1 files changed, 19 insertions, 0 deletions
diff --git a/gcc/ada/exp_disp.adb b/gcc/ada/exp_disp.adb
index 99105e0..905311b 100644
--- a/gcc/ada/exp_disp.adb
+++ b/gcc/ada/exp_disp.adb
@@ -1138,6 +1138,25 @@ package body Exp_Disp is
          Operand_Typ := Base_Type (Corresponding_Record_Type (Operand_Typ));
       end if;
 
+      --  No displacement of the pointer to the object needed when the type of
+      --  the operand is not an interface type and the interface is one of
+      --  its parent types (since they share the primary dispatch table).
+
+      declare
+         Opnd : Entity_Id := Operand_Typ;
+
+      begin
+         if Is_Access_Type (Opnd) then
+            Opnd := Designated_Type (Opnd);
+         end if;
+
+         if not Is_Interface (Opnd)
+           and then Is_Ancestor (Iface_Typ, Opnd, Use_Full_View => True)
+         then
+            return;
+         end if;
+      end;
+
       --  Evaluate if we can statically displace the pointer to the object
 
       declare