SemaExpr.cpp revision 4fdcdda2862ac8c818184ca593ef43ff11469eac
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 "clang/AST/ASTContext.h" 16#include "clang/AST/DeclObjC.h" 17#include "clang/AST/ExprCXX.h" 18#include "clang/AST/ExprObjC.h" 19#include "clang/AST/DeclTemplate.h" 20#include "clang/Lex/Preprocessor.h" 21#include "clang/Lex/LiteralSupport.h" 22#include "clang/Basic/SourceManager.h" 23#include "clang/Basic/TargetInfo.h" 24#include "clang/Parse/DeclSpec.h" 25#include "clang/Parse/Designator.h" 26#include "clang/Parse/Scope.h" 27using namespace clang; 28 29 30/// \brief Determine whether the use of this declaration is valid, and 31/// emit any corresponding diagnostics. 32/// 33/// This routine diagnoses various problems with referencing 34/// declarations that can occur when using a declaration. For example, 35/// it might warn if a deprecated or unavailable declaration is being 36/// used, or produce an error (and return true) if a C++0x deleted 37/// function is being used. 38/// 39/// \returns true if there was an error (this declaration cannot be 40/// referenced), false otherwise. 41bool Sema::DiagnoseUseOfDecl(NamedDecl *D, SourceLocation Loc) { 42 // See if the decl is deprecated. 43 if (D->getAttr<DeprecatedAttr>()) { 44 // Implementing deprecated stuff requires referencing deprecated 45 // stuff. Don't warn if we are implementing a deprecated 46 // construct. 47 bool isSilenced = false; 48 49 if (NamedDecl *ND = getCurFunctionOrMethodDecl()) { 50 // If this reference happens *in* a deprecated function or method, don't 51 // warn. 52 isSilenced = ND->getAttr<DeprecatedAttr>(); 53 54 // If this is an Objective-C method implementation, check to see if the 55 // method was deprecated on the declaration, not the definition. 56 if (ObjCMethodDecl *MD = dyn_cast<ObjCMethodDecl>(ND)) { 57 // The semantic decl context of a ObjCMethodDecl is the 58 // ObjCImplementationDecl. 59 if (ObjCImplementationDecl *Impl 60 = dyn_cast<ObjCImplementationDecl>(MD->getParent())) { 61 62 MD = Impl->getClassInterface()->getMethod(MD->getSelector(), 63 MD->isInstanceMethod()); 64 isSilenced |= MD && MD->getAttr<DeprecatedAttr>(); 65 } 66 } 67 } 68 69 if (!isSilenced) 70 Diag(Loc, diag::warn_deprecated) << D->getDeclName(); 71 } 72 73 // See if this is a deleted function. 74 if (FunctionDecl *FD = dyn_cast<FunctionDecl>(D)) { 75 if (FD->isDeleted()) { 76 Diag(Loc, diag::err_deleted_function_use); 77 Diag(D->getLocation(), diag::note_unavailable_here) << true; 78 return true; 79 } 80 } 81 82 // See if the decl is unavailable 83 if (D->getAttr<UnavailableAttr>()) { 84 Diag(Loc, diag::warn_unavailable) << D->getDeclName(); 85 Diag(D->getLocation(), diag::note_unavailable_here) << 0; 86 } 87 88 return false; 89} 90 91/// DiagnoseSentinelCalls - This routine checks on method dispatch calls 92/// (and other functions in future), which have been declared with sentinel 93/// attribute. It warns if call does not have the sentinel argument. 94/// 95void Sema::DiagnoseSentinelCalls(NamedDecl *D, SourceLocation Loc, 96 Expr **Args, unsigned NumArgs) 97{ 98 const SentinelAttr *attr = D->getAttr<SentinelAttr>(); 99 if (!attr) 100 return; 101 int sentinelPos = attr->getSentinel(); 102 int nullPos = attr->getNullPos(); 103 104 // FIXME. ObjCMethodDecl and FunctionDecl need be derived from the same common 105 // base class. Then we won't be needing two versions of the same code. 106 unsigned int i = 0; 107 bool warnNotEnoughArgs = false; 108 int isMethod = 0; 109 if (ObjCMethodDecl *MD = dyn_cast<ObjCMethodDecl>(D)) { 110 // skip over named parameters. 111 ObjCMethodDecl::param_iterator P, E = MD->param_end(); 112 for (P = MD->param_begin(); (P != E && i < NumArgs); ++P) { 113 if (nullPos) 114 --nullPos; 115 else 116 ++i; 117 } 118 warnNotEnoughArgs = (P != E || i >= NumArgs); 119 isMethod = 1; 120 } else if (FunctionDecl *FD = dyn_cast<FunctionDecl>(D)) { 121 // skip over named parameters. 122 ObjCMethodDecl::param_iterator P, E = FD->param_end(); 123 for (P = FD->param_begin(); (P != E && i < NumArgs); ++P) { 124 if (nullPos) 125 --nullPos; 126 else 127 ++i; 128 } 129 warnNotEnoughArgs = (P != E || i >= NumArgs); 130 } else if (VarDecl *V = dyn_cast<VarDecl>(D)) { 131 // block or function pointer call. 132 QualType Ty = V->getType(); 133 if (Ty->isBlockPointerType() || Ty->isFunctionPointerType()) { 134 const FunctionType *FT = Ty->isFunctionPointerType() 135 ? Ty->getAs<PointerType>()->getPointeeType()->getAsFunctionType() 136 : Ty->getAs<BlockPointerType>()->getPointeeType()->getAsFunctionType(); 137 if (const FunctionProtoType *Proto = dyn_cast<FunctionProtoType>(FT)) { 138 unsigned NumArgsInProto = Proto->getNumArgs(); 139 unsigned k; 140 for (k = 0; (k != NumArgsInProto && i < NumArgs); k++) { 141 if (nullPos) 142 --nullPos; 143 else 144 ++i; 145 } 146 warnNotEnoughArgs = (k != NumArgsInProto || i >= NumArgs); 147 } 148 if (Ty->isBlockPointerType()) 149 isMethod = 2; 150 } else 151 return; 152 } else 153 return; 154 155 if (warnNotEnoughArgs) { 156 Diag(Loc, diag::warn_not_enough_argument) << D->getDeclName(); 157 Diag(D->getLocation(), diag::note_sentinel_here) << isMethod; 158 return; 159 } 160 int sentinel = i; 161 while (sentinelPos > 0 && i < NumArgs-1) { 162 --sentinelPos; 163 ++i; 164 } 165 if (sentinelPos > 0) { 166 Diag(Loc, diag::warn_not_enough_argument) << D->getDeclName(); 167 Diag(D->getLocation(), diag::note_sentinel_here) << isMethod; 168 return; 169 } 170 while (i < NumArgs-1) { 171 ++i; 172 ++sentinel; 173 } 174 Expr *sentinelExpr = Args[sentinel]; 175 if (sentinelExpr && (!sentinelExpr->getType()->isPointerType() || 176 !sentinelExpr->isNullPointerConstant(Context))) { 177 Diag(Loc, diag::warn_missing_sentinel) << isMethod; 178 Diag(D->getLocation(), diag::note_sentinel_here) << isMethod; 179 } 180 return; 181} 182 183SourceRange Sema::getExprRange(ExprTy *E) const { 184 Expr *Ex = (Expr *)E; 185 return Ex? Ex->getSourceRange() : SourceRange(); 186} 187 188//===----------------------------------------------------------------------===// 189// Standard Promotions and Conversions 190//===----------------------------------------------------------------------===// 191 192/// DefaultFunctionArrayConversion (C99 6.3.2.1p3, C99 6.3.2.1p4). 193void Sema::DefaultFunctionArrayConversion(Expr *&E) { 194 QualType Ty = E->getType(); 195 assert(!Ty.isNull() && "DefaultFunctionArrayConversion - missing type"); 196 197 if (Ty->isFunctionType()) 198 ImpCastExprToType(E, Context.getPointerType(Ty)); 199 else if (Ty->isArrayType()) { 200 // In C90 mode, arrays only promote to pointers if the array expression is 201 // an lvalue. The relevant legalese is C90 6.2.2.1p3: "an lvalue that has 202 // type 'array of type' is converted to an expression that has type 'pointer 203 // to type'...". In C99 this was changed to: C99 6.3.2.1p3: "an expression 204 // that has type 'array of type' ...". The relevant change is "an lvalue" 205 // (C90) to "an expression" (C99). 206 // 207 // C++ 4.2p1: 208 // An lvalue or rvalue of type "array of N T" or "array of unknown bound of 209 // T" can be converted to an rvalue of type "pointer to T". 210 // 211 if (getLangOptions().C99 || getLangOptions().CPlusPlus || 212 E->isLvalue(Context) == Expr::LV_Valid) 213 ImpCastExprToType(E, Context.getArrayDecayedType(Ty), 214 CastExpr::CK_ArrayToPointerDecay); 215 } 216} 217 218/// UsualUnaryConversions - Performs various conversions that are common to most 219/// operators (C99 6.3). The conversions of array and function types are 220/// sometimes surpressed. For example, the array->pointer conversion doesn't 221/// apply if the array is an argument to the sizeof or address (&) operators. 222/// In these instances, this routine should *not* be called. 223Expr *Sema::UsualUnaryConversions(Expr *&Expr) { 224 QualType Ty = Expr->getType(); 225 assert(!Ty.isNull() && "UsualUnaryConversions - missing type"); 226 227 // C99 6.3.1.1p2: 228 // 229 // The following may be used in an expression wherever an int or 230 // unsigned int may be used: 231 // - an object or expression with an integer type whose integer 232 // conversion rank is less than or equal to the rank of int 233 // and unsigned int. 234 // - A bit-field of type _Bool, int, signed int, or unsigned int. 235 // 236 // If an int can represent all values of the original type, the 237 // value is converted to an int; otherwise, it is converted to an 238 // unsigned int. These are called the integer promotions. All 239 // other types are unchanged by the integer promotions. 240 QualType PTy = Context.isPromotableBitField(Expr); 241 if (!PTy.isNull()) { 242 ImpCastExprToType(Expr, PTy); 243 return Expr; 244 } 245 if (Ty->isPromotableIntegerType()) { 246 QualType PT = Context.getPromotedIntegerType(Ty); 247 ImpCastExprToType(Expr, PT); 248 return Expr; 249 } 250 251 DefaultFunctionArrayConversion(Expr); 252 return Expr; 253} 254 255/// DefaultArgumentPromotion (C99 6.5.2.2p6). Used for function calls that 256/// do not have a prototype. Arguments that have type float are promoted to 257/// double. All other argument types are converted by UsualUnaryConversions(). 258void Sema::DefaultArgumentPromotion(Expr *&Expr) { 259 QualType Ty = Expr->getType(); 260 assert(!Ty.isNull() && "DefaultArgumentPromotion - missing type"); 261 262 // If this is a 'float' (CVR qualified or typedef) promote to double. 263 if (const BuiltinType *BT = Ty->getAsBuiltinType()) 264 if (BT->getKind() == BuiltinType::Float) 265 return ImpCastExprToType(Expr, Context.DoubleTy); 266 267 UsualUnaryConversions(Expr); 268} 269 270/// DefaultVariadicArgumentPromotion - Like DefaultArgumentPromotion, but 271/// will warn if the resulting type is not a POD type, and rejects ObjC 272/// interfaces passed by value. This returns true if the argument type is 273/// completely illegal. 274bool Sema::DefaultVariadicArgumentPromotion(Expr *&Expr, VariadicCallType CT) { 275 DefaultArgumentPromotion(Expr); 276 277 if (Expr->getType()->isObjCInterfaceType()) { 278 Diag(Expr->getLocStart(), 279 diag::err_cannot_pass_objc_interface_to_vararg) 280 << Expr->getType() << CT; 281 return true; 282 } 283 284 if (!Expr->getType()->isPODType()) 285 Diag(Expr->getLocStart(), diag::warn_cannot_pass_non_pod_arg_to_vararg) 286 << Expr->getType() << CT; 287 288 return false; 289} 290 291 292/// UsualArithmeticConversions - Performs various conversions that are common to 293/// binary operators (C99 6.3.1.8). If both operands aren't arithmetic, this 294/// routine returns the first non-arithmetic type found. The client is 295/// responsible for emitting appropriate error diagnostics. 296/// FIXME: verify the conversion rules for "complex int" are consistent with 297/// GCC. 298QualType Sema::UsualArithmeticConversions(Expr *&lhsExpr, Expr *&rhsExpr, 299 bool isCompAssign) { 300 if (!isCompAssign) 301 UsualUnaryConversions(lhsExpr); 302 303 UsualUnaryConversions(rhsExpr); 304 305 // For conversion purposes, we ignore any qualifiers. 306 // For example, "const float" and "float" are equivalent. 307 QualType lhs = 308 Context.getCanonicalType(lhsExpr->getType()).getUnqualifiedType(); 309 QualType rhs = 310 Context.getCanonicalType(rhsExpr->getType()).getUnqualifiedType(); 311 312 // If both types are identical, no conversion is needed. 313 if (lhs == rhs) 314 return lhs; 315 316 // If either side is a non-arithmetic type (e.g. a pointer), we are done. 317 // The caller can deal with this (e.g. pointer + int). 318 if (!lhs->isArithmeticType() || !rhs->isArithmeticType()) 319 return lhs; 320 321 // Perform bitfield promotions. 322 QualType LHSBitfieldPromoteTy = Context.isPromotableBitField(lhsExpr); 323 if (!LHSBitfieldPromoteTy.isNull()) 324 lhs = LHSBitfieldPromoteTy; 325 QualType RHSBitfieldPromoteTy = Context.isPromotableBitField(rhsExpr); 326 if (!RHSBitfieldPromoteTy.isNull()) 327 rhs = RHSBitfieldPromoteTy; 328 329 QualType destType = Context.UsualArithmeticConversionsType(lhs, rhs); 330 if (!isCompAssign) 331 ImpCastExprToType(lhsExpr, destType); 332 ImpCastExprToType(rhsExpr, destType); 333 return destType; 334} 335 336//===----------------------------------------------------------------------===// 337// Semantic Analysis for various Expression Types 338//===----------------------------------------------------------------------===// 339 340 341/// ActOnStringLiteral - The specified tokens were lexed as pasted string 342/// fragments (e.g. "foo" "bar" L"baz"). The result string has to handle string 343/// concatenation ([C99 5.1.1.2, translation phase #6]), so it may come from 344/// multiple tokens. However, the common case is that StringToks points to one 345/// string. 346/// 347Action::OwningExprResult 348Sema::ActOnStringLiteral(const Token *StringToks, unsigned NumStringToks) { 349 assert(NumStringToks && "Must have at least one string!"); 350 351 StringLiteralParser Literal(StringToks, NumStringToks, PP); 352 if (Literal.hadError) 353 return ExprError(); 354 355 llvm::SmallVector<SourceLocation, 4> StringTokLocs; 356 for (unsigned i = 0; i != NumStringToks; ++i) 357 StringTokLocs.push_back(StringToks[i].getLocation()); 358 359 QualType StrTy = Context.CharTy; 360 if (Literal.AnyWide) StrTy = Context.getWCharType(); 361 if (Literal.Pascal) StrTy = Context.UnsignedCharTy; 362 363 // A C++ string literal has a const-qualified element type (C++ 2.13.4p1). 364 if (getLangOptions().CPlusPlus) 365 StrTy.addConst(); 366 367 // Get an array type for the string, according to C99 6.4.5. This includes 368 // the nul terminator character as well as the string length for pascal 369 // strings. 370 StrTy = Context.getConstantArrayType(StrTy, 371 llvm::APInt(32, Literal.GetNumStringChars()+1), 372 ArrayType::Normal, 0); 373 374 // Pass &StringTokLocs[0], StringTokLocs.size() to factory! 375 return Owned(StringLiteral::Create(Context, Literal.GetString(), 376 Literal.GetStringLength(), 377 Literal.AnyWide, StrTy, 378 &StringTokLocs[0], 379 StringTokLocs.size())); 380} 381 382/// ShouldSnapshotBlockValueReference - Return true if a reference inside of 383/// CurBlock to VD should cause it to be snapshotted (as we do for auto 384/// variables defined outside the block) or false if this is not needed (e.g. 385/// for values inside the block or for globals). 386/// 387/// This also keeps the 'hasBlockDeclRefExprs' in the BlockSemaInfo records 388/// up-to-date. 389/// 390static bool ShouldSnapshotBlockValueReference(BlockSemaInfo *CurBlock, 391 ValueDecl *VD) { 392 // If the value is defined inside the block, we couldn't snapshot it even if 393 // we wanted to. 394 if (CurBlock->TheDecl == VD->getDeclContext()) 395 return false; 396 397 // If this is an enum constant or function, it is constant, don't snapshot. 398 if (isa<EnumConstantDecl>(VD) || isa<FunctionDecl>(VD)) 399 return false; 400 401 // If this is a reference to an extern, static, or global variable, no need to 402 // snapshot it. 403 // FIXME: What about 'const' variables in C++? 404 if (const VarDecl *Var = dyn_cast<VarDecl>(VD)) 405 if (!Var->hasLocalStorage()) 406 return false; 407 408 // Blocks that have these can't be constant. 409 CurBlock->hasBlockDeclRefExprs = true; 410 411 // If we have nested blocks, the decl may be declared in an outer block (in 412 // which case that outer block doesn't get "hasBlockDeclRefExprs") or it may 413 // be defined outside all of the current blocks (in which case the blocks do 414 // all get the bit). Walk the nesting chain. 415 for (BlockSemaInfo *NextBlock = CurBlock->PrevBlockInfo; NextBlock; 416 NextBlock = NextBlock->PrevBlockInfo) { 417 // If we found the defining block for the variable, don't mark the block as 418 // having a reference outside it. 419 if (NextBlock->TheDecl == VD->getDeclContext()) 420 break; 421 422 // Otherwise, the DeclRef from the inner block causes the outer one to need 423 // a snapshot as well. 424 NextBlock->hasBlockDeclRefExprs = true; 425 } 426 427 return true; 428} 429 430 431 432/// ActOnIdentifierExpr - The parser read an identifier in expression context, 433/// validate it per-C99 6.5.1. HasTrailingLParen indicates whether this 434/// identifier is used in a function call context. 435/// SS is only used for a C++ qualified-id (foo::bar) to indicate the 436/// class or namespace that the identifier must be a member of. 437Sema::OwningExprResult Sema::ActOnIdentifierExpr(Scope *S, SourceLocation Loc, 438 IdentifierInfo &II, 439 bool HasTrailingLParen, 440 const CXXScopeSpec *SS, 441 bool isAddressOfOperand) { 442 return ActOnDeclarationNameExpr(S, Loc, &II, HasTrailingLParen, SS, 443 isAddressOfOperand); 444} 445 446/// BuildDeclRefExpr - Build either a DeclRefExpr or a 447/// QualifiedDeclRefExpr based on whether or not SS is a 448/// nested-name-specifier. 449Sema::OwningExprResult 450Sema::BuildDeclRefExpr(NamedDecl *D, QualType Ty, SourceLocation Loc, 451 bool TypeDependent, bool ValueDependent, 452 const CXXScopeSpec *SS) { 453 if (Context.getCanonicalType(Ty) == Context.UndeducedAutoTy) { 454 Diag(Loc, 455 diag::err_auto_variable_cannot_appear_in_own_initializer) 456 << D->getDeclName(); 457 return ExprError(); 458 } 459 460 if (const VarDecl *VD = dyn_cast<VarDecl>(D)) { 461 if (const CXXMethodDecl *MD = dyn_cast<CXXMethodDecl>(CurContext)) { 462 if (const FunctionDecl *FD = MD->getParent()->isLocalClass()) { 463 if (VD->hasLocalStorage() && VD->getDeclContext() != CurContext) { 464 Diag(Loc, diag::err_reference_to_local_var_in_enclosing_function) 465 << D->getIdentifier() << FD->getDeclName(); 466 Diag(D->getLocation(), diag::note_local_variable_declared_here) 467 << D->getIdentifier(); 468 return ExprError(); 469 } 470 } 471 } 472 } 473 474 MarkDeclarationReferenced(Loc, D); 475 476 Expr *E; 477 if (SS && !SS->isEmpty()) { 478 E = new (Context) QualifiedDeclRefExpr(D, Ty, Loc, TypeDependent, 479 ValueDependent, SS->getRange(), 480 static_cast<NestedNameSpecifier *>(SS->getScopeRep())); 481 } else 482 E = new (Context) DeclRefExpr(D, Ty, Loc, TypeDependent, ValueDependent); 483 484 return Owned(E); 485} 486 487/// getObjectForAnonymousRecordDecl - Retrieve the (unnamed) field or 488/// variable corresponding to the anonymous union or struct whose type 489/// is Record. 490static Decl *getObjectForAnonymousRecordDecl(ASTContext &Context, 491 RecordDecl *Record) { 492 assert(Record->isAnonymousStructOrUnion() && 493 "Record must be an anonymous struct or union!"); 494 495 // FIXME: Once Decls are directly linked together, this will be an O(1) 496 // operation rather than a slow walk through DeclContext's vector (which 497 // itself will be eliminated). DeclGroups might make this even better. 498 DeclContext *Ctx = Record->getDeclContext(); 499 for (DeclContext::decl_iterator D = Ctx->decls_begin(), 500 DEnd = Ctx->decls_end(); 501 D != DEnd; ++D) { 502 if (*D == Record) { 503 // The object for the anonymous struct/union directly 504 // follows its type in the list of declarations. 505 ++D; 506 assert(D != DEnd && "Missing object for anonymous record"); 507 assert(!cast<NamedDecl>(*D)->getDeclName() && "Decl should be unnamed"); 508 return *D; 509 } 510 } 511 512 assert(false && "Missing object for anonymous record"); 513 return 0; 514} 515 516/// \brief Given a field that represents a member of an anonymous 517/// struct/union, build the path from that field's context to the 518/// actual member. 519/// 520/// Construct the sequence of field member references we'll have to 521/// perform to get to the field in the anonymous union/struct. The 522/// list of members is built from the field outward, so traverse it 523/// backwards to go from an object in the current context to the field 524/// we found. 525/// 526/// \returns The variable from which the field access should begin, 527/// for an anonymous struct/union that is not a member of another 528/// class. Otherwise, returns NULL. 529VarDecl *Sema::BuildAnonymousStructUnionMemberPath(FieldDecl *Field, 530 llvm::SmallVectorImpl<FieldDecl *> &Path) { 531 assert(Field->getDeclContext()->isRecord() && 532 cast<RecordDecl>(Field->getDeclContext())->isAnonymousStructOrUnion() 533 && "Field must be stored inside an anonymous struct or union"); 534 535 Path.push_back(Field); 536 VarDecl *BaseObject = 0; 537 DeclContext *Ctx = Field->getDeclContext(); 538 do { 539 RecordDecl *Record = cast<RecordDecl>(Ctx); 540 Decl *AnonObject = getObjectForAnonymousRecordDecl(Context, Record); 541 if (FieldDecl *AnonField = dyn_cast<FieldDecl>(AnonObject)) 542 Path.push_back(AnonField); 543 else { 544 BaseObject = cast<VarDecl>(AnonObject); 545 break; 546 } 547 Ctx = Ctx->getParent(); 548 } while (Ctx->isRecord() && 549 cast<RecordDecl>(Ctx)->isAnonymousStructOrUnion()); 550 551 return BaseObject; 552} 553 554Sema::OwningExprResult 555Sema::BuildAnonymousStructUnionMemberReference(SourceLocation Loc, 556 FieldDecl *Field, 557 Expr *BaseObjectExpr, 558 SourceLocation OpLoc) { 559 llvm::SmallVector<FieldDecl *, 4> AnonFields; 560 VarDecl *BaseObject = BuildAnonymousStructUnionMemberPath(Field, 561 AnonFields); 562 563 // Build the expression that refers to the base object, from 564 // which we will build a sequence of member references to each 565 // of the anonymous union objects and, eventually, the field we 566 // found via name lookup. 567 bool BaseObjectIsPointer = false; 568 unsigned ExtraQuals = 0; 569 if (BaseObject) { 570 // BaseObject is an anonymous struct/union variable (and is, 571 // therefore, not part of another non-anonymous record). 572 if (BaseObjectExpr) BaseObjectExpr->Destroy(Context); 573 MarkDeclarationReferenced(Loc, BaseObject); 574 BaseObjectExpr = new (Context) DeclRefExpr(BaseObject,BaseObject->getType(), 575 SourceLocation()); 576 ExtraQuals 577 = Context.getCanonicalType(BaseObject->getType()).getCVRQualifiers(); 578 } else if (BaseObjectExpr) { 579 // The caller provided the base object expression. Determine 580 // whether its a pointer and whether it adds any qualifiers to the 581 // anonymous struct/union fields we're looking into. 582 QualType ObjectType = BaseObjectExpr->getType(); 583 if (const PointerType *ObjectPtr = ObjectType->getAs<PointerType>()) { 584 BaseObjectIsPointer = true; 585 ObjectType = ObjectPtr->getPointeeType(); 586 } 587 ExtraQuals = Context.getCanonicalType(ObjectType).getCVRQualifiers(); 588 } else { 589 // We've found a member of an anonymous struct/union that is 590 // inside a non-anonymous struct/union, so in a well-formed 591 // program our base object expression is "this". 592 if (CXXMethodDecl *MD = dyn_cast<CXXMethodDecl>(CurContext)) { 593 if (!MD->isStatic()) { 594 QualType AnonFieldType 595 = Context.getTagDeclType( 596 cast<RecordDecl>(AnonFields.back()->getDeclContext())); 597 QualType ThisType = Context.getTagDeclType(MD->getParent()); 598 if ((Context.getCanonicalType(AnonFieldType) 599 == Context.getCanonicalType(ThisType)) || 600 IsDerivedFrom(ThisType, AnonFieldType)) { 601 // Our base object expression is "this". 602 BaseObjectExpr = new (Context) CXXThisExpr(SourceLocation(), 603 MD->getThisType(Context)); 604 BaseObjectIsPointer = true; 605 } 606 } else { 607 return ExprError(Diag(Loc,diag::err_invalid_member_use_in_static_method) 608 << Field->getDeclName()); 609 } 610 ExtraQuals = MD->getTypeQualifiers(); 611 } 612 613 if (!BaseObjectExpr) 614 return ExprError(Diag(Loc, diag::err_invalid_non_static_member_use) 615 << Field->getDeclName()); 616 } 617 618 // Build the implicit member references to the field of the 619 // anonymous struct/union. 620 Expr *Result = BaseObjectExpr; 621 unsigned BaseAddrSpace = BaseObjectExpr->getType().getAddressSpace(); 622 for (llvm::SmallVector<FieldDecl *, 4>::reverse_iterator 623 FI = AnonFields.rbegin(), FIEnd = AnonFields.rend(); 624 FI != FIEnd; ++FI) { 625 QualType MemberType = (*FI)->getType(); 626 if (!(*FI)->isMutable()) { 627 unsigned combinedQualifiers 628 = MemberType.getCVRQualifiers() | ExtraQuals; 629 MemberType = MemberType.getQualifiedType(combinedQualifiers); 630 } 631 if (BaseAddrSpace != MemberType.getAddressSpace()) 632 MemberType = Context.getAddrSpaceQualType(MemberType, BaseAddrSpace); 633 MarkDeclarationReferenced(Loc, *FI); 634 Result = new (Context) MemberExpr(Result, BaseObjectIsPointer, *FI, 635 OpLoc, MemberType); 636 BaseObjectIsPointer = false; 637 ExtraQuals = Context.getCanonicalType(MemberType).getCVRQualifiers(); 638 } 639 640 return Owned(Result); 641} 642 643/// ActOnDeclarationNameExpr - The parser has read some kind of name 644/// (e.g., a C++ id-expression (C++ [expr.prim]p1)). This routine 645/// performs lookup on that name and returns an expression that refers 646/// to that name. This routine isn't directly called from the parser, 647/// because the parser doesn't know about DeclarationName. Rather, 648/// this routine is called by ActOnIdentifierExpr, 649/// ActOnOperatorFunctionIdExpr, and ActOnConversionFunctionExpr, 650/// which form the DeclarationName from the corresponding syntactic 651/// forms. 652/// 653/// HasTrailingLParen indicates whether this identifier is used in a 654/// function call context. LookupCtx is only used for a C++ 655/// qualified-id (foo::bar) to indicate the class or namespace that 656/// the identifier must be a member of. 657/// 658/// isAddressOfOperand means that this expression is the direct operand 659/// of an address-of operator. This matters because this is the only 660/// situation where a qualified name referencing a non-static member may 661/// appear outside a member function of this class. 662Sema::OwningExprResult 663Sema::ActOnDeclarationNameExpr(Scope *S, SourceLocation Loc, 664 DeclarationName Name, bool HasTrailingLParen, 665 const CXXScopeSpec *SS, 666 bool isAddressOfOperand) { 667 // Could be enum-constant, value decl, instance variable, etc. 668 if (SS && SS->isInvalid()) 669 return ExprError(); 670 671 // C++ [temp.dep.expr]p3: 672 // An id-expression is type-dependent if it contains: 673 // -- a nested-name-specifier that contains a class-name that 674 // names a dependent type. 675 // FIXME: Member of the current instantiation. 676 if (SS && isDependentScopeSpecifier(*SS)) { 677 return Owned(new (Context) UnresolvedDeclRefExpr(Name, Context.DependentTy, 678 Loc, SS->getRange(), 679 static_cast<NestedNameSpecifier *>(SS->getScopeRep()), 680 isAddressOfOperand)); 681 } 682 683 LookupResult Lookup = LookupParsedName(S, SS, Name, LookupOrdinaryName, 684 false, true, Loc); 685 686 if (Lookup.isAmbiguous()) { 687 DiagnoseAmbiguousLookup(Lookup, Name, Loc, 688 SS && SS->isSet() ? SS->getRange() 689 : SourceRange()); 690 return ExprError(); 691 } 692 693 NamedDecl *D = Lookup.getAsDecl(); 694 695 // If this reference is in an Objective-C method, then ivar lookup happens as 696 // well. 697 IdentifierInfo *II = Name.getAsIdentifierInfo(); 698 if (II && getCurMethodDecl()) { 699 // There are two cases to handle here. 1) scoped lookup could have failed, 700 // in which case we should look for an ivar. 2) scoped lookup could have 701 // found a decl, but that decl is outside the current instance method (i.e. 702 // a global variable). In these two cases, we do a lookup for an ivar with 703 // this name, if the lookup sucedes, we replace it our current decl. 704 if (D == 0 || D->isDefinedOutsideFunctionOrMethod()) { 705 ObjCInterfaceDecl *IFace = getCurMethodDecl()->getClassInterface(); 706 ObjCInterfaceDecl *ClassDeclared; 707 if (ObjCIvarDecl *IV = IFace->lookupInstanceVariable(II, ClassDeclared)) { 708 // Check if referencing a field with __attribute__((deprecated)). 709 if (DiagnoseUseOfDecl(IV, Loc)) 710 return ExprError(); 711 712 // If we're referencing an invalid decl, just return this as a silent 713 // error node. The error diagnostic was already emitted on the decl. 714 if (IV->isInvalidDecl()) 715 return ExprError(); 716 717 bool IsClsMethod = getCurMethodDecl()->isClassMethod(); 718 // If a class method attemps to use a free standing ivar, this is 719 // an error. 720 if (IsClsMethod && D && !D->isDefinedOutsideFunctionOrMethod()) 721 return ExprError(Diag(Loc, diag::error_ivar_use_in_class_method) 722 << IV->getDeclName()); 723 // If a class method uses a global variable, even if an ivar with 724 // same name exists, use the global. 725 if (!IsClsMethod) { 726 if (IV->getAccessControl() == ObjCIvarDecl::Private && 727 ClassDeclared != IFace) 728 Diag(Loc, diag::error_private_ivar_access) << IV->getDeclName(); 729 // FIXME: This should use a new expr for a direct reference, don't 730 // turn this into Self->ivar, just return a BareIVarExpr or something. 731 IdentifierInfo &II = Context.Idents.get("self"); 732 OwningExprResult SelfExpr = ActOnIdentifierExpr(S, SourceLocation(), 733 II, false); 734 MarkDeclarationReferenced(Loc, IV); 735 return Owned(new (Context) 736 ObjCIvarRefExpr(IV, IV->getType(), Loc, 737 SelfExpr.takeAs<Expr>(), true, true)); 738 } 739 } 740 } else if (getCurMethodDecl()->isInstanceMethod()) { 741 // We should warn if a local variable hides an ivar. 742 ObjCInterfaceDecl *IFace = getCurMethodDecl()->getClassInterface(); 743 ObjCInterfaceDecl *ClassDeclared; 744 if (ObjCIvarDecl *IV = IFace->lookupInstanceVariable(II, ClassDeclared)) { 745 if (IV->getAccessControl() != ObjCIvarDecl::Private || 746 IFace == ClassDeclared) 747 Diag(Loc, diag::warn_ivar_use_hidden) << IV->getDeclName(); 748 } 749 } 750 // Needed to implement property "super.method" notation. 