diff --git a/test/ruby/test_notimp.rb b/test/ruby/test_notimp.rb
index 0ce0fc48a7..2a5a12a5f3 100644
--- a/test/ruby/test_notimp.rb
+++ b/test/ruby/test_notimp.rb
@@ -23,7 +23,7 @@ class TestNotImplement < Test::Unit::TestCase
   def test_call_fork
     pid = nil
     Timeout.timeout(1) {
-      pid = fork {sleep}
+      pid = fork {}
       Process.wait pid
       pid = nil
     }