[INFO] cloning repository https://github.com/ugoa/tcprs
[INFO] running `Command { std: "git" "-c" "credential.helper=" "-c" "credential.helper=/workspace/cargo-home/bin/git-credential-null" "clone" "--bare" "https://github.com/ugoa/tcprs" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fugoa%2Ftcprs", kill_on_drop: false }`
[INFO] [stderr] Cloning into bare repository '/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fugoa%2Ftcprs'...
[INFO] running `Command { std: "git" "rev-parse" "HEAD", kill_on_drop: false }`
[INFO] [stdout] 3b3fe0bf3b9513f9082a2603f644ca3ee33b34b3
[INFO] checking ugoa/tcprs against try#943e2200e35c3825486c4671b6cab0107a07f8c1 for pr-148952
[INFO] running `Command { std: "git" "clone" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fugoa%2Ftcprs" "/workspace/builds/worker-3-tc2/source", kill_on_drop: false }`
[INFO] [stderr] Cloning into '/workspace/builds/worker-3-tc2/source'...
[INFO] [stderr] done.
[INFO] started tweaking git repo https://github.com/ugoa/tcprs
[INFO] finished tweaking git repo https://github.com/ugoa/tcprs
[INFO] tweaked toml for git repo https://github.com/ugoa/tcprs written to /workspace/builds/worker-3-tc2/source/Cargo.toml
[INFO] validating manifest of git repo https://github.com/ugoa/tcprs on toolchain 943e2200e35c3825486c4671b6cab0107a07f8c1
[INFO] running `Command { std: CARGO_HOME="/workspace/cargo-home" RUSTUP_HOME="/workspace/rustup-home" "/workspace/cargo-home/bin/cargo" "+943e2200e35c3825486c4671b6cab0107a07f8c1" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }`
[INFO] crate git repo https://github.com/ugoa/tcprs already has a lockfile, it will not be regenerated
[INFO] running `Command { std: CARGO_HOME="/workspace/cargo-home" RUSTUP_HOME="/workspace/rustup-home" "/workspace/cargo-home/bin/cargo" "+943e2200e35c3825486c4671b6cab0107a07f8c1" "fetch" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] [stderr]     Blocking waiting for file lock on package cache
[INFO] [stderr]     Updating crates.io index
[INFO] [stderr]     Blocking waiting for file lock on package cache
[INFO] [stderr]  Downloading crates ...
[INFO] [stderr]   Downloaded tun-tap v0.1.2
[INFO] [stderr]   Downloaded net2 v0.2.34
[INFO] [stderr]   Downloaded hermit-abi v0.1.14
[INFO] [stderr]   Downloaded smallvec v0.6.13
[INFO] [stderr]   Downloaded parking_lot_core v0.6.2
[INFO] [stderr]   Downloaded memoffset v0.5.4
[INFO] [stderr]   Downloaded scoped-tls v0.1.2
[INFO] [stderr]   Downloaded tokio-uds v0.2.6
[INFO] [stderr]   Downloaded futures v0.1.29
[INFO] [stderr]   Downloaded tokio-core v0.1.17
[INFO] [stderr]   Downloaded mio v0.6.22
[INFO] [stderr]   Downloaded libc v0.2.71
[INFO] [stderr]   Downloaded etherparse v0.8.3
[INFO] [stderr]   Downloaded cc v1.0.56
[INFO] [stderr]   Downloaded crossbeam-deque v0.7.3
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-3-tc2/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-3-tc2/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@sha256:4848fb76d95f26979359cc7e45710b1dbc8f3acb7aeedee7c460d7702230f228" "/opt/rustwide/cargo-home/bin/cargo" "+943e2200e35c3825486c4671b6cab0107a07f8c1" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] af86e7a3349eca9fb4582c5c44db72e4ef49cf4cb9c8d3f84be54aeea44c8755
[INFO] running `Command { std: "docker" "start" "-a" "af86e7a3349eca9fb4582c5c44db72e4ef49cf4cb9c8d3f84be54aeea44c8755", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "af86e7a3349eca9fb4582c5c44db72e4ef49cf4cb9c8d3f84be54aeea44c8755", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "af86e7a3349eca9fb4582c5c44db72e4ef49cf4cb9c8d3f84be54aeea44c8755", kill_on_drop: false }`
