Thanks for the suggestion but everything is 64 bit.
I added this problem to the mars github issues list (there's an existing
issue for linux problems) and Esteban is now looking at it, so we're getting
somewhere.
The problem was I had no libgit-3.so in the folder only a libgit.so.0.
Unfortunately adding a symbolic link hasn't solved my problems. I now get a
VM crash. I've reported this along with the crash dump.
I'm sure it will be sorted eventually but I've been trying to get mars to
run on ubuntu since May - so progress is slow.