[INFO] fetching crate tail 0.3.0...
[INFO] checking tail-0.3.0 against master#836c31742687ba4e2f857b5b698e1e9e6b67619c for pr-81789
[INFO] extracting crate tail 0.3.0 into /workspace/builds/worker-14/source
[INFO] validating manifest of crates.io crate tail 0.3.0 on toolchain 836c31742687ba4e2f857b5b698e1e9e6b67619c
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+836c31742687ba4e2f857b5b698e1e9e6b67619c" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }`
[INFO] started tweaking crates.io crate tail 0.3.0
[INFO] finished tweaking crates.io crate tail 0.3.0
[INFO] tweaked toml for crates.io crate tail 0.3.0 written to /workspace/builds/worker-14/source/Cargo.toml
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+836c31742687ba4e2f857b5b698e1e9e6b67619c" "generate-lockfile" "--manifest-path" "Cargo.toml" "-Zno-index-update", kill_on_drop: false }`
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+836c31742687ba4e2f857b5b698e1e9e6b67619c" "fetch" "--locked" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-14/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-14/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@sha256:20528e8c29e4536546f0102ce88568b16ea7538393a33fcca951030f7af10457" "/opt/rustwide/cargo-home/bin/cargo" "+836c31742687ba4e2f857b5b698e1e9e6b67619c" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] 0629fee471c3109417cedc44585f7312f2097bc1d6aa38128788bdaa2599fd8e
[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" "0629fee471c3109417cedc44585f7312f2097bc1d6aa38128788bdaa2599fd8e", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "0629fee471c3109417cedc44585f7312f2097bc1d6aa38128788bdaa2599fd8e", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "0629fee471c3109417cedc44585f7312f2097bc1d6aa38128788bdaa2599fd8e", kill_on_drop: false }`
[INFO] [stdout] 0629fee471c3109417cedc44585f7312f2097bc1d6aa38128788bdaa2599fd8e
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-14/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-14/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" "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@sha256:20528e8c29e4536546f0102ce88568b16ea7538393a33fcca951030f7af10457" "/opt/rustwide/cargo-home/bin/cargo" "+836c31742687ba4e2f857b5b698e1e9e6b67619c" "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] 5050eec6095d4d54884a4c68aa152e75ef610794f72e233a4f594b4ab8ce203a
[INFO] running `Command { std: "docker" "start" "-a" "5050eec6095d4d54884a4c68aa152e75ef610794f72e233a4f594b4ab8ce203a", kill_on_drop: false }`
[INFO] [stderr]    Compiling libc v0.2.93
[INFO] [stderr]     Checking inotify-sys v0.1.5
[INFO] [stderr]     Checking inotify v0.5.1
[INFO] [stderr]     Checking tail v0.3.0 (/opt/rustwide/workdir)
[INFO] [stdout] warning: variable does not need to be mutable
[INFO] [stdout]   --> src/main.rs:88:13
[INFO] [stdout]    |
[INFO] [stdout] 88 |         let mut wd = watcher.add_watch(Path::new(&file_name), WatchMask::MODIFY)
[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/main.rs:90:13
[INFO] [stdout]    |
[INFO] [stdout] 90 |         let mut fd = File::open(&file_name)
[INFO] [stdout]    |             ----^^
[INFO] [stdout]    |             |
[INFO] [stdout]    |             help: remove this `mut`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: panic message is not a string literal
[INFO] [stdout]   --> src/main.rs:64:28
[INFO] [stdout]    |
[INFO] [stdout] 64 |         Err(f) => { panic!(f.to_string()) }
[INFO] [stdout]    |                            ^^^^^^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(non_fmt_panic)]` on by default
[INFO] [stdout]    = note: this is no longer accepted in Rust 2021
[INFO] [stdout] help: add a "{}" format string to Display the message
[INFO] [stdout]    |
[INFO] [stdout] 64 |         Err(f) => { panic!("{}", f.to_string()) }
[INFO] [stdout]    |                            ^^^^^
[INFO] [stdout] help: or use std::panic::panic_any instead
[INFO] [stdout]    |
[INFO] [stdout] 64 |         Err(f) => { std::panic::panic_any(f.to_string()) }
[INFO] [stdout]    |                     ^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: variable does not need to be mutable
[INFO] [stdout]   --> src/main.rs:88:13
[INFO] [stdout]    |
[INFO] [stdout] 88 |         let mut wd = watcher.add_watch(Path::new(&file_name), WatchMask::MODIFY)
[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/main.rs:90:13
[INFO] [stdout]    |
[INFO] [stdout] 90 |         let mut fd = File::open(&file_name)
[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: panic message is not a string literal
[INFO] [stdout]   --> src/main.rs:64:28
[INFO] [stdout]    |
[INFO] [stdout] 64 |         Err(f) => { panic!(f.to_string()) }
[INFO] [stdout]    |                            ^^^^^^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(non_fmt_panic)]` on by default
[INFO] [stdout]    = note: this is no longer accepted in Rust 2021
[INFO] [stdout] help: add a "{}" format string to Display the message
[INFO] [stdout]    |
[INFO] [stdout] 64 |         Err(f) => { panic!("{}", f.to_string()) }
[INFO] [stdout]    |                            ^^^^^
[INFO] [stdout] help: or use std::panic::panic_any instead
[INFO] [stdout]    |
[INFO] [stdout] 64 |         Err(f) => { std::panic::panic_any(f.to_string()) }
[INFO] [stdout]    |                     ^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 3 warnings emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]     Finished dev [unoptimized + debuginfo] target(s) in 5.01s
[INFO] running `Command { std: "docker" "inspect" "5050eec6095d4d54884a4c68aa152e75ef610794f72e233a4f594b4ab8ce203a", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "5050eec6095d4d54884a4c68aa152e75ef610794f72e233a4f594b4ab8ce203a", kill_on_drop: false }`
[INFO] [stdout] 5050eec6095d4d54884a4c68aa152e75ef610794f72e233a4f594b4ab8ce203a