[INFO] cloning repository https://github.com/wowjack/pubsub-tasks
[INFO] running `Command { std: "git" "-c" "credential.helper=" "-c" "credential.helper=/workspace/cargo-home/bin/git-credential-null" "clone" "--bare" "https://github.com/wowjack/pubsub-tasks" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fwowjack%2Fpubsub-tasks", kill_on_drop: false }`
[INFO] [stderr] Cloning into bare repository '/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fwowjack%2Fpubsub-tasks'...
[INFO] running `Command { std: "git" "rev-parse" "HEAD", kill_on_drop: false }`
[INFO] [stdout] 76c794bfd0a7b151b13c7dc8d28cd6ef69b28bfd
[INFO] checking wowjack/pubsub-tasks against master#a26e97be8826d408309fffbd8168362365719f50 for pr-136776
[INFO] running `Command { std: "git" "clone" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fwowjack%2Fpubsub-tasks" "/workspace/builds/worker-4-tc1/source", kill_on_drop: false }`
[INFO] [stderr] Cloning into '/workspace/builds/worker-4-tc1/source'...
[INFO] [stderr] done.
[INFO] validating manifest of git repo https://github.com/wowjack/pubsub-tasks on toolchain a26e97be8826d408309fffbd8168362365719f50
[INFO] running `Command { std: CARGO_HOME="/workspace/cargo-home" RUSTUP_HOME="/workspace/rustup-home" "/workspace/cargo-home/bin/cargo" "+a26e97be8826d408309fffbd8168362365719f50" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }`
[INFO] started tweaking git repo https://github.com/wowjack/pubsub-tasks
[INFO] finished tweaking git repo https://github.com/wowjack/pubsub-tasks
[INFO] tweaked toml for git repo https://github.com/wowjack/pubsub-tasks written to /workspace/builds/worker-4-tc1/source/Cargo.toml
[INFO] crate git repo https://github.com/wowjack/pubsub-tasks 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" "+a26e97be8826d408309fffbd8168362365719f50" "fetch" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-4-tc1/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-4-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@sha256:3959728d45483eb673ba100a951a6b9f5012970368db2a9e08e0ac9b67c8a5ad" "/opt/rustwide/cargo-home/bin/cargo" "+a26e97be8826d408309fffbd8168362365719f50" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] ccbea8e977408ae669270e0bd7a3a74d92425b4da238d77e0fafad711c0124aa
[INFO] running `Command { std: "docker" "start" "-a" "ccbea8e977408ae669270e0bd7a3a74d92425b4da238d77e0fafad711c0124aa", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "ccbea8e977408ae669270e0bd7a3a74d92425b4da238d77e0fafad711c0124aa", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "ccbea8e977408ae669270e0bd7a3a74d92425b4da238d77e0fafad711c0124aa", kill_on_drop: false }`
[INFO] [stdout] ccbea8e977408ae669270e0bd7a3a74d92425b4da238d77e0fafad711c0124aa
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-4-tc1/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-4-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=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@sha256:3959728d45483eb673ba100a951a6b9f5012970368db2a9e08e0ac9b67c8a5ad" "/opt/rustwide/cargo-home/bin/cargo" "+a26e97be8826d408309fffbd8168362365719f50" "check" "--frozen" "--all" "--all-targets" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] 9ccca8ccc401b193ada6a91024d3a6136372c0414605ac2562edc1e316a59ef4
[INFO] running `Command { std: "docker" "start" "-a" "9ccca8ccc401b193ada6a91024d3a6136372c0414605ac2562edc1e316a59ef4", kill_on_drop: false }`
[INFO] [stderr]     Checking pubsub-tasks v0.1.0 (/opt/rustwide/workdir)
[INFO] [stdout] warning: unused import: `PubSubBroker`
[INFO] [stdout]  --> src/task3.rs:3:29
[INFO] [stdout]   |
[INFO] [stdout] 3 | use crate::task2::{Message, PubSubBroker};
[INFO] [stdout]   |                             ^^^^^^^^^^^^
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(unused_imports)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused import: `PubSubBroker`
[INFO] [stdout]  --> src/task3.rs:3:29
[INFO] [stdout]   |
[INFO] [stdout] 3 | use crate::task2::{Message, PubSubBroker};
[INFO] [stdout]   |                             ^^^^^^^^^^^^
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(unused_imports)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: struct `TopicManager` is never constructed
[INFO] [stdout]   --> src/task1.rs:12:12
[INFO] [stdout]    |
[INFO] [stdout] 12 | pub struct TopicManager {
[INFO] [stdout]    |            ^^^^^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(dead_code)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: methods `subscribe`, `unsubscribe`, and `get_subscribers` are never used
[INFO] [stdout]   --> src/task1.rs:17:12
[INFO] [stdout]    |
[INFO] [stdout] 15 | impl TopicManager {
[INFO] [stdout]    | ----------------- methods in this implementation
[INFO] [stdout] 16 |     /// Add a subscriber to the subscriber list for a topic
[INFO] [stdout] 17 |     pub fn subscribe(&mut self, topic: &TopicID, subscriber: ClientID) {
[INFO] [stdout]    |            ^^^^^^^^^
[INFO] [stdout] ...
