this derivation will be built:
  /nix/store/8d0f1gmczw4ij7sd7f9z240gnkpfhb57-harmonia-llvm-cov-3.1.0.drv
error: Cannot build '/nix/store/8d0f1gmczw4ij7sd7f9z240gnkpfhb57-harmonia-llvm-cov-3.1.0.drv'.
       Reason: builder failed with exit code 100.
       Output paths:
         /nix/store/bp00p7qii3c79dwc45w3g5ffh0ra0ag0-harmonia-llvm-cov-3.1.0
       Last 25 log lines:
       >         PASS [   0.605s] ( 794/2249) harmonia-cache::endpoints test_root_endpoint_with_signing_keys
       >         PASS [   0.613s] ( 795/2249) harmonia-cache::realisations test_build_trace_endpoint
       >         PASS [   0.620s] ( 796/2249) harmonia-cache::security_paths malformed_hash_is_4xx_not_5xx
       >         PASS [   0.635s] ( 797/2249) harmonia-cache::security_xss serve_directory_listing_escapes_filenames_in_href
       >         PASS [   0.636s] ( 798/2249) harmonia-cache::error_responses serve_missing_file_does_not_leak_fs_path
       >         PASS [   0.753s] ( 799/2249) harmonia-cache::log test_build_log_endpoint
       >         PASS [   0.769s] ( 800/2249) harmonia-cache::signing test_signing
       >         PASS [   0.850s] ( 801/2249) harmonia-cache::chroot test_chroot
       >         PASS [   2.325s] ( 802/2249) harmonia-file-nar archive::restorer::proptests::proptest_restore_dump
       >         PASS [   2.445s] ( 803/2249) harmonia-protocol ser::mock::proptests::proptest_mock
       >         PASS [  29.497s] ( 804/2249) harmonia-cache::retry test_download_retry_over_flaky_connection
       > ────────────
       >      Summary [  29.500s] 804/2249 tests run: 794 passed, 10 exec failed, 0 skipped
       >        XFAIL [   0.000s] ( 421/2249) harmonia-protocol ser::writer::unittests::test_write_slice::case_01_empty::chunks_size_04_4::buf_size_03_3
       >        XFAIL [   0.000s] ( 422/2249) harmonia-protocol ser::writer::unittests::test_write_slice::case_01_empty::chunks_size_04_4::buf_size_06_6
       >        XFAIL [   0.000s] ( 423/2249) harmonia-protocol ser::writer::unittests::test_write_slice::case_01_empty::chunks_size_04_4::buf_size_01_1
       >        XFAIL [   0.000s] ( 424/2249) harmonia-protocol ser::writer::unittests::test_write_slice::case_01_empty::chunks_size_04_4::buf_size_05_5
       >        XFAIL [   0.000s] ( 425/2249) harmonia-protocol ser::writer::unittests::test_write_slice::case_01_empty::chunks_size_04_4::buf_size_07_7
       >        XFAIL [   0.000s] ( 426/2249) harmonia-protocol ser::writer::unittests::test_write_slice::case_01_empty::chunks_size_04_4::buf_size_09_9
       >        XFAIL [   0.000s] ( 427/2249) harmonia-protocol ser::writer::unittests::test_write_slice::case_01_empty::chunks_size_04_4::buf_size_08_8
       >        XFAIL [   0.000s] ( 428/2249) harmonia-protocol ser::writer::unittests::test_write_slice::case_01_empty::chunks_size_05_5::buf_size_01_1
       >        XFAIL [   0.000s] ( 429/2249) harmonia-protocol ser::writer::unittests::test_write_slice::case_01_empty::chunks_size_05_5::buf_size_02_2
       >        XFAIL [   0.000s] ( 430/2249) harmonia-protocol ser::writer::unittests::test_write_slice::case_01_empty::chunks_size_04_4::buf_size_10_1024
       > warning: 1445/2249 tests were not run due to test failure (run with --no-fail-fast to run all tests, or run with --max-fail)
       > error: test run failed
       For full logs, run:
         nix log /nix/store/8d0f1gmczw4ij7sd7f9z240gnkpfhb57-harmonia-llvm-cov-3.1.0.drv