=march-x86-64-v3 on Intel 9700k in make.conf

[riot]

Is there any gains with using =march-x86-64-v3 over =march-native on a processor that supports x86-64-v3?

My make.conf looks like this now:

COMMON_FLAGS="-march=x86-64-v3 -mtune=native -O3 -pipe -flto"

[bstaletic]

More than likely, you won't notice any difference.
But! If you stick to x86_64-v3 and stable packages, you can set up a binhost and save yourself a lot of compiling.