SemaExpr.cpp revision a729da2c29e7df26319acf2675d51e377287a139
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 && !T->isDependentType() && 1752 !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 return Owned(BDRE); 1769 } 1770 // If this reference is not in a block or if the referenced variable is 1771 // within the block, create a normal DeclRefExpr. 1772 1773 return BuildDeclRefExpr(VD, VD->getType().getNonReferenceType(), Loc, &SS); 1774} 1775 1776Sema::OwningExprResult Sema::ActOnPredefinedExpr(SourceLocation Loc, 1777 tok::TokenKind Kind) { 1778 PredefinedExpr::IdentType IT; 1779 1780 switch (Kind) { 1781 default: assert(0 && "Unknown simple primary expr!"); 1782 case tok::kw___func__: IT = PredefinedExpr::Func; break; // [C99 6.4.2.2] 1783 case tok::kw___FUNCTION__: IT = PredefinedExpr::Function; break; 1784 case tok::kw___PRETTY_FUNCTION__: IT = PredefinedExpr::PrettyFunction; break; 1785 } 1786 1787 // Pre-defined identifiers are of type char[x], where x is the length of the 1788 // string. 1789 1790 Decl *currentDecl = getCurFunctionOrMethodDecl(); 1791 if (!currentDecl) { 1792 Diag(Loc, diag::ext_predef_outside_function); 1793 currentDecl = Context.getTranslationUnitDecl(); 1794 } 1795 1796 QualType ResTy; 1797 if (cast<DeclContext>(currentDecl)->isDependentContext()) { 1798 ResTy = Context.DependentTy; 1799 } else { 1800 unsigned Length = PredefinedExpr::ComputeName(IT, currentDecl).length(); 1801 1802 llvm::APInt LengthI(32, Length + 1); 1803 ResTy = Context.CharTy.withConst(); 1804 ResTy = Context.getConstantArrayType(ResTy, LengthI, ArrayType::Normal, 0); 1805 } 1806 return Owned(new (Context) PredefinedExpr(Loc, ResTy, IT)); 1807} 1808 1809Sema::OwningExprResult Sema::ActOnCharacterConstant(const Token &Tok) { 1810 llvm::SmallString<16> CharBuffer; 1811 bool Invalid = false; 1812 llvm::StringRef ThisTok = PP.getSpelling(Tok, CharBuffer, &Invalid); 1813 if (Invalid) 1814 return ExprError(); 1815 1816 CharLiteralParser Literal(ThisTok.begin(), ThisTok.end(), Tok.getLocation(), 1817 PP); 1818 if (Literal.hadError()) 1819 return ExprError(); 1820 1821 QualType Ty; 1822 if (!getLangOptions().CPlusPlus) 1823 Ty = Context.IntTy; // 'x' and L'x' -> int in C. 1824 else if (Literal.isWide()) 1825 Ty = Context.WCharTy; // L'x' -> wchar_t in C++. 1826 else if (Literal.isMultiChar()) 1827 Ty = Context.IntTy; // 'wxyz' -> int in C++. 1828 else 1829 Ty = Context.CharTy; // 'x' -> char in C++ 1830 1831 return Owned(new (Context) CharacterLiteral(Literal.getValue(), 1832 Literal.isWide(), 1833 Ty, Tok.getLocation())); 1834} 1835 1836Action::OwningExprResult Sema::ActOnNumericConstant(const Token &Tok) { 1837 // Fast path for a single digit (which is quite common). A single digit 1838 // cannot have a trigraph, escaped newline, radix prefix, or type suffix. 1839 if (Tok.getLength() == 1) { 1840 const char Val = PP.getSpellingOfSingleCharacterNumericConstant(Tok); 1841 unsigned IntSize = Context.Target.getIntWidth(); 1842 return Owned(new (Context) IntegerLiteral(llvm::APInt(IntSize, Val-'0'), 1843 Context.IntTy, Tok.getLocation())); 1844 } 1845 1846 llvm::SmallString<512> IntegerBuffer; 1847 // Add padding so that NumericLiteralParser can overread by one character. 1848 IntegerBuffer.resize(Tok.getLength()+1); 1849 const char *ThisTokBegin = &IntegerBuffer[0]; 1850 1851 // Get the spelling of the token, which eliminates trigraphs, etc. 1852 bool Invalid = false; 1853 unsigned ActualLength = PP.getSpelling(Tok, ThisTokBegin, &Invalid); 1854 if (Invalid) 1855 return ExprError(); 1856 1857 NumericLiteralParser Literal(ThisTokBegin, ThisTokBegin+ActualLength, 1858 Tok.getLocation(), PP); 1859 if (Literal.hadError) 1860 return ExprError(); 1861 1862 Expr *Res; 1863 1864 if (Literal.isFloatingLiteral()) { 1865 QualType Ty; 1866 if (Literal.isFloat) 1867 Ty = Context.FloatTy; 1868 else if (!Literal.isLong) 1869 Ty = Context.DoubleTy; 1870 else 1871 Ty = Context.LongDoubleTy; 1872 1873 const llvm::fltSemantics &Format = Context.getFloatTypeSemantics(Ty); 1874 1875 using llvm::APFloat; 1876 APFloat Val(Format); 1877 1878 APFloat::opStatus result = Literal.GetFloatValue(Val); 1879 1880 // Overflow is always an error, but underflow is only an error if 1881 // we underflowed to zero (APFloat reports denormals as underflow). 1882 if ((result & APFloat::opOverflow) || 1883 ((result & APFloat::opUnderflow) && Val.isZero())) { 1884 unsigned diagnostic; 1885 llvm::SmallString<20> buffer; 1886 if (result & APFloat::opOverflow) { 1887 diagnostic = diag::warn_float_overflow; 1888 APFloat::getLargest(Format).toString(buffer); 1889 } else { 1890 diagnostic = diag::warn_float_underflow; 1891 APFloat::getSmallest(Format).toString(buffer); 1892 } 1893 1894 Diag(Tok.getLocation(), diagnostic) 1895 << Ty 1896 << llvm::StringRef(buffer.data(), buffer.size()); 1897 } 1898 1899 bool isExact = (result == APFloat::opOK); 1900 Res = new (Context) FloatingLiteral(Val, isExact, Ty, Tok.getLocation()); 1901 1902 } else if (!Literal.isIntegerLiteral()) { 1903 return ExprError(); 1904 } else { 1905 QualType Ty; 1906 1907 // long long is a C99 feature. 1908 if (!getLangOptions().C99 && !getLangOptions().CPlusPlus0x && 1909 Literal.isLongLong) 1910 Diag(Tok.getLocation(), diag::ext_longlong); 1911 1912 // Get the value in the widest-possible width. 1913 llvm::APInt ResultVal(Context.Target.getIntMaxTWidth(), 0); 1914 1915 if (Literal.GetIntegerValue(ResultVal)) { 1916 // If this value didn't fit into uintmax_t, warn and force to ull. 1917 Diag(Tok.getLocation(), diag::warn_integer_too_large); 1918 Ty = Context.UnsignedLongLongTy; 1919 assert(Context.getTypeSize(Ty) == ResultVal.getBitWidth() && 1920 "long long is not intmax_t?"); 1921 } else { 1922 // If this value fits into a ULL, try to figure out what else it fits into 1923 // according to the rules of C99 6.4.4.1p5. 1924 1925 // Octal, Hexadecimal, and integers with a U suffix are allowed to 1926 // be an unsigned int. 1927 bool AllowUnsigned = Literal.isUnsigned || Literal.getRadix() != 10; 1928 1929 // Check from smallest to largest, picking the smallest type we can. 1930 unsigned Width = 0; 1931 if (!Literal.isLong && !Literal.isLongLong) { 1932 // Are int/unsigned possibilities? 1933 unsigned IntSize = Context.Target.getIntWidth(); 1934 1935 // Does it fit in a unsigned int? 1936 if (ResultVal.isIntN(IntSize)) { 1937 // Does it fit in a signed int? 1938 if (!Literal.isUnsigned && ResultVal[IntSize-1] == 0) 1939 Ty = Context.IntTy; 1940 else if (AllowUnsigned) 1941 Ty = Context.UnsignedIntTy; 1942 Width = IntSize; 1943 } 1944 } 1945 1946 // Are long/unsigned long possibilities? 1947 if (Ty.isNull() && !Literal.isLongLong) { 1948 unsigned LongSize = Context.Target.getLongWidth(); 1949 1950 // Does it fit in a unsigned long? 1951 if (ResultVal.isIntN(LongSize)) { 1952 // Does it fit in a signed long? 1953 if (!Literal.isUnsigned && ResultVal[LongSize-1] == 0) 1954 Ty = Context.LongTy; 1955 else if (AllowUnsigned) 1956 Ty = Context.UnsignedLongTy; 1957 Width = LongSize; 1958 } 1959 } 1960 1961 // Finally, check long long if needed. 1962 if (Ty.isNull()) { 1963 unsigned LongLongSize = Context.Target.getLongLongWidth(); 1964 1965 // Does it fit in a unsigned long long? 1966 if (ResultVal.isIntN(LongLongSize)) { 1967 // Does it fit in a signed long long? 1968 if (!Literal.isUnsigned && ResultVal[LongLongSize-1] == 0) 1969 Ty = Context.LongLongTy; 1970 else if (AllowUnsigned) 1971 Ty = Context.UnsignedLongLongTy; 1972 Width = LongLongSize; 1973 } 1974 } 1975 1976 // If we still couldn't decide a type, we probably have something that 1977 // does not fit in a signed long long, but has no U suffix. 1978 if (Ty.isNull()) { 1979 Diag(Tok.getLocation(), diag::warn_integer_too_large_for_signed); 1980 Ty = Context.UnsignedLongLongTy; 1981 Width = Context.Target.getLongLongWidth(); 1982 } 1983 1984 if (ResultVal.getBitWidth() != Width) 1985 ResultVal.trunc(Width); 1986 } 1987 Res = new (Context) IntegerLiteral(ResultVal, Ty, Tok.getLocation()); 1988 } 1989 1990 // If this is an imaginary literal, create the ImaginaryLiteral wrapper. 1991 if (Literal.isImaginary) 1992 Res = new (Context) ImaginaryLiteral(Res, 1993 Context.getComplexType(Res->getType())); 1994 1995 return Owned(Res); 1996} 1997 1998Action::OwningExprResult Sema::ActOnParenExpr(SourceLocation L, 1999 SourceLocation R, ExprArg Val) { 2000 Expr *E = Val.takeAs<Expr>(); 2001 assert((E != 0) && "ActOnParenExpr() missing expr"); 2002 return Owned(new (Context) ParenExpr(L, R, E)); 2003} 2004 2005/// The UsualUnaryConversions() function is *not* called by this routine. 2006/// See C99 6.3.2.1p[2-4] for more details. 2007bool Sema::CheckSizeOfAlignOfOperand(QualType exprType, 2008 SourceLocation OpLoc, 2009 const SourceRange &ExprRange, 2010 bool isSizeof) { 2011 if (exprType->isDependentType()) 2012 return false; 2013 2014 // C++ [expr.sizeof]p2: "When applied to a reference or a reference type, 2015 // the result is the size of the referenced type." 2016 // C++ [expr.alignof]p3: "When alignof is applied to a reference type, the 2017 // result shall be the alignment of the referenced type." 2018 if (const ReferenceType *Ref = exprType->getAs<ReferenceType>()) 2019 exprType = Ref->getPointeeType(); 2020 2021 // C99 6.5.3.4p1: 2022 if (exprType->isFunctionType()) { 2023 // alignof(function) is allowed as an extension. 2024 if (isSizeof) 2025 Diag(OpLoc, diag::ext_sizeof_function_type) << ExprRange; 2026 return false; 2027 } 2028 2029 // Allow sizeof(void)/alignof(void) as an extension. 2030 if (exprType->isVoidType()) { 2031 Diag(OpLoc, diag::ext_sizeof_void_type) 2032 << (isSizeof ? "sizeof" : "__alignof") << ExprRange; 2033 return false; 2034 } 2035 2036 if (RequireCompleteType(OpLoc, exprType, 2037 PDiag(diag::err_sizeof_alignof_incomplete_type) 2038 << int(!isSizeof) << ExprRange)) 2039 return true; 2040 2041 // Reject sizeof(interface) and sizeof(interface<proto>) in 64-bit mode. 2042 if (LangOpts.ObjCNonFragileABI && exprType->isObjCObjectType()) { 2043 Diag(OpLoc, diag::err_sizeof_nonfragile_interface) 2044 << exprType << isSizeof << ExprRange; 2045 return true; 2046 } 2047 2048 if (Context.hasSameUnqualifiedType(exprType, Context.OverloadTy)) { 2049 Diag(OpLoc, diag::err_sizeof_alignof_overloaded_function_type) 2050 << !isSizeof << ExprRange; 2051 return true; 2052 } 2053 2054 return false; 2055} 2056 2057bool Sema::CheckAlignOfExpr(Expr *E, SourceLocation OpLoc, 2058 const SourceRange &ExprRange) { 2059 E = E->IgnoreParens(); 2060 2061 // alignof decl is always ok. 2062 if (isa<DeclRefExpr>(E)) 2063 return false; 2064 2065 // Cannot know anything else if the expression is dependent. 2066 if (E->isTypeDependent()) 2067 return false; 2068 2069 if (E->getBitField()) { 2070 Diag(OpLoc, diag::err_sizeof_alignof_bitfield) << 1 << ExprRange; 2071 return true; 2072 } 2073 2074 // Alignment of a field access is always okay, so long as it isn't a 2075 // bit-field. 2076 if (MemberExpr *ME = dyn_cast<MemberExpr>(E)) 2077 if (isa<FieldDecl>(ME->getMemberDecl())) 2078 return false; 2079 2080 return CheckSizeOfAlignOfOperand(E->getType(), OpLoc, ExprRange, false); 2081} 2082 2083/// \brief Build a sizeof or alignof expression given a type operand. 2084Action::OwningExprResult 2085Sema::CreateSizeOfAlignOfExpr(TypeSourceInfo *TInfo, 2086 SourceLocation OpLoc, 2087 bool isSizeOf, SourceRange R) { 2088 if (!TInfo) 2089 return ExprError(); 2090 2091 QualType T = TInfo->getType(); 2092 2093 if (!T->isDependentType() && 2094 CheckSizeOfAlignOfOperand(T, OpLoc, R, isSizeOf)) 2095 return ExprError(); 2096 2097 // C99 6.5.3.4p4: the type (an unsigned integer type) is size_t. 2098 return Owned(new (Context) SizeOfAlignOfExpr(isSizeOf, TInfo, 2099 Context.getSizeType(), OpLoc, 2100 R.getEnd())); 2101} 2102 2103/// \brief Build a sizeof or alignof expression given an expression 2104/// operand. 2105Action::OwningExprResult 2106Sema::CreateSizeOfAlignOfExpr(Expr *E, SourceLocation OpLoc, 2107 bool isSizeOf, SourceRange R) { 2108 // Verify that the operand is valid. 2109 bool isInvalid = false; 2110 if (E->isTypeDependent()) { 2111 // Delay type-checking for type-dependent expressions. 2112 } else if (!isSizeOf) { 2113 isInvalid = CheckAlignOfExpr(E, OpLoc, R); 2114 } else if (E->getBitField()) { // C99 6.5.3.4p1. 2115 Diag(OpLoc, diag::err_sizeof_alignof_bitfield) << 0; 2116 isInvalid = true; 2117 } else { 2118 isInvalid = CheckSizeOfAlignOfOperand(E->getType(), OpLoc, R, true); 2119 } 2120 2121 if (isInvalid) 2122 return ExprError(); 2123 2124 // C99 6.5.3.4p4: the type (an unsigned integer type) is size_t. 2125 return Owned(new (Context) SizeOfAlignOfExpr(isSizeOf, E, 2126 Context.getSizeType(), OpLoc, 2127 R.getEnd())); 2128} 2129 2130/// ActOnSizeOfAlignOfExpr - Handle @c sizeof(type) and @c sizeof @c expr and 2131/// the same for @c alignof and @c __alignof 2132/// Note that the ArgRange is invalid if isType is false. 2133Action::OwningExprResult 2134Sema::ActOnSizeOfAlignOfExpr(SourceLocation OpLoc, bool isSizeof, bool isType, 2135 void *TyOrEx, const SourceRange &ArgRange) { 2136 // If error parsing type, ignore. 2137 if (TyOrEx == 0) return ExprError(); 2138 2139 if (isType) { 2140 TypeSourceInfo *TInfo; 2141 (void) GetTypeFromParser(TyOrEx, &TInfo); 2142 return CreateSizeOfAlignOfExpr(TInfo, OpLoc, isSizeof, ArgRange); 2143 } 2144 2145 Expr *ArgEx = (Expr *)TyOrEx; 2146 Action::OwningExprResult Result 2147 = CreateSizeOfAlignOfExpr(ArgEx, OpLoc, isSizeof, ArgEx->getSourceRange()); 2148 2149 if (Result.isInvalid()) 2150 DeleteExpr(ArgEx); 2151 2152 return move(Result); 2153} 2154 2155QualType Sema::CheckRealImagOperand(Expr *&V, SourceLocation Loc, bool isReal) { 2156 if (V->isTypeDependent()) 2157 return Context.DependentTy; 2158 2159 // These operators return the element type of a complex type. 2160 if (const ComplexType *CT = V->getType()->getAs<ComplexType>()) 2161 return CT->getElementType(); 2162 2163 // Otherwise they pass through real integer and floating point types here. 2164 if (V->getType()->isArithmeticType()) 2165 return V->getType(); 2166 2167 // Reject anything else. 2168 Diag(Loc, diag::err_realimag_invalid_type) << V->getType() 2169 << (isReal ? "__real" : "__imag"); 2170 return QualType(); 2171} 2172 2173 2174 2175Action::OwningExprResult 2176Sema::ActOnPostfixUnaryOp(Scope *S, SourceLocation OpLoc, 2177 tok::TokenKind Kind, ExprArg Input) { 2178 UnaryOperator::Opcode Opc; 2179 switch (Kind) { 2180 default: assert(0 && "Unknown unary op!"); 2181 case tok::plusplus: Opc = UnaryOperator::PostInc; break; 2182 case tok::minusminus: Opc = UnaryOperator::PostDec; break; 2183 } 2184 2185 return BuildUnaryOp(S, OpLoc, Opc, move(Input)); 2186} 2187 2188Action::OwningExprResult 2189Sema::ActOnArraySubscriptExpr(Scope *S, ExprArg Base, SourceLocation LLoc, 2190 ExprArg Idx, SourceLocation RLoc) { 2191 // Since this might be a postfix expression, get rid of ParenListExprs. 2192 Base = MaybeConvertParenListExprToParenExpr(S, move(Base)); 2193 2194 Expr *LHSExp = static_cast<Expr*>(Base.get()), 2195 *RHSExp = static_cast<Expr*>(Idx.get()); 2196 2197 if (getLangOptions().CPlusPlus && 2198 (LHSExp->isTypeDependent() || RHSExp->isTypeDependent())) { 2199 Base.release(); 2200 Idx.release(); 2201 return Owned(new (Context) ArraySubscriptExpr(LHSExp, RHSExp, 2202 Context.DependentTy, RLoc)); 2203 } 2204 2205 if (getLangOptions().CPlusPlus && 2206 (LHSExp->getType()->isRecordType() || 2207 LHSExp->getType()->isEnumeralType() || 2208 RHSExp->getType()->isRecordType() || 2209 RHSExp->getType()->isEnumeralType())) { 2210 return CreateOverloadedArraySubscriptExpr(LLoc, RLoc, move(Base),move(Idx)); 2211 } 2212 2213 return CreateBuiltinArraySubscriptExpr(move(Base), LLoc, move(Idx), RLoc); 2214} 2215 2216 2217Action::OwningExprResult 2218Sema::CreateBuiltinArraySubscriptExpr(ExprArg Base, SourceLocation LLoc, 2219 ExprArg Idx, SourceLocation RLoc) { 2220 Expr *LHSExp = static_cast<Expr*>(Base.get()); 2221 Expr *RHSExp = static_cast<Expr*>(Idx.get()); 2222 2223 // Perform default conversions. 2224 if (!LHSExp->getType()->getAs<VectorType>()) 2225 DefaultFunctionArrayLvalueConversion(LHSExp); 2226 DefaultFunctionArrayLvalueConversion(RHSExp); 2227 2228 QualType LHSTy = LHSExp->getType(), RHSTy = RHSExp->getType(); 2229 2230 // C99 6.5.2.1p2: the expression e1[e2] is by definition precisely equivalent 2231 // to the expression *((e1)+(e2)). This means the array "Base" may actually be 2232 // in the subscript position. As a result, we need to derive the array base 2233 // and index from the expression types. 2234 Expr *BaseExpr, *IndexExpr; 2235 QualType ResultType; 2236 if (LHSTy->isDependentType() || RHSTy->isDependentType()) { 2237 BaseExpr = LHSExp; 2238 IndexExpr = RHSExp; 2239 ResultType = Context.DependentTy; 2240 } else if (const PointerType *PTy = LHSTy->getAs<PointerType>()) { 2241 BaseExpr = LHSExp; 2242 IndexExpr = RHSExp; 2243 ResultType = PTy->getPointeeType(); 2244 } else if (const PointerType *PTy = RHSTy->getAs<PointerType>()) { 2245 // Handle the uncommon case of "123[Ptr]". 2246 BaseExpr = RHSExp; 2247 IndexExpr = LHSExp; 2248 ResultType = PTy->getPointeeType(); 2249 } else if (const ObjCObjectPointerType *PTy = 2250 LHSTy->getAs<ObjCObjectPointerType>()) { 2251 BaseExpr = LHSExp; 2252 IndexExpr = RHSExp; 2253 ResultType = PTy->getPointeeType(); 2254 } else if (const ObjCObjectPointerType *PTy = 2255 RHSTy->getAs<ObjCObjectPointerType>()) { 2256 // Handle the uncommon case of "123[Ptr]". 2257 BaseExpr = RHSExp; 2258 IndexExpr = LHSExp; 2259 ResultType = PTy->getPointeeType(); 2260 } else if (const VectorType *VTy = LHSTy->getAs<VectorType>()) { 2261 BaseExpr = LHSExp; // vectors: V[123] 2262 IndexExpr = RHSExp; 2263 2264 // FIXME: need to deal with const... 2265 ResultType = VTy->getElementType(); 2266 } else if (LHSTy->isArrayType()) { 2267 // If we see an array that wasn't promoted by 2268 // DefaultFunctionArrayLvalueConversion, it must be an array that 2269 // wasn't promoted because of the C90 rule that doesn't 2270 // allow promoting non-lvalue arrays. Warn, then 2271 // force the promotion here. 2272 Diag(LHSExp->getLocStart(), diag::ext_subscript_non_lvalue) << 2273 LHSExp->getSourceRange(); 2274 ImpCastExprToType(LHSExp, Context.getArrayDecayedType(LHSTy), 2275 CastExpr::CK_ArrayToPointerDecay); 2276 LHSTy = LHSExp->getType(); 2277 2278 BaseExpr = LHSExp; 2279 IndexExpr = RHSExp; 2280 ResultType = LHSTy->getAs<PointerType>()->getPointeeType(); 2281 } else if (RHSTy->isArrayType()) { 2282 // Same as previous, except for 123[f().a] case 2283 Diag(RHSExp->getLocStart(), diag::ext_subscript_non_lvalue) << 2284 RHSExp->getSourceRange(); 2285 ImpCastExprToType(RHSExp, Context.getArrayDecayedType(RHSTy), 2286 CastExpr::CK_ArrayToPointerDecay); 2287 RHSTy = RHSExp->getType(); 2288 2289 BaseExpr = RHSExp; 2290 IndexExpr = LHSExp; 2291 ResultType = RHSTy->getAs<PointerType>()->getPointeeType(); 2292 } else { 2293 return ExprError(Diag(LLoc, diag::err_typecheck_subscript_value) 2294 << LHSExp->getSourceRange() << RHSExp->getSourceRange()); 2295 } 2296 // C99 6.5.2.1p1 2297 if (!(IndexExpr->getType()->isIntegerType() && 2298 IndexExpr->getType()->isScalarType()) && !IndexExpr->isTypeDependent()) 2299 return ExprError(Diag(LLoc, diag::err_typecheck_subscript_not_integer) 2300 << IndexExpr->getSourceRange()); 2301 2302 if ((IndexExpr->getType()->isSpecificBuiltinType(BuiltinType::Char_S) || 2303 IndexExpr->getType()->isSpecificBuiltinType(BuiltinType::Char_U)) 2304 && !IndexExpr->isTypeDependent()) 2305 Diag(LLoc, diag::warn_subscript_is_char) << IndexExpr->getSourceRange(); 2306 2307 // C99 6.5.2.1p1: "shall have type "pointer to *object* type". Similarly, 2308 // C++ [expr.sub]p1: The type "T" shall be a completely-defined object 2309 // type. Note that Functions are not objects, and that (in C99 parlance) 2310 // incomplete types are not object types. 2311 if (ResultType->isFunctionType()) { 2312 Diag(BaseExpr->getLocStart(), diag::err_subscript_function_type) 2313 << ResultType << BaseExpr->getSourceRange(); 2314 return ExprError(); 2315 } 2316 2317 if (!ResultType->isDependentType() && 2318 RequireCompleteType(LLoc, ResultType, 2319 PDiag(diag::err_subscript_incomplete_type) 2320 << BaseExpr->getSourceRange())) 2321 return ExprError(); 2322 2323 // Diagnose bad cases where we step over interface counts. 2324 if (ResultType->isObjCObjectType() && LangOpts.ObjCNonFragileABI) { 2325 Diag(LLoc, diag::err_subscript_nonfragile_interface) 2326 << ResultType << BaseExpr->getSourceRange(); 2327 return ExprError(); 2328 } 2329 2330 Base.release(); 2331 Idx.release(); 2332 return Owned(new (Context) ArraySubscriptExpr(LHSExp, RHSExp, 2333 ResultType, RLoc)); 2334} 2335 2336QualType Sema:: 2337CheckExtVectorComponent(QualType baseType, SourceLocation OpLoc, 2338 const IdentifierInfo *CompName, 2339 SourceLocation CompLoc) { 2340 // FIXME: Share logic with ExtVectorElementExpr::containsDuplicateElements, 2341 // see FIXME there. 2342 // 2343 // FIXME: This logic can be greatly simplified by splitting it along 2344 // halving/not halving and reworking the component checking. 2345 const ExtVectorType *vecType = baseType->getAs<ExtVectorType>(); 2346 2347 // The vector accessor can't exceed the number of elements. 2348 const char *compStr = CompName->getNameStart(); 2349 2350 // This flag determines whether or not the component is one of the four 2351 // special names that indicate a subset of exactly half the elements are 2352 // to be selected. 2353 bool HalvingSwizzle = false; 2354 2355 // This flag determines whether or not CompName has an 's' char prefix, 2356 // indicating that it is a string of hex values to be used as vector indices. 2357 bool HexSwizzle = *compStr == 's' || *compStr == 'S'; 2358 2359 // Check that we've found one of the special components, or that the component 2360 // names must come from the same set. 2361 if (!strcmp(compStr, "hi") || !strcmp(compStr, "lo") || 2362 !strcmp(compStr, "even") || !strcmp(compStr, "odd")) { 2363 HalvingSwizzle = true; 2364 } else if (vecType->getPointAccessorIdx(*compStr) != -1) { 2365 do 2366 compStr++; 2367 while (*compStr && vecType->getPointAccessorIdx(*compStr) != -1); 2368 } else if (HexSwizzle || vecType->getNumericAccessorIdx(*compStr) != -1) { 2369 do 2370 compStr++; 2371 while (*compStr && vecType->getNumericAccessorIdx(*compStr) != -1); 2372 } 2373 2374 if (!HalvingSwizzle && *compStr) { 2375 // We didn't get to the end of the string. This means the component names 2376 // didn't come from the same set *or* we encountered an illegal name. 2377 Diag(OpLoc, diag::err_ext_vector_component_name_illegal) 2378 << std::string(compStr,compStr+1) << SourceRange(CompLoc); 2379 return QualType(); 2380 } 2381 2382 // Ensure no component accessor exceeds the width of the vector type it 2383 // operates on. 2384 if (!HalvingSwizzle) { 2385 compStr = CompName->getNameStart(); 2386 2387 if (HexSwizzle) 2388 compStr++; 2389 2390 while (*compStr) { 2391 if (!vecType->isAccessorWithinNumElements(*compStr++)) { 2392 Diag(OpLoc, diag::err_ext_vector_component_exceeds_length) 2393 << baseType << SourceRange(CompLoc); 2394 return QualType(); 2395 } 2396 } 2397 } 2398 2399 // The component accessor looks fine - now we need to compute the actual type. 2400 // The vector type is implied by the component accessor. For example, 2401 // vec4.b is a float, vec4.xy is a vec2, vec4.rgb is a vec3, etc. 2402 // vec4.s0 is a float, vec4.s23 is a vec3, etc. 2403 // vec4.hi, vec4.lo, vec4.e, and vec4.o all return vec2. 2404 unsigned CompSize = HalvingSwizzle ? (vecType->getNumElements() + 1) / 2 2405 : CompName->getLength(); 2406 if (HexSwizzle) 2407 CompSize--; 2408 2409 if (CompSize == 1) 2410 return vecType->getElementType(); 2411 2412 QualType VT = Context.getExtVectorType(vecType->getElementType(), CompSize); 2413 // Now look up the TypeDefDecl from the vector type. Without this, 2414 // diagostics look bad. We want extended vector types to appear built-in. 2415 for (unsigned i = 0, E = ExtVectorDecls.size(); i != E; ++i) { 2416 if (ExtVectorDecls[i]->getUnderlyingType() == VT) 2417 return Context.getTypedefType(ExtVectorDecls[i]); 2418 } 2419 return VT; // should never get here (a typedef type should always be found). 2420} 2421 2422static Decl *FindGetterNameDeclFromProtocolList(const ObjCProtocolDecl*PDecl, 2423 IdentifierInfo *Member, 2424 const Selector &Sel, 2425 ASTContext &Context) { 2426 2427 if (ObjCPropertyDecl *PD = PDecl->FindPropertyDeclaration(Member)) 2428 return PD; 2429 if (ObjCMethodDecl *OMD = PDecl->getInstanceMethod(Sel)) 2430 return OMD; 2431 2432 for (ObjCProtocolDecl::protocol_iterator I = PDecl->protocol_begin(), 2433 E = PDecl->protocol_end(); I != E; ++I) { 2434 if (Decl *D = FindGetterNameDeclFromProtocolList(*I, Member, Sel, 2435 Context)) 2436 return D; 2437 } 2438 return 0; 2439} 2440 2441static Decl *FindGetterNameDecl(const ObjCObjectPointerType *QIdTy, 2442 IdentifierInfo *Member, 2443 const Selector &Sel, 2444 ASTContext &Context) { 2445 // Check protocols on qualified interfaces. 2446 Decl *GDecl = 0; 2447 for (ObjCObjectPointerType::qual_iterator I = QIdTy->qual_begin(), 2448 E = QIdTy->qual_end(); I != E; ++I) { 2449 if (ObjCPropertyDecl *PD = (*I)->FindPropertyDeclaration(Member)) { 2450 GDecl = PD; 2451 break; 2452 } 2453 // Also must look for a getter name which uses property syntax. 2454 if (ObjCMethodDecl *OMD = (*I)->getInstanceMethod(Sel)) { 2455 GDecl = OMD; 2456 break; 2457 } 2458 } 2459 if (!GDecl) { 2460 for (ObjCObjectPointerType::qual_iterator I = QIdTy->qual_begin(), 2461 E = QIdTy->qual_end(); I != E; ++I) { 2462 // Search in the protocol-qualifier list of current protocol. 2463 GDecl = FindGetterNameDeclFromProtocolList(*I, Member, Sel, Context); 2464 if (GDecl) 2465 return GDecl; 2466 } 2467 } 2468 return GDecl; 2469} 2470 2471Sema::OwningExprResult 2472Sema::ActOnDependentMemberExpr(ExprArg Base, QualType BaseType, 2473 bool IsArrow, SourceLocation OpLoc, 2474 const CXXScopeSpec &SS, 2475 NamedDecl *FirstQualifierInScope, 2476 DeclarationName Name, SourceLocation NameLoc, 2477 const TemplateArgumentListInfo *TemplateArgs) { 2478 Expr *BaseExpr = Base.takeAs<Expr>(); 2479 2480 // Even in dependent contexts, try to diagnose base expressions with 2481 // obviously wrong types, e.g.: 2482 // 2483 // T* t; 2484 // t.f; 2485 // 2486 // In Obj-C++, however, the above expression is valid, since it could be 2487 // accessing the 'f' property if T is an Obj-C interface. The extra check 2488 // allows this, while still reporting an error if T is a struct pointer. 2489 if (!IsArrow) { 2490 const PointerType *PT = BaseType->getAs<PointerType>(); 2491 if (PT && (!getLangOptions().ObjC1 || 2492 PT->getPointeeType()->isRecordType())) { 2493 assert(BaseExpr && "cannot happen with implicit member accesses"); 2494 Diag(NameLoc, diag::err_typecheck_member_reference_struct_union) 2495 << BaseType << BaseExpr->getSourceRange(); 2496 return ExprError(); 2497 } 2498 } 2499 2500 assert(BaseType->isDependentType() || Name.isDependentName() || 2501 isDependentScopeSpecifier(SS)); 2502 2503 // Get the type being accessed in BaseType. If this is an arrow, the BaseExpr 2504 // must have pointer type, and the accessed type is the pointee. 2505 return Owned(CXXDependentScopeMemberExpr::Create(Context, BaseExpr, BaseType, 2506 IsArrow, OpLoc, 2507 static_cast<NestedNameSpecifier*>(SS.getScopeRep()), 2508 SS.getRange(), 2509 FirstQualifierInScope, 2510 Name, NameLoc, 2511 TemplateArgs)); 2512} 2513 2514/// We know that the given qualified member reference points only to 2515/// declarations which do not belong to the static type of the base 2516/// expression. Diagnose the problem. 2517static void DiagnoseQualifiedMemberReference(Sema &SemaRef, 2518 Expr *BaseExpr, 2519 QualType BaseType, 2520 const CXXScopeSpec &SS, 2521 const LookupResult &R) { 2522 // If this is an implicit member access, use a different set of 2523 // diagnostics. 2524 if (!BaseExpr) 2525 return DiagnoseInstanceReference(SemaRef, SS, R); 2526 2527 SemaRef.Diag(R.getNameLoc(), diag::err_qualified_member_of_unrelated) 2528 << SS.getRange() << R.getRepresentativeDecl() << BaseType; 2529} 2530 2531// Check whether the declarations we found through a nested-name 2532// specifier in a member expression are actually members of the base 2533// type. The restriction here is: 2534// 2535// C++ [expr.ref]p2: 2536// ... In these cases, the id-expression shall name a 2537// member of the class or of one of its base classes. 2538// 2539// So it's perfectly legitimate for the nested-name specifier to name 2540// an unrelated class, and for us to find an overload set including 2541// decls from classes which are not superclasses, as long as the decl 2542// we actually pick through overload resolution is from a superclass. 2543bool Sema::CheckQualifiedMemberReference(Expr *BaseExpr, 2544 QualType BaseType, 2545 const CXXScopeSpec &SS, 2546 const LookupResult &R) { 2547 const RecordType *BaseRT = BaseType->getAs<RecordType>(); 2548 if (!BaseRT) { 2549 // We can't check this yet because the base type is still 2550 // dependent. 2551 assert(BaseType->isDependentType()); 2552 return false; 2553 } 2554 CXXRecordDecl *BaseRecord = cast<CXXRecordDecl>(BaseRT->getDecl()); 2555 2556 for (LookupResult::iterator I = R.begin(), E = R.end(); I != E; ++I) { 2557 // If this is an implicit member reference and we find a 2558 // non-instance member, it's not an error. 2559 if (!BaseExpr && !