[INFO] updating cached repository u238/traits_exercise
[INFO] running `"git" "fetch" "--all"`
[INFO] [stdout] Fetching origin
[INFO] [stderr] From git://github.com/u238/traits_exercise
[INFO] [stderr]  * branch            HEAD       -> FETCH_HEAD
[INFO] running `"git" "clone" "work/cache/sources/gh/u238/traits_exercise" "work/ex/pr-60620/sources/master#ef01f29964df207f181bd5bcf236e41372a17273/gh/u238/traits_exercise"`
[INFO] [stderr] Cloning into 'work/ex/pr-60620/sources/master#ef01f29964df207f181bd5bcf236e41372a17273/gh/u238/traits_exercise'...
[INFO] [stderr] done.
[INFO] running `"git" "clone" "work/cache/sources/gh/u238/traits_exercise" "work/ex/pr-60620/sources/try#a7cff45e655f886da150e206c7acbe984df4ab71/gh/u238/traits_exercise"`
[INFO] [stderr] Cloning into 'work/ex/pr-60620/sources/try#a7cff45e655f886da150e206c7acbe984df4ab71/gh/u238/traits_exercise'...
[INFO] [stderr] done.
[INFO] running `"git" "rev-parse" "HEAD"`
[INFO] [stdout] b4d2ec668ba73d8123a0538c766117dbe9238423
[INFO] sha for GitHub repo u238/traits_exercise: b4d2ec668ba73d8123a0538c766117dbe9238423
[INFO] validating manifest of u238/traits_exercise on toolchain master#ef01f29964df207f181bd5bcf236e41372a17273
[INFO] running `"/mnt/crater-raid/crater/work/local/cargo-home/bin/cargo" "+ef01f29964df207f181bd5bcf236e41372a17273-alt" "read-manifest" "--manifest-path" "Cargo.toml"`
[INFO] validating manifest of u238/traits_exercise on toolchain try#a7cff45e655f886da150e206c7acbe984df4ab71
[INFO] running `"/mnt/crater-raid/crater/work/local/cargo-home/bin/cargo" "+a7cff45e655f886da150e206c7acbe984df4ab71-alt" "read-manifest" "--manifest-path" "Cargo.toml"`
[INFO] started frobbing u238/traits_exercise
[INFO] finished frobbing u238/traits_exercise
[INFO] frobbed toml for u238/traits_exercise written to work/ex/pr-60620/sources/master#ef01f29964df207f181bd5bcf236e41372a17273/gh/u238/traits_exercise/Cargo.toml
[INFO] started frobbing u238/traits_exercise
[INFO] finished frobbing u238/traits_exercise
[INFO] frobbed toml for u238/traits_exercise written to work/ex/pr-60620/sources/try#a7cff45e655f886da150e206c7acbe984df4ab71/gh/u238/traits_exercise/Cargo.toml
[INFO] crate u238/traits_exercise already has a lockfile, it will not be regenerated
[INFO] running `"/mnt/crater-raid/crater/work/local/cargo-home/bin/cargo" "+ef01f29964df207f181bd5bcf236e41372a17273-alt" "fetch" "--locked" "--manifest-path" "Cargo.toml"`
[INFO] running `"/mnt/crater-raid/crater/work/local/cargo-home/bin/cargo" "+a7cff45e655f886da150e206c7acbe984df4ab71-alt" "fetch" "--locked" "--manifest-path" "Cargo.toml"`
[INFO] checking u238/traits_exercise against master#ef01f29964df207f181bd5bcf236e41372a17273 for pr-60620
[INFO] running `"docker" "create" "-v" "/mnt/crater-raid/crater/work/local/target-dirs/pr-60620/worker-1/master#ef01f29964df207f181bd5bcf236e41372a17273:/opt/crater/target:rw,Z" "-v" "/mnt/crater-raid/crater/work/ex/pr-60620/sources/master#ef01f29964df207f181bd5bcf236e41372a17273/gh/u238/traits_exercise:/opt/crater/workdir:ro,Z" "-v" "/mnt/crater-raid/crater/work/local/cargo-home:/opt/crater/cargo-home:ro,Z" "-v" "/mnt/crater-raid/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" "+ef01f29964df207f181bd5bcf236e41372a17273-alt" "check" "--frozen" "--all" "--all-targets"`
[INFO] [stdout] 69ac779dab0afb01adc0388aaddc9c546003bdb92f6286fef4bcf7b44303eed0
[INFO] running `"docker" "start" "-a" "69ac779dab0afb01adc0388aaddc9c546003bdb92f6286fef4bcf7b44303eed0"`
[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" "69ac779dab0afb01adc0388aaddc9c546003bdb92f6286fef4bcf7b44303eed0"`
[INFO] running `"docker" "rm" "-f" "69ac779dab0afb01adc0388aaddc9c546003bdb92f6286fef4bcf7b44303eed0"`
[INFO] [stdout] 69ac779dab0afb01adc0388aaddc9c546003bdb92f6286fef4bcf7b44303eed0