751 if (D == 0 && II->isStr("super")) { 752 QualType T; 753 754 if (getCurMethodDecl()->isInstanceMethod()) 755 T = Context.getObjCObjectPointerType(Context.getObjCInterfaceType( 756 getCurMethodDecl()->getClassInterface())); 757 else 758 T = Context.getObjCClassType(); 759 return Owned(new (Context) ObjCSuperExpr(Loc, T)); 760 } 761 } 762 763 // Determine whether this name might be a candidate for 764 // argument-dependent lookup. 765 bool ADL = getLangOptions().CPlusPlus && (!SS || !SS->isSet()) && 766 HasTrailingLParen; 767 768 if (ADL && D == 0) { 769 // We've seen something of the form 770 // 771 // identifier( 772 // 773 // and we did not find any entity by the name 774 // "identifier". However, this identifier is still subject to 775 // argument-dependent lookup, so keep track of the name. 776 return Owned(new (Context) UnresolvedFunctionNameExpr(Name, 777 Context.OverloadTy, 778 Loc)); 779 } 780 781 if (D == 0) { 782 // Otherwise, this could be an implicitly declared function reference (legal 783 // in C90, extension in C99). 784 if (HasTrailingLParen && II && 785 !getLangOptions().CPlusPlus) // Not in C++. 786 D = ImplicitlyDefineFunction(Loc, *II, S); 787 else { 788 // If this name wasn't predeclared and if this is not a function call, 789 // diagnose the problem. 790 if (SS && !SS->isEmpty()) 791 return ExprError(Diag(Loc, diag::err_typecheck_no_member) 792 << Name << SS->getRange()); 793 else if (Name.getNameKind() == DeclarationName::CXXOperatorName || 794 Name.getNameKind() == DeclarationName::CXXConversionFunctionName) 795 return ExprError(Diag(Loc, diag::err_undeclared_use) 796 << Name.getAsString()); 797 else 798 return ExprError(Diag(Loc, diag::err_undeclared_var_use) << Name); 799 } 800 } 801 802 if (VarDecl *Var = dyn_cast<VarDecl>(D)) { 803 // Warn about constructs like: 804 // if (void *X = foo()) { ... } else { X }. 805 // In the else block, the pointer is always false. 806 807 // FIXME: In a template instantiation, we don't have scope 808 // information to check this property. 809 if (Var->isDeclaredInCondition() && Var->getType()->isScalarType()) { 810 Scope *CheckS = S; 811 while (CheckS) { 812 if (CheckS->isWithinElse() && 813 CheckS->getControlParent()->isDeclScope(DeclPtrTy::make(Var))) { 814 if (Var->getType()->isBooleanType()) 815 ExprError(Diag(Loc, diag::warn_value_always_false) 816 << Var->getDeclName()); 817 else 818 ExprError(Diag(Loc, diag::warn_value_always_zero) 819 << Var->getDeclName()); 820 break; 821 } 822 823 // Move up one more control parent to check again. 824 CheckS = CheckS->getControlParent(); 825 if (CheckS) 826 CheckS = CheckS->getParent(); 827 } 828 } 829 } else if (FunctionDecl *Func = dyn_cast<FunctionDecl>(D)) { 830 if (!getLangOptions().CPlusPlus && !Func->hasPrototype()) { 831 // C99 DR 316 says that, if a function type comes from a 832 // function definition (without a prototype), that type is only 833 // used for checking compatibility. Therefore, when referencing 834 // the function, we pretend that we don't have the full function 835 // type. 836 if (DiagnoseUseOfDecl(Func, Loc)) 837 return ExprError(); 838 839 QualType T = Func->getType(); 840 QualType NoProtoType = T; 841 if (const FunctionProtoType *Proto = T->getAsFunctionProtoType()) 842 NoProtoType = Context.getFunctionNoProtoType(Proto->getResultType()); 843 return BuildDeclRefExpr(Func, NoProtoType, Loc, false, false, SS); 844 } 845 } 846 847 return BuildDeclarationNameExpr(Loc, D, HasTrailingLParen, SS, isAddressOfOperand); 848} 849/// \brief Cast member's object to its own class if necessary. 850bool 851Sema::PerformObjectMemberConversion(Expr *&From, NamedDecl *Member) { 852 if (FieldDecl *FD = dyn_cast<FieldDecl>(Member)) 853 if (CXXRecordDecl *RD = 854 dyn_cast<CXXRecordDecl>(FD->getDeclContext())) { 855 QualType DestType = 856 Context.getCanonicalType(Context.getTypeDeclType(RD)); 857 if (DestType->isDependentType() || From->getType()->isDependentType()) 858 return false; 859 QualType FromRecordType = From->getType(); 860 QualType DestRecordType = DestType; 861 if (FromRecordType->getAs<PointerType>()) { 862 DestType = Context.getPointerType(DestType); 863 FromRecordType = FromRecordType->getPointeeType(); 864 } 865 if (!Context.hasSameUnqualifiedType(FromRecordType, DestRecordType) && 866 CheckDerivedToBaseConversion(FromRecordType, 867 DestRecordType, 868 From->getSourceRange().getBegin(), 869 From->getSourceRange())) 870 return true; 871 ImpCastExprToType(From, DestType, CastExpr::CK_DerivedToBase, 872 /*isLvalue=*/true); 873 } 874 return false; 875} 876 877/// \brief Complete semantic analysis for a reference to the given declaration. 878Sema::OwningExprResult 879Sema::BuildDeclarationNameExpr(SourceLocation Loc, NamedDecl *D, 880 bool HasTrailingLParen, 881 const CXXScopeSpec *SS, 882 bool isAddressOfOperand) { 883 assert(D && "Cannot refer to a NULL declaration"); 884 DeclarationName Name = D->getDeclName(); 885 886 // If this is an expression of the form &Class::member, don't build an 887 // implicit member ref, because we want a pointer to the member in general, 888 // not any specific instance's member. 889 if (isAddressOfOperand && SS && !SS->isEmpty() && !HasTrailingLParen) { 890 DeclContext *DC = computeDeclContext(*SS); 891 if (D && isa<CXXRecordDecl>(DC)) { 892 QualType DType; 893 if (FieldDecl *FD = dyn_cast<FieldDecl>(D)) { 894 DType = FD->getType().getNonReferenceType(); 895 } else if (CXXMethodDecl *Method = dyn_cast<CXXMethodDecl>(D)) { 896 DType = Method->getType(); 897 } else if (isa<OverloadedFunctionDecl>(D)) { 898 DType = Context.OverloadTy; 899 } 900 // Could be an inner type. That's diagnosed below, so ignore it here. 901 if (!DType.isNull()) { 902 // The pointer is type- and value-dependent if it points into something 903 // dependent. 904 bool Dependent = DC->isDependentContext(); 905 return BuildDeclRefExpr(D, DType, Loc, Dependent, Dependent, SS); 906 } 907 } 908 } 909 910 // We may have found a field within an anonymous union or struct 911 // (C++ [class.union]). 912 if (FieldDecl *FD = dyn_cast<FieldDecl>(D)) 913 if (cast<RecordDecl>(FD->getDeclContext())->isAnonymousStructOrUnion()) 914 return BuildAnonymousStructUnionMemberReference(Loc, FD); 915 916 if (CXXMethodDecl *MD = dyn_cast<CXXMethodDecl>(CurContext)) { 917 if (!MD->isStatic()) { 918 // C++ [class.mfct.nonstatic]p2: 919 // [...] if name lookup (3.4.1) resolves the name in the 920 // id-expression to a nonstatic nontype member of class X or of 921 // a base class of X, the id-expression is transformed into a 922 // class member access expression (5.2.5) using (*this) (9.3.2) 923 // as the postfix-expression to the left of the '.' operator. 924 DeclContext *Ctx = 0; 925 QualType MemberType; 926 if (FieldDecl *FD = dyn_cast<FieldDecl>(D)) { 927 Ctx = FD->getDeclContext(); 928 MemberType = FD->getType(); 929 930 if (const ReferenceType *RefType = MemberType->getAs<ReferenceType>()) 931 MemberType = RefType->getPointeeType(); 932 else if (!FD->isMutable()) { 933 unsigned combinedQualifiers 934 = MemberType.getCVRQualifiers() | MD->getTypeQualifiers(); 935 MemberType = MemberType.getQualifiedType(combinedQualifiers); 936 } 937 } else if (CXXMethodDecl *Method = dyn_cast<CXXMethodDecl>(D)) { 938 if (!Method->isStatic()) { 939 Ctx = Method->getParent(); 940 MemberType = Method->getType(); 941 } 942 } else if (FunctionTemplateDecl *FunTmpl 943 = dyn_cast<FunctionTemplateDecl>(D)) { 944 if (CXXMethodDecl *Method 945 = dyn_cast<CXXMethodDecl>(FunTmpl->getTemplatedDecl())) { 946 if (!Method->isStatic()) { 947 Ctx = Method->getParent(); 948 MemberType = Context.OverloadTy; 949 } 950 } 951 } else if (OverloadedFunctionDecl *Ovl 952 = dyn_cast<OverloadedFunctionDecl>(D)) { 953 // FIXME: We need an abstraction for iterating over one or more function 954 // templates or functions. This code is far too repetitive! 955 for (OverloadedFunctionDecl::function_iterator 956 Func = Ovl->function_begin(), 957 FuncEnd = Ovl->function_end(); 958 Func != FuncEnd; ++Func) { 959 CXXMethodDecl *DMethod = 0; 960 if (FunctionTemplateDecl *FunTmpl 961 = dyn_cast<FunctionTemplateDecl>(*Func)) 962 DMethod = dyn_cast<CXXMethodDecl>(FunTmpl->getTemplatedDecl()); 963 else 964 DMethod = dyn_cast<CXXMethodDecl>(*Func); 965 966 if (DMethod && !DMethod->isStatic()) { 967 Ctx = DMethod->getDeclContext(); 968 MemberType = Context.OverloadTy; 969 break; 970 } 971 } 972 } 973 974 if (Ctx && Ctx->isRecord()) { 975 QualType CtxType = Context.getTagDeclType(cast<CXXRecordDecl>(Ctx)); 976 QualType ThisType = Context.getTagDeclType(MD->getParent()); 977 if ((Context.getCanonicalType(CtxType) 978 == Context.getCanonicalType(ThisType)) || 979 IsDerivedFrom(ThisType, CtxType)) { 980 // Build the implicit member access expression. 981 Expr *This = new (Context) CXXThisExpr(SourceLocation(), 982 MD->getThisType(Context)); 983 MarkDeclarationReferenced(Loc, D); 984 if (PerformObjectMemberConversion(This, D)) 985 return ExprError(); 986 if (DiagnoseUseOfDecl(D, Loc)) 987 return ExprError(); 988 return Owned(new (Context) MemberExpr(This, true, D, 989 Loc, MemberType)); 990 } 991 } 992 } 993 } 994 995 if (FieldDecl *FD = dyn_cast<FieldDecl>(D)) { 996 if (CXXMethodDecl *MD = dyn_cast<CXXMethodDecl>(CurContext)) { 997 if (MD->isStatic()) 998 // "invalid use of member 'x' in static member function" 999 return ExprError(Diag(Loc,diag::err_invalid_member_use_in_static_method) 1000 << FD->getDeclName()); 1001 } 1002 1003 // Any other ways we could have found the field in a well-formed 1004 // program would have been turned into implicit member expressions 1005 // above. 1006 return ExprError(Diag(Loc, diag::err_invalid_non_static_member_use) 1007 << FD->getDeclName()); 1008 } 1009 1010 if (isa<TypedefDecl>(D)) 1011 return ExprError(Diag(Loc, diag::err_unexpected_typedef) << Name); 1012 if (isa<ObjCInterfaceDecl>(D)) 1013 return ExprError(Diag(Loc, diag::err_unexpected_interface) << Name); 1014 if (isa<NamespaceDecl>(D)) 1015 return ExprError(Diag(Loc, diag::err_unexpected_namespace) << Name); 1016 1017 // Make the DeclRefExpr or BlockDeclRefExpr for the decl. 1018 if (OverloadedFunctionDecl *Ovl = dyn_cast<OverloadedFunctionDecl>(D)) 1019 return BuildDeclRefExpr(Ovl, Context.OverloadTy, Loc, 1020 false, false, SS); 1021 else if (TemplateDecl *Template = dyn_cast<TemplateDecl>(D)) 1022 return BuildDeclRefExpr(Template, Context.OverloadTy, Loc, 1023 false, false, SS); 1024 ValueDecl *VD = cast<ValueDecl>(D); 1025 1026 // Check whether this declaration can be used. Note that we suppress 1027 // this check when we're going to perform argument-dependent lookup 1028 // on this function name, because this might not be the function 1029 // that overload resolution actually selects. 1030 bool ADL = getLangOptions().CPlusPlus && (!SS || !SS->isSet()) && 1031 HasTrailingLParen; 1032 if (!(ADL && isa<FunctionDecl>(VD)) && DiagnoseUseOfDecl(VD, Loc)) 1033 return ExprError(); 1034 1035 // Only create DeclRefExpr's for valid Decl's. 1036 if (VD->isInvalidDecl()) 1037 return ExprError(); 1038 1039 // If the identifier reference is inside a block, and it refers to a value 1040 // that is outside the block, create a BlockDeclRefExpr instead of a 1041 // DeclRefExpr. This ensures the value is treated as a copy-in snapshot when 1042 // the block is formed. 1043 // 1044 // We do not do this for things like enum constants, global variables, etc, 1045 // as they do not get snapshotted. 1046 // 1047 if (CurBlock && ShouldSnapshotBlockValueReference(CurBlock, VD)) { 1048 MarkDeclarationReferenced(Loc, VD); 1049 QualType ExprTy = VD->getType().getNonReferenceType(); 1050 // The BlocksAttr indicates the variable is bound by-reference. 1051 if (VD->getAttr<BlocksAttr>()) 1052 return Owned(new (Context) BlockDeclRefExpr(VD, ExprTy, Loc, true)); 1053 // This is to record that a 'const' was actually synthesize and added. 1054 bool constAdded = !ExprTy.isConstQualified(); 1055 // Variable will be bound by-copy, make it const within the closure. 1056 1057 ExprTy.addConst(); 1058 return Owned(new (Context) BlockDeclRefExpr(VD, ExprTy, Loc, false, 1059 constAdded)); 1060 } 1061 // If this reference is not in a block or if the referenced variable is 1062 // within the block, create a normal DeclRefExpr. 1063 1064 bool TypeDependent = false; 1065 bool ValueDependent = false; 1066 if (getLangOptions().CPlusPlus) { 1067 // C++ [temp.dep.expr]p3: 1068 // An id-expression is type-dependent if it contains: 1069 // - an identifier that was declared with a dependent type, 1070 if (VD->getType()->isDependentType()) 1071 TypeDependent = true; 1072 // - FIXME: a template-id that is dependent, 1073 // - a conversion-function-id that specifies a dependent type, 1074 else if (Name.getNameKind() == DeclarationName::CXXConversionFunctionName && 1075 Name.getCXXNameType()->isDependentType()) 1076 TypeDependent = true; 1077 // - a nested-name-specifier that contains a class-name that 1078 // names a dependent type. 1079 else if (SS && !SS->isEmpty()) { 1080 for (DeclContext *DC = computeDeclContext(*SS); 1081 DC; DC = DC->getParent()) { 1082 // FIXME: could stop early at namespace scope. 1083 if (DC->isRecord()) { 1084 CXXRecordDecl *Record = cast<CXXRecordDecl>(DC); 1085 if (Context.getTypeDeclType(Record)->isDependentType()) { 1086 TypeDependent = true; 1087 break; 1088 } 1089 } 1090 } 1091 } 1092 1093 // C++ [temp.dep.constexpr]p2: 1094 // 1095 // An identifier is value-dependent if it is: 1096 // - a name declared with a dependent type, 1097 if (TypeDependent) 1098 ValueDependent = true; 1099 // - the name of a non-type template parameter, 1100 else if (isa<NonTypeTemplateParmDecl>(VD)) 1101 ValueDependent = true; 1102 // - a constant with integral or enumeration type and is 1103 // initialized with an expression that is value-dependent 1104 else if (const VarDecl *Dcl = dyn_cast<VarDecl>(VD)) { 1105 if (Dcl->getType().getCVRQualifiers() == QualType::Const && 1106 Dcl->getInit()) { 1107 ValueDependent = Dcl->getInit()->isValueDependent(); 1108 } 1109 } 1110 } 1111 1112 return BuildDeclRefExpr(VD, VD->getType().getNonReferenceType(), Loc, 1113 TypeDependent, ValueDependent, SS); 1114} 1115 1116Sema::OwningExprResult Sema::ActOnPredefinedExpr(SourceLocation Loc, 1117 tok::TokenKind Kind) { 1118 PredefinedExpr::IdentType IT; 1119 1120 switch (Kind) { 1121 default: assert(0 && "Unknown simple primary expr!"); 1122 case tok::kw___func__: IT = PredefinedExpr::Func; break; // [C99 6.4.2.2] 1123 case tok::kw___FUNCTION__: IT = PredefinedExpr::Function; break; 1124 case tok::kw___PRETTY_FUNCTION__: IT = PredefinedExpr::PrettyFunction; break; 1125 } 1126 1127 // Pre-defined identifiers are of type char[x], where x is the length of the 1128 // string. 1129 unsigned Length; 1130 if (FunctionDecl *FD = getCurFunctionDecl()) 1131 Length = FD->getIdentifier()->getLength(); 1132 else if (ObjCMethodDecl *MD = getCurMethodDecl()) 1133 Length = MD->getSynthesizedMethodSize(); 1134 else { 1135 Diag(Loc, diag::ext_predef_outside_function); 1136 // __PRETTY_FUNCTION__ -> "top level", the others produce an empty string. 1137 Length = IT == PredefinedExpr::PrettyFunction ? strlen("top level") : 0; 1138 } 1139 1140 1141 llvm::APInt LengthI(32, Length + 1); 1142 QualType ResTy = Context.CharTy.getQualifiedType(QualType::Const); 1143 ResTy = Context.getConstantArrayType(ResTy, LengthI, ArrayType::Normal, 0); 1144 return Owned(new (Context) PredefinedExpr(Loc, ResTy, IT)); 1145} 1146 1147Sema::OwningExprResult Sema::ActOnCharacterConstant(const Token &Tok) { 1148 llvm::SmallString<16> CharBuffer; 1149 CharBuffer.resize(Tok.getLength()); 1150 const char *ThisTokBegin = &CharBuffer[0]; 1151 unsigned ActualLength = PP.getSpelling(Tok, ThisTokBegin); 1152 1153 CharLiteralParser Literal(ThisTokBegin, ThisTokBegin+ActualLength, 1154 Tok.getLocation(), PP); 1155 if (Literal.hadError()) 1156 return ExprError(); 1157 1158 QualType type = getLangOptions().CPlusPlus ? Context.CharTy : Context.IntTy; 1159 1160 return Owned(new (Context) CharacterLiteral(Literal.getValue(), 1161 Literal.isWide(), 1162 type, Tok.getLocation())); 1163} 1164 1165Action::OwningExprResult Sema::ActOnNumericConstant(const Token &Tok) { 1166 // Fast path for a single digit (which is quite common). A single digit 1167 // cannot have a trigraph, escaped newline, radix prefix, or type suffix. 1168 if (Tok.getLength() == 1) { 1169 const char Val = PP.getSpellingOfSingleCharacterNumericConstant(Tok); 1170 unsigned IntSize = Context.Target.getIntWidth(); 1171 return Owned(new (Context) IntegerLiteral(llvm::APInt(IntSize, Val-'0'), 1172 Context.IntTy, Tok.getLocation())); 1173 } 1174 1175 llvm::SmallString<512> IntegerBuffer; 1176 // Add padding so that NumericLiteralParser can overread by one character. 1177 IntegerBuffer.resize(Tok.getLength()+1); 1178 const char *ThisTokBegin = &IntegerBuffer[0]; 1179 1180 // Get the spelling of the token, which eliminates trigraphs, etc. 1181 unsigned ActualLength = PP.getSpelling(Tok, ThisTokBegin); 1182 1183 NumericLiteralParser Literal(ThisTokBegin, ThisTokBegin+ActualLength, 1184 Tok.getLocation(), PP); 1185 if (Literal.hadError) 1186 return ExprError(); 1187 1188 Expr *Res; 1189 1190 if (Literal.isFloatingLiteral()) { 1191 QualType Ty; 1192 if (Literal.isFloat) 1193 Ty = Context.FloatTy; 1194 else if (!Literal.isLong) 1195 Ty = Context.DoubleTy; 1196 else 1197 Ty = Context.LongDoubleTy; 1198 1199 const llvm::fltSemantics &Format = Context.getFloatTypeSemantics(Ty); 1200 1201 // isExact will be set by GetFloatValue(). 1202 bool isExact = false; 1203 llvm::APFloat Val = Literal.GetFloatValue(Format, &isExact); 1204 Res = new (Context) FloatingLiteral(Val, isExact, Ty, Tok.getLocation()); 1205 1206 } else if (!Literal.isIntegerLiteral()) { 1207 return ExprError(); 1208 } else { 1209 QualType Ty; 1210 1211 // long long is a C99 feature. 1212 if (!getLangOptions().C99 && !getLangOptions().CPlusPlus0x && 1213 Literal.isLongLong) 1214 Diag(Tok.getLocation(), diag::ext_longlong); 1215 1216 // Get the value in the widest-possible width. 1217 llvm::APInt ResultVal(Context.Target.getIntMaxTWidth(), 0); 1218 1219 if (Literal.GetIntegerValue(ResultVal)) { 1220 // If this value didn't fit into uintmax_t, warn and force to ull. 1221 Diag(Tok.getLocation(), diag::warn_integer_too_large); 1222 Ty = Context.UnsignedLongLongTy; 1223 assert(Context.getTypeSize(Ty) == ResultVal.getBitWidth() && 1224 "long long is not intmax_t?"); 1225 } else { 1226 // If this value fits into a ULL, try to figure out what else it fits into 1227 // according to the rules of C99 6.4.4.1p5. 1228 1229 // Octal, Hexadecimal, and integers with a U suffix are allowed to 1230 // be an unsigned int. 1231 bool AllowUnsigned = Literal.isUnsigned || Literal.getRadix() != 10; 1232 1233 // Check from smallest to largest, picking the smallest type we can. 1234 unsigned Width = 0; 1235 if (!Literal.isLong && !Literal.isLongLong) { 1236 // Are int/unsigned possibilities? 1237 unsigned IntSize = Context.Target.getIntWidth(); 1238 1239 // Does it fit in a unsigned int? 1240 if (ResultVal.isIntN(IntSize)) { 1241 // Does it fit in a signed int? 1242 if (!Literal.isUnsigned && ResultVal[IntSize-1] == 0) 1243 Ty = Context.IntTy; 1244 else if (AllowUnsigned) 1245 Ty = Context.UnsignedIntTy; 1246 Width = IntSize; 1247 } 1248 } 1249 1250 // Are long/unsigned long possibilities? 1251 if (Ty.isNull() && !Literal.isLongLong) { 1252 unsigned LongSize = Context.Target.getLongWidth(); 1253 1254 // Does it fit in a unsigned long? 1255 if (ResultVal.isIntN(LongSize)) { 1256 // Does it fit in a signed long? 1257 if (!Literal.isUnsigned && ResultVal[LongSize-1] == 0) 1258 Ty = Context.LongTy; 1259 else if (AllowUnsigned) 1260 Ty = Context.UnsignedLongTy; 1261 Width = LongSize; 1262 } 1263 } 1264 1265 // Finally, check long long if needed. 1266 if (Ty.isNull()) { 1267 unsigned LongLongSize = Context.Target.getLongLongWidth(); 1268 1269 // Does it fit in a unsigned long long? 1270 if (ResultVal.isIntN(LongLongSize)) { 1271 // Does it fit in a signed long long? 1272 if (!Literal.isUnsigned && ResultVal[LongLongSize-1] == 0) 1273 Ty = Context.LongLongTy; 1274 else if (AllowUnsigned) 1275 Ty = Context.UnsignedLongLongTy; 1276 Width = LongLongSize; 1277 } 1278 } 1279 1280 // If we still couldn't decide a type, we probably have something that 1281 // does not fit in a signed long long, but has no U suffix. 1282 if (Ty.isNull()) { 1283 Diag(Tok.getLocation(), diag::warn_integer_too_large_for_signed); 1284 Ty = Context.UnsignedLongLongTy; 1285 Width = Context.Target.getLongLongWidth(); 1286 } 1287 1288 if (ResultVal.getBitWidth() != Width) 1289 ResultVal.trunc(Width); 1290 } 1291 Res = new (Context) IntegerLiteral(ResultVal, Ty, Tok.getLocation()); 1292 } 1293 1294 // If this is an imaginary literal, create the ImaginaryLiteral wrapper. 1295 if (Literal.isImaginary) 1296 Res = new (Context) ImaginaryLiteral(Res, 1297 Context.getComplexType(Res->getType())); 1298 1299 return Owned(Res); 1300} 1301 1302Action::OwningExprResult Sema::ActOnParenExpr(SourceLocation L, 1303 SourceLocation R, ExprArg Val) { 1304 Expr *E = Val.takeAs<Expr>(); 1305 assert((E != 0) && "ActOnParenExpr() missing expr"); 1306 return Owned(new (Context) ParenExpr(L, R, E)); 1307} 1308 1309/// The UsualUnaryConversions() function is *not* called by this routine. 1310/// See C99 6.3.2.1p[2-4] for more details. 1311bool Sema::CheckSizeOfAlignOfOperand(QualType exprType, 1312 SourceLocation OpLoc, 1313 const SourceRange &ExprRange, 1314 bool isSizeof) { 1315 if (exprType->isDependentType()) 1316 return false; 1317 1318 // C99 6.5.3.4p1: 1319 if (isa<FunctionType>(exprType)) { 1320 // alignof(function) is allowed as an extension. 1321 if (isSizeof) 1322 Diag(OpLoc, diag::ext_sizeof_function_type) << ExprRange; 1323 return false; 1324 } 1325 1326 // Allow sizeof(void)/alignof(void) as an extension. 1327 if (exprType->isVoidType()) { 1328 Diag(OpLoc, diag::ext_sizeof_void_type) 1329 << (isSizeof ? "sizeof" : "__alignof") << ExprRange; 1330 return false; 1331 } 1332 1333 if (RequireCompleteType(OpLoc, exprType, 1334 isSizeof ? diag::err_sizeof_incomplete_type : 1335 diag::err_alignof_incomplete_type, 1336 ExprRange)) 1337 return true; 1338 1339 // Reject sizeof(interface) and sizeof(interface<proto>) in 64-bit mode. 1340 if (LangOpts.ObjCNonFragileABI && exprType->isObjCInterfaceType()) { 1341 Diag(OpLoc, diag::err_sizeof_nonfragile_interface) 1342 << exprType << isSizeof << ExprRange; 1343 return true; 1344 } 1345 1346 return false; 1347} 1348 1349bool Sema::CheckAlignOfExpr(Expr *E, SourceLocation OpLoc, 1350 const SourceRange &ExprRange) { 1351 E = E->IgnoreParens(); 1352 1353 // alignof decl is always ok. 1354 if (isa<DeclRefExpr>(E)) 1355 return false; 1356 1357 // Cannot know anything else if the expression is dependent. 1358 if (E->isTypeDependent()) 1359 return false; 1360 1361 if (E->getBitField()) { 1362 Diag(OpLoc, diag::err_sizeof_alignof_bitfield) << 1 << ExprRange; 1363 return true; 1364 } 1365 1366 // Alignment of a field access is always okay, so long as it isn't a 1367 // bit-field. 1368 if (MemberExpr *ME = dyn_cast<MemberExpr>(E)) 1369 if (isa<FieldDecl>(ME->getMemberDecl())) 1370 return false; 1371 1372 return CheckSizeOfAlignOfOperand(E->getType(), OpLoc, ExprRange, false); 1373} 1374 1375/// \brief Build a sizeof or alignof expression given a type operand. 1376Action::OwningExprResult 1377Sema::CreateSizeOfAlignOfExpr(QualType T, SourceLocation OpLoc, 1378 bool isSizeOf, SourceRange R) { 1379 if (T.isNull()) 1380 return ExprError(); 1381 1382 if (!T->isDependentType() && 1383 CheckSizeOfAlignOfOperand(T, OpLoc, R, isSizeOf)) 1384 return ExprError(); 1385 1386 // C99 6.5.3.4p4: the type (an unsigned integer type) is size_t. 1387 return Owned(new (Context) SizeOfAlignOfExpr(isSizeOf, T, 1388 Context.getSizeType(), OpLoc, 1389 R.getEnd())); 1390} 1391 1392/// \brief Build a sizeof or alignof expression given an expression 1393/// operand. 1394Action::OwningExprResult 1395Sema::CreateSizeOfAlignOfExpr(Expr *E, SourceLocation OpLoc, 1396 bool isSizeOf, SourceRange R) { 1397 // Verify that the operand is valid. 1398 bool isInvalid = false; 1399 if (E->isTypeDependent()) { 1400 // Delay type-checking for type-dependent expressions. 1401 } else if (!isSizeOf) { 1402 isInvalid = CheckAlignOfExpr(E, OpLoc, R); 1403 } else if (E->getBitField()) { // C99 6.5.3.4p1. 1404 Diag(OpLoc, diag::err_sizeof_alignof_bitfield) << 0; 1405 isInvalid = true; 1406 } else { 1407 isInvalid = CheckSizeOfAlignOfOperand(E->getType(), OpLoc, R, true); 1408 } 1409 1410 if (isInvalid) 1411 return ExprError(); 1412 1413 // C99 6.5.3.4p4: the type (an unsigned integer type) is size_t. 1414 return Owned(new (Context) SizeOfAlignOfExpr(isSizeOf, E, 1415 Context.getSizeType(), OpLoc, 1416 R.getEnd())); 1417} 1418 1419/// ActOnSizeOfAlignOfExpr - Handle @c sizeof(type) and @c sizeof @c expr and 1420/// the same for @c alignof and @c __alignof 1421/// Note that the ArgRange is invalid if isType is false. 1422Action::OwningExprResult 1423Sema::ActOnSizeOfAlignOfExpr(SourceLocation OpLoc, bool isSizeof, bool isType, 1424 void *TyOrEx, const SourceRange &ArgRange) { 1425 // If error parsing type, ignore. 1426 if (TyOrEx == 0) return ExprError(); 1427 1428 if (isType) { 1429 // FIXME: Preserve type source info. 1430 QualType ArgTy = GetTypeFromParser(TyOrEx); 1431 return CreateSizeOfAlignOfExpr(ArgTy, OpLoc, isSizeof, ArgRange); 1432 } 1433 1434 // Get the end location. 1435 Expr *ArgEx = (Expr *)TyOrEx; 1436 Action::OwningExprResult Result 1437 = CreateSizeOfAlignOfExpr(ArgEx, OpLoc, isSizeof, ArgEx->getSourceRange()); 1438 1439 if (Result.isInvalid()) 1440 DeleteExpr(ArgEx); 1441 1442 return move(Result); 1443} 1444 1445QualType Sema::CheckRealImagOperand(Expr *&V, SourceLocation Loc, bool isReal) { 1446 if (V->isTypeDependent()) 1447 return Context.DependentTy; 1448 1449 // These operators return the element type of a complex type. 1450 if (const ComplexType *CT = V->getType()->getAsComplexType()) 1451 return CT->getElementType(); 1452 1453 // Otherwise they pass through real integer and floating point types here. 1454 if (V->getType()->isArithmeticType()) 1455 return V->getType(); 1456 1457 // Reject anything else. 1458 Diag(Loc, diag::err_realimag_invalid_type) << V->getType() 1459 << (isReal ? "__real" : "__imag"); 1460 return QualType(); 1461} 1462 1463 1464 1465Action::OwningExprResult 1466Sema::ActOnPostfixUnaryOp(Scope *S, SourceLocation OpLoc, 1467 tok::TokenKind Kind, ExprArg Input) { 1468 // Since this might be a postfix expression, get rid of ParenListExprs. 1469 Input = MaybeConvertParenListExprToParenExpr(S, move(Input)); 1470 Expr *Arg = (Expr *)Input.get(); 1471 1472 UnaryOperator::Opcode Opc; 1473 switch (Kind) { 1474 default: assert(0 && "Unknown unary op!"); 1475 case tok::plusplus: Opc = UnaryOperator::PostInc; break; 1476 case tok::minusminus: Opc = UnaryOperator::PostDec; break; 1477 } 1478 1479 if (getLangOptions().CPlusPlus && 1480 (Arg->getType()->isRecordType() || Arg->getType()->isEnumeralType())) { 1481 // Which overloaded operator? 1482 OverloadedOperatorKind OverOp = 1483 (Opc == UnaryOperator::PostInc)? OO_PlusPlus : OO_MinusMinus; 1484 1485 // C++ [over.inc]p1: 1486 // 1487 // [...] If the function is a member function with one 1488 // parameter (which shall be of type int) or a non-member 1489 // function with two parameters (the second of which shall be 1490 // of type int), it defines the postfix increment operator ++ 1491 // for objects of that type. When the postfix increment is 1492 // called as a result of using the ++ operator, the int 1493 // argument will have value zero. 1494 Expr *Args[2] = { 1495 Arg, 1496 new (Context) IntegerLiteral(llvm::APInt(Context.Target.getIntWidth(), 0, 1497 /*isSigned=*/true), Context.IntTy, SourceLocation()) 1498 }; 1499 1500 // Build the candidate set for overloading 1501 OverloadCandidateSet CandidateSet; 1502 AddOperatorCandidates(OverOp, S, OpLoc, Args, 2, CandidateSet); 1503 1504 // Perform overload resolution. 1505 OverloadCandidateSet::iterator Best; 1506 switch (BestViableFunction(CandidateSet, OpLoc, Best)) { 1507 case OR_Success: { 1508 // We found a built-in operator or an overloaded operator. 1509 FunctionDecl *FnDecl = Best->Function; 1510 1511 if (FnDecl) { 1512 // We matched an overloaded operator. Build a call to that 1513 // operator. 1514 1515 // Convert the arguments. 