[INFO] fetching crate classif 0.0.2...
[INFO] checking classif-0.0.2 against beta for pr-78714
[INFO] extracting crate classif 0.0.2 into /workspace/builds/worker-0/source
[INFO] validating manifest of crates.io crate classif 0.0.2 on toolchain beta
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+beta" "read-manifest" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] started tweaking crates.io crate classif 0.0.2
[INFO] finished tweaking crates.io crate classif 0.0.2
[INFO] tweaked toml for crates.io crate classif 0.0.2 written to /workspace/builds/worker-0/source/Cargo.toml
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+beta" "generate-lockfile" "--manifest-path" "Cargo.toml" "-Zno-index-update", kill_on_drop: false }`
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+beta" "fetch" "--locked" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-0/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-0/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" "rustops/crates-build-env@sha256:6eabd152ff4036248d66efda456a36cb33d24b7291b33f25f75140726c88da35" "/opt/rustwide/cargo-home/bin/cargo" "+beta" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] d29a546c792a818cbf5b17cf1c0024bce02d98115564d96f498531e8e1750c28
[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" "d29a546c792a818cbf5b17cf1c0024bce02d98115564d96f498531e8e1750c28", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "d29a546c792a818cbf5b17cf1c0024bce02d98115564d96f498531e8e1750c28", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "d29a546c792a818cbf5b17cf1c0024bce02d98115564d96f498531e8e1750c28", kill_on_drop: false }`
[INFO] [stdout] d29a546c792a818cbf5b17cf1c0024bce02d98115564d96f498531e8e1750c28
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-0/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-0/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=forbid" "-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" "rustops/crates-build-env@sha256:6eabd152ff4036248d66efda456a36cb33d24b7291b33f25f75140726c88da35" "/opt/rustwide/cargo-home/bin/cargo" "+beta" "check" "--frozen" "--all" "--all-targets" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] c9077aa8e6f3140c5de98129ec51b63dd3e5a14abd24dfc73bff34a8870128ad
[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" "c9077aa8e6f3140c5de98129ec51b63dd3e5a14abd24dfc73bff34a8870128ad", kill_on_drop: false }`
[INFO] [stderr]     Checking classif v0.0.2 (/opt/rustwide/workdir)
[INFO] [stdout] warning: variable does not need to be mutable
[INFO] [stdout]   --> src/jenks.rs:25:13
[INFO] [stdout]    |
[INFO] [stdout] 25 |         let mut v = unsafe { self.values.get_unchecked_mut(ix.0 * self.dim + ix.1) };
[INFO] [stdout]    |             ----^
[INFO] [stdout]    |             |
[INFO] [stdout]    |             help: remove this `mut`
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(unused_mut)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused return value of `collect` that must be used
[INFO] [stdout]  --> src/stats.rs:8:5
[INFO] [stdout]   |
[INFO] [stdout] 8 |     values.iter().map(|v| sum += *v).collect::<Vec<_>>();
[INFO] [stdout]   |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(unused_must_use)]` on by default
[INFO] [stdout]   = note: if you really need to exhaust the iterator, consider `.for_each(drop)` instead
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 2 warnings emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error[E0554]: `#![feature]` may not be used on the beta release channel
[INFO] [stdout]  --> benches/benchmark.rs:1:1
[INFO] [stdout]   |
[INFO] [stdout] 1 | #![feature(test)]
[INFO] [stdout]   | ^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: variable does not need to be mutable
[INFO] [stdout]   --> src/jenks.rs:25:13
[INFO] [stdout]    |
[INFO] [stdout] 25 |         let mut v = unsafe { self.values.get_unchecked_mut(ix.0 * self.dim + ix.1) };
[INFO] [stdout]    |             ----^
[INFO] [stdout]    |             |
[INFO] [stdout]    |             help: remove this `mut`
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(unused_mut)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error: aborting due to previous error
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] For more information about this error, try `rustc --explain E0554`.
[INFO] [stdout] 
[INFO] [stderr] error: could not compile `classif`
[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] [stdout] warning: unused return value of `collect` that must be used
[INFO] [stdout]  --> src/stats.rs:8:5
[INFO] [stdout]   |
[INFO] [stdout] 8 |     values.iter().map(|v| sum += *v).collect::<Vec<_>>();
[INFO] [stdout]   |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(unused_must_use)]` on by default
[INFO] [stdout]   = note: if you really need to exhaust the iterator, consider `.for_each(drop)` instead
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 2 warnings emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr] error: build failed
[INFO] running `Command { std: "docker" "inspect" "c9077aa8e6f3140c5de98129ec51b63dd3e5a14abd24dfc73bff34a8870128ad", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "c9077aa8e6f3140c5de98129ec51b63dd3e5a14abd24dfc73bff34a8870128ad", kill_on_drop: false }`
[INFO] [stdout] c9077aa8e6f3140c5de98129ec51b63dd3e5a14abd24dfc73bff34a8870128ad