[INFO] updating cached repository https://github.com/glowing-chemist/rustfck
[INFO] running `"git" "-c" "credential.helper=" "-c" "credential.helper=/workspace/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] 35eaf55cd08ec63de5358509f458247199cff89e
[INFO] testing glowing-chemist/rustfck against 1.44.0 for beta-1.45-1
[INFO] running `"git" "clone" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fglowing-chemist%2Frustfck" "/workspace/builds/worker-1/source"`
[INFO] [stderr] Cloning into '/workspace/builds/worker-1/source'...
[INFO] [stderr] done.
[INFO] validating manifest of git repo https://github.com/glowing-chemist/rustfck on toolchain 1.44.0
[INFO] running `"/workspace/cargo-home/bin/cargo" "+1.44.0" "read-manifest" "--manifest-path" "Cargo.toml"`
[INFO] started tweaking git repo https://github.com/glowing-chemist/rustfck
[INFO] finished tweaking git repo https://github.com/glowing-chemist/rustfck
[INFO] tweaked toml for git repo https://github.com/glowing-chemist/rustfck written to /workspace/builds/worker-1/source/Cargo.toml
[INFO] crate git repo https://github.com/glowing-chemist/rustfck already has a lockfile, it will not be regenerated
[INFO] running `"/workspace/cargo-home/bin/cargo" "+1.44.0" "fetch" "--locked" "--manifest-path" "Cargo.toml"`
[INFO] running `"docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-1/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-1/source:/opt/rustwide/workdir:ro,Z" "-v" "/var/lib/crater-agent-workspace/cargo-home:/opt/rustwide/cargo-home:ro,Z" "-v" "/var/lib/crater-agent-workspace/rustup-home:/opt/rustwide/rustup-home:ro,Z" "-e" "SOURCE_DIR=/opt/rustwide/workdir" "-e" "MAP_USER_ID=0" "-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" "+1.44.0" "build" "--frozen"`
[INFO] [stderr] WARNING: Your kernel does not support swap limit capabilities or the cgroup is not mounted. Memory limited without swap.
[INFO] [stdout] 0b5ea704540d87d21d1da0012f5cb677c1333a14853b1f0bf46d7fa8c022e9d3
[INFO] running `"docker" "start" "-a" "0b5ea704540d87d21d1da0012f5cb677c1333a14853b1f0bf46d7fa8c022e9d3"`
[INFO] [stderr] sudo: setrlimit(RLIMIT_CORE): Operation not permitted
[INFO] [stderr]    Compiling brainfuck v0.1.0 (/opt/rustwide/workdir)
[INFO] [stderr] error[E0554]: `#![feature]` may not be used on the stable 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 struct `std::fs::File` in the current scope
[INFO] [stderr]   --> src/main.rs:49:16
[INFO] [stderr]    |
[INFO] [stderr] 49 |     for c in f.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:3:5
[INFO] [stderr]   |
[INFO] [stderr] 3 | 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 2 previous errors; 1 warning emitted
[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 `brainfuck`.
[INFO] [stderr] 
[INFO] [stderr] To learn more, run the command again with --verbose.
[INFO] running `"docker" "inspect" "0b5ea704540d87d21d1da0012f5cb677c1333a14853b1f0bf46d7fa8c022e9d3"`
[INFO] running `"docker" "rm" "-f" "0b5ea704540d87d21d1da0012f5cb677c1333a14853b1f0bf46d7fa8c022e9d3"`
[INFO] [stdout] 0b5ea704540d87d21d1da0012f5cb677c1333a14853b1f0bf46d7fa8c022e9d3