[INFO] [stdout] af86e7a3349eca9fb4582c5c44db72e4ef49cf4cb9c8d3f84be54aeea44c8755
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-3-tc2/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-3-tc2/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" "RUSTDOCFLAGS=--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" "ghcr.io/rust-lang/crates-build-env/linux@sha256:4848fb76d95f26979359cc7e45710b1dbc8f3acb7aeedee7c460d7702230f228" "/opt/rustwide/cargo-home/bin/cargo" "+943e2200e35c3825486c4671b6cab0107a07f8c1" "check" "--frozen" "--all" "--all-targets" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] 19bd693bacf27ffd076770bbc20ba9674cc9de37bc4563121da74f056ada9cfc
[INFO] running `Command { std: "docker" "start" "-a" "19bd693bacf27ffd076770bbc20ba9674cc9de37bc4563121da74f056ada9cfc", kill_on_drop: false }`
[INFO] [stderr]    Compiling autocfg v1.0.0
[INFO] [stderr]    Compiling libc v0.2.71
[INFO] [stderr]    Compiling maybe-uninit v2.0.0
[INFO] [stderr]     Checking futures v0.1.29
[INFO] [stderr]    Compiling log v0.4.8
[INFO] [stderr]    Compiling byteorder v1.3.4
[INFO] [stderr]     Checking scopeguard v1.1.0
[INFO] [stderr]    Compiling cc v1.0.56
[INFO] [stderr]     Checking scoped-tls v0.1.2
[INFO] [stderr]    Compiling parking_lot_core v0.6.2
[INFO] [stderr]    Compiling parking_lot v0.9.0
[INFO] [stderr]     Checking lock_api v0.3.4
[INFO] [stderr]    Compiling crossbeam-utils v0.7.2
[INFO] [stderr]    Compiling memoffset v0.5.4
[INFO] [stderr]    Compiling crossbeam-epoch v0.8.2
[INFO] [stderr]     Checking smallvec v0.6.13
[INFO] [stderr]    Compiling tun-tap v0.1.2
[INFO] [stderr]     Checking etherparse v0.8.3
[INFO] [stderr]     Checking iovec v0.1.4
[INFO] [stderr]     Checking num_cpus v1.13.0
[INFO] [stderr]     Checking net2 v0.2.34
[INFO] [stderr]     Checking crossbeam-queue v0.2.3
[INFO] [stderr]     Checking bytes v0.4.12
[INFO] [stderr]     Checking mio v0.6.22
[INFO] [stderr]     Checking tokio-executor v0.1.10
[INFO] [stderr]     Checking tokio-sync v0.1.8
[INFO] [stderr]     Checking tokio-timer v0.2.13
[INFO] [stderr]     Checking tokio-current-thread v0.1.7
[INFO] [stderr]     Checking crossbeam-deque v0.7.3
[INFO] [stderr]     Checking tokio-io v0.1.13
[INFO] [stderr]     Checking tokio-threadpool v0.1.18
[INFO] [stderr]     Checking mio-uds v0.6.8
[INFO] [stderr]     Checking tokio-reactor v0.1.12
[INFO] [stderr]     Checking tokio-codec v0.1.2
[INFO] [stderr]     Checking tokio-fs v0.1.7
[INFO] [stderr]     Checking tokio-tcp v0.1.4
[INFO] [stderr]     Checking tokio-udp v0.1.6
[INFO] [stderr]     Checking tokio-uds v0.2.6
[INFO] [stderr]     Checking tokio v0.1.22
[INFO] [stderr]     Checking tokio-core v0.1.17
[INFO] [stderr]     Checking tcprs v0.1.0 (/opt/rustwide/workdir)
[INFO] [stdout] warning: variable does not need to be mutable
[INFO] [stdout]   --> src/tcp.rs:58:13
[INFO] [stdout]    |
[INFO] [stdout] 58 |         let mut buf = [0u8; 1500];
[INFO] [stdout]    |             ----^^^
[INFO] [stdout]    |             |
[INFO] [stdout]    |             help: remove this `mut`
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(unused_mut)]` (part of `#[warn(unused)]`) on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `data`
[INFO] [stdout]   --> src/tcp.rs:56:9
[INFO] [stdout]    |
[INFO] [stdout] 56 |         data: &'a [u8],
[INFO] [stdout]    |         ^^^^ help: if this is intentional, prefix it with an underscore: `_data`
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(unused_variables)]` (part of `#[warn(unused)]`) on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `buf`
