git fetch --prune fails with "fatal: bad object"

git fetch --prune fails with "fatal: bad object" for refs that have an invalid sha1 pointer. It would be nice if "git fetch --prune" could prune these refs, because it is a hassle to do it manually. ("git fetch --prune" only shows the first invalid ref, and you have to run "git fsck" and parse it to find the rest.) If it seems like adding this functionality to --prune is a bad idea, then how about adding an option like "--prune-invalid" ?

Thanks.