Currently there are two macros in /etc/rpm/macros.initrd:

%regenerate_initrd_post, to be called in the %post and %postun sections
and %regenerate_initrd_posttrans, to be called in %posttrans.

%regenerate_initrd_post simply sets a flag that the initrd has to be rebuilt
after the transaction. The posttrans macros takes care of that.

Now, that works fine for installation (%post -> %posttrans) and upgrades
(%postun -> %post -> %posttrans), but on removal, %posttrans is never run.

How could that be implemented properly?