[INFO] fetching crate transducers 0.0.2...
[INFO] testing transducers-0.0.2 against 1.47.0 for beta-1.48-1
[INFO] extracting crate transducers 0.0.2 into /workspace/builds/worker-4/source
[INFO] validating manifest of crates.io crate transducers 0.0.2 on toolchain 1.47.0
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+1.47.0" "read-manifest" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] started tweaking crates.io crate transducers 0.0.2
[INFO] finished tweaking crates.io crate transducers 0.0.2
[INFO] tweaked toml for crates.io crate transducers 0.0.2 written to /workspace/builds/worker-4/source/Cargo.toml
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+1.47.0" "generate-lockfile" "--manifest-path" "Cargo.toml" "-Zno-index-update", kill_on_drop: false }`
[INFO] [stderr]     Blocking waiting for file lock on package cache
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+1.47.0" "fetch" "--locked" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-4/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-4/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" "+1.47.0" "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] 7a23b6dd30f73d81ae589c22cd28f2eb61a7a25984f4a7a8c3978f8b0f00738e
[INFO] running `Command { std: "docker" "start" "-a" "7a23b6dd30f73d81ae589c22cd28f2eb61a7a25984f4a7a8c3978f8b0f00738e", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "7a23b6dd30f73d81ae589c22cd28f2eb61a7a25984f4a7a8c3978f8b0f00738e", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "7a23b6dd30f73d81ae589c22cd28f2eb61a7a25984f4a7a8c3978f8b0f00738e", kill_on_drop: false }`
[INFO] [stdout] 7a23b6dd30f73d81ae589c22cd28f2eb61a7a25984f4a7a8c3978f8b0f00738e
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-4/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-4/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:d92eaeed33fa75130ca1ee6c8a01d1ffb62bac859dfdfb3450e3e5d1c0146529" "/opt/rustwide/cargo-home/bin/cargo" "+1.47.0" "build" "--frozen" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] 14e1c13140c55ef4b8b685ff6d1613748eeedb60cee2d1f91937d2d2af1d16ba
[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" "14e1c13140c55ef4b8b685ff6d1613748eeedb60cee2d1f91937d2d2af1d16ba", kill_on_drop: false }`
[INFO] [stderr]    Compiling transducers v0.0.2 (/opt/rustwide/workdir)
[INFO] [stdout] error[E0554]: `#![feature]` may not be used on the stable release channel
[INFO] [stdout]   --> src/lib.rs:41:1
[INFO] [stdout]    |
[INFO] [stdout] 41 | #![feature(fn_traits, unboxed_closures)]
[INFO] [stdout]    | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: trait objects without an explicit `dyn` are deprecated
[INFO] [stdout]   --> src/transform.rs:22:15
[INFO] [stdout]    |
[INFO] [stdout] 22 |     step: Box<Fn(R, T) -> R + 't>
[INFO] [stdout]    |               ^^^^^^^^^^^^^^^^^^ help: use `dyn`: `dyn Fn(R, T) -> R + 't`
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(bare_trait_objects)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: trait objects without an explicit `dyn` are deprecated
[INFO] [stdout]   --> src/transform.rs:63:15
[INFO] [stdout]    |
[INFO] [stdout] 63 |     step: Box<Fn(R, T) -> R + 't>,
[INFO] [stdout]    |               ^^^^^^^^^^^^^^^^^^ help: use `dyn`: `dyn Fn(R, T) -> R + 't`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: trait objects without an explicit `dyn` are deprecated
[INFO] [stdout]    --> src/transform.rs:116:15
[INFO] [stdout]     |
[INFO] [stdout] 116 |     step: Box<Fn(R, T) -> R + 't>,
[INFO] [stdout]     |               ^^^^^^^^^^^^^^^^^^ help: use `dyn`: `dyn Fn(R, T) -> R + 't`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error: aborting due to previous error; 3 warnings emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] For more information about this error, try `rustc --explain E0554`.
[INFO] [stdout] 
[INFO] [stderr] error: could not compile `transducers`.
[INFO] [stderr] 
[INFO] [stderr] To learn more, run the command again with --verbose.
[INFO] running `Command { std: "docker" "inspect" "14e1c13140c55ef4b8b685ff6d1613748eeedb60cee2d1f91937d2d2af1d16ba", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "14e1c13140c55ef4b8b685ff6d1613748eeedb60cee2d1f91937d2d2af1d16ba", kill_on_drop: false }`
[INFO] [stdout] 14e1c13140c55ef4b8b685ff6d1613748eeedb60cee2d1f91937d2d2af1d16ba
