[INFO] cloning repository https://github.com/zhangsoledad/tokio-playground
[INFO] running `Command { std: "git" "-c" "credential.helper=" "-c" "credential.helper=/workspace/cargo-home/bin/git-credential-null" "clone" "--bare" "https://github.com/zhangsoledad/tokio-playground" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fzhangsoledad%2Ftokio-playground", kill_on_drop: false }`
[INFO] [stderr] Cloning into bare repository '/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fzhangsoledad%2Ftokio-playground'...
[INFO] running `Command { std: "git" "rev-parse" "HEAD", kill_on_drop: false }`
[INFO] [stdout] 40cc5ce61b1245020ae8e27a45ce0e57ab55e1cd
[INFO] testing zhangsoledad/tokio-playground against 1.55.0 for beta-1.56-1
[INFO] running `Command { std: "git" "clone" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fzhangsoledad%2Ftokio-playground" "/workspace/builds/worker-7/source", kill_on_drop: false }`
[INFO] [stderr] Cloning into '/workspace/builds/worker-7/source'...
[INFO] [stderr] done.
[INFO] validating manifest of git repo https://github.com/zhangsoledad/tokio-playground 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 git repo https://github.com/zhangsoledad/tokio-playground
[INFO] finished tweaking git repo https://github.com/zhangsoledad/tokio-playground
[INFO] tweaked toml for git repo https://github.com/zhangsoledad/tokio-playground written to /workspace/builds/worker-7/source/Cargo.toml
[INFO] crate git repo https://github.com/zhangsoledad/tokio-playground already has a lockfile, it will not be regenerated
[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] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-7/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-7/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] 67d05be3001efea2ea985dc39d6eca5aefdc4d6e7a2361060c69da103609bbc5
[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" "67d05be3001efea2ea985dc39d6eca5aefdc4d6e7a2361060c69da103609bbc5", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "67d05be3001efea2ea985dc39d6eca5aefdc4d6e7a2361060c69da103609bbc5", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "67d05be3001efea2ea985dc39d6eca5aefdc4d6e7a2361060c69da103609bbc5", kill_on_drop: false }`
[INFO] [stdout] 67d05be3001efea2ea985dc39d6eca5aefdc4d6e7a2361060c69da103609bbc5
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-7/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-7/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" "build" "--frozen" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] 937b4b56d482e647ee6dbe5cc509c081787027d060953b8ccb7c33526483369c
[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" "937b4b56d482e647ee6dbe5cc509c081787027d060953b8ccb7c33526483369c", kill_on_drop: false }`
[INFO] [stderr]    Compiling proc-macro2 v1.0.13
[INFO] [stderr]    Compiling syn v1.0.22
[INFO] [stderr]    Compiling arc-swap v0.4.6
[INFO] [stderr]    Compiling pin-project-lite v0.1.5
[INFO] [stderr]    Compiling libc v0.2.70
[INFO] [stderr]    Compiling net2 v0.2.34
[INFO] [stderr]    Compiling iovec v0.1.4
[INFO] [stderr]    Compiling signal-hook-registry v1.2.0
[INFO] [stderr]    Compiling num_cpus v1.13.0
[INFO] [stderr]    Compiling mio v0.6.22
[INFO] [stderr]    Compiling quote v1.0.6
[INFO] [stderr]    Compiling mio-uds v0.6.8
[INFO] [stderr]    Compiling tokio-macros v0.2.5
[INFO] [stderr]    Compiling tokio v0.2.21
[INFO] [stderr]    Compiling tokio-playground v0.1.0 (/opt/rustwide/workdir)
[INFO] [stderr]     Finished dev [unoptimized + debuginfo] target(s) in 18.80s
[INFO] running `Command { std: "docker" "inspect" "937b4b56d482e647ee6dbe5cc509c081787027d060953b8ccb7c33526483369c", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "937b4b56d482e647ee6dbe5cc509c081787027d060953b8ccb7c33526483369c", kill_on_drop: false }`
[INFO] [stdout] 937b4b56d482e647ee6dbe5cc509c081787027d060953b8ccb7c33526483369c
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-7/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-7/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" "test" "--frozen" "--no-run" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] e1c85d5f71da49ac5e441e01dd9057e77931beb00f3ce17d3acba9d51df911d3
[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" "e1c85d5f71da49ac5e441e01dd9057e77931beb00f3ce17d3acba9d51df911d3", kill_on_drop: false }`
[INFO] [stderr]    Compiling tokio-playground v0.1.0 (/opt/rustwide/workdir)
[INFO] [stdout] warning: unused `Result` that must be used
[INFO] [stdout]   --> examples/block_in_place.rs:28:13
[INFO] [stdout]    |
[INFO] [stdout] 28 |             t.await;
