[INFO] fetching crate mai 0.1.0...
[INFO] checking mai-0.1.0 against 1.55.0 for beta-1.56-3
[INFO] extracting crate mai 0.1.0 into /workspace/builds/worker-79/source
[INFO] validating manifest of crates.io crate mai 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 mai 0.1.0
[INFO] finished tweaking crates.io crate mai 0.1.0
[INFO] tweaked toml for crates.io crate mai 0.1.0 written to /workspace/builds/worker-79/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]  Downloading crates ...
[INFO] [stderr]   Downloaded lifeguard v0.5.2
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-79/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-79/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] cc9e765536092fb3269e76da2b7ff96930177d798c35578a4f568ebb26fb0554
[INFO] running `Command { std: "docker" "start" "-a" "cc9e765536092fb3269e76da2b7ff96930177d798c35578a4f568ebb26fb0554", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "cc9e765536092fb3269e76da2b7ff96930177d798c35578a4f568ebb26fb0554", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "cc9e765536092fb3269e76da2b7ff96930177d798c35578a4f568ebb26fb0554", kill_on_drop: false }`
[INFO] [stdout] cc9e765536092fb3269e76da2b7ff96930177d798c35578a4f568ebb26fb0554
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-79/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-79/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] 399cf46cf75e6b4d126a1bcdbac617cc9f4ac39cc3ef152f65e18b686bdc0cc4
[INFO] running `Command { std: "docker" "start" "-a" "399cf46cf75e6b4d126a1bcdbac617cc9f4ac39cc3ef152f65e18b686bdc0cc4", kill_on_drop: false }`
[INFO] [stderr]    Compiling winapi-build v0.1.1
[INFO] [stderr]    Compiling libc v0.2.103
[INFO] [stderr]    Compiling log v0.4.14
[INFO] [stderr]     Checking winapi v0.2.8
[INFO] [stderr]     Checking cfg-if v1.0.0
[INFO] [stderr]     Checking cfg-if v0.1.10
[INFO] [stderr]     Checking bitflags v0.4.0
[INFO] [stderr]     Checking slab v0.1.3
[INFO] [stderr]     Checking bytes v0.3.0
[INFO] [stderr]     Checking lifeguard v0.5.2
[INFO] [stderr]    Compiling ws2_32-sys v0.2.1
[INFO] [stderr]    Compiling kernel32-sys v0.2.2
[INFO] [stderr]     Checking log v0.3.9
[INFO] [stderr]     Checking net2 v0.2.37
[INFO] [stderr]     Checking nix v0.5.1
[INFO] [stderr]     Checking time v0.1.44
[INFO] [stderr]     Checking miow v0.1.5
[INFO] [stderr]     Checking mio v0.5.1
[INFO] [stderr]     Checking mai v0.1.0 (/opt/rustwide/workdir)
[INFO] [stdout] warning: use of deprecated macro `try`: use the `?` operator instead
[INFO] [stdout]    --> src/evented_frame_stream.rs:211:7
[INFO] [stdout]     |
[INFO] [stdout] 211 |       try!(self.register_interest_in_writing(event_loop, token))
[INFO] [stdout]     |       ^^^
[INFO] [stdout]     |
[INFO] [stdout]     = note: `#[warn(deprecated)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: anonymous parameters are deprecated and will be removed in the next edition.
[INFO] [stdout]   --> src/codec.rs:54:35
[INFO] [stdout]    |
[INFO] [stdout] 54 |   fn encode(&mut self, frame: &F, &mut [u8]) -> EncodingResult;
[INFO] [stdout]    |                                   ^^^^^^^^^ help: try naming the parameter or explicitly ignoring it: `_: &mut [u8]`
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(anonymous_parameters)]` on by default
[INFO] [stdout]    = warning: this is accepted in the current edition (Rust 2015) but is a hard error in Rust 2018!
