Issues with strictly confined snap (charm) on trusty

The strictly confined charm snap works fine on Xenial, but on Trusty it gives permission denied and bad system call errors.

Steps to reproduce:

sudo apt install snapd
sudo reboot now
sudo snap install charm

charm create foo  # fails with "bad system call"

git clone https://github.com/battlemidget/juju-charm-ghost/ ghost
cd ghost
charm build .  # fails with "permission denied"

The syslog during these commands is: https://pastebin.ubuntu.com/25522507/

The version difference between Xenial and Trusty is: https://pastebin.ubuntu.com/25522377/

Any help debugging this is appreciated.

For whatever reason on Ubuntu 14.04 snapd chose not to re-exec (however snap did re-exec correctly). I will also add that getting audit logs there is harder due to missing integration between journal and syslog (I think journal is just plain absent).

Trying again today, I’m not able to reproduce the issue. I get the proper version on snapd and everything works as expected. I’m not sure why it didn’t re-exec properly on the previous instance.