gcc via homebrew has no --without-multilib option

Question

I want to install xgboost in Python 3.5. This requires gcc to support -fopenmp option. Default gcc does not support it. So I am using

brew install gcc --without-multilib

But I get Warning: gcc: this formula has no '--without-multilib' option so it will be ignored! Any ideas?

Answer 1

The option no longer exists, since 8/2017. Many older 3rd-party xgboost instructions are outdated. Just do brew install gcc without options and be amazed that everything still works.