[INFO] fetching crate rxrust 0.9.1...
[INFO] testing rxrust-0.9.1 against 1.47.0 for beta-1.48-1
[INFO] extracting crate rxrust 0.9.1 into /workspace/builds/worker-13/source
[INFO] validating manifest of crates.io crate rxrust 0.9.1 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 rxrust 0.9.1
[INFO] finished tweaking crates.io crate rxrust 0.9.1
[INFO] tweaked toml for crates.io crate rxrust 0.9.1 written to /workspace/builds/worker-13/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] 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-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:d92eaeed33fa75130ca1ee6c8a01d1ffb62bac859dfdfb3450e3e5d1c0146529" "/opt/rustwide/cargo-home/bin/cargo" "+1.47.0" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] 8b4522f03d9e6439a14a1164379e40ffe441fc54c78711daec3d9b91c9f517c0
[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" "8b4522f03d9e6439a14a1164379e40ffe441fc54c78711daec3d9b91c9f517c0", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "8b4522f03d9e6439a14a1164379e40ffe441fc54c78711daec3d9b91c9f517c0", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "8b4522f03d9e6439a14a1164379e40ffe441fc54c78711daec3d9b91c9f517c0", kill_on_drop: false }`
[INFO] [stdout] 8b4522f03d9e6439a14a1164379e40ffe441fc54c78711daec3d9b91c9f517c0
[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:d92eaeed33fa75130ca1ee6c8a01d1ffb62bac859dfdfb3450e3e5d1c0146529" "/opt/rustwide/cargo-home/bin/cargo" "+1.47.0" "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] 6594b34a8201147a8524a2f0925bedef5477b15868ac4acfd213db390091cd68
[INFO] running `Command { std: "docker" "start" "-a" "6594b34a8201147a8524a2f0925bedef5477b15868ac4acfd213db390091cd68", kill_on_drop: false }`
[INFO] [stderr]    Compiling futures-executor v0.3.6
[INFO] [stderr]    Compiling futures v0.3.6
[INFO] [stderr]    Compiling rxrust v0.9.1 (/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(
[INFO] [stdout] 3  | |   external_doc,
[INFO] [stdout] 4  | |   min_specialization,
[INFO] [stdout] 5  | |   drain_filter,
[INFO] [stdout] ...  |
[INFO] [stdout] 9  | |   generic_associated_types
[INFO] [stdout] 10 | | )]
[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 `rxrust`.
[INFO] [stderr] 
[INFO] [stderr] To learn more, run the command again with --verbose.
[INFO] running `Command { std: "docker" "inspect" "6594b34a8201147a8524a2f0925bedef5477b15868ac4acfd213db390091cd68", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "6594b34a8201147a8524a2f0925bedef5477b15868ac4acfd213db390091cd68", kill_on_drop: false }`
[INFO] [stdout] 6594b34a8201147a8524a2f0925bedef5477b15868ac4acfd213db390091cd68
