[INFO] cloning repository https://github.com/zjhken/MioPractice
[INFO] running `Command { std: "git" "-c" "credential.helper=" "-c" "credential.helper=/workspace/cargo-home/bin/git-credential-null" "clone" "--bare" "https://github.com/zjhken/MioPractice" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fzjhken%2FMioPractice", kill_on_drop: false }`
[INFO] [stderr] Cloning into bare repository '/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fzjhken%2FMioPractice'...
[INFO] running `Command { std: "git" "rev-parse" "HEAD", kill_on_drop: false }`
[INFO] [stdout] b7e077633c9c64e7342ee2e473eea1a4421e8a49
[INFO] testing zjhken/MioPractice 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%2Fzjhken%2FMioPractice" "/workspace/builds/worker-93/source", kill_on_drop: false }`
[INFO] [stderr] Cloning into '/workspace/builds/worker-93/source'...
[INFO] [stderr] done.
[INFO] validating manifest of git repo https://github.com/zjhken/MioPractice 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/zjhken/MioPractice
[INFO] finished tweaking git repo https://github.com/zjhken/MioPractice
[INFO] tweaked toml for git repo https://github.com/zjhken/MioPractice written to /workspace/builds/worker-93/source/Cargo.toml
[INFO] crate git repo https://github.com/zjhken/MioPractice 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]     Blocking waiting for file lock on package cache
[INFO] [stderr]  Downloading crates ...
[INFO] [stderr]   Downloaded mio v0.6.14
[INFO] [stderr]   Downloaded net2 v0.2.32
[INFO] [stderr]   Downloaded simple_logger v0.5.0
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-93/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-93/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] 33842988aae60b9fafbe909cfc015e47159fa679bf133adcda0491232966ec03
[INFO] running `Command { std: "docker" "start" "-a" "33842988aae60b9fafbe909cfc015e47159fa679bf133adcda0491232966ec03", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "33842988aae60b9fafbe909cfc015e47159fa679bf133adcda0491232966ec03", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "33842988aae60b9fafbe909cfc015e47159fa679bf133adcda0491232966ec03", kill_on_drop: false }`
[INFO] [stdout] 33842988aae60b9fafbe909cfc015e47159fa679bf133adcda0491232966ec03
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-93/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-93/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] 087df4e452451158344619db1316f7eb43d540a454828960981e79c2da4b4297
[INFO] running `Command { std: "docker" "start" "-a" "087df4e452451158344619db1316f7eb43d540a454828960981e79c2da4b4297", kill_on_drop: false }`
[INFO] [stderr]    Compiling libc v0.2.42
[INFO] [stderr]    Compiling cfg-if v0.1.3
[INFO] [stderr]    Compiling slab v0.4.0
[INFO] [stderr]    Compiling lazycell v0.6.0
[INFO] [stderr]    Compiling log v0.4.4
[INFO] [stderr]    Compiling time v0.1.40
[INFO] [stderr]    Compiling net2 v0.2.32
[INFO] [stderr]    Compiling iovec v0.1.2
[INFO] [stderr]    Compiling simple_logger v0.5.0
[INFO] [stderr]    Compiling mio v0.6.14
[INFO] [stderr]    Compiling MioPractice v0.1.0 (/opt/rustwide/workdir)
[INFO] [stdout] error[E0554]: `#![feature]` may not be used on the beta release channel
[INFO] [stdout]  --> src/lib.rs:2:1
[INFO] [stdout]   |
[INFO] [stdout] 2 | #![feature(nll)]
[INFO] [stdout]   | ^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error: aborting due to previous error
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] For more information about this error, try `rustc --explain E0554`.
[INFO] [stdout] 
[INFO] [stderr] error: could not compile `MioPractice` due to 2 previous errors
[INFO] running `Command { std: "docker" "inspect" "087df4e452451158344619db1316f7eb43d540a454828960981e79c2da4b4297", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "087df4e452451158344619db1316f7eb43d540a454828960981e79c2da4b4297", kill_on_drop: false }`
[INFO] [stdout] 087df4e452451158344619db1316f7eb43d540a454828960981e79c2da4b4297
