bug#13002: Dealing with C intermediate files

[Karl Berry]

    quite exactly the same job that needs to be done

It's the same job, but lex and yacc are not at all the "same" as vala.
They are fundamental Unix utilities that have been around
forever. Whereas vala is a relatively recent invention, far less
ubiquitous. So I see no reason to treat them the same way.

Also, the point of having the lex/yacc .c files in make dist in the
first place is to reduce interdependencies among packages. But merely
distributing the .c files for vala does not seem likely tome to be enough
to actually eliminate the need for vala in practice.

Even if it is, looking to the future, it seems to me it would be better
to treat intermediate files as intermediate, and not distribute them in
make dist.  lex/yacc (and .info, etc.) have to be grandfathered in, but
creating new such special cases feels like a mistake to me. Every one of
the cases is a hassle in the code and causes plenty of confusion for
users. Let's not compound the problems. -k