[INFO] fetching crate juggernaut 0.9.0...
[INFO] checking juggernaut-0.9.0 against 1.55.0 for beta-1.56-3
[INFO] extracting crate juggernaut 0.9.0 into /workspace/builds/worker-81/source
[INFO] validating manifest of crates.io crate juggernaut 0.9.0 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 crates.io crate juggernaut 0.9.0
[INFO] finished tweaking crates.io crate juggernaut 0.9.0
[INFO] tweaked toml for crates.io crate juggernaut 0.9.0 written to /workspace/builds/worker-81/source/Cargo.toml
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+1.55.0" "generate-lockfile" "--manifest-path" "Cargo.toml" "-Zno-index-update", kill_on_drop: false }`
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+1.55.0" "fetch" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-81/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-81/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] [stdout] f61cfda462bbb5df671fa22a7c8b585e140fb2d7cd0cc3e0c512aa65a24c2b48
[INFO] running `Command { std: "docker" "start" "-a" "f61cfda462bbb5df671fa22a7c8b585e140fb2d7cd0cc3e0c512aa65a24c2b48", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "f61cfda462bbb5df671fa22a7c8b585e140fb2d7cd0cc3e0c512aa65a24c2b48", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "f61cfda462bbb5df671fa22a7c8b585e140fb2d7cd0cc3e0c512aa65a24c2b48", kill_on_drop: false }`
[INFO] [stdout] f61cfda462bbb5df671fa22a7c8b585e140fb2d7cd0cc3e0c512aa65a24c2b48
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-81/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-81/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" "check" "--frozen" "--all" "--all-targets" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] 1f64edf91f8ff728a686d8a472ceb7498a75f2d01d157e909724156f8fc45466
[INFO] running `Command { std: "docker" "start" "-a" "1f64edf91f8ff728a686d8a472ceb7498a75f2d01d157e909724156f8fc45466", kill_on_drop: false }`
[INFO] [stderr]     Checking assert_approx_eq v1.1.0
[INFO] [stderr]     Checking rand v0.3.23
[INFO] [stderr]     Checking juggernaut v0.9.0 (/opt/rustwide/workdir)
[INFO] [stdout] warning: unused `#[macro_use]` import
[INFO] [stdout]  --> src/lib.rs:1:1
[INFO] [stdout]   |
[INFO] [stdout] 1 | #[macro_use]
[INFO] [stdout]   | ^^^^^^^^^^^^
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(unused_imports)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: trait objects without an explicit `dyn` are deprecated
[INFO] [stdout]   --> src/matrix.rs:13:41
[INFO] [stdout]    |
[INFO] [stdout] 13 |     fn generate(m: usize, n: usize, f: &Fn(usize, usize) -> f64) -> Self;
[INFO] [stdout]    |                                         ^^^^^^^^^^^^^^^^^^^^^^^ help: use `dyn`: `dyn Fn(usize, usize) -> f64`
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(bare_trait_objects)]` on by default
[INFO] [stdout]    = warning: this is accepted in the current edition (Rust 2015) but is a hard error in Rust 2021!
[INFO] [stdout]    = note: for more information, see issue #80165 <https://github.com/rust-lang/rust/issues/80165>
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: trait objects without an explicit `dyn` are deprecated
[INFO] [stdout]   --> src/matrix.rs:14:48
[INFO] [stdout]    |
[INFO] [stdout] 14 |     fn generate_by_row(m: usize, n: usize, f: &Fn(usize) -> Vec<f64>) -> Self;
[INFO] [stdout]    |                                                ^^^^^^^^^^^^^^^^^^^^^ help: use `dyn`: `dyn Fn(usize) -> Vec<f64>`
[INFO] [stdout]    |
[INFO] [stdout]    = warning: this is accepted in the current edition (Rust 2015) but is a hard error in Rust 2021!
