SemaExpr.cpp revision 253fc4d146d4815c9a4ef15a7196edb2e7831865
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/// \brief Determine whether the use of this declaration is valid, and 30/// emit any corresponding diagnostics. 31/// 32/// This routine diagnoses various problems with referencing 33/// declarations that can occur when using a declaration. For example, 34/// it might warn if a deprecated or unavailable declaration is being 35/// used, or produce an error (and return true) if a C++0x deleted 36/// function is being used. 37/// 38/// \returns true if there was an error (this declaration cannot be 39/// referenced), false otherwise. 40bool Sema::DiagnoseUseOfDecl(NamedDecl *D, SourceLocation Loc) { 41 // See if the decl is deprecated. 42 if (D->getAttr<DeprecatedAttr>()) { 43 // Implementing deprecated stuff requires referencing deprecated 44 // stuff. Don't warn if we are implementing a deprecated 45 // construct. 46 bool isSilenced = false; 47 48 if (NamedDecl *ND = getCurFunctionOrMethodDecl()) { 49 // If this reference happens *in* a deprecated function or method, don't 50 // warn. 51 isSilenced = ND->getAttr<DeprecatedAttr>(); 52 53 // If this is an Objective-C method implementation, check to see if the 54 // method was deprecated on the declaration, not the definition. 55 if (ObjCMethodDecl *MD = dyn_cast<ObjCMethodDecl>(ND)) { 56 // The semantic decl context of a ObjCMethodDecl is the 57 // ObjCImplementationDecl. 58 if (ObjCImplementationDecl *Impl 59 = dyn_cast<ObjCImplementationDecl>(MD->getParent())) { 60 61 MD = Impl->getClassInterface()->getMethod(MD->getSelector(), 62 MD->isInstanceMethod()); 63 isSilenced |= MD && MD->getAttr<DeprecatedAttr>(); 64 } 65 } 66 } 67 68 if (!isSilenced) 69 Diag(Loc, diag::warn_deprecated) << D->getDeclName(); 70 } 71 72 // See if this is a deleted function. 73 if (FunctionDecl *FD = dyn_cast<FunctionDecl>(D)) { 74 if (FD->isDeleted()) { 75 Diag(Loc, diag::err_deleted_function_use); 76 Diag(D->getLocation(), diag::note_unavailable_here) << true; 77 return true; 78 } 79 } 80 81 // See if the decl is unavailable 82 if (D->getAttr<UnavailableAttr>()) { 83 Diag(Loc, diag::warn_unavailable) << D->getDeclName(); 84 Diag(D->getLocation(), diag::note_unavailable_here) << 0; 85 } 86 87 return false; 88} 89 90SourceRange Sema::getExprRange(ExprTy *E) const { 91 Expr *Ex = (Expr *)E; 92 return Ex? Ex->getSourceRange() : SourceRange(); 93} 94 95//===----------------------------------------------------------------------===// 96// Standard Promotions and Conversions 97//===----------------------------------------------------------------------===// 98 99/// DefaultFunctionArrayConversion (C99 6.3.2.1p3, C99 6.3.2.1p4). 100void Sema::DefaultFunctionArrayConversion(Expr *&E) { 101 QualType Ty = E->getType(); 102 assert(!Ty.isNull() && "DefaultFunctionArrayConversion - missing type"); 103 104 if (Ty->isFunctionType()) 105 ImpCastExprToType(E, Context.getPointerType(Ty)); 106 else if (Ty->isArrayType()) { 107 // In C90 mode, arrays only promote to pointers if the array expression is 108 // an lvalue. The relevant legalese is C90 6.2.2.1p3: "an lvalue that has 109 // type 'array of type' is converted to an expression that has type 'pointer 110 // to type'...". In C99 this was changed to: C99 6.3.2.1p3: "an expression 111 // that has type 'array of type' ...". The relevant change is "an lvalue" 112 // (C90) to "an expression" (C99). 113 // 114 // C++ 4.2p1: 115 // An lvalue or rvalue of type "array of N T" or "array of unknown bound of 116 // T" can be converted to an rvalue of type "pointer to T". 117 // 118 if (getLangOptions().C99 || getLangOptions().CPlusPlus || 119 E->isLvalue(Context) == Expr::LV_Valid) 120 ImpCastExprToType(E, Context.getArrayDecayedType(Ty)); 121 } 122} 123 124/// UsualUnaryConversions - Performs various conversions that are common to most 125/// operators (C99 6.3). The conversions of array and function types are 126/// sometimes surpressed. For example, the array->pointer conversion doesn't 127/// apply if the array is an argument to the sizeof or address (&) operators. 128/// In these instances, this routine should *not* be called. 129Expr *Sema::UsualUnaryConversions(Expr *&Expr) { 130 QualType Ty = Expr->getType(); 131 assert(!Ty.isNull() && "UsualUnaryConversions - missing type"); 132 133 if (Ty->isPromotableIntegerType()) // C99 6.3.1.1p2 134 ImpCastExprToType(Expr, Context.IntTy); 135 else 136 DefaultFunctionArrayConversion(Expr); 137 138 return Expr; 139} 140 141/// DefaultArgumentPromotion (C99 6.5.2.2p6). Used for function calls that 142/// do not have a prototype. Arguments that have type float are promoted to 143/// double. All other argument types are converted by UsualUnaryConversions(). 144void Sema::DefaultArgumentPromotion(Expr *&Expr) { 145 QualType Ty = Expr->getType(); 146 assert(!Ty.isNull() && "DefaultArgumentPromotion - missing type"); 147 148 // If this is a 'float' (CVR qualified or typedef) promote to double. 149 if (const BuiltinType *BT = Ty->getAsBuiltinType()) 150 if (BT->getKind() == BuiltinType::Float) 151 return ImpCastExprToType(Expr, Context.DoubleTy); 152 153 UsualUnaryConversions(Expr); 154} 155 156// DefaultVariadicArgumentPromotion - Like DefaultArgumentPromotion, but 157// will warn if the resulting type is not a POD type. 158void Sema::DefaultVariadicArgumentPromotion(Expr *&Expr, VariadicCallType CT) { 159 DefaultArgumentPromotion(Expr); 160 161 if (!Expr->getType()->isPODType()) { 162 Diag(Expr->getLocStart(), 163 diag::warn_cannot_pass_non_pod_arg_to_vararg) << 164 Expr->getType() << CT; 165 } 166} 167 168 169/// UsualArithmeticConversions - Performs various conversions that are common to 170/// binary operators (C99 6.3.1.8). If both operands aren't arithmetic, this 171/// routine returns the first non-arithmetic type found. The client is 172/// responsible for emitting appropriate error diagnostics. 173/// FIXME: verify the conversion rules for "complex int" are consistent with 174/// GCC. 175QualType Sema::UsualArithmeticConversions(Expr *&lhsExpr, Expr *&rhsExpr, 176 bool isCompAssign) { 177 if (!isCompAssign) { 178 UsualUnaryConversions(lhsExpr); 179 UsualUnaryConversions(rhsExpr); 180 } 181 182 // For conversion purposes, we ignore any qualifiers. 183 // For example, "const float" and "float" are equivalent. 184 QualType lhs = 185 Context.getCanonicalType(lhsExpr->getType()).getUnqualifiedType(); 186 QualType rhs = 187 Context.getCanonicalType(rhsExpr->getType()).getUnqualifiedType(); 188 189 // If both types are identical, no conversion is needed. 190 if (lhs == rhs) 191 return lhs; 192 193 // If either side is a non-arithmetic type (e.g. a pointer), we are done. 194 // The caller can deal with this (e.g. pointer + int). 195 if (!lhs->isArithmeticType() || !rhs->isArithmeticType()) 196 return lhs; 197 198 QualType destType = UsualArithmeticConversionsType(lhs, rhs); 199 if (!isCompAssign) { 200 ImpCastExprToType(lhsExpr, destType); 201 ImpCastExprToType(rhsExpr, destType); 202 } 203 return destType; 204} 205 206QualType Sema::UsualArithmeticConversionsType(QualType lhs, QualType rhs) { 207 // Perform the usual unary conversions. We do this early so that 208 // integral promotions to "int" can allow us to exit early, in the 209 // lhs == rhs check. Also, for conversion purposes, we ignore any 210 // qualifiers. For example, "const float" and "float" are 211 // equivalent. 212 if (lhs->isPromotableIntegerType()) 213 lhs = Context.IntTy; 214 else 215 lhs = lhs.getUnqualifiedType(); 216 if (rhs->isPromotableIntegerType()) 217 rhs = Context.IntTy; 218 else 219 rhs = rhs.getUnqualifiedType(); 220 221 // If both types are identical, no conversion is needed. 222 if (lhs == rhs) 223 return lhs; 224 225 // If either side is a non-arithmetic type (e.g. a pointer), we are done. 226 // The caller can deal with this (e.g. pointer + int). 227 if (!lhs->isArithmeticType() || !rhs->isArithmeticType()) 228 return lhs; 229 230 // At this point, we have two different arithmetic types. 231 232 // Handle complex types first (C99 6.3.1.8p1). 233 if (lhs->isComplexType() || rhs->isComplexType()) { 234 // if we have an integer operand, the result is the complex type. 235 if (rhs->isIntegerType() || rhs->isComplexIntegerType()) { 236 // convert the rhs to the lhs complex type. 237 return lhs; 238 } 239 if (lhs->isIntegerType() || lhs->isComplexIntegerType()) { 240 // convert the lhs to the rhs complex type. 241 return rhs; 242 } 243 // This handles complex/complex, complex/float, or float/complex. 244 // When both operands are complex, the shorter operand is converted to the 245 // type of the longer, and that is the type of the result. This corresponds 246 // to what is done when combining two real floating-point operands. 247 // The fun begins when size promotion occur across type domains. 248 // From H&S 6.3.4: When one operand is complex and the other is a real 249 // floating-point type, the less precise type is converted, within it's 250 // real or complex domain, to the precision of the other type. For example, 251 // when combining a "long double" with a "double _Complex", the 252 // "double _Complex" is promoted to "long double _Complex". 253 int result = Context.getFloatingTypeOrder(lhs, rhs); 254 255 if (result > 0) { // The left side is bigger, convert rhs. 256 rhs = Context.getFloatingTypeOfSizeWithinDomain(lhs, rhs); 257 } else if (result < 0) { // The right side is bigger, convert lhs. 258 lhs = Context.getFloatingTypeOfSizeWithinDomain(rhs, lhs); 259 } 260 // At this point, lhs and rhs have the same rank/size. Now, make sure the 261 // domains match. This is a requirement for our implementation, C99 262 // does not require this promotion. 263 if (lhs != rhs) { // Domains don't match, we have complex/float mix. 264 if (lhs->isRealFloatingType()) { // handle "double, _Complex double". 265 return rhs; 266 } else { // handle "_Complex double, double". 267 return lhs; 268 } 269 } 270 return lhs; // The domain/size match exactly. 271 } 272 // Now handle "real" floating types (i.e. float, double, long double). 273 if (lhs->isRealFloatingType() || rhs->isRealFloatingType()) { 274 // if we have an integer operand, the result is the real floating type. 275 if (rhs->isIntegerType()) { 276 // convert rhs to the lhs floating point type. 277 return lhs; 278 } 279 if (rhs->isComplexIntegerType()) { 280 // convert rhs to the complex floating point type. 281 return Context.getComplexType(lhs); 282 } 283 if (lhs->isIntegerType()) { 284 // convert lhs to the rhs floating point type. 285 return rhs; 286 } 287 if (lhs->isComplexIntegerType()) { 288 // convert lhs to the complex floating point type. 289 return Context.getComplexType(rhs); 290 } 291 // We have two real floating types, float/complex combos were handled above. 292 // Convert the smaller operand to the bigger result. 293 int result = Context.getFloatingTypeOrder(lhs, rhs); 294 if (result > 0) // convert the rhs 295 return lhs; 296 assert(result < 0 && "illegal float comparison"); 297 return rhs; // convert the lhs 298 } 299 if (lhs->isComplexIntegerType() || rhs->isComplexIntegerType()) { 300 // Handle GCC complex int extension. 301 const ComplexType *lhsComplexInt = lhs->getAsComplexIntegerType(); 302 const ComplexType *rhsComplexInt = rhs->getAsComplexIntegerType(); 303 304 if (lhsComplexInt && rhsComplexInt) { 305 if (Context.getIntegerTypeOrder(lhsComplexInt->getElementType(), 306 rhsComplexInt->getElementType()) >= 0) 307 return lhs; // convert the rhs 308 return rhs; 309 } else if (lhsComplexInt && rhs->isIntegerType()) { 310 // convert the rhs to the lhs complex type. 311 return lhs; 312 } else if (rhsComplexInt && lhs->isIntegerType()) { 313 // convert the lhs to the rhs complex type. 314 return rhs; 315 } 316 } 317 // Finally, we have two differing integer types. 318 // The rules for this case are in C99 6.3.1.8 319 int compare = Context.getIntegerTypeOrder(lhs, rhs); 320 bool lhsSigned = lhs->isSignedIntegerType(), 321 rhsSigned = rhs->isSignedIntegerType(); 322 QualType destType; 323 if (lhsSigned == rhsSigned) { 324 // Same signedness; use the higher-ranked type 325 destType = compare >= 0 ? lhs : rhs; 326 } else if (compare != (lhsSigned ? 1 : -1)) { 327 // The unsigned type has greater than or equal rank to the 328 // signed type, so use the unsigned type 329 destType = lhsSigned ? rhs : lhs; 330 } else if (Context.getIntWidth(lhs) != Context.getIntWidth(rhs)) { 331 // The two types are different widths; if we are here, that 332 // means the signed type is larger than the unsigned type, so 333 // use the signed type. 334 destType = lhsSigned ? lhs : rhs; 335 } else { 336 // The signed type is higher-ranked than the unsigned type, 337 // but isn't actually any bigger (like unsigned int and long 338 // on most 32-bit systems). Use the unsigned type corresponding 339 // to the signed type. 340 destType = Context.getCorrespondingUnsignedType(lhsSigned ? lhs : rhs); 341 } 342 return destType; 343} 344 345//===----------------------------------------------------------------------===// 346// Semantic Analysis for various Expression Types 347//===----------------------------------------------------------------------===// 348 349 350/// ActOnStringLiteral - The specified tokens were lexed as pasted string 351/// fragments (e.g. "foo" "bar" L"baz"). The result string has to handle string 352/// concatenation ([C99 5.1.1.2, translation phase #6]), so it may come from 353/// multiple tokens. However, the common case is that StringToks points to one 354/// string. 355/// 356Action::OwningExprResult 357Sema::ActOnStringLiteral(const Token *StringToks, unsigned NumStringToks) { 358 assert(NumStringToks && "Must have at least one string!"); 359 360 StringLiteralParser Literal(StringToks, NumStringToks, PP); 361 if (Literal.hadError) 362 return ExprError(); 363 364 llvm::SmallVector<SourceLocation, 4> StringTokLocs; 365 for (unsigned i = 0; i != NumStringToks; ++i) 366 StringTokLocs.push_back(StringToks[i].getLocation()); 367 368 QualType StrTy = Context.CharTy; 369 if (Literal.AnyWide) StrTy = Context.getWCharType(); 370 if (Literal.Pascal) StrTy = Context.UnsignedCharTy; 371 372 // A C++ string literal has a const-qualified element type (C++ 2.13.4p1). 373 if (getLangOptions().CPlusPlus) 374 StrTy.addConst(); 375 376 // Get an array type for the string, according to C99 6.4.5. This includes 377 // the nul terminator character as well as the string length for pascal 378 // strings. 379 StrTy = Context.getConstantArrayType(StrTy, 380 llvm::APInt(32, Literal.GetNumStringChars()+1), 381 ArrayType::Normal, 0); 382 383 // Pass &StringTokLocs[0], StringTokLocs.size() to factory! 384 return Owned(StringLiteral::Create(Context, Literal.GetString(), 385 Literal.GetStringLength(), 386 Literal.AnyWide, StrTy, 387 &StringTokLocs[0], 388 StringTokLocs.size())); 389} 390 391/// ShouldSnapshotBlockValueReference - Return true if a reference inside of 392/// CurBlock to VD should cause it to be snapshotted (as we do for auto 393/// variables defined outside the block) or false if this is not needed (e.g. 394/// for values inside the block or for globals). 395/// 396/// FIXME: This will create BlockDeclRefExprs for global variables, 397/// function references, etc which is suboptimal :) and breaks 398/// things like "integer constant expression" tests. 399static bool ShouldSnapshotBlockValueReference(BlockSemaInfo *CurBlock, 400 ValueDecl *VD) { 401 // If the value is defined inside the block, we couldn't snapshot it even if 402 // we wanted to. 403 if (CurBlock->TheDecl == VD->getDeclContext()) 404 return false; 405 406 // If this is an enum constant or function, it is constant, don't snapshot. 407 if (isa<EnumConstantDecl>(VD) || isa<FunctionDecl>(VD)) 408 return false; 409 410 // If this is a reference to an extern, static, or global variable, no need to 411 // snapshot it. 412 // FIXME: What about 'const' variables in C++? 413 if (const VarDecl *Var = dyn_cast<VarDecl>(VD)) 414 return Var->hasLocalStorage(); 415 416 return true; 417} 418 419 420 421/// ActOnIdentifierExpr - The parser read an identifier in expression context, 422/// validate it per-C99 6.5.1. HasTrailingLParen indicates whether this 423/// identifier is used in a function call context. 424/// SS is only used for a C++ qualified-id (foo::bar) to indicate the 425/// class or namespace that the identifier must be a member of. 426Sema::OwningExprResult Sema::ActOnIdentifierExpr(Scope *S, SourceLocation Loc, 427 IdentifierInfo &II, 428 bool HasTrailingLParen, 429 const CXXScopeSpec *SS, 430 bool isAddressOfOperand) { 431 return ActOnDeclarationNameExpr(S, Loc, &II, HasTrailingLParen, SS, 432 isAddressOfOperand); 433} 434 435/// BuildDeclRefExpr - Build either a DeclRefExpr or a 436/// QualifiedDeclRefExpr based on whether or not SS is a 437/// nested-name-specifier. 438DeclRefExpr * 439Sema::BuildDeclRefExpr(NamedDecl *D, QualType Ty, SourceLocation Loc, 440 bool TypeDependent, bool ValueDependent, 441 const CXXScopeSpec *SS) { 442 if (SS && !SS->isEmpty()) 443 return new (Context) QualifiedDeclRefExpr(D, Ty, Loc, TypeDependent, 444 ValueDependent, 445 SS->getRange().getBegin()); 446 else 447 return new (Context) DeclRefExpr(D, Ty, Loc, TypeDependent, ValueDependent); 448} 449 450/// getObjectForAnonymousRecordDecl - Retrieve the (unnamed) field or 451/// variable corresponding to the anonymous union or struct whose type 452/// is Record. 453static Decl *getObjectForAnonymousRecordDecl(RecordDecl *Record) { 454 assert(Record->isAnonymousStructOrUnion() && 455 "Record must be an anonymous struct or union!"); 456 457 // FIXME: Once Decls are directly linked together, this will 458 // be an O(1) operation rather than a slow walk through DeclContext's 459 // vector (which itself will be eliminated). DeclGroups might make 460 // this even better. 461 DeclContext *Ctx = Record->getDeclContext(); 462 for (DeclContext::decl_iterator D = Ctx->decls_begin(), 463 DEnd = Ctx->decls_end(); 464 D != DEnd; ++D) { 465 if (*D == Record) { 466 // The object for the anonymous struct/union directly 467 // follows its type in the list of declarations. 468 ++D; 469 assert(D != DEnd && "Missing object for anonymous record"); 470 assert(!cast<NamedDecl>(*D)->getDeclName() && "Decl should be unnamed"); 471 return *D; 472 } 473 } 474 475 assert(false && "Missing object for anonymous record"); 476 return 0; 477} 478 479Sema::OwningExprResult 480Sema::BuildAnonymousStructUnionMemberReference(SourceLocation Loc, 481 FieldDecl *Field, 482 Expr *BaseObjectExpr, 483 SourceLocation OpLoc) { 484 assert(Field->getDeclContext()->isRecord() && 485 cast<RecordDecl>(Field->getDeclContext())->isAnonymousStructOrUnion() 486 && "Field must be stored inside an anonymous struct or union"); 487 488 // Construct the sequence of field member references 489 // we'll have to perform to get to the field in the anonymous 490 // union/struct. The list of members is built from the field 491 // outward, so traverse it backwards to go from an object in 492 // the current context to the field we found. 493 llvm::SmallVector<FieldDecl *, 4> AnonFields; 494 AnonFields.push_back(Field); 495 VarDecl *BaseObject = 0; 496 DeclContext *Ctx = Field->getDeclContext(); 497 do { 498 RecordDecl *Record = cast<RecordDecl>(Ctx); 499 Decl *AnonObject = getObjectForAnonymousRecordDecl(Record); 500 if (FieldDecl *AnonField = dyn_cast<FieldDecl>(AnonObject)) 501 AnonFields.push_back(AnonField); 502 else { 503 BaseObject = cast<VarDecl>(AnonObject); 504 break; 505 } 506 Ctx = Ctx->getParent(); 507 } while (Ctx->isRecord() && 508 cast<RecordDecl>(Ctx)->isAnonymousStructOrUnion()); 509 510 // Build the expression that refers to the base object, from 511 // which we will build a sequence of member references to each 512 // of the anonymous union objects and, eventually, the field we 513 // found via name lookup. 514 bool BaseObjectIsPointer = false; 515 unsigned ExtraQuals = 0; 516 if (BaseObject) { 517 // BaseObject is an anonymous struct/union variable (and is, 518 // therefore, not part of another non-anonymous record). 519 if (BaseObjectExpr) BaseObjectExpr->Destroy(Context); 520 BaseObjectExpr = new (Context) DeclRefExpr(BaseObject,BaseObject->getType(), 521 SourceLocation()); 522 ExtraQuals 523 = Context.getCanonicalType(BaseObject->getType()).getCVRQualifiers(); 524 } else if (BaseObjectExpr) { 525 // The caller provided the base object expression. Determine 526 // whether its a pointer and whether it adds any qualifiers to the 527 // anonymous struct/union fields we're looking into. 528 QualType ObjectType = BaseObjectExpr->getType(); 529 if (const PointerType *ObjectPtr = ObjectType->getAsPointerType()) { 530 BaseObjectIsPointer = true; 531 ObjectType = ObjectPtr->getPointeeType(); 532 } 533 ExtraQuals = Context.getCanonicalType(ObjectType).getCVRQualifiers(); 534 } else { 535 // We've found a member of an anonymous struct/union that is 536 // inside a non-anonymous struct/union, so in a well-formed 537 // program our base object expression is "this". 538 if (CXXMethodDecl *MD = dyn_cast<CXXMethodDecl>(CurContext)) { 539 if (!MD->isStatic()) { 540 QualType AnonFieldType 541 = Context.getTagDeclType( 542 cast<RecordDecl>(AnonFields.back()->getDeclContext())); 543 QualType ThisType = Context.getTagDeclType(MD->getParent()); 544 if ((Context.getCanonicalType(AnonFieldType) 545 == Context.getCanonicalType(ThisType)) || 546 IsDerivedFrom(ThisType, AnonFieldType)) { 547 // Our base object expression is "this". 548 BaseObjectExpr = new (Context) CXXThisExpr(SourceLocation(), 549 MD->getThisType(Context)); 550 BaseObjectIsPointer = true; 551 } 552 } else { 553 return ExprError(Diag(Loc,diag::err_invalid_member_use_in_static_method) 554 << Field->getDeclName()); 555 } 556 ExtraQuals = MD->getTypeQualifiers(); 557 } 558 559 if (!BaseObjectExpr) 560 return ExprError(Diag(Loc, diag::err_invalid_non_static_member_use) 561 << Field->getDeclName()); 562 } 563 564 // Build the implicit member references to the field of the 565 // anonymous struct/union. 566 Expr *Result = BaseObjectExpr; 567 for (llvm::SmallVector<FieldDecl *, 4>::reverse_iterator 568 FI = AnonFields.rbegin(), FIEnd = AnonFields.rend(); 569 FI != FIEnd; ++FI) { 570 QualType MemberType = (*FI)->getType(); 571 if (!