Win7 (but it's irrelevant, all builds should do this)
Broken: latest master
Short description of error
When you add an integer socket to a cycles node-group, cycles is happy with it and it functions properly , however when you switch to the material view, blender instantly disappears with an access violation.
Exact steps for others to reproduce the error
Open the attached blend, switch to material view
I'm pretty sure this will end up in the 'not supported, don't do that' pile, but still it would be nice if we at-least not punish the user with an instant crash when this happens