objc - Treat type of 'self' in class methods as root of

class of this method. // rdar://10109725


git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@139989 91177308-0d34-0410-b5e6-96231b3b80d8

1 files changed, 20 insertions, 1 deletions

diff --git a/lib/Sema/SemaExpr.cpp b/lib/Sema/SemaExpr.cpp
index 2d80ac1265..715a4bd025 100644
--- a/lib/Sema/SemaExpr.cpp
+++ b/lib/Sema/SemaExpr.cpp
@@ -5074,6 +5074,23 @@ ExprResult Sema::ActOnConditionalOp(SourceLocation QuestionLoc,
                               OK));
 }
 
+/// SelfInClassMethodType - convet type of 'self' in class method
+/// to pointer to root of method's class.
+static void
+SelfInClassMethodType(Sema &S, Expr *selfExpr, QualType &SelfType) {
+  if (const ObjCMethodDecl *MD = S.GetMethodIfSelfExpr(selfExpr))
+    if (MD->isClassMethod()) {
+      const ObjCInterfaceDecl *Root = 0;
+      if (const ObjCInterfaceDecl * IDecl = MD->getClassInterface())
+      do {
+        Root = IDecl;
+      } while ((IDecl = IDecl->getSuperClass()));
+      if (Root)
+        SelfType = S.Context.getObjCObjectPointerType(
+                                                   S.Context.getObjCInterfaceType(Root)); 
+    }
+}
+
 // checkPointerTypesForAssignment - This is a very tricky routine (despite
 // being closely modeled after the C99 spec:-). The odd characteristic of this
 // routine is it effectively iqnores the qualifiers on the top level pointee.
@@ -5309,6 +5326,8 @@ Sema::CheckAssignmentConstraints(QualType LHSType, ExprResult &RHS,
     return Compatible;
   }
 
+  SelfInClassMethodType(*this, RHS.get(), RHSType);
+
   // If the left-hand side is a reference type, then we are in a
   // (rare!) case where we've allowed the use of references in C,
   // e.g., as a parameter type in a built-in function. In this case,
@@ -9564,7 +9583,7 @@ void Sema::DiagnoseAssignmentAsCondition(Expr *E) {
       Selector Sel = ME->getSelector();
 
       // self = [<foo> init...]
-      if (isSelfExpr(Op->getLHS()) && Sel.getNameForSlot(0).startswith("init"))
+      if (GetMethodIfSelfExpr(Op->getLHS()) && Sel.getNameForSlot(0).startswith("init"))
         diagnostic = diag::warn_condition_is_idiomatic_assignment;
 
       // <foo> = [<bar> nextObject]