[INFO] [stdout]    = note: for more information, see issue #41686 <https://github.com/rust-lang/rust/issues/41686>
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: anonymous parameters are deprecated and will be removed in the next edition.
[INFO] [stdout]   --> src/codec.rs:55:24
[INFO] [stdout]    |
[INFO] [stdout] 55 |   fn decode(&mut self, &[u8]) -> DecodingResult<F>;
[INFO] [stdout]    |                        ^^^^^ help: try naming the parameter or explicitly ignoring it: `_: &[u8]`
[INFO] [stdout]    |
[INFO] [stdout]    = warning: this is accepted in the current edition (Rust 2015) but is a hard error in Rust 2018!
[INFO] [stdout]    = note: for more information, see issue #41686 <https://github.com/rust-lang/rust/issues/41686>
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: anonymous parameters are deprecated and will be removed in the next edition.
[INFO] [stdout]  --> src/evented_byte_stream.rs:7:34
[INFO] [stdout]   |
[INFO] [stdout] 7 |   fn read_into_buffer(&mut self, &mut Buffer) -> io::Result<usize>;
[INFO] [stdout]   |                                  ^^^^^^^^^^^ help: try naming the parameter or explicitly ignoring it: `_: &mut Buffer`
[INFO] [stdout]   |
[INFO] [stdout]   = warning: this is accepted in the current edition (Rust 2015) but is a hard error in Rust 2018!
[INFO] [stdout]   = note: for more information, see issue #41686 <https://github.com/rust-lang/rust/issues/41686>
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: anonymous parameters are deprecated and will be removed in the next edition.
[INFO] [stdout]  --> src/evented_byte_stream.rs:8:35
[INFO] [stdout]   |
[INFO] [stdout] 8 |   fn write_from_buffer(&mut self, &mut Buffer) -> io::Result<usize>;
[INFO] [stdout]   |                                   ^^^^^^^^^^^ help: try naming the parameter or explicitly ignoring it: `_: &mut Buffer`
[INFO] [stdout]   |
[INFO] [stdout]   = warning: this is accepted in the current edition (Rust 2015) but is a hard error in Rust 2018!
[INFO] [stdout]   = note: for more information, see issue #41686 <https://github.com/rust-lang/rust/issues/41686>
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: anonymous parameters are deprecated and will be removed in the next edition.
[INFO] [stdout]  --> src/settings.rs:5:23
[INFO] [stdout]   |
[INFO] [stdout] 5 |   fn set_option(self, T) -> T;
[INFO] [stdout]   |                       ^ help: try naming the parameter or explicitly ignoring it: `_: T`
[INFO] [stdout]   |
[INFO] [stdout]   = warning: this is accepted in the current edition (Rust 2015) but is a hard error in Rust 2018!
[INFO] [stdout]   = note: for more information, see issue #41686 <https://github.com/rust-lang/rust/issues/41686>
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: use of deprecated macro `try`: use the `?` operator instead
[INFO] [stdout]    --> src/evented_frame_stream.rs:211:7
[INFO] [stdout]     |
[INFO] [stdout] 211 |       try!(self.register_interest_in_writing(event_loop, token))
[INFO] [stdout]     |       ^^^
[INFO] [stdout]     |
[INFO] [stdout]     = note: `#[warn(deprecated)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: anonymous parameters are deprecated and will be removed in the next edition.
[INFO] [stdout]   --> src/codec.rs:54:35
[INFO] [stdout]    |
[INFO] [stdout] 54 |   fn encode(&mut self, frame: &F, &mut [u8]) -> EncodingResult;
[INFO] [stdout]    |                                   ^^^^^^^^^ help: try naming the parameter or explicitly ignoring it: `_: &mut [u8]`
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(anonymous_parameters)]` on by default
[INFO] [stdout]    = warning: this is accepted in the current edition (Rust 2015) but is a hard error in Rust 2018!
