SemaExpr.cpp revision 357f3b377abe85dd33a59122c90a361ea4226353
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/// getObjectForAnonymousRecordDecl - Retrieve the (unnamed) field or 500/// variable corresponding to the anonymous union or struct whose type 501/// is Record. 502static Decl *getObjectForAnonymousRecordDecl(ASTContext &Context, 503 RecordDecl *Record) { 504 assert(Record->isAnonymousStructOrUnion() && 505 "Record must be an anonymous struct or union!"); 506 507 // FIXME: Once Decls are directly linked together, this will be an O(1) 508 // operation rather than a slow walk through DeclContext's vector (which 509 // itself will be eliminated). DeclGroups might make this even better. 510 DeclContext *Ctx = Record->getDeclContext(); 511 for (DeclContext::decl_iterator D = Ctx->decls_begin(), 512 DEnd = Ctx->decls_end(); 513 D != DEnd; ++D) { 514 if (*D == Record) { 515 // The object for the anonymous struct/union directly 516 // follows its type in the list of declarations. 517 ++D; 518 assert(D != DEnd && "Missing object for anonymous record"); 519 assert(!cast<NamedDecl>(*D)->getDeclName() && "Decl should be unnamed"); 520 return *D; 521 } 522 } 523 524 assert(false && "Missing object for anonymous record"); 525 return 0; 526} 527 528/// \brief Given a field that represents a member of an anonymous 529/// struct/union, build the path from that field's context to the 530/// actual member. 531/// 532/// Construct the sequence of field member references we'll have to 533/// perform to get to the field in the anonymous union/struct. The 534/// list of members is built from the field outward, so traverse it 535/// backwards to go from an object in the current context to the field 536/// we found. 537/// 538/// \returns The variable from which the field access should begin, 539/// for an anonymous struct/union that is not a member of another 540/// class. Otherwise, returns NULL. 541VarDecl *Sema::BuildAnonymousStructUnionMemberPath(FieldDecl *Field, 542 llvm::SmallVectorImpl<FieldDecl *> &Path) { 543 assert(Field->getDeclContext()->isRecord() && 544 cast<RecordDecl>(Field->getDeclContext())->isAnonymousStructOrUnion() 545 && "Field must be stored inside an anonymous struct or union"); 546 547 Path.push_back(Field); 548 VarDecl *BaseObject = 0; 549 DeclContext *Ctx = Field->getDeclContext(); 550 do { 551 RecordDecl *Record = cast<RecordDecl>(Ctx); 552 Decl *AnonObject = getObjectForAnonymousRecordDecl(Context, Record); 553 if (FieldDecl *AnonField = dyn_cast<FieldDecl>(AnonObject)) 554 Path.push_back(AnonField); 555 else { 556 BaseObject = cast<VarDecl>(AnonObject); 557 break; 558 } 559 Ctx = Ctx->getParent(); 560 } while (Ctx->isRecord() && 561 cast<RecordDecl>(Ctx)->isAnonymousStructOrUnion()); 562 563 return BaseObject; 564} 565 566Sema::OwningExprResult 567Sema::BuildAnonymousStructUnionMemberReference(SourceLocation Loc, 568 FieldDecl *Field, 569 Expr *BaseObjectExpr, 570 SourceLocation OpLoc) { 571 llvm::SmallVector<FieldDecl *, 4> AnonFields; 572 VarDecl *BaseObject = BuildAnonymousStructUnionMemberPath(Field, 573 AnonFields); 574 575 // Build the expression that refers to the base object, from 576 // which we will build a sequence of member references to each 577 // of the anonymous union objects and, eventually, the field we 578 // found via name lookup. 579 bool BaseObjectIsPointer = false; 580 Qualifiers BaseQuals; 581 if (BaseObject) { 582 // BaseObject is an anonymous struct/union variable (and is, 583 // therefore, not part of another non-anonymous record). 584 if (BaseObjectExpr) BaseObjectExpr->Destroy(Context); 585 MarkDeclarationReferenced(Loc, BaseObject); 586 BaseObjectExpr = new (Context) DeclRefExpr(BaseObject,BaseObject->getType(), 587 SourceLocation()); 588 BaseQuals 589 = Context.getCanonicalType(BaseObject->getType()).getQualifiers(); 590 } else if (BaseObjectExpr) { 591 // The caller provided the base object expression. Determine 592 // whether its a pointer and whether it adds any qualifiers to the 593 // anonymous struct/union fields we're looking into. 594 QualType ObjectType = BaseObjectExpr->getType(); 595 if (const PointerType *ObjectPtr = ObjectType->getAs<PointerType>()) { 596 BaseObjectIsPointer = true; 597 ObjectType = ObjectPtr->getPointeeType(); 598 } 599 BaseQuals 600 = Context.getCanonicalType(ObjectType).getQualifiers(); 601 } else { 602 // We've found a member of an anonymous struct/union that is 603 // inside a non-anonymous struct/union, so in a well-formed 604 // program our base object expression is "this". 605 DeclContext *DC = getFunctionLevelDeclContext(); 606 if (CXXMethodDecl *MD = dyn_cast<CXXMethodDecl>(DC)) { 607 if (!MD->isStatic()) { 608 QualType AnonFieldType 609 = Context.getTagDeclType( 610 cast<RecordDecl>(AnonFields.back()->getDeclContext())); 611 QualType ThisType = Context.getTagDeclType(MD->getParent()); 612 if ((Context.getCanonicalType(AnonFieldType) 613 == Context.getCanonicalType(ThisType)) || 614 IsDerivedFrom(ThisType, AnonFieldType)) { 615 // Our base object expression is "this". 616 BaseObjectExpr = new (Context) CXXThisExpr(Loc, 617 MD->getThisType(Context), 618 /*isImplicit=*/true); 619 BaseObjectIsPointer = true; 620 } 621 } else { 622 return ExprError(Diag(Loc,diag::err_invalid_member_use_in_static_method) 623 << Field->getDeclName()); 624 } 625 BaseQuals = Qualifiers::fromCVRMask(MD->getTypeQualifiers()); 626 } 627 628 if (!BaseObjectExpr) 629 return ExprError(Diag(Loc, diag::err_invalid_non_static_member_use) 630 << Field->getDeclName()); 631 } 632 633 // Build the implicit member references to the field of the 634 // anonymous struct/union. 635 Expr *Result = BaseObjectExpr; 636 Qualifiers ResultQuals = BaseQuals; 637 for (llvm::SmallVector<FieldDecl *, 4>::reverse_iterator 638 FI = AnonFields.rbegin(), FIEnd = AnonFields.rend(); 639 FI != FIEnd; ++FI) { 640 QualType MemberType = (*FI)->getType(); 641 Qualifiers MemberTypeQuals = 642 Context.getCanonicalType(MemberType).getQualifiers(); 643 644 // CVR attributes from the base are picked up by members, 645 // except that 'mutable' members don't pick up 'const'. 646 if ((*FI)->isMutable()) 647 ResultQuals.removeConst(); 648 649 // GC attributes are never picked up by members. 650 ResultQuals.removeObjCGCAttr(); 651 652 // TR 18037 does not allow fields to be declared with address spaces. 653 assert(!MemberTypeQuals.hasAddressSpace()); 654 655 Qualifiers NewQuals = ResultQuals + MemberTypeQuals; 656 if (NewQuals != MemberTypeQuals) 657 MemberType = Context.getQualifiedType(MemberType, NewQuals); 658 659 MarkDeclarationReferenced(Loc, *FI); 660 PerformObjectMemberConversion(Result, /*FIXME:Qualifier=*/0, *FI, *FI); 661 // FIXME: Might this end up being a qualified name? 662 Result = new (Context) MemberExpr(Result, BaseObjectIsPointer, *FI, 663 OpLoc, MemberType); 664 BaseObjectIsPointer = false; 665 ResultQuals = NewQuals; 666 } 667 668 return Owned(Result); 669} 670 671/// Decomposes the given name into a DeclarationName, its location, and 672/// possibly a list of template arguments. 673/// 674/// If this produces template arguments, it is permitted to call 675/// DecomposeTemplateName. 676/// 677/// This actually loses a lot of source location information for 678/// non-standard name kinds; we should consider preserving that in 679/// some way. 680static void DecomposeUnqualifiedId(Sema &SemaRef, 681 const UnqualifiedId &Id, 682 TemplateArgumentListInfo &Buffer, 683 DeclarationName &Name, 684 SourceLocation &NameLoc, 685 const TemplateArgumentListInfo *&TemplateArgs) { 686 if (Id.getKind() == UnqualifiedId::IK_TemplateId) { 687 Buffer.setLAngleLoc(Id.TemplateId->LAngleLoc); 688 Buffer.setRAngleLoc(Id.TemplateId->RAngleLoc); 689 690 ASTTemplateArgsPtr TemplateArgsPtr(SemaRef, 691 Id.TemplateId->getTemplateArgs(), 692 Id.TemplateId->NumArgs); 693 SemaRef.translateTemplateArguments(TemplateArgsPtr, Buffer); 694 TemplateArgsPtr.release(); 695 696 TemplateName TName = 697 Sema::TemplateTy::make(Id.TemplateId->Template).getAsVal<TemplateName>(); 698 699 Name = SemaRef.Context.getNameForTemplate(TName); 700 NameLoc = Id.TemplateId->TemplateNameLoc; 701 TemplateArgs = &Buffer; 702 } else { 703 Name = SemaRef.GetNameFromUnqualifiedId(Id); 704 NameLoc = Id.StartLocation; 705 TemplateArgs = 0; 706 } 707} 708 709/// Decompose the given template name into a list of lookup results. 710/// 711/// The unqualified ID must name a non-dependent template, which can 712/// be more easily tested by checking whether DecomposeUnqualifiedId 713/// found template arguments. 714static void DecomposeTemplateName(LookupResult &R, const UnqualifiedId &Id) { 715 assert(Id.getKind() == UnqualifiedId::IK_TemplateId); 716 TemplateName TName = 717 Sema::TemplateTy::make(Id.TemplateId->Template).getAsVal<TemplateName>(); 718 719 if (TemplateDecl *TD = TName.getAsTemplateDecl()) 720 R.addDecl(TD); 721 else if (OverloadedTemplateStorage *OT = TName.getAsOverloadedTemplate()) 722 for (OverloadedTemplateStorage::iterator I = OT->begin(), E = OT->end(); 723 I != E; ++I) 724 R.addDecl(*I); 725 726 R.resolveKind(); 727} 728 729/// Determines whether the given record is "fully-formed" at the given 730/// location, i.e. whether a qualified lookup into it is assured of 731/// getting consistent results already. 732static bool IsFullyFormedScope(Sema &SemaRef, CXXRecordDecl *Record) { 733 if (!Record->hasDefinition()) 734 return false; 735 736 for (CXXRecordDecl::base_class_iterator I = Record->bases_begin(), 737 E = Record->bases_end(); I != E; ++I) { 738 CanQualType BaseT = SemaRef.Context.getCanonicalType((*I).getType()); 739 CanQual<RecordType> BaseRT = BaseT->getAs<RecordType>(); 740 if (!BaseRT) return false; 741 742 CXXRecordDecl *BaseRecord = cast<CXXRecordDecl>(BaseRT->getDecl()); 743 if (!BaseRecord->hasDefinition() || 744 !IsFullyFormedScope(SemaRef, BaseRecord)) 745 return false; 746 } 747 748 return true; 749} 750 751/// Determines whether we can lookup this id-expression now or whether 752/// we have to wait until template instantiation is complete. 753static bool IsDependentIdExpression(Sema &SemaRef, const CXXScopeSpec &SS) { 754 DeclContext *DC = SemaRef.computeDeclContext(SS, false); 755 756 // If the qualifier scope isn't computable, it's definitely dependent. 757 if (!DC) return true; 758 759 // If the qualifier scope doesn't name a record, we can always look into it. 760 if (!isa<CXXRecordDecl>(DC)) return false; 761 762 // We can't look into record types unless they're fully-formed. 763 if (!IsFullyFormedScope(SemaRef, cast<CXXRecordDecl>(DC))) return true; 764 765 return false; 766} 767 768/// Determines if the given class is provably not derived from all of 769/// the prospective base classes. 770static bool IsProvablyNotDerivedFrom(Sema &SemaRef, 771 CXXRecordDecl *Record, 772 const llvm::SmallPtrSet<CXXRecordDecl*, 4> &Bases) { 773 if (Bases.count(Record->getCanonicalDecl())) 774 return false; 775 776 RecordDecl *RD = Record->getDefinition(); 777 if (!RD) return false; 778 Record = cast<CXXRecordDecl>(RD); 779 780 for (CXXRecordDecl::base_class_iterator I = Record->bases_begin(), 781 E = Record->bases_end(); I != E; ++I) { 782 CanQualType BaseT = SemaRef.Context.getCanonicalType((*I).getType()); 783 CanQual<RecordType> BaseRT = BaseT->getAs<RecordType>(); 784 if (!BaseRT) return false; 785 786 CXXRecordDecl *BaseRecord = cast<CXXRecordDecl>(BaseRT->getDecl()); 787 if (!IsProvablyNotDerivedFrom(SemaRef, BaseRecord, Bases)) 788 return false; 789 } 790 791 return true; 792} 793 794enum IMAKind { 795 /// The reference is definitely not an instance member access. 796 IMA_Static, 797 798 /// The reference may be an implicit instance member access. 799 IMA_Mixed, 800 801 /// The reference may be to an instance member, but it is invalid if 802 /// so, because the context is not an instance method. 803 IMA_Mixed_StaticContext, 804 805 /// The reference may be to an instance member, but it is invalid if 806 /// so, because the context is from an unrelated class. 807 IMA_Mixed_Unrelated, 808 809 /// The reference is definitely an implicit instance member access. 810 IMA_Instance, 811 812 /// The reference may be to an unresolved using declaration. 813 IMA_Unresolved, 814 815 /// The reference may be to an unresolved using declaration and the 816 /// context is not an instance method. 817 IMA_Unresolved_StaticContext, 818 819 /// The reference is to a member of an anonymous structure in a 820 /// non-class context. 821 IMA_AnonymousMember, 822 823 /// All possible referrents are instance members and the current 824 /// context is not an instance method. 825 IMA_Error_StaticContext, 826 827 /// All possible referrents are instance members of an unrelated 828 /// class. 829 IMA_Error_Unrelated 830}; 831 832/// The given lookup names class member(s) and is not being used for 833/// an address-of-member expression. Classify the type of access 834/// according to whether it's possible that this reference names an 835/// instance member. This is best-effort; it is okay to 836/// conservatively answer "yes", in which case some errors will simply 837/// not be caught until template-instantiation. 838static IMAKind ClassifyImplicitMemberAccess(Sema &SemaRef, 839 const LookupResult &R) { 840 assert(!R.empty() && (*R.begin())->isCXXClassMember()); 841 842 DeclContext *DC = SemaRef.getFunctionLevelDeclContext(); 843 bool isStaticContext = 844 (!isa<CXXMethodDecl>(DC) || 845 cast<CXXMethodDecl>(DC)->isStatic()); 846 847 if (R.isUnresolvableResult()) 848 return isStaticContext ? IMA_Unresolved_StaticContext : IMA_Unresolved; 849 850 // Collect all the declaring classes of instance members we find. 851 bool hasNonInstance = false; 852 llvm::SmallPtrSet<CXXRecordDecl*, 4> Classes; 853 for (LookupResult::iterator I = R.begin(), E = R.end(); I != E; ++I) { 854 NamedDecl *D = *I; 855 if (D->isCXXInstanceMember()) { 856 CXXRecordDecl *R = cast<CXXRecordDecl>(D->getDeclContext()); 857 858 // If this is a member of an anonymous record, move out to the 859 // innermost non-anonymous struct or union. If there isn't one, 860 // that's a special case. 861 while (R->isAnonymousStructOrUnion()) { 862 R = dyn_cast<CXXRecordDecl>(R->getParent()); 863 if (!R) return IMA_AnonymousMember; 864 } 865 Classes.insert(R->getCanonicalDecl()); 866 } 867 else 868 hasNonInstance = true; 869 } 870 871 // If we didn't find any instance members, it can't be an implicit 872 // member reference. 873 if (Classes.empty()) 874 return IMA_Static; 875 876 // If the current context is not an instance method, it can't be 877 // an implicit member reference. 878 if (isStaticContext) 879 return (hasNonInstance ? IMA_Mixed_StaticContext : IMA_Error_StaticContext); 880 881 // If we can prove that the current context is unrelated to all the 882 // declaring classes, it can't be an implicit member reference (in 883 // which case it's an error if any of those members are selected). 884 if (IsProvablyNotDerivedFrom(SemaRef, 885 cast<CXXMethodDecl>(DC)->getParent(), 886 Classes)) 887 return (hasNonInstance ? IMA_Mixed_Unrelated : IMA_Error_Unrelated); 888 889 return (hasNonInstance ? IMA_Mixed : IMA_Instance); 890} 891 892/// Diagnose a reference to a field with no object available. 893static void DiagnoseInstanceReference(Sema &SemaRef, 894 const CXXScopeSpec &SS, 895 const LookupResult &R) { 896 SourceLocation Loc = R.getNameLoc(); 897 SourceRange Range(Loc); 898 if (SS.isSet()) Range.setBegin(SS.getRange().getBegin()); 899 900 if (R.getAsSingle<FieldDecl>()) { 901 if (CXXMethodDecl *MD = dyn_cast<CXXMethodDecl>(SemaRef.CurContext)) { 902 if (MD->isStatic()) { 903 // "invalid use of member 'x' in static member function" 904 SemaRef.Diag(Loc, diag::err_invalid_member_use_in_static_method) 905 << Range << R.getLookupName(); 906 return; 907 } 908 } 909 910 SemaRef.Diag(Loc, diag::err_invalid_non_static_member_use) 911 << R.getLookupName() << Range; 912 return; 913 } 914 915 SemaRef.Diag(Loc, diag::err_member_call_without_object) << Range; 916} 917 918/// Diagnose an empty lookup. 919/// 920/// \return false if new lookup candidates were found 921bool Sema::DiagnoseEmptyLookup(Scope *S, CXXScopeSpec &SS, 922 LookupResult &R, CorrectTypoContext CTC) { 923 DeclarationName Name = R.getLookupName(); 924 925 unsigned diagnostic = diag::err_undeclared_var_use; 926 unsigned diagnostic_suggest = diag::err_undeclared_var_use_suggest; 927 if (Name.getNameKind() == DeclarationName::CXXOperatorName || 928 Name.getNameKind() == DeclarationName::CXXLiteralOperatorName || 929 Name.getNameKind() == DeclarationName::CXXConversionFunctionName) { 930 diagnostic = diag::err_undeclared_use; 931 diagnostic_suggest = diag::err_undeclared_use_suggest; 932 } 933 934 // If the original lookup was an unqualified lookup, fake an 935 // unqualified lookup. This is useful when (for example) the 936 // original lookup would not have found something because it was a 937 // dependent name. 938 for (DeclContext *DC = SS.isEmpty()? CurContext : 0; 939 DC; DC = DC->getParent()) { 940 if (isa<CXXRecordDecl>(DC)) { 941 LookupQualifiedName(R, DC); 942 943 if (!R.empty()) { 944 // Don't give errors about ambiguities in this lookup. 945 R.suppressDiagnostics(); 946 947 CXXMethodDecl *CurMethod = dyn_cast<CXXMethodDecl>(CurContext); 948 bool isInstance = CurMethod && 949 CurMethod->isInstance() && 950 DC == CurMethod->getParent(); 951 952 // Give a code modification hint to insert 'this->'. 953 // TODO: fixit for inserting 'Base<T>::' in the other cases. 954 // Actually quite difficult! 955 if (isInstance) 956 Diag(R.getNameLoc(), diagnostic) << Name 957 << FixItHint::CreateInsertion(R.getNameLoc(), "this->"); 958 else 959 Diag(R.getNameLoc(), diagnostic) << Name; 960 961 // Do we really want to note all of these? 962 for (LookupResult::iterator I = R.begin(), E = R.end(); I != E; ++I) 963 Diag((*I)->getLocation(), diag::note_dependent_var_use); 964 965 // Tell the callee to try to recover. 966 return false; 967 } 968 } 969 } 970 971 // We didn't find anything, so try to correct for a typo. 972 DeclarationName Corrected; 973 if (S && (Corrected = CorrectTypo(R, S, &SS, false, CTC))) { 974 if (!R.empty()) { 975 if (isa<ValueDecl>(*R.begin()) || isa<FunctionTemplateDecl>(*R.begin())) { 976 if (SS.isEmpty()) 977 Diag(R.getNameLoc(), diagnostic_suggest) << Name << R.getLookupName() 978 << FixItHint::CreateReplacement(R.getNameLoc(), 979 R.getLookupName().getAsString()); 980 else 981 Diag(R.getNameLoc(), diag::err_no_member_suggest) 982 << Name << computeDeclContext(SS, false) << R.getLookupName() 983 << SS.getRange() 984 << FixItHint::CreateReplacement(R.getNameLoc(), 985 R.getLookupName().getAsString()); 986 if (NamedDecl *ND = R.getAsSingle<NamedDecl>()) 987 Diag(ND->getLocation(), diag::note_previous_decl) 988 << ND->getDeclName(); 989 990 // Tell the callee to try to recover. 991 return false; 992 } 993 994 if (isa<TypeDecl>(*R.begin()) || isa<ObjCInterfaceDecl>(*R.begin())) { 995 // FIXME: If we ended up with a typo for a type name or 996 // Objective-C class name, we're in trouble because the parser 997 // is in the wrong place to recover. Suggest the typo 998 // correction, but don't make it a fix-it since we're not going 999 // to recover well anyway. 1000 if (SS.isEmpty()) 1001 Diag(R.getNameLoc(), diagnostic_suggest) << Name << R.getLookupName(); 1002 else 1003 Diag(R.getNameLoc(), diag::err_no_member_suggest) 1004 << Name << computeDeclContext(SS, false) << R.getLookupName() 1005 << SS.getRange(); 1006 1007 // Don't try to recover; it won't work. 1008 return true; 1009 } 1010 } else { 1011 // FIXME: We found a keyword. Suggest it, but don't provide a fix-it 1012 // because we aren't able to recover. 1013 if (SS.isEmpty()) 1014 Diag(R.getNameLoc(), diagnostic_suggest) << Name << Corrected; 1015 else 1016 Diag(R.getNameLoc(), diag::err_no_member_suggest) 1017 << Name << computeDeclContext(SS, false) << Corrected 1018 << SS.getRange(); 1019 return true; 1020 } 1021 R.clear(); 1022 } 1023 1024 // Emit a special diagnostic for failed member lookups. 1025 // FIXME: computing the declaration context might fail here (?) 1026 if (!SS.isEmpty()) { 1027 Diag(R.getNameLoc(), diag::err_no_member) 1028 << Name << computeDeclContext(SS, false) 1029 << SS.getRange(); 1030 return true; 1031 } 1032 1033 // Give up, we can't recover. 1034 Diag(R.getNameLoc(), diagnostic) << Name; 1035 return true; 1036} 1037 1038Sema::OwningExprResult Sema::ActOnIdExpression(Scope *S, 1039 CXXScopeSpec &SS, 1040 UnqualifiedId &Id, 1041 bool HasTrailingLParen, 1042 bool isAddressOfOperand) { 1043 assert(!(isAddressOfOperand && HasTrailingLParen) && 1044 "cannot be direct & operand and have a trailing lparen"); 1045 1046 if (SS.isInvalid()) 1047 return ExprError(); 1048 1049 TemplateArgumentListInfo TemplateArgsBuffer; 1050 1051 // Decompose the UnqualifiedId into the following data. 1052 DeclarationName Name; 1053 SourceLocation NameLoc; 1054 const TemplateArgumentListInfo *TemplateArgs; 1055 DecomposeUnqualifiedId(*this, Id, TemplateArgsBuffer, 1056 Name, NameLoc, TemplateArgs); 1057 1058 IdentifierInfo *II = Name.getAsIdentifierInfo(); 1059 1060 // C++ [temp.dep.expr]p3: 1061 // An id-expression is type-dependent if it contains: 1062 // -- an identifier that was declared with a dependent type, 1063 // (note: handled after lookup) 1064 // -- a template-id that is dependent, 1065 // (note: handled in BuildTemplateIdExpr) 1066 // -- a conversion-function-id that specifies a dependent type, 1067 // -- a nested-name-specifier that contains a class-name that 1068 // names a dependent type. 1069 // Determine whether this is a member of an unknown specialization; 1070 // we need to handle these differently. 1071 if ((Name.getNameKind() == DeclarationName::CXXConversionFunctionName && 1072 Name.getCXXNameType()->isDependentType()) || 1073 (SS.isSet() && IsDependentIdExpression(*this, SS))) { 1074 return ActOnDependentIdExpression(SS, Name, NameLoc, 1075 isAddressOfOperand, 1076 TemplateArgs); 1077 } 1078 1079 // Perform the required lookup. 1080 LookupResult R(*this, Name, NameLoc, LookupOrdinaryName); 1081 if (TemplateArgs) { 1082 // Just re-use the lookup done by isTemplateName. 1083 DecomposeTemplateName(R, Id); 1084 1085 // Re-derive the naming class. 1086 if (SS.isSet()) { 1087 NestedNameSpecifier *Qualifier 1088 = static_cast<NestedNameSpecifier *>(SS.getScopeRep()); 1089 if (const Type *Ty = Qualifier->getAsType()) 1090 if (CXXRecordDecl *NamingClass = Ty->getAsCXXRecordDecl()) 1091 R.setNamingClass(NamingClass); 1092 } 1093 } else { 1094 bool IvarLookupFollowUp = (!SS.isSet() && II && getCurMethodDecl()); 1095 LookupParsedName(R, S, &SS, !IvarLookupFollowUp); 1096 1097 // If this reference is in an Objective-C method, then we need to do 1098 // some special Objective-C lookup, too. 1099 if (IvarLookupFollowUp) { 1100 OwningExprResult E(LookupInObjCMethod(R, S, II, true)); 1101 if (E.isInvalid()) 1102 return ExprError(); 1103 1104 Expr *Ex = E.takeAs<Expr>(); 1105 if (Ex) return Owned(Ex); 1106 } 1107 } 1108 1109 if (R.isAmbiguous()) 1110 return ExprError(); 1111 1112 // Determine whether this name might be a candidate for 1113 // argument-dependent lookup. 1114 bool ADL = UseArgumentDependentLookup(SS, R, HasTrailingLParen); 1115 1116 if (R.empty() && !ADL) { 1117 // Otherwise, this could be an implicitly declared function reference (legal 1118 // in C90, extension in C99, forbidden in C++). 1119 if (HasTrailingLParen && II && !getLangOptions().CPlusPlus) { 1120 NamedDecl *D = ImplicitlyDefineFunction(NameLoc, *II, S); 1121 if (D) R.addDecl(D); 1122 } 1123 1124 // If this name wasn't predeclared and if this is not a function 1125 // call, diagnose the problem. 1126 if (R.empty()) { 1127 if (DiagnoseEmptyLookup(S, SS, R, CTC_Unknown)) 1128 return ExprError(); 1129 1130 assert(!R.empty() && 1131 "DiagnoseEmptyLookup returned false but added no results"); 1132 1133 // If we found an Objective-C instance variable, let 1134 // LookupInObjCMethod build the appropriate expression to 1135 // reference the ivar. 1136 if (ObjCIvarDecl *Ivar = R.getAsSingle<ObjCIvarDecl>()) { 1137 R.clear(); 1138 OwningExprResult E(LookupInObjCMethod(R, S, Ivar->getIdentifier())); 1139 assert(E.isInvalid() || E.get()); 1140 return move(E); 1141 } 1142 } 1143 } 1144 1145 // This is guaranteed from this point on. 1146 assert(!R.empty() || ADL); 1147 1148 if (VarDecl *Var = R.getAsSingle<VarDecl>()) { 1149 // Warn about constructs like: 1150 // if (void *X = foo()) { ... } else { X }. 1151 // In the else block, the pointer is always false. 1152 if (Var->isDeclaredInCondition() && Var->getType()->isScalarType()) { 1153 Scope *CheckS = S; 1154 while (CheckS && CheckS->getControlParent()) { 1155 if ((CheckS->getFlags() & Scope::ElseScope) && 1156 CheckS->getControlParent()->isDeclScope(DeclPtrTy::make(Var))) { 1157 ExprError(Diag(NameLoc, diag::warn_value_always_zero) 1158 << Var->getDeclName() 1159 << (Var->getType()->isPointerType() ? 2 : 1160 Var->getType()->isBooleanType() ? 1 : 0)); 1161 break; 1162 } 1163 1164 // Move to the parent of this scope. 1165 CheckS = CheckS->getParent(); 1166 } 1167 } 1168 } else if (FunctionDecl *Func = R.getAsSingle<FunctionDecl>()) { 1169 if (!getLangOptions().CPlusPlus && !Func->hasPrototype()) { 1170 // C99 DR 316 says that, if a function type comes from a 1171 // function definition (without a prototype), that type is only 1172 // used for checking compatibility. Therefore, when referencing 1173 // the function, we pretend that we don't have the full function 1174 // type. 1175 if (DiagnoseUseOfDecl(Func, NameLoc)) 1176 return ExprError(); 1177 1178 QualType T = Func->getType(); 1179 QualType NoProtoType = T; 1180 if (const FunctionProtoType *Proto = T->getAs<FunctionProtoType>()) 1181 NoProtoType = Context.getFunctionNoProtoType(Proto->getResultType(), 1182 Proto->getExtInfo()); 1183 return BuildDeclRefExpr(Func, NoProtoType, NameLoc, &SS); 1184 } 1185 } 1186 1187 // Check whether this might be a C++ implicit instance member access. 1188 // C++ [expr.prim.general]p6: 1189 // Within the definition of a non-static member function, an 1190 // identifier that names a non-static member is transformed to a 1191 // class member access expression. 1192 // But note that &SomeClass::foo is grammatically distinct, even 1193 // though we don't parse it that way. 1194 if (!R.empty() && (*R.begin())->isCXXClassMember()) { 1195 bool isAbstractMemberPointer = (isAddressOfOperand && !SS.isEmpty()); 1196 if (!isAbstractMemberPointer) 1197 return BuildPossibleImplicitMemberExpr(SS, R, TemplateArgs); 1198 } 1199 1200 if (TemplateArgs) 1201 return BuildTemplateIdExpr(SS, R, ADL, *TemplateArgs); 1202 1203 return BuildDeclarationNameExpr(SS, R, ADL); 1204} 1205 1206/// Builds an expression which might be an implicit member expression. 1207Sema::OwningExprResult 1208Sema::BuildPossibleImplicitMemberExpr(const CXXScopeSpec &SS, 1209 LookupResult &R, 1210 const TemplateArgumentListInfo *TemplateArgs) { 1211 switch (ClassifyImplicitMemberAccess(*this, R)) { 1212 case IMA_Instance: 1213 return BuildImplicitMemberExpr(SS, R, TemplateArgs, true); 1214 1215 case IMA_AnonymousMember: 1216 assert(R.isSingleResult()); 1217 return BuildAnonymousStructUnionMemberReference(R.getNameLoc(), 1218 R.getAsSingle<FieldDecl>()); 1219 1220 case IMA_Mixed: 1221 case IMA_Mixed_Unrelated: 1222 case IMA_Unresolved: 1223 return BuildImplicitMemberExpr(SS, R, TemplateArgs, false); 1224 1225 case IMA_Static: 1226 case IMA_Mixed_StaticContext: 1227 case IMA_Unresolved_StaticContext: 1228 if (TemplateArgs) 1229 return BuildTemplateIdExpr(SS, R, false, *TemplateArgs); 1230 return BuildDeclarationNameExpr(SS, R, false); 1231 1232 case IMA_Error_StaticContext: 1233 case IMA_Error_Unrelated: 1234 DiagnoseInstanceReference(*this, SS, R); 1235 return ExprError(); 1236 } 1237 1238 llvm_unreachable("unexpected instance member access kind"); 1239 return ExprError(); 1240} 1241 1242/// BuildQualifiedDeclarationNameExpr - Build a C++ qualified 1243/// declaration name, generally during template instantiation. 1244/// There's a large number of things which don't need to be done along 1245/// this path. 1246Sema::OwningExprResult 1247Sema::BuildQualifiedDeclarationNameExpr(CXXScopeSpec &SS, 1248 DeclarationName Name, 1249 SourceLocation NameLoc) { 1250 DeclContext *DC; 1251 if (!(DC = computeDeclContext(SS, false)) || DC->isDependentContext()) 1252 return BuildDependentDeclRefExpr(SS, Name, NameLoc, 0); 1253 1254 if (RequireCompleteDeclContext(SS, DC)) 1255 return ExprError(); 1256 1257 LookupResult R(*this, Name, NameLoc, LookupOrdinaryName); 1258 LookupQualifiedName(R, DC); 1259 1260 if (R.isAmbiguous()) 1261 return ExprError(); 1262 1263 if (R.empty()) { 1264 Diag(NameLoc, diag::err_no_member) << Name << DC << SS.getRange(); 1265 return ExprError(); 1266 } 1267 1268 return BuildDeclarationNameExpr(SS, R, /*ADL*/ false); 1269} 1270 1271/// LookupInObjCMethod - The parser has read a name in, and Sema has 1272/// detected that we're currently inside an ObjC method. Perform some 1273/// additional lookup. 1274/// 1275/// Ideally, most of this would be done by lookup, but there's 1276/// actually quite a lot of extra work involved. 1277/// 1278/// Returns a null sentinel to indicate trivial success. 1279Sema::OwningExprResult 1280Sema::LookupInObjCMethod(LookupResult &Lookup, Scope *S, 1281 IdentifierInfo *II, bool AllowBuiltinCreation) { 1282 SourceLocation Loc = Lookup.getNameLoc(); 1283 ObjCMethodDecl *CurMethod = getCurMethodDecl(); 1284 1285 // There are two cases to handle here. 1) scoped lookup could have failed, 1286 // in which case we should look for an ivar. 2) scoped lookup could have 1287 // found a decl, but that decl is outside the current instance method (i.e. 1288 // a global variable). In these two cases, we do a lookup for an ivar with 1289 // this name, if the lookup sucedes, we replace it our current decl. 1290 1291 // If we're in a class method, we don't normally want to look for 1292 // ivars. But if we don't find anything else, and there's an 1293 // ivar, that's an error. 1294 bool IsClassMethod = CurMethod->isClassMethod(); 1295 1296 bool LookForIvars; 1297 if (Lookup.empty()) 1298 LookForIvars = true; 1299 else if (IsClassMethod) 1300 LookForIvars = false; 1301 else 1302 LookForIvars = (Lookup.isSingleResult() && 1303 Lookup.getFoundDecl()->isDefinedOutsideFunctionOrMethod()); 1304 ObjCInterfaceDecl *IFace = 0; 1305 if (LookForIvars) { 1306 IFace = CurMethod->getClassInterface(); 1307 ObjCInterfaceDecl *ClassDeclared; 1308 if (ObjCIvarDecl *IV = IFace->lookupInstanceVariable(II, ClassDeclared)) { 1309 // Diagnose using an ivar in a class method. 1310 if (IsClassMethod) 1311 return ExprError(Diag(Loc, diag::error_ivar_use_in_class_method) 1312 << IV->getDeclName()); 1313 1314 // If we're referencing an invalid decl, just return this as a silent 1315 // error node. The error diagnostic was already emitted on the decl. 1316 if (IV->isInvalidDecl()) 1317 return ExprError(); 1318 1319 // Check if referencing a field with __attribute__((deprecated)). 1320 if (DiagnoseUseOfDecl(IV, Loc)) 1321 return ExprError(); 1322 1323 // Diagnose the use of an ivar outside of the declaring class. 1324 if (IV->getAccessControl() == ObjCIvarDecl::Private && 1325 ClassDeclared != IFace) 1326 Diag(Loc, diag::error_private_ivar_access) << IV->getDeclName(); 1327 1328 // FIXME: This should use a new expr for a direct reference, don't 1329 // turn this into Self->ivar, just return a BareIVarExpr or something. 1330 IdentifierInfo &II = Context.Idents.get("self"); 1331 UnqualifiedId SelfName; 1332 SelfName.setIdentifier(&II, SourceLocation()); 1333 CXXScopeSpec SelfScopeSpec; 1334 OwningExprResult SelfExpr = ActOnIdExpression(S, SelfScopeSpec, 1335 SelfName, false, false); 1336 MarkDeclarationReferenced(Loc, IV); 1337 return Owned(new (Context) 1338 ObjCIvarRefExpr(IV, IV->getType(), Loc, 1339 SelfExpr.takeAs<Expr>(), true, true)); 1340 } 1341 } else if (CurMethod->isInstanceMethod()) { 1342 // We should warn if a local variable hides an ivar. 1343 ObjCInterfaceDecl *IFace = CurMethod->getClassInterface(); 1344 ObjCInterfaceDecl *ClassDeclared; 1345 if (ObjCIvarDecl *IV = IFace->lookupInstanceVariable(II, ClassDeclared)) { 1346 if (IV->getAccessControl() != ObjCIvarDecl::Private || 1347 IFace == ClassDeclared) 1348 Diag(Loc, diag::warn_ivar_use_hidden) << IV->getDeclName(); 1349 } 1350 } 1351 1352 if (Lookup.empty() && II && AllowBuiltinCreation) { 1353 // FIXME. Consolidate this with similar code in LookupName. 1354 if (unsigned BuiltinID = II->getBuiltinID()) { 1355 if (!(getLangOptions().CPlusPlus && 1356 Context.BuiltinInfo.isPredefinedLibFunction(BuiltinID))) { 1357 NamedDecl *D = LazilyCreateBuiltin((IdentifierInfo *)II, BuiltinID, 1358 S, Lookup.isForRedeclaration(), 1359 Lookup.getNameLoc()); 1360 if (D) Lookup.addDecl(D); 1361 } 1362 } 1363 } 1364 // Sentinel value saying that we didn't do anything special. 1365 return Owned((Expr*) 0); 1366} 1367 1368/// \brief Cast a base object to a member's actual type. 1369/// 1370/// Logically this happens in three phases: 1371/// 1372/// * First we cast from the base type to the naming class. 1373/// The naming class is the class into which we were looking 1374/// when we found the member; it's the qualifier type if a 1375/// qualifier was provided, and otherwise it's the base type. 1376/// 1377/// * Next we cast from the naming class to the declaring class. 1378/// If the member we found was brought into a class's scope by 1379/// a using declaration, this is that class; otherwise it's 1380/// the class declaring the member. 1381/// 1382/// * Finally we cast from the declaring class to the "true" 1383/// declaring class of the member. This conversion does not 1384/// obey access control. 1385bool 1386Sema::PerformObjectMemberConversion(Expr *&From, 1387 NestedNameSpecifier *Qualifier, 1388 NamedDecl *FoundDecl, 1389 NamedDecl *Member) { 1390 CXXRecordDecl *RD = dyn_cast<CXXRecordDecl>(Member->getDeclContext()); 1391 if (!RD) 1392 return false; 1393 1394 QualType DestRecordType; 1395 QualType DestType; 1396 QualType FromRecordType; 1397 QualType FromType = From->getType(); 1398 bool PointerConversions = false; 1399 if (isa<FieldDecl>(Member)) { 1400 DestRecordType = Context.getCanonicalType(Context.getTypeDeclType(RD)); 1401 1402 if (FromType->getAs<PointerType>()) { 1403 DestType = Context.getPointerType(DestRecordType); 1404 FromRecordType = FromType->getPointeeType(); 1405 PointerConversions = true; 1406 } else { 1407 DestType = DestRecordType; 1408 FromRecordType = FromType; 1409 } 1410 } else if (CXXMethodDecl *Method = dyn_cast<CXXMethodDecl>(Member)) { 1411 if (Method->isStatic()) 1412 return false; 1413 1414 DestType = Method->getThisType(Context); 1415 DestRecordType = DestType->getPointeeType(); 1416 1417 if (FromType->getAs<PointerType>()) { 1418 FromRecordType = FromType->getPointeeType(); 1419 PointerConversions = true; 1420 } else { 1421 FromRecordType = FromType; 1422 DestType = DestRecordType; 1423 } 1424 } else { 1425 // No conversion necessary. 