[INFO] fetching crate hawk-ws 0.1.1...
[INFO] testing hawk-ws-0.1.1 against 1.54.0 for beta-1.55-1
[INFO] extracting crate hawk-ws 0.1.1 into /workspace/builds/worker-87/source
[INFO] validating manifest of crates.io crate hawk-ws 0.1.1 on toolchain 1.54.0
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+1.54.0" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }`
[INFO] started tweaking crates.io crate hawk-ws 0.1.1
[INFO] finished tweaking crates.io crate hawk-ws 0.1.1
[INFO] tweaked toml for crates.io crate hawk-ws 0.1.1 written to /workspace/builds/worker-87/source/Cargo.toml
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+1.54.0" "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" "+1.54.0" "fetch" "--manifest-path" "Cargo.toml", 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]  Downloading crates ...
[INFO] [stderr]   Downloaded sha1 v0.2.0
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-87/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-87/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" "+1.54.0" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] 7cdec757bbd93e35be0016b2fc428eb11e65c5f4a12c7e8f720bed79352a8ae4
[INFO] running `Command { std: "docker" "start" "-a" "7cdec757bbd93e35be0016b2fc428eb11e65c5f4a12c7e8f720bed79352a8ae4", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "7cdec757bbd93e35be0016b2fc428eb11e65c5f4a12c7e8f720bed79352a8ae4", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "7cdec757bbd93e35be0016b2fc428eb11e65c5f4a12c7e8f720bed79352a8ae4", kill_on_drop: false }`
[INFO] [stdout] 7cdec757bbd93e35be0016b2fc428eb11e65c5f4a12c7e8f720bed79352a8ae4
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-87/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-87/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" "+1.54.0" "build" "--frozen" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] 37c0164d2a702266182cc74d14b3f13ec67e15c80c17640af4c7073ef4e4504c
[INFO] running `Command { std: "docker" "start" "-a" "37c0164d2a702266182cc74d14b3f13ec67e15c80c17640af4c7073ef4e4504c", kill_on_drop: false }`
[INFO] [stderr]     Blocking waiting for file lock on package cache
[INFO] [stderr]    Compiling sha1 v0.2.0
[INFO] [stderr]    Compiling slab v0.3.0
[INFO] [stderr]    Compiling iovec v0.1.4
[INFO] [stderr]    Compiling net2 v0.2.37
[INFO] [stderr]    Compiling rand v0.4.6
[INFO] [stderr]    Compiling bytes v0.4.12
[INFO] [stderr]    Compiling mio v0.6.23
[INFO] [stderr]    Compiling rand v0.3.23
[INFO] [stderr]    Compiling hawk-ws v0.1.1 (/opt/rustwide/workdir)
[INFO] [stdout] warning: trait objects without an explicit `dyn` are deprecated
[INFO] [stdout]   --> src/result.rs:64:16
[INFO] [stdout]    |
[INFO] [stdout] 64 |     Custom(Box<StdError + Send + Sync>),
[INFO] [stdout]    |                ^^^^^^^^^^^^^^^^^^^^^^ help: use `dyn`: `dyn StdError + Send + Sync`
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(bare_trait_objects)]` on by default
[INFO] [stdout]    = warning: this was previously accepted by the compiler but is being phased out; it will become a hard error in the 2021 edition!
[INFO] [stdout]    = note: for more information, see issue #80165 <https://github.com/rust-lang/rust/issues/80165>
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: trait objects without an explicit `dyn` are deprecated
[INFO] [stdout]   --> src/result.rs:84:34
[INFO] [stdout]    |
[INFO] [stdout] 84 |     pub fn into_box(self) -> Box<StdError> {
[INFO] [stdout]    |                                  ^^^^^^^^ help: use `dyn`: `dyn StdError`
[INFO] [stdout]    |
[INFO] [stdout]    = warning: this was previously accepted by the compiler but is being phased out; it will become a hard error in the 2021 edition!
