[INFO] fetching crate wordtop 0.1.6...
[INFO] checking wordtop-0.1.6 against master#642c19bfc3a5c1de985bf5d0cc8207ac9d22708a for pr-148577
[INFO] extracting crate wordtop 0.1.6 into /workspace/builds/worker-6-tc1/source
[INFO] started tweaking crates.io crate wordtop 0.1.6
[INFO] finished tweaking crates.io crate wordtop 0.1.6
[INFO] tweaked toml for crates.io crate wordtop 0.1.6 written to /workspace/builds/worker-6-tc1/source/Cargo.toml
[INFO] validating manifest of crates.io crate wordtop 0.1.6 on toolchain 642c19bfc3a5c1de985bf5d0cc8207ac9d22708a
[INFO] running `Command { std: CARGO_HOME="/workspace/cargo-home" RUSTUP_HOME="/workspace/rustup-home" "/workspace/cargo-home/bin/cargo" "+642c19bfc3a5c1de985bf5d0cc8207ac9d22708a" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }`
[INFO] crate crates.io crate wordtop 0.1.6 already has a lockfile, it will not be regenerated
[INFO] running `Command { std: CARGO_HOME="/workspace/cargo-home" RUSTUP_HOME="/workspace/rustup-home" "/workspace/cargo-home/bin/cargo" "+642c19bfc3a5c1de985bf5d0cc8207ac9d22708a" "fetch" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] [stderr]     Blocking waiting for file lock on package cache
[INFO] [stderr]  Downloading crates ...
[INFO] [stderr]   Downloaded ctrlc v3.2.1
[INFO] [stderr]   Downloaded nix v0.23.0
[INFO] [stderr]   Downloaded libc v0.2.108
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-6-tc1/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-6-tc1/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@sha256:4848fb76d95f26979359cc7e45710b1dbc8f3acb7aeedee7c460d7702230f228" "/opt/rustwide/cargo-home/bin/cargo" "+642c19bfc3a5c1de985bf5d0cc8207ac9d22708a" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] b1f61761fa6f72e2112d57f07a70fe05b71e6a6c3cd8724d1f16fc9443d6532d
[INFO] running `Command { std: "docker" "start" "-a" "b1f61761fa6f72e2112d57f07a70fe05b71e6a6c3cd8724d1f16fc9443d6532d", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "b1f61761fa6f72e2112d57f07a70fe05b71e6a6c3cd8724d1f16fc9443d6532d", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "b1f61761fa6f72e2112d57f07a70fe05b71e6a6c3cd8724d1f16fc9443d6532d", kill_on_drop: false }`
[INFO] [stdout] b1f61761fa6f72e2112d57f07a70fe05b71e6a6c3cd8724d1f16fc9443d6532d
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-6-tc1/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-6-tc1/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" "RUSTDOCFLAGS=--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@sha256:4848fb76d95f26979359cc7e45710b1dbc8f3acb7aeedee7c460d7702230f228" "/opt/rustwide/cargo-home/bin/cargo" "+642c19bfc3a5c1de985bf5d0cc8207ac9d22708a" "check" "--frozen" "--all" "--all-targets" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] 9884d98b04db9a24eb5898374e10d15ef10d6b208efab50cf0951570dabe0069
[INFO] running `Command { std: "docker" "start" "-a" "9884d98b04db9a24eb5898374e10d15ef10d6b208efab50cf0951570dabe0069", kill_on_drop: false }`
[INFO] [stderr]    Compiling libc v0.2.108
[INFO] [stderr]     Checking nix v0.23.0
[INFO] [stderr]     Checking atty v0.2.14
[INFO] [stderr]     Checking clap v2.34.0
[INFO] [stderr]     Checking ctrlc v3.2.1
[INFO] [stderr]     Checking wordtop v0.1.6 (/opt/rustwide/workdir)
[INFO] [stdout] warning: value assigned to `count` is never read
[INFO] [stdout]   --> src/print.rs:21:17
[INFO] [stdout]    |
[INFO] [stdout] 21 |                 count = 0;
[INFO] [stdout]    |                 ^^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = help: maybe it is overwritten before being read?
[INFO] [stdout]    = note: `#[warn(unused_assignments)]` (part of `#[warn(unused)]`) on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: value assigned to `count` is never read
[INFO] [stdout]   --> src/print.rs:21:17
[INFO] [stdout]    |
[INFO] [stdout] 21 |                 count = 0;
[INFO] [stdout]    |                 ^^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = help: maybe it is overwritten before being read?
[INFO] [stdout]    = note: `#[warn(unused_assignments)]` (part of `#[warn(unused)]`) on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: variable does not need to be mutable
[INFO] [stdout]   --> src/print.rs:76:14
[INFO] [stdout]    |
[INFO] [stdout] 76 |         let (mut k, mut t) = print_stats(&x, 10, 10);
[INFO] [stdout]    |              ----^
[INFO] [stdout]    |              |
[INFO] [stdout]    |              help: remove this `mut`
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(unused_mut)]` (part of `#[warn(unused)]`) on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: variable does not need to be mutable
[INFO] [stdout]   --> src/print.rs:76:21
[INFO] [stdout]    |
[INFO] [stdout] 76 |         let (mut k, mut t) = print_stats(&x, 10, 10);
[INFO] [stdout]    |                     ----^
[INFO] [stdout]    |                     |
[INFO] [stdout]    |                     help: remove this `mut`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `k`
[INFO] [stdout]   --> src/print.rs:76:14
[INFO] [stdout]    |
[INFO] [stdout] 76 |         let (mut k, mut t) = print_stats(&x, 10, 10);
[INFO] [stdout]    |              ^^^^^ help: if this is intentional, prefix it with an underscore: `_k`
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(unused_variables)]` (part of `#[warn(unused)]`) on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `t`
[INFO] [stdout]   --> src/print.rs:76:21
[INFO] [stdout]    |
[INFO] [stdout] 76 |         let (mut k, mut t) = print_stats(&x, 10, 10);
[INFO] [stdout]    |                     ^^^^^ help: if this is intentional, prefix it with an underscore: `_t`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]     Finished `dev` profile [unoptimized + debuginfo] target(s) in 4.91s
[INFO] running `Command { std: "docker" "inspect" "9884d98b04db9a24eb5898374e10d15ef10d6b208efab50cf0951570dabe0069", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "9884d98b04db9a24eb5898374e10d15ef10d6b208efab50cf0951570dabe0069", kill_on_drop: false }`
[INFO] [stdout] 9884d98b04db9a24eb5898374e10d15ef10d6b208efab50cf0951570dabe0069