1426 return false; 1427 } 1428 1429 if (DestType->isDependentType() || FromType->isDependentType()) 1430 return false; 1431 1432 // If the unqualified types are the same, no conversion is necessary. 1433 if (Context.hasSameUnqualifiedType(FromRecordType, DestRecordType)) 1434 return false; 1435 1436 SourceRange FromRange = From->getSourceRange(); 1437 SourceLocation FromLoc = FromRange.getBegin(); 1438 1439 // C++ [class.member.lookup]p8: 1440 // [...] Ambiguities can often be resolved by qualifying a name with its 1441 // class name. 1442 // 1443 // If the member was a qualified name and the qualified referred to a 1444 // specific base subobject type, we'll cast to that intermediate type 1445 // first and then to the object in which the member is declared. That allows 1446 // one to resolve ambiguities in, e.g., a diamond-shaped hierarchy such as: 1447 // 1448 // class Base { public: int x; }; 1449 // class Derived1 : public Base { }; 1450 // class Derived2 : public Base { }; 1451 // class VeryDerived : public Derived1, public Derived2 { void f(); }; 1452 // 1453 // void VeryDerived::f() { 1454 // x = 17; // error: ambiguous base subobjects 1455 // Derived1::x = 17; // okay, pick the Base subobject of Derived1 1456 // } 1457 if (Qualifier) { 1458 QualType QType = QualType(Qualifier->getAsType(), 0); 1459 assert(!QType.isNull() && "lookup done with dependent qualifier?"); 1460 assert(QType->isRecordType() && "lookup done with non-record type"); 1461 1462 QualType QRecordType = QualType(QType->getAs<RecordType>(), 0); 1463 1464 // In C++98, the qualifier type doesn't actually have to be a base 1465 // type of the object type, in which case we just ignore it. 1466 // Otherwise build the appropriate casts. 1467 if (IsDerivedFrom(FromRecordType, QRecordType)) { 1468 CXXBaseSpecifierArray BasePath; 1469 if (CheckDerivedToBaseConversion(FromRecordType, QRecordType, 1470 FromLoc, FromRange, &BasePath)) 1471 return true; 1472 1473 if (PointerConversions) 1474 QType = Context.getPointerType(QType); 1475 ImpCastExprToType(From, QType, CastExpr::CK_UncheckedDerivedToBase, 1476 /*isLvalue=*/!PointerConversions, BasePath); 1477 1478 FromType = QType; 1479 FromRecordType = QRecordType; 1480 1481 // If the qualifier type was the same as the destination type, 1482 // we're done. 1483 if (Context.hasSameUnqualifiedType(FromRecordType, DestRecordType)) 1484 return false; 1485 } 1486 } 1487 1488 bool IgnoreAccess = false; 1489 1490 // If we actually found the member through a using declaration, cast 1491 // down to the using declaration's type. 1492 // 1493 // Pointer equality is fine here because only one declaration of a 1494 // class ever has member declarations. 1495 if (FoundDecl->getDeclContext() != Member->getDeclContext()) { 1496 assert(isa<UsingShadowDecl>(FoundDecl)); 1497 QualType URecordType = Context.getTypeDeclType( 1498 cast<CXXRecordDecl>(FoundDecl->getDeclContext())); 1499 1500 // We only need to do this if the naming-class to declaring-class 1501 // conversion is non-trivial. 1502 if (!Context.hasSameUnqualifiedType(FromRecordType, URecordType)) { 1503 assert(IsDerivedFrom(FromRecordType, URecordType)); 1504 CXXBaseSpecifierArray BasePath; 1505 if (CheckDerivedToBaseConversion(FromRecordType, URecordType, 1506 FromLoc, FromRange, &BasePath)) 1507 return true; 1508 1509 QualType UType = URecordType; 1510 if (PointerConversions) 1511 UType = Context.getPointerType(UType); 1512 ImpCastExprToType(From, UType, CastExpr::CK_UncheckedDerivedToBase, 1513 /*isLvalue=*/!PointerConversions, BasePath); 1514 FromType = UType; 1515 FromRecordType = URecordType; 1516 } 1517 1518 // We don't do access control for the conversion from the 1519 // declaring class to the true declaring class. 1520 IgnoreAccess = true; 1521 } 1522 1523 CXXBaseSpecifierArray BasePath; 1524 if (CheckDerivedToBaseConversion(FromRecordType, DestRecordType, 1525 FromLoc, FromRange, &BasePath, 1526 IgnoreAccess)) 1527 return true; 1528 1529 ImpCastExprToType(From, DestType, CastExpr::CK_UncheckedDerivedToBase, 1530 /*isLvalue=*/!PointerConversions, BasePath); 1531 return false; 1532} 1533 1534/// \brief Build a MemberExpr AST node. 1535static MemberExpr *BuildMemberExpr(ASTContext &C, Expr *Base, bool isArrow, 1536 const CXXScopeSpec &SS, ValueDecl *Member, 1537 DeclAccessPair FoundDecl, 1538 SourceLocation Loc, QualType Ty, 1539 const TemplateArgumentListInfo *TemplateArgs = 0) { 1540 NestedNameSpecifier *Qualifier = 0; 1541 SourceRange QualifierRange; 1542 if (SS.isSet()) { 1543 Qualifier = (NestedNameSpecifier *) SS.getScopeRep(); 1544 QualifierRange = SS.getRange(); 1545 } 1546 1547 return MemberExpr::Create(C, Base, isArrow, Qualifier, QualifierRange, 1548 Member, FoundDecl, Loc, TemplateArgs, Ty); 1549} 1550 1551/// Builds an implicit member access expression. The current context 1552/// is known to be an instance method, and the given unqualified lookup 1553/// set is known to contain only instance members, at least one of which 1554/// is from an appropriate type. 1555Sema::OwningExprResult 1556Sema::BuildImplicitMemberExpr(const CXXScopeSpec &SS, 1557 LookupResult &R, 1558 const TemplateArgumentListInfo *TemplateArgs, 1559 bool IsKnownInstance) { 1560 assert(!R.empty() && !R.isAmbiguous()); 1561 1562 SourceLocation Loc = R.getNameLoc(); 1563 1564 // We may have found a field within an anonymous union or struct 1565 // (C++ [class.union]). 1566 // FIXME: This needs to happen post-isImplicitMemberReference? 1567 // FIXME: template-ids inside anonymous structs? 1568 if (FieldDecl *FD = R.getAsSingle<FieldDecl>()) 1569 if (cast<RecordDecl>(FD->getDeclContext())->isAnonymousStructOrUnion()) 1570 return BuildAnonymousStructUnionMemberReference(Loc, FD); 1571 1572 // If this is known to be an instance access, go ahead and build a 1573 // 'this' expression now. 1574 DeclContext *DC = getFunctionLevelDeclContext(); 1575 QualType ThisType = cast<CXXMethodDecl>(DC)->getThisType(Context); 1576 Expr *This = 0; // null signifies implicit access 1577 if (IsKnownInstance) { 1578 SourceLocation Loc = R.getNameLoc(); 1579 if (SS.getRange().isValid()) 1580 Loc = SS.getRange().getBegin(); 1581 This = new (Context) CXXThisExpr(Loc, ThisType, /*isImplicit=*/true); 1582 } 1583 1584 return BuildMemberReferenceExpr(ExprArg(*this, This), ThisType, 1585 /*OpLoc*/ SourceLocation(), 1586 /*IsArrow*/ true, 1587 SS, 1588 /*FirstQualifierInScope*/ 0, 1589 R, TemplateArgs); 1590} 1591 1592bool Sema::UseArgumentDependentLookup(const CXXScopeSpec &SS, 1593 const LookupResult &R, 1594 bool HasTrailingLParen) { 1595 // Only when used directly as the postfix-expression of a call. 1596 if (!HasTrailingLParen) 1597 return false; 1598 1599 // Never if a scope specifier was provided. 1600 if (SS.isSet()) 1601 return false; 1602 1603 // Only in C++ or ObjC++. 1604 if (!getLangOptions().CPlusPlus) 1605 return false; 1606 1607 // Turn off ADL when we find certain kinds of declarations during 1608 // normal lookup: 1609 for (LookupResult::iterator I = R.begin(), E = R.end(); I != E; ++I) { 1610 NamedDecl *D = *I; 1611 1612 // C++0x [basic.lookup.argdep]p3: 1613 // -- a declaration of a class member 1614 // Since using decls preserve this property, we check this on the 1615 // original decl. 1616 if (D->isCXXClassMember()) 1617 return false; 1618 1619 // C++0x [basic.lookup.argdep]p3: 1620 // -- a block-scope function declaration that is not a 1621 // using-declaration 1622 // NOTE: we also trigger this for function templates (in fact, we 1623 // don't check the decl type at all, since all other decl types 1624 // turn off ADL anyway). 1625 if (isa<UsingShadowDecl>(D)) 1626 D = cast<UsingShadowDecl>(D)->getTargetDecl(); 1627 else if (D->getDeclContext()->isFunctionOrMethod()) 1628 return false; 1629 1630 // C++0x [basic.lookup.argdep]p3: 1631 // -- a declaration that is neither a function or a function 1632 // template 1633 // And also for builtin functions. 1634 if (isa<FunctionDecl>(D)) { 1635 FunctionDecl *FDecl = cast<FunctionDecl>(D); 1636 1637 // But also builtin functions. 1638 if (FDecl->getBuiltinID() && FDecl->isImplicit()) 1639 return false; 1640 } else if (!isa<FunctionTemplateDecl>(D)) 1641 return false; 1642 } 1643 1644 return true; 1645} 1646 1647 1648/// Diagnoses obvious problems with the use of the given declaration 1649/// as an expression. This is only actually called for lookups that 1650/// were not overloaded, and it doesn't promise that the declaration 1651/// will in fact be used. 1652static bool CheckDeclInExpr(Sema &S, SourceLocation Loc, NamedDecl *D) { 1653 if (isa<TypedefDecl>(D)) { 1654 S.Diag(Loc, diag::err_unexpected_typedef) << D->getDeclName(); 1655 return true; 1656 } 1657 1658 if (isa<ObjCInterfaceDecl>(D)) { 1659 S.Diag(Loc, diag::err_unexpected_interface) << D->getDeclName(); 1660 return true; 1661 } 1662 1663 if (isa<NamespaceDecl>(D)) { 1664 S.Diag(Loc, diag::err_unexpected_namespace) << D->getDeclName(); 1665 return true; 1666 } 1667 1668 return false; 1669} 1670 1671Sema::OwningExprResult 1672Sema::BuildDeclarationNameExpr(const CXXScopeSpec &SS, 1673 LookupResult &R, 1674 bool NeedsADL) { 1675 // If this is a single, fully-resolved result and we don't need ADL, 1676 // just build an ordinary singleton decl ref. 1677 if (!NeedsADL && R.isSingleResult() && !R.getAsSingle<FunctionTemplateDecl>()) 1678 return BuildDeclarationNameExpr(SS, R.getNameLoc(), R.getFoundDecl()); 1679 1680 // We only need to check the declaration if there's exactly one 1681 // result, because in the overloaded case the results can only be 1682 // functions and function templates. 1683 if (R.isSingleResult() && 1684 CheckDeclInExpr(*this, R.getNameLoc(), R.getFoundDecl())) 1685 return ExprError(); 1686 1687 // Otherwise, just build an unresolved lookup expression. Suppress 1688 // any lookup-related diagnostics; we'll hash these out later, when 1689 // we've picked a target. 1690 R.suppressDiagnostics(); 1691 1692 bool Dependent 1693 = UnresolvedLookupExpr::ComputeDependence(R.begin(), R.end(), 0); 1694 UnresolvedLookupExpr *ULE 1695 = UnresolvedLookupExpr::Create(Context, Dependent, R.getNamingClass(), 1696 (NestedNameSpecifier*) SS.getScopeRep(), 1697 SS.getRange(), 1698 R.getLookupName(), R.getNameLoc(), 1699 NeedsADL, R.isOverloadedResult()); 1700 ULE->addDecls(R.begin(), R.end()); 1701 1702 return Owned(ULE); 1703} 1704 1705 1706/// \brief Complete semantic analysis for a reference to the given declaration. 1707Sema::OwningExprResult 1708Sema::BuildDeclarationNameExpr(const CXXScopeSpec &SS, 1709 SourceLocation Loc, NamedDecl *D) { 1710 assert(D && "Cannot refer to a NULL declaration"); 1711 assert(!isa<FunctionTemplateDecl>(D) && 1712 "Cannot refer unambiguously to a function template"); 1713 1714 if (CheckDeclInExpr(*this, Loc, D)) 1715 return ExprError(); 1716 1717 if (TemplateDecl *Template = dyn_cast<TemplateDecl>(D)) { 1718 // Specifically diagnose references to class templates that are missing 1719 // a template argument list. 1720 Diag(Loc, diag::err_template_decl_ref) 1721 << Template << SS.getRange(); 1722 Diag(Template->getLocation(), diag::note_template_decl_here); 1723 return ExprError(); 1724 } 1725 1726 // Make sure that we're referring to a value. 1727 ValueDecl *VD = dyn_cast<ValueDecl>(D); 1728 if (!VD) { 1729 Diag(Loc, diag::err_ref_non_value) 1730 << D << SS.getRange(); 1731 Diag(D->getLocation(), diag::note_declared_at); 1732 return ExprError(); 1733 } 1734 1735 // Check whether this declaration can be used. Note that we suppress 1736 // this check when we're going to perform argument-dependent lookup 1737 // on this function name, because this might not be the function 1738 // that overload resolution actually selects. 1739 if (DiagnoseUseOfDecl(VD, Loc)) 1740 return ExprError(); 1741 1742 // Only create DeclRefExpr's for valid Decl's. 1743 if (VD->isInvalidDecl()) 1744 return ExprError(); 1745 1746 // If the identifier reference is inside a block, and it refers to a value 1747 // that is outside the block, create a BlockDeclRefExpr instead of a 1748 // DeclRefExpr. This ensures the value is treated as a copy-in snapshot when 1749 // the block is formed. 1750 // 1751 // We do not do this for things like enum constants, global variables, etc, 1752 // as they do not get snapshotted. 1753 // 1754 if (getCurBlock() && 1755 ShouldSnapshotBlockValueReference(*this, getCurBlock(), VD)) { 1756 if (VD->getType().getTypePtr()->isVariablyModifiedType()) { 1757 Diag(Loc, diag::err_ref_vm_type); 1758 Diag(D->getLocation(), diag::note_declared_at); 1759 return ExprError(); 1760 } 1761 1762 if (VD->getType()->isArrayType()) { 1763 Diag(Loc, diag::err_ref_array_type); 1764 Diag(D->getLocation(), diag::note_declared_at); 1765 return ExprError(); 1766 } 1767 1768 MarkDeclarationReferenced(Loc, VD); 1769 QualType ExprTy = VD->getType().getNonReferenceType(); 1770 // The BlocksAttr indicates the variable is bound by-reference. 1771 if (VD->getAttr<BlocksAttr>()) 1772 return Owned(new (Context) BlockDeclRefExpr(VD, ExprTy, Loc, true)); 1773 // This is to record that a 'const' was actually synthesize and added. 1774 bool constAdded = !ExprTy.isConstQualified(); 1775 // Variable will be bound by-copy, make it const within the closure. 1776 1777 ExprTy.addConst(); 1778 return Owned(new (Context) BlockDeclRefExpr(VD, ExprTy, Loc, false, 1779 constAdded)); 1780 } 1781 // If this reference is not in a block or if the referenced variable is 1782 // within the block, create a normal DeclRefExpr. 1783 1784 return BuildDeclRefExpr(VD, VD->getType().getNonReferenceType(), Loc, &SS); 1785} 1786 1787Sema::OwningExprResult Sema::ActOnPredefinedExpr(SourceLocation Loc, 1788 tok::TokenKind Kind) { 1789 PredefinedExpr::IdentType IT; 1790 1791 switch (Kind) { 1792 default: assert(0 && "Unknown simple primary expr!"); 1793 case tok::kw___func__: IT = PredefinedExpr::Func; break; // [C99 6.4.2.2] 1794 case tok::kw___FUNCTION__: IT = PredefinedExpr::Function; break; 1795 case tok::kw___PRETTY_FUNCTION__: IT = PredefinedExpr::PrettyFunction; break; 1796 } 1797 1798 // Pre-defined identifiers are of type char[x], where x is the length of the 1799 // string. 1800 1801 Decl *currentDecl = getCurFunctionOrMethodDecl(); 1802 if (!currentDecl) { 1803 Diag(Loc, diag::ext_predef_outside_function); 1804 currentDecl = Context.getTranslationUnitDecl(); 1805 } 1806 1807 QualType ResTy; 1808 if (cast<DeclContext>(currentDecl)->isDependentContext()) { 1809 ResTy = Context.DependentTy; 1810 } else { 1811 unsigned Length = PredefinedExpr::ComputeName(IT, currentDecl).length(); 1812 1813 llvm::APInt LengthI(32, Length + 1); 1814 ResTy = Context.CharTy.withConst(); 1815 ResTy = Context.getConstantArrayType(ResTy, LengthI, ArrayType::Normal, 0); 1816 } 1817 return Owned(new (Context) PredefinedExpr(Loc, ResTy, IT)); 1818} 1819 1820Sema::OwningExprResult Sema::ActOnCharacterConstant(const Token &Tok) { 1821 llvm::SmallString<16> CharBuffer; 1822 bool Invalid = false; 1823 llvm::StringRef ThisTok = PP.getSpelling(Tok, CharBuffer, &Invalid); 1824 if (Invalid) 1825 return ExprError(); 1826 1827 CharLiteralParser Literal(ThisTok.begin(), ThisTok.end(), Tok.getLocation(), 1828 PP); 1829 if (Literal.hadError()) 1830 return ExprError(); 1831 1832 QualType Ty; 1833 if (!getLangOptions().CPlusPlus) 1834 Ty = Context.IntTy; // 'x' and L'x' -> int in C. 1835 else if (Literal.isWide()) 1836 Ty = Context.WCharTy; // L'x' -> wchar_t in C++. 1837 else if (Literal.isMultiChar()) 1838 Ty = Context.IntTy; // 'wxyz' -> int in C++. 1839 else 1840 Ty = Context.CharTy; // 'x' -> char in C++ 1841 1842 return Owned(new (Context) CharacterLiteral(Literal.getValue(), 1843 Literal.isWide(), 1844 Ty, Tok.getLocation())); 1845} 1846 1847Action::OwningExprResult Sema::ActOnNumericConstant(const Token &Tok) { 1848 // Fast path for a single digit (which is quite common). A single digit 1849 // cannot have a trigraph, escaped newline, radix prefix, or type suffix. 1850 if (Tok.getLength() == 1) { 1851 const char Val = PP.getSpellingOfSingleCharacterNumericConstant(Tok); 1852 unsigned IntSize = Context.Target.getIntWidth(); 1853 return Owned(new (Context) IntegerLiteral(llvm::APInt(IntSize, Val-'0'), 1854 Context.IntTy, Tok.getLocation())); 1855 } 1856 1857 llvm::SmallString<512> IntegerBuffer; 1858 // Add padding so that NumericLiteralParser can overread by one character. 1859 IntegerBuffer.resize(Tok.getLength()+1); 1860 const char *ThisTokBegin = &IntegerBuffer[0]; 1861 1862 // Get the spelling of the token, which eliminates trigraphs, etc. 1863 bool Invalid = false; 1864 unsigned ActualLength = PP.getSpelling(Tok, ThisTokBegin, &Invalid); 1865 if (Invalid) 1866 return ExprError(); 1867 1868 NumericLiteralParser Literal(ThisTokBegin, ThisTokBegin+ActualLength, 1869 Tok.getLocation(), PP); 1870 if (Literal.hadError) 1871 return ExprError(); 1872 1873 Expr *Res; 1874 1875 if (Literal.isFloatingLiteral()) { 1876 QualType Ty; 1877 if (Literal.isFloat) 1878 Ty = Context.FloatTy; 1879 else if (!Literal.isLong) 1880 Ty = Context.DoubleTy; 1881 else 1882 Ty = Context.LongDoubleTy; 1883 1884 const llvm::fltSemantics &Format = Context.getFloatTypeSemantics(Ty); 1885 1886 using llvm::APFloat; 1887 APFloat Val(Format); 1888 1889 APFloat::opStatus result = Literal.GetFloatValue(Val); 1890 1891 // Overflow is always an error, but underflow is only an error if 1892 // we underflowed to zero (APFloat reports denormals as underflow). 1893 if ((result & APFloat::opOverflow) || 1894 ((result & APFloat::opUnderflow) && Val.isZero())) { 1895 unsigned diagnostic; 1896 llvm::SmallString<20> buffer; 1897 if (result & APFloat::opOverflow) { 1898 diagnostic = diag::warn_float_overflow; 1899 APFloat::getLargest(Format).toString(buffer); 1900 } else { 1901 diagnostic = diag::warn_float_underflow; 1902 APFloat::getSmallest(Format).toString(buffer); 1903 } 1904 1905 Diag(Tok.getLocation(), diagnostic) 1906 << Ty 1907 << llvm::StringRef(buffer.data(), buffer.size()); 1908 } 1909 1910 bool isExact = (result == APFloat::opOK); 1911 Res = new (Context) FloatingLiteral(Val, isExact, Ty, Tok.getLocation()); 1912 1913 } else if (!Literal.isIntegerLiteral()) { 1914 return ExprError(); 1915 } else { 1916 QualType Ty; 1917 1918 // long long is a C99 feature. 1919 if (!getLangOptions().C99 && !getLangOptions().CPlusPlus0x && 1920 Literal.isLongLong) 1921 Diag(Tok.getLocation(), diag::ext_longlong); 1922 1923 // Get the value in the widest-possible width. 1924 llvm::APInt ResultVal(Context.Target.getIntMaxTWidth(), 0); 1925 1926 if (Literal.GetIntegerValue(ResultVal)) { 1927 // If this value didn't fit into uintmax_t, warn and force to ull. 1928 Diag(Tok.getLocation(), diag::warn_integer_too_large); 1929 Ty = Context.UnsignedLongLongTy; 1930 assert(Context.getTypeSize(Ty) == ResultVal.getBitWidth() && 1931 "long long is not intmax_t?"); 1932 } else { 1933 // If this value fits into a ULL, try to figure out what else it fits into 1934 // according to the rules of C99 6.4.4.1p5. 1935 1936 // Octal, Hexadecimal, and integers with a U suffix are allowed to 1937 // be an unsigned int. 1938 bool AllowUnsigned = Literal.isUnsigned || Literal.getRadix() != 10; 1939 1940 // Check from smallest to largest, picking the smallest type we can. 1941 unsigned Width = 0; 1942 if (!Literal.isLong && !Literal.isLongLong) { 1943 // Are int/unsigned possibilities? 1944 unsigned IntSize = Context.Target.getIntWidth(); 1945 1946 // Does it fit in a unsigned int? 1947 if (ResultVal.isIntN(IntSize)) { 1948 // Does it fit in a signed int? 1949 if (!Literal.isUnsigned && ResultVal[IntSize-1] == 0) 1950 Ty = Context.IntTy; 1951 else if (AllowUnsigned) 1952 Ty = Context.UnsignedIntTy; 1953 Width = IntSize; 1954 } 1955 } 1956 1957 // Are long/unsigned long possibilities? 1958 if (Ty.isNull() && !Literal.isLongLong) { 1959 unsigned LongSize = Context.Target.getLongWidth(); 1960 1961 // Does it fit in a unsigned long? 1962 if (ResultVal.isIntN(LongSize)) { 1963 // Does it fit in a signed long? 1964 if (!Literal.isUnsigned && ResultVal[LongSize-1] == 0) 1965 Ty = Context.LongTy; 1966 else if (AllowUnsigned) 1967 Ty = Context.UnsignedLongTy; 1968 Width = LongSize; 1969 } 1970 } 1971 1972 // Finally, check long long if needed. 1973 if (Ty.isNull()) { 1974 unsigned LongLongSize = Context.Target.getLongLongWidth(); 1975 1976 // Does it fit in a unsigned long long? 1977 if (ResultVal.isIntN(LongLongSize)) { 1978 // Does it fit in a signed long long? 1979 if (!Literal.isUnsigned && ResultVal[LongLongSize-1] == 0) 1980 Ty = Context.LongLongTy; 1981 else if (AllowUnsigned) 1982 Ty = Context.UnsignedLongLongTy; 1983 Width = LongLongSize; 1984 } 1985 } 1986 1987 // If we still couldn't decide a type, we probably have something that 1988 // does not fit in a signed long long, but has no U suffix. 1989 if (Ty.isNull()) { 1990 Diag(Tok.getLocation(), diag::warn_integer_too_large_for_signed); 1991 Ty = Context.UnsignedLongLongTy; 1992 Width = Context.Target.getLongLongWidth(); 1993 } 1994 1995 if (ResultVal.getBitWidth() != Width) 1996 ResultVal.trunc(Width); 1997 } 1998 Res = new (Context) IntegerLiteral(ResultVal, Ty, Tok.getLocation()); 1999 } 2000 2001 // If this is an imaginary literal, create the ImaginaryLiteral wrapper. 2002 if (Literal.isImaginary) 2003 Res = new (Context) ImaginaryLiteral(Res, 2004 Context.getComplexType(Res->getType())); 2005 2006 return Owned(Res); 2007} 2008 2009Action::OwningExprResult Sema::ActOnParenExpr(SourceLocation L, 2010 SourceLocation R, ExprArg Val) { 2011 Expr *E = Val.takeAs<Expr>(); 2012 assert((E != 0) && "ActOnParenExpr() missing expr"); 2013 return Owned(new (Context) ParenExpr(L, R, E)); 2014} 2015 2016/// The UsualUnaryConversions() function is *not* called by this routine. 2017/// See C99 6.3.2.1p[2-4] for more details. 2018bool Sema::CheckSizeOfAlignOfOperand(QualType exprType, 2019 SourceLocation OpLoc, 2020 const SourceRange &ExprRange, 2021 bool isSizeof) { 2022 if (exprType->isDependentType()) 2023 return false; 2024 2025 // C++ [expr.sizeof]p2: "When applied to a reference or a reference type, 2026 // the result is the size of the referenced type." 2027 // C++ [expr.alignof]p3: "When alignof is applied to a reference type, the 2028 // result shall be the alignment of the referenced type." 2029 if (const ReferenceType *Ref = exprType->getAs<ReferenceType>()) 2030 exprType = Ref->getPointeeType(); 2031 2032 // C99 6.5.3.4p1: 2033 if (exprType->isFunctionType()) { 2034 // alignof(function) is allowed as an extension. 2035 if (isSizeof) 2036 Diag(OpLoc, diag::ext_sizeof_function_type) << ExprRange; 2037 return false; 2038 } 2039 2040 // Allow sizeof(void)/alignof(void) as an extension. 2041 if (exprType->isVoidType()) { 2042 Diag(OpLoc, diag::ext_sizeof_void_type) 2043 << (isSizeof ? "sizeof" : "__alignof") << ExprRange; 2044 return false; 2045 } 2046 2047 if (RequireCompleteType(OpLoc, exprType, 2048 PDiag(diag::err_sizeof_alignof_incomplete_type) 2049 << int(!isSizeof) << ExprRange)) 2050 return true; 2051 2052 // Reject sizeof(interface) and sizeof(interface<proto>) in 64-bit mode. 2053 if (LangOpts.ObjCNonFragileABI && exprType->isObjCObjectType()) { 2054 Diag(OpLoc, diag::err_sizeof_nonfragile_interface) 2055 << exprType << isSizeof << ExprRange; 2056 return true; 2057 } 2058 2059 return false; 2060} 2061 2062bool Sema::CheckAlignOfExpr(Expr *E, SourceLocation OpLoc, 2063 const SourceRange &ExprRange) { 2064 E = E->IgnoreParens(); 2065 2066 // alignof decl is always ok. 2067 if (isa<DeclRefExpr>(E)) 2068 return false; 2069 2070 // Cannot know anything else if the expression is dependent. 2071 if (E->isTypeDependent()) 2072 return false; 2073 2074 if (E->getBitField()) { 2075 Diag(OpLoc, diag::err_sizeof_alignof_bitfield) << 1 << ExprRange; 2076 return true; 2077 } 2078 2079 // Alignment of a field access is always okay, so long as it isn't a 2080 // bit-field. 2081 if (MemberExpr *ME = dyn_cast<MemberExpr>(E)) 2082 if (isa<FieldDecl>(ME->getMemberDecl())) 2083 return false; 2084 2085 return CheckSizeOfAlignOfOperand(E->getType(), OpLoc, ExprRange, false); 2086} 2087 2088/// \brief Build a sizeof or alignof expression given a type operand. 2089Action::OwningExprResult 2090Sema::CreateSizeOfAlignOfExpr(TypeSourceInfo *TInfo, 2091 SourceLocation OpLoc, 2092 bool isSizeOf, SourceRange R) { 2093 if (!TInfo) 2094 return ExprError(); 2095 2096 QualType T = TInfo->getType(); 2097 2098 if (!T->isDependentType() && 2099 CheckSizeOfAlignOfOperand(T, OpLoc, R, isSizeOf)) 2100 return ExprError(); 2101 2102 // C99 6.5.3.4p4: the type (an unsigned integer type) is size_t. 2103 return Owned(new (Context) SizeOfAlignOfExpr(isSizeOf, TInfo, 2104 Context.getSizeType(), OpLoc, 2105 R.getEnd())); 2106} 2107 2108/// \brief Build a sizeof or alignof expression given an expression 2109/// operand. 2110Action::OwningExprResult 2111Sema::CreateSizeOfAlignOfExpr(Expr *E, SourceLocation OpLoc, 2112 bool isSizeOf, SourceRange R) { 2113 // Verify that the operand is valid. 2114 bool isInvalid = false; 2115 if (E->isTypeDependent()) { 2116 // Delay type-checking for type-dependent expressions. 2117 } else if (!isSizeOf) { 2118 isInvalid = CheckAlignOfExpr(E, OpLoc, R); 2119 } else if (E->getBitField()) { // C99 6.5.3.4p1. 2120 Diag(OpLoc, diag::err_sizeof_alignof_bitfield) << 0; 2121 isInvalid = true; 2122 } else { 2123 isInvalid = CheckSizeOfAlignOfOperand(E->getType(), OpLoc, R, true); 2124 } 2125 2126 if (isInvalid) 2127 return ExprError(); 2128 2129 // C99 6.5.3.4p4: the type (an unsigned integer type) is size_t. 2130 return Owned(new (Context) SizeOfAlignOfExpr(isSizeOf, E, 2131 Context.getSizeType(), OpLoc, 2132 R.getEnd())); 2133} 2134 2135/// ActOnSizeOfAlignOfExpr - Handle @c sizeof(type) and @c sizeof @c expr and 2136/// the same for @c alignof and @c __alignof 2137/// Note that the ArgRange is invalid if isType is false. 2138Action::OwningExprResult 2139Sema::ActOnSizeOfAlignOfExpr(SourceLocation OpLoc, bool isSizeof, bool isType, 2140 void *TyOrEx, const SourceRange &ArgRange) { 2141 // If error parsing type, ignore. 2142 if (TyOrEx == 0) return ExprError(); 2143 2144 if (isType) { 2145 TypeSourceInfo *TInfo; 2146 (void) GetTypeFromParser(TyOrEx, &TInfo); 2147 return CreateSizeOfAlignOfExpr(TInfo, OpLoc, isSizeof, ArgRange); 2148 } 2149 2150 Expr *ArgEx = (Expr *)TyOrEx; 2151 Action::OwningExprResult Result 2152 = CreateSizeOfAlignOfExpr(ArgEx, OpLoc, isSizeof, ArgEx->getSourceRange()); 2153 2154 if (Result.isInvalid()) 2155 DeleteExpr(ArgEx); 2156 2157 return move(Result); 2158} 2159 2160QualType Sema::CheckRealImagOperand(Expr *&V, SourceLocation Loc, bool isReal) { 2161 if (V->isTypeDependent()) 2162 return Context.DependentTy; 2163 2164 // These operators return the element type of a complex type. 2165 if (const ComplexType *CT = V->getType()->getAs<ComplexType>()) 2166 return CT->getElementType(); 2167 2168 // Otherwise they pass through real integer and floating point types here. 2169 if (V->getType()->isArithmeticType()) 2170 return V->getType(); 2171 2172 // Reject anything else. 2173 Diag(Loc, diag::err_realimag_invalid_type) << V->getType() 2174 << (isReal ? "__real" : "__imag"); 2175 return QualType(); 2176} 2177 2178 2179 2180Action::OwningExprResult 2181Sema::ActOnPostfixUnaryOp(Scope *S, SourceLocation OpLoc, 2182 tok::TokenKind Kind, ExprArg Input) { 2183 UnaryOperator::Opcode Opc; 2184 switch (Kind) { 2185 default: assert(0 && "Unknown unary op!"); 2186 case tok::plusplus: Opc = UnaryOperator::PostInc; break; 2187 case tok::minusminus: Opc = UnaryOperator::PostDec; break; 2188 } 2189 2190 return BuildUnaryOp(S, OpLoc, Opc, move(Input)); 2191} 2192 2193Action::OwningExprResult 2194Sema::ActOnArraySubscriptExpr(Scope *S, ExprArg Base, SourceLocation LLoc, 2195 ExprArg Idx, SourceLocation RLoc) { 2196 // Since this might be a postfix expression, get rid of ParenListExprs. 2197 Base = MaybeConvertParenListExprToParenExpr(S, move(Base)); 2198 2199 Expr *LHSExp = static_cast<Expr*>(Base.get()), 2200 *RHSExp = static_cast<Expr*>(Idx.get()); 2201 2202 if (getLangOptions().CPlusPlus && 2203 (LHSExp->isTypeDependent() || RHSExp->isTypeDependent())) { 2204 Base.release(); 2205 Idx.release(); 2206 return Owned(new (Context) ArraySubscriptExpr(LHSExp, RHSExp, 2207 Context.DependentTy, RLoc)); 2208 } 2209 2210 if (getLangOptions().CPlusPlus && 2211 (LHSExp->getType()->isRecordType() || 2212 LHSExp->getType()->isEnumeralType() || 2213 RHSExp->getType()->isRecordType() || 2214 RHSExp->getType()->isEnumeralType())) { 2215 return CreateOverloadedArraySubscriptExpr(LLoc, RLoc, move(Base),move(Idx)); 2216 } 2217 2218 return CreateBuiltinArraySubscriptExpr(move(Base), LLoc, move(Idx), RLoc); 2219} 2220 2221 2222Action::OwningExprResult 2223Sema::CreateBuiltinArraySubscriptExpr(ExprArg Base, SourceLocation LLoc, 2224 ExprArg Idx, SourceLocation RLoc) { 2225 Expr *LHSExp = static_cast<Expr*>(Base.get()); 2226 Expr *RHSExp = static_cast<Expr*>(Idx.get()); 2227 2228 // Perform default conversions. 2229 if (!LHSExp->getType()->getAs<VectorType>()) 2230 DefaultFunctionArrayLvalueConversion(LHSExp); 2231 DefaultFunctionArrayLvalueConversion(RHSExp); 2232 2233 QualType LHSTy = LHSExp->getType(), RHSTy = RHSExp->getType(); 2234 2235 // C99 6.5.2.1p2: the expression e1[e2] is by definition precisely equivalent 2236 // to the expression *((e1)+(e2)). This means the array "Base" may actually be 2237 // in the subscript position. As a result, we need to derive the array base 2238 // and index from the expression types. 2239 Expr *BaseExpr, *IndexExpr; 2240 QualType ResultType; 2241 if (LHSTy->isDependentType() || RHSTy->isDependentType()) { 2242 BaseExpr = LHSExp; 2243 IndexExpr = RHSExp; 2244 ResultType = Context.DependentTy; 2245 } else if (const PointerType *PTy = LHSTy->getAs<PointerType>()) { 2246 BaseExpr = LHSExp; 2247 IndexExpr = RHSExp; 2248 ResultType = PTy->getPointeeType(); 2249 } else if (const PointerType *PTy = RHSTy->getAs<PointerType>()) { 2250 // Handle the uncommon case of "123[Ptr]". 2251 BaseExpr = RHSExp; 2252 IndexExpr = LHSExp; 2253 ResultType = PTy->getPointeeType(); 2254 } else if (const ObjCObjectPointerType *PTy = 2255 LHSTy->getAs<ObjCObjectPointerType>()) { 2256 BaseExpr = LHSExp; 2257 IndexExpr = RHSExp; 2258 ResultType = PTy->getPointeeType(); 2259 } else if (const ObjCObjectPointerType *PTy = 2260 RHSTy->getAs<ObjCObjectPointerType>()) { 2261 // Handle the uncommon case of "123[Ptr]". 2262 BaseExpr = RHSExp; 2263 IndexExpr = LHSExp; 2264 ResultType = PTy->getPointeeType(); 2265 } else if (const VectorType *VTy = LHSTy->getAs<VectorType>()) { 2266 BaseExpr = LHSExp; // vectors: V[123] 2267 IndexExpr = RHSExp; 2268 2269 // FIXME: need to deal with const... 2270 ResultType = VTy->getElementType(); 2271 } else if (LHSTy->isArrayType()) { 2272 // If we see an array that wasn't promoted by 2273 // DefaultFunctionArrayLvalueConversion, it must be an array that 2274 // wasn't promoted because of the C90 rule that doesn't 2275 // allow promoting non-lvalue arrays. Warn, then 2276 // force the promotion here. 2277 Diag(LHSExp->getLocStart(), diag::ext_subscript_non_lvalue) << 2278 LHSExp->getSourceRange(); 2279 ImpCastExprToType(LHSExp, Context.getArrayDecayedType(LHSTy), 2280 CastExpr::CK_ArrayToPointerDecay); 2281 LHSTy = LHSExp->getType(); 2282 2283 BaseExpr = LHSExp; 2284 IndexExpr = RHSExp; 2285 ResultType = LHSTy->getAs<PointerType>()->getPointeeType(); 2286 } else if (RHSTy->isArrayType()) { 2287 // Same as previous, except for 123[f().a] case 2288 Diag(RHSExp->getLocStart(), diag::ext_subscript_non_lvalue) << 2289 RHSExp->getSourceRange(); 2290 ImpCastExprToType(RHSExp, Context.getArrayDecayedType(RHSTy), 2291 CastExpr::CK_ArrayToPointerDecay); 2292 RHSTy = RHSExp->getType(); 2293 2294 BaseExpr = RHSExp; 2295 IndexExpr = LHSExp; 2296 ResultType = RHSTy->getAs<PointerType>()->getPointeeType(); 2297 } else { 2298 return ExprError(Diag(LLoc, diag::err_typecheck_subscript_value) 2299 << LHSExp->getSourceRange() << RHSExp->getSourceRange()); 2300 } 2301 // C99 6.5.2.1p1 2302 if (!(IndexExpr->getType()->isIntegerType() && 2303 IndexExpr->getType()->isScalarType()) && !IndexExpr->isTypeDependent()) 2304 return ExprError(Diag(LLoc, diag::err_typecheck_subscript_not_integer) 2305 << IndexExpr->getSourceRange()); 2306 2307 if ((IndexExpr->getType()->isSpecificBuiltinType(BuiltinType::Char_S) || 2308 IndexExpr->getType()->isSpecificBuiltinType(BuiltinType::Char_U)) 2309 && !IndexExpr->isTypeDependent()) 2310 Diag(LLoc, diag::warn_subscript_is_char) << IndexExpr->getSourceRange(); 2311 2312 // C99 6.5.2.1p1: "shall have type "pointer to *object* type". Similarly, 2313 // C++ [expr.sub]p1: The type "T" shall be a completely-defined object 2314 // type. Note that Functions are not objects, and that (in C99 parlance) 2315 // incomplete types are not object types. 2316 if (ResultType->isFunctionType()) { 2317 Diag(BaseExpr->getLocStart(), diag::err_subscript_function_type) 2318 << ResultType << BaseExpr->getSourceRange(); 2319 return ExprError(); 2320 } 2321 2322 if (!ResultType->isDependentType() && 2323 RequireCompleteType(LLoc, ResultType, 2324 PDiag(diag::err_subscript_incomplete_type) 2325 << BaseExpr->getSourceRange())) 2326 return ExprError(); 2327 2328 // Diagnose bad cases where we step over interface counts. 2329 if (ResultType->isObjCObjectType() && LangOpts.ObjCNonFragileABI) { 2330 Diag(LLoc, diag::err_subscript_nonfragile_interface) 2331 << ResultType << BaseExpr->getSourceRange(); 2332 return ExprError(); 2333 } 2334 2335 Base.release(); 2336 Idx.release(); 2337 return Owned(new (Context) ArraySubscriptExpr(LHSExp, RHSExp, 2338 ResultType, RLoc)); 2339} 2340 2341QualType Sema:: 2342CheckExtVectorComponent(QualType baseType, SourceLocation OpLoc, 2343 const IdentifierInfo *CompName, 2344 SourceLocation CompLoc) { 2345 // FIXME: Share logic with ExtVectorElementExpr::containsDuplicateElements, 2346 // see FIXME there. 2347 // 2348 // FIXME: This logic can be greatly simplified by splitting it along 2349 // halving/not halving and reworking the component checking. 2350 const ExtVectorType *vecType = baseType->getAs<ExtVectorType>(); 2351 2352 // The vector accessor can't exceed the number of elements. 2353 const char *compStr = CompName->getNameStart(); 2354 2355 // This flag determines whether or not the component is one of the four 2356 // special names that indicate a subset of exactly half the elements are 2357 // to be selected. 2358 bool HalvingSwizzle = false; 2359 2360 // This flag determines whether or not CompName has an 's' char prefix, 2361 // indicating that it is a string of hex values to be used as vector indices. 