1516 if (CXXMethodDecl *Method = dyn_cast<CXXMethodDecl>(FnDecl)) { 1517 if (PerformObjectArgumentInitialization(Arg, Method)) 1518 return ExprError(); 1519 } else { 1520 // Convert the arguments. 1521 if (PerformCopyInitialization(Arg, 1522 FnDecl->getParamDecl(0)->getType(), 1523 "passing")) 1524 return ExprError(); 1525 } 1526 1527 // Determine the result type 1528 QualType ResultTy 1529 = FnDecl->getType()->getAsFunctionType()->getResultType(); 1530 ResultTy = ResultTy.getNonReferenceType(); 1531 1532 // Build the actual expression node. 1533 Expr *FnExpr = new (Context) DeclRefExpr(FnDecl, FnDecl->getType(), 1534 SourceLocation()); 1535 UsualUnaryConversions(FnExpr); 1536 1537 Input.release(); 1538 Args[0] = Arg; 1539 return Owned(new (Context) CXXOperatorCallExpr(Context, OverOp, FnExpr, 1540 Args, 2, ResultTy, 1541 OpLoc)); 1542 } else { 1543 // We matched a built-in operator. Convert the arguments, then 1544 // break out so that we will build the appropriate built-in 1545 // operator node. 1546 if (PerformCopyInitialization(Arg, Best->BuiltinTypes.ParamTypes[0], 1547 "passing")) 1548 return ExprError(); 1549 1550 break; 1551 } 1552 } 1553 1554 case OR_No_Viable_Function: 1555 // No viable function; fall through to handling this as a 1556 // built-in operator, which will produce an error message for us. 1557 break; 1558 1559 case OR_Ambiguous: 1560 Diag(OpLoc, diag::err_ovl_ambiguous_oper) 1561 << UnaryOperator::getOpcodeStr(Opc) 1562 << Arg->getSourceRange(); 1563 PrintOverloadCandidates(CandidateSet, /*OnlyViable=*/true); 1564 return ExprError(); 1565 1566 case OR_Deleted: 1567 Diag(OpLoc, diag::err_ovl_deleted_oper) 1568 << Best->Function->isDeleted() 1569 << UnaryOperator::getOpcodeStr(Opc) 1570 << Arg->getSourceRange(); 1571 PrintOverloadCandidates(CandidateSet, /*OnlyViable=*/true); 1572 return ExprError(); 1573 } 1574 1575 // Either we found no viable overloaded operator or we matched a 1576 // built-in operator. In either case, fall through to trying to 1577 // build a built-in operation. 1578 } 1579 1580 Input.release(); 1581 Input = Arg; 1582 return CreateBuiltinUnaryOp(OpLoc, Opc, move(Input)); 1583} 1584 1585Action::OwningExprResult 1586Sema::ActOnArraySubscriptExpr(Scope *S, ExprArg Base, SourceLocation LLoc, 1587 ExprArg Idx, SourceLocation RLoc) { 1588 // Since this might be a postfix expression, get rid of ParenListExprs. 1589 Base = MaybeConvertParenListExprToParenExpr(S, move(Base)); 1590 1591 Expr *LHSExp = static_cast<Expr*>(Base.get()), 1592 *RHSExp = static_cast<Expr*>(Idx.get()); 1593 1594 if (getLangOptions().CPlusPlus && 1595 (LHSExp->isTypeDependent() || RHSExp->isTypeDependent())) { 1596 Base.release(); 1597 Idx.release(); 1598 return Owned(new (Context) ArraySubscriptExpr(LHSExp, RHSExp, 1599 Context.DependentTy, RLoc)); 1600 } 1601 1602 if (getLangOptions().CPlusPlus && 1603 (LHSExp->getType()->isRecordType() || 1604 LHSExp->getType()->isEnumeralType() || 1605 RHSExp->getType()->isRecordType() || 1606 RHSExp->getType()->isEnumeralType())) { 1607 // Add the appropriate overloaded operators (C++ [over.match.oper]) 1608 // to the candidate set. 1609 OverloadCandidateSet CandidateSet; 1610 Expr *Args[2] = { LHSExp, RHSExp }; 1611 AddOperatorCandidates(OO_Subscript, S, LLoc, Args, 2, CandidateSet, 1612 SourceRange(LLoc, RLoc)); 1613 1614 // Perform overload resolution. 1615 OverloadCandidateSet::iterator Best; 1616 switch (BestViableFunction(CandidateSet, LLoc, Best)) { 1617 case OR_Success: { 1618 // We found a built-in operator or an overloaded operator. 1619 FunctionDecl *FnDecl = Best->Function; 1620 1621 if (FnDecl) { 1622 // We matched an overloaded operator. Build a call to that 1623 // operator. 1624 1625 // Convert the arguments. 1626 if (CXXMethodDecl *Method = dyn_cast<CXXMethodDecl>(FnDecl)) { 1627 if (PerformObjectArgumentInitialization(LHSExp, Method) || 1628 PerformCopyInitialization(RHSExp, 1629 FnDecl->getParamDecl(0)->getType(), 1630 "passing")) 1631 return ExprError(); 1632 } else { 1633 // Convert the arguments. 1634 if (PerformCopyInitialization(LHSExp, 1635 FnDecl->getParamDecl(0)->getType(), 1636 "passing") || 1637 PerformCopyInitialization(RHSExp, 1638 FnDecl->getParamDecl(1)->getType(), 1639 "passing")) 1640 return ExprError(); 1641 } 1642 1643 // Determine the result type 1644 QualType ResultTy 1645 = FnDecl->getType()->getAsFunctionType()->getResultType(); 1646 ResultTy = ResultTy.getNonReferenceType(); 1647 1648 // Build the actual expression node. 1649 Expr *FnExpr = new (Context) DeclRefExpr(FnDecl, FnDecl->getType(), 1650 SourceLocation()); 1651 UsualUnaryConversions(FnExpr); 1652 1653 Base.release(); 1654 Idx.release(); 1655 Args[0] = LHSExp; 1656 Args[1] = RHSExp; 1657 return Owned(new (Context) CXXOperatorCallExpr(Context, OO_Subscript, 1658 FnExpr, Args, 2, 1659 ResultTy, LLoc)); 1660 } else { 1661 // We matched a built-in operator. Convert the arguments, then 1662 // break out so that we will build the appropriate built-in 1663 // operator node. 1664 if (PerformCopyInitialization(LHSExp, Best->BuiltinTypes.ParamTypes[0], 1665 "passing") || 1666 PerformCopyInitialization(RHSExp, Best->BuiltinTypes.ParamTypes[1], 1667 "passing")) 1668 return ExprError(); 1669 1670 break; 1671 } 1672 } 1673 1674 case OR_No_Viable_Function: 1675 // No viable function; fall through to handling this as a 1676 // built-in operator, which will produce an error message for us. 1677 break; 1678 1679 case OR_Ambiguous: 1680 Diag(LLoc, diag::err_ovl_ambiguous_oper) 1681 << "[]" 1682 << LHSExp->getSourceRange() << RHSExp->getSourceRange(); 1683 PrintOverloadCandidates(CandidateSet, /*OnlyViable=*/true); 1684 return ExprError(); 1685 1686 case OR_Deleted: 1687 Diag(LLoc, diag::err_ovl_deleted_oper) 1688 << Best->Function->isDeleted() 1689 << "[]" 1690 << LHSExp->getSourceRange() << RHSExp->getSourceRange(); 1691 PrintOverloadCandidates(CandidateSet, /*OnlyViable=*/true); 1692 return ExprError(); 1693 } 1694 1695 // Either we found no viable overloaded operator or we matched a 1696 // built-in operator. In either case, fall through to trying to 1697 // build a built-in operation. 1698 } 1699 1700 // Perform default conversions. 1701 DefaultFunctionArrayConversion(LHSExp); 1702 DefaultFunctionArrayConversion(RHSExp); 1703 1704 QualType LHSTy = LHSExp->getType(), RHSTy = RHSExp->getType(); 1705 1706 // C99 6.5.2.1p2: the expression e1[e2] is by definition precisely equivalent 1707 // to the expression *((e1)+(e2)). This means the array "Base" may actually be 1708 // in the subscript position. As a result, we need to derive the array base 1709 // and index from the expression types. 1710 Expr *BaseExpr, *IndexExpr; 1711 QualType ResultType; 1712 if (LHSTy->isDependentType() || RHSTy->isDependentType()) { 1713 BaseExpr = LHSExp; 1714 IndexExpr = RHSExp; 1715 ResultType = Context.DependentTy; 1716 } else if (const PointerType *PTy = LHSTy->getAs<PointerType>()) { 1717 BaseExpr = LHSExp; 1718 IndexExpr = RHSExp; 1719 ResultType = PTy->getPointeeType(); 1720 } else if (const PointerType *PTy = RHSTy->getAs<PointerType>()) { 1721 // Handle the uncommon case of "123[Ptr]". 1722 BaseExpr = RHSExp; 1723 IndexExpr = LHSExp; 1724 ResultType = PTy->getPointeeType(); 1725 } else if (const ObjCObjectPointerType *PTy = 1726 LHSTy->getAsObjCObjectPointerType()) { 1727 BaseExpr = LHSExp; 1728 IndexExpr = RHSExp; 1729 ResultType = PTy->getPointeeType(); 1730 } else if (const ObjCObjectPointerType *PTy = 1731 RHSTy->getAsObjCObjectPointerType()) { 1732 // Handle the uncommon case of "123[Ptr]". 1733 BaseExpr = RHSExp; 1734 IndexExpr = LHSExp; 1735 ResultType = PTy->getPointeeType(); 1736 } else if (const VectorType *VTy = LHSTy->getAsVectorType()) { 1737 BaseExpr = LHSExp; // vectors: V[123] 1738 IndexExpr = RHSExp; 1739 1740 // FIXME: need to deal with const... 1741 ResultType = VTy->getElementType(); 1742 } else if (LHSTy->isArrayType()) { 1743 // If we see an array that wasn't promoted by 1744 // DefaultFunctionArrayConversion, it must be an array that 1745 // wasn't promoted because of the C90 rule that doesn't 1746 // allow promoting non-lvalue arrays. Warn, then 1747 // force the promotion here. 1748 Diag(LHSExp->getLocStart(), diag::ext_subscript_non_lvalue) << 1749 LHSExp->getSourceRange(); 1750 ImpCastExprToType(LHSExp, Context.getArrayDecayedType(LHSTy)); 1751 LHSTy = LHSExp->getType(); 1752 1753 BaseExpr = LHSExp; 1754 IndexExpr = RHSExp; 1755 ResultType = LHSTy->getAs<PointerType>()->getPointeeType(); 1756 } else if (RHSTy->isArrayType()) { 1757 // Same as previous, except for 123[f().a] case 1758 Diag(RHSExp->getLocStart(), diag::ext_subscript_non_lvalue) << 1759 RHSExp->getSourceRange(); 1760 ImpCastExprToType(RHSExp, Context.getArrayDecayedType(RHSTy)); 1761 RHSTy = RHSExp->getType(); 1762 1763 BaseExpr = RHSExp; 1764 IndexExpr = LHSExp; 1765 ResultType = RHSTy->getAs<PointerType>()->getPointeeType(); 1766 } else { 1767 return ExprError(Diag(LLoc, diag::err_typecheck_subscript_value) 1768 << LHSExp->getSourceRange() << RHSExp->getSourceRange()); 1769 } 1770 // C99 6.5.2.1p1 1771 if (!(IndexExpr->getType()->isIntegerType() && 1772 IndexExpr->getType()->isScalarType()) && !IndexExpr->isTypeDependent()) 1773 return ExprError(Diag(LLoc, diag::err_typecheck_subscript_not_integer) 1774 << IndexExpr->getSourceRange()); 1775 1776 // C99 6.5.2.1p1: "shall have type "pointer to *object* type". Similarly, 1777 // C++ [expr.sub]p1: The type "T" shall be a completely-defined object 1778 // type. Note that Functions are not objects, and that (in C99 parlance) 1779 // incomplete types are not object types. 1780 if (ResultType->isFunctionType()) { 1781 Diag(BaseExpr->getLocStart(), diag::err_subscript_function_type) 1782 << ResultType << BaseExpr->getSourceRange(); 1783 return ExprError(); 1784 } 1785 1786 if (!ResultType->isDependentType() && 1787 RequireCompleteType(LLoc, ResultType, diag::err_subscript_incomplete_type, 1788 BaseExpr->getSourceRange())) 1789 return ExprError(); 1790 1791 // Diagnose bad cases where we step over interface counts. 1792 if (ResultType->isObjCInterfaceType() && LangOpts.ObjCNonFragileABI) { 1793 Diag(LLoc, diag::err_subscript_nonfragile_interface) 1794 << ResultType << BaseExpr->getSourceRange(); 1795 return ExprError(); 1796 } 1797 1798 Base.release(); 1799 Idx.release(); 1800 return Owned(new (Context) ArraySubscriptExpr(LHSExp, RHSExp, 1801 ResultType, RLoc)); 1802} 1803 1804QualType Sema:: 1805CheckExtVectorComponent(QualType baseType, SourceLocation OpLoc, 1806 IdentifierInfo &CompName, SourceLocation CompLoc) { 1807 const ExtVectorType *vecType = baseType->getAsExtVectorType(); 1808 1809 // The vector accessor can't exceed the number of elements. 1810 const char *compStr = CompName.getName(); 1811 1812 // This flag determines whether or not the component is one of the four 1813 // special names that indicate a subset of exactly half the elements are 1814 // to be selected. 1815 bool HalvingSwizzle = false; 1816 1817 // This flag determines whether or not CompName has an 's' char prefix, 1818 // indicating that it is a string of hex values to be used as vector indices. 1819 bool HexSwizzle = *compStr == 's' || *compStr == 'S'; 1820 1821 // Check that we've found one of the special components, or that the component 1822 // names must come from the same set. 1823 if (!strcmp(compStr, "hi") || !strcmp(compStr, "lo") || 1824 !strcmp(compStr, "even") || !strcmp(compStr, "odd")) { 1825 HalvingSwizzle = true; 1826 } else if (vecType->getPointAccessorIdx(*compStr) != -1) { 1827 do 1828 compStr++; 1829 while (*compStr && vecType->getPointAccessorIdx(*compStr) != -1); 1830 } else if (HexSwizzle || vecType->getNumericAccessorIdx(*compStr) != -1) { 1831 do 1832 compStr++; 1833 while (*compStr && vecType->getNumericAccessorIdx(*compStr) != -1); 1834 } 1835 1836 if (!HalvingSwizzle && *compStr) { 1837 // We didn't get to the end of the string. This means the component names 1838 // didn't come from the same set *or* we encountered an illegal name. 1839 Diag(OpLoc, diag::err_ext_vector_component_name_illegal) 1840 << std::string(compStr,compStr+1) << SourceRange(CompLoc); 1841 return QualType(); 1842 } 1843 1844 // Ensure no component accessor exceeds the width of the vector type it 1845 // operates on. 1846 if (!HalvingSwizzle) { 1847 compStr = CompName.getName(); 1848 1849 if (HexSwizzle) 1850 compStr++; 1851 1852 while (*compStr) { 1853 if (!vecType->isAccessorWithinNumElements(*compStr++)) { 1854 Diag(OpLoc, diag::err_ext_vector_component_exceeds_length) 1855 << baseType << SourceRange(CompLoc); 1856 return QualType(); 1857 } 1858 } 1859 } 1860 1861 // If this is a halving swizzle, verify that the base type has an even 1862 // number of elements. 1863 if (HalvingSwizzle && (vecType->getNumElements() & 1U)) { 1864 Diag(OpLoc, diag::err_ext_vector_component_requires_even) 1865 << baseType << SourceRange(CompLoc); 1866 return QualType(); 1867 } 1868 1869 // The component accessor looks fine - now we need to compute the actual type. 1870 // The vector type is implied by the component accessor. For example, 1871 // vec4.b is a float, vec4.xy is a vec2, vec4.rgb is a vec3, etc. 1872 // vec4.s0 is a float, vec4.s23 is a vec3, etc. 1873 // vec4.hi, vec4.lo, vec4.e, and vec4.o all return vec2. 1874 unsigned CompSize = HalvingSwizzle ? vecType->getNumElements() / 2 1875 : CompName.getLength(); 1876 if (HexSwizzle) 1877 CompSize--; 1878 1879 if (CompSize == 1) 1880 return vecType->getElementType(); 1881 1882 QualType VT = Context.getExtVectorType(vecType->getElementType(), CompSize); 1883 // Now look up the TypeDefDecl from the vector type. Without this, 1884 // diagostics look bad. We want extended vector types to appear built-in. 1885 for (unsigned i = 0, E = ExtVectorDecls.size(); i != E; ++i) { 1886 if (ExtVectorDecls[i]->getUnderlyingType() == VT) 1887 return Context.getTypedefType(ExtVectorDecls[i]); 1888 } 1889 return VT; // should never get here (a typedef type should always be found). 1890} 1891 1892static Decl *FindGetterNameDeclFromProtocolList(const ObjCProtocolDecl*PDecl, 1893 IdentifierInfo &Member, 1894 const Selector &Sel, 1895 ASTContext &Context) { 1896 1897 if (ObjCPropertyDecl *PD = PDecl->FindPropertyDeclaration(&Member)) 1898 return PD; 1899 if (ObjCMethodDecl *OMD = PDecl->getInstanceMethod(Sel)) 1900 return OMD; 1901 1902 for (ObjCProtocolDecl::protocol_iterator I = PDecl->protocol_begin(), 1903 E = PDecl->protocol_end(); I != E; ++I) { 1904 if (Decl *D = FindGetterNameDeclFromProtocolList(*I, Member, Sel, 1905 Context)) 1906 return D; 1907 } 1908 return 0; 1909} 1910 1911static Decl *FindGetterNameDecl(const ObjCObjectPointerType *QIdTy, 1912 IdentifierInfo &Member, 1913 const Selector &Sel, 1914 ASTContext &Context) { 1915 // Check protocols on qualified interfaces. 1916 Decl *GDecl = 0; 1917 for (ObjCObjectPointerType::qual_iterator I = QIdTy->qual_begin(), 1918 E = QIdTy->qual_end(); I != E; ++I) { 1919 if (ObjCPropertyDecl *PD = (*I)->FindPropertyDeclaration(&Member)) { 1920 GDecl = PD; 1921 break; 1922 } 1923 // Also must look for a getter name which uses property syntax. 1924 if (ObjCMethodDecl *OMD = (*I)->getInstanceMethod(Sel)) { 1925 GDecl = OMD; 1926 break; 1927 } 1928 } 1929 if (!GDecl) { 1930 for (ObjCObjectPointerType::qual_iterator I = QIdTy->qual_begin(), 1931 E = QIdTy->qual_end(); I != E; ++I) { 1932 // Search in the protocol-qualifier list of current protocol. 1933 GDecl = FindGetterNameDeclFromProtocolList(*I, Member, Sel, Context); 1934 if (GDecl) 1935 return GDecl; 1936 } 1937 } 1938 return GDecl; 1939} 1940 1941/// FindMethodInNestedImplementations - Look up a method in current and 1942/// all base class implementations. 1943/// 1944ObjCMethodDecl *Sema::FindMethodInNestedImplementations( 1945 const ObjCInterfaceDecl *IFace, 1946 const Selector &Sel) { 1947 ObjCMethodDecl *Method = 0; 1948 if (ObjCImplementationDecl *ImpDecl = IFace->getImplementation()) 1949 Method = ImpDecl->getInstanceMethod(Sel); 1950 1951 if (!Method && IFace->getSuperClass()) 1952 return FindMethodInNestedImplementations(IFace->getSuperClass(), Sel); 1953 return Method; 1954} 1955 1956Action::OwningExprResult 1957Sema::ActOnMemberReferenceExpr(Scope *S, ExprArg Base, SourceLocation OpLoc, 1958 tok::TokenKind OpKind, SourceLocation MemberLoc, 1959 IdentifierInfo &Member, 1960 DeclPtrTy ObjCImpDecl, const CXXScopeSpec *SS) { 1961 // FIXME: handle the CXXScopeSpec for proper lookup of qualified-ids 1962 if (SS && SS->isInvalid()) 1963 return ExprError(); 1964 1965 // Since this might be a postfix expression, get rid of ParenListExprs. 1966 Base = MaybeConvertParenListExprToParenExpr(S, move(Base)); 1967 1968 Expr *BaseExpr = Base.takeAs<Expr>(); 1969 assert(BaseExpr && "no record expression"); 1970 1971 // Perform default conversions. 1972 DefaultFunctionArrayConversion(BaseExpr); 1973 1974 QualType BaseType = BaseExpr->getType(); 1975 // If this is an Objective-C pseudo-builtin and a definition is provided then 1976 // use that. 1977 if (BaseType->isObjCIdType()) { 1978 // We have an 'id' type. Rather than fall through, we check if this 1979 // is a reference to 'isa'. 1980 if (BaseType != Context.ObjCIdRedefinitionType) { 1981 BaseType = Context.ObjCIdRedefinitionType; 1982 ImpCastExprToType(BaseExpr, BaseType); 1983 } 1984 } else if (BaseType->isObjCClassType() && 1985 BaseType != Context.ObjCClassRedefinitionType) { 1986 BaseType = Context.ObjCClassRedefinitionType; 1987 ImpCastExprToType(BaseExpr, BaseType); 1988 } 1989 assert(!BaseType.isNull() && "no type for member expression"); 1990 1991 // Get the type being accessed in BaseType. If this is an arrow, the BaseExpr 1992 // must have pointer type, and the accessed type is the pointee. 1993 if (OpKind == tok::arrow) { 1994 if (BaseType->isDependentType()) 1995 return Owned(new (Context) CXXUnresolvedMemberExpr(Context, 1996 BaseExpr, true, 1997 OpLoc, 1998 DeclarationName(&Member), 1999 MemberLoc)); 2000 else if (const PointerType *PT = BaseType->getAs<PointerType>()) 2001 BaseType = PT->getPointeeType(); 2002 else if (BaseType->isObjCObjectPointerType()) 2003 ; 2004 else 2005 return ExprError(Diag(MemberLoc, 2006 diag::err_typecheck_member_reference_arrow) 2007 << BaseType << BaseExpr->getSourceRange()); 2008 } else { 2009 if (BaseType->isDependentType()) { 2010 // Require that the base type isn't a pointer type 2011 // (so we'll report an error for) 2012 // T* t; 2013 // t.f; 2014 // 2015 // In Obj-C++, however, the above expression is valid, since it could be 2016 // accessing the 'f' property if T is an Obj-C interface. The extra check 2017 // allows this, while still reporting an error if T is a struct pointer. 2018 const PointerType *PT = BaseType->getAs<PointerType>(); 2019 2020 if (!PT || (getLangOptions().ObjC1 && 2021 !PT->getPointeeType()->isRecordType())) 2022 return Owned(new (Context) CXXUnresolvedMemberExpr(Context, 2023 BaseExpr, false, 2024 OpLoc, 2025 DeclarationName(&Member), 2026 MemberLoc)); 2027 } 2028 } 2029 2030 // Handle field access to simple records. This also handles access to fields 2031 // of the ObjC 'id' struct. 2032 if (const RecordType *RTy = BaseType->getAs<RecordType>()) { 2033 RecordDecl *RDecl = RTy->getDecl(); 2034 if (RequireCompleteType(OpLoc, BaseType, 2035 diag::err_typecheck_incomplete_tag, 2036 BaseExpr->getSourceRange())) 2037 return ExprError(); 2038 2039 DeclContext *DC = RDecl; 2040 if (SS && SS->isSet()) { 2041 // If the member name was a qualified-id, look into the 2042 // nested-name-specifier. 2043 DC = computeDeclContext(*SS, false); 2044 2045 // FIXME: If DC is not computable, we should build a 2046 // CXXUnresolvedMemberExpr. 2047 assert(DC && "Cannot handle non-computable dependent contexts in lookup"); 2048 } 2049 2050 // The record definition is complete, now make sure the member is valid. 2051 LookupResult Result 2052 = LookupQualifiedName(DC, DeclarationName(&Member), 2053 LookupMemberName, false); 2054 2055 if (SS && SS->isSet()) { 2056 QualType BaseTypeCanon 2057 = Context.getCanonicalType(BaseType).getUnqualifiedType(); 2058 QualType MemberTypeCanon 2059 = Context.getCanonicalType( 2060 Context.getTypeDeclType( 2061 dyn_cast<TypeDecl>(Result.getAsDecl()->getDeclContext()))); 2062 2063 if (BaseTypeCanon != MemberTypeCanon && 2064 !IsDerivedFrom(BaseTypeCanon, MemberTypeCanon)) 2065 return ExprError(Diag(SS->getBeginLoc(), 2066 diag::err_not_direct_base_or_virtual) 2067 << MemberTypeCanon << BaseTypeCanon); 2068 } 2069 2070 if (!Result) 2071 return ExprError(Diag(MemberLoc, diag::err_typecheck_no_member) 2072 << &Member << BaseExpr->getSourceRange()); 2073 if (Result.isAmbiguous()) { 2074 DiagnoseAmbiguousLookup(Result, DeclarationName(&Member), 2075 MemberLoc, BaseExpr->getSourceRange()); 2076 return ExprError(); 2077 } 2078 2079 NamedDecl *MemberDecl = Result; 2080 2081 // If the decl being referenced had an error, return an error for this 2082 // sub-expr without emitting another error, in order to avoid cascading 2083 // error cases. 2084 if (MemberDecl->isInvalidDecl()) 2085 return ExprError(); 2086 2087 // Check the use of this field 2088 if (DiagnoseUseOfDecl(MemberDecl, MemberLoc)) 2089 return ExprError(); 2090 2091 if (FieldDecl *FD = dyn_cast<FieldDecl>(MemberDecl)) { 2092 // We may have found a field within an anonymous union or struct 2093 // (C++ [class.union]). 2094 if (cast<RecordDecl>(FD->getDeclContext())->isAnonymousStructOrUnion()) 2095 return BuildAnonymousStructUnionMemberReference(MemberLoc, FD, 2096 BaseExpr, OpLoc); 2097 2098 // Figure out the type of the member; see C99 6.5.2.3p3, C++ [expr.ref] 2099 QualType MemberType = FD->getType(); 2100 if (const ReferenceType *Ref = MemberType->getAs<ReferenceType>()) 2101 MemberType = Ref->getPointeeType(); 2102 else { 2103 unsigned BaseAddrSpace = BaseType.getAddressSpace(); 2104 unsigned combinedQualifiers = 2105 MemberType.getCVRQualifiers() | BaseType.getCVRQualifiers(); 2106 if (FD->isMutable()) 2107 combinedQualifiers &= ~QualType::Const; 2108 MemberType = MemberType.getQualifiedType(combinedQualifiers); 2109 if (BaseAddrSpace != MemberType.getAddressSpace()) 2110 MemberType = Context.getAddrSpaceQualType(MemberType, BaseAddrSpace); 2111 } 2112 2113 MarkDeclarationReferenced(MemberLoc, FD); 2114 if (PerformObjectMemberConversion(BaseExpr, FD)) 2115 return ExprError(); 2116 return Owned(new (Context) MemberExpr(BaseExpr, OpKind == tok::arrow, FD, 2117 MemberLoc, MemberType)); 2118 } 2119 2120 if (VarDecl *Var = dyn_cast<VarDecl>(MemberDecl)) { 2121 MarkDeclarationReferenced(MemberLoc, MemberDecl); 2122 return Owned(new (Context) MemberExpr(BaseExpr, OpKind == tok::arrow, 2123 Var, MemberLoc, 2124 Var->getType().getNonReferenceType())); 2125 } 2126 if (FunctionDecl *MemberFn = dyn_cast<FunctionDecl>(MemberDecl)) { 2127 MarkDeclarationReferenced(MemberLoc, MemberDecl); 2128 return Owned(new (Context) MemberExpr(BaseExpr, OpKind == tok::arrow, 2129 MemberFn, MemberLoc, 2130 MemberFn->getType())); 2131 } 2132 if (FunctionTemplateDecl *FunTmpl 2133 = dyn_cast<FunctionTemplateDecl>(MemberDecl)) { 2134 MarkDeclarationReferenced(MemberLoc, MemberDecl); 2135 return Owned(new (Context) MemberExpr(BaseExpr, OpKind == tok::arrow, 2136 FunTmpl, MemberLoc, 2137 Context.OverloadTy)); 2138 } 2139 if (OverloadedFunctionDecl *Ovl 2140 = dyn_cast<OverloadedFunctionDecl>(MemberDecl)) 2141 return Owned(new (Context) MemberExpr(BaseExpr, OpKind == tok::arrow, Ovl, 2142 MemberLoc, Context.OverloadTy)); 2143 if (EnumConstantDecl *Enum = dyn_cast<EnumConstantDecl>(MemberDecl)) { 2144 MarkDeclarationReferenced(MemberLoc, MemberDecl); 2145 return Owned(new (Context) MemberExpr(BaseExpr, OpKind == tok::arrow, 2146 Enum, MemberLoc, Enum->getType())); 2147 } 2148 if (isa<TypeDecl>(MemberDecl)) 2149 return ExprError(Diag(MemberLoc,diag::err_typecheck_member_reference_type) 2150 << DeclarationName(&Member) << int(OpKind == tok::arrow)); 2151 2152 // We found a declaration kind that we didn't expect. This is a 2153 // generic error message that tells the user that she can't refer 2154 // to this member with '.' or '->'. 2155 return ExprError(Diag(MemberLoc, 2156 diag::err_typecheck_member_reference_unknown) 2157 << DeclarationName(&Member) << int(OpKind == tok::arrow)); 2158 } 2159 2160 // Handle properties on ObjC 'Class' types. 2161 if (OpKind == tok::period && BaseType->isObjCClassType()) { 2162 // Also must look for a getter name which uses property syntax. 2163 Selector Sel = PP.getSelectorTable().getNullarySelector(&Member); 2164 if (ObjCMethodDecl *MD = getCurMethodDecl()) { 2165 ObjCInterfaceDecl *IFace = MD->getClassInterface(); 2166 ObjCMethodDecl *Getter; 2167 // FIXME: need to also look locally in the implementation. 2168 if ((Getter = IFace->lookupClassMethod(Sel))) { 2169 // Check the use of this method. 2170 if (DiagnoseUseOfDecl(Getter, MemberLoc)) 2171 return ExprError(); 2172 } 2173 // If we found a getter then this may be a valid dot-reference, we 2174 // will look for the matching setter, in case it is needed. 2175 Selector SetterSel = 2176 SelectorTable::constructSetterName(PP.getIdentifierTable(), 2177 PP.getSelectorTable(), &Member); 2178 ObjCMethodDecl *Setter = IFace->lookupClassMethod(SetterSel); 2179 if (!Setter) { 2180 // If this reference is in an @implementation, also check for 'private' 2181 // methods. 2182 Setter = FindMethodInNestedImplementations(IFace, SetterSel); 2183 } 2184 // Look through local category implementations associated with the class. 2185 if (!Setter) 2186 Setter = IFace->getCategoryClassMethod(SetterSel); 2187 2188 if (Setter && DiagnoseUseOfDecl(Setter, MemberLoc)) 2189 return ExprError(); 2190 2191 if (Getter || Setter) { 2192 QualType PType; 2193 2194 if (Getter) 2195 PType = Getter->getResultType(); 2196 else 2197 // Get the expression type from Setter's incoming parameter. 2198 PType = (*(Setter->param_end() -1))->getType(); 2199 // FIXME: we must check that the setter has property type. 2200 return Owned(new (Context) ObjCImplicitSetterGetterRefExpr(Getter, PType, 2201 Setter, MemberLoc, BaseExpr)); 2202 } 2203 return ExprError(Diag(MemberLoc, diag::err_property_not_found) 2204 << &Member << BaseType); 2205 } 2206 } 2207 // Handle access to Objective-C instance variables, such as "Obj->ivar" and 2208 // (*Obj).ivar. 2209 if ((OpKind == tok::arrow && BaseType->isObjCObjectPointerType()) || 2210 (OpKind == tok::period && BaseType->isObjCInterfaceType())) { 2211 const ObjCObjectPointerType *OPT = BaseType->getAsObjCObjectPointerType(); 2212 const ObjCInterfaceType *IFaceT = 2213 OPT ? OPT->getInterfaceType() : BaseType->getAsObjCInterfaceType(); 2214 if (IFaceT) { 2215 ObjCInterfaceDecl *IDecl = IFaceT->getDecl(); 2216 ObjCInterfaceDecl *ClassDeclared; 2217 ObjCIvarDecl *IV = IDecl->lookupInstanceVariable(&Member, ClassDeclared); 2218 2219 if (IV) { 2220 // If the decl being referenced had an error, return an error for this 2221 // sub-expr without emitting another error, in order to avoid cascading 2222 // error cases. 2223 if (IV->isInvalidDecl()) 2224 return ExprError(); 2225 2226 // Check whether we can reference this field. 2227 if (DiagnoseUseOfDecl(IV, MemberLoc)) 2228 return ExprError(); 2229 if (IV->getAccessControl() != ObjCIvarDecl::Public && 2230 IV->getAccessControl() != ObjCIvarDecl::Package) { 2231 ObjCInterfaceDecl *ClassOfMethodDecl = 0; 2232 if (ObjCMethodDecl *MD = getCurMethodDecl()) 2233 ClassOfMethodDecl = MD->getClassInterface(); 2234 else if (ObjCImpDecl && getCurFunctionDecl()) { 2235 // Case of a c-function declared inside an objc implementation. 2236 // FIXME: For a c-style function nested inside an objc implementation 2237 // class, there is no implementation context available, so we pass 2238 // down the context as argument to this routine. Ideally, this context 2239 // need be passed down in the AST node and somehow calculated from the 2240 // AST for a function decl. 2241 Decl *ImplDecl = ObjCImpDecl.getAs<Decl>(); 2242 if (ObjCImplementationDecl *IMPD = 2243 dyn_cast<ObjCImplementationDecl>(ImplDecl)) 2244 ClassOfMethodDecl = IMPD->getClassInterface(); 2245 else if (ObjCCategoryImplDecl* CatImplClass = 2246 dyn_cast<ObjCCategoryImplDecl>(ImplDecl)) 2247 ClassOfMethodDecl = CatImplClass->getClassInterface(); 2248 } 2249 2250 if (IV->getAccessControl() == ObjCIvarDecl::Private) { 2251 if (ClassDeclared != IDecl || 2252 ClassOfMethodDecl != ClassDeclared) 2253 Diag(MemberLoc, diag::error_private_ivar_access) 2254 << IV->getDeclName(); 2255 } else if (!IDecl->isSuperClassOf(ClassOfMethodDecl)) 2256 // @protected 2257 Diag(MemberLoc, diag::error_protected_ivar_access) 2258 << IV->getDeclName(); 2259 } 2260 2261 return Owned(new (Context) ObjCIvarRefExpr(IV, IV->getType(), 2262 MemberLoc, BaseExpr, 2263 OpKind == tok::arrow)); 2264 } 2265 return ExprError(Diag(MemberLoc, diag::err_typecheck_member_reference_ivar) 2266 << IDecl->getDeclName() << &Member 2267 << BaseExpr->getSourceRange()); 2268 } 2269 } 2270 // Handle properties on 'id' and qualified "id". 