[INFO] crate thread_io 0.2.0 is already in cache
[INFO] checking thread_io-0.2.0 against try#1a608893c03d7722effeb0058e82770bd36b4b3c for pr-66504-1
[INFO] extracting crate thread_io 0.2.0 into /workspace/builds/worker-12/source
[INFO] validating manifest of crates.io crate thread_io 0.2.0 on toolchain 1a608893c03d7722effeb0058e82770bd36b4b3c
[INFO] running `"/workspace/cargo-home/bin/cargo" "+1a608893c03d7722effeb0058e82770bd36b4b3c" "read-manifest" "--manifest-path" "Cargo.toml"`
[INFO] started tweaking crates.io crate thread_io 0.2.0
[INFO] finished tweaking crates.io crate thread_io 0.2.0
[INFO] tweaked toml for crates.io crate thread_io 0.2.0 written to /workspace/builds/worker-12/source/Cargo.toml
[INFO] running `"/workspace/cargo-home/bin/cargo" "+1a608893c03d7722effeb0058e82770bd36b4b3c" "generate-lockfile" "--manifest-path" "Cargo.toml" "-Zno-index-update"`
[INFO] running `"/workspace/cargo-home/bin/cargo" "+1a608893c03d7722effeb0058e82770bd36b4b3c" "fetch" "--locked" "--manifest-path" "Cargo.toml"`
[INFO] [stderr]     Blocking waiting for file lock on package cache
[INFO] running `"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" "MAP_USER_ID=0" "-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" "--network" "none" "rustops/crates-build-env" "/opt/rustwide/cargo-home/bin/cargo" "+1a608893c03d7722effeb0058e82770bd36b4b3c" "check" "--frozen" "--all" "--all-targets"`
[INFO] [stderr] WARNING: Your kernel does not support swap limit capabilities or the cgroup is not mounted. Memory limited without swap.
[INFO] [stdout] 1ee2f7601e913d2627406acaada4dce30deb690a59f8e458cc69c11743ca523e
[INFO] running `"docker" "start" "-a" "1ee2f7601e913d2627406acaada4dce30deb690a59f8e458cc69c11743ca523e"`
[INFO] [stderr]     Blocking waiting for file lock on package cache
[INFO] [stderr]     Checking parking_lot_core v0.4.0
[INFO] [stderr]     Checking crossbeam-epoch v0.7.2
[INFO] [stderr]     Checking parking_lot v0.7.1
[INFO] [stderr]     Checking crossbeam-deque v0.6.3
[INFO] [stderr]     Checking crossbeam v0.6.0
[INFO] [stderr]     Checking thread_io v0.2.0 (/opt/rustwide/workdir)
[INFO] [stderr] warning: variable does not need to be mutable
[INFO] [stderr]   --> tests/read.rs:64:25
[INFO] [stderr]    |
[INFO] [stderr] 64 |                     let mut rdr = Reader::new(text, rdr_block_size, ::std::usize::MAX);
[INFO] [stderr]    |                         ----^^^
[INFO] [stderr]    |                         |
[INFO] [stderr]    |                         help: remove this `mut`
[INFO] [stderr]    |
[INFO] [stderr]    = note: `#[warn(unused_mut)]` on by default
[INFO] [stderr] 
[INFO] [stderr] warning: variable does not need to be mutable
[INFO] [stderr]   --> tests/read.rs:68:25
[INFO] [stderr]    |
[INFO] [stderr] 68 |                     let mut rdr = Reader::new(text, rdr_block_size, ::std::usize::MAX);
[INFO] [stderr]    |                         ----^^^
[INFO] [stderr]    |                         |
[INFO] [stderr]    |                         help: remove this `mut`
[INFO] [stderr] 
[INFO] [stderr] warning: variable does not need to be mutable
[INFO] [stderr]   --> tests/read.rs:94:17
[INFO] [stderr]    |
[INFO] [stderr] 94 |             let mut rdr = Reader::new(text, channel_bufsize, len / channel_bufsize);
[INFO] [stderr]    |                 ----^^^
[INFO] [stderr]    |                 |
[INFO] [stderr]    |                 help: remove this `mut`
[INFO] [stderr] 
[INFO] [stderr] warning: variable does not need to be mutable
[INFO] [stderr]   --> tests/write.rs:61:21
[INFO] [stderr]    |
[INFO] [stderr] 61 |                 let mut w = writer_init_finish(
[INFO] [stderr]    |                     ----^
[INFO] [stderr]    |                     |
[INFO] [stderr]    |                     help: remove this `mut`
[INFO] [stderr]    |
[INFO] [stderr]    = note: `#[warn(unused_mut)]` on by default
[INFO] [stderr] 
[INFO] [stderr]     Finished dev [unoptimized + debuginfo] target(s) in 5.18s
[INFO] running `"docker" "inspect" "1ee2f7601e913d2627406acaada4dce30deb690a59f8e458cc69c11743ca523e"`
[INFO] running `"docker" "rm" "-f" "1ee2f7601e913d2627406acaada4dce30deb690a59f8e458cc69c11743ca523e"`
[INFO] [stdout] 1ee2f7601e913d2627406acaada4dce30deb690a59f8e458cc69c11743ca523e