[INFO] cloning repository https://github.com/rayz/learn-rust
[INFO] running `Command { std: "git" "-c" "credential.helper=" "-c" "credential.helper=/workspace/cargo-home/bin/git-credential-null" "clone" "--bare" "https://github.com/rayz/learn-rust" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Frayz%2Flearn-rust", kill_on_drop: false }`
[INFO] [stderr] Cloning into bare repository '/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Frayz%2Flearn-rust'...
[INFO] running `Command { std: "git" "rev-parse" "HEAD", kill_on_drop: false }`
[INFO] [stdout] 4f1d55c55d8e66fca1a2013200cf12eb99a48d55
[INFO] checking rayz/learn-rust against try#575650af7d7ca88602df28e39d27bf3e456c306e for pr-80579
[INFO] running `Command { std: "git" "clone" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Frayz%2Flearn-rust" "/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/rayz/learn-rust on toolchain 575650af7d7ca88602df28e39d27bf3e456c306e
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+575650af7d7ca88602df28e39d27bf3e456c306e" "read-manifest" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] started tweaking git repo https://github.com/rayz/learn-rust
[INFO] finished tweaking git repo https://github.com/rayz/learn-rust
[INFO] tweaked toml for git repo https://github.com/rayz/learn-rust written to /workspace/builds/worker-7/source/Cargo.toml
[INFO] crate git repo https://github.com/rayz/learn-rust already has a lockfile, it will not be regenerated
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+575650af7d7ca88602df28e39d27bf3e456c306e" "fetch" "--locked" "--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" "rustops/crates-build-env@sha256:b8eeb62f26c39b23691079a6cb6de528d8e88b4d71a8f6b1d30f8ba7d9c16de9" "/opt/rustwide/cargo-home/bin/cargo" "+575650af7d7ca88602df28e39d27bf3e456c306e" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] dd85590a2dcc4f12a29d8dd1b0041c0be44d30e89a6f55d2790d802eaef9a29f
[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" "dd85590a2dcc4f12a29d8dd1b0041c0be44d30e89a6f55d2790d802eaef9a29f", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "dd85590a2dcc4f12a29d8dd1b0041c0be44d30e89a6f55d2790d802eaef9a29f", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "dd85590a2dcc4f12a29d8dd1b0041c0be44d30e89a6f55d2790d802eaef9a29f", kill_on_drop: false }`
[INFO] [stdout] dd85590a2dcc4f12a29d8dd1b0041c0be44d30e89a6f55d2790d802eaef9a29f
[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=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:b8eeb62f26c39b23691079a6cb6de528d8e88b4d71a8f6b1d30f8ba7d9c16de9" "/opt/rustwide/cargo-home/bin/cargo" "+575650af7d7ca88602df28e39d27bf3e456c306e" "check" "--frozen" "--all" "--all-targets" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] 08f1482efd92c8ff346f22366407b533115df5f569075f7d40ac2882af8d6605
[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" "08f1482efd92c8ff346f22366407b533115df5f569075f7d40ac2882af8d6605", kill_on_drop: false }`
[INFO] [stderr]     Checking learn-rust v0.1.0 (/opt/rustwide/workdir)
[INFO] [stdout] warning: unused import: `std::io`
[INFO] [stdout]  --> src/bin/err_from_main.rs:2:5
[INFO] [stdout]   |
[INFO] [stdout] 2 | use std::io;
[INFO] [stdout]   |     ^^^^^^^
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(unused_imports)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `file`
[INFO] [stdout]  --> src/bin/err_from_main.rs:5:9
[INFO] [stdout]   |
[INFO] [stdout] 5 |     let mut file = File::open("foo.txt")?;
[INFO] [stdout]   |         ^^^^^^^^ help: if this is intentional, prefix it with an underscore: `_file`
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(unused_variables)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: variable does not need to be mutable
[INFO] [stdout]  --> src/bin/err_from_main.rs:5:9
[INFO] [stdout]   |
[INFO] [stdout] 5 |     let mut file = File::open("foo.txt")?;
[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: 3 warnings emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused import: `std::io`
