[INFO] fetching crate tail 0.3.0...
[INFO] testing tail-0.3.0 against beta-2021-08-01 for beta-1.55-1
[INFO] extracting crate tail 0.3.0 into /workspace/builds/worker-20/source
[INFO] validating manifest of crates.io crate tail 0.3.0 on toolchain beta-2021-08-01
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+beta-2021-08-01" "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-20/source/Cargo.toml
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+beta-2021-08-01" "generate-lockfile" "--manifest-path" "Cargo.toml" "-Zno-index-update", kill_on_drop: false }`
[INFO] [stderr]     Blocking waiting for file lock on package cache
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+beta-2021-08-01" "fetch" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] [stderr]  Downloading crates ...
[INFO] [stderr]   Downloaded inotify v0.5.1
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-20/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-20/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@sha256:34b6a614d2c27851fe6cbf88fbd1137609cefab8b10d0615aaeb6fd47975d74e" "/opt/rustwide/cargo-home/bin/cargo" "+beta-2021-08-01" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] 0a953bc2b3858f352b363d3f4c177e81c02712898d3aaa406ab7ee18926e53f7
[INFO] running `Command { std: "docker" "start" "-a" "0a953bc2b3858f352b363d3f4c177e81c02712898d3aaa406ab7ee18926e53f7", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "0a953bc2b3858f352b363d3f4c177e81c02712898d3aaa406ab7ee18926e53f7", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "0a953bc2b3858f352b363d3f4c177e81c02712898d3aaa406ab7ee18926e53f7", kill_on_drop: false }`
[INFO] [stdout] 0a953bc2b3858f352b363d3f4c177e81c02712898d3aaa406ab7ee18926e53f7
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-20/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-20/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=warn" "-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@sha256:34b6a614d2c27851fe6cbf88fbd1137609cefab8b10d0615aaeb6fd47975d74e" "/opt/rustwide/cargo-home/bin/cargo" "+beta-2021-08-01" "build" "--frozen" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] 6c07fe3ec86c9aef3191dc4458efd689eb9882d6012f6b3df95b80afd4c249d7
[INFO] running `Command { std: "docker" "start" "-a" "6c07fe3ec86c9aef3191dc4458efd689eb9882d6012f6b3df95b80afd4c249d7", kill_on_drop: false }`
[INFO] [stderr]    Compiling futures v0.1.31
[INFO] [stderr]    Compiling getopts v0.2.21
[INFO] [stderr]    Compiling inotify-sys v0.1.5
[INFO] [stderr]    Compiling inotify v0.5.1
[INFO] [stderr]    Compiling 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_panics)]` on by default
[INFO] [stdout]    = note: this usage of panic!() is deprecated; it will be a hard error in Rust 2021
[INFO] [stdout]    = note: for more information, see <https://doc.rust-lang.org/nightly/edition-guide/rust-2021/panic-macro-consistency.html>
[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 5.96s
[INFO] running `Command { std: "docker" "inspect" "6c07fe3ec86c9aef3191dc4458efd689eb9882d6012f6b3df95b80afd4c249d7", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "6c07fe3ec86c9aef3191dc4458efd689eb9882d6012f6b3df95b80afd4c249d7", kill_on_drop: false }`
[INFO] [stdout] 6c07fe3ec86c9aef3191dc4458efd689eb9882d6012f6b3df95b80afd4c249d7
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-20/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-20/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=warn" "-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@sha256:34b6a614d2c27851fe6cbf88fbd1137609cefab8b10d0615aaeb6fd47975d74e" "/opt/rustwide/cargo-home/bin/cargo" "+beta-2021-08-01" "test" "--frozen" "--no-run" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] 6a2eb9f094ceef306d4f9b19c9535d84c68450402bc0ac11f55b42f466264cc5
[INFO] running `Command { std: "docker" "start" "-a" "6a2eb9f094ceef306d4f9b19c9535d84c68450402bc0ac11f55b42f466264cc5", kill_on_drop: false }`
[INFO] [stderr]     Blocking waiting for file lock on package cache
[INFO] [stderr]    Compiling 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_panics)]` on by default
[INFO] [stdout]    = note: this usage of panic!() is deprecated; it will be a hard error in Rust 2021
[INFO] [stdout]    = note: for more information, see <https://doc.rust-lang.org/nightly/edition-guide/rust-2021/panic-macro-consistency.html>
[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 test [unoptimized + debuginfo] target(s) in 0.83s
[INFO] running `Command { std: "docker" "inspect" "6a2eb9f094ceef306d4f9b19c9535d84c68450402bc0ac11f55b42f466264cc5", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "6a2eb9f094ceef306d4f9b19c9535d84c68450402bc0ac11f55b42f466264cc5", kill_on_drop: false }`
[INFO] [stdout] 6a2eb9f094ceef306d4f9b19c9535d84c68450402bc0ac11f55b42f466264cc5