[INFO] [stdout] 22 |     pub fn unsubscribe(&mut self, topic: &TopicID, subscriber: ClientID) {
[INFO] [stdout]    |            ^^^^^^^^^^^
[INFO] [stdout] ...
[INFO] [stdout] 29 |     pub fn get_subscribers(&self, topic: &TopicID) -> Vec<ClientID> {
[INFO] [stdout]    |            ^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: enum `Message` is never used
[INFO] [stdout]  --> src/task2.rs:9:10
[INFO] [stdout]   |
[INFO] [stdout] 9 | pub enum Message {
[INFO] [stdout]   |          ^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: struct `PubSubBroker` is never constructed
[INFO] [stdout]   --> src/task2.rs:41:12
[INFO] [stdout]    |
[INFO] [stdout] 41 | pub struct PubSubBroker {
[INFO] [stdout]    |            ^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: methods `handle_message` and `run` are never used
[INFO] [stdout]   --> src/task2.rs:46:12
[INFO] [stdout]    |
[INFO] [stdout] 45 | impl PubSubBroker {
[INFO] [stdout]    | ----------------- methods in this implementation
[INFO] [stdout] 46 |     pub fn handle_message(&mut self, message: Message) {
[INFO] [stdout]    |            ^^^^^^^^^^^^^^
[INFO] [stdout] ...
[INFO] [stdout] 71 |     pub fn run(mut self) {
[INFO] [stdout]    |            ^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: struct `Channel` is never constructed
[INFO] [stdout]   --> src/task3.rs:10:12
[INFO] [stdout]    |
[INFO] [stdout] 10 | pub struct Channel {
[INFO] [stdout]    |            ^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: associated items `send`, `receive`, and `new` are never used
[INFO] [stdout]   --> src/task3.rs:16:12
[INFO] [stdout]    |
[INFO] [stdout] 14 | impl Channel {
[INFO] [stdout]    | ------------ associated items in this implementation
[INFO] [stdout] 15 |     /// Send a Publish packet to recipient
[INFO] [stdout] 16 |     pub fn send(&self, message: Message) -> Result<(), String> {
[INFO] [stdout]    |            ^^^^
[INFO] [stdout] ...
[INFO] [stdout] 21 |     pub fn receive(&self) -> Result<Message, String> {
[INFO] [stdout]    |            ^^^^^^^
[INFO] [stdout] ...
[INFO] [stdout] 25 |     pub fn new() -> (Self, Self) {
[INFO] [stdout]    |            ^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: struct `TopicManager` is never constructed
[INFO] [stdout]   --> src/task1.rs:12:12
[INFO] [stdout]    |
[INFO] [stdout] 12 | pub struct TopicManager {
[INFO] [stdout]    |            ^^^^^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(dead_code)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: methods `subscribe`, `unsubscribe`, and `get_subscribers` are never used
[INFO] [stdout]   --> src/task1.rs:17:12
[INFO] [stdout]    |
[INFO] [stdout] 15 | impl TopicManager {
[INFO] [stdout]    | ----------------- methods in this implementation
[INFO] [stdout] 16 |     /// Add a subscriber to the subscriber list for a topic
[INFO] [stdout] 17 |     pub fn subscribe(&mut self, topic: &TopicID, subscriber: ClientID) {
[INFO] [stdout]    |            ^^^^^^^^^
[INFO] [stdout] ...
