[INFO] cloning repository https://github.com/sambrolia/play_ground
[INFO] running `"git" "-c" "credential.helper=" "-c" "credential.helper=/workspace/cargo-home/bin/git-credential-null" "clone" "--bare" "https://github.com/sambrolia/play_ground" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fsambrolia%2Fplay_ground"`
[INFO] [stderr] Cloning into bare repository '/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fsambrolia%2Fplay_ground'...
[INFO] running `"git" "rev-parse" "HEAD"`
[INFO] [stdout] cf849fb9e55de7d173931e3a6e0ab86c22698ecf
[INFO] checking sambrolia/play_ground against master#2748a9fd93dd1a00a4521f4f16de5befbf77f6cd for pr-62262-1
[INFO] running `"git" "clone" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fsambrolia%2Fplay_ground" "/workspace/builds/worker-0/source"`
[INFO] [stderr] Cloning into '/workspace/builds/worker-0/source'...
[INFO] [stderr] done.
[INFO] validating manifest of git repo https://github.com/sambrolia/play_ground on toolchain 2748a9fd93dd1a00a4521f4f16de5befbf77f6cd
[INFO] running `"/workspace/cargo-home/bin/cargo" "+2748a9fd93dd1a00a4521f4f16de5befbf77f6cd" "read-manifest" "--manifest-path" "Cargo.toml"`
[INFO] started tweaking git repo https://github.com/sambrolia/play_ground
[INFO] finished tweaking git repo https://github.com/sambrolia/play_ground
[INFO] tweaked toml for git repo https://github.com/sambrolia/play_ground written to /workspace/builds/worker-0/source/Cargo.toml
[INFO] crate git repo https://github.com/sambrolia/play_ground already has a lockfile, it will not be regenerated
[INFO] running `"/workspace/cargo-home/bin/cargo" "+2748a9fd93dd1a00a4521f4f16de5befbf77f6cd" "fetch" "--locked" "--manifest-path" "Cargo.toml"`
[INFO] running `"docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-0/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-0/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" "MAP_USER_ID=0" "-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" "--network" "none" "rustops/crates-build-env" "/opt/rustwide/cargo-home/bin/cargo" "+2748a9fd93dd1a00a4521f4f16de5befbf77f6cd" "check" "--frozen" "--all" "--all-targets"`
[INFO] [stderr] WARNING: Your kernel does not support swap limit capabilities or the cgroup is not mounted. Memory limited without swap.
[INFO] [stdout] a15e09291077ebb011b226e48c20f9936a5da6d627c252c426089755f3dd4ab0
[INFO] running `"docker" "start" "-a" "a15e09291077ebb011b226e48c20f9936a5da6d627c252c426089755f3dd4ab0"`
[INFO] [stderr]     Checking play_ground v0.1.0 (/opt/rustwide/workdir)
[INFO] [stderr] warning: unused variable: `x`
[INFO] [stderr]   --> src/main.rs:54:9
[INFO] [stderr]    |
[INFO] [stderr] 54 |     let x = 1;
[INFO] [stderr]    |         ^ help: consider prefixing with an underscore: `_x`
[INFO] [stderr]    |
[INFO] [stderr]    = note: `#[warn(unused_variables)]` on by default
[INFO] [stderr] 
[INFO] [stderr] warning: unused variable: `a`
[INFO] [stderr]   --> src/main.rs:56:13
[INFO] [stderr]    |
[INFO] [stderr] 56 |         let a = 10;
[INFO] [stderr]    |             ^ help: consider prefixing with an underscore: `_a`
[INFO] [stderr] 
[INFO] [stderr] warning: unused variable: `x`
[INFO] [stderr]   --> src/main.rs:54:9
[INFO] [stderr]    |
[INFO] [stderr] 54 |     let x = 1;
[INFO] [stderr]    |         ^ help: consider prefixing with an underscore: `_x`
[INFO] [stderr]    |
[INFO] [stderr]    = note: `#[warn(unused_variables)]` on by default
[INFO] [stderr] 
[INFO] [stderr] warning: unused variable: `a`
[INFO] [stderr]   --> src/main.rs:56:13
[INFO] [stderr]    |
[INFO] [stderr] 56 |         let a = 10;
[INFO] [stderr]    |             ^ help: consider prefixing with an underscore: `_a`
[INFO] [stderr] 
[INFO] [stderr]     Finished dev [unoptimized + debuginfo] target(s) in 0.45s
[INFO] running `"docker" "inspect" "a15e09291077ebb011b226e48c20f9936a5da6d627c252c426089755f3dd4ab0"`
[INFO] running `"docker" "rm" "-f" "a15e09291077ebb011b226e48c20f9936a5da6d627c252c426089755f3dd4ab0"`
[INFO] [stdout] a15e09291077ebb011b226e48c20f9936a5da6d627c252c426089755f3dd4ab0