This is mostly to yet another silly idea which turns out to be
possible. This may be actually useful should I implement more
sophisticated format specifiers like "%xd" or "%f".
Change-Id: Ia56cd6f5793a09fe5e19c91a8e8f9098f3244d57
Reviewed-on: https://cl.tvl.fyi/c/depot/+/3537
Tested-by: BuildkiteCI
Reviewed-by: sterni <sternenseemann@systemli.org>