compiling-ocaml-5

This tutorial is known to be compatible with ocaml-5.2.0 under Crostini.

The command ln -s seem to produce an error, so it's still possible to use the LN=cp work-around.

In case you need to re-install the linux container, it's possible to install what you compliled in:

$ mkdir -p /mnt/chromeos/MyFiles/Console/usr/local

So the complete set of commands to install ocaml-5.2.0 can be:

$ mkdir -p /mnt/chromeos/MyFiles/Console/usr/local

$ sh configure --prefix=/mnt/chromeos/MyFiles/Console/usr/local

$ make LN=cp

$ make install LN=cp

$ cat /etc/os-release | grep -E '^(NAME=|VERSION_ID=)'
NAME="Debian GNU/Linux"
VERSION_ID="12"

Running the command ocaml will produce an error:

$ \ocaml
cannot execute: required file not found

But the command ocamlnat which is an equivalent toplevel doesn't produce any error.

Never-the-less, it seems it is not installed by default, so you only have to copy it:

$ cp ocamlnat /mnt/chromeos/MyFiles/Console/usr/local/bin/

Or if you prefer to install it with the install command:

$ /usr/bin/install -c -p -m 755 ocamlnat /mnt/chromeos/MyFiles/Console/usr/local/bin

If you selected a path which is not writable by the user at the configure step, you can just add sudo before the install command.

Then you can test your ocamlnat command:

$ ocamlnat
OCaml version 5.2.0 - native toplevel

# 

$ cat /tmp/hello.ml
print_endline "hello"

$ ocamlopt.opt -version
5.2.0

$ ocamlopt.opt -o /tmp/hello.opt /tmp/hello.ml

$ /tmp/hello.opt
hello

Don't forget to define some env-var's (environment-variables):

export CAML_LD_LIBRARY_PATH="/mnt/chromeos/MyFiles/Console/usr/local/lib/ocaml/stublibs"
export OCAMLPATH="/mnt/chromeos/MyFiles/Console/usr/local/lib/ocaml"
export OCAML_TOPLEVEL_PATH="/mnt/chromeos/MyFiles/Console/usr/local/lib/ocaml"
export LD_LIBRARY_PATH="/mnt/chromeos/MyFiles/Console/usr/local/lib/ocaml/stublibs:$LD_LIBRARY_PATH"
export PATH="/mnt/chromeos/MyFiles/Console/usr/local/bin:$PATH"

If you don't want to define it every-time you will use your ocaml-5 installation, you can add these env-vars into your ~/.bashrc file.

If you don't know yet how to edit a .txt file you can read this vim-tutorial.

Then if you want to use ocamlnat in stead of ocaml in a script, you can replace:

#!/usr/bin/env ocaml

by:

#!/usr/bin/env ocamlnat

At the first line of your script.

I hope you will be happy with your ocaml-5 software!

Happy ocaml'ing!

2025