Using debugger-ruby_core_source fails to build native gem extension
This blog post was originally published a little while ago. Please consider that it may no longer be relevant or even accurate.
I just ran into an issue where my Rails app would no longer bundle, and I couldn't get it running. It all looks good up until it gets to
debugger-ruby_core_source and it fails to build gem native extension. If you've come across a similar problem you might be looking at something like this.
Turns out, this is simply a result of the debugger gem not supporting Ruby 2+. I find it odd that it is therefore still included with the
Gemfile that ships with Rails, but nonetheless if you want to replace the gem you might look at debugger2 or Pry.