 ObjCInterfaceDecl *IFace = CurMethod->getClassInterface(); 1310 ObjCInterfaceDecl *ClassDeclared; 1311 if (ObjCIvarDecl *IV = IFace->lookupInstanceVariable(II, ClassDeclared)) { 1312 if (IV->getAccessControl() != ObjCIvarDecl::Private || 1313 IFace == ClassDeclared) 1314 Diag(Loc, diag::warn_ivar_use_hidden) << IV->getDeclName(); 1315 } 1316 } 1317 1318 if (Lookup.empty() && II && AllowBuiltinCreation) { 1319 // FIXME. Consolidate this with similar code in LookupName. 1320 if (unsigned BuiltinID = II->getBuiltinID()) { 1321 if (!(getLangOptions().CPlusPlus && 1322 Context.BuiltinInfo.isPredefinedLibFunction(BuiltinID))) { 1323 NamedDecl *D = LazilyCreateBuiltin((IdentifierInfo *)II, BuiltinID, 1324 S, Lookup.isForRedeclaration(), 1325 Lookup.getNameLoc()); 1326 if (D) Lookup.addDecl(D); 1327 } 1328 } 1329 } 1330 // Sentinel value saying that we didn't do anything special. 1331 return Owned((Expr*) 0); 1332} 1333 1334/// \brief Cast a base object to a member's actual type. 1335/// 1336/// Logically this happens in three phases: 1337/// 1338/// * First we cast from the base type to the naming class. 1339/// The naming class is the class into which we were looking 1340/// when we found the member; it's the qualifier type if a 1341/// qualifier was provided, and otherwise it's the base type. 1342/// 1343/// * Next we cast from the naming class to the declaring class. 1344/// If the member we found was brought into a class's scope by 1345/// a using declaration, this is that class; otherwise it's 1346/// the class declaring the member. 1347/// 1348/// * Finally we cast from the declaring class to the "true" 1349/// declaring class of the member. This conversion does not 1350/// obey access control. 1351bool 1352Sema::PerformObjectMemberConversion(Expr *&From, 1353 NestedNameSpecifier *Qualifier, 1354 NamedDecl *FoundDecl, 1355 NamedDecl *Member) { 1356 CXXRecordDecl *RD = dyn_cast<CXXRecordDecl>(Member->getDeclContext()); 1357 if (!RD) 1358 return false; 1359 1360 QualType DestRecordType; 1361 QualType DestType; 1362 QualType FromRecordType; 1363 QualType FromType = From->getType(); 1364 bool PointerConversions = false; 1365 if (isa<FieldDecl>(Member)) { 1366 DestRecordType = Context.getCanonicalType(Context.getTypeDeclType(RD)); 1367 1368 if (FromType->getAs<PointerType>()) { 1369 DestType = Context.getPointerType(DestRecordType); 1370 FromRecordType = FromType->getPointeeType(); 1371 PointerConversions = true; 1372 } else { 1373 DestType = DestRecordType; 1374 FromRecordType = FromType; 1375 } 1376 } else if (CXXMethodDecl *Method = dyn_cast<CXXMethodDecl>(Member)) { 1377 if (Method->isStatic()) 1378 return false; 1379 1380 DestType = Method->getThisType(Context); 1381 DestRecordType = DestType->getPointeeType(); 1382 1383 if (FromType->getAs<PointerType>()) { 1384 FromRecordType = FromType->getPointeeType(); 1385 PointerConversions = true; 1386 } else { 1387 FromRecordType = FromType; 1388 DestType = DestRecordType; 1389 } 1390 } else { 1391 // No conversion necessary. 1392 return false; 1393 } 1394 1395 if (DestType->isDependentType() || FromType->isDependentType()) 1396 return false; 1397 1398 // If the unqualified types are the same, no conversion is necessary. 1399 if (Context.hasSameUnqualifiedType(FromRecordType, DestRecordType)) 1400 return false; 1401 1402 SourceRange FromRange = From->getSourceRange(); 1403 SourceLocation FromLoc = FromRange.getBegin(); 1404 1405 bool isLvalue 1406 = (From->isLvalue(Context) == Expr::LV_Valid) && !PointerConversions; 1407 1408 // C++ [class.member.lookup]p8: 1409 // [...] Ambiguities can often be resolved by qualifying a name with its 1410 // class name. 1411 // 1412 // If the member was a qualified name and the qualified referred to a 1413 // specific base subobject type, we'll cast to that intermediate type 1414 // first and then to the object in which the member is declared. That allows 1415 // one to resolve ambiguities in, e.g., a diamond-shaped hierarchy such as: 1416 // 1417 // class Base { public: int x; }; 1418 // class Derived1 : public Base { }; 1419 // class Derived2 : public Base { }; 1420 // class VeryDerived : public Derived1, public Derived2 { void f(); }; 1421 // 1422 // void VeryDerived::f() { 1423 // x = 17; // error: ambiguous base subobjects 1424 // Derived1::x = 17; // okay, pick the Base subobject of Derived1 1425 // } 1426 if (Qualifier) { 1427 QualType QType = QualType(Qualifier->getAsType(), 0); 1428 assert(!QType.isNull() && "lookup done with dependent qualifier?"); 1429 assert(QType->isRecordType() && "lookup done with non-record type"); 1430 1431 QualType QRecordType = QualType(QType->getAs<RecordType>(), 0); 1432 1433 // In C++98, the qualifier type doesn't actually have to be a base 1434 // type of the object type, in which case we just ignore it. 1435 // Otherwise build the appropriate casts. 1436 if (IsDerivedFrom(FromRecordType, QRecordType)) { 1437 CXXBaseSpecifierArray BasePath; 1438 if (CheckDerivedToBaseConversion(FromRecordType, QRecordType, 1439 FromLoc, FromRange, &BasePath)) 1440 return true; 1441 1442 if (PointerConversions) 1443 QType = Context.getPointerType(QType); 1444 ImpCastExprToType(From, QType, CastExpr::CK_UncheckedDerivedToBase, 1445 isLvalue, BasePath); 1446 1447 FromType = QType; 1448 FromRecordType = QRecordType; 1449 1450 // If the qualifier type was the same as the destination type, 1451 // we're done. 1452 if (Context.hasSameUnqualifiedType(FromRecordType, DestRecordType)) 1453 return false; 1454 } 1455 } 1456 1457 bool IgnoreAccess = false; 1458 1459 // If we actually found the member through a using declaration, cast 1460 // down to the using declaration's type. 1461 // 1462 // Pointer equality is fine here because only one declaration of a 1463 // class ever has member declarations. 1464 if (FoundDecl->getDeclContext() != Member->getDeclContext()) { 1465 assert(isa<UsingShadowDecl>(FoundDecl)); 1466 QualType URecordType = Context.getTypeDeclType( 1467 cast<CXXRecordDecl>(FoundDecl->getDeclContext())); 1468 1469 // We only need to do this if the naming-class to declaring-class 1470 // conversion is non-trivial. 1471 if (!Context.hasSameUnqualifiedType(FromRecordType, URecordType)) { 1472 assert(IsDerivedFrom(FromRecordType, URecordType)); 1473 CXXBaseSpecifierArray BasePath; 1474 if (CheckDerivedToBaseConversion(FromRecordType, URecordType, 1475 FromLoc, FromRange, &BasePath)) 1476 return true; 1477 1478 QualType UType = URecordType; 1479 if (PointerConversions) 1480 UType = Context.getPointerType(UType); 1481 ImpCastExprToType(From, UType, CastExpr::CK_UncheckedDerivedToBase, 1482 isLvalue, BasePath); 1483 FromType = UType; 1484 FromRecordType = URecordType; 1485 } 1486 1487 // We don't do access control for the conversion from the 1488 // declaring class to the true declaring class. 1489 IgnoreAccess = true; 1490 } 1491 1492 CXXBaseSpecifierArray BasePath; 1493 if (CheckDerivedToBaseConversion(FromRecordType, DestRecordType, 1494 FromLoc, FromRange, &BasePath, 1495 IgnoreAccess)) 1496 return true; 1497 1498 ImpCastExprToType(From, DestType, CastExpr::CK_UncheckedDerivedToBase, 1499 isLvalue, BasePath); 1500 return false; 1501} 1502 1503/// \brief Build a MemberExpr AST node. 1504static MemberExpr *BuildMemberExpr(ASTContext &C, Expr *Base, bool isArrow, 1505 const CXXScopeSpec &SS, ValueDecl *Member, 1506 DeclAccessPair FoundDecl, 1507 SourceLocation Loc, QualType Ty, 1508 const TemplateArgumentListInfo *TemplateArgs = 0) { 1509 NestedNameSpecifier *Qualifier = 0; 1510 SourceRange QualifierRange; 1511 if (SS.isSet()) { 1512 Qualifier = (NestedNameSpecifier *) SS.getScopeRep(); 1513 QualifierRange = SS.getRange(); 1514 } 1515 1516 return MemberExpr::Create(C, Base, isArrow, Qualifier, QualifierRange, 1517 Member, FoundDecl, Loc, TemplateArgs, Ty); 1518} 1519 1520/// Builds an implicit member access expression. The current context 1521/// is known to be an instance method, and the given unqualified lookup 1522/// set is known to contain only instance members, at least one of which 1523/// is from an appropriate type. 1524Sema::OwningExprResult 1525Sema::BuildImplicitMemberExpr(const CXXScopeSpec &SS, 1526 LookupResult &R, 1527 const TemplateArgumentListInfo *TemplateArgs, 1528 bool IsKnownInstance) { 1529 assert(!R.empty() && !R.isAmbiguous()); 1530 1531 SourceLocation Loc = R.getNameLoc(); 1532 1533 // We may have found a field within an anonymous union or struct 1534 // (C++ [class.union]). 1535 // FIXME: This needs to happen post-isImplicitMemberReference? 1536 // FIXME: template-ids inside anonymous structs? 1537 if (FieldDecl *FD = R.getAsSingle<FieldDecl>()) 1538 if (cast<RecordDecl>(FD->getDeclContext())->isAnonymousStructOrUnion()) 1539 return BuildAnonymousStructUnionMemberReference(Loc, FD); 1540 1541 // If this is known to be an instance access, go ahead and build a 1542 // 'this' expression now. 1543 DeclContext *DC = getFunctionLevelDeclContext(); 1544 QualType ThisType = cast<CXXMethodDecl>(DC)->getThisType(Context); 1545 Expr *This = 0; // null signifies implicit access 1546 if (IsKnownInstance) { 1547 SourceLocation Loc = R.getNameLoc(); 1548 if (SS.getRange().isValid()) 1549 Loc = SS.getRange().getBegin(); 1550 This = new (Context) CXXThisExpr(Loc, ThisType, /*isImplicit=*/true); 1551 } 1552 1553 return BuildMemberReferenceExpr(ExprArg(*this, This), ThisType, 1554 /*OpLoc*/ SourceLocation(), 1555 /*IsArrow*/ true, 1556 SS, 1557 /*FirstQualifierInScope*/ 0, 1558 R, TemplateArgs); 1559} 1560 1561bool Sema::UseArgumentDependentLookup(const CXXScopeSpec &SS, 1562 const LookupResult &R, 1563 bool HasTrailingLParen) { 1564 // Only when used directly as the postfix-expression of a call. 1565 if (!HasTrailingLParen) 1566 return false; 1567 1568 // Never if a scope specifier was provided. 1569 if (SS.isSet()) 1570 return false; 1571 1572 // Only in C++ or ObjC++. 1573 if (!getLangOptions().CPlusPlus) 1574 return false; 1575 1576 // Turn off ADL when we find certain kinds of declarations during 1577 // normal lookup: 1578 for (LookupResult::iterator I = R.begin(), E = R.end(); I != E; ++I) { 1579 NamedDecl *D = *I; 1580 1581 // C++0x [basic.lookup.argdep]p3: 1582 // -- a declaration of a class member 1583 // Since using decls preserve this property, we check this on the 1584 // original decl. 1585 if (D->isCXXClassMember()) 1586 return false; 1587 1588 // C++0x [basic.lookup.argdep]p3: 1589 // -- a block-scope function declaration that is not a 1590 // using-declaration 1591 // NOTE: we also trigger this for function templates (in fact, we 1592 // don't check the decl type at all, since all other decl types 1593 // turn off ADL anyway). 1594 if (isa<UsingShadowDecl>(D)) 1595 D = cast<UsingShadowDecl>(D)->getTargetDecl(); 1596 else if (D->getDeclContext()->isFunctionOrMethod()) 1597 return false; 1598 1599 // C++0x [basic.lookup.argdep]p3: 1600 // -- a declaration that is neither a function or a function 1601 // template 1602 // And also for builtin functions. 1603 if (isa<FunctionDecl>(D)) { 1604 FunctionDecl *FDecl = cast<FunctionDecl>(D); 1605 1606 // But also builtin functions. 1607 if (FDecl->getBuiltinID() && FDecl->isImplicit()) 1608 return false; 1609 } else if (!isa<FunctionTemplateDecl>(D)) 1610 return false; 1611 } 1612 1613 return true; 1614} 1615 1616 1617/// Diagnoses obvious problems with the use of the given declaration 1618/// as an expression. This is only actually called for lookups that 1619/// were not overloaded, and it doesn't promise that the declaration 1620/// will in fact be used. 1621static bool CheckDeclInExpr(Sema &S, SourceLocation Loc, NamedDecl *D) { 1622 if (isa<TypedefDecl>(D)) { 1623 S.Diag(Loc, diag::err_unexpected_typedef) << D->getDeclName(); 1624 return true; 1625 } 1626 1627 if (isa<ObjCInterfaceDecl>(D)) { 1628 S.Diag(Loc, diag::err_unexpected_interface) << D->getDeclName(); 1629 return true; 1630 } 1631 1632 if (isa<NamespaceDecl>(D)) { 1633 S.Diag(Loc, diag::err_unexpected_namespace) << D->getDeclName(); 1634 return true; 1635 } 1636 1637 return false; 1638} 1639 1640Sema::OwningExprResult 1641Sema::BuildDeclarationNameExpr(const CXXScopeSpec &SS, 1642 LookupResult &R, 1643 bool NeedsADL) { 1644 // If this is a single, fully-resolved result and we don't need ADL, 1645 // just build an ordinary singleton decl ref. 1646 if (!NeedsADL && R.isSingleResult() && !R.getAsSingle<FunctionTemplateDecl>()) 1647 return BuildDeclarationNameExpr(SS, R.getNameLoc(), R.getFoundDecl()); 1648 1649 // We only need to check the declaration if there's exactly one 1650 // result, because in the overloaded case the results can only be 1651 // functions and function templates. 1652 if (R.isSingleResult() && 1653 CheckDeclInExpr(*this, R.getNameLoc(), R.getFoundDecl())) 1654 return ExprError(); 1655 1656 // Otherwise, just build an unresolved lookup expression. Suppress 1657 // any lookup-related diagnostics; we'll hash these out later, when 1658 // we've picked a target. 1659 R.suppressDiagnostics(); 1660 1661 bool Dependent 1662 = UnresolvedLookupExpr::ComputeDependence(R.begin(), R.end(), 0); 1663 UnresolvedLookupExpr *ULE 1664 = UnresolvedLookupExpr::Create(Context, Dependent, R.getNamingClass(), 1665 (NestedNameSpecifier*) SS.getScopeRep(), 1666 SS.getRange(), 1667 R.getLookupName(), R.getNameLoc(), 1668 NeedsADL, R.isOverloadedResult(), 1669 R.begin(), R.end()); 1670 1671 return Owned(ULE); 1672} 1673 1674 1675/// \brief Complete semantic analysis for a reference to the given declaration. 1676Sema::OwningExprResult 1677Sema::BuildDeclarationNameExpr(const CXXScopeSpec &SS, 1678 SourceLocation Loc, NamedDecl *D) { 1679 assert(D && "Cannot refer to a NULL declaration"); 1680 assert(!isa<FunctionTemplateDecl>(D) && 1681 "Cannot refer unambiguously to a function template"); 1682 1683 if (CheckDeclInExpr(*this, Loc, D)) 1684 return ExprError(); 1685 1686 if (TemplateDecl *Template = dyn_cast<TemplateDecl>(D)) { 1687 // Specifically diagnose references to class templates that are missing 1688 // a template argument list. 1689 Diag(Loc, diag::err_template_decl_ref) 1690 << Template << SS.getRange(); 1691 Diag(Template->getLocation(), diag::note_template_decl_here); 1692 return ExprError(); 1693 } 1694 1695 // Make sure that we're referring to a value. 1696 ValueDecl *VD = dyn_cast<ValueDecl>(D); 1697 if (!VD) { 1698 Diag(Loc, diag::err_ref_non_value) 1699 << D << SS.getRange(); 1700 Diag(D->getLocation(), diag::note_declared_at); 1701 return ExprError(); 1702 } 1703 1704 // Check whether this declaration can be used. Note that we suppress 1705 // this check when we're going to perform argument-dependent lookup 1706 // on this function name, because this might not be the function 1707 // that overload resolution actually selects. 1708 if (DiagnoseUseOfDecl(VD, Loc)) 1709 return ExprError(); 1710 1711 // Only create DeclRefExpr's for valid Decl's. 1712 if (VD->isInvalidDecl()) 1713 return ExprError(); 1714 1715 // If the identifier reference is inside a block, and it refers to a value 1716 // that is outside the block, create a BlockDeclRefExpr instead of a 1717 // DeclRefExpr. This ensures the value is treated as a copy-in snapshot when 1718 // the block is formed. 1719 // 1720 // We do not do this for things like enum constants, global variables, etc, 1721 // as they do not get snapshotted. 1722 // 1723 if (getCurBlock() && 1724 ShouldSnapshotBlockValueReference(*this, getCurBlock(), VD)) { 1725 if (VD->getType().getTypePtr()->isVariablyModifiedType()) { 1726 Diag(Loc, diag::err_ref_vm_type); 1727 Diag(D->getLocation(), diag::note_declared_at); 1728 return ExprError(); 1729 } 1730 1731 if (VD->getType()->isArrayType()) { 1732 Diag(Loc, diag::err_ref_array_type); 1733 Diag(D->getLocation(), diag::note_declared_at); 1734 return ExprError(); 1735 } 1736 1737 MarkDeclarationReferenced(Loc, VD); 1738 QualType ExprTy = VD->getType().getNonReferenceType(); 1739 // The BlocksAttr indicates the variable is bound by-reference. 1740 if (VD->getAttr<BlocksAttr>()) 1741 return Owned(new (Context) BlockDeclRefExpr(VD, ExprTy, Loc, true)); 1742 // This is to record that a 'const' was actually synthesize and added. 1743 bool constAdded = !ExprTy.isConstQualified(); 1744 // Variable will be bound by-copy, make it const within the closure. 1745 1746 ExprTy.addConst(); 1747 BlockDeclRefExpr *BDRE = new (Context) BlockDeclRefExpr(VD, 1748 ExprTy, Loc, false, 1749 constAdded); 1750 QualType T = VD->getType(); 1751 if (getLangOptions().CPlusPlus) { 1752 if (!T->isDependentType() && !T->isReferenceType()) { 1753 Expr *E = new (Context) 1754 DeclRefExpr(const_cast<ValueDecl*>(BDRE->getDecl()), T, 1755 SourceLocation()); 1756 1757 OwningExprResult Res = PerformCopyInitialization( 1758 InitializedEntity::InitializeBlock(VD->getLocation(), 1759 T, false), 1760 SourceLocation(), 1761 Owned(E)); 1762 if (!Res.isInvalid()) { 1763 Res = MaybeCreateCXXExprWithTemporaries(move(Res)); 1764 Expr *Init = Res.takeAs<Expr>(); 1765 BDRE->setCopyConstructorExpr(Init); 1766 } 1767 } 1768 else if (T->isDependentType()) 1769 BDRE->setTypeDependent(true); 1770 } 1771 return Owned(BDRE); 1772 } 1773 // If this reference is not in a block or if the referenced variable is 1774 // within the block, create a normal DeclRefExpr. 1775 1776 return BuildDeclRefExpr(VD, VD->getType().getNonReferenceType(), Loc, &SS); 1777} 1778 1779Sema::OwningExprResult Sema::ActOnPredefinedExpr(SourceLocation Loc, 1780 tok::TokenKind Kind) { 1781 PredefinedExpr::IdentType IT; 1782 1783 switch (Kind) { 1784 default: assert(0 && "Unknown simple primary expr!"); 1785 case tok::kw___func__: IT = PredefinedExpr::Func; break; // [C99 6.4.2.2] 1786 case tok::kw___FUNCTION__: IT = PredefinedExpr::Function; break; 1787 case tok::kw___PRETTY_FUNCTION__: IT = PredefinedExpr::PrettyFunction; break; 1788 } 1789 1790 // Pre-defined identifiers are of type char[x], where x is the length of the 1791 // string. 1792 1793 Decl *currentDecl = getCurFunctionOrMethodDecl(); 1794 if (!currentDecl) { 1795 Diag(Loc, diag::ext_predef_outside_function); 1796 currentDecl = Context.getTranslationUnitDecl(); 1797 } 1798 1799 QualType ResTy; 1800 if (cast<DeclContext>(currentDecl)->isDependentContext()) { 1801 ResTy = Context.DependentTy; 1802 } else { 1803 unsigned Length = PredefinedExpr::ComputeName(IT, currentDecl).length(); 1804 1805 llvm::APInt LengthI(32, Length + 1); 1806 ResTy = Context.CharTy.withConst(); 1807 ResTy = Context.getConstantArrayType(ResTy, LengthI, ArrayType::Normal, 0); 1808 } 1809 return Owned(new (Context) PredefinedExpr(Loc, ResTy, IT)); 1810} 1811 1812Sema::OwningExprResult Sema::ActOnCharacterConstant(const Token &Tok) { 1813 llvm::SmallString<16> CharBuffer; 1814 bool Invalid = false; 1815 llvm::StringRef ThisTok = PP.getSpelling(Tok, CharBuffer, &Invalid); 1816 if (Invalid) 1817 return ExprError(); 1818 1819 CharLiteralParser Literal(ThisTok.begin(), ThisTok.end(), Tok.getLocation(), 1820 PP); 1821 if (Literal.hadError()) 1822 return ExprError(); 1823 1824 QualType Ty; 1825 if (!getLangOptions().CPlusPlus) 1826 Ty = Context.IntTy; // 'x' and L'x' -> int in C. 1827 else if (Literal.isWide()) 1828 Ty = Context.WCharTy; // L'x' -> wchar_t in C++. 1829 else if (Literal.isMultiChar()) 1830 Ty = Context.IntTy; // 'wxyz' -> int in C++. 1831 else 1832 Ty = Context.CharTy; // 'x' -> char in C++ 1833 1834 return Owned(new (Context) CharacterLiteral(Literal.getValue(), 1835 Literal.isWide(), 1836 Ty, Tok.getLocation())); 1837} 1838 1839Action::OwningExprResult Sema::ActOnNumericConstant(const Token &Tok) { 1840 // Fast path for a single digit (which is quite common). A single digit 1841 // cannot have a trigraph, escaped newline, radix prefix, or type suffix. 1842 if (Tok.getLength() == 1) { 1843 const char Val = PP.getSpellingOfSingleCharacterNumericConstant(Tok); 1844 unsigned IntSize = Context.Target.getIntWidth(); 1845 return Owned(new (Context) IntegerLiteral(llvm::APInt(IntSize, Val-'0'), 1846 Context.IntTy, Tok.getLocation())); 1847 } 1848 1849 llvm::SmallString<512> IntegerBuffer; 1850 // Add padding so that NumericLiteralParser can overread by one character. 1851 IntegerBuffer.resize(Tok.getLength()+1); 1852 const char *ThisTokBegin = &IntegerBuffer[0]; 1853 1854 // Get the spelling of the token, which eliminates trigraphs, etc. 1855 bool Invalid = false; 1856 unsigned ActualLength = PP.getSpelling(Tok, ThisTokBegin, &Invalid); 1857 if (Invalid) 1858 return ExprError(); 1859 1860 NumericLiteralParser Literal(ThisTokBegin, ThisTokBegin+ActualLength, 1861 Tok.getLocation(), PP); 1862 if (Literal.hadError) 1863 return ExprError(); 1864 1865 Expr *Res; 1866 1867 if (Literal.isFloatingLiteral()) { 1868 QualType Ty; 1869 if (Literal.isFloat) 1870 Ty = Context.FloatTy; 1871 else if (!Literal.isLong) 1872 Ty = Context.DoubleTy; 1873 else 1874 Ty = Context.LongDoubleTy; 1875 1876 const llvm::fltSemantics &Format = Context.getFloatTypeSemantics(Ty); 1877 1878 using llvm::APFloat; 1879 APFloat Val(Format); 1880 1881 APFloat::opStatus result = Literal.GetFloatValue(Val); 1882 1883 // Overflow is always an error, but underflow is only an error if 1884 // we underflowed to zero (APFloat reports denormals as underflow). 1885 if ((result & APFloat::opOverflow) || 1886 ((result & APFloat::opUnderflow) && Val.isZero())) { 1887 unsigned diagnostic; 1888 llvm::SmallString<20> buffer; 1889 if (result & APFloat::opOverflow) { 1890 diagnostic = diag::warn_float_overflow; 1891 APFloat::getLargest(Format).toString(buffer); 1892 } else { 1893 diagnostic = diag::warn_float_underflow; 1894 APFloat::getSmallest(Format).toString(buffer); 1895 } 1896 1897 Diag(Tok.getLocation(), diagnostic) 1898 << Ty 1899 << llvm::StringRef(buffer.data(), buffer.size()); 1900 } 1901 1902 bool isExact = (result == APFloat::opOK); 1903 Res = new (Context) FloatingLiteral(Val, isExact, Ty, Tok.getLocation()); 1904 1905 } else if (!Literal.isIntegerLiteral()) { 1906 return ExprError(); 1907 } else { 1908 QualType Ty; 1909 1910 // long long is a C99 feature. 1911 if (!getLangOptions().C99 && !getLangOptions().CPlusPlus0x && 1912 Literal.isLongLong) 1913 Diag(Tok.getLocation(), diag::ext_longlong); 1914 1915 // Get the value in the widest-possible width. 1916 llvm::APInt ResultVal(Context.Target.getIntMaxTWidth(), 0); 1917 1918 if (Literal.GetIntegerValue(ResultVal)) { 1919 // If this value didn't fit into uintmax_t, warn and force to ull. 1920 Diag(Tok.getLocation(), diag::warn_integer_too_large); 1921 Ty = Context.UnsignedLongLongTy; 1922 assert(Context.getTypeSize(Ty) == ResultVal.getBitWidth() && 1923 "long long is not intmax_t?"); 1924 } else { 1925 // If this value fits into a ULL, try to figure out what else it fits into 1926 // according to the rules of C99 6.4.4.1p5. 1927 1928 // Octal, Hexadecimal, and integers with a U suffix are allowed to 1929 // be an unsigned int. 1930 bool AllowUnsigned = Literal.isUnsigned || Literal.getRadix() != 10; 1931 1932 // Check from smallest to largest, picking the smallest type we can. 1933 unsigned Width = 0; 1934 if (!Literal.isLong && !Literal.isLongLong) { 1935 // Are int/unsigned possibilities? 1936 unsigned IntSize = Context.Target.getIntWidth(); 1937 1938 // Does it fit in a unsigned int? 1939 if (ResultVal.isIntN(IntSize)) { 1940 // Does it fit in a signed int? 1941 if (!Literal.isUnsigned && ResultVal[IntSize-1] == 0) 1942 Ty = Context.IntTy; 1943 else if (AllowUnsigned) 1944 Ty = Context.UnsignedIntTy; 1945 Width = IntSize; 1946 } 1947 } 1948 1949 // Are long/unsigned long possibilities? 1950 if (Ty.isNull() && !Literal.isLongLong) { 1951 unsigned LongSize = Context.Target.getLongWidth(); 1952 1953 // Does it fit in a unsigned long? 1954 if (ResultVal.isIntN(LongSize)) { 1955 // Does it fit in a signed long? 1956 if (!Literal.isUnsigned && ResultVal[LongSize-1] == 0) 1957 Ty = Context.LongTy; 1958 else if (AllowUnsigned) 1959 Ty = Context.UnsignedLongTy; 1960 Width = LongSize; 1961 } 1962 } 1963 1964 // Finally, check long long if needed. 1965 if (Ty.isNull()) { 1966 unsigned LongLongSize = Context.Target.getLongLongWidth(); 1967 1968 // Does it fit in a unsigned long long? 1969 if (ResultVal.isIntN(LongLongSize)) { 1970 // Does it fit in a signed long long? 1971 if (!Literal.isUnsigned && ResultVal[LongLongSize-1] == 0) 1972 Ty = Context.LongLongTy; 1973 else if (AllowUnsigned) 1974 Ty = Context.UnsignedLongLongTy; 1975 Width = LongLongSize; 1976 } 1977 } 1978 1979 // If we still couldn't decide a type, we probably have something that 1980 // does not fit in a signed long long, but has no U suffix. 1981 if (Ty.isNull()) { 1982 Diag(Tok.getLocation(), diag::warn_integer_too_large_for_signed); 1983 Ty = Context.UnsignedLongLongTy; 1984 Width = Context.Target.getLongLongWidth(); 1985 } 1986 1987 if (ResultVal.getBitWidth() != Width) 1988 ResultVal.trunc(Width); 1989 } 1990 Res = new (Context) IntegerLiteral(ResultVal, Ty, Tok.getLocation()); 1991 } 1992 1993 // If this is an imaginary literal, create the ImaginaryLiteral wrapper. 1994 if (Literal.isImaginary) 1995 Res = new (Context) ImaginaryLiteral(Res, 1996 Context.getComplexType(Res->getType())); 1997 1998 return Owned(Res); 1999} 2000 2001Action::OwningExprResult Sema::ActOnParenExpr(SourceLocation L, 2002 SourceLocation R, ExprArg Val) { 2003 Expr *E = Val.takeAs<Expr>(); 2004 assert((E != 0) && "ActOnParenExpr() missing expr"); 2005 return Owned(new (Context) ParenExpr(L, R, E)); 2006} 2007 2008/// The UsualUnaryConversions() function is *not* called by this routine. 2009/// See C99 6.3.2.1p[2-4] for more details. 2010bool Sema::CheckSizeOfAlignOfOperand(QualType exprType, 2011 SourceLocation OpLoc, 2012 const SourceRange &ExprRange, 2013 bool isSizeof) { 2014 if (exprType->isDependentType()) 2015 return false; 2016 2017 // C++ [expr.sizeof]p2: "When applied to a reference or a reference type, 2018 // the result is the size of the referenced type." 2019 // C++ [expr.alignof]p3: "When alignof is applied to a reference type, the 2020 // result shall be the alignment of the referenced type." 2021 if (const ReferenceType *Ref = exprType->getAs<ReferenceType>()) 2022 exprType = Ref->getPointeeType(); 2023 2024 // C99 6.5.3.4p1: 2025 if (exprType->isFunctionType()) { 2026 // alignof(function) is allowed as an extension. 2027 if (isSizeof) 2028 Diag(OpLoc, diag::ext_sizeof_function_type) << ExprRange; 2029 return false; 2030 } 2031 2032 // Allow sizeof(void)/alignof(void) as an extension. 2033 if (exprType->isVoidType()) { 2034 Diag(OpLoc, diag::ext_sizeof_void_type) 2035 << (isSizeof ? "sizeof" : "__alignof") << ExprRange; 2036 return false; 2037 } 2038 2039 if (RequireCompleteType(OpLoc, exprType, 2040 PDiag(diag::err_sizeof_alignof_incomplete_type) 2041 << int(!isSizeof) << ExprRange)) 2042 return true; 2043 2044 // Reject sizeof(interface) and sizeof(interface<proto>) in 64-bit mode. 2045 if (LangOpts.ObjCNonFragileABI && exprType->isObjCObjectType()) { 2046 Diag(OpLoc, diag::err_sizeof_nonfragile_interface) 2047 << exprType << isSizeof << ExprRange; 2048 return true; 2049 } 2050 2051 if (Context.hasSameUnqualifiedType(exprType, Context.OverloadTy)) { 2052 Diag(OpLoc, diag::err_sizeof_alignof_overloaded_function_type) 2053 << !isSizeof << ExprRange; 2054 return true; 2055 } 2056 2057 return false; 2058} 2059 2060bool Sema::CheckAlignOfExpr(Expr *E, SourceLocation OpLoc, 2061 const SourceRange &ExprRange) { 2062 E = E->IgnoreParens(); 2063 2064 // alignof decl is always ok. 2065 if (isa<DeclRefExpr>(E)) 2066 return false; 2067 2068 // Cannot know anything else if the expression is dependent. 2069 if (E->isTypeDependent()) 2070 return false; 2071 2072 if (E->getBitField()) { 2073 Diag(OpLoc, diag::err_sizeof_alignof_bitfield) << 1 << ExprRange; 2074 return true; 2075 } 2076 2077 // Alignment of a field access is always okay, so long as it isn't a 2078 // bit-field. 2079 if (MemberExpr *ME = dyn_cast<MemberExpr>(E)) 2080 if (isa<FieldDecl>(ME->getMemberDecl())) 2081 return false; 2082 2083 return CheckSizeOfAlignOfOperand(E->getType(), OpLoc, ExprRange, false); 2084} 2085 2086/// \brief Build a sizeof or alignof expression given a type operand. 2087Action::OwningExprResult 2088Sema::CreateSizeOfAlignOfExpr(TypeSourceInfo *TInfo, 2089 SourceLocation OpLoc, 2090 bool isSizeOf, SourceRange R) { 2091 if (!TInfo) 2092 return ExprError(); 2093 2094 QualType T = TInfo->getType(); 2095 2096 if (!T->isDependentType() && 2097 CheckSizeOfAlignOfOperand(T, OpLoc, R, isSizeOf)) 2098 return ExprError(); 2099 2100 // C99 6.5.3.4p4: the type (an unsigned integer type) is size_t. 2101 return Owned(new (Context) SizeOfAlignOfExpr(isSizeOf, TInfo, 2102 Context.getSizeType(), OpLoc, 2103 R.getEnd())); 2104} 2105 2106/// \brief Build a sizeof or alignof expression given an expression 2107/// operand. 2108Action::OwningExprResult 2109Sema::CreateSizeOfAlignOfExpr(Expr *E, SourceLocation OpLoc, 2110 bool isSizeOf, SourceRange R) { 2111 // Verify that the operand is valid. 2112 bool isInvalid = false; 2113 if (E->isTypeDependent()) { 2114 // Delay type-checking for type-dependent expressions. 2115 } else if (!isSizeOf) { 2116 isInvalid = CheckAlignOfExpr(E, OpLoc, R); 2117 } else if (E->getBitField()) { // C99 6.5.3.4p1. 2118 Diag(OpLoc, diag::err_sizeof_alignof_bitfield) << 0; 2119 isInvalid = true; 2120 } else { 2121 isInvalid = CheckSizeOfAlignOfOperand(E->getType(), OpLoc, R, true); 2122 } 2123 2124 if (isInvalid) 2125 return ExprError(); 2126 2127 // C99 6.5.3.4p4: the type (an unsigned integer type) is size_t. 2128 return Owned(new (Context) SizeOfAlignOfExpr(isSizeOf, E, 2129 Context.getSizeType(), OpLoc, 2130 R.getEnd())); 2131} 2132 2133/// ActOnSizeOfAlignOfExpr - Handle @c sizeof(type) and @c sizeof @c expr and 2134/// the same for @c alignof and @c __alignof 2135/// Note that the ArgRange is invalid if isType is false. 2136Action::OwningExprResult 2137Sema::ActOnSizeOfAlignOfExpr(SourceLocation OpLoc, bool isSizeof, bool isType, 2138 void *TyOrEx, const SourceRange &ArgRange) { 2139 // If error parsing type, ignore. 2140 if (TyOrEx == 0) return ExprError(); 2141 2142 if (isType) { 2143 TypeSourceInfo *TInfo; 2144 (void) GetTypeFromParser(TyOrEx, &TInfo); 2145 return CreateSizeOfAlignOfExpr(TInfo, OpLoc, isSizeof, ArgRange); 2146 } 2147 2148 Expr *ArgEx = (Expr *)TyOrEx; 2149 Action::OwningExprResult Result 2150 = CreateSizeOfAlignOfExpr(ArgEx, OpLoc, isSizeof, ArgEx->getSourceRange()); 2151 2152 if (Result.isInvalid()) 2153 DeleteExpr(ArgEx); 2154 2155 return move(Result); 2156} 2157 2158QualType Sema::CheckRealImagOperand(Expr *&V, SourceLocation Loc, bool isReal) { 2159 if (V->isTypeDependent()) 2160 return Context.DependentTy; 2161 2162 // These operators return the element type of a complex type. 2163 if (const ComplexType *CT = V->getType()->getAs<ComplexType>()) 2164 return CT->getElementType(); 2165 2166 // Otherwise they pass through real integer and floating point types here. 2167 if (V->getType()->isArithmeticType()) 2168 return V->getType(); 2169 2170 // Reject anything else. 2171 Diag(Loc, diag::err_realimag_invalid_type) << V->getType() 2172 << (isReal ? "__real" : "__imag"); 2173 return QualType(); 2174} 2175 2176 2177 2178Action::OwningExprResult 2179Sema::ActOnPostfixUnaryOp(Scope *S, SourceLocation OpLoc, 2180 tok::TokenKind Kind, ExprArg Input) { 2181 UnaryOperator::Opcode Opc; 2182 switch (Kind) { 2183 default: assert(0 && "Unknown unary op!"); 2184 case tok::plusplus: Opc = UnaryOperator::PostInc; break; 2185 case tok::minusminus: Opc = UnaryOperator::PostDec; break; 2186 } 2187 2188 return BuildUnaryOp(S, OpLoc, Opc, move(Input)); 2189} 2190 2191Action::OwningExprResult 2192Sema::ActOnArraySubscriptExpr(Scope *S, ExprArg Base, SourceLocation LLoc, 2193 ExprArg Idx, SourceLocation RLoc) { 2194 // Since this might be a postfix expression, get rid of ParenListExprs. 