[INFO] fetching crate arrow-flight 1.0.1...
[INFO] testing arrow-flight-1.0.1 against 1.47.0 for beta-1.48-1
[INFO] extracting crate arrow-flight 1.0.1 into /workspace/builds/worker-1/source
[INFO] validating manifest of crates.io crate arrow-flight 1.0.1 on toolchain 1.47.0
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+1.47.0" "read-manifest" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] started tweaking crates.io crate arrow-flight 1.0.1
[INFO] finished tweaking crates.io crate arrow-flight 1.0.1
[INFO] tweaked toml for crates.io crate arrow-flight 1.0.1 written to /workspace/builds/worker-1/source/Cargo.toml
[INFO] crate crates.io crate arrow-flight 1.0.1 already has a lockfile, it will not be regenerated
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+1.47.0" "fetch" "--locked" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-1/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-1/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" "+1.47.0" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] 04b8cc59e9377c5fa9022a7594e3efdf12f345cff62bf4f5b05ec5b9e2b4dd19
[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" "04b8cc59e9377c5fa9022a7594e3efdf12f345cff62bf4f5b05ec5b9e2b4dd19", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "04b8cc59e9377c5fa9022a7594e3efdf12f345cff62bf4f5b05ec5b9e2b4dd19", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "04b8cc59e9377c5fa9022a7594e3efdf12f345cff62bf4f5b05ec5b9e2b4dd19", kill_on_drop: false }`
[INFO] [stdout] 04b8cc59e9377c5fa9022a7594e3efdf12f345cff62bf4f5b05ec5b9e2b4dd19
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-1/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-1/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" "rustops/crates-build-env@sha256:d92eaeed33fa75130ca1ee6c8a01d1ffb62bac859dfdfb3450e3e5d1c0146529" "/opt/rustwide/cargo-home/bin/cargo" "+1.47.0" "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] 234f9822a4b4d249b1bddbb48badd3a19dac5d233d06bbd24877a682276c53ba
[INFO] running `Command { std: "docker" "start" "-a" "234f9822a4b4d249b1bddbb48badd3a19dac5d233d06bbd24877a682276c53ba", kill_on_drop: false }`
[INFO] [stderr]    Compiling syn v1.0.38
[INFO] [stderr]    Compiling libc v0.2.76
[INFO] [stderr]    Compiling pin-project-internal v0.4.23
[INFO] [stderr]    Compiling futures-sink v0.3.5
[INFO] [stderr]    Compiling anyhow v1.0.32
[INFO] [stderr]    Compiling futures-task v0.3.5
[INFO] [stderr]    Compiling either v1.6.0
[INFO] [stderr]    Compiling tower-layer v0.3.0
[INFO] [stderr]    Compiling byteorder v1.3.4
[INFO] [stderr]    Compiling serde v1.0.115
[INFO] [stderr]    Compiling fixedbitset v0.2.0
[INFO] [stderr]    Compiling multimap v0.8.1
[INFO] [stderr]    Compiling serde_derive v1.0.115
[INFO] [stderr]    Compiling serde_json v1.0.57
[INFO] [stderr]    Compiling futures-io v0.3.5
[INFO] [stderr]    Compiling base64 v0.11.0
[INFO] [stderr]    Compiling hashbrown v0.8.2
[INFO] [stderr]    Compiling indexmap v1.5.1
[INFO] [stderr]    Compiling num-traits v0.2.12
[INFO] [stderr]    Compiling tracing-core v0.1.14
[INFO] [stderr]    Compiling num-integer v0.1.43
[INFO] [stderr]    Compiling num-bigint v0.3.0
[INFO] [stderr]    Compiling num-rational v0.3.0
[INFO] [stderr]    Compiling num-iter v0.1.41