(*FI)->isMutable()) { 572 unsigned combinedQualifiers 573 = MemberType.getCVRQualifiers() | ExtraQuals; 574 MemberType = MemberType.getQualifiedType(combinedQualifiers); 575 } 576 Result = new (Context) MemberExpr(Result, BaseObjectIsPointer, *FI, 577 OpLoc, MemberType); 578 BaseObjectIsPointer = false; 579 ExtraQuals = Context.getCanonicalType(MemberType).getCVRQualifiers(); 580 } 581 582 return Owned(Result); 583} 584 585/// ActOnDeclarationNameExpr - The parser has read some kind of name 586/// (e.g., a C++ id-expression (C++ [expr.prim]p1)). This routine 587/// performs lookup on that name and returns an expression that refers 588/// to that name. This routine isn't directly called from the parser, 589/// because the parser doesn't know about DeclarationName. Rather, 590/// this routine is called by ActOnIdentifierExpr, 591/// ActOnOperatorFunctionIdExpr, and ActOnConversionFunctionExpr, 592/// which form the DeclarationName from the corresponding syntactic 593/// forms. 594/// 595/// HasTrailingLParen indicates whether this identifier is used in a 596/// function call context. LookupCtx is only used for a C++ 597/// qualified-id (foo::bar) to indicate the class or namespace that 598/// the identifier must be a member of. 599/// 600/// isAddressOfOperand means that this expression is the direct operand 601/// of an address-of operator. This matters because this is the only 602/// situation where a qualified name referencing a non-static member may 603/// appear outside a member function of this class. 604Sema::OwningExprResult 605Sema::ActOnDeclarationNameExpr(Scope *S, SourceLocation Loc, 606 DeclarationName Name, bool HasTrailingLParen, 607 const CXXScopeSpec *SS, 608 bool isAddressOfOperand) { 609 // Could be enum-constant, value decl, instance variable, etc. 610 if (SS && SS->isInvalid()) 611 return ExprError(); 612 LookupResult Lookup = LookupParsedName(S, SS, Name, LookupOrdinaryName, 613 false, true, Loc); 614 615 NamedDecl *D = 0; 616 if (Lookup.isAmbiguous()) { 617 DiagnoseAmbiguousLookup(Lookup, Name, Loc, 618 SS && SS->isSet() ? SS->getRange() 619 : SourceRange()); 620 return ExprError(); 621 } else 622 D = Lookup.getAsDecl(); 623 624 // If this reference is in an Objective-C method, then ivar lookup happens as 625 // well. 626 IdentifierInfo *II = Name.getAsIdentifierInfo(); 627 if (II && getCurMethodDecl()) { 628 // There are two cases to handle here. 1) scoped lookup could have failed, 629 // in which case we should look for an ivar. 2) scoped lookup could have 630 // found a decl, but that decl is outside the current instance method (i.e. 631 // a global variable). In these two cases, we do a lookup for an ivar with 632 // this name, if the lookup sucedes, we replace it our current decl. 633 if (D == 0 || D->isDefinedOutsideFunctionOrMethod()) { 634 ObjCInterfaceDecl *IFace = getCurMethodDecl()->getClassInterface(); 635 ObjCInterfaceDecl *ClassDeclared; 636 if (ObjCIvarDecl *IV = IFace->lookupInstanceVariable(II, ClassDeclared)) { 637 // Check if referencing a field with __attribute__((deprecated)). 638 if (DiagnoseUseOfDecl(IV, Loc)) 639 return ExprError(); 640 bool IsClsMethod = getCurMethodDecl()->isClassMethod(); 641 // If a class method attemps to use a free standing ivar, this is 642 // an error. 643 if (IsClsMethod && D && !D->isDefinedOutsideFunctionOrMethod()) 644 return ExprError(Diag(Loc, diag::error_ivar_use_in_class_method) 645 << IV->getDeclName()); 646 // If a class method uses a global variable, even if an ivar with 647 // same name exists, use the global. 648 if (!IsClsMethod) { 649 if (IV->getAccessControl() == ObjCIvarDecl::Private && 650 ClassDeclared != IFace) 651 Diag(Loc, diag::error_private_ivar_access) << IV->getDeclName(); 652 // FIXME: This should use a new expr for a direct reference, don't turn 653 // this into Self->ivar, just return a BareIVarExpr or something. 654 IdentifierInfo &II = Context.Idents.get("self"); 655 OwningExprResult SelfExpr = ActOnIdentifierExpr(S, Loc, II, false); 656 ObjCIvarRefExpr *MRef = new (Context) ObjCIvarRefExpr(IV, IV->getType(), 657 Loc, static_cast<Expr*>(SelfExpr.release()), 658 true, true); 659 Context.setFieldDecl(IFace, IV, MRef); 660 return Owned(MRef); 661 } 662 } 663 } 664 else if (getCurMethodDecl()->isInstanceMethod()) { 665 // We should warn if a local variable hides an ivar. 666 ObjCInterfaceDecl *IFace = getCurMethodDecl()->getClassInterface(); 667 ObjCInterfaceDecl *ClassDeclared; 668 if (ObjCIvarDecl *IV = IFace->lookupInstanceVariable(II, ClassDeclared)) { 669 if (IV->getAccessControl() != ObjCIvarDecl::Private || 670 IFace == ClassDeclared) 671 Diag(Loc, diag::warn_ivar_use_hidden)<<IV->getDeclName(); 672 } 673 } 674 // Needed to implement property "super.method" notation. 675 if (D == 0 && II->isStr("super")) { 676 QualType T; 677 678 if (getCurMethodDecl()->isInstanceMethod()) 679 T = Context.getPointerType(Context.getObjCInterfaceType( 680 getCurMethodDecl()->getClassInterface())); 681 else 682 T = Context.getObjCClassType(); 683 return Owned(new (Context) ObjCSuperExpr(Loc, T)); 684 } 685 } 686 687 // Determine whether this name might be a candidate for 688 // argument-dependent lookup. 689 bool ADL = getLangOptions().CPlusPlus && (!SS || !SS->isSet()) && 690 HasTrailingLParen; 691 692 if (ADL && D == 0) { 693 // We've seen something of the form 694 // 695 // identifier( 696 // 697 // and we did not find any entity by the name 698 // "identifier". However, this identifier is still subject to 699 // argument-dependent lookup, so keep track of the name. 700 return Owned(new (Context) UnresolvedFunctionNameExpr(Name, 701 Context.OverloadTy, 702 Loc)); 703 } 704 705 if (D == 0) { 706 // Otherwise, this could be an implicitly declared function reference (legal 707 // in C90, extension in C99). 708 if (HasTrailingLParen && II && 709 !getLangOptions().CPlusPlus) // Not in C++. 710 D = ImplicitlyDefineFunction(Loc, *II, S); 711 else { 712 // If this name wasn't predeclared and if this is not a function call, 713 // diagnose the problem. 714 if (SS && !SS->isEmpty()) 715 return ExprError(Diag(Loc, diag::err_typecheck_no_member) 716 << Name << SS->getRange()); 717 else if (Name.getNameKind() == DeclarationName::CXXOperatorName || 718 Name.getNameKind() == DeclarationName::CXXConversionFunctionName) 719 return ExprError(Diag(Loc, diag::err_undeclared_use) 720 << Name.getAsString()); 721 else 722 return ExprError(Diag(Loc, diag::err_undeclared_var_use) << Name); 723 } 724 } 725 726 // If this is an expression of the form &Class::member, don't build an 727 // implicit member ref, because we want a pointer to the member in general, 728 // not any specific instance's member. 729 if (isAddressOfOperand && SS && !SS->isEmpty() && !HasTrailingLParen) { 730 DeclContext *DC = getScopeRepAsDeclContext(*SS); 731 if (D && isa<CXXRecordDecl>(DC)) { 732 QualType DType; 733 if (FieldDecl *FD = dyn_cast<FieldDecl>(D)) { 734 DType = FD->getType().getNonReferenceType(); 735 } else if (CXXMethodDecl *Method = dyn_cast<CXXMethodDecl>(D)) { 736 DType = Method->getType(); 737 } else if (isa<OverloadedFunctionDecl>(D)) { 738 DType = Context.OverloadTy; 739 } 740 // Could be an inner type. That's diagnosed below, so ignore it here. 741 if (!DType.isNull()) { 742 // The pointer is type- and value-dependent if it points into something 743 // dependent. 744 bool Dependent = false; 745 for (; DC; DC = DC->getParent()) { 746 // FIXME: could stop early at namespace scope. 747 if (DC->isRecord()) { 748 CXXRecordDecl *Record = cast<CXXRecordDecl>(DC); 749 if (Context.getTypeDeclType(Record)->isDependentType()) { 750 Dependent = true; 751 break; 752 } 753 } 754 } 755 return Owned(BuildDeclRefExpr(D, DType, Loc, Dependent, Dependent, SS)); 756 } 757 } 758 } 759 760 // We may have found a field within an anonymous union or struct 761 // (C++ [class.union]). 762 if (FieldDecl *FD = dyn_cast<FieldDecl>(D)) 763 if (cast<RecordDecl>(FD->getDeclContext())->isAnonymousStructOrUnion()) 764 return BuildAnonymousStructUnionMemberReference(Loc, FD); 765 766 if (CXXMethodDecl *MD = dyn_cast<CXXMethodDecl>(CurContext)) { 767 if (!MD->isStatic()) { 768 // C++ [class.mfct.nonstatic]p2: 769 // [...] if name lookup (3.4.1) resolves the name in the 770 // id-expression to a nonstatic nontype member of class X or of 771 // a base class of X, the id-expression is transformed into a 772 // class member access expression (5.2.5) using (*this) (9.3.2) 773 // as the postfix-expression to the left of the '.' operator. 774 DeclContext *Ctx = 0; 775 QualType MemberType; 776 if (FieldDecl *FD = dyn_cast<FieldDecl>(D)) { 777 Ctx = FD->getDeclContext(); 778 MemberType = FD->getType(); 779 780 if (const ReferenceType *RefType = MemberType->getAsReferenceType()) 781 MemberType = RefType->getPointeeType(); 782 else if (!FD->isMutable()) { 783 unsigned combinedQualifiers 784 = MemberType.getCVRQualifiers() | MD->getTypeQualifiers(); 785 MemberType = MemberType.getQualifiedType(combinedQualifiers); 786 } 787 } else if (CXXMethodDecl *Method = dyn_cast<CXXMethodDecl>(D)) { 788 if (!Method->isStatic()) { 789 Ctx = Method->getParent(); 790 MemberType = Method->getType(); 791 } 792 } else if (OverloadedFunctionDecl *Ovl 793 = dyn_cast<OverloadedFunctionDecl>(D)) { 794 for (OverloadedFunctionDecl::function_iterator 795 Func = Ovl->function_begin(), 796 FuncEnd = Ovl->function_end(); 797 Func != FuncEnd; ++Func) { 798 if (CXXMethodDecl *DMethod = dyn_cast<CXXMethodDecl>(*Func)) 799 if (!DMethod->isStatic()) { 800 Ctx = Ovl->getDeclContext(); 801 MemberType = Context.OverloadTy; 802 break; 803 } 804 } 805 } 806 807 if (Ctx && Ctx->isRecord()) { 808 QualType CtxType = Context.getTagDeclType(cast<CXXRecordDecl>(Ctx)); 809 QualType ThisType = Context.getTagDeclType(MD->getParent()); 810 if ((Context.getCanonicalType(CtxType) 811 == Context.getCanonicalType(ThisType)) || 812 IsDerivedFrom(ThisType, CtxType)) { 813 // Build the implicit member access expression. 814 Expr *This = new (Context) CXXThisExpr(SourceLocation(), 815 MD->getThisType(Context)); 816 return Owned(new (Context) MemberExpr(This, true, D, 817 SourceLocation(), MemberType)); 818 } 819 } 820 } 821 } 822 823 if (FieldDecl *FD = dyn_cast<FieldDecl>(D)) { 824 if (CXXMethodDecl *MD = dyn_cast<CXXMethodDecl>(CurContext)) { 825 if (MD->isStatic()) 826 // "invalid use of member 'x' in static member function" 827 return ExprError(Diag(Loc,diag::err_invalid_member_use_in_static_method) 828 << FD->getDeclName()); 829 } 830 831 // Any other ways we could have found the field in a well-formed 832 // program would have been turned into implicit member expressions 833 // above. 834 return ExprError(Diag(Loc, diag::err_invalid_non_static_member_use) 835 << FD->getDeclName()); 836 } 837 838 if (isa<TypedefDecl>(D)) 839 return ExprError(Diag(Loc, diag::err_unexpected_typedef) << Name); 840 if (isa<ObjCInterfaceDecl>(D)) 841 return ExprError(Diag(Loc, diag::err_unexpected_interface) << Name); 842 if (isa<NamespaceDecl>(D)) 843 return ExprError(Diag(Loc, diag::err_unexpected_namespace) << Name); 844 845 // Make the DeclRefExpr or BlockDeclRefExpr for the decl. 846 if (OverloadedFunctionDecl *Ovl = dyn_cast<OverloadedFunctionDecl>(D)) 847 return Owned(BuildDeclRefExpr(Ovl, Context.OverloadTy, Loc, 848 false, false, SS)); 849 else if (TemplateDecl *Template = dyn_cast<TemplateDecl>(D)) 850 return Owned(BuildDeclRefExpr(Template, Context.OverloadTy, Loc, 851 false, false, SS)); 852 ValueDecl *VD = cast<ValueDecl>(D); 853 854 // Check whether this declaration can be used. Note that we suppress 855 // this check when we're going to perform argument-dependent lookup 856 // on this function name, because this might not be the function 857 // that overload resolution actually selects. 858 if (!(ADL && isa<FunctionDecl>(VD)) && DiagnoseUseOfDecl(VD, Loc)) 859 return ExprError(); 860 861 if (VarDecl *Var = dyn_cast<VarDecl>(VD)) { 862 // Warn about constructs like: 863 // if (void *X = foo()) { ... } else { X }. 864 // In the else block, the pointer is always false. 865 if (Var->isDeclaredInCondition() && Var->getType()->isScalarType()) { 866 Scope *CheckS = S; 867 while (CheckS) { 868 if (CheckS->isWithinElse() && 869 CheckS->getControlParent()->isDeclScope(Var)) { 870 if (Var->getType()->isBooleanType()) 871 ExprError(Diag(Loc, diag::warn_value_always_false) 872 << Var->getDeclName()); 873 else 874 ExprError(Diag(Loc, diag::warn_value_always_zero) 875 << Var->getDeclName()); 876 break; 877 } 878 879 // Move up one more control parent to check again. 880 CheckS = CheckS->getControlParent(); 881 if (CheckS) 882 CheckS = CheckS->getParent(); 883 } 884 } 885 } else if (FunctionDecl *Func = dyn_cast<FunctionDecl>(VD)) { 886 if (!getLangOptions().CPlusPlus && !Func->hasPrototype()) { 887 // C99 DR 316 says that, if a function type comes from a 888 // function definition (without a prototype), that type is only 889 // used for checking compatibility. Therefore, when referencing 890 // the function, we pretend that we don't have the full function 891 // type. 892 QualType T = Func->getType(); 893 QualType NoProtoType = T; 894 if (const FunctionProtoType *Proto = T->getAsFunctionProtoType()) 895 NoProtoType = Context.getFunctionNoProtoType(Proto->getResultType()); 896 return Owned(BuildDeclRefExpr(VD, NoProtoType, Loc, false, false, SS)); 897 } 898 } 899 900 // Only create DeclRefExpr's for valid Decl's. 901 if (VD->isInvalidDecl()) 902 return ExprError(); 903 904 // If the identifier reference is inside a block, and it refers to a value 905 // that is outside the block, create a BlockDeclRefExpr instead of a 906 // DeclRefExpr. This ensures the value is treated as a copy-in snapshot when 907 // the block is formed. 908 // 909 // We do not do this for things like enum constants, global variables, etc, 910 // as they do not get snapshotted. 911 // 912 if (CurBlock && ShouldSnapshotBlockValueReference(CurBlock, VD)) { 913 // Blocks that have these can't be constant. 914 CurBlock->hasBlockDeclRefExprs = true; 915 916 // The BlocksAttr indicates the variable is bound by-reference. 917 if (VD->getAttr<BlocksAttr>()) 918 return Owned(new (Context) BlockDeclRefExpr(VD, 919 VD->getType().getNonReferenceType(), Loc, true)); 920 921 // Variable will be bound by-copy, make it const within the closure. 922 VD->getType().addConst(); 923 return Owned(new (Context) BlockDeclRefExpr(VD, 924 VD->getType().getNonReferenceType(), Loc, false)); 925 } 926 // If this reference is not in a block or if the referenced variable is 927 // within the block, create a normal DeclRefExpr. 928 929 bool TypeDependent = false; 930 bool ValueDependent = false; 931 if (getLangOptions().CPlusPlus) { 932 // C++ [temp.dep.expr]p3: 933 // An id-expression is type-dependent if it contains: 934 // - an identifier that was declared with a dependent type, 935 if (VD->getType()->isDependentType()) 936 TypeDependent = true; 937 // - FIXME: a template-id that is dependent, 938 // - a conversion-function-id that specifies a dependent type, 939 else if (Name.getNameKind() == DeclarationName::CXXConversionFunctionName && 940 Name.getCXXNameType()->isDependentType()) 941 TypeDependent = true; 942 // - a nested-name-specifier that contains a class-name that 943 // names a dependent type. 944 else if (SS && !SS->isEmpty()) { 945 for (DeclContext *DC = getScopeRepAsDeclContext(*SS); 946 DC; DC = DC->getParent()) { 947 // FIXME: could stop early at namespace scope. 948 if (DC->isRecord()) { 949 CXXRecordDecl *Record = cast<CXXRecordDecl>(DC); 950 if (Context.getTypeDeclType(Record)->isDependentType()) { 951 TypeDependent = true; 952 break; 953 } 954 } 955 } 956 } 957 958 // C++ [temp.dep.constexpr]p2: 959 // 960 // An identifier is value-dependent if it is: 961 // - a name declared with a dependent type, 962 if (TypeDependent) 963 ValueDependent = true; 964 // - the name of a non-type template parameter, 965 else if (isa<NonTypeTemplateParmDecl>(VD)) 966 ValueDependent = true; 967 // - a constant with integral or enumeration type and is 968 // initialized with an expression that is value-dependent 969 // (FIXME!). 970 } 971 972 return Owned(BuildDeclRefExpr(VD, VD->getType().getNonReferenceType(), Loc, 973 TypeDependent, ValueDependent, SS)); 974} 975 976Sema::OwningExprResult Sema::ActOnPredefinedExpr(SourceLocation Loc, 977 tok::TokenKind Kind) { 978 PredefinedExpr::IdentType IT; 979 980 switch (Kind) { 981 default: assert(0 && "Unknown simple primary expr!"); 982 case tok::kw___func__: IT = PredefinedExpr::Func; break; // [C99 6.4.2.2] 983 case tok::kw___FUNCTION__: IT = PredefinedExpr::Function; break; 984 case tok::kw___PRETTY_FUNCTION__: IT = PredefinedExpr::PrettyFunction; break; 985 } 986 987 // Pre-defined identifiers are of type char[x], where x is the length of the 988 // string. 989 unsigned Length; 990 if (FunctionDecl *FD = getCurFunctionDecl()) 991 Length = FD->getIdentifier()->getLength(); 992 else if (ObjCMethodDecl *MD = getCurMethodDecl()) 993 Length = MD->getSynthesizedMethodSize(); 994 else { 995 Diag(Loc, diag::ext_predef_outside_function); 996 // __PRETTY_FUNCTION__ -> "top level", the others produce an empty string. 997 Length = IT == PredefinedExpr::PrettyFunction ? strlen("top level") : 0; 998 } 999 1000 1001 llvm::APInt LengthI(32, Length + 1); 1002 QualType ResTy = Context.CharTy.getQualifiedType(QualType::Const); 1003 ResTy = Context.getConstantArrayType(ResTy, LengthI, ArrayType::Normal, 0); 1004 return Owned(new (Context) PredefinedExpr(Loc, ResTy, IT)); 1005} 1006 1007Sema::OwningExprResult Sema::ActOnCharacterConstant(const Token &Tok) { 1008 llvm::SmallString<16> CharBuffer; 1009 CharBuffer.resize(Tok.getLength()); 1010 const char *ThisTokBegin = &CharBuffer[0]; 1011 unsigned ActualLength = PP.getSpelling(Tok, ThisTokBegin); 1012 1013 CharLiteralParser Literal(ThisTokBegin, ThisTokBegin+ActualLength, 1014 Tok.getLocation(), PP); 1015 if (Literal.hadError()) 1016 return ExprError(); 1017 1018 QualType type = getLangOptions().CPlusPlus ? Context.CharTy : Context.IntTy; 1019 1020 return Owned(new (Context) CharacterLiteral(Literal.getValue(), 1021 Literal.isWide(), 1022 type, Tok.getLocation())); 1023} 1024 1025Action::OwningExprResult Sema::ActOnNumericConstant(const Token &Tok) { 1026 // Fast path for a single digit (which is quite common). A single digit 1027 // cannot have a trigraph, escaped newline, radix prefix, or type suffix. 1028 if (Tok.getLength() == 1) { 1029 const char Val = PP.getSpellingOfSingleCharacterNumericConstant(Tok); 1030 unsigned IntSize = Context.Target.getIntWidth(); 1031 return Owned(new (Context) IntegerLiteral(llvm::APInt(IntSize, Val-'0'), 1032 Context.IntTy, Tok.getLocation())); 1033 } 1034 1035 llvm::SmallString<512> IntegerBuffer; 1036 // Add padding so that NumericLiteralParser can overread by one character. 1037 IntegerBuffer.resize(Tok.getLength()+1); 1038 const char *ThisTokBegin = &IntegerBuffer[0]; 1039 1040 // Get the spelling of the token, which eliminates trigraphs, etc. 1041 unsigned ActualLength = PP.getSpelling(Tok, ThisTokBegin); 1042 1043 NumericLiteralParser Literal(ThisTokBegin, ThisTokBegin+ActualLength, 1044 Tok.getLocation(), PP); 1045 if (Literal.hadError) 1046 return ExprError(); 1047 1048 Expr *Res; 1049 1050 if (Literal.isFloatingLiteral()) { 1051 QualType Ty; 1052 if (Literal.isFloat) 1053 Ty = Context.FloatTy; 1054 else if (!Literal.isLong) 1055 Ty = Context.DoubleTy; 1056 else 1057 Ty = Context.LongDoubleTy; 1058 1059 const llvm::fltSemantics &Format = Context.getFloatTypeSemantics(Ty); 1060 1061 // isExact will be set by GetFloatValue(). 1062 bool isExact = false; 1063 Res = new (Context) FloatingLiteral(Literal.GetFloatValue(Format, &isExact), 1064 &isExact, Ty, Tok.getLocation()); 1065 1066 } else if (!Literal.isIntegerLiteral()) { 1067 return ExprError(); 1068 } else { 1069 QualType Ty; 1070 1071 // long long is a C99 feature. 1072 if (!getLangOptions().C99 && !getLangOptions().CPlusPlus0x && 1073 Literal.isLongLong) 1074 Diag(Tok.getLocation(), diag::ext_longlong); 1075 1076 // Get the value in the widest-possible width. 1077 llvm::APInt ResultVal(Context.Target.getIntMaxTWidth(), 0); 1078 1079 if (Literal.GetIntegerValue(ResultVal)) { 1080 // If this value didn't fit into uintmax_t, warn and force to ull. 1081 Diag(Tok.getLocation(), diag::warn_integer_too_large); 1082 Ty = Context.UnsignedLongLongTy; 1083 assert(Context.getTypeSize(Ty) == ResultVal.getBitWidth() && 1084 "long long is not intmax_t?"); 1085 } else { 1086 // If this value fits into a ULL, try to figure out what else it fits into 1087 // according to the rules of C99 6.4.4.1p5. 1088 1089 // Octal, Hexadecimal, and integers with a U suffix are allowed to 1090 // be an unsigned int. 1091 bool AllowUnsigned = Literal.isUnsigned || Literal.getRadix() != 10; 1092 1093 // Check from smallest to largest, picking the smallest type we can. 1094 unsigned Width = 0; 1095 if (!Literal.isLong && !Literal.isLongLong) { 1096 // Are int/unsigned possibilities? 1097 unsigned IntSize = Context.Target.getIntWidth(); 1098 1099 // Does it fit in a unsigned int? 1100 if (ResultVal.isIntN(IntSize)) { 1101 // Does it fit in a signed int? 1102 if (!Literal.isUnsigned && ResultVal[IntSize-1] == 0) 1103 Ty = Context.IntTy; 1104 else if (AllowUnsigned) 1105 Ty = Context.UnsignedIntTy; 1106 Width = IntSize; 1107 } 1108 } 1109 1110 // Are long/unsigned long possibilities? 1111 if (Ty.isNull() && !Literal.isLongLong) { 1112 unsigned LongSize = Context.Target.getLongWidth(); 1113 1114 // Does it fit in a unsigned long? 1115 if (ResultVal.isIntN(LongSize)) { 1116 // Does it fit in a signed long? 1117 if (!Literal.isUnsigned && ResultVal[LongSize-1] == 0) 1118 Ty = Context.LongTy; 1119 else if (AllowUnsigned) 1120 Ty = Context.UnsignedLongTy; 1121 Width = LongSize; 1122 } 1123 } 1124 1125 // Finally, check long long if needed. 1126 if (Ty.isNull()) { 1127 unsigned LongLongSize = Context.Target.getLongLongWidth(); 1128 1129 // Does it fit in a unsigned long long? 1130 if (ResultVal.isIntN(LongLongSize)) { 1131 // Does it fit in a signed long long? 1132 if (!Literal.isUnsigned && ResultVal[LongLongSize-1] == 0) 1133 Ty = Context.LongLongTy; 1134 else if (AllowUnsigned) 1135 Ty = Context.UnsignedLongLongTy; 1136 Width = LongLongSize; 1137 } 1138 } 1139 1140 // If we still couldn't decide a type, we probably have something that 1141 // does not fit in a signed long long, but has no U suffix. 1142 if (Ty.isNull()) { 1143 Diag(Tok.getLocation(), diag::warn_integer_too_large_for_signed); 1144 Ty = Context.UnsignedLongLongTy; 1145 Width = Context.Target.getLongLongWidth(); 1146 } 1147 1148 if (ResultVal.getBitWidth() != Width) 1149 ResultVal.trunc(Width); 1150 } 1151 Res = new (Context) IntegerLiteral(ResultVal, Ty, Tok.getLocation()); 1152 } 1153 1154 // If this is an imaginary literal, create the ImaginaryLiteral wrapper. 1155 if (Literal.isImaginary) 1156 Res = new (Context) ImaginaryLiteral(Res, 1157 Context.getComplexType(Res->getType())); 1158 1159 return Owned(Res); 1160} 1161 1162Action::OwningExprResult Sema::ActOnParenExpr(SourceLocation L, 1163 SourceLocation R, ExprArg Val) { 1164 Expr *E = (Expr *)Val.release(); 1165 assert((E != 0) && "ActOnParenExpr() missing expr"); 1166 return Owned(new (Context) ParenExpr(L, R, E)); 1167} 1168 1169/// The UsualUnaryConversions() function is *not* called by this routine. 