SemaType.cpp revision 8a447af1297f4751f102a7ec060c6b303be7ccb5
1//===--- SemaType.cpp - Semantic Analysis for Types -----------------------===// 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 type-related semantic analysis. 11// 12//===----------------------------------------------------------------------===// 13 14#include "Sema.h" 15#include "clang/AST/ASTContext.h" 16#include "clang/AST/DeclObjC.h" 17#include "clang/AST/DeclTemplate.h" 18#include "clang/AST/Expr.h" 19#include "clang/Parse/DeclSpec.h" 20using namespace clang; 21 22/// \brief Perform adjustment on the parameter type of a function. 23/// 24/// This routine adjusts the given parameter type @p T to the actual 25/// parameter type used by semantic analysis (C99 6.7.5.3p[7,8], 26/// C++ [dcl.fct]p3). The adjusted parameter type is returned. 27QualType Sema::adjustParameterType(QualType T) { 28 // C99 6.7.5.3p7: 29 if (T->isArrayType()) { 30 // C99 6.7.5.3p7: 31 // A declaration of a parameter as "array of type" shall be 32 // adjusted to "qualified pointer to type", where the type 33 // qualifiers (if any) are those specified within the [ and ] of 34 // the array type derivation. 35 return Context.getArrayDecayedType(T); 36 } else if (T->isFunctionType()) 37 // C99 6.7.5.3p8: 38 // A declaration of a parameter as "function returning type" 39 // shall be adjusted to "pointer to function returning type", as 40 // in 6.3.2.1. 41 return Context.getPointerType(T); 42 43 return T; 44} 45 46/// \brief Convert the specified declspec to the appropriate type 47/// object. 48/// \param DS the declaration specifiers 49/// \param DeclLoc The location of the declarator identifier or invalid if none. 50/// \returns The type described by the declaration specifiers, or NULL 51/// if there was an error. 52QualType Sema::ConvertDeclSpecToType(const DeclSpec &DS, 53 SourceLocation DeclLoc) { 54 // FIXME: Should move the logic from DeclSpec::Finish to here for validity 55 // checking. 56 QualType Result; 57 58 switch (DS.getTypeSpecType()) { 59 case DeclSpec::TST_void: 60 Result = Context.VoidTy; 61 break; 62 case DeclSpec::TST_char: 63 if (DS.getTypeSpecSign() == DeclSpec::TSS_unspecified) 64 Result = Context.CharTy; 65 else if (DS.getTypeSpecSign() == DeclSpec::TSS_signed) 66 Result = Context.SignedCharTy; 67 else { 68 assert(DS.getTypeSpecSign() == DeclSpec::TSS_unsigned && 69 "Unknown TSS value"); 70 Result = Context.UnsignedCharTy; 71 } 72 break; 73 case DeclSpec::TST_wchar: 74 if (DS.getTypeSpecSign() == DeclSpec::TSS_unspecified) 75 Result = Context.WCharTy; 76 else if (DS.getTypeSpecSign() == DeclSpec::TSS_signed) { 77 Diag(DS.getTypeSpecSignLoc(), diag::ext_invalid_sign_spec) 78 << DS.getSpecifierName(DS.getTypeSpecType()); 79 Result = Context.getSignedWCharType(); 80 } else { 81 assert(DS.getTypeSpecSign() == DeclSpec::TSS_unsigned && 82 "Unknown TSS value"); 83 Diag(DS.getTypeSpecSignLoc(), diag::ext_invalid_sign_spec) 84 << DS.getSpecifierName(DS.getTypeSpecType()); 85 Result = Context.getUnsignedWCharType(); 86 } 87 break; 88 case DeclSpec::TST_unspecified: 89 // "<proto1,proto2>" is an objc qualified ID with a missing id. 90 if (DeclSpec::ProtocolQualifierListTy PQ = DS.getProtocolQualifiers()) { 91 Result = Context.getObjCQualifiedIdType((ObjCProtocolDecl**)PQ, 92 DS.getNumProtocolQualifiers()); 93 break; 94 } 95 96 // Unspecified typespec defaults to int in C90. However, the C90 grammar 97 // [C90 6.5] only allows a decl-spec if there was *some* type-specifier, 98 // type-qualifier, or storage-class-specifier. If not, emit an extwarn. 99 // Note that the one exception to this is function definitions, which are 100 // allowed to be completely missing a declspec. This is handled in the 101 // parser already though by it pretending to have seen an 'int' in this 102 // case. 103 if (getLangOptions().ImplicitInt) { 104 // In C89 mode, we only warn if there is a completely missing declspec 105 // when one is not allowed. 106 if (DS.isEmpty()) { 107 if (DeclLoc.isInvalid()) 108 DeclLoc = DS.getSourceRange().getBegin(); 109 Diag(DeclLoc, diag::warn_missing_declspec) 110 << DS.getSourceRange() 111 << CodeModificationHint::CreateInsertion(DS.getSourceRange().getBegin(), 112 "int"); 113 } 114 } else if (!DS.hasTypeSpecifier()) { 115 // C99 and C++ require a type specifier. For example, C99 6.7.2p2 says: 116 // "At least one type specifier shall be given in the declaration 117 // specifiers in each declaration, and in the specifier-qualifier list in 118 // each struct declaration and type name." 119 // FIXME: Does Microsoft really have the implicit int extension in C++? 120 if (DeclLoc.isInvalid()) 121 DeclLoc = DS.getSourceRange().getBegin(); 122 123 if (getLangOptions().CPlusPlus && !getLangOptions().Microsoft) 124 Diag(DeclLoc, diag::err_missing_type_specifier) 125 << DS.getSourceRange(); 126 else 127 Diag(DeclLoc, diag::warn_missing_type_specifier) 128 << DS.getSourceRange(); 129 130 // FIXME: If we could guarantee that the result would be 131 // well-formed, it would be useful to have a code insertion hint 132 // here. However, after emitting this warning/error, we often 133 // emit other errors. 134 } 135 136 // FALL THROUGH. 