Build failed on Raspberri Pi

[Tom Vijlbrief]

Do you have sufficient swap space allocated?

I have a 1GB swap area on a usb disk and I managed to build and install a
working world and kernel from a current src tree yesterday.

Under stress I still get aborted processes occasionally. Sshd, newsyslog,
sendmail. The weird thing is that the buildworld process tree itself was
never effected.

A gdb trace on one of the cores showed a single sbrk () line.

This bug is very subtle.