RubyInstaller-2.5.0-2 and RubyInstaller-2.4.3-2 fix a package conflict while
This issue is due to MSYS2 updates and caused
ridk install to fail since 2018-02-05.
See this bug report for more details.
There is no need to update, if you already have got a working MSYS2 setup.
All binaries are available in the Download section!