[INFO] cloning repository https://github.com/Bkindmonk/RustPractice
[INFO] running `Command { std: "git" "-c" "credential.helper=" "-c" "credential.helper=/workspace/cargo-home/bin/git-credential-null" "clone" "--bare" "https://github.com/Bkindmonk/RustPractice" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2FBkindmonk%2FRustPractice", kill_on_drop: false }`
[INFO] [stderr] Cloning into bare repository '/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2FBkindmonk%2FRustPractice'...
[INFO] running `Command { std: "git" "rev-parse" "HEAD", kill_on_drop: false }`
[INFO] [stdout] dddc1c842ad316fb93f1f4a3a9741aea4ff490c9
[INFO] checking Bkindmonk/RustPractice against master#d62d3f7fa9a91d933213cc10e20e740608983f64 for pr-77015
[INFO] running `Command { std: "git" "clone" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2FBkindmonk%2FRustPractice" "/workspace/builds/worker-5/source", kill_on_drop: false }`
[INFO] [stderr] Cloning into '/workspace/builds/worker-5/source'...
[INFO] [stderr] done.
[INFO] validating manifest of git repo https://github.com/Bkindmonk/RustPractice on toolchain d62d3f7fa9a91d933213cc10e20e740608983f64
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+d62d3f7fa9a91d933213cc10e20e740608983f64" "read-manifest" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] started tweaking git repo https://github.com/Bkindmonk/RustPractice
[INFO] finished tweaking git repo https://github.com/Bkindmonk/RustPractice
[INFO] tweaked toml for git repo https://github.com/Bkindmonk/RustPractice written to /workspace/builds/worker-5/source/Cargo.toml
[INFO] crate git repo https://github.com/Bkindmonk/RustPractice already has a lockfile, it will not be regenerated
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+d62d3f7fa9a91d933213cc10e20e740608983f64" "fetch" "--locked" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-5/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-5/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" "+d62d3f7fa9a91d933213cc10e20e740608983f64" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] 93375f38e6953a31ba8c069ded627249a911246e1d24b5a8be93227404c3b818
[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" "93375f38e6953a31ba8c069ded627249a911246e1d24b5a8be93227404c3b818", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "93375f38e6953a31ba8c069ded627249a911246e1d24b5a8be93227404c3b818", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "93375f38e6953a31ba8c069ded627249a911246e1d24b5a8be93227404c3b818", kill_on_drop: false }`
[INFO] [stdout] 93375f38e6953a31ba8c069ded627249a911246e1d24b5a8be93227404c3b818
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-5/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-5/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" "+d62d3f7fa9a91d933213cc10e20e740608983f64" "check" "--frozen" "--all" "--all-targets" "--message-format=json", 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] 141d0b538141f7524d7e5d8d58f21ca9c9b7444312e6abfbfe257bc33e2744b8
[INFO] running `Command { std: "docker" "start" "-a" "141d0b538141f7524d7e5d8d58f21ca9c9b7444312e6abfbfe257bc33e2744b8", kill_on_drop: false }`
[INFO] [stderr]     Checking mergesort v0.1.0 (/opt/rustwide/workdir)
[INFO] [stdout] warning: variable does not need to be mutable
[INFO] [stdout]   --> src/main.rs:91:13
[INFO] [stdout]    |
[INFO] [stdout] 91 |         let mut realhalves = (*real).split_at_mut(halflength);
[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/main.rs:92:13
[INFO] [stdout]    |
[INFO] [stdout] 92 |         let mut scratchhalves = (*scratch).split_at_mut(halflength);
[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] [stdout] warning: variable does not need to be mutable
[INFO] [stdout]   --> src/main.rs:91:13
[INFO] [stdout]    |
[INFO] [stdout] 91 |         let mut realhalves = (*real).split_at_mut(halflength);
[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/main.rs:92:13
[INFO] [stdout]    |
[INFO] [stdout] 92 |         let mut scratchhalves = (*scratch).split_at_mut(halflength);
[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 0.66s
[INFO] running `Command { std: "docker" "inspect" "141d0b538141f7524d7e5d8d58f21ca9c9b7444312e6abfbfe257bc33e2744b8", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "141d0b538141f7524d7e5d8d58f21ca9c9b7444312e6abfbfe257bc33e2744b8", kill_on_drop: false }`
[INFO] [stdout] 141d0b538141f7524d7e5d8d58f21ca9c9b7444312e6abfbfe257bc33e2744b8