[INFO] fetching crate dyn-context 0.3.2...
[INFO] testing dyn-context-0.3.2 against 1.49.0 for beta-1.50-1
[INFO] extracting crate dyn-context 0.3.2 into /workspace/builds/worker-7/source
[INFO] validating manifest of crates.io crate dyn-context 0.3.2 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 dyn-context 0.3.2
[INFO] finished tweaking crates.io crate dyn-context 0.3.2
[INFO] tweaked toml for crates.io crate dyn-context 0.3.2 written to /workspace/builds/worker-7/source/Cargo.toml
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+1.49.0" "generate-lockfile" "--manifest-path" "Cargo.toml" "-Zno-index-update", kill_on_drop: false }`
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+1.49.0" "fetch" "--locked" "--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 macro-attr-2018 v1.1.0
[INFO] [stderr]   Downloaded generics v0.2.6
[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:c8ac004eab7d63a0ad09a2dde3d3353ba464f767bee4de425dc8f74c46a1905e" "/opt/rustwide/cargo-home/bin/cargo" "+1.49.0" "metadata" "--no-deps" "--format-version=1", 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] 497a26d9e1a1e893e1748736e831036e4a60df12ffc7d01d01b8ecc9927c84ba
[INFO] running `Command { std: "docker" "start" "-a" "497a26d9e1a1e893e1748736e831036e4a60df12ffc7d01d01b8ecc9927c84ba", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "497a26d9e1a1e893e1748736e831036e4a60df12ffc7d01d01b8ecc9927c84ba", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "497a26d9e1a1e893e1748736e831036e4a60df12ffc7d01d01b8ecc9927c84ba", kill_on_drop: false }`
[INFO] [stdout] 497a26d9e1a1e893e1748736e831036e4a60df12ffc7d01d01b8ecc9927c84ba
[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:c8ac004eab7d63a0ad09a2dde3d3353ba464f767bee4de425dc8f74c46a1905e" "/opt/rustwide/cargo-home/bin/cargo" "+1.49.0" "build" "--frozen" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] c68b4b3fc0ab3e95f3808c8093df8abdcfc3e5aa38bd4909249dba20b3bcc659
[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" "c68b4b3fc0ab3e95f3808c8093df8abdcfc3e5aa38bd4909249dba20b3bcc659", kill_on_drop: false }`
[INFO] [stderr]    Compiling paste v1.0.4
[INFO] [stderr]    Compiling generics v0.2.6
[INFO] [stderr]    Compiling dyn-context v0.3.2 (/opt/rustwide/workdir)
[INFO] [stdout] error[E0554]: `#![feature]` may not be used on the stable release channel
[INFO] [stdout]  --> 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] running `Command { std: "docker" "inspect" "c68b4b3fc0ab3e95f3808c8093df8abdcfc3e5aa38bd4909249dba20b3bcc659", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "c68b4b3fc0ab3e95f3808c8093df8abdcfc3e5aa38bd4909249dba20b3bcc659", kill_on_drop: false }`
[INFO] [stdout] c68b4b3fc0ab3e95f3808c8093df8abdcfc3e5aa38bd4909249dba20b3bcc659