[INFO] cloning repository https://github.com/sudokku/rust-mnist
[INFO] running `Command { std: "git" "-c" "credential.helper=" "-c" "credential.helper=/workspace/cargo-home/bin/git-credential-null" "clone" "--bare" "https://github.com/sudokku/rust-mnist" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fsudokku%2Frust-mnist", kill_on_drop: false }`
[INFO] [stderr] Cloning into bare repository '/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fsudokku%2Frust-mnist'...
[INFO] running `Command { std: "git" "rev-parse" "HEAD", kill_on_drop: false }`
[INFO] [stdout] adc092ad693c1209cb15ecdce766f77406455ce4
[INFO] checking sudokku/rust-mnist against try#8d46be77cd48fdbcced888d027457e2c9cf2aa16 for pr-142723
[INFO] running `Command { std: "git" "clone" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fsudokku%2Frust-mnist" "/workspace/builds/worker-0-tc2/source", kill_on_drop: false }`
[INFO] [stderr] Cloning into '/workspace/builds/worker-0-tc2/source'...
[INFO] [stderr] done.
[INFO] validating manifest of git repo https://github.com/sudokku/rust-mnist on toolchain 8d46be77cd48fdbcced888d027457e2c9cf2aa16
[INFO] running `Command { std: CARGO_HOME="/workspace/cargo-home" RUSTUP_HOME="/workspace/rustup-home" "/workspace/cargo-home/bin/cargo" "+8d46be77cd48fdbcced888d027457e2c9cf2aa16" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }`
[INFO] started tweaking git repo https://github.com/sudokku/rust-mnist
[INFO] finished tweaking git repo https://github.com/sudokku/rust-mnist
[INFO] tweaked toml for git repo https://github.com/sudokku/rust-mnist written to /workspace/builds/worker-0-tc2/source/Cargo.toml
[INFO] crate git repo https://github.com/sudokku/rust-mnist 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" "+8d46be77cd48fdbcced888d027457e2c9cf2aa16" "fetch" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] [stderr]     Blocking waiting for file lock on package cache
[INFO] [stderr]     Blocking waiting for file lock on package cache
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-0-tc2/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-0-tc2/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@sha256:90999bfc7ae267e83380e433d8e61a7c072ca6729e92edbae886d3423b3a6f4c" "/opt/rustwide/cargo-home/bin/cargo" "+8d46be77cd48fdbcced888d027457e2c9cf2aa16" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] 53f288faf718f70a3ef84647dddece77d901c87937608c12f2e5006d8d2948ef
[INFO] running `Command { std: "docker" "start" "-a" "53f288faf718f70a3ef84647dddece77d901c87937608c12f2e5006d8d2948ef", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "53f288faf718f70a3ef84647dddece77d901c87937608c12f2e5006d8d2948ef", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "53f288faf718f70a3ef84647dddece77d901c87937608c12f2e5006d8d2948ef", kill_on_drop: false }`
[INFO] [stdout] 53f288faf718f70a3ef84647dddece77d901c87937608c12f2e5006d8d2948ef
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-0-tc2/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-0-tc2/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" "RUSTDOCFLAGS=--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" "ghcr.io/rust-lang/crates-build-env/linux@sha256:90999bfc7ae267e83380e433d8e61a7c072ca6729e92edbae886d3423b3a6f4c" "/opt/rustwide/cargo-home/bin/cargo" "+8d46be77cd48fdbcced888d027457e2c9cf2aa16" "check" "--frozen" "--all" "--all-targets" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] 0bd647acf71025e062aea088ba09e3011d7176a48ef1287fde3309a1904b0b9d
[INFO] running `Command { std: "docker" "start" "-a" "0bd647acf71025e062aea088ba09e3011d7176a48ef1287fde3309a1904b0b9d", kill_on_drop: false }`
