[INFO] fetching crate file_diff 1.0.0...
[INFO] checking file_diff-1.0.0 against master#0dce3f606e05cffab7361c132a399d3550ab0df8 for pr-78376
[INFO] extracting crate file_diff 1.0.0 into /workspace/builds/worker-4/source
[INFO] validating manifest of crates.io crate file_diff 1.0.0 on toolchain 0dce3f606e05cffab7361c132a399d3550ab0df8
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+0dce3f606e05cffab7361c132a399d3550ab0df8" "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-4/source/Cargo.toml
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+0dce3f606e05cffab7361c132a399d3550ab0df8" "generate-lockfile" "--manifest-path" "Cargo.toml" "-Zno-index-update", kill_on_drop: false }`
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+0dce3f606e05cffab7361c132a399d3550ab0df8" "fetch" "--locked" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-4/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-4/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" "+0dce3f606e05cffab7361c132a399d3550ab0df8" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] 86bd5dba52c7d57dcd4943e19092604eff8c94650402089e7cb2e1239228ea9f
[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" "86bd5dba52c7d57dcd4943e19092604eff8c94650402089e7cb2e1239228ea9f", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "86bd5dba52c7d57dcd4943e19092604eff8c94650402089e7cb2e1239228ea9f", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "86bd5dba52c7d57dcd4943e19092604eff8c94650402089e7cb2e1239228ea9f", kill_on_drop: false }`
[INFO] [stdout] 86bd5dba52c7d57dcd4943e19092604eff8c94650402089e7cb2e1239228ea9f
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-4/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-4/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" "+0dce3f606e05cffab7361c132a399d3550ab0df8" "check" "--frozen" "--all" "--all-targets" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] cde1085e57ca005ae94134833270aa59496cbedff3512ba5f2dffff80b28956f
[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" "cde1085e57ca005ae94134833270aa59496cbedff3512ba5f2dffff80b28956f", kill_on_drop: false }`
[INFO] [stderr]     Blocking waiting for file lock on package cache
[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: 2 warnings emitted
[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] [stderr]     Finished dev [unoptimized + debuginfo] target(s) in 3.97s
[INFO] running `Command { std: "docker" "inspect" "cde1085e57ca005ae94134833270aa59496cbedff3512ba5f2dffff80b28956f", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "cde1085e57ca005ae94134833270aa59496cbedff3512ba5f2dffff80b28956f", kill_on_drop: false }`
[INFO] [stdout] cde1085e57ca005ae94134833270aa59496cbedff3512ba5f2dffff80b28956f