2271 if (OpKind == tok::period && (BaseType->isObjCIdType() || 2272 BaseType->isObjCQualifiedIdType())) { 2273 const ObjCObjectPointerType *QIdTy = BaseType->getAsObjCObjectPointerType(); 2274 2275 // Check protocols on qualified interfaces. 2276 Selector Sel = PP.getSelectorTable().getNullarySelector(&Member); 2277 if (Decl *PMDecl = FindGetterNameDecl(QIdTy, Member, Sel, Context)) { 2278 if (ObjCPropertyDecl *PD = dyn_cast<ObjCPropertyDecl>(PMDecl)) { 2279 // Check the use of this declaration 2280 if (DiagnoseUseOfDecl(PD, MemberLoc)) 2281 return ExprError(); 2282 2283 return Owned(new (Context) ObjCPropertyRefExpr(PD, PD->getType(), 2284 MemberLoc, BaseExpr)); 2285 } 2286 if (ObjCMethodDecl *OMD = dyn_cast<ObjCMethodDecl>(PMDecl)) { 2287 // Check the use of this method. 2288 if (DiagnoseUseOfDecl(OMD, MemberLoc)) 2289 return ExprError(); 2290 2291 return Owned(new (Context) ObjCMessageExpr(BaseExpr, Sel, 2292 OMD->getResultType(), 2293 OMD, OpLoc, MemberLoc, 2294 NULL, 0)); 2295 } 2296 } 2297 2298 return ExprError(Diag(MemberLoc, diag::err_property_not_found) 2299 << &Member << BaseType); 2300 } 2301 // Handle Objective-C property access, which is "Obj.property" where Obj is a 2302 // pointer to a (potentially qualified) interface type. 2303 const ObjCObjectPointerType *OPT; 2304 if (OpKind == tok::period && 2305 (OPT = BaseType->getAsObjCInterfacePointerType())) { 2306 const ObjCInterfaceType *IFaceT = OPT->getInterfaceType(); 2307 ObjCInterfaceDecl *IFace = IFaceT->getDecl(); 2308 2309 // Search for a declared property first. 2310 if (ObjCPropertyDecl *PD = IFace->FindPropertyDeclaration(&Member)) { 2311 // Check whether we can reference this property. 2312 if (DiagnoseUseOfDecl(PD, MemberLoc)) 2313 return ExprError(); 2314 QualType ResTy = PD->getType(); 2315 Selector Sel = PP.getSelectorTable().getNullarySelector(&Member); 2316 ObjCMethodDecl *Getter = IFace->lookupInstanceMethod(Sel); 2317 if (DiagnosePropertyAccessorMismatch(PD, Getter, MemberLoc)) 2318 ResTy = Getter->getResultType(); 2319 return Owned(new (Context) ObjCPropertyRefExpr(PD, ResTy, 2320 MemberLoc, BaseExpr)); 2321 } 2322 // Check protocols on qualified interfaces. 2323 for (ObjCObjectPointerType::qual_iterator I = OPT->qual_begin(), 2324 E = OPT->qual_end(); I != E; ++I) 2325 if (ObjCPropertyDecl *PD = (*I)->FindPropertyDeclaration(&Member)) { 2326 // Check whether we can reference this property. 2327 if (DiagnoseUseOfDecl(PD, MemberLoc)) 2328 return ExprError(); 2329 2330 return Owned(new (Context) ObjCPropertyRefExpr(PD, PD->getType(), 2331 MemberLoc, BaseExpr)); 2332 } 2333 for (ObjCObjectPointerType::qual_iterator I = OPT->qual_begin(), 2334 E = OPT->qual_end(); I != E; ++I) 2335 if (ObjCPropertyDecl *PD = (*I)->FindPropertyDeclaration(&Member)) { 2336 // Check whether we can reference this property. 2337 if (DiagnoseUseOfDecl(PD, MemberLoc)) 2338 return ExprError(); 2339 2340 return Owned(new (Context) ObjCPropertyRefExpr(PD, PD->getType(), 2341 MemberLoc, BaseExpr)); 2342 } 2343 // If that failed, look for an "implicit" property by seeing if the nullary 2344 // selector is implemented. 2345 2346 // FIXME: The logic for looking up nullary and unary selectors should be 2347 // shared with the code in ActOnInstanceMessage. 2348 2349 Selector Sel = PP.getSelectorTable().getNullarySelector(&Member); 2350 ObjCMethodDecl *Getter = IFace->lookupInstanceMethod(Sel); 2351 2352 // If this reference is in an @implementation, check for 'private' methods. 2353 if (!Getter) 2354 Getter = FindMethodInNestedImplementations(IFace, Sel); 2355 2356 // Look through local category implementations associated with the class. 2357 if (!Getter) 2358 Getter = IFace->getCategoryInstanceMethod(Sel); 2359 if (Getter) { 2360 // Check if we can reference this property. 2361 if (DiagnoseUseOfDecl(Getter, MemberLoc)) 2362 return ExprError(); 2363 } 2364 // If we found a getter then this may be a valid dot-reference, we 2365 // will look for the matching setter, in case it is needed. 2366 Selector SetterSel = 2367 SelectorTable::constructSetterName(PP.getIdentifierTable(), 2368 PP.getSelectorTable(), &Member); 2369 ObjCMethodDecl *Setter = IFace->lookupInstanceMethod(SetterSel); 2370 if (!Setter) { 2371 // If this reference is in an @implementation, also check for 'private' 2372 // methods. 2373 Setter = FindMethodInNestedImplementations(IFace, SetterSel); 2374 } 2375 // Look through local category implementations associated with the class. 2376 if (!Setter) 2377 Setter = IFace->getCategoryInstanceMethod(SetterSel); 2378 2379 if (Setter && DiagnoseUseOfDecl(Setter, MemberLoc)) 2380 return ExprError(); 2381 2382 if (Getter || Setter) { 2383 QualType PType; 2384 2385 if (Getter) 2386 PType = Getter->getResultType(); 2387 else 2388 // Get the expression type from Setter's incoming parameter. 2389 PType = (*(Setter->param_end() -1))->getType(); 2390 // FIXME: we must check that the setter has property type. 2391 return Owned(new (Context) ObjCImplicitSetterGetterRefExpr(Getter, PType, 2392 Setter, MemberLoc, BaseExpr)); 2393 } 2394 return ExprError(Diag(MemberLoc, diag::err_property_not_found) 2395 << &Member << BaseType); 2396 } 2397 2398 // Handle the following exceptional case (*Obj).isa. 2399 if (OpKind == tok::period && 2400 BaseType->isSpecificBuiltinType(BuiltinType::ObjCId) && 2401 Member.isStr("isa")) 2402 return Owned(new (Context) ObjCIsaExpr(BaseExpr, false, MemberLoc, 2403 Context.getObjCIdType())); 2404 2405 // Handle 'field access' to vectors, such as 'V.xx'. 2406 if (BaseType->isExtVectorType()) { 2407 QualType ret = CheckExtVectorComponent(BaseType, OpLoc, Member, MemberLoc); 2408 if (ret.isNull()) 2409 return ExprError(); 2410 return Owned(new (Context) ExtVectorElementExpr(ret, BaseExpr, Member, 2411 MemberLoc)); 2412 } 2413 2414 Diag(MemberLoc, diag::err_typecheck_member_reference_struct_union) 2415 << BaseType << BaseExpr->getSourceRange(); 2416 2417 // If the user is trying to apply -> or . to a function or function 2418 // pointer, it's probably because they forgot parentheses to call 2419 // the function. Suggest the addition of those parentheses. 2420 if (BaseType == Context.OverloadTy || 2421 BaseType->isFunctionType() || 2422 (BaseType->isPointerType() && 2423 BaseType->getAs<PointerType>()->isFunctionType())) { 2424 SourceLocation Loc = PP.getLocForEndOfToken(BaseExpr->getLocEnd()); 2425 Diag(Loc, diag::note_member_reference_needs_call) 2426 << CodeModificationHint::CreateInsertion(Loc, "()"); 2427 } 2428 2429 return ExprError(); 2430} 2431 2432/// ConvertArgumentsForCall - Converts the arguments specified in 2433/// Args/NumArgs to the parameter types of the function FDecl with 2434/// function prototype Proto. Call is the call expression itself, and 2435/// Fn is the function expression. For a C++ member function, this 2436/// routine does not attempt to convert the object argument. Returns 2437/// true if the call is ill-formed. 2438bool 2439Sema::ConvertArgumentsForCall(CallExpr *Call, Expr *Fn, 2440 FunctionDecl *FDecl, 2441 const FunctionProtoType *Proto, 2442 Expr **Args, unsigned NumArgs, 2443 SourceLocation RParenLoc) { 2444 // C99 6.5.2.2p7 - the arguments are implicitly converted, as if by 2445 // assignment, to the types of the corresponding parameter, ... 2446 unsigned NumArgsInProto = Proto->getNumArgs(); 2447 unsigned NumArgsToCheck = NumArgs; 2448 bool Invalid = false; 2449 2450 // If too few arguments are available (and we don't have default 2451 // arguments for the remaining parameters), don't make the call. 2452 if (NumArgs < NumArgsInProto) { 2453 if (!FDecl || NumArgs < FDecl->getMinRequiredArguments()) 2454 return Diag(RParenLoc, diag::err_typecheck_call_too_few_args) 2455 << Fn->getType()->isBlockPointerType() << Fn->getSourceRange(); 2456 // Use default arguments for missing arguments 2457 NumArgsToCheck = NumArgsInProto; 2458 Call->setNumArgs(Context, NumArgsInProto); 2459 } 2460 2461 // If too many are passed and not variadic, error on the extras and drop 2462 // them. 2463 if (NumArgs > NumArgsInProto) { 2464 if (!Proto->isVariadic()) { 2465 Diag(Args[NumArgsInProto]->getLocStart(), 2466 diag::err_typecheck_call_too_many_args) 2467 << Fn->getType()->isBlockPointerType() << Fn->getSourceRange() 2468 << SourceRange(Args[NumArgsInProto]->getLocStart(), 2469 Args[NumArgs-1]->getLocEnd()); 2470 // This deletes the extra arguments. 2471 Call->setNumArgs(Context, NumArgsInProto); 2472 Invalid = true; 2473 } 2474 NumArgsToCheck = NumArgsInProto; 2475 } 2476 2477 // Continue to check argument types (even if we have too few/many args). 2478 for (unsigned i = 0; i != NumArgsToCheck; i++) { 2479 QualType ProtoArgType = Proto->getArgType(i); 2480 2481 Expr *Arg; 2482 if (i < NumArgs) { 2483 Arg = Args[i]; 2484 2485 if (RequireCompleteType(Arg->getSourceRange().getBegin(), 2486 ProtoArgType, 2487 diag::err_call_incomplete_argument, 2488 Arg->getSourceRange())) 2489 return true; 2490 2491 // Pass the argument. 2492 if (PerformCopyInitialization(Arg, ProtoArgType, "passing")) 2493 return true; 2494 } else { 2495 if (FDecl->getParamDecl(i)->hasUnparsedDefaultArg()) { 2496 Diag (Call->getSourceRange().getBegin(), 2497 diag::err_use_of_default_argument_to_function_declared_later) << 2498 FDecl << cast<CXXRecordDecl>(FDecl->getDeclContext())->getDeclName(); 2499 Diag(UnparsedDefaultArgLocs[FDecl->getParamDecl(i)], 2500 diag::note_default_argument_declared_here); 2501 } else { 2502 Expr *DefaultExpr = FDecl->getParamDecl(i)->getDefaultArg(); 2503 2504 // If the default expression creates temporaries, we need to 2505 // push them to the current stack of expression temporaries so they'll 2506 // be properly destroyed. 2507 if (CXXExprWithTemporaries *E 2508 = dyn_cast_or_null<CXXExprWithTemporaries>(DefaultExpr)) { 2509 assert(!E->shouldDestroyTemporaries() && 2510 "Can't destroy temporaries in a default argument expr!"); 2511 for (unsigned I = 0, N = E->getNumTemporaries(); I != N; ++I) 2512 ExprTemporaries.push_back(E->getTemporary(I)); 2513 } 2514 } 2515 2516 // We already type-checked the argument, so we know it works. 2517 Arg = CXXDefaultArgExpr::Create(Context, FDecl->getParamDecl(i)); 2518 } 2519 2520 QualType ArgType = Arg->getType(); 2521 2522 Call->setArg(i, Arg); 2523 } 2524 2525 // If this is a variadic call, handle args passed through "...". 2526 if (Proto->isVariadic()) { 2527 VariadicCallType CallType = VariadicFunction; 2528 if (Fn->getType()->isBlockPointerType()) 2529 CallType = VariadicBlock; // Block 2530 else if (isa<MemberExpr>(Fn)) 2531 CallType = VariadicMethod; 2532 2533 // Promote the arguments (C99 6.5.2.2p7). 2534 for (unsigned i = NumArgsInProto; i != NumArgs; i++) { 2535 Expr *Arg = Args[i]; 2536 Invalid |= DefaultVariadicArgumentPromotion(Arg, CallType); 2537 Call->setArg(i, Arg); 2538 } 2539 } 2540 2541 return Invalid; 2542} 2543 2544/// ActOnCallExpr - Handle a call to Fn with the specified array of arguments. 2545/// This provides the location of the left/right parens and a list of comma 2546/// locations. 2547Action::OwningExprResult 2548Sema::ActOnCallExpr(Scope *S, ExprArg fn, SourceLocation LParenLoc, 2549 MultiExprArg args, 2550 SourceLocation *CommaLocs, SourceLocation RParenLoc) { 2551 unsigned NumArgs = args.size(); 2552 2553 // Since this might be a postfix expression, get rid of ParenListExprs. 2554 fn = MaybeConvertParenListExprToParenExpr(S, move(fn)); 2555 2556 Expr *Fn = fn.takeAs<Expr>(); 2557 Expr **Args = reinterpret_cast<Expr**>(args.release()); 2558 assert(Fn && "no function call expression"); 2559 FunctionDecl *FDecl = NULL; 2560 NamedDecl *NDecl = NULL; 2561 DeclarationName UnqualifiedName; 2562 2563 if (getLangOptions().CPlusPlus) { 2564 // Determine whether this is a dependent call inside a C++ template, 2565 // in which case we won't do any semantic analysis now. 2566 // FIXME: Will need to cache the results of name lookup (including ADL) in 2567 // Fn. 2568 bool Dependent = false; 2569 if (Fn->isTypeDependent()) 2570 Dependent = true; 2571 else if (Expr::hasAnyTypeDependentArguments(Args, NumArgs)) 2572 Dependent = true; 2573 2574 if (Dependent) 2575 return Owned(new (Context) CallExpr(Context, Fn, Args, NumArgs, 2576 Context.DependentTy, RParenLoc)); 2577 2578 // Determine whether this is a call to an object (C++ [over.call.object]). 2579 if (Fn->getType()->isRecordType()) 2580 return Owned(BuildCallToObjectOfClassType(S, Fn, LParenLoc, Args, NumArgs, 2581 CommaLocs, RParenLoc)); 2582 2583 // Determine whether this is a call to a member function. 2584 if (MemberExpr *MemExpr = dyn_cast<MemberExpr>(Fn->IgnoreParens())) { 2585 NamedDecl *MemDecl = MemExpr->getMemberDecl(); 2586 if (isa<OverloadedFunctionDecl>(MemDecl) || 2587 isa<CXXMethodDecl>(MemDecl) || 2588 (isa<FunctionTemplateDecl>(MemDecl) && 2589 isa<CXXMethodDecl>( 2590 cast<FunctionTemplateDecl>(MemDecl)->getTemplatedDecl()))) 2591 return Owned(BuildCallToMemberFunction(S, Fn, LParenLoc, Args, NumArgs, 2592 CommaLocs, RParenLoc)); 2593 } 2594 } 2595 2596 // If we're directly calling a function, get the appropriate declaration. 2597 // Also, in C++, keep track of whether we should perform argument-dependent 2598 // lookup and whether there were any explicitly-specified template arguments. 2599 Expr *FnExpr = Fn; 2600 bool ADL = true; 2601 bool HasExplicitTemplateArgs = 0; 2602 const TemplateArgument *ExplicitTemplateArgs = 0; 2603 unsigned NumExplicitTemplateArgs = 0; 2604 while (true) { 2605 if (ImplicitCastExpr *IcExpr = dyn_cast<ImplicitCastExpr>(FnExpr)) 2606 FnExpr = IcExpr->getSubExpr(); 2607 else if (ParenExpr *PExpr = dyn_cast<ParenExpr>(FnExpr)) { 2608 // Parentheses around a function disable ADL 2609 // (C++0x [basic.lookup.argdep]p1). 2610 ADL = false; 2611 FnExpr = PExpr->getSubExpr(); 2612 } else if (isa<UnaryOperator>(FnExpr) && 2613 cast<UnaryOperator>(FnExpr)->getOpcode() 2614 == UnaryOperator::AddrOf) { 2615 FnExpr = cast<UnaryOperator>(FnExpr)->getSubExpr(); 2616 } else if (DeclRefExpr *DRExpr = dyn_cast<DeclRefExpr>(FnExpr)) { 2617 // Qualified names disable ADL (C++0x [basic.lookup.argdep]p1). 2618 ADL &= !isa<QualifiedDeclRefExpr>(DRExpr); 2619 NDecl = dyn_cast<NamedDecl>(DRExpr->getDecl()); 2620 break; 2621 } else if (UnresolvedFunctionNameExpr *DepName 2622 = dyn_cast<UnresolvedFunctionNameExpr>(FnExpr)) { 2623 UnqualifiedName = DepName->getName(); 2624 break; 2625 } else if (TemplateIdRefExpr *TemplateIdRef 2626 = dyn_cast<TemplateIdRefExpr>(FnExpr)) { 2627 NDecl = TemplateIdRef->getTemplateName().getAsTemplateDecl(); 2628 if (!NDecl) 2629 NDecl = TemplateIdRef->getTemplateName().getAsOverloadedFunctionDecl(); 2630 HasExplicitTemplateArgs = true; 2631 ExplicitTemplateArgs = TemplateIdRef->getTemplateArgs(); 2632 NumExplicitTemplateArgs = TemplateIdRef->getNumTemplateArgs(); 2633 2634 // C++ [temp.arg.explicit]p6: 2635 // [Note: For simple function names, argument dependent lookup (3.4.2) 2636 // applies even when the function name is not visible within the 2637 // scope of the call. This is because the call still has the syntactic 2638 // form of a function call (3.4.1). But when a function template with 2639 // explicit template arguments is used, the call does not have the 2640 // correct syntactic form unless there is a function template with 2641 // that name visible at the point of the call. If no such name is 2642 // visible, the call is not syntactically well-formed and 2643 // argument-dependent lookup does not apply. If some such name is 2644 // visible, argument dependent lookup applies and additional function 2645 // templates may be found in other namespaces. 2646 // 2647 // The summary of this paragraph is that, if we get to this point and the 2648 // template-id was not a qualified name, then argument-dependent lookup 2649 // is still possible. 2650 if (TemplateIdRef->getQualifier()) 2651 ADL = false; 2652 break; 2653 } else { 2654 // Any kind of name that does not refer to a declaration (or 2655 // set of declarations) disables ADL (C++0x [basic.lookup.argdep]p3). 2656 ADL = false; 2657 break; 2658 } 2659 } 2660 2661 OverloadedFunctionDecl *Ovl = 0; 2662 FunctionTemplateDecl *FunctionTemplate = 0; 2663 if (NDecl) { 2664 FDecl = dyn_cast<FunctionDecl>(NDecl); 2665 if ((FunctionTemplate = dyn_cast<FunctionTemplateDecl>(NDecl))) 2666 FDecl = FunctionTemplate->getTemplatedDecl(); 2667 else 2668 FDecl = dyn_cast<FunctionDecl>(NDecl); 2669 Ovl = dyn_cast<OverloadedFunctionDecl>(NDecl); 2670 } 2671 2672 if (Ovl || FunctionTemplate || 2673 (getLangOptions().CPlusPlus && (FDecl || UnqualifiedName))) { 2674 // We don't perform ADL for implicit declarations of builtins. 2675 if (FDecl && FDecl->getBuiltinID(Context) && FDecl->isImplicit()) 2676 ADL = false; 2677 2678 // We don't perform ADL in C. 2679 if (!getLangOptions().CPlusPlus) 2680 ADL = false; 2681 2682 if (Ovl || FunctionTemplate || ADL) { 2683 FDecl = ResolveOverloadedCallFn(Fn, NDecl, UnqualifiedName, 2684 HasExplicitTemplateArgs, 2685 ExplicitTemplateArgs, 2686 NumExplicitTemplateArgs, 2687 LParenLoc, Args, NumArgs, CommaLocs, 2688 RParenLoc, ADL); 2689 if (!FDecl) 2690 return ExprError(); 2691 2692 // Update Fn to refer to the actual function selected. 2693 Expr *NewFn = 0; 2694 if (QualifiedDeclRefExpr *QDRExpr 2695 = dyn_cast<QualifiedDeclRefExpr>(FnExpr)) 2696 NewFn = new (Context) QualifiedDeclRefExpr(FDecl, FDecl->getType(), 2697 QDRExpr->getLocation(), 2698 false, false, 2699 QDRExpr->getQualifierRange(), 2700 QDRExpr->getQualifier()); 2701 else 2702 NewFn = new (Context) DeclRefExpr(FDecl, FDecl->getType(), 2703 Fn->getSourceRange().getBegin()); 2704 Fn->Destroy(Context); 2705 Fn = NewFn; 2706 } 2707 } 2708 2709 // Promote the function operand. 2710 UsualUnaryConversions(Fn); 2711 2712 // Make the call expr early, before semantic checks. This guarantees cleanup 2713 // of arguments and function on error. 2714 ExprOwningPtr<CallExpr> TheCall(this, new (Context) CallExpr(Context, Fn, 2715 Args, NumArgs, 2716 Context.BoolTy, 2717 RParenLoc)); 2718 2719 const FunctionType *FuncT; 2720 if (!Fn->getType()->isBlockPointerType()) { 2721 // C99 6.5.2.2p1 - "The expression that denotes the called function shall 2722 // have type pointer to function". 2723 const PointerType *PT = Fn->getType()->getAs<PointerType>(); 2724 if (PT == 0) 2725 return ExprError(Diag(LParenLoc, diag::err_typecheck_call_not_function) 2726 << Fn->getType() << Fn->getSourceRange()); 2727 FuncT = PT->getPointeeType()->getAsFunctionType(); 2728 } else { // This is a block call. 2729 FuncT = Fn->getType()->getAs<BlockPointerType>()->getPointeeType()-> 2730 getAsFunctionType(); 2731 } 2732 if (FuncT == 0) 2733 return ExprError(Diag(LParenLoc, diag::err_typecheck_call_not_function) 2734 << Fn->getType() << Fn->getSourceRange()); 2735 2736 // Check for a valid return type 2737 if (!FuncT->getResultType()->isVoidType() && 2738 RequireCompleteType(Fn->getSourceRange().getBegin(), 2739 FuncT->getResultType(), 2740 diag::err_call_incomplete_return, 2741 TheCall->getSourceRange())) 2742 return ExprError(); 2743 2744 // We know the result type of the call, set it. 2745 TheCall->setType(FuncT->getResultType().getNonReferenceType()); 2746 2747 if (const FunctionProtoType *Proto = dyn_cast<FunctionProtoType>(FuncT)) { 2748 if (ConvertArgumentsForCall(&*TheCall, Fn, FDecl, Proto, Args, NumArgs, 2749 RParenLoc)) 2750 return ExprError(); 2751 } else { 2752 assert(isa<FunctionNoProtoType>(FuncT) && "Unknown FunctionType!"); 2753 2754 if (FDecl) { 2755 // Check if we have too few/too many template arguments, based 2756 // on our knowledge of the function definition. 2757 const FunctionDecl *Def = 0; 2758 if (FDecl->getBody(Def) && NumArgs != Def->param_size()) { 2759 const FunctionProtoType *Proto = 2760 Def->getType()->getAsFunctionProtoType(); 2761 if (!Proto || !(Proto->isVariadic() && NumArgs >= Def->param_size())) { 2762 Diag(RParenLoc, diag::warn_call_wrong_number_of_arguments) 2763 << (NumArgs > Def->param_size()) << FDecl << Fn->getSourceRange(); 2764 } 2765 } 2766 } 2767 2768 // Promote the arguments (C99 6.5.2.2p6). 2769 for (unsigned i = 0; i != NumArgs; i++) { 2770 Expr *Arg = Args[i]; 2771 DefaultArgumentPromotion(Arg); 2772 if (RequireCompleteType(Arg->getSourceRange().getBegin(), 2773 Arg->getType(), 2774 diag::err_call_incomplete_argument, 2775 Arg->getSourceRange())) 2776 return ExprError(); 2777 TheCall->setArg(i, Arg); 2778 } 2779 } 2780 2781 if (CXXMethodDecl *Method = dyn_cast_or_null<CXXMethodDecl>(FDecl)) 2782 if (!Method->isStatic()) 2783 return ExprError(Diag(LParenLoc, diag::err_member_call_without_object) 2784 << Fn->getSourceRange()); 2785 2786 // Check for sentinels 2787 if (NDecl) 2788 DiagnoseSentinelCalls(NDecl, LParenLoc, Args, NumArgs); 2789 2790 // Do special checking on direct calls to functions. 2791 if (FDecl) { 2792 if (CheckFunctionCall(FDecl, TheCall.get())) 2793 return ExprError(); 2794 2795 if (unsigned BuiltinID = FDecl->getBuiltinID(Context)) 2796 return CheckBuiltinFunctionCall(BuiltinID, TheCall.take()); 2797 } else if (NDecl) { 2798 if (CheckBlockCall(NDecl, TheCall.get())) 2799 return ExprError(); 2800 } 2801 2802 return MaybeBindToTemporary(TheCall.take()); 2803} 2804 2805Action::OwningExprResult 2806Sema::ActOnCompoundLiteral(SourceLocation LParenLoc, TypeTy *Ty, 2807 SourceLocation RParenLoc, ExprArg InitExpr) { 2808 assert((Ty != 0) && "ActOnCompoundLiteral(): missing type"); 2809 //FIXME: Preserve type source info. 2810 QualType literalType = GetTypeFromParser(Ty); 2811 // FIXME: put back this assert when initializers are worked out. 2812 //assert((InitExpr != 0) && "ActOnCompoundLiteral(): missing expression"); 2813 Expr *literalExpr = static_cast<Expr*>(InitExpr.get()); 2814 2815 if (literalType->isArrayType()) { 2816 if (literalType->isVariableArrayType()) 2817 return ExprError(Diag(LParenLoc, diag::err_variable_object_no_init) 2818 << SourceRange(LParenLoc, literalExpr->getSourceRange().getEnd())); 2819 } else if (!literalType->isDependentType() && 2820 RequireCompleteType(LParenLoc, literalType, 2821 diag::err_typecheck_decl_incomplete_type, 2822 SourceRange(LParenLoc, literalExpr->getSourceRange().getEnd()))) 2823 return ExprError(); 2824 2825 if (CheckInitializerTypes(literalExpr, literalType, LParenLoc, 2826 DeclarationName(), /*FIXME:DirectInit=*/false)) 2827 return ExprError(); 2828 2829 bool isFileScope = getCurFunctionOrMethodDecl() == 0; 2830 if (isFileScope) { // 6.5.2.5p3 2831 if (CheckForConstantInitializer(literalExpr, literalType)) 2832 return ExprError(); 2833 } 2834 InitExpr.release(); 2835 return Owned(new (Context) CompoundLiteralExpr(LParenLoc, literalType, 2836 literalExpr, isFileScope)); 2837} 2838 2839Action::OwningExprResult 2840Sema::ActOnInitList(SourceLocation LBraceLoc, MultiExprArg initlist, 2841 SourceLocation RBraceLoc) { 2842 unsigned NumInit = initlist.size(); 2843 Expr **InitList = reinterpret_cast<Expr**>(initlist.release()); 2844 2845 // Semantic analysis for initializers is done by ActOnDeclarator() and 2846 // CheckInitializer() - it requires knowledge of the object being intialized. 2847 2848 InitListExpr *E = new (Context) InitListExpr(LBraceLoc, InitList, NumInit, 2849 RBraceLoc); 2850 E->setType(Context.VoidTy); // FIXME: just a place holder for now. 2851 return Owned(E); 2852} 2853 2854/// CheckCastTypes - Check type constraints for casting between types. 2855bool Sema::CheckCastTypes(SourceRange TyR, QualType castType, Expr *&castExpr, 2856 CastExpr::CastKind& Kind, bool FunctionalStyle) { 2857 if (getLangOptions().CPlusPlus) 2858 return CXXCheckCStyleCast(TyR, castType, castExpr, Kind, FunctionalStyle); 2859 2860 DefaultFunctionArrayConversion(castExpr); 2861 2862 // C99 6.5.4p2: the cast type needs to be void or scalar and the expression 2863 // type needs to be scalar. 2864 if (castType->isVoidType()) { 2865 // Cast to void allows any expr type. 2866 } else if (!castType->isScalarType() && !castType->isVectorType()) { 2867 if (Context.getCanonicalType(castType).getUnqualifiedType() == 2868 Context.getCanonicalType(castExpr->getType().getUnqualifiedType()) && 2869 (castType->isStructureType() || castType->isUnionType())) { 2870 // GCC struct/union extension: allow cast to self. 2871 // FIXME: Check that the cast destination type is complete. 2872 Diag(TyR.getBegin(), diag::ext_typecheck_cast_nonscalar) 2873 << castType << castExpr->getSourceRange(); 2874 Kind = CastExpr::CK_NoOp; 2875 } else if (castType->isUnionType()) { 2876 // GCC cast to union extension 2877 RecordDecl *RD = castType->getAs<RecordType>()->getDecl(); 2878 RecordDecl::field_iterator Field, FieldEnd; 2879 for (Field = RD->field_begin(), FieldEnd = RD->field_end(); 2880 Field != FieldEnd; ++Field) { 2881 if (Context.getCanonicalType(Field->getType()).getUnqualifiedType() == 2882 Context.getCanonicalType(castExpr->getType()).getUnqualifiedType()) { 2883 Diag(TyR.getBegin(), diag::ext_typecheck_cast_to_union) 2884 << castExpr->getSourceRange(); 2885 break; 2886 } 2887 } 2888 if (Field == FieldEnd) 2889 return Diag(TyR.getBegin(), diag::err_typecheck_cast_to_union_no_type) 2890 << castExpr->getType() << castExpr->getSourceRange(); 2891 Kind = CastExpr::CK_ToUnion; 2892 } else { 2893 // Reject any other conversions to non-scalar types. 2894 return Diag(TyR.getBegin(), diag::err_typecheck_cond_expect_scalar) 2895 << castType << castExpr->getSourceRange(); 2896 } 2897 } else if (!castExpr->getType()->isScalarType() && 2898 !castExpr->getType()->isVectorType()) { 2899 return Diag(castExpr->getLocStart(), 2900 diag::err_typecheck_expect_scalar_operand) 2901 << castExpr->getType() << castExpr->getSourceRange(); 2902 } else if (castType->isExtVectorType()) { 2903 if (CheckExtVectorCast(TyR, castType, castExpr->getType())) 2904 return true; 2905 } else if (castType->isVectorType()) { 2906 if (CheckVectorCast(TyR, castType, castExpr->getType())) 2907 return true; 2908 } else if (castExpr->getType()->isVectorType()) { 2909 if (CheckVectorCast(TyR, castExpr->getType(), castType)) 2910 return true; 2911 } else if (getLangOptions().ObjC1 && isa<ObjCSuperExpr>(castExpr)) { 2912 return Diag(castExpr->getLocStart(), diag::err_illegal_super_cast) << TyR; 2913 } else if (!castType->isArithmeticType()) { 2914 QualType castExprType = castExpr->getType(); 2915 if (!castExprType->isIntegralType() && castExprType->isArithmeticType()) 2916 return Diag(castExpr->getLocStart(), 2917 diag::err_cast_pointer_from_non_pointer_int) 2918 << castExprType << castExpr->getSourceRange(); 2919 } else if (!castExpr->getType()->isArithmeticType()) { 2920 if (!castType->isIntegralType() && castType->isArithmeticType()) 2921 return Diag(castExpr->getLocStart(), 2922 diag::err_cast_pointer_to_non_pointer_int) 2923 << castType << castExpr->getSourceRange(); 2924 } 2925 if (isa<ObjCSelectorExpr>(castExpr)) 2926 return Diag(castExpr->getLocStart(), diag::err_cast_selector_expr); 2927 return false; 2928} 2929 2930bool Sema::CheckVectorCast(SourceRange R, QualType VectorTy, QualType Ty) { 2931 assert(VectorTy->isVectorType() && "Not a vector type!"); 2932 2933 if (Ty->isVectorType() || Ty->isIntegerType()) { 2934 if (Context.getTypeSize(VectorTy) != Context.getTypeSize(Ty)) 2935 return Diag(R.getBegin(), 2936 Ty->isVectorType() ? 2937 diag::err_invalid_conversion_between_vectors : 2938 diag::err_invalid_conversion_between_vector_and_integer) 2939 << VectorTy << Ty << R; 2940 } else 2941 return Diag(R.getBegin(), 2942 diag::err_invalid_conversion_between_vector_and_scalar) 2943 << VectorTy << Ty << R; 2944 2945 return false; 2946} 2947 2948bool Sema::CheckExtVectorCast(SourceRange R, QualType DestTy, QualType SrcTy) { 2949 assert(DestTy->isExtVectorType() && "Not an extended vector type!"); 2950 2951 // If SrcTy is a VectorType, the total size must match to explicitly cast to 2952 // an ExtVectorType. 2953 if (SrcTy->isVectorType()) { 2954 if (Context.getTypeSize(DestTy) != Context.getTypeSize(SrcTy)) 2955 return Diag(R.getBegin(),diag::err_invalid_conversion_between_ext_vectors) 2956 << DestTy << SrcTy << R; 2957 return false; 2958 } 2959 2960 // All non-pointer scalars can be cast to ExtVector type. The appropriate 2961 // conversion will take place first from scalar to elt type, and then 2962 // splat from elt type to vector. 2963 if (SrcTy->isPointerType()) 2964 return Diag(R.getBegin(), 2965 diag::err_invalid_conversion_between_vector_and_scalar) 2966 << DestTy << SrcTy << R; 2967 return false; 2968} 2969 2970Action::OwningExprResult 2971Sema::ActOnCastExpr(Scope *S, SourceLocation LParenLoc, TypeTy *Ty, 2972 SourceLocation RParenLoc, ExprArg Op) { 2973 CastExpr::CastKind Kind = CastExpr::CK_Unknown; 2974 2975 assert((Ty != 0) && (Op.get() != 0) && 2976 "ActOnCastExpr(): missing type or expr"); 2977 2978 Expr *castExpr = (Expr *)Op.get(); 2979 //FIXME: Preserve type source info. 2980 QualType castType = GetTypeFromParser(Ty); 2981 2982 // If the Expr being casted is a ParenListExpr, handle it specially. 