[INFO] fetching crate kudzu 0.1.0...
[INFO] testing kudzu-0.1.0 against 1.55.0 for beta-1.56-1
[INFO] extracting crate kudzu 0.1.0 into /workspace/builds/worker-2/source
[INFO] validating manifest of crates.io crate kudzu 0.1.0 on toolchain 1.55.0
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+1.55.0" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }`
[INFO] started tweaking crates.io crate kudzu 0.1.0
[INFO] finished tweaking crates.io crate kudzu 0.1.0
[INFO] tweaked toml for crates.io crate kudzu 0.1.0 written to /workspace/builds/worker-2/source/Cargo.toml
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+1.55.0" "generate-lockfile" "--manifest-path" "Cargo.toml" "-Zno-index-update", kill_on_drop: false }`
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+1.55.0" "fetch" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-2/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-2/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" "ghcr.io/rust-lang/crates-build-env/linux@sha256:a89201d6b5b9fd45c15d5952ece0a0129e7e80cb26ec023fd59cf09bc26f1604" "/opt/rustwide/cargo-home/bin/cargo" "+1.55.0" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] 9b67f5912caf0ed48033e9687490642a85e677f78f7bd6f445122ee178edb68e
[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" "9b67f5912caf0ed48033e9687490642a85e677f78f7bd6f445122ee178edb68e", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "9b67f5912caf0ed48033e9687490642a85e677f78f7bd6f445122ee178edb68e", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "9b67f5912caf0ed48033e9687490642a85e677f78f7bd6f445122ee178edb68e", kill_on_drop: false }`
[INFO] [stdout] 9b67f5912caf0ed48033e9687490642a85e677f78f7bd6f445122ee178edb68e
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-2/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-2/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" "ghcr.io/rust-lang/crates-build-env/linux@sha256:a89201d6b5b9fd45c15d5952ece0a0129e7e80cb26ec023fd59cf09bc26f1604" "/opt/rustwide/cargo-home/bin/cargo" "+1.55.0" "build" "--frozen" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] 9eace1c2eef5407657f88c7fa2b842f5d1a1fe4f1b57891f24b8c142e73aed8a
[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" "9eace1c2eef5407657f88c7fa2b842f5d1a1fe4f1b57891f24b8c142e73aed8a", kill_on_drop: false }`
[INFO] [stderr]    Compiling kudzu v0.1.0 (/opt/rustwide/workdir)
[INFO] [stdout] error[E0554]: `#![feature]` may not be used on the stable release channel
[INFO] [stdout]  --> src/lib.rs:1:1
[INFO] [stdout]   |
[INFO] [stdout] 1 | #![feature(manually_drop_take, atomic_min_max)]
[INFO] [stdout]   | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: use of deprecated associated function `std::sync::atomic::AtomicPtr::<T>::compare_and_swap`: Use `compare_exchange` or `compare_exchange_weak` instead
[INFO] [stdout]    --> src/skiplist/insert.rs:150:32
[INFO] [stdout]     |
[INFO] [stdout] 150 |             match succ == pred.compare_and_swap(succ, new_node_addr, AcqRel) {
[INFO] [stdout]     |                                ^^^^^^^^^^^^^^^^
[INFO] [stdout]     |
[INFO] [stdout]     = note: `#[warn(deprecated)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error: aborting due to previous error; 1 warning 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 `kudzu` due to 2 previous errors; 1 warning emitted
[INFO] running `Command { std: "docker" "inspect" "9eace1c2eef5407657f88c7fa2b842f5d1a1fe4f1b57891f24b8c142e73aed8a", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "9eace1c2eef5407657f88c7fa2b842f5d1a1fe4f1b57891f24b8c142e73aed8a", kill_on_drop: false }`
[INFO] [stdout] 9eace1c2eef5407657f88c7fa2b842f5d1a1fe4f1b57891f24b8c142e73aed8a