[INFO] [stdout]    |             ^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(unused_must_use)]` on by default
[INFO] [stdout]    = note: this `Result` may be an `Err` variant, which should be handled
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused `Result` that must be used
[INFO] [stdout]   --> examples/spawn_blocking.rs:29:13
[INFO] [stdout]    |
[INFO] [stdout] 29 |             t.await;
[INFO] [stdout]    |             ^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(unused_must_use)]` on by default
[INFO] [stdout]    = note: this `Result` may be an `Err` variant, which should be handled
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused `Result` that must be used
[INFO] [stdout]   --> examples/blocking.rs:27:13
[INFO] [stdout]    |
[INFO] [stdout] 27 |             t.await;
[INFO] [stdout]    |             ^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(unused_must_use)]` on by default
[INFO] [stdout]    = note: this `Result` may be an `Err` variant, which should be handled
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 1 warning emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 1 warning emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 1 warning emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]     Finished test [unoptimized + debuginfo] target(s) in 1.52s
[INFO] running `Command { std: "docker" "inspect" "e1c85d5f71da49ac5e441e01dd9057e77931beb00f3ce17d3acba9d51df911d3", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "e1c85d5f71da49ac5e441e01dd9057e77931beb00f3ce17d3acba9d51df911d3", kill_on_drop: false }`
[INFO] [stdout] e1c85d5f71da49ac5e441e01dd9057e77931beb00f3ce17d3acba9d51df911d3
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-7/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-7/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" "test" "--frozen", kill_on_drop: false }`
[INFO] [stdout] de93105455aa1685ebf98bd69ec86bd27ba9d41dae74955203840d8167add2f7
[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" "de93105455aa1685ebf98bd69ec86bd27ba9d41dae74955203840d8167add2f7", kill_on_drop: false }`
[INFO] [stderr] warning: unused `Result` that must be used
[INFO] [stderr]   --> examples/spawn_blocking.rs:29:13
[INFO] [stderr]    |
[INFO] [stderr] 29 |             t.await;
[INFO] [stderr]    |             ^^^^^^^^
[INFO] [stderr]    |
[INFO] [stderr]    = note: `#[warn(unused_must_use)]` on by default
[INFO] [stderr]    = note: this `Result` may be an `Err` variant, which should be handled
[INFO] [stderr] 
[INFO] [stderr] warning: unused `Result` that must be used
[INFO] [stderr]   --> examples/blocking.rs:27:13
[INFO] [stderr]    |
[INFO] [stderr] 27 |             t.await;
[INFO] [stderr]    |             ^^^^^^^^
[INFO] [stderr]    |
[INFO] [stderr]    = note: `#[warn(unused_must_use)]` on by default
[INFO] [stderr]    = note: this `Result` may be an `Err` variant, which should be handled
[INFO] [stderr] 
[INFO] [stderr] warning: unused `Result` that must be used
[INFO] [stderr]   --> examples/block_in_place.rs:28:13
[INFO] [stderr]    |
[INFO] [stderr] 28 |             t.await;
[INFO] [stderr]    |             ^^^^^^^^
[INFO] [stderr]    |
[INFO] [stderr]    = note: `#[warn(unused_must_use)]` on by default
[INFO] [stderr]    = note: this `Result` may be an `Err` variant, which should be handled
[INFO] [stderr] 
[INFO] [stderr] warning: `tokio-playground` (example "spawn_blocking") generated 1 warning
[INFO] [stderr] warning: `tokio-playground` (example "blocking") generated 1 warning
[INFO] [stderr] warning: `tokio-playground` (example "block_in_place") generated 1 warning
[INFO] [stderr]     Finished test [unoptimized + debuginfo] target(s) in 0.02s
[INFO] [stderr]      Running unittests (/opt/rustwide/target/debug/deps/tokio_playground-2cc752b17cb1e0cc)
[INFO] [stdout] 
[INFO] [stdout] running 0 tests
[INFO] [stdout] 
[INFO] [stdout] test result: ok. 0 passed; 0 failed; 0 ignored; 0 measured; 0 filtered out; finished in 0.00s
[INFO] [stdout] 
[INFO] [stderr]    Doc-tests tokio-playground
[INFO] [stdout] 
[INFO] [stdout] running 0 tests
[INFO] [stdout] 
[INFO] [stdout] test result: ok. 0 passed; 0 failed; 0 ignored; 0 measured; 0 filtered out; finished in 0.00s
[INFO] [stdout] 
[INFO] running `Command { std: "docker" "inspect" "de93105455aa1685ebf98bd69ec86bd27ba9d41dae74955203840d8167add2f7", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "de93105455aa1685ebf98bd69ec86bd27ba9d41dae74955203840d8167add2f7", kill_on_drop: false }`
[INFO] [stdout] de93105455aa1685ebf98bd69ec86bd27ba9d41dae74955203840d8167add2f7