I've noticed the flag "--deterministic" but couldn't find an explanation. What are the reason someone wouldn't want a deterministic build from this?
bflat follows the platform convention that respects this and writes current date/time in the file header by default.
It is also a platform convention to offer options to set these to something stable (e.g. `/Brepro` on lld-link, or `--deterministic` for bflat) if one wants stable output.