2195 Base = MaybeConvertParenListExprToParenExpr(S, move(Base)); 2196 2197 Expr *LHSExp = static_cast<Expr*>(Base.get()), 2198 *RHSExp = static_cast<Expr*>(Idx.get()); 2199 2200 if (getLangOptions().CPlusPlus && 2201 (LHSExp->isTypeDependent() || RHSExp->isTypeDependent())) { 2202 Base.release(); 2203 Idx.release(); 2204 return Owned(new (Context) ArraySubscriptExpr(LHSExp, RHSExp, 2205 Context.DependentTy, RLoc)); 2206 } 2207 2208 if (getLangOptions().CPlusPlus && 2209 (LHSExp->getType()->isRecordType() || 2210 LHSExp->getType()->isEnumeralType() || 2211 RHSExp->getType()->isRecordType() || 2212 RHSExp->getType()->isEnumeralType())) { 2213 return CreateOverloadedArraySubscriptExpr(LLoc, RLoc, move(Base),move(Idx)); 2214 } 2215 2216 return CreateBuiltinArraySubscriptExpr(move(Base), LLoc, move(Idx), RLoc); 2217} 2218 2219 2220Action::OwningExprResult 2221Sema::CreateBuiltinArraySubscriptExpr(ExprArg Base, SourceLocation LLoc, 2222 ExprArg Idx, SourceLocation RLoc) { 2223 Expr *LHSExp = static_cast<Expr*>(Base.get()); 2224 Expr *RHSExp = static_cast<Expr*>(Idx.get()); 2225 2226 // Perform default conversions. 2227 if (!LHSExp->getType()->getAs<VectorType>()) 2228 DefaultFunctionArrayLvalueConversion(LHSExp); 2229 DefaultFunctionArrayLvalueConversion(RHSExp); 2230 2231 QualType LHSTy = LHSExp->getType(), RHSTy = RHSExp->getType(); 2232 2233 // C99 6.5.2.1p2: the expression e1[e2] is by definition precisely equivalent 2234 // to the expression *((e1)+(e2)). This means the array "Base" may actually be 2235 // in the subscript position. As a result, we need to derive the array base 2236 // and index from the expression types. 2237 Expr *BaseExpr, *IndexExpr; 2238 QualType ResultType; 2239 if (LHSTy->isDependentType() || RHSTy->isDependentType()) { 2240 BaseExpr = LHSExp; 2241 IndexExpr = RHSExp; 2242 ResultType = Context.DependentTy; 2243 } else if (const PointerType *PTy = LHSTy->getAs<PointerType>()) { 2244 BaseExpr = LHSExp; 2245 IndexExpr = RHSExp; 2246 ResultType = PTy->getPointeeType(); 2247 } else if (const PointerType *PTy = RHSTy->getAs<PointerType>()) { 2248 // Handle the uncommon case of "123[Ptr]". 2249 BaseExpr = RHSExp; 2250 IndexExpr = LHSExp; 2251 ResultType = PTy->getPointeeType(); 2252 } else if (const ObjCObjectPointerType *PTy = 2253 LHSTy->getAs<ObjCObjectPointerType>()) { 2254 BaseExpr = LHSExp; 2255 IndexExpr = RHSExp; 2256 ResultType = PTy->getPointeeType(); 2257 } else if (const ObjCObjectPointerType *PTy = 2258 RHSTy->getAs<ObjCObjectPointerType>()) { 2259 // Handle the uncommon case of "123[Ptr]". 2260 BaseExpr = RHSExp; 2261 IndexExpr = LHSExp; 2262 ResultType = PTy->getPointeeType(); 2263 } else if (const VectorType *VTy = LHSTy->getAs<VectorType>()) { 2264 BaseExpr = LHSExp; // vectors: V[123] 2265 IndexExpr = RHSExp; 2266 2267 // FIXME: need to deal with const... 2268 ResultType = VTy->getElementType(); 2269 } else if (LHSTy->isArrayType()) { 2270 // If we see an array that wasn't promoted by 2271 // DefaultFunctionArrayLvalueConversion, it must be an array that 2272 // wasn't promoted because of the C90 rule that doesn't 2273 // allow promoting non-lvalue arrays. Warn, then 2274 // force the promotion here. 2275 Diag(LHSExp->getLocStart(), diag::ext_subscript_non_lvalue) << 2276 LHSExp->getSourceRange(); 2277 ImpCastExprToType(LHSExp, Context.getArrayDecayedType(LHSTy), 2278 CastExpr::CK_ArrayToPointerDecay); 2279 LHSTy = LHSExp->getType(); 2280 2281 BaseExpr = LHSExp; 2282 IndexExpr = RHSExp; 2283 ResultType = LHSTy->getAs<PointerType>()->getPointeeType(); 2284 } else if (RHSTy->isArrayType()) { 2285 // Same as previous, except for 123[f().a] case 2286 Diag(RHSExp->getLocStart(), diag::ext_subscript_non_lvalue) << 2287 RHSExp->getSourceRange(); 2288 ImpCastExprToType(RHSExp, Context.getArrayDecayedType(RHSTy), 2289 CastExpr::CK_ArrayToPointerDecay); 2290 RHSTy = RHSExp->getType(); 2291 2292 BaseExpr = RHSExp; 2293 IndexExpr = LHSExp; 2294 ResultType = RHSTy->getAs<PointerType>()->getPointeeType(); 2295 } else { 2296 return ExprError(Diag(LLoc, diag::err_typecheck_subscript_value) 2297 << LHSExp->getSourceRange() << RHSExp->getSourceRange()); 2298 } 2299 // C99 6.5.2.1p1 2300 if (!(IndexExpr->getType()->isIntegerType() && 2301 IndexExpr->getType()->isScalarType()) && !IndexExpr->isTypeDependent()) 2302 return ExprError(Diag(LLoc, diag::err_typecheck_subscript_not_integer) 2303 << IndexExpr->getSourceRange()); 2304 2305 if ((IndexExpr->getType()->isSpecificBuiltinType(BuiltinType::Char_S) || 2306 IndexExpr->getType()->isSpecificBuiltinType(BuiltinType::Char_U)) 2307 && !IndexExpr->isTypeDependent()) 2308 Diag(LLoc, diag::warn_subscript_is_char) << IndexExpr->getSourceRange(); 2309 2310 // C99 6.5.2.1p1: "shall have type "pointer to *object* type". Similarly, 2311 // C++ [expr.sub]p1: The type "T" shall be a completely-defined object 2312 // type. Note that Functions are not objects, and that (in C99 parlance) 2313 // incomplete types are not object types. 2314 if (ResultType->isFunctionType()) { 2315 Diag(BaseExpr->getLocStart(), diag::err_subscript_function_type) 2316 << ResultType << BaseExpr->getSourceRange(); 2317 return ExprError(); 2318 } 2319 2320 if (!ResultType->isDependentType() && 2321 RequireCompleteType(LLoc, ResultType, 2322 PDiag(diag::err_subscript_incomplete_type) 2323 << BaseExpr->getSourceRange())) 2324 return ExprError(); 2325 2326 // Diagnose bad cases where we step over interface counts. 2327 if (ResultType->isObjCObjectType() && LangOpts.ObjCNonFragileABI) { 2328 Diag(LLoc, diag::err_subscript_nonfragile_interface) 2329 << ResultType << BaseExpr->getSourceRange(); 2330 return ExprError(); 2331 } 2332 2333 Base.release(); 2334 Idx.release(); 2335 return Owned(new (Context) ArraySubscriptExpr(LHSExp, RHSExp, 2336 ResultType, RLoc)); 2337} 2338 2339QualType Sema:: 2340CheckExtVectorComponent(QualType baseType, SourceLocation OpLoc, 2341 const IdentifierInfo *CompName, 2342 SourceLocation CompLoc) { 2343 // FIXME: Share logic with ExtVectorElementExpr::containsDuplicateElements, 2344 // see FIXME there. 2345 // 2346 // FIXME: This logic can be greatly simplified by splitting it along 2347 // halving/not halving and reworking the component checking. 2348 const ExtVectorType *vecType = baseType->getAs<ExtVectorType>(); 2349 2350 // The vector accessor can't exceed the number of elements. 2351 const char *compStr = CompName->getNameStart(); 2352 2353 // This flag determines whether or not the component is one of the four 2354 // special names that indicate a subset of exactly half the elements are 2355 // to be selected. 2356 bool HalvingSwizzle = false; 2357 2358 // This flag determines whether or not CompName has an 's' char prefix, 2359 // indicating that it is a string of hex values to be used as vector indices. 2360 bool HexSwizzle = *compStr == 's' || *compStr == 'S'; 2361 2362 // Check that we've found one of the special components, or that the component 2363 // names must come from the same set. 2364 if (!strcmp(compStr, "hi") || !strcmp(compStr, "lo") || 2365 !strcmp(compStr, "even") || !strcmp(compStr, "odd")) { 2366 HalvingSwizzle = true; 2367 } else if (vecType->getPointAccessorIdx(*compStr) != -1) { 2368 do 2369 compStr++; 2370 while (*compStr && vecType->getPointAccessorIdx(*compStr) != -1); 2371 } else if (HexSwizzle || vecType->getNumericAccessorIdx(*compStr) != -1) { 2372 do 2373 compStr++; 2374 while (*compStr && vecType->getNumericAccessorIdx(*compStr) != -1); 2375 } 2376 2377 if (!HalvingSwizzle && *compStr) { 2378 // We didn't get to the end of the string. This means the component names 2379 // didn't come from the same set *or* we encountered an illegal name. 2380 Diag(OpLoc, diag::err_ext_vector_component_name_illegal) 2381 << std::string(compStr,compStr+1) << SourceRange(CompLoc); 2382 return QualType(); 2383 } 2384 2385 // Ensure no component accessor exceeds the width of the vector type it 2386 // operates on. 2387 if (!HalvingSwizzle) { 2388 compStr = CompName->getNameStart(); 2389 2390 if (HexSwizzle) 2391 compStr++; 2392 2393 while (*compStr) { 2394 if (!vecType->isAccessorWithinNumElements(*compStr++)) { 2395 Diag(OpLoc, diag::err_ext_vector_component_exceeds_length) 2396 << baseType << SourceRange(CompLoc); 2397 return QualType(); 2398 } 2399 } 2400 } 2401 2402 // The component accessor looks fine - now we need to compute the actual type. 2403 // The vector type is implied by the component accessor. For example, 2404 // vec4.b is a float, vec4.xy is a vec2, vec4.rgb is a vec3, etc. 2405 // vec4.s0 is a float, vec4.s23 is a vec3, etc. 2406 // vec4.hi, vec4.lo, vec4.e, and vec4.o all return vec2. 2407 unsigned CompSize = HalvingSwizzle ? (vecType->getNumElements() + 1) / 2 2408 : CompName->getLength(); 2409 if (HexSwizzle) 2410 CompSize--; 2411 2412 if (CompSize == 1) 2413 return vecType->getElementType(); 2414 2415 QualType VT = Context.getExtVectorType(vecType->getElementType(), CompSize); 2416 // Now look up the TypeDefDecl from the vector type. Without this, 2417 // diagostics look bad. We want extended vector types to appear built-in. 2418 for (unsigned i = 0, E = ExtVectorDecls.size(); i != E; ++i) { 2419 if (ExtVectorDecls[i]->getUnderlyingType() == VT) 2420 return Context.getTypedefType(ExtVectorDecls[i]); 2421 } 2422 return VT; // should never get here (a typedef type should always be found). 2423} 2424 2425static Decl *FindGetterNameDeclFromProtocolList(const ObjCProtocolDecl*PDecl, 2426 IdentifierInfo *Member, 2427 const Selector &Sel, 2428 ASTContext &Context) { 2429 2430 if (ObjCPropertyDecl *PD = PDecl->FindPropertyDeclaration(Member)) 2431 return PD; 2432 if (ObjCMethodDecl *OMD = PDecl->getInstanceMethod(Sel)) 2433 return OMD; 2434 2435 for (ObjCProtocolDecl::protocol_iterator I = PDecl->protocol_begin(), 2436 E = PDecl->protocol_end(); I != E; ++I) { 2437 if (Decl *D = FindGetterNameDeclFromProtocolList(*I, Member, Sel, 2438 Context)) 2439 return D; 2440 } 2441 return 0; 2442} 2443 2444static Decl *FindGetterNameDecl(const ObjCObjectPointerType *QIdTy, 2445 IdentifierInfo *Member, 2446 const Selector &Sel, 2447 ASTContext &Context) { 2448 // Check protocols on qualified interfaces. 2449 Decl *GDecl = 0; 2450 for (ObjCObjectPointerType::qual_iterator I = QIdTy->qual_begin(), 2451 E = QIdTy->qual_end(); I != E; ++I) { 2452 if (ObjCPropertyDecl *PD = (*I)->FindPropertyDeclaration(Member)) { 2453 GDecl = PD; 2454 break; 2455 } 2456 // Also must look for a getter name which uses property syntax. 2457 if (ObjCMethodDecl *OMD = (*I)->getInstanceMethod(Sel)) { 2458 GDecl = OMD; 2459 break; 2460 } 2461 } 2462 if (!GDecl) { 2463 for (ObjCObjectPointerType::qual_iterator I = QIdTy->qual_begin(), 2464 E = QIdTy->qual_end(); I != E; ++I) { 2465 // Search in the protocol-qualifier list of current protocol. 2466 GDecl = FindGetterNameDeclFromProtocolList(*I, Member, Sel, Context); 2467 if (GDecl) 2468 return GDecl; 2469 } 2470 } 2471 return GDecl; 2472} 2473 2474Sema::OwningExprResult 2475Sema::ActOnDependentMemberExpr(ExprArg Base, QualType BaseType, 2476 bool IsArrow, SourceLocation OpLoc, 2477 const CXXScopeSpec &SS, 2478 NamedDecl *FirstQualifierInScope, 2479 DeclarationName Name, SourceLocation NameLoc, 2480 const TemplateArgumentListInfo *TemplateArgs) { 2481 Expr *BaseExpr = Base.takeAs<Expr>(); 2482 2483 // Even in dependent contexts, try to diagnose base expressions with 2484 // obviously wrong types, e.g.: 2485 // 2486 // T* t; 2487 // t.f; 2488 // 2489 // In Obj-C++, however, the above expression is valid, since it could be 2490 // accessing the 'f' property if T is an Obj-C interface. The extra check 2491 // allows this, while still reporting an error if T is a struct pointer. 2492 if (!IsArrow) { 2493 const PointerType *PT = BaseType->getAs<PointerType>(); 2494 if (PT && (!getLangOptions().ObjC1 || 2495 PT->getPointeeType()->isRecordType())) { 2496 assert(BaseExpr && "cannot happen with implicit member accesses"); 2497 Diag(NameLoc, diag::err_typecheck_member_reference_struct_union) 2498 << BaseType << BaseExpr->getSourceRange(); 2499 return ExprError(); 2500 } 2501 } 2502 2503 assert(BaseType->isDependentType() || Name.isDependentName() || 2504 isDependentScopeSpecifier(SS)); 2505 2506 // Get the type being accessed in BaseType. If this is an arrow, the BaseExpr 2507 // must have pointer type, and the accessed type is the pointee. 2508 return Owned(CXXDependentScopeMemberExpr::Create(Context, BaseExpr, BaseType, 2509 IsArrow, OpLoc, 2510 static_cast<NestedNameSpecifier*>(SS.getScopeRep()), 2511 SS.getRange(), 2512 FirstQualifierInScope, 2513 Name, NameLoc, 2514 TemplateArgs)); 2515} 2516 2517/// We know that the given qualified member reference points only to 2518/// declarations which do not belong to the static type of the base 2519/// expression. Diagnose the problem. 2520static void DiagnoseQualifiedMemberReference(Sema &SemaRef, 2521 Expr *BaseExpr, 2522 QualType BaseType, 2523 const CXXScopeSpec &SS, 2524 const LookupResult &R) { 2525 // If this is an implicit member access, use a different set of 2526 // diagnostics. 2527 if (!BaseExpr) 2528 return DiagnoseInstanceReference(SemaRef, SS, R); 2529 2530 SemaRef.Diag(R.getNameLoc(), diag::err_qualified_member_of_unrelated) 2531 << SS.getRange() << R.getRepresentativeDecl() << BaseType; 2532} 2533 2534// Check whether the declarations we found through a nested-name 2535// specifier in a member expression are actually members of the base 2536// type. The restriction here is: 2537// 2538// C++ [expr.ref]p2: 2539// ... In these cases, the id-expression shall name a 2540// member of the class or of one of its base classes. 2541// 2542// So it's perfectly legitimate for the nested-name specifier to name 2543// an unrelated class, and for us to find an overload set including 2544// decls from classes which are not superclasses, as long as the decl 2545// we actually pick through overload resolution is from a superclass. 2546bool Sema::CheckQualifiedMemberReference(Expr *BaseExpr, 2547 QualType BaseType, 2548 const CXXScopeSpec &SS, 2549 const LookupResult &R) { 2550 const RecordType *BaseRT = BaseType->getAs<RecordType>(); 2551 if (!BaseRT) { 2552 // We can't check this yet because the base type is still 2553 // dependent. 2554 assert(BaseType->isDependentType()); 2555 return false; 2556 } 2557 CXXRecordDecl *BaseRecord = cast<CXXRecordDecl>(BaseRT->getDecl()); 2558 2559 for (LookupResult::iterator I = R.begin(), E = R.end(); I != E; ++I) { 2560 // If this is an implicit member reference and we find a 2561 // non-instance member, it's not an error. 2562 if (!BaseExpr && !(*I)->isCXXInstanceMember()) 2563 return false; 2564 2565 // Note that we use the DC of the decl, not the underlying decl. 2566 CXXRecordDecl *RecordD = cast<CXXRecordDecl>((*I)->getDeclContext()); 2567 while (RecordD->isAnonymousStructOrUnion()) 2568 RecordD = cast<CXXRecordDecl>(RecordD->getParent()); 2569 2570 llvm::SmallPtrSet<CXXRecordDecl*,4> MemberRecord; 2571 MemberRecord.insert(RecordD->getCanonicalDecl()); 2572 2573 if (!IsProvablyNotDerivedFrom(*this, BaseRecord, MemberRecord)) 2574 return false; 2575 } 2576 2577 DiagnoseQualifiedMemberReference(*this, BaseExpr, BaseType, SS, R); 2578 return true; 2579} 2580 2581static bool 2582LookupMemberExprInRecord(Sema &SemaRef, LookupResult &R, 2583 SourceRange BaseRange, const RecordType *RTy, 2584 SourceLocation OpLoc, CXXScopeSpec &SS, 2585 bool HasTemplateArgs) { 2586 RecordDecl *RDecl = RTy->getDecl(); 2587 if (SemaRef.RequireCompleteType(OpLoc, QualType(RTy, 0), 2588 SemaRef.PDiag(diag::err_typecheck_incomplete_tag) 2589 << BaseRange)) 2590 return true; 2591 2592 if (HasTemplateArgs) { 2593 // LookupTemplateName doesn't expect these both to exist simultaneously. 2594 QualType ObjectType = SS.isSet() ? QualType() : QualType(RTy, 0); 2595 2596 bool MOUS; 2597 SemaRef.LookupTemplateName(R, 0, SS, ObjectType, false, MOUS); 2598 return false; 2599 } 2600 2601 DeclContext *DC = RDecl; 2602 if (SS.isSet()) { 2603 // If the member name was a qualified-id, look into the 2604 // nested-name-specifier. 2605 DC = SemaRef.computeDeclContext(SS, false); 2606 2607 if (SemaRef.RequireCompleteDeclContext(SS, DC)) { 2608 SemaRef.Diag(SS.getRange().getEnd(), diag::err_typecheck_incomplete_tag) 2609 << SS.getRange() << DC; 2610 return true; 2611 } 2612 2613 assert(DC && "Cannot handle non-computable dependent contexts in lookup"); 2614 2615 if (!isa<TypeDecl>(DC)) { 2616 SemaRef.Diag(R.getNameLoc(), diag::err_qualified_member_nonclass) 2617 << DC << SS.getRange(); 2618 return true; 2619 } 2620 } 2621 2622 // The record definition is complete, now look up the member. 2623 SemaRef.LookupQualifiedName(R, DC); 2624 2625 if (!R.empty()) 2626 return false; 2627 2628 // We didn't find anything with the given name, so try to correct 2629 // for typos. 2630 DeclarationName Name = R.getLookupName(); 2631 if (SemaRef.CorrectTypo(R, 0, &SS, DC, false, Sema::CTC_MemberLookup) && 2632 !R.empty() && 2633 (isa<ValueDecl>(*R.begin()) || isa<FunctionTemplateDecl>(*R.begin()))) { 2634 SemaRef.Diag(R.getNameLoc(), diag::err_no_member_suggest) 2635 << Name << DC << R.getLookupName() << SS.getRange() 2636 << FixItHint::CreateReplacement(R.getNameLoc(), 2637 R.getLookupName().getAsString()); 2638 if (NamedDecl *ND = R.getAsSingle<NamedDecl>()) 2639 SemaRef.Diag(ND->getLocation(), diag::note_previous_decl) 2640 << ND->getDeclName(); 2641 return false; 2642 } else { 2643 R.clear(); 2644 R.setLookupName(Name); 2645 } 2646 2647 return false; 2648} 2649 2650Sema::OwningExprResult 2651Sema::BuildMemberReferenceExpr(ExprArg BaseArg, QualType BaseType, 2652 SourceLocation OpLoc, bool IsArrow, 2653 CXXScopeSpec &SS, 2654 NamedDecl *FirstQualifierInScope, 2655 DeclarationName Name, SourceLocation NameLoc, 2656 const TemplateArgumentListInfo *TemplateArgs) { 2657 Expr *Base = BaseArg.takeAs<Expr>(); 2658 2659 if (BaseType->isDependentType() || 2660 (SS.isSet() && isDependentScopeSpecifier(SS))) 2661 return ActOnDependentMemberExpr(ExprArg(*this, Base), BaseType, 2662 IsArrow, OpLoc, 2663 SS, FirstQualifierInScope, 2664 Name, NameLoc, 2665 TemplateArgs); 2666 2667 LookupResult R(*this, Name, NameLoc, LookupMemberName); 2668 2669 // Implicit member accesses. 2670 if (!Base) { 2671 QualType RecordTy = BaseType; 2672 if (IsArrow) RecordTy = RecordTy->getAs<PointerType>()->getPointeeType(); 2673 if (LookupMemberExprInRecord(*this, R, SourceRange(), 2674 RecordTy->getAs<RecordType>(), 2675 OpLoc, SS, TemplateArgs != 0)) 2676 return ExprError(); 2677 2678 // Explicit member accesses. 2679 } else { 2680 OwningExprResult Result = 2681 LookupMemberExpr(R, Base, IsArrow, OpLoc, 2682 SS, /*ObjCImpDecl*/ DeclPtrTy(), TemplateArgs != 0); 2683 2684 if (Result.isInvalid()) { 2685 Owned(Base); 2686 return ExprError(); 2687 } 2688 2689 if (Result.get()) 2690 return move(Result); 2691 2692 // LookupMemberExpr can modify Base, and thus change BaseType 2693 BaseType = Base->getType(); 2694 } 2695 2696 return BuildMemberReferenceExpr(ExprArg(*this, Base), BaseType, 2697 OpLoc, IsArrow, SS, FirstQualifierInScope, 2698 R, TemplateArgs); 2699} 2700 2701Sema::OwningExprResult 2702Sema::BuildMemberReferenceExpr(ExprArg Base, QualType BaseExprType, 2703 SourceLocation OpLoc, bool IsArrow, 2704 const CXXScopeSpec &SS, 2705 NamedDecl *FirstQualifierInScope, 2706 LookupResult &R, 2707 const TemplateArgumentListInfo *TemplateArgs, 2708 bool SuppressQualifierCheck) { 2709 Expr *BaseExpr = Base.takeAs<Expr>(); 2710 QualType BaseType = BaseExprType; 2711 if (IsArrow) { 2712 assert(BaseType->isPointerType()); 2713 BaseType = BaseType->getAs<PointerType>()->getPointeeType(); 2714 } 2715 R.setBaseObjectType(BaseType); 2716 2717 NestedNameSpecifier *Qualifier = 2718 static_cast<NestedNameSpecifier*>(SS.getScopeRep()); 2719 DeclarationName MemberName = R.getLookupName(); 2720 SourceLocation MemberLoc = R.getNameLoc(); 2721 2722 if (R.isAmbiguous()) 2723 return ExprError(); 2724 2725 if (R.empty()) { 2726 // Rederive where we looked up. 2727 DeclContext *DC = (SS.isSet() 2728 ? computeDeclContext(SS, false) 2729 : BaseType->getAs<RecordType>()->getDecl()); 2730 2731 Diag(R.getNameLoc(), diag::err_no_member) 2732 << MemberName << DC 2733 << (BaseExpr ? BaseExpr->getSourceRange() : SourceRange()); 2734 return ExprError(); 2735 } 2736 2737 // Diagnose lookups that find only declarations from a non-base 2738 // type. This is possible for either qualified lookups (which may 2739 // have been qualified with an unrelated type) or implicit member 2740 // expressions (which were found with unqualified lookup and thus 2741 // may have come from an enclosing scope). Note that it's okay for 2742 // lookup to find declarations from a non-base type as long as those 2743 // aren't the ones picked by overload resolution. 2744 if ((SS.isSet() || !BaseExpr || 2745 (isa<CXXThisExpr>(BaseExpr) && 2746 cast<CXXThisExpr>(BaseExpr)->isImplicit())) && 2747 !SuppressQualifierCheck && 2748 CheckQualifiedMemberReference(BaseExpr, BaseType, SS, R)) 2749 return ExprError(); 2750 2751 // Construct an unresolved result if we in fact got an unresolved 2752 // result. 2753 if (R.isOverloadedResult() || R.isUnresolvableResult()) { 2754 bool Dependent = 2755 BaseExprType->isDependentType() || 2756 R.isUnresolvableResult() || 2757 OverloadExpr::ComputeDependence(R.begin(), R.end(), TemplateArgs); 2758 2759 // Suppress any lookup-related diagnostics; we'll do these when we 2760 // pick a member. 2761 R.suppressDiagnostics(); 2762 2763 UnresolvedMemberExpr *MemExpr 2764 = UnresolvedMemberExpr::Create(Context, Dependent, 2765 R.isUnresolvableResult(), 2766 BaseExpr, BaseExprType, 2767 IsArrow, OpLoc, 2768 Qualifier, SS.getRange(), 2769 MemberName, MemberLoc, 2770 TemplateArgs, R.begin(), R.end()); 2771 2772 return Owned(MemExpr); 2773 } 2774 2775 assert(R.isSingleResult()); 2776 DeclAccessPair FoundDecl = R.begin().getPair(); 2777 NamedDecl *MemberDecl = R.getFoundDecl(); 2778 2779 // FIXME: diagnose the presence of template arguments now. 2780 2781 // If the decl being referenced had an error, return an error for this 2782 // sub-expr without emitting another error, in order to avoid cascading 2783 // error cases. 2784 if (MemberDecl->isInvalidDecl()) 2785 return ExprError(); 2786 2787 // Handle the implicit-member-access case. 2788 if (!BaseExpr) { 2789 // If this is not an instance member, convert to a non-member access. 2790 if (!MemberDecl->isCXXInstanceMember()) 2791 return BuildDeclarationNameExpr(SS, R.getNameLoc(), MemberDecl); 2792 2793 SourceLocation Loc = R.getNameLoc(); 2794 if (SS.getRange().isValid()) 2795 Loc = SS.getRange().getBegin(); 2796 BaseExpr = new (Context) CXXThisExpr(Loc, BaseExprType,/*isImplicit=*/true); 2797 } 2798 2799 bool ShouldCheckUse = true; 2800 if (CXXMethodDecl *MD = dyn_cast<CXXMethodDecl>(MemberDecl)) { 2801 // Don't diagnose the use of a virtual member function unless it's 2802 // explicitly qualified. 2803 if (MD->isVirtual() && !SS.isSet()) 2804 ShouldCheckUse = false; 2805 } 2806 2807 // Check the use of this member. 2808 if (ShouldCheckUse && DiagnoseUseOfDecl(MemberDecl, MemberLoc)) { 2809 Owned(BaseExpr); 2810 return ExprError(); 2811 } 2812 2813 if (FieldDecl *FD = dyn_cast<FieldDecl>(MemberDecl)) { 2814 // We may have found a field within an anonymous union or struct 2815 // (C++ [class.union]). 2816 if (cast<RecordDecl>(FD->getDeclContext())->isAnonymousStructOrUnion() && 2817 !BaseType->getAs<RecordType>()->getDecl()->isAnonymousStructOrUnion()) 2818 return BuildAnonymousStructUnionMemberReference(MemberLoc, FD, 2819 BaseExpr, OpLoc); 2820 2821 // Figure out the type of the member; see C99 6.5.2.3p3, C++ [expr.ref] 2822 QualType MemberType = FD->getType(); 2823 if (const ReferenceType *Ref = MemberType->getAs<ReferenceType>()) 2824 MemberType = Ref->getPointeeType(); 2825 else { 2826 Qualifiers BaseQuals = BaseType.getQualifiers(); 2827 BaseQuals.removeObjCGCAttr(); 2828 if (FD->isMutable()) BaseQuals.removeConst(); 2829 2830 Qualifiers MemberQuals 2831 = Context.getCanonicalType(MemberType).getQualifiers(); 2832 2833 Qualifiers Combined = BaseQuals + MemberQuals; 2834 if (Combined != MemberQuals) 2835 MemberType = Context.getQualifiedType(MemberType, Combined); 2836 } 2837 2838 MarkDeclarationReferenced(MemberLoc, FD); 2839 if (PerformObjectMemberConversion(BaseExpr, Qualifier, FoundDecl, FD)) 2840 return ExprError(); 2841 return Owned(BuildMemberExpr(Context, BaseExpr, IsArrow, SS, 2842 FD, FoundDecl, MemberLoc, MemberType)); 2843 } 2844 2845 if (VarDecl *Var = dyn_cast<VarDecl>(MemberDecl)) { 2846 MarkDeclarationReferenced(MemberLoc, Var); 2847 return Owned(BuildMemberExpr(Context, BaseExpr, IsArrow, SS, 2848 Var, FoundDecl, MemberLoc, 2849 Var->getType().getNonReferenceType())); 2850 } 2851 2852 if (FunctionDecl *MemberFn = dyn_cast<FunctionDecl>(MemberDecl)) { 2853 MarkDeclarationReferenced(MemberLoc, MemberDecl); 2854 return Owned(BuildMemberExpr(Context, BaseExpr, IsArrow, SS, 2855 MemberFn, FoundDecl, MemberLoc, 2856 MemberFn->getType())); 2857 } 2858 2859 if (EnumConstantDecl *Enum = dyn_cast<EnumConstantDecl>(MemberDecl)) { 2860 MarkDeclarationReferenced(MemberLoc, MemberDecl); 2861 return Owned(BuildMemberExpr(Context, BaseExpr, IsArrow, SS, 2862 Enum, FoundDecl, MemberLoc, Enum->getType())); 2863 } 2864 2865 Owned(BaseExpr); 2866 2867 // We found something that we didn't expect. Complain. 2868 if (isa<TypeDecl>(MemberDecl)) 2869 Diag(MemberLoc,diag::err_typecheck_member_reference_type) 2870 << MemberName << BaseType << int(IsArrow); 2871 else 2872 Diag(MemberLoc, diag::err_typecheck_member_reference_unknown) 2873 << MemberName << BaseType << int(IsArrow); 2874 2875 Diag(MemberDecl->getLocation(), diag::note_member_declared_here) 2876 << MemberName; 2877 R.suppressDiagnostics(); 2878 return ExprError(); 2879} 2880 2881/// Look up the given member of the given non-type-dependent 2882/// expression. This can return in one of two ways: 2883/// * If it returns a sentinel null-but-valid result, the caller will 2884/// assume that lookup was performed and the results written into 2885/// the provided structure. It will take over from there. 2886/// * Otherwise, the returned expression will be produced in place of 2887/// an ordinary member expression. 2888/// 2889/// The ObjCImpDecl bit is a gross hack that will need to be properly 2890/// fixed for ObjC++. 2891Sema::OwningExprResult 2892Sema::LookupMemberExpr(LookupResult &R, Expr *&BaseExpr, 2893 bool &IsArrow, SourceLocation OpLoc, 2894 CXXScopeSpec &SS, 2895 DeclPtrTy ObjCImpDecl, bool HasTemplateArgs) { 2896 assert(BaseExpr && "no base expression"); 2897 2898 // Perform default conversions. 2899 DefaultFunctionArrayConversion(BaseExpr); 2900 2901 QualType BaseType = BaseExpr->getType(); 2902 assert(!BaseType->isDependentType()); 2903 2904 DeclarationName MemberName = R.getLookupName(); 2905 SourceLocation MemberLoc = R.getNameLoc(); 2906 2907 // If the user is trying to apply -> or . to a function pointer 2908 // type, it's probably because they forgot parentheses to call that 2909 // function. Suggest the addition of those parentheses, build the 2910 // call, and continue on. 2911 if (const PointerType *Ptr = BaseType->getAs<PointerType>()) { 2912 if (const FunctionProtoType *Fun 2913 = Ptr->getPointeeType()->getAs<FunctionProtoType>()) { 2914 QualType ResultTy = Fun->getResultType(); 2915 if (Fun->getNumArgs() == 0 && 2916 ((!IsArrow && ResultTy->isRecordType()) || 2917 (IsArrow && ResultTy->isPointerType() && 2918 ResultTy->getAs<PointerType>()->getPointeeType() 2919 ->isRecordType()))) { 2920 SourceLocation Loc = PP.getLocForEndOfToken(BaseExpr->getLocEnd()); 2921 Diag(Loc, diag::err_member_reference_needs_call) 2922 << QualType(Fun, 0) 2923 << FixItHint::CreateInsertion(Loc, "()"); 2924 2925 OwningExprResult NewBase 2926 = ActOnCallExpr(0, ExprArg(*this, BaseExpr), Loc, 2927 MultiExprArg(*this, 0, 0), 0, Loc); 2928 BaseExpr = 0; 2929 if (NewBase.isInvalid()) 2930 return ExprError(); 2931 2932 BaseExpr = NewBase.takeAs<Expr>(); 2933 DefaultFunctionArrayConversion(BaseExpr); 2934 BaseType = BaseExpr->getType(); 2935 } 2936 } 2937 } 2938 2939 // If this is an Objective-C pseudo-builtin and a definition is provided then 2940 // use that. 2941 if (BaseType->isObjCIdType()) { 2942 if (IsArrow) { 2943 // Handle the following exceptional case PObj->isa. 2944 if (const ObjCObjectPointerType *OPT = 2945 BaseType->getAs<ObjCObjectPointerType>()) { 2946 if (OPT->getObjectType()->isObjCId() && 2947 MemberName.getAsIdentifierInfo()->isStr("isa")) 2948 return Owned(new (Context) ObjCIsaExpr(BaseExpr, true, MemberLoc, 2949 Context.getObjCClassType())); 2950 } 2951 } 2952 // We have an 'id' type. Rather than fall through, we check if this 2953 // is a reference to 'isa'. 2954 if (BaseType != Context.ObjCIdRedefinitionType) { 2955 BaseType = Context.ObjCIdRedefinitionType; 2956 ImpCastExprToType(BaseExpr, BaseType, CastExpr::CK_BitCast); 2957 } 2958 } 2959 2960 // If this is an Objective-C pseudo-builtin and a definition is provided then 2961 // use that. 2962 if (Context.isObjCSelType(BaseType)) { 2963 // We have an 'SEL' type. Rather than fall through, we check if this 2964 // is a reference to 'sel_id'. 2965 if (BaseType != Context.ObjCSelRedefinitionType) { 2966 BaseType = Context.ObjCSelRedefinitionType; 2967 ImpCastExprToType(BaseExpr, BaseType, CastExpr::CK_BitCast); 2968 } 2969 } 2970 2971 assert(!BaseType.isNull() && "no type for member expression"); 2972 2973 // Handle properties on ObjC 'Class' types. 2974 if (!IsArrow && BaseType->isObjCClassType()) { 2975 // Also must look for a getter name which uses property syntax. 2976 IdentifierInfo *Member = MemberName.getAsIdentifierInfo(); 2977 Selector Sel = PP.getSelectorTable().getNullarySelector(Member); 2978 if (ObjCMethodDecl *MD = getCurMethodDecl()) { 2979 ObjCInterfaceDecl *IFace = MD->getClassInterface(); 2980 ObjCMethodDecl *Getter; 2981 // FIXME: need to also look locally in the implementation. 2982 if ((Getter = IFace->lookupClassMethod(Sel))) { 2983 // Check the use of this method. 2984 if (DiagnoseUseOfDecl(Getter, MemberLoc)) 2985 return ExprError(); 2986 } 2987 // If we found a getter then this may be a valid dot-reference, we 2988 // will look for the matching setter, in case it is needed. 2989 Selector SetterSel = 2990 SelectorTable::constructSetterName(PP.getIdentifierTable(), 2991 PP.getSelectorTable(), Member); 2992 ObjCMethodDecl *Setter = IFace->lookupClassMethod(SetterSel); 2993 if (!Setter) { 2994 // If this reference is in an @implementation, also check for 'private' 2995 // methods. 2996 Setter = IFace->lookupPrivateInstanceMethod(SetterSel); 2997 } 2998 // Look through local category implementations associated with the class. 2999 if (!Setter) 3000 Setter = IFace->getCategoryClassMethod(SetterSel); 3001 3002 if (Setter && DiagnoseUseOfDecl(Setter, MemberLoc)) 3003 return ExprError(); 3004 3005 if (Getter || Setter) { 3006 QualType PType; 3007 3008 if (Getter) 3009 PType = Getter->getResultType(); 3010 else 3011 // Get the expression type from Setter's incoming parameter. 