I’m trying to install a compiler 4.07.1 but I get the error:
bot@06c94b204461:~$ opam switch create coq-8.12 4.07.1
<><> Gathering sources ><><><><><><><><><><><><><><><><><><><><><><><><><><><><>
[ocaml-base-compiler.4.07.1] found in cache
[ERROR] The sources of the following couldn't be obtained, aborting:
- ocaml-base-compiler.4.07.1
Switch initialisation failed: clean up? ('n' will leave the switch partially installed) [Y/n] Y
bot@06c94b204461:~$
bot@06c94b204461:~$ opam switch create coq-8.12 4.07.1^C
bot@06c94b204461:~$ opam switch
# switch compiler description
default ocaml-base-compiler.4.14.0 default
-> ocaml-variants.4.07.1+flambda_coq-serapi.8.11.0+0.11.1 ocaml-variants.4.07.1+flambda ocaml-variants.4.07.1+flambda_coq-serapi.8.11.0+0.11.1
bot@06c94b204461:~$
how do I fix this?