[INFO] cloning repository https://github.com/daogangtang/learn-tokio
[INFO] running `Command { std: "git" "-c" "credential.helper=" "-c" "credential.helper=/workspace/cargo-home/bin/git-credential-null" "clone" "--bare" "https://github.com/daogangtang/learn-tokio" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fdaogangtang%2Flearn-tokio", kill_on_drop: false }`
[INFO] [stderr] Cloning into bare repository '/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fdaogangtang%2Flearn-tokio'...
[INFO] running `Command { std: "git" "rev-parse" "HEAD", kill_on_drop: false }`
[INFO] [stdout] 98b13be0e474ffb1b6a4f84b3e9caa91d100296a
[INFO] testing daogangtang/learn-tokio against try#ce59db7a1b1b012fb2793c4641c1bdecad7a128b for pr-85530
[INFO] running `Command { std: "git" "clone" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fdaogangtang%2Flearn-tokio" "/workspace/builds/worker-0/source", kill_on_drop: false }`
[INFO] [stderr] Cloning into '/workspace/builds/worker-0/source'...
[INFO] [stderr] done.
[INFO] validating manifest of git repo https://github.com/daogangtang/learn-tokio on toolchain ce59db7a1b1b012fb2793c4641c1bdecad7a128b
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+ce59db7a1b1b012fb2793c4641c1bdecad7a128b" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }`
[INFO] started tweaking git repo https://github.com/daogangtang/learn-tokio
[INFO] finished tweaking git repo https://github.com/daogangtang/learn-tokio
[INFO] tweaked toml for git repo https://github.com/daogangtang/learn-tokio written to /workspace/builds/worker-0/source/Cargo.toml
[INFO] crate git repo https://github.com/daogangtang/learn-tokio already has a lockfile, it will not be regenerated
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+ce59db7a1b1b012fb2793c4641c1bdecad7a128b" "fetch" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] [stderr]     Blocking waiting for file lock on package cache
[INFO] [stderr]     Blocking waiting for file lock on package cache
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-0/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-0/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@sha256:20528e8c29e4536546f0102ce88568b16ea7538393a33fcca951030f7af10457" "/opt/rustwide/cargo-home/bin/cargo" "+ce59db7a1b1b012fb2793c4641c1bdecad7a128b" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] 00c6dd1e444abfa76b71ee83fc4aac8894cf27834f393c843c77f7b8ebdfe386
[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" "00c6dd1e444abfa76b71ee83fc4aac8894cf27834f393c843c77f7b8ebdfe386", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "00c6dd1e444abfa76b71ee83fc4aac8894cf27834f393c843c77f7b8ebdfe386", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "00c6dd1e444abfa76b71ee83fc4aac8894cf27834f393c843c77f7b8ebdfe386", kill_on_drop: false }`
[INFO] [stdout] 00c6dd1e444abfa76b71ee83fc4aac8894cf27834f393c843c77f7b8ebdfe386
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-0/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-0/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" "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@sha256:20528e8c29e4536546f0102ce88568b16ea7538393a33fcca951030f7af10457" "/opt/rustwide/cargo-home/bin/cargo" "+ce59db7a1b1b012fb2793c4641c1bdecad7a128b" "build" "--frozen" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] 4e38fbbaf6527a2b58c52998f099349f35fc145b62110e66b37e921fb801a5d9
[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" "4e38fbbaf6527a2b58c52998f099349f35fc145b62110e66b37e921fb801a5d9", kill_on_drop: false }`
[INFO] [stderr]    Compiling libc v0.2.43
[INFO] [stderr]    Compiling cfg-if v0.1.6
[INFO] [stderr]    Compiling futures v0.1.25
[INFO] [stderr]    Compiling scopeguard v0.3.3
[INFO] [stderr]    Compiling lazy_static v1.2.0
[INFO] [stderr]    Compiling stable_deref_trait v1.1.1
[INFO] [stderr]    Compiling nodrop v0.1.12
[INFO] [stderr]    Compiling memoffset v0.2.1
[INFO] [stderr]    Compiling smallvec v0.6.5
[INFO] [stderr]    Compiling parking_lot_core v0.3.1
[INFO] [stderr]    Compiling log v0.4.6
[INFO] [stderr]    Compiling arrayvec v0.4.7
[INFO] [stderr]    Compiling owning_ref v0.3.3
[INFO] [stderr]    Compiling lock_api v0.1.4
[INFO] [stderr]    Compiling iovec v0.1.2
[INFO] [stderr]    Compiling rand v0.5.5
[INFO] [stderr]    Compiling net2 v0.2.33
[INFO] [stderr]    Compiling num_cpus v1.8.0
[INFO] [stderr]    Compiling crossbeam-epoch v0.5.2
[INFO] [stderr]    Compiling bytes v0.4.10
[INFO] [stderr]    Compiling mio v0.6.16
[INFO] [stderr]    Compiling crossbeam-deque v0.6.1
[INFO] [stderr]    Compiling tokio-executor v0.1.5
[INFO] [stderr]    Compiling tokio-io v0.1.10
[INFO] [stderr]    Compiling mio-uds v0.6.7