1170/// See C99 6.3.2.1p[2-4] for more details. 1171bool Sema::CheckSizeOfAlignOfOperand(QualType exprType, 1172 SourceLocation OpLoc, 1173 const SourceRange &ExprRange, 1174 bool isSizeof) { 1175 if (exprType->isDependentType()) 1176 return false; 1177 1178 // C99 6.5.3.4p1: 1179 if (isa<FunctionType>(exprType)) { 1180 // alignof(function) is allowed. 1181 if (isSizeof) 1182 Diag(OpLoc, diag::ext_sizeof_function_type) << ExprRange; 1183 return false; 1184 } 1185 1186 if (exprType->isVoidType()) { 1187 Diag(OpLoc, diag::ext_sizeof_void_type) 1188 << (isSizeof ? "sizeof" : "__alignof") << ExprRange; 1189 return false; 1190 } 1191 1192 return RequireCompleteType(OpLoc, exprType, 1193 isSizeof ? diag::err_sizeof_incomplete_type : 1194 diag::err_alignof_incomplete_type, 1195 ExprRange); 1196} 1197 1198bool Sema::CheckAlignOfExpr(Expr *E, SourceLocation OpLoc, 1199 const SourceRange &ExprRange) { 1200 E = E->IgnoreParens(); 1201 1202 // alignof decl is always ok. 1203 if (isa<DeclRefExpr>(E)) 1204 return false; 1205 1206 // Cannot know anything else if the expression is dependent. 1207 if (E->isTypeDependent()) 1208 return false; 1209 1210 if (MemberExpr *ME = dyn_cast<MemberExpr>(E)) { 1211 if (FieldDecl *FD = dyn_cast<FieldDecl>(ME->getMemberDecl())) { 1212 if (FD->isBitField()) { 1213 Diag(OpLoc, diag::err_sizeof_alignof_bitfield) << 1 << ExprRange; 1214 return true; 1215 } 1216 // Other fields are ok. 1217 return false; 1218 } 1219 } 1220 return CheckSizeOfAlignOfOperand(E->getType(), OpLoc, ExprRange, false); 1221} 1222 1223/// \brief Build a sizeof or alignof expression given a type operand. 1224Action::OwningExprResult 1225Sema::CreateSizeOfAlignOfExpr(QualType T, SourceLocation OpLoc, 1226 bool isSizeOf, SourceRange R) { 1227 if (T.isNull()) 1228 return ExprError(); 1229 1230 if (!T->isDependentType() && 1231 CheckSizeOfAlignOfOperand(T, OpLoc, R, isSizeOf)) 1232 return ExprError(); 1233 1234 // C99 6.5.3.4p4: the type (an unsigned integer type) is size_t. 1235 return Owned(new (Context) SizeOfAlignOfExpr(isSizeOf, T, 1236 Context.getSizeType(), OpLoc, 1237 R.getEnd())); 1238} 1239 1240/// \brief Build a sizeof or alignof expression given an expression 1241/// operand. 1242Action::OwningExprResult 1243Sema::CreateSizeOfAlignOfExpr(Expr *E, SourceLocation OpLoc, 1244 bool isSizeOf, SourceRange R) { 1245 // Verify that the operand is valid. 1246 bool isInvalid = false; 1247 if (E->isTypeDependent()) { 1248 // Delay type-checking for type-dependent expressions. 1249 } else if (!isSizeOf) { 1250 isInvalid = CheckAlignOfExpr(E, OpLoc, R); 1251 } else if (E->isBitField()) { // C99 6.5.3.4p1. 1252 Diag(OpLoc, diag::err_sizeof_alignof_bitfield) << 0; 1253 isInvalid = true; 1254 } else { 1255 isInvalid = CheckSizeOfAlignOfOperand(E->getType(), OpLoc, R, true); 1256 } 1257 1258 if (isInvalid) 1259 return ExprError(); 1260 1261 // C99 6.5.3.4p4: the type (an unsigned integer type) is size_t. 1262 return Owned(new (Context) SizeOfAlignOfExpr(isSizeOf, E, 1263 Context.getSizeType(), OpLoc, 1264 R.getEnd())); 1265} 1266 1267/// ActOnSizeOfAlignOfExpr - Handle @c sizeof(type) and @c sizeof @c expr and 1268/// the same for @c alignof and @c __alignof 1269/// Note that the ArgRange is invalid if isType is false. 1270Action::OwningExprResult 1271Sema::ActOnSizeOfAlignOfExpr(SourceLocation OpLoc, bool isSizeof, bool isType, 1272 void *TyOrEx, const SourceRange &ArgRange) { 1273 // If error parsing type, ignore. 1274 if (TyOrEx == 0) return ExprError(); 1275 1276 if (isType) { 1277 QualType ArgTy = QualType::getFromOpaquePtr(TyOrEx); 1278 return CreateSizeOfAlignOfExpr(ArgTy, OpLoc, isSizeof, ArgRange); 1279 } 1280 1281 // Get the end location. 1282 Expr *ArgEx = (Expr *)TyOrEx; 1283 Action::OwningExprResult Result 1284 = CreateSizeOfAlignOfExpr(ArgEx, OpLoc, isSizeof, ArgEx->getSourceRange()); 1285 1286 if (Result.isInvalid()) 1287 DeleteExpr(ArgEx); 1288 1289 return move(Result); 1290} 1291 1292QualType Sema::CheckRealImagOperand(Expr *&V, SourceLocation Loc, bool isReal) { 1293 if (V->isTypeDependent()) 1294 return Context.DependentTy; 1295 1296 DefaultFunctionArrayConversion(V); 1297 1298 // These operators return the element type of a complex type. 1299 if (const ComplexType *CT = V->getType()->getAsComplexType()) 1300 return CT->getElementType(); 1301 1302 // Otherwise they pass through real integer and floating point types here. 1303 if (V->getType()->isArithmeticType()) 1304 return V->getType(); 1305 1306 // Reject anything else. 1307 Diag(Loc, diag::err_realimag_invalid_type) << V->getType() 1308 << (isReal ? "__real" : "__imag"); 1309 return QualType(); 1310} 1311 1312 1313 1314Action::OwningExprResult 1315Sema::ActOnPostfixUnaryOp(Scope *S, SourceLocation OpLoc, 1316 tok::TokenKind Kind, ExprArg Input) { 1317 Expr *Arg = (Expr *)Input.get(); 1318 1319 UnaryOperator::Opcode Opc; 1320 switch (Kind) { 1321 default: assert(0 && "Unknown unary op!"); 1322 case tok::plusplus: Opc = UnaryOperator::PostInc; break; 1323 case tok::minusminus: Opc = UnaryOperator::PostDec; break; 1324 } 1325 1326 if (getLangOptions().CPlusPlus && 1327 (Arg->getType()->isRecordType() || Arg->getType()->isEnumeralType())) { 1328 // Which overloaded operator? 1329 OverloadedOperatorKind OverOp = 1330 (Opc == UnaryOperator::PostInc)? OO_PlusPlus : OO_MinusMinus; 1331 1332 // C++ [over.inc]p1: 1333 // 1334 // [...] If the function is a member function with one 1335 // parameter (which shall be of type int) or a non-member 1336 // function with two parameters (the second of which shall be 1337 // of type int), it defines the postfix increment operator ++ 1338 // for objects of that type. When the postfix increment is 1339 // called as a result of using the ++ operator, the int 1340 // argument will have value zero. 1341 Expr *Args[2] = { 1342 Arg, 1343 new (Context) IntegerLiteral(llvm::APInt(Context.Target.getIntWidth(), 0, 1344 /*isSigned=*/true), Context.IntTy, SourceLocation()) 1345 }; 1346 1347 // Build the candidate set for overloading 1348 OverloadCandidateSet CandidateSet; 1349 AddOperatorCandidates(OverOp, S, OpLoc, Args, 2, CandidateSet); 1350 1351 // Perform overload resolution. 1352 OverloadCandidateSet::iterator Best; 1353 switch (BestViableFunction(CandidateSet, Best)) { 1354 case OR_Success: { 1355 // We found a built-in operator or an overloaded operator. 1356 FunctionDecl *FnDecl = Best->Function; 1357 1358 if (FnDecl) { 1359 // We matched an overloaded operator. Build a call to that 1360 // operator. 1361 1362 // Convert the arguments. 1363 if (CXXMethodDecl *Method = dyn_cast<CXXMethodDecl>(FnDecl)) { 1364 if (PerformObjectArgumentInitialization(Arg, Method)) 1365 return ExprError(); 1366 } else { 1367 // Convert the arguments. 1368 if (PerformCopyInitialization(Arg, 1369 FnDecl->getParamDecl(0)->getType(), 1370 "passing")) 1371 return ExprError(); 1372 } 1373 1374 // Determine the result type 1375 QualType ResultTy 1376 = FnDecl->getType()->getAsFunctionType()->getResultType(); 1377 ResultTy = ResultTy.getNonReferenceType(); 1378 1379 // Build the actual expression node. 1380 Expr *FnExpr = new (Context) DeclRefExpr(FnDecl, FnDecl->getType(), 1381 SourceLocation()); 1382 UsualUnaryConversions(FnExpr); 1383 1384 Input.release(); 1385 return Owned(new (Context) CXXOperatorCallExpr(Context, OverOp, FnExpr, 1386 Args, 2, ResultTy, 1387 OpLoc)); 1388 } else { 1389 // We matched a built-in operator. Convert the arguments, then 1390 // break out so that we will build the appropriate built-in 1391 // operator node. 1392 if (PerformCopyInitialization(Arg, Best->BuiltinTypes.ParamTypes[0], 1393 "passing")) 1394 return ExprError(); 1395 1396 break; 1397 } 1398 } 1399 1400 case OR_No_Viable_Function: 1401 // No viable function; fall through to handling this as a 1402 // built-in operator, which will produce an error message for us. 1403 break; 1404 1405 case OR_Ambiguous: 1406 Diag(OpLoc, diag::err_ovl_ambiguous_oper) 1407 << UnaryOperator::getOpcodeStr(Opc) 1408 << Arg->getSourceRange(); 1409 PrintOverloadCandidates(CandidateSet, /*OnlyViable=*/true); 1410 return ExprError(); 1411 1412 case OR_Deleted: 1413 Diag(OpLoc, diag::err_ovl_deleted_oper) 1414 << Best->Function->isDeleted() 1415 << UnaryOperator::getOpcodeStr(Opc) 1416 << Arg->getSourceRange(); 1417 PrintOverloadCandidates(CandidateSet, /*OnlyViable=*/true); 1418 return ExprError(); 1419 } 1420 1421 // Either we found no viable overloaded operator or we matched a 1422 // built-in operator. In either case, fall through to trying to 1423 // build a built-in operation. 1424 } 1425 1426 QualType result = CheckIncrementDecrementOperand(Arg, OpLoc, 1427 Opc == UnaryOperator::PostInc); 1428 if (result.isNull()) 1429 return ExprError(); 1430 Input.release(); 1431 return Owned(new (Context) UnaryOperator(Arg, Opc, result, OpLoc)); 1432} 1433 1434Action::OwningExprResult 1435Sema::ActOnArraySubscriptExpr(Scope *S, ExprArg Base, SourceLocation LLoc, 1436 ExprArg Idx, SourceLocation RLoc) { 1437 Expr *LHSExp = static_cast<Expr*>(Base.get()), 1438 *RHSExp = static_cast<Expr*>(Idx.get()); 1439 1440 if (getLangOptions().CPlusPlus && 1441 (LHSExp->getType()->isRecordType() || 1442 LHSExp->getType()->isEnumeralType() || 1443 RHSExp->getType()->isRecordType() || 1444 RHSExp->getType()->isEnumeralType())) { 1445 // Add the appropriate overloaded operators (C++ [over.match.oper]) 1446 // to the candidate set. 1447 OverloadCandidateSet CandidateSet; 1448 Expr *Args[2] = { LHSExp, RHSExp }; 1449 AddOperatorCandidates(OO_Subscript, S, LLoc, Args, 2, CandidateSet, 1450 SourceRange(LLoc, RLoc)); 1451 1452 // Perform overload resolution. 1453 OverloadCandidateSet::iterator Best; 1454 switch (BestViableFunction(CandidateSet, Best)) { 1455 case OR_Success: { 1456 // We found a built-in operator or an overloaded operator. 1457 FunctionDecl *FnDecl = Best->Function; 1458 1459 if (FnDecl) { 1460 // We matched an overloaded operator. Build a call to that 1461 // operator. 1462 1463 // Convert the arguments. 1464 if (CXXMethodDecl *Method = dyn_cast<CXXMethodDecl>(FnDecl)) { 1465 if (PerformObjectArgumentInitialization(LHSExp, Method) || 1466 PerformCopyInitialization(RHSExp, 1467 FnDecl->getParamDecl(0)->getType(), 1468 "passing")) 1469 return ExprError(); 1470 } else { 1471 // Convert the arguments. 1472 if (PerformCopyInitialization(LHSExp, 1473 FnDecl->getParamDecl(0)->getType(), 1474 "passing") || 1475 PerformCopyInitialization(RHSExp, 1476 FnDecl->getParamDecl(1)->getType(), 1477 "passing")) 1478 return ExprError(); 1479 } 1480 1481 // Determine the result type 1482 QualType ResultTy 1483 = FnDecl->getType()->getAsFunctionType()->getResultType(); 1484 ResultTy = ResultTy.getNonReferenceType(); 1485 1486 // Build the actual expression node. 1487 Expr *FnExpr = new (Context) DeclRefExpr(FnDecl, FnDecl->getType(), 1488 SourceLocation()); 1489 UsualUnaryConversions(FnExpr); 1490 1491 Base.release(); 1492 Idx.release(); 1493 return Owned(new (Context) CXXOperatorCallExpr(Context, OO_Subscript, 1494 FnExpr, Args, 2, 1495 ResultTy, LLoc)); 1496 } else { 1497 // We matched a built-in operator. Convert the arguments, then 1498 // break out so that we will build the appropriate built-in 1499 // operator node. 1500 if (PerformCopyInitialization(LHSExp, Best->BuiltinTypes.ParamTypes[0], 1501 "passing") || 1502 PerformCopyInitialization(RHSExp, Best->BuiltinTypes.ParamTypes[1], 1503 "passing")) 1504 return ExprError(); 1505 1506 break; 1507 } 1508 } 1509 1510 case OR_No_Viable_Function: 1511 // No viable function; fall through to handling this as a 1512 // built-in operator, which will produce an error message for us. 1513 break; 1514 1515 case OR_Ambiguous: 1516 Diag(LLoc, diag::err_ovl_ambiguous_oper) 1517 << "[]" 1518 << LHSExp->getSourceRange() << RHSExp->getSourceRange(); 1519 PrintOverloadCandidates(CandidateSet, /*OnlyViable=*/true); 1520 return ExprError(); 1521 1522 case OR_Deleted: 1523 Diag(LLoc, diag::err_ovl_deleted_oper) 1524 << Best->Function->isDeleted() 1525 << "[]" 1526 << LHSExp->getSourceRange() << RHSExp->getSourceRange(); 1527 PrintOverloadCandidates(CandidateSet, /*OnlyViable=*/true); 1528 return ExprError(); 1529 } 1530 1531 // Either we found no viable overloaded operator or we matched a 1532 // built-in operator. In either case, fall through to trying to 1533 // build a built-in operation. 1534 } 1535 1536 // Perform default conversions. 1537 DefaultFunctionArrayConversion(LHSExp); 1538 DefaultFunctionArrayConversion(RHSExp); 1539 1540 QualType LHSTy = LHSExp->getType(), RHSTy = RHSExp->getType(); 1541 1542 // C99 6.5.2.1p2: the expression e1[e2] is by definition precisely equivalent 1543 // to the expression *((e1)+(e2)). This means the array "Base" may actually be 1544 // in the subscript position. As a result, we need to derive the array base 1545 // and index from the expression types. 1546 Expr *BaseExpr, *IndexExpr; 1547 QualType ResultType; 1548 if (LHSTy->isDependentType() || RHSTy->isDependentType()) { 1549 BaseExpr = LHSExp; 1550 IndexExpr = RHSExp; 1551 ResultType = Context.DependentTy; 1552 } else if (const PointerType *PTy = LHSTy->getAsPointerType()) { 1553 BaseExpr = LHSExp; 1554 IndexExpr = RHSExp; 1555 // FIXME: need to deal with const... 1556 ResultType = PTy->getPointeeType(); 1557 } else if (const PointerType *PTy = RHSTy->getAsPointerType()) { 1558 // Handle the uncommon case of "123[Ptr]". 1559 BaseExpr = RHSExp; 1560 IndexExpr = LHSExp; 1561 // FIXME: need to deal with const... 1562 ResultType = PTy->getPointeeType(); 1563 } else if (const VectorType *VTy = LHSTy->getAsVectorType()) { 1564 BaseExpr = LHSExp; // vectors: V[123] 1565 IndexExpr = RHSExp; 1566 1567 // FIXME: need to deal with const... 1568 ResultType = VTy->getElementType(); 1569 } else { 1570 return ExprError(Diag(LHSExp->getLocStart(), 1571 diag::err_typecheck_subscript_value) << RHSExp->getSourceRange()); 1572 } 1573 // C99 6.5.2.1p1 1574 if (!IndexExpr->getType()->isIntegerType() && !IndexExpr->isTypeDependent()) 1575 return ExprError(Diag(IndexExpr->getLocStart(), 1576 diag::err_typecheck_subscript) << IndexExpr->getSourceRange()); 1577 1578 // C99 6.5.2.1p1: "shall have type "pointer to *object* type". In practice, 1579 // the following check catches trying to index a pointer to a function (e.g. 1580 // void (*)(int)) and pointers to incomplete types. Functions are not 1581 // objects in C99. 1582 if (!ResultType->isObjectType() && !ResultType->isDependentType()) 1583 return ExprError(Diag(BaseExpr->getLocStart(), 1584 diag::err_typecheck_subscript_not_object) 1585 << BaseExpr->getType() << BaseExpr->getSourceRange()); 1586 1587 Base.release(); 1588 Idx.release(); 1589 return Owned(new (Context) ArraySubscriptExpr(LHSExp, RHSExp, 1590 ResultType, RLoc)); 1591} 1592 1593QualType Sema:: 1594CheckExtVectorComponent(QualType baseType, SourceLocation OpLoc, 1595 IdentifierInfo &CompName, SourceLocation CompLoc) { 1596 const ExtVectorType *vecType = baseType->getAsExtVectorType(); 1597 1598 // The vector accessor can't exceed the number of elements. 1599 const char *compStr = CompName.getName(); 1600 1601 // This flag determines whether or not the component is one of the four 1602 // special names that indicate a subset of exactly half the elements are 1603 // to be selected. 1604 bool HalvingSwizzle = false; 1605 1606 // This flag determines whether or not CompName has an 's' char prefix, 1607 // indicating that it is a string of hex values to be used as vector indices. 1608 bool HexSwizzle = *compStr == 's'; 1609 1610 // Check that we've found one of the special components, or that the component 1611 // names must come from the same set. 1612 if (!strcmp(compStr, "hi") || !strcmp(compStr, "lo") || 1613 !strcmp(compStr, "even") || !strcmp(compStr, "odd")) { 1614 HalvingSwizzle = true; 1615 } else if (vecType->getPointAccessorIdx(*compStr) != -1) { 1616 do 1617 compStr++; 1618 while (*compStr && vecType->getPointAccessorIdx(*compStr) != -1); 1619 } else if (HexSwizzle || vecType->getNumericAccessorIdx(*compStr) != -1) { 1620 do 1621 compStr++; 1622 while (*compStr && vecType->getNumericAccessorIdx(*compStr) != -1); 1623 } 1624 1625 if (!HalvingSwizzle && *compStr) { 1626 // We didn't get to the end of the string. This means the component names 1627 // didn't come from the same set *or* we encountered an illegal name. 1628 Diag(OpLoc, diag::err_ext_vector_component_name_illegal) 1629 << std::string(compStr,compStr+1) << SourceRange(CompLoc); 1630 return QualType(); 1631 } 1632 1633 // Ensure no component accessor exceeds the width of the vector type it 1634 // operates on. 1635 if (!HalvingSwizzle) { 1636 compStr = CompName.getName(); 1637 1638 if (HexSwizzle) 1639 compStr++; 1640 1641 while (*compStr) { 1642 if (!vecType->isAccessorWithinNumElements(*compStr++)) { 1643 Diag(OpLoc, diag::err_ext_vector_component_exceeds_length) 1644 << baseType << SourceRange(CompLoc); 1645 return QualType(); 1646 } 1647 } 1648 } 1649 1650 // If this is a halving swizzle, verify that the base type has an even 1651 // number of elements. 1652 if (HalvingSwizzle && (vecType->getNumElements() & 1U)) { 1653 Diag(OpLoc, diag::err_ext_vector_component_requires_even) 1654 << baseType << SourceRange(CompLoc); 1655 return QualType(); 1656 } 1657 1658 // The component accessor looks fine - now we need to compute the actual type. 1659 // The vector type is implied by the component accessor. For example, 1660 // vec4.b is a float, vec4.xy is a vec2, vec4.rgb is a vec3, etc. 1661 // vec4.s0 is a float, vec4.s23 is a vec3, etc. 1662 // vec4.hi, vec4.lo, vec4.e, and vec4.o all return vec2. 1663 unsigned CompSize = HalvingSwizzle ? vecType->getNumElements() / 2 1664 : CompName.getLength(); 1665 if (HexSwizzle) 1666 CompSize--; 1667 1668 if (CompSize == 1) 1669 return vecType->getElementType(); 1670 1671 QualType VT = Context.getExtVectorType(vecType->getElementType(), CompSize); 1672 // Now look up the TypeDefDecl from the vector type. Without this, 1673 // diagostics look bad. We want extended vector types to appear built-in. 1674 for (unsigned i = 0, E = ExtVectorDecls.size(); i != E; ++i) { 1675 if (ExtVectorDecls[i]->getUnderlyingType() == VT) 1676 return Context.getTypedefType(ExtVectorDecls[i]); 1677 } 1678 return VT; // should never get here (a typedef type should always be found). 1679} 1680 1681 1682Action::OwningExprResult 1683Sema::ActOnMemberReferenceExpr(Scope *S, ExprArg Base, SourceLocation OpLoc, 1684 tok::TokenKind OpKind, SourceLocation MemberLoc, 1685 IdentifierInfo &Member, 1686 DeclTy *ObjCImpDecl) { 1687 Expr *BaseExpr = static_cast<Expr *>(Base.release()); 1688 assert(BaseExpr && "no record expression"); 1689 1690 // Perform default conversions. 1691 DefaultFunctionArrayConversion(BaseExpr); 1692 1693 QualType BaseType = BaseExpr->getType(); 1694 assert(!BaseType.isNull() && "no type for member expression"); 1695 1696 // Get the type being accessed in BaseType. If this is an arrow, the BaseExpr 1697 // must have pointer type, and the accessed type is the pointee. 1698 if (OpKind == tok::arrow) { 1699 if (const PointerType *PT = BaseType->getAsPointerType()) 1700 BaseType = PT->getPointeeType(); 1701 else if (getLangOptions().CPlusPlus && BaseType->isRecordType()) 1702 return Owned(BuildOverloadedArrowExpr(S, BaseExpr, OpLoc, 1703 MemberLoc, Member)); 1704 else 1705 return ExprError(Diag(MemberLoc, 1706 diag::err_typecheck_member_reference_arrow) 1707 << BaseType << BaseExpr->getSourceRange()); 1708 } 1709 1710 // Handle field access to simple records. This also handles access to fields 1711 // of the ObjC 'id' struct. 1712 if (const RecordType *RTy = BaseType->getAsRecordType()) { 1713 RecordDecl *RDecl = RTy->getDecl(); 1714 if (RequireCompleteType(OpLoc, BaseType, 1715 diag::err_typecheck_incomplete_tag, 1716 BaseExpr->getSourceRange())) 1717 return ExprError(); 1718 1719 // The record definition is complete, now make sure the member is valid. 1720 // FIXME: Qualified name lookup for C++ is a bit more complicated 1721 // than this. 1722 LookupResult Result 1723 = LookupQualifiedName(RDecl, DeclarationName(&Member), 1724 LookupMemberName, false); 1725 1726 NamedDecl *MemberDecl = 0; 1727 if (!Result) 1728 return ExprError(Diag(MemberLoc, diag::err_typecheck_no_member) 1729 << &Member << BaseExpr->getSourceRange()); 1730 else if (Result.isAmbiguous()) { 1731 DiagnoseAmbiguousLookup(Result, DeclarationName(&Member), 1732 MemberLoc, BaseExpr->getSourceRange()); 1733 return ExprError(); 1734 } else 1735 MemberDecl = Result; 1736 1737 // If the decl being referenced had an error, return an error for this 1738 // sub-expr without emitting another error, in order to avoid cascading 1739 // error cases. 1740 if (MemberDecl->isInvalidDecl()) 1741 return ExprError(); 1742 1743 // Check the use of this field 1744 if (DiagnoseUseOfDecl(MemberDecl, MemberLoc)) 1745 return ExprError(); 1746 1747 if (FieldDecl *FD = dyn_cast<FieldDecl>(MemberDecl)) { 1748 // We may have found a field within an anonymous union or struct 1749 // (C++ [class.union]). 1750 if (cast<RecordDecl>(FD->getDeclContext())->isAnonymousStructOrUnion()) 1751 return BuildAnonymousStructUnionMemberReference(MemberLoc, FD, 1752 BaseExpr, OpLoc); 1753 1754 // Figure out the type of the member; see C99 6.5.2.3p3, C++ [expr.ref] 1755 // FIXME: Handle address space modifiers 1756 QualType MemberType = FD->getType(); 1757 if (const ReferenceType *Ref = MemberType->getAsReferenceType()) 1758 MemberType = Ref->getPointeeType(); 1759 else { 1760 unsigned combinedQualifiers = 1761 MemberType.getCVRQualifiers() | BaseType.getCVRQualifiers(); 1762 if (FD->isMutable()) 1763 combinedQualifiers &= ~QualType::Const; 1764 MemberType = MemberType.getQualifiedType(combinedQualifiers); 1765 } 1766 1767 return Owned(new (Context) MemberExpr(BaseExpr, OpKind == tok::arrow, FD, 1768 MemberLoc, MemberType)); 1769 } else if (VarDecl *Var = dyn_cast<VarDecl>(MemberDecl)) 1770 return Owned(new (Context) MemberExpr(BaseExpr, OpKind == tok::arrow, 1771 Var, MemberLoc, 1772 Var->getType().getNonReferenceType())); 1773 else if (FunctionDecl *MemberFn = dyn_cast<FunctionDecl>(MemberDecl)) 1774 return Owned(new (Context) MemberExpr(BaseExpr, OpKind == tok::arrow, 1775 MemberFn, MemberLoc, MemberFn->getType())); 1776 else if (OverloadedFunctionDecl *Ovl 1777 = dyn_cast<OverloadedFunctionDecl>(MemberDecl)) 1778 return Owned(new (Context) MemberExpr(BaseExpr, OpKind == tok::arrow, Ovl, 1779 MemberLoc, Context.OverloadTy)); 1780 else if (EnumConstantDecl *Enum = dyn_cast<EnumConstantDecl>(MemberDecl)) 1781 return Owned(new (Context) MemberExpr(BaseExpr, OpKind == tok::arrow, 1782 Enum, MemberLoc, Enum->getType())); 1783 else if (isa<TypeDecl>(MemberDecl)) 1784 return ExprError(Diag(MemberLoc,diag::err_typecheck_member_reference_type) 1785 << DeclarationName(&Member) << int(OpKind == tok::arrow)); 1786 1787 // We found a declaration kind that we didn't expect. This is a 1788 // generic error message that tells the user that she can't refer 1789 // to this member with '.' or '->'. 