[INFO] cloning repository https://github.com/kamranajabbar/ch_09_errors
[INFO] running `Command { std: "git" "-c" "credential.helper=" "-c" "credential.helper=/workspace/cargo-home/bin/git-credential-null" "clone" "--bare" "https://github.com/kamranajabbar/ch_09_errors" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fkamranajabbar%2Fch_09_errors", kill_on_drop: false }`
[INFO] [stderr] Cloning into bare repository '/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fkamranajabbar%2Fch_09_errors'...
[INFO] running `Command { std: "git" "rev-parse" "HEAD", kill_on_drop: false }`
[INFO] [stdout] 8ed3adeb11b05b477de5d843bbdeb920c87d6f5d
[INFO] checking kamranajabbar/ch_09_errors against master#d902752866cbbdb331e3cf28ff6bba86ab0f6c62 for pr-77271
[INFO] running `Command { std: "git" "clone" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fkamranajabbar%2Fch_09_errors" "/workspace/builds/worker-13/source", kill_on_drop: false }`
[INFO] [stderr] Cloning into '/workspace/builds/worker-13/source'...
[INFO] [stderr] done.
[INFO] validating manifest of git repo https://github.com/kamranajabbar/ch_09_errors on toolchain d902752866cbbdb331e3cf28ff6bba86ab0f6c62
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+d902752866cbbdb331e3cf28ff6bba86ab0f6c62" "read-manifest" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] started tweaking git repo https://github.com/kamranajabbar/ch_09_errors
[INFO] finished tweaking git repo https://github.com/kamranajabbar/ch_09_errors
[INFO] tweaked toml for git repo https://github.com/kamranajabbar/ch_09_errors written to /workspace/builds/worker-13/source/Cargo.toml
[INFO] crate git repo https://github.com/kamranajabbar/ch_09_errors already has a lockfile, it will not be regenerated
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+d902752866cbbdb331e3cf28ff6bba86ab0f6c62" "fetch" "--locked" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-13/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-13/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:d92eaeed33fa75130ca1ee6c8a01d1ffb62bac859dfdfb3450e3e5d1c0146529" "/opt/rustwide/cargo-home/bin/cargo" "+d902752866cbbdb331e3cf28ff6bba86ab0f6c62" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stderr] WARNING: Your kernel does not support swap limit capabilities or the cgroup is not mounted. Memory limited without swap.
[INFO] [stdout] 9c543833ad3e16c0bccaa55bf3b97f621b2136159139403f874c5a14ca4d5c2b
[INFO] running `Command { std: "docker" "start" "-a" "9c543833ad3e16c0bccaa55bf3b97f621b2136159139403f874c5a14ca4d5c2b", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "9c543833ad3e16c0bccaa55bf3b97f621b2136159139403f874c5a14ca4d5c2b", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "9c543833ad3e16c0bccaa55bf3b97f621b2136159139403f874c5a14ca4d5c2b", kill_on_drop: false }`
[INFO] [stdout] 9c543833ad3e16c0bccaa55bf3b97f621b2136159139403f874c5a14ca4d5c2b
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-13/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-13/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:d92eaeed33fa75130ca1ee6c8a01d1ffb62bac859dfdfb3450e3e5d1c0146529" "/opt/rustwide/cargo-home/bin/cargo" "+d902752866cbbdb331e3cf28ff6bba86ab0f6c62" "check" "--frozen" "--all" "--all-targets" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] 7e81250b7df6baa88eea2f985faa65bd8522fcf855f8058d45a4cd9814c420d7
[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" "7e81250b7df6baa88eea2f985faa65bd8522fcf855f8058d45a4cd9814c420d7", kill_on_drop: false }`
[INFO] [stderr]     Checking errors v0.1.0 (/opt/rustwide/workdir)
[INFO] [stdout] warning: unused variable: `f`
[INFO] [stdout]   --> src/result_recoverable_errors.rs:11:9
[INFO] [stdout]    |
[INFO] [stdout] 11 |     let f = match f {
[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/result_recoverable_errors.rs:11:9
[INFO] [stdout]    |
[INFO] [stdout] 11 |     let f = match f {
[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 0.62s
[INFO] running `Command { std: "docker" "inspect" "7e81250b7df6baa88eea2f985faa65bd8522fcf855f8058d45a4cd9814c420d7", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "7e81250b7df6baa88eea2f985faa65bd8522fcf855f8058d45a4cd9814c420d7", kill_on_drop: false }`
[INFO] [stdout] 7e81250b7df6baa88eea2f985faa65bd8522fcf855f8058d45a4cd9814c420d7