(*I)->isCXXInstanceMember()) 2560 return false; 2561 2562 // Note that we use the DC of the decl, not the underlying decl. 2563 CXXRecordDecl *RecordD = cast<CXXRecordDecl>((*I)->getDeclContext()); 2564 while (RecordD->isAnonymousStructOrUnion()) 2565 RecordD = cast<CXXRecordDecl>(RecordD->getParent()); 2566 2567 llvm::SmallPtrSet<CXXRecordDecl*,4> MemberRecord; 2568 MemberRecord.insert(RecordD->getCanonicalDecl()); 2569 2570 if (!IsProvablyNotDerivedFrom(*this, BaseRecord, MemberRecord)) 2571 return false; 2572 } 2573 2574 DiagnoseQualifiedMemberReference(*this, BaseExpr, BaseType, SS, R); 2575 return true; 2576} 2577 2578static bool 2579LookupMemberExprInRecord(Sema &SemaRef, LookupResult &R, 2580 SourceRange BaseRange, const RecordType *RTy, 2581 SourceLocation OpLoc, CXXScopeSpec &SS, 2582 bool HasTemplateArgs) { 2583 RecordDecl *RDecl = RTy->getDecl(); 2584 if (SemaRef.RequireCompleteType(OpLoc, QualType(RTy, 0), 2585 SemaRef.PDiag(diag::err_typecheck_incomplete_tag) 2586 << BaseRange)) 2587 return true; 2588 2589 if (HasTemplateArgs) { 2590 // LookupTemplateName doesn't expect these both to exist simultaneously. 2591 QualType ObjectType = SS.isSet() ? QualType() : QualType(RTy, 0); 2592 2593 bool MOUS; 2594 SemaRef.LookupTemplateName(R, 0, SS, ObjectType, false, MOUS); 2595 return false; 2596 } 2597 2598 DeclContext *DC = RDecl; 2599 if (SS.isSet()) { 2600 // If the member name was a qualified-id, look into the 2601 // nested-name-specifier. 2602 DC = SemaRef.computeDeclContext(SS, false); 2603 2604 if (SemaRef.RequireCompleteDeclContext(SS, DC)) { 2605 SemaRef.Diag(SS.getRange().getEnd(), diag::err_typecheck_incomplete_tag) 2606 << SS.getRange() << DC; 2607 return true; 2608 } 2609 2610 assert(DC && "Cannot handle non-computable dependent contexts in lookup"); 2611 2612 if (!isa<TypeDecl>(DC)) { 2613 SemaRef.Diag(R.getNameLoc(), diag::err_qualified_member_nonclass) 2614 << DC << SS.getRange(); 2615 return true; 2616 } 2617 } 2618 2619 // The record definition is complete, now look up the member. 2620 SemaRef.LookupQualifiedName(R, DC); 2621 2622 if (!R.empty()) 2623 return false; 2624 2625 // We didn't find anything with the given name, so try to correct 2626 // for typos. 2627 DeclarationName Name = R.getLookupName(); 2628 if (SemaRef.CorrectTypo(R, 0, &SS, DC, false, Sema::CTC_MemberLookup) && 2629 !R.empty() && 2630 (isa<ValueDecl>(*R.begin()) || isa<FunctionTemplateDecl>(*R.begin()))) { 2631 SemaRef.Diag(R.getNameLoc(), diag::err_no_member_suggest) 2632 << Name << DC << R.getLookupName() << SS.getRange() 2633 << FixItHint::CreateReplacement(R.getNameLoc(), 2634 R.getLookupName().getAsString()); 2635 if (NamedDecl *ND = R.getAsSingle<NamedDecl>()) 2636 SemaRef.Diag(ND->getLocation(), diag::note_previous_decl) 2637 << ND->getDeclName(); 2638 return false; 2639 } else { 2640 R.clear(); 2641 R.setLookupName(Name); 2642 } 2643 2644 return false; 2645} 2646 2647Sema::OwningExprResult 2648Sema::BuildMemberReferenceExpr(ExprArg BaseArg, QualType BaseType, 2649 SourceLocation OpLoc, bool IsArrow, 2650 CXXScopeSpec &SS, 2651 NamedDecl *FirstQualifierInScope, 2652 DeclarationName Name, SourceLocation NameLoc, 2653 const TemplateArgumentListInfo *TemplateArgs) { 2654 Expr *Base = BaseArg.takeAs<Expr>(); 2655 2656 if (BaseType->isDependentType() || 2657 (SS.isSet() && isDependentScopeSpecifier(SS))) 2658 return ActOnDependentMemberExpr(ExprArg(*this, Base), BaseType, 2659 IsArrow, OpLoc, 2660 SS, FirstQualifierInScope, 2661 Name, NameLoc, 2662 TemplateArgs); 2663 2664 LookupResult R(*this, Name, NameLoc, LookupMemberName); 2665 2666 // Implicit member accesses. 2667 if (!Base) { 2668 QualType RecordTy = BaseType; 2669 if (IsArrow) RecordTy = RecordTy->getAs<PointerType>()->getPointeeType(); 2670 if (LookupMemberExprInRecord(*this, R, SourceRange(), 2671 RecordTy->getAs<RecordType>(), 2672 OpLoc, SS, TemplateArgs != 0)) 2673 return ExprError(); 2674 2675 // Explicit member accesses. 2676 } else { 2677 OwningExprResult Result = 2678 LookupMemberExpr(R, Base, IsArrow, OpLoc, 2679 SS, /*ObjCImpDecl*/ DeclPtrTy(), TemplateArgs != 0); 2680 2681 if (Result.isInvalid()) { 2682 Owned(Base); 2683 return ExprError(); 2684 } 2685 2686 if (Result.get()) 2687 return move(Result); 2688 2689 // LookupMemberExpr can modify Base, and thus change BaseType 2690 BaseType = Base->getType(); 2691 } 2692 2693 return BuildMemberReferenceExpr(ExprArg(*this, Base), BaseType, 2694 OpLoc, IsArrow, SS, FirstQualifierInScope, 2695 R, TemplateArgs); 2696} 2697 2698Sema::OwningExprResult 2699Sema::BuildMemberReferenceExpr(ExprArg Base, QualType BaseExprType, 2700 SourceLocation OpLoc, bool IsArrow, 2701 const CXXScopeSpec &SS, 2702 NamedDecl *FirstQualifierInScope, 2703 LookupResult &R, 2704 const TemplateArgumentListInfo *TemplateArgs, 2705 bool SuppressQualifierCheck) { 2706 Expr *BaseExpr = Base.takeAs<Expr>(); 2707 QualType BaseType = BaseExprType; 2708 if (IsArrow) { 2709 assert(BaseType->isPointerType()); 2710 BaseType = BaseType->getAs<PointerType>()->getPointeeType(); 2711 } 2712 R.setBaseObjectType(BaseType); 2713 2714 NestedNameSpecifier *Qualifier = 2715 static_cast<NestedNameSpecifier*>(SS.getScopeRep()); 2716 DeclarationName MemberName = R.getLookupName(); 2717 SourceLocation MemberLoc = R.getNameLoc(); 2718 2719 if (R.isAmbiguous()) 2720 return ExprError(); 2721 2722 if (R.empty()) { 2723 // Rederive where we looked up. 2724 DeclContext *DC = (SS.isSet() 2725 ? computeDeclContext(SS, false) 2726 : BaseType->getAs<RecordType>()->getDecl()); 2727 2728 Diag(R.getNameLoc(), diag::err_no_member) 2729 << MemberName << DC 2730 << (BaseExpr ? BaseExpr->getSourceRange() : SourceRange()); 2731 return ExprError(); 2732 } 2733 2734 // Diagnose lookups that find only declarations from a non-base 2735 // type. This is possible for either qualified lookups (which may 2736 // have been qualified with an unrelated type) or implicit member 2737 // expressions (which were found with unqualified lookup and thus 2738 // may have come from an enclosing scope). Note that it's okay for 2739 // lookup to find declarations from a non-base type as long as those 2740 // aren't the ones picked by overload resolution. 2741 if ((SS.isSet() || !BaseExpr || 2742 (isa<CXXThisExpr>(BaseExpr) && 2743 cast<CXXThisExpr>(BaseExpr)->isImplicit())) && 2744 !SuppressQualifierCheck && 2745 CheckQualifiedMemberReference(BaseExpr, BaseType, SS, R)) 2746 return ExprError(); 2747 2748 // Construct an unresolved result if we in fact got an unresolved 2749 // result. 2750 if (R.isOverloadedResult() || R.isUnresolvableResult()) { 2751 bool Dependent = 2752 BaseExprType->isDependentType() || 2753 R.isUnresolvableResult() || 2754 OverloadExpr::ComputeDependence(R.begin(), R.end(), TemplateArgs); 2755 2756 // Suppress any lookup-related diagnostics; we'll do these when we 2757 // pick a member. 2758 R.suppressDiagnostics(); 2759 2760 UnresolvedMemberExpr *MemExpr 2761 = UnresolvedMemberExpr::Create(Context, Dependent, 2762 R.isUnresolvableResult(), 2763 BaseExpr, BaseExprType, 2764 IsArrow, OpLoc, 2765 Qualifier, SS.getRange(), 2766 MemberName, MemberLoc, 2767 TemplateArgs, R.begin(), R.end()); 2768 2769 return Owned(MemExpr); 2770 } 2771 2772 assert(R.isSingleResult()); 2773 DeclAccessPair FoundDecl = R.begin().getPair(); 2774 NamedDecl *MemberDecl = R.getFoundDecl(); 2775 2776 // FIXME: diagnose the presence of template arguments now. 2777 2778 // If the decl being referenced had an error, return an error for this 2779 // sub-expr without emitting another error, in order to avoid cascading 2780 // error cases. 2781 if (MemberDecl->isInvalidDecl()) 2782 return ExprError(); 2783 2784 // Handle the implicit-member-access case. 2785 if (!BaseExpr) { 2786 // If this is not an instance member, convert to a non-member access. 2787 if (!MemberDecl->isCXXInstanceMember()) 2788 return BuildDeclarationNameExpr(SS, R.getNameLoc(), MemberDecl); 2789 2790 SourceLocation Loc = R.getNameLoc(); 2791 if (SS.getRange().isValid()) 2792 Loc = SS.getRange().getBegin(); 2793 BaseExpr = new (Context) CXXThisExpr(Loc, BaseExprType,/*isImplicit=*/true); 2794 } 2795 2796 bool ShouldCheckUse = true; 2797 if (CXXMethodDecl *MD = dyn_cast<CXXMethodDecl>(MemberDecl)) { 2798 // Don't diagnose the use of a virtual member function unless it's 2799 // explicitly qualified. 2800 if (MD->isVirtual() && !SS.isSet()) 2801 ShouldCheckUse = false; 2802 } 2803 2804 // Check the use of this member. 2805 if (ShouldCheckUse && DiagnoseUseOfDecl(MemberDecl, MemberLoc)) { 2806 Owned(BaseExpr); 2807 return ExprError(); 2808 } 2809 2810 if (FieldDecl *FD = dyn_cast<FieldDecl>(MemberDecl)) { 2811 // We may have found a field within an anonymous union or struct 2812 // (C++ [class.union]). 2813 if (cast<RecordDecl>(FD->getDeclContext())->isAnonymousStructOrUnion() && 2814 !BaseType->getAs<RecordType>()->getDecl()->isAnonymousStructOrUnion()) 2815 return BuildAnonymousStructUnionMemberReference(MemberLoc, FD, 2816 BaseExpr, OpLoc); 2817 2818 // Figure out the type of the member; see C99 6.5.2.3p3, C++ [expr.ref] 2819 QualType MemberType = FD->getType(); 2820 if (const ReferenceType *Ref = MemberType->getAs<ReferenceType>()) 2821 MemberType = Ref->getPointeeType(); 2822 else { 2823 Qualifiers BaseQuals = BaseType.getQualifiers(); 2824 BaseQuals.removeObjCGCAttr(); 2825 if (FD->isMutable()) BaseQuals.removeConst(); 2826 2827 Qualifiers MemberQuals 2828 = Context.getCanonicalType(MemberType).getQualifiers(); 2829 2830 Qualifiers Combined = BaseQuals + MemberQuals; 2831 if (Combined != MemberQuals) 2832 MemberType = Context.getQualifiedType(MemberType, Combined); 2833 } 2834 2835 MarkDeclarationReferenced(MemberLoc, FD); 2836 if (PerformObjectMemberConversion(BaseExpr, Qualifier, FoundDecl, FD)) 2837 return ExprError(); 2838 return Owned(BuildMemberExpr(Context, BaseExpr, IsArrow, SS, 2839 FD, FoundDecl, MemberLoc, MemberType)); 2840 } 2841 2842 if (VarDecl *Var = dyn_cast<VarDecl>(MemberDecl)) { 2843 MarkDeclarationReferenced(MemberLoc, Var); 2844 return Owned(BuildMemberExpr(Context, BaseExpr, IsArrow, SS, 2845 Var, FoundDecl, MemberLoc, 2846 Var->getType().getNonReferenceType())); 2847 } 2848 2849 if (FunctionDecl *MemberFn = dyn_cast<FunctionDecl>(MemberDecl)) { 2850 MarkDeclarationReferenced(MemberLoc, MemberDecl); 2851 return Owned(BuildMemberExpr(Context, BaseExpr, IsArrow, SS, 2852 MemberFn, FoundDecl, MemberLoc, 2853 MemberFn->getType())); 2854 } 2855 2856 if (EnumConstantDecl *Enum = dyn_cast<EnumConstantDecl>(MemberDecl)) { 2857 MarkDeclarationReferenced(MemberLoc, MemberDecl); 2858 return Owned(BuildMemberExpr(Context, BaseExpr, IsArrow, SS, 2859 Enum, FoundDecl, MemberLoc, Enum->getType())); 2860 } 2861 2862 Owned(BaseExpr); 2863 2864 // We found something that we didn't expect. Complain. 2865 if (isa<TypeDecl>(MemberDecl)) 2866 Diag(MemberLoc,diag::err_typecheck_member_reference_type) 2867 << MemberName << BaseType << int(IsArrow); 2868 else 2869 Diag(MemberLoc, diag::err_typecheck_member_reference_unknown) 2870 << MemberName << BaseType << int(IsArrow); 2871 2872 Diag(MemberDecl->getLocation(), diag::note_member_declared_here) 2873 << MemberName; 2874 R.suppressDiagnostics(); 2875 return ExprError(); 2876} 2877 2878/// Look up the given member of the given non-type-dependent 2879/// expression. This can return in one of two ways: 2880/// * If it returns a sentinel null-but-valid result, the caller will 2881/// assume that lookup was performed and the results written into 2882/// the provided structure. It will take over from there. 2883/// * Otherwise, the returned expression will be produced in place of 2884/// an ordinary member expression. 2885/// 2886/// The ObjCImpDecl bit is a gross hack that will need to be properly 2887/// fixed for ObjC++. 2888Sema::OwningExprResult 2889Sema::LookupMemberExpr(LookupResult &R, Expr *&BaseExpr, 2890 bool &IsArrow, SourceLocation OpLoc, 2891 CXXScopeSpec &SS, 2892 DeclPtrTy ObjCImpDecl, bool HasTemplateArgs) { 2893 assert(BaseExpr && "no base expression"); 2894 2895 // Perform default conversions. 2896 DefaultFunctionArrayConversion(BaseExpr); 2897 2898 QualType BaseType = BaseExpr->getType(); 2899 assert(!BaseType->isDependentType()); 2900 2901 DeclarationName MemberName = R.getLookupName(); 2902 SourceLocation MemberLoc = R.getNameLoc(); 2903 2904 // If the user is trying to apply -> or . to a function pointer 2905 // type, it's probably because they forgot parentheses to call that 2906 // function. Suggest the addition of those parentheses, build the 2907 // call, and continue on. 2908 if (const PointerType *Ptr = BaseType->getAs<PointerType>()) { 2909 if (const FunctionProtoType *Fun 2910 = Ptr->getPointeeType()->getAs<FunctionProtoType>()) { 2911 QualType ResultTy = Fun->getResultType(); 2912 if (Fun->getNumArgs() == 0 && 2913 ((!IsArrow && ResultTy->isRecordType()) || 2914 (IsArrow && ResultTy->isPointerType() && 2915 ResultTy->getAs<PointerType>()->getPointeeType() 2916 ->isRecordType()))) { 2917 SourceLocation Loc = PP.getLocForEndOfToken(BaseExpr->getLocEnd()); 2918 Diag(Loc, diag::err_member_reference_needs_call) 2919 << QualType(Fun, 0) 2920 << FixItHint::CreateInsertion(Loc, "()"); 2921 2922 OwningExprResult NewBase 2923 = ActOnCallExpr(0, ExprArg(*this, BaseExpr), Loc, 2924 MultiExprArg(*this, 0, 0), 0, Loc); 2925 BaseExpr = 0; 2926 if (NewBase.isInvalid()) 2927 return ExprError(); 2928 2929 BaseExpr = NewBase.takeAs<Expr>(); 2930 DefaultFunctionArrayConversion(BaseExpr); 2931 BaseType = BaseExpr->getType(); 2932 } 2933 } 2934 } 2935 2936 // If this is an Objective-C pseudo-builtin and a definition is provided then 2937 // use that. 2938 if (BaseType->isObjCIdType()) { 2939 if (IsArrow) { 2940 // Handle the following exceptional case PObj->isa. 2941 if (const ObjCObjectPointerType *OPT = 2942 BaseType->getAs<ObjCObjectPointerType>()) { 2943 if (OPT->getObjectType()->isObjCId() && 2944 MemberName.getAsIdentifierInfo()->isStr("isa")) 2945 return Owned(new (Context) ObjCIsaExpr(BaseExpr, true, MemberLoc, 2946 Context.getObjCClassType())); 2947 } 2948 } 2949 // We have an 'id' type. Rather than fall through, we check if this 2950 // is a reference to 'isa'. 2951 if (BaseType != Context.ObjCIdRedefinitionType) { 2952 BaseType = Context.ObjCIdRedefinitionType; 2953 ImpCastExprToType(BaseExpr, BaseType, CastExpr::CK_BitCast); 2954 } 2955 } 2956 2957 // If this is an Objective-C pseudo-builtin and a definition is provided then 2958 // use that. 2959 if (Context.isObjCSelType(BaseType)) { 2960 // We have an 'SEL' type. Rather than fall through, we check if this 2961 // is a reference to 'sel_id'. 2962 if (BaseType != Context.ObjCSelRedefinitionType) { 2963 BaseType = Context.ObjCSelRedefinitionType; 2964 ImpCastExprToType(BaseExpr, BaseType, CastExpr::CK_BitCast); 2965 } 2966 } 2967 2968 assert(!BaseType.isNull() && "no type for member expression"); 2969 2970 // Handle properties on ObjC 'Class' types. 2971 if (!IsArrow && BaseType->isObjCClassType()) { 2972 // Also must look for a getter name which uses property syntax. 2973 IdentifierInfo *Member = MemberName.getAsIdentifierInfo(); 2974 Selector Sel = PP.getSelectorTable().getNullarySelector(Member); 2975 if (ObjCMethodDecl *MD = getCurMethodDecl()) { 2976 ObjCInterfaceDecl *IFace = MD->getClassInterface(); 2977 ObjCMethodDecl *Getter; 2978 // FIXME: need to also look locally in the implementation. 2979 if ((Getter = IFace->lookupClassMethod(Sel))) { 2980 // Check the use of this method. 2981 if (DiagnoseUseOfDecl(Getter, MemberLoc)) 2982 return ExprError(); 2983 } 2984 // If we found a getter then this may be a valid dot-reference, we 2985 // will look for the matching setter, in case it is needed. 2986 Selector SetterSel = 2987 SelectorTable::constructSetterName(PP.getIdentifierTable(), 2988 PP.getSelectorTable(), Member); 2989 ObjCMethodDecl *Setter = IFace->lookupClassMethod(SetterSel); 2990 if (!Setter) { 2991 // If this reference is in an @implementation, also check for 'private' 2992 // methods. 2993 Setter = IFace->lookupPrivateInstanceMethod(SetterSel); 2994 } 2995 // Look through local category implementations associated with the class. 2996 if (!Setter) 2997 Setter = IFace->getCategoryClassMethod(SetterSel); 2998 2999 if (Setter && DiagnoseUseOfDecl(Setter, MemberLoc)) 3000 return ExprError(); 3001 3002 if (Getter || Setter) { 3003 QualType PType; 3004 3005 if (Getter) 3006 PType = Getter->getResultType(); 3007 else 3008 // Get the expression type from Setter's incoming parameter. 3009 PType = (*(Setter->param_end() -1))->getType(); 3010 // FIXME: we must check that the setter has property type. 3011 return Owned(new (Context) ObjCImplicitSetterGetterRefExpr(Getter, 3012 PType, 3013 Setter, MemberLoc, BaseExpr)); 3014 } 3015 return ExprError(Diag(MemberLoc, diag::err_property_not_found) 3016 << MemberName << BaseType); 3017 } 3018 } 3019 3020 if (BaseType->isObjCClassType() && 3021 BaseType != Context.ObjCClassRedefinitionType) { 3022 BaseType = Context.ObjCClassRedefinitionType; 3023 ImpCastExprToType(BaseExpr, BaseType, CastExpr::CK_BitCast); 3024 } 3025 3026 if (IsArrow) { 3027 if (const PointerType *PT = BaseType->getAs<PointerType>()) 3028 BaseType = PT->getPointeeType(); 3029 else if (BaseType->isObjCObjectPointerType()) 3030 ; 3031 else if (BaseType->isRecordType()) { 3032 // Recover from arrow accesses to records, e.g.: 3033 // struct MyRecord foo; 3034 // foo->bar 3035 // This is actually well-formed in C++ if MyRecord has an 3036 // overloaded operator->, but that should have been dealt with 3037 // by now. 3038 Diag(OpLoc, diag::err_typecheck_member_reference_suggestion) 3039 << BaseType << int(IsArrow) << BaseExpr->getSourceRange() 3040 << FixItHint::CreateReplacement(OpLoc, "."); 3041 IsArrow = false; 3042 } else { 3043 Diag(MemberLoc, diag::err_typecheck_member_reference_arrow) 3044 << BaseType << BaseExpr->getSourceRange(); 3045 return ExprError(); 3046 } 3047 } else { 3048 // Recover from dot accesses to pointers, e.g.: 3049 // type *foo; 3050 // foo.bar 3051 // This is actually well-formed in two cases: 3052 // - 'type' is an Objective C type 3053 // - 'bar' is a pseudo-destructor name which happens to refer to 3054 // the appropriate pointer type 3055 if (MemberName.getNameKind() != DeclarationName::CXXDestructorName) { 3056 const PointerType *PT = BaseType->getAs<PointerType>(); 3057 if (PT && PT->getPointeeType()->isRecordType()) { 3058 Diag(OpLoc, diag::err_typecheck_member_reference_suggestion) 3059 << BaseType << int(IsArrow) << BaseExpr->getSourceRange() 3060 << FixItHint::CreateReplacement(OpLoc, "->"); 3061 BaseType = PT->getPointeeType(); 3062 IsArrow = true; 3063 } 3064 } 3065 } 3066 3067 // Handle field access to simple records. 3068 if (const RecordType *RTy = BaseType->getAs<RecordType>()) { 3069 if (LookupMemberExprInRecord(*this, R, BaseExpr->getSourceRange(), 3070 RTy, OpLoc, SS, HasTemplateArgs)) 3071 return ExprError(); 3072 return Owned((Expr*) 0); 3073 } 3074 3075 // Handle access to Objective-C instance variables, such as "Obj->ivar" and 3076 // (*Obj).ivar. 3077 if ((IsArrow && BaseType->isObjCObjectPointerType()) || 3078 (!IsArrow && BaseType->isObjCObjectType())) { 3079 const ObjCObjectPointerType *OPT = BaseType->getAs<ObjCObjectPointerType>(); 3080 ObjCInterfaceDecl *IDecl = 3081 OPT ? OPT->getInterfaceDecl() 3082 : BaseType->getAs<ObjCObjectType>()->getInterface(); 3083 if (IDecl) { 3084 IdentifierInfo *Member = MemberName.getAsIdentifierInfo(); 3085 3086 ObjCInterfaceDecl *ClassDeclared; 3087 ObjCIvarDecl *IV = IDecl->lookupInstanceVariable(Member, ClassDeclared); 3088 3089 if (!IV) { 3090 // Attempt to correct for typos in ivar names. 3091 LookupResult Res(*this, R.getLookupName(), R.getNameLoc(), 3092 LookupMemberName); 3093 if (CorrectTypo(Res, 0, 0, IDecl, false, CTC_MemberLookup) && 3094 (IV = Res.getAsSingle<ObjCIvarDecl>())) { 3095 Diag(R.getNameLoc(), 3096 diag::err_typecheck_member_reference_ivar_suggest) 3097 << IDecl->getDeclName() << MemberName << IV->getDeclName() 3098 << FixItHint::CreateReplacement(R.getNameLoc(), 3099 IV->getNameAsString()); 3100 Diag(IV->getLocation(), diag::note_previous_decl) 3101 << IV->getDeclName(); 3102 } else { 3103 Res.clear(); 3104 Res.setLookupName(Member); 3105 } 3106 } 3107 3108 if (IV) { 3109 // If the decl being referenced had an error, return an error for this 3110 // sub-expr without emitting another error, in order to avoid cascading 3111 // error cases. 3112 if (IV->isInvalidDecl()) 3113 return ExprError(); 3114 3115 // Check whether we can reference this field. 3116 if (DiagnoseUseOfDecl(IV, MemberLoc)) 3117 return ExprError(); 3118 if (IV->getAccessControl() != ObjCIvarDecl::Public && 3119 IV->getAccessControl() != ObjCIvarDecl::Package) { 3120 ObjCInterfaceDecl *ClassOfMethodDecl = 0; 3121 if (ObjCMethodDecl *MD = getCurMethodDecl()) 3122 ClassOfMethodDecl = MD->getClassInterface(); 3123 else if (ObjCImpDecl && getCurFunctionDecl()) { 3124 // Case of a c-function declared inside an objc implementation. 3125 // FIXME: For a c-style function nested inside an objc implementation 3126 // class, there is no implementation context available, so we pass 3127 // down the context as argument to this routine. Ideally, this context 3128 // need be passed down in the AST node and somehow calculated from the 3129 // AST for a function decl. 3130 Decl *ImplDecl = ObjCImpDecl.getAs<Decl>(); 3131 if (ObjCImplementationDecl *IMPD = 3132 dyn_cast<ObjCImplementationDecl>(ImplDecl)) 3133 ClassOfMethodDecl = IMPD->getClassInterface(); 3134 else if (ObjCCategoryImplDecl* CatImplClass = 3135 dyn_cast<ObjCCategoryImplDecl>(ImplDecl)) 3136 ClassOfMethodDecl = CatImplClass->getClassInterface(); 3137 } 3138 3139 if (IV->getAccessControl() == ObjCIvarDecl::Private) { 3140 if (ClassDeclared != IDecl || 3141 ClassOfMethodDecl != ClassDeclared) 3142 Diag(MemberLoc, diag::error_private_ivar_access) 3143 << IV->getDeclName(); 3144 } else if (!IDecl->isSuperClassOf(ClassOfMethodDecl)) 3145 // @protected 3146 Diag(MemberLoc, diag::error_protected_ivar_access) 3147 << IV->getDeclName(); 3148 } 3149 3150 return Owned(new (Context) ObjCIvarRefExpr(IV, IV->getType(), 3151 MemberLoc, BaseExpr, 3152 IsArrow)); 3153 } 3154 return ExprError(Diag(MemberLoc, diag::err_typecheck_member_reference_ivar) 3155 << IDecl->getDeclName() << MemberName 3156 << BaseExpr->getSourceRange()); 3157 } 3158 } 3159 // Handle properties on 'id' and qualified "id". 3160 if (!IsArrow && (BaseType->isObjCIdType() || 3161 BaseType->isObjCQualifiedIdType())) { 3162 const ObjCObjectPointerType *QIdTy = BaseType->getAs<ObjCObjectPointerType>(); 3163 IdentifierInfo *Member = MemberName.getAsIdentifierInfo(); 3164 3165 // Check protocols on qualified interfaces. 3166 Selector Sel = PP.getSelectorTable().getNullarySelector(Member); 3167 if (Decl *PMDecl = FindGetterNameDecl(QIdTy, Member, Sel, Context)) { 3168 if (ObjCPropertyDecl *PD = dyn_cast<ObjCPropertyDecl>(PMDecl)) { 3169 // Check the use of this declaration 3170 if (DiagnoseUseOfDecl(PD, MemberLoc)) 3171 return ExprError(); 3172 3173 return Owned(new (Context) ObjCPropertyRefExpr(PD, PD->getType(), 3174 MemberLoc, BaseExpr)); 3175 } 3176 if (ObjCMethodDecl *OMD = dyn_cast<ObjCMethodDecl>(PMDecl)) { 3177 // Check the use of this method. 3178 if (DiagnoseUseOfDecl(OMD, MemberLoc)) 3179 return ExprError(); 3180 3181 return Owned(ObjCMessageExpr::Create(Context, 3182 OMD->getResultType().getNonReferenceType(), 3183 OpLoc, BaseExpr, Sel, 3184 OMD, NULL, 0, MemberLoc)); 3185 } 3186 } 3187 3188 return ExprError(Diag(MemberLoc, diag::err_property_not_found) 3189 << MemberName << BaseType); 3190 } 3191 3192 // Handle Objective-C property access, which is "Obj.property" where Obj is a 3193 // pointer to a (potentially qualified) interface type. 3194 if (!IsArrow) 3195 if (const ObjCObjectPointerType *OPT = 3196 BaseType->getAsObjCInterfacePointerType()) 3197 return HandleExprPropertyRefExpr(OPT, BaseExpr, MemberName, MemberLoc); 3198 3199 // Handle the following exceptional case (*Obj).isa. 3200 if (!IsArrow && 3201 BaseType->isObjCObjectType() && 3202 BaseType->getAs<ObjCObjectType>()->isObjCId() && 3203 MemberName.getAsIdentifierInfo()->isStr("isa")) 3204 return Owned(new (Context) ObjCIsaExpr(BaseExpr, false, MemberLoc, 3205 Context.getObjCClassType())); 3206 3207 // Handle 'field access' to vectors, such as 'V.xx'. 3208 if (BaseType->isExtVectorType()) { 3209 IdentifierInfo *Member = MemberName.getAsIdentifierInfo(); 3210 QualType ret = CheckExtVectorComponent(BaseType, OpLoc, Member, MemberLoc); 3211 if (ret.isNull()) 3212 return ExprError(); 3213 return Owned(new (Context) ExtVectorElementExpr(ret, BaseExpr, *Member, 3214 MemberLoc)); 3215 } 3216 3217 Diag(MemberLoc, diag::err_typecheck_member_reference_struct_union) 3218 << BaseType << BaseExpr->getSourceRange(); 3219 3220 return ExprError(); 3221} 3222 3223/// The main callback when the parser finds something like 3224/// expression . [nested-name-specifier] identifier 3225/// expression -> [nested-name-specifier] identifier 3226/// where 'identifier' encompasses a fairly broad spectrum of 3227/// possibilities, including destructor and operator references. 3228/// 3229/// \param OpKind either tok::arrow or tok::period 3230/// \param HasTrailingLParen whether the next token is '(', which 3231/// is used to diagnose mis-uses of special members that can 3232/// only be called 3233/// \param ObjCImpDecl the current ObjC @implementation decl; 3234/// this is an ugly hack around the fact that ObjC @implementations 3235/// aren't properly put in the context chain 3236Sema::OwningExprResult Sema::ActOnMemberAccessExpr(Scope *S, ExprArg BaseArg, 3237 SourceLocation OpLoc, 3238 tok::TokenKind OpKind, 3239 CXXScopeSpec &SS, 3240 UnqualifiedId &Id, 3241 DeclPtrTy ObjCImpDecl, 3242 bool HasTrailingLParen) { 3243 if (SS.isSet() && SS.isInvalid()) 3244 return ExprError(); 3245 3246 TemplateArgumentListInfo TemplateArgsBuffer; 3247 3248 // Decompose the name into its component parts. 3249 DeclarationName Name; 3250 SourceLocation NameLoc; 3251 const TemplateArgumentListInfo *TemplateArgs; 3252 DecomposeUnqualifiedId(*this, Id, TemplateArgsBuffer, 3253 Name, NameLoc, TemplateArgs); 3254 3255 bool IsArrow = (OpKind == tok::arrow); 3256 3257 NamedDecl *FirstQualifierInScope 3258 = (!SS.isSet() ? 0 : FindFirstQualifierInScope(S, 3259 static_cast<NestedNameSpecifier*>(SS.getScopeRep()))); 3260 3261 // This is a postfix expression, so get rid of ParenListExprs. 3262 BaseArg = MaybeConvertParenListExprToParenExpr(S, move(BaseArg)); 3263 3264 Expr *Base = BaseArg.takeAs<Expr>(); 3265 OwningExprResult Result(*this); 3266 if (Base->getType()->isDependentType() || Name.isDependentName() || 3267 isDependentScopeSpecifier(SS)) { 3268 Result = ActOnDependentMemberExpr(ExprArg(*this, Base), Base->getType(), 3269 IsArrow, OpLoc, 3270 SS, FirstQualifierInScope, 3271 Name, NameLoc, 3272 TemplateArgs); 3273 } else { 3274 LookupResult R(*this, Name, NameLoc, LookupMemberName); 3275 Result = LookupMemberExpr(R, Base, IsArrow, OpLoc, 3276 SS, ObjCImpDecl, TemplateArgs != 0); 3277 3278 if (Result.isInvalid()) { 3279 Owned(Base); 3280 return ExprError(); 3281 } 3282 3283 if (Result.get()) { 3284 // The only way a reference to a destructor can be used is to 3285 // immediately call it, which falls into this case. If the 3286 // next token is not a '(', produce a diagnostic and build the 3287 // call now. 3288 if (!HasTrailingLParen && 3289 Id.getKind() == UnqualifiedId::IK_DestructorName) 3290 return DiagnoseDtorReference(NameLoc, move(Result)); 3291 3292 return move(Result); 3293 } 3294 3295 Result = BuildMemberReferenceExpr(ExprArg(*this, Base), Base->getType(), 3296 OpLoc, IsArrow, SS, FirstQualifierInScope, 3297 R, TemplateArgs); 3298 } 3299 3300 return move(Result); 3301} 3302 3303Sema::OwningExprResult Sema::BuildCXXDefaultArgExpr(SourceLocation CallLoc, 3304 FunctionDecl *FD, 3305 ParmVarDecl *Param) { 3306 if (Param->hasUnparsedDefaultArg()) { 3307 Diag (CallLoc, 3308 diag::err_use_of_default_argument_to_function_declared_later) << 3309 FD << cast<CXXRecordDecl>(FD->getDeclContext())->getDeclName(); 3310 Diag(UnparsedDefaultArgLocs[Param], 3311 diag::note_default_argument_declared_here); 3312 } else { 3313 if (Param->hasUninstantiatedDefaultArg()) { 3314 Expr *UninstExpr = Param->getUninstantiatedDefaultArg(); 3315 3316 // Instantiate the expression. 3317 MultiLevelTemplateArgumentList ArgList 3318 = getTemplateInstantiationArgs(FD, 0, /*RelativeToPrimary=*/true); 3319 3320 std::pair<const TemplateArgument *, unsigned> Innermost 3321 = ArgList.getInnermost(); 3322 InstantiatingTemplate Inst(*this, CallLoc, Param, Innermost.first, 3323 Innermost.second); 3324 3325 OwningExprResult Result = SubstExpr(UninstExpr, ArgList); 3326 if (Result.isInvalid()) 3327 return ExprError(); 3328 3329 // Check the expression as an initializer for the parameter. 3330 InitializedEntity Entity 3331 = InitializedEntity::InitializeParameter(Param); 3332 InitializationKind Kind 3333 = InitializationKind::CreateCopy(Param->getLocation(), 3334 /*FIXME:EqualLoc*/UninstExpr->getSourceRange().getBegin()); 3335 Expr *ResultE = Result.takeAs<Expr>(); 3336 3337 InitializationSequence InitSeq(*this, Entity, Kind, &ResultE, 1); 3338 Result = InitSeq.Perform(*this, Entity, Kind, 3339 MultiExprArg(*this, (void**)&ResultE, 1)); 3340 if (Result.isInvalid()) 3341 return ExprError(); 3342 3343 // Build the default argument expression. 3344 return Owned(CXXDefaultArgExpr::Create(Context, CallLoc, Param, 3345 Result.takeAs<Expr>())); 3346 } 3347 3348 // If the default expression creates temporaries, we need to 3349 // push them to the current stack of expression temporaries so they'll 3350 // be properly destroyed. 