2983 if (isa<ParenListExpr>(castExpr)) 2984 return ActOnCastOfParenListExpr(S, LParenLoc, RParenLoc, move(Op),castType); 2985 2986 if (CheckCastTypes(SourceRange(LParenLoc, RParenLoc), castType, castExpr, 2987 Kind)) 2988 return ExprError(); 2989 2990 Op.release(); 2991 return Owned(new (Context) CStyleCastExpr(castType.getNonReferenceType(), 2992 Kind, castExpr, castType, 2993 LParenLoc, RParenLoc)); 2994} 2995 2996/// This is not an AltiVec-style cast, so turn the ParenListExpr into a sequence 2997/// of comma binary operators. 2998Action::OwningExprResult 2999Sema::MaybeConvertParenListExprToParenExpr(Scope *S, ExprArg EA) { 3000 Expr *expr = EA.takeAs<Expr>(); 3001 ParenListExpr *E = dyn_cast<ParenListExpr>(expr); 3002 if (!E) 3003 return Owned(expr); 3004 3005 OwningExprResult Result(*this, E->getExpr(0)); 3006 3007 for (unsigned i = 1, e = E->getNumExprs(); i != e && !Result.isInvalid(); ++i) 3008 Result = ActOnBinOp(S, E->getExprLoc(), tok::comma, move(Result), 3009 Owned(E->getExpr(i))); 3010 3011 return ActOnParenExpr(E->getLParenLoc(), E->getRParenLoc(), move(Result)); 3012} 3013 3014Action::OwningExprResult 3015Sema::ActOnCastOfParenListExpr(Scope *S, SourceLocation LParenLoc, 3016 SourceLocation RParenLoc, ExprArg Op, 3017 QualType Ty) { 3018 ParenListExpr *PE = (ParenListExpr *)Op.get(); 3019 3020 // If this is an altivec initializer, '(' type ')' '(' init, ..., init ')' 3021 // then handle it as such. 3022 if (getLangOptions().AltiVec && Ty->isVectorType()) { 3023 if (PE->getNumExprs() == 0) { 3024 Diag(PE->getExprLoc(), diag::err_altivec_empty_initializer); 3025 return ExprError(); 3026 } 3027 3028 llvm::SmallVector<Expr *, 8> initExprs; 3029 for (unsigned i = 0, e = PE->getNumExprs(); i != e; ++i) 3030 initExprs.push_back(PE->getExpr(i)); 3031 3032 // FIXME: This means that pretty-printing the final AST will produce curly 3033 // braces instead of the original commas. 3034 Op.release(); 3035 InitListExpr *E = new (Context) InitListExpr(LParenLoc, &initExprs[0], 3036 initExprs.size(), RParenLoc); 3037 E->setType(Ty); 3038 return ActOnCompoundLiteral(LParenLoc, Ty.getAsOpaquePtr(), RParenLoc, 3039 Owned(E)); 3040 } else { 3041 // This is not an AltiVec-style cast, so turn the ParenListExpr into a 3042 // sequence of BinOp comma operators. 3043 Op = MaybeConvertParenListExprToParenExpr(S, move(Op)); 3044 return ActOnCastExpr(S, LParenLoc, Ty.getAsOpaquePtr(), RParenLoc,move(Op)); 3045 } 3046} 3047 3048Action::OwningExprResult Sema::ActOnParenListExpr(SourceLocation L, 3049 SourceLocation R, 3050 MultiExprArg Val) { 3051 unsigned nexprs = Val.size(); 3052 Expr **exprs = reinterpret_cast<Expr**>(Val.release()); 3053 assert((exprs != 0) && "ActOnParenListExpr() missing expr list"); 3054 Expr *expr = new (Context) ParenListExpr(Context, L, exprs, nexprs, R); 3055 return Owned(expr); 3056} 3057 3058/// Note that lhs is not null here, even if this is the gnu "x ?: y" extension. 3059/// In that case, lhs = cond. 3060/// C99 6.5.15 3061QualType Sema::CheckConditionalOperands(Expr *&Cond, Expr *&LHS, Expr *&RHS, 3062 SourceLocation QuestionLoc) { 3063 // C++ is sufficiently different to merit its own checker. 3064 if (getLangOptions().CPlusPlus) 3065 return CXXCheckConditionalOperands(Cond, LHS, RHS, QuestionLoc); 3066 3067 UsualUnaryConversions(Cond); 3068 UsualUnaryConversions(LHS); 3069 UsualUnaryConversions(RHS); 3070 QualType CondTy = Cond->getType(); 3071 QualType LHSTy = LHS->getType(); 3072 QualType RHSTy = RHS->getType(); 3073 3074 // first, check the condition. 3075 if (!CondTy->isScalarType()) { // C99 6.5.15p2 3076 Diag(Cond->getLocStart(), diag::err_typecheck_cond_expect_scalar) 3077 << CondTy; 3078 return QualType(); 3079 } 3080 3081 // Now check the two expressions. 3082 if (LHSTy->isVectorType() || RHSTy->isVectorType()) 3083 return CheckVectorOperands(QuestionLoc, LHS, RHS); 3084 3085 // If both operands have arithmetic type, do the usual arithmetic conversions 3086 // to find a common type: C99 6.5.15p3,5. 3087 if (LHSTy->isArithmeticType() && RHSTy->isArithmeticType()) { 3088 UsualArithmeticConversions(LHS, RHS); 3089 return LHS->getType(); 3090 } 3091 3092 // If both operands are the same structure or union type, the result is that 3093 // type. 3094 if (const RecordType *LHSRT = LHSTy->getAs<RecordType>()) { // C99 6.5.15p3 3095 if (const RecordType *RHSRT = RHSTy->getAs<RecordType>()) 3096 if (LHSRT->getDecl() == RHSRT->getDecl()) 3097 // "If both the operands have structure or union type, the result has 3098 // that type." This implies that CV qualifiers are dropped. 3099 return LHSTy.getUnqualifiedType(); 3100 // FIXME: Type of conditional expression must be complete in C mode. 3101 } 3102 3103 // C99 6.5.15p5: "If both operands have void type, the result has void type." 3104 // The following || allows only one side to be void (a GCC-ism). 3105 if (LHSTy->isVoidType() || RHSTy->isVoidType()) { 3106 if (!LHSTy->isVoidType()) 3107 Diag(RHS->getLocStart(), diag::ext_typecheck_cond_one_void) 3108 << RHS->getSourceRange(); 3109 if (!RHSTy->isVoidType()) 3110 Diag(LHS->getLocStart(), diag::ext_typecheck_cond_one_void) 3111 << LHS->getSourceRange(); 3112 ImpCastExprToType(LHS, Context.VoidTy); 3113 ImpCastExprToType(RHS, Context.VoidTy); 3114 return Context.VoidTy; 3115 } 3116 // C99 6.5.15p6 - "if one operand is a null pointer constant, the result has 3117 // the type of the other operand." 3118 if ((LHSTy->isAnyPointerType() || LHSTy->isBlockPointerType()) && 3119 RHS->isNullPointerConstant(Context)) { 3120 ImpCastExprToType(RHS, LHSTy); // promote the null to a pointer. 3121 return LHSTy; 3122 } 3123 if ((RHSTy->isAnyPointerType() || RHSTy->isBlockPointerType()) && 3124 LHS->isNullPointerConstant(Context)) { 3125 ImpCastExprToType(LHS, RHSTy); // promote the null to a pointer. 3126 return RHSTy; 3127 } 3128 // Handle things like Class and struct objc_class*. Here we case the result 3129 // to the pseudo-builtin, because that will be implicitly cast back to the 3130 // redefinition type if an attempt is made to access its fields. 3131 if (LHSTy->isObjCClassType() && 3132 (RHSTy.getDesugaredType() == Context.ObjCClassRedefinitionType)) { 3133 ImpCastExprToType(RHS, LHSTy); 3134 return LHSTy; 3135 } 3136 if (RHSTy->isObjCClassType() && 3137 (LHSTy.getDesugaredType() == Context.ObjCClassRedefinitionType)) { 3138 ImpCastExprToType(LHS, RHSTy); 3139 return RHSTy; 3140 } 3141 // And the same for struct objc_object* / id 3142 if (LHSTy->isObjCIdType() && 3143 (RHSTy.getDesugaredType() == Context.ObjCIdRedefinitionType)) { 3144 ImpCastExprToType(RHS, LHSTy); 3145 return LHSTy; 3146 } 3147 if (RHSTy->isObjCIdType() && 3148 (LHSTy.getDesugaredType() == Context.ObjCIdRedefinitionType)) { 3149 ImpCastExprToType(LHS, RHSTy); 3150 return RHSTy; 3151 } 3152 // Handle block pointer types. 3153 if (LHSTy->isBlockPointerType() || RHSTy->isBlockPointerType()) { 3154 if (!LHSTy->isBlockPointerType() || !RHSTy->isBlockPointerType()) { 3155 if (LHSTy->isVoidPointerType() || RHSTy->isVoidPointerType()) { 3156 QualType destType = Context.getPointerType(Context.VoidTy); 3157 ImpCastExprToType(LHS, destType); 3158 ImpCastExprToType(RHS, destType); 3159 return destType; 3160 } 3161 Diag(QuestionLoc, diag::err_typecheck_cond_incompatible_operands) 3162 << LHSTy << RHSTy << LHS->getSourceRange() << RHS->getSourceRange(); 3163 return QualType(); 3164 } 3165 // We have 2 block pointer types. 3166 if (Context.getCanonicalType(LHSTy) == Context.getCanonicalType(RHSTy)) { 3167 // Two identical block pointer types are always compatible. 3168 return LHSTy; 3169 } 3170 // The block pointer types aren't identical, continue checking. 3171 QualType lhptee = LHSTy->getAs<BlockPointerType>()->getPointeeType(); 3172 QualType rhptee = RHSTy->getAs<BlockPointerType>()->getPointeeType(); 3173 3174 if (!Context.typesAreCompatible(lhptee.getUnqualifiedType(), 3175 rhptee.getUnqualifiedType())) { 3176 Diag(QuestionLoc, diag::warn_typecheck_cond_incompatible_pointers) 3177 << LHSTy << RHSTy << LHS->getSourceRange() << RHS->getSourceRange(); 3178 // In this situation, we assume void* type. No especially good 3179 // reason, but this is what gcc does, and we do have to pick 3180 // to get a consistent AST. 3181 QualType incompatTy = Context.getPointerType(Context.VoidTy); 3182 ImpCastExprToType(LHS, incompatTy); 3183 ImpCastExprToType(RHS, incompatTy); 3184 return incompatTy; 3185 } 3186 // The block pointer types are compatible. 3187 ImpCastExprToType(LHS, LHSTy); 3188 ImpCastExprToType(RHS, LHSTy); 3189 return LHSTy; 3190 } 3191 // Check constraints for Objective-C object pointers types. 3192 if (LHSTy->isObjCObjectPointerType() && RHSTy->isObjCObjectPointerType()) { 3193 3194 if (Context.getCanonicalType(LHSTy) == Context.getCanonicalType(RHSTy)) { 3195 // Two identical object pointer types are always compatible. 3196 return LHSTy; 3197 } 3198 const ObjCObjectPointerType *LHSOPT = LHSTy->getAsObjCObjectPointerType(); 3199 const ObjCObjectPointerType *RHSOPT = RHSTy->getAsObjCObjectPointerType(); 3200 QualType compositeType = LHSTy; 3201 3202 // If both operands are interfaces and either operand can be 3203 // assigned to the other, use that type as the composite 3204 // type. This allows 3205 // xxx ? (A*) a : (B*) b 3206 // where B is a subclass of A. 3207 // 3208 // Additionally, as for assignment, if either type is 'id' 3209 // allow silent coercion. Finally, if the types are 3210 // incompatible then make sure to use 'id' as the composite 3211 // type so the result is acceptable for sending messages to. 3212 3213 // FIXME: Consider unifying with 'areComparableObjCPointerTypes'. 3214 // It could return the composite type. 3215 if (Context.canAssignObjCInterfaces(LHSOPT, RHSOPT)) { 3216 compositeType = LHSTy; 3217 } else if (Context.canAssignObjCInterfaces(RHSOPT, LHSOPT)) { 3218 compositeType = RHSTy; 3219 } else if ((LHSTy->isObjCQualifiedIdType() || 3220 RHSTy->isObjCQualifiedIdType()) && 3221 Context.ObjCQualifiedIdTypesAreCompatible(LHSTy, RHSTy, true)) { 3222 // Need to handle "id<xx>" explicitly. 3223 // GCC allows qualified id and any Objective-C type to devolve to 3224 // id. Currently localizing to here until clear this should be 3225 // part of ObjCQualifiedIdTypesAreCompatible. 3226 compositeType = Context.getObjCIdType(); 3227 } else if (LHSTy->isObjCIdType() || RHSTy->isObjCIdType()) { 3228 compositeType = Context.getObjCIdType(); 3229 } else { 3230 Diag(QuestionLoc, diag::ext_typecheck_cond_incompatible_operands) 3231 << LHSTy << RHSTy 3232 << LHS->getSourceRange() << RHS->getSourceRange(); 3233 QualType incompatTy = Context.getObjCIdType(); 3234 ImpCastExprToType(LHS, incompatTy); 3235 ImpCastExprToType(RHS, incompatTy); 3236 return incompatTy; 3237 } 3238 // The object pointer types are compatible. 3239 ImpCastExprToType(LHS, compositeType); 3240 ImpCastExprToType(RHS, compositeType); 3241 return compositeType; 3242 } 3243 // Check Objective-C object pointer types and 'void *' 3244 if (LHSTy->isVoidPointerType() && RHSTy->isObjCObjectPointerType()) { 3245 QualType lhptee = LHSTy->getAs<PointerType>()->getPointeeType(); 3246 QualType rhptee = RHSTy->getAsObjCObjectPointerType()->getPointeeType(); 3247 QualType destPointee = lhptee.getQualifiedType(rhptee.getCVRQualifiers()); 3248 QualType destType = Context.getPointerType(destPointee); 3249 ImpCastExprToType(LHS, destType); // add qualifiers if necessary 3250 ImpCastExprToType(RHS, destType); // promote to void* 3251 return destType; 3252 } 3253 if (LHSTy->isObjCObjectPointerType() && RHSTy->isVoidPointerType()) { 3254 QualType lhptee = LHSTy->getAsObjCObjectPointerType()->getPointeeType(); 3255 QualType rhptee = RHSTy->getAs<PointerType>()->getPointeeType(); 3256 QualType destPointee = rhptee.getQualifiedType(lhptee.getCVRQualifiers()); 3257 QualType destType = Context.getPointerType(destPointee); 3258 ImpCastExprToType(RHS, destType); // add qualifiers if necessary 3259 ImpCastExprToType(LHS, destType); // promote to void* 3260 return destType; 3261 } 3262 // Check constraints for C object pointers types (C99 6.5.15p3,6). 3263 if (LHSTy->isPointerType() && RHSTy->isPointerType()) { 3264 // get the "pointed to" types 3265 QualType lhptee = LHSTy->getAs<PointerType>()->getPointeeType(); 3266 QualType rhptee = RHSTy->getAs<PointerType>()->getPointeeType(); 3267 3268 // ignore qualifiers on void (C99 6.5.15p3, clause 6) 3269 if (lhptee->isVoidType() && rhptee->isIncompleteOrObjectType()) { 3270 // Figure out necessary qualifiers (C99 6.5.15p6) 3271 QualType destPointee=lhptee.getQualifiedType(rhptee.getCVRQualifiers()); 3272 QualType destType = Context.getPointerType(destPointee); 3273 ImpCastExprToType(LHS, destType); // add qualifiers if necessary 3274 ImpCastExprToType(RHS, destType); // promote to void* 3275 return destType; 3276 } 3277 if (rhptee->isVoidType() && lhptee->isIncompleteOrObjectType()) { 3278 QualType destPointee=rhptee.getQualifiedType(lhptee.getCVRQualifiers()); 3279 QualType destType = Context.getPointerType(destPointee); 3280 ImpCastExprToType(LHS, destType); // add qualifiers if necessary 3281 ImpCastExprToType(RHS, destType); // promote to void* 3282 return destType; 3283 } 3284 3285 if (Context.getCanonicalType(LHSTy) == Context.getCanonicalType(RHSTy)) { 3286 // Two identical pointer types are always compatible. 3287 return LHSTy; 3288 } 3289 if (!Context.typesAreCompatible(lhptee.getUnqualifiedType(), 3290 rhptee.getUnqualifiedType())) { 3291 Diag(QuestionLoc, diag::warn_typecheck_cond_incompatible_pointers) 3292 << LHSTy << RHSTy << LHS->getSourceRange() << RHS->getSourceRange(); 3293 // In this situation, we assume void* type. No especially good 3294 // reason, but this is what gcc does, and we do have to pick 3295 // to get a consistent AST. 3296 QualType incompatTy = Context.getPointerType(Context.VoidTy); 3297 ImpCastExprToType(LHS, incompatTy); 3298 ImpCastExprToType(RHS, incompatTy); 3299 return incompatTy; 3300 } 3301 // The pointer types are compatible. 3302 // C99 6.5.15p6: If both operands are pointers to compatible types *or* to 3303 // differently qualified versions of compatible types, the result type is 3304 // a pointer to an appropriately qualified version of the *composite* 3305 // type. 3306 // FIXME: Need to calculate the composite type. 3307 // FIXME: Need to add qualifiers 3308 ImpCastExprToType(LHS, LHSTy); 3309 ImpCastExprToType(RHS, LHSTy); 3310 return LHSTy; 3311 } 3312 3313 // GCC compatibility: soften pointer/integer mismatch. 3314 if (RHSTy->isPointerType() && LHSTy->isIntegerType()) { 3315 Diag(QuestionLoc, diag::warn_typecheck_cond_pointer_integer_mismatch) 3316 << LHSTy << RHSTy << LHS->getSourceRange() << RHS->getSourceRange(); 3317 ImpCastExprToType(LHS, RHSTy); // promote the integer to a pointer. 3318 return RHSTy; 3319 } 3320 if (LHSTy->isPointerType() && RHSTy->isIntegerType()) { 3321 Diag(QuestionLoc, diag::warn_typecheck_cond_pointer_integer_mismatch) 3322 << LHSTy << RHSTy << LHS->getSourceRange() << RHS->getSourceRange(); 3323 ImpCastExprToType(RHS, LHSTy); // promote the integer to a pointer. 3324 return LHSTy; 3325 } 3326 3327 // Otherwise, the operands are not compatible. 3328 Diag(QuestionLoc, diag::err_typecheck_cond_incompatible_operands) 3329 << LHSTy << RHSTy << LHS->getSourceRange() << RHS->getSourceRange(); 3330 return QualType(); 3331} 3332 3333/// ActOnConditionalOp - Parse a ?: operation. Note that 'LHS' may be null 3334/// in the case of a the GNU conditional expr extension. 3335Action::OwningExprResult Sema::ActOnConditionalOp(SourceLocation QuestionLoc, 3336 SourceLocation ColonLoc, 3337 ExprArg Cond, ExprArg LHS, 3338 ExprArg RHS) { 3339 Expr *CondExpr = (Expr *) Cond.get(); 3340 Expr *LHSExpr = (Expr *) LHS.get(), *RHSExpr = (Expr *) RHS.get(); 3341 3342 // If this is the gnu "x ?: y" extension, analyze the types as though the LHS 3343 // was the condition. 3344 bool isLHSNull = LHSExpr == 0; 3345 if (isLHSNull) 3346 LHSExpr = CondExpr; 3347 3348 QualType result = CheckConditionalOperands(CondExpr, LHSExpr, 3349 RHSExpr, QuestionLoc); 3350 if (result.isNull()) 3351 return ExprError(); 3352 3353 Cond.release(); 3354 LHS.release(); 3355 RHS.release(); 3356 return Owned(new (Context) ConditionalOperator(CondExpr, 3357 isLHSNull ? 0 : LHSExpr, 3358 RHSExpr, result)); 3359} 3360 3361// CheckPointerTypesForAssignment - This is a very tricky routine (despite 3362// being closely modeled after the C99 spec:-). The odd characteristic of this 3363// routine is it effectively iqnores the qualifiers on the top level pointee. 3364// This circumvents the usual type rules specified in 6.2.7p1 & 6.7.5.[1-3]. 3365// FIXME: add a couple examples in this comment. 3366Sema::AssignConvertType 3367Sema::CheckPointerTypesForAssignment(QualType lhsType, QualType rhsType) { 3368 QualType lhptee, rhptee; 3369 3370 if ((lhsType->isObjCClassType() && 3371 (rhsType.getDesugaredType() == Context.ObjCClassRedefinitionType)) || 3372 (rhsType->isObjCClassType() && 3373 (lhsType.getDesugaredType() == Context.ObjCClassRedefinitionType))) { 3374 return Compatible; 3375 } 3376 3377 // get the "pointed to" type (ignoring qualifiers at the top level) 3378 lhptee = lhsType->getAs<PointerType>()->getPointeeType(); 3379 rhptee = rhsType->getAs<PointerType>()->getPointeeType(); 3380 3381 // make sure we operate on the canonical type 3382 lhptee = Context.getCanonicalType(lhptee); 3383 rhptee = Context.getCanonicalType(rhptee); 3384 3385 AssignConvertType ConvTy = Compatible; 3386 3387 // C99 6.5.16.1p1: This following citation is common to constraints 3388 // 3 & 4 (below). ...and the type *pointed to* by the left has all the 3389 // qualifiers of the type *pointed to* by the right; 3390 // FIXME: Handle ExtQualType 3391 if (!lhptee.isAtLeastAsQualifiedAs(rhptee)) 3392 ConvTy = CompatiblePointerDiscardsQualifiers; 3393 3394 // C99 6.5.16.1p1 (constraint 4): If one operand is a pointer to an object or 3395 // incomplete type and the other is a pointer to a qualified or unqualified 3396 // version of void... 3397 if (lhptee->isVoidType()) { 3398 if (rhptee->isIncompleteOrObjectType()) 3399 return ConvTy; 3400 3401 // As an extension, we allow cast to/from void* to function pointer. 3402 assert(rhptee->isFunctionType()); 3403 return FunctionVoidPointer; 3404 } 3405 3406 if (rhptee->isVoidType()) { 3407 if (lhptee->isIncompleteOrObjectType()) 3408 return ConvTy; 3409 3410 // As an extension, we allow cast to/from void* to function pointer. 3411 assert(lhptee->isFunctionType()); 3412 return FunctionVoidPointer; 3413 } 3414 // C99 6.5.16.1p1 (constraint 3): both operands are pointers to qualified or 3415 // unqualified versions of compatible types, ... 3416 lhptee = lhptee.getUnqualifiedType(); 3417 rhptee = rhptee.getUnqualifiedType(); 3418 if (!Context.typesAreCompatible(lhptee, rhptee)) { 3419 // Check if the pointee types are compatible ignoring the sign. 3420 // We explicitly check for char so that we catch "char" vs 3421 // "unsigned char" on systems where "char" is unsigned. 3422 if (lhptee->isCharType()) { 3423 lhptee = Context.UnsignedCharTy; 3424 } else if (lhptee->isSignedIntegerType()) { 3425 lhptee = Context.getCorrespondingUnsignedType(lhptee); 3426 } 3427 if (rhptee->isCharType()) { 3428 rhptee = Context.UnsignedCharTy; 3429 } else if (rhptee->isSignedIntegerType()) { 3430 rhptee = Context.getCorrespondingUnsignedType(rhptee); 3431 } 3432 if (lhptee == rhptee) { 3433 // Types are compatible ignoring the sign. Qualifier incompatibility 3434 // takes priority over sign incompatibility because the sign 3435 // warning can be disabled. 3436 if (ConvTy != Compatible) 3437 return ConvTy; 3438 return IncompatiblePointerSign; 3439 } 3440 // General pointer incompatibility takes priority over qualifiers. 3441 return IncompatiblePointer; 3442 } 3443 return ConvTy; 3444} 3445 3446/// CheckBlockPointerTypesForAssignment - This routine determines whether two 3447/// block pointer types are compatible or whether a block and normal pointer 3448/// are compatible. It is more restrict than comparing two function pointer 3449// types. 3450Sema::AssignConvertType 3451Sema::CheckBlockPointerTypesForAssignment(QualType lhsType, 3452 QualType rhsType) { 3453 QualType lhptee, rhptee; 3454 3455 // get the "pointed to" type (ignoring qualifiers at the top level) 3456 lhptee = lhsType->getAs<BlockPointerType>()->getPointeeType(); 3457 rhptee = rhsType->getAs<BlockPointerType>()->getPointeeType(); 3458 3459 // make sure we operate on the canonical type 3460 lhptee = Context.getCanonicalType(lhptee); 3461 rhptee = Context.getCanonicalType(rhptee); 3462 3463 AssignConvertType ConvTy = Compatible; 3464 3465 // For blocks we enforce that qualifiers are identical. 3466 if (lhptee.getCVRQualifiers() != rhptee.getCVRQualifiers()) 3467 ConvTy = CompatiblePointerDiscardsQualifiers; 3468 3469 if (!Context.typesAreCompatible(lhptee, rhptee)) 3470 return IncompatibleBlockPointer; 3471 return ConvTy; 3472} 3473 3474/// CheckAssignmentConstraints (C99 6.5.16) - This routine currently 3475/// has code to accommodate several GCC extensions when type checking 3476/// pointers. Here are some objectionable examples that GCC considers warnings: 3477/// 3478/// int a, *pint; 3479/// short *pshort; 3480/// struct foo *pfoo; 3481/// 3482/// pint = pshort; // warning: assignment from incompatible pointer type 3483/// a = pint; // warning: assignment makes integer from pointer without a cast 3484/// pint = a; // warning: assignment makes pointer from integer without a cast 3485/// pint = pfoo; // warning: assignment from incompatible pointer type 3486/// 3487/// As a result, the code for dealing with pointers is more complex than the 3488/// C99 spec dictates. 3489/// 3490Sema::AssignConvertType 3491Sema::CheckAssignmentConstraints(QualType lhsType, QualType rhsType) { 3492 // Get canonical types. We're not formatting these types, just comparing 3493 // them. 3494 lhsType = Context.getCanonicalType(lhsType).getUnqualifiedType(); 3495 rhsType = Context.getCanonicalType(rhsType).getUnqualifiedType(); 3496 3497 if (lhsType == rhsType) 3498 return Compatible; // Common case: fast path an exact match. 3499 3500 if ((lhsType->isObjCClassType() && 3501 (rhsType.getDesugaredType() == Context.ObjCClassRedefinitionType)) || 3502 (rhsType->isObjCClassType() && 3503 (lhsType.getDesugaredType() == Context.ObjCClassRedefinitionType))) { 3504 return Compatible; 3505 } 3506 3507 // If the left-hand side is a reference type, then we are in a 3508 // (rare!) case where we've allowed the use of references in C, 3509 // e.g., as a parameter type in a built-in function. In this case, 3510 // just make sure that the type referenced is compatible with the 3511 // right-hand side type. The caller is responsible for adjusting 3512 // lhsType so that the resulting expression does not have reference 3513 // type. 3514 if (const ReferenceType *lhsTypeRef = lhsType->getAs<ReferenceType>()) { 3515 if (Context.typesAreCompatible(lhsTypeRef->getPointeeType(), rhsType)) 3516 return Compatible; 3517 return Incompatible; 3518 } 3519 // Allow scalar to ExtVector assignments, and assignments of an ExtVector type 3520 // to the same ExtVector type. 3521 if (lhsType->isExtVectorType()) { 3522 if (rhsType->isExtVectorType()) 3523 return lhsType == rhsType ? Compatible : Incompatible; 3524 if (!rhsType->isVectorType() && rhsType->isArithmeticType()) 3525 return Compatible; 3526 } 3527 3528 if (lhsType->isVectorType() || rhsType->isVectorType()) { 3529 // If we are allowing lax vector conversions, and LHS and RHS are both 3530 // vectors, the total size only needs to be the same. This is a bitcast; 3531 // no bits are changed but the result type is different. 3532 if (getLangOptions().LaxVectorConversions && 3533 lhsType->isVectorType() && rhsType->isVectorType()) { 3534 if (Context.getTypeSize(lhsType) == Context.getTypeSize(rhsType)) 3535 return IncompatibleVectors; 3536 } 3537 return Incompatible; 3538 } 3539 3540 if (lhsType->isArithmeticType() && rhsType->isArithmeticType()) 3541 return Compatible; 3542 3543 if (isa<PointerType>(lhsType)) { 3544 if (rhsType->isIntegerType()) 3545 return IntToPointer; 3546 3547 if (isa<PointerType>(rhsType)) 3548 return CheckPointerTypesForAssignment(lhsType, rhsType); 3549 3550 // In general, C pointers are not compatible with ObjC object pointers. 3551 if (isa<ObjCObjectPointerType>(rhsType)) { 3552 if (lhsType->isVoidPointerType()) // an exception to the rule. 3553 return Compatible; 3554 return IncompatiblePointer; 3555 } 3556 if (rhsType->getAs<BlockPointerType>()) { 3557 if (lhsType->getAs<PointerType>()->getPointeeType()->isVoidType()) 3558 return Compatible; 3559 3560 // Treat block pointers as objects. 3561 if (getLangOptions().ObjC1 && lhsType->isObjCIdType()) 3562 return Compatible; 3563 } 3564 return Incompatible; 3565 } 3566 3567 if (isa<BlockPointerType>(lhsType)) { 3568 if (rhsType->isIntegerType()) 3569 return IntToBlockPointer; 3570 3571 // Treat block pointers as objects. 3572 if (getLangOptions().ObjC1 && rhsType->isObjCIdType()) 3573 return Compatible; 3574 3575 if (rhsType->isBlockPointerType()) 3576 return CheckBlockPointerTypesForAssignment(lhsType, rhsType); 3577 3578 if (const PointerType *RHSPT = rhsType->getAs<PointerType>()) { 3579 if (RHSPT->getPointeeType()->isVoidType()) 3580 return Compatible; 3581 } 3582 return Incompatible; 3583 } 3584 3585 if (isa<ObjCObjectPointerType>(lhsType)) { 3586 if (rhsType->isIntegerType()) 3587 return IntToPointer; 3588 3589 // In general, C pointers are not compatible with ObjC object pointers. 3590 if (isa<PointerType>(rhsType)) { 3591 if (rhsType->isVoidPointerType()) // an exception to the rule. 3592 return Compatible; 3593 return IncompatiblePointer; 3594 } 3595 if (rhsType->isObjCObjectPointerType()) { 3596 if (lhsType->isObjCBuiltinType() || rhsType->isObjCBuiltinType()) 3597 return Compatible; 3598 if (Context.typesAreCompatible(lhsType, rhsType)) 3599 return Compatible; 3600 if (lhsType->isObjCQualifiedIdType() || rhsType->isObjCQualifiedIdType()) 3601 return IncompatibleObjCQualifiedId; 3602 return IncompatiblePointer; 3603 } 3604 if (const PointerType *RHSPT = rhsType->getAs<PointerType>()) { 3605 if (RHSPT->getPointeeType()->isVoidType()) 3606 return Compatible; 3607 } 3608 // Treat block pointers as objects. 3609 if (rhsType->isBlockPointerType()) 3610 return Compatible; 3611 return Incompatible; 3612 } 3613 if (isa<PointerType>(rhsType)) { 3614 // C99 6.5.16.1p1: the left operand is _Bool and the right is a pointer. 3615 if (lhsType == Context.BoolTy) 3616 return Compatible; 3617 3618 if (lhsType->isIntegerType()) 3619 return PointerToInt; 3620 3621 if (isa<PointerType>(lhsType)) 3622 return CheckPointerTypesForAssignment(lhsType, rhsType); 3623 3624 if (isa<BlockPointerType>(lhsType) && 3625 rhsType->getAs<PointerType>()->getPointeeType()->isVoidType()) 3626 return Compatible; 3627 return Incompatible; 3628 } 3629 if (isa<ObjCObjectPointerType>(rhsType)) { 3630 // C99 6.5.16.1p1: the left operand is _Bool and the right is a pointer. 3631 if (lhsType == Context.BoolTy) 3632 return Compatible; 3633 3634 if (lhsType->isIntegerType()) 3635 return PointerToInt; 3636 3637 // In general, C pointers are not compatible with ObjC object pointers. 3638 if (isa<PointerType>(lhsType)) { 3639 if (lhsType->isVoidPointerType()) // an exception to the rule. 3640 return Compatible; 3641 return IncompatiblePointer; 3642 } 3643 if (isa<BlockPointerType>(lhsType) && 3644 rhsType->getAs<PointerType>()->getPointeeType()->isVoidType()) 3645 return Compatible; 3646 return Incompatible; 3647 } 3648 3649 if (isa<TagType>(lhsType) && isa<TagType>(rhsType)) { 3650 if (Context.typesAreCompatible(lhsType, rhsType)) 3651 return Compatible; 3652 } 3653 return Incompatible; 3654} 3655 3656/// \brief Constructs a transparent union from an expression that is 3657/// used to initialize the transparent union. 3658static void ConstructTransparentUnion(ASTContext &C, Expr *&E, 3659 QualType UnionType, FieldDecl *Field) { 3660 // Build an initializer list that designates the appropriate member 3661 // of the transparent union. 3662 InitListExpr *Initializer = new (C) InitListExpr(SourceLocation(), 3663 &E, 1, 3664 SourceLocation()); 3665 Initializer->setType(UnionType); 3666 Initializer->setInitializedFieldInUnion(Field); 3667 3668 // Build a compound literal constructing a value of the transparent 3669 // union type from this initializer list. 3670 E = new (C) CompoundLiteralExpr(SourceLocation(), UnionType, Initializer, 3671 false); 3672} 3673 3674Sema::AssignConvertType 3675Sema::CheckTransparentUnionArgumentConstraints(QualType ArgType, Expr *&rExpr) { 3676 QualType FromType = rExpr->getType(); 3677 3678 // If the ArgType is a Union type, we want to handle a potential 3679 // transparent_union GCC extension. 3680 const RecordType *UT = ArgType->getAsUnionType(); 3681 if (!UT || !UT->getDecl()->hasAttr<TransparentUnionAttr>()) 3682 return Incompatible; 3683 3684 // The field to initialize within the transparent union. 