The Debian packaging of our RINA kernel builds with GCC 4.9,
which is not available on Stretch:

  # apt install ./linux-build-deps_4.1.33+rina65.g2e1cdbcb4-1_amd64.deb
  ...
  The following packages have unmet dependencies:
  linux-build-deps : Depends: gcc-4.9 but it is not installable