[INFO] fetching crate mioco 0.8.1...
[INFO] testing mioco-0.8.1 against 1.69.0 for beta-1.70-1
[INFO] extracting crate mioco 0.8.1 into /workspace/builds/worker-3-tc1/source
[INFO] validating manifest of crates.io crate mioco 0.8.1 on toolchain 1.69.0
[INFO] running `Command { std: CARGO_HOME="/workspace/cargo-home" RUSTUP_HOME="/workspace/rustup-home" "/workspace/cargo-home/bin/cargo" "+1.69.0" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }`
[INFO] started tweaking crates.io crate mioco 0.8.1
[INFO] finished tweaking crates.io crate mioco 0.8.1
[INFO] tweaked toml for crates.io crate mioco 0.8.1 written to /workspace/builds/worker-3-tc1/source/Cargo.toml
[INFO] running `Command { std: CARGO_HOME="/workspace/cargo-home" RUSTUP_HOME="/workspace/rustup-home" __CARGO_TEST_CHANNEL_OVERRIDE_DO_NOT_USE_THIS="nightly" "/workspace/cargo-home/bin/cargo" "+1.69.0" "generate-lockfile" "--manifest-path" "Cargo.toml" "-Zno-index-update", kill_on_drop: false }`
[INFO] running `Command { std: CARGO_HOME="/workspace/cargo-home" RUSTUP_HOME="/workspace/rustup-home" "/workspace/cargo-home/bin/cargo" "+1.69.0" "fetch" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] [stderr]  Downloading crates ...
[INFO] [stderr]   Downloaded owning_ref v0.2.4
[INFO] [stderr]   Downloaded mio v0.5.1
[INFO] [stderr]   Downloaded env_logger v0.3.5
[INFO] [stderr]   Downloaded bytes v0.3.0
[INFO] [stderr]   Downloaded slab v0.1.3
[INFO] [stderr]   Downloaded slab v0.2.0
[INFO] [stderr]   Downloaded toml v0.1.30
[INFO] [stderr]   Downloaded quine-mc_cluskey v0.2.4
[INFO] [stderr]   Downloaded semver v0.2.3
[INFO] [stderr]   Downloaded context v1.0.1
[INFO] [stderr]   Downloaded clippy_lints v0.0.85
[INFO] [stderr]   Downloaded clippy v0.0.85
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-3-tc1/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-3-tc1/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@sha256:5ff2268d62e97bff2cde7d5815dd6ed5b47097566f13b8d0ca110b04b60e07ed" "/opt/rustwide/cargo-home/bin/cargo" "+1.69.0" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] 7e4125d15276e3258187bea4f4dba27ab9d5e9ddd0e3e2461a33abf855568f21
[INFO] running `Command { std: "docker" "start" "-a" "7e4125d15276e3258187bea4f4dba27ab9d5e9ddd0e3e2461a33abf855568f21", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "7e4125d15276e3258187bea4f4dba27ab9d5e9ddd0e3e2461a33abf855568f21", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "7e4125d15276e3258187bea4f4dba27ab9d5e9ddd0e3e2461a33abf855568f21", kill_on_drop: false }`
[INFO] [stdout] 7e4125d15276e3258187bea4f4dba27ab9d5e9ddd0e3e2461a33abf855568f21
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-3-tc1/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-3-tc1/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" "RUSTDOCFLAGS=--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@sha256:5ff2268d62e97bff2cde7d5815dd6ed5b47097566f13b8d0ca110b04b60e07ed" "/opt/rustwide/cargo-home/bin/cargo" "+1.69.0" "build" "--frozen" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] 41ffd928b6b582a837b6cb9bfcb5380500a8f6cddd257ae443a034e6ff486b48
[INFO] running `Command { std: "docker" "start" "-a" "41ffd928b6b582a837b6cb9bfcb5380500a8f6cddd257ae443a034e6ff486b48", kill_on_drop: false }`
[INFO] [stderr]    Compiling libc v0.2.142
[INFO] [stderr]    Compiling winapi-build v0.1.1
[INFO] [stderr]    Compiling log v0.4.17
[INFO] [stderr]    Compiling cfg-if v0.1.10