3012 PType = (*(Setter->param_end() -1))->getType(); 3013 // FIXME: we must check that the setter has property type. 3014 return Owned(new (Context) ObjCImplicitSetterGetterRefExpr(Getter, 3015 PType, 3016 Setter, MemberLoc, BaseExpr)); 3017 } 3018 return ExprError(Diag(MemberLoc, diag::err_property_not_found) 3019 << MemberName << BaseType); 3020 } 3021 } 3022 3023 if (BaseType->isObjCClassType() && 3024 BaseType != Context.ObjCClassRedefinitionType) { 3025 BaseType = Context.ObjCClassRedefinitionType; 3026 ImpCastExprToType(BaseExpr, BaseType, CastExpr::CK_BitCast); 3027 } 3028 3029 if (IsArrow) { 3030 if (const PointerType *PT = BaseType->getAs<PointerType>()) 3031 BaseType = PT->getPointeeType(); 3032 else if (BaseType->isObjCObjectPointerType()) 3033 ; 3034 else if (BaseType->isRecordType()) { 3035 // Recover from arrow accesses to records, e.g.: 3036 // struct MyRecord foo; 3037 // foo->bar 3038 // This is actually well-formed in C++ if MyRecord has an 3039 // overloaded operator->, but that should have been dealt with 3040 // by now. 3041 Diag(OpLoc, diag::err_typecheck_member_reference_suggestion) 3042 << BaseType << int(IsArrow) << BaseExpr->getSourceRange() 3043 << FixItHint::CreateReplacement(OpLoc, "."); 3044 IsArrow = false; 3045 } else { 3046 Diag(MemberLoc, diag::err_typecheck_member_reference_arrow) 3047 << BaseType << BaseExpr->getSourceRange(); 3048 return ExprError(); 3049 } 3050 } else { 3051 // Recover from dot accesses to pointers, e.g.: 3052 // type *foo; 3053 // foo.bar 3054 // This is actually well-formed in two cases: 3055 // - 'type' is an Objective C type 3056 // - 'bar' is a pseudo-destructor name which happens to refer to 3057 // the appropriate pointer type 3058 if (MemberName.getNameKind() != DeclarationName::CXXDestructorName) { 3059 const PointerType *PT = BaseType->getAs<PointerType>(); 3060 if (PT && PT->getPointeeType()->isRecordType()) { 3061 Diag(OpLoc, diag::err_typecheck_member_reference_suggestion) 3062 << BaseType << int(IsArrow) << BaseExpr->getSourceRange() 3063 << FixItHint::CreateReplacement(OpLoc, "->"); 3064 BaseType = PT->getPointeeType(); 3065 IsArrow = true; 3066 } 3067 } 3068 } 3069 3070 // Handle field access to simple records. 3071 if (const RecordType *RTy = BaseType->getAs<RecordType>()) { 3072 if (LookupMemberExprInRecord(*this, R, BaseExpr->getSourceRange(), 3073 RTy, OpLoc, SS, HasTemplateArgs)) 3074 return ExprError(); 3075 return Owned((Expr*) 0); 3076 } 3077 3078 // Handle access to Objective-C instance variables, such as "Obj->ivar" and 3079 // (*Obj).ivar. 3080 if ((IsArrow && BaseType->isObjCObjectPointerType()) || 3081 (!IsArrow && BaseType->isObjCObjectType())) { 3082 const ObjCObjectPointerType *OPT = BaseType->getAs<ObjCObjectPointerType>(); 3083 ObjCInterfaceDecl *IDecl = 3084 OPT ? OPT->getInterfaceDecl() 3085 : BaseType->getAs<ObjCObjectType>()->getInterface(); 3086 if (IDecl) { 3087 IdentifierInfo *Member = MemberName.getAsIdentifierInfo(); 3088 3089 ObjCInterfaceDecl *ClassDeclared; 3090 ObjCIvarDecl *IV = IDecl->lookupInstanceVariable(Member, ClassDeclared); 3091 3092 if (!IV) { 3093 // Attempt to correct for typos in ivar names. 3094 LookupResult Res(*this, R.getLookupName(), R.getNameLoc(), 3095 LookupMemberName); 3096 if (CorrectTypo(Res, 0, 0, IDecl, false, CTC_MemberLookup) && 3097 (IV = Res.getAsSingle<ObjCIvarDecl>())) { 3098 Diag(R.getNameLoc(), 3099 diag::err_typecheck_member_reference_ivar_suggest) 3100 << IDecl->getDeclName() << MemberName << IV->getDeclName() 3101 << FixItHint::CreateReplacement(R.getNameLoc(), 3102 IV->getNameAsString()); 3103 Diag(IV->getLocation(), diag::note_previous_decl) 3104 << IV->getDeclName(); 3105 } else { 3106 Res.clear(); 3107 Res.setLookupName(Member); 3108 } 3109 } 3110 3111 if (IV) { 3112 // If the decl being referenced had an error, return an error for this 3113 // sub-expr without emitting another error, in order to avoid cascading 3114 // error cases. 3115 if (IV->isInvalidDecl()) 3116 return ExprError(); 3117 3118 // Check whether we can reference this field. 3119 if (DiagnoseUseOfDecl(IV, MemberLoc)) 3120 return ExprError(); 3121 if (IV->getAccessControl() != ObjCIvarDecl::Public && 3122 IV->getAccessControl() != ObjCIvarDecl::Package) { 3123 ObjCInterfaceDecl *ClassOfMethodDecl = 0; 3124 if (ObjCMethodDecl *MD = getCurMethodDecl()) 3125 ClassOfMethodDecl = MD->getClassInterface(); 3126 else if (ObjCImpDecl && getCurFunctionDecl()) { 3127 // Case of a c-function declared inside an objc implementation. 3128 // FIXME: For a c-style function nested inside an objc implementation 3129 // class, there is no implementation context available, so we pass 3130 // down the context as argument to this routine. Ideally, this context 3131 // need be passed down in the AST node and somehow calculated from the 3132 // AST for a function decl. 3133 Decl *ImplDecl = ObjCImpDecl.getAs<Decl>(); 3134 if (ObjCImplementationDecl *IMPD = 3135 dyn_cast<ObjCImplementationDecl>(ImplDecl)) 3136 ClassOfMethodDecl = IMPD->getClassInterface(); 3137 else if (ObjCCategoryImplDecl* CatImplClass = 3138 dyn_cast<ObjCCategoryImplDecl>(ImplDecl)) 3139 ClassOfMethodDecl = CatImplClass->getClassInterface(); 3140 } 3141 3142 if (IV->getAccessControl() == ObjCIvarDecl::Private) { 3143 if (ClassDeclared != IDecl || 3144 ClassOfMethodDecl != ClassDeclared) 3145 Diag(MemberLoc, diag::error_private_ivar_access) 3146 << IV->getDeclName(); 3147 } else if (!IDecl->isSuperClassOf(ClassOfMethodDecl)) 3148 // @protected 3149 Diag(MemberLoc, diag::error_protected_ivar_access) 3150 << IV->getDeclName(); 3151 } 3152 3153 return Owned(new (Context) ObjCIvarRefExpr(IV, IV->getType(), 3154 MemberLoc, BaseExpr, 3155 IsArrow)); 3156 } 3157 return ExprError(Diag(MemberLoc, diag::err_typecheck_member_reference_ivar) 3158 << IDecl->getDeclName() << MemberName 3159 << BaseExpr->getSourceRange()); 3160 } 3161 } 3162 // Handle properties on 'id' and qualified "id". 3163 if (!IsArrow && (BaseType->isObjCIdType() || 3164 BaseType->isObjCQualifiedIdType())) { 3165 const ObjCObjectPointerType *QIdTy = BaseType->getAs<ObjCObjectPointerType>(); 3166 IdentifierInfo *Member = MemberName.getAsIdentifierInfo(); 3167 3168 // Check protocols on qualified interfaces. 3169 Selector Sel = PP.getSelectorTable().getNullarySelector(Member); 3170 if (Decl *PMDecl = FindGetterNameDecl(QIdTy, Member, Sel, Context)) { 3171 if (ObjCPropertyDecl *PD = dyn_cast<ObjCPropertyDecl>(PMDecl)) { 3172 // Check the use of this declaration 3173 if (DiagnoseUseOfDecl(PD, MemberLoc)) 3174 return ExprError(); 3175 3176 return Owned(new (Context) ObjCPropertyRefExpr(PD, PD->getType(), 3177 MemberLoc, BaseExpr)); 3178 } 3179 if (ObjCMethodDecl *OMD = dyn_cast<ObjCMethodDecl>(PMDecl)) { 3180 // Check the use of this method. 3181 if (DiagnoseUseOfDecl(OMD, MemberLoc)) 3182 return ExprError(); 3183 3184 return Owned(ObjCMessageExpr::Create(Context, 3185 OMD->getResultType().getNonReferenceType(), 3186 OpLoc, BaseExpr, Sel, 3187 OMD, NULL, 0, MemberLoc)); 3188 } 3189 } 3190 3191 return ExprError(Diag(MemberLoc, diag::err_property_not_found) 3192 << MemberName << BaseType); 3193 } 3194 3195 // Handle Objective-C property access, which is "Obj.property" where Obj is a 3196 // pointer to a (potentially qualified) interface type. 3197 if (!IsArrow) 3198 if (const ObjCObjectPointerType *OPT = 3199 BaseType->getAsObjCInterfacePointerType()) 3200 return HandleExprPropertyRefExpr(OPT, BaseExpr, MemberName, MemberLoc); 3201 3202 // Handle the following exceptional case (*Obj).isa. 3203 if (!IsArrow && 3204 BaseType->isObjCObjectType() && 3205 BaseType->getAs<ObjCObjectType>()->isObjCId() && 3206 MemberName.getAsIdentifierInfo()->isStr("isa")) 3207 return Owned(new (Context) ObjCIsaExpr(BaseExpr, false, MemberLoc, 3208 Context.getObjCClassType())); 3209 3210 // Handle 'field access' to vectors, such as 'V.xx'. 3211 if (BaseType->isExtVectorType()) { 3212 IdentifierInfo *Member = MemberName.getAsIdentifierInfo(); 3213 QualType ret = CheckExtVectorComponent(BaseType, OpLoc, Member, MemberLoc); 3214 if (ret.isNull()) 3215 return ExprError(); 3216 return Owned(new (Context) ExtVectorElementExpr(ret, BaseExpr, *Member, 3217 MemberLoc)); 3218 } 3219 3220 Diag(MemberLoc, diag::err_typecheck_member_reference_struct_union) 3221 << BaseType << BaseExpr->getSourceRange(); 3222 3223 return ExprError(); 3224} 3225 3226/// The main callback when the parser finds something like 3227/// expression . [nested-name-specifier] identifier 3228/// expression -> [nested-name-specifier] identifier 3229/// where 'identifier' encompasses a fairly broad spectrum of 3230/// possibilities, including destructor and operator references. 3231/// 3232/// \param OpKind either tok::arrow or tok::period 3233/// \param HasTrailingLParen whether the next token is '(', which 3234/// is used to diagnose mis-uses of special members that can 3235/// only be called 3236/// \param ObjCImpDecl the current ObjC @implementation decl; 3237/// this is an ugly hack around the fact that ObjC @implementations 3238/// aren't properly put in the context chain 3239Sema::OwningExprResult Sema::ActOnMemberAccessExpr(Scope *S, ExprArg BaseArg, 3240 SourceLocation OpLoc, 3241 tok::TokenKind OpKind, 3242 CXXScopeSpec &SS, 3243 UnqualifiedId &Id, 3244 DeclPtrTy ObjCImpDecl, 3245 bool HasTrailingLParen) { 3246 if (SS.isSet() && SS.isInvalid()) 3247 return ExprError(); 3248 3249 TemplateArgumentListInfo TemplateArgsBuffer; 3250 3251 // Decompose the name into its component parts. 3252 DeclarationName Name; 3253 SourceLocation NameLoc; 3254 const TemplateArgumentListInfo *TemplateArgs; 3255 DecomposeUnqualifiedId(*this, Id, TemplateArgsBuffer, 3256 Name, NameLoc, TemplateArgs); 3257 3258 bool IsArrow = (OpKind == tok::arrow); 3259 3260 NamedDecl *FirstQualifierInScope 3261 = (!SS.isSet() ? 0 : FindFirstQualifierInScope(S, 3262 static_cast<NestedNameSpecifier*>(SS.getScopeRep()))); 3263 3264 // This is a postfix expression, so get rid of ParenListExprs. 3265 BaseArg = MaybeConvertParenListExprToParenExpr(S, move(BaseArg)); 3266 3267 Expr *Base = BaseArg.takeAs<Expr>(); 3268 OwningExprResult Result(*this); 3269 if (Base->getType()->isDependentType() || Name.isDependentName() || 3270 isDependentScopeSpecifier(SS)) { 3271 Result = ActOnDependentMemberExpr(ExprArg(*this, Base), Base->getType(), 3272 IsArrow, OpLoc, 3273 SS, FirstQualifierInScope, 3274 Name, NameLoc, 3275 TemplateArgs); 3276 } else { 3277 LookupResult R(*this, Name, NameLoc, LookupMemberName); 3278 Result = LookupMemberExpr(R, Base, IsArrow, OpLoc, 3279 SS, ObjCImpDecl, TemplateArgs != 0); 3280 3281 if (Result.isInvalid()) { 3282 Owned(Base); 3283 return ExprError(); 3284 } 3285 3286 if (Result.get()) { 3287 // The only way a reference to a destructor can be used is to 3288 // immediately call it, which falls into this case. If the 3289 // next token is not a '(', produce a diagnostic and build the 3290 // call now. 3291 if (!HasTrailingLParen && 3292 Id.getKind() == UnqualifiedId::IK_DestructorName) 3293 return DiagnoseDtorReference(NameLoc, move(Result)); 3294 3295 return move(Result); 3296 } 3297 3298 Result = BuildMemberReferenceExpr(ExprArg(*this, Base), Base->getType(), 3299 OpLoc, IsArrow, SS, FirstQualifierInScope, 3300 R, TemplateArgs); 3301 } 3302 3303 return move(Result); 3304} 3305 3306Sema::OwningExprResult Sema::BuildCXXDefaultArgExpr(SourceLocation CallLoc, 3307 FunctionDecl *FD, 3308 ParmVarDecl *Param) { 3309 if (Param->hasUnparsedDefaultArg()) { 3310 Diag (CallLoc, 3311 diag::err_use_of_default_argument_to_function_declared_later) << 3312 FD << cast<CXXRecordDecl>(FD->getDeclContext())->getDeclName(); 3313 Diag(UnparsedDefaultArgLocs[Param], 3314 diag::note_default_argument_declared_here); 3315 } else { 3316 if (Param->hasUninstantiatedDefaultArg()) { 3317 Expr *UninstExpr = Param->getUninstantiatedDefaultArg(); 3318 3319 // Instantiate the expression. 3320 MultiLevelTemplateArgumentList ArgList 3321 = getTemplateInstantiationArgs(FD, 0, /*RelativeToPrimary=*/true); 3322 3323 std::pair<const TemplateArgument *, unsigned> Innermost 3324 = ArgList.getInnermost(); 3325 InstantiatingTemplate Inst(*this, CallLoc, Param, Innermost.first, 3326 Innermost.second); 3327 3328 OwningExprResult Result = SubstExpr(UninstExpr, ArgList); 3329 if (Result.isInvalid()) 3330 return ExprError(); 3331 3332 // Check the expression as an initializer for the parameter. 3333 InitializedEntity Entity 3334 = InitializedEntity::InitializeParameter(Param); 3335 InitializationKind Kind 3336 = InitializationKind::CreateCopy(Param->getLocation(), 3337 /*FIXME:EqualLoc*/UninstExpr->getSourceRange().getBegin()); 3338 Expr *ResultE = Result.takeAs<Expr>(); 3339 3340 InitializationSequence InitSeq(*this, Entity, Kind, &ResultE, 1); 3341 Result = InitSeq.Perform(*this, Entity, Kind, 3342 MultiExprArg(*this, (void**)&ResultE, 1)); 3343 if (Result.isInvalid()) 3344 return ExprError(); 3345 3346 // Build the default argument expression. 3347 return Owned(CXXDefaultArgExpr::Create(Context, CallLoc, Param, 3348 Result.takeAs<Expr>())); 3349 } 3350 3351 // If the default expression creates temporaries, we need to 3352 // push them to the current stack of expression temporaries so they'll 3353 // be properly destroyed. 3354 // FIXME: We should really be rebuilding the default argument with new 3355 // bound temporaries; see the comment in PR5810. 3356 for (unsigned i = 0, e = Param->getNumDefaultArgTemporaries(); i != e; ++i) 3357 ExprTemporaries.push_back(Param->getDefaultArgTemporary(i)); 3358 } 3359 3360 // We already type-checked the argument, so we know it works. 3361 return Owned(CXXDefaultArgExpr::Create(Context, CallLoc, Param)); 3362} 3363 3364/// ConvertArgumentsForCall - Converts the arguments specified in 3365/// Args/NumArgs to the parameter types of the function FDecl with 3366/// function prototype Proto. Call is the call expression itself, and 3367/// Fn is the function expression. For a C++ member function, this 3368/// routine does not attempt to convert the object argument. Returns 3369/// true if the call is ill-formed. 3370bool 3371Sema::ConvertArgumentsForCall(CallExpr *Call, Expr *Fn, 3372 FunctionDecl *FDecl, 3373 const FunctionProtoType *Proto, 3374 Expr **Args, unsigned NumArgs, 3375 SourceLocation RParenLoc) { 3376 // C99 6.5.2.2p7 - the arguments are implicitly converted, as if by 3377 // assignment, to the types of the corresponding parameter, ... 3378 unsigned NumArgsInProto = Proto->getNumArgs(); 3379 bool Invalid = false; 3380 3381 // If too few arguments are available (and we don't have default 3382 // arguments for the remaining parameters), don't make the call. 3383 if (NumArgs < NumArgsInProto) { 3384 if (!FDecl || NumArgs < FDecl->getMinRequiredArguments()) 3385 return Diag(RParenLoc, diag::err_typecheck_call_too_few_args) 3386 << Fn->getType()->isBlockPointerType() 3387 << NumArgsInProto << NumArgs << Fn->getSourceRange(); 3388 Call->setNumArgs(Context, NumArgsInProto); 3389 } 3390 3391 // If too many are passed and not variadic, error on the extras and drop 3392 // them. 3393 if (NumArgs > NumArgsInProto) { 3394 if (!Proto->isVariadic()) { 3395 Diag(Args[NumArgsInProto]->getLocStart(), 3396 diag::err_typecheck_call_too_many_args) 3397 << Fn->getType()->isBlockPointerType() 3398 << NumArgsInProto << NumArgs << Fn->getSourceRange() 3399 << SourceRange(Args[NumArgsInProto]->getLocStart(), 3400 Args[NumArgs-1]->getLocEnd()); 3401 // This deletes the extra arguments. 3402 Call->setNumArgs(Context, NumArgsInProto); 3403 return true; 3404 } 3405 } 3406 llvm::SmallVector<Expr *, 8> AllArgs; 3407 VariadicCallType CallType = 3408 Proto->isVariadic() ? VariadicFunction : VariadicDoesNotApply; 3409 if (Fn->getType()->isBlockPointerType()) 3410 CallType = VariadicBlock; // Block 3411 else if (isa<MemberExpr>(Fn)) 3412 CallType = VariadicMethod; 3413 Invalid = GatherArgumentsForCall(Call->getSourceRange().getBegin(), FDecl, 3414 Proto, 0, Args, NumArgs, AllArgs, CallType); 3415 if (Invalid) 3416 return true; 3417 unsigned TotalNumArgs = AllArgs.size(); 3418 for (unsigned i = 0; i < TotalNumArgs; ++i) 3419 Call->setArg(i, AllArgs[i]); 3420 3421 return false; 3422} 3423 3424bool Sema::GatherArgumentsForCall(SourceLocation CallLoc, 3425 FunctionDecl *FDecl, 3426 const FunctionProtoType *Proto, 3427 unsigned FirstProtoArg, 3428 Expr **Args, unsigned NumArgs, 3429 llvm::SmallVector<Expr *, 8> &AllArgs, 3430 VariadicCallType CallType) { 3431 unsigned NumArgsInProto = Proto->getNumArgs(); 3432 unsigned NumArgsToCheck = NumArgs; 3433 bool Invalid = false; 3434 if (NumArgs != NumArgsInProto) 3435 // Use default arguments for missing arguments 3436 NumArgsToCheck = NumArgsInProto; 3437 unsigned ArgIx = 0; 3438 // Continue to check argument types (even if we have too few/many args). 3439 for (unsigned i = FirstProtoArg; i != NumArgsToCheck; i++) { 3440 QualType ProtoArgType = Proto->getArgType(i); 3441 3442 Expr *Arg; 3443 if (ArgIx < NumArgs) { 3444 Arg = Args[ArgIx++]; 3445 3446 if (RequireCompleteType(Arg->getSourceRange().getBegin(), 3447 ProtoArgType, 3448 PDiag(diag::err_call_incomplete_argument) 3449 << Arg->getSourceRange())) 3450 return true; 3451 3452 // Pass the argument 3453 ParmVarDecl *Param = 0; 3454 if (FDecl && i < FDecl->getNumParams()) 3455 Param = FDecl->getParamDecl(i); 3456 3457 3458 InitializedEntity Entity = 3459 Param? InitializedEntity::InitializeParameter(Param) 3460 : InitializedEntity::InitializeParameter(ProtoArgType); 3461 OwningExprResult ArgE = PerformCopyInitialization(Entity, 3462 SourceLocation(), 3463 Owned(Arg)); 3464 if (ArgE.isInvalid()) 3465 return true; 3466 3467 Arg = ArgE.takeAs<Expr>(); 3468 } else { 3469 ParmVarDecl *Param = FDecl->getParamDecl(i); 3470 3471 OwningExprResult ArgExpr = 3472 BuildCXXDefaultArgExpr(CallLoc, FDecl, Param); 3473 if (ArgExpr.isInvalid()) 3474 return true; 3475 3476 Arg = ArgExpr.takeAs<Expr>(); 3477 } 3478 AllArgs.push_back(Arg); 3479 } 3480 3481 // If this is a variadic call, handle args passed through "...". 3482 if (CallType != VariadicDoesNotApply) { 3483 // Promote the arguments (C99 6.5.2.2p7). 3484 for (unsigned i = ArgIx; i != NumArgs; ++i) { 3485 Expr *Arg = Args[i]; 3486 Invalid |= DefaultVariadicArgumentPromotion(Arg, CallType, FDecl); 3487 AllArgs.push_back(Arg); 3488 } 3489 } 3490 return Invalid; 3491} 3492 3493/// ActOnCallExpr - Handle a call to Fn with the specified array of arguments. 3494/// This provides the location of the left/right parens and a list of comma 3495/// locations. 3496Action::OwningExprResult 3497Sema::ActOnCallExpr(Scope *S, ExprArg fn, SourceLocation LParenLoc, 3498 MultiExprArg args, 3499 SourceLocation *CommaLocs, SourceLocation RParenLoc) { 3500 unsigned NumArgs = args.size(); 3501 3502 // Since this might be a postfix expression, get rid of ParenListExprs. 3503 fn = MaybeConvertParenListExprToParenExpr(S, move(fn)); 3504 3505 Expr *Fn = fn.takeAs<Expr>(); 3506 Expr **Args = reinterpret_cast<Expr**>(args.release()); 3507 assert(Fn && "no function call expression"); 3508 3509 if (getLangOptions().CPlusPlus) { 3510 // If this is a pseudo-destructor expression, build the call immediately. 3511 if (isa<CXXPseudoDestructorExpr>(Fn)) { 3512 if (NumArgs > 0) { 3513 // Pseudo-destructor calls should not have any arguments. 3514 Diag(Fn->getLocStart(), diag::err_pseudo_dtor_call_with_args) 3515 << FixItHint::CreateRemoval( 3516 SourceRange(Args[0]->getLocStart(), 3517 Args[NumArgs-1]->getLocEnd())); 3518 3519 for (unsigned I = 0; I != NumArgs; ++I) 3520 Args[I]->Destroy(Context); 3521 3522 NumArgs = 0; 3523 } 3524 3525 return Owned(new (Context) CallExpr(Context, Fn, 0, 0, Context.VoidTy, 3526 RParenLoc)); 3527 } 3528 3529 // Determine whether this is a dependent call inside a C++ template, 3530 // in which case we won't do any semantic analysis now. 3531 // FIXME: Will need to cache the results of name lookup (including ADL) in 3532 // Fn. 3533 bool Dependent = false; 3534 if (Fn->isTypeDependent()) 3535 Dependent = true; 3536 else if (Expr::hasAnyTypeDependentArguments(Args, NumArgs)) 3537 Dependent = true; 3538 3539 if (Dependent) 3540 return Owned(new (Context) CallExpr(Context, Fn, Args, NumArgs, 3541 Context.DependentTy, RParenLoc)); 3542 3543 // Determine whether this is a call to an object (C++ [over.call.object]). 3544 if (Fn->getType()->isRecordType()) 3545 return Owned(BuildCallToObjectOfClassType(S, Fn, LParenLoc, Args, NumArgs, 3546 CommaLocs, RParenLoc)); 3547 3548 Expr *NakedFn = Fn->IgnoreParens(); 3549 3550 // Determine whether this is a call to an unresolved member function. 3551 if (UnresolvedMemberExpr *MemE = dyn_cast<UnresolvedMemberExpr>(NakedFn)) { 3552 // If lookup was unresolved but not dependent (i.e. didn't find 3553 // an unresolved using declaration), it has to be an overloaded 3554 // function set, which means it must contain either multiple 3555 // declarations (all methods or method templates) or a single 3556 // method template. 3557 assert((MemE->getNumDecls() > 1) || 3558 isa<FunctionTemplateDecl>( 3559 (*MemE->decls_begin())->getUnderlyingDecl())); 3560 (void)MemE; 3561 3562 return BuildCallToMemberFunction(S, Fn, LParenLoc, Args, NumArgs, 3563 CommaLocs, RParenLoc); 3564 } 3565 3566 // Determine whether this is a call to a member function. 3567 if (MemberExpr *MemExpr = dyn_cast<MemberExpr>(NakedFn)) { 3568 NamedDecl *MemDecl = MemExpr->getMemberDecl(); 3569 if (isa<CXXMethodDecl>(MemDecl)) 3570 return BuildCallToMemberFunction(S, Fn, LParenLoc, Args, NumArgs, 3571 CommaLocs, RParenLoc); 3572 } 3573 3574 // Determine whether this is a call to a pointer-to-member function. 3575 if (BinaryOperator *BO = dyn_cast<BinaryOperator>(NakedFn)) { 3576 if (BO->getOpcode() == BinaryOperator::PtrMemD || 3577 BO->getOpcode() == BinaryOperator::PtrMemI) { 3578 if (const FunctionProtoType *FPT 3579 = BO->getType()->getAs<FunctionProtoType>()) { 3580 QualType ResultTy = FPT->getResultType().getNonReferenceType(); 3581 3582 ExprOwningPtr<CXXMemberCallExpr> 3583 TheCall(this, new (Context) CXXMemberCallExpr(Context, BO, Args, 3584 NumArgs, ResultTy, 3585 RParenLoc)); 3586 3587 if (CheckCallReturnType(FPT->getResultType(), 3588 BO->getRHS()->getSourceRange().getBegin(), 3589 TheCall.get(), 0)) 3590 return ExprError(); 3591 3592 if (ConvertArgumentsForCall(&*TheCall, BO, 0, FPT, Args, NumArgs, 3593 RParenLoc)) 3594 return ExprError(); 3595 3596 return Owned(MaybeBindToTemporary(TheCall.release()).release()); 3597 } 3598 return ExprError(Diag(Fn->getLocStart(), 3599 diag::err_typecheck_call_not_function) 3600 << Fn->getType() << Fn->getSourceRange()); 3601 } 3602 } 3603 } 3604 3605 // If we're directly calling a function, get the appropriate declaration. 3606 // Also, in C++, keep track of whether we should perform argument-dependent 3607 // lookup and whether there were any explicitly-specified template arguments. 3608 3609 Expr *NakedFn = Fn->IgnoreParens(); 3610 if (isa<UnresolvedLookupExpr>(NakedFn)) { 3611 UnresolvedLookupExpr *ULE = cast<UnresolvedLookupExpr>(NakedFn); 3612 return BuildOverloadedCallExpr(S, Fn, ULE, LParenLoc, Args, NumArgs, 3613 CommaLocs, RParenLoc); 3614 } 3615 3616 NamedDecl *NDecl = 0; 3617 if (isa<DeclRefExpr>(NakedFn)) 3618 NDecl = cast<DeclRefExpr>(NakedFn)->getDecl(); 3619 3620 return BuildResolvedCallExpr(Fn, NDecl, LParenLoc, Args, NumArgs, RParenLoc); 3621} 3622 3623/// BuildResolvedCallExpr - Build a call to a resolved expression, 3624/// i.e. an expression not of \p OverloadTy. The expression should 3625/// unary-convert to an expression of function-pointer or 3626/// block-pointer type. 3627/// 3628/// \param NDecl the declaration being called, if available 3629Sema::OwningExprResult 3630Sema::BuildResolvedCallExpr(Expr *Fn, NamedDecl *NDecl, 3631 SourceLocation LParenLoc, 3632 Expr **Args, unsigned NumArgs, 3633 SourceLocation RParenLoc) { 3634 FunctionDecl *FDecl = dyn_cast_or_null<FunctionDecl>(NDecl); 3635 3636 // Promote the function operand. 3637 UsualUnaryConversions(Fn); 3638 3639 // Make the call expr early, before semantic checks. This guarantees cleanup 3640 // of arguments and function on error. 3641 ExprOwningPtr<CallExpr> TheCall(this, new (Context) CallExpr(Context, Fn, 3642 Args, NumArgs, 3643 Context.BoolTy, 3644 RParenLoc)); 3645 3646 const FunctionType *FuncT; 3647 if (!Fn->getType()->isBlockPointerType()) { 3648 // C99 6.5.2.2p1 - "The expression that denotes the called function shall 3649 // have type pointer to function". 3650 const PointerType *PT = Fn->getType()->getAs<PointerType>(); 3651 if (PT == 0) 3652 return ExprError(Diag(LParenLoc, diag::err_typecheck_call_not_function) 3653 << Fn->getType() << Fn->getSourceRange()); 3654 FuncT = PT->getPointeeType()->getAs<FunctionType>(); 3655 } else { // This is a block call. 3656 FuncT = Fn->getType()->getAs<BlockPointerType>()->getPointeeType()-> 3657 getAs<FunctionType>(); 3658 } 3659 if (FuncT == 0) 3660 return ExprError(Diag(LParenLoc, diag::err_typecheck_call_not_function) 3661 << Fn->getType() << Fn->getSourceRange()); 3662 3663 // Check for a valid return type 3664 if (CheckCallReturnType(FuncT->getResultType(), 3665 Fn->getSourceRange().getBegin(), TheCall.get(), 3666 FDecl)) 3667 return ExprError(); 3668 3669 // We know the result type of the call, set it. 3670 TheCall->setType(FuncT->getResultType().getNonReferenceType()); 3671 3672 if (const FunctionProtoType *Proto = dyn_cast<FunctionProtoType>(FuncT)) { 3673 if (ConvertArgumentsForCall(&*TheCall, Fn, FDecl, Proto, Args, NumArgs, 3674 RParenLoc)) 3675 return ExprError(); 3676 } else { 3677 assert(isa<FunctionNoProtoType>(FuncT) && "Unknown FunctionType!"); 3678 3679 if (FDecl) { 3680 // Check if we have too few/too many template arguments, based 3681 // on our knowledge of the function definition. 3682 const FunctionDecl *Def = 0; 3683 if (FDecl->hasBody(Def) && NumArgs != Def->param_size()) { 3684 const FunctionProtoType *Proto = 3685 Def->getType()->getAs<FunctionProtoType>(); 3686 if (!Proto || !(Proto->isVariadic() && NumArgs >= Def->param_size())) { 3687 Diag(RParenLoc, diag::warn_call_wrong_number_of_arguments) 3688 << (NumArgs > Def->param_size()) << FDecl << Fn->getSourceRange(); 3689 } 3690 } 3691 } 3692 3693 // Promote the arguments (C99 6.5.2.2p6). 3694 for (unsigned i = 0; i != NumArgs; i++) { 3695 Expr *Arg = Args[i]; 3696 DefaultArgumentPromotion(Arg); 3697 if (RequireCompleteType(Arg->getSourceRange().getBegin(), 3698 Arg->getType(), 3699 PDiag(diag::err_call_incomplete_argument) 3700 << Arg->getSourceRange())) 3701 return ExprError(); 3702 TheCall->setArg(i, Arg); 3703 } 3704 } 3705 3706 if (CXXMethodDecl *Method = dyn_cast_or_null<CXXMethodDecl>(FDecl)) 3707 if (!Method->isStatic()) 3708 return ExprError(Diag(LParenLoc, diag::err_member_call_without_object) 3709 << Fn->getSourceRange()); 3710 3711 // Check for sentinels 3712 if (NDecl) 3713 DiagnoseSentinelCalls(NDecl, LParenLoc, Args, NumArgs); 3714 3715 // Do special checking on direct calls to functions. 3716 if (FDecl) { 3717 if (CheckFunctionCall(FDecl, TheCall.get())) 3718 return ExprError(); 3719 3720 if (unsigned BuiltinID = FDecl->getBuiltinID()) 3721 return CheckBuiltinFunctionCall(BuiltinID, TheCall.take()); 3722 } else if (NDecl) { 3723 if (CheckBlockCall(NDecl, TheCall.get())) 3724 return ExprError(); 3725 } 3726 3727 return MaybeBindToTemporary(TheCall.take()); 3728} 3729 3730Action::OwningExprResult 3731Sema::ActOnCompoundLiteral(SourceLocation LParenLoc, TypeTy *Ty, 3732 SourceLocation RParenLoc, ExprArg InitExpr) { 3733 assert((Ty != 0) && "ActOnCompoundLiteral(): missing type"); 3734 // FIXME: put back this assert when initializers are worked out. 3735 //assert((InitExpr != 0) && "ActOnCompoundLiteral(): missing expression"); 3736 3737 TypeSourceInfo *TInfo; 3738 QualType literalType = GetTypeFromParser(Ty, &TInfo); 3739 if (!TInfo) 3740 TInfo = Context.getTrivialTypeSourceInfo(literalType); 3741 3742 return BuildCompoundLiteralExpr(LParenLoc, TInfo, RParenLoc, move(InitExpr)); 3743} 3744 3745Action::OwningExprResult 3746Sema::BuildCompoundLiteralExpr(SourceLocation LParenLoc, TypeSourceInfo *TInfo, 3747 SourceLocation RParenLoc, ExprArg InitExpr) { 3748 QualType literalType = TInfo->getType(); 3749 Expr *literalExpr = static_cast<Expr*>(InitExpr.get()); 3750 3751 if (literalType->isArrayType()) { 3752 if (literalType->isVariableArrayType()) 3753 return ExprError(Diag(LParenLoc, diag::err_variable_object_no_init) 3754 << SourceRange(LParenLoc, literalExpr->getSourceRange().getEnd())); 3755 } else if (!literalType->isDependentType() && 3756 RequireCompleteType(LParenLoc, literalType, 3757 PDiag(diag::err_typecheck_decl_incomplete_type) 3758 << SourceRange(LParenLoc, 3759 literalExpr->getSourceRange().getEnd()))) 3760 return ExprError(); 3761 3762 InitializedEntity Entity 3763 = InitializedEntity::InitializeTemporary(literalType); 3764 InitializationKind Kind 3765 = InitializationKind::CreateCast(SourceRange(LParenLoc, RParenLoc), 3766 /*IsCStyleCast=*/true); 3767 InitializationSequence InitSeq(*this, Entity, Kind, &literalExpr, 1); 3768 OwningExprResult Result = InitSeq.Perform(*this, Entity, Kind, 3769 MultiExprArg(*this, (void**)&literalExpr, 1), 3770 &literalType); 3771 if (Result.isInvalid()) 3772 return ExprError(); 3773 InitExpr.release(); 3774 literalExpr = static_cast<Expr*>(Result.get()); 3775 3776 bool isFileScope = getCurFunctionOrMethodDecl() == 0; 3777 if (isFileScope) { // 6.5.2.5p3 3778 if (CheckForConstantInitializer(literalExpr, literalType)) 3779 return ExprError(); 3780 } 3781 3782 Result.release(); 3783 3784 return Owned(new (Context) CompoundLiteralExpr(LParenLoc, TInfo, literalType, 3785 literalExpr, isFileScope)); 3786} 3787 3788Action::OwningExprResult 3789Sema::ActOnInitList(SourceLocation LBraceLoc, MultiExprArg initlist, 3790 SourceLocation RBraceLoc) { 3791 unsigned NumInit = initlist.size(); 3792 Expr **InitList = reinterpret_cast<Expr**>(initlist.release()); 3793 3794 // Semantic analysis for initializers is done by ActOnDeclarator() and 3795 // CheckInitializer() - it requires knowledge of the object being intialized. 3796 3797 InitListExpr *E = new (Context) InitListExpr(Context, LBraceLoc, InitList, 3798 NumInit, RBraceLoc); 3799 E->setType(Context.VoidTy); // FIXME: just a place holder for now. 3800 return Owned(E); 3801} 3802 3803static CastExpr::CastKind getScalarCastKind(ASTContext &Context, 3804 QualType SrcTy, QualType DestTy) { 3805 if (Context.hasSameUnqualifiedType(SrcTy, DestTy)) 3806 return CastExpr::CK_NoOp; 3807 3808 if (SrcTy->hasPointerRepresentation()) { 3809 if (DestTy->hasPointerRepresentation()) 3810 return DestTy->isObjCObjectPointerType() ? 3811 CastExpr::CK_AnyPointerToObjCPointerCast : 3812 CastExpr::CK_BitCast; 3813 if (DestTy->isIntegerType()) 3814 return CastExpr::CK_PointerToIntegral; 3815 } 3816 3817 if (SrcTy->isIntegerType()) { 3818 if (DestTy->isIntegerType()) 3819 return CastExpr::CK_IntegralCast; 3820 if (DestTy->hasPointerRepresentation()) 3821 return CastExpr::CK_IntegralToPointer; 3822 if (DestTy->isRealFloatingType()) 3823 return CastExpr::CK_IntegralToFloating; 3824 } 3825 3826 if (SrcTy->isRealFloatingType()) { 3827 if (DestTy->isRealFloatingType()) 3828 return CastExpr::CK_FloatingCast; 3829 if (DestTy->isIntegerType()) 3830 return CastExpr::CK_FloatingToIntegral; 3831 } 3832 3833 // FIXME: Assert here. 3834 // assert(false && "Unhandled cast combination!"); 3835 return CastExpr::CK_Unknown; 3836} 3837 3838/// CheckCastTypes - Check type constraints for casting between types. 3839bool Sema::CheckCastTypes(SourceRange TyR, QualType castType, Expr *&castExpr, 3840 CastExpr::CastKind& Kind, 3841 CXXBaseSpecifierArray &BasePath, 3842 bool FunctionalStyle) { 3843 if (getLangOptions().CPlusPlus) 3844 return CXXCheckCStyleCast(TyR, castType, castExpr, Kind, BasePath, 3845 FunctionalStyle); 3846 3847 DefaultFunctionArrayLvalueConversion(castExpr); 3848 3849 // C99 6.5.4p2: the cast type needs to be void or scalar and the expression 3850 // type needs to be scalar. 3851 if (castType->isVoidType()) { 3852 // Cast to void allows any expr type. 3853 Kind = CastExpr::CK_ToVoid; 3854 return false; 3855 } 3856 3857 if (!castType->isScalarType() && !castType->isVectorType()) { 3858 if (Context.hasSameUnqualifiedType(castType, castExpr->getType()) && 3859 (castType->isStructureType() || castType->isUnionType())) { 3860 // GCC struct/union extension: allow cast to self. 3861 // FIXME: Check that the cast destination type is complete. 