Cabal 2.4 deprecates the default behaviours of previous versions, and
issues warnings whenever the usual cabal-install commands are used. This
is in preparation for future versions of Cabal where the usual commands
will have entirely new default behaviours. More work would be required
to update our SEL4.cabal configuration to these new behaviours. For now,
we avoid the warnings given by Cabal 2.4 by using the `v1-` versions of
cabal-install commands, which should continue to have the old behaviours
until they are removed from Cabal.
Gerwin Klein
Matthew Brecknell
Ilya Yanok