137 case DeclSpec::TST_int: { 138 if (DS.getTypeSpecSign() != DeclSpec::TSS_unsigned) { 139 switch (DS.getTypeSpecWidth()) { 140 case DeclSpec::TSW_unspecified: Result = Context.IntTy; break; 141 case DeclSpec::TSW_short: Result = Context.ShortTy; break; 142 case DeclSpec::TSW_long: Result = Context.LongTy; break; 143 case DeclSpec::TSW_longlong: Result = Context.LongLongTy; break; 144 } 145 } else { 146 switch (DS.getTypeSpecWidth()) { 147 case DeclSpec::TSW_unspecified: Result = Context.UnsignedIntTy; break; 148 case DeclSpec::TSW_short: Result = Context.UnsignedShortTy; break; 149 case DeclSpec::TSW_long: Result = Context.UnsignedLongTy; break; 150 case DeclSpec::TSW_longlong: Result =Context.UnsignedLongLongTy; break; 151 } 152 } 153 break; 154 } 155 case DeclSpec::TST_float: Result = Context.FloatTy; break; 156 case DeclSpec::TST_double: 157 if (DS.getTypeSpecWidth() == DeclSpec::TSW_long) 158 Result = Context.LongDoubleTy; 159 else 160 Result = Context.DoubleTy; 161 break; 162 case DeclSpec::TST_bool: Result = Context.BoolTy; break; // _Bool or bool 163 case DeclSpec::TST_decimal32: // _Decimal32 164 case DeclSpec::TST_decimal64: // _Decimal64 165 case DeclSpec::TST_decimal128: // _Decimal128 166 assert(0 && "FIXME: GNU decimal extensions not supported yet!"); 167 case DeclSpec::TST_class: 168 case DeclSpec::TST_enum: 169 case DeclSpec::TST_union: 170 case DeclSpec::TST_struct: { 171 Decl *D = static_cast<Decl *>(DS.getTypeRep()); 172 assert(D && "Didn't get a decl for a class/enum/union/struct?"); 173 assert(DS.getTypeSpecWidth() == 0 && DS.getTypeSpecComplex() == 0 && 174 DS.getTypeSpecSign() == 0 && 175 "Can't handle qualifiers on typedef names yet!"); 176 // TypeQuals handled by caller. 177 Result = Context.getTypeDeclType(cast<TypeDecl>(D)); 178 break; 179 } 180 case DeclSpec::TST_typename: { 181 assert(DS.getTypeSpecWidth() == 0 && DS.getTypeSpecComplex() == 0 && 182 DS.getTypeSpecSign() == 0 && 183 "Can't handle qualifiers on typedef names yet!"); 184 Result = QualType::getFromOpaquePtr(DS.getTypeRep()); 185 186 if (DeclSpec::ProtocolQualifierListTy PQ = DS.getProtocolQualifiers()) { 187 // FIXME: Adding a TST_objcInterface clause doesn't seem ideal, so 188 // we have this "hack" for now... 189 if (const ObjCInterfaceType *Interface = Result->getAsObjCInterfaceType()) 190 Result = Context.getObjCQualifiedInterfaceType(Interface->getDecl(), 191 (ObjCProtocolDecl**)PQ, 192 DS.getNumProtocolQualifiers()); 193 else if (Result == Context.getObjCIdType()) 194 // id<protocol-list> 195 Result = Context.getObjCQualifiedIdType((ObjCProtocolDecl**)PQ, 196 DS.getNumProtocolQualifiers()); 197 else if (Result == Context.getObjCClassType()) { 198 if (DeclLoc.isInvalid()) 199 DeclLoc = DS.getSourceRange().getBegin(); 200 // Class<protocol-list> 201 Diag(DeclLoc, diag::err_qualified_class_unsupported) 202 << DS.getSourceRange(); 203 } else { 204 if (DeclLoc.isInvalid()) 205 DeclLoc = DS.getSourceRange().getBegin(); 206 Diag(DeclLoc, diag::err_invalid_protocol_qualifiers) 207 << DS.getSourceRange(); 208 } 209 } 210 // TypeQuals handled by caller. 211 break; 212 } 213 case DeclSpec::TST_typeofType: 214 Result = QualType::getFromOpaquePtr(DS.getTypeRep()); 215 assert(!Result.isNull() && "Didn't get a type for typeof?"); 216 // TypeQuals handled by caller. 217 Result = Context.getTypeOfType(Result); 218 break; 219 case DeclSpec::TST_typeofExpr: { 220 Expr *E = static_cast<Expr *>(DS.getTypeRep()); 221 assert(E && "Didn't get an expression for typeof?"); 222 // TypeQuals handled by caller. 223 Result = Context.getTypeOfExprType(E); 224 break; 225 } 226 case DeclSpec::TST_error: 227 return QualType(); 228 } 229 230 // Handle complex types. 231 if (DS.getTypeSpecComplex() == DeclSpec::TSC_complex) { 232 if (getLangOptions().Freestanding) 233 Diag(DS.getTypeSpecComplexLoc(), diag::ext_freestanding_complex); 234 Result = Context.getComplexType(Result); 235 } 236 237 assert(DS.getTypeSpecComplex() != DeclSpec::TSC_imaginary && 238 "FIXME: imaginary types not supported yet!"); 239 240 // See if there are any attributes on the declspec that apply to the type (as 241 // opposed to the decl). 242 if (const AttributeList *AL = DS.getAttributes()) 243 ProcessTypeAttributeList(Result, AL); 244 245 // Apply const/volatile/restrict qualifiers to T. 246 if (unsigned TypeQuals = DS.getTypeQualifiers()) { 247 248 // Enforce C99 6.7.3p2: "Types other than pointer types derived from object 249 // or incomplete types shall not be restrict-qualified." C++ also allows 250 // restrict-qualified references. 251 if (TypeQuals & QualType::Restrict) { 252 if (Result->isPointerType() || Result->isReferenceType()) { 253 QualType EltTy = Result->isPointerType() ? 254 Result->getAsPointerType()->getPointeeType() : 255 Result->getAsReferenceType()->getPointeeType(); 256 257 // If we have a pointer or reference, the pointee must have an object 258 // incomplete type. 259 if (!EltTy->isIncompleteOrObjectType()) { 260 Diag(DS.getRestrictSpecLoc(), 261 diag::err_typecheck_invalid_restrict_invalid_pointee) 262 << EltTy << DS.getSourceRange(); 263 TypeQuals &= ~QualType::Restrict; // Remove the restrict qualifier. 264 } 265 } else { 266 Diag(DS.getRestrictSpecLoc(), 267 diag::err_typecheck_invalid_restrict_not_pointer) 268 << Result << DS.getSourceRange(); 269 TypeQuals &= ~QualType::Restrict; // Remove the restrict qualifier. 270 } 271 } 272 273 // Warn about CV qualifiers on functions: C99 6.7.3p8: "If the specification 274 // of a function type includes any type qualifiers, the behavior is 275 // undefined." 276 if (Result->isFunctionType() && TypeQuals) { 277 // Get some location to point at, either the C or V location. 