flexdll software package provides OCaml cross-compiler based on mingw -- FlexDLL linker, you can install in your Debian 9 (Stretch) by running the commands given below on the terminal,
$ sudo apt-get update $ sudo apt-get install flexdll
flexdll is installed in your system.
Make ensure the flexdll package were installed using the commands given below,
$ sudo dpkg-query -l | grep flexdll *
You will get with flexdll package name, version, architecture and description in a table
| Distro | Debian 9 stretch |
| Section | Ocaml |
| Package | flexdll |
| Version | 4.01.0~20140328-1+b1 |
| Description | OCaml cross-compiler based on mingw -- FlexDLL linker |
| Sub Section | Ocaml |