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1 //===--- SemaExprObjC.cpp - Semantic Analysis for ObjC 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 Objective-C expressions.
11 //
12 //===----------------------------------------------------------------------===//
13 
14 #include "clang/Sema/SemaInternal.h"
15 #include "clang/Sema/Lookup.h"
16 #include "clang/Sema/Scope.h"
17 #include "clang/Sema/ScopeInfo.h"
18 #include "clang/Sema/Initialization.h"
19 #include "clang/Analysis/DomainSpecific/CocoaConventions.h"
20 #include "clang/Edit/Rewriters.h"
21 #include "clang/Edit/Commit.h"
22 #include "clang/AST/ASTContext.h"
23 #include "clang/AST/DeclObjC.h"
24 #include "clang/AST/ExprObjC.h"
25 #include "clang/AST/StmtVisitor.h"
26 #include "clang/AST/TypeLoc.h"
27 #include "llvm/ADT/SmallString.h"
28 #include "clang/Lex/Preprocessor.h"
29 
30 using namespace clang;
31 using namespace sema;
32 using llvm::makeArrayRef;
33 
ParseObjCStringLiteral(SourceLocation * AtLocs,Expr ** strings,unsigned NumStrings)34 ExprResult Sema::ParseObjCStringLiteral(SourceLocation *AtLocs,
35                                         Expr **strings,
36                                         unsigned NumStrings) {
37   StringLiteral **Strings = reinterpret_cast<StringLiteral**>(strings);
38 
39   // Most ObjC strings are formed out of a single piece.  However, we *can*
40   // have strings formed out of multiple @ strings with multiple pptokens in
41   // each one, e.g. @"foo" "bar" @"baz" "qux"   which need to be turned into one
42   // StringLiteral for ObjCStringLiteral to hold onto.
43   StringLiteral *S = Strings[0];
44 
45   // If we have a multi-part string, merge it all together.
46   if (NumStrings != 1) {
47     // Concatenate objc strings.
48     SmallString<128> StrBuf;
49     SmallVector<SourceLocation, 8> StrLocs;
50 
51     for (unsigned i = 0; i != NumStrings; ++i) {
52       S = Strings[i];
53 
54       // ObjC strings can't be wide or UTF.
55       if (!S->isAscii()) {
56         Diag(S->getLocStart(), diag::err_cfstring_literal_not_string_constant)
57           << S->getSourceRange();
58         return true;
59       }
60 
61       // Append the string.
62       StrBuf += S->getString();
63 
64       // Get the locations of the string tokens.
65       StrLocs.append(S->tokloc_begin(), S->tokloc_end());
66     }
67 
68     // Create the aggregate string with the appropriate content and location
69     // information.
70     S = StringLiteral::Create(Context, StrBuf,
71                               StringLiteral::Ascii, /*Pascal=*/false,
72                               Context.getPointerType(Context.CharTy),
73                               &StrLocs[0], StrLocs.size());
74   }
75 
76   return BuildObjCStringLiteral(AtLocs[0], S);
77 }
78 
BuildObjCStringLiteral(SourceLocation AtLoc,StringLiteral * S)79 ExprResult Sema::BuildObjCStringLiteral(SourceLocation AtLoc, StringLiteral *S){
80   // Verify that this composite string is acceptable for ObjC strings.
81   if (CheckObjCString(S))
82     return true;
83 
84   // Initialize the constant string interface lazily. This assumes
85   // the NSString interface is seen in this translation unit. Note: We
86   // don't use NSConstantString, since the runtime team considers this
87   // interface private (even though it appears in the header files).
88   QualType Ty = Context.getObjCConstantStringInterface();
89   if (!Ty.isNull()) {
90     Ty = Context.getObjCObjectPointerType(Ty);
91   } else if (getLangOpts().NoConstantCFStrings) {
92     IdentifierInfo *NSIdent=0;
93     std::string StringClass(getLangOpts().ObjCConstantStringClass);
94 
95     if (StringClass.empty())
96       NSIdent = &Context.Idents.get("NSConstantString");
97     else
98       NSIdent = &Context.Idents.get(StringClass);
99 
100     NamedDecl *IF = LookupSingleName(TUScope, NSIdent, AtLoc,
101                                      LookupOrdinaryName);
102     if (ObjCInterfaceDecl *StrIF = dyn_cast_or_null<ObjCInterfaceDecl>(IF)) {
103       Context.setObjCConstantStringInterface(StrIF);
104       Ty = Context.getObjCConstantStringInterface();
105       Ty = Context.getObjCObjectPointerType(Ty);
106     } else {
107       // If there is no NSConstantString interface defined then treat this
108       // as error and recover from it.
109       Diag(S->getLocStart(), diag::err_no_nsconstant_string_class) << NSIdent
110         << S->getSourceRange();
111       Ty = Context.getObjCIdType();
112     }
113   } else {
114     IdentifierInfo *NSIdent = NSAPIObj->getNSClassId(NSAPI::ClassId_NSString);
115     NamedDecl *IF = LookupSingleName(TUScope, NSIdent, AtLoc,
116                                      LookupOrdinaryName);
117     if (ObjCInterfaceDecl *StrIF = dyn_cast_or_null<ObjCInterfaceDecl>(IF)) {
118       Context.setObjCConstantStringInterface(StrIF);
119       Ty = Context.getObjCConstantStringInterface();
120       Ty = Context.getObjCObjectPointerType(Ty);
121     } else {
122       // If there is no NSString interface defined, implicitly declare
123       // a @class NSString; and use that instead. This is to make sure
124       // type of an NSString literal is represented correctly, instead of
125       // being an 'id' type.
126       Ty = Context.getObjCNSStringType();
127       if (Ty.isNull()) {
128         ObjCInterfaceDecl *NSStringIDecl =
129           ObjCInterfaceDecl::Create (Context,
130                                      Context.getTranslationUnitDecl(),
131                                      SourceLocation(), NSIdent,
132                                      0, SourceLocation());
133         Ty = Context.getObjCInterfaceType(NSStringIDecl);
134         Context.setObjCNSStringType(Ty);
135       }
136       Ty = Context.getObjCObjectPointerType(Ty);
137     }
138   }
139 
140   return new (Context) ObjCStringLiteral(S, Ty, AtLoc);
141 }
142 
143 /// \brief Retrieve the NSNumber factory method that should be used to create
144 /// an Objective-C literal for the given type.
getNSNumberFactoryMethod(Sema & S,SourceLocation Loc,QualType NumberType,bool isLiteral=false,SourceRange R=SourceRange ())145 static ObjCMethodDecl *getNSNumberFactoryMethod(Sema &S, SourceLocation Loc,
146                                                 QualType NumberType,
147                                                 bool isLiteral = false,
148                                                 SourceRange R = SourceRange()) {
149   llvm::Optional<NSAPI::NSNumberLiteralMethodKind> Kind
150     = S.NSAPIObj->getNSNumberFactoryMethodKind(NumberType);
151 
152   if (!Kind) {
153     if (isLiteral) {
154       S.Diag(Loc, diag::err_invalid_nsnumber_type)
155         << NumberType << R;
156     }
157     return 0;
158   }
159 
160   // If we already looked up this method, we're done.
161   if (S.NSNumberLiteralMethods[*Kind])
162     return S.NSNumberLiteralMethods[*Kind];
163 
164   Selector Sel = S.NSAPIObj->getNSNumberLiteralSelector(*Kind,
165                                                         /*Instance=*/false);
166 
167   ASTContext &CX = S.Context;
168 
169   // Look up the NSNumber class, if we haven't done so already. It's cached
170   // in the Sema instance.
171   if (!S.NSNumberDecl) {
172     IdentifierInfo *NSNumberId = S.NSAPIObj->getNSClassId(NSAPI::ClassId_NSNumber);
173     NamedDecl *IF = S.LookupSingleName(S.TUScope, NSNumberId,
174                                        Loc, Sema::LookupOrdinaryName);
175     S.NSNumberDecl = dyn_cast_or_null<ObjCInterfaceDecl>(IF);
176     if (!S.NSNumberDecl) {
177       if (S.getLangOpts().DebuggerObjCLiteral) {
178         // Create a stub definition of NSNumber.
179         S.NSNumberDecl =  ObjCInterfaceDecl::Create (CX,
180                                                      CX.getTranslationUnitDecl(),
181                                                      SourceLocation(),  NSNumberId,
182                                                      0, SourceLocation());
183       } else {
184         // Otherwise, require a declaration of NSNumber.
185         S.Diag(Loc, diag::err_undeclared_nsnumber);
186         return 0;
187       }
188     } else if (!S.NSNumberDecl->hasDefinition()) {
189       S.Diag(Loc, diag::err_undeclared_nsnumber);
190       return 0;
191     }
192 
193     // generate the pointer to NSNumber type.
194     S.NSNumberPointer = CX.getObjCObjectPointerType(CX.getObjCInterfaceType(S.NSNumberDecl));
195   }
196 
197   // Look for the appropriate method within NSNumber.
198   ObjCMethodDecl *Method = S.NSNumberDecl->lookupClassMethod(Sel);;
199   if (!Method && S.getLangOpts().DebuggerObjCLiteral) {
200     // create a stub definition this NSNumber factory method.
201     TypeSourceInfo *ResultTInfo = 0;
202     Method = ObjCMethodDecl::Create(CX, SourceLocation(), SourceLocation(), Sel,
203                                     S.NSNumberPointer, ResultTInfo, S.NSNumberDecl,
204                                     /*isInstance=*/false, /*isVariadic=*/false,
205                                     /*isSynthesized=*/false,
206                                     /*isImplicitlyDeclared=*/true,
207                                     /*isDefined=*/false, ObjCMethodDecl::Required,
208                                     /*HasRelatedResultType=*/false);
209     ParmVarDecl *value = ParmVarDecl::Create(S.Context, Method,
210                                              SourceLocation(), SourceLocation(),
211                                              &CX.Idents.get("value"),
212                                              NumberType, /*TInfo=*/0, SC_None, SC_None, 0);
213     Method->setMethodParams(S.Context, value, ArrayRef<SourceLocation>());
214   }
215 
216   if (!Method) {
217     S.Diag(Loc, diag::err_undeclared_nsnumber_method) << Sel;
218     return 0;
219   }
220 
221   // Make sure the return type is reasonable.
222   if (!Method->getResultType()->isObjCObjectPointerType()) {
223     S.Diag(Loc, diag::err_objc_literal_method_sig)
224       << Sel;
225     S.Diag(Method->getLocation(), diag::note_objc_literal_method_return)
226       << Method->getResultType();
227     return 0;
228   }
229 
230   // Note: if the parameter type is out-of-line, we'll catch it later in the
231   // implicit conversion.
232 
233   S.NSNumberLiteralMethods[*Kind] = Method;
234   return Method;
235 }
236 
237 /// BuildObjCNumericLiteral - builds an ObjCBoxedExpr AST node for the
238 /// numeric literal expression. Type of the expression will be "NSNumber *".
BuildObjCNumericLiteral(SourceLocation AtLoc,Expr * Number)239 ExprResult Sema::BuildObjCNumericLiteral(SourceLocation AtLoc, Expr *Number) {
240   // compute the effective range of the literal, including the leading '@'.
241   SourceRange SR(AtLoc, Number->getSourceRange().getEnd());
242 
243   // Determine the type of the literal.
244   QualType NumberType = Number->getType();
245   if (CharacterLiteral *Char = dyn_cast<CharacterLiteral>(Number)) {
246     // In C, character literals have type 'int'. That's not the type we want
247     // to use to determine the Objective-c literal kind.
248     switch (Char->getKind()) {
249     case CharacterLiteral::Ascii:
250       NumberType = Context.CharTy;
251       break;
252 
253     case CharacterLiteral::Wide:
254       NumberType = Context.getWCharType();
255       break;
256 
257     case CharacterLiteral::UTF16:
258       NumberType = Context.Char16Ty;
259       break;
260 
261     case CharacterLiteral::UTF32:
262       NumberType = Context.Char32Ty;
263       break;
264     }
265   }
266 
267   // Look for the appropriate method within NSNumber.
268   // Construct the literal.
269   ObjCMethodDecl *Method = getNSNumberFactoryMethod(*this, AtLoc, NumberType,
270                                                     true, Number->getSourceRange());
271   if (!Method)
272     return ExprError();
273 
274   // Convert the number to the type that the parameter expects.
275   QualType ArgType = Method->param_begin()[0]->getType();
276   ExprResult ConvertedNumber = PerformImplicitConversion(Number, ArgType,
277                                                          AA_Sending);
278   if (ConvertedNumber.isInvalid())
279     return ExprError();
280   Number = ConvertedNumber.get();
281 
282   return MaybeBindToTemporary(
283            new (Context) ObjCBoxedExpr(Number, NSNumberPointer, Method, SR));
284 }
285 
ActOnObjCBoolLiteral(SourceLocation AtLoc,SourceLocation ValueLoc,bool Value)286 ExprResult Sema::ActOnObjCBoolLiteral(SourceLocation AtLoc,
287                                       SourceLocation ValueLoc,
288                                       bool Value) {
289   ExprResult Inner;
290   if (getLangOpts().CPlusPlus) {
291     Inner = ActOnCXXBoolLiteral(ValueLoc, Value? tok::kw_true : tok::kw_false);
292   } else {
293     // C doesn't actually have a way to represent literal values of type
294     // _Bool. So, we'll use 0/1 and implicit cast to _Bool.
295     Inner = ActOnIntegerConstant(ValueLoc, Value? 1 : 0);
296     Inner = ImpCastExprToType(Inner.get(), Context.BoolTy,
297                               CK_IntegralToBoolean);
298   }
299 
300   return BuildObjCNumericLiteral(AtLoc, Inner.get());
301 }
302 
303 /// \brief Check that the given expression is a valid element of an Objective-C
304 /// collection literal.
CheckObjCCollectionLiteralElement(Sema & S,Expr * Element,QualType T)305 static ExprResult CheckObjCCollectionLiteralElement(Sema &S, Expr *Element,
306                                                     QualType T) {
307   // If the expression is type-dependent, there's nothing for us to do.
308   if (Element->isTypeDependent())
309     return Element;
310 
311   ExprResult Result = S.CheckPlaceholderExpr(Element);
312   if (Result.isInvalid())
313     return ExprError();
314   Element = Result.get();
315 
316   // In C++, check for an implicit conversion to an Objective-C object pointer
317   // type.
318   if (S.getLangOpts().CPlusPlus && Element->getType()->isRecordType()) {
319     InitializedEntity Entity
320       = InitializedEntity::InitializeParameter(S.Context, T, /*Consumed=*/false);
321     InitializationKind Kind
322       = InitializationKind::CreateCopy(Element->getLocStart(), SourceLocation());
323     InitializationSequence Seq(S, Entity, Kind, &Element, 1);
324     if (!Seq.Failed())
325       return Seq.Perform(S, Entity, Kind, MultiExprArg(S, &Element, 1));
326   }
327 
328   Expr *OrigElement = Element;
329 
330   // Perform lvalue-to-rvalue conversion.
331   Result = S.DefaultLvalueConversion(Element);
332   if (Result.isInvalid())
333     return ExprError();
334   Element = Result.get();
335 
336   // Make sure that we have an Objective-C pointer type or block.
337   if (!Element->getType()->isObjCObjectPointerType() &&
338       !Element->getType()->isBlockPointerType()) {
339     bool Recovered = false;
340 
341     // If this is potentially an Objective-C numeric literal, add the '@'.
342     if (isa<IntegerLiteral>(OrigElement) ||
343         isa<CharacterLiteral>(OrigElement) ||
344         isa<FloatingLiteral>(OrigElement) ||
345         isa<ObjCBoolLiteralExpr>(OrigElement) ||
346         isa<CXXBoolLiteralExpr>(OrigElement)) {
347       if (S.NSAPIObj->getNSNumberFactoryMethodKind(OrigElement->getType())) {
348         int Which = isa<CharacterLiteral>(OrigElement) ? 1
349                   : (isa<CXXBoolLiteralExpr>(OrigElement) ||
350                      isa<ObjCBoolLiteralExpr>(OrigElement)) ? 2
351                   : 3;
352 
353         S.Diag(OrigElement->getLocStart(), diag::err_box_literal_collection)
354           << Which << OrigElement->getSourceRange()
355           << FixItHint::CreateInsertion(OrigElement->getLocStart(), "@");
356 
357         Result = S.BuildObjCNumericLiteral(OrigElement->getLocStart(),
358                                            OrigElement);
359         if (Result.isInvalid())
360           return ExprError();
361 
362         Element = Result.get();
363         Recovered = true;
364       }
365     }
366     // If this is potentially an Objective-C string literal, add the '@'.
367     else if (StringLiteral *String = dyn_cast<StringLiteral>(OrigElement)) {
368       if (String->isAscii()) {
369         S.Diag(OrigElement->getLocStart(), diag::err_box_literal_collection)
370           << 0 << OrigElement->getSourceRange()
371           << FixItHint::CreateInsertion(OrigElement->getLocStart(), "@");
372 
373         Result = S.BuildObjCStringLiteral(OrigElement->getLocStart(), String);
374         if (Result.isInvalid())
375           return ExprError();
376 
377         Element = Result.get();
378         Recovered = true;
379       }
380     }
381 
382     if (!Recovered) {
383       S.Diag(Element->getLocStart(), diag::err_invalid_collection_element)
384         << Element->getType();
385       return ExprError();
386     }
387   }
388 
389   // Make sure that the element has the type that the container factory
390   // function expects.
391   return S.PerformCopyInitialization(
392            InitializedEntity::InitializeParameter(S.Context, T,
393                                                   /*Consumed=*/false),
394            Element->getLocStart(), Element);
395 }
396 
BuildObjCBoxedExpr(SourceRange SR,Expr * ValueExpr)397 ExprResult Sema::BuildObjCBoxedExpr(SourceRange SR, Expr *ValueExpr) {
398   if (ValueExpr->isTypeDependent()) {
399     ObjCBoxedExpr *BoxedExpr =
400       new (Context) ObjCBoxedExpr(ValueExpr, Context.DependentTy, NULL, SR);
401     return Owned(BoxedExpr);
402   }
403   ObjCMethodDecl *BoxingMethod = NULL;
404   QualType BoxedType;
405   // Convert the expression to an RValue, so we can check for pointer types...
406   ExprResult RValue = DefaultFunctionArrayLvalueConversion(ValueExpr);
407   if (RValue.isInvalid()) {
408     return ExprError();
409   }
410   ValueExpr = RValue.get();
411   QualType ValueType(ValueExpr->getType().getCanonicalType());
412   if (const PointerType *PT = ValueType->getAs<PointerType>()) {
413     QualType PointeeType = PT->getPointeeType();
414     if (Context.hasSameUnqualifiedType(PointeeType, Context.CharTy)) {
415 
416       if (!NSStringDecl) {
417         IdentifierInfo *NSStringId =
418           NSAPIObj->getNSClassId(NSAPI::ClassId_NSString);
419         NamedDecl *Decl = LookupSingleName(TUScope, NSStringId,
420                                            SR.getBegin(), LookupOrdinaryName);
421         NSStringDecl = dyn_cast_or_null<ObjCInterfaceDecl>(Decl);
422         if (!NSStringDecl) {
423           if (getLangOpts().DebuggerObjCLiteral) {
424             // Support boxed expressions in the debugger w/o NSString declaration.