1790 return ExprError(Diag(MemberLoc, 1791 diag::err_typecheck_member_reference_unknown) 1792 << DeclarationName(&Member) << int(OpKind == tok::arrow)); 1793 } 1794 1795 // Handle access to Objective-C instance variables, such as "Obj->ivar" and 1796 // (*Obj).ivar. 1797 if (const ObjCInterfaceType *IFTy = BaseType->getAsObjCInterfaceType()) { 1798 ObjCInterfaceDecl *ClassDeclared; 1799 if (ObjCIvarDecl *IV = IFTy->getDecl()->lookupInstanceVariable(&Member, 1800 ClassDeclared)) { 1801 // If the decl being referenced had an error, return an error for this 1802 // sub-expr without emitting another error, in order to avoid cascading 1803 // error cases. 1804 if (IV->isInvalidDecl()) 1805 return ExprError(); 1806 1807 // Check whether we can reference this field. 1808 if (DiagnoseUseOfDecl(IV, MemberLoc)) 1809 return ExprError(); 1810 if (IV->getAccessControl() != ObjCIvarDecl::Public) { 1811 ObjCInterfaceDecl *ClassOfMethodDecl = 0; 1812 if (ObjCMethodDecl *MD = getCurMethodDecl()) 1813 ClassOfMethodDecl = MD->getClassInterface(); 1814 else if (ObjCImpDecl && getCurFunctionDecl()) { 1815 // Case of a c-function declared inside an objc implementation. 1816 // FIXME: For a c-style function nested inside an objc implementation 1817 // class, there is no implementation context available, so we pass down 1818 // the context as argument to this routine. Ideally, this context need 1819 // be passed down in the AST node and somehow calculated from the AST 1820 // for a function decl. 1821 Decl *ImplDecl = static_cast<Decl *>(ObjCImpDecl); 1822 if (ObjCImplementationDecl *IMPD = 1823 dyn_cast<ObjCImplementationDecl>(ImplDecl)) 1824 ClassOfMethodDecl = IMPD->getClassInterface(); 1825 else if (ObjCCategoryImplDecl* CatImplClass = 1826 dyn_cast<ObjCCategoryImplDecl>(ImplDecl)) 1827 ClassOfMethodDecl = CatImplClass->getClassInterface(); 1828 } 1829 if (IV->getAccessControl() == ObjCIvarDecl::Private) { 1830 if (ClassDeclared != IFTy->getDecl() || 1831 ClassOfMethodDecl != ClassDeclared) 1832 Diag(MemberLoc, diag::error_private_ivar_access) << IV->getDeclName(); 1833 } 1834 // @protected 1835 else if (!IFTy->getDecl()->isSuperClassOf(ClassOfMethodDecl)) 1836 Diag(MemberLoc, diag::error_protected_ivar_access) << IV->getDeclName(); 1837 } 1838 1839 ObjCIvarRefExpr *MRef= new (Context) ObjCIvarRefExpr(IV, IV->getType(), 1840 MemberLoc, BaseExpr, 1841 OpKind == tok::arrow); 1842 Context.setFieldDecl(IFTy->getDecl(), IV, MRef); 1843 return Owned(MRef); 1844 } 1845 return ExprError(Diag(MemberLoc, diag::err_typecheck_member_reference_ivar) 1846 << IFTy->getDecl()->getDeclName() << &Member 1847 << BaseExpr->getSourceRange()); 1848 } 1849 1850 // Handle Objective-C property access, which is "Obj.property" where Obj is a 1851 // pointer to a (potentially qualified) interface type. 1852 const PointerType *PTy; 1853 const ObjCInterfaceType *IFTy; 1854 if (OpKind == tok::period && (PTy = BaseType->getAsPointerType()) && 1855 (IFTy = PTy->getPointeeType()->getAsObjCInterfaceType())) { 1856 ObjCInterfaceDecl *IFace = IFTy->getDecl(); 1857 1858 // Search for a declared property first. 1859 if (ObjCPropertyDecl *PD = IFace->FindPropertyDeclaration(&Member)) { 1860 // Check whether we can reference this property. 1861 if (DiagnoseUseOfDecl(PD, MemberLoc)) 1862 return ExprError(); 1863 1864 return Owned(new (Context) ObjCPropertyRefExpr(PD, PD->getType(), 1865 MemberLoc, BaseExpr)); 1866 } 1867 1868 // Check protocols on qualified interfaces. 1869 for (ObjCInterfaceType::qual_iterator I = IFTy->qual_begin(), 1870 E = IFTy->qual_end(); I != E; ++I) 1871 if (ObjCPropertyDecl *PD = (*I)->FindPropertyDeclaration(&Member)) { 1872 // Check whether we can reference this property. 1873 if (DiagnoseUseOfDecl(PD, MemberLoc)) 1874 return ExprError(); 1875 1876 return Owned(new (Context) ObjCPropertyRefExpr(PD, PD->getType(), 1877 MemberLoc, BaseExpr)); 1878 } 1879 1880 // If that failed, look for an "implicit" property by seeing if the nullary 1881 // selector is implemented. 1882 1883 // FIXME: The logic for looking up nullary and unary selectors should be 1884 // shared with the code in ActOnInstanceMessage. 1885 1886 Selector Sel = PP.getSelectorTable().getNullarySelector(&Member); 1887 ObjCMethodDecl *Getter = IFace->lookupInstanceMethod(Sel); 1888 1889 // If this reference is in an @implementation, check for 'private' methods. 1890 if (!Getter) 1891 if (ObjCImplementationDecl *ImpDecl = 1892 ObjCImplementations[IFace->getIdentifier()]) 1893 Getter = ImpDecl->getInstanceMethod(Sel); 1894 1895 // Look through local category implementations associated with the class. 1896 if (!Getter) { 1897 for (unsigned i = 0; i < ObjCCategoryImpls.size() && !Getter; i++) { 1898 if (ObjCCategoryImpls[i]->getClassInterface() == IFace) 1899 Getter = ObjCCategoryImpls[i]->getInstanceMethod(Sel); 1900 } 1901 } 1902 if (Getter) { 1903 // Check if we can reference this property. 1904 if (DiagnoseUseOfDecl(Getter, MemberLoc)) 1905 return ExprError(); 1906 } 1907 // If we found a getter then this may be a valid dot-reference, we 1908 // will look for the matching setter, in case it is needed. 1909 Selector SetterSel = 1910 SelectorTable::constructSetterName(PP.getIdentifierTable(), 1911 PP.getSelectorTable(), &Member); 1912 ObjCMethodDecl *Setter = IFace->lookupInstanceMethod(SetterSel); 1913 if (!Setter) { 1914 // If this reference is in an @implementation, also check for 'private' 1915 // methods. 1916 if (ObjCImplementationDecl *ImpDecl = 1917 ObjCImplementations[IFace->getIdentifier()]) 1918 Setter = ImpDecl->getInstanceMethod(SetterSel); 1919 } 1920 // Look through local category implementations associated with the class. 1921 if (!Setter) { 1922 for (unsigned i = 0; i < ObjCCategoryImpls.size() && !Setter; i++) { 1923 if (ObjCCategoryImpls[i]->getClassInterface() == IFace) 1924 Setter = ObjCCategoryImpls[i]->getInstanceMethod(SetterSel); 1925 } 1926 } 1927 1928 if (Setter && DiagnoseUseOfDecl(Setter, MemberLoc)) 1929 return ExprError(); 1930 1931 if (Getter || Setter) { 1932 QualType PType; 1933 1934 if (Getter) 1935 PType = Getter->getResultType(); 1936 else { 1937 for (ObjCMethodDecl::param_iterator PI = Setter->param_begin(), 1938 E = Setter->param_end(); PI != E; ++PI) 1939 PType = (*PI)->getType(); 1940 } 1941 // FIXME: we must check that the setter has property type. 1942 return Owned(new (Context) ObjCKVCRefExpr(Getter, PType, 1943 Setter, MemberLoc, BaseExpr)); 1944 } 1945 return ExprError(Diag(MemberLoc, diag::err_property_not_found) 1946 << &Member << BaseType); 1947 } 1948 // Handle properties on qualified "id" protocols. 1949 const ObjCQualifiedIdType *QIdTy; 1950 if (OpKind == tok::period && (QIdTy = BaseType->getAsObjCQualifiedIdType())) { 1951 // Check protocols on qualified interfaces. 1952 for (ObjCQualifiedIdType::qual_iterator I = QIdTy->qual_begin(), 1953 E = QIdTy->qual_end(); I != E; ++I) { 1954 if (ObjCPropertyDecl *PD = (*I)->FindPropertyDeclaration(&Member)) { 1955 // Check the use of this declaration 1956 if (DiagnoseUseOfDecl(PD, MemberLoc)) 1957 return ExprError(); 1958 1959 return Owned(new (Context) ObjCPropertyRefExpr(PD, PD->getType(), 1960 MemberLoc, BaseExpr)); 1961 } 1962 // Also must look for a getter name which uses property syntax. 1963 Selector Sel = PP.getSelectorTable().getNullarySelector(&Member); 1964 if (ObjCMethodDecl *OMD = (*I)->getInstanceMethod(Sel)) { 1965 // Check the use of this method. 1966 if (DiagnoseUseOfDecl(OMD, MemberLoc)) 1967 return ExprError(); 1968 1969 return Owned(new (Context) ObjCMessageExpr(BaseExpr, Sel, 1970 OMD->getResultType(), OMD, OpLoc, MemberLoc, NULL, 0)); 1971 } 1972 } 1973 1974 return ExprError(Diag(MemberLoc, diag::err_property_not_found) 1975 << &Member << BaseType); 1976 } 1977 // Handle properties on ObjC 'Class' types. 1978 if (OpKind == tok::period && (BaseType == Context.getObjCClassType())) { 1979 // Also must look for a getter name which uses property syntax. 1980 Selector Sel = PP.getSelectorTable().getNullarySelector(&Member); 1981 if (ObjCMethodDecl *MD = getCurMethodDecl()) { 1982 ObjCInterfaceDecl *IFace = MD->getClassInterface(); 1983 ObjCMethodDecl *Getter; 1984 // FIXME: need to also look locally in the implementation. 1985 if ((Getter = IFace->lookupClassMethod(Sel))) { 1986 // Check the use of this method. 1987 if (DiagnoseUseOfDecl(Getter, MemberLoc)) 1988 return ExprError(); 1989 } 1990 // If we found a getter then this may be a valid dot-reference, we 1991 // will look for the matching setter, in case it is needed. 1992 Selector SetterSel = 1993 SelectorTable::constructSetterName(PP.getIdentifierTable(), 1994 PP.getSelectorTable(), &Member); 1995 ObjCMethodDecl *Setter = IFace->lookupClassMethod(SetterSel); 1996 if (!Setter) { 1997 // If this reference is in an @implementation, also check for 'private' 1998 // methods. 1999 if (ObjCImplementationDecl *ImpDecl = 2000 ObjCImplementations[IFace->getIdentifier()]) 2001 Setter = ImpDecl->getInstanceMethod(SetterSel); 2002 } 2003 // Look through local category implementations associated with the class. 2004 if (!Setter) { 2005 for (unsigned i = 0; i < ObjCCategoryImpls.size() && !Setter; i++) { 2006 if (ObjCCategoryImpls[i]->getClassInterface() == IFace) 2007 Setter = ObjCCategoryImpls[i]->getClassMethod(SetterSel); 2008 } 2009 } 2010 2011 if (Setter && DiagnoseUseOfDecl(Setter, MemberLoc)) 2012 return ExprError(); 2013 2014 if (Getter || Setter) { 2015 QualType PType; 2016 2017 if (Getter) 2018 PType = Getter->getResultType(); 2019 else { 2020 for (ObjCMethodDecl::param_iterator PI = Setter->param_begin(), 2021 E = Setter->param_end(); PI != E; ++PI) 2022 PType = (*PI)->getType(); 2023 } 2024 // FIXME: we must check that the setter has property type. 2025 return Owned(new (Context) ObjCKVCRefExpr(Getter, PType, 2026 Setter, MemberLoc, BaseExpr)); 2027 } 2028 return ExprError(Diag(MemberLoc, diag::err_property_not_found) 2029 << &Member << BaseType); 2030 } 2031 } 2032 2033 // Handle 'field access' to vectors, such as 'V.xx'. 2034 if (BaseType->isExtVectorType()) { 2035 QualType ret = CheckExtVectorComponent(BaseType, OpLoc, Member, MemberLoc); 2036 if (ret.isNull()) 2037 return ExprError(); 2038 return Owned(new (Context) ExtVectorElementExpr(ret, BaseExpr, Member, 2039 MemberLoc)); 2040 } 2041 2042 return ExprError(Diag(MemberLoc, 2043 diag::err_typecheck_member_reference_struct_union) 2044 << BaseType << BaseExpr->getSourceRange()); 2045} 2046 2047/// ConvertArgumentsForCall - Converts the arguments specified in 2048/// Args/NumArgs to the parameter types of the function FDecl with 2049/// function prototype Proto. Call is the call expression itself, and 2050/// Fn is the function expression. For a C++ member function, this 2051/// routine does not attempt to convert the object argument. Returns 2052/// true if the call is ill-formed. 2053bool 2054Sema::ConvertArgumentsForCall(CallExpr *Call, Expr *Fn, 2055 FunctionDecl *FDecl, 2056 const FunctionProtoType *Proto, 2057 Expr **Args, unsigned NumArgs, 2058 SourceLocation RParenLoc) { 2059 // C99 6.5.2.2p7 - the arguments are implicitly converted, as if by 2060 // assignment, to the types of the corresponding parameter, ... 2061 unsigned NumArgsInProto = Proto->getNumArgs(); 2062 unsigned NumArgsToCheck = NumArgs; 2063 bool Invalid = false; 2064 2065 // If too few arguments are available (and we don't have default 2066 // arguments for the remaining parameters), don't make the call. 2067 if (NumArgs < NumArgsInProto) { 2068 if (!FDecl || NumArgs < FDecl->getMinRequiredArguments()) 2069 return Diag(RParenLoc, diag::err_typecheck_call_too_few_args) 2070 << Fn->getType()->isBlockPointerType() << Fn->getSourceRange(); 2071 // Use default arguments for missing arguments 2072 NumArgsToCheck = NumArgsInProto; 2073 Call->setNumArgs(Context, NumArgsInProto); 2074 } 2075 2076 // If too many are passed and not variadic, error on the extras and drop 2077 // them. 2078 if (NumArgs > NumArgsInProto) { 2079 if (!Proto->isVariadic()) { 2080 Diag(Args[NumArgsInProto]->getLocStart(), 2081 diag::err_typecheck_call_too_many_args) 2082 << Fn->getType()->isBlockPointerType() << Fn->getSourceRange() 2083 << SourceRange(Args[NumArgsInProto]->getLocStart(), 2084 Args[NumArgs-1]->getLocEnd()); 2085 // This deletes the extra arguments. 2086 Call->setNumArgs(Context, NumArgsInProto); 2087 Invalid = true; 2088 } 2089 NumArgsToCheck = NumArgsInProto; 2090 } 2091 2092 // Continue to check argument types (even if we have too few/many args). 2093 for (unsigned i = 0; i != NumArgsToCheck; i++) { 2094 QualType ProtoArgType = Proto->getArgType(i); 2095 2096 Expr *Arg; 2097 if (i < NumArgs) { 2098 Arg = Args[i]; 2099 2100 // Pass the argument. 2101 if (PerformCopyInitialization(Arg, ProtoArgType, "passing")) 2102 return true; 2103 } else 2104 // We already type-checked the argument, so we know it works. 2105 Arg = new (Context) CXXDefaultArgExpr(FDecl->getParamDecl(i)); 2106 QualType ArgType = Arg->getType(); 2107 2108 Call->setArg(i, Arg); 2109 } 2110 2111 // If this is a variadic call, handle args passed through "...". 2112 if (Proto->isVariadic()) { 2113 VariadicCallType CallType = VariadicFunction; 2114 if (Fn->getType()->isBlockPointerType()) 2115 CallType = VariadicBlock; // Block 2116 else if (isa<MemberExpr>(Fn)) 2117 CallType = VariadicMethod; 2118 2119 // Promote the arguments (C99 6.5.2.2p7). 2120 for (unsigned i = NumArgsInProto; i != NumArgs; i++) { 2121 Expr *Arg = Args[i]; 2122 DefaultVariadicArgumentPromotion(Arg, CallType); 2123 Call->setArg(i, Arg); 2124 } 2125 } 2126 2127 return Invalid; 2128} 2129 2130/// ActOnCallExpr - Handle a call to Fn with the specified array of arguments. 2131/// This provides the location of the left/right parens and a list of comma 2132/// locations. 2133Action::OwningExprResult 2134Sema::ActOnCallExpr(Scope *S, ExprArg fn, SourceLocation LParenLoc, 2135 MultiExprArg args, 2136 SourceLocation *CommaLocs, SourceLocation RParenLoc) { 2137 unsigned NumArgs = args.size(); 2138 Expr *Fn = static_cast<Expr *>(fn.release()); 2139 Expr **Args = reinterpret_cast<Expr**>(args.release()); 2140 assert(Fn && "no function call expression"); 2141 FunctionDecl *FDecl = NULL; 2142 DeclarationName UnqualifiedName; 2143 2144 if (getLangOptions().CPlusPlus) { 2145 // Determine whether this is a dependent call inside a C++ template, 2146 // in which case we won't do any semantic analysis now. 2147 // FIXME: Will need to cache the results of name lookup (including ADL) in Fn. 2148 bool Dependent = false; 2149 if (Fn->isTypeDependent()) 2150 Dependent = true; 2151 else if (Expr::hasAnyTypeDependentArguments(Args, NumArgs)) 2152 Dependent = true; 2153 2154 if (Dependent) 2155 return Owned(new (Context) CallExpr(Context, Fn, Args, NumArgs, 2156 Context.DependentTy, RParenLoc)); 2157 2158 // Determine whether this is a call to an object (C++ [over.call.object]). 2159 if (Fn->getType()->isRecordType()) 2160 return Owned(BuildCallToObjectOfClassType(S, Fn, LParenLoc, Args, NumArgs, 2161 CommaLocs, RParenLoc)); 2162 2163 // Determine whether this is a call to a member function. 2164 if (MemberExpr *MemExpr = dyn_cast<MemberExpr>(Fn->IgnoreParens())) 2165 if (isa<OverloadedFunctionDecl>(MemExpr->getMemberDecl()) || 2166 isa<CXXMethodDecl>(MemExpr->getMemberDecl())) 2167 return Owned(BuildCallToMemberFunction(S, Fn, LParenLoc, Args, NumArgs, 2168 CommaLocs, RParenLoc)); 2169 } 2170 2171 // If we're directly calling a function, get the appropriate declaration. 2172 DeclRefExpr *DRExpr = NULL; 2173 Expr *FnExpr = Fn; 2174 bool ADL = true; 2175 while (true) { 2176 if (ImplicitCastExpr *IcExpr = dyn_cast<ImplicitCastExpr>(FnExpr)) 2177 FnExpr = IcExpr->getSubExpr(); 2178 else if (ParenExpr *PExpr = dyn_cast<ParenExpr>(FnExpr)) { 2179 // Parentheses around a function disable ADL 2180 // (C++0x [basic.lookup.argdep]p1). 2181 ADL = false; 2182 FnExpr = PExpr->getSubExpr(); 2183 } else if (isa<UnaryOperator>(FnExpr) && 2184 cast<UnaryOperator>(FnExpr)->getOpcode() 2185 == UnaryOperator::AddrOf) { 2186 FnExpr = cast<UnaryOperator>(FnExpr)->getSubExpr(); 2187 } else if ((DRExpr = dyn_cast<DeclRefExpr>(FnExpr))) { 2188 // Qualified names disable ADL (C++0x [basic.lookup.argdep]p1). 2189 ADL &= !isa<QualifiedDeclRefExpr>(DRExpr); 2190 break; 2191 } else if (UnresolvedFunctionNameExpr *DepName 2192 = dyn_cast<UnresolvedFunctionNameExpr>(FnExpr)) { 2193 UnqualifiedName = DepName->getName(); 2194 break; 2195 } else { 2196 // Any kind of name that does not refer to a declaration (or 2197 // set of declarations) disables ADL (C++0x [basic.lookup.argdep]p3). 2198 ADL = false; 2199 break; 2200 } 2201 } 2202 2203 OverloadedFunctionDecl *Ovl = 0; 2204 if (DRExpr) { 2205 FDecl = dyn_cast<FunctionDecl>(DRExpr->getDecl()); 2206 Ovl = dyn_cast<OverloadedFunctionDecl>(DRExpr->getDecl()); 2207 } 2208 2209 if (Ovl || (getLangOptions().CPlusPlus && (FDecl || UnqualifiedName))) { 2210 // We don't perform ADL for implicit declarations of builtins. 2211 if (FDecl && FDecl->getBuiltinID(Context) && FDecl->isImplicit()) 2212 ADL = false; 2213 2214 // We don't perform ADL in C. 2215 if (!getLangOptions().CPlusPlus) 2216 ADL = false; 2217 2218 if (Ovl || ADL) { 2219 FDecl = ResolveOverloadedCallFn(Fn, DRExpr? DRExpr->getDecl() : 0, 2220 UnqualifiedName, LParenLoc, Args, 2221 NumArgs, CommaLocs, RParenLoc, ADL); 2222 if (!FDecl) 2223 return ExprError(); 2224 2225 // Update Fn to refer to the actual function selected. 2226 Expr *NewFn = 0; 2227 if (QualifiedDeclRefExpr *QDRExpr 2228 = dyn_cast_or_null<QualifiedDeclRefExpr>(DRExpr)) 2229 NewFn = new (Context) QualifiedDeclRefExpr(FDecl, FDecl->getType(), 2230 QDRExpr->getLocation(), 2231 false, false, 2232 QDRExpr->getSourceRange().getBegin()); 2233 else 2234 NewFn = new (Context) DeclRefExpr(FDecl, FDecl->getType(), 2235 Fn->getSourceRange().getBegin()); 2236 Fn->Destroy(Context); 2237 Fn = NewFn; 2238 } 2239 } 2240 2241 // Promote the function operand. 2242 UsualUnaryConversions(Fn); 2243 2244 // Make the call expr early, before semantic checks. This guarantees cleanup 2245 // of arguments and function on error. 2246 ExprOwningPtr<CallExpr> TheCall(this, new (Context) CallExpr(Context, Fn, 2247 Args, NumArgs, 2248 Context.BoolTy, 2249 RParenLoc)); 2250 2251 const FunctionType *FuncT; 2252 if (!Fn->getType()->isBlockPointerType()) { 2253 // C99 6.5.2.2p1 - "The expression that denotes the called function shall 2254 // have type pointer to function". 2255 const PointerType *PT = Fn->getType()->getAsPointerType(); 2256 if (PT == 0) 2257 return ExprError(Diag(LParenLoc, diag::err_typecheck_call_not_function) 2258 << Fn->getType() << Fn->getSourceRange()); 2259 FuncT = PT->getPointeeType()->getAsFunctionType(); 2260 } else { // This is a block call. 2261 FuncT = Fn->getType()->getAsBlockPointerType()->getPointeeType()-> 2262 getAsFunctionType(); 2263 } 2264 if (FuncT == 0) 2265 return ExprError(Diag(LParenLoc, diag::err_typecheck_call_not_function) 2266 << Fn->getType() << Fn->getSourceRange()); 2267 2268 // We know the result type of the call, set it. 2269 TheCall->setType(FuncT->getResultType().getNonReferenceType()); 2270 2271 if (const FunctionProtoType *Proto = dyn_cast<FunctionProtoType>(FuncT)) { 2272 if (ConvertArgumentsForCall(&*TheCall, Fn, FDecl, Proto, Args, NumArgs, 2273 RParenLoc)) 2274 return ExprError(); 2275 } else { 2276 assert(isa<FunctionNoProtoType>(FuncT) && "Unknown FunctionType!"); 2277 2278 // Promote the arguments (C99 6.5.2.2p6). 2279 for (unsigned i = 0; i != NumArgs; i++) { 2280 Expr *Arg = Args[i]; 2281 DefaultArgumentPromotion(Arg); 2282 TheCall->setArg(i, Arg); 2283 } 2284 } 2285 2286 if (CXXMethodDecl *Method = dyn_cast_or_null<CXXMethodDecl>(FDecl)) 2287 if (!Method->isStatic()) 2288 return ExprError(Diag(LParenLoc, diag::err_member_call_without_object) 2289 << Fn->getSourceRange()); 2290 2291 // Do special checking on direct calls to functions. 2292 if (FDecl) 2293 return CheckFunctionCall(FDecl, TheCall.take()); 2294 2295 return Owned(TheCall.take()); 2296} 2297 2298Action::OwningExprResult 2299Sema::ActOnCompoundLiteral(SourceLocation LParenLoc, TypeTy *Ty, 2300 SourceLocation RParenLoc, ExprArg InitExpr) { 2301 assert((Ty != 0) && "ActOnCompoundLiteral(): missing type"); 2302 QualType literalType = QualType::getFromOpaquePtr(Ty); 2303 // FIXME: put back this assert when initializers are worked out. 2304 //assert((InitExpr != 0) && "ActOnCompoundLiteral(): missing expression"); 2305 Expr *literalExpr = static_cast<Expr*>(InitExpr.get()); 2306 2307 if (literalType->isArrayType()) { 2308 if (literalType->isVariableArrayType()) 2309 return ExprError(Diag(LParenLoc, diag::err_variable_object_no_init) 2310 << SourceRange(LParenLoc, literalExpr->getSourceRange().getEnd())); 2311 } else if (RequireCompleteType(LParenLoc, literalType, 2312 diag::err_typecheck_decl_incomplete_type, 2313 SourceRange(LParenLoc, literalExpr->getSourceRange().getEnd()))) 2314 return ExprError(); 2315 2316 if (CheckInitializerTypes(literalExpr, literalType, LParenLoc, 2317 DeclarationName(), /*FIXME:DirectInit=*/false)) 2318 return ExprError(); 2319 2320 bool isFileScope = getCurFunctionOrMethodDecl() == 0; 2321 if (isFileScope) { // 6.5.2.5p3 2322 if (CheckForConstantInitializer(literalExpr, literalType)) 2323 return ExprError(); 2324 } 2325 InitExpr.release(); 2326 return Owned(new (Context) CompoundLiteralExpr(LParenLoc, literalType, 2327 literalExpr, isFileScope)); 2328} 2329 2330Action::OwningExprResult 2331Sema::ActOnInitList(SourceLocation LBraceLoc, MultiExprArg initlist, 2332 InitListDesignations &Designators, 2333 SourceLocation RBraceLoc) { 2334 unsigned NumInit = initlist.size(); 2335 Expr **InitList = reinterpret_cast<Expr**>(initlist.release()); 2336 2337 // Semantic analysis for initializers is done by ActOnDeclarator() and 2338 // CheckInitializer() - it requires knowledge of the object being intialized. 2339 2340 InitListExpr *E = new (Context) InitListExpr(LBraceLoc, InitList, NumInit, 2341 RBraceLoc); 2342 E->setType(Context.VoidTy); // FIXME: just a place holder for now. 2343 return Owned(E); 2344} 2345 2346/// CheckCastTypes - Check type constraints for casting between types. 2347bool Sema::CheckCastTypes(SourceRange TyR, QualType castType, Expr *&castExpr) { 2348 UsualUnaryConversions(castExpr); 2349 2350 // C99 6.5.4p2: the cast type needs to be void or scalar and the expression 2351 // type needs to be scalar. 