[INFO] [stdout]    = note: for more information, see issue #80165 <https://github.com/rust-lang/rust/issues/80165>
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: trait objects without an explicit `dyn` are deprecated
[INFO] [stdout]    --> src/result.rs:131:32
[INFO] [stdout]     |
[INFO] [stdout] 131 |     fn cause(&self) -> Option<&StdError> {
[INFO] [stdout]     |                                ^^^^^^^^ help: use `dyn`: `dyn StdError`
[INFO] [stdout]     |
[INFO] [stdout]     = warning: this was previously accepted by the compiler but is being phased out; it will become a hard error in the 2021 edition!
[INFO] [stdout]     = note: for more information, see issue #80165 <https://github.com/rust-lang/rust/issues/80165>
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 3 warnings emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]     Finished dev [unoptimized + debuginfo] target(s) in 4.88s
[INFO] running `Command { std: "docker" "inspect" "37c0164d2a702266182cc74d14b3f13ec67e15c80c17640af4c7073ef4e4504c", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "37c0164d2a702266182cc74d14b3f13ec67e15c80c17640af4c7073ef4e4504c", kill_on_drop: false }`
[INFO] [stdout] 37c0164d2a702266182cc74d14b3f13ec67e15c80c17640af4c7073ef4e4504c
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-87/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-87/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" "+1.54.0" "test" "--frozen" "--no-run" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] 8143af1fe08e8da05af8bce39e987bff4c2101b454a628ed2e8bcbb5289f12e3
[INFO] running `Command { std: "docker" "start" "-a" "8143af1fe08e8da05af8bce39e987bff4c2101b454a628ed2e8bcbb5289f12e3", kill_on_drop: false }`
[INFO] [stderr]    Compiling ucd-util v0.1.8
[INFO] [stderr]    Compiling regex v0.2.11
[INFO] [stderr]    Compiling utf8-ranges v1.0.4
[INFO] [stderr]    Compiling term v0.4.6
[INFO] [stderr]    Compiling thread_local v0.3.6
[INFO] [stderr]    Compiling atty v0.2.14
[INFO] [stderr]    Compiling aho-corasick v0.6.10
[INFO] [stdout] warning: trait objects without an explicit `dyn` are deprecated
[INFO] [stdout]   --> src/result.rs:64:16
[INFO] [stdout]    |
[INFO] [stdout] 64 |     Custom(Box<StdError + Send + Sync>),
[INFO] [stdout]    |                ^^^^^^^^^^^^^^^^^^^^^^ help: use `dyn`: `dyn StdError + Send + Sync`
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(bare_trait_objects)]` on by default
[INFO] [stdout]    = warning: this was previously accepted by the compiler but is being phased out; it will become a hard error in the 2021 edition!
[INFO] [stdout]    = note: for more information, see issue #80165 <https://github.com/rust-lang/rust/issues/80165>
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: trait objects without an explicit `dyn` are deprecated
[INFO] [stdout]   --> src/result.rs:84:34
[INFO] [stdout]    |
[INFO] [stdout] 84 |     pub fn into_box(self) -> Box<StdError> {
[INFO] [stdout]    |                                  ^^^^^^^^ help: use `dyn`: `dyn StdError`
[INFO] [stdout]    |
[INFO] [stdout]    = warning: this was previously accepted by the compiler but is being phased out; it will become a hard error in the 2021 edition!
[INFO] [stdout]    = note: for more information, see issue #80165 <https://github.com/rust-lang/rust/issues/80165>
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: trait objects without an explicit `dyn` are deprecated
[INFO] [stdout]    --> src/result.rs:131:32
[INFO] [stdout]     |
[INFO] [stdout] 131 |     fn cause(&self) -> Option<&StdError> {
[INFO] [stdout]     |                                ^^^^^^^^ help: use `dyn`: `dyn StdError`
[INFO] [stdout]     |
[INFO] [stdout]     = warning: this was previously accepted by the compiler but is being phased out; it will become a hard error in the 2021 edition!
