[INFO] crate reckon 0.1.0 is already in cache
[INFO] testing reckon-0.1.0 against beta-2019-09-28 for beta-1.39-1
[INFO] extracting crate reckon 0.1.0 into work/builds/worker-2/source
[INFO] validating manifest of crates.io crate reckon 0.1.0 on toolchain beta-2019-09-28
[INFO] running `"/big/crater/work/cargo-home/bin/cargo" "+beta-2019-09-28" "read-manifest" "--manifest-path" "Cargo.toml"`
[INFO] started tweaking crates.io crate reckon 0.1.0
[INFO] finished tweaking crates.io crate reckon 0.1.0
[INFO] tweaked toml for crates.io crate reckon 0.1.0 written to work/builds/worker-2/source/Cargo.toml
[INFO] running `"/big/crater/work/cargo-home/bin/cargo" "+beta-2019-09-28" "generate-lockfile" "--manifest-path" "Cargo.toml" "-Zno-index-update"`
[INFO] running `"/big/crater/work/cargo-home/bin/cargo" "+beta-2019-09-28" "fetch" "--locked" "--manifest-path" "Cargo.toml"`
[INFO] running `"docker" "create" "-v" "/big/crater/work/builds/worker-2/target:/opt/rustwide/target:rw,Z" "-v" "/big/crater/work/builds/worker-2/source:/opt/rustwide/workdir:ro,Z" "-v" "/big/crater/work/cargo-home:/opt/rustwide/cargo-home:ro,Z" "-v" "/big/crater/work/rustup-home:/opt/rustwide/rustup-home:ro,Z" "-e" "SOURCE_DIR=/opt/rustwide/workdir" "-e" "MAP_USER_ID=1000" "-e" "CARGO_TARGET_DIR=/opt/rustwide/target" "-e" "CARGO_INCREMENTAL=0" "-e" "RUST_BACKTRACE=full" "-e" "RUSTFLAGS=--cap-lints=warn" "-e" "CARGO_HOME=/opt/rustwide/cargo-home" "-e" "RUSTUP_HOME=/opt/rustwide/rustup-home" "-w" "/opt/rustwide/workdir" "-m" "1610612736" "--network" "none" "rustops/crates-build-env" "/opt/rustwide/cargo-home/bin/cargo" "+beta-2019-09-28" "build" "--frozen"`
[INFO] [stdout] 53368a3983f08fbc1f04f6e3a534f63caff7f23764ab746a67eaa389e9e93b9d
[INFO] running `"docker" "start" "-a" "53368a3983f08fbc1f04f6e3a534f63caff7f23764ab746a67eaa389e9e93b9d"`
[INFO] [stderr]    Compiling reckon v0.1.0 (/opt/rustwide/workdir)
[INFO] [stderr] error[E0554]: `#![feature]` may not be used on the beta release channel
[INFO] [stderr]  --> src/lib.rs:9:1
[INFO] [stderr]   |
[INFO] [stderr] 9 | #![feature(io)]
[INFO] [stderr]   | ^^^^^^^^^^^^^^^
[INFO] [stderr] 
[INFO] [stderr] error[E0599]: no method named `chars` found for type `&mut std::process::ChildStdout` in the current scope
[INFO] [stderr]    --> src/base.rs:154:28
[INFO] [stderr]     |
[INFO] [stderr] 154 |         let mut c = stdout.chars();
[INFO] [stderr]     |                            ^^^^^ method not found in `&mut std::process::ChildStdout`
[INFO] [stderr] 
[INFO] [stderr] error: aborting due to 2 previous errors
[INFO] [stderr] 
[INFO] [stderr] Some errors have detailed explanations: E0554, E0599.
[INFO] [stderr] For more information about an error, try `rustc --explain E0554`.
[INFO] [stderr] error: could not compile `reckon`.
[INFO] [stderr] 
[INFO] [stderr] To learn more, run the command again with --verbose.
[INFO] running `"docker" "inspect" "53368a3983f08fbc1f04f6e3a534f63caff7f23764ab746a67eaa389e9e93b9d"`
[INFO] running `"docker" "rm" "-f" "53368a3983f08fbc1f04f6e3a534f63caff7f23764ab746a67eaa389e9e93b9d"`
[INFO] [stdout] 53368a3983f08fbc1f04f6e3a534f63caff7f23764ab746a67eaa389e9e93b9d