[INFO] [stdout]   --> src/tcp.rs:58:13
[INFO] [stdout]    |
[INFO] [stdout] 58 |         let mut buf = [0u8; 1500];
[INFO] [stdout]    |             ^^^^^^^ help: if this is intentional, prefix it with an underscore: `_buf`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `iph`
[INFO] [stdout]    --> src/tcp.rs:157:9
[INFO] [stdout]     |
[INFO] [stdout] 157 |         iph: etherparse::Ipv4HeaderSlice<'a>,
[INFO] [stdout]     |         ^^^ help: if this is intentional, prefix it with an underscore: `_iph`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: variable does not need to be mutable
[INFO] [stdout]   --> src/tcp.rs:58:13
[INFO] [stdout]    |
[INFO] [stdout] 58 |         let mut buf = [0u8; 1500];
[INFO] [stdout]    |             ----^^^
[INFO] [stdout]    |             |
[INFO] [stdout]    |             help: remove this `mut`
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(unused_mut)]` (part of `#[warn(unused)]`) on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `data`
[INFO] [stdout]   --> src/tcp.rs:56:9
[INFO] [stdout]    |
[INFO] [stdout] 56 |         data: &'a [u8],
[INFO] [stdout]    |         ^^^^ help: if this is intentional, prefix it with an underscore: `_data`
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(unused_variables)]` (part of `#[warn(unused)]`) on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `buf`
[INFO] [stdout]   --> src/tcp.rs:58:13
[INFO] [stdout]    |
[INFO] [stdout] 58 |         let mut buf = [0u8; 1500];
[INFO] [stdout]    |             ^^^^^^^ help: if this is intentional, prefix it with an underscore: `_buf`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `iph`
[INFO] [stdout]    --> src/tcp.rs:157:9
[INFO] [stdout]     |
[INFO] [stdout] 157 |         iph: etherparse::Ipv4HeaderSlice<'a>,
[INFO] [stdout]     |         ^^^ help: if this is intentional, prefix it with an underscore: `_iph`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: fields `wnd`, `up`, `wl1`, `wl2`, and `iss` are never read
[INFO] [stdout]   --> src/tcp.rs:33:5
[INFO] [stdout]    |
[INFO] [stdout] 27 | struct SendSequenceSpace {
[INFO] [stdout]    |        ----------------- fields in this struct
[INFO] [stdout] ...
[INFO] [stdout] 33 |     wnd: u16,
[INFO] [stdout]    |     ^^^
[INFO] [stdout] 34 |     /// send urgent pointer
[INFO] [stdout] 35 |     up: bool,
[INFO] [stdout]    |     ^^
[INFO] [stdout] 36 |     /// segment sequence number used for last window update
[INFO] [stdout] 37 |     wl1: usize,
[INFO] [stdout]    |     ^^^
[INFO] [stdout] 38 |     /// segment acknowledgment number used for last window update
[INFO] [stdout] 39 |     wl2: usize,
[INFO] [stdout]    |     ^^^
[INFO] [stdout] 40 |     /// initial send sequence number
[INFO] [stdout] 41 |     iss: u32,
[INFO] [stdout]    |     ^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(dead_code)]` (part of `#[warn(unused)]`) on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: fields `up` and `irs` are never read
[INFO] [stdout]   --> src/tcp.rs:47:5
[INFO] [stdout]    |
[INFO] [stdout] 44 | struct RecvSequenceSpace {
[INFO] [stdout]    |        ----------------- fields in this struct
[INFO] [stdout] ...
[INFO] [stdout] 47 |     up: bool,
[INFO] [stdout]    |     ^^
[INFO] [stdout] 48 |     irs: u32,
[INFO] [stdout]    |     ^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: fields `wnd`, `up`, `wl1`, `wl2`, and `iss` are never read
[INFO] [stdout]   --> src/tcp.rs:33:5
[INFO] [stdout]    |
[INFO] [stdout] 27 | struct SendSequenceSpace {
[INFO] [stdout]    |        ----------------- fields in this struct
[INFO] [stdout] ...