[INFO] [stderr]    Compiling semver v0.1.20
[INFO] [stderr]    Compiling winapi v0.2.8
[INFO] [stderr]    Compiling bitflags v0.4.0
[INFO] [stderr]    Compiling cfg-if v1.0.0
[INFO] [stderr]    Compiling gcc v0.3.55
[INFO] [stderr]    Compiling bytes v0.3.0
[INFO] [stderr]    Compiling void v1.0.2
[INFO] [stderr]    Compiling slab v0.1.3
[INFO] [stderr]    Compiling slab v0.2.0
[INFO] [stderr]    Compiling spin v0.4.10
[INFO] [stderr]    Compiling owning_ref v0.2.4
[INFO] [stderr]    Compiling thread-scoped v1.0.2
[INFO] [stderr]    Compiling kernel32-sys v0.2.2
[INFO] [stderr]    Compiling ws2_32-sys v0.2.1
[INFO] [stderr]    Compiling rustc_version v0.1.7
[INFO] [stderr]    Compiling nix v0.6.0
[INFO] [stderr]    Compiling log v0.3.9
[INFO] [stderr]    Compiling context v1.0.1
[INFO] [stderr]    Compiling net2 v0.2.38
[INFO] [stderr]    Compiling nix v0.5.1
[INFO] [stderr]    Compiling time v0.1.45
[INFO] [stderr]    Compiling num_cpus v1.15.0
[INFO] [stderr]    Compiling miow v0.1.5
[INFO] [stderr]    Compiling mio v0.5.1
[INFO] [stderr]    Compiling mioco v0.8.1 (/opt/rustwide/workdir)
[INFO] [stdout] warning: use of deprecated macro `try`: use the `?` operator instead
[INFO] [stdout]    --> src/sync/mpsc.rs:246:13
[INFO] [stdout]     |
[INFO] [stdout] 246 |             try!(self.sender.send(t));
[INFO] [stdout]     |             ^^^
[INFO] [stdout]     |
[INFO] [stdout]     = note: `#[warn(deprecated)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: use of deprecated macro `try`: use the `?` operator instead
[INFO] [stdout]    --> src/sync/mpsc.rs:276:9
[INFO] [stdout]     |
[INFO] [stdout] 276 |         try!(self.sender.send(t));
[INFO] [stdout]     |         ^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: use of deprecated macro `try`: use the `?` operator instead
[INFO] [stdout]    --> src/unix.rs:122:36
[INFO] [stdout]     |
[INFO] [stdout] 122 |     let (raw_reader, raw_writer) = try!(mio_orig::unix::pipe());
[INFO] [stdout]     |                                    ^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused doc comment
[INFO] [stdout]   --> src/thread.rs:19:1
[INFO] [stdout]    |
[INFO] [stdout] 19 | / /// Current coroutine thread-local reference
[INFO] [stdout] 20 | | ///
[INFO] [stdout] 21 | | /// This reference is used to store a reference to a currently executing
[INFO] [stdout] 22 | | /// mioco coroutine.
[INFO] [stdout] 23 | | ///
[INFO] [stdout] 24 | | /// Should not be used directly, use `tl_current_coroutine()` instead.
[INFO] [stdout]    | |_---------------------------------------------------------------------^
[INFO] [stdout]    |   |
[INFO] [stdout]    |   rustdoc does not generate documentation for macro invocations
[INFO] [stdout]    |
[INFO] [stdout]    = help: to document an item produced by a macro, the macro must produce the documentation as part of its expansion
[INFO] [stdout]    = note: `#[warn(unused_doc_comments)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: trait objects without an explicit `dyn` are deprecated
[INFO] [stdout]    --> src/coroutine.rs:166:29
[INFO] [stdout]     |
[INFO] [stdout] 166 |     pub blocked_on: Vec<Box<RcEventSourceTrait + 'static>>,
[INFO] [stdout]     |                             ^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout]     |
[INFO] [stdout]     = warning: this is accepted in the current edition (Rust 2015) but is a hard error in Rust 2021!
