staging is broken (again) with --enable-debugging-features on x86_64

Hi,

I looked at system.c but couldn't see what the problem was (the pword 
parameter is indeed used for __ia64__, but maybe there's a problem 
because it's an AMD Opteron machine).

In file included from libsablevm.c:80:
system.c: In function `_svmf_iflush':
system.c:37: warning: unused parameter `pword'
make[5]: *** [libsablevm.lo] Error 1

Log into magic.cs.mcgill.ca to test (you need libffi, classpath, and 
sablevm, but they all build very quickly with 'make -j5').

$ uname -a
Linux magic 2.6.7-gentoo-r1 #5 SMP Thu Jul 15 02:33:24 GMT 2004 x86_64 
AMD Opteron(tm) Processor 844 AuthenticAMD GNU/Linux

--disable-errors-on-warnings gets around it.

Cheers,
Chris