Gem Load Error is: unable to resolve type 'uintptr_t' for Ubuntu 16.04

[seantcanavan]

EDIT: If you install the win32-process ruby gem on Linux or OSX - you're going to have a bad time. Feel free to close. Apologies for the inconvenience.

I've installed ffi-1.9.14.gem, win32-process-0.8.3.gem, and vagrant-sshfs-1.2.0.gem plugins to vagrant which was recently upgraded to 1.8.6.

Now, when executing a vagrant command such as vagrant destroy, I receive:

$ vagrant destroy
Vagrant failed to initialize at a very early stage:

The plugins failed to load properly. The error message given is
shown below.

There was an error while trying to load the gem win32-process.
Gem Load Error is: unable to resolve type uintptr_t
Backtrace for gem load error is:
/opt/vagrant/embedded/gems/gems/ffi-1.9.14/lib/ffi/types.rb:69:in find_type
/opt/vagrant/embedded/gems/gems/ffi-1.9.14/lib/ffi/library.rb:446:in typedef
/home/user/.vagrant.d/gems/gems/win32-process-0.8.3/lib/win32/process/functions.rb:22:in module:Functions
/home/user/.vagrant.d/gems/gems/win32-process-0.8.3/lib/win32/process/functions.rb:8:in <top (required)>
/home/user/.vagrant.d/gems/gems/win32-process-0.8.3/lib/win32/process.rb:1:in require_relative
/home/user/.vagrant.d/gems/gems/win32-process-0.8.3/lib/win32/process.rb:1:in <top (required)>
/home/user/.vagrant.d/gems/gems/win32-process-0.8.3/lib/win32-process.rb:1:in require_relative
/home/user/.vagrant.d/gems/gems/win32-process-0.8.3/lib/win32-process.rb:1:in <top (required)>
/opt/vagrant/embedded/gems/gems/bundler-1.12.5/lib/bundler/runtime.rb:86:in require
/opt/vagrant/embedded/gems/gems/bundler-1.12.5/lib/bundler/runtime.rb:86:in block (2 levels) in require
/opt/vagrant/embedded/gems/gems/bundler-1.12.5/lib/bundler/runtime.rb:81:in each
/opt/vagrant/embedded/gems/gems/bundler-1.12.5/lib/bundler/runtime.rb:81:in block in require
/opt/vagrant/embedded/gems/gems/bundler-1.12.5/lib/bundler/runtime.rb:70:in each
/opt/vagrant/embedded/gems/gems/bundler-1.12.5/lib/bundler/runtime.rb:70:in require
/opt/vagrant/embedded/gems/gems/vagrant-1.8.6/lib/vagrant.rb:291:in <top (required)>
/opt/vagrant/embedded/gems/gems/vagrant-1.8.6/bin/vagrant:105:in require
/opt/vagrant/embedded/gems/gems/vagrant-1.8.6/bin/vagrant:105:in

Bundler Error Backtrace:

Apologies if this is a Vagrant issue and not an ffi issue. Still very new to vagrant / ruby / gems but have hit multiple road blocks on Ubuntu 16.04 so trying to get those highlighted and fixed asap.

Thanks,
Sean