rspec で Ruby が segmentation fault 吐いた (Ruby: 2.0.0p195/2.0.0-p247, RSpec: 2.14.7)

segfault_spec.rb

require 'bundler/setup'

module ExtendModule
  def foo
    'foo'
  end

  def bar
    'bar'
  end
end

describe 'foo' do
  extend ExtendModule
  let(:foo) { foo }
  let(:bar) { bar }
  it { foo.should be 'foo' }
  it { bar.should be 'bar' }
end