diff --git a/test/ruby/test_require_lib.rb b/test/ruby/test_require_lib.rb
index 4af57173b8..d5a5df0817 100644
--- a/test/ruby/test_require_lib.rb
+++ b/test/ruby/test_require_lib.rb
@@ -8,6 +8,7 @@ class TestRequireLib < Test::Unit::TestCase
     # skip some problems
     next if %r!/lib/(?:bundler|rubygems)\b! =~ lib
     next if %r!/lib/(?:debug|mkmf)\.rb\z! =~ lib
+    next if %r!/lib/irb/ext/tracer\.rb\z! =~ lib
     # skip because "in `<module:Maker>': undefined method `add_maker' for RSS::Maker:Module (NoMethodError)"
     next if %r!/lib/rss\b! =~ lib
     # skip many files that almost use no threads