278 SourceLocation Loc; 279 if (TypeQuals & QualType::Const) 280 Loc = DS.getConstSpecLoc(); 281 else { 282 assert((TypeQuals & QualType::Volatile) && 283 "Has CV quals but not C or V?"); 284 Loc = DS.getVolatileSpecLoc(); 285 } 286 Diag(Loc, diag::warn_typecheck_function_qualifiers) 287 << Result << DS.getSourceRange(); 288 } 289 290 // C++ [dcl.ref]p1: 291 // Cv-qualified references are ill-formed except when the 292 // cv-qualifiers are introduced through the use of a typedef 293 // (7.1.3) or of a template type argument (14.3), in which 294 // case the cv-qualifiers are ignored. 295 // FIXME: Shouldn't we be checking SCS_typedef here? 296 if (DS.getTypeSpecType() == DeclSpec::TST_typename && 297 TypeQuals && Result->isReferenceType()) { 298 TypeQuals &= ~QualType::Const; 299 TypeQuals &= ~QualType::Volatile; 300 } 301 302 Result = Result.getQualifiedType(TypeQuals); 303 } 304 return Result; 305} 306 307static std::string getPrintableNameForEntity(DeclarationName Entity) { 308 if (Entity) 309 return Entity.getAsString(); 310 311 return "type name"; 312} 313 314/// \brief Build a pointer type. 315/// 316/// \param T The type to which we'll be building a pointer. 317/// 318/// \param Quals The cvr-qualifiers to be applied to the pointer type. 319/// 320/// \param Loc The location of the entity whose type involves this 321/// pointer type or, if there is no such entity, the location of the 322/// type that will have pointer type. 323/// 324/// \param Entity The name of the entity that involves the pointer 325/// type, if known. 326/// 327/// \returns A suitable pointer type, if there are no 328/// errors. Otherwise, returns a NULL type. 329QualType Sema::BuildPointerType(QualType T, unsigned Quals, 330 SourceLocation Loc, DeclarationName Entity) { 331 if (T->isReferenceType()) { 332 // C++ 8.3.2p4: There shall be no ... pointers to references ... 333 Diag(Loc, diag::err_illegal_decl_pointer_to_reference) 334 << getPrintableNameForEntity(Entity); 335 return QualType(); 336 } 337 338 // Enforce C99 6.7.3p2: "Types other than pointer types derived from 339 // object or incomplete types shall not be restrict-qualified." 340 if ((Quals & QualType::Restrict) && !T->isIncompleteOrObjectType()) { 341 Diag(Loc, diag::err_typecheck_invalid_restrict_invalid_pointee) 342 << T; 343 Quals &= ~QualType::Restrict; 344 } 345 346 // Build the pointer type. 347 return Context.getPointerType(T).getQualifiedType(Quals); 348} 349 350/// \brief Build a reference type. 351/// 352/// \param T The type to which we'll be building a reference. 353/// 354/// \param Quals The cvr-qualifiers to be applied to the reference type. 355/// 356/// \param Loc The location of the entity whose type involves this 357/// reference type or, if there is no such entity, the location of the 358/// type that will have reference type. 359/// 360/// \param Entity The name of the entity that involves the reference 361/// type, if known. 362/// 363/// \returns A suitable reference type, if there are no 364/// errors. Otherwise, returns a NULL type. 365QualType Sema::BuildReferenceType(QualType T, bool LValueRef, unsigned Quals, 366 SourceLocation Loc, DeclarationName Entity) { 367 if (LValueRef) { 368 if (const RValueReferenceType *R = T->getAsRValueReferenceType()) { 369 // C++0x [dcl.typedef]p9: If a typedef TD names a type that is a 370 // reference to a type T, and attempt to create the type "lvalue 371 // reference to cv TD" creates the type "lvalue reference to T". 372 // We use the qualifiers (restrict or none) of the original reference, 373 // not the new ones. This is consistent with GCC. 374 return Context.getLValueReferenceType(R->getPointeeType()). 375 getQualifiedType(T.getCVRQualifiers()); 376 } 377 } 378 if (T->isReferenceType()) { 379 // C++ [dcl.ref]p4: There shall be no references to references. 380 // 381 // According to C++ DR 106, references to references are only 382 // diagnosed when they are written directly (e.g., "int & &"), 383 // but not when they happen via a typedef: 384 // 385 // typedef int& intref; 386 // typedef intref& intref2; 387 // 388 // Parser::ParserDeclaratorInternal diagnoses the case where 389 // references are written directly; here, we handle the 390 // collapsing of references-to-references as described in C++ 391 // DR 106 and amended by C++ DR 540. 392 return T; 393 } 394 395 // C++ [dcl.ref]p1: 396 // A declarator that specifies the type “reference to cv void” 397 // is ill-formed. 398 if (T->isVoidType()) { 399 Diag(Loc, diag::err_reference_to_void); 400 return QualType(); 401 } 402 403 // Enforce C99 6.7.3p2: "Types other than pointer types derived from 404 // object or incomplete types shall not be restrict-qualified." 405 if ((Quals & QualType::Restrict) && !T->isIncompleteOrObjectType()) { 406 Diag(Loc, diag::err_typecheck_invalid_restrict_invalid_pointee) 407 << T; 408 Quals &= ~QualType::Restrict; 409 } 410 411 // C++ [dcl.ref]p1: 412 // [...] Cv-qualified references are ill-formed except when the 413 // cv-qualifiers are introduced through the use of a typedef 414 // (7.1.3) or of a template type argument (14.3), in which case 415 // the cv-qualifiers are ignored. 416 // 417 // We diagnose extraneous cv-qualifiers for the non-typedef, 418 // non-template type argument case within the parser. Here, we just 419 // ignore any extraneous cv-qualifiers. 420 Quals &= ~QualType::Const; 421 Quals &= ~QualType::Volatile; 422 423 // Handle restrict on references. 