Error when installing rbczmq required by iruby in Windows - uninitialized constant GNU_CHAIN

Am trying to install rbczmq required by iruby on a windows machine and
this error keeps appearing. Am currently doing some deep learning and I
need to use sciruby and iruby to perform the actions required

PS C:> gem install iruby
Temporarily enhancing PATH to include DevKit…
Building native extensions.
This could take a while…
ERROR: Error installing iruby:
ERROR: Failed to build gem native extension.

C:/RailsInstaller/Ruby2.1.0/bin/ruby.exe -r

./siteconf20150710-76680-1u0zekx.rb extconf.rb
checking for windows.h… yes
checking for winsock.h… yes
checking for main() in -lkernel32… yes
checking for main() in -lrpcrt4… yes
checking for main() in -lgdi32… yes*** extconf.rb failed ***Could
not create Makefile due to some reason, probably lack of necessary
libraries and/or headers. Check the mkmf.log file for more details.
You may
need configuration options.
Provided configuration options:
extconf.rb:49:in `’: uninitialized constant GNU_CHAIN (NameError)

extconf failed, exit code 1

Gem files will remain installed in
C:/RailsInstaller/Ruby2.1.0/lib/ruby/gems/2.1.0/gems/rbczmq-1.7.9 for
Results logged to

Do you have DevKit installed?

Yea DevKit is installed