Here's a strange non-crash. 

To set the stage, a make -j2 buildworld/buildkernel was run from a 
clean (run make cleandir twice, rm -rf /usr/obj/usr/src) start. Kernel
and sources were at, or close to, r331146.

Buildworld finished, but the kernel build failed on an error of long standing,
something about mismatches between various versions of stdint.h in the files
system. I ran svnlite update and found quite a bit of activity, so the
world/kernel build was restarted with -j2 and -DNO_CLEAN.

Some hours later, the system was found with all ssh sessions terminated
and the top output recorded in this directory. It looks as if the system
decided it was out of swap with 50-odd megs in use out of 3 GB, and then
went on a killing spree when lld.ld didn't go away. 

Is anybody able to self host -current in the last few weeks on an RPI3?