Re: plpython thinks it's hooked into "make distprep", but not so much

I wrote:
> I noticed while wrapping 9.1beta2 that plpython tries to build a file
> spiexceptions.h to be included in the tarballs, but no such file is
> actually appearing therein.  The reason is that src/pl/Makefile doesn't
> recurse into the plpython subdirectory unless with_python is set.
> Which it isn't, because the tarball build script doesn't configure
> --with-python (or with any other options for that matter).  If it did,
> it would fail, since there's no python installation on
> developer.postgresql.org.

> I left this go for the moment, since the only implication is that you
> have to have perl available to build plpython from the tarball.  But we
> oughta fix it before final.  Any opinions on what's the least ugly way
> to get control to recurse to src/pl/plpython for "make distprep"
> regardless of with_python?

> (More generally, I would like to see cleanup targets such as make
> distclean and make maintainer-clean recurse to all subdirectories
> regardless of configure options, but that might be too much to ask for
> right now.)

Attached is a proposed patch to fix this.  I found that the general
case was not too hard to solve, so this patch causes the make system
to recurse everywhere for distprep, clean, distclean, maintainer-clean
cases.  Anybody have a cleaner way to do it, or want to bikeshed on
the macro names?

			regards, tom lane