3351 // FIXME: We should really be rebuilding the default argument with new 3352 // bound temporaries; see the comment in PR5810. 3353 for (unsigned i = 0, e = Param->getNumDefaultArgTemporaries(); i != e; ++i) 3354 ExprTemporaries.push_back(Param->getDefaultArgTemporary(i)); 3355 } 3356 3357 // We already type-checked the argument, so we know it works. 3358 return Owned(CXXDefaultArgExpr::Create(Context, CallLoc, Param)); 3359} 3360 3361/// ConvertArgumentsForCall - Converts the arguments specified in 3362/// Args/NumArgs to the parameter types of the function FDecl with 3363/// function prototype Proto. Call is the call expression itself, and 3364/// Fn is the function expression. For a C++ member function, this 3365/// routine does not attempt to convert the object argument. Returns 3366/// true if the call is ill-formed. 3367bool 3368Sema::ConvertArgumentsForCall(CallExpr *Call, Expr *Fn, 3369 FunctionDecl *FDecl, 3370 const FunctionProtoType *Proto, 3371 Expr **Args, unsigned NumArgs, 3372 SourceLocation RParenLoc) { 3373 // C99 6.5.2.2p7 - the arguments are implicitly converted, as if by 3374 // assignment, to the types of the corresponding parameter, ... 3375 unsigned NumArgsInProto = Proto->getNumArgs(); 3376 bool Invalid = false; 3377 3378 // If too few arguments are available (and we don't have default 3379 // arguments for the remaining parameters), don't make the call. 3380 if (NumArgs < NumArgsInProto) { 3381 if (!FDecl || NumArgs < FDecl->getMinRequiredArguments()) 3382 return Diag(RParenLoc, diag::err_typecheck_call_too_few_args) 3383 << Fn->getType()->isBlockPointerType() 3384 << NumArgsInProto << NumArgs << Fn->getSourceRange(); 3385 Call->setNumArgs(Context, NumArgsInProto); 3386 } 3387 3388 // If too many are passed and not variadic, error on the extras and drop 3389 // them. 3390 if (NumArgs > NumArgsInProto) { 3391 if (!Proto->isVariadic()) { 3392 Diag(Args[NumArgsInProto]->getLocStart(), 3393 diag::err_typecheck_call_too_many_args) 3394 << Fn->getType()->isBlockPointerType() 3395 << NumArgsInProto << NumArgs << Fn->getSourceRange() 3396 << SourceRange(Args[NumArgsInProto]->getLocStart(), 3397 Args[NumArgs-1]->getLocEnd()); 3398 // This deletes the extra arguments. 3399 Call->setNumArgs(Context, NumArgsInProto); 3400 return true; 3401 } 3402 } 3403 llvm::SmallVector<Expr *, 8> AllArgs; 3404 VariadicCallType CallType = 3405 Proto->isVariadic() ? VariadicFunction : VariadicDoesNotApply; 3406 if (Fn->getType()->isBlockPointerType()) 3407 CallType = VariadicBlock; // Block 3408 else if (isa<MemberExpr>(Fn)) 3409 CallType = VariadicMethod; 3410 Invalid = GatherArgumentsForCall(Call->getSourceRange().getBegin(), FDecl, 3411 Proto, 0, Args, NumArgs, AllArgs, CallType); 3412 if (Invalid) 3413 return true; 3414 unsigned TotalNumArgs = AllArgs.size(); 3415 for (unsigned i = 0; i < TotalNumArgs; ++i) 3416 Call->setArg(i, AllArgs[i]); 3417 3418 return false; 3419} 3420 3421bool Sema::GatherArgumentsForCall(SourceLocation CallLoc, 3422 FunctionDecl *FDecl, 3423 const FunctionProtoType *Proto, 3424 unsigned FirstProtoArg, 3425 Expr **Args, unsigned NumArgs, 3426 llvm::SmallVector<Expr *, 8> &AllArgs, 3427 VariadicCallType CallType) { 3428 unsigned NumArgsInProto = Proto->getNumArgs(); 3429 unsigned NumArgsToCheck = NumArgs; 3430 bool Invalid = false; 3431 if (NumArgs != NumArgsInProto) 3432 // Use default arguments for missing arguments 3433 NumArgsToCheck = NumArgsInProto; 3434 unsigned ArgIx = 0; 3435 // Continue to check argument types (even if we have too few/many args). 3436 for (unsigned i = FirstProtoArg; i != NumArgsToCheck; i++) { 3437 QualType ProtoArgType = Proto->getArgType(i); 3438 3439 Expr *Arg; 3440 if (ArgIx < NumArgs) { 3441 Arg = Args[ArgIx++]; 3442 3443 if (RequireCompleteType(Arg->getSourceRange().getBegin(), 3444 ProtoArgType, 3445 PDiag(diag::err_call_incomplete_argument) 3446 << Arg->getSourceRange())) 3447 return true; 3448 3449 // Pass the argument 3450 ParmVarDecl *Param = 0; 3451 if (FDecl && i < FDecl->getNumParams()) 3452 Param = FDecl->getParamDecl(i); 3453 3454 3455 InitializedEntity Entity = 3456 Param? InitializedEntity::InitializeParameter(Param) 3457 : InitializedEntity::InitializeParameter(ProtoArgType); 3458 OwningExprResult ArgE = PerformCopyInitialization(Entity, 3459 SourceLocation(), 3460 Owned(Arg)); 3461 if (ArgE.isInvalid()) 3462 return true; 3463 3464 Arg = ArgE.takeAs<Expr>(); 3465 } else { 3466 ParmVarDecl *Param = FDecl->getParamDecl(i); 3467 3468 OwningExprResult ArgExpr = 3469 BuildCXXDefaultArgExpr(CallLoc, FDecl, Param); 3470 if (ArgExpr.isInvalid()) 3471 return true; 3472 3473 Arg = ArgExpr.takeAs<Expr>(); 3474 } 3475 AllArgs.push_back(Arg); 3476 } 3477 3478 // If this is a variadic call, handle args passed through "...". 3479 if (CallType != VariadicDoesNotApply) { 3480 // Promote the arguments (C99 6.5.2.2p7). 3481 for (unsigned i = ArgIx; i != NumArgs; ++i) { 3482 Expr *Arg = Args[i]; 3483 Invalid |= DefaultVariadicArgumentPromotion(Arg, CallType, FDecl); 3484 AllArgs.push_back(Arg); 3485 } 3486 } 3487 return Invalid; 3488} 3489 3490/// ActOnCallExpr - Handle a call to Fn with the specified array of arguments. 3491/// This provides the location of the left/right parens and a list of comma 3492/// locations. 3493Action::OwningExprResult 3494Sema::ActOnCallExpr(Scope *S, ExprArg fn, SourceLocation LParenLoc, 3495 MultiExprArg args, 3496 SourceLocation *CommaLocs, SourceLocation RParenLoc) { 3497 unsigned NumArgs = args.size(); 3498 3499 // Since this might be a postfix expression, get rid of ParenListExprs. 3500 fn = MaybeConvertParenListExprToParenExpr(S, move(fn)); 3501 3502 Expr *Fn = fn.takeAs<Expr>(); 3503 Expr **Args = reinterpret_cast<Expr**>(args.release()); 3504 assert(Fn && "no function call expression"); 3505 3506 if (getLangOptions().CPlusPlus) { 3507 // If this is a pseudo-destructor expression, build the call immediately. 3508 if (isa<CXXPseudoDestructorExpr>(Fn)) { 3509 if (NumArgs > 0) { 3510 // Pseudo-destructor calls should not have any arguments. 3511 Diag(Fn->getLocStart(), diag::err_pseudo_dtor_call_with_args) 3512 << FixItHint::CreateRemoval( 3513 SourceRange(Args[0]->getLocStart(), 3514 Args[NumArgs-1]->getLocEnd())); 3515 3516 for (unsigned I = 0; I != NumArgs; ++I) 3517 Args[I]->Destroy(Context); 3518 3519 NumArgs = 0; 3520 } 3521 3522 return Owned(new (Context) CallExpr(Context, Fn, 0, 0, Context.VoidTy, 3523 RParenLoc)); 3524 } 3525 3526 // Determine whether this is a dependent call inside a C++ template, 3527 // in which case we won't do any semantic analysis now. 3528 // FIXME: Will need to cache the results of name lookup (including ADL) in 3529 // Fn. 3530 bool Dependent = false; 3531 if (Fn->isTypeDependent()) 3532 Dependent = true; 3533 else if (Expr::hasAnyTypeDependentArguments(Args, NumArgs)) 3534 Dependent = true; 3535 3536 if (Dependent) 3537 return Owned(new (Context) CallExpr(Context, Fn, Args, NumArgs, 3538 Context.DependentTy, RParenLoc)); 3539 3540 // Determine whether this is a call to an object (C++ [over.call.object]). 3541 if (Fn->getType()->isRecordType()) 3542 return Owned(BuildCallToObjectOfClassType(S, Fn, LParenLoc, Args, NumArgs, 3543 CommaLocs, RParenLoc)); 3544 3545 Expr *NakedFn = Fn->IgnoreParens(); 3546 3547 // Determine whether this is a call to an unresolved member function. 3548 if (UnresolvedMemberExpr *MemE = dyn_cast<UnresolvedMemberExpr>(NakedFn)) { 3549 // If lookup was unresolved but not dependent (i.e. didn't find 3550 // an unresolved using declaration), it has to be an overloaded 3551 // function set, which means it must contain either multiple 3552 // declarations (all methods or method templates) or a single 3553 // method template. 3554 assert((MemE->getNumDecls() > 1) || 3555 isa<FunctionTemplateDecl>( 3556 (*MemE->decls_begin())->getUnderlyingDecl())); 3557 (void)MemE; 3558 3559 return BuildCallToMemberFunction(S, Fn, LParenLoc, Args, NumArgs, 3560 CommaLocs, RParenLoc); 3561 } 3562 3563 // Determine whether this is a call to a member function. 3564 if (MemberExpr *MemExpr = dyn_cast<MemberExpr>(NakedFn)) { 3565 NamedDecl *MemDecl = MemExpr->getMemberDecl(); 3566 if (isa<CXXMethodDecl>(MemDecl)) 3567 return BuildCallToMemberFunction(S, Fn, LParenLoc, Args, NumArgs, 3568 CommaLocs, RParenLoc); 3569 } 3570 3571 // Determine whether this is a call to a pointer-to-member function. 3572 if (BinaryOperator *BO = dyn_cast<BinaryOperator>(NakedFn)) { 3573 if (BO->getOpcode() == BinaryOperator::PtrMemD || 3574 BO->getOpcode() == BinaryOperator::PtrMemI) { 3575 if (const FunctionProtoType *FPT 3576 = BO->getType()->getAs<FunctionProtoType>()) { 3577 QualType ResultTy = FPT->getResultType().getNonReferenceType(); 3578 3579 ExprOwningPtr<CXXMemberCallExpr> 3580 TheCall(this, new (Context) CXXMemberCallExpr(Context, BO, Args, 3581 NumArgs, ResultTy, 3582 RParenLoc)); 3583 3584 if (CheckCallReturnType(FPT->getResultType(), 3585 BO->getRHS()->getSourceRange().getBegin(), 3586 TheCall.get(), 0)) 3587 return ExprError(); 3588 3589 if (ConvertArgumentsForCall(&*TheCall, BO, 0, FPT, Args, NumArgs, 3590 RParenLoc)) 3591 return ExprError(); 3592 3593 return Owned(MaybeBindToTemporary(TheCall.release()).release()); 3594 } 3595 return ExprError(Diag(Fn->getLocStart(), 3596 diag::err_typecheck_call_not_function) 3597 << Fn->getType() << Fn->getSourceRange()); 3598 } 3599 } 3600 } 3601 3602 // If we're directly calling a function, get the appropriate declaration. 3603 // Also, in C++, keep track of whether we should perform argument-dependent 3604 // lookup and whether there were any explicitly-specified template arguments. 3605 3606 Expr *NakedFn = Fn->IgnoreParens(); 3607 if (isa<UnresolvedLookupExpr>(NakedFn)) { 3608 UnresolvedLookupExpr *ULE = cast<UnresolvedLookupExpr>(NakedFn); 3609 return BuildOverloadedCallExpr(S, Fn, ULE, LParenLoc, Args, NumArgs, 3610 CommaLocs, RParenLoc); 3611 } 3612 3613 NamedDecl *NDecl = 0; 3614 if (isa<DeclRefExpr>(NakedFn)) 3615 NDecl = cast<DeclRefExpr>(NakedFn)->getDecl(); 3616 3617 return BuildResolvedCallExpr(Fn, NDecl, LParenLoc, Args, NumArgs, RParenLoc); 3618} 3619 3620/// BuildResolvedCallExpr - Build a call to a resolved expression, 3621/// i.e. an expression not of \p OverloadTy. The expression should 3622/// unary-convert to an expression of function-pointer or 3623/// block-pointer type. 3624/// 3625/// \param NDecl the declaration being called, if available 3626Sema::OwningExprResult 3627Sema::BuildResolvedCallExpr(Expr *Fn, NamedDecl *NDecl, 3628 SourceLocation LParenLoc, 3629 Expr **Args, unsigned NumArgs, 3630 SourceLocation RParenLoc) { 3631 FunctionDecl *FDecl = dyn_cast_or_null<FunctionDecl>(NDecl); 3632 3633 // Promote the function operand. 3634 UsualUnaryConversions(Fn); 3635 3636 // Make the call expr early, before semantic checks. This guarantees cleanup 3637 // of arguments and function on error. 3638 ExprOwningPtr<CallExpr> TheCall(this, new (Context) CallExpr(Context, Fn, 3639 Args, NumArgs, 3640 Context.BoolTy, 3641 RParenLoc)); 3642 3643 const FunctionType *FuncT; 3644 if (!Fn->getType()->isBlockPointerType()) { 3645 // C99 6.5.2.2p1 - "The expression that denotes the called function shall 3646 // have type pointer to function". 3647 const PointerType *PT = Fn->getType()->getAs<PointerType>(); 3648 if (PT == 0) 3649 return ExprError(Diag(LParenLoc, diag::err_typecheck_call_not_function) 3650 << Fn->getType() << Fn->getSourceRange()); 3651 FuncT = PT->getPointeeType()->getAs<FunctionType>(); 3652 } else { // This is a block call. 3653 FuncT = Fn->getType()->getAs<BlockPointerType>()->getPointeeType()-> 3654 getAs<FunctionType>(); 3655 } 3656 if (FuncT == 0) 3657 return ExprError(Diag(LParenLoc, diag::err_typecheck_call_not_function) 3658 << Fn->getType() << Fn->getSourceRange()); 3659 3660 // Check for a valid return type 3661 if (CheckCallReturnType(FuncT->getResultType(), 3662 Fn->getSourceRange().getBegin(), TheCall.get(), 3663 FDecl)) 3664 return ExprError(); 3665 3666 // We know the result type of the call, set it. 3667 TheCall->setType(FuncT->getResultType().getNonReferenceType()); 3668 3669 if (const FunctionProtoType *Proto = dyn_cast<FunctionProtoType>(FuncT)) { 3670 if (ConvertArgumentsForCall(&*TheCall, Fn, FDecl, Proto, Args, NumArgs, 3671 RParenLoc)) 3672 return ExprError(); 3673 } else { 3674 assert(isa<FunctionNoProtoType>(FuncT) && "Unknown FunctionType!"); 3675 3676 if (FDecl) { 3677 // Check if we have too few/too many template arguments, based 3678 // on our knowledge of the function definition. 3679 const FunctionDecl *Def = 0; 3680 if (FDecl->hasBody(Def) && NumArgs != Def->param_size()) { 3681 const FunctionProtoType *Proto = 3682 Def->getType()->getAs<FunctionProtoType>(); 3683 if (!Proto || !(Proto->isVariadic() && NumArgs >= Def->param_size())) { 3684 Diag(RParenLoc, diag::warn_call_wrong_number_of_arguments) 3685 << (NumArgs > Def->param_size()) << FDecl << Fn->getSourceRange(); 3686 } 3687 } 3688 } 3689 3690 // Promote the arguments (C99 6.5.2.2p6). 3691 for (unsigned i = 0; i != NumArgs; i++) { 3692 Expr *Arg = Args[i]; 3693 DefaultArgumentPromotion(Arg); 3694 if (RequireCompleteType(Arg->getSourceRange().getBegin(), 3695 Arg->getType(), 3696 PDiag(diag::err_call_incomplete_argument) 3697 << Arg->getSourceRange())) 3698 return ExprError(); 3699 TheCall->setArg(i, Arg); 3700 } 3701 } 3702 3703 if (CXXMethodDecl *Method = dyn_cast_or_null<CXXMethodDecl>(FDecl)) 3704 if (!Method->isStatic()) 3705 return ExprError(Diag(LParenLoc, diag::err_member_call_without_object) 3706 << Fn->getSourceRange()); 3707 3708 // Check for sentinels 3709 if (NDecl) 3710 DiagnoseSentinelCalls(NDecl, LParenLoc, Args, NumArgs); 3711 3712 // Do special checking on direct calls to functions. 3713 if (FDecl) { 3714 if (CheckFunctionCall(FDecl, TheCall.get())) 3715 return ExprError(); 3716 3717 if (unsigned BuiltinID = FDecl->getBuiltinID()) 3718 return CheckBuiltinFunctionCall(BuiltinID, TheCall.take()); 3719 } else if (NDecl) { 3720 if (CheckBlockCall(NDecl, TheCall.get())) 3721 return ExprError(); 3722 } 3723 3724 return MaybeBindToTemporary(TheCall.take()); 3725} 3726 3727Action::OwningExprResult 3728Sema::ActOnCompoundLiteral(SourceLocation LParenLoc, TypeTy *Ty, 3729 SourceLocation RParenLoc, ExprArg InitExpr) { 3730 assert((Ty != 0) && "ActOnCompoundLiteral(): missing type"); 3731 // FIXME: put back this assert when initializers are worked out. 3732 //assert((InitExpr != 0) && "ActOnCompoundLiteral(): missing expression"); 3733 3734 TypeSourceInfo *TInfo; 3735 QualType literalType = GetTypeFromParser(Ty, &TInfo); 3736 if (!TInfo) 3737 TInfo = Context.getTrivialTypeSourceInfo(literalType); 3738 3739 return BuildCompoundLiteralExpr(LParenLoc, TInfo, RParenLoc, move(InitExpr)); 3740} 3741 3742Action::OwningExprResult 3743Sema::BuildCompoundLiteralExpr(SourceLocation LParenLoc, TypeSourceInfo *TInfo, 3744 SourceLocation RParenLoc, ExprArg InitExpr) { 3745 QualType literalType = TInfo->getType(); 3746 Expr *literalExpr = static_cast<Expr*>(InitExpr.get()); 3747 3748 if (literalType->isArrayType()) { 3749 if (literalType->isVariableArrayType()) 3750 return ExprError(Diag(LParenLoc, diag::err_variable_object_no_init) 3751 << SourceRange(LParenLoc, literalExpr->getSourceRange().getEnd())); 3752 } else if (!literalType->isDependentType() && 3753 RequireCompleteType(LParenLoc, literalType, 3754 PDiag(diag::err_typecheck_decl_incomplete_type) 3755 << SourceRange(LParenLoc, 3756 literalExpr->getSourceRange().getEnd()))) 3757 return ExprError(); 3758 3759 InitializedEntity Entity 3760 = InitializedEntity::InitializeTemporary(literalType); 3761 InitializationKind Kind 3762 = InitializationKind::CreateCast(SourceRange(LParenLoc, RParenLoc), 3763 /*IsCStyleCast=*/true); 3764 InitializationSequence InitSeq(*this, Entity, Kind, &literalExpr, 1); 3765 OwningExprResult Result = InitSeq.Perform(*this, Entity, Kind, 3766 MultiExprArg(*this, (void**)&literalExpr, 1), 3767 &literalType); 3768 if (Result.isInvalid()) 3769 return ExprError(); 3770 InitExpr.release(); 3771 literalExpr = static_cast<Expr*>(Result.get()); 3772 3773 bool isFileScope = getCurFunctionOrMethodDecl() == 0; 3774 if (isFileScope) { // 6.5.2.5p3 3775 if (CheckForConstantInitializer(literalExpr, literalType)) 3776 return ExprError(); 3777 } 3778 3779 Result.release(); 3780 3781 return Owned(new (Context) CompoundLiteralExpr(LParenLoc, TInfo, literalType, 3782 literalExpr, isFileScope)); 3783} 3784 3785Action::OwningExprResult 3786Sema::ActOnInitList(SourceLocation LBraceLoc, MultiExprArg initlist, 3787 SourceLocation RBraceLoc) { 3788 unsigned NumInit = initlist.size(); 3789 Expr **InitList = reinterpret_cast<Expr**>(initlist.release()); 3790 3791 // Semantic analysis for initializers is done by ActOnDeclarator() and 3792 // CheckInitializer() - it requires knowledge of the object being intialized. 3793 3794 InitListExpr *E = new (Context) InitListExpr(Context, LBraceLoc, InitList, 3795 NumInit, RBraceLoc); 3796 E->setType(Context.VoidTy); // FIXME: just a place holder for now. 3797 return Owned(E); 3798} 3799 3800static CastExpr::CastKind getScalarCastKind(ASTContext &Context, 3801 QualType SrcTy, QualType DestTy) { 3802 if (Context.hasSameUnqualifiedType(SrcTy, DestTy)) 3803 return CastExpr::CK_NoOp; 3804 3805 if (SrcTy->hasPointerRepresentation()) { 3806 if (DestTy->hasPointerRepresentation()) 3807 return DestTy->isObjCObjectPointerType() ? 3808 CastExpr::CK_AnyPointerToObjCPointerCast : 3809 CastExpr::CK_BitCast; 3810 if (DestTy->isIntegerType()) 3811 return CastExpr::CK_PointerToIntegral; 3812 } 3813 3814 if (SrcTy->isIntegerType()) { 3815 if (DestTy->isIntegerType()) 3816 return CastExpr::CK_IntegralCast; 3817 if (DestTy->hasPointerRepresentation()) 3818 return CastExpr::CK_IntegralToPointer; 3819 if (DestTy->isRealFloatingType()) 3820 return CastExpr::CK_IntegralToFloating; 3821 } 3822 3823 if (SrcTy->isRealFloatingType()) { 3824 if (DestTy->isRealFloatingType()) 3825 return CastExpr::CK_FloatingCast; 3826 if (DestTy->isIntegerType()) 3827 return CastExpr::CK_FloatingToIntegral; 3828 } 3829 3830 // FIXME: Assert here. 3831 // assert(false && "Unhandled cast combination!"); 3832 return CastExpr::CK_Unknown; 3833} 3834 3835/// CheckCastTypes - Check type constraints for casting between types. 3836bool Sema::CheckCastTypes(SourceRange TyR, QualType castType, Expr *&castExpr, 3837 CastExpr::CastKind& Kind, 3838 CXXBaseSpecifierArray &BasePath, 3839 bool FunctionalStyle) { 3840 if (getLangOptions().CPlusPlus) 3841 return CXXCheckCStyleCast(TyR, castType, castExpr, Kind, BasePath, 3842 FunctionalStyle); 3843 3844 DefaultFunctionArrayLvalueConversion(castExpr); 3845 3846 // C99 6.5.4p2: the cast type needs to be void or scalar and the expression 3847 // type needs to be scalar. 3848 if (castType->isVoidType()) { 3849 // Cast to void allows any expr type. 3850 Kind = CastExpr::CK_ToVoid; 3851 return false; 3852 } 3853 3854 if (!castType->isScalarType() && !castType->isVectorType()) { 3855 if (Context.hasSameUnqualifiedType(castType, castExpr->getType()) && 3856 (castType->isStructureType() || castType->isUnionType())) { 3857 // GCC struct/union extension: allow cast to self. 3858 // FIXME: Check that the cast destination type is complete. 3859 Diag(TyR.getBegin(), diag::ext_typecheck_cast_nonscalar) 3860 << castType << castExpr->getSourceRange(); 3861 Kind = CastExpr::CK_NoOp; 3862 return false; 3863 } 3864 3865 if (castType->isUnionType()) { 3866 // GCC cast to union extension 3867 RecordDecl *RD = castType->getAs<RecordType>()->getDecl(); 3868 RecordDecl::field_iterator Field, FieldEnd; 3869 for (Field = RD->field_begin(), FieldEnd = RD->field_end(); 3870 Field != FieldEnd; ++Field) { 3871 if (Context.hasSameUnqualifiedType(Field->getType(), 3872 castExpr->getType())) { 3873 Diag(TyR.getBegin(), diag::ext_typecheck_cast_to_union) 3874 << castExpr->getSourceRange(); 3875 break; 3876 } 3877 } 3878 if (Field == FieldEnd) 3879 return Diag(TyR.getBegin(), diag::err_typecheck_cast_to_union_no_type) 3880 << castExpr->getType() << castExpr->getSourceRange(); 3881 Kind = CastExpr::CK_ToUnion; 3882 return false; 3883 } 3884 3885 // Reject any other conversions to non-scalar types. 3886 return Diag(TyR.getBegin(), diag::err_typecheck_cond_expect_scalar) 3887 << castType << castExpr->getSourceRange(); 3888 } 3889 3890 if (!castExpr->getType()->isScalarType() && 3891 !castExpr->getType()->isVectorType()) { 3892 return Diag(castExpr->getLocStart(), 3893 diag::err_typecheck_expect_scalar_operand) 3894 << castExpr->getType() << castExpr->getSourceRange(); 3895 } 3896 3897 if (castType->isExtVectorType()) 3898 return CheckExtVectorCast(TyR, castType, castExpr, Kind); 3899 3900 if (castType->isVectorType()) 3901 return CheckVectorCast(TyR, castType, castExpr->getType(), Kind); 3902 if (castExpr->getType()->isVectorType()) 3903 return CheckVectorCast(TyR, castExpr->getType(), castType, Kind); 3904 3905 if (isa<ObjCSelectorExpr>(castExpr)) 3906 return Diag(castExpr->getLocStart(), diag::err_cast_selector_expr); 3907 3908 if (!castType->isArithmeticType()) { 3909 QualType castExprType = castExpr->getType(); 3910 if (!castExprType->isIntegralType(Context) && 3911 castExprType->isArithmeticType()) 3912 return Diag(castExpr->getLocStart(), 3913 diag::err_cast_pointer_from_non_pointer_int) 3914 << castExprType << castExpr->getSourceRange(); 3915 } else if (!castExpr->getType()->isArithmeticType()) { 3916 if (!castType->isIntegralType(Context) && castType->isArithmeticType()) 3917 return Diag(castExpr->getLocStart(), 3918 diag::err_cast_pointer_to_non_pointer_int) 3919 << castType << castExpr->getSourceRange(); 3920 } 3921 3922 Kind = getScalarCastKind(Context, castExpr->getType(), castType); 3923 return false; 3924} 3925 3926bool Sema::CheckVectorCast(SourceRange R, QualType VectorTy, QualType Ty, 3927 CastExpr::CastKind &Kind) { 3928 assert(VectorTy->isVectorType() && "Not a vector type!"); 3929 3930 if (Ty->isVectorType() || Ty->isIntegerType()) { 3931 if (Context.getTypeSize(VectorTy) != Context.getTypeSize(Ty)) 3932 return Diag(R.getBegin(), 3933 Ty->isVectorType() ? 3934 diag::err_invalid_conversion_between_vectors : 3935 diag::err_invalid_conversion_between_vector_and_integer) 3936 << VectorTy << Ty << R; 3937 } else 3938 return Diag(R.getBegin(), 3939 diag::err_invalid_conversion_between_vector_and_scalar) 3940 << VectorTy << Ty << R; 3941 3942 Kind = CastExpr::CK_BitCast; 3943 return false; 3944} 3945 3946bool Sema::CheckExtVectorCast(SourceRange R, QualType DestTy, Expr *&CastExpr, 3947 CastExpr::CastKind &Kind) { 3948 assert(DestTy->isExtVectorType() && "Not an extended vector type!"); 3949 3950 QualType SrcTy = CastExpr->getType(); 3951 3952 // If SrcTy is a VectorType, the total size must match to explicitly cast to 3953 // an ExtVectorType. 3954 if (SrcTy->isVectorType()) { 3955 if (Context.getTypeSize(DestTy) != Context.getTypeSize(SrcTy)) 3956 return Diag(R.getBegin(),diag::err_invalid_conversion_between_ext_vectors) 3957 << DestTy << SrcTy << R; 3958 Kind = CastExpr::CK_BitCast; 3959 return false; 3960 } 3961 3962 // All non-pointer scalars can be cast to ExtVector type. The appropriate 3963 // conversion will take place first from scalar to elt type, and then 3964 // splat from elt type to vector. 3965 if (SrcTy->isPointerType()) 3966 return Diag(R.getBegin(), 3967 diag::err_invalid_conversion_between_vector_and_scalar) 3968 << DestTy << SrcTy << R; 3969 3970 QualType DestElemTy = DestTy->getAs<ExtVectorType>()->getElementType(); 3971 ImpCastExprToType(CastExpr, DestElemTy, 3972 getScalarCastKind(Context, SrcTy, DestElemTy)); 3973 3974 Kind = CastExpr::CK_VectorSplat; 3975 return false; 3976} 3977 3978Action::OwningExprResult 3979Sema::ActOnCastExpr(Scope *S, SourceLocation LParenLoc, TypeTy *Ty, 3980 SourceLocation RParenLoc, ExprArg Op) { 3981 assert((Ty != 0) && (Op.get() != 0) && 3982 "ActOnCastExpr(): missing type or expr"); 3983 3984 TypeSourceInfo *castTInfo; 3985 QualType castType = GetTypeFromParser(Ty, &castTInfo); 3986 if (!castTInfo) 3987 castTInfo = Context.getTrivialTypeSourceInfo(castType); 3988 3989 // If the Expr being casted is a ParenListExpr, handle it specially. 3990 Expr *castExpr = (Expr *)Op.get(); 3991 if (isa<ParenListExpr>(castExpr)) 3992 return ActOnCastOfParenListExpr(S, LParenLoc, RParenLoc, move(Op), 3993 castTInfo); 3994 3995 return BuildCStyleCastExpr(LParenLoc, castTInfo, RParenLoc, move(Op)); 3996} 3997 3998Action::OwningExprResult 3999Sema::BuildCStyleCastExpr(SourceLocation LParenLoc, TypeSourceInfo *Ty, 4000 SourceLocation RParenLoc, ExprArg Op) { 4001 Expr *castExpr = static_cast<Expr*>(Op.get()); 4002 4003 CastExpr::CastKind Kind = CastExpr::CK_Unknown; 4004 CXXBaseSpecifierArray BasePath; 4005 if (CheckCastTypes(SourceRange(LParenLoc, RParenLoc), Ty->getType(), castExpr, 4006 Kind, BasePath)) 4007 return ExprError(); 4008 4009 Op.release(); 4010 return Owned(new (Context) CStyleCastExpr(Ty->getType().getNonReferenceType(), 4011 Kind, castExpr, BasePath, Ty, 4012 LParenLoc, RParenLoc)); 4013} 4014 4015/// This is not an AltiVec-style cast, so turn the ParenListExpr into a sequence 4016/// of comma binary operators. 4017Action::OwningExprResult 4018Sema::MaybeConvertParenListExprToParenExpr(Scope *S, ExprArg EA) { 4019 Expr *expr = EA.takeAs<Expr>(); 4020 ParenListExpr *E = dyn_cast<ParenListExpr>(expr); 4021 if (!E) 4022 return Owned(expr); 4023 4024 OwningExprResult Result(*this, E->getExpr(0)); 4025 4026 for (unsigned i = 1, e = E->getNumExprs(); i != e && !Result.isInvalid(); ++i) 4027 Result = ActOnBinOp(S, E->getExprLoc(), tok::comma, move(Result), 4028 Owned(E->getExpr(i))); 4029 4030 return ActOnParenExpr(E->getLParenLoc(), E->getRParenLoc(), move(Result)); 4031} 4032 4033Action::OwningExprResult 4034Sema::ActOnCastOfParenListExpr(Scope *S, SourceLocation LParenLoc, 4035 SourceLocation RParenLoc, ExprArg Op, 4036 TypeSourceInfo *TInfo) { 4037 ParenListExpr *PE = (ParenListExpr *)Op.get(); 4038 QualType Ty = TInfo->getType(); 4039 bool isAltiVecLiteral = false; 4040 4041 // Check for an altivec literal, 4042 // i.e. all the elements are integer constants. 4043 if (getLangOptions().AltiVec && Ty->isVectorType()) { 4044 if (PE->getNumExprs() == 0) { 4045 Diag(PE->getExprLoc(), diag::err_altivec_empty_initializer); 4046 return ExprError(); 4047 } 4048 if (PE->getNumExprs() == 1) { 4049 if (!PE->getExpr(0)->getType()->isVectorType()) 4050 isAltiVecLiteral = true; 4051 } 4052 else 4053 isAltiVecLiteral = true; 4054 } 4055 4056 // If this is an altivec initializer, '(' type ')' '(' init, ..., init ')' 4057 // then handle it as such. 4058 if (isAltiVecLiteral) { 4059 llvm::SmallVector<Expr *, 8> initExprs; 4060 for (unsigned i = 0, e = PE->getNumExprs(); i != e; ++i) 4061 initExprs.push_back(PE->getExpr(i)); 4062 4063 // FIXME: This means that pretty-printing the final AST will produce curly 4064 // braces instead of the original commas. 4065 Op.release(); 4066 InitListExpr *E = new (Context) InitListExpr(Context, LParenLoc, 4067 &initExprs[0], 4068 initExprs.size(), RParenLoc); 4069 E->setType(Ty); 4070 return BuildCompoundLiteralExpr(LParenLoc, TInfo, RParenLoc, Owned(E)); 4071 } else { 4072 // This is not an AltiVec-style cast, so turn the ParenListExpr into a 4073 // sequence of BinOp comma operators. 4074 Op = MaybeConvertParenListExprToParenExpr(S, move(Op)); 4075 return BuildCStyleCastExpr(LParenLoc, TInfo, RParenLoc, move(Op)); 4076 } 4077} 4078 4079Action::OwningExprResult Sema::ActOnParenOrParenListExpr(SourceLocation L, 4080 SourceLocation R, 4081 MultiExprArg Val, 4082 TypeTy *TypeOfCast) { 4083 unsigned nexprs = Val.size(); 4084 Expr **exprs = reinterpret_cast<Expr**>(Val.release()); 4085 assert((exprs != 0) && "ActOnParenOrParenListExpr() missing expr list"); 4086 Expr *expr; 4087 if (nexprs == 1 && TypeOfCast && !TypeIsVectorType(TypeOfCast)) 4088 expr = new (Context) ParenExpr(L, R, exprs[0]); 4089 else 4090 expr = new (Context) ParenListExpr(Context, L, exprs, nexprs, R); 4091 return Owned(expr); 4092} 4093 4094/// Note that lhs is not null here, even if this is the gnu "x ?: y" extension. 4095/// In that case, lhs = cond. 4096/// C99 6.5.15 4097QualType Sema::CheckConditionalOperands(Expr *&Cond, Expr *&LHS, Expr *&RHS, 4098 SourceLocation QuestionLoc) { 4099 // C++ is sufficiently different to merit its own checker. 4100 if (getLangOptions().CPlusPlus) 4101 return CXXCheckConditionalOperands(Cond, LHS, RHS, QuestionLoc); 4102 4103 UsualUnaryConversions(Cond); 4104 UsualUnaryConversions(LHS); 4105 UsualUnaryConversions(RHS); 4106 QualType CondTy = Cond->getType(); 4107 QualType LHSTy = LHS->getType(); 4108 QualType RHSTy = RHS->getType(); 4109 4110 // first, check the condition. 4111 if (!CondTy->isScalarType()) { // C99 6.5.15p2 4112 Diag(Cond->getLocStart(), diag::err_typecheck_cond_expect_scalar) 4113 << CondTy; 4114 return QualType(); 4115 } 4116 4117 // Now check the two expressions. 4118 if (LHSTy->isVectorType() || RHSTy->isVectorType()) 4119 return CheckVectorOperands(QuestionLoc, LHS, RHS); 4120 4121 // If both operands have arithmetic type, do the usual arithmetic conversions 4122 // to find a common type: C99 6.5.15p3,5. 