[INFO] fetching crate file_diff 1.0.0...
[INFO] checking file_diff-1.0.0 against try#3e22d1f9053c0fc87629b3c6d5d9567856368e5d for pr-78714
[INFO] extracting crate file_diff 1.0.0 into /workspace/builds/worker-12/source
[INFO] validating manifest of crates.io crate file_diff 1.0.0 on toolchain 3e22d1f9053c0fc87629b3c6d5d9567856368e5d
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+3e22d1f9053c0fc87629b3c6d5d9567856368e5d" "read-manifest" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] started tweaking crates.io crate file_diff 1.0.0
[INFO] finished tweaking crates.io crate file_diff 1.0.0
[INFO] tweaked toml for crates.io crate file_diff 1.0.0 written to /workspace/builds/worker-12/source/Cargo.toml
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+3e22d1f9053c0fc87629b3c6d5d9567856368e5d" "generate-lockfile" "--manifest-path" "Cargo.toml" "-Zno-index-update", kill_on_drop: false }`
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+3e22d1f9053c0fc87629b3c6d5d9567856368e5d" "fetch" "--locked" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-12/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-12/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@sha256:6eabd152ff4036248d66efda456a36cb33d24b7291b33f25f75140726c88da35" "/opt/rustwide/cargo-home/bin/cargo" "+3e22d1f9053c0fc87629b3c6d5d9567856368e5d" "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] da5882f3569d4def9472b3e0b64a0ed3575c90868a23b7ec5c7ec3c2e12d77ac
[INFO] running `Command { std: "docker" "start" "-a" "da5882f3569d4def9472b3e0b64a0ed3575c90868a23b7ec5c7ec3c2e12d77ac", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "da5882f3569d4def9472b3e0b64a0ed3575c90868a23b7ec5c7ec3c2e12d77ac", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "da5882f3569d4def9472b3e0b64a0ed3575c90868a23b7ec5c7ec3c2e12d77ac", kill_on_drop: false }`
[INFO] [stdout] da5882f3569d4def9472b3e0b64a0ed3575c90868a23b7ec5c7ec3c2e12d77ac
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-12/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-12/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@sha256:6eabd152ff4036248d66efda456a36cb33d24b7291b33f25f75140726c88da35" "/opt/rustwide/cargo-home/bin/cargo" "+3e22d1f9053c0fc87629b3c6d5d9567856368e5d" "check" "--frozen" "--all" "--all-targets" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] 69d776bf07ef158879287b5b69604ec04e5927357ec506b4ed6efc0fb2a7ca93
[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" "69d776bf07ef158879287b5b69604ec04e5927357ec506b4ed6efc0fb2a7ca93", kill_on_drop: false }`
[INFO] [stderr]     Checking file_diff v1.0.0 (/opt/rustwide/workdir)
[INFO] [stdout] warning: variable does not need to be mutable
[INFO] [stdout]   --> src/lib.rs:49:9
[INFO] [stdout]    |
[INFO] [stdout] 49 |     let mut buff1 : &mut [u8] = &mut [0; 1024];
[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:50:9
[INFO] [stdout]    |
[INFO] [stdout] 50 |     let mut buff2 : &mut [u8] = &mut [0; 1024];
[INFO] [stdout]    |         ----^^^^^
[INFO] [stdout]    |         |
[INFO] [stdout]    |         help: remove this `mut`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: variable does not need to be mutable
[INFO] [stdout]   --> src/lib.rs:49:9
[INFO] [stdout]    |
[INFO] [stdout] 49 |     let mut buff1 : &mut [u8] = &mut [0; 1024];
[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:50:9
[INFO] [stdout]    |
[INFO] [stdout] 50 |     let mut buff2 : &mut [u8] = &mut [0; 1024];
[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: 2 warnings emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]     Finished dev [unoptimized + debuginfo] target(s) in 0.27s
[INFO] running `Command { std: "docker" "inspect" "69d776bf07ef158879287b5b69604ec04e5927357ec506b4ed6efc0fb2a7ca93", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "69d776bf07ef158879287b5b69604ec04e5927357ec506b4ed6efc0fb2a7ca93", kill_on_drop: false }`
[INFO] [stdout] 69d776bf07ef158879287b5b69604ec04e5927357ec506b4ed6efc0fb2a7ca93