[INFO] cloning repository https://github.com/ntBre/checkplus
[INFO] running `Command { std: "git" "-c" "credential.helper=" "-c" "credential.helper=/workspace/cargo-home/bin/git-credential-null" "clone" "--bare" "https://github.com/ntBre/checkplus" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2FntBre%2Fcheckplus", kill_on_drop: false }`
[INFO] [stderr] Cloning into bare repository '/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2FntBre%2Fcheckplus'...
[INFO] running `Command { std: "git" "rev-parse" "HEAD", kill_on_drop: false }`
[INFO] [stdout] ab8bf626695e5130ef2050d82c84ed1cc76153db
[INFO] testing ntBre/checkplus against 1.91.0 for beta-1.92-2
[INFO] running `Command { std: "git" "clone" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2FntBre%2Fcheckplus" "/workspace/builds/worker-0-tc1/source", kill_on_drop: false }`
[INFO] [stderr] Cloning into '/workspace/builds/worker-0-tc1/source'...
[INFO] [stderr] done.
[INFO] started tweaking git repo https://github.com/ntBre/checkplus
[INFO] finished tweaking git repo https://github.com/ntBre/checkplus
[INFO] tweaked toml for git repo https://github.com/ntBre/checkplus written to /workspace/builds/worker-0-tc1/source/Cargo.toml
[INFO] validating manifest of git repo https://github.com/ntBre/checkplus on toolchain 1.91.0
[INFO] running `Command { std: CARGO_HOME="/workspace/cargo-home" RUSTUP_HOME="/workspace/rustup-home" "/workspace/cargo-home/bin/cargo" "+1.91.0" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }`
[INFO] crate git repo https://github.com/ntBre/checkplus already has a lockfile, it will not be regenerated
[INFO] running `Command { std: CARGO_HOME="/workspace/cargo-home" RUSTUP_HOME="/workspace/rustup-home" "/workspace/cargo-home/bin/cargo" "+1.91.0" "fetch" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
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[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-0-tc1/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-0-tc1/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@sha256:4848fb76d95f26979359cc7e45710b1dbc8f3acb7aeedee7c460d7702230f228" "/opt/rustwide/cargo-home/bin/cargo" "+1.91.0" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] 6b5a7e3fb87644103f58a9827b1852899351198bfc48497420b62c8cf5ffed15
[INFO] running `Command { std: "docker" "start" "-a" "6b5a7e3fb87644103f58a9827b1852899351198bfc48497420b62c8cf5ffed15", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "6b5a7e3fb87644103f58a9827b1852899351198bfc48497420b62c8cf5ffed15", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "6b5a7e3fb87644103f58a9827b1852899351198bfc48497420b62c8cf5ffed15", kill_on_drop: false }`
[INFO] [stdout] 6b5a7e3fb87644103f58a9827b1852899351198bfc48497420b62c8cf5ffed15
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-0-tc1/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-0-tc1/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" "RUSTDOCFLAGS=--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@sha256:4848fb76d95f26979359cc7e45710b1dbc8f3acb7aeedee7c460d7702230f228" "/opt/rustwide/cargo-home/bin/cargo" "+1.91.0" "build" "--frozen" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] 9c7d5bb8213060a7dd461ef08225b81adb7cd47d3b74bca6e36a92e09e14fef3
[INFO] running `Command { std: "docker" "start" "-a" "9c7d5bb8213060a7dd461ef08225b81adb7cd47d3b74bca6e36a92e09e14fef3", kill_on_drop: false }`
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[INFO] [stderr]    Compiling sctk-adwaita v0.5.4
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[INFO] [stderr]    Compiling checkplus v0.1.0 (/opt/rustwide/workdir)
[INFO] [stdout] error: let chains are only allowed in Rust 2024 or later
[INFO] [stdout]    --> src/board.rs:237:28
[INFO] [stdout]     |
[INFO] [stdout] 237 |                         if let Some(fr) = from_rank && *fr != rank {
[INFO] [stdout]     |                            ^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error: let chains are only allowed in Rust 2024 or later
[INFO] [stdout]    --> src/board.rs:240:28
[INFO] [stdout]     |
[INFO] [stdout] 240 |                         if let Some(ff) = from_file && *ff != file {
[INFO] [stdout]     |                            ^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error[E0554]: `#![feature]` may not be used on the stable release channel
[INFO] [stdout]  --> src/main.rs:1:1
[INFO] [stdout]   |
[INFO] [stdout] 1 | #![feature(iter_array_chunks, array_chunks, let_chains, lazy_cell)]
[INFO] [stdout]   | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout]   |
[INFO] [stdout]   = help: the feature `let_chains` has been stable since `1.88.0` and no longer requires an attribute to enable
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: the feature `let_chains` has been stable since 1.88.0 and no longer requires an attribute to enable
[INFO] [stdout]  --> src/main.rs:1:45
[INFO] [stdout]   |
[INFO] [stdout] 1 | #![feature(iter_array_chunks, array_chunks, let_chains, lazy_cell)]
[INFO] [stdout]   |                                             ^^^^^^^^^^
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(stable_features)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: the feature `lazy_cell` has been stable since 1.80.0 and no longer requires an attribute to enable
[INFO] [stdout]  --> src/main.rs:1:57
[INFO] [stdout]   |
[INFO] [stdout] 1 | #![feature(iter_array_chunks, array_chunks, let_chains, lazy_cell)]
[INFO] [stdout]   |                                                         ^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error[E0635]: unknown feature `array_chunks`
[INFO] [stdout]  --> src/main.rs:1:31
[INFO] [stdout]   |
[INFO] [stdout] 1 | #![feature(iter_array_chunks, array_chunks, let_chains, lazy_cell)]
[INFO] [stdout]   |                               ^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] Some errors have detailed explanations: E0554, E0635.
[INFO] [stdout] 
[INFO] [stdout] For more information about an error, try `rustc --explain E0554`.
[INFO] [stdout] 
[INFO] [stderr] error: could not compile `checkplus` (bin "checkplus") due to 4 previous errors; 2 warnings emitted
[INFO] running `Command { std: "docker" "inspect" "9c7d5bb8213060a7dd461ef08225b81adb7cd47d3b74bca6e36a92e09e14fef3", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "9c7d5bb8213060a7dd461ef08225b81adb7cd47d3b74bca6e36a92e09e14fef3", kill_on_drop: false }`
[INFO] [stdout] 9c7d5bb8213060a7dd461ef08225b81adb7cd47d3b74bca6e36a92e09e14fef3