[INFO] fetching crate loader-rs 0.7.0...
[INFO] testing loader-rs-0.7.0 against 1.44.0 for beta-1.45-1
[INFO] extracting crate loader-rs 0.7.0 into /workspace/builds/worker-7/source
[INFO] validating manifest of crates.io crate loader-rs 0.7.0 on toolchain 1.44.0
[INFO] running `"/workspace/cargo-home/bin/cargo" "+1.44.0" "read-manifest" "--manifest-path" "Cargo.toml"`
[INFO] started tweaking crates.io crate loader-rs 0.7.0
[INFO] finished tweaking crates.io crate loader-rs 0.7.0
[INFO] tweaked toml for crates.io crate loader-rs 0.7.0 written to /workspace/builds/worker-7/source/Cargo.toml
[INFO] running `"/workspace/cargo-home/bin/cargo" "+1.44.0" "generate-lockfile" "--manifest-path" "Cargo.toml" "-Zno-index-update"`
[INFO] running `"/workspace/cargo-home/bin/cargo" "+1.44.0" "fetch" "--locked" "--manifest-path" "Cargo.toml"`
[INFO] [stderr]     Blocking waiting for file lock on package cache
[INFO] running `"docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-7/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-7/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] d9a14ad3106b27ca96f864eb36e7790235560a5986e63d034962ba9fd545334e
[INFO] running `"docker" "start" "-a" "d9a14ad3106b27ca96f864eb36e7790235560a5986e63d034962ba9fd545334e"`
[INFO] [stderr] sudo: setrlimit(RLIMIT_CORE): Operation not permitted
[INFO] [stderr]    Compiling scoped-tls-hkt v0.1.2
[INFO] [stderr]    Compiling async-task v3.0.0
[INFO] [stderr]    Compiling strum v0.18.0
[INFO] [stderr]    Compiling futures-task v0.3.5
[INFO] [stderr]    Compiling log v0.4.8
[INFO] [stderr]    Compiling socket2 v0.3.12
[INFO] [stderr]    Compiling syn v1.0.30
[INFO] [stderr]    Compiling serde_urlencoded v0.6.1
[INFO] [stderr]    Compiling async-compression v0.3.4
[INFO] [stderr]    Compiling mio v0.6.22
[INFO] [stderr]    Compiling want v0.3.0
[INFO] [stderr]    Compiling kv-log-macro v1.0.6
[INFO] [stderr]    Compiling native-tls v0.2.4
[INFO] [stderr]    Compiling tokio v0.2.21
[INFO] [stderr]    Compiling tokio-util v0.3.1
[INFO] [stderr]    Compiling tokio-tls v0.3.1
[INFO] [stderr]    Compiling darling_core v0.10.2
[INFO] [stderr]    Compiling pin-project-internal v0.4.19
[INFO] [stderr]    Compiling async-attributes v1.1.1
[INFO] [stderr]    Compiling strum_macros v0.18.0
[INFO] [stderr]    Compiling darling_macro v0.10.2
[INFO] [stderr]    Compiling darling v0.10.2
[INFO] [stderr]    Compiling pin-project v0.4.19
[INFO] [stderr]    Compiling futures-util v0.3.5
[INFO] [stderr]    Compiling piper v0.1.3
[INFO] [stderr]    Compiling h2 v0.2.5
[INFO] [stderr]    Compiling smol v0.1.11
[INFO] [stderr]    Compiling async-std v1.6.0
[INFO] [stderr]    Compiling hyper v0.13.6
[INFO] [stderr]    Compiling hyper-tls v0.4.1
[INFO] [stderr]    Compiling reqwest v0.10.6
[INFO] [stderr]    Compiling cached_proc_macro v0.1.1
[INFO] [stderr]    Compiling cached v0.13.1
[INFO] [stderr]    Compiling loader-rs v0.7.0 (/opt/rustwide/workdir)
[INFO] [stderr] error[E0554]: `#![feature]` may not be used on the stable release channel
[INFO] [stderr]   --> src/lib.rs:43:1
[INFO] [stderr]    |
[INFO] [stderr] 43 | #![feature(specialization)]
[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 `loader-rs`.
[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" "d9a14ad3106b27ca96f864eb36e7790235560a5986e63d034962ba9fd545334e"`
[INFO] running `"docker" "rm" "-f" "d9a14ad3106b27ca96f864eb36e7790235560a5986e63d034962ba9fd545334e"`
[INFO] [stdout] d9a14ad3106b27ca96f864eb36e7790235560a5986e63d034962ba9fd545334e