[INFO] [stdout] 22 |     pub fn unsubscribe(&mut self, topic: &TopicID, subscriber: ClientID) {
[INFO] [stdout]    |            ^^^^^^^^^^^
[INFO] [stdout] ...
[INFO] [stdout] 29 |     pub fn get_subscribers(&self, topic: &TopicID) -> Vec<ClientID> {
[INFO] [stdout]    |            ^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: enum `Message` is never used
[INFO] [stdout]  --> src/task2.rs:9:10
[INFO] [stdout]   |
[INFO] [stdout] 9 | pub enum Message {
[INFO] [stdout]   |          ^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: struct `PubSubBroker` is never constructed
[INFO] [stdout]   --> src/task2.rs:41:12
[INFO] [stdout]    |
[INFO] [stdout] 41 | pub struct PubSubBroker {
[INFO] [stdout]    |            ^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused `Result` that must be used
[INFO] [stdout]   --> src/task2.rs:57:21
[INFO] [stdout]    |
[INFO] [stdout] 57 |                     self.channel.send(publish);
[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)]` on by default
[INFO] [stdout] help: use `let _ = ...` to ignore the resulting value
[INFO] [stdout]    |
[INFO] [stdout] 57 |                     let _ = self.channel.send(publish);
[INFO] [stdout]    |                     +++++++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: methods `handle_message` and `run` are never used
[INFO] [stdout]   --> src/task2.rs:46:12
[INFO] [stdout]    |
[INFO] [stdout] 45 | impl PubSubBroker {
[INFO] [stdout]    | ----------------- methods in this implementation
[INFO] [stdout] 46 |     pub fn handle_message(&mut self, message: Message) {
[INFO] [stdout]    |            ^^^^^^^^^^^^^^
[INFO] [stdout] ...
[INFO] [stdout] 71 |     pub fn run(mut self) {
[INFO] [stdout]    |            ^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: struct `Channel` is never constructed
[INFO] [stdout]   --> src/task3.rs:10:12
[INFO] [stdout]    |
[INFO] [stdout] 10 | pub struct Channel {
[INFO] [stdout]    |            ^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: associated items `send`, `receive`, and `new` are never used
[INFO] [stdout]   --> src/task3.rs:16:12
[INFO] [stdout]    |
[INFO] [stdout] 14 | impl Channel {
[INFO] [stdout]    | ------------ associated items in this implementation
[INFO] [stdout] 15 |     /// Send a Publish packet to recipient
[INFO] [stdout] 16 |     pub fn send(&self, message: Message) -> Result<(), String> {
[INFO] [stdout]    |            ^^^^
[INFO] [stdout] ...
[INFO] [stdout] 21 |     pub fn receive(&self) -> Result<Message, String> {
[INFO] [stdout]    |            ^^^^^^^
[INFO] [stdout] ...
[INFO] [stdout] 25 |     pub fn new() -> (Self, Self) {
[INFO] [stdout]    |            ^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused `Result` that must be used
[INFO] [stdout]   --> src/task2.rs:57:21
[INFO] [stdout]    |
[INFO] [stdout] 57 |                     self.channel.send(publish);
[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)]` on by default
[INFO] [stdout] help: use `let _ = ...` to ignore the resulting value
[INFO] [stdout]    |
[INFO] [stdout] 57 |                     let _ = self.channel.send(publish);
[INFO] [stdout]    |                     +++++++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]     Finished `dev` profile [unoptimized + debuginfo] target(s) in 0.16s
[INFO] running `Command { std: "docker" "inspect" "9ccca8ccc401b193ada6a91024d3a6136372c0414605ac2562edc1e316a59ef4", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "9ccca8ccc401b193ada6a91024d3a6136372c0414605ac2562edc1e316a59ef4", kill_on_drop: false }`
[INFO] [stdout] 9ccca8ccc401b193ada6a91024d3a6136372c0414605ac2562edc1e316a59ef4