Update capnp-rpc-lwt.opam

[tmcgilchrist]

Testing the lower-bounds check for ocaml-ci

[talex5]

Looks good to me. Why is it a draft?

Would be interesting to know why the Windows build is failing, but looks unrelated to this PR:

  the following programs are not installed properly:
   curl
  I can't proceed :(

[tmcgilchrist]

@talex5 issue with setup-ocaml on Windows ocaml/setup-ocaml#645.

[tmcgilchrist]

This has a bug with the chosen lower bounds, the tests timeout. It is not clear whether it is caused by alcotest or dune. I am still debugging it by choosing newer versions of dependencies until it passes.

[talex5]

With a bit of testing locally, I see:

  capnp-rpc [WARNING] -----       : Uncaught async exception in "Message sender thread": (Invalid_argument Uint32.of_int)

[talex5]

This seems bad:

utop # #require "stdint";;
utop # let max_val = Stdint.Uint32.to_int (Stdint.Uint32.max_int);;
val max_val : int = -1

It seems to have been fixed by andrenth/ocaml-stdint@5e750d7 ("Migrate from jbuilder to dune"), which seems odd. Debugging it would require messing around with jbuilder, so probably capnproto just needs a lower-bound on stdint.

[talex5]

Thanks - I included your fixes in #266.