[INFO] fetching crate ct-utils 0.0.1...
[INFO] testing ct-utils-0.0.1 against 1.75.0 for beta-1.76-1
[INFO] extracting crate ct-utils 0.0.1 into /workspace/builds/worker-1-tc1/source
[INFO] validating manifest of crates.io crate ct-utils 0.0.1 on toolchain 1.75.0
[INFO] running `Command { std: CARGO_HOME="/workspace/cargo-home" RUSTUP_HOME="/workspace/rustup-home" "/workspace/cargo-home/bin/cargo" "+1.75.0" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }`
[INFO] started tweaking crates.io crate ct-utils 0.0.1
[INFO] finished tweaking crates.io crate ct-utils 0.0.1
[INFO] tweaked toml for crates.io crate ct-utils 0.0.1 written to /workspace/builds/worker-1-tc1/source/Cargo.toml
[INFO] running `Command { std: CARGO_HOME="/workspace/cargo-home" RUSTUP_HOME="/workspace/rustup-home" "/workspace/cargo-home/bin/cargo" "+1.75.0" "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" "+1.75.0" "fetch" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-1-tc1/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-1-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" "+1.75.0" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] 2e2f9b775c8b230241a814f17d7a32fb2de99d100510b0fa7264149cab9666bd
[INFO] running `Command { std: "docker" "start" "-a" "2e2f9b775c8b230241a814f17d7a32fb2de99d100510b0fa7264149cab9666bd", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "2e2f9b775c8b230241a814f17d7a32fb2de99d100510b0fa7264149cab9666bd", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "2e2f9b775c8b230241a814f17d7a32fb2de99d100510b0fa7264149cab9666bd", kill_on_drop: false }`
[INFO] [stdout] 2e2f9b775c8b230241a814f17d7a32fb2de99d100510b0fa7264149cab9666bd
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-1-tc1/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-1-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" "+1.75.0" "build" "--frozen" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] 187729e24cc3e70bd54e59809448776547819f55f9de4b618a3c2e01d2cb30e4
[INFO] running `Command { std: "docker" "start" "-a" "187729e24cc3e70bd54e59809448776547819f55f9de4b618a3c2e01d2cb30e4", kill_on_drop: false }`
[INFO] [stderr]    Compiling ct-utils v0.0.1 (/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(specialization)]
[INFO] [stdout]   | ^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: the feature `specialization` is incomplete and may not be safe to use and/or cause compiler crashes
[INFO] [stdout]  --> src/lib.rs:1:12
[INFO] [stdout]   |
[INFO] [stdout] 1 | #![feature(specialization)]
[INFO] [stdout]   |            ^^^^^^^^^^^^^^
[INFO] [stdout]   |
[INFO] [stdout]   = note: see issue #31844 <https://github.com/rust-lang/rust/issues/31844> for more information
[INFO] [stdout]   = help: consider using `min_specialization` instead, which is more stable and complete
[INFO] [stdout]   = note: `#[warn(incomplete_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 `ct-utils` (lib) due to 2 previous errors; 1 warning emitted
[INFO] running `Command { std: "docker" "inspect" "187729e24cc3e70bd54e59809448776547819f55f9de4b618a3c2e01d2cb30e4", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "187729e24cc3e70bd54e59809448776547819f55f9de4b618a3c2e01d2cb30e4", kill_on_drop: false }`
[INFO] [stdout] 187729e24cc3e70bd54e59809448776547819f55f9de4b618a3c2e01d2cb30e4
