Ignoring GEM because its extensions are not built

Question

On both my work and home computers, I recently upgraded Ruby to 2.3.1, using ruby-install. I use chruby as my Ruby switcher.

I started seei

Answer 1

Adding my own flavor here. I use rbenv installed via Homebrew and was getting four of these "ignoring... extensions not built" messages. Specifically:

Ignoring bcrypt-3.1.12 because its extensions are not built.  Try: gem pristine bcrypt --version 3.1.12
Ignoring bindex-0.5.0 because its extensions are not built.  Try: gem pristine bindex --version 0.5.0
Ignoring bootsnap-1.3.2 because its extensions are not built.  Try: gem pristine bootsnap --version 1.3.2
Ignoring byebug-10.0.2 because its extensions are not built.  Try: gem pristine byebug --version 10.0.2

I tried many things in this thread with no luck. Finally in my case I did:

• brew uninstall rbenv
• rm -rf ~/.rbenv
• brew install rbenv

At this point I was still getting the errors, but now I had only a single Ruby version to contend with:

$ rbenv versions
* system (set by /Users/will/.rbenv/version)

At this point I tried sudo gem pristine --all but was rejected for permissions on the system Gems directory.

So I went through and ran pristine on each gem, like

sudo gem pristine bcrypt --version 3.1.12 (etc)

And finally the errors were gone.