diff --git a/test/ruby/test_trace.rb b/test/ruby/test_trace.rb
index d7a683b083..434da70107 100644
--- a/test/ruby/test_trace.rb
+++ b/test/ruby/test_trace.rb
@@ -63,6 +63,7 @@ class TestTrace < Test::Unit::TestCase
   def test_trace_stackoverflow
     assert_normal_exit("#{<<-"begin;"}\n#{<<~"end;"}", timeout: 60)
     begin;
+      require 'timeout'
       require 'tracer'
       class HogeError < StandardError
         def to_s
@@ -70,8 +71,16 @@ class TestTrace < Test::Unit::TestCase
         end
       end
       Tracer.stdout = open(IO::NULL, "w")
-      Tracer.on
-      HogeError.new.to_s
+      begin
+        Timeout.timeout(5) do
+          Tracer.on
+          HogeError.new.to_s
+        end
+      rescue Timeout::Error
+        # ok. there are no SEGV or critical error
+      rescue SystemStackError => e
+        # ok.
+      end
     end;
   end
 end