4123 if (LHSTy->isArithmeticType() && RHSTy->isArithmeticType()) { 4124 UsualArithmeticConversions(LHS, RHS); 4125 return LHS->getType(); 4126 } 4127 4128 // If both operands are the same structure or union type, the result is that 4129 // type. 4130 if (const RecordType *LHSRT = LHSTy->getAs<RecordType>()) { // C99 6.5.15p3 4131 if (const RecordType *RHSRT = RHSTy->getAs<RecordType>()) 4132 if (LHSRT->getDecl() == RHSRT->getDecl()) 4133 // "If both the operands have structure or union type, the result has 4134 // that type." This implies that CV qualifiers are dropped. 4135 return LHSTy.getUnqualifiedType(); 4136 // FIXME: Type of conditional expression must be complete in C mode. 4137 } 4138 4139 // C99 6.5.15p5: "If both operands have void type, the result has void type." 4140 // The following || allows only one side to be void (a GCC-ism). 4141 if (LHSTy->isVoidType() || RHSTy->isVoidType()) { 4142 if (!LHSTy->isVoidType()) 4143 Diag(RHS->getLocStart(), diag::ext_typecheck_cond_one_void) 4144 << RHS->getSourceRange(); 4145 if (!RHSTy->isVoidType()) 4146 Diag(LHS->getLocStart(), diag::ext_typecheck_cond_one_void) 4147 << LHS->getSourceRange(); 4148 ImpCastExprToType(LHS, Context.VoidTy, CastExpr::CK_ToVoid); 4149 ImpCastExprToType(RHS, Context.VoidTy, CastExpr::CK_ToVoid); 4150 return Context.VoidTy; 4151 } 4152 // C99 6.5.15p6 - "if one operand is a null pointer constant, the result has 4153 // the type of the other operand." 4154 if ((LHSTy->isAnyPointerType() || LHSTy->isBlockPointerType()) && 4155 RHS->isNullPointerConstant(Context, Expr::NPC_ValueDependentIsNull)) { 4156 // promote the null to a pointer. 4157 ImpCastExprToType(RHS, LHSTy, CastExpr::CK_Unknown); 4158 return LHSTy; 4159 } 4160 if ((RHSTy->isAnyPointerType() || RHSTy->isBlockPointerType()) && 4161 LHS->isNullPointerConstant(Context, Expr::NPC_ValueDependentIsNull)) { 4162 ImpCastExprToType(LHS, RHSTy, CastExpr::CK_Unknown); 4163 return RHSTy; 4164 } 4165 4166 // All objective-c pointer type analysis is done here. 4167 QualType compositeType = FindCompositeObjCPointerType(LHS, RHS, 4168 QuestionLoc); 4169 if (!compositeType.isNull()) 4170 return compositeType; 4171 4172 4173 // Handle block pointer types. 4174 if (LHSTy->isBlockPointerType() || RHSTy->isBlockPointerType()) { 4175 if (!LHSTy->isBlockPointerType() || !RHSTy->isBlockPointerType()) { 4176 if (LHSTy->isVoidPointerType() || RHSTy->isVoidPointerType()) { 4177 QualType destType = Context.getPointerType(Context.VoidTy); 4178 ImpCastExprToType(LHS, destType, CastExpr::CK_BitCast); 4179 ImpCastExprToType(RHS, destType, CastExpr::CK_BitCast); 4180 return destType; 4181 } 4182 Diag(QuestionLoc, diag::err_typecheck_cond_incompatible_operands) 4183 << LHSTy << RHSTy << LHS->getSourceRange() << RHS->getSourceRange(); 4184 return QualType(); 4185 } 4186 // We have 2 block pointer types. 4187 if (Context.getCanonicalType(LHSTy) == Context.getCanonicalType(RHSTy)) { 4188 // Two identical block pointer types are always compatible. 4189 return LHSTy; 4190 } 4191 // The block pointer types aren't identical, continue checking. 4192 QualType lhptee = LHSTy->getAs<BlockPointerType>()->getPointeeType(); 4193 QualType rhptee = RHSTy->getAs<BlockPointerType>()->getPointeeType(); 4194 4195 if (!Context.typesAreCompatible(lhptee.getUnqualifiedType(), 4196 rhptee.getUnqualifiedType())) { 4197 Diag(QuestionLoc, diag::warn_typecheck_cond_incompatible_pointers) 4198 << LHSTy << RHSTy << LHS->getSourceRange() << RHS->getSourceRange(); 4199 // In this situation, we assume void* type. No especially good 4200 // reason, but this is what gcc does, and we do have to pick 4201 // to get a consistent AST. 4202 QualType incompatTy = Context.getPointerType(Context.VoidTy); 4203 ImpCastExprToType(LHS, incompatTy, CastExpr::CK_BitCast); 4204 ImpCastExprToType(RHS, incompatTy, CastExpr::CK_BitCast); 4205 return incompatTy; 4206 } 4207 // The block pointer types are compatible. 4208 ImpCastExprToType(LHS, LHSTy, CastExpr::CK_BitCast); 4209 ImpCastExprToType(RHS, LHSTy, CastExpr::CK_BitCast); 4210 return LHSTy; 4211 } 4212 4213 // Check constraints for C object pointers types (C99 6.5.15p3,6). 4214 if (LHSTy->isPointerType() && RHSTy->isPointerType()) { 4215 // get the "pointed to" types 4216 QualType lhptee = LHSTy->getAs<PointerType>()->getPointeeType(); 4217 QualType rhptee = RHSTy->getAs<PointerType>()->getPointeeType(); 4218 4219 // ignore qualifiers on void (C99 6.5.15p3, clause 6) 4220 if (lhptee->isVoidType() && rhptee->isIncompleteOrObjectType()) { 4221 // Figure out necessary qualifiers (C99 6.5.15p6) 4222 QualType destPointee 4223 = Context.getQualifiedType(lhptee, rhptee.getQualifiers()); 4224 QualType destType = Context.getPointerType(destPointee); 4225 // Add qualifiers if necessary. 4226 ImpCastExprToType(LHS, destType, CastExpr::CK_NoOp); 4227 // Promote to void*. 4228 ImpCastExprToType(RHS, destType, CastExpr::CK_BitCast); 4229 return destType; 4230 } 4231 if (rhptee->isVoidType() && lhptee->isIncompleteOrObjectType()) { 4232 QualType destPointee 4233 = Context.getQualifiedType(rhptee, lhptee.getQualifiers()); 4234 QualType destType = Context.getPointerType(destPointee); 4235 // Add qualifiers if necessary. 4236 ImpCastExprToType(RHS, destType, CastExpr::CK_NoOp); 4237 // Promote to void*. 4238 ImpCastExprToType(LHS, destType, CastExpr::CK_BitCast); 4239 return destType; 4240 } 4241 4242 if (Context.getCanonicalType(LHSTy) == Context.getCanonicalType(RHSTy)) { 4243 // Two identical pointer types are always compatible. 4244 return LHSTy; 4245 } 4246 if (!Context.typesAreCompatible(lhptee.getUnqualifiedType(), 4247 rhptee.getUnqualifiedType())) { 4248 Diag(QuestionLoc, diag::warn_typecheck_cond_incompatible_pointers) 4249 << LHSTy << RHSTy << LHS->getSourceRange() << RHS->getSourceRange(); 4250 // In this situation, we assume void* type. No especially good 4251 // reason, but this is what gcc does, and we do have to pick 4252 // to get a consistent AST. 4253 QualType incompatTy = Context.getPointerType(Context.VoidTy); 4254 ImpCastExprToType(LHS, incompatTy, CastExpr::CK_BitCast); 4255 ImpCastExprToType(RHS, incompatTy, CastExpr::CK_BitCast); 4256 return incompatTy; 4257 } 4258 // The pointer types are compatible. 4259 // C99 6.5.15p6: If both operands are pointers to compatible types *or* to 4260 // differently qualified versions of compatible types, the result type is 4261 // a pointer to an appropriately qualified version of the *composite* 4262 // type. 4263 // FIXME: Need to calculate the composite type. 4264 // FIXME: Need to add qualifiers 4265 ImpCastExprToType(LHS, LHSTy, CastExpr::CK_BitCast); 4266 ImpCastExprToType(RHS, LHSTy, CastExpr::CK_BitCast); 4267 return LHSTy; 4268 } 4269 4270 // GCC compatibility: soften pointer/integer mismatch. 4271 if (RHSTy->isPointerType() && LHSTy->isIntegerType()) { 4272 Diag(QuestionLoc, diag::warn_typecheck_cond_pointer_integer_mismatch) 4273 << LHSTy << RHSTy << LHS->getSourceRange() << RHS->getSourceRange(); 4274 ImpCastExprToType(LHS, RHSTy, CastExpr::CK_IntegralToPointer); 4275 return RHSTy; 4276 } 4277 if (LHSTy->isPointerType() && RHSTy->isIntegerType()) { 4278 Diag(QuestionLoc, diag::warn_typecheck_cond_pointer_integer_mismatch) 4279 << LHSTy << RHSTy << LHS->getSourceRange() << RHS->getSourceRange(); 4280 ImpCastExprToType(RHS, LHSTy, CastExpr::CK_IntegralToPointer); 4281 return LHSTy; 4282 } 4283 4284 // Otherwise, the operands are not compatible. 4285 Diag(QuestionLoc, diag::err_typecheck_cond_incompatible_operands) 4286 << LHSTy << RHSTy << LHS->getSourceRange() << RHS->getSourceRange(); 4287 return QualType(); 4288} 4289 4290/// FindCompositeObjCPointerType - Helper method to find composite type of 4291/// two objective-c pointer types of the two input expressions. 4292QualType Sema::FindCompositeObjCPointerType(Expr *&LHS, Expr *&RHS, 4293 SourceLocation QuestionLoc) { 4294 QualType LHSTy = LHS->getType(); 4295 QualType RHSTy = RHS->getType(); 4296 4297 // Handle things like Class and struct objc_class*. Here we case the result 4298 // to the pseudo-builtin, because that will be implicitly cast back to the 4299 // redefinition type if an attempt is made to access its fields. 4300 if (LHSTy->isObjCClassType() && 4301 (RHSTy.getDesugaredType() == Context.ObjCClassRedefinitionType)) { 4302 ImpCastExprToType(RHS, LHSTy, CastExpr::CK_BitCast); 4303 return LHSTy; 4304 } 4305 if (RHSTy->isObjCClassType() && 4306 (LHSTy.getDesugaredType() == Context.ObjCClassRedefinitionType)) { 4307 ImpCastExprToType(LHS, RHSTy, CastExpr::CK_BitCast); 4308 return RHSTy; 4309 } 4310 // And the same for struct objc_object* / id 4311 if (LHSTy->isObjCIdType() && 4312 (RHSTy.getDesugaredType() == Context.ObjCIdRedefinitionType)) { 4313 ImpCastExprToType(RHS, LHSTy, CastExpr::CK_BitCast); 4314 return LHSTy; 4315 } 4316 if (RHSTy->isObjCIdType() && 4317 (LHSTy.getDesugaredType() == Context.ObjCIdRedefinitionType)) { 4318 ImpCastExprToType(LHS, RHSTy, CastExpr::CK_BitCast); 4319 return RHSTy; 4320 } 4321 // And the same for struct objc_selector* / SEL 4322 if (Context.isObjCSelType(LHSTy) && 4323 (RHSTy.getDesugaredType() == Context.ObjCSelRedefinitionType)) { 4324 ImpCastExprToType(RHS, LHSTy, CastExpr::CK_BitCast); 4325 return LHSTy; 4326 } 4327 if (Context.isObjCSelType(RHSTy) && 4328 (LHSTy.getDesugaredType() == Context.ObjCSelRedefinitionType)) { 4329 ImpCastExprToType(LHS, RHSTy, CastExpr::CK_BitCast); 4330 return RHSTy; 4331 } 4332 // Check constraints for Objective-C object pointers types. 4333 if (LHSTy->isObjCObjectPointerType() && RHSTy->isObjCObjectPointerType()) { 4334 4335 if (Context.getCanonicalType(LHSTy) == Context.getCanonicalType(RHSTy)) { 4336 // Two identical object pointer types are always compatible. 4337 return LHSTy; 4338 } 4339 const ObjCObjectPointerType *LHSOPT = LHSTy->getAs<ObjCObjectPointerType>(); 4340 const ObjCObjectPointerType *RHSOPT = RHSTy->getAs<ObjCObjectPointerType>(); 4341 QualType compositeType = LHSTy; 4342 4343 // If both operands are interfaces and either operand can be 4344 // assigned to the other, use that type as the composite 4345 // type. This allows 4346 // xxx ? (A*) a : (B*) b 4347 // where B is a subclass of A. 4348 // 4349 // Additionally, as for assignment, if either type is 'id' 4350 // allow silent coercion. Finally, if the types are 4351 // incompatible then make sure to use 'id' as the composite 4352 // type so the result is acceptable for sending messages to. 4353 4354 // FIXME: Consider unifying with 'areComparableObjCPointerTypes'. 4355 // It could return the composite type. 4356 if (Context.canAssignObjCInterfaces(LHSOPT, RHSOPT)) { 4357 compositeType = RHSOPT->isObjCBuiltinType() ? RHSTy : LHSTy; 4358 } else if (Context.canAssignObjCInterfaces(RHSOPT, LHSOPT)) { 4359 compositeType = LHSOPT->isObjCBuiltinType() ? LHSTy : RHSTy; 4360 } else if ((LHSTy->isObjCQualifiedIdType() || 4361 RHSTy->isObjCQualifiedIdType()) && 4362 Context.ObjCQualifiedIdTypesAreCompatible(LHSTy, RHSTy, true)) { 4363 // Need to handle "id<xx>" explicitly. 4364 // GCC allows qualified id and any Objective-C type to devolve to 4365 // id. Currently localizing to here until clear this should be 4366 // part of ObjCQualifiedIdTypesAreCompatible. 4367 compositeType = Context.getObjCIdType(); 4368 } else if (LHSTy->isObjCIdType() || RHSTy->isObjCIdType()) { 4369 compositeType = Context.getObjCIdType(); 4370 } else if (!(compositeType = 4371 Context.areCommonBaseCompatible(LHSOPT, RHSOPT)).isNull()) 4372 ; 4373 else { 4374 Diag(QuestionLoc, diag::ext_typecheck_cond_incompatible_operands) 4375 << LHSTy << RHSTy 4376 << LHS->getSourceRange() << RHS->getSourceRange(); 4377 QualType incompatTy = Context.getObjCIdType(); 4378 ImpCastExprToType(LHS, incompatTy, CastExpr::CK_BitCast); 4379 ImpCastExprToType(RHS, incompatTy, CastExpr::CK_BitCast); 4380 return incompatTy; 4381 } 4382 // The object pointer types are compatible. 4383 ImpCastExprToType(LHS, compositeType, CastExpr::CK_BitCast); 4384 ImpCastExprToType(RHS, compositeType, CastExpr::CK_BitCast); 4385 return compositeType; 4386 } 4387 // Check Objective-C object pointer types and 'void *' 4388 if (LHSTy->isVoidPointerType() && RHSTy->isObjCObjectPointerType()) { 4389 QualType lhptee = LHSTy->getAs<PointerType>()->getPointeeType(); 4390 QualType rhptee = RHSTy->getAs<ObjCObjectPointerType>()->getPointeeType(); 4391 QualType destPointee 4392 = Context.getQualifiedType(lhptee, rhptee.getQualifiers()); 4393 QualType destType = Context.getPointerType(destPointee); 4394 // Add qualifiers if necessary. 4395 ImpCastExprToType(LHS, destType, CastExpr::CK_NoOp); 4396 // Promote to void*. 4397 ImpCastExprToType(RHS, destType, CastExpr::CK_BitCast); 4398 return destType; 4399 } 4400 if (LHSTy->isObjCObjectPointerType() && RHSTy->isVoidPointerType()) { 4401 QualType lhptee = LHSTy->getAs<ObjCObjectPointerType>()->getPointeeType(); 4402 QualType rhptee = RHSTy->getAs<PointerType>()->getPointeeType(); 4403 QualType destPointee 4404 = Context.getQualifiedType(rhptee, lhptee.getQualifiers()); 4405 QualType destType = Context.getPointerType(destPointee); 4406 // Add qualifiers if necessary. 4407 ImpCastExprToType(RHS, destType, CastExpr::CK_NoOp); 4408 // Promote to void*. 4409 ImpCastExprToType(LHS, destType, CastExpr::CK_BitCast); 4410 return destType; 4411 } 4412 return QualType(); 4413} 4414 4415/// ActOnConditionalOp - Parse a ?: operation. Note that 'LHS' may be null 4416/// in the case of a the GNU conditional expr extension. 4417Action::OwningExprResult Sema::ActOnConditionalOp(SourceLocation QuestionLoc, 4418 SourceLocation ColonLoc, 4419 ExprArg Cond, ExprArg LHS, 4420 ExprArg RHS) { 4421 Expr *CondExpr = (Expr *) Cond.get(); 4422 Expr *LHSExpr = (Expr *) LHS.get(), *RHSExpr = (Expr *) RHS.get(); 4423 4424 // If this is the gnu "x ?: y" extension, analyze the types as though the LHS 4425 // was the condition. 4426 bool isLHSNull = LHSExpr == 0; 4427 if (isLHSNull) 4428 LHSExpr = CondExpr; 4429 4430 QualType result = CheckConditionalOperands(CondExpr, LHSExpr, 4431 RHSExpr, QuestionLoc); 4432 if (result.isNull()) 4433 return ExprError(); 4434 4435 Cond.release(); 4436 LHS.release(); 4437 RHS.release(); 4438 return Owned(new (Context) ConditionalOperator(CondExpr, QuestionLoc, 4439 isLHSNull ? 0 : LHSExpr, 4440 ColonLoc, RHSExpr, result)); 4441} 4442 4443// CheckPointerTypesForAssignment - This is a very tricky routine (despite 4444// being closely modeled after the C99 spec:-). The odd characteristic of this 4445// routine is it effectively iqnores the qualifiers on the top level pointee. 4446// This circumvents the usual type rules specified in 6.2.7p1 & 6.7.5.[1-3]. 4447// FIXME: add a couple examples in this comment. 4448Sema::AssignConvertType 4449Sema::CheckPointerTypesForAssignment(QualType lhsType, QualType rhsType) { 4450 QualType lhptee, rhptee; 4451 4452 if ((lhsType->isObjCClassType() && 4453 (rhsType.getDesugaredType() == Context.ObjCClassRedefinitionType)) || 4454 (rhsType->isObjCClassType() && 4455 (lhsType.getDesugaredType() == Context.ObjCClassRedefinitionType))) { 4456 return Compatible; 4457 } 4458 4459 // get the "pointed to" type (ignoring qualifiers at the top level) 4460 lhptee = lhsType->getAs<PointerType>()->getPointeeType(); 4461 rhptee = rhsType->getAs<PointerType>()->getPointeeType(); 4462 4463 // make sure we operate on the canonical type 4464 lhptee = Context.getCanonicalType(lhptee); 4465 rhptee = Context.getCanonicalType(rhptee); 4466 4467 AssignConvertType ConvTy = Compatible; 4468 4469 // C99 6.5.16.1p1: This following citation is common to constraints 4470 // 3 & 4 (below). ...and the type *pointed to* by the left has all the 4471 // qualifiers of the type *pointed to* by the right; 4472 // FIXME: Handle ExtQualType 4473 if (!lhptee.isAtLeastAsQualifiedAs(rhptee)) 4474 ConvTy = CompatiblePointerDiscardsQualifiers; 4475 4476 // C99 6.5.16.1p1 (constraint 4): If one operand is a pointer to an object or 4477 // incomplete type and the other is a pointer to a qualified or unqualified 4478 // version of void... 4479 if (lhptee->isVoidType()) { 4480 if (rhptee->isIncompleteOrObjectType()) 4481 return ConvTy; 4482 4483 // As an extension, we allow cast to/from void* to function pointer. 4484 assert(rhptee->isFunctionType()); 4485 return FunctionVoidPointer; 4486 } 4487 4488 if (rhptee->isVoidType()) { 4489 if (lhptee->isIncompleteOrObjectType()) 4490 return ConvTy; 4491 4492 // As an extension, we allow cast to/from void* to function pointer. 4493 assert(lhptee->isFunctionType()); 4494 return FunctionVoidPointer; 4495 } 4496 // C99 6.5.16.1p1 (constraint 3): both operands are pointers to qualified or 4497 // unqualified versions of compatible types, ... 4498 lhptee = lhptee.getUnqualifiedType(); 4499 rhptee = rhptee.getUnqualifiedType(); 4500 if (!Context.typesAreCompatible(lhptee, rhptee)) { 4501 // Check if the pointee types are compatible ignoring the sign. 4502 // We explicitly check for char so that we catch "char" vs 4503 // "unsigned char" on systems where "char" is unsigned. 4504 if (lhptee->isCharType()) 4505 lhptee = Context.UnsignedCharTy; 4506 else if (lhptee->isSignedIntegerType()) 4507 lhptee = Context.getCorrespondingUnsignedType(lhptee); 4508 4509 if (rhptee->isCharType()) 4510 rhptee = Context.UnsignedCharTy; 4511 else if (rhptee->isSignedIntegerType()) 4512 rhptee = Context.getCorrespondingUnsignedType(rhptee); 4513 4514 if (lhptee == rhptee) { 4515 // Types are compatible ignoring the sign. Qualifier incompatibility 4516 // takes priority over sign incompatibility because the sign 4517 // warning can be disabled. 4518 if (ConvTy != Compatible) 4519 return ConvTy; 4520 return IncompatiblePointerSign; 4521 } 4522 4523 // If we are a multi-level pointer, it's possible that our issue is simply 4524 // one of qualification - e.g. char ** -> const char ** is not allowed. If 4525 // the eventual target type is the same and the pointers have the same 4526 // level of indirection, this must be the issue. 4527 if (lhptee->isPointerType() && rhptee->isPointerType()) { 4528 do { 4529 lhptee = lhptee->getAs<PointerType>()->getPointeeType(); 4530 rhptee = rhptee->getAs<PointerType>()->getPointeeType(); 4531 4532 lhptee = Context.getCanonicalType(lhptee); 4533 rhptee = Context.getCanonicalType(rhptee); 4534 } while (lhptee->isPointerType() && rhptee->isPointerType()); 4535 4536 if (Context.hasSameUnqualifiedType(lhptee, rhptee)) 4537 return IncompatibleNestedPointerQualifiers; 4538 } 4539 4540 // General pointer incompatibility takes priority over qualifiers. 4541 return IncompatiblePointer; 4542 } 4543 return ConvTy; 4544} 4545 4546/// CheckBlockPointerTypesForAssignment - This routine determines whether two 4547/// block pointer types are compatible or whether a block and normal pointer 4548/// are compatible. It is more restrict than comparing two function pointer 4549// types. 4550Sema::AssignConvertType 4551Sema::CheckBlockPointerTypesForAssignment(QualType lhsType, 4552 QualType rhsType) { 4553 QualType lhptee, rhptee; 4554 4555 // get the "pointed to" type (ignoring qualifiers at the top level) 4556 lhptee = lhsType->getAs<BlockPointerType>()->getPointeeType(); 4557 rhptee = rhsType->getAs<BlockPointerType>()->getPointeeType(); 4558 4559 // make sure we operate on the canonical type 4560 lhptee = Context.getCanonicalType(lhptee); 4561 rhptee = Context.getCanonicalType(rhptee); 4562 4563 AssignConvertType ConvTy = Compatible; 4564 4565 // For blocks we enforce that qualifiers are identical. 4566 if (lhptee.getLocalCVRQualifiers() != rhptee.getLocalCVRQualifiers()) 4567 ConvTy = CompatiblePointerDiscardsQualifiers; 4568 4569 if (!getLangOptions().CPlusPlus) { 4570 if (!Context.typesAreBlockPointerCompatible(lhsType, rhsType)) 4571 return IncompatibleBlockPointer; 4572 } 4573 else if (!Context.typesAreCompatible(lhptee, rhptee)) 4574 return IncompatibleBlockPointer; 4575 return ConvTy; 4576} 4577 4578/// CheckObjCPointerTypesForAssignment - Compares two objective-c pointer types 4579/// for assignment compatibility. 4580Sema::AssignConvertType 4581Sema::CheckObjCPointerTypesForAssignment(QualType lhsType, QualType rhsType) { 4582 if (lhsType->isObjCBuiltinType()) { 4583 // Class is not compatible with ObjC object pointers. 4584 if (lhsType->isObjCClassType() && !rhsType->isObjCBuiltinType() && 4585 !rhsType->isObjCQualifiedClassType()) 4586 return IncompatiblePointer; 4587 return Compatible; 4588 } 4589 if (rhsType->isObjCBuiltinType()) { 4590 // Class is not compatible with ObjC object pointers. 4591 if (rhsType->isObjCClassType() && !lhsType->isObjCBuiltinType() && 4592 !lhsType->isObjCQualifiedClassType()) 4593 return IncompatiblePointer; 4594 return Compatible; 4595 } 4596 QualType lhptee = 4597 lhsType->getAs<ObjCObjectPointerType>()->getPointeeType(); 4598 QualType rhptee = 4599 rhsType->getAs<ObjCObjectPointerType>()->getPointeeType(); 4600 // make sure we operate on the canonical type 4601 lhptee = Context.getCanonicalType(lhptee); 4602 rhptee = Context.getCanonicalType(rhptee); 4603 if (!lhptee.isAtLeastAsQualifiedAs(rhptee)) 4604 return CompatiblePointerDiscardsQualifiers; 4605 4606 if (Context.typesAreCompatible(lhsType, rhsType)) 4607 return Compatible; 4608 if (lhsType->isObjCQualifiedIdType() || rhsType->isObjCQualifiedIdType()) 4609 return IncompatibleObjCQualifiedId; 4610 return IncompatiblePointer; 4611} 4612 4613/// CheckAssignmentConstraints (C99 6.5.16) - This routine currently 4614/// has code to accommodate several GCC extensions when type checking 4615/// pointers. Here are some objectionable examples that GCC considers warnings: 4616/// 4617/// int a, *pint; 4618/// short *pshort; 4619/// struct foo *pfoo; 4620/// 4621/// pint = pshort; // warning: assignment from incompatible pointer type 4622/// a = pint; // warning: assignment makes integer from pointer without a cast 4623/// pint = a; // warning: assignment makes pointer from integer without a cast 4624/// pint = pfoo; // warning: assignment from incompatible pointer type 4625/// 4626/// As a result, the code for dealing with pointers is more complex than the 4627/// C99 spec dictates. 4628/// 4629Sema::AssignConvertType 4630Sema::CheckAssignmentConstraints(QualType lhsType, QualType rhsType) { 4631 // Get canonical types. We're not formatting these types, just comparing 4632 // them. 4633 lhsType = Context.getCanonicalType(lhsType).getUnqualifiedType(); 4634 rhsType = Context.getCanonicalType(rhsType).getUnqualifiedType(); 4635 4636 if (lhsType == rhsType) 4637 return Compatible; // Common case: fast path an exact match. 4638 4639 if ((lhsType->isObjCClassType() && 4640 (rhsType.getDesugaredType() == Context.ObjCClassRedefinitionType)) || 4641 (rhsType->isObjCClassType() && 4642 (lhsType.getDesugaredType() == Context.ObjCClassRedefinitionType))) { 4643 return Compatible; 4644 } 4645 4646 // If the left-hand side is a reference type, then we are in a 4647 // (rare!) case where we've allowed the use of references in C, 4648 // e.g., as a parameter type in a built-in function. In this case, 4649 // just make sure that the type referenced is compatible with the 4650 // right-hand side type. The caller is responsible for adjusting 4651 // lhsType so that the resulting expression does not have reference 4652 // type. 4653 if (const ReferenceType *lhsTypeRef = lhsType->getAs<ReferenceType>()) { 4654 if (Context.typesAreCompatible(lhsTypeRef->getPointeeType(), rhsType)) 4655 return Compatible; 4656 return Incompatible; 4657 } 4658 // Allow scalar to ExtVector assignments, and assignments of an ExtVector type 4659 // to the same ExtVector type. 4660 if (lhsType->isExtVectorType()) { 4661 if (rhsType->isExtVectorType()) 4662 return lhsType == rhsType ? Compatible : Incompatible; 4663 if (rhsType->isArithmeticType()) 4664 return Compatible; 4665 } 4666 4667 if (lhsType->isVectorType() || rhsType->isVectorType()) { 4668 // If we are allowing lax vector conversions, and LHS and RHS are both 4669 // vectors, the total size only needs to be the same. This is a bitcast; 4670 // no bits are changed but the result type is different. 4671 if (getLangOptions().LaxVectorConversions && 4672 lhsType->isVectorType() && rhsType->isVectorType()) { 4673 if (Context.getTypeSize(lhsType) == Context.getTypeSize(rhsType)) 4674 return IncompatibleVectors; 4675 } 4676 return Incompatible; 4677 } 4678 4679 if (lhsType->isArithmeticType() && rhsType->isArithmeticType() && 4680 !(getLangOptions().CPlusPlus && lhsType->isEnumeralType())) 4681 return Compatible; 4682 4683 if (isa<PointerType>(lhsType)) { 4684 if (rhsType->isIntegerType()) 4685 return IntToPointer; 4686 4687 if (isa<PointerType>(rhsType)) 4688 return CheckPointerTypesForAssignment(lhsType, rhsType); 4689 4690 // In general, C pointers are not compatible with ObjC object pointers. 4691 if (isa<ObjCObjectPointerType>(rhsType)) { 4692 if (lhsType->isVoidPointerType()) // an exception to the rule. 4693 return Compatible; 4694 return IncompatiblePointer; 4695 } 4696 if (rhsType->getAs<BlockPointerType>()) { 4697 if (lhsType->getAs<PointerType>()->getPointeeType()->isVoidType()) 4698 return Compatible; 4699 4700 // Treat block pointers as objects. 4701 if (getLangOptions().ObjC1 && lhsType->isObjCIdType()) 4702 return Compatible; 4703 } 4704 return Incompatible; 4705 } 4706 4707 if (isa<BlockPointerType>(lhsType)) { 4708 if (rhsType->isIntegerType()) 4709 return IntToBlockPointer; 4710 4711 // Treat block pointers as objects. 4712 if (getLangOptions().ObjC1 && rhsType->isObjCIdType()) 4713 return Compatible; 4714 4715 if (rhsType->isBlockPointerType()) 4716 return CheckBlockPointerTypesForAssignment(lhsType, rhsType); 4717 4718 if (const PointerType *RHSPT = rhsType->getAs<PointerType>()) { 4719 if (RHSPT->getPointeeType()->isVoidType()) 4720 return Compatible; 4721 } 4722 return Incompatible; 4723 } 4724 4725 if (isa<ObjCObjectPointerType>(lhsType)) { 4726 if (rhsType->isIntegerType()) 4727 return IntToPointer; 4728 4729 // In general, C pointers are not compatible with ObjC object pointers. 4730 if (isa<PointerType>(rhsType)) { 4731 if (rhsType->isVoidPointerType()) // an exception to the rule. 4732 return Compatible; 4733 return IncompatiblePointer; 4734 } 4735 if (rhsType->isObjCObjectPointerType()) { 4736 return CheckObjCPointerTypesForAssignment(lhsType, rhsType); 4737 } 4738 if (const PointerType *RHSPT = rhsType->getAs<PointerType>()) { 4739 if (RHSPT->getPointeeType()->isVoidType()) 4740 return Compatible; 4741 } 4742 // Treat block pointers as objects. 4743 if (rhsType->isBlockPointerType()) 4744 return Compatible; 4745 return Incompatible; 4746 } 4747 if (isa<PointerType>(rhsType)) { 4748 // C99 6.5.16.1p1: the left operand is _Bool and the right is a pointer. 4749 if (lhsType == Context.BoolTy) 4750 return Compatible; 4751 4752 if (lhsType->isIntegerType()) 4753 return PointerToInt; 4754 4755 if (isa<PointerType>(lhsType)) 4756 return CheckPointerTypesForAssignment(lhsType, rhsType); 4757 4758 if (isa<BlockPointerType>(lhsType) && 4759 rhsType->getAs<PointerType>()->getPointeeType()->isVoidType()) 4760 return Compatible; 4761 return Incompatible; 4762 } 4763 if (isa<ObjCObjectPointerType>(rhsType)) { 4764 // C99 6.5.16.1p1: the left operand is _Bool and the right is a pointer. 4765 if (lhsType == Context.BoolTy) 4766 return Compatible; 4767 4768 if (lhsType->isIntegerType()) 4769 return PointerToInt; 4770 4771 // In general, C pointers are not compatible with ObjC object pointers. 4772 if (isa<PointerType>(lhsType)) { 4773 if (lhsType->isVoidPointerType()) // an exception to the rule. 4774 return Compatible; 4775 return IncompatiblePointer; 4776 } 4777 if (isa<BlockPointerType>(lhsType) && 4778 rhsType->getAs<PointerType>()->getPointeeType()->isVoidType()) 4779 return Compatible; 4780 return Incompatible; 4781 } 4782 4783 if (isa<TagType>(lhsType) && isa<TagType>(rhsType)) { 4784 if (Context.typesAreCompatible(lhsType, rhsType)) 4785 return Compatible; 4786 } 4787 return Incompatible; 4788} 4789 4790/// \brief Constructs a transparent union from an expression that is 4791/// used to initialize the transparent union. 4792static void ConstructTransparentUnion(ASTContext &C, Expr *&E, 4793 QualType UnionType, FieldDecl *Field) { 4794 // Build an initializer list that designates the appropriate member 4795 // of the transparent union. 4796 InitListExpr *Initializer = new (C) InitListExpr(C, SourceLocation(), 4797 &E, 1, 4798 SourceLocation()); 4799 Initializer->setType(UnionType); 4800 Initializer->setInitializedFieldInUnion(Field); 4801 4802 // Build a compound literal constructing a value of the transparent 4803 // union type from this initializer list. 4804 TypeSourceInfo *unionTInfo = C.getTrivialTypeSourceInfo(UnionType); 4805 E = new (C) CompoundLiteralExpr(SourceLocation(), unionTInfo, UnionType, 4806 Initializer, false); 4807} 4808 4809Sema::AssignConvertType 4810Sema::CheckTransparentUnionArgumentConstraints(QualType ArgType, Expr *&rExpr) { 4811 QualType FromType = rExpr->getType(); 4812 4813 // If the ArgType is a Union type, we want to handle a potential 4814 // transparent_union GCC extension. 4815 const RecordType *UT = ArgType->getAsUnionType(); 4816 if (!UT || !UT->getDecl()->hasAttr<TransparentUnionAttr>()) 4817 return Incompatible; 4818 4819 // The field to initialize within the transparent union. 4820 RecordDecl *UD = UT->getDecl(); 4821 FieldDecl *InitField = 0; 4822 // It's compatible if the expression matches any of the fields. 