[INFO] [stdout]    = note: for more information, see issue #41686 <https://github.com/rust-lang/rust/issues/41686>
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: anonymous parameters are deprecated and will be removed in the next edition.
[INFO] [stdout]   --> src/codec.rs:55:24
[INFO] [stdout]    |
[INFO] [stdout] 55 |   fn decode(&mut self, &[u8]) -> DecodingResult<F>;
[INFO] [stdout]    |                        ^^^^^ help: try naming the parameter or explicitly ignoring it: `_: &[u8]`
[INFO] [stdout]    |
[INFO] [stdout]    = warning: this is accepted in the current edition (Rust 2015) but is a hard error in Rust 2018!
[INFO] [stdout]    = note: for more information, see issue #41686 <https://github.com/rust-lang/rust/issues/41686>
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: anonymous parameters are deprecated and will be removed in the next edition.
[INFO] [stdout]  --> src/evented_byte_stream.rs:7:34
[INFO] [stdout]   |
[INFO] [stdout] 7 |   fn read_into_buffer(&mut self, &mut Buffer) -> io::Result<usize>;
[INFO] [stdout]   |                                  ^^^^^^^^^^^ help: try naming the parameter or explicitly ignoring it: `_: &mut Buffer`
[INFO] [stdout]   |
[INFO] [stdout]   = warning: this is accepted in the current edition (Rust 2015) but is a hard error in Rust 2018!
[INFO] [stdout]   = note: for more information, see issue #41686 <https://github.com/rust-lang/rust/issues/41686>
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: anonymous parameters are deprecated and will be removed in the next edition.
[INFO] [stdout]  --> src/evented_byte_stream.rs:8:35
[INFO] [stdout]   |
[INFO] [stdout] 8 |   fn write_from_buffer(&mut self, &mut Buffer) -> io::Result<usize>;
[INFO] [stdout]   |                                   ^^^^^^^^^^^ help: try naming the parameter or explicitly ignoring it: `_: &mut Buffer`
[INFO] [stdout]   |
[INFO] [stdout]   = warning: this is accepted in the current edition (Rust 2015) but is a hard error in Rust 2018!
[INFO] [stdout]   = note: for more information, see issue #41686 <https://github.com/rust-lang/rust/issues/41686>
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: anonymous parameters are deprecated and will be removed in the next edition.
[INFO] [stdout]  --> src/settings.rs:5:23
[INFO] [stdout]   |
[INFO] [stdout] 5 |   fn set_option(self, T) -> T;
[INFO] [stdout]   |                       ^ help: try naming the parameter or explicitly ignoring it: `_: T`
[INFO] [stdout]   |
[INFO] [stdout]   = warning: this is accepted in the current edition (Rust 2015) but is a hard error in Rust 2018!
[INFO] [stdout]   = note: for more information, see issue #41686 <https://github.com/rust-lang/rust/issues/41686>
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused import: `Evented`
[INFO] [stdout]  --> src/protocol_engine.rs:1:11
[INFO] [stdout]   |
[INFO] [stdout] 1 | use mio::{Evented, EventSet, PollOpt, Token};
[INFO] [stdout]   |           ^^^^^^^
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(unused_imports)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused import: `Recycleable`
[INFO] [stdout]  --> src/protocol_engine.rs:5:23
[INFO] [stdout]   |
[INFO] [stdout] 5 | use lifeguard::{self, Recycleable, Pool, StartingSize, MaxSize, Supplier};
[INFO] [stdout]   |                       ^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused import: `Read`
[INFO] [stdout]  --> src/protocol_engine.rs:8:21
[INFO] [stdout]   |
[INFO] [stdout] 8 | use std::io::{self, Read, Write};
[INFO] [stdout]   |                     ^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused import: `Write`
[INFO] [stdout]  --> src/protocol_engine.rs:8:27
[INFO] [stdout]   |
[INFO] [stdout] 8 | use std::io::{self, Read, Write};
[INFO] [stdout]   |                           ^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: variable does not need to be mutable
[INFO] [stdout]    --> src/evented_frame_stream.rs:215:9