[INFO] [stderr]    Compiling tokio-threadpool v0.1.8
[INFO] [stderr]    Compiling tokio-current-thread v0.1.3
[INFO] [stderr]    Compiling tokio-timer v0.2.7
[INFO] [stderr]    Compiling tokio-codec v0.1.1
[INFO] [stderr]    Compiling parking_lot v0.6.4
[INFO] [stderr]    Compiling tokio-reactor v0.1.6
[INFO] [stderr]    Compiling tokio-fs v0.1.4
[INFO] [stderr]    Compiling tokio-udp v0.1.2
[INFO] [stderr]    Compiling tokio-tcp v0.1.2
[INFO] [stderr]    Compiling tokio-uds v0.2.3
[INFO] [stderr]    Compiling tokio v0.1.11
[INFO] [stderr]    Compiling learn-tokio0 v0.1.0 (/opt/rustwide/workdir)
[INFO] [stdout] warning: unused import: `tokio::io`
[INFO] [stdout]  --> src/tcp_server.rs:5:5
[INFO] [stdout]   |
[INFO] [stdout] 5 | use tokio::io;
[INFO] [stdout]   |     ^^^^^^^^^
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(unused_imports)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused import: `tokio::prelude`
[INFO] [stdout]  --> src/tcp_server.rs:7:5
[INFO] [stdout]   |
[INFO] [stdout] 7 | use tokio::prelude::*;
[INFO] [stdout]   |     ^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `e`
[INFO] [stdout]   --> src/tcp_server.rs:37:31
[INFO] [stdout]    |
[INFO] [stdout] 37 |                     .map_err(|e| std::io::Error::new(std::io::ErrorKind::Other, "oh no!"))
[INFO] [stdout]    |                               ^ help: if this is intentional, prefix it with an underscore: `_e`
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(unused_variables)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused import: `futures::try_ready`
[INFO] [stdout]  --> src/concurrent_send_recv2.rs:7:5
[INFO] [stdout]   |
[INFO] [stdout] 7 | use futures::try_ready;
[INFO] [stdout]   |     ^^^^^^^^^^^^^^^^^^
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(unused_imports)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused import: `futures::try_ready`
[INFO] [stdout]  --> src/concurrent_send_recv.rs:7:5
[INFO] [stdout]   |
[INFO] [stdout] 7 | use futures::try_ready;
[INFO] [stdout]   |     ^^^^^^^^^^^^^^^^^^
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(unused_imports)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `e`
[INFO] [stdout]   --> src/tcp_server3.rs:29:31
[INFO] [stdout]    |
[INFO] [stdout] 29 |                     .map_err(|e| std::io::Error::new(std::io::ErrorKind::Other, "oh no!"))
[INFO] [stdout]    |                               ^ help: if this is intentional, prefix it with an underscore: `_e`
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(unused_variables)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `stdout`
[INFO] [stdout]   --> src/tcp_client.rs:12:13
[INFO] [stdout]    |
[INFO] [stdout] 12 |     let mut stdout = io::stdout();
[INFO] [stdout]    |             ^^^^^^ help: if this is intentional, prefix it with an underscore: `_stdout`
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(unused_variables)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: variable does not need to be mutable
[INFO] [stdout]   --> src/tcp_client.rs:12:9
[INFO] [stdout]    |
[INFO] [stdout] 12 |     let mut stdout = io::stdout();
[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] [stderr] error: could not compile `learn-tokio0`
[INFO] [stderr] 
[INFO] [stderr] Caused by:
[INFO] [stderr]   process didn't exit successfully: `rustc --crate-name tcp_server --edition=2018 src/tcp_server.rs --error-format=json --json=diagnostic-rendered-ansi --crate-type bin --emit=dep-info,link -C embed-bitcode=no -C debuginfo=2 -C metadata=20993cb037a5a822 -C extra-filename=-20993cb037a5a822 --out-dir /opt/rustwide/target/debug/deps -L dependency=/opt/rustwide/target/debug/deps --extern bytes=/opt/rustwide/target/debug/deps/libbytes-87a05e5b42d52cb4.rlib --extern futures=/opt/rustwide/target/debug/deps/libfutures-a6499817d78b9966.rlib --extern tokio=/opt/rustwide/target/debug/deps/libtokio-08a920368724e160.rlib --extern tokio_codec=/opt/rustwide/target/debug/deps/libtokio_codec-92976f2b3cb1b981.rlib --cap-lints=forbid` (signal: 9, SIGKILL: kill)
[INFO] [stderr] warning: build failed, waiting for other jobs to finish...
[INFO] [stdout] warning: 1 warning emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 1 warning emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 2 warnings emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr] error: build failed
[INFO] running `Command { std: "docker" "inspect" "4e38fbbaf6527a2b58c52998f099349f35fc145b62110e66b37e921fb801a5d9", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "4e38fbbaf6527a2b58c52998f099349f35fc145b62110e66b37e921fb801a5d9", kill_on_drop: false }`
[INFO] [stdout] 4e38fbbaf6527a2b58c52998f099349f35fc145b62110e66b37e921fb801a5d9