2362 bool HexSwizzle = *compStr == 's' || *compStr == 'S'; 2363 2364 // Check that we've found one of the special components, or that the component 2365 // names must come from the same set. 2366 if (!strcmp(compStr, "hi") || !strcmp(compStr, "lo") || 2367 !strcmp(compStr, "even") || !strcmp(compStr, "odd")) { 2368 HalvingSwizzle = true; 2369 } else if (vecType->getPointAccessorIdx(*compStr) != -1) { 2370 do 2371 compStr++; 2372 while (*compStr && vecType->getPointAccessorIdx(*compStr) != -1); 2373 } else if (HexSwizzle || vecType->getNumericAccessorIdx(*compStr) != -1) { 2374 do 2375 compStr++; 2376 while (*compStr && vecType->getNumericAccessorIdx(*compStr) != -1); 2377 } 2378 2379 if (!HalvingSwizzle && *compStr) { 2380 // We didn't get to the end of the string. This means the component names 2381 // didn't come from the same set *or* we encountered an illegal name. 2382 Diag(OpLoc, diag::err_ext_vector_component_name_illegal) 2383 << std::string(compStr,compStr+1) << SourceRange(CompLoc); 2384 return QualType(); 2385 } 2386 2387 // Ensure no component accessor exceeds the width of the vector type it 2388 // operates on. 2389 if (!HalvingSwizzle) { 2390 compStr = CompName->getNameStart(); 2391 2392 if (HexSwizzle) 2393 compStr++; 2394 2395 while (*compStr) { 2396 if (!vecType->isAccessorWithinNumElements(*compStr++)) { 2397 Diag(OpLoc, diag::err_ext_vector_component_exceeds_length) 2398 << baseType << SourceRange(CompLoc); 2399 return QualType(); 2400 } 2401 } 2402 } 2403 2404 // The component accessor looks fine - now we need to compute the actual type. 2405 // The vector type is implied by the component accessor. For example, 2406 // vec4.b is a float, vec4.xy is a vec2, vec4.rgb is a vec3, etc. 2407 // vec4.s0 is a float, vec4.s23 is a vec3, etc. 2408 // vec4.hi, vec4.lo, vec4.e, and vec4.o all return vec2. 2409 unsigned CompSize = HalvingSwizzle ? (vecType->getNumElements() + 1) / 2 2410 : CompName->getLength(); 2411 if (HexSwizzle) 2412 CompSize--; 2413 2414 if (CompSize == 1) 2415 return vecType->getElementType(); 2416 2417 QualType VT = Context.getExtVectorType(vecType->getElementType(), CompSize); 2418 // Now look up the TypeDefDecl from the vector type. Without this, 2419 // diagostics look bad. We want extended vector types to appear built-in. 2420 for (unsigned i = 0, E = ExtVectorDecls.size(); i != E; ++i) { 2421 if (ExtVectorDecls[i]->getUnderlyingType() == VT) 2422 return Context.getTypedefType(ExtVectorDecls[i]); 2423 } 2424 return VT; // should never get here (a typedef type should always be found). 2425} 2426 2427static Decl *FindGetterNameDeclFromProtocolList(const ObjCProtocolDecl*PDecl, 2428 IdentifierInfo *Member, 2429 const Selector &Sel, 2430 ASTContext &Context) { 2431 2432 if (ObjCPropertyDecl *PD = PDecl->FindPropertyDeclaration(Member)) 2433 return PD; 2434 if (ObjCMethodDecl *OMD = PDecl->getInstanceMethod(Sel)) 2435 return OMD; 2436 2437 for (ObjCProtocolDecl::protocol_iterator I = PDecl->protocol_begin(), 2438 E = PDecl->protocol_end(); I != E; ++I) { 2439 if (Decl *D = FindGetterNameDeclFromProtocolList(*I, Member, Sel, 2440 Context)) 2441 return D; 2442 } 2443 return 0; 2444} 2445 2446static Decl *FindGetterNameDecl(const ObjCObjectPointerType *QIdTy, 2447 IdentifierInfo *Member, 2448 const Selector &Sel, 2449 ASTContext &Context) { 2450 // Check protocols on qualified interfaces. 2451 Decl *GDecl = 0; 2452 for (ObjCObjectPointerType::qual_iterator I = QIdTy->qual_begin(), 2453 E = QIdTy->qual_end(); I != E; ++I) { 2454 if (ObjCPropertyDecl *PD = (*I)->FindPropertyDeclaration(Member)) { 2455 GDecl = PD; 2456 break; 2457 } 2458 // Also must look for a getter name which uses property syntax. 2459 if (ObjCMethodDecl *OMD = (*I)->getInstanceMethod(Sel)) { 2460 GDecl = OMD; 2461 break; 2462 } 2463 } 2464 if (!GDecl) { 2465 for (ObjCObjectPointerType::qual_iterator I = QIdTy->qual_begin(), 2466 E = QIdTy->qual_end(); I != E; ++I) { 2467 // Search in the protocol-qualifier list of current protocol. 2468 GDecl = FindGetterNameDeclFromProtocolList(*I, Member, Sel, Context); 2469 if (GDecl) 2470 return GDecl; 2471 } 2472 } 2473 return GDecl; 2474} 2475 2476Sema::OwningExprResult 2477Sema::ActOnDependentMemberExpr(ExprArg Base, QualType BaseType, 2478 bool IsArrow, SourceLocation OpLoc, 2479 const CXXScopeSpec &SS, 2480 NamedDecl *FirstQualifierInScope, 2481 DeclarationName Name, SourceLocation NameLoc, 2482 const TemplateArgumentListInfo *TemplateArgs) { 2483 Expr *BaseExpr = Base.takeAs<Expr>(); 2484 2485 // Even in dependent contexts, try to diagnose base expressions with 2486 // obviously wrong types, e.g.: 2487 // 2488 // T* t; 2489 // t.f; 2490 // 2491 // In Obj-C++, however, the above expression is valid, since it could be 2492 // accessing the 'f' property if T is an Obj-C interface. The extra check 2493 // allows this, while still reporting an error if T is a struct pointer. 2494 if (!IsArrow) { 2495 const PointerType *PT = BaseType->getAs<PointerType>(); 2496 if (PT && (!getLangOptions().ObjC1 || 2497 PT->getPointeeType()->isRecordType())) { 2498 assert(BaseExpr && "cannot happen with implicit member accesses"); 2499 Diag(NameLoc, diag::err_typecheck_member_reference_struct_union) 2500 << BaseType << BaseExpr->getSourceRange(); 2501 return ExprError(); 2502 } 2503 } 2504 2505 assert(BaseType->isDependentType() || Name.isDependentName() || 2506 isDependentScopeSpecifier(SS)); 2507 2508 // Get the type being accessed in BaseType. If this is an arrow, the BaseExpr 2509 // must have pointer type, and the accessed type is the pointee. 2510 return Owned(CXXDependentScopeMemberExpr::Create(Context, BaseExpr, BaseType, 2511 IsArrow, OpLoc, 2512 static_cast<NestedNameSpecifier*>(SS.getScopeRep()), 2513 SS.getRange(), 2514 FirstQualifierInScope, 2515 Name, NameLoc, 2516 TemplateArgs)); 2517} 2518 2519/// We know that the given qualified member reference points only to 2520/// declarations which do not belong to the static type of the base 2521/// expression. Diagnose the problem. 2522static void DiagnoseQualifiedMemberReference(Sema &SemaRef, 2523 Expr *BaseExpr, 2524 QualType BaseType, 2525 const CXXScopeSpec &SS, 2526 const LookupResult &R) { 2527 // If this is an implicit member access, use a different set of 2528 // diagnostics. 2529 if (!BaseExpr) 2530 return DiagnoseInstanceReference(SemaRef, SS, R); 2531 2532 SemaRef.Diag(R.getNameLoc(), diag::err_qualified_member_of_unrelated) 2533 << SS.getRange() << R.getRepresentativeDecl() << BaseType; 2534} 2535 2536// Check whether the declarations we found through a nested-name 2537// specifier in a member expression are actually members of the base 2538// type. The restriction here is: 2539// 2540// C++ [expr.ref]p2: 2541// ... In these cases, the id-expression shall name a 2542// member of the class or of one of its base classes. 2543// 2544// So it's perfectly legitimate for the nested-name specifier to name 2545// an unrelated class, and for us to find an overload set including 2546// decls from classes which are not superclasses, as long as the decl 2547// we actually pick through overload resolution is from a superclass. 2548bool Sema::CheckQualifiedMemberReference(Expr *BaseExpr, 2549 QualType BaseType, 2550 const CXXScopeSpec &SS, 2551 const LookupResult &R) { 2552 const RecordType *BaseRT = BaseType->getAs<RecordType>(); 2553 if (!BaseRT) { 2554 // We can't check this yet because the base type is still 2555 // dependent. 2556 assert(BaseType->isDependentType()); 2557 return false; 2558 } 2559 CXXRecordDecl *BaseRecord = cast<CXXRecordDecl>(BaseRT->getDecl()); 2560 2561 for (LookupResult::iterator I = R.begin(), E = R.end(); I != E; ++I) { 2562 // If this is an implicit member reference and we find a 2563 // non-instance member, it's not an error. 2564 if (!BaseExpr && !(*I)->isCXXInstanceMember()) 2565 return false; 2566 2567 // Note that we use the DC of the decl, not the underlying decl. 2568 CXXRecordDecl *RecordD = cast<CXXRecordDecl>((*I)->getDeclContext()); 2569 while (RecordD->isAnonymousStructOrUnion()) 2570 RecordD = cast<CXXRecordDecl>(RecordD->getParent()); 2571 2572 llvm::SmallPtrSet<CXXRecordDecl*,4> MemberRecord; 2573 MemberRecord.insert(RecordD->getCanonicalDecl()); 2574 2575 if (!IsProvablyNotDerivedFrom(*this, BaseRecord, MemberRecord)) 2576 return false; 2577 } 2578 2579 DiagnoseQualifiedMemberReference(*this, BaseExpr, BaseType, SS, R); 2580 return true; 2581} 2582 2583static bool 2584LookupMemberExprInRecord(Sema &SemaRef, LookupResult &R, 2585 SourceRange BaseRange, const RecordType *RTy, 2586 SourceLocation OpLoc, CXXScopeSpec &SS) { 2587 RecordDecl *RDecl = RTy->getDecl(); 2588 if (SemaRef.RequireCompleteType(OpLoc, QualType(RTy, 0), 2589 SemaRef.PDiag(diag::err_typecheck_incomplete_tag) 2590 << BaseRange)) 2591 return true; 2592 2593 DeclContext *DC = RDecl; 2594 if (SS.isSet()) { 2595 // If the member name was a qualified-id, look into the 2596 // nested-name-specifier. 2597 DC = SemaRef.computeDeclContext(SS, false); 2598 2599 if (SemaRef.RequireCompleteDeclContext(SS, DC)) { 2600 SemaRef.Diag(SS.getRange().getEnd(), diag::err_typecheck_incomplete_tag) 2601 << SS.getRange() << DC; 2602 return true; 2603 } 2604 2605 assert(DC && "Cannot handle non-computable dependent contexts in lookup"); 2606 2607 if (!isa<TypeDecl>(DC)) { 2608 SemaRef.Diag(R.getNameLoc(), diag::err_qualified_member_nonclass) 2609 << DC << SS.getRange(); 2610 return true; 2611 } 2612 } 2613 2614 // The record definition is complete, now look up the member. 2615 SemaRef.LookupQualifiedName(R, DC); 2616 2617 if (!R.empty()) 2618 return false; 2619 2620 // We didn't find anything with the given name, so try to correct 2621 // for typos. 2622 DeclarationName Name = R.getLookupName(); 2623 if (SemaRef.CorrectTypo(R, 0, &SS, DC, false, Sema::CTC_MemberLookup) && 2624 !R.empty() && 2625 (isa<ValueDecl>(*R.begin()) || isa<FunctionTemplateDecl>(*R.begin()))) { 2626 SemaRef.Diag(R.getNameLoc(), diag::err_no_member_suggest) 2627 << Name << DC << R.getLookupName() << SS.getRange() 2628 << FixItHint::CreateReplacement(R.getNameLoc(), 2629 R.getLookupName().getAsString()); 2630 if (NamedDecl *ND = R.getAsSingle<NamedDecl>()) 2631 SemaRef.Diag(ND->getLocation(), diag::note_previous_decl) 2632 << ND->getDeclName(); 2633 return false; 2634 } else { 2635 R.clear(); 2636 } 2637 2638 return false; 2639} 2640 2641Sema::OwningExprResult 2642Sema::BuildMemberReferenceExpr(ExprArg BaseArg, QualType BaseType, 2643 SourceLocation OpLoc, bool IsArrow, 2644 CXXScopeSpec &SS, 2645 NamedDecl *FirstQualifierInScope, 2646 DeclarationName Name, SourceLocation NameLoc, 2647 const TemplateArgumentListInfo *TemplateArgs) { 2648 Expr *Base = BaseArg.takeAs<Expr>(); 2649 2650 if (BaseType->isDependentType() || 2651 (SS.isSet() && isDependentScopeSpecifier(SS))) 2652 return ActOnDependentMemberExpr(ExprArg(*this, Base), BaseType, 2653 IsArrow, OpLoc, 2654 SS, FirstQualifierInScope, 2655 Name, NameLoc, 2656 TemplateArgs); 2657 2658 LookupResult R(*this, Name, NameLoc, LookupMemberName); 2659 2660 // Implicit member accesses. 2661 if (!Base) { 2662 QualType RecordTy = BaseType; 2663 if (IsArrow) RecordTy = RecordTy->getAs<PointerType>()->getPointeeType(); 2664 if (LookupMemberExprInRecord(*this, R, SourceRange(), 2665 RecordTy->getAs<RecordType>(), 2666 OpLoc, SS)) 2667 return ExprError(); 2668 2669 // Explicit member accesses. 2670 } else { 2671 OwningExprResult Result = 2672 LookupMemberExpr(R, Base, IsArrow, OpLoc, 2673 SS, /*ObjCImpDecl*/ DeclPtrTy()); 2674 2675 if (Result.isInvalid()) { 2676 Owned(Base); 2677 return ExprError(); 2678 } 2679 2680 if (Result.get()) 2681 return move(Result); 2682 2683 // LookupMemberExpr can modify Base, and thus change BaseType 2684 BaseType = Base->getType(); 2685 } 2686 2687 return BuildMemberReferenceExpr(ExprArg(*this, Base), BaseType, 2688 OpLoc, IsArrow, SS, FirstQualifierInScope, 2689 R, TemplateArgs); 2690} 2691 2692Sema::OwningExprResult 2693Sema::BuildMemberReferenceExpr(ExprArg Base, QualType BaseExprType, 2694 SourceLocation OpLoc, bool IsArrow, 2695 const CXXScopeSpec &SS, 2696 NamedDecl *FirstQualifierInScope, 2697 LookupResult &R, 2698 const TemplateArgumentListInfo *TemplateArgs, 2699 bool SuppressQualifierCheck) { 2700 Expr *BaseExpr = Base.takeAs<Expr>(); 2701 QualType BaseType = BaseExprType; 2702 if (IsArrow) { 2703 assert(BaseType->isPointerType()); 2704 BaseType = BaseType->getAs<PointerType>()->getPointeeType(); 2705 } 2706 R.setBaseObjectType(BaseType); 2707 2708 NestedNameSpecifier *Qualifier = 2709 static_cast<NestedNameSpecifier*>(SS.getScopeRep()); 2710 DeclarationName MemberName = R.getLookupName(); 2711 SourceLocation MemberLoc = R.getNameLoc(); 2712 2713 if (R.isAmbiguous()) 2714 return ExprError(); 2715 2716 if (R.empty()) { 2717 // Rederive where we looked up. 2718 DeclContext *DC = (SS.isSet() 2719 ? computeDeclContext(SS, false) 2720 : BaseType->getAs<RecordType>()->getDecl()); 2721 2722 Diag(R.getNameLoc(), diag::err_no_member) 2723 << MemberName << DC 2724 << (BaseExpr ? BaseExpr->getSourceRange() : SourceRange()); 2725 return ExprError(); 2726 } 2727 2728 // Diagnose lookups that find only declarations from a non-base 2729 // type. This is possible for either qualified lookups (which may 2730 // have been qualified with an unrelated type) or implicit member 2731 // expressions (which were found with unqualified lookup and thus 2732 // may have come from an enclosing scope). Note that it's okay for 2733 // lookup to find declarations from a non-base type as long as those 2734 // aren't the ones picked by overload resolution. 2735 if ((SS.isSet() || !BaseExpr || 2736 (isa<CXXThisExpr>(BaseExpr) && 2737 cast<CXXThisExpr>(BaseExpr)->isImplicit())) && 2738 !SuppressQualifierCheck && 2739 CheckQualifiedMemberReference(BaseExpr, BaseType, SS, R)) 2740 return ExprError(); 2741 2742 // Construct an unresolved result if we in fact got an unresolved 2743 // result. 2744 if (R.isOverloadedResult() || R.isUnresolvableResult()) { 2745 bool Dependent = 2746 BaseExprType->isDependentType() || 2747 R.isUnresolvableResult() || 2748 OverloadExpr::ComputeDependence(R.begin(), R.end(), TemplateArgs); 2749 2750 // Suppress any lookup-related diagnostics; we'll do these when we 2751 // pick a member. 2752 R.suppressDiagnostics(); 2753 2754 UnresolvedMemberExpr *MemExpr 2755 = UnresolvedMemberExpr::Create(Context, Dependent, 2756 R.isUnresolvableResult(), 2757 BaseExpr, BaseExprType, 2758 IsArrow, OpLoc, 2759 Qualifier, SS.getRange(), 2760 MemberName, MemberLoc, 2761 TemplateArgs); 2762 MemExpr->addDecls(R.begin(), R.end()); 2763 2764 return Owned(MemExpr); 2765 } 2766 2767 assert(R.isSingleResult()); 2768 DeclAccessPair FoundDecl = R.begin().getPair(); 2769 NamedDecl *MemberDecl = R.getFoundDecl(); 2770 2771 // FIXME: diagnose the presence of template arguments now. 2772 2773 // If the decl being referenced had an error, return an error for this 2774 // sub-expr without emitting another error, in order to avoid cascading 2775 // error cases. 2776 if (MemberDecl->isInvalidDecl()) 2777 return ExprError(); 2778 2779 // Handle the implicit-member-access case. 2780 if (!BaseExpr) { 2781 // If this is not an instance member, convert to a non-member access. 2782 if (!MemberDecl->isCXXInstanceMember()) 2783 return BuildDeclarationNameExpr(SS, R.getNameLoc(), MemberDecl); 2784 2785 SourceLocation Loc = R.getNameLoc(); 2786 if (SS.getRange().isValid()) 2787 Loc = SS.getRange().getBegin(); 2788 BaseExpr = new (Context) CXXThisExpr(Loc, BaseExprType,/*isImplicit=*/true); 2789 } 2790 2791 bool ShouldCheckUse = true; 2792 if (CXXMethodDecl *MD = dyn_cast<CXXMethodDecl>(MemberDecl)) { 2793 // Don't diagnose the use of a virtual member function unless it's 2794 // explicitly qualified. 2795 if (MD->isVirtual() && !SS.isSet()) 2796 ShouldCheckUse = false; 2797 } 2798 2799 // Check the use of this member. 2800 if (ShouldCheckUse && DiagnoseUseOfDecl(MemberDecl, MemberLoc)) { 2801 Owned(BaseExpr); 2802 return ExprError(); 2803 } 2804 2805 if (FieldDecl *FD = dyn_cast<FieldDecl>(MemberDecl)) { 2806 // We may have found a field within an anonymous union or struct 2807 // (C++ [class.union]). 2808 if (cast<RecordDecl>(FD->getDeclContext())->isAnonymousStructOrUnion() && 2809 !BaseType->getAs<RecordType>()->getDecl()->isAnonymousStructOrUnion()) 2810 return BuildAnonymousStructUnionMemberReference(MemberLoc, FD, 2811 BaseExpr, OpLoc); 2812 2813 // Figure out the type of the member; see C99 6.5.2.3p3, C++ [expr.ref] 2814 QualType MemberType = FD->getType(); 2815 if (const ReferenceType *Ref = MemberType->getAs<ReferenceType>()) 2816 MemberType = Ref->getPointeeType(); 2817 else { 2818 Qualifiers BaseQuals = BaseType.getQualifiers(); 2819 BaseQuals.removeObjCGCAttr(); 2820 if (FD->isMutable()) BaseQuals.removeConst(); 2821 2822 Qualifiers MemberQuals 2823 = Context.getCanonicalType(MemberType).getQualifiers(); 2824 2825 Qualifiers Combined = BaseQuals + MemberQuals; 2826 if (Combined != MemberQuals) 2827 MemberType = Context.getQualifiedType(MemberType, Combined); 2828 } 2829 2830 MarkDeclarationReferenced(MemberLoc, FD); 2831 if (PerformObjectMemberConversion(BaseExpr, Qualifier, FoundDecl, FD)) 2832 return ExprError(); 2833 return Owned(BuildMemberExpr(Context, BaseExpr, IsArrow, SS, 2834 FD, FoundDecl, MemberLoc, MemberType)); 2835 } 2836 2837 if (VarDecl *Var = dyn_cast<VarDecl>(MemberDecl)) { 2838 MarkDeclarationReferenced(MemberLoc, Var); 2839 return Owned(BuildMemberExpr(Context, BaseExpr, IsArrow, SS, 2840 Var, FoundDecl, MemberLoc, 2841 Var->getType().getNonReferenceType())); 2842 } 2843 2844 if (FunctionDecl *MemberFn = dyn_cast<FunctionDecl>(MemberDecl)) { 2845 MarkDeclarationReferenced(MemberLoc, MemberDecl); 2846 return Owned(BuildMemberExpr(Context, BaseExpr, IsArrow, SS, 2847 MemberFn, FoundDecl, MemberLoc, 2848 MemberFn->getType())); 2849 } 2850 2851 if (EnumConstantDecl *Enum = dyn_cast<EnumConstantDecl>(MemberDecl)) { 2852 MarkDeclarationReferenced(MemberLoc, MemberDecl); 2853 return Owned(BuildMemberExpr(Context, BaseExpr, IsArrow, SS, 2854 Enum, FoundDecl, MemberLoc, Enum->getType())); 2855 } 2856 2857 Owned(BaseExpr); 2858 2859 // We found something that we didn't expect. Complain. 2860 if (isa<TypeDecl>(MemberDecl)) 2861 Diag(MemberLoc,diag::err_typecheck_member_reference_type) 2862 << MemberName << BaseType << int(IsArrow); 2863 else 2864 Diag(MemberLoc, diag::err_typecheck_member_reference_unknown) 2865 << MemberName << BaseType << int(IsArrow); 2866 2867 Diag(MemberDecl->getLocation(), diag::note_member_declared_here) 2868 << MemberName; 2869 R.suppressDiagnostics(); 2870 return ExprError(); 2871} 2872 2873/// Look up the given member of the given non-type-dependent 2874/// expression. This can return in one of two ways: 2875/// * If it returns a sentinel null-but-valid result, the caller will 2876/// assume that lookup was performed and the results written into 2877/// the provided structure. It will take over from there. 2878/// * Otherwise, the returned expression will be produced in place of 2879/// an ordinary member expression. 2880/// 2881/// The ObjCImpDecl bit is a gross hack that will need to be properly 2882/// fixed for ObjC++. 2883Sema::OwningExprResult 2884Sema::LookupMemberExpr(LookupResult &R, Expr *&BaseExpr, 2885 bool &IsArrow, SourceLocation OpLoc, 2886 CXXScopeSpec &SS, 2887 DeclPtrTy ObjCImpDecl) { 2888 assert(BaseExpr && "no base expression"); 2889 2890 // Perform default conversions. 2891 DefaultFunctionArrayConversion(BaseExpr); 2892 2893 QualType BaseType = BaseExpr->getType(); 2894 assert(!BaseType->isDependentType()); 2895 2896 DeclarationName MemberName = R.getLookupName(); 2897 SourceLocation MemberLoc = R.getNameLoc(); 2898 2899 // If the user is trying to apply -> or . to a function pointer 2900 // type, it's probably because they forgot parentheses to call that 2901 // function. Suggest the addition of those parentheses, build the 2902 // call, and continue on. 2903 if (const PointerType *Ptr = BaseType->getAs<PointerType>()) { 2904 if (const FunctionProtoType *Fun 2905 = Ptr->getPointeeType()->getAs<FunctionProtoType>()) { 2906 QualType ResultTy = Fun->getResultType(); 2907 if (Fun->getNumArgs() == 0 && 2908 ((!IsArrow && ResultTy->isRecordType()) || 2909 (IsArrow && ResultTy->isPointerType() && 2910 ResultTy->getAs<PointerType>()->getPointeeType() 2911 ->isRecordType()))) { 2912 SourceLocation Loc = PP.getLocForEndOfToken(BaseExpr->getLocEnd()); 2913 Diag(Loc, diag::err_member_reference_needs_call) 2914 << QualType(Fun, 0) 2915 << FixItHint::CreateInsertion(Loc, "()"); 2916 2917 OwningExprResult NewBase 2918 = ActOnCallExpr(0, ExprArg(*this, BaseExpr), Loc, 2919 MultiExprArg(*this, 0, 0), 0, Loc); 2920 if (NewBase.isInvalid()) 2921 return ExprError(); 2922 2923 BaseExpr = NewBase.takeAs<Expr>(); 2924 DefaultFunctionArrayConversion(BaseExpr); 2925 BaseType = BaseExpr->getType(); 2926 } 2927 } 2928 } 2929 2930 // If this is an Objective-C pseudo-builtin and a definition is provided then 2931 // use that. 2932 if (BaseType->isObjCIdType()) { 2933 if (IsArrow) { 2934 // Handle the following exceptional case PObj->isa. 2935 if (const ObjCObjectPointerType *OPT = 2936 BaseType->getAs<ObjCObjectPointerType>()) { 2937 if (OPT->getObjectType()->isObjCId() && 2938 MemberName.getAsIdentifierInfo()->isStr("isa")) 2939 return Owned(new (Context) ObjCIsaExpr(BaseExpr, true, MemberLoc, 2940 Context.getObjCClassType())); 2941 } 2942 } 2943 // We have an 'id' type. Rather than fall through, we check if this 2944 // is a reference to 'isa'. 2945 if (BaseType != Context.ObjCIdRedefinitionType) { 2946 BaseType = Context.ObjCIdRedefinitionType; 2947 ImpCastExprToType(BaseExpr, BaseType, CastExpr::CK_BitCast); 2948 } 2949 } 2950 2951 // If this is an Objective-C pseudo-builtin and a definition is provided then 2952 // use that. 2953 if (Context.isObjCSelType(BaseType)) { 2954 // We have an 'SEL' type. Rather than fall through, we check if this 2955 // is a reference to 'sel_id'. 2956 if (BaseType != Context.ObjCSelRedefinitionType) { 2957 BaseType = Context.ObjCSelRedefinitionType; 2958 ImpCastExprToType(BaseExpr, BaseType, CastExpr::CK_BitCast); 2959 } 2960 } 2961 2962 assert(!BaseType.isNull() && "no type for member expression"); 2963 2964 // Handle properties on ObjC 'Class' types. 2965 if (!IsArrow && BaseType->isObjCClassType()) { 2966 // Also must look for a getter name which uses property syntax. 2967 IdentifierInfo *Member = MemberName.getAsIdentifierInfo(); 2968 Selector Sel = PP.getSelectorTable().getNullarySelector(Member); 2969 if (ObjCMethodDecl *MD = getCurMethodDecl()) { 2970 ObjCInterfaceDecl *IFace = MD->getClassInterface(); 2971 ObjCMethodDecl *Getter; 2972 // FIXME: need to also look locally in the implementation. 2973 if ((Getter = IFace->lookupClassMethod(Sel))) { 2974 // Check the use of this method. 2975 if (DiagnoseUseOfDecl(Getter, MemberLoc)) 2976 return ExprError(); 2977 } 2978 // If we found a getter then this may be a valid dot-reference, we 2979 // will look for the matching setter, in case it is needed. 2980 Selector SetterSel = 2981 SelectorTable::constructSetterName(PP.getIdentifierTable(), 2982 PP.getSelectorTable(), Member); 2983 ObjCMethodDecl *Setter = IFace->lookupClassMethod(SetterSel); 2984 if (!Setter) { 2985 // If this reference is in an @implementation, also check for 'private' 2986 // methods. 2987 Setter = IFace->lookupPrivateInstanceMethod(SetterSel); 2988 } 2989 // Look through local category implementations associated with the class. 2990 if (!Setter) 2991 Setter = IFace->getCategoryClassMethod(SetterSel); 2992 2993 if (Setter && DiagnoseUseOfDecl(Setter, MemberLoc)) 2994 return ExprError(); 2995 2996 if (Getter || Setter) { 2997 QualType PType; 2998 2999 if (Getter) 3000 PType = Getter->getResultType(); 3001 else 3002 // Get the expression type from Setter's incoming parameter. 3003 PType = (*(Setter->param_end() -1))->getType(); 3004 // FIXME: we must check that the setter has property type. 3005 return Owned(new (Context) ObjCImplicitSetterGetterRefExpr(Getter, 3006 PType, 3007 Setter, MemberLoc, BaseExpr)); 3008 } 3009 return ExprError(Diag(MemberLoc, diag::err_property_not_found) 3010 << MemberName << BaseType); 3011 } 3012 } 3013 3014 if (BaseType->isObjCClassType() && 3015 BaseType != Context.ObjCClassRedefinitionType) { 3016 BaseType = Context.ObjCClassRedefinitionType; 3017 ImpCastExprToType(BaseExpr, BaseType, CastExpr::CK_BitCast); 3018 } 3019 3020 if (IsArrow) { 3021 if (const PointerType *PT = BaseType->getAs<PointerType>()) 3022 BaseType = PT->getPointeeType(); 3023 else if (BaseType->isObjCObjectPointerType()) 3024 ; 3025 else if (BaseType->isRecordType()) { 3026 // Recover from arrow accesses to records, e.g.: 3027 // struct MyRecord foo; 3028 // foo->bar 3029 // This is actually well-formed in C++ if MyRecord has an 3030 // overloaded operator->, but that should have been dealt with 3031 // by now. 3032 Diag(OpLoc, diag::err_typecheck_member_reference_suggestion) 3033 << BaseType << int(IsArrow) << BaseExpr->getSourceRange() 3034 << FixItHint::CreateReplacement(OpLoc, "."); 3035 IsArrow = false; 3036 } else { 3037 Diag(MemberLoc, diag::err_typecheck_member_reference_arrow) 3038 << BaseType << BaseExpr->getSourceRange(); 3039 return ExprError(); 3040 } 3041 } else { 3042 // Recover from dot accesses to pointers, e.g.: 3043 // type *foo; 3044 // foo.bar 3045 // This is actually well-formed in two cases: 3046 // - 'type' is an Objective C type 3047 // - 'bar' is a pseudo-destructor name which happens to refer to 3048 // the appropriate pointer type 3049 if (MemberName.getNameKind() != DeclarationName::CXXDestructorName) { 3050 const PointerType *PT = BaseType->getAs<PointerType>(); 3051 if (PT && PT->getPointeeType()->isRecordType()) { 3052 Diag(OpLoc, diag::err_typecheck_member_reference_suggestion) 3053 << BaseType << int(IsArrow) << BaseExpr->getSourceRange() 3054 << FixItHint::CreateReplacement(OpLoc, "->"); 3055 BaseType = PT->getPointeeType(); 3056 IsArrow = true; 3057 } 3058 } 3059 } 3060 3061 // Handle field access to simple records. 3062 if (const RecordType *RTy = BaseType->getAs<RecordType>()) { 3063 if (LookupMemberExprInRecord(*this, R, BaseExpr->getSourceRange(), 3064 RTy, OpLoc, SS)) 3065 return ExprError(); 3066 return Owned((Expr*) 0); 3067 } 3068 3069 // Handle access to Objective-C instance variables, such as "Obj->ivar" and 3070 // (*Obj).ivar. 3071 if ((IsArrow && BaseType->isObjCObjectPointerType()) || 3072 (!IsArrow && BaseType->isObjCObjectType())) { 3073 const ObjCObjectPointerType *OPT = BaseType->getAs<ObjCObjectPointerType>(); 3074 ObjCInterfaceDecl *IDecl = 3075 OPT ? OPT->getInterfaceDecl() 3076 : BaseType->getAs<ObjCObjectType>()->getInterface(); 3077 if (IDecl) { 3078 IdentifierInfo *Member = MemberName.getAsIdentifierInfo(); 3079 3080 ObjCInterfaceDecl *ClassDeclared; 3081 ObjCIvarDecl *IV = IDecl->lookupInstanceVariable(Member, ClassDeclared); 3082 3083 if (!IV) { 3084 // Attempt to correct for typos in ivar names. 3085 LookupResult Res(*this, R.getLookupName(), R.getNameLoc(), 3086 LookupMemberName); 3087 if (CorrectTypo(Res, 0, 0, IDecl, false, CTC_MemberLookup) && 3088 (IV = Res.getAsSingle<ObjCIvarDecl>())) { 3089 Diag(R.getNameLoc(), 3090 diag::err_typecheck_member_reference_ivar_suggest) 3091 << IDecl->getDeclName() << MemberName << IV->getDeclName() 3092 << FixItHint::CreateReplacement(R.getNameLoc(), 3093 IV->getNameAsString()); 3094 Diag(IV->getLocation(), diag::note_previous_decl) 3095 << IV->getDeclName(); 3096 } 3097 } 3098 3099 if (IV) { 3100 // If the decl being referenced had an error, return an error for this 3101 // sub-expr without emitting another error, in order to avoid cascading 3102 // error cases. 3103 if (IV->isInvalidDecl()) 3104 return ExprError(); 3105 3106 // Check whether we can reference this field. 3107 if (DiagnoseUseOfDecl(IV, MemberLoc)) 3108 return ExprError(); 3109 if (IV->getAccessControl() != ObjCIvarDecl::Public && 3110 IV->getAccessControl() != ObjCIvarDecl::Package) { 3111 ObjCInterfaceDecl *ClassOfMethodDecl = 0; 3112 if (ObjCMethodDecl *MD = getCurMethodDecl()) 3113 ClassOfMethodDecl = MD->getClassInterface(); 3114 else if (ObjCImpDecl && getCurFunctionDecl()) { 3115 // Case of a c-function declared inside an objc implementation. 3116 // FIXME: For a c-style function nested inside an objc implementation 3117 // class, there is no implementation context available, so we pass 3118 // down the context as argument to this routine. Ideally, this context 3119 // need be passed down in the AST node and somehow calculated from the 3120 // AST for a function decl. 3121 Decl *ImplDecl = ObjCImpDecl.getAs<Decl>(); 3122 if (ObjCImplementationDecl *IMPD = 3123 dyn_cast<ObjCImplementationDecl>(ImplDecl)) 3124 ClassOfMethodDecl = IMPD->getClassInterface(); 3125 else if (ObjCCategoryImplDecl* CatImplClass = 3126 dyn_cast<ObjCCategoryImplDecl>(ImplDecl)) 3127 ClassOfMethodDecl = CatImplClass->getClassInterface(); 3128 } 3129 3130 if (IV->getAccessControl() == ObjCIvarDecl::Private) { 3131 if (ClassDeclared != IDecl || 3132 ClassOfMethodDecl != ClassDeclared) 3133 Diag(MemberLoc, diag::error_private_ivar_access) 3134 << IV->getDeclName(); 3135 } else if (!IDecl->isSuperClassOf(ClassOfMethodDecl)) 3136 // @protected 3137 Diag(MemberLoc, diag::error_protected_ivar_access) 3138 << IV->getDeclName(); 3139 } 3140 3141 return Owned(new (Context) ObjCIvarRefExpr(IV, IV->getType(), 3142 MemberLoc, BaseExpr, 3143 IsArrow)); 3144 } 3145 return ExprError(Diag(MemberLoc, diag::err_typecheck_member_reference_ivar) 3146 << IDecl->getDeclName() << MemberName 3147 << BaseExpr->getSourceRange()); 3148 } 3149 } 3150 // Handle properties on 'id' and qualified "id". 3151 if (!IsArrow && (BaseType->isObjCIdType() || 3152 BaseType->isObjCQualifiedIdType())) { 3153 const ObjCObjectPointerType *QIdTy = BaseType->getAs<ObjCObjectPointerType>(); 3154 IdentifierInfo *Member = MemberName.getAsIdentifierInfo(); 3155 3156 // Check protocols on qualified interfaces. 3157 Selector Sel = PP.getSelectorTable().getNullarySelector(Member); 3158 if (Decl *PMDecl = FindGetterNameDecl(QIdTy, Member, Sel, Context)) { 3159 if (ObjCPropertyDecl *PD = dyn_cast<ObjCPropertyDecl>(PMDecl)) { 3160 // Check the use of this declaration 3161 if (DiagnoseUseOfDecl(PD, MemberLoc)) 3162 return ExprError(); 3163 3164 return Owned(new (Context) ObjCPropertyRefExpr(PD, PD->getType(), 3165 MemberLoc, BaseExpr)); 3166 } 3167 if (ObjCMethodDecl *OMD = dyn_cast<ObjCMethodDecl>(PMDecl)) { 3168 // Check the use of this method. 3169 if (DiagnoseUseOfDecl(OMD, MemberLoc)) 3170 return ExprError(); 3171 3172 return Owned(ObjCMessageExpr::Create(Context, 3173 OMD->getResultType().getNonReferenceType(), 3174 OpLoc, BaseExpr, Sel, 3175 OMD, NULL, 0, MemberLoc)); 3176 } 3177 } 3178 3179 return ExprError(Diag(MemberLoc, diag::err_property_not_found) 3180 << MemberName << BaseType); 3181 } 3182 3183 // Handle Objective-C property access, which is "Obj.property" where Obj is a 3184 // pointer to a (potentially qualified) interface type. 3185 if (!IsArrow) 3186 if (const ObjCObjectPointerType *OPT = 3187 BaseType->getAsObjCInterfacePointerType()) 3188 return HandleExprPropertyRefExpr(OPT, BaseExpr, MemberName, MemberLoc); 3189 3190 // Handle the following exceptional case (*Obj).isa. 3191 if (!IsArrow && 3192 BaseType->isObjCObjectType() && 3193 BaseType->getAs<ObjCObjectType>()->isObjCId() && 3194 MemberName.getAsIdentifierInfo()->isStr("isa")) 3195 return Owned(new (Context) ObjCIsaExpr(BaseExpr, false, MemberLoc, 3196 Context.getObjCClassType())); 3197 3198 // Handle 'field access' to vectors, such as 'V.xx'. 3199 if (BaseType->isExtVectorType()) { 3200 IdentifierInfo *Member = MemberName.getAsIdentifierInfo(); 3201 QualType ret = CheckExtVectorComponent(BaseType, OpLoc, Member, MemberLoc); 3202 if (ret.isNull()) 3203 return ExprError(); 3204 return Owned(new (Context) ExtVectorElementExpr(ret, BaseExpr, *Member, 3205 MemberLoc)); 3206 } 3207 3208 Diag(MemberLoc, diag::err_typecheck_member_reference_struct_union) 3209 << BaseType << BaseExpr->getSourceRange(); 3210 3211 return ExprError(); 3212} 3213 3214/// The main callback when the parser finds something like 3215/// expression . [nested-name-specifier] identifier 3216/// expression -> [nested-name-specifier] identifier 3217/// where 'identifier' encompasses a fairly broad spectrum of 3218/// possibilities, including destructor and operator references. 3219/// 3220/// \param OpKind either tok::arrow or tok::period 3221/// \param HasTrailingLParen whether the next token is '(', which 3222/// is used to diagnose mis-uses of special members that can 3223/// only be called 3224/// \param ObjCImpDecl the current ObjC @implementation decl; 3225/// this is an ugly hack around the fact that ObjC @implementations 3226/// aren't properly put in the context chain 3227Sema::OwningExprResult Sema::ActOnMemberAccessExpr(Scope *S, ExprArg BaseArg, 3228 SourceLocation OpLoc, 3229 tok::TokenKind OpKind, 3230 CXXScopeSpec &SS, 3231 UnqualifiedId &Id, 3232 DeclPtrTy ObjCImpDecl, 3233 bool HasTrailingLParen) { 3234 if (SS.isSet() && SS.isInvalid()) 3235 return ExprError(); 3236 3237 TemplateArgumentListInfo TemplateArgsBuffer; 3238 3239 // Decompose the name into its component parts. 3240 DeclarationName Name; 3241 SourceLocation NameLoc; 3242 const TemplateArgumentListInfo *TemplateArgs; 3243 DecomposeUnqualifiedId(*this, Id, TemplateArgsBuffer, 3244 Name, NameLoc, TemplateArgs); 3245 3246 bool IsArrow = (OpKind == tok::arrow); 3247 3248 NamedDecl *FirstQualifierInScope 3249 = (!SS.isSet() ? 0 : FindFirstQualifierInScope(S, 3250 static_cast<NestedNameSpecifier*>(SS.getScopeRep()))); 3251 3252 // This is a postfix expression, so get rid of ParenListExprs. 3253 BaseArg = MaybeConvertParenListExprToParenExpr(S, move(BaseArg)); 3254 3255 Expr *Base = BaseArg.takeAs<Expr>(); 3256 OwningExprResult Result(*this); 3257 if (Base->getType()->isDependentType() || Name.isDependentName() || 3258 isDependentScopeSpecifier(SS)) { 3259 Result = ActOnDependentMemberExpr(ExprArg(*this, Base), Base->getType(), 3260 IsArrow, OpLoc, 3261 SS, FirstQualifierInScope, 3262 Name, NameLoc, 3263 TemplateArgs); 3264 } else { 3265 LookupResult R(*this, Name, NameLoc, LookupMemberName); 3266 if (TemplateArgs) { 3267 // Re-use the lookup done for the template name. 3268 DecomposeTemplateName(R, Id); 3269 3270 // Re-derive the naming class. 3271 if (SS.isSet()) { 3272 NestedNameSpecifier *Qualifier 3273 = static_cast<NestedNameSpecifier *>(SS.getScopeRep()); 3274 if (const Type *Ty = Qualifier->getAsType()) 3275 if (CXXRecordDecl *NamingClass = Ty->getAsCXXRecordDecl()) 3276 R.setNamingClass(NamingClass); 3277 } else { 3278 QualType BaseType = Base->getType(); 3279 if (const PointerType *Ptr = BaseType->getAs<PointerType>()) 3280 BaseType = Ptr->getPointeeType(); 3281 if (CXXRecordDecl *NamingClass = BaseType->getAsCXXRecordDecl()) 3282 R.setNamingClass(NamingClass); 3283 } 3284 } else { 3285 Result = LookupMemberExpr(R, Base, IsArrow, OpLoc, 3286 SS, ObjCImpDecl); 3287 3288 if (Result.isInvalid()) { 3289 Owned(Base); 3290 return ExprError(); 3291 } 3292 3293 if (Result.get()) { 3294 // The only way a reference to a destructor can be used is to 3295 // immediately call it, which falls into this case. If the 3296 // next token is not a '(', produce a diagnostic and build the 3297 // call now. 3298 if (!HasTrailingLParen && 3299 Id.getKind() == UnqualifiedId::IK_DestructorName) 3300 return DiagnoseDtorReference(NameLoc, move(Result)); 3301 3302 return move(Result); 3303 } 3304 } 3305 3306 Result = BuildMemberReferenceExpr(ExprArg(*this, Base), Base->getType(), 3307 OpLoc, IsArrow, SS, FirstQualifierInScope, 3308 R, TemplateArgs); 3309 } 3310 3311 return move(Result); 3312} 3313 3314Sema::OwningExprResult Sema::BuildCXXDefaultArgExpr(SourceLocation CallLoc, 3315 FunctionDecl *FD, 3316 ParmVarDecl *Param) { 3317 if (Param->hasUnparsedDefaultArg()) { 3318 Diag (CallLoc, 3319 diag::err_use_of_default_argument_to_function_declared_later) << 3320 FD << cast<CXXRecordDecl>(FD->getDeclContext())->getDeclName(); 3321 Diag(UnparsedDefaultArgLocs[Param], 3322 diag::note_default_argument_declared_here); 3323 } else { 3324 if (Param->hasUninstantiatedDefaultArg()) { 3325 Expr *UninstExpr = Param->getUninstantiatedDefaultArg(); 3326 3327 // Instantiate the expression. 