[INFO] [stdout]     |
[INFO] [stdout] 215 |     let mut outbox = self.outbox(outbox_pool);
[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/protocol_engine.rs:131:12
[INFO] [stdout]     |
[INFO] [stdout] 131 |        let mut stream_session: &mut StreamSession<P> = stream_session.unwrap();
[INFO] [stdout]     |            ----^^^^^^^^^^^^^^
[INFO] [stdout]     |            |
[INFO] [stdout]     |            help: remove this `mut`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: variable does not need to be mutable
[INFO] [stdout]    --> src/protocol_engine.rs:133:13
[INFO] [stdout]     |
[INFO] [stdout] 133 |        let (mut efs, mut session) = stream_session.components();
[INFO] [stdout]     |             ----^^^
[INFO] [stdout]     |             |
[INFO] [stdout]     |             help: remove this `mut`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: variable does not need to be mutable
[INFO] [stdout]    --> src/protocol_engine.rs:133:22
[INFO] [stdout]     |
[INFO] [stdout] 133 |        let (mut efs, mut session) = stream_session.components();
[INFO] [stdout]     |                      ----^^^^^^^
[INFO] [stdout]     |                      |
[INFO] [stdout]     |                      help: remove this `mut`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: variable does not need to be mutable
[INFO] [stdout]    --> src/protocol_engine.rs:215:17
[INFO] [stdout]     |
[INFO] [stdout] 215 |             let mut stream_session: &mut StreamSession<P> = stream_session.unwrap();
[INFO] [stdout]     |                 ----^^^^^^^^^^^^^^
[INFO] [stdout]     |                 |
[INFO] [stdout]     |                 help: remove this `mut`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: variable does not need to be mutable
[INFO] [stdout]    --> src/protocol_engine.rs:216:18
[INFO] [stdout]     |
[INFO] [stdout] 216 |             let (mut efs, mut session) = stream_session.components();
[INFO] [stdout]     |                  ----^^^
[INFO] [stdout]     |                  |
[INFO] [stdout]     |                  help: remove this `mut`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused import: `Evented`
[INFO] [stdout]  --> src/protocol_engine.rs:1:11
[INFO] [stdout]   |
[INFO] [stdout] 1 | use mio::{Evented, EventSet, PollOpt, Token};
[INFO] [stdout]   |           ^^^^^^^
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(unused_imports)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: variable does not need to be mutable
[INFO] [stdout]    --> src/protocol_engine.rs:216:27
[INFO] [stdout]     |
[INFO] [stdout] 216 |             let (mut efs, mut session) = stream_session.components();
[INFO] [stdout]     |                           ----^^^^^^^
[INFO] [stdout]     |                           |
[INFO] [stdout]     |                           help: remove this `mut`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused import: `Recycleable`
[INFO] [stdout]  --> src/protocol_engine.rs:5:23
[INFO] [stdout]   |
[INFO] [stdout] 5 | use lifeguard::{self, Recycleable, Pool, StartingSize, MaxSize, Supplier};
[INFO] [stdout]   |                       ^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused import: `Read`
[INFO] [stdout]  --> src/protocol_engine.rs:8:21
[INFO] [stdout]   |
[INFO] [stdout] 8 | use std::io::{self, Read, Write};
[INFO] [stdout]   |                     ^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused import: `Write`
[INFO] [stdout]  --> src/protocol_engine.rs:8:27
[INFO] [stdout]   |
[INFO] [stdout] 8 | use std::io::{self, Read, Write};
[INFO] [stdout]   |                           ^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: variable does not need to be mutable
[INFO] [stdout]    --> src/evented_frame_stream.rs:215:9
[INFO] [stdout]     |
[INFO] [stdout] 215 |     let mut outbox = self.outbox(outbox_pool);
[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/protocol_engine.rs:531:26