[INFO] [stdout]    = note: for more information, see issue #80165 <https://github.com/rust-lang/rust/issues/80165>
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: trait objects without an explicit `dyn` are deprecated
[INFO] [stdout]   --> src/matrix.rs:21:23
[INFO] [stdout]    |
[INFO] [stdout] 21 |     fn map(&self, f: &Fn(f64, usize, usize) -> f64) -> Matrix;
[INFO] [stdout]    |                       ^^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: use `dyn`: `dyn Fn(f64, usize, usize) -> f64`
[INFO] [stdout]    |
[INFO] [stdout]    = warning: this is accepted in the current edition (Rust 2015) but is a hard error in Rust 2021!
[INFO] [stdout]    = note: for more information, see issue #80165 <https://github.com/rust-lang/rust/issues/80165>
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: trait objects without an explicit `dyn` are deprecated
[INFO] [stdout]   --> src/matrix.rs:22:27
[INFO] [stdout]    |
[INFO] [stdout] 22 |     fn map_row(&self, f: &Fn(Vec<f64>) -> Vec<f64>) -> Matrix;
[INFO] [stdout]    |                           ^^^^^^^^^^^^^^^^^^^^^^^^ help: use `dyn`: `dyn Fn(Vec<f64>) -> Vec<f64>`
[INFO] [stdout]    |
[INFO] [stdout]    = warning: this is accepted in the current edition (Rust 2015) but is a hard error in Rust 2021!
[INFO] [stdout]    = note: for more information, see issue #80165 <https://github.com/rust-lang/rust/issues/80165>
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: trait objects without an explicit `dyn` are deprecated
[INFO] [stdout]   --> src/matrix.rs:40:41
[INFO] [stdout]    |
[INFO] [stdout] 40 |     fn generate(m: usize, n: usize, f: &Fn(usize, usize) -> f64) -> Matrix {
[INFO] [stdout]    |                                         ^^^^^^^^^^^^^^^^^^^^^^^ help: use `dyn`: `dyn Fn(usize, usize) -> f64`
[INFO] [stdout]    |
[INFO] [stdout]    = warning: this is accepted in the current edition (Rust 2015) but is a hard error in Rust 2021!
[INFO] [stdout]    = note: for more information, see issue #80165 <https://github.com/rust-lang/rust/issues/80165>
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: trait objects without an explicit `dyn` are deprecated
[INFO] [stdout]   --> src/matrix.rs:60:48
[INFO] [stdout]    |
[INFO] [stdout] 60 |     fn generate_by_row(m: usize, n: usize, f: &Fn(usize) -> Vec<f64>) -> Matrix {
[INFO] [stdout]    |                                                ^^^^^^^^^^^^^^^^^^^^^ help: use `dyn`: `dyn Fn(usize) -> Vec<f64>`
[INFO] [stdout]    |
[INFO] [stdout]    = warning: this is accepted in the current edition (Rust 2015) but is a hard error in Rust 2021!
[INFO] [stdout]    = note: for more information, see issue #80165 <https://github.com/rust-lang/rust/issues/80165>
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: trait objects without an explicit `dyn` are deprecated
[INFO] [stdout]    --> src/matrix.rs:145:23
[INFO] [stdout]     |
[INFO] [stdout] 145 |     fn map(&self, f: &Fn(f64, usize, usize) -> f64) -> Matrix {
[INFO] [stdout]     |                       ^^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: use `dyn`: `dyn Fn(f64, usize, usize) -> f64`
[INFO] [stdout]     |
[INFO] [stdout]     = warning: this is accepted in the current edition (Rust 2015) but is a hard error in Rust 2021!
[INFO] [stdout]     = note: for more information, see issue #80165 <https://github.com/rust-lang/rust/issues/80165>
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: trait objects without an explicit `dyn` are deprecated
[INFO] [stdout]    --> src/matrix.rs:150:27
[INFO] [stdout]     |
[INFO] [stdout] 150 |     fn map_row(&self, f: &Fn(Vec<f64>) -> Vec<f64>) -> Matrix {
[INFO] [stdout]     |                           ^^^^^^^^^^^^^^^^^^^^^^^^ help: use `dyn`: `dyn Fn(Vec<f64>) -> Vec<f64>`
[INFO] [stdout]     |
[INFO] [stdout]     = warning: this is accepted in the current edition (Rust 2015) but is a hard error in Rust 2021!
