Determining Gentoo CPU_FLAGS_X86

Gentoo have recently taken the positive step of removing Intel-specific USE flags from builds directly, and introducing the new ‘CPU_FLAGS_X86‘ variable to control platform-specific hardware options.

(Presumably this opens the option for extensions such as ‘CPU_FLAGS_ARM="neon"‘, etc., in the future also…)

There is a new build app-portage/cpuinfo2cpuflags which will determine this information – but really, this feels like something that we can figure out canonically for ourselves without needing to pull-in additional packages 😉