[INFO] fetching crate mkfs-ext2 0.1.0...
[INFO] testing mkfs-ext2-0.1.0 against 1.76.0 for beta-1.77-1
[INFO] extracting crate mkfs-ext2 0.1.0 into /workspace/builds/worker-5-tc1/source
[INFO] validating manifest of crates.io crate mkfs-ext2 0.1.0 on toolchain 1.76.0
[INFO] running `Command { std: CARGO_HOME="/workspace/cargo-home" RUSTUP_HOME="/workspace/rustup-home" "/workspace/cargo-home/bin/cargo" "+1.76.0" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }`
[INFO] started tweaking crates.io crate mkfs-ext2 0.1.0
[INFO] finished tweaking crates.io crate mkfs-ext2 0.1.0
[INFO] tweaked toml for crates.io crate mkfs-ext2 0.1.0 written to /workspace/builds/worker-5-tc1/source/Cargo.toml
[INFO] running `Command { std: CARGO_HOME="/workspace/cargo-home" RUSTUP_HOME="/workspace/rustup-home" "/workspace/cargo-home/bin/cargo" "+1.76.0" "generate-lockfile" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] [stderr]     Updating crates.io index
[INFO] running `Command { std: CARGO_HOME="/workspace/cargo-home" RUSTUP_HOME="/workspace/rustup-home" "/workspace/cargo-home/bin/cargo" "+1.76.0" "fetch" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] [stderr]  Downloading crates ...
[INFO] [stderr]   Downloaded mkfs-filesystem v0.1.0
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-5-tc1/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-5-tc1/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@sha256:2788e3201cd34a07e3172128adcd8b3090168a8e3bcc40d7c032b9dda1df7d1c" "/opt/rustwide/cargo-home/bin/cargo" "+1.76.0" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] ed808f4212ca89d9e43a4bfce042fba8ea53b6fe18660cab7affe4f0ad8e2876
[INFO] running `Command { std: "docker" "start" "-a" "ed808f4212ca89d9e43a4bfce042fba8ea53b6fe18660cab7affe4f0ad8e2876", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "ed808f4212ca89d9e43a4bfce042fba8ea53b6fe18660cab7affe4f0ad8e2876", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "ed808f4212ca89d9e43a4bfce042fba8ea53b6fe18660cab7affe4f0ad8e2876", kill_on_drop: false }`
[INFO] [stdout] ed808f4212ca89d9e43a4bfce042fba8ea53b6fe18660cab7affe4f0ad8e2876
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-5-tc1/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-5-tc1/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" "RUSTDOCFLAGS=--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@sha256:2788e3201cd34a07e3172128adcd8b3090168a8e3bcc40d7c032b9dda1df7d1c" "/opt/rustwide/cargo-home/bin/cargo" "+1.76.0" "build" "--frozen" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] 02b479f89bf1935a020194502e36d4c60a9840bad94ee9d64ef65df7747664c7
[INFO] running `Command { std: "docker" "start" "-a" "02b479f89bf1935a020194502e36d4c60a9840bad94ee9d64ef65df7747664c7", kill_on_drop: false }`
[INFO] [stderr]    Compiling mkfs-filesystem v0.1.0
[INFO] [stderr]    Compiling mkfs-ext2 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:2:12
[INFO] [stdout]   |
[INFO] [stdout] 2 | #![feature(error_in_core)]
[INFO] [stdout]   |            ^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error: aborting due to 1 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 `mkfs-ext2` (lib) due to 2 previous errors
[INFO] running `Command { std: "docker" "inspect" "02b479f89bf1935a020194502e36d4c60a9840bad94ee9d64ef65df7747664c7", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "02b479f89bf1935a020194502e36d4c60a9840bad94ee9d64ef65df7747664c7", kill_on_drop: false }`
[INFO] [stdout] 02b479f89bf1935a020194502e36d4c60a9840bad94ee9d64ef65df7747664c7
