diff --git a/ChangeLog b/ChangeLog
index 1c99e620c9..c38be22ede 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,8 @@
+Tue Sep  8 08:32:30 2009  Nobuyoshi Nakada  <nobu@ruby-lang.org>
+
+	* test/dl/test_{cfunc,ptr}.rb: added tests from Aaron Patterson.
+	  see [ruby-dev:39249].
+
 Mon Sep  7 17:22:59 2009  Nobuyoshi Nakada  <nobu@ruby-lang.org>
 
 	* io.c (rb_io_tell): adjustment for ungotten data.
diff --git a/test/dl/test_cfunc.rb b/test/dl/test_cfunc.rb
new file mode 100644
index 0000000000..9047c66b3c
--- /dev/null
+++ b/test/dl/test_cfunc.rb
@@ -0,0 +1,59 @@
+require 'test_base'
+require 'dl/func'
+
+module DL
+  class TestCFunc < TestBase
+    def setup
+      super
+      @name = 'strcpy'
+      @cf = CFunc.new(@libc[@name], TYPE_VOIDP, @name)
+    end
+
+    def test_new_ptr_type_name
+      assert_equal @name, @cf.name
+      assert @cf.name.tainted?, 'name should be tainted'
+      assert_equal :cdecl, @cf.calltype
+      assert_equal TYPE_VOIDP, @cf.ctype
+    end
+
+    def test_new_ptr
+      cf = CFunc.new(@libc['strcpy'])
+      assert_nil cf.name
+      assert_equal :cdecl, cf.calltype
+      assert_equal TYPE_VOID, cf.ctype
+    end
+
+    def test_name_should_be_duped
+      assert_equal @name, @cf.name
+      assert @cf.name.tainted?, 'name should be tainted'
+
+      name = @name.dup
+      @name << 'foo'
+
+      assert_equal name, @cf.name
+    end
+
+    def test_to_s
+      s = @cf.to_s
+      assert s.tainted?, 'to_s should be tainted'
+      assert_match(/ptr=#{sprintf("0x%x", @cf.ptr)}/, s)
+      assert_match(/name='#{@cf.name}'/, s)
+      assert_match(/type=#{@cf.ctype}/, s)
+    end
+
+    def test_inspect
+      assert_equal @cf.inspect, @cf.to_s
+    end
+
+    def test_to_i
+      assert_equal @cf.to_i, @cf.ptr
+    end
+
+    def test_last_error
+      f = Function.new(@cf, [TYPE_VOIDP, TYPE_VOIDP])
+      assert_nil CFunc.last_error
+      str = f.call("000", "123")
+      assert_not_nil CFunc.last_error
+    end
+  end
+end
diff --git a/test/dl/test_cptr.rb b/test/dl/test_cptr.rb
new file mode 100644
index 0000000000..3ff811f6e3
--- /dev/null
+++ b/test/dl/test_cptr.rb
@@ -0,0 +1,18 @@
+require 'test_base'
+
+module DL
+  class TestCPtr < TestBase
+    def test_free
+      ptr = CPtr.malloc(4)
+      assert_nil ptr.free
+    end
+
+    def test_free=
+      free = CFunc.new(@libc['free'], TYPE_VOID, 'free')
+      ptr = CPtr.malloc(4)
+      ptr.free = free
+
+      assert_equal free.ptr, ptr.free.ptr
+    end
+  end
+end