diff --git a/test/ruby/test_thread.rb b/test/ruby/test_thread.rb
index 6707fc4a29..3c10cce3c3 100644
--- a/test/ruby/test_thread.rb
+++ b/test/ruby/test_thread.rb
@@ -232,8 +232,8 @@ class TestThread < Test::Unit::TestCase
       Thread.pass
       t2 = Thread.new { loop { } }
       t3 = Thread.new { }.join
-      p [Thread.current, t1, t2].sort_by {|t| t.object_id }
-      p Thread.list.sort_by {|t| t.object_id }
+      p [Thread.current, t1, t2].map{|t| t.object_id }.sort
+      p Thread.list.map{|t| t.object_id }.sort
     INPUT
       assert_equal(r.first, r.last)
       assert_equal([], e)