Error: Unbound module Topdirs

[UnixJunkie]

Error I get if I try to run an ocamlscript under a 5.1.0 ocaml switch.
It does not happen w/ earlier versions of ocaml.

[UnixJunkie]

Different problem w/ ocaml 5.0.0:
File "ocamlscript_main.ml", line 1:
Error: Cannot find file ~/.opam/5.0.0/lib/ocaml/threads.cmxa

[UnixJunkie]

problem does not happen w/ ocaml 4.14.1

[UnixJunkie]

Under ocaml 4.14.1:
ocamlfind: [WARNING] Package `threads': Linking problems may arise because of the missing -thread or -vmthread switch

[jrfondren]

@UnixJunkie I get a working ocamlscript in 5.4.0 by moving #use \"topfind\";; above the Topdirs use in main.ml
I also needed to install camlp4 with opam. A missing dependency?

[jrfondren]

OK, I get it. This was broken by OCaml in ocaml/ocaml#11979 where the fix is to add

#directory "+compiler-libs";

INSTALL also clearly notes the camlp4 dependency. I'm glad I waited until the Advent of Code sleepnessness wore off before I submitted a PR.