ocaml-mingw-w64-i686 binary package in Ubuntu Xenial amd64

 Objective Caml (OCaml) is an implementation of the ML language, based on
 the Caml Light dialect extended with a complete class-based object system
 and a powerful module system in the style of Standard ML.
 .
 OCaml comprises two compilers. One generates bytecode
 which is then interpreted by a C program. This compiler runs quickly,
 generates compact code with moderate memory requirements, and is
 portable to essentially any 32 or 64 bit Unix platform. Performance of
 generated programs is quite good for a bytecoded implementation:
 almost twice as fast as Caml Light 0.7. This compiler can be used
 either as a standalone, batch-oriented compiler that produces
 standalone programs, or as an interactive, toplevel-based system.
 .
 The other compiler generates high-performance native code for a number
 of processors. Compilation takes longer and generates bigger code, but
 the generated programs deliver excellent performance, while retaining
 the moderate memory requirements of the bytecode compiler. It is not
 available on all arches though.
 .
 This package contains everything needed to build OCaml code targeted
 to be executed under 32 bit windows.

Source package