From an user perspective, it's a bit annoying because the application does not stop nicely: dom0 was not informed that a domain terminated with an exception and when it tries to kill them, it will await forever... So it should not difficult and very nice to propagate the exception to dom0 and terminate nicely the program.
Currently, if a domain has an exception, it just shows the error and never terminate as we can see here: https://github.com/robur-coop/miou/blob/0560a14ea848466ea99792d27138c47f71aab747/lib/miou.ml#L1039-L1047
From an user perspective, it's a bit annoying because the application does not stop nicely:
dom0
was not informed that a domain terminated with an exception and when it tries to kill them, it will await forever... So it should not difficult and very nice to propagate the exception todom0
and terminate nicely the program.