[INFO] [stderr]    Compiling libc v0.2.151
[INFO] [stderr]     Checking cfg-if v1.0.0
[INFO] [stderr]     Checking ppv-lite86 v0.2.17
[INFO] [stderr]     Checking getrandom v0.2.11
[INFO] [stderr]     Checking rand_core v0.6.4
[INFO] [stderr]     Checking rand_chacha v0.3.1
[INFO] [stderr]     Checking rand v0.8.5
[INFO] [stderr]     Checking rust-mnist v0.1.0 (/opt/rustwide/workdir)
[INFO] [stdout] warning: variable does not need to be mutable
[INFO] [stdout]   --> src/main.rs:64:13
[INFO] [stdout]    |
[INFO] [stdout] 64 |         let mut error = layer_input
[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: field `size` is never read
[INFO] [stdout]  --> src/layer.rs:5:5
[INFO] [stdout]   |
[INFO] [stdout] 4 | pub struct Layer{
[INFO] [stdout]   |            ----- field in this struct
[INFO] [stdout] 5 |     size: usize,
[INFO] [stdout]   |     ^^^^
[INFO] [stdout]   |
[INFO] [stdout]   = note: `Layer` has a derived impl for the trait `Debug`, but this is intentionally ignored during dead code analysis
[INFO] [stdout]   = note: `#[warn(dead_code)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: variants `ReLU` and `Identity` are never constructed
[INFO] [stdout]  --> src/activation.rs:6:5
[INFO] [stdout]   |
[INFO] [stdout] 4 | pub enum ActivationFunction {
[INFO] [stdout]   |          ------------------ variants in this enum
[INFO] [stdout] 5 |     Sigmoid,
[INFO] [stdout] 6 |     ReLU,
[INFO] [stdout]   |     ^^^^
[INFO] [stdout] 7 |     Identity,
[INFO] [stdout]   |     ^^^^^^^^
[INFO] [stdout]   |
[INFO] [stdout]   = note: `ActivationFunction` has derived impls for the traits `Debug` and `Clone`, but these are intentionally ignored during dead code analysis
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: variable does not need to be mutable
[INFO] [stdout]   --> src/main.rs:64:13
[INFO] [stdout]    |
[INFO] [stdout] 64 |         let mut error = layer_input
[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: field `size` is never read
[INFO] [stdout]  --> src/layer.rs:5:5
[INFO] [stdout]   |
[INFO] [stdout] 4 | pub struct Layer{
[INFO] [stdout]   |            ----- field in this struct
[INFO] [stdout] 5 |     size: usize,
[INFO] [stdout]   |     ^^^^
[INFO] [stdout]   |
[INFO] [stdout]   = note: `Layer` has a derived impl for the trait `Debug`, but this is intentionally ignored during dead code analysis
[INFO] [stdout]   = note: `#[warn(dead_code)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: variants `ReLU` and `Identity` are never constructed
[INFO] [stdout]  --> src/activation.rs:6:5
[INFO] [stdout]   |
[INFO] [stdout] 4 | pub enum ActivationFunction {
[INFO] [stdout]   |          ------------------ variants in this enum
[INFO] [stdout] 5 |     Sigmoid,
[INFO] [stdout] 6 |     ReLU,
[INFO] [stdout]   |     ^^^^
[INFO] [stdout] 7 |     Identity,
[INFO] [stdout]   |     ^^^^^^^^
[INFO] [stdout]   |
[INFO] [stdout]   = note: `ActivationFunction` has derived impls for the traits `Debug` and `Clone`, but these are intentionally ignored during dead code analysis
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]     Finished `dev` profile [unoptimized + debuginfo] target(s) in 2.19s
[INFO] running `Command { std: "docker" "inspect" "0bd647acf71025e062aea088ba09e3011d7176a48ef1287fde3309a1904b0b9d", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "0bd647acf71025e062aea088ba09e3011d7176a48ef1287fde3309a1904b0b9d", kill_on_drop: false }`
[INFO] [stdout] 0bd647acf71025e062aea088ba09e3011d7176a48ef1287fde3309a1904b0b9d