[INFO] fetching crate maybe-single 0.12.0...
[INFO] testing maybe-single-0.12.0 against try#eafdee2dfae8c2233b74f98b123308be7ccefcc6 for pr-79296
[INFO] extracting crate maybe-single 0.12.0 into /workspace/builds/worker-2/source
[INFO] validating manifest of crates.io crate maybe-single 0.12.0 on toolchain eafdee2dfae8c2233b74f98b123308be7ccefcc6
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+eafdee2dfae8c2233b74f98b123308be7ccefcc6" "read-manifest" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] started tweaking crates.io crate maybe-single 0.12.0
[INFO] finished tweaking crates.io crate maybe-single 0.12.0
[INFO] tweaked toml for crates.io crate maybe-single 0.12.0 written to /workspace/builds/worker-2/source/Cargo.toml
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+eafdee2dfae8c2233b74f98b123308be7ccefcc6" "generate-lockfile" "--manifest-path" "Cargo.toml" "-Zno-index-update", kill_on_drop: false }`
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+eafdee2dfae8c2233b74f98b123308be7ccefcc6" "fetch" "--locked" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-2/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-2/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" "rustops/crates-build-env@sha256:6eabd152ff4036248d66efda456a36cb33d24b7291b33f25f75140726c88da35" "/opt/rustwide/cargo-home/bin/cargo" "+eafdee2dfae8c2233b74f98b123308be7ccefcc6" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] 78de02bbcd4d8d8dfb2f070fe951958597ce0cf6bd7a410d5c39413be37fc2d0
[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" "78de02bbcd4d8d8dfb2f070fe951958597ce0cf6bd7a410d5c39413be37fc2d0", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "78de02bbcd4d8d8dfb2f070fe951958597ce0cf6bd7a410d5c39413be37fc2d0", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "78de02bbcd4d8d8dfb2f070fe951958597ce0cf6bd7a410d5c39413be37fc2d0", kill_on_drop: false }`
[INFO] [stdout] 78de02bbcd4d8d8dfb2f070fe951958597ce0cf6bd7a410d5c39413be37fc2d0
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-2/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-2/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" "rustops/crates-build-env@sha256:6eabd152ff4036248d66efda456a36cb33d24b7291b33f25f75140726c88da35" "/opt/rustwide/cargo-home/bin/cargo" "+eafdee2dfae8c2233b74f98b123308be7ccefcc6" "build" "--frozen" "--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] e52fa1e5eedf7b772efa332bfd9d3fdcd4404786e4676b84fb7fc6664ed638b0
[INFO] running `Command { std: "docker" "start" "-a" "e52fa1e5eedf7b772efa332bfd9d3fdcd4404786e4676b84fb7fc6664ed638b0", kill_on_drop: false }`
[INFO] [stderr]    Compiling libc v0.2.80
[INFO] [stderr]    Compiling smallvec v1.5.0
[INFO] [stderr]    Compiling parking_lot_core v0.7.2
[INFO] [stderr]    Compiling parking_lot v0.10.2
[INFO] [stderr]    Compiling maybe-single v0.12.0 (/opt/rustwide/workdir)
[INFO] [stdout] warning: unused import: `std::ops::Deref`
[INFO] [stdout]  --> src/nio.rs:1:5
[INFO] [stdout]   |
[INFO] [stdout] 1 | use std::ops::Deref;
[INFO] [stdout]   |     ^^^^^^^^^^^^^^^
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(unused_imports)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused imports: `RwLockReadGuard`, `RwLockWriteGuard`
[INFO] [stdout]  --> src/nio.rs:6:34
[INFO] [stdout]   |
[INFO] [stdout] 6 | use parking_lot::{Mutex, RwLock, RwLockReadGuard, RwLockWriteGuard};
[INFO] [stdout]   |                                  ^^^^^^^^^^^^^^^  ^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: field is never read: `read_lock`
[INFO] [stdout]   --> src/lib.rs:77:5
[INFO] [stdout]    |
[INFO] [stdout] 77 |     read_lock: Option<RwLockReadGuard<'a, ()>>,
[INFO] [stdout]    |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(dead_code)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: field is never read: `write_lock`
[INFO] [stdout]   --> src/lib.rs:78:5
[INFO] [stdout]    |
[INFO] [stdout] 78 |     write_lock: Option<RwLockWriteGuard<'a, ()>>,
