Compile error: File "msgpackCore.ml", line 327, characters 15-16:

[skovhus]

Omake (omake.0.9.8.6-0.rc1) fails compiling mspack-ocaml:

• build ocaml msgpackCore.cmx
• ocamlfind ocamlopt -for-pack Msgpack -package oUnit,extlib,num -annot -annot -I . -c msgpackCore.ml File "msgpackCore.ml", line 327, characters 15-16: Error: This expression has type int but an expression was expected of type positive * omake: 87/133 targets are up to date
  * omake: failed (3 min 13.87 sec, 17/17 scans, 20/36 rules, 61/190 digests) *\ omake: targets were not rebuilt because of errors:
  ocaml/msgpackCore.cmx ocaml/msgpackCore.o

[mzp]

I could not receive its error message:

$ ocamlfind ocamlopt -for-pack Msgpack -package oUnit,extlib,num -annot -annot -I . -c msgpackCore.ml
$ echo $?
0

Please tell me your OCaml version.