On Fri, 4 Jun 2010, Jan Stary wrote:
'rm -rf /usr/obj/*' is not your arbitrary choice, it's a documented step when building the system. http://www.openbsd.org/faq/faq5.html#BldUserland
Also documented there is keeping /usr/obj/ in its own partition and using 'newfs' to zap everything more quickly.
/Lars
