[INFO] fetching crate x11-input-mirror 0.3.6...
[INFO] testing x11-input-mirror-0.3.6 against beta-2021-01-01 for beta-1.50-1
[INFO] extracting crate x11-input-mirror 0.3.6 into /workspace/builds/worker-2/source
[INFO] validating manifest of crates.io crate x11-input-mirror 0.3.6 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 crates.io crate x11-input-mirror 0.3.6
[INFO] finished tweaking crates.io crate x11-input-mirror 0.3.6
[INFO] tweaked toml for crates.io crate x11-input-mirror 0.3.6 written to /workspace/builds/worker-2/source/Cargo.toml
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+beta-2021-01-01" "generate-lockfile" "--manifest-path" "Cargo.toml" "-Zno-index-update", kill_on_drop: false }`
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+beta-2021-01-01" "fetch" "--locked" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] [stderr]  Downloading crates ...
[INFO] [stderr]   Downloaded keystream v1.0.0
[INFO] [stderr]   Downloaded chacha v0.3.0
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-2/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-2/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:c8ac004eab7d63a0ad09a2dde3d3353ba464f767bee4de425dc8f74c46a1905e" "/opt/rustwide/cargo-home/bin/cargo" "+beta-2021-01-01" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stderr] WARNING: Your kernel does not support swap limit capabilities or the cgroup is not mounted. Memory limited without swap.
[INFO] [stdout] 37d44175a04ce3a22a389d95a7bc5bbcd6515c98e5c54c5197b9f4562212268c
[INFO] running `Command { std: "docker" "start" "-a" "37d44175a04ce3a22a389d95a7bc5bbcd6515c98e5c54c5197b9f4562212268c", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "37d44175a04ce3a22a389d95a7bc5bbcd6515c98e5c54c5197b9f4562212268c", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "37d44175a04ce3a22a389d95a7bc5bbcd6515c98e5c54c5197b9f4562212268c", kill_on_drop: false }`
[INFO] [stdout] 37d44175a04ce3a22a389d95a7bc5bbcd6515c98e5c54c5197b9f4562212268c
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-2/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-2/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:c8ac004eab7d63a0ad09a2dde3d3353ba464f767bee4de425dc8f74c46a1905e" "/opt/rustwide/cargo-home/bin/cargo" "+beta-2021-01-01" "build" "--frozen" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] 3820ef5c6df58e54d8a6b9b410ca89d774c89fd03896af0cb30384831a063bd4
[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" "3820ef5c6df58e54d8a6b9b410ca89d774c89fd03896af0cb30384831a063bd4", kill_on_drop: false }`
[INFO] [stderr]    Compiling typenum v1.12.0
[INFO] [stderr]    Compiling byteorder v1.3.4
[INFO] [stderr]    Compiling proc-macro2 v1.0.24
[INFO] [stderr]    Compiling serde v1.0.118
[INFO] [stderr]    Compiling byte-tools v0.3.1
[INFO] [stderr]    Compiling syn v1.0.57
[INFO] [stderr]    Compiling serde_derive v1.0.118
[INFO] [stderr]    Compiling rand_core v0.4.2
[INFO] [stderr]    Compiling keystream v1.0.0
[INFO] [stderr]    Compiling keccak v0.1.0
[INFO] [stderr]    Compiling opaque-debug v0.2.3
[INFO] [stderr]    Compiling block-padding v0.1.5
[INFO] [stderr]    Compiling rand_core v0.3.1
[INFO] [stderr]    Compiling rand v0.5.6
[INFO] [stderr]    Compiling chacha v0.3.0
[INFO] [stderr]    Compiling quote v1.0.8
[INFO] [stderr]    Compiling generic-array v0.12.3
[INFO] [stderr]    Compiling block-buffer v0.7.3
[INFO] [stderr]    Compiling digest v0.8.1
[INFO] [stderr]    Compiling sha3 v0.8.2
[INFO] [stderr]    Compiling toml v0.4.10
[INFO] [stderr]    Compiling x11-input-mirror v0.3.6 (/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(panic_info_message)]
[INFO] [stdout]   | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[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(int_to_from_bytes)]
[INFO] [stdout]   | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error: aborting due to 2 previous errors
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] For more information about this error, try `rustc --explain E0554`.
[INFO] [stdout] 
[INFO] [stderr] error: could not compile `x11-input-mirror`
[INFO] [stderr] 
[INFO] [stderr] To learn more, run the command again with --verbose.
[INFO] running `Command { std: "docker" "inspect" "3820ef5c6df58e54d8a6b9b410ca89d774c89fd03896af0cb30384831a063bd4", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "3820ef5c6df58e54d8a6b9b410ca89d774c89fd03896af0cb30384831a063bd4", kill_on_drop: false }`
[INFO] [stdout] 3820ef5c6df58e54d8a6b9b410ca89d774c89fd03896af0cb30384831a063bd4