2352 if (castType->isVoidType()) { 2353 // Cast to void allows any expr type. 2354 } else if (castType->isDependentType() || castExpr->isTypeDependent()) { 2355 // We can't check any more until template instantiation time. 2356 } else if (!castType->isScalarType() && !castType->isVectorType()) { 2357 if (Context.getCanonicalType(castType).getUnqualifiedType() == 2358 Context.getCanonicalType(castExpr->getType().getUnqualifiedType()) && 2359 (castType->isStructureType() || castType->isUnionType())) { 2360 // GCC struct/union extension: allow cast to self. 2361 Diag(TyR.getBegin(), diag::ext_typecheck_cast_nonscalar) 2362 << castType << castExpr->getSourceRange(); 2363 } else if (castType->isUnionType()) { 2364 // GCC cast to union extension 2365 RecordDecl *RD = castType->getAsRecordType()->getDecl(); 2366 RecordDecl::field_iterator Field, FieldEnd; 2367 for (Field = RD->field_begin(), FieldEnd = RD->field_end(); 2368 Field != FieldEnd; ++Field) { 2369 if (Context.getCanonicalType(Field->getType()).getUnqualifiedType() == 2370 Context.getCanonicalType(castExpr->getType()).getUnqualifiedType()) { 2371 Diag(TyR.getBegin(), diag::ext_typecheck_cast_to_union) 2372 << castExpr->getSourceRange(); 2373 break; 2374 } 2375 } 2376 if (Field == FieldEnd) 2377 return Diag(TyR.getBegin(), diag::err_typecheck_cast_to_union_no_type) 2378 << castExpr->getType() << castExpr->getSourceRange(); 2379 } else { 2380 // Reject any other conversions to non-scalar types. 2381 return Diag(TyR.getBegin(), diag::err_typecheck_cond_expect_scalar) 2382 << castType << castExpr->getSourceRange(); 2383 } 2384 } else if (!castExpr->getType()->isScalarType() && 2385 !castExpr->getType()->isVectorType()) { 2386 return Diag(castExpr->getLocStart(), 2387 diag::err_typecheck_expect_scalar_operand) 2388 << castExpr->getType() << castExpr->getSourceRange(); 2389 } else if (castExpr->getType()->isVectorType()) { 2390 if (CheckVectorCast(TyR, castExpr->getType(), castType)) 2391 return true; 2392 } else if (castType->isVectorType()) { 2393 if (CheckVectorCast(TyR, castType, castExpr->getType())) 2394 return true; 2395 } else if (getLangOptions().ObjC1 && isa<ObjCSuperExpr>(castExpr)) { 2396 return Diag(castExpr->getLocStart(), diag::err_illegal_super_cast) << TyR; 2397 } 2398 return false; 2399} 2400 2401bool Sema::CheckVectorCast(SourceRange R, QualType VectorTy, QualType Ty) { 2402 assert(VectorTy->isVectorType() && "Not a vector type!"); 2403 2404 if (Ty->isVectorType() || Ty->isIntegerType()) { 2405 if (Context.getTypeSize(VectorTy) != Context.getTypeSize(Ty)) 2406 return Diag(R.getBegin(), 2407 Ty->isVectorType() ? 2408 diag::err_invalid_conversion_between_vectors : 2409 diag::err_invalid_conversion_between_vector_and_integer) 2410 << VectorTy << Ty << R; 2411 } else 2412 return Diag(R.getBegin(), 2413 diag::err_invalid_conversion_between_vector_and_scalar) 2414 << VectorTy << Ty << R; 2415 2416 return false; 2417} 2418 2419Action::OwningExprResult 2420Sema::ActOnCastExpr(SourceLocation LParenLoc, TypeTy *Ty, 2421 SourceLocation RParenLoc, ExprArg Op) { 2422 assert((Ty != 0) && (Op.get() != 0) && 2423 "ActOnCastExpr(): missing type or expr"); 2424 2425 Expr *castExpr = static_cast<Expr*>(Op.release()); 2426 QualType castType = QualType::getFromOpaquePtr(Ty); 2427 2428 if (CheckCastTypes(SourceRange(LParenLoc, RParenLoc), castType, castExpr)) 2429 return ExprError(); 2430 return Owned(new (Context) CStyleCastExpr(castType, castExpr, castType, 2431 LParenLoc, RParenLoc)); 2432} 2433 2434/// Note that lhs is not null here, even if this is the gnu "x ?: y" extension. 2435/// In that case, lhs = cond. 2436/// C99 6.5.15 2437QualType Sema::CheckConditionalOperands(Expr *&Cond, Expr *&LHS, Expr *&RHS, 2438 SourceLocation QuestionLoc) { 2439 UsualUnaryConversions(Cond); 2440 UsualUnaryConversions(LHS); 2441 UsualUnaryConversions(RHS); 2442 QualType CondTy = Cond->getType(); 2443 QualType LHSTy = LHS->getType(); 2444 QualType RHSTy = RHS->getType(); 2445 2446 // first, check the condition. 2447 if (!Cond->isTypeDependent()) { 2448 if (!CondTy->isScalarType()) { // C99 6.5.15p2 2449 Diag(Cond->getLocStart(), diag::err_typecheck_cond_expect_scalar) 2450 << CondTy; 2451 return QualType(); 2452 } 2453 } 2454 2455 // Now check the two expressions. 2456 if ((LHS && LHS->isTypeDependent()) || (RHS && RHS->isTypeDependent())) 2457 return Context.DependentTy; 2458 2459 // If both operands have arithmetic type, do the usual arithmetic conversions 2460 // to find a common type: C99 6.5.15p3,5. 2461 if (LHSTy->isArithmeticType() && RHSTy->isArithmeticType()) { 2462 UsualArithmeticConversions(LHS, RHS); 2463 return LHS->getType(); 2464 } 2465 2466 // If both operands are the same structure or union type, the result is that 2467 // type. 2468 if (const RecordType *LHSRT = LHSTy->getAsRecordType()) { // C99 6.5.15p3 2469 if (const RecordType *RHSRT = RHSTy->getAsRecordType()) 2470 if (LHSRT->getDecl() == RHSRT->getDecl()) 2471 // "If both the operands have structure or union type, the result has 2472 // that type." This implies that CV qualifiers are dropped. 2473 return LHSTy.getUnqualifiedType(); 2474 } 2475 2476 // C99 6.5.15p5: "If both operands have void type, the result has void type." 2477 // The following || allows only one side to be void (a GCC-ism). 2478 if (LHSTy->isVoidType() || RHSTy->isVoidType()) { 2479 if (!LHSTy->isVoidType()) 2480 Diag(RHS->getLocStart(), diag::ext_typecheck_cond_one_void) 2481 << RHS->getSourceRange(); 2482 if (!RHSTy->isVoidType()) 2483 Diag(LHS->getLocStart(), diag::ext_typecheck_cond_one_void) 2484 << LHS->getSourceRange(); 2485 ImpCastExprToType(LHS, Context.VoidTy); 2486 ImpCastExprToType(RHS, Context.VoidTy); 2487 return Context.VoidTy; 2488 } 2489 // C99 6.5.15p6 - "if one operand is a null pointer constant, the result has 2490 // the type of the other operand." 2491 if ((LHSTy->isPointerType() || LHSTy->isBlockPointerType() || 2492 Context.isObjCObjectPointerType(LHSTy)) && 2493 RHS->isNullPointerConstant(Context)) { 2494 ImpCastExprToType(RHS, LHSTy); // promote the null to a pointer. 2495 return LHSTy; 2496 } 2497 if ((RHSTy->isPointerType() || RHSTy->isBlockPointerType() || 2498 Context.isObjCObjectPointerType(RHSTy)) && 2499 LHS->isNullPointerConstant(Context)) { 2500 ImpCastExprToType(LHS, RHSTy); // promote the null to a pointer. 2501 return RHSTy; 2502 } 2503 2504 // Handle the case where both operands are pointers before we handle null 2505 // pointer constants in case both operands are null pointer constants. 2506 if (const PointerType *LHSPT = LHSTy->getAsPointerType()) { // C99 6.5.15p3,6 2507 if (const PointerType *RHSPT = RHSTy->getAsPointerType()) { 2508 // get the "pointed to" types 2509 QualType lhptee = LHSPT->getPointeeType(); 2510 QualType rhptee = RHSPT->getPointeeType(); 2511 2512 // ignore qualifiers on void (C99 6.5.15p3, clause 6) 2513 if (lhptee->isVoidType() && 2514 rhptee->isIncompleteOrObjectType()) { 2515 // Figure out necessary qualifiers (C99 6.5.15p6) 2516 QualType destPointee=lhptee.getQualifiedType(rhptee.getCVRQualifiers()); 2517 QualType destType = Context.getPointerType(destPointee); 2518 ImpCastExprToType(LHS, destType); // add qualifiers if necessary 2519 ImpCastExprToType(RHS, destType); // promote to void* 2520 return destType; 2521 } 2522 if (rhptee->isVoidType() && lhptee->isIncompleteOrObjectType()) { 2523 QualType destPointee=rhptee.getQualifiedType(lhptee.getCVRQualifiers()); 2524 QualType destType = Context.getPointerType(destPointee); 2525 ImpCastExprToType(LHS, destType); // add qualifiers if necessary 2526 ImpCastExprToType(RHS, destType); // promote to void* 2527 return destType; 2528 } 2529 2530 if (Context.getCanonicalType(LHSTy) == Context.getCanonicalType(RHSTy)) { 2531 // Two identical pointer types are always compatible. 2532 return LHSTy; 2533 } 2534 2535 QualType compositeType = LHSTy; 2536 2537 // If either type is an Objective-C object type then check 2538 // compatibility according to Objective-C. 2539 if (Context.isObjCObjectPointerType(LHSTy) || 2540 Context.isObjCObjectPointerType(RHSTy)) { 2541 // If both operands are interfaces and either operand can be 2542 // assigned to the other, use that type as the composite 2543 // type. This allows 2544 // xxx ? (A*) a : (B*) b 2545 // where B is a subclass of A. 2546 // 2547 // Additionally, as for assignment, if either type is 'id' 2548 // allow silent coercion. Finally, if the types are 2549 // incompatible then make sure to use 'id' as the composite 2550 // type so the result is acceptable for sending messages to. 2551 2552 // FIXME: Consider unifying with 'areComparableObjCPointerTypes'. 2553 // It could return the composite type. 2554 const ObjCInterfaceType* LHSIface = lhptee->getAsObjCInterfaceType(); 2555 const ObjCInterfaceType* RHSIface = rhptee->getAsObjCInterfaceType(); 2556 if (LHSIface && RHSIface && 2557 Context.canAssignObjCInterfaces(LHSIface, RHSIface)) { 2558 compositeType = LHSTy; 2559 } else if (LHSIface && RHSIface && 2560 Context.canAssignObjCInterfaces(RHSIface, LHSIface)) { 2561 compositeType = RHSTy; 2562 } else if (Context.isObjCIdStructType(lhptee) || 2563 Context.isObjCIdStructType(rhptee)) { 2564 compositeType = Context.getObjCIdType(); 2565 } else { 2566 Diag(QuestionLoc, diag::ext_typecheck_comparison_of_distinct_pointers) 2567 << LHSTy << RHSTy 2568 << LHS->getSourceRange() << RHS->getSourceRange(); 2569 QualType incompatTy = Context.getObjCIdType(); 2570 ImpCastExprToType(LHS, incompatTy); 2571 ImpCastExprToType(RHS, incompatTy); 2572 return incompatTy; 2573 } 2574 } else if (!Context.typesAreCompatible(lhptee.getUnqualifiedType(), 2575 rhptee.getUnqualifiedType())) { 2576 Diag(QuestionLoc, diag::warn_typecheck_cond_incompatible_pointers) 2577 << LHSTy << RHSTy << LHS->getSourceRange() << RHS->getSourceRange(); 2578 // In this situation, we assume void* type. No especially good 2579 // reason, but this is what gcc does, and we do have to pick 2580 // to get a consistent AST. 2581 QualType incompatTy = Context.getPointerType(Context.VoidTy); 2582 ImpCastExprToType(LHS, incompatTy); 2583 ImpCastExprToType(RHS, incompatTy); 2584 return incompatTy; 2585 } 2586 // The pointer types are compatible. 2587 // C99 6.5.15p6: If both operands are pointers to compatible types *or* to 2588 // differently qualified versions of compatible types, the result type is 2589 // a pointer to an appropriately qualified version of the *composite* 2590 // type. 2591 // FIXME: Need to calculate the composite type. 2592 // FIXME: Need to add qualifiers 2593 ImpCastExprToType(LHS, compositeType); 2594 ImpCastExprToType(RHS, compositeType); 2595 return compositeType; 2596 } 2597 } 2598 2599 // Selection between block pointer types is ok as long as they are the same. 2600 if (LHSTy->isBlockPointerType() && RHSTy->isBlockPointerType() && 2601 Context.getCanonicalType(LHSTy) == Context.getCanonicalType(RHSTy)) 2602 return LHSTy; 2603 2604 // Need to handle "id<xx>" explicitly. Unlike "id", whose canonical type 2605 // evaluates to "struct objc_object *" (and is handled above when comparing 2606 // id with statically typed objects). 2607 if (LHSTy->isObjCQualifiedIdType() || RHSTy->isObjCQualifiedIdType()) { 2608 // GCC allows qualified id and any Objective-C type to devolve to 2609 // id. Currently localizing to here until clear this should be 2610 // part of ObjCQualifiedIdTypesAreCompatible. 2611 if (ObjCQualifiedIdTypesAreCompatible(LHSTy, RHSTy, true) || 2612 (LHSTy->isObjCQualifiedIdType() && 2613 Context.isObjCObjectPointerType(RHSTy)) || 2614 (RHSTy->isObjCQualifiedIdType() && 2615 Context.isObjCObjectPointerType(LHSTy))) { 2616 // FIXME: This is not the correct composite type. This only 2617 // happens to work because id can more or less be used anywhere, 2618 // however this may change the type of method sends. 2619 // FIXME: gcc adds some type-checking of the arguments and emits 2620 // (confusing) incompatible comparison warnings in some 2621 // cases. Investigate. 2622 QualType compositeType = Context.getObjCIdType(); 2623 ImpCastExprToType(LHS, compositeType); 2624 ImpCastExprToType(RHS, compositeType); 2625 return compositeType; 2626 } 2627 } 2628 2629 // Otherwise, the operands are not compatible. 2630 Diag(QuestionLoc, diag::err_typecheck_cond_incompatible_operands) 2631 << LHSTy << RHSTy << LHS->getSourceRange() << RHS->getSourceRange(); 2632 return QualType(); 2633} 2634 2635/// ActOnConditionalOp - Parse a ?: operation. Note that 'LHS' may be null 2636/// in the case of a the GNU conditional expr extension. 2637Action::OwningExprResult Sema::ActOnConditionalOp(SourceLocation QuestionLoc, 2638 SourceLocation ColonLoc, 2639 ExprArg Cond, ExprArg LHS, 2640 ExprArg RHS) { 2641 Expr *CondExpr = (Expr *) Cond.get(); 2642 Expr *LHSExpr = (Expr *) LHS.get(), *RHSExpr = (Expr *) RHS.get(); 2643 2644 // If this is the gnu "x ?: y" extension, analyze the types as though the LHS 2645 // was the condition. 2646 bool isLHSNull = LHSExpr == 0; 2647 if (isLHSNull) 2648 LHSExpr = CondExpr; 2649 2650 QualType result = CheckConditionalOperands(CondExpr, LHSExpr, 2651 RHSExpr, QuestionLoc); 2652 if (result.isNull()) 2653 return ExprError(); 2654 2655 Cond.release(); 2656 LHS.release(); 2657 RHS.release(); 2658 return Owned(new (Context) ConditionalOperator(CondExpr, 2659 isLHSNull ? 0 : LHSExpr, 2660 RHSExpr, result)); 2661} 2662 2663 2664// CheckPointerTypesForAssignment - This is a very tricky routine (despite 2665// being closely modeled after the C99 spec:-). The odd characteristic of this 2666// routine is it effectively iqnores the qualifiers on the top level pointee. 2667// This circumvents the usual type rules specified in 6.2.7p1 & 6.7.5.[1-3]. 2668// FIXME: add a couple examples in this comment. 2669Sema::AssignConvertType 2670Sema::CheckPointerTypesForAssignment(QualType lhsType, QualType rhsType) { 2671 QualType lhptee, rhptee; 2672 2673 // get the "pointed to" type (ignoring qualifiers at the top level) 2674 lhptee = lhsType->getAsPointerType()->getPointeeType(); 2675 rhptee = rhsType->getAsPointerType()->getPointeeType(); 2676 2677 // make sure we operate on the canonical type 2678 lhptee = Context.getCanonicalType(lhptee); 2679 rhptee = Context.getCanonicalType(rhptee); 2680 2681 AssignConvertType ConvTy = Compatible; 2682 2683 // C99 6.5.16.1p1: This following citation is common to constraints 2684 // 3 & 4 (below). ...and the type *pointed to* by the left has all the 2685 // qualifiers of the type *pointed to* by the right; 2686 // FIXME: Handle ExtQualType 2687 if (!lhptee.isAtLeastAsQualifiedAs(rhptee)) 2688 ConvTy = CompatiblePointerDiscardsQualifiers; 2689 2690 // C99 6.5.16.1p1 (constraint 4): If one operand is a pointer to an object or 2691 // incomplete type and the other is a pointer to a qualified or unqualified 2692 // version of void... 2693 if (lhptee->isVoidType()) { 2694 if (rhptee->isIncompleteOrObjectType()) 2695 return ConvTy; 2696 2697 // As an extension, we allow cast to/from void* to function pointer. 2698 assert(rhptee->isFunctionType()); 2699 return FunctionVoidPointer; 2700 } 2701 2702 if (rhptee->isVoidType()) { 2703 if (lhptee->isIncompleteOrObjectType()) 2704 return ConvTy; 2705 2706 // As an extension, we allow cast to/from void* to function pointer. 2707 assert(lhptee->isFunctionType()); 2708 return FunctionVoidPointer; 2709 } 2710 // C99 6.5.16.1p1 (constraint 3): both operands are pointers to qualified or 2711 // unqualified versions of compatible types, ... 2712 if (!Context.typesAreCompatible(lhptee.getUnqualifiedType(), 2713 rhptee.getUnqualifiedType())) 2714 return IncompatiblePointer; // this "trumps" PointerAssignDiscardsQualifiers 2715 return ConvTy; 2716} 2717 2718/// CheckBlockPointerTypesForAssignment - This routine determines whether two 2719/// block pointer types are compatible or whether a block and normal pointer 2720/// are compatible. It is more restrict than comparing two function pointer 2721// types. 2722Sema::AssignConvertType 2723Sema::CheckBlockPointerTypesForAssignment(QualType lhsType, 2724 QualType rhsType) { 2725 QualType lhptee, rhptee; 2726 2727 // get the "pointed to" type (ignoring qualifiers at the top level) 2728 lhptee = lhsType->getAsBlockPointerType()->getPointeeType(); 2729 rhptee = rhsType->getAsBlockPointerType()->getPointeeType(); 2730 2731 // make sure we operate on the canonical type 2732 lhptee = Context.getCanonicalType(lhptee); 2733 rhptee = Context.getCanonicalType(rhptee); 2734 2735 AssignConvertType ConvTy = Compatible; 2736 2737 // For blocks we enforce that qualifiers are identical. 2738 if (lhptee.getCVRQualifiers() != rhptee.getCVRQualifiers()) 2739 ConvTy = CompatiblePointerDiscardsQualifiers; 2740 2741 if (!Context.typesAreBlockCompatible(lhptee, rhptee)) 2742 return IncompatibleBlockPointer; 2743 return ConvTy; 2744} 2745 2746/// CheckAssignmentConstraints (C99 6.5.16) - This routine currently 2747/// has code to accommodate several GCC extensions when type checking 2748/// pointers. Here are some objectionable examples that GCC considers warnings: 2749/// 2750/// int a, *pint; 2751/// short *pshort; 2752/// struct foo *pfoo; 2753/// 2754/// pint = pshort; // warning: assignment from incompatible pointer type 2755/// a = pint; // warning: assignment makes integer from pointer without a cast 2756/// pint = a; // warning: assignment makes pointer from integer without a cast 2757/// pint = pfoo; // warning: assignment from incompatible pointer type 2758/// 2759/// As a result, the code for dealing with pointers is more complex than the 2760/// C99 spec dictates. 2761/// 2762Sema::AssignConvertType 2763Sema::CheckAssignmentConstraints(QualType lhsType, QualType rhsType) { 2764 // Get canonical types. We're not formatting these types, just comparing 2765 // them. 2766 lhsType = Context.getCanonicalType(lhsType).getUnqualifiedType(); 2767 rhsType = Context.getCanonicalType(rhsType).getUnqualifiedType(); 2768 2769 if (lhsType == rhsType) 2770 return Compatible; // Common case: fast path an exact match. 2771 2772 // If the left-hand side is a reference type, then we are in a 2773 // (rare!) case where we've allowed the use of references in C, 2774 // e.g., as a parameter type in a built-in function. In this case, 2775 // just make sure that the type referenced is compatible with the 2776 // right-hand side type. The caller is responsible for adjusting 2777 // lhsType so that the resulting expression does not have reference 2778 // type. 2779 if (const ReferenceType *lhsTypeRef = lhsType->getAsReferenceType()) { 2780 if (Context.typesAreCompatible(lhsTypeRef->getPointeeType(), rhsType)) 2781 return Compatible; 2782 return Incompatible; 2783 } 2784 2785 if (lhsType->isObjCQualifiedIdType() || rhsType->isObjCQualifiedIdType()) { 2786 if (ObjCQualifiedIdTypesAreCompatible(lhsType, rhsType, false)) 2787 return Compatible; 2788 // Relax integer conversions like we do for pointers below. 2789 if (rhsType->isIntegerType()) 2790 return IntToPointer; 2791 if (lhsType->isIntegerType()) 2792 return PointerToInt; 2793 return IncompatibleObjCQualifiedId; 2794 } 2795 2796 if (lhsType->isVectorType() || rhsType->isVectorType()) { 2797 // For ExtVector, allow vector splats; float -> <n x float> 2798 if (const ExtVectorType *LV = lhsType->getAsExtVectorType()) 2799 if (LV->getElementType() == rhsType) 2800 return Compatible; 2801 2802 // If we are allowing lax vector conversions, and LHS and RHS are both 2803 // vectors, the total size only needs to be the same. This is a bitcast; 2804 // no bits are changed but the result type is different. 2805 if (getLangOptions().LaxVectorConversions && 2806 lhsType->isVectorType() && rhsType->isVectorType()) { 2807 if (Context.getTypeSize(lhsType) == Context.getTypeSize(rhsType)) 2808 return IncompatibleVectors; 2809 } 2810 return Incompatible; 2811 } 2812 2813 if (lhsType->isArithmeticType() && rhsType->isArithmeticType()) 2814 return Compatible; 2815 2816 if (isa<PointerType>(lhsType)) { 2817 if (rhsType->isIntegerType()) 2818 return IntToPointer; 2819 2820 if (isa<PointerType>(rhsType)) 2821 return CheckPointerTypesForAssignment(lhsType, rhsType); 2822 2823 if (rhsType->getAsBlockPointerType()) { 2824 if (lhsType->getAsPointerType()->getPointeeType()->isVoidType()) 2825 return Compatible; 2826 2827 // Treat block pointers as objects. 2828 if (getLangOptions().ObjC1 && 2829 lhsType == Context.getCanonicalType(Context.getObjCIdType())) 2830 return Compatible; 2831 } 2832 return Incompatible; 2833 } 2834 2835 if (isa<BlockPointerType>(lhsType)) { 2836 if (rhsType->isIntegerType()) 2837 return IntToBlockPointer; 2838 2839 // Treat block pointers as objects. 2840 if (getLangOptions().ObjC1 && 2841 rhsType == Context.getCanonicalType(Context.getObjCIdType())) 2842 return Compatible; 2843 2844 if (rhsType->isBlockPointerType()) 2845 return CheckBlockPointerTypesForAssignment(lhsType, rhsType); 2846 2847 if (const PointerType *RHSPT = rhsType->getAsPointerType()) { 2848 if (RHSPT->getPointeeType()->isVoidType()) 2849 return Compatible; 2850 } 2851 return Incompatible; 2852 } 2853 2854 if (isa<PointerType>(rhsType)) { 2855 // C99 6.5.16.1p1: the left operand is _Bool and the right is a pointer. 2856 if (lhsType == Context.BoolTy) 2857 return Compatible; 2858 2859 if (lhsType->isIntegerType()) 2860 return PointerToInt; 2861 2862 if (isa<PointerType>(lhsType)) 2863 return CheckPointerTypesForAssignment(lhsType, rhsType); 2864 2865 if (isa<BlockPointerType>(lhsType) && 2866 rhsType->getAsPointerType()->getPointeeType()->isVoidType()) 2867 return Compatible; 2868 return Incompatible; 2869 } 2870 2871 if (isa<TagType>(lhsType) && isa<TagType>(rhsType)) { 2872 if (Context.typesAreCompatible(lhsType, rhsType)) 2873 return Compatible; 2874 } 2875 return Incompatible; 2876} 2877 2878Sema::AssignConvertType 2879Sema::CheckSingleAssignmentConstraints(QualType lhsType, Expr *&rExpr) { 2880 if (getLangOptions().CPlusPlus) { 2881 if (!lhsType->isRecordType()) { 2882 // C++ 5.17p3: If the left operand is not of class type, the 2883 // expression is implicitly converted (C++ 4) to the 2884 // cv-unqualified type of the left operand. 2885 if (PerformImplicitConversion(rExpr, lhsType.getUnqualifiedType(), 2886 "assigning")) 2887 return Incompatible; 2888 else 2889 return Compatible; 2890 } 2891 2892 // FIXME: Currently, we fall through and treat C++ classes like C 2893 // structures. 2894 } 2895 2896 // C99 6.5.16.1p1: the left operand is a pointer and the right is 2897 // a null pointer constant. 