error: while evaluating anonymous function at /var/lib/ofborg/checkout/repo/38dca4e3aa6bca43ea96d2fcc04e8229/mr-est/eval-2-shlevy.ewr1.nix.ci/.gc-of-borg-outpaths.nix:35:12, called from /var/lib/ofborg/checkout/repo/38dca4e3aa6bca43ea96d2fcc04e8229/mr-est/eval-2-shlevy.ewr1.nix.ci/lib/attrsets.nix:199:52:
while evaluating the attribute 'clang-sierraHack' at /var/lib/ofborg/checkout/repo/38dca4e3aa6bca43ea96d2fcc04e8229/mr-est/eval-2-shlevy.ewr1.nix.ci/lib/attrsets.nix:199:44:
while evaluating 'g' at /var/lib/ofborg/checkout/repo/38dca4e3aa6bca43ea96d2fcc04e8229/mr-est/eval-2-shlevy.ewr1.nix.ci/lib/attrsets.nix:266:19, called from /var/lib/ofborg/checkout/repo/38dca4e3aa6bca43ea96d2fcc04e8229/mr-est/eval-2-shlevy.ewr1.nix.ci/lib/attrsets.nix:199:52:
while evaluating the attribute 'clang-sierraHack' at /var/lib/ofborg/checkout/repo/38dca4e3aa6bca43ea96d2fcc04e8229/mr-est/eval-2-shlevy.ewr1.nix.ci/lib/attrsets.nix:199:44:
while evaluating anonymous function at /var/lib/ofborg/checkout/repo/38dca4e3aa6bca43ea96d2fcc04e8229/mr-est/eval-2-shlevy.ewr1.nix.ci/pkgs/top-level/release-lib.nix:121:38, called from /var/lib/ofborg/checkout/repo/38dca4e3aa6bca43ea96d2fcc04e8229/mr-est/eval-2-shlevy.ewr1.nix.ci/lib/attrsets.nix:199:52:
while evaluating 'isDerivation' at /var/lib/ofborg/checkout/repo/38dca4e3aa6bca43ea96d2fcc04e8229/mr-est/eval-2-shlevy.ewr1.nix.ci/lib/attrsets.nix:295:18, called from /var/lib/ofborg/checkout/repo/38dca4e3aa6bca43ea96d2fcc04e8229/mr-est/eval-2-shlevy.ewr1.nix.ci/pkgs/top-level/release-lib.nix:123:10:
while evaluating the attribute 'clang-sierraHack' at /var/lib/ofborg/checkout/repo/38dca4e3aa6bca43ea96d2fcc04e8229/mr-est/eval-2-shlevy.ewr1.nix.ci/pkgs/top-level/all-packages.nix:6032:3:
while evaluating 'override' at /var/lib/ofborg/checkout/repo/38dca4e3aa6bca43ea96d2fcc04e8229/mr-est/eval-2-shlevy.ewr1.nix.ci/lib/customisation.nix:78:20, called from /var/lib/ofborg/checkout/repo/38dca4e3aa6bca43ea96d2fcc04e8229/mr-est/eval-2-shlevy.ewr1.nix.ci/pkgs/top-level/all-packages.nix:6032:22:
while evaluating 'makeOverridable' at /var/lib/ofborg/checkout/repo/38dca4e3aa6bca43ea96d2fcc04e8229/mr-est/eval-2-shlevy.ewr1.nix.ci/lib/customisation.nix:72:24, called from /var/lib/ofborg/checkout/repo/38dca4e3aa6bca43ea96d2fcc04e8229/mr-est/eval-2-shlevy.ewr1.nix.ci/lib/customisation.nix:78:29:
while evaluating anonymous function at /var/lib/ofborg/checkout/repo/38dca4e3aa6bca43ea96d2fcc04e8229/mr-est/eval-2-shlevy.ewr1.nix.ci/pkgs/build-support/cc-wrapper/default.nix:8:1, called from /var/lib/ofborg/checkout/repo/38dca4e3aa6bca43ea96d2fcc04e8229/mr-est/eval-2-shlevy.ewr1.nix.ci/lib/customisation.nix:74:12:
while evaluating the attribute 'binutils.override' at /var/lib/ofborg/checkout/repo/38dca4e3aa6bca43ea96d2fcc04e8229/mr-est/eval-2-shlevy.ewr1.nix.ci/pkgs/top-level/darwin-packages.nix:20:3:
while evaluating 'wrapBintoolsWith' at /var/lib/ofborg/checkout/repo/38dca4e3aa6bca43ea96d2fcc04e8229/mr-est/eval-2-shlevy.ewr1.nix.ci/pkgs/top-level/all-packages.nix:7039:22, called from /var/lib/ofborg/checkout/repo/38dca4e3aa6bca43ea96d2fcc04e8229/mr-est/eval-2-shlevy.ewr1.nix.ci/pkgs/top-level/darwin-packages.nix:20:14:
while evaluating 'callPackageWith' at /var/lib/ofborg/checkout/repo/38dca4e3aa6bca43ea96d2fcc04e8229/mr-est/eval-2-shlevy.ewr1.nix.ci/lib/customisation.nix:113:35, called from /var/lib/ofborg/checkout/repo/38dca4e3aa6bca43ea96d2fcc04e8229/mr-est/eval-2-shlevy.ewr1.nix.ci/pkgs/top-level/all-packages.nix:7039:67:
