[INFO] updating cached repository https://github.com/brb/coolc-rs
[INFO] running `"git" "-c" "credential.helper=" "-c" "credential.helper=/big/crater/work/cargo-home/bin/git-credential-null" "-c" "remote.origin.fetch=refs/heads/*:refs/heads/*" "fetch" "origin" "--force" "--prune"`
[INFO] running `"git" "rev-parse" "HEAD"`
[INFO] [stdout] b0819957478e39ece69cc82c68f298869cef9de4
[INFO] testing brb/coolc-rs against beta-2019-09-28 for beta-1.39-1
[INFO] running `"git" "clone" "work/cache/git-repos/https%3A%2F%2Fgithub.com%2Fbrb%2Fcoolc-rs" "work/builds/worker-7/source"`
[INFO] [stderr] Cloning into 'work/builds/worker-7/source'...
[INFO] [stderr] done.
[INFO] validating manifest of git repo https://github.com/brb/coolc-rs 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 git repo https://github.com/brb/coolc-rs
[INFO] finished tweaking git repo https://github.com/brb/coolc-rs
[INFO] tweaked toml for git repo https://github.com/brb/coolc-rs written to work/builds/worker-7/source/Cargo.toml
[INFO] crate git repo https://github.com/brb/coolc-rs already has a lockfile, it will not be regenerated
[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-7/target:/opt/rustwide/target:rw,Z" "-v" "/big/crater/work/builds/worker-7/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] e7aeff6d30c954ac70d4d39ec63e07461536715338545941d306b87c8250ec4a
[INFO] running `"docker" "start" "-a" "e7aeff6d30c954ac70d4d39ec63e07461536715338545941d306b87c8250ec4a"`
[INFO] [stderr]    Compiling coolc-rs v0.1.0 (/opt/rustwide/workdir)
[INFO] [stderr] error[E0432]: unresolved import `std::io::Chars`
[INFO] [stderr]  --> src/main.rs:3:5
[INFO] [stderr]   |
[INFO] [stderr] 3 | use std::io::Chars;
[INFO] [stderr]   |     ^^^^^^^^^^^^^^ no `Chars` in `io`
[INFO] [stderr] 
[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(io)]
[INFO] [stderr]   | ^^^^^^^^^^^^^^^
[INFO] [stderr] 
[INFO] [stderr] error[E0599]: no method named `chars` found for type `std::fs::File` in the current scope
[INFO] [stderr]    --> src/main.rs:295:41
[INFO] [stderr]     |
[INFO] [stderr] 295 |     let mut scanner = Scanner::new(file.chars());
[INFO] [stderr]     |                                         ^^^^^ method not found in `std::fs::File`
[INFO] [stderr] 
[INFO] [stderr] warning: unused import: `std::io::prelude`
[INFO] [stderr]  --> src/main.rs:4:5
[INFO] [stderr]   |
[INFO] [stderr] 4 | use std::io::prelude::*;
[INFO] [stderr]   |     ^^^^^^^^^^^^^^^^
[INFO] [stderr]   |
[INFO] [stderr]   = note: `#[warn(unused_imports)]` on by default
[INFO] [stderr] 
[INFO] [stderr] error: aborting due to 3 previous errors
[INFO] [stderr] 
[INFO] [stderr] Some errors have detailed explanations: E0432, E0554, E0599.
[INFO] [stderr] For more information about an error, try `rustc --explain E0432`.
[INFO] [stderr] error: could not compile `coolc-rs`.
[INFO] [stderr] 
[INFO] [stderr] To learn more, run the command again with --verbose.
[INFO] running `"docker" "inspect" "e7aeff6d30c954ac70d4d39ec63e07461536715338545941d306b87c8250ec4a"`
[INFO] running `"docker" "rm" "-f" "e7aeff6d30c954ac70d4d39ec63e07461536715338545941d306b87c8250ec4a"`
[INFO] [stdout] e7aeff6d30c954ac70d4d39ec63e07461536715338545941d306b87c8250ec4a