425             NSStringDecl = ObjCInterfaceDecl::Create(Context,
426                                                      Context.getTranslationUnitDecl(),
427                                                      SourceLocation(), NSStringId,
428                                                      0, SourceLocation());
429           } else {
430             Diag(SR.getBegin(), diag::err_undeclared_nsstring);
431             return ExprError();
432           }
433         } else if (!NSStringDecl->hasDefinition()) {
434           Diag(SR.getBegin(), diag::err_undeclared_nsstring);
435           return ExprError();
436         }
437         assert(NSStringDecl && "NSStringDecl should not be NULL");
438         NSStringPointer =
439           Context.getObjCObjectPointerType(Context.getObjCInterfaceType(NSStringDecl));
440       }
441 
442       if (!StringWithUTF8StringMethod) {
443         IdentifierInfo *II = &Context.Idents.get("stringWithUTF8String");
444         Selector stringWithUTF8String = Context.Selectors.getUnarySelector(II);
445 
446         // Look for the appropriate method within NSString.
447         StringWithUTF8StringMethod = NSStringDecl->lookupClassMethod(stringWithUTF8String);
448         if (!StringWithUTF8StringMethod && getLangOpts().DebuggerObjCLiteral) {
449           // Debugger needs to work even if NSString hasn't been defined.
450           TypeSourceInfo *ResultTInfo = 0;
451           ObjCMethodDecl *M =
452             ObjCMethodDecl::Create(Context, SourceLocation(), SourceLocation(),
453                                    stringWithUTF8String, NSStringPointer,
454                                    ResultTInfo, NSStringDecl,
455                                    /*isInstance=*/false, /*isVariadic=*/false,
456                                    /*isSynthesized=*/false,
457                                    /*isImplicitlyDeclared=*/true,
458                                    /*isDefined=*/false,
459                                    ObjCMethodDecl::Required,
460                                    /*HasRelatedResultType=*/false);
461           ParmVarDecl *value =
462             ParmVarDecl::Create(Context, M,
463                                 SourceLocation(), SourceLocation(),
464                                 &Context.Idents.get("value"),
465                                 Context.getPointerType(Context.CharTy.withConst()),
466                                 /*TInfo=*/0,
467                                 SC_None, SC_None, 0);
468           M->setMethodParams(Context, value, ArrayRef<SourceLocation>());
469           StringWithUTF8StringMethod = M;
470         }
471         assert(StringWithUTF8StringMethod &&
472                "StringWithUTF8StringMethod should not be NULL");
473       }
474 
475       BoxingMethod = StringWithUTF8StringMethod;
476       BoxedType = NSStringPointer;
477     }
478   } else if (isa<BuiltinType>(ValueType)) {
479     // The other types we support are numeric, char and BOOL/bool. We could also
480     // provide limited support for structure types, such as NSRange, NSRect, and
481     // NSSize. See NSValue (NSValueGeometryExtensions) in <Foundation/NSGeometry.h>
482     // for more details.
483 
484     // Check for a top-level character literal.
485     if (const CharacterLiteral *Char =
486         dyn_cast<CharacterLiteral>(ValueExpr->IgnoreParens())) {
487       // In C, character literals have type 'int'. That's not the type we want
488       // to use to determine the Objective-c literal kind.
489       switch (Char->getKind()) {
490       case CharacterLiteral::Ascii:
491         ValueType = Context.CharTy;
492         break;
493 
494       case CharacterLiteral::Wide:
495         ValueType = Context.getWCharType();
496         break;
497 
498       case CharacterLiteral::UTF16:
499         ValueType = Context.Char16Ty;
500         break;
501 
502       case CharacterLiteral::UTF32:
503         ValueType = Context.Char32Ty;
504         break;
505       }
506     }
507 
508     // FIXME:  Do I need to do anything special with BoolTy expressions?
509 
510     // Look for the appropriate method within NSNumber.
511     BoxingMethod = getNSNumberFactoryMethod(*this, SR.getBegin(), ValueType);
512     BoxedType = NSNumberPointer;
513   }
514 
515   if (!BoxingMethod) {
516     Diag(SR.getBegin(), diag::err_objc_illegal_boxed_expression_type)
517       << ValueType << ValueExpr->getSourceRange();
518     return ExprError();
519   }
520 
521   // Convert the expression to the type that the parameter requires.
522   QualType ArgType = BoxingMethod->param_begin()[0]->getType();
523   ExprResult ConvertedValueExpr = PerformImplicitConversion(ValueExpr, ArgType,
524                                                             AA_Sending);
525   if (ConvertedValueExpr.isInvalid())
526     return ExprError();
527   ValueExpr = ConvertedValueExpr.get();
528 
529   ObjCBoxedExpr *BoxedExpr =
530     new (Context) ObjCBoxedExpr(ValueExpr, BoxedType,
531                                       BoxingMethod, SR);
532   return MaybeBindToTemporary(BoxedExpr);
533 }
534 
BuildObjCSubscriptExpression(SourceLocation RB,Expr * BaseExpr,Expr * IndexExpr,ObjCMethodDecl * getterMethod,ObjCMethodDecl * setterMethod)535 ExprResult Sema::BuildObjCSubscriptExpression(SourceLocation RB, Expr *BaseExpr,
536                                         Expr *IndexExpr,
537                                         ObjCMethodDecl *getterMethod,
538                                         ObjCMethodDecl *setterMethod) {
539   // Feature support is for modern abi.
540   if (!LangOpts.ObjCNonFragileABI)
541     return ExprError();
542   // If the expression is type-dependent, there's nothing for us to do.
543   assert ((!BaseExpr->isTypeDependent() && !IndexExpr->isTypeDependent()) &&
544           "base or index cannot have dependent type here");
545   ExprResult Result = CheckPlaceholderExpr(IndexExpr);
546   if (Result.isInvalid())
547     return ExprError();
548   IndexExpr = Result.get();
549 
550   // Perform lvalue-to-rvalue conversion.
551   Result = DefaultLvalueConversion(BaseExpr);
552   if (Result.isInvalid())
553     return ExprError();
554   BaseExpr = Result.get();
555   return Owned(ObjCSubscriptRefExpr::Create(Context,
556                                             BaseExpr,
557                                             IndexExpr,
558                                             Context.PseudoObjectTy,
559                                             getterMethod,
560                                             setterMethod, RB));
561 
562 }
563 
BuildObjCArrayLiteral(SourceRange SR,MultiExprArg Elements)564 ExprResult Sema::BuildObjCArrayLiteral(SourceRange SR, MultiExprArg Elements) {
565   // Look up the NSArray class, if we haven't done so already.
566   if (!NSArrayDecl) {
567     NamedDecl *IF = LookupSingleName(TUScope,
568                                  NSAPIObj->getNSClassId(NSAPI::ClassId_NSArray),
569                                  SR.getBegin(),
570                                  LookupOrdinaryName);
571     NSArrayDecl = dyn_cast_or_null<ObjCInterfaceDecl>(IF);
572     if (!NSArrayDecl && getLangOpts().DebuggerObjCLiteral)
573       NSArrayDecl =  ObjCInterfaceDecl::Create (Context,
574                             Context.getTranslationUnitDecl(),
575                             SourceLocation(),
576                             NSAPIObj->getNSClassId(NSAPI::ClassId_NSArray),
577                             0, SourceLocation());
578 
579     if (!NSArrayDecl) {
580       Diag(SR.getBegin(), diag::err_undeclared_nsarray);
581       return ExprError();
582     }
583   }
584 
585   // Find the arrayWithObjects:count: method, if we haven't done so already.
586   QualType IdT = Context.getObjCIdType();
587   if (!ArrayWithObjectsMethod) {
588     Selector
589       Sel = NSAPIObj->getNSArraySelector(NSAPI::NSArr_arrayWithObjectsCount);
590     ArrayWithObjectsMethod = NSArrayDecl->lookupClassMethod(Sel);
591     if (!ArrayWithObjectsMethod && getLangOpts().DebuggerObjCLiteral) {
592       TypeSourceInfo *ResultTInfo = 0;
593       ArrayWithObjectsMethod =
594                          ObjCMethodDecl::Create(Context,
595                            SourceLocation(), SourceLocation(), Sel,
596                            IdT,
597                            ResultTInfo,
598                            Context.getTranslationUnitDecl(),
599                            false /*Instance*/, false/*isVariadic*/,
600                            /*isSynthesized=*/false,
601                            /*isImplicitlyDeclared=*/true, /*isDefined=*/false,
602                            ObjCMethodDecl::Required,
603                            false);
604       SmallVector<ParmVarDecl *, 2> Params;
605       ParmVarDecl *objects = ParmVarDecl::Create(Context, ArrayWithObjectsMethod,
606                                                 SourceLocation(), SourceLocation(),
607                                                 &Context.Idents.get("objects"),
608                                                 Context.getPointerType(IdT),
609                                                 /*TInfo=*/0,
610                                                 SC_None,
611                                                 SC_None,
612                                                 0);
613       Params.push_back(objects);
614       ParmVarDecl *cnt = ParmVarDecl::Create(Context, ArrayWithObjectsMethod,
615                                                 SourceLocation(), SourceLocation(),
616                                                 &Context.Idents.get("cnt"),
617                                                 Context.UnsignedLongTy,
618                                                 /*TInfo=*/0,
619                                                 SC_None,
620                                                 SC_None,
621                                                 0);
622       Params.push_back(cnt);
623       ArrayWithObjectsMethod->setMethodParams(Context, Params,
624                                               ArrayRef<SourceLocation>());
625 
626 
627     }
628 
629     if (!ArrayWithObjectsMethod) {
630       Diag(SR.getBegin(), diag::err_undeclared_arraywithobjects) << Sel;
631       return ExprError();
632     }
633   }
634 
635   // Make sure the return type is reasonable.
636   if (!ArrayWithObjectsMethod->getResultType()->isObjCObjectPointerType()) {
637     Diag(SR.getBegin(), diag::err_objc_literal_method_sig)
638       << ArrayWithObjectsMethod->getSelector();
639     Diag(ArrayWithObjectsMethod->getLocation(),
640          diag::note_objc_literal_method_return)
641       << ArrayWithObjectsMethod->getResultType();
642     return ExprError();
643   }
644 
645   // Dig out the type that all elements should be converted to.
646   QualType T = ArrayWithObjectsMethod->param_begin()[0]->getType();
647   const PointerType *PtrT = T->getAs<PointerType>();
648   if (!PtrT ||
649       !Context.hasSameUnqualifiedType(PtrT->getPointeeType(), IdT)) {
650     Diag(SR.getBegin(), diag::err_objc_literal_method_sig)
651       << ArrayWithObjectsMethod->getSelector();
652     Diag(ArrayWithObjectsMethod->param_begin()[0]->getLocation(),
653          diag::note_objc_literal_method_param)
654       << 0 << T
655       << Context.getPointerType(IdT.withConst());
656     return ExprError();
657   }
658   T = PtrT->getPointeeType();
659 
660   // Check that the 'count' parameter is integral.
661   if (!ArrayWithObjectsMethod->param_begin()[1]->getType()->isIntegerType()) {
662     Diag(SR.getBegin(), diag::err_objc_literal_method_sig)
663       << ArrayWithObjectsMethod->getSelector();
664     Diag(ArrayWithObjectsMethod->param_begin()[1]->getLocation(),
665          diag::note_objc_literal_method_param)
666       << 1
667       << ArrayWithObjectsMethod->param_begin()[1]->getType()
668       << "integral";
669     return ExprError();
670   }
671 
672   // Check that each of the elements provided is valid in a collection literal,
673   // performing conversions as necessary.
674   Expr **ElementsBuffer = Elements.get();
675   for (unsigned I = 0, N = Elements.size(); I != N; ++I) {
676     ExprResult Converted = CheckObjCCollectionLiteralElement(*this,
677                                                              ElementsBuffer[I],
678                                                              T);
679     if (Converted.isInvalid())
680       return ExprError();
681 
682     ElementsBuffer[I] = Converted.get();
683   }
684 
685   QualType Ty
686     = Context.getObjCObjectPointerType(
687                                     Context.getObjCInterfaceType(NSArrayDecl));
688 
689   return MaybeBindToTemporary(
690            ObjCArrayLiteral::Create(Context,
691                                     llvm::makeArrayRef(Elements.get(),
692                                                        Elements.size()),
693                                     Ty, ArrayWithObjectsMethod, SR));
694 }
695 
BuildObjCDictionaryLiteral(SourceRange SR,ObjCDictionaryElement * Elements,unsigned NumElements)696 ExprResult Sema::BuildObjCDictionaryLiteral(SourceRange SR,
697                                             ObjCDictionaryElement *Elements,
698                                             unsigned NumElements) {
699   // Look up the NSDictionary class, if we haven't done so already.
700   if (!NSDictionaryDecl) {
701     NamedDecl *IF = LookupSingleName(TUScope,
702                             NSAPIObj->getNSClassId(NSAPI::ClassId_NSDictionary),
703                             SR.getBegin(), LookupOrdinaryName);
704     NSDictionaryDecl = dyn_cast_or_null<ObjCInterfaceDecl>(IF);
705     if (!NSDictionaryDecl && getLangOpts().DebuggerObjCLiteral)
706       NSDictionaryDecl =  ObjCInterfaceDecl::Create (Context,
707                             Context.getTranslationUnitDecl(),
708                             SourceLocation(),
709                             NSAPIObj->getNSClassId(NSAPI::ClassId_NSDictionary),
710                             0, SourceLocation());
711 
712     if (!NSDictionaryDecl) {
713       Diag(SR.getBegin(), diag::err_undeclared_nsdictionary);
714       return ExprError();
715     }
716   }
717 
718   // Find the dictionaryWithObjects:forKeys:count: method, if we haven't done
719   // so already.
720   QualType IdT = Context.getObjCIdType();
721   if (!DictionaryWithObjectsMethod) {
722     Selector Sel = NSAPIObj->getNSDictionarySelector(
723                                     NSAPI::NSDict_dictionaryWithObjectsForKeysCount);
724     DictionaryWithObjectsMethod = NSDictionaryDecl->lookupClassMethod(Sel);
725     if (!DictionaryWithObjectsMethod && getLangOpts().DebuggerObjCLiteral) {
726       DictionaryWithObjectsMethod =
727                          ObjCMethodDecl::Create(Context,
728                            SourceLocation(), SourceLocation(), Sel,
729                            IdT,
730                            0 /*TypeSourceInfo */,
731                            Context.getTranslationUnitDecl(),
732                            false /*Instance*/, false/*isVariadic*/,
733                            /*isSynthesized=*/false,
734                            /*isImplicitlyDeclared=*/true, /*isDefined=*/false,
735                            ObjCMethodDecl::Required,
736                            false);
737       SmallVector<ParmVarDecl *, 3> Params;
738       ParmVarDecl *objects = ParmVarDecl::Create(Context, DictionaryWithObjectsMethod,
739                                                 SourceLocation(), SourceLocation(),
740                                                 &Context.Idents.get("objects"),
741                                                 Context.getPointerType(IdT),
742                                                 /*TInfo=*/0,
743                                                 SC_None,
744                                                 SC_None,
745                                                 0);
746       Params.push_back(objects);
747       ParmVarDecl *keys = ParmVarDecl::Create(Context, DictionaryWithObjectsMethod,
748                                                 SourceLocation(), SourceLocation(),
749                                                 &Context.Idents.get("keys"),
750                                                 Context.getPointerType(IdT),
751                                                 /*TInfo=*/0,
752                                                 SC_None,
753                                                 SC_None,
754                                                 0);
755       Params.push_back(keys);
756       ParmVarDecl *cnt = ParmVarDecl::Create(Context, DictionaryWithObjectsMethod,
757                                                 SourceLocation(), SourceLocation(),
758                                                 &Context.Idents.get("cnt"),
759                                                 Context.UnsignedLongTy,
760                                                 /*TInfo=*/0,
761                                                 SC_None,
762                                                 SC_None,
763                                                 0);
764       Params.push_back(cnt);
765       DictionaryWithObjectsMethod->setMethodParams(Context, Params,
766                                                    ArrayRef<SourceLocation>());
767     }
768 
769     if (!DictionaryWithObjectsMethod) {
770       Diag(SR.getBegin(), diag::err_undeclared_dictwithobjects) << Sel;
771       return ExprError();
772     }
773   }
774 
775   // Make sure the return type is reasonable.
776   if (!DictionaryWithObjectsMethod->getResultType()->isObjCObjectPointerType()){
777     Diag(SR.getBegin(), diag::err_objc_literal_method_sig)
778     << DictionaryWithObjectsMethod->getSelector();
779     Diag(DictionaryWithObjectsMethod->getLocation(),
780          diag::note_objc_literal_method_return)
781     << DictionaryWithObjectsMethod->getResultType();
782     return ExprError();
783   }
784 
785   // Dig out the type that all values should be converted to.
786   QualType ValueT =  DictionaryWithObjectsMethod->param_begin()[0]->getType();
787   const PointerType *PtrValue = ValueT->getAs<PointerType>();
788   if (!PtrValue ||
789       !Context.hasSameUnqualifiedType(PtrValue->getPointeeType(), IdT)) {
790     Diag(SR.getBegin(), diag::err_objc_literal_method_sig)
791       << DictionaryWithObjectsMethod->getSelector();
792     Diag(DictionaryWithObjectsMethod->param_begin()[0]->getLocation(),
793          diag::note_objc_literal_method_param)
794       << 0 << ValueT
795       << Context.getPointerType(IdT.withConst());
796     return ExprError();
797   }
798   ValueT = PtrValue->getPointeeType();
799 
800   // Dig out the type that all keys should be converted to.
801   QualType KeyT = DictionaryWithObjectsMethod->param_begin()[1]->getType();
802   const PointerType *PtrKey = KeyT->getAs<PointerType>();
803   if (!PtrKey ||
804       !Context.hasSameUnqualifiedType(PtrKey->getPointeeType(),
805                                       IdT)) {
806     bool err = true;
807     if (PtrKey) {
808       if (QIDNSCopying.isNull()) {
809         // key argument of selector is id<NSCopying>?