3328 MultiLevelTemplateArgumentList ArgList 3329 = getTemplateInstantiationArgs(FD, 0, /*RelativeToPrimary=*/true); 3330 3331 InstantiatingTemplate Inst(*this, CallLoc, Param, 3332 ArgList.getInnermost().getFlatArgumentList(), 3333 ArgList.getInnermost().flat_size()); 3334 3335 OwningExprResult Result = SubstExpr(UninstExpr, ArgList); 3336 if (Result.isInvalid()) 3337 return ExprError(); 3338 3339 // Check the expression as an initializer for the parameter. 3340 InitializedEntity Entity 3341 = InitializedEntity::InitializeParameter(Param); 3342 InitializationKind Kind 3343 = InitializationKind::CreateCopy(Param->getLocation(), 3344 /*FIXME:EqualLoc*/UninstExpr->getSourceRange().getBegin()); 3345 Expr *ResultE = Result.takeAs<Expr>(); 3346 3347 InitializationSequence InitSeq(*this, Entity, Kind, &ResultE, 1); 3348 Result = InitSeq.Perform(*this, Entity, Kind, 3349 MultiExprArg(*this, (void**)&ResultE, 1)); 3350 if (Result.isInvalid()) 3351 return ExprError(); 3352 3353 // Build the default argument expression. 3354 return Owned(CXXDefaultArgExpr::Create(Context, CallLoc, Param, 3355 Result.takeAs<Expr>())); 3356 } 3357 3358 // If the default expression creates temporaries, we need to 3359 // push them to the current stack of expression temporaries so they'll 3360 // be properly destroyed. 3361 // FIXME: We should really be rebuilding the default argument with new 3362 // bound temporaries; see the comment in PR5810. 3363 for (unsigned i = 0, e = Param->getNumDefaultArgTemporaries(); i != e; ++i) 3364 ExprTemporaries.push_back(Param->getDefaultArgTemporary(i)); 3365 } 3366 3367 // We already type-checked the argument, so we know it works. 3368 return Owned(CXXDefaultArgExpr::Create(Context, CallLoc, Param)); 3369} 3370 3371/// ConvertArgumentsForCall - Converts the arguments specified in 3372/// Args/NumArgs to the parameter types of the function FDecl with 3373/// function prototype Proto. Call is the call expression itself, and 3374/// Fn is the function expression. For a C++ member function, this 3375/// routine does not attempt to convert the object argument. Returns 3376/// true if the call is ill-formed. 3377bool 3378Sema::ConvertArgumentsForCall(CallExpr *Call, Expr *Fn, 3379 FunctionDecl *FDecl, 3380 const FunctionProtoType *Proto, 3381 Expr **Args, unsigned NumArgs, 3382 SourceLocation RParenLoc) { 3383 // C99 6.5.2.2p7 - the arguments are implicitly converted, as if by 3384 // assignment, to the types of the corresponding parameter, ... 3385 unsigned NumArgsInProto = Proto->getNumArgs(); 3386 bool Invalid = false; 3387 3388 // If too few arguments are available (and we don't have default 3389 // arguments for the remaining parameters), don't make the call. 3390 if (NumArgs < NumArgsInProto) { 3391 if (!FDecl || NumArgs < FDecl->getMinRequiredArguments()) 3392 return Diag(RParenLoc, diag::err_typecheck_call_too_few_args) 3393 << Fn->getType()->isBlockPointerType() 3394 << NumArgsInProto << NumArgs << Fn->getSourceRange(); 3395 Call->setNumArgs(Context, NumArgsInProto); 3396 } 3397 3398 // If too many are passed and not variadic, error on the extras and drop 3399 // them. 3400 if (NumArgs > NumArgsInProto) { 3401 if (!Proto->isVariadic()) { 3402 Diag(Args[NumArgsInProto]->getLocStart(), 3403 diag::err_typecheck_call_too_many_args) 3404 << Fn->getType()->isBlockPointerType() 3405 << NumArgsInProto << NumArgs << Fn->getSourceRange() 3406 << SourceRange(Args[NumArgsInProto]->getLocStart(), 3407 Args[NumArgs-1]->getLocEnd()); 3408 // This deletes the extra arguments. 3409 Call->setNumArgs(Context, NumArgsInProto); 3410 return true; 3411 } 3412 } 3413 llvm::SmallVector<Expr *, 8> AllArgs; 3414 VariadicCallType CallType = 3415 Proto->isVariadic() ? VariadicFunction : VariadicDoesNotApply; 3416 if (Fn->getType()->isBlockPointerType()) 3417 CallType = VariadicBlock; // Block 3418 else if (isa<MemberExpr>(Fn)) 3419 CallType = VariadicMethod; 3420 Invalid = GatherArgumentsForCall(Call->getSourceRange().getBegin(), FDecl, 3421 Proto, 0, Args, NumArgs, AllArgs, CallType); 3422 if (Invalid) 3423 return true; 3424 unsigned TotalNumArgs = AllArgs.size(); 3425 for (unsigned i = 0; i < TotalNumArgs; ++i) 3426 Call->setArg(i, AllArgs[i]); 3427 3428 return false; 3429} 3430 3431bool Sema::GatherArgumentsForCall(SourceLocation CallLoc, 3432 FunctionDecl *FDecl, 3433 const FunctionProtoType *Proto, 3434 unsigned FirstProtoArg, 3435 Expr **Args, unsigned NumArgs, 3436 llvm::SmallVector<Expr *, 8> &AllArgs, 3437 VariadicCallType CallType) { 3438 unsigned NumArgsInProto = Proto->getNumArgs(); 3439 unsigned NumArgsToCheck = NumArgs; 3440 bool Invalid = false; 3441 if (NumArgs != NumArgsInProto) 3442 // Use default arguments for missing arguments 3443 NumArgsToCheck = NumArgsInProto; 3444 unsigned ArgIx = 0; 3445 // Continue to check argument types (even if we have too few/many args). 3446 for (unsigned i = FirstProtoArg; i != NumArgsToCheck; i++) { 3447 QualType ProtoArgType = Proto->getArgType(i); 3448 3449 Expr *Arg; 3450 if (ArgIx < NumArgs) { 3451 Arg = Args[ArgIx++]; 3452 3453 if (RequireCompleteType(Arg->getSourceRange().getBegin(), 3454 ProtoArgType, 3455 PDiag(diag::err_call_incomplete_argument) 3456 << Arg->getSourceRange())) 3457 return true; 3458 3459 // Pass the argument 3460 ParmVarDecl *Param = 0; 3461 if (FDecl && i < FDecl->getNumParams()) 3462 Param = FDecl->getParamDecl(i); 3463 3464 3465 InitializedEntity Entity = 3466 Param? InitializedEntity::InitializeParameter(Param) 3467 : InitializedEntity::InitializeParameter(ProtoArgType); 3468 OwningExprResult ArgE = PerformCopyInitialization(Entity, 3469 SourceLocation(), 3470 Owned(Arg)); 3471 if (ArgE.isInvalid()) 3472 return true; 3473 3474 Arg = ArgE.takeAs<Expr>(); 3475 } else { 3476 ParmVarDecl *Param = FDecl->getParamDecl(i); 3477 3478 OwningExprResult ArgExpr = 3479 BuildCXXDefaultArgExpr(CallLoc, FDecl, Param); 3480 if (ArgExpr.isInvalid()) 3481 return true; 3482 3483 Arg = ArgExpr.takeAs<Expr>(); 3484 } 3485 AllArgs.push_back(Arg); 3486 } 3487 3488 // If this is a variadic call, handle args passed through "...". 3489 if (CallType != VariadicDoesNotApply) { 3490 // Promote the arguments (C99 6.5.2.2p7). 3491 for (unsigned i = ArgIx; i != NumArgs; ++i) { 3492 Expr *Arg = Args[i]; 3493 Invalid |= DefaultVariadicArgumentPromotion(Arg, CallType, FDecl); 3494 AllArgs.push_back(Arg); 3495 } 3496 } 3497 return Invalid; 3498} 3499 3500/// ActOnCallExpr - Handle a call to Fn with the specified array of arguments. 3501/// This provides the location of the left/right parens and a list of comma 3502/// locations. 3503Action::OwningExprResult 3504Sema::ActOnCallExpr(Scope *S, ExprArg fn, SourceLocation LParenLoc, 3505 MultiExprArg args, 3506 SourceLocation *CommaLocs, SourceLocation RParenLoc) { 3507 unsigned NumArgs = args.size(); 3508 3509 // Since this might be a postfix expression, get rid of ParenListExprs. 3510 fn = MaybeConvertParenListExprToParenExpr(S, move(fn)); 3511 3512 Expr *Fn = fn.takeAs<Expr>(); 3513 Expr **Args = reinterpret_cast<Expr**>(args.release()); 3514 assert(Fn && "no function call expression"); 3515 3516 if (getLangOptions().CPlusPlus) { 3517 // If this is a pseudo-destructor expression, build the call immediately. 3518 if (isa<CXXPseudoDestructorExpr>(Fn)) { 3519 if (NumArgs > 0) { 3520 // Pseudo-destructor calls should not have any arguments. 3521 Diag(Fn->getLocStart(), diag::err_pseudo_dtor_call_with_args) 3522 << FixItHint::CreateRemoval( 3523 SourceRange(Args[0]->getLocStart(), 3524 Args[NumArgs-1]->getLocEnd())); 3525 3526 for (unsigned I = 0; I != NumArgs; ++I) 3527 Args[I]->Destroy(Context); 3528 3529 NumArgs = 0; 3530 } 3531 3532 return Owned(new (Context) CallExpr(Context, Fn, 0, 0, Context.VoidTy, 3533 RParenLoc)); 3534 } 3535 3536 // Determine whether this is a dependent call inside a C++ template, 3537 // in which case we won't do any semantic analysis now. 3538 // FIXME: Will need to cache the results of name lookup (including ADL) in 3539 // Fn. 3540 bool Dependent = false; 3541 if (Fn->isTypeDependent()) 3542 Dependent = true; 3543 else if (Expr::hasAnyTypeDependentArguments(Args, NumArgs)) 3544 Dependent = true; 3545 3546 if (Dependent) 3547 return Owned(new (Context) CallExpr(Context, Fn, Args, NumArgs, 3548 Context.DependentTy, RParenLoc)); 3549 3550 // Determine whether this is a call to an object (C++ [over.call.object]). 3551 if (Fn->getType()->isRecordType()) 3552 return Owned(BuildCallToObjectOfClassType(S, Fn, LParenLoc, Args, NumArgs, 3553 CommaLocs, RParenLoc)); 3554 3555 Expr *NakedFn = Fn->IgnoreParens(); 3556 3557 // Determine whether this is a call to an unresolved member function. 3558 if (UnresolvedMemberExpr *MemE = dyn_cast<UnresolvedMemberExpr>(NakedFn)) { 3559 // If lookup was unresolved but not dependent (i.e. didn't find 3560 // an unresolved using declaration), it has to be an overloaded 3561 // function set, which means it must contain either multiple 3562 // declarations (all methods or method templates) or a single 3563 // method template. 3564 assert((MemE->getNumDecls() > 1) || 3565 isa<FunctionTemplateDecl>( 3566 (*MemE->decls_begin())->getUnderlyingDecl())); 3567 (void)MemE; 3568 3569 return BuildCallToMemberFunction(S, Fn, LParenLoc, Args, NumArgs, 3570 CommaLocs, RParenLoc); 3571 } 3572 3573 // Determine whether this is a call to a member function. 3574 if (MemberExpr *MemExpr = dyn_cast<MemberExpr>(NakedFn)) { 3575 NamedDecl *MemDecl = MemExpr->getMemberDecl(); 3576 if (isa<CXXMethodDecl>(MemDecl)) 3577 return BuildCallToMemberFunction(S, Fn, LParenLoc, Args, NumArgs, 3578 CommaLocs, RParenLoc); 3579 } 3580 3581 // Determine whether this is a call to a pointer-to-member function. 3582 if (BinaryOperator *BO = dyn_cast<BinaryOperator>(NakedFn)) { 3583 if (BO->getOpcode() == BinaryOperator::PtrMemD || 3584 BO->getOpcode() == BinaryOperator::PtrMemI) { 3585 if (const FunctionProtoType *FPT 3586 = BO->getType()->getAs<FunctionProtoType>()) { 3587 QualType ResultTy = FPT->getResultType().getNonReferenceType(); 3588 3589 ExprOwningPtr<CXXMemberCallExpr> 3590 TheCall(this, new (Context) CXXMemberCallExpr(Context, BO, Args, 3591 NumArgs, ResultTy, 3592 RParenLoc)); 3593 3594 if (CheckCallReturnType(FPT->getResultType(), 3595 BO->getRHS()->getSourceRange().getBegin(), 3596 TheCall.get(), 0)) 3597 return ExprError(); 3598 3599 if (ConvertArgumentsForCall(&*TheCall, BO, 0, FPT, Args, NumArgs, 3600 RParenLoc)) 3601 return ExprError(); 3602 3603 return Owned(MaybeBindToTemporary(TheCall.release()).release()); 3604 } 3605 return ExprError(Diag(Fn->getLocStart(), 3606 diag::err_typecheck_call_not_function) 3607 << Fn->getType() << Fn->getSourceRange()); 3608 } 3609 } 3610 } 3611 3612 // If we're directly calling a function, get the appropriate declaration. 3613 // Also, in C++, keep track of whether we should perform argument-dependent 3614 // lookup and whether there were any explicitly-specified template arguments. 3615 3616 Expr *NakedFn = Fn->IgnoreParens(); 3617 if (isa<UnresolvedLookupExpr>(NakedFn)) { 3618 UnresolvedLookupExpr *ULE = cast<UnresolvedLookupExpr>(NakedFn); 3619 return BuildOverloadedCallExpr(S, Fn, ULE, LParenLoc, Args, NumArgs, 3620 CommaLocs, RParenLoc); 3621 } 3622 3623 NamedDecl *NDecl = 0; 3624 if (isa<DeclRefExpr>(NakedFn)) 3625 NDecl = cast<DeclRefExpr>(NakedFn)->getDecl(); 3626 3627 return BuildResolvedCallExpr(Fn, NDecl, LParenLoc, Args, NumArgs, RParenLoc); 3628} 3629 3630/// BuildResolvedCallExpr - Build a call to a resolved expression, 3631/// i.e. an expression not of \p OverloadTy. The expression should 3632/// unary-convert to an expression of function-pointer or 3633/// block-pointer type. 3634/// 3635/// \param NDecl the declaration being called, if available 3636Sema::OwningExprResult 3637Sema::BuildResolvedCallExpr(Expr *Fn, NamedDecl *NDecl, 3638 SourceLocation LParenLoc, 3639 Expr **Args, unsigned NumArgs, 3640 SourceLocation RParenLoc) { 3641 FunctionDecl *FDecl = dyn_cast_or_null<FunctionDecl>(NDecl); 3642 3643 // Promote the function operand. 3644 UsualUnaryConversions(Fn); 3645 3646 // Make the call expr early, before semantic checks. This guarantees cleanup 3647 // of arguments and function on error. 3648 ExprOwningPtr<CallExpr> TheCall(this, new (Context) CallExpr(Context, Fn, 3649 Args, NumArgs, 3650 Context.BoolTy, 3651 RParenLoc)); 3652 3653 const FunctionType *FuncT; 3654 if (!Fn->getType()->isBlockPointerType()) { 3655 // C99 6.5.2.2p1 - "The expression that denotes the called function shall 3656 // have type pointer to function". 3657 const PointerType *PT = Fn->getType()->getAs<PointerType>(); 3658 if (PT == 0) 3659 return ExprError(Diag(LParenLoc, diag::err_typecheck_call_not_function) 3660 << Fn->getType() << Fn->getSourceRange()); 3661 FuncT = PT->getPointeeType()->getAs<FunctionType>(); 3662 } else { // This is a block call. 3663 FuncT = Fn->getType()->getAs<BlockPointerType>()->getPointeeType()-> 3664 getAs<FunctionType>(); 3665 } 3666 if (FuncT == 0) 3667 return ExprError(Diag(LParenLoc, diag::err_typecheck_call_not_function) 3668 << Fn->getType() << Fn->getSourceRange()); 3669 3670 // Check for a valid return type 3671 if (CheckCallReturnType(FuncT->getResultType(), 3672 Fn->getSourceRange().getBegin(), TheCall.get(), 3673 FDecl)) 3674 return ExprError(); 3675 3676 // We know the result type of the call, set it. 3677 TheCall->setType(FuncT->getResultType().getNonReferenceType()); 3678 3679 if (const FunctionProtoType *Proto = dyn_cast<FunctionProtoType>(FuncT)) { 3680 if (ConvertArgumentsForCall(&*TheCall, Fn, FDecl, Proto, Args, NumArgs, 3681 RParenLoc)) 3682 return ExprError(); 3683 } else { 3684 assert(isa<FunctionNoProtoType>(FuncT) && "Unknown FunctionType!"); 3685 3686 if (FDecl) { 3687 // Check if we have too few/too many template arguments, based 3688 // on our knowledge of the function definition. 3689 const FunctionDecl *Def = 0; 3690 if (FDecl->getBody(Def) && NumArgs != Def->param_size()) { 3691 const FunctionProtoType *Proto = 3692 Def->getType()->getAs<FunctionProtoType>(); 3693 if (!Proto || !(Proto->isVariadic() && NumArgs >= Def->param_size())) { 3694 Diag(RParenLoc, diag::warn_call_wrong_number_of_arguments) 3695 << (NumArgs > Def->param_size()) << FDecl << Fn->getSourceRange(); 3696 } 3697 } 3698 } 3699 3700 // Promote the arguments (C99 6.5.2.2p6). 3701 for (unsigned i = 0; i != NumArgs; i++) { 3702 Expr *Arg = Args[i]; 3703 DefaultArgumentPromotion(Arg); 3704 if (RequireCompleteType(Arg->getSourceRange().getBegin(), 3705 Arg->getType(), 3706 PDiag(diag::err_call_incomplete_argument) 3707 << Arg->getSourceRange())) 3708 return ExprError(); 3709 TheCall->setArg(i, Arg); 3710 } 3711 } 3712 3713 if (CXXMethodDecl *Method = dyn_cast_or_null<CXXMethodDecl>(FDecl)) 3714 if (!Method->isStatic()) 3715 return ExprError(Diag(LParenLoc, diag::err_member_call_without_object) 3716 << Fn->getSourceRange()); 3717 3718 // Check for sentinels 3719 if (NDecl) 3720 DiagnoseSentinelCalls(NDecl, LParenLoc, Args, NumArgs); 3721 3722 // Do special checking on direct calls to functions. 3723 if (FDecl) { 3724 if (CheckFunctionCall(FDecl, TheCall.get())) 3725 return ExprError(); 3726 3727 if (unsigned BuiltinID = FDecl->getBuiltinID()) 3728 return CheckBuiltinFunctionCall(BuiltinID, TheCall.take()); 3729 } else if (NDecl) { 3730 if (CheckBlockCall(NDecl, TheCall.get())) 3731 return ExprError(); 3732 } 3733 3734 return MaybeBindToTemporary(TheCall.take()); 3735} 3736 3737Action::OwningExprResult 3738Sema::ActOnCompoundLiteral(SourceLocation LParenLoc, TypeTy *Ty, 3739 SourceLocation RParenLoc, ExprArg InitExpr) { 3740 assert((Ty != 0) && "ActOnCompoundLiteral(): missing type"); 3741 // FIXME: put back this assert when initializers are worked out. 3742 //assert((InitExpr != 0) && "ActOnCompoundLiteral(): missing expression"); 3743 3744 TypeSourceInfo *TInfo; 3745 QualType literalType = GetTypeFromParser(Ty, &TInfo); 3746 if (!TInfo) 3747 TInfo = Context.getTrivialTypeSourceInfo(literalType); 3748 3749 return BuildCompoundLiteralExpr(LParenLoc, TInfo, RParenLoc, move(InitExpr)); 3750} 3751 3752Action::OwningExprResult 3753Sema::BuildCompoundLiteralExpr(SourceLocation LParenLoc, TypeSourceInfo *TInfo, 3754 SourceLocation RParenLoc, ExprArg InitExpr) { 3755 QualType literalType = TInfo->getType(); 3756 Expr *literalExpr = static_cast<Expr*>(InitExpr.get()); 3757 3758 if (literalType->isArrayType()) { 3759 if (literalType->isVariableArrayType()) 3760 return ExprError(Diag(LParenLoc, diag::err_variable_object_no_init) 3761 << SourceRange(LParenLoc, literalExpr->getSourceRange().getEnd())); 3762 } else if (!literalType->isDependentType() && 3763 RequireCompleteType(LParenLoc, literalType, 3764 PDiag(diag::err_typecheck_decl_incomplete_type) 3765 << SourceRange(LParenLoc, 3766 literalExpr->getSourceRange().getEnd()))) 3767 return ExprError(); 3768 3769 InitializedEntity Entity 3770 = InitializedEntity::InitializeTemporary(literalType); 3771 InitializationKind Kind 3772 = InitializationKind::CreateCast(SourceRange(LParenLoc, RParenLoc), 3773 /*IsCStyleCast=*/true); 3774 InitializationSequence InitSeq(*this, Entity, Kind, &literalExpr, 1); 3775 OwningExprResult Result = InitSeq.Perform(*this, Entity, Kind, 3776 MultiExprArg(*this, (void**)&literalExpr, 1), 3777 &literalType); 3778 if (Result.isInvalid()) 3779 return ExprError(); 3780 InitExpr.release(); 3781 literalExpr = static_cast<Expr*>(Result.get()); 3782 3783 bool isFileScope = getCurFunctionOrMethodDecl() == 0; 3784 if (isFileScope) { // 6.5.2.5p3 3785 if (CheckForConstantInitializer(literalExpr, literalType)) 3786 return ExprError(); 3787 } 3788 3789 Result.release(); 3790 3791 return Owned(new (Context) CompoundLiteralExpr(LParenLoc, TInfo, literalType, 3792 literalExpr, isFileScope)); 3793} 3794 3795Action::OwningExprResult 3796Sema::ActOnInitList(SourceLocation LBraceLoc, MultiExprArg initlist, 3797 SourceLocation RBraceLoc) { 3798 unsigned NumInit = initlist.size(); 3799 Expr **InitList = reinterpret_cast<Expr**>(initlist.release()); 3800 3801 // Semantic analysis for initializers is done by ActOnDeclarator() and 3802 // CheckInitializer() - it requires knowledge of the object being intialized. 3803 3804 InitListExpr *E = new (Context) InitListExpr(Context, LBraceLoc, InitList, 3805 NumInit, RBraceLoc); 3806 E->setType(Context.VoidTy); // FIXME: just a place holder for now. 3807 return Owned(E); 3808} 3809 3810static CastExpr::CastKind getScalarCastKind(ASTContext &Context, 3811 QualType SrcTy, QualType DestTy) { 3812 if (Context.hasSameUnqualifiedType(SrcTy, DestTy)) 3813 return CastExpr::CK_NoOp; 3814 3815 if (SrcTy->hasPointerRepresentation()) { 3816 if (DestTy->hasPointerRepresentation()) 3817 return DestTy->isObjCObjectPointerType() ? 3818 CastExpr::CK_AnyPointerToObjCPointerCast : 3819 CastExpr::CK_BitCast; 3820 if (DestTy->isIntegerType()) 3821 return CastExpr::CK_PointerToIntegral; 3822 } 3823 3824 if (SrcTy->isIntegerType()) { 3825 if (DestTy->isIntegerType()) 3826 return CastExpr::CK_IntegralCast; 3827 if (DestTy->hasPointerRepresentation()) 3828 return CastExpr::CK_IntegralToPointer; 3829 if (DestTy->isRealFloatingType()) 3830 return CastExpr::CK_IntegralToFloating; 3831 } 3832 3833 if (SrcTy->isRealFloatingType()) { 3834 if (DestTy->isRealFloatingType()) 3835 return CastExpr::CK_FloatingCast; 3836 if (DestTy->isIntegerType()) 3837 return CastExpr::CK_FloatingToIntegral; 3838 } 3839 3840 // FIXME: Assert here. 3841 // assert(false && "Unhandled cast combination!"); 3842 return CastExpr::CK_Unknown; 3843} 3844 3845/// CheckCastTypes - Check type constraints for casting between types. 3846bool Sema::CheckCastTypes(SourceRange TyR, QualType castType, Expr *&castExpr, 3847 CastExpr::CastKind& Kind, 3848 CXXBaseSpecifierArray &BasePath, 3849 bool FunctionalStyle) { 3850 if (getLangOptions().CPlusPlus) 3851 return CXXCheckCStyleCast(TyR, castType, castExpr, Kind, BasePath, 3852 FunctionalStyle); 3853 3854 DefaultFunctionArrayLvalueConversion(castExpr); 3855 3856 // C99 6.5.4p2: the cast type needs to be void or scalar and the expression 3857 // type needs to be scalar. 3858 if (castType->isVoidType()) { 3859 // Cast to void allows any expr type. 3860 Kind = CastExpr::CK_ToVoid; 3861 return false; 3862 } 3863 3864 if (!castType->isScalarType() && !castType->isVectorType()) { 3865 if (Context.hasSameUnqualifiedType(castType, castExpr->getType()) && 3866 (castType->isStructureType() || castType->isUnionType())) { 3867 // GCC struct/union extension: allow cast to self. 3868 // FIXME: Check that the cast destination type is complete. 3869 Diag(TyR.getBegin(), diag::ext_typecheck_cast_nonscalar) 3870 << castType << castExpr->getSourceRange(); 3871 Kind = CastExpr::CK_NoOp; 3872 return false; 3873 } 3874 3875 if (castType->isUnionType()) { 3876 // GCC cast to union extension 3877 RecordDecl *RD = castType->getAs<RecordType>()->getDecl(); 3878 RecordDecl::field_iterator Field, FieldEnd; 3879 for (Field = RD->field_begin(), FieldEnd = RD->field_end(); 3880 Field != FieldEnd; ++Field) { 3881 if (Context.hasSameUnqualifiedType(Field->getType(), 3882 castExpr->getType())) { 3883 Diag(TyR.getBegin(), diag::ext_typecheck_cast_to_union) 3884 << castExpr->getSourceRange(); 3885 break; 3886 } 3887 } 3888 if (Field == FieldEnd) 3889 return Diag(TyR.getBegin(), diag::err_typecheck_cast_to_union_no_type) 3890 << castExpr->getType() << castExpr->getSourceRange(); 3891 Kind = CastExpr::CK_ToUnion; 3892 return false; 3893 } 3894 3895 // Reject any other conversions to non-scalar types. 3896 return Diag(TyR.getBegin(), diag::err_typecheck_cond_expect_scalar) 3897 << castType << castExpr->getSourceRange(); 3898 } 3899 3900 if (!castExpr->getType()->isScalarType() && 3901 !castExpr->getType()->isVectorType()) { 3902 return Diag(castExpr->getLocStart(), 3903 diag::err_typecheck_expect_scalar_operand) 3904 << castExpr->getType() << castExpr->getSourceRange(); 3905 } 3906 3907 if (castType->isExtVectorType()) 3908 return CheckExtVectorCast(TyR, castType, castExpr, Kind); 3909 3910 if (castType->isVectorType()) 3911 return CheckVectorCast(TyR, castType, castExpr->getType(), Kind); 3912 if (castExpr->getType()->isVectorType()) 3913 return CheckVectorCast(TyR, castExpr->getType(), castType, Kind); 3914 3915 if (isa<ObjCSelectorExpr>(castExpr)) 3916 return Diag(castExpr->getLocStart(), diag::err_cast_selector_expr); 3917 3918 if (!castType->isArithmeticType()) { 3919 QualType castExprType = castExpr->getType(); 3920 if (!castExprType->isIntegralType() && castExprType->isArithmeticType()) 3921 return Diag(castExpr->getLocStart(), 3922 diag::err_cast_pointer_from_non_pointer_int) 3923 << castExprType << castExpr->getSourceRange(); 3924 } else if (!castExpr->getType()->isArithmeticType()) { 3925 if (!castType->isIntegralType() && castType->isArithmeticType()) 3926 return Diag(castExpr->getLocStart(), 3927 diag::err_cast_pointer_to_non_pointer_int) 3928 << castType << castExpr->getSourceRange(); 3929 } 3930 3931 Kind = getScalarCastKind(Context, castExpr->getType(), castType); 3932 return false; 3933} 3934 3935bool Sema::CheckVectorCast(SourceRange R, QualType VectorTy, QualType Ty, 3936 CastExpr::CastKind &Kind) { 3937 assert(VectorTy->isVectorType() && "Not a vector type!"); 3938 3939 if (Ty->isVectorType() || Ty->isIntegerType()) { 3940 if (Context.getTypeSize(VectorTy) != Context.getTypeSize(Ty)) 3941 return Diag(R.getBegin(), 3942 Ty->isVectorType() ? 3943 diag::err_invalid_conversion_between_vectors : 3944 diag::err_invalid_conversion_between_vector_and_integer) 3945 << VectorTy << Ty << R; 3946 } else 3947 return Diag(R.getBegin(), 3948 diag::err_invalid_conversion_between_vector_and_scalar) 3949 << VectorTy << Ty << R; 3950 3951 Kind = CastExpr::CK_BitCast; 3952 return false; 3953} 3954 3955bool Sema::CheckExtVectorCast(SourceRange R, QualType DestTy, Expr *&CastExpr, 3956 CastExpr::CastKind &Kind) { 3957 assert(DestTy->isExtVectorType() && "Not an extended vector type!"); 3958 3959 QualType SrcTy = CastExpr->getType(); 3960 3961 // If SrcTy is a VectorType, the total size must match to explicitly cast to 3962 // an ExtVectorType. 3963 if (SrcTy->isVectorType()) { 3964 if (Context.getTypeSize(DestTy) != Context.getTypeSize(SrcTy)) 3965 return Diag(R.getBegin(),diag::err_invalid_conversion_between_ext_vectors) 3966 << DestTy << SrcTy << R; 3967 Kind = CastExpr::CK_BitCast; 3968 return false; 3969 } 3970 3971 // All non-pointer scalars can be cast to ExtVector type. The appropriate 3972 // conversion will take place first from scalar to elt type, and then 3973 // splat from elt type to vector. 3974 if (SrcTy->isPointerType()) 3975 return Diag(R.getBegin(), 3976 diag::err_invalid_conversion_between_vector_and_scalar) 3977 << DestTy << SrcTy << R; 3978 3979 QualType DestElemTy = DestTy->getAs<ExtVectorType>()->getElementType(); 3980 ImpCastExprToType(CastExpr, DestElemTy, 3981 getScalarCastKind(Context, SrcTy, DestElemTy)); 3982 3983 Kind = CastExpr::CK_VectorSplat; 3984 return false; 3985} 3986 3987Action::OwningExprResult 3988Sema::ActOnCastExpr(Scope *S, SourceLocation LParenLoc, TypeTy *Ty, 3989 SourceLocation RParenLoc, ExprArg Op) { 3990 assert((Ty != 0) && (Op.get() != 0) && 3991 "ActOnCastExpr(): missing type or expr"); 3992 3993 TypeSourceInfo *castTInfo; 3994 QualType castType = GetTypeFromParser(Ty, &castTInfo); 3995 if (!castTInfo) 3996 castTInfo = Context.getTrivialTypeSourceInfo(castType); 3997 3998 // If the Expr being casted is a ParenListExpr, handle it specially. 3999 Expr *castExpr = (Expr *)Op.get(); 4000 if (isa<ParenListExpr>(castExpr)) 4001 return ActOnCastOfParenListExpr(S, LParenLoc, RParenLoc, move(Op), 4002 castTInfo); 4003 4004 return BuildCStyleCastExpr(LParenLoc, castTInfo, RParenLoc, move(Op)); 4005} 4006 4007Action::OwningExprResult 4008Sema::BuildCStyleCastExpr(SourceLocation LParenLoc, TypeSourceInfo *Ty, 4009 SourceLocation RParenLoc, ExprArg Op) { 4010 Expr *castExpr = static_cast<Expr*>(Op.get()); 4011 4012 CastExpr::CastKind Kind = CastExpr::CK_Unknown; 4013 CXXBaseSpecifierArray BasePath; 4014 if (CheckCastTypes(SourceRange(LParenLoc, RParenLoc), Ty->getType(), castExpr, 4015 Kind, BasePath)) 4016 return ExprError(); 4017 4018 Op.release(); 4019 return Owned(new (Context) CStyleCastExpr(Ty->getType().getNonReferenceType(), 4020 Kind, castExpr, BasePath, Ty, 4021 LParenLoc, RParenLoc)); 4022} 4023 4024/// This is not an AltiVec-style cast, so turn the ParenListExpr into a sequence 4025/// of comma binary operators. 4026Action::OwningExprResult 4027Sema::MaybeConvertParenListExprToParenExpr(Scope *S, ExprArg EA) { 4028 Expr *expr = EA.takeAs<Expr>(); 4029 ParenListExpr *E = dyn_cast<ParenListExpr>(expr); 4030 if (!E) 4031 return Owned(expr); 4032 4033 OwningExprResult Result(*this, E->getExpr(0)); 4034 4035 for (unsigned i = 1, e = E->getNumExprs(); i != e && !Result.isInvalid(); ++i) 4036 Result = ActOnBinOp(S, E->getExprLoc(), tok::comma, move(Result), 4037 Owned(E->getExpr(i))); 4038 4039 return ActOnParenExpr(E->getLParenLoc(), E->getRParenLoc(), move(Result)); 4040} 4041 4042Action::OwningExprResult 4043Sema::ActOnCastOfParenListExpr(Scope *S, SourceLocation LParenLoc, 4044 SourceLocation RParenLoc, ExprArg Op, 4045 TypeSourceInfo *TInfo) { 4046 ParenListExpr *PE = (ParenListExpr *)Op.get(); 4047 QualType Ty = TInfo->getType(); 4048 4049 // If this is an altivec initializer, '(' type ')' '(' init, ..., init ')' 4050 // then handle it as such. 4051 if (getLangOptions().AltiVec && Ty->isVectorType()) { 4052 if (PE->getNumExprs() == 0) { 4053 Diag(PE->getExprLoc(), diag::err_altivec_empty_initializer); 4054 return ExprError(); 4055 } 4056 4057 llvm::SmallVector<Expr *, 8> initExprs; 4058 for (unsigned i = 0, e = PE->getNumExprs(); i != e; ++i) 4059 initExprs.push_back(PE->getExpr(i)); 4060 4061 // FIXME: This means that pretty-printing the final AST will produce curly 4062 // braces instead of the original commas. 4063 Op.release(); 4064 InitListExpr *E = new (Context) InitListExpr(Context, LParenLoc, 4065 &initExprs[0], 4066 initExprs.size(), RParenLoc); 4067 E->setType(Ty); 4068 return BuildCompoundLiteralExpr(LParenLoc, TInfo, RParenLoc, Owned(E)); 4069 } else { 4070 // This is not an AltiVec-style cast, so turn the ParenListExpr into a 4071 // sequence of BinOp comma operators. 4072 Op = MaybeConvertParenListExprToParenExpr(S, move(Op)); 4073 return BuildCStyleCastExpr(LParenLoc, TInfo, RParenLoc, move(Op)); 4074 } 4075} 4076 4077Action::OwningExprResult Sema::ActOnParenOrParenListExpr(SourceLocation L, 4078 SourceLocation R, 4079 MultiExprArg Val, 4080 TypeTy *TypeOfCast) { 4081 unsigned nexprs = Val.size(); 4082 Expr **exprs = reinterpret_cast<Expr**>(Val.release()); 4083 assert((exprs != 0) && "ActOnParenOrParenListExpr() missing expr list"); 4084 Expr *expr; 4085 if (nexprs == 1 && TypeOfCast && !TypeIsVectorType(TypeOfCast)) 4086 expr = new (Context) ParenExpr(L, R, exprs[0]); 4087 else 4088 expr = new (Context) ParenListExpr(Context, L, exprs, nexprs, R); 4089 return Owned(expr); 4090} 4091 4092/// Note that lhs is not null here, even if this is the gnu "x ?: y" extension. 4093/// In that case, lhs = cond. 4094/// C99 6.5.15 4095QualType Sema::CheckConditionalOperands(Expr *&Cond, Expr *&LHS, Expr *&RHS, 4096 SourceLocation QuestionLoc) { 4097 // C++ is sufficiently different to merit its own checker. 4098 if (getLangOptions().CPlusPlus) 4099 return CXXCheckConditionalOperands(Cond, LHS, RHS, QuestionLoc); 4100 4101 UsualUnaryConversions(Cond); 4102 UsualUnaryConversions(LHS); 4103 UsualUnaryConversions(RHS); 4104 QualType CondTy = Cond->getType(); 4105 QualType LHSTy = LHS->getType(); 4106 QualType RHSTy = RHS->getType(); 4107 4108 // first, check the condition. 4109 if (!CondTy->isScalarType()) { // C99 6.5.15p2 4110 Diag(Cond->getLocStart(), diag::err_typecheck_cond_expect_scalar) 4111 << CondTy; 4112 return QualType(); 4113 } 4114 4115 // Now check the two expressions. 4116 if (LHSTy->isVectorType() || RHSTy->isVectorType()) 4117 return CheckVectorOperands(QuestionLoc, LHS, RHS); 4118 4119 // If both operands have arithmetic type, do the usual arithmetic conversions 4120 // to find a common type: C99 6.5.15p3,5. 4121 if (LHSTy->isArithmeticType() && RHSTy->isArithmeticType()) { 4122 UsualArithmeticConversions(LHS, RHS); 4123 return LHS->getType(); 4124 } 4125 4126 // If both operands are the same structure or union type, the result is that 4127 // type. 4128 if (const RecordType *LHSRT = LHSTy->getAs<RecordType>()) { // C99 6.5.15p3 4129 if (const RecordType *RHSRT = RHSTy->getAs<RecordType>()) 4130 if (LHSRT->getDecl() == RHSRT->getDecl()) 4131 // "If both the operands have structure or union type, the result has 4132 // that type." This implies that CV qualifiers are dropped. 4133 return LHSTy.getUnqualifiedType(); 4134 // FIXME: Type of conditional expression must be complete in C mode. 4135 } 4136 4137 // C99 6.5.15p5: "If both operands have void type, the result has void type." 4138 // The following || allows only one side to be void (a GCC-ism). 4139 if (LHSTy->isVoidType() || RHSTy->isVoidType()) { 4140 if (!LHSTy->isVoidType()) 4141 Diag(RHS->getLocStart(), diag::ext_typecheck_cond_one_void) 4142 << RHS->getSourceRange(); 4143 if (!RHSTy->isVoidType()) 4144 Diag(LHS->getLocStart(), diag::ext_typecheck_cond_one_void) 4145 << LHS->getSourceRange(); 4146 ImpCastExprToType(LHS, Context.VoidTy, CastExpr::CK_ToVoid); 4147 ImpCastExprToType(RHS, Context.VoidTy, CastExpr::CK_ToVoid); 4148 return Context.VoidTy; 4149 } 4150 // C99 6.5.15p6 - "if one operand is a null pointer constant, the result has 4151 // the type of the other operand." 4152 if ((LHSTy->isAnyPointerType() || LHSTy->isBlockPointerType()) && 4153 RHS->isNullPointerConstant(Context, Expr::NPC_ValueDependentIsNull)) { 4154 // promote the null to a pointer. 4155 ImpCastExprToType(RHS, LHSTy, CastExpr::CK_Unknown); 4156 return LHSTy; 4157 } 4158 if ((RHSTy->isAnyPointerType() || RHSTy->isBlockPointerType()) && 4159 LHS->isNullPointerConstant(Context, Expr::NPC_ValueDependentIsNull)) { 4160 ImpCastExprToType(LHS, RHSTy, CastExpr::CK_Unknown); 4161 return RHSTy; 4162 } 4163 4164 // All objective-c pointer type analysis is done here. 4165 QualType compositeType = FindCompositeObjCPointerType(LHS, RHS, 4166 QuestionLoc); 4167 if (!compositeType.isNull()) 4168 return compositeType; 4169 4170 4171 // Handle block pointer types. 4172 if (LHSTy->isBlockPointerType() || RHSTy->isBlockPointerType()) { 4173 if (!LHSTy->isBlockPointerType() || !RHSTy->isBlockPointerType()) { 4174 if (LHSTy->isVoidPointerType() || RHSTy->isVoidPointerType()) { 4175 QualType destType = Context.getPointerType(Context.VoidTy); 4176 ImpCastExprToType(LHS, destType, CastExpr::CK_BitCast); 4177 ImpCastExprToType(RHS, destType, CastExpr::CK_BitCast); 4178 return destType; 4179 } 4180 Diag(QuestionLoc, diag::err_typecheck_cond_incompatible_operands) 4181 << LHSTy << RHSTy << LHS->getSourceRange() << RHS->getSourceRange(); 4182 return QualType(); 4183 } 4184 // We have 2 block pointer types. 4185 if (Context.getCanonicalType(LHSTy) == Context.getCanonicalType(RHSTy)) { 4186 // Two identical block pointer types are always compatible. 4187 return LHSTy; 4188 } 4189 // The block pointer types aren't identical, continue checking. 4190 QualType lhptee = LHSTy->getAs<BlockPointerType>()->getPointeeType(); 4191 QualType rhptee = RHSTy->getAs<BlockPointerType>()->getPointeeType(); 4192 4193 if (!Context.typesAreCompatible(lhptee.getUnqualifiedType(), 4194 rhptee.getUnqualifiedType())) { 4195 Diag(QuestionLoc, diag::warn_typecheck_cond_incompatible_pointers) 4196 << LHSTy << RHSTy << LHS->getSourceRange() << RHS->getSourceRange(); 4197 // In this situation, we assume void* type. No especially good 4198 // reason, but this is what gcc does, and we do have to pick 4199 // to get a consistent AST. 4200 QualType incompatTy = Context.getPointerType(Context.VoidTy); 4201 ImpCastExprToType(LHS, incompatTy, CastExpr::CK_BitCast); 4202 ImpCastExprToType(RHS, incompatTy, CastExpr::CK_BitCast); 4203 return incompatTy; 4204 } 4205 // The block pointer types are compatible. 4206 ImpCastExprToType(LHS, LHSTy, CastExpr::CK_BitCast); 4207 ImpCastExprToType(RHS, LHSTy, CastExpr::CK_BitCast); 4208 return LHSTy; 4209 } 4210 4211 // Check constraints for C object pointers types (C99 6.5.15p3,6). 