[INFO] fetching crate biostats 0.6.3...
[INFO] testing biostats-0.6.3 against 1.54.0 for beta-1.55-1
[INFO] extracting crate biostats 0.6.3 into /workspace/builds/worker-20/source
[INFO] validating manifest of crates.io crate biostats 0.6.3 on toolchain 1.54.0
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+1.54.0" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }`
[INFO] removed /workspace/builds/worker-20/source/rust-toolchain
[INFO] started tweaking crates.io crate biostats 0.6.3
[INFO] finished tweaking crates.io crate biostats 0.6.3
[INFO] tweaked toml for crates.io crate biostats 0.6.3 written to /workspace/builds/worker-20/source/Cargo.toml
[INFO] crate crates.io crate biostats 0.6.3 already has a lockfile, it will not be regenerated
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+1.54.0" "fetch" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] [stderr]     Blocking waiting for file lock on package cache
[INFO] [stderr]  Downloading crates ...
[INFO] [stderr]   Downloaded ndarray-rand v0.9.0
[INFO] [stderr]   Downloaded libc v0.2.73
[INFO] [stderr]   Downloaded program-flow v0.1.3
[INFO] [stderr]   Downloaded biofile v1.10.2
[INFO] [stderr]   Downloaded math v0.10.0
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-20/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-20/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@sha256:34b6a614d2c27851fe6cbf88fbd1137609cefab8b10d0615aaeb6fd47975d74e" "/opt/rustwide/cargo-home/bin/cargo" "+1.54.0" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] 648ef957cf7eba039c844193a33bf52d15a19259691b097fc8175f1b7035c997
[INFO] running `Command { std: "docker" "start" "-a" "648ef957cf7eba039c844193a33bf52d15a19259691b097fc8175f1b7035c997", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "648ef957cf7eba039c844193a33bf52d15a19259691b097fc8175f1b7035c997", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "648ef957cf7eba039c844193a33bf52d15a19259691b097fc8175f1b7035c997", kill_on_drop: false }`
[INFO] [stdout] 648ef957cf7eba039c844193a33bf52d15a19259691b097fc8175f1b7035c997
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-20/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-20/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@sha256:34b6a614d2c27851fe6cbf88fbd1137609cefab8b10d0615aaeb6fd47975d74e" "/opt/rustwide/cargo-home/bin/cargo" "+1.54.0" "build" "--frozen" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] 0f5747670e0a0024c6d8b02c2c5e20dee3823f68217ae3abe6b204f10d943032
[INFO] running `Command { std: "docker" "start" "-a" "0f5747670e0a0024c6d8b02c2c5e20dee3823f68217ae3abe6b204f10d943032", kill_on_drop: false }`
[INFO] [stderr]    Compiling libc v0.2.73
[INFO] [stderr]    Compiling getrandom v0.1.14
[INFO] [stderr]    Compiling rayon-core v1.7.1
[INFO] [stderr]    Compiling either v1.5.3
[INFO] [stderr]    Compiling log v0.4.11
[INFO] [stderr]    Compiling matrixmultiply v0.1.15
[INFO] [stderr]    Compiling unicode-width v0.1.8
[INFO] [stderr]    Compiling ppv-lite86 v0.2.8
[INFO] [stderr]    Compiling rawpointer v0.1.0
[INFO] [stderr]    Compiling ndarray v0.12.1
[INFO] [stderr]    Compiling num-traits v0.2.12
[INFO] [stderr]    Compiling memoffset v0.5.5
[INFO] [stderr]    Compiling num-integer v0.1.43
[INFO] [stderr]    Compiling num-complex v0.2.4
[INFO] [stderr]    Compiling num-bigint v0.2.6
[INFO] [stderr]    Compiling num-iter v0.1.41
[INFO] [stderr]    Compiling num-rational v0.2.4
[INFO] [stderr]    Compiling rayon v1.3.1
[INFO] [stderr]    Compiling textwrap v0.11.0
[INFO] [stderr]    Compiling itertools v0.7.11
[INFO] [stderr]    Compiling crossbeam-epoch v0.8.2
[INFO] [stderr]    Compiling num_cpus v1.13.0
[INFO] [stderr]    Compiling atty v0.2.14
[INFO] [stderr]    Compiling crossbeam-deque v0.7.3
[INFO] [stderr]    Compiling clap v2.33.3
[INFO] [stderr]    Compiling rand_core v0.5.1
[INFO] [stderr]    Compiling rand_chacha v0.2.2
[INFO] [stderr]    Compiling rand v0.7.3
[INFO] [stderr]    Compiling num v0.2.1
[INFO] [stderr]    Compiling program-flow v0.1.3
[INFO] [stderr]    Compiling math v0.10.0
[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/math-0.10.0/src/lib.rs:3:1
[INFO] [stdout]   |
[INFO] [stdout] 3 | #![feature(drain_filter)]
[INFO] [stdout]   | ^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[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/math-0.10.0/src/lib.rs:4:1
[INFO] [stdout]   |
[INFO] [stdout] 4 | #![feature(bool_to_option)]
[INFO] [stdout]   | ^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error: aborting due to 2 previous errors
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] For more information about this error, try `rustc --explain E0554`.
[INFO] [stdout] 
[INFO] [stderr] error: could not compile `math`
[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" "0f5747670e0a0024c6d8b02c2c5e20dee3823f68217ae3abe6b204f10d943032", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "0f5747670e0a0024c6d8b02c2c5e20dee3823f68217ae3abe6b204f10d943032", kill_on_drop: false }`
[INFO] [stdout] 0f5747670e0a0024c6d8b02c2c5e20dee3823f68217ae3abe6b204f10d943032
