[INFO] fetching crate jec-rccow 0.1.0...
[INFO] checking jec-rccow-0.1.0 against try#ddfd70ee3c3748e597b32f416b0d15a4f6e37685 for pr-87050
[INFO] extracting crate jec-rccow 0.1.0 into /workspace/builds/worker-0/source
[INFO] validating manifest of crates.io crate jec-rccow 0.1.0 on toolchain ddfd70ee3c3748e597b32f416b0d15a4f6e37685
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+ddfd70ee3c3748e597b32f416b0d15a4f6e37685" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }`
[INFO] started tweaking crates.io crate jec-rccow 0.1.0
[INFO] finished tweaking crates.io crate jec-rccow 0.1.0
[INFO] tweaked toml for crates.io crate jec-rccow 0.1.0 written to /workspace/builds/worker-0/source/Cargo.toml
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+ddfd70ee3c3748e597b32f416b0d15a4f6e37685" "generate-lockfile" "--manifest-path" "Cargo.toml" "-Zno-index-update", kill_on_drop: false }`
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+ddfd70ee3c3748e597b32f416b0d15a4f6e37685" "fetch" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] running `Command { std: "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" "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" "ghcr.io/rust-lang/crates-build-env/linux@sha256:34b6a614d2c27851fe6cbf88fbd1137609cefab8b10d0615aaeb6fd47975d74e" "/opt/rustwide/cargo-home/bin/cargo" "+ddfd70ee3c3748e597b32f416b0d15a4f6e37685" "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] c57ceabe61b79c9602e95b1e4daa301c7154b4cad7ec7088dd07a3b8850277d5
[INFO] running `Command { std: "docker" "start" "-a" "c57ceabe61b79c9602e95b1e4daa301c7154b4cad7ec7088dd07a3b8850277d5", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "c57ceabe61b79c9602e95b1e4daa301c7154b4cad7ec7088dd07a3b8850277d5", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "c57ceabe61b79c9602e95b1e4daa301c7154b4cad7ec7088dd07a3b8850277d5", kill_on_drop: false }`
[INFO] [stdout] c57ceabe61b79c9602e95b1e4daa301c7154b4cad7ec7088dd07a3b8850277d5
[INFO] running `Command { std: "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" "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" "ghcr.io/rust-lang/crates-build-env/linux@sha256:34b6a614d2c27851fe6cbf88fbd1137609cefab8b10d0615aaeb6fd47975d74e" "/opt/rustwide/cargo-home/bin/cargo" "+ddfd70ee3c3748e597b32f416b0d15a4f6e37685" "check" "--frozen" "--all" "--all-targets" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] ef14a798482702d8e430036061226788fc6809cbdb0ce49303fe82c47c44ef10
[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" "ef14a798482702d8e430036061226788fc6809cbdb0ce49303fe82c47c44ef10", kill_on_drop: false }`
[INFO] [stderr]     Checking jec-rccow v0.1.0 (/opt/rustwide/workdir)
[INFO] [stdout] warning: variable does not need to be mutable
[INFO] [stdout]   --> src/lib.rs:73:13
[INFO] [stdout]    |
[INFO] [stdout] 73 |         let mut a = RcCow::new(5i32);
[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/lib.rs:77:13
[INFO] [stdout]    |
[INFO] [stdout] 77 |         let mut c = b.clone();
[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 0.45s
[INFO] running `Command { std: "docker" "inspect" "ef14a798482702d8e430036061226788fc6809cbdb0ce49303fe82c47c44ef10", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "ef14a798482702d8e430036061226788fc6809cbdb0ce49303fe82c47c44ef10", kill_on_drop: false }`
[INFO] [stdout] ef14a798482702d8e430036061226788fc6809cbdb0ce49303fe82c47c44ef10