3862 Diag(TyR.getBegin(), diag::ext_typecheck_cast_nonscalar) 3863 << castType << castExpr->getSourceRange(); 3864 Kind = CastExpr::CK_NoOp; 3865 return false; 3866 } 3867 3868 if (castType->isUnionType()) { 3869 // GCC cast to union extension 3870 RecordDecl *RD = castType->getAs<RecordType>()->getDecl(); 3871 RecordDecl::field_iterator Field, FieldEnd; 3872 for (Field = RD->field_begin(), FieldEnd = RD->field_end(); 3873 Field != FieldEnd; ++Field) { 3874 if (Context.hasSameUnqualifiedType(Field->getType(), 3875 castExpr->getType())) { 3876 Diag(TyR.getBegin(), diag::ext_typecheck_cast_to_union) 3877 << castExpr->getSourceRange(); 3878 break; 3879 } 3880 } 3881 if (Field == FieldEnd) 3882 return Diag(TyR.getBegin(), diag::err_typecheck_cast_to_union_no_type) 3883 << castExpr->getType() << castExpr->getSourceRange(); 3884 Kind = CastExpr::CK_ToUnion; 3885 return false; 3886 } 3887 3888 // Reject any other conversions to non-scalar types. 3889 return Diag(TyR.getBegin(), diag::err_typecheck_cond_expect_scalar) 3890 << castType << castExpr->getSourceRange(); 3891 } 3892 3893 if (!castExpr->getType()->isScalarType() && 3894 !castExpr->getType()->isVectorType()) { 3895 return Diag(castExpr->getLocStart(), 3896 diag::err_typecheck_expect_scalar_operand) 3897 << castExpr->getType() << castExpr->getSourceRange(); 3898 } 3899 3900 if (castType->isExtVectorType()) 3901 return CheckExtVectorCast(TyR, castType, castExpr, Kind); 3902 3903 if (castType->isVectorType()) 3904 return CheckVectorCast(TyR, castType, castExpr->getType(), Kind); 3905 if (castExpr->getType()->isVectorType()) 3906 return CheckVectorCast(TyR, castExpr->getType(), castType, Kind); 3907 3908 if (isa<ObjCSelectorExpr>(castExpr)) 3909 return Diag(castExpr->getLocStart(), diag::err_cast_selector_expr); 3910 3911 if (!castType->isArithmeticType()) { 3912 QualType castExprType = castExpr->getType(); 3913 if (!castExprType->isIntegralType(Context) && 3914 castExprType->isArithmeticType()) 3915 return Diag(castExpr->getLocStart(), 3916 diag::err_cast_pointer_from_non_pointer_int) 3917 << castExprType << castExpr->getSourceRange(); 3918 } else if (!castExpr->getType()->isArithmeticType()) { 3919 if (!castType->isIntegralType(Context) && castType->isArithmeticType()) 3920 return Diag(castExpr->getLocStart(), 3921 diag::err_cast_pointer_to_non_pointer_int) 3922 << castType << castExpr->getSourceRange(); 3923 } 3924 3925 Kind = getScalarCastKind(Context, castExpr->getType(), castType); 3926 return false; 3927} 3928 3929bool Sema::CheckVectorCast(SourceRange R, QualType VectorTy, QualType Ty, 3930 CastExpr::CastKind &Kind) { 3931 assert(VectorTy->isVectorType() && "Not a vector type!"); 3932 3933 if (Ty->isVectorType() || Ty->isIntegerType()) { 3934 if (Context.getTypeSize(VectorTy) != Context.getTypeSize(Ty)) 3935 return Diag(R.getBegin(), 3936 Ty->isVectorType() ? 3937 diag::err_invalid_conversion_between_vectors : 3938 diag::err_invalid_conversion_between_vector_and_integer) 3939 << VectorTy << Ty << R; 3940 } else 3941 return Diag(R.getBegin(), 3942 diag::err_invalid_conversion_between_vector_and_scalar) 3943 << VectorTy << Ty << R; 3944 3945 Kind = CastExpr::CK_BitCast; 3946 return false; 3947} 3948 3949bool Sema::CheckExtVectorCast(SourceRange R, QualType DestTy, Expr *&CastExpr, 3950 CastExpr::CastKind &Kind) { 3951 assert(DestTy->isExtVectorType() && "Not an extended vector type!"); 3952 3953 QualType SrcTy = CastExpr->getType(); 3954 3955 // If SrcTy is a VectorType, the total size must match to explicitly cast to 3956 // an ExtVectorType. 3957 if (SrcTy->isVectorType()) { 3958 if (Context.getTypeSize(DestTy) != Context.getTypeSize(SrcTy)) 3959 return Diag(R.getBegin(),diag::err_invalid_conversion_between_ext_vectors) 3960 << DestTy << SrcTy << R; 3961 Kind = CastExpr::CK_BitCast; 3962 return false; 3963 } 3964 3965 // All non-pointer scalars can be cast to ExtVector type. The appropriate 3966 // conversion will take place first from scalar to elt type, and then 3967 // splat from elt type to vector. 3968 if (SrcTy->isPointerType()) 3969 return Diag(R.getBegin(), 3970 diag::err_invalid_conversion_between_vector_and_scalar) 3971 << DestTy << SrcTy << R; 3972 3973 QualType DestElemTy = DestTy->getAs<ExtVectorType>()->getElementType(); 3974 ImpCastExprToType(CastExpr, DestElemTy, 3975 getScalarCastKind(Context, SrcTy, DestElemTy)); 3976 3977 Kind = CastExpr::CK_VectorSplat; 3978 return false; 3979} 3980 3981Action::OwningExprResult 3982Sema::ActOnCastExpr(Scope *S, SourceLocation LParenLoc, TypeTy *Ty, 3983 SourceLocation RParenLoc, ExprArg Op) { 3984 assert((Ty != 0) && (Op.get() != 0) && 3985 "ActOnCastExpr(): missing type or expr"); 3986 3987 TypeSourceInfo *castTInfo; 3988 QualType castType = GetTypeFromParser(Ty, &castTInfo); 3989 if (!castTInfo) 3990 castTInfo = Context.getTrivialTypeSourceInfo(castType); 3991 3992 // If the Expr being casted is a ParenListExpr, handle it specially. 3993 Expr *castExpr = (Expr *)Op.get(); 3994 if (isa<ParenListExpr>(castExpr)) 3995 return ActOnCastOfParenListExpr(S, LParenLoc, RParenLoc, move(Op), 3996 castTInfo); 3997 3998 return BuildCStyleCastExpr(LParenLoc, castTInfo, RParenLoc, move(Op)); 3999} 4000 4001Action::OwningExprResult 4002Sema::BuildCStyleCastExpr(SourceLocation LParenLoc, TypeSourceInfo *Ty, 4003 SourceLocation RParenLoc, ExprArg Op) { 4004 Expr *castExpr = static_cast<Expr*>(Op.get()); 4005 4006 CastExpr::CastKind Kind = CastExpr::CK_Unknown; 4007 CXXBaseSpecifierArray BasePath; 4008 if (CheckCastTypes(SourceRange(LParenLoc, RParenLoc), Ty->getType(), castExpr, 4009 Kind, BasePath)) 4010 return ExprError(); 4011 4012 Op.release(); 4013 return Owned(new (Context) CStyleCastExpr(Ty->getType().getNonReferenceType(), 4014 Kind, castExpr, BasePath, Ty, 4015 LParenLoc, RParenLoc)); 4016} 4017 4018/// This is not an AltiVec-style cast, so turn the ParenListExpr into a sequence 4019/// of comma binary operators. 4020Action::OwningExprResult 4021Sema::MaybeConvertParenListExprToParenExpr(Scope *S, ExprArg EA) { 4022 Expr *expr = EA.takeAs<Expr>(); 4023 ParenListExpr *E = dyn_cast<ParenListExpr>(expr); 4024 if (!E) 4025 return Owned(expr); 4026 4027 OwningExprResult Result(*this, E->getExpr(0)); 4028 4029 for (unsigned i = 1, e = E->getNumExprs(); i != e && !Result.isInvalid(); ++i) 4030 Result = ActOnBinOp(S, E->getExprLoc(), tok::comma, move(Result), 4031 Owned(E->getExpr(i))); 4032 4033 return ActOnParenExpr(E->getLParenLoc(), E->getRParenLoc(), move(Result)); 4034} 4035 4036Action::OwningExprResult 4037Sema::ActOnCastOfParenListExpr(Scope *S, SourceLocation LParenLoc, 4038 SourceLocation RParenLoc, ExprArg Op, 4039 TypeSourceInfo *TInfo) { 4040 ParenListExpr *PE = (ParenListExpr *)Op.get(); 4041 QualType Ty = TInfo->getType(); 4042 bool isAltiVecLiteral = false; 4043 4044 // Check for an altivec literal, 4045 // i.e. all the elements are integer constants. 4046 if (getLangOptions().AltiVec && Ty->isVectorType()) { 4047 if (PE->getNumExprs() == 0) { 4048 Diag(PE->getExprLoc(), diag::err_altivec_empty_initializer); 4049 return ExprError(); 4050 } 4051 if (PE->getNumExprs() == 1) { 4052 if (!PE->getExpr(0)->getType()->isVectorType()) 4053 isAltiVecLiteral = true; 4054 } 4055 else 4056 isAltiVecLiteral = true; 4057 } 4058 4059 // If this is an altivec initializer, '(' type ')' '(' init, ..., init ')' 4060 // then handle it as such. 4061 if (isAltiVecLiteral) { 4062 llvm::SmallVector<Expr *, 8> initExprs; 4063 for (unsigned i = 0, e = PE->getNumExprs(); i != e; ++i) 4064 initExprs.push_back(PE->getExpr(i)); 4065 4066 // FIXME: This means that pretty-printing the final AST will produce curly 4067 // braces instead of the original commas. 4068 Op.release(); 4069 InitListExpr *E = new (Context) InitListExpr(Context, LParenLoc, 4070 &initExprs[0], 4071 initExprs.size(), RParenLoc); 4072 E->setType(Ty); 4073 return BuildCompoundLiteralExpr(LParenLoc, TInfo, RParenLoc, Owned(E)); 4074 } else { 4075 // This is not an AltiVec-style cast, so turn the ParenListExpr into a 4076 // sequence of BinOp comma operators. 4077 Op = MaybeConvertParenListExprToParenExpr(S, move(Op)); 4078 return BuildCStyleCastExpr(LParenLoc, TInfo, RParenLoc, move(Op)); 4079 } 4080} 4081 4082Action::OwningExprResult Sema::ActOnParenOrParenListExpr(SourceLocation L, 4083 SourceLocation R, 4084 MultiExprArg Val, 4085 TypeTy *TypeOfCast) { 4086 unsigned nexprs = Val.size(); 4087 Expr **exprs = reinterpret_cast<Expr**>(Val.release()); 4088 assert((exprs != 0) && "ActOnParenOrParenListExpr() missing expr list"); 4089 Expr *expr; 4090 if (nexprs == 1 && TypeOfCast && !TypeIsVectorType(TypeOfCast)) 4091 expr = new (Context) ParenExpr(L, R, exprs[0]); 4092 else 4093 expr = new (Context) ParenListExpr(Context, L, exprs, nexprs, R); 4094 return Owned(expr); 4095} 4096 4097/// Note that lhs is not null here, even if this is the gnu "x ?: y" extension. 4098/// In that case, lhs = cond. 4099/// C99 6.5.15 4100QualType Sema::CheckConditionalOperands(Expr *&Cond, Expr *&LHS, Expr *&RHS, 4101 SourceLocation QuestionLoc) { 4102 // C++ is sufficiently different to merit its own checker. 4103 if (getLangOptions().CPlusPlus) 4104 return CXXCheckConditionalOperands(Cond, LHS, RHS, QuestionLoc); 4105 4106 UsualUnaryConversions(Cond); 4107 UsualUnaryConversions(LHS); 4108 UsualUnaryConversions(RHS); 4109 QualType CondTy = Cond->getType(); 4110 QualType LHSTy = LHS->getType(); 4111 QualType RHSTy = RHS->getType(); 4112 4113 // first, check the condition. 4114 if (!CondTy->isScalarType()) { // C99 6.5.15p2 4115 Diag(Cond->getLocStart(), diag::err_typecheck_cond_expect_scalar) 4116 << CondTy; 4117 return QualType(); 4118 } 4119 4120 // Now check the two expressions. 4121 if (LHSTy->isVectorType() || RHSTy->isVectorType()) 4122 return CheckVectorOperands(QuestionLoc, LHS, RHS); 4123 4124 // If both operands have arithmetic type, do the usual arithmetic conversions 4125 // to find a common type: C99 6.5.15p3,5. 4126 if (LHSTy->isArithmeticType() && RHSTy->isArithmeticType()) { 4127 UsualArithmeticConversions(LHS, RHS); 4128 return LHS->getType(); 4129 } 4130 4131 // If both operands are the same structure or union type, the result is that 4132 // type. 4133 if (const RecordType *LHSRT = LHSTy->getAs<RecordType>()) { // C99 6.5.15p3 4134 if (const RecordType *RHSRT = RHSTy->getAs<RecordType>()) 4135 if (LHSRT->getDecl() == RHSRT->getDecl()) 4136 // "If both the operands have structure or union type, the result has 4137 // that type." This implies that CV qualifiers are dropped. 4138 return LHSTy.getUnqualifiedType(); 4139 // FIXME: Type of conditional expression must be complete in C mode. 4140 } 4141 4142 // C99 6.5.15p5: "If both operands have void type, the result has void type." 4143 // The following || allows only one side to be void (a GCC-ism). 4144 if (LHSTy->isVoidType() || RHSTy->isVoidType()) { 4145 if (!LHSTy->isVoidType()) 4146 Diag(RHS->getLocStart(), diag::ext_typecheck_cond_one_void) 4147 << RHS->getSourceRange(); 4148 if (!RHSTy->isVoidType()) 4149 Diag(LHS->getLocStart(), diag::ext_typecheck_cond_one_void) 4150 << LHS->getSourceRange(); 4151 ImpCastExprToType(LHS, Context.VoidTy, CastExpr::CK_ToVoid); 4152 ImpCastExprToType(RHS, Context.VoidTy, CastExpr::CK_ToVoid); 4153 return Context.VoidTy; 4154 } 4155 // C99 6.5.15p6 - "if one operand is a null pointer constant, the result has 4156 // the type of the other operand." 4157 if ((LHSTy->isAnyPointerType() || LHSTy->isBlockPointerType()) && 4158 RHS->isNullPointerConstant(Context, Expr::NPC_ValueDependentIsNull)) { 4159 // promote the null to a pointer. 4160 ImpCastExprToType(RHS, LHSTy, CastExpr::CK_Unknown); 4161 return LHSTy; 4162 } 4163 if ((RHSTy->isAnyPointerType() || RHSTy->isBlockPointerType()) && 4164 LHS->isNullPointerConstant(Context, Expr::NPC_ValueDependentIsNull)) { 4165 ImpCastExprToType(LHS, RHSTy, CastExpr::CK_Unknown); 4166 return RHSTy; 4167 } 4168 4169 // All objective-c pointer type analysis is done here. 4170 QualType compositeType = FindCompositeObjCPointerType(LHS, RHS, 4171 QuestionLoc); 4172 if (!compositeType.isNull()) 4173 return compositeType; 4174 4175 4176 // Handle block pointer types. 4177 if (LHSTy->isBlockPointerType() || RHSTy->isBlockPointerType()) { 4178 if (!LHSTy->isBlockPointerType() || !RHSTy->isBlockPointerType()) { 4179 if (LHSTy->isVoidPointerType() || RHSTy->isVoidPointerType()) { 4180 QualType destType = Context.getPointerType(Context.VoidTy); 4181 ImpCastExprToType(LHS, destType, CastExpr::CK_BitCast); 4182 ImpCastExprToType(RHS, destType, CastExpr::CK_BitCast); 4183 return destType; 4184 } 4185 Diag(QuestionLoc, diag::err_typecheck_cond_incompatible_operands) 4186 << LHSTy << RHSTy << LHS->getSourceRange() << RHS->getSourceRange(); 4187 return QualType(); 4188 } 4189 // We have 2 block pointer types. 4190 if (Context.getCanonicalType(LHSTy) == Context.getCanonicalType(RHSTy)) { 4191 // Two identical block pointer types are always compatible. 4192 return LHSTy; 4193 } 4194 // The block pointer types aren't identical, continue checking. 4195 QualType lhptee = LHSTy->getAs<BlockPointerType>()->getPointeeType(); 4196 QualType rhptee = RHSTy->getAs<BlockPointerType>()->getPointeeType(); 4197 4198 if (!Context.typesAreCompatible(lhptee.getUnqualifiedType(), 4199 rhptee.getUnqualifiedType())) { 4200 Diag(QuestionLoc, diag::warn_typecheck_cond_incompatible_pointers) 4201 << LHSTy << RHSTy << LHS->getSourceRange() << RHS->getSourceRange(); 4202 // In this situation, we assume void* type. No especially good 4203 // reason, but this is what gcc does, and we do have to pick 4204 // to get a consistent AST. 4205 QualType incompatTy = Context.getPointerType(Context.VoidTy); 4206 ImpCastExprToType(LHS, incompatTy, CastExpr::CK_BitCast); 4207 ImpCastExprToType(RHS, incompatTy, CastExpr::CK_BitCast); 4208 return incompatTy; 4209 } 4210 // The block pointer types are compatible. 4211 ImpCastExprToType(LHS, LHSTy, CastExpr::CK_BitCast); 4212 ImpCastExprToType(RHS, LHSTy, CastExpr::CK_BitCast); 4213 return LHSTy; 4214 } 4215 4216 // Check constraints for C object pointers types (C99 6.5.15p3,6). 4217 if (LHSTy->isPointerType() && RHSTy->isPointerType()) { 4218 // get the "pointed to" types 4219 QualType lhptee = LHSTy->getAs<PointerType>()->getPointeeType(); 4220 QualType rhptee = RHSTy->getAs<PointerType>()->getPointeeType(); 4221 4222 // ignore qualifiers on void (C99 6.5.15p3, clause 6) 4223 if (lhptee->isVoidType() && rhptee->isIncompleteOrObjectType()) { 4224 // Figure out necessary qualifiers (C99 6.5.15p6) 4225 QualType destPointee 4226 = Context.getQualifiedType(lhptee, rhptee.getQualifiers()); 4227 QualType destType = Context.getPointerType(destPointee); 4228 // Add qualifiers if necessary. 4229 ImpCastExprToType(LHS, destType, CastExpr::CK_NoOp); 4230 // Promote to void*. 4231 ImpCastExprToType(RHS, destType, CastExpr::CK_BitCast); 4232 return destType; 4233 } 4234 if (rhptee->isVoidType() && lhptee->isIncompleteOrObjectType()) { 4235 QualType destPointee 4236 = Context.getQualifiedType(rhptee, lhptee.getQualifiers()); 4237 QualType destType = Context.getPointerType(destPointee); 4238 // Add qualifiers if necessary. 4239 ImpCastExprToType(RHS, destType, CastExpr::CK_NoOp); 4240 // Promote to void*. 4241 ImpCastExprToType(LHS, destType, CastExpr::CK_BitCast); 4242 return destType; 4243 } 4244 4245 if (Context.getCanonicalType(LHSTy) == Context.getCanonicalType(RHSTy)) { 4246 // Two identical pointer types are always compatible. 4247 return LHSTy; 4248 } 4249 if (!Context.typesAreCompatible(lhptee.getUnqualifiedType(), 4250 rhptee.getUnqualifiedType())) { 4251 Diag(QuestionLoc, diag::warn_typecheck_cond_incompatible_pointers) 4252 << LHSTy << RHSTy << LHS->getSourceRange() << RHS->getSourceRange(); 4253 // In this situation, we assume void* type. No especially good 4254 // reason, but this is what gcc does, and we do have to pick 4255 // to get a consistent AST. 4256 QualType incompatTy = Context.getPointerType(Context.VoidTy); 4257 ImpCastExprToType(LHS, incompatTy, CastExpr::CK_BitCast); 4258 ImpCastExprToType(RHS, incompatTy, CastExpr::CK_BitCast); 4259 return incompatTy; 4260 } 4261 // The pointer types are compatible. 4262 // C99 6.5.15p6: If both operands are pointers to compatible types *or* to 4263 // differently qualified versions of compatible types, the result type is 4264 // a pointer to an appropriately qualified version of the *composite* 4265 // type. 4266 // FIXME: Need to calculate the composite type. 4267 // FIXME: Need to add qualifiers 4268 ImpCastExprToType(LHS, LHSTy, CastExpr::CK_BitCast); 4269 ImpCastExprToType(RHS, LHSTy, CastExpr::CK_BitCast); 4270 return LHSTy; 4271 } 4272 4273 // GCC compatibility: soften pointer/integer mismatch. 4274 if (RHSTy->isPointerType() && LHSTy->isIntegerType()) { 4275 Diag(QuestionLoc, diag::warn_typecheck_cond_pointer_integer_mismatch) 4276 << LHSTy << RHSTy << LHS->getSourceRange() << RHS->getSourceRange(); 4277 ImpCastExprToType(LHS, RHSTy, CastExpr::CK_IntegralToPointer); 4278 return RHSTy; 4279 } 4280 if (LHSTy->isPointerType() && RHSTy->isIntegerType()) { 4281 Diag(QuestionLoc, diag::warn_typecheck_cond_pointer_integer_mismatch) 4282 << LHSTy << RHSTy << LHS->getSourceRange() << RHS->getSourceRange(); 4283 ImpCastExprToType(RHS, LHSTy, CastExpr::CK_IntegralToPointer); 4284 return LHSTy; 4285 } 4286 4287 // Otherwise, the operands are not compatible. 4288 Diag(QuestionLoc, diag::err_typecheck_cond_incompatible_operands) 4289 << LHSTy << RHSTy << LHS->getSourceRange() << RHS->getSourceRange(); 4290 return QualType(); 4291} 4292 4293/// FindCompositeObjCPointerType - Helper method to find composite type of 4294/// two objective-c pointer types of the two input expressions. 4295QualType Sema::FindCompositeObjCPointerType(Expr *&LHS, Expr *&RHS, 4296 SourceLocation QuestionLoc) { 4297 QualType LHSTy = LHS->getType(); 4298 QualType RHSTy = RHS->getType(); 4299 4300 // Handle things like Class and struct objc_class*. Here we case the result 4301 // to the pseudo-builtin, because that will be implicitly cast back to the 4302 // redefinition type if an attempt is made to access its fields. 4303 if (LHSTy->isObjCClassType() && 4304 (RHSTy.getDesugaredType() == Context.ObjCClassRedefinitionType)) { 4305 ImpCastExprToType(RHS, LHSTy, CastExpr::CK_BitCast); 4306 return LHSTy; 4307 } 4308 if (RHSTy->isObjCClassType() && 4309 (LHSTy.getDesugaredType() == Context.ObjCClassRedefinitionType)) { 4310 ImpCastExprToType(LHS, RHSTy, CastExpr::CK_BitCast); 4311 return RHSTy; 4312 } 4313 // And the same for struct objc_object* / id 4314 if (LHSTy->isObjCIdType() && 4315 (RHSTy.getDesugaredType() == Context.ObjCIdRedefinitionType)) { 4316 ImpCastExprToType(RHS, LHSTy, CastExpr::CK_BitCast); 4317 return LHSTy; 4318 } 4319 if (RHSTy->isObjCIdType() && 4320 (LHSTy.getDesugaredType() == Context.ObjCIdRedefinitionType)) { 4321 ImpCastExprToType(LHS, RHSTy, CastExpr::CK_BitCast); 4322 return RHSTy; 4323 } 4324 // And the same for struct objc_selector* / SEL 4325 if (Context.isObjCSelType(LHSTy) && 4326 (RHSTy.getDesugaredType() == Context.ObjCSelRedefinitionType)) { 4327 ImpCastExprToType(RHS, LHSTy, CastExpr::CK_BitCast); 4328 return LHSTy; 4329 } 4330 if (Context.isObjCSelType(RHSTy) && 4331 (LHSTy.getDesugaredType() == Context.ObjCSelRedefinitionType)) { 4332 ImpCastExprToType(LHS, RHSTy, CastExpr::CK_BitCast); 4333 return RHSTy; 4334 } 4335 // Check constraints for Objective-C object pointers types. 4336 if (LHSTy->isObjCObjectPointerType() && RHSTy->isObjCObjectPointerType()) { 4337 4338 if (Context.getCanonicalType(LHSTy) == Context.getCanonicalType(RHSTy)) { 4339 // Two identical object pointer types are always compatible. 4340 return LHSTy; 4341 } 4342 const ObjCObjectPointerType *LHSOPT = LHSTy->getAs<ObjCObjectPointerType>(); 4343 const ObjCObjectPointerType *RHSOPT = RHSTy->getAs<ObjCObjectPointerType>(); 4344 QualType compositeType = LHSTy; 4345 4346 // If both operands are interfaces and either operand can be 4347 // assigned to the other, use that type as the composite 4348 // type. This allows 4349 // xxx ? (A*) a : (B*) b 4350 // where B is a subclass of A. 4351 // 4352 // Additionally, as for assignment, if either type is 'id' 4353 // allow silent coercion. Finally, if the types are 4354 // incompatible then make sure to use 'id' as the composite 4355 // type so the result is acceptable for sending messages to. 4356 4357 // FIXME: Consider unifying with 'areComparableObjCPointerTypes'. 4358 // It could return the composite type. 4359 if (Context.canAssignObjCInterfaces(LHSOPT, RHSOPT)) { 4360 compositeType = RHSOPT->isObjCBuiltinType() ? RHSTy : LHSTy; 4361 } else if (Context.canAssignObjCInterfaces(RHSOPT, LHSOPT)) { 4362 compositeType = LHSOPT->isObjCBuiltinType() ? LHSTy : RHSTy; 4363 } else if ((LHSTy->isObjCQualifiedIdType() || 4364 RHSTy->isObjCQualifiedIdType()) && 4365 Context.ObjCQualifiedIdTypesAreCompatible(LHSTy, RHSTy, true)) { 4366 // Need to handle "id<xx>" explicitly. 4367 // GCC allows qualified id and any Objective-C type to devolve to 4368 // id. Currently localizing to here until clear this should be 4369 // part of ObjCQualifiedIdTypesAreCompatible. 4370 compositeType = Context.getObjCIdType(); 4371 } else if (LHSTy->isObjCIdType() || RHSTy->isObjCIdType()) { 4372 compositeType = Context.getObjCIdType(); 4373 } else if (!(compositeType = 4374 Context.areCommonBaseCompatible(LHSOPT, RHSOPT)).isNull()) 4375 ; 4376 else { 4377 Diag(QuestionLoc, diag::ext_typecheck_cond_incompatible_operands) 4378 << LHSTy << RHSTy 4379 << LHS->getSourceRange() << RHS->getSourceRange(); 4380 QualType incompatTy = Context.getObjCIdType(); 4381 ImpCastExprToType(LHS, incompatTy, CastExpr::CK_BitCast); 4382 ImpCastExprToType(RHS, incompatTy, CastExpr::CK_BitCast); 4383 return incompatTy; 4384 } 4385 // The object pointer types are compatible. 4386 ImpCastExprToType(LHS, compositeType, CastExpr::CK_BitCast); 4387 ImpCastExprToType(RHS, compositeType, CastExpr::CK_BitCast); 4388 return compositeType; 4389 } 4390 // Check Objective-C object pointer types and 'void *' 4391 if (LHSTy->isVoidPointerType() && RHSTy->isObjCObjectPointerType()) { 4392 QualType lhptee = LHSTy->getAs<PointerType>()->getPointeeType(); 4393 QualType rhptee = RHSTy->getAs<ObjCObjectPointerType>()->getPointeeType(); 4394 QualType destPointee 4395 = Context.getQualifiedType(lhptee, rhptee.getQualifiers()); 4396 QualType destType = Context.getPointerType(destPointee); 4397 // Add qualifiers if necessary. 4398 ImpCastExprToType(LHS, destType, CastExpr::CK_NoOp); 4399 // Promote to void*. 4400 ImpCastExprToType(RHS, destType, CastExpr::CK_BitCast); 4401 return destType; 4402 } 4403 if (LHSTy->isObjCObjectPointerType() && RHSTy->isVoidPointerType()) { 4404 QualType lhptee = LHSTy->getAs<ObjCObjectPointerType>()->getPointeeType(); 4405 QualType rhptee = RHSTy->getAs<PointerType>()->getPointeeType(); 4406 QualType destPointee 4407 = Context.getQualifiedType(rhptee, lhptee.getQualifiers()); 4408 QualType destType = Context.getPointerType(destPointee); 4409 // Add qualifiers if necessary. 4410 ImpCastExprToType(RHS, destType, CastExpr::CK_NoOp); 4411 // Promote to void*. 4412 ImpCastExprToType(LHS, destType, CastExpr::CK_BitCast); 4413 return destType; 4414 } 4415 return QualType(); 4416} 4417 4418/// ActOnConditionalOp - Parse a ?: operation. Note that 'LHS' may be null 4419/// in the case of a the GNU conditional expr extension. 4420Action::OwningExprResult Sema::ActOnConditionalOp(SourceLocation QuestionLoc, 4421 SourceLocation ColonLoc, 4422 ExprArg Cond, ExprArg LHS, 4423 ExprArg RHS) { 4424 Expr *CondExpr = (Expr *) Cond.get(); 4425 Expr *LHSExpr = (Expr *) LHS.get(), *RHSExpr = (Expr *) RHS.get(); 4426 4427 // If this is the gnu "x ?: y" extension, analyze the types as though the LHS 4428 // was the condition. 4429 bool isLHSNull = LHSExpr == 0; 4430 if (isLHSNull) 4431 LHSExpr = CondExpr; 4432 4433 QualType result = CheckConditionalOperands(CondExpr, LHSExpr, 4434 RHSExpr, QuestionLoc); 4435 if (result.isNull()) 4436 return ExprError(); 4437 4438 Cond.release(); 4439 LHS.release(); 4440 RHS.release(); 4441 return Owned(new (Context) ConditionalOperator(CondExpr, QuestionLoc, 4442 isLHSNull ? 0 : LHSExpr, 4443 ColonLoc, RHSExpr, result)); 4444} 4445 4446// CheckPointerTypesForAssignment - This is a very tricky routine (despite 4447// being closely modeled after the C99 spec:-). The odd characteristic of this 4448// routine is it effectively iqnores the qualifiers on the top level pointee. 4449// This circumvents the usual type rules specified in 6.2.7p1 & 6.7.5.[1-3]. 4450// FIXME: add a couple examples in this comment. 4451Sema::AssignConvertType 4452Sema::CheckPointerTypesForAssignment(QualType lhsType, QualType rhsType) { 4453 QualType lhptee, rhptee; 4454 4455 if ((lhsType->isObjCClassType() && 4456 (rhsType.getDesugaredType() == Context.ObjCClassRedefinitionType)) || 4457 (rhsType->isObjCClassType() && 4458 (lhsType.getDesugaredType() == Context.ObjCClassRedefinitionType))) { 4459 return Compatible; 4460 } 4461 4462 // get the "pointed to" type (ignoring qualifiers at the top level) 4463 lhptee = lhsType->getAs<PointerType>()->getPointeeType(); 4464 rhptee = rhsType->getAs<PointerType>()->getPointeeType(); 4465 4466 // make sure we operate on the canonical type 4467 lhptee = Context.getCanonicalType(lhptee); 4468 rhptee = Context.getCanonicalType(rhptee); 4469 4470 AssignConvertType ConvTy = Compatible; 4471 4472 // C99 6.5.16.1p1: This following citation is common to constraints 4473 // 3 & 4 (below). ...and the type *pointed to* by the left has all the 4474 // qualifiers of the type *pointed to* by the right; 4475 // FIXME: Handle ExtQualType 4476 if (!lhptee.isAtLeastAsQualifiedAs(rhptee)) 4477 ConvTy = CompatiblePointerDiscardsQualifiers; 4478 4479 // C99 6.5.16.1p1 (constraint 4): If one operand is a pointer to an object or 4480 // incomplete type and the other is a pointer to a qualified or unqualified 4481 // version of void... 4482 if (lhptee->isVoidType()) { 4483 if (rhptee->isIncompleteOrObjectType()) 4484 return ConvTy; 4485 4486 // As an extension, we allow cast to/from void* to function pointer. 4487 assert(rhptee->isFunctionType()); 4488 return FunctionVoidPointer; 4489 } 4490 4491 if (rhptee->isVoidType()) { 4492 if (lhptee->isIncompleteOrObjectType()) 4493 return ConvTy; 4494 4495 // As an extension, we allow cast to/from void* to function pointer. 4496 assert(lhptee->isFunctionType()); 4497 return FunctionVoidPointer; 4498 } 4499 // C99 6.5.16.1p1 (constraint 3): both operands are pointers to qualified or 4500 // unqualified versions of compatible types, ... 4501 lhptee = lhptee.getUnqualifiedType(); 4502 rhptee = rhptee.getUnqualifiedType(); 4503 if (!Context.typesAreCompatible(lhptee, rhptee)) { 4504 // Check if the pointee types are compatible ignoring the sign. 4505 // We explicitly check for char so that we catch "char" vs 4506 // "unsigned char" on systems where "char" is unsigned. 4507 if (lhptee->isCharType()) 4508 lhptee = Context.UnsignedCharTy; 4509 else if (lhptee->isSignedIntegerType()) 4510 lhptee = Context.getCorrespondingUnsignedType(lhptee); 4511 4512 if (rhptee->isCharType()) 4513 rhptee = Context.UnsignedCharTy; 4514 else if (rhptee->isSignedIntegerType()) 4515 rhptee = Context.getCorrespondingUnsignedType(rhptee); 4516 4517 if (lhptee == rhptee) { 4518 // Types are compatible ignoring the sign. Qualifier incompatibility 4519 // takes priority over sign incompatibility because the sign 4520 // warning can be disabled. 4521 if (ConvTy != Compatible) 4522 return ConvTy; 4523 return IncompatiblePointerSign; 4524 } 4525 4526 // If we are a multi-level pointer, it's possible that our issue is simply 4527 // one of qualification - e.g. char ** -> const char ** is not allowed. If 4528 // the eventual target type is the same and the pointers have the same 4529 // level of indirection, this must be the issue. 4530 if (lhptee->isPointerType() && rhptee->isPointerType()) { 4531 do { 4532 lhptee = lhptee->getAs<PointerType>()->getPointeeType(); 4533 rhptee = rhptee->getAs<PointerType>()->getPointeeType(); 4534 4535 lhptee = Context.getCanonicalType(lhptee); 4536 rhptee = Context.getCanonicalType(rhptee); 4537 } while (lhptee->isPointerType() && rhptee->isPointerType()); 4538 4539 if (Context.hasSameUnqualifiedType(lhptee, rhptee)) 4540 return IncompatibleNestedPointerQualifiers; 4541 } 4542 4543 // General pointer incompatibility takes priority over qualifiers. 4544 return IncompatiblePointer; 4545 } 4546 return ConvTy; 4547} 4548 4549/// CheckBlockPointerTypesForAssignment - This routine determines whether two 4550/// block pointer types are compatible or whether a block and normal pointer 4551/// are compatible. It is more restrict than comparing two function pointer 4552// types. 4553Sema::AssignConvertType 4554Sema::CheckBlockPointerTypesForAssignment(QualType lhsType, 4555 QualType rhsType) { 4556 QualType lhptee, rhptee; 4557 4558 // get the "pointed to" type (ignoring qualifiers at the top level) 4559 lhptee = lhsType->getAs<BlockPointerType>()->getPointeeType(); 4560 rhptee = rhsType->getAs<BlockPointerType>()->getPointeeType(); 4561 4562 // make sure we operate on the canonical type 4563 lhptee = Context.getCanonicalType(lhptee); 4564 rhptee = Context.getCanonicalType(rhptee); 4565 4566 AssignConvertType ConvTy = Compatible; 4567 4568 // For blocks we enforce that qualifiers are identical. 4569 if (lhptee.getLocalCVRQualifiers() != rhptee.getLocalCVRQualifiers()) 4570 ConvTy = CompatiblePointerDiscardsQualifiers; 4571 4572 if (!getLangOptions().CPlusPlus) { 4573 if (!Context.typesAreBlockPointerCompatible(lhsType, rhsType)) 4574 return IncompatibleBlockPointer; 4575 } 4576 else if (!Context.typesAreCompatible(lhptee, rhptee)) 4577 return IncompatibleBlockPointer; 4578 return ConvTy; 4579} 4580 4581/// CheckObjCPointerTypesForAssignment - Compares two objective-c pointer types 4582/// for assignment compatibility. 4583Sema::AssignConvertType 4584Sema::CheckObjCPointerTypesForAssignment(QualType lhsType, QualType rhsType) { 4585 if (lhsType->isObjCBuiltinType()) { 4586 // Class is not compatible with ObjC object pointers. 4587 if (lhsType->isObjCClassType() && !rhsType->isObjCBuiltinType() && 4588 !rhsType->isObjCQualifiedClassType()) 4589 return IncompatiblePointer; 4590 return Compatible; 4591 } 4592 if (rhsType->isObjCBuiltinType()) { 4593 // Class is not compatible with ObjC object pointers. 4594 if (rhsType->isObjCClassType() && !lhsType->isObjCBuiltinType() && 4595 !lhsType->isObjCQualifiedClassType()) 4596 return IncompatiblePointer; 4597 return Compatible; 4598 } 4599 QualType lhptee = 4600 lhsType->getAs<ObjCObjectPointerType>()->getPointeeType(); 4601 QualType rhptee = 4602 rhsType->getAs<ObjCObjectPointerType>()->getPointeeType(); 4603 // make sure we operate on the canonical type 4604 lhptee = Context.getCanonicalType(lhptee); 4605 rhptee = Context.getCanonicalType(rhptee); 4606 if (!lhptee.isAtLeastAsQualifiedAs(rhptee)) 4607 return CompatiblePointerDiscardsQualifiers; 4608 4609 if (Context.typesAreCompatible(lhsType, rhsType)) 4610 return Compatible; 4611 if (lhsType->isObjCQualifiedIdType() || rhsType->isObjCQualifiedIdType()) 4612 return IncompatibleObjCQualifiedId; 4613 return IncompatiblePointer; 4614} 4615 4616/// CheckAssignmentConstraints (C99 6.5.16) - This routine currently 4617/// has code to accommodate several GCC extensions when type checking 4618/// pointers. Here are some objectionable examples that GCC considers warnings: 4619/// 4620/// int a, *pint; 4621/// short *pshort; 4622/// struct foo *pfoo; 4623/// 4624/// pint = pshort; // warning: assignment from incompatible pointer type 4625/// a = pint; // warning: assignment makes integer from pointer without a cast 4626/// pint = a; // warning: assignment makes pointer from integer without a cast 4627/// pint = pfoo; // warning: assignment from incompatible pointer type 4628/// 4629/// As a result, the code for dealing with pointers is more complex than the 4630/// C99 spec dictates. 