[INFO] updating cached repository https://github.com/rust-lang-nursery/polonius
[INFO] running `"git" "-c" "credential.helper=" "-c" "credential.helper=/workspace/cargo-home/bin/git-credential-null" "-c" "remote.origin.fetch=refs/heads/*:refs/heads/*" "fetch" "origin" "--force" "--prune"`
[INFO] [stderr] From https://github.com/rust-lang-nursery/polonius
[INFO] [stderr]  + 823ef0f03b...557931ce87 gh-pages   -> gh-pages  (forced update)
[INFO] [stderr]    46b7c63dd1..c0dea8e66a  master     -> master
[INFO] running `"git" "rev-parse" "HEAD"`
[INFO] [stdout] c0dea8e66a4c72e96d010dd1627e54dbc244b9b7
[ERROR] this task or one of its parent failed!
[ERROR] command `"/workspace/cargo-home/bin/cargo" "+4007d4ef26eab44bdabc2b7574d032152264d3ad" "fetch" "--locked" "--manifest-path" "Cargo.toml"` failed
[ERROR] note: run with `RUST_BACKTRACE=1` to display a backtrace.