Re: [E] new compiler error re: SET-DISPATCH-MACRO-CHARACTER

I'm with Faré on this one. I don't see evidence that this change is because ASDF is doing something bad. I believe it's consistent with the hypothesis that there was some imperfectly-controlled aspect of building that is done differently now (e.g., files loaded in a different order where both orders are compatible with the constraints in the system definitions).

This doesn't even look like an ASDF error to me -- it looks like an error that occurred while loading a system that ASDF has re-packaged.

So we might be able to help you debug this, but without more evidence, there's no reason to believe that ASDF has done anything to you: it looks like the change in ASDF just reveals a pre-existing bug.