[INFO] fetching crate cbuf 0.1.1...
[INFO] checking cbuf-0.1.1 against try#45d8b6e68beee1c9c1ce92ae258a7e02f8f13aa4 for pr-83744
[INFO] extracting crate cbuf 0.1.1 into /workspace/builds/worker-6/source
[INFO] validating manifest of crates.io crate cbuf 0.1.1 on toolchain 45d8b6e68beee1c9c1ce92ae258a7e02f8f13aa4
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+45d8b6e68beee1c9c1ce92ae258a7e02f8f13aa4" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }`
[INFO] started tweaking crates.io crate cbuf 0.1.1
[INFO] finished tweaking crates.io crate cbuf 0.1.1
[INFO] tweaked toml for crates.io crate cbuf 0.1.1 written to /workspace/builds/worker-6/source/Cargo.toml
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+45d8b6e68beee1c9c1ce92ae258a7e02f8f13aa4" "generate-lockfile" "--manifest-path" "Cargo.toml" "-Zno-index-update", kill_on_drop: false }`
[INFO] [stderr]     Blocking waiting for file lock on package cache
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+45d8b6e68beee1c9c1ce92ae258a7e02f8f13aa4" "fetch" "--locked" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] [stderr]     Blocking waiting for file lock on package cache
[INFO] [stderr]     Blocking waiting for file lock on package cache
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/jobserver:/tmp/crater-runner-fifo:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-6/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-6/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:c46a2d1a26fb48b37929c74ca49dd9409f2375a0a3bdb8fe07617f3ffccaa889" "/opt/rustwide/cargo-home/bin/cargo" "+45d8b6e68beee1c9c1ce92ae258a7e02f8f13aa4" "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] d9afe60ef9c5ed2d5f14927735b7a6874c6c15dcf6846c4dbc68a0c0e26f2462
[INFO] running `Command { std: "docker" "start" "-a" "d9afe60ef9c5ed2d5f14927735b7a6874c6c15dcf6846c4dbc68a0c0e26f2462", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "d9afe60ef9c5ed2d5f14927735b7a6874c6c15dcf6846c4dbc68a0c0e26f2462", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "d9afe60ef9c5ed2d5f14927735b7a6874c6c15dcf6846c4dbc68a0c0e26f2462", kill_on_drop: false }`
[INFO] [stdout] d9afe60ef9c5ed2d5f14927735b7a6874c6c15dcf6846c4dbc68a0c0e26f2462
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/jobserver:/tmp/crater-runner-fifo:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-6/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-6/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" "RUSTUP_TOOLCHAIN=45d8b6e68beee1c9c1ce92ae258a7e02f8f13aa4" "-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:c46a2d1a26fb48b37929c74ca49dd9409f2375a0a3bdb8fe07617f3ffccaa889" "/tmp/crater-runner-fifo/jobserver-crater-fwd" "/opt/rustwide/cargo-home/bin/cargo" "check" "--frozen" "--all" "--all-targets" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] df98942a86952839c0ae7740529d3e9eea382fba35364b5bdcbf94d31b420126
[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" "df98942a86952839c0ae7740529d3e9eea382fba35364b5bdcbf94d31b420126", kill_on_drop: false }`
[INFO] [stderr]     Blocking waiting for file lock on package cache
[INFO] [stderr]     Checking cbuf v0.1.1 (/opt/rustwide/workdir)
[INFO] [stdout] warning: variable does not need to be mutable
[INFO] [stdout]    --> src/lib.rs:235:13
[INFO] [stdout]     |
[INFO] [stdout] 235 |         let mut buf = &mut [0u8, 2];
[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:266:13
[INFO] [stdout]     |
[INFO] [stdout] 266 |         let mut buf = &mut [0u8, 0u8];
[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:298:13
[INFO] [stdout]     |
[INFO] [stdout] 298 |         let mut buf = &mut [0u8, 0u8];
[INFO] [stdout]     |             ----^^^
[INFO] [stdout]     |             |
[INFO] [stdout]     |             help: remove this `mut`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]     Finished dev [unoptimized + debuginfo] target(s) in 6.27s
[INFO] [stdout] warning: 3 warnings emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] running `Command { std: "docker" "inspect" "df98942a86952839c0ae7740529d3e9eea382fba35364b5bdcbf94d31b420126", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "df98942a86952839c0ae7740529d3e9eea382fba35364b5bdcbf94d31b420126", kill_on_drop: false }`
[INFO] [stdout] df98942a86952839c0ae7740529d3e9eea382fba35364b5bdcbf94d31b420126