[INFO] cloning repository https://github.com/DhruvDh/advection
[INFO] running `Command { std: "git" "-c" "credential.helper=" "-c" "credential.helper=/workspace/cargo-home/bin/git-credential-null" "clone" "--bare" "https://github.com/DhruvDh/advection" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2FDhruvDh%2Fadvection", kill_on_drop: false }`
[INFO] [stderr] Cloning into bare repository '/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2FDhruvDh%2Fadvection'...
[INFO] running `Command { std: "git" "rev-parse" "HEAD", kill_on_drop: false }`
[INFO] [stdout] 47d3536f65b72261ab6e435ec80a519570a08c43
[INFO] testing DhruvDh/advection against 1.54.0 for beta-1.55-1
[INFO] running `Command { std: "git" "clone" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2FDhruvDh%2Fadvection" "/workspace/builds/worker-7/source", kill_on_drop: false }`
[INFO] [stderr] Cloning into '/workspace/builds/worker-7/source'...
[INFO] [stderr] done.
[INFO] validating manifest of git repo https://github.com/DhruvDh/advection 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/DhruvDh/advection
[INFO] finished tweaking git repo https://github.com/DhruvDh/advection
[INFO] tweaked toml for git repo https://github.com/DhruvDh/advection written to /workspace/builds/worker-7/source/Cargo.toml
[INFO] crate git repo https://github.com/DhruvDh/advection 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] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-7/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-7/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] f65145b6af8a5b5622c37b8c4f63f9b4b142d46719c1cf3f17c55d9761ff1fce
[INFO] [stderr] WARNING: Your kernel does not support swap limit capabilities or the cgroup is not mounted. Memory limited without swap.
[INFO] running `Command { std: "docker" "start" "-a" "f65145b6af8a5b5622c37b8c4f63f9b4b142d46719c1cf3f17c55d9761ff1fce", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "f65145b6af8a5b5622c37b8c4f63f9b4b142d46719c1cf3f17c55d9761ff1fce", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "f65145b6af8a5b5622c37b8c4f63f9b4b142d46719c1cf3f17c55d9761ff1fce", kill_on_drop: false }`
[INFO] [stdout] f65145b6af8a5b5622c37b8c4f63f9b4b142d46719c1cf3f17c55d9761ff1fce
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-7/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-7/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] [stderr] WARNING: Your kernel does not support swap limit capabilities or the cgroup is not mounted. Memory limited without swap.
[INFO] [stdout] 8a38ed12d6eefceb67c13cc5ae76dc49066c215b4b49b52aeffb6cba81ad1607
[INFO] running `Command { std: "docker" "start" "-a" "8a38ed12d6eefceb67c13cc5ae76dc49066c215b4b49b52aeffb6cba81ad1607", kill_on_drop: false }`
[INFO] [stderr]    Compiling advection v0.1.0 (/opt/rustwide/workdir)
[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(non_ascii_idents)]
[INFO] [stdout]   | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: remove the attribute
[INFO] [stdout]   |
[INFO] [stdout]   = help: the feature `non_ascii_idents` has been stable since 1.53.0 and no longer requires an attribute to enable
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: The usage of Script Group `Greek` in this crate consists solely of mixed script confusables
[INFO] [stdout]   --> src/main.rs:18:9
[INFO] [stdout]    |
[INFO] [stdout] 18 |     let α = v * dt/(2.0 * dx);
[INFO] [stdout]    |         ^
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(mixed_script_confusables)]` on by default
[INFO] [stdout]    = note: The usage includes 'α' (U+03B1).
[INFO] [stdout]    = note: Please recheck to make sure their usages are indeed what you want.
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error: aborting due to previous error; 1 warning 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 `advection`
[INFO] [stderr] 
[INFO] [stderr] To learn more, run the command again with --verbose.
[INFO] running `Command { std: "docker" "inspect" "8a38ed12d6eefceb67c13cc5ae76dc49066c215b4b49b52aeffb6cba81ad1607", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "8a38ed12d6eefceb67c13cc5ae76dc49066c215b4b49b52aeffb6cba81ad1607", kill_on_drop: false }`
[INFO] [stdout] 8a38ed12d6eefceb67c13cc5ae76dc49066c215b4b49b52aeffb6cba81ad1607