424 if (LValueRef) 425 return Context.getLValueReferenceType(T).getQualifiedType(Quals); 426 return Context.getRValueReferenceType(T).getQualifiedType(Quals); 427} 428 429/// \brief Build an array type. 430/// 431/// \param T The type of each element in the array. 432/// 433/// \param ASM C99 array size modifier (e.g., '*', 'static'). 434/// 435/// \param ArraySize Expression describing the size of the array. 436/// 437/// \param Quals The cvr-qualifiers to be applied to the array's 438/// element type. 439/// 440/// \param Loc The location of the entity whose type involves this 441/// array type or, if there is no such entity, the location of the 442/// type that will have array type. 443/// 444/// \param Entity The name of the entity that involves the array 445/// type, if known. 446/// 447/// \returns A suitable array type, if there are no errors. Otherwise, 448/// returns a NULL type. 449QualType Sema::BuildArrayType(QualType T, ArrayType::ArraySizeModifier ASM, 450 Expr *ArraySize, unsigned Quals, 451 SourceLocation Loc, DeclarationName Entity) { 452 // C99 6.7.5.2p1: If the element type is an incomplete or function type, 453 // reject it (e.g. void ary[7], struct foo ary[7], void ary[7]()) 454 if (RequireCompleteType(Loc, T, 455 diag::err_illegal_decl_array_incomplete_type)) 456 return QualType(); 457 458 if (T->isFunctionType()) { 459 Diag(Loc, diag::err_illegal_decl_array_of_functions) 460 << getPrintableNameForEntity(Entity); 461 return QualType(); 462 } 463 464 // C++ 8.3.2p4: There shall be no ... arrays of references ... 465 if (T->isReferenceType()) { 466 Diag(Loc, diag::err_illegal_decl_array_of_references) 467 << getPrintableNameForEntity(Entity); 468 return QualType(); 469 } 470 471 if (const RecordType *EltTy = T->getAsRecordType()) { 472 // If the element type is a struct or union that contains a variadic 473 // array, accept it as a GNU extension: C99 6.7.2.1p2. 474 if (EltTy->getDecl()->hasFlexibleArrayMember()) 475 Diag(Loc, diag::ext_flexible_array_in_array) << T; 476 } else if (T->isObjCInterfaceType()) { 477 Diag(Loc, diag::warn_objc_array_of_interfaces) << T; 478 } 479 480 // C99 6.7.5.2p1: The size expression shall have integer type. 481 if (ArraySize && !ArraySize->isTypeDependent() && 482 !ArraySize->getType()->isIntegerType()) { 483 Diag(ArraySize->getLocStart(), diag::err_array_size_non_int) 484 << ArraySize->getType() << ArraySize->getSourceRange(); 485 ArraySize->Destroy(Context); 486 return QualType(); 487 } 488 llvm::APSInt ConstVal(32); 489 if (!ArraySize) { 490 T = Context.getIncompleteArrayType(T, ASM, Quals); 491 } else if (ArraySize->isValueDependent()) { 492 T = Context.getDependentSizedArrayType(T, ArraySize, ASM, Quals); 493 } else if (!ArraySize->isIntegerConstantExpr(ConstVal, Context) || 494 (!T->isDependentType() && !T->isConstantSizeType())) { 495 // Per C99, a variable array is an array with either a non-constant 496 // size or an element type that has a non-constant-size 497 T = Context.getVariableArrayType(T, ArraySize, ASM, Quals); 498 } else { 499 // C99 6.7.5.2p1: If the expression is a constant expression, it shall 500 // have a value greater than zero. 501 if (ConstVal.isSigned()) { 502 if (ConstVal.isNegative()) { 503 Diag(ArraySize->getLocStart(), 504 diag::err_typecheck_negative_array_size) 505 << ArraySize->getSourceRange(); 506 return QualType(); 507 } else if (ConstVal == 0) { 508 // GCC accepts zero sized static arrays. 509 Diag(ArraySize->getLocStart(), diag::ext_typecheck_zero_array_size) 510 << ArraySize->getSourceRange(); 511 } 512 } 513 T = Context.getConstantArrayType(T, ConstVal, ASM, Quals); 514 } 515 // If this is not C99, extwarn about VLA's and C99 array size modifiers. 516 if (!getLangOptions().C99) { 517 if (ArraySize && !ArraySize->isTypeDependent() && 518 !ArraySize->isValueDependent() && 519 !ArraySize->isIntegerConstantExpr(Context)) 520 Diag(Loc, diag::ext_vla); 521 else if (ASM != ArrayType::Normal || Quals != 0) 522 Diag(Loc, diag::ext_c99_array_usage); 523 } 524 525 return T; 526} 527 528/// \brief Build a function type. 529/// 530/// This routine checks the function type according to C++ rules and 531/// under the assumption that the result type and parameter types have 532/// just been instantiated from a template. It therefore duplicates 533/// some of the behavior of GetTypeForDeclarator, but in a much 534/// simpler form that is only suitable for this narrow use case. 535/// 536/// \param T The return type of the function. 537/// 538/// \param ParamTypes The parameter types of the function. This array 539/// will be modified to account for adjustments to the types of the 540/// function parameters. 541/// 542/// \param NumParamTypes The number of parameter types in ParamTypes. 543/// 544/// \param Variadic Whether this is a variadic function type. 545/// 546/// \param Quals The cvr-qualifiers to be applied to the function type. 547/// 548/// \param Loc The location of the entity whose type involves this 549/// function type or, if there is no such entity, the location of the 550/// type that will have function type. 551/// 552/// \param Entity The name of the entity that involves the function 553/// type, if known. 