[INFO] fetching crate engine_io_server 0.1.0...
[INFO] checking engine_io_server-0.1.0 against 1.55.0 for beta-1.56-3
[INFO] extracting crate engine_io_server 0.1.0 into /workspace/builds/worker-57/source
[INFO] validating manifest of crates.io crate engine_io_server 0.1.0 on toolchain 1.55.0
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+1.55.0" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }`
[INFO] started tweaking crates.io crate engine_io_server 0.1.0
[INFO] finished tweaking crates.io crate engine_io_server 0.1.0
[INFO] tweaked toml for crates.io crate engine_io_server 0.1.0 written to /workspace/builds/worker-57/source/Cargo.toml
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+1.55.0" "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" "+1.55.0" "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] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-57/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-57/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:a89201d6b5b9fd45c15d5952ece0a0129e7e80cb26ec023fd59cf09bc26f1604" "/opt/rustwide/cargo-home/bin/cargo" "+1.55.0" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] 8c5fc22c70121afc5d3f85f8a3d80aebc6e6a1bcf0d6462ed302bbf6a97b8aac
[INFO] running `Command { std: "docker" "start" "-a" "8c5fc22c70121afc5d3f85f8a3d80aebc6e6a1bcf0d6462ed302bbf6a97b8aac", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "8c5fc22c70121afc5d3f85f8a3d80aebc6e6a1bcf0d6462ed302bbf6a97b8aac", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "8c5fc22c70121afc5d3f85f8a3d80aebc6e6a1bcf0d6462ed302bbf6a97b8aac", kill_on_drop: false }`
[INFO] [stdout] 8c5fc22c70121afc5d3f85f8a3d80aebc6e6a1bcf0d6462ed302bbf6a97b8aac
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-57/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-57/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:a89201d6b5b9fd45c15d5952ece0a0129e7e80cb26ec023fd59cf09bc26f1604" "/opt/rustwide/cargo-home/bin/cargo" "+1.55.0" "check" "--frozen" "--all" "--all-targets" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] f26e003e825ebef959f72d4d661c213b7ecefdc645e7b160cf06413d79c3bf3b
[INFO] running `Command { std: "docker" "start" "-a" "f26e003e825ebef959f72d4d661c213b7ecefdc645e7b160cf06413d79c3bf3b", kill_on_drop: false }`
[INFO] [stderr]    Compiling syn v1.0.80
[INFO] [stderr]    Compiling futures-core v0.3.17
[INFO] [stderr]     Checking futures-sink v0.3.17
[INFO] [stderr]    Compiling libc v0.2.103
[INFO] [stderr]    Compiling unicode-segmentation v1.8.0
[INFO] [stderr]     Checking strum v0.18.0
[INFO] [stderr]    Compiling futures-util v0.3.17
[INFO] [stderr]     Checking tokio v0.2.25
[INFO] [stderr]     Checking engine_io_parser v0.2.0
[INFO] [stderr]    Compiling heck v0.3.3
[INFO] [stderr]     Checking futures-channel v0.3.17
[INFO] [stderr]     Checking getrandom v0.2.3
[INFO] [stderr]     Checking uuid v0.8.2
[INFO] [stderr]    Compiling futures-macro v0.3.17
[INFO] [stderr]    Compiling serde_derive v1.0.130
[INFO] [stderr]    Compiling async-trait v0.1.51
[INFO] [stderr]    Compiling strum_macros v0.18.0
[INFO] [stderr]     Checking serde v1.0.130
[INFO] [stderr]     Checking futures-executor v0.3.17
[INFO] [stderr]     Checking futures v0.3.17
[INFO] [stderr]     Checking serde_json v1.0.68
[INFO] [stderr]     Checking engine_io_server v0.1.0 (/opt/rustwide/workdir)
[INFO] [stdout] warning: unused variable: `reason`
[INFO] [stdout]    --> src/socket.rs:363:34
[INFO] [stdout]     |
[INFO] [stdout] 363 |     async fn on_close(&mut self, reason: SocketError, description: &str) {
[INFO] [stdout]     |                                  ^^^^^^ help: if this is intentional, prefix it with an underscore: `_reason`
[INFO] [stdout]     |
[INFO] [stdout]     = note: `#[warn(unused_variables)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `description`
[INFO] [stdout]    --> src/socket.rs:363:55
[INFO] [stdout]     |
[INFO] [stdout] 363 |     async fn on_close(&mut self, reason: SocketError, description: &str) {
[INFO] [stdout]     |                                                       ^^^^^^^^^^^ help: if this is intentional, prefix it with an underscore: `_description`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: variable does not need to be mutable
[INFO] [stdout]   --> src/socket.rs:55:13
[INFO] [stdout]    |
[INFO] [stdout] 55 |         let mut holder = TransportHolder {
[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: unused variable: `reason`
[INFO] [stdout]    --> src/socket.rs:363:34
[INFO] [stdout]     |
[INFO] [stdout] 363 |     async fn on_close(&mut self, reason: SocketError, description: &str) {
[INFO] [stdout]     |                                  ^^^^^^ help: if this is intentional, prefix it with an underscore: `_reason`
[INFO] [stdout]     |
[INFO] [stdout]     = note: `#[warn(unused_variables)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `description`
[INFO] [stdout]    --> src/socket.rs:363:55
[INFO] [stdout]     |
[INFO] [stdout] 363 |     async fn on_close(&mut self, reason: SocketError, description: &str) {
