Can not install json gem with ruby 2.2.3 on Ubuntu

Question

I am going through a Rails tutorial and I\'m not able to complete \'bundle install\' due to a problem with the json gem. When I attempt to install it directly:

Answer 1

Json 1.8.3 seems to have some issues with Ruby 2.2.3 (though I expect some future patches of Ruby will probably fix the problem). Downgrading Ruby to 2.2.2 worked for me.

(That said, so did sudo apt-get install libgmp3-dev, as @alf suggested - but if you're not able to do that, downgrading ruby might be a feasible alternative.)