[INFO] [stdout]     = note: for more information, see <https://doc.rust-lang.org/nightly/edition-guide/rust-2021/warnings-promoted-to-error.html>
[INFO] [stdout]     = note: `#[warn(bare_trait_objects)]` on by default
[INFO] [stdout] help: use `dyn`
[INFO] [stdout]     |
[INFO] [stdout] 166 |     pub blocked_on: Vec<Box<dyn RcEventSourceTrait + 'static>>,
[INFO] [stdout]     |                             +++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: trait objects without an explicit `dyn` are deprecated
[INFO] [stdout]    --> src/coroutine.rs:141:32
[INFO] [stdout]     |
[INFO] [stdout] 141 | pub type UserDataAny = Arc<Box<Any + Send + Sync>>;
[INFO] [stdout]     |                                ^^^^^^^^^^^^^^^^^
[INFO] [stdout]     |
[INFO] [stdout]     = warning: this is accepted in the current edition (Rust 2015) but is a hard error in Rust 2021!
[INFO] [stdout]     = note: for more information, see <https://doc.rust-lang.org/nightly/edition-guide/rust-2021/warnings-promoted-to-error.html>
[INFO] [stdout] help: use `dyn`
[INFO] [stdout]     |
[INFO] [stdout] 141 | pub type UserDataAny = Arc<Box<dyn Any + Send + Sync>>;
[INFO] [stdout]     |                                +++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: trait objects without an explicit `dyn` are deprecated
[INFO] [stdout]    --> src/thread.rs:215:20
[INFO] [stdout]     |
[INFO] [stdout] 215 |     scheduler: Box<SchedulerThread + 'static>,
[INFO] [stdout]     |                    ^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout]     |
[INFO] [stdout]     = warning: this is accepted in the current edition (Rust 2015) but is a hard error in Rust 2021!
[INFO] [stdout]     = note: for more information, see <https://doc.rust-lang.org/nightly/edition-guide/rust-2021/warnings-promoted-to-error.html>
[INFO] [stdout] help: use `dyn`
[INFO] [stdout]     |
[INFO] [stdout] 215 |     scheduler: Box<dyn SchedulerThread + 'static>,
[INFO] [stdout]     |                    +++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: trait objects without an explicit `dyn` are deprecated
[INFO] [stdout]    --> src/thread.rs:294:24
[INFO] [stdout]     |
[INFO] [stdout] 294 |     PropagatePanic(Box<Any + Send + 'static>),
[INFO] [stdout]     |                        ^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout]     |
[INFO] [stdout]     = warning: this is accepted in the current edition (Rust 2015) but is a hard error in Rust 2021!
[INFO] [stdout]     = note: for more information, see <https://doc.rust-lang.org/nightly/edition-guide/rust-2021/warnings-promoted-to-error.html>
[INFO] [stdout] help: use `dyn`
[INFO] [stdout]     |
[INFO] [stdout] 294 |     PropagatePanic(Box<dyn Any + Send + 'static>),
[INFO] [stdout]     |                        +++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: trait objects without an explicit `dyn` are deprecated
[INFO] [stdout]   --> src/thunk.rs:12:17
[INFO] [stdout]    |
[INFO] [stdout] 12 |     invoke: Box<Invoke<A, R> + Send + 'a>,
[INFO] [stdout]    |                 ^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = warning: this is accepted in the current edition (Rust 2015) but is a hard error in Rust 2021!