2898 if ((lhsType->isPointerType() || 2899 lhsType->isObjCQualifiedIdType() || 2900 lhsType->isBlockPointerType()) 2901 && rExpr->isNullPointerConstant(Context)) { 2902 ImpCastExprToType(rExpr, lhsType); 2903 return Compatible; 2904 } 2905 2906 // This check seems unnatural, however it is necessary to ensure the proper 2907 // conversion of functions/arrays. If the conversion were done for all 2908 // DeclExpr's (created by ActOnIdentifierExpr), it would mess up the unary 2909 // expressions that surpress this implicit conversion (&, sizeof). 2910 // 2911 // Suppress this for references: C++ 8.5.3p5. 2912 if (!lhsType->isReferenceType()) 2913 DefaultFunctionArrayConversion(rExpr); 2914 2915 Sema::AssignConvertType result = 2916 CheckAssignmentConstraints(lhsType, rExpr->getType()); 2917 2918 // C99 6.5.16.1p2: The value of the right operand is converted to the 2919 // type of the assignment expression. 2920 // CheckAssignmentConstraints allows the left-hand side to be a reference, 2921 // so that we can use references in built-in functions even in C. 2922 // The getNonReferenceType() call makes sure that the resulting expression 2923 // does not have reference type. 2924 if (rExpr->getType() != lhsType) 2925 ImpCastExprToType(rExpr, lhsType.getNonReferenceType()); 2926 return result; 2927} 2928 2929Sema::AssignConvertType 2930Sema::CheckCompoundAssignmentConstraints(QualType lhsType, QualType rhsType) { 2931 return CheckAssignmentConstraints(lhsType, rhsType); 2932} 2933 2934QualType Sema::InvalidOperands(SourceLocation Loc, Expr *&lex, Expr *&rex) { 2935 Diag(Loc, diag::err_typecheck_invalid_operands) 2936 << lex->getType() << rex->getType() 2937 << lex->getSourceRange() << rex->getSourceRange(); 2938 return QualType(); 2939} 2940 2941inline QualType Sema::CheckVectorOperands(SourceLocation Loc, Expr *&lex, 2942 Expr *&rex) { 2943 // For conversion purposes, we ignore any qualifiers. 2944 // For example, "const float" and "float" are equivalent. 2945 QualType lhsType = 2946 Context.getCanonicalType(lex->getType()).getUnqualifiedType(); 2947 QualType rhsType = 2948 Context.getCanonicalType(rex->getType()).getUnqualifiedType(); 2949 2950 // If the vector types are identical, return. 2951 if (lhsType == rhsType) 2952 return lhsType; 2953 2954 // Handle the case of a vector & extvector type of the same size and element 2955 // type. It would be nice if we only had one vector type someday. 2956 if (getLangOptions().LaxVectorConversions) { 2957 // FIXME: Should we warn here? 2958 if (const VectorType *LV = lhsType->getAsVectorType()) { 2959 if (const VectorType *RV = rhsType->getAsVectorType()) 2960 if (LV->getElementType() == RV->getElementType() && 2961 LV->getNumElements() == RV->getNumElements()) { 2962 return lhsType->isExtVectorType() ? lhsType : rhsType; 2963 } 2964 } 2965 } 2966 2967 // If the lhs is an extended vector and the rhs is a scalar of the same type 2968 // or a literal, promote the rhs to the vector type. 2969 if (const ExtVectorType *V = lhsType->getAsExtVectorType()) { 2970 QualType eltType = V->getElementType(); 2971 2972 if ((eltType->getAsBuiltinType() == rhsType->getAsBuiltinType()) || 2973 (eltType->isIntegerType() && isa<IntegerLiteral>(rex)) || 2974 (eltType->isFloatingType() && isa<FloatingLiteral>(rex))) { 2975 ImpCastExprToType(rex, lhsType); 2976 return lhsType; 2977 } 2978 } 2979 2980 // If the rhs is an extended vector and the lhs is a scalar of the same type, 2981 // promote the lhs to the vector type. 2982 if (const ExtVectorType *V = rhsType->getAsExtVectorType()) { 2983 QualType eltType = V->getElementType(); 2984 2985 if ((eltType->getAsBuiltinType() == lhsType->getAsBuiltinType()) || 2986 (eltType->isIntegerType() && isa<IntegerLiteral>(lex)) || 2987 (eltType->isFloatingType() && isa<FloatingLiteral>(lex))) { 2988 ImpCastExprToType(lex, rhsType); 2989 return rhsType; 2990 } 2991 } 2992 2993 // You cannot convert between vector values of different size. 2994 Diag(Loc, diag::err_typecheck_vector_not_convertable) 2995 << lex->getType() << rex->getType() 2996 << lex->getSourceRange() << rex->getSourceRange(); 2997 return QualType(); 2998} 2999 3000inline QualType Sema::CheckMultiplyDivideOperands( 3001 Expr *&lex, Expr *&rex, SourceLocation Loc, bool isCompAssign) 3002{ 3003 if (lex->getType()->isVectorType() || rex->getType()->isVectorType()) 3004 return CheckVectorOperands(Loc, lex, rex); 3005 3006 QualType compType = UsualArithmeticConversions(lex, rex, isCompAssign); 3007 3008 if (lex->getType()->isArithmeticType() && rex->getType()->isArithmeticType()) 3009 return compType; 3010 return InvalidOperands(Loc, lex, rex); 3011} 3012 3013inline QualType Sema::CheckRemainderOperands( 3014 Expr *&lex, Expr *&rex, SourceLocation Loc, bool isCompAssign) 3015{ 3016 if (lex->getType()->isVectorType() || rex->getType()->isVectorType()) { 3017 if (lex->getType()->isIntegerType() && rex->getType()->isIntegerType()) 3018 return CheckVectorOperands(Loc, lex, rex); 3019 return InvalidOperands(Loc, lex, rex); 3020 } 3021 3022 QualType compType = UsualArithmeticConversions(lex, rex, isCompAssign); 3023 3024 if (lex->getType()->isIntegerType() && rex->getType()->isIntegerType()) 3025 return compType; 3026 return InvalidOperands(Loc, lex, rex); 3027} 3028 3029inline QualType Sema::CheckAdditionOperands( // C99 6.5.6 3030 Expr *&lex, Expr *&rex, SourceLocation Loc, bool isCompAssign) 3031{ 3032 if (lex->getType()->isVectorType() || rex->getType()->isVectorType()) 3033 return CheckVectorOperands(Loc, lex, rex); 3034 3035 QualType compType = UsualArithmeticConversions(lex, rex, isCompAssign); 3036 3037 // handle the common case first (both operands are arithmetic). 3038 if (lex->getType()->isArithmeticType() && rex->getType()->isArithmeticType()) 3039 return compType; 3040 3041 // Put any potential pointer into PExp 3042 Expr* PExp = lex, *IExp = rex; 3043 if (IExp->getType()->isPointerType()) 3044 std::swap(PExp, IExp); 3045 3046 if (const PointerType* PTy = PExp->getType()->getAsPointerType()) { 3047 if (IExp->getType()->isIntegerType()) { 3048 // Check for arithmetic on pointers to incomplete types 3049 if (!PTy->getPointeeType()->isObjectType()) { 3050 if (PTy->getPointeeType()->isVoidType()) { 3051 if (getLangOptions().CPlusPlus) { 3052 Diag(Loc, diag::err_typecheck_pointer_arith_void_type) 3053 << lex->getSourceRange() << rex->getSourceRange(); 3054 return QualType(); 3055 } 3056 3057 // GNU extension: arithmetic on pointer to void 3058 Diag(Loc, diag::ext_gnu_void_ptr) 3059 << lex->getSourceRange() << rex->getSourceRange(); 3060 } else if (PTy->getPointeeType()->isFunctionType()) { 3061 if (getLangOptions().CPlusPlus) { 3062 Diag(Loc, diag::err_typecheck_pointer_arith_function_type) 3063 << lex->getType() << lex->getSourceRange(); 3064 return QualType(); 3065 } 3066 3067 // GNU extension: arithmetic on pointer to function 3068 Diag(Loc, diag::ext_gnu_ptr_func_arith) 3069 << lex->getType() << lex->getSourceRange(); 3070 } else { 3071 RequireCompleteType(Loc, PTy->getPointeeType(), 3072 diag::err_typecheck_arithmetic_incomplete_type, 3073 lex->getSourceRange(), SourceRange(), 3074 lex->getType()); 3075 return QualType(); 3076 } 3077 } 3078 return PExp->getType(); 3079 } 3080 } 3081 3082 return InvalidOperands(Loc, lex, rex); 3083} 3084 3085// C99 6.5.6 3086QualType Sema::CheckSubtractionOperands(Expr *&lex, Expr *&rex, 3087 SourceLocation Loc, bool isCompAssign) { 3088 if (lex->getType()->isVectorType() || rex->getType()->isVectorType()) 3089 return CheckVectorOperands(Loc, lex, rex); 3090 3091 QualType compType = UsualArithmeticConversions(lex, rex, isCompAssign); 3092 3093 // Enforce type constraints: C99 6.5.6p3. 3094 3095 // Handle the common case first (both operands are arithmetic). 3096 if (lex->getType()->isArithmeticType() && rex->getType()->isArithmeticType()) 3097 return compType; 3098 3099 // Either ptr - int or ptr - ptr. 3100 if (const PointerType *LHSPTy = lex->getType()->getAsPointerType()) { 3101 QualType lpointee = LHSPTy->getPointeeType(); 3102 3103 // The LHS must be an object type, not incomplete, function, etc. 3104 if (!lpointee->isObjectType()) { 3105 // Handle the GNU void* extension. 3106 if (lpointee->isVoidType()) { 3107 Diag(Loc, diag::ext_gnu_void_ptr) 3108 << lex->getSourceRange() << rex->getSourceRange(); 3109 } else if (lpointee->isFunctionType()) { 3110 if (getLangOptions().CPlusPlus) { 3111 Diag(Loc, diag::err_typecheck_pointer_arith_function_type) 3112 << lex->getType() << lex->getSourceRange(); 3113 return QualType(); 3114 } 3115 3116 // GNU extension: arithmetic on pointer to function 3117 Diag(Loc, diag::ext_gnu_ptr_func_arith) 3118 << lex->getType() << lex->getSourceRange(); 3119 } else { 3120 Diag(Loc, diag::err_typecheck_sub_ptr_object) 3121 << lex->getType() << lex->getSourceRange(); 3122 return QualType(); 3123 } 3124 } 3125 3126 // The result type of a pointer-int computation is the pointer type. 3127 if (rex->getType()->isIntegerType()) 3128 return lex->getType(); 3129 3130 // Handle pointer-pointer subtractions. 3131 if (const PointerType *RHSPTy = rex->getType()->getAsPointerType()) { 3132 QualType rpointee = RHSPTy->getPointeeType(); 3133 3134 // RHS must be an object type, unless void (GNU). 3135 if (!rpointee->isObjectType()) { 3136 // Handle the GNU void* extension. 3137 if (rpointee->isVoidType()) { 3138 if (!lpointee->isVoidType()) 3139 Diag(Loc, diag::ext_gnu_void_ptr) 3140 << lex->getSourceRange() << rex->getSourceRange(); 3141 } else if (rpointee->isFunctionType()) { 3142 if (getLangOptions().CPlusPlus) { 3143 Diag(Loc, diag::err_typecheck_pointer_arith_function_type) 3144 << rex->getType() << rex->getSourceRange(); 3145 return QualType(); 3146 } 3147 3148 // GNU extension: arithmetic on pointer to function 3149 if (!lpointee->isFunctionType()) 3150 Diag(Loc, diag::ext_gnu_ptr_func_arith) 3151 << lex->getType() << lex->getSourceRange(); 3152 } else { 3153 Diag(Loc, diag::err_typecheck_sub_ptr_object) 3154 << rex->getType() << rex->getSourceRange(); 3155 return QualType(); 3156 } 3157 } 3158 3159 // Pointee types must be compatible. 3160 if (!Context.typesAreCompatible( 3161 Context.getCanonicalType(lpointee).getUnqualifiedType(), 3162 Context.getCanonicalType(rpointee).getUnqualifiedType())) { 3163 Diag(Loc, diag::err_typecheck_sub_ptr_compatible) 3164 << lex->getType() << rex->getType() 3165 << lex->getSourceRange() << rex->getSourceRange(); 3166 return QualType(); 3167 } 3168 3169 return Context.getPointerDiffType(); 3170 } 3171 } 3172 3173 return InvalidOperands(Loc, lex, rex); 3174} 3175 3176// C99 6.5.7 3177QualType Sema::CheckShiftOperands(Expr *&lex, Expr *&rex, SourceLocation Loc, 3178 bool isCompAssign) { 3179 // C99 6.5.7p2: Each of the operands shall have integer type. 3180 if (!lex->getType()->isIntegerType() || !rex->getType()->isIntegerType()) 3181 return InvalidOperands(Loc, lex, rex); 3182 3183 // Shifts don't perform usual arithmetic conversions, they just do integer 3184 // promotions on each operand. C99 6.5.7p3 3185 if (!isCompAssign) 3186 UsualUnaryConversions(lex); 3187 UsualUnaryConversions(rex); 3188 3189 // "The type of the result is that of the promoted left operand." 3190 return lex->getType(); 3191} 3192 3193// C99 6.5.8 3194QualType Sema::CheckCompareOperands(Expr *&lex, Expr *&rex, SourceLocation Loc, 3195 bool isRelational) { 3196 if (lex->getType()->isVectorType() || rex->getType()->isVectorType()) 3197 return CheckVectorCompareOperands(lex, rex, Loc, isRelational); 3198 3199 // C99 6.5.8p3 / C99 6.5.9p4 3200 if (lex->getType()->isArithmeticType() && rex->getType()->isArithmeticType()) 3201 UsualArithmeticConversions(lex, rex); 3202 else { 3203 UsualUnaryConversions(lex); 3204 UsualUnaryConversions(rex); 3205 } 3206 QualType lType = lex->getType(); 3207 QualType rType = rex->getType(); 3208 3209 if (!lType->isFloatingType()) { 3210 // For non-floating point types, check for self-comparisons of the form 3211 // x == x, x != x, x < x, etc. These always evaluate to a constant, and 3212 // often indicate logic errors in the program. 3213 Expr *LHSStripped = lex->IgnoreParens(); 3214 Expr *RHSStripped = rex->IgnoreParens(); 3215 if (DeclRefExpr* DRL = dyn_cast<DeclRefExpr>(LHSStripped)) 3216 if (DeclRefExpr* DRR = dyn_cast<DeclRefExpr>(RHSStripped)) 3217 if (DRL->getDecl() == DRR->getDecl()) 3218 Diag(Loc, diag::warn_selfcomparison); 3219 3220 if (isa<CastExpr>(LHSStripped)) 3221 LHSStripped = LHSStripped->IgnoreParenCasts(); 3222 if (isa<CastExpr>(RHSStripped)) 3223 RHSStripped = RHSStripped->IgnoreParenCasts(); 3224 3225 // Warn about comparisons against a string constant (unless the other 3226 // operand is null), the user probably wants strcmp. 3227 if ((isa<StringLiteral>(LHSStripped) || isa<ObjCEncodeExpr>(LHSStripped)) && 3228 !RHSStripped->isNullPointerConstant(Context)) 3229 Diag(Loc, diag::warn_stringcompare) << lex->getSourceRange(); 3230 else if ((isa<StringLiteral>(RHSStripped) || 3231 isa<ObjCEncodeExpr>(RHSStripped)) && 3232 !LHSStripped->isNullPointerConstant(Context)) 3233 Diag(Loc, diag::warn_stringcompare) << rex->getSourceRange(); 3234 } 3235 3236 // The result of comparisons is 'bool' in C++, 'int' in C. 3237 QualType ResultTy = getLangOptions().CPlusPlus? Context.BoolTy :Context.IntTy; 3238 3239 if (isRelational) { 3240 if (lType->isRealType() && rType->isRealType()) 3241 return ResultTy; 3242 } else { 3243 // Check for comparisons of floating point operands using != and ==. 3244 if (lType->isFloatingType()) { 3245 assert(rType->isFloatingType()); 3246 CheckFloatComparison(Loc,lex,rex); 3247 } 3248 3249 if (lType->isArithmeticType() && rType->isArithmeticType()) 3250 return ResultTy; 3251 } 3252 3253 bool LHSIsNull = lex->isNullPointerConstant(Context); 3254 bool RHSIsNull = rex->isNullPointerConstant(Context); 3255 3256 // All of the following pointer related warnings are GCC extensions, except 3257 // when handling null pointer constants. One day, we can consider making them 3258 // errors (when -pedantic-errors is enabled). 3259 if (lType->isPointerType() && rType->isPointerType()) { // C99 6.5.8p2 3260 QualType LCanPointeeTy = 3261 Context.getCanonicalType(lType->getAsPointerType()->getPointeeType()); 3262 QualType RCanPointeeTy = 3263 Context.getCanonicalType(rType->getAsPointerType()->getPointeeType()); 3264 3265 if (!LHSIsNull && !RHSIsNull && // C99 6.5.9p2 3266 !LCanPointeeTy->isVoidType() && !RCanPointeeTy->isVoidType() && 3267 !Context.typesAreCompatible(LCanPointeeTy.getUnqualifiedType(), 3268 RCanPointeeTy.getUnqualifiedType()) && 3269 !Context.areComparableObjCPointerTypes(lType, rType)) { 3270 Diag(Loc, diag::ext_typecheck_comparison_of_distinct_pointers) 3271 << lType << rType << lex->getSourceRange() << rex->getSourceRange(); 3272 } 3273 ImpCastExprToType(rex, lType); // promote the pointer to pointer 3274 return ResultTy; 3275 } 3276 // Handle block pointer types. 3277 if (lType->isBlockPointerType() && rType->isBlockPointerType()) { 3278 QualType lpointee = lType->getAsBlockPointerType()->getPointeeType(); 3279 QualType rpointee = rType->getAsBlockPointerType()->getPointeeType(); 3280 3281 if (!LHSIsNull && !RHSIsNull && 3282 !Context.typesAreBlockCompatible(lpointee, rpointee)) { 3283 Diag(Loc, diag::err_typecheck_comparison_of_distinct_blocks) 3284 << lType << rType << lex->getSourceRange() << rex->getSourceRange(); 3285 } 3286 ImpCastExprToType(rex, lType); // promote the pointer to pointer 3287 return ResultTy; 3288 } 3289 // Allow block pointers to be compared with null pointer constants. 3290 if ((lType->isBlockPointerType() && rType->isPointerType()) || 3291 (lType->isPointerType() && rType->isBlockPointerType())) { 3292 if (!LHSIsNull && !RHSIsNull) { 3293 Diag(Loc, diag::err_typecheck_comparison_of_distinct_blocks) 3294 << lType << rType << lex->getSourceRange() << rex->getSourceRange(); 3295 } 3296 ImpCastExprToType(rex, lType); // promote the pointer to pointer 3297 return ResultTy; 3298 } 3299 3300 if ((lType->isObjCQualifiedIdType() || rType->isObjCQualifiedIdType())) { 3301 if (lType->isPointerType() || rType->isPointerType()) { 3302 const PointerType *LPT = lType->getAsPointerType(); 3303 const PointerType *RPT = rType->getAsPointerType(); 3304 bool LPtrToVoid = LPT ? 3305 Context.getCanonicalType(LPT->getPointeeType())->isVoidType() : false; 3306 bool RPtrToVoid = RPT ? 3307 Context.getCanonicalType(RPT->getPointeeType())->isVoidType() : false; 3308 3309 if (!LPtrToVoid && !RPtrToVoid && 3310 !Context.typesAreCompatible(lType, rType)) { 3311 Diag(Loc, diag::ext_typecheck_comparison_of_distinct_pointers) 3312 << lType << rType << lex->getSourceRange() << rex->getSourceRange(); 3313 ImpCastExprToType(rex, lType); 3314 return ResultTy; 3315 } 3316 ImpCastExprToType(rex, lType); 3317 return ResultTy; 3318 } 3319 if (ObjCQualifiedIdTypesAreCompatible(lType, rType, true)) { 3320 ImpCastExprToType(rex, lType); 3321 return ResultTy; 3322 } else { 3323 if ((lType->isObjCQualifiedIdType() && rType->isObjCQualifiedIdType())) { 3324 Diag(Loc, diag::warn_incompatible_qualified_id_operands) 3325 << lType << rType << lex->getSourceRange() << rex->getSourceRange(); 3326 ImpCastExprToType(rex, lType); 3327 return ResultTy; 3328 } 3329 } 3330 } 3331 if ((lType->isPointerType() || lType->isObjCQualifiedIdType()) && 3332 rType->isIntegerType()) { 3333 if (!RHSIsNull) 3334 Diag(Loc, diag::ext_typecheck_comparison_of_pointer_integer) 3335 << lType << rType << lex->getSourceRange() << rex->getSourceRange(); 3336 ImpCastExprToType(rex, lType); // promote the integer to pointer 3337 return ResultTy; 3338 } 3339 if (lType->isIntegerType() && 3340 (rType->isPointerType() || rType->isObjCQualifiedIdType())) { 3341 if (!LHSIsNull) 3342 Diag(Loc, diag::ext_typecheck_comparison_of_pointer_integer) 3343 << lType << rType << lex->getSourceRange() << rex->getSourceRange(); 3344 ImpCastExprToType(lex, rType); // promote the integer to pointer 3345 return ResultTy; 3346 } 3347 // Handle block pointers. 3348 if (lType->isBlockPointerType() && rType->isIntegerType()) { 3349 if (!RHSIsNull) 3350 Diag(Loc, diag::ext_typecheck_comparison_of_pointer_integer) 3351 << lType << rType << lex->getSourceRange() << rex->getSourceRange(); 3352 ImpCastExprToType(rex, lType); // promote the integer to pointer 3353 return ResultTy; 3354 } 3355 if (lType->isIntegerType() && rType->isBlockPointerType()) { 3356 if (!LHSIsNull) 3357 Diag(Loc, diag::ext_typecheck_comparison_of_pointer_integer) 3358 << lType << rType << lex->getSourceRange() << rex->getSourceRange(); 3359 ImpCastExprToType(lex, rType); // promote the integer to pointer 3360 return ResultTy; 3361 } 3362 return InvalidOperands(Loc, lex, rex); 3363} 3364 3365/// CheckVectorCompareOperands - vector comparisons are a clang extension that 3366/// operates on extended vector types. Instead of producing an IntTy result, 3367/// like a scalar comparison, a vector comparison produces a vector of integer 3368/// types. 3369QualType Sema::CheckVectorCompareOperands(Expr *&lex, Expr *&rex, 3370 SourceLocation Loc, 3371 bool isRelational) { 3372 // Check to make sure we're operating on vectors of the same type and width, 3373 // Allowing one side to be a scalar of element type. 3374 QualType vType = CheckVectorOperands(Loc, lex, rex); 3375 if (vType.isNull()) 3376 return vType; 3377 3378 QualType lType = lex->getType(); 3379 QualType rType = rex->getType(); 3380 3381 // For non-floating point types, check for self-comparisons of the form 3382 // x == x, x != x, x < x, etc. These always evaluate to a constant, and 3383 // often indicate logic errors in the program. 3384 if (!lType->isFloatingType()) { 3385 if (DeclRefExpr* DRL = dyn_cast<DeclRefExpr>(lex->IgnoreParens())) 3386 if (DeclRefExpr* DRR = dyn_cast<DeclRefExpr>(rex->IgnoreParens())) 3387 if (DRL->getDecl() == DRR->getDecl()) 3388 Diag(Loc, diag::warn_selfcomparison); 3389 } 3390 3391 // Check for comparisons of floating point operands using != and ==. 3392 if (!isRelational && lType->isFloatingType()) { 3393 assert (rType->isFloatingType()); 3394 CheckFloatComparison(Loc,lex,rex); 3395 } 3396 3397 // Return the type for the comparison, which is the same as vector type for 3398 // integer vectors, or an integer type of identical size and number of 3399 // elements for floating point vectors. 3400 if (lType->isIntegerType()) 3401 return lType; 3402 3403 const VectorType *VTy = lType->getAsVectorType(); 3404 unsigned TypeSize = Context.getTypeSize(VTy->getElementType()); 3405 if (TypeSize == Context.getTypeSize(Context.IntTy)) 3406 return Context.getExtVectorType(Context.IntTy, VTy->getNumElements()); 3407 else if (TypeSize == Context.getTypeSize(Context.LongTy)) 3408 return Context.getExtVectorType(Context.LongTy, VTy->getNumElements()); 3409 3410 assert(TypeSize == Context.getTypeSize(Context.LongLongTy) && 3411 "Unhandled vector element size in vector compare"); 3412 return Context.getExtVectorType(Context.LongLongTy, VTy->getNumElements()); 3413} 3414 3415inline QualType Sema::CheckBitwiseOperands( 3416 Expr *&lex, Expr *&rex, SourceLocation Loc, bool isCompAssign) 3417{ 3418 if (lex->getType()->isVectorType() || rex->getType()->isVectorType()) 3419 return CheckVectorOperands(Loc, lex, rex); 3420 3421 QualType compType = UsualArithmeticConversions(lex, rex, isCompAssign); 3422 3423 if (lex->getType()->isIntegerType() && rex->getType()->isIntegerType()) 3424 return compType; 3425 return InvalidOperands(Loc, lex, rex); 3426} 3427 3428inline QualType Sema::CheckLogicalOperands( // C99 6.5.[13,14] 3429 Expr *&lex, Expr *&rex, SourceLocation Loc) 3430{ 3431 UsualUnaryConversions(lex); 3432 UsualUnaryConversions(rex); 3433 3434 if (lex->getType()->isScalarType() && rex->getType()->isScalarType()) 3435 return Context.IntTy; 3436 return InvalidOperands(Loc, lex, rex); 3437} 3438 3439/// IsReadonlyProperty - Verify that otherwise a valid l-value expression 3440/// is a read-only property; return true if so. A readonly property expression 3441/// depends on various declarations and thus must be treated specially. 3442/// 3443static bool IsReadonlyProperty(Expr *E, Sema &S) 3444{ 3445 if (E->getStmtClass() == Expr::ObjCPropertyRefExprClass) { 3446 const ObjCPropertyRefExpr* PropExpr = cast<ObjCPropertyRefExpr>(E); 3447 if (ObjCPropertyDecl *PDecl = PropExpr->getProperty()) { 3448 QualType BaseType = PropExpr->getBase()->getType(); 3449 if (const PointerType *PTy = BaseType->getAsPointerType()) 3450 if (const ObjCInterfaceType *IFTy = 3451 PTy->getPointeeType()->getAsObjCInterfaceType()) 3452 if (ObjCInterfaceDecl *IFace = IFTy->getDecl()) 3453 if (S.isPropertyReadonly(PDecl, IFace)) 3454 return true; 3455 } 3456 } 3457 return false; 3458} 3459 3460/// CheckForModifiableLvalue - Verify that E is a modifiable lvalue. If not, 3461/// emit an error and return true. If so, return false. 