[INFO] [stdout]     |                                                       ^^^^^^^^^^^ help: if this is intentional, prefix it with an underscore: `_description`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: field is never read: `remote_address`
[INFO] [stdout]   --> src/socket.rs:33:5
[INFO] [stdout]    |
[INFO] [stdout] 33 |     remote_address: String,
[INFO] [stdout]    |     ^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(dead_code)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: field is never read: `transport_event_sender`
[INFO] [stdout]   --> src/socket.rs:45:5
[INFO] [stdout]    |
[INFO] [stdout] 45 |     transport_event_sender: mpsc::Sender<TransportEvent>,
[INFO] [stdout]    |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: variable does not need to be mutable
[INFO] [stdout]   --> src/socket.rs:55:13
[INFO] [stdout]    |
[INFO] [stdout] 55 |         let mut holder = TransportHolder {
[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: unused `Result` that must be used
[INFO] [stdout]    --> src/socket.rs:172:9
[INFO] [stdout]     |
[INFO] [stdout] 172 | /         self.event_sender
[INFO] [stdout] 173 | |             .send(SocketEvent::Open {
[INFO] [stdout] 174 | |                 socket_id: self.id.clone(),
[INFO] [stdout] 175 | |             })
[INFO] [stdout] 176 | |             .await;
[INFO] [stdout]     | |___________________^
[INFO] [stdout]     |
[INFO] [stdout]     = note: `#[warn(unused_must_use)]` on by default
[INFO] [stdout]     = note: this `Result` may be an `Err` variant, which should be handled
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused return value of `TransportImpl::close` that must be used
[INFO] [stdout]    --> src/socket.rs:187:17
[INFO] [stdout]     |
[INFO] [stdout] 187 |                 self.transport_holder.transport.close();
[INFO] [stdout]     |                 ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused `Result` that must be used
[INFO] [stdout]    --> src/socket.rs:284:13
[INFO] [stdout]     |
[INFO] [stdout] 284 | /             self.event_sender
[INFO] [stdout] 285 | |                 .send(SocketEvent::Flush {
[INFO] [stdout] 286 | |                     socket_id: id.clone(),
[INFO] [stdout] 287 | |                 })
[INFO] [stdout] 288 | |                 .await;
[INFO] [stdout]     | |_______________________^
[INFO] [stdout]     |
[INFO] [stdout]     = note: this `Result` may be an `Err` variant, which should be handled
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: field is never read: `remote_address`
[INFO] [stdout]   --> src/socket.rs:33:5
[INFO] [stdout]    |
[INFO] [stdout] 33 |     remote_address: String,
[INFO] [stdout]    |     ^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(dead_code)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: field is never read: `transport_event_sender`
[INFO] [stdout]   --> src/socket.rs:45:5
[INFO] [stdout]    |
[INFO] [stdout] 45 |     transport_event_sender: mpsc::Sender<TransportEvent>,
[INFO] [stdout]    |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 8 warnings emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused `Result` that must be used
[INFO] [stdout]    --> src/socket.rs:172:9
[INFO] [stdout]     |
[INFO] [stdout] 172 | /         self.event_sender
[INFO] [stdout] 173 | |             .send(SocketEvent::Open {
[INFO] [stdout] 174 | |                 socket_id: self.id.clone(),
[INFO] [stdout] 175 | |             })
[INFO] [stdout] 176 | |             .await;
[INFO] [stdout]     | |___________________^
[INFO] [stdout]     |
[INFO] [stdout]     = note: `#[warn(unused_must_use)]` on by default
[INFO] [stdout]     = note: this `Result` may be an `Err` variant, which should be handled
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused return value of `TransportImpl::close` that must be used
[INFO] [stdout]    --> src/socket.rs:187:17
[INFO] [stdout]     |
[INFO] [stdout] 187 |                 self.transport_holder.transport.close();
[INFO] [stdout]     |                 ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused `Result` that must be used
[INFO] [stdout]    --> src/socket.rs:284:13
[INFO] [stdout]     |
[INFO] [stdout] 284 | /             self.event_sender
[INFO] [stdout] 285 | |                 .send(SocketEvent::Flush {
[INFO] [stdout] 286 | |                     socket_id: id.clone(),
[INFO] [stdout] 287 | |                 })
[INFO] [stdout] 288 | |                 .await;
[INFO] [stdout]     | |_______________________^
[INFO] [stdout]     |
[INFO] [stdout]     = note: this `Result` may be an `Err` variant, which should be handled
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 8 warnings emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]     Finished dev [unoptimized + debuginfo] target(s) in 35.08s
[INFO] running `Command { std: "docker" "inspect" "f26e003e825ebef959f72d4d661c213b7ecefdc645e7b160cf06413d79c3bf3b", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "f26e003e825ebef959f72d4d661c213b7ecefdc645e7b160cf06413d79c3bf3b", kill_on_drop: false }`
[INFO] [stdout] f26e003e825ebef959f72d4d661c213b7ecefdc645e7b160cf06413d79c3bf3b
