[INFO] fetching crate xargo 0.3.22...
[INFO] checking xargo-0.3.22 against beta for pr-78714
[INFO] extracting crate xargo 0.3.22 into /workspace/builds/worker-6/source
[INFO] validating manifest of crates.io crate xargo 0.3.22 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 xargo 0.3.22
[INFO] finished tweaking crates.io crate xargo 0.3.22
[INFO] tweaked toml for crates.io crate xargo 0.3.22 written to /workspace/builds/worker-6/source/Cargo.toml
[INFO] crate crates.io crate xargo 0.3.22 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-6/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-6/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] c1271da0ec1d7afea5f638abd7ffedc932239f47f266917b5fa715b66ca81fde
[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" "c1271da0ec1d7afea5f638abd7ffedc932239f47f266917b5fa715b66ca81fde", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "c1271da0ec1d7afea5f638abd7ffedc932239f47f266917b5fa715b66ca81fde", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "c1271da0ec1d7afea5f638abd7ffedc932239f47f266917b5fa715b66ca81fde", kill_on_drop: false }`
[INFO] [stdout] c1271da0ec1d7afea5f638abd7ffedc932239f47f266917b5fa715b66ca81fde
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-6/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-6/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] [stdout] 554359ccfe1692a2337105a7addbf937766f2d43a8b8ecfb1ff2f20307d492e4
[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" "554359ccfe1692a2337105a7addbf937766f2d43a8b8ecfb1ff2f20307d492e4", kill_on_drop: false }`
[INFO] [stderr]    Compiling libc v0.2.74
[INFO] [stderr]    Compiling serde v1.0.114
[INFO] [stderr]     Checking gimli v0.22.0
[INFO] [stderr]    Compiling serde_json v1.0.57
[INFO] [stderr]     Checking semver-parser v0.7.0
[INFO] [stderr]     Checking object v0.20.0
[INFO] [stderr]    Compiling xargo v0.3.22 (/opt/rustwide/workdir)
[INFO] [stderr]     Checking smallvec v1.4.1
[INFO] [stderr]     Checking instant v0.1.6
[INFO] [stderr]     Checking miniz_oxide v0.4.0
[INFO] [stderr]    Compiling error-chain v0.12.2
[INFO] [stderr]     Checking semver v0.9.0
[INFO] [stderr]     Checking rustc_version v0.2.3
[INFO] [stderr]     Checking dirs-sys v0.3.5
[INFO] [stderr]     Checking rand v0.4.6
[INFO] [stderr]     Checking fs2 v0.4.3
[INFO] [stderr]     Checking parking_lot_core v0.8.0
[INFO] [stderr]     Checking dirs v3.0.1
[INFO] [stderr]     Checking parking_lot v0.11.0
[INFO] [stderr]     Checking tempdir v0.3.7
[INFO] [stderr]     Checking addr2line v0.13.0
[INFO] [stderr]     Checking backtrace v0.3.50
[INFO] [stderr]     Checking toml v0.5.6
[INFO] [stdout] error[E0554]: `#![feature]` may not be used on the beta release channel
[INFO] [stdout]  --> tests/smoke.rs:3:1
[INFO] [stdout]   |
[INFO] [stdout] 3 | #![feature(const_fn)]
[INFO] [stdout]   | ^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[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 `xargo`
[INFO] [stderr] 
[INFO] [stderr] To learn more, run the command again with --verbose.
[INFO] running `Command { std: "docker" "inspect" "554359ccfe1692a2337105a7addbf937766f2d43a8b8ecfb1ff2f20307d492e4", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "554359ccfe1692a2337105a7addbf937766f2d43a8b8ecfb1ff2f20307d492e4", kill_on_drop: false }`
[INFO] [stdout] 554359ccfe1692a2337105a7addbf937766f2d43a8b8ecfb1ff2f20307d492e4