[INFO] [stdout]    |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 4 warnings emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]     Finished dev [unoptimized + debuginfo] target(s) in 5.07s
[INFO] running `Command { std: "docker" "inspect" "e52fa1e5eedf7b772efa332bfd9d3fdcd4404786e4676b84fb7fc6664ed638b0", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "e52fa1e5eedf7b772efa332bfd9d3fdcd4404786e4676b84fb7fc6664ed638b0", kill_on_drop: false }`
[INFO] [stdout] e52fa1e5eedf7b772efa332bfd9d3fdcd4404786e4676b84fb7fc6664ed638b0
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-2/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-2/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" "rustops/crates-build-env@sha256:6eabd152ff4036248d66efda456a36cb33d24b7291b33f25f75140726c88da35" "/opt/rustwide/cargo-home/bin/cargo" "+eafdee2dfae8c2233b74f98b123308be7ccefcc6" "test" "--frozen" "--no-run" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] 89d58bdaa91a6877963a05d7b2fa1eb989a8a0a5cf673d8abb912894667575f9
[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" "89d58bdaa91a6877963a05d7b2fa1eb989a8a0a5cf673d8abb912894667575f9", kill_on_drop: false }`
[INFO] [stderr]    Compiling syn v1.0.52
[INFO] [stderr]    Compiling futures-core v0.3.8
[INFO] [stderr]    Compiling iovec v0.1.4
[INFO] [stderr]    Compiling net2 v0.2.36
[INFO] [stderr]    Compiling getrandom v0.1.15
[INFO] [stderr]    Compiling num_cpus v1.13.0
[INFO] [stderr]    Compiling signal-hook-registry v1.2.2
[INFO] [stdout] warning: unused import: `std::ops::Deref`
[INFO] [stdout]  --> src/nio.rs:1:5
[INFO] [stdout]   |
[INFO] [stdout] 1 | use std::ops::Deref;
[INFO] [stdout]   |     ^^^^^^^^^^^^^^^
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(unused_imports)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused imports: `RwLockReadGuard`, `RwLockWriteGuard`
[INFO] [stdout]  --> src/nio.rs:6:34
[INFO] [stdout]   |
[INFO] [stdout] 6 | use parking_lot::{Mutex, RwLock, RwLockReadGuard, RwLockWriteGuard};
[INFO] [stdout]   |                                  ^^^^^^^^^^^^^^^  ^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: field is never read: `read_lock`
[INFO] [stdout]   --> src/lib.rs:77:5
[INFO] [stdout]    |
[INFO] [stdout] 77 |     read_lock: Option<RwLockReadGuard<'a, ()>>,
[INFO] [stdout]    |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(dead_code)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: field is never read: `write_lock`
[INFO] [stdout]   --> src/lib.rs:78:5
[INFO] [stdout]    |
[INFO] [stdout] 78 |     write_lock: Option<RwLockWriteGuard<'a, ()>>,
[INFO] [stdout]    |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 4 warnings emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]    Compiling rand_core v0.5.1
[INFO] [stderr]    Compiling mio v0.6.22
[INFO] [stderr]    Compiling rand_chacha v0.2.2
[INFO] [stderr]    Compiling rand v0.7.3
[INFO] [stderr]    Compiling mio-uds v0.6.8
[INFO] [stderr]    Compiling tokio-macros v0.2.6
[INFO] [stderr]    Compiling tokio v0.2.23
[INFO] [stderr]    Compiling maybe-single v0.12.0 (/opt/rustwide/workdir)
[INFO] [stdout] warning: unused import: `std::ops::Deref`
[INFO] [stdout]  --> src/nio.rs:1:5
[INFO] [stdout]   |
[INFO] [stdout] 1 | use std::ops::Deref;
[INFO] [stdout]   |     ^^^^^^^^^^^^^^^
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(unused_imports)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused imports: `RwLockReadGuard`, `RwLockWriteGuard`
[INFO] [stdout]  --> src/nio.rs:6:34
[INFO] [stdout]   |
[INFO] [stdout] 6 | use parking_lot::{Mutex, RwLock, RwLockReadGuard, RwLockWriteGuard};
[INFO] [stdout]   |                                  ^^^^^^^^^^^^^^^  ^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused imports: `Rng`, `thread_rng`
[INFO] [stdout]   --> src/nio.rs:87:16
[INFO] [stdout]    |
[INFO] [stdout] 87 |     use rand::{thread_rng, Rng};
