bug#10828: [RFC] POSIX will say running "rm -f" with no argument is OK

[Karl Berry]

    > rm -f NOTFOUND $(VAR)
    i think this is an interesting route.  

I agree.

    we could do:
            rm -f $(am__rm_f_notfound) ...
    and am__rm_f_notfound could be set based on the configure test.

Sounds plausible to me. The "only" problem is that there are dozens or
hundreds of places in the code that do rm -f. They would all have to be
inspected and changed (or not) ... -k