Gentoo's Bugzilla –
Attachment 426962 Details for
Bug 575970x11-drivers/xf86-video-intel with sys-libs/glibc-2.23 - .../work/d1672806a5222f00dcc2eb24ccddd03f727f71bc/tools/backlight_helper.c:54:2: error: implicit declaration of function ‘major’ [-Werror=implicit-function-declaration]