4212 if (LHSTy->isPointerType() && RHSTy->isPointerType()) { 4213 // get the "pointed to" types 4214 QualType lhptee = LHSTy->getAs<PointerType>()->getPointeeType(); 4215 QualType rhptee = RHSTy->getAs<PointerType>()->getPointeeType(); 4216 4217 // ignore qualifiers on void (C99 6.5.15p3, clause 6) 4218 if (lhptee->isVoidType() && rhptee->isIncompleteOrObjectType()) { 4219 // Figure out necessary qualifiers (C99 6.5.15p6) 4220 QualType destPointee 4221 = Context.getQualifiedType(lhptee, rhptee.getQualifiers()); 4222 QualType destType = Context.getPointerType(destPointee); 4223 // Add qualifiers if necessary. 4224 ImpCastExprToType(LHS, destType, CastExpr::CK_NoOp); 4225 // Promote to void*. 4226 ImpCastExprToType(RHS, destType, CastExpr::CK_BitCast); 4227 return destType; 4228 } 4229 if (rhptee->isVoidType() && lhptee->isIncompleteOrObjectType()) { 4230 QualType destPointee 4231 = Context.getQualifiedType(rhptee, lhptee.getQualifiers()); 4232 QualType destType = Context.getPointerType(destPointee); 4233 // Add qualifiers if necessary. 4234 ImpCastExprToType(RHS, destType, CastExpr::CK_NoOp); 4235 // Promote to void*. 4236 ImpCastExprToType(LHS, destType, CastExpr::CK_BitCast); 4237 return destType; 4238 } 4239 4240 if (Context.getCanonicalType(LHSTy) == Context.getCanonicalType(RHSTy)) { 4241 // Two identical pointer types are always compatible. 4242 return LHSTy; 4243 } 4244 if (!Context.typesAreCompatible(lhptee.getUnqualifiedType(), 4245 rhptee.getUnqualifiedType())) { 4246 Diag(QuestionLoc, diag::warn_typecheck_cond_incompatible_pointers) 4247 << LHSTy << RHSTy << LHS->getSourceRange() << RHS->getSourceRange(); 4248 // In this situation, we assume void* type. No especially good 4249 // reason, but this is what gcc does, and we do have to pick 4250 // to get a consistent AST. 4251 QualType incompatTy = Context.getPointerType(Context.VoidTy); 4252 ImpCastExprToType(LHS, incompatTy, CastExpr::CK_BitCast); 4253 ImpCastExprToType(RHS, incompatTy, CastExpr::CK_BitCast); 4254 return incompatTy; 4255 } 4256 // The pointer types are compatible. 4257 // C99 6.5.15p6: If both operands are pointers to compatible types *or* to 4258 // differently qualified versions of compatible types, the result type is 4259 // a pointer to an appropriately qualified version of the *composite* 4260 // type. 4261 // FIXME: Need to calculate the composite type. 4262 // FIXME: Need to add qualifiers 4263 ImpCastExprToType(LHS, LHSTy, CastExpr::CK_BitCast); 4264 ImpCastExprToType(RHS, LHSTy, CastExpr::CK_BitCast); 4265 return LHSTy; 4266 } 4267 4268 // GCC compatibility: soften pointer/integer mismatch. 4269 if (RHSTy->isPointerType() && LHSTy->isIntegerType()) { 4270 Diag(QuestionLoc, diag::warn_typecheck_cond_pointer_integer_mismatch) 4271 << LHSTy << RHSTy << LHS->getSourceRange() << RHS->getSourceRange(); 4272 ImpCastExprToType(LHS, RHSTy, CastExpr::CK_IntegralToPointer); 4273 return RHSTy; 4274 } 4275 if (LHSTy->isPointerType() && RHSTy->isIntegerType()) { 4276 Diag(QuestionLoc, diag::warn_typecheck_cond_pointer_integer_mismatch) 4277 << LHSTy << RHSTy << LHS->getSourceRange() << RHS->getSourceRange(); 4278 ImpCastExprToType(RHS, LHSTy, CastExpr::CK_IntegralToPointer); 4279 return LHSTy; 4280 } 4281 4282 // Otherwise, the operands are not compatible. 4283 Diag(QuestionLoc, diag::err_typecheck_cond_incompatible_operands) 4284 << LHSTy << RHSTy << LHS->getSourceRange() << RHS->getSourceRange(); 4285 return QualType(); 4286} 4287 4288/// FindCompositeObjCPointerType - Helper method to find composite type of 4289/// two objective-c pointer types of the two input expressions. 4290QualType Sema::FindCompositeObjCPointerType(Expr *&LHS, Expr *&RHS, 4291 SourceLocation QuestionLoc) { 4292 QualType LHSTy = LHS->getType(); 4293 QualType RHSTy = RHS->getType(); 4294 4295 // Handle things like Class and struct objc_class*. Here we case the result 4296 // to the pseudo-builtin, because that will be implicitly cast back to the 4297 // redefinition type if an attempt is made to access its fields. 4298 if (LHSTy->isObjCClassType() && 4299 (RHSTy.getDesugaredType() == Context.ObjCClassRedefinitionType)) { 4300 ImpCastExprToType(RHS, LHSTy, CastExpr::CK_BitCast); 4301 return LHSTy; 4302 } 4303 if (RHSTy->isObjCClassType() && 4304 (LHSTy.getDesugaredType() == Context.ObjCClassRedefinitionType)) { 4305 ImpCastExprToType(LHS, RHSTy, CastExpr::CK_BitCast); 4306 return RHSTy; 4307 } 4308 // And the same for struct objc_object* / id 4309 if (LHSTy->isObjCIdType() && 4310 (RHSTy.getDesugaredType() == Context.ObjCIdRedefinitionType)) { 4311 ImpCastExprToType(RHS, LHSTy, CastExpr::CK_BitCast); 4312 return LHSTy; 4313 } 4314 if (RHSTy->isObjCIdType() && 4315 (LHSTy.getDesugaredType() == Context.ObjCIdRedefinitionType)) { 4316 ImpCastExprToType(LHS, RHSTy, CastExpr::CK_BitCast); 4317 return RHSTy; 4318 } 4319 // And the same for struct objc_selector* / SEL 4320 if (Context.isObjCSelType(LHSTy) && 4321 (RHSTy.getDesugaredType() == Context.ObjCSelRedefinitionType)) { 4322 ImpCastExprToType(RHS, LHSTy, CastExpr::CK_BitCast); 4323 return LHSTy; 4324 } 4325 if (Context.isObjCSelType(RHSTy) && 4326 (LHSTy.getDesugaredType() == Context.ObjCSelRedefinitionType)) { 4327 ImpCastExprToType(LHS, RHSTy, CastExpr::CK_BitCast); 4328 return RHSTy; 4329 } 4330 // Check constraints for Objective-C object pointers types. 4331 if (LHSTy->isObjCObjectPointerType() && RHSTy->isObjCObjectPointerType()) { 4332 4333 if (Context.getCanonicalType(LHSTy) == Context.getCanonicalType(RHSTy)) { 4334 // Two identical object pointer types are always compatible. 4335 return LHSTy; 4336 } 4337 const ObjCObjectPointerType *LHSOPT = LHSTy->getAs<ObjCObjectPointerType>(); 4338 const ObjCObjectPointerType *RHSOPT = RHSTy->getAs<ObjCObjectPointerType>(); 4339 QualType compositeType = LHSTy; 4340 4341 // If both operands are interfaces and either operand can be 4342 // assigned to the other, use that type as the composite 4343 // type. This allows 4344 // xxx ? (A*) a : (B*) b 4345 // where B is a subclass of A. 4346 // 4347 // Additionally, as for assignment, if either type is 'id' 4348 // allow silent coercion. Finally, if the types are 4349 // incompatible then make sure to use 'id' as the composite 4350 // type so the result is acceptable for sending messages to. 4351 4352 // FIXME: Consider unifying with 'areComparableObjCPointerTypes'. 4353 // It could return the composite type. 4354 if (Context.canAssignObjCInterfaces(LHSOPT, RHSOPT)) { 4355 compositeType = RHSOPT->isObjCBuiltinType() ? RHSTy : LHSTy; 4356 } else if (Context.canAssignObjCInterfaces(RHSOPT, LHSOPT)) { 4357 compositeType = LHSOPT->isObjCBuiltinType() ? LHSTy : RHSTy; 4358 } else if ((LHSTy->isObjCQualifiedIdType() || 4359 RHSTy->isObjCQualifiedIdType()) && 4360 Context.ObjCQualifiedIdTypesAreCompatible(LHSTy, RHSTy, true)) { 4361 // Need to handle "id<xx>" explicitly. 4362 // GCC allows qualified id and any Objective-C type to devolve to 4363 // id. Currently localizing to here until clear this should be 4364 // part of ObjCQualifiedIdTypesAreCompatible. 4365 compositeType = Context.getObjCIdType(); 4366 } else if (LHSTy->isObjCIdType() || RHSTy->isObjCIdType()) { 4367 compositeType = Context.getObjCIdType(); 4368 } else if (!(compositeType = 4369 Context.areCommonBaseCompatible(LHSOPT, RHSOPT)).isNull()) 4370 ; 4371 else { 4372 Diag(QuestionLoc, diag::ext_typecheck_cond_incompatible_operands) 4373 << LHSTy << RHSTy 4374 << LHS->getSourceRange() << RHS->getSourceRange(); 4375 QualType incompatTy = Context.getObjCIdType(); 4376 ImpCastExprToType(LHS, incompatTy, CastExpr::CK_BitCast); 4377 ImpCastExprToType(RHS, incompatTy, CastExpr::CK_BitCast); 4378 return incompatTy; 4379 } 4380 // The object pointer types are compatible. 4381 ImpCastExprToType(LHS, compositeType, CastExpr::CK_BitCast); 4382 ImpCastExprToType(RHS, compositeType, CastExpr::CK_BitCast); 4383 return compositeType; 4384 } 4385 // Check Objective-C object pointer types and 'void *' 4386 if (LHSTy->isVoidPointerType() && RHSTy->isObjCObjectPointerType()) { 4387 QualType lhptee = LHSTy->getAs<PointerType>()->getPointeeType(); 4388 QualType rhptee = RHSTy->getAs<ObjCObjectPointerType>()->getPointeeType(); 4389 QualType destPointee 4390 = Context.getQualifiedType(lhptee, rhptee.getQualifiers()); 4391 QualType destType = Context.getPointerType(destPointee); 4392 // Add qualifiers if necessary. 4393 ImpCastExprToType(LHS, destType, CastExpr::CK_NoOp); 4394 // Promote to void*. 4395 ImpCastExprToType(RHS, destType, CastExpr::CK_BitCast); 4396 return destType; 4397 } 4398 if (LHSTy->isObjCObjectPointerType() && RHSTy->isVoidPointerType()) { 4399 QualType lhptee = LHSTy->getAs<ObjCObjectPointerType>()->getPointeeType(); 4400 QualType rhptee = RHSTy->getAs<PointerType>()->getPointeeType(); 4401 QualType destPointee 4402 = Context.getQualifiedType(rhptee, lhptee.getQualifiers()); 4403 QualType destType = Context.getPointerType(destPointee); 4404 // Add qualifiers if necessary. 4405 ImpCastExprToType(RHS, destType, CastExpr::CK_NoOp); 4406 // Promote to void*. 4407 ImpCastExprToType(LHS, destType, CastExpr::CK_BitCast); 4408 return destType; 4409 } 4410 return QualType(); 4411} 4412 4413/// ActOnConditionalOp - Parse a ?: operation. Note that 'LHS' may be null 4414/// in the case of a the GNU conditional expr extension. 4415Action::OwningExprResult Sema::ActOnConditionalOp(SourceLocation QuestionLoc, 4416 SourceLocation ColonLoc, 4417 ExprArg Cond, ExprArg LHS, 4418 ExprArg RHS) { 4419 Expr *CondExpr = (Expr *) Cond.get(); 4420 Expr *LHSExpr = (Expr *) LHS.get(), *RHSExpr = (Expr *) RHS.get(); 4421 4422 // If this is the gnu "x ?: y" extension, analyze the types as though the LHS 4423 // was the condition. 4424 bool isLHSNull = LHSExpr == 0; 4425 if (isLHSNull) 4426 LHSExpr = CondExpr; 4427 4428 QualType result = CheckConditionalOperands(CondExpr, LHSExpr, 4429 RHSExpr, QuestionLoc); 4430 if (result.isNull()) 4431 return ExprError(); 4432 4433 Cond.release(); 4434 LHS.release(); 4435 RHS.release(); 4436 return Owned(new (Context) ConditionalOperator(CondExpr, QuestionLoc, 4437 isLHSNull ? 0 : LHSExpr, 4438 ColonLoc, RHSExpr, result)); 4439} 4440 4441// CheckPointerTypesForAssignment - This is a very tricky routine (despite 4442// being closely modeled after the C99 spec:-). The odd characteristic of this 4443// routine is it effectively iqnores the qualifiers on the top level pointee. 4444// This circumvents the usual type rules specified in 6.2.7p1 & 6.7.5.[1-3]. 4445// FIXME: add a couple examples in this comment. 4446Sema::AssignConvertType 4447Sema::CheckPointerTypesForAssignment(QualType lhsType, QualType rhsType) { 4448 QualType lhptee, rhptee; 4449 4450 if ((lhsType->isObjCClassType() && 4451 (rhsType.getDesugaredType() == Context.ObjCClassRedefinitionType)) || 4452 (rhsType->isObjCClassType() && 4453 (lhsType.getDesugaredType() == Context.ObjCClassRedefinitionType))) { 4454 return Compatible; 4455 } 4456 4457 // get the "pointed to" type (ignoring qualifiers at the top level) 4458 lhptee = lhsType->getAs<PointerType>()->getPointeeType(); 4459 rhptee = rhsType->getAs<PointerType>()->getPointeeType(); 4460 4461 // make sure we operate on the canonical type 4462 lhptee = Context.getCanonicalType(lhptee); 4463 rhptee = Context.getCanonicalType(rhptee); 4464 4465 AssignConvertType ConvTy = Compatible; 4466 4467 // C99 6.5.16.1p1: This following citation is common to constraints 4468 // 3 & 4 (below). ...and the type *pointed to* by the left has all the 4469 // qualifiers of the type *pointed to* by the right; 4470 // FIXME: Handle ExtQualType 4471 if (!lhptee.isAtLeastAsQualifiedAs(rhptee)) 4472 ConvTy = CompatiblePointerDiscardsQualifiers; 4473 4474 // C99 6.5.16.1p1 (constraint 4): If one operand is a pointer to an object or 4475 // incomplete type and the other is a pointer to a qualified or unqualified 4476 // version of void... 4477 if (lhptee->isVoidType()) { 4478 if (rhptee->isIncompleteOrObjectType()) 4479 return ConvTy; 4480 4481 // As an extension, we allow cast to/from void* to function pointer. 4482 assert(rhptee->isFunctionType()); 4483 return FunctionVoidPointer; 4484 } 4485 4486 if (rhptee->isVoidType()) { 4487 if (lhptee->isIncompleteOrObjectType()) 4488 return ConvTy; 4489 4490 // As an extension, we allow cast to/from void* to function pointer. 4491 assert(lhptee->isFunctionType()); 4492 return FunctionVoidPointer; 4493 } 4494 // C99 6.5.16.1p1 (constraint 3): both operands are pointers to qualified or 4495 // unqualified versions of compatible types, ... 4496 lhptee = lhptee.getUnqualifiedType(); 4497 rhptee = rhptee.getUnqualifiedType(); 4498 if (!Context.typesAreCompatible(lhptee, rhptee)) { 4499 // Check if the pointee types are compatible ignoring the sign. 4500 // We explicitly check for char so that we catch "char" vs 4501 // "unsigned char" on systems where "char" is unsigned. 4502 if (lhptee->isCharType()) 4503 lhptee = Context.UnsignedCharTy; 4504 else if (lhptee->isSignedIntegerType()) 4505 lhptee = Context.getCorrespondingUnsignedType(lhptee); 4506 4507 if (rhptee->isCharType()) 4508 rhptee = Context.UnsignedCharTy; 4509 else if (rhptee->isSignedIntegerType()) 4510 rhptee = Context.getCorrespondingUnsignedType(rhptee); 4511 4512 if (lhptee == rhptee) { 4513 // Types are compatible ignoring the sign. Qualifier incompatibility 4514 // takes priority over sign incompatibility because the sign 4515 // warning can be disabled. 4516 if (ConvTy != Compatible) 4517 return ConvTy; 4518 return IncompatiblePointerSign; 4519 } 4520 4521 // If we are a multi-level pointer, it's possible that our issue is simply 4522 // one of qualification - e.g. char ** -> const char ** is not allowed. If 4523 // the eventual target type is the same and the pointers have the same 4524 // level of indirection, this must be the issue. 4525 if (lhptee->isPointerType() && rhptee->isPointerType()) { 4526 do { 4527 lhptee = lhptee->getAs<PointerType>()->getPointeeType(); 4528 rhptee = rhptee->getAs<PointerType>()->getPointeeType(); 4529 4530 lhptee = Context.getCanonicalType(lhptee); 4531 rhptee = Context.getCanonicalType(rhptee); 4532 } while (lhptee->isPointerType() && rhptee->isPointerType()); 4533 4534 if (Context.hasSameUnqualifiedType(lhptee, rhptee)) 4535 return IncompatibleNestedPointerQualifiers; 4536 } 4537 4538 // General pointer incompatibility takes priority over qualifiers. 4539 return IncompatiblePointer; 4540 } 4541 return ConvTy; 4542} 4543 4544/// CheckBlockPointerTypesForAssignment - This routine determines whether two 4545/// block pointer types are compatible or whether a block and normal pointer 4546/// are compatible. It is more restrict than comparing two function pointer 4547// types. 4548Sema::AssignConvertType 4549Sema::CheckBlockPointerTypesForAssignment(QualType lhsType, 4550 QualType rhsType) { 4551 QualType lhptee, rhptee; 4552 4553 // get the "pointed to" type (ignoring qualifiers at the top level) 4554 lhptee = lhsType->getAs<BlockPointerType>()->getPointeeType(); 4555 rhptee = rhsType->getAs<BlockPointerType>()->getPointeeType(); 4556 4557 // make sure we operate on the canonical type 4558 lhptee = Context.getCanonicalType(lhptee); 4559 rhptee = Context.getCanonicalType(rhptee); 4560 4561 AssignConvertType ConvTy = Compatible; 4562 4563 // For blocks we enforce that qualifiers are identical. 4564 if (lhptee.getLocalCVRQualifiers() != rhptee.getLocalCVRQualifiers()) 4565 ConvTy = CompatiblePointerDiscardsQualifiers; 4566 4567 if (!getLangOptions().CPlusPlus) { 4568 if (!Context.typesAreBlockPointerCompatible(lhsType, rhsType)) 4569 return IncompatibleBlockPointer; 4570 } 4571 else if (!Context.typesAreCompatible(lhptee, rhptee)) 4572 return IncompatibleBlockPointer; 4573 return ConvTy; 4574} 4575 4576/// CheckObjCPointerTypesForAssignment - Compares two objective-c pointer types 4577/// for assignment compatibility. 4578Sema::AssignConvertType 4579Sema::CheckObjCPointerTypesForAssignment(QualType lhsType, QualType rhsType) { 4580 if (lhsType->isObjCBuiltinType()) { 4581 // Class is not compatible with ObjC object pointers. 4582 if (lhsType->isObjCClassType() && !rhsType->isObjCBuiltinType() && 4583 !rhsType->isObjCQualifiedClassType()) 4584 return IncompatiblePointer; 4585 return Compatible; 4586 } 4587 if (rhsType->isObjCBuiltinType()) { 4588 // Class is not compatible with ObjC object pointers. 4589 if (rhsType->isObjCClassType() && !lhsType->isObjCBuiltinType() && 4590 !lhsType->isObjCQualifiedClassType()) 4591 return IncompatiblePointer; 4592 return Compatible; 4593 } 4594 QualType lhptee = 4595 lhsType->getAs<ObjCObjectPointerType>()->getPointeeType(); 4596 QualType rhptee = 4597 rhsType->getAs<ObjCObjectPointerType>()->getPointeeType(); 4598 // make sure we operate on the canonical type 4599 lhptee = Context.getCanonicalType(lhptee); 4600 rhptee = Context.getCanonicalType(rhptee); 4601 if (!lhptee.isAtLeastAsQualifiedAs(rhptee)) 4602 return CompatiblePointerDiscardsQualifiers; 4603 4604 if (Context.typesAreCompatible(lhsType, rhsType)) 4605 return Compatible; 4606 if (lhsType->isObjCQualifiedIdType() || rhsType->isObjCQualifiedIdType()) 4607 return IncompatibleObjCQualifiedId; 4608 return IncompatiblePointer; 4609} 4610 4611/// CheckAssignmentConstraints (C99 6.5.16) - This routine currently 4612/// has code to accommodate several GCC extensions when type checking 4613/// pointers. Here are some objectionable examples that GCC considers warnings: 4614/// 4615/// int a, *pint; 4616/// short *pshort; 4617/// struct foo *pfoo; 4618/// 4619/// pint = pshort; // warning: assignment from incompatible pointer type 4620/// a = pint; // warning: assignment makes integer from pointer without a cast 4621/// pint = a; // warning: assignment makes pointer from integer without a cast 4622/// pint = pfoo; // warning: assignment from incompatible pointer type 4623/// 4624/// As a result, the code for dealing with pointers is more complex than the 4625/// C99 spec dictates. 4626/// 4627Sema::AssignConvertType 4628Sema::CheckAssignmentConstraints(QualType lhsType, QualType rhsType) { 4629 // Get canonical types. We're not formatting these types, just comparing 4630 // them. 4631 lhsType = Context.getCanonicalType(lhsType).getUnqualifiedType(); 4632 rhsType = Context.getCanonicalType(rhsType).getUnqualifiedType(); 4633 4634 if (lhsType == rhsType) 4635 return Compatible; // Common case: fast path an exact match. 4636 4637 if ((lhsType->isObjCClassType() && 4638 (rhsType.getDesugaredType() == Context.ObjCClassRedefinitionType)) || 4639 (rhsType->isObjCClassType() && 4640 (lhsType.getDesugaredType() == Context.ObjCClassRedefinitionType))) { 4641 return Compatible; 4642 } 4643 4644 // If the left-hand side is a reference type, then we are in a 4645 // (rare!) case where we've allowed the use of references in C, 4646 // e.g., as a parameter type in a built-in function. In this case, 4647 // just make sure that the type referenced is compatible with the 4648 // right-hand side type. The caller is responsible for adjusting 4649 // lhsType so that the resulting expression does not have reference 4650 // type. 4651 if (const ReferenceType *lhsTypeRef = lhsType->getAs<ReferenceType>()) { 4652 if (Context.typesAreCompatible(lhsTypeRef->getPointeeType(), rhsType)) 4653 return Compatible; 4654 return Incompatible; 4655 } 4656 // Allow scalar to ExtVector assignments, and assignments of an ExtVector type 4657 // to the same ExtVector type. 4658 if (lhsType->isExtVectorType()) { 4659 if (rhsType->isExtVectorType()) 4660 return lhsType == rhsType ? Compatible : Incompatible; 4661 if (!rhsType->isVectorType() && rhsType->isArithmeticType()) 4662 return Compatible; 4663 } 4664 4665 if (lhsType->isVectorType() || rhsType->isVectorType()) { 4666 // If we are allowing lax vector conversions, and LHS and RHS are both 4667 // vectors, the total size only needs to be the same. This is a bitcast; 4668 // no bits are changed but the result type is different. 4669 if (getLangOptions().LaxVectorConversions && 4670 lhsType->isVectorType() && rhsType->isVectorType()) { 4671 if (Context.getTypeSize(lhsType) == Context.getTypeSize(rhsType)) 4672 return IncompatibleVectors; 4673 } 4674 return Incompatible; 4675 } 4676 4677 if (lhsType->isArithmeticType() && rhsType->isArithmeticType()) 4678 return Compatible; 4679 4680 if (isa<PointerType>(lhsType)) { 4681 if (rhsType->isIntegerType()) 4682 return IntToPointer; 4683 4684 if (isa<PointerType>(rhsType)) 4685 return CheckPointerTypesForAssignment(lhsType, rhsType); 4686 4687 // In general, C pointers are not compatible with ObjC object pointers. 4688 if (isa<ObjCObjectPointerType>(rhsType)) { 4689 if (lhsType->isVoidPointerType()) // an exception to the rule. 4690 return Compatible; 4691 return IncompatiblePointer; 4692 } 4693 if (rhsType->getAs<BlockPointerType>()) { 4694 if (lhsType->getAs<PointerType>()->getPointeeType()->isVoidType()) 4695 return Compatible; 4696 4697 // Treat block pointers as objects. 4698 if (getLangOptions().ObjC1 && lhsType->isObjCIdType()) 4699 return Compatible; 4700 } 4701 return Incompatible; 4702 } 4703 4704 if (isa<BlockPointerType>(lhsType)) { 4705 if (rhsType->isIntegerType()) 4706 return IntToBlockPointer; 4707 4708 // Treat block pointers as objects. 4709 if (getLangOptions().ObjC1 && rhsType->isObjCIdType()) 4710 return Compatible; 4711 4712 if (rhsType->isBlockPointerType()) 4713 return CheckBlockPointerTypesForAssignment(lhsType, rhsType); 4714 4715 if (const PointerType *RHSPT = rhsType->getAs<PointerType>()) { 4716 if (RHSPT->getPointeeType()->isVoidType()) 4717 return Compatible; 4718 } 4719 return Incompatible; 4720 } 4721 4722 if (isa<ObjCObjectPointerType>(lhsType)) { 4723 if (rhsType->isIntegerType()) 4724 return IntToPointer; 4725 4726 // In general, C pointers are not compatible with ObjC object pointers. 4727 if (isa<PointerType>(rhsType)) { 4728 if (rhsType->isVoidPointerType()) // an exception to the rule. 4729 return Compatible; 4730 return IncompatiblePointer; 4731 } 4732 if (rhsType->isObjCObjectPointerType()) { 4733 return CheckObjCPointerTypesForAssignment(lhsType, rhsType); 4734 } 4735 if (const PointerType *RHSPT = rhsType->getAs<PointerType>()) { 4736 if (RHSPT->getPointeeType()->isVoidType()) 4737 return Compatible; 4738 } 4739 // Treat block pointers as objects. 4740 if (rhsType->isBlockPointerType()) 4741 return Compatible; 4742 return Incompatible; 4743 } 4744 if (isa<PointerType>(rhsType)) { 4745 // C99 6.5.16.1p1: the left operand is _Bool and the right is a pointer. 4746 if (lhsType == Context.BoolTy) 4747 return Compatible; 4748 4749 if (lhsType->isIntegerType()) 4750 return PointerToInt; 4751 4752 if (isa<PointerType>(lhsType)) 4753 return CheckPointerTypesForAssignment(lhsType, rhsType); 4754 4755 if (isa<BlockPointerType>(lhsType) && 4756 rhsType->getAs<PointerType>()->getPointeeType()->isVoidType()) 4757 return Compatible; 4758 return Incompatible; 4759 } 4760 if (isa<ObjCObjectPointerType>(rhsType)) { 4761 // C99 6.5.16.1p1: the left operand is _Bool and the right is a pointer. 4762 if (lhsType == Context.BoolTy) 4763 return Compatible; 4764 4765 if (lhsType->isIntegerType()) 4766 return PointerToInt; 4767 4768 // In general, C pointers are not compatible with ObjC object pointers. 4769 if (isa<PointerType>(lhsType)) { 4770 if (lhsType->isVoidPointerType()) // an exception to the rule. 4771 return Compatible; 4772 return IncompatiblePointer; 4773 } 4774 if (isa<BlockPointerType>(lhsType) && 4775 rhsType->getAs<PointerType>()->getPointeeType()->isVoidType()) 4776 return Compatible; 4777 return Incompatible; 4778 } 4779 4780 if (isa<TagType>(lhsType) && isa<TagType>(rhsType)) { 4781 if (Context.typesAreCompatible(lhsType, rhsType)) 4782 return Compatible; 4783 } 4784 return Incompatible; 4785} 4786 4787/// \brief Constructs a transparent union from an expression that is 4788/// used to initialize the transparent union. 4789static void ConstructTransparentUnion(ASTContext &C, Expr *&E, 4790 QualType UnionType, FieldDecl *Field) { 4791 // Build an initializer list that designates the appropriate member 4792 // of the transparent union. 4793 InitListExpr *Initializer = new (C) InitListExpr(C, SourceLocation(), 4794 &E, 1, 4795 SourceLocation()); 4796 Initializer->setType(UnionType); 4797 Initializer->setInitializedFieldInUnion(Field); 4798 4799 // Build a compound literal constructing a value of the transparent 4800 // union type from this initializer list. 4801 TypeSourceInfo *unionTInfo = C.getTrivialTypeSourceInfo(UnionType); 4802 E = new (C) CompoundLiteralExpr(SourceLocation(), unionTInfo, UnionType, 4803 Initializer, false); 4804} 4805 4806Sema::AssignConvertType 4807Sema::CheckTransparentUnionArgumentConstraints(QualType ArgType, Expr *&rExpr) { 4808 QualType FromType = rExpr->getType(); 4809 4810 // If the ArgType is a Union type, we want to handle a potential 4811 // transparent_union GCC extension. 4812 const RecordType *UT = ArgType->getAsUnionType(); 4813 if (!UT || !UT->getDecl()->hasAttr<TransparentUnionAttr>()) 4814 return Incompatible; 4815 4816 // The field to initialize within the transparent union. 4817 RecordDecl *UD = UT->getDecl(); 4818 FieldDecl *InitField = 0; 4819 // It's compatible if the expression matches any of the fields. 4820 for (RecordDecl::field_iterator it = UD->field_begin(), 4821 itend = UD->field_end(); 4822 it != itend; ++it) { 4823 if (it->getType()->isPointerType()) { 4824 // If the transparent union contains a pointer type, we allow: 4825 // 1) void pointer 4826 // 2) null pointer constant 4827 if (FromType->isPointerType()) 4828 if (FromType->getAs<PointerType>()->getPointeeType()->isVoidType()) { 4829 ImpCastExprToType(rExpr, it->getType(), CastExpr::CK_BitCast); 4830 InitField = *it; 4831 break; 4832 } 4833 4834 if (rExpr->isNullPointerConstant(Context, 4835 Expr::NPC_ValueDependentIsNull)) { 4836 ImpCastExprToType(rExpr, it->getType(), CastExpr::CK_IntegralToPointer); 4837 InitField = *it; 4838 break; 4839 } 4840 } 4841 4842 if (CheckAssignmentConstraints(it->getType(), rExpr->getType()) 4843 == Compatible) { 4844 InitField = *it; 4845 break; 4846 } 4847 } 4848 4849 if (!InitField) 4850 return Incompatible; 4851 4852 ConstructTransparentUnion(Context, rExpr, ArgType, InitField); 4853 return Compatible; 4854} 4855 4856Sema::AssignConvertType 4857Sema::CheckSingleAssignmentConstraints(QualType lhsType, Expr *&rExpr) { 4858 if (getLangOptions().CPlusPlus) { 4859 if (!lhsType->isRecordType()) { 4860 // C++ 5.17p3: If the left operand is not of class type, the 4861 // expression is implicitly converted (C++ 4) to the 4862 // cv-unqualified type of the left operand. 4863 if (PerformImplicitConversion(rExpr, lhsType.getUnqualifiedType(), 4864 AA_Assigning)) 4865 return Incompatible; 4866 return Compatible; 4867 } 4868 4869 // FIXME: Currently, we fall through and treat C++ classes like C 4870 // structures. 4871 } 4872 4873 // C99 6.5.16.1p1: the left operand is a pointer and the right is 4874 // a null pointer constant. 4875 if ((lhsType->isPointerType() || 4876 lhsType->isObjCObjectPointerType() || 4877 lhsType->isBlockPointerType()) 4878 && rExpr->isNullPointerConstant(Context, 4879 Expr::NPC_ValueDependentIsNull)) { 4880 ImpCastExprToType(rExpr, lhsType, CastExpr::CK_Unknown); 4881 return Compatible; 4882 } 4883 4884 // This check seems unnatural, however it is necessary to ensure the proper 4885 // conversion of functions/arrays. If the conversion were done for all 4886 // DeclExpr's (created by ActOnIdExpression), it would mess up the unary 4887 // expressions that surpress this implicit conversion (&, sizeof). 4888 // 4889 // Suppress this for references: C++ 8.5.3p5. 4890 if (!lhsType->isReferenceType()) 4891 DefaultFunctionArrayLvalueConversion(rExpr); 4892 4893 Sema::AssignConvertType result = 4894 CheckAssignmentConstraints(lhsType, rExpr->getType()); 4895 4896 // C99 6.5.16.1p2: The value of the right operand is converted to the 4897 // type of the assignment expression. 4898 // CheckAssignmentConstraints allows the left-hand side to be a reference, 4899 // so that we can use references in built-in functions even in C. 4900 // The getNonReferenceType() call makes sure that the resulting expression 4901 // does not have reference type. 4902 if (result != Incompatible && rExpr->getType() != lhsType) 4903 ImpCastExprToType(rExpr, lhsType.getNonReferenceType(), 4904 CastExpr::CK_Unknown); 4905 return result; 4906} 4907 4908QualType Sema::InvalidOperands(SourceLocation Loc, Expr *&lex, Expr *&rex) { 4909 Diag(Loc, diag::err_typecheck_invalid_operands) 4910 << lex->getType() << rex->getType() 4911 << lex->getSourceRange() << rex->getSourceRange(); 4912 return QualType(); 4913} 4914 4915QualType Sema::CheckVectorOperands(SourceLocation Loc, Expr *&lex, Expr *&rex) { 4916 // For conversion purposes, we ignore any qualifiers. 4917 // For example, "const float" and "float" are equivalent. 4918 QualType lhsType = 4919 Context.getCanonicalType(lex->getType()).getUnqualifiedType(); 4920 QualType rhsType = 4921 Context.getCanonicalType(rex->getType()).getUnqualifiedType(); 4922 4923 // If the vector types are identical, return. 4924 if (lhsType == rhsType) 4925 return lhsType; 4926 4927 // Handle the case of a vector & extvector type of the same size and element 4928 // type. It would be nice if we only had one vector type someday. 4929 if (getLangOptions().LaxVectorConversions) { 4930 // FIXME: Should we warn here? 4931 if (const VectorType *LV = lhsType->getAs<VectorType>()) { 4932 if (const VectorType *RV = rhsType->getAs<VectorType>()) 4933 if (LV->getElementType() == RV->getElementType() && 4934 LV->getNumElements() == RV->getNumElements()) { 4935 if (lhsType->isExtVectorType()) { 4936 ImpCastExprToType(rex, lhsType, CastExpr::CK_BitCast); 4937 return lhsType; 4938 } 4939 4940 ImpCastExprToType(lex, rhsType, CastExpr::CK_BitCast); 4941 return rhsType; 4942 } 4943 } 4944 } 4945 4946 // Canonicalize the ExtVector to the LHS, remember if we swapped so we can 4947 // swap back (so that we don't reverse the inputs to a subtract, for instance. 4948 bool swapped = false; 4949 if (rhsType->isExtVectorType()) { 4950 swapped = true; 4951 std::swap(rex, lex); 4952 std::swap(rhsType, lhsType); 4953 } 4954 4955 // Handle the case of an ext vector and scalar. 4956 if (const ExtVectorType *LV = lhsType->getAs<ExtVectorType>()) { 4957 QualType EltTy = LV->getElementType(); 4958 if (EltTy->isIntegralType() && rhsType->isIntegralType()) { 4959 if (Context.getIntegerTypeOrder(EltTy, rhsType) >= 0) { 4960 ImpCastExprToType(rex, lhsType, CastExpr::CK_IntegralCast); 4961 if (swapped) std::swap(rex, lex); 4962 return lhsType; 4963 } 4964 } 4965 if (EltTy->isRealFloatingType() && rhsType->isScalarType() && 4966 rhsType->isRealFloatingType()) { 4967 if (Context.getFloatingTypeOrder(EltTy, rhsType) >= 0) { 4968 ImpCastExprToType(rex, lhsType, CastExpr::CK_FloatingCast); 4969 if (swapped) std::swap(rex, lex); 4970 return lhsType; 4971 } 4972 } 4973 } 4974 4975 // Vectors of different size or scalar and non-ext-vector are errors. 4976 Diag(Loc, diag::err_typecheck_vector_not_convertable) 4977 << lex->getType() << rex->getType() 4978 << lex->getSourceRange() << rex->getSourceRange(); 4979 return QualType(); 4980} 4981 4982QualType Sema::CheckMultiplyDivideOperands( 4983 Expr *&lex, Expr *&rex, SourceLocation Loc, bool isCompAssign, bool isDiv) { 4984 if (lex->getType()->isVectorType() || rex->getType()->isVectorType()) 4985 return CheckVectorOperands(Loc, lex, rex); 4986 4987 QualType compType = UsualArithmeticConversions(lex, rex, isCompAssign); 4988 4989 if (!lex->getType()->isArithmeticType() || 4990 !rex->getType()->isArithmeticType()) 4991 return InvalidOperands(Loc, lex, rex); 4992 4993 // Check for division by zero. 4994 if (isDiv && 4995 rex->isNullPointerConstant(Context, Expr::NPC_ValueDependentIsNotNull)) 4996 DiagRuntimeBehavior(Loc, PDiag(diag::warn_division_by_zero) 4997 << rex->getSourceRange()); 4998 4999 return compType; 5000} 5001 5002QualType Sema::CheckRemainderOperands( 5003 Expr *&lex, Expr *&rex, SourceLocation Loc, bool isCompAssign) { 5004 if (lex->getType()->isVectorType() || rex->getType()->isVectorType()) { 5005 if (lex->getType()->isIntegerType() && rex->getType()->isIntegerType()) 5006 return CheckVectorOperands(Loc, lex, rex); 5007 return InvalidOperands(Loc, lex, rex); 5008 } 5009 5010 QualType compType = UsualArithmeticConversions(lex, rex, isCompAssign); 5011 5012 if (!lex->getType()->isIntegerType() || !rex->getType()->isIntegerType()) 5013 return InvalidOperands(Loc, lex, rex); 5014 5015 // Check for remainder by zero. 5016 if (rex->isNullPointerConstant(Context, Expr::NPC_ValueDependentIsNotNull)) 5017 DiagRuntimeBehavior(Loc, PDiag(diag::warn_remainder_by_zero) 5018 << rex->getSourceRange()); 5019 5020 return compType; 5021} 5022 5023QualType Sema::CheckAdditionOperands( // C99 6.5.6 5024 Expr *&lex, Expr *&rex, SourceLocation Loc, QualType* CompLHSTy) { 5025 if (lex->getType()->isVectorType() || rex->getType()->isVectorType()) { 5026 QualType compType = CheckVectorOperands(Loc, lex, rex); 5027 if (CompLHSTy) *CompLHSTy = compType; 5028 return compType; 5029 } 5030 5031 QualType compType = UsualArithmeticConversions(lex, rex, CompLHSTy); 5032 5033 // handle the common case first (both operands are arithmetic). 5034 if (lex->getType()->isArithmeticType() && 5035 rex->getType()->isArithmeticType()) { 5036 if (CompLHSTy) *CompLHSTy = compType; 5037 return compType; 5038 } 5039 5040 // Put any potential pointer into PExp 5041 Expr* PExp = lex, *IExp = rex; 5042 if (IExp->getType()->isAnyPointerType()) 5043 std::swap(PExp, IExp); 5044 5045 if (PExp->getType()->isAnyPointerType()) { 5046 5047 if (IExp->getType()->isIntegerType()) { 5048 QualType PointeeTy = PExp->getType()->getPointeeType(); 5049 5050 // Check for arithmetic on pointers to incomplete types. 5051 if (PointeeTy->isVoidType()) { 5052 if (getLangOptions().CPlusPlus) { 5053 Diag(Loc, diag::err_typecheck_pointer_arith_void_type) 5054 << lex->getSourceRange() << rex->getSourceRange(); 5055 return QualType(); 5056 } 5057 5058 // GNU extension: arithmetic on pointer to void 5059 Diag(Loc, diag::ext_gnu_void_ptr) 5060 << lex->getSourceRange() << rex->getSourceRange(); 5061 } else if (PointeeTy->isFunctionType()) { 5062 if (getLangOptions().CPlusPlus) { 5063 Diag(Loc, diag::err_typecheck_pointer_arith_function_type) 5064 << lex->getType() << lex->getSourceRange(); 5065 return QualType(); 5066 } 5067 5068 // GNU extension: arithmetic on pointer to function 5069 Diag(Loc, diag::ext_gnu_ptr_func_arith) 5070 << lex->getType() << lex->getSourceRange(); 5071 } else { 5072 // Check if we require a complete type. 5073 if (((PExp->getType()->isPointerType() && 5074 !PExp->getType()->isDependentType()) || 5075 PExp->getType()->isObjCObjectPointerType()) && 5076 RequireCompleteType(Loc, PointeeTy, 5077 PDiag(diag::err_typecheck_arithmetic_incomplete_type) 5078 << PExp->getSourceRange() 5079 << PExp->getType())) 5080 return QualType(); 5081 } 5082 // Diagnose bad cases where we step over interface counts. 