gcc 4.0 build failures on m68k, mips, and mipsel

Hi!

I noticed that PostgreSQL does not build any more with gcc 4.0 on
m68k, mips, and mipsel because of bugs/incompatibilities in
src/include/storage/s_lock.h.

Fixing m68k was easy, I attach the patch. gcc 4.0 seems to define both
__m68000___ and __m68k__, thus slock_t was defined twice. In 3.x,
__m68k__ was not defined, as it seems. So the patch should work for
both 3.x and 4.0.

However, since I don't have access to a mips/mipsel machine with gcc
4.0, I was unable to fix the problem myself, so I just disabled
spinlocks on these two architectures in Debian for now (which sucks,
but at least the package builds and works). Does anybody here have a
MIPS machine and could try this?

I'd love to give links to the build logs, unfortunately some Debian
servers are moving right now, thus buildd.debian.org is down. I'll
followup with the logs as soon as it is up again.

Thanks and have a nice day!

Martin
--
Martin Pitt        http://www.piware.de
Ubuntu Developer   http://www.ubuntu.com
Debian Developer   http://www.debian.org