3685 RecordDecl *UD = UT->getDecl(); 3686 FieldDecl *InitField = 0; 3687 // It's compatible if the expression matches any of the fields. 3688 for (RecordDecl::field_iterator it = UD->field_begin(), 3689 itend = UD->field_end(); 3690 it != itend; ++it) { 3691 if (it->getType()->isPointerType()) { 3692 // If the transparent union contains a pointer type, we allow: 3693 // 1) void pointer 3694 // 2) null pointer constant 3695 if (FromType->isPointerType()) 3696 if (FromType->getAs<PointerType>()->getPointeeType()->isVoidType()) { 3697 ImpCastExprToType(rExpr, it->getType()); 3698 InitField = *it; 3699 break; 3700 } 3701 3702 if (rExpr->isNullPointerConstant(Context)) { 3703 ImpCastExprToType(rExpr, it->getType()); 3704 InitField = *it; 3705 break; 3706 } 3707 } 3708 3709 if (CheckAssignmentConstraints(it->getType(), rExpr->getType()) 3710 == Compatible) { 3711 InitField = *it; 3712 break; 3713 } 3714 } 3715 3716 if (!InitField) 3717 return Incompatible; 3718 3719 ConstructTransparentUnion(Context, rExpr, ArgType, InitField); 3720 return Compatible; 3721} 3722 3723Sema::AssignConvertType 3724Sema::CheckSingleAssignmentConstraints(QualType lhsType, Expr *&rExpr) { 3725 if (getLangOptions().CPlusPlus) { 3726 if (!lhsType->isRecordType()) { 3727 // C++ 5.17p3: If the left operand is not of class type, the 3728 // expression is implicitly converted (C++ 4) to the 3729 // cv-unqualified type of the left operand. 3730 if (PerformImplicitConversion(rExpr, lhsType.getUnqualifiedType(), 3731 "assigning")) 3732 return Incompatible; 3733 return Compatible; 3734 } 3735 3736 // FIXME: Currently, we fall through and treat C++ classes like C 3737 // structures. 3738 } 3739 3740 // C99 6.5.16.1p1: the left operand is a pointer and the right is 3741 // a null pointer constant. 3742 if ((lhsType->isPointerType() || 3743 lhsType->isObjCObjectPointerType() || 3744 lhsType->isBlockPointerType()) 3745 && rExpr->isNullPointerConstant(Context)) { 3746 ImpCastExprToType(rExpr, lhsType); 3747 return Compatible; 3748 } 3749 3750 // This check seems unnatural, however it is necessary to ensure the proper 3751 // conversion of functions/arrays. If the conversion were done for all 3752 // DeclExpr's (created by ActOnIdentifierExpr), it would mess up the unary 3753 // expressions that surpress this implicit conversion (&, sizeof). 3754 // 3755 // Suppress this for references: C++ 8.5.3p5. 3756 if (!lhsType->isReferenceType()) 3757 DefaultFunctionArrayConversion(rExpr); 3758 3759 Sema::AssignConvertType result = 3760 CheckAssignmentConstraints(lhsType, rExpr->getType()); 3761 3762 // C99 6.5.16.1p2: The value of the right operand is converted to the 3763 // type of the assignment expression. 3764 // CheckAssignmentConstraints allows the left-hand side to be a reference, 3765 // so that we can use references in built-in functions even in C. 3766 // The getNonReferenceType() call makes sure that the resulting expression 3767 // does not have reference type. 3768 if (result != Incompatible && rExpr->getType() != lhsType) 3769 ImpCastExprToType(rExpr, lhsType.getNonReferenceType()); 3770 return result; 3771} 3772 3773QualType Sema::InvalidOperands(SourceLocation Loc, Expr *&lex, Expr *&rex) { 3774 Diag(Loc, diag::err_typecheck_invalid_operands) 3775 << lex->getType() << rex->getType() 3776 << lex->getSourceRange() << rex->getSourceRange(); 3777 return QualType(); 3778} 3779 3780inline QualType Sema::CheckVectorOperands(SourceLocation Loc, Expr *&lex, 3781 Expr *&rex) { 3782 // For conversion purposes, we ignore any qualifiers. 3783 // For example, "const float" and "float" are equivalent. 3784 QualType lhsType = 3785 Context.getCanonicalType(lex->getType()).getUnqualifiedType(); 3786 QualType rhsType = 3787 Context.getCanonicalType(rex->getType()).getUnqualifiedType(); 3788 3789 // If the vector types are identical, return. 3790 if (lhsType == rhsType) 3791 return lhsType; 3792 3793 // Handle the case of a vector & extvector type of the same size and element 3794 // type. It would be nice if we only had one vector type someday. 3795 if (getLangOptions().LaxVectorConversions) { 3796 // FIXME: Should we warn here? 3797 if (const VectorType *LV = lhsType->getAsVectorType()) { 3798 if (const VectorType *RV = rhsType->getAsVectorType()) 3799 if (LV->getElementType() == RV->getElementType() && 3800 LV->getNumElements() == RV->getNumElements()) { 3801 return lhsType->isExtVectorType() ? lhsType : rhsType; 3802 } 3803 } 3804 } 3805 3806 // Canonicalize the ExtVector to the LHS, remember if we swapped so we can 3807 // swap back (so that we don't reverse the inputs to a subtract, for instance. 3808 bool swapped = false; 3809 if (rhsType->isExtVectorType()) { 3810 swapped = true; 3811 std::swap(rex, lex); 3812 std::swap(rhsType, lhsType); 3813 } 3814 3815 // Handle the case of an ext vector and scalar. 3816 if (const ExtVectorType *LV = lhsType->getAsExtVectorType()) { 3817 QualType EltTy = LV->getElementType(); 3818 if (EltTy->isIntegralType() && rhsType->isIntegralType()) { 3819 if (Context.getIntegerTypeOrder(EltTy, rhsType) >= 0) { 3820 ImpCastExprToType(rex, lhsType); 3821 if (swapped) std::swap(rex, lex); 3822 return lhsType; 3823 } 3824 } 3825 if (EltTy->isRealFloatingType() && rhsType->isScalarType() && 3826 rhsType->isRealFloatingType()) { 3827 if (Context.getFloatingTypeOrder(EltTy, rhsType) >= 0) { 3828 ImpCastExprToType(rex, lhsType); 3829 if (swapped) std::swap(rex, lex); 3830 return lhsType; 3831 } 3832 } 3833 } 3834 3835 // Vectors of different size or scalar and non-ext-vector are errors. 3836 Diag(Loc, diag::err_typecheck_vector_not_convertable) 3837 << lex->getType() << rex->getType() 3838 << lex->getSourceRange() << rex->getSourceRange(); 3839 return QualType(); 3840} 3841 3842inline QualType Sema::CheckMultiplyDivideOperands( 3843 Expr *&lex, Expr *&rex, SourceLocation Loc, bool isCompAssign) 3844{ 3845 if (lex->getType()->isVectorType() || rex->getType()->isVectorType()) 3846 return CheckVectorOperands(Loc, lex, rex); 3847 3848 QualType compType = UsualArithmeticConversions(lex, rex, isCompAssign); 3849 3850 if (lex->getType()->isArithmeticType() && rex->getType()->isArithmeticType()) 3851 return compType; 3852 return InvalidOperands(Loc, lex, rex); 3853} 3854 3855inline QualType Sema::CheckRemainderOperands( 3856 Expr *&lex, Expr *&rex, SourceLocation Loc, bool isCompAssign) 3857{ 3858 if (lex->getType()->isVectorType() || rex->getType()->isVectorType()) { 3859 if (lex->getType()->isIntegerType() && rex->getType()->isIntegerType()) 3860 return CheckVectorOperands(Loc, lex, rex); 3861 return InvalidOperands(Loc, lex, rex); 3862 } 3863 3864 QualType compType = UsualArithmeticConversions(lex, rex, isCompAssign); 3865 3866 if (lex->getType()->isIntegerType() && rex->getType()->isIntegerType()) 3867 return compType; 3868 return InvalidOperands(Loc, lex, rex); 3869} 3870 3871inline QualType Sema::CheckAdditionOperands( // C99 6.5.6 3872 Expr *&lex, Expr *&rex, SourceLocation Loc, QualType* CompLHSTy) 3873{ 3874 if (lex->getType()->isVectorType() || rex->getType()->isVectorType()) { 3875 QualType compType = CheckVectorOperands(Loc, lex, rex); 3876 if (CompLHSTy) *CompLHSTy = compType; 3877 return compType; 3878 } 3879 3880 QualType compType = UsualArithmeticConversions(lex, rex, CompLHSTy); 3881 3882 // handle the common case first (both operands are arithmetic). 3883 if (lex->getType()->isArithmeticType() && 3884 rex->getType()->isArithmeticType()) { 3885 if (CompLHSTy) *CompLHSTy = compType; 3886 return compType; 3887 } 3888 3889 // Put any potential pointer into PExp 3890 Expr* PExp = lex, *IExp = rex; 3891 if (IExp->getType()->isAnyPointerType()) 3892 std::swap(PExp, IExp); 3893 3894 if (PExp->getType()->isAnyPointerType()) { 3895 3896 if (IExp->getType()->isIntegerType()) { 3897 QualType PointeeTy = PExp->getType()->getPointeeType(); 3898 3899 // Check for arithmetic on pointers to incomplete types. 3900 if (PointeeTy->isVoidType()) { 3901 if (getLangOptions().CPlusPlus) { 3902 Diag(Loc, diag::err_typecheck_pointer_arith_void_type) 3903 << lex->getSourceRange() << rex->getSourceRange(); 3904 return QualType(); 3905 } 3906 3907 // GNU extension: arithmetic on pointer to void 3908 Diag(Loc, diag::ext_gnu_void_ptr) 3909 << lex->getSourceRange() << rex->getSourceRange(); 3910 } else if (PointeeTy->isFunctionType()) { 3911 if (getLangOptions().CPlusPlus) { 3912 Diag(Loc, diag::err_typecheck_pointer_arith_function_type) 3913 << lex->getType() << lex->getSourceRange(); 3914 return QualType(); 3915 } 3916 3917 // GNU extension: arithmetic on pointer to function 3918 Diag(Loc, diag::ext_gnu_ptr_func_arith) 3919 << lex->getType() << lex->getSourceRange(); 3920 } else { 3921 // Check if we require a complete type. 3922 if (((PExp->getType()->isPointerType() && 3923 !PExp->getType()->isDependentType()) || 3924 PExp->getType()->isObjCObjectPointerType()) && 3925 RequireCompleteType(Loc, PointeeTy, 3926 diag::err_typecheck_arithmetic_incomplete_type, 3927 PExp->getSourceRange(), SourceRange(), 3928 PExp->getType())) 3929 return QualType(); 3930 } 3931 // Diagnose bad cases where we step over interface counts. 3932 if (PointeeTy->isObjCInterfaceType() && LangOpts.ObjCNonFragileABI) { 3933 Diag(Loc, diag::err_arithmetic_nonfragile_interface) 3934 << PointeeTy << PExp->getSourceRange(); 3935 return QualType(); 3936 } 3937 3938 if (CompLHSTy) { 3939 QualType LHSTy = Context.isPromotableBitField(lex); 3940 if (LHSTy.isNull()) { 3941 LHSTy = lex->getType(); 3942 if (LHSTy->isPromotableIntegerType()) 3943 LHSTy = Context.getPromotedIntegerType(LHSTy); 3944 } 3945 *CompLHSTy = LHSTy; 3946 } 3947 return PExp->getType(); 3948 } 3949 } 3950 3951 return InvalidOperands(Loc, lex, rex); 3952} 3953 3954// C99 6.5.6 3955QualType Sema::CheckSubtractionOperands(Expr *&lex, Expr *&rex, 3956 SourceLocation Loc, QualType* CompLHSTy) { 3957 if (lex->getType()->isVectorType() || rex->getType()->isVectorType()) { 3958 QualType compType = CheckVectorOperands(Loc, lex, rex); 3959 if (CompLHSTy) *CompLHSTy = compType; 3960 return compType; 3961 } 3962 3963 QualType compType = UsualArithmeticConversions(lex, rex, CompLHSTy); 3964 3965 // Enforce type constraints: C99 6.5.6p3. 3966 3967 // Handle the common case first (both operands are arithmetic). 3968 if (lex->getType()->isArithmeticType() 3969 && rex->getType()->isArithmeticType()) { 3970 if (CompLHSTy) *CompLHSTy = compType; 3971 return compType; 3972 } 3973 3974 // Either ptr - int or ptr - ptr. 3975 if (lex->getType()->isAnyPointerType()) { 3976 QualType lpointee = lex->getType()->getPointeeType(); 3977 3978 // The LHS must be an completely-defined object type. 3979 3980 bool ComplainAboutVoid = false; 3981 Expr *ComplainAboutFunc = 0; 3982 if (lpointee->isVoidType()) { 3983 if (getLangOptions().CPlusPlus) { 3984 Diag(Loc, diag::err_typecheck_pointer_arith_void_type) 3985 << lex->getSourceRange() << rex->getSourceRange(); 3986 return QualType(); 3987 } 3988 3989 // GNU C extension: arithmetic on pointer to void 3990 ComplainAboutVoid = true; 3991 } else if (lpointee->isFunctionType()) { 3992 if (getLangOptions().CPlusPlus) { 3993 Diag(Loc, diag::err_typecheck_pointer_arith_function_type) 3994 << lex->getType() << lex->getSourceRange(); 3995 return QualType(); 3996 } 3997 3998 // GNU C extension: arithmetic on pointer to function 3999 ComplainAboutFunc = lex; 4000 } else if (!lpointee->isDependentType() && 4001 RequireCompleteType(Loc, lpointee, 4002 diag::err_typecheck_sub_ptr_object, 4003 lex->getSourceRange(), 4004 SourceRange(), 4005 lex->getType())) 4006 return QualType(); 4007 4008 // Diagnose bad cases where we step over interface counts. 4009 if (lpointee->isObjCInterfaceType() && LangOpts.ObjCNonFragileABI) { 4010 Diag(Loc, diag::err_arithmetic_nonfragile_interface) 4011 << lpointee << lex->getSourceRange(); 4012 return QualType(); 4013 } 4014 4015 // The result type of a pointer-int computation is the pointer type. 4016 if (rex->getType()->isIntegerType()) { 4017 if (ComplainAboutVoid) 4018 Diag(Loc, diag::ext_gnu_void_ptr) 4019 << lex->getSourceRange() << rex->getSourceRange(); 4020 if (ComplainAboutFunc) 4021 Diag(Loc, diag::ext_gnu_ptr_func_arith) 4022 << ComplainAboutFunc->getType() 4023 << ComplainAboutFunc->getSourceRange(); 4024 4025 if (CompLHSTy) *CompLHSTy = lex->getType(); 4026 return lex->getType(); 4027 } 4028 4029 // Handle pointer-pointer subtractions. 4030 if (const PointerType *RHSPTy = rex->getType()->getAs<PointerType>()) { 4031 QualType rpointee = RHSPTy->getPointeeType(); 4032 4033 // RHS must be a completely-type object type. 4034 // Handle the GNU void* extension. 4035 if (rpointee->isVoidType()) { 4036 if (getLangOptions().CPlusPlus) { 4037 Diag(Loc, diag::err_typecheck_pointer_arith_void_type) 4038 << lex->getSourceRange() << rex->getSourceRange(); 4039 return QualType(); 4040 } 4041 4042 ComplainAboutVoid = true; 4043 } else if (rpointee->isFunctionType()) { 4044 if (getLangOptions().CPlusPlus) { 4045 Diag(Loc, diag::err_typecheck_pointer_arith_function_type) 4046 << rex->getType() << rex->getSourceRange(); 4047 return QualType(); 4048 } 4049 4050 // GNU extension: arithmetic on pointer to function 4051 if (!ComplainAboutFunc) 4052 ComplainAboutFunc = rex; 4053 } else if (!rpointee->isDependentType() && 4054 RequireCompleteType(Loc, rpointee, 4055 diag::err_typecheck_sub_ptr_object, 4056 rex->getSourceRange(), 4057 SourceRange(), 4058 rex->getType())) 4059 return QualType(); 4060 4061 if (getLangOptions().CPlusPlus) { 4062 // Pointee types must be the same: C++ [expr.add] 4063 if (!Context.hasSameUnqualifiedType(lpointee, rpointee)) { 4064 Diag(Loc, diag::err_typecheck_sub_ptr_compatible) 4065 << lex->getType() << rex->getType() 4066 << lex->getSourceRange() << rex->getSourceRange(); 4067 return QualType(); 4068 } 4069 } else { 4070 // Pointee types must be compatible C99 6.5.6p3 4071 if (!Context.typesAreCompatible( 4072 Context.getCanonicalType(lpointee).getUnqualifiedType(), 4073 Context.getCanonicalType(rpointee).getUnqualifiedType())) { 4074 Diag(Loc, diag::err_typecheck_sub_ptr_compatible) 4075 << lex->getType() << rex->getType() 4076 << lex->getSourceRange() << rex->getSourceRange(); 4077 return QualType(); 4078 } 4079 } 4080 4081 if (ComplainAboutVoid) 4082 Diag(Loc, diag::ext_gnu_void_ptr) 4083 << lex->getSourceRange() << rex->getSourceRange(); 4084 if (ComplainAboutFunc) 4085 Diag(Loc, diag::ext_gnu_ptr_func_arith) 4086 << ComplainAboutFunc->getType() 4087 << ComplainAboutFunc->getSourceRange(); 4088 4089 if (CompLHSTy) *CompLHSTy = lex->getType(); 4090 return Context.getPointerDiffType(); 4091 } 4092 } 4093 4094 return InvalidOperands(Loc, lex, rex); 4095} 4096 4097// C99 6.5.7 4098QualType Sema::CheckShiftOperands(Expr *&lex, Expr *&rex, SourceLocation Loc, 4099 bool isCompAssign) { 4100 // C99 6.5.7p2: Each of the operands shall have integer type. 4101 if (!lex->getType()->isIntegerType() || !rex->getType()->isIntegerType()) 4102 return InvalidOperands(Loc, lex, rex); 4103 4104 // Shifts don't perform usual arithmetic conversions, they just do integer 4105 // promotions on each operand. C99 6.5.7p3 4106 QualType LHSTy = Context.isPromotableBitField(lex); 4107 if (LHSTy.isNull()) { 4108 LHSTy = lex->getType(); 4109 if (LHSTy->isPromotableIntegerType()) 4110 LHSTy = Context.getPromotedIntegerType(LHSTy); 4111 } 4112 if (!isCompAssign) 4113 ImpCastExprToType(lex, LHSTy); 4114 4115 UsualUnaryConversions(rex); 4116 4117 // Sanity-check shift operands 4118 llvm::APSInt Right; 4119 // Check right/shifter operand 4120 if (rex->isIntegerConstantExpr(Right, Context)) { 4121 if (Right.isNegative()) 4122 Diag(Loc, diag::warn_shift_negative) << rex->getSourceRange(); 4123 else { 4124 llvm::APInt LeftBits(Right.getBitWidth(), 4125 Context.getTypeSize(lex->getType())); 4126 if (Right.uge(LeftBits)) 4127 Diag(Loc, diag::warn_shift_gt_typewidth) << rex->getSourceRange(); 4128 } 4129 } 4130 4131 // "The type of the result is that of the promoted left operand." 4132 return LHSTy; 4133} 4134 4135// C99 6.5.8, C++ [expr.rel] 4136QualType Sema::CheckCompareOperands(Expr *&lex, Expr *&rex, SourceLocation Loc, 4137 unsigned OpaqueOpc, bool isRelational) { 4138 BinaryOperator::Opcode Opc = (BinaryOperator::Opcode)OpaqueOpc; 4139 4140 if (lex->getType()->isVectorType() || rex->getType()->isVectorType()) 4141 return CheckVectorCompareOperands(lex, rex, Loc, isRelational); 4142 4143 // C99 6.5.8p3 / C99 6.5.9p4 4144 if (lex->getType()->isArithmeticType() && rex->getType()->isArithmeticType()) 4145 UsualArithmeticConversions(lex, rex); 4146 else { 4147 UsualUnaryConversions(lex); 4148 UsualUnaryConversions(rex); 4149 } 4150 QualType lType = lex->getType(); 4151 QualType rType = rex->getType(); 4152 4153 if (!lType->isFloatingType() 4154 && !(lType->isBlockPointerType() && isRelational)) { 4155 // For non-floating point types, check for self-comparisons of the form 4156 // x == x, x != x, x < x, etc. These always evaluate to a constant, and 4157 // often indicate logic errors in the program. 4158 // NOTE: Don't warn about comparisons of enum constants. These can arise 4159 // from macro expansions, and are usually quite deliberate. 4160 Expr *LHSStripped = lex->IgnoreParens(); 4161 Expr *RHSStripped = rex->IgnoreParens(); 4162 if (DeclRefExpr* DRL = dyn_cast<DeclRefExpr>(LHSStripped)) 4163 if (DeclRefExpr* DRR = dyn_cast<DeclRefExpr>(RHSStripped)) 4164 if (DRL->getDecl() == DRR->getDecl() && 4165 !isa<EnumConstantDecl>(DRL->getDecl())) 4166 Diag(Loc, diag::warn_selfcomparison); 4167 4168 if (isa<CastExpr>(LHSStripped)) 4169 LHSStripped = LHSStripped->IgnoreParenCasts(); 4170 if (isa<CastExpr>(RHSStripped)) 4171 RHSStripped = RHSStripped->IgnoreParenCasts(); 4172 4173 // Warn about comparisons against a string constant (unless the other 4174 // operand is null), the user probably wants strcmp. 4175 Expr *literalString = 0; 4176 Expr *literalStringStripped = 0; 4177 if ((isa<StringLiteral>(LHSStripped) || isa<ObjCEncodeExpr>(LHSStripped)) && 4178 !RHSStripped->isNullPointerConstant(Context)) { 4179 literalString = lex; 4180 literalStringStripped = LHSStripped; 4181 } else if ((isa<StringLiteral>(RHSStripped) || 4182 isa<ObjCEncodeExpr>(RHSStripped)) && 4183 !LHSStripped->isNullPointerConstant(Context)) { 4184 literalString = rex; 4185 literalStringStripped = RHSStripped; 4186 } 4187 4188 if (literalString) { 4189 std::string resultComparison; 4190 switch (Opc) { 4191 case BinaryOperator::LT: resultComparison = ") < 0"; break; 4192 case BinaryOperator::GT: resultComparison = ") > 0"; break; 4193 case BinaryOperator::LE: resultComparison = ") <= 0"; break; 4194 case BinaryOperator::GE: resultComparison = ") >= 0"; break; 4195 case BinaryOperator::EQ: resultComparison = ") == 0"; break; 4196 case BinaryOperator::NE: resultComparison = ") != 0"; break; 4197 default: assert(false && "Invalid comparison operator"); 4198 } 4199 Diag(Loc, diag::warn_stringcompare) 4200 << isa<ObjCEncodeExpr>(literalStringStripped) 4201 << literalString->getSourceRange() 4202 << CodeModificationHint::CreateReplacement(SourceRange(Loc), ", ") 4203 << CodeModificationHint::CreateInsertion(lex->getLocStart(), 4204 "strcmp(") 4205 << CodeModificationHint::CreateInsertion( 4206 PP.getLocForEndOfToken(rex->getLocEnd()), 4207 resultComparison); 4208 } 4209 } 4210 4211 // The result of comparisons is 'bool' in C++, 'int' in C. 4212 QualType ResultTy = getLangOptions().CPlusPlus? Context.BoolTy :Context.IntTy; 4213 4214 if (isRelational) { 4215 if (lType->isRealType() && rType->isRealType()) 4216 return ResultTy; 4217 } else { 4218 // Check for comparisons of floating point operands using != and ==. 4219 if (lType->isFloatingType()) { 4220 assert(rType->isFloatingType()); 4221 CheckFloatComparison(Loc,lex,rex); 4222 } 4223 4224 if (lType->isArithmeticType() && rType->isArithmeticType()) 4225 return ResultTy; 4226 } 4227 4228 bool LHSIsNull = lex->isNullPointerConstant(Context); 4229 bool RHSIsNull = rex->isNullPointerConstant(Context); 4230 4231 // All of the following pointer related warnings are GCC extensions, except 4232 // when handling null pointer constants. One day, we can consider making them 4233 // errors (when -pedantic-errors is enabled). 4234 if (lType->isPointerType() && rType->isPointerType()) { // C99 6.5.8p2 4235 QualType LCanPointeeTy = 4236 Context.getCanonicalType(lType->getAs<PointerType>()->getPointeeType()); 4237 QualType RCanPointeeTy = 4238 Context.getCanonicalType(rType->getAs<PointerType>()->getPointeeType()); 4239 4240 if (isRelational) { 4241 if (lType->isFunctionPointerType() || rType->isFunctionPointerType()) { 4242 Diag(Loc, diag::ext_typecheck_ordered_comparison_of_function_pointers) 4243 << lType << rType << lex->getSourceRange() << rex->getSourceRange(); 4244 } 4245 if (LCanPointeeTy->isVoidType() != RCanPointeeTy->isVoidType()) { 4246 Diag(Loc, diag::ext_typecheck_comparison_of_distinct_pointers) 4247 << lType << rType << lex->getSourceRange() << rex->getSourceRange(); 4248 } 4249 } else { 4250 if (lType->isFunctionPointerType() != rType->isFunctionPointerType()) { 4251 if (!LHSIsNull && !RHSIsNull) 4252 Diag(Loc, diag::ext_typecheck_comparison_of_distinct_pointers) 4253 << lType << rType << lex->getSourceRange() << rex->getSourceRange(); 4254 } 4255 } 4256 4257 // Simple check: if the pointee types are identical, we're done. 4258 if (LCanPointeeTy == RCanPointeeTy) 4259 return ResultTy; 4260 4261 if (getLangOptions().CPlusPlus) { 4262 // C++ [expr.rel]p2: 4263 // [...] Pointer conversions (4.10) and qualification 4264 // conversions (4.4) are performed on pointer operands (or on 4265 // a pointer operand and a null pointer constant) to bring 4266 // them to their composite pointer type. [...] 4267 // 4268 // C++ [expr.eq]p2 uses the same notion for (in)equality 4269 // comparisons of pointers. 4270 QualType T = FindCompositePointerType(lex, rex); 4271 if (T.isNull()) { 4272 Diag(Loc, diag::err_typecheck_comparison_of_distinct_pointers) 4273 << lType << rType << lex->getSourceRange() << rex->getSourceRange(); 4274 return QualType(); 4275 } 4276 4277 ImpCastExprToType(lex, T); 4278 ImpCastExprToType(rex, T); 4279 return ResultTy; 4280 } 4281 4282 if (!LHSIsNull && !RHSIsNull && // C99 6.5.9p2 4283 !LCanPointeeTy->isVoidType() && !RCanPointeeTy->isVoidType() && 4284 !Context.typesAreCompatible(LCanPointeeTy.getUnqualifiedType(), 4285 RCanPointeeTy.getUnqualifiedType())) { 4286 Diag(Loc, diag::ext_typecheck_comparison_of_distinct_pointers) 4287 << lType << rType << lex->getSourceRange() << rex->getSourceRange(); 4288 } 4289 ImpCastExprToType(rex, lType); // promote the pointer to pointer 4290 return ResultTy; 4291 } 4292 // C++ allows comparison of pointers with null pointer constants. 4293 if (getLangOptions().CPlusPlus) { 4294 if (lType->isPointerType() && RHSIsNull) { 4295 ImpCastExprToType(rex, lType); 4296 return ResultTy; 4297 } 4298 if (rType->isPointerType() && LHSIsNull) { 4299 ImpCastExprToType(lex, rType); 4300 return ResultTy; 4301 } 4302 // And comparison of nullptr_t with itself. 4303 if (lType->isNullPtrType() && rType->isNullPtrType()) 4304 return ResultTy; 4305 } 4306 // Handle block pointer types. 4307 if (!isRelational && lType->isBlockPointerType() && rType->isBlockPointerType()) { 4308 QualType lpointee = lType->getAs<BlockPointerType>()->getPointeeType(); 4309 QualType rpointee = rType->getAs<BlockPointerType>()->getPointeeType(); 4310 4311 if (!LHSIsNull && !RHSIsNull && 4312 !Context.typesAreCompatible(lpointee, rpointee)) { 4313 Diag(Loc, diag::err_typecheck_comparison_of_distinct_blocks) 4314 << lType << rType << lex->getSourceRange() << rex->getSourceRange(); 4315 } 4316 ImpCastExprToType(rex, lType); // promote the pointer to pointer 4317 return ResultTy; 4318 } 4319 // Allow block pointers to be compared with null pointer constants. 4320 if (!isRelational 4321 && ((lType->isBlockPointerType() && rType->isPointerType()) 4322 || (lType->isPointerType() && rType->isBlockPointerType()))) { 4323 if (!LHSIsNull && !RHSIsNull) { 4324 if (!((rType->isPointerType() && rType->getAs<PointerType>() 4325 ->getPointeeType()->isVoidType()) 4326 || (lType->isPointerType() && lType->getAs<PointerType>() 4327 ->getPointeeType()->isVoidType()))) 4328 Diag(Loc, diag::err_typecheck_comparison_of_distinct_blocks) 4329 << lType << rType << lex->getSourceRange() << rex->getSourceRange(); 4330 } 4331 ImpCastExprToType(rex, lType); // promote the pointer to pointer 4332 return ResultTy; 4333 } 4334 4335 if ((lType->isObjCObjectPointerType() || rType->isObjCObjectPointerType())) { 4336 if (lType->isPointerType() || rType->isPointerType()) { 4337 const PointerType *LPT = lType->getAs<PointerType>(); 4338 const PointerType *RPT = rType->getAs<PointerType>(); 4339 bool LPtrToVoid = LPT ? 4340 Context.getCanonicalType(LPT->getPointeeType())->isVoidType() : false; 4341 bool RPtrToVoid = RPT ? 4342 Context.getCanonicalType(RPT->getPointeeType())->isVoidType() : false; 4343 4344 if (!LPtrToVoid && !RPtrToVoid && 4345 !Context.typesAreCompatible(lType, rType)) { 4346 Diag(Loc, diag::ext_typecheck_comparison_of_distinct_pointers) 4347 << lType << rType << lex->getSourceRange() << rex->getSourceRange(); 4348 } 4349 ImpCastExprToType(rex, lType); 4350 return ResultTy; 4351 } 4352 if (lType->isObjCObjectPointerType() && rType->isObjCObjectPointerType()) { 4353 if (!Context.areComparableObjCPointerTypes(lType, rType)) { 4354 Diag(Loc, diag::ext_typecheck_comparison_of_distinct_pointers) 4355 << lType << rType << lex->getSourceRange() << rex->getSourceRange(); 4356 } 4357 ImpCastExprToType(rex, lType); 4358 return ResultTy; 4359 } 4360 } 4361 if (lType->isAnyPointerType() && rType->isIntegerType()) { 4362 if (isRelational) 4363 Diag(Loc, diag::ext_typecheck_ordered_comparison_of_pointer_integer) 4364 << lType << rType << lex->getSourceRange() << rex->getSourceRange(); 4365 else if (!RHSIsNull) 4366 Diag(Loc, diag::ext_typecheck_comparison_of_pointer_integer) 4367 << lType << rType << lex->getSourceRange() << rex->getSourceRange(); 4368 ImpCastExprToType(rex, lType); // promote the integer to pointer 4369 return ResultTy; 4370 } 4371 if (lType->isIntegerType() && rType->isAnyPointerType()) { 4372 if (isRelational) 4373 Diag(Loc, diag::ext_typecheck_ordered_comparison_of_pointer_integer) 4374 << lType << rType << lex->getSourceRange() << rex->getSourceRange(); 4375 else if (!LHSIsNull) 4376 Diag(Loc, diag::ext_typecheck_comparison_of_pointer_integer) 4377 << lType << rType << lex->getSourceRange() << rex->getSourceRange(); 4378 ImpCastExprToType(lex, rType); // promote the integer to pointer 4379 return ResultTy; 4380 } 4381 // Handle block pointers. 4382 if (!isRelational && RHSIsNull 4383 && lType->isBlockPointerType() && rType->isIntegerType()) { 4384 ImpCastExprToType(rex, lType); // promote the integer to pointer 4385 return ResultTy; 4386 } 4387 if (!isRelational && LHSIsNull 4388 && lType->isIntegerType() && rType->isBlockPointerType()) { 4389 ImpCastExprToType(lex, rType); // promote the integer to pointer 4390 return ResultTy; 4391 } 4392 return InvalidOperands(Loc, lex, rex); 4393} 4394 4395/// CheckVectorCompareOperands - vector comparisons are a clang extension that 4396/// operates on extended vector types. Instead of producing an IntTy result, 4397/// like a scalar comparison, a vector comparison produces a vector of integer 4398/// types. 4399QualType Sema::CheckVectorCompareOperands(Expr *&lex, Expr *&rex, 4400 SourceLocation Loc, 4401 bool isRelational) { 4402 // Check to make sure we're operating on vectors of the same type and width, 4403 // Allowing one side to be a scalar of element type. 4404 QualType vType = CheckVectorOperands(Loc, lex, rex); 4405 if (vType.isNull()) 4406 return vType; 4407 4408 QualType lType = lex->getType(); 4409 QualType rType = rex->getType(); 4410 4411 // For non-floating point types, check for self-comparisons of the form 4412 // x == x, x != x, x < x, etc. These always evaluate to a constant, and 4413 // often indicate logic errors in the program. 4414 if (!lType->isFloatingType()) { 4415 if (DeclRefExpr* DRL = dyn_cast<DeclRefExpr>(lex->IgnoreParens())) 4416 if (DeclRefExpr* DRR = dyn_cast<DeclRefExpr>(rex->IgnoreParens())) 4417 if (DRL->getDecl() == DRR->getDecl()) 4418 Diag(Loc, diag::warn_selfcomparison); 4419 } 4420 4421 // Check for comparisons of floating point operands using != and ==. 4422 if (!isRelational && lType->isFloatingType()) { 4423 assert (rType->isFloatingType()); 4424 CheckFloatComparison(Loc,lex,rex); 4425 } 4426 4427 // Return the type for the comparison, which is the same as vector type for 4428 // integer vectors, or an integer type of identical size and number of 4429 // elements for floating point vectors. 