Re: $(srcdir) in man pages and other targets

[Karl Berry]

    the point here is to also check that those files are not rebuilt, an
    information that is likely to be hard to find in a make distcheck.

Nevertheless, I believe automake checks it, via distclean.
>From (automake)Checking the Distribution --
  ... it's usually an error if your Makefiles cause some distributed
  files to be rebuilt when the user build the package.  (Think about
  the user missing the tool ...

I admit I didn't actually test if what automake does suffices for what
we're doing.  If more is needed, there is distcheck-hook to run
arbitrary commands ...

k