554/// 555/// \returns A suitable function type, if there are no 556/// errors. Otherwise, returns a NULL type. 557QualType Sema::BuildFunctionType(QualType T, 558 QualType *ParamTypes, 559 unsigned NumParamTypes, 560 bool Variadic, unsigned Quals, 561 SourceLocation Loc, DeclarationName Entity) { 562 if (T->isArrayType() || T->isFunctionType()) { 563 Diag(Loc, diag::err_func_returning_array_function) << T; 564 return QualType(); 565 } 566 567 bool Invalid = false; 568 for (unsigned Idx = 0; Idx < NumParamTypes; ++Idx) { 569 QualType ParamType = adjustParameterType(ParamTypes[Idx]); 570 if (ParamType->isVoidType()) { 571 Diag(Loc, diag::err_param_with_void_type); 572 Invalid = true; 573 } 574 575 ParamTypes[Idx] = ParamType; 576 } 577 578 if (Invalid) 579 return QualType(); 580 581 return Context.getFunctionType(T, ParamTypes, NumParamTypes, Variadic, 582 Quals); 583} 584 585/// GetTypeForDeclarator - Convert the type for the specified 586/// declarator to Type instances. Skip the outermost Skip type 587/// objects. 588QualType Sema::GetTypeForDeclarator(Declarator &D, Scope *S, unsigned Skip) { 589 bool OmittedReturnType = false; 590 591 if (D.getContext() == Declarator::BlockLiteralContext 592 && Skip == 0 593 && !D.getDeclSpec().hasTypeSpecifier() 594 && (D.getNumTypeObjects() == 0 595 || (D.getNumTypeObjects() == 1 596 && D.getTypeObject(0).Kind == DeclaratorChunk::Function))) 597 OmittedReturnType = true; 598 599 // long long is a C99 feature. 600 if (!getLangOptions().C99 && !getLangOptions().CPlusPlus0x && 601 D.getDeclSpec().getTypeSpecWidth() == DeclSpec::TSW_longlong) 602 Diag(D.getDeclSpec().getTypeSpecWidthLoc(), diag::ext_longlong); 603 604 // Determine the type of the declarator. Not all forms of declarator 605 // have a type. 606 QualType T; 607 switch (D.getKind()) { 608 case Declarator::DK_Abstract: 609 case Declarator::DK_Normal: 610 case Declarator::DK_Operator: { 611 const DeclSpec &DS = D.getDeclSpec(); 612 if (OmittedReturnType) { 613 // We default to a dependent type initially. Can be modified by 614 // the first return statement. 615 T = Context.DependentTy; 616 } else { 617 T = ConvertDeclSpecToType(DS, D.getIdentifierLoc()); 618 if (T.isNull()) 619 return T; 620 } 621 break; 622 } 623 624 case Declarator::DK_Constructor: 625 case Declarator::DK_Destructor: 626 case Declarator::DK_Conversion: 627 // Constructors and destructors don't have return types. Use 628 // "void" instead. Conversion operators will check their return 629 // types separately. 630 T = Context.VoidTy; 631 break; 632 } 633 634 // The name we're declaring, if any. 635 DeclarationName Name; 636 if (D.getIdentifier()) 637 Name = D.getIdentifier(); 638 639 // Walk the DeclTypeInfo, building the recursive type as we go. 640 // DeclTypeInfos are ordered from the identifier out, which is 641 // opposite of what we want :). 642 for (unsigned i = Skip, e = D.getNumTypeObjects(); i != e; ++i) { 643 DeclaratorChunk &DeclType = D.getTypeObject(e-i-1+Skip); 644 switch (DeclType.Kind) { 645 default: assert(0 && "Unknown decltype!"); 646 case DeclaratorChunk::BlockPointer: 647 // If blocks are disabled, emit an error. 648 if (!LangOpts.Blocks) 649 Diag(DeclType.Loc, diag::err_blocks_disable); 650 651 if (DeclType.Cls.TypeQuals) 652 Diag(D.getIdentifierLoc(), diag::err_qualified_block_pointer_type); 653 if (!T.getTypePtr()->isFunctionType()) 654 Diag(D.getIdentifierLoc(), diag::err_nonfunction_block_type); 655 else 656 T = Context.getBlockPointerType(T); 657 break; 658 case DeclaratorChunk::Pointer: 659 T = BuildPointerType(T, DeclType.Ptr.TypeQuals, DeclType.Loc, Name); 660 break; 661 case DeclaratorChunk::Reference: 662 T = BuildReferenceType(T, DeclType.Ref.LValueRef, 663 DeclType.Ref.HasRestrict ? QualType::Restrict : 0, 664 DeclType.Loc, Name); 665 break; 666 case DeclaratorChunk::Array: { 667 DeclaratorChunk::ArrayTypeInfo &ATI = DeclType.Arr; 668 Expr *ArraySize = static_cast<Expr*>(ATI.NumElts); 669 ArrayType::ArraySizeModifier ASM; 670 if (ATI.isStar) 671 ASM = ArrayType::Star; 672 else if (ATI.hasStatic) 673 ASM = ArrayType::Static; 674 else 675 ASM = ArrayType::Normal; 676 T = BuildArrayType(T, ASM, ArraySize, ATI.TypeQuals, DeclType.Loc, Name); 677 break; 678 } 679 case DeclaratorChunk::Function: { 680 // If the function declarator has a prototype (i.e. it is not () and 681 // does not have a K&R-style identifier list), then the arguments are part 682 // of the type, otherwise the argument list is (). 683 const DeclaratorChunk::FunctionTypeInfo &FTI = DeclType.Fun; 684 685 // C99 6.7.5.3p1: The return type may not be a function or array type. 686 if (T->isArrayType() || T->isFunctionType()) { 687 Diag(DeclType.Loc, diag::err_func_returning_array_function) << T; 688 T = Context.IntTy; 689 D.setInvalidType(true); 690 } 691 692 if (FTI.NumArgs == 0) { 693 if (getLangOptions().CPlusPlus) { 694 // C++ 8.3.5p2: If the parameter-declaration-clause is empty, the 695 // function takes no arguments. 696 T = Context.getFunctionType(T, NULL, 0, FTI.isVariadic,FTI.TypeQuals); 697 } else if (FTI.isVariadic) { 698 // We allow a zero-parameter variadic function in C if the 699 // function is marked with the "overloadable" 700 // attribute. Scan for this attribute now. 701 bool Overloadable = false; 702 for (const AttributeList *Attrs = D.getAttributes(); 703 Attrs; Attrs = Attrs->getNext()) { 704 if (Attrs->getKind() == AttributeList::AT_overloadable) { 705 Overloadable = true; 706 break; 707 } 708 } 709 710 if (!Overloadable) 711 Diag(FTI.getEllipsisLoc(), diag::err_ellipsis_first_arg); 712 T = Context.getFunctionType(T, NULL, 0, FTI.isVariadic, 0); 713 } else { 714 // Simple void foo(), where the incoming T is the result type. 715 T = Context.getFunctionNoProtoType(T); 716 } 717 } else if (FTI.ArgInfo[0].Param == 0) { 718 // C99 6.7.5.3p3: Reject int(x,y,z) when it's not a function definition. 