while evaluating 'makeOverridable' at /var/lib/ofborg/checkout/repo/38dca4e3aa6bca43ea96d2fcc04e8229/mr-est/eval-2-shlevy.ewr1.nix.ci/lib/customisation.nix:72:24, called from /var/lib/ofborg/checkout/repo/38dca4e3aa6bca43ea96d2fcc04e8229/mr-est/eval-2-shlevy.ewr1.nix.ci/lib/customisation.nix:117:8:
while evaluating anonymous function at /var/lib/ofborg/checkout/repo/38dca4e3aa6bca43ea96d2fcc04e8229/mr-est/eval-2-shlevy.ewr1.nix.ci/pkgs/build-support/bintools-wrapper/default.nix:8:1, called from /var/lib/ofborg/checkout/repo/38dca4e3aa6bca43ea96d2fcc04e8229/mr-est/eval-2-shlevy.ewr1.nix.ci/lib/customisation.nix:74:12:
while evaluating the attribute 'binutils-unwrapped' at /var/lib/ofborg/checkout/repo/38dca4e3aa6bca43ea96d2fcc04e8229/mr-est/eval-2-shlevy.ewr1.nix.ci/pkgs/top-level/darwin-packages.nix:15:3:
while evaluating 'callPackageWith' at /var/lib/ofborg/checkout/repo/38dca4e3aa6bca43ea96d2fcc04e8229/mr-est/eval-2-shlevy.ewr1.nix.ci/lib/customisation.nix:113:35, called from /var/lib/ofborg/checkout/repo/38dca4e3aa6bca43ea96d2fcc04e8229/mr-est/eval-2-shlevy.ewr1.nix.ci/pkgs/top-level/darwin-packages.nix:15:24:
while evaluating 'makeOverridable' at /var/lib/ofborg/checkout/repo/38dca4e3aa6bca43ea96d2fcc04e8229/mr-est/eval-2-shlevy.ewr1.nix.ci/lib/customisation.nix:72:24, called from /var/lib/ofborg/checkout/repo/38dca4e3aa6bca43ea96d2fcc04e8229/mr-est/eval-2-shlevy.ewr1.nix.ci/lib/customisation.nix:117:8:
while evaluating anonymous function at /var/lib/ofborg/checkout/repo/38dca4e3aa6bca43ea96d2fcc04e8229/mr-est/eval-2-shlevy.ewr1.nix.ci/pkgs/os-specific/darwin/binutils/default.nix:1:1, called from /var/lib/ofborg/checkout/repo/38dca4e3aa6bca43ea96d2fcc04e8229/mr-est/eval-2-shlevy.ewr1.nix.ci/lib/customisation.nix:74:12:
while evaluating the attribute 'cctools' at /var/lib/ofborg/checkout/repo/38dca4e3aa6bca43ea96d2fcc04e8229/mr-est/eval-2-shlevy.ewr1.nix.ci/pkgs/top-level/darwin-packages.nix:28:3:
while evaluating 'callPackageWith' at /var/lib/ofborg/checkout/repo/38dca4e3aa6bca43ea96d2fcc04e8229/mr-est/eval-2-shlevy.ewr1.nix.ci/lib/customisation.nix:113:35, called from /var/lib/ofborg/checkout/repo/38dca4e3aa6bca43ea96d2fcc04e8229/mr-est/eval-2-shlevy.ewr1.nix.ci/pkgs/top-level/darwin-packages.nix:28:13:
while evaluating 'makeOverridable' at /var/lib/ofborg/checkout/repo/38dca4e3aa6bca43ea96d2fcc04e8229/mr-est/eval-2-shlevy.ewr1.nix.ci/lib/customisation.nix:72:24, called from /var/lib/ofborg/checkout/repo/38dca4e3aa6bca43ea96d2fcc04e8229/mr-est/eval-2-shlevy.ewr1.nix.ci/lib/customisation.nix:117:8:
while evaluating anonymous function at /var/lib/ofborg/checkout/repo/38dca4e3aa6bca43ea96d2fcc04e8229/mr-est/eval-2-shlevy.ewr1.nix.ci/pkgs/os-specific/darwin/cctools/port.nix:1:1, called from /var/lib/ofborg/checkout/repo/38dca4e3aa6bca43ea96d2fcc04e8229/mr-est/eval-2-shlevy.ewr1.nix.ci/lib/customisation.nix:74:12:
while evaluating the attribute 'xcode_8_2.toolchain' at /var/lib/ofborg/checkout/repo/38dca4e3aa6bca43ea96d2fcc04e8229/mr-est/eval-2-shlevy.ewr1.nix.ci/pkgs/top-level/darwin-packages.nix:73:58:
attribute 'toolchain' missing, at /var/lib/ofborg/checkout/repo/38dca4e3aa6bca43ea96d2fcc04e8229/mr-est/eval-2-shlevy.ewr1.nix.ci/pkgs/top-level/darwin-packages.nix:32:19