1 files changed, 8 insertions, 0 deletions
diff --git a/test/dl/test_cptr.rb b/test/dl/test_cptr.rb
index 461b7d27d4..2a55a07dee 100644
--- a/test/dl/test_cptr.rb
+++ b/test/dl/test_cptr.rb
@@ -3,6 +3,14 @@ require_relative '../ruby/envutil'
 
 module DL
   class TestCPtr < TestBase
+    def test_ref_ptr
+      ary = [0,1,2,4,5]
+      addr = CPtr.new(dlwrap(ary))
+      assert_equal addr.to_i, addr.ref.ptr.to_i
+
+      assert_equal addr.to_i, (+ (- addr)).to_i
+    end
+
     def test_to_value
       ary = [0,1,2,4,5]
       addr = CPtr.new(dlwrap(ary))