810         if (ObjCProtocolDecl *NSCopyingPDecl =
811             LookupProtocol(&Context.Idents.get("NSCopying"), SR.getBegin())) {
812           ObjCProtocolDecl *PQ[] = {NSCopyingPDecl};
813           QIDNSCopying =
814             Context.getObjCObjectType(Context.ObjCBuiltinIdTy,
815                                       (ObjCProtocolDecl**) PQ,1);
816           QIDNSCopying = Context.getObjCObjectPointerType(QIDNSCopying);
817         }
818       }
819       if (!QIDNSCopying.isNull())
820         err = !Context.hasSameUnqualifiedType(PtrKey->getPointeeType(),
821                                               QIDNSCopying);
822     }
823 
824     if (err) {
825       Diag(SR.getBegin(), diag::err_objc_literal_method_sig)
826         << DictionaryWithObjectsMethod->getSelector();
827       Diag(DictionaryWithObjectsMethod->param_begin()[1]->getLocation(),
828            diag::note_objc_literal_method_param)
829         << 1 << KeyT
830         << Context.getPointerType(IdT.withConst());
831       return ExprError();
832     }
833   }
834   KeyT = PtrKey->getPointeeType();
835 
836   // Check that the 'count' parameter is integral.
837   if (!DictionaryWithObjectsMethod->param_begin()[2]->getType()
838                                                             ->isIntegerType()) {
839     Diag(SR.getBegin(), diag::err_objc_literal_method_sig)
840       << DictionaryWithObjectsMethod->getSelector();
841     Diag(DictionaryWithObjectsMethod->param_begin()[2]->getLocation(),
842          diag::note_objc_literal_method_param)
843       << 2
844       << DictionaryWithObjectsMethod->param_begin()[2]->getType()
845       << "integral";
846     return ExprError();
847   }
848 
849   // Check that each of the keys and values provided is valid in a collection
850   // literal, performing conversions as necessary.
851   bool HasPackExpansions = false;
852   for (unsigned I = 0, N = NumElements; I != N; ++I) {
853     // Check the key.
854     ExprResult Key = CheckObjCCollectionLiteralElement(*this, Elements[I].Key,
855                                                        KeyT);
856     if (Key.isInvalid())
857       return ExprError();
858 
859     // Check the value.
860     ExprResult Value
861       = CheckObjCCollectionLiteralElement(*this, Elements[I].Value, ValueT);
862     if (Value.isInvalid())
863       return ExprError();
864 
865     Elements[I].Key = Key.get();
866     Elements[I].Value = Value.get();
867 
868     if (Elements[I].EllipsisLoc.isInvalid())
869       continue;
870 
871     if (!Elements[I].Key->containsUnexpandedParameterPack() &&
872         !Elements[I].Value->containsUnexpandedParameterPack()) {
873       Diag(Elements[I].EllipsisLoc,
874            diag::err_pack_expansion_without_parameter_packs)
875         << SourceRange(Elements[I].Key->getLocStart(),
876                        Elements[I].Value->getLocEnd());
877       return ExprError();
878     }
879 
880     HasPackExpansions = true;
881   }
882 
883 
884   QualType Ty
885     = Context.getObjCObjectPointerType(
886                                 Context.getObjCInterfaceType(NSDictionaryDecl));
887   return MaybeBindToTemporary(
888            ObjCDictionaryLiteral::Create(Context,
889                                          llvm::makeArrayRef(Elements,
890                                                             NumElements),
891                                          HasPackExpansions,
892                                          Ty,
893                                          DictionaryWithObjectsMethod, SR));
894 }
895 
BuildObjCEncodeExpression(SourceLocation AtLoc,TypeSourceInfo * EncodedTypeInfo,SourceLocation RParenLoc)896 ExprResult Sema::BuildObjCEncodeExpression(SourceLocation AtLoc,
897                                       TypeSourceInfo *EncodedTypeInfo,
898                                       SourceLocation RParenLoc) {
899   QualType EncodedType = EncodedTypeInfo->getType();
900   QualType StrTy;
901   if (EncodedType->isDependentType())
902     StrTy = Context.DependentTy;
903   else {
904     if (!EncodedType->getAsArrayTypeUnsafe() && //// Incomplete array is handled.
905         !EncodedType->isVoidType()) // void is handled too.
906       if (RequireCompleteType(AtLoc, EncodedType,
907                          PDiag(diag::err_incomplete_type_objc_at_encode)
908                              << EncodedTypeInfo->getTypeLoc().getSourceRange()))
909         return ExprError();
910 
911     std::string Str;
912     Context.getObjCEncodingForType(EncodedType, Str);
913 
914     // The type of @encode is the same as the type of the corresponding string,
915     // which is an array type.
916     StrTy = Context.CharTy;
917     // A C++ string literal has a const-qualified element type (C++ 2.13.4p1).
918     if (getLangOpts().CPlusPlus || getLangOpts().ConstStrings)
919       StrTy.addConst();
920     StrTy = Context.getConstantArrayType(StrTy, llvm::APInt(32, Str.size()+1),
921                                          ArrayType::Normal, 0);
922   }
923 
924   return new (Context) ObjCEncodeExpr(StrTy, EncodedTypeInfo, AtLoc, RParenLoc);
925 }
926 
ParseObjCEncodeExpression(SourceLocation AtLoc,SourceLocation EncodeLoc,SourceLocation LParenLoc,ParsedType ty,SourceLocation RParenLoc)927 ExprResult Sema::ParseObjCEncodeExpression(SourceLocation AtLoc,
928                                            SourceLocation EncodeLoc,
929                                            SourceLocation LParenLoc,
930                                            ParsedType ty,
931                                            SourceLocation RParenLoc) {
932   // FIXME: Preserve type source info ?
933   TypeSourceInfo *TInfo;
934   QualType EncodedType = GetTypeFromParser(ty, &TInfo);
935   if (!TInfo)
936     TInfo = Context.getTrivialTypeSourceInfo(EncodedType,
937                                              PP.getLocForEndOfToken(LParenLoc));
938 
939   return BuildObjCEncodeExpression(AtLoc, TInfo, RParenLoc);
940 }
941 
ParseObjCSelectorExpression(Selector Sel,SourceLocation AtLoc,SourceLocation SelLoc,SourceLocation LParenLoc,SourceLocation RParenLoc)942 ExprResult Sema::ParseObjCSelectorExpression(Selector Sel,
943                                              SourceLocation AtLoc,
944                                              SourceLocation SelLoc,
945                                              SourceLocation LParenLoc,
946                                              SourceLocation RParenLoc) {
947   ObjCMethodDecl *Method = LookupInstanceMethodInGlobalPool(Sel,
948                              SourceRange(LParenLoc, RParenLoc), false, false);
949   if (!Method)
950     Method = LookupFactoryMethodInGlobalPool(Sel,
951                                           SourceRange(LParenLoc, RParenLoc));
952   if (!Method)
953     Diag(SelLoc, diag::warn_undeclared_selector) << Sel;
954 
955   if (!Method ||
956       Method->getImplementationControl() != ObjCMethodDecl::Optional) {
957     llvm::DenseMap<Selector, SourceLocation>::iterator Pos
958       = ReferencedSelectors.find(Sel);
959     if (Pos == ReferencedSelectors.end())
960       ReferencedSelectors.insert(std::make_pair(Sel, SelLoc));
961   }
962 
963   // In ARC, forbid the user from using @selector for
964   // retain/release/autorelease/dealloc/retainCount.
965   if (getLangOpts().ObjCAutoRefCount) {
966     switch (Sel.getMethodFamily()) {
967     case OMF_retain:
968     case OMF_release:
969     case OMF_autorelease:
970     case OMF_retainCount:
971     case OMF_dealloc:
972       Diag(AtLoc, diag::err_arc_illegal_selector) <<
973         Sel << SourceRange(LParenLoc, RParenLoc);
974       break;
975 
976     case OMF_None:
977     case OMF_alloc:
978     case OMF_copy:
979     case OMF_finalize:
980     case OMF_init:
981     case OMF_mutableCopy:
982     case OMF_new:
983     case OMF_self:
984     case OMF_performSelector:
985       break;
986     }
987   }
988   QualType Ty = Context.getObjCSelType();
989   return new (Context) ObjCSelectorExpr(Ty, Sel, AtLoc, RParenLoc);
990 }
991 
ParseObjCProtocolExpression(IdentifierInfo * ProtocolId,SourceLocation AtLoc,SourceLocation ProtoLoc,SourceLocation LParenLoc,SourceLocation RParenLoc)992 ExprResult Sema::ParseObjCProtocolExpression(IdentifierInfo *ProtocolId,
993                                              SourceLocation AtLoc,
994                                              SourceLocation ProtoLoc,
995                                              SourceLocation LParenLoc,
996                                              SourceLocation RParenLoc) {
997   ObjCProtocolDecl* PDecl = LookupProtocol(ProtocolId, ProtoLoc);
998   if (!PDecl) {
999     Diag(ProtoLoc, diag::err_undeclared_protocol) << ProtocolId;
1000     return true;
1001   }
1002 
1003   QualType Ty = Context.getObjCProtoType();
1004   if (Ty.isNull())
1005     return true;
1006   Ty = Context.getObjCObjectPointerType(Ty);
1007   return new (Context) ObjCProtocolExpr(Ty, PDecl, AtLoc, RParenLoc);
1008 }
1009 
1010 /// Try to capture an implicit reference to 'self'.
tryCaptureObjCSelf(SourceLocation Loc)1011 ObjCMethodDecl *Sema::tryCaptureObjCSelf(SourceLocation Loc) {
1012   DeclContext *DC = getFunctionLevelDeclContext();
1013 
1014   // If we're not in an ObjC method, error out.  Note that, unlike the
1015   // C++ case, we don't require an instance method --- class methods
1016   // still have a 'self', and we really do still need to capture it!
1017   ObjCMethodDecl *method = dyn_cast<ObjCMethodDecl>(DC);
1018   if (!method)
1019     return 0;
1020 
1021   tryCaptureVariable(method->getSelfDecl(), Loc);
1022 
1023   return method;
1024 }
1025 
stripObjCInstanceType(ASTContext & Context,QualType T)1026 static QualType stripObjCInstanceType(ASTContext &Context, QualType T) {
1027   if (T == Context.getObjCInstanceType())
1028     return Context.getObjCIdType();
1029 
1030   return T;
1031 }
1032 
getMessageSendResultType(QualType ReceiverType,ObjCMethodDecl * Method,bool isClassMessage,bool isSuperMessage)1033 QualType Sema::getMessageSendResultType(QualType ReceiverType,
1034                                         ObjCMethodDecl *Method,
1035                                     bool isClassMessage, bool isSuperMessage) {
1036   assert(Method && "Must have a method");
1037   if (!Method->hasRelatedResultType())
1038     return Method->getSendResultType();
1039 
1040   // If a method has a related return type:
1041   //   - if the method found is an instance method, but the message send
1042   //     was a class message send, T is the declared return type of the method
1043   //     found
1044   if (Method->isInstanceMethod() && isClassMessage)
1045     return stripObjCInstanceType(Context, Method->getSendResultType());
1046 
1047   //   - if the receiver is super, T is a pointer to the class of the
1048   //     enclosing method definition
1049   if (isSuperMessage) {
1050     if (ObjCMethodDecl *CurMethod = getCurMethodDecl())
1051       if (ObjCInterfaceDecl *Class = CurMethod->getClassInterface())
1052         return Context.getObjCObjectPointerType(
1053                                         Context.getObjCInterfaceType(Class));
1054   }
1055 
1056   //   - if the receiver is the name of a class U, T is a pointer to U
1057   if (ReceiverType->getAs<ObjCInterfaceType>() ||
1058       ReceiverType->isObjCQualifiedInterfaceType())
1059     return Context.getObjCObjectPointerType(ReceiverType);
1060   //   - if the receiver is of type Class or qualified Class type,
1061   //     T is the declared return type of the method.
1062   if (ReceiverType->isObjCClassType() ||
1063       ReceiverType->isObjCQualifiedClassType())
1064     return stripObjCInstanceType(Context, Method->getSendResultType());
1065 
1066   //   - if the receiver is id, qualified id, Class, or qualified Class, T
1067   //     is the receiver type, otherwise
1068   //   - T is the type of the receiver expression.
1069   return ReceiverType;
1070 }
1071 
EmitRelatedResultTypeNote(const Expr * E)1072 void Sema::EmitRelatedResultTypeNote(const Expr *E) {
1073   E = E->IgnoreParenImpCasts();
1074   const ObjCMessageExpr *MsgSend = dyn_cast<ObjCMessageExpr>(E);
1075   if (!MsgSend)
1076     return;
1077 
1078   const ObjCMethodDecl *Method = MsgSend->getMethodDecl();
1079   if (!Method)
1080     return;
1081 
1082   if (!Method->hasRelatedResultType())
1083     return;
1084 
1085   if (Context.hasSameUnqualifiedType(Method->getResultType()
1086                                                         .getNonReferenceType(),
1087                                      MsgSend->getType()))
1088     return;
1089 
1090   if (!Context.hasSameUnqualifiedType(Method->getResultType(),
1091                                       Context.getObjCInstanceType()))
1092     return;
1093 
1094   Diag(Method->getLocation(), diag::note_related_result_type_inferred)
1095     << Method->isInstanceMethod() << Method->getSelector()
1096     << MsgSend->getType();
1097 }
1098 
CheckMessageArgumentTypes(QualType ReceiverType,Expr ** Args,unsigned NumArgs,Selector Sel,ObjCMethodDecl * Method,bool isClassMessage,bool isSuperMessage,SourceLocation lbrac,SourceLocation rbrac,QualType & ReturnType,ExprValueKind & VK)1099 bool Sema::CheckMessageArgumentTypes(QualType ReceiverType,
1100                                      Expr **Args, unsigned NumArgs,
1101                                      Selector Sel, ObjCMethodDecl *Method,
1102                                      bool isClassMessage, bool isSuperMessage,
1103                                      SourceLocation lbrac, SourceLocation rbrac,
1104                                      QualType &ReturnType, ExprValueKind &VK) {
1105   if (!Method) {
1106     // Apply default argument promotion as for (C99 6.5.2.2p6).
1107     for (unsigned i = 0; i != NumArgs; i++) {
1108       if (Args[i]->isTypeDependent())
1109         continue;
1110 
1111       ExprResult Result = DefaultArgumentPromotion(Args[i]);
1112       if (Result.isInvalid())
1113         return true;
1114       Args[i] = Result.take();
1115     }
1116 
1117     unsigned DiagID;
1118     if (getLangOpts().ObjCAutoRefCount)
1119       DiagID = diag::err_arc_method_not_found;
1120     else
1121       DiagID = isClassMessage ? diag::warn_class_method_not_found
1122                               : diag::warn_inst_method_not_found;
1123     if (!getLangOpts().DebuggerSupport)
1124       Diag(lbrac, DiagID)
1125         << Sel << isClassMessage << SourceRange(lbrac, rbrac);
1126 
1127     // In debuggers, we want to use __unknown_anytype for these
1128     // results so that clients can cast them.
1129     if (getLangOpts().DebuggerSupport) {
1130       ReturnType = Context.UnknownAnyTy;
1131     } else {
1132       ReturnType = Context.getObjCIdType();
1133     }
1134     VK = VK_RValue;
1135     return false;
1136   }
1137 
1138   ReturnType = getMessageSendResultType(ReceiverType, Method, isClassMessage,
1139                                         isSuperMessage);
1140   VK = Expr::getValueKindForType(Method->getResultType());
1141 
1142   unsigned NumNamedArgs = Sel.getNumArgs();
1143   // Method might have more arguments than selector indicates. This is due
1144   // to addition of c-style arguments in method.
1145   if (Method->param_size() > Sel.getNumArgs())
1146     NumNamedArgs = Method->param_size();
1147   // FIXME. This need be cleaned up.
1148   if (NumArgs < NumNamedArgs) {
1149     Diag(lbrac, diag::err_typecheck_call_too_few_args)
1150       << 2 << NumNamedArgs << NumArgs;
1151     return false;
1152   }
1153 
1154   bool IsError = false;
1155   for (unsigned i = 0; i < NumNamedArgs; i++) {
1156     // We can't do any type-checking on a type-dependent argument.
1157     if (Args[i]->isTypeDependent())
1158       continue;
1159 
1160     Expr *argExpr = Args[i];
1161 
1162     ParmVarDecl *param = Method->param_begin()[i];
1163     assert(argExpr && "CheckMessageArgumentTypes(): missing expression");
1164 
1165     // Strip the unbridged-cast placeholder expression off unless it's
1166     // a consumed argument.
1167     if (argExpr->hasPlaceholderType(BuiltinType::ARCUnbridgedCast) &&
1168         !param->hasAttr<CFConsumedAttr>())
1169       argExpr = stripARCUnbridgedCast(argExpr);
1170 
1171     if (RequireCompleteType(argExpr->getSourceRange().getBegin(),
1172                             param->getType(),
1173                             PDiag(diag::err_call_incomplete_argument)
1174                               << argExpr->getSourceRange()))
1175       return true;
1176 
1177     InitializedEntity Entity = InitializedEntity::InitializeParameter(Context,
1178                                                                       param);
1179     ExprResult ArgE = PerformCopyInitialization(Entity, lbrac, Owned(argExpr));
1180     if (ArgE.isInvalid())
1181       IsError = true;
1182     else
1183       Args[i] = ArgE.takeAs<Expr>();
1184   }
1185 
1186   // Promote additional arguments to variadic methods.
1187   if (Method->isVariadic()) {
1188     for (unsigned i = NumNamedArgs; i < NumArgs; ++i) {
1189       if (Args[i]->isTypeDependent())
1190         continue;
1191 
1192       ExprResult Arg = DefaultVariadicArgumentPromotion(Args[i], VariadicMethod, 0);
1193       IsError |= Arg.isInvalid();
1194       Args[i] = Arg.take();
1195     }
1196   } else {
1197     // Check for extra arguments to non-variadic methods.
1198     if (NumArgs != NumNamedArgs) {
1199       Diag(Args[NumNamedArgs]->getLocStart(),
1200            diag::err_typecheck_call_too_many_args)
1201         << 2 /*method*/ << NumNamedArgs << NumArgs
1202         << Method->getSourceRange()
1203         << SourceRange(Args[NumNamedArgs]->getLocStart(),
1204                        Args[NumArgs-1]->getLocEnd());
1205     }
1206   }
1207 
1208   DiagnoseSentinelCalls(Method, lbrac, Args, NumArgs);
1209 
1210   // Do additional checkings on method.
1211   IsError |= CheckObjCMethodCall(Method, lbrac, Args, NumArgs);
1212 
1213   return IsError;
1214 }
1215 
isSelfExpr(Expr * receiver)1216 bool Sema::isSelfExpr(Expr *receiver) {
1217   // 'self' is objc 'self' in an objc method only.
