f372039d
### opam switch create test "--formula=[\"camlp4\" \"ocaml-system\"]" --show --yes

<><> Installing new switch packages <><><><><><><><><><><><><><><><><><><><><><>
Switch invariant: ["camlp4" "ocaml-system"]
[ERROR] Could not determine which packages to install for this switch:
  * Incompatible packages:
    - (invariant) -> camlp4
    - (invariant) -> ocaml-system
    You can temporarily relax the switch invariant with `--update-invariant'
  * Incompatible packages:
    - (invariant) -> camlp4 -> ocaml-variants (= 4.02.0+modular-implicits | = 4.02.1+modular-implicits-ber)
    - (invariant) -> ocaml-system
  * Incompatible packages:
    - (invariant) -> camlp4 -> ocaml < 4.08 -> ocaml-base-compiler (<= 3.07+1 | = 3.07+2 | = 3.08.0 | = 3.08.1 | = 3.08.2 | = 3.08.3 | = 3.08.4 | = 3.09.0 | = 3.09.1 | = 3.09.2 | = 3.09.3 | = 3.10.0 | = 3.10.1 | = 3.10.2 | = 3.11.0 | = 3.11.1 | = 3.11.2 | = 3.12.0 | = 3.12.1 | = 4.00.0 | = 4.00.1 | = 4.01.0 | = 4.02.0 | = 4.02.1 | = 4.02.2 | = 4.02.3 | = 4.03.0 | = 4.04.0 | = 4.04.1 | = 4.04.2 | = 4.05.0 | = 4.06.0 | = 4.06.1 | = 4.07.0 | = 4.07.1)
    - (invariant) -> ocaml-system
  * Incompatible packages:
    - (invariant) -> camlp4 -> ocaml < 4.08 -> ocaml-variants < 4.07.2~
    - (invariant) -> ocaml-system


# Return code 20 #
