[Unison-hackers] Building Compatible Unison: macOS + Raspbian

[Stéphane Glondu]

Dear David,

Le 23/08/2020 à 16:24, David Filip a écrit :
> So the latest version of Unison on macOS Brew is:
> 
>     $ unison -version
>     unison version 2.51.2 (ocaml 4.08.1)
> 
> [...]
> 
> So I download OCaml 4.08 to Raspbian, and successfully built and
> installed it:
> 
>     # ocaml -version
>     The OCaml toplevel, version 4.08.0

I would advise you to use the exact same version, 4.08.1. It is probably
easier to use opam.

> I then went back to Unison 2.51, and did a:
> 
>     # make clean
>     # make
> 
> 
> but whereas with OCaml 4.02 I just received a bunch of warnings, I now
> receive a fatal error when compiling Unison with OCaml 4.08 (to match
> the version that Unison on Brew was built with):
> 
>     ocamlopt: system.mli ---> system.cmi
>     ocamlopt -g -unsafe-string -I lwt -I ubase -I system -I fsmonitor -I
>     fsmonitor/linux -I fsmonitor/windows -I system/generic -I
>     lwt/generic -c /opt/unison-2.51.2/src/system.mli
>     ocamlopt: system.ml ---> system.cmx
>     ocamlopt -g -unsafe-string -I lwt -I ubase -I system -I fsmonitor -I
>     fsmonitor/linux -I fsmonitor/windows -I system/generic -I
>     lwt/generic -c /opt/unison-2.51.2/src/system.ml
>     *File "/opt/unison-2.51.2/src/system.ml", line 1*:
>     *Error*: The implementation /opt/unison-2.51.2/src/system.ml
>            does not match the interface system.cmi:
>            Values do not match:
>              val link : ?follow:bool -> string -> string -> unit
>            is not included in
>              val link : fspath -> fspath -> unit
>            *File "/opt/unison-2.51.2/src/system/system_intf.ml", line
>     70, characters 0-35*:
>              Expected declaration
>            *File "/opt/unison-2.51.2/src/system/system_generic.ml", line
>     50, characters 4-8*:
>              Actual declaration
>     Makefile.OCaml:422: recipe for target 'system.cmx' failed
>     make[1]: *** [system.cmx] Error 2
>     make[1]: Leaving directory '/opt/unison-2.51.2/src'
>     Makefile:6: recipe for target 'text' failed
>     make: *** [text] Error 2

Unison 2.51.2 does not compile with OCaml 4.08.1. In the following branch:

  https://github.com/glondu/unison/tree/unison-2.51

you will find a fix for that.

> Any ideas on how to fix this?  The Brew version of OCaml for macOS is
> actually 4.0.9.

This seems to contradict what you said above... unless Brew provides
binary packages that are not recompiled on each OCaml update.


Cheers,

-- 
Stéphane