[INFO] [stdout] 33 |     wnd: u16,
[INFO] [stdout]    |     ^^^
[INFO] [stdout] 34 |     /// send urgent pointer
[INFO] [stdout] 35 |     up: bool,
[INFO] [stdout]    |     ^^
[INFO] [stdout] 36 |     /// segment sequence number used for last window update
[INFO] [stdout] 37 |     wl1: usize,
[INFO] [stdout]    |     ^^^
[INFO] [stdout] 38 |     /// segment acknowledgment number used for last window update
[INFO] [stdout] 39 |     wl2: usize,
[INFO] [stdout]    |     ^^^
[INFO] [stdout] 40 |     /// initial send sequence number
[INFO] [stdout] 41 |     iss: u32,
[INFO] [stdout]    |     ^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(dead_code)]` (part of `#[warn(unused)]`) on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: fields `up` and `irs` are never read
[INFO] [stdout]   --> src/tcp.rs:47:5
[INFO] [stdout]    |
[INFO] [stdout] 44 | struct RecvSequenceSpace {
[INFO] [stdout]    |        ----------------- fields in this struct
[INFO] [stdout] ...
[INFO] [stdout] 47 |     up: bool,
[INFO] [stdout]    |     ^^
[INFO] [stdout] 48 |     irs: u32,
[INFO] [stdout]    |     ^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused `Result` that must be used
[INFO] [stdout]    --> src/tcp.rs:132:9
[INFO] [stdout]     |
[INFO] [stdout] 132 |         self.ip.set_payload_len(size);
[INFO] [stdout]     |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout]     |
[INFO] [stdout]     = note: this `Result` may be an `Err` variant, which should be handled
[INFO] [stdout]     = note: `#[warn(unused_must_use)]` (part of `#[warn(unused)]`) on by default
[INFO] [stdout] help: use `let _ = ...` to ignore the resulting value
[INFO] [stdout]     |
[INFO] [stdout] 132 |         let _ = self.ip.set_payload_len(size);
[INFO] [stdout]     |         +++++++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused `Result` that must be used
[INFO] [stdout]    --> src/tcp.rs:136:9
[INFO] [stdout]     |
[INFO] [stdout] 136 |         self.ip.write(&mut unwritten);
[INFO] [stdout]     |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout]     |
[INFO] [stdout]     = note: this `Result` may be an `Err` variant, which should be handled
[INFO] [stdout] help: use `let _ = ...` to ignore the resulting value
[INFO] [stdout]     |
[INFO] [stdout] 136 |         let _ = self.ip.write(&mut unwritten);
[INFO] [stdout]     |         +++++++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused `Result` that must be used
[INFO] [stdout]    --> src/tcp.rs:137:9
[INFO] [stdout]     |
[INFO] [stdout] 137 |         self.tcp.write(&mut unwritten);
[INFO] [stdout]     |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout]     |
[INFO] [stdout]     = note: this `Result` may be an `Err` variant, which should be handled
[INFO] [stdout] help: use `let _ = ...` to ignore the resulting value
[INFO] [stdout]     |
[INFO] [stdout] 137 |         let _ = self.tcp.write(&mut unwritten);
[INFO] [stdout]     |         +++++++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused return value of `core::num::<impl u32>::wrapping_add` that must be used
[INFO] [stdout]    --> src/tcp.rs:140:9
[INFO] [stdout]     |
[INFO] [stdout] 140 |         self.send.nxt.wrapping_add(payload_bytes as u32);
[INFO] [stdout]     |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout]     |
[INFO] [stdout]     = note: this returns the result of the operation, without modifying the original
[INFO] [stdout] help: use `let _ = ...` to ignore the resulting value
[INFO] [stdout]     |
[INFO] [stdout] 140 |         let _ = self.send.nxt.wrapping_add(payload_bytes as u32);
[INFO] [stdout]     |         +++++++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused `Result` that must be used
[INFO] [stdout]    --> src/tcp.rs:168:17
[INFO] [stdout]     |
[INFO] [stdout] 168 |                 self.send_rst(nic);
[INFO] [stdout]     |                 ^^^^^^^^^^^^^^^^^^