4823 for (RecordDecl::field_iterator it = UD->field_begin(), 4824 itend = UD->field_end(); 4825 it != itend; ++it) { 4826 if (it->getType()->isPointerType()) { 4827 // If the transparent union contains a pointer type, we allow: 4828 // 1) void pointer 4829 // 2) null pointer constant 4830 if (FromType->isPointerType()) 4831 if (FromType->getAs<PointerType>()->getPointeeType()->isVoidType()) { 4832 ImpCastExprToType(rExpr, it->getType(), CastExpr::CK_BitCast); 4833 InitField = *it; 4834 break; 4835 } 4836 4837 if (rExpr->isNullPointerConstant(Context, 4838 Expr::NPC_ValueDependentIsNull)) { 4839 ImpCastExprToType(rExpr, it->getType(), CastExpr::CK_IntegralToPointer); 4840 InitField = *it; 4841 break; 4842 } 4843 } 4844 4845 if (CheckAssignmentConstraints(it->getType(), rExpr->getType()) 4846 == Compatible) { 4847 InitField = *it; 4848 break; 4849 } 4850 } 4851 4852 if (!InitField) 4853 return Incompatible; 4854 4855 ConstructTransparentUnion(Context, rExpr, ArgType, InitField); 4856 return Compatible; 4857} 4858 4859Sema::AssignConvertType 4860Sema::CheckSingleAssignmentConstraints(QualType lhsType, Expr *&rExpr) { 4861 if (getLangOptions().CPlusPlus) { 4862 if (!lhsType->isRecordType()) { 4863 // C++ 5.17p3: If the left operand is not of class type, the 4864 // expression is implicitly converted (C++ 4) to the 4865 // cv-unqualified type of the left operand. 4866 if (PerformImplicitConversion(rExpr, lhsType.getUnqualifiedType(), 4867 AA_Assigning)) 4868 return Incompatible; 4869 return Compatible; 4870 } 4871 4872 // FIXME: Currently, we fall through and treat C++ classes like C 4873 // structures. 4874 } 4875 4876 // C99 6.5.16.1p1: the left operand is a pointer and the right is 4877 // a null pointer constant. 4878 if ((lhsType->isPointerType() || 4879 lhsType->isObjCObjectPointerType() || 4880 lhsType->isBlockPointerType()) 4881 && rExpr->isNullPointerConstant(Context, 4882 Expr::NPC_ValueDependentIsNull)) { 4883 ImpCastExprToType(rExpr, lhsType, CastExpr::CK_Unknown); 4884 return Compatible; 4885 } 4886 4887 // This check seems unnatural, however it is necessary to ensure the proper 4888 // conversion of functions/arrays. If the conversion were done for all 4889 // DeclExpr's (created by ActOnIdExpression), it would mess up the unary 4890 // expressions that surpress this implicit conversion (&, sizeof). 4891 // 4892 // Suppress this for references: C++ 8.5.3p5. 4893 if (!lhsType->isReferenceType()) 4894 DefaultFunctionArrayLvalueConversion(rExpr); 4895 4896 Sema::AssignConvertType result = 4897 CheckAssignmentConstraints(lhsType, rExpr->getType()); 4898 4899 // C99 6.5.16.1p2: The value of the right operand is converted to the 4900 // type of the assignment expression. 4901 // CheckAssignmentConstraints allows the left-hand side to be a reference, 4902 // so that we can use references in built-in functions even in C. 4903 // The getNonReferenceType() call makes sure that the resulting expression 4904 // does not have reference type. 4905 if (result != Incompatible && rExpr->getType() != lhsType) 4906 ImpCastExprToType(rExpr, lhsType.getNonReferenceType(), 4907 CastExpr::CK_Unknown); 4908 return result; 4909} 4910 4911QualType Sema::InvalidOperands(SourceLocation Loc, Expr *&lex, Expr *&rex) { 4912 Diag(Loc, diag::err_typecheck_invalid_operands) 4913 << lex->getType() << rex->getType() 4914 << lex->getSourceRange() << rex->getSourceRange(); 4915 return QualType(); 4916} 4917 4918QualType Sema::CheckVectorOperands(SourceLocation Loc, Expr *&lex, Expr *&rex) { 4919 // For conversion purposes, we ignore any qualifiers. 4920 // For example, "const float" and "float" are equivalent. 4921 QualType lhsType = 4922 Context.getCanonicalType(lex->getType()).getUnqualifiedType(); 4923 QualType rhsType = 4924 Context.getCanonicalType(rex->getType()).getUnqualifiedType(); 4925 4926 // If the vector types are identical, return. 4927 if (lhsType == rhsType) 4928 return lhsType; 4929 4930 // Handle the case of a vector & extvector type of the same size and element 4931 // type. It would be nice if we only had one vector type someday. 4932 if (getLangOptions().LaxVectorConversions) { 4933 // FIXME: Should we warn here? 4934 if (const VectorType *LV = lhsType->getAs<VectorType>()) { 4935 if (const VectorType *RV = rhsType->getAs<VectorType>()) 4936 if (LV->getElementType() == RV->getElementType() && 4937 LV->getNumElements() == RV->getNumElements()) { 4938 if (lhsType->isExtVectorType()) { 4939 ImpCastExprToType(rex, lhsType, CastExpr::CK_BitCast); 4940 return lhsType; 4941 } 4942 4943 ImpCastExprToType(lex, rhsType, CastExpr::CK_BitCast); 4944 return rhsType; 4945 } 4946 } 4947 } 4948 4949 // Canonicalize the ExtVector to the LHS, remember if we swapped so we can 4950 // swap back (so that we don't reverse the inputs to a subtract, for instance. 4951 bool swapped = false; 4952 if (rhsType->isExtVectorType()) { 4953 swapped = true; 4954 std::swap(rex, lex); 4955 std::swap(rhsType, lhsType); 4956 } 4957 4958 // Handle the case of an ext vector and scalar. 4959 if (const ExtVectorType *LV = lhsType->getAs<ExtVectorType>()) { 4960 QualType EltTy = LV->getElementType(); 4961 if (EltTy->isIntegralType(Context) && rhsType->isIntegralType(Context)) { 4962 if (Context.getIntegerTypeOrder(EltTy, rhsType) >= 0) { 4963 ImpCastExprToType(rex, lhsType, CastExpr::CK_IntegralCast); 4964 if (swapped) std::swap(rex, lex); 4965 return lhsType; 4966 } 4967 } 4968 if (EltTy->isRealFloatingType() && rhsType->isScalarType() && 4969 rhsType->isRealFloatingType()) { 4970 if (Context.getFloatingTypeOrder(EltTy, rhsType) >= 0) { 4971 ImpCastExprToType(rex, lhsType, CastExpr::CK_FloatingCast); 4972 if (swapped) std::swap(rex, lex); 4973 return lhsType; 4974 } 4975 } 4976 } 4977 4978 // Vectors of different size or scalar and non-ext-vector are errors. 4979 Diag(Loc, diag::err_typecheck_vector_not_convertable) 4980 << lex->getType() << rex->getType() 4981 << lex->getSourceRange() << rex->getSourceRange(); 4982 return QualType(); 4983} 4984 4985QualType Sema::CheckMultiplyDivideOperands( 4986 Expr *&lex, Expr *&rex, SourceLocation Loc, bool isCompAssign, bool isDiv) { 4987 if (lex->getType()->isVectorType() || rex->getType()->isVectorType()) 4988 return CheckVectorOperands(Loc, lex, rex); 4989 4990 QualType compType = UsualArithmeticConversions(lex, rex, isCompAssign); 4991 4992 if (!lex->getType()->isArithmeticType() || 4993 !rex->getType()->isArithmeticType()) 4994 return InvalidOperands(Loc, lex, rex); 4995 4996 // Check for division by zero. 4997 if (isDiv && 4998 rex->isNullPointerConstant(Context, Expr::NPC_ValueDependentIsNotNull)) 4999 DiagRuntimeBehavior(Loc, PDiag(diag::warn_division_by_zero) 5000 << rex->getSourceRange()); 5001 5002 return compType; 5003} 5004 5005QualType Sema::CheckRemainderOperands( 5006 Expr *&lex, Expr *&rex, SourceLocation Loc, bool isCompAssign) { 5007 if (lex->getType()->isVectorType() || rex->getType()->isVectorType()) { 5008 if (lex->getType()->isIntegerType() && rex->getType()->isIntegerType()) 5009 return CheckVectorOperands(Loc, lex, rex); 5010 return InvalidOperands(Loc, lex, rex); 5011 } 5012 5013 QualType compType = UsualArithmeticConversions(lex, rex, isCompAssign); 5014 5015 if (!lex->getType()->isIntegerType() || !rex->getType()->isIntegerType()) 5016 return InvalidOperands(Loc, lex, rex); 5017 5018 // Check for remainder by zero. 5019 if (rex->isNullPointerConstant(Context, Expr::NPC_ValueDependentIsNotNull)) 5020 DiagRuntimeBehavior(Loc, PDiag(diag::warn_remainder_by_zero) 5021 << rex->getSourceRange()); 5022 5023 return compType; 5024} 5025 5026QualType Sema::CheckAdditionOperands( // C99 6.5.6 5027 Expr *&lex, Expr *&rex, SourceLocation Loc, QualType* CompLHSTy) { 5028 if (lex->getType()->isVectorType() || rex->getType()->isVectorType()) { 5029 QualType compType = CheckVectorOperands(Loc, lex, rex); 5030 if (CompLHSTy) *CompLHSTy = compType; 5031 return compType; 5032 } 5033 5034 QualType compType = UsualArithmeticConversions(lex, rex, CompLHSTy); 5035 5036 // handle the common case first (both operands are arithmetic). 5037 if (lex->getType()->isArithmeticType() && 5038 rex->getType()->isArithmeticType()) { 5039 if (CompLHSTy) *CompLHSTy = compType; 5040 return compType; 5041 } 5042 5043 // Put any potential pointer into PExp 5044 Expr* PExp = lex, *IExp = rex; 5045 if (IExp->getType()->isAnyPointerType()) 5046 std::swap(PExp, IExp); 5047 5048 if (PExp->getType()->isAnyPointerType()) { 5049 5050 if (IExp->getType()->isIntegerType()) { 5051 QualType PointeeTy = PExp->getType()->getPointeeType(); 5052 5053 // Check for arithmetic on pointers to incomplete types. 5054 if (PointeeTy->isVoidType()) { 5055 if (getLangOptions().CPlusPlus) { 5056 Diag(Loc, diag::err_typecheck_pointer_arith_void_type) 5057 << lex->getSourceRange() << rex->getSourceRange(); 5058 return QualType(); 5059 } 5060 5061 // GNU extension: arithmetic on pointer to void 5062 Diag(Loc, diag::ext_gnu_void_ptr) 5063 << lex->getSourceRange() << rex->getSourceRange(); 5064 } else if (PointeeTy->isFunctionType()) { 5065 if (getLangOptions().CPlusPlus) { 5066 Diag(Loc, diag::err_typecheck_pointer_arith_function_type) 5067 << lex->getType() << lex->getSourceRange(); 5068 return QualType(); 5069 } 5070 5071 // GNU extension: arithmetic on pointer to function 5072 Diag(Loc, diag::ext_gnu_ptr_func_arith) 5073 << lex->getType() << lex->getSourceRange(); 5074 } else { 5075 // Check if we require a complete type. 5076 if (((PExp->getType()->isPointerType() && 5077 !PExp->getType()->isDependentType()) || 5078 PExp->getType()->isObjCObjectPointerType()) && 5079 RequireCompleteType(Loc, PointeeTy, 5080 PDiag(diag::err_typecheck_arithmetic_incomplete_type) 5081 << PExp->getSourceRange() 5082 << PExp->getType())) 5083 return QualType(); 5084 } 5085 // Diagnose bad cases where we step over interface counts. 5086 if (PointeeTy->isObjCObjectType() && LangOpts.ObjCNonFragileABI) { 5087 Diag(Loc, diag::err_arithmetic_nonfragile_interface) 5088 << PointeeTy << PExp->getSourceRange(); 5089 return QualType(); 5090 } 5091 5092 if (CompLHSTy) { 5093 QualType LHSTy = Context.isPromotableBitField(lex); 5094 if (LHSTy.isNull()) { 5095 LHSTy = lex->getType(); 5096 if (LHSTy->isPromotableIntegerType()) 5097 LHSTy = Context.getPromotedIntegerType(LHSTy); 5098 } 5099 *CompLHSTy = LHSTy; 5100 } 5101 return PExp->getType(); 5102 } 5103 } 5104 5105 return InvalidOperands(Loc, lex, rex); 5106} 5107 5108// C99 6.5.6 5109QualType Sema::CheckSubtractionOperands(Expr *&lex, Expr *&rex, 5110 SourceLocation Loc, QualType* CompLHSTy) { 5111 if (lex->getType()->isVectorType() || rex->getType()->isVectorType()) { 5112 QualType compType = CheckVectorOperands(Loc, lex, rex); 5113 if (CompLHSTy) *CompLHSTy = compType; 5114 return compType; 5115 } 5116 5117 QualType compType = UsualArithmeticConversions(lex, rex, CompLHSTy); 5118 5119 // Enforce type constraints: C99 6.5.6p3. 5120 5121 // Handle the common case first (both operands are arithmetic). 5122 if (lex->getType()->isArithmeticType() 5123 && rex->getType()->isArithmeticType()) { 5124 if (CompLHSTy) *CompLHSTy = compType; 5125 return compType; 5126 } 5127 5128 // Either ptr - int or ptr - ptr. 5129 if (lex->getType()->isAnyPointerType()) { 5130 QualType lpointee = lex->getType()->getPointeeType(); 5131 5132 // The LHS must be an completely-defined object type. 5133 5134 bool ComplainAboutVoid = false; 5135 Expr *ComplainAboutFunc = 0; 5136 if (lpointee->isVoidType()) { 5137 if (getLangOptions().CPlusPlus) { 5138 Diag(Loc, diag::err_typecheck_pointer_arith_void_type) 5139 << lex->getSourceRange() << rex->getSourceRange(); 5140 return QualType(); 5141 } 5142 5143 // GNU C extension: arithmetic on pointer to void 5144 ComplainAboutVoid = true; 5145 } else if (lpointee->isFunctionType()) { 5146 if (getLangOptions().CPlusPlus) { 5147 Diag(Loc, diag::err_typecheck_pointer_arith_function_type) 5148 << lex->getType() << lex->getSourceRange(); 5149 return QualType(); 5150 } 5151 5152 // GNU C extension: arithmetic on pointer to function 5153 ComplainAboutFunc = lex; 5154 } else if (!lpointee->isDependentType() && 5155 RequireCompleteType(Loc, lpointee, 5156 PDiag(diag::err_typecheck_sub_ptr_object) 5157 << lex->getSourceRange() 5158 << lex->getType())) 5159 return QualType(); 5160 5161 // Diagnose bad cases where we step over interface counts. 5162 if (lpointee->isObjCObjectType() && LangOpts.ObjCNonFragileABI) { 5163 Diag(Loc, diag::err_arithmetic_nonfragile_interface) 5164 << lpointee << lex->getSourceRange(); 5165 return QualType(); 5166 } 5167 5168 // The result type of a pointer-int computation is the pointer type. 5169 if (rex->getType()->isIntegerType()) { 5170 if (ComplainAboutVoid) 5171 Diag(Loc, diag::ext_gnu_void_ptr) 5172 << lex->getSourceRange() << rex->getSourceRange(); 5173 if (ComplainAboutFunc) 5174 Diag(Loc, diag::ext_gnu_ptr_func_arith) 5175 << ComplainAboutFunc->getType() 5176 << ComplainAboutFunc->getSourceRange(); 5177 5178 if (CompLHSTy) *CompLHSTy = lex->getType(); 5179 return lex->getType(); 5180 } 5181 5182 // Handle pointer-pointer subtractions. 5183 if (const PointerType *RHSPTy = rex->getType()->getAs<PointerType>()) { 5184 QualType rpointee = RHSPTy->getPointeeType(); 5185 5186 // RHS must be a completely-type object type. 5187 // Handle the GNU void* extension. 5188 if (rpointee->isVoidType()) { 5189 if (getLangOptions().CPlusPlus) { 5190 Diag(Loc, diag::err_typecheck_pointer_arith_void_type) 5191 << lex->getSourceRange() << rex->getSourceRange(); 5192 return QualType(); 5193 } 5194 5195 ComplainAboutVoid = true; 5196 } else if (rpointee->isFunctionType()) { 5197 if (getLangOptions().CPlusPlus) { 5198 Diag(Loc, diag::err_typecheck_pointer_arith_function_type) 5199 << rex->getType() << rex->getSourceRange(); 5200 return QualType(); 5201 } 5202 5203 // GNU extension: arithmetic on pointer to function 5204 if (!ComplainAboutFunc) 5205 ComplainAboutFunc = rex; 5206 } else if (!rpointee->isDependentType() && 5207 RequireCompleteType(Loc, rpointee, 5208 PDiag(diag::err_typecheck_sub_ptr_object) 5209 << rex->getSourceRange() 5210 << rex->getType())) 5211 return QualType(); 5212 5213 if (getLangOptions().CPlusPlus) { 5214 // Pointee types must be the same: C++ [expr.add] 5215 if (!Context.hasSameUnqualifiedType(lpointee, rpointee)) { 5216 Diag(Loc, diag::err_typecheck_sub_ptr_compatible) 5217 << lex->getType() << rex->getType() 5218 << lex->getSourceRange() << rex->getSourceRange(); 5219 return QualType(); 5220 } 5221 } else { 5222 // Pointee types must be compatible C99 6.5.6p3 5223 if (!Context.typesAreCompatible( 5224 Context.getCanonicalType(lpointee).getUnqualifiedType(), 5225 Context.getCanonicalType(rpointee).getUnqualifiedType())) { 5226 Diag(Loc, diag::err_typecheck_sub_ptr_compatible) 5227 << lex->getType() << rex->getType() 5228 << lex->getSourceRange() << rex->getSourceRange(); 5229 return QualType(); 5230 } 5231 } 5232 5233 if (ComplainAboutVoid) 5234 Diag(Loc, diag::ext_gnu_void_ptr) 5235 << lex->getSourceRange() << rex->getSourceRange(); 5236 if (ComplainAboutFunc) 5237 Diag(Loc, diag::ext_gnu_ptr_func_arith) 5238 << ComplainAboutFunc->getType() 5239 << ComplainAboutFunc->getSourceRange(); 5240 5241 if (CompLHSTy) *CompLHSTy = lex->getType(); 5242 return Context.getPointerDiffType(); 5243 } 5244 } 5245 5246 return InvalidOperands(Loc, lex, rex); 5247} 5248 5249// C99 6.5.7 5250QualType Sema::CheckShiftOperands(Expr *&lex, Expr *&rex, SourceLocation Loc, 5251 bool isCompAssign) { 5252 // C99 6.5.7p2: Each of the operands shall have integer type. 5253 if (!lex->getType()->isIntegerType() || !rex->getType()->isIntegerType()) 5254 return InvalidOperands(Loc, lex, rex); 5255 5256 // Vector shifts promote their scalar inputs to vector type. 5257 if (lex->getType()->isVectorType() || rex->getType()->isVectorType()) 5258 return CheckVectorOperands(Loc, lex, rex); 5259 5260 // Shifts don't perform usual arithmetic conversions, they just do integer 5261 // promotions on each operand. C99 6.5.7p3 5262 QualType LHSTy = Context.isPromotableBitField(lex); 5263 if (LHSTy.isNull()) { 5264 LHSTy = lex->getType(); 5265 if (LHSTy->isPromotableIntegerType()) 5266 LHSTy = Context.getPromotedIntegerType(LHSTy); 5267 } 5268 if (!isCompAssign) 5269 ImpCastExprToType(lex, LHSTy, CastExpr::CK_IntegralCast); 5270 5271 UsualUnaryConversions(rex); 5272 5273 // Sanity-check shift operands 5274 llvm::APSInt Right; 5275 // Check right/shifter operand 5276 if (!rex->isValueDependent() && 5277 rex->isIntegerConstantExpr(Right, Context)) { 5278 if (Right.isNegative()) 5279 Diag(Loc, diag::warn_shift_negative) << rex->getSourceRange(); 5280 else { 5281 llvm::APInt LeftBits(Right.getBitWidth(), 5282 Context.getTypeSize(lex->getType())); 5283 if (Right.uge(LeftBits)) 5284 Diag(Loc, diag::warn_shift_gt_typewidth) << rex->getSourceRange(); 5285 } 5286 } 5287 5288 // "The type of the result is that of the promoted left operand." 5289 return LHSTy; 5290} 5291 5292// C99 6.5.8, C++ [expr.rel] 5293QualType Sema::CheckCompareOperands(Expr *&lex, Expr *&rex, SourceLocation Loc, 5294 unsigned OpaqueOpc, bool isRelational) { 5295 BinaryOperator::Opcode Opc = (BinaryOperator::Opcode)OpaqueOpc; 5296 5297 // Handle vector comparisons separately. 5298 if (lex->getType()->isVectorType() || rex->getType()->isVectorType()) 5299 return CheckVectorCompareOperands(lex, rex, Loc, isRelational); 5300 5301 QualType lType = lex->getType(); 5302 QualType rType = rex->getType(); 5303 5304 if (!lType->hasFloatingRepresentation() && 5305 !(lType->isBlockPointerType() && isRelational)) { 5306 // For non-floating point types, check for self-comparisons of the form 5307 // x == x, x != x, x < x, etc. These always evaluate to a constant, and 5308 // often indicate logic errors in the program. 5309 // NOTE: Don't warn about comparisons of enum constants. These can arise 5310 // from macro expansions, and are usually quite deliberate. 5311 Expr *LHSStripped = lex->IgnoreParens(); 5312 Expr *RHSStripped = rex->IgnoreParens(); 5313 if (DeclRefExpr* DRL = dyn_cast<DeclRefExpr>(LHSStripped)) 5314 if (DeclRefExpr* DRR = dyn_cast<DeclRefExpr>(RHSStripped)) { 5315 if (DRL->getDecl() == DRR->getDecl() && 5316 !isa<EnumConstantDecl>(DRL->getDecl())) { 5317 DiagRuntimeBehavior(Loc, PDiag(diag::warn_comparison_always) 5318 << 0 // self- 5319 << (Opc == BinaryOperator::EQ 5320 || Opc == BinaryOperator::LE 5321 || Opc == BinaryOperator::GE)); 5322 } else if (lType->isArrayType() && rType->isArrayType() && 5323 !DRL->getDecl()->getType()->isReferenceType() && 5324 !DRR->getDecl()->getType()->isReferenceType()) { 5325 // what is it always going to eval to? 5326 char always_evals_to; 5327 switch(Opc) { 5328 case BinaryOperator::EQ: // e.g. array1 == array2 5329 always_evals_to = 0; // false 5330 break; 5331 case BinaryOperator::NE: // e.g. array1 != array2 5332 always_evals_to = 1; // true 5333 break; 5334 default: 5335 // best we can say is 'a constant' 5336 always_evals_to = 2; // e.g. array1 <= array2 5337 break; 5338 } 5339 DiagRuntimeBehavior(Loc, PDiag(diag::warn_comparison_always) 5340 << 1 // array 5341 << always_evals_to); 5342 } 5343 } 5344 5345 if (isa<CastExpr>(LHSStripped)) 5346 LHSStripped = LHSStripped->IgnoreParenCasts(); 5347 if (isa<CastExpr>(RHSStripped)) 5348 RHSStripped = RHSStripped->IgnoreParenCasts(); 5349 5350 // Warn about comparisons against a string constant (unless the other 5351 // operand is null), the user probably wants strcmp. 5352 Expr *literalString = 0; 5353 Expr *literalStringStripped = 0; 5354 if ((isa<StringLiteral>(LHSStripped) || isa<ObjCEncodeExpr>(LHSStripped)) && 5355 !RHSStripped->isNullPointerConstant(Context, 5356 Expr::NPC_ValueDependentIsNull)) { 5357 literalString = lex; 5358 literalStringStripped = LHSStripped; 5359 } else if ((isa<StringLiteral>(RHSStripped) || 5360 isa<ObjCEncodeExpr>(RHSStripped)) && 5361 !LHSStripped->isNullPointerConstant(Context, 5362 Expr::NPC_ValueDependentIsNull)) { 5363 literalString = rex; 5364 literalStringStripped = RHSStripped; 5365 } 5366 5367 if (literalString) { 5368 std::string resultComparison; 5369 switch (Opc) { 5370 case BinaryOperator::LT: resultComparison = ") < 0"; break; 5371 case BinaryOperator::GT: resultComparison = ") > 0"; break; 5372 case BinaryOperator::LE: resultComparison = ") <= 0"; break; 5373 case BinaryOperator::GE: resultComparison = ") >= 0"; break; 5374 case BinaryOperator::EQ: resultComparison = ") == 0"; break; 5375 case BinaryOperator::NE: resultComparison = ") != 0"; break; 5376 default: assert(false && "Invalid comparison operator"); 5377 } 5378 5379 DiagRuntimeBehavior(Loc, 5380 PDiag(diag::warn_stringcompare) 5381 << isa<ObjCEncodeExpr>(literalStringStripped) 5382 << literalString->getSourceRange()); 5383 } 5384 } 5385 5386 // C99 6.5.8p3 / C99 6.5.9p4 5387 if (lex->getType()->isArithmeticType() && rex->getType()->isArithmeticType()) 5388 UsualArithmeticConversions(lex, rex); 5389 else { 5390 UsualUnaryConversions(lex); 5391 UsualUnaryConversions(rex); 5392 } 5393 5394 lType = lex->getType(); 5395 rType = rex->getType(); 5396 5397 // The result of comparisons is 'bool' in C++, 'int' in C. 5398 QualType ResultTy = getLangOptions().CPlusPlus ? Context.BoolTy:Context.IntTy; 5399 5400 if (isRelational) { 5401 if (lType->isRealType() && rType->isRealType()) 5402 return ResultTy; 5403 } else { 5404 // Check for comparisons of floating point operands using != and ==. 5405 if (lType->hasFloatingRepresentation()) 5406 CheckFloatComparison(Loc,lex,rex); 5407 5408 if (lType->isArithmeticType() && rType->isArithmeticType()) 5409 return ResultTy; 5410 } 5411 5412 bool LHSIsNull = lex->isNullPointerConstant(Context, 5413 Expr::NPC_ValueDependentIsNull); 5414 bool RHSIsNull = rex->isNullPointerConstant(Context, 5415 Expr::NPC_ValueDependentIsNull); 5416 5417 // All of the following pointer-related warnings are GCC extensions, except 5418 // when handling null pointer constants. 5419 if (lType->isPointerType() && rType->isPointerType()) { // C99 6.5.8p2 5420 QualType LCanPointeeTy = 5421 Context.getCanonicalType(lType->getAs<PointerType>()->getPointeeType()); 5422 QualType RCanPointeeTy = 5423 Context.getCanonicalType(rType->getAs<PointerType>()->getPointeeType()); 5424 5425 if (getLangOptions().CPlusPlus) { 5426 if (LCanPointeeTy == RCanPointeeTy) 5427 return ResultTy; 5428 if (!isRelational && 5429 (LCanPointeeTy->isVoidType() || RCanPointeeTy->isVoidType())) { 5430 // Valid unless comparison between non-null pointer and function pointer 5431 // This is a gcc extension compatibility comparison. 5432 // In a SFINAE context, we treat this as a hard error to maintain 5433 // conformance with the C++ standard. 5434 if ((LCanPointeeTy->isFunctionType() || RCanPointeeTy->isFunctionType()) 5435 && !LHSIsNull && !RHSIsNull) { 5436 Diag(Loc, 5437 isSFINAEContext()? 5438 diag::err_typecheck_comparison_of_fptr_to_void 5439 : diag::ext_typecheck_comparison_of_fptr_to_void) 5440 << lType << rType << lex->getSourceRange() << rex->getSourceRange(); 5441 5442 if (isSFINAEContext()) 5443 return QualType(); 5444 5445 ImpCastExprToType(rex, lType, CastExpr::CK_BitCast); 5446 return ResultTy; 5447 } 5448 } 5449 // C++ [expr.rel]p2: 5450 // [...] Pointer conversions (4.10) and qualification 5451 // conversions (4.4) are performed on pointer operands (or on 5452 // a pointer operand and a null pointer constant) to bring 5453 // them to their composite pointer type. [...] 5454 // 5455 // C++ [expr.eq]p1 uses the same notion for (in)equality 5456 // comparisons of pointers. 5457 bool NonStandardCompositeType = false; 5458 QualType T = FindCompositePointerType(Loc, lex, rex, 5459 isSFINAEContext()? 0 : &NonStandardCompositeType); 5460 if (T.isNull()) { 5461 Diag(Loc, diag::err_typecheck_comparison_of_distinct_pointers) 5462 << lType << rType << lex->getSourceRange() << rex->getSourceRange(); 5463 return QualType(); 5464 } else if (NonStandardCompositeType) { 5465 Diag(Loc, 5466 diag::ext_typecheck_comparison_of_distinct_pointers_nonstandard) 5467 << lType << rType << T 5468 << lex->getSourceRange() << rex->getSourceRange(); 5469 } 5470 5471 ImpCastExprToType(lex, T, CastExpr::CK_BitCast); 5472 ImpCastExprToType(rex, T, CastExpr::CK_BitCast); 5473 return ResultTy; 5474 } 5475 // C99 6.5.9p2 and C99 6.5.8p2 5476 if (Context.typesAreCompatible(LCanPointeeTy.getUnqualifiedType(), 5477 RCanPointeeTy.getUnqualifiedType())) { 5478 // Valid unless a relational comparison of function pointers 5479 if (isRelational && LCanPointeeTy->isFunctionType()) { 5480 Diag(Loc, diag::ext_typecheck_ordered_comparison_of_function_pointers) 5481 << lType << rType << lex->getSourceRange() << rex->getSourceRange(); 5482 } 5483 } else if (!isRelational && 5484 (LCanPointeeTy->isVoidType() || RCanPointeeTy->isVoidType())) { 5485 // Valid unless comparison between non-null pointer and function pointer 5486 if ((LCanPointeeTy->isFunctionType() || RCanPointeeTy->isFunctionType()) 5487 && !LHSIsNull && !RHSIsNull) { 5488 Diag(Loc, diag::ext_typecheck_comparison_of_fptr_to_void) 5489 << lType << rType << lex->getSourceRange() << rex->getSourceRange(); 5490 } 5491 } else { 5492 // Invalid 5493 Diag(Loc, diag::ext_typecheck_comparison_of_distinct_pointers) 5494 << lType << rType << lex->getSourceRange() << rex->getSourceRange(); 5495 } 5496 if (LCanPointeeTy != RCanPointeeTy) 5497 ImpCastExprToType(rex, lType, CastExpr::CK_BitCast); 5498 return ResultTy; 5499 } 5500 5501 if (getLangOptions().CPlusPlus) { 5502 // Comparison of pointers with null pointer constants and equality 5503 // comparisons of member pointers to null pointer constants. 5504 if (RHSIsNull && 5505 (lType->isPointerType() || 5506 (!isRelational && lType->isMemberPointerType()))) { 5507 ImpCastExprToType(rex, lType, CastExpr::CK_NullToMemberPointer); 5508 return ResultTy; 5509 } 5510 if (LHSIsNull && 5511 (rType->isPointerType() || 5512 (!isRelational && rType->isMemberPointerType()))) { 5513 ImpCastExprToType(lex, rType, CastExpr::CK_NullToMemberPointer); 5514 return ResultTy; 5515 } 5516 5517 // Comparison of member pointers. 5518 if (!isRelational && 5519 lType->isMemberPointerType() && rType->isMemberPointerType()) { 5520 // C++ [expr.eq]p2: 5521 // In addition, pointers to members can be compared, or a pointer to 5522 // member and a null pointer constant. Pointer to member conversions 5523 // (4.11) and qualification conversions (4.4) are performed to bring 5524 // them to a common type. If one operand is a null pointer constant, 5525 // the common type is the type of the other operand. Otherwise, the 5526 // common type is a pointer to member type similar (4.4) to the type 5527 // of one of the operands, with a cv-qualification signature (4.4) 5528 // that is the union of the cv-qualification signatures of the operand 5529 // types. 5530 bool NonStandardCompositeType = false; 5531 QualType T = FindCompositePointerType(Loc, lex, rex, 5532 isSFINAEContext()? 0 : &NonStandardCompositeType); 5533 if (T.isNull()) { 5534 Diag(Loc, diag::err_typecheck_comparison_of_distinct_pointers) 5535 << lType << rType << lex->getSourceRange() << rex->getSourceRange(); 5536 return QualType(); 5537 } else if (NonStandardCompositeType) { 5538 Diag(Loc, 5539 diag::ext_typecheck_comparison_of_distinct_pointers_nonstandard) 5540 << lType << rType << T 5541 << lex->getSourceRange() << rex->getSourceRange(); 5542 } 5543 5544 ImpCastExprToType(lex, T, CastExpr::CK_BitCast); 5545 ImpCastExprToType(rex, T, CastExpr::CK_BitCast); 5546 return ResultTy; 5547 } 5548 5549 // Comparison of nullptr_t with itself. 5550 if (lType->isNullPtrType() && rType->isNullPtrType()) 5551 return ResultTy; 5552 } 5553 5554 // Handle block pointer types. 5555 if (!isRelational && lType->isBlockPointerType() && rType->isBlockPointerType()) { 5556 QualType lpointee = lType->getAs<BlockPointerType>()->getPointeeType(); 5557 QualType rpointee = rType->getAs<BlockPointerType>()->getPointeeType(); 5558 5559 if (!LHSIsNull && !RHSIsNull && 5560 !Context.typesAreCompatible(lpointee, rpointee)) { 5561 Diag(Loc, diag::err_typecheck_comparison_of_distinct_blocks) 5562 << lType << rType << lex->getSourceRange() << rex->getSourceRange(); 5563 } 5564 ImpCastExprToType(rex, lType, CastExpr::CK_BitCast); 5565 return ResultTy; 5566 } 5567 // Allow block pointers to be compared with null pointer constants. 5568 if (!isRelational 5569 && ((lType->isBlockPointerType() && rType->isPointerType()) 5570 || (lType->isPointerType() && rType->isBlockPointerType()))) { 5571 if (!LHSIsNull && !RHSIsNull) { 5572 if (!((rType->isPointerType() && rType->getAs<PointerType>() 5573 ->getPointeeType()->isVoidType()) 5574 || (lType->isPointerType() && lType->getAs<PointerType>() 5575 ->getPointeeType()->isVoidType()))) 5576 Diag(Loc, diag::err_typecheck_comparison_of_distinct_blocks) 5577 << lType << rType << lex->getSourceRange() << rex->getSourceRange(); 5578 } 5579 ImpCastExprToType(rex, lType, CastExpr::CK_BitCast); 5580 return ResultTy; 5581 } 5582 5583 if ((lType->isObjCObjectPointerType() || rType->isObjCObjectPointerType())) { 5584 if (lType->isPointerType() || rType->isPointerType()) { 5585 const PointerType *LPT = lType->getAs<PointerType>(); 5586 const PointerType *RPT = rType->getAs<PointerType>(); 5587 bool LPtrToVoid = LPT ? 5588 Context.getCanonicalType(LPT->getPointeeType())->isVoidType() : false; 5589 bool RPtrToVoid = RPT ? 