[INFO] fetching crate megatiny_hal 0.2.0...
[INFO] testing megatiny_hal-0.2.0 against 1.90.0 for beta-1.91-3
[INFO] extracting crate megatiny_hal 0.2.0 into /workspace/builds/worker-1-tc1/source
[INFO] started tweaking crates.io crate megatiny_hal 0.2.0
[INFO] finished tweaking crates.io crate megatiny_hal 0.2.0
[INFO] tweaked toml for crates.io crate megatiny_hal 0.2.0 written to /workspace/builds/worker-1-tc1/source/Cargo.toml
[INFO] validating manifest of crates.io crate megatiny_hal 0.2.0 on toolchain 1.90.0
[INFO] running `Command { std: CARGO_HOME="/workspace/cargo-home" RUSTUP_HOME="/workspace/rustup-home" "/workspace/cargo-home/bin/cargo" "+1.90.0" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }`
[INFO] running `Command { std: CARGO_HOME="/workspace/cargo-home" RUSTUP_HOME="/workspace/rustup-home" "/workspace/cargo-home/bin/cargo" "+1.90.0" "generate-lockfile" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] [stderr]     Updating crates.io index
[INFO] [stderr]      Locking 6 packages to latest compatible versions
[INFO] [stderr]       Adding bare-metal v0.2.5 (available: v1.0.0)
[INFO] [stderr]       Adding panic-halt v0.2.0 (available: v1.0.0)
[INFO] running `Command { std: CARGO_HOME="/workspace/cargo-home" RUSTUP_HOME="/workspace/rustup-home" "/workspace/cargo-home/bin/cargo" "+1.90.0" "fetch" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] [stderr]  Downloading crates ...
[INFO] [stderr]   Downloaded panic-halt v0.2.0
[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:e90291280db7d1fac5b66fc6dad9f9662629e7365a55743daf9bdf73ebc4ea79" "/opt/rustwide/cargo-home/bin/cargo" "+1.90.0" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] 441ead04f5d5fdf13bfef1b70fcb4ea6d76453b6f44545c264be2ba9225e98c8
[INFO] running `Command { std: "docker" "start" "-a" "441ead04f5d5fdf13bfef1b70fcb4ea6d76453b6f44545c264be2ba9225e98c8", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "441ead04f5d5fdf13bfef1b70fcb4ea6d76453b6f44545c264be2ba9225e98c8", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "441ead04f5d5fdf13bfef1b70fcb4ea6d76453b6f44545c264be2ba9225e98c8", kill_on_drop: false }`
[INFO] [stdout] 441ead04f5d5fdf13bfef1b70fcb4ea6d76453b6f44545c264be2ba9225e98c8
[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:e90291280db7d1fac5b66fc6dad9f9662629e7365a55743daf9bdf73ebc4ea79" "/opt/rustwide/cargo-home/bin/cargo" "+1.90.0" "build" "--frozen" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] 3cbc5986eb0d08b90ff67306108505e7dfce96f379f8cc1161a36e0d0793dff1
[INFO] running `Command { std: "docker" "start" "-a" "3cbc5986eb0d08b90ff67306108505e7dfce96f379f8cc1161a36e0d0793dff1", kill_on_drop: false }`
[INFO] [stderr]    Compiling semver-parser v0.7.0
[INFO] [stderr]    Compiling vcell v0.1.3
[INFO] [stderr]    Compiling panic-halt v0.2.0
[INFO] [stderr]    Compiling semver v0.9.0
[INFO] [stderr]    Compiling rustc_version v0.2.3
[INFO] [stderr]    Compiling bare-metal v0.2.5
[INFO] [stderr]    Compiling megatiny_hal v0.2.0 (/opt/rustwide/workdir)
[INFO] [stdout] error[E0554]: `#![feature]` may not be used on the stable release channel
[INFO] [stdout]  --> src/lib.rs:8:1
[INFO] [stdout]   |
[INFO] [stdout] 8 | #![feature(lang_items)]
[INFO] [stdout]   | ^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: the feature `lang_items` is internal to the compiler or standard library
[INFO] [stdout]  --> src/lib.rs:8:12
[INFO] [stdout]   |
[INFO] [stdout] 8 | #![feature(lang_items)]
[INFO] [stdout]   |            ^^^^^^^^^^
[INFO] [stdout]   |
[INFO] [stdout]   = note: using it is strongly discouraged
[INFO] [stdout]   = note: `#[warn(internal_features)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: lint `const_err` has been removed: converted into hard error, see issue #71800 <https://github.com/rust-lang/rust/issues/71800> for more information
[INFO] [stdout]  --> src/attiny412pac/mod.rs:3:9
[INFO] [stdout]   |
[INFO] [stdout] 3 | #![deny(const_err)]
[INFO] [stdout]   |         ^^^^^^^^^
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(renamed_and_removed_lints)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: lint `private_in_public` has been removed: replaced with another group of lints, see RFC <https://rust-lang.github.io/rfcs/2145-type-privacy.html> for more information
[INFO] [stdout]   --> src/attiny412pac/mod.rs:12:9
[INFO] [stdout]    |
[INFO] [stdout] 12 | #![deny(private_in_public)]
[INFO] [stdout]    |         ^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] For more information about this error, try `rustc --explain E0554`.
[INFO] [stdout] 
[INFO] [stderr] error: could not compile `megatiny_hal` (lib) due to 1 previous error; 3 warnings emitted
[INFO] running `Command { std: "docker" "inspect" "3cbc5986eb0d08b90ff67306108505e7dfce96f379f8cc1161a36e0d0793dff1", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "3cbc5986eb0d08b90ff67306108505e7dfce96f379f8cc1161a36e0d0793dff1", kill_on_drop: false }`
[INFO] [stdout] 3cbc5986eb0d08b90ff67306108505e7dfce96f379f8cc1161a36e0d0793dff1