[INFO] [stdout]    = note: for more information, see <https://doc.rust-lang.org/nightly/edition-guide/rust-2021/warnings-promoted-to-error.html>
[INFO] [stdout] help: use `dyn`
[INFO] [stdout]    |
[INFO] [stdout] 12 |     invoke: Box<dyn Invoke<A, R> + Send + 'a>,
[INFO] [stdout]    |                 +++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: trait objects without an explicit `dyn` are deprecated
[INFO] [stdout]    --> src/mod.rs:696:24
[INFO] [stdout]     |
[INFO] [stdout] 696 |     scheduler: Arc<Box<Scheduler>>,
[INFO] [stdout]     |                        ^^^^^^^^^
[INFO] [stdout]     |
[INFO] [stdout]     = warning: this is accepted in the current edition (Rust 2015) but is a hard error in Rust 2021!
[INFO] [stdout]     = note: for more information, see <https://doc.rust-lang.org/nightly/edition-guide/rust-2021/warnings-promoted-to-error.html>
[INFO] [stdout] help: use `dyn`
[INFO] [stdout]     |
[INFO] [stdout] 696 |     scheduler: Arc<Box<dyn Scheduler>>,
[INFO] [stdout]     |                        +++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: trait objects without an explicit `dyn` are deprecated
[INFO] [stdout]    --> src/mod.rs:262:35
[INFO] [stdout]     |
[INFO] [stdout] 262 |     fn spawn_thread(&self) -> Box<SchedulerThread + 'static>;
[INFO] [stdout]     |                                   ^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout]     |
[INFO] [stdout]     = warning: this is accepted in the current edition (Rust 2015) but is a hard error in Rust 2021!
[INFO] [stdout]     = note: for more information, see <https://doc.rust-lang.org/nightly/edition-guide/rust-2021/warnings-promoted-to-error.html>
[INFO] [stdout] help: use `dyn`
[INFO] [stdout]     |
[INFO] [stdout] 262 |     fn spawn_thread(&self) -> Box<dyn SchedulerThread + 'static>;
[INFO] [stdout]     |                                   +++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: trait objects without an explicit `dyn` are deprecated
[INFO] [stdout]    --> src/mod.rs:345:35
[INFO] [stdout]     |
[INFO] [stdout] 345 |     fn spawn_thread(&self) -> Box<SchedulerThread> {
[INFO] [stdout]     |                                   ^^^^^^^^^^^^^^^
[INFO] [stdout]     |
[INFO] [stdout]     = warning: this is accepted in the current edition (Rust 2015) but is a hard error in Rust 2021!
[INFO] [stdout]     = note: for more information, see <https://doc.rust-lang.org/nightly/edition-guide/rust-2021/warnings-promoted-to-error.html>
[INFO] [stdout] help: use `dyn`
[INFO] [stdout]     |
[INFO] [stdout] 345 |     fn spawn_thread(&self) -> Box<dyn SchedulerThread> {
[INFO] [stdout]     |                                   +++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: trait objects without an explicit `dyn` are deprecated
[INFO] [stdout]    --> src/mod.rs:648:41
[INFO] [stdout]     |
[INFO] [stdout] 648 |                          scheduler: Box<SchedulerThread + 'static>,
[INFO] [stdout]     |                                         ^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout]     |
[INFO] [stdout]     = warning: this is accepted in the current edition (Rust 2015) but is a hard error in Rust 2021!
[INFO] [stdout]     = note: for more information, see <https://doc.rust-lang.org/nightly/edition-guide/rust-2021/warnings-promoted-to-error.html>
[INFO] [stdout] help: use `dyn`
[INFO] [stdout]     |
[INFO] [stdout] 648 |                          scheduler: Box<dyn SchedulerThread + 'static>,
[INFO] [stdout]     |                                         +++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: trait objects without an explicit `dyn` are deprecated
[INFO] [stdout]    --> src/mod.rs:735:52
[INFO] [stdout]     |
[INFO] [stdout] 735 |     pub fn set_scheduler(&mut self, scheduler: Box<Scheduler + 'static>) -> &mut Self {
[INFO] [stdout]     |                                                    ^^^^^^^^^^^^^^^^^^^
[INFO] [stdout]     |
[INFO] [stdout]     = warning: this is accepted in the current edition (Rust 2015) but is a hard error in Rust 2021!
