Typhoeus 0.4.2 Memory Leak

Gemfile

source :rubygems

# no leak in version 0.3.3
# gem 'typhoeus', '0.3.3'

# memory leaking very fast (1Mb/s) in version 0.4.2
gem 'typhoeus', '0.4.2'

test.rb

#!/usr/bin/env ruby

require 'rubygems'
require 'typhoeus'

num_requests = 10_000
requests_per_iteration = 5

10_000.times do
  hydra = Typhoeus::Hydra.new
  requests_per_iteration.times do |i|
    hydra.queue(Typhoeus::Request.new("https://www.google.com?q=foo-#{i}"))
  end
  hydra.run

  # not necessary to reproduce, just to show that this not just
  # uncollected memory
  GC.start
end