[INFO] fetching crate wutf 0.1.0...
[INFO] checking wutf-0.1.0 against master#c724b67e1b474262917a5154d74e7072267593fe for pr-74315
[INFO] extracting crate wutf 0.1.0 into /workspace/builds/worker-4/source
[INFO] validating manifest of crates.io crate wutf 0.1.0 on toolchain c724b67e1b474262917a5154d74e7072267593fe
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+c724b67e1b474262917a5154d74e7072267593fe" "read-manifest" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] started tweaking crates.io crate wutf 0.1.0
[INFO] finished tweaking crates.io crate wutf 0.1.0
[INFO] tweaked toml for crates.io crate wutf 0.1.0 written to /workspace/builds/worker-4/source/Cargo.toml
[INFO] crate crates.io crate wutf 0.1.0 already has a lockfile, it will not be regenerated
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+c724b67e1b474262917a5154d74e7072267593fe" "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" "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:d9fbb4e2287ab3795bdefaf705efb7541a8875c13bce71e067d6b01dc5ed759b" "/opt/rustwide/cargo-home/bin/cargo" "+c724b67e1b474262917a5154d74e7072267593fe" "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] 68ea79b1e97733d5b2e93c7bd3e5dc8efe847b76e431b3489fc85a5e2bfa54ca
[INFO] running `Command { std: "docker" "start" "-a" "68ea79b1e97733d5b2e93c7bd3e5dc8efe847b76e431b3489fc85a5e2bfa54ca", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "68ea79b1e97733d5b2e93c7bd3e5dc8efe847b76e431b3489fc85a5e2bfa54ca", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "68ea79b1e97733d5b2e93c7bd3e5dc8efe847b76e431b3489fc85a5e2bfa54ca", kill_on_drop: false }`
[INFO] [stdout] 68ea79b1e97733d5b2e93c7bd3e5dc8efe847b76e431b3489fc85a5e2bfa54ca
[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" "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:d9fbb4e2287ab3795bdefaf705efb7541a8875c13bce71e067d6b01dc5ed759b" "/opt/rustwide/cargo-home/bin/cargo" "+c724b67e1b474262917a5154d74e7072267593fe" "check" "--frozen" "--all" "--all-targets" "--message-format=json", 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] 08c9493a43d5a7b2699c4314023ca9b5b5e3215b86dcd33c1fbda00e4897ccec
[INFO] running `Command { std: "docker" "start" "-a" "08c9493a43d5a7b2699c4314023ca9b5b5e3215b86dcd33c1fbda00e4897ccec", 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] [stderr]     Checking chardet v0.2.4
[INFO] [stderr]     Checking wutf v0.1.0 (/opt/rustwide/workdir)
[INFO] [stdout] warning: unused import: `std::io::BufReader`
[INFO] [stdout]  --> src/main.rs:1:5
[INFO] [stdout]   |
[INFO] [stdout] 1 | use std::io::BufReader;
[INFO] [stdout]   |     ^^^^^^^^^^^^^^^^^^
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(unused_imports)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused import: `BufRead`
[INFO] [stdout]  --> src/main.rs:2:21
[INFO] [stdout]   |
[INFO] [stdout] 2 | use std::io::{self, BufRead, Read, Write};
[INFO] [stdout]   |                     ^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused import: `std::io::BufReader`
[INFO] [stdout]  --> src/main.rs:1:5
[INFO] [stdout]   |
[INFO] [stdout] 1 | use std::io::BufReader;
[INFO] [stdout]   |     ^^^^^^^^^^^^^^^^^^
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(unused_imports)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused import: `BufRead`
[INFO] [stdout]  --> src/main.rs:2:21
[INFO] [stdout]   |
[INFO] [stdout] 2 | use std::io::{self, BufRead, Read, Write};
[INFO] [stdout]   |                     ^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused `std::result::Result` that must be used
[INFO] [stdout]   --> src/main.rs:25:9
[INFO] [stdout]    |
[INFO] [stdout] 25 |         stdout_lock.write(char.to_string().as_bytes());
[INFO] [stdout]    |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(unused_must_use)]` on by default
[INFO] [stdout]    = note: this `Result` may be an `Err` variant, which should be handled
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 3 warnings emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused `std::result::Result` that must be used
[INFO] [stdout]   --> src/main.rs:25:9
[INFO] [stdout]    |
[INFO] [stdout] 25 |         stdout_lock.write(char.to_string().as_bytes());
[INFO] [stdout]    |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(unused_must_use)]` on by default
[INFO] [stdout]    = note: this `Result` may be an `Err` variant, which should be handled
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 3 warnings emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]     Finished dev [unoptimized + debuginfo] target(s) in 1.72s
[INFO] running `Command { std: "docker" "inspect" "08c9493a43d5a7b2699c4314023ca9b5b5e3215b86dcd33c1fbda00e4897ccec", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "08c9493a43d5a7b2699c4314023ca9b5b5e3215b86dcd33c1fbda00e4897ccec", kill_on_drop: false }`
[INFO] [stdout] 08c9493a43d5a7b2699c4314023ca9b5b5e3215b86dcd33c1fbda00e4897ccec