4430 if (lType->isIntegerType()) 4431 return lType; 4432 4433 const VectorType *VTy = lType->getAsVectorType(); 4434 unsigned TypeSize = Context.getTypeSize(VTy->getElementType()); 4435 if (TypeSize == Context.getTypeSize(Context.IntTy)) 4436 return Context.getExtVectorType(Context.IntTy, VTy->getNumElements()); 4437 if (TypeSize == Context.getTypeSize(Context.LongTy)) 4438 return Context.getExtVectorType(Context.LongTy, VTy->getNumElements()); 4439 4440 assert(TypeSize == Context.getTypeSize(Context.LongLongTy) && 4441 "Unhandled vector element size in vector compare"); 4442 return Context.getExtVectorType(Context.LongLongTy, VTy->getNumElements()); 4443} 4444 4445inline QualType Sema::CheckBitwiseOperands( 4446 Expr *&lex, Expr *&rex, SourceLocation Loc, bool isCompAssign) 4447{ 4448 if (lex->getType()->isVectorType() || rex->getType()->isVectorType()) 4449 return CheckVectorOperands(Loc, lex, rex); 4450 4451 QualType compType = UsualArithmeticConversions(lex, rex, isCompAssign); 4452 4453 if (lex->getType()->isIntegerType() && rex->getType()->isIntegerType()) 4454 return compType; 4455 return InvalidOperands(Loc, lex, rex); 4456} 4457 4458inline QualType Sema::CheckLogicalOperands( // C99 6.5.[13,14] 4459 Expr *&lex, Expr *&rex, SourceLocation Loc) 4460{ 4461 UsualUnaryConversions(lex); 4462 UsualUnaryConversions(rex); 4463 4464 if (lex->getType()->isScalarType() && rex->getType()->isScalarType()) 4465 return Context.IntTy; 4466 return InvalidOperands(Loc, lex, rex); 4467} 4468 4469/// IsReadonlyProperty - Verify that otherwise a valid l-value expression 4470/// is a read-only property; return true if so. A readonly property expression 4471/// depends on various declarations and thus must be treated specially. 4472/// 4473static bool IsReadonlyProperty(Expr *E, Sema &S) 4474{ 4475 if (E->getStmtClass() == Expr::ObjCPropertyRefExprClass) { 4476 const ObjCPropertyRefExpr* PropExpr = cast<ObjCPropertyRefExpr>(E); 4477 if (ObjCPropertyDecl *PDecl = PropExpr->getProperty()) { 4478 QualType BaseType = PropExpr->getBase()->getType(); 4479 if (const ObjCObjectPointerType *OPT = 4480 BaseType->getAsObjCInterfacePointerType()) 4481 if (ObjCInterfaceDecl *IFace = OPT->getInterfaceDecl()) 4482 if (S.isPropertyReadonly(PDecl, IFace)) 4483 return true; 4484 } 4485 } 4486 return false; 4487} 4488 4489/// CheckForModifiableLvalue - Verify that E is a modifiable lvalue. If not, 4490/// emit an error and return true. If so, return false. 4491static bool CheckForModifiableLvalue(Expr *E, SourceLocation Loc, Sema &S) { 4492 SourceLocation OrigLoc = Loc; 4493 Expr::isModifiableLvalueResult IsLV = E->isModifiableLvalue(S.Context, 4494 &Loc); 4495 if (IsLV == Expr::MLV_Valid && IsReadonlyProperty(E, S)) 4496 IsLV = Expr::MLV_ReadonlyProperty; 4497 if (IsLV == Expr::MLV_Valid) 4498 return false; 4499 4500 unsigned Diag = 0; 4501 bool NeedType = false; 4502 switch (IsLV) { // C99 6.5.16p2 4503 default: assert(0 && "Unknown result from isModifiableLvalue!"); 4504 case Expr::MLV_ConstQualified: Diag = diag::err_typecheck_assign_const; break; 4505 case Expr::MLV_ArrayType: 4506 Diag = diag::err_typecheck_array_not_modifiable_lvalue; 4507 NeedType = true; 4508 break; 4509 case Expr::MLV_NotObjectType: 4510 Diag = diag::err_typecheck_non_object_not_modifiable_lvalue; 4511 NeedType = true; 4512 break; 4513 case Expr::MLV_LValueCast: 4514 Diag = diag::err_typecheck_lvalue_casts_not_supported; 4515 break; 4516 case Expr::MLV_InvalidExpression: 4517 Diag = diag::err_typecheck_expression_not_modifiable_lvalue; 4518 break; 4519 case Expr::MLV_IncompleteType: 4520 case Expr::MLV_IncompleteVoidType: 4521 return S.RequireCompleteType(Loc, E->getType(), 4522 diag::err_typecheck_incomplete_type_not_modifiable_lvalue, 4523 E->getSourceRange()); 4524 case Expr::MLV_DuplicateVectorComponents: 4525 Diag = diag::err_typecheck_duplicate_vector_components_not_mlvalue; 4526 break; 4527 case Expr::MLV_NotBlockQualified: 4528 Diag = diag::err_block_decl_ref_not_modifiable_lvalue; 4529 break; 4530 case Expr::MLV_ReadonlyProperty: 4531 Diag = diag::error_readonly_property_assignment; 4532 break; 4533 case Expr::MLV_NoSetterProperty: 4534 Diag = diag::error_nosetter_property_assignment; 4535 break; 4536 } 4537 4538 SourceRange Assign; 4539 if (Loc != OrigLoc) 4540 Assign = SourceRange(OrigLoc, OrigLoc); 4541 if (NeedType) 4542 S.Diag(Loc, Diag) << E->getType() << E->getSourceRange() << Assign; 4543 else 4544 S.Diag(Loc, Diag) << E->getSourceRange() << Assign; 4545 return true; 4546} 4547 4548 4549 4550// C99 6.5.16.1 4551QualType Sema::CheckAssignmentOperands(Expr *LHS, Expr *&RHS, 4552 SourceLocation Loc, 4553 QualType CompoundType) { 4554 // Verify that LHS is a modifiable lvalue, and emit error if not. 4555 if (CheckForModifiableLvalue(LHS, Loc, *this)) 4556 return QualType(); 4557 4558 QualType LHSType = LHS->getType(); 4559 QualType RHSType = CompoundType.isNull() ? RHS->getType() : CompoundType; 4560 4561 AssignConvertType ConvTy; 4562 if (CompoundType.isNull()) { 4563 // Simple assignment "x = y". 4564 ConvTy = CheckSingleAssignmentConstraints(LHSType, RHS); 4565 // Special case of NSObject attributes on c-style pointer types. 4566 if (ConvTy == IncompatiblePointer && 4567 ((Context.isObjCNSObjectType(LHSType) && 4568 RHSType->isObjCObjectPointerType()) || 4569 (Context.isObjCNSObjectType(RHSType) && 4570 LHSType->isObjCObjectPointerType()))) 4571 ConvTy = Compatible; 4572 4573 // If the RHS is a unary plus or minus, check to see if they = and + are 4574 // right next to each other. If so, the user may have typo'd "x =+ 4" 4575 // instead of "x += 4". 4576 Expr *RHSCheck = RHS; 4577 if (ImplicitCastExpr *ICE = dyn_cast<ImplicitCastExpr>(RHSCheck)) 4578 RHSCheck = ICE->getSubExpr(); 4579 if (UnaryOperator *UO = dyn_cast<UnaryOperator>(RHSCheck)) { 4580 if ((UO->getOpcode() == UnaryOperator::Plus || 4581 UO->getOpcode() == UnaryOperator::Minus) && 4582 Loc.isFileID() && UO->getOperatorLoc().isFileID() && 4583 // Only if the two operators are exactly adjacent. 4584 Loc.getFileLocWithOffset(1) == UO->getOperatorLoc() && 4585 // And there is a space or other character before the subexpr of the 4586 // unary +/-. We don't want to warn on "x=-1". 4587 Loc.getFileLocWithOffset(2) != UO->getSubExpr()->getLocStart() && 4588 UO->getSubExpr()->getLocStart().isFileID()) { 4589 Diag(Loc, diag::warn_not_compound_assign) 4590 << (UO->getOpcode() == UnaryOperator::Plus ? "+" : "-") 4591 << SourceRange(UO->getOperatorLoc(), UO->getOperatorLoc()); 4592 } 4593 } 4594 } else { 4595 // Compound assignment "x += y" 4596 ConvTy = CheckAssignmentConstraints(LHSType, RHSType); 4597 } 4598 4599 if (DiagnoseAssignmentResult(ConvTy, Loc, LHSType, RHSType, 4600 RHS, "assigning")) 4601 return QualType(); 4602 4603 // C99 6.5.16p3: The type of an assignment expression is the type of the 4604 // left operand unless the left operand has qualified type, in which case 4605 // it is the unqualified version of the type of the left operand. 4606 // C99 6.5.16.1p2: In simple assignment, the value of the right operand 4607 // is converted to the type of the assignment expression (above). 4608 // C++ 5.17p1: the type of the assignment expression is that of its left 4609 // operand. 4610 return LHSType.getUnqualifiedType(); 4611} 4612 4613// C99 6.5.17 4614QualType Sema::CheckCommaOperands(Expr *LHS, Expr *&RHS, SourceLocation Loc) { 4615 // Comma performs lvalue conversion (C99 6.3.2.1), but not unary conversions. 4616 DefaultFunctionArrayConversion(RHS); 4617 4618 // FIXME: Check that RHS type is complete in C mode (it's legal for it to be 4619 // incomplete in C++). 4620 4621 return RHS->getType(); 4622} 4623 4624/// CheckIncrementDecrementOperand - unlike most "Check" methods, this routine 4625/// doesn't need to call UsualUnaryConversions or UsualArithmeticConversions. 4626QualType Sema::CheckIncrementDecrementOperand(Expr *Op, SourceLocation OpLoc, 4627 bool isInc) { 4628 if (Op->isTypeDependent()) 4629 return Context.DependentTy; 4630 4631 QualType ResType = Op->getType(); 4632 assert(!ResType.isNull() && "no type for increment/decrement expression"); 4633 4634 if (getLangOptions().CPlusPlus && ResType->isBooleanType()) { 4635 // Decrement of bool is not allowed. 4636 if (!isInc) { 4637 Diag(OpLoc, diag::err_decrement_bool) << Op->getSourceRange(); 4638 return QualType(); 4639 } 4640 // Increment of bool sets it to true, but is deprecated. 4641 Diag(OpLoc, diag::warn_increment_bool) << Op->getSourceRange(); 4642 } else if (ResType->isRealType()) { 4643 // OK! 4644 } else if (ResType->isAnyPointerType()) { 4645 QualType PointeeTy = ResType->getPointeeType(); 4646 4647 // C99 6.5.2.4p2, 6.5.6p2 4648 if (PointeeTy->isVoidType()) { 4649 if (getLangOptions().CPlusPlus) { 4650 Diag(OpLoc, diag::err_typecheck_pointer_arith_void_type) 4651 << Op->getSourceRange(); 4652 return QualType(); 4653 } 4654 4655 // Pointer to void is a GNU extension in C. 4656 Diag(OpLoc, diag::ext_gnu_void_ptr) << Op->getSourceRange(); 4657 } else if (PointeeTy->isFunctionType()) { 4658 if (getLangOptions().CPlusPlus) { 4659 Diag(OpLoc, diag::err_typecheck_pointer_arith_function_type) 4660 << Op->getType() << Op->getSourceRange(); 4661 return QualType(); 4662 } 4663 4664 Diag(OpLoc, diag::ext_gnu_ptr_func_arith) 4665 << ResType << Op->getSourceRange(); 4666 } else if (RequireCompleteType(OpLoc, PointeeTy, 4667 diag::err_typecheck_arithmetic_incomplete_type, 4668 Op->getSourceRange(), SourceRange(), 4669 ResType)) 4670 return QualType(); 4671 // Diagnose bad cases where we step over interface counts. 4672 else if (PointeeTy->isObjCInterfaceType() && LangOpts.ObjCNonFragileABI) { 4673 Diag(OpLoc, diag::err_arithmetic_nonfragile_interface) 4674 << PointeeTy << Op->getSourceRange(); 4675 return QualType(); 4676 } 4677 } else if (ResType->isComplexType()) { 4678 // C99 does not support ++/-- on complex types, we allow as an extension. 4679 Diag(OpLoc, diag::ext_integer_increment_complex) 4680 << ResType << Op->getSourceRange(); 4681 } else { 4682 Diag(OpLoc, diag::err_typecheck_illegal_increment_decrement) 4683 << ResType << Op->getSourceRange(); 4684 return QualType(); 4685 } 4686 // At this point, we know we have a real, complex or pointer type. 4687 // Now make sure the operand is a modifiable lvalue. 4688 if (CheckForModifiableLvalue(Op, OpLoc, *this)) 4689 return QualType(); 4690 return ResType; 4691} 4692 4693/// getPrimaryDecl - Helper function for CheckAddressOfOperand(). 4694/// This routine allows us to typecheck complex/recursive expressions 4695/// where the declaration is needed for type checking. We only need to 4696/// handle cases when the expression references a function designator 4697/// or is an lvalue. Here are some examples: 4698/// - &(x) => x 4699/// - &*****f => f for f a function designator. 4700/// - &s.xx => s 4701/// - &s.zz[1].yy -> s, if zz is an array 4702/// - *(x + 1) -> x, if x is an array 4703/// - &"123"[2] -> 0 4704/// - & __real__ x -> x 4705static NamedDecl *getPrimaryDecl(Expr *E) { 4706 switch (E->getStmtClass()) { 4707 case Stmt::DeclRefExprClass: 4708 case Stmt::QualifiedDeclRefExprClass: 4709 return cast<DeclRefExpr>(E)->getDecl(); 4710 case Stmt::MemberExprClass: 4711 // If this is an arrow operator, the address is an offset from 4712 // the base's value, so the object the base refers to is 4713 // irrelevant. 4714 if (cast<MemberExpr>(E)->isArrow()) 4715 return 0; 4716 // Otherwise, the expression refers to a part of the base 4717 return getPrimaryDecl(cast<MemberExpr>(E)->getBase()); 4718 case Stmt::ArraySubscriptExprClass: { 4719 // FIXME: This code shouldn't be necessary! We should catch the implicit 4720 // promotion of register arrays earlier. 4721 Expr* Base = cast<ArraySubscriptExpr>(E)->getBase(); 4722 if (ImplicitCastExpr* ICE = dyn_cast<ImplicitCastExpr>(Base)) { 4723 if (ICE->getSubExpr()->getType()->isArrayType()) 4724 return getPrimaryDecl(ICE->getSubExpr()); 4725 } 4726 return 0; 4727 } 4728 case Stmt::UnaryOperatorClass: { 4729 UnaryOperator *UO = cast<UnaryOperator>(E); 4730 4731 switch(UO->getOpcode()) { 4732 case UnaryOperator::Real: 4733 case UnaryOperator::Imag: 4734 case UnaryOperator::Extension: 4735 return getPrimaryDecl(UO->getSubExpr()); 4736 default: 4737 return 0; 4738 } 4739 } 4740 case Stmt::ParenExprClass: 4741 return getPrimaryDecl(cast<ParenExpr>(E)->getSubExpr()); 4742 case Stmt::ImplicitCastExprClass: 4743 // If the result of an implicit cast is an l-value, we care about 4744 // the sub-expression; otherwise, the result here doesn't matter. 4745 return getPrimaryDecl(cast<ImplicitCastExpr>(E)->getSubExpr()); 4746 default: 4747 return 0; 4748 } 4749} 4750 4751/// CheckAddressOfOperand - The operand of & must be either a function 4752/// designator or an lvalue designating an object. If it is an lvalue, the 4753/// object cannot be declared with storage class register or be a bit field. 4754/// Note: The usual conversions are *not* applied to the operand of the & 4755/// operator (C99 6.3.2.1p[2-4]), and its result is never an lvalue. 4756/// In C++, the operand might be an overloaded function name, in which case 4757/// we allow the '&' but retain the overloaded-function type. 4758QualType Sema::CheckAddressOfOperand(Expr *op, SourceLocation OpLoc) { 4759 // Make sure to ignore parentheses in subsequent checks 4760 op = op->IgnoreParens(); 4761 4762 if (op->isTypeDependent()) 4763 return Context.DependentTy; 4764 4765 if (getLangOptions().C99) { 4766 // Implement C99-only parts of addressof rules. 4767 if (UnaryOperator* uOp = dyn_cast<UnaryOperator>(op)) { 4768 if (uOp->getOpcode() == UnaryOperator::Deref) 4769 // Per C99 6.5.3.2, the address of a deref always returns a valid result 4770 // (assuming the deref expression is valid). 4771 return uOp->getSubExpr()->getType(); 4772 } 4773 // Technically, there should be a check for array subscript 4774 // expressions here, but the result of one is always an lvalue anyway. 4775 } 4776 NamedDecl *dcl = getPrimaryDecl(op); 4777 Expr::isLvalueResult lval = op->isLvalue(Context); 4778 4779 if (lval != Expr::LV_Valid && lval != Expr::LV_IncompleteVoidType) { 4780 // C99 6.5.3.2p1 4781 // The operand must be either an l-value or a function designator 4782 if (!op->getType()->isFunctionType()) { 4783 // FIXME: emit more specific diag... 4784 Diag(OpLoc, diag::err_typecheck_invalid_lvalue_addrof) 4785 << op->getSourceRange(); 4786 return QualType(); 4787 } 4788 } else if (op->getBitField()) { // C99 6.5.3.2p1 4789 // The operand cannot be a bit-field 4790 Diag(OpLoc, diag::err_typecheck_address_of) 4791 << "bit-field" << op->getSourceRange(); 4792 return QualType(); 4793 } else if (isa<ExtVectorElementExpr>(op) || (isa<ArraySubscriptExpr>(op) && 4794 cast<ArraySubscriptExpr>(op)->getBase()->getType()->isVectorType())){ 4795 // The operand cannot be an element of a vector 4796 Diag(OpLoc, diag::err_typecheck_address_of) 4797 << "vector element" << op->getSourceRange(); 4798 return QualType(); 4799 } else if (isa<ObjCPropertyRefExpr>(op)) { 4800 // cannot take address of a property expression. 4801 Diag(OpLoc, diag::err_typecheck_address_of) 4802 << "property expression" << op->getSourceRange(); 4803 return QualType(); 4804 } else if (dcl) { // C99 6.5.3.2p1 4805 // We have an lvalue with a decl. Make sure the decl is not declared 4806 // with the register storage-class specifier. 4807 if (const VarDecl *vd = dyn_cast<VarDecl>(dcl)) { 4808 if (vd->getStorageClass() == VarDecl::Register) { 4809 Diag(OpLoc, diag::err_typecheck_address_of) 4810 << "register variable" << op->getSourceRange(); 4811 return QualType(); 4812 } 4813 } else if (isa<OverloadedFunctionDecl>(dcl) || 4814 isa<FunctionTemplateDecl>(dcl)) { 4815 return Context.OverloadTy; 4816 } else if (FieldDecl *FD = dyn_cast<FieldDecl>(dcl)) { 4817 // Okay: we can take the address of a field. 4818 // Could be a pointer to member, though, if there is an explicit 4819 // scope qualifier for the class. 4820 if (isa<QualifiedDeclRefExpr>(op)) { 4821 DeclContext *Ctx = dcl->getDeclContext(); 4822 if (Ctx && Ctx->isRecord()) { 4823 if (FD->getType()->isReferenceType()) { 4824 Diag(OpLoc, 4825 diag::err_cannot_form_pointer_to_member_of_reference_type) 4826 << FD->getDeclName() << FD->getType(); 4827 return QualType(); 4828 } 4829 4830 return Context.getMemberPointerType(op->getType(), 4831 Context.getTypeDeclType(cast<RecordDecl>(Ctx)).getTypePtr()); 4832 } 4833 } 4834 } else if (CXXMethodDecl *MD = dyn_cast<CXXMethodDecl>(dcl)) { 4835 // Okay: we can take the address of a function. 4836 // As above. 4837 if (isa<QualifiedDeclRefExpr>(op) && MD->isInstance()) 4838 return Context.getMemberPointerType(op->getType(), 4839 Context.getTypeDeclType(MD->getParent()).getTypePtr()); 4840 } else if (!isa<FunctionDecl>(dcl)) 4841 assert(0 && "Unknown/unexpected decl type"); 4842 } 4843 4844 if (lval == Expr::LV_IncompleteVoidType) { 4845 // Taking the address of a void variable is technically illegal, but we 4846 // allow it in cases which are otherwise valid. 4847 // Example: "extern void x; void* y = &x;". 4848 Diag(OpLoc, diag::ext_typecheck_addrof_void) << op->getSourceRange(); 4849 } 4850 4851 // If the operand has type "type", the result has type "pointer to type". 4852 return Context.getPointerType(op->getType()); 4853} 4854 4855QualType Sema::CheckIndirectionOperand(Expr *Op, SourceLocation OpLoc) { 4856 if (Op->isTypeDependent()) 4857 return Context.DependentTy; 4858 4859 UsualUnaryConversions(Op); 4860 QualType Ty = Op->getType(); 4861 4862 // Note that per both C89 and C99, this is always legal, even if ptype is an 4863 // incomplete type or void. It would be possible to warn about dereferencing 4864 // a void pointer, but it's completely well-defined, and such a warning is 4865 // unlikely to catch any mistakes. 4866 if (const PointerType *PT = Ty->getAs<PointerType>()) 4867 return PT->getPointeeType(); 4868 4869 if (const ObjCObjectPointerType *OPT = Ty->getAsObjCObjectPointerType()) 4870 return OPT->getPointeeType(); 4871 4872 Diag(OpLoc, diag::err_typecheck_indirection_requires_pointer) 4873 << Ty << Op->getSourceRange(); 4874 return QualType(); 4875} 4876 4877static inline BinaryOperator::Opcode ConvertTokenKindToBinaryOpcode( 4878 tok::TokenKind Kind) { 4879 BinaryOperator::Opcode Opc; 4880 switch (Kind) { 4881 default: assert(0 && "Unknown binop!"); 4882 case tok::periodstar: Opc = BinaryOperator::PtrMemD; break; 4883 case tok::arrowstar: Opc = BinaryOperator::PtrMemI; break; 4884 case tok::star: Opc = BinaryOperator::Mul; break; 4885 case tok::slash: Opc = BinaryOperator::Div; break; 4886 case tok::percent: Opc = BinaryOperator::Rem; break; 4887 case tok::plus: Opc = BinaryOperator::Add; break; 4888 case tok::minus: Opc = BinaryOperator::Sub; break; 4889 case tok::lessless: Opc = BinaryOperator::Shl; break; 4890 case tok::greatergreater: Opc = BinaryOperator::Shr; break; 4891 case tok::lessequal: Opc = BinaryOperator::LE; break; 4892 case tok::less: Opc = BinaryOperator::LT; break; 4893 case tok::greaterequal: Opc = BinaryOperator::GE; break; 4894 case tok::greater: Opc = BinaryOperator::GT; break; 4895 case tok::exclaimequal: Opc = BinaryOperator::NE; break; 4896 case tok::equalequal: Opc = BinaryOperator::EQ; break; 4897 case tok::amp: Opc = BinaryOperator::And; break; 4898 case tok::caret: Opc = BinaryOperator::Xor; break; 4899 case tok::pipe: Opc = BinaryOperator::Or; break; 4900 case tok::ampamp: Opc = BinaryOperator::LAnd; break; 4901 case tok::pipepipe: Opc = BinaryOperator::LOr; break; 4902 case tok::equal: Opc = BinaryOperator::Assign; break; 4903 case tok::starequal: Opc = BinaryOperator::MulAssign; break; 4904 case tok::slashequal: Opc = BinaryOperator::DivAssign; break; 4905 case tok::percentequal: Opc = BinaryOperator::RemAssign; break; 4906 case tok::plusequal: Opc = BinaryOperator::AddAssign; break; 4907 case tok::minusequal: Opc = BinaryOperator::SubAssign; break; 4908 case tok::lesslessequal: Opc = BinaryOperator::ShlAssign; break; 4909 case tok::greatergreaterequal: Opc = BinaryOperator::ShrAssign; break; 4910 case tok::ampequal: Opc = BinaryOperator::AndAssign; break; 4911 case tok::caretequal: Opc = BinaryOperator::XorAssign; break; 4912 case tok::pipeequal: Opc = BinaryOperator::OrAssign; break; 4913 case tok::comma: Opc = BinaryOperator::Comma; break; 4914 } 4915 return Opc; 4916} 4917 4918static inline UnaryOperator::Opcode ConvertTokenKindToUnaryOpcode( 4919 tok::TokenKind Kind) { 4920 UnaryOperator::Opcode Opc; 4921 switch (Kind) { 4922 default: assert(0 && "Unknown unary op!"); 4923 case tok::plusplus: Opc = UnaryOperator::PreInc; break; 4924 case tok::minusminus: Opc = UnaryOperator::PreDec; break; 4925 case tok::amp: Opc = UnaryOperator::AddrOf; break; 4926 case tok::star: Opc = UnaryOperator::Deref; break; 4927 case tok::plus: Opc = UnaryOperator::Plus; break; 4928 case tok::minus: Opc = UnaryOperator::Minus; break; 4929 case tok::tilde: Opc = UnaryOperator::Not; break; 4930 case tok::exclaim: Opc = UnaryOperator::LNot; break; 4931 case tok::kw___real: Opc = UnaryOperator::Real; break; 4932 case tok::kw___imag: Opc = UnaryOperator::Imag; break; 4933 case tok::kw___extension__: Opc = UnaryOperator::Extension; break; 4934 } 4935 return Opc; 4936} 4937 4938/// CreateBuiltinBinOp - Creates a new built-in binary operation with 4939/// operator @p Opc at location @c TokLoc. This routine only supports 4940/// built-in operations; ActOnBinOp handles overloaded operators. 4941Action::OwningExprResult Sema::CreateBuiltinBinOp(SourceLocation OpLoc, 4942 unsigned Op, 4943 Expr *lhs, Expr *rhs) { 4944 QualType ResultTy; // Result type of the binary operator. 4945 BinaryOperator::Opcode Opc = (BinaryOperator::Opcode)Op; 4946 // The following two variables are used for compound assignment operators 4947 QualType CompLHSTy; // Type of LHS after promotions for computation 4948 QualType CompResultTy; // Type of computation result 4949 4950 switch (Opc) { 4951 case BinaryOperator::Assign: 4952 ResultTy = CheckAssignmentOperands(lhs, rhs, OpLoc, QualType()); 4953 break; 4954 case BinaryOperator::PtrMemD: 4955 case BinaryOperator::PtrMemI: 4956 ResultTy = CheckPointerToMemberOperands(lhs, rhs, OpLoc, 4957 Opc == BinaryOperator::PtrMemI); 4958 break; 4959 case BinaryOperator::Mul: 4960 case BinaryOperator::Div: 4961 ResultTy = CheckMultiplyDivideOperands(lhs, rhs, OpLoc); 4962 break; 4963 case BinaryOperator::Rem: 4964 ResultTy = CheckRemainderOperands(lhs, rhs, OpLoc); 4965 break; 4966 case BinaryOperator::Add: 4967 ResultTy = CheckAdditionOperands(lhs, rhs, OpLoc); 4968 break; 4969 case BinaryOperator::Sub: 4970 ResultTy = CheckSubtractionOperands(lhs, rhs, OpLoc); 4971 break; 4972 case BinaryOperator::Shl: 4973 case BinaryOperator::Shr: 4974 ResultTy = CheckShiftOperands(lhs, rhs, OpLoc); 4975 break; 4976 case BinaryOperator::LE: 4977 case BinaryOperator::LT: 4978 case BinaryOperator::GE: 4979 case BinaryOperator::GT: 4980 ResultTy = CheckCompareOperands(lhs, rhs, OpLoc, Opc, true); 4981 break; 4982 case BinaryOperator::EQ: 4983 case BinaryOperator::NE: 4984 ResultTy = CheckCompareOperands(lhs, rhs, OpLoc, Opc, false); 4985 break; 4986 case BinaryOperator::And: 4987 case BinaryOperator::Xor: 4988 case BinaryOperator::Or: 4989 ResultTy = CheckBitwiseOperands(lhs, rhs, OpLoc); 4990 break; 4991 case BinaryOperator::LAnd: 4992 case BinaryOperator::LOr: 4993 ResultTy = CheckLogicalOperands(lhs, rhs, OpLoc); 4994 break; 4995 case BinaryOperator::MulAssign: 4996 case BinaryOperator::DivAssign: 4997 CompResultTy = CheckMultiplyDivideOperands(lhs, rhs, OpLoc, true); 4998 CompLHSTy = CompResultTy; 4999 if (!CompResultTy.isNull()) 5000 ResultTy = CheckAssignmentOperands(lhs, rhs, OpLoc, CompResultTy); 5001 break; 5002 case BinaryOperator::RemAssign: 5003 CompResultTy = CheckRemainderOperands(lhs, rhs, OpLoc, true); 5004 CompLHSTy = CompResultTy; 5005 if (!CompResultTy.isNull()) 5006 ResultTy = CheckAssignmentOperands(lhs, rhs, OpLoc, CompResultTy); 5007 break; 5008 case BinaryOperator::AddAssign: 5009 CompResultTy = CheckAdditionOperands(lhs, rhs, OpLoc, &CompLHSTy); 5010 if (!CompResultTy.isNull()) 5011 ResultTy = CheckAssignmentOperands(lhs, rhs, OpLoc, CompResultTy); 5012 break; 5013 case BinaryOperator::SubAssign: 5014 CompResultTy = CheckSubtractionOperands(lhs, rhs, OpLoc, &CompLHSTy); 5015 if (!CompResultTy.isNull()) 5016 ResultTy = CheckAssignmentOperands(lhs, rhs, OpLoc, CompResultTy); 5017 break; 5018 case BinaryOperator::ShlAssign: 5019 case BinaryOperator::ShrAssign: 5020 CompResultTy = CheckShiftOperands(lhs, rhs, OpLoc, true); 5021 CompLHSTy = CompResultTy; 5022 if (!CompResultTy.isNull()) 5023 ResultTy = CheckAssignmentOperands(lhs, rhs, OpLoc, CompResultTy); 5024 break; 5025 case BinaryOperator::AndAssign: 5026 case BinaryOperator::XorAssign: 5027 case BinaryOperator::OrAssign: 5028 CompResultTy = CheckBitwiseOperands(lhs, rhs, OpLoc, true); 5029 CompLHSTy = CompResultTy; 5030 if (!CompResultTy.isNull()) 5031 ResultTy = CheckAssignmentOperands(lhs, rhs, OpLoc, CompResultTy); 5032 break; 5033 case BinaryOperator::Comma: 5034 ResultTy = CheckCommaOperands(lhs, rhs, OpLoc); 5035 break; 5036 } 5037 if (ResultTy.isNull()) 5038 return ExprError(); 5039 if (CompResultTy.isNull()) 5040 return Owned(new (Context) BinaryOperator(lhs, rhs, Opc, ResultTy, OpLoc)); 5041 else 5042 return Owned(new (Context) CompoundAssignOperator(lhs, rhs, Opc, ResultTy, 5043 CompLHSTy, CompResultTy, 5044 OpLoc)); 5045} 5046 5047// Binary Operators. 'Tok' is the token for the operator. 5048Action::OwningExprResult Sema::ActOnBinOp(Scope *S, SourceLocation TokLoc, 5049 tok::TokenKind Kind, 5050 ExprArg LHS, ExprArg RHS) { 5051 BinaryOperator::Opcode Opc = ConvertTokenKindToBinaryOpcode(Kind); 5052 Expr *lhs = LHS.takeAs<Expr>(), *rhs = RHS.takeAs<Expr>(); 5053 5054 assert((lhs != 0) && "ActOnBinOp(): missing left expression"); 5055 assert((rhs != 0) && "ActOnBinOp(): missing right expression"); 5056 5057 if (getLangOptions().CPlusPlus && 5058 (lhs->getType()->isOverloadableType() || 5059 rhs->getType()->isOverloadableType())) { 5060 // Find all of the overloaded operators visible from this 5061 // point. We perform both an operator-name lookup from the local 5062 // scope and an argument-dependent lookup based on the types of 5063 // the arguments. 5064 FunctionSet Functions; 5065 OverloadedOperatorKind OverOp = BinaryOperator::getOverloadedOperator(Opc); 5066 if (OverOp != OO_None) { 5067 LookupOverloadedOperatorName(OverOp, S, lhs->getType(), rhs->getType(), 5068 Functions); 5069 Expr *Args[2] = { lhs, rhs }; 5070 DeclarationName OpName 5071 = Context.DeclarationNames.getCXXOperatorName(OverOp); 5072 ArgumentDependentLookup(OpName, Args, 2, Functions); 5073 } 5074 5075 // Build the (potentially-overloaded, potentially-dependent) 5076 // binary operation. 5077 return CreateOverloadedBinOp(TokLoc, Opc, Functions, lhs, rhs); 5078 } 5079 5080 // Build a built-in binary operation. 5081 return CreateBuiltinBinOp(TokLoc, Opc, lhs, rhs); 5082} 5083 5084Action::OwningExprResult Sema::CreateBuiltinUnaryOp(SourceLocation OpLoc, 5085 unsigned OpcIn, 5086 ExprArg InputArg) { 5087 UnaryOperator::Opcode Opc = static_cast<UnaryOperator::Opcode>(OpcIn); 5088 5089 // FIXME: Input is modified below, but InputArg is not updated appropriately. 5090 Expr *Input = (Expr *)InputArg.get(); 5091 QualType resultType; 5092 switch (Opc) { 5093 case UnaryOperator::OffsetOf: 5094 assert(false && "Invalid unary operator"); 5095 break; 5096 5097 case UnaryOperator::PreInc: 5098 case UnaryOperator::PreDec: 5099 case UnaryOperator::PostInc: 5100 case UnaryOperator::PostDec: 5101 resultType = CheckIncrementDecrementOperand(Input, OpLoc, 5102 Opc == UnaryOperator::PreInc || 5103 Opc == UnaryOperator::PostInc); 5104 break; 5105 case UnaryOperator::AddrOf: 5106 resultType = CheckAddressOfOperand(Input, OpLoc); 5107 break; 5108 case UnaryOperator::Deref: 5109 DefaultFunctionArrayConversion(Input); 5110 resultType = CheckIndirectionOperand(Input, OpLoc); 5111 break; 5112 case UnaryOperator::Plus: 5113 case UnaryOperator::Minus: 5114 UsualUnaryConversions(Input); 5115 resultType = Input->getType(); 5116 if (resultType->isDependentType()) 5117 break; 5118 if (resultType->isArithmeticType()) // C99 6.5.3.3p1 5119 break; 5120 else if (getLangOptions().CPlusPlus && // C++ [expr.unary.op]p6-7 5121 resultType->isEnumeralType()) 5122 break; 5123 else if (getLangOptions().CPlusPlus && // C++ [expr.unary.op]p6 5124 Opc == UnaryOperator::Plus && 5125 resultType->isPointerType()) 5126 break; 5127 5128 return ExprError(Diag(OpLoc, diag::err_typecheck_unary_expr) 5129 << resultType << Input->getSourceRange()); 5130 case UnaryOperator::Not: // bitwise complement 5131 UsualUnaryConversions(Input); 5132 resultType = Input->getType(); 5133 if (resultType->isDependentType()) 5134 break; 5135 // C99 6.5.3.3p1. We allow complex int and float as a GCC extension. 5136 if (resultType->isComplexType() || resultType->isComplexIntegerType()) 5137 // C99 does not support '~' for complex conjugation. 