[INFO] fetching crate tuifw-window 0.8.1...
[INFO] testing tuifw-window-0.8.1 against 1.49.0 for beta-1.50-1
[INFO] extracting crate tuifw-window 0.8.1 into /workspace/builds/worker-11/source
[INFO] validating manifest of crates.io crate tuifw-window 0.8.1 on toolchain 1.49.0
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+1.49.0" "read-manifest" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] started tweaking crates.io crate tuifw-window 0.8.1
[INFO] finished tweaking crates.io crate tuifw-window 0.8.1
[INFO] tweaked toml for crates.io crate tuifw-window 0.8.1 written to /workspace/builds/worker-11/source/Cargo.toml
[INFO] crate crates.io crate tuifw-window 0.8.1 already has a lockfile, it will not be regenerated
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+1.49.0" "fetch" "--locked" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-11/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-11/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" "+1.49.0" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] 212c8d29d8a5c0fbc9868eafbd2f1c3e245151ddacc9f6b638adcedd0e1f30b3
[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" "212c8d29d8a5c0fbc9868eafbd2f1c3e245151ddacc9f6b638adcedd0e1f30b3", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "212c8d29d8a5c0fbc9868eafbd2f1c3e245151ddacc9f6b638adcedd0e1f30b3", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "212c8d29d8a5c0fbc9868eafbd2f1c3e245151ddacc9f6b638adcedd0e1f30b3", kill_on_drop: false }`
[INFO] [stdout] 212c8d29d8a5c0fbc9868eafbd2f1c3e245151ddacc9f6b638adcedd0e1f30b3
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-11/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-11/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" "+1.49.0" "build" "--frozen" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] 70486b6be415a23e0f9f2685acd1703be8ae68bf052a8eb3f99c3a1cd2e9caf4
[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" "70486b6be415a23e0f9f2685acd1703be8ae68bf052a8eb3f99c3a1cd2e9caf4", kill_on_drop: false }`
[INFO] [stderr]    Compiling syn v1.0.42
[INFO] [stderr]    Compiling ppv-lite86 v0.2.9
[INFO] [stderr]    Compiling generics v0.2.5
[INFO] [stderr]    Compiling enum-derive-2018 v1.0.1
[INFO] [stderr]    Compiling paste v1.0.1
[INFO] [stderr]    Compiling macro-attr-2018 v1.1.0
[INFO] [stderr]    Compiling num-traits v0.2.12
[INFO] [stderr]    Compiling num-integer v0.1.43
[INFO] [stderr]    Compiling num-bigint v0.3.0
[INFO] [stderr]    Compiling proc-macro2 v1.0.23
[INFO] [stderr]    Compiling rand_pcg v0.2.1
[INFO] [stderr]    Compiling rand_chacha v0.2.2
[INFO] [stderr]    Compiling rand v0.7.3
[INFO] [stderr]    Compiling dyn-context v0.3.2
[INFO] [stderr]    Compiling quote v1.0.7
[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/dyn-context-0.3.2/src/lib.rs:1:32
[INFO] [stdout]   |
[INFO] [stdout] 1 | #![cfg_attr(feature="nightly", feature(never_type))]
[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 `dyn-context`
[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" "70486b6be415a23e0f9f2685acd1703be8ae68bf052a8eb3f99c3a1cd2e9caf4", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "70486b6be415a23e0f9f2685acd1703be8ae68bf052a8eb3f99c3a1cd2e9caf4", kill_on_drop: false }`
[INFO] [stdout] 70486b6be415a23e0f9f2685acd1703be8ae68bf052a8eb3f99c3a1cd2e9caf4