Processes dying with signal 11

[Bruce Cran]

I've been trying to run a buildworld using the clangbsd branch on my
G4 iBook, but without success. I'm currently running a fairly
up-to-date HEAD:

FreeBSD mac.draftnet 8.0-CURRENT #0: Tue Jun 16 22:07:11 BST 2009
brucec at mac.draftnet:/usr/obj/usr/src/sys/IBOOK powerpc

The problem I see is that after a few hours of running buildworld, when
it starts building clang itself, 'as' crashes with a signal 11.

I'm wondering if this is the normal case of bad memory/HDD/CPU or
something else because it also causes several other processes to crash,
notably dhclient and sendmail, but I've also seen tcsh crash too.  I
created a test program which allocated 500MB memory to force the system
into swap (my iBook only has 512MB).  After a few minutes dhclient
crashed but the test program kept running.  Is this what normally
happens when hardware's going bad?

-- 
Bruce