4631/// 4632Sema::AssignConvertType 4633Sema::CheckAssignmentConstraints(QualType lhsType, QualType rhsType) { 4634 // Get canonical types. We're not formatting these types, just comparing 4635 // them. 4636 lhsType = Context.getCanonicalType(lhsType).getUnqualifiedType(); 4637 rhsType = Context.getCanonicalType(rhsType).getUnqualifiedType(); 4638 4639 if (lhsType == rhsType) 4640 return Compatible; // Common case: fast path an exact match. 4641 4642 if ((lhsType->isObjCClassType() && 4643 (rhsType.getDesugaredType() == Context.ObjCClassRedefinitionType)) || 4644 (rhsType->isObjCClassType() && 4645 (lhsType.getDesugaredType() == Context.ObjCClassRedefinitionType))) { 4646 return Compatible; 4647 } 4648 4649 // If the left-hand side is a reference type, then we are in a 4650 // (rare!) case where we've allowed the use of references in C, 4651 // e.g., as a parameter type in a built-in function. In this case, 4652 // just make sure that the type referenced is compatible with the 4653 // right-hand side type. The caller is responsible for adjusting 4654 // lhsType so that the resulting expression does not have reference 4655 // type. 4656 if (const ReferenceType *lhsTypeRef = lhsType->getAs<ReferenceType>()) { 4657 if (Context.typesAreCompatible(lhsTypeRef->getPointeeType(), rhsType)) 4658 return Compatible; 4659 return Incompatible; 4660 } 4661 // Allow scalar to ExtVector assignments, and assignments of an ExtVector type 4662 // to the same ExtVector type. 4663 if (lhsType->isExtVectorType()) { 4664 if (rhsType->isExtVectorType()) 4665 return lhsType == rhsType ? Compatible : Incompatible; 4666 if (rhsType->isArithmeticType()) 4667 return Compatible; 4668 } 4669 4670 if (lhsType->isVectorType() || rhsType->isVectorType()) { 4671 // If we are allowing lax vector conversions, and LHS and RHS are both 4672 // vectors, the total size only needs to be the same. This is a bitcast; 4673 // no bits are changed but the result type is different. 4674 if (getLangOptions().LaxVectorConversions && 4675 lhsType->isVectorType() && rhsType->isVectorType()) { 4676 if (Context.getTypeSize(lhsType) == Context.getTypeSize(rhsType)) 4677 return IncompatibleVectors; 4678 } 4679 return Incompatible; 4680 } 4681 4682 if (lhsType->isArithmeticType() && rhsType->isArithmeticType() && 4683 !(getLangOptions().CPlusPlus && lhsType->isEnumeralType())) 4684 return Compatible; 4685 4686 if (isa<PointerType>(lhsType)) { 4687 if (rhsType->isIntegerType()) 4688 return IntToPointer; 4689 4690 if (isa<PointerType>(rhsType)) 4691 return CheckPointerTypesForAssignment(lhsType, rhsType); 4692 4693 // In general, C pointers are not compatible with ObjC object pointers. 4694 if (isa<ObjCObjectPointerType>(rhsType)) { 4695 if (lhsType->isVoidPointerType()) // an exception to the rule. 4696 return Compatible; 4697 return IncompatiblePointer; 4698 } 4699 if (rhsType->getAs<BlockPointerType>()) { 4700 if (lhsType->getAs<PointerType>()->getPointeeType()->isVoidType()) 4701 return Compatible; 4702 4703 // Treat block pointers as objects. 4704 if (getLangOptions().ObjC1 && lhsType->isObjCIdType()) 4705 return Compatible; 4706 } 4707 return Incompatible; 4708 } 4709 4710 if (isa<BlockPointerType>(lhsType)) { 4711 if (rhsType->isIntegerType()) 4712 return IntToBlockPointer; 4713 4714 // Treat block pointers as objects. 4715 if (getLangOptions().ObjC1 && rhsType->isObjCIdType()) 4716 return Compatible; 4717 4718 if (rhsType->isBlockPointerType()) 4719 return CheckBlockPointerTypesForAssignment(lhsType, rhsType); 4720 4721 if (const PointerType *RHSPT = rhsType->getAs<PointerType>()) { 4722 if (RHSPT->getPointeeType()->isVoidType()) 4723 return Compatible; 4724 } 4725 return Incompatible; 4726 } 4727 4728 if (isa<ObjCObjectPointerType>(lhsType)) { 4729 if (rhsType->isIntegerType()) 4730 return IntToPointer; 4731 4732 // In general, C pointers are not compatible with ObjC object pointers. 4733 if (isa<PointerType>(rhsType)) { 4734 if (rhsType->isVoidPointerType()) // an exception to the rule. 4735 return Compatible; 4736 return IncompatiblePointer; 4737 } 4738 if (rhsType->isObjCObjectPointerType()) { 4739 return CheckObjCPointerTypesForAssignment(lhsType, rhsType); 4740 } 4741 if (const PointerType *RHSPT = rhsType->getAs<PointerType>()) { 4742 if (RHSPT->getPointeeType()->isVoidType()) 4743 return Compatible; 4744 } 4745 // Treat block pointers as objects. 4746 if (rhsType->isBlockPointerType()) 4747 return Compatible; 4748 return Incompatible; 4749 } 4750 if (isa<PointerType>(rhsType)) { 4751 // C99 6.5.16.1p1: the left operand is _Bool and the right is a pointer. 4752 if (lhsType == Context.BoolTy) 4753 return Compatible; 4754 4755 if (lhsType->isIntegerType()) 4756 return PointerToInt; 4757 4758 if (isa<PointerType>(lhsType)) 4759 return CheckPointerTypesForAssignment(lhsType, rhsType); 4760 4761 if (isa<BlockPointerType>(lhsType) && 4762 rhsType->getAs<PointerType>()->getPointeeType()->isVoidType()) 4763 return Compatible; 4764 return Incompatible; 4765 } 4766 if (isa<ObjCObjectPointerType>(rhsType)) { 4767 // C99 6.5.16.1p1: the left operand is _Bool and the right is a pointer. 4768 if (lhsType == Context.BoolTy) 4769 return Compatible; 4770 4771 if (lhsType->isIntegerType()) 4772 return PointerToInt; 4773 4774 // In general, C pointers are not compatible with ObjC object pointers. 4775 if (isa<PointerType>(lhsType)) { 4776 if (lhsType->isVoidPointerType()) // an exception to the rule. 4777 return Compatible; 4778 return IncompatiblePointer; 4779 } 4780 if (isa<BlockPointerType>(lhsType) && 4781 rhsType->getAs<PointerType>()->getPointeeType()->isVoidType()) 4782 return Compatible; 4783 return Incompatible; 4784 } 4785 4786 if (isa<TagType>(lhsType) && isa<TagType>(rhsType)) { 4787 if (Context.typesAreCompatible(lhsType, rhsType)) 4788 return Compatible; 4789 } 4790 return Incompatible; 4791} 4792 4793/// \brief Constructs a transparent union from an expression that is 4794/// used to initialize the transparent union. 4795static void ConstructTransparentUnion(ASTContext &C, Expr *&E, 4796 QualType UnionType, FieldDecl *Field) { 4797 // Build an initializer list that designates the appropriate member 4798 // of the transparent union. 4799 InitListExpr *Initializer = new (C) InitListExpr(C, SourceLocation(), 4800 &E, 1, 4801 SourceLocation()); 4802 Initializer->setType(UnionType); 4803 Initializer->setInitializedFieldInUnion(Field); 4804 4805 // Build a compound literal constructing a value of the transparent 4806 // union type from this initializer list. 4807 TypeSourceInfo *unionTInfo = C.getTrivialTypeSourceInfo(UnionType); 4808 E = new (C) CompoundLiteralExpr(SourceLocation(), unionTInfo, UnionType, 4809 Initializer, false); 4810} 4811 4812Sema::AssignConvertType 4813Sema::CheckTransparentUnionArgumentConstraints(QualType ArgType, Expr *&rExpr) { 4814 QualType FromType = rExpr->getType(); 4815 4816 // If the ArgType is a Union type, we want to handle a potential 4817 // transparent_union GCC extension. 4818 const RecordType *UT = ArgType->getAsUnionType(); 4819 if (!UT || !UT->getDecl()->hasAttr<TransparentUnionAttr>()) 4820 return Incompatible; 4821 4822 // The field to initialize within the transparent union. 4823 RecordDecl *UD = UT->getDecl(); 4824 FieldDecl *InitField = 0; 4825 // It's compatible if the expression matches any of the fields. 4826 for (RecordDecl::field_iterator it = UD->field_begin(), 4827 itend = UD->field_end(); 4828 it != itend; ++it) { 4829 if (it->getType()->isPointerType()) { 4830 // If the transparent union contains a pointer type, we allow: 4831 // 1) void pointer 4832 // 2) null pointer constant 4833 if (FromType->isPointerType()) 4834 if (FromType->getAs<PointerType>()->getPointeeType()->isVoidType()) { 4835 ImpCastExprToType(rExpr, it->getType(), CastExpr::CK_BitCast); 4836 InitField = *it; 4837 break; 4838 } 4839 4840 if (rExpr->isNullPointerConstant(Context, 4841 Expr::NPC_ValueDependentIsNull)) { 4842 ImpCastExprToType(rExpr, it->getType(), CastExpr::CK_IntegralToPointer); 4843 InitField = *it; 4844 break; 4845 } 4846 } 4847 4848 if (CheckAssignmentConstraints(it->getType(), rExpr->getType()) 4849 == Compatible) { 4850 InitField = *it; 4851 break; 4852 } 4853 } 4854 4855 if (!InitField) 4856 return Incompatible; 4857 4858 ConstructTransparentUnion(Context, rExpr, ArgType, InitField); 4859 return Compatible; 4860} 4861 4862Sema::AssignConvertType 4863Sema::CheckSingleAssignmentConstraints(QualType lhsType, Expr *&rExpr) { 4864 if (getLangOptions().CPlusPlus) { 4865 if (!lhsType->isRecordType()) { 4866 // C++ 5.17p3: If the left operand is not of class type, the 4867 // expression is implicitly converted (C++ 4) to the 4868 // cv-unqualified type of the left operand. 4869 if (PerformImplicitConversion(rExpr, lhsType.getUnqualifiedType(), 4870 AA_Assigning)) 4871 return Incompatible; 4872 return Compatible; 4873 } 4874 4875 // FIXME: Currently, we fall through and treat C++ classes like C 4876 // structures. 4877 } 4878 4879 // C99 6.5.16.1p1: the left operand is a pointer and the right is 4880 // a null pointer constant. 4881 if ((lhsType->isPointerType() || 4882 lhsType->isObjCObjectPointerType() || 4883 lhsType->isBlockPointerType()) 4884 && rExpr->isNullPointerConstant(Context, 4885 Expr::NPC_ValueDependentIsNull)) { 4886 ImpCastExprToType(rExpr, lhsType, CastExpr::CK_Unknown); 4887 return Compatible; 4888 } 4889 4890 // This check seems unnatural, however it is necessary to ensure the proper 4891 // conversion of functions/arrays. If the conversion were done for all 4892 // DeclExpr's (created by ActOnIdExpression), it would mess up the unary 4893 // expressions that surpress this implicit conversion (&, sizeof). 4894 // 4895 // Suppress this for references: C++ 8.5.3p5. 4896 if (!lhsType->isReferenceType()) 4897 DefaultFunctionArrayLvalueConversion(rExpr); 4898 4899 Sema::AssignConvertType result = 4900 CheckAssignmentConstraints(lhsType, rExpr->getType()); 4901 4902 // C99 6.5.16.1p2: The value of the right operand is converted to the 4903 // type of the assignment expression. 4904 // CheckAssignmentConstraints allows the left-hand side to be a reference, 4905 // so that we can use references in built-in functions even in C. 4906 // The getNonReferenceType() call makes sure that the resulting expression 4907 // does not have reference type. 4908 if (result != Incompatible && rExpr->getType() != lhsType) 4909 ImpCastExprToType(rExpr, lhsType.getNonReferenceType(), 4910 CastExpr::CK_Unknown); 4911 return result; 4912} 4913 4914QualType Sema::InvalidOperands(SourceLocation Loc, Expr *&lex, Expr *&rex) { 4915 Diag(Loc, diag::err_typecheck_invalid_operands) 4916 << lex->getType() << rex->getType() 4917 << lex->getSourceRange() << rex->getSourceRange(); 4918 return QualType(); 4919} 4920 4921QualType Sema::CheckVectorOperands(SourceLocation Loc, Expr *&lex, Expr *&rex) { 4922 // For conversion purposes, we ignore any qualifiers. 4923 // For example, "const float" and "float" are equivalent. 4924 QualType lhsType = 4925 Context.getCanonicalType(lex->getType()).getUnqualifiedType(); 4926 QualType rhsType = 4927 Context.getCanonicalType(rex->getType()).getUnqualifiedType(); 4928 4929 // If the vector types are identical, return. 4930 if (lhsType == rhsType) 4931 return lhsType; 4932 4933 // Handle the case of a vector & extvector type of the same size and element 4934 // type. It would be nice if we only had one vector type someday. 4935 if (getLangOptions().LaxVectorConversions) { 4936 // FIXME: Should we warn here? 4937 if (const VectorType *LV = lhsType->getAs<VectorType>()) { 4938 if (const VectorType *RV = rhsType->getAs<VectorType>()) 4939 if (LV->getElementType() == RV->getElementType() && 4940 LV->getNumElements() == RV->getNumElements()) { 4941 if (lhsType->isExtVectorType()) { 4942 ImpCastExprToType(rex, lhsType, CastExpr::CK_BitCast); 4943 return lhsType; 4944 } 4945 4946 ImpCastExprToType(lex, rhsType, CastExpr::CK_BitCast); 4947 return rhsType; 4948 } 4949 } 4950 } 4951 4952 // Canonicalize the ExtVector to the LHS, remember if we swapped so we can 4953 // swap back (so that we don't reverse the inputs to a subtract, for instance. 4954 bool swapped = false; 4955 if (rhsType->isExtVectorType()) { 4956 swapped = true; 4957 std::swap(rex, lex); 4958 std::swap(rhsType, lhsType); 4959 } 4960 4961 // Handle the case of an ext vector and scalar. 4962 if (const ExtVectorType *LV = lhsType->getAs<ExtVectorType>()) { 4963 QualType EltTy = LV->getElementType(); 4964 if (EltTy->isIntegralType(Context) && rhsType->isIntegralType(Context)) { 4965 if (Context.getIntegerTypeOrder(EltTy, rhsType) >= 0) { 4966 ImpCastExprToType(rex, lhsType, CastExpr::CK_IntegralCast); 4967 if (swapped) std::swap(rex, lex); 4968 return lhsType; 4969 } 4970 } 4971 if (EltTy->isRealFloatingType() && rhsType->isScalarType() && 4972 rhsType->isRealFloatingType()) { 4973 if (Context.getFloatingTypeOrder(EltTy, rhsType) >= 0) { 4974 ImpCastExprToType(rex, lhsType, CastExpr::CK_FloatingCast); 4975 if (swapped) std::swap(rex, lex); 4976 return lhsType; 4977 } 4978 } 4979 } 4980 4981 // Vectors of different size or scalar and non-ext-vector are errors. 4982 Diag(Loc, diag::err_typecheck_vector_not_convertable) 4983 << lex->getType() << rex->getType() 4984 << lex->getSourceRange() << rex->getSourceRange(); 4985 return QualType(); 4986} 4987 4988QualType Sema::CheckMultiplyDivideOperands( 4989 Expr *&lex, Expr *&rex, SourceLocation Loc, bool isCompAssign, bool isDiv) { 4990 if (lex->getType()->isVectorType() || rex->getType()->isVectorType()) 4991 return CheckVectorOperands(Loc, lex, rex); 4992 4993 QualType compType = UsualArithmeticConversions(lex, rex, isCompAssign); 4994 4995 if (!lex->getType()->isArithmeticType() || 4996 !rex->getType()->isArithmeticType()) 4997 return InvalidOperands(Loc, lex, rex); 4998 4999 // Check for division by zero. 5000 if (isDiv && 5001 rex->isNullPointerConstant(Context, Expr::NPC_ValueDependentIsNotNull)) 5002 DiagRuntimeBehavior(Loc, PDiag(diag::warn_division_by_zero) 5003 << rex->getSourceRange()); 5004 5005 return compType; 5006} 5007 5008QualType Sema::CheckRemainderOperands( 5009 Expr *&lex, Expr *&rex, SourceLocation Loc, bool isCompAssign) { 5010 if (lex->getType()->isVectorType() || rex->getType()->isVectorType()) { 5011 if (lex->getType()->isIntegerType() && rex->getType()->isIntegerType()) 5012 return CheckVectorOperands(Loc, lex, rex); 5013 return InvalidOperands(Loc, lex, rex); 5014 } 5015 5016 QualType compType = UsualArithmeticConversions(lex, rex, isCompAssign); 5017 5018 if (!lex->getType()->isIntegerType() || !rex->getType()->isIntegerType()) 5019 return InvalidOperands(Loc, lex, rex); 5020 5021 // Check for remainder by zero. 5022 if (rex->isNullPointerConstant(Context, Expr::NPC_ValueDependentIsNotNull)) 5023 DiagRuntimeBehavior(Loc, PDiag(diag::warn_remainder_by_zero) 5024 << rex->getSourceRange()); 5025 5026 return compType; 5027} 5028 5029QualType Sema::CheckAdditionOperands( // C99 6.5.6 5030 Expr *&lex, Expr *&rex, SourceLocation Loc, QualType* CompLHSTy) { 5031 if (lex->getType()->isVectorType() || rex->getType()->isVectorType()) { 5032 QualType compType = CheckVectorOperands(Loc, lex, rex); 5033 if (CompLHSTy) *CompLHSTy = compType; 5034 return compType; 5035 } 5036 5037 QualType compType = UsualArithmeticConversions(lex, rex, CompLHSTy); 5038 5039 // handle the common case first (both operands are arithmetic). 5040 if (lex->getType()->isArithmeticType() && 5041 rex->getType()->isArithmeticType()) { 5042 if (CompLHSTy) *CompLHSTy = compType; 5043 return compType; 5044 } 5045 5046 // Put any potential pointer into PExp 5047 Expr* PExp = lex, *IExp = rex; 5048 if (IExp->getType()->isAnyPointerType()) 5049 std::swap(PExp, IExp); 5050 5051 if (PExp->getType()->isAnyPointerType()) { 5052 5053 if (IExp->getType()->isIntegerType()) { 5054 QualType PointeeTy = PExp->getType()->getPointeeType(); 5055 5056 // Check for arithmetic on pointers to incomplete types. 5057 if (PointeeTy->isVoidType()) { 5058 if (getLangOptions().CPlusPlus) { 5059 Diag(Loc, diag::err_typecheck_pointer_arith_void_type) 5060 << lex->getSourceRange() << rex->getSourceRange(); 5061 return QualType(); 5062 } 5063 5064 // GNU extension: arithmetic on pointer to void 5065 Diag(Loc, diag::ext_gnu_void_ptr) 5066 << lex->getSourceRange() << rex->getSourceRange(); 5067 } else if (PointeeTy->isFunctionType()) { 5068 if (getLangOptions().CPlusPlus) { 5069 Diag(Loc, diag::err_typecheck_pointer_arith_function_type) 5070 << lex->getType() << lex->getSourceRange(); 5071 return QualType(); 5072 } 5073 5074 // GNU extension: arithmetic on pointer to function 5075 Diag(Loc, diag::ext_gnu_ptr_func_arith) 5076 << lex->getType() << lex->getSourceRange(); 5077 } else { 5078 // Check if we require a complete type. 5079 if (((PExp->getType()->isPointerType() && 5080 !PExp->getType()->isDependentType()) || 5081 PExp->getType()->isObjCObjectPointerType()) && 5082 RequireCompleteType(Loc, PointeeTy, 5083 PDiag(diag::err_typecheck_arithmetic_incomplete_type) 5084 << PExp->getSourceRange() 5085 << PExp->getType())) 5086 return QualType(); 5087 } 5088 // Diagnose bad cases where we step over interface counts. 5089 if (PointeeTy->isObjCObjectType() && LangOpts.ObjCNonFragileABI) { 5090 Diag(Loc, diag::err_arithmetic_nonfragile_interface) 5091 << PointeeTy << PExp->getSourceRange(); 5092 return QualType(); 5093 } 5094 5095 if (CompLHSTy) { 5096 QualType LHSTy = Context.isPromotableBitField(lex); 5097 if (LHSTy.isNull()) { 5098 LHSTy = lex->getType(); 5099 if (LHSTy->isPromotableIntegerType()) 5100 LHSTy = Context.getPromotedIntegerType(LHSTy); 5101 } 5102 *CompLHSTy = LHSTy; 5103 } 5104 return PExp->getType(); 5105 } 5106 } 5107 5108 return InvalidOperands(Loc, lex, rex); 5109} 5110 5111// C99 6.5.6 5112QualType Sema::CheckSubtractionOperands(Expr *&lex, Expr *&rex, 5113 SourceLocation Loc, QualType* CompLHSTy) { 5114 if (lex->getType()->isVectorType() || rex->getType()->isVectorType()) { 5115 QualType compType = CheckVectorOperands(Loc, lex, rex); 5116 if (CompLHSTy) *CompLHSTy = compType; 5117 return compType; 5118 } 5119 5120 QualType compType = UsualArithmeticConversions(lex, rex, CompLHSTy); 5121 5122 // Enforce type constraints: C99 6.5.6p3. 5123 5124 // Handle the common case first (both operands are arithmetic). 5125 if (lex->getType()->isArithmeticType() 5126 && rex->getType()->isArithmeticType()) { 5127 if (CompLHSTy) *CompLHSTy = compType; 5128 return compType; 5129 } 5130 5131 // Either ptr - int or ptr - ptr. 5132 if (lex->getType()->isAnyPointerType()) { 5133 QualType lpointee = lex->getType()->getPointeeType(); 5134 5135 // The LHS must be an completely-defined object type. 5136 5137 bool ComplainAboutVoid = false; 5138 Expr *ComplainAboutFunc = 0; 5139 if (lpointee->isVoidType()) { 5140 if (getLangOptions().CPlusPlus) { 5141 Diag(Loc, diag::err_typecheck_pointer_arith_void_type) 5142 << lex->getSourceRange() << rex->getSourceRange(); 5143 return QualType(); 5144 } 5145 5146 // GNU C extension: arithmetic on pointer to void 5147 ComplainAboutVoid = true; 5148 } else if (lpointee->isFunctionType()) { 5149 if (getLangOptions().CPlusPlus) { 5150 Diag(Loc, diag::err_typecheck_pointer_arith_function_type) 5151 << lex->getType() << lex->getSourceRange(); 5152 return QualType(); 5153 } 5154 5155 // GNU C extension: arithmetic on pointer to function 5156 ComplainAboutFunc = lex; 5157 } else if (!lpointee->isDependentType() && 5158 RequireCompleteType(Loc, lpointee, 5159 PDiag(diag::err_typecheck_sub_ptr_object) 5160 << lex->getSourceRange() 5161 << lex->getType())) 5162 return QualType(); 5163 5164 // Diagnose bad cases where we step over interface counts. 5165 if (lpointee->isObjCObjectType() && LangOpts.ObjCNonFragileABI) { 5166 Diag(Loc, diag::err_arithmetic_nonfragile_interface) 5167 << lpointee << lex->getSourceRange(); 5168 return QualType(); 5169 } 5170 5171 // The result type of a pointer-int computation is the pointer type. 5172 if (rex->getType()->isIntegerType()) { 5173 if (ComplainAboutVoid) 5174 Diag(Loc, diag::ext_gnu_void_ptr) 5175 << lex->getSourceRange() << rex->getSourceRange(); 5176 if (ComplainAboutFunc) 5177 Diag(Loc, diag::ext_gnu_ptr_func_arith) 5178 << ComplainAboutFunc->getType() 5179 << ComplainAboutFunc->getSourceRange(); 5180 5181 if (CompLHSTy) *CompLHSTy = lex->getType(); 5182 return lex->getType(); 5183 } 5184 5185 // Handle pointer-pointer subtractions. 5186 if (const PointerType *RHSPTy = rex->getType()->getAs<PointerType>()) { 5187 QualType rpointee = RHSPTy->getPointeeType(); 5188 5189 // RHS must be a completely-type object type. 5190 // Handle the GNU void* extension. 5191 if (rpointee->isVoidType()) { 5192 if (getLangOptions().CPlusPlus) { 5193 Diag(Loc, diag::err_typecheck_pointer_arith_void_type) 5194 << lex->getSourceRange() << rex->getSourceRange(); 5195 return QualType(); 5196 } 5197 5198 ComplainAboutVoid = true; 5199 } else if (rpointee->isFunctionType()) { 5200 if (getLangOptions().CPlusPlus) { 5201 Diag(Loc, diag::err_typecheck_pointer_arith_function_type) 5202 << rex->getType() << rex->getSourceRange(); 5203 return QualType(); 5204 } 5205 5206 // GNU extension: arithmetic on pointer to function 5207 if (!ComplainAboutFunc) 5208 ComplainAboutFunc = rex; 5209 } else if (!rpointee->isDependentType() && 5210 RequireCompleteType(Loc, rpointee, 5211 PDiag(diag::err_typecheck_sub_ptr_object) 5212 << rex->getSourceRange() 5213 << rex->getType())) 5214 return QualType(); 5215 5216 if (getLangOptions().CPlusPlus) { 5217 // Pointee types must be the same: C++ [expr.add] 5218 if (!Context.hasSameUnqualifiedType(lpointee, rpointee)) { 5219 Diag(Loc, diag::err_typecheck_sub_ptr_compatible) 5220 << lex->getType() << rex->getType() 5221 << lex->getSourceRange() << rex->getSourceRange(); 5222 return QualType(); 5223 } 5224 } else { 5225 // Pointee types must be compatible C99 6.5.6p3 5226 if (!Context.typesAreCompatible( 5227 Context.getCanonicalType(lpointee).getUnqualifiedType(), 5228 Context.getCanonicalType(rpointee).getUnqualifiedType())) { 5229 Diag(Loc, diag::err_typecheck_sub_ptr_compatible) 5230 << lex->getType() << rex->getType() 5231 << lex->getSourceRange() << rex->getSourceRange(); 5232 return QualType(); 5233 } 5234 } 5235 5236 if (ComplainAboutVoid) 5237 Diag(Loc, diag::ext_gnu_void_ptr) 5238 << lex->getSourceRange() << rex->getSourceRange(); 5239 if (ComplainAboutFunc) 5240 Diag(Loc, diag::ext_gnu_ptr_func_arith) 5241 << ComplainAboutFunc->getType() 5242 << ComplainAboutFunc->getSourceRange(); 5243 5244 if (CompLHSTy) *CompLHSTy = lex->getType(); 5245 return Context.getPointerDiffType(); 5246 } 5247 } 5248 5249 return InvalidOperands(Loc, lex, rex); 5250} 5251 5252// C99 6.5.7 5253QualType Sema::CheckShiftOperands(Expr *&lex, Expr *&rex, SourceLocation Loc, 5254 bool isCompAssign) { 5255 // C99 6.5.7p2: Each of the operands shall have integer type. 5256 if (!lex->getType()->isIntegerType() || !rex->getType()->isIntegerType()) 5257 return InvalidOperands(Loc, lex, rex); 5258 5259 // Vector shifts promote their scalar inputs to vector type. 5260 if (lex->getType()->isVectorType() || rex->getType()->isVectorType()) 5261 return CheckVectorOperands(Loc, lex, rex); 5262 5263 // Shifts don't perform usual arithmetic conversions, they just do integer 5264 // promotions on each operand. C99 6.5.7p3 5265 QualType LHSTy = Context.isPromotableBitField(lex); 5266 if (LHSTy.isNull()) { 5267 LHSTy = lex->getType(); 5268 if (LHSTy->isPromotableIntegerType()) 5269 LHSTy = Context.getPromotedIntegerType(LHSTy); 5270 } 5271 if (!isCompAssign) 5272 ImpCastExprToType(lex, LHSTy, CastExpr::CK_IntegralCast); 5273 5274 UsualUnaryConversions(rex); 5275 5276 // Sanity-check shift operands 5277 llvm::APSInt Right; 5278 // Check right/shifter operand 5279 if (!rex->isValueDependent() && 5280 rex->isIntegerConstantExpr(Right, Context)) { 5281 if (Right.isNegative()) 5282 Diag(Loc, diag::warn_shift_negative) << rex->getSourceRange(); 5283 else { 5284 llvm::APInt LeftBits(Right.getBitWidth(), 5285 Context.getTypeSize(lex->getType())); 5286 if (Right.uge(LeftBits)) 5287 Diag(Loc, diag::warn_shift_gt_typewidth) << rex->getSourceRange(); 5288 } 5289 } 5290 5291 // "The type of the result is that of the promoted left operand." 5292 return LHSTy; 5293} 5294 5295static bool IsWithinTemplateSpecialization(Decl *D) { 5296 if (DeclContext *DC = D->getDeclContext()) { 5297 if (isa<ClassTemplateSpecializationDecl>(DC)) 5298 return true; 5299 if (FunctionDecl *FD = dyn_cast<FunctionDecl>(DC)) 5300 return FD->isFunctionTemplateSpecialization(); 5301 } 5302 return false; 5303} 5304 5305// C99 6.5.8, C++ [expr.rel] 5306QualType Sema::CheckCompareOperands(Expr *&lex, Expr *&rex, SourceLocation Loc, 5307 unsigned OpaqueOpc, bool isRelational) { 5308 BinaryOperator::Opcode Opc = (BinaryOperator::Opcode)OpaqueOpc; 5309 5310 // Handle vector comparisons separately. 5311 if (lex->getType()->isVectorType() || rex->getType()->isVectorType()) 5312 return CheckVectorCompareOperands(lex, rex, Loc, isRelational); 5313 5314 QualType lType = lex->getType(); 5315 QualType rType = rex->getType(); 5316 5317 if (!lType->hasFloatingRepresentation() && 5318 !(lType->isBlockPointerType() && isRelational)) { 5319 // For non-floating point types, check for self-comparisons of the form 5320 // x == x, x != x, x < x, etc. These always evaluate to a constant, and 5321 // often indicate logic errors in the program. 5322 // NOTE: Don't warn about comparisons of enum constants. These can arise 5323 // from macro expansions, and are usually quite deliberate. Also don't 5324 // warn about comparisons which are only self comparisons within 5325 // a template specialization. The warnings should catch obvious cases in 5326 // the definition of the template anyways. 5327 Expr *LHSStripped = lex->IgnoreParens(); 5328 Expr *RHSStripped = rex->IgnoreParens(); 5329 if (DeclRefExpr* DRL = dyn_cast<DeclRefExpr>(LHSStripped)) { 5330 if (DeclRefExpr* DRR = dyn_cast<DeclRefExpr>(RHSStripped)) { 5331 if (DRL->getDecl() == DRR->getDecl() && 5332 !isa<EnumConstantDecl>(DRL->getDecl()) && 5333 !IsWithinTemplateSpecialization(DRL->getDecl())) { 5334 DiagRuntimeBehavior(Loc, PDiag(diag::warn_comparison_always) 5335 << 0 // self- 5336 << (Opc == BinaryOperator::EQ 5337 || Opc == BinaryOperator::LE 5338 || Opc == BinaryOperator::GE)); 5339 } else if (lType->isArrayType() && rType->isArrayType() && 5340 !DRL->getDecl()->getType()->isReferenceType() && 5341 !DRR->getDecl()->getType()->isReferenceType()) { 5342 // what is it always going to eval to? 5343 char always_evals_to; 5344 switch(Opc) { 5345 case BinaryOperator::EQ: // e.g. array1 == array2 5346 always_evals_to = 0; // false 5347 break; 5348 case BinaryOperator::NE: // e.g. array1 != array2 5349 always_evals_to = 1; // true 5350 break; 5351 default: 5352 // best we can say is 'a constant' 5353 always_evals_to = 2; // e.g. array1 <= array2 5354 break; 5355 } 5356 DiagRuntimeBehavior(Loc, PDiag(diag::warn_comparison_always) 5357 << 1 // array 5358 << always_evals_to); 5359 } 5360 } 5361 } 5362 5363 if (isa<CastExpr>(LHSStripped)) 5364 LHSStripped = LHSStripped->IgnoreParenCasts(); 5365 if (isa<CastExpr>(RHSStripped)) 5366 RHSStripped = RHSStripped->IgnoreParenCasts(); 5367 5368 // Warn about comparisons against a string constant (unless the other 5369 // operand is null), the user probably wants strcmp. 5370 Expr *literalString = 0; 5371 Expr *literalStringStripped = 0; 5372 if ((isa<StringLiteral>(LHSStripped) || isa<ObjCEncodeExpr>(LHSStripped)) && 5373 !RHSStripped->isNullPointerConstant(Context, 5374 Expr::NPC_ValueDependentIsNull)) { 5375 literalString = lex; 5376 literalStringStripped = LHSStripped; 5377 } else if ((isa<StringLiteral>(RHSStripped) || 5378 isa<ObjCEncodeExpr>(RHSStripped)) && 5379 !LHSStripped->isNullPointerConstant(Context, 5380 Expr::NPC_ValueDependentIsNull)) { 5381 literalString = rex; 5382 literalStringStripped = RHSStripped; 5383 } 5384 5385 if (literalString) { 5386 std::string resultComparison; 5387 switch (Opc) { 5388 case BinaryOperator::LT: resultComparison = ") < 0"; break; 5389 case BinaryOperator::GT: resultComparison = ") > 0"; break; 5390 case BinaryOperator::LE: resultComparison = ") <= 0"; break; 5391 case BinaryOperator::GE: resultComparison = ") >= 0"; break; 5392 case BinaryOperator::EQ: resultComparison = ") == 0"; break; 5393 case BinaryOperator::NE: resultComparison = ") != 0"; break; 5394 default: assert(false && "Invalid comparison operator"); 5395 } 5396 5397 DiagRuntimeBehavior(Loc, 5398 PDiag(diag::warn_stringcompare) 5399 << isa<ObjCEncodeExpr>(literalStringStripped) 5400 << literalString->getSourceRange()); 5401 } 5402 } 5403 5404 // C99 6.5.8p3 / C99 6.5.9p4 5405 if (lex->getType()->isArithmeticType() && rex->getType()->isArithmeticType()) 5406 UsualArithmeticConversions(lex, rex); 5407 else { 5408 UsualUnaryConversions(lex); 5409 UsualUnaryConversions(rex); 5410 } 5411 5412 lType = lex->getType(); 5413 rType = rex->getType(); 5414 5415 // The result of comparisons is 'bool' in C++, 'int' in C. 5416 QualType ResultTy = getLangOptions().CPlusPlus ? Context.BoolTy:Context.IntTy; 5417 5418 if (isRelational) { 5419 if (lType->isRealType() && rType->isRealType()) 5420 return ResultTy; 5421 } else { 5422 // Check for comparisons of floating point operands using != and ==. 5423 if (lType->hasFloatingRepresentation()) 5424 CheckFloatComparison(Loc,lex,rex); 5425 5426 if (lType->isArithmeticType() && rType->isArithmeticType()) 5427 return ResultTy; 5428 } 5429 5430 bool LHSIsNull = lex->isNullPointerConstant(Context, 5431 Expr::NPC_ValueDependentIsNull); 5432 bool RHSIsNull = rex->isNullPointerConstant(Context, 5433 Expr::NPC_ValueDependentIsNull); 5434 5435 // All of the following pointer-related warnings are GCC extensions, except 5436 // when handling null pointer constants. 5437 if (lType->isPointerType() && rType->isPointerType()) { // C99 6.5.8p2 5438 QualType LCanPointeeTy = 5439 Context.getCanonicalType(lType->getAs<PointerType>()->getPointeeType()); 5440 QualType RCanPointeeTy = 5441 Context.getCanonicalType(rType->getAs<PointerType>()->getPointeeType()); 5442 5443 if (getLangOptions().CPlusPlus) { 5444 if (LCanPointeeTy == RCanPointeeTy) 5445 return ResultTy; 5446 if (!isRelational && 5447 (LCanPointeeTy->isVoidType() || RCanPointeeTy->isVoidType())) { 5448 // Valid unless comparison between non-null pointer and function pointer 5449 // This is a gcc extension compatibility comparison. 5450 // In a SFINAE context, we treat this as a hard error to maintain 5451 // conformance with the C++ standard. 5452 if ((LCanPointeeTy->isFunctionType() || RCanPointeeTy->isFunctionType()) 5453 && !LHSIsNull && !RHSIsNull) { 5454 Diag(Loc, 5455 isSFINAEContext()? 5456 diag::err_typecheck_comparison_of_fptr_to_void 5457 : diag::ext_typecheck_comparison_of_fptr_to_void) 5458 << lType << rType << lex->getSourceRange() << rex->getSourceRange(); 5459 5460 if (isSFINAEContext()) 5461 return QualType(); 5462 5463 ImpCastExprToType(rex, lType, CastExpr::CK_BitCast); 5464 return ResultTy; 5465 } 5466 } 5467 // C++ [expr.rel]p2: 5468 // [...] Pointer conversions (4.10) and qualification 5469 // conversions (4.4) are performed on pointer operands (or on 5470 // a pointer operand and a null pointer constant) to bring 5471 // them to their composite pointer type. [...] 