[INFO] updating cached repository https://github.com/u2/leetcode-rust
[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] 23722bdf01b8f3a080af49de576ff52ccbc1c27a
[INFO] testing u2/leetcode-rust against 1.44.0 for beta-1.45-1
[INFO] running `"git" "clone" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fu2%2Fleetcode-rust" "/workspace/builds/worker-2/source"`
[INFO] [stderr] Cloning into '/workspace/builds/worker-2/source'...
[INFO] [stderr] done.
[INFO] validating manifest of git repo https://github.com/u2/leetcode-rust 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/u2/leetcode-rust
[INFO] finished tweaking git repo https://github.com/u2/leetcode-rust
[INFO] tweaked toml for git repo https://github.com/u2/leetcode-rust written to /workspace/builds/worker-2/source/Cargo.toml
[INFO] crate git repo https://github.com/u2/leetcode-rust 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-2/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-2/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] 5d54ceaf70be44ae0bb4c020a2d5390383e786b02c5f56c8c75c651744792697
[INFO] running `"docker" "start" "-a" "5d54ceaf70be44ae0bb4c020a2d5390383e786b02c5f56c8c75c651744792697"`
[INFO] [stderr] sudo: setrlimit(RLIMIT_CORE): Operation not permitted
[INFO] [stderr]    Compiling memchr v1.0.1
[INFO] [stderr]    Compiling thread-id v3.0.0
[INFO] [stderr]    Compiling thread_local v0.3.2
[INFO] [stderr]    Compiling aho-corasick v0.6.1
[INFO] [stderr]    Compiling regex v0.2.1
[INFO] [stderr]    Compiling leetcode v0.1.0 (/opt/rustwide/workdir)
[INFO] [stderr] error[E0554]: `#![feature]` may not be used on the stable release channel
[INFO] [stderr]  --> src/lib.rs:1:1
[INFO] [stderr]   |
[INFO] [stderr] 1 | #![feature(test)]
[INFO] [stderr]   | ^^^^^^^^^^^^^^^^^
[INFO] [stderr] 
[INFO] [stderr] warning: unnecessary parentheses around type
[INFO] [stderr]  --> src/length_of_longest_substring.rs:7:20
[INFO] [stderr]   |
[INFO] [stderr] 7 |     let array: Vec<(char)> = s.char_indices().map(|i| i.1).collect::<Vec<_>>();
[INFO] [stderr]   |                    ^^^^^^ help: remove these parentheses
[INFO] [stderr]   |
[INFO] [stderr]   = note: `#[warn(unused_parens)]` on by default
[INFO] [stderr] 
[INFO] [stderr] warning: unnecessary parentheses around type
[INFO] [stderr]  --> src/length_of_longest_substring.rs:8:25
[INFO] [stderr]   |
[INFO] [stderr] 8 |     let mut c: VecDeque<(char)> = VecDeque::with_capacity(s.char_indices().count());
[INFO] [stderr]   |                         ^^^^^^ help: remove these parentheses
[INFO] [stderr] 
[INFO] [stderr] warning: unnecessary parentheses around type
[INFO] [stderr]   --> src/length_of_longest_substring.rs:39:20
[INFO] [stderr]    |
[INFO] [stderr] 39 |     let array: Vec<(char)> = s.char_indices().map(|i| i.1).collect::<Vec<_>>();
[INFO] [stderr]    |                    ^^^^^^ help: remove these parentheses
[INFO] [stderr] 
[INFO] [stderr] error: aborting due to previous error; 3 warnings emitted
[INFO] [stderr] 
[INFO] [stderr] For more information about this error, try `rustc --explain E0554`.
[INFO] [stderr] error: could not compile `leetcode`.
[INFO] [stderr] 
[INFO] [stderr] To learn more, run the command again with --verbose.
[INFO] [stderr] warning: build failed, waiting for other jobs to finish...
[INFO] [stderr] error: build failed
[INFO] running `"docker" "inspect" "5d54ceaf70be44ae0bb4c020a2d5390383e786b02c5f56c8c75c651744792697"`
[INFO] running `"docker" "rm" "-f" "5d54ceaf70be44ae0bb4c020a2d5390383e786b02c5f56c8c75c651744792697"`
[INFO] [stdout] 5d54ceaf70be44ae0bb4c020a2d5390383e786b02c5f56c8c75c651744792697