[INFO] updating cached repository DrDeano/backwards
[INFO] running `"git" "fetch" "--all"`
[INFO] [stdout] Fetching origin
[INFO] [stderr] From git://github.com/DrDeano/backwards
[INFO] [stderr]  * branch            HEAD       -> FETCH_HEAD
[INFO] running `"git" "clone" "work/cache/sources/gh/DrDeano/backwards" "work/ex/pr-60620-1/sources/master#ef01f29964df207f181bd5bcf236e41372a17273/gh/DrDeano/backwards"`
[INFO] [stderr] Cloning into 'work/ex/pr-60620-1/sources/master#ef01f29964df207f181bd5bcf236e41372a17273/gh/DrDeano/backwards'...
[INFO] [stderr] done.
[INFO] running `"git" "clone" "work/cache/sources/gh/DrDeano/backwards" "work/ex/pr-60620-1/sources/try#a7cff45e655f886da150e206c7acbe984df4ab71/gh/DrDeano/backwards"`
[INFO] [stderr] Cloning into 'work/ex/pr-60620-1/sources/try#a7cff45e655f886da150e206c7acbe984df4ab71/gh/DrDeano/backwards'...
[INFO] [stderr] done.
[INFO] running `"git" "rev-parse" "HEAD"`
[INFO] [stdout] a5722a6ad03b92bed20cb396f9bbd17d1c3ae97b
[INFO] sha for GitHub repo DrDeano/backwards: a5722a6ad03b92bed20cb396f9bbd17d1c3ae97b
[INFO] validating manifest of DrDeano/backwards on toolchain master#ef01f29964df207f181bd5bcf236e41372a17273
[INFO] running `"/mnt/big/crater/work/local/cargo-home/bin/cargo" "+ef01f29964df207f181bd5bcf236e41372a17273-alt" "read-manifest" "--manifest-path" "Cargo.toml"`
[INFO] validating manifest of DrDeano/backwards on toolchain try#a7cff45e655f886da150e206c7acbe984df4ab71
[INFO] running `"/mnt/big/crater/work/local/cargo-home/bin/cargo" "+a7cff45e655f886da150e206c7acbe984df4ab71-alt" "read-manifest" "--manifest-path" "Cargo.toml"`
[INFO] started frobbing DrDeano/backwards
[INFO] finished frobbing DrDeano/backwards
[INFO] frobbed toml for DrDeano/backwards written to work/ex/pr-60620-1/sources/master#ef01f29964df207f181bd5bcf236e41372a17273/gh/DrDeano/backwards/Cargo.toml
[INFO] started frobbing DrDeano/backwards
[INFO] finished frobbing DrDeano/backwards
[INFO] frobbed toml for DrDeano/backwards written to work/ex/pr-60620-1/sources/try#a7cff45e655f886da150e206c7acbe984df4ab71/gh/DrDeano/backwards/Cargo.toml
[INFO] crate DrDeano/backwards already has a lockfile, it will not be regenerated
[INFO] running `"/mnt/big/crater/work/local/cargo-home/bin/cargo" "+ef01f29964df207f181bd5bcf236e41372a17273-alt" "fetch" "--locked" "--manifest-path" "Cargo.toml"`
[INFO] [stderr]     Blocking waiting for file lock on package cache lock
[INFO] running `"/mnt/big/crater/work/local/cargo-home/bin/cargo" "+a7cff45e655f886da150e206c7acbe984df4ab71-alt" "fetch" "--locked" "--manifest-path" "Cargo.toml"`
[INFO] checking DrDeano/backwards against try#a7cff45e655f886da150e206c7acbe984df4ab71 for pr-60620-1
[INFO] running `"docker" "create" "-v" "/mnt/big/crater/work/local/target-dirs/pr-60620-1/worker-6/try#a7cff45e655f886da150e206c7acbe984df4ab71:/opt/crater/target:rw,Z" "-v" "/mnt/big/crater/work/ex/pr-60620-1/sources/try#a7cff45e655f886da150e206c7acbe984df4ab71/gh/DrDeano/backwards:/opt/crater/workdir:ro,Z" "-v" "/mnt/big/crater/work/local/cargo-home:/opt/crater/cargo-home:ro,Z" "-v" "/mnt/big/crater/work/local/rustup-home:/opt/crater/rustup-home:ro,Z" "-e" "USER_ID=1000" "-e" "SOURCE_DIR=/opt/crater/workdir" "-e" "MAP_USER_ID=1000" "-e" "CARGO_TARGET_DIR=/opt/crater/target" "-e" "CARGO_INCREMENTAL=0" "-e" "RUST_BACKTRACE=full" "-e" "RUSTFLAGS=--cap-lints=forbid" "-e" "CARGO_HOME=/opt/crater/cargo-home" "-e" "RUSTUP_HOME=/opt/crater/rustup-home" "-w" "/opt/crater/workdir" "-m" "1536M" "--network" "none" "rustops/crates-build-env" "/opt/crater/cargo-home/bin/cargo" "+a7cff45e655f886da150e206c7acbe984df4ab71-alt" "check" "--frozen" "--all" "--all-targets"`
[INFO] [stdout] 147138c061661e099b0bf1fa6aab44e361f268cc1b5542c4bbbb62d2ed2a0f97
[INFO] running `"docker" "start" "-a" "147138c061661e099b0bf1fa6aab44e361f268cc1b5542c4bbbb62d2ed2a0f97"`
[INFO] [stderr] error: failed to acquire package cache lock
[INFO] [stderr] 
[INFO] [stderr] Caused by:
[INFO] [stderr]   failed to open: /opt/crater/cargo-home/.package-cache
[INFO] [stderr] 
[INFO] [stderr] Caused by:
[INFO] [stderr]   Read-only file system (os error 30)
[INFO] running `"docker" "inspect" "147138c061661e099b0bf1fa6aab44e361f268cc1b5542c4bbbb62d2ed2a0f97"`
[INFO] running `"docker" "rm" "-f" "147138c061661e099b0bf1fa6aab44e361f268cc1b5542c4bbbb62d2ed2a0f97"`
[INFO] [stdout] 147138c061661e099b0bf1fa6aab44e361f268cc1b5542c4bbbb62d2ed2a0f97