I solved it. The error had to do with nokogiri. I installed it separately with the –use-system-libraries parameter: and I managed afterwards to install rails without errors.
This warnings appear because you are using ruby 2.4.0. This version introduced this change: Unify Fixnum and Bignum into Integer See here for the announcement: https://www.ruby-lang.org/en/news/2016/12/25/ruby-2-4-0-released/ The warnings come from the activesupport gem which is part of rails and will be fixed in an upcoming release. For now you can just ignore those warnings. Update: … Read more
I had a similar experience. Here’s how I solved it Display a list of all your local gems for the bundler gem N/B: The command above is for rbenv version manager, the one for rvm might be different This will display the versions of the bundler gem installed locally Note: Your versions might differ from … Read more
Note: While this answer has the desired effect, it does so by reducing overall security. The below answer by Alon is more correct and maintains the security of the site.