[INFO] updating cached repository https://github.com/emk/drop-async-examples
[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] 48d2b3609ae85fbba497b5134135ded3fbedbb32
[INFO] testing emk/drop-async-examples against 1.44.0 for beta-1.45-1
[INFO] running `"git" "clone" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Femk%2Fdrop-async-examples" "/workspace/builds/worker-2/source"`
[INFO] [stderr] Cloning into '/workspace/builds/worker-2/source'...
[INFO] [stderr] done.
[INFO] validating manifest of git repo https://github.com/emk/drop-async-examples on toolchain 1.44.0
[INFO] running `"/workspace/cargo-home/bin/cargo" "+1.44.0" "read-manifest" "--manifest-path" "Cargo.toml"`
[INFO] started tweaking git repo https://github.com/emk/drop-async-examples
[INFO] finished tweaking git repo https://github.com/emk/drop-async-examples
[INFO] tweaked toml for git repo https://github.com/emk/drop-async-examples written to /workspace/builds/worker-2/source/Cargo.toml
[INFO] crate git repo https://github.com/emk/drop-async-examples already has a lockfile, it will not be regenerated
[INFO] running `"/workspace/cargo-home/bin/cargo" "+1.44.0" "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" "+1.44.0" "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] d071cd5a7f7838da44527ddf4e6e088d0d6084b719a8d7f3157399b5616d76ce
[INFO] running `"docker" "start" "-a" "d071cd5a7f7838da44527ddf4e6e088d0d6084b719a8d7f3157399b5616d76ce"`
[INFO] [stderr] sudo: setrlimit(RLIMIT_CORE): Operation not permitted
[INFO] [stderr]    Compiling libc v0.2.50
[INFO] [stderr]    Compiling cfg-if v0.1.7
[INFO] [stderr]    Compiling autocfg v0.1.2
[INFO] [stderr]    Compiling futures v0.1.25
[INFO] [stderr]    Compiling byteorder v1.3.1
[INFO] [stderr]    Compiling semver-parser v0.7.0
[INFO] [stderr]    Compiling arrayvec v0.4.10
[INFO] [stderr]    Compiling lazycell v1.2.1
[INFO] [stderr]    Compiling smallvec v0.6.9
[INFO] [stderr]    Compiling proc-macro2 v0.4.27
[INFO] [stderr]    Compiling fnv v1.0.6
[INFO] [stderr]    Compiling cc v1.0.30
[INFO] [stderr]    Compiling failure_derive v0.1.5
[INFO] [stderr]    Compiling rustc-demangle v0.1.13
[INFO] [stderr]    Compiling rand_jitter v0.1.3
[INFO] [stderr]    Compiling owning_ref v0.4.0
[INFO] [stderr]    Compiling crossbeam-utils v0.6.5
[INFO] [stderr]    Compiling log v0.4.6
[INFO] [stderr] error[E0554]: `#![feature]` may not be used on the stable release channel
[INFO] [stderr]    --> /opt/rustwide/cargo-home/registry/src/github.com-1ecc6299db9ec823/futures-0.1.25/src/lib.rs:161:34
[INFO] [stderr]     |
[INFO] [stderr] 161 | #![cfg_attr(feature = "nightly", feature(pin))]
[INFO] [stderr]     |                                  ^^^^^^^^^^^^
[INFO] [stderr] 
[INFO] [stderr]    Compiling lock_api v0.1.5
[INFO] [stderr]    Compiling semver v0.9.0
[INFO] [stderr]    Compiling rand_pcg v0.1.2
[INFO] [stderr]    Compiling rand_chacha v0.1.1
[INFO] [stderr]    Compiling rand v0.6.5
[INFO] [stderr]    Compiling backtrace v0.3.14
[INFO] [stderr]    Compiling crossbeam-queue v0.1.2
[INFO] [stderr]    Compiling rustc_version v0.2.3
[INFO] [stderr]    Compiling iovec v0.1.2
[INFO] [stderr]    Compiling rand_os v0.1.3
[INFO] [stderr]    Compiling num_cpus v1.10.0
[INFO] [stderr]    Compiling net2 v0.2.33
[INFO] [stderr]    Compiling crossbeam-epoch v0.7.1
[INFO] [stderr]    Compiling bytes v0.4.12
[INFO] [stderr]    Compiling quote v0.6.11
[INFO] [stderr]    Compiling mio v0.6.16
[INFO] [stderr]    Compiling crossbeam-deque v0.7.1
[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 `futures`.
[INFO] [stderr] 
[INFO] [stderr] To learn more, run the command again with --verbose.
[INFO] [stderr] warning: build failed, waiting for other jobs to finish...
[INFO] [stderr] error: build failed
[INFO] running `"docker" "inspect" "d071cd5a7f7838da44527ddf4e6e088d0d6084b719a8d7f3157399b5616d76ce"`
[INFO] running `"docker" "rm" "-f" "d071cd5a7f7838da44527ddf4e6e088d0d6084b719a8d7f3157399b5616d76ce"`
[INFO] [stdout] d071cd5a7f7838da44527ddf4e6e088d0d6084b719a8d7f3157399b5616d76ce