[INFO] cloning repository https://github.com/kekonen/playground
[INFO] running `Command { std: "git" "-c" "credential.helper=" "-c" "credential.helper=/workspace/cargo-home/bin/git-credential-null" "clone" "--bare" "https://github.com/kekonen/playground" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fkekonen%2Fplayground", kill_on_drop: false }`
[INFO] [stderr] Cloning into bare repository '/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fkekonen%2Fplayground'...
[INFO] running `Command { std: "git" "rev-parse" "HEAD", kill_on_drop: false }`
[INFO] [stdout] ca0311f185f91063f3ae29ab5f0cc6a4f98f467f
[INFO] checking kekonen/playground against master#36ecbc94eb6be90bc38b2d0fdd4bfac3f34d9923 for pr-81863
[INFO] running `Command { std: "git" "clone" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fkekonen%2Fplayground" "/workspace/builds/worker-1/source", kill_on_drop: false }`
[INFO] [stderr] Cloning into '/workspace/builds/worker-1/source'...
[INFO] [stderr] done.
[INFO] validating manifest of git repo https://github.com/kekonen/playground on toolchain 36ecbc94eb6be90bc38b2d0fdd4bfac3f34d9923
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+36ecbc94eb6be90bc38b2d0fdd4bfac3f34d9923" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }`
[INFO] started tweaking git repo https://github.com/kekonen/playground
[INFO] finished tweaking git repo https://github.com/kekonen/playground
[INFO] tweaked toml for git repo https://github.com/kekonen/playground written to /workspace/builds/worker-1/source/Cargo.toml
[INFO] crate git repo https://github.com/kekonen/playground already has a lockfile, it will not be regenerated
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+36ecbc94eb6be90bc38b2d0fdd4bfac3f34d9923" "fetch" "--locked" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-1/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-1/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@sha256:21f1ed92105a0ef9b0d27ad8bdeb7f36f9f01ac17fffe3a3f3dc5241fc25d8f4" "/opt/rustwide/cargo-home/bin/cargo" "+36ecbc94eb6be90bc38b2d0fdd4bfac3f34d9923" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] ea47799cd34914723d59630a8bdf6a192ff4ee829c83d17a2205d923e2d73582
[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" "ea47799cd34914723d59630a8bdf6a192ff4ee829c83d17a2205d923e2d73582", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "ea47799cd34914723d59630a8bdf6a192ff4ee829c83d17a2205d923e2d73582", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "ea47799cd34914723d59630a8bdf6a192ff4ee829c83d17a2205d923e2d73582", kill_on_drop: false }`
[INFO] [stdout] ea47799cd34914723d59630a8bdf6a192ff4ee829c83d17a2205d923e2d73582
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-1/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-1/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@sha256:21f1ed92105a0ef9b0d27ad8bdeb7f36f9f01ac17fffe3a3f3dc5241fc25d8f4" "/opt/rustwide/cargo-home/bin/cargo" "+36ecbc94eb6be90bc38b2d0fdd4bfac3f34d9923" "check" "--frozen" "--all" "--all-targets" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] 68c6ac3c758378124379fb77d32bb0542e7861749c52b2b2228e2b57de9f60d5
[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" "68c6ac3c758378124379fb77d32bb0542e7861749c52b2b2228e2b57de9f60d5", kill_on_drop: false }`
[INFO] [stderr]     Checking playground v0.1.0 (/opt/rustwide/workdir)
[INFO] [stdout] warning: unused variable: `i`
[INFO] [stdout]    --> src/main.rs:182:30
[INFO] [stdout]     |
[INFO] [stdout] 182 |     fn get_y_at_ith_x(&self, i: usize) {
[INFO] [stdout]     |                              ^ help: if this is intentional, prefix it with an underscore: `_i`
[INFO] [stdout]     |
[INFO] [stdout]     = note: `#[warn(unused_variables)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: associated function is never used: `next`
[INFO] [stdout]   --> src/main.rs:62:8
[INFO] [stdout]    |
[INFO] [stdout] 62 |     fn next(&self) -> bool {
[INFO] [stdout]    |        ^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(dead_code)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: associated function is never used: `jump`
[INFO] [stdout]   --> src/main.rs:79:8
[INFO] [stdout]    |
[INFO] [stdout] 79 |     fn jump(&self, to: Option<usize>) -> bool {
[INFO] [stdout]    |        ^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: field is never read: `cursor`
[INFO] [stdout]    --> src/main.rs:128:5
[INFO] [stdout]     |
[INFO] [stdout] 128 |     cursor: usize,
[INFO] [stdout]     |     ^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: field is never read: `max`
[INFO] [stdout]    --> src/main.rs:129:5
[INFO] [stdout]     |
[INFO] [stdout] 129 |     max: usize,
[INFO] [stdout]     |     ^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: associated function is never used: `get_y_at_ith_x`
[INFO] [stdout]    --> src/main.rs:182:8
[INFO] [stdout]     |
[INFO] [stdout] 182 |     fn get_y_at_ith_x(&self, i: usize) {
[INFO] [stdout]     |        ^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `i`
[INFO] [stdout]    --> src/main.rs:182:30
[INFO] [stdout]     |
[INFO] [stdout] 182 |     fn get_y_at_ith_x(&self, i: usize) {
[INFO] [stdout]     |                              ^ help: if this is intentional, prefix it with an underscore: `_i`
[INFO] [stdout]     |
[INFO] [stdout]     = note: `#[warn(unused_variables)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 6 warnings emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: associated function is never used: `next`
[INFO] [stdout]   --> src/main.rs:62:8
[INFO] [stdout]    |
[INFO] [stdout] 62 |     fn next(&self) -> bool {
[INFO] [stdout]    |        ^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(dead_code)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: associated function is never used: `jump`
[INFO] [stdout]   --> src/main.rs:79:8
[INFO] [stdout]    |
[INFO] [stdout] 79 |     fn jump(&self, to: Option<usize>) -> bool {
[INFO] [stdout]    |        ^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: field is never read: `cursor`
[INFO] [stdout]    --> src/main.rs:128:5
[INFO] [stdout]     |
[INFO] [stdout] 128 |     cursor: usize,
[INFO] [stdout]     |     ^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: field is never read: `max`
[INFO] [stdout]    --> src/main.rs:129:5
[INFO] [stdout]     |
[INFO] [stdout] 129 |     max: usize,
[INFO] [stdout]     |     ^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: associated function is never used: `get_y_at_ith_x`
[INFO] [stdout]    --> src/main.rs:182:8
[INFO] [stdout]     |
[INFO] [stdout] 182 |     fn get_y_at_ith_x(&self, i: usize) {
[INFO] [stdout]     |        ^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 6 warnings emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]     Finished dev [unoptimized + debuginfo] target(s) in 0.86s
[INFO] running `Command { std: "docker" "inspect" "68c6ac3c758378124379fb77d32bb0542e7861749c52b2b2228e2b57de9f60d5", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "68c6ac3c758378124379fb77d32bb0542e7861749c52b2b2228e2b57de9f60d5", kill_on_drop: false }`
[INFO] [stdout] 68c6ac3c758378124379fb77d32bb0542e7861749c52b2b2228e2b57de9f60d5