1218   ObjCMethodDecl *method =
1219     dyn_cast<ObjCMethodDecl>(CurContext->getNonClosureAncestor());
1220   if (!method) return false;
1221 
1222   receiver = receiver->IgnoreParenLValueCasts();
1223   if (DeclRefExpr *DRE = dyn_cast<DeclRefExpr>(receiver))
1224     if (DRE->getDecl() == method->getSelfDecl())
1225       return true;
1226   return false;
1227 }
1228 
1229 // Helper method for ActOnClassMethod/ActOnInstanceMethod.
1230 // Will search "local" class/category implementations for a method decl.
1231 // If failed, then we search in class's root for an instance method.
1232 // Returns 0 if no method is found.
LookupPrivateClassMethod(Selector Sel,ObjCInterfaceDecl * ClassDecl)1233 ObjCMethodDecl *Sema::LookupPrivateClassMethod(Selector Sel,
1234                                           ObjCInterfaceDecl *ClassDecl) {
1235   ObjCMethodDecl *Method = 0;
1236   // lookup in class and all superclasses
1237   while (ClassDecl && !Method) {
1238     if (ObjCImplementationDecl *ImpDecl = ClassDecl->getImplementation())
1239       Method = ImpDecl->getClassMethod(Sel);
1240 
1241     // Look through local category implementations associated with the class.
1242     if (!Method)
1243       Method = ClassDecl->getCategoryClassMethod(Sel);
1244 
1245     // Before we give up, check if the selector is an instance method.
1246     // But only in the root. This matches gcc's behaviour and what the
1247     // runtime expects.
1248     if (!Method && !ClassDecl->getSuperClass()) {
1249       Method = ClassDecl->lookupInstanceMethod(Sel);
1250       // Look through local category implementations associated
1251       // with the root class.
1252       if (!Method)
1253         Method = LookupPrivateInstanceMethod(Sel, ClassDecl);
1254     }
1255 
1256     ClassDecl = ClassDecl->getSuperClass();
1257   }
1258   return Method;
1259 }
1260 
LookupPrivateInstanceMethod(Selector Sel,ObjCInterfaceDecl * ClassDecl)1261 ObjCMethodDecl *Sema::LookupPrivateInstanceMethod(Selector Sel,
1262                                               ObjCInterfaceDecl *ClassDecl) {
1263   if (!ClassDecl->hasDefinition())
1264     return 0;
1265 
1266   ObjCMethodDecl *Method = 0;
1267   while (ClassDecl && !Method) {
1268     // If we have implementations in scope, check "private" methods.
1269     if (ObjCImplementationDecl *ImpDecl = ClassDecl->getImplementation())
1270       Method = ImpDecl->getInstanceMethod(Sel);
1271 
1272     // Look through local category implementations associated with the class.
1273     if (!Method)
1274       Method = ClassDecl->getCategoryInstanceMethod(Sel);
1275     ClassDecl = ClassDecl->getSuperClass();
1276   }
1277   return Method;
1278 }
1279 
1280 /// LookupMethodInType - Look up a method in an ObjCObjectType.
LookupMethodInObjectType(Selector sel,QualType type,bool isInstance)1281 ObjCMethodDecl *Sema::LookupMethodInObjectType(Selector sel, QualType type,
1282                                                bool isInstance) {
1283   const ObjCObjectType *objType = type->castAs<ObjCObjectType>();
1284   if (ObjCInterfaceDecl *iface = objType->getInterface()) {
1285     // Look it up in the main interface (and categories, etc.)
1286     if (ObjCMethodDecl *method = iface->lookupMethod(sel, isInstance))
1287       return method;
1288 
1289     // Okay, look for "private" methods declared in any
1290     // @implementations we've seen.
1291     if (isInstance) {
1292       if (ObjCMethodDecl *method = LookupPrivateInstanceMethod(sel, iface))
1293         return method;
1294     } else {
1295       if (ObjCMethodDecl *method = LookupPrivateClassMethod(sel, iface))
1296         return method;
1297     }
1298   }
1299 
1300   // Check qualifiers.
1301   for (ObjCObjectType::qual_iterator
1302          i = objType->qual_begin(), e = objType->qual_end(); i != e; ++i)
1303     if (ObjCMethodDecl *method = (*i)->lookupMethod(sel, isInstance))
1304       return method;
1305 
1306   return 0;
1307 }
1308 
1309 /// LookupMethodInQualifiedType - Lookups up a method in protocol qualifier
1310 /// list of a qualified objective pointer type.
LookupMethodInQualifiedType(Selector Sel,const ObjCObjectPointerType * OPT,bool Instance)1311 ObjCMethodDecl *Sema::LookupMethodInQualifiedType(Selector Sel,
1312                                               const ObjCObjectPointerType *OPT,
1313                                               bool Instance)
1314 {
1315   ObjCMethodDecl *MD = 0;
1316   for (ObjCObjectPointerType::qual_iterator I = OPT->qual_begin(),
1317        E = OPT->qual_end(); I != E; ++I) {
1318     ObjCProtocolDecl *PROTO = (*I);
1319     if ((MD = PROTO->lookupMethod(Sel, Instance))) {
1320       return MD;
1321     }
1322   }
1323   return 0;
1324 }
1325 
1326 /// HandleExprPropertyRefExpr - Handle foo.bar where foo is a pointer to an
1327 /// objective C interface.  This is a property reference expression.
1328 ExprResult Sema::
HandleExprPropertyRefExpr(const ObjCObjectPointerType * OPT,Expr * BaseExpr,SourceLocation OpLoc,DeclarationName MemberName,SourceLocation MemberLoc,SourceLocation SuperLoc,QualType SuperType,bool Super)1329 HandleExprPropertyRefExpr(const ObjCObjectPointerType *OPT,
1330                           Expr *BaseExpr, SourceLocation OpLoc,
1331                           DeclarationName MemberName,
1332                           SourceLocation MemberLoc,
1333                           SourceLocation SuperLoc, QualType SuperType,
1334                           bool Super) {
1335   const ObjCInterfaceType *IFaceT = OPT->getInterfaceType();
1336   ObjCInterfaceDecl *IFace = IFaceT->getDecl();
1337 
1338   if (MemberName.getNameKind() != DeclarationName::Identifier) {
1339     Diag(MemberLoc, diag::err_invalid_property_name)
1340       << MemberName << QualType(OPT, 0);
1341     return ExprError();
1342   }
1343 
1344   IdentifierInfo *Member = MemberName.getAsIdentifierInfo();
1345   SourceRange BaseRange = Super? SourceRange(SuperLoc)
1346                                : BaseExpr->getSourceRange();
1347   if (RequireCompleteType(MemberLoc, OPT->getPointeeType(),
1348                           PDiag(diag::err_property_not_found_forward_class)
1349                             << MemberName << BaseRange))
1350     return ExprError();
1351 
1352   // Search for a declared property first.
1353   if (ObjCPropertyDecl *PD = IFace->FindPropertyDeclaration(Member)) {
1354     // Check whether we can reference this property.
1355     if (DiagnoseUseOfDecl(PD, MemberLoc))
1356       return ExprError();
1357 
1358     if (Super)
1359       return Owned(new (Context) ObjCPropertyRefExpr(PD, Context.PseudoObjectTy,
1360                                                      VK_LValue, OK_ObjCProperty,
1361                                                      MemberLoc,
1362                                                      SuperLoc, SuperType));
1363     else
1364       return Owned(new (Context) ObjCPropertyRefExpr(PD, Context.PseudoObjectTy,
1365                                                      VK_LValue, OK_ObjCProperty,
1366                                                      MemberLoc, BaseExpr));
1367   }
1368   // Check protocols on qualified interfaces.
1369   for (ObjCObjectPointerType::qual_iterator I = OPT->qual_begin(),
1370        E = OPT->qual_end(); I != E; ++I)
1371     if (ObjCPropertyDecl *PD = (*I)->FindPropertyDeclaration(Member)) {
1372       // Check whether we can reference this property.
1373       if (DiagnoseUseOfDecl(PD, MemberLoc))
1374         return ExprError();
1375 
1376       if (Super)
1377         return Owned(new (Context) ObjCPropertyRefExpr(PD,
1378                                                        Context.PseudoObjectTy,
1379                                                        VK_LValue,
1380                                                        OK_ObjCProperty,
1381                                                        MemberLoc,
1382                                                        SuperLoc, SuperType));
1383       else
1384         return Owned(new (Context) ObjCPropertyRefExpr(PD,
1385                                                        Context.PseudoObjectTy,
1386                                                        VK_LValue,
1387                                                        OK_ObjCProperty,
1388                                                        MemberLoc,
1389                                                        BaseExpr));
1390     }
1391   // If that failed, look for an "implicit" property by seeing if the nullary
1392   // selector is implemented.
1393 
1394   // FIXME: The logic for looking up nullary and unary selectors should be
1395   // shared with the code in ActOnInstanceMessage.
1396 
1397   Selector Sel = PP.getSelectorTable().getNullarySelector(Member);
1398   ObjCMethodDecl *Getter = IFace->lookupInstanceMethod(Sel);
1399 
1400   // May be founf in property's qualified list.
1401   if (!Getter)
1402     Getter = LookupMethodInQualifiedType(Sel, OPT, true);
1403 
1404   // If this reference is in an @implementation, check for 'private' methods.
1405   if (!Getter)
1406     Getter = IFace->lookupPrivateMethod(Sel);
1407 
1408   // Look through local category implementations associated with the class.
1409   if (!Getter)
1410     Getter = IFace->getCategoryInstanceMethod(Sel);
1411   if (Getter) {
1412     // Check if we can reference this property.
1413     if (DiagnoseUseOfDecl(Getter, MemberLoc))
1414       return ExprError();
1415   }
1416   // If we found a getter then this may be a valid dot-reference, we
1417   // will look for the matching setter, in case it is needed.
1418   Selector SetterSel =
1419     SelectorTable::constructSetterName(PP.getIdentifierTable(),
1420                                        PP.getSelectorTable(), Member);
1421   ObjCMethodDecl *Setter = IFace->lookupInstanceMethod(SetterSel);
1422 
1423   // May be founf in property's qualified list.
1424   if (!Setter)
1425     Setter = LookupMethodInQualifiedType(SetterSel, OPT, true);
1426 
1427   if (!Setter) {
1428     // If this reference is in an @implementation, also check for 'private'
1429     // methods.
1430     Setter = IFace->lookupPrivateMethod(SetterSel);
1431   }
1432   // Look through local category implementations associated with the class.
1433   if (!Setter)
1434     Setter = IFace->getCategoryInstanceMethod(SetterSel);
1435 
1436   if (Setter && DiagnoseUseOfDecl(Setter, MemberLoc))
1437     return ExprError();
1438 
1439   if (Getter || Setter) {
1440     if (Super)
1441       return Owned(new (Context) ObjCPropertyRefExpr(Getter, Setter,
1442                                                      Context.PseudoObjectTy,
1443                                                      VK_LValue, OK_ObjCProperty,
1444                                                      MemberLoc,
1445                                                      SuperLoc, SuperType));
1446     else
1447       return Owned(new (Context) ObjCPropertyRefExpr(Getter, Setter,
1448                                                      Context.PseudoObjectTy,
1449                                                      VK_LValue, OK_ObjCProperty,
1450                                                      MemberLoc, BaseExpr));
1451 
1452   }
1453 
1454   // Attempt to correct for typos in property names.
1455   DeclFilterCCC<ObjCPropertyDecl> Validator;
1456   if (TypoCorrection Corrected = CorrectTypo(
1457       DeclarationNameInfo(MemberName, MemberLoc), LookupOrdinaryName, NULL,
1458       NULL, Validator, IFace, false, OPT)) {
1459     ObjCPropertyDecl *Property =
1460         Corrected.getCorrectionDeclAs<ObjCPropertyDecl>();
1461     DeclarationName TypoResult = Corrected.getCorrection();
1462     Diag(MemberLoc, diag::err_property_not_found_suggest)
1463       << MemberName << QualType(OPT, 0) << TypoResult
1464       << FixItHint::CreateReplacement(MemberLoc, TypoResult.getAsString());
1465     Diag(Property->getLocation(), diag::note_previous_decl)
1466       << Property->getDeclName();
1467     return HandleExprPropertyRefExpr(OPT, BaseExpr, OpLoc,
1468                                      TypoResult, MemberLoc,
1469                                      SuperLoc, SuperType, Super);
1470   }
1471   ObjCInterfaceDecl *ClassDeclared;
1472   if (ObjCIvarDecl *Ivar =
1473       IFace->lookupInstanceVariable(Member, ClassDeclared)) {
1474     QualType T = Ivar->getType();
1475     if (const ObjCObjectPointerType * OBJPT =
1476         T->getAsObjCInterfacePointerType()) {
1477       if (RequireCompleteType(MemberLoc, OBJPT->getPointeeType(),
1478                               PDiag(diag::err_property_not_as_forward_class)
1479                                 << MemberName << BaseExpr->getSourceRange()))
1480         return ExprError();
1481     }
1482     Diag(MemberLoc,
1483          diag::err_ivar_access_using_property_syntax_suggest)
1484     << MemberName << QualType(OPT, 0) << Ivar->getDeclName()
1485     << FixItHint::CreateReplacement(OpLoc, "->");
1486     return ExprError();
1487   }
1488 
1489   Diag(MemberLoc, diag::err_property_not_found)
1490     << MemberName << QualType(OPT, 0);
1491   if (Setter)
1492     Diag(Setter->getLocation(), diag::note_getter_unavailable)
1493           << MemberName << BaseExpr->getSourceRange();
1494   return ExprError();
1495 }
1496 
1497 
1498 
1499 ExprResult Sema::
ActOnClassPropertyRefExpr(IdentifierInfo & receiverName,IdentifierInfo & propertyName,SourceLocation receiverNameLoc,SourceLocation propertyNameLoc)1500 ActOnClassPropertyRefExpr(IdentifierInfo &receiverName,
1501                           IdentifierInfo &propertyName,
1502                           SourceLocation receiverNameLoc,
1503                           SourceLocation propertyNameLoc) {
1504 
1505   IdentifierInfo *receiverNamePtr = &receiverName;
1506   ObjCInterfaceDecl *IFace = getObjCInterfaceDecl(receiverNamePtr,
1507                                                   receiverNameLoc);
1508 
1509   bool IsSuper = false;
1510   if (IFace == 0) {
1511     // If the "receiver" is 'super' in a method, handle it as an expression-like
1512     // property reference.
1513     if (receiverNamePtr->isStr("super")) {
1514       IsSuper = true;
1515 
1516       if (ObjCMethodDecl *CurMethod = tryCaptureObjCSelf(receiverNameLoc)) {
1517         if (CurMethod->isInstanceMethod()) {
1518           QualType T =
1519             Context.getObjCInterfaceType(CurMethod->getClassInterface());
1520           T = Context.getObjCObjectPointerType(T);
1521 
1522           return HandleExprPropertyRefExpr(T->getAsObjCInterfacePointerType(),
1523                                            /*BaseExpr*/0,
1524                                            SourceLocation()/*OpLoc*/,
1525                                            &propertyName,
1526                                            propertyNameLoc,
1527                                            receiverNameLoc, T, true);
1528         }
1529 
1530         // Otherwise, if this is a class method, try dispatching to our
1531         // superclass.
1532         IFace = CurMethod->getClassInterface()->getSuperClass();
1533       }
1534     }
1535 
1536     if (IFace == 0) {
1537       Diag(receiverNameLoc, diag::err_expected_ident_or_lparen);
1538       return ExprError();
1539     }
1540   }
1541 
1542   // Search for a declared property first.
1543   Selector Sel = PP.getSelectorTable().getNullarySelector(&propertyName);
1544   ObjCMethodDecl *Getter = IFace->lookupClassMethod(Sel);
1545 
1546   // If this reference is in an @implementation, check for 'private' methods.
1547   if (!Getter)
1548     if (ObjCMethodDecl *CurMeth = getCurMethodDecl())
1549       if (ObjCInterfaceDecl *ClassDecl = CurMeth->getClassInterface())
1550         if (ObjCImplementationDecl *ImpDecl = ClassDecl->getImplementation())
1551           Getter = ImpDecl->getClassMethod(Sel);
1552 
1553   if (Getter) {
1554     // FIXME: refactor/share with ActOnMemberReference().
1555     // Check if we can reference this property.
1556     if (DiagnoseUseOfDecl(Getter, propertyNameLoc))
1557       return ExprError();
1558   }
1559 
1560   // Look for the matching setter, in case it is needed.
1561   Selector SetterSel =
1562     SelectorTable::constructSetterName(PP.getIdentifierTable(),
1563                                        PP.getSelectorTable(), &propertyName);
1564 
1565   ObjCMethodDecl *Setter = IFace->lookupClassMethod(SetterSel);
1566   if (!Setter) {
1567     // If this reference is in an @implementation, also check for 'private'
1568     // methods.
1569     if (ObjCMethodDecl *CurMeth = getCurMethodDecl())
1570       if (ObjCInterfaceDecl *ClassDecl = CurMeth->getClassInterface())
1571         if (ObjCImplementationDecl *ImpDecl = ClassDecl->getImplementation())
1572           Setter = ImpDecl->getClassMethod(SetterSel);
1573   }
1574   // Look through local category implementations associated with the class.
1575   if (!Setter)
1576     Setter = IFace->getCategoryClassMethod(SetterSel);
1577 
1578   if (Setter && DiagnoseUseOfDecl(Setter, propertyNameLoc))
1579     return ExprError();
1580 
1581   if (Getter || Setter) {
1582     if (IsSuper)
1583     return Owned(new (Context) ObjCPropertyRefExpr(Getter, Setter,
1584                                                    Context.PseudoObjectTy,
1585                                                    VK_LValue, OK_ObjCProperty,
1586                                                    propertyNameLoc,
1587                                                    receiverNameLoc,
1588                                           Context.getObjCInterfaceType(IFace)));
1589 
1590     return Owned(new (Context) ObjCPropertyRefExpr(Getter, Setter,
1591                                                    Context.PseudoObjectTy,
1592                                                    VK_LValue, OK_ObjCProperty,
1593                                                    propertyNameLoc,
1594                                                    receiverNameLoc, IFace));
1595   }
1596   return ExprError(Diag(propertyNameLoc, diag::err_property_not_found)
1597                      << &propertyName << Context.getObjCInterfaceType(IFace));
1598 }
1599 
1600 namespace {
1601 
1602 class ObjCInterfaceOrSuperCCC : public CorrectionCandidateCallback {
1603  public:
ObjCInterfaceOrSuperCCC(ObjCMethodDecl * Method)1604   ObjCInterfaceOrSuperCCC(ObjCMethodDecl *Method) {
1605     // Determine whether "super" is acceptable in the current context.