5138 Diag(OpLoc, diag::ext_integer_complement_complex) 5139 << resultType << Input->getSourceRange(); 5140 else if (!resultType->isIntegerType()) 5141 return ExprError(Diag(OpLoc, diag::err_typecheck_unary_expr) 5142 << resultType << Input->getSourceRange()); 5143 break; 5144 case UnaryOperator::LNot: // logical negation 5145 // Unlike +/-/~, integer promotions aren't done here (C99 6.5.3.3p5). 5146 DefaultFunctionArrayConversion(Input); 5147 resultType = Input->getType(); 5148 if (resultType->isDependentType()) 5149 break; 5150 if (!resultType->isScalarType()) // C99 6.5.3.3p1 5151 return ExprError(Diag(OpLoc, diag::err_typecheck_unary_expr) 5152 << resultType << Input->getSourceRange()); 5153 // LNot always has type int. C99 6.5.3.3p5. 5154 // In C++, it's bool. C++ 5.3.1p8 5155 resultType = getLangOptions().CPlusPlus ? Context.BoolTy : Context.IntTy; 5156 break; 5157 case UnaryOperator::Real: 5158 case UnaryOperator::Imag: 5159 resultType = CheckRealImagOperand(Input, OpLoc, Opc == UnaryOperator::Real); 5160 break; 5161 case UnaryOperator::Extension: 5162 resultType = Input->getType(); 5163 break; 5164 } 5165 if (resultType.isNull()) 5166 return ExprError(); 5167 5168 InputArg.release(); 5169 return Owned(new (Context) UnaryOperator(Input, Opc, resultType, OpLoc)); 5170} 5171 5172// Unary Operators. 'Tok' is the token for the operator. 5173Action::OwningExprResult Sema::ActOnUnaryOp(Scope *S, SourceLocation OpLoc, 5174 tok::TokenKind Op, ExprArg input) { 5175 Expr *Input = (Expr*)input.get(); 5176 UnaryOperator::Opcode Opc = ConvertTokenKindToUnaryOpcode(Op); 5177 5178 if (getLangOptions().CPlusPlus && Input->getType()->isOverloadableType()) { 5179 // Find all of the overloaded operators visible from this 5180 // point. We perform both an operator-name lookup from the local 5181 // scope and an argument-dependent lookup based on the types of 5182 // the arguments. 5183 FunctionSet Functions; 5184 OverloadedOperatorKind OverOp = UnaryOperator::getOverloadedOperator(Opc); 5185 if (OverOp != OO_None) { 5186 LookupOverloadedOperatorName(OverOp, S, Input->getType(), QualType(), 5187 Functions); 5188 DeclarationName OpName 5189 = Context.DeclarationNames.getCXXOperatorName(OverOp); 5190 ArgumentDependentLookup(OpName, &Input, 1, Functions); 5191 } 5192 5193 return CreateOverloadedUnaryOp(OpLoc, Opc, Functions, move(input)); 5194 } 5195 5196 return CreateBuiltinUnaryOp(OpLoc, Opc, move(input)); 5197} 5198 5199/// ActOnAddrLabel - Parse the GNU address of label extension: "&&foo". 5200Sema::OwningExprResult Sema::ActOnAddrLabel(SourceLocation OpLoc, 5201 SourceLocation LabLoc, 5202 IdentifierInfo *LabelII) { 5203 // Look up the record for this label identifier. 5204 LabelStmt *&LabelDecl = getLabelMap()[LabelII]; 5205 5206 // If we haven't seen this label yet, create a forward reference. It 5207 // will be validated and/or cleaned up in ActOnFinishFunctionBody. 5208 if (LabelDecl == 0) 5209 LabelDecl = new (Context) LabelStmt(LabLoc, LabelII, 0); 5210 5211 // Create the AST node. The address of a label always has type 'void*'. 5212 return Owned(new (Context) AddrLabelExpr(OpLoc, LabLoc, LabelDecl, 5213 Context.getPointerType(Context.VoidTy))); 5214} 5215 5216Sema::OwningExprResult 5217Sema::ActOnStmtExpr(SourceLocation LPLoc, StmtArg substmt, 5218 SourceLocation RPLoc) { // "({..})" 5219 Stmt *SubStmt = static_cast<Stmt*>(substmt.get()); 5220 assert(SubStmt && isa<CompoundStmt>(SubStmt) && "Invalid action invocation!"); 5221 CompoundStmt *Compound = cast<CompoundStmt>(SubStmt); 5222 5223 bool isFileScope = getCurFunctionOrMethodDecl() == 0; 5224 if (isFileScope) 5225 return ExprError(Diag(LPLoc, diag::err_stmtexpr_file_scope)); 5226 5227 // FIXME: there are a variety of strange constraints to enforce here, for 5228 // example, it is not possible to goto into a stmt expression apparently. 5229 // More semantic analysis is needed. 5230 5231 // If there are sub stmts in the compound stmt, take the type of the last one 5232 // as the type of the stmtexpr. 5233 QualType Ty = Context.VoidTy; 5234 5235 if (!Compound->body_empty()) { 5236 Stmt *LastStmt = Compound->body_back(); 5237 // If LastStmt is a label, skip down through into the body. 5238 while (LabelStmt *Label = dyn_cast<LabelStmt>(LastStmt)) 5239 LastStmt = Label->getSubStmt(); 5240 5241 if (Expr *LastExpr = dyn_cast<Expr>(LastStmt)) 5242 Ty = LastExpr->getType(); 5243 } 5244 5245 // FIXME: Check that expression type is complete/non-abstract; statement 5246 // expressions are not lvalues. 5247 5248 substmt.release(); 5249 return Owned(new (Context) StmtExpr(Compound, Ty, LPLoc, RPLoc)); 5250} 5251 5252Sema::OwningExprResult Sema::ActOnBuiltinOffsetOf(Scope *S, 5253 SourceLocation BuiltinLoc, 5254 SourceLocation TypeLoc, 5255 TypeTy *argty, 5256 OffsetOfComponent *CompPtr, 5257 unsigned NumComponents, 5258 SourceLocation RPLoc) { 5259 // FIXME: This function leaks all expressions in the offset components on 5260 // error. 5261 // FIXME: Preserve type source info. 5262 QualType ArgTy = GetTypeFromParser(argty); 5263 assert(!ArgTy.isNull() && "Missing type argument!"); 5264 5265 bool Dependent = ArgTy->isDependentType(); 5266 5267 // We must have at least one component that refers to the type, and the first 5268 // one is known to be a field designator. Verify that the ArgTy represents 5269 // a struct/union/class. 5270 if (!Dependent && !ArgTy->isRecordType()) 5271 return ExprError(Diag(TypeLoc, diag::err_offsetof_record_type) << ArgTy); 5272 5273 // FIXME: Type must be complete per C99 7.17p3 because a declaring a variable 5274 // with an incomplete type would be illegal. 5275 5276 // Otherwise, create a null pointer as the base, and iteratively process 5277 // the offsetof designators. 5278 QualType ArgTyPtr = Context.getPointerType(ArgTy); 5279 Expr* Res = new (Context) ImplicitValueInitExpr(ArgTyPtr); 5280 Res = new (Context) UnaryOperator(Res, UnaryOperator::Deref, 5281 ArgTy, SourceLocation()); 5282 5283 // offsetof with non-identifier designators (e.g. "offsetof(x, a.b[c])") are a 5284 // GCC extension, diagnose them. 5285 // FIXME: This diagnostic isn't actually visible because the location is in 5286 // a system header! 5287 if (NumComponents != 1) 5288 Diag(BuiltinLoc, diag::ext_offsetof_extended_field_designator) 5289 << SourceRange(CompPtr[1].LocStart, CompPtr[NumComponents-1].LocEnd); 5290 5291 if (!Dependent) { 5292 bool DidWarnAboutNonPOD = false; 5293 5294 // FIXME: Dependent case loses a lot of information here. And probably 5295 // leaks like a sieve. 5296 for (unsigned i = 0; i != NumComponents; ++i) { 5297 const OffsetOfComponent &OC = CompPtr[i]; 5298 if (OC.isBrackets) { 5299 // Offset of an array sub-field. TODO: Should we allow vector elements? 5300 const ArrayType *AT = Context.getAsArrayType(Res->getType()); 5301 if (!AT) { 5302 Res->Destroy(Context); 5303 return ExprError(Diag(OC.LocEnd, diag::err_offsetof_array_type) 5304 << Res->getType()); 5305 } 5306 5307 // FIXME: C++: Verify that operator[] isn't overloaded. 5308 5309 // Promote the array so it looks more like a normal array subscript 5310 // expression. 5311 DefaultFunctionArrayConversion(Res); 5312 5313 // C99 6.5.2.1p1 5314 Expr *Idx = static_cast<Expr*>(OC.U.E); 5315 // FIXME: Leaks Res 5316 if (!Idx->isTypeDependent() && !Idx->getType()->isIntegerType()) 5317 return ExprError(Diag(Idx->getLocStart(), 5318 diag::err_typecheck_subscript_not_integer) 5319 << Idx->getSourceRange()); 5320 5321 Res = new (Context) ArraySubscriptExpr(Res, Idx, AT->getElementType(), 5322 OC.LocEnd); 5323 continue; 5324 } 5325 5326 const RecordType *RC = Res->getType()->getAs<RecordType>(); 5327 if (!RC) { 5328 Res->Destroy(Context); 5329 return ExprError(Diag(OC.LocEnd, diag::err_offsetof_record_type) 5330 << Res->getType()); 5331 } 5332 5333 // Get the decl corresponding to this. 5334 RecordDecl *RD = RC->getDecl(); 5335 if (CXXRecordDecl *CRD = dyn_cast<CXXRecordDecl>(RD)) { 5336 if (!CRD->isPOD() && !DidWarnAboutNonPOD) { 5337 ExprError(Diag(BuiltinLoc, diag::warn_offsetof_non_pod_type) 5338 << SourceRange(CompPtr[0].LocStart, OC.LocEnd) 5339 << Res->getType()); 5340 DidWarnAboutNonPOD = true; 5341 } 5342 } 5343 5344 FieldDecl *MemberDecl 5345 = dyn_cast_or_null<FieldDecl>(LookupQualifiedName(RD, OC.U.IdentInfo, 5346 LookupMemberName) 5347 .getAsDecl()); 5348 // FIXME: Leaks Res 5349 if (!MemberDecl) 5350 return ExprError(Diag(BuiltinLoc, diag::err_typecheck_no_member) 5351 << OC.U.IdentInfo << SourceRange(OC.LocStart, OC.LocEnd)); 5352 5353 // FIXME: C++: Verify that MemberDecl isn't a static field. 5354 // FIXME: Verify that MemberDecl isn't a bitfield. 5355 if (cast<RecordDecl>(MemberDecl->getDeclContext())->isAnonymousStructOrUnion()) { 5356 Res = BuildAnonymousStructUnionMemberReference( 5357 SourceLocation(), MemberDecl, Res, SourceLocation()).takeAs<Expr>(); 5358 } else { 5359 // MemberDecl->getType() doesn't get the right qualifiers, but it 5360 // doesn't matter here. 5361 Res = new (Context) MemberExpr(Res, false, MemberDecl, OC.LocEnd, 5362 MemberDecl->getType().getNonReferenceType()); 5363 } 5364 } 5365 } 5366 5367 return Owned(new (Context) UnaryOperator(Res, UnaryOperator::OffsetOf, 5368 Context.getSizeType(), BuiltinLoc)); 5369} 5370 5371 5372Sema::OwningExprResult Sema::ActOnTypesCompatibleExpr(SourceLocation BuiltinLoc, 5373 TypeTy *arg1,TypeTy *arg2, 5374 SourceLocation RPLoc) { 5375 // FIXME: Preserve type source info. 5376 QualType argT1 = GetTypeFromParser(arg1); 5377 QualType argT2 = GetTypeFromParser(arg2); 5378 5379 assert((!argT1.isNull() && !argT2.isNull()) && "Missing type argument(s)"); 5380 5381 if (getLangOptions().CPlusPlus) { 5382 Diag(BuiltinLoc, diag::err_types_compatible_p_in_cplusplus) 5383 << SourceRange(BuiltinLoc, RPLoc); 5384 return ExprError(); 5385 } 5386 5387 return Owned(new (Context) TypesCompatibleExpr(Context.IntTy, BuiltinLoc, 5388 argT1, argT2, RPLoc)); 5389} 5390 5391Sema::OwningExprResult Sema::ActOnChooseExpr(SourceLocation BuiltinLoc, 5392 ExprArg cond, 5393 ExprArg expr1, ExprArg expr2, 5394 SourceLocation RPLoc) { 5395 Expr *CondExpr = static_cast<Expr*>(cond.get()); 5396 Expr *LHSExpr = static_cast<Expr*>(expr1.get()); 5397 Expr *RHSExpr = static_cast<Expr*>(expr2.get()); 5398 5399 assert((CondExpr && LHSExpr && RHSExpr) && "Missing type argument(s)"); 5400 5401 QualType resType; 5402 if (CondExpr->isTypeDependent() || CondExpr->isValueDependent()) { 5403 resType = Context.DependentTy; 5404 } else { 5405 // The conditional expression is required to be a constant expression. 5406 llvm::APSInt condEval(32); 5407 SourceLocation ExpLoc; 5408 if (!CondExpr->isIntegerConstantExpr(condEval, Context, &ExpLoc)) 5409 return ExprError(Diag(ExpLoc, 5410 diag::err_typecheck_choose_expr_requires_constant) 5411 << CondExpr->getSourceRange()); 5412 5413 // If the condition is > zero, then the AST type is the same as the LSHExpr. 5414 resType = condEval.getZExtValue() ? LHSExpr->getType() : RHSExpr->getType(); 5415 } 5416 5417 cond.release(); expr1.release(); expr2.release(); 5418 return Owned(new (Context) ChooseExpr(BuiltinLoc, CondExpr, LHSExpr, RHSExpr, 5419 resType, RPLoc)); 5420} 5421 5422//===----------------------------------------------------------------------===// 5423// Clang Extensions. 5424//===----------------------------------------------------------------------===// 5425 5426/// ActOnBlockStart - This callback is invoked when a block literal is started. 5427void Sema::ActOnBlockStart(SourceLocation CaretLoc, Scope *BlockScope) { 5428 // Analyze block parameters. 5429 BlockSemaInfo *BSI = new BlockSemaInfo(); 5430 5431 // Add BSI to CurBlock. 5432 BSI->PrevBlockInfo = CurBlock; 5433 CurBlock = BSI; 5434 5435 BSI->ReturnType = QualType(); 5436 BSI->TheScope = BlockScope; 5437 BSI->hasBlockDeclRefExprs = false; 5438 BSI->hasPrototype = false; 5439 BSI->SavedFunctionNeedsScopeChecking = CurFunctionNeedsScopeChecking; 5440 CurFunctionNeedsScopeChecking = false; 5441 5442 BSI->TheDecl = BlockDecl::Create(Context, CurContext, CaretLoc); 5443 PushDeclContext(BlockScope, BSI->TheDecl); 5444} 5445 5446void Sema::ActOnBlockArguments(Declarator &ParamInfo, Scope *CurScope) { 5447 assert(ParamInfo.getIdentifier()==0 && "block-id should have no identifier!"); 5448 5449 if (ParamInfo.getNumTypeObjects() == 0 5450 || ParamInfo.getTypeObject(0).Kind != DeclaratorChunk::Function) { 5451 ProcessDeclAttributes(CurScope, CurBlock->TheDecl, ParamInfo); 5452 QualType T = GetTypeForDeclarator(ParamInfo, CurScope); 5453 5454 if (T->isArrayType()) { 5455 Diag(ParamInfo.getSourceRange().getBegin(), 5456 diag::err_block_returns_array); 5457 return; 5458 } 5459 5460 // The parameter list is optional, if there was none, assume (). 5461 if (!T->isFunctionType()) 5462 T = Context.getFunctionType(T, NULL, 0, 0, 0); 5463 5464 CurBlock->hasPrototype = true; 5465 CurBlock->isVariadic = false; 5466 // Check for a valid sentinel attribute on this block. 5467 if (CurBlock->TheDecl->getAttr<SentinelAttr>()) { 5468 Diag(ParamInfo.getAttributes()->getLoc(), 5469 diag::warn_attribute_sentinel_not_variadic) << 1; 5470 // FIXME: remove the attribute. 5471 } 5472 QualType RetTy = T.getTypePtr()->getAsFunctionType()->getResultType(); 5473 5474 // Do not allow returning a objc interface by-value. 5475 if (RetTy->isObjCInterfaceType()) { 5476 Diag(ParamInfo.getSourceRange().getBegin(), 5477 diag::err_object_cannot_be_passed_returned_by_value) << 0 << RetTy; 5478 return; 5479 } 5480 return; 5481 } 5482 5483 // Analyze arguments to block. 5484 assert(ParamInfo.getTypeObject(0).Kind == DeclaratorChunk::Function && 5485 "Not a function declarator!"); 5486 DeclaratorChunk::FunctionTypeInfo &FTI = ParamInfo.getTypeObject(0).Fun; 5487 5488 CurBlock->hasPrototype = FTI.hasPrototype; 5489 CurBlock->isVariadic = true; 5490 5491 // Check for C99 6.7.5.3p10 - foo(void) is a non-varargs function that takes 5492 // no arguments, not a function that takes a single void argument. 5493 if (FTI.hasPrototype && 5494 FTI.NumArgs == 1 && !FTI.isVariadic && FTI.ArgInfo[0].Ident == 0 && 5495 (!FTI.ArgInfo[0].Param.getAs<ParmVarDecl>()->getType().getCVRQualifiers()&& 5496 FTI.ArgInfo[0].Param.getAs<ParmVarDecl>()->getType()->isVoidType())) { 5497 // empty arg list, don't push any params. 5498 CurBlock->isVariadic = false; 5499 } else if (FTI.hasPrototype) { 5500 for (unsigned i = 0, e = FTI.NumArgs; i != e; ++i) 5501 CurBlock->Params.push_back(FTI.ArgInfo[i].Param.getAs<ParmVarDecl>()); 5502 CurBlock->isVariadic = FTI.isVariadic; 5503 } 5504 CurBlock->TheDecl->setParams(Context, CurBlock->Params.data(), 5505 CurBlock->Params.size()); 5506 CurBlock->TheDecl->setIsVariadic(CurBlock->isVariadic); 5507 ProcessDeclAttributes(CurScope, CurBlock->TheDecl, ParamInfo); 5508 for (BlockDecl::param_iterator AI = CurBlock->TheDecl->param_begin(), 5509 E = CurBlock->TheDecl->param_end(); AI != E; ++AI) 5510 // If this has an identifier, add it to the scope stack. 5511 if ((*AI)->getIdentifier()) 5512 PushOnScopeChains(*AI, CurBlock->TheScope); 5513 5514 // Check for a valid sentinel attribute on this block. 5515 if (!CurBlock->isVariadic && 5516 CurBlock->TheDecl->getAttr<SentinelAttr>()) { 5517 Diag(ParamInfo.getAttributes()->getLoc(), 5518 diag::warn_attribute_sentinel_not_variadic) << 1; 5519 // FIXME: remove the attribute. 5520 } 5521 5522 // Analyze the return type. 5523 QualType T = GetTypeForDeclarator(ParamInfo, CurScope); 5524 QualType RetTy = T->getAsFunctionType()->getResultType(); 5525 5526 // Do not allow returning a objc interface by-value. 5527 if (RetTy->isObjCInterfaceType()) { 5528 Diag(ParamInfo.getSourceRange().getBegin(), 5529 diag::err_object_cannot_be_passed_returned_by_value) << 0 << RetTy; 5530 } else if (!RetTy->isDependentType()) 5531 CurBlock->ReturnType = RetTy; 5532} 5533 5534/// ActOnBlockError - If there is an error parsing a block, this callback 5535/// is invoked to pop the information about the block from the action impl. 5536void Sema::ActOnBlockError(SourceLocation CaretLoc, Scope *CurScope) { 5537 // Ensure that CurBlock is deleted. 5538 llvm::OwningPtr<BlockSemaInfo> CC(CurBlock); 5539 5540 CurFunctionNeedsScopeChecking = CurBlock->SavedFunctionNeedsScopeChecking; 5541 5542 // Pop off CurBlock, handle nested blocks. 5543 PopDeclContext(); 5544 CurBlock = CurBlock->PrevBlockInfo; 5545 // FIXME: Delete the ParmVarDecl objects as well??? 5546} 5547 5548/// ActOnBlockStmtExpr - This is called when the body of a block statement 5549/// literal was successfully completed. ^(int x){...} 5550Sema::OwningExprResult Sema::ActOnBlockStmtExpr(SourceLocation CaretLoc, 5551 StmtArg body, Scope *CurScope) { 5552 // If blocks are disabled, emit an error. 5553 if (!LangOpts.Blocks) 5554 Diag(CaretLoc, diag::err_blocks_disable); 5555 5556 // Ensure that CurBlock is deleted. 5557 llvm::OwningPtr<BlockSemaInfo> BSI(CurBlock); 5558 5559 PopDeclContext(); 5560 5561 // Pop off CurBlock, handle nested blocks. 5562 CurBlock = CurBlock->PrevBlockInfo; 5563 5564 QualType RetTy = Context.VoidTy; 5565 if (!BSI->ReturnType.isNull()) 5566 RetTy = BSI->ReturnType; 5567 5568 llvm::SmallVector<QualType, 8> ArgTypes; 5569 for (unsigned i = 0, e = BSI->Params.size(); i != e; ++i) 5570 ArgTypes.push_back(BSI->Params[i]->getType()); 5571 5572 bool NoReturn = BSI->TheDecl->getAttr<NoReturnAttr>(); 5573 QualType BlockTy; 5574 if (!BSI->hasPrototype) 5575 BlockTy = Context.getFunctionType(RetTy, 0, 0, false, 0, false, false, 0, 0, 5576 NoReturn); 5577 else 5578 BlockTy = Context.getFunctionType(RetTy, ArgTypes.data(), ArgTypes.size(), 5579 BSI->isVariadic, 0, false, false, 0, 0, 5580 NoReturn); 5581 5582 // FIXME: Check that return/parameter types are complete/non-abstract 5583 DiagnoseUnusedParameters(BSI->Params.begin(), BSI->Params.end()); 5584 BlockTy = Context.getBlockPointerType(BlockTy); 5585 5586 // If needed, diagnose invalid gotos and switches in the block. 5587 if (CurFunctionNeedsScopeChecking) 5588 DiagnoseInvalidJumps(static_cast<CompoundStmt*>(body.get())); 5589 CurFunctionNeedsScopeChecking = BSI->SavedFunctionNeedsScopeChecking; 5590 5591 BSI->TheDecl->setBody(body.takeAs<CompoundStmt>()); 5592 CheckFallThroughForBlock(BlockTy, BSI->TheDecl->getBody()); 5593 return Owned(new (Context) BlockExpr(BSI->TheDecl, BlockTy, 5594 BSI->hasBlockDeclRefExprs)); 5595} 5596 5597Sema::OwningExprResult Sema::ActOnVAArg(SourceLocation BuiltinLoc, 5598 ExprArg expr, TypeTy *type, 5599 SourceLocation RPLoc) { 5600 QualType T = GetTypeFromParser(type); 5601 Expr *E = static_cast<Expr*>(expr.get()); 5602 Expr *OrigExpr = E; 5603 5604 InitBuiltinVaListType(); 5605 5606 // Get the va_list type 5607 QualType VaListType = Context.getBuiltinVaListType(); 5608 if (VaListType->isArrayType()) { 5609 // Deal with implicit array decay; for example, on x86-64, 5610 // va_list is an array, but it's supposed to decay to 5611 // a pointer for va_arg. 5612 VaListType = Context.getArrayDecayedType(VaListType); 5613 // Make sure the input expression also decays appropriately. 5614 UsualUnaryConversions(E); 5615 } else { 5616 // Otherwise, the va_list argument must be an l-value because 5617 // it is modified by va_arg. 5618 if (!E->isTypeDependent() && 5619 CheckForModifiableLvalue(E, BuiltinLoc, *this)) 5620 return ExprError(); 5621 } 5622 5623 if (!E->isTypeDependent() && 5624 !Context.hasSameType(VaListType, E->getType())) { 5625 return ExprError(Diag(E->getLocStart(), 5626 diag::err_first_argument_to_va_arg_not_of_type_va_list) 5627 << OrigExpr->getType() << E->getSourceRange()); 5628 } 5629 5630 // FIXME: Check that type is complete/non-abstract 5631 // FIXME: Warn if a non-POD type is passed in. 5632 5633 expr.release(); 5634 return Owned(new (Context) VAArgExpr(BuiltinLoc, E, T.getNonReferenceType(), 5635 RPLoc)); 5636} 5637 5638Sema::OwningExprResult Sema::ActOnGNUNullExpr(SourceLocation TokenLoc) { 5639 // The type of __null will be int or long, depending on the size of 5640 // pointers on the target. 5641 QualType Ty; 5642 if (Context.Target.getPointerWidth(0) == Context.Target.getIntWidth()) 5643 Ty = Context.IntTy; 5644 else 5645 Ty = Context.LongTy; 5646 5647 return Owned(new (Context) GNUNullExpr(Ty, TokenLoc)); 5648} 5649 5650bool Sema::DiagnoseAssignmentResult(AssignConvertType ConvTy, 5651 SourceLocation Loc, 5652 QualType DstType, QualType SrcType, 5653 Expr *SrcExpr, const char *Flavor) { 5654 // Decode the result (notice that AST's are still created for extensions). 5655 bool isInvalid = false; 5656 unsigned DiagKind; 5657 switch (ConvTy) { 5658 default: assert(0 && "Unknown conversion type"); 5659 case Compatible: return false; 5660 case PointerToInt: 5661 DiagKind = diag::ext_typecheck_convert_pointer_int; 5662 break; 5663 case IntToPointer: 5664 DiagKind = diag::ext_typecheck_convert_int_pointer; 5665 break; 5666 case IncompatiblePointer: 5667 DiagKind = diag::ext_typecheck_convert_incompatible_pointer; 5668 break; 5669 case IncompatiblePointerSign: 5670 DiagKind = diag::ext_typecheck_convert_incompatible_pointer_sign; 5671 break; 5672 case FunctionVoidPointer: 5673 DiagKind = diag::ext_typecheck_convert_pointer_void_func; 5674 break; 5675 case CompatiblePointerDiscardsQualifiers: 5676 // If the qualifiers lost were because we were applying the 5677 // (deprecated) C++ conversion from a string literal to a char* 5678 // (or wchar_t*), then there was no error (C++ 4.2p2). FIXME: 5679 // Ideally, this check would be performed in 5680 // CheckPointerTypesForAssignment. However, that would require a 5681 // bit of refactoring (so that the second argument is an 5682 // expression, rather than a type), which should be done as part 5683 // of a larger effort to fix CheckPointerTypesForAssignment for 5684 // C++ semantics. 5685 if (getLangOptions().CPlusPlus && 5686 IsStringLiteralToNonConstPointerConversion(SrcExpr, DstType)) 5687 return false; 5688 DiagKind = diag::ext_typecheck_convert_discards_qualifiers; 5689 break; 5690 case IntToBlockPointer: 5691 DiagKind = diag::err_int_to_block_pointer; 5692 break; 5693 case IncompatibleBlockPointer: 5694 DiagKind = diag::err_typecheck_convert_incompatible_block_pointer; 5695 break; 5696 case IncompatibleObjCQualifiedId: 5697 // FIXME: Diagnose the problem in ObjCQualifiedIdTypesAreCompatible, since 5698 // it can give a more specific diagnostic. 5699 DiagKind = diag::warn_incompatible_qualified_id; 5700 break; 5701 case IncompatibleVectors: 5702 DiagKind = diag::warn_incompatible_vectors; 5703 break; 5704 case Incompatible: 5705 DiagKind = diag::err_typecheck_convert_incompatible; 5706 isInvalid = true; 5707 break; 5708 } 5709 5710 Diag(Loc, DiagKind) << DstType << SrcType << Flavor 5711 << SrcExpr->getSourceRange(); 5712 return isInvalid; 5713} 5714 5715bool Sema::VerifyIntegerConstantExpression(const Expr *E, llvm::APSInt *Result){ 5716 llvm::APSInt ICEResult; 5717 if (E->isIntegerConstantExpr(ICEResult, Context)) { 5718 if (Result) 5719 *Result = ICEResult; 5720 return false; 5721 } 5722 5723 Expr::EvalResult EvalResult; 5724 5725 if (!E->Evaluate(EvalResult, Context) || !EvalResult.Val.isInt() || 5726 EvalResult.HasSideEffects) { 5727 Diag(E->getExprLoc(), diag::err_expr_not_ice) << E->getSourceRange(); 5728 5729 if (EvalResult.Diag) { 5730 // We only show the note if it's not the usual "invalid subexpression" 5731 // or if it's actually in a subexpression. 5732 if (EvalResult.Diag != diag::note_invalid_subexpr_in_ice || 5733 E->IgnoreParens() != EvalResult.DiagExpr->IgnoreParens()) 5734 Diag(EvalResult.DiagLoc, EvalResult.Diag); 5735 } 5736 5737 return true; 5738 } 5739 5740 Diag(E->getExprLoc(), diag::ext_expr_not_ice) << 5741 E->getSourceRange(); 5742 5743 if (EvalResult.Diag && 5744 Diags.getDiagnosticLevel(diag::ext_expr_not_ice) != Diagnostic::Ignored) 5745 Diag(EvalResult.DiagLoc, EvalResult.Diag); 5746 5747 if (Result) 5748 *Result = EvalResult.Val.getInt(); 5749 return false; 5750} 5751 5752Sema::ExpressionEvaluationContext 5753Sema::PushExpressionEvaluationContext(ExpressionEvaluationContext NewContext) { 5754 // Introduce a new set of potentially referenced declarations to the stack. 5755 if (NewContext == PotentiallyPotentiallyEvaluated) 5756 PotentiallyReferencedDeclStack.push_back(PotentiallyReferencedDecls()); 5757 5758 std::swap(ExprEvalContext, NewContext); 5759 return NewContext; 5760} 5761 5762void 5763Sema::PopExpressionEvaluationContext(ExpressionEvaluationContext OldContext, 5764 ExpressionEvaluationContext NewContext) { 5765 ExprEvalContext = NewContext; 5766 5767 if (OldContext == PotentiallyPotentiallyEvaluated) { 5768 // Mark any remaining declarations in the current position of the stack 5769 // as "referenced". If they were not meant to be referenced, semantic 5770 // analysis would have eliminated them (e.g., in ActOnCXXTypeId). 5771 PotentiallyReferencedDecls RemainingDecls; 5772 RemainingDecls.swap(PotentiallyReferencedDeclStack.back()); 5773 PotentiallyReferencedDeclStack.pop_back(); 5774 5775 for (PotentiallyReferencedDecls::iterator I = RemainingDecls.begin(), 5776 IEnd = RemainingDecls.end(); 5777 I != IEnd; ++I) 5778 MarkDeclarationReferenced(I->first, I->second); 5779 } 5780} 5781 5782/// \brief Note that the given declaration was referenced in the source code. 5783/// 5784/// This routine should be invoke whenever a given declaration is referenced 5785/// in the source code, and where that reference occurred. If this declaration 5786/// reference means that the the declaration is used (C++ [basic.def.odr]p2, 5787/// C99 6.9p3), then the declaration will be marked as used. 5788/// 5789/// \param Loc the location where the declaration was referenced. 5790/// 5791/// \param D the declaration that has been referenced by the source code. 5792void Sema::MarkDeclarationReferenced(SourceLocation Loc, Decl *D) { 5793 assert(D && "No declaration?"); 5794 5795 if (D->isUsed()) 5796 return; 5797 5798 // Mark a parameter declaration "used", regardless of whether we're in a 5799 // template or not. 5800 if (isa<ParmVarDecl>(D)) 5801 D->setUsed(true); 5802 5803 // Do not mark anything as "used" within a dependent context; wait for 5804 // an instantiation. 5805 if (CurContext->isDependentContext()) 5806 return; 5807 5808 switch (ExprEvalContext) { 5809 case Unevaluated: 5810 // We are in an expression that is not potentially evaluated; do nothing. 5811 return; 5812 5813 case PotentiallyEvaluated: 5814 // We are in a potentially-evaluated expression, so this declaration is 5815 // "used"; handle this below. 5816 break; 5817 5818 case PotentiallyPotentiallyEvaluated: 5819 // We are in an expression that may be potentially evaluated; queue this 5820 // declaration reference until we know whether the expression is 5821 // potentially evaluated. 5822 PotentiallyReferencedDeclStack.back().push_back(std::make_pair(Loc, D)); 5823 return; 5824 } 5825 5826 // Note that this declaration has been used. 5827 if (CXXConstructorDecl *Constructor = dyn_cast<CXXConstructorDecl>(D)) { 5828 unsigned TypeQuals; 5829 if (Constructor->isImplicit() && Constructor->isDefaultConstructor()) { 5830 if (!Constructor->isUsed()) 5831 DefineImplicitDefaultConstructor(Loc, Constructor); 5832 } else if (Constructor->isImplicit() && 5833 Constructor->isCopyConstructor(Context, TypeQuals)) { 5834 if (!Constructor->isUsed()) 5835 DefineImplicitCopyConstructor(Loc, Constructor, TypeQuals); 5836 } 5837 } else if (CXXDestructorDecl *Destructor = dyn_cast<CXXDestructorDecl>(D)) { 5838 if (Destructor->isImplicit() && !Destructor->isUsed()) 5839 DefineImplicitDestructor(Loc, Destructor); 5840 5841 } else if (CXXMethodDecl *MethodDecl = dyn_cast<CXXMethodDecl>(D)) { 5842 if (MethodDecl->isImplicit() && MethodDecl->isOverloadedOperator() && 5843 MethodDecl->getOverloadedOperator() == OO_Equal) { 5844 if (!MethodDecl->isUsed()) 5845 DefineImplicitOverloadedAssign(Loc, MethodDecl); 5846 } 5847 } 5848 if (FunctionDecl *Function = dyn_cast<FunctionDecl>(D)) { 5849 // Implicit instantiation of function templates and member functions of 5850 // class templates. 5851 if (!Function->getBody()) { 5852 // FIXME: distinguish between implicit instantiations of function 5853 // templates and explicit specializations (the latter don't get 5854 // instantiated, naturally). 5855 if (Function->getInstantiatedFromMemberFunction() || 5856 Function->getPrimaryTemplate()) 5857 PendingImplicitInstantiations.push_back(std::make_pair(Function, Loc)); 5858 } 5859 5860 5861 // FIXME: keep track of references to static functions 5862 Function->setUsed(true); 5863 return; 5864 } 5865 5866 if (VarDecl *Var = dyn_cast<VarDecl>(D)) { 5867 // Implicit instantiation of static data members of class templates. 5868 // FIXME: distinguish between implicit instantiations (which we need to 5869 // actually instantiate) and explicit specializations. 5870 if (Var->isStaticDataMember() && 5871 Var->getInstantiatedFromStaticDataMember()) 5872 PendingImplicitInstantiations.push_back(std::make_pair(Var, Loc)); 5873 5874 // FIXME: keep track of references to static data? 5875 5876 D->setUsed(true); 5877 return; 5878} 5879} 5880 5881