5472 // 5473 // C++ [expr.eq]p1 uses the same notion for (in)equality 5474 // comparisons of pointers. 5475 bool NonStandardCompositeType = false; 5476 QualType T = FindCompositePointerType(Loc, lex, rex, 5477 isSFINAEContext()? 0 : &NonStandardCompositeType); 5478 if (T.isNull()) { 5479 Diag(Loc, diag::err_typecheck_comparison_of_distinct_pointers) 5480 << lType << rType << lex->getSourceRange() << rex->getSourceRange(); 5481 return QualType(); 5482 } else if (NonStandardCompositeType) { 5483 Diag(Loc, 5484 diag::ext_typecheck_comparison_of_distinct_pointers_nonstandard) 5485 << lType << rType << T 5486 << lex->getSourceRange() << rex->getSourceRange(); 5487 } 5488 5489 ImpCastExprToType(lex, T, CastExpr::CK_BitCast); 5490 ImpCastExprToType(rex, T, CastExpr::CK_BitCast); 5491 return ResultTy; 5492 } 5493 // C99 6.5.9p2 and C99 6.5.8p2 5494 if (Context.typesAreCompatible(LCanPointeeTy.getUnqualifiedType(), 5495 RCanPointeeTy.getUnqualifiedType())) { 5496 // Valid unless a relational comparison of function pointers 5497 if (isRelational && LCanPointeeTy->isFunctionType()) { 5498 Diag(Loc, diag::ext_typecheck_ordered_comparison_of_function_pointers) 5499 << lType << rType << lex->getSourceRange() << rex->getSourceRange(); 5500 } 5501 } else if (!isRelational && 5502 (LCanPointeeTy->isVoidType() || RCanPointeeTy->isVoidType())) { 5503 // Valid unless comparison between non-null pointer and function pointer 5504 if ((LCanPointeeTy->isFunctionType() || RCanPointeeTy->isFunctionType()) 5505 && !LHSIsNull && !RHSIsNull) { 5506 Diag(Loc, diag::ext_typecheck_comparison_of_fptr_to_void) 5507 << lType << rType << lex->getSourceRange() << rex->getSourceRange(); 5508 } 5509 } else { 5510 // Invalid 5511 Diag(Loc, diag::ext_typecheck_comparison_of_distinct_pointers) 5512 << lType << rType << lex->getSourceRange() << rex->getSourceRange(); 5513 } 5514 if (LCanPointeeTy != RCanPointeeTy) 5515 ImpCastExprToType(rex, lType, CastExpr::CK_BitCast); 5516 return ResultTy; 5517 } 5518 5519 if (getLangOptions().CPlusPlus) { 5520 // Comparison of pointers with null pointer constants and equality 5521 // comparisons of member pointers to null pointer constants. 5522 if (RHSIsNull && 5523 (lType->isPointerType() || 5524 (!isRelational && lType->isMemberPointerType()))) { 5525 ImpCastExprToType(rex, lType, CastExpr::CK_NullToMemberPointer); 5526 return ResultTy; 5527 } 5528 if (LHSIsNull && 5529 (rType->isPointerType() || 5530 (!isRelational && rType->isMemberPointerType()))) { 5531 ImpCastExprToType(lex, rType, CastExpr::CK_NullToMemberPointer); 5532 return ResultTy; 5533 } 5534 5535 // Comparison of member pointers. 5536 if (!isRelational && 5537 lType->isMemberPointerType() && rType->isMemberPointerType()) { 5538 // C++ [expr.eq]p2: 5539 // In addition, pointers to members can be compared, or a pointer to 5540 // member and a null pointer constant. Pointer to member conversions 5541 // (4.11) and qualification conversions (4.4) are performed to bring 5542 // them to a common type. If one operand is a null pointer constant, 5543 // the common type is the type of the other operand. Otherwise, the 5544 // common type is a pointer to member type similar (4.4) to the type 5545 // of one of the operands, with a cv-qualification signature (4.4) 5546 // that is the union of the cv-qualification signatures of the operand 5547 // types. 5548 bool NonStandardCompositeType = false; 5549 QualType T = FindCompositePointerType(Loc, lex, rex, 5550 isSFINAEContext()? 0 : &NonStandardCompositeType); 5551 if (T.isNull()) { 5552 Diag(Loc, diag::err_typecheck_comparison_of_distinct_pointers) 5553 << lType << rType << lex->getSourceRange() << rex->getSourceRange(); 5554 return QualType(); 5555 } else if (NonStandardCompositeType) { 5556 Diag(Loc, 5557 diag::ext_typecheck_comparison_of_distinct_pointers_nonstandard) 5558 << lType << rType << T 5559 << lex->getSourceRange() << rex->getSourceRange(); 5560 } 5561 5562 ImpCastExprToType(lex, T, CastExpr::CK_BitCast); 5563 ImpCastExprToType(rex, T, CastExpr::CK_BitCast); 5564 return ResultTy; 5565 } 5566 5567 // Comparison of nullptr_t with itself. 5568 if (lType->isNullPtrType() && rType->isNullPtrType()) 5569 return ResultTy; 5570 } 5571 5572 // Handle block pointer types. 5573 if (!isRelational && lType->isBlockPointerType() && rType->isBlockPointerType()) { 5574 QualType lpointee = lType->getAs<BlockPointerType>()->getPointeeType(); 5575 QualType rpointee = rType->getAs<BlockPointerType>()->getPointeeType(); 5576 5577 if (!LHSIsNull && !RHSIsNull && 5578 !Context.typesAreCompatible(lpointee, rpointee)) { 5579 Diag(Loc, diag::err_typecheck_comparison_of_distinct_blocks) 5580 << lType << rType << lex->getSourceRange() << rex->getSourceRange(); 5581 } 5582 ImpCastExprToType(rex, lType, CastExpr::CK_BitCast); 5583 return ResultTy; 5584 } 5585 // Allow block pointers to be compared with null pointer constants. 5586 if (!isRelational 5587 && ((lType->isBlockPointerType() && rType->isPointerType()) 5588 || (lType->isPointerType() && rType->isBlockPointerType()))) { 5589 if (!LHSIsNull && !RHSIsNull) { 5590 if (!((rType->isPointerType() && rType->getAs<PointerType>() 5591 ->getPointeeType()->isVoidType()) 5592 || (lType->isPointerType() && lType->getAs<PointerType>() 5593 ->getPointeeType()->isVoidType()))) 5594 Diag(Loc, diag::err_typecheck_comparison_of_distinct_blocks) 5595 << lType << rType << lex->getSourceRange() << rex->getSourceRange(); 5596 } 5597 ImpCastExprToType(rex, lType, CastExpr::CK_BitCast); 5598 return ResultTy; 5599 } 5600 5601 if ((lType->isObjCObjectPointerType() || rType->isObjCObjectPointerType())) { 5602 if (lType->isPointerType() || rType->isPointerType()) { 5603 const PointerType *LPT = lType->getAs<PointerType>(); 5604 const PointerType *RPT = rType->getAs<PointerType>(); 5605 bool LPtrToVoid = LPT ? 5606 Context.getCanonicalType(LPT->getPointeeType())->isVoidType() : false; 5607 bool RPtrToVoid = RPT ? 5608 Context.getCanonicalType(RPT->getPointeeType())->isVoidType() : false; 5609 5610 if (!LPtrToVoid && !RPtrToVoid && 5611 !Context.typesAreCompatible(lType, rType)) { 5612 Diag(Loc, diag::ext_typecheck_comparison_of_distinct_pointers) 5613 << lType << rType << lex->getSourceRange() << rex->getSourceRange(); 5614 } 5615 ImpCastExprToType(rex, lType, CastExpr::CK_BitCast); 5616 return ResultTy; 5617 } 5618 if (lType->isObjCObjectPointerType() && rType->isObjCObjectPointerType()) { 5619 if (!Context.areComparableObjCPointerTypes(lType, rType)) 5620 Diag(Loc, diag::ext_typecheck_comparison_of_distinct_pointers) 5621 << lType << rType << lex->getSourceRange() << rex->getSourceRange(); 5622 ImpCastExprToType(rex, lType, CastExpr::CK_BitCast); 5623 return ResultTy; 5624 } 5625 } 5626 if ((lType->isAnyPointerType() && rType->isIntegerType()) || 5627 (lType->isIntegerType() && rType->isAnyPointerType())) { 5628 unsigned DiagID = 0; 5629 bool isError = false; 5630 if ((LHSIsNull && lType->isIntegerType()) || 5631 (RHSIsNull && rType->isIntegerType())) { 5632 if (isRelational && !getLangOptions().CPlusPlus) 5633 DiagID = diag::ext_typecheck_ordered_comparison_of_pointer_and_zero; 5634 } else if (isRelational && !getLangOptions().CPlusPlus) 5635 DiagID = diag::ext_typecheck_ordered_comparison_of_pointer_integer; 5636 else if (getLangOptions().CPlusPlus) { 5637 DiagID = diag::err_typecheck_comparison_of_pointer_integer; 5638 isError = true; 5639 } else 5640 DiagID = diag::ext_typecheck_comparison_of_pointer_integer; 5641 5642 if (DiagID) { 5643 Diag(Loc, DiagID) 5644 << lType << rType << lex->getSourceRange() << rex->getSourceRange(); 5645 if (isError) 5646 return QualType(); 5647 } 5648 5649 if (lType->isIntegerType()) 5650 ImpCastExprToType(lex, rType, CastExpr::CK_IntegralToPointer); 5651 else 5652 ImpCastExprToType(rex, lType, CastExpr::CK_IntegralToPointer); 5653 return ResultTy; 5654 } 5655 5656 // Handle block pointers. 5657 if (!isRelational && RHSIsNull 5658 && lType->isBlockPointerType() && rType->isIntegerType()) { 5659 ImpCastExprToType(rex, lType, CastExpr::CK_IntegralToPointer); 5660 return ResultTy; 5661 } 5662 if (!isRelational && LHSIsNull 5663 && lType->isIntegerType() && rType->isBlockPointerType()) { 5664 ImpCastExprToType(lex, rType, CastExpr::CK_IntegralToPointer); 5665 return ResultTy; 5666 } 5667 return InvalidOperands(Loc, lex, rex); 5668} 5669 5670/// CheckVectorCompareOperands - vector comparisons are a clang extension that 5671/// operates on extended vector types. Instead of producing an IntTy result, 5672/// like a scalar comparison, a vector comparison produces a vector of integer 5673/// types. 5674QualType Sema::CheckVectorCompareOperands(Expr *&lex, Expr *&rex, 5675 SourceLocation Loc, 5676 bool isRelational) { 5677 // Check to make sure we're operating on vectors of the same type and width, 5678 // Allowing one side to be a scalar of element type. 5679 QualType vType = CheckVectorOperands(Loc, lex, rex); 5680 if (vType.isNull()) 5681 return vType; 5682 5683 QualType lType = lex->getType(); 5684 QualType rType = rex->getType(); 5685 5686 // For non-floating point types, check for self-comparisons of the form 5687 // x == x, x != x, x < x, etc. These always evaluate to a constant, and 5688 // often indicate logic errors in the program. 5689 if (!lType->hasFloatingRepresentation()) { 5690 if (DeclRefExpr* DRL = dyn_cast<DeclRefExpr>(lex->IgnoreParens())) 5691 if (DeclRefExpr* DRR = dyn_cast<DeclRefExpr>(rex->IgnoreParens())) 5692 if (DRL->getDecl() == DRR->getDecl()) 5693 DiagRuntimeBehavior(Loc, 5694 PDiag(diag::warn_comparison_always) 5695 << 0 // self- 5696 << 2 // "a constant" 5697 ); 5698 } 5699 5700 // Check for comparisons of floating point operands using != and ==. 5701 if (!isRelational && lType->hasFloatingRepresentation()) { 5702 assert (rType->hasFloatingRepresentation()); 5703 CheckFloatComparison(Loc,lex,rex); 5704 } 5705 5706 // Return the type for the comparison, which is the same as vector type for 5707 // integer vectors, or an integer type of identical size and number of 5708 // elements for floating point vectors. 5709 if (lType->isIntegerType()) 5710 return lType; 5711 5712 const VectorType *VTy = lType->getAs<VectorType>(); 5713 unsigned TypeSize = Context.getTypeSize(VTy->getElementType()); 5714 if (TypeSize == Context.getTypeSize(Context.IntTy)) 5715 return Context.getExtVectorType(Context.IntTy, VTy->getNumElements()); 5716 if (TypeSize == Context.getTypeSize(Context.LongTy)) 5717 return Context.getExtVectorType(Context.LongTy, VTy->getNumElements()); 5718 5719 assert(TypeSize == Context.getTypeSize(Context.LongLongTy) && 5720 "Unhandled vector element size in vector compare"); 5721 return Context.getExtVectorType(Context.LongLongTy, VTy->getNumElements()); 5722} 5723 5724inline QualType Sema::CheckBitwiseOperands( 5725 Expr *&lex, Expr *&rex, SourceLocation Loc, bool isCompAssign) { 5726 if (lex->getType()->isVectorType() || rex->getType()->isVectorType()) 5727 return CheckVectorOperands(Loc, lex, rex); 5728 5729 QualType compType = UsualArithmeticConversions(lex, rex, isCompAssign); 5730 5731 if (lex->getType()->isIntegerType() && rex->getType()->isIntegerType()) 5732 return compType; 5733 return InvalidOperands(Loc, lex, rex); 5734} 5735 5736inline QualType Sema::CheckLogicalOperands( // C99 6.5.[13,14] 5737 Expr *&lex, Expr *&rex, SourceLocation Loc) { 5738 if (!Context.getLangOptions().CPlusPlus) { 5739 UsualUnaryConversions(lex); 5740 UsualUnaryConversions(rex); 5741 5742 if (!lex->getType()->isScalarType() || !rex->getType()->isScalarType()) 5743 return InvalidOperands(Loc, lex, rex); 5744 5745 return Context.IntTy; 5746 } 5747 5748 // The following is safe because we only use this method for 5749 // non-overloadable operands. 5750 5751 // C++ [expr.log.and]p1 5752 // C++ [expr.log.or]p1 5753 // The operands are both contextually converted to type bool. 5754 if (PerformContextuallyConvertToBool(lex) || 5755 PerformContextuallyConvertToBool(rex)) 5756 return InvalidOperands(Loc, lex, rex); 5757 5758 // C++ [expr.log.and]p2 5759 // C++ [expr.log.or]p2 5760 // The result is a bool. 5761 return Context.BoolTy; 5762} 5763 5764/// IsReadonlyProperty - Verify that otherwise a valid l-value expression 5765/// is a read-only property; return true if so. A readonly property expression 5766/// depends on various declarations and thus must be treated specially. 5767/// 5768static bool IsReadonlyProperty(Expr *E, Sema &S) { 5769 if (E->getStmtClass() == Expr::ObjCPropertyRefExprClass) { 5770 const ObjCPropertyRefExpr* PropExpr = cast<ObjCPropertyRefExpr>(E); 5771 if (ObjCPropertyDecl *PDecl = PropExpr->getProperty()) { 5772 QualType BaseType = PropExpr->getBase()->getType(); 5773 if (const ObjCObjectPointerType *OPT = 5774 BaseType->getAsObjCInterfacePointerType()) 5775 if (ObjCInterfaceDecl *IFace = OPT->getInterfaceDecl()) 5776 if (S.isPropertyReadonly(PDecl, IFace)) 5777 return true; 5778 } 5779 } 5780 return false; 5781} 5782 5783/// CheckForModifiableLvalue - Verify that E is a modifiable lvalue. If not, 5784/// emit an error and return true. If so, return false. 5785static bool CheckForModifiableLvalue(Expr *E, SourceLocation Loc, Sema &S) { 5786 SourceLocation OrigLoc = Loc; 5787 Expr::isModifiableLvalueResult IsLV = E->isModifiableLvalue(S.Context, 5788 &Loc); 5789 if (IsLV == Expr::MLV_Valid && IsReadonlyProperty(E, S)) 5790 IsLV = Expr::MLV_ReadonlyProperty; 5791 if (IsLV == Expr::MLV_Valid) 5792 return false; 5793 5794 unsigned Diag = 0; 5795 bool NeedType = false; 5796 switch (IsLV) { // C99 6.5.16p2 5797 case Expr::MLV_ConstQualified: Diag = diag::err_typecheck_assign_const; break; 5798 case Expr::MLV_ArrayType: 5799 Diag = diag::err_typecheck_array_not_modifiable_lvalue; 5800 NeedType = true; 5801 break; 5802 case Expr::MLV_NotObjectType: 5803 Diag = diag::err_typecheck_non_object_not_modifiable_lvalue; 5804 NeedType = true; 5805 break; 5806 case Expr::MLV_LValueCast: 5807 Diag = diag::err_typecheck_lvalue_casts_not_supported; 5808 break; 5809 case Expr::MLV_Valid: 5810 llvm_unreachable("did not take early return for MLV_Valid"); 5811 case Expr::MLV_InvalidExpression: 5812 case Expr::MLV_MemberFunction: 5813 case Expr::MLV_ClassTemporary: 5814 Diag = diag::err_typecheck_expression_not_modifiable_lvalue; 5815 break; 5816 case Expr::MLV_IncompleteType: 5817 case Expr::MLV_IncompleteVoidType: 5818 return S.RequireCompleteType(Loc, E->getType(), 5819 S.PDiag(diag::err_typecheck_incomplete_type_not_modifiable_lvalue) 5820 << E->getSourceRange()); 5821 case Expr::MLV_DuplicateVectorComponents: 5822 Diag = diag::err_typecheck_duplicate_vector_components_not_mlvalue; 5823 break; 5824 case Expr::MLV_NotBlockQualified: 5825 Diag = diag::err_block_decl_ref_not_modifiable_lvalue; 5826 break; 5827 case Expr::MLV_ReadonlyProperty: 5828 Diag = diag::error_readonly_property_assignment; 5829 break; 5830 case Expr::MLV_NoSetterProperty: 5831 Diag = diag::error_nosetter_property_assignment; 5832 break; 5833 case Expr::MLV_SubObjCPropertySetting: 5834 Diag = diag::error_no_subobject_property_setting; 5835 break; 5836 } 5837 5838 SourceRange Assign; 5839 if (Loc != OrigLoc) 5840 Assign = SourceRange(OrigLoc, OrigLoc); 5841 if (NeedType) 5842 S.Diag(Loc, Diag) << E->getType() << E->getSourceRange() << Assign; 5843 else 5844 S.Diag(Loc, Diag) << E->getSourceRange() << Assign; 5845 return true; 5846} 5847 5848 5849 5850// C99 6.5.16.1 5851QualType Sema::CheckAssignmentOperands(Expr *LHS, Expr *&RHS, 5852 SourceLocation Loc, 5853 QualType CompoundType) { 5854 // Verify that LHS is a modifiable lvalue, and emit error if not. 5855 if (CheckForModifiableLvalue(LHS, Loc, *this)) 5856 return QualType(); 5857 5858 QualType LHSType = LHS->getType(); 5859 QualType RHSType = CompoundType.isNull() ? RHS->getType() : CompoundType; 5860 AssignConvertType ConvTy; 5861 if (CompoundType.isNull()) { 5862 QualType LHSTy(LHSType); 5863 // Simple assignment "x = y". 5864 if (const ObjCImplicitSetterGetterRefExpr *OISGE = 5865 dyn_cast<ObjCImplicitSetterGetterRefExpr>(LHS)) { 5866 // If using property-dot syntax notation for assignment, and there is a 5867 // setter, RHS expression is being passed to the setter argument. So, 5868 // type conversion (and comparison) is RHS to setter's argument type. 5869 if (const ObjCMethodDecl *SetterMD = OISGE->getSetterMethod()) { 5870 ObjCMethodDecl::param_iterator P = SetterMD->param_begin(); 5871 LHSTy = (*P)->getType(); 5872 } 5873 } 5874 5875 ConvTy = CheckSingleAssignmentConstraints(LHSTy, RHS); 5876 // Special case of NSObject attributes on c-style pointer types. 5877 if (ConvTy == IncompatiblePointer && 5878 ((Context.isObjCNSObjectType(LHSType) && 5879 RHSType->isObjCObjectPointerType()) || 5880 (Context.isObjCNSObjectType(RHSType) && 5881 LHSType->isObjCObjectPointerType()))) 5882 ConvTy = Compatible; 5883 5884 // If the RHS is a unary plus or minus, check to see if they = and + are 5885 // right next to each other. If so, the user may have typo'd "x =+ 4" 5886 // instead of "x += 4". 5887 Expr *RHSCheck = RHS; 5888 if (ImplicitCastExpr *ICE = dyn_cast<ImplicitCastExpr>(RHSCheck)) 5889 RHSCheck = ICE->getSubExpr(); 5890 if (UnaryOperator *UO = dyn_cast<UnaryOperator>(RHSCheck)) { 5891 if ((UO->getOpcode() == UnaryOperator::Plus || 5892 UO->getOpcode() == UnaryOperator::Minus) && 5893 Loc.isFileID() && UO->getOperatorLoc().isFileID() && 5894 // Only if the two operators are exactly adjacent. 5895 Loc.getFileLocWithOffset(1) == UO->getOperatorLoc() && 5896 // And there is a space or other character before the subexpr of the 5897 // unary +/-. We don't want to warn on "x=-1". 5898 Loc.getFileLocWithOffset(2) != UO->getSubExpr()->getLocStart() && 5899 UO->getSubExpr()->getLocStart().isFileID()) { 5900 Diag(Loc, diag::warn_not_compound_assign) 5901 << (UO->getOpcode() == UnaryOperator::Plus ? "+" : "-") 5902 << SourceRange(UO->getOperatorLoc(), UO->getOperatorLoc()); 5903 } 5904 } 5905 } else { 5906 // Compound assignment "x += y" 5907 ConvTy = CheckAssignmentConstraints(LHSType, RHSType); 5908 } 5909 5910 if (DiagnoseAssignmentResult(ConvTy, Loc, LHSType, RHSType, 5911 RHS, AA_Assigning)) 5912 return QualType(); 5913 5914 5915 // Check to see if the destination operand is a dereferenced null pointer. If 5916 // so, and if not volatile-qualified, this is undefined behavior that the 5917 // optimizer will delete, so warn about it. People sometimes try to use this 5918 // to get a deterministic trap and are surprised by clang's behavior. This 5919 // only handles the pattern "*null = whatever", which is a very syntactic 5920 // check. 5921 if (UnaryOperator *UO = dyn_cast<UnaryOperator>(LHS->IgnoreParenCasts())) 5922 if (UO->getOpcode() == UnaryOperator::Deref && 5923 UO->getSubExpr()->IgnoreParenCasts()-> 5924 isNullPointerConstant(Context, Expr::NPC_ValueDependentIsNotNull) && 5925 !UO->getType().isVolatileQualified()) { 5926 Diag(UO->getOperatorLoc(), diag::warn_indirection_through_null) 5927 << UO->getSubExpr()->getSourceRange(); 5928 Diag(UO->getOperatorLoc(), diag::note_indirection_through_null); 5929 } 5930 5931 // C99 6.5.16p3: The type of an assignment expression is the type of the 5932 // left operand unless the left operand has qualified type, in which case 5933 // it is the unqualified version of the type of the left operand. 5934 // C99 6.5.16.1p2: In simple assignment, the value of the right operand 5935 // is converted to the type of the assignment expression (above). 5936 // C++ 5.17p1: the type of the assignment expression is that of its left 5937 // operand. 5938 return LHSType.getUnqualifiedType(); 5939} 5940 5941// C99 6.5.17 5942QualType Sema::CheckCommaOperands(Expr *LHS, Expr *&RHS, SourceLocation Loc) { 5943 DiagnoseUnusedExprResult(LHS); 5944 5945 // Comma performs lvalue conversion (C99 6.3.2.1), but not unary conversions. 5946 // C++ does not perform this conversion (C++ [expr.comma]p1). 5947 if (!getLangOptions().CPlusPlus) 5948 DefaultFunctionArrayLvalueConversion(RHS); 5949 5950 // FIXME: Check that RHS type is complete in C mode (it's legal for it to be 5951 // incomplete in C++). 5952 5953 return RHS->getType(); 5954} 5955 5956/// CheckIncrementDecrementOperand - unlike most "Check" methods, this routine 5957/// doesn't need to call UsualUnaryConversions or UsualArithmeticConversions. 5958QualType Sema::CheckIncrementDecrementOperand(Expr *Op, SourceLocation OpLoc, 5959 bool isInc, bool isPrefix) { 5960 if (Op->isTypeDependent()) 5961 return Context.DependentTy; 5962 5963 QualType ResType = Op->getType(); 5964 assert(!ResType.isNull() && "no type for increment/decrement expression"); 5965 5966 if (getLangOptions().CPlusPlus && ResType->isBooleanType()) { 5967 // Decrement of bool is not allowed. 5968 if (!isInc) { 5969 Diag(OpLoc, diag::err_decrement_bool) << Op->getSourceRange(); 5970 return QualType(); 5971 } 5972 // Increment of bool sets it to true, but is deprecated. 5973 Diag(OpLoc, diag::warn_increment_bool) << Op->getSourceRange(); 5974 } else if (ResType->isRealType()) { 5975 // OK! 5976 } else if (ResType->isAnyPointerType()) { 5977 QualType PointeeTy = ResType->getPointeeType(); 5978 5979 // C99 6.5.2.4p2, 6.5.6p2 5980 if (PointeeTy->isVoidType()) { 5981 if (getLangOptions().CPlusPlus) { 5982 Diag(OpLoc, diag::err_typecheck_pointer_arith_void_type) 5983 << Op->getSourceRange(); 5984 return QualType(); 5985 } 5986 5987 // Pointer to void is a GNU extension in C. 5988 Diag(OpLoc, diag::ext_gnu_void_ptr) << Op->getSourceRange(); 5989 } else if (PointeeTy->isFunctionType()) { 5990 if (getLangOptions().CPlusPlus) { 5991 Diag(OpLoc, diag::err_typecheck_pointer_arith_function_type) 5992 << Op->getType() << Op->getSourceRange(); 5993 return QualType(); 5994 } 5995 5996 Diag(OpLoc, diag::ext_gnu_ptr_func_arith) 5997 << ResType << Op->getSourceRange(); 5998 } else if (RequireCompleteType(OpLoc, PointeeTy, 5999 PDiag(diag::err_typecheck_arithmetic_incomplete_type) 6000 << Op->getSourceRange() 6001 << ResType)) 6002 return QualType(); 6003 // Diagnose bad cases where we step over interface counts. 6004 else if (PointeeTy->isObjCObjectType() && LangOpts.ObjCNonFragileABI) { 6005 Diag(OpLoc, diag::err_arithmetic_nonfragile_interface) 6006 << PointeeTy << Op->getSourceRange(); 6007 return QualType(); 6008 } 6009 } else if (ResType->isAnyComplexType()) { 6010 // C99 does not support ++/-- on complex types, we allow as an extension. 6011 Diag(OpLoc, diag::ext_integer_increment_complex) 6012 << ResType << Op->getSourceRange(); 6013 } else { 6014 Diag(OpLoc, diag::err_typecheck_illegal_increment_decrement) 6015 << ResType << int(isInc) << Op->getSourceRange(); 6016 return QualType(); 6017 } 6018 // At this point, we know we have a real, complex or pointer type. 6019 // Now make sure the operand is a modifiable lvalue. 6020 if (CheckForModifiableLvalue(Op, OpLoc, *this)) 6021 return QualType(); 6022 // In C++, a prefix increment is the same type as the operand. Otherwise 6023 // (in C or with postfix), the increment is the unqualified type of the 6024 // operand. 6025 return isPrefix && getLangOptions().CPlusPlus 6026 ? ResType : ResType.getUnqualifiedType(); 6027} 6028 6029/// getPrimaryDecl - Helper function for CheckAddressOfOperand(). 6030/// This routine allows us to typecheck complex/recursive expressions 6031/// where the declaration is needed for type checking. We only need to 6032/// handle cases when the expression references a function designator 6033/// or is an lvalue. Here are some examples: 6034/// - &(x) => x 6035/// - &*****f => f for f a function designator. 6036/// - &s.xx => s 6037/// - &s.zz[1].yy -> s, if zz is an array 6038/// - *(x + 1) -> x, if x is an array 6039/// - &"123"[2] -> 0 6040/// - & __real__ x -> x 6041static NamedDecl *getPrimaryDecl(Expr *E) { 6042 switch (E->getStmtClass()) { 6043 case Stmt::DeclRefExprClass: 6044 return cast<DeclRefExpr>(E)->getDecl(); 6045 case Stmt::MemberExprClass: 6046 // If this is an arrow operator, the address is an offset from 6047 // the base's value, so the object the base refers to is 6048 // irrelevant. 6049 if (cast<MemberExpr>(E)->isArrow()) 6050 return 0; 6051 // Otherwise, the expression refers to a part of the base 6052 return getPrimaryDecl(cast<MemberExpr>(E)->getBase()); 6053 case Stmt::ArraySubscriptExprClass: { 6054 // FIXME: This code shouldn't be necessary! We should catch the implicit 6055 // promotion of register arrays earlier. 6056 Expr* Base = cast<ArraySubscriptExpr>(E)->getBase(); 6057 if (ImplicitCastExpr* ICE = dyn_cast<ImplicitCastExpr>(Base)) { 6058 if (ICE->getSubExpr()->getType()->isArrayType()) 6059 return getPrimaryDecl(ICE->getSubExpr()); 6060 } 6061 return 0; 6062 } 6063 case Stmt::UnaryOperatorClass: { 6064 UnaryOperator *UO = cast<UnaryOperator>(E); 6065 6066 switch(UO->getOpcode()) { 6067 case UnaryOperator::Real: 6068 case UnaryOperator::Imag: 6069 case UnaryOperator::Extension: 6070 return getPrimaryDecl(UO->getSubExpr()); 6071 default: 6072 return 0; 6073 } 6074 } 6075 case Stmt::ParenExprClass: 6076 return getPrimaryDecl(cast<ParenExpr>(E)->getSubExpr()); 6077 case Stmt::ImplicitCastExprClass: 6078 // If the result of an implicit cast is an l-value, we care about 6079 // the sub-expression; otherwise, the result here doesn't matter. 6080 return getPrimaryDecl(cast<ImplicitCastExpr>(E)->getSubExpr()); 6081 default: 6082 return 0; 6083 } 6084} 6085 6086/// CheckAddressOfOperand - The operand of & must be either a function 6087/// designator or an lvalue designating an object. If it is an lvalue, the 6088/// object cannot be declared with storage class register or be a bit field. 6089/// Note: The usual conversions are *not* applied to the operand of the & 6090/// operator (C99 6.3.2.1p[2-4]), and its result is never an lvalue. 6091/// In C++, the operand might be an overloaded function name, in which case 6092/// we allow the '&' but retain the overloaded-function type. 6093QualType Sema::CheckAddressOfOperand(Expr *op, SourceLocation OpLoc) { 6094 // Make sure to ignore parentheses in subsequent checks 6095 op = op->IgnoreParens(); 6096 6097 if (op->isTypeDependent()) 6098 return Context.DependentTy; 6099 6100 if (getLangOptions().C99) { 6101 // Implement C99-only parts of addressof rules. 6102 if (UnaryOperator* uOp = dyn_cast<UnaryOperator>(op)) { 6103 if (uOp->getOpcode() == UnaryOperator::Deref) 6104 // Per C99 6.5.3.2, the address of a deref always returns a valid result 6105 // (assuming the deref expression is valid). 6106 return uOp->getSubExpr()->getType(); 6107 } 6108 // Technically, there should be a check for array subscript 6109 // expressions here, but the result of one is always an lvalue anyway. 6110 } 6111 NamedDecl *dcl = getPrimaryDecl(op); 6112 Expr::isLvalueResult lval = op->isLvalue(Context); 6113 6114 MemberExpr *ME = dyn_cast<MemberExpr>(op); 6115 if (lval == Expr::LV_MemberFunction && ME && 6116 isa<CXXMethodDecl>(ME->getMemberDecl())) { 6117 ValueDecl *dcl = cast<MemberExpr>(op)->getMemberDecl(); 6118 // &f where f is a member of the current object, or &o.f, or &p->f 6119 // All these are not allowed, and we need to catch them before the dcl 6120 // branch of the if, below. 6121 Diag(OpLoc, diag::err_unqualified_pointer_member_function) 6122 << dcl; 6123 // FIXME: Improve this diagnostic and provide a fixit. 6124 6125 // Now recover by acting as if the function had been accessed qualified. 6126 return Context.getMemberPointerType(op->getType(), 6127 Context.getTypeDeclType(cast<RecordDecl>(dcl->getDeclContext())) 6128 .getTypePtr()); 6129 } 6130 6131 if (lval == Expr::LV_ClassTemporary) { 6132 Diag(OpLoc, isSFINAEContext()? diag::err_typecheck_addrof_class_temporary 6133 : diag::ext_typecheck_addrof_class_temporary) 6134 << op->getType() << op->getSourceRange(); 6135 if (isSFINAEContext()) 6136 return QualType(); 6137 } else if (isa<ObjCSelectorExpr>(op)) 6138 return Context.getPointerType(op->getType()); 6139 else if (lval != Expr::LV_Valid && lval != Expr::LV_IncompleteVoidType) { 6140 // C99 6.5.3.2p1 6141 // The operand must be either an l-value or a function designator 6142 if (!op->getType()->isFunctionType()) { 6143 // FIXME: emit more specific diag... 6144 Diag(OpLoc, diag::err_typecheck_invalid_lvalue_addrof) 6145 << op->getSourceRange(); 6146 return QualType(); 6147 } 6148 } else if (op->getBitField()) { // C99 6.5.3.2p1 6149 // The operand cannot be a bit-field 6150 Diag(OpLoc, diag::err_typecheck_address_of) 6151 << "bit-field" << op->getSourceRange(); 6152 return QualType(); 6153 } else if (op->refersToVectorElement()) { 6154 // The operand cannot be an element of a vector 6155 Diag(OpLoc, diag::err_typecheck_address_of) 6156 << "vector element" << op->getSourceRange(); 6157 return QualType(); 6158 } else if (isa<ObjCPropertyRefExpr>(op)) { 6159 // cannot take address of a property expression. 6160 Diag(OpLoc, diag::err_typecheck_address_of) 6161 << "property expression" << op->getSourceRange(); 6162 return QualType(); 6163 } else if (ConditionalOperator *CO = dyn_cast<ConditionalOperator>(op)) { 6164 // FIXME: Can LHS ever be null here? 6165 if (!CheckAddressOfOperand(CO->getTrueExpr(), OpLoc).isNull()) 6166 return CheckAddressOfOperand(CO->getFalseExpr(), OpLoc); 6167 } else if (isa<UnresolvedLookupExpr>(op)) { 6168 return Context.OverloadTy; 6169 } else if (dcl) { // C99 6.5.3.2p1 6170 // We have an lvalue with a decl. Make sure the decl is not declared 6171 // with the register storage-class specifier. 6172 if (const VarDecl *vd = dyn_cast<VarDecl>(dcl)) { 6173 if (vd->getStorageClass() == VarDecl::Register) { 6174 Diag(OpLoc, diag::err_typecheck_address_of) 6175 << "register variable" << op->getSourceRange(); 6176 return QualType(); 6177 } 6178 } else if (isa<FunctionTemplateDecl>(dcl)) { 6179 return Context.OverloadTy; 6180 } else if (FieldDecl *FD = dyn_cast<FieldDecl>(dcl)) { 6181 // Okay: we can take the address of a field. 6182 // Could be a pointer to member, though, if there is an explicit 6183 // scope qualifier for the class. 6184 if (isa<DeclRefExpr>(op) && cast<DeclRefExpr>(op)->getQualifier()) { 6185 DeclContext *Ctx = dcl->getDeclContext(); 6186 if (Ctx && Ctx->isRecord()) { 6187 if (FD->getType()->isReferenceType()) { 6188 Diag(OpLoc, 6189 diag::err_cannot_form_pointer_to_member_of_reference_type) 6190 << FD->getDeclName() << FD->getType(); 6191 return QualType(); 6192 } 6193 6194 return Context.getMemberPointerType(op->getType(), 6195 Context.getTypeDeclType(cast<RecordDecl>(Ctx)).getTypePtr()); 6196 } 6197 } 6198 } else if (CXXMethodDecl *MD = dyn_cast<CXXMethodDecl>(dcl)) { 6199 // Okay: we can take the address of a function. 6200 // As above. 6201 if (isa<DeclRefExpr>(op) && cast<DeclRefExpr>(op)->getQualifier() && 6202 MD->isInstance()) 6203 return Context.getMemberPointerType(op->getType(), 6204 Context.getTypeDeclType(MD->getParent()).getTypePtr()); 6205 } else if (!isa<FunctionDecl>(dcl)) 6206 assert(0 && "Unknown/unexpected decl type"); 6207 } 6208 6209 if (lval == Expr::LV_IncompleteVoidType) { 6210 // Taking the address of a void variable is technically illegal, but we 6211 // allow it in cases which are otherwise valid. 6212 // Example: "extern void x; void* y = &x;". 6213 Diag(OpLoc, diag::ext_typecheck_addrof_void) << op->getSourceRange(); 6214 } 6215 6216 // If the operand has type "type", the result has type "pointer to type". 6217 return Context.getPointerType(op->getType()); 6218} 6219 6220/// CheckIndirectionOperand - Type check unary indirection (prefix '*'). 