1606     if (Method && Method->getClassInterface())
1607       WantObjCSuper = Method->getClassInterface()->getSuperClass();
1608   }
1609 
ValidateCandidate(const TypoCorrection & candidate)1610   virtual bool ValidateCandidate(const TypoCorrection &candidate) {
1611     return candidate.getCorrectionDeclAs<ObjCInterfaceDecl>() ||
1612         candidate.isKeyword("super");
1613   }
1614 };
1615 
1616 }
1617 
getObjCMessageKind(Scope * S,IdentifierInfo * Name,SourceLocation NameLoc,bool IsSuper,bool HasTrailingDot,ParsedType & ReceiverType)1618 Sema::ObjCMessageKind Sema::getObjCMessageKind(Scope *S,
1619                                                IdentifierInfo *Name,
1620                                                SourceLocation NameLoc,
1621                                                bool IsSuper,
1622                                                bool HasTrailingDot,
1623                                                ParsedType &ReceiverType) {
1624   ReceiverType = ParsedType();
1625 
1626   // If the identifier is "super" and there is no trailing dot, we're
1627   // messaging super. If the identifier is "super" and there is a
1628   // trailing dot, it's an instance message.
1629   if (IsSuper && S->isInObjcMethodScope())
1630     return HasTrailingDot? ObjCInstanceMessage : ObjCSuperMessage;
1631 
1632   LookupResult Result(*this, Name, NameLoc, LookupOrdinaryName);
1633   LookupName(Result, S);
1634 
1635   switch (Result.getResultKind()) {
1636   case LookupResult::NotFound:
1637     // Normal name lookup didn't find anything. If we're in an
1638     // Objective-C method, look for ivars. If we find one, we're done!
1639     // FIXME: This is a hack. Ivar lookup should be part of normal
1640     // lookup.
1641     if (ObjCMethodDecl *Method = getCurMethodDecl()) {
1642       if (!Method->getClassInterface()) {
1643         // Fall back: let the parser try to parse it as an instance message.
1644         return ObjCInstanceMessage;
1645       }
1646 
1647       ObjCInterfaceDecl *ClassDeclared;
1648       if (Method->getClassInterface()->lookupInstanceVariable(Name,
1649                                                               ClassDeclared))
1650         return ObjCInstanceMessage;
1651     }
1652 
1653     // Break out; we'll perform typo correction below.
1654     break;
1655 
1656   case LookupResult::NotFoundInCurrentInstantiation:
1657   case LookupResult::FoundOverloaded:
1658   case LookupResult::FoundUnresolvedValue:
1659   case LookupResult::Ambiguous:
1660     Result.suppressDiagnostics();
1661     return ObjCInstanceMessage;
1662 
1663   case LookupResult::Found: {
1664     // If the identifier is a class or not, and there is a trailing dot,
1665     // it's an instance message.
1666     if (HasTrailingDot)
1667       return ObjCInstanceMessage;
1668     // We found something. If it's a type, then we have a class
1669     // message. Otherwise, it's an instance message.
1670     NamedDecl *ND = Result.getFoundDecl();
1671     QualType T;
1672     if (ObjCInterfaceDecl *Class = dyn_cast<ObjCInterfaceDecl>(ND))
1673       T = Context.getObjCInterfaceType(Class);
1674     else if (TypeDecl *Type = dyn_cast<TypeDecl>(ND))
1675       T = Context.getTypeDeclType(Type);
1676     else
1677       return ObjCInstanceMessage;
1678 
1679     //  We have a class message, and T is the type we're
1680     //  messaging. Build source-location information for it.
1681     TypeSourceInfo *TSInfo = Context.getTrivialTypeSourceInfo(T, NameLoc);
1682     ReceiverType = CreateParsedType(T, TSInfo);
1683     return ObjCClassMessage;
1684   }
1685   }
1686 
1687   ObjCInterfaceOrSuperCCC Validator(getCurMethodDecl());
1688   if (TypoCorrection Corrected = CorrectTypo(Result.getLookupNameInfo(),
1689                                              Result.getLookupKind(), S, NULL,
1690                                              Validator)) {
1691     if (Corrected.isKeyword()) {
1692       // If we've found the keyword "super" (the only keyword that would be
1693       // returned by CorrectTypo), this is a send to super.
1694       Diag(NameLoc, diag::err_unknown_receiver_suggest)
1695         << Name << Corrected.getCorrection()
1696         << FixItHint::CreateReplacement(SourceRange(NameLoc), "super");
1697       return ObjCSuperMessage;
1698     } else if (ObjCInterfaceDecl *Class =
1699                Corrected.getCorrectionDeclAs<ObjCInterfaceDecl>()) {
1700       // If we found a declaration, correct when it refers to an Objective-C
1701       // class.
1702       Diag(NameLoc, diag::err_unknown_receiver_suggest)
1703         << Name << Corrected.getCorrection()
1704         << FixItHint::CreateReplacement(SourceRange(NameLoc),
1705                                         Class->getNameAsString());
1706       Diag(Class->getLocation(), diag::note_previous_decl)
1707         << Corrected.getCorrection();
1708 
1709       QualType T = Context.getObjCInterfaceType(Class);
1710       TypeSourceInfo *TSInfo = Context.getTrivialTypeSourceInfo(T, NameLoc);
1711       ReceiverType = CreateParsedType(T, TSInfo);
1712       return ObjCClassMessage;
1713     }
1714   }
1715 
1716   // Fall back: let the parser try to parse it as an instance message.
1717   return ObjCInstanceMessage;
1718 }
1719 
ActOnSuperMessage(Scope * S,SourceLocation SuperLoc,Selector Sel,SourceLocation LBracLoc,ArrayRef<SourceLocation> SelectorLocs,SourceLocation RBracLoc,MultiExprArg Args)1720 ExprResult Sema::ActOnSuperMessage(Scope *S,
1721                                    SourceLocation SuperLoc,
1722                                    Selector Sel,
1723                                    SourceLocation LBracLoc,
1724                                    ArrayRef<SourceLocation> SelectorLocs,
1725                                    SourceLocation RBracLoc,
1726                                    MultiExprArg Args) {
1727   // Determine whether we are inside a method or not.
1728   ObjCMethodDecl *Method = tryCaptureObjCSelf(SuperLoc);
1729   if (!Method) {
1730     Diag(SuperLoc, diag::err_invalid_receiver_to_message_super);
1731     return ExprError();
1732   }
1733 
1734   ObjCInterfaceDecl *Class = Method->getClassInterface();
1735   if (!Class) {
1736     Diag(SuperLoc, diag::error_no_super_class_message)
1737       << Method->getDeclName();
1738     return ExprError();
1739   }
1740 
1741   ObjCInterfaceDecl *Super = Class->getSuperClass();
1742   if (!Super) {
1743     // The current class does not have a superclass.
1744     Diag(SuperLoc, diag::error_root_class_cannot_use_super)
1745       << Class->getIdentifier();
1746     return ExprError();
1747   }
1748 
1749   // We are in a method whose class has a superclass, so 'super'
1750   // is acting as a keyword.
1751   if (Method->isInstanceMethod()) {
1752     if (Sel.getMethodFamily() == OMF_dealloc)
1753       ObjCShouldCallSuperDealloc = false;
1754     if (Sel.getMethodFamily() == OMF_finalize)
1755       ObjCShouldCallSuperFinalize = false;
1756 
1757     // Since we are in an instance method, this is an instance
1758     // message to the superclass instance.
1759     QualType SuperTy = Context.getObjCInterfaceType(Super);
1760     SuperTy = Context.getObjCObjectPointerType(SuperTy);
1761     return BuildInstanceMessage(0, SuperTy, SuperLoc,
1762                                 Sel, /*Method=*/0,
1763                                 LBracLoc, SelectorLocs, RBracLoc, move(Args));
1764   }
1765 
1766   // Since we are in a class method, this is a class message to
1767   // the superclass.
1768   return BuildClassMessage(/*ReceiverTypeInfo=*/0,
1769                            Context.getObjCInterfaceType(Super),
1770                            SuperLoc, Sel, /*Method=*/0,
1771                            LBracLoc, SelectorLocs, RBracLoc, move(Args));
1772 }
1773 
1774 
BuildClassMessageImplicit(QualType ReceiverType,bool isSuperReceiver,SourceLocation Loc,Selector Sel,ObjCMethodDecl * Method,MultiExprArg Args)1775 ExprResult Sema::BuildClassMessageImplicit(QualType ReceiverType,
1776                                            bool isSuperReceiver,
1777                                            SourceLocation Loc,
1778                                            Selector Sel,
1779                                            ObjCMethodDecl *Method,
1780                                            MultiExprArg Args) {
1781   TypeSourceInfo *receiverTypeInfo = 0;
1782   if (!ReceiverType.isNull())
1783     receiverTypeInfo = Context.getTrivialTypeSourceInfo(ReceiverType);
1784 
1785   return BuildClassMessage(receiverTypeInfo, ReceiverType,
1786                           /*SuperLoc=*/isSuperReceiver ? Loc : SourceLocation(),
1787                            Sel, Method, Loc, Loc, Loc, Args,
1788                            /*isImplicit=*/true);
1789 
1790 }
1791 
applyCocoaAPICheck(Sema & S,const ObjCMessageExpr * Msg,unsigned DiagID,bool (* refactor)(const ObjCMessageExpr *,const NSAPI &,edit::Commit &))1792 static void applyCocoaAPICheck(Sema &S, const ObjCMessageExpr *Msg,
1793                                unsigned DiagID,
1794                                bool (*refactor)(const ObjCMessageExpr *,
1795                                               const NSAPI &, edit::Commit &)) {
1796   SourceLocation MsgLoc = Msg->getExprLoc();
1797   if (S.Diags.getDiagnosticLevel(DiagID, MsgLoc) == DiagnosticsEngine::Ignored)
1798     return;
1799 
1800   SourceManager &SM = S.SourceMgr;
1801   edit::Commit ECommit(SM, S.LangOpts);
1802   if (refactor(Msg,*S.NSAPIObj, ECommit)) {
1803     DiagnosticBuilder Builder = S.Diag(MsgLoc, DiagID)
1804                         << Msg->getSelector() << Msg->getSourceRange();
1805     // FIXME: Don't emit diagnostic at all if fixits are non-commitable.
1806     if (!ECommit.isCommitable())
1807       return;
1808     for (edit::Commit::edit_iterator
1809            I = ECommit.edit_begin(), E = ECommit.edit_end(); I != E; ++I) {
1810       const edit::Commit::Edit &Edit = *I;
1811       switch (Edit.Kind) {
1812       case edit::Commit::Act_Insert:
1813         Builder.AddFixItHint(FixItHint::CreateInsertion(Edit.OrigLoc,
1814                                                         Edit.Text,
1815                                                         Edit.BeforePrev));
1816         break;
1817       case edit::Commit::Act_InsertFromRange:
1818         Builder.AddFixItHint(
1819             FixItHint::CreateInsertionFromRange(Edit.OrigLoc,
1820                                                 Edit.getInsertFromRange(SM),
1821                                                 Edit.BeforePrev));
1822         break;
1823       case edit::Commit::Act_Remove:
1824         Builder.AddFixItHint(FixItHint::CreateRemoval(Edit.getFileRange(SM)));
1825         break;
1826       }
1827     }
1828   }
1829 }
1830 
checkCocoaAPI(Sema & S,const ObjCMessageExpr * Msg)1831 static void checkCocoaAPI(Sema &S, const ObjCMessageExpr *Msg) {
1832   applyCocoaAPICheck(S, Msg, diag::warn_objc_redundant_literal_use,
1833                      edit::rewriteObjCRedundantCallWithLiteral);
1834 }
1835 
1836 /// \brief Build an Objective-C class message expression.
1837 ///
1838 /// This routine takes care of both normal class messages and
1839 /// class messages to the superclass.
1840 ///
1841 /// \param ReceiverTypeInfo Type source information that describes the
1842 /// receiver of this message. This may be NULL, in which case we are
1843 /// sending to the superclass and \p SuperLoc must be a valid source
1844 /// location.
1845 
1846 /// \param ReceiverType The type of the object receiving the
1847 /// message. When \p ReceiverTypeInfo is non-NULL, this is the same
1848 /// type as that refers to. For a superclass send, this is the type of
1849 /// the superclass.
1850 ///
1851 /// \param SuperLoc The location of the "super" keyword in a
1852 /// superclass message.
1853 ///
1854 /// \param Sel The selector to which the message is being sent.
1855 ///
1856 /// \param Method The method that this class message is invoking, if
1857 /// already known.
1858 ///
1859 /// \param LBracLoc The location of the opening square bracket ']'.
1860 ///
1861 /// \param RBrac The location of the closing square bracket ']'.
1862 ///
1863 /// \param Args The message arguments.
BuildClassMessage(TypeSourceInfo * ReceiverTypeInfo,QualType ReceiverType,SourceLocation SuperLoc,Selector Sel,ObjCMethodDecl * Method,SourceLocation LBracLoc,ArrayRef<SourceLocation> SelectorLocs,SourceLocation RBracLoc,MultiExprArg ArgsIn,bool isImplicit)1864 ExprResult Sema::BuildClassMessage(TypeSourceInfo *ReceiverTypeInfo,
1865                                    QualType ReceiverType,
1866                                    SourceLocation SuperLoc,
1867                                    Selector Sel,
1868                                    ObjCMethodDecl *Method,
1869                                    SourceLocation LBracLoc,
1870                                    ArrayRef<SourceLocation> SelectorLocs,
1871                                    SourceLocation RBracLoc,
1872                                    MultiExprArg ArgsIn,
1873                                    bool isImplicit) {
1874   SourceLocation Loc = SuperLoc.isValid()? SuperLoc
1875     : ReceiverTypeInfo->getTypeLoc().getSourceRange().getBegin();
1876   if (LBracLoc.isInvalid()) {
1877     Diag(Loc, diag::err_missing_open_square_message_send)
1878       << FixItHint::CreateInsertion(Loc, "[");
1879     LBracLoc = Loc;
1880   }
1881 
1882   if (ReceiverType->isDependentType()) {
1883     // If the receiver type is dependent, we can't type-check anything
1884     // at this point. Build a dependent expression.
1885     unsigned NumArgs = ArgsIn.size();
1886     Expr **Args = reinterpret_cast<Expr **>(ArgsIn.release());
1887     assert(SuperLoc.isInvalid() && "Message to super with dependent type");
1888     return Owned(ObjCMessageExpr::Create(Context, ReceiverType,
1889                                          VK_RValue, LBracLoc, ReceiverTypeInfo,
1890                                          Sel, SelectorLocs, /*Method=*/0,
1891                                          makeArrayRef(Args, NumArgs),RBracLoc,
1892                                          isImplicit));
1893   }
1894 
1895   // Find the class to which we are sending this message.
1896   ObjCInterfaceDecl *Class = 0;
1897   const ObjCObjectType *ClassType = ReceiverType->getAs<ObjCObjectType>();
1898   if (!ClassType || !(Class = ClassType->getInterface())) {
1899     Diag(Loc, diag::err_invalid_receiver_class_message)
1900       << ReceiverType;
1901     return ExprError();
1902   }
1903   assert(Class && "We don't know which class we're messaging?");
1904   // objc++ diagnoses during typename annotation.
1905   if (!getLangOpts().CPlusPlus)
1906     (void)DiagnoseUseOfDecl(Class, Loc);
1907   // Find the method we are messaging.
1908   if (!Method) {
1909     SourceRange TypeRange
1910       = SuperLoc.isValid()? SourceRange(SuperLoc)
1911                           : ReceiverTypeInfo->getTypeLoc().getSourceRange();
1912     if (RequireCompleteType(Loc, Context.getObjCInterfaceType(Class),
1913                             (getLangOpts().ObjCAutoRefCount
1914                                ? PDiag(diag::err_arc_receiver_forward_class)
1915                                : PDiag(diag::warn_receiver_forward_class))
1916                                    << TypeRange)) {
1917       // A forward class used in messaging is treated as a 'Class'
1918       Method = LookupFactoryMethodInGlobalPool(Sel,
1919                                                SourceRange(LBracLoc, RBracLoc));
1920       if (Method && !getLangOpts().ObjCAutoRefCount)
1921         Diag(Method->getLocation(), diag::note_method_sent_forward_class)
1922           << Method->getDeclName();
1923     }
1924     if (!Method)
1925       Method = Class->lookupClassMethod(Sel);
1926 
1927     // If we have an implementation in scope, check "private" methods.
1928     if (!Method)
1929       Method = LookupPrivateClassMethod(Sel, Class);
1930 
1931     if (Method && DiagnoseUseOfDecl(Method, Loc))
1932       return ExprError();
1933   }
1934 
1935   // Check the argument types and determine the result type.
1936   QualType ReturnType;
1937   ExprValueKind VK = VK_RValue;
1938 
1939   unsigned NumArgs = ArgsIn.size();
1940   Expr **Args = reinterpret_cast<Expr **>(ArgsIn.release());
1941   if (CheckMessageArgumentTypes(ReceiverType, Args, NumArgs, Sel, Method, true,
1942                                 SuperLoc.isValid(), LBracLoc, RBracLoc,
1943                                 ReturnType, VK))
1944     return ExprError();
1945 
1946   if (Method && !Method->getResultType()->isVoidType() &&
1947       RequireCompleteType(LBracLoc, Method->getResultType(),
1948                           diag::err_illegal_message_expr_incomplete_type))
1949     return ExprError();
1950 
1951   // Construct the appropriate ObjCMessageExpr.
1952   ObjCMessageExpr *Result;
1953   if (SuperLoc.isValid())
1954     Result = ObjCMessageExpr::Create(Context, ReturnType, VK, LBracLoc,
1955                                      SuperLoc, /*IsInstanceSuper=*/false,
1956                                      ReceiverType, Sel, SelectorLocs,
1957                                      Method, makeArrayRef(Args, NumArgs),
1958                                      RBracLoc, isImplicit);
1959   else {
1960     Result = ObjCMessageExpr::Create(Context, ReturnType, VK, LBracLoc,
1961                                      ReceiverTypeInfo, Sel, SelectorLocs,
1962                                      Method, makeArrayRef(Args, NumArgs),
1963                                      RBracLoc, isImplicit);
1964     if (!isImplicit)
1965       checkCocoaAPI(*this, Result);
1966   }
1967   return MaybeBindToTemporary(Result);
1968 }
1969 
1970 // ActOnClassMessage - used for both unary and keyword messages.
1971 // ArgExprs is optional - if it is present, the number of expressions
1972 // is obtained from Sel.getNumArgs().