[INFO] [stdout]     = note: for more information, see issue #80165 <https://github.com/rust-lang/rust/issues/80165>
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: trait objects without an explicit `dyn` are deprecated
[INFO] [stdout]  --> src/nl.rs:7:25
[INFO] [stdout]   |
[INFO] [stdout] 7 |     pub activation: Box<Activation>,
[INFO] [stdout]   |                         ^^^^^^^^^^ help: use `dyn`: `dyn Activation`
[INFO] [stdout]   |
[INFO] [stdout]   = warning: this is accepted in the current edition (Rust 2015) but is a hard error in Rust 2021!
[INFO] [stdout]   = note: for more information, see issue #80165 <https://github.com/rust-lang/rust/issues/80165>
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: trait objects without an explicit `dyn` are deprecated
[INFO] [stdout]   --> src/nn.rs:15:24
[INFO] [stdout]    |
[INFO] [stdout] 15 |     cost_function: Box<CostFunction>,
[INFO] [stdout]    |                        ^^^^^^^^^^^^ help: use `dyn`: `dyn CostFunction`
[INFO] [stdout]    |
[INFO] [stdout]    = warning: this is accepted in the current edition (Rust 2015) but is a hard error in Rust 2021!
[INFO] [stdout]    = note: for more information, see issue #80165 <https://github.com/rust-lang/rust/issues/80165>
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: trait objects without an explicit `dyn` are deprecated
[INFO] [stdout]   --> src/nn.rs:17:29
[INFO] [stdout]    |
[INFO] [stdout] 17 |     on_error_fn: Option<Box<Fn(f64)>>,
[INFO] [stdout]    |                             ^^^^^^^ help: use `dyn`: `dyn Fn(f64)`
[INFO] [stdout]    |
[INFO] [stdout]    = warning: this is accepted in the current edition (Rust 2015) but is a hard error in Rust 2021!
[INFO] [stdout]    = note: for more information, see issue #80165 <https://github.com/rust-lang/rust/issues/80165>
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: trait objects without an explicit `dyn` are deprecated
[INFO] [stdout]   --> src/nn.rs:18:29
[INFO] [stdout]    |
[INFO] [stdout] 18 |     on_epoch_fn: Option<Box<Fn(&NeuralNetwork)>>,
[INFO] [stdout]    |                             ^^^^^^^^^^^^^^^^^^ help: use `dyn`: `dyn Fn(&NeuralNetwork)`
[INFO] [stdout]    |
[INFO] [stdout]    = warning: this is accepted in the current edition (Rust 2015) but is a hard error in Rust 2021!
[INFO] [stdout]    = note: for more information, see issue #80165 <https://github.com/rust-lang/rust/issues/80165>
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unnecessary parentheses around block return value
[INFO] [stdout]   --> src/cost/cross_entropy.rs:60:9
[INFO] [stdout]    |
[INFO] [stdout] 60 |         (cost.fold(0f64, |sum, val| sum + val) / target.cols() as f64)
[INFO] [stdout]    |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: remove these parentheses
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(unused_parens)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: trait objects without an explicit `dyn` are deprecated
[INFO] [stdout]   --> src/matrix.rs:13:41
[INFO] [stdout]    |
[INFO] [stdout] 13 |     fn generate(m: usize, n: usize, f: &Fn(usize, usize) -> f64) -> Self;
[INFO] [stdout]    |                                         ^^^^^^^^^^^^^^^^^^^^^^^ help: use `dyn`: `dyn Fn(usize, usize) -> f64`
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(bare_trait_objects)]` on by default
[INFO] [stdout]    = warning: this is accepted in the current edition (Rust 2015) but is a hard error in Rust 2021!
[INFO] [stdout]    = note: for more information, see issue #80165 <https://github.com/rust-lang/rust/issues/80165>
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: trait objects without an explicit `dyn` are deprecated
[INFO] [stdout]   --> src/matrix.rs:14:48
[INFO] [stdout]    |
[INFO] [stdout] 14 |     fn generate_by_row(m: usize, n: usize, f: &Fn(usize) -> Vec<f64>) -> Self;
[INFO] [stdout]    |                                                ^^^^^^^^^^^^^^^^^^^^^ help: use `dyn`: `dyn Fn(usize) -> Vec<f64>`
[INFO] [stdout]    |
[INFO] [stdout]    = warning: this is accepted in the current edition (Rust 2015) but is a hard error in Rust 2021!
