[INFO] fetching crate xain-fl 0.8.0...
[INFO] testing xain-fl-0.8.0 against 1.55.0 for beta-1.56-1
[INFO] extracting crate xain-fl 0.8.0 into /workspace/builds/worker-4/source
[INFO] validating manifest of crates.io crate xain-fl 0.8.0 on toolchain 1.55.0
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+1.55.0" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }`
[INFO] removed /workspace/builds/worker-4/source/rust-toolchain
[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-4/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" "+1.55.0" "fetch" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] [stderr]     Blocking waiting for file lock on package cache
[INFO] running `Command { std: "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" "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" "ghcr.io/rust-lang/crates-build-env/linux@sha256:a89201d6b5b9fd45c15d5952ece0a0129e7e80cb26ec023fd59cf09bc26f1604" "/opt/rustwide/cargo-home/bin/cargo" "+1.55.0" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] b9d1f2658beef6fccd0abb417c2770d1f997bc5cdc94b8d62edd57887cf285d9
[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" "b9d1f2658beef6fccd0abb417c2770d1f997bc5cdc94b8d62edd57887cf285d9", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "b9d1f2658beef6fccd0abb417c2770d1f997bc5cdc94b8d62edd57887cf285d9", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "b9d1f2658beef6fccd0abb417c2770d1f997bc5cdc94b8d62edd57887cf285d9", kill_on_drop: false }`
[INFO] [stdout] b9d1f2658beef6fccd0abb417c2770d1f997bc5cdc94b8d62edd57887cf285d9
[INFO] running `Command { std: "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" "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" "--user" "0:0" "--network" "none" "ghcr.io/rust-lang/crates-build-env/linux@sha256:a89201d6b5b9fd45c15d5952ece0a0129e7e80cb26ec023fd59cf09bc26f1604" "/opt/rustwide/cargo-home/bin/cargo" "+1.55.0" "build" "--frozen" "--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] 122aecac1c090dd1ad65066ce44cb1ec2b75e37fe1b0127b4241fddb48ddc16b
[INFO] running `Command { std: "docker" "start" "-a" "122aecac1c090dd1ad65066ce44cb1ec2b75e37fe1b0127b4241fddb48ddc16b", kill_on_drop: false }`
[INFO] [stderr]    Compiling syn v1.0.17
[INFO] [stderr]    Compiling libc v0.2.68
[INFO] [stderr]    Compiling serde v1.0.105
[INFO] [stderr]    Compiling proc-macro-hack v0.5.14
[INFO] [stderr]    Compiling ryu v1.0.3
[INFO] [stderr]    Compiling bytes v0.5.4
[INFO] [stderr]    Compiling proc-macro-nested v0.1.4
[INFO] [stderr]    Compiling siphasher v0.2.3
[INFO] [stderr]    Compiling byteorder v1.3.4
[INFO] [stderr]    Compiling arc-swap v0.4.5
[INFO] [stderr]    Compiling futures-io v0.3.4
[INFO] [stderr]    Compiling typenum v1.11.2
[INFO] [stderr]    Compiling regex-syntax v0.6.17
[INFO] [stderr]    Compiling unindent v0.1.5
[INFO] [stderr]    Compiling base64 v0.12.0
[INFO] [stderr]    Compiling anyhow v1.0.27
[INFO] [stderr]    Compiling unicode-width v0.1.7
[INFO] [stderr]    Compiling urlencoding v1.0.0
[INFO] [stderr]    Compiling raii-counter v0.2.1
[INFO] [stderr]    Compiling num-traits v0.2.11
[INFO] [stderr]    Compiling indexmap v1.3.2
[INFO] [stderr]    Compiling tracing-core v0.1.10
[INFO] [stderr]    Compiling nom v5.1.1
[INFO] [stderr]    Compiling sharded-slab v0.0.8
[INFO] [stderr]    Compiling unicode-normalization v0.1.12
[INFO] [stderr]    Compiling lock_api v0.3.3
[INFO] [stderr]    Compiling textwrap v0.11.0
[INFO] [stdout] error[E0557]: feature has been removed
[INFO] [stdout]   --> /opt/rustwide/cargo-home/registry/src/github.com-1ecc6299db9ec823/lock_api-0.3.3/src/lib.rs:89:42
[INFO] [stdout]    |
[INFO] [stdout] 89 | #![cfg_attr(feature = "nightly", feature(const_fn))]
[INFO] [stdout]    |                                          ^^^^^^^^ feature has been removed
[INFO] [stdout]    |
[INFO] [stdout]    = note: split into finer-grained feature gates
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]    Compiling http v0.2.0
[INFO] [stdout] error[E0554]: `#![feature]` may not be used on the stable 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] [stdout] error: aborting due to 2 previous errors
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] Some errors have detailed explanations: E0554, E0557.
[INFO] [stdout] 
[INFO] [stdout] For more information about an error, try `rustc --explain E0554`.
[INFO] [stdout] 
[INFO] [stderr] error: could not compile `lock_api` due to 3 previous errors
[INFO] [stderr] warning: build failed, waiting for other jobs to finish...
[INFO] [stderr] error: build failed
[INFO] running `Command { std: "docker" "inspect" "122aecac1c090dd1ad65066ce44cb1ec2b75e37fe1b0127b4241fddb48ddc16b", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "122aecac1c090dd1ad65066ce44cb1ec2b75e37fe1b0127b4241fddb48ddc16b", kill_on_drop: false }`
[INFO] [stdout] 122aecac1c090dd1ad65066ce44cb1ec2b75e37fe1b0127b4241fddb48ddc16b