> However, what I'd like is to keep the fill option turned on by default in
> every tool except named.
> 
> I'd quite like a compile-time option to have it be turned on by default in
> named, as well. Then we could have -M nofill or something to disable it.
> Having memory fill turned on by default when --enable-developer is in use
> seems like a good idea.

Implemented these suggestions and pushed to the branch. Please have a look.