5083 if (PointeeTy->isObjCObjectType() && LangOpts.ObjCNonFragileABI) { 5084 Diag(Loc, diag::err_arithmetic_nonfragile_interface) 5085 << PointeeTy << PExp->getSourceRange(); 5086 return QualType(); 5087 } 5088 5089 if (CompLHSTy) { 5090 QualType LHSTy = Context.isPromotableBitField(lex); 5091 if (LHSTy.isNull()) { 5092 LHSTy = lex->getType(); 5093 if (LHSTy->isPromotableIntegerType()) 5094 LHSTy = Context.getPromotedIntegerType(LHSTy); 5095 } 5096 *CompLHSTy = LHSTy; 5097 } 5098 return PExp->getType(); 5099 } 5100 } 5101 5102 return InvalidOperands(Loc, lex, rex); 5103} 5104 5105// C99 6.5.6 5106QualType Sema::CheckSubtractionOperands(Expr *&lex, Expr *&rex, 5107 SourceLocation Loc, QualType* CompLHSTy) { 5108 if (lex->getType()->isVectorType() || rex->getType()->isVectorType()) { 5109 QualType compType = CheckVectorOperands(Loc, lex, rex); 5110 if (CompLHSTy) *CompLHSTy = compType; 5111 return compType; 5112 } 5113 5114 QualType compType = UsualArithmeticConversions(lex, rex, CompLHSTy); 5115 5116 // Enforce type constraints: C99 6.5.6p3. 5117 5118 // Handle the common case first (both operands are arithmetic). 5119 if (lex->getType()->isArithmeticType() 5120 && rex->getType()->isArithmeticType()) { 5121 if (CompLHSTy) *CompLHSTy = compType; 5122 return compType; 5123 } 5124 5125 // Either ptr - int or ptr - ptr. 5126 if (lex->getType()->isAnyPointerType()) { 5127 QualType lpointee = lex->getType()->getPointeeType(); 5128 5129 // The LHS must be an completely-defined object type. 5130 5131 bool ComplainAboutVoid = false; 5132 Expr *ComplainAboutFunc = 0; 5133 if (lpointee->isVoidType()) { 5134 if (getLangOptions().CPlusPlus) { 5135 Diag(Loc, diag::err_typecheck_pointer_arith_void_type) 5136 << lex->getSourceRange() << rex->getSourceRange(); 5137 return QualType(); 5138 } 5139 5140 // GNU C extension: arithmetic on pointer to void 5141 ComplainAboutVoid = true; 5142 } else if (lpointee->isFunctionType()) { 5143 if (getLangOptions().CPlusPlus) { 5144 Diag(Loc, diag::err_typecheck_pointer_arith_function_type) 5145 << lex->getType() << lex->getSourceRange(); 5146 return QualType(); 5147 } 5148 5149 // GNU C extension: arithmetic on pointer to function 5150 ComplainAboutFunc = lex; 5151 } else if (!lpointee->isDependentType() && 5152 RequireCompleteType(Loc, lpointee, 5153 PDiag(diag::err_typecheck_sub_ptr_object) 5154 << lex->getSourceRange() 5155 << lex->getType())) 5156 return QualType(); 5157 5158 // Diagnose bad cases where we step over interface counts. 5159 if (lpointee->isObjCObjectType() && LangOpts.ObjCNonFragileABI) { 5160 Diag(Loc, diag::err_arithmetic_nonfragile_interface) 5161 << lpointee << lex->getSourceRange(); 5162 return QualType(); 5163 } 5164 5165 // The result type of a pointer-int computation is the pointer type. 5166 if (rex->getType()->isIntegerType()) { 5167 if (ComplainAboutVoid) 5168 Diag(Loc, diag::ext_gnu_void_ptr) 5169 << lex->getSourceRange() << rex->getSourceRange(); 5170 if (ComplainAboutFunc) 5171 Diag(Loc, diag::ext_gnu_ptr_func_arith) 5172 << ComplainAboutFunc->getType() 5173 << ComplainAboutFunc->getSourceRange(); 5174 5175 if (CompLHSTy) *CompLHSTy = lex->getType(); 5176 return lex->getType(); 5177 } 5178 5179 // Handle pointer-pointer subtractions. 5180 if (const PointerType *RHSPTy = rex->getType()->getAs<PointerType>()) { 5181 QualType rpointee = RHSPTy->getPointeeType(); 5182 5183 // RHS must be a completely-type object type. 5184 // Handle the GNU void* extension. 5185 if (rpointee->isVoidType()) { 5186 if (getLangOptions().CPlusPlus) { 5187 Diag(Loc, diag::err_typecheck_pointer_arith_void_type) 5188 << lex->getSourceRange() << rex->getSourceRange(); 5189 return QualType(); 5190 } 5191 5192 ComplainAboutVoid = true; 5193 } else if (rpointee->isFunctionType()) { 5194 if (getLangOptions().CPlusPlus) { 5195 Diag(Loc, diag::err_typecheck_pointer_arith_function_type) 5196 << rex->getType() << rex->getSourceRange(); 5197 return QualType(); 5198 } 5199 5200 // GNU extension: arithmetic on pointer to function 5201 if (!ComplainAboutFunc) 5202 ComplainAboutFunc = rex; 5203 } else if (!rpointee->isDependentType() && 5204 RequireCompleteType(Loc, rpointee, 5205 PDiag(diag::err_typecheck_sub_ptr_object) 5206 << rex->getSourceRange() 5207 << rex->getType())) 5208 return QualType(); 5209 5210 if (getLangOptions().CPlusPlus) { 5211 // Pointee types must be the same: C++ [expr.add] 5212 if (!Context.hasSameUnqualifiedType(lpointee, rpointee)) { 5213 Diag(Loc, diag::err_typecheck_sub_ptr_compatible) 5214 << lex->getType() << rex->getType() 5215 << lex->getSourceRange() << rex->getSourceRange(); 5216 return QualType(); 5217 } 5218 } else { 5219 // Pointee types must be compatible C99 6.5.6p3 5220 if (!Context.typesAreCompatible( 5221 Context.getCanonicalType(lpointee).getUnqualifiedType(), 5222 Context.getCanonicalType(rpointee).getUnqualifiedType())) { 5223 Diag(Loc, diag::err_typecheck_sub_ptr_compatible) 5224 << lex->getType() << rex->getType() 5225 << lex->getSourceRange() << rex->getSourceRange(); 5226 return QualType(); 5227 } 5228 } 5229 5230 if (ComplainAboutVoid) 5231 Diag(Loc, diag::ext_gnu_void_ptr) 5232 << lex->getSourceRange() << rex->getSourceRange(); 5233 if (ComplainAboutFunc) 5234 Diag(Loc, diag::ext_gnu_ptr_func_arith) 5235 << ComplainAboutFunc->getType() 5236 << ComplainAboutFunc->getSourceRange(); 5237 5238 if (CompLHSTy) *CompLHSTy = lex->getType(); 5239 return Context.getPointerDiffType(); 5240 } 5241 } 5242 5243 return InvalidOperands(Loc, lex, rex); 5244} 5245 5246// C99 6.5.7 5247QualType Sema::CheckShiftOperands(Expr *&lex, Expr *&rex, SourceLocation Loc, 5248 bool isCompAssign) { 5249 // C99 6.5.7p2: Each of the operands shall have integer type. 5250 if (!lex->getType()->isIntegerType() || !rex->getType()->isIntegerType()) 5251 return InvalidOperands(Loc, lex, rex); 5252 5253 // Vector shifts promote their scalar inputs to vector type. 5254 if (lex->getType()->isVectorType() || rex->getType()->isVectorType()) 5255 return CheckVectorOperands(Loc, lex, rex); 5256 5257 // Shifts don't perform usual arithmetic conversions, they just do integer 5258 // promotions on each operand. C99 6.5.7p3 5259 QualType LHSTy = Context.isPromotableBitField(lex); 5260 if (LHSTy.isNull()) { 5261 LHSTy = lex->getType(); 5262 if (LHSTy->isPromotableIntegerType()) 5263 LHSTy = Context.getPromotedIntegerType(LHSTy); 5264 } 5265 if (!isCompAssign) 5266 ImpCastExprToType(lex, LHSTy, CastExpr::CK_IntegralCast); 5267 5268 UsualUnaryConversions(rex); 5269 5270 // Sanity-check shift operands 5271 llvm::APSInt Right; 5272 // Check right/shifter operand 5273 if (!rex->isValueDependent() && 5274 rex->isIntegerConstantExpr(Right, Context)) { 5275 if (Right.isNegative()) 5276 Diag(Loc, diag::warn_shift_negative) << rex->getSourceRange(); 5277 else { 5278 llvm::APInt LeftBits(Right.getBitWidth(), 5279 Context.getTypeSize(lex->getType())); 5280 if (Right.uge(LeftBits)) 5281 Diag(Loc, diag::warn_shift_gt_typewidth) << rex->getSourceRange(); 5282 } 5283 } 5284 5285 // "The type of the result is that of the promoted left operand." 5286 return LHSTy; 5287} 5288 5289// C99 6.5.8, C++ [expr.rel] 5290QualType Sema::CheckCompareOperands(Expr *&lex, Expr *&rex, SourceLocation Loc, 5291 unsigned OpaqueOpc, bool isRelational) { 5292 BinaryOperator::Opcode Opc = (BinaryOperator::Opcode)OpaqueOpc; 5293 5294 // Handle vector comparisons separately. 5295 if (lex->getType()->isVectorType() || rex->getType()->isVectorType()) 5296 return CheckVectorCompareOperands(lex, rex, Loc, isRelational); 5297 5298 // C99 6.5.8p3 / C99 6.5.9p4 5299 if (lex->getType()->isArithmeticType() && rex->getType()->isArithmeticType()) 5300 UsualArithmeticConversions(lex, rex); 5301 else { 5302 UsualUnaryConversions(lex); 5303 UsualUnaryConversions(rex); 5304 } 5305 QualType lType = lex->getType(); 5306 QualType rType = rex->getType(); 5307 5308 if (!lType->isFloatingType() 5309 && !(lType->isBlockPointerType() && isRelational)) { 5310 // For non-floating point types, check for self-comparisons of the form 5311 // x == x, x != x, x < x, etc. These always evaluate to a constant, and 5312 // often indicate logic errors in the program. 5313 // NOTE: Don't warn about comparisons of enum constants. These can arise 5314 // from macro expansions, and are usually quite deliberate. 5315 Expr *LHSStripped = lex->IgnoreParens(); 5316 Expr *RHSStripped = rex->IgnoreParens(); 5317 if (DeclRefExpr* DRL = dyn_cast<DeclRefExpr>(LHSStripped)) 5318 if (DeclRefExpr* DRR = dyn_cast<DeclRefExpr>(RHSStripped)) 5319 if (DRL->getDecl() == DRR->getDecl() && 5320 !isa<EnumConstantDecl>(DRL->getDecl())) 5321 DiagRuntimeBehavior(Loc, PDiag(diag::warn_selfcomparison)); 5322 5323 if (isa<CastExpr>(LHSStripped)) 5324 LHSStripped = LHSStripped->IgnoreParenCasts(); 5325 if (isa<CastExpr>(RHSStripped)) 5326 RHSStripped = RHSStripped->IgnoreParenCasts(); 5327 5328 // Warn about comparisons against a string constant (unless the other 5329 // operand is null), the user probably wants strcmp. 5330 Expr *literalString = 0; 5331 Expr *literalStringStripped = 0; 5332 if ((isa<StringLiteral>(LHSStripped) || isa<ObjCEncodeExpr>(LHSStripped)) && 5333 !RHSStripped->isNullPointerConstant(Context, 5334 Expr::NPC_ValueDependentIsNull)) { 5335 literalString = lex; 5336 literalStringStripped = LHSStripped; 5337 } else if ((isa<StringLiteral>(RHSStripped) || 5338 isa<ObjCEncodeExpr>(RHSStripped)) && 5339 !LHSStripped->isNullPointerConstant(Context, 5340 Expr::NPC_ValueDependentIsNull)) { 5341 literalString = rex; 5342 literalStringStripped = RHSStripped; 5343 } 5344 5345 if (literalString) { 5346 std::string resultComparison; 5347 switch (Opc) { 5348 case BinaryOperator::LT: resultComparison = ") < 0"; break; 5349 case BinaryOperator::GT: resultComparison = ") > 0"; break; 5350 case BinaryOperator::LE: resultComparison = ") <= 0"; break; 5351 case BinaryOperator::GE: resultComparison = ") >= 0"; break; 5352 case BinaryOperator::EQ: resultComparison = ") == 0"; break; 5353 case BinaryOperator::NE: resultComparison = ") != 0"; break; 5354 default: assert(false && "Invalid comparison operator"); 5355 } 5356 5357 DiagRuntimeBehavior(Loc, 5358 PDiag(diag::warn_stringcompare) 5359 << isa<ObjCEncodeExpr>(literalStringStripped) 5360 << literalString->getSourceRange()); 5361 } 5362 } 5363 5364 // The result of comparisons is 'bool' in C++, 'int' in C. 5365 QualType ResultTy = getLangOptions().CPlusPlus ? Context.BoolTy:Context.IntTy; 5366 5367 if (isRelational) { 5368 if (lType->isRealType() && rType->isRealType()) 5369 return ResultTy; 5370 } else { 5371 // Check for comparisons of floating point operands using != and ==. 5372 if (lType->isFloatingType() && rType->isFloatingType()) 5373 CheckFloatComparison(Loc,lex,rex); 5374 5375 if (lType->isArithmeticType() && rType->isArithmeticType()) 5376 return ResultTy; 5377 } 5378 5379 bool LHSIsNull = lex->isNullPointerConstant(Context, 5380 Expr::NPC_ValueDependentIsNull); 5381 bool RHSIsNull = rex->isNullPointerConstant(Context, 5382 Expr::NPC_ValueDependentIsNull); 5383 5384 // All of the following pointer related warnings are GCC extensions, except 5385 // when handling null pointer constants. One day, we can consider making them 5386 // errors (when -pedantic-errors is enabled). 5387 if (lType->isPointerType() && rType->isPointerType()) { // C99 6.5.8p2 5388 QualType LCanPointeeTy = 5389 Context.getCanonicalType(lType->getAs<PointerType>()->getPointeeType()); 5390 QualType RCanPointeeTy = 5391 Context.getCanonicalType(rType->getAs<PointerType>()->getPointeeType()); 5392 5393 if (getLangOptions().CPlusPlus) { 5394 if (LCanPointeeTy == RCanPointeeTy) 5395 return ResultTy; 5396 if (!isRelational && 5397 (LCanPointeeTy->isVoidType() || RCanPointeeTy->isVoidType())) { 5398 // Valid unless comparison between non-null pointer and function pointer 5399 // This is a gcc extension compatibility comparison. 5400 if ((LCanPointeeTy->isFunctionType() || RCanPointeeTy->isFunctionType()) 5401 && !LHSIsNull && !RHSIsNull) { 5402 Diag(Loc, diag::ext_typecheck_comparison_of_fptr_to_void) 5403 << lType << rType << lex->getSourceRange() << rex->getSourceRange(); 5404 ImpCastExprToType(rex, lType, CastExpr::CK_BitCast); 5405 return ResultTy; 5406 } 5407 } 5408 // C++ [expr.rel]p2: 5409 // [...] Pointer conversions (4.10) and qualification 5410 // conversions (4.4) are performed on pointer operands (or on 5411 // a pointer operand and a null pointer constant) to bring 5412 // them to their composite pointer type. [...] 5413 // 5414 // C++ [expr.eq]p1 uses the same notion for (in)equality 5415 // comparisons of pointers. 5416 bool NonStandardCompositeType = false; 5417 QualType T = FindCompositePointerType(Loc, lex, rex, 5418 isSFINAEContext()? 0 : &NonStandardCompositeType); 5419 if (T.isNull()) { 5420 Diag(Loc, diag::err_typecheck_comparison_of_distinct_pointers) 5421 << lType << rType << lex->getSourceRange() << rex->getSourceRange(); 5422 return QualType(); 5423 } else if (NonStandardCompositeType) { 5424 Diag(Loc, 5425 diag::ext_typecheck_comparison_of_distinct_pointers_nonstandard) 5426 << lType << rType << T 5427 << lex->getSourceRange() << rex->getSourceRange(); 5428 } 5429 5430 ImpCastExprToType(lex, T, CastExpr::CK_BitCast); 5431 ImpCastExprToType(rex, T, CastExpr::CK_BitCast); 5432 return ResultTy; 5433 } 5434 // C99 6.5.9p2 and C99 6.5.8p2 5435 if (Context.typesAreCompatible(LCanPointeeTy.getUnqualifiedType(), 5436 RCanPointeeTy.getUnqualifiedType())) { 5437 // Valid unless a relational comparison of function pointers 5438 if (isRelational && LCanPointeeTy->isFunctionType()) { 5439 Diag(Loc, diag::ext_typecheck_ordered_comparison_of_function_pointers) 5440 << lType << rType << lex->getSourceRange() << rex->getSourceRange(); 5441 } 5442 } else if (!isRelational && 5443 (LCanPointeeTy->isVoidType() || RCanPointeeTy->isVoidType())) { 5444 // Valid unless comparison between non-null pointer and function pointer 5445 if ((LCanPointeeTy->isFunctionType() || RCanPointeeTy->isFunctionType()) 5446 && !LHSIsNull && !RHSIsNull) { 5447 Diag(Loc, diag::ext_typecheck_comparison_of_fptr_to_void) 5448 << lType << rType << lex->getSourceRange() << rex->getSourceRange(); 5449 } 5450 } else { 5451 // Invalid 5452 Diag(Loc, diag::ext_typecheck_comparison_of_distinct_pointers) 5453 << lType << rType << lex->getSourceRange() << rex->getSourceRange(); 5454 } 5455 if (LCanPointeeTy != RCanPointeeTy) 5456 ImpCastExprToType(rex, lType, CastExpr::CK_BitCast); 5457 return ResultTy; 5458 } 5459 5460 if (getLangOptions().CPlusPlus) { 5461 // Comparison of pointers with null pointer constants and equality 5462 // comparisons of member pointers to null pointer constants. 5463 if (RHSIsNull && 5464 (lType->isPointerType() || 5465 (!isRelational && lType->isMemberPointerType()))) { 5466 ImpCastExprToType(rex, lType, CastExpr::CK_NullToMemberPointer); 5467 return ResultTy; 5468 } 5469 if (LHSIsNull && 5470 (rType->isPointerType() || 5471 (!isRelational && rType->isMemberPointerType()))) { 5472 ImpCastExprToType(lex, rType, CastExpr::CK_NullToMemberPointer); 5473 return ResultTy; 5474 } 5475 5476 // Comparison of member pointers. 5477 if (!isRelational && 5478 lType->isMemberPointerType() && rType->isMemberPointerType()) { 5479 // C++ [expr.eq]p2: 5480 // In addition, pointers to members can be compared, or a pointer to 5481 // member and a null pointer constant. Pointer to member conversions 5482 // (4.11) and qualification conversions (4.4) are performed to bring 5483 // them to a common type. If one operand is a null pointer constant, 5484 // the common type is the type of the other operand. Otherwise, the 5485 // common type is a pointer to member type similar (4.4) to the type 5486 // of one of the operands, with a cv-qualification signature (4.4) 5487 // that is the union of the cv-qualification signatures of the operand 5488 // types. 5489 bool NonStandardCompositeType = false; 5490 QualType T = FindCompositePointerType(Loc, lex, rex, 5491 isSFINAEContext()? 0 : &NonStandardCompositeType); 5492 if (T.isNull()) { 5493 Diag(Loc, diag::err_typecheck_comparison_of_distinct_pointers) 5494 << lType << rType << lex->getSourceRange() << rex->getSourceRange(); 5495 return QualType(); 5496 } else if (NonStandardCompositeType) { 5497 Diag(Loc, 5498 diag::ext_typecheck_comparison_of_distinct_pointers_nonstandard) 5499 << lType << rType << T 5500 << lex->getSourceRange() << rex->getSourceRange(); 5501 } 5502 5503 ImpCastExprToType(lex, T, CastExpr::CK_BitCast); 5504 ImpCastExprToType(rex, T, CastExpr::CK_BitCast); 5505 return ResultTy; 5506 } 5507 5508 // Comparison of nullptr_t with itself. 5509 if (lType->isNullPtrType() && rType->isNullPtrType()) 5510 return ResultTy; 5511 } 5512 5513 // Handle block pointer types. 5514 if (!isRelational && lType->isBlockPointerType() && rType->isBlockPointerType()) { 5515 QualType lpointee = lType->getAs<BlockPointerType>()->getPointeeType(); 5516 QualType rpointee = rType->getAs<BlockPointerType>()->getPointeeType(); 5517 5518 if (!LHSIsNull && !RHSIsNull && 5519 !Context.typesAreCompatible(lpointee, rpointee)) { 5520 Diag(Loc, diag::err_typecheck_comparison_of_distinct_blocks) 5521 << lType << rType << lex->getSourceRange() << rex->getSourceRange(); 5522 } 5523 ImpCastExprToType(rex, lType, CastExpr::CK_BitCast); 5524 return ResultTy; 5525 } 5526 // Allow block pointers to be compared with null pointer constants. 5527 if (!isRelational 5528 && ((lType->isBlockPointerType() && rType->isPointerType()) 5529 || (lType->isPointerType() && rType->isBlockPointerType()))) { 5530 if (!LHSIsNull && !RHSIsNull) { 5531 if (!((rType->isPointerType() && rType->getAs<PointerType>() 5532 ->getPointeeType()->isVoidType()) 5533 || (lType->isPointerType() && lType->getAs<PointerType>() 5534 ->getPointeeType()->isVoidType()))) 5535 Diag(Loc, diag::err_typecheck_comparison_of_distinct_blocks) 5536 << lType << rType << lex->getSourceRange() << rex->getSourceRange(); 5537 } 5538 ImpCastExprToType(rex, lType, CastExpr::CK_BitCast); 5539 return ResultTy; 5540 } 5541 5542 if ((lType->isObjCObjectPointerType() || rType->isObjCObjectPointerType())) { 5543 if (lType->isPointerType() || rType->isPointerType()) { 5544 const PointerType *LPT = lType->getAs<PointerType>(); 5545 const PointerType *RPT = rType->getAs<PointerType>(); 5546 bool LPtrToVoid = LPT ? 5547 Context.getCanonicalType(LPT->getPointeeType())->isVoidType() : false; 5548 bool RPtrToVoid = RPT ? 5549 Context.getCanonicalType(RPT->getPointeeType())->isVoidType() : false; 5550 5551 if (!LPtrToVoid && !RPtrToVoid && 5552 !Context.typesAreCompatible(lType, rType)) { 5553 Diag(Loc, diag::ext_typecheck_comparison_of_distinct_pointers) 5554 << lType << rType << lex->getSourceRange() << rex->getSourceRange(); 5555 } 5556 ImpCastExprToType(rex, lType, CastExpr::CK_BitCast); 5557 return ResultTy; 5558 } 5559 if (lType->isObjCObjectPointerType() && rType->isObjCObjectPointerType()) { 5560 if (!Context.areComparableObjCPointerTypes(lType, rType)) 5561 Diag(Loc, diag::ext_typecheck_comparison_of_distinct_pointers) 5562 << lType << rType << lex->getSourceRange() << rex->getSourceRange(); 5563 ImpCastExprToType(rex, lType, CastExpr::CK_BitCast); 5564 return ResultTy; 5565 } 5566 } 5567 if (lType->isAnyPointerType() && rType->isIntegerType()) { 5568 unsigned DiagID = 0; 5569 if (RHSIsNull) { 5570 if (isRelational) 5571 DiagID = diag::ext_typecheck_ordered_comparison_of_pointer_and_zero; 5572 } else if (isRelational) 5573 DiagID = diag::ext_typecheck_ordered_comparison_of_pointer_integer; 5574 else 5575 DiagID = diag::ext_typecheck_comparison_of_pointer_integer; 5576 5577 if (DiagID) { 5578 Diag(Loc, DiagID) 5579 << lType << rType << lex->getSourceRange() << rex->getSourceRange(); 5580 } 5581 ImpCastExprToType(rex, lType, CastExpr::CK_IntegralToPointer); 5582 return ResultTy; 5583 } 5584 if (lType->isIntegerType() && rType->isAnyPointerType()) { 5585 unsigned DiagID = 0; 5586 if (LHSIsNull) { 5587 if (isRelational) 5588 DiagID = diag::ext_typecheck_ordered_comparison_of_pointer_and_zero; 5589 } else if (isRelational) 5590 DiagID = diag::ext_typecheck_ordered_comparison_of_pointer_integer; 5591 else 5592 DiagID = diag::ext_typecheck_comparison_of_pointer_integer; 5593 5594 if (DiagID) { 5595 Diag(Loc, DiagID) 5596 << lType << rType << lex->getSourceRange() << rex->getSourceRange(); 5597 } 5598 ImpCastExprToType(lex, rType, CastExpr::CK_IntegralToPointer); 5599 return ResultTy; 5600 } 5601 // Handle block pointers. 5602 if (!isRelational && RHSIsNull 5603 && lType->isBlockPointerType() && rType->isIntegerType()) { 5604 ImpCastExprToType(rex, lType, CastExpr::CK_IntegralToPointer); 5605 return ResultTy; 5606 } 5607 if (!isRelational && LHSIsNull 5608 && lType->isIntegerType() && rType->isBlockPointerType()) { 5609 ImpCastExprToType(lex, rType, CastExpr::CK_IntegralToPointer); 5610 return ResultTy; 5611 } 5612 return InvalidOperands(Loc, lex, rex); 5613} 5614 5615/// CheckVectorCompareOperands - vector comparisons are a clang extension that 5616/// operates on extended vector types. Instead of producing an IntTy result, 5617/// like a scalar comparison, a vector comparison produces a vector of integer 5618/// types. 5619QualType Sema::CheckVectorCompareOperands(Expr *&lex, Expr *&rex, 5620 SourceLocation Loc, 5621 bool isRelational) { 5622 // Check to make sure we're operating on vectors of the same type and width, 5623 // Allowing one side to be a scalar of element type. 5624 QualType vType = CheckVectorOperands(Loc, lex, rex); 5625 if (vType.isNull()) 5626 return vType; 5627 5628 QualType lType = lex->getType(); 5629 QualType rType = rex->getType(); 5630 5631 // For non-floating point types, check for self-comparisons of the form 5632 // x == x, x != x, x < x, etc. These always evaluate to a constant, and 5633 // often indicate logic errors in the program. 5634 if (!lType->isFloatingType()) { 5635 if (DeclRefExpr* DRL = dyn_cast<DeclRefExpr>(lex->IgnoreParens())) 5636 if (DeclRefExpr* DRR = dyn_cast<DeclRefExpr>(rex->IgnoreParens())) 5637 if (DRL->getDecl() == DRR->getDecl()) 5638 DiagRuntimeBehavior(Loc, PDiag(diag::warn_selfcomparison)); 5639 } 5640 5641 // Check for comparisons of floating point operands using != and ==. 5642 if (!isRelational && lType->isFloatingType()) { 5643 assert (rType->isFloatingType()); 5644 CheckFloatComparison(Loc,lex,rex); 5645 } 5646 5647 // Return the type for the comparison, which is the same as vector type for 5648 // integer vectors, or an integer type of identical size and number of 5649 // elements for floating point vectors. 5650 if (lType->isIntegerType()) 5651 return lType; 5652 5653 const VectorType *VTy = lType->getAs<VectorType>(); 5654 unsigned TypeSize = Context.getTypeSize(VTy->getElementType()); 5655 if (TypeSize == Context.getTypeSize(Context.IntTy)) 5656 return Context.getExtVectorType(Context.IntTy, VTy->getNumElements()); 5657 if (TypeSize == Context.getTypeSize(Context.LongTy)) 5658 return Context.getExtVectorType(Context.LongTy, VTy->getNumElements()); 5659 5660 assert(TypeSize == Context.getTypeSize(Context.LongLongTy) && 5661 "Unhandled vector element size in vector compare"); 5662 return Context.getExtVectorType(Context.LongLongTy, VTy->getNumElements()); 5663} 5664 5665inline QualType Sema::CheckBitwiseOperands( 5666 Expr *&lex, Expr *&rex, SourceLocation Loc, bool isCompAssign) { 5667 if (lex->getType()->isVectorType() || rex->getType()->isVectorType()) 5668 return CheckVectorOperands(Loc, lex, rex); 5669 5670 QualType compType = UsualArithmeticConversions(lex, rex, isCompAssign); 5671 5672 if (lex->getType()->isIntegerType() && rex->getType()->isIntegerType()) 5673 return compType; 5674 return InvalidOperands(Loc, lex, rex); 5675} 5676 5677inline QualType Sema::CheckLogicalOperands( // C99 6.5.[13,14] 5678 Expr *&lex, Expr *&rex, SourceLocation Loc) { 5679 if (!Context.getLangOptions().CPlusPlus) { 5680 UsualUnaryConversions(lex); 5681 UsualUnaryConversions(rex); 5682 5683 if (!lex->getType()->isScalarType() || !rex->getType()->isScalarType()) 5684 return InvalidOperands(Loc, lex, rex); 5685 5686 return Context.IntTy; 5687 } 5688 5689 // C++ [expr.log.and]p1 5690 // C++ [expr.log.or]p1 5691 // The operands are both implicitly converted to type bool (clause 4). 5692 StandardConversionSequence LHS; 5693 if (!IsStandardConversion(lex, Context.BoolTy, 5694 /*InOverloadResolution=*/false, LHS)) 5695 return InvalidOperands(Loc, lex, rex); 5696 5697 if (PerformImplicitConversion(lex, Context.BoolTy, LHS, 5698 AA_Passing, /*IgnoreBaseAccess=*/false)) 5699 return InvalidOperands(Loc, lex, rex); 5700 5701 StandardConversionSequence RHS; 5702 if (!IsStandardConversion(rex, Context.BoolTy, 5703 /*InOverloadResolution=*/false, RHS)) 5704 return InvalidOperands(Loc, lex, rex); 5705 5706 if (PerformImplicitConversion(rex, Context.BoolTy, RHS, 5707 AA_Passing, /*IgnoreBaseAccess=*/false)) 5708 return InvalidOperands(Loc, lex, rex); 5709 5710 // C++ [expr.log.and]p2 5711 // C++ [expr.log.or]p2 5712 // The result is a bool. 5713 return Context.BoolTy; 5714} 5715 5716/// IsReadonlyProperty - Verify that otherwise a valid l-value expression 5717/// is a read-only property; return true if so. A readonly property expression 5718/// depends on various declarations and thus must be treated specially. 5719/// 5720static bool IsReadonlyProperty(Expr *E, Sema &S) { 5721 if (E->getStmtClass() == Expr::ObjCPropertyRefExprClass) { 5722 const ObjCPropertyRefExpr* PropExpr = cast<ObjCPropertyRefExpr>(E); 5723 if (ObjCPropertyDecl *PDecl = PropExpr->getProperty()) { 5724 QualType BaseType = PropExpr->getBase()->getType(); 5725 if (const ObjCObjectPointerType *OPT = 5726 BaseType->getAsObjCInterfacePointerType()) 5727 if (ObjCInterfaceDecl *IFace = OPT->getInterfaceDecl()) 5728 if (S.isPropertyReadonly(PDecl, IFace)) 5729 return true; 5730 } 5731 } 5732 return false; 5733} 5734 5735/// CheckForModifiableLvalue - Verify that E is a modifiable lvalue. If not, 5736/// emit an error and return true. If so, return false. 5737static bool CheckForModifiableLvalue(Expr *E, SourceLocation Loc, Sema &S) { 5738 SourceLocation OrigLoc = Loc; 5739 Expr::isModifiableLvalueResult IsLV = E->isModifiableLvalue(S.Context, 5740 &Loc); 5741 if (IsLV == Expr::MLV_Valid && IsReadonlyProperty(E, S)) 5742 IsLV = Expr::MLV_ReadonlyProperty; 5743 if (IsLV == Expr::MLV_Valid) 5744 return false; 5745 5746 unsigned Diag = 0; 5747 bool NeedType = false; 5748 switch (IsLV) { // C99 6.5.16p2 5749 case Expr::MLV_ConstQualified: Diag = diag::err_typecheck_assign_const; break; 5750 case Expr::MLV_ArrayType: 5751 Diag = diag::err_typecheck_array_not_modifiable_lvalue; 5752 NeedType = true; 5753 break; 5754 case Expr::MLV_NotObjectType: 5755 Diag = diag::err_typecheck_non_object_not_modifiable_lvalue; 5756 NeedType = true; 5757 break; 5758 case Expr::MLV_LValueCast: 5759 Diag = diag::err_typecheck_lvalue_casts_not_supported; 5760 break; 5761 case Expr::MLV_Valid: 5762 llvm_unreachable("did not take early return for MLV_Valid"); 5763 case Expr::MLV_InvalidExpression: 5764 case Expr::MLV_MemberFunction: 5765 case Expr::MLV_ClassTemporary: 5766 Diag = diag::err_typecheck_expression_not_modifiable_lvalue; 5767 break; 5768 case Expr::MLV_IncompleteType: 5769 case Expr::MLV_IncompleteVoidType: 5770 return S.RequireCompleteType(Loc, E->getType(), 5771 S.PDiag(diag::err_typecheck_incomplete_type_not_modifiable_lvalue) 5772 << E->getSourceRange()); 5773 case Expr::MLV_DuplicateVectorComponents: 5774 Diag = diag::err_typecheck_duplicate_vector_components_not_mlvalue; 5775 break; 5776 case Expr::MLV_NotBlockQualified: 5777 Diag = diag::err_block_decl_ref_not_modifiable_lvalue; 5778 break; 5779 case Expr::MLV_ReadonlyProperty: 5780 Diag = diag::error_readonly_property_assignment; 5781 break; 5782 case Expr::MLV_NoSetterProperty: 5783 Diag = diag::error_nosetter_property_assignment; 5784 break; 5785 case Expr::MLV_SubObjCPropertySetting: 5786 Diag = diag::error_no_subobject_property_setting; 5787 break; 5788 } 5789 5790 SourceRange Assign; 5791 if (Loc != OrigLoc) 5792 Assign = SourceRange(OrigLoc, OrigLoc); 5793 if (NeedType) 5794 S.Diag(Loc, Diag) << E->getType() << E->getSourceRange() << Assign; 5795 else 5796 S.Diag(Loc, Diag) << E->getSourceRange() << Assign; 5797 return true; 5798} 5799 5800 5801 5802// C99 6.5.16.1 5803QualType Sema::CheckAssignmentOperands(Expr *LHS, Expr *&RHS, 5804 SourceLocation Loc, 5805 QualType CompoundType) { 5806 // Verify that LHS is a modifiable lvalue, and emit error if not. 5807 if (CheckForModifiableLvalue(LHS, Loc, *this)) 5808 return QualType(); 5809 5810 QualType LHSType = LHS->getType(); 5811 QualType RHSType = CompoundType.isNull() ? RHS->getType() : CompoundType; 5812 5813 AssignConvertType ConvTy; 5814 if (CompoundType.isNull()) { 5815 // Simple assignment "x = y". 5816 ConvTy = CheckSingleAssignmentConstraints(LHSType, RHS); 5817 // Special case of NSObject attributes on c-style pointer types. 5818 if (ConvTy == IncompatiblePointer && 5819 ((Context.isObjCNSObjectType(LHSType) && 5820 RHSType->isObjCObjectPointerType()) || 5821 (Context.isObjCNSObjectType(RHSType) && 5822 LHSType->isObjCObjectPointerType()))) 5823 ConvTy = Compatible; 5824 5825 // If the RHS is a unary plus or minus, check to see if they = and + are 5826 // right next to each other. If so, the user may have typo'd "x =+ 4" 5827 // instead of "x += 4". 5828 Expr *RHSCheck = RHS; 5829 if (ImplicitCastExpr *ICE = dyn_cast<ImplicitCastExpr>(RHSCheck)) 5830 RHSCheck = ICE->getSubExpr(); 5831 if (UnaryOperator *UO = dyn_cast<UnaryOperator>(RHSCheck)) { 5832 if ((UO->getOpcode() == UnaryOperator::Plus || 5833 UO->getOpcode() == UnaryOperator::Minus) && 5834 Loc.isFileID() && UO->getOperatorLoc().isFileID() && 5835 // Only if the two operators are exactly adjacent. 5836 Loc.getFileLocWithOffset(1) == UO->getOperatorLoc() && 5837 // And there is a space or other character before the subexpr of the 5838 // unary +/-. We don't want to warn on "x=-1". 5839 Loc.getFileLocWithOffset(2) != UO->getSubExpr()->getLocStart() && 5840 UO->getSubExpr()->getLocStart().isFileID()) { 5841 Diag(Loc, diag::warn_not_compound_assign) 5842 << (UO->getOpcode() == UnaryOperator::Plus ? "+" : "-") 5843 << SourceRange(UO->getOperatorLoc(), UO->getOperatorLoc()); 5844 } 5845 } 5846 } else { 5847 // Compound assignment "x += y" 5848 ConvTy = CheckAssignmentConstraints(LHSType, RHSType); 5849 } 5850 5851 if (DiagnoseAssignmentResult(ConvTy, Loc, LHSType, RHSType, 5852 RHS, AA_Assigning)) 5853 return QualType(); 5854 5855 // C99 6.5.16p3: The type of an assignment expression is the type of the 5856 // left operand unless the left operand has qualified type, in which case 5857 // it is the unqualified version of the type of the left operand. 5858 // C99 6.5.16.1p2: In simple assignment, the value of the right operand 5859 // is converted to the type of the assignment expression (above). 5860 // C++ 5.17p1: the type of the assignment expression is that of its left 5861 // operand. 5862 return LHSType.getUnqualifiedType(); 5863} 5864 5865// C99 6.5.17 5866QualType Sema::CheckCommaOperands(Expr *LHS, Expr *&RHS, SourceLocation Loc) { 5867 // Comma performs lvalue conversion (C99 6.3.2.1), but not unary conversions. 5868 // C++ does not perform this conversion (C++ [expr.comma]p1). 5869 if (!getLangOptions().CPlusPlus) 5870 DefaultFunctionArrayLvalueConversion(RHS); 5871 5872 // FIXME: Check that RHS type is complete in C mode (it's legal for it to be 5873 // incomplete in C++). 5874 5875 return RHS->getType(); 5876} 5877 5878/// CheckIncrementDecrementOperand - unlike most "Check" methods, this routine 5879/// doesn't need to call UsualUnaryConversions or UsualArithmeticConversions. 5880QualType Sema::CheckIncrementDecrementOperand(Expr *Op, SourceLocation OpLoc, 5881 bool isInc, bool isPrefix) { 5882 if (Op->isTypeDependent()) 5883 return Context.DependentTy; 5884 5885 QualType ResType = Op->getType(); 5886 assert(!ResType.isNull() && "no type for increment/decrement expression"); 5887 5888 if (getLangOptions().CPlusPlus && ResType->isBooleanType()) { 5889 // Decrement of bool is not allowed. 5890 if (!isInc) { 5891 Diag(OpLoc, diag::err_decrement_bool) << Op->getSourceRange(); 5892 return QualType(); 5893 } 5894 // Increment of bool sets it to true, but is deprecated. 5895 Diag(OpLoc, diag::warn_increment_bool) << Op->getSourceRange(); 5896 } else if (ResType->isRealType()) { 5897 // OK! 5898 } else if (ResType->isAnyPointerType()) { 5899 QualType PointeeTy = ResType->getPointeeType(); 5900 5901 // C99 6.5.2.4p2, 6.5.6p2 5902 if (PointeeTy->isVoidType()) { 5903 if (getLangOptions().CPlusPlus) { 5904 Diag(OpLoc, diag::err_typecheck_pointer_arith_void_type) 5905 << Op->getSourceRange(); 5906 return QualType(); 5907 } 5908 5909 // Pointer to void is a GNU extension in C. 5910 Diag(OpLoc, diag::ext_gnu_void_ptr) << Op->getSourceRange(); 5911 } else if (PointeeTy->isFunctionType()) { 5912 if (getLangOptions().CPlusPlus) { 5913 Diag(OpLoc, diag::err_typecheck_pointer_arith_function_type) 5914 << Op->getType() << Op->getSourceRange(); 5915 return QualType(); 5916 } 5917 5918 Diag(OpLoc, diag::ext_gnu_ptr_func_arith) 5919 << ResType << Op->getSourceRange(); 5920 } else if (RequireCompleteType(OpLoc, PointeeTy, 5921 PDiag(diag::err_typecheck_arithmetic_incomplete_type) 5922 << Op->getSourceRange() 5923 << ResType)) 5924 return QualType(); 5925 // Diagnose bad cases where we step over interface counts. 5926 else if (PointeeTy->isObjCObjectType() && LangOpts.ObjCNonFragileABI) { 5927 Diag(OpLoc, diag::err_arithmetic_nonfragile_interface) 5928 << PointeeTy << Op->getSourceRange(); 5929 return QualType(); 5930 } 5931 } else if (ResType->isAnyComplexType()) { 5932 // C99 does not support ++/-- on complex types, we allow as an extension. 5933 Diag(OpLoc, diag::ext_integer_increment_complex) 5934 << ResType << Op->getSourceRange(); 5935 } else { 5936 Diag(OpLoc, diag::err_typecheck_illegal_increment_decrement) 5937 << ResType << int(isInc) << Op->getSourceRange(); 5938 return QualType(); 5939 } 5940 // At this point, we know we have a real, complex or pointer type. 5941 // Now make sure the operand is a modifiable lvalue. 5942 if (CheckForModifiableLvalue(Op, OpLoc, *this)) 5943 return QualType(); 5944 // In C++, a prefix increment is the same type as the operand. Otherwise 5945 // (in C or with postfix), the increment is the unqualified type of the 5946 // operand. 5947 return isPrefix && getLangOptions().CPlusPlus 5948 ? ResType : ResType.getUnqualifiedType(); 5949} 5950 5951/// getPrimaryDecl - Helper function for CheckAddressOfOperand(). 5952/// This routine allows us to typecheck complex/recursive expressions 5953/// where the declaration is needed for type checking. We only need to 5954/// handle cases when the expression references a function designator 5955/// or is an lvalue. Here are some examples: 5956/// - &(x) => x 5957/// - &*****f => f for f a function designator. 5958/// - &s.xx => s 5959/// - &s.zz[1].yy -> s, if zz is an array 5960/// - *(x + 1) -> x, if x is an array 5961/// - &"123"[2] -> 0 5962/// - & __real__ x -> x 5963static NamedDecl *getPrimaryDecl(Expr *E) { 5964 switch (E->getStmtClass()) { 5965 case Stmt::DeclRefExprClass: 5966 return cast<DeclRefExpr>(E)->getDecl(); 5967 case Stmt::MemberExprClass: 5968 // If this is an arrow operator, the address is an offset from 5969 // the base's value, so the object the base refers to is 5970 // irrelevant. 