[INFO] [stdout]    = note: for more information, see issue #80165 <https://github.com/rust-lang/rust/issues/80165>
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: trait objects without an explicit `dyn` are deprecated
[INFO] [stdout]   --> src/matrix.rs:21:23
[INFO] [stdout]    |
[INFO] [stdout] 21 |     fn map(&self, f: &Fn(f64, usize, usize) -> f64) -> Matrix;
[INFO] [stdout]    |                       ^^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: use `dyn`: `dyn Fn(f64, usize, usize) -> f64`
[INFO] [stdout]    |
[INFO] [stdout]    = warning: this is accepted in the current edition (Rust 2015) but is a hard error in Rust 2021!
[INFO] [stdout]    = note: for more information, see issue #80165 <https://github.com/rust-lang/rust/issues/80165>
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: trait objects without an explicit `dyn` are deprecated
[INFO] [stdout]   --> src/matrix.rs:22:27
[INFO] [stdout]    |
[INFO] [stdout] 22 |     fn map_row(&self, f: &Fn(Vec<f64>) -> Vec<f64>) -> Matrix;
[INFO] [stdout]    |                           ^^^^^^^^^^^^^^^^^^^^^^^^ help: use `dyn`: `dyn Fn(Vec<f64>) -> Vec<f64>`
[INFO] [stdout]    |
[INFO] [stdout]    = warning: this is accepted in the current edition (Rust 2015) but is a hard error in Rust 2021!
[INFO] [stdout]    = note: for more information, see issue #80165 <https://github.com/rust-lang/rust/issues/80165>
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: trait objects without an explicit `dyn` are deprecated
[INFO] [stdout]   --> src/matrix.rs:40:41
[INFO] [stdout]    |
[INFO] [stdout] 40 |     fn generate(m: usize, n: usize, f: &Fn(usize, usize) -> f64) -> Matrix {
[INFO] [stdout]    |                                         ^^^^^^^^^^^^^^^^^^^^^^^ help: use `dyn`: `dyn Fn(usize, usize) -> f64`
[INFO] [stdout]    |
[INFO] [stdout]    = warning: this is accepted in the current edition (Rust 2015) but is a hard error in Rust 2021!
[INFO] [stdout]    = note: for more information, see issue #80165 <https://github.com/rust-lang/rust/issues/80165>
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: trait objects without an explicit `dyn` are deprecated
[INFO] [stdout]   --> src/matrix.rs:60:48
[INFO] [stdout]    |
[INFO] [stdout] 60 |     fn generate_by_row(m: usize, n: usize, f: &Fn(usize) -> Vec<f64>) -> Matrix {
[INFO] [stdout]    |                                                ^^^^^^^^^^^^^^^^^^^^^ help: use `dyn`: `dyn Fn(usize) -> Vec<f64>`
[INFO] [stdout]    |
[INFO] [stdout]    = warning: this is accepted in the current edition (Rust 2015) but is a hard error in Rust 2021!
[INFO] [stdout]    = note: for more information, see issue #80165 <https://github.com/rust-lang/rust/issues/80165>
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: trait objects without an explicit `dyn` are deprecated
[INFO] [stdout]    --> src/matrix.rs:145:23
[INFO] [stdout]     |
[INFO] [stdout] 145 |     fn map(&self, f: &Fn(f64, usize, usize) -> f64) -> Matrix {
[INFO] [stdout]     |                       ^^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: use `dyn`: `dyn Fn(f64, usize, usize) -> f64`
[INFO] [stdout]     |
[INFO] [stdout]     = warning: this is accepted in the current edition (Rust 2015) but is a hard error in Rust 2021!
