Translations:Handbook:Parts/Portage/Files/45/en

Portage can create per-ebuild log files, but only when the PORT_LOGDIR variable is set to a location that is writable by portage (through the portage user). By default this variable is unset. If PORT_LOGDIR is not set, then there will not be any build logs with the current logging system, though users may receive some logs from the new  support.