these 3 derivations will be built:
  /nix/store/d15w66vwi4s4an9yaqpmhg40vh0zm0f2-omp-18.12.3-cargo-vendor-vendor.drv
  /nix/store/gypyr9xqg8xpijz7pqmhs0v86dix764r-omp-18.12.3.drv
  /nix/store/0ipzyf92cdrf5gds91j5m3lw6f78g7jm-check-omp.drv