More info on GMP: https://gmplib.org/
To use GMP in a cross-compilation-friendly way, simply add this library in
your library dependencies and make sure it is locally fetched using the
opam-monorepo plugin (https://github.com/ocamllabs/opam-monorepo).
Example Dune configuration:
(library my_library)
(foreign_stubs (language c) (include_dirs (lib gmp)))
(libraries gmp)
...
)
This configuration enables the inclusion of gmp.h and the usage of gmp functions,
even in a cross-compiled environment such as MirageOS.