[INFO] updating cached repository sru/chip8-rust
[INFO] running `"git" "fetch" "--all"`
[INFO] [stdout] Fetching origin
[INFO] [stderr] From git://github.com/sru/chip8-rust
[INFO] [stderr]  * branch            HEAD       -> FETCH_HEAD
[INFO] running `"git" "clone" "work/cache/sources/gh/sru/chip8-rust" "work/ex/beta-1.38-1/sources/1.37.0/gh/sru/chip8-rust"`
[INFO] [stderr] Cloning into 'work/ex/beta-1.38-1/sources/1.37.0/gh/sru/chip8-rust'...
[INFO] [stderr] done.
[INFO] running `"git" "clone" "work/cache/sources/gh/sru/chip8-rust" "work/ex/beta-1.38-1/sources/beta-2019-08-13/gh/sru/chip8-rust"`
[INFO] [stderr] Cloning into 'work/ex/beta-1.38-1/sources/beta-2019-08-13/gh/sru/chip8-rust'...
[INFO] [stderr] done.
[INFO] running `"git" "rev-parse" "HEAD"`
[INFO] [stdout] e932f4237e4b34da010d3136e4b0424ff76d1984
[INFO] sha for GitHub repo sru/chip8-rust: e932f4237e4b34da010d3136e4b0424ff76d1984
[INFO] validating manifest of sru/chip8-rust 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 sru/chip8-rust 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 sru/chip8-rust
[INFO] finished frobbing sru/chip8-rust
[INFO] frobbed toml for sru/chip8-rust written to work/ex/beta-1.38-1/sources/1.37.0/gh/sru/chip8-rust/Cargo.toml
[INFO] started frobbing sru/chip8-rust
[INFO] finished frobbing sru/chip8-rust
[INFO] frobbed toml for sru/chip8-rust written to work/ex/beta-1.38-1/sources/beta-2019-08-13/gh/sru/chip8-rust/Cargo.toml
[INFO] crate sru/chip8-rust 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] error: the lock file /mnt/big/crater/work/ex/beta-1.38-1/sources/1.37.0/gh/sru/chip8-rust/Cargo.lock needs to be updated but --locked was passed to prevent this
[INFO] the lockfile is outdated, regenerating it
[INFO] running `"/mnt/big/crater/work/local/cargo-home/bin/cargo" "+1.37.0" "generate-lockfile" "--manifest-path" "Cargo.toml" "-Zno-index-update"`
[INFO] [stderr]     Blocking waiting for file lock on package cache
[INFO] running `"/mnt/big/crater/work/local/cargo-home/bin/cargo" "+beta-2019-08-13" "generate-lockfile" "--manifest-path" "Cargo.toml" "-Zno-index-update"`
[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 sru/chip8-rust 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-4/1.37.0:/opt/crater/target:rw,Z" "-v" "/mnt/big/crater/work/ex/beta-1.38-1/sources/1.37.0/gh/sru/chip8-rust:/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] ae0c42346930db6665ffe6971c6e487c3356307374858209464741f642b8f05d
[INFO] running `"docker" "start" "-a" "ae0c42346930db6665ffe6971c6e487c3356307374858209464741f642b8f05d"`
[INFO] [stderr]    Compiling chip8 v0.0.1 (/opt/crater/workdir)
[INFO] [stderr] error[E0432]: unresolved import `std::num::wrapping`
[INFO] [stderr]   --> src/lib.rs:13:15
[INFO] [stderr]    |
[INFO] [stderr] 13 | use std::num::wrapping::WrappingOps;
[INFO] [stderr]    |               ^^^^^^^^ could not find `wrapping` in `num`
[INFO] [stderr] 
[INFO] [stderr] error[E0554]: #![feature] may not be used on the stable release channel
[INFO] [stderr]  --> src/lib.rs:8:1
[INFO] [stderr]   |
[INFO] [stderr] 8 | #![feature(core)]
[INFO] [stderr]   | ^^^^^^^^^^^^^^^^^
[INFO] [stderr] 
[INFO] [stderr] error: aborting due to 2 previous errors
[INFO] [stderr] 
[INFO] [stderr] Some errors have detailed explanations: E0432, E0554.
[INFO] [stderr] For more information about an error, try `rustc --explain E0432`.
[INFO] [stderr] error: Could not compile `chip8`.
[INFO] [stderr] 
[INFO] [stderr] To learn more, run the command again with --verbose.
[INFO] running `"docker" "inspect" "ae0c42346930db6665ffe6971c6e487c3356307374858209464741f642b8f05d"`
[INFO] running `"docker" "rm" "-f" "ae0c42346930db6665ffe6971c6e487c3356307374858209464741f642b8f05d"`
[INFO] [stdout] ae0c42346930db6665ffe6971c6e487c3356307374858209464741f642b8f05d