ActOnClassMessage(Scope * S,ParsedType Receiver,Selector Sel,SourceLocation LBracLoc,ArrayRef<SourceLocation> SelectorLocs,SourceLocation RBracLoc,MultiExprArg Args)1973 ExprResult Sema::ActOnClassMessage(Scope *S,
1974                                    ParsedType Receiver,
1975                                    Selector Sel,
1976                                    SourceLocation LBracLoc,
1977                                    ArrayRef<SourceLocation> SelectorLocs,
1978                                    SourceLocation RBracLoc,
1979                                    MultiExprArg Args) {
1980   TypeSourceInfo *ReceiverTypeInfo;
1981   QualType ReceiverType = GetTypeFromParser(Receiver, &ReceiverTypeInfo);
1982   if (ReceiverType.isNull())
1983     return ExprError();
1984 
1985 
1986   if (!ReceiverTypeInfo)
1987     ReceiverTypeInfo = Context.getTrivialTypeSourceInfo(ReceiverType, LBracLoc);
1988 
1989   return BuildClassMessage(ReceiverTypeInfo, ReceiverType,
1990                            /*SuperLoc=*/SourceLocation(), Sel, /*Method=*/0,
1991                            LBracLoc, SelectorLocs, RBracLoc, move(Args));
1992 }
1993 
BuildInstanceMessageImplicit(Expr * Receiver,QualType ReceiverType,SourceLocation Loc,Selector Sel,ObjCMethodDecl * Method,MultiExprArg Args)1994 ExprResult Sema::BuildInstanceMessageImplicit(Expr *Receiver,
1995                                               QualType ReceiverType,
1996                                               SourceLocation Loc,
1997                                               Selector Sel,
1998                                               ObjCMethodDecl *Method,
1999                                               MultiExprArg Args) {
2000   return BuildInstanceMessage(Receiver, ReceiverType,
2001                               /*SuperLoc=*/!Receiver ? Loc : SourceLocation(),
2002                               Sel, Method, Loc, Loc, Loc, Args,
2003                               /*isImplicit=*/true);
2004 }
2005 
2006 /// \brief Build an Objective-C instance message expression.
2007 ///
2008 /// This routine takes care of both normal instance messages and
2009 /// instance messages to the superclass instance.
2010 ///
2011 /// \param Receiver The expression that computes the object that will
2012 /// receive this message. This may be empty, in which case we are
2013 /// sending to the superclass instance and \p SuperLoc must be a valid
2014 /// source location.
2015 ///
2016 /// \param ReceiverType The (static) type of the object receiving the
2017 /// message. When a \p Receiver expression is provided, this is the
2018 /// same type as that expression. For a superclass instance send, this
2019 /// is a pointer to the type of the superclass.
2020 ///
2021 /// \param SuperLoc The location of the "super" keyword in a
2022 /// superclass instance message.
2023 ///
2024 /// \param Sel The selector to which the message is being sent.
2025 ///
2026 /// \param Method The method that this instance message is invoking, if
2027 /// already known.
2028 ///
2029 /// \param LBracLoc The location of the opening square bracket ']'.
2030 ///
2031 /// \param RBrac The location of the closing square bracket ']'.
2032 ///
2033 /// \param Args The message arguments.
BuildInstanceMessage(Expr * Receiver,QualType ReceiverType,SourceLocation SuperLoc,Selector Sel,ObjCMethodDecl * Method,SourceLocation LBracLoc,ArrayRef<SourceLocation> SelectorLocs,SourceLocation RBracLoc,MultiExprArg ArgsIn,bool isImplicit)2034 ExprResult Sema::BuildInstanceMessage(Expr *Receiver,
2035                                       QualType ReceiverType,
2036                                       SourceLocation SuperLoc,
2037                                       Selector Sel,
2038                                       ObjCMethodDecl *Method,
2039                                       SourceLocation LBracLoc,
2040                                       ArrayRef<SourceLocation> SelectorLocs,
2041                                       SourceLocation RBracLoc,
2042                                       MultiExprArg ArgsIn,
2043                                       bool isImplicit) {
2044   // The location of the receiver.
2045   SourceLocation Loc = SuperLoc.isValid()? SuperLoc : Receiver->getLocStart();
2046 
2047   if (LBracLoc.isInvalid()) {
2048     Diag(Loc, diag::err_missing_open_square_message_send)
2049       << FixItHint::CreateInsertion(Loc, "[");
2050     LBracLoc = Loc;
2051   }
2052 
2053   // If we have a receiver expression, perform appropriate promotions
2054   // and determine receiver type.
2055   if (Receiver) {
2056     if (Receiver->hasPlaceholderType()) {
2057       ExprResult Result;
2058       if (Receiver->getType() == Context.UnknownAnyTy)
2059         Result = forceUnknownAnyToType(Receiver, Context.getObjCIdType());
2060       else
2061         Result = CheckPlaceholderExpr(Receiver);
2062       if (Result.isInvalid()) return ExprError();
2063       Receiver = Result.take();
2064     }
2065 
2066     if (Receiver->isTypeDependent()) {
2067       // If the receiver is type-dependent, we can't type-check anything
2068       // at this point. Build a dependent expression.
2069       unsigned NumArgs = ArgsIn.size();
2070       Expr **Args = reinterpret_cast<Expr **>(ArgsIn.release());
2071       assert(SuperLoc.isInvalid() && "Message to super with dependent type");
2072       return Owned(ObjCMessageExpr::Create(Context, Context.DependentTy,
2073                                            VK_RValue, LBracLoc, Receiver, Sel,
2074                                            SelectorLocs, /*Method=*/0,
2075                                            makeArrayRef(Args, NumArgs),
2076                                            RBracLoc, isImplicit));
2077     }
2078 
2079     // If necessary, apply function/array conversion to the receiver.
2080     // C99 6.7.5.3p[7,8].
2081     ExprResult Result = DefaultFunctionArrayLvalueConversion(Receiver);
2082     if (Result.isInvalid())
2083       return ExprError();
2084     Receiver = Result.take();
2085     ReceiverType = Receiver->getType();
2086   }
2087 
2088   if (!Method) {
2089     // Handle messages to id.
2090     bool receiverIsId = ReceiverType->isObjCIdType();
2091     if (receiverIsId || ReceiverType->isBlockPointerType() ||
2092         (Receiver && Context.isObjCNSObjectType(Receiver->getType()))) {
2093       Method = LookupInstanceMethodInGlobalPool(Sel,
2094                                                 SourceRange(LBracLoc, RBracLoc),
2095                                                 receiverIsId);
2096       if (!Method)
2097         Method = LookupFactoryMethodInGlobalPool(Sel,
2098                                                  SourceRange(LBracLoc, RBracLoc),
2099                                                  receiverIsId);
2100     } else if (ReceiverType->isObjCClassType() ||
2101                ReceiverType->isObjCQualifiedClassType()) {
2102       // Handle messages to Class.
2103       // We allow sending a message to a qualified Class ("Class<foo>"), which
2104       // is ok as long as one of the protocols implements the selector (if not, warn).
2105       if (const ObjCObjectPointerType *QClassTy
2106             = ReceiverType->getAsObjCQualifiedClassType()) {
2107         // Search protocols for class methods.
2108         Method = LookupMethodInQualifiedType(Sel, QClassTy, false);
2109         if (!Method) {
2110           Method = LookupMethodInQualifiedType(Sel, QClassTy, true);
2111           // warn if instance method found for a Class message.
2112           if (Method) {
2113             Diag(Loc, diag::warn_instance_method_on_class_found)
2114               << Method->getSelector() << Sel;
2115             Diag(Method->getLocation(), diag::note_method_declared_at)
2116               << Method->getDeclName();
2117           }
2118         }
2119       } else {
2120         if (ObjCMethodDecl *CurMeth = getCurMethodDecl()) {
2121           if (ObjCInterfaceDecl *ClassDecl = CurMeth->getClassInterface()) {
2122             // First check the public methods in the class interface.
2123             Method = ClassDecl->lookupClassMethod(Sel);
2124 
2125             if (!Method)
2126               Method = LookupPrivateClassMethod(Sel, ClassDecl);
2127           }
2128           if (Method && DiagnoseUseOfDecl(Method, Loc))
2129             return ExprError();
2130         }
2131         if (!Method) {
2132           // If not messaging 'self', look for any factory method named 'Sel'.
2133           if (!Receiver || !isSelfExpr(Receiver)) {
2134             Method = LookupFactoryMethodInGlobalPool(Sel,
2135                                                 SourceRange(LBracLoc, RBracLoc),
2136                                                      true);
2137             if (!Method) {
2138               // If no class (factory) method was found, check if an _instance_
2139               // method of the same name exists in the root class only.
2140               Method = LookupInstanceMethodInGlobalPool(Sel,
2141                                                SourceRange(LBracLoc, RBracLoc),
2142                                                         true);
2143               if (Method)
2144                   if (const ObjCInterfaceDecl *ID =
2145                       dyn_cast<ObjCInterfaceDecl>(Method->getDeclContext())) {
2146                     if (ID->getSuperClass())
2147                       Diag(Loc, diag::warn_root_inst_method_not_found)
2148                       << Sel << SourceRange(LBracLoc, RBracLoc);
2149                   }
2150             }
2151           }
2152         }
2153       }
2154     } else {
2155       ObjCInterfaceDecl* ClassDecl = 0;
2156 
2157       // We allow sending a message to a qualified ID ("id<foo>"), which is ok as
2158       // long as one of the protocols implements the selector (if not, warn).
2159       if (const ObjCObjectPointerType *QIdTy
2160                                    = ReceiverType->getAsObjCQualifiedIdType()) {
2161         // Search protocols for instance methods.
2162         Method = LookupMethodInQualifiedType(Sel, QIdTy, true);
2163         if (!Method)
2164           Method = LookupMethodInQualifiedType(Sel, QIdTy, false);
2165       } else if (const ObjCObjectPointerType *OCIType
2166                    = ReceiverType->getAsObjCInterfacePointerType()) {
2167         // We allow sending a message to a pointer to an interface (an object).
2168         ClassDecl = OCIType->getInterfaceDecl();
2169 
2170         // Try to complete the type. Under ARC, this is a hard error from which
2171         // we don't try to recover.
2172         const ObjCInterfaceDecl *forwardClass = 0;
2173         if (RequireCompleteType(Loc, OCIType->getPointeeType(),
2174               getLangOpts().ObjCAutoRefCount
2175                 ? PDiag(diag::err_arc_receiver_forward_instance)
2176                     << (Receiver ? Receiver->getSourceRange()
2177                                  : SourceRange(SuperLoc))
2178                 : PDiag(diag::warn_receiver_forward_instance)
2179                     << (Receiver ? Receiver->getSourceRange()
2180                                  : SourceRange(SuperLoc)))) {
2181           if (getLangOpts().ObjCAutoRefCount)
2182             return ExprError();
2183 
2184           forwardClass = OCIType->getInterfaceDecl();
2185           Diag(Receiver ? Receiver->getLocStart()
2186                         : SuperLoc, diag::note_receiver_is_id);
2187           Method = 0;
2188         } else {
2189           Method = ClassDecl->lookupInstanceMethod(Sel);
2190         }
2191 
2192         if (!Method)
2193           // Search protocol qualifiers.
2194           Method = LookupMethodInQualifiedType(Sel, OCIType, true);
2195 
2196         if (!Method) {
2197           // If we have implementations in scope, check "private" methods.
2198           Method = LookupPrivateInstanceMethod(Sel, ClassDecl);
2199 
2200           if (!Method && getLangOpts().ObjCAutoRefCount) {
2201             Diag(Loc, diag::err_arc_may_not_respond)
2202               << OCIType->getPointeeType() << Sel;
2203             return ExprError();
2204           }
2205 
2206           if (!Method && (!Receiver || !isSelfExpr(Receiver))) {
2207             // If we still haven't found a method, look in the global pool. This
2208             // behavior isn't very desirable, however we need it for GCC
2209             // compatibility. FIXME: should we deviate??
2210             if (OCIType->qual_empty()) {
2211               Method = LookupInstanceMethodInGlobalPool(Sel,
2212                                                  SourceRange(LBracLoc, RBracLoc));
2213               if (Method && !forwardClass)
2214                 Diag(Loc, diag::warn_maynot_respond)
2215                   << OCIType->getInterfaceDecl()->getIdentifier() << Sel;
2216             }
2217           }
2218         }
2219         if (Method && DiagnoseUseOfDecl(Method, Loc, forwardClass))
2220           return ExprError();
2221       } else if (!getLangOpts().ObjCAutoRefCount &&
2222                  !Context.getObjCIdType().isNull() &&
2223                  (ReceiverType->isPointerType() ||
2224                   ReceiverType->isIntegerType())) {
2225         // Implicitly convert integers and pointers to 'id' but emit a warning.
2226         // But not in ARC.
2227         Diag(Loc, diag::warn_bad_receiver_type)
2228           << ReceiverType
2229           << Receiver->getSourceRange();
2230         if (ReceiverType->isPointerType())
2231           Receiver = ImpCastExprToType(Receiver, Context.getObjCIdType(),
2232                             CK_CPointerToObjCPointerCast).take();
2233         else {
2234           // TODO: specialized warning on null receivers?
2235           bool IsNull = Receiver->isNullPointerConstant(Context,
2236                                               Expr::NPC_ValueDependentIsNull);
2237           Receiver = ImpCastExprToType(Receiver, Context.getObjCIdType(),
2238                             IsNull ? CK_NullToPointer : CK_IntegralToPointer).take();
2239         }
2240         ReceiverType = Receiver->getType();
2241       } else {
2242         ExprResult ReceiverRes;
2243         if (getLangOpts().CPlusPlus)
2244           ReceiverRes = PerformContextuallyConvertToObjCPointer(Receiver);
2245         if (ReceiverRes.isUsable()) {
2246           Receiver = ReceiverRes.take();
2247           return BuildInstanceMessage(Receiver,
2248                                       ReceiverType,
2249                                       SuperLoc,
2250                                       Sel,
2251                                       Method,
2252                                       LBracLoc,
2253                                       SelectorLocs,
2254                                       RBracLoc,
2255                                       move(ArgsIn));
2256         } else {
2257           // Reject other random receiver types (e.g. structs).
2258           Diag(Loc, diag::err_bad_receiver_type)
2259             << ReceiverType << Receiver->getSourceRange();
2260           return ExprError();
2261         }
2262       }
2263     }
2264   }
2265 
2266   // Check the message arguments.
2267   unsigned NumArgs = ArgsIn.size();
2268   Expr **Args = reinterpret_cast<Expr **>(ArgsIn.release());
2269   QualType ReturnType;
2270   ExprValueKind VK = VK_RValue;
2271   bool ClassMessage = (ReceiverType->isObjCClassType() ||
2272                        ReceiverType->isObjCQualifiedClassType());
2273   if (CheckMessageArgumentTypes(ReceiverType, Args, NumArgs, Sel, Method,
2274                                 ClassMessage, SuperLoc.isValid(),
2275                                 LBracLoc, RBracLoc, ReturnType, VK))
2276     return ExprError();
2277 
2278   if (Method && !Method->getResultType()->isVoidType() &&
2279       RequireCompleteType(LBracLoc, Method->getResultType(),
2280                           diag::err_illegal_message_expr_incomplete_type))
2281     return ExprError();
2282 
2283   SourceLocation SelLoc = SelectorLocs.front();
2284 
2285   // In ARC, forbid the user from sending messages to
2286   // retain/release/autorelease/dealloc/retainCount explicitly.
2287   if (getLangOpts().ObjCAutoRefCount) {
2288     ObjCMethodFamily family =
2289       (Method ? Method->getMethodFamily() : Sel.getMethodFamily());
2290     switch (family) {
2291     case OMF_init:
2292       if (Method)
2293         checkInitMethod(Method, ReceiverType);
2294 
2295     case OMF_None:
2296     case OMF_alloc:
2297     case OMF_copy:
2298     case OMF_finalize:
2299     case OMF_mutableCopy:
2300     case OMF_new:
2301     case OMF_self:
2302       break;
2303 
2304     case OMF_dealloc:
2305     case OMF_retain:
2306     case OMF_release:
2307     case OMF_autorelease:
2308     case OMF_retainCount:
2309       Diag(Loc, diag::err_arc_illegal_explicit_message)
2310         << Sel << SelLoc;
2311       break;
2312 
2313     case OMF_performSelector:
2314       if (Method && NumArgs >= 1) {
2315         if (ObjCSelectorExpr *SelExp = dyn_cast<ObjCSelectorExpr>(Args[0])) {
2316           Selector ArgSel = SelExp->getSelector();
2317           ObjCMethodDecl *SelMethod =
2318             LookupInstanceMethodInGlobalPool(ArgSel,
2319                                              SelExp->getSourceRange());
2320           if (!SelMethod)
2321             SelMethod =
2322               LookupFactoryMethodInGlobalPool(ArgSel,
2323                                               SelExp->getSourceRange());
2324           if (SelMethod) {
2325             ObjCMethodFamily SelFamily = SelMethod->getMethodFamily();
2326             switch (SelFamily) {
2327               case OMF_alloc:
2328               case OMF_copy:
2329               case OMF_mutableCopy:
2330               case OMF_new:
2331               case OMF_self:
2332               case OMF_init:
2333                 // Issue error, unless ns_returns_not_retained.
2334                 if (!SelMethod->hasAttr<NSReturnsNotRetainedAttr>()) {
2335                   // selector names a +1 method
2336                   Diag(SelLoc,
2337                        diag::err_arc_perform_selector_retains);
2338                   Diag(SelMethod->getLocation(), diag::note_method_declared_at)
2339                     << SelMethod->getDeclName();
2340                 }
2341                 break;
2342               default:
2343                 // +0 call. OK. unless ns_returns_retained.
2344                 if (SelMethod->hasAttr<NSReturnsRetainedAttr>()) {
2345                   // selector names a +1 method
2346                   Diag(SelLoc,
2347                        diag::err_arc_perform_selector_retains);
2348                   Diag(SelMethod->getLocation(), diag::note_method_declared_at)
2349                     << SelMethod->getDeclName();
2350                 }
2351                 break;
2352             }
2353           }
2354         } else {
2355           // error (may leak).
2356           Diag(SelLoc, diag::warn_arc_perform_selector_leaks);
2357           Diag(Args[0]->getExprLoc(), diag::note_used_here);
2358         }
2359       }
2360       break;
2361     }
2362   }
2363 
2364   // Construct the appropriate ObjCMessageExpr instance.
2365   ObjCMessageExpr *Result;
2366   if (SuperLoc.isValid())
2367     Result = ObjCMessageExpr::Create(Context, ReturnType, VK, LBracLoc,
2368                                      SuperLoc,  /*IsInstanceSuper=*/true,
2369                                      ReceiverType, Sel, SelectorLocs, Method,
2370                                      makeArrayRef(Args, NumArgs), RBracLoc,
2371                                      isImplicit);
2372   else {
2373     Result = ObjCMessageExpr::Create(Context, ReturnType, VK, LBracLoc,
2374                                      Receiver, Sel, SelectorLocs, Method,
2375                                      makeArrayRef(Args, NumArgs), RBracLoc,
2376                                      isImplicit);
2377     if (!isImplicit)
2378       checkCocoaAPI(*this, Result);
2379   }
2380 
2381   if (getLangOpts().ObjCAutoRefCount) {
2382     if (Receiver &&
2383         (Receiver->IgnoreParenImpCasts()->getType().getObjCLifetime()
2384           == Qualifiers::OCL_Weak))
2385       Diag(Receiver->getLocStart(), diag::warn_receiver_is_weak);
2386 
2387     // In ARC, annotate delegate init calls.