5590 Context.getCanonicalType(RPT->getPointeeType())->isVoidType() : false; 5591 5592 if (!LPtrToVoid && !RPtrToVoid && 5593 !Context.typesAreCompatible(lType, rType)) { 5594 Diag(Loc, diag::ext_typecheck_comparison_of_distinct_pointers) 5595 << lType << rType << lex->getSourceRange() << rex->getSourceRange(); 5596 } 5597 ImpCastExprToType(rex, lType, CastExpr::CK_BitCast); 5598 return ResultTy; 5599 } 5600 if (lType->isObjCObjectPointerType() && rType->isObjCObjectPointerType()) { 5601 if (!Context.areComparableObjCPointerTypes(lType, rType)) 5602 Diag(Loc, diag::ext_typecheck_comparison_of_distinct_pointers) 5603 << lType << rType << lex->getSourceRange() << rex->getSourceRange(); 5604 ImpCastExprToType(rex, lType, CastExpr::CK_BitCast); 5605 return ResultTy; 5606 } 5607 } 5608 if ((lType->isAnyPointerType() && rType->isIntegerType()) || 5609 (lType->isIntegerType() && rType->isAnyPointerType())) { 5610 unsigned DiagID = 0; 5611 bool isError = false; 5612 if ((LHSIsNull && lType->isIntegerType()) || 5613 (RHSIsNull && rType->isIntegerType())) { 5614 if (isRelational && !getLangOptions().CPlusPlus) 5615 DiagID = diag::ext_typecheck_ordered_comparison_of_pointer_and_zero; 5616 } else if (isRelational && !getLangOptions().CPlusPlus) 5617 DiagID = diag::ext_typecheck_ordered_comparison_of_pointer_integer; 5618 else if (getLangOptions().CPlusPlus) { 5619 DiagID = diag::err_typecheck_comparison_of_pointer_integer; 5620 isError = true; 5621 } else 5622 DiagID = diag::ext_typecheck_comparison_of_pointer_integer; 5623 5624 if (DiagID) { 5625 Diag(Loc, DiagID) 5626 << lType << rType << lex->getSourceRange() << rex->getSourceRange(); 5627 if (isError) 5628 return QualType(); 5629 } 5630 5631 if (lType->isIntegerType()) 5632 ImpCastExprToType(lex, rType, CastExpr::CK_IntegralToPointer); 5633 else 5634 ImpCastExprToType(rex, lType, CastExpr::CK_IntegralToPointer); 5635 return ResultTy; 5636 } 5637 5638 // Handle block pointers. 5639 if (!isRelational && RHSIsNull 5640 && lType->isBlockPointerType() && rType->isIntegerType()) { 5641 ImpCastExprToType(rex, lType, CastExpr::CK_IntegralToPointer); 5642 return ResultTy; 5643 } 5644 if (!isRelational && LHSIsNull 5645 && lType->isIntegerType() && rType->isBlockPointerType()) { 5646 ImpCastExprToType(lex, rType, CastExpr::CK_IntegralToPointer); 5647 return ResultTy; 5648 } 5649 return InvalidOperands(Loc, lex, rex); 5650} 5651 5652/// CheckVectorCompareOperands - vector comparisons are a clang extension that 5653/// operates on extended vector types. Instead of producing an IntTy result, 5654/// like a scalar comparison, a vector comparison produces a vector of integer 5655/// types. 5656QualType Sema::CheckVectorCompareOperands(Expr *&lex, Expr *&rex, 5657 SourceLocation Loc, 5658 bool isRelational) { 5659 // Check to make sure we're operating on vectors of the same type and width, 5660 // Allowing one side to be a scalar of element type. 5661 QualType vType = CheckVectorOperands(Loc, lex, rex); 5662 if (vType.isNull()) 5663 return vType; 5664 5665 QualType lType = lex->getType(); 5666 QualType rType = rex->getType(); 5667 5668 // For non-floating point types, check for self-comparisons of the form 5669 // x == x, x != x, x < x, etc. These always evaluate to a constant, and 5670 // often indicate logic errors in the program. 5671 if (!lType->hasFloatingRepresentation()) { 5672 if (DeclRefExpr* DRL = dyn_cast<DeclRefExpr>(lex->IgnoreParens())) 5673 if (DeclRefExpr* DRR = dyn_cast<DeclRefExpr>(rex->IgnoreParens())) 5674 if (DRL->getDecl() == DRR->getDecl()) 5675 DiagRuntimeBehavior(Loc, 5676 PDiag(diag::warn_comparison_always) 5677 << 0 // self- 5678 << 2 // "a constant" 5679 ); 5680 } 5681 5682 // Check for comparisons of floating point operands using != and ==. 5683 if (!isRelational && lType->hasFloatingRepresentation()) { 5684 assert (rType->hasFloatingRepresentation()); 5685 CheckFloatComparison(Loc,lex,rex); 5686 } 5687 5688 // Return the type for the comparison, which is the same as vector type for 5689 // integer vectors, or an integer type of identical size and number of 5690 // elements for floating point vectors. 5691 if (lType->isIntegerType()) 5692 return lType; 5693 5694 const VectorType *VTy = lType->getAs<VectorType>(); 5695 unsigned TypeSize = Context.getTypeSize(VTy->getElementType()); 5696 if (TypeSize == Context.getTypeSize(Context.IntTy)) 5697 return Context.getExtVectorType(Context.IntTy, VTy->getNumElements()); 5698 if (TypeSize == Context.getTypeSize(Context.LongTy)) 5699 return Context.getExtVectorType(Context.LongTy, VTy->getNumElements()); 5700 5701 assert(TypeSize == Context.getTypeSize(Context.LongLongTy) && 5702 "Unhandled vector element size in vector compare"); 5703 return Context.getExtVectorType(Context.LongLongTy, VTy->getNumElements()); 5704} 5705 5706inline QualType Sema::CheckBitwiseOperands( 5707 Expr *&lex, Expr *&rex, SourceLocation Loc, bool isCompAssign) { 5708 if (lex->getType()->isVectorType() || rex->getType()->isVectorType()) 5709 return CheckVectorOperands(Loc, lex, rex); 5710 5711 QualType compType = UsualArithmeticConversions(lex, rex, isCompAssign); 5712 5713 if (lex->getType()->isIntegerType() && rex->getType()->isIntegerType()) 5714 return compType; 5715 return InvalidOperands(Loc, lex, rex); 5716} 5717 5718inline QualType Sema::CheckLogicalOperands( // C99 6.5.[13,14] 5719 Expr *&lex, Expr *&rex, SourceLocation Loc) { 5720 if (!Context.getLangOptions().CPlusPlus) { 5721 UsualUnaryConversions(lex); 5722 UsualUnaryConversions(rex); 5723 5724 if (!lex->getType()->isScalarType() || !rex->getType()->isScalarType()) 5725 return InvalidOperands(Loc, lex, rex); 5726 5727 return Context.IntTy; 5728 } 5729 5730 // The following is safe because we only use this method for 5731 // non-overloadable operands. 5732 5733 // C++ [expr.log.and]p1 5734 // C++ [expr.log.or]p1 5735 // The operands are both contextually converted to type bool. 5736 if (PerformContextuallyConvertToBool(lex) || 5737 PerformContextuallyConvertToBool(rex)) 5738 return InvalidOperands(Loc, lex, rex); 5739 5740 // C++ [expr.log.and]p2 5741 // C++ [expr.log.or]p2 5742 // The result is a bool. 5743 return Context.BoolTy; 5744} 5745 5746/// IsReadonlyProperty - Verify that otherwise a valid l-value expression 5747/// is a read-only property; return true if so. A readonly property expression 5748/// depends on various declarations and thus must be treated specially. 5749/// 5750static bool IsReadonlyProperty(Expr *E, Sema &S) { 5751 if (E->getStmtClass() == Expr::ObjCPropertyRefExprClass) { 5752 const ObjCPropertyRefExpr* PropExpr = cast<ObjCPropertyRefExpr>(E); 5753 if (ObjCPropertyDecl *PDecl = PropExpr->getProperty()) { 5754 QualType BaseType = PropExpr->getBase()->getType(); 5755 if (const ObjCObjectPointerType *OPT = 5756 BaseType->getAsObjCInterfacePointerType()) 5757 if (ObjCInterfaceDecl *IFace = OPT->getInterfaceDecl()) 5758 if (S.isPropertyReadonly(PDecl, IFace)) 5759 return true; 5760 } 5761 } 5762 return false; 5763} 5764 5765/// CheckForModifiableLvalue - Verify that E is a modifiable lvalue. If not, 5766/// emit an error and return true. If so, return false. 5767static bool CheckForModifiableLvalue(Expr *E, SourceLocation Loc, Sema &S) { 5768 SourceLocation OrigLoc = Loc; 5769 Expr::isModifiableLvalueResult IsLV = E->isModifiableLvalue(S.Context, 5770 &Loc); 5771 if (IsLV == Expr::MLV_Valid && IsReadonlyProperty(E, S)) 5772 IsLV = Expr::MLV_ReadonlyProperty; 5773 if (IsLV == Expr::MLV_Valid) 5774 return false; 5775 5776 unsigned Diag = 0; 5777 bool NeedType = false; 5778 switch (IsLV) { // C99 6.5.16p2 5779 case Expr::MLV_ConstQualified: Diag = diag::err_typecheck_assign_const; break; 5780 case Expr::MLV_ArrayType: 5781 Diag = diag::err_typecheck_array_not_modifiable_lvalue; 5782 NeedType = true; 5783 break; 5784 case Expr::MLV_NotObjectType: 5785 Diag = diag::err_typecheck_non_object_not_modifiable_lvalue; 5786 NeedType = true; 5787 break; 5788 case Expr::MLV_LValueCast: 5789 Diag = diag::err_typecheck_lvalue_casts_not_supported; 5790 break; 5791 case Expr::MLV_Valid: 5792 llvm_unreachable("did not take early return for MLV_Valid"); 5793 case Expr::MLV_InvalidExpression: 5794 case Expr::MLV_MemberFunction: 5795 case Expr::MLV_ClassTemporary: 5796 Diag = diag::err_typecheck_expression_not_modifiable_lvalue; 5797 break; 5798 case Expr::MLV_IncompleteType: 5799 case Expr::MLV_IncompleteVoidType: 5800 return S.RequireCompleteType(Loc, E->getType(), 5801 S.PDiag(diag::err_typecheck_incomplete_type_not_modifiable_lvalue) 5802 << E->getSourceRange()); 5803 case Expr::MLV_DuplicateVectorComponents: 5804 Diag = diag::err_typecheck_duplicate_vector_components_not_mlvalue; 5805 break; 5806 case Expr::MLV_NotBlockQualified: 5807 Diag = diag::err_block_decl_ref_not_modifiable_lvalue; 5808 break; 5809 case Expr::MLV_ReadonlyProperty: 5810 Diag = diag::error_readonly_property_assignment; 5811 break; 5812 case Expr::MLV_NoSetterProperty: 5813 Diag = diag::error_nosetter_property_assignment; 5814 break; 5815 case Expr::MLV_SubObjCPropertySetting: 5816 Diag = diag::error_no_subobject_property_setting; 5817 break; 5818 } 5819 5820 SourceRange Assign; 5821 if (Loc != OrigLoc) 5822 Assign = SourceRange(OrigLoc, OrigLoc); 5823 if (NeedType) 5824 S.Diag(Loc, Diag) << E->getType() << E->getSourceRange() << Assign; 5825 else 5826 S.Diag(Loc, Diag) << E->getSourceRange() << Assign; 5827 return true; 5828} 5829 5830 5831 5832// C99 6.5.16.1 5833QualType Sema::CheckAssignmentOperands(Expr *LHS, Expr *&RHS, 5834 SourceLocation Loc, 5835 QualType CompoundType) { 5836 // Verify that LHS is a modifiable lvalue, and emit error if not. 5837 if (CheckForModifiableLvalue(LHS, Loc, *this)) 5838 return QualType(); 5839 5840 QualType LHSType = LHS->getType(); 5841 QualType RHSType = CompoundType.isNull() ? RHS->getType() : CompoundType; 5842 AssignConvertType ConvTy; 5843 if (CompoundType.isNull()) { 5844 QualType LHSTy(LHSType); 5845 // Simple assignment "x = y". 5846 if (const ObjCImplicitSetterGetterRefExpr *OISGE = 5847 dyn_cast<ObjCImplicitSetterGetterRefExpr>(LHS)) { 5848 // If using property-dot syntax notation for assignment, and there is a 5849 // setter, RHS expression is being passed to the setter argument. So, 5850 // type conversion (and comparison) is RHS to setter's argument type. 5851 if (const ObjCMethodDecl *SetterMD = OISGE->getSetterMethod()) { 5852 ObjCMethodDecl::param_iterator P = SetterMD->param_begin(); 5853 LHSTy = (*P)->getType(); 5854 } 5855 } 5856 5857 ConvTy = CheckSingleAssignmentConstraints(LHSTy, RHS); 5858 // Special case of NSObject attributes on c-style pointer types. 5859 if (ConvTy == IncompatiblePointer && 5860 ((Context.isObjCNSObjectType(LHSType) && 5861 RHSType->isObjCObjectPointerType()) || 5862 (Context.isObjCNSObjectType(RHSType) && 5863 LHSType->isObjCObjectPointerType()))) 5864 ConvTy = Compatible; 5865 5866 // If the RHS is a unary plus or minus, check to see if they = and + are 5867 // right next to each other. If so, the user may have typo'd "x =+ 4" 5868 // instead of "x += 4". 5869 Expr *RHSCheck = RHS; 5870 if (ImplicitCastExpr *ICE = dyn_cast<ImplicitCastExpr>(RHSCheck)) 5871 RHSCheck = ICE->getSubExpr(); 5872 if (UnaryOperator *UO = dyn_cast<UnaryOperator>(RHSCheck)) { 5873 if ((UO->getOpcode() == UnaryOperator::Plus || 5874 UO->getOpcode() == UnaryOperator::Minus) && 5875 Loc.isFileID() && UO->getOperatorLoc().isFileID() && 5876 // Only if the two operators are exactly adjacent. 5877 Loc.getFileLocWithOffset(1) == UO->getOperatorLoc() && 5878 // And there is a space or other character before the subexpr of the 5879 // unary +/-. We don't want to warn on "x=-1". 5880 Loc.getFileLocWithOffset(2) != UO->getSubExpr()->getLocStart() && 5881 UO->getSubExpr()->getLocStart().isFileID()) { 5882 Diag(Loc, diag::warn_not_compound_assign) 5883 << (UO->getOpcode() == UnaryOperator::Plus ? "+" : "-") 5884 << SourceRange(UO->getOperatorLoc(), UO->getOperatorLoc()); 5885 } 5886 } 5887 } else { 5888 // Compound assignment "x += y" 5889 ConvTy = CheckAssignmentConstraints(LHSType, RHSType); 5890 } 5891 5892 if (DiagnoseAssignmentResult(ConvTy, Loc, LHSType, RHSType, 5893 RHS, AA_Assigning)) 5894 return QualType(); 5895 5896 5897 // Check to see if the destination operand is a dereferenced null pointer. If 5898 // so, and if not volatile-qualified, this is undefined behavior that the 5899 // optimizer will delete, so warn about it. People sometimes try to use this 5900 // to get a deterministic trap and are surprised by clang's behavior. This 5901 // only handles the pattern "*null = whatever", which is a very syntactic 5902 // check. 5903 if (UnaryOperator *UO = dyn_cast<UnaryOperator>(LHS->IgnoreParenCasts())) 5904 if (UO->getOpcode() == UnaryOperator::Deref && 5905 UO->getSubExpr()->IgnoreParenCasts()-> 5906 isNullPointerConstant(Context, Expr::NPC_ValueDependentIsNotNull) && 5907 !UO->getType().isVolatileQualified()) { 5908 Diag(UO->getOperatorLoc(), diag::warn_indirection_through_null) 5909 << UO->getSubExpr()->getSourceRange(); 5910 Diag(UO->getOperatorLoc(), diag::note_indirection_through_null); 5911 } 5912 5913 // C99 6.5.16p3: The type of an assignment expression is the type of the 5914 // left operand unless the left operand has qualified type, in which case 5915 // it is the unqualified version of the type of the left operand. 5916 // C99 6.5.16.1p2: In simple assignment, the value of the right operand 5917 // is converted to the type of the assignment expression (above). 5918 // C++ 5.17p1: the type of the assignment expression is that of its left 5919 // operand. 5920 return LHSType.getUnqualifiedType(); 5921} 5922 5923// C99 6.5.17 5924QualType Sema::CheckCommaOperands(Expr *LHS, Expr *&RHS, SourceLocation Loc) { 5925 DiagnoseUnusedExprResult(LHS); 5926 5927 // Comma performs lvalue conversion (C99 6.3.2.1), but not unary conversions. 5928 // C++ does not perform this conversion (C++ [expr.comma]p1). 5929 if (!getLangOptions().CPlusPlus) 5930 DefaultFunctionArrayLvalueConversion(RHS); 5931 5932 // FIXME: Check that RHS type is complete in C mode (it's legal for it to be 5933 // incomplete in C++). 5934 5935 return RHS->getType(); 5936} 5937 5938/// CheckIncrementDecrementOperand - unlike most "Check" methods, this routine 5939/// doesn't need to call UsualUnaryConversions or UsualArithmeticConversions. 5940QualType Sema::CheckIncrementDecrementOperand(Expr *Op, SourceLocation OpLoc, 5941 bool isInc, bool isPrefix) { 5942 if (Op->isTypeDependent()) 5943 return Context.DependentTy; 5944 5945 QualType ResType = Op->getType(); 5946 assert(!ResType.isNull() && "no type for increment/decrement expression"); 5947 5948 if (getLangOptions().CPlusPlus && ResType->isBooleanType()) { 5949 // Decrement of bool is not allowed. 5950 if (!isInc) { 5951 Diag(OpLoc, diag::err_decrement_bool) << Op->getSourceRange(); 5952 return QualType(); 5953 } 5954 // Increment of bool sets it to true, but is deprecated. 5955 Diag(OpLoc, diag::warn_increment_bool) << Op->getSourceRange(); 5956 } else if (ResType->isRealType()) { 5957 // OK! 5958 } else if (ResType->isAnyPointerType()) { 5959 QualType PointeeTy = ResType->getPointeeType(); 5960 5961 // C99 6.5.2.4p2, 6.5.6p2 5962 if (PointeeTy->isVoidType()) { 5963 if (getLangOptions().CPlusPlus) { 5964 Diag(OpLoc, diag::err_typecheck_pointer_arith_void_type) 5965 << Op->getSourceRange(); 5966 return QualType(); 5967 } 5968 5969 // Pointer to void is a GNU extension in C. 5970 Diag(OpLoc, diag::ext_gnu_void_ptr) << Op->getSourceRange(); 5971 } else if (PointeeTy->isFunctionType()) { 5972 if (getLangOptions().CPlusPlus) { 5973 Diag(OpLoc, diag::err_typecheck_pointer_arith_function_type) 5974 << Op->getType() << Op->getSourceRange(); 5975 return QualType(); 5976 } 5977 5978 Diag(OpLoc, diag::ext_gnu_ptr_func_arith) 5979 << ResType << Op->getSourceRange(); 5980 } else if (RequireCompleteType(OpLoc, PointeeTy, 5981 PDiag(diag::err_typecheck_arithmetic_incomplete_type) 5982 << Op->getSourceRange() 5983 << ResType)) 5984 return QualType(); 5985 // Diagnose bad cases where we step over interface counts. 5986 else if (PointeeTy->isObjCObjectType() && LangOpts.ObjCNonFragileABI) { 5987 Diag(OpLoc, diag::err_arithmetic_nonfragile_interface) 5988 << PointeeTy << Op->getSourceRange(); 5989 return QualType(); 5990 } 5991 } else if (ResType->isAnyComplexType()) { 5992 // C99 does not support ++/-- on complex types, we allow as an extension. 5993 Diag(OpLoc, diag::ext_integer_increment_complex) 5994 << ResType << Op->getSourceRange(); 5995 } else { 5996 Diag(OpLoc, diag::err_typecheck_illegal_increment_decrement) 5997 << ResType << int(isInc) << Op->getSourceRange(); 5998 return QualType(); 5999 } 6000 // At this point, we know we have a real, complex or pointer type. 6001 // Now make sure the operand is a modifiable lvalue. 6002 if (CheckForModifiableLvalue(Op, OpLoc, *this)) 6003 return QualType(); 6004 // In C++, a prefix increment is the same type as the operand. Otherwise 6005 // (in C or with postfix), the increment is the unqualified type of the 6006 // operand. 6007 return isPrefix && getLangOptions().CPlusPlus 6008 ? ResType : ResType.getUnqualifiedType(); 6009} 6010 6011/// getPrimaryDecl - Helper function for CheckAddressOfOperand(). 6012/// This routine allows us to typecheck complex/recursive expressions 6013/// where the declaration is needed for type checking. We only need to 6014/// handle cases when the expression references a function designator 6015/// or is an lvalue. Here are some examples: 6016/// - &(x) => x 6017/// - &*****f => f for f a function designator. 6018/// - &s.xx => s 6019/// - &s.zz[1].yy -> s, if zz is an array 6020/// - *(x + 1) -> x, if x is an array 6021/// - &"123"[2] -> 0 6022/// - & __real__ x -> x 6023static NamedDecl *getPrimaryDecl(Expr *E) { 6024 switch (E->getStmtClass()) { 6025 case Stmt::DeclRefExprClass: 6026 return cast<DeclRefExpr>(E)->getDecl(); 6027 case Stmt::MemberExprClass: 6028 // If this is an arrow operator, the address is an offset from 6029 // the base's value, so the object the base refers to is 6030 // irrelevant. 6031 if (cast<MemberExpr>(E)->isArrow()) 6032 return 0; 6033 // Otherwise, the expression refers to a part of the base 6034 return getPrimaryDecl(cast<MemberExpr>(E)->getBase()); 6035 case Stmt::ArraySubscriptExprClass: { 6036 // FIXME: This code shouldn't be necessary! We should catch the implicit 6037 // promotion of register arrays earlier. 6038 Expr* Base = cast<ArraySubscriptExpr>(E)->getBase(); 6039 if (ImplicitCastExpr* ICE = dyn_cast<ImplicitCastExpr>(Base)) { 6040 if (ICE->getSubExpr()->getType()->isArrayType()) 6041 return getPrimaryDecl(ICE->getSubExpr()); 6042 } 6043 return 0; 6044 } 6045 case Stmt::UnaryOperatorClass: { 6046 UnaryOperator *UO = cast<UnaryOperator>(E); 6047 6048 switch(UO->getOpcode()) { 6049 case UnaryOperator::Real: 6050 case UnaryOperator::Imag: 6051 case UnaryOperator::Extension: 6052 return getPrimaryDecl(UO->getSubExpr()); 6053 default: 6054 return 0; 6055 } 6056 } 6057 case Stmt::ParenExprClass: 6058 return getPrimaryDecl(cast<ParenExpr>(E)->getSubExpr()); 6059 case Stmt::ImplicitCastExprClass: 6060 // If the result of an implicit cast is an l-value, we care about 6061 // the sub-expression; otherwise, the result here doesn't matter. 6062 return getPrimaryDecl(cast<ImplicitCastExpr>(E)->getSubExpr()); 6063 default: 6064 return 0; 6065 } 6066} 6067 6068/// CheckAddressOfOperand - The operand of & must be either a function 6069/// designator or an lvalue designating an object. If it is an lvalue, the 6070/// object cannot be declared with storage class register or be a bit field. 6071/// Note: The usual conversions are *not* applied to the operand of the & 6072/// operator (C99 6.3.2.1p[2-4]), and its result is never an lvalue. 6073/// In C++, the operand might be an overloaded function name, in which case 6074/// we allow the '&' but retain the overloaded-function type. 6075QualType Sema::CheckAddressOfOperand(Expr *op, SourceLocation OpLoc) { 6076 // Make sure to ignore parentheses in subsequent checks 6077 op = op->IgnoreParens(); 6078 6079 if (op->isTypeDependent()) 6080 return Context.DependentTy; 6081 6082 if (getLangOptions().C99) { 6083 // Implement C99-only parts of addressof rules. 6084 if (UnaryOperator* uOp = dyn_cast<UnaryOperator>(op)) { 6085 if (uOp->getOpcode() == UnaryOperator::Deref) 6086 // Per C99 6.5.3.2, the address of a deref always returns a valid result 6087 // (assuming the deref expression is valid). 6088 return uOp->getSubExpr()->getType(); 6089 } 6090 // Technically, there should be a check for array subscript 6091 // expressions here, but the result of one is always an lvalue anyway. 6092 } 6093 NamedDecl *dcl = getPrimaryDecl(op); 6094 Expr::isLvalueResult lval = op->isLvalue(Context); 6095 6096 MemberExpr *ME = dyn_cast<MemberExpr>(op); 6097 if (lval == Expr::LV_MemberFunction && ME && 6098 isa<CXXMethodDecl>(ME->getMemberDecl())) { 6099 ValueDecl *dcl = cast<MemberExpr>(op)->getMemberDecl(); 6100 // &f where f is a member of the current object, or &o.f, or &p->f 6101 // All these are not allowed, and we need to catch them before the dcl 6102 // branch of the if, below. 6103 Diag(OpLoc, diag::err_unqualified_pointer_member_function) 6104 << dcl; 6105 // FIXME: Improve this diagnostic and provide a fixit. 6106 6107 // Now recover by acting as if the function had been accessed qualified. 6108 return Context.getMemberPointerType(op->getType(), 6109 Context.getTypeDeclType(cast<RecordDecl>(dcl->getDeclContext())) 6110 .getTypePtr()); 6111 } 6112 6113 if (lval == Expr::LV_ClassTemporary) { 6114 Diag(OpLoc, isSFINAEContext()? diag::err_typecheck_addrof_class_temporary 6115 : diag::ext_typecheck_addrof_class_temporary) 6116 << op->getType() << op->getSourceRange(); 6117 if (isSFINAEContext()) 6118 return QualType(); 6119 } else if (isa<ObjCSelectorExpr>(op)) 6120 return Context.getPointerType(op->getType()); 6121 else if (lval != Expr::LV_Valid && lval != Expr::LV_IncompleteVoidType) { 6122 // C99 6.5.3.2p1 6123 // The operand must be either an l-value or a function designator 6124 if (!op->getType()->isFunctionType()) { 6125 // FIXME: emit more specific diag... 6126 Diag(OpLoc, diag::err_typecheck_invalid_lvalue_addrof) 6127 << op->getSourceRange(); 6128 return QualType(); 6129 } 6130 } else if (op->getBitField()) { // C99 6.5.3.2p1 6131 // The operand cannot be a bit-field 6132 Diag(OpLoc, diag::err_typecheck_address_of) 6133 << "bit-field" << op->getSourceRange(); 6134 return QualType(); 6135 } else if (op->refersToVectorElement()) { 6136 // The operand cannot be an element of a vector 6137 Diag(OpLoc, diag::err_typecheck_address_of) 6138 << "vector element" << op->getSourceRange(); 6139 return QualType(); 6140 } else if (isa<ObjCPropertyRefExpr>(op)) { 6141 // cannot take address of a property expression. 6142 Diag(OpLoc, diag::err_typecheck_address_of) 6143 << "property expression" << op->getSourceRange(); 6144 return QualType(); 6145 } else if (ConditionalOperator *CO = dyn_cast<ConditionalOperator>(op)) { 6146 // FIXME: Can LHS ever be null here? 6147 if (!CheckAddressOfOperand(CO->getTrueExpr(), OpLoc).isNull()) 6148 return CheckAddressOfOperand(CO->getFalseExpr(), OpLoc); 6149 } else if (isa<UnresolvedLookupExpr>(op)) { 6150 return Context.OverloadTy; 6151 } else if (dcl) { // C99 6.5.3.2p1 6152 // We have an lvalue with a decl. Make sure the decl is not declared 6153 // with the register storage-class specifier. 6154 if (const VarDecl *vd = dyn_cast<VarDecl>(dcl)) { 6155 if (vd->getStorageClass() == VarDecl::Register) { 6156 Diag(OpLoc, diag::err_typecheck_address_of) 6157 << "register variable" << op->getSourceRange(); 6158 return QualType(); 6159 } 6160 } else if (isa<FunctionTemplateDecl>(dcl)) { 6161 return Context.OverloadTy; 6162 } else if (FieldDecl *FD = dyn_cast<FieldDecl>(dcl)) { 6163 // Okay: we can take the address of a field. 6164 // Could be a pointer to member, though, if there is an explicit 6165 // scope qualifier for the class. 6166 if (isa<DeclRefExpr>(op) && cast<DeclRefExpr>(op)->getQualifier()) { 6167 DeclContext *Ctx = dcl->getDeclContext(); 6168 if (Ctx && Ctx->isRecord()) { 6169 if (FD->getType()->isReferenceType()) { 6170 Diag(OpLoc, 6171 diag::err_cannot_form_pointer_to_member_of_reference_type) 6172 << FD->getDeclName() << FD->getType(); 6173 return QualType(); 6174 } 6175 6176 return Context.getMemberPointerType(op->getType(), 6177 Context.getTypeDeclType(cast<RecordDecl>(Ctx)).getTypePtr()); 6178 } 6179 } 6180 } else if (CXXMethodDecl *MD = dyn_cast<CXXMethodDecl>(dcl)) { 6181 // Okay: we can take the address of a function. 6182 // As above. 6183 if (isa<DeclRefExpr>(op) && cast<DeclRefExpr>(op)->getQualifier() && 6184 MD->isInstance()) 6185 return Context.getMemberPointerType(op->getType(), 6186 Context.getTypeDeclType(MD->getParent()).getTypePtr()); 6187 } else if (!isa<FunctionDecl>(dcl)) 6188 assert(0 && "Unknown/unexpected decl type"); 6189 } 6190 6191 if (lval == Expr::LV_IncompleteVoidType) { 6192 // Taking the address of a void variable is technically illegal, but we 6193 // allow it in cases which are otherwise valid. 6194 // Example: "extern void x; void* y = &x;". 6195 Diag(OpLoc, diag::ext_typecheck_addrof_void) << op->getSourceRange(); 6196 } 6197 6198 // If the operand has type "type", the result has type "pointer to type". 6199 return Context.getPointerType(op->getType()); 6200} 6201 6202/// CheckIndirectionOperand - Type check unary indirection (prefix '*'). 6203QualType Sema::CheckIndirectionOperand(Expr *Op, SourceLocation OpLoc) { 6204 if (Op->isTypeDependent()) 6205 return Context.DependentTy; 6206 6207 UsualUnaryConversions(Op); 6208 QualType OpTy = Op->getType(); 6209 QualType Result; 6210 6211 // Note that per both C89 and C99, indirection is always legal, even if OpTy 6212 // is an incomplete type or void. It would be possible to warn about 6213 // dereferencing a void pointer, but it's completely well-defined, and such a 6214 // warning is unlikely to catch any mistakes. 6215 if (const PointerType *PT = OpTy->getAs<PointerType>()) 6216 Result = PT->getPointeeType(); 6217 else if (const ObjCObjectPointerType *OPT = 6218 OpTy->getAs<ObjCObjectPointerType>()) 6219 Result = OPT->getPointeeType(); 6220 6221 if (Result.isNull()) { 6222 Diag(OpLoc, diag::err_typecheck_indirection_requires_pointer) 6223 << OpTy << Op->getSourceRange(); 6224 return QualType(); 6225 } 6226 6227 return Result; 6228} 6229 6230static inline BinaryOperator::Opcode ConvertTokenKindToBinaryOpcode( 6231 tok::TokenKind Kind) { 6232 BinaryOperator::Opcode Opc; 6233 switch (Kind) { 6234 default: assert(0 && "Unknown binop!"); 6235 case tok::periodstar: Opc = BinaryOperator::PtrMemD; break; 6236 case tok::arrowstar: Opc = BinaryOperator::PtrMemI; break; 6237 case tok::star: Opc = BinaryOperator::Mul; break; 6238 case tok::slash: Opc = BinaryOperator::Div; break; 6239 case tok::percent: Opc = BinaryOperator::Rem; break; 6240 case tok::plus: Opc = BinaryOperator::Add; break; 6241 case tok::minus: Opc = BinaryOperator::Sub; break; 6242 case tok::lessless: Opc = BinaryOperator::Shl; break; 6243 case tok::greatergreater: Opc = BinaryOperator::Shr; break; 6244 case tok::lessequal: Opc = BinaryOperator::LE; break; 6245 case tok::less: Opc = BinaryOperator::LT; break; 6246 case tok::greaterequal: Opc = BinaryOperator::GE; break; 6247 case tok::greater: Opc = BinaryOperator::GT; break; 6248 case tok::exclaimequal: Opc = BinaryOperator::NE; break; 6249 case tok::equalequal: Opc = BinaryOperator::EQ; break; 6250 case tok::amp: Opc = BinaryOperator::And; break; 6251 case tok::caret: Opc = BinaryOperator::Xor; break; 6252 case tok::pipe: Opc = BinaryOperator::Or; break; 6253 case tok::ampamp: Opc = BinaryOperator::LAnd; break; 6254 case tok::pipepipe: Opc = BinaryOperator::LOr; break; 6255 case tok::equal: Opc = BinaryOperator::Assign; break; 6256 case tok::starequal: Opc = BinaryOperator::MulAssign; break; 6257 case tok::slashequal: Opc = BinaryOperator::DivAssign; break; 6258 case tok::percentequal: Opc = BinaryOperator::RemAssign; break; 6259 case tok::plusequal: Opc = BinaryOperator::AddAssign; break; 6260 case tok::minusequal: Opc = BinaryOperator::SubAssign; break; 6261 case tok::lesslessequal: Opc = BinaryOperator::ShlAssign; break; 6262 case tok::greatergreaterequal: Opc = BinaryOperator::ShrAssign; break; 6263 case tok::ampequal: Opc = BinaryOperator::AndAssign; break; 6264 case tok::caretequal: Opc = BinaryOperator::XorAssign; break; 6265 case tok::pipeequal: Opc = BinaryOperator::OrAssign; break; 6266 case tok::comma: Opc = BinaryOperator::Comma; break; 6267 } 6268 return Opc; 6269} 6270 6271static inline UnaryOperator::Opcode ConvertTokenKindToUnaryOpcode( 6272 tok::TokenKind Kind) { 6273 UnaryOperator::Opcode Opc; 6274 switch (Kind) { 6275 default: assert(0 && "Unknown unary op!"); 6276 case tok::plusplus: Opc = UnaryOperator::PreInc; break; 6277 case tok::minusminus: Opc = UnaryOperator::PreDec; break; 6278 case tok::amp: Opc = UnaryOperator::AddrOf; break; 6279 case tok::star: Opc = UnaryOperator::Deref; break; 6280 case tok::plus: Opc = UnaryOperator::Plus; break; 6281 case tok::minus: Opc = UnaryOperator::Minus; break; 6282 case tok::tilde: Opc = UnaryOperator::Not; break; 6283 case tok::exclaim: Opc = UnaryOperator::LNot; break; 6284 case tok::kw___real: Opc = UnaryOperator::Real; break; 6285 case tok::kw___imag: Opc = UnaryOperator::Imag; break; 6286 case tok::kw___extension__: Opc = UnaryOperator::Extension; break; 6287 } 6288 return Opc; 6289} 6290 6291/// CreateBuiltinBinOp - Creates a new built-in binary operation with 6292/// operator @p Opc at location @c TokLoc. This routine only supports 6293/// built-in operations; ActOnBinOp handles overloaded operators. 6294Action::OwningExprResult Sema::CreateBuiltinBinOp(SourceLocation OpLoc, 6295 unsigned Op, 6296 Expr *lhs, Expr *rhs) { 6297 QualType ResultTy; // Result type of the binary operator. 