3462static bool CheckForModifiableLvalue(Expr *E, SourceLocation Loc, Sema &S) { 3463 Expr::isModifiableLvalueResult IsLV = E->isModifiableLvalue(S.Context); 3464 if (IsLV == Expr::MLV_Valid && IsReadonlyProperty(E, S)) 3465 IsLV = Expr::MLV_ReadonlyProperty; 3466 if (IsLV == Expr::MLV_Valid) 3467 return false; 3468 3469 unsigned Diag = 0; 3470 bool NeedType = false; 3471 switch (IsLV) { // C99 6.5.16p2 3472 default: assert(0 && "Unknown result from isModifiableLvalue!"); 3473 case Expr::MLV_ConstQualified: Diag = diag::err_typecheck_assign_const; break; 3474 case Expr::MLV_ArrayType: 3475 Diag = diag::err_typecheck_array_not_modifiable_lvalue; 3476 NeedType = true; 3477 break; 3478 case Expr::MLV_NotObjectType: 3479 Diag = diag::err_typecheck_non_object_not_modifiable_lvalue; 3480 NeedType = true; 3481 break; 3482 case Expr::MLV_LValueCast: 3483 Diag = diag::err_typecheck_lvalue_casts_not_supported; 3484 break; 3485 case Expr::MLV_InvalidExpression: 3486 Diag = diag::err_typecheck_expression_not_modifiable_lvalue; 3487 break; 3488 case Expr::MLV_IncompleteType: 3489 case Expr::MLV_IncompleteVoidType: 3490 return S.RequireCompleteType(Loc, E->getType(), 3491 diag::err_typecheck_incomplete_type_not_modifiable_lvalue, 3492 E->getSourceRange()); 3493 case Expr::MLV_DuplicateVectorComponents: 3494 Diag = diag::err_typecheck_duplicate_vector_components_not_mlvalue; 3495 break; 3496 case Expr::MLV_NotBlockQualified: 3497 Diag = diag::err_block_decl_ref_not_modifiable_lvalue; 3498 break; 3499 case Expr::MLV_ReadonlyProperty: 3500 Diag = diag::error_readonly_property_assignment; 3501 break; 3502 case Expr::MLV_NoSetterProperty: 3503 Diag = diag::error_nosetter_property_assignment; 3504 break; 3505 } 3506 3507 if (NeedType) 3508 S.Diag(Loc, Diag) << E->getType() << E->getSourceRange(); 3509 else 3510 S.Diag(Loc, Diag) << E->getSourceRange(); 3511 return true; 3512} 3513 3514 3515 3516// C99 6.5.16.1 3517QualType Sema::CheckAssignmentOperands(Expr *LHS, Expr *&RHS, 3518 SourceLocation Loc, 3519 QualType CompoundType) { 3520 // Verify that LHS is a modifiable lvalue, and emit error if not. 3521 if (CheckForModifiableLvalue(LHS, Loc, *this)) 3522 return QualType(); 3523 3524 QualType LHSType = LHS->getType(); 3525 QualType RHSType = CompoundType.isNull() ? RHS->getType() : CompoundType; 3526 3527 AssignConvertType ConvTy; 3528 if (CompoundType.isNull()) { 3529 // Simple assignment "x = y". 3530 ConvTy = CheckSingleAssignmentConstraints(LHSType, RHS); 3531 // Special case of NSObject attributes on c-style pointer types. 3532 if (ConvTy == IncompatiblePointer && 3533 ((Context.isObjCNSObjectType(LHSType) && 3534 Context.isObjCObjectPointerType(RHSType)) || 3535 (Context.isObjCNSObjectType(RHSType) && 3536 Context.isObjCObjectPointerType(LHSType)))) 3537 ConvTy = Compatible; 3538 3539 // If the RHS is a unary plus or minus, check to see if they = and + are 3540 // right next to each other. If so, the user may have typo'd "x =+ 4" 3541 // instead of "x += 4". 3542 Expr *RHSCheck = RHS; 3543 if (ImplicitCastExpr *ICE = dyn_cast<ImplicitCastExpr>(RHSCheck)) 3544 RHSCheck = ICE->getSubExpr(); 3545 if (UnaryOperator *UO = dyn_cast<UnaryOperator>(RHSCheck)) { 3546 if ((UO->getOpcode() == UnaryOperator::Plus || 3547 UO->getOpcode() == UnaryOperator::Minus) && 3548 Loc.isFileID() && UO->getOperatorLoc().isFileID() && 3549 // Only if the two operators are exactly adjacent. 3550 Loc.getFileLocWithOffset(1) == UO->getOperatorLoc() && 3551 // And there is a space or other character before the subexpr of the 3552 // unary +/-. We don't want to warn on "x=-1". 3553 Loc.getFileLocWithOffset(2) != UO->getSubExpr()->getLocStart() && 3554 UO->getSubExpr()->getLocStart().isFileID()) { 3555 Diag(Loc, diag::warn_not_compound_assign) 3556 << (UO->getOpcode() == UnaryOperator::Plus ? "+" : "-") 3557 << SourceRange(UO->getOperatorLoc(), UO->getOperatorLoc()); 3558 } 3559 } 3560 } else { 3561 // Compound assignment "x += y" 3562 ConvTy = CheckCompoundAssignmentConstraints(LHSType, RHSType); 3563 } 3564 3565 if (DiagnoseAssignmentResult(ConvTy, Loc, LHSType, RHSType, 3566 RHS, "assigning")) 3567 return QualType(); 3568 3569 // C99 6.5.16p3: The type of an assignment expression is the type of the 3570 // left operand unless the left operand has qualified type, in which case 3571 // it is the unqualified version of the type of the left operand. 3572 // C99 6.5.16.1p2: In simple assignment, the value of the right operand 3573 // is converted to the type of the assignment expression (above). 3574 // C++ 5.17p1: the type of the assignment expression is that of its left 3575 // oprdu. 3576 return LHSType.getUnqualifiedType(); 3577} 3578 3579// C99 6.5.17 3580QualType Sema::CheckCommaOperands(Expr *LHS, Expr *&RHS, SourceLocation Loc) { 3581 // FIXME: what is required for LHS? 3582 3583 // Comma performs lvalue conversion (C99 6.3.2.1), but not unary conversions. 3584 DefaultFunctionArrayConversion(RHS); 3585 return RHS->getType(); 3586} 3587 3588/// CheckIncrementDecrementOperand - unlike most "Check" methods, this routine 3589/// doesn't need to call UsualUnaryConversions or UsualArithmeticConversions. 3590QualType Sema::CheckIncrementDecrementOperand(Expr *Op, SourceLocation OpLoc, 3591 bool isInc) { 3592 if (Op->isTypeDependent()) 3593 return Context.DependentTy; 3594 3595 QualType ResType = Op->getType(); 3596 assert(!ResType.isNull() && "no type for increment/decrement expression"); 3597 3598 if (getLangOptions().CPlusPlus && ResType->isBooleanType()) { 3599 // Decrement of bool is not allowed. 3600 if (!isInc) { 3601 Diag(OpLoc, diag::err_decrement_bool) << Op->getSourceRange(); 3602 return QualType(); 3603 } 3604 // Increment of bool sets it to true, but is deprecated. 3605 Diag(OpLoc, diag::warn_increment_bool) << Op->getSourceRange(); 3606 } else if (ResType->isRealType()) { 3607 // OK! 3608 } else if (const PointerType *PT = ResType->getAsPointerType()) { 3609 // C99 6.5.2.4p2, 6.5.6p2 3610 if (PT->getPointeeType()->isObjectType()) { 3611 // Pointer to object is ok! 3612 } else if (PT->getPointeeType()->isVoidType()) { 3613 if (getLangOptions().CPlusPlus) { 3614 Diag(OpLoc, diag::err_typecheck_pointer_arith_void_type) 3615 << Op->getSourceRange(); 3616 return QualType(); 3617 } 3618 3619 // Pointer to void is a GNU extension in C. 3620 Diag(OpLoc, diag::ext_gnu_void_ptr) << Op->getSourceRange(); 3621 } else if (PT->getPointeeType()->isFunctionType()) { 3622 if (getLangOptions().CPlusPlus) { 3623 Diag(OpLoc, diag::err_typecheck_pointer_arith_function_type) 3624 << Op->getType() << Op->getSourceRange(); 3625 return QualType(); 3626 } 3627 3628 Diag(OpLoc, diag::ext_gnu_ptr_func_arith) 3629 << ResType << Op->getSourceRange(); 3630 } else { 3631 RequireCompleteType(OpLoc, PT->getPointeeType(), 3632 diag::err_typecheck_arithmetic_incomplete_type, 3633 Op->getSourceRange(), SourceRange(), 3634 ResType); 3635 return QualType(); 3636 } 3637 } else if (ResType->isComplexType()) { 3638 // C99 does not support ++/-- on complex types, we allow as an extension. 3639 Diag(OpLoc, diag::ext_integer_increment_complex) 3640 << ResType << Op->getSourceRange(); 3641 } else { 3642 Diag(OpLoc, diag::err_typecheck_illegal_increment_decrement) 3643 << ResType << Op->getSourceRange(); 3644 return QualType(); 3645 } 3646 // At this point, we know we have a real, complex or pointer type. 3647 // Now make sure the operand is a modifiable lvalue. 3648 if (CheckForModifiableLvalue(Op, OpLoc, *this)) 3649 return QualType(); 3650 return ResType; 3651} 3652 3653/// getPrimaryDecl - Helper function for CheckAddressOfOperand(). 3654/// This routine allows us to typecheck complex/recursive expressions 3655/// where the declaration is needed for type checking. We only need to 3656/// handle cases when the expression references a function designator 3657/// or is an lvalue. Here are some examples: 3658/// - &(x) => x 3659/// - &*****f => f for f a function designator. 3660/// - &s.xx => s 3661/// - &s.zz[1].yy -> s, if zz is an array 3662/// - *(x + 1) -> x, if x is an array 3663/// - &"123"[2] -> 0 3664/// - & __real__ x -> x 3665static NamedDecl *getPrimaryDecl(Expr *E) { 3666 switch (E->getStmtClass()) { 3667 case Stmt::DeclRefExprClass: 3668 case Stmt::QualifiedDeclRefExprClass: 3669 return cast<DeclRefExpr>(E)->getDecl(); 3670 case Stmt::MemberExprClass: 3671 // Fields cannot be declared with a 'register' storage class. 3672 // &X->f is always ok, even if X is declared register. 3673 if (cast<MemberExpr>(E)->isArrow()) 3674 return 0; 3675 return getPrimaryDecl(cast<MemberExpr>(E)->getBase()); 3676 case Stmt::ArraySubscriptExprClass: { 3677 // &X[4] and &4[X] refers to X if X is not a pointer. 3678 3679 NamedDecl *D = getPrimaryDecl(cast<ArraySubscriptExpr>(E)->getBase()); 3680 ValueDecl *VD = dyn_cast_or_null<ValueDecl>(D); 3681 if (!VD || VD->getType()->isPointerType()) 3682 return 0; 3683 else 3684 return VD; 3685 } 3686 case Stmt::UnaryOperatorClass: { 3687 UnaryOperator *UO = cast<UnaryOperator>(E); 3688 3689 switch(UO->getOpcode()) { 3690 case UnaryOperator::Deref: { 3691 // *(X + 1) refers to X if X is not a pointer. 3692 if (NamedDecl *D = getPrimaryDecl(UO->getSubExpr())) { 3693 ValueDecl *VD = dyn_cast<ValueDecl>(D); 3694 if (!VD || VD->getType()->isPointerType()) 3695 return 0; 3696 return VD; 3697 } 3698 return 0; 3699 } 3700 case UnaryOperator::Real: 3701 case UnaryOperator::Imag: 3702 case UnaryOperator::Extension: 3703 return getPrimaryDecl(UO->getSubExpr()); 3704 default: 3705 return 0; 3706 } 3707 } 3708 case Stmt::BinaryOperatorClass: { 3709 BinaryOperator *BO = cast<BinaryOperator>(E); 3710 3711 // Handle cases involving pointer arithmetic. The result of an 3712 // Assign or AddAssign is not an lvalue so they can be ignored. 3713 3714 // (x + n) or (n + x) => x 3715 if (BO->getOpcode() == BinaryOperator::Add) { 3716 if (BO->getLHS()->getType()->isPointerType()) { 3717 return getPrimaryDecl(BO->getLHS()); 3718 } else if (BO->getRHS()->getType()->isPointerType()) { 3719 return getPrimaryDecl(BO->getRHS()); 3720 } 3721 } 3722 3723 return 0; 3724 } 3725 case Stmt::ParenExprClass: 3726 return getPrimaryDecl(cast<ParenExpr>(E)->getSubExpr()); 3727 case Stmt::ImplicitCastExprClass: 3728 // &X[4] when X is an array, has an implicit cast from array to pointer. 3729 return getPrimaryDecl(cast<ImplicitCastExpr>(E)->getSubExpr()); 3730 default: 3731 return 0; 3732 } 3733} 3734 3735/// CheckAddressOfOperand - The operand of & must be either a function 3736/// designator or an lvalue designating an object. If it is an lvalue, the 3737/// object cannot be declared with storage class register or be a bit field. 3738/// Note: The usual conversions are *not* applied to the operand of the & 3739/// operator (C99 6.3.2.1p[2-4]), and its result is never an lvalue. 3740/// In C++, the operand might be an overloaded function name, in which case 3741/// we allow the '&' but retain the overloaded-function type. 3742QualType Sema::CheckAddressOfOperand(Expr *op, SourceLocation OpLoc) { 3743 if (op->isTypeDependent()) 3744 return Context.DependentTy; 3745 3746 if (getLangOptions().C99) { 3747 // Implement C99-only parts of addressof rules. 3748 if (UnaryOperator* uOp = dyn_cast<UnaryOperator>(op)) { 3749 if (uOp->getOpcode() == UnaryOperator::Deref) 3750 // Per C99 6.5.3.2, the address of a deref always returns a valid result 3751 // (assuming the deref expression is valid). 3752 return uOp->getSubExpr()->getType(); 3753 } 3754 // Technically, there should be a check for array subscript 3755 // expressions here, but the result of one is always an lvalue anyway. 3756 } 3757 NamedDecl *dcl = getPrimaryDecl(op); 3758 Expr::isLvalueResult lval = op->isLvalue(Context); 3759 3760 if (lval != Expr::LV_Valid) { // C99 6.5.3.2p1 3761 if (!dcl || !isa<FunctionDecl>(dcl)) {// allow function designators 3762 // FIXME: emit more specific diag... 3763 Diag(OpLoc, diag::err_typecheck_invalid_lvalue_addrof) 3764 << op->getSourceRange(); 3765 return QualType(); 3766 } 3767 } else if (MemberExpr *MemExpr = dyn_cast<MemberExpr>(op)) { // C99 6.5.3.2p1 3768 if (FieldDecl *Field = dyn_cast<FieldDecl>(MemExpr->getMemberDecl())) { 3769 if (Field->isBitField()) { 3770 Diag(OpLoc, diag::err_typecheck_address_of) 3771 << "bit-field" << op->getSourceRange(); 3772 return QualType(); 3773 } 3774 } 3775 // Check for Apple extension for accessing vector components. 3776 } else if (isa<ExtVectorElementExpr>(op) || (isa<ArraySubscriptExpr>(op) && 3777 cast<ArraySubscriptExpr>(op)->getBase()->getType()->isVectorType())){ 3778 Diag(OpLoc, diag::err_typecheck_address_of) 3779 << "vector element" << op->getSourceRange(); 3780 return QualType(); 3781 } else if (dcl) { // C99 6.5.3.2p1 3782 // We have an lvalue with a decl. Make sure the decl is not declared 3783 // with the register storage-class specifier. 3784 if (const VarDecl *vd = dyn_cast<VarDecl>(dcl)) { 3785 if (vd->getStorageClass() == VarDecl::Register) { 3786 Diag(OpLoc, diag::err_typecheck_address_of) 3787 << "register variable" << op->getSourceRange(); 3788 return QualType(); 3789 } 3790 } else if (isa<OverloadedFunctionDecl>(dcl)) { 3791 return Context.OverloadTy; 3792 } else if (isa<FieldDecl>(dcl)) { 3793 // Okay: we can take the address of a field. 3794 // Could be a pointer to member, though, if there is an explicit 3795 // scope qualifier for the class. 3796 if (isa<QualifiedDeclRefExpr>(op)) { 3797 DeclContext *Ctx = dcl->getDeclContext(); 3798 if (Ctx && Ctx->isRecord()) 3799 return Context.getMemberPointerType(op->getType(), 3800 Context.getTypeDeclType(cast<RecordDecl>(Ctx)).getTypePtr()); 3801 } 3802 } else if (isa<FunctionDecl>(dcl)) { 3803 // Okay: we can take the address of a function. 3804 // As above. 3805 if (isa<QualifiedDeclRefExpr>(op)) { 3806 DeclContext *Ctx = dcl->getDeclContext(); 3807 if (Ctx && Ctx->isRecord()) 3808 return Context.getMemberPointerType(op->getType(), 3809 Context.getTypeDeclType(cast<RecordDecl>(Ctx)).getTypePtr()); 3810 } 3811 } 3812 else 3813 assert(0 && "Unknown/unexpected decl type"); 3814 } 3815 3816 // If the operand has type "type", the result has type "pointer to type". 3817 return Context.getPointerType(op->getType()); 3818} 3819 3820QualType Sema::CheckIndirectionOperand(Expr *Op, SourceLocation OpLoc) { 3821 if (Op->isTypeDependent()) 3822 return Context.DependentTy; 3823 3824 UsualUnaryConversions(Op); 3825 QualType Ty = Op->getType(); 3826 3827 // Note that per both C89 and C99, this is always legal, even if ptype is an 3828 // incomplete type or void. It would be possible to warn about dereferencing 3829 // a void pointer, but it's completely well-defined, and such a warning is 3830 // unlikely to catch any mistakes. 3831 if (const PointerType *PT = Ty->getAsPointerType()) 3832 return PT->getPointeeType(); 3833 3834 Diag(OpLoc, diag::err_typecheck_indirection_requires_pointer) 3835 << Ty << Op->getSourceRange(); 3836 return QualType(); 3837} 3838 3839static inline BinaryOperator::Opcode ConvertTokenKindToBinaryOpcode( 3840 tok::TokenKind Kind) { 3841 BinaryOperator::Opcode Opc; 3842 switch (Kind) { 3843 default: assert(0 && "Unknown binop!"); 3844 case tok::periodstar: Opc = BinaryOperator::PtrMemD; break; 3845 case tok::arrowstar: Opc = BinaryOperator::PtrMemI; break; 3846 case tok::star: Opc = BinaryOperator::Mul; break; 3847 case tok::slash: Opc = BinaryOperator::Div; break; 3848 case tok::percent: Opc = BinaryOperator::Rem; break; 3849 case tok::plus: Opc = BinaryOperator::Add; break; 3850 case tok::minus: Opc = BinaryOperator::Sub; break; 3851 case tok::lessless: Opc = BinaryOperator::Shl; break; 3852 case tok::greatergreater: Opc = BinaryOperator::Shr; break; 3853 case tok::lessequal: Opc = BinaryOperator::LE; break; 3854 case tok::less: Opc = BinaryOperator::LT; break; 3855 case tok::greaterequal: Opc = BinaryOperator::GE; break; 3856 case tok::greater: Opc = BinaryOperator::GT; break; 3857 case tok::exclaimequal: Opc = BinaryOperator::NE; break; 3858 case tok::equalequal: Opc = BinaryOperator::EQ; break; 3859 case tok::amp: Opc = BinaryOperator::And; break; 3860 case tok::caret: Opc = BinaryOperator::Xor; break; 3861 case tok::pipe: Opc = BinaryOperator::Or; break; 3862 case tok::ampamp: Opc = BinaryOperator::LAnd; break; 3863 case tok::pipepipe: Opc = BinaryOperator::LOr; break; 3864 case tok::equal: Opc = BinaryOperator::Assign; break; 3865 case tok::starequal: Opc = BinaryOperator::MulAssign; break; 3866 case tok::slashequal: Opc = BinaryOperator::DivAssign; break; 3867 case tok::percentequal: Opc = BinaryOperator::RemAssign; break; 3868 case tok::plusequal: Opc = BinaryOperator::AddAssign; break; 3869 case tok::minusequal: Opc = BinaryOperator::SubAssign; break; 3870 case tok::lesslessequal: Opc = BinaryOperator::ShlAssign; break; 3871 case tok::greatergreaterequal: Opc = BinaryOperator::ShrAssign; break; 3872 case tok::ampequal: Opc = BinaryOperator::AndAssign; break; 3873 case tok::caretequal: Opc = BinaryOperator::XorAssign; break; 3874 case tok::pipeequal: Opc = BinaryOperator::OrAssign; break; 3875 case tok::comma: Opc = BinaryOperator::Comma; break; 3876 } 3877 return Opc; 3878} 3879 3880static inline UnaryOperator::Opcode ConvertTokenKindToUnaryOpcode( 3881 tok::TokenKind Kind) { 3882 UnaryOperator::Opcode Opc; 3883 switch (Kind) { 3884 default: assert(0 && "Unknown unary op!"); 3885 case tok::plusplus: Opc = UnaryOperator::PreInc; break; 3886 case tok::minusminus: Opc = UnaryOperator::PreDec; break; 3887 case tok::amp: Opc = UnaryOperator::AddrOf; break; 3888 case tok::star: Opc = UnaryOperator::Deref; break; 3889 case tok::plus: Opc = UnaryOperator::Plus; break; 3890 case tok::minus: Opc = UnaryOperator::Minus; break; 3891 case tok::tilde: Opc = UnaryOperator::Not; break; 3892 case tok::exclaim: Opc = UnaryOperator::LNot; break; 3893 case tok::kw___real: Opc = UnaryOperator::Real; break; 3894 case tok::kw___imag: Opc = UnaryOperator::Imag; break; 3895 case tok::kw___extension__: Opc = UnaryOperator::Extension; break; 3896 } 3897 return Opc; 3898} 3899 3900/// CreateBuiltinBinOp - Creates a new built-in binary operation with 3901/// operator @p Opc at location @c TokLoc. This routine only supports 3902/// built-in operations; ActOnBinOp handles overloaded operators. 3903Action::OwningExprResult Sema::CreateBuiltinBinOp(SourceLocation OpLoc, 3904 unsigned Op, 3905 Expr *lhs, Expr *rhs) { 3906 QualType ResultTy; // Result type of the binary operator. 3907 QualType CompTy; // Computation type for compound assignments (e.g. '+=') 3908 BinaryOperator::Opcode Opc = (BinaryOperator::Opcode)Op; 3909 3910 switch (Opc) { 3911 case BinaryOperator::Assign: 3912 ResultTy = CheckAssignmentOperands(lhs, rhs, OpLoc, QualType()); 3913 break; 3914 case BinaryOperator::PtrMemD: 3915 case BinaryOperator::PtrMemI: 3916 ResultTy = CheckPointerToMemberOperands(lhs, rhs, OpLoc, 3917 Opc == BinaryOperator::PtrMemI); 3918 break; 3919 case BinaryOperator::Mul: 3920 case BinaryOperator::Div: 3921 ResultTy = CheckMultiplyDivideOperands(lhs, rhs, OpLoc); 3922 break; 3923 case BinaryOperator::Rem: 3924 ResultTy = CheckRemainderOperands(lhs, rhs, OpLoc); 3925 break; 3926 case BinaryOperator::Add: 3927 ResultTy = CheckAdditionOperands(lhs, rhs, OpLoc); 3928 break; 3929 case BinaryOperator::Sub: 3930 ResultTy = CheckSubtractionOperands(lhs, rhs, OpLoc); 3931 break; 3932 case BinaryOperator::Shl: 3933 case BinaryOperator::Shr: 3934 ResultTy = CheckShiftOperands(lhs, rhs, OpLoc); 3935 break; 3936 case BinaryOperator::LE: 3937 case BinaryOperator::LT: 3938 case BinaryOperator::GE: 3939 case BinaryOperator::GT: 3940 ResultTy = CheckCompareOperands(lhs, rhs, OpLoc, true); 3941 break; 3942 case BinaryOperator::EQ: 3943 case BinaryOperator::NE: 3944 ResultTy = CheckCompareOperands(lhs, rhs, OpLoc, false); 3945 break; 3946 case BinaryOperator::And: 3947 case BinaryOperator::Xor: 3948 case BinaryOperator::Or: 3949 ResultTy = CheckBitwiseOperands(lhs, rhs, OpLoc); 3950 break; 3951 case BinaryOperator::LAnd: 3952 case BinaryOperator::LOr: 3953 ResultTy = CheckLogicalOperands(lhs, rhs, OpLoc); 3954 break; 3955 case BinaryOperator::MulAssign: 3956 case BinaryOperator::DivAssign: 3957 CompTy = CheckMultiplyDivideOperands(lhs, rhs, OpLoc, true); 3958 if (!CompTy.isNull()) 3959 ResultTy = CheckAssignmentOperands(lhs, rhs, OpLoc, CompTy); 3960 break; 3961 case BinaryOperator::RemAssign: 3962 CompTy = CheckRemainderOperands(lhs, rhs, OpLoc, true); 3963 if (!CompTy.isNull()) 3964 ResultTy = CheckAssignmentOperands(lhs, rhs, OpLoc, CompTy); 3965 break; 3966 case BinaryOperator::AddAssign: 3967 CompTy = CheckAdditionOperands(lhs, rhs, OpLoc, true); 3968 if (!CompTy.isNull()) 3969 ResultTy = CheckAssignmentOperands(lhs, rhs, OpLoc, CompTy); 3970 break; 3971 case BinaryOperator::SubAssign: 3972 CompTy = CheckSubtractionOperands(lhs, rhs, OpLoc, true); 3973 if (!CompTy.isNull()) 3974 ResultTy = CheckAssignmentOperands(lhs, rhs, OpLoc, CompTy); 3975 break; 3976 case BinaryOperator::ShlAssign: 3977 case BinaryOperator::ShrAssign: 3978 CompTy = CheckShiftOperands(lhs, rhs, OpLoc, true); 3979 if (!CompTy.isNull()) 3980 ResultTy = CheckAssignmentOperands(lhs, rhs, OpLoc, CompTy); 3981 break; 3982 case BinaryOperator::AndAssign: 3983 case BinaryOperator::XorAssign: 3984 case BinaryOperator::OrAssign: 3985 CompTy = CheckBitwiseOperands(lhs, rhs, OpLoc, true); 3986 if (!CompTy.isNull()) 3987 ResultTy = CheckAssignmentOperands(lhs, rhs, OpLoc, CompTy); 3988 break; 3989 case BinaryOperator::Comma: 3990 ResultTy = CheckCommaOperands(lhs, rhs, OpLoc); 3991 break; 3992 } 3993 if (ResultTy.isNull()) 3994 return ExprError(); 3995 if (CompTy.isNull()) 3996 return Owned(new (Context) BinaryOperator(lhs, rhs, Opc, ResultTy, OpLoc)); 3997 else 3998 return Owned(new (Context) CompoundAssignOperator(lhs, rhs, Opc, ResultTy, 3999 CompTy, OpLoc)); 4000} 4001 4002// Binary Operators. 'Tok' is the token for the operator. 4003Action::OwningExprResult Sema::ActOnBinOp(Scope *S, SourceLocation TokLoc, 4004 tok::TokenKind Kind, 4005 ExprArg LHS, ExprArg RHS) { 4006 BinaryOperator::Opcode Opc = ConvertTokenKindToBinaryOpcode(Kind); 4007 Expr *lhs = (Expr *)LHS.release(), *rhs = (Expr*)RHS.release(); 4008 4009 assert((lhs != 0) && "ActOnBinOp(): missing left expression"); 4010 assert((rhs != 0) && "ActOnBinOp(): missing right expression"); 4011 4012 if (getLangOptions().CPlusPlus && 4013 (lhs->getType()->isOverloadableType() || 4014 rhs->getType()->isOverloadableType())) { 4015 // Find all of the overloaded operators visible from this 4016 // point. We perform both an operator-name lookup from the local 4017 // scope and an argument-dependent lookup based on the types of 4018 // the arguments. 