[INFO] cloning repository https://github.com/Jasperav/returntypefuture
[INFO] running `Command { std: "git" "-c" "credential.helper=" "-c" "credential.helper=/workspace/cargo-home/bin/git-credential-null" "clone" "--bare" "https://github.com/Jasperav/returntypefuture" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2FJasperav%2Freturntypefuture", kill_on_drop: false }`
[INFO] [stderr] Cloning into bare repository '/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2FJasperav%2Freturntypefuture'...
[INFO] running `Command { std: "git" "rev-parse" "HEAD", kill_on_drop: false }`
[INFO] [stdout] a184611f9b62b959ac122961f5ee4d3b730c035f
[INFO] testing Jasperav/returntypefuture 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%2FJasperav%2Freturntypefuture" "/workspace/builds/worker-6/source", kill_on_drop: false }`
[INFO] [stderr] Cloning into '/workspace/builds/worker-6/source'...
[INFO] [stderr] done.
[INFO] validating manifest of git repo https://github.com/Jasperav/returntypefuture 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] started tweaking git repo https://github.com/Jasperav/returntypefuture
[INFO] finished tweaking git repo https://github.com/Jasperav/returntypefuture
[INFO] tweaked toml for git repo https://github.com/Jasperav/returntypefuture written to /workspace/builds/worker-6/source/Cargo.toml
[INFO] crate git repo https://github.com/Jasperav/returntypefuture 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]  Downloading crates ...
[INFO] [stderr]   Downloaded pin-project-internal v0.4.19
[INFO] [stderr]   Downloaded pin-project v0.4.19
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-6/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-6/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] [stdout] 9ff1d18e80651eb9f8d8068ef35849cb6b856b9da020a037c1d8295eddc6d248
[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" "9ff1d18e80651eb9f8d8068ef35849cb6b856b9da020a037c1d8295eddc6d248", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "9ff1d18e80651eb9f8d8068ef35849cb6b856b9da020a037c1d8295eddc6d248", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "9ff1d18e80651eb9f8d8068ef35849cb6b856b9da020a037c1d8295eddc6d248", kill_on_drop: false }`
[INFO] [stdout] 9ff1d18e80651eb9f8d8068ef35849cb6b856b9da020a037c1d8295eddc6d248
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-6/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-6/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] 38f37186edf3197d4031d7d73da276346729b978a0eec3301738916f44ba688e
[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" "38f37186edf3197d4031d7d73da276346729b978a0eec3301738916f44ba688e", kill_on_drop: false }`
[INFO] [stderr]    Compiling syn v1.0.30
[INFO] [stderr]    Compiling futures-channel v0.3.5
[INFO] [stderr]    Compiling input_buffer v0.3.1
[INFO] [stderr]    Compiling signal-hook-registry v1.2.0
[INFO] [stderr]    Compiling bytes v0.4.12
[INFO] [stderr]    Compiling openssl v0.10.29
[INFO] [stderr]    Compiling mio-uds v0.6.8
[INFO] [stderr]    Compiling ws v0.9.1
[INFO] [stderr]    Compiling native-tls v0.2.4
[INFO] [stderr]    Compiling tungstenite v0.10.1
[INFO] [stderr]    Compiling pin-project-internal v0.4.19
[INFO] [stderr]    Compiling futures-macro v0.3.5
[INFO] [stderr]    Compiling tokio-macros v0.2.5
[INFO] [stderr]    Compiling tokio v0.2.21
[INFO] [stderr]    Compiling pin-project v0.4.19
[INFO] [stderr]    Compiling futures-util v0.3.5
[INFO] [stderr]    Compiling futures-executor v0.3.5
[INFO] [stderr]    Compiling futures v0.3.5
[INFO] [stderr]    Compiling tokio-tungstenite v0.10.1
[INFO] [stderr]    Compiling returntypefuture v0.1.0 (/opt/rustwide/workdir)
[INFO] [stdout] warning: unused import: `Future`
[INFO] [stdout]   --> src/main.rs:28:24
[INFO] [stdout]    |
[INFO] [stdout] 28 | use futures::{pin_mut, Future};
[INFO] [stdout]    |                        ^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(unused_imports)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error[E0308]: mismatched types
[INFO] [stdout]   --> src/main.rs:82:1
[INFO] [stdout]    |
[INFO] [stdout] 82 | #[tokio::main]
[INFO] [stdout]    | ^^^^^^^^^^^^^^ expected enum `Result`, found opaque type
[INFO] [stdout] 83 | async fn main() -> Result<(), IoError> {
[INFO] [stdout]    |                    ------------------- expected `Result<(), std::io::Error>` because of return type
[INFO] [stdout] ...
[INFO] [stdout] 87 | async fn some_fn() -> Result<(), IoError> {
[INFO] [stdout]    |                       ------------------- checked the `Output` of this `async fn`, found opaque type
[INFO] [stdout]    |
[INFO] [stdout]    = note: while checking the return type of the `async fn`
[INFO] [stdout]    = note:     expected enum `Result<(), std::io::Error>`
[INFO] [stdout]            found opaque type `impl futures::Future`
[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] help: consider `await`ing on the `Future`
[INFO] [stdout]    |
[INFO] [stdout] 82 | #[tokio::main].await
[INFO] [stdout]    |               ^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error: aborting due to previous error; 1 warning emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] For more information about this error, try `rustc --explain E0308`.
[INFO] [stdout] 
[INFO] [stderr] error: could not compile `returntypefuture` due to 2 previous errors; 1 warning emitted
[INFO] running `Command { std: "docker" "inspect" "38f37186edf3197d4031d7d73da276346729b978a0eec3301738916f44ba688e", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "38f37186edf3197d4031d7d73da276346729b978a0eec3301738916f44ba688e", kill_on_drop: false }`
[INFO] [stdout] 38f37186edf3197d4031d7d73da276346729b978a0eec3301738916f44ba688e
