[INFO] cloning repository https://github.com/u2/leetcode-rust
[INFO] running `Command { std: "git" "-c" "credential.helper=" "-c" "credential.helper=/workspace/cargo-home/bin/git-credential-null" "clone" "--bare" "https://github.com/u2/leetcode-rust" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fu2%2Fleetcode-rust", kill_on_drop: false }`
[INFO] [stderr] Cloning into bare repository '/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fu2%2Fleetcode-rust'...
[INFO] running `Command { std: "git" "rev-parse" "HEAD", kill_on_drop: false }`
[INFO] [stdout] 23722bdf01b8f3a080af49de576ff52ccbc1c27a
[INFO] testing u2/leetcode-rust against 1.54.0 for beta-1.55-1
[INFO] running `Command { std: "git" "clone" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fu2%2Fleetcode-rust" "/workspace/builds/worker-86/source", kill_on_drop: false }`
[INFO] [stderr] Cloning into '/workspace/builds/worker-86/source'...
[INFO] [stderr] done.
[INFO] validating manifest of git repo https://github.com/u2/leetcode-rust on toolchain 1.54.0
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+1.54.0" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }`
[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-86/source/Cargo.toml
[INFO] crate git repo https://github.com/u2/leetcode-rust already has a lockfile, it will not be regenerated
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+1.54.0" "fetch" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] [stderr]     Blocking waiting for file lock on package cache
[INFO] [stderr]  Downloading crates ...
[INFO] [stderr]   Downloaded thread_local v0.3.2
[INFO] [stderr]   Downloaded aho-corasick v0.6.1
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-86/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-86/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" "CARGO_TARGET_DIR=/opt/rustwide/target" "-e" "CARGO_HOME=/opt/rustwide/cargo-home" "-e" "RUSTUP_HOME=/opt/rustwide/rustup-home" "-w" "/opt/rustwide/workdir" "-m" "1610612736" "--user" "0:0" "--network" "none" "ghcr.io/rust-lang/crates-build-env/linux@sha256:34b6a614d2c27851fe6cbf88fbd1137609cefab8b10d0615aaeb6fd47975d74e" "/opt/rustwide/cargo-home/bin/cargo" "+1.54.0" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] 5cc5c831cc1555157b0469f007ad575468878ff5ecf173d4b1fc6cd4026ea0df
[INFO] running `Command { std: "docker" "start" "-a" "5cc5c831cc1555157b0469f007ad575468878ff5ecf173d4b1fc6cd4026ea0df", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "5cc5c831cc1555157b0469f007ad575468878ff5ecf173d4b1fc6cd4026ea0df", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "5cc5c831cc1555157b0469f007ad575468878ff5ecf173d4b1fc6cd4026ea0df", kill_on_drop: false }`
[INFO] [stdout] 5cc5c831cc1555157b0469f007ad575468878ff5ecf173d4b1fc6cd4026ea0df
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-86/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-86/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" "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" "--user" "0:0" "--network" "none" "ghcr.io/rust-lang/crates-build-env/linux@sha256:34b6a614d2c27851fe6cbf88fbd1137609cefab8b10d0615aaeb6fd47975d74e" "/opt/rustwide/cargo-home/bin/cargo" "+1.54.0" "build" "--frozen" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] 74f80d5b1a9b660b2c67d55742f9618804641976c32ddb35e45e6bf71d4edf8a
[INFO] running `Command { std: "docker" "start" "-a" "74f80d5b1a9b660b2c67d55742f9618804641976c32ddb35e45e6bf71d4edf8a", kill_on_drop: false }`
[INFO] [stderr]     Blocking waiting for file lock on package cache
[INFO] [stderr]    Compiling libc v0.2.20
[INFO] [stderr]    Compiling regex-syntax v0.4.0
[INFO] [stderr]    Compiling unreachable v0.1.1
[INFO] [stderr]    Compiling thread-id v3.0.0
[INFO] [stderr]    Compiling memchr v1.0.1
[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] [stdout] error[E0554]: `#![feature]` may not be used on the stable release channel
[INFO] [stdout]  --> src/lib.rs:1:1
[INFO] [stdout]   |
[INFO] [stdout] 1 | #![feature(test)]
[INFO] [stdout]   | ^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unnecessary parentheses around type
[INFO] [stdout]  --> src/length_of_longest_substring.rs:7:20
[INFO] [stdout]   |
[INFO] [stdout] 7 |     let array: Vec<(char)> = s.char_indices().map(|i| i.1).collect::<Vec<_>>();
[INFO] [stdout]   |                    ^^^^^^ help: remove these parentheses
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(unused_parens)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unnecessary parentheses around type
[INFO] [stdout]  --> src/length_of_longest_substring.rs:8:25
[INFO] [stdout]   |
[INFO] [stdout] 8 |     let mut c: VecDeque<(char)> = VecDeque::with_capacity(s.char_indices().count());
[INFO] [stdout]   |                         ^^^^^^ help: remove these parentheses
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unnecessary parentheses around type
[INFO] [stdout]   --> src/length_of_longest_substring.rs:39:20
[INFO] [stdout]    |
[INFO] [stdout] 39 |     let array: Vec<(char)> = s.char_indices().map(|i| i.1).collect::<Vec<_>>();
[INFO] [stdout]    |                    ^^^^^^ help: remove these parentheses
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error: aborting due to previous error; 3 warnings emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] For more information about this error, try `rustc --explain E0554`.
[INFO] [stdout] 
[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 `Command { std: "docker" "inspect" "74f80d5b1a9b660b2c67d55742f9618804641976c32ddb35e45e6bf71d4edf8a", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "74f80d5b1a9b660b2c67d55742f9618804641976c32ddb35e45e6bf71d4edf8a", kill_on_drop: false }`
[INFO] [stdout] 74f80d5b1a9b660b2c67d55742f9618804641976c32ddb35e45e6bf71d4edf8a
