[INFO] fetching crate cargo-n64 0.1.2...
[INFO] testing cargo-n64-0.1.2 against 1.49.0 for beta-1.50-1
[INFO] extracting crate cargo-n64 0.1.2 into /workspace/builds/worker-13/source
[INFO] validating manifest of crates.io crate cargo-n64 0.1.2 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 cargo-n64 0.1.2
[INFO] finished tweaking crates.io crate cargo-n64 0.1.2
[INFO] tweaked toml for crates.io crate cargo-n64 0.1.2 written to /workspace/builds/worker-13/source/Cargo.toml
[INFO] crate crates.io crate cargo-n64 0.1.2 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-13/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-13/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] [stderr] WARNING: Your kernel does not support swap limit capabilities or the cgroup is not mounted. Memory limited without swap.
[INFO] [stdout] 5bc96d3cb7c4aecdd94aa6d456ba0cdf45561853f3b76c5b4399ff3892116690
[INFO] running `Command { std: "docker" "start" "-a" "5bc96d3cb7c4aecdd94aa6d456ba0cdf45561853f3b76c5b4399ff3892116690", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "5bc96d3cb7c4aecdd94aa6d456ba0cdf45561853f3b76c5b4399ff3892116690", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "5bc96d3cb7c4aecdd94aa6d456ba0cdf45561853f3b76c5b4399ff3892116690", kill_on_drop: false }`
[INFO] [stdout] 5bc96d3cb7c4aecdd94aa6d456ba0cdf45561853f3b76c5b4399ff3892116690
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-13/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-13/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] [stderr] WARNING: Your kernel does not support swap limit capabilities or the cgroup is not mounted. Memory limited without swap.
[INFO] [stdout] feb13a8c6b76e2625df4fd097791a2d75ff456d9cb01ef76c6fc8ff703e6d2b0
[INFO] running `Command { std: "docker" "start" "-a" "feb13a8c6b76e2625df4fd097791a2d75ff456d9cb01ef76c6fc8ff703e6d2b0", kill_on_drop: false }`
[INFO] [stderr]    Compiling syn v1.0.14
[INFO] [stderr]    Compiling cc v1.0.50
[INFO] [stderr]    Compiling failure_derive v0.1.6
[INFO] [stderr]    Compiling crc32fast v1.2.0
[INFO] [stderr]    Compiling either v1.5.3
[INFO] [stderr]    Compiling plain v0.2.3
[INFO] [stderr]    Compiling time v0.1.42
[INFO] [stderr]    Compiling atty v0.2.14
[INFO] [stderr]    Compiling colored v1.9.2
[INFO] [stderr]    Compiling itertools v0.8.2
[INFO] [stderr]    Compiling chrono v0.4.10
[INFO] [stderr]    Compiling backtrace-sys v0.1.32
[INFO] [stderr]    Compiling fatfs v0.3.3
[INFO] [stderr]    Compiling backtrace v0.3.44
[INFO] [stderr]    Compiling synstructure v0.12.3
[INFO] [stderr]    Compiling serde_derive v1.0.104
[INFO] [stderr]    Compiling scroll_derive v0.10.1
[INFO] [stderr]    Compiling scroll v0.10.1
[INFO] [stderr]    Compiling failure v0.1.6
[INFO] [stderr]    Compiling goblin v0.2.0
[INFO] [stderr]    Compiling serde v1.0.104
[INFO] [stderr]    Compiling serde_json v1.0.48
[INFO] [stderr]    Compiling cargo-n64 v0.1.2 (/opt/rustwide/workdir)
[INFO] [stdout] error[E0554]: `#![feature]` may not be used on the stable release channel
[INFO] [stdout]  --> src/lib.rs:2:1
[INFO] [stdout]   |
[INFO] [stdout] 2 | #![feature(crate_visibility_modifier)]
[INFO] [stdout]   | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error[E0554]: `#![feature]` may not be used on the stable release channel
[INFO] [stdout]  --> src/lib.rs:3:1
[INFO] [stdout]   |
[INFO] [stdout] 3 | #![feature(try_trait)]
[INFO] [stdout]   | ^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error[E0554]: `#![feature]` may not be used on the stable release channel
[INFO] [stdout]  --> src/lib.rs:4:1
[INFO] [stdout]   |
[INFO] [stdout] 4 | #![feature(wrapping_int_impl)]
[INFO] [stdout]   | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error: aborting due to 3 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 `cargo-n64`
[INFO] [stderr] 
[INFO] [stderr] To learn more, run the command again with --verbose.
[INFO] running `Command { std: "docker" "inspect" "feb13a8c6b76e2625df4fd097791a2d75ff456d9cb01ef76c6fc8ff703e6d2b0", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "feb13a8c6b76e2625df4fd097791a2d75ff456d9cb01ef76c6fc8ff703e6d2b0", kill_on_drop: false }`
[INFO] [stdout] feb13a8c6b76e2625df4fd097791a2d75ff456d9cb01ef76c6fc8ff703e6d2b0