6221QualType Sema::CheckIndirectionOperand(Expr *Op, SourceLocation OpLoc) { 6222 if (Op->isTypeDependent()) 6223 return Context.DependentTy; 6224 6225 UsualUnaryConversions(Op); 6226 QualType OpTy = Op->getType(); 6227 QualType Result; 6228 6229 // Note that per both C89 and C99, indirection is always legal, even if OpTy 6230 // is an incomplete type or void. It would be possible to warn about 6231 // dereferencing a void pointer, but it's completely well-defined, and such a 6232 // warning is unlikely to catch any mistakes. 6233 if (const PointerType *PT = OpTy->getAs<PointerType>()) 6234 Result = PT->getPointeeType(); 6235 else if (const ObjCObjectPointerType *OPT = 6236 OpTy->getAs<ObjCObjectPointerType>()) 6237 Result = OPT->getPointeeType(); 6238 6239 if (Result.isNull()) { 6240 Diag(OpLoc, diag::err_typecheck_indirection_requires_pointer) 6241 << OpTy << Op->getSourceRange(); 6242 return QualType(); 6243 } 6244 6245 return Result; 6246} 6247 6248static inline BinaryOperator::Opcode ConvertTokenKindToBinaryOpcode( 6249 tok::TokenKind Kind) { 6250 BinaryOperator::Opcode Opc; 6251 switch (Kind) { 6252 default: assert(0 && "Unknown binop!"); 6253 case tok::periodstar: Opc = BinaryOperator::PtrMemD; break; 6254 case tok::arrowstar: Opc = BinaryOperator::PtrMemI; break; 6255 case tok::star: Opc = BinaryOperator::Mul; break; 6256 case tok::slash: Opc = BinaryOperator::Div; break; 6257 case tok::percent: Opc = BinaryOperator::Rem; break; 6258 case tok::plus: Opc = BinaryOperator::Add; break; 6259 case tok::minus: Opc = BinaryOperator::Sub; break; 6260 case tok::lessless: Opc = BinaryOperator::Shl; break; 6261 case tok::greatergreater: Opc = BinaryOperator::Shr; break; 6262 case tok::lessequal: Opc = BinaryOperator::LE; break; 6263 case tok::less: Opc = BinaryOperator::LT; break; 6264 case tok::greaterequal: Opc = BinaryOperator::GE; break; 6265 case tok::greater: Opc = BinaryOperator::GT; break; 6266 case tok::exclaimequal: Opc = BinaryOperator::NE; break; 6267 case tok::equalequal: Opc = BinaryOperator::EQ; break; 6268 case tok::amp: Opc = BinaryOperator::And; break; 6269 case tok::caret: Opc = BinaryOperator::Xor; break; 6270 case tok::pipe: Opc = BinaryOperator::Or; break; 6271 case tok::ampamp: Opc = BinaryOperator::LAnd; break; 6272 case tok::pipepipe: Opc = BinaryOperator::LOr; break; 6273 case tok::equal: Opc = BinaryOperator::Assign; break; 6274 case tok::starequal: Opc = BinaryOperator::MulAssign; break; 6275 case tok::slashequal: Opc = BinaryOperator::DivAssign; break; 6276 case tok::percentequal: Opc = BinaryOperator::RemAssign; break; 6277 case tok::plusequal: Opc = BinaryOperator::AddAssign; break; 6278 case tok::minusequal: Opc = BinaryOperator::SubAssign; break; 6279 case tok::lesslessequal: Opc = BinaryOperator::ShlAssign; break; 6280 case tok::greatergreaterequal: Opc = BinaryOperator::ShrAssign; break; 6281 case tok::ampequal: Opc = BinaryOperator::AndAssign; break; 6282 case tok::caretequal: Opc = BinaryOperator::XorAssign; break; 6283 case tok::pipeequal: Opc = BinaryOperator::OrAssign; break; 6284 case tok::comma: Opc = BinaryOperator::Comma; break; 6285 } 6286 return Opc; 6287} 6288 6289static inline UnaryOperator::Opcode ConvertTokenKindToUnaryOpcode( 6290 tok::TokenKind Kind) { 6291 UnaryOperator::Opcode Opc; 6292 switch (Kind) { 6293 default: assert(0 && "Unknown unary op!"); 6294 case tok::plusplus: Opc = UnaryOperator::PreInc; break; 6295 case tok::minusminus: Opc = UnaryOperator::PreDec; break; 6296 case tok::amp: Opc = UnaryOperator::AddrOf; break; 6297 case tok::star: Opc = UnaryOperator::Deref; break; 6298 case tok::plus: Opc = UnaryOperator::Plus; break; 6299 case tok::minus: Opc = UnaryOperator::Minus; break; 6300 case tok::tilde: Opc = UnaryOperator::Not; break; 6301 case tok::exclaim: Opc = UnaryOperator::LNot; break; 6302 case tok::kw___real: Opc = UnaryOperator::Real; break; 6303 case tok::kw___imag: Opc = UnaryOperator::Imag; break; 6304 case tok::kw___extension__: Opc = UnaryOperator::Extension; break; 6305 } 6306 return Opc; 6307} 6308 6309/// CreateBuiltinBinOp - Creates a new built-in binary operation with 6310/// operator @p Opc at location @c TokLoc. This routine only supports 6311/// built-in operations; ActOnBinOp handles overloaded operators. 6312Action::OwningExprResult Sema::CreateBuiltinBinOp(SourceLocation OpLoc, 6313 unsigned Op, 6314 Expr *lhs, Expr *rhs) { 6315 QualType ResultTy; // Result type of the binary operator. 6316 BinaryOperator::Opcode Opc = (BinaryOperator::Opcode)Op; 6317 // The following two variables are used for compound assignment operators 6318 QualType CompLHSTy; // Type of LHS after promotions for computation 6319 QualType CompResultTy; // Type of computation result 6320 6321 switch (Opc) { 6322 case BinaryOperator::Assign: 6323 ResultTy = CheckAssignmentOperands(lhs, rhs, OpLoc, QualType()); 6324 break; 6325 case BinaryOperator::PtrMemD: 6326 case BinaryOperator::PtrMemI: 6327 ResultTy = CheckPointerToMemberOperands(lhs, rhs, OpLoc, 6328 Opc == BinaryOperator::PtrMemI); 6329 break; 6330 case BinaryOperator::Mul: 6331 case BinaryOperator::Div: 6332 ResultTy = CheckMultiplyDivideOperands(lhs, rhs, OpLoc, false, 6333 Opc == BinaryOperator::Div); 6334 break; 6335 case BinaryOperator::Rem: 6336 ResultTy = CheckRemainderOperands(lhs, rhs, OpLoc); 6337 break; 6338 case BinaryOperator::Add: 6339 ResultTy = CheckAdditionOperands(lhs, rhs, OpLoc); 6340 break; 6341 case BinaryOperator::Sub: 6342 ResultTy = CheckSubtractionOperands(lhs, rhs, OpLoc); 6343 break; 6344 case BinaryOperator::Shl: 6345 case BinaryOperator::Shr: 6346 ResultTy = CheckShiftOperands(lhs, rhs, OpLoc); 6347 break; 6348 case BinaryOperator::LE: 6349 case BinaryOperator::LT: 6350 case BinaryOperator::GE: 6351 case BinaryOperator::GT: 6352 ResultTy = CheckCompareOperands(lhs, rhs, OpLoc, Opc, true); 6353 break; 6354 case BinaryOperator::EQ: 6355 case BinaryOperator::NE: 6356 ResultTy = CheckCompareOperands(lhs, rhs, OpLoc, Opc, false); 6357 break; 6358 case BinaryOperator::And: 6359 case BinaryOperator::Xor: 6360 case BinaryOperator::Or: 6361 ResultTy = CheckBitwiseOperands(lhs, rhs, OpLoc); 6362 break; 6363 case BinaryOperator::LAnd: 6364 case BinaryOperator::LOr: 6365 ResultTy = CheckLogicalOperands(lhs, rhs, OpLoc); 6366 break; 6367 case BinaryOperator::MulAssign: 6368 case BinaryOperator::DivAssign: 6369 CompResultTy = CheckMultiplyDivideOperands(lhs, rhs, OpLoc, true, 6370 Opc == BinaryOperator::DivAssign); 6371 CompLHSTy = CompResultTy; 6372 if (!CompResultTy.isNull()) 6373 ResultTy = CheckAssignmentOperands(lhs, rhs, OpLoc, CompResultTy); 6374 break; 6375 case BinaryOperator::RemAssign: 6376 CompResultTy = CheckRemainderOperands(lhs, rhs, OpLoc, true); 6377 CompLHSTy = CompResultTy; 6378 if (!CompResultTy.isNull()) 6379 ResultTy = CheckAssignmentOperands(lhs, rhs, OpLoc, CompResultTy); 6380 break; 6381 case BinaryOperator::AddAssign: 6382 CompResultTy = CheckAdditionOperands(lhs, rhs, OpLoc, &CompLHSTy); 6383 if (!CompResultTy.isNull()) 6384 ResultTy = CheckAssignmentOperands(lhs, rhs, OpLoc, CompResultTy); 6385 break; 6386 case BinaryOperator::SubAssign: 6387 CompResultTy = CheckSubtractionOperands(lhs, rhs, OpLoc, &CompLHSTy); 6388 if (!CompResultTy.isNull()) 6389 ResultTy = CheckAssignmentOperands(lhs, rhs, OpLoc, CompResultTy); 6390 break; 6391 case BinaryOperator::ShlAssign: 6392 case BinaryOperator::ShrAssign: 6393 CompResultTy = CheckShiftOperands(lhs, rhs, OpLoc, true); 6394 CompLHSTy = CompResultTy; 6395 if (!CompResultTy.isNull()) 6396 ResultTy = CheckAssignmentOperands(lhs, rhs, OpLoc, CompResultTy); 6397 break; 6398 case BinaryOperator::AndAssign: 6399 case BinaryOperator::XorAssign: 6400 case BinaryOperator::OrAssign: 6401 CompResultTy = CheckBitwiseOperands(lhs, rhs, OpLoc, true); 6402 CompLHSTy = CompResultTy; 6403 if (!CompResultTy.isNull()) 6404 ResultTy = CheckAssignmentOperands(lhs, rhs, OpLoc, CompResultTy); 6405 break; 6406 case BinaryOperator::Comma: 6407 ResultTy = CheckCommaOperands(lhs, rhs, OpLoc); 6408 break; 6409 } 6410 if (ResultTy.isNull()) 6411 return ExprError(); 6412 if (CompResultTy.isNull()) 6413 return Owned(new (Context) BinaryOperator(lhs, rhs, Opc, ResultTy, OpLoc)); 6414 else 6415 return Owned(new (Context) CompoundAssignOperator(lhs, rhs, Opc, ResultTy, 6416 CompLHSTy, CompResultTy, 6417 OpLoc)); 6418} 6419 6420/// SuggestParentheses - Emit a diagnostic together with a fixit hint that wraps 6421/// ParenRange in parentheses. 6422static void SuggestParentheses(Sema &Self, SourceLocation Loc, 6423 const PartialDiagnostic &PD, 6424 const PartialDiagnostic &FirstNote, 6425 SourceRange FirstParenRange, 6426 const PartialDiagnostic &SecondNote, 6427 SourceRange SecondParenRange) { 6428 Self.Diag(Loc, PD); 6429 6430 if (!FirstNote.getDiagID()) 6431 return; 6432 6433 SourceLocation EndLoc = Self.PP.getLocForEndOfToken(FirstParenRange.getEnd()); 6434 if (!FirstParenRange.getEnd().isFileID() || EndLoc.isInvalid()) { 6435 // We can't display the parentheses, so just return. 6436 return; 6437 } 6438 6439 Self.Diag(Loc, FirstNote) 6440 << FixItHint::CreateInsertion(FirstParenRange.getBegin(), "(") 6441 << FixItHint::CreateInsertion(EndLoc, ")"); 6442 6443 if (!SecondNote.getDiagID()) 6444 return; 6445 6446 EndLoc = Self.PP.getLocForEndOfToken(SecondParenRange.getEnd()); 6447 if (!SecondParenRange.getEnd().isFileID() || EndLoc.isInvalid()) { 6448 // We can't display the parentheses, so just dig the 6449 // warning/error and return. 6450 Self.Diag(Loc, SecondNote); 6451 return; 6452 } 6453 6454 Self.Diag(Loc, SecondNote) 6455 << FixItHint::CreateInsertion(SecondParenRange.getBegin(), "(") 6456 << FixItHint::CreateInsertion(EndLoc, ")"); 6457} 6458 6459/// DiagnoseBitwisePrecedence - Emit a warning when bitwise and comparison 6460/// operators are mixed in a way that suggests that the programmer forgot that 6461/// comparison operators have higher precedence. The most typical example of 6462/// such code is "flags & 0x0020 != 0", which is equivalent to "flags & 1". 6463static void DiagnoseBitwisePrecedence(Sema &Self, BinaryOperator::Opcode Opc, 6464 SourceLocation OpLoc,Expr *lhs,Expr *rhs){ 6465 typedef BinaryOperator BinOp; 6466 BinOp::Opcode lhsopc = static_cast<BinOp::Opcode>(-1), 6467 rhsopc = static_cast<BinOp::Opcode>(-1); 6468 if (BinOp *BO = dyn_cast<BinOp>(lhs)) 6469 lhsopc = BO->getOpcode(); 6470 if (BinOp *BO = dyn_cast<BinOp>(rhs)) 6471 rhsopc = BO->getOpcode(); 6472 6473 // Subs are not binary operators. 6474 if (lhsopc == -1 && rhsopc == -1) 6475 return; 6476 6477 // Bitwise operations are sometimes used as eager logical ops. 6478 // Don't diagnose this. 6479 if ((BinOp::isComparisonOp(lhsopc) || BinOp::isBitwiseOp(lhsopc)) && 6480 (BinOp::isComparisonOp(rhsopc) || BinOp::isBitwiseOp(rhsopc))) 6481 return; 6482 6483 if (BinOp::isComparisonOp(lhsopc)) 6484 SuggestParentheses(Self, OpLoc, 6485 Self.PDiag(diag::warn_precedence_bitwise_rel) 6486 << SourceRange(lhs->getLocStart(), OpLoc) 6487 << BinOp::getOpcodeStr(Opc) << BinOp::getOpcodeStr(lhsopc), 6488 Self.PDiag(diag::note_precedence_bitwise_first) 6489 << BinOp::getOpcodeStr(Opc), 6490 SourceRange(cast<BinOp>(lhs)->getRHS()->getLocStart(), rhs->getLocEnd()), 6491 Self.PDiag(diag::note_precedence_bitwise_silence) 6492 << BinOp::getOpcodeStr(lhsopc), 6493 lhs->getSourceRange()); 6494 else if (BinOp::isComparisonOp(rhsopc)) 6495 SuggestParentheses(Self, OpLoc, 6496 Self.PDiag(diag::warn_precedence_bitwise_rel) 6497 << SourceRange(OpLoc, rhs->getLocEnd()) 6498 << BinOp::getOpcodeStr(Opc) << BinOp::getOpcodeStr(rhsopc), 6499 Self.PDiag(diag::note_precedence_bitwise_first) 6500 << BinOp::getOpcodeStr(Opc), 6501 SourceRange(lhs->getLocEnd(), cast<BinOp>(rhs)->getLHS()->getLocStart()), 6502 Self.PDiag(diag::note_precedence_bitwise_silence) 6503 << BinOp::getOpcodeStr(rhsopc), 6504 rhs->getSourceRange()); 6505} 6506 6507/// DiagnoseBinOpPrecedence - Emit warnings for expressions with tricky 6508/// precedence. This currently diagnoses only "arg1 'bitwise' arg2 'eq' arg3". 6509/// But it could also warn about arg1 && arg2 || arg3, as GCC 4.3+ does. 6510static void DiagnoseBinOpPrecedence(Sema &Self, BinaryOperator::Opcode Opc, 6511 SourceLocation OpLoc, Expr *lhs, Expr *rhs){ 6512 if (BinaryOperator::isBitwiseOp(Opc)) 6513 DiagnoseBitwisePrecedence(Self, Opc, OpLoc, lhs, rhs); 6514} 6515 6516// Binary Operators. 'Tok' is the token for the operator. 6517Action::OwningExprResult Sema::ActOnBinOp(Scope *S, SourceLocation TokLoc, 6518 tok::TokenKind Kind, 6519 ExprArg LHS, ExprArg RHS) { 6520 BinaryOperator::Opcode Opc = ConvertTokenKindToBinaryOpcode(Kind); 6521 Expr *lhs = LHS.takeAs<Expr>(), *rhs = RHS.takeAs<Expr>(); 6522 6523 assert((lhs != 0) && "ActOnBinOp(): missing left expression"); 6524 assert((rhs != 0) && "ActOnBinOp(): missing right expression"); 6525 6526 // Emit warnings for tricky precedence issues, e.g. "bitfield & 0x4 == 0" 6527 DiagnoseBinOpPrecedence(*this, Opc, TokLoc, lhs, rhs); 6528 6529 return BuildBinOp(S, TokLoc, Opc, lhs, rhs); 6530} 6531 6532Action::OwningExprResult Sema::BuildBinOp(Scope *S, SourceLocation OpLoc, 6533 BinaryOperator::Opcode Opc, 6534 Expr *lhs, Expr *rhs) { 6535 if (getLangOptions().CPlusPlus && 6536 (lhs->getType()->isOverloadableType() || 6537 rhs->getType()->isOverloadableType())) { 6538 // Find all of the overloaded operators visible from this 6539 // point. We perform both an operator-name lookup from the local 6540 // scope and an argument-dependent lookup based on the types of 6541 // the arguments. 6542 UnresolvedSet<16> Functions; 6543 OverloadedOperatorKind OverOp = BinaryOperator::getOverloadedOperator(Opc); 6544 if (S && OverOp != OO_None) 6545 LookupOverloadedOperatorName(OverOp, S, lhs->getType(), rhs->getType(), 6546 Functions); 6547 6548 // Build the (potentially-overloaded, potentially-dependent) 6549 // binary operation. 6550 return CreateOverloadedBinOp(OpLoc, Opc, Functions, lhs, rhs); 6551 } 6552 6553 // Build a built-in binary operation. 6554 return CreateBuiltinBinOp(OpLoc, Opc, lhs, rhs); 6555} 6556 6557Action::OwningExprResult Sema::CreateBuiltinUnaryOp(SourceLocation OpLoc, 6558 unsigned OpcIn, 6559 ExprArg InputArg) { 6560 UnaryOperator::Opcode Opc = static_cast<UnaryOperator::Opcode>(OpcIn); 6561 6562 // FIXME: Input is modified below, but InputArg is not updated appropriately. 6563 Expr *Input = (Expr *)InputArg.get(); 6564 QualType resultType; 6565 switch (Opc) { 6566 case UnaryOperator::OffsetOf: 6567 assert(false && "Invalid unary operator"); 6568 break; 6569 6570 case UnaryOperator::PreInc: 6571 case UnaryOperator::PreDec: 6572 case UnaryOperator::PostInc: 6573 case UnaryOperator::PostDec: 6574 resultType = CheckIncrementDecrementOperand(Input, OpLoc, 6575 Opc == UnaryOperator::PreInc || 6576 Opc == UnaryOperator::PostInc, 6577 Opc == UnaryOperator::PreInc || 6578 Opc == UnaryOperator::PreDec); 6579 break; 6580 case UnaryOperator::AddrOf: 6581 resultType = CheckAddressOfOperand(Input, OpLoc); 6582 break; 6583 case UnaryOperator::Deref: 6584 DefaultFunctionArrayLvalueConversion(Input); 6585 resultType = CheckIndirectionOperand(Input, OpLoc); 6586 break; 6587 case UnaryOperator::Plus: 6588 case UnaryOperator::Minus: 6589 UsualUnaryConversions(Input); 6590 resultType = Input->getType(); 6591 if (resultType->isDependentType()) 6592 break; 6593 if (resultType->isArithmeticType() || // C99 6.5.3.3p1 6594 resultType->isVectorType()) 6595 break; 6596 else if (getLangOptions().CPlusPlus && // C++ [expr.unary.op]p6-7 6597 resultType->isEnumeralType()) 6598 break; 6599 else if (getLangOptions().CPlusPlus && // C++ [expr.unary.op]p6 6600 Opc == UnaryOperator::Plus && 6601 resultType->isPointerType()) 6602 break; 6603 6604 return ExprError(Diag(OpLoc, diag::err_typecheck_unary_expr) 6605 << resultType << Input->getSourceRange()); 6606 case UnaryOperator::Not: // bitwise complement 6607 UsualUnaryConversions(Input); 6608 resultType = Input->getType(); 6609 if (resultType->isDependentType()) 6610 break; 6611 // C99 6.5.3.3p1. We allow complex int and float as a GCC extension. 6612 if (resultType->isComplexType() || resultType->isComplexIntegerType()) 6613 // C99 does not support '~' for complex conjugation. 6614 Diag(OpLoc, diag::ext_integer_complement_complex) 6615 << resultType << Input->getSourceRange(); 6616 else if (!resultType->isIntegerType()) 6617 return ExprError(Diag(OpLoc, diag::err_typecheck_unary_expr) 6618 << resultType << Input->getSourceRange()); 6619 break; 6620 case UnaryOperator::LNot: // logical negation 6621 // Unlike +/-/~, integer promotions aren't done here (C99 6.5.3.3p5). 6622 DefaultFunctionArrayLvalueConversion(Input); 6623 resultType = Input->getType(); 6624 if (resultType->isDependentType()) 6625 break; 6626 if (!resultType->isScalarType()) // C99 6.5.3.3p1 6627 return ExprError(Diag(OpLoc, diag::err_typecheck_unary_expr) 6628 << resultType << Input->getSourceRange()); 6629 // LNot always has type int. C99 6.5.3.3p5. 6630 // In C++, it's bool. C++ 5.3.1p8 6631 resultType = getLangOptions().CPlusPlus ? Context.BoolTy : Context.IntTy; 6632 break; 6633 case UnaryOperator::Real: 6634 case UnaryOperator::Imag: 6635 resultType = CheckRealImagOperand(Input, OpLoc, Opc == UnaryOperator::Real); 6636 break; 6637 case UnaryOperator::Extension: 6638 resultType = Input->getType(); 6639 break; 6640 } 6641 if (resultType.isNull()) 6642 return ExprError(); 6643 6644 InputArg.release(); 6645 return Owned(new (Context) UnaryOperator(Input, Opc, resultType, OpLoc)); 6646} 6647 6648Action::OwningExprResult Sema::BuildUnaryOp(Scope *S, SourceLocation OpLoc, 6649 UnaryOperator::Opcode Opc, 6650 ExprArg input) { 6651 Expr *Input = (Expr*)input.get(); 6652 if (getLangOptions().CPlusPlus && Input->getType()->isOverloadableType() && 6653 Opc != UnaryOperator::Extension) { 6654 // Find all of the overloaded operators visible from this 6655 // point. We perform both an operator-name lookup from the local 6656 // scope and an argument-dependent lookup based on the types of 6657 // the arguments. 6658 UnresolvedSet<16> Functions; 6659 OverloadedOperatorKind OverOp = UnaryOperator::getOverloadedOperator(Opc); 6660 if (S && OverOp != OO_None) 6661 LookupOverloadedOperatorName(OverOp, S, Input->getType(), QualType(), 6662 Functions); 6663 6664 return CreateOverloadedUnaryOp(OpLoc, Opc, Functions, move(input)); 6665 } 6666 6667 return CreateBuiltinUnaryOp(OpLoc, Opc, move(input)); 6668} 6669 6670// Unary Operators. 'Tok' is the token for the operator. 6671Action::OwningExprResult Sema::ActOnUnaryOp(Scope *S, SourceLocation OpLoc, 6672 tok::TokenKind Op, ExprArg input) { 6673 return BuildUnaryOp(S, OpLoc, ConvertTokenKindToUnaryOpcode(Op), move(input)); 6674} 6675 6676/// ActOnAddrLabel - Parse the GNU address of label extension: "&&foo". 6677Sema::OwningExprResult Sema::ActOnAddrLabel(SourceLocation OpLoc, 6678 SourceLocation LabLoc, 6679 IdentifierInfo *LabelII) { 6680 // Look up the record for this label identifier. 6681 LabelStmt *&LabelDecl = getLabelMap()[LabelII]; 6682 6683 // If we haven't seen this label yet, create a forward reference. It 6684 // will be validated and/or cleaned up in ActOnFinishFunctionBody. 6685 if (LabelDecl == 0) 6686 LabelDecl = new (Context) LabelStmt(LabLoc, LabelII, 0); 6687 6688 // Create the AST node. The address of a label always has type 'void*'. 6689 return Owned(new (Context) AddrLabelExpr(OpLoc, LabLoc, LabelDecl, 6690 Context.getPointerType(Context.VoidTy))); 6691} 6692 6693Sema::OwningExprResult 6694Sema::ActOnStmtExpr(SourceLocation LPLoc, StmtArg substmt, 6695 SourceLocation RPLoc) { // "({..})" 6696 Stmt *SubStmt = static_cast<Stmt*>(substmt.get()); 6697 assert(SubStmt && isa<CompoundStmt>(SubStmt) && "Invalid action invocation!"); 6698 CompoundStmt *Compound = cast<CompoundStmt>(SubStmt); 6699 6700 bool isFileScope 6701 = (getCurFunctionOrMethodDecl() == 0) && (getCurBlock() == 0); 6702 if (isFileScope) 6703 return ExprError(Diag(LPLoc, diag::err_stmtexpr_file_scope)); 6704 6705 // FIXME: there are a variety of strange constraints to enforce here, for 6706 // example, it is not possible to goto into a stmt expression apparently. 6707 // More semantic analysis is needed. 6708 6709 // If there are sub stmts in the compound stmt, take the type of the last one 6710 // as the type of the stmtexpr. 6711 QualType Ty = Context.VoidTy; 6712 6713 if (!Compound->body_empty()) { 6714 Stmt *LastStmt = Compound->body_back(); 6715 // If LastStmt is a label, skip down through into the body. 6716 while (LabelStmt *Label = dyn_cast<LabelStmt>(LastStmt)) 6717 LastStmt = Label->getSubStmt(); 6718 6719 if (Expr *LastExpr = dyn_cast<Expr>(LastStmt)) 6720 Ty = LastExpr->getType(); 6721 } 6722 6723 // FIXME: Check that expression type is complete/non-abstract; statement 6724 // expressions are not lvalues. 6725 6726 substmt.release(); 6727 return Owned(new (Context) StmtExpr(Compound, Ty, LPLoc, RPLoc)); 6728} 6729 6730Sema::OwningExprResult Sema::BuildBuiltinOffsetOf(SourceLocation BuiltinLoc, 6731 TypeSourceInfo *TInfo, 6732 OffsetOfComponent *CompPtr, 6733 unsigned NumComponents, 6734 SourceLocation RParenLoc) { 6735 QualType ArgTy = TInfo->getType(); 6736 bool Dependent = ArgTy->isDependentType(); 6737 SourceRange TypeRange = TInfo->getTypeLoc().getLocalSourceRange(); 6738 6739 // We must have at least one component that refers to the type, and the first 6740 // one is known to be a field designator. Verify that the ArgTy represents 6741 // a struct/union/class. 6742 if (!Dependent && !ArgTy->isRecordType()) 6743 return ExprError(Diag(BuiltinLoc, diag::err_offsetof_record_type) 6744 << ArgTy << TypeRange); 6745 6746 // Type must be complete per C99 7.17p3 because a declaring a variable 6747 // with an incomplete type would be ill-formed. 6748 if (!Dependent 6749 && RequireCompleteType(BuiltinLoc, ArgTy, 6750 PDiag(diag::err_offsetof_incomplete_type) 6751 << TypeRange)) 6752 return ExprError(); 6753 6754 // offsetof with non-identifier designators (e.g. "offsetof(x, a.b[c])") are a 6755 // GCC extension, diagnose them. 6756 // FIXME: This diagnostic isn't actually visible because the location is in 6757 // a system header! 6758 if (NumComponents != 1) 6759 Diag(BuiltinLoc, diag::ext_offsetof_extended_field_designator) 6760 << SourceRange(CompPtr[1].LocStart, CompPtr[NumComponents-1].LocEnd); 6761 6762 bool DidWarnAboutNonPOD = false; 6763 QualType CurrentType = ArgTy; 6764 typedef OffsetOfExpr::OffsetOfNode OffsetOfNode; 6765 llvm::SmallVector<OffsetOfNode, 4> Comps; 6766 llvm::SmallVector<Expr*, 4> Exprs; 6767 for (unsigned i = 0; i != NumComponents; ++i) { 6768 const OffsetOfComponent &OC = CompPtr[i]; 6769 if (OC.isBrackets) { 6770 // Offset of an array sub-field. TODO: Should we allow vector elements? 6771 if (!CurrentType->isDependentType()) { 6772 const ArrayType *AT = Context.getAsArrayType(CurrentType); 6773 if(!AT) 6774 return ExprError(Diag(OC.LocEnd, diag::err_offsetof_array_type) 6775 << CurrentType); 6776 CurrentType = AT->getElementType(); 6777 } else 6778 CurrentType = Context.DependentTy; 6779 6780 // The expression must be an integral expression. 6781 // FIXME: An integral constant expression? 6782 Expr *Idx = static_cast<Expr*>(OC.U.E); 6783 if (!Idx->isTypeDependent() && !Idx->isValueDependent() && 6784 !Idx->getType()->isIntegerType()) 6785 return ExprError(Diag(Idx->getLocStart(), 6786 diag::err_typecheck_subscript_not_integer) 6787 << Idx->getSourceRange()); 6788 6789 // Record this array index. 6790 Comps.push_back(OffsetOfNode(OC.LocStart, Exprs.size(), OC.LocEnd)); 6791 Exprs.push_back(Idx); 6792 continue; 6793 } 6794 6795 // Offset of a field. 6796 if (CurrentType->isDependentType()) { 6797 // We have the offset of a field, but we can't look into the dependent 6798 // type. Just record the identifier of the field. 6799 Comps.push_back(OffsetOfNode(OC.LocStart, OC.U.IdentInfo, OC.LocEnd)); 6800 CurrentType = Context.DependentTy; 6801 continue; 6802 } 6803 6804 // We need to have a complete type to look into. 6805 if (RequireCompleteType(OC.LocStart, CurrentType, 6806 diag::err_offsetof_incomplete_type)) 6807 return ExprError(); 6808 6809 // Look for the designated field. 6810 const RecordType *RC = CurrentType->getAs<RecordType>(); 6811 if (!RC) 6812 return ExprError(Diag(OC.LocEnd, diag::err_offsetof_record_type) 6813 << CurrentType); 6814 RecordDecl *RD = RC->getDecl(); 6815 6816 // C++ [lib.support.types]p5: 6817 // The macro offsetof accepts a restricted set of type arguments in this 6818 // International Standard. type shall be a POD structure or a POD union 6819 // (clause 9). 6820 if (CXXRecordDecl *CRD = dyn_cast<CXXRecordDecl>(RD)) { 6821 if (!CRD->isPOD() && !DidWarnAboutNonPOD && 6822 DiagRuntimeBehavior(BuiltinLoc, 6823 PDiag(diag::warn_offsetof_non_pod_type) 6824 << SourceRange(CompPtr[0].LocStart, OC.LocEnd) 6825 << CurrentType)) 6826 DidWarnAboutNonPOD = true; 6827 } 6828 6829 // Look for the field. 6830 LookupResult R(*this, OC.U.IdentInfo, OC.LocStart, LookupMemberName); 6831 LookupQualifiedName(R, RD); 6832 FieldDecl *MemberDecl = R.getAsSingle<FieldDecl>(); 6833 if (!MemberDecl) 6834 return ExprError(Diag(BuiltinLoc, diag::err_no_member) 6835 << OC.U.IdentInfo << RD << SourceRange(OC.LocStart, 6836 OC.LocEnd)); 6837 6838 // C99 7.17p3: 6839 // (If the specified member is a bit-field, the behavior is undefined.) 6840 // 6841 // We diagnose this as an error. 6842 if (MemberDecl->getBitWidth()) { 6843 Diag(OC.LocEnd, diag::err_offsetof_bitfield) 6844 << MemberDecl->getDeclName() 6845 << SourceRange(BuiltinLoc, RParenLoc); 6846 Diag(MemberDecl->getLocation(), diag::note_bitfield_decl); 6847 return ExprError(); 6848 } 6849 6850 // If the member was found in a base class, introduce OffsetOfNodes for 6851 // the base class indirections. 6852 CXXBasePaths Paths(/*FindAmbiguities=*/true, /*RecordPaths=*/true, 6853 /*DetectVirtual=*/false); 6854 if (IsDerivedFrom(CurrentType, 6855 Context.getTypeDeclType(MemberDecl->getParent()), 6856 Paths)) { 6857 CXXBasePath &Path = Paths.front(); 6858 for (CXXBasePath::iterator B = Path.begin(), BEnd = Path.end(); 6859 B != BEnd; ++B) 6860 Comps.push_back(OffsetOfNode(B->Base)); 6861 } 6862 6863 if (cast<RecordDecl>(MemberDecl->getDeclContext())-> 6864 isAnonymousStructOrUnion()) { 6865 llvm::SmallVector<FieldDecl*, 4> Path; 6866 BuildAnonymousStructUnionMemberPath(MemberDecl, Path); 6867 unsigned n = Path.size(); 6868 for (int j = n - 1; j > -1; --j) 6869 Comps.push_back(OffsetOfNode(OC.LocStart, Path[j], OC.LocEnd)); 6870 } else { 6871 Comps.push_back(OffsetOfNode(OC.LocStart, MemberDecl, OC.LocEnd)); 6872 } 6873 CurrentType = MemberDecl->getType().getNonReferenceType(); 6874 } 6875 6876 return Owned(OffsetOfExpr::Create(Context, Context.getSizeType(), BuiltinLoc, 6877 TInfo, Comps.data(), Comps.size(), 6878 Exprs.data(), Exprs.size(), RParenLoc)); 6879} 6880 6881Sema::OwningExprResult Sema::ActOnBuiltinOffsetOf(Scope *S, 6882 SourceLocation BuiltinLoc, 6883 SourceLocation TypeLoc, 6884 TypeTy *argty, 6885 OffsetOfComponent *CompPtr, 6886 unsigned NumComponents, 6887 SourceLocation RPLoc) { 6888 6889 TypeSourceInfo *ArgTInfo; 6890 QualType ArgTy = GetTypeFromParser(argty, &ArgTInfo); 6891 if (ArgTy.isNull()) 6892 return ExprError(); 6893 6894 if (getLangOptions().CPlusPlus) { 6895 if (!ArgTInfo) 6896 ArgTInfo = Context.getTrivialTypeSourceInfo(ArgTy, TypeLoc); 6897 6898 return BuildBuiltinOffsetOf(BuiltinLoc, ArgTInfo, CompPtr, NumComponents, 6899 RPLoc); 6900 } 6901 6902 // FIXME: The code below is marked for death, once we have proper CodeGen 6903 // support for non-constant OffsetOf expressions. 6904 6905 bool Dependent = ArgTy->isDependentType(); 6906 6907 // We must have at least one component that refers to the type, and the first 6908 // one is known to be a field designator. Verify that the ArgTy represents 6909 // a struct/union/class. 6910 if (!Dependent && !ArgTy->isRecordType()) 6911 return ExprError(Diag(TypeLoc, diag::err_offsetof_record_type) << ArgTy); 6912 6913 // FIXME: Type must be complete per C99 7.17p3 because a declaring a variable 6914 // with an incomplete type would be illegal. 6915 6916 // Otherwise, create a null pointer as the base, and iteratively process 6917 // the offsetof designators. 6918 QualType ArgTyPtr = Context.getPointerType(ArgTy); 6919 Expr* Res = new (Context) ImplicitValueInitExpr(ArgTyPtr); 6920 Res = new (Context) UnaryOperator(Res, UnaryOperator::Deref, 6921 ArgTy, SourceLocation()); 6922 6923 // offsetof with non-identifier designators (e.g. "offsetof(x, a.b[c])") are a 6924 // GCC extension, diagnose them. 6925 // FIXME: This diagnostic isn't actually visible because the location is in 6926 // a system header! 6927 if (NumComponents != 1) 6928 Diag(BuiltinLoc, diag::ext_offsetof_extended_field_designator) 6929 << SourceRange(CompPtr[1].LocStart, CompPtr[NumComponents-1].LocEnd); 6930 6931 if (!Dependent) { 6932 bool DidWarnAboutNonPOD = false; 6933 6934 if (RequireCompleteType(TypeLoc, Res->getType(), 6935 diag::err_offsetof_incomplete_type)) 6936 return ExprError(); 6937 6938 // FIXME: Dependent case loses a lot of information here. And probably 6939 // leaks like a sieve. 6940 for (unsigned i = 0; i != NumComponents; ++i) { 6941 const OffsetOfComponent &OC = CompPtr[i]; 6942 if (OC.isBrackets) { 6943 // Offset of an array sub-field. TODO: Should we allow vector elements? 6944 const ArrayType *AT = Context.getAsArrayType(Res->getType()); 6945 if (!AT) { 6946 Res->Destroy(Context); 6947 return ExprError(Diag(OC.LocEnd, diag::err_offsetof_array_type) 6948 << Res->getType()); 6949 } 6950 6951 // FIXME: C++: Verify that operator[] isn't overloaded. 6952 6953 // Promote the array so it looks more like a normal array subscript 6954 // expression. 6955 DefaultFunctionArrayLvalueConversion(Res); 6956 6957 // C99 6.5.2.1p1 6958 Expr *Idx = static_cast<Expr*>(OC.U.E); 6959 // FIXME: Leaks Res 6960 if (!Idx->isTypeDependent() && !Idx->getType()->isIntegerType()) 6961 return ExprError(Diag(Idx->getLocStart(), 6962 diag::err_typecheck_subscript_not_integer) 6963 << Idx->getSourceRange()); 6964 6965 Res = new (Context) ArraySubscriptExpr(Res, Idx, AT->getElementType(), 6966 OC.LocEnd); 6967 continue; 6968 } 6969 6970 const RecordType *RC = Res->getType()->getAs<RecordType>(); 6971 if (!RC) { 6972 Res->Destroy(Context); 6973 return ExprError(Diag(OC.LocEnd, diag::err_offsetof_record_type) 6974 << Res->getType()); 6975 } 6976 6977 // Get the decl corresponding to this. 6978 RecordDecl *RD = RC->getDecl(); 6979 if (CXXRecordDecl *CRD = dyn_cast<CXXRecordDecl>(RD)) { 6980 if (!CRD->isPOD() && !DidWarnAboutNonPOD && 6981 DiagRuntimeBehavior(BuiltinLoc, 6982 PDiag(diag::warn_offsetof_non_pod_type) 6983 << SourceRange(CompPtr[0].LocStart, OC.LocEnd) 6984 << Res->getType())) 6985 DidWarnAboutNonPOD = true; 6986 } 6987 6988 LookupResult R(*this, OC.U.IdentInfo, OC.LocStart, LookupMemberName); 6989 LookupQualifiedName(R, RD); 6990 6991 FieldDecl *MemberDecl = R.getAsSingle<FieldDecl>(); 6992 // FIXME: Leaks Res 6993 if (!MemberDecl) 6994 return ExprError(Diag(BuiltinLoc, diag::err_no_member) 6995 << OC.U.IdentInfo << RD << SourceRange(OC.LocStart, OC.LocEnd)); 6996 6997 // C99 7.17p3: 6998 // (If the specified member is a bit-field, the behavior is undefined.) 6999 // 7000 // We diagnose this as an error. 7001 if (MemberDecl->getBitWidth()) { 7002 Diag(OC.LocEnd, diag::err_offsetof_bitfield) 7003 << MemberDecl->getDeclName() 7004 << SourceRange(BuiltinLoc, RPLoc); 7005 Diag(MemberDecl->getLocation(), diag::note_bitfield_decl); 7006 return ExprError(); 7007 } 7008 7009 // FIXME: C++: Verify that MemberDecl isn't a static field. 7010 // FIXME: Verify that MemberDecl isn't a bitfield. 