Horror Compiling OpenOffice.org or Hungry for Disc Space

Hikari is currently compiling away at OpenOffice.org. After finding out that TCSH was needed for a compile-stage, shaking my head in digust, and proceeding with the compile, I thought it would be relatively painless. I really did. But this compile’s been running for almost 14 hours now, and shows no signs of slowing. Now, CPU time isn’t a problem, and it taking another few days to compile would not be world-ending. However, a lot of disc is being used.. /usr/tmp/portage/openoffice-1.1.4 has already grown past 1.5GiB. This is leaving me currently with 227Mb free on the system partition. I havn’t installed the 80GiB data drive yet, but have another 1.7GiB partition already mounted and empty.

Is it actually possible to copy /usr over to another drive, delete it, and mount the other drive’s fs at /usr, without canceling the compile?