[INFO] cloning repository https://github.com/JettTech/rust-async-workshop
[INFO] running `Command { std: "git" "-c" "credential.helper=" "-c" "credential.helper=/workspace/cargo-home/bin/git-credential-null" "clone" "--bare" "https://github.com/JettTech/rust-async-workshop" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2FJettTech%2Frust-async-workshop", kill_on_drop: false }`
[INFO] [stderr] Cloning into bare repository '/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2FJettTech%2Frust-async-workshop'...
[INFO] running `Command { std: "git" "rev-parse" "HEAD", kill_on_drop: false }`
[INFO] [stdout] 81ee361f04c4fe1a3b7a0a1eb644a2f1a2cb1fc0
[INFO] testing JettTech/rust-async-workshop against beta-2021-08-01 for beta-1.55-1
[INFO] running `Command { std: "git" "clone" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2FJettTech%2Frust-async-workshop" "/workspace/builds/worker-3/source", kill_on_drop: false }`
[INFO] [stderr] Cloning into '/workspace/builds/worker-3/source'...
[INFO] [stderr] done.
[INFO] validating manifest of git repo https://github.com/JettTech/rust-async-workshop on toolchain beta-2021-08-01
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+beta-2021-08-01" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }`
[INFO] removed /workspace/builds/worker-3/source/.cargo/config
[INFO] removed /workspace/builds/worker-3/source/rust-toolchain
[INFO] started tweaking git repo https://github.com/JettTech/rust-async-workshop
[INFO] finished tweaking git repo https://github.com/JettTech/rust-async-workshop
[INFO] tweaked toml for git repo https://github.com/JettTech/rust-async-workshop written to /workspace/builds/worker-3/source/Cargo.toml
[INFO] crate git repo https://github.com/JettTech/rust-async-workshop already has a lockfile, it will not be regenerated
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+beta-2021-08-01" "fetch" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] [stderr]     Updating git repository `https://github.com/tokio-rs/tracing`
[INFO] [stderr]  Downloading crates ...
[INFO] [stderr]   Downloaded tokio-io v0.2.0-alpha.5
[INFO] [stderr]   Downloaded tokio-codec v0.2.0-alpha.5
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[INFO] [stderr]   Downloaded tracing-core v0.1.6
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[INFO] [stderr]   Downloaded pin-project-internal v0.4.0-alpha.11
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[INFO] [stderr]   Downloaded pin-project v0.4.0-alpha.11
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[INFO] [stderr]   Downloaded futures-util-preview v0.3.0-alpha.18
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[INFO] [stderr]   Downloaded tracing-attributes v0.1.3
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[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-3/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-3/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" "+beta-2021-08-01" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stderr] WARNING: Your kernel does not support swap limit capabilities or the cgroup is not mounted. Memory limited without swap.
[INFO] [stdout] daa1a830748b495bb30e6335c282273c9d8cc16cca9218f797be050c1221b7a6
[INFO] running `Command { std: "docker" "start" "-a" "daa1a830748b495bb30e6335c282273c9d8cc16cca9218f797be050c1221b7a6", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "daa1a830748b495bb30e6335c282273c9d8cc16cca9218f797be050c1221b7a6", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "daa1a830748b495bb30e6335c282273c9d8cc16cca9218f797be050c1221b7a6", kill_on_drop: false }`
[INFO] [stdout] daa1a830748b495bb30e6335c282273c9d8cc16cca9218f797be050c1221b7a6
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-3/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-3/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" "+beta-2021-08-01" "build" "--frozen" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] 3c99e8b36d86710f6d4aa6c805bbc7d2d39345826c9e6595f57803af6d58d976
[INFO] [stderr] WARNING: Your kernel does not support swap limit capabilities or the cgroup is not mounted. Memory limited without swap.
[INFO] running `Command { std: "docker" "start" "-a" "3c99e8b36d86710f6d4aa6c805bbc7d2d39345826c9e6595f57803af6d58d976", kill_on_drop: false }`
[INFO] [stderr]    Compiling syn v1.0.5
[INFO] [stderr]    Compiling futures-core-preview v0.3.0-alpha.18
[INFO] [stderr]    Compiling futures-io-preview v0.3.0-alpha.18
[INFO] [stderr]    Compiling pin-project-internal v0.4.0-alpha.11
[INFO] [stderr]    Compiling crossbeam-utils v0.6.6
[INFO] [stderr]    Compiling tracing-core v0.1.6
[INFO] [stderr]    Compiling thread_local v0.3.6
[INFO] [stderr]    Compiling regex-automata v0.1.8
[INFO] [stderr]    Compiling bytes v0.4.12
[INFO] [stderr]    Compiling mio v0.6.19
[INFO] [stderr]    Compiling clap v2.33.0
[INFO] [stderr]    Compiling futures-sink-preview v0.3.0-alpha.18
[INFO] [stderr]    Compiling regex v1.3.1
[INFO] [stderr]    Compiling futures-channel-preview v0.3.0-alpha.18
