I just wonder why this variable isn't adhered to anymore? this broke my current setup as it suddenly started to build things inside my portage cvs tree..... BUILD_PREFIX="${PORTAGE_TMPDIR}/build" where PORTAGE_TMPDIR is on its own partition (/ is limited in speed and size)... it wasn't pleasant :/
Set PORTAGE_TMPDIR instead. We now use more conservative variable expansion to prevent infinite expansion loops. One of the side-effects is that only variables defined earlier in the current config file can be expanded, which required us to remove BUILD_PREFIX and define it internally.
