avoid "can't be called from trap context" errors in ThreadLocalVar
avoid "can't be called from trap context" errors in ThreadLocalVar

lucasallan/concurrent-ruby,hobodave/concurrent-ruby,hobodave/concurrent-ruby,hobodave/concurrent-ruby,lucasallan/concurrent-ruby,hobodave/concurrent-ruby,lucasallan/concurrent-ruby,lucasallan/concurrent-ruby,lucasallan/concurrent-ruby