[INFO] [stdout]  --> src/bin/err_from_main.rs:2:5
[INFO] [stdout]   |
[INFO] [stdout] 2 | use std::io;
[INFO] [stdout]   |     ^^^^^^^
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(unused_imports)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `file`
[INFO] [stdout]  --> src/bin/err_from_main.rs:5:9
[INFO] [stdout]   |
[INFO] [stdout] 5 |     let mut file = File::open("foo.txt")?;
[INFO] [stdout]   |         ^^^^^^^^ help: if this is intentional, prefix it with an underscore: `_file`
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(unused_variables)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: variable does not need to be mutable
[INFO] [stdout]  --> src/bin/err_from_main.rs:5:9
[INFO] [stdout]   |
[INFO] [stdout] 5 |     let mut file = File::open("foo.txt")?;
[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 variable: `y`
[INFO] [stdout]   --> src/bin/vec.rs:18:13
[INFO] [stdout]    |
[INFO] [stdout] 18 |         let y = i;
[INFO] [stdout]    |             ^ help: if this is intentional, prefix it with an underscore: `_y`
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(unused_variables)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function is never used: `test_iter_mut`
[INFO] [stdout]  --> src/bin/vec.rs:7:4
[INFO] [stdout]   |
[INFO] [stdout] 7 | fn test_iter_mut() {
[INFO] [stdout]   |    ^^^^^^^^^^^^^
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(dead_code)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function is never used: `test_fold`
[INFO] [stdout]   --> src/bin/vec.rs:15:4
[INFO] [stdout]    |
[INFO] [stdout] 15 | fn test_fold() {
[INFO] [stdout]    |    ^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 3 warnings emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 3 warnings emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `y`
[INFO] [stdout]   --> src/bin/vec.rs:18:13
[INFO] [stdout]    |
[INFO] [stdout] 18 |         let y = i;
[INFO] [stdout]    |             ^ help: if this is intentional, prefix it with an underscore: `_y`
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(unused_variables)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `e`
[INFO] [stdout]  --> src/bin/errs.rs:8:13
[INFO] [stdout]   |
[INFO] [stdout] 8 |         Err(e) => println!("Error reading username from file!"),
[INFO] [stdout]   |             ^ help: if this is intentional, prefix it with an underscore: `_e`
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(unused_variables)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function is never used: `test_iter_mut`
[INFO] [stdout]  --> src/bin/vec.rs:7:4
[INFO] [stdout]   |
[INFO] [stdout] 7 | fn test_iter_mut() {
[INFO] [stdout]   |    ^^^^^^^^^^^^^
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(dead_code)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function is never used: `test_fold`
[INFO] [stdout]   --> src/bin/vec.rs:15:4
[INFO] [stdout]    |
[INFO] [stdout] 15 | fn test_fold() {
[INFO] [stdout]    |    ^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 1 warning emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 3 warnings emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `e`
[INFO] [stdout]  --> src/bin/errs.rs:8:13
[INFO] [stdout]   |
[INFO] [stdout] 8 |         Err(e) => println!("Error reading username from file!"),
[INFO] [stdout]   |             ^ help: if this is intentional, prefix it with an underscore: `_e`
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(unused_variables)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 1 warning emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]     Finished dev [unoptimized + debuginfo] target(s) in 1.33s
[INFO] running `Command { std: "docker" "inspect" "08f1482efd92c8ff346f22366407b533115df5f569075f7d40ac2882af8d6605", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "08f1482efd92c8ff346f22366407b533115df5f569075f7d40ac2882af8d6605", kill_on_drop: false }`
[INFO] [stdout] 08f1482efd92c8ff346f22366407b533115df5f569075f7d40ac2882af8d6605