5971 if (cast<MemberExpr>(E)->isArrow()) 5972 return 0; 5973 // Otherwise, the expression refers to a part of the base 5974 return getPrimaryDecl(cast<MemberExpr>(E)->getBase()); 5975 case Stmt::ArraySubscriptExprClass: { 5976 // FIXME: This code shouldn't be necessary! We should catch the implicit 5977 // promotion of register arrays earlier. 5978 Expr* Base = cast<ArraySubscriptExpr>(E)->getBase(); 5979 if (ImplicitCastExpr* ICE = dyn_cast<ImplicitCastExpr>(Base)) { 5980 if (ICE->getSubExpr()->getType()->isArrayType()) 5981 return getPrimaryDecl(ICE->getSubExpr()); 5982 } 5983 return 0; 5984 } 5985 case Stmt::UnaryOperatorClass: { 5986 UnaryOperator *UO = cast<UnaryOperator>(E); 5987 5988 switch(UO->getOpcode()) { 5989 case UnaryOperator::Real: 5990 case UnaryOperator::Imag: 5991 case UnaryOperator::Extension: 5992 return getPrimaryDecl(UO->getSubExpr()); 5993 default: 5994 return 0; 5995 } 5996 } 5997 case Stmt::ParenExprClass: 5998 return getPrimaryDecl(cast<ParenExpr>(E)->getSubExpr()); 5999 case Stmt::ImplicitCastExprClass: 6000 // If the result of an implicit cast is an l-value, we care about 6001 // the sub-expression; otherwise, the result here doesn't matter. 6002 return getPrimaryDecl(cast<ImplicitCastExpr>(E)->getSubExpr()); 6003 default: 6004 return 0; 6005 } 6006} 6007 6008/// CheckAddressOfOperand - The operand of & must be either a function 6009/// designator or an lvalue designating an object. If it is an lvalue, the 6010/// object cannot be declared with storage class register or be a bit field. 6011/// Note: The usual conversions are *not* applied to the operand of the & 6012/// operator (C99 6.3.2.1p[2-4]), and its result is never an lvalue. 6013/// In C++, the operand might be an overloaded function name, in which case 6014/// we allow the '&' but retain the overloaded-function type. 6015QualType Sema::CheckAddressOfOperand(Expr *op, SourceLocation OpLoc) { 6016 // Make sure to ignore parentheses in subsequent checks 6017 op = op->IgnoreParens(); 6018 6019 if (op->isTypeDependent()) 6020 return Context.DependentTy; 6021 6022 if (getLangOptions().C99) { 6023 // Implement C99-only parts of addressof rules. 6024 if (UnaryOperator* uOp = dyn_cast<UnaryOperator>(op)) { 6025 if (uOp->getOpcode() == UnaryOperator::Deref) 6026 // Per C99 6.5.3.2, the address of a deref always returns a valid result 6027 // (assuming the deref expression is valid). 6028 return uOp->getSubExpr()->getType(); 6029 } 6030 // Technically, there should be a check for array subscript 6031 // expressions here, but the result of one is always an lvalue anyway. 6032 } 6033 NamedDecl *dcl = getPrimaryDecl(op); 6034 Expr::isLvalueResult lval = op->isLvalue(Context); 6035 6036 MemberExpr *ME = dyn_cast<MemberExpr>(op); 6037 if (lval == Expr::LV_MemberFunction && ME && 6038 isa<CXXMethodDecl>(ME->getMemberDecl())) { 6039 ValueDecl *dcl = cast<MemberExpr>(op)->getMemberDecl(); 6040 // &f where f is a member of the current object, or &o.f, or &p->f 6041 // All these are not allowed, and we need to catch them before the dcl 6042 // branch of the if, below. 6043 Diag(OpLoc, diag::err_unqualified_pointer_member_function) 6044 << dcl; 6045 // FIXME: Improve this diagnostic and provide a fixit. 6046 6047 // Now recover by acting as if the function had been accessed qualified. 6048 return Context.getMemberPointerType(op->getType(), 6049 Context.getTypeDeclType(cast<RecordDecl>(dcl->getDeclContext())) 6050 .getTypePtr()); 6051 } else if (lval == Expr::LV_ClassTemporary) { 6052 Diag(OpLoc, isSFINAEContext()? diag::err_typecheck_addrof_class_temporary 6053 : diag::ext_typecheck_addrof_class_temporary) 6054 << op->getType() << op->getSourceRange(); 6055 if (isSFINAEContext()) 6056 return QualType(); 6057 } else if (lval != Expr::LV_Valid && lval != Expr::LV_IncompleteVoidType) { 6058 // C99 6.5.3.2p1 6059 // The operand must be either an l-value or a function designator 6060 if (!op->getType()->isFunctionType()) { 6061 // FIXME: emit more specific diag... 6062 Diag(OpLoc, diag::err_typecheck_invalid_lvalue_addrof) 6063 << op->getSourceRange(); 6064 return QualType(); 6065 } 6066 } else if (op->getBitField()) { // C99 6.5.3.2p1 6067 // The operand cannot be a bit-field 6068 Diag(OpLoc, diag::err_typecheck_address_of) 6069 << "bit-field" << op->getSourceRange(); 6070 return QualType(); 6071 } else if (op->refersToVectorElement()) { 6072 // The operand cannot be an element of a vector 6073 Diag(OpLoc, diag::err_typecheck_address_of) 6074 << "vector element" << op->getSourceRange(); 6075 return QualType(); 6076 } else if (isa<ObjCPropertyRefExpr>(op)) { 6077 // cannot take address of a property expression. 6078 Diag(OpLoc, diag::err_typecheck_address_of) 6079 << "property expression" << op->getSourceRange(); 6080 return QualType(); 6081 } else if (ConditionalOperator *CO = dyn_cast<ConditionalOperator>(op)) { 6082 // FIXME: Can LHS ever be null here? 6083 if (!CheckAddressOfOperand(CO->getTrueExpr(), OpLoc).isNull()) 6084 return CheckAddressOfOperand(CO->getFalseExpr(), OpLoc); 6085 } else if (isa<UnresolvedLookupExpr>(op)) { 6086 return Context.OverloadTy; 6087 } else if (dcl) { // C99 6.5.3.2p1 6088 // We have an lvalue with a decl. Make sure the decl is not declared 6089 // with the register storage-class specifier. 6090 if (const VarDecl *vd = dyn_cast<VarDecl>(dcl)) { 6091 if (vd->getStorageClass() == VarDecl::Register) { 6092 Diag(OpLoc, diag::err_typecheck_address_of) 6093 << "register variable" << op->getSourceRange(); 6094 return QualType(); 6095 } 6096 } else if (isa<FunctionTemplateDecl>(dcl)) { 6097 return Context.OverloadTy; 6098 } else if (FieldDecl *FD = dyn_cast<FieldDecl>(dcl)) { 6099 // Okay: we can take the address of a field. 6100 // Could be a pointer to member, though, if there is an explicit 6101 // scope qualifier for the class. 6102 if (isa<DeclRefExpr>(op) && cast<DeclRefExpr>(op)->getQualifier()) { 6103 DeclContext *Ctx = dcl->getDeclContext(); 6104 if (Ctx && Ctx->isRecord()) { 6105 if (FD->getType()->isReferenceType()) { 6106 Diag(OpLoc, 6107 diag::err_cannot_form_pointer_to_member_of_reference_type) 6108 << FD->getDeclName() << FD->getType(); 6109 return QualType(); 6110 } 6111 6112 return Context.getMemberPointerType(op->getType(), 6113 Context.getTypeDeclType(cast<RecordDecl>(Ctx)).getTypePtr()); 6114 } 6115 } 6116 } else if (CXXMethodDecl *MD = dyn_cast<CXXMethodDecl>(dcl)) { 6117 // Okay: we can take the address of a function. 6118 // As above. 6119 if (isa<DeclRefExpr>(op) && cast<DeclRefExpr>(op)->getQualifier() && 6120 MD->isInstance()) 6121 return Context.getMemberPointerType(op->getType(), 6122 Context.getTypeDeclType(MD->getParent()).getTypePtr()); 6123 } else if (!isa<FunctionDecl>(dcl)) 6124 assert(0 && "Unknown/unexpected decl type"); 6125 } 6126 6127 if (lval == Expr::LV_IncompleteVoidType) { 6128 // Taking the address of a void variable is technically illegal, but we 6129 // allow it in cases which are otherwise valid. 6130 // Example: "extern void x; void* y = &x;". 6131 Diag(OpLoc, diag::ext_typecheck_addrof_void) << op->getSourceRange(); 6132 } 6133 6134 // If the operand has type "type", the result has type "pointer to type". 6135 return Context.getPointerType(op->getType()); 6136} 6137 6138QualType Sema::CheckIndirectionOperand(Expr *Op, SourceLocation OpLoc) { 6139 if (Op->isTypeDependent()) 6140 return Context.DependentTy; 6141 6142 UsualUnaryConversions(Op); 6143 QualType Ty = Op->getType(); 6144 6145 // Note that per both C89 and C99, this is always legal, even if ptype is an 6146 // incomplete type or void. It would be possible to warn about dereferencing 6147 // a void pointer, but it's completely well-defined, and such a warning is 6148 // unlikely to catch any mistakes. 6149 if (const PointerType *PT = Ty->getAs<PointerType>()) 6150 return PT->getPointeeType(); 6151 6152 if (const ObjCObjectPointerType *OPT = Ty->getAs<ObjCObjectPointerType>()) 6153 return OPT->getPointeeType(); 6154 6155 Diag(OpLoc, diag::err_typecheck_indirection_requires_pointer) 6156 << Ty << Op->getSourceRange(); 6157 return QualType(); 6158} 6159 6160static inline BinaryOperator::Opcode ConvertTokenKindToBinaryOpcode( 6161 tok::TokenKind Kind) { 6162 BinaryOperator::Opcode Opc; 6163 switch (Kind) { 6164 default: assert(0 && "Unknown binop!"); 6165 case tok::periodstar: Opc = BinaryOperator::PtrMemD; break; 6166 case tok::arrowstar: Opc = BinaryOperator::PtrMemI; break; 6167 case tok::star: Opc = BinaryOperator::Mul; break; 6168 case tok::slash: Opc = BinaryOperator::Div; break; 6169 case tok::percent: Opc = BinaryOperator::Rem; break; 6170 case tok::plus: Opc = BinaryOperator::Add; break; 6171 case tok::minus: Opc = BinaryOperator::Sub; break; 6172 case tok::lessless: Opc = BinaryOperator::Shl; break; 6173 case tok::greatergreater: Opc = BinaryOperator::Shr; break; 6174 case tok::lessequal: Opc = BinaryOperator::LE; break; 6175 case tok::less: Opc = BinaryOperator::LT; break; 6176 case tok::greaterequal: Opc = BinaryOperator::GE; break; 6177 case tok::greater: Opc = BinaryOperator::GT; break; 6178 case tok::exclaimequal: Opc = BinaryOperator::NE; break; 6179 case tok::equalequal: Opc = BinaryOperator::EQ; break; 6180 case tok::amp: Opc = BinaryOperator::And; break; 6181 case tok::caret: Opc = BinaryOperator::Xor; break; 6182 case tok::pipe: Opc = BinaryOperator::Or; break; 6183 case tok::ampamp: Opc = BinaryOperator::LAnd; break; 6184 case tok::pipepipe: Opc = BinaryOperator::LOr; break; 6185 case tok::equal: Opc = BinaryOperator::Assign; break; 6186 case tok::starequal: Opc = BinaryOperator::MulAssign; break; 6187 case tok::slashequal: Opc = BinaryOperator::DivAssign; break; 6188 case tok::percentequal: Opc = BinaryOperator::RemAssign; break; 6189 case tok::plusequal: Opc = BinaryOperator::AddAssign; break; 6190 case tok::minusequal: Opc = BinaryOperator::SubAssign; break; 6191 case tok::lesslessequal: Opc = BinaryOperator::ShlAssign; break; 6192 case tok::greatergreaterequal: Opc = BinaryOperator::ShrAssign; break; 6193 case tok::ampequal: Opc = BinaryOperator::AndAssign; break; 6194 case tok::caretequal: Opc = BinaryOperator::XorAssign; break; 6195 case tok::pipeequal: Opc = BinaryOperator::OrAssign; break; 6196 case tok::comma: Opc = BinaryOperator::Comma; break; 6197 } 6198 return Opc; 6199} 6200 6201static inline UnaryOperator::Opcode ConvertTokenKindToUnaryOpcode( 6202 tok::TokenKind Kind) { 6203 UnaryOperator::Opcode Opc; 6204 switch (Kind) { 6205 default: assert(0 && "Unknown unary op!"); 6206 case tok::plusplus: Opc = UnaryOperator::PreInc; break; 6207 case tok::minusminus: Opc = UnaryOperator::PreDec; break; 6208 case tok::amp: Opc = UnaryOperator::AddrOf; break; 6209 case tok::star: Opc = UnaryOperator::Deref; break; 6210 case tok::plus: Opc = UnaryOperator::Plus; break; 6211 case tok::minus: Opc = UnaryOperator::Minus; break; 6212 case tok::tilde: Opc = UnaryOperator::Not; break; 6213 case tok::exclaim: Opc = UnaryOperator::LNot; break; 6214 case tok::kw___real: Opc = UnaryOperator::Real; break; 6215 case tok::kw___imag: Opc = UnaryOperator::Imag; break; 6216 case tok::kw___extension__: Opc = UnaryOperator::Extension; break; 6217 } 6218 return Opc; 6219} 6220 6221/// CreateBuiltinBinOp - Creates a new built-in binary operation with 6222/// operator @p Opc at location @c TokLoc. This routine only supports 6223/// built-in operations; ActOnBinOp handles overloaded operators. 6224Action::OwningExprResult Sema::CreateBuiltinBinOp(SourceLocation OpLoc, 6225 unsigned Op, 6226 Expr *lhs, Expr *rhs) { 6227 QualType ResultTy; // Result type of the binary operator. 6228 BinaryOperator::Opcode Opc = (BinaryOperator::Opcode)Op; 6229 // The following two variables are used for compound assignment operators 6230 QualType CompLHSTy; // Type of LHS after promotions for computation 6231 QualType CompResultTy; // Type of computation result 6232 6233 switch (Opc) { 6234 case BinaryOperator::Assign: 6235 ResultTy = CheckAssignmentOperands(lhs, rhs, OpLoc, QualType()); 6236 break; 6237 case BinaryOperator::PtrMemD: 6238 case BinaryOperator::PtrMemI: 6239 ResultTy = CheckPointerToMemberOperands(lhs, rhs, OpLoc, 6240 Opc == BinaryOperator::PtrMemI); 6241 break; 6242 case BinaryOperator::Mul: 6243 case BinaryOperator::Div: 6244 ResultTy = CheckMultiplyDivideOperands(lhs, rhs, OpLoc, false, 6245 Opc == BinaryOperator::Div); 6246 break; 6247 case BinaryOperator::Rem: 6248 ResultTy = CheckRemainderOperands(lhs, rhs, OpLoc); 6249 break; 6250 case BinaryOperator::Add: 6251 ResultTy = CheckAdditionOperands(lhs, rhs, OpLoc); 6252 break; 6253 case BinaryOperator::Sub: 6254 ResultTy = CheckSubtractionOperands(lhs, rhs, OpLoc); 6255 break; 6256 case BinaryOperator::Shl: 6257 case BinaryOperator::Shr: 6258 ResultTy = CheckShiftOperands(lhs, rhs, OpLoc); 6259 break; 6260 case BinaryOperator::LE: 6261 case BinaryOperator::LT: 6262 case BinaryOperator::GE: 6263 case BinaryOperator::GT: 6264 ResultTy = CheckCompareOperands(lhs, rhs, OpLoc, Opc, true); 6265 break; 6266 case BinaryOperator::EQ: 6267 case BinaryOperator::NE: 6268 ResultTy = CheckCompareOperands(lhs, rhs, OpLoc, Opc, false); 6269 break; 6270 case BinaryOperator::And: 6271 case BinaryOperator::Xor: 6272 case BinaryOperator::Or: 6273 ResultTy = CheckBitwiseOperands(lhs, rhs, OpLoc); 6274 break; 6275 case BinaryOperator::LAnd: 6276 case BinaryOperator::LOr: 6277 ResultTy = CheckLogicalOperands(lhs, rhs, OpLoc); 6278 break; 6279 case BinaryOperator::MulAssign: 6280 case BinaryOperator::DivAssign: 6281 CompResultTy = CheckMultiplyDivideOperands(lhs, rhs, OpLoc, true, 6282 Opc == BinaryOperator::DivAssign); 6283 CompLHSTy = CompResultTy; 6284 if (!CompResultTy.isNull()) 6285 ResultTy = CheckAssignmentOperands(lhs, rhs, OpLoc, CompResultTy); 6286 break; 6287 case BinaryOperator::RemAssign: 6288 CompResultTy = CheckRemainderOperands(lhs, rhs, OpLoc, true); 6289 CompLHSTy = CompResultTy; 6290 if (!CompResultTy.isNull()) 6291 ResultTy = CheckAssignmentOperands(lhs, rhs, OpLoc, CompResultTy); 6292 break; 6293 case BinaryOperator::AddAssign: 6294 CompResultTy = CheckAdditionOperands(lhs, rhs, OpLoc, &CompLHSTy); 6295 if (!CompResultTy.isNull()) 6296 ResultTy = CheckAssignmentOperands(lhs, rhs, OpLoc, CompResultTy); 6297 break; 6298 case BinaryOperator::SubAssign: 6299 CompResultTy = CheckSubtractionOperands(lhs, rhs, OpLoc, &CompLHSTy); 6300 if (!CompResultTy.isNull()) 6301 ResultTy = CheckAssignmentOperands(lhs, rhs, OpLoc, CompResultTy); 6302 break; 6303 case BinaryOperator::ShlAssign: 6304 case BinaryOperator::ShrAssign: 6305 CompResultTy = CheckShiftOperands(lhs, rhs, OpLoc, true); 6306 CompLHSTy = CompResultTy; 6307 if (!CompResultTy.isNull()) 6308 ResultTy = CheckAssignmentOperands(lhs, rhs, OpLoc, CompResultTy); 6309 break; 6310 case BinaryOperator::AndAssign: 6311 case BinaryOperator::XorAssign: 6312 case BinaryOperator::OrAssign: 6313 CompResultTy = CheckBitwiseOperands(lhs, rhs, OpLoc, true); 6314 CompLHSTy = CompResultTy; 6315 if (!CompResultTy.isNull()) 6316 ResultTy = CheckAssignmentOperands(lhs, rhs, OpLoc, CompResultTy); 6317 break; 6318 case BinaryOperator::Comma: 6319 ResultTy = CheckCommaOperands(lhs, rhs, OpLoc); 6320 break; 6321 } 6322 if (ResultTy.isNull()) 6323 return ExprError(); 6324 if (CompResultTy.isNull()) 6325 return Owned(new (Context) BinaryOperator(lhs, rhs, Opc, ResultTy, OpLoc)); 6326 else 6327 return Owned(new (Context) CompoundAssignOperator(lhs, rhs, Opc, ResultTy, 6328 CompLHSTy, CompResultTy, 6329 OpLoc)); 6330} 6331 6332/// SuggestParentheses - Emit a diagnostic together with a fixit hint that wraps 6333/// ParenRange in parentheses. 6334static void SuggestParentheses(Sema &Self, SourceLocation Loc, 6335 const PartialDiagnostic &PD, 6336 const PartialDiagnostic &FirstNote, 6337 SourceRange FirstParenRange, 6338 const PartialDiagnostic &SecondNote, 6339 SourceRange SecondParenRange) { 6340 Self.Diag(Loc, PD); 6341 6342 if (!FirstNote.getDiagID()) 6343 return; 6344 6345 SourceLocation EndLoc = Self.PP.getLocForEndOfToken(FirstParenRange.getEnd()); 6346 if (!FirstParenRange.getEnd().isFileID() || EndLoc.isInvalid()) { 6347 // We can't display the parentheses, so just return. 6348 return; 6349 } 6350 6351 Self.Diag(Loc, FirstNote) 6352 << FixItHint::CreateInsertion(FirstParenRange.getBegin(), "(") 6353 << FixItHint::CreateInsertion(EndLoc, ")"); 6354 6355 if (!SecondNote.getDiagID()) 6356 return; 6357 6358 EndLoc = Self.PP.getLocForEndOfToken(SecondParenRange.getEnd()); 6359 if (!SecondParenRange.getEnd().isFileID() || EndLoc.isInvalid()) { 6360 // We can't display the parentheses, so just dig the 6361 // warning/error and return. 6362 Self.Diag(Loc, SecondNote); 6363 return; 6364 } 6365 6366 Self.Diag(Loc, SecondNote) 6367 << FixItHint::CreateInsertion(SecondParenRange.getBegin(), "(") 6368 << FixItHint::CreateInsertion(EndLoc, ")"); 6369} 6370 6371/// DiagnoseBitwisePrecedence - Emit a warning when bitwise and comparison 6372/// operators are mixed in a way that suggests that the programmer forgot that 6373/// comparison operators have higher precedence. The most typical example of 6374/// such code is "flags & 0x0020 != 0", which is equivalent to "flags & 1". 6375static void DiagnoseBitwisePrecedence(Sema &Self, BinaryOperator::Opcode Opc, 6376 SourceLocation OpLoc,Expr *lhs,Expr *rhs){ 6377 typedef BinaryOperator BinOp; 6378 BinOp::Opcode lhsopc = static_cast<BinOp::Opcode>(-1), 6379 rhsopc = static_cast<BinOp::Opcode>(-1); 6380 if (BinOp *BO = dyn_cast<BinOp>(lhs)) 6381 lhsopc = BO->getOpcode(); 6382 if (BinOp *BO = dyn_cast<BinOp>(rhs)) 6383 rhsopc = BO->getOpcode(); 6384 6385 // Subs are not binary operators. 6386 if (lhsopc == -1 && rhsopc == -1) 6387 return; 6388 6389 // Bitwise operations are sometimes used as eager logical ops. 6390 // Don't diagnose this. 6391 if ((BinOp::isComparisonOp(lhsopc) || BinOp::isBitwiseOp(lhsopc)) && 6392 (BinOp::isComparisonOp(rhsopc) || BinOp::isBitwiseOp(rhsopc))) 6393 return; 6394 6395 if (BinOp::isComparisonOp(lhsopc)) 6396 SuggestParentheses(Self, OpLoc, 6397 Self.PDiag(diag::warn_precedence_bitwise_rel) 6398 << SourceRange(lhs->getLocStart(), OpLoc) 6399 << BinOp::getOpcodeStr(Opc) << BinOp::getOpcodeStr(lhsopc), 6400 Self.PDiag(diag::note_precedence_bitwise_first) 6401 << BinOp::getOpcodeStr(Opc), 6402 SourceRange(cast<BinOp>(lhs)->getRHS()->getLocStart(), rhs->getLocEnd()), 6403 Self.PDiag(diag::note_precedence_bitwise_silence) 6404 << BinOp::getOpcodeStr(lhsopc), 6405 lhs->getSourceRange()); 6406 else if (BinOp::isComparisonOp(rhsopc)) 6407 SuggestParentheses(Self, OpLoc, 6408 Self.PDiag(diag::warn_precedence_bitwise_rel) 6409 << SourceRange(OpLoc, rhs->getLocEnd()) 6410 << BinOp::getOpcodeStr(Opc) << BinOp::getOpcodeStr(rhsopc), 6411 Self.PDiag(diag::note_precedence_bitwise_first) 6412 << BinOp::getOpcodeStr(Opc), 6413 SourceRange(lhs->getLocEnd(), cast<BinOp>(rhs)->getLHS()->getLocStart()), 6414 Self.PDiag(diag::note_precedence_bitwise_silence) 6415 << BinOp::getOpcodeStr(rhsopc), 6416 rhs->getSourceRange()); 6417} 6418 6419/// DiagnoseBinOpPrecedence - Emit warnings for expressions with tricky 6420/// precedence. This currently diagnoses only "arg1 'bitwise' arg2 'eq' arg3". 6421/// But it could also warn about arg1 && arg2 || arg3, as GCC 4.3+ does. 6422static void DiagnoseBinOpPrecedence(Sema &Self, BinaryOperator::Opcode Opc, 6423 SourceLocation OpLoc, Expr *lhs, Expr *rhs){ 6424 if (BinaryOperator::isBitwiseOp(Opc)) 6425 DiagnoseBitwisePrecedence(Self, Opc, OpLoc, lhs, rhs); 6426} 6427 6428// Binary Operators. 'Tok' is the token for the operator. 6429Action::OwningExprResult Sema::ActOnBinOp(Scope *S, SourceLocation TokLoc, 6430 tok::TokenKind Kind, 6431 ExprArg LHS, ExprArg RHS) { 6432 BinaryOperator::Opcode Opc = ConvertTokenKindToBinaryOpcode(Kind); 6433 Expr *lhs = LHS.takeAs<Expr>(), *rhs = RHS.takeAs<Expr>(); 6434 6435 assert((lhs != 0) && "ActOnBinOp(): missing left expression"); 6436 assert((rhs != 0) && "ActOnBinOp(): missing right expression"); 6437 6438 // Emit warnings for tricky precedence issues, e.g. "bitfield & 0x4 == 0" 6439 DiagnoseBinOpPrecedence(*this, Opc, TokLoc, lhs, rhs); 6440 6441 return BuildBinOp(S, TokLoc, Opc, lhs, rhs); 6442} 6443 6444Action::OwningExprResult Sema::BuildBinOp(Scope *S, SourceLocation OpLoc, 6445 BinaryOperator::Opcode Opc, 6446 Expr *lhs, Expr *rhs) { 6447 if (getLangOptions().CPlusPlus && 6448 (lhs->getType()->isOverloadableType() || 6449 rhs->getType()->isOverloadableType())) { 6450 // Find all of the overloaded operators visible from this 6451 // point. We perform both an operator-name lookup from the local 6452 // scope and an argument-dependent lookup based on the types of 6453 // the arguments. 6454 UnresolvedSet<16> Functions; 6455 OverloadedOperatorKind OverOp = BinaryOperator::getOverloadedOperator(Opc); 6456 if (S && OverOp != OO_None) 6457 LookupOverloadedOperatorName(OverOp, S, lhs->getType(), rhs->getType(), 6458 Functions); 6459 6460 // Build the (potentially-overloaded, potentially-dependent) 6461 // binary operation. 6462 return CreateOverloadedBinOp(OpLoc, Opc, Functions, lhs, rhs); 6463 } 6464 6465 // Build a built-in binary operation. 6466 return CreateBuiltinBinOp(OpLoc, Opc, lhs, rhs); 6467} 6468 6469Action::OwningExprResult Sema::CreateBuiltinUnaryOp(SourceLocation OpLoc, 6470 unsigned OpcIn, 6471 ExprArg InputArg) { 6472 UnaryOperator::Opcode Opc = static_cast<UnaryOperator::Opcode>(OpcIn); 6473 6474 // FIXME: Input is modified below, but InputArg is not updated appropriately. 6475 Expr *Input = (Expr *)InputArg.get(); 6476 QualType resultType; 6477 switch (Opc) { 6478 case UnaryOperator::OffsetOf: 6479 assert(false && "Invalid unary operator"); 6480 break; 6481 6482 case UnaryOperator::PreInc: 6483 case UnaryOperator::PreDec: 6484 case UnaryOperator::PostInc: 6485 case UnaryOperator::PostDec: 6486 resultType = CheckIncrementDecrementOperand(Input, OpLoc, 6487 Opc == UnaryOperator::PreInc || 6488 Opc == UnaryOperator::PostInc, 6489 Opc == UnaryOperator::PreInc || 6490 Opc == UnaryOperator::PreDec); 6491 break; 6492 case UnaryOperator::AddrOf: 6493 resultType = CheckAddressOfOperand(Input, OpLoc); 6494 break; 6495 case UnaryOperator::Deref: 6496 DefaultFunctionArrayLvalueConversion(Input); 6497 resultType = CheckIndirectionOperand(Input, OpLoc); 6498 break; 6499 case UnaryOperator::Plus: 6500 case UnaryOperator::Minus: 6501 UsualUnaryConversions(Input); 6502 resultType = Input->getType(); 6503 if (resultType->isDependentType()) 6504 break; 6505 if (resultType->isArithmeticType()) // C99 6.5.3.3p1 6506 break; 6507 else if (getLangOptions().CPlusPlus && // C++ [expr.unary.op]p6-7 6508 resultType->isEnumeralType()) 6509 break; 6510 else if (getLangOptions().CPlusPlus && // C++ [expr.unary.op]p6 6511 Opc == UnaryOperator::Plus && 6512 resultType->isPointerType()) 6513 break; 6514 6515 return ExprError(Diag(OpLoc, diag::err_typecheck_unary_expr) 6516 << resultType << Input->getSourceRange()); 6517 case UnaryOperator::Not: // bitwise complement 6518 UsualUnaryConversions(Input); 6519 resultType = Input->getType(); 6520 if (resultType->isDependentType()) 6521 break; 6522 // C99 6.5.3.3p1. We allow complex int and float as a GCC extension. 6523 if (resultType->isComplexType() || resultType->isComplexIntegerType()) 6524 // C99 does not support '~' for complex conjugation. 6525 Diag(OpLoc, diag::ext_integer_complement_complex) 6526 << resultType << Input->getSourceRange(); 6527 else if (!resultType->isIntegerType()) 6528 return ExprError(Diag(OpLoc, diag::err_typecheck_unary_expr) 6529 << resultType << Input->getSourceRange()); 6530 break; 6531 case UnaryOperator::LNot: // logical negation 6532 // Unlike +/-/~, integer promotions aren't done here (C99 6.5.3.3p5). 6533 DefaultFunctionArrayLvalueConversion(Input); 6534 resultType = Input->getType(); 6535 if (resultType->isDependentType()) 6536 break; 6537 if (!resultType->isScalarType()) // C99 6.5.3.3p1 6538 return ExprError(Diag(OpLoc, diag::err_typecheck_unary_expr) 6539 << resultType << Input->getSourceRange()); 6540 // LNot always has type int. C99 6.5.3.3p5. 6541 // In C++, it's bool. C++ 5.3.1p8 6542 resultType = getLangOptions().CPlusPlus ? Context.BoolTy : Context.IntTy; 6543 break; 6544 case UnaryOperator::Real: 6545 case UnaryOperator::Imag: 6546 resultType = CheckRealImagOperand(Input, OpLoc, Opc == UnaryOperator::Real); 6547 break; 6548 case UnaryOperator::Extension: 6549 resultType = Input->getType(); 6550 break; 6551 } 6552 if (resultType.isNull()) 6553 return ExprError(); 6554 6555 InputArg.release(); 6556 return Owned(new (Context) UnaryOperator(Input, Opc, resultType, OpLoc)); 6557} 6558 6559Action::OwningExprResult Sema::BuildUnaryOp(Scope *S, SourceLocation OpLoc, 6560 UnaryOperator::Opcode Opc, 6561 ExprArg input) { 6562 Expr *Input = (Expr*)input.get(); 6563 if (getLangOptions().CPlusPlus && Input->getType()->isOverloadableType() && 6564 Opc != UnaryOperator::Extension) { 6565 // Find all of the overloaded operators visible from this 6566 // point. We perform both an operator-name lookup from the local 6567 // scope and an argument-dependent lookup based on the types of 6568 // the arguments. 6569 UnresolvedSet<16> Functions; 6570 OverloadedOperatorKind OverOp = UnaryOperator::getOverloadedOperator(Opc); 6571 if (S && OverOp != OO_None) 6572 LookupOverloadedOperatorName(OverOp, S, Input->getType(), QualType(), 6573 Functions); 6574 6575 return CreateOverloadedUnaryOp(OpLoc, Opc, Functions, move(input)); 6576 } 6577 6578 return CreateBuiltinUnaryOp(OpLoc, Opc, move(input)); 6579} 6580 6581// Unary Operators. 'Tok' is the token for the operator. 6582Action::OwningExprResult Sema::ActOnUnaryOp(Scope *S, SourceLocation OpLoc, 6583 tok::TokenKind Op, ExprArg input) { 6584 return BuildUnaryOp(S, OpLoc, ConvertTokenKindToUnaryOpcode(Op), move(input)); 6585} 6586 6587/// ActOnAddrLabel - Parse the GNU address of label extension: "&&foo". 6588Sema::OwningExprResult Sema::ActOnAddrLabel(SourceLocation OpLoc, 6589 SourceLocation LabLoc, 6590 IdentifierInfo *LabelII) { 6591 // Look up the record for this label identifier. 6592 LabelStmt *&LabelDecl = getLabelMap()[LabelII]; 6593 6594 // If we haven't seen this label yet, create a forward reference. It 6595 // will be validated and/or cleaned up in ActOnFinishFunctionBody. 6596 if (LabelDecl == 0) 6597 LabelDecl = new (Context) LabelStmt(LabLoc, LabelII, 0); 6598 6599 // Create the AST node. The address of a label always has type 'void*'. 6600 return Owned(new (Context) AddrLabelExpr(OpLoc, LabLoc, LabelDecl, 6601 Context.getPointerType(Context.VoidTy))); 6602} 6603 6604Sema::OwningExprResult 6605Sema::ActOnStmtExpr(SourceLocation LPLoc, StmtArg substmt, 6606 SourceLocation RPLoc) { // "({..})" 6607 Stmt *SubStmt = static_cast<Stmt*>(substmt.get()); 6608 assert(SubStmt && isa<CompoundStmt>(SubStmt) && "Invalid action invocation!"); 6609 CompoundStmt *Compound = cast<CompoundStmt>(SubStmt); 6610 6611 bool isFileScope 6612 = (getCurFunctionOrMethodDecl() == 0) && (getCurBlock() == 0); 6613 if (isFileScope) 6614 return ExprError(Diag(LPLoc, diag::err_stmtexpr_file_scope)); 6615 6616 // FIXME: there are a variety of strange constraints to enforce here, for 6617 // example, it is not possible to goto into a stmt expression apparently. 6618 // More semantic analysis is needed. 6619 6620 // If there are sub stmts in the compound stmt, take the type of the last one 6621 // as the type of the stmtexpr. 6622 QualType Ty = Context.VoidTy; 6623 6624 if (!Compound->body_empty()) { 6625 Stmt *LastStmt = Compound->body_back(); 6626 // If LastStmt is a label, skip down through into the body. 6627 while (LabelStmt *Label = dyn_cast<LabelStmt>(LastStmt)) 6628 LastStmt = Label->getSubStmt(); 6629 6630 if (Expr *LastExpr = dyn_cast<Expr>(LastStmt)) 6631 Ty = LastExpr->getType(); 6632 } 6633 6634 // FIXME: Check that expression type is complete/non-abstract; statement 6635 // expressions are not lvalues. 6636 6637 substmt.release(); 6638 return Owned(new (Context) StmtExpr(Compound, Ty, LPLoc, RPLoc)); 6639} 6640 6641Sema::OwningExprResult Sema::BuildBuiltinOffsetOf(SourceLocation BuiltinLoc, 6642 TypeSourceInfo *TInfo, 6643 OffsetOfComponent *CompPtr, 6644 unsigned NumComponents, 6645 SourceLocation RParenLoc) { 6646 QualType ArgTy = TInfo->getType(); 6647 bool Dependent = ArgTy->isDependentType(); 6648 SourceRange TypeRange = TInfo->getTypeLoc().getSourceRange(); 6649 6650 // We must have at least one component that refers to the type, and the first 6651 // one is known to be a field designator. Verify that the ArgTy represents 6652 // a struct/union/class. 6653 if (!Dependent && !ArgTy->isRecordType()) 6654 return ExprError(Diag(BuiltinLoc, diag::err_offsetof_record_type) 6655 << ArgTy << TypeRange); 6656 6657 // Type must be complete per C99 7.17p3 because a declaring a variable 6658 // with an incomplete type would be ill-formed. 6659 if (!Dependent 6660 && RequireCompleteType(BuiltinLoc, ArgTy, 6661 PDiag(diag::err_offsetof_incomplete_type) 6662 << TypeRange)) 6663 return ExprError(); 6664 6665 // offsetof with non-identifier designators (e.g. "offsetof(x, a.b[c])") are a 6666 // GCC extension, diagnose them. 6667 // FIXME: This diagnostic isn't actually visible because the location is in 6668 // a system header! 6669 if (NumComponents != 1) 6670 Diag(BuiltinLoc, diag::ext_offsetof_extended_field_designator) 6671 << SourceRange(CompPtr[1].LocStart, CompPtr[NumComponents-1].LocEnd); 6672 6673 bool DidWarnAboutNonPOD = false; 6674 QualType CurrentType = ArgTy; 6675 typedef OffsetOfExpr::OffsetOfNode OffsetOfNode; 6676 llvm::SmallVector<OffsetOfNode, 4> Comps; 6677 llvm::SmallVector<Expr*, 4> Exprs; 6678 for (unsigned i = 0; i != NumComponents; ++i) { 6679 const OffsetOfComponent &OC = CompPtr[i]; 6680 if (OC.isBrackets) { 6681 // Offset of an array sub-field. TODO: Should we allow vector elements? 6682 if (!CurrentType->isDependentType()) { 6683 const ArrayType *AT = Context.getAsArrayType(CurrentType); 6684 if(!AT) 6685 return ExprError(Diag(OC.LocEnd, diag::err_offsetof_array_type) 6686 << CurrentType); 6687 CurrentType = AT->getElementType(); 6688 } else 6689 CurrentType = Context.DependentTy; 6690 6691 // The expression must be an integral expression. 6692 // FIXME: An integral constant expression? 6693 Expr *Idx = static_cast<Expr*>(OC.U.E); 6694 if (!Idx->isTypeDependent() && !Idx->isValueDependent() && 6695 !Idx->getType()->isIntegerType()) 6696 return ExprError(Diag(Idx->getLocStart(), 6697 diag::err_typecheck_subscript_not_integer) 6698 << Idx->getSourceRange()); 6699 6700 // Record this array index. 6701 Comps.push_back(OffsetOfNode(OC.LocStart, Exprs.size(), OC.LocEnd)); 6702 Exprs.push_back(Idx); 6703 continue; 6704 } 6705 6706 // Offset of a field. 6707 if (CurrentType->isDependentType()) { 6708 // We have the offset of a field, but we can't look into the dependent 6709 // type. Just record the identifier of the field. 6710 Comps.push_back(OffsetOfNode(OC.LocStart, OC.U.IdentInfo, OC.LocEnd)); 6711 CurrentType = Context.DependentTy; 6712 continue; 6713 } 6714 6715 // We need to have a complete type to look into. 6716 if (RequireCompleteType(OC.LocStart, CurrentType, 6717 diag::err_offsetof_incomplete_type)) 6718 return ExprError(); 6719 6720 // Look for the designated field. 6721 const RecordType *RC = CurrentType->getAs<RecordType>(); 6722 if (!RC) 6723 return ExprError(Diag(OC.LocEnd, diag::err_offsetof_record_type) 6724 << CurrentType); 6725 RecordDecl *RD = RC->getDecl(); 6726 6727 // C++ [lib.support.types]p5: 6728 // The macro offsetof accepts a restricted set of type arguments in this 6729 // International Standard. type shall be a POD structure or a POD union 6730 // (clause 9). 6731 if (CXXRecordDecl *CRD = dyn_cast<CXXRecordDecl>(RD)) { 6732 if (!CRD->isPOD() && !DidWarnAboutNonPOD && 6733 DiagRuntimeBehavior(BuiltinLoc, 6734 PDiag(diag::warn_offsetof_non_pod_type) 6735 << SourceRange(CompPtr[0].LocStart, OC.LocEnd) 6736 << CurrentType)) 6737 DidWarnAboutNonPOD = true; 6738 } 6739 6740 // Look for the field. 6741 LookupResult R(*this, OC.U.IdentInfo, OC.LocStart, LookupMemberName); 6742 LookupQualifiedName(R, RD); 6743 FieldDecl *MemberDecl = R.getAsSingle<FieldDecl>(); 6744 if (!MemberDecl) 6745 return ExprError(Diag(BuiltinLoc, diag::err_no_member) 6746 << OC.U.IdentInfo << RD << SourceRange(OC.LocStart, 6747 OC.LocEnd)); 6748 6749 // C99 7.17p3: 6750 // (If the specified member is a bit-field, the behavior is undefined.) 6751 // 6752 // We diagnose this as an error. 6753 if (MemberDecl->getBitWidth()) { 6754 Diag(OC.LocEnd, diag::err_offsetof_bitfield) 6755 << MemberDecl->getDeclName() 6756 << SourceRange(BuiltinLoc, RParenLoc); 6757 Diag(MemberDecl->getLocation(), diag::note_bitfield_decl); 6758 return ExprError(); 6759 } 6760 6761 // If the member was found in a base class, introduce OffsetOfNodes for 6762 // the base class indirections. 6763 CXXBasePaths Paths(/*FindAmbiguities=*/true, /*RecordPaths=*/true, 6764 /*DetectVirtual=*/false); 6765 if (IsDerivedFrom(CurrentType, 6766 Context.getTypeDeclType(MemberDecl->getParent()), 6767 Paths)) { 6768 CXXBasePath &Path = Paths.front(); 6769 for (CXXBasePath::iterator B = Path.begin(), BEnd = Path.end(); 6770 B != BEnd; ++B) 6771 Comps.push_back(OffsetOfNode(B->Base)); 6772 } 6773 6774 if (cast<RecordDecl>(MemberDecl->getDeclContext())-> 6775 isAnonymousStructOrUnion()) { 6776 llvm::SmallVector<FieldDecl*, 4> Path; 6777 BuildAnonymousStructUnionMemberPath(MemberDecl, Path); 6778 unsigned n = Path.size(); 6779 for (int j = n - 1; j > -1; --j) 6780 Comps.push_back(OffsetOfNode(OC.LocStart, Path[j], OC.LocEnd)); 6781 } else { 6782 Comps.push_back(OffsetOfNode(OC.LocStart, MemberDecl, OC.LocEnd)); 6783 } 6784 CurrentType = MemberDecl->getType().getNonReferenceType(); 6785 } 6786 6787 return Owned(OffsetOfExpr::Create(Context, Context.getSizeType(), BuiltinLoc, 6788 TInfo, Comps.data(), Comps.size(), 6789 Exprs.data(), Exprs.size(), RParenLoc)); 6790} 6791 6792Sema::OwningExprResult Sema::ActOnBuiltinOffsetOf(Scope *S, 6793 SourceLocation BuiltinLoc, 6794 SourceLocation TypeLoc, 6795 TypeTy *argty, 6796 OffsetOfComponent *CompPtr, 6797 unsigned NumComponents, 6798 SourceLocation RPLoc) { 6799 6800 TypeSourceInfo *ArgTInfo; 6801 QualType ArgTy = GetTypeFromParser(argty, &ArgTInfo); 6802 if (ArgTy.isNull()) 6803 return ExprError(); 6804 6805 if (getLangOptions().CPlusPlus) { 6806 if (!ArgTInfo) 6807 ArgTInfo = Context.getTrivialTypeSourceInfo(ArgTy, TypeLoc); 6808 6809 return BuildBuiltinOffsetOf(BuiltinLoc, ArgTInfo, CompPtr, NumComponents, 6810 RPLoc); 6811 } 6812 6813 // FIXME: The code below is marked for death, once we have proper CodeGen 6814 // support for non-constant OffsetOf expressions. 6815 6816 bool Dependent = ArgTy->isDependentType(); 6817 6818 // We must have at least one component that refers to the type, and the first 6819 // one is known to be a field designator. Verify that the ArgTy represents 6820 // a struct/union/class. 6821 if (!Dependent && !ArgTy->isRecordType()) 6822 return ExprError(Diag(TypeLoc, diag::err_offsetof_record_type) << ArgTy); 6823 6824 // FIXME: Type must be complete per C99 7.17p3 because a declaring a variable 6825 // with an incomplete type would be illegal. 