[INFO] [stdout]    |                ^^^^^^^^^^  ^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused import: `std::thread::sleep`
[INFO] [stdout]   --> src/nio.rs:88:9
[INFO] [stdout]    |
[INFO] [stdout] 88 |     use std::thread::sleep;
[INFO] [stdout]    |         ^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused import: `std::time::Duration`
[INFO] [stdout]   --> src/nio.rs:89:9
[INFO] [stdout]    |
[INFO] [stdout] 89 |     use std::time::Duration;
[INFO] [stdout]    |         ^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused import: `tokio::time::Instant`
[INFO] [stdout]   --> src/nio.rs:90:9
[INFO] [stdout]    |
[INFO] [stdout] 90 |     use tokio::time::Instant;
[INFO] [stdout]    |         ^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused import: `std::future::Future`
[INFO] [stdout]    --> src/lib.rs:119:9
[INFO] [stdout]     |
[INFO] [stdout] 119 |     use std::future::Future;
[INFO] [stdout]     |         ^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused import: `std::pin::Pin`
[INFO] [stdout]    --> src/lib.rs:120:9
[INFO] [stdout]     |
[INFO] [stdout] 120 |     use std::pin::Pin;
[INFO] [stdout]     |         ^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: field is never read: `read_lock`
[INFO] [stdout]   --> src/lib.rs:77:5
[INFO] [stdout]    |
[INFO] [stdout] 77 |     read_lock: Option<RwLockReadGuard<'a, ()>>,
[INFO] [stdout]    |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(dead_code)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: field is never read: `write_lock`
[INFO] [stdout]   --> src/lib.rs:78:5
[INFO] [stdout]    |
[INFO] [stdout] 78 |     write_lock: Option<RwLockWriteGuard<'a, ()>>,
[INFO] [stdout]    |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 10 warnings emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]     Finished test [unoptimized + debuginfo] target(s) in 41.56s
[INFO] running `Command { std: "docker" "inspect" "89d58bdaa91a6877963a05d7b2fa1eb989a8a0a5cf673d8abb912894667575f9", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "89d58bdaa91a6877963a05d7b2fa1eb989a8a0a5cf673d8abb912894667575f9", kill_on_drop: false }`
[INFO] [stdout] 89d58bdaa91a6877963a05d7b2fa1eb989a8a0a5cf673d8abb912894667575f9
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-2/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-2/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" "rustops/crates-build-env@sha256:6eabd152ff4036248d66efda456a36cb33d24b7291b33f25f75140726c88da35" "/opt/rustwide/cargo-home/bin/cargo" "+eafdee2dfae8c2233b74f98b123308be7ccefcc6" "test" "--frozen", kill_on_drop: false }`
[INFO] [stdout] a7fd7cf7a24212062b76d3ce7ea78cd45cc59ccae684baf2b17695e678636059
[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" "a7fd7cf7a24212062b76d3ce7ea78cd45cc59ccae684baf2b17695e678636059", kill_on_drop: false }`
[INFO] [stdout] 
[INFO] [stderr] warning: unused import: `std::ops::Deref`
[INFO] [stdout] running 4 tests
[INFO] [stderr]  --> src/nio.rs:1:5
[INFO] [stdout] test nio::test::maybe_should_be_sync ... ok
[INFO] [stderr]   |
[INFO] [stdout] test nio::test::maybe_should_be_send ... ok
[INFO] [stderr] 1 | use std::ops::Deref;
[INFO] [stderr]   |     ^^^^^^^^^^^^^^^
[INFO] [stderr]   |
[INFO] [stderr]   = note: `#[warn(unused_imports)]` on by default
[INFO] [stderr] 
[INFO] [stderr] warning: unused imports: `RwLockReadGuard`, `RwLockWriteGuard`
[INFO] [stderr]  --> src/nio.rs:6:34
[INFO] [stderr]   |
[INFO] [stderr] 6 | use parking_lot::{Mutex, RwLock, RwLockReadGuard, RwLockWriteGuard};
[INFO] [stderr]   |                                  ^^^^^^^^^^^^^^^  ^^^^^^^^^^^^^^^^
[INFO] [stderr] 
[INFO] [stderr] warning: field is never read: `read_lock`
[INFO] [stderr]   --> src/lib.rs:77:5
[INFO] [stderr]    |
[INFO] [stderr] 77 |     read_lock: Option<RwLockReadGuard<'a, ()>>,
[INFO] [stderr]    |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stderr]    |
[INFO] [stderr]    = note: `#[warn(dead_code)]` on by default