[INFO] [stdout]     = note: for more information, see issue #80165 <https://github.com/rust-lang/rust/issues/80165>
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 3 warnings emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]    Compiling clap v2.33.3
[INFO] [stderr]    Compiling regex-syntax v0.5.6
[INFO] [stderr]    Compiling env_logger v0.4.3
[INFO] [stderr]    Compiling hawk-ws v0.1.1 (/opt/rustwide/workdir)
[INFO] [stdout] error[E0463]: can't find crate for `ws`
[INFO] [stdout]  --> examples/autobahn-server.rs:4:1
[INFO] [stdout]   |
[INFO] [stdout] 4 | extern crate ws;
[INFO] [stdout]   | ^^^^^^^^^^^^^^^^ can't find crate
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error: aborting due to previous error
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] For more information about this error, try `rustc --explain E0463`.
[INFO] [stdout] 
[INFO] [stdout] error[E0463]: can't find crate for `ws`
[INFO] [stdout]  --> examples/remote_addr.rs:2:1
[INFO] [stdout]   |
[INFO] [stdout] 2 | extern crate ws;
[INFO] [stdout]   | ^^^^^^^^^^^^^^^^ can't find crate
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error: aborting due to previous error
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] For more information about this error, try `rustc --explain E0463`.
[INFO] [stdout] 
[INFO] [stderr] error: could not compile `hawk-ws`
[INFO] [stderr] 
[INFO] [stderr] To learn more, run the command again with --verbose.
[INFO] [stderr] warning: build failed, waiting for other jobs to finish...
[INFO] [stdout] error[E0463]: can't find crate for `ws`
[INFO] [stdout]  --> examples/unsafe-ssl-client.rs:5:1
[INFO] [stdout]   |
[INFO] [stdout] 5 | extern crate ws;
[INFO] [stdout]   | ^^^^^^^^^^^^^^^^ can't find crate
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error: aborting due to previous error
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] For more information about this error, try `rustc --explain E0463`.
[INFO] [stdout] 
[INFO] [stdout] error[E0463]: can't find crate for `ws`
[INFO] [stdout]  --> examples/shared.rs:5:1
[INFO] [stdout]   |
[INFO] [stdout] 5 | extern crate ws;
[INFO] [stdout]   | ^^^^^^^^^^^^^^^^ can't find crate
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error: aborting due to previous error
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] For more information about this error, try `rustc --explain E0463`.
[INFO] [stdout] 
[INFO] [stdout] error[E0463]: can't find crate for `ws`
[INFO] [stdout]  --> examples/bench-server.rs:2:1
[INFO] [stdout]   |
[INFO] [stdout] 2 | extern crate ws;
[INFO] [stdout]   | ^^^^^^^^^^^^^^^^ can't find crate
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error: aborting due to previous error
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] For more information about this error, try `rustc --explain E0463`.
[INFO] [stdout] 
[INFO] [stdout] error[E0463]: can't find crate for `ws`
[INFO] [stdout]  --> examples/external_shutdown.rs:1:1
[INFO] [stdout]   |
[INFO] [stdout] 1 | extern crate ws;
[INFO] [stdout]   | ^^^^^^^^^^^^^^^^ can't find crate
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error[E0463]: can't find crate for `ws`
[INFO] [stdout]  --> examples/threaded.rs:4:1
[INFO] [stdout]   |
[INFO] [stdout] 4 | extern crate ws;
[INFO] [stdout]   | ^^^^^^^^^^^^^^^^ can't find crate
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error[E0463]: can't find crate for `ws`
[INFO] [stdout]  --> examples/autobahn-client.rs:2:1
[INFO] [stdout]   |
[INFO] [stdout] 2 | extern crate ws;
[INFO] [stdout]   | ^^^^^^^^^^^^^^^^ can't find crate
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error[E0463]: can't find crate for `ws`
[INFO] [stdout]   --> examples/peer2peer.rs:29:1
[INFO] [stdout]    |
[INFO] [stdout] 29 | extern crate ws;
[INFO] [stdout]    | ^^^^^^^^^^^^^^^^ can't find crate
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error[E0463]: can't find crate for `ws`
[INFO] [stdout]  --> examples/bench.rs:7:1
[INFO] [stdout]   |
[INFO] [stdout] 7 | extern crate ws;
[INFO] [stdout]   | ^^^^^^^^^^^^^^^^ can't find crate
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error[E0463]: can't find crate for `ws`
[INFO] [stdout]  --> examples/server.rs:4:1
[INFO] [stdout]   |
[INFO] [stdout] 4 | extern crate ws;
[INFO] [stdout]   | ^^^^^^^^^^^^^^^^ can't find crate
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error: aborting due to previous error
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] For more information about this error, try `rustc --explain E0463`.
