Comment # 3 on bug 1038236 from Marcus R�ckert

please make sure all ruby 2.1 related packages are up2date. especially libruby*
and ruby*-stdlib

it should look like this:

$ rpm -q --qf "%{name}-%{version}-%{release} %{disturl}\n" libruby2_1-2_1
ruby2.1 ruby2.1-stdlib
libruby2_1-2_1-2.1.9-37.1
obs://build.opensuse.org/devel:languages:ruby/openSUSE_Leap_42.2/5074e244cee53f34fdee6bb60fe1f25c-ruby2.1
ruby2.1-2.1.9-37.1
obs://build.opensuse.org/devel:languages:ruby/openSUSE_Leap_42.2/5074e244cee53f34fdee6bb60fe1f25c-ruby2.1
ruby2.1-stdlib-2.1.9-37.1
obs://build.opensuse.org/devel:languages:ruby/openSUSE_Leap_42.2/5074e244cee53f34fdee6bb60fe1f25c-ruby2.1