[INFO] [stderr]    Compiling tracing-log v0.1.0
[INFO] [stderr]    Compiling tokio-io v0.1.12
[INFO] [stderr]    Compiling crossbeam-epoch v0.7.2
[INFO] [stderr]    Compiling tokio-executor v0.1.8
[INFO] [stderr]    Compiling crossbeam-queue v0.1.2
[INFO] [stderr]    Compiling crossbeam-channel v0.3.9
[INFO] [stderr]    Compiling mio-uds v0.6.7
[INFO] [stderr]    Compiling futures-util-preview v0.3.0-alpha.18
[INFO] [stderr]    Compiling tokio-current-thread v0.1.6
[INFO] [stderr]    Compiling tokio-timer v0.2.11
[INFO] [stderr]    Compiling crossbeam-deque v0.7.1
[INFO] [stderr]    Compiling matchers v0.0.1
[INFO] [stderr]    Compiling tokio-reactor v0.1.9
[INFO] [stderr]    Compiling tokio-codec v0.1.1
[INFO] [stderr]    Compiling tokio-threadpool v0.1.15
[INFO] [stderr]    Compiling tokio-uds v0.2.5
[INFO] [stderr]    Compiling tokio-tcp v0.1.3
[INFO] [stderr]    Compiling tokio-udp v0.1.5
[INFO] [stderr]    Compiling tracing-subscriber v0.1.3
[INFO] [stderr]    Compiling tokio-fs v0.1.6
[INFO] [stderr]    Compiling tokio v0.1.22
[INFO] [stderr]    Compiling tokio-sync v0.2.0-alpha.5
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[INFO] [stderr]    Compiling proc-macro-error v0.2.6
[INFO] [stderr]    Compiling tracing-attributes v0.1.3
[INFO] [stderr]    Compiling tokio-macros v0.2.0-alpha.5
[INFO] [stderr]    Compiling structopt-derive v0.3.2
[INFO] [stderr]    Compiling tracing v0.1.9
[INFO] [stderr]    Compiling tokio-executor v0.2.0-alpha.5
[INFO] [stderr]    Compiling structopt v0.3.2
[INFO] [stderr]    Compiling pin-project v0.4.0-alpha.11
[INFO] [stderr]    Compiling tokio-io v0.2.0-alpha.5
[INFO] [stderr]    Compiling tokio-codec v0.2.0-alpha.5
[INFO] [stderr]    Compiling tokio-timer v0.3.0-alpha.5
[INFO] [stderr]    Compiling tokio-fs v0.2.0-alpha.5
[INFO] [stderr]    Compiling tokio-net v0.2.0-alpha.5
[INFO] [stderr]    Compiling tokio v0.2.0-alpha.5
[INFO] [stderr]    Compiling tracing-futures v0.0.1-alpha.2 (https://github.com/tokio-rs/tracing?rev=9f1126a00d105ff85f5b65fc6457699430b1bed4#9f1126a0)
[INFO] [stderr]    Compiling client v0.0.0 (/opt/rustwide/workdir/client)
[INFO] [stderr]    Compiling server v0.0.0 (/opt/rustwide/workdir/server)
[INFO] [stdout] warning: variable does not need to be mutable
[INFO] [stdout]   --> client/src/../solutions/client.rs:10:39
[INFO] [stdout]    |
[INFO] [stdout] 10 | pub async fn run_client(user: String, mut stream: TcpStream) -> Result<(), Error> {
[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] error[E0277]: the `?` operator can only be used in an async block that returns `Result` or `Option` (or another type that implements `FromResidual`)
[INFO] [stdout]    --> client/src/main.rs:31:48
[INFO] [stdout]     |
[INFO] [stdout] 25  | #[tokio::main]
[INFO] [stdout]     | -------------- this function should return `Result` or `Option` to accept `?`
[INFO] [stdout] ...
[INFO] [stdout] 31  |     let conn = TcpStream::connect(server).await?;
[INFO] [stdout]     |                                                ^ cannot use the `?` operator in an async block that returns `()`
[INFO] [stdout]     |
[INFO] [stdout]     = help: the trait `FromResidual<Result<Infallible, std::io::Error>>` is not implemented for `()`
[INFO] [stdout] note: required by `from_residual`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error[E0308]: mismatched types
[INFO] [stdout]   --> client/src/main.rs:25:1
[INFO] [stdout]    |
[INFO] [stdout] 25 | #[tokio::main]
[INFO] [stdout]    | ^^^^^^^^^^^^^^
[INFO] [stdout]    | |
[INFO] [stdout]    | expected enum `Result`, found `()`
[INFO] [stdout]    | help: try using a variant of the expected enum: `Ok(#[tokio::main])`
[INFO] [stdout] 26 | async fn main() -> Result<(), client::Error> {
[INFO] [stdout]    |                    ------------------------- expected `Result<(), Box<(dyn std::error::Error + 'static)>>` because of return type
[INFO] [stdout]    |
[INFO] [stdout]    = note:   expected enum `Result<(), Box<(dyn std::error::Error + 'static)>>`
[INFO] [stdout]            found unit type `()`
[INFO] [stdout]    = note: this error originates in the attribute macro `tokio::main` (in Nightly builds, run with -Z macro-backtrace for more info)
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error: aborting due to 2 previous errors; 1 warning emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] Some errors have detailed explanations: E0277, E0308.
[INFO] [stdout] 
[INFO] [stdout] For more information about an error, try `rustc --explain E0277`.
[INFO] [stdout] 
[INFO] [stderr] error: could not compile `client` due to 3 previous errors; 1 warning emitted
[INFO] [stderr] warning: build failed, waiting for other jobs to finish...
[INFO] [stderr] error: build failed
[INFO] running `Command { std: "docker" "inspect" "3c99e8b36d86710f6d4aa6c805bbc7d2d39345826c9e6595f57803af6d58d976", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "3c99e8b36d86710f6d4aa6c805bbc7d2d39345826c9e6595f57803af6d58d976", kill_on_drop: false }`
[INFO] [stdout] 3c99e8b36d86710f6d4aa6c805bbc7d2d39345826c9e6595f57803af6d58d976
