[INFO] cloning repository https://github.com/Emerentius/drain_experiments
[INFO] running `Command { std: "git" "-c" "credential.helper=" "-c" "credential.helper=/workspace/cargo-home/bin/git-credential-null" "clone" "--bare" "https://github.com/Emerentius/drain_experiments" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2FEmerentius%2Fdrain_experiments", kill_on_drop: false }`
[INFO] [stderr] Cloning into bare repository '/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2FEmerentius%2Fdrain_experiments'...
[INFO] running `Command { std: "git" "rev-parse" "HEAD", kill_on_drop: false }`
[INFO] [stdout] 5d693978cc0ae5cbb701145ae3d12f15e8ac80e7
[INFO] testing Emerentius/drain_experiments against beta-2021-01-01 for beta-1.50-1
[INFO] running `Command { std: "git" "clone" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2FEmerentius%2Fdrain_experiments" "/workspace/builds/worker-4/source", kill_on_drop: false }`
[INFO] [stderr] Cloning into '/workspace/builds/worker-4/source'...
[INFO] [stderr] done.
[INFO] validating manifest of git repo https://github.com/Emerentius/drain_experiments on toolchain beta-2021-01-01
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+beta-2021-01-01" "read-manifest" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] started tweaking git repo https://github.com/Emerentius/drain_experiments
[INFO] finished tweaking git repo https://github.com/Emerentius/drain_experiments
[INFO] tweaked toml for git repo https://github.com/Emerentius/drain_experiments written to /workspace/builds/worker-4/source/Cargo.toml
[INFO] crate git repo https://github.com/Emerentius/drain_experiments already has a lockfile, it will not be regenerated
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+beta-2021-01-01" "fetch" "--locked" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-4/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-4/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" "rustops/crates-build-env@sha256:b8eeb62f26c39b23691079a6cb6de528d8e88b4d71a8f6b1d30f8ba7d9c16de9" "/opt/rustwide/cargo-home/bin/cargo" "+beta-2021-01-01" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] 32b2e515462ecb01d46433eae2220b3415f1b7636c8934854e30061217abf95a
[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" "32b2e515462ecb01d46433eae2220b3415f1b7636c8934854e30061217abf95a", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "32b2e515462ecb01d46433eae2220b3415f1b7636c8934854e30061217abf95a", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "32b2e515462ecb01d46433eae2220b3415f1b7636c8934854e30061217abf95a", kill_on_drop: false }`
[INFO] [stdout] 32b2e515462ecb01d46433eae2220b3415f1b7636c8934854e30061217abf95a
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-4/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-4/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" "rustops/crates-build-env@sha256:b8eeb62f26c39b23691079a6cb6de528d8e88b4d71a8f6b1d30f8ba7d9c16de9" "/opt/rustwide/cargo-home/bin/cargo" "+beta-2021-01-01" "build" "--frozen" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] 30f14499b10fbeca05e9d09847405fb30bab88020ede85f198fb70c1fa6f52b2
[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" "30f14499b10fbeca05e9d09847405fb30bab88020ede85f198fb70c1fa6f52b2", kill_on_drop: false }`
[INFO] [stderr]    Compiling try_drain 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:1:1
[INFO] [stdout]   |
[INFO] [stdout] 1 | #![feature(drain_filter)]
[INFO] [stdout]   | ^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused imports: `Exhausting`, `IteratorExt`
[INFO] [stdout]   --> src/lib.rs:11:18
[INFO] [stdout]    |
[INFO] [stdout] 11 | use exhausting::{Exhausting, IteratorExt};
[INFO] [stdout]    |                  ^^^^^^^^^^  ^^^^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(unused_imports)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused import: `StreamElement`
[INFO] [stdout]   --> src/lib.rs:14:44
[INFO] [stdout]    |
[INFO] [stdout] 14 | use drain_element_streaming::{StreamDrain, StreamElement};
[INFO] [stdout]    |                                            ^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused import: `CursorIter`
[INFO] [stdout]   --> src/lib.rs:17:22
[INFO] [stdout]    |
[INFO] [stdout] 17 | use cursor::{Cursor, CursorIter};
[INFO] [stdout]    |                      ^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr] error: could not compile `try_drain`
[INFO] [stdout] error: aborting due to previous error; 3 warnings emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr] 
[INFO] [stdout] For more information about this error, try `rustc --explain E0554`.
[INFO] [stdout] 
[INFO] [stderr] To learn more, run the command again with --verbose.
[INFO] running `Command { std: "docker" "inspect" "30f14499b10fbeca05e9d09847405fb30bab88020ede85f198fb70c1fa6f52b2", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "30f14499b10fbeca05e9d09847405fb30bab88020ede85f198fb70c1fa6f52b2", kill_on_drop: false }`
[INFO] [stdout] 30f14499b10fbeca05e9d09847405fb30bab88020ede85f198fb70c1fa6f52b2