6298 BinaryOperator::Opcode Opc = (BinaryOperator::Opcode)Op; 6299 // The following two variables are used for compound assignment operators 6300 QualType CompLHSTy; // Type of LHS after promotions for computation 6301 QualType CompResultTy; // Type of computation result 6302 6303 switch (Opc) { 6304 case BinaryOperator::Assign: 6305 ResultTy = CheckAssignmentOperands(lhs, rhs, OpLoc, QualType()); 6306 break; 6307 case BinaryOperator::PtrMemD: 6308 case BinaryOperator::PtrMemI: 6309 ResultTy = CheckPointerToMemberOperands(lhs, rhs, OpLoc, 6310 Opc == BinaryOperator::PtrMemI); 6311 break; 6312 case BinaryOperator::Mul: 6313 case BinaryOperator::Div: 6314 ResultTy = CheckMultiplyDivideOperands(lhs, rhs, OpLoc, false, 6315 Opc == BinaryOperator::Div); 6316 break; 6317 case BinaryOperator::Rem: 6318 ResultTy = CheckRemainderOperands(lhs, rhs, OpLoc); 6319 break; 6320 case BinaryOperator::Add: 6321 ResultTy = CheckAdditionOperands(lhs, rhs, OpLoc); 6322 break; 6323 case BinaryOperator::Sub: 6324 ResultTy = CheckSubtractionOperands(lhs, rhs, OpLoc); 6325 break; 6326 case BinaryOperator::Shl: 6327 case BinaryOperator::Shr: 6328 ResultTy = CheckShiftOperands(lhs, rhs, OpLoc); 6329 break; 6330 case BinaryOperator::LE: 6331 case BinaryOperator::LT: 6332 case BinaryOperator::GE: 6333 case BinaryOperator::GT: 6334 ResultTy = CheckCompareOperands(lhs, rhs, OpLoc, Opc, true); 6335 break; 6336 case BinaryOperator::EQ: 6337 case BinaryOperator::NE: 6338 ResultTy = CheckCompareOperands(lhs, rhs, OpLoc, Opc, false); 6339 break; 6340 case BinaryOperator::And: 6341 case BinaryOperator::Xor: 6342 case BinaryOperator::Or: 6343 ResultTy = CheckBitwiseOperands(lhs, rhs, OpLoc); 6344 break; 6345 case BinaryOperator::LAnd: 6346 case BinaryOperator::LOr: 6347 ResultTy = CheckLogicalOperands(lhs, rhs, OpLoc); 6348 break; 6349 case BinaryOperator::MulAssign: 6350 case BinaryOperator::DivAssign: 6351 CompResultTy = CheckMultiplyDivideOperands(lhs, rhs, OpLoc, true, 6352 Opc == BinaryOperator::DivAssign); 6353 CompLHSTy = CompResultTy; 6354 if (!CompResultTy.isNull()) 6355 ResultTy = CheckAssignmentOperands(lhs, rhs, OpLoc, CompResultTy); 6356 break; 6357 case BinaryOperator::RemAssign: 6358 CompResultTy = CheckRemainderOperands(lhs, rhs, OpLoc, true); 6359 CompLHSTy = CompResultTy; 6360 if (!CompResultTy.isNull()) 6361 ResultTy = CheckAssignmentOperands(lhs, rhs, OpLoc, CompResultTy); 6362 break; 6363 case BinaryOperator::AddAssign: 6364 CompResultTy = CheckAdditionOperands(lhs, rhs, OpLoc, &CompLHSTy); 6365 if (!CompResultTy.isNull()) 6366 ResultTy = CheckAssignmentOperands(lhs, rhs, OpLoc, CompResultTy); 6367 break; 6368 case BinaryOperator::SubAssign: 6369 CompResultTy = CheckSubtractionOperands(lhs, rhs, OpLoc, &CompLHSTy); 6370 if (!CompResultTy.isNull()) 6371 ResultTy = CheckAssignmentOperands(lhs, rhs, OpLoc, CompResultTy); 6372 break; 6373 case BinaryOperator::ShlAssign: 6374 case BinaryOperator::ShrAssign: 6375 CompResultTy = CheckShiftOperands(lhs, rhs, OpLoc, true); 6376 CompLHSTy = CompResultTy; 6377 if (!CompResultTy.isNull()) 6378 ResultTy = CheckAssignmentOperands(lhs, rhs, OpLoc, CompResultTy); 6379 break; 6380 case BinaryOperator::AndAssign: 6381 case BinaryOperator::XorAssign: 6382 case BinaryOperator::OrAssign: 6383 CompResultTy = CheckBitwiseOperands(lhs, rhs, OpLoc, true); 6384 CompLHSTy = CompResultTy; 6385 if (!CompResultTy.isNull()) 6386 ResultTy = CheckAssignmentOperands(lhs, rhs, OpLoc, CompResultTy); 6387 break; 6388 case BinaryOperator::Comma: 6389 ResultTy = CheckCommaOperands(lhs, rhs, OpLoc); 6390 break; 6391 } 6392 if (ResultTy.isNull()) 6393 return ExprError(); 6394 if (CompResultTy.isNull()) 6395 return Owned(new (Context) BinaryOperator(lhs, rhs, Opc, ResultTy, OpLoc)); 6396 else 6397 return Owned(new (Context) CompoundAssignOperator(lhs, rhs, Opc, ResultTy, 6398 CompLHSTy, CompResultTy, 6399 OpLoc)); 6400} 6401 6402/// SuggestParentheses - Emit a diagnostic together with a fixit hint that wraps 6403/// ParenRange in parentheses. 6404static void SuggestParentheses(Sema &Self, SourceLocation Loc, 6405 const PartialDiagnostic &PD, 6406 const PartialDiagnostic &FirstNote, 6407 SourceRange FirstParenRange, 6408 const PartialDiagnostic &SecondNote, 6409 SourceRange SecondParenRange) { 6410 Self.Diag(Loc, PD); 6411 6412 if (!FirstNote.getDiagID()) 6413 return; 6414 6415 SourceLocation EndLoc = Self.PP.getLocForEndOfToken(FirstParenRange.getEnd()); 6416 if (!FirstParenRange.getEnd().isFileID() || EndLoc.isInvalid()) { 6417 // We can't display the parentheses, so just return. 6418 return; 6419 } 6420 6421 Self.Diag(Loc, FirstNote) 6422 << FixItHint::CreateInsertion(FirstParenRange.getBegin(), "(") 6423 << FixItHint::CreateInsertion(EndLoc, ")"); 6424 6425 if (!SecondNote.getDiagID()) 6426 return; 6427 6428 EndLoc = Self.PP.getLocForEndOfToken(SecondParenRange.getEnd()); 6429 if (!SecondParenRange.getEnd().isFileID() || EndLoc.isInvalid()) { 6430 // We can't display the parentheses, so just dig the 6431 // warning/error and return. 6432 Self.Diag(Loc, SecondNote); 6433 return; 6434 } 6435 6436 Self.Diag(Loc, SecondNote) 6437 << FixItHint::CreateInsertion(SecondParenRange.getBegin(), "(") 6438 << FixItHint::CreateInsertion(EndLoc, ")"); 6439} 6440 6441/// DiagnoseBitwisePrecedence - Emit a warning when bitwise and comparison 6442/// operators are mixed in a way that suggests that the programmer forgot that 6443/// comparison operators have higher precedence. The most typical example of 6444/// such code is "flags & 0x0020 != 0", which is equivalent to "flags & 1". 6445static void DiagnoseBitwisePrecedence(Sema &Self, BinaryOperator::Opcode Opc, 6446 SourceLocation OpLoc,Expr *lhs,Expr *rhs){ 6447 typedef BinaryOperator BinOp; 6448 BinOp::Opcode lhsopc = static_cast<BinOp::Opcode>(-1), 6449 rhsopc = static_cast<BinOp::Opcode>(-1); 6450 if (BinOp *BO = dyn_cast<BinOp>(lhs)) 6451 lhsopc = BO->getOpcode(); 6452 if (BinOp *BO = dyn_cast<BinOp>(rhs)) 6453 rhsopc = BO->getOpcode(); 6454 6455 // Subs are not binary operators. 6456 if (lhsopc == -1 && rhsopc == -1) 6457 return; 6458 6459 // Bitwise operations are sometimes used as eager logical ops. 6460 // Don't diagnose this. 6461 if ((BinOp::isComparisonOp(lhsopc) || BinOp::isBitwiseOp(lhsopc)) && 6462 (BinOp::isComparisonOp(rhsopc) || BinOp::isBitwiseOp(rhsopc))) 6463 return; 6464 6465 if (BinOp::isComparisonOp(lhsopc)) 6466 SuggestParentheses(Self, OpLoc, 6467 Self.PDiag(diag::warn_precedence_bitwise_rel) 6468 << SourceRange(lhs->getLocStart(), OpLoc) 6469 << BinOp::getOpcodeStr(Opc) << BinOp::getOpcodeStr(lhsopc), 6470 Self.PDiag(diag::note_precedence_bitwise_first) 6471 << BinOp::getOpcodeStr(Opc), 6472 SourceRange(cast<BinOp>(lhs)->getRHS()->getLocStart(), rhs->getLocEnd()), 6473 Self.PDiag(diag::note_precedence_bitwise_silence) 6474 << BinOp::getOpcodeStr(lhsopc), 6475 lhs->getSourceRange()); 6476 else if (BinOp::isComparisonOp(rhsopc)) 6477 SuggestParentheses(Self, OpLoc, 6478 Self.PDiag(diag::warn_precedence_bitwise_rel) 6479 << SourceRange(OpLoc, rhs->getLocEnd()) 6480 << BinOp::getOpcodeStr(Opc) << BinOp::getOpcodeStr(rhsopc), 6481 Self.PDiag(diag::note_precedence_bitwise_first) 6482 << BinOp::getOpcodeStr(Opc), 6483 SourceRange(lhs->getLocEnd(), cast<BinOp>(rhs)->getLHS()->getLocStart()), 6484 Self.PDiag(diag::note_precedence_bitwise_silence) 6485 << BinOp::getOpcodeStr(rhsopc), 6486 rhs->getSourceRange()); 6487} 6488 6489/// DiagnoseBinOpPrecedence - Emit warnings for expressions with tricky 6490/// precedence. This currently diagnoses only "arg1 'bitwise' arg2 'eq' arg3". 6491/// But it could also warn about arg1 && arg2 || arg3, as GCC 4.3+ does. 6492static void DiagnoseBinOpPrecedence(Sema &Self, BinaryOperator::Opcode Opc, 6493 SourceLocation OpLoc, Expr *lhs, Expr *rhs){ 6494 if (BinaryOperator::isBitwiseOp(Opc)) 6495 DiagnoseBitwisePrecedence(Self, Opc, OpLoc, lhs, rhs); 6496} 6497 6498// Binary Operators. 'Tok' is the token for the operator. 6499Action::OwningExprResult Sema::ActOnBinOp(Scope *S, SourceLocation TokLoc, 6500 tok::TokenKind Kind, 6501 ExprArg LHS, ExprArg RHS) { 6502 BinaryOperator::Opcode Opc = ConvertTokenKindToBinaryOpcode(Kind); 6503 Expr *lhs = LHS.takeAs<Expr>(), *rhs = RHS.takeAs<Expr>(); 6504 6505 assert((lhs != 0) && "ActOnBinOp(): missing left expression"); 6506 assert((rhs != 0) && "ActOnBinOp(): missing right expression"); 6507 6508 // Emit warnings for tricky precedence issues, e.g. "bitfield & 0x4 == 0" 6509 DiagnoseBinOpPrecedence(*this, Opc, TokLoc, lhs, rhs); 6510 6511 return BuildBinOp(S, TokLoc, Opc, lhs, rhs); 6512} 6513 6514Action::OwningExprResult Sema::BuildBinOp(Scope *S, SourceLocation OpLoc, 6515 BinaryOperator::Opcode Opc, 6516 Expr *lhs, Expr *rhs) { 6517 if (getLangOptions().CPlusPlus && 6518 (lhs->getType()->isOverloadableType() || 6519 rhs->getType()->isOverloadableType())) { 6520 // Find all of the overloaded operators visible from this 6521 // point. We perform both an operator-name lookup from the local 6522 // scope and an argument-dependent lookup based on the types of 6523 // the arguments. 6524 UnresolvedSet<16> Functions; 6525 OverloadedOperatorKind OverOp = BinaryOperator::getOverloadedOperator(Opc); 6526 if (S && OverOp != OO_None) 6527 LookupOverloadedOperatorName(OverOp, S, lhs->getType(), rhs->getType(), 6528 Functions); 6529 6530 // Build the (potentially-overloaded, potentially-dependent) 6531 // binary operation. 6532 return CreateOverloadedBinOp(OpLoc, Opc, Functions, lhs, rhs); 6533 } 6534 6535 // Build a built-in binary operation. 6536 return CreateBuiltinBinOp(OpLoc, Opc, lhs, rhs); 6537} 6538 6539Action::OwningExprResult Sema::CreateBuiltinUnaryOp(SourceLocation OpLoc, 6540 unsigned OpcIn, 6541 ExprArg InputArg) { 6542 UnaryOperator::Opcode Opc = static_cast<UnaryOperator::Opcode>(OpcIn); 6543 6544 // FIXME: Input is modified below, but InputArg is not updated appropriately. 6545 Expr *Input = (Expr *)InputArg.get(); 6546 QualType resultType; 6547 switch (Opc) { 6548 case UnaryOperator::OffsetOf: 6549 assert(false && "Invalid unary operator"); 6550 break; 6551 6552 case UnaryOperator::PreInc: 6553 case UnaryOperator::PreDec: 6554 case UnaryOperator::PostInc: 6555 case UnaryOperator::PostDec: 6556 resultType = CheckIncrementDecrementOperand(Input, OpLoc, 6557 Opc == UnaryOperator::PreInc || 6558 Opc == UnaryOperator::PostInc, 6559 Opc == UnaryOperator::PreInc || 6560 Opc == UnaryOperator::PreDec); 6561 break; 6562 case UnaryOperator::AddrOf: 6563 resultType = CheckAddressOfOperand(Input, OpLoc); 6564 break; 6565 case UnaryOperator::Deref: 6566 DefaultFunctionArrayLvalueConversion(Input); 6567 resultType = CheckIndirectionOperand(Input, OpLoc); 6568 break; 6569 case UnaryOperator::Plus: 6570 case UnaryOperator::Minus: 6571 UsualUnaryConversions(Input); 6572 resultType = Input->getType(); 6573 if (resultType->isDependentType()) 6574 break; 6575 if (resultType->isArithmeticType() || // C99 6.5.3.3p1 6576 resultType->isVectorType()) 6577 break; 6578 else if (getLangOptions().CPlusPlus && // C++ [expr.unary.op]p6-7 6579 resultType->isEnumeralType()) 6580 break; 6581 else if (getLangOptions().CPlusPlus && // C++ [expr.unary.op]p6 6582 Opc == UnaryOperator::Plus && 6583 resultType->isPointerType()) 6584 break; 6585 6586 return ExprError(Diag(OpLoc, diag::err_typecheck_unary_expr) 6587 << resultType << Input->getSourceRange()); 6588 case UnaryOperator::Not: // bitwise complement 6589 UsualUnaryConversions(Input); 6590 resultType = Input->getType(); 6591 if (resultType->isDependentType()) 6592 break; 6593 // C99 6.5.3.3p1. We allow complex int and float as a GCC extension. 6594 if (resultType->isComplexType() || resultType->isComplexIntegerType()) 6595 // C99 does not support '~' for complex conjugation. 6596 Diag(OpLoc, diag::ext_integer_complement_complex) 6597 << resultType << Input->getSourceRange(); 6598 else if (!resultType->isIntegerType()) 6599 return ExprError(Diag(OpLoc, diag::err_typecheck_unary_expr) 6600 << resultType << Input->getSourceRange()); 6601 break; 6602 case UnaryOperator::LNot: // logical negation 6603 // Unlike +/-/~, integer promotions aren't done here (C99 6.5.3.3p5). 6604 DefaultFunctionArrayLvalueConversion(Input); 6605 resultType = Input->getType(); 6606 if (resultType->isDependentType()) 6607 break; 6608 if (!resultType->isScalarType()) // C99 6.5.3.3p1 6609 return ExprError(Diag(OpLoc, diag::err_typecheck_unary_expr) 6610 << resultType << Input->getSourceRange()); 6611 // LNot always has type int. C99 6.5.3.3p5. 6612 // In C++, it's bool. C++ 5.3.1p8 6613 resultType = getLangOptions().CPlusPlus ? Context.BoolTy : Context.IntTy; 6614 break; 6615 case UnaryOperator::Real: 6616 case UnaryOperator::Imag: 6617 resultType = CheckRealImagOperand(Input, OpLoc, Opc == UnaryOperator::Real); 6618 break; 6619 case UnaryOperator::Extension: 6620 resultType = Input->getType(); 6621 break; 6622 } 6623 if (resultType.isNull()) 6624 return ExprError(); 6625 6626 InputArg.release(); 6627 return Owned(new (Context) UnaryOperator(Input, Opc, resultType, OpLoc)); 6628} 6629 6630Action::OwningExprResult Sema::BuildUnaryOp(Scope *S, SourceLocation OpLoc, 6631 UnaryOperator::Opcode Opc, 6632 ExprArg input) { 6633 Expr *Input = (Expr*)input.get(); 6634 if (getLangOptions().CPlusPlus && Input->getType()->isOverloadableType() && 6635 Opc != UnaryOperator::Extension) { 6636 // Find all of the overloaded operators visible from this 6637 // point. We perform both an operator-name lookup from the local 6638 // scope and an argument-dependent lookup based on the types of 6639 // the arguments. 6640 UnresolvedSet<16> Functions; 6641 OverloadedOperatorKind OverOp = UnaryOperator::getOverloadedOperator(Opc); 6642 if (S && OverOp != OO_None) 6643 LookupOverloadedOperatorName(OverOp, S, Input->getType(), QualType(), 6644 Functions); 6645 6646 return CreateOverloadedUnaryOp(OpLoc, Opc, Functions, move(input)); 6647 } 6648 6649 return CreateBuiltinUnaryOp(OpLoc, Opc, move(input)); 6650} 6651 6652// Unary Operators. 'Tok' is the token for the operator. 6653Action::OwningExprResult Sema::ActOnUnaryOp(Scope *S, SourceLocation OpLoc, 6654 tok::TokenKind Op, ExprArg input) { 6655 return BuildUnaryOp(S, OpLoc, ConvertTokenKindToUnaryOpcode(Op), move(input)); 6656} 6657 6658/// ActOnAddrLabel - Parse the GNU address of label extension: "&&foo". 6659Sema::OwningExprResult Sema::ActOnAddrLabel(SourceLocation OpLoc, 6660 SourceLocation LabLoc, 6661 IdentifierInfo *LabelII) { 6662 // Look up the record for this label identifier. 6663 LabelStmt *&LabelDecl = getLabelMap()[LabelII]; 6664 6665 // If we haven't seen this label yet, create a forward reference. It 6666 // will be validated and/or cleaned up in ActOnFinishFunctionBody. 6667 if (LabelDecl == 0) 6668 LabelDecl = new (Context) LabelStmt(LabLoc, LabelII, 0); 6669 6670 // Create the AST node. The address of a label always has type 'void*'. 6671 return Owned(new (Context) AddrLabelExpr(OpLoc, LabLoc, LabelDecl, 6672 Context.getPointerType(Context.VoidTy))); 6673} 6674 6675Sema::OwningExprResult 6676Sema::ActOnStmtExpr(SourceLocation LPLoc, StmtArg substmt, 6677 SourceLocation RPLoc) { // "({..})" 6678 Stmt *SubStmt = static_cast<Stmt*>(substmt.get()); 6679 assert(SubStmt && isa<CompoundStmt>(SubStmt) && "Invalid action invocation!"); 6680 CompoundStmt *Compound = cast<CompoundStmt>(SubStmt); 6681 6682 bool isFileScope 6683 = (getCurFunctionOrMethodDecl() == 0) && (getCurBlock() == 0); 6684 if (isFileScope) 6685 return ExprError(Diag(LPLoc, diag::err_stmtexpr_file_scope)); 6686 6687 // FIXME: there are a variety of strange constraints to enforce here, for 6688 // example, it is not possible to goto into a stmt expression apparently. 6689 // More semantic analysis is needed. 6690 6691 // If there are sub stmts in the compound stmt, take the type of the last one 6692 // as the type of the stmtexpr. 6693 QualType Ty = Context.VoidTy; 6694 6695 if (!Compound->body_empty()) { 6696 Stmt *LastStmt = Compound->body_back(); 6697 // If LastStmt is a label, skip down through into the body. 6698 while (LabelStmt *Label = dyn_cast<LabelStmt>(LastStmt)) 6699 LastStmt = Label->getSubStmt(); 6700 6701 if (Expr *LastExpr = dyn_cast<Expr>(LastStmt)) 6702 Ty = LastExpr->getType(); 6703 } 6704 6705 // FIXME: Check that expression type is complete/non-abstract; statement 6706 // expressions are not lvalues. 6707 6708 substmt.release(); 6709 return Owned(new (Context) StmtExpr(Compound, Ty, LPLoc, RPLoc)); 6710} 6711 6712Sema::OwningExprResult Sema::BuildBuiltinOffsetOf(SourceLocation BuiltinLoc, 6713 TypeSourceInfo *TInfo, 6714 OffsetOfComponent *CompPtr, 6715 unsigned NumComponents, 6716 SourceLocation RParenLoc) { 6717 QualType ArgTy = TInfo->getType(); 6718 bool Dependent = ArgTy->isDependentType(); 6719 SourceRange TypeRange = TInfo->getTypeLoc().getLocalSourceRange(); 6720 6721 // We must have at least one component that refers to the type, and the first 6722 // one is known to be a field designator. Verify that the ArgTy represents 6723 // a struct/union/class. 6724 if (!Dependent && !ArgTy->isRecordType()) 6725 return ExprError(Diag(BuiltinLoc, diag::err_offsetof_record_type) 6726 << ArgTy << TypeRange); 6727 6728 // Type must be complete per C99 7.17p3 because a declaring a variable 6729 // with an incomplete type would be ill-formed. 6730 if (!Dependent 6731 && RequireCompleteType(BuiltinLoc, ArgTy, 6732 PDiag(diag::err_offsetof_incomplete_type) 6733 << TypeRange)) 6734 return ExprError(); 6735 6736 // offsetof with non-identifier designators (e.g. "offsetof(x, a.b[c])") are a 6737 // GCC extension, diagnose them. 6738 // FIXME: This diagnostic isn't actually visible because the location is in 6739 // a system header! 6740 if (NumComponents != 1) 6741 Diag(BuiltinLoc, diag::ext_offsetof_extended_field_designator) 6742 << SourceRange(CompPtr[1].LocStart, CompPtr[NumComponents-1].LocEnd); 6743 6744 bool DidWarnAboutNonPOD = false; 6745 QualType CurrentType = ArgTy; 6746 typedef OffsetOfExpr::OffsetOfNode OffsetOfNode; 6747 llvm::SmallVector<OffsetOfNode, 4> Comps; 6748 llvm::SmallVector<Expr*, 4> Exprs; 6749 for (unsigned i = 0; i != NumComponents; ++i) { 6750 const OffsetOfComponent &OC = CompPtr[i]; 6751 if (OC.isBrackets) { 6752 // Offset of an array sub-field. TODO: Should we allow vector elements? 6753 if (!CurrentType->isDependentType()) { 6754 const ArrayType *AT = Context.getAsArrayType(CurrentType); 6755 if(!AT) 6756 return ExprError(Diag(OC.LocEnd, diag::err_offsetof_array_type) 6757 << CurrentType); 6758 CurrentType = AT->getElementType(); 6759 } else 6760 CurrentType = Context.DependentTy; 6761 6762 // The expression must be an integral expression. 6763 // FIXME: An integral constant expression? 6764 Expr *Idx = static_cast<Expr*>(OC.U.E); 6765 if (!Idx->isTypeDependent() && !Idx->isValueDependent() && 6766 !Idx->getType()->isIntegerType()) 6767 return ExprError(Diag(Idx->getLocStart(), 6768 diag::err_typecheck_subscript_not_integer) 6769 << Idx->getSourceRange()); 6770 6771 // Record this array index. 6772 Comps.push_back(OffsetOfNode(OC.LocStart, Exprs.size(), OC.LocEnd)); 6773 Exprs.push_back(Idx); 6774 continue; 6775 } 6776 6777 // Offset of a field. 6778 if (CurrentType->isDependentType()) { 6779 // We have the offset of a field, but we can't look into the dependent 6780 // type. Just record the identifier of the field. 6781 Comps.push_back(OffsetOfNode(OC.LocStart, OC.U.IdentInfo, OC.LocEnd)); 6782 CurrentType = Context.DependentTy; 6783 continue; 6784 } 6785 6786 // We need to have a complete type to look into. 6787 if (RequireCompleteType(OC.LocStart, CurrentType, 6788 diag::err_offsetof_incomplete_type)) 6789 return ExprError(); 6790 6791 // Look for the designated field. 6792 const RecordType *RC = CurrentType->getAs<RecordType>(); 6793 if (!RC) 6794 return ExprError(Diag(OC.LocEnd, diag::err_offsetof_record_type) 6795 << CurrentType); 6796 RecordDecl *RD = RC->getDecl(); 6797 6798 // C++ [lib.support.types]p5: 6799 // The macro offsetof accepts a restricted set of type arguments in this 6800 // International Standard. type shall be a POD structure or a POD union 6801 // (clause 9). 6802 if (CXXRecordDecl *CRD = dyn_cast<CXXRecordDecl>(RD)) { 6803 if (!CRD->isPOD() && !DidWarnAboutNonPOD && 6804 DiagRuntimeBehavior(BuiltinLoc, 6805 PDiag(diag::warn_offsetof_non_pod_type) 6806 << SourceRange(CompPtr[0].LocStart, OC.LocEnd) 6807 << CurrentType)) 6808 DidWarnAboutNonPOD = true; 6809 } 6810 6811 // Look for the field. 6812 LookupResult R(*this, OC.U.IdentInfo, OC.LocStart, LookupMemberName); 6813 LookupQualifiedName(R, RD); 6814 FieldDecl *MemberDecl = R.getAsSingle<FieldDecl>(); 6815 if (!MemberDecl) 6816 return ExprError(Diag(BuiltinLoc, diag::err_no_member) 6817 << OC.U.IdentInfo << RD << SourceRange(OC.LocStart, 6818 OC.LocEnd)); 6819 6820 // C99 7.17p3: 6821 // (If the specified member is a bit-field, the behavior is undefined.) 6822 // 6823 // We diagnose this as an error. 6824 if (MemberDecl->getBitWidth()) { 6825 Diag(OC.LocEnd, diag::err_offsetof_bitfield) 6826 << MemberDecl->getDeclName() 6827 << SourceRange(BuiltinLoc, RParenLoc); 6828 Diag(MemberDecl->getLocation(), diag::note_bitfield_decl); 6829 return ExprError(); 6830 } 6831 6832 // If the member was found in a base class, introduce OffsetOfNodes for 6833 // the base class indirections. 6834 CXXBasePaths Paths(/*FindAmbiguities=*/true, /*RecordPaths=*/true, 6835 /*DetectVirtual=*/false); 6836 if (IsDerivedFrom(CurrentType, 6837 Context.getTypeDeclType(MemberDecl->getParent()), 6838 Paths)) { 6839 CXXBasePath &Path = Paths.front(); 6840 for (CXXBasePath::iterator B = Path.begin(), BEnd = Path.end(); 6841 B != BEnd; ++B) 6842 Comps.push_back(OffsetOfNode(B->Base)); 6843 } 6844 6845 if (cast<RecordDecl>(MemberDecl->getDeclContext())-> 6846 isAnonymousStructOrUnion()) { 6847 llvm::SmallVector<FieldDecl*, 4> Path; 6848 BuildAnonymousStructUnionMemberPath(MemberDecl, Path); 6849 unsigned n = Path.size(); 6850 for (int j = n - 1; j > -1; --j) 6851 Comps.push_back(OffsetOfNode(OC.LocStart, Path[j], OC.LocEnd)); 6852 } else { 6853 Comps.push_back(OffsetOfNode(OC.LocStart, MemberDecl, OC.LocEnd)); 6854 } 6855 CurrentType = MemberDecl->getType().getNonReferenceType(); 6856 } 6857 6858 return Owned(OffsetOfExpr::Create(Context, Context.getSizeType(), BuiltinLoc, 6859 TInfo, Comps.data(), Comps.size(), 6860 Exprs.data(), Exprs.size(), RParenLoc)); 6861} 6862 6863Sema::OwningExprResult Sema::ActOnBuiltinOffsetOf(Scope *S, 6864 SourceLocation BuiltinLoc, 6865 SourceLocation TypeLoc, 6866 TypeTy *argty, 6867 OffsetOfComponent *CompPtr, 6868 unsigned NumComponents, 6869 SourceLocation RPLoc) { 6870 6871 TypeSourceInfo *ArgTInfo; 6872 QualType ArgTy = GetTypeFromParser(argty, &ArgTInfo); 6873 if (ArgTy.isNull()) 6874 return ExprError(); 6875 6876 if (getLangOptions().CPlusPlus) { 6877 if (!ArgTInfo) 6878 ArgTInfo = Context.getTrivialTypeSourceInfo(ArgTy, TypeLoc); 6879 6880 return BuildBuiltinOffsetOf(BuiltinLoc, ArgTInfo, CompPtr, NumComponents, 6881 RPLoc); 6882 } 6883 6884 // FIXME: The code below is marked for death, once we have proper CodeGen 6885 // support for non-constant OffsetOf expressions. 6886 6887 bool Dependent = ArgTy->isDependentType(); 6888 6889 // We must have at least one component that refers to the type, and the first 6890 // one is known to be a field designator. Verify that the ArgTy represents 6891 // a struct/union/class. 6892 if (!Dependent && !ArgTy->isRecordType()) 6893 return ExprError(Diag(TypeLoc, diag::err_offsetof_record_type) << ArgTy); 6894 6895 // FIXME: Type must be complete per C99 7.17p3 because a declaring a variable 6896 // with an incomplete type would be illegal. 6897 6898 // Otherwise, create a null pointer as the base, and iteratively process 6899 // the offsetof designators. 6900 QualType ArgTyPtr = Context.getPointerType(ArgTy); 6901 Expr* Res = new (Context) ImplicitValueInitExpr(ArgTyPtr); 6902 Res = new (Context) UnaryOperator(Res, UnaryOperator::Deref, 6903 ArgTy, SourceLocation()); 6904 6905 // offsetof with non-identifier designators (e.g. "offsetof(x, a.b[c])") are a 6906 // GCC extension, diagnose them. 6907 // FIXME: This diagnostic isn't actually visible because the location is in 6908 // a system header! 6909 if (NumComponents != 1) 6910 Diag(BuiltinLoc, diag::ext_offsetof_extended_field_designator) 6911 << SourceRange(CompPtr[1].LocStart, CompPtr[NumComponents-1].LocEnd); 6912 6913 if (!Dependent) { 6914 bool DidWarnAboutNonPOD = false; 6915 6916 if (RequireCompleteType(TypeLoc, Res->getType(), 6917 diag::err_offsetof_incomplete_type)) 6918 return ExprError(); 6919 6920 // FIXME: Dependent case loses a lot of information here. And probably 6921 // leaks like a sieve. 6922 for (unsigned i = 0; i != NumComponents; ++i) { 6923 const OffsetOfComponent &OC = CompPtr[i]; 6924 if (OC.isBrackets) { 6925 // Offset of an array sub-field. TODO: Should we allow vector elements? 6926 const ArrayType *AT = Context.getAsArrayType(Res->getType()); 6927 if (!AT) { 6928 Res->Destroy(Context); 6929 return ExprError(Diag(OC.LocEnd, diag::err_offsetof_array_type) 6930 << Res->getType()); 6931 } 6932 6933 // FIXME: C++: Verify that operator[] isn't overloaded. 6934 6935 // Promote the array so it looks more like a normal array subscript 6936 // expression. 6937 DefaultFunctionArrayLvalueConversion(Res); 6938 6939 // C99 6.5.2.1p1 6940 Expr *Idx = static_cast<Expr*>(OC.U.E); 6941 // FIXME: Leaks Res 6942 if (!Idx->isTypeDependent() && !Idx->getType()->isIntegerType()) 6943 return ExprError(Diag(Idx->getLocStart(), 6944 diag::err_typecheck_subscript_not_integer) 6945 << Idx->getSourceRange()); 6946 6947 Res = new (Context) ArraySubscriptExpr(Res, Idx, AT->getElementType(), 6948 OC.LocEnd); 6949 continue; 6950 } 6951 6952 const RecordType *RC = Res->getType()->getAs<RecordType>(); 6953 if (!RC) { 6954 Res->Destroy(Context); 6955 return ExprError(Diag(OC.LocEnd, diag::err_offsetof_record_type) 6956 << Res->getType()); 6957 } 6958 6959 // Get the decl corresponding to this. 6960 RecordDecl *RD = RC->getDecl(); 6961 if (CXXRecordDecl *CRD = dyn_cast<CXXRecordDecl>(RD)) { 6962 if (!CRD->isPOD() && !DidWarnAboutNonPOD && 6963 DiagRuntimeBehavior(BuiltinLoc, 6964 PDiag(diag::warn_offsetof_non_pod_type) 6965 << SourceRange(CompPtr[0].LocStart, OC.LocEnd) 6966 << Res->getType())) 6967 DidWarnAboutNonPOD = true; 6968 } 6969 6970 LookupResult R(*this, OC.U.IdentInfo, OC.LocStart, LookupMemberName); 6971 LookupQualifiedName(R, RD); 6972 6973 FieldDecl *MemberDecl = R.getAsSingle<FieldDecl>(); 6974 // FIXME: Leaks Res 6975 if (!MemberDecl) 6976 return ExprError(Diag(BuiltinLoc, diag::err_no_member) 6977 << OC.U.IdentInfo << RD << SourceRange(OC.LocStart, OC.LocEnd)); 6978 6979 // C99 7.17p3: 6980 // (If the specified member is a bit-field, the behavior is undefined.) 6981 // 6982 // We diagnose this as an error. 6983 if (MemberDecl->getBitWidth()) { 6984 Diag(OC.LocEnd, diag::err_offsetof_bitfield) 6985 << MemberDecl->getDeclName() 6986 << SourceRange(BuiltinLoc, RPLoc); 6987 Diag(MemberDecl->getLocation(), diag::note_bitfield_decl); 6988 return ExprError(); 6989 } 6990 6991 // FIXME: C++: Verify that MemberDecl isn't a static field. 6992 // FIXME: Verify that MemberDecl isn't a bitfield. 6993 if (cast<RecordDecl>(MemberDecl->getDeclContext())->isAnonymousStructOrUnion()) { 6994 Res = BuildAnonymousStructUnionMemberReference( 6995 OC.LocEnd, MemberDecl, Res, OC.LocEnd).takeAs<Expr>(); 6996 } else { 6997 PerformObjectMemberConversion(Res, /*Qualifier=*/0, 6998 *R.begin(), MemberDecl); 6999 // MemberDecl->getType() doesn't get the right qualifiers, but it 7000 // doesn't matter here. 7001 Res = new (Context) MemberExpr(Res, false, MemberDecl, OC.LocEnd, 7002 MemberDecl->getType().getNonReferenceType()); 7003 } 7004 } 7005 } 7006 7007 return Owned(new (Context) UnaryOperator(Res, UnaryOperator::OffsetOf, 7008 Context.getSizeType(), BuiltinLoc)); 7009} 7010 7011 7012Sema::OwningExprResult Sema::ActOnTypesCompatibleExpr(SourceLocation BuiltinLoc, 7013 TypeTy *arg1,TypeTy *arg2, 7014 SourceLocation RPLoc) { 7015 // FIXME: Preserve type source info. 7016 QualType argT1 = GetTypeFromParser(arg1); 7017 QualType argT2 = GetTypeFromParser(arg2); 7018 7019 assert((!argT1.isNull() && !argT2.isNull()) && "Missing type argument(s)"); 7020 7021 if (getLangOptions().CPlusPlus) { 7022 Diag(BuiltinLoc, diag::err_types_compatible_p_in_cplusplus) 7023 << SourceRange(BuiltinLoc, RPLoc); 7024 return ExprError(); 7025 } 7026 7027 return Owned(new (Context) TypesCompatibleExpr(Context.IntTy, BuiltinLoc, 7028 argT1, argT2, RPLoc)); 7029} 7030 7031Sema::OwningExprResult Sema::ActOnChooseExpr(SourceLocation BuiltinLoc, 7032 ExprArg cond, 7033 ExprArg expr1, ExprArg expr2, 7034 SourceLocation RPLoc) { 7035 Expr *CondExpr = static_cast<Expr*>(cond.get()); 7036 Expr *LHSExpr = static_cast<Expr*>(expr1.get()); 7037 Expr *RHSExpr = static_cast<Expr*>(expr2.get()); 7038 7039 assert((CondExpr && LHSExpr && RHSExpr) && "Missing type argument(s)"); 7040 7041 QualType resType; 7042 bool ValueDependent = false; 7043 if (CondExpr->isTypeDependent() || CondExpr->isValueDependent()) { 7044 resType = Context.DependentTy; 7045 ValueDependent = true; 7046 } else { 7047 // The conditional expression is required to be a constant expression. 7048 llvm::APSInt condEval(32); 7049 SourceLocation ExpLoc; 7050 if (!CondExpr->isIntegerConstantExpr(condEval, Context, &ExpLoc)) 7051 return ExprError(Diag(ExpLoc, 7052 diag::err_typecheck_choose_expr_requires_constant) 7053 << CondExpr->getSourceRange()); 7054 7055 // If the condition is > zero, then the AST type is the same as the LSHExpr. 