I havn't updated my system for few months and found i have to add new option to my make.conf. Ok, so now i have
CPU_FLAGS_X86="aes avx avx2 fma3 mmx mmxext popcnt sse sse2 sse3 sse4_1 sse4_2 ssse3"
But when
sudo emerge --update --newuse --deep --with-bdeps=y @world -p
I have rows like
[ebuild R ] media-sound/lame-3.99.5-r1 USE="-cpu_flags_x86_mmx%"
So it just ignores CPU USE FLAGS (e.g. -cpu_flags_x86_mmx) and hasn't special scope for CPU_FLAGS_X86. What's wrong?