[INFO] updating cached repository WillTer/rusty-cat
[INFO] running `"git" "fetch" "--all"`
[INFO] [stdout] Fetching origin
[INFO] [stderr] From git://github.com/WillTer/rusty-cat
[INFO] [stderr]  * branch            HEAD       -> FETCH_HEAD
[INFO] running `"git" "clone" "work/cache/sources/gh/WillTer/rusty-cat" "work/ex/beta-1.38-1/sources/1.37.0/gh/WillTer/rusty-cat"`
[INFO] [stderr] Cloning into 'work/ex/beta-1.38-1/sources/1.37.0/gh/WillTer/rusty-cat'...
[INFO] [stderr] done.
[INFO] running `"git" "clone" "work/cache/sources/gh/WillTer/rusty-cat" "work/ex/beta-1.38-1/sources/beta-2019-08-13/gh/WillTer/rusty-cat"`
[INFO] [stderr] Cloning into 'work/ex/beta-1.38-1/sources/beta-2019-08-13/gh/WillTer/rusty-cat'...
[INFO] [stderr] done.
[INFO] running `"git" "rev-parse" "HEAD"`
[INFO] [stdout] db25bf185847da8e620068ce64fe19e82c94cb7c
[INFO] sha for GitHub repo WillTer/rusty-cat: db25bf185847da8e620068ce64fe19e82c94cb7c
[INFO] validating manifest of WillTer/rusty-cat 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 WillTer/rusty-cat 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 WillTer/rusty-cat
[INFO] finished frobbing WillTer/rusty-cat
[INFO] frobbed toml for WillTer/rusty-cat written to work/ex/beta-1.38-1/sources/1.37.0/gh/WillTer/rusty-cat/Cargo.toml
[INFO] started frobbing WillTer/rusty-cat
[INFO] finished frobbing WillTer/rusty-cat
[INFO] frobbed toml for WillTer/rusty-cat written to work/ex/beta-1.38-1/sources/beta-2019-08-13/gh/WillTer/rusty-cat/Cargo.toml
[INFO] crate WillTer/rusty-cat 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] running `"/mnt/big/crater/work/local/cargo-home/bin/cargo" "+beta-2019-08-13" "fetch" "--locked" "--manifest-path" "Cargo.toml"`
[INFO] testing WillTer/rusty-cat against 1.37.0 for beta-1.38-1
[INFO] running `"docker" "create" "-v" "/mnt/big/crater/work/local/target-dirs/beta-1.38-1/worker-2/1.37.0:/opt/crater/target:rw,Z" "-v" "/mnt/big/crater/work/ex/beta-1.38-1/sources/1.37.0/gh/WillTer/rusty-cat:/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=warn" "-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" "+1.37.0" "build" "--frozen"`
[INFO] [stdout] 886feefe12b74f755212a70c046e9bda395c6d0e96f3a6683e88d7a561250da2
[INFO] running `"docker" "start" "-a" "886feefe12b74f755212a70c046e9bda395c6d0e96f3a6683e88d7a561250da2"`
[INFO] [stderr]    Compiling rusty-cat v0.1.0 (/opt/crater/workdir)
[INFO] [stderr] error[E0433]: failed to resolve: use of undeclared type or module `File`
[INFO] [stderr]   --> src/main.rs:60:20
[INFO] [stderr]    |
[INFO] [stderr] 60 |     let mut file = File::open(path)?;
[INFO] [stderr]    |                    ^^^^ use of undeclared type or module `File`
[INFO] [stderr] 
[INFO] [stderr] error: aborting due to previous error
[INFO] [stderr] 
[INFO] [stderr] For more information about this error, try `rustc --explain E0433`.
[INFO] [stderr] error: Could not compile `rusty-cat`.
[INFO] [stderr] 
[INFO] [stderr] To learn more, run the command again with --verbose.
[INFO] running `"docker" "inspect" "886feefe12b74f755212a70c046e9bda395c6d0e96f3a6683e88d7a561250da2"`
[INFO] running `"docker" "rm" "-f" "886feefe12b74f755212a70c046e9bda395c6d0e96f3a6683e88d7a561250da2"`
[INFO] [stdout] 886feefe12b74f755212a70c046e9bda395c6d0e96f3a6683e88d7a561250da2