Yes, that is right. parse-defsystem calls change-class. I will set up an issue for this, and put you on the cc list.

On 22 Dec 2021, at 10:49, Attila Lendvai wrote:

i think i know why this is happening.

i have attached a test that has the two versions that i have talked about. the slot override works, but the default-initarg doesn't.

ASDF probably calls change-class, probably from reset-system-class, which invokes reinitialize-instance directly, and somewhere here the default initargs are ignored.

but my CLOS is rusty.

is this a user bug, or an ADSF bug?

- attila