[INFO] [stdout]     |
[INFO] [stdout]     = note: this `Result` may be an `Err` variant, which should be handled
[INFO] [stdout] help: use `let _ = ...` to ignore the resulting value
[INFO] [stdout]     |
[INFO] [stdout] 168 |                 let _ = self.send_rst(nic);
[INFO] [stdout]     |                 +++++++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused `Result` that must be used
[INFO] [stdout]    --> src/tcp.rs:132:9
[INFO] [stdout]     |
[INFO] [stdout] 132 |         self.ip.set_payload_len(size);
[INFO] [stdout]     |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout]     |
[INFO] [stdout]     = note: this `Result` may be an `Err` variant, which should be handled
[INFO] [stdout]     = note: `#[warn(unused_must_use)]` (part of `#[warn(unused)]`) on by default
[INFO] [stdout] help: use `let _ = ...` to ignore the resulting value
[INFO] [stdout]     |
[INFO] [stdout] 132 |         let _ = self.ip.set_payload_len(size);
[INFO] [stdout]     |         +++++++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused `Result` that must be used
[INFO] [stdout]    --> src/tcp.rs:136:9
[INFO] [stdout]     |
[INFO] [stdout] 136 |         self.ip.write(&mut unwritten);
[INFO] [stdout]     |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout]     |
[INFO] [stdout]     = note: this `Result` may be an `Err` variant, which should be handled
[INFO] [stdout] help: use `let _ = ...` to ignore the resulting value
[INFO] [stdout]     |
[INFO] [stdout] 136 |         let _ = self.ip.write(&mut unwritten);
[INFO] [stdout]     |         +++++++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused `Result` that must be used
[INFO] [stdout]    --> src/tcp.rs:137:9
[INFO] [stdout]     |
[INFO] [stdout] 137 |         self.tcp.write(&mut unwritten);
[INFO] [stdout]     |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout]     |
[INFO] [stdout]     = note: this `Result` may be an `Err` variant, which should be handled
[INFO] [stdout] help: use `let _ = ...` to ignore the resulting value
[INFO] [stdout]     |
[INFO] [stdout] 137 |         let _ = self.tcp.write(&mut unwritten);
[INFO] [stdout]     |         +++++++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused return value of `core::num::<impl u32>::wrapping_add` that must be used
[INFO] [stdout]    --> src/tcp.rs:140:9
[INFO] [stdout]     |
[INFO] [stdout] 140 |         self.send.nxt.wrapping_add(payload_bytes as u32);
[INFO] [stdout]     |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout]     |
[INFO] [stdout]     = note: this returns the result of the operation, without modifying the original
[INFO] [stdout] help: use `let _ = ...` to ignore the resulting value
[INFO] [stdout]     |
[INFO] [stdout] 140 |         let _ = self.send.nxt.wrapping_add(payload_bytes as u32);
[INFO] [stdout]     |         +++++++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused `Result` that must be used
[INFO] [stdout]    --> src/tcp.rs:168:17
[INFO] [stdout]     |
[INFO] [stdout] 168 |                 self.send_rst(nic);
[INFO] [stdout]     |                 ^^^^^^^^^^^^^^^^^^
[INFO] [stdout]     |
[INFO] [stdout]     = note: this `Result` may be an `Err` variant, which should be handled
[INFO] [stdout] help: use `let _ = ...` to ignore the resulting value
[INFO] [stdout]     |
[INFO] [stdout] 168 |                 let _ = self.send_rst(nic);
[INFO] [stdout]     |                 +++++++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]     Finished `dev` profile [unoptimized + debuginfo] target(s) in 3.64s
[INFO] running `Command { std: "docker" "inspect" "19bd693bacf27ffd076770bbc20ba9674cc9de37bc4563121da74f056ada9cfc", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "19bd693bacf27ffd076770bbc20ba9674cc9de37bc4563121da74f056ada9cfc", kill_on_drop: false }`
[INFO] [stdout] 19bd693bacf27ffd076770bbc20ba9674cc9de37bc4563121da74f056ada9cfc
