> Is there a current GCC for MPW?

No.  The best we can do is 2.7.2 (after which Cygnus ruthlessly ripped
out all the stuff needed to compile under MacOS, leaving behind them a
mammoth task for anyone who might want to put it back in).

  http://www-sor.inria.fr/~piumarta/squeak/Jitter-3.1/devel/GCC.sit

I made a working gcc-2.95.2 ppc-elf (i.e. LinuxPPC) -> ppc-xcoff (i.e.
MacOS) cross compiler a few months ago, but failed to make a working
libgcc because of header nightmares.  (Even then I would have had to
do executable links with ppclink in MPW because it's apparently
impossible to turn a PEF back into an xcoff for linking.  Grrr!
[Anyone from Apple reading this??]).  At that point I lost interest
and stopped.

This would actually have been the the best development environment
imaginable: Linux for everything except final testing, which can be
done (without rebooting) under MOL from either an xmounted ext2 volume
or regular HFS mounted r/w under Linux.

Needless to say, a slightly modified version of the above story would
apply just as well to a MacOS-X -> MacOS cross compiler.

Ian