[INFO] fetching crate wavefront 0.2.2...
[INFO] testing wavefront-0.2.2 against 1.59.0 for beta-1.60-1
[INFO] extracting crate wavefront 0.2.2 into /workspace/builds/worker-4/source
[INFO] validating manifest of crates.io crate wavefront 0.2.2 on toolchain 1.59.0
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+1.59.0" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }`
[INFO] started tweaking crates.io crate wavefront 0.2.2
[INFO] finished tweaking crates.io crate wavefront 0.2.2
[INFO] tweaked toml for crates.io crate wavefront 0.2.2 written to /workspace/builds/worker-4/source/Cargo.toml
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+1.59.0" "generate-lockfile" "--manifest-path" "Cargo.toml" "-Zno-index-update", kill_on_drop: false }`
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+1.59.0" "fetch" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] [stderr]     Blocking waiting for file lock on package cache
[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" "ghcr.io/rust-lang/crates-build-env/linux@sha256:0cd99ca24d8e8c98e67c542213511d985b8778b5bdcbb160e038429496686047" "/opt/rustwide/cargo-home/bin/cargo" "+1.59.0" "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] 5f4fd6982ab5d80005ef5df4ed94d18326cc3334a0b87efb4501511a2afdfde1
[INFO] running `Command { std: "docker" "start" "-a" "5f4fd6982ab5d80005ef5df4ed94d18326cc3334a0b87efb4501511a2afdfde1", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "5f4fd6982ab5d80005ef5df4ed94d18326cc3334a0b87efb4501511a2afdfde1", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "5f4fd6982ab5d80005ef5df4ed94d18326cc3334a0b87efb4501511a2afdfde1", kill_on_drop: false }`
[INFO] [stdout] 5f4fd6982ab5d80005ef5df4ed94d18326cc3334a0b87efb4501511a2afdfde1
[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" "ghcr.io/rust-lang/crates-build-env/linux@sha256:0cd99ca24d8e8c98e67c542213511d985b8778b5bdcbb160e038429496686047" "/opt/rustwide/cargo-home/bin/cargo" "+1.59.0" "build" "--frozen" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] 47fd1975c0a8880e31a68899b5500beb6e91898ca1abc87aa645f1bb2a73c1b1
[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" "47fd1975c0a8880e31a68899b5500beb6e91898ca1abc87aa645f1bb2a73c1b1", kill_on_drop: false }`
[INFO] [stderr]    Compiling wavefront v0.2.2 (/opt/rustwide/workdir)
[INFO] [stdout] error[E0554]: `#![feature]` may not be used on the stable release channel
[INFO] [stdout]   --> src/lib.rs:19:12
[INFO] [stdout]    |
[INFO] [stdout] 19 | #![feature(iter_map_while)]
[INFO] [stdout]    |            ^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: the feature `iter_map_while` has been stable since 1.57.0 and no longer requires an attribute to enable
[INFO] [stdout]   --> src/lib.rs:19:12
[INFO] [stdout]    |
[INFO] [stdout] 19 | #![feature(iter_map_while)]
[INFO] [stdout]    |            ^^^^^^^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(stable_features)]` 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 `wavefront` due to 2 previous errors; 1 warning emitted
[INFO] running `Command { std: "docker" "inspect" "47fd1975c0a8880e31a68899b5500beb6e91898ca1abc87aa645f1bb2a73c1b1", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "47fd1975c0a8880e31a68899b5500beb6e91898ca1abc87aa645f1bb2a73c1b1", kill_on_drop: false }`
[INFO] [stdout] 47fd1975c0a8880e31a68899b5500beb6e91898ca1abc87aa645f1bb2a73c1b1