[INFO] fetching crate xain-fl 0.8.0...
[INFO] checking xain-fl-0.8.0 against beta for pr-78714
[INFO] extracting crate xain-fl 0.8.0 into /workspace/builds/worker-5/source
[INFO] validating manifest of crates.io crate xain-fl 0.8.0 on toolchain beta
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+beta" "read-manifest" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] started tweaking crates.io crate xain-fl 0.8.0
[INFO] finished tweaking crates.io crate xain-fl 0.8.0
[INFO] tweaked toml for crates.io crate xain-fl 0.8.0 written to /workspace/builds/worker-5/source/Cargo.toml
[INFO] crate crates.io crate xain-fl 0.8.0 already has a lockfile, it will not be regenerated
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+beta" "fetch" "--locked" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-5/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-5/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:d92eaeed33fa75130ca1ee6c8a01d1ffb62bac859dfdfb3450e3e5d1c0146529" "/opt/rustwide/cargo-home/bin/cargo" "+beta" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] b933d02caba2b91745f21487ee10b809ef5563c76aca5834cab6c44b5399ad5a
[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" "b933d02caba2b91745f21487ee10b809ef5563c76aca5834cab6c44b5399ad5a", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "b933d02caba2b91745f21487ee10b809ef5563c76aca5834cab6c44b5399ad5a", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "b933d02caba2b91745f21487ee10b809ef5563c76aca5834cab6c44b5399ad5a", kill_on_drop: false }`
[INFO] [stdout] b933d02caba2b91745f21487ee10b809ef5563c76aca5834cab6c44b5399ad5a
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-5/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-5/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=forbid" "-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:d92eaeed33fa75130ca1ee6c8a01d1ffb62bac859dfdfb3450e3e5d1c0146529" "/opt/rustwide/cargo-home/bin/cargo" "+beta" "check" "--frozen" "--all" "--all-targets" "--message-format=json", 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] ef7a70394bda757c8fb98635f9b145878a4112bbacfea7d875b02046b57241af
[INFO] running `Command { std: "docker" "start" "-a" "ef7a70394bda757c8fb98635f9b145878a4112bbacfea7d875b02046b57241af", kill_on_drop: false }`
[INFO] [stderr]     Blocking waiting for file lock on package cache
[INFO] [stderr]    Compiling proc-macro2 v1.0.9
[INFO] [stderr]    Compiling syn v1.0.17
[INFO] [stderr]    Compiling libc v0.2.68
[INFO] [stderr]    Compiling autocfg v0.1.7
[INFO] [stderr]    Compiling serde v1.0.105
[INFO] [stderr]    Compiling rand_core v0.4.2
[INFO] [stderr]    Compiling ryu v1.0.3
[INFO] [stderr]    Compiling version_check v0.1.5
[INFO] [stderr]    Compiling proc-macro-hack v0.5.14
[INFO] [stderr]     Checking bytes v0.5.4
[INFO] [stderr]     Checking futures-core v0.3.4
[INFO] [stderr]     Checking futures-sink v0.3.4
[INFO] [stderr]    Compiling siphasher v0.2.3
[INFO] [stderr]    Compiling byteorder v1.3.4
[INFO] [stderr]     Checking smallvec v1.2.0
[INFO] [stderr]    Compiling typenum v1.11.2
[INFO] [stderr]     Checking pin-utils v0.1.0-alpha.4
[INFO] [stderr]     Checking futures-task v0.3.4
[INFO] [stderr]     Checking futures-io v0.3.4
[INFO] [stderr]     Checking arc-swap v0.4.5
[INFO] [stderr]     Checking pin-project-lite v0.1.4
[INFO] [stderr]     Checking ppv-lite86 v0.2.6
[INFO] [stderr]    Compiling arrayvec v0.4.12
[INFO] [stderr]     Checking byte-tools v0.3.1
[INFO] [stderr]    Compiling itoa v0.4.5
[INFO] [stderr]     Checking nodrop v0.1.14
[INFO] [stderr]     Checking fake-simd v0.1.2
[INFO] [stderr]     Checking opaque-debug v0.2.3
[INFO] [stderr]     Checking remove_dir_all v0.5.2
[INFO] [stderr]     Checking static_assertions v0.3.4
[INFO] [stderr]    Compiling unindent v0.1.5
[INFO] [stderr]     Checking try-lock v0.2.2
[INFO] [stderr]     Checking tower-service v0.3.0
[INFO] [stderr]     Checking base64 v0.12.0
[INFO] [stderr]    Compiling anyhow v1.0.27
[INFO] [stderr]     Checking urlencoding v1.0.0
[INFO] [stderr]     Checking scoped-tls v1.0.0
[INFO] [stderr]     Checking raii-counter v0.2.1
[INFO] [stderr]     Checking predicates-core v1.0.0
[INFO] [stderr]     Checking treeline v0.1.0
[INFO] [stderr]     Checking normalize-line-endings v0.3.0
[INFO] [stderr]     Checking difference v2.0.0
[INFO] [stderr]     Checking downcast v0.10.0
[INFO] [stderr]     Checking fragile v0.3.0
[INFO] [stderr]    Compiling unicase v2.6.0
[INFO] [stderr]     Checking tracing-core v0.1.10
[INFO] [stderr]    Compiling nom v5.1.1
[INFO] [stderr]     Checking sharded-slab v0.0.8
[INFO] [stderr]     Checking futures-channel v0.3.4
[INFO] [stderr]    Compiling rand_core v0.3.1
[INFO] [stderr]    Compiling rand_jitter v0.1.4
[INFO] [stderr]     Checking unicode-normalization v0.1.12
[INFO] [stderr]     Checking block-padding v0.1.5
[INFO] [stderr]     Checking lock_api v0.3.3
[INFO] [stderr]    Compiling unicase v1.4.2
[INFO] [stderr]     Checking http v0.2.0
[INFO] [stderr]     Checking predicates-tree v1.0.0
[INFO] [stderr]    Compiling rand_chacha v0.1.1
[INFO] [stderr]    Compiling rand_pcg v0.1.2
[INFO] [stdout] error[E0554]: `#![feature]` may not be used on the beta release channel
[INFO] [stdout]   --> /opt/rustwide/cargo-home/registry/src/github.com-1ecc6299db9ec823/lock_api-0.3.3/src/lib.rs:89:34
[INFO] [stdout]    |
[INFO] [stdout] 89 | #![cfg_attr(feature = "nightly", feature(const_fn))]
[INFO] [stdout]    |                                  ^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]    Compiling rand v0.6.5
[INFO] [stderr]    Compiling rand_xorshift v0.1.1
[INFO] [stderr]    Compiling rand_hc v0.1.0
[INFO] [stderr]    Compiling rand_isaac v0.1.1
[INFO] [stdout] error: aborting due to previous error
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] For more information about this error, try `rustc --explain E0554`.
[INFO] [stdout] 
[INFO] [stderr] error: could not compile `lock_api`
[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 `Command { std: "docker" "inspect" "ef7a70394bda757c8fb98635f9b145878a4112bbacfea7d875b02046b57241af", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "ef7a70394bda757c8fb98635f9b145878a4112bbacfea7d875b02046b57241af", kill_on_drop: false }`
[INFO] [stdout] ef7a70394bda757c8fb98635f9b145878a4112bbacfea7d875b02046b57241af