Hi all,
We experienced a very annoying bug when updating to the new Ubuntu kernel 4.4.0-81-genericw which was performed in an unattended update of the server.
Building packages in R will create a core dump when lazy loading the package. It took some time to figure out that this is related to a bug affecting rJava.
We can confirm that rolling back to the previous kernel solved the issue. Yesterday there also seems to be and update of the kernel that solved this for some. We stick with the previous kernel version for now.