[INFO] fetching crate kannon 0.0.2...
[INFO] testing kannon-0.0.2 against beta-2021-08-01 for beta-1.55-1
[INFO] extracting crate kannon 0.0.2 into /workspace/builds/worker-4/source
[INFO] validating manifest of crates.io crate kannon 0.0.2 on toolchain beta-2021-08-01
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+beta-2021-08-01" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }`
[INFO] started tweaking crates.io crate kannon 0.0.2
[INFO] finished tweaking crates.io crate kannon 0.0.2
[INFO] tweaked toml for crates.io crate kannon 0.0.2 written to /workspace/builds/worker-4/source/Cargo.toml
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+beta-2021-08-01" "generate-lockfile" "--manifest-path" "Cargo.toml" "-Zno-index-update", kill_on_drop: false }`
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+beta-2021-08-01" "fetch" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] [stderr] warning: `panic` setting is ignored for `test` profile
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-4/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-4/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" "+beta-2021-08-01" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] 5c03e7fbb709887890bcf5dca5271ad72c1f5edfc500fe920701c168426e51a2
[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" "5c03e7fbb709887890bcf5dca5271ad72c1f5edfc500fe920701c168426e51a2", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "5c03e7fbb709887890bcf5dca5271ad72c1f5edfc500fe920701c168426e51a2", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "5c03e7fbb709887890bcf5dca5271ad72c1f5edfc500fe920701c168426e51a2", kill_on_drop: false }`
[INFO] [stdout] 5c03e7fbb709887890bcf5dca5271ad72c1f5edfc500fe920701c168426e51a2
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-4/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-4/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" "+beta-2021-08-01" "build" "--frozen" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] 106ab58a3ab42e2aeeccc7dd96544c4b8edd36fb05139013a3cb2c5e3b857182
[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" "106ab58a3ab42e2aeeccc7dd96544c4b8edd36fb05139013a3cb2c5e3b857182", kill_on_drop: false }`
[INFO] [stderr] warning: `panic` setting is ignored for `test` profile
[INFO] [stderr]    Compiling kannon v0.0.2 (/opt/rustwide/workdir)
[INFO] [stdout] error[E0554]: `#![feature]` may not be used on the beta release channel
[INFO] [stdout]  --> src/lib.rs:2:1
[INFO] [stdout]   |
[INFO] [stdout] 2 | #![feature(allocator_api)]
[INFO] [stdout]   | ^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error[E0554]: `#![feature]` may not be used on the beta release channel
[INFO] [stdout]  --> src/lib.rs:3:1
[INFO] [stdout]   |
[INFO] [stdout] 3 | #![feature(available_concurrency)]
[INFO] [stdout]   | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unreachable statement
[INFO] [stdout]    --> src/task/group.rs:404:9
[INFO] [stdout]     |
[INFO] [stdout] 403 |           todo!("Not yet implemented");
[INFO] [stdout]     |           ----------------------------- any code following this expression is unreachable
[INFO] [stdout] 404 | /         let pred: &dyn Fn(&&GroupHandle) -> bool = &|x: &&GroupHandle| match (*x).value_as_ref() {
[INFO] [stdout] 405 | |             None => false,
[INFO] [stdout] 406 | |             Some(accessor) => accessor.has_predecessors(),
[INFO] [stdout] 407 | |         };
[INFO] [stdout]     | |__________^ unreachable statement
[INFO] [stdout]     |
[INFO] [stdout]     = note: `#[warn(unreachable_code)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error: aborting due to 2 previous errors; 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 `kannon` due to 3 previous errors; 1 warning emitted
[INFO] running `Command { std: "docker" "inspect" "106ab58a3ab42e2aeeccc7dd96544c4b8edd36fb05139013a3cb2c5e3b857182", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "106ab58a3ab42e2aeeccc7dd96544c4b8edd36fb05139013a3cb2c5e3b857182", kill_on_drop: false }`
[INFO] [stdout] 106ab58a3ab42e2aeeccc7dd96544c4b8edd36fb05139013a3cb2c5e3b857182
