Try to fix the coverall runs
Try to fix the coverall runs

djs55/ocaml-vchan,mirage/ocaml-vchan,samoht/ocaml-vchan,mirage/ocaml-vchan,samoht/ocaml-vchan,samoht/ocaml-vchan,djs55/ocaml-vchan,djs55/ocaml-vchan,mirage/ocaml-vchan