4019 FunctionSet Functions; 4020 OverloadedOperatorKind OverOp = BinaryOperator::getOverloadedOperator(Opc); 4021 if (OverOp != OO_None) { 4022 LookupOverloadedOperatorName(OverOp, S, lhs->getType(), rhs->getType(), 4023 Functions); 4024 Expr *Args[2] = { lhs, rhs }; 4025 DeclarationName OpName 4026 = Context.DeclarationNames.getCXXOperatorName(OverOp); 4027 ArgumentDependentLookup(OpName, Args, 2, Functions); 4028 } 4029 4030 // Build the (potentially-overloaded, potentially-dependent) 4031 // binary operation. 4032 return CreateOverloadedBinOp(TokLoc, Opc, Functions, lhs, rhs); 4033 } 4034 4035 // Build a built-in binary operation. 4036 return CreateBuiltinBinOp(TokLoc, Opc, lhs, rhs); 4037} 4038 4039Action::OwningExprResult Sema::CreateBuiltinUnaryOp(SourceLocation OpLoc, 4040 unsigned OpcIn, 4041 ExprArg InputArg) { 4042 UnaryOperator::Opcode Opc = static_cast<UnaryOperator::Opcode>(OpcIn); 4043 4044 // FIXME: Input is modified below, but InputArg is not updated 4045 // appropriately. 4046 Expr *Input = (Expr *)InputArg.get(); 4047 QualType resultType; 4048 switch (Opc) { 4049 case UnaryOperator::PostInc: 4050 case UnaryOperator::PostDec: 4051 case UnaryOperator::OffsetOf: 4052 assert(false && "Invalid unary operator"); 4053 break; 4054 4055 case UnaryOperator::PreInc: 4056 case UnaryOperator::PreDec: 4057 resultType = CheckIncrementDecrementOperand(Input, OpLoc, 4058 Opc == UnaryOperator::PreInc); 4059 break; 4060 case UnaryOperator::AddrOf: 4061 resultType = CheckAddressOfOperand(Input, OpLoc); 4062 break; 4063 case UnaryOperator::Deref: 4064 DefaultFunctionArrayConversion(Input); 4065 resultType = CheckIndirectionOperand(Input, OpLoc); 4066 break; 4067 case UnaryOperator::Plus: 4068 case UnaryOperator::Minus: 4069 UsualUnaryConversions(Input); 4070 resultType = Input->getType(); 4071 if (resultType->isDependentType()) 4072 break; 4073 if (resultType->isArithmeticType()) // C99 6.5.3.3p1 4074 break; 4075 else if (getLangOptions().CPlusPlus && // C++ [expr.unary.op]p6-7 4076 resultType->isEnumeralType()) 4077 break; 4078 else if (getLangOptions().CPlusPlus && // C++ [expr.unary.op]p6 4079 Opc == UnaryOperator::Plus && 4080 resultType->isPointerType()) 4081 break; 4082 4083 return ExprError(Diag(OpLoc, diag::err_typecheck_unary_expr) 4084 << resultType << Input->getSourceRange()); 4085 case UnaryOperator::Not: // bitwise complement 4086 UsualUnaryConversions(Input); 4087 resultType = Input->getType(); 4088 if (resultType->isDependentType()) 4089 break; 4090 // C99 6.5.3.3p1. We allow complex int and float as a GCC extension. 4091 if (resultType->isComplexType() || resultType->isComplexIntegerType()) 4092 // C99 does not support '~' for complex conjugation. 4093 Diag(OpLoc, diag::ext_integer_complement_complex) 4094 << resultType << Input->getSourceRange(); 4095 else if (!resultType->isIntegerType()) 4096 return ExprError(Diag(OpLoc, diag::err_typecheck_unary_expr) 4097 << resultType << Input->getSourceRange()); 4098 break; 4099 case UnaryOperator::LNot: // logical negation 4100 // Unlike +/-/~, integer promotions aren't done here (C99 6.5.3.3p5). 4101 DefaultFunctionArrayConversion(Input); 4102 resultType = Input->getType(); 4103 if (resultType->isDependentType()) 4104 break; 4105 if (!resultType->isScalarType()) // C99 6.5.3.3p1 4106 return ExprError(Diag(OpLoc, diag::err_typecheck_unary_expr) 4107 << resultType << Input->getSourceRange()); 4108 // LNot always has type int. C99 6.5.3.3p5. 4109 // In C++, it's bool. C++ 5.3.1p8 4110 resultType = getLangOptions().CPlusPlus ? Context.BoolTy : Context.IntTy; 4111 break; 4112 case UnaryOperator::Real: 4113 case UnaryOperator::Imag: 4114 resultType = CheckRealImagOperand(Input, OpLoc, Opc == UnaryOperator::Real); 4115 break; 4116 case UnaryOperator::Extension: 4117 resultType = Input->getType(); 4118 break; 4119 } 4120 if (resultType.isNull()) 4121 return ExprError(); 4122 4123 InputArg.release(); 4124 return Owned(new (Context) UnaryOperator(Input, Opc, resultType, OpLoc)); 4125} 4126 4127// Unary Operators. 'Tok' is the token for the operator. 4128Action::OwningExprResult Sema::ActOnUnaryOp(Scope *S, SourceLocation OpLoc, 4129 tok::TokenKind Op, ExprArg input) { 4130 Expr *Input = (Expr*)input.get(); 4131 UnaryOperator::Opcode Opc = ConvertTokenKindToUnaryOpcode(Op); 4132 4133 if (getLangOptions().CPlusPlus && Input->getType()->isOverloadableType()) { 4134 // Find all of the overloaded operators visible from this 4135 // point. We perform both an operator-name lookup from the local 4136 // scope and an argument-dependent lookup based on the types of 4137 // the arguments. 4138 FunctionSet Functions; 4139 OverloadedOperatorKind OverOp = UnaryOperator::getOverloadedOperator(Opc); 4140 if (OverOp != OO_None) { 4141 LookupOverloadedOperatorName(OverOp, S, Input->getType(), QualType(), 4142 Functions); 4143 DeclarationName OpName 4144 = Context.DeclarationNames.getCXXOperatorName(OverOp); 4145 ArgumentDependentLookup(OpName, &Input, 1, Functions); 4146 } 4147 4148 return CreateOverloadedUnaryOp(OpLoc, Opc, Functions, move(input)); 4149 } 4150 4151 return CreateBuiltinUnaryOp(OpLoc, Opc, move(input)); 4152} 4153 4154/// ActOnAddrLabel - Parse the GNU address of label extension: "&&foo". 4155Sema::OwningExprResult Sema::ActOnAddrLabel(SourceLocation OpLoc, 4156 SourceLocation LabLoc, 4157 IdentifierInfo *LabelII) { 4158 // Look up the record for this label identifier. 4159 LabelStmt *&LabelDecl = CurBlock ? CurBlock->LabelMap[LabelII] : 4160 LabelMap[LabelII]; 4161 4162 // If we haven't seen this label yet, create a forward reference. It 4163 // will be validated and/or cleaned up in ActOnFinishFunctionBody. 4164 if (LabelDecl == 0) 4165 LabelDecl = new (Context) LabelStmt(LabLoc, LabelII, 0); 4166 4167 // Create the AST node. The address of a label always has type 'void*'. 4168 return Owned(new (Context) AddrLabelExpr(OpLoc, LabLoc, LabelDecl, 4169 Context.getPointerType(Context.VoidTy))); 4170} 4171 4172Sema::OwningExprResult 4173Sema::ActOnStmtExpr(SourceLocation LPLoc, StmtArg substmt, 4174 SourceLocation RPLoc) { // "({..})" 4175 Stmt *SubStmt = static_cast<Stmt*>(substmt.get()); 4176 assert(SubStmt && isa<CompoundStmt>(SubStmt) && "Invalid action invocation!"); 4177 CompoundStmt *Compound = cast<CompoundStmt>(SubStmt); 4178 4179 bool isFileScope = getCurFunctionOrMethodDecl() == 0; 4180 if (isFileScope) { 4181 return ExprError(Diag(LPLoc, diag::err_stmtexpr_file_scope)); 4182 } 4183 4184 // FIXME: there are a variety of strange constraints to enforce here, for 4185 // example, it is not possible to goto into a stmt expression apparently. 4186 // More semantic analysis is needed. 4187 4188 // FIXME: the last statement in the compount stmt has its value used. We 4189 // should not warn about it being unused. 4190 4191 // If there are sub stmts in the compound stmt, take the type of the last one 4192 // as the type of the stmtexpr. 4193 QualType Ty = Context.VoidTy; 4194 4195 if (!Compound->body_empty()) { 4196 Stmt *LastStmt = Compound->body_back(); 4197 // If LastStmt is a label, skip down through into the body. 4198 while (LabelStmt *Label = dyn_cast<LabelStmt>(LastStmt)) 4199 LastStmt = Label->getSubStmt(); 4200 4201 if (Expr *LastExpr = dyn_cast<Expr>(LastStmt)) 4202 Ty = LastExpr->getType(); 4203 } 4204 4205 substmt.release(); 4206 return Owned(new (Context) StmtExpr(Compound, Ty, LPLoc, RPLoc)); 4207} 4208 4209Sema::OwningExprResult Sema::ActOnBuiltinOffsetOf(Scope *S, 4210 SourceLocation BuiltinLoc, 4211 SourceLocation TypeLoc, 4212 TypeTy *argty, 4213 OffsetOfComponent *CompPtr, 4214 unsigned NumComponents, 4215 SourceLocation RPLoc) { 4216 // FIXME: This function leaks all expressions in the offset components on 4217 // error. 4218 QualType ArgTy = QualType::getFromOpaquePtr(argty); 4219 assert(!ArgTy.isNull() && "Missing type argument!"); 4220 4221 bool Dependent = ArgTy->isDependentType(); 4222 4223 // We must have at least one component that refers to the type, and the first 4224 // one is known to be a field designator. Verify that the ArgTy represents 4225 // a struct/union/class. 4226 if (!Dependent && !ArgTy->isRecordType()) 4227 return ExprError(Diag(TypeLoc, diag::err_offsetof_record_type) << ArgTy); 4228 4229 // FIXME: Does the type need to be complete? 4230 4231 // Otherwise, create a null pointer as the base, and iteratively process 4232 // the offsetof designators. 4233 QualType ArgTyPtr = Context.getPointerType(ArgTy); 4234 Expr* Res = new (Context) ImplicitValueInitExpr(ArgTyPtr); 4235 Res = new (Context) UnaryOperator(Res, UnaryOperator::Deref, 4236 ArgTy, SourceLocation()); 4237 4238 // offsetof with non-identifier designators (e.g. "offsetof(x, a.b[c])") are a 4239 // GCC extension, diagnose them. 4240 // FIXME: This diagnostic isn't actually visible because the location is in 4241 // a system header! 4242 if (NumComponents != 1) 4243 Diag(BuiltinLoc, diag::ext_offsetof_extended_field_designator) 4244 << SourceRange(CompPtr[1].LocStart, CompPtr[NumComponents-1].LocEnd); 4245 4246 if (!Dependent) { 4247 // FIXME: Dependent case loses a lot of information here. And probably 4248 // leaks like a sieve. 4249 for (unsigned i = 0; i != NumComponents; ++i) { 4250 const OffsetOfComponent &OC = CompPtr[i]; 4251 if (OC.isBrackets) { 4252 // Offset of an array sub-field. TODO: Should we allow vector elements? 4253 const ArrayType *AT = Context.getAsArrayType(Res->getType()); 4254 if (!AT) { 4255 Res->Destroy(Context); 4256 return ExprError(Diag(OC.LocEnd, diag::err_offsetof_array_type) 4257 << Res->getType()); 4258 } 4259 4260 // FIXME: C++: Verify that operator[] isn't overloaded. 4261 4262 // Promote the array so it looks more like a normal array subscript 4263 // expression. 4264 DefaultFunctionArrayConversion(Res); 4265 4266 // C99 6.5.2.1p1 4267 Expr *Idx = static_cast<Expr*>(OC.U.E); 4268 // FIXME: Leaks Res 4269 if (!Idx->isTypeDependent() && !Idx->getType()->isIntegerType()) 4270 return ExprError(Diag(Idx->getLocStart(), 4271 diag::err_typecheck_subscript) 4272 << Idx->getSourceRange()); 4273 4274 Res = new (Context) ArraySubscriptExpr(Res, Idx, AT->getElementType(), 4275 OC.LocEnd); 4276 continue; 4277 } 4278 4279 const RecordType *RC = Res->getType()->getAsRecordType(); 4280 if (!RC) { 4281 Res->Destroy(Context); 4282 return ExprError(Diag(OC.LocEnd, diag::err_offsetof_record_type) 4283 << Res->getType()); 4284 } 4285 4286 // Get the decl corresponding to this. 4287 RecordDecl *RD = RC->getDecl(); 4288 FieldDecl *MemberDecl 4289 = dyn_cast_or_null<FieldDecl>(LookupQualifiedName(RD, OC.U.IdentInfo, 4290 LookupMemberName) 4291 .getAsDecl()); 4292 // FIXME: Leaks Res 4293 if (!MemberDecl) 4294 return ExprError(Diag(BuiltinLoc, diag::err_typecheck_no_member) 4295 << OC.U.IdentInfo << SourceRange(OC.LocStart, OC.LocEnd)); 4296 4297 // FIXME: C++: Verify that MemberDecl isn't a static field. 4298 // FIXME: Verify that MemberDecl isn't a bitfield. 4299 // MemberDecl->getType() doesn't get the right qualifiers, but it doesn't 4300 // matter here. 4301 Res = new (Context) MemberExpr(Res, false, MemberDecl, OC.LocEnd, 4302 MemberDecl->getType().getNonReferenceType()); 4303 } 4304 } 4305 4306 return Owned(new (Context) UnaryOperator(Res, UnaryOperator::OffsetOf, 4307 Context.getSizeType(), BuiltinLoc)); 4308} 4309 4310 4311Sema::OwningExprResult Sema::ActOnTypesCompatibleExpr(SourceLocation BuiltinLoc, 4312 TypeTy *arg1,TypeTy *arg2, 4313 SourceLocation RPLoc) { 4314 QualType argT1 = QualType::getFromOpaquePtr(arg1); 4315 QualType argT2 = QualType::getFromOpaquePtr(arg2); 4316 4317 assert((!argT1.isNull() && !argT2.isNull()) && "Missing type argument(s)"); 4318 4319 return Owned(new (Context) TypesCompatibleExpr(Context.IntTy, BuiltinLoc, 4320 argT1, argT2, RPLoc)); 4321} 4322 4323Sema::OwningExprResult Sema::ActOnChooseExpr(SourceLocation BuiltinLoc, 4324 ExprArg cond, 4325 ExprArg expr1, ExprArg expr2, 4326 SourceLocation RPLoc) { 4327 Expr *CondExpr = static_cast<Expr*>(cond.get()); 4328 Expr *LHSExpr = static_cast<Expr*>(expr1.get()); 4329 Expr *RHSExpr = static_cast<Expr*>(expr2.get()); 4330 4331 assert((CondExpr && LHSExpr && RHSExpr) && "Missing type argument(s)"); 4332 4333 QualType resType; 4334 if (CondExpr->isValueDependent()) { 4335 resType = Context.DependentTy; 4336 } else { 4337 // The conditional expression is required to be a constant expression. 4338 llvm::APSInt condEval(32); 4339 SourceLocation ExpLoc; 4340 if (!CondExpr->isIntegerConstantExpr(condEval, Context, &ExpLoc)) 4341 return ExprError(Diag(ExpLoc, 4342 diag::err_typecheck_choose_expr_requires_constant) 4343 << CondExpr->getSourceRange()); 4344 4345 // If the condition is > zero, then the AST type is the same as the LSHExpr. 4346 resType = condEval.getZExtValue() ? LHSExpr->getType() : RHSExpr->getType(); 4347 } 4348 4349 cond.release(); expr1.release(); expr2.release(); 4350 return Owned(new (Context) ChooseExpr(BuiltinLoc, CondExpr, LHSExpr, RHSExpr, 4351 resType, RPLoc)); 4352} 4353 4354//===----------------------------------------------------------------------===// 4355// Clang Extensions. 4356//===----------------------------------------------------------------------===// 4357 4358/// ActOnBlockStart - This callback is invoked when a block literal is started. 4359void Sema::ActOnBlockStart(SourceLocation CaretLoc, Scope *BlockScope) { 4360 // Analyze block parameters. 4361 BlockSemaInfo *BSI = new BlockSemaInfo(); 4362 4363 // Add BSI to CurBlock. 4364 BSI->PrevBlockInfo = CurBlock; 4365 CurBlock = BSI; 4366 4367 BSI->ReturnType = 0; 4368 BSI->TheScope = BlockScope; 4369 BSI->hasBlockDeclRefExprs = false; 4370 4371 BSI->TheDecl = BlockDecl::Create(Context, CurContext, CaretLoc); 4372 PushDeclContext(BlockScope, BSI->TheDecl); 4373} 4374 4375void Sema::ActOnBlockArguments(Declarator &ParamInfo, Scope *CurScope) { 4376 assert(ParamInfo.getIdentifier() == 0 && "block-id should have no identifier!"); 4377 4378 if (ParamInfo.getNumTypeObjects() == 0 4379 || ParamInfo.getTypeObject(0).Kind != DeclaratorChunk::Function) { 4380 QualType T = GetTypeForDeclarator(ParamInfo, CurScope); 4381 4382 // The type is entirely optional as well, if none, use DependentTy. 4383 if (T.isNull()) 4384 T = Context.DependentTy; 4385 4386 // The parameter list is optional, if there was none, assume (). 4387 if (!T->isFunctionType()) 4388 T = Context.getFunctionType(T, NULL, 0, 0, 0); 4389 4390 CurBlock->hasPrototype = true; 4391 CurBlock->isVariadic = false; 4392 Type *RetTy = T.getTypePtr()->getAsFunctionType()->getResultType() 4393 .getTypePtr(); 4394 4395 if (!RetTy->isDependentType()) 4396 CurBlock->ReturnType = RetTy; 4397 return; 4398 } 4399 4400 // Analyze arguments to block. 4401 assert(ParamInfo.getTypeObject(0).Kind == DeclaratorChunk::Function && 4402 "Not a function declarator!"); 4403 DeclaratorChunk::FunctionTypeInfo &FTI = ParamInfo.getTypeObject(0).Fun; 4404 4405 CurBlock->hasPrototype = FTI.hasPrototype; 4406 CurBlock->isVariadic = true; 4407 4408 // Check for C99 6.7.5.3p10 - foo(void) is a non-varargs function that takes 4409 // no arguments, not a function that takes a single void argument. 4410 if (FTI.hasPrototype && 4411 FTI.NumArgs == 1 && !FTI.isVariadic && FTI.ArgInfo[0].Ident == 0 && 4412 (!((ParmVarDecl *)FTI.ArgInfo[0].Param)->getType().getCVRQualifiers() && 4413 ((ParmVarDecl *)FTI.ArgInfo[0].Param)->getType()->isVoidType())) { 4414 // empty arg list, don't push any params. 4415 CurBlock->isVariadic = false; 4416 } else if (FTI.hasPrototype) { 4417 for (unsigned i = 0, e = FTI.NumArgs; i != e; ++i) 4418 CurBlock->Params.push_back((ParmVarDecl *)FTI.ArgInfo[i].Param); 4419 CurBlock->isVariadic = FTI.isVariadic; 4420 QualType T = GetTypeForDeclarator (ParamInfo, CurScope); 4421 4422 Type* RetTy = T.getTypePtr()->getAsFunctionType()->getResultType() 4423 .getTypePtr(); 4424 4425 if (!RetTy->isDependentType()) 4426 CurBlock->ReturnType = RetTy; 4427 } 4428 CurBlock->TheDecl->setParams(Context, &CurBlock->Params[0], 4429 CurBlock->Params.size()); 4430 4431 for (BlockDecl::param_iterator AI = CurBlock->TheDecl->param_begin(), 4432 E = CurBlock->TheDecl->param_end(); AI != E; ++AI) 4433 // If this has an identifier, add it to the scope stack. 4434 if ((*AI)->getIdentifier()) 4435 PushOnScopeChains(*AI, CurBlock->TheScope); 4436} 4437 4438/// ActOnBlockError - If there is an error parsing a block, this callback 4439/// is invoked to pop the information about the block from the action impl. 4440void Sema::ActOnBlockError(SourceLocation CaretLoc, Scope *CurScope) { 4441 // Ensure that CurBlock is deleted. 4442 llvm::OwningPtr<BlockSemaInfo> CC(CurBlock); 4443 4444 // Pop off CurBlock, handle nested blocks. 4445 CurBlock = CurBlock->PrevBlockInfo; 4446 4447 // FIXME: Delete the ParmVarDecl objects as well??? 4448 4449} 4450 4451/// ActOnBlockStmtExpr - This is called when the body of a block statement 4452/// literal was successfully completed. ^(int x){...} 4453Sema::OwningExprResult Sema::ActOnBlockStmtExpr(SourceLocation CaretLoc, 4454 StmtArg body, Scope *CurScope) { 4455 // Ensure that CurBlock is deleted. 4456 llvm::OwningPtr<BlockSemaInfo> BSI(CurBlock); 4457 4458 PopDeclContext(); 4459 4460 // Pop off CurBlock, handle nested blocks. 4461 CurBlock = CurBlock->PrevBlockInfo; 4462 4463 QualType RetTy = Context.VoidTy; 4464 if (BSI->ReturnType) 4465 RetTy = QualType(BSI->ReturnType, 0); 4466 4467 llvm::SmallVector<QualType, 8> ArgTypes; 4468 for (unsigned i = 0, e = BSI->Params.size(); i != e; ++i) 4469 ArgTypes.push_back(BSI->Params[i]->getType()); 4470 4471 QualType BlockTy; 4472 if (!BSI->hasPrototype) 4473 BlockTy = Context.getFunctionNoProtoType(RetTy); 4474 else 4475 BlockTy = Context.getFunctionType(RetTy, &ArgTypes[0], ArgTypes.size(), 4476 BSI->isVariadic, 0); 4477 4478 BlockTy = Context.getBlockPointerType(BlockTy); 4479 4480 BSI->TheDecl->setBody(static_cast<CompoundStmt*>(body.release())); 4481 return Owned(new (Context) BlockExpr(BSI->TheDecl, BlockTy, 4482 BSI->hasBlockDeclRefExprs)); 4483} 4484 4485Sema::OwningExprResult Sema::ActOnVAArg(SourceLocation BuiltinLoc, 4486 ExprArg expr, TypeTy *type, 4487 SourceLocation RPLoc) { 4488 QualType T = QualType::getFromOpaquePtr(type); 4489 4490 InitBuiltinVaListType(); 4491 4492 // Get the va_list type 4493 QualType VaListType = Context.getBuiltinVaListType(); 4494 // Deal with implicit array decay; for example, on x86-64, 4495 // va_list is an array, but it's supposed to decay to 4496 // a pointer for va_arg. 4497 if (VaListType->isArrayType()) 4498 VaListType = Context.getArrayDecayedType(VaListType); 4499 // Make sure the input expression also decays appropriately. 4500 Expr *E = static_cast<Expr*>(expr.get()); 4501 UsualUnaryConversions(E); 4502 4503 if (CheckAssignmentConstraints(VaListType, E->getType()) != Compatible) 4504 return ExprError(Diag(E->getLocStart(), 4505 diag::err_first_argument_to_va_arg_not_of_type_va_list) 4506 << E->getType() << E->getSourceRange()); 4507 4508 // FIXME: Warn if a non-POD type is passed in. 4509 4510 expr.release(); 4511 return Owned(new (Context) VAArgExpr(BuiltinLoc, E, T.getNonReferenceType(), 4512 RPLoc)); 4513} 4514 4515Sema::OwningExprResult Sema::ActOnGNUNullExpr(SourceLocation TokenLoc) { 4516 // The type of __null will be int or long, depending on the size of 4517 // pointers on the target. 4518 QualType Ty; 4519 if (Context.Target.getPointerWidth(0) == Context.Target.getIntWidth()) 4520 Ty = Context.IntTy; 4521 else 4522 Ty = Context.LongTy; 4523 4524 return Owned(new (Context) GNUNullExpr(Ty, TokenLoc)); 4525} 4526 4527bool Sema::DiagnoseAssignmentResult(AssignConvertType ConvTy, 4528 SourceLocation Loc, 4529 QualType DstType, QualType SrcType, 4530 Expr *SrcExpr, const char *Flavor) { 4531 // Decode the result (notice that AST's are still created for extensions). 4532 bool isInvalid = false; 4533 unsigned DiagKind; 4534 switch (ConvTy) { 4535 default: assert(0 && "Unknown conversion type"); 4536 case Compatible: return false; 4537 case PointerToInt: 4538 DiagKind = diag::ext_typecheck_convert_pointer_int; 4539 break; 4540 case IntToPointer: 4541 DiagKind = diag::ext_typecheck_convert_int_pointer; 4542 break; 4543 case IncompatiblePointer: 4544 DiagKind = diag::ext_typecheck_convert_incompatible_pointer; 4545 break; 4546 case FunctionVoidPointer: 4547 DiagKind = diag::ext_typecheck_convert_pointer_void_func; 4548 break; 4549 case CompatiblePointerDiscardsQualifiers: 4550 // If the qualifiers lost were because we were applying the 4551 // (deprecated) C++ conversion from a string literal to a char* 4552 // (or wchar_t*), then there was no error (C++ 4.2p2). FIXME: 4553 // Ideally, this check would be performed in 4554 // CheckPointerTypesForAssignment. However, that would require a 4555 // bit of refactoring (so that the second argument is an 4556 // expression, rather than a type), which should be done as part 4557 // of a larger effort to fix CheckPointerTypesForAssignment for 4558 // C++ semantics. 4559 if (getLangOptions().CPlusPlus && 4560 IsStringLiteralToNonConstPointerConversion(SrcExpr, DstType)) 4561 return false; 4562 DiagKind = diag::ext_typecheck_convert_discards_qualifiers; 4563 break; 4564 case IntToBlockPointer: 4565 DiagKind = diag::err_int_to_block_pointer; 4566 break; 4567 case IncompatibleBlockPointer: 4568 DiagKind = diag::ext_typecheck_convert_incompatible_block_pointer; 4569 break; 4570 case IncompatibleObjCQualifiedId: 4571 // FIXME: Diagnose the problem in ObjCQualifiedIdTypesAreCompatible, since 4572 // it can give a more specific diagnostic. 4573 DiagKind = diag::warn_incompatible_qualified_id; 4574 break; 4575 case IncompatibleVectors: 4576 DiagKind = diag::warn_incompatible_vectors; 4577 break; 4578 case Incompatible: 4579 DiagKind = diag::err_typecheck_convert_incompatible; 4580 isInvalid = true; 4581 break; 4582 } 4583 4584 Diag(Loc, DiagKind) << DstType << SrcType << Flavor 4585 << SrcExpr->getSourceRange(); 4586 return isInvalid; 4587} 4588 4589bool Sema::VerifyIntegerConstantExpression(const Expr* E, llvm::APSInt *Result) 4590{ 4591 Expr::EvalResult EvalResult; 4592 4593 if (!E->Evaluate(EvalResult, Context) || !EvalResult.Val.isInt() || 4594 EvalResult.HasSideEffects) { 4595 Diag(E->getExprLoc(), diag::err_expr_not_ice) << E->getSourceRange(); 4596 4597 if (EvalResult.Diag) { 4598 // We only show the note if it's not the usual "invalid subexpression" 4599 // or if it's actually in a subexpression. 4600 if (EvalResult.Diag != diag::note_invalid_subexpr_in_ice || 4601 E->IgnoreParens() != EvalResult.DiagExpr->IgnoreParens()) 4602 Diag(EvalResult.DiagLoc, EvalResult.Diag); 4603 } 4604 4605 return true; 4606 } 4607 4608 if (EvalResult.Diag) { 4609 Diag(E->getExprLoc(), diag::ext_expr_not_ice) << 4610 E->getSourceRange(); 4611 4612 // Print the reason it's not a constant. 4613 if (Diags.getDiagnosticLevel(diag::ext_expr_not_ice) != Diagnostic::Ignored) 4614 Diag(EvalResult.DiagLoc, EvalResult.Diag); 4615 } 4616 4617 if (Result) 4618 *Result = EvalResult.Val.getInt(); 4619 return false; 4620} 4621