Hi,

Whilst working on the Reproducible Builds effort [0], we noticed that
libocamlviz-ocaml-doc could not be built reproducibly:

https://reproduce.debian.net/all/forky.html#libocamlviz-ocaml-doc

This is because the LaTeX-based documentation includes the current
build date. This can be specified to use SOURCE_DATE_EPOCH through the
LaTeX-specific FORCE_SOURCE_DATE environment variable.

Adding

export FORCE_SOURCE_DATE = 1

at the top of debian/rules makes the package reproducible.

 [0] https://reproducible-builds.org/

Cheers Jochen