these 3 derivations will be built:
  /nix/store/hq9dqfjrfp6s9cmmy21q7fkjz9pxivry-omp-18.4.6-cargo-vendor-vendor.drv
  /nix/store/6q7ngq76l3hyd3mdm73gbbvr3hzv2ml5-omp-18.4.6.drv
  /nix/store/8vyvibv0b85cmdh931n8vcv058sfcark-check-omp.drv