diff --git a/test/ruby/test_gc.rb b/test/ruby/test_gc.rb
index a2ccc63218..53777c61a8 100644
--- a/test/ruby/test_gc.rb
+++ b/test/ruby/test_gc.rb
@@ -58,7 +58,7 @@ class TestGc < Test::Unit::TestCase
 
     GC.start # full mark and next time it should be minor mark
     GC.start(full_mark: false)
-    assert_nil GC.latest_gc_info(:major_by, msg)
+    assert_nil GC.latest_gc_info(:major_by)
 
     GC.start(full_mark: true)
     assert_not_nil GC.latest_gc_info(:major_by)