[INFO] [stdout]     = note: for more information, see <https://doc.rust-lang.org/nightly/edition-guide/rust-2021/warnings-promoted-to-error.html>
[INFO] [stdout] help: use `dyn`
[INFO] [stdout]     |
[INFO] [stdout] 735 |     pub fn set_scheduler(&mut self, scheduler: Box<dyn Scheduler + 'static>) -> &mut Self {
[INFO] [stdout]     |                                                    +++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: trait objects without an explicit `dyn` are deprecated
[INFO] [stdout]    --> src/evented.rs:459:35
[INFO] [stdout]     |
[INFO] [stdout] 459 |     pub fn to_trait(&self) -> Box<RcEventSourceTrait + 'static> {
[INFO] [stdout]     |                                   ^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout]     |
[INFO] [stdout]     = warning: this is accepted in the current edition (Rust 2015) but is a hard error in Rust 2021!
[INFO] [stdout]     = note: for more information, see <https://doc.rust-lang.org/nightly/edition-guide/rust-2021/warnings-promoted-to-error.html>
[INFO] [stdout] help: use `dyn`
[INFO] [stdout]     |
[INFO] [stdout] 459 |     pub fn to_trait(&self) -> Box<dyn RcEventSourceTrait + 'static> {
[INFO] [stdout]     |                                   +++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: trait objects without an explicit `dyn` are deprecated
[INFO] [stdout]    --> src/thread.rs:223:56
[INFO] [stdout]     |
[INFO] [stdout] 223 |     pub fn new(shared: RcHandlerShared, scheduler: Box<SchedulerThread>) -> Self {
[INFO] [stdout]     |                                                        ^^^^^^^^^^^^^^^
[INFO] [stdout]     |
[INFO] [stdout]     = warning: this is accepted in the current edition (Rust 2015) but is a hard error in Rust 2021!
[INFO] [stdout]     = note: for more information, see <https://doc.rust-lang.org/nightly/edition-guide/rust-2021/warnings-promoted-to-error.html>
[INFO] [stdout] help: use `dyn`
[INFO] [stdout]     |
[INFO] [stdout] 223 |     pub fn new(shared: RcHandlerShared, scheduler: Box<dyn SchedulerThread>) -> Self {
[INFO] [stdout]     |                                                        +++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: trait objects without an explicit `dyn` are deprecated
[INFO] [stdout]    --> src/mod.rs:532:40
[INFO] [stdout]     |
[INFO] [stdout] 532 |             if (&***arcref.owner() as &Any).downcast_ref::<T>().is_some() {
[INFO] [stdout]     |                                        ^^^
[INFO] [stdout]     |
[INFO] [stdout]     = warning: this is accepted in the current edition (Rust 2015) but is a hard error in Rust 2021!
[INFO] [stdout]     = note: for more information, see <https://doc.rust-lang.org/nightly/edition-guide/rust-2021/warnings-promoted-to-error.html>
[INFO] [stdout] help: use `dyn`
[INFO] [stdout]     |
[INFO] [stdout] 532 |             if (&***arcref.owner() as &dyn Any).downcast_ref::<T>().is_some() {
[INFO] [stdout]     |                                        +++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: trait objects without an explicit `dyn` are deprecated
[INFO] [stdout]    --> src/mod.rs:533:49
[INFO] [stdout]     |
[INFO] [stdout] 533 |                 Some(arcref.map(|ud| (&**ud as &Any).downcast_ref::<T>().unwrap())
[INFO] [stdout]     |                                                 ^^^
[INFO] [stdout]     |
[INFO] [stdout]     = warning: this is accepted in the current edition (Rust 2015) but is a hard error in Rust 2021!