[INFO] [stderr] 
[INFO] [stderr] warning: field is never read: `write_lock`
[INFO] [stderr]   --> src/lib.rs:78:5
[INFO] [stderr]    |
[INFO] [stderr] 78 |     write_lock: Option<RwLockWriteGuard<'a, ()>>,
[INFO] [stderr]    |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stderr] 
[INFO] [stderr] warning: 4 warnings emitted
[INFO] [stderr] 
[INFO] [stderr] warning: unused import: `std::ops::Deref`
[INFO] [stderr]  --> src/nio.rs:1:5
[INFO] [stderr]   |
[INFO] [stderr] 1 | use std::ops::Deref;
[INFO] [stderr]   |     ^^^^^^^^^^^^^^^
[INFO] [stderr]   |
[INFO] [stderr]   = note: `#[warn(unused_imports)]` on by default
[INFO] [stderr] 
[INFO] [stderr] warning: unused imports: `RwLockReadGuard`, `RwLockWriteGuard`
[INFO] [stderr]  --> src/nio.rs:6:34
[INFO] [stderr]   |
[INFO] [stderr] 6 | use parking_lot::{Mutex, RwLock, RwLockReadGuard, RwLockWriteGuard};
[INFO] [stderr]   |                                  ^^^^^^^^^^^^^^^  ^^^^^^^^^^^^^^^^
[INFO] [stderr] 
[INFO] [stderr] warning: unused imports: `Rng`, `thread_rng`
[INFO] [stderr]   --> src/nio.rs:87:16
[INFO] [stderr]    |
[INFO] [stderr] 87 |     use rand::{thread_rng, Rng};
[INFO] [stderr]    |                ^^^^^^^^^^  ^^^
[INFO] [stderr] 
[INFO] [stderr] warning: unused import: `std::thread::sleep`
[INFO] [stderr]   --> src/nio.rs:88:9
[INFO] [stderr]    |
[INFO] [stderr] 88 |     use std::thread::sleep;
[INFO] [stderr]    |         ^^^^^^^^^^^^^^^^^^
[INFO] [stderr] 
[INFO] [stderr] warning: unused import: `std::time::Duration`
[INFO] [stderr]   --> src/nio.rs:89:9
[INFO] [stderr]    |
[INFO] [stderr] 89 |     use std::time::Duration;
[INFO] [stderr]    |         ^^^^^^^^^^^^^^^^^^^
[INFO] [stderr] 
[INFO] [stderr] warning: unused import: `tokio::time::Instant`
[INFO] [stderr]   --> src/nio.rs:90:9
[INFO] [stderr]    |
[INFO] [stderr] 90 |     use tokio::time::Instant;
[INFO] [stderr]    |         ^^^^^^^^^^^^^^^^^^^^
[INFO] [stderr] 
[INFO] [stderr] warning: unused import: `std::future::Future`
[INFO] [stderr]    --> src/lib.rs:119:9
[INFO] [stderr]     |
[INFO] [stderr] 119 |     use std::future::Future;
[INFO] [stderr]     |         ^^^^^^^^^^^^^^^^^^^
[INFO] [stderr] 
[INFO] [stderr] warning: unused import: `std::pin::Pin`
[INFO] [stderr]    --> src/lib.rs:120:9
[INFO] [stderr]     |
[INFO] [stderr] 120 |     use std::pin::Pin;
[INFO] [stderr]     |         ^^^^^^^^^^^^^
[INFO] [stderr] 
[INFO] [stderr] warning: field is never read: `read_lock`
[INFO] [stderr]   --> src/lib.rs:77:5
[INFO] [stderr]    |
[INFO] [stderr] 77 |     read_lock: Option<RwLockReadGuard<'a, ()>>,
[INFO] [stderr]    |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stderr]    |
[INFO] [stderr]    = note: `#[warn(dead_code)]` on by default
[INFO] [stderr] 
[INFO] [stderr] warning: field is never read: `write_lock`
[INFO] [stderr]   --> src/lib.rs:78:5
[INFO] [stderr]    |
[INFO] [stderr] 78 |     write_lock: Option<RwLockWriteGuard<'a, ()>>,
[INFO] [stderr]    |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stderr] 
[INFO] [stderr] warning: 10 warnings emitted
[INFO] [stderr] 
[INFO] [stderr]     Finished test [unoptimized + debuginfo] target(s) in 0.07s
[INFO] [stderr]      Running /opt/rustwide/target/debug/deps/maybe_single-695a53297ef7898b
[INFO] [stdout] test test::should_execute_in_parallel ... ok
[INFO] [stderr]    Doc-tests maybe-single
[INFO] [stdout] test test::should_execute_serially ... ok
[INFO] [stdout] 
[INFO] [stdout] test result: ok. 4 passed; 0 failed; 0 ignored; 0 measured; 0 filtered out
[INFO] [stdout] 
[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
[INFO] [stdout] 
[INFO] running `Command { std: "docker" "inspect" "a7fd7cf7a24212062b76d3ce7ea78cd45cc59ccae684baf2b17695e678636059", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "a7fd7cf7a24212062b76d3ce7ea78cd45cc59ccae684baf2b17695e678636059", kill_on_drop: false }`
[INFO] [stdout] a7fd7cf7a24212062b76d3ce7ea78cd45cc59ccae684baf2b17695e678636059