2388     if (Result->getMethodFamily() == OMF_init &&
2389         (SuperLoc.isValid() || isSelfExpr(Receiver))) {
2390       // Only consider init calls *directly* in init implementations,
2391       // not within blocks.
2392       ObjCMethodDecl *method = dyn_cast<ObjCMethodDecl>(CurContext);
2393       if (method && method->getMethodFamily() == OMF_init) {
2394         // The implicit assignment to self means we also don't want to
2395         // consume the result.
2396         Result->setDelegateInitCall(true);
2397         return Owned(Result);
2398       }
2399     }
2400 
2401     // In ARC, check for message sends which are likely to introduce
2402     // retain cycles.
2403     checkRetainCycles(Result);
2404   }
2405 
2406   return MaybeBindToTemporary(Result);
2407 }
2408 
2409 // ActOnInstanceMessage - used for both unary and keyword messages.
2410 // ArgExprs is optional - if it is present, the number of expressions
2411 // is obtained from Sel.getNumArgs().
ActOnInstanceMessage(Scope * S,Expr * Receiver,Selector Sel,SourceLocation LBracLoc,ArrayRef<SourceLocation> SelectorLocs,SourceLocation RBracLoc,MultiExprArg Args)2412 ExprResult Sema::ActOnInstanceMessage(Scope *S,
2413                                       Expr *Receiver,
2414                                       Selector Sel,
2415                                       SourceLocation LBracLoc,
2416                                       ArrayRef<SourceLocation> SelectorLocs,
2417                                       SourceLocation RBracLoc,
2418                                       MultiExprArg Args) {
2419   if (!Receiver)
2420     return ExprError();
2421 
2422   return BuildInstanceMessage(Receiver, Receiver->getType(),
2423                               /*SuperLoc=*/SourceLocation(), Sel, /*Method=*/0,
2424                               LBracLoc, SelectorLocs, RBracLoc, move(Args));
2425 }
2426 
2427 enum ARCConversionTypeClass {
2428   /// int, void, struct A
2429   ACTC_none,
2430 
2431   /// id, void (^)()
2432   ACTC_retainable,
2433 
2434   /// id*, id***, void (^*)(),
2435   ACTC_indirectRetainable,
2436 
2437   /// void* might be a normal C type, or it might a CF type.
2438   ACTC_voidPtr,
2439 
2440   /// struct A*
2441   ACTC_coreFoundation
2442 };
isAnyRetainable(ARCConversionTypeClass ACTC)2443 static bool isAnyRetainable(ARCConversionTypeClass ACTC) {
2444   return (ACTC == ACTC_retainable ||
2445           ACTC == ACTC_coreFoundation ||
2446           ACTC == ACTC_voidPtr);
2447 }
isAnyCLike(ARCConversionTypeClass ACTC)2448 static bool isAnyCLike(ARCConversionTypeClass ACTC) {
2449   return ACTC == ACTC_none ||
2450          ACTC == ACTC_voidPtr ||
2451          ACTC == ACTC_coreFoundation;
2452 }
2453 
classifyTypeForARCConversion(QualType type)2454 static ARCConversionTypeClass classifyTypeForARCConversion(QualType type) {
2455   bool isIndirect = false;
2456 
2457   // Ignore an outermost reference type.
2458   if (const ReferenceType *ref = type->getAs<ReferenceType>()) {
2459     type = ref->getPointeeType();
2460     isIndirect = true;
2461   }
2462 
2463   // Drill through pointers and arrays recursively.
2464   while (true) {
2465     if (const PointerType *ptr = type->getAs<PointerType>()) {
2466       type = ptr->getPointeeType();
2467 
2468       // The first level of pointer may be the innermost pointer on a CF type.
2469       if (!isIndirect) {
2470         if (type->isVoidType()) return ACTC_voidPtr;
2471         if (type->isRecordType()) return ACTC_coreFoundation;
2472       }
2473     } else if (const ArrayType *array = type->getAsArrayTypeUnsafe()) {
2474       type = QualType(array->getElementType()->getBaseElementTypeUnsafe(), 0);
2475     } else {
2476       break;
2477     }
2478     isIndirect = true;
2479   }
2480 
2481   if (isIndirect) {
2482     if (type->isObjCARCBridgableType())
2483       return ACTC_indirectRetainable;
2484     return ACTC_none;
2485   }
2486 
2487   if (type->isObjCARCBridgableType())
2488     return ACTC_retainable;
2489 
2490   return ACTC_none;
2491 }
2492 
2493 namespace {
2494   /// A result from the cast checker.
2495   enum ACCResult {
2496     /// Cannot be casted.
2497     ACC_invalid,
2498 
2499     /// Can be safely retained or not retained.
2500     ACC_bottom,
2501 
2502     /// Can be casted at +0.
2503     ACC_plusZero,
2504 
2505     /// Can be casted at +1.
2506     ACC_plusOne
2507   };
merge(ACCResult left,ACCResult right)2508   ACCResult merge(ACCResult left, ACCResult right) {
2509     if (left == right) return left;
2510     if (left == ACC_bottom) return right;
2511     if (right == ACC_bottom) return left;
2512     return ACC_invalid;
2513   }
2514 
2515   /// A checker which white-lists certain expressions whose conversion
2516   /// to or from retainable type would otherwise be forbidden in ARC.
2517   class ARCCastChecker : public StmtVisitor<ARCCastChecker, ACCResult> {
2518     typedef StmtVisitor<ARCCastChecker, ACCResult> super;
2519 
2520     ASTContext &Context;
2521     ARCConversionTypeClass SourceClass;
2522     ARCConversionTypeClass TargetClass;
2523 
isCFType(QualType type)2524     static bool isCFType(QualType type) {
2525       // Someday this can use ns_bridged.  For now, it has to do this.
2526       return type->isCARCBridgableType();
2527     }
2528 
2529   public:
ARCCastChecker(ASTContext & Context,ARCConversionTypeClass source,ARCConversionTypeClass target)2530     ARCCastChecker(ASTContext &Context, ARCConversionTypeClass source,
2531                    ARCConversionTypeClass target)
2532       : Context(Context), SourceClass(source), TargetClass(target) {}
2533 
2534     using super::Visit;
Visit(Expr * e)2535     ACCResult Visit(Expr *e) {
2536       return super::Visit(e->IgnoreParens());
2537     }
2538 
VisitStmt(Stmt * s)2539     ACCResult VisitStmt(Stmt *s) {
2540       return ACC_invalid;
2541     }
2542 
2543     /// Null pointer constants can be casted however you please.
VisitExpr(Expr * e)2544     ACCResult VisitExpr(Expr *e) {
2545       if (e->isNullPointerConstant(Context, Expr::NPC_ValueDependentIsNotNull))
2546         return ACC_bottom;
2547       return ACC_invalid;
2548     }
2549 
2550     /// Objective-C string literals can be safely casted.
VisitObjCStringLiteral(ObjCStringLiteral * e)2551     ACCResult VisitObjCStringLiteral(ObjCStringLiteral *e) {
2552       // If we're casting to any retainable type, go ahead.  Global
2553       // strings are immune to retains, so this is bottom.
2554       if (isAnyRetainable(TargetClass)) return ACC_bottom;
2555 
2556       return ACC_invalid;
2557     }
2558 
2559     /// Look through certain implicit and explicit casts.
VisitCastExpr(CastExpr * e)2560     ACCResult VisitCastExpr(CastExpr *e) {
2561       switch (e->getCastKind()) {
2562         case CK_NullToPointer:
2563           return ACC_bottom;
2564 
2565         case CK_NoOp:
2566         case CK_LValueToRValue:
2567         case CK_BitCast:
2568         case CK_CPointerToObjCPointerCast:
2569         case CK_BlockPointerToObjCPointerCast:
2570         case CK_AnyPointerToBlockPointerCast:
2571           return Visit(e->getSubExpr());
2572 
2573         default:
2574           return ACC_invalid;
2575       }
2576     }
2577 
2578     /// Look through unary extension.
VisitUnaryExtension(UnaryOperator * e)2579     ACCResult VisitUnaryExtension(UnaryOperator *e) {
2580       return Visit(e->getSubExpr());
2581     }
2582 
2583     /// Ignore the LHS of a comma operator.
VisitBinComma(BinaryOperator * e)2584     ACCResult VisitBinComma(BinaryOperator *e) {
2585       return Visit(e->getRHS());
2586     }
2587 
2588     /// Conditional operators are okay if both sides are okay.
VisitConditionalOperator(ConditionalOperator * e)2589     ACCResult VisitConditionalOperator(ConditionalOperator *e) {
2590       ACCResult left = Visit(e->getTrueExpr());
2591       if (left == ACC_invalid) return ACC_invalid;
2592       return merge(left, Visit(e->getFalseExpr()));
2593     }
2594 
2595     /// Look through pseudo-objects.
VisitPseudoObjectExpr(PseudoObjectExpr * e)2596     ACCResult VisitPseudoObjectExpr(PseudoObjectExpr *e) {
2597       // If we're getting here, we should always have a result.
2598       return Visit(e->getResultExpr());
2599     }
2600 
2601     /// Statement expressions are okay if their result expression is okay.
VisitStmtExpr(StmtExpr * e)2602     ACCResult VisitStmtExpr(StmtExpr *e) {
2603       return Visit(e->getSubStmt()->body_back());
2604     }
2605 
2606     /// Some declaration references are okay.
VisitDeclRefExpr(DeclRefExpr * e)2607     ACCResult VisitDeclRefExpr(DeclRefExpr *e) {
2608       // References to global constants from system headers are okay.
2609       // These are things like 'kCFStringTransformToLatin'.  They are
2610       // can also be assumed to be immune to retains.
2611       VarDecl *var = dyn_cast<VarDecl>(e->getDecl());
2612       if (isAnyRetainable(TargetClass) &&
2613           isAnyRetainable(SourceClass) &&
2614           var &&
2615           var->getStorageClass() == SC_Extern &&
2616           var->getType().isConstQualified() &&
2617           Context.getSourceManager().isInSystemHeader(var->getLocation())) {
2618         return ACC_bottom;
2619       }
2620 
2621       // Nothing else.
2622       return ACC_invalid;
2623     }
2624 
2625     /// Some calls are okay.
VisitCallExpr(CallExpr * e)2626     ACCResult VisitCallExpr(CallExpr *e) {
2627       if (FunctionDecl *fn = e->getDirectCallee())
2628         if (ACCResult result = checkCallToFunction(fn))
2629           return result;
2630 
2631       return super::VisitCallExpr(e);
2632     }
2633 
checkCallToFunction(FunctionDecl * fn)2634     ACCResult checkCallToFunction(FunctionDecl *fn) {
2635       // Require a CF*Ref return type.
2636       if (!isCFType(fn->getResultType()))
2637         return ACC_invalid;
2638 
2639       if (!isAnyRetainable(TargetClass))
2640         return ACC_invalid;
2641 
2642       // Honor an explicit 'not retained' attribute.
2643       if (fn->hasAttr<CFReturnsNotRetainedAttr>())
2644         return ACC_plusZero;
2645 
2646       // Honor an explicit 'retained' attribute, except that for
2647       // now we're not going to permit implicit handling of +1 results,
2648       // because it's a bit frightening.
2649       if (fn->hasAttr<CFReturnsRetainedAttr>())
2650         return ACC_invalid; // ACC_plusOne if we start accepting this
2651 
2652       // Recognize this specific builtin function, which is used by CFSTR.
2653       unsigned builtinID = fn->getBuiltinID();
2654       if (builtinID == Builtin::BI__builtin___CFStringMakeConstantString)
2655         return ACC_bottom;
2656 
2657       // Otherwise, don't do anything implicit with an unaudited function.
2658       if (!fn->hasAttr<CFAuditedTransferAttr>())
2659         return ACC_invalid;
2660 
2661       // Otherwise, it's +0 unless it follows the create convention.
2662       if (ento::coreFoundation::followsCreateRule(fn))
2663         return ACC_invalid; // ACC_plusOne if we start accepting this
2664 
2665       return ACC_plusZero;
2666     }
2667 
VisitObjCMessageExpr(ObjCMessageExpr * e)2668     ACCResult VisitObjCMessageExpr(ObjCMessageExpr *e) {
2669       return checkCallToMethod(e->getMethodDecl());
2670     }
2671 
VisitObjCPropertyRefExpr(ObjCPropertyRefExpr * e)2672     ACCResult VisitObjCPropertyRefExpr(ObjCPropertyRefExpr *e) {
2673       ObjCMethodDecl *method;
2674       if (e->isExplicitProperty())
2675         method = e->getExplicitProperty()->getGetterMethodDecl();
2676       else
2677         method = e->getImplicitPropertyGetter();
2678       return checkCallToMethod(method);
2679     }
2680 
checkCallToMethod(ObjCMethodDecl * method)2681     ACCResult checkCallToMethod(ObjCMethodDecl *method) {
2682       if (!method) return ACC_invalid;
2683 
2684       // Check for message sends to functions returning CF types.  We
2685       // just obey the Cocoa conventions with these, even though the
2686       // return type is CF.
2687       if (!isAnyRetainable(TargetClass) || !isCFType(method->getResultType()))
2688         return ACC_invalid;
2689 
2690       // If the method is explicitly marked not-retained, it's +0.
2691       if (method->hasAttr<CFReturnsNotRetainedAttr>())
2692         return ACC_plusZero;
2693 
2694       // If the method is explicitly marked as returning retained, or its
2695       // selector follows a +1 Cocoa convention, treat it as +1.
2696       if (method->hasAttr<CFReturnsRetainedAttr>())
2697         return ACC_plusOne;
2698 
2699       switch (method->getSelector().getMethodFamily()) {
2700       case OMF_alloc:
2701       case OMF_copy:
2702       case OMF_mutableCopy:
2703       case OMF_new:
2704         return ACC_plusOne;
2705 
2706       default:
2707         // Otherwise, treat it as +0.
2708         return ACC_plusZero;
2709       }
2710     }
2711   };
2712 }
2713 
2714 static bool
KnownName(Sema & S,const char * name)2715 KnownName(Sema &S, const char *name) {
2716   LookupResult R(S, &S.Context.Idents.get(name), SourceLocation(),
2717                  Sema::LookupOrdinaryName);
2718   return S.LookupName(R, S.TUScope, false);
2719 }
2720 
addFixitForObjCARCConversion(Sema & S,DiagnosticBuilder & DiagB,Sema::CheckedConversionKind CCK,SourceLocation afterLParen,QualType castType,Expr * castExpr,const char * bridgeKeyword,const char * CFBridgeName)2721 static void addFixitForObjCARCConversion(Sema &S,
2722                                          DiagnosticBuilder &DiagB,
2723                                          Sema::CheckedConversionKind CCK,
2724                                          SourceLocation afterLParen,
2725                                          QualType castType,
2726                                          Expr *castExpr,
2727                                          const char *bridgeKeyword,
2728                                          const char *CFBridgeName) {
2729   // We handle C-style and implicit casts here.
2730   switch (CCK) {
2731   case Sema::CCK_ImplicitConversion:
2732   case Sema::CCK_CStyleCast:
2733     break;
2734   case Sema::CCK_FunctionalCast:
2735   case Sema::CCK_OtherCast:
2736     return;
2737   }
2738 
2739   if (CFBridgeName) {
2740     Expr *castedE = castExpr;
2741     if (CStyleCastExpr *CCE = dyn_cast<CStyleCastExpr>(castedE))
2742       castedE = CCE->getSubExpr();
2743     castedE = castedE->IgnoreImpCasts();
2744     SourceRange range = castedE->getSourceRange();
2745     if (isa<ParenExpr>(castedE)) {
2746       DiagB.AddFixItHint(FixItHint::CreateInsertion(range.getBegin(),
2747                          CFBridgeName));
2748     } else {
2749       std::string namePlusParen = CFBridgeName;
2750       namePlusParen += "(";
2751       DiagB.AddFixItHint(FixItHint::CreateInsertion(range.getBegin(),
2752                                                     namePlusParen));
2753       DiagB.AddFixItHint(FixItHint::CreateInsertion(
2754                                        S.PP.getLocForEndOfToken(range.getEnd()),
2755                                        ")"));
2756     }
2757     return;
2758   }
2759 
2760   if (CCK == Sema::CCK_CStyleCast) {
2761     DiagB.AddFixItHint(FixItHint::CreateInsertion(afterLParen, bridgeKeyword));
2762   } else {
2763     std::string castCode = "(";
2764     castCode += bridgeKeyword;
2765     castCode += castType.getAsString();
2766     castCode += ")";
2767     Expr *castedE = castExpr->IgnoreImpCasts();
2768     SourceRange range = castedE->getSourceRange();
2769     if (isa<ParenExpr>(castedE)) {
2770       DiagB.AddFixItHint(FixItHint::CreateInsertion(range.getBegin(),
2771                          castCode));
2772     } else {
2773       castCode += "(";
2774       DiagB.AddFixItHint(FixItHint::CreateInsertion(range.getBegin(),
2775                                                     castCode));
2776       DiagB.AddFixItHint(FixItHint::CreateInsertion(
2777                                        S.PP.getLocForEndOfToken(range.getEnd()),
2778                                        ")"));
2779     }
2780   }
2781 }
2782 
2783 static void
diagnoseObjCARCConversion(Sema & S,SourceRange castRange,QualType castType,ARCConversionTypeClass castACTC,Expr * castExpr,ARCConversionTypeClass exprACTC,Sema::CheckedConversionKind CCK)2784 diagnoseObjCARCConversion(Sema &S, SourceRange castRange,
2785                           QualType castType, ARCConversionTypeClass castACTC,
2786                           Expr *castExpr, ARCConversionTypeClass exprACTC,
2787                           Sema::CheckedConversionKind CCK) {
2788   SourceLocation loc =
2789     (castRange.isValid() ? castRange.getBegin() : castExpr->getExprLoc());
2790 
2791   if (S.makeUnavailableInSystemHeader(loc,
2792                 "converts between Objective-C and C pointers in -fobjc-arc"))
2793     return;
2794 
2795   QualType castExprType = castExpr->getType();
2796 
2797   unsigned srcKind = 0;
2798   switch (exprACTC) {
2799   case ACTC_none:
2800   case ACTC_coreFoundation:
2801   case ACTC_voidPtr:
2802     srcKind = (castExprType->isPointerType() ? 1 : 0);
2803     break;
2804   case ACTC_retainable:
2805     srcKind = (castExprType->isBlockPointerType() ? 2 : 3);
2806     break;
2807   case ACTC_indirectRetainable:
2808     srcKind = 4;
2809     break;
2810   }
2811 
2812   // Check whether this could be fixed with a bridge cast.
