[INFO] updating cached repository mapmeld/rust-experiment
[INFO] running `"git" "fetch" "--all"`
[INFO] [stdout] Fetching origin
[INFO] [stderr] From git://github.com/mapmeld/rust-experiment
[INFO] [stderr]  * branch            HEAD       -> FETCH_HEAD
[INFO] running `"git" "clone" "work/cache/sources/gh/mapmeld/rust-experiment" "work/ex/pr-57967/sources/master#c1c3c4e95b69dfeaca5c5db6c622d7f90ad30a54/gh/mapmeld/rust-experiment"`
[INFO] [stderr] Cloning into 'work/ex/pr-57967/sources/master#c1c3c4e95b69dfeaca5c5db6c622d7f90ad30a54/gh/mapmeld/rust-experiment'...
[INFO] [stderr] done.
[INFO] running `"git" "clone" "work/cache/sources/gh/mapmeld/rust-experiment" "work/ex/pr-57967/sources/try#7fea0229842e79db1159ea58ad9a653b288efee9/gh/mapmeld/rust-experiment"`
[INFO] [stderr] Cloning into 'work/ex/pr-57967/sources/try#7fea0229842e79db1159ea58ad9a653b288efee9/gh/mapmeld/rust-experiment'...
[INFO] [stderr] done.
[INFO] running `"git" "rev-parse" "HEAD"`
[INFO] [stdout] 3f0590445d07ddf2c06b92dc84b99fd226c77ac1
[INFO] sha for GitHub repo mapmeld/rust-experiment: 3f0590445d07ddf2c06b92dc84b99fd226c77ac1
[INFO] validating manifest of mapmeld/rust-experiment on toolchain master#c1c3c4e95b69dfeaca5c5db6c622d7f90ad30a54
[INFO] running `"/mnt/big/crater/work/local/cargo-home/bin/cargo" "+c1c3c4e95b69dfeaca5c5db6c622d7f90ad30a54-alt" "read-manifest" "--manifest-path" "Cargo.toml"`
[INFO] validating manifest of mapmeld/rust-experiment on toolchain try#7fea0229842e79db1159ea58ad9a653b288efee9
[INFO] running `"/mnt/big/crater/work/local/cargo-home/bin/cargo" "+7fea0229842e79db1159ea58ad9a653b288efee9-alt" "read-manifest" "--manifest-path" "Cargo.toml"`
[INFO] started frobbing mapmeld/rust-experiment
[INFO] finished frobbing mapmeld/rust-experiment
[INFO] frobbed toml for mapmeld/rust-experiment written to work/ex/pr-57967/sources/master#c1c3c4e95b69dfeaca5c5db6c622d7f90ad30a54/gh/mapmeld/rust-experiment/Cargo.toml
[INFO] started frobbing mapmeld/rust-experiment
[INFO] finished frobbing mapmeld/rust-experiment
[INFO] frobbed toml for mapmeld/rust-experiment written to work/ex/pr-57967/sources/try#7fea0229842e79db1159ea58ad9a653b288efee9/gh/mapmeld/rust-experiment/Cargo.toml
[INFO] crate mapmeld/rust-experiment has a lockfile. skipping
[INFO] running `"/mnt/big/crater/work/local/cargo-home/bin/cargo" "+c1c3c4e95b69dfeaca5c5db6c622d7f90ad30a54-alt" "fetch" "--locked" "--manifest-path" "Cargo.toml"`
[INFO] [stderr] error: the lock file /mnt/big/crater/work/ex/pr-57967/sources/master#c1c3c4e95b69dfeaca5c5db6c622d7f90ad30a54/gh/mapmeld/rust-experiment/Cargo.lock needs to be updated but --locked was passed to prevent this
[ERROR] this task or one of its parent failed!
[ERROR] command `"/mnt/big/crater/work/local/cargo-home/bin/cargo" "+c1c3c4e95b69dfeaca5c5db6c622d7f90ad30a54-alt" "fetch" "--locked" "--manifest-path" "Cargo.toml"` failed