[INFO] [stderr]    Compiling http v0.2.1
[INFO] [stderr]    Compiling flatbuffers v0.6.1
[INFO] [stderr]    Compiling futures-channel v0.3.5
[INFO] [stderr]    Compiling itertools v0.8.2
[INFO] [stderr]    Compiling csv-core v0.1.10
[INFO] [stderr]    Compiling regex v1.3.9
[INFO] [stderr]    Compiling regex-automata v0.1.9
[INFO] [stderr]    Compiling net2 v0.2.34
[INFO] [stderr]    Compiling iovec v0.1.4
[INFO] [stderr]    Compiling getrandom v0.1.14
[INFO] [stderr]    Compiling which v3.1.1
[INFO] [stderr]    Compiling time v0.1.43
[INFO] [stderr]    Compiling socket2 v0.3.12
[INFO] [stderr]    Compiling petgraph v0.5.1
[INFO] [stderr]    Compiling rand_core v0.5.1
[INFO] [stderr]    Compiling prost-build v0.6.1
[INFO] [stderr]    Compiling mio v0.6.22
[INFO] [stderr]    Compiling rand_chacha v0.2.2
[INFO] [stderr]    Compiling rand_pcg v0.2.1
[INFO] [stderr]    Compiling num-complex v0.3.0
[INFO] [stderr]    Compiling rand v0.7.3
[INFO] [stderr]    Compiling chrono v0.4.15
[INFO] [stderr]    Compiling http-body v0.3.1
[INFO] [stderr]    Compiling tempfile v3.1.0
[INFO] [stderr]    Compiling num v0.3.0
[INFO] [stderr]    Compiling bstr v0.2.13
[INFO] [stderr]    Compiling csv v1.1.3
[INFO] [stderr]    Compiling tokio-macros v0.2.5
[INFO] [stderr]    Compiling tracing-attributes v0.1.11
[INFO] [stderr]    Compiling prost-derive v0.6.1
[INFO] [stderr]    Compiling async-stream-impl v0.2.1
[INFO] [stderr]    Compiling async-trait v0.1.38
[INFO] [stderr]    Compiling tokio v0.2.22
[INFO] [stderr]    Compiling async-stream v0.2.1
[INFO] [stderr]    Compiling tracing v0.1.19
[INFO] [stderr]    Compiling prost v0.6.1
[INFO] [stderr]    Compiling prost-types v0.6.1
[INFO] [stderr]    Compiling pin-project v0.4.23
[INFO] [stderr]    Compiling futures-util v0.3.5
[INFO] [stderr]    Compiling tower-discover v0.3.0
[INFO] [stderr]    Compiling tower-load-shed v0.3.0
[INFO] [stderr]    Compiling tracing-futures v0.2.4
[INFO] [stderr]    Compiling arrow v1.0.1
[INFO] [stderr]    Compiling tower-load v0.3.0
[INFO] [stderr]    Compiling tokio-util v0.3.1
[INFO] [stderr]    Compiling tower-timeout v0.3.0
[INFO] [stderr]    Compiling tower-retry v0.3.0
[INFO] [stderr]    Compiling tower-make v0.3.0
[INFO] [stderr]    Compiling tower-buffer v0.3.0
[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/arrow-1.0.1/src/lib.rs:24:1
[INFO] [stdout]    |
[INFO] [stdout] 24 | #![feature(specialization)]
[INFO] [stdout]    | ^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]    Compiling tower-limit v0.3.1
[INFO] [stderr]    Compiling tonic-build v0.2.0
[INFO] [stderr]    Compiling h2 v0.2.6
[INFO] [stderr]    Compiling tower-ready-cache v0.3.1
[INFO] [stderr]    Compiling tower-util v0.3.1
[INFO] [stderr]    Compiling futures v0.3.5
[INFO] [stderr]    Compiling tower-balance v0.3.0
[INFO] [stderr]    Compiling tower v0.3.1
[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 `arrow`.
[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" "234f9822a4b4d249b1bddbb48badd3a19dac5d233d06bbd24877a682276c53ba", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "234f9822a4b4d249b1bddbb48badd3a19dac5d233d06bbd24877a682276c53ba", kill_on_drop: false }`
[INFO] [stdout] 234f9822a4b4d249b1bddbb48badd3a19dac5d233d06bbd24877a682276c53ba