[INFO] [stdout]     = note: for more information, see <https://doc.rust-lang.org/nightly/edition-guide/rust-2021/warnings-promoted-to-error.html>
[INFO] [stdout] help: use `dyn`
[INFO] [stdout]     |
[INFO] [stdout] 533 |                 Some(arcref.map(|ud| (&**ud as &dyn Any).downcast_ref::<T>().unwrap())
[INFO] [stdout]     |                                                 +++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: trait objects without an explicit `dyn` are deprecated
[INFO] [stdout]    --> src/mod.rs:971:36
[INFO] [stdout]     |
[INFO] [stdout] 971 |         if (&***arcref.owner() as &Any).downcast_ref::<T>().is_some() {
[INFO] [stdout]     |                                    ^^^
[INFO] [stdout]     |
[INFO] [stdout]     = warning: this is accepted in the current edition (Rust 2015) but is a hard error in Rust 2021!
[INFO] [stdout]     = note: for more information, see <https://doc.rust-lang.org/nightly/edition-guide/rust-2021/warnings-promoted-to-error.html>
[INFO] [stdout] help: use `dyn`
[INFO] [stdout]     |
[INFO] [stdout] 971 |         if (&***arcref.owner() as &dyn Any).downcast_ref::<T>().is_some() {
[INFO] [stdout]     |                                    +++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: trait objects without an explicit `dyn` are deprecated
[INFO] [stdout]    --> src/mod.rs:972:45
[INFO] [stdout]     |
[INFO] [stdout] 972 |             Some(arcref.map(|ud| (&**ud as &Any).downcast_ref::<T>().unwrap())
[INFO] [stdout]     |                                             ^^^
[INFO] [stdout]     |
[INFO] [stdout]     = warning: this is accepted in the current edition (Rust 2015) but is a hard error in Rust 2021!
[INFO] [stdout]     = note: for more information, see <https://doc.rust-lang.org/nightly/edition-guide/rust-2021/warnings-promoted-to-error.html>
[INFO] [stdout] help: use `dyn`
[INFO] [stdout]     |
[INFO] [stdout] 972 |             Some(arcref.map(|ud| (&**ud as &dyn Any).downcast_ref::<T>().unwrap())
[INFO] [stdout]     |                                             +++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: variable does not need to be mutable
[INFO] [stdout]    --> src/coroutine.rs:376:17
[INFO] [stdout]     |
[INFO] [stdout] 376 |             let mut common = &mut event_source.common_mut();
[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] error[E0446]: private type `ReceiverCore<T>` in public interface
[INFO] [stdout]   --> src/sync/mpsc.rs:35:5
[INFO] [stdout]    |
[INFO] [stdout] 26 | struct ReceiverCore<T> {
[INFO] [stdout]    | ---------------------- `ReceiverCore<T>` declared as private
[INFO] [stdout] ...
[INFO] [stdout] 35 |     type Raw = ReceiverCore<T>;
[INFO] [stdout]    |     ^^^^^^^^ can't leak private type
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error[E0446]: private type `TimerCore` in public interface
[INFO] [stdout]   --> src/timer.rs:47:5
[INFO] [stdout]    |
[INFO] [stdout] 18 | struct TimerCore {
[INFO] [stdout]    | ---------------- `TimerCore` declared as private
[INFO] [stdout] ...
[INFO] [stdout] 47 |     type Raw = TimerCore;
[INFO] [stdout]    |     ^^^^^^^^ can't leak private type
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error: aborting due to 2 previous errors; 21 warnings emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] For more information about this error, try `rustc --explain E0446`.
[INFO] [stdout] 
[INFO] [stderr] error: could not compile `mioco` due to 3 previous errors; 21 warnings emitted
[INFO] running `Command { std: "docker" "inspect" "41ffd928b6b582a837b6cb9bfcb5380500a8f6cddd257ae443a034e6ff486b48", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "41ffd928b6b582a837b6cb9bfcb5380500a8f6cddd257ae443a034e6ff486b48", kill_on_drop: false }`
[INFO] [stdout] 41ffd928b6b582a837b6cb9bfcb5380500a8f6cddd257ae443a034e6ff486b48
