diff --git a/test/ruby/test_pattern_matching.rb b/test/ruby/test_pattern_matching.rb
index 3c4314bbe4..2afa823d53 100644
--- a/test/ruby/test_pattern_matching.rb
+++ b/test/ruby/test_pattern_matching.rb
@@ -1061,6 +1061,7 @@ END
             2}
         false
       in a: {b:}, c:
+        _b = b
         p c
       in {a:
       }