[ocaml-ctypes] Undefined symbols error on OS X

[Jeremy Yallop]

Dear Travis,

On 17 February 2017 at 04:23, Travis <travis.brady at gmail.com> wrote:
> I'm attempting experimental OCaml bindings to Vowpal Wabbit and am stuck
> with the error here:
> https://gist.github.com/travisbrady/21a83ac57790455d4b9d545e8b18539a
>
> My code is visible at: https://github.com/travisbrady/ocaml-vw
>
> This is with OCaml 4.03.0, ctypes 0.11.3, Darwin 14.5.0 and libffi 3.0.13
> installed via Homebrew.
>
> After changing the package order manually I still get the error. Is it an
> issue with my code? Should I  install a more recent version of libffi?

This looks like it could be a name mangling error:

   Undefined symbols for architecture x86_64:
     "_VW_Initialize", referenced from:
         _vw_1_VW_Initialize in libvw_stubs.a(vw_stubs.o)
        (maybe you meant: _vw_1_VW_Initialize)
   ld: symbol(s) not found for architecture x86_64

Is it possible that the C linker is being used with a C++-only library?

Kind regards,

Jeremy