[INFO] updating cached repository tuzz/supermutation
[INFO] running `"git" "fetch" "--all"`
[INFO] [stdout] Fetching origin
[INFO] [stderr] From git://github.com/tuzz/supermutation
[INFO] [stderr]  * branch            HEAD       -> FETCH_HEAD
[INFO] running `"git" "clone" "work/cache/sources/gh/tuzz/supermutation" "work/ex/beta-1.38-1/sources/1.37.0/gh/tuzz/supermutation"`
[INFO] [stderr] Cloning into 'work/ex/beta-1.38-1/sources/1.37.0/gh/tuzz/supermutation'...
[INFO] [stderr] done.
[INFO] running `"git" "clone" "work/cache/sources/gh/tuzz/supermutation" "work/ex/beta-1.38-1/sources/beta-2019-08-13/gh/tuzz/supermutation"`
[INFO] [stderr] Cloning into 'work/ex/beta-1.38-1/sources/beta-2019-08-13/gh/tuzz/supermutation'...
[INFO] [stderr] done.
[INFO] running `"git" "rev-parse" "HEAD"`
[INFO] [stdout] eafbd87c5cb2e3c1926035910f6f21323a976f03
[INFO] sha for GitHub repo tuzz/supermutation: eafbd87c5cb2e3c1926035910f6f21323a976f03
[INFO] validating manifest of tuzz/supermutation 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 tuzz/supermutation 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 tuzz/supermutation
[INFO] finished frobbing tuzz/supermutation
[INFO] frobbed toml for tuzz/supermutation written to work/ex/beta-1.38-1/sources/1.37.0/gh/tuzz/supermutation/Cargo.toml
[INFO] started frobbing tuzz/supermutation
[INFO] finished frobbing tuzz/supermutation
[INFO] frobbed toml for tuzz/supermutation written to work/ex/beta-1.38-1/sources/beta-2019-08-13/gh/tuzz/supermutation/Cargo.toml
[INFO] crate tuzz/supermutation 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 tuzz/supermutation against beta-2019-08-13 for beta-1.38-1
[INFO] running `"docker" "create" "-v" "/mnt/big/crater/work/local/target-dirs/beta-1.38-1/worker-5/beta-2019-08-13:/opt/crater/target:rw,Z" "-v" "/mnt/big/crater/work/ex/beta-1.38-1/sources/beta-2019-08-13/gh/tuzz/supermutation:/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" "+beta-2019-08-13" "build" "--frozen"`
[INFO] [stdout] 06cac48c6637203b8fc548f67eb3bfae491dde0ccc4ac5148477a8662d9aebaf
[INFO] running `"docker" "start" "-a" "06cac48c6637203b8fc548f67eb3bfae491dde0ccc4ac5148477a8662d9aebaf"`
[INFO] [stderr]    Compiling bindgen v0.37.4
[INFO] [stderr]    Compiling lehmer v3.0.0
[INFO] [stderr]    Compiling bucket_queue v2.0.0
[INFO] [stderr]    Compiling clang-sys v0.23.0
[INFO] [stderr]    Compiling libloading v0.5.0
[INFO] [stderr]    Compiling memchr v2.1.1
[INFO] [stderr]    Compiling which v1.0.5
[INFO] [stderr]    Compiling nom v3.2.1
[INFO] [stderr]    Compiling clap v2.32.0
[INFO] [stderr]    Compiling aho-corasick v0.6.9
[INFO] [stderr]    Compiling regex v1.0.6
[INFO] [stderr]    Compiling cexpr v0.2.3
[INFO] [stderr]    Compiling env_logger v0.5.13
[INFO] [stderr]    Compiling croaring-sys v0.3.7
[INFO] [stderr]    Compiling croaring v0.3.7
[INFO] [stderr]    Compiling supermutation v0.1.0 (/opt/crater/workdir)
[INFO] [stderr] error[E0554]: `#![feature]` may not be used on the beta release channel
[INFO] [stderr]  --> src/main.rs:1:1
[INFO] [stderr]   |
[INFO] [stderr] 1 | #![feature(uniform_paths)]
[INFO] [stderr]   | ^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stderr] 
[INFO] [stderr] error[E0554]: `#![feature]` may not be used on the beta release channel
[INFO] [stderr]  --> src/main.rs:2:1
[INFO] [stderr]   |
[INFO] [stderr] 2 | #![feature(drain_filter)]
[INFO] [stderr]   | ^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stderr] 
[INFO] [stderr] error: aborting due to 2 previous errors
[INFO] [stderr] 
[INFO] [stderr] For more information about this error, try `rustc --explain E0554`.
[INFO] [stderr] error: Could not compile `supermutation`.
[INFO] [stderr] 
[INFO] [stderr] To learn more, run the command again with --verbose.
[INFO] running `"docker" "inspect" "06cac48c6637203b8fc548f67eb3bfae491dde0ccc4ac5148477a8662d9aebaf"`
[INFO] running `"docker" "rm" "-f" "06cac48c6637203b8fc548f67eb3bfae491dde0ccc4ac5148477a8662d9aebaf"`
[INFO] [stdout] 06cac48c6637203b8fc548f67eb3bfae491dde0ccc4ac5148477a8662d9aebaf