[INFO] [stdout] 
[INFO] [stdout] error: aborting due to previous error
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] For more information about this error, try `rustc --explain E0463`.
[INFO] [stdout] 
[INFO] [stdout] error: aborting due to previous error
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] For more information about this error, try `rustc --explain E0463`.
[INFO] [stdout] 
[INFO] [stdout] error: aborting due to previous error
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] For more information about this error, try `rustc --explain E0463`.
[INFO] [stdout] 
[INFO] [stdout] error: aborting due to previous error
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error: aborting due to previous error
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] For more information about this error, try `rustc --explain E0463`.
[INFO] [stdout] 
[INFO] [stdout] For more information about this error, try `rustc --explain E0463`.
[INFO] [stdout] 
[INFO] [stdout] error[E0463]: can't find crate for `ws`
[INFO] [stdout]  --> examples/client.rs:4:1
[INFO] [stdout]   |
[INFO] [stdout] 4 | extern crate ws;
[INFO] [stdout]   | ^^^^^^^^^^^^^^^^ can't find crate
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error[E0463]: can't find crate for `ws`
[INFO] [stdout]  --> tests/shutdown.rs:1:1
[INFO] [stdout]   |
[INFO] [stdout] 1 | extern crate ws;
[INFO] [stdout]   | ^^^^^^^^^^^^^^^^ can't find crate
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error: aborting due to previous error
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] For more information about this error, try `rustc --explain E0463`.
[INFO] [stdout] 
[INFO] [stdout] error[E0463]: can't find crate for `ws`
[INFO] [stdout]  --> examples/pong.rs:4:1
[INFO] [stdout]   |
[INFO] [stdout] 4 | extern crate ws;
[INFO] [stdout]   | ^^^^^^^^^^^^^^^^ can't find crate
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error[E0463]: can't find crate for `ws`
[INFO] [stdout]  --> examples/router.rs:4:1
[INFO] [stdout]   |
[INFO] [stdout] 4 | extern crate ws;
[INFO] [stdout]   | ^^^^^^^^^^^^^^^^ can't find crate
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error[E0463]: can't find crate for `ws`
[INFO] [stdout]  --> examples/cli.rs:7:1
[INFO] [stdout]   |
[INFO] [stdout] 7 | extern crate ws;
[INFO] [stdout]   | ^^^^^^^^^^^^^^^^ can't find crate
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error: aborting due to previous error
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] For more information about this error, try `rustc --explain E0463`.
[INFO] [stdout] 
[INFO] [stdout] error: aborting due to previous error
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] For more information about this error, try `rustc --explain E0463`.
[INFO] [stdout] 
[INFO] [stdout] error[E0463]: can't find crate for `ws`
[INFO] [stdout]  --> tests/bind.rs:1:1
[INFO] [stdout]   |
[INFO] [stdout] 1 | extern crate ws;
[INFO] [stdout]   | ^^^^^^^^^^^^^^^^ can't find crate
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error: aborting due to previous error
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] For more information about this error, try `rustc --explain E0463`.
[INFO] [stdout] 
[INFO] [stdout] error: aborting due to previous error
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] For more information about this error, try `rustc --explain E0463`.