7011 if (cast<RecordDecl>(MemberDecl->getDeclContext())->isAnonymousStructOrUnion()) { 7012 Res = BuildAnonymousStructUnionMemberReference( 7013 OC.LocEnd, MemberDecl, Res, OC.LocEnd).takeAs<Expr>(); 7014 } else { 7015 PerformObjectMemberConversion(Res, /*Qualifier=*/0, 7016 *R.begin(), MemberDecl); 7017 // MemberDecl->getType() doesn't get the right qualifiers, but it 7018 // doesn't matter here. 7019 Res = new (Context) MemberExpr(Res, false, MemberDecl, OC.LocEnd, 7020 MemberDecl->getType().getNonReferenceType()); 7021 } 7022 } 7023 } 7024 7025 return Owned(new (Context) UnaryOperator(Res, UnaryOperator::OffsetOf, 7026 Context.getSizeType(), BuiltinLoc)); 7027} 7028 7029 7030Sema::OwningExprResult Sema::ActOnTypesCompatibleExpr(SourceLocation BuiltinLoc, 7031 TypeTy *arg1,TypeTy *arg2, 7032 SourceLocation RPLoc) { 7033 // FIXME: Preserve type source info. 7034 QualType argT1 = GetTypeFromParser(arg1); 7035 QualType argT2 = GetTypeFromParser(arg2); 7036 7037 assert((!argT1.isNull() && !argT2.isNull()) && "Missing type argument(s)"); 7038 7039 if (getLangOptions().CPlusPlus) { 7040 Diag(BuiltinLoc, diag::err_types_compatible_p_in_cplusplus) 7041 << SourceRange(BuiltinLoc, RPLoc); 7042 return ExprError(); 7043 } 7044 7045 return Owned(new (Context) TypesCompatibleExpr(Context.IntTy, BuiltinLoc, 7046 argT1, argT2, RPLoc)); 7047} 7048 7049Sema::OwningExprResult Sema::ActOnChooseExpr(SourceLocation BuiltinLoc, 7050 ExprArg cond, 7051 ExprArg expr1, ExprArg expr2, 7052 SourceLocation RPLoc) { 7053 Expr *CondExpr = static_cast<Expr*>(cond.get()); 7054 Expr *LHSExpr = static_cast<Expr*>(expr1.get()); 7055 Expr *RHSExpr = static_cast<Expr*>(expr2.get()); 7056 7057 assert((CondExpr && LHSExpr && RHSExpr) && "Missing type argument(s)"); 7058 7059 QualType resType; 7060 bool ValueDependent = false; 7061 if (CondExpr->isTypeDependent() || CondExpr->isValueDependent()) { 7062 resType = Context.DependentTy; 7063 ValueDependent = true; 7064 } else { 7065 // The conditional expression is required to be a constant expression. 7066 llvm::APSInt condEval(32); 7067 SourceLocation ExpLoc; 7068 if (!CondExpr->isIntegerConstantExpr(condEval, Context, &ExpLoc)) 7069 return ExprError(Diag(ExpLoc, 7070 diag::err_typecheck_choose_expr_requires_constant) 7071 << CondExpr->getSourceRange()); 7072 7073 // If the condition is > zero, then the AST type is the same as the LSHExpr. 7074 resType = condEval.getZExtValue() ? LHSExpr->getType() : RHSExpr->getType(); 7075 ValueDependent = condEval.getZExtValue() ? LHSExpr->isValueDependent() 7076 : RHSExpr->isValueDependent(); 7077 } 7078 7079 cond.release(); expr1.release(); expr2.release(); 7080 return Owned(new (Context) ChooseExpr(BuiltinLoc, CondExpr, LHSExpr, RHSExpr, 7081 resType, RPLoc, 7082 resType->isDependentType(), 7083 ValueDependent)); 7084} 7085 7086//===----------------------------------------------------------------------===// 7087// Clang Extensions. 7088//===----------------------------------------------------------------------===// 7089 7090/// ActOnBlockStart - This callback is invoked when a block literal is started. 7091void Sema::ActOnBlockStart(SourceLocation CaretLoc, Scope *BlockScope) { 7092 BlockDecl *Block = BlockDecl::Create(Context, CurContext, CaretLoc); 7093 PushBlockScope(BlockScope, Block); 7094 CurContext->addDecl(Block); 7095 if (BlockScope) 7096 PushDeclContext(BlockScope, Block); 7097 else 7098 CurContext = Block; 7099} 7100 7101void Sema::ActOnBlockArguments(Declarator &ParamInfo, Scope *CurScope) { 7102 assert(ParamInfo.getIdentifier()==0 && "block-id should have no identifier!"); 7103 BlockScopeInfo *CurBlock = getCurBlock(); 7104 7105 TypeSourceInfo *Sig = GetTypeForDeclarator(ParamInfo, CurScope); 7106 CurBlock->TheDecl->setSignatureAsWritten(Sig); 7107 QualType T = Sig->getType(); 7108 7109 bool isVariadic; 7110 QualType RetTy; 7111 if (const FunctionType *Fn = T->getAs<FunctionType>()) { 7112 CurBlock->FunctionType = T; 7113 RetTy = Fn->getResultType(); 7114 isVariadic = 7115 !isa<FunctionProtoType>(Fn) || cast<FunctionProtoType>(Fn)->isVariadic(); 7116 } else { 7117 RetTy = T; 7118 isVariadic = false; 7119 } 7120 7121 CurBlock->TheDecl->setIsVariadic(isVariadic); 7122 7123 // Don't allow returning an array by value. 7124 if (RetTy->isArrayType()) { 7125 Diag(ParamInfo.getSourceRange().getBegin(), diag::err_block_returns_array); 7126 return; 7127 } 7128 7129 // Don't allow returning a objc interface by value. 7130 if (RetTy->isObjCObjectType()) { 7131 Diag(ParamInfo.getSourceRange().getBegin(), 7132 diag::err_object_cannot_be_passed_returned_by_value) << 0 << RetTy; 7133 return; 7134 } 7135 7136 // Context.DependentTy is used as a placeholder for a missing block 7137 // return type. TODO: what should we do with declarators like: 7138 // ^ * { ... } 7139 // If the answer is "apply template argument deduction".... 7140 if (RetTy != Context.DependentTy) 7141 CurBlock->ReturnType = RetTy; 7142 7143 // Push block parameters from the declarator if we had them. 7144 llvm::SmallVector<ParmVarDecl*, 8> Params; 7145 if (isa<FunctionProtoType>(T)) { 7146 FunctionProtoTypeLoc TL = cast<FunctionProtoTypeLoc>(Sig->getTypeLoc()); 7147 for (unsigned I = 0, E = TL.getNumArgs(); I != E; ++I) { 7148 ParmVarDecl *Param = TL.getArg(I); 7149 if (Param->getIdentifier() == 0 && 7150 !Param->isImplicit() && 7151 !Param->isInvalidDecl() && 7152 !getLangOptions().CPlusPlus) 7153 Diag(Param->getLocation(), diag::err_parameter_name_omitted); 7154 Params.push_back(Param); 7155 } 7156 7157 // Fake up parameter variables if we have a typedef, like 7158 // ^ fntype { ... } 7159 } else if (const FunctionProtoType *Fn = T->getAs<FunctionProtoType>()) { 7160 for (FunctionProtoType::arg_type_iterator 7161 I = Fn->arg_type_begin(), E = Fn->arg_type_end(); I != E; ++I) { 7162 ParmVarDecl *Param = 7163 BuildParmVarDeclForTypedef(CurBlock->TheDecl, 7164 ParamInfo.getSourceRange().getBegin(), 7165 *I); 7166 Params.push_back(Param); 7167 } 7168 } 7169 7170 // Set the parameters on the block decl. 7171 if (!Params.empty()) 7172 CurBlock->TheDecl->setParams(Params.data(), Params.size()); 7173 7174 // Finally we can process decl attributes. 7175 ProcessDeclAttributes(CurScope, CurBlock->TheDecl, ParamInfo); 7176 7177 if (!isVariadic && CurBlock->TheDecl->getAttr<SentinelAttr>()) { 7178 Diag(ParamInfo.getAttributes()->getLoc(), 7179 diag::warn_attribute_sentinel_not_variadic) << 1; 7180 // FIXME: remove the attribute. 7181 } 7182 7183 // Put the parameter variables in scope. We can bail out immediately 7184 // if we don't have any. 7185 if (Params.empty()) 7186 return; 7187 7188 bool ShouldCheckShadow = 7189 Diags.getDiagnosticLevel(diag::warn_decl_shadow) != Diagnostic::Ignored; 7190 7191 for (BlockDecl::param_iterator AI = CurBlock->TheDecl->param_begin(), 7192 E = CurBlock->TheDecl->param_end(); AI != E; ++AI) { 7193 (*AI)->setOwningFunction(CurBlock->TheDecl); 7194 7195 // If this has an identifier, add it to the scope stack. 7196 if ((*AI)->getIdentifier()) { 7197 if (ShouldCheckShadow) 7198 CheckShadow(CurBlock->TheScope, *AI); 7199 7200 PushOnScopeChains(*AI, CurBlock->TheScope); 7201 } 7202 } 7203} 7204 7205/// ActOnBlockError - If there is an error parsing a block, this callback 7206/// is invoked to pop the information about the block from the action impl. 7207void Sema::ActOnBlockError(SourceLocation CaretLoc, Scope *CurScope) { 7208 // Pop off CurBlock, handle nested blocks. 7209 PopDeclContext(); 7210 PopFunctionOrBlockScope(); 7211 // FIXME: Delete the ParmVarDecl objects as well??? 7212} 7213 7214/// ActOnBlockStmtExpr - This is called when the body of a block statement 7215/// literal was successfully completed. ^(int x){...} 7216Sema::OwningExprResult Sema::ActOnBlockStmtExpr(SourceLocation CaretLoc, 7217 StmtArg body, Scope *CurScope) { 7218 // If blocks are disabled, emit an error. 7219 if (!LangOpts.Blocks) 7220 Diag(CaretLoc, diag::err_blocks_disable); 7221 7222 BlockScopeInfo *BSI = cast<BlockScopeInfo>(FunctionScopes.back()); 7223 7224 PopDeclContext(); 7225 7226 QualType RetTy = Context.VoidTy; 7227 if (!BSI->ReturnType.isNull()) 7228 RetTy = BSI->ReturnType; 7229 7230 bool NoReturn = BSI->TheDecl->getAttr<NoReturnAttr>(); 7231 QualType BlockTy; 7232 7233 // If the user wrote a function type in some form, try to use that. 7234 if (!BSI->FunctionType.isNull()) { 7235 const FunctionType *FTy = BSI->FunctionType->getAs<FunctionType>(); 7236 7237 FunctionType::ExtInfo Ext = FTy->getExtInfo(); 7238 if (NoReturn && !Ext.getNoReturn()) Ext = Ext.withNoReturn(true); 7239 7240 // Turn protoless block types into nullary block types. 7241 if (isa<FunctionNoProtoType>(FTy)) { 7242 BlockTy = Context.getFunctionType(RetTy, 0, 0, false, 0, 7243 false, false, 0, 0, Ext); 7244 7245 // Otherwise, if we don't need to change anything about the function type, 7246 // preserve its sugar structure. 7247 } else if (FTy->getResultType() == RetTy && 7248 (!NoReturn || FTy->getNoReturnAttr())) { 7249 BlockTy = BSI->FunctionType; 7250 7251 // Otherwise, make the minimal modifications to the function type. 7252 } else { 7253 const FunctionProtoType *FPT = cast<FunctionProtoType>(FTy); 7254 BlockTy = Context.getFunctionType(RetTy, 7255 FPT->arg_type_begin(), 7256 FPT->getNumArgs(), 7257 FPT->isVariadic(), 7258 /*quals*/ 0, 7259 FPT->hasExceptionSpec(), 7260 FPT->hasAnyExceptionSpec(), 7261 FPT->getNumExceptions(), 7262 FPT->exception_begin(), 7263 Ext); 7264 } 7265 7266 // If we don't have a function type, just build one from nothing. 7267 } else { 7268 BlockTy = Context.getFunctionType(RetTy, 0, 0, false, 0, 7269 false, false, 0, 0, 7270 FunctionType::ExtInfo(NoReturn, 0, CC_Default)); 7271 } 7272 7273 // FIXME: Check that return/parameter types are complete/non-abstract 7274 DiagnoseUnusedParameters(BSI->TheDecl->param_begin(), 7275 BSI->TheDecl->param_end()); 7276 BlockTy = Context.getBlockPointerType(BlockTy); 7277 7278 // If needed, diagnose invalid gotos and switches in the block. 7279 if (FunctionNeedsScopeChecking() && !hasAnyErrorsInThisFunction()) 7280 DiagnoseInvalidJumps(static_cast<CompoundStmt*>(body.get())); 7281 7282 BSI->TheDecl->setBody(body.takeAs<CompoundStmt>()); 7283 7284 bool Good = true; 7285 // Check goto/label use. 7286 for (llvm::DenseMap<IdentifierInfo*, LabelStmt*>::iterator 7287 I = BSI->LabelMap.begin(), E = BSI->LabelMap.end(); I != E; ++I) { 7288 LabelStmt *L = I->second; 7289 7290 // Verify that we have no forward references left. If so, there was a goto 7291 // or address of a label taken, but no definition of it. 7292 if (L->getSubStmt() != 0) 7293 continue; 7294 7295 // Emit error. 7296 Diag(L->getIdentLoc(), diag::err_undeclared_label_use) << L->getName(); 7297 Good = false; 7298 } 7299 if (!Good) { 7300 PopFunctionOrBlockScope(); 7301 return ExprError(); 7302 } 7303 7304 // Issue any analysis-based warnings. 7305 const sema::AnalysisBasedWarnings::Policy &WP = 7306 AnalysisWarnings.getDefaultPolicy(); 7307 AnalysisWarnings.IssueWarnings(WP, BSI->TheDecl, BlockTy); 7308 7309 Expr *Result = new (Context) BlockExpr(BSI->TheDecl, BlockTy, 7310 BSI->hasBlockDeclRefExprs); 7311 PopFunctionOrBlockScope(); 7312 return Owned(Result); 7313} 7314 7315Sema::OwningExprResult Sema::ActOnVAArg(SourceLocation BuiltinLoc, 7316 ExprArg expr, TypeTy *type, 7317 SourceLocation RPLoc) { 7318 QualType T = GetTypeFromParser(type); 7319 Expr *E = static_cast<Expr*>(expr.get()); 7320 Expr *OrigExpr = E; 7321 7322 InitBuiltinVaListType(); 7323 7324 // Get the va_list type 7325 QualType VaListType = Context.getBuiltinVaListType(); 7326 if (VaListType->isArrayType()) { 7327 // Deal with implicit array decay; for example, on x86-64, 7328 // va_list is an array, but it's supposed to decay to 7329 // a pointer for va_arg. 7330 VaListType = Context.getArrayDecayedType(VaListType); 7331 // Make sure the input expression also decays appropriately. 7332 UsualUnaryConversions(E); 7333 } else { 7334 // Otherwise, the va_list argument must be an l-value because 7335 // it is modified by va_arg. 7336 if (!E->isTypeDependent() && 7337 CheckForModifiableLvalue(E, BuiltinLoc, *this)) 7338 return ExprError(); 7339 } 7340 7341 if (!E->isTypeDependent() && 7342 !Context.hasSameType(VaListType, E->getType())) { 7343 return ExprError(Diag(E->getLocStart(), 7344 diag::err_first_argument_to_va_arg_not_of_type_va_list) 7345 << OrigExpr->getType() << E->getSourceRange()); 7346 } 7347 7348 // FIXME: Check that type is complete/non-abstract 7349 // FIXME: Warn if a non-POD type is passed in. 7350 7351 expr.release(); 7352 return Owned(new (Context) VAArgExpr(BuiltinLoc, E, T.getNonReferenceType(), 7353 RPLoc)); 7354} 7355 7356Sema::OwningExprResult Sema::ActOnGNUNullExpr(SourceLocation TokenLoc) { 7357 // The type of __null will be int or long, depending on the size of 7358 // pointers on the target. 7359 QualType Ty; 7360 if (Context.Target.getPointerWidth(0) == Context.Target.getIntWidth()) 7361 Ty = Context.IntTy; 7362 else 7363 Ty = Context.LongTy; 7364 7365 return Owned(new (Context) GNUNullExpr(Ty, TokenLoc)); 7366} 7367 7368static void MakeObjCStringLiteralFixItHint(Sema& SemaRef, QualType DstType, 7369 Expr *SrcExpr, FixItHint &Hint) { 7370 if (!SemaRef.getLangOptions().ObjC1) 7371 return; 7372 7373 const ObjCObjectPointerType *PT = DstType->getAs<ObjCObjectPointerType>(); 7374 if (!PT) 7375 return; 7376 7377 // Check if the destination is of type 'id'. 7378 if (!PT->isObjCIdType()) { 7379 // Check if the destination is the 'NSString' interface. 7380 const ObjCInterfaceDecl *ID = PT->getInterfaceDecl(); 7381 if (!ID || !ID->getIdentifier()->isStr("NSString")) 7382 return; 7383 } 7384 7385 // Strip off any parens and casts. 7386 StringLiteral *SL = dyn_cast<StringLiteral>(SrcExpr->IgnoreParenCasts()); 7387 if (!SL || SL->isWide()) 7388 return; 7389 7390 Hint = FixItHint::CreateInsertion(SL->getLocStart(), "@"); 7391} 7392 7393bool Sema::DiagnoseAssignmentResult(AssignConvertType ConvTy, 7394 SourceLocation Loc, 7395 QualType DstType, QualType SrcType, 7396 Expr *SrcExpr, AssignmentAction Action, 7397 bool *Complained) { 7398 if (Complained) 7399 *Complained = false; 7400 7401 // Decode the result (notice that AST's are still created for extensions). 7402 bool isInvalid = false; 7403 unsigned DiagKind; 7404 FixItHint Hint; 7405 7406 switch (ConvTy) { 7407 default: assert(0 && "Unknown conversion type"); 7408 case Compatible: return false; 7409 case PointerToInt: 7410 DiagKind = diag::ext_typecheck_convert_pointer_int; 7411 break; 7412 case IntToPointer: 7413 DiagKind = diag::ext_typecheck_convert_int_pointer; 7414 break; 7415 case IncompatiblePointer: 7416 MakeObjCStringLiteralFixItHint(*this, DstType, SrcExpr, Hint); 7417 DiagKind = diag::ext_typecheck_convert_incompatible_pointer; 7418 break; 7419 case IncompatiblePointerSign: 7420 DiagKind = diag::ext_typecheck_convert_incompatible_pointer_sign; 7421 break; 7422 case FunctionVoidPointer: 7423 DiagKind = diag::ext_typecheck_convert_pointer_void_func; 7424 break; 7425 case CompatiblePointerDiscardsQualifiers: 7426 // If the qualifiers lost were because we were applying the 7427 // (deprecated) C++ conversion from a string literal to a char* 7428 // (or wchar_t*), then there was no error (C++ 4.2p2). FIXME: 7429 // Ideally, this check would be performed in 7430 // CheckPointerTypesForAssignment. However, that would require a 7431 // bit of refactoring (so that the second argument is an 7432 // expression, rather than a type), which should be done as part 7433 // of a larger effort to fix CheckPointerTypesForAssignment for 7434 // C++ semantics. 7435 if (getLangOptions().CPlusPlus && 7436 IsStringLiteralToNonConstPointerConversion(SrcExpr, DstType)) 7437 return false; 7438 DiagKind = diag::ext_typecheck_convert_discards_qualifiers; 7439 break; 7440 case IncompatibleNestedPointerQualifiers: 7441 DiagKind = diag::ext_nested_pointer_qualifier_mismatch; 7442 break; 7443 case IntToBlockPointer: 7444 DiagKind = diag::err_int_to_block_pointer; 7445 break; 7446 case IncompatibleBlockPointer: 7447 DiagKind = diag::err_typecheck_convert_incompatible_block_pointer; 7448 break; 7449 case IncompatibleObjCQualifiedId: 7450 // FIXME: Diagnose the problem in ObjCQualifiedIdTypesAreCompatible, since 7451 // it can give a more specific diagnostic. 7452 DiagKind = diag::warn_incompatible_qualified_id; 7453 break; 7454 case IncompatibleVectors: 7455 DiagKind = diag::warn_incompatible_vectors; 7456 break; 7457 case Incompatible: 7458 DiagKind = diag::err_typecheck_convert_incompatible; 7459 isInvalid = true; 7460 break; 7461 } 7462 7463 QualType FirstType, SecondType; 7464 switch (Action) { 7465 case AA_Assigning: 7466 case AA_Initializing: 7467 // The destination type comes first. 7468 FirstType = DstType; 7469 SecondType = SrcType; 7470 break; 7471 7472 case AA_Returning: 7473 case AA_Passing: 7474 case AA_Converting: 7475 case AA_Sending: 7476 case AA_Casting: 7477 // The source type comes first. 7478 FirstType = SrcType; 7479 SecondType = DstType; 7480 break; 7481 } 7482 7483 Diag(Loc, DiagKind) << FirstType << SecondType << Action 7484 << SrcExpr->getSourceRange() << Hint; 7485 if (Complained) 7486 *Complained = true; 7487 return isInvalid; 7488} 7489 7490bool Sema::VerifyIntegerConstantExpression(const Expr *E, llvm::APSInt *Result){ 7491 llvm::APSInt ICEResult; 7492 if (E->isIntegerConstantExpr(ICEResult, Context)) { 7493 if (Result) 7494 *Result = ICEResult; 7495 return false; 7496 } 7497 7498 Expr::EvalResult EvalResult; 7499 7500 if (!E->Evaluate(EvalResult, Context) || !EvalResult.Val.isInt() || 7501 EvalResult.HasSideEffects) { 7502 Diag(E->getExprLoc(), diag::err_expr_not_ice) << E->getSourceRange(); 7503 7504 if (EvalResult.Diag) { 7505 // We only show the note if it's not the usual "invalid subexpression" 7506 // or if it's actually in a subexpression. 7507 if (EvalResult.Diag != diag::note_invalid_subexpr_in_ice || 7508 E->IgnoreParens() != EvalResult.DiagExpr->IgnoreParens()) 7509 Diag(EvalResult.DiagLoc, EvalResult.Diag); 7510 } 7511 7512 return true; 7513 } 7514 7515 Diag(E->getExprLoc(), diag::ext_expr_not_ice) << 7516 E->getSourceRange(); 7517 7518 if (EvalResult.Diag && 7519 Diags.getDiagnosticLevel(diag::ext_expr_not_ice) != Diagnostic::Ignored) 7520 Diag(EvalResult.DiagLoc, EvalResult.Diag); 7521 7522 if (Result) 7523 *Result = EvalResult.Val.getInt(); 7524 return false; 7525} 7526 7527void 7528Sema::PushExpressionEvaluationContext(ExpressionEvaluationContext NewContext) { 7529 ExprEvalContexts.push_back( 7530 ExpressionEvaluationContextRecord(NewContext, ExprTemporaries.size())); 7531} 7532 7533void 7534Sema::PopExpressionEvaluationContext() { 7535 // Pop the current expression evaluation context off the stack. 7536 ExpressionEvaluationContextRecord Rec = ExprEvalContexts.back(); 7537 ExprEvalContexts.pop_back(); 7538 7539 if (Rec.Context == PotentiallyPotentiallyEvaluated) { 7540 if (Rec.PotentiallyReferenced) { 7541 // Mark any remaining declarations in the current position of the stack 7542 // as "referenced". If they were not meant to be referenced, semantic 7543 // analysis would have eliminated them (e.g., in ActOnCXXTypeId). 7544 for (PotentiallyReferencedDecls::iterator 7545 I = Rec.PotentiallyReferenced->begin(), 7546 IEnd = Rec.PotentiallyReferenced->end(); 7547 I != IEnd; ++I) 7548 MarkDeclarationReferenced(I->first, I->second); 7549 } 7550 7551 if (Rec.PotentiallyDiagnosed) { 7552 // Emit any pending diagnostics. 7553 for (PotentiallyEmittedDiagnostics::iterator 7554 I = Rec.PotentiallyDiagnosed->begin(), 7555 IEnd = Rec.PotentiallyDiagnosed->end(); 7556 I != IEnd; ++I) 7557 Diag(I->first, I->second); 7558 } 7559 } 7560 7561 // When are coming out of an unevaluated context, clear out any 7562 // temporaries that we may have created as part of the evaluation of 7563 // the expression in that context: they aren't relevant because they 7564 // will never be constructed. 7565 if (Rec.Context == Unevaluated && 7566 ExprTemporaries.size() > Rec.NumTemporaries) 7567 ExprTemporaries.erase(ExprTemporaries.begin() + Rec.NumTemporaries, 7568 ExprTemporaries.end()); 7569 7570 // Destroy the popped expression evaluation record. 7571 Rec.Destroy(); 7572} 7573 7574/// \brief Note that the given declaration was referenced in the source code. 7575/// 7576/// This routine should be invoke whenever a given declaration is referenced 7577/// in the source code, and where that reference occurred. If this declaration 7578/// reference means that the the declaration is used (C++ [basic.def.odr]p2, 7579/// C99 6.9p3), then the declaration will be marked as used. 7580/// 7581/// \param Loc the location where the declaration was referenced. 7582/// 7583/// \param D the declaration that has been referenced by the source code. 7584void Sema::MarkDeclarationReferenced(SourceLocation Loc, Decl *D) { 7585 assert(D && "No declaration?"); 7586 7587 if (D->isUsed(false)) 7588 return; 7589 7590 // Mark a parameter or variable declaration "used", regardless of whether we're in a 7591 // template or not. The reason for this is that unevaluated expressions 7592 // (e.g. (void)sizeof()) constitute a use for warning purposes (-Wunused-variables and 7593 // -Wunused-parameters) 7594 if (isa<ParmVarDecl>(D) || 7595 (isa<VarDecl>(D) && D->getDeclContext()->isFunctionOrMethod())) { 7596 D->setUsed(true); 7597 return; 7598 } 7599 7600 if (!isa<VarDecl>(D) && !isa<FunctionDecl>(D)) 7601 return; 7602 7603 // Do not mark anything as "used" within a dependent context; wait for 7604 // an instantiation. 7605 if (CurContext->isDependentContext()) 7606 return; 7607 7608 switch (ExprEvalContexts.back().Context) { 7609 case Unevaluated: 7610 // We are in an expression that is not potentially evaluated; do nothing. 7611 return; 7612 7613 case PotentiallyEvaluated: 7614 // We are in a potentially-evaluated expression, so this declaration is 7615 // "used"; handle this below. 7616 break; 7617 7618 case PotentiallyPotentiallyEvaluated: 7619 // We are in an expression that may be potentially evaluated; queue this 7620 // declaration reference until we know whether the expression is 7621 // potentially evaluated. 7622 ExprEvalContexts.back().addReferencedDecl(Loc, D); 7623 return; 7624 } 7625 7626 // Note that this declaration has been used. 7627 if (CXXConstructorDecl *Constructor = dyn_cast<CXXConstructorDecl>(D)) { 7628 unsigned TypeQuals; 7629 if (Constructor->isImplicit() && Constructor->isDefaultConstructor()) { 7630 if (!Constructor->isUsed(false)) 7631 DefineImplicitDefaultConstructor(Loc, Constructor); 7632 } else if (Constructor->isImplicit() && 7633 Constructor->isCopyConstructor(TypeQuals)) { 7634 if (!Constructor->isUsed(false)) 7635 DefineImplicitCopyConstructor(Loc, Constructor, TypeQuals); 7636 } 7637 7638 MarkVTableUsed(Loc, Constructor->getParent()); 7639 } else if (CXXDestructorDecl *Destructor = dyn_cast<CXXDestructorDecl>(D)) { 7640 if (Destructor->isImplicit() && !Destructor->isUsed(false)) 7641 DefineImplicitDestructor(Loc, Destructor); 7642 if (Destructor->isVirtual()) 7643 MarkVTableUsed(Loc, Destructor->getParent()); 7644 } else if (CXXMethodDecl *MethodDecl = dyn_cast<CXXMethodDecl>(D)) { 7645 if (MethodDecl->isImplicit() && MethodDecl->isOverloadedOperator() && 7646 MethodDecl->getOverloadedOperator() == OO_Equal) { 7647 if (!MethodDecl->isUsed(false)) 7648 DefineImplicitCopyAssignment(Loc, MethodDecl); 7649 } else if (MethodDecl->isVirtual()) 7650 MarkVTableUsed(Loc, MethodDecl->getParent()); 7651 } 7652 if (FunctionDecl *Function = dyn_cast<FunctionDecl>(D)) { 7653 // Implicit instantiation of function templates and member functions of 7654 // class templates. 7655 if (Function->isImplicitlyInstantiable()) { 7656 bool AlreadyInstantiated = false; 7657 if (FunctionTemplateSpecializationInfo *SpecInfo 7658 = Function->getTemplateSpecializationInfo()) { 7659 if (SpecInfo->getPointOfInstantiation().isInvalid()) 7660 SpecInfo->setPointOfInstantiation(Loc); 7661 else if (SpecInfo->getTemplateSpecializationKind() 7662 == TSK_ImplicitInstantiation) 7663 AlreadyInstantiated = true; 7664 } else if (MemberSpecializationInfo *MSInfo 7665 = Function->getMemberSpecializationInfo()) { 7666 if (MSInfo->getPointOfInstantiation().isInvalid()) 7667 MSInfo->setPointOfInstantiation(Loc); 7668 else if (MSInfo->getTemplateSpecializationKind() 7669 == TSK_ImplicitInstantiation) 7670 AlreadyInstantiated = true; 7671 } 7672 7673 if (!AlreadyInstantiated) { 7674 if (isa<CXXRecordDecl>(Function->getDeclContext()) && 7675 cast<CXXRecordDecl>(Function->getDeclContext())->isLocalClass()) 7676 PendingLocalImplicitInstantiations.push_back(std::make_pair(Function, 7677 Loc)); 7678 else 7679 PendingImplicitInstantiations.push_back(std::make_pair(Function, 7680 Loc)); 7681 } 7682 } 7683 7684 // FIXME: keep track of references to static functions 7685 Function->setUsed(true); 7686 7687 return; 7688 } 7689 7690 if (VarDecl *Var = dyn_cast<VarDecl>(D)) { 7691 // Implicit instantiation of static data members of class templates. 7692 if (Var->isStaticDataMember() && 7693 Var->getInstantiatedFromStaticDataMember()) { 7694 MemberSpecializationInfo *MSInfo = Var->getMemberSpecializationInfo(); 7695 assert(MSInfo && "Missing member specialization information?"); 7696 if (MSInfo->getPointOfInstantiation().isInvalid() && 7697 MSInfo->getTemplateSpecializationKind()== TSK_ImplicitInstantiation) { 7698 MSInfo->setPointOfInstantiation(Loc); 7699 PendingImplicitInstantiations.push_back(std::make_pair(Var, Loc)); 7700 } 7701 } 7702 7703 // FIXME: keep track of references to static data? 7704 7705 D->setUsed(true); 7706 return; 7707 } 7708} 7709 7710namespace { 7711 // Mark all of the declarations referenced 7712 // FIXME: Not fully implemented yet! We need to have a better understanding 7713 // of when we're entering 7714 class MarkReferencedDecls : public RecursiveASTVisitor<MarkReferencedDecls> { 7715 Sema &S; 7716 SourceLocation Loc; 7717 7718 public: 7719 typedef RecursiveASTVisitor<MarkReferencedDecls> Inherited; 7720 7721 MarkReferencedDecls(Sema &S, SourceLocation Loc) : S(S), Loc(Loc) { } 7722 7723 bool TraverseTemplateArgument(const TemplateArgument &Arg); 7724 bool TraverseRecordType(RecordType *T); 7725 }; 7726} 7727 7728bool MarkReferencedDecls::TraverseTemplateArgument( 7729 const TemplateArgument &Arg) { 7730 if (Arg.getKind() == TemplateArgument::Declaration) { 7731 S.MarkDeclarationReferenced(Loc, Arg.getAsDecl()); 7732 } 7733 7734 return Inherited::TraverseTemplateArgument(Arg); 7735} 7736 7737bool MarkReferencedDecls::TraverseRecordType(RecordType *T) { 7738 if (ClassTemplateSpecializationDecl *Spec 7739 = dyn_cast<ClassTemplateSpecializationDecl>(T->getDecl())) { 7740 const TemplateArgumentList &Args = Spec->getTemplateArgs(); 7741 return TraverseTemplateArguments(Args.getFlatArgumentList(), 7742 Args.flat_size()); 7743 } 7744 7745 return true; 7746} 7747 7748void Sema::MarkDeclarationsReferencedInType(SourceLocation Loc, QualType T) { 7749 MarkReferencedDecls Marker(*this, Loc); 7750 Marker.TraverseType(Context.getCanonicalType(T)); 7751} 7752 7753/// \brief Emit a diagnostic that describes an effect on the run-time behavior 7754/// of the program being compiled. 7755/// 7756/// This routine emits the given diagnostic when the code currently being 7757/// type-checked is "potentially evaluated", meaning that there is a 7758/// possibility that the code will actually be executable. Code in sizeof() 7759/// expressions, code used only during overload resolution, etc., are not 7760/// potentially evaluated. This routine will suppress such diagnostics or, 7761/// in the absolutely nutty case of potentially potentially evaluated 7762/// expressions (C++ typeid), queue the diagnostic to potentially emit it 7763/// later. 7764/// 7765/// This routine should be used for all diagnostics that describe the run-time 7766/// behavior of a program, such as passing a non-POD value through an ellipsis. 7767/// Failure to do so will likely result in spurious diagnostics or failures 7768/// during overload resolution or within sizeof/alignof/typeof/typeid. 7769bool Sema::DiagRuntimeBehavior(SourceLocation Loc, 7770 const PartialDiagnostic &PD) { 7771 switch (ExprEvalContexts.back().Context ) { 7772 case Unevaluated: 7773 // The argument will never be evaluated, so don't complain. 7774 break; 7775 7776 case PotentiallyEvaluated: 7777 Diag(Loc, PD); 7778 return true; 7779 7780 case PotentiallyPotentiallyEvaluated: 7781 ExprEvalContexts.back().addDiagnostic(Loc, PD); 7782 break; 7783 } 7784 7785 return false; 7786} 7787 7788bool Sema::CheckCallReturnType(QualType ReturnType, SourceLocation Loc, 7789 CallExpr *CE, FunctionDecl *FD) { 7790 if (ReturnType->isVoidType() || !ReturnType->isIncompleteType()) 7791 return false; 7792 7793 PartialDiagnostic Note = 7794 FD ? PDiag(diag::note_function_with_incomplete_return_type_declared_here) 7795 << FD->getDeclName() : PDiag(); 7796 SourceLocation NoteLoc = FD ? FD->getLocation() : SourceLocation(); 7797 7798 if (RequireCompleteType(Loc, ReturnType, 7799 FD ? 7800 PDiag(diag::err_call_function_incomplete_return) 7801 << CE->getSourceRange() << FD->getDeclName() : 7802 PDiag(diag::err_call_incomplete_return) 7803 << CE->getSourceRange(), 7804 std::make_pair(NoteLoc, Note))) 7805 return true; 7806 7807 return false; 7808} 7809 7810// Diagnose the common s/=/==/ typo. Note that adding parentheses 7811// will prevent this condition from triggering, which is what we want. 7812void Sema::DiagnoseAssignmentAsCondition(Expr *E) { 7813 SourceLocation Loc; 7814 7815 unsigned diagnostic = diag::warn_condition_is_assignment; 7816 7817 if (isa<BinaryOperator>(E)) { 7818 BinaryOperator *Op = cast<BinaryOperator>(E); 7819 if (Op->getOpcode() != BinaryOperator::Assign) 7820 return; 7821 7822 // Greylist some idioms by putting them into a warning subcategory. 7823 if (ObjCMessageExpr *ME 7824 = dyn_cast<ObjCMessageExpr>(Op->getRHS()->IgnoreParenCasts())) { 7825 Selector Sel = ME->getSelector(); 7826 7827 // self = [<foo> init...] 7828 if (isSelfExpr(Op->getLHS()) 7829 && Sel.getIdentifierInfoForSlot(0)->getName().startswith("init")) 7830 diagnostic = diag::warn_condition_is_idiomatic_assignment; 7831 7832 // <foo> = [<bar> nextObject] 7833 else if (Sel.isUnarySelector() && 7834 Sel.getIdentifierInfoForSlot(0)->getName() == "nextObject") 7835 diagnostic = diag::warn_condition_is_idiomatic_assignment; 7836 } 7837 7838 Loc = Op->getOperatorLoc(); 7839 } else if (isa<CXXOperatorCallExpr>(E)) { 7840 CXXOperatorCallExpr *Op = cast<CXXOperatorCallExpr>(E); 7841 if (Op->getOperator() != OO_Equal) 7842 return; 7843 7844 Loc = Op->getOperatorLoc(); 7845 } else { 7846 // Not an assignment. 7847 return; 7848 } 7849 7850 SourceLocation Open = E->getSourceRange().getBegin(); 7851 SourceLocation Close = PP.getLocForEndOfToken(E->getSourceRange().getEnd()); 7852 7853 Diag(Loc, diagnostic) << E->getSourceRange(); 7854 Diag(Loc, diag::note_condition_assign_to_comparison) 7855 << FixItHint::CreateReplacement(Loc, "=="); 7856 Diag(Loc, diag::note_condition_assign_silence) 7857 << FixItHint::CreateInsertion(Open, "(") 7858 << FixItHint::CreateInsertion(Close, ")"); 7859} 7860 7861bool Sema::CheckBooleanCondition(Expr *&E, SourceLocation Loc) { 7862 DiagnoseAssignmentAsCondition(E); 7863 7864 if (!E->isTypeDependent()) { 7865 DefaultFunctionArrayLvalueConversion(E); 7866 7867 QualType T = E->getType(); 7868 7869 if (getLangOptions().CPlusPlus) { 7870 if (CheckCXXBooleanCondition(E)) // C++ 6.4p4 7871 return true; 7872 } else if (!T->isScalarType()) { // C99 6.8.4.1p1 7873 Diag(Loc, diag::err_typecheck_statement_requires_scalar) 7874 << T << E->getSourceRange(); 7875 return true; 7876 } 7877 } 7878 7879 return false; 7880} 7881 7882Sema::OwningExprResult Sema::ActOnBooleanCondition(Scope *S, SourceLocation Loc, 7883 ExprArg SubExpr) { 7884 Expr *Sub = SubExpr.takeAs<Expr>(); 7885 if (!Sub) 7886 return ExprError(); 7887 7888 if (CheckBooleanCondition(Sub, Loc)) { 7889 Sub->Destroy(Context); 7890 return ExprError(); 7891 } 7892 7893 return Owned(Sub); 7894} 7895