After installing OPAL (Open Phone Abstraction Library) from Portage, the file /usr/share/opal/opal_inc.mak contains the line OPALDIR=/var/tmp/portage/opal-2.2.1/work/opal-2.2.1 which obviously isn't right because it refers to the temporary working directory of portage.
does not break anything, no need to fix this. You can write a fix and get it applied upstream if you feel that this is a bug and needs to be fixed.