fails(JRUBY-5656):Array#pack with format 'U' taints the output string if the format string is tainted
fails(JRUBY-5656):Array#pack with format 'U' ignores NULL bytes between directives
fails(JRUBY-5656):Array#pack with format 'u' taints the output string if the format string is tainted
fails(JRUBY-5656):Array#pack with format 'u' raises a TypeError if passed nil