7056 resType = condEval.getZExtValue() ? LHSExpr->getType() : RHSExpr->getType(); 7057 ValueDependent = condEval.getZExtValue() ? LHSExpr->isValueDependent() 7058 : RHSExpr->isValueDependent(); 7059 } 7060 7061 cond.release(); expr1.release(); expr2.release(); 7062 return Owned(new (Context) ChooseExpr(BuiltinLoc, CondExpr, LHSExpr, RHSExpr, 7063 resType, RPLoc, 7064 resType->isDependentType(), 7065 ValueDependent)); 7066} 7067 7068//===----------------------------------------------------------------------===// 7069// Clang Extensions. 7070//===----------------------------------------------------------------------===// 7071 7072/// ActOnBlockStart - This callback is invoked when a block literal is started. 7073void Sema::ActOnBlockStart(SourceLocation CaretLoc, Scope *BlockScope) { 7074 BlockDecl *Block = BlockDecl::Create(Context, CurContext, CaretLoc); 7075 PushBlockScope(BlockScope, Block); 7076 CurContext->addDecl(Block); 7077 if (BlockScope) 7078 PushDeclContext(BlockScope, Block); 7079 else 7080 CurContext = Block; 7081} 7082 7083void Sema::ActOnBlockArguments(Declarator &ParamInfo, Scope *CurScope) { 7084 assert(ParamInfo.getIdentifier()==0 && "block-id should have no identifier!"); 7085 BlockScopeInfo *CurBlock = getCurBlock(); 7086 7087 TypeSourceInfo *Sig = GetTypeForDeclarator(ParamInfo, CurScope); 7088 CurBlock->TheDecl->setSignatureAsWritten(Sig); 7089 QualType T = Sig->getType(); 7090 7091 bool isVariadic; 7092 QualType RetTy; 7093 if (const FunctionType *Fn = T->getAs<FunctionType>()) { 7094 CurBlock->FunctionType = T; 7095 RetTy = Fn->getResultType(); 7096 isVariadic = 7097 !isa<FunctionProtoType>(Fn) || cast<FunctionProtoType>(Fn)->isVariadic(); 7098 } else { 7099 RetTy = T; 7100 isVariadic = false; 7101 } 7102 7103 CurBlock->TheDecl->setIsVariadic(isVariadic); 7104 7105 // Don't allow returning an array by value. 7106 if (RetTy->isArrayType()) { 7107 Diag(ParamInfo.getSourceRange().getBegin(), diag::err_block_returns_array); 7108 return; 7109 } 7110 7111 // Don't allow returning a objc interface by value. 7112 if (RetTy->isObjCObjectType()) { 7113 Diag(ParamInfo.getSourceRange().getBegin(), 7114 diag::err_object_cannot_be_passed_returned_by_value) << 0 << RetTy; 7115 return; 7116 } 7117 7118 // Context.DependentTy is used as a placeholder for a missing block 7119 // return type. TODO: what should we do with declarators like: 7120 // ^ * { ... } 7121 // If the answer is "apply template argument deduction".... 7122 if (RetTy != Context.DependentTy) 7123 CurBlock->ReturnType = RetTy; 7124 7125 // Push block parameters from the declarator if we had them. 7126 llvm::SmallVector<ParmVarDecl*, 8> Params; 7127 if (isa<FunctionProtoType>(T)) { 7128 FunctionProtoTypeLoc TL = cast<FunctionProtoTypeLoc>(Sig->getTypeLoc()); 7129 for (unsigned I = 0, E = TL.getNumArgs(); I != E; ++I) { 7130 ParmVarDecl *Param = TL.getArg(I); 7131 if (Param->getIdentifier() == 0 && 7132 !Param->isImplicit() && 7133 !Param->isInvalidDecl() && 7134 !getLangOptions().CPlusPlus) 7135 Diag(Param->getLocation(), diag::err_parameter_name_omitted); 7136 Params.push_back(Param); 7137 } 7138 7139 // Fake up parameter variables if we have a typedef, like 7140 // ^ fntype { ... } 7141 } else if (const FunctionProtoType *Fn = T->getAs<FunctionProtoType>()) { 7142 for (FunctionProtoType::arg_type_iterator 7143 I = Fn->arg_type_begin(), E = Fn->arg_type_end(); I != E; ++I) { 7144 ParmVarDecl *Param = 7145 BuildParmVarDeclForTypedef(CurBlock->TheDecl, 7146 ParamInfo.getSourceRange().getBegin(), 7147 *I); 7148 Params.push_back(Param); 7149 } 7150 } 7151 7152 // Set the parameters on the block decl. 7153 if (!Params.empty()) 7154 CurBlock->TheDecl->setParams(Params.data(), Params.size()); 7155 7156 // Finally we can process decl attributes. 7157 ProcessDeclAttributes(CurScope, CurBlock->TheDecl, ParamInfo); 7158 7159 if (!isVariadic && CurBlock->TheDecl->getAttr<SentinelAttr>()) { 7160 Diag(ParamInfo.getAttributes()->getLoc(), 7161 diag::warn_attribute_sentinel_not_variadic) << 1; 7162 // FIXME: remove the attribute. 7163 } 7164 7165 // Put the parameter variables in scope. We can bail out immediately 7166 // if we don't have any. 7167 if (Params.empty()) 7168 return; 7169 7170 bool ShouldCheckShadow = 7171 Diags.getDiagnosticLevel(diag::warn_decl_shadow) != Diagnostic::Ignored; 7172 7173 for (BlockDecl::param_iterator AI = CurBlock->TheDecl->param_begin(), 7174 E = CurBlock->TheDecl->param_end(); AI != E; ++AI) { 7175 (*AI)->setOwningFunction(CurBlock->TheDecl); 7176 7177 // If this has an identifier, add it to the scope stack. 7178 if ((*AI)->getIdentifier()) { 7179 if (ShouldCheckShadow) 7180 CheckShadow(CurBlock->TheScope, *AI); 7181 7182 PushOnScopeChains(*AI, CurBlock->TheScope); 7183 } 7184 } 7185} 7186 7187/// ActOnBlockError - If there is an error parsing a block, this callback 7188/// is invoked to pop the information about the block from the action impl. 7189void Sema::ActOnBlockError(SourceLocation CaretLoc, Scope *CurScope) { 7190 // Pop off CurBlock, handle nested blocks. 7191 PopDeclContext(); 7192 PopFunctionOrBlockScope(); 7193 // FIXME: Delete the ParmVarDecl objects as well??? 7194} 7195 7196/// ActOnBlockStmtExpr - This is called when the body of a block statement 7197/// literal was successfully completed. ^(int x){...} 7198Sema::OwningExprResult Sema::ActOnBlockStmtExpr(SourceLocation CaretLoc, 7199 StmtArg body, Scope *CurScope) { 7200 // If blocks are disabled, emit an error. 7201 if (!LangOpts.Blocks) 7202 Diag(CaretLoc, diag::err_blocks_disable); 7203 7204 BlockScopeInfo *BSI = cast<BlockScopeInfo>(FunctionScopes.back()); 7205 7206 PopDeclContext(); 7207 7208 QualType RetTy = Context.VoidTy; 7209 if (!BSI->ReturnType.isNull()) 7210 RetTy = BSI->ReturnType; 7211 7212 bool NoReturn = BSI->TheDecl->getAttr<NoReturnAttr>(); 7213 QualType BlockTy; 7214 7215 // If the user wrote a function type in some form, try to use that. 7216 if (!BSI->FunctionType.isNull()) { 7217 const FunctionType *FTy = BSI->FunctionType->getAs<FunctionType>(); 7218 7219 FunctionType::ExtInfo Ext = FTy->getExtInfo(); 7220 if (NoReturn && !Ext.getNoReturn()) Ext = Ext.withNoReturn(true); 7221 7222 // Turn protoless block types into nullary block types. 7223 if (isa<FunctionNoProtoType>(FTy)) { 7224 BlockTy = Context.getFunctionType(RetTy, 0, 0, false, 0, 7225 false, false, 0, 0, Ext); 7226 7227 // Otherwise, if we don't need to change anything about the function type, 7228 // preserve its sugar structure. 7229 } else if (FTy->getResultType() == RetTy && 7230 (!NoReturn || FTy->getNoReturnAttr())) { 7231 BlockTy = BSI->FunctionType; 7232 7233 // Otherwise, make the minimal modifications to the function type. 7234 } else { 7235 const FunctionProtoType *FPT = cast<FunctionProtoType>(FTy); 7236 BlockTy = Context.getFunctionType(RetTy, 7237 FPT->arg_type_begin(), 7238 FPT->getNumArgs(), 7239 FPT->isVariadic(), 7240 /*quals*/ 0, 7241 FPT->hasExceptionSpec(), 7242 FPT->hasAnyExceptionSpec(), 7243 FPT->getNumExceptions(), 7244 FPT->exception_begin(), 7245 Ext); 7246 } 7247 7248 // If we don't have a function type, just build one from nothing. 7249 } else { 7250 BlockTy = Context.getFunctionType(RetTy, 0, 0, false, 0, 7251 false, false, 0, 0, 7252 FunctionType::ExtInfo(NoReturn, 0, CC_Default)); 7253 } 7254 7255 // FIXME: Check that return/parameter types are complete/non-abstract 7256 DiagnoseUnusedParameters(BSI->TheDecl->param_begin(), 7257 BSI->TheDecl->param_end()); 7258 BlockTy = Context.getBlockPointerType(BlockTy); 7259 7260 // If needed, diagnose invalid gotos and switches in the block. 7261 if (FunctionNeedsScopeChecking() && !hasAnyErrorsInThisFunction()) 7262 DiagnoseInvalidJumps(static_cast<CompoundStmt*>(body.get())); 7263 7264 BSI->TheDecl->setBody(body.takeAs<CompoundStmt>()); 7265 7266 bool Good = true; 7267 // Check goto/label use. 7268 for (llvm::DenseMap<IdentifierInfo*, LabelStmt*>::iterator 7269 I = BSI->LabelMap.begin(), E = BSI->LabelMap.end(); I != E; ++I) { 7270 LabelStmt *L = I->second; 7271 7272 // Verify that we have no forward references left. If so, there was a goto 7273 // or address of a label taken, but no definition of it. 7274 if (L->getSubStmt() != 0) 7275 continue; 7276 7277 // Emit error. 7278 Diag(L->getIdentLoc(), diag::err_undeclared_label_use) << L->getName(); 7279 Good = false; 7280 } 7281 if (!Good) { 7282 PopFunctionOrBlockScope(); 7283 return ExprError(); 7284 } 7285 7286 // Issue any analysis-based warnings. 7287 const sema::AnalysisBasedWarnings::Policy &WP = 7288 AnalysisWarnings.getDefaultPolicy(); 7289 AnalysisWarnings.IssueWarnings(WP, BSI->TheDecl, BlockTy); 7290 7291 Expr *Result = new (Context) BlockExpr(BSI->TheDecl, BlockTy, 7292 BSI->hasBlockDeclRefExprs); 7293 PopFunctionOrBlockScope(); 7294 return Owned(Result); 7295} 7296 7297Sema::OwningExprResult Sema::ActOnVAArg(SourceLocation BuiltinLoc, 7298 ExprArg expr, TypeTy *type, 7299 SourceLocation RPLoc) { 7300 QualType T = GetTypeFromParser(type); 7301 Expr *E = static_cast<Expr*>(expr.get()); 7302 Expr *OrigExpr = E; 7303 7304 InitBuiltinVaListType(); 7305 7306 // Get the va_list type 7307 QualType VaListType = Context.getBuiltinVaListType(); 7308 if (VaListType->isArrayType()) { 7309 // Deal with implicit array decay; for example, on x86-64, 7310 // va_list is an array, but it's supposed to decay to 7311 // a pointer for va_arg. 7312 VaListType = Context.getArrayDecayedType(VaListType); 7313 // Make sure the input expression also decays appropriately. 7314 UsualUnaryConversions(E); 7315 } else { 7316 // Otherwise, the va_list argument must be an l-value because 7317 // it is modified by va_arg. 7318 if (!E->isTypeDependent() && 7319 CheckForModifiableLvalue(E, BuiltinLoc, *this)) 7320 return ExprError(); 7321 } 7322 7323 if (!E->isTypeDependent() && 7324 !Context.hasSameType(VaListType, E->getType())) { 7325 return ExprError(Diag(E->getLocStart(), 7326 diag::err_first_argument_to_va_arg_not_of_type_va_list) 7327 << OrigExpr->getType() << E->getSourceRange()); 7328 } 7329 7330 // FIXME: Check that type is complete/non-abstract 7331 // FIXME: Warn if a non-POD type is passed in. 7332 7333 expr.release(); 7334 return Owned(new (Context) VAArgExpr(BuiltinLoc, E, T.getNonReferenceType(), 7335 RPLoc)); 7336} 7337 7338Sema::OwningExprResult Sema::ActOnGNUNullExpr(SourceLocation TokenLoc) { 7339 // The type of __null will be int or long, depending on the size of 7340 // pointers on the target. 7341 QualType Ty; 7342 if (Context.Target.getPointerWidth(0) == Context.Target.getIntWidth()) 7343 Ty = Context.IntTy; 7344 else 7345 Ty = Context.LongTy; 7346 7347 return Owned(new (Context) GNUNullExpr(Ty, TokenLoc)); 7348} 7349 7350static void MakeObjCStringLiteralFixItHint(Sema& SemaRef, QualType DstType, 7351 Expr *SrcExpr, FixItHint &Hint) { 7352 if (!SemaRef.getLangOptions().ObjC1) 7353 return; 7354 7355 const ObjCObjectPointerType *PT = DstType->getAs<ObjCObjectPointerType>(); 7356 if (!PT) 7357 return; 7358 7359 // Check if the destination is of type 'id'. 7360 if (!PT->isObjCIdType()) { 7361 // Check if the destination is the 'NSString' interface. 7362 const ObjCInterfaceDecl *ID = PT->getInterfaceDecl(); 7363 if (!ID || !ID->getIdentifier()->isStr("NSString")) 7364 return; 7365 } 7366 7367 // Strip off any parens and casts. 7368 StringLiteral *SL = dyn_cast<StringLiteral>(SrcExpr->IgnoreParenCasts()); 7369 if (!SL || SL->isWide()) 7370 return; 7371 7372 Hint = FixItHint::CreateInsertion(SL->getLocStart(), "@"); 7373} 7374 7375bool Sema::DiagnoseAssignmentResult(AssignConvertType ConvTy, 7376 SourceLocation Loc, 7377 QualType DstType, QualType SrcType, 7378 Expr *SrcExpr, AssignmentAction Action, 7379 bool *Complained) { 7380 if (Complained) 7381 *Complained = false; 7382 7383 // Decode the result (notice that AST's are still created for extensions). 7384 bool isInvalid = false; 7385 unsigned DiagKind; 7386 FixItHint Hint; 7387 7388 switch (ConvTy) { 7389 default: assert(0 && "Unknown conversion type"); 7390 case Compatible: return false; 7391 case PointerToInt: 7392 DiagKind = diag::ext_typecheck_convert_pointer_int; 7393 break; 7394 case IntToPointer: 7395 DiagKind = diag::ext_typecheck_convert_int_pointer; 7396 break; 7397 case IncompatiblePointer: 7398 MakeObjCStringLiteralFixItHint(*this, DstType, SrcExpr, Hint); 7399 DiagKind = diag::ext_typecheck_convert_incompatible_pointer; 7400 break; 7401 case IncompatiblePointerSign: 7402 DiagKind = diag::ext_typecheck_convert_incompatible_pointer_sign; 7403 break; 7404 case FunctionVoidPointer: 7405 DiagKind = diag::ext_typecheck_convert_pointer_void_func; 7406 break; 7407 case CompatiblePointerDiscardsQualifiers: 7408 // If the qualifiers lost were because we were applying the 7409 // (deprecated) C++ conversion from a string literal to a char* 7410 // (or wchar_t*), then there was no error (C++ 4.2p2). FIXME: 7411 // Ideally, this check would be performed in 7412 // CheckPointerTypesForAssignment. However, that would require a 7413 // bit of refactoring (so that the second argument is an 7414 // expression, rather than a type), which should be done as part 7415 // of a larger effort to fix CheckPointerTypesForAssignment for 7416 // C++ semantics. 7417 if (getLangOptions().CPlusPlus && 7418 IsStringLiteralToNonConstPointerConversion(SrcExpr, DstType)) 7419 return false; 7420 DiagKind = diag::ext_typecheck_convert_discards_qualifiers; 7421 break; 7422 case IncompatibleNestedPointerQualifiers: 7423 DiagKind = diag::ext_nested_pointer_qualifier_mismatch; 7424 break; 7425 case IntToBlockPointer: 7426 DiagKind = diag::err_int_to_block_pointer; 7427 break; 7428 case IncompatibleBlockPointer: 7429 DiagKind = diag::err_typecheck_convert_incompatible_block_pointer; 7430 break; 7431 case IncompatibleObjCQualifiedId: 7432 // FIXME: Diagnose the problem in ObjCQualifiedIdTypesAreCompatible, since 7433 // it can give a more specific diagnostic. 7434 DiagKind = diag::warn_incompatible_qualified_id; 7435 break; 7436 case IncompatibleVectors: 7437 DiagKind = diag::warn_incompatible_vectors; 7438 break; 7439 case Incompatible: 7440 DiagKind = diag::err_typecheck_convert_incompatible; 7441 isInvalid = true; 7442 break; 7443 } 7444 7445 QualType FirstType, SecondType; 7446 switch (Action) { 7447 case AA_Assigning: 7448 case AA_Initializing: 7449 // The destination type comes first. 7450 FirstType = DstType; 7451 SecondType = SrcType; 7452 break; 7453 7454 case AA_Returning: 7455 case AA_Passing: 7456 case AA_Converting: 7457 case AA_Sending: 7458 case AA_Casting: 7459 // The source type comes first. 7460 FirstType = SrcType; 7461 SecondType = DstType; 7462 break; 7463 } 7464 7465 Diag(Loc, DiagKind) << FirstType << SecondType << Action 7466 << SrcExpr->getSourceRange() << Hint; 7467 if (Complained) 7468 *Complained = true; 7469 return isInvalid; 7470} 7471 7472bool Sema::VerifyIntegerConstantExpression(const Expr *E, llvm::APSInt *Result){ 7473 llvm::APSInt ICEResult; 7474 if (E->isIntegerConstantExpr(ICEResult, Context)) { 7475 if (Result) 7476 *Result = ICEResult; 7477 return false; 7478 } 7479 7480 Expr::EvalResult EvalResult; 7481 7482 if (!E->Evaluate(EvalResult, Context) || !EvalResult.Val.isInt() || 7483 EvalResult.HasSideEffects) { 7484 Diag(E->getExprLoc(), diag::err_expr_not_ice) << E->getSourceRange(); 7485 7486 if (EvalResult.Diag) { 7487 // We only show the note if it's not the usual "invalid subexpression" 7488 // or if it's actually in a subexpression. 7489 if (EvalResult.Diag != diag::note_invalid_subexpr_in_ice || 7490 E->IgnoreParens() != EvalResult.DiagExpr->IgnoreParens()) 7491 Diag(EvalResult.DiagLoc, EvalResult.Diag); 7492 } 7493 7494 return true; 7495 } 7496 7497 Diag(E->getExprLoc(), diag::ext_expr_not_ice) << 7498 E->getSourceRange(); 7499 7500 if (EvalResult.Diag && 7501 Diags.getDiagnosticLevel(diag::ext_expr_not_ice) != Diagnostic::Ignored) 7502 Diag(EvalResult.DiagLoc, EvalResult.Diag); 7503 7504 if (Result) 7505 *Result = EvalResult.Val.getInt(); 7506 return false; 7507} 7508 7509void 7510Sema::PushExpressionEvaluationContext(ExpressionEvaluationContext NewContext) { 7511 ExprEvalContexts.push_back( 7512 ExpressionEvaluationContextRecord(NewContext, ExprTemporaries.size())); 7513} 7514 7515void 7516Sema::PopExpressionEvaluationContext() { 7517 // Pop the current expression evaluation context off the stack. 7518 ExpressionEvaluationContextRecord Rec = ExprEvalContexts.back(); 7519 ExprEvalContexts.pop_back(); 7520 7521 if (Rec.Context == PotentiallyPotentiallyEvaluated) { 7522 if (Rec.PotentiallyReferenced) { 7523 // Mark any remaining declarations in the current position of the stack 7524 // as "referenced". If they were not meant to be referenced, semantic 7525 // analysis would have eliminated them (e.g., in ActOnCXXTypeId). 7526 for (PotentiallyReferencedDecls::iterator 7527 I = Rec.PotentiallyReferenced->begin(), 7528 IEnd = Rec.PotentiallyReferenced->end(); 7529 I != IEnd; ++I) 7530 MarkDeclarationReferenced(I->first, I->second); 7531 } 7532 7533 if (Rec.PotentiallyDiagnosed) { 7534 // Emit any pending diagnostics. 7535 for (PotentiallyEmittedDiagnostics::iterator 7536 I = Rec.PotentiallyDiagnosed->begin(), 7537 IEnd = Rec.PotentiallyDiagnosed->end(); 7538 I != IEnd; ++I) 7539 Diag(I->first, I->second); 7540 } 7541 } 7542 7543 // When are coming out of an unevaluated context, clear out any 7544 // temporaries that we may have created as part of the evaluation of 7545 // the expression in that context: they aren't relevant because they 7546 // will never be constructed. 7547 if (Rec.Context == Unevaluated && 7548 ExprTemporaries.size() > Rec.NumTemporaries) 7549 ExprTemporaries.erase(ExprTemporaries.begin() + Rec.NumTemporaries, 7550 ExprTemporaries.end()); 7551 7552 // Destroy the popped expression evaluation record. 7553 Rec.Destroy(); 7554} 7555 7556/// \brief Note that the given declaration was referenced in the source code. 7557/// 7558/// This routine should be invoke whenever a given declaration is referenced 7559/// in the source code, and where that reference occurred. If this declaration 7560/// reference means that the the declaration is used (C++ [basic.def.odr]p2, 7561/// C99 6.9p3), then the declaration will be marked as used. 7562/// 7563/// \param Loc the location where the declaration was referenced. 7564/// 7565/// \param D the declaration that has been referenced by the source code. 7566void Sema::MarkDeclarationReferenced(SourceLocation Loc, Decl *D) { 7567 assert(D && "No declaration?"); 7568 7569 if (D->isUsed(false)) 7570 return; 7571 7572 // Mark a parameter or variable declaration "used", regardless of whether we're in a 7573 // template or not. The reason for this is that unevaluated expressions 7574 // (e.g. (void)sizeof()) constitute a use for warning purposes (-Wunused-variables and 7575 // -Wunused-parameters) 7576 if (isa<ParmVarDecl>(D) || 7577 (isa<VarDecl>(D) && D->getDeclContext()->isFunctionOrMethod())) { 7578 D->setUsed(true); 7579 return; 7580 } 7581 7582 if (!isa<VarDecl>(D) && !isa<FunctionDecl>(D)) 7583 return; 7584 7585 // Do not mark anything as "used" within a dependent context; wait for 7586 // an instantiation. 7587 if (CurContext->isDependentContext()) 7588 return; 7589 7590 switch (ExprEvalContexts.back().Context) { 7591 case Unevaluated: 7592 // We are in an expression that is not potentially evaluated; do nothing. 7593 return; 7594 7595 case PotentiallyEvaluated: 7596 // We are in a potentially-evaluated expression, so this declaration is 7597 // "used"; handle this below. 7598 break; 7599 7600 case PotentiallyPotentiallyEvaluated: 7601 // We are in an expression that may be potentially evaluated; queue this 7602 // declaration reference until we know whether the expression is 7603 // potentially evaluated. 7604 ExprEvalContexts.back().addReferencedDecl(Loc, D); 7605 return; 7606 } 7607 7608 // Note that this declaration has been used. 7609 if (CXXConstructorDecl *Constructor = dyn_cast<CXXConstructorDecl>(D)) { 7610 unsigned TypeQuals; 7611 if (Constructor->isImplicit() && Constructor->isDefaultConstructor()) { 7612 if (!Constructor->isUsed(false)) 7613 DefineImplicitDefaultConstructor(Loc, Constructor); 7614 } else if (Constructor->isImplicit() && 7615 Constructor->isCopyConstructor(TypeQuals)) { 7616 if (!Constructor->isUsed(false)) 7617 DefineImplicitCopyConstructor(Loc, Constructor, TypeQuals); 7618 } 7619 7620 MarkVTableUsed(Loc, Constructor->getParent()); 7621 } else if (CXXDestructorDecl *Destructor = dyn_cast<CXXDestructorDecl>(D)) { 7622 if (Destructor->isImplicit() && !Destructor->isUsed(false)) 7623 DefineImplicitDestructor(Loc, Destructor); 7624 if (Destructor->isVirtual()) 7625 MarkVTableUsed(Loc, Destructor->getParent()); 7626 } else if (CXXMethodDecl *MethodDecl = dyn_cast<CXXMethodDecl>(D)) { 7627 if (MethodDecl->isImplicit() && MethodDecl->isOverloadedOperator() && 7628 MethodDecl->getOverloadedOperator() == OO_Equal) { 7629 if (!MethodDecl->isUsed(false)) 7630 DefineImplicitCopyAssignment(Loc, MethodDecl); 7631 } else if (MethodDecl->isVirtual()) 7632 MarkVTableUsed(Loc, MethodDecl->getParent()); 7633 } 7634 if (FunctionDecl *Function = dyn_cast<FunctionDecl>(D)) { 7635 // Implicit instantiation of function templates and member functions of 7636 // class templates. 7637 if (Function->isImplicitlyInstantiable()) { 7638 bool AlreadyInstantiated = false; 7639 if (FunctionTemplateSpecializationInfo *SpecInfo 7640 = Function->getTemplateSpecializationInfo()) { 7641 if (SpecInfo->getPointOfInstantiation().isInvalid()) 7642 SpecInfo->setPointOfInstantiation(Loc); 7643 else if (SpecInfo->getTemplateSpecializationKind() 7644 == TSK_ImplicitInstantiation) 7645 AlreadyInstantiated = true; 7646 } else if (MemberSpecializationInfo *MSInfo 7647 = Function->getMemberSpecializationInfo()) { 7648 if (MSInfo->getPointOfInstantiation().isInvalid()) 7649 MSInfo->setPointOfInstantiation(Loc); 7650 else if (MSInfo->getTemplateSpecializationKind() 7651 == TSK_ImplicitInstantiation) 7652 AlreadyInstantiated = true; 7653 } 7654 7655 if (!AlreadyInstantiated) { 7656 if (isa<CXXRecordDecl>(Function->getDeclContext()) && 7657 cast<CXXRecordDecl>(Function->getDeclContext())->isLocalClass()) 7658 PendingLocalImplicitInstantiations.push_back(std::make_pair(Function, 7659 Loc)); 7660 else 7661 PendingImplicitInstantiations.push_back(std::make_pair(Function, 7662 Loc)); 7663 } 7664 } 7665 7666 // FIXME: keep track of references to static functions 7667 Function->setUsed(true); 7668 7669 return; 7670 } 7671 7672 if (VarDecl *Var = dyn_cast<VarDecl>(D)) { 7673 // Implicit instantiation of static data members of class templates. 7674 if (Var->isStaticDataMember() && 7675 Var->getInstantiatedFromStaticDataMember()) { 7676 MemberSpecializationInfo *MSInfo = Var->getMemberSpecializationInfo(); 7677 assert(MSInfo && "Missing member specialization information?"); 7678 if (MSInfo->getPointOfInstantiation().isInvalid() && 7679 MSInfo->getTemplateSpecializationKind()== TSK_ImplicitInstantiation) { 7680 MSInfo->setPointOfInstantiation(Loc); 7681 PendingImplicitInstantiations.push_back(std::make_pair(Var, Loc)); 7682 } 7683 } 7684 7685 // FIXME: keep track of references to static data? 7686 7687 D->setUsed(true); 7688 return; 7689 } 7690} 7691 7692namespace { 7693 // Mark all of the declarations referenced 7694 // FIXME: Not fully implemented yet! We need to have a better understanding 7695 // of when we're entering 7696 class MarkReferencedDecls : public RecursiveASTVisitor<MarkReferencedDecls> { 7697 Sema &S; 7698 SourceLocation Loc; 7699 7700 public: 7701 typedef RecursiveASTVisitor<MarkReferencedDecls> Inherited; 7702 7703 MarkReferencedDecls(Sema &S, SourceLocation Loc) : S(S), Loc(Loc) { } 7704 7705 bool TraverseTemplateArgument(const TemplateArgument &Arg); 7706 bool TraverseRecordType(RecordType *T); 7707 }; 7708} 7709 7710bool MarkReferencedDecls::TraverseTemplateArgument( 7711 const TemplateArgument &Arg) { 7712 if (Arg.getKind() == TemplateArgument::Declaration) { 7713 S.MarkDeclarationReferenced(Loc, Arg.getAsDecl()); 7714 } 7715 7716 return Inherited::TraverseTemplateArgument(Arg); 7717} 7718 7719bool MarkReferencedDecls::TraverseRecordType(RecordType *T) { 7720 if (ClassTemplateSpecializationDecl *Spec 7721 = dyn_cast<ClassTemplateSpecializationDecl>(T->getDecl())) { 7722 const TemplateArgumentList &Args = Spec->getTemplateArgs(); 7723 return TraverseTemplateArguments(Args.getFlatArgumentList(), 7724 Args.flat_size()); 7725 } 7726 7727 return true; 7728} 7729 7730void Sema::MarkDeclarationsReferencedInType(SourceLocation Loc, QualType T) { 7731 MarkReferencedDecls Marker(*this, Loc); 7732 Marker.TraverseType(Context.getCanonicalType(T)); 7733} 7734 7735/// \brief Emit a diagnostic that describes an effect on the run-time behavior 7736/// of the program being compiled. 7737/// 7738/// This routine emits the given diagnostic when the code currently being 7739/// type-checked is "potentially evaluated", meaning that there is a 7740/// possibility that the code will actually be executable. Code in sizeof() 7741/// expressions, code used only during overload resolution, etc., are not 7742/// potentially evaluated. This routine will suppress such diagnostics or, 7743/// in the absolutely nutty case of potentially potentially evaluated 7744/// expressions (C++ typeid), queue the diagnostic to potentially emit it 7745/// later. 7746/// 7747/// This routine should be used for all diagnostics that describe the run-time 7748/// behavior of a program, such as passing a non-POD value through an ellipsis. 7749/// Failure to do so will likely result in spurious diagnostics or failures 7750/// during overload resolution or within sizeof/alignof/typeof/typeid. 7751bool Sema::DiagRuntimeBehavior(SourceLocation Loc, 7752 const PartialDiagnostic &PD) { 7753 switch (ExprEvalContexts.back().Context ) { 7754 case Unevaluated: 7755 // The argument will never be evaluated, so don't complain. 7756 break; 7757 7758 case PotentiallyEvaluated: 7759 Diag(Loc, PD); 7760 return true; 7761 7762 case PotentiallyPotentiallyEvaluated: 7763 ExprEvalContexts.back().addDiagnostic(Loc, PD); 7764 break; 7765 } 7766 7767 return false; 7768} 7769 7770bool Sema::CheckCallReturnType(QualType ReturnType, SourceLocation Loc, 7771 CallExpr *CE, FunctionDecl *FD) { 7772 if (ReturnType->isVoidType() || !ReturnType->isIncompleteType()) 7773 return false; 7774 7775 PartialDiagnostic Note = 7776 FD ? PDiag(diag::note_function_with_incomplete_return_type_declared_here) 7777 << FD->getDeclName() : PDiag(); 7778 SourceLocation NoteLoc = FD ? FD->getLocation() : SourceLocation(); 7779 7780 if (RequireCompleteType(Loc, ReturnType, 7781 FD ? 7782 PDiag(diag::err_call_function_incomplete_return) 7783 << CE->getSourceRange() << FD->getDeclName() : 7784 PDiag(diag::err_call_incomplete_return) 7785 << CE->getSourceRange(), 7786 std::make_pair(NoteLoc, Note))) 7787 return true; 7788 7789 return false; 7790} 7791 7792// Diagnose the common s/=/==/ typo. Note that adding parentheses 7793// will prevent this condition from triggering, which is what we want. 7794void Sema::DiagnoseAssignmentAsCondition(Expr *E) { 7795 SourceLocation Loc; 7796 7797 unsigned diagnostic = diag::warn_condition_is_assignment; 7798 7799 if (isa<BinaryOperator>(E)) { 7800 BinaryOperator *Op = cast<BinaryOperator>(E); 7801 if (Op->getOpcode() != BinaryOperator::Assign) 7802 return; 7803 7804 // Greylist some idioms by putting them into a warning subcategory. 7805 if (ObjCMessageExpr *ME 7806 = dyn_cast<ObjCMessageExpr>(Op->getRHS()->IgnoreParenCasts())) { 7807 Selector Sel = ME->getSelector(); 7808 7809 // self = [<foo> init...] 7810 if (isSelfExpr(Op->getLHS()) 7811 && Sel.getIdentifierInfoForSlot(0)->getName().startswith("init")) 7812 diagnostic = diag::warn_condition_is_idiomatic_assignment; 7813 7814 // <foo> = [<bar> nextObject] 7815 else if (Sel.isUnarySelector() && 7816 Sel.getIdentifierInfoForSlot(0)->getName() == "nextObject") 7817 diagnostic = diag::warn_condition_is_idiomatic_assignment; 7818 } 7819 7820 Loc = Op->getOperatorLoc(); 7821 } else if (isa<CXXOperatorCallExpr>(E)) { 7822 CXXOperatorCallExpr *Op = cast<CXXOperatorCallExpr>(E); 7823 if (Op->getOperator() != OO_Equal) 7824 return; 7825 7826 Loc = Op->getOperatorLoc(); 7827 } else { 7828 // Not an assignment. 7829 return; 7830 } 7831 7832 SourceLocation Open = E->getSourceRange().getBegin(); 7833 SourceLocation Close = PP.getLocForEndOfToken(E->getSourceRange().getEnd()); 7834 7835 Diag(Loc, diagnostic) << E->getSourceRange(); 7836 Diag(Loc, diag::note_condition_assign_to_comparison) 7837 << FixItHint::CreateReplacement(Loc, "=="); 7838 Diag(Loc, diag::note_condition_assign_silence) 7839 << FixItHint::CreateInsertion(Open, "(") 7840 << FixItHint::CreateInsertion(Close, ")"); 7841} 7842 7843bool Sema::CheckBooleanCondition(Expr *&E, SourceLocation Loc) { 7844 DiagnoseAssignmentAsCondition(E); 7845 7846 if (!E->isTypeDependent()) { 7847 DefaultFunctionArrayLvalueConversion(E); 7848 7849 QualType T = E->getType(); 7850 7851 if (getLangOptions().CPlusPlus) { 7852 if (CheckCXXBooleanCondition(E)) // C++ 6.4p4 7853 return true; 7854 } else if (!T->isScalarType()) { // C99 6.8.4.1p1 7855 Diag(Loc, diag::err_typecheck_statement_requires_scalar) 7856 << T << E->getSourceRange(); 7857 return true; 7858 } 7859 } 7860 7861 return false; 7862} 7863 7864Sema::OwningExprResult Sema::ActOnBooleanCondition(Scope *S, SourceLocation Loc, 7865 ExprArg SubExpr) { 7866 Expr *Sub = SubExpr.takeAs<Expr>(); 7867 if (!Sub) 7868 return ExprError(); 7869 7870 if (CheckBooleanCondition(Sub, Loc)) { 7871 Sub->Destroy(Context); 7872 return ExprError(); 7873 } 7874 7875 return Owned(Sub); 7876} 7877