[INFO] fetching crate thread_io 0.2.0...
[INFO] checking thread_io-0.2.0 against try#6024cfef3a82f9a7688f07054f1650081bad3af5 for pr-74130
[INFO] extracting crate thread_io 0.2.0 into /workspace/builds/worker-9/source
[INFO] validating manifest of crates.io crate thread_io 0.2.0 on toolchain 6024cfef3a82f9a7688f07054f1650081bad3af5
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+6024cfef3a82f9a7688f07054f1650081bad3af5" "read-manifest" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[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-9/source/Cargo.toml
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+6024cfef3a82f9a7688f07054f1650081bad3af5" "generate-lockfile" "--manifest-path" "Cargo.toml" "-Zno-index-update", kill_on_drop: false }`
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+6024cfef3a82f9a7688f07054f1650081bad3af5" "fetch" "--locked" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-9/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-9/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_HOME=/opt/rustwide/cargo-home" "-e" "RUSTUP_HOME=/opt/rustwide/rustup-home" "-w" "/opt/rustwide/workdir" "-m" "1610612736" "--network" "none" "rustops/crates-build-env@sha256:819119df93c0f5eca3f29186f14981ef29945a311854d7222af07488600a2584" "/opt/rustwide/cargo-home/bin/cargo" "+6024cfef3a82f9a7688f07054f1650081bad3af5" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] 01b7dd042b9dbd02247aa99a8e0fbd1bfc415f940adcc77c4b9096b07c115341
[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" "01b7dd042b9dbd02247aa99a8e0fbd1bfc415f940adcc77c4b9096b07c115341", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "01b7dd042b9dbd02247aa99a8e0fbd1bfc415f940adcc77c4b9096b07c115341", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "01b7dd042b9dbd02247aa99a8e0fbd1bfc415f940adcc77c4b9096b07c115341", kill_on_drop: false }`
[INFO] [stdout] 01b7dd042b9dbd02247aa99a8e0fbd1bfc415f940adcc77c4b9096b07c115341
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-9/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-9/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@sha256:819119df93c0f5eca3f29186f14981ef29945a311854d7222af07488600a2584" "/opt/rustwide/cargo-home/bin/cargo" "+6024cfef3a82f9a7688f07054f1650081bad3af5" "check" "--frozen" "--all" "--all-targets" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] f1d0a57fe2022dc39a8967682774e1f420bb2e65773ab15e04cf46a03f12fa6d
[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" "f1d0a57fe2022dc39a8967682774e1f420bb2e65773ab15e04cf46a03f12fa6d", kill_on_drop: false }`
[INFO] [stderr]     Blocking waiting for file lock on package cache
[INFO] [stderr]     Checking rand_core v0.4.2
[INFO] [stderr]    Compiling maybe-uninit v2.0.0
[INFO] [stderr]     Checking lazy_static v1.4.0
[INFO] [stderr]    Compiling arrayvec v0.4.12
[INFO] [stderr]     Checking nodrop v0.1.14
[INFO] [stderr]    Compiling memoffset v0.5.5
[INFO] [stderr]     Checking num_cpus v1.13.0
[INFO] [stderr]     Checking crossbeam-utils v0.6.6
[INFO] [stderr]     Checking rand_core v0.3.1
[INFO] [stderr]     Checking rand_os v0.1.3
[INFO] [stderr]     Checking rand_pcg v0.1.2
[INFO] [stderr]     Checking rand_jitter v0.1.4
[INFO] [stderr]     Checking rand_xorshift v0.1.1
[INFO] [stderr]     Checking rand_hc v0.1.0
[INFO] [stderr]     Checking rand_isaac v0.1.1
[INFO] [stderr]     Checking rand_chacha v0.1.1
[INFO] [stderr]     Checking smallvec v0.6.13
[INFO] [stderr]     Checking crossbeam-channel v0.3.9
[INFO] [stderr]     Checking rand v0.6.5
[INFO] [stderr]     Checking crossbeam-epoch v0.7.2
[INFO] [stderr]     Checking crossbeam-deque v0.6.3
[INFO] [stderr]     Checking parking_lot_core v0.4.0
[INFO] [stderr]     Checking parking_lot v0.7.1
[INFO] [stderr]     Checking crossbeam v0.6.0
[INFO] [stderr]     Checking thread_io v0.2.0 (/opt/rustwide/workdir)
[INFO] [stdout] warning: variable does not need to be mutable
[INFO] [stdout]   --> tests/read.rs:64:25
[INFO] [stdout]    |
[INFO] [stdout] 64 |                     let mut rdr = Reader::new(text, rdr_block_size, ::std::usize::MAX);
[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]   --> tests/read.rs:68:25
[INFO] [stdout]    |
[INFO] [stdout] 68 |                     let mut rdr = Reader::new(text, rdr_block_size, ::std::usize::MAX);
[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]   --> tests/read.rs:94:17
[INFO] [stdout]    |
[INFO] [stdout] 94 |             let mut rdr = Reader::new(text, channel_bufsize, len / channel_bufsize);
[INFO] [stdout]    |                 ----^^^
[INFO] [stdout]    |                 |
[INFO] [stdout]    |                 help: remove this `mut`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 3 warnings emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: variable does not need to be mutable
[INFO] [stdout]   --> tests/write.rs:61:21
[INFO] [stdout]    |
[INFO] [stdout] 61 |                 let mut w = writer_init_finish(
[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: 1 warning emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]     Finished dev [unoptimized + debuginfo] target(s) in 6.72s
[INFO] running `Command { std: "docker" "inspect" "f1d0a57fe2022dc39a8967682774e1f420bb2e65773ab15e04cf46a03f12fa6d", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "f1d0a57fe2022dc39a8967682774e1f420bb2e65773ab15e04cf46a03f12fa6d", kill_on_drop: false }`
[INFO] [stdout] f1d0a57fe2022dc39a8967682774e1f420bb2e65773ab15e04cf46a03f12fa6d