If you go through the default profiles, you'll see this 'ENV_UNSET' variables which is something which is desired in custom profiles. Because in custom profiles, unlike with make.conf, make.default will NOT override variables inherited from the parent profile. It's additive/subtractive in nature. Therefore the following e.g. entries has to be done as a workaround -- L10N="en-US -en-AU -en-CA -en-GB -en-ZA en" VIDEO_CARDS="intel -amdgpu -dummy -fbdev -nouveau -radeon -radeonsi -vesa" SANE_BACKENDS="-abaton -agfafocus -apple -artec -artec_eplus48u -as6e -avision -bh -canon -canon630u -canon_dr -canon_lide70 -cardscan -coolscan -coolscan2 -coolscan3 -dc210 -dc240 -dc25 -dell1600n_net -dmc -epjitsu -epson -epson2 -epsonds -escl -fujitsu -genesys -gt68xx hp -hp3500 -hp3900 -hp4200 -hp5400 -hp5590 -hpljm1005 -hs2p -ibm -kodak -kodakaio -kvs1025 -kvs20xx -leo -lexmark -ma1509 -magicolor -matsushita -microtek -microtek2 -mustek -mustek_usb -nec -net -niash -p5 -pie -pieusb -pixma -plustek -plustek_pp -qcam -ricoh -ricoh2 -rts8891 -s9036 -sceptre -sharp -sm3600 -sm3840 -snapscan -sp15c -st400 -stv680 -tamarack -teco1 -teco2 -teco3 -test -u12 -umax -umax1220u -umax_pp -xerox_mfp" USE="opencl -brightness-control -wireless" Painful for upgrade. Instead ENV_UNSET must be documented and used for custom profiles. Reproducible: Always
It's documented in PMS at https://dev.gentoo.org/~ulm/pms/head/pms.html#section-5.3.2 but it isn't mentioned in a Portage man page.
