[INFO] fetching crate uhyve 0.0.24...
[INFO] testing uhyve-0.0.24 against beta-2021-01-01 for beta-1.50-1
[INFO] extracting crate uhyve 0.0.24 into /workspace/builds/worker-7/source
[INFO] validating manifest of crates.io crate uhyve 0.0.24 on toolchain beta-2021-01-01
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+beta-2021-01-01" "read-manifest" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] started tweaking crates.io crate uhyve 0.0.24
[INFO] finished tweaking crates.io crate uhyve 0.0.24
[INFO] tweaked toml for crates.io crate uhyve 0.0.24 written to /workspace/builds/worker-7/source/Cargo.toml
[INFO] crate crates.io crate uhyve 0.0.24 already has a lockfile, it will not be regenerated
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+beta-2021-01-01" "fetch" "--locked" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] [stderr]  Downloading crates ...
[INFO] [stderr]   Downloaded strum v0.8.0
[INFO] [stderr]   Downloaded strum_macros v0.8.0
[INFO] [stderr]   Downloaded goblin v0.2.3
[INFO] [stderr]   Downloaded kvm-bindings v0.3.0
[INFO] [stderr]   Downloaded kvm-ioctls v0.5.0
[INFO] [stderr]   Downloaded aligned_alloc v0.1.3
[INFO] [stderr]   Downloaded mac_address v1.0.4
[INFO] [stderr]   Downloaded bit_field v0.10.1
[INFO] [stderr]   Downloaded virtio-bindings v0.1.0
[INFO] [stderr]   Downloaded vmm-sys-util v0.7.0
[INFO] [stderr]   Downloaded xhypervisor v0.0.12
[INFO] [stderr]   Downloaded nix v0.18.0
[INFO] [stderr]   Downloaded x86 v0.34.0
[INFO] [stderr]   Downloaded gdb-protocol v0.1.0
[INFO] [stderr]   Downloaded tun-tap v0.1.2
[INFO] [stderr]   Downloaded raw-cpuid v8.1.2
[INFO] [stderr]   Downloaded burst v0.0.2
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-7/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-7/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:b8eeb62f26c39b23691079a6cb6de528d8e88b4d71a8f6b1d30f8ba7d9c16de9" "/opt/rustwide/cargo-home/bin/cargo" "+beta-2021-01-01" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] 332a05fbdf0dc54d95e91c6b15427b00570b315bbffd4be528424105b246b0d5
[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" "332a05fbdf0dc54d95e91c6b15427b00570b315bbffd4be528424105b246b0d5", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "332a05fbdf0dc54d95e91c6b15427b00570b315bbffd4be528424105b246b0d5", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "332a05fbdf0dc54d95e91c6b15427b00570b315bbffd4be528424105b246b0d5", kill_on_drop: false }`
[INFO] [stdout] 332a05fbdf0dc54d95e91c6b15427b00570b315bbffd4be528424105b246b0d5
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-7/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-7/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:b8eeb62f26c39b23691079a6cb6de528d8e88b4d71a8f6b1d30f8ba7d9c16de9" "/opt/rustwide/cargo-home/bin/cargo" "+beta-2021-01-01" "build" "--frozen" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] f3dc8a124def6ed6f4e171cf8fd0cf1527f8336b81a98ea4951c4556efc804b9
[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" "f3dc8a124def6ed6f4e171cf8fd0cf1527f8336b81a98ea4951c4556efc804b9", kill_on_drop: false }`
[INFO] [stderr]    Compiling libc v0.2.81
[INFO] [stderr]    Compiling syn v1.0.54
[INFO] [stderr]    Compiling mac_address v1.0.4
[INFO] [stderr]    Compiling x86 v0.34.0
[INFO] [stderr]    Compiling bit_field v0.10.1
[INFO] [stderr]    Compiling burst v0.0.2
[INFO] [stderr]    Compiling strum v0.8.0
[INFO] [stderr]    Compiling virtio-bindings v0.1.0
[INFO] [stderr]    Compiling tun-tap v0.1.2
[INFO] [stderr]    Compiling raw-cpuid v8.1.2
[INFO] [stderr]    Compiling gdb-protocol v0.1.0
[INFO] [stderr]    Compiling strum_macros v0.8.0
[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/x86-0.34.0/src/lib.rs:3:1
[INFO] [stdout]   |
[INFO] [stdout] 3 | #![feature(llvm_asm, core_intrinsics)]
[INFO] [stdout]   | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]    Compiling atty v0.2.14
[INFO] [stderr]    Compiling vmm-sys-util v0.7.0
[INFO] [stderr]    Compiling nix v0.18.0
[INFO] [stderr]    Compiling memchr v1.0.2
[INFO] [stderr]    Compiling aligned_alloc v0.1.3
[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 `x86`
[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" "f3dc8a124def6ed6f4e171cf8fd0cf1527f8336b81a98ea4951c4556efc804b9", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "f3dc8a124def6ed6f4e171cf8fd0cf1527f8336b81a98ea4951c4556efc804b9", kill_on_drop: false }`
[INFO] [stdout] f3dc8a124def6ed6f4e171cf8fd0cf1527f8336b81a98ea4951c4556efc804b9