[INFO] updating cached repository https://github.com/chankyin/fstree
[INFO] running `"git" "-c" "credential.helper=" "-c" "credential.helper=/workspace/cargo-home/bin/git-credential-null" "-c" "remote.origin.fetch=refs/heads/*:refs/heads/*" "fetch" "origin" "--force" "--prune"`
[INFO] running `"git" "rev-parse" "HEAD"`
[INFO] [stdout] 11576f11f6258048a449ad2cebaf35ca8f2d79c6
[INFO] testing chankyin/fstree against beta-2020-06-03 for beta-1.45-1
[INFO] running `"git" "clone" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fchankyin%2Ffstree" "/workspace/builds/worker-4/source"`
[INFO] [stderr] Cloning into '/workspace/builds/worker-4/source'...
[INFO] [stderr] done.
[INFO] validating manifest of git repo https://github.com/chankyin/fstree 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 git repo https://github.com/chankyin/fstree
[INFO] finished tweaking git repo https://github.com/chankyin/fstree
[INFO] tweaked toml for git repo https://github.com/chankyin/fstree written to /workspace/builds/worker-4/source/Cargo.toml
[INFO] crate git repo https://github.com/chankyin/fstree already has a lockfile, it will not be regenerated
[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-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" "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] 4e2e0ab70170f68d54f3b92fdb1cd48f36d0fc382ea8e1dd71fbd506cfba9e0c
[INFO] running `"docker" "start" "-a" "4e2e0ab70170f68d54f3b92fdb1cd48f36d0fc382ea8e1dd71fbd506cfba9e0c"`
[INFO] [stderr] sudo: setrlimit(RLIMIT_CORE): Operation not permitted
[INFO] [stderr]    Compiling spin v0.5.2
[INFO] [stderr]    Compiling syn v1.0.5
[INFO] [stderr]    Compiling futures-core-preview v0.3.0-alpha.18
[INFO] [stderr]    Compiling getrandom v0.1.11
[INFO] [stderr]    Compiling regex-syntax v0.6.11
[INFO] [stderr]    Compiling serde v1.0.99
[INFO] [stderr]    Compiling filesize v0.1.0
[INFO] [stderr]    Compiling num-traits v0.2.8
[INFO] [stderr]    Compiling termios v0.3.1
[INFO] [stderr]    Compiling parking_lot_core v0.6.2
[INFO] [stderr]    Compiling bytes v0.4.12
[INFO] [stderr]    Compiling mio-uds v0.6.7
[INFO] [stderr]    Compiling futures-sink-preview v0.3.0-alpha.18
[INFO] [stderr]    Compiling futures-channel-preview v0.3.0-alpha.18
[INFO] [stderr]    Compiling lazy_static v1.4.0
[INFO] [stderr]    Compiling crossbeam-utils v0.6.6
[INFO] [stderr]    Compiling tracing-core v0.1.5
[INFO] [stderr]    Compiling c2-chacha v0.2.2
[INFO] [stderr]    Compiling thread_local v0.3.6
[INFO] [stderr]    Compiling clicolors-control v1.0.1
[INFO] [stderr]    Compiling futures-util-preview v0.3.0-alpha.18
[INFO] [stderr]    Compiling tokio-io v0.2.0-alpha.4
[INFO] [stderr]    Compiling parking_lot v0.9.0
[INFO] [stderr]    Compiling rand_core v0.5.1
[INFO] [stderr]    Compiling crossbeam-epoch v0.7.2
[INFO] [stderr]    Compiling crossbeam-queue v0.1.2
[INFO] [stderr]    Compiling crossbeam-channel v0.3.9
[INFO] [stderr]    Compiling tokio-codec v0.2.0-alpha.4
[INFO] [stderr]    Compiling crossbeam-deque v0.7.1
[INFO] [stderr]    Compiling rand_chacha v0.2.1
[INFO] [stderr]    Compiling rand v0.7.0
[INFO] [stderr]    Compiling number_prefix v0.2.8
[INFO] [stderr]    Compiling tempfile v3.1.0
[INFO] [stderr]    Compiling tokio-sync v0.2.0-alpha.4
[INFO] [stderr]    Compiling regex v1.2.1
[INFO] [stderr]    Compiling console v0.8.0
[INFO] [stderr]    Compiling indicatif v0.11.0
[INFO] [stderr]    Compiling dialoguer v0.4.0
[INFO] [stderr]    Compiling tracing-attributes v0.1.2
[INFO] [stderr]    Compiling serde_derive v1.0.99
[INFO] [stderr]    Compiling tokio-macros v0.2.0-alpha.4
[INFO] [stderr]    Compiling tracing v0.1.7
[INFO] [stderr]    Compiling tokio-executor v0.2.0-alpha.4
[INFO] [stderr]    Compiling tokio-fs v0.2.0-alpha.4
[INFO] [stderr]    Compiling tokio-timer v0.3.0-alpha.4
[INFO] [stderr]    Compiling tokio-net v0.2.0-alpha.4
[INFO] [stderr]    Compiling tokio v0.2.0-alpha.4
[INFO] [stderr]    Compiling fstree v0.1.0 (/opt/rustwide/workdir)
[INFO] [stderr] error[E0554]: `#![feature]` may not be used on the beta release channel
[INFO] [stderr]  --> src/main.rs:1:1
[INFO] [stderr]   |
[INFO] [stderr] 1 | #![feature(async_closure)]
[INFO] [stderr]   | ^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stderr] 
[INFO] [stderr] error: aborting due to previous error
[INFO] [stderr] 
[INFO] [stderr] For more information about this error, try `rustc --explain E0554`.
[INFO] [stderr] error: could not compile `fstree`.
[INFO] [stderr] 
[INFO] [stderr] To learn more, run the command again with --verbose.
[INFO] running `"docker" "inspect" "4e2e0ab70170f68d54f3b92fdb1cd48f36d0fc382ea8e1dd71fbd506cfba9e0c"`
[INFO] running `"docker" "rm" "-f" "4e2e0ab70170f68d54f3b92fdb1cd48f36d0fc382ea8e1dd71fbd506cfba9e0c"`
[INFO] [stdout] 4e2e0ab70170f68d54f3b92fdb1cd48f36d0fc382ea8e1dd71fbd506cfba9e0c