719 Diag(FTI.ArgInfo[0].IdentLoc, diag::err_ident_list_in_fn_declaration); 720 } else { 721 // Otherwise, we have a function with an argument list that is 722 // potentially variadic. 723 llvm::SmallVector<QualType, 16> ArgTys; 724 725 for (unsigned i = 0, e = FTI.NumArgs; i != e; ++i) { 726 ParmVarDecl *Param = 727 cast<ParmVarDecl>(FTI.ArgInfo[i].Param.getAs<Decl>()); 728 QualType ArgTy = Param->getType(); 729 assert(!ArgTy.isNull() && "Couldn't parse type?"); 730 731 // Adjust the parameter type. 732 assert((ArgTy == adjustParameterType(ArgTy)) && "Unadjusted type?"); 733 734 // Look for 'void'. void is allowed only as a single argument to a 735 // function with no other parameters (C99 6.7.5.3p10). We record 736 // int(void) as a FunctionProtoType with an empty argument list. 737 if (ArgTy->isVoidType()) { 738 // If this is something like 'float(int, void)', reject it. 'void' 739 // is an incomplete type (C99 6.2.5p19) and function decls cannot 740 // have arguments of incomplete type. 741 if (FTI.NumArgs != 1 || FTI.isVariadic) { 742 Diag(DeclType.Loc, diag::err_void_only_param); 743 ArgTy = Context.IntTy; 744 Param->setType(ArgTy); 745 } else if (FTI.ArgInfo[i].Ident) { 746 // Reject, but continue to parse 'int(void abc)'. 747 Diag(FTI.ArgInfo[i].IdentLoc, 748 diag::err_param_with_void_type); 749 ArgTy = Context.IntTy; 750 Param->setType(ArgTy); 751 } else { 752 // Reject, but continue to parse 'float(const void)'. 753 if (ArgTy.getCVRQualifiers()) 754 Diag(DeclType.Loc, diag::err_void_param_qualified); 755 756 // Do not add 'void' to the ArgTys list. 757 break; 758 } 759 } else if (!FTI.hasPrototype) { 760 if (ArgTy->isPromotableIntegerType()) { 761 ArgTy = Context.IntTy; 762 } else if (const BuiltinType* BTy = ArgTy->getAsBuiltinType()) { 763 if (BTy->getKind() == BuiltinType::Float) 764 ArgTy = Context.DoubleTy; 765 } 766 } 767 768 ArgTys.push_back(ArgTy); 769 } 770 T = Context.getFunctionType(T, &ArgTys[0], ArgTys.size(), 771 FTI.isVariadic, FTI.TypeQuals); 772 } 773 break; 774 } 775 case DeclaratorChunk::MemberPointer: 776 // The scope spec must refer to a class, or be dependent. 777 DeclContext *DC = computeDeclContext(DeclType.Mem.Scope()); 778 QualType ClsType; 779 // FIXME: Extend for dependent types when it's actually supported. 780 // See ActOnCXXNestedNameSpecifier. 781 if (CXXRecordDecl *RD = dyn_cast_or_null<CXXRecordDecl>(DC)) { 782 ClsType = Context.getTagDeclType(RD); 783 } else { 784 if (DC) { 785 Diag(DeclType.Mem.Scope().getBeginLoc(), 786 diag::err_illegal_decl_mempointer_in_nonclass) 787 << (D.getIdentifier() ? D.getIdentifier()->getName() : "type name") 788 << DeclType.Mem.Scope().getRange(); 789 } 790 D.setInvalidType(true); 791 ClsType = Context.IntTy; 792 } 793 794 // C++ 8.3.3p3: A pointer to member shall not pointer to ... a member 795 // with reference type, or "cv void." 796 if (T->isReferenceType()) { 797 Diag(DeclType.Loc, diag::err_illegal_decl_pointer_to_reference) 798 << (D.getIdentifier() ? D.getIdentifier()->getName() : "type name"); 799 D.setInvalidType(true); 800 T = Context.IntTy; 801 } 802 if (T->isVoidType()) { 803 Diag(DeclType.Loc, diag::err_illegal_decl_mempointer_to_void) 804 << (D.getIdentifier() ? D.getIdentifier()->getName() : "type name"); 805 T = Context.IntTy; 806 } 807 808 // Enforce C99 6.7.3p2: "Types other than pointer types derived from 809 // object or incomplete types shall not be restrict-qualified." 810 if ((DeclType.Mem.TypeQuals & QualType::Restrict) && 811 !T->isIncompleteOrObjectType()) { 812 Diag(DeclType.Loc, diag::err_typecheck_invalid_restrict_invalid_pointee) 813 << T; 814 DeclType.Mem.TypeQuals &= ~QualType::Restrict; 815 } 816 817 T = Context.getMemberPointerType(T, ClsType.getTypePtr()). 818 getQualifiedType(DeclType.Mem.TypeQuals); 819 820 break; 821 } 822 823 if (T.isNull()) { 824 D.setInvalidType(true); 825 T = Context.IntTy; 826 } 827 828 // See if there are any attributes on this declarator chunk. 829 if (const AttributeList *AL = DeclType.getAttrs()) 830 ProcessTypeAttributeList(T, AL); 831 } 832 833 if (getLangOptions().CPlusPlus && T->isFunctionType()) { 834 const FunctionProtoType *FnTy = T->getAsFunctionProtoType(); 835 assert(FnTy && "Why oh why is there not a FunctionProtoType here ?"); 836 837 // C++ 8.3.5p4: A cv-qualifier-seq shall only be part of the function type 838 // for a nonstatic member function, the function type to which a pointer 839 // to member refers, or the top-level function type of a function typedef 840 // declaration. 