Casualties of the cleanup were :feature and :if-component-dep-fails. They were just horrible things.
FYI, the sb-rotate-byte contrib in SBCL uses :if-component-dep-fails.
I've contacted the SBCL maintainers. Hopefully they will revert to #+x86-64 and such until a new asdf is universal. But that begs the question: how do we support old versions... and should we try?
I can imagine plenty of horribly klugy ways to make it work, but... ouch.
—♯ƒ • François-René ÐVB Rideau •Reflection&Cybernethics• http://fare.tunes.org I'd rather write programs that write programs than write programs — Dick Sites