diff --git a/ChangeLog b/ChangeLog
index 8b028a1d44..912984afb6 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,8 @@
+Wed Dec  9 06:25:47 2015  Eric Wong  <e@80x24.org>
+
+	* test/uri/test_generic.rb (to_s): new test
+	  [ruby-core:71820]
+
 Wed Dec  9 02:18:52 2015  Koichi Sasada  <ko1@atdot.net>
 
 	* compile.c (ibf_dump_memsize): should check NULL.
diff --git a/test/uri/test_generic.rb b/test/uri/test_generic.rb
index c0597b91dc..0a068c351b 100644
--- a/test/uri/test_generic.rb
+++ b/test/uri/test_generic.rb
@@ -14,6 +14,13 @@ class URI::TestGeneric < Test::Unit::TestCase
     uri.class.component.collect {|c| uri.send(c)}
   end
 
+  def test_to_s
+    exp = 'http://example.com/'.freeze
+    str = URI(exp).to_s
+    assert_equal exp, str
+    refute_predicate str, :frozen?, '[ruby-core:71785] [Bug #11759]'
+  end
+
   def test_parse
     # 0
     assert_kind_of(URI::HTTP, @base_url)