commit ec8deba768e7ba93ad9974763dc3902896924a3c
author Fariborz Jahanian <fjahanian@apple.com> Thu Mar 28 19:50:55 2013 +0000
committer Fariborz Jahanian <fjahanian@apple.com> Thu Mar 28 19:50:55 2013 +0000
tree 7ec97819af944a583050ff48b1e208ae9ebb0e21
parent 5fd1fac0104e22533bc0284fdd0f42f843c975f5

Objective-C: Provide fixit suggestions when class object
is accessed via accessing 'isa' ivar to use
object_getClass/object_setClass apis.
// rdar://13503456


git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@178282 91177308-0d34-0410-b5e6-96231b3b80d8

lib/Sema/SemaExpr.cpp

diff --git a/lib/Sema/SemaExpr.cpp b/lib/Sema/SemaExpr.cpp
index 54422e8..238d833 100644
--- a/lib/Sema/SemaExpr.cpp
+++ b/lib/Sema/SemaExpr.cpp
@@ -491,8 +491,18 @@
   }
 
   CheckForNullPointerDereference(*this, E);
-  if (isa<ObjCIsaExpr>(E->IgnoreParens()))
-    Diag(E->getExprLoc(), diag::warn_objc_isa_use);
+  if (const ObjCIsaExpr *OISA = dyn_cast<ObjCIsaExpr>(E->IgnoreParenCasts())) {
+    NamedDecl *ObjectGetClass = LookupSingleName(TUScope,
+                                     &Context.Idents.get("object_getClass"),
+                                     SourceLocation(), LookupOrdinaryName);
+    if (ObjectGetClass)
+      Diag(E->getExprLoc(), diag::warn_objc_isa_use) <<
+        FixItHint::CreateInsertion(OISA->getLocStart(), "object_getClass(") <<
+        FixItHint::CreateReplacement(
+                    SourceRange(OISA->getOpLoc(), OISA->getIsaMemberLoc()), ")");
+    else
+      Diag(E->getExprLoc(), diag::warn_objc_isa_use);
+  }
 
   // C++ [conv.lval]p1:
   //   [...] If T is a non-class type, the type of the prvalue is the
@@ -8537,8 +8547,20 @@
   CheckArrayAccess(LHS.get());
   CheckArrayAccess(RHS.get());
 
-  if (isa<ObjCIsaExpr>(LHS.get()->IgnoreParens()))
-    Diag(LHS.get()->getExprLoc(), diag::warn_objc_isa_assign);
+  if (const ObjCIsaExpr *OISA = dyn_cast<ObjCIsaExpr>(LHS.get()->IgnoreParenCasts())) {
+    NamedDecl *ObjectSetClass = LookupSingleName(TUScope,
+                                                 &Context.Idents.get("object_setClass"),
+                                                 SourceLocation(), LookupOrdinaryName);
+    if (ObjectSetClass && isa<ObjCIsaExpr>(LHS.get())) {
+      SourceLocation RHSLocEnd = PP.getLocForEndOfToken(RHS.get()->getLocEnd());
+      Diag(LHS.get()->getExprLoc(), diag::warn_objc_isa_assign) <<
+      FixItHint::CreateInsertion(LHS.get()->getLocStart(), "object_setClass(") <<
+      FixItHint::CreateReplacement(SourceRange(OISA->getOpLoc(), OpLoc), ",") <<
+      FixItHint::CreateInsertion(RHSLocEnd, ")");
+    }
+    else
+      Diag(LHS.get()->getExprLoc(), diag::warn_objc_isa_assign);
+  }
 
   if (CompResultTy.isNull())
     return Owned(new (Context) BinaryOperator(LHS.take(), RHS.take(), Opc,

lib/Sema/SemaExprMember.cpp

diff --git a/lib/Sema/SemaExprMember.cpp b/lib/Sema/SemaExprMember.cpp
index e41a2e9..481c221 100644
--- a/lib/Sema/SemaExprMember.cpp
+++ b/lib/Sema/SemaExprMember.cpp
@@ -1132,6 +1132,7 @@
       // apparently.
       if (OTy->isObjCId() && Member->isStr("isa"))
         return Owned(new (Context) ObjCIsaExpr(BaseExpr.take(), IsArrow, MemberLoc,
+                                               OpLoc,
                                                Context.getObjCClassType()));
       if (ShouldTryAgainWithRedefinitionType(*this, BaseExpr))
         return LookupMemberExpr(R, BaseExpr, IsArrow, OpLoc, SS,

lib/Sema/TreeTransform.h

diff --git a/lib/Sema/TreeTransform.h b/lib/Sema/TreeTransform.h
index 1e424b6..e228d7a 100644
--- a/lib/Sema/TreeTransform.h
+++ b/lib/Sema/TreeTransform.h
@@ -2389,13 +2389,14 @@
   /// By default, performs semantic analysis to build the new expression.
   /// Subclasses may override this routine to provide different behavior.
   ExprResult RebuildObjCIsaExpr(Expr *BaseArg, SourceLocation IsaLoc,
+                                SourceLocation OpLoc,
                                       bool IsArrow) {
     CXXScopeSpec SS;
     ExprResult Base = getSema().Owned(BaseArg);
     LookupResult R(getSema(), &getSema().Context.Idents.get("isa"), IsaLoc,
                    Sema::LookupMemberName);
     ExprResult Result = getSema().LookupMemberExpr(R, Base, IsArrow,
-                                                         /*FIME:*/IsaLoc,
+                                                         OpLoc,
                                                          SS, 0, false);
     if (Result.isInvalid() || Base.isInvalid())
       return ExprError();
@@ -2404,7 +2405,7 @@
       return Result;
 
     return getSema().BuildMemberReferenceExpr(Base.get(), Base.get()->getType(),
-                                              /*FIXME:*/IsaLoc, IsArrow,
+                                              OpLoc, IsArrow,
                                               SS, SourceLocation(),
                                               /*FirstQualifierInScope=*/0,
                                               R,
@@ -8788,6 +8789,7 @@
     return SemaRef.Owned(E);
 
   return getDerived().RebuildObjCIsaExpr(Base.get(), E->getIsaMemberLoc(),
+                                         E->getOpLoc(),
                                          E->isArrow());
 }