[INFO] cloning repository https://github.com/HsiangSun/rust_study
[INFO] running `Command { std: "git" "-c" "credential.helper=" "-c" "credential.helper=/workspace/cargo-home/bin/git-credential-null" "clone" "--bare" "https://github.com/HsiangSun/rust_study" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2FHsiangSun%2Frust_study", kill_on_drop: false }`
[INFO] [stderr] Cloning into bare repository '/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2FHsiangSun%2Frust_study'...
[INFO] running `Command { std: "git" "rev-parse" "HEAD", kill_on_drop: false }`
[INFO] [stdout] cafc19252292e98dc652fbf9ef9a99bf8a5f4cea
[INFO] checking HsiangSun/rust_study against master#195ad4830e11a544391abe296b146450dea8411b for pr-82781
[INFO] running `Command { std: "git" "clone" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2FHsiangSun%2Frust_study" "/workspace/builds/worker-3/source", kill_on_drop: false }`
[INFO] [stderr] Cloning into '/workspace/builds/worker-3/source'...
[INFO] [stderr] done.
[INFO] validating manifest of git repo https://github.com/HsiangSun/rust_study on toolchain 195ad4830e11a544391abe296b146450dea8411b
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+195ad4830e11a544391abe296b146450dea8411b" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }`
[INFO] started tweaking git repo https://github.com/HsiangSun/rust_study
[INFO] finished tweaking git repo https://github.com/HsiangSun/rust_study
[INFO] tweaked toml for git repo https://github.com/HsiangSun/rust_study written to /workspace/builds/worker-3/source/Cargo.toml
[INFO] crate git repo https://github.com/HsiangSun/rust_study already has a lockfile, it will not be regenerated
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+195ad4830e11a544391abe296b146450dea8411b" "fetch" "--locked" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-3/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-3/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:f2f6bcd4b43ebee4e173f653a26493129bdb64017c85f916b780ca7fbdbaa79d" "/opt/rustwide/cargo-home/bin/cargo" "+195ad4830e11a544391abe296b146450dea8411b" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] e9a977d407915dc0727f3cb1e19d43d5e50b9b407cc85027d0f6a6c7afcfda38
[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" "e9a977d407915dc0727f3cb1e19d43d5e50b9b407cc85027d0f6a6c7afcfda38", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "e9a977d407915dc0727f3cb1e19d43d5e50b9b407cc85027d0f6a6c7afcfda38", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "e9a977d407915dc0727f3cb1e19d43d5e50b9b407cc85027d0f6a6c7afcfda38", kill_on_drop: false }`
[INFO] [stdout] e9a977d407915dc0727f3cb1e19d43d5e50b9b407cc85027d0f6a6c7afcfda38
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-3/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-3/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:f2f6bcd4b43ebee4e173f653a26493129bdb64017c85f916b780ca7fbdbaa79d" "/opt/rustwide/cargo-home/bin/cargo" "+195ad4830e11a544391abe296b146450dea8411b" "check" "--frozen" "--all" "--all-targets" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] bff44827c4aa2fef0b8a45bc3224e1e97ffbebcbb51552f059e385d2c445aeea
[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" "bff44827c4aa2fef0b8a45bc3224e1e97ffbebcbb51552f059e385d2c445aeea", kill_on_drop: false }`
[INFO] [stderr]     Blocking waiting for file lock on package cache
[INFO] [stderr]     Checking study01 v0.1.0 (/opt/rustwide/workdir)
[INFO] [stdout] warning: unused variable: `f`
[INFO] [stdout]  --> src/io.rs:4:9
[INFO] [stdout]   |
[INFO] [stdout] 4 |     let f = File::create("./rust.txt").unwrap();
[INFO] [stdout]   |         ^ help: if this is intentional, prefix it with an underscore: `_f`
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(unused_variables)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `f`
[INFO] [stdout]  --> src/io.rs:4:9
[INFO] [stdout]   |
[INFO] [stdout] 4 |     let f = File::create("./rust.txt").unwrap();
[INFO] [stdout]   |         ^ help: if this is intentional, prefix it with an underscore: `_f`
[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] [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" "bff44827c4aa2fef0b8a45bc3224e1e97ffbebcbb51552f059e385d2c445aeea", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "bff44827c4aa2fef0b8a45bc3224e1e97ffbebcbb51552f059e385d2c445aeea", kill_on_drop: false }`
[INFO] [stdout] bff44827c4aa2fef0b8a45bc3224e1e97ffbebcbb51552f059e385d2c445aeea