841 if (FnTy->getTypeQuals() != 0 && 842 D.getDeclSpec().getStorageClassSpec() != DeclSpec::SCS_typedef && 843 ((D.getContext() != Declarator::MemberContext && 844 (!D.getCXXScopeSpec().isSet() || 845 !computeDeclContext(D.getCXXScopeSpec())->isRecord())) || 846 D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_static)) { 847 if (D.isFunctionDeclarator()) 848 Diag(D.getIdentifierLoc(), diag::err_invalid_qualified_function_type); 849 else 850 Diag(D.getIdentifierLoc(), 851 diag::err_invalid_qualified_typedef_function_type_use); 852 853 // Strip the cv-quals from the type. 854 T = Context.getFunctionType(FnTy->getResultType(), FnTy->arg_type_begin(), 855 FnTy->getNumArgs(), FnTy->isVariadic(), 0); 856 } 857 } 858 859 // If there were any type attributes applied to the decl itself (not the 860 // type, apply the type attribute to the type!) 861 if (const AttributeList *Attrs = D.getAttributes()) 862 ProcessTypeAttributeList(T, Attrs); 863 864 return T; 865} 866 867/// ObjCGetTypeForMethodDefinition - Builds the type for a method definition 868/// declarator 869QualType Sema::ObjCGetTypeForMethodDefinition(DeclPtrTy D) { 870 ObjCMethodDecl *MDecl = cast<ObjCMethodDecl>(D.getAs<Decl>()); 871 QualType T = MDecl->getResultType(); 872 llvm::SmallVector<QualType, 16> ArgTys; 873 874 // Add the first two invisible argument types for self and _cmd. 875 if (MDecl->isInstanceMethod()) { 876 QualType selfTy = Context.getObjCInterfaceType(MDecl->getClassInterface()); 877 selfTy = Context.getPointerType(selfTy); 878 ArgTys.push_back(selfTy); 879 } else 880 ArgTys.push_back(Context.getObjCIdType()); 881 ArgTys.push_back(Context.getObjCSelType()); 882 883 for (ObjCMethodDecl::param_iterator PI = MDecl->param_begin(), 884 E = MDecl->param_end(); PI != E; ++PI) { 885 QualType ArgTy = (*PI)->getType(); 886 assert(!ArgTy.isNull() && "Couldn't parse type?"); 887 ArgTy = adjustParameterType(ArgTy); 888 ArgTys.push_back(ArgTy); 889 } 890 T = Context.getFunctionType(T, &ArgTys[0], ArgTys.size(), 891 MDecl->isVariadic(), 0); 892 return T; 893} 894 895/// UnwrapSimilarPointerTypes - If T1 and T2 are pointer types that 896/// may be similar (C++ 4.4), replaces T1 and T2 with the type that 897/// they point to and return true. If T1 and T2 aren't pointer types 898/// or pointer-to-member types, or if they are not similar at this 899/// level, returns false and leaves T1 and T2 unchanged. Top-level 900/// qualifiers on T1 and T2 are ignored. This function will typically 901/// be called in a loop that successively "unwraps" pointer and 902/// pointer-to-member types to compare them at each level. 903bool Sema::UnwrapSimilarPointerTypes(QualType& T1, QualType& T2) { 904 const PointerType *T1PtrType = T1->getAsPointerType(), 905 *T2PtrType = T2->getAsPointerType(); 906 if (T1PtrType && T2PtrType) { 907 T1 = T1PtrType->getPointeeType(); 908 T2 = T2PtrType->getPointeeType(); 909 return true; 910 } 911 912 const MemberPointerType *T1MPType = T1->getAsMemberPointerType(), 913 *T2MPType = T2->getAsMemberPointerType(); 914 if (T1MPType && T2MPType && 915 Context.getCanonicalType(T1MPType->getClass()) == 916 Context.getCanonicalType(T2MPType->getClass())) { 917 T1 = T1MPType->getPointeeType(); 918 T2 = T2MPType->getPointeeType(); 919 return true; 920 } 921 return false; 922} 923 924Sema::TypeResult Sema::ActOnTypeName(Scope *S, Declarator &D) { 925 // C99 6.7.6: Type names have no identifier. This is already validated by 926 // the parser. 927 assert(D.getIdentifier() == 0 && "Type name should have no identifier!"); 928 929 QualType T = GetTypeForDeclarator(D, S); 930 if (T.isNull()) 931 return true; 932 933 // Check that there are no default arguments (C++ only). 934 if (getLangOptions().CPlusPlus) 935 CheckExtraCXXDefaultArguments(D); 936 937 return T.getAsOpaquePtr(); 938} 939 940 941 942//===----------------------------------------------------------------------===// 943// Type Attribute Processing 944//===----------------------------------------------------------------------===// 945 946/// HandleAddressSpaceTypeAttribute - Process an address_space attribute on the 947/// specified type. The attribute contains 1 argument, the id of the address 948/// space for the type. 949static void HandleAddressSpaceTypeAttribute(QualType &Type, 950 const AttributeList &Attr, Sema &S){ 951 // If this type is already address space qualified, reject it. 952 // Clause 6.7.3 - Type qualifiers: "No type shall be qualified by qualifiers 953 // for two or more different address spaces." 954 if (Type.getAddressSpace()) { 955 S.Diag(Attr.getLoc(), diag::err_attribute_address_multiple_qualifiers); 956 return; 957 } 958 959 // Check the attribute arguments. 960 if (Attr.getNumArgs() != 1) { 961 S.Diag(Attr.getLoc(), diag::err_attribute_wrong_number_arguments) << 1; 962 return; 963 } 964 Expr *ASArgExpr = static_cast<Expr *>(Attr.getArg(0)); 965 llvm::APSInt addrSpace(32); 966 if (!ASArgExpr->isIntegerConstantExpr(addrSpace, S.Context)) { 967 S.Diag(Attr.getLoc(), diag::err_attribute_address_space_not_int) 968 << ASArgExpr->getSourceRange(); 969 return; 970 } 971 972 unsigned ASIdx = static_cast<unsigned>(addrSpace.getZExtValue()); 973 Type = S.Context.getAddrSpaceQualType(Type, ASIdx); 974} 975 976/// HandleObjCGCTypeAttribute - Process an objc's gc attribute on the 977/// specified type. The attribute contains 1 argument, weak or strong. 978static void HandleObjCGCTypeAttribute(QualType &Type, 979 const AttributeList &Attr, Sema &S) { 980 if (Type.getObjCGCAttr() != QualType::GCNone) { 981 S.Diag(Attr.getLoc(), diag::err_attribute_multiple_objc_gc); 982 return; 983 } 984 985 // Check the attribute arguments. 