ensure_loadable_spec

# File lib/rubygems/installer.rb, line 527
  def ensure_loadable_spec
    ruby = spec.to_ruby_for_cache
    ruby.untaint

    begin
      eval ruby
    rescue StandardError, SyntaxError => e
      raise Gem::InstallError,
            "The specification for #{spec.full_name} is corrupt (#{e.class})"
    end
  end