[INFO] crate magic-ring-buffer 0.1.0 is already in cache
[INFO] testing magic-ring-buffer-0.1.0 against beta-2020-06-03 for beta-1.45-1
[INFO] extracting crate magic-ring-buffer 0.1.0 into /workspace/builds/worker-2/source
[INFO] validating manifest of crates.io crate magic-ring-buffer 0.1.0 on toolchain beta-2020-06-03
[INFO] running `"/workspace/cargo-home/bin/cargo" "+beta-2020-06-03" "read-manifest" "--manifest-path" "Cargo.toml"`
[INFO] started tweaking crates.io crate magic-ring-buffer 0.1.0
[INFO] finished tweaking crates.io crate magic-ring-buffer 0.1.0
[INFO] tweaked toml for crates.io crate magic-ring-buffer 0.1.0 written to /workspace/builds/worker-2/source/Cargo.toml
[INFO] running `"/workspace/cargo-home/bin/cargo" "+beta-2020-06-03" "generate-lockfile" "--manifest-path" "Cargo.toml" "-Zno-index-update"`
[INFO] running `"/workspace/cargo-home/bin/cargo" "+beta-2020-06-03" "fetch" "--locked" "--manifest-path" "Cargo.toml"`
[INFO] running `"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" "MAP_USER_ID=0" "-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" "--network" "none" "rustops/crates-build-env" "/opt/rustwide/cargo-home/bin/cargo" "+beta-2020-06-03" "build" "--frozen"`
[INFO] [stderr] WARNING: Your kernel does not support swap limit capabilities or the cgroup is not mounted. Memory limited without swap.
[INFO] [stdout] 8b963b2f903c0c37de35a4a0cc6fd5ac110dbc655bbb90dd8f4d6f85d9ea85e4
[INFO] running `"docker" "start" "-a" "8b963b2f903c0c37de35a4a0cc6fd5ac110dbc655bbb90dd8f4d6f85d9ea85e4"`
[INFO] [stderr] sudo: setrlimit(RLIMIT_CORE): Operation not permitted
[INFO] [stderr]    Compiling likely v0.1.0
[INFO] [stderr]    Compiling strum v0.13.0
[INFO] [stderr]    Compiling errno v0.2.5
[INFO] [stderr]    Compiling strum_macros v0.13.0
[INFO] [stderr]    Compiling file-descriptors v0.8.7
[INFO] [stderr] error[E0554]: `#![feature]` may not be used on the beta release channel
[INFO] [stderr]   --> /opt/rustwide/cargo-home/registry/src/github.com-1ecc6299db9ec823/file-descriptors-0.8.7/src/lib.rs:10:1
[INFO] [stderr]    |
[INFO] [stderr] 10 | #![feature(core_intrinsics)]
[INFO] [stderr]    | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stderr] 
[INFO] [stderr] error[E0554]: `#![feature]` may not be used on the beta release channel
[INFO] [stderr]   --> /opt/rustwide/cargo-home/registry/src/github.com-1ecc6299db9ec823/file-descriptors-0.8.7/src/lib.rs:11:1
[INFO] [stderr]    |
[INFO] [stderr] 11 | #![feature(read_initializer)]
[INFO] [stderr]    | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stderr] 
[INFO] [stderr] error[E0554]: `#![feature]` may not be used on the beta release channel
[INFO] [stderr]   --> /opt/rustwide/cargo-home/registry/src/github.com-1ecc6299db9ec823/file-descriptors-0.8.7/src/lib.rs:12:1
[INFO] [stderr]    |
[INFO] [stderr] 12 | #![feature(try_from)]
[INFO] [stderr]    | ^^^^^^^^^^^^^^^^^^^^^
[INFO] [stderr] 
[INFO] [stderr] error: aborting due to 3 previous errors
[INFO] [stderr] 
[INFO] [stderr] For more information about this error, try `rustc --explain E0554`.
[INFO] [stderr] error: could not compile `file-descriptors`.
[INFO] [stderr] 
[INFO] [stderr] To learn more, run the command again with --verbose.
[INFO] running `"docker" "inspect" "8b963b2f903c0c37de35a4a0cc6fd5ac110dbc655bbb90dd8f4d6f85d9ea85e4"`
[INFO] running `"docker" "rm" "-f" "8b963b2f903c0c37de35a4a0cc6fd5ac110dbc655bbb90dd8f4d6f85d9ea85e4"`
[INFO] [stdout] 8b963b2f903c0c37de35a4a0cc6fd5ac110dbc655bbb90dd8f4d6f85d9ea85e4