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-20/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-20/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=warn" "-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@sha256:34b6a614d2c27851fe6cbf88fbd1137609cefab8b10d0615aaeb6fd47975d74e" "/opt/rustwide/cargo-home/bin/cargo" "+beta-2021-08-01" "test" "--frozen", kill_on_drop: false }`
[INFO] [stdout] 14f166f7ee9f4a640fda864afb1e6b52d276288c3eff338d9c494889631f837d
[INFO] running `Command { std: "docker" "start" "-a" "14f166f7ee9f4a640fda864afb1e6b52d276288c3eff338d9c494889631f837d", kill_on_drop: false }`
[INFO] [stderr] warning: variable does not need to be mutable
[INFO] [stderr]   --> src/main.rs:88:13
[INFO] [stderr]    |
[INFO] [stderr] 88 |         let mut wd = watcher.add_watch(Path::new(&file_name), WatchMask::MODIFY)
[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]   --> src/main.rs:90:13
[INFO] [stderr]    |
[INFO] [stderr] 90 |         let mut fd = File::open(&file_name)
[INFO] [stderr]    |             ----^^
[INFO] [stderr]    |             |
[INFO] [stderr]    |             help: remove this `mut`
[INFO] [stderr] 
[INFO] [stderr] warning: panic message is not a string literal
[INFO] [stderr]   --> src/main.rs:64:28
[INFO] [stderr]    |
[INFO] [stderr] 64 |         Err(f) => { panic!(f.to_string()) }
[INFO] [stderr]    |                            ^^^^^^^^^^^^^
[INFO] [stderr]    |
[INFO] [stderr]    = note: `#[warn(non_fmt_panics)]` on by default
[INFO] [stderr]    = note: this usage of panic!() is deprecated; it will be a hard error in Rust 2021
[INFO] [stderr]    = note: for more information, see <https://doc.rust-lang.org/nightly/edition-guide/rust-2021/panic-macro-consistency.html>
[INFO] [stderr] help: add a "{}" format string to Display the message
[INFO] [stderr]    |
[INFO] [stderr] 64 |         Err(f) => { panic!("{}", f.to_string()) }
[INFO] [stderr]    |                            ^^^^^
[INFO] [stderr] help: or use std::panic::panic_any instead
[INFO] [stderr]    |
[INFO] [stderr] 64 |         Err(f) => { std::panic::panic_any(f.to_string()) }
[INFO] [stderr]    |                     ^^^^^^^^^^^^^^^^^^^^^
[INFO] [stderr] 
[INFO] [stderr] warning: `tail` (bin "tail" test) generated 3 warnings
[INFO] [stderr]     Finished test [unoptimized + debuginfo] target(s) in 0.19s
[INFO] [stderr]      Running unittests (/opt/rustwide/target/debug/deps/tail-0c38ea2d1efda649)
[INFO] [stdout] 
[INFO] [stdout] running 0 tests
[INFO] [stdout] 
[INFO] [stdout] test result: ok. 0 passed; 0 failed; 0 ignored; 0 measured; 0 filtered out; finished in 0.00s
[INFO] [stdout] 
[INFO] [stderr]      Running unittests (/opt/rustwide/target/debug/deps/tail-e9dde7cf36ed17ce)
[INFO] [stdout] 
[INFO] [stderr]    Doc-tests tail
[INFO] [stdout] running 0 tests
[INFO] [stdout] 
[INFO] [stdout] test result: ok. 0 passed; 0 failed; 0 ignored; 0 measured; 0 filtered out; finished in 0.00s
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] running 1 test
[INFO] [stdout] test src/lib.rs - BackwardsReader (line 23) ... FAILED
[INFO] [stdout] 
[INFO] [stdout] failures:
[INFO] [stdout] 
[INFO] [stdout] ---- src/lib.rs - BackwardsReader (line 23) stdout ----
[INFO] [stdout] error[E0433]: failed to resolve: use of undeclared type `BackwardsReader`
[INFO] [stdout]  --> src/lib.rs:25:18
[INFO] [stdout]   |
[INFO] [stdout] 4 | let mut reader = BackwardsReader::new(10, &mut writer);
[INFO] [stdout]   |                  ^^^^^^^^^^^^^^^ use of undeclared type `BackwardsReader`
[INFO] [stdout] 
[INFO] [stdout] error[E0433]: failed to resolve: use of undeclared type `BufWriter`
[INFO] [stdout]  --> src/lib.rs:24:18
[INFO] [stdout]   |
[INFO] [stdout] 3 | let mut writer = BufWriter::new(std::io::stdout());
[INFO] [stdout]   |                  ^^^^^^^^^ not found in this scope
[INFO] [stdout]   |
[INFO] [stdout] help: consider importing this struct
[INFO] [stdout]   |
[INFO] [stdout] 2 | use std::io::BufWriter;
[INFO] [stdout]   |
[INFO] [stdout] 
[INFO] [stdout] error: aborting due to 2 previous errors
[INFO] [stdout] 
[INFO] [stdout] For more information about this error, try `rustc --explain E0433`.
[INFO] [stdout] Couldn't compile the test.
[INFO] [stdout] 
[INFO] [stdout] failures:
[INFO] [stdout]     src/lib.rs - BackwardsReader (line 23)
[INFO] [stdout] 
[INFO] [stdout] test result: FAILED. 0 passed; 1 failed; 0 ignored; 0 measured; 0 filtered out; finished in 0.19s
[INFO] [stdout] 
[INFO] [stderr] error: test failed, to rerun pass '--doc'
[INFO] running `Command { std: "docker" "inspect" "14f166f7ee9f4a640fda864afb1e6b52d276288c3eff338d9c494889631f837d", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "14f166f7ee9f4a640fda864afb1e6b52d276288c3eff338d9c494889631f837d", kill_on_drop: false }`
[INFO] [stdout] 14f166f7ee9f4a640fda864afb1e6b52d276288c3eff338d9c494889631f837d