2813   SourceLocation afterLParen = S.PP.getLocForEndOfToken(castRange.getBegin());
2814   SourceLocation noteLoc = afterLParen.isValid() ? afterLParen : loc;
2815 
2816   // Bridge from an ARC type to a CF type.
2817   if (castACTC == ACTC_retainable && isAnyRetainable(exprACTC)) {
2818 
2819     S.Diag(loc, diag::err_arc_cast_requires_bridge)
2820       << unsigned(CCK == Sema::CCK_ImplicitConversion) // cast|implicit
2821       << 2 // of C pointer type
2822       << castExprType
2823       << unsigned(castType->isBlockPointerType()) // to ObjC|block type
2824       << castType
2825       << castRange
2826       << castExpr->getSourceRange();
2827     bool br = KnownName(S, "CFBridgingRelease");
2828     {
2829       DiagnosticBuilder DiagB = S.Diag(noteLoc, diag::note_arc_bridge);
2830       addFixitForObjCARCConversion(S, DiagB, CCK, afterLParen,
2831                                    castType, castExpr, "__bridge ", 0);
2832     }
2833     {
2834       DiagnosticBuilder DiagB = S.Diag(noteLoc, diag::note_arc_bridge_transfer)
2835         << castExprType << br;
2836       addFixitForObjCARCConversion(S, DiagB, CCK, afterLParen,
2837                                    castType, castExpr, "__bridge_transfer ",
2838                                    br ? "CFBridgingRelease" : 0);
2839     }
2840 
2841     return;
2842   }
2843 
2844   // Bridge from a CF type to an ARC type.
2845   if (exprACTC == ACTC_retainable && isAnyRetainable(castACTC)) {
2846     bool br = KnownName(S, "CFBridgingRetain");
2847     S.Diag(loc, diag::err_arc_cast_requires_bridge)
2848       << unsigned(CCK == Sema::CCK_ImplicitConversion) // cast|implicit
2849       << unsigned(castExprType->isBlockPointerType()) // of ObjC|block type
2850       << castExprType
2851       << 2 // to C pointer type
2852       << castType
2853       << castRange
2854       << castExpr->getSourceRange();
2855 
2856     {
2857       DiagnosticBuilder DiagB = S.Diag(noteLoc, diag::note_arc_bridge);
2858       addFixitForObjCARCConversion(S, DiagB, CCK, afterLParen,
2859                                    castType, castExpr, "__bridge ", 0);
2860     }
2861     {
2862       DiagnosticBuilder DiagB = S.Diag(noteLoc, diag::note_arc_bridge_retained)
2863         << castType << br;
2864       addFixitForObjCARCConversion(S, DiagB, CCK, afterLParen,
2865                                    castType, castExpr, "__bridge_retained ",
2866                                    br ? "CFBridgingRetain" : 0);
2867     }
2868 
2869     return;
2870   }
2871 
2872   S.Diag(loc, diag::err_arc_mismatched_cast)
2873     << (CCK != Sema::CCK_ImplicitConversion)
2874     << srcKind << castExprType << castType
2875     << castRange << castExpr->getSourceRange();
2876 }
2877 
2878 Sema::ARCConversionResult
CheckObjCARCConversion(SourceRange castRange,QualType castType,Expr * & castExpr,CheckedConversionKind CCK)2879 Sema::CheckObjCARCConversion(SourceRange castRange, QualType castType,
2880                              Expr *&castExpr, CheckedConversionKind CCK) {
2881   QualType castExprType = castExpr->getType();
2882 
2883   // For the purposes of the classification, we assume reference types
2884   // will bind to temporaries.
2885   QualType effCastType = castType;
2886   if (const ReferenceType *ref = castType->getAs<ReferenceType>())
2887     effCastType = ref->getPointeeType();
2888 
2889   ARCConversionTypeClass exprACTC = classifyTypeForARCConversion(castExprType);
2890   ARCConversionTypeClass castACTC = classifyTypeForARCConversion(effCastType);
2891   if (exprACTC == castACTC) {
2892     // check for viablity and report error if casting an rvalue to a
2893     // life-time qualifier.
2894     if ((castACTC == ACTC_retainable) &&
2895         (CCK == CCK_CStyleCast || CCK == CCK_OtherCast) &&
2896         (castType != castExprType)) {
2897       const Type *DT = castType.getTypePtr();
2898       QualType QDT = castType;
2899       // We desugar some types but not others. We ignore those
2900       // that cannot happen in a cast; i.e. auto, and those which
2901       // should not be de-sugared; i.e typedef.
2902       if (const ParenType *PT = dyn_cast<ParenType>(DT))
2903         QDT = PT->desugar();
2904       else if (const TypeOfType *TP = dyn_cast<TypeOfType>(DT))
2905         QDT = TP->desugar();
2906       else if (const AttributedType *AT = dyn_cast<AttributedType>(DT))
2907         QDT = AT->desugar();
2908       if (QDT != castType &&
2909           QDT.getObjCLifetime() !=  Qualifiers::OCL_None) {
2910         SourceLocation loc =
2911           (castRange.isValid() ? castRange.getBegin()
2912                               : castExpr->getExprLoc());
2913         Diag(loc, diag::err_arc_nolifetime_behavior);
2914       }
2915     }
2916     return ACR_okay;
2917   }
2918 
2919   if (isAnyCLike(exprACTC) && isAnyCLike(castACTC)) return ACR_okay;
2920 
2921   // Allow all of these types to be cast to integer types (but not
2922   // vice-versa).
2923   if (castACTC == ACTC_none && castType->isIntegralType(Context))
2924     return ACR_okay;
2925 
2926   // Allow casts between pointers to lifetime types (e.g., __strong id*)
2927   // and pointers to void (e.g., cv void *). Casting from void* to lifetime*
2928   // must be explicit.
2929   if (exprACTC == ACTC_indirectRetainable && castACTC == ACTC_voidPtr)
2930     return ACR_okay;
2931   if (castACTC == ACTC_indirectRetainable && exprACTC == ACTC_voidPtr &&
2932       CCK != CCK_ImplicitConversion)
2933     return ACR_okay;
2934 
2935   switch (ARCCastChecker(Context, exprACTC, castACTC).Visit(castExpr)) {
2936   // For invalid casts, fall through.
2937   case ACC_invalid:
2938     break;
2939 
2940   // Do nothing for both bottom and +0.
2941   case ACC_bottom:
2942   case ACC_plusZero:
2943     return ACR_okay;
2944 
2945   // If the result is +1, consume it here.
2946   case ACC_plusOne:
2947     castExpr = ImplicitCastExpr::Create(Context, castExpr->getType(),
2948                                         CK_ARCConsumeObject, castExpr,
2949                                         0, VK_RValue);
2950     ExprNeedsCleanups = true;
2951     return ACR_okay;
2952   }
2953 
2954   // If this is a non-implicit cast from id or block type to a
2955   // CoreFoundation type, delay complaining in case the cast is used
2956   // in an acceptable context.
2957   if (exprACTC == ACTC_retainable && isAnyRetainable(castACTC) &&
2958       CCK != CCK_ImplicitConversion)
2959     return ACR_unbridged;
2960 
2961   diagnoseObjCARCConversion(*this, castRange, castType, castACTC,
2962                             castExpr, exprACTC, CCK);
2963   return ACR_okay;
2964 }
2965 
2966 /// Given that we saw an expression with the ARCUnbridgedCastTy
2967 /// placeholder type, complain bitterly.
diagnoseARCUnbridgedCast(Expr * e)2968 void Sema::diagnoseARCUnbridgedCast(Expr *e) {
2969   // We expect the spurious ImplicitCastExpr to already have been stripped.
2970   assert(!e->hasPlaceholderType(BuiltinType::ARCUnbridgedCast));
2971   CastExpr *realCast = cast<CastExpr>(e->IgnoreParens());
2972 
2973   SourceRange castRange;
2974   QualType castType;
2975   CheckedConversionKind CCK;
2976 
2977   if (CStyleCastExpr *cast = dyn_cast<CStyleCastExpr>(realCast)) {
2978     castRange = SourceRange(cast->getLParenLoc(), cast->getRParenLoc());
2979     castType = cast->getTypeAsWritten();
2980     CCK = CCK_CStyleCast;
2981   } else if (ExplicitCastExpr *cast = dyn_cast<ExplicitCastExpr>(realCast)) {
2982     castRange = cast->getTypeInfoAsWritten()->getTypeLoc().getSourceRange();
2983     castType = cast->getTypeAsWritten();
2984     CCK = CCK_OtherCast;
2985   } else {
2986     castType = cast->getType();
2987     CCK = CCK_ImplicitConversion;
2988   }
2989 
2990   ARCConversionTypeClass castACTC =
2991     classifyTypeForARCConversion(castType.getNonReferenceType());
2992 
2993   Expr *castExpr = realCast->getSubExpr();
2994   assert(classifyTypeForARCConversion(castExpr->getType()) == ACTC_retainable);
2995 
2996   diagnoseObjCARCConversion(*this, castRange, castType, castACTC,
2997                             castExpr, ACTC_retainable, CCK);
2998 }
2999 
3000 /// stripARCUnbridgedCast - Given an expression of ARCUnbridgedCast
3001 /// type, remove the placeholder cast.
stripARCUnbridgedCast(Expr * e)3002 Expr *Sema::stripARCUnbridgedCast(Expr *e) {
3003   assert(e->hasPlaceholderType(BuiltinType::ARCUnbridgedCast));
3004 
3005   if (ParenExpr *pe = dyn_cast<ParenExpr>(e)) {
3006     Expr *sub = stripARCUnbridgedCast(pe->getSubExpr());
3007     return new (Context) ParenExpr(pe->getLParen(), pe->getRParen(), sub);
3008   } else if (UnaryOperator *uo = dyn_cast<UnaryOperator>(e)) {
3009     assert(uo->getOpcode() == UO_Extension);
3010     Expr *sub = stripARCUnbridgedCast(uo->getSubExpr());
3011     return new (Context) UnaryOperator(sub, UO_Extension, sub->getType(),
3012                                    sub->getValueKind(), sub->getObjectKind(),
3013                                        uo->getOperatorLoc());
3014   } else if (GenericSelectionExpr *gse = dyn_cast<GenericSelectionExpr>(e)) {
3015     assert(!gse->isResultDependent());
3016 
3017     unsigned n = gse->getNumAssocs();
3018     SmallVector<Expr*, 4> subExprs(n);
3019     SmallVector<TypeSourceInfo*, 4> subTypes(n);
3020     for (unsigned i = 0; i != n; ++i) {
3021       subTypes[i] = gse->getAssocTypeSourceInfo(i);
3022       Expr *sub = gse->getAssocExpr(i);
3023       if (i == gse->getResultIndex())
3024         sub = stripARCUnbridgedCast(sub);
3025       subExprs[i] = sub;
3026     }
3027 
3028     return new (Context) GenericSelectionExpr(Context, gse->getGenericLoc(),
3029                                               gse->getControllingExpr(),
3030                                               subTypes.data(), subExprs.data(),
3031                                               n, gse->getDefaultLoc(),
3032                                               gse->getRParenLoc(),
3033                                        gse->containsUnexpandedParameterPack(),
3034                                               gse->getResultIndex());
3035   } else {
3036     assert(isa<ImplicitCastExpr>(e) && "bad form of unbridged cast!");
3037     return cast<ImplicitCastExpr>(e)->getSubExpr();
3038   }
3039 }
3040 
CheckObjCARCUnavailableWeakConversion(QualType castType,QualType exprType)3041 bool Sema::CheckObjCARCUnavailableWeakConversion(QualType castType,
3042                                                  QualType exprType) {
3043   QualType canCastType =
3044     Context.getCanonicalType(castType).getUnqualifiedType();
3045   QualType canExprType =
3046     Context.getCanonicalType(exprType).getUnqualifiedType();
3047   if (isa<ObjCObjectPointerType>(canCastType) &&
3048       castType.getObjCLifetime() == Qualifiers::OCL_Weak &&
3049       canExprType->isObjCObjectPointerType()) {
3050     if (const ObjCObjectPointerType *ObjT =
3051         canExprType->getAs<ObjCObjectPointerType>())
3052       if (ObjT->getInterfaceDecl()->isArcWeakrefUnavailable())
3053         return false;
3054   }
3055   return true;
3056 }
3057 
3058 /// Look for an ObjCReclaimReturnedObject cast and destroy it.
maybeUndoReclaimObject(Expr * e)3059 static Expr *maybeUndoReclaimObject(Expr *e) {
3060   // For now, we just undo operands that are *immediately* reclaim
3061   // expressions, which prevents the vast majority of potential
3062   // problems here.  To catch them all, we'd need to rebuild arbitrary
3063   // value-propagating subexpressions --- we can't reliably rebuild
3064   // in-place because of expression sharing.
3065   if (ImplicitCastExpr *ice = dyn_cast<ImplicitCastExpr>(e))
3066     if (ice->getCastKind() == CK_ARCReclaimReturnedObject)
3067       return ice->getSubExpr();
3068 
3069   return e;
3070 }
3071 
BuildObjCBridgedCast(SourceLocation LParenLoc,ObjCBridgeCastKind Kind,SourceLocation BridgeKeywordLoc,TypeSourceInfo * TSInfo,Expr * SubExpr)3072 ExprResult Sema::BuildObjCBridgedCast(SourceLocation LParenLoc,
3073                                       ObjCBridgeCastKind Kind,
3074                                       SourceLocation BridgeKeywordLoc,
3075                                       TypeSourceInfo *TSInfo,
3076                                       Expr *SubExpr) {
3077   ExprResult SubResult = UsualUnaryConversions(SubExpr);
3078   if (SubResult.isInvalid()) return ExprError();
3079   SubExpr = SubResult.take();
3080 
3081   QualType T = TSInfo->getType();
3082   QualType FromType = SubExpr->getType();
3083 
3084   CastKind CK;
3085 
3086   bool MustConsume = false;
3087   if (T->isDependentType() || SubExpr->isTypeDependent()) {
3088     // Okay: we'll build a dependent expression type.
3089     CK = CK_Dependent;
3090   } else if (T->isObjCARCBridgableType() && FromType->isCARCBridgableType()) {
3091     // Casting CF -> id
3092     CK = (T->isBlockPointerType() ? CK_AnyPointerToBlockPointerCast
3093                                   : CK_CPointerToObjCPointerCast);
3094     switch (Kind) {
3095     case OBC_Bridge:
3096       break;
3097 
3098     case OBC_BridgeRetained: {
3099       bool br = KnownName(*this, "CFBridgingRelease");
3100       Diag(BridgeKeywordLoc, diag::err_arc_bridge_cast_wrong_kind)
3101         << 2
3102         << FromType
3103         << (T->isBlockPointerType()? 1 : 0)
3104         << T
3105         << SubExpr->getSourceRange()
3106         << Kind;
3107       Diag(BridgeKeywordLoc, diag::note_arc_bridge)
3108         << FixItHint::CreateReplacement(BridgeKeywordLoc, "__bridge");
3109       Diag(BridgeKeywordLoc, diag::note_arc_bridge_transfer)
3110         << FromType << br
3111         << FixItHint::CreateReplacement(BridgeKeywordLoc,
3112                                         br ? "CFBridgingRelease "
3113                                            : "__bridge_transfer ");
3114 
3115       Kind = OBC_Bridge;
3116       break;
3117     }
3118 
3119     case OBC_BridgeTransfer:
3120       // We must consume the Objective-C object produced by the cast.
3121       MustConsume = true;
3122       break;
3123     }
3124   } else if (T->isCARCBridgableType() && FromType->isObjCARCBridgableType()) {
3125     // Okay: id -> CF
3126     CK = CK_BitCast;
3127     switch (Kind) {
3128     case OBC_Bridge:
3129       // Reclaiming a value that's going to be __bridge-casted to CF
3130       // is very dangerous, so we don't do it.
3131       SubExpr = maybeUndoReclaimObject(SubExpr);
3132       break;
3133 
3134     case OBC_BridgeRetained:
3135       // Produce the object before casting it.
3136       SubExpr = ImplicitCastExpr::Create(Context, FromType,
3137                                          CK_ARCProduceObject,
3138                                          SubExpr, 0, VK_RValue);
3139       break;
3140 
3141     case OBC_BridgeTransfer: {
3142       bool br = KnownName(*this, "CFBridgingRetain");
3143       Diag(BridgeKeywordLoc, diag::err_arc_bridge_cast_wrong_kind)
3144         << (FromType->isBlockPointerType()? 1 : 0)
3145         << FromType
3146         << 2
3147         << T
3148         << SubExpr->getSourceRange()
3149         << Kind;
3150 
3151       Diag(BridgeKeywordLoc, diag::note_arc_bridge)
3152         << FixItHint::CreateReplacement(BridgeKeywordLoc, "__bridge ");
3153       Diag(BridgeKeywordLoc, diag::note_arc_bridge_retained)
3154         << T << br
3155         << FixItHint::CreateReplacement(BridgeKeywordLoc,
3156                           br ? "CFBridgingRetain " : "__bridge_retained");
3157 
3158       Kind = OBC_Bridge;
3159       break;
3160     }
3161     }
3162   } else {
3163     Diag(LParenLoc, diag::err_arc_bridge_cast_incompatible)
3164       << FromType << T << Kind
3165       << SubExpr->getSourceRange()
3166       << TSInfo->getTypeLoc().getSourceRange();
3167     return ExprError();
3168   }
3169 
3170   Expr *Result = new (Context) ObjCBridgedCastExpr(LParenLoc, Kind, CK,
3171                                                    BridgeKeywordLoc,
3172                                                    TSInfo, SubExpr);
3173 
3174   if (MustConsume) {
3175     ExprNeedsCleanups = true;
3176     Result = ImplicitCastExpr::Create(Context, T, CK_ARCConsumeObject, Result,
3177                                       0, VK_RValue);
3178   }
3179 
3180   return Result;
3181 }
3182 
ActOnObjCBridgedCast(Scope * S,SourceLocation LParenLoc,ObjCBridgeCastKind Kind,SourceLocation BridgeKeywordLoc,ParsedType Type,SourceLocation RParenLoc,Expr * SubExpr)3183 ExprResult Sema::ActOnObjCBridgedCast(Scope *S,
3184                                       SourceLocation LParenLoc,
3185                                       ObjCBridgeCastKind Kind,
3186                                       SourceLocation BridgeKeywordLoc,
3187                                       ParsedType Type,
3188                                       SourceLocation RParenLoc,
3189                                       Expr *SubExpr) {
3190   TypeSourceInfo *TSInfo = 0;
3191   QualType T = GetTypeFromParser(Type, &TSInfo);
3192   if (!TSInfo)
3193     TSInfo = Context.getTrivialTypeSourceInfo(T, LParenLoc);
3194   return BuildObjCBridgedCast(LParenLoc, Kind, BridgeKeywordLoc, TSInfo,
3195                               SubExpr);
3196 }
3197