[INFO] [stdout]     = note: for more information, see issue #80165 <https://github.com/rust-lang/rust/issues/80165>
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: trait objects without an explicit `dyn` are deprecated
[INFO] [stdout]    --> src/matrix.rs:150:27
[INFO] [stdout]     |
[INFO] [stdout] 150 |     fn map_row(&self, f: &Fn(Vec<f64>) -> Vec<f64>) -> Matrix {
[INFO] [stdout]     |                           ^^^^^^^^^^^^^^^^^^^^^^^^ help: use `dyn`: `dyn Fn(Vec<f64>) -> Vec<f64>`
[INFO] [stdout]     |
[INFO] [stdout]     = warning: this is accepted in the current edition (Rust 2015) but is a hard error in Rust 2021!
[INFO] [stdout]     = note: for more information, see issue #80165 <https://github.com/rust-lang/rust/issues/80165>
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: trait objects without an explicit `dyn` are deprecated
[INFO] [stdout]  --> src/nl.rs:7:25
[INFO] [stdout]   |
[INFO] [stdout] 7 |     pub activation: Box<Activation>,
[INFO] [stdout]   |                         ^^^^^^^^^^ help: use `dyn`: `dyn Activation`
[INFO] [stdout]   |
[INFO] [stdout]   = warning: this is accepted in the current edition (Rust 2015) but is a hard error in Rust 2021!
[INFO] [stdout]   = note: for more information, see issue #80165 <https://github.com/rust-lang/rust/issues/80165>
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: trait objects without an explicit `dyn` are deprecated
[INFO] [stdout]   --> src/nn.rs:15:24
[INFO] [stdout]    |
[INFO] [stdout] 15 |     cost_function: Box<CostFunction>,
[INFO] [stdout]    |                        ^^^^^^^^^^^^ help: use `dyn`: `dyn CostFunction`
[INFO] [stdout]    |
[INFO] [stdout]    = warning: this is accepted in the current edition (Rust 2015) but is a hard error in Rust 2021!
[INFO] [stdout]    = note: for more information, see issue #80165 <https://github.com/rust-lang/rust/issues/80165>
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: trait objects without an explicit `dyn` are deprecated
[INFO] [stdout]   --> src/nn.rs:17:29
[INFO] [stdout]    |
[INFO] [stdout] 17 |     on_error_fn: Option<Box<Fn(f64)>>,
[INFO] [stdout]    |                             ^^^^^^^ help: use `dyn`: `dyn Fn(f64)`
[INFO] [stdout]    |
[INFO] [stdout]    = warning: this is accepted in the current edition (Rust 2015) but is a hard error in Rust 2021!
[INFO] [stdout]    = note: for more information, see issue #80165 <https://github.com/rust-lang/rust/issues/80165>
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: trait objects without an explicit `dyn` are deprecated
[INFO] [stdout]   --> src/nn.rs:18:29
[INFO] [stdout]    |
[INFO] [stdout] 18 |     on_epoch_fn: Option<Box<Fn(&NeuralNetwork)>>,
[INFO] [stdout]    |                             ^^^^^^^^^^^^^^^^^^ help: use `dyn`: `dyn Fn(&NeuralNetwork)`
[INFO] [stdout]    |
[INFO] [stdout]    = warning: this is accepted in the current edition (Rust 2015) but is a hard error in Rust 2021!
[INFO] [stdout]    = note: for more information, see issue #80165 <https://github.com/rust-lang/rust/issues/80165>
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unnecessary parentheses around block return value
[INFO] [stdout]   --> src/cost/cross_entropy.rs:60:9
[INFO] [stdout]    |
[INFO] [stdout] 60 |         (cost.fold(0f64, |sum, val| sum + val) / target.cols() as f64)
[INFO] [stdout]    |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: remove these parentheses
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(unused_parens)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 14 warnings emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 13 warnings emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]     Finished dev [unoptimized + debuginfo] target(s) in 1.19s
[INFO] running `Command { std: "docker" "inspect" "1f64edf91f8ff728a686d8a472ceb7498a75f2d01d157e909724156f8fc45466", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "1f64edf91f8ff728a686d8a472ceb7498a75f2d01d157e909724156f8fc45466", kill_on_drop: false }`
[INFO] [stdout] 1f64edf91f8ff728a686d8a472ceb7498a75f2d01d157e909724156f8fc45466