6826 6827 // Otherwise, create a null pointer as the base, and iteratively process 6828 // the offsetof designators. 6829 QualType ArgTyPtr = Context.getPointerType(ArgTy); 6830 Expr* Res = new (Context) ImplicitValueInitExpr(ArgTyPtr); 6831 Res = new (Context) UnaryOperator(Res, UnaryOperator::Deref, 6832 ArgTy, SourceLocation()); 6833 6834 // offsetof with non-identifier designators (e.g. "offsetof(x, a.b[c])") are a 6835 // GCC extension, diagnose them. 6836 // FIXME: This diagnostic isn't actually visible because the location is in 6837 // a system header! 6838 if (NumComponents != 1) 6839 Diag(BuiltinLoc, diag::ext_offsetof_extended_field_designator) 6840 << SourceRange(CompPtr[1].LocStart, CompPtr[NumComponents-1].LocEnd); 6841 6842 if (!Dependent) { 6843 bool DidWarnAboutNonPOD = false; 6844 6845 if (RequireCompleteType(TypeLoc, Res->getType(), 6846 diag::err_offsetof_incomplete_type)) 6847 return ExprError(); 6848 6849 // FIXME: Dependent case loses a lot of information here. And probably 6850 // leaks like a sieve. 6851 for (unsigned i = 0; i != NumComponents; ++i) { 6852 const OffsetOfComponent &OC = CompPtr[i]; 6853 if (OC.isBrackets) { 6854 // Offset of an array sub-field. TODO: Should we allow vector elements? 6855 const ArrayType *AT = Context.getAsArrayType(Res->getType()); 6856 if (!AT) { 6857 Res->Destroy(Context); 6858 return ExprError(Diag(OC.LocEnd, diag::err_offsetof_array_type) 6859 << Res->getType()); 6860 } 6861 6862 // FIXME: C++: Verify that operator[] isn't overloaded. 6863 6864 // Promote the array so it looks more like a normal array subscript 6865 // expression. 6866 DefaultFunctionArrayLvalueConversion(Res); 6867 6868 // C99 6.5.2.1p1 6869 Expr *Idx = static_cast<Expr*>(OC.U.E); 6870 // FIXME: Leaks Res 6871 if (!Idx->isTypeDependent() && !Idx->getType()->isIntegerType()) 6872 return ExprError(Diag(Idx->getLocStart(), 6873 diag::err_typecheck_subscript_not_integer) 6874 << Idx->getSourceRange()); 6875 6876 Res = new (Context) ArraySubscriptExpr(Res, Idx, AT->getElementType(), 6877 OC.LocEnd); 6878 continue; 6879 } 6880 6881 const RecordType *RC = Res->getType()->getAs<RecordType>(); 6882 if (!RC) { 6883 Res->Destroy(Context); 6884 return ExprError(Diag(OC.LocEnd, diag::err_offsetof_record_type) 6885 << Res->getType()); 6886 } 6887 6888 // Get the decl corresponding to this. 6889 RecordDecl *RD = RC->getDecl(); 6890 if (CXXRecordDecl *CRD = dyn_cast<CXXRecordDecl>(RD)) { 6891 if (!CRD->isPOD() && !DidWarnAboutNonPOD && 6892 DiagRuntimeBehavior(BuiltinLoc, 6893 PDiag(diag::warn_offsetof_non_pod_type) 6894 << SourceRange(CompPtr[0].LocStart, OC.LocEnd) 6895 << Res->getType())) 6896 DidWarnAboutNonPOD = true; 6897 } 6898 6899 LookupResult R(*this, OC.U.IdentInfo, OC.LocStart, LookupMemberName); 6900 LookupQualifiedName(R, RD); 6901 6902 FieldDecl *MemberDecl = R.getAsSingle<FieldDecl>(); 6903 // FIXME: Leaks Res 6904 if (!MemberDecl) 6905 return ExprError(Diag(BuiltinLoc, diag::err_no_member) 6906 << OC.U.IdentInfo << RD << SourceRange(OC.LocStart, OC.LocEnd)); 6907 6908 // C99 7.17p3: 6909 // (If the specified member is a bit-field, the behavior is undefined.) 6910 // 6911 // We diagnose this as an error. 6912 if (MemberDecl->getBitWidth()) { 6913 Diag(OC.LocEnd, diag::err_offsetof_bitfield) 6914 << MemberDecl->getDeclName() 6915 << SourceRange(BuiltinLoc, RPLoc); 6916 Diag(MemberDecl->getLocation(), diag::note_bitfield_decl); 6917 return ExprError(); 6918 } 6919 6920 // FIXME: C++: Verify that MemberDecl isn't a static field. 6921 // FIXME: Verify that MemberDecl isn't a bitfield. 6922 if (cast<RecordDecl>(MemberDecl->getDeclContext())->isAnonymousStructOrUnion()) { 6923 Res = BuildAnonymousStructUnionMemberReference( 6924 OC.LocEnd, MemberDecl, Res, OC.LocEnd).takeAs<Expr>(); 6925 } else { 6926 PerformObjectMemberConversion(Res, /*Qualifier=*/0, 6927 *R.begin(), MemberDecl); 6928 // MemberDecl->getType() doesn't get the right qualifiers, but it 6929 // doesn't matter here. 6930 Res = new (Context) MemberExpr(Res, false, MemberDecl, OC.LocEnd, 6931 MemberDecl->getType().getNonReferenceType()); 6932 } 6933 } 6934 } 6935 6936 return Owned(new (Context) UnaryOperator(Res, UnaryOperator::OffsetOf, 6937 Context.getSizeType(), BuiltinLoc)); 6938} 6939 6940 6941Sema::OwningExprResult Sema::ActOnTypesCompatibleExpr(SourceLocation BuiltinLoc, 6942 TypeTy *arg1,TypeTy *arg2, 6943 SourceLocation RPLoc) { 6944 // FIXME: Preserve type source info. 6945 QualType argT1 = GetTypeFromParser(arg1); 6946 QualType argT2 = GetTypeFromParser(arg2); 6947 6948 assert((!argT1.isNull() && !argT2.isNull()) && "Missing type argument(s)"); 6949 6950 if (getLangOptions().CPlusPlus) { 6951 Diag(BuiltinLoc, diag::err_types_compatible_p_in_cplusplus) 6952 << SourceRange(BuiltinLoc, RPLoc); 6953 return ExprError(); 6954 } 6955 6956 return Owned(new (Context) TypesCompatibleExpr(Context.IntTy, BuiltinLoc, 6957 argT1, argT2, RPLoc)); 6958} 6959 6960Sema::OwningExprResult Sema::ActOnChooseExpr(SourceLocation BuiltinLoc, 6961 ExprArg cond, 6962 ExprArg expr1, ExprArg expr2, 6963 SourceLocation RPLoc) { 6964 Expr *CondExpr = static_cast<Expr*>(cond.get()); 6965 Expr *LHSExpr = static_cast<Expr*>(expr1.get()); 6966 Expr *RHSExpr = static_cast<Expr*>(expr2.get()); 6967 6968 assert((CondExpr && LHSExpr && RHSExpr) && "Missing type argument(s)"); 6969 6970 QualType resType; 6971 bool ValueDependent = false; 6972 if (CondExpr->isTypeDependent() || CondExpr->isValueDependent()) { 6973 resType = Context.DependentTy; 6974 ValueDependent = true; 6975 } else { 6976 // The conditional expression is required to be a constant expression. 6977 llvm::APSInt condEval(32); 6978 SourceLocation ExpLoc; 6979 if (!CondExpr->isIntegerConstantExpr(condEval, Context, &ExpLoc)) 6980 return ExprError(Diag(ExpLoc, 6981 diag::err_typecheck_choose_expr_requires_constant) 6982 << CondExpr->getSourceRange()); 6983 6984 // If the condition is > zero, then the AST type is the same as the LSHExpr. 6985 resType = condEval.getZExtValue() ? LHSExpr->getType() : RHSExpr->getType(); 6986 ValueDependent = condEval.getZExtValue() ? LHSExpr->isValueDependent() 6987 : RHSExpr->isValueDependent(); 6988 } 6989 6990 cond.release(); expr1.release(); expr2.release(); 6991 return Owned(new (Context) ChooseExpr(BuiltinLoc, CondExpr, LHSExpr, RHSExpr, 6992 resType, RPLoc, 6993 resType->isDependentType(), 6994 ValueDependent)); 6995} 6996 6997//===----------------------------------------------------------------------===// 6998// Clang Extensions. 6999//===----------------------------------------------------------------------===// 7000 7001/// ActOnBlockStart - This callback is invoked when a block literal is started. 7002void Sema::ActOnBlockStart(SourceLocation CaretLoc, Scope *BlockScope) { 7003 BlockDecl *Block = BlockDecl::Create(Context, CurContext, CaretLoc); 7004 PushBlockScope(BlockScope, Block); 7005 CurContext->addDecl(Block); 7006 PushDeclContext(BlockScope, Block); 7007} 7008 7009void Sema::ActOnBlockArguments(Declarator &ParamInfo, Scope *CurScope) { 7010 assert(ParamInfo.getIdentifier()==0 && "block-id should have no identifier!"); 7011 BlockScopeInfo *CurBlock = getCurBlock(); 7012 7013 if (ParamInfo.getNumTypeObjects() == 0 7014 || ParamInfo.getTypeObject(0).Kind != DeclaratorChunk::Function) { 7015 ProcessDeclAttributes(CurScope, CurBlock->TheDecl, ParamInfo); 7016 QualType T = GetTypeForDeclarator(ParamInfo, CurScope); 7017 7018 if (T->isArrayType()) { 7019 Diag(ParamInfo.getSourceRange().getBegin(), 7020 diag::err_block_returns_array); 7021 return; 7022 } 7023 7024 // The parameter list is optional, if there was none, assume (). 7025 if (!T->isFunctionType()) 7026 T = Context.getFunctionType(T, 0, 0, false, 0, false, false, 0, 0, 7027 FunctionType::ExtInfo()); 7028 7029 CurBlock->hasPrototype = true; 7030 CurBlock->isVariadic = false; 7031 // Check for a valid sentinel attribute on this block. 7032 if (CurBlock->TheDecl->getAttr<SentinelAttr>()) { 7033 Diag(ParamInfo.getAttributes()->getLoc(), 7034 diag::warn_attribute_sentinel_not_variadic) << 1; 7035 // FIXME: remove the attribute. 7036 } 7037 QualType RetTy = T.getTypePtr()->getAs<FunctionType>()->getResultType(); 7038 7039 // Do not allow returning a objc interface by-value. 7040 if (RetTy->isObjCObjectType()) { 7041 Diag(ParamInfo.getSourceRange().getBegin(), 7042 diag::err_object_cannot_be_passed_returned_by_value) << 0 << RetTy; 7043 return; 7044 } 7045 7046 CurBlock->ReturnType = RetTy; 7047 return; 7048 } 7049 7050 // Analyze arguments to block. 7051 assert(ParamInfo.getTypeObject(0).Kind == DeclaratorChunk::Function && 7052 "Not a function declarator!"); 7053 DeclaratorChunk::FunctionTypeInfo &FTI = ParamInfo.getTypeObject(0).Fun; 7054 7055 CurBlock->hasPrototype = FTI.hasPrototype; 7056 CurBlock->isVariadic = true; 7057 7058 // Check for C99 6.7.5.3p10 - foo(void) is a non-varargs function that takes 7059 // no arguments, not a function that takes a single void argument. 7060 if (FTI.hasPrototype && 7061 FTI.NumArgs == 1 && !FTI.isVariadic && FTI.ArgInfo[0].Ident == 0 && 7062 (!FTI.ArgInfo[0].Param.getAs<ParmVarDecl>()->getType().getCVRQualifiers()&& 7063 FTI.ArgInfo[0].Param.getAs<ParmVarDecl>()->getType()->isVoidType())) { 7064 // empty arg list, don't push any params. 7065 CurBlock->isVariadic = false; 7066 } else if (FTI.hasPrototype) { 7067 for (unsigned i = 0, e = FTI.NumArgs; i != e; ++i) { 7068 ParmVarDecl *Param = FTI.ArgInfo[i].Param.getAs<ParmVarDecl>(); 7069 if (Param->getIdentifier() == 0 && 7070 !Param->isImplicit() && 7071 !Param->isInvalidDecl() && 7072 !getLangOptions().CPlusPlus) 7073 Diag(Param->getLocation(), diag::err_parameter_name_omitted); 7074 CurBlock->Params.push_back(Param); 7075 } 7076 CurBlock->isVariadic = FTI.isVariadic; 7077 } 7078 CurBlock->TheDecl->setParams(CurBlock->Params.data(), 7079 CurBlock->Params.size()); 7080 CurBlock->TheDecl->setIsVariadic(CurBlock->isVariadic); 7081 ProcessDeclAttributes(CurScope, CurBlock->TheDecl, ParamInfo); 7082 7083 bool ShouldCheckShadow = 7084 Diags.getDiagnosticLevel(diag::warn_decl_shadow) != Diagnostic::Ignored; 7085 7086 for (BlockDecl::param_iterator AI = CurBlock->TheDecl->param_begin(), 7087 E = CurBlock->TheDecl->param_end(); AI != E; ++AI) { 7088 (*AI)->setOwningFunction(CurBlock->TheDecl); 7089 7090 // If this has an identifier, add it to the scope stack. 7091 if ((*AI)->getIdentifier()) { 7092 if (ShouldCheckShadow) 7093 CheckShadow(CurBlock->TheScope, *AI); 7094 7095 PushOnScopeChains(*AI, CurBlock->TheScope); 7096 } 7097 } 7098 7099 // Check for a valid sentinel attribute on this block. 7100 if (!CurBlock->isVariadic && 7101 CurBlock->TheDecl->getAttr<SentinelAttr>()) { 7102 Diag(ParamInfo.getAttributes()->getLoc(), 7103 diag::warn_attribute_sentinel_not_variadic) << 1; 7104 // FIXME: remove the attribute. 7105 } 7106 7107 // Analyze the return type. 7108 QualType T = GetTypeForDeclarator(ParamInfo, CurScope); 7109 QualType RetTy = T->getAs<FunctionType>()->getResultType(); 7110 7111 // Do not 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 } else if (!RetTy->isDependentType()) 7116 CurBlock->ReturnType = RetTy; 7117} 7118 7119/// ActOnBlockError - If there is an error parsing a block, this callback 7120/// is invoked to pop the information about the block from the action impl. 7121void Sema::ActOnBlockError(SourceLocation CaretLoc, Scope *CurScope) { 7122 // Pop off CurBlock, handle nested blocks. 7123 PopDeclContext(); 7124 PopFunctionOrBlockScope(); 7125 // FIXME: Delete the ParmVarDecl objects as well??? 7126} 7127 7128/// ActOnBlockStmtExpr - This is called when the body of a block statement 7129/// literal was successfully completed. ^(int x){...} 7130Sema::OwningExprResult Sema::ActOnBlockStmtExpr(SourceLocation CaretLoc, 7131 StmtArg body, Scope *CurScope) { 7132 // If blocks are disabled, emit an error. 7133 if (!LangOpts.Blocks) 7134 Diag(CaretLoc, diag::err_blocks_disable); 7135 7136 BlockScopeInfo *BSI = cast<BlockScopeInfo>(FunctionScopes.back()); 7137 7138 PopDeclContext(); 7139 7140 QualType RetTy = Context.VoidTy; 7141 if (!BSI->ReturnType.isNull()) 7142 RetTy = BSI->ReturnType; 7143 7144 llvm::SmallVector<QualType, 8> ArgTypes; 7145 for (unsigned i = 0, e = BSI->Params.size(); i != e; ++i) 7146 ArgTypes.push_back(BSI->Params[i]->getType()); 7147 7148 bool NoReturn = BSI->TheDecl->getAttr<NoReturnAttr>(); 7149 QualType BlockTy; 7150 if (!BSI->hasPrototype) 7151 BlockTy = Context.getFunctionType(RetTy, 0, 0, false, 0, false, false, 0, 0, 7152 FunctionType::ExtInfo(NoReturn, 0, CC_Default)); 7153 else 7154 BlockTy = Context.getFunctionType(RetTy, ArgTypes.data(), ArgTypes.size(), 7155 BSI->isVariadic, 0, false, false, 0, 0, 7156 FunctionType::ExtInfo(NoReturn, 0, CC_Default)); 7157 7158 // FIXME: Check that return/parameter types are complete/non-abstract 7159 DiagnoseUnusedParameters(BSI->Params.begin(), BSI->Params.end()); 7160 BlockTy = Context.getBlockPointerType(BlockTy); 7161 7162 // If needed, diagnose invalid gotos and switches in the block. 7163 if (FunctionNeedsScopeChecking() && !hasAnyErrorsInThisFunction()) 7164 DiagnoseInvalidJumps(static_cast<CompoundStmt*>(body.get())); 7165 7166 BSI->TheDecl->setBody(body.takeAs<CompoundStmt>()); 7167 7168 bool Good = true; 7169 // Check goto/label use. 7170 for (llvm::DenseMap<IdentifierInfo*, LabelStmt*>::iterator 7171 I = BSI->LabelMap.begin(), E = BSI->LabelMap.end(); I != E; ++I) { 7172 LabelStmt *L = I->second; 7173 7174 // Verify that we have no forward references left. If so, there was a goto 7175 // or address of a label taken, but no definition of it. 7176 if (L->getSubStmt() != 0) 7177 continue; 7178 7179 // Emit error. 7180 Diag(L->getIdentLoc(), diag::err_undeclared_label_use) << L->getName(); 7181 Good = false; 7182 } 7183 if (!Good) { 7184 PopFunctionOrBlockScope(); 7185 return ExprError(); 7186 } 7187 7188 // Issue any analysis-based warnings. 7189 const sema::AnalysisBasedWarnings::Policy &WP = 7190 AnalysisWarnings.getDefaultPolicy(); 7191 AnalysisWarnings.IssueWarnings(WP, BSI->TheDecl, BlockTy); 7192 7193 Expr *Result = new (Context) BlockExpr(BSI->TheDecl, BlockTy, 7194 BSI->hasBlockDeclRefExprs); 7195 PopFunctionOrBlockScope(); 7196 return Owned(Result); 7197} 7198 7199Sema::OwningExprResult Sema::ActOnVAArg(SourceLocation BuiltinLoc, 7200 ExprArg expr, TypeTy *type, 7201 SourceLocation RPLoc) { 7202 QualType T = GetTypeFromParser(type); 7203 Expr *E = static_cast<Expr*>(expr.get()); 7204 Expr *OrigExpr = E; 7205 7206 InitBuiltinVaListType(); 7207 7208 // Get the va_list type 7209 QualType VaListType = Context.getBuiltinVaListType(); 7210 if (VaListType->isArrayType()) { 7211 // Deal with implicit array decay; for example, on x86-64, 7212 // va_list is an array, but it's supposed to decay to 7213 // a pointer for va_arg. 7214 VaListType = Context.getArrayDecayedType(VaListType); 7215 // Make sure the input expression also decays appropriately. 7216 UsualUnaryConversions(E); 7217 } else { 7218 // Otherwise, the va_list argument must be an l-value because 7219 // it is modified by va_arg. 7220 if (!E->isTypeDependent() && 7221 CheckForModifiableLvalue(E, BuiltinLoc, *this)) 7222 return ExprError(); 7223 } 7224 7225 if (!E->isTypeDependent() && 7226 !Context.hasSameType(VaListType, E->getType())) { 7227 return ExprError(Diag(E->getLocStart(), 7228 diag::err_first_argument_to_va_arg_not_of_type_va_list) 7229 << OrigExpr->getType() << E->getSourceRange()); 7230 } 7231 7232 // FIXME: Check that type is complete/non-abstract 7233 // FIXME: Warn if a non-POD type is passed in. 7234 7235 expr.release(); 7236 return Owned(new (Context) VAArgExpr(BuiltinLoc, E, T.getNonReferenceType(), 7237 RPLoc)); 7238} 7239 7240Sema::OwningExprResult Sema::ActOnGNUNullExpr(SourceLocation TokenLoc) { 7241 // The type of __null will be int or long, depending on the size of 7242 // pointers on the target. 7243 QualType Ty; 7244 if (Context.Target.getPointerWidth(0) == Context.Target.getIntWidth()) 7245 Ty = Context.IntTy; 7246 else 7247 Ty = Context.LongTy; 7248 7249 return Owned(new (Context) GNUNullExpr(Ty, TokenLoc)); 7250} 7251 7252static void MakeObjCStringLiteralFixItHint(Sema& SemaRef, QualType DstType, 7253 Expr *SrcExpr, FixItHint &Hint) { 7254 if (!SemaRef.getLangOptions().ObjC1) 7255 return; 7256 7257 const ObjCObjectPointerType *PT = DstType->getAs<ObjCObjectPointerType>(); 7258 if (!PT) 7259 return; 7260 7261 // Check if the destination is of type 'id'. 7262 if (!PT->isObjCIdType()) { 7263 // Check if the destination is the 'NSString' interface. 7264 const ObjCInterfaceDecl *ID = PT->getInterfaceDecl(); 7265 if (!ID || !ID->getIdentifier()->isStr("NSString")) 7266 return; 7267 } 7268 7269 // Strip off any parens and casts. 7270 StringLiteral *SL = dyn_cast<StringLiteral>(SrcExpr->IgnoreParenCasts()); 7271 if (!SL || SL->isWide()) 7272 return; 7273 7274 Hint = FixItHint::CreateInsertion(SL->getLocStart(), "@"); 7275} 7276 7277bool Sema::DiagnoseAssignmentResult(AssignConvertType ConvTy, 7278 SourceLocation Loc, 7279 QualType DstType, QualType SrcType, 7280 Expr *SrcExpr, AssignmentAction Action, 7281 bool *Complained) { 7282 if (Complained) 7283 *Complained = false; 7284 7285 // Decode the result (notice that AST's are still created for extensions). 7286 bool isInvalid = false; 7287 unsigned DiagKind; 7288 FixItHint Hint; 7289 7290 switch (ConvTy) { 7291 default: assert(0 && "Unknown conversion type"); 7292 case Compatible: return false; 7293 case PointerToInt: 7294 DiagKind = diag::ext_typecheck_convert_pointer_int; 7295 break; 7296 case IntToPointer: 7297 DiagKind = diag::ext_typecheck_convert_int_pointer; 7298 break; 7299 case IncompatiblePointer: 7300 MakeObjCStringLiteralFixItHint(*this, DstType, SrcExpr, Hint); 7301 DiagKind = diag::ext_typecheck_convert_incompatible_pointer; 7302 break; 7303 case IncompatiblePointerSign: 7304 DiagKind = diag::ext_typecheck_convert_incompatible_pointer_sign; 7305 break; 7306 case FunctionVoidPointer: 7307 DiagKind = diag::ext_typecheck_convert_pointer_void_func; 7308 break; 7309 case CompatiblePointerDiscardsQualifiers: 7310 // If the qualifiers lost were because we were applying the 7311 // (deprecated) C++ conversion from a string literal to a char* 7312 // (or wchar_t*), then there was no error (C++ 4.2p2). FIXME: 7313 // Ideally, this check would be performed in 7314 // CheckPointerTypesForAssignment. However, that would require a 7315 // bit of refactoring (so that the second argument is an 7316 // expression, rather than a type), which should be done as part 7317 // of a larger effort to fix CheckPointerTypesForAssignment for 7318 // C++ semantics. 7319 if (getLangOptions().CPlusPlus && 7320 IsStringLiteralToNonConstPointerConversion(SrcExpr, DstType)) 7321 return false; 7322 DiagKind = diag::ext_typecheck_convert_discards_qualifiers; 7323 break; 7324 case IncompatibleNestedPointerQualifiers: 7325 DiagKind = diag::ext_nested_pointer_qualifier_mismatch; 7326 break; 7327 case IntToBlockPointer: 7328 DiagKind = diag::err_int_to_block_pointer; 7329 break; 7330 case IncompatibleBlockPointer: 7331 DiagKind = diag::err_typecheck_convert_incompatible_block_pointer; 7332 break; 7333 case IncompatibleObjCQualifiedId: 7334 // FIXME: Diagnose the problem in ObjCQualifiedIdTypesAreCompatible, since 7335 // it can give a more specific diagnostic. 7336 DiagKind = diag::warn_incompatible_qualified_id; 7337 break; 7338 case IncompatibleVectors: 7339 DiagKind = diag::warn_incompatible_vectors; 7340 break; 7341 case Incompatible: 7342 DiagKind = diag::err_typecheck_convert_incompatible; 7343 isInvalid = true; 7344 break; 7345 } 7346 7347 QualType FirstType, SecondType; 7348 switch (Action) { 7349 case AA_Assigning: 7350 case AA_Initializing: 7351 // The destination type comes first. 7352 FirstType = DstType; 7353 SecondType = SrcType; 7354 break; 7355 7356 case AA_Returning: 7357 case AA_Passing: 7358 case AA_Converting: 7359 case AA_Sending: 7360 case AA_Casting: 7361 // The source type comes first. 7362 FirstType = SrcType; 7363 SecondType = DstType; 7364 break; 7365 } 7366 7367 Diag(Loc, DiagKind) << FirstType << SecondType << Action 7368 << SrcExpr->getSourceRange() << Hint; 7369 if (Complained) 7370 *Complained = true; 7371 return isInvalid; 7372} 7373 7374bool Sema::VerifyIntegerConstantExpression(const Expr *E, llvm::APSInt *Result){ 7375 llvm::APSInt ICEResult; 7376 if (E->isIntegerConstantExpr(ICEResult, Context)) { 7377 if (Result) 7378 *Result = ICEResult; 7379 return false; 7380 } 7381 7382 Expr::EvalResult EvalResult; 7383 7384 if (!E->Evaluate(EvalResult, Context) || !EvalResult.Val.isInt() || 7385 EvalResult.HasSideEffects) { 7386 Diag(E->getExprLoc(), diag::err_expr_not_ice) << E->getSourceRange(); 7387 7388 if (EvalResult.Diag) { 7389 // We only show the note if it's not the usual "invalid subexpression" 7390 // or if it's actually in a subexpression. 7391 if (EvalResult.Diag != diag::note_invalid_subexpr_in_ice || 7392 E->IgnoreParens() != EvalResult.DiagExpr->IgnoreParens()) 7393 Diag(EvalResult.DiagLoc, EvalResult.Diag); 7394 } 7395 7396 return true; 7397 } 7398 7399 Diag(E->getExprLoc(), diag::ext_expr_not_ice) << 7400 E->getSourceRange(); 7401 7402 if (EvalResult.Diag && 7403 Diags.getDiagnosticLevel(diag::ext_expr_not_ice) != Diagnostic::Ignored) 7404 Diag(EvalResult.DiagLoc, EvalResult.Diag); 7405 7406 if (Result) 7407 *Result = EvalResult.Val.getInt(); 7408 return false; 7409} 7410 7411void 7412Sema::PushExpressionEvaluationContext(ExpressionEvaluationContext NewContext) { 7413 ExprEvalContexts.push_back( 7414 ExpressionEvaluationContextRecord(NewContext, ExprTemporaries.size())); 7415} 7416 7417void 7418Sema::PopExpressionEvaluationContext() { 7419 // Pop the current expression evaluation context off the stack. 7420 ExpressionEvaluationContextRecord Rec = ExprEvalContexts.back(); 7421 ExprEvalContexts.pop_back(); 7422 7423 if (Rec.Context == PotentiallyPotentiallyEvaluated) { 7424 if (Rec.PotentiallyReferenced) { 7425 // Mark any remaining declarations in the current position of the stack 7426 // as "referenced". If they were not meant to be referenced, semantic 7427 // analysis would have eliminated them (e.g., in ActOnCXXTypeId). 7428 for (PotentiallyReferencedDecls::iterator 7429 I = Rec.PotentiallyReferenced->begin(), 7430 IEnd = Rec.PotentiallyReferenced->end(); 7431 I != IEnd; ++I) 7432 MarkDeclarationReferenced(I->first, I->second); 7433 } 7434 7435 if (Rec.PotentiallyDiagnosed) { 7436 // Emit any pending diagnostics. 7437 for (PotentiallyEmittedDiagnostics::iterator 7438 I = Rec.PotentiallyDiagnosed->begin(), 7439 IEnd = Rec.PotentiallyDiagnosed->end(); 7440 I != IEnd; ++I) 7441 Diag(I->first, I->second); 7442 } 7443 } 7444 7445 // When are coming out of an unevaluated context, clear out any 7446 // temporaries that we may have created as part of the evaluation of 7447 // the expression in that context: they aren't relevant because they 7448 // will never be constructed. 7449 if (Rec.Context == Unevaluated && 7450 ExprTemporaries.size() > Rec.NumTemporaries) 7451 ExprTemporaries.erase(ExprTemporaries.begin() + Rec.NumTemporaries, 7452 ExprTemporaries.end()); 7453 7454 // Destroy the popped expression evaluation record. 7455 Rec.Destroy(); 7456} 7457 7458/// \brief Note that the given declaration was referenced in the source code. 7459/// 7460/// This routine should be invoke whenever a given declaration is referenced 7461/// in the source code, and where that reference occurred. If this declaration 7462/// reference means that the the declaration is used (C++ [basic.def.odr]p2, 7463/// C99 6.9p3), then the declaration will be marked as used. 7464/// 7465/// \param Loc the location where the declaration was referenced. 7466/// 7467/// \param D the declaration that has been referenced by the source code. 7468void Sema::MarkDeclarationReferenced(SourceLocation Loc, Decl *D) { 7469 assert(D && "No declaration?"); 7470 7471 if (D->isUsed()) 7472 return; 7473 7474 // Mark a parameter or variable declaration "used", regardless of whether we're in a 7475 // template or not. The reason for this is that unevaluated expressions 7476 // (e.g. (void)sizeof()) constitute a use for warning purposes (-Wunused-variables and 7477 // -Wunused-parameters) 7478 if (isa<ParmVarDecl>(D) || 7479 (isa<VarDecl>(D) && D->getDeclContext()->isFunctionOrMethod())) { 7480 D->setUsed(true); 7481 return; 7482 } 7483 7484 if (!isa<VarDecl>(D) && !isa<FunctionDecl>(D)) 7485 return; 7486 7487 // Do not mark anything as "used" within a dependent context; wait for 7488 // an instantiation. 7489 if (CurContext->isDependentContext()) 7490 return; 7491 7492 switch (ExprEvalContexts.back().Context) { 7493 case Unevaluated: 7494 // We are in an expression that is not potentially evaluated; do nothing. 7495 return; 7496 7497 case PotentiallyEvaluated: 7498 // We are in a potentially-evaluated expression, so this declaration is 7499 // "used"; handle this below. 7500 break; 7501 7502 case PotentiallyPotentiallyEvaluated: 7503 // We are in an expression that may be potentially evaluated; queue this 7504 // declaration reference until we know whether the expression is 7505 // potentially evaluated. 7506 ExprEvalContexts.back().addReferencedDecl(Loc, D); 7507 return; 7508 } 7509 7510 // Note that this declaration has been used. 7511 if (CXXConstructorDecl *Constructor = dyn_cast<CXXConstructorDecl>(D)) { 7512 unsigned TypeQuals; 7513 if (Constructor->isImplicit() && Constructor->isDefaultConstructor()) { 7514 if (!Constructor->isUsed()) 7515 DefineImplicitDefaultConstructor(Loc, Constructor); 7516 } else if (Constructor->isImplicit() && 7517 Constructor->isCopyConstructor(TypeQuals)) { 7518 if (!Constructor->isUsed()) 7519 DefineImplicitCopyConstructor(Loc, Constructor, TypeQuals); 7520 } 7521 7522 MarkVTableUsed(Loc, Constructor->getParent()); 7523 } else if (CXXDestructorDecl *Destructor = dyn_cast<CXXDestructorDecl>(D)) { 7524 if (Destructor->isImplicit() && !Destructor->isUsed()) 7525 DefineImplicitDestructor(Loc, Destructor); 7526 if (Destructor->isVirtual()) 7527 MarkVTableUsed(Loc, Destructor->getParent()); 7528 } else if (CXXMethodDecl *MethodDecl = dyn_cast<CXXMethodDecl>(D)) { 7529 if (MethodDecl->isImplicit() && MethodDecl->isOverloadedOperator() && 7530 MethodDecl->getOverloadedOperator() == OO_Equal) { 7531 if (!MethodDecl->isUsed()) 7532 DefineImplicitCopyAssignment(Loc, MethodDecl); 7533 } else if (MethodDecl->isVirtual()) 7534 MarkVTableUsed(Loc, MethodDecl->getParent()); 7535 } 7536 if (FunctionDecl *Function = dyn_cast<FunctionDecl>(D)) { 7537 // Implicit instantiation of function templates and member functions of 7538 // class templates. 7539 if (Function->isImplicitlyInstantiable()) { 7540 bool AlreadyInstantiated = false; 7541 if (FunctionTemplateSpecializationInfo *SpecInfo 7542 = Function->getTemplateSpecializationInfo()) { 7543 if (SpecInfo->getPointOfInstantiation().isInvalid()) 7544 SpecInfo->setPointOfInstantiation(Loc); 7545 else if (SpecInfo->getTemplateSpecializationKind() 7546 == TSK_ImplicitInstantiation) 7547 AlreadyInstantiated = true; 7548 } else if (MemberSpecializationInfo *MSInfo 7549 = Function->getMemberSpecializationInfo()) { 7550 if (MSInfo->getPointOfInstantiation().isInvalid()) 7551 MSInfo->setPointOfInstantiation(Loc); 7552 else if (MSInfo->getTemplateSpecializationKind() 7553 == TSK_ImplicitInstantiation) 7554 AlreadyInstantiated = true; 7555 } 7556 7557 if (!AlreadyInstantiated) { 7558 if (isa<CXXRecordDecl>(Function->getDeclContext()) && 7559 cast<CXXRecordDecl>(Function->getDeclContext())->isLocalClass()) 7560 PendingLocalImplicitInstantiations.push_back(std::make_pair(Function, 7561 Loc)); 7562 else 7563 PendingImplicitInstantiations.push_back(std::make_pair(Function, 7564 Loc)); 7565 } 7566 } 7567 7568 // FIXME: keep track of references to static functions 7569 Function->setUsed(true); 7570 7571 return; 7572 } 7573 7574 if (VarDecl *Var = dyn_cast<VarDecl>(D)) { 7575 // Implicit instantiation of static data members of class templates. 7576 if (Var->isStaticDataMember() && 7577 Var->getInstantiatedFromStaticDataMember()) { 7578 MemberSpecializationInfo *MSInfo = Var->getMemberSpecializationInfo(); 7579 assert(MSInfo && "Missing member specialization information?"); 7580 if (MSInfo->getPointOfInstantiation().isInvalid() && 7581 MSInfo->getTemplateSpecializationKind()== TSK_ImplicitInstantiation) { 7582 MSInfo->setPointOfInstantiation(Loc); 7583 PendingImplicitInstantiations.push_back(std::make_pair(Var, Loc)); 7584 } 7585 } 7586 7587 // FIXME: keep track of references to static data? 7588 7589 D->setUsed(true); 7590 return; 7591 } 7592} 7593 7594namespace { 7595 // Mark all of the declarations referenced 7596 // FIXME: Not fully implemented yet! We need to have a better understanding 7597 // of when we're entering 7598 class MarkReferencedDecls : public RecursiveASTVisitor<MarkReferencedDecls> { 7599 Sema &S; 7600 SourceLocation Loc; 7601 7602 public: 7603 typedef RecursiveASTVisitor<MarkReferencedDecls> Inherited; 7604 7605 MarkReferencedDecls(Sema &S, SourceLocation Loc) : S(S), Loc(Loc) { } 7606 7607 bool VisitTemplateArgument(const TemplateArgument &Arg); 7608 bool VisitRecordType(RecordType *T); 7609 }; 7610} 7611 7612bool MarkReferencedDecls::VisitTemplateArgument(const TemplateArgument &Arg) { 7613 if (Arg.getKind() == TemplateArgument::Declaration) { 7614 S.MarkDeclarationReferenced(Loc, Arg.getAsDecl()); 7615 } 7616 7617 return Inherited::VisitTemplateArgument(Arg); 7618} 7619 7620bool MarkReferencedDecls::VisitRecordType(RecordType *T) { 7621 if (ClassTemplateSpecializationDecl *Spec 7622 = dyn_cast<ClassTemplateSpecializationDecl>(T->getDecl())) { 7623 const TemplateArgumentList &Args = Spec->getTemplateArgs(); 7624 return VisitTemplateArguments(Args.getFlatArgumentList(), 7625 Args.flat_size()); 7626 } 7627 7628 return false; 7629} 7630 7631void Sema::MarkDeclarationsReferencedInType(SourceLocation Loc, QualType T) { 7632 MarkReferencedDecls Marker(*this, Loc); 7633 Marker.Visit(Context.getCanonicalType(T)); 7634} 7635 7636/// \brief Emit a diagnostic that describes an effect on the run-time behavior 7637/// of the program being compiled. 7638/// 7639/// This routine emits the given diagnostic when the code currently being 7640/// type-checked is "potentially evaluated", meaning that there is a 7641/// possibility that the code will actually be executable. Code in sizeof() 7642/// expressions, code used only during overload resolution, etc., are not 7643/// potentially evaluated. This routine will suppress such diagnostics or, 7644/// in the absolutely nutty case of potentially potentially evaluated 7645/// expressions (C++ typeid), queue the diagnostic to potentially emit it 7646/// later. 7647/// 7648/// This routine should be used for all diagnostics that describe the run-time 7649/// behavior of a program, such as passing a non-POD value through an ellipsis. 7650/// Failure to do so will likely result in spurious diagnostics or failures 7651/// during overload resolution or within sizeof/alignof/typeof/typeid. 7652bool Sema::DiagRuntimeBehavior(SourceLocation Loc, 7653 const PartialDiagnostic &PD) { 7654 switch (ExprEvalContexts.back().Context ) { 7655 case Unevaluated: 7656 // The argument will never be evaluated, so don't complain. 7657 break; 7658 7659 case PotentiallyEvaluated: 7660 Diag(Loc, PD); 7661 return true; 7662 7663 case PotentiallyPotentiallyEvaluated: 7664 ExprEvalContexts.back().addDiagnostic(Loc, PD); 7665 break; 7666 } 7667 7668 return false; 7669} 7670 7671bool Sema::CheckCallReturnType(QualType ReturnType, SourceLocation Loc, 7672 CallExpr *CE, FunctionDecl *FD) { 7673 if (ReturnType->isVoidType() || !ReturnType->isIncompleteType()) 7674 return false; 7675 7676 PartialDiagnostic Note = 7677 FD ? PDiag(diag::note_function_with_incomplete_return_type_declared_here) 7678 << FD->getDeclName() : PDiag(); 7679 SourceLocation NoteLoc = FD ? FD->getLocation() : SourceLocation(); 7680 7681 if (RequireCompleteType(Loc, ReturnType, 7682 FD ? 7683 PDiag(diag::err_call_function_incomplete_return) 7684 << CE->getSourceRange() << FD->getDeclName() : 7685 PDiag(diag::err_call_incomplete_return) 7686 << CE->getSourceRange(), 7687 std::make_pair(NoteLoc, Note))) 7688 return true; 7689 7690 return false; 7691} 7692 7693// Diagnose the common s/=/==/ typo. Note that adding parentheses 7694// will prevent this condition from triggering, which is what we want. 7695void Sema::DiagnoseAssignmentAsCondition(Expr *E) { 7696 SourceLocation Loc; 7697 7698 unsigned diagnostic = diag::warn_condition_is_assignment; 7699 7700 if (isa<BinaryOperator>(E)) { 7701 BinaryOperator *Op = cast<BinaryOperator>(E); 7702 if (Op->getOpcode() != BinaryOperator::Assign) 7703 return; 7704 7705 // Greylist some idioms by putting them into a warning subcategory. 7706 if (ObjCMessageExpr *ME 7707 = dyn_cast<ObjCMessageExpr>(Op->getRHS()->IgnoreParenCasts())) { 7708 Selector Sel = ME->getSelector(); 7709 7710 // self = [<foo> init...] 7711 if (isSelfExpr(Op->getLHS()) 7712 && Sel.getIdentifierInfoForSlot(0)->getName().startswith("init")) 7713 diagnostic = diag::warn_condition_is_idiomatic_assignment; 7714 7715 // <foo> = [<bar> nextObject] 7716 else if (Sel.isUnarySelector() && 7717 Sel.getIdentifierInfoForSlot(0)->getName() == "nextObject") 7718 diagnostic = diag::warn_condition_is_idiomatic_assignment; 7719 } 7720 7721 Loc = Op->getOperatorLoc(); 7722 } else if (isa<CXXOperatorCallExpr>(E)) { 7723 CXXOperatorCallExpr *Op = cast<CXXOperatorCallExpr>(E); 7724 if (Op->getOperator() != OO_Equal) 7725 return; 7726 7727 Loc = Op->getOperatorLoc(); 7728 } else { 7729 // Not an assignment. 7730 return; 7731 } 7732 7733 SourceLocation Open = E->getSourceRange().getBegin(); 7734 SourceLocation Close = PP.getLocForEndOfToken(E->getSourceRange().getEnd()); 7735 7736 Diag(Loc, diagnostic) << E->getSourceRange(); 7737 Diag(Loc, diag::note_condition_assign_to_comparison) 7738 << FixItHint::CreateReplacement(Loc, "=="); 7739 Diag(Loc, diag::note_condition_assign_silence) 7740 << FixItHint::CreateInsertion(Open, "(") 7741 << FixItHint::CreateInsertion(Close, ")"); 7742} 7743 7744bool Sema::CheckBooleanCondition(Expr *&E, SourceLocation Loc) { 7745 DiagnoseAssignmentAsCondition(E); 7746 7747 if (!E->isTypeDependent()) { 7748 DefaultFunctionArrayLvalueConversion(E); 7749 7750 QualType T = E->getType(); 7751 7752 if (getLangOptions().CPlusPlus) { 7753 if (CheckCXXBooleanCondition(E)) // C++ 6.4p4 7754 return true; 7755 } else if (!T->isScalarType()) { // C99 6.8.4.1p1 7756 Diag(Loc, diag::err_typecheck_statement_requires_scalar) 7757 << T << E->getSourceRange(); 7758 return true; 7759 } 7760 } 7761 7762 return false; 7763} 7764 7765Sema::OwningExprResult Sema::ActOnBooleanCondition(Scope *S, SourceLocation Loc, 7766 ExprArg SubExpr) { 7767 Expr *Sub = SubExpr.takeAs<Expr>(); 7768 if (!Sub) 7769 return ExprError(); 7770 7771 if (CheckBooleanCondition(Sub, Loc)) { 7772 Sub->Destroy(Context); 7773 return ExprError(); 7774 } 7775 7776 return Owned(Sub); 7777} 7778