[INFO] cloning repository https://github.com/juanibiapina/king
[INFO] running `Command { std: "git" "-c" "credential.helper=" "-c" "credential.helper=/workspace/cargo-home/bin/git-credential-null" "clone" "--bare" "https://github.com/juanibiapina/king" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fjuanibiapina%2Fking", kill_on_drop: false }`
[INFO] [stderr] Cloning into bare repository '/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fjuanibiapina%2Fking'...
[INFO] running `Command { std: "git" "rev-parse" "HEAD", kill_on_drop: false }`
[INFO] [stdout] 1c5a00fcd5ea423eba6579a8a7d7146f9b7e0d55
[INFO] testing juanibiapina/king against 1.55.0 for beta-1.56-1
[INFO] running `Command { std: "git" "clone" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fjuanibiapina%2Fking" "/workspace/builds/worker-1/source", kill_on_drop: false }`
[INFO] [stderr] Cloning into '/workspace/builds/worker-1/source'...
[INFO] [stderr] done.
[INFO] validating manifest of git repo https://github.com/juanibiapina/king on toolchain 1.55.0
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+1.55.0" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }`
[INFO] started tweaking git repo https://github.com/juanibiapina/king
[INFO] finished tweaking git repo https://github.com/juanibiapina/king
[INFO] tweaked toml for git repo https://github.com/juanibiapina/king written to /workspace/builds/worker-1/source/Cargo.toml
[INFO] crate git repo https://github.com/juanibiapina/king already has a lockfile, it will not be regenerated
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+1.55.0" "fetch" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] [stderr]     Blocking waiting for file lock on package cache
[INFO] running `Command { std: "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" "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:a89201d6b5b9fd45c15d5952ece0a0129e7e80cb26ec023fd59cf09bc26f1604" "/opt/rustwide/cargo-home/bin/cargo" "+1.55.0" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stderr] WARNING: Your kernel does not support swap limit capabilities or the cgroup is not mounted. Memory limited without swap.
[INFO] [stdout] 74c8ef7c9830886ac3459abe5b3c076783466177a2074a067bd823b512de4329
[INFO] running `Command { std: "docker" "start" "-a" "74c8ef7c9830886ac3459abe5b3c076783466177a2074a067bd823b512de4329", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "74c8ef7c9830886ac3459abe5b3c076783466177a2074a067bd823b512de4329", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "74c8ef7c9830886ac3459abe5b3c076783466177a2074a067bd823b512de4329", kill_on_drop: false }`
[INFO] [stdout] 74c8ef7c9830886ac3459abe5b3c076783466177a2074a067bd823b512de4329
[INFO] running `Command { std: "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" "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:a89201d6b5b9fd45c15d5952ece0a0129e7e80cb26ec023fd59cf09bc26f1604" "/opt/rustwide/cargo-home/bin/cargo" "+1.55.0" "build" "--frozen" "--message-format=json", kill_on_drop: false }`
[INFO] [stderr] WARNING: Your kernel does not support swap limit capabilities or the cgroup is not mounted. Memory limited without swap.
[INFO] [stdout] 92700e0a4a0b110bf678305f4feebb45a1f54992d7fe51ce61f30fb02bcff9f0
[INFO] running `Command { std: "docker" "start" "-a" "92700e0a4a0b110bf678305f4feebb45a1f54992d7fe51ce61f30fb02bcff9f0", kill_on_drop: false }`
[INFO] [stderr]    Compiling unicode-segmentation v1.2.0
[INFO] [stderr]    Compiling ncurses v5.87.0
[INFO] [stderr]    Compiling king 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(splice)]
[INFO] [stdout]   | ^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unnecessary parentheses around method argument
[INFO] [stdout]   --> src/buffer.rs:45:30
[INFO] [stdout]    |
[INFO] [stdout] 45 |         self.contents.insert((y + 1), rest);
[INFO] [stdout]    |                              ^^^^^^^ help: remove these parentheses
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(unused_parens)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error[E0599]: no method named `splice` found for struct `String` in the current scope
[INFO] [stdout]   --> src/buffer.rs:79:34
[INFO] [stdout]    |
[INFO] [stdout] 79 |                 self.contents[y].splice(offset..(offset+grapheme.len()), "");
[INFO] [stdout]    |                                  ^^^^^^ help: there is an associated function with a similar name: `split`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error: aborting due to 2 previous errors; 1 warning emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] Some errors have detailed explanations: E0554, E0599.
[INFO] [stdout] 
[INFO] [stdout] For more information about an error, try `rustc --explain E0554`.
[INFO] [stdout] 
[INFO] [stderr] error: could not compile `king` due to 3 previous errors; 1 warning emitted
[INFO] running `Command { std: "docker" "inspect" "92700e0a4a0b110bf678305f4feebb45a1f54992d7fe51ce61f30fb02bcff9f0", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "92700e0a4a0b110bf678305f4feebb45a1f54992d7fe51ce61f30fb02bcff9f0", kill_on_drop: false }`
[INFO] [stdout] 92700e0a4a0b110bf678305f4feebb45a1f54992d7fe51ce61f30fb02bcff9f0