[INFO] [stdout] 
[INFO] [stdout] error: aborting due to previous error
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] For more information about this error, try `rustc --explain E0463`.
[INFO] [stdout] 
[INFO] [stdout] error[E0463]: can't find crate for `ws`
[INFO] [stdout]   --> examples/channel.rs:11:1
[INFO] [stdout]    |
[INFO] [stdout] 11 | extern crate ws;
[INFO] [stdout]    | ^^^^^^^^^^^^^^^^ can't find crate
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error: aborting due to previous error
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] For more information about this error, try `rustc --explain E0463`.
[INFO] [stdout] 
[INFO] [stdout] error[E0463]: can't find crate for `ws`
[INFO] [stdout]   --> examples/ssl-server.rs:13:1
[INFO] [stdout]    |
[INFO] [stdout] 13 | extern crate ws;
[INFO] [stdout]    | ^^^^^^^^^^^^^^^^ can't find crate
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error: aborting due to previous error
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] For more information about this error, try `rustc --explain E0463`.
[INFO] [stdout] 
[INFO] [stdout] warning: trait objects without an explicit `dyn` are deprecated
[INFO] [stdout]   --> src/result.rs:64:16
[INFO] [stdout]    |
[INFO] [stdout] 64 |     Custom(Box<StdError + Send + Sync>),
[INFO] [stdout]    |                ^^^^^^^^^^^^^^^^^^^^^^ help: use `dyn`: `dyn StdError + Send + Sync`
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(bare_trait_objects)]` on by default
[INFO] [stdout]    = warning: this was previously accepted by the compiler but is being phased out; it will become a hard error in the 2021 edition!
[INFO] [stdout]    = note: for more information, see issue #80165 <https://github.com/rust-lang/rust/issues/80165>
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: trait objects without an explicit `dyn` are deprecated
[INFO] [stdout]   --> src/result.rs:84:34
[INFO] [stdout]    |
[INFO] [stdout] 84 |     pub fn into_box(self) -> Box<StdError> {
[INFO] [stdout]    |                                  ^^^^^^^^ help: use `dyn`: `dyn StdError`
[INFO] [stdout]    |
[INFO] [stdout]    = warning: this was previously accepted by the compiler but is being phased out; it will become a hard error in the 2021 edition!
[INFO] [stdout]    = note: for more information, see issue #80165 <https://github.com/rust-lang/rust/issues/80165>
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: trait objects without an explicit `dyn` are deprecated
[INFO] [stdout]    --> src/result.rs:131:32
[INFO] [stdout]     |
[INFO] [stdout] 131 |     fn cause(&self) -> Option<&StdError> {
[INFO] [stdout]     |                                ^^^^^^^^ help: use `dyn`: `dyn StdError`
[INFO] [stdout]     |
[INFO] [stdout]     = warning: this was previously accepted by the compiler but is being phased out; it will become a hard error in the 2021 edition!
[INFO] [stdout]     = note: for more information, see issue #80165 <https://github.com/rust-lang/rust/issues/80165>
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused closure that must be used
[INFO] [stdout]   --> src/factory.rs:89:9
[INFO] [stdout]    |
[INFO] [stdout] 89 |         factory.connection_made(Sender::new(mio::Token(0), chn, 0));
[INFO] [stdout]    |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(unused_must_use)]` on by default
[INFO] [stdout]    = note: closures are lazy and do nothing unless called
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 4 warnings emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr] error: build failed
[INFO] running `Command { std: "docker" "inspect" "8143af1fe08e8da05af8bce39e987bff4c2101b454a628ed2e8bcbb5289f12e3", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "8143af1fe08e8da05af8bce39e987bff4c2101b454a628ed2e8bcbb5289f12e3", kill_on_drop: false }`
[INFO] [stdout] 8143af1fe08e8da05af8bce39e987bff4c2101b454a628ed2e8bcbb5289f12e3