986 if (!Attr.getParameterName()) { 987 S.Diag(Attr.getLoc(), diag::err_attribute_argument_n_not_string) 988 << "objc_gc" << 1; 989 return; 990 } 991 QualType::GCAttrTypes GCAttr; 992 if (Attr.getNumArgs() != 0) { 993 S.Diag(Attr.getLoc(), diag::err_attribute_wrong_number_arguments) << 1; 994 return; 995 } 996 if (Attr.getParameterName()->isStr("weak")) 997 GCAttr = QualType::Weak; 998 else if (Attr.getParameterName()->isStr("strong")) 999 GCAttr = QualType::Strong; 1000 else { 1001 S.Diag(Attr.getLoc(), diag::warn_attribute_type_not_supported) 1002 << "objc_gc" << Attr.getParameterName(); 1003 return; 1004 } 1005 1006 Type = S.Context.getObjCGCQualType(Type, GCAttr); 1007} 1008 1009void Sema::ProcessTypeAttributeList(QualType &Result, const AttributeList *AL) { 1010 // Scan through and apply attributes to this type where it makes sense. Some 1011 // attributes (such as __address_space__, __vector_size__, etc) apply to the 1012 // type, but others can be present in the type specifiers even though they 1013 // apply to the decl. Here we apply type attributes and ignore the rest. 1014 for (; AL; AL = AL->getNext()) { 1015 // If this is an attribute we can handle, do so now, otherwise, add it to 1016 // the LeftOverAttrs list for rechaining. 1017 switch (AL->getKind()) { 1018 default: break; 1019 case AttributeList::AT_address_space: 1020 HandleAddressSpaceTypeAttribute(Result, *AL, *this); 1021 break; 1022 case AttributeList::AT_objc_gc: 1023 HandleObjCGCTypeAttribute(Result, *AL, *this); 1024 break; 1025 } 1026 } 1027} 1028 1029/// @brief Ensure that the type T is a complete type. 1030/// 1031/// This routine checks whether the type @p T is complete in any 1032/// context where a complete type is required. If @p T is a complete 1033/// type, returns false. If @p T is a class template specialization, 1034/// this routine then attempts to perform class template 1035/// instantiation. If instantiation fails, or if @p T is incomplete 1036/// and cannot be completed, issues the diagnostic @p diag (giving it 1037/// the type @p T) and returns true. 1038/// 1039/// @param Loc The location in the source that the incomplete type 1040/// diagnostic should refer to. 1041/// 1042/// @param T The type that this routine is examining for completeness. 1043/// 1044/// @param diag The diagnostic value (e.g., 1045/// @c diag::err_typecheck_decl_incomplete_type) that will be used 1046/// for the error message if @p T is incomplete. 1047/// 1048/// @param Range1 An optional range in the source code that will be a 1049/// part of the "incomplete type" error message. 1050/// 1051/// @param Range2 An optional range in the source code that will be a 1052/// part of the "incomplete type" error message. 1053/// 1054/// @param PrintType If non-NULL, the type that should be printed 1055/// instead of @p T. This parameter should be used when the type that 1056/// we're checking for incompleteness isn't the type that should be 1057/// displayed to the user, e.g., when T is a type and PrintType is a 1058/// pointer to T. 1059/// 1060/// @returns @c true if @p T is incomplete and a diagnostic was emitted, 1061/// @c false otherwise. 1062bool Sema::RequireCompleteType(SourceLocation Loc, QualType T, unsigned diag, 1063 SourceRange Range1, SourceRange Range2, 1064 QualType PrintType) { 1065 // If we have a complete type, we're done. 1066 if (!T->isIncompleteType()) 1067 return false; 1068 1069 // If we have a class template specialization or a class member of a 1070 // class template specialization, try to instantiate it. 1071 if (const RecordType *Record = T->getAsRecordType()) { 1072 if (ClassTemplateSpecializationDecl *ClassTemplateSpec 1073 = dyn_cast<ClassTemplateSpecializationDecl>(Record->getDecl())) { 1074 if (ClassTemplateSpec->getSpecializationKind() == TSK_Undeclared) { 1075 // Update the class template specialization's location to 1076 // refer to the point of instantiation. 1077 if (Loc.isValid()) 1078 ClassTemplateSpec->setLocation(Loc); 1079 return InstantiateClassTemplateSpecialization(ClassTemplateSpec, 1080 /*ExplicitInstantiation=*/false); 1081 } 1082 } else if (CXXRecordDecl *Rec 1083 = dyn_cast<CXXRecordDecl>(Record->getDecl())) { 1084 if (CXXRecordDecl *Pattern = Rec->getInstantiatedFromMemberClass()) { 1085 // Find the class template specialization that surrounds this 1086 // member class. 1087 ClassTemplateSpecializationDecl *Spec = 0; 1088 for (DeclContext *Parent = Rec->getDeclContext(); 1089 Parent && !Spec; Parent = Parent->getParent()) 1090 Spec = dyn_cast<ClassTemplateSpecializationDecl>(Parent); 1091 assert(Spec && "Not a member of a class template specialization?"); 1092 return InstantiateClass(Loc, Rec, Pattern, 1093 Spec->getTemplateArgs(), 1094 Spec->getNumTemplateArgs()); 1095 } 1096 } 1097 } 1098 1099 if (PrintType.isNull()) 1100 PrintType = T; 1101 1102 // We have an incomplete type. Produce a diagnostic. 1103 Diag(Loc, diag) << PrintType << Range1 << Range2; 1104 1105 // If the type was a forward declaration of a class/struct/union 1106 // type, produce 1107 const TagType *Tag = 0; 1108 if (const RecordType *Record = T->getAsRecordType()) 1109 Tag = Record; 1110 else if (const EnumType *Enum = T->getAsEnumType()) 1111 Tag = Enum; 1112 1113 if (Tag && !Tag->getDecl()->isInvalidDecl()) 1114 Diag(Tag->getDecl()->getLocation(), 1115 Tag->isBeingDefined() ? diag::note_type_being_defined 1116 : diag::note_forward_declaration) 1117 << QualType(Tag, 0); 1118 1119 return true; 1120} 1121 1122/// \brief Retrieve a version of the type 'T' that is qualified by the 1123/// nested-name-specifier contained in SS. 1124QualType Sema::getQualifiedNameType(const CXXScopeSpec &SS, QualType T) { 1125 if (!SS.isSet() || SS.isInvalid() || T.isNull()) 1126 return T; 1127 1128 NestedNameSpecifier *NNS 1129 = static_cast<NestedNameSpecifier *>(SS.getScopeRep()); 1130 return Context.getQualifiedNameType(NNS, T); 1131} 1132