[INFO] cloning repository https://github.com/qinzhengke/rust-lang-example
[INFO] running `Command { std: "git" "-c" "credential.helper=" "-c" "credential.helper=/workspace/cargo-home/bin/git-credential-null" "clone" "--bare" "https://github.com/qinzhengke/rust-lang-example" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fqinzhengke%2Frust-lang-example", kill_on_drop: false }`
[INFO] [stderr] Cloning into bare repository '/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fqinzhengke%2Frust-lang-example'...
[INFO] running `Command { std: "git" "rev-parse" "HEAD", kill_on_drop: false }`
[INFO] [stdout] cb8fe0ad69e0de43a8d14e4063856fea3fa346aa
[INFO] checking qinzhengke/rust-lang-example against try#575650af7d7ca88602df28e39d27bf3e456c306e for pr-80579
[INFO] running `Command { std: "git" "clone" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fqinzhengke%2Frust-lang-example" "/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/qinzhengke/rust-lang-example 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/qinzhengke/rust-lang-example
[INFO] finished tweaking git repo https://github.com/qinzhengke/rust-lang-example
[INFO] tweaked toml for git repo https://github.com/qinzhengke/rust-lang-example written to /workspace/builds/worker-7/source/Cargo.toml
[INFO] crate git repo https://github.com/qinzhengke/rust-lang-example 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] 9ff6c11fb1b16575ea406980ddcdb59616ae8e8085cb801434384e6935bc7bbe
[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" "9ff6c11fb1b16575ea406980ddcdb59616ae8e8085cb801434384e6935bc7bbe", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "9ff6c11fb1b16575ea406980ddcdb59616ae8e8085cb801434384e6935bc7bbe", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "9ff6c11fb1b16575ea406980ddcdb59616ae8e8085cb801434384e6935bc7bbe", kill_on_drop: false }`
[INFO] [stdout] 9ff6c11fb1b16575ea406980ddcdb59616ae8e8085cb801434384e6935bc7bbe
[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] 288d90b1c399128d7043b473a95d08fe249ac65f14baf724be445d07d7c5191f
[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" "288d90b1c399128d7043b473a95d08fe249ac65f14baf724be445d07d7c5191f", kill_on_drop: false }`
[INFO] [stderr]     Blocking waiting for file lock on package cache
[INFO] [stderr]     Checking rust-lang-example v0.1.0 (/opt/rustwide/workdir)
[INFO] [stdout] warning: unused variable: `r2`
[INFO] [stdout]   --> src/ownership.rs:57:9
[INFO] [stdout]    |
[INFO] [stdout] 57 |     let r2 = &mut s1;
[INFO] [stdout]    |         ^^ help: if this is intentional, prefix it with an underscore: `_r2`
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(unused_variables)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `r2`
[INFO] [stdout]   --> src/ownership.rs:57:9
[INFO] [stdout]    |
[INFO] [stdout] 57 |     let r2 = &mut s1;
[INFO] [stdout]    |         ^^ help: if this is intentional, prefix it with an underscore: `_r2`
[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/ownership.rs:62:9
[INFO] [stdout]    |
[INFO] [stdout] 62 |     let mut s1 = String::from("hello");
[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: variable does not need to be mutable
[INFO] [stdout]   --> src/ownership.rs:62:9
[INFO] [stdout]    |
[INFO] [stdout] 62 |     let mut s1 = String::from("hello");
[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: variable does not need to be mutable
[INFO] [stdout]  --> src/types.rs:9:9
[INFO] [stdout]   |
[INFO] [stdout] 9 |     let mut c:i8 = -10;
[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: variable does not need to be mutable
[INFO] [stdout]   --> src/types.rs:24:9
[INFO] [stdout]    |
[INFO] [stdout] 24 |     let mut d:u8 = 255;
[INFO] [stdout]    |         ----^
[INFO] [stdout]    |         |
[INFO] [stdout]    |         help: remove this `mut`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 2 warnings emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 2 warnings emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 2 warnings emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: variable does not need to be mutable
[INFO] [stdout]  --> src/types.rs:9:9
[INFO] [stdout]   |
[INFO] [stdout] 9 |     let mut c:i8 = -10;
[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: variable does not need to be mutable
[INFO] [stdout]   --> src/types.rs:24:9
[INFO] [stdout]    |
[INFO] [stdout] 24 |     let mut d:u8 = 255;
[INFO] [stdout]    |         ----^
[INFO] [stdout]    |         |
[INFO] [stdout]    |         help: remove this `mut`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 2 warnings emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]     Finished dev [unoptimized + debuginfo] target(s) in 13.23s
[INFO] running `Command { std: "docker" "inspect" "288d90b1c399128d7043b473a95d08fe249ac65f14baf724be445d07d7c5191f", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "288d90b1c399128d7043b473a95d08fe249ac65f14baf724be445d07d7c5191f", kill_on_drop: false }`
[INFO] [stdout] 288d90b1c399128d7043b473a95d08fe249ac65f14baf724be445d07d7c5191f