[INFO] updating cached repository alanxi2322/CS1632-deliverable7
[INFO] running `"git" "fetch" "--all"`
[INFO] [stdout] Fetching origin
[INFO] [stderr] From git://github.com/alanxi2322/CS1632-deliverable7
[INFO] [stderr]  * branch            HEAD       -> FETCH_HEAD
[INFO] running `"git" "clone" "work/cache/sources/gh/alanxi2322/CS1632-deliverable7" "work/ex/beta-1.38-1/sources/1.37.0/gh/alanxi2322/CS1632-deliverable7"`
[INFO] [stderr] Cloning into 'work/ex/beta-1.38-1/sources/1.37.0/gh/alanxi2322/CS1632-deliverable7'...
[INFO] [stderr] done.
[INFO] running `"git" "clone" "work/cache/sources/gh/alanxi2322/CS1632-deliverable7" "work/ex/beta-1.38-1/sources/beta-2019-08-13/gh/alanxi2322/CS1632-deliverable7"`
[INFO] [stderr] Cloning into 'work/ex/beta-1.38-1/sources/beta-2019-08-13/gh/alanxi2322/CS1632-deliverable7'...
[INFO] [stderr] done.
[INFO] running `"git" "rev-parse" "HEAD"`
[INFO] [stdout] b1d3881174c077d983bf80721ba33d920ef56bb0
[INFO] sha for GitHub repo alanxi2322/CS1632-deliverable7: b1d3881174c077d983bf80721ba33d920ef56bb0
[INFO] validating manifest of alanxi2322/CS1632-deliverable7 on toolchain 1.37.0
[INFO] running `"/mnt/big/crater/work/local/cargo-home/bin/cargo" "+1.37.0" "read-manifest" "--manifest-path" "Cargo.toml"`
[INFO] validating manifest of alanxi2322/CS1632-deliverable7 on toolchain beta-2019-08-13
[INFO] running `"/mnt/big/crater/work/local/cargo-home/bin/cargo" "+beta-2019-08-13" "read-manifest" "--manifest-path" "Cargo.toml"`
[INFO] started frobbing alanxi2322/CS1632-deliverable7
[INFO] finished frobbing alanxi2322/CS1632-deliverable7
[INFO] frobbed toml for alanxi2322/CS1632-deliverable7 written to work/ex/beta-1.38-1/sources/1.37.0/gh/alanxi2322/CS1632-deliverable7/Cargo.toml
[INFO] started frobbing alanxi2322/CS1632-deliverable7
[INFO] finished frobbing alanxi2322/CS1632-deliverable7
[INFO] frobbed toml for alanxi2322/CS1632-deliverable7 written to work/ex/beta-1.38-1/sources/beta-2019-08-13/gh/alanxi2322/CS1632-deliverable7/Cargo.toml
[INFO] crate alanxi2322/CS1632-deliverable7 already has a lockfile, it will not be regenerated
[INFO] running `"/mnt/big/crater/work/local/cargo-home/bin/cargo" "+1.37.0" "fetch" "--locked" "--manifest-path" "Cargo.toml"`
[INFO] [stderr]     Updating git repository `https://github.com/rust-lang-nursery/rand`
[INFO] [stderr] error: failed to load source for a dependency on `rand`
[INFO] [stderr] 
[INFO] [stderr] Caused by:
[INFO] [stderr]   Unable to update https://github.com/rust-lang-nursery/rand#f2453707
[INFO] [stderr] 
[INFO] [stderr] Caused by:
[INFO] [stderr]   revspec 'f24537072f9d51cca153d9979181793015b81623' not found; class=Reference (4); code=NotFound (-3)
[ERROR] this task or one of its parent failed!
[ERROR] command `"/mnt/big/crater/work/local/cargo-home/bin/cargo" "+1.37.0" "fetch" "--locked" "--manifest-path" "Cargo.toml"` failed