Make binary build fully reproducible (at least on identical build machines)

[fingolfin]

Right now, if I rebuild the content of https://github.com/fingolfin/gap-osx-binary from scratch, on the same machine, I still get some diffs. I have not analyzed this in detail yet, but a typical cause are generated files which contain timestamps dependant on the build date (e.g. *.a archive files).

It would be nice to reduce these diffs as much as possible.

Some potentially relevant links:

• https://reproducible-builds.org
• https://wiki.debian.org/ReproducibleBuilds

[fingolfin]

Potentially useful tools:

• https://diffoscope.org/
• https://anonscm.debian.org/cgit/reproducible/strip-nondeterminism.git/

[fingolfin]

Updated URL: https://github.com/ReproducibleBuilds/strip-nondeterminism