[INFO] [stdout]     |
[INFO] [stdout] 531 |     let (codec, _stream, mut write_buffer, outbox) = efs.writing_toolset(buffer_pool, outbox_pool);
[INFO] [stdout]     |                          ----^^^^^^^^^^^^
[INFO] [stdout]     |                          |
[INFO] [stdout]     |                          help: remove this `mut`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: variable does not need to be mutable
[INFO] [stdout]    --> src/protocol_engine.rs:131:12
[INFO] [stdout]     |
[INFO] [stdout] 131 |        let mut stream_session: &mut StreamSession<P> = stream_session.unwrap();
[INFO] [stdout]     |            ----^^^^^^^^^^^^^^
[INFO] [stdout]     |            |
[INFO] [stdout]     |            help: remove this `mut`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: variable does not need to be mutable
[INFO] [stdout]    --> src/protocol_engine.rs:133:13
[INFO] [stdout]     |
[INFO] [stdout] 133 |        let (mut efs, mut session) = stream_session.components();
[INFO] [stdout]     |             ----^^^
[INFO] [stdout]     |             |
[INFO] [stdout]     |             help: remove this `mut`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: variable does not need to be mutable
[INFO] [stdout]    --> src/protocol_engine.rs:133:22
[INFO] [stdout]     |
[INFO] [stdout] 133 |        let (mut efs, mut session) = stream_session.components();
[INFO] [stdout]     |                      ----^^^^^^^
[INFO] [stdout]     |                      |
[INFO] [stdout]     |                      help: remove this `mut`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: variable does not need to be mutable
[INFO] [stdout]    --> src/protocol_engine.rs:215:17
[INFO] [stdout]     |
[INFO] [stdout] 215 |             let mut stream_session: &mut StreamSession<P> = stream_session.unwrap();
[INFO] [stdout]     |                 ----^^^^^^^^^^^^^^
[INFO] [stdout]     |                 |
[INFO] [stdout]     |                 help: remove this `mut`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: variable does not need to be mutable
[INFO] [stdout]    --> src/protocol_engine.rs:216:18
[INFO] [stdout]     |
[INFO] [stdout] 216 |             let (mut efs, mut session) = stream_session.components();
[INFO] [stdout]     |                  ----^^^
[INFO] [stdout]     |                  |
[INFO] [stdout]     |                  help: remove this `mut`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: variable does not need to be mutable
[INFO] [stdout]    --> src/protocol_engine.rs:216:27
[INFO] [stdout]     |
[INFO] [stdout] 216 |             let (mut efs, mut session) = stream_session.components();
[INFO] [stdout]     |                           ----^^^^^^^
[INFO] [stdout]     |                           |
[INFO] [stdout]     |                           help: remove this `mut`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: variable does not need to be mutable
[INFO] [stdout]    --> src/protocol_engine.rs:531:26
[INFO] [stdout]     |
[INFO] [stdout] 531 |     let (codec, _stream, mut write_buffer, outbox) = efs.writing_toolset(buffer_pool, outbox_pool);
[INFO] [stdout]     |                          ----^^^^^^^^^^^^
[INFO] [stdout]     |                          |
[INFO] [stdout]     |                          help: remove this `mut`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 18 warnings emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 18 warnings emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]     Finished dev [unoptimized + debuginfo] target(s) in 3.94s
[INFO] running `Command { std: "docker" "inspect" "399cf46cf75e6b4d126a1bcdbac617cc9f4ac39cc3ef152f65e18b686bdc0cc4", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "399cf46cf75e6b4d126a1bcdbac617cc9f4ac39cc3ef152f65e18b686bdc0cc4", kill_on_drop: false }